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:
breast cancer screening programmes are now an established part of the health care service of many countries . the continuous evaluation of this practice is based on observational studies , leading to the possibility of confounding and self - selection bias .
to assess the effect of screening , breast cancer mortality in both screened and not screened women has to be compared ; this can be looked upon as the relative risk ( rr , or rate ratio ) of breast cancer mortality .
confounding bias of the rr occurs when the prevalence of a risk factor ( or set of risk factors ) for breast cancer death is imbalanced across the compared groups . to adjust for the confounding effect
, the prevalence of the risk factor(s ) has to become similar in both groups .
usually age is the only risk factor measured when evaluating population - based breast cancer screening programmes , because information on date of birth and date of invitation of women is mostly available .
this term covers both within - stratum confounding , for example too - broad age categories , and confounding due to unmeasured variables .
self - selection bias can be regarded as a special form of residual confounding because participation may induce an imbalance in the risk factors for breast cancer death .
having accounted for age , we clarified the influence of adjustment for residual confounding on the rate ratio of breast cancer death .
we compared the mortality rate in the screened ( ms ) with not screened women ( mns ) .
this results in an  apparent screening  mortality association ( rra ) that is seemingly real , but not necessarily so because of possible residual confounding bias .
specific screening effect rrs , and a  non - specific effect of the potential confounding factor(s ) c , which is reflected in the following formula .

\documentclass[12pt]{minimal }
				 \usepackage{amsmath }
				 \usepackage{wasysym }
				 \usepackage{amsfonts }
				 \usepackage{amssymb }
				 \usepackage{amsbsy }
				 \usepackage{mathrsfs }
				 \usepackage{upgreek }
				 \setlength{\oddsidemargin}{-69pt }
				 \begin{document}$$ \begin{aligned } { \text{rr}}_{\text{a } }    & = { \text{m}}_{\text{s } } /{\text{m}}_{\text{ns } } \\ & = { \text{rr}}_{\text{s } } * { \text{c } } \\ & = { \text{rr}}_{\text{s } } * \left [ { { \text{p } } _ { 1 } { \text{rr}}_{\text{c } } + \left ( { 1-{\text{p } } _ { 1 } } \right ) } \right]\,/\,\left [ { { \text{p } } _ { 2 } { \text{rr}}_{\text{c } } + \left ( { 1-{\text{p } } _ { 2 } } \right ) } \right ] \\
\end{aligned } $ $ \end{document } the quantity c thus represents the effect of the potential confounder(s ) among screened and the not screened women .
the influence of c depends on the relative risk of breast cancer death rrc , the proportion p1 of screened women with the confounder present , and the proportion p2 of not screened women having the confounder .
the formula is based on previous work by cornfield and colleagues , schlesselman   and greenland .
, that the apparent rra is 0.50 , and a risk factor producing a twofold increase in risk of breast cancer death ( rrc ) is present among 20% ( p1 ) of the screened group and 50% ( p2 ) of the not screened group . then , the non - specific part of the apparent screening effect is 0.20 * 2  +  0.80 * 1  =  1.20 among the screened women , and 0.50 * 2  +  0.50 * 1  =  1.50 among the not screened women . the ratio of these non - specific effects is 1.2/1.5  =  0.80 , which is the influence of confounding ( c ) among the screened and not screened groups .
1a heuristic device to address residual confounding in the mortality effect of breast cancer screening .
both arrows on the left indicate the observed breast cancer mortality risk in the screened and not screened group , suggesting rra  =  0.50 .
we assume that a confounder with a twofold relative risk on breast cancer death ( rrc ) , is present among 20% ( p1 ) of the women in the screened group and among 50% ( p2 ) in the not screened group .
the arrow on the right indicates the expected breast cancer mortality risk in the not screened population when the presence of the risk factor in that group is adjusted from 50% to 20% .
2 ) a heuristic device to address residual confounding in the mortality effect of breast cancer screening . both arrows on the left indicate the observed breast cancer mortality risk in the screened and not screened group , suggesting rra  =  0.50 .
we assume that a confounder with a twofold relative risk on breast cancer death ( rrc ) , is present among 20% ( p1 ) of the women in the screened group and among 50% ( p2 ) in the not screened group .
the arrow on the right indicates the expected breast cancer mortality risk in the not screened population when the presence of the risk factor in that group is adjusted from 50% to 20% .
2 ) in the above calculation we used the cohort approach and the risk ratio ( or rate ratio ) as a measure of effect .
however , this same method can be applied when the odds ratio ( or ) is the effect measure .
control design has been increasingly used for the evaluation of screening programmes [ 612 ] . in the case
control evaluation , the odds of having been screened versus not screened in the case group of breast cancer deaths is compared to the same odds in the control group of invited women from whom the cases originate .
as an example , we report on a case  control study conducted within the nijmegen breast cancer screening programme which started in 1975 . after adjustment for age , we found that the breast cancer mortality rate in the screened group was 65% lower than that of the not screened group : or  =  0.35 and 95% confidence interval ( ci )  =  0.190.64 .
dense mammographic breast pattern , for which a high relative risk of 6 has been reported , is a likely candidate for being treated as a confounding factor . despite its strength ,
nevertheless , suppose its prevalence in all screened women is 5% ( p1  =  0.05 ) in contrast to a supposed 20% ( p2  =  0.20 ) prevalence in the not screened women , then , according to the formula , the apparent or of 0.35 would be adjusted to an or of 0.56 ( see also fig .  2 , left upper diagram).fig .
2diagrams of the adjustment for residual confounding in the effectiveness measurement of breast cancer service screening .
mortality or  =  0.35 ; panel b is for or  =  0.50 and panel c for or  =  0.75 . from top to bottom , the figures represent the adjusted ors for confounding factors with rrc  =  6 , 4 , 2 and 1.5 , respectively .
the x - axis displays the proportion ( p2 ) of the not screened population with the confounding factor .
the lines displayed in the figures present the adjusted or for the confounding factor for p2 ranging from 0.0 to 0.6 , and four different points of departure for p1 of the screened population ( upper line at p1  =  0.05 , then p1  =  0.10 , p1  =  0.20 and the lowest line p1  =  0.35 ) .
the y - axis in each figure depicts the expected ors adjusted for residual confounding diagrams of the adjustment for residual confounding in the effectiveness measurement of breast cancer service screening .
panel a shows the baseline situation of an age - adjusted screening  mortality or  =  0.35 ; panel b is for or  =  0.50 and panel c for or  =  0.75 . from top to bottom , the figures represent the adjusted ors for confounding factors with rrc  =  6 , 4 , 2 and 1.5 , respectively .
the x - axis displays the proportion ( p2 ) of the not screened population with the confounding factor .
the lines displayed in the figures present the adjusted or for the confounding factor for p2 ranging from 0.0 to 0.6 , and four different points of departure for p1 of the screened population ( upper line at p1  =  0.05 , then p1  =  0.10 , p1  =  0.20 and the lowest line p1  =  0.35 ) .
the y - axis in each figure depicts the expected ors adjusted for residual confounding other risk factors for breast cancer like obesity , socio - economic status , nulliparity , late age at menopause , early age at menarche , and family history show a 1.5 to fourfold relative risk of breast cancer at most .
we assume that the risk magnitude of the factors applies to the incidence and mortality alike .
panel a shows the baseline situation of an age - adjusted screening  mortality or of 0.35 ; panel b is for or  =  0.50 and panel c for or  =  0.75 .
the expected values of the ors in order of decreasing magnitude are displayed on the y - axis in each figure : after adjustment for dense breast pattern rrc  =  6 ; late age at menopause rrc  =  4 ; nulliparity rrc  =  2 ; and serious overweight rrc  =  1.5 .
the x - axis shows the proportion ( p2 ) of the not screened population with the confounding factor . in each figure , the lines present the or adjusted for the confounding factor with p2 ranging from 0 to 0.6 , and four different situations of the proportion ( p1 ) confounder in the screened group : the upper line is for a p1  =  0.05 , then p1  =  0.10 , p1  =  0.20 and the lowest line for a p1  =  0.35 . in practice ,
previous screening programme evaluations have qualitatively discussed the magnitude of residual confounding bias on their effectiveness estimate [ 6 , 9 , 10 , 12 ] or estimated the amount of bias due to self - selection [ 7 , 8 , 11 ] .
we present an educated and pragmatic method to quantify the potential impact of residual confounding , and to de - bias the comparison of screened with unscreened groups , a method originally introduced by cornfield et al . .
our results demonstrate that residual confounding has a minor influence on the observed screening effect . closely related to residual confounding
the difference between these three biases is subtle ; the nuances seem to lie in the clarification of definable confounding factors or a combination of indefinable confounding factors .
self - selection into screening may result in an imbalance of a combination of indefinable risk factors , causing a different background risk of dying from breast cancer in screened versus not screened women .
healthy screenee bias may occur because some women in the not screened group , although invited for screening , may already have been diagnosed with cancer , while screened women were not diagnosed with breast cancer at the time of participation .
both biases can be regarded as a form of residual confounding   since participation in screening may be correlated with the baseline risk of dying from breast cancer .
an estimate of the amount of self - selection can be obtained by calculating the ratio of the breast cancer deaths among not invited and not screened women .
this calculation is not possible in a steady state situation of population based screening since there is no uninvited group . by using the implementation period of screening
, we   quantified a 0.84 lower background risk in not screened women compared with not yet invited women .
duffy et al .   proposed a factor based on data from the swedish and canadian screening trials , showing a 1.36 higher risk for not screened women . with these factors ,
the difference in background risk between not screened and screened women can be calculated by taking the percentage uptake in a programme into account .
for instance , if we use duffy s factor of 1.36 and if the screening uptake is 80% , which is in accordance with most european programmes , not screened women have a 1.42 higher background risk compared with screened women .
this factor actually represents c in our formula , it is the difference in background risk p1  =  0 and p2  =  1 . in this scenario an apparent or of 0.35 would be adjusted to 0.51 . however , using our factor of 0.84 , not screened women have a 0.80 lower background risk compared with screened women . in our scenario
an apparent or of 0.35 would be adjusted to 0.28 . in cornfield s original paper
apparent effect , then rra  =  c , and rrs  =  1 . in our example
we applied this method to adjust ors for combinations of p2 between 0 and 0.6 , and values of p1  =  0.05 , 0.10 , 0.20 and 0.35 .
these values were chosen based on the expected prevalence of the risk factors in the female population , i.e. 5% for mammographic density , 10% for late age at menopause , 20% for nulliparity , and 35% for serious overweight .
as , we aimed to challenge the age - adjusted screening effect , we developed scenarios where p1 was smaller than p2 .
our calculation does not account for random error or uncertainties about the relation of risk factors and breast cancer .
it is possible to correct for this by using more complex techniques based on a monte carlo and a bayesian approach .
however , the aim of this study was to present a heuristic device to address residual confounding .
in conclusion , in studies on breast cancer screening the mortality reduction ranges from 38 to 70% [ 612 ] .
as we have shown , residual confounding does not have a great effect on these estimates of screening effectiveness .
after having addressed for age , future breast cancer screening programme evaluations can ignore residual confounding .

