***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: There is evidence from studies in animals that the effects of both fat and CCK on gastrointestinal function and energy intake are attenuated by consumption of a high-fat diet . In humans , the effects of exogenous CCK-8 on antropyloroduodenal motility , plasma CCK , peptide YY ( PYY ) , and ghrelin concentrations , appetite , and energy intake are attenuated by a high-fat diet . Ten healthy lean males consumed  isocaloric diets ( ~15,400 kJ per day ) , containing either 44 % ( high-fat , HF ) or 9 % ( low-fat , LF ) fat , for 21 days in single-blind , r and omized , cross-over fashion . Immediately following each diet ( i.e. , on day 22 ) , subjects received a 45-min intravenous infusion of CCK-8 ( 2 ng.kg(-1).min(-1 ) ) , and effects on antropyloroduodenal motility , plasma CCK , PYY , ghrelin concentrations , hunger , and fullness were determined . Thirty minutes after commencement of the infusion , subjects were offered a buffet-style meal , from which energy intake ( in kilojoules ) was quantified . Body weight was unaffected by the diets . Fasting CCK ( P < 0.05 ) , but not PYY and ghrelin , concentrations were greater following the HF , compared with the LF , diet . Infusion of CCK-8 stimulated pyloric pressures ( P < 0.01 ) and suppressed antral and duodenal pressures ( P < 0.05 ) , with no difference between the diets . Energy intake also did not differ between the diets . Short-term consumption of a HF diet increases fasting plasma CCK concentrations but does not affect upper gut motility , PYY and ghrelin , or energy intake during CCK-8 infusion , in a dose of 2 ng.kg(-1).min(-1 ) , in healthy males OBJECTIVES : Perception of sensations arising from the gastrointestinal tract may be diminished in obese subjects and thus facilitate overeating . Alternatively , excess food intake may cause gastrointestinal ( GI ) symptoms in obese patients . We evaluated the relationship between body mass index ( BMI ) and specific GI symptoms in the community . METHODS : Residents of Olmsted County , MN were selected at r and om to receive by mail one of two vali date d question naires . The association of reported GI symptoms with BMI ( kg/m2 ) was assessed using a logistic regression analysis adjusting for age , gender , psychosomatic symptom score , and alcohol and tobacco use . RESULTS : Response rate was 74 % ( 1,963 of 2,660 ) . The prevalence of obesity ( BMI ≥ 30 kg/m2 ) was 23 % . There was a positive relationship between BMI and frequent vomiting ( p = 0.02 ) , upper abdominal pain ( p = 0.03 ) , bloating ( p = 0.002 ) , and diarrhea ( p = 0.01 ) . The prevalence of frequent lower abdominal pain , nausea , and constipation was increased among obese ( BMI ≥ 30 kg/m2 ) compared to normal weight participants , however , no significant association was found between BMI and these symptoms . CONCLUSIONS : In the community , increasing BMI is associated with increased upper GI symptoms , bloating , and diarrhea . Clarification of the cause- and -effect relationships and the mechanisms of these associations require further investigation Introduction : Intestinal electric stimulation ( IES ) is proposed as a potential tool for the treatment of morbid obesity . Our earlier study showed that IES with one pair of electrodes accelerated intestinal transit and decreased fat absorption in a segment of the jejunum in anesthetized rats . The aims of this study were to assess the effects of IES on whole gut transit and fat absorption in conscious rats , to examine the effects of multi-pairs IES and to explore the cholinergic mechanism behind the effects of IES . Methods : Thirty-eight male rats implanted with serosal electrodes were r and omized into five groups : control without IES , two- or three-pairs IES with short pulses , atropine and atropine plus IES . The whole gut transit and fat remained and emptied from the gut were analyzed after continuous 2-h IES . Results : Two- and three-pairs IES significantly accelerated phenol red ( PR , marker used for transit ) excretion ( analysis of variance ( ANOVA ) , P<0.001 ) . No significant difference was found between two- and three-pairs IES . Two-pairs IES significantly increased the excretion of fat ( P<0.05 ) . Atropine significantly blocked the accelerated transit induced by IES ( ANOVA , P<0.001 ) . Correlation was found between the percentage of PR and fat retained in the whole gut ( r=0.497 , P<0.01 ) . Conclusions : IES accelerates whole gut transit and promotes fat excrement in conscious rats , and these effects are mediated through the cholinergic nerves . These findings are in support of the concept that IES may be a promising treatment option for obesity AIM To clarify the association between physical activity and  gastroesophageal reflux disease ( GERD ) in non-obese and obese people . METHODS A Swedish population -based  cross-sectional survey was conducted . Participants aged 40 - 79 years were r and omly selected from the Swedish Registry of the Total Population .  