St Bartholomew's Hospital

About: St Bartholomew's Hospital is a healthcare organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Cancer. The organization has 11054 authors who have published 13229 publications receiving 501102 citations. The organization is also known as: St. Bartholomew's Hospital & The Royal Hospital of St Bartholomew.

Characteristics of Single Aortic and Right Subclavian Baroreceptor Fiber Activity in Rabbits with Chronic Renal Hypertension

Abstract: Experimental renal hypertension was induced in rabbits by wrapping polyethylene around one kidney and removing the other. The impulse activity in single baroreceptor fibers of the aortic nerves to the aortic arch and the right subclavian areas was studied 7-19 weeks postoperatively during nonpulsatile perfusion of an isolated aortic arch preparation. The results were compared with those obtained in normal rabbits. Curves relating the impulse frequency to the aortic arch pressure were constructed. In rabbits with hypertension, the threshold pressure of the aortic baroreceptor fibers was increased from a normal value of 52.5 ± 5.5 to 106.5 ± 5.8 mm Hg, and the point of inflection was increased from 112.4 ± 6.2 to 163.4 ± 5.1 mm Hg. The sensitivity of the baroreceptors to changes in pressure was reduced from 1.19 ± 0.14 to 0.64 ± 0.06 impulses/sec mm Hg-1. Similar results were obtained for the right subclavian area. Hysteresis, as indicated by the separation of the curves produced by first increasing and then reducing the aortic pressure, was more evident in rabbits with hypertension than in normal rabbits. The changes in baroreceptor activity in rabbits with hypertension were associated with alterations in the mechanical properties of the arterial walls, which were demonstrated by the pressure-volume curves. Also, there were demonstrable histological lesions of the arterial walls and the receptors in rabbits with hypertension.

Long-term outcome among men with conservatively treated localised prostate cancer.

Abstract: Optimal management of clinically localised prostate cancer presents unique challenges, because of its highly variable and often indolent natural history. There is an urgent need to predict more accurately its natural history, in order to avoid unnecessary treatment. Medical records of men diagnosed with clinically localised prostate cancer, in the UK, between 1990 and 1996 were reviewed to identify those who were conservatively treated, under age 76 years at the time of pathological diagnosis and had a baseline prostate-specific antigen (PSA) measurement. Diagnostic biopsy specimens were centrally reviewed to assign primary and secondary Gleason grades. The primary end point was death from prostate cancer and multivariate models were constructed to determine its best predictors. A total of 2333 eligible patients were identified. The most important prognostic factors were Gleason score and baseline PSA level. These factors were largely independent and together, contributed substantially more predictive power than either one alone. Clinical stage and extent of disease determined, either from needle biopsy or transurethral resection of the prostate (TURP) chips, provided some additional prognostic information. In conclusion, a model using Gleason score and PSA level identified three subgroups comprising 17, 50, and 33% of the cohort with a 10-year prostate cancer specific mortality of 30%, respectively. This classification is a substantial improvement on previous ones using only Gleason score, but better markers are needed to predict survival more accurately in the intermediate group of patients.

Dynamic MR imaging compared with evacuation proctography when evaluating anorectal configuration and pelvic floor movement.

Abstract: The aim of this study was to determine the agreement between measurements of the anorectal configuration made with dynamic MR imaging and with evacuation proctography.Ten women with constipation were examined sequentially using both standard evacuation proctography and dynamic MR imaging. Correlation and agreement between standard measurements of anorectal configuration at rest and during straining or evacuation of the rectum were evaluated.Significant correlation existed for anorectal junction descent (r = .7, p = .023), change in the anorectal angle (r = .78, p = .008), the position of the rectal axis on straining (r = .62, p = .032), and rectocele depth (r = .82, p = .004). The mean of the measurement differences for anorectal junction descent as measured using the two techniques was -0.23 cm (SD, 1.40 cm). The mean of the measurement differences for change of the anorectal angle was +15.3 degrees (SD, 27.92 degrees).Standard measurements of anorectal configuration made using evacuation proctography an...

Mucinous carcinoma of the rectum.

Abstract: We have studied and compared 316 mucinous and 45 signet ring cell carcinomas of the rectum with 413 non-mucinous carcinomas. Mucinous carcinomas were subdivided according to the amount of mucus which was gauged subjectively as either more or less than 75% of the tumour volume. Five year survivals for non-mucinous, mucinous (less than 75%), mucinous (greater than 75%) and signet ring cell carcinoma were 62%, 60%, 53% and 13%. Mucinous carcinomas (less than 75%) were relatively well differentiated and showed an age distribution identical to their non-mucinous counterparts, but differed in their strong association with villous adenoma. Mucinous carcinomas (greater than 75%) were less well differentiated and, like signet ring cell carcinomas, occurred in younger patients and showed no special association with villous adenoma. Clinically important and independent predictive variables were found by the method of multivariate regression analysis to be number of lymph node metastases, extent of spread in continuity, character of invasive margin and peritumoural lymphocytic infiltration. After adjustment for these factors, typing of rectal cancer as mucinous, non-mucinous and signet ring cell gave no additional, clinically useful prognostic information.

Endothelin-1 stimulates the biosynthesis of tumour necrosis factor in macrophages : et-receptors, signal transduction and inhibition by dexamethasone

Abstract: Endothelin-1 (ET-1) enhances the biosynthesis of interleukin-6 (IL-6) in endothelial cells and bone marrow-derived stromal cells of the rat. This study investigates (i) whether ET-1 stimulates the formation of tumour necrosis factor alpha (TNF alpha) or interferon-gamma (IFN gamma) in cultured macrophages or in the anaesthetized rat. Incubation of J774.2 macrophages with ET-1 (0.001-1 microM) caused a concentration- and time-dependent increase in the concentration of TNF alpha, but not of IFN gamma, in the culture medium. The increase in TNF alpha caused by stimulation of J774.2 macrophages was abolished by pretreatment of cells with (i) the protein synthesis inhibitor cycloheximide, (ii) with the selective ETA-receptor antagonists BQ-123 or BQ-485 (but not the selective ETB-receptor antagonist BQ-788), (iii) the tyrosine kinase inhibitors genistein or tyrphostin AG126, or (iv) with the glucocorticoid, dexamethasone. The inhibition by dexamethasone of the formation of TNF alpha by cells activated with ET-1 is not due to the formation of lipocortin-1 (LC1), as it was not reduced by a monoclonal antibody against LC1. Systemic administration (i.v.) of ET-1 (1 nmol.kg-1) to anaesthetized rats caused a rapid and sustained (maximum: 45 min; return to baseline: within 180 min) rise in the plasma levels of TNF alpha. This is the first demonstration that ET-1 can release proinflammatory cytokines in vitro and in vivo. The generation of TNF alpha caused by ET-1 involves (in sequence) the (i) activation of ETA-receptors, (ii) activation of tyrosine kinase resulting in the phosphorylation of intracellular proteins, (iii) the activation of, hitherto, unknown transcription factors, finally resulting in (iv) transcription and translation of the TNF alpha gene. The generation of TNF alpha by cells activated with ET-1 points to a pro-inflammatory role of ET-1 in diseases associated with local (e.g. atherosclerosis, heart failure) or systemic inflammation (circulatory shock), which are associated with high ET-1 plasma levels.