Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
transportation planning and public health have important historical connections . in the early 20th century transportation planning and public health
held similar objectives . in 1909 marsh wrote ,  city planning is the adaptation of a city to its proper function .
this conception can be indefinitely expanded but its significance will be appreciated if we admit that no city is more healthy than the highest death rate in any ward or block and that no city is more beautiful than its most unsightly tenement ( p.27 )  . since the early 20th century , the relationship between transportation planning and public health has waxed and waned [ 1 , 3 ] .
there is growing recognition that integration of theories and methods from each discipline is beneficial for advancing research and practice .
of particular relevance to both transportation planning and public health are injuries due to traffic collisions .
worldwide , traffic collisions are one of the leading causes of death among youth and young adults .
a number of intervention strategies including black spot analyses are used in transportation planning to reduce road fatalities .
there is ongoing debate in the transportation planning literature that this type of intervention may have limited effectiveness in reducing road fatalities [ 68 ] .
new approaches are needed to reduce the burden of road traffic fatalities .   given the need to reconnect transportation planning and public health , this paper will present rose 's strategy of preventive medicine [ 9 , 10 ] , a promising intervention approach from public health .
the prevention paradox states that  a preventive measure which brings much benefit to the population offers little to each participating individual ( p.38 )  .
the prevention paradox is based on an important distinction between an individual case and the incidence of cases in a population .
a case is defined as an episode of disorder , illness , or injury affecting an individual , while incidence is defined as
the number of cases of a disease that come into being during a specific time period ( p.44 )  .
the basic principle of geoffrey rose 's strategy of preventive medicine is that the causes of cases ( i.e. , why a specific individual is involved in a collision ) are different from the causes of population incidence ( i.e. , why there are over 3 million collisions per year in the united states ) .
building from the prevention paradox , the primary concept of rose 's strategy is that the majority of cases do not occur in individuals at high risk .
thus ,  a large number of people exposed to a small risk may generate many more cases than a small number exposed to a high risk ( p.59 )  .
the recent study by beck   provides an example of this principle related to road traffic fatalities .
show that pedestrians ( 13.7 deaths per 100,000 person trips ) , cyclists ( 21.0 deaths per 100,000 person trips ) , and motorcyclists ( 536.6 deaths per 100,000 person trips ) are at higher risk of a fatal collision than motor vehicle users . despite their higher risk ,
pedestrians , cyclists , and motorcyclists represent only 20.5% of those killed in traffic collisions .
figure 1 shows that in the usa the majority of trips ( 86% ) and therefore exposure to causes of collisions are greater for motor vehicle users .
thus , the majority of those killed ( 76.6% ) are motor vehicle users who are , on average , at a lower risk ( 9.2 deaths per 100,000 person trips ) than other road users except public transit users .
for interventions to be effective in reducing the total number of road deaths and injury , they must target fundamental causes   ( i.e. , causes of incidence ) , which would result in a global reduction in exposure to a fundamental cause for the entire population . according to the strategy of preventive medicine road traffic fatalities can be neither understood nor properly controlled if high - risk road users are thought to constitute the entire problem .
policies and practices that attempt to prevent traffic fatalities must consider all modes of transportation because they all contribute to the total number of deaths ( figure 1 ) [ 14 , 15 ] . in transportation research , the volume and speed of motor vehicle traffic could be considered two of the fundamental causes of collisions , for all road users [ 16 , 17 ] . throughout the paper , we consider exposure to moving vehicles as a fundamental cause of road traffic deaths and injuries . in this example
, a global reduction in the amount of kilometers driven would result in a reduction of the likelihood of collisions for all road users , a left shift in the risk of road death and injury ( figure 2 ) [ 18 , 19 ] .
for all road users , including pedestrians and cyclists , a reduction in traffic volume contributes to a lower risk of injury and death .
significant public health benefits could be achieved through macrolevel interventions that influence the level of exposure to traffic volumes for all road users , for example , land use and transportation policies that encourage using safer transportation modes ( e.g. , public transit ) and area - wide traffic calming schemes covering whole metropolitan areas , among others . in the usa ,
recent reductions of traffic volume were associated with a reduction in the total number of road fatalities .
rose 's perspective is one way to critically appraise the challenge of reducing the overall burden of collisions while maintaining the benefits of effective mobility .
the implementation of interventions supported by rose 's strategy requires a dialogue between researchers , planners , policy makers , and the public . throughout this discussion
we must recall that the primary function of roadways is not to cause collisions but rather the mobility and productivity of the population . because roadways have multiple functions , policy makers , planners , health officials , and the public
may disagree on how to balance road safety with other competing functions . as rose states ,
 if a problem is common and has been around for a long time , then people come to accept it even if it is large : it is the exceptional or new which causes alarm .
the toll of deaths from road traffic accidents vastly exceeds that from crashing aero planes , but only the latter lead to public health inquiries ( p.57 )  .
as the previous quote suggests , researchers must critically appraise their work and dialogue with policy makers and the public about complex transportation challenges in order to achieve an acceptable balance between the need for mobility and its consequences [ 2224 ] .
ideally , interventions will both improve mobility and reduce the public health burden of road traffic injuries .
in particular researchers must be conscious of the potential influence of structural global economic forces lead by major car and oil companies in influencing road collisions research and discourse [ 21 , 2527 ] .
beck et al . state ,  our findings suggest that a shift from passenger vehicle travel ( lower risk ) to nonmotorized travel ( higher risk ) could result in an overall increase in the numbers of people killed in traffic
measures that prevent crashes and injuries for pedestrians and bicyclists are needed , especially given the recent focus on increasing physical activity through active travel ( p.216 )  .
suggests that the high - risk approach is a more acceptable intervention than a population approach , which would reduce exposure to fundamental causes , volume of motor vehicles in our example , for all road users .
however , in general , interventions targeting high - risk groups ( e.g. , walkers and cyclists ) have limited population wide benefit for injury prevention . targeting the causes of incidence to reduce exposure to motor vehicle volume for all road users , the population approach ,
has the potential for a greater reduction in the total number of transportation fatalities in a population than the high - risk approach .
compares a population approach and a high - risk approach targeting pedestrians and cyclists . in the usa , between 1999 and 2003 , a 25% reduction in the number of pedestrian and cyclist fatalities would have resulted in 1386 fewer deaths ( 1212 for pedestrians , 174 for cyclists ) . a greater number of lives would have been saved by a 4% reduction in the fatal risk for all road users ( table 1 ) .
table 1 estimates the hypothesized effect of decreasing fatal risk over the entire population of road users .
it shows that a 10% and 15% reduction in the fatality risk for all road users would result in a reduction of 4213 and 6320 cases , respectively .
these scenarios would benefit motor vehicle occupants but also pedestrians and cyclists . in urban settings ,
a risk reduction of 15% could be achieved through area - wide traffic calming interventions .   reducing the risk of road death and injury by intervening to reduce the level of exposure to traffic volumes , or other fundamental causes ,
first , the potential reduction in road injuries and deaths is much larger than with high - risk approaches .
second , a population - wide prevention strategy is of benefit to high - risk road users , whatever the criteria used to define  high risk  ( e.g. , transportation mode , alcohol consumption , age group ) .
third , it may also reduce other externalities including pollution , noise , physical inactivity of fundamental causes such as traffic volume [ 21 , 29 ] .   for decades ,
the strong relationship between traffic volume and road traffic injuries or death has been reported , at the street , city , region , or country levels [ 30 , 31 ] .
for all intersections from a road network , safety performance functions show that the expected number of collisions at intersections increases as traffic volume increases , though this relationship is not linear ( figure 3 ) .
the traditional intervention strategy , recommended by the us department of transportation   is to return deviant intersections to within an acceptable range of the average collisions rate at comparable intersections . as seen in figure 3(a ) , this targeted intervention approach aims to move the deviant intersections closer to the best fit regression line .
this is an example of a high - risk approach that does not address the entire population of intersections or injured individuals . in montreal , for example , only 4% of pedestrian injuries occurred at 22 identified black spot intersections , whereas the remaining 96% of pedestrians were injured at more than 3500 different crash sites , none of which were  black spots  .
the population strategy acknowledges that interventions should address the fundamental causes of road deaths and injuries , in our example , the level of exposure to moving vehicles over the entire population , and for all intersections .
the population approach would ask whether it was possible to globally reduce the exposure to traffic volume ( figure 3(b ) ) and subsequently reduce the risk of death and injury at any given intersection for all road users . as the arrows show in figure 3(b ) , the traffic volume and subsequent risk are reduced at every intersection . in theory , it would result in a greater reduction of the number of injured road users than targeting deviant streets and intersections .
rather we present a promising approach to think about road traffic fatalities . a detailed reading of rose 's work [ 9 , 10 ] will provide more precision and help clarify interested readers understanding .
it should be noted that rose 's ideas are not without considerable debate in public health [ 3335 ] .
for example , modeling studies suggest that rose 's approach is generally more cost effective ; however , in certain cases a high risk approach can have better cost / benefit ratios .
for example , recent studies suggest that when compared with other roads , streets with cycle tracks have a lower risk of injury for cyclists [ 36 , 37 ] .
as well , the potential of rose 's strategy for reducing social inequities in health in general [ 34 , 35 ] and in particular road fatalities for those residing in low income areas is still debated .
a vulnerable population approach may be the most acceptable when attempting to act on social inequities ; however , a recent study has shown that reducing traffic volume at all intersections of a canadian city would be most beneficial in poorer neighborhoods .
transportation planning and public health have important historical roots . to address common challenges , including road traffic fatalities , integration of theories and methods from both disciplines is required .
geoffrey rose 's strategy of preventive medicine made an important theoretical contribution to public health and has applications to transportation .
this paper allowed for both public health and transportation research to critically appraise their practice and engage in informed dialogue with the objective of improving mobility and productivity while simultaneously reducing the public health burden of road deaths and injuries .

