Self-reported stress and subsequent hospital admissions as a result of hypertension,varicose veins and haemorrhoids

BACKGROUND: This study examines a cohort in which individuals of privileged socio-economic position report greater psychological stress. We have previously shown in this cohort that stress is unrelated to coronary heart disease as measured by hospital discharge diagnosis and cause-specific death. In contrast, stress and hospitalization for cardiovascular conditions not requiring mandatory admission were associated. We hypothesized that psychosocial factors, in particular reporting tendency, are the likely mediator of this association, and the present study considers this further. METHODS: A total of 5,596 men underwent a health screening during which they completed the Reeder Stress Inventory. Details of hospital admissions were retrieved from the Scottish Morbidity Records over a 21 year follow-up. Relationships between stress and admission were evaluated using proportional hazards regression. RESULTS: Compared with low stress, reported high stress was found to be associated with increased numbers of admissions for each of three most common cardiovascular causes of non-mandatory admission: adjusted hazard ratios were 3.43 for essential hypertension (95 per cent confidence interval (CI) 1.36-8.65), 1.91 for lower limb varicose veins (95 per cent CI 1.12-3.24), and 2.01 for haemorrhoids (95 per cent CI 1.16-3.51). Stress and blood pressure at baseline were not associated. CONCLUSION: The association between stress and admissions as a result of hypertension appears unlikely to be mediated by blood pressure. More likely is a mechanism based upon the reporting of symptoms, or the recording of discharge diagnoses. There is no obvious medical explanation for associations between stress and hospitalization as a result of varicose veins or haemorrhoids, and again it is likely that psychosocial factors provide the mechanism.     

Vesicle-associated proteins and quantal release at single active zones of amphibian (Bufo marinus) motor-nerve terminals.

A study was made to determine the disposition of vesicle-associated proteins (syntaxin, SV2, SNAP-25) and calcium channels with respect to the spatial extent of spontaneous and evoked quantal release within regions of amphibian motor-nerve terminal branches delineated by FM1-43 stained vesicle clusters (blobs). Discrete concentrations of vesicles revealed approximately 2 microm apart along the length of terminal branches through FM1-43 staining were identical in size and spacing to those identified along terminal branches with SV2 antibody (AbSV2). Fluorescent antibodies to syntaxin 1 (AbS), SNAP-25 (AbS25) and the calcium channel alpha1B subunit (Abalpha1B) were found in relatively high concentrations coincident with the AbSV2 blobs. Three extracellular recording electrodes were placed in the vicinity of individual FM1-43 blobs, and an algorithm was used to determine the spatial origin of miniature endplate potentials (MEPPs) and EPPs together with their relative amplitudes. MEPPs and EPPs originated throughout the region stained by FM1-43 but not elsewhere; amplitude-frequency distributions of MEPPs and EPPs were similar for all FM1-43 blobs with average coefficients of variation of no less than 0.28. A linear relationship existed between the size of an FM1-43 blob, measured as the integrated extent of FM1-43 staining of a blob, and the frequency of MEPPs as well as the probability of EPPs from the blob. There was a proximo-distal gradient in the size of FM1-43 blobs along the length of single terminal branches, suggesting a gradient in release probability along the branches. The frequency distribution of the distances between blobs was approximately Gaussian, whereas the frequency distribution of the size of blobs was highly skewed and was best fitted with a gamma distribution. It is concluded that there are correlations among the extent of labeling of SNAP-25, syntaxin and calcium channels at a release site, the store of vesicles to be found there, and the probability of spontaneous and evoked quantal release.     

Phenotypic stability of articular chondrocytes in vitro: the effects of culture models, bone morphogenetic protein 2, and serum supplementation.

Numerous in vitro culture models have been developed for the investigation of chondrocyte and cartilage biology. In this study, we investigated the stability of the chondrocytic phenotype in monolayer, aggregate, pellet, and explant culture models and assessed the effects of recombinant human bone morphogenetic protein 2 (rhBMP-2) and serum supplementation on the phenotype in each model. Phenotypic effects were assessed by analyses of procollagen type II, aggrecan, (V + C)- fibronectin, and procollagen type I messenger RNA expression. In monolayer cultures, we noted a characteristic loss of procollagen type II and induction of procollagen type I expression. The aggregate and pellet culture models supported matrix protein gene expression profiles more reflective of in vivo levels. In explant cultures, expression of matrix protein genes was consistently depressed. Treatment with rhBMP-2 significantly increased the expression of procollagen type II and aggrecan in monolayer cultures; however, other models showed comparatively little response. Similarly, serum supplementation significantly down-regulated procollagen type II and aggrecan expression in monolayer cultures but had less effect on gene expression in the other models. Serum supplementation increased procollagen type I expression in monolayer and aggregate cultures. These results suggest that the influence of exogenous BMP-2 and serum on expression of chondrocyte-specific matrix protein genes is influenced by aspects of substrate attachments, cellular morphology, and/or cytoskeletal organization. Finally, the analyses of fibronectin expression suggest that V and C region alternative splicing in chondrocytes is linked to the establishment of a three-dimensional multicellular complex.     

Relative bioavailability of almitrine bismesylate in humans

Bioavailability and bioequivalency studies of almitrine bismesylate from U.S. manufactured film coated, waxed, 50 mg tablets were compared in 34 normal healthy volunteers to 50 mg European film coated, waxed and unwaxed, tablets and a 0.5 per cent (w/v) oral reference solution of almitrine bismesylate in d,l malic acid. The U.S. manufactured formulations were 85.88 and 87.85 per cent of the calculated mean area under the individual concentration-time curve for almitrine bismesylate reference solution compared to 88.40 and 88.86 per cent for the waxed and unwaxed film coated European tablets, respectively. The mean peak plasma concentrations for the U.S. formulations were 176.3 ng ml-1 and 180.1 ng ml-1 compared to 196.3 and 200.1 ng ml-1 for the waxed and unwaxed European formulations, respectively. Mean time to peak plasma concentrations for the two U.S. formulations and the waxed and unwaxed European formulations were 3.22, 3.33, 3.06, and 3.26 h, respectively. In addition, the oral reference solution yielded a mean peak plasma concentration of 222.8 ng ml-1 and a mean time to peak plasma concentration of 2.68 h. Analysis of variance and multiple range comparisons (p less than 0.05) indicated that the tablet formulations were bioequivalent. The results of this study show that the U.S. formulated almitrine bismesylate tablets exceed 85 per cent relative bioavailability with respect to the oral reference solution and are bioequivalent compared to the marketed standard European tablet formulations.     

The effects of diflunisal on bleeding time and platelet aggregation in a multidose study

Diflunisal, a potent nonsteroidal anti-inflammatory agent, has been confirmed as an effective analgesic in oral surgery. It is generally stated that there is only slight impairment of coagulation at the recommended dosage of diflunisal; however, only a few multidose studies have been conducted, most being single dose studies. This report is of a multidose study of the effects of diflunisal on coagulation in 15 oral surgery patients, being the first such study reported. The results showed that the bleeding time was increased in 53% of the group, but in no case did the increase exceed the upper limit of normal. Additionally, platelet aggregation studies were affected in 38% of patients with increased bleeding time. The overall results substantiate the safety of diflunisal in relation to effect on coagulation, and are directly applicable to postoperative use in oral surgery.