HLA-DR antigen expression and lymphocyte subsets in transitional cell carcinoma of the urinary bladder. An immunohistological study on frozen sections

Lymphocyte subpopulations (B cells, CD4, CD8), interleukin-20 receptors (IL-2), monocytes/macrophages (Leu M₅), and HLA-DR antigen expression were studied immunohistochemically on frozen sections from 38 bladder cancer specimens. T cells predominated over B cells in all tumours. CD4-positive lymphocytes predominated over CD8 in the stroma (CD4/CD8: 1·35/1), while in epithelial tumour cells CD8 was the prominent subpopulation (CD8/CD4: 1·75/1). Aberrant HLA-DR expression was found in 21·05 per cent of bladder tumours. A strong correlation between CD4 and CD8 population densities and macrophages with the other subpopulations was noticed. In HLA-DR-positive tumours, there was no correlation of the percentage of positive cells with CD4- and CD8-positive lymphocyte populations. Various parameters including IL-2 receptors, B cells, CD8- and CD4-positive cells, and macrophages did not differ significantly between the groups of tumours expressing and not expressing HLA-DR antigen. There were no statistically significant differences in the population densities of B cells, CD8- or CD4-positive cells, IL-2 receptor, monocytes/macrophages, and HLA-DR antigen expression among various clinicopathological parameters, including growth pattern, histological grade and clinical stage or patient's age and sex. These findings suggest that in transitional cell carcinoma of the urinary bladder, HLA-DR antigen expression is independent of lymphocyte subpopulations. It is therefore possible that HLA-DR expression by tumour cells reflect the existence of separate HLA-DR-positive or HLA-DR-negative tumour clones.     

Partial scapholunate ligament injuries treated with arthroscopic debridement and thermal shrinkage

PURPOSE: To present the early results of arthroscopic debridement and thermal shrinkage using radiofrequency probes for partial (Geissler grades I and II) scapholunate (SL) interosseous ligament injuries of the wrist. METHODS: Sixteen patients with a mean age of 34 years (range, 18-54 y) presenting with chronic dorsoradial wrist pain unresponsive to initial conservative treatment for a mean period of 12 weeks were included in this study. No patient showed radiologic signs of static dissociation (SL interval, <3.5 mm; mean SL angle, 49 degrees ) before surgery. Diagnostic arthroscopy showed a partial SL tear in 14 patients and redundancy of the ligament in 2. Partial SL tears involved the membranous (proximal) and volar part of the ligament. All lesions were debrided and treated with thermal shrinkage using a bipolar radiofrequency probe. RESULTS: The mean follow-up period was 19 months (range, 9-34 mo). Fourteen patients experienced substantial pain relief whereas in 2 the pain remained unchanged. Eight patients were completely pain free. The mean flexion-extension arc was 142 degrees and the mean grip strength was 78% that of the unaffected side. No patient showed radiologic signs of arthritis or static or dynamic instability after surgery (SL interval remained <3.5 mm; mean SL angle, 53 degrees ). Based on the modified Mayo wrist score there were 8 excellent, 6 good, 1 fair, and 1 poor result. CONCLUSIONS: Partial SL ligament tears can be a source of radial-sided wrist pain. Scapholunate ligament debridement and thermal shrinkage effectively provided pain relief for most of the patients treated. Stability was maintained radiographically. No complications were noted from the use of radiofrequency probes. These reasonably favorable short-term results should be viewed cautiously. A longer follow-up study is necessary to determine the ultimate efficacy of this procedure.     

Deterministic nonlinear characteristics of in vivo blood flow velocity and arteriolar diameter fluctuations

We have performed a nonlinear analysis of fluctuations in red cell velocity and arteriolar calibre in the mesenteric bed of the anaesthetized rat. Measurements were obtained under control conditions and during local superfusion with NG-nitro-L-arginine (L-NNA, 30 microM) and tetrabutylammonium (TBA, 0.1 mM), which suppress NO synthesis and block Ca2+ activated K+ channels (KCa), respectively. Time series were analysed by calculating correlation dimensions and largest Lyapunov exponents. Both statistics were higher for red cell velocity than diameter fluctuations, thereby potentially differentiating between global and local mechanisms that regulate microvascular flow. Evidence for underlying nonlinear structure was provided by analysis of surrogate time series generated from the experimental data following randomization of Fourier phase. Complexity indices characterizing time series under control conditions were in general higher than those derived from data obtained during superfusion with L-NNA and TBA.     

Contrast echocardiography improves the diagnostic yield of transthoracic studies performed in the intensive care setting by novice sonographers.