Answer:
transportation planning and public health have important historical roots . to address common challenges , including road traffic fatalities , integration of theories and methods from both disciplines is required .
 this paper presents an overview of geoffrey rose 's strategy of preventive medicine applied to road traffic fatalities .
 one of the basic principles of rose 's strategy is that a large number of people exposed to a small risk can generate more cases than a small number exposed to a high risk .
 thus , interventions should address the large number of people exposed to the fundamental causes of diseases .
 exposure to moving vehicles could be considered a fundamental cause of road traffic deaths and injuries .
 a global reduction in the amount of kilometers driven would result in a reduction of the likelihood of collisions for all road users .
 public health and transportation research must critically appraise their practice and engage in informed dialogue with the objective of improving mobility and productivity while simultaneously reducing the public health burden of road deaths and injuries .


Question:
You will be shown the title of a chemistry paper, together with sections excerpted from the body of the paper. The paper sections may include HTML tags like `<p>` and `</p>`; please ignore these. Your task is to write an abstract for the paper. Your response should include the abstract and no other text.

Title:
A local mode picture for H atom reaction with vibrationally excited H2O: a full dimensional state-to-state quantum dynamics investigation

Paper sections:

Molecular vibrations have profound effects on chemical reactivity. Consequently, it has been one of the central topics for chemical reaction dynamics to study how initial vibrational excitation inuences reaction dynamics. Early studies on atomdiatom reactions led to the establishment of the well-known Polanyi rules, which state that vibrational energy is more efficient in promoting a late-barrier reaction than translational energy, whereas the reverse is true for an early barrier reaction. 1 In past decades, substantial efforts have been devoted to understanding the dependence of reactivity on the initial excitation of a reactant mode for reactions involving polyatomic reactants. [2][3][4][5][6][7][8][9] The H + H 2 O / H 2 + OH reaction is the simplest system with different vibrational modes, and therefore has become a prototypical system for such a purpose. Crim, Zare, and co-workers carried out a series of experimental studies on the H + H 2 O/HOD/D 2 O reaction and its isotopically substituted analogies. Strong mode specic reactivity has been observed in the H + H 2 O/D 2 O reactions with H 2 O/D 2 O in overtone or fundamental vibrational excitations, and bond selectivity has also been demonstrated in the H + HOD reaction with a preferential cleavage of the HOD vibrationally excited bond. [10][11][12][13][14][15] Theoretically, besides the quasiclassical trajectory (QCT) studies of Schatz et al., [16][17][18] there have been a number of quantum dynamics studies, [19][20][21][22][23] which are in qualitative agreement with the experimental observations. Recently, Fu et al. calculated the exact coupled-channel (CC) integral cross sections (ICSs) for H 2 O and HOD initially in the rst and second stretching excited states and simultaneous excitations of both bending and stretching modes on the YZCL2 PES, and observed strong mode specic and bond selected reactivity as discovered in the experiments. 24,25 Another important question of mode specicity is how the initial vibrational excitation inuences the product state distribution. The Crim group observed that the reaction of water molecules excited to the |04i À overtone state predominantly produces OH (v ¼ 0), while the reaction from the |13i À state produces mostly OH (v ¼ 1). 12 The Zare group showed that for the D 2 O antisymmetric stretch fundamental states (001) and (011), the OD product is produced with little vibrational excitation In this letter, we report the rst full-dimensional quantum differential cross-sections (DCSs) for the title reaction with initial nonrotating H 2 O in the (000), (100) and (001) vibrational states to investigate the initial vibrational excitation inuences on the product state distribution and DCS. The H + H 2 O 4 H 2 + OH and its isotopically substituted reactions are the prototype for the theoretical study of tetra-atomic reactions, in much the same way that the H + H 2 reaction served as the prototype for triatomics. Because three of the four atoms are hydrogens, the system is an ideal candidate for high quality ab initio calculations of a potential energy surface (PES), as well as for accurate quantum reactive scattering calculations. In the past few years, a number of PESs have been constructed with an increasing level of accuracy, [26][27][28][29][30] making the system the rst four-atom reaction with a quantitatively accurate PES. Through the development of the time-dependent wave-packet (TDWP) method, ve-dimensional (5D) state-to-state DCSs were calculated for the H + H 2 O / H 2 + OH reaction with the nonreactive OH bond length being xed for the initial ground rovibrational state. 31,32 Recently, the full-dimensional state-to-state DCSs were reported for the HD + OH / H 2 O + D and D 2 + OH / HOD + D reactions with unprecedented agreement with experiments, 29,33,34 declaring that theory is now able to compete with experimentation in studying simple four-atom reactions at the state-to-state level on given accurate PESs.

We employed the CXZ PES in our calculations, 30 which is the most accurate and smooth PES available, constructed by the neural network (NN) method [35][36][37] based on 17 000 ab initio points calculated at the UCCSD(T)-F12/AVTZ level of theory. The full-dimensional state-to-state quantum calculation is carried out by using the improved reactant-product-decoupling (RPD) scheme based TDWP method. 38,33 The numerical parameters used in the reactant atom-triatom coordinates are as follows: the interaction region was dened by a rectangular box of [1.0,6.0]a 0 in the r 1 coordinate, and [1.0,6.0]a 0 for the R coordinate. The number of vibrational basis functions used was 40 for the r 1 coordinate. For the R coordinate, we used 40 sine discrete variable representation (DVR) points. The asymptotic region was dened from 6.0 to 12.0 a 0 with 42 sine DVR points for the R coordinate and 8 vibrational basis functions for the r 1 coordinates. The number of vibrational basis functions for the nonreactive OH is 12 for interactions and 7 for asymptotic regions. For the rotational motion, we used j 1max ¼ 28 and j 2max ¼ 50, and up to 9 K blocks to compute state-to-state reaction probabilities for J up to 40 to get converged DCSs. Continuous propagation in the product diatom-diatom coordinates only involves a total number of 120 sine functions for the translational coordinate R 0 in a range of [3.0,15.0]a 0 , 5 vibrational basis functions for the H 2 bond, and 3 vibrational basis functions for the OH bond. We used j 1max ¼ 30 and j 2max ¼ 18, and up to 11 K blocks for J ¼ 40. To minimize the computational cost, the coordinate transformation is carried out at every 8 propagation time steps. Since one OH bond is treated as a nonreactive bond in this work, the reaction probabilities and cross sections should be doubled.

Fig. 1 shows the DCSs for the three initial states, each at four collision energies from the threshold energy, in terms of surface plots for the product translational energy and angle distributions for the reaction. It can be seen at the rst glance that the rst symmetric (100) and antisymmetric (001) stretching excited states have essentially identical DCSs. Just like the ground initial state, the DCSs for these two states are strongly backward peaked at the threshold energy. As the collision energy increases, the angular distribution becomes increasingly broader, and the peak position starts to shi gradually to a smaller angle, consistent with the fact that the title reaction is a direct reaction via an abstraction mechanism. At the same collision energy, the DCS for the ground state is very different Fig. 1 Surface plots for the product translational energy and angle distributions for the three initial states (000), (100) and (001) at several collision energies.

from those for the vibrationally excited state. However, one may note that the DCSs at each column shown in Fig. 1 resemble each other very well, indicating that the angular distributions for these three states are similar at the same total energy (because the excitation energy for (100) and ( 001) states are about 0.454 and 0.466 eV, close to the collision energy difference between the ground and vibrationally excited state shown in the gure).

In order to examine the effect of the stretching excitation on the angular distribution in a quantitative manner, we present the total DCSs for the three states at collision energies of 0.8 eV, 1.0 eV, and 1.2 eV in Fig. 2(a). As seen, the vibrational excitations dramatically enhance the DCSs, but with the enhancement factor decreasing considerably as the collision energy increases. The behavior of angle distributions for the excited states is quite different from the ground state at the same collision energy, and the former are sideways peaked and have obvious forward scattering components at E c ¼ 1.2 eV. Moreover, the DCSs for the (100) state are only slightly larger than those for the (001) state at large scattering angles, indicating that one quantum in the symmetric or antisymmetric stretching excitation of H 2 O has nearly identical effects to DCS. Fig. 2(b) shows the total DCSs for the three states at total energies of 0.8 eV, 1.1 eV, and 1.4 eV, which are measured with respect to the energy of the H 2 O ground rovibrational state. Overall, the angle distributions for (000), ( 100) and (001) vibrational states are quite similar at the same total energy of reaction, although the excited states increase the cross section by at least 10 times relative to that for the ground state. As the total energy increases, the sideways scattering components increase substantially, and gradually become dominant. At E tot ¼ 1.4 eV, the angular distributions for the excited states are slightly broader with peaks at 103 , than that for the ground state with a peak at 113 . Therefore, the energy initially deposited in stretching vibrations is much more efficient than the translational energy at promoting the reaction, but has rather similar effects on product angular distribution as the translational energy.