Answer:
residual confounding , after adjustment for age , is the major criticism of observational studies on breast cancer screening effectiveness .
 we developed realistic scenarios for the prevalence and strength of risk factors on screened and not screened groups , and explored the impact of residual confounding bias .
 our results demonstrate that residual confounding bias is a minor issue in screening programme evaluations .


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:
improving quality of life and quality and management of care of clients with a schizophrenic disorder by the use of a comprehensive internet based disease management ( dm ) platform . presenting factors influencing the implementation of an internet based dm platform for clients with schizophrenia .
two mental health care institutions in the south of the netherlands participate in the implementation of the digital instrument ( the dm platform ) .
the implementation of the dm platform will be followed by a process and an effect evaluation .
measurement instruments : in the effect evaluation , quality of life , number of symptoms of schizophrenia , quality of care , social functioning , self management , and insight in schizophrenia and its treatment will be measured .
process evaluation : semi - structured interviews will be held with different ( formal primary and secondary , and informal ) caregivers , managers and clients of each institute . these interviews will be conducted before the implementation of the platform and one , two and three years later .
in the digital platform the guideline for people with schizophrenia will be implemented and also information for clients and their home caregivers . when the platform is ready clients will be able to communicate digital with their caregivers in the mental health institute and with their home caregivers and gps .
the effect evaluation starts in september 2009 , the process evaluation has started in may 2009 .
we will have the first results in june 2009 ; they will be used to adjust the implementation and the development of the dm platform . in the meantime
we can report about the building of the dm platform and what the expectations from the future users are .
 what are the factors that influence the process of implementation of a digital tool that provides help and care on a distance ?
 in what way does the digital tool ( care from a distance ) stimulate people who need chronically care to be more self - supporting ?  in what way does the digital tool support professionals to be able to stimulate people with schizophrenia to be more self - supporting ?

Answer:
purposeimproving quality of life and quality and management of care of clients with a schizophrenic disorder by the use of a comprehensive internet based disease management ( dm ) platform . presenting factors influencing the implementation of an internet based dm platform for clients with schizophrenia.contextthe project started in december 2008 .
 two mental health care institutions in the south of the netherlands participate in the implementation of the digital instrument ( the dm platform).the implementation of the dm platform will be followed by a process and an effect evaluation.data sourcemeasurement instruments : in the effect evaluation , quality of life , number of symptoms of schizophrenia , quality of care , social functioning , self management , and insight in schizophrenia and its treatment will be measured .
 process evaluation : semi - structured interviews will be held with different ( formal primary and secondary , and informal ) caregivers , managers and clients of each institute . these interviews will be conducted before the implementation of the platform and one , two and three years later.case descriptionin the digital platform the guideline for people with schizophrenia will be implemented and also information for clients and their home caregivers . when the platform is ready clients will be able to communicate digital with their caregivers in the mental health institute and with their home caregivers and gps .
 they also get information and feed - back about their illness and psycho education.(preliminary ) conclusionsthe effect evaluation starts in september 2009 , the process evaluation has started in may 2009
 . we will have the first results in june 2009 ; they will be used to adjust the implementation and the development of the dm platform .
 in the meantime we can report about the building of the dm platform and what the expectations from the future users are.discussion what are the factors that influence the process of implementation of a digital tool that provides help and care on a distance? in what way does the digital tool ( care from a distance ) stimulate people who need chronically care to be more self - supporting? in what way does the digital tool support professionals to be able to stimulate people with schizophrenia to be more self - supporting ?


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:
a 21-year - old man ( height = 180 cm , weight = 95 kg , body mass index = 29.3 kg / m ) presented to the outpatient department with a long history of frequent and severe snoring . on physical exam ,
after a diagnosis of obstructive sleep apnea was made , a bilateral tonsillectomy and uvulopalatopharyngoplasty was planned for treatment .
prior to surgery , the patient had normal laboratory results with hemoglobin ( hb ) of 15.8 g / dl and no systemic or hematological diseases or history of bleeding disorders . on the day of the surgery , the patient received no premedication due to the history of sleep apnea .
intraoperative monitors included electrocardiogram , non - invasive blood pressure ( bp ) , pulse oximetry ( spo2 ) , and end - tidal co2 .
pre - anesthetic vital signs were bp 120/82 mmhg , hr 68 bpm , and spo2 96% .
general anesthesia was induced with remifentanil 0.5 g / kg / min and propofol 180 mg iv at 10:10 am . at loss of eyelash reflex ,
cisatracurium 16 mg was administered , and the trachea was intubated after a short period of facemask ventilation .
anesthesia was maintained with sevoflurane 2 vol% in 50% oxygen - enriched air and remifentanil 0.2 g / kg / min .
the neuromuscular block was antagonized with glycopyrrolate 0.6 mg and pyridostigmine 15 mg iv without neuromuscular monitoring upon the completion of the surgical procedure at 11:25 am .
postoperatively , a physical examination confirmed the presence of acute bleeding in the left inferior pole of the tonsillectomy site in the post anesthetic care unit .
the surgeon requested an emergent re - operation under general anesthesia for the control of bleeding .
a rsi for a second round of general anesthesia was performed with propofol 120 mg , midazolam 5 mg , and rocuronium 100 mg at 11:55 am .
the surgeon confirmed active bleeding due to an aberrant arterial blood supply in the left inferior pole of the tonsillectomy site .
after the completion of the surgical procedure , no twitch was shown after train - of - four ( tof ) stimulation ( tof = 0 ) with neuro - stim ( model ns-3cc , houston , tx , usa ) at 12:40 pm . the neuromuscular block was then antagonized with sugammadex 200 mg iv and the rocuronium - induced nmb was completely reversed within 2 min .
the patient was transferred to the recovery room , and there were no specific findings on physical exam .
a post - operative laboratory assessment showed hb of 14.6 g / dl ( table 1 ) .
after 6 h and 20 min , the surgeon again requested emergent anesthesia and re - operation for control of bleeding .
the surgeon attempted to control bleeding at the ambulatory otolaryngology clinic but was unable to do so .
when the patient arrived at the operating room ( or ) , vital signs were within normal limits and hb was found to be 13.2 g / dl .
a third round of general anesthesia was induced with propofol 120 mg and rocuronium 40 mg by the on - call resident at 19:00 pm .
the neuromuscular block was antagonized with sugammadex 200 mg iv and a tof = 0 at 20:00 pm .
the patient was again extubated successfully and transferred to the recovery room with no specific findings ( table 1 ) . after 2 h and 35 min ,
when the patient arrived at the or , vital signs were stable and hb was 11.6 g / dl .
a fourth induction of general anesthesia was performed with propofol 120 mg and rocuronium 40 mg by the same resident at 22:35 pm . during tof stimulation
, 1 twitch was seen , and an additional dose of rocuronium 10 mg was given due to bucking 20 min after the induction of anesthesia . at the end of the procedure ,
the neuromuscular block was antagonized with glycopyrrolate 0.4 mg and pyridostigmine 10 mg iv with a tof = 1 at the end of the surgical procedure at 0:20 am .
extubation was carried out after confirming the recovery of consciousness , regular respiration , and the absence of fade on tof monitoring .
after extubation , the patient vomited a large amount of blood on the operating table ( approximated to be more than 200 ml ) .
however , the patient was alert and aware of his surroundings and had regular respirations ( table 1 ) .
after 20 min , the surgeon requested a re - induction of general anesthesia for additional bleeding control .
an rsi for a fifth round of general anesthesia was performed with propofol 120 mg and rocuronium 100 mg at 0:40 am .
the neuromuscular block was antagonized with glycopyrrolate 0.4 mg and pyridostigmine 10 mg iv with a tof = 1 after the surgical procedure was completed at 1:30 am .
approximately 15 min passed after the nmb was antagonized as above , but no evidence of recovery from the rocuronium - induced nmb was seen .
therefore , we injected a bolus of iv sugammadex 200 mg to reverse the residual nmb .
once again , the nmb was completely reversed within 2 min , and tracheal extubation was performed in the or uneventfully ( table 1 ) .
a decision by surgeon was made to perform angiography of the left external carotid artery with subsequent embolization of the bleeding vessel .
embolization of the left ascending pharyngeal artery was performed with polyvinyl alcohol particle ( 350 m ) and tornado embolization microcoil ( cook , bloomington , usa ) ( 3/2 mm ) ( fig .
the patient 's postoperative course was uneventful , and hb was found to be 10.5 g / dl .
pth occurs in approximately 1 in 20 adults ( 5.1% ) , and more than half of patients who bleed are likely to require a procedure of some type to control their hemorrhage .
aberrant arterial blood supply to the tonsillar region derived from the internal carotid artery or the carotid bulb may be present .
to control bleeding , electrocauterization , packing of the pharynx , or angiographic embolization of the feeding artery may become necessary .
the endovascular embolization due to refractory bleeding after tonsillectomy proved to be a valuable treatment method as an effective alternative to surgical intervention .
it is a safe and permanent treatment option in this potentially life - threatening complication . in a case such as this ,
the aberrant arterial blood supply in the left inferior pole of tonsillectomy site caused continuous bleeding .
the anesthesiologist has experienced difficulties , because an experienced surgeon has embarrassed due to repetitive bleeding . in the first induction of anesthesia
, no problems were encountered with conventional anesthesia , although neuromuscular monitoring was not performed .
the most common anesthetic used for rsi during the management of children with pth is succinylcholine . since the introduction of sugammadex , rsi with rocuronium followed by reversal with sugammadex allowed for earlier establishment of spontaneous ventilation than with succinylcholine , which has many adverse side events . during the second round of anesthesia , rocuronium 100 mg ( 1 mg / kg )
was injected for rsi , followed by reversal with sugammadex 200 mg ( 2 mg / kg ) at deep nmb ( tof = 0 ) . during the operation ,
nmb monitoring was difficult due to problems attaching leads to the arms during the operation .
tof stimulation was applied at the ulnar nerve using conventional instrumental monitoring rather than quantitative monitoring due to convenience .
deep nmb was maintained for bleeding control in an attempt to not disturb the procedure . during nmb reversal
, we found an absence of fade on tof monitoring just 2 min after sugammadex was administered .
re - administration of 0.6 mg / kg rocuronium could then be given after sugammadex at the recommended waiting time of 6 h . during the third anesthesia induction ,
an on - call resident used rocuronium 40 mg for muscle relaxation during intubation followed by reversal with sugammadex 200 mg at deep nmb ( tof = 0 ) .
an absence of fade on tof monitoring was shown 2 min after sugammadex was given . for the fourth round of anesthesia , the same resident used rocuronium 40 mg for intubation 2 h and 35 min after the previous nmb reversal with sugammadex .
however , we believe this decision was made without considering the recent sugammadex use . when rocuronium is used within a short time interval ( less than 6 h ) after sugammadex administration , the onset time of rocuronium may be prolonged and may also have an unpredictable duration of action .
we suspect that the additional dose of rocuronium 10 mg due to bucking may be related to the short time interval between sugammadex and rocuronium administration . in situations such as these ,
the benzylisoquinoline class of medications are recommended instead of re - administering rocuronium within 6 h after sugammadex .
when considering this case , cisatracurium for muscle relaxation and intubation may have been a better choice for the fourth round anesthesia . however , one drawback of cisatracurium is the slower onset time than rocuronium .
reversal of the rocuronium - induced nmb with pyridostigmine at a moderate nmb ( tof = 1 ) was uneventful .
after extubation , the patient vomited more than 200 ml of blood on the operating table ; however , he was alert and showed regular respirations .
postoperative nausea and vomiting ( ponv ) after an operation for pth is common due to blood swallowed during the procedure .
therefore , patient awareness and complete reflexes are important , but aspiration must be avoided and monitored closely during the recovery period . however , ponv increases the risk of primary hemorrhage and unexpected postoperative hospital admissions . in this case
the patient did not aspirate , but did have an increased risk of pth due to ponv .
for the fifth round of anesthesia , rocuronium 100 mg ( 1 mg / kg ) was injected for rsi after a time interval from sugammadex administration of 4 h and 40 min .
it has been reported that re - administration of 1.2 mg / kg rocuronium could have been given after sugammadex 2 mg / kg without a waiting time .
however , neuromuscular monitoring did not show the expected recovery , and the patient had residual paralysis after 15 min .
it has been shown previously that the reversal of nmb with anticholinesterase drugs may not be complete after a large dose of a neuromuscular blocking agent .
sugammadex resolved the residual nmb within 2 min , even after reversal with anticholinesterase agents , and is a safe alternative to reversal of nmb induced by steroidal non - depolarizing agents . in this case , deep rocuronium - induced nmb can be reversed successfully with sugammadex at doses of 2 mg / kg and in as little as 2 min .
re - administration of rocuronium within a short time interval after sugammadex may result in unpredictable effects of the nmb agent .
sugammadex made it possible to perform a rapid , complete reverse when the residual block was maintained by an incomplete reversal of anticholinesterase .

