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71.
The definition of the temporal sequence of appearance of fetal markers during prenatal and early postnatal development in Sertoli and germ cells may be important for understanding the mechanisms underlying their reexpression in disorders of the adult testis. For this reason, we studied the expression of Sertoli and germ cell markers in 25 human testes spanning a period from 8 gestational weeks to 4 years. Well-characterized antibodies were employed to anti-Müllerian hormone (AMH), cytokeratin 18 (CK18), vimentin (VIM), M2A-antigen (M2A), germ cell alkaline phosphatase (GCAP), and somatic angiotensin-converting enzyme (sACE) on formalin-fixed and microwave-pretreated paraffin sections. In Sertoli cells, AMH and VIM were consistently present. While VIM and CK18 were coexpressed in embryonic testes, CK18 was progressively downregulated and completely absent from the 20th gestational week. M2A was absent or moderately expressed in fetal Sertoli cells but increased during further development. In germ cells, M2A was consistently found in primordial germ cells (PGCs) as well as in M- and T1-prespermatogonia. In contrast, sACE and GCAP were absent from PGCs but were a distinct feature of late M- and early T1-prespermatogonia and appeared predominantly between the 18th and the 22nd gestational weeks. Both T2-prespermatogonia and postnatal prespermatogonia were devoid of any marker. While CK18 represents a differentiation marker for fetal Sertoli cells, M2A, GCAP, and sACE can be used as differentiation markers for the discrimination of different germ cell types during human prespermatogenesis. Because various immunophenotypes reflect distinct differentiation stages, this knowledge may be important for understanding adult testicular pathology. 相似文献
72.
目的 :构建重组真核表达质粒pcDNA3.1/IL 18,并在哺乳动物细胞COS 7和Rlc310中进行瞬时和稳定性表达。方法 :从含hIL 18基因的中介载体 pGEM TEasy( pGEM T/hIL 18)中 ,以限制性内切酶酶切方法获得目的片段 ,克隆入真核表达质粒 pcDNA3.1( )中。以脂质体法转染COS 7和Rlc310细胞 ,用RT PCR检测IL 18mRNA的水平 ,免疫组化染色法检测蛋白表达。结果 :构建了hIL 18基因的重组真核表达质粒pcDNA3.1/IL 18,并可在哺乳动物细胞中瞬时、稳定表达 ,获得了可稳定表达hIL 18基因的Rlc310细胞株。结论 :pcDNA3.1/IL 18的构建及表达 ,为IL 18抗肿瘤作用的研究奠定了基础 相似文献
74.
In chronic beryllium disease (CBD), a granulomatous lung disease characterized by hypersensitivity to beryllium salts (BE), BE challenge of bronchoalveolar lavage cells induces IFNgamma. Although nitric oxide (NO) is elevated in CBD airways, the effects of NO on CBD IFNgamma responses are unknown. Here we report that BE-stimulated IFNgamma production in CBD lavage cells was markedly reduced (74%) by the NO generator DETA NONOate. Investigation of IFNgamma-stimulatory cytokine involvement indicated that lavage cell IL-18 was significantly increased (fourfold) by BE and reduced (64%) by DETA NONOate but IL-12 was undetectable. IL-18 production was caspase-1-dependent but caspase 1 inhibition reduced IFNgamma only partially (43%). Specific antibody depletion of lavage cell IL-18 yielded marginal reduction (19%) of IFNgamma. Data are the first to show that: (1) BE stimulates IL-18 as well as IFNgamma in CBD; (2) BE cytokine responses are NO-sensitive; and (3) NO down-regulation of IFNgamma involves other sites in addition to IL-18. 相似文献
75.
