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51.
Establishment and characterization of a chronic infectious mononucleosislike syndrome in common marmosets 总被引:1,自引:0,他引:1
E A Emini J Luka M E Armstrong F S Banker P J Provost G R Pearson 《Journal of medical virology》1986,18(4):369-379
Epstein-Barr virus (EBV) was inoculated into two species of marmosets. Successful infection was established in the majority of the animals of one species, Callithrix jacchus, as evidenced by the development of high, persistent levels of antibody against virus-specific capsid and early nonstructural proteins. Antibodies also were produced against the major membrane antigen and, in some animals, against EBV nuclear antigen (EBNA) 2 but not against EBNA 1. This is the antibody profile normally noted in individuals with chronic infectious mononucleosis (IM). EBV-induced lymphoproliferation was not seen, and EBV-specific proteins were not detected in the peripheral blood lymphocytes of infected animals. Hence, EBV infection in C. jacchus apparently does not generally include extensive B-cell involvement. However, the marmosets clearly are useful as a model for EBV primary infection and also possibly for chronic IM. 相似文献
52.
In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined.Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionaaly,morphologically and immunohistologically,at serial intervals up to 52 weeks after transplantation.Allograft recipients developed progressive proteinuria after 12 weeks,with gradual renal failure ultimately leading to death.At the same time,morphological changes,including progressive arteriosclerosis and glomerulosclerosis ,tubular atrophy and interstitial fibrosis,developed.Immunohistologically,macrophages infiltrated glomeruli during this period and cytokines became unregulated.Our results showed that antigen-independent functional and morphological changes occurred in long-tern kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes. 相似文献
53.
益肾化浊注射液对慢性肾功能衰竭大鼠残余肾中细胞因子含量的影响 总被引:2,自引:0,他引:2
通过观察益肾化浊注射液对5/6肾切除大鼠残余肾中细胞因子含量的影响,益肾化浊注射液延缓慢性肾功能衰竭(CRF)模型大鼠肾功能减退的作用机理。结果显示:益肾化浊注射液可以降低5/6肾切在鼠血清肌,尿素氮(P<0.01),下调肾组织中白细胞介素-1(IL-1)(P<0.05),白细胞介素-8(IL-8)(P<0.05)及肿瘤坏死因子(TNF)(P<0.05)的总体水平,说明益肾化浊注射液可以通过下调5/6肾切除大鼠残余肾中相关细胞因子含量,抑制促炎细胞因子对肾脏的损害,从而延缓CRF的进展。 相似文献
54.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
55.
Expression of cell-matrix molecules and integrin receptors in human liver grafts during chronic rejection 总被引:1,自引:0,他引:1
Ken Hoshino Bjorn Nashan Gustav Steinhoff Rudolf Pichlmayr K. Hoshino 《Transplant international》1994,7(S1):637-640
Abstract The inflammatory response of immune cells to target cells and cell-matrix molecules is regulated by several receptor-ligand molecules. As fibrosis develops in ongoing chronic rejection after liver transplantation, it is of interest to analyze patterns of integrin receptors and cell-matrix molecules in order to study the relation between immune cells and the stromal and parenchymal cells. In the present study, we demonstrated the expression of these molecules in chronic rejected human liver grafts using immunohistochemical techniques. The results showed a differential expression and induction of integrin receptors and cell-matrix molecules on resident liver cells, especially on sinusoids, reflecting a state of chronic inflammation and a specific interaction between integrin receptors and cell-matrix molecules. The patterns of induced integrin receptors on graft-infiltrating cells was closely related to the local production of cell-matrix molecules and reflected the final sequence of a stepwise progress of the inflammatory reaction. 相似文献
56.
M. SILBERSTEIN O. HENNESSY L. LAU 《Journal of Medical Imaging and Radiation Oncology》1992,36(4):334-338
The radiological findings in five patients with pelvic sort tissue neo plasms directly involving the sacroiliac joint, are described. All patients had Computed Tomography (CT) examinations, two of the patients also having Magnetic Resonance Imaging (MRI). The role of imaging in this uncommon entity is discussed as well as the importance of making this diagnosis, thereby excluding unilateral sacroiliitis. The therapeutic implications of this diagnosis relate to local neural involvement, especially the sciatic nerve, and the fact that involvement of the sacroiliac joint by tumors significantly compromises chances of a successful surgical outcome. The role of MR in this condition is not yet certain, but it may prove to be the method of choice in view of its excellent depiction of skeletal neo plasms. 相似文献
57.
Several alkyl[3-(2-chloroethyl)ureido] (CEU) benzene derivatives were prepared as potential anticancer agents. These new compounds were readily prepared in good yields by addition of anilines to 2-chloroethylisocyanate. Their cytotoxic activity was evaluated on human breast cancer (MDA-MB-231), human colon adenocarcinoma (LoVo) and mouse lymphocytic leukemia (P388D1) tumor cell lines. Several new CEUs were significantly more cytotoxic than the nitrogen mustard chlorambucil. The biological activity of these aromatic urea derivatives seems to be related to the nature and position of the alkyl substituents on the aromatic ring. Substitution by branched alkyl groups on position 4 of the aromatic ring led to cytotoxic molecules which are up to 5 times more potent than the standard chlorambucil. 相似文献
58.