Fig. 3 shows the product H 2 (v ¼ 1) and OH (v ¼ 1) vibrational state populations for the three initial states as a function of total energy. It should be noted that the population for (000) state in Fig. 3(b) was multiplied by a factor of 5 before plotting. When H 2 O is in the vibrational ground state, both H 2 and OH products are vibrationally very cold in the energy region considered here. There is a small fraction of H 2 (v ¼ 1) produced only for  a collision energy higher than 1.25 eV with a population of 1.1% at 1.5 eV, and almost no OH (v ¼ 1) produced. The initial vibrational excitations increase the branching ratios of H 2 (v ¼ 1) and OH (v ¼ 1) channels at the same total energy. The population of H 2 (v ¼ 1) reaches 7.7% at E tot ¼ 1.65 eV. However, the OH vibration excited populations remain small for the initial (100) and (001) states.

These small populations of OH (v ¼ 1) clearly reveal that H 2 O fundamental stretching excitations produce vibrationally "cold" OH as the ground initial state, in agreement with the experimental observation of Zare and coworkers. 15 In the normal mode picture, the (100) and (001) state correspond, respectively, to the symmetric and antisymmetric vibrational excitations of H 2 O with both OH bonds vibrationally excited. Breaking one OH bond by an incoming H atom will leave another OH bond vibrationally hot. However, in the local mode picture, the (100) and (001) states correspond to |10i AE ¼ 2 À1/2 (|10i AE |01i), i.e. each OH bond is a superposition of the ground and rst excited quantum states. When the incident H comes in, it will react with each quantum state independently without any effect from the non-reacting OH group if the non-reacting OH is a spectator, producing OH in the corresponding quantum state. Because the reactivity of the OH excited state is much higher than the ground state, the incident H atom tends to react with the excited state, producing OH mainly in the corresponding ground state. On the other hand, the H atom also reacts with the ground OH state, producing a small fraction of the OH (v ¼ 1) state. The fraction of OH (v ¼ 1) should be approximately equal to the relative reactivity between the OH (v ¼ 0) and OH (v ¼ 1) states. As can be seen from Fig. 3(b), the fraction of the OH (v ¼ 1) population is very close to the relative reactivity. Therefore, the local mode picture works very well here, and the non-reacting OH bond does act as a spectator.

Fig. 4 shows the fraction of total available energy in the product channel going into the rotation and vibration excitation of H 2 and OH as a function of total energy. For the ground state reaction, less than 25% of the available energy goes into the rotational motion of the products in the energy region considered here, and only a very small fraction appears as vibrational energy. The H 2 rotation excitation carries away an increasingly large portion of the internal energy with the increase of collision energy, while the fraction of energy going into the OH rotation excitation essentially does not change with the collision energy. For the excited states reaction, the product rotational distributions are close to those for (000) at the same total energy, leading to a small difference in the fraction of energy. For the H 2 vibration, the difference is bigger. The fraction obtained from vibrationally excited H 2 O is about a factor of 3.5 larger than that from the ground state H 2 O at E tot ¼ 1.5 eV.

Therefore, our state-to-state quantum dynamics study revealed that the stretching excitation is much more efficient at promoting the reactivity than the translational energy, but has a rather similar effect on the angular distribution as the translational energy. The small populations of OH (v ¼ 1) from ( 100) and (001) initial states can be explained clearly by the local mode picture of H 2 O vibration, and reveals that the non-reacting OH does act as a spectator in the reaction. More theoretical efforts should be put into studying higher levels of vibrational excitation and other X + H 2 O reactions in the future to further deepen our understanding of mode-specic chemistry.

Answer: A local mode picture was postulated some time ago to explain the negligible OD product excitation from H reacting with D 2 O in fundamental asymmetrical excitation: the D 2 O asymmetric stretch state is best thought as a linear combination of local mode stretches with the H atom reacting preferentially with the excited OD bond, but has never been verified. Here we report the first full-dimensional state-to-state study for the title reaction with H 2 O in the ground and the first symmetric and asymmetric stretching excited states. It is found that symmetric and asymmetric stretching excited states, which vibrate in very different ways in the normal mode picture, behave essentially identically in the reaction. More importantly, our calculations revealed that the reaction produces a small fraction of OH in the v ¼ 1 state, with the population close to the relative reactivity between the ground and vibrationally excited states, and therefore it confirms the local mode picture for H 2 O in symmetric or asymmetric stretch states when reacting with an H atom.


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
the aim of vital pulp therapy ( vpt ) is to use biomaterials in order to safeguard as much vitality as possible for the dental pulp with carious exposure . direct pulp capping and pulpotomy , the two main vpt procedures , are less invasive than pulpectomy / root canal therapy ( rct ) .
it is well known that the most common cause of pulp / periapical diseases is the presence of bacteria and their by - products within the involved tooth , and the most common pathway of their entrance is through carious lesions ; when further bacterial recontamination is prevented with a good biological seal , the exposed dental pulp has the capability to heal and construct a new dentinal bridge and periapical tissues have the ability of regeneration .
there is a body of evidence for biocompatibility and sealing ability of mineral trioxide aggregate ( mta ) .
currently , mta is as an alternative gold standard for calcium hydroxide , a traditional gold standard , in the field of vpt .
this biomaterial creates a biological seal via hydroxyapatite crystal formation which is improved the first physical seal . despite the advantages , mta has nonpredictable antimicrobial activity , delayed setting time , poor handling characteristics , as well as high cost . the calcium - enriched mixture
( cem ) cement is a newly introduced endodontic biomaterial with similar clinical applications as mta , but different chemical compositions .
this novel cement has an antibacterial effect comparable to calcium hydroxide and superior to mta and sealing ability similar to mta .
recent researches revealed that the biologic response of the pulpal and periapical tissues to the mta and cem cement were comparable in dogs  teeth .
hydroxyapatite crystal formation was reported over the set cem even in normal saline solution . besides the surface characteristics of the set cem cement , as well as the distribution pattern of calcium , phosphorus , and oxygen ions , is similar to dentine .
last but not least , the clinical use of cem has been approved by the iranian ministry of health and medical education . even after carious pulp exposure of symptomatic permanent molars , the pulp can heal , as it has been shown in several studies using mta and cem cement as pulp - capping biomaterials .
this case report discusses a successful treatment outcome of pulpotomy treatment in a symptomatic mature molar with established irreversible pulpitis associate with condensing apical periodontitis .
diagnostic tests were performed ; the involved tooth responded with mild pain to percussion and severe lingering pain to the cold thermal test .
it was not responded within normal limits to the electric pulp test ( ept ) .
a radiographic examination showed a large carious lesion associated with condensing apical periodontitis [ figure 1a ] .
( a ) preoperative radiograph shows a large carious lesion associated with a condensing apical periodontitis .
( b  d ) six months , 1 year and 2 years follow - up radiographs , respectively ; a complete resolution of condensing apical periodontitis is evident .
note the existence of a dentinal bridge beneath the cem cement ; the remaining pulp canal space does not obliterated following clinical and radiographic diagnostic examination , pulpotomy of the first mandibular molar was decided as the treatment .
the tooth was anesthetized with 2% lidocaine with 1:80,000 epinephrine ( daroupakhsh , tehran , iran ) , isolated with a rubber damn and then caries was excavated ; the exposed coronal pulp tissue was removed with a sterile round diamond bur with water spray .
hemorrhage was controlled with sterile cotton pellets ; a ~2 mm layer of the cem cement ( bioniquedent , tehran , iran ) was placed without any pressure to cover the exposed pulp stump .
the patient was re - examined clinically after 1 and 7 days ; tooth mobility was within the normal physiological range , the percussion test was slight positive to negative , and patients were asymptomatic .
six months , one - year , and 2-years follow - ups revealed no clinical or radiographic pathological findings ( i.e. inflammation , infection , calcification , and resorption ) on the first mandibular molar ; radiographs showed normal periodontium apparatus , an evidence of complete periapical healing [ figure 1b  d ] .
the root canal treatment of teeth with irreversible inflamed pulps is basically a prophylactic treatment , since the radicular vital pulp is frequently free of infection and the rationale is to avoid further infection of the root canal system . improved and more conservative vpt has the potential to reduce the need for more invasive / complicated rct .
however , if this is to be achieved in permanent teeth , there is a need for suitable biomaterials for vpt , particularly pulpotomy . in this report , a case of established irreversible pulpitis associated with condensing apical periodontitis
recall examinations revealed that treatment outcomes were successful in preserving pulpal vitality and complete periapical healing of the tooth .
it has been suggested that the existence of a dentinal bridge may at least be an indicator of vpt success , and there are several studies that point to its clinical importance .
however , researchers reported the presence of tunnel defects in dentinal bridge under calcium hydroxide in vpt.[52122 ] they concluded that tunnel defects can serve as pathways for bacterial leakage . unlike ch , the calcified bridge formed by mta is continuous and has no evidence of tunnel defects . according to histological evidence from animal / human studies in mature permanent teeth , the cem cement , like mta , saves pulp vitality and also induces a hard tissue bridge formation , the both .
dentine bridge induced by the cem cement has been shown to be similar to that induced by mta in terms of thickness , absence of tunnel defects , presence of adjacent odontoblast - like cells , predentine , and dentinal tubules .
an important finding was the complete healing of the condensing apical periodontitis with reconstruction of bone structures to normal appearance surrounding the involved molar .
mild inflammatory processes may at times cause the formation of condensing apical periodontitis , mostly involving the mandibular first molar .
various studies have suggested that the key factor in success of vpt is the sealing ability of the material ; on the other hand , the most important cause of failure is bacterial recontamination .
the cem cement favourably prevents microleakage and has sealing ability comparable to mta and superior to irm .
in addition , the cem cement was an effective antibacterial agent . therefore , when bacterial contamination is removed from the dentin - pulp complex in addition to a creation of tight coronal seal to prevent further bacterial recontamination the inflamed but vital pulp of a permanent molar has a chance to return to a healthy and functional status .
all these are resulted in removing the etiologic factor of periapical lesion and complete periapical healing . because pulp / periapical healing was achieved without any need for further intervention
, it seems that the cem cement has the required and acceptable properties to be used as a pulp protective biomaterial .
the exact biological mechanism by which the cem cement promotes pulp healing is currently unknown .
this characteristic is likely to be the result of several properties such as sealing ability , high alkalinity , antibacterial effect , biocompatibility , i.e. dentinogenesis , cementogenesis , low cytotoxicity , pain relief effect , anti - ierr ( inflammatory external root resorption ) effect , hydroxyapatite formation , and similarity to dentine .
besides , recent interesting studies have established favourable treatment outcomes for the cem cement when used in pulpotomy of human permanent teeth with irreversible pulpitis . in the future , biomaterials can play an important role in regenerative dentistry ; they may completely transform our whole philosophy of endodontic treatment .
endodontics seems to be on the brink of an era when a diseased pulp can be a saved one .
there is a realistic biological argument to perform pulpotomy as a promising alternative endodontic treatment in mature permanent teeth ; the results of this case clearly show that cem cement can be used clinically in the treatment of a mature molar associated with irreversible pulpitis and condensing apical periodontitis .

