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1.
目的 探讨缺氧缺血再灌注后海马神经元的存活机制。方法  5 6只SD 7日龄鼠随机分入假术对照组、缺氧缺血脑损伤 (HIBD)组。制备HIBD模型。多普勒监测动脉血流。免疫组织化学测磷酸化的CREB、c Jun在海马区的表达。Thionin染色观察神经元凋亡。结果 HIBD再灌注 3、2 4h仔鼠右侧海马各区p CREB达高峰 ,7d后降至对照组水平 ;对照组两侧p CREB有基础表达 ,但无差异。c Jun 6h达高峰 ,2 4h稍降 ,48h又升高 ,7d后显著降低 ,但仍显著高于对照组 (P <0 .0 1) ;对照组两侧低表达。再灌注 2 4h右侧海马CA1区神经元已有明显凋亡 ,但 7d后神经元无明显丢失。假手术组海马极少数神经元凋亡。结论 CREB磷酸化可能经信号转导调节c Jun的表达促进神经元损伤后修复。这对保护CA1区锥体神经元是非常重要的。  相似文献   

2.
新生鼠缺氧缺血再灌注后海马p-CREB c-fos表达的变化(英文)   总被引:1,自引:1,他引:0  
目的:探讨新生鼠脑缺氧缺血再灌注后的神经保护机制。方法:7d龄SD新生鼠7窝(每窝选用8只,共56只),随机分为假手术对照组、缺氧缺血脑损伤组。经弹性管穿线阻断右颈总动脉3h,低氧(8%O_2和92%N_2混合气)1h,制备HIBD模型。3h后剪开扎线予再灌注,彩色多普勒监测右侧颈总动脉血流。免疫组化检测磷酸化的CREB和c-fos在不同时间点(再灌注3h,6h,12h,24h,48h,72h和7d及假手术后24h)海马区的表达。Thionin染色观测神经元凋亡情况。结果:HIBD再灌注3h,24h新生鼠右侧海马p-CREB表达达高峰,7d后下降至假手术组水平;c-fos表达6h达高峰,24h稍降,48h又升高,7d后显著降低但仍高于对照组(P< 0.01)。Thionin染色发现:再灌注24h右侧海马CA1区已有明显的凋亡,但7d后神经元无明显丢失。结论:缺氧缺血再灌注后CREB磷酸化可能经信号转导调节c-fos的表达,这对保护损伤侧海马锥体神经元,尤其是敏感的CA1区神经元是非常重要的。[中国当代儿科杂志,2003,5(1):12-16]  相似文献   

3.
缺氧缺血再灌注后海马神经元凋亡与c-fos的表达   总被引:5,自引:2,他引:3  
目的 探讨新生鼠缺氧缺血再灌注后,机体神经保护机制与即刻早期基因c-fos表达的关系。方法7日龄SD鼠,经弹性管穿线阻断右颈总动脉3h,予低氧1h;制备成缺氧缺血脑损伤(HIBD)模型。后施以不同时期的再灌注,彩色多普勒监测血流阻断及再灌注情况。免疫组化观测c-fos在仔鼠HIBD后不同再灌注时间点海马的表达。Thionin染色及HE染色观测神经元的凋亡。结果 HIBD组右侧海马c-fos 6h达高峰,24h稍降,48h又升高,7d后显著降低但仍高于对照组(P<0.01)。对照组c-fos有极少数表达。凋亡检测发现:再灌注24h已有明显凋亡,7d后海马神经元未表现明显的丢失。结论c-fos可能参与HIBD后神经元的修复、存活过程;这对CA1区锥体神经元的存活非常重要。它可能经某些信号途径参与神经元的存活。  相似文献   

