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21.
SUMMARY: Transforming growth factor-β (TGF-β) has been considered the principal cytokine involved in the pathogenesis of renal fibrosis. In the present study, we evaluated TGF-β activity in occasional samples from 22 normal individuals and 29 patients (11 with focal glomerulosclerosis, 11 with membranous nephropathy, five with Berger disease, one with type I membranoproliferative glomerulonephritis and one with postinfectious glomerulonephritis) using a CCL-64 mink lung cell growth inhibition assay.
A significantly increased urinary TGF-β activity (reported in relation to urine creatinine, Ucreat, and median) was observed in patients with glomerulonephritis compared with normal individuals ( P <0.01). the patients with Berger disease [median (Md) = 9.96/10 μg Ucreat.], membranous glomerulonephritis (Md = 7.23/10 μg Ucreat.) and focal glomerulosclerosis (Md = 16.6/10 μg Ucreat.) showed higher urinary TGF-β than normal individuals (Md = 1.09/10 μg Ucreat.) ( P <0.01). We found a positive correlation between the TGF-β activity in the urine of these patients and the incidence of segmental glomerulosclerosis ( r = 0.45, P <0.05) and their plasma creatinine levels ( r = 0.87, P <0.01). A negative correlation was observed between the TGF-β activity in the urine of these patients and their creatinine clearance ( r =−0.75, P <0.01).
Our data suggest that measurement of urinary TGF-β activity could be a useful non-invasive procedure for the evaluation of renal TGF-β production, permitting the assessment of prognosis and the evaluation of therapeutic efficacy in patients with renal disease.  相似文献   
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运用Ca2+指示剂Fura-2作为细胞内钙离子的荧光探针,利用AR—CM—MIC阳离子测定系统,检测了分离的神经细胞内游离钙及其变化,并观测了DGAVP和Org2766对蛋白质合成抑制剂茴香霉素(ANI)引起细胞内钙离子浓度([Ca2+]i)变化的影响。结果表明茴香霉素可使[Ca2+]i显著升高,且有量效关系;DGAVP本身并不引起[Ca2+]i发生显著变化,但适当剂量的DGAVP可显著对抗一定剂量范围内ANI升高[Ca2+]i的作用,提示DGAVP对抗ANI的蛋白质合成抑制效应可能是通过拮抗ANI升高[Ca2+]i这一途径实现的,另一神经肽Org2766则可能不是通过这一机制发生作用。从细胞内Ca2+的角度看,这两种肽的作用机理显然是不同的。  相似文献   
23.
Ivy  SP; Olshefski  RS; Taylor  BJ; Patel  KM; Reaman  GH 《Blood》1996,88(1):309-318
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents.  相似文献   
24.
We tested whether significant leukocyte infiltration occurs in a mouse model of permanent cerebral ischemia. C57BL6/J male mice underwent either permanent (3 or 24 hours) or transient (1 or 2 hours+22- to 23-hour reperfusion) middle cerebral artery occlusion (MCAO). Using flow cytometry, we observed ∼15,000 leukocytes (CD45+high cells) in the ischemic hemisphere as early as 3 hours after permanent MCAO (pMCAO), comprising ∼40% lymphoid cells and ∼60% myeloid cells. Neutrophils were the predominant cell type entering the brain, and were increased to ∼5,000 as early as 3 hours after pMCAO. Several cell types (monocytes, macrophages, B lymphocytes, CD8+ T lymphocytes, and natural killer cells) were also increased at 3 hours to levels sustained for 24 hours, whereas others (CD4+ T cells, natural killer T cells, and dendritic cells) were unchanged at 3 hours, but were increased by 24 hours after pMCAO. Immunohistochemical analysis revealed that leukocytes typically had entered and widely dispersed throughout the parenchyma of the infarct within 3 hours. Moreover, compared with pMCAO, there were ∼50% fewer infiltrating leukocytes at 24 hours after transient MCAO (tMCAO), independent of infarct size. Microglial cell numbers were bilaterally increased in both models. These findings indicate that a profound infiltration of inflammatory cells occurs in the brain early after focal ischemia, especially without reperfusion.  相似文献   
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目的:探索糖稳态调节细胞定向分化的基因改造方案思路.方法:①研究构建的解除干细胞分化抑制状态的信号传导与转录激活因子-3(STAT-3)基因载体,检测其介导目的基因感染ARIP等细胞基因表达;②研究构建的活化配体DL诱导N信号、在"旁侧抑制"过程中扮演重要角色的Kuzbanian(KUZ)基因载体在转基因小鼠表达后糖稳态调节细胞的分化.结果:在完成的STAT-3腺病毒基因载体生产了腺病毒,用带有目的基因的腺病毒对ARIP靶细胞进行感染,3 d后,荧光显微镜观察时,活细胞、固定液固定细胞均看到了构建基因中绿色荧光蛋白成功、高效的阳性表达报告.在完成的Kuzbanian(KUZ)基因载体构建、转基因、动物模型、小鼠品系鉴定后,用非放射性原位杂交实验对胰腺靶细胞的mRNA进行检测,获得了预期的阳性结果.结论:通过用某些分化抑制性基因的显性失活形式(DN)竞争性预先解除干细胞分化的抑制状态,然后再定向分化诱导使之朝向期望的目标细胞方向分化,可能是糖稳态细胞定向分化的可行途径之一.  相似文献   
27.
This study comprised 103 preterm infants with a gestational age less than 33 weeks who were born in Tampere University Hospital and who were followed up to two years of age. Sixty-four perinatal variables were compared to ultrasound findings in the neonatal period and neurologic handicap at the age of two years. Duration of hypocarbia (PCO2 < or = 30 mmHg) during the first 72 h and hyperbilirubinemia (the mean level of serum total bilirubin) at three days of age were independently and significantly related to periventricular leukomalacia, but not directly to cerebral palsy. The only perinatal variables related independently and significantly to cerebral palsy at two years of age were periventricular leukomalacia and ventriculomegaly. According to these results, periventricular leukomalacia was the main predictor of cerebral palsy in preterm infants. In addition to hypocarbia, hyperbilirubinemia may also be involved in the pathogenesis of extensive (severe cystic) periventricular leukomalacia.  相似文献   
28.
Immunological and functional protein S, protein C and antithrombin III levels and anticoagulant responses to activated protein C were measured in 24 patients with stroke in childhood. No hereditary deficiencies were found. The protein S levels in healthy controls of younger age did not differ from the adult levels. For optimal screening of protein S deficiency, measurements using functional as well as immunological assays are recommended. Appropriate criteria for the diagnosis of the deficiencies must be carefully applied if unnecessary anxiety and inappropriate treatment of children are to be avoided.  相似文献   
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