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Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
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BACKGROUND: Contact with immunomodulatory factors, such as LPS, in early infancy is associated with decreased allergen sensitization. OBJECTIVE: We sought to study the effects of systemic or airway exposure with LPS on the development of allergen sensitization, eosinophilic airway inflammation, and increased in vivo airway reactivity (AR) in a mouse model. METHODS: BALB/c mice were systemically sensitized with ovalbumin (OVA) plus adjuvant on days 1 and 14 and challenged through the airways with allergen on days 34 to 36. We performed measurement of OVA-specific IgE serum levels, in vitro T(H)2 cytokine production, differential cell counts in bronchoalveolar lavage fluids, and assessment of in vivo AR to inhaled methacholine by means of barometric whole-body plethysmography. RESULTS: Systemic LPS administration before OVA sensitization reduced OVA-specific IgE serum levels (426 +/- 76 vs 880 +/- 104 U/mL, P <.01), T(H)2 cytokine production by splenic mononuclear cells (IL-4: 0.08 +/- 0.01 vs 0.17 +/- 0.01 ng/mL; IL-5: 1.98 +/- 0.52 vs 4.11 +/- 0.54 ng/mL; P <.01), and extent of airway eosinophilia (total cell counts: 93 vs 376 x 10(3)/mL; eosinophils: 23% vs 51%; P <.01) compared with that in OVA-sensitized mice. Local LPS administration to sensitized mice before airway allergen challenges particularly induced IFN-gamma production by peribronchial lymph node cells in vitro (1718 +/- 315 vs 483 +/- 103 ng/mL, P <.01) associated with reduced airway eosinophilia compared with that seen in OVA-sensitized mice. Development of increased AR was not affected by systemic or local LPS exposure. Inhibitory effects of LPS on allergen sensitization and eosinophilic airway inflammation were inhibited by administration of anti-IL-12 antibodies before LPS exposure. CONCLUSION: These data indicate that local and systemic application of LPS modulates systemic and local T(H)1/T(H)2 immune responses in a distinct but similarly IL-12-dependent mode.  相似文献   
45.
BACKGROUND/OBJECTIVES: An ineffective cytokine response is thought to be one of the reasons for the failure to suppress hepatitis B virus (HBV) replication and to eliminate the virus. We investigated the serum levels of interleukin (IL)-6, IL-10, IL-12, and interferon (IFN)-gamma in HBV-infected Vietnamese patients to determine whether they were related to the outcome of HBV infection. STUDY DESIGN: Samples from a total of 154 HBV-infected patients with well-characterised clinical profiles and 56 healthy controls were assessed. RESULTS: Serum IL-6 levels, which were inversely correlated with transaminase levels, were highest in patients with liver cirrhosis (LC) and hepatocellular carcinoma (HCC) and lowest in those with either asymptomatic (ASYM), acute or chronic HBV, and thus, represented the best marker of HBV-related clinical progression. Compared with the healthy control group, serum IL-12 was uniformly elevated in all HBV-infected patients apart from those with ASYM infections, implying no impairment of production of this cytokine in HBV-infected individuals. Serum IL-10 and IFN-gamma levels, however, were uniformly low and showed no association with clinical presentation. Cytokine profiles were not influenced by the presence of hepatitis B e antigen (HbeAg). CONCLUSIONS: Serum IL-6 and IL-12 but not IL-10 and IFN-gamma are associated with the clinical presentation in HBV-infected Vietnamese patients.  相似文献   
46.
Hydrosalpinges adversely affect markers of endometrial receptivity   总被引:22,自引:10,他引:22  
While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.   相似文献   
47.
采用生物素结合的葡聚糖胺顺行示踪法研究了大鼠视皮质主要胼胝体投射区即17/18a交界区胼胝体轴突的生后发育和形态。在生后5天时,此交界区胼胝体轴突从白质向灰质Ⅰ层垂直生长,在灰质内仅有极少量的侧支抽芽。至生后13天时,皮质Ⅰ层最先出现致密的由胼胝体轴突终支组成的终末丛。到生后17天时,类似的终末丛也见于皮质Ⅱ/Ⅲ,Ⅴ和Ⅵ层,这种分布型式与成年大鼠者相似。以上结果表明,绝大部分胼胝体轴突首先生长到达Ⅰ层并先在Ⅰ层发出终支,然后再在其它皮质层发出侧支及终支,因而提示皮质Ⅰ层在胼胝体联系的生后发育中可能发挥重要作用。  相似文献   
48.
Hearing loss is an important health problem in the elderly which sometimes leads to social isolation. In a study with 62 patients, the diagnostic value of four simple tests for screening for hearing loss in general practice was examined. When paying attention to the loudness of the whispering, the whispered voice test can be a valuable test for assessment of hearing loss in general practice.  相似文献   
49.
Summary The expression of theNeuralCell AdhesionMolecule, NCAM, in mouse gonads and ducts was studied from fetal life to maturity. The methods used were immunocytochemical staining and Western blotting. The immunocytochemical studies showed that the only structures that remain NCAM-positive throughout life were the mesonephric-derived rete ovarii and rete testis. Also in the fetal gonads some somatic cell lining the groups of differentiating germ cells were stained. In the immature as well as in the mature ovary the granulosa cells and oocytes of growing and large follicles — but not of small follicles — were stained. A particularly strong staining of the cytoplasm of the oocyte, healthy as well as atretic, was seen. All cells of the testis remained negative except for weakly stained residual bodies and late spermatids. At all ages the male ducts showed only weak staining, whereas in the female Müllerian duct the epithelium became strongly positive at puberty. The stroma of the Müllerian duct was positive during a transitory period around day 16 of fetal life in both sexes. One-dimensional gel immunoblotting of total protein from gonads, rete and ducts from immature and mature mice showed that only the two largest isoforms of NCAM (NCAM-A and NCAM-B) were present. The gonads and the rete of both sexes and the adult uterus expressed only NCAM-B, whereas NCAM-A was also detected in the adult epididymis. The present findings suggest that NCAM may be involved in the normal development and formation of both the gonads and ducts. In particular, NCAM may play a part in sustaining the integrity of the rete testis, thus ensuring the pathway for spermatozoa from the testis to the epididymis. Furthermore this cell adhesion molecule may also be important for follicular growth and differentiation.  相似文献   
50.
There is now enough experience with the use of double-blind, placebo-controlled, food challenge (DBPCFC) to recommend its use as an office procedure for most patients complaining of adverse reactions to foods. This manual discusses the practical methods required for the allergist to undertake DBPCFC in the office. Thorough histories supplemented by food allergen skin testing are used to design a DBPCFC that carefully attempts to reproduce the history of food-induced symptoms described by the patient. Precautions that must be taken are delineated before challenge, as is treatment that may be required if a reaction occurs. For those foods to which challenges are positive, longitudinal evaluation with repeated challenge at appropriate intervals help to determine whether or not the problem will resolve over a period of time.  相似文献   
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