Answer:
this case report describes a pulpotomy treatment of a permanent mature molar tooth with established irreversible pulpitis and condensing apical periodontitis , using calcium - enriched mixture ( cem ) cement .
 clinical examination revealed that the first right lower molar had a large carious lesion with history of spontaneous / lingering pain ; radiographic examination showed condensing apical periodontitis .
 pulpotomy was opted as the treatment ; cervical pulpotomy was carried out .
 following hemostasis , the radicular pulp stumps were covered with ~2-mm - thick layer of the prepared cem cement ; the tooth was restored with amalgam .
 two - year follow - up showed that the treated tooth had been symptomless , and there were no clinical signs / symptoms of either inflammation or infection .
 radiographically , the periradicular lesion was completely healed with reconstruction of bone structures to normal appearance ; the root canals were not calcified . according to chemical , physical , and biological properties of the cem cement ,
 this novel biomaterial may be suitable for endodontic treatment .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
it was recently suggested that endometriosis may commence as an endometrial disease provoked by the aberrant expression of aromatase in this tissue , as this appears to play a pivotal role in its survival in ectopic locations.4 gene array studies have shown that the expression profiles of endometriosis lesions and the eutopic endometrium are similar , which supports the hypothesis that endometriosis is an endometrial disease.6 it is biologically plausible that the presence of aromatase activity in the endometrium is pivotal for the development of endometriosis by blocking phagocytosis by activated macrophages and may also be responsible for the exacerbation of menstrual symptoms whose onset predates the diagnosis of this pathology.1,4,7 in this hypothesis , endometriosis would be a late consequence of enzymatic changes that occur in the endometrium prior to its establishment outside the uterus , which could explain the lag that is often reported between the onset of symptoms and diagnosis of the disease .
this hypothesis could be tested by examining patients with severe dysmenorrhea or infertility to determine whether laparoscopy reveals endometriosis despite aromatase expression already being positive in the endometrium . in the present study
, aromatase expression was determined in the eutopic endometrium of patients with severe menstrual symptoms and/or infertility who underwent laparoscopy and hysteroscopy as a part of their diagnostic work - up .
a total of 106 patients of reproductive age ( range = 1847 years ) received a laparoscopy and hysteroscopy with endometrial biopsy that was carried out using a 4 mm karman curette attached to a 10 ml syringe to produce a vacuum , which is the standard procedure for the evaluation of menorrhagia , severe dysmenorrhea , or infertility in the day hospital where the current study was carried out .
all patients included in this group had reported at least two of these three symptoms for periods ranging from 2 to 8 years .
the control group consisted of sixteen patients who received a laparoscopy for reasons unrelated to infertility or severe dysmenorrhea and who were found to be endometriosis - free during the examination .
the indications for laparoscopy in this group were either benign non - endometriotic ovarian cysts ( seven patients ) or tubal ligation ( nine patients ) . in these patients ,
an endometrial biopsy was performed at the time of the laparoscopy using a 4 mm karman curette .
the patients enrolled in the study gave written informed consent for immunohistochemical studies to be carried out on the endometrial biopsy specimens obtained as part of their standard medical care .
laparoscopies were performed either during the proliferative phase ( n = 72 ) or in the secretory or menstrual phase ( n = 34 ) , since the timing of the procedure depended on the availability of the surgical theater and the specifics of the institution s waiting list .
the laparoscopy reports and color images were retained in the patients files for further evaluation if necessary . during the laparoscopy procedure ,
the surgical team ascertained the presence of endometriosis and graded the stage of the disease in accordance with the american society of reproductive medicine ( asrm ) classification .
8 using laparoscopic classification criteria , the patients with endometriosis were divided into four groups according to the severity of their lesions , using the asrm classification of minimal ( stage i ) , mild ( stage ii ) , moderate ( stage iii ) , or severe ( stage iv ) .
the severity of menstrual symptoms such as dysmenorrhea , the presence or absence of infertility , and the reason for laparoscopy were recorded in the patients files .
aromatase expression was investigated using the commercially available monoclonal antibody mca2077 clone h4 ( serotech , raleigh , nc ) .
antigen retrieval was performed using tris - edta buffer ( ph 8.0 ; sigma - aldrich , so paulo , brazil ) .
the presence of aromatase expression was rated as positive if there was any detectable staining reaction in the glandular epithelium or negative when no reaction was observed .
placental tissue and an atrophic endometrial sample were used as positive and negative controls , respectively , in all immunostaining reactions for aromatase p450 .
statistical analysis was performed using the one - tailed chi - square test for differences in percentages , using an unnamed online interactive calculation tool for chi - square tests of goodness of fit and independence , which is hosted at http://quantpsy.org .
in the group of patients with severe dysmenorrhea , endometriosis was diagnosed in 90/106 patients . in the remaining 16 cases ,
aromatase expression in the eutopic endometrium was detected by immunohistochemistry mainly in the glandular epithelium ( figure 1 ) .
the staining reaction was positive in 66/92 patients ( 72% ) with endometriosis and symptoms of dysmenorrhea and/or infertility , and there were no significant differences between the phases of the patient s menstrual cycle . in symptomatic patients who were found to have normal pelvic results during the laparoscopy ,
aromatase expression was still positive in the endometrium in 13/14 cases ( 95% ) , though this difference was not statistically significant ( p = 0.09 ) . in the asymptomatic control group without endometriosis , however , aromatase expression was negative in the eutopic endometrium in all cases . in the subset of symptomatic patients with a laparoscopic diagnosis of endometriosis ,
the percentage of endometrial samples positively expressing aromatase in the glandular epithelium showed a trend toward greater positivity as the severity of the disease increased in accordance with the asrm criteria .
aromatase expression was detected in the eutopic endometrium of 28/45 patients with stage i endometriosis ( 62% ) , 11/14 patients with stage ii ( 78% ) , 14/20 patients with stage iii ( 70% ) and 12/13 patients with stage iv endometriosis ( 92% ) .
however , only the difference between stages i and iv of the disease was statistically significant ( p = 0.04 ) ( table 1 ) .
the present study not only showed an association between the presence of aromatase expression in the eutopic endometrium and the severity of endometriosis lesions at laparoscopy but also suggests that this expression was already present in symptomatic patients in whom pelvic endometriosis was not found .
these findings agree with the hypothesis that endometriosis may commence as an endometrial disease resulting from functional changes in the endometrium before the disease establishes outside the uterus .
the presence of similar epigenetic changes in the eutopic endometrium and the endometriotic lesions further corroborates the hypothesis that endometriosis is an endometrial disease.6 the positive correlation between mrna levels in the eutopic endometrium and the severity of endometriosis and adenomyosis also supports this hypothesis .
9 whether endometriosis starts as an endometrial disease before establishing itself elsewhere in the pelvis6,7 can not be proven by the present study , but previous work shows that the onset of symptoms associated with this pathology may commence many years prior to its diagnosis , which support this hypothesis .
1 the occurrence of severe dysmenorrhea for many years prior to a diagnosis of endometriosis may reflect these initial endometrial changes favoring the upregulation of both estradiol and prostaglandin production in this tissue.4,6,7 the occurrence of such symptoms in patients with a normal pelvis at laparoscopy , as shown in the present study , may suggest that these functional changes in the endometrium are not only associated with the onset of endometriosis - related symptoms but that they may occur prior to the diagnosis of any pelvic pathology by laparoscopy .
functional endometrial changes leading to an increase in aromatase expression may therefore predate the development of endometriosis , initially provoking dysmenorrhea and possibly infertility before triggering the development of the disease outside the uterus.4 it still remains to be determined whether this group of symptomatic patients represents a high - risk population for the development of endometriosis . in patients with an established diagnosis of endometriosis , however , endometrial positivity for aromatase tends to increase with the severity of the disease .
this may be due to the greater possibility of spontaneous regression of early stage endometriosis , which may occur because of reduced aromatase activity in the eutopic endometrium .
although aromatase expression in the eutopic endometrium may be pivotal for the onset and progression of endometriosis , it has yet to be clarified how this enzyme affects the development of endometriosis .
the role played by estrogens in inhibiting immune surveillance by activated macrophages has been suggested as one of the likely mechanisms by which aromatase affects the course of endometriosis.4,7,10 this local estrogen production in the endometrial cells shed to the pelvis in retrograde menstruation may favor their survival in these ectopic locations by directly preventing their destruction by activated immune cells through the inhibition of the phagocytosis mechanism.1013 the presence of aromatase in the eutopic endometrium may therefore represent the initial step in the development of endometriosis and could be necessary for the development of lesions outside the uterus.7 the similar genetic alterations found between endometriotic lesions and the respective eutopic endometrium also indicate a common histological origin.7 the current study s finding that aromatase expression is detectable by immunohistochemistry in the endometrium of symptomatic , endometriosis - free patients agrees with the hypothesis that this enzyme initially exacerbates dysmenorrhea or causes infertility prior to facilitating the development of endometriosis elsewhere in the pelvis .
a previous study has shown that aromatase expression in the endometrium reduces implantation rates in patients undergoing in vitro fertilization , however , which may help to explain the lower fertility rate of women with endometriosis.14 the presence of aromatase and other enzymes related to estrogen metabolism in the eutopic endometrium will ultimately create a hyperestrogenic milieu , resulting in increased prostaglandin production , particularly because cox-2 expression is upregulated by estradiol in this tissue.69,12,13 this would explain why the pelvis of a patient with severe dysmenorrhea or infertility may be normal , as was reported in the current study
aromatase expression in the eutopic endometrium may be sufficient to provoke these symptoms by enhancing the production of proinflammatory prostaglandins in this tissue .
however , the possibility that some of these endometriosis - free patients have adenomyosis can not be completely excluded in this study , despite the fact that myometrial findings were normal at transvaginal sonography .
estrogens produced locally in the endometriotic lesions and eutopic endometrium result in the mechanism of decreased immune surveillance and enhanced tolerance found in endometriosis,14 which may explain the inverse relationship between estrogen levels and impaired nk - cell function found as a function of the severity of the disease .
15 local estrogen production would also stimulate the production of vegf , growth factors , and inflammatory cytokines by immune cells , thus favoring the progression of endometriosis.12,15,16 the blockade of phagocytosis by the local production of estrogens and the concomitant stimulation of growth and inflammatory factors would explain the paradoxical effects of macrophages in endometriosis , which seem to interact with rather than destroy these ectopic endometrial cells , thus enhancing their growth and angiogenesis.12,17 in conclusion , a vicious cycle of enhanced inflammation and local estrogen production mediated by cox-2 and aromatase expression in the eutopic endometrium of endometriosis patients may play a pivotal role not only in determining the clinical course of this disease but also in defining the intensity of its debilitating symptoms . in the pelvic cavity ,
the ensuing inflammatory reaction provoked by the arrival of endometrial cells will further exacerbate their preexisting aromatase activity , thus augmenting local estrogen production and halting phagocytosis by activated macrophages.6,7

