环氧化酶-2在新生大鼠缺氧缺血性脑损伤的表达

目的探讨环氧化酶-2(COX-2)在新生儿缺氧缺血性脑损伤(HIBD)中的作用。方法新生7日龄大鼠制成HIBD模型,缺氧时间为2h,RT-PCR半定量分析COX-2mRNA,免疫组化方法测定COX-2蛋白表达,光镜下观察神经元坏死情况。结果HIBD后6、24、48h,5dCOX-2mRNA表达出现不同程度的表达增强,分别为(0·461±0·052),(0·887±0·0816),(0·660±0·119),(0·474±0·104),与对照组(0·321±0·175)比较,差异有统计学意义(P<0·01),其中HIBD24hCOX-2mRNA表达为最高峰,同其余各组相比,差异均有统计学意义(P<0·01),免疫组化结果与之一致。结论COX-2在新生儿HIBD形成中发挥一定的作用。     

新生大鼠缺氧缺血性脑损伤COX-2 mRNA表达变化

研究新生大鼠缺氧缺血性脑损伤(HIBD)时环氧合酶-2(COX-2)mRNA的表达变化,应用、制备新生大鼠左脑HIBD的模型.用逆转录多聚酶链反应(RT-PRC)检测HIBD后6 h、24h、48 h、5 d不同时点脑皮层COX-2 mRNA的表达情况.经凝胶成像及分析系统扫描RT-PCR产物,用内参半定量分析COX-2 mRNA的动态变化.结果显示七日龄Wistar大鼠对照组即有COX-2 mRNA的低表达,HIBD 6 h表达开始升高,HIBD 24～48 h为表达高峰(与对照组相比有显著性差异,P＜0.01),HIBD 5 d表达下降.结论新生大鼠HIBD可诱导COX-2基因表达,其可能参与HIBD后的神经毒性损伤.     

环氧化酶-2在新生大鼠缺氧缺血性脑损伤的表达及NS398抗凋亡作用

目的探讨环氧化酶-2(COX-2)在新生儿缺氧缺血性脑损伤(HIBD)中的作用及其抑制剂NS398抗凋亡作用。方法新生大鼠HIBD模型为研究对象,半定量RT-PCR检测脑组织COX-2mRNA,免疫组化方法测定COX-2蛋白表达,光镜下观察神经元坏死情况,TUNEL法测定NS398抗凋亡作用。结果HIBD后COX-2表达出现不同程度的增强,在HIBD24h达高峰,同其余各组表达量相比均有显著性差异(P<0.01)。缺氧前、后加入NS398,脑组织神经元凋亡程度有不同程度的降低,与对照组比较有显著性差异(P<0.01),缺氧前给药组神经元凋亡程度低于缺氧后给药组(P<0.01)。结论COX-2在新生儿HIBD形成中发挥重要的作用。NS398具有一定的抗凋亡作用,且早期给予COX-2特异性抑制剂NS398可能更好地发挥其抗凋亡作用。     

新生大鼠缺氧缺血性脑损伤COX-2mRNA表达变化

研究新生大鼠缺氧缺血性脑损伤(HIBD)时环氧合酶-2(COX-2)mRNA的表达变化,应用、制备新生大鼠左脑HIBD的模型。用逆转录多聚酶链反应(RT-PRC)检测HIBD后6 h、24h、48h、5d不同时点脑皮层COX-2 mRNA的表达情况。经凝胶成像及分析系统扫描RT-PCR产物,用内参半定量分析COX-2 mRNA的动态变化。结果显示:七日龄Wistar大鼠对照组即有COX-2 mRNA的低表达,HIBD 6h表达开始升高,HIBD 24～48h为表达高峰(与对照组相比有显著性差异,P<0.01),HIBD 5d表达下降。结论:新生大鼠HIBD可诱导COX-2基因表达,其可能参与HIBD后的神经毒性损伤。     

