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61.
The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor. 相似文献
62.
Inhibiting complement anaphlytoxin C5a during sepsis may prevent sepsis mortality. Although human anti-C5 antibodies exist, their therapeutic use in microbial sepsis has been avoided because of the hypothesis that inhibiting C5b will prevent formation of the bactericidal membrane attack complex (MAC) and worsen clinical outcome. We wished to test the hypothesis that inhibition of C5 would improve outcomes in sepsis. Sepsis was induced in rats by laparotomy and cecal ligation and puncture (CLP) by an IACUC-approved protocol. Sham animals underwent laparotomy without CLP. Following CLP rats were randomized to receive a single IV dose of purified IgG ant-C5 antibody (Ab) or control IgG Ab. Anti-C5 Ab treated rats (n = 20) had significantly lower mortality vs. controls (n = 21), 20% vs. 52% (P = 0.019, log-rank). Analysis of bacterial load by culture of spleen and liver homogenates showed a reduction in colony forming units in anti-C5 Ab treated rats vs. control IgG (P = 0.003 and 0.009, respectively). Anti-C5 treatment reduced lung injury as measured by total MPO content of lung tissue (P = 0.024). Finally, rats genetically deficient in C6 production, unable to form MAC but capable of producing C5a and C5b, were protected from CLP-induced sepsis mortality. Our results show that in anti-C5 antibody therapy prevents CLP sepsis-induced mortality and improves lung injury. Inhibition of the complement MAC does not increase bacterial load or mortality, therefore, the use of anti-C5 therapy may be beneficial rather than detrimental in sepsis. 相似文献
63.
Xun Wang Rongzuo Xu Grant Abernathey Jordan Taylor M B Alzghoul Kevin Hannon Gregory H Hockerman Amber L Pond 《Developmental dynamics》2008,237(9):2430-2437
The Kv11.1 (also ERG1) K(+) channel underlies cardiac I(Kr), a current that contributes to repolarization in mammalian heart. In mice, I(Kr) current density decreases with development and studies suggest that changes in the structure and/or properties of the heteromultimeric I(Kr)/Kv11.1 channel are responsible. Here, using immunohistochemistry, we report that total Kv11.1 alpha subunit protein is more abundant in neonatal heart and is distributed throughout both adult and neonatal ventricles with greater abundance in epicardia. Immunoblots reveal that the alpha subunit alternative splice variant, Kv11.1a, is more abundant in adult heart while the Kv11.1b variant is more abundant in neonatal heart. Additionally, MinK channel subunit protein is shown to co-assemble with Kv11.1 protein and is more abundant in neonatal heart. In summary, Kv11.1/I(Kr) channel composition varies developmentally and the higher I(Kr) current density in neonatal heart is likely attributable to higher abundance of Kv11.1/I(Kr) channels, more specifically, the Kv11.1b splice variant. 相似文献
64.
Summary Seventy-one Caucasian orbits (36 right, 35 left) were studied by dissection. The diameter of the ophthalmic a. (2 mm from the origin) was 1.54 ± 0.04 mm (male) and 1.31 ± 0.05 mm (female). In individual cases, there were no significant differences in vessel diameter between the right and left sides but, differences in vessel diameter between males and females were more commonly observed in the arteries which leave the orbit (extraorbital group), the individual vessels having a larger diameter in males. The incidence of the ophthalmic a. passing in the orbit medially under the optic n. was 18.6%. The lacrimal a. was observed to arise from the ophthalmic a. in only 82.5% of the cases examined, 15.9% of the cases showed the origin to be at the anastomotic branch of the middle meningealThis article is dedicated to Pr Dr Hoepke on occasion of his 100th birthday 相似文献
65.