4.
目的探讨神经元的抗凋亡保护机制,评价环磷酸腺苷(cAMP)反应元件结合蛋白(CREB)、神经生长因子(NGF)对神经元损伤后的保护作用。方法7日龄Sprague-Dawley新生大鼠随机分为假手术组、缺氧缺血性脑损伤(HIBD)未治疗组、小干扰RNA(siRNA)治疗组、siRNA加NGF治疗组。按照改良的Rice法制备HIBD再灌注模型,各治疗组于再灌注后开始予1次siRNA干预治疗(10mg/kg);siRNA加NGF组予NGF(15μg/kg),1次/d。于治疗的不同时间通过免疫组织化学和Western blot法检测磷酸化的CREB、NGF在仔鼠HIBD再灌注后海马、丘脑神经元的表达变化。通过Thionine染色检测神经元凋亡。结果HIBD未治疗组3h仔鼠右侧海马CA1区磷酸化的CREB(p-CREB)表达达高峰,7d后降至假手术对照水平。3hNGF表达开始增加,12h持续达高峰,7d后仍明显高于假手术组(P〈0.05)。siRNA治疗组p-CREB与NGF表达随时间逐渐下降。HIBD再灌注未治疗组24h右侧海马CA1区已有明显的凋亡,7d神经元凋亡与假手术组相比无统计意义。siRNA治疗组神经元有大量的丢失;而siRNA加NGF治疗组神经元与假手术组比较无明显丢失。结论CREB经信号转导调节大鼠NGF的表达,从而促进其神经元损伤后修复,减少神经元死亡。  相似文献   

5.
缺氧缺血后新生鼠脑组织caspase-3mRNA表达变化及其意义   总被引:2,自引:0,他引:2  
目的 观察新生大鼠缺氧缺血后脑组织caspase 3mRNA表达动态变化 ,进一步探讨缺氧缺血诱导新生鼠神经元凋亡的机制及意义。方法 制备新生鼠HIBD模型 ,随机分为假手术对照组、HIBD 6h、2 4h、3d、5d组 ,每组 5只动物。应用RT PCR方法测定了大鼠脑组织caspase 3mRNA的表达。结果  7日龄Wistar大鼠假手术对照组即有一定水平caspase 3mRNA表达 ,HIBD 6h组表达增加(与对照组比较有显著性差异 ,P <0 0 5 ) ,HIBD 2 4h其表达呈高峰 ,此后逐渐下降 ,HIBD 5d仍维持较高水平 (与HIBD 6h相比有显著性差异 ,P <0 0 1)。结论 缺氧缺血可诱导新生鼠脑组织caspase 3mRNA表达 ,其过度表达在HIBD后神经元凋亡的调控中起一定作用 ,针对caspase 3的治疗对策为围生期缺氧缺血脑损伤打开了新视窗  相似文献   

6.
新近研究表明,c-AMP反应元件结合蛋白(c-AMP response element binding protein,CREB)磷酸化后所调控的基因转导可能是神经元再生存活的重要因素。为此,2001年8月至2002年3月我们采用免疫组化法检测磷酸化的CREB(p-CREB)、c-Fos在新生鼠缺氧缺血性脑损伤(HIBD)并再灌注不同时间点海马区表达情况,并结合神经元凋亡变  相似文献   

7.
目的 探讨亚低温对缺氧缺血脑损伤(HIBD)新生大鼠脑源性神经营养因子(BDNF)mRNA表达的影响.方法 新生7日龄Wistar大鼠84只,随机分为:假手术组(n=6),31 ℃亚低温干预组(n=36),非亚低温干预组(对照组,n=36)及正常对照组(n=6).于分组后6、12、24、48、72、96 h用原位杂交技术测定BDNF mRNA.用Tunel染色和免疫组化技术检测神经元凋亡数.结果 HIBD缺血再灌注后脑组织BDNFmRNA表达增加,亚低温组HIBD脑组织BDNFmRNA表达与未干预组比较差异有统计学意义,亚低温组脑组织海马、皮层区细胞凋亡数与未干预组比较差异有统计学意义.结论 亚低温可通过增加HIBD后脑组织海马、皮层BDNFmRNA的表达水平,抑制细胞凋亡而发挥脑保护作用.  相似文献   