Answer:
post - tonsillectomy hemorrhage ( pth ) is the most frequent complication of tonsillectomy , and occasionally results in a lethal outcome .
 a 21-year - old man ( height 180 cm , weight 95 kg ) was scheduled for a bilateral tonsillectomy and uvulopalatopharyngoplasty for treatment of obstructive sleep apnea .
 he required 5 rounds of general anesthesia due to recurrent pth .
 the anesthesiologist used sugammadex a total of 3 times to achieve the successful reversal of the deep neuromuscular blockade ( nmb ) induced by rocuronium .
 after sugammadex 2 mg / kg was administered , the nmb was reversed in 2 minutes each time .
 re - administration of rocuronium within a short time interval after sugammadex may result in unpredictable effects of neuromuscular blocking agents .
 sugammadex made it possible to perform a rapid , complete reverse when the residual block was maintained by an incomplete reversal of anticholinesterase .


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:
acute cholecystitis is an inflammation of the gallbladder due to obstruction of the neck or cystic duct , primarily caused by gallstones .
acute cholecystitis is characterized as a combination of local and systemic inflammation , and its treatment is dependent on the severity , although it is often treated conservatively with antibiotics .
when acute cholecystitis becomes severe , it is treated surgically , while for some patients , percutaneous transhepatic gallbladder drainage ( ptgbd ) is an alternative to surgery .
an accurate assessment of the severity is critical for the appropriate management of acute cholecystitis .
abdominal ultrasonography ( us ) is useful for the diagnosis of diseases of the abdominal cavity . with abdominal us ,
however , this condition can be treated more appropriately if the severity is evaluated , using diagnostic imaging prior to the occurrence of organ failure or worsening of blood test variables . with regard to diagnostic imaging
, wall thickening is representative of edema and correlates with the severity of acute cholecystitis , while inflammation is indicated by both edema and increased blood flow . if blood flow is assessed using abdominal us , it is possible to more accurately evaluate the severity of acute cholecystitis .
superb microvascular imaging ( smi ) is based on color doppler imaging of abdominal us and enables the visualization of very slow blood flow without requiring contrast medium .
it is composed of color - coded ( csmi ) and monochrome smi ( msmi ) , where csmi visualizes pulsatory signals such as color doppler images and msmi enhances the blood flow signal by suppressing background signaling .
, we present the changes observed using csmi and msmi over the course of an acute cholecystitis in 1 patient .
an 84-year - old man was admitted to the national hospital organization shimoshizu hospital with right upper abdominal pain that persisted for 3 days .
white blood cell count ( wbc ) and c - reactive protein ( crp ) levels were 11.4  10/l and 15.3 mg / dl , respectively .
total bilirubin , alkaline phosphatase , aspartate aminotransferase , alanine aminotransferase , and -glutamyl transpeptidase levels were 1.5 mg / dl , 206 iu / l , 20 iu / l , 10 iu / l , and 10
the possibility of obstructive jaundice was low . to clarify the cause of inflammation , computed tomography ( ct ) scans ( somatom emotion 16 ; siemens , munich , germany ) were performed , which showed slight thickening of the gallbladder wall ( fig .
1a ) . to confirm the results of the ct scans , the patient was subjected to abdominal us ( applio 400 ; toshiba medical , ohtawara , japan ) with a curved array transducer ( pvt-375bt ) at 3.75 mhz ( toshiba medical ) .
the severity was classified as  mild as the patient showed no signs of organ failure .
diagnostic imaging found no evidence of marked local inflammation such as pericholecystic or hepatic abscess .
the patient was treated conservatively with antibiotics ( cefazolin sodium 3 g / day ) intravenously from the date of admission .
after 2 days of treatment , right upper abdominal pain still persisted , and his body temperature rose to 38.7c .
wbc and crp levels rose to 15.6  10/l and 19.6 mg / dl , respectively .
these data indicated that the acute cholecystitis had worsened . to evaluate the acute cholecystitis morphologically ,
abdominal us showed that the wall thickness of the gallbladder had increased and a sonolucent area was visible ( fig .
complications , such as liver abscess or peritonitis , were considered possible . to avoid complications and promote recovery ,
seven days after ptgbd , wbc and crp levels were 6.8  10/l and 1.2 mg / dl , respectively , also confirming recovery .
, csmi showed a pulsatory signal on the wall of the gallbladder with the curved array transducer ( 2.0 cm / s ; pvt-375bt ) at 3.75 mhz ( fig .
2a ) , whereas no such signal was observed on the wall with msmi ( 2.2 cm / s ) ( fig .
when his acute cholecystitis had worsened , this signal became more evident with csmi ( fig .
after ptgbd , the gallbladder shrank due to drainage of the gall and the pulsatory signal was no longer visible with either csmi ( fig .
abdominal us is recommended as a first - line diagnostic imaging tool for the diagnosis of acute cholecystitis ; however , false negatives are a known issue of this technique . in our case , a pulsatory signal was observed on the wall of the gallbladder on the day of admission , which suggested positive csmi , even when wall thickening was minimal .
smi is expected to reduce the incidence of false negatives when diagnosing this condition . in the present case , the strength of the pulsatory signals correlated with the severity of the gallbladder inflammation , as illustrated using both csmi and msmi .
the results suggest that the signal intensity of csmi and msmi is correlated with the severity of inflammation .
our case shows that both csmi and msmi are useful for the diagnosis and evaluation of the severity of acute cholecystitis .
contrast - enhanced abdominal us shows a strong enhancement that successfully differentiates acute cholecystitis from a healthy gallbladder and chronic cholecystitis .
however , unlike contrast - enhanced abdominal us , smi does not require contrast medium and is therefore suitable for the management of acute cholecystitis .
a primary limitation of the present study is that it is based on just 1 case of acute cholecystitis . in order to confirm the usefulness of smi for the evaluation of the severity of acute cholecystitis
, more patients should be enrolled in larger studies and smi findings for acute and chronic cholecystitis compared .
furthermore , signal intensity should be stratified against the severity of acute cholecystitis . in conclusion ,
a strong pulsatory signal correlated with the severity of acute cholecystitis with both csmi and msmi and may be suitable for the evaluation of the severity of this condition .
this report was approved by the ethical committee of the national hospital organization of shimoshizu hospital .
the study was considered an element of daily clinical practice as opposed to a clinical trial .
written informed consent was obtained for the performance of contrast - enhanced ct and ptgbd .
the patient 's records were anonymously and retrospectively analyzed , and written informed consent was obtained for their use in this report .