The effects of electrical stimulation of the median raphe nucleus on neuronal discharges in the medial septal area and electrical activity of the hippocampus were examined in urethane-anaesthetized rats. Two cell populations in the medial septal area were differentiated on the basis of their spontaneous discharge pattern, response to median raphe nucleus stimulation and whether or not they were antidromically activated following hippocampal stimulation. Medial septal area cells classified as I-neurones discharge in an irregular pattern which was unrelated to hippocampal activity. In contrast, B-neurones discharge in either rhythmic bursts or in an irregular manner which were related to hippocampal ‘theta’ or ‘desynchronization’, respectively. Single pulse stimulation of the median raphe nucleus inhibited the spontaneous discharge of I-neurones but did not influence the firing of B-neurones or hippocampal activity. Repetitive stimulation of the median raphe nucleus resulted in a prolonged inhibition of I-neurones, a disruption of the bursting discharge of B-neurones, and desynchronization of the hippocampal ‘theta’. The effects of median raphe nucleus stimulation were blocked by pretreatment with parachlorophenylalanine suggesting that a serotonin-containing system originating in the median raphe nucleus may be involved in mediating these responses. 相似文献
66.
Elizabeth Farish Judith F. Barnes Hilary A. Rolton Keith Spowart Colin D. Fletcher David M. Hart 《Maturitas》1994,20(2-3):215-219
Objective: To determine the effects of tibolone, a synthetic steroid used to alleviate climacteric symptoms and prevent osteoporosis, on lipoprotein metabolism, with particular reference to lipoprotein(a) levels and HDL subfraction profiles.Design: Thirty nine postmenopausal women were treated with tibolone (Livial) 2.5 mg/day for 6 months and fasting serum lipoprotein levels were estimated at 0, 2, 4 and 6 months. Results: Lipoprotein(a) levels were reduced significantly over the 6 months from a median level of 245 (range <60–780) mg/I to 152 (range <60–530) mg/l, a reduction of 39% in the median level. A decrease was observed in approximately two thirds of the women. Reductions were noted in all 6 subjects whose pretreatment levels were high, although concentrations remained at a level associated with increased risk in all but one. There were significant decreases in triglycerides and VLDL cholesterol and no significant change in LDL cholesterol. There was a significant reduction of 18% in HDL cholesterol and a 26% reduction in the HDL2:HDL3 ratio. Conclusion: The reduction in lipoprotein(a) levels may have a beneficial effect on cardiovascular risk, which could go some way towards balancing the potentially adverse effect on the cardiovascular system caused by the reduction in HDL cholesterol. 相似文献
67.
Carlo Caffarelli Carla Mastrorilli Angelica Santoro Massimo Criscione Michela Procaccianti 《Nutrients》2021,13(2)
Hazelnuts commonly elicit allergic reactions starting from childhood and adolescence, with a rare resolution over time. The definite diagnosis of a hazelnut allergy relies on an oral food challenge. The role of component resolved diagnostics in reducing the need for oral food challenges in the diagnosis of hazelnut allergies is still debated. Therefore, three electronic databases were systematically searched for studies on the diagnostic accuracy of specific-IgE (sIgE) on hazelnut proteins for identifying children with a hazelnut allergy. Studies regarding IgE testing on at least one hazelnut allergen component in children whose final diagnosis was determined by oral food challenges or a suggestive history of serious symptoms due to a hazelnut allergy were included. Study quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Eight studies enrolling 757 children, were identified. Overall, sensitivity, specificity, area under the curve and diagnostic odd ratio of Cor a 1 sIgE were lower than those of Cor a 9 and Cor a 14 sIge. When the test results were positive, the post-test probability of a hazelnut allergy was 34% for Cor a 1 sIgE, 60% for Cor a9 sIgE and 73% for Cor a 14 sIgE. When the test results were negative, the post-test probability of a hazelnut allergy was 55% for Cor a 1 sIgE, 16% for Cor a9 sIgE and 14% for Cor a 14 sIgE. Measurement of IgE levels to Cor a 9 and Cor a 14 might have the potential to improve specificity in detecting clinically tolerant children among hazelnut-sensitized ones, reducing the need to perform oral food challenges. 相似文献
68.
