首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
目的 探讨谷氨酰胺(glutamine,Gln)对新生鼠坏死性小肠结肠炎(necrotizing enterocolitis,NEC)肠黏膜修复的影响.方法 新生1日龄Wistar大鼠30只随机分为三组,A组为正常对照组;B组为NEC模型组;C组为NEC模型后灌胃给Gln组(2.0 g/kg·d).建立NEC模型,连续3天给予新生鼠100%二氧化碳5 min,然后再给予100%氧气5 min,放回母鼠身边喂养,第4天断头处死新生鼠,取肠道组织待检.分别取近回盲段2~3 cm肠道组织固定、包埋、切片.HE染色光镜下作病理学检查,应用免疫组化技术检测肠黏膜增殖细胞核抗原(PCNA)表达情况,原位末端标记(TUNEL)法检测肠黏膜细胞凋亡的变化.结果 B组HE染色切片见肠壁有不同程度的损伤,病理评分的中位积分为3分;C组有的肠黏膜正常,有的轻度肠上皮细胞脱落,有的绒毛轻度坏死,病理评分的中位积分为1分.B组PCNA数量均低于A组及C组(P<0.01).B组的肠黏膜细胞凋亡的数量高于A组及C组(P<0.01).结论 NEC时,新生鼠肠黏膜受损,增殖减慢,细胞凋亡的数量增加;补充Gln可促进NEC新生鼠肠黏膜隐窝细胞增殖,减少肠黏膜细胞凋亡数量,使肠黏膜修复加快.  相似文献   

2.
目的探讨谷氨酰胺(Gln)和表皮生长因子(EGF)对新生鼠坏死性小肠结肠炎(NEC)肠黏膜修复的影响。方法新生1日龄Wistar大鼠40只随机分为4组,A组(正常对照组),B组(NEC模型组),C组(NEC Gln),D组(NEC EGF Gln)。建立NEC模型,4 d后分别取近回盲段2~3 cm肠道组织固定、包埋、切片。HE染色光镜下作病理学检查,应用免疫组织化学技术检测肠黏膜增殖细胞核抗原(PCNA)的表达,TUNEL法检测肠黏膜细胞凋亡。结果B组HE染色切片见肠黏膜损伤,病理评分的中位积分为3分;C、D组损伤程度较轻,病理评分的中位积分为1分。B组PCNA阳性细胞数低于A组(P<0.01);C、D组PCNA阳性细胞数高于B组(P<0.01);且D组PCNA阳性细胞数高于C组(P<0.05)。B组肠黏膜细胞凋亡数高于A组(P<0.01);C、D组肠黏膜细胞凋亡数低于B组(P<0.01);且D组肠黏膜细胞凋亡数低于C组(P<0.05)。结论NEC新生鼠肠黏膜受损,增殖减慢,细胞凋亡数增加;补充Gln和EGF可促进NEC新生鼠肠黏膜隐窝细胞的增殖,减少肠黏膜细胞的凋亡,加快肠黏膜修复。  相似文献   

3.
目的探讨谷氨酰胺(Gln)对坏死性小肠结肠炎(NEC)新生鼠肠道组织中增殖细胞核抗原(PCNA)表达的影响及其肠黏膜保护作用。方法将出生48 h的SD新生大鼠随机分成对照组、Gln组、NEC组,NEC Gln组4组,每组12只。对照组予鼠乳代乳品人工喂养;Gln组采用鼠乳代乳品加Gln喂养;NEC组鼠代乳品喂养并于每天早晚予缺氧及冷刺激,连续3 d,建立NEC模型;NEC Gln组在建立NEC模型的同时,给予鼠乳代乳品加Gln喂养。采用免疫组化法检测新生鼠肠道PCNA的表达。结果与对照组和Gln组相比,NEC组和NEC Gln组的一般情况较差、体质量负增长,肠黏膜细胞出现炎性浸润,肠黏膜充血水肿,固有层分离,重者可见肠绒毛脱落、消失。对照组、Gln组、NEC组和NEC Gln组的PCNA阳性表达指数分别为34.17±5.78、34.42±5.38、15.00±1.94、30.67±3.14,差异有统计学意义(H=24.32,P<0.001)。NEC组PCNA阳性表达指数分别低于对照组、Gln组和NEC Gln组,差异均有统计学意义(P’<0.008);对照组、Gln组和NEC Gln组之间差异无统计学意义(P’>0.008)。结论发生NEC时,PCNA表达量降低;补充Gln可上调PCNA的表达量,加快肠黏膜修复。  相似文献   

