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31.
Two unrelated adult sibling cases (36- and 32-year-old females) of Juvenile hyaline fibromatosis are presented. The parents of one of these patients were non-consanguineous but natives of a small Island, and one elder sister among four siblings was affected with the same disease. The parents of the other patient were consanguineous, and one other sibling suffered from the identical disease. Both patients presented with multiple subcutaneous nodules, which they had had since infancy, and had undergone numerous surgical excisions. Light microscopy examination of skin lesions from both patients showed identical histology; an abundance of a homogenous, amorphous, eosinophlllc extracellular matrix in which spindle-shaped cells were embedded. Electron microscopically, the spindle-shaped cells had hypertrophic Golgi apparatus and dilated, rough endoplasmlc reticulum. Fine flbrillar and granular material-filled structures, the contents of which were occasionally released into the extracellular matrix, were also seen, immunohistochemically, the spindle-shaped cells were vlmentin-positive but negative for α-smooth muscle actln and S-100 protein, and the hyaline ground substance was positive for type I and type III collagen but negative for type II and type IV collagen and tenascin. Matrix metalloprotelnase-1, -2, and -9, and tissue inhibitor of matrix metalloproteinase (TlMP)-2 was positive but TIMP-1 was negative. A review of 39 cases of juvenile hyaline fibromatosis In the literature is also presented. In summary, skin lesions may be the most outstanding symptoms of juvenile hyaline fibromatosis, but joint contracture and gingival hypertrophy precede the skin manifestation.  相似文献   
32.
Prolonged, strenuous exercise may lead to suppressive effects on the immune system, which might be responsible for a greater susceptibility to opportunistic infections. The aim of this study was to examine the influence of carbohydrate substitution (CHS) during prolonged, strenuous exercise on neutrophil granulocytes and their oxidative burst (intracellular oxidation of dihydrorhodamine123 to rhodamine123 after induction by formylized 1-methionyl-1-leucyl-1-phenylalanin) using flow cytometry. In three trials different concentrations of CHS (placebo compared to 6% and 12% CHS; 50 ml·kg–1) were given randomly to 14 endurance trained cyclists [mean (SD) age 25 (5) years, maximal oxygen uptake 67 (6) ml·min–1·kg–1] cycling for 4 h in a steady state at 70% of their individual anaerobic threshold. Blood samples were taken before, immediately after cessation, 1 h and 19 h after exercise. A significant rise in neutrophil counts was observed immediately after cessation and 1 h after exercise with a return to normal rest values 19 h after exercise for all three conditions (P<0.001). The relative proportions of rhodamine123+ neutrophils were significantly diminished in all three conditions 1 h after exercise (P<0.01), while the mean fluorescence intensity was lowest in the placebo trial and differed significantly to the 12% CHS trial (P=0.024) and almost significantly to the 6% CHS trial (P=0.052). In conclusion, these data suggest a beneficial effect of CHS on the neutrophil oxidative burst and a possible attenuation of the susceptibility to infections, presumably due to the reduction of metabolic stress in prolonged, strenuous exercise. Electronic Publication  相似文献   
33.
A radioimmunoassay (RIA) using polystyrene beads as the solid phase for cytomegalovirus (CMV) antigen and iodinated immunosorbent purified anti-human IgG, IgM, and IgA as indicator antibodies was developed for the detection of immunoglobulin class-specific antibodies to CMV. An antigen prepared from extracellular virus was essential for reliable results, and a preparation ultracentrifuged and sonicated twice was better than a crude antigen. The optimal antigen gave low cpm values with a negative reference serum, resulting in cpm ratios of 10 or higher between early convalescent phase serum and negative reference serum. Of six patients with an increase in CMV CF titres, all six had an increase in RIA IgG titres, four had an increase in IgA titres, and all had IgM antibodies. The IgG titres were high, up to 1/64,000. In a group of 17 infants negative in CMV CF test, 14 had CMV IgG antibodies in RIA test, indicating mainly low levels of maternal antibodies. In six of seven patients with CMV isolations from urine specimens, an increase in IgG or IgA titres or the presence of IgM antibodies was found, and only one of these patients had an increase in CMV CF titre. The specificity of the developed CMV RIA test was further demonstrated by detecting no significant increase in RIA titres in serum specimens of patients with primary herpes simplex infection, chickenpox, herpes zoster, or infectious mononucleosis.  相似文献   
34.
Extracellular levels of striatal gamma-aminobutyric acid (GABA) and taurine were monitored during insulin-induced hypoglycemia using microdialysis. At the onset of isoelectricity in the electroencephalogram (EEG), a transient 5-fold increase in the levels of GABA occurred. Taurine levels increased 5 min following the onset of isoelectricity and continued to increase during the entire isoelectric period. The results demonstrate that events associated with the onset of isoelectricity during hypoglycemia trigger an increase in extracellular concentrations of GABA and taurine. The discrepancy in time-course of these changes may reflect differences in compartmentation, function and metabolism of the two amino acids.  相似文献   
35.
