The thymus as primary site for antigen-specific T suppressor cells in neonatally induced tolerance to bovine serum albumin

The ontogeny of antigen-specific T suppressor cells in thymus and spleen was analyzed in CBA/Ca mice which were rendered tolerant as neonates by subimmunogenic doses of bovine serum albumin (low-zone tolerance). Activity of T suppressor cells from those mice was assessed by an assay in which spleen cells from animals primed with fluorescein-conjugated human gamma globulin can be stimulated in vitro to produce IgG anti-fluorescein antibodies when cultured in the presence of fluorescein-conjugated bovine serum albumin. Carrier-specific T suppressor cells appear first in the thymus (day 10), and much later (day 30) in the spleen. The data are discussed in connection with the possible role of T suppressor cells during induction of tolerance in newborn mice.     

Activity of human erythrocyte gangliosides as a receptor to HVJ

Liposomes could bind and fuse efficiently to human erythrocytes in the presence of HVJ when they contained gangliosides isolated from human erythrocytes. Sialosylparagloboside, which has a terminal sequence of NeuAcα2?3Ga1β1?4GlcNac, has a much higher receptor activity to the virus than GD_1a, GD_1b, GT_1b, and GT_1a, all of which contain the terminal sequence of NeuAcα2?3Galβ1?3GalNAc or NeuAcα2?8NeuAcα2?3Galβ1?3GalNAc. The activity of sialosylparagloboside is comparable to that of glycophorin, a major sialoglycoprotein of human erythrocytes, when compared on the basis of the required amount (as sialic acid) of compounds. The high affinity of sialosylparagloboside to the viral HANA protein is also suggested by the finding that it showed high inhibitory activity against HVJ-mediated binding of glycophorin liposomes to erythrocytes. Sialosylparagloboside was also highly susceptible to the viral sialidase, the other biological function of HANA protein.     

Chemical Characterization of Macrophage Cytotoxicity Factor,Macrophage Migration Inhibitory Factor,T-Helper Cell-Replacing Factor and Colony-Stimulating Factor from Culture Supernatants of Concanavalin A-Stimulated Murine Spleen Cells

Supernatants from Concanavalin A-stimulated murine spleen cells were subjected to hydrophobic interaction chromatography on phenyl-Sepharose. Macrophage cytotoxicity factor (MCF), macrophage migration inhibitory factor (MIF), T-helper cell-replacing factor (TRF) and colony-stimulating factor (CSF) were bound at high ionic strength and were released stepwise at low ionic strength. CSF thus could be separated from MCF, MIF and TRF and the bulk of other proteins. Chromatography of pools containing MCF, MIF and TRF on Sephadex did not lead to a separation of the three activities which were all found in a molecular weight range of 25.000-55.000. Isoelectric focusing of these pools in pH range from 4 to 9 gave two peaks for MCF at pH 8.2 and 7.2, whereas MIF activity focused from pH 4.5 to 5.5. TRF activity was found in a single sharp peak at pH 5.3. The results demonstrate that the four biological activities can be distinguished on a chemical basis and are accessible for purification and chemical characterization.     

Direct visualization of membrane clustering and endocytosis of thyrotropin into cultured thyroid cells

We prepared a highly fluorescent conjugate of thyrotropin (TSH) which retains approximately 25% of the binding affinity of native TSH towards TSH receptor and approximately 25% of the potency of the native hormone in stimulating the accumulation of cAMP in thyroid cells. Using an image-intensified microscopy system, we observed that our fluorescent TSH bound specifically to diffusely distributed membrane receptors on live rat or bovine embryo thyroid cells grown in culture. At 37 degrees C the fluorescent hormone formed visible patches which were internalized and subsequently degraded. Hence, TSH, like other polypeptide hormones, is internalized by a process of receptor-mediated endocytosis. The addition of bivalent antibodies against the fluorophore rhodamine, to thyroid cells that were previously exposed to sub-optimal concentrations of rhodamine TSH, elicited maximal stimulation of the thyroid adenyl cyclase. Monovalent Fab' fragments did not enhance the response of rhodamine TSH. Therefore we conclude that enhanced surface clustering of TSH molecules increases their capacity to stimulate the adenyl cyclase of thyroid cells.     

