How important is the 'quality' of the cytotoxic T lymphocyte (CTL) response in protection against HIV infection?

Cytotoxic T lymphocyte (CTL) responses have been associated with protection from HIV-1 infection in people with a high degree of exposure to HIV and who show no serological evidence of HIV infection (HEPS, highly exposed persistently seronegative). However, it remains unclear how protective CTL responses could apparently develop in a minority of people, whilst the great majority of HIV-infected people make strong CTL responses yet progress to AIDS and death. In this paper we review the data which supports the hypothesis that the quality of the T-cell response, rather than its magnitude, may be an important factor that merits further investigation.     

Direct determination or estimated value of plasma ionized calcium : indications and limits

Calcium plays a fundamental role in many essential for life functions. Ionized calcium (Ca(++) ) represents free fraction and 50% of the total calcium in the plasma is accepted as its physiologically active form. On almost all laboratories, only total calcium is routinely measured, and ionized calcium concentration is calculated based on calcium, protein or albumin concentrations for many plasma sample or with others parameters like pH. Since 1935, the literature was abounted with "correction" formulae of varying degree of sophistication. Many laboratories routinely use correction formulae to either calculate an "adjusted" or "corrected" total calcium, or "ionized" fraction is calculated,but these determinations lack of accuracy or precision. Errors associated with the measurement of the other variables contribuate to the difficulty in producing a useful correction formulae. Direct measurement of ionized calcium by potentiometry is the method of choice for this assay. Improvements in ion selective electrodes (ISE) technology make possible the routine clinical measurement of Ca(++). However this technology implies several obligations for its use, particulary in blood ampling, storage and transport. In this review, characteristics of different available analysers are described. We think that Ca(++) should be systematically performed and not calculated in pathological situations where an possible alteration of the calcium metabolism is found especially in multiple myeloma in which paraprotein may bind calcium.     

TGFβ1基因对血管内皮细胞细胞外基质表达及与基质黏附的影响

了解TGFβ1基因对血管内皮细胞表达细胞外基质蛋白及与基质黏附力的影响。用DOTAP脂质体转染p MAMneo TGFβ1于原代培养的脐静脉内皮细胞,经G4 18筛选,TGFβ1表达经免疫荧光鉴定。Western blot确定 型胶原、纤黏连蛋白的表达,微管吸吮系统确定内皮细胞与基质的黏附力。结果表明生理情况下的内皮细胞能表达少量的TGFβ1及胶原、纤黏连蛋白。经G4 18筛选,外源性TGFβ1在血管内皮细胞中稳定表达,能显著提高胶原、纤黏连蛋白纤维的表达及细胞与基质的黏附。说明TGFβ1在血管组织工程中促进内皮细胞的黏附具有一定的应用价值。     

Coordinate-based versus structural approaches to brain image analysis

A basic issue in neurosciences is to look for possible relationships between brain architecture and cognitive models. The lack of architectural information in magnetic resonance images, however, has led the neuroimaging community to develop brain mapping strategies based on various coordinate systems without accurate architectural content. Therefore, the relationships between architectural and functional brain organizations are difficult to study when analyzing neuroimaging experiments. This paper advocates that the design of new brain image analysis methods inspired by the structural strategies often used in computer vision may provide better ways to address these relationships. The key point underlying this new framework is the conversion of the raw images into structural representations before analysis. These representations are made up of data-driven elementary features like activated clusters, cortical folds or fiber bundles. Two classes of methods are introduced. Inference of structural models via matching across a set of individuals is described first. This inference problem is illustrated by the group analysis of functional statistical parametric maps (SPMs). Then, the matching of new individual data with a priori known structural models is described, using the recognition of the cortical sulci as a prototypical example.     

冠脉内支架临床发展策略

冠脉内支架是临床上预防ＰＴＣＡ并发症的有效措施，但金属支架固有的血栓菜成原性和对血管壁组织的永久性刺激可导致院内心脏事件和再狭窄。为解决上述问题，作者提出，血管内支架联合靶向药物传输离子照射或基因治疗、基因修饰的内皮细胞的种植支架、吱物可吸收缓释药物支架材料研制为临床冠脉内支架开辟了广阔的发展前景。     

Production and characterization of antibody against fusarochromanone

Antibody against fusarochromanone (TDP‐1) was obtained from rabbits after immunization with TDP‐1 conjugated to bovine serum albumin (BSA). An indirect enzyme‐linked immunosorbent assay (ELISA) using TDP‐1‐ovalbumin conjugate as the antigen coated on to the microtiter plate was used for monitoring the antibody liter. For toxin detection, a direct competitive ELISA in which TDP‐1 was conjugated to horseradish peroxidase (HRP) was used. Competitive direct ELISA revealed that the antibody had about 5.6 and 4.5 times greater binding efficiency for monoacetyl fusarochromanone (TDP‐2) and diacetylated TDP‐1 than TDP‐1. The concentration causing 50% inhibition of binding of TDP‐1‐HRP to the antibody by TDP‐1, TDP‐2 and diacetyl‐TDP‐1 were 2.8, 0.5 and 0.62 ng/ml, respectively. For the analysis of fusarochromanones in wheat and barley, the toxins were first extracted from the commodities with 100% methanol. A small aliquot of the extract was dried, acetylated, diluted in buffer and then analyzed directly by ELISA. The overall recovery for fusarochromanone in the wheat and barley samples spiked with TDP‐1 in the concentration range of 20 to 500 ppb were found to be 97% and 103.4% with cv of 15% and 11.2% for barley and wheat, respectively.     

Differential Growth of IFN-beta-Engineered Tumor Cells in Nude and IFN Receptor-Null Mice.

The purpose of this study was to investigate the therapeutic potential of interferon-beta (IFN-beta) against tumors that resist its antiproliferative effects. Mouse fibrosarcoma cells (UV-2237m-P) and their counterparts, transfected with either IFN-beta cDNA (UV-2237m-IFN-beta) or its control vector (UV-2237m-neo), were used in the study. UV-2237m-IFN-beta cells, still expressing functional IFN receptors, were resistant to the antiproliferative effects of IFN-beta. UV-2237m-P and UV-2237m-neo cells produced progressive tumors in both nude and IFN receptor-null nude (IFNAR-/-nude) mice. In contrast, growth of UV-2237m-IFN-beta cells was significantly delayed in nude mice. UV-2237m-IFN-beta tumors from nude mice contained fewer microvessels, fewer proliferating cells, and more apoptotic cells than did UV-2237m-P and UV-2237m-neo tumors. They expressed high levels of inducible nitric oxide synthase (iNOS) and were densely infiltrated by macrophages. Incubation with macrophages from nude mice, but not those from IFNAR-/- nude mice or iNOS-null/nude mice, led to more significant killing of UV-2237m-IFN-beta cells than that of control cells, which was blocked by iNOS inhibitor N-methylarginine. Similarly, more UV-2237m-IFN-beta cells were killed when they were incubated with spleen lymphocytes from nude mice. These data indicate that IFN-beta can inhibit growth of IFN-beta-resistant tumors by T cell-independent host-mediated mechanisms, including the role of macrophages, natural killer (NK) cells, and iNOS activity.     

Characterization of the neurochemical content of neuronal populations of the lamina terminalis activated by acute hydromineral challenge

The lamina terminalis (LT) contains three main regions, namely the subfornical organ (SFO), the median preoptic nucleus (MnPO) and the vascular organ of the LT (OVLT). Although LT is recognized of paramount importance in the regulation of hydromineral homeostasis, identity of the neurocircuits interconnecting the SFO and OVLT to the MnPO is not known. Furthermore, the phenotype of neuronal populations activated during acute hydromineral challenge is not yet determined. By using the high cellular resolution of the in situ hybridization histochemistry (ISHH), we investigated whether a furosemide-induced fluid and electrolyte depletion might modify both putative GABAergic and glutamatergic systems within the LT. We show that acute furosemide treatment (4 h) significantly reduced the expression of GAD67 mRNA, the active holoenzyme predictive of GABA synthesis, within the SFO. A strong tendency toward a reduction of GAD67 signal was also observed in the OVLT and MnPO. The hydromineral challenge did not alter the expression of GAD65 and type 2 vesicular glutamate transporter (vGlut2) mRNA in all the structures of the LT. Furosemide treatment was associated with a reduction in the population of GAD67-containing neurons in the periphery of the SFO and dorsal part of the MnPO. Contrastingly, GAD65-containing cells were shown to be increased in the OVLT and no change was observed for the vGlut2-containing neurons in the whole LT. By combining ISHH with immunohistochemistry (Fos immunoreactivity), we report that furosemide-induced water and sodium depletion did essentially recruit a glutamatergic network throughout the LT, although GABAergic neurons were specifically activated in the ring of the SFO and in the OVLT. The MnPO, the region of the LT that is considered as being an integrative area for sensory inputs arising from the SFO and OVLT, showed exclusive activation of excitatory neuronal populations. Taken together these results suggest that acute water and Na(+) depletion diminish the efficacy of the GABAergic system and mainly activates excitatory neuronal pathways in the regions of the LT.     

In vitro effects of the antiallergy compound,CI-949, on interleukin-1 and 2 release,and on mitogen and alloantigen responsiveness

CI-949 (5-methoxy-3-(1-methylethoxy)-1-phenyl-N-1H-tetrazol-5-yl-1H-indole-2-carboxamide,l-arginine salt), an antiallergy compound was found to be a weak inhibitor of IL-1 release from LPS-stimulated murine peritoneal exudate cells and human peripheral blood leukocytes, with IC₅₀s of 186.2 and 267.9 M, respectively. CI-949 was also a poor inhibitor of release of IL-2 from Con A-stimulated rat spelenocytes (37% inhibition at 100 M). CI-949 did produce concentration-related inhibition of the response of human lymphocytes to PHA and Con A (IC₅₀s=44.7 and 21.5 M, respectively) as well as in the mixed lymphocyte reaction (MLR) (IC₅₀=16.8 M). The clinical significance of these latter findings is unknown at present.