8.
目的研究参附注射液对缺氧缺血性脑损伤(HIBD)新生大鼠海马神经元凋亡的影响。方法实验分成两部分:1.流式细胞术检测缺氧缺血(HI)前2 h、HI后2、12、24 h,3、7、14和28 d各时间点新生大鼠海马CA1区神经元凋亡率;2.免疫组织化学测HI前2 h、HI后2、12、24 h,3、7、14和28 d各时间点新生大鼠海马CA1区神经元Bcl-2、Bax蛋白表达。建立新生大鼠HIBD模型。每组实验随机分为4组:假手术组(S),9 g/L盐水对照组(C),参附预处理组(P),参附治疗组(SF)。结果SF和P组海马神经元凋亡情况明显低于C组(P〈0.01,〈0.05),且Bcl-2表达显著增多(P〈0.05,〈0.01),而Bax表达明显下调(P〈0.05,〈0.01)。结论参附注射液可明显上调新生大鼠HIBD后海马神经元Bcl-2蛋白表达,下调Bax蛋白表达,减少HIBD新生大鼠海马神经元凋亡发生。  相似文献   

9.
目的研究神经生长因子(NGF)对新生鼠缺氧缺血性脑损伤(HIBD)后,神经干细胞巢蛋白(nestin)及血管内皮生长因子(VEGF)表达的影响,探讨其神经修复作用机制。方法7日龄新生SD大鼠84只,建立HIBD模型后,随机分为假手术组、缺氧缺血组及NGF干预组各28只。神经生长因子干预组腹腔内注射NGF(6000U/kg/d),缺氧缺血组同步注射等量生理盐水。采用免疫组化法检测NGF对新生大鼠HIBD后不同时间内Nestin及VEGF表达的影响。结果缺氧缺血性脑损伤后12、24h,3、7、14d,NGF干预组在大脑皮质、海马和室旁区的Nestin表达高于缺氧缺血组(P<0.05),且高峰提前到3d。HIBD后即刻、3、12、24h及3d,NGF干预组在大脑皮质、海马区VEGF的表达高于缺氧缺血组(P<0.05),且高峰提前到3h。结论NGF对HIBD具有神经修复作用可能是通过上调nestin及VEGF的表达而实现的。  相似文献   

10.
目的 探讨新生大鼠缺氧缺血性脑损伤 (HIBD)后海马区血红素氧化酶 1(HO 1)的表达 ,以及与细胞凋亡的关系。方法  7日龄SD仔鼠 72只 ,随机分为HIBD组和假手术对照组。用原位杂交和免疫组化观测两组在不同时间点海马区HO 1mRNA及蛋白阳性细胞数量变化 ;用原位缺口末端标记 (TUNEL)法检测凋亡的脑细胞。结果  1.HIBD组右侧海马HO 1mRNA表达 4h开始升高 (P <0 .0 5 ) ,12h达高峰 ,4 8h开始略有下降 ,72h后仍高于对照组 (P <0 .0 1)。 2 .HO 1蛋白表达与HO 1mRNA表达变化规律相一致。 3.凋亡检测发现 ,HIBD组右侧海马 12h凋亡细胞数增加 ,2 4h已有明显细胞凋亡 (P <0 .0 1) ,72h凋亡细胞减少 ,仍高于对照组 (P <0 .0 5 )。结论 新生大鼠HIBD后HO 1mRNA及其蛋白表达增加 ,可能参与神经细胞凋亡  相似文献   

11.
There is a common progression known as the allergic march from atopic dermatitis to allergic asthma. Cetirizine has several antiallergic properties that suggest a potential effect on the development of airway inflammation and asthma in infants with atopic dermatitis. Methods. Over a two year period, 817 infants aged one to two years who suffered from atopic dermatitis and with a history of atopic disease in a parent or sibling were included in the ETAC® (Early Treatment of the Atopic Child) trial, a multi-country, double-blind, randomised, placebo-controlled trial. The infants were treated for 18 months with either cetirizine (0.25mg/ kg b.i.d.) or placebo. The number of infants who developed asthma was compared between the two groups. Clinical and biological assessments including analysis of total and specific IgE antibodies were performed. Results. In the placebo group, the relative risk (RR) for developing asthma was elevated in patients with a raised level of total IgE (≥ 30 kU/I) or specific IgE (≥ 0.35 kUA/I) for grass pollen, house dust mite or cat dander (RR between 1.4 and 1.7). Compared to placebo, cetirizine significantly reduced the incidence of asthma for patients sensitised to grass pollen (RR = 0.5) or to house dust mite (RR = 0.6). However, in the population that included all infants with normal and elevated total or specific IgE (intention-to-treat - ITT), there was no difference between the numbers of infants developing asthma while receiving cetirizine or placebo. The adverse events profile was similar in the two treatment groups. Discussion. Raised total IgE level and raised specific IgE levels to grass pollen, house dust mite or cat dander were predictive of subsequent asthma. Cetirizine halved the number of patients developing asthma in the subgroups sensitised to grass pollen or house dust mite (i.e. 20% of the study population). In view of the proven safety of the drug, we propose this treatment as a primary pharmacological intervention strategy to prevent the development of asthma in specifically sensitised infants with atopic dermatitis.  相似文献   

