***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: Background Diabetes may confer an increased risk for the cardiovascular health effects of particulate air pollution , but few human clinical studies of air pollution have included people with diabetes . Ultrafine particles ( UFP , ≤100 nm in diameter ) have been hypothesized to be an important component of particulate air pollution with regard to cardiovascular health effects . Methods 17 never-smoker subjects 30–60 years of age , with stable type 2 diabetes but otherwise healthy , inhaled either filtered air ( 0–10 particles/cm3 ) or elemental carbon UFP ( ~107 particles/cm3 , ~50 ug/m3 , count median diameter 32 nm ) by mouthpiece , for 2 hours at rest , in a double-blind , r and omized , crossover study design . A digital 12-lead electrocardiogram ( ECG )  was recorded continuously for 48 hours , beginning 1 hour prior to exposure . Results Analysis of 5-minute segments of the ECG during quiet rest showed reduced high-frequency heart rate variability with UFP relative to air exposure ( p = 0.014 ) , paralleled by non-significant reductions in time-domain heart rate variability parameters . In the analysis of longer duration s of the ECG , we found that UFP exposure increased the heart rate relative to air exposure . During the 21- to 45-hour interval after exposure , the average heart rate increased approximately 8 beats per minute with UFP , compared to 5 beats per minute with air ( p = 0.045 ) . There were no UFP effects on cardiac rhythm or repolarization . Conclusions Inhalation of elemental carbon ultrafine particles alters heart rate and heart rate variability in people with type 2 diabetes . Our findings suggest that effects may occur and persist hours after a single 2-hour exposure Previous reports suggest that inflammatory bowel diseases may be accompanied by abnormalities in the neural autonomic profile . We tested the hypotheses that 1 ) an exaggerated sympathetic activity characterizes active ulcerative colitis ( UC ) and 2 ) a reduction of sympathetic activity by clonidine would be associated with clinical changes of UC . In 23 patients with UC and 20 controls , muscle sympathetic nerve activity ( MSNA ) , ECG , blood pressure , and respiration were continuously recorded , and plasma catecholamine was evaluated both at rest and during a 75 degrees head-up tilt . Autonomic profile was assessed by MSNA , norepinephrine , epinephrine , spectral markers of low-frequency ( LF ) cardiac sympathetic ( LF(RR ) ; normalized units ) and high-frequency ( HF ) parasympathetic ( HF(RR ) ; normalized units ) modulation and sympathetic vasomotor control ( LF systolic arterial pressure ; LF(SAP ) ) , obtained by spectrum analysis of the R-R interval and systolic pressure variability . Among UC patients , 16 agreed to be r and omly assigned to 8-wk transdermal clonidine ( 15 mg/wk , 9 subjects ) , or placebo ( 7 patients ) . An autonomic profile , Disease Activity Index ( DAI ) , and endoscopic pattern were compared before and after clonidine/placebo . At rest , MSNA , heart rate ( HR ) , LF(RR ) , LF/HF , and LF(SAP ) were higher and HF(RR ) was lower in patients than in controls . Tilt decreased HF(RR ) and increased MSNA and LF(RR ) less in patients than in controls . Clonidine decreased HR , MSNA , epinephrine , LF(RR ) , and increased HF(RR ) , whereas placebo had no effects . Changes of the autonomic profile after clonidine were associated with reduction of DAI score . An overall increase of sympathetic activity characterized active UC . Normalization of the autonomic profile by clonidine was accompanied by an improvement of the disease Epidemic of diabetes , affecting about 3–5 % of Western population s , is one of the main threats to human health in the 21st century ( 1 ) . Changes in the human environment , behavior , and lifestyle have result ed in a dramatic increase in the incidence and prevalence of diabetes in people with genetic susceptibility to diabetes . The global number of people with diabetes was 151 million in 2000 , and it is projected to increase to 221 million in 2010 ( an increase of 46 % ) both in developed and developing countries ( 2 ) . Chronic hyperglycemia leads to many long-term complications in the eyes , kidneys , nerves , heart , and blood vessels .  