Answer:
evaluation of the severity of acute cholecystitis is critical for the management of this condition .
 superb microvascular imaging ( smi ) enables the assessment of slow blood flow of small vessels without any contrast medium .
 an 84-year - old man visited our hospital with right upper abdominal pain . computed tomography and abdominal ultrasonography showed a slight thickening of the gallbladder .
 white blood cell count and c - reactive protein levels were elevated .
 he was diagnosed with acute cholecystitis and treated conservatively with antibiotics .
 two days later , his condition worsened and percutaneous transhepatic gallbladder drainage ( ptgbd ) was performed .
 the patient recovered and was discharged , and his drainage was withdrawn 7 days later . on admission ,
 color - coded smi ( csmi ) showed pulsatory signals on the slightly thickened gallbladder wall . on the day of ptgbd
 , the intensity of the signal on csmi had increased .
 once the patient was cured , no further signal was observed on the gallbladder wall with either csmi or msmi . in conclusion , the strong pulsatory signal correlated with the severity of acute cholecystitis observed with csmi and msmi . illustrating the signal intensity is useful for the evaluation of the severity of acute cholecystitis .


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:
genomic dna hypomethylation has been observed in the peripheral blood mononuclear cells of leukemia patients and in tumor cells of patients with b - cell lymphoproliferative diseases ( 1 ) .
dna methylation may affect karyotypic stability , may influence euchromatin - heterochromatin interactions , and has been correlated with disease progression ( 2 ) . on the other hand ,
for example , some patients with lymphomas do not express tumor suppressor genes because the promoters of these genes are methylated .
, bone marrow produces a large number of abnormal white blood cells , which overwhelm the other types of blood cells , including red blood cells and platelets , thus impairing the production of normal white blood cells . in clinical classification , leukemia can be classified as acute myeloid leukemia ( aml ) and chronic myeloid leukemia ( cml ) .
cml is a clonal disease of stem cell origin that is characterized by the presence of the philadelphia chromosome ( ph+ ) , which has been named t(9,22)(q34:q11 ) .
its fusion gene product , bcr - abl , is a constitutively active tyrosine kinase .
nevertheless , the differential factors through which they produce a different type of leukemia are not yet completely understood . in hematopoietic malignancies ,
hypermethylation of several genes including e - cadherin , dap kinase , estrogen receptor ( er ) alpha , and p15 are associated with gene inactivation ( 7 - 10 ) .
genes , such as dab2ip , dlc-1 , h - cadherin , id4 , integrin 4 , runx3 , sfrp1 , and shp1 , has been identified as being implicated in aberrant dna methylation during development of human malignancy ( 11 - 18 ) . in order to gain insight into the differential epigenetic alterations in leukemia , we investigated the methylation statuses at selected locus of these genes in aml and cml patients using a methylation - specific polymerase chain reaction ( msp ) .
diagnostic bone marrow samples were obtained from 23 patients with aml and 21 patients with cml .
the samples were gathered by the division of hematology / oncology ( department of internal medicine , korea university medical center , seoul , republic of korea ) and analyzed by pathologist . institutional review board approval and informed consent were obtained ( kumc - irb-2006011-p-1 , kumcirb-2006012-p-2 ) . of the aml patients , 17 males and 6 females were included , with ages ranging from 26 to 78 yr , at a median age of 45.61 ( sd , 15.56 ) yr . of the cml patients ,
11 males and 10 females were included , with ages ranging from 18 to 75 yr ( meansd , 49.9116.53 ) . as controls ,
22 normal peripheral bloods were obtained from healthy volunteers ( 11 males and 10 females ) ranging from 20 to 78 yr of age ( meansd , 45.3620.64 ) .
chemical modification was performed as described previously , with minor modifications ( 19 ) . in brief
, 1 g of genomic dna was denatured by incubation with 0.2 m naoh for 10 min at 37 , followed by the addition of 550 l of 3 m sodium bisulfite ( ph 5.0 ) ( sigma , st .
louis , mo , u.s.a . ) and 10 mm hydroquinone ( sigma ) , which was brought to a final volume of 600 l .
the mixtures were incubated at 55 for 16 hr , and the modified dna was then desalted with the wizard clean - up system ( promega corp . ,
we performed polymerase chain reaction ( pcr ) using specific pcr primers capable of distinguishing between methylated and unmethylated dna sequences .
the primers for the unmethylated and methylated dna sequences , pcr product size , and annealing temperature are shown in table 1 .
the msp primer sets were selected at the 5'-cpg island regions of genes using the methprimer software ( www.urogene.org ) .
the pcr conditions were as follows : initial denaturation and hot start at 95 for 5 min , and cycles consisting of 30 sec at 95 , 30 sec at the annealing temperature , and 30 sec at 72. in addition , sck , a human cholangiocarcinoma cell line , was used as positive control for integrin 4 gene ( 20 ) .
msp results were analyzed as a dichotomous variable based on the presence or absence of gene methylation .
the msp results of tumor and normal samples were compared and analyzed with the pearson chi - square test ( version 12 ; spss inc . ,
diagnostic bone marrow samples were obtained from 23 patients with aml and 21 patients with cml .
the samples were gathered by the division of hematology / oncology ( department of internal medicine , korea university medical center , seoul , republic of korea ) and analyzed by pathologist . institutional review board approval and informed consent were obtained ( kumc - irb-2006011-p-1 , kumcirb-2006012-p-2 ) . of the aml patients , 17 males and 6 females were included , with ages ranging from 26 to 78 yr , at a median age of 45.61 ( sd , 15.56 ) yr . of the cml patients ,
11 males and 10 females were included , with ages ranging from 18 to 75 yr ( meansd , 49.9116.53 ) . as controls ,
22 normal peripheral bloods were obtained from healthy volunteers ( 11 males and 10 females ) ranging from 20 to 78 yr of age ( meansd , 45.3620.64 ) .
chemical modification was performed as described previously , with minor modifications ( 19 ) . in brief
, 1 g of genomic dna was denatured by incubation with 0.2 m naoh for 10 min at 37 , followed by the addition of 550 l of 3 m sodium bisulfite ( ph 5.0 ) ( sigma , st .
louis , mo , u.s.a . ) and 10 mm hydroquinone ( sigma ) , which was brought to a final volume of 600 l .
the mixtures were incubated at 55 for 16 hr , and the modified dna was then desalted with the wizard clean - up system ( promega corp . ,
we performed polymerase chain reaction ( pcr ) using specific pcr primers capable of distinguishing between methylated and unmethylated dna sequences .
the primers for the unmethylated and methylated dna sequences , pcr product size , and annealing temperature are shown in table 1 .
the msp primer sets were selected at the 5'-cpg island regions of genes using the methprimer software ( www.urogene.org ) .
the pcr conditions were as follows : initial denaturation and hot start at 95 for 5 min , and cycles consisting of 30 sec at 95 , 30 sec at the annealing temperature , and 30 sec at 72. in addition , sck , a human cholangiocarcinoma cell line , was used as positive control for integrin 4 gene ( 20 ) .
msp results were analyzed as a dichotomous variable based on the presence or absence of gene methylation .
the msp results of tumor and normal samples were compared and analyzed with the pearson chi - square test ( version 12 ; spss inc . ,
the multiple genes were found to be methylated in bone marrow from patients with aml or cml . specifically , the frequencies of promoter hypermethylation at selected locus in the 23 aml samples were : 78.3% ( 18/23 ) for shp1 , 65.2% ( 15/23 ) for id4 and sfrp1 , 26.1% ( 6/23 ) for h - cadherin , 8.7% ( 2/23 ) for dlc-1 , and 4.3% ( 1/23 ) for dab2ip and runx3 .
the frequencies of dna hypermethylation at selected locus in the 21 cml samples were : 28.6% ( 6/21 ) for shp1 , 19.0% ( 4/21 ) for h - cadherin , 14.3% ( 3/21 ) for id4 , 9.5% for ( 2/21 ) for sfrp1 , and 0% ( 0/21 ) for dab2ip , dlc-1 , integrin 4 , and runx3 ( fig .
however , promoter hypermethylation of the 22 normal peripheral bloods was observed less frequently ( table 2 ) . there was a statistically significant difference between normal peripheral bloods and aml with respect to the frequencies of methylation of id4 , sfrp1 , and shp1 ( pearson chi - square test ; p<0.0001 , p<0.0001 , and p<0.0001 , respectively ) and between normal peripheral bloods and cml with respect to the frequencies of shp1 methylation ( pearson chi - square test ; p=0.007 )
. furthermore , there was a statistically significant difference between the dna methylation frequencies of aml patients and cml patients .
the frequencies of dna methylation of id4 , sfrp1 , and shp1 were higher in aml compared to those in cml ( p=0.001 , p<0.0001 , and p=0.001 , respectively ) ( table 2 ) .
in contrast , no statistical differences between aml and cml were detected in other genes such as dlc-1 , dab2ip , h - cadherin , integrin 4 , and runx3 .
promoter methylation results at selected locus of eight genes with msp method were shown in fig .
the results of the present study demonstrate the substantially increased frequency of promoter hypermethylation in id4 , sfrp1 , and shp1 genes in aml compared to cml .
leukemia , a heterogeneous group of hematopoietic malignancies that occur worldwide , includes acute and chronic myeloid leukemia . despite many important advances in understanding the different biological and cytogenetic aspects of acute and chronic leukemia ,
it is understood that some kinds of leukemia present specific cytogenetic alterations ( 21 ) .
different types of leukemia usually have specific epigenetic modifications that cause the activation of oncogenes and , in particular , the formation of abnormal fusion genes such as aml1-eto ( 22 , 23 ) , a fusion protein resulting from t(8,21 ) translocation that commonly occurs in aml .
another typical example is the fact that bcr - abl is a constitutively active , cytoplasmic tyrosine kinase that is generated by t(9;22 ) translocation in more than 95% of cml ( 24 ) .
the central role of epigenetic modification of these genes in leukemia development promoted them as reasonable targets for understanding the differential mechanism between acute and chronic leukemia . in the present study , id4 , sfrp1 , and ship1
these results suggest that the epigenetic modification of these genes may play specific roles in the development of aml rather than cml and , thus , promoted them as ideal targets for drug development to treat aml . in the future , it is clearly imperative to understand the patho - physiological differential mechanisms of these genes in aml , and to finally explore novel therapeutic strategies . in present study ,
methylation frequencies of shp1 gene were the high detected in cml as well as aml .
shp1 is a member of the shp family of proteins , cytoplasmic protein tyrosine phosphatase ( ptp ) , and has been known as a candidate tumor suppressor gene in lymphoma , leukemia and other cancers ( 25 ) .
also , the hypermethylation of shp1 gene was frequently detected in several human cancers and the reduced expression of the shp1 gene in various types of leukemias and lymphomas mainly occurred by promoter methylation ( 26 - 28 ) . therefore , these results indicate that aberrant dna methylation of shp1 gene may be related to the tumorigenicity of myeloid leukemia .
the methylation frequencies of the dab2ip , dlc-1 , and runx3 genes were detected at different levels in acute and chronic leukemia patients ; however , the difference was negligible . in some genes like integrin 4 gene ,
however , hypermethylation of these genes was frequent event in esophageal squamous cell carcinomas , lung cancers , and gastric cancers ( 11 , 12 , 15 , 16 ) .
thus , dna methylation of these genes may be not related to tumorigenicity of aml / cml in contrast with other cancers . in summary , we have identified that aberrant dna methylation of shp1 is a frequent event in aml and cml . also , the frequencies of dna methylation of several methylation - controlled genes , including id4 , sfrp1 , and shp1 , were higher in aml patients compared to those in cml patients .
although these results should be confirmed , more comprehensive studies are necessary involving various known risk factors such as smoking and occupational carcinogens , and genetic susceptibilities .
our results suggest that aberrant dna methylation of shp1 may be related to the tumorigenicity of aml and cml and hypermethylation of id4 , sfrp1 , and shp1 genes may contribute to the pathogenesis mechanism of aml specifically .