4.
目的 研究肠三叶因子(ITF)对坏死性小肠结肠炎(NEC)新生大鼠肠黏膜组织核因子-κB(NF-κB)表达的影响,探讨ITF是否对NEC具有保护作用及其在NEC发病机制中的作用.方法 新生鼠50只随机分为5组,每组10只,A组(正常对照组)不做处理;B组(ITF组)皮下注射ITF 0.2 mg;C组为NEC模型组;D组[NEC加9g/L盐水(NS)组]制备NEC模型后皮下注射NS;E组(NEC加ITF组)制备NEC模型后皮下注射ITF 0.2 mg,连续3 d.大鼠均于实验第4天处死.分别于其十二指肠、小肠近中远端及结肠近端和远端处取1~2 cm肠道组织固定、包埋、切片、HE染色行病理学检查及免疫组织化学染色观察NF-κB表达.结果 C、D组组织中NF-κB(p65)阳性表达较A、B及E组显著升高(Pa <0.01),E组与A、B组比较也有升高(Pa <0.01),且随NF-κB(p165)的激活有明显的核转移;病理切片示C、D组HE染色见肠肇损伤轻重不一,可见全肠黏膜绒毛坏死,病理评分2~4分;E组轻度肠上皮细胞脱落,顶端绒毛坏死,肠组织病理评分0~2分.结论 通过皮下注射ITF可减轻NEC新生大鼠肠道炎性反应,NF-κB通路参与了NEC的发病过程,ITF可能通过抑制NF-κB的活化保护NEC模型新生大鼠的肠黏膜.  相似文献   

5.
目的探讨肠三叶因子(ITF)对坏死性小肠结肠炎(NEC)新生大鼠肠黏膜组织IL-6水平的影响,分析ITF对NEC的保护作用机制。方法新生鼠32只随机分为4组,每组各8只,正常对照组(A组);NEC模型组(B组);NEC模型后予以皮下注射9g/L盐水0.2mL(C组);NEC模型后予以皮下注射ITF0.2mg(D组)。取近回盲部1-2cm肠道组织固定包埋、切片、HE染色做病理学检查,其他肠道组织制备组织匀浆取上清液检测IL-6水平。结果B、C组组织匀浆IL-6的水平较A、D组显著增高(Pa〈0.05,0.01),A与D组无明显差异(P〉0.05)。病理切片显示C、D组HE染色切片见肠壁损伤轻重不一,可见全肠黏膜绒毛坏死,病理评分的中位积分为3分;D组肠上皮细胞少量脱落,顶端绒毛坏死,病理评分的中位积分为1分。结论通过皮下注射ITF可减轻NEC后的肠道炎性反应。ITF有可能为治疗NEC提供新的方法。  相似文献   

6.
目的 探讨肠三叶因子(ITF)对坏死性小肠结肠炎(NEC)新生大鼠肠黏膜组织IL-1β水平的影响,分析ITF对NEC的保护作用.方法 50只新生鼠随机分为5组,每组10只:A组为正常对照组,未进行缺氧、低温处理和注射药物;B组为正常ITF组,予皮下注射ITF0.2 mg(0.2 mL);C组为NEC模型组,建立NEC模型后未予药物注射;D组为NEC加9 g/L盐水(NS)组,建立NEC模型后予皮下注射NS 0.2 mL;E组为NEC加ITF组,建立NEC模型后予皮下注射ITF0.2 mg(0.2 mL).第4天断头处死动物后取其回盲部肠组织1~2 cm固定、包埋,HE染色行病理学检查,其他肠道组织制备组织匀浆取上清液应用ELISA试剂盒榆测IL-1β水平.结果 病理切片示C、D组HE染色切片见肠壁损伤轻重不一,可见全肠黏膜绒毛坏死,病理组织学积分为2~4分,E组肠上皮细胞有少量脱落,顶端绒毛坏死,病理组织学积分为0~2分.C、D组组织匀浆IL-1β水平均较E组显著增高(Pa<0.01);E组与A、B组比较均无显著性差异(Pa >0.05).结论 ITF下可通过降低IL-1β的水平减轻NEC模型的肠道炎性反应,ITF有可能为NEC的治疗提供新方法.  相似文献   