Bacterial DNA stimulates macrophages, monocytes, B lymphocytes, NK cells, and dendritic cells in a CpG-dependent manner. In this work we demonstrate that bacterial DNA, but not mammalian DNA, induces human neutrophil activation as assessed by L-selectin shedding, CD11b upregulation, and stimulation of cellular shape change, IL-8 secretion, and cell migration. Induction of these responses is not dependent on the presence of unmethylated CpG motifs, as neutrophil stimulatory properties were neither modified by CpG-methylation of bacterial DNA nor reproduced by oligonucleotides bearing CpG motifs. We found that human neutrophils express Toll-like receptor (TLR) 9 mRNA. However, as expected for a CpG-independent mechanism, activation does not involve a TLR9-dependent signaling pathway; neutrophil stimulation was not prevented by immobilization of bacterial DNA or by wortmannin or chloroquine, two agents that inhibit TLR9 signaling. Of note, both single-stranded and double-stranded DNA were able to induce activation, suggesting that neutrophils might be activated by bacterial DNA at inflammatory foci even in the absence of conditions required to induce DNA denaturation. Our findings provide the first evidence that neutrophils might be alerted to the presence of invading bacteria through recognition of its DNA via a novel mechanism not involving CpG motifs.  相似文献   
36.
37.
目的分析脊柱术后医院感染患者病原菌分布特征及中性粒细胞64(CD64)和中性粒细胞百分比(NEU%)表达情况。方法选取2017年6月-2019年6月天津市天津医院收治的脊柱术后医院感染患者51例为感染组,并选取同期于医院就诊的脊柱术后未发生感染患者51例为未感染组。分析感染组患者病原菌情况,检测患者NEU和CD64水平;ROC曲线分析CD64和NEU%指标水平预测感染的诊断价值。结果 51例感染患者共培养分离病原菌78株,其中革兰阴性菌42株(53.85%)、革兰阳性菌33株(42.31%)、真菌3株(3.85%),以铜绿假单胞菌及金黄色葡萄球菌为主。术后7 d,感染组体温、WBC、中性粒细胞计数、CRP、ESR分别为(38.47±0.52)℃、(8.34±2.17)×109/L、(5.98±1.94)×109/L、(54.52±19.93)mg/L、(51.74±21.88)mm/h均高于非感染组(P<0.05)。术后7 d,感染组CD64、NEU%分别为(8.87±2.13)%、(84.93±13.39)高于非感染组(P<0.05)。CD64指数与NEU%水平诊断ROC曲线下面积分别为0.922、0.826。结论脊柱术后医院感染以革兰阴性菌为主,CD64及NEU%水平有助于脊柱术后医院感染的早期诊断。  相似文献   
38.
目的 :观察整合素血小板膜糖蛋白Ⅱb、Ⅲa(GPⅡb、GPⅢa)在人类系膜增殖肾炎 (MsPGN)中肾内表达 ,探讨GPⅡb Ⅲa在MsPGN的作用。方法 :18例肾活检标本均行光镜HE、PAS、PASM Masson染色 ,电镜及免疫荧光检查 ,以SABC法测定肾组织中GPⅡb、GPⅢa、P 选择素 (P 140 )、纤维连接蛋白 (FN)、粘连蛋白 (LN)表达与正常对照组分别比较 ,并行计算机图像分析。结果 :PAS阳性物 (PAS+ )、PASM阳性物 (PASM+ )及FN、LN明显增生 ;GPⅡb、GPⅢa、P 140表达上调 ;肾小球细胞数 (n)、平均肾小球体积 (AVG)及肾小球硬化指数显著增加 ;肾小管、间质轻度受损。结论 :GPⅡb、GPⅢa在肾小球及肾小管间质表达上调与系膜细胞基质增生、细胞浸润、肾小球硬化相关 ;可能与肾小球疾病中凝血功能紊乱、血小板在肾脏的致病作用相关  相似文献   
39.
Alopecia is one of the common symptoms after high-dose radiation exposure. In our experiments, neonatal mice that received 7 Gy X-ray exhibited defects in overall hair growth, except for their cheeks. This phenomenon might suggest that some substances were secreted and prevented hair follicle loss in the infant tissues around their cheeks after radiation damage. In this study, we focused on exosome-like vesicles (ELV) secreted from cheek skin tissues and back skin tissues, as control, and examined their radiation protective effects on mouse fibroblast cell lines. We observed that ELV from irradiated cheek skin showed protective effects from radiation. Our results suggest that ELV from radiation-exposed cheek skin tissue is one of the secreted factors that prevent hair follicle loss after high-dose radiation.  相似文献   
40.
Type IV collagenases in invasive tumors   总被引:11,自引:0,他引:11  
Summary The matrix metalloproteinases appear to be elevated in tumors with metastatic potential, and may well be involved in penetration of the basement membrane and degradation of extracellular proteins including type IV collagen. An imbalance between the 72 kDa and 92 kDa type IV collagenases and the associated tissue inhibitors of these metalloproteinases (TIMPs) may therefore have a role in the invasive phenotype. Cultured tumor cells with invasive potential secrete both type IV collagenases, though in tumors there is some evidence that the 72 kDa form at least may be produced by stromal cells at the invading tumor front rather than primarily by the tumor cells themselves, while the 92 kDa form may be synthesized in macrophages near the front. These collagenases are elevated in invasive as compared within situ tumor components, but their specific roles and prognostic significance are not yet established.  相似文献   
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