神经生长因子对缺氧缺血新生大鼠一氧化氮合成酶表达的影响

目的 探讨缺氧缺血(HI)后神经型一氧化氮合酶(nNOS)的变化及神经生长因子(NGF)对新生大鼠缺氧缺血性脑损伤(HIBD)的保护作用.方法 夹闭妊娠足月Wistar大鼠子宫血管,制成HIBD新生鼠模型.治疗组给予腹腔注射NGF4000 U/kg,1次/d,分别用1、3、7次.在生后不同时间检测nNOS表达、NO含量及细胞凋亡数量.结果 治疗组的NO含量明显降低,24 h的NO含量(μmol/L)为23.98±2.37,72 h为22.17±1.74,而HIBD组24 h和72 h的含量分别为31.64±3.23和30.31±1.76,两组比较,差异有统计学意义(P＜0.05);治疗组nNOS的表达也下降,24 h和72 h的表达量(个/mm2)为26.8±0.8和29.2±1.8,而同时间点HIBD组nNOS表达量为54.7±2.2和34.5±1.4,两组比较,差异有统计学意义(P＜0.05);神经细胞凋亡情况,治疗组72 h、7 d皮质和海马区的凋亡细胞数(个/mm2),分别为41.4±1.3、5.6±0.6和43.9±1.8、5.8±1.2,而HIBD组72 h、7 d皮质和海马区的凋亡细胞数分别为51.6±2.5、12.6±1.4和58.7±2.6、15.2±1.7,治疗组的凋亡细胞数明显降低,同时期同部位比较均有统计学意义(P＜0.05).结论 本研究证实NGF对新生大鼠HIBD有保护作用,通过抑制nNOS的表达,降低了炎性细胞因子NO的含量,减轻了HIBD后的脑细胞凋亡,证实NGF抗凋亡作用与抑制nNOS的表达从而减少NO生成有关.     

缺氧缺血新生大鼠脑组织caspase-1和白细胞介素18 mRNA表达及其关系探讨

目的研究caspase-1及其底物之一白细胞介素(IL)-18 mRNA的表达在缺氧缺血性脑损伤(HIBD)中的作用及其意义.方法 112只7日龄新生Wistar大鼠按照完全随机化方法分为对照组、HIBD 3、8、24 h、3、6和14 d组,每组16只.其中8只采用RT-PCR 方法检测caspase-1和IL-18 mRNA在HIBD后脑皮层中的表达及其相关性,另外8只光镜下观察脑组织病理学改变.结果对照组有caspase-1 mRNA少量表达(0.2918 ± 0.0809),HIBD 24 h组其水平开始增加(0.5222 ± 0.0941,与对照组比较P<0.01),6 d达高峰(0.7886 ± 0.0480,与其余各组相比P<0.01), 此后下降,但HIBD 14 d (0.5314 ± 0.1272)仍可检测出.对照组IL-18 mRNA水平为0.3218 ± 0.0466,HIBD 24 h至6 d其表达逐渐增加(24 h 0.5823 ± 0.0740; 3 d0.6976 ± 0.1073; 6 d 0.9110±0.0647,与对照组比较均为P<0.01),并达高峰(HIBD 6 d组与其余各组相比P<0.01).HIBD后IL-18 mRNA的表达在时间上与caspase-1具有紧密相关性(r=0.871,P<0.01).组织学检查发现神经元变性、坏死在HIBD 1～6天逐渐加重.结论 HIBD后caspase-1和IL-18 mRNA的表达逐渐增加,其变化规律与光镜观察到的脑损伤进展的时间框架吻合,提示它们均参与了新生鼠HIBD的病理形成过程.     