Answer:
to gain insight into the differential mechanism of gene promoter hypermethylation in acute and chronic leukemia , we identified the methylation status on one part of 5'cpg rich region of 8 genes , dab2ip , dlc-1 , h - cadherin , id4 , integrin 4 , runx3 , sfrp1 , and shp1 in bone marrows from acute myeloid leukemia ( aml ) and chronic myeloid leukemia ( cml ) patients . also , we compared the methylation status of genes in aml and cml using methylation - specific pcr ( msp ) .
 the frequencies of dna methylation of id4 , sfrp1 , and shp1 were higher in aml patients compared to those in cml patients . in contrast , no statistical difference between aml and cml was detected for other genes such as dlc-1 , dab2ip , h - cadherin , integrin 4 , and runx3 .
 taken together , these results suggest that these methylation - controlled genes may have different roles in aml and cml , and thus , may act as a biological marker of aml .


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:
hardware removal is indicated for infection , nonunion , failure of fixation , pain , soft tissue irritation , and anticipated strenuous activity after fracture healing [ 14 ] . during removal cases
subsequent removal of broken hardware increases surgical time , and retained metalwork potentially complicates future surgeries ( figure 1 ) .
although there have been several articles that have discussed titanium implant failure , most have discussed this issue within the context of hardware failure during fracture healing , and not particularly during removal of hardware [ 69 ] . to our knowledge
, none have been specific to the elbow , which merits its own discussion due to its unique anatomy .
the distal humerus of the elbow is unique in that is has a high ratio of cortical to cancellous bone .
therefore , in this study we set out to investigate incidence of bone screw failure during hardware removal procedures and we were interested in comparing titanium and stainless steel bone screws because these are the most common types of metallic fracture implants in circulation .
in addition , we set out to determine whether the duration of implantation and the anatomic location of the bone screws about the elbow were associated with bone screw failure during removal procedures
. a better understanding of metallic hardware failure during removal procedures may help surgeons in the preoperative planning stages of these cases , in terms of surgical tool selection and staff availability .
after institutional review board ( irb ) approval , all cases performed by orthopaedic trauma or upper extremity surgeons between 1/1/2000 and 10/1/2009 at our level 1 trauma center were reviewed .
inclusion criteria were ( 1 ) deep implant removal cases , ( 2 ) hardware removed from the distal humerus or the proximal ulna , and ( 3 ) isolated elbow injuries .
the exclusion criteria were ( 1 ) cases that did not have relevant or inaccessible elbow x - rays , ( 2 ) single screw fragment extraction cases ( because in these cases the hardware had previously broke and was small in size , which we believe was not representative of the other screws being removed ) , ( 3 ) patients younger than 17 years , and ( 4 ) cases that were originally performed at an outside institution ( unavailable medical records ) . the factors considered were ( 1 ) whether or not the bone screws broke during removal and the type of implant metal used ( titanium alloy , ti6al4v or stainless steel ) , ( 2 ) the length of time between initial implantation and removal , where cases were divided into two groups based on a conservative estimate of the time period required for osseointegration of titanium implants [ 10 , 11 ] : one group was for cases where the duration of time between implantation and removal was less than 12 months and the second group was for cases where the duration between implantation and removal was 12 months or more ; and ( 3 ) anatomic location about the elbow ( distal humerus or proximal ulna ) .
the data was extracted from the medical record . due to the small sample size , fisher 's exact test was used to determine statistical differences between two sets of categorical data .
an independent t - test was used to compare the means of two independent groups .
differences that had less than 0.05 probability of occurring from chance were considered statistically significant .
we identified a total of 47 cases , of which 21 met the inclusion criteria .
we carried out an independent t - test to determine if there were any differences between the ages of patients that had broken screws and those that did not , and no statistical significance was found , p = 0.740 .
out of 21 cases , screws broke during removal in 5 cases ( 23.8% ) . in 16 out of 21 cases ,
the reasons for hardware removal were infection in 7/21 cases , symptomatic , prominent hardware in 7/21 cases , nonunion in 6/21 cases , and contracture in 1/21 cases .
14 involved titanium alloy and 7 involved stainless steel implants . within the titanium hardware group , in 10 cases removal was uneventful , and in 4 cases , fracture of at least one screw occurred . in comparison , out of the 7 stainless steel hardware removal cases , there was one case that resulted in one or more broken screws .
overall , compared to stainless steel , failure of titanium alloy screws during removal was not found to be statistically significant ( p = 0.61 ) .   in order to determine whether there were any association between the duration of implantation and hardware failure during removal
, cases were divided into two groups : group ( 1 ) duration of hardware implantation was 12 months or less ( mean 7.7 , range two to 12 months ) , and group ( 2 ) : duration of implantation was more than 12 months ( mean 41.6 , range 16 to 74 months ) .
twelve cases had hardware removed within 12 months of implantation and nine cases had hardware removed after 12 months of initial implantation .
bone screws that were removed after 12 months of surgery were more likely to break during removal ( p = 0.046 ) .
when titanium screws were analyzed separately , those removed within 12 months of surgery were more likely to be removed intact as compared to those removed more than 12 months after implantation ( p = 0.003 ) . the small number of stainless steel cases ( seven ) did not warrant statistical calculations .
with respect to anatomic location , there were 12 distal humerus and 15 proximal ulna cases ( table 1 ) .
six cases involved the distal humerus only , nine cases involved the proximal ulna only , and six cases had simultaneous proximal ulna and distal humerus involvement . in one case where titanium screws broke and in one case where stainless steel screws broke , it was unclear where the location was and these cases were discarded from the analysis . in general , bone screw failure was equally likely to occur when removed from the distal humerus and the proximal ulna ( p = 0.28 ) .
hardware failure during removal cases is a commonly seen problem in orthopaedics   ( figure 1 ) .
currently , there is no single hardware removal technique that is uniformly successful , and several different methods may be employed during the same case .
such techniques include the use of screw extractors , trephines , extraction bolts , pliers , and various other devices .
the purpose of this article was to determine the incidence of bone screw failure during hardware removal procedures , and we were interested in comparing titanium and stainless steel bone screws .
in addition , we set out to determine whether the duration of implantation and the anatomic location of the bone screws about the elbow had any association with bone screw failure during removal procedures .
we believe that prior knowledge of the type of metal implanted ( mainly titanium ) and the duration of implantation to be useful information that can help in the preoperative planning of hardware removal procedures .
firstly , this may allow surgeons to request hardware removal kits , thus saving precious operative time .
second , it is our experience that hardware removal procedures are often considered not technically demanding and are often delegated to less experienced surgical staff such as junior residents who may be more likely to break the hardware .
therefore , we believe that experienced staff surgeons should be available during procedures where titanium is being removed . having broken hardware in the elbow may complicate future surgeries in the same region of the limb . with regards to orthopaedic implants
, it is known that both titanium alloy and commercially pure titanium hardware are more predisposed to in situ fracture relative to stainless steel [ 69 ] . as compared to stainless steel ,
titanium alloy is lighter , has a lower modulus of elasticity , and has superior corrosion resistance and biocompatibility , but inferior ductility and notch sensitivity .
the literature search performed for this review did not reveal any previous studies that compare hardware removal from the elbow in vivo for titanium and stainless steel fracture implants .
in contrast to titanium implants remaining in situ for less than 12 months , we observed that the titanium implants remaining in situ for more than 12 months had a tendency to fail during extraction . in this series , it is likely that a combination of titanium alloy 's fatigue properties secondary to notch sensitivity and osseointegration were responsible for this observation .
the fatigue strength of titanium alloy is generally comparable to stainless steel 316l , but notch sensitivity in both commercially pure titanium and titanium alloy has been shown to significantly shorten the fatigue life of these implants in comparison to stainless steel [ 1214 ] .
osseointegration has been observed to occur within 310 months in titanium alloy [ 10 , 11 ] .
the degree of bone ingrowth and on - growth , however , continues to increase for years after initial implantation ( figure 2 ) .
although there have been studies showing evidence of stainless steel osseointegration , it is generally accepted that commercially pure titanium and titanium alloy are more biocompatible and more likely to osseointegrate than stainless steel . in our series , it is likely that as osseointegrataion became more complete , greater removal torques contributed to the failure of titanium alloy screws in this series . given these properties , we postulate that over longer periods and increased loading cycles , the development of micofractures and osseointegration contributed to screw breakage during implant removal .
secondly , the cases studied were not uniform ; there were a wide variety fractures and hardware systems involved .
in addition , due to the small number of cases it was necessary to include multiple surgeons .
in addition , not all x - rays were available for review ; therefore we were not able to account for the type of hardware , such as locking or non locking plate technology . in this study
, there appears to be a time - related association for bone screw failure during removal cases , and for titanium alloy in particular .
this is likely due to the increased bone ingrowth and the adverse effect of notch sensitivity on titanium alloy 's fatigue properties .