固本益肠片联合复方谷氨酰胺和曲美布汀治疗肠易激综合征的临床研究

目的探讨固本益肠片联合复方谷氨酰胺和曲美布汀治疗肠易激综合征的临床疗效。方法收集2014年3月—2016年3月在上海市同仁医院接受治疗的肠易激综合征患者86例,随机分为对照组(43例)和治疗组(43例)。对照组口服复方谷氨酰胺颗粒,1袋/次,3次/d,同时口服马来酸曲美布汀片,0.1 g/次,3次/d。治疗组在对照组的基础上口服固本益肠片,4片/次,3次/d。两组患者均连续治疗4周。观察两组患者临床疗效,同时比较治疗前后两组患者肠道症状尺度表(BSS)评分、血浆生长抑素(SS)、血管活性肠肽(VIP)及胃动素(MTL)水平变化。结果治疗后,对照组和治疗组总有效率分别为81.14%和95.35%,两组总有效率比较差异具有统计学意义(P0.05)。治疗后,两组患者BBS总积分明显低于同组治疗前,同组治疗前后比较差异有统计学意义(P0.05);且与对照组治疗后相比,治疗组降低的更明显,两组比较差异具有统计学意义(P0.05)。治疗后,两组患者血浆SS、VIP和MTL水平均明显降低,同组治疗前后比较差异具有统计学意义(P0.05);且治疗组患者比对照组降低的更明显,两组比较差异具有统计学意义(P0.05)。结论固本益肠片联合复方谷氨酰胺和曲美布汀治疗肠易激综合征效果显著,可明显改善患者临床症状及生活质量,具有一定的临床推广应用价值。     

Admission Braden Skin Score Independently Predicts Mortality in Cardiac Intensive Care Patients

ObjectiveTo determine whether a low Braden skin score (BSS), reflecting increased risk for skin pressure injury, would predict lower survival in cardiac intensive care unit (CICU) patients after adjustment for illness severity and comorbidities.Patients and MethodsThis retrospective cohort study included consecutive unique adult patients admitted to a single tertiary care referral hospital CICU from January 1, 2007, through December 31, 2015, who had a BSS documented on CICU admission. The primary outcome was all-cause hospital mortality, using elastic net penalized logistic regression to determine predictors of hospital mortality. The secondary outcome was all-cause post-discharge mortality, using Cox proportional hazards models to determine predictors of post-discharge mortality.ResultsThe study included 9552 patients with a mean age of 67.4±15.2 years (3589 [37.6%] were females) and a hospital mortality rate of 8.3%. Admission BSS was inversely associated with hospital mortality (unadjusted odds ratio, 0.70; 95% CI, 0.68-0.72; P<.001; area under the receiver operator curve, 0.80; 95% CI, 0.78-0.82), with increased short-term mortality as a function of decreasing admission BSS. After adjustment for illness severity and comorbidities using multivariable analysis, admission BSS remained inversely associated with hospital mortality (adjusted odds ratio, 0.88; 95% CI, 0.85-0.92; P<.001). Among hospital survivors, admission BSS was inversely associated with post-discharge mortality after adjustment for illness severity and comorbidities (adjusted hazard ratio, 0.89; 95% CI, 0.88-0. 90; P<.001).ConclusionThe admission BSS, a simple inexpensive bedside nursing assessment potentially reflecting frailty and overall illness acuity, was independently associated with hospital and post-discharge mortality when added to established multiparametric illness severity scores among contemporary CICU patients.     

Extraction of Evoked Potentials Based on Borel Spectral Measure for Less Trial Mixtures in Stable Distribution Environments

Stable process can better model the EEG noises found in the impact acceleration experiment. A new method for identifying the independent components of evoked potentials for less trial mixtures is proposed. The method is based on an estimate of the discrete Borel spectral measure for the characteristic function of an alpha stable random vector. Simulations demonstrate that the proposed method can identify independent components and the basis vectors of mixing matrix in the so-called less trial mixtures case of more sources.     

Cytotoxicity of drugs and diverse chemical agents to cell cultures

Two tissue culture methods and 5 cell lines were compared in measuring the values of cytotoxicity 50 per cent (CT₅₀) and CT₀ of 40 different drugs and 25 diverse chemical compounds. The CT₅₀ values obtained under each cell culture technique used did not show significant differences.There were marked differences in cytotoxicity and dose responses of the chemical compounds could be assigned to 3 categories, and the compounds tested were differentiated into 3 classes. The importance of the dose response to studies in viral chemotherapy is stressed, and the ability of CT₅₀ and CT₀ in other fields of biomedical research is discussed.