12.
孤独症谱系障碍(autistic-spectrum disorders,ASDs)近年来患病率逐年攀升至1%左右,其症状往往伴随终生,成为严重威胁儿童健康和发展的神经发育性疾患;注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)是儿童期最常见的精神障碍,国内报道患病率为4.13%~5.83%,其症状可延续至青少年期,甚至到成年期[1]。这两类精神障碍在成年期的临床表现、共患病、治疗策略和预后与儿童期有哪些不同呢?本文通过回顾相  相似文献   

13.
During the past several decades, our understanding of the complex pathophysiology of vasoocclusion associated with sickle cell disease has improved greatly. Interaction of genes, hemoglobin molecules, red cell membrane and metabolic changes, cell-cell interactions and cell-plasma interactions, red cell adhesion to vascular endothelium, activation of coagulation, and vascular reactivity play a role in vaso occlusion. Penicillin prophylaxis of pneumococcal infections and appropriate use of blood transfusions and other supportive measures improved survival of sickle cell patients. Hydroxyurea made a major impact on sickle cell therapy when it was shown to decrease acute painful episodes, acute chest syndrome, and the need for blood transfusion in adults. Significant experience in the use of hydroxyurea has been accumulated in older children. The benefits and risks of hydroxyurea for younger children and long-term risks in all patients will be evaluated in future investigations. Other promising therapies include butyrate compounds, clotrimazole, magnesium supplementation, poloxamer 188, antiadhesion agents, anticoagulant approaches, and nitric oxide. Hemopoietic transplantation remains the only curative therapy. However, several transgenic mouse models are available for studies of gene therapy or other treatment approaches on biochemical, cellular, and pathologic effects of mutant genes.  相似文献   

14.
A 21-year-old man with granular lymphocyte-proliferative disorders (GLPD) associated with chronic active Epstein-Barr virus (EBV) infection is described. Chromosomal analyses revealed several clonal abnormalities and two of them were mainly repetitious. High copy numbers of monoclonal EBV genome were also detected in the proliferative large granular lymphocytes (LGLs), indicating the monoclonal expansion of EBV-infected LGLs. The patient had an indolent course for several years, and there was no evidence of infiltrations of his bone marrow until the end stage. At autopsy, microscopic studies revealed marked infiltrations of LGL in the liver and spleen, and the infiltrating cells were NK-cell immunophenotype. The infiltrated LGLs showed latency I.  相似文献   

15.
Human male sexual development is regulated by chorionic gonadotropin (CG) and luteinizing hormone (LH). Aberrant sexual development caused by both activating and inactivating mutations of the human luteinizing hormone receptor (LHR) have been described. All known activating mutations of the LHR are missense mutations caused by single base substitution. The most common activating mutation is the replacement of Asp-578 by Gly due to the substitution of A by G at nucleotide position 1733. All activating mutations are present in exon 11 which encodes the transmembrane domain of the receptor. Constitutive activity of the LHR causes LH releasing hormone-independent precocious puberty in boys and the autosomal dominant disorder familial male-limited precocious puberty (FMPP). Both germline and somatic activating mutations of the LHR have been found in patients with testicular tumors. Activating mutations have no effect on females. The molecular genetics of the inactivating mutations of the LHR are more variable and include single base substitution, partial gene deletion, and insertion. These mutations are not localized and are present in both the extracellular and transmembrane domain of the receptor. Inactivation of the LHR gives rise to the autosomal recessive disorder Leydig cell hypoplasia (LCH) and male hypogonadism or male pseudohermaphroditism. Severity of the clinical phenotype in LCH patients correlates with the amount of residual activity of the mutated receptor. Females are less affected by inactivating mutation of the LHR. Symptoms caused by homozygous inactivating mutation of the LHR include polycystic ovaries and primary amenorrhea.  相似文献   

