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991.

Background

BNP has been extensively evaluated to determine short- and intermediate-term prognosis in patients with acute coronary syndrome, but its role in long-term mortality is not known.

Objective

To determine the very long-term prognostic role of B-type natriuretic peptide (BNP) for all-cause mortality in patients with non-ST segment elevation acute coronary syndrome (NSTEACS).

Methods

A cohort of 224 consecutive patients with NSTEACS, prospectively seen in the Emergency Department, had BNP measured on arrival to establish prognosis, and underwent a median 9.34-year follow-up for all-cause mortality.

Results

Unstable angina was diagnosed in 52.2%, and non-ST segment elevation myocardial infarction, in 47.8%. Median admission BNP was 81.9 pg/mL (IQ range = 22.2; 225) and mortality rate was correlated with increasing BNP quartiles: 14.3; 16.1; 48.2; and 73.2% (p < 0.0001). ROC curve disclosed 100 pg/mL as the best BNP cut-off value for mortality prediction (area under the curve = 0.789, 95% CI= 0.723-0.854), being a strong predictor of late mortality: BNP < 100 = 17.3% vs. BNP ≥ 100 = 65.0%, RR = 3.76 (95% CI = 2.49-5.63, p < 0.001). On logistic regression analysis, age >72 years (OR = 3.79, 95% CI = 1.62-8.86, p = 0.002), BNP ≥ 100 pg/mL (OR = 6.24, 95% CI = 2.95-13.23, p < 0.001) and estimated glomerular filtration rate (OR = 0.98, 95% CI = 0.97-0.99, p = 0.049) were independent late-mortality predictors.