Answer:
a retrospective review of 21 patients that underwent bone screw removal from the elbow was studied in relation to the type of metal , duration of implantation , and the location of the screws about the elbow .
 screw failure during extraction was the dependent variable .
 five of 21 patients experienced hardware failure during extraction .
 fourteen patients had titanium alloy implants . in four cases ,
 titanium screws broke during extraction .
 compared to stainless steel , titanium screw failure during removal was not statistically significant ( p = 0.61 ) .
 screw removal 12 months after surgery was more likely to result in broken , retained screws in general ( p = 0.046 ) and specifically for titanium alloy ( p = 0.003 ) .
 bone screws removed from the distal humerus or proximal ulna had an equal chance of fracturing ( p = 0.28 ) .
 there appears to be a time - related association of titanium alloy bone screw failure during hardware removal cases from the elbow .
 this may be explained by titanium 's properties and osseointegration .


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:
potential candidates include l - lactate , -hydroxybutyrate , d - lactate , salicylate , formate and oxalate in toxicological situations , pyroglutamate , semisynthetic penicillins , sulphate and hippurate in renal failure , and occasionally urate and amino acids with catabolic states and total parenteral nutrition .
reports of increased tricyclic acid ( tca ) cycle anions in shock are now emerging . their presence
is often inferred from the anion gap ( ag ) , calculated as [ na ] + [ k ] - ( [ cl ] + [ hco3 ] ) . when its reference range is exceeded , a search for unmeasured anions should commence , irrespective of the overall metabolic acid - base status , because a competing metabolic alkalosis can mask their presence .
likely culprits vary with the clinical scenario , but the search usually starts with l - lactate and -hydroxybutyrate . during this process , stoichiometry is tracked between ag ( measured ag  normal ag ) and the summed concentrations of suspect anions ( always in meq / l , because we are dealing in electrical neutrality ) . if ag
both sensitivity and specificity are reduced by perturbations of albumin ( remembering that albumin negative charge forms the bulk of the normal ag ) , ph , [ ca ] , [ mg ] and [ phosphate ] .
the most promising alternative is the strong ion gap ( sig )   like the ag , the sig quantifies unmeasured anions minus unmeasured cations , but unlike its predecessor it is insulated from variations in [ albumin ] , [ phosphate ] , ph , [ l - lactate ] , [ ca ] and [ mg ] . in the previous issue of critical care , bruegger and
colleagues   combine sig calculations with capillary electrophoresis , and report that anions associated with the tca cycle , specifically citrate and acetate , contribute to the metabolic acidosis of canine haemorrhagic shock .
their data originate from an earlier experiment designed to investigate the benefits of a perflurocarbon - based oxygen carrier during resuscitation from a predefined oxygen debt .
capillary electrophoresis on specimens before shock , during shock and on resuscitation revealed maximal citrate elevations of 1.9 meq / l , whereas the peak acetate increase was 3.4
although these findings fuel ongoing speculation concerning tca anions in shock , several potential confounders are worthy of comment . during preparation , the animals acquired major metabolic perturbations , with severe baseline hypoalbuminaemia ( 1.5 g / dl ) and impressive hyperchloraemia ( 130 mmol / l ) , but ( from the parent study ) only mild anaemia ( 11 g / dl ) .
most surprising in this context was a massive baseline plasma acetate ( 2.4 meq / l ) , which is 40 times the level reported from a previous study in dogs ( 0.06 mmol / l ) .
the postshock acetate peaked at 5.8 meq / l , over 30 times that in the previous report ( 0.19 mmol / l ) . to our knowledge such prodigious acetate levels are unprecedented outside the setting of exogenous administration .
in the parent study , ringer 's solution 15 ml / kg per hour was documented as infused during all but the shock phase .
if this was ringer 's acetate , and if the animals had received both saline ( as stated by bruegger and colleagues ) and ringer 's acetate , then this would explain much .
of relevance is a report that exogenous acetate can elevate hepatic citrate . although the authors acknowledge that they re - infused blood containing citrate phosphate dextrose solution during the shock phase , thus introducing exogenous citrate
a final caveat is that charge and dissociation indices for human albumin used in this study differ from those for canine albumin , although the effect on sig calculations is probably small . until now ,
talk of unmeasured ions in critical illness has largely been speculative , based on discrepancies in ag or sig . nonetheless ,
since the late 1960s reports have emerged of accumulating tca cycle intermediates in shock and dysoxic states . the pattern reported by forni and colleagues   in human metabolic acidosis differed substantially from the findings reported by bruegger and coworkers , with relatively small increases in isocitrate , -ketoglutarate , malate and d - lactate , and in some cases citrate and succinate . only on aggregate were these sufficient to inflate the ag .
it is insufficient to invoke ' tissue stress ' to explain such increases in tca anions .
elevations must be considered within the context of anaplerosis and cataplerosis , which combine to maintain adequate concentrations of tca intermediates .
ag = anion gap ; sig = strong ion gap ; tca = tricyclic acid .

Answer:
evidence is emerging that elevated concentrations of the intermediates of the citric acid cycle may contribute to unmeasured anions in critical illness .
 both the anion gap and the strong ion gap are used as scanning tools for recognition of these anions .
 the mechanisms underlying these elevations and their significance require further clarification .