Answer:
objectiveto investigate whether aromatase expression in the eutopic endometrium correlates with the presence and severity of endometriosis in patients with infertility and/or dysmenorrhea undergoing laparoscopy and hysteroscopy.patientsthe study involved 106 patients of reproductive age with symptoms of dysmenorrhea and infertility .
 sixteen endometriosis - free asymptomatic patients were used as a control group.methodsconcomitant laparoscopy and hysteroscopy was carried out in all cases .
 an endometrial biopsy was taken to determine aromatase p450 expression by immunohistochemistry .
 endometriosis was staged according to the american society of reproductive medicine classification.resultsendometriosis was diagnosed by laparoscopy in 92/106 symptomatic patients . in this group ,
 aromatase expression was detected in the eutopic endometrium of 66/92 patients with endometriosis ( 72% ) and in 13/14 ( 95% ) patients in the symptomatic , endometriosis - free group ( p = 0.09 ) .
 aromatase expression was not detected in any patients from the control group . in the endometriosis group ,
 aromatase expression was detected in the eutopic endometrium of 28/45 patients ( 62% ) with american society of reproductive medicine classification stage 1 of the disease , in 11/14 patients ( 78% ) with stage ii , 14/20 patients ( 70% ) with stage iii , and in 12/13 patients ( 92% ) with stage iv ; however , the difference was only statistically significant between stages i and iv ( p = 0.04).conclusionaromatase expression in the endometrium was associated with the presence of dysmenorrhea and infertility irrespective of the presence of endometriosis .
 when endometriosis was present , however , there was a tendency for aromatase expression to be positively correlated with dysmenorrhea severity .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
classic bladder exstrophy ( be ) is a rare malformation of the genito - urinary tract affecting 1:50,000 - 1:100,000 live births .
the surgical reconstruction of the be - epispadias complex has evolved significantly during the last 50 years but is still challenging for the most experienced pediatric urologists , surgeons , and orthopedists .
the upper tracts are almost always normal in the neonates with classic be before abdominal wall , posterior urethral , and bladder closure . the upper tract changes or deterioration of renal function almost always occurs after reconstructive surgery .
the objectives of treatment are to achieve a secure closure of the bladder , pelvis , and the abdominal wall ; preservation of renal function ; urinary continence and creation of functional and cosmetically appealing genitalia .
grady and mitchell have described complete repair of classic be with the combination of bladder closure and epispadias repair at birth . however , the modern staged repair of exstrophy is still considered the gold standard .
this involves bladder closure shortly after birth , followed by epispadias repair at 6 - 12 months of age and bladder neck reconstruction at 4 - 5 years of age . to assess the success of staged reconstruction of the be and its effect on the upper urinary tract , we have analyzed the renal function and continence in 30
between 1994 and 2013 , 30 patients with be have been managed at our institute in various stages of repair , 7 were females and 23 were male patients .
of 30 patients 27 patients underwent primary repair and 3 patients were referred for secondary be closure .
twenty - one children presented before 1 year of age ; four neonates presented before 72 h of birth , in whom bladder closure was done without osteotomy with hip spica only .
three of these patients , who were operated without osteotomy , had bladder dehiscence , hence have undergone secondary repair with bilateral anterior iliac osteotomy and immobilization with external fixators ( efs ) .
eight patients presented before 3 months of age ; all underwent primary bladder closure with bilateral anterior iliac osteotomy and immobilization with hip spica .
nine patients presented between 4 months and 1 year of age , all were operated with primary or secondary exstrophy repair with bilateral anterior iliac osteotomy and immobilization with efs .
two of these children referred with bladder dehiscence , had primary repair with posterior iliac osteotomy ; hence , secondary exstrophy repair was carried out with bilateral anterior iliac osteotomy .
eight children presented between 1 and 5 years of age and one child presented at 9 years of age ; all underwent bladder closure with bilateral anterior iliac osteotomy and immobilization with efs .
the mean and median age of exstrophy repair was 1.25 years and 4 months , respectively .
one patient had failure and six had penopubic or urethro - cutaneous ( uc ) fistulae .
the average age at the time of epispadias repair was 5 years ( 212 years ) .
the triangular flaps of the bladder were incorporated into the bladder instead of de - epithelializing , and using these to buttress the bladder neck repair .
thirteen children have undergone guy leadbetter bladder neck reconstruction , eleven males and two females .
eight children are continent for more than 2 h with good nocturnal continence ; one female child needs clean intermittent self - catheterization ( cisc ) every 34 h for bladder emptying .
two other children also have undergone augmentation cystoplasty and are on cisc every 34 h. one male child , who underwent exstrophy reconstruction at 9 years of age , has surprisingly developed continence after epispadias repair only .
interestingly , one female child who presented at 3 years of age with good bladder plate was operated with bilateral cephalo - trigonal ureteric reimplantation , trigonal tubularization , and bladder and abdominal wall closure with bilateral anterior iliac osteotomy is continent for 3 h after single - stage repair only [ figures 1 and 2 ] .
female exstrophy child with good bladder plate micturating cystourethogram showing good bladder capacity the average age at the time of bladder neck repair was 8 years ( 416 years ) and the mean bladder capacity at the time of repair was 100 ml ( 80200 ml ) .
thirty patients have undergone primary or secondary bladder closure , four neonates presenting before 72 h of life were operated without osteotomy , three of these developed dehiscence .
hence , following this all children were operated with bilateral anterior iliac osteotomy either with hip spica in infants <3 months and efs in all children older than 3 months [ table 1 ] .
primary bladder exstrophy repair / secondary bladder exstrophy repair eighteen children have undergone modified cantwell  ransley epispadias repair , one had a failure and was successfully repaired again .
six children had uc fistula postoperatively ; three healed spontaneously and three required repair [ table 2 ] .
cantwell - ransley epispadias repair thirteen patients have undergone all stages of be repair ; nine are continent for more than 2 h , and four children are continent for < 2 h. one child is continent after single - stage repair ; another child has developed continence after epispadias repair only .
one child with failed bladder neck repair and two children whose bladder capacity was < 80 ml have undergone augmentation cystoplasty .
hence , out of 17 patients ; 14 are socially continent with good nocturnal continence .
two children , who had undergone augmentation cystoplasty , have developed chronic renal failure and are on hemodialysis .
these changes resulted from progressive hydronephrosis due to bladder outlet obstruction after bladder closure in one female patient and after urinary diversion in another male child .
five patients developed bladder calculi after be or epispadias repair , and have developed renal scarring .
these patients who developed renal scarring following closure had one or more documented febrile urinary tract infections .
four patients who are coming for regular follow - up have still not developed adequate bladder capacity and are awaiting continence procedure [ table 3 ] .
the modern staged approach to be reconstruction has undergone significant changes since it was first advocated by jeffs and cendron as quoted by gearhart .
however , the goal of upper tract preservation , obtaining urinary continence , and achievement of satisfactory functional and cosmetic external genitalia remains same .
nonetheless , this success is associated with some risk to the upper urinary tract . usually , these complications are seen after failed initial closure , which can be categorized as complete dehiscence , bladder prolapse , and outlet obstruction . in our series ,
three neonates who were operated without osteotomy had bladder dehiscence ; other 27 children who were operated with bilateral anterior iliac osteotomy did not have bladder dehiscence .
the most critical support for osteotomy is that it allows tension free closure , which prevents subsequent dehiscence and organ prolapsed .
studies from europe and north america have shown that patients requiring repeat closure after failed attempt are less likely to have undergone osteotomy at initial closure .
children operated before 3 months of age had primary bladder closure with bilateral anterior iliac osteotomy and immobilization with hip spica .
in indian summers , it is difficult to maintain hygiene and avoid wound infection in hip spica .
bhatnagar incorporates triangular flaps after urethral lengthening in the bladder repair ; we also incorporate these triangular flaps for the bladder repair .
this not only helps in utilizing bladder tissue for enhancing the bladder capacity but also improves the results of surgery with regard to urinary continence .
the patients with outlet obstruction after initial closure are at risk of hydronephrosis , severe reflux , pyelonephritis , and renal scarring .
one female child with outlet obstruction developed renal scarring and is on hemodialysis . in a review by baker et al .
of exstrophy database , 29 boys and 12 girls were found to have posterior urethral obstruction after closure in the neonatal period . in our patients ,
the most common method of presentation was urinary tract infection seen in eight patients ; of these five had bladder calculi due to intersymphyseal stitch erosion into bladder and one presented with urinary retention .
now we prefer to use dexon suture for pubic symphyseal closure rather than prolene suture .
have revealed an acceptable risk of renal deterioration with 14.7% of patients developing renal deterioration over a follow - up of 12.7 years .
these authors suggest that most significant factors in the development of upper tract scarring after bladder closure are one or more febrile urinary tract infections , failure to use prophylactic antibiotics after bladder closure and presence of progressive hydronephrosis . in baker
et al . series , 22% had upper tract deterioration , including two with chronic renal insufficiency . in our series also , three patients ( 10% ) have developed renal deterioration .
the above statistics clearly suggest that in an infant or child with be , a febrile urinary infection should warrant a renal and bladder ultrasound to rule out hydronephrosis , hydroureter , and to assess bladder emptying . since all patients with exstrophy have various degree of reflux , all should receive chemoprophylaxis .
the prophylaxis should be continued until ureteric reimplantation and bladder neck reconstruction performed and reflux cured and appropriate bladder emptying proven on ultrasound .
the development of hydronephrosis after bladder neck repair can be due to ineffectual bladder emptying , a small inelastic bladder that is not capable of handling increasing volume of urine over time or ureteral obstruction secondary to reimplantation .
this can occur any time after repair , hence the importance of constant regular follow - up evaluations . in our series also , one child developed altered renal function due to small inelastic bladder not capable of handling the increasing volume of urine .
although modified staged reconstruction is being performed at many institutes , grady and mitchell have proposed total reconstruction consisting of the bladder and urethral closure with penile disassembly in the newborn period . however , 50% of these patients required ureteric reimplantation after newborn period for febrile urinary tract infections .
baradaran et al . also stipulate that delayed primary repair of exstrophy does not compromise the rate of bladder growth .
however , children born with smaller templates will have overall smaller capacities and are less likely to undergo bladder neck reconstruction .
while bladder prolapse and dehiscence have been recognized as major complications of primary be repair , posterior urethral outlet obstruction after bladder closure puts bladder and upper tracts at risk and markedly decreases the success rate of modern techniques of staged reconstruction .
therefore , whichever treatment modality is chosen for the newborn with be ; modern type of staged reconstruction , bladder , and urethral closure by penile disassembly in the newborn or urinary diversion , follow - up must be careful and into and including adulthood . in our experience ,
the modern staged repair offers a low risk of renal scarring with acceptable continence opportunity with acceptable cosmetic appearance of external genitalia in the males and females .