16.
17.
OBJECTIVE: To ascertain the profile of cases of measles seen at a general hospital during a recent outbreak that occurred despite a measles vaccination program. METHODOLOGY: A retrospective study from January 1991 to March 1998. All patients with measles (ICD code 055. 9) seen at the emergency unit or as inpatients were included. RESULTS: There were 87 cases identified. The diagnosis was clinical in all and proven serologically in 71%. Eighty-five per cent of the cases occurred between January 1997 and March 1998. There was a bi-modal age distribution with peaks in the very young (相似文献   

18.
The aim of the study was to explore psychological factors and autonomic activity in children with recurrent abdominal pain and to compare them with those in a control group of healthy children. The Personality Inventory for Children was used for assessment of developmental, emotional and psychosocial factors in 25 children with recurrent abdominal pain (age, 7-15 y). Parasympathetic and sympathetic functions in these children and in 23 healthy control subjects (age, 7-13 y) were also investigated, non-invasively using a computerized polygraph. Vagal tone (parasympathetic function) was indexed by calculation of respiratory sinus arrhythmia in beats/min. Skin conductance (sympathetic function) was recorded by the constant current method. On the Personality Inventory for Children, 16 patients had high scores on somatic concern. Several patients had scores in the clinical range for depression, withdrawal and anxiety, but the mean scores for these personality profile scales were well within the normal range of healthy children. Interestingly, there was a spike on the L (Lie)-scale for most of the patients and 15 patients had scores above or close to the clinical cut-off value. As compared with the scores in healthy children, vagal tone and sympathetic tone were normal. Conclusion: Many children with recurrent abdominal pain have scores in the clinical range for depression, withdrawal, anxiety and L-scale indicating coping problems, denial and a trend towards somatic concern that may contribute to the evolution of abdominal pain. Autonomic nerve activity was not disturbed in these children.  相似文献   

19.
Inhibition of the function of pulmonary surfactant in the alveolar space is an important element of the pathophysiology of many lung diseases, including meconium aspiration syndrome, pneumonia and acute respiratory distress syndrome. The known mechanisms by which surfactant dysfunction occurs are (a) competitive inhibition of phospholipid entry into the surface monolayer (e.g. by plasma proteins), and (b) infiltration and destabilization of the surface film by extraneous lipids (e.g. meconium-derived free fatty acids). Recent data suggest that addition of non-ionic polymers such as dextran and polyethylene glycol to surfactant mixtures may significantly improve resistance to inhibition. Polymers have been found to neutralize the effects of several different inhibitors, and can produce near-complete restoration of surfactant function. The anti-inhibitory properties of polymers, and their possible role as an adjunct to surfactant therapy, deserve further exploration.  相似文献   

20.
The World Health organisation recommends breast feeding infants for the first six months of life. When this breast feeding does not occur either through parental choice or medical need, infant formulas will be required. There is a bewildering array of formulas on the UK market for many different requirements. When faced with an unsettled infant many parents (and healthcare professionals) will experiment with the infant formula available and then attend the paediatric clinic looking for help and advice. It is therefore essential that paediatricians understand what milks are available and what the key differences between different products are. This review attempts to provide a simple guide through many of the formulations currently available in the UK; and offers advice for the dietary management of the child with extra calorie requirements, infants with cow's milk protein allergy, gastro oesophageal reflux disease, apparent unresolved hunger and infantile colic. Whatever the underlying condition, there is likely to be an infant formula that is suitable in this generation of ever expanding formulations.  相似文献   

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