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 dissemination of hepatitis viruses among patients in hemodialysis ( hd ) centers is one of the most important causes of morbidity and mortality in end stage renal disease patients .
while the introduction of vaccination programs and isolation of hd machines have limited the spread of hbv infection , its prevalence rates continue to be unacceptably high in most hd centers .
prevalence of positive hepatitis b surface antigen ( hbsag ) ranged between 1.3% and 14.6% in asia - pacific countries and 13.3% in turkey [ 2 , 3 ] .
hepatitis c virus ( hcv ) is also a major cause of liver disease in hd patients .
prevalence of hcv in hd wards has been reported from 5% to 60% in different countries .
high risk behaviors and blood transfusion are not the usual routes of hcv transmission in hd patients . environment of hd and failure to follow the safety measures for infection control may be the main cause of hcv dissemination in these centers .
accordingly the kidney disease improving global outcome ( kdigo ) in 2008 and the center for disease control and prevention ( cdc ) in 2001 advised protocols for infection control in hd centers .
principally , these recommendations are based on : ( a ) compliance with infection control protocols by healthcare professionals ( hcp ) , ( b ) performing viral serological tests periodically , and ( c ) continuing training courses for personnel [ 7 , 8 ] .
the main practical points to be considered are cleaning the rooms and patients ' area , disinfection of instruments , correct drug preparation , and regular hand hygiene [ 9 , 10 ] .
appropriate staff training and regular monitoring for hepatitis viruses are also mandatory . in a study from saudi arabia , by utilization of these recommendations , no new case of hcv was found in a period of 2 years .
viral hepatitis infections are still the challenging problem in hd centers in iran . in a review by alavian et al .
serologic markers of hbv and hcv showed a declining trend from 3.8% and 14.4% to 2.6% and 4.5% , respectively , in recent years , but it varies in different parts of the country . in our recent report ,
seroprevalence of hcv , hbv , and hcv - hbv coinfection was 7% , 7% , and 1.7% , respectively , in hd centers in kerman province .
ministry of health recommended universal anti - infective standard precautions to all hd centers but they are not supervised officially . in order to clarify the contributing risk factors for higher viral transmission in this part of country , this study was conducted to determine the compliance rate of hcp with safety recommendations of kdigo and cdc in southeast of iran .
this cross - sectional study was carried out in seven hd centers around the whole province of kerman , in 2011 .
out of 208 hd patients , 91 cases were under healthcare services in kerman city , the center of the province and the remained 117 cases were distributed in other 6 cities .
the data were collected by using a check list based on the safety recommendations of cdc and kdigo protocols .
these recommendations are a major part of educational program both at the beginning of work and also during the annual retraining courses for hd personnel in iran .
the content of the check list comprised of three parts : ( a ) necessary care taken by the hcp ( 18 items ) , ( b ) periodic viral serological assessment ( 4 items ) , and ( c ) participation of hcp in retraining courses ( 4 items ) . the first part of the study was observed during working hours .
after the first part finished , the other two parts were assessed by interviewing with the hcp and reviewing the documents .
we defined the rate of observance of recommended protocols by hcp into four categories : ( a ) excellent : 90% , ( b ) good : 8089% , ( c ) adequate : 7079% , and ( d ) weak : less than 69% compared to standard ( 100% ) safety measures by cdc and kdigo protocols .
data were analyzed using spss version15 ( spss inc . , chicago , il , usa ) software .
dialysis was performed in three running times : 138 ( 66.3% ) cases in the morning , 58 ( 27.9% ) cases in the evening , and 12 ( 5.8% ) cases at the night hours .
hcp who worked in dialysis wards were 61 persons ( 36 females , 25 males ) with a mean age of 32.4  11.2 years old .
the first item of this section was the presence of a dedicated clean room in the hemodialysis wards .
the level of adherence of hcp was  adequate to excellent  in 10 items .
 weak adherence  was observed in 7 items : not sharing of trolley to carry patients ' medications ( 29.8% ) , cleaning and disinfecting the shared instruments ( 46.2% ) , using single use materials for many patients ( 52.4% ) , carrying used materials in disposable and nonpermeable containers ( 51.9% ) , not returning of unused materials to the clean room ( 55.3% ) , adherence to adequate hand washing ( 58.7% ) and not drawing drug for injection to many patients from a single vial ( 67.3% ) .
a significant difference was observed for some of the items between working shifts ( table 1 ) .
hbv monitoring including hbs ag detection , hbv vaccination , and regular measurement of hbs antibody ( ab ) titer had been performed in all of the patients .
it covered 74.1% of men and 61.6% of women ( p = 0.063 ) . in case of persistent high alanine aminotransferase ( alt ) level and negative hcv ab , hcv pcr was measured in 2.4% .
compliance of hcp to report the new cases of positive hcv to the local cdc was 92% .
monitoring of viral markers had a significant difference in favor of  other cities  than kerman , the center of the province ( p < 0.001 ) ( table 2 ) .
the percentage of hcp who participated in the annual retraining courses were as hand hygiene practice , 76% ; use of protective instruments by hcp , 76% ; routes of dissemination of viruses , 52% ; methods of correct administration of medications , 47% ( figure 1 ) .
the aim of this study was to assess the rate of compliance of hcp with safety measures for control of hepatitis viruses in hd wards in southeast iran .
compliance of hcp with many items of kdigo and cdc recommendations was adequate to excellent .
the main noncompliant items were : sharing the medications trolleys , no disinfection of instruments , reuse of single use materials , return of unused materials to the clean room , and no adherence to hand hygiene .
hd associated viral hepatitis are a challenging health problem around the world and especially in developing countries such as iran .
prevalence of hbv in iranian general population declined to 2.6% due to public hbv vaccination and improved public health awareness in recent years .
hcv prevalence is low in iranian general population and is estimated to be less than 1% . on the other hand , prevalence of hcv and hbv in hd wards in iran has been reported 524% and 7% , respectively [ 12 , 14 ] .
it seems that poor compliance with infection control measures and inadequate disinfection of hd equipments play a major role in hepatitis virus dissemination .   in several studies hd environment was the most important factor for hepatitis virus transmission .
it is highly recommended that medicines should be prepared in clean areas away from dialysis apparatus and served in separate trays for different patients .
multidoses vials should not be used and the drugs should be carried in separate trolleys for each patient [ 17 , 18 ] . based on a survey on hd centers from usa in 2002 , hbv incidence was higher in centers with inappropriate drug preparation . in our study ,
preparation and carrying medicines were served inadequately and they need to be revised by hd staffs .
hd wards equipments including bed , chair and external surfaces of the dialysis apparatus and instruments like scissors , stethoscopes , and blood pressure cuffs should be cleaned and in cases should be disinfected for every patient .
these items were also among the other  weak  adherent points in our study .
hand hygiene practices are mandatory for prevention of viral spreading . in our study , wearing of gloves by personnel was excellent ( 98% ) but they had a weak compliance rate with hand washing ( 58% ) .
similar results have indicated in other studies [ 18 , 21 , 22 ] . in girou
study , the rate of compliance with hand hygiene was 37% , and gloves were immediately removed after patient care in 33% .
showed that the dialysis staff adhered to hand washing and changing gloves in 57% before starting dialysis , in 55% between injections of medications to different patients , and in 47% when changing from one patient to another .
monitoring of viral markers is also essential for prevention of hepatitis viruses . in our study monitoring of hbv infection
was satisfactory but it was weak for hcv , especially at the center of province .
better performance of hcp in  other cities  could be mainly due to low volume of patients and higher ratio of personnel to patients . according to cdc recommendations
all hd patients should be screened and followed for hcv infection by anti - hcv , hcv pcr , and alt level determination . in the present study ,
periodic test of anti - hcv was performed in 69% of patients , but monthly assessment of alt and in case of high alt , pcr request , were the main defect points . in the 2002 survey of us
attention to the primary education of personnel and regular annual retraining courses are the main steps in the elevation of performance of personnel in hemodialysis centers . in a study from sudan , although the knowledge of hcp about infection control measures in hd centers was good ( 81% ) but their performance in patients ' bed was weak ( 823% ) . in our study 4776% of personnel
although there is a decreasing trend in the frequency of viral hepatitis in iran , it seems that still hd patients have a higher risk of infections mainly due to ignoring of safety measures to minimize the risk of transmission .
emphasis on observance of standard infection control recommendations , retraining of hcp , and official supervision on performance of hd centers would be effective steps to reduce the viral transmission .

Answer:
introduction . noncompliance with the recommended infection control measures by the healthcare professionals ( hcps ) plays a major role in transmission of hepatitis b ( hbv ) and hepatitis c ( hcv ) viruses in hemodialysis ( hd ) wards .
 this study aimed to determine the compliance rate of the hcp with safety measures in the hd wards in southeast iran .
 patients and methods . a total of 208 patients were enrolled .
 adherence of hcps with standard infection control measures was assessed .
 results .
 sixty - one hcps with a mean age of 32.4  11.2 years old were responsible for healthcare services .
 compliance with the following items was weak : not sharing medications trolley ( 29.8% ) , disinfecting the shared instruments ( 46.2% ) , using single use materials for many patients ( 52.4% ) , carrying used materials in disposable containers ( 51.9% ) , not returning of unused materials to the clean room ( 55.3% ) , and adherence to hand washing ( 58.7% ) .
 periodic monitoring for hbv and hcv was performed on 100% and 69.7% of the patients , respectively .
 less than 2/3 of hcps participated in the retraining courses .
 conclusion .
 compliance of hcps with safety measures for viral hepatitis prevention was partly inadequate in hd wards .
 emphasis on retraining of hcps and official supervision would be effective steps in the reduction of viral dissemination .