Answer:
introduction : classic bladder exstrophy ( be ) is a rare malformation of the genito - urinary tract affecting 1:50,000 to 1:100,000 live births . the surgical reconstruction of the be - epispadias complex is challenging for the most experienced pediatric urologists , surgeons , and orthopedists.purpose:to assess the success of staged reconstruction of the be and long - term effects on the upper urinary tract , renal function , and continence.materials and methods : this is retrospective study ; between 1994 and 2013 , 30 patients with be have undergone stage 1 repair at the institute .
 eighteen male patients have been operated for epispadias repair and thirteen patients have undergone guy leadbetter bladder neck reconstruction .
 three patients required augmentation cystoplasty one child is continent after epispadias repair only and one child attained continence after single - stage repair.results:hence , out of 17 patients , 14 are socially continent , four patients require clean intermittent self - catheterization for bladder emptying .
 four patients , who are coming for regular follow - up , are awaiting continence procedure .
 two patients who underwent augmentation cystoplasty are on hemodialysis for renal failure and one child has altered renal function.conclusion:in our experience , the modern staged repair offers a low risk of renal scarring with acceptable continence opportunity with acceptable cosmetic appearance of external genitalia in the males and females .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:

 the distribution of sandflies correlated with the appearance of cases of leishmaniasis in endemic regions , especially in forested areas .
however , with human intervention and the disappearance of their natural habitat , some species appear to have adapted to degraded habitats , contributing to expansion of their spatial distribution and the spread of leishmaniasis [ 13 ] .
the main factors involved in the transmission of tegumentary leishmaniasis are related to deforestation , urbanization , the presence of domestic animals , and the development of agriculture , particularly the cultivation of cocoa , banana , and coffee .
while some species of sandflies have disappeared , others have become more abundant and have adapted to synanthropic environments by changing their behavior [ 510 ] .
in particular , this expansion has replaced traditional crops with crops that are more productive , which has led to changes in sandflies populations related to altered patterns of dispersal and spatial distribution of these species in new areas [ 1014 ] , because these changes may involve a greater risk of transmission [ 3 , 15 ] .
thus , an understanding between habitat variation and sandflies populations is essential , and to examine whether these changes can increase the risk of transmission of leishmania , we studied populations of sandflies in a conserved area and two distinct agroecosystems .
the agroecosystems located in the parroquia cao el tigre , zea municipality , merida , venezuela , were studied .
these regions have an average elevation of 300400 meters above sea level , covering an area of 135  km , which includes 9,595 inhabitants , a tropical rainforest climate , and temperatures that range between 25 and 30c .
the main economic activities of the region are agriculture and cattle . according to methods previously described in the literature ,
indicators associated with ecoepidemiological levels were recorded using a data sheet that identified the environmental and anthropogenic variables related to the presence of sandflies .
these variables included the climatic conditions ( elevation , temperature , and relative humidity ) , the presence of natural or anthropogenic water bodies , dominant vegetation stratum , crops and animals present , and the level of human interference ( e.g. , logging , burning , and use of fertilizer ) .
the aspects observed concern the vegetation and the presence of both dwellings and animal shelters .
three agroecosystems were selected with varying degrees of ecological disturbance : ( 1 ) a conserved area , predominantly forest , characterized by abundant primary vegetation ; ( 2 ) a fragmented area in which primary vegetation was partially replaced by cocoa crops without management ; and ( 3 ) a disturbed area with complete replacement of primary vegetation , resulting from the degradation caused by human activity related to citrus cultivation , specifically oranges ( figure 1 ) .
captures of adult sandflies specimens were performed for 12-month period , from january 2012 to january 2013 at three agrosystems .
the captures were conducted at the peridomicile areas , using one shannon traps , three cdc traps , six sticky traps , and direct suction with an oral grabber .
sampling was conducted after sunset , when sandflies are most active , between 18:30  h and 20:00  h ; with minimum of one capture by months each collection agrosystem .
shannon traps were conducted in peridomicile areas with three collectors , the cdc light traps were placed in proximity of houses ( poultry houses , breeding pigs , tree , etc . ) , and sticky strips ( white paper sheets 21.6  27.9  cm coated with castor oil ) were placed indoors or outdoors in proximity of houses .
the traps were distributed over 1  ha of the agrosystems and arranged in transect with at least 20  m of distance between each trap . to determine the presence of leishmania promastigotes , the digestive system was extracted via the dissection of live females and examined using phase contrast microscopy at 400x magnification .
we then performed rapid identification of fresh sandflies individuals , and body or representative segments were subsequently cleared in nesbitt solution for 24 hours and were prepared and mounted on slides using berlese 's medium to identify females for corroboration of the species by comparative external and internal morphology .
the methods used were based on community structure , proportional abundance , dominance index , and margalef 's index which was used to calculate biodiversity .
an analysis of the different captures among and agrosystems was conducted using a cluster analysis which was performed using pcord.5 software ( license belonging to icae ) .
the comparison for the different agrosystems was conducted using analysis of variance ( anova ) which was performed with a level of significance of 0.005 , tukey 's test . to investigate the possible association between species distribution and ecosystems
a simple correspondence analysis was carried out using the ibm spss statistical software package , which is publicly available for download at http://ibm-spss-statistics.softonic.com .
the ecoepidemiological characteristics and the degree of disturbance of the 3 agroecosystems are summarized in table 1 .
the shannon traps , cdc light traps , sticky traps , and direct suction captured 94.7% , 2.2% , 1.2% , and 0.9% of the sandflies , respectively .
l. gomezi was the most abundant species in the area , present in all environments studied . according to the abundance values of sandfly specimens collected ,
l. gomezi , l. ovallesi , l. walkeri , l. trinidadensis , and l. panamensis were the main species identified in the 3 agroecosystems .
these species were found at different abundance levels , although l. panamensis was only detected in the conserved forest ( table 2 ) .
cluster analysis was performed to assess the segmentation of each capture , and we identified 2 groups of homogeneous captures with 46% similarity .
the anova results showed significant differences between the populations of sandflies identified in each agroecosystem ( one - way anova , f = 551 , df = 16 , p = 0.000 ) . to further evaluate these differences , a post hoc