Xiaoyu Wang Mingzhen Zhang Regina R. Woloshun Yang Yu Jennifer K. Lee Shireen R. L. Flores Didier Merlin James F. Collins 《Nutrients》2021,13(5)
Intestinal iron transport requires an iron importer (Dmt1) and an iron exporter (Fpn1). The hormone hepcidin regulates iron absorption by modulating Fpn1 protein levels on the basolateral surface of duodenal enterocytes. In the genetic, iron-loading disorder hereditary hemochromatosis (HH), hepcidin production is low and Fpn1 protein expression is elevated. High Fpn1-mediated iron export depletes intracellular iron, causing a paradoxical increase in Dmt1-mediated iron import. Increased activity of both transporters causes excessive iron absorption, thus initiating body iron loading. Logically then, silencing of intestinal Dmt1 or Fpn1 could be an effective therapeutic intervention in HH. It was previously established that Dmt1 knock down prevented iron-loading in weanling Hamp (encoding hepcidin) KO mice (modeling type 2B HH). Here, we tested the hypothesis that Dmt1 silencing combined with dietary iron restriction (which may be recommended for HH patients) will mitigate iron loading once already established. Accordingly, adult Hamp KO mice were switched to a low-iron (LFe) diet and (non-toxic) folic acid-coupled, ginger nanoparticle-derived lipid vectors (FA-GDLVs) were used to deliver negative-control (NC) or Dmt1 siRNA by oral, intragastric gavage daily for 21 days. The LFe diet reduced body iron burden, and experimental interventions potentiated iron losses. For example, Dmt1 siRNA treatment suppressed duodenal Dmt1 mRNA expression (by ~50%) and reduced serum and liver non-heme iron levels (by ~60% and >85%, respectively). Interestingly, some iron-related parameters were repressed similarly by FA-GDLVs carrying either siRNA, including 59Fe (as FeCl3) absorption (~20% lower), pancreatic non-heme iron (reduced by ~65%), and serum ferritin (decreased 40–50%). Ginger may thus contain bioactive lipids that also influence iron homeostasis. In conclusion, the combinatorial approach of FA-GDLV and Dmt1 siRNA treatment, with dietary iron restriction, mitigated pre-existing iron overload in a murine model of HH. 相似文献
69.
目的研究血清脂蛋白a(1ipoprotein(a),LP(a))在脑梗死形成中的作用及意义.方法采用双抗体夹心法检测血清中LP(a)的浓度.结果脑梗死组(n=71)LP(a)浓度显著高于健康对照组(n=37),p<0.05.脑梗死组与健康对照组中不同性别,年龄组LP(a)水平无显著差异,p>0.05.脑梗死组中,有无糖尿病及高血压,LP(a)水平无显著差异,P>0.05.结论LP(a)是与遗传有关的血浆脂蛋白,血清LP(a)水平高低在估计脑梗死患病风险上有参考意义. 相似文献
70.
陈志鸿 《南通大学学报(哲学社会科学版)》2001,17(3):130-133
师资是一所高校最重要的资源 ,是高校实现人才培养、科学研究和社会服务三大功能的主体力量 ,也是一所高校在人才培养、科学创造与学术成就以及社会影响力等方面获得竞争优势的决定性因素。在新的历史时期 ,高等院校师资队伍建设的总体目标 ,是建设一支素质良好、结构优化、富有活力、具有创新能力的师资队伍。其具体措施是完善选人机制 ,优化教师资源配置 ;采取得力措施 ,优化教师队伍成才环境 ;建立激励机制 ,加强学科带头人和骨干教师队伍建设 ;强化竞争机制 ,实施和完善教师聘任制 ;强化教师培训 ,全面提高教师素质 ;加大投入 ,确保教师队伍建设落到实处 相似文献