Esophageal epithelial response to gastroesophageal reflux

Exposure of the distal esophageal mucosa to acid gastric juice was quantitated by 24-hr pH monitoring in 100 individuals and was correlated with morphologic data derived from esophageal biopsies. The degree of acid exposure to the distal esophagus correlated directly with increases in both relative and absolute length of the subepithelial papillae and to relative basal zone hyperplasia. Both papillary length and basal zone hyperplasia decreased after antireflux surgery had reduced acid exposure to normal. Reflux in the recumbent position resulted in prolonged exposure of the mucosa to acid because of poor acid clearing from the esophagus. This caused longer papillae than did upright reflux, where there were more frequent reflux episodes, but with rapid acid clearance. The presence of a hiatal hernia was associated with longer papilae, lower DES pressure, increased reflux frequency, and prolonged recumbent acid clearance. Twenty-four hour pH monitoring correlated better with papillary length than did symptoms or other clinical measures of gastroesophageal reflux.     

Platelet alpha-granule and plasma membrane share two new components: CD9 and PECAM-1

CD9 (p24) and PECAM1 (CD31) antigens are well-defined components of the platelet plasma membrane. Both are integral glycoproteins (GPs) implicated in the adhesive and aggregative properties of human platelets. In the present report, we have investigated their subcellular localization using immunoelectron microscopy. The monospecificity of the two polyclonal antibodies used was confirmed by immunoblotting. On normal resting platelets, immunolabeling for CD9 and PECAM1 was found lining the plasma membrane and the luminal face of the open canalicular system. Some labeling was also consistently found on the alpha-granule limiting membrane. This was confirmed by double labeling experiments in which fibrinogen and von Willebrand factor (vWF) were used as alpha-granule markers. CD9 and PECAM-1 were found lining the membrane of the same granules that contained fibrinogen and vWF in their matrix. CD9 and PECAM-1 thus appear to have an intracellular distribution identical to GPIIb-IIIa, a major aggregation platelet receptor. To rule out a cross-reactivity of the two polyclonal antibodies with GPIIb/IIIa, we studied PECAM1 and CD9 expression on the platelets from a patient with type I Glanzmann's thrombasthenia whose platelets are devoid of GPIIb/IIIa. The same pattern of labeling was observed for both antigens as for normal platelets. Normal platelets were further observed after stimulation by agonists that either fail to induce (ADP) or induce granule secretion (thrombin). After treatment with ADP, platelets changed shape and centralized their granules; the plasma membrane immunolabeling remained unchanged; and gold particles were still found decorating the periphery of the centralized alpha- granules. After thrombin treatment, alpha-granules fused with the platelet membrane and secretion occurred. A significant increase of labeling was then observed on the platelet surface. From these results we conclude that the alpha-granule membrane contains two additional receptors in common with the plasma membrane. This suggests that alpha- granule membrane receptors may originate from a dual mechanism: direct targeting from the Golgi complex in megakaryocytes (for alpha-granule- specific receptors such as P-selectin) or by endocytosis from the plasma membrane (for proteins distributed in the two compartments).     

Analysis of exercise-induced R wave amplitude changes in detection of coronary artery disease in asymptomatic men with left bundle branch block

The exercise electrocardiograms of 44 asymptomatic men with acquired left bundle branch block were analyzed for changes in R wave amplitude. Results were correlated with findings on selective coronary angiography. There were two subgroups: 7 men with significant angiographic coronary artery disease (Group I) and 37 with normal coronary angiograms (Group II). Exercise induced an increase in R wave amplitude in all seven men with coronary artery disease but in only 10 of the 37 men without significant coronary artery disease. This criterion thus had a sensitivity of 100 percent but a poor specificity of 73 percent, a predictive value of 41 percent and an accuracy rate of 77 percent for the diagnosis of coronary artery disease. The greater the increase in R wave amplitude the greater was the likelihood of some degree of left ventricular dysfunction as measured by wall motion abnormalities and elevated left ventricular end-diastolic pressure. The increase in R wave amplitude with exercise appears to be a sensitive test in identifying coronary artery disease in asymptomatic men with acquired left bundle branch block.     