tukey 's test was performed for paired agroecosystems , specifically between forest and cocoa agroecosystems and cocoa and orange agroecosystems ( table 3 ) .
the highest values of diversity and species richness occurred in the most conserved agroecosystem , the forest ( 2.26 and 14 , resp . ) .
moreover , the values for diversity and species richness decreased with an increasing degree of ecological disturbance , as observed with the cocoa ( 1.80 and 9 ) and orange agroecosystems ( 1.32 and 7 , resp . ) .
the dominance level was 0.34 in the forest and increased with an increasing degree of ecological disturbance , with the highest value corresponding to the orange grove agroecosystem ( 0.64 ) ( figure 3 ) .
the simple correspondence analysis between sandflies species and agroecosystems identified a strong association between l. gomezi and l. atroclavata with disturbed agroecosystems and a strong association between l. ovallesi , l. walkeri , l. shannoni , l. hernandezi , l. panamensis , l. migonei , l. cayenensis , and l. pilosa with conserved agroecosystems ; species such as l. trinidadensis , l. olmeca nociva , and l. spinicrassa showed no association with any agroecosystem (  : 124.7 ; df = 30 ; p = 0.005 ) ( figure 4 ) . in the conserved agroecosystem ,
l. gomezi , l. ovallesi , and l. walkeri demonstrated natural infection with leishmania species , which were identified as the subgenera leishmania and viannia .
human encroachment on forest ecosystems is driven by logging and agricultural conversion , resulting in sharp and rapidly moving gradients between the relatively cool and humid primary forest and the cultured land , which show strong insolation , higher temperature , and lower humidity .
tropical areas are characterized by a great diversity and wide distribution of sandflies fauna [ 19 , 20 ] . in brazil
, it has been reported that the devastation of natural areas , which includes natural habitats for sandflies , increases the adaptability of these species to environments with human intervention , as observed by the increasing number of cases of leishmaniasis in urban environments .
it is likely that habitat degradation and climate change greatly impact the abundance and richness of sandflies .
the results of this study highlight differences in the sandflies population composition and structure across 3 agroecosystems , characterized by the different degrees of ecological disturbance that were surveyed .
few studies on sandflies have focused on this aspect , as most reports have been limited to epidemiological studies and the documentation of naturally infected species .
in addition , other studies have focused on how the population composition changes in different areas , such as the home and peridomestic or wild environments [ 2224 ] , or according to the type of capture method used .
the results are in concert with others who have proposed that changes in habitat may have a marked impact on the sandflies populations [ 510 ] .
the relationship between leishmaniasis and agricultural activity has been recorded and the relationship between coffee cultivation and the transmission of leishmania by sandflies has been recorded in venezuela , colombia , brazil , and mexico [ 11 , 2629 ] .
this could be explained by the suitability of shade - grown coffee plantations for the resting and breeding of sandflies .
moreover , this type of agroecosystem presents high biodiversity and promotes the presence of many vertebrates , which in turn act as reservoirs of leishmania and potential feeding sources for sandflies [ 30 , 31 ] . in this study ,
the effect of human intervention was reflected in the disturbed agroecosystems as an increase in dominance and a decline in diversity and species richness , relative to less ecologically disturbed areas such as the conserved agroecosystem , where dominance is lower and diversity and species richness are greater .
these results are supported by those of previous studies [ 3 , 21 , 32 ] .
most diversity and species richness in the forest , conserved area , could be caused by higher accumulation organic material to accumulate as a result of the decomposition of leaves and vegetation waste lying on the soil favoring larval development .
environments with significantly disturbed wilderness areas cause certain species to adapt to these new spaces , as observed in our study .
moreover , our results show that anthropogenic modification can favor certain species to colonize these disturbed environments , such as was reported for l. longipalpis   and l. flaviscutellata in urban areas of brazil .
few species are able to adapt to high levels of anthropogenic disturbance , consequently , demographic parameters such as mortality and birth rates for each species are affected differently , and ecosystem structure and dynamics are in turn affected ; yet based on the abundance values , our results suggest that l. gomezi was the species with the greatest ability to exploit disturbed environments [ 3 , 35 ] . both l. gomezi and l. ovallesi have been considered as important vectors of leishmania .
the type of agroecosystem affected the abundance of l. gomezi and l. ovallesi which have an important effect on the probability of humans being bitten by one of these two vectors .
l. gomezi has been reported to have a marked preference for biting humans around homes where vegetation is scarce , and this species has also been known to invade the inside of the home [ 36 , 37 ] .
these findings suggest a greater risk of transmission of the disease in these areas . the abundance of l. ovallesi , a species that transmits leishmania braziliensis , has also been confirmed as a vector of leishmania mexicana in venezuela , and in conserved areas such as forests ,
a potential natural habitat and fragmented areas with cocoa plantations confirm the association of this species with woody vegetation [ 3840 ] .
the sympatric relationship between l. ovallesi and l. gomezi is comparable to what was reported in brazil between l. intermedia and l. neivai , where l. ovallesi is the species with a greater dependence on conserved areas than l. gomezi , predominated near the peridomiciles , indicating a process of adaptation , mainly to this environment of less dense vegetation .
l. gomezi and l. ovallesi as predominant species of primary forest , as the deforestation extended , there was a tendency for l. ovallesi to disappear , suggesting that this species is more dependent on the primary forest than l. gomezi .
in the conserved forest agroecosystem , l. gomezi , l. ovallesi , and l. walkeri demonstrated natural infection with leishmania of the subgenera leishmania and viannia , and this seems to indicate that these species may be transmitting the leishmaniasis agent in the forest agroecosystem area .
if these areas have a greater diversity of sandflies species , it would be expected that there would be a greater coexistence of various species of leishmania , given the specificity between the sandflies vector and leishmania .
moreover , the increased abundance of l. gomezi in disturbed agroecosystems indicates that this species has adapted to new environments modified by humans .
the altered environments favor adaptation of l. gomezi ; these results suggest that the transmission pattern may be changing .
this study provides a basis for further in - depth studies to assess how anthropogenic changes can modulate vector composition and distribution and could also help to explain how this might affect the transmission of tegumentary leishmaniasis in merida and potentially disease risks .
these results clearly show that sandflies fauna exhibited changes in species number as well as population structure in degraded environments . as a result
, changes in the determinants of transmission can lead to the development of new outbreaks .