促红细胞生成素对缺氧缺血性脑损伤新生大鼠海马MMP-2表达的影响

目的探讨促红细胞生成素(EPO)对新生大鼠缺氧缺血性脑损伤(HIBD)后海马MMP-2表达的影响及其神经保护作用机制。方法将7日龄新生SD大鼠随机分为假手术组、缺氧缺血组(HIBD组)、EPO治疗组(EPO组),每组48只;各组大鼠分别在6 h、24 h、3 d、7 d时各处死12只。采用免疫组化及实时荧光定量PCR检测大鼠海马MMP-2蛋白及MMP-2 mRNA的表达。结果免疫组化结果显示,假手术组海马区MMP-2蛋白低水平表达,各时间点差异无统计学意义(P0.05);HIBD组及EPO组的MMP-2蛋白表达均呈增高趋势,且均在7 d时达高峰,每组各时间点的差异有统计学意义(P均0.05);除6 h外,三组间相同时间点MMP-2蛋白表达水平的差异有统计学意义(P均0.05),且7 d时EPO组与HIBD组的差异也有统计学意义(P0.05)。实时荧光定量PCR结果显示,假手术组MMP-2 mRNA呈增高趋势,但各时间点的差异无统计学意义(P0.05);HIBD组在24 h及7 d呈现双峰,且7 d峰值较24 h峰值高,但各时间点的差异无统计学意义(P0.05);EPO组则逐渐升高,各时间点的差异有统计学意义(P均0.05);在不同时间点,HIBD组及EPO组MMP-2mRNA均明显高于假手术组,差异有统计学意义(P均0.05);24 h时EPO组低于HIBD组,而7 d时则高于HIBD组,差异均有统计学意义(P0.05)。结论 EPO在HIBD恢复期上调MMP-2的表达,这可能是其对HIBD的神经保护作用机制之一。     

缺氧缺血性脑损伤新生大鼠脑神经细胞凋亡及脑组织中Rho GDP解离抑制因子和Bcl-2表达的变化

目的 研究Rho GDP解离抑制因子(Rho GDP dissociation inhibitor 2,RhoGDI2)mRNA 及Bcl-2 mRNA的表达在缺氧缺血性脑损伤(hypoxic-ischemic brain damage,HIBD)中的作用和机制.方法 30只新生7日龄SD大鼠按照完全随机化方法分为假手术组及HIBD 6 h和48 h组,每组10只.采用流式细胞仪检测脑细胞凋亡情况,并用Real-time RT-PCR方法测定脑组织中RhoGDI2和Bcl-2mRNA表达水平.结果 (1)新生大鼠HIBD后48h结扎侧大脑半球脑水肿明显.(2) HIBD6 h出现典型的凋亡细胞峰,细胞凋亡率为(1.40±0.12)％.HIBD 48 h凋亡峰更为明显,细胞凋亡率达到( 15.86±0.98)％.缺氧缺血后与假手术组相比,差异有统计学意义(P＜0.01).(3)假手术组大鼠RhoGDI2和Bcl-2 mRNA表达水平较高(4.12±0.74、2.55±0.65),在HIBD 6 h后二者表达开始下降(3.19±0.77、1.96±0.36),48 h降低更加明显(1.04±0.18、1.06±0.17),与假手术组比较,HIBD各时间点RhoGDI2和Bcl-2 mRNA的表达均明显降低,差异有统计学意义(P＜0.01).(4)缺氧缺m后各时间点RhoGDI2 mRNA的表达和Bcl-2 mRNA的表达呈正相关(r=0.831,P＜0.05).结论 脑缺氧缺血后,随着凋亡的出现,RhoGDI2和Bcl-2 mRNA表达水平降低,提示Rh0GDI2表达失衡可能通过Bcl-2参与新生大鼠HIBD中凋亡的发生.     