7.
目的 利用PI3K的特异性抑制剂Wortmannin阻断PI3K/Akt细胞信号转导通路,观察ITF对新生鼠NEC模型caspase-3及caspase-9水平的影响,探讨ITF对NEC的保护作用机制.方法 建立NEC模型,对新生一日龄Wistar大鼠予100%氮气,1 min后放4℃冷环境中持续10min,每日2次,随后放回自制的保温箱内人工喂养,第四天处死,取肠组织待检.新生鼠50只随机分为5组,每组10只,A组为NEC模型后予以腹腔注射生理盐水0.2 ml;B组NEC模型后予以腹腔注射ITF0.2 mg;C组为NEC模型后腹腔内注射wortmannin(0.1 mg/kg);D组为NEC模型后腹腔内注射ITF+wortmannin;E组为正常对照组.取近回盲部1~2 cm肠道组织固定包埋、切片、HE染色做病理学检查,其他肠道组织制备组织匀浆取上清液应用ELISA试剂盒检测PI3K的含量及用分光光度法检测caspase-3/9的活性.结果 病理切片显示A组HE染色见肠壁损伤轻重不一,可见全肠黏膜绒毛坏死,病理评分中位积分3分;B组病变明显减轻,肠上皮细胞少量脱落,顶端绒毛坏死,病理评分中位积分1分;C、D组病理评分中位积分3分.A组组织匀浆中PI3K的含量(pg/ml)较E组略升高(P<0.05),与D组差异无统计学意义(P>0.05);B组PI3K表达水平较其他组显著升高(P<0.01);C组与E组比较显著降低,差异有统计学意义(P<0.01).Caspase-3及caspase-9活性在A组较B、E组明显升高,差异有统计学意义(P<0.01),C组更加明显升高(P<0.01),A、D组及B、E组之间,差异无统计学意义(P>0.05).结论 通过腹腔注射ITF可以减轻NEC后的肠道炎症反应,ITF有可能为治疗NEC提供新的方法 ;PI3K/Akt细胞信号转导通路参与了NEC发病过程,并起着信号转导作用.而ITF可能是通过激活PI3K/Akt信号转导途径来下调caspase-3/9的水平,从而保护新生Wistar大鼠NEC模型肠道损伤.  相似文献   

8.
目的 分析肠三叶因子(ITF)对坏死性小肠结肠炎(NEC)新生鼠肠黏膜组织Bim基因与Bcl-xl基因表达水平的影响,探讨ITF对NEC的保护作用机制.方法 采用简单随机法将30只新生鼠分为对照组、NEC组及ITF组,每组10只,对照组不作处理,NEC组建立NEC模型后予以腹腔注射生理盐水0.2ml;ITF组为NEC模型后予以腹腔注射ITF 0.2 mg.对切片行HE染色并作组织病理学检查及免疫组织化学法检测Bim基因与Bcl-xl基因表达,并进行图像分析.结果 病理切片显示NEC组肠壁损伤轻重不一,可见全肠黏膜绒毛坏死,病理组织学改变中位积分为3分;ITF组肠上皮细胞少量脱落,顶端绒毛坏死,病理组织学改变中位积分为1分;图像分析结果显示NEC组Bim基因表达(7.87±0.14)高于对照组(2.15±0.28)及ITF组(3.27±0.34),三组比较差异均有统计学意义(P<0.05);ITF组Bcl-xl基因表达(11.23±0.22)高于对照组(1.89±0.28)及NEC组(2.51±0.13),三组比较差异均有统计学意义(P<0.05).结论 通过腹腔注射ITF可减轻NEC大鼠的肠道损伤,而ITF可能通过改变Bim基因与Bcl-xl基因表达水平保护NEC大鼠肠道损伤.  相似文献   