Answer:
the exploitation of new wilderness areas with crops is increasing and traditional crop substitution has been modified by new more productive crops .
 the results show the anthropogenic disturbance effect on the sandflies population and leishmania transmission in endemic areas of venezuela .
 three agroecosystems with variable degrees of ecological disturbance , forest ( conserved ) , cacao ( fragmented ) , and orangery ( disturbed ) , were selected .
 four methods to sandfly capture were used ; the specimens were identified and infected with leishmania .
 diversity , population structure , anova , tukey test , and simple correlation analysis were carried out .
 shannon traps were able to capture 94.7% of the total sandflies , while cdc light traps , sticky traps , and direct suction just captured 2.2% , 1.2% , and 0.9% , respectively .
 the results showed the effect of ecological disturbance degree on the composition of sandflies and population structure , revealing a dominance level increased but decreased on the diversity and richness of sandflies species in the greatest ecological disturbance area in relation to areas with less organic disturbance .
 environments more disturbed cause adaptability of certain species such as lutzomyia gomezi and lutzomyia walkeri .
 these changes on the composition of sandflies population and structure emerging species could cause increasing of leishmaniasis transmission .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
an estimated 207 million cases of human schistosomiasis have been reported worldwide and about 90% of these live in sub - saharan africa , with nigeria having the highest prevalence .
schistosoma infections cause significant morbidity and mortality with peak prevalence and intensity of infection occurring between the ages 10 and 20 years and subsequent decline by age 65 years .
chronic human circulatory system infection by schistosoma haematobium is reported to affect the urinary bladder and is a possible risk factor in the aetiology of cancers of the bladder and the urinary tract system .
s. haematobium infection has been linked with the development of squamous cell carcinoma of the bladder [ 4 , 5 ] .
s. haematobium associated bladder damage has been closely linked to the immune reaction elicited against the parasite egg deposited in the bladder which eventually induces chronic inflammation related granulomatous injury .
schistosomiasis and bladder cancer share common symptoms such as haematuria , dysuria , and pain with micturition .
this may prevent early diagnosis of bladder cancer and the resultant severe bladder damage particularly in people living in s. haematobium endemic areas . in nigeria ,
most studies have focused on the epidemiology of s. haematobium infection [ 3 , 7 , 8 ] particularly in school - age children , with limited information about the morbidity resulting from urinary schistosomiasis in adults .
this study was therefore aimed at determining the prevalence of schistosomiasis and associated bladder pathology in adults living in eggua , yewa , north local government area , ogun state , nigeria .
the study was carried out in eggua , a rural agrarian community , between august 2012 and may 2013 .
it is one of the wards that make up yewa north local government area as previously described .
it consists of settlements at sagbon , imoto , tata , agbon - ojodu , and igan alade .
two major rivers ( yewa and iju ) flowing through the area serve as the main water source , resulting in high water contact by the inhabitants .
these rivers are used for religious , domestic , and entertainment activities which enhance the transmission of schistosomiasis .
participants aged 30 to more than 60 years old from the community were enrolled for the study .
children were excluded from the study in line with the objective of the study to determine the effect of chronic urinary schistosomiasis on adult members of the community .
informed consent was obtained from each participant under a protocol approved by the local government and local health officials .
ethical approval for the study was also obtained from the ogun state ministry of health .
blood ( 5  ml ) and urine specimens were collected from each study participant .
the urine samples were collected between 10:00 and 14:00 hours to ensure maximum egg yield .
the urine samples ( 10  ml ) were processed for microscopic examination and egg count [ 3 , 10 ] .
the eggs were quantified by counting under the microscope and classified as light infection if there were 50 ( 149 ) eggs/10  ml urine and heavy infection if there were > 50 eggs/10  ml urine .
a blind ultrasound examination was carried out on each participant approximately 1  h after drinking potable water ( 0.11.5 litre depending on the age of the participant ) to distend the bladder .
the classification of bladder pathology or damage was based on the definition of the who [ 11 , 12 ] and shiff et al . ; the abnormalities assessed included abnormal bladder shape , bladder wall irregularities , bladder masses , presence of polyps , calcification , and presence of hydronephrosis in the kidneys .
bladder lesions were considered severely abnormal when four of the above conditions or three conditions as well as hydronephrosis were present in a single individual .
lesions were considered moderate if fewer conditions were seen and negative when no specific lesions were observed .
a structured , pretested questionnaire was used to obtain information about participants ' habits regarding smoking and alcohol consumption , which are determinants of bladder cancer .
statistical analysis of data obtained was done using spss version 20.0 ( p < 0.05 ) .
a total of 257 ( 79 males and 178 females ) participants aged 3090 years were screened for s. haematobium infection and associated bladder pathologies .
the overall prevalence of s. haematobium in the sampled population was 25.68% ( 66/257 ) , 21 ( 31.8% ) in males and 45 ( 68.2% ) in females .
the highest prevalence of infection was observed in participants over 60 years old ( table 1 ) . the majority ( 56/66 ) ( 84.8% ) of those positive for s. haematobium had a light intensity of infection with the egg mean intensity of 16.7 eggs/10  ml urine .
the yewa river was the main source of water for most ( 49/62 ) ( 79.0% ) of the participants infected with s. haematobium ( table 4 ) .
bladder pathologies were observed in 33.9% ( 87/257 ) of the sample population and included abnormal bladder wall thickness ( 39/66 ) ( 59% ) , abnormal bladder shape ( 10/66 ) ( 15.2% ) , bladder wall irregularities ( 15.2% ) , bladder masses ( 1.5% ) , and bladder calcification ( 1.5% ) ( table 2 ) .
bladder wall thickness , the most common abnormality , was recorded in 46/79 ( 58.2% ) males and 90/178 ( 50.6% ) females ( table 3 ) . among the participants ,
56 ( 84.8% ) with bladder pathologies also had an existing schistosomiasis infection , 48 ( 87.3% ) of which were light intensity and 8 ( 72.7% ) of which were heavy intensity :  = 267.5 , p = 0.001 ( table 5 ) .
thus , there was an association between urinary tract pathology and the intensity of s. haematobium infection (  = 375.4 , p = 0.001 , table 2 ) . among the participants with light and heavy intensity of s. haematobium infections , bladder wall thickness was the most common bladder structural pathology
identified in 33/56 ( 58.9% ) and 6 ( 60.0% ) participants with light and heavy s. haematobium infections , respectively ( table 5 ) . abnormal bladder shape and bladder wall irregularity
were seen in 8/56 ( 14.3% ) and 2 ( 20% ) participants with light and heavy infections , respectively ( figures 13 ) .
hydronephrosis was present in only one participant with light infection , while calcification was identified in only one participant with heavy infection .
mild bladder pathology was more common than severe bladder pathology in this study and was found in 48 of the participants ( table 5 ) .
there was a higher incidence of bladder pathologies among female participants ( table 3 ) ; bladder mass and hydronephrosis were also seen only in female participants .
there was no significant relationship between cigarette smoking and bladder pathology in the study ( table 6 ) . among participants with bladder pathology , 29 ( 33.3% ) admitted consuming alcohol while 58 ( 66.7% ) said that they had never consumed alcohol ( table 7 ) .
the overall prevalence rate ( 25.98% ) of adults with s. haematobium infection recorded in this study was slightly higher than 20.8% and 20.0% reported in yewa north local government , ogun state , and owan east local government , respectively , in nigeria [ 3 , 13 ] .
most ( 81.3% ) of the participants depended solely on the s. haematobium contaminated river water , which could account for the higher s. haematobium prevalence ; and little or no schistosomiasis control ( drug ) intervention targeted to adults has been recorded in this area .
the higher frequency of light intensity s. haematobium infection observed in this study could be explained by some level of acquired protected immunity by adults in that community due to chronic exposure to schistosomiasis .
.   found that the proportion of egg - positive individuals falls progressively with age and is a feature in populations with lifelong exposure to the parasite .
therefore , chronicity of infections in older people will more likely be difficult to ascertain using egg count method .
the higher frequency of mild bladder pathology observed in this study was also similar to another study   which observed a higher incidence of mild bladder than severe bladder pathology .
this result could be explained by the low number of participants who smoked cigarettes and consumed alcohol ; these conditions may serve as promoting factors either in progression of bladder pathology to cancer or in making the bladder pathology more severe ( table 4 ) .
in addition , this lifestyle could buttress the possibility of s. haematobium being the principal cause of the reported bladder structural pathology in the study population .
the close relationship between the intensity of s. haematobium infection and the presence of bladder abnormalities was similar to previous reports [ 3 , 1416 ] .
the presence of hydronephrosis in participants with light infection is however at variance with the report of nmorsi et al .
although hydrocalycosis ( a condition mostly mistaken for hydronephrosis ) was observed in some patients with heavy infection , indicating the likely contribution of this infection to kidney pathology .
females ( 64.7% ) had more structural bladder pathology compared to males ( 35.3% ) .
this may be due to higher water contact by females and also to the higher number of female study participants than an indication of a female predilection to bladder pathology .
however , since hydronephrosis and bladder mass or bladder calculi were found together in a female participant , female predilection to bladder pathology may not completely be ruled out . the structural changes to the bladder recorded in this study were in consonance with observations in west madagascar   and nigeria [ 3 ,
15 ] where bladder irregularities and bladder wall thickness were identified as the most common pathologies in individuals infected with s. haematobium . in conclusion , there is evidence that s. haematobium infections may be associated with bladder pathology , on ultrasound examination .
individuals with bladder pathologies could have heavy or light intensity of schistosomiasis infection or have no existing infection at all .
however , a long term exposure to schistosomiasis is necessary for the development of bladder cancer
. further research on the determinants and progress of the bladder pathologies seen in this study population is needed .

Answer:
screening for schistosoma haematobium infection and its possible morbidity was carried out in 257 adult participants in eggua community , ogun state , nigeria .
 parasitological assessment for the presence of ova of s. haematobium in urine and abdominopelvic ultrasonographic examination for bladder and secondary kidney pathology were carried out .
 s. haematobium prevalence of 25.68% ( 66/257 ) was recorded among the participants .
 there was a significantly higher prevalence of 69.2% of urinary schistosomiasis in the females than the prevalence of 31.8% in males ( p = 0.902 ) .
 the intensity of infections was mostly light ( 55 ) ( 21.8% ) compared to heavy ( 10 ) ( 3.9% ) with the mean intensity of 16.7 eggs/10  ml urine .
 structural bladder pathology prevalence among participants was 33.9% .
 the bladder and kidney pathologies observed by ultrasound in subjects with s. haematobium infections included abnormal bladder wall thickness ( 59% ) , abnormal bladder shape ( 15.2% ) , bladder wall irregularities ( 15.2% ) , bladder masses ( 1.5% ) , bladder calcification ( 1.5% ) , and hydronephrosis ( 3% ) .
 infection with s. haematobium was associated with bladder pathology .
 higher frequencies of bladder abnormalities were observed more in the participants with light intensity of s. haematobium infection than in those with heavy infection .
 more bladder pathology was also seen in women than in men , although this was not statistically significant . in conclusion , there is evidence that the development of bladder pathology may be associated with s. haematobium infection .