M. F. Gagnadoux J. L. Bacri M. Broyer R. Habib 《Pediatric nephrology (Berlin, Germany)》1989,3(1):50-55
Over a 15-year period we observed seven children (four girls, three boys) who presented within the first months of life with severe renal failure and acidosis, associated with hypertension in five patients and polyuria in four. In addition, one patient had a severe cholestatic liver disease. In two families, a similarly affected sibling had died previously. Four patients were referred with the clinical diagnosis of polycystic kidney disease because of moderate enlargement of kidneys, but renal imaging (intravenous pyelography and ultrasonography) did not confirm this diagnosis. A renal biopsy, performed in all patients, showed similar features characterized by a diffuse chronic tubulo-interstitial nephritis (TIN) and particularly by the presence of microcystic dilatation of proximal tubules and Bowman's space. Liver pathology was normal in two patients, including one with hepatomegaly. However, in the patient with cholestasis there was inflammatory portal fibrosis with mild duct proliferation. Progression of the renal disease was extremely rapid and all patients reached end-stage renal failure (ESRF) before the age of 2 years (11–22 months). Two children had successful renal transplants. Although this chronic TIN shares some features with nephronophthisis, we suggest that it represents a distinct entity both on clinical and morphological grounds. The specific clinical features of this disease are its early onset and rapid progression to ESRF. Pathologically, it differs from nephronophthisis by the absence of medullary cysts and thickened tubular basement membranes and by the presence of cortical microcysts. 相似文献
59.
Alexandra H. Heussner Evelyn O'Brien Daniel R. Dietrich 《Experimental and toxicologic pathology》2002,54(2):151-159
The mycotoxin ochratoxin A (OTA) is a potent renal carcinogen in rodents and induces renal fibrosis in pigs. Furthermore, OTA has been associated with the development of renal tumors and nephropathies in humans. Large species- and sex-differences are observed in sensitivity toward OTA-mediated toxicity and carcinogenicity, yet neither the mechanism(s) resulting in OTA toxicity nor the reasons for the observed species- and sex-specificities are known. This paper investigated variations in OTA handling viz binding to renal proteins which could possibly explain the observed differences in OTA susceptibility in vivo and in vitro. The results obtained via a modification of a standard receptor-binding assay demonstrated the presence of at least one homogeneous binding component in renal cortical homogenates from pig, mouse, rat and humans. This component was shown to bind OTA in a specific and saturable manner. A range of compounds selected for their affinity for steroid receptors and/or for various known organic anion transporters were employed in a competition assay to answer the question whether this homogenous OTA binding component represents a steroid-like receptor component or one of the known organic anion transporters of the kidney. Although many of the compounds were able to compete with OTA for protein-binding, the competition patterns displayed a distinct species specificity and did not correspond to the competition patterns associated with presently known organic anion transporters of the kidney in the mouse, rat or human. The data thus suggests the presence of a new organic anion transporter or more likely, a cytosolic binding component of unknown function with high affinity and capacity for OTA binding in humans, rats, mice and possibly pigs. 相似文献
60.
BACKGROUND: Reduced Th1 and elevated Th2 cytokine responses are considered to be a principal mechanism in the generation of the inflammation leading to the manifestations of atopic disease in the skin of atopic dermatitis and in the airways of asthma. If reduced Th1 and elevated Th2 responses are principal determinants of the manifestation of atopic disease it might be expected that subjects with established disease would exhibit differences in their cytokine profiles as compared with atopic patients without clinical disease. OBJECTIVE: To determine whether asymptomatic atopic children exhibit a cytokine imbalance similar to that seen in patients with established atopic disease or if they behave like non-atopic controls. Cytokine responses in a group of children with elevated IgE but no clinical manifestations of disease, atopic children with established disease and non-atopic controls were compared. METHODS: We examined allergen-induced (house dust mite, HDM, rye grass pollen and RYE) cytokine responses in parallel with polyclonal (staphylococcal enterotoxin B, SEB) cytokine responses in a group of children with elevated serum IgE levels without current or past evidence of atopic disease (median age 6.6 years) and compared these with a non-atopic control group (median age 6.5 years) and a group of children with atopic disease (median age 6.7 years). RESULTS: Symptomatic atopic children had reduced SEB-induced IFN-gamma and increased SEB-induced IL-4 and IL-5 as compared with non-atopic controls. In contrast, SEB-induced IFN-gamma, IL-4 and IL-5 production in asymptomatic atopics was not significantly different from the non-atopic control subjects. Allergen-induced Th1 (IFN-gamma) and Th2 (IL-5 and IL-13) cytokine production was increased in both symptomatic atopics and asymptomatic atopics when compared with non-atopic controls. CONCLUSION: The defect in polyclonally induced IFN-gamma production was associated with the clinical manifestation of atopic disease but not the atopic stateper se. This suggests that the global reduction in IFN-gamma is the key determinant of the development of overt atopic disease. In contrast, elevated allergen-induced Th2 cytokine responses in children related to the atopic state per se irrespective of the presence of clinical atopic disease. 相似文献