Postnatal development of somatostatin-containing neurons in the visual cortex of normal and dark-reared rats 总被引:1,自引:0,他引:1
G. C. Papadopoulos M. E. Cavanagh J. Antonopoulos H. Michaloudi J. G. Parnavelas 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,92(3):473-478
Summary The distribution of somatostatin (SRIF)-immunoreactive neurons in the visual cortical areas 17, 18 and 18a of Wistar rats from birth to adulthood was followed in both normal and dark-reared animals. The SRIF neurons show difference in distribution amongst the three cortical areas studied as early as the first postnatal week. Area 17 was distinguished by fewer SRIF cells in the upper layers (I–III), which results in a lower overall density. The SRIF neurons in all areas appeared to increase in numbers up to about 3 weeks and then decline dramatically to adult levels, which were 14–19% of the peak levels. Although this decline was still obvious, it moderated to 25–31% in dark-reared animals. The greatest effect was seen in area 18 where, at 60 days of age, there were twice as many SRIF cells in darkreared as in normal controls. It is suggested that, under conditions of dark rearing, the overall pattern of development of SRIF neurons, being uninfluenced by extrinsic factors, reveals the cells' genetic potential. 相似文献
76.
严重烧伤患者血清IL-18、sFas和sFasL水平的变化规律及其相关性研究 总被引:2,自引:0,他引:2
目的 :探讨严重烧伤患者血清IL 18、sFas和sFasL水平间的变化及其与病情的关系。方法 :选择烧伤总面积(TBSA)≥ 30 %的严重烧伤患者 30例 ,其中死亡 3例 ;正常对照组 4 5例。采用ELISA法对不同时相点 (伤后 1、3、5、7、14、2 1、2 8和 35天 )患者血中IL 18、sFas和sFasL水平进行检测。结果 :与正常对照组比较 ,患者血清IL 18、sFas和sFasL水平均呈显著性上升 (P <0 0 1~ 0 0 5 ) ,并分别持续至伤后 2 8,2 1和 2 1天 ;感染组患者血清IL 18、sFas和sFasL水平均显著地高于非感染组 (P <0 0 1~ 0 0 5 ) ;死亡组患者血清IL 18水平下降 ,而sFasL水平则升高。患者血清IL 18和sFasL水平与烧伤面积相关 ;患者血清IL 18、sFas和sFasL之间也呈显著正相关 (P <0 0 1)。结论 :患者血清IL 18、sFas和sFasL水平与烧伤严重程度及伤后感染密切相关 ,在烧伤后免疫功能及凋亡调控中可能起一定作用。 相似文献
77.
目的:获取rhIL-18原核表达产物并研究其活性。方法:用本室构建的含基因重组表达载体PBV220-IL-18的大肠杆菌DHSot,经42℃热诱导表达和包涵体提取纯化后获取rhIL-18蛋白;采用ELISA试剂盒检测rhIL-18刺激PBMC分泌IFN-γ的活性及MTT法检测其对NK细胞杀伤K562细胞自然杀伤活性;同时用荷瘤小鼠模型检测其体内抗瘤功能。结果:诱导含重组表达载体PBV220-IL-18的大肠杆菌D145ct后,蛋白电泳显示出一条相对分子量(Mτ)为18000的蛋白条带;10μg rhIL-18蛋白体外刺激PBMC后,其分泌IFN-γ的能力与对照组相比提高了8倍,细胞毒性提高3倍;同时rhIL-18蛋白能明显抑制肿瘤生长和延长荷瘤鼠生存期。结论:获得了有免疫调节功能和抗肿瘤活性的rhIL-18蛋白。为今后IL-18重组产物的研制和开展肿瘤的生物治疗提供了实验依据。 相似文献
78.
