Tumor necrosis factor alpha-induced endothelial tissue factor is located on the cell surface rather than in the subendothelial matrix

Because there is no consensus regarding the precise distribution of induced endothelial tissue factor (TF), we studied TF activity in and on tumor necrosis factor alpha-stimulated cultured human umbilical vein endothelial cells (ECs) and their underlying matrix. TF was mainly expressed on the cell surface. Only small traces were found on the apical surface suggesting that TF is predominantly located on the basolateral side of the cell membrane. The presence of TF on the cell surface was confirmed by flow cytometry. Subendothelial TF activity appeared to be dependent upon the procedure used to remove the stimulated EC monolayer. Whereas ammonium hydroxide or hypotonic lysis resulted in relatively high levels of matrix-associated TF, virtually no TF was found on the matrix after mild enzymatic detachment of stimulated ECs. Cell removal with EDTA resulted in intermediate levels of matrix-associated TF. Neither the enzymatic treatment nor EDTA degraded or removed this TF activity. Similar patterns were observed for matrix-associated TF antigen and EC surface markers. Electron microscopic analysis showed cell fragments on the matrix after monolayer lysis. The findings strongly suggest that induced endothelial TF associated with the subendothelial matrix actually represents TF on EC remnants.     

Psychiatric symptoms and problem behaviours in people with intellectual disabilities

Background Previous studies have suggested different patterns of associations between psychiatric symptoms and problem behaviours in people with intellectual disabilities (ID). The aim of this study was to investigate which problem behaviours are associated with specific psychiatric symptoms and the relative strength of these specific associations. Method A cross sectional survey using the Psychiatric Assessment Schedule for Adults with Developmental Disabilities Checklist and the Disability Assessment Schedule was carried out in a sample of 214 adults with ID. Results Self‐injurious and, to a lesser extent, aggressive problem behaviours were most associated with affective type symptoms. Screaming and destructive behaviours tended to be more associated with autism‐related social impairment rather than conventional psychiatric symptoms. Conclusions This study gives further evidence of associations between psychiatric symptoms and specific problem behaviours in people with ID. It may be particularly useful to consider the diagnosis of affective disorders if a person with ID shows self‐injurious or aggressive behaviours.     

Altered levels of PP2A regulatory B/PR55 isoforms indicate role in neuronal differentiation

The ubiquitously expressed serine/threonine-specific protein phosphatase 2A (PP2A) is prominent in brain where it serves a wide range of functions under both physiological and pathological conditions. PP2A holoenzymes are composed of a catalytic subunit and a tightly complexed scaffolding subunit. This core enzyme associates with regulatory subunits of the B/PR55, B'/PR56/PR61, B'/PR72 and B'/PR93/PR110 families. We previously determined distribution and expression levels of the four members of the B/PR55 family in brain, as dysregulation of this subunit family has been specifically implicated in neurodegenerative disorders including Alzheimer's disease. In the present study, we used cell lines widely used in neuroscience research to determine levels of the four PR55 isoforms by qRT-PCR under different experimental conditions. We show that PR55alpha mRNA levels are highest in both HEK293 cells and SH-SY5Y neuroblastoma cells whereas PR55beta levels are lowest. Stepwise neuronal differentiation of SH-SY5Y cells causes the selective upregulation of PR55beta, and to some extent PR55gamma and PR55delta, but not PR55alpha mRNAs. In agreement with the qRT-PCR analysis, neuronal differentiation does not alter PR55alpha protein levels, whereas interestingly, PR55beta and PR55gamma protein levels are reduced when compared to undifferentiated cells. Our data point at specific roles for distinct regulatory B/PR55 subunits of PP2A in neuron-like cells with PR55alpha being the major isoform.     

Transmission of IgA to the rabbit foetus and the suckling rat

The transmission of purified preparations of rabbit and human colostral IgA globulin were studied in the rabbit across the yolk-sac splanchnopleur and in the young rat across the gut. Little or no IgA was transferred in either species.     

Concentrations of serum HVA and gonadal hormones in healthy first-degree relatives of schizophrenic patients

应用高压液相和放免分析法测定精神分裂症病人一级健康亲属和正常对照者的血清高香草酸（ＨＶＡ）、ＦＳＨ、ＬＨ和睾酮（ＴＳ）浓度。其结果显示，一级亲属总的（男和女）血清ＨＶＡ浓度明显高于正常对照者，血清ＦＳＨ、ＬＨ和ＴＳ浓度也趋于增高。提示，对精神分裂症疾病发生学ＨＶＡ和性激素有家族影响的趋势。