Individuals with pre-diabetes , undiagnosed type 2 diabetes , and long-lasting type 2 diabetes are at high risk of all complications of macrovascular disease , coronary heart disease ( CHD ) , stroke , and peripheral vascular disease . More than 70 % of patients with type 2 diabetes die of cardiovascular causes ( 3 ) . Therefore , the epidemic of type 2 diabetes will be followed by an epidemic of diabetes-related cardiovascular disease ( CVD ) . Over the years , epidemiological studies have produced important information on the prevalence and incidence of diabetes complications in different population s. They have also given important information on different risk factors determining susceptibility to diabetes complications ( Fig. 1 ) . This information is crucial for mechanistic studies in physiology at the tissue level and for molecular biology studies at the cellular level . A good example is glycated hemoglobin . Several studies have indicated that glycated hemoglobin is associated with diabetes complications in prospect i ve epidemiological studies . That information has been crucial for the planning of clinical trials to test the hypothesis that the treatment of chronic hyperglycemia leads to reduction in long-term diabetes complications . Moreover , information from epidemiology has led to several mechanistic studies and the elucidation of molecular level insights how insulin resistance and hyperglycemia lead to diabetes complications . We examined whether an injection of intravenous insulin and intravenous glucose would affect frequency-domain measures of heart rate variability ( HRV ) , i.e. , the high-frequency ( HF- ) b and and the ratio of the low frequency ( LF- ) to the HF-b and in healthy humans . Using a classical conditioning protocol , we also assessed whether the measures of HRV are subject to classical conditioning . Thirty healthy men were divided into three groups , given a conditioned stimulus ( CS ) and an intravenous injection of either insulin ( 0.05IU/kg ) in Group 1 , glucose ( 15 % , 0.5g/kg ) in Group 2 , or placebo ( physiological saline [ 0.9 % ] ) in Group 3 during the 4-day acquisition phase . All subjects were given an olfactory CS ( rosewood-peppermint smell ) and placebo injection on day 5 ( test ) . Due to their high inter-individual variability , HF and LF/HF-ratio were analysed by intragroup comparisons , using a pre-injection baseline interval ( min -15 to -5 ) , and three functional post-injection intervals : a ) the interval to the maximum insulin level , i. e. insulin peak ( min 0 - 5 ) in Groups 1 and 2 , b ) the interval to the maximum of insulin-induced hypoglycaemia ( min 20 - 25 ) in Group 1 , and c ) the end of the session ( min 70 - 75 ) . On days 1 to 4 , we found significant increases of the HF-b and from baseline to interval min 0 - 5 in Group 1 , and an even more pronounced increase in the glucose-treated Group 2 . At the test ( Day 5 ) , both experimental groups responded with an HF-increase in the interval of the former insulin peak , and also at the other measurement intervals , reflecting some general increase of vagal activity remaining as a conditioned response . On days 1 to 4 , the HF-b and was positively correlated with the change of peripheral insulin levels in Group 1 , reaching statistical significance on days 3 and 4 . This pattern only emerged in tendency on Day 4 in Group 2 . In conclusion , insulin triggers an increase in parasympathetic tone at maximum hyperinsulinaemia , and our data support the notion that this response pattern can become classically conditioned Introduction The need for colonoscopy is common among diabetics . In this study , we aim ed to evaluate the effect of autonomous neuropathy on bowel preparation in type 2 diabetes mellitus ( DM ) patients . Material s and methods The study population consisted of 45 patients with DM and 48 non-diabetic , age- and sex-matched subjects .  All colonoscopies were performed 5 h after the last dose of sodium phosphate . Colonoscopists rated the bowel preparation quality during the procedure using the Aronchick scale . All patients underwent a detailed cardiologic examination and 24-h Holter rhythm monitoring . Orthostatic hypotension and impairment in heart rate variability were accepted as indicators of autonomous neuropathy . Results Gender , age , blood pressure , and heart rates did not differ significantly between groups ( p > 0.05 ) . Autonomous neuropathy was detected in 14 ( 31.1 % ) patients in the DM group and in two ( 4.2 % ) in the control group ( p < 0.05 ) . Optimal bowel cleansing was achieved in 93.8 % of controls and 73.3 % of diabetics ; bowel cleansing