Conclusions

BNP measured at hospital admission in patients with NSTEACS is a strong, independent predictor of very long-term all-cause mortality. This study allows raising the hypothesis that BNP should be measured in all patients with NSTEACS at the index event for long-term risk stratification.  相似文献   
992.
Chronic nicotine exposure (CNE) alters synaptic transmission in the ventral tegmental area (VTA) in a manner that enhances dopaminergic signaling and promotes nicotine use. The present experiments identify a correlation between enhanced production of the endogenous cannabinoid 2-arachidonoylglycerol (2-AG) and diminished release of the inhibitory neurotransmitter GABA in the VTA following CNE. To study the functional role of on-demand 2-AG signaling in GABAergic synapses, we used 1,2,3-triazole urea compounds to selectively inhibit 2-AG biosynthesis by diacylglycerol lipase (DAGL). The potency and selectivity of these inhibitors were established in rats in vitro (rat brain proteome), ex vivo (brain slices), and in vivo (intracerebroventricular administration) using activity-based protein profiling and targeted metabolomics analyses. Inhibition of DAGL (2-AG biosynthesis) rescues nicotine-induced VTA GABA signaling following CNE. Conversely, enhancement of 2-AG signaling in naïve rats by inhibiting 2-AG degradation recapitulates the loss of nicotine-induced GABA signaling evident following CNE. DAGL inhibition reduces nicotine self-administration without disrupting operant responding for a nondrug reinforcer or motor activity. Collectively, these findings provide a detailed characterization of selective inhibitors of rat brain DAGL and demonstrate that excessive 2-AG signaling contributes to a loss of inhibitory GABAergic constraint of VTA excitability following CNE.The mesocorticolimbic dopamine (DA) system provides a critical link between the brain regions that process cognitive information and those controlling motor behavior. Precise control of these ventral tegmental area (VTA) projections facilitates seeking rewarding stimuli, retreating from aversive stimuli, constraint of motivational state, and behavioral flexibility necessary for survival. GABAergic signaling provides robust inhibition that gates VTA DA cell excitability (1, 2), and loss of this inhibition leads to pathological dysregulation of mesocorticolimbic circuitry (3, 4).Endocannabinoids (eCBs) regulate DAergic activity through retrograde signaling from DA cell bodies onto presynaptic cannabinoid type 1 (CB1) receptors expressed on both inhibitory and excitatory inputs. Although both 2-arachidonoylglycerol (2-AG) and anandamide (AEA) function as endogenous CB1 agonists in the brain (57), these lipids exhibit distinct pharmacological profiles in vivo (8, 9) and mediate differential behavioral effects (10, 11). Endocannabinoids are produced and degraded on-demand, and the primary enzymes responsible for eCB degradation have been well-characterized using selective pharmacological tools that inactivate monoacylglycerol lipase (MAGL) or fatty acid amide hydrolase (FAAH) (1113). However, a complete evaluation of the influence of eCB signaling in the brain has been hampered by the lack of appropriate corresponding tools for selectively inactivating on-demand eCB biosynthesis.Substantial evidence implicates eCB signaling in the etiology of nicotine addiction, and recent work demonstrates that chronic nicotine exposure (CNE) selectively enhances nicotine-induced increases in VTA 2-AG formation (14). The present study investigated the possible contribution of this effect to aberrant VTA DA cell excitation present following CNE (15). We find that sensitized nicotine-induced 2-AG release (14) strongly correlates with a loss of nicotine-induced GABA release, which may contribute to impaired inhibitory constraint of VTA DA cell excitation following CNE. To test this hypothesis, we characterized a series of selective inhibitors of 2-AG biosynthesis by diacylglycerol lipase α and β (DAGLα and DAGLβ; hereafter referred to as DAGL) (1618) and 2-AG degradation by α/β-hydrolase domain 6 (ABHD6) and MAGL (11, 12, 19), and used these compounds to investigate the functional impact of enhanced 2-AG recruitment on GABAergic signaling at VTA synapses and nicotine self-administration.  相似文献   
993.
BACKGROUND: Cardiovascular risk factor research has recently broadened its focus based on new data indicating the benefits of low risk, i.e. favorable levels of all major risk factors. The aims of this study were to assess further the relation of low risk to coronary heart disease risk, and implications for prevention. DESIGN: We conducted a prospective population-based Italian study, of 7438 men and 13 009 women aged 35-69 years, with a mean follow-up of 10.4 years and validated first coronary events. METHODS: Baseline coronary heart disease risk was classified into three categories: low risk; unfavorable but not high risk; and high risk. To analyze the relation of these risk profiles to coronary heart disease incidence, age-adjusted, sex-averaged coronary heart disease incidence was calculated for persons free of coronary heart disease and stroke, stratified as baseline low risk, unfavorable but not high risk or high risk. To assess the independent relationship of individual risk factors to coronary heart disease incidence, multivariate proportional hazards models were computed for combinations of risk factors. RESULTS: Only 2.7% of participants met low risk criteria; 81.4% were high risk. Age-adjusted coronary heart disease incidence for the whole cohort was 37.1 out of 10000 person-years (men 59.0; women 15.3). No coronary heart disease events occurred in low-risk men, only two in low-risk women. For women and men who were not high risk, the age-sex standardized coronary heart disease rate was 62% lower than for high-risk participants. Blood pressure, need for antihypertensive medication, smoking, hyperglycemia, diabetes, total and high-density lipoprotein cholesterol were independently related to coronary heart disease risk. CONCLUSIONS: Favorable levels of all modifiable readily measured risk factors - rare among Italian adults - assure minimal coronary heart disease risk. Population-wide prevention is needed, especially improved lifestyles, to increase the proportion of the population at low risk.  相似文献   
994.
In US men, the incidence of anal cancer, the primary cause of which is human papillomavirus (HPV) infection, has increased almost 3-fold in 3 decades; however, little is known about the epidemiology of anal HPV infection, especially in heterosexual men. In 2 US cities, behavioral data and anal biological specimens were collected from 253 men who acknowledged having engaged in sexual intercourse with a woman during the preceding year. On the basis of DNA analysis, overall prevalence of anal HPV infection was found to be 24.8% in 222 men who acknowledged having had no prior sexual intercourse with men. Of the men with anal HPV infection, 33.3% had an oncogenic HPV type. Risk factors independently associated with anal HPV were lifetime number of female sex partners and frequency of sex with females during the preceding month. These results suggest that anal HPV infection may be common in heterosexual men.  相似文献   
995.
BACKGROUND/AIMS: The objective of the present study was to measure gastric emptying time of solids and semisolids in dyspeptic individuals with cholecystolithiasis before and 6 months after cholecystectomy in order to determine whether cholecystectomy interferes with gastric emptying. METHODOLOGY: A prospective, self-pairing study was conducted on 29 patients selected according to appropriate inclusion and exclusion criteria. Gastric emptying time of solids and semisolids was determined before and six months after laparoscopic cholecystectomy by the 13C-octanoic acid and 13C-acetate breath tests, respectively. The samples were analyzed by infrared spectrometry. The gastric retention time (lag phase) and gastric emptying half-time of solid and semisolid were determined and the results obtained before and after surgery were compared in the same patient. In addition, the effects of surgery on dyspeptic symptoms were assessed. RESULTS: No significant differences (p>0.05) in gastric retention time and gastric emptying half-time of solid and semisolid test meals were observed before and after cholecystectomy. Dyspeptic symptoms (pain, upper abdominal gases, early satiety, nausea and vomiting) improved after surgery. CONCLUSIONS: Laparoscopic cholecystectomy does not interfere with the gastric emptying time of solids or semisolids in dyspeptic individuals with cholecystolithiasis.  相似文献   
996.