Influence of obesity indices, metabolic parameters and age on cardiac autonomic function in abdominally obese men

Heart rate variability (HRV) is affected by age, hyperglycemia and accumulation of body fat. This study compares the predictive value of four measurements of adiposity/obesity on HRV and investigates the specific role of age, metabolic contributors and degree/distribution of fat in HRV alterations. The sample consisted of 97 non-diabetic and non-medicated men with features of the metabolic syndrome (50 ± 8 years of age, body mass index [BMI] 31 ± 3 kg/m², waist circumference [WC] 107 ± 9 cm, triglycerides 2.3 ± 0.7 mmol/L, fasting glucose 6.0 ± 0.5 mmol/L, insulin 156 ± 71 pmol/L; mean ± SD). WC, BMI, percent body fat (% fat, from dual energy X-ray absorptiometry) and visceral adipose tissue volume (VAT, from computed tomography) were used as measures of adiposity/obesity. HRV measures were obtained from 24-h, day- and night-time segments of Holter recordings. BMI presented no independent association with HRV. Percentage fat was the strongest obesity index to be associated with HRV: 24-h pNN50, rMSSD, HF and daytime pNN50, rMSSD, HF and LF (?0.27 ≤ std β ≤ ?0.20, P < .05). VAT was associated with 24-h SDNN, LF (std β = ?0.25 and ?0.20, P < .05, respectively) and daytime SDNN (std β = ?0.24, P < .05) while WC was associated with nighttime SDNN and SDANN (std β = 0.22 and 0.32, P < .05). In addition, age, fasting glucose, 2-h oral glucose tolerance test and triglycerides presented independent association with HRV. Adiposity/obesity measurements seem to be differently associated with HRV. An approach considering the combination of age, obesity and glucose metabolism factors could be helpful in the global cardiovascular risk management in abdominally obese men.     

Effectiveness of a pedometer-based program using a socio-cognitive intervention on physical activity and quality of life in a setting of cardiac rehabilitation

Background

Physical activity contributes to improve health and quality of life. However, the prevalence of sedentary lifestyle is elevated after an acute coronary syndrome.

Methods

A randomized controlled trial was performed to evaluate the impact of a pedometer-based program associated with a socio-cognitive intervention on physical activity behaviour, cardiovascular risk factors, and quality of life during the year after an acute coronary syndrome event. During hospitalization, we randomized 32 patients to an experimental group and 33 patients to a usual care group. The experimental intervention included 6 consultations with a clinical nurse specialist during 12 months.

Results

Groups characteristics were comparable. At baseline, the percentage of participants considered in the active range category was similar between groups (31% vs 41%; P = 0.915). However, the proportion of participants who were still active was greater in the experimental group than in the usual care group at 6, 9, and 12 months follow-up (75% vs 41%; 68% vs 36%, and 83% vs 55%, respectively; P < 0.05). After 12 months, changes in overall quality of life and in health and the functioning scores were different between groups (interaction effects [groups by time] P = 0.048 and P = 0.036, respectively).

Conclusions

The use of a pedometer concomitantly with a socio-cognitive intervention improves adherence to physical activity and quality of life during the year after an acute coronary syndrome event. This finding is relevant because physical activity and quality of life are a great concern in preventive cardiology. These results support applying this innovative approach in cardiac rehabilitation programs.     

Epidemiological features and specificities of HCV infection: a hospital-based cohort study in a university medical center of Calabria region

The epidemiological status of HCV in Europe, and in particular in Mediterranean countries, is continuously evolving. The genotype distribution is related to improvement of healthcare conditions, expansion of intravenous drug use and immigration. We review and characterize the epidemiology of the distribution of HCV genotypes within Calabria, an area of Southern Italy. We focus on the pattern of distinct HCV genotype changes over the last 16 years; particularly subtype 1b and genotype 4. We collected data by evaluating a hospital-based cohort of chronic hepatitis C patients; in addition, we report an update including new patients enrolled during last eight months.