新生大鼠缺氧缺血性脑损伤后神经干细胞巢蛋白表达的变化

目的 了解神经干细胞巢蛋白(nestin)在新生大鼠缺氧缺血性脑损伤(HIBD)后表达的动态变化.方法 56只新生7日龄SD大鼠随机分为假手术组、缺氧缺血组.制备大鼠HIBD模型后分别于即刻、3、12、24 h,3、7、14 d将动物处死.采用SABC免疫组化方法检测nestin蛋白表达的动态变化.结果 假手术组nestin蛋白在海马、室管膜下区弱表达,在皮质几乎不表达,缺氧缺血组nestin蛋白12 h在皮质,24 h在海马、室管膜下区表达增加,nestin阳性细胞数分别为13.3±1.8,37.9±5.7,35.5±7.2,与假手术组相比有统计学差异,P＜0.05.皮质、海马、室管膜下nestin阳性细胞数均在7 d达高峰,分别为88.5±3.5,100.7±8.1,96.8±5.8,与假手术组相比有统计学差异,P＜0.05,在缺血14 d降低至假手术组水平.结论 新生大鼠缺氧缺血脑损伤后nestin蛋白表达增加,nestin的表达可能是神经干细胞增殖及胶质细胞反应共同作用的结果.     

缺氧缺血性脑损伤新生大鼠脑组织MMP-9和TIMP-1表达的动态变化研究

目的 探讨新生大鼠缺氧缺血性脑损伤(HIBD)的发生机制.方法 建立新生大鼠HIBD模型,随机分为假手术组及HIBD 6 h、12 h、24 h、48 h、72 h组,每组6只.观察脑组织大体病理学改变.采用Real-time Q-PCR方法测定大鼠脑组织MMP-9 mRNA和TIMP-1 mRNA表达.结果 (1)新生大鼠HIBD后12～48 h脑水肿明显,可见点状软化坏死灶.(2)假手术组大鼠MMP-9 mRNA表达水平极低,HIBD组大鼠在缺氧缺血6 h表达开始增高,24 h达高峰,此后渐渐下降,但72 h仍维持较高的水平,与假手术组相比差异有非常显著性(P＜0.01).(3)假手术组大鼠TIMP-1 mRNA表达水平极低,HIBD组大鼠在经历缺氧缺血6、12、24h,TIMP-1 mRNA表达水平有微弱升高,与假手术组相比差异有显著性(P＜0.05),但48 h后TIMP-1 mRNA表达下降到假手术组水平(P＞0.05).(4)MMP-9 mRNA/TIMP-1 mRNA比值在假手术组接近1:1,HIBD组缺氧缺血12 h后比值升高,在48 h达到高峰,72 h有所下降,但仍高于假手术组(P＜0.01).结论 新生大鼠HIBD后可诱导MMP-9 mRNA表达,而MMP-9 mRNA和TIMP-1 mRNA表达的失衡可能参与了HIBD的发病过程.     

Allergic factors associated with the development of asthma and the influence of cetirizine in a double-blind, randomised, placebo-controlled trial: First results of ETA®

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.     

Bibliometric data: a disaster for many non-American biomedical journals

Bibliometric data published by the Institute of Scientific Information in Philadelphia (ISI), and which was previously discussed in Acta Paediatrica , has increasingly been used despite all the relevant and severe criticism that has been raised against this method of evaluating individual research results and grading scientific journals. It is obvious that the present trend regarding the use of bibliometric data as a basis for priorities and funding of research and for the promotion of individual scientists favours American-oriented research projects at the expense of those that are based on concepts of predominantly European relevance.

Conclusion: For the future of non-American research, it is important that no single super-power, i.e. the USA, should dominate scientific priorities. The condition for efficient European competition is that European Centres with high levels of competence for creative research and training of scientists from all over the world are established. In addition, it is important that the results of European research are published in prestigious European journals, as was the situation before World War II.     

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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     

Infiltrations of Epstein-Barr virus-carrying cells in granular lymphocyte-proliferative disorders corresponding to chronic active Epstein-Barr virus infection

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.     

LUTEINIZING HORMONE RECEPTOR MUTATIONS IN DISORDERS OF SEXUAL DEVELOPMENT AND CANCER

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.     

EXCITING NEW TREATMENT APPROACHES FOR PATHYPHYSIOLOGIC MECHANISMS OF SICKLE CELL DISEASE

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.     

Personality profiles and heart rate variability (vagal tone) in children with recurrent abdominal pain

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.     

Understanding infant formula

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.     

alpha -SMOOTH MUSCLE ACTIN DