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91.
Osteopontin (OPN) is a macrophage chemotactic and adhesion molecule that acts to promote macrophage infiltration in rat anti-glomerular basement membrane (GBM) glomerulonephritis. The present study investigated the role of interleukin-1 (IL-1) in the up-regulation of renal OPN expression in this disease model. Accelerated anti-GBM glomerulonephritis was induced in groups of six rats. Animals were treated by a constant infusion of the IL-1 receptor antagonist or saline (control) over days -1 to 14 (induction phase) or days 7 to 21 (established disease). In normal rat kidney, OPN was expressed in a few tubules (<5%) and absent from glomeruli. During the development of rat anti-GBM disease (days 7 to 21), there was substantial up-regulation of OPN mRNA and protein expression in glomeruli (>5 cells per glomerular cross-section) and tubular epithelial cells (50-75% OPN-positive). Up-regulation of OPN expression was associated with macrophage accumulation within the kidney, severe proteinuria, loss of renal function, and severe histological damage including glomerular crescentic formation and tubulointerstitial fibrosis. In contrast, IL-1 receptor antagonist treatment of either the induction phase of disease or established disease significantly reduced OPN mRNA and protein expression in glomeruli (/75-85%, P < 0.001) and tubules (/45-60%, P < 0.001). The reduction in OPN expression was associated with significant inhibition of macrophage accumulation and progressive renal injury. In vitro, the addition of IL-1 to the normal rat tubular epithelial cell line NRK52E up-regulated OPN mRNA and protein levels, an effect that was dose-dependent and inhibited by the addition of IL-1 receptor antagonist, thus demonstrating that IL-1 can act directly to up-regulate renal OPN expression. In conclusion, this study provides in vivo and in vitro evidence that IL-1 up-regulates OPN expression in experimental kidney disease and support for the argument that inhibition of OPN expression is one mechanism by which IL-1 receptor antagonist treatment suppresses macrophage-mediated renal injury.  相似文献   
92.
Leukocyte adhesion to vascular endothelial cells is an essential step in the development of inflammatory diseases. We have searched for inhibitors of leukocyte-endothelial cell adhesion that could be used as anti-inflammatory drugs and found that bruceine B (0.2 g/ml; 0.44 M) inhibited human neutrophil or T cell adhesion to tumor necrosis factor- (TNF) stimulated human umbilical vein endothelial cells (HUVEC). The inhibition of neutrophil adhesion to TNF-stimulated HUVEC by bruceine B was not derived from cytotoxic effects, as determined by measurement of the level of lactate dehydrogenase (LDH) activity in conditioned medium. The effect of bruceine B on neutrophil adhesion to HUVEC was not seen when the neutrophils were preincubated with bruceine B. However, inhibitory effects were evident when the HUVEC were preincubated with bruceine B. Bruceine B also inhibited neutrophil adhesion to lipopolysaccharide-stimulated HUVEC and T cell adhesion to TNF-stimulated HUVEC. These findings suggest that bruceine B may have anti-inflammatory activity.  相似文献   
93.
The sequence is presented of RNA-5 of Echinochloa hoja blanca tenuivirus, a second tenuivirus associated with rice cultivation in Latin America (after rice hoja blanca virus). The RNA is 1334 nucleotides long and contains in the complementary sense RNA a single long open reading frame. The deduced amino acid sequence of this open reading frame shows that it encodes a highly basic and hydrophilic 44 kD protein (pc5) with about 50% similarity to the pc5 protein of maize stripe virus (MStV). This and other features of the RNA are discussed.The GenBank accession number of the sequence reported in this paper is L47430.  相似文献   
94.
95.
An experiment on rat undernutrition through seven generations was performed in order to see: (1) whether the nutritional stress on growth increases from one generation to the next, and (2) if an equilibrium point (AFP) in which the RFI--the amount of food intake (mg) per gram of body weight--reached is the same in both control and undernourished animals. The RFI values were calculated for each generation, between the 30th and 100th days of age. A moderate undernutrition was applied to the seven generations (F1 to F7) following the parental (P) one, which acted as controls. Undernourishment was made from conception to the end of the experiment (100 days old). The RFI values diminished with the age increment and increased through generations. There was, however, a clear AFP of 75.9 +/- 3.5 mg/g at 100 days of age in males, and of 78.7 +/- 4.2 mg/g at 90 days of age in females. A clear cumulative increment of RFI through the filial generations was also found at intermediate growth ages. The frequently argued nongenetic transmission of the nutritional deficiencies from parents to descendants was corroborated with the present results. Such cumulative effect was evident at ages before the AFP was reached; i.e., when the decrement in body mass of the undernourished animals was not yet equilibrated with the amount of available nutrients.  相似文献   
96.
Polydactyly and syndactyly are digital abnormalities in limb‐associated birth defects usually caused by genetic disorders. In this study, a five‐generation Chinese pedigree was found with triphalangeal thumb polysyndactyly syndrome (TPTPS), showing an autosomal dominant pattern of inheritance. We utilized linkage analysis and whole genome sequencing (WGS) for the genetic diagnosis of this pedigree. Linkage analysis was performed using a genome‐wide single nucleotide polymorphism (SNP) chip and three genomic regions were identified in chromosomes 2, 6, and 7 with significant linkage signals. WGS discovered a copy number variation (CNV) mutation caused by a large duplication region at the tail of chromosome 7 located in exons 1–5 of the LMBR1 gene, including the zone of polarizing activity regulatory sequence (ZRS), with a length of approximately 180 kb. A real‐time polymerase chain reaction (PCR) assay confirmed the duplication. The findings of our study supported the notion that large duplications including the ZRS caused TPTPS. Our study showed that linkage analysis in combination with WGS could successfully identify the disease locus and causative mutation in TPTPS, which could help elucidate the molecular mechanisms and genotype–phenotype correlations in polydactyly.  相似文献   
97.
The effect of caspase inhibitors on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 267.4 murine macrophage cells was investigated. Pretreatment of RAW cells with a broad caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK), resulted in a striking reduction in LPS-induced NO production. Z-VAD-FMK inhibited LPS-induced NF-kappaB activation. Furthermore, it blocked phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) but not that of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinases. Similarly, a caspase 3-specific inhibitor, Z-Asp-Glu-Val-Asp-fluoromethylketone, inhibited NO production, NF-kappaB activation, and JNK/SAPK phosphorylation in LPS-stimulated RAW cells. The attenuated NO production was due to inhibition of the expression of an inducible-type NO synthase (iNOS). The overexpression of the dominant negative mutant of JNK/SAPK and the addition of a JNK/SAPK inhibitor blocked iNOS expression but did not block LPS-induced caspase 3 activation. It was therefore suggested that the inhibition of caspase 3 might abrogate LPS-induced NO production by preventing the activation of NF-kappaB and JNK/SAPK. The caspase family, especially caspase 3, is likely to play an important role in the signal transduction for iNOS-mediated NO production in LPS-stimulated mouse macrophages.  相似文献   
98.
99.
目的探讨脊肌萎缩症(SMA)的基因诊断方法.方法基于运动神经元生存基因(SMN)的两个同源拷贝碱基上的差异,应用PCR-酶切分析法对10例临床和病理诊断为Ⅰ、Ⅱ、Ⅲ型SMA的患者及其直系亲属16人、25例正常对照进行SMN基因检测.结果 10例SMA患者中9例患者缺失SMN第7、8号外显子,1例患者仅缺失第7号外显子;正常对照组及患者亲属均未发现外显子缺失.结论 PCR-酶切检测SMN基因第7号、8号外显子缺失是诊断儿童型脊肌萎缩症可靠的基因诊断方法.  相似文献   
100.
鉴于热休克蛋白90β(hsp90β)基因内含子中含有维生素D3受体(VDR)结合位点,为探讨作为核受体家族成员的VDR是否对核受体特异分子伴侣的hsp90β基因的表达具有调控作用,我们开展了本项研究。分别将野生型VDR、含N端(1~133氨基酸残基)及C端(281~427氨基酸残基)片段的VDR突变体真核表达质粒与人hsp90β基因调控片段(-1039/+1531)介导的氯霉素乙酰基转移酶(CAT)报告基因质粒共转染Jurkat细胞,检测正常及经热休克(42℃,1h)处理后细胞裂解液中CAT活性。结果表明VDRN端增强、而C端抑制hsp90β的组成性表达;在热诱导条件下野生型VDR对hsp90β的表达有一定的抑制作用,而其C端片段的抑制较强。为进一步研究VDR对细胞内源性热休克基因表达的影响,我们用RTPCR方法研究了VDR的对细胞内hsp90β基因mRNA水平的影响,发现VDR过表达对hsp90β的热诱导表达明显抑制。结果提示VDR对hsp90β基因的组成性和热诱导表达的调控机制不同。  相似文献   
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