9.
肠细胞凋亡在新生鼠坏死性小肠结肠炎肠损伤中动态变化   总被引:1,自引:0,他引:1  
目的动态观察新生大鼠坏死性小肠结肠炎(NEC)发病过程中肠细胞凋亡率变化及其与肠损伤关系。方法40只新生SD大鼠随机分成对照组(C)和模型组(M)。对照组8只;模型组32只,在出生48h开始给予鼠配方奶人工喂养,100%氮气缺氧90s,4℃冷刺激10min,每天2次,连续3d,建立新生大鼠NEC模型;模型组开始造模后24h(M24)、48h(M48)、72h(造模结束,M72)及造模结束后24h(M96)分别处死8只,留取肠管进行肠组织损伤评分和肠细胞凋亡率检测(流式细胞仪)。组织学评分≥2确定为NEC。各组随机选取1份回盲部近端小肠标本进行肠黏膜透射电镜检查。采用SPSS11.0统计学软件进行统计分析,α=0.05为显著性检验标准。结果透射电镜显示模型组大鼠肠黏膜出现大量凋亡细胞,形成凋亡小体。对照组、M24、M48、M72和M96肠组织损伤评分分别为(0.08±0.15)、(1.38±0.42)、(1.46±0.69)、(1.58±0.30)分和(3.33±0.59)分,肠细胞凋亡率分别为4.8%±2.9%、12.8%±6.3%、14.9%±5.5%、17.7%±5.5%和27.6%±9.9%。肠损伤程度与肠细胞凋亡率呈显著正相关(r凋亡率=0.853,P<0.01)。结论新生鼠肠细胞凋亡增加是NEC肠组织损伤起始事件;随时间延长,肠细胞凋亡增加程度进一步加重;肠细胞凋亡增加是造成新生鼠NEC肠道进行性损伤的病理基础。  相似文献   

10.
目的 动态观察新生大鼠坏死性小肠结肠炎(NEC)发病过程中肠细胞凋亡率变化及其与肠损伤关系.方法 40只新生SD大鼠随机分成对照组(C)和模型组(M).对照组8只;模型组32只,在出生48 h开始给予鼠配方奶人工喂养,100%氮气缺氧90 s,4℃冷刺激10 min,每天2次,连续3 d,建立新生大鼠NEC模型;模型组开始造模后24 h(M24)、48 h(M48)、72 h(造模结束,M72)及造模结束后24 h(M96)分别处死8只,留取肠管进行肠组织损伤评分和肠细胞凋亡率检测(流式细胞仪).组织学评分≥2确定为NEC.各组随机选取1份回盲部近端小肠标本进行肠黏膜透射电镜检查.采用SPSS 11.0统计学软件进行统计分析,α =0.05为显著性检验标准.结果 透射电镜显示模型组大鼠肠黏膜出现大量凋亡细胞,形成凋亡小体.对照组、M24、M48、M72和M96肠组织损伤评分分别为(0.08±0.15)、(1.38±0.42)、(1.46±0.69)、(1.58±0.30)分和(3.33±0.59)分,肠细胞凋亡率分别为4.8%±2.9%、12.8%±6.3%、14.9%±5.5%、17.7%±5.5%和27.6%±9.9%.肠损伤程度与肠细胞凋亡率呈显著正相关(r<凋亡率=0.853,P<0.01).结论 新生鼠肠细胞凋亡增加是NEC肠组织损伤起始事件;随时间延长,肠细胞凋亡增加程度进一步加重;肠细胞凋亡增加是造成新生鼠NEC肠道进行性损伤的病理基础.  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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号