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11.
12.
【目的】本研究旨在建立一种简单快捷的炭疽水肿因子(EF)重组表达及纯化方法。【方法】构建GST-EF融合表达载体,基于EF基因的密码子使用偏好,选择菌株Escherichia coli BL21-Codon Plus(DE3)-RIL为表达宿主,对EF进行诱导表达;细胞透性技术分离粗蛋白,进而利用亲和层析一步法纯化EF;Native-PAGE、竞争性抑制实验及c AMP浓度分析用于鉴定EF的生物活性。【结果】实现了EF可溶性高效表达,透性化处理可有效抽提可溶性重组蛋白;利用亲和层析一步法纯化得到了纯度达96%的EF;EF可与保护性抗原(PA)结合形成水肿毒素,该毒素能够急剧提高CHO-K1细胞中c AMP的浓度。【结论】本研究建立了一种高效快速制备具有生物活性的炭疽水肿因子的方法,为炭疽相关研究工作提供了新的选择。 相似文献
13.
张道远 《基因组学与应用生物学》2019,(2):859-864
为了探讨2型糖尿病白内障术后黄斑水肿与房水中细胞因子的关系,本研究选取2016年2月至2017年7月在我院治疗的2型糖尿病白内障患者117例117眼,均行超声乳化白内障摘除术,观察术后4周黄斑水肿发生情况以及房水中多种细胞因子水平。研究结果显示:术后4周,有37眼发生黄斑水肿(观察组),未发生黄斑水肿80眼(对照组);观察组术后4周黄斑区视网膜厚度为(247.28±18.37)μm,明显高于对照组(p<0.05),且明显高于术前水平(p<0.05);观察组术后4周干扰素诱导蛋白-10 (IP-10)、巨噬细胞趋化蛋白(MCP-1)、血管内皮生长因子(VEGF)和细胞因子转化生长因子-β2 (TGF-β2)水平分别为(6.01±0.89) pg/mL、(340.03±45.39) pg/mL、(812.28±40.06) pg/mL和(40.05±10.03) pg/mL,明显高于对照组(p<0.05),且高于术前水平(p<0.05);观察组和对照组手术前后粒细胞-巨噬细胞集落刺激因子(GM-CSF)和碱性成纤维细胞生长因子(b-FGF)比较差异无统计学意义(p>0.05);术后4周IP-10、MCP-1、VEGF和TGF-β2水平与黄斑区视网膜厚度呈正相关(r=0.452, 0.501, 0.466和0.470, p<0.05)。本研究的结果初步说明,房水中IP-10、MCP-1、VEGF和TGF-2水平与2型糖尿病白内障术后黄斑水肿有一定关系,有可能成为黄斑水肿的特异性评价指标,值得进一步研究。 相似文献
14.
Summary. The possibility that nitric oxide synthase (NOS) inhibitors influence dynorphin immunoreactivity following hyperthermia was
examined in a rat model using a pharmacological approach. Previous reports from our laboratory show that hyperthermia induces
an upregulation of NOS in several brain regions that seems to be instrumental in causing cell injury. Recent reports suggest
that nitric oxide (NO) can influence dynorphin neurotransmission in the normal brain as well as in several pathological states.
Since dynorphin is neurotoxic in different animal models of brain or spinal cord injury, it may be that the peptide will contribute
to the cell injury in hyperthermia. The present investigation was carried out to determine whether hyperthermia can influence
dynorphin immunoreactivity in the brain, and if so, whether inhibition of NOS will influence the peptide distribution in the
brain following heat stress. Rats subjected to hyperthermia at 38°C for 4 h in a biological oxygen demand incubator (BOD)
resulted in a marked upregulation of dynorphin immunoreactivity in several brain regions e.g., cerebral cortex, hippocampus,
cerebellum and brain stem. Pretreatment of rats with two potent NOS inhibitors, L-NAME (30 mg/kg/day, i.p. for 7 days) or
L-NMMA (35 mg/kg/day, i.p. for 7 days) significantly attenuated the dynorphin immunoreactivity in the brain. These drugs were
also able to reduce hyperthermia induced blood-brain barrier (BBB) permeability, brain edema formation and cell injury. Taken
together, our results suggest that (i) hyperthermia has the capacity to upregulate dynorphin immunoreactivity in the brain,
(ii) inhibition of NOS considerably attenuates the dynorphin immunoreaction following heat stress and (iii) upregulation of
dynorphin is somehow contributing to hyperthermia induced brain damage, not reported earlier.