was suboptimal in 26.7 % of diabetics and 6.2 % of controls ( p < 0.05 ) . Optimal bowel cleansing was achieved in six of 14 ( 42.8 % ) diabetic patients with autonomous neuropathy ; however , optimal bowel cleansing was achieved in 27 of 31 ( 87.1 % ) diabetic patients without autonomous neuropathy ( p < 0.05 ) . Although optimal bowel cleansing was more prevalent among control patients than in diabetic patients without autonomous neuropathy , the difference was not significant ( 87.1 % vs 93.8 % ; p > 0.05 ) . Conclusion These data suggest that optimal bowel cleansing is poorer in diabetics with autonomous neuropathy than in those without autonomous neuropathy and controls Objectives Appropriate reporting is central to the application of findings from research to clinical practice . The Strengthening the Reporting of Observational Studies in Epidemiology ( STROBE ) recommendations consist of a checklist of 22 items that provide guidance on the reporting of cohort , case – control and cross-sectional studies , in order to facilitate critical appraisal and interpretation of results . STROBE was published in October 2007 in several journals including The Lancet , BMJ , Annals of Internal Medicine and PLoS Medicine . Within the framework of the revision of the STROBE recommendations , the authors examined the context and circumstances in which the STROBE statement was used in the past . Design The authors search ed the Web of Science data base in August 2010 for articles which cited STROBE and examined a r and om sample of 100 articles using a st and ardised , piloted data extraction form . The use of STROBE in observational studies and systematic review s ( including meta-analyses ) was classified as appropriate or inappropriate . The use of STROBE to guide the reporting of observational studies was considered appropriate . Inappropriate uses included the use of STROBE as a tool to assess the method ological quality of studies or as a guideline on how to design and conduct studies . Results The authors identified 640 articles that cited STROBE . In the r and om sample of 100 articles , about half were observational studies ( 32 % ) or systematic review s ( 19 % ) . Comments , editorials and letters accounted for 15 % , method ological articles for 8 % , and recommendations and narrative review s for 26 % of articles . Of the 32 observational studies , 26 ( 81 % ) made appropriate use of STROBE , and three uses ( 10 % ) were considered inappropriate . Among 19 systematic review s , 10 ( 53 % ) used STROBE inappropriately as a tool to assess study quality . Conclusions The STROBE reporting recommendations are frequently used inappropriately in systematic review s and meta-analyses as an instrument to assess the method ological quality of observational studies To investigate the effects of obesity and weight loss on cardiovascular autonomic function , we examined 28 obese patients referred for weight-reducing gastroplasty , 24 obese patients who received dietary recommendations , and 28 lean subjects .  Body weight , blood pressure , and 24-hour urinary norepinephrine excretion were measured , and time and frequency domain indexes of heart rate variability ( HRV ) were obtained from 24-hour Holter recordings . A measure of long-term HRV , the SD of all normal RR intervals ( SDANN ) , was used as an index of sympathetic activity and the high-frequency ( HF ) component of the frequency domain , reflecting short-term HRV , as an estimate of vagal activity . All 3 study groups were investigated at baseline , and the 2 obese groups were reexamined at 1-year follow-up . Obese patients had higher blood pressure , higher urinary norepinephrine excretion , and attenuated SDANN and HF values than lean subjects ( p < 0.01 ) . Obese patients treated with surgery had a mean weight loss of 32 kg ( 28 % ) , whereas the obese group treated with dietary recommendations remained weight stable ( p < 0.001 ) . At follow-up the weight-loss group displayed decreases in blood pressure and norepinephrine excretion and showed increments in SDANN 
    Output:
    
Levels of blood glucose and HbA1c were associated with several HRV parameters , as well as Time from diagnosis of T2DM .
T2DM was associated with an overall decrease in the HRV of T2DM patients .
Both sympathetic and parasympathetic activity were decreased , which can be explained by the deleterious effects of altered glucose metabolism on HRV , leading to cardiac autonomic neuropathy