Introduction

The aim of this study was to analyse the incidence, treatment and evolution of infections in children treated with ECMO.

Methods

A retrospective study based on a prospective database was performed. Children under the age of 18 years treated with ECMO from September 2006 to November 2015 were included. The patients’ clinical characteristics were collected, together with ECMO technique, cultures and treatment of infection.

Results

One hundred patients with a median age of 11 months were analysed. Heart disease was diagnosed in 94 patients. An infection was suspected and antibiotic treatment was initiated in 51 patients, although only 22 of them were microbiologically confirmed. The most common infection was sepsis (49%), followed by pneumonia (35.3%) and urinary tract infection (9.8%). There were no differences in haematological parameters and acute phase reactants between children with infection and those without. Children who died had a higher incidence of infection during ECMO (60.4%) than the survivors (40.3%), but the difference did not reach statistical significance (P = .07). The duration of admission in the PICU was 57 days in patients with infection vs 37 days in patients without infection but the difference was not statistically significant (P = .067).

Conclusions

Infection in children with ECMO is common. There are no specific infection parameters and less than half of the clinical infections are confirmed microbiologically. There was no statistically significant correlation between infection and mortality or duration of PICU stay.  相似文献   
997.
BACKGROUND: The place of virtual colonoscopy (VC) in patients with Crohn's disease (CD) requiring endoscopic follow-up after surgery is unknown. The authors compared findings from VC versus conventional colonoscopy (CC) for assessing the postoperative recurrence of CD. METHODS: Sixteen patients with ileocolonic anastomosis for CD were prospectively enrolled from January 2001 to January 2002. Recurrence was assessed by CC according to Rutgeerts et al. VC was performed with a computed tomography scanner, with images examined by three radiologists who were unaware of the endoscopic findings. RESULTS: CC showed perianastomotic recurrence in 15 of 16 patients. Perianastomotic narrowing or stenosis was detected by VC in 11 of these 15 patients. There were 11 true positive, 1 true negative, 0 false-positive, and 4 false-negative findings (73% sensitivity, 100% specificity, 100% positive predictive value, 20% negative predictive value, 75% accuracy). Among the eight patients showing a rigid stenosis of the anastomosis not allowing passage of the colonoscope, VC detected narrowing or stenosis in seven patients. CONCLUSIONS: The current findings suggest that although the widespread use of VC in CD is currently not indicated because of possible false-negative findings, this technique may represent an alternative to CC in noncompliant postsurgical patients with a rigid stenosis not allowing passage of the endoscope.  相似文献   
998.
Congenital ventricular diverticula are rare. Clinically, they may be asymptomatic or cause systemic embolization, heart failure, valvular regurgitation, ventricular rupture, ventricular arrhythmia, or sudden death. We report the case of a 56-year-old woman with sustained ventricular tachycardia, who, during investigation, was diagnosed with a diverticulum in the inferobasal portion of the left ventricle. The clinical characteristics and treatment of this rare disease are discussed.  相似文献   
999.
BACKGROUND: Since the sixties, when the optic fibers were reported, colonoscopy had emerged as the first line imaging investigation of the colon. AIM: To review the results of diagnostic and therapeutic colonoscopy at the Discipline of Coloproctology of the University of S?o Paulo Medical School, S?o Paulo, SP, Brazil, respecting the characteristics of an institution of medical education. METHODS: Retrospective analysis of basis related to 2,567 fibro colonoscopies between 1984 and 2002. The procedure was performed in hospitalized and in outpatients. The most common indications for colonoscopy were investigation of rectal bleeding and anemia (22.4%), change of bowel habit (14.76%), inflammatory bowel disease (8.65%) and carcinoma (7.25%). Bowel preparation with manitol was used by most of the patients. Sedation, when not contra-indicated, was administered. The most common combination was meperidine and benzodiazepine. All the exams were monitored with pulse oximeter. A normal colonoscopy to the point of maximum insertion was reported in 42.42% of procedures. The most common diagnosis was polyps (15.47%), followed by diverticular disease (12.86%). Inflammatory disease was recorded in 11.88% and carcinoma in 10.21%. Polypectomy was undertaken in 397 patients (2.21 polypectomy per patient with polyps). Colonoscopy was considered incomplete (when the colonoscope did not pass to the cecum or terminal ileum) in 181 (7.05%) cases. Perforation was reported in one patient who had a subestenosing retossigmoid tumor. In 0.42%, reasons for failing to complete the procedure included complication related to sedation, with no further prejudice for the patients. CONCLUSIONS: Colonoscopic examination of the entire colon remains the standard for visualization, biopsy and treatment of colonic affections. The incidence of complication of endoscopy of the large bowel is quite low, even in a school hospital.  相似文献   
1000.
OBJECTIVES: IgM memory B cells that are responsible for the protection against infections by encapsulated bacteria, require the spleen for their generation and/or survival. Since the association between inflammatory bowel disease and functional hyposplenism is well described, our aim was to verify whether IgM memory B cells mirror the reduced splenic function in Crohn's disease and ulcerative colitis patients. METHODS: Peripheral blood samples were obtained from 32 Crohn's disease and 29 ulcerative colitis patients, 33 healthy controls, and 27 splenectomized patients. Perendoscopic intestinal biopsies were also collected from 15 of 32 Crohn's disease patients, 14 of 29 ulcerative colitis patients and 13 of 33 control subjects. Counting of erythrocytes with membrane abnormalities (pitted red cells) was used as an indicator of splenic function and flow cytometry was performed to analyze both peripheral and mucosal B cells. RESULTS: Twelve of 32 Crohn's disease patients and 13 of 29 ulcerative colitis patients had pitted red cell values >4% and were considered to be hyposplenic. In inflammatory bowel disease patients circulating IgM memory B cells were significantly lower than in control subjects. We observed a significant inverse correlation between the frequency of circulating IgM memory B cell and the pitted red cell values in inflammatory bowel disease patients with hyposplenism. To exclude the possibility that the reduction of circulating IgM memory B cells reflected their recruitment in the inflamed bowel mucosa, lamina propria B-cell populations were also characterized. We found that the frequency of IgM memory B cells was similar in the blood and in the lamina propria of the same patient. CONCLUSIONS: Our findings show that peripheral IgM memory B cells are reduced in inflammatory bowel disease patients and this defect seems to be related to the impairment of splenic function.  相似文献   
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