IL-1, IL-18, and IL-33 families of cytokines 总被引:4,自引:0,他引:4
Summary: The interleukin-1 (IL-1), IL-18, and IL-33 families of cytokines are related by mechanism of origin, receptor structure, and signal transduction pathways utilized. All three cytokines are synthesized as precursor molecules and cleaved by the enzyme caspase-1 before or during release from the cell. The NALP-3 inflammasome is of crucial importance in generating active caspase-1. The IL-1 family contains two agonists, IL-1α and IL-1β, a specific inhibitor, IL-1 receptor antagonist (IL-1Ra), and two receptors, the biologically active type IL-1R and inactive type II IL-1R. Both IL-1RI and IL-33R utilize the same interacting accessory protein (IL-1RAcP). The balance between IL-1 and IL-1Ra is important in preventing disease in various organs, and excess production of IL-1 has been implicated in many human diseases. The IL-18 family also contains a specific inhibitor, the IL-18-binding protein (IL-18BP), which binds IL-18 in the fluid phase. The IL-18 receptor is similar to the IL-1 receptor complex, including a single ligand-binding chain and a different interacting accessory protein. IL-18 provides an important link between the innate and adaptive immune responses. Newly described IL-33 binds to the orphan IL-1 family receptor T1/ST2 and stimulates T-helper 2 responses as well as mast cells. 相似文献
79.
目的 探讨18q21在人胰腺导管腺癌和慢性胰腺炎中杂合性缺失(LOH)的情况及其相关因素.方法 选择18q21上的位点RP11-729G3和RP11-850A17作为目的 片段,选择接近18号染色体着丝粒的位点RP11-621L6作为参照位点,利用细菌人工染色体(BAC)提取、纯化相应位点的DNA,用切口平移法分别标记生物素和地高辛后制成双色探针,应用荧光原位杂交技术(FISH)检测30例胰腺导管腺癌和10例慢性胰腺炎石蜡包埋组织切片中18q21 LOH情况,并收集、整理相应临床病理资料进行相关性分析.结果 30例胰腺导管腺癌中在RP11-729G3位点有25例(83.3%)有LOH,在RP11-850A17位点26例(86.6%)有LOH,其中25例在RP11-729G3和fuP11-850A17两个位点均有LOH,1例仅在RP11-850A17位点有LOH.10例慢性胰腺炎中均未发现18q21 LOH.经统计学分析发现,18q21 LOH在慢性胰腺炎和胰腺导管腺癌中差异有统计学意义(P<0.01),且RP11-729G3和RP11-850A17两个位点LOH有高度相关性(Phj系数=0.877),但和临床病理各因素间未发现明显相关.结论 18q21 LOH在胰腺导管腺癌中属于高频事件,并且位点RP11-729G3和RP11-850A17的LOH有高度相关性,可能在胰腺导管腺癌发生发展中起重要作用.在临床诊断中18q21LOH也能作为较特异的标记辅助诊断. 相似文献
80.
Monosomy for the short arm of chromosome 18 is one of the most frequent autosomal deletions observed. While most cases result from terminal deletion of 18p, 16% of cases reported were as a result of an unbalanced whole arm translocation resulting in monosomy 18p. The origin and structure of these derivative chromosomes were reported in only a few cases. We report the prenatal diagnosis and characterization of a new case of monosomy 18p as a result of an unbalanced whole arm translocation. Amniocentesis was performed at 15 weeks of gestation on a 34-year-old woman initially referred for advanced maternal age. Holoprosencephaly was identified by ultrasound at the time of amniocentesis. Karyotype analysis showed an unbalanced whole arm translocation between the long arm of one chromosome 18 and the long arm of one chromosome 22, 45,XX,der(18;22)(q10;q10), in all metaphases. In effect, the fetus had monosomy for 18p. Parental karyotypes were normal, suggesting a de novo origin for the der(18;22). Fluorescence in situ hybridization (FISH) analysis was performed with alpha-satellite probes D18Z1 and D14Z1/D22Z1 to identify the origin of the centromere on the der(18;22). Signal was observed with both probes, indicating that the centromere was composed of alpha-satellite DNA from both constituent chromosomes. Genotyping of the fetus and her parents with chromosome 18p STS marker D18S391 showed only the paternal 187 bp allele was present in the fetus, indicating that it was the maternal chromosome 18 involved in the der(18;22). This case and previous reports show that de novo unbalanced whole arm translocations are more likely to retain alpha-satellite sequences from the two chromosomes involved. 相似文献