Received July 3, 2001 Accepted August 6, 2001 Published online July 31, 2002 相似文献
15.
Mraovitch S 《Cellular and molecular neurobiology》2003,23(4-5):773-791
1. Generalized convulsive seizures can be elicited by a single unilateral microinjection of the cholinergic muscarinic agonist, carbachol, into the specific sites of the thalamus including ventral posterolateral and the reticular thalamic nuclei. The implication of the thalamic specific and reticular neurons is reviewed and discussed.2. On the basis of the c-fos regional expression and well-known efferent and afferent pathways linking these regions, a neuronal network relating the limbic, thalamo–striatal–cortical, and central autonomic systems, was constructed.3. The pattern of Fos immunoreactivity associated with long-lasting isocortical vasodilatation elicited by generalized convulsive seizures in anesthetized rat following cholinergic stimulation of the thalamus can be attributed to both the electrocortical activity and the long-lasting increase in cortical blood flow. We propose that the sustained cerebral cortical blood flow response during convulsive epileptic seizures may implicate intracerebral vasodilatory and vasoconstrictory neural mechanisms. Double-labeled NADPH-d and Fos-positive neurons implicated in maintaining the sustained isocortical vasodilatory response were found in the anterior lateral hypothalamic area. Inhibition of these neurons prevented the increase in cortical blood flow despite an increased metabolic demand manifested by the ictal electrocortical activity.4. Medial temporal lobe atrophy, including hippocampus, amygdala, and parahippocampal gyrus (piriform and entorhinal cortices) are the most common pathology in man. However the origin of medial lobe atrophy remain uncertain. Our results provide evidence that the allocortical microvascular inflammation may be in origin of the neurovascular degenerative processes leading to atrophy. 相似文献
16.
This study examines the contribution of anion transporters to the swelling and intracellular acidification of glial cells from an extracellular lactacidosis, a condition well-known to accompany cerebral ischemia and traumatic brain injury. Suspended C6 glioma cells were exposed to lactacidosis in physiological or anion-depleted media, and different anion transport inhibitors were applied. Changes in cell volume and intracellular pH (pH(i)) were simultaneously quantified by flow cytometry. Extracellular lactacidosis (pH 6.2) led to an increase in cell volume to 125.1 +/- 2.5% of baseline within 60 min, whereas the pH(i) dropped from the physiological value of 7.13 +/- 0.05 to 6.32 +/- 0.03. Suspension in Cl(-)-free or HCO(3)(-)/CO(2)-free media or application of anion transport inhibitors [0.1 mM bumetanide or 0.5 mM 4, 4'-diisothio-cyanatostilbene-2,2'-disulfonic acid (DIDS)] did not affect cell volume during baseline conditions but significantly reduced cell swelling from lactacidosis. In addition, the Cl(-)-free or HCO(3)(-)/CO(2)-free media and DIDS attenuated intracellular acidosis on extracellular acidification. From these findings it is concluded that besides the known activation of the Na(+)/H(+) exchanger, activation of the Na(+)-independent Cl(-)/HCO(3)(-) exchanger and the Na(+)-K(+)-Cl(-) cotransporter contributes to acidosis-induced glial swelling and the intracellular acidification. Inhibition of these processes may be of interest for future strategies in the treatment of cytotoxic brain edema from cerebral ischemia or traumatic brain injury. 相似文献
17.