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 chia ( salvia hispanica ) seed was used as an offering to the aztec gods , and , because of its religious use , it essentially disappeared for 500 years .
this is an annual herbaceous plant belonging to the lamiaceae or labiatae family . in pre - columbian times , it was one of the basic foods of several central american civilizations , less important than corn and beans , but more important than amaranth .
the chemical composition reports contents of protein ( 1525% ) , fats ( 3033% ) , carbohydrates ( 2641% ) , dietary fiber ( 1830% ) , and ash ( 4 - 5% ) .
chia seeds have been investigated and recommended due to their high levels of proteins , antioxidants , dietary fiber , vitamins , and minerals but particularly due to their oil content with the highest proportion of -linolenic acid ( -3 ) compared to other natural sources known to date .
chia seeds contain up to 39% of oil , which has the highest known content of -linolenic acid , up to 68% .
chia seed gum has the potential for industrial use because of its slimy properties , evident even at very low concentration , and because the plant , native to america , grows well in semiarid regions that have few practical plants .
chia gum begins to emerge from seeds as soon as they are placed in water .
the exudate is either partially cross - linked or is bound to the seed surface , since it is not easily separated from the seed .
separation can be accomplished by strong stirring , preferably in the presence of sand to aid in dislodgment or cleavage of insolubilizing bonds . for research purposes ,
gum has been removed by extraction of seeds with a 6  m urea solution .
chia gum is composed of -d - xylopyranosyl , -d - glucopyranosyl , and 4-o - methyl--d - glucopyranosyluronic acid unit in the ratio 2  :  1  :  1 . the polysaccharide seems to consist of a repeating unit .
extracted gum has a slimy , mucilaginous character at very low concentrations , giving it wide potential use in a variety of industrial applications , especially in certain foods and food preparations .
the objective of the present study was to determine the physicochemical properties of fatted and defatted gums from chia ( salvia hispanica ) seeds .
chia ( s. hispanica l. ) seeds were obtained in the yucatan state of mexico .
reagents were of analytical grade and purchased from j. t. baker ( phillipsburg , nj , usa ) , sigma ( sigma chemical co. , st .
louis , mo , usa ) , merck ( darmstadt , germany ) , and bio - rad ( bio - rad laboratories , inc .
seeds of chia were submitted to gum extraction with water at a 1  :  20 ratio ( w / v ) for 30  min and at a 50c temperature .
after that , the suspension was milled in a mixer and then it was boiled again at 50c under stirring for 15  min .
the crude mixture , containing water , gum , and seeds , was centrifuged at 9460  g at 15c for 3  h. the recovered gum ( fcg ) was dried at 40c for 24 hours and milled .
one portion of the recovered gum was partly defatted ( pdcg ) in a soxhlet .
standard aoac   procedures were used to determine nitrogen ( method 954.01 ) , fat ( method 920.39 ) , ash ( method 925.09 ) , crude fiber ( method 962.09 ) , and moisture ( method 925.09 ) contents in the fatted and defatted chia gums .
approximate water absorption capacity was first determined by weighing out 0.1  g ( d.b . ) of sample , adding water until saturation ( approximately 5  ml ) , and centrifuging at 2000  g for 10  min in a beckman gs-15r centrifuge .
approximate water absorption capacity was calculated by dividing the increase in sample weight ( g ) by the quantity of water needed to complete original sample weight to 15  g. water absorption capacity ( wabc ) was then determined by placing samples in four tubes , adding different quantities of water to bracket the measurement ( 1.5 and 0.5  ml water above original weight and 1.5 and 0.5  ml water below ; one in each tube ) , agitating vigorously in a vortex for 2  min , and centrifuging at 2000  g for 10  min in a beckman gs-15r centrifuge .
average water absorbed was calculated and the wabc was calculated , expressed as g water absorbed per g of sample .
briefly , 0.1  g ( d.b . ) of sample was placed in an equilibrium microenvironment at 98% relative humidity , generated by placing 20  ml of saturated potassium sulfate saline solution in tightly sealed glass flasks and placing these in desiccators at 25c .
the sample was left in the microenvironment until reaching constant weight ( 72 h ) .
briefly , 0.1  g ( d.b . ) of sample was weighed and then stirred into 20  ml of distilled water or corn oil ( mazola , cpi international ) for one minute .
these fibrous suspensions were then centrifuged at 2200  g for 30  min and the supernatant volume was measured .
water - holding capacity was expressed as g of water held per g of sample , and oil - holding capacity was expressed as g of oil held per g of gum .
corn oil density was 0.92  g / ml . apparent viscosity was evaluated using an adaptation of the li and chang   method , using a brookfield viscometer model dv - ii ( brookfield engineering lab . , stoughton , ma ) with spindle 27 ( for small samples ) and share rate range from 2.5 to 100  rpm at 25c .
the samples were dispersed in water to 0.5 , 1.0 , 1.5 , 2.0 , and 2.5% ( w / v , db ) .
the results were expressed in pa.s and data was fixed to an ostwald - de waele model to determine the consistency index ( k ) and flow behavior index ( n ) .
this percentage was lower than reported by sciarini et al .   in gleditsia triacanthos seeds ( 11.934.16% ) .
however , the chia gum 's yield was higher than reported by oomah et al .   in flaxseed ( 3.68% ) .
the proximal composition ( table 1 ) showed that pdcg registered a higher content of protein , ash , and nfe than fcg .
the fiber content of fcg ( 28.96% ) was similar to that reported by vazquez - ovando et al .   in a fiber - rich fraction of chia seeds ( 29.56% ) .
the moisture content of both gums was similar to that reported by kader et al .   in acacia glomerosa ( 9.09% ) but lower than reported in guar gum ( 10.36% ) , xanthan gum ( 11.08% ) , and gleditsia triacanthos ( 14.08% ) .
with respect to the nfe content , both gums registered lower values than reported by vazquez - ovando et al .   in a fiber - rich fraction of chia seeds ( 34.52% ) .
however , the ash content of fcg and pdcg was higher than that reported by kader et al .   in arabic gum ( acacia senegal , 3.6% ) although lower than reported by sciarini et al .   in xanthan gum ( 9.35% ) .
the protein content of both gums was higher than registered in corn gum ( 5.1% ) and mesquite gum ( 5.8% ) , this last one with important emulsifying properties attributed to its protein content according to bosquez . in this respect ,
establish that hydrocolloids rich in protein , such as gelatin , arabic gum , and mesquite , are good stabilizers because they have sufficient hydrophobic groups to act as bonding points as well as hydrophilic groups that reduce surface tension in a liquid - liquid or liquid - gas interface . on the other hand , yadav et al .
establish that the lipid content in the gums may also play an important role in stabilization of oil - water emulsions .
however , bosquez   established that carbohydrates avoid flocculation and coalescence of oil droplets to extend in the aqueous solution .
these findings suggest that fcg and pdcg could act as good emulsifiers and stabilizers in the food industry .

water absorption capacity is indicative of a structure 's aptitude to spontaneously absorb water when placed in contact with a constantly moist surface or when immersed in water .
water adsorption capacity is the ability of a structure to spontaneously adsorb water when exposed to an atmosphere of constant relative humidity .
wabc was higher in fcg ( 44.08  g / g of sample ) than pdcg ( 36.2  g / g of sample ) .
the high values of wabc obtained here could be due to the proteins present in the gums , which would have a large number of exposed hydrophilic sites interacting with water .
the wabc of fcg and pdcg was higher than reported by vzquez - ovando et al .   in a fiber - rich fraction of chia seeds ( 11.73  g / g of sample ) , who establish
that fiber content is an important factor in the increment of this property for its capacity to form gels and to hold water ; this justifies the higher value of wabc in fcg .
on the other hand , pdcg ( 0.84  g / g of sample ) registered a higher value of wadc than fcg ( 0.27  g / g of sample ) .
the wadc of dcg was also higher than registered by vzquez - ovando et al .   in a fiber - rich fraction of chia seeds ( 0.3  g / g of sample ) , similar to that reported in carrots ( 0.82  g / g of sample ) but lower than the value registered in beet bagasse ( 1.58  g / g of sample ) .
however , whc of both gums was higher than that reported by vzquez - ovando et al .   and baquero and bermdez   in a fiber - rich fraction of chia seeds ( 15.41  g / g of fiber ) and passion fruit peel ( 8.7  g / g of fiber ) , respectively .
a similar behavior was observed with orange waste ( 7.658.23  g / g of fiber ) . soluble fiber and the denaturalized proteins
may have increased the whc of both gums , thus enhancing the swelling ability , an important function of proteins in preparation of viscous foods such as soups , gravies , dough , and baked products . on the other hand
, fcg showed a higher ohc than pdcg , which might be related to its higher value of fat .
however , both gums registered higher ohc values than those registered in guar and xanthan gum ( 46  g oil / g fiber ) although similar to that reported in arabic gum ( 8 - 9  g oil / g fiber ) .
this functional property has been attributed to the physical entrapment of oil for molecules such as lipids and proteins . for the above mentioned
, the ohc registered in chia gums could be due to protein and fat contents as well as factors as particle size and the absence of hemicellulose .
chia gum seems to possess an adequate fat absorption capacity , allowing it to play an important role in food processing , since fat acts on flavor retainers and increases the mouth feel of foods .

both gums showed a non - newtonian behavior where viscosity presented a relation directly proportional to the concentration and inversely proportional to the shear rate . the maximum viscosity reached between both gums
was registered by pdcg ( 55.4  pas ) at 2.5% . in general , pdcg registered a higher viscosity profile than fcg suggesting that the fat content was the principal factor that generated this behavior . at this respect ,
report that gums with higher oil absorption as arabic gum show less viscosity ( 2.34  pas at 3.8% ) . according to table 2 ,
the rheological behavior of the fcg and pdcg dispersions was a shear thinning or pseudoplastic type due to registered values of n < 1 .
the results suggest the use at low concentrations of dcg in products as yoghurts , sauces , toppings , and pastries among others that require high viscosity , whilst fcg could be used in sauces , mayonnaises , and meat products as emulsifying and stabilizer .
the results obtained here show that chia gums present interesting physicochemical properties for the food industry .
the partly defatted chia gum showed a very good ability to water holding ( 110.5  g / g ) ; however , their ability of oil holding ( 11.67  g / g ) and water absorption ( 36.26  g / g ) was minor compared to the fatted chia gum , which provided a greater retention of oil holding ( 25.79  g / g ) and water absorption ( 44.08  g / g ) .
rheological behavior of gums was shear thinning or pseudoplastic type . from a functional point of view
, chia gum also is an important food ingredient due its emulsifier and stabilizer potentials .

Answer:
chia ( salvia hispanica l. ) constitutes a potential alternative raw material and ingredient in food industry applications due to its dietary fiber content .
 gum can be extracted from its dietary fiber fractions for use as an additive to control viscosity , stability , texture , and consistency in food systems .
 the gum extracted from chia seeds was characterized to determine their quality and potential as functional food additives .
 the extracted chia gum contained 26.2% fat and a portion was submitted to fat extraction , producing two fractions : gum with fat ( fcg ) and gum partly defatted ( pdcg ) .
 proximal composition and physicochemical characterization showed these fractions to be different ( p < 0.05 ) .
 the pdcg had higher protein , ash , and carbohydrates content than the fcg , in addition to higher water - holding ( 110.5  g water / g fiber ) and water - binding capacities ( 0.84  g water / g fiber ) .
 the fcg had greater oil - holding capacity ( 25.7  g oil / g fiber ) and water absorption capacity ( 44  g water / g fiber ) . in dispersion trials ,
 the gums exhibited a non - newtonian fluid behavior , specifically shear thinning or pseudoplastic type .
 pdcg had more viscosity than fcg .
 chia seed is an excellent natural source of gum with good physicochemical and functional qualities , and is very promising for use in food industry .