BACKGROUND: Bedside portable echocardiography in the intensive care department (ICU) is technically difficult, but crucial for directing patient care. Prior studies have shown contrast echocardiography (CE) in the ICU clarifies left ventricular wall motion when performed by experienced sonographers (ESO). However, in most hospitals, ESO are unavailable around the clock, and less experienced cardiovascular fellows or trainees may be asked to perform these examinations. METHODS: Transthoracic echocardiograms were retrospectively evaluated by level III trained echocardiographers for 213 patients in the ICU. Most were performed to assess left ventricular function (65% or 139 of 213) and were scanned by cardiology fellows (70% or 149 of 213) with less than 3 months echocardiography experience. Contrast agent was used in 29% (62 of 213) of all patients. RESULTS: The conversion of suboptimal or diagnostically inadequate apical 4- and 2-chamber views to diagnostically adequate with contrast was statistically significant when performed by both cardiology fellows and ESO (Fischer exact test, P < .0002). CONCLUSIONS: CE is effective in improving the diagnostic yield of transthoracic echocardiographic ICU studies performed by both novice sonographers and ESO. Using cardiology fellows to perform CE in this setting can be appropriate, particularly in after-hour situations, when ESO are not always available and the clinical question is left ventricular function. Results also suggest cardiology fellows can easily learn CE.     

Modelling distractor devaluation (DD) and its neurophysiological correlates

A series of recent studies have shown that selective attention can influence the emotional value of both selected as well as ignored items. Specifically, ignored items (distractors) were consistently rated less positively in emotional evaluations, following attentional selection, relative to (typically) simultaneously presented items (targets). Furthermore, a known electrophysiological index of attentional selectivity (N2pc) was shown to correlate with the magnitude of the observed ‘distractor devaluation’ (DD). A neural model is presented here to account for these findings by means of a plausible mechanism linking attentional processes to emotional evaluations. This mechanism relies on the transformation of attentional inhibition of the distractor into a reduction of the value of that distractor. The model is successful in reproducing the existent behavioural results as well as the observed link between the magnitude of the attentional N2pc and the magnitude of DD. Moreover, the model proposes a series of testable hypotheses as well as specific predictions that call for further experimental investigation.     

The effect of the mode of delivery on the maternal-neonatal erythrocyte membrane acetylcholinesterase activity

Free radical production and high catecholamine levels are implicated with the modulation of acetylcholinesterase (AChE) activity.ObjectiveTo investigate the effect of the mode of delivery on maternal–neonatal erythrocyte membrane AChE activity.Subjects and methodsSome women with normal pregnancy (N = 30) were divided into two groups: group A (N = 16) with normal labour and vaginal delivery and group B (N = 14) with scheduled Cesarean section, twenty non-pregnant women were the controls. Blood was obtained from controls and from mothers pre- vs post-delivery as well as from the umbilical cord (CB). Total antioxidant status (TAS), membrane AChE activities and catecholamine blood levels were measured with a commercial kit, spectrophotometrically and HPLC methods, respectively.ResultsTAS and catecholamine levels as well as membrane AChE activities were similar in the two groups of mothers pre-delivery and in controls. TAS levels were reduced whereas AChE activities and catecholamine levels were increased post-delivery in mothers of group A and unaltered in group B at the same times of study. AChE activity was similarly lower in the CB of neonates than those of their mothers pre-delivery.ConclusionsDuring a normal delivery process, the low TAS, the increased levels of catecholamines and the increased AChE activity, post-delivery, may be due to the increased stress due to the participation of uterus and skeletal muscles as during endurance exercise. The low AChE activity in newborns may be related to perinatal immaturity.     

Dramatic reduction of erythrocyte glucose-6-phosphate dehydrogenase activity in athletes participating in the ultradistance foot race "Spartathlon"

OBJECTIVE: To investigate the effect of a long-distance endurance exercise "Spartathlon" on erythrocyte glucose-6-phosphate dehydrogenase (G(6)PD) activity. MATERIAL AND METHODS: The study comprised 15 male runners, median age 36.5 years. Blood samples were obtained in the 15 min before the race and again within 15 min after the end of the race. Erythrocyte glutathione (GSH and GSSG) and plasma malonyldialdehyde were measured with HPLC methods, and total antioxidant capacity (TAC), total hyperoxides and G(6)PD activity with commercial kits. Lipids, uric acid and total bilirubin were determined with a clinical chemistry analyser. RESULTS: Total hyperoxides were found statistically reduced, whereas total bilirubin was measured elevated post-race. Interestingly, GSSG levels were found increased (167.3+/-12.0 versus 219.5+/-20.3 micromol/L; p<0.005) as well as GSSG/GSH ratio (16.0+/-1.3 versus 20.60+/-1.65; p<0.05) post-race. In contrast, G(6)PD activity was found remarkably decreased (8.72+/-3.10 versus 3.8+/-2.5 U/g Hb; p<0.0001) pre versus post the event. CONCLUSION: Red blood cell G(6)PD activity in athletes may be reduced post-race as a consequence of the modulation of NADP/NADPH levels and elevation of the erythrocyte GSSG, and especially GSSG/GSH ratio, resulting in an impairment of the hexose monophosphate shunt.