目的:研究Ghrelin对大鼠脑出血后脑水肿及脑组织中基质金属蛋白酶-9(MMP-9)表达的影响。方法:选取雄性SD大鼠80只,随机分为对照组(NC组)20只、假手术组(SHAM组)20只、脑出血组(ICH组)20只、Ghrelin治疗组(Ghrelin组)20只。利用自体动脉血注入法建立大鼠脑出血模型;Ghrelin组于建立脑出血模型后经股静脉注射Ghrelin 10 nmol/Kg·d。分别于12 h、24 h、3d、5 d、7 d时间点根据Berderson评分法评估各组大鼠神经系统功能;利用干湿重法测定各组大鼠脑组织含水量;利用蛋白质免疫印迹法(WB)检测脑组织中MMP-9表达情况。结果:在12 h、24 h、3 d、5 d、7 d,ICH组、Ghrelin组大鼠Berderson评分及脑组织含水量高于NC组、SHAM组(P0.05);在5 d、7 d,ICH组大鼠Berderson评分及脑组织含水量高于Ghrelin组(P0.05)。WB结果表明在12 h、24 h、3 d、5 d、7 d,ICH组大鼠脑组织中MMP-9的表达均高于NC组、SHAM组(P0.05);Ghrelin组MMP-9的表达在12 h、24 h、3 d高于NC组、SHAM组(P0.05),在5 d、7 d,与NC组、SHAM组无明显差异(P0.05);在5 d、7 d,ICH组MMP-9表达高于Ghrelin组(P0.05)。结论:在本研究中,Ghrelin可以在5 d后降低脑出血大鼠脑组织中MMP-9的表达程度,从而减轻脑水肿,改善脑出血大鼠神经功能。 相似文献
18.
A review and update of animal toxicoses associated with fumonisin-contaminated feeds and production of fumonisins by Fusarium isolates 总被引:6,自引:0,他引:6
P. Frank Ross Larry G. Rice Gary D. Osweiler Paul E. Nelson John L. Richard Terrance M. Wilson 《Mycopathologia》1992,117(1-2):109-114
During the 1989 corn harvest season, numerous reports of equine leukoencephalomalacia (ELEM) outbreaks and a pulmonary edema (PPE) syndrome in swine from several regions of the United States were received by the National Veterinary Services Laboratories (NVSL), Ames, Iowa. Previous and concurrent research linked Fusarium moniliforme and fumonisin-contaminated feeds to both diseases. Chemical and mycological investigations revealed fumonisin B1 (FB1) concentrations of 20 to 360 ppm in suspect swine feeds and 8 to 117 ppm in suspect equine feeds. Nonproblem feeds contained concentrations below 8 ppm. Fusarium moniliforme and Fusarium proliferatum were isolated from both problem and nonproblem equine and swine feeds. When cultured on autoclaved corn, the F. moniliforme and F. proliferatum isolates produced respective FB1 and fumonisin B2 (FB2) that range from less than 5 to more than 2450 ppm and less than 5 to more than 1000 ppm, respectively. Isolates from both problem and nonproblem feeds produced high levels (greater than 500 ppm) in culture. Reported here is a review of chemical and mycological data resulting from the study of several cases of PPE and ELEM. 相似文献
19.
Tian-Yu Liang Li-Hai Lu Si-Yu Tang Zi-Hao Zheng Kai Shi Jing-Quan Liu 《World journal of stem cells》2023,15(4):150-164
Acute respiratory distress syndrome (ARDS) is a common and clinically devastating disease that causes respiratory failure. Morbidity and mortality of patients in intensive care units are stubbornly high, and various complications severely affect the quality of life of survivors. The pathophysiology of ARDS includes increased alveolar–capillary membrane permeability, an influx of protein-rich pulmonary edema fluid, and surfactant dysfunction leading to severe hypoxemia. At present, the main treatment for ARDS is mechanical treatment combined with diuretics to reduce pulmonary edema, which primarily improves symptoms, but the prognosis of patients with ARDS is still very poor. Mesen chymal stem cells (MSCs) are stromal cells that possess the capacity to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as the umbilical cord, endometrial polyps, menstrual blood, bone marrow, and adipose tissues. Studies have confirmed the critical healing and immunomodulatory properties of MSCs in the treatment of a variety of diseases. Recently, the potential of stem cells in treating ARDS has been explored via basic research and clinical trials. The efficacy of MSCs has been shown in a variety of in vivo models of ARDS, reducing bacterial pneumonia and ischemia-reperfusion injury while promoting the repair of ventilator-induced lung injury. This article reviews the current basic research findings and clinical applications of MSCs in the treatment of ARDS in order to emphasize the clinical prospects of MSCs. 相似文献
20.