Data on physical activity , GERD , body mass index ( BMI ) and the covariates age , gender , comorbidity , education , sleeping problems , and tobacco smoking were obtained using vali date d question naires . GERD was self-reported and defined as heartburn or regurgitation at least once weekly , and having at least moderate problems from such symptoms . Frequency of physical activity was categorized into three groups : ( 1 ) " high " ( several times/week ) ; ( 2 ) " intermediate " ( approximately once weekly ) ; and ( 3 ) " low " ( 1 - 3 times/mo or less ) . Analyses were stratified for participants with " normal weight " ( BMI < 25 kg/m² ) , " overweight " ( BMI 25 to ≤ 30 kg/m² ) and " obese " ( BMI > 30 kg/m² ) . Multivariate logistic regression was used to calculate odds ratios ( ORs ) with 95 % confidence intervals ( CIs ) , adjusted for potential confounding by covariates . RESULTS Of 6969 eligible and r and omly selected individuals , 4910 ( 70.5 % ) participated .  High frequency of physical activity was reported by 2463 ( 50 % ) participants , GERD was identified in 472 ( 10 % ) participants , and obesity was found in 680 ( 14 % ) . There were 226 ( 5 % ) individuals with missing information about BMI . Normal weight , overweight and obese participants were similar regarding distribution of gender and tobacco smoking status , while obese participants were on average slightly older , had fewer years of education , more comorbidity , slightly more sleeping problems , lower frequency of physical activity , and higher occurrence of GERD . Among the 2146 normal-weight participants , crude point estimates indicated a decreased risk of GERD among individuals with high frequency of physical activity ( OR : 0.59 , 95 % CI : 0.39 - 0.89 ) , compared to low frequency of physical activity . However , after adjustment for potential confounding factors , neither intermediate ( OR : 1.30 , 95 % CI : 0.75 - 2.26 ) nor high ( OR : 0.99 , 95 % CI : 0.62 - 1.60 ) frequency of physical activity was followed by decreased risk of GERD . Sleeping problems and high comorbidity were identified as potential confounders . Among the 1859 overweight participants , crude point estimates indicated no increased or decreased risk of GERD among individuals with intermediate or high frequency of physical activity , compared to low frequency . After adjustment for confounding , neither intermediate ( OR : 0.75 , 95 % CI : 0.46 - 1.22 ) nor high frequency of physical activity were followed by increased or decreased risk of GERD compared to low frequency among nonobese participants . Sleeping problems and high comorbidity were identified as potential confounders for overweight participants . In obese individuals , crude ORs were similar to the adjusted ORs and no particular confounding factors were identified . Intermediate frequency of  physical activity  was associated with a decreased occurrence of GERD compared to low frequency of physical activity ( adjusted OR : 0.41 , 95 % CI : 0.22 - 0.77 ) . CONCLUSION Intermediate frequency of physical activity might decrease the risk of GERD  among obese individuals , while no influence of physical activity on GERD was found in non-obese people Objectives : The aim of the study was to determine the frequency of  functional constipation according to the Rome III criteria in children with morbid obesity and to evaluate by measuring colonic transit times ( CTTs ) whether decreased colonic motility is present in these children . Patients and Methods : Ninety-one children with morbid obesity ages 8 to 18 years , entering a prospect i ve , r and omized controlled study evaluating the effect of an outpatient versus inpatient treatment program of obesity , participated . All of the children filled out a st and ardized question naire regarding their bowel habits , and  CTTs were measured using radioopaque markers . Food diaries were also recorded to evaluate their diet . Results : A total of 19 children ( 21 % ) had functional constipation according to the Rome III criteria , whereas 1 child had functional nonretentive fecal incontinence . Total CTT exceeded 62 hours in only 10.5 % of the children with constipation , and among them , 2 had a total CTT of > 100 hours . In the nonconstipated group 8.3 % had a delayed CTT . Furthermore , no difference was found between the diet of children with or without constipation , specifically not with respect to fiber and fat intake . Conclusions : Our study confirms a high frequency of functional constipation in children with obesity , using the Rome III criteria . However , abnormal colonic motility , as measured by CTT , was delayed in only a minority of patients . No relation was found between constipation in these children and fiber or fat intake Accommodation of the stomach consists of a vagally mediated relaxation of the proximal stomach , providing the meal with a reservoir . Our aim was to study whether , similar to other vagally mediated processes , the accommodation reflex is also determined by cephalic , oropharyngeal , gastric , and intestinal phases . Eleven healthy subjects underwent in r and omized order five gastric barostat studies and two satiety drinking tests . In all studies , isobaric tone measurements ( at minimal distending pressure + 2 mmHg ) were performed 20 min before and 20 min after a nutrient stimulus . The stimuli included only visual and olfactory exposure to a meal ( cephalic stimulation ) , taking liquid nutrient in the mouth without swallowing ( sham feeding ) , ingestion of a 200-ml 300-kcal nutrient meal with blocked outflow to the pylorus ( gastric retention ) , and meal infusion through a nasointestinal tube ( duodenal instillation ) , or normal ingestion ( control ) . During satiety testing , subjects ingested liquid nutrient at a fixed rate of 15 ml/min until maximum satiety , with an inflated or deflated intrapyloric balloon assembly . Progressively bigger gastric relaxatory responses were seen with cephalic stimulation ( 18 + /- 19 ml ) , sham feeding ( 54 + /- 21 ml ) , gastric retention ( 95 + /- 47 ) , duodenal instillation ( 144 + /- 33 ) , and control ( 232 + /- 33 ml ) . The amount of nutrient ingested at maximum satiety was significantly lower with an inflated intrapyloric balloon ( 1,223 + /- 103 vs. 1,392 + /- 124 ml , P < 0.05 ) . The accommodation reflex in humans lacks a cephalic phase , but it can be activated from the oropharynx , the stomach , and the duodenum . Blocking passage to the duodenum significantly decreases the amplitude of the accommodation reflex and induces early satiety BACKGROUND AND AIMS Obesity has been associated with gastroesophageal reflux disease ( GERD ) and its complication , but the mechanism is unclear . We evaluated the association between obesity and function of lower esophageal sphincter ( LOS ) in subjects without GERD . METHODS We prospect ively recruited consecutive obese ( BMI > 30 ) patients referred for weight reduction procedure and age- and sex-matched overweight ( BMI 25 - 30 ) and normal weight ( BMI > or = 20 and < 25 ) subjects . Exclusion criteria included esophagitis , reflux symptoms , use of proton pump inhibitor , hiatus hernia > 2 cm , and diabetes mellitus with microvascular complication . All participants underwent combined 2-hour postpr and ial esophageal manometry and pH monitoring after a st and ard test meal followed by 24-hour ambulatory pH monitoring . RESULTS Eighty-four subjects ( obese , 28 ; overweight , 28 ; normal weight , 28 ) were studied . All 3 groups had comparable mean LOS pressure , LOS length , and peristaltic function . During the postpr and ial 
    Output:
    
Major findings include supportive evidence for increased gastroesophageal reflux disease and esophageal motility disorders in obesity , and a rapid gastric emptying time seen in obese individuals .
The proximal small intestinal transit seems to be increased in obesity and this may be secondary to efficient nutrient absorption and subsequent lack of nutrient-induced satiety signals conveyed from the small intestine .
In obesity , there is some evidence for delayed colonic transit as well as a reduction in colonic serotonin availability .
The molecular mechanisms underlying altered motility in obesity could be secondary to reduced cannabinoids or its receptor cannabinoid receptor 1 ( CB1 ) expression as well as due to loss of neuronal nitric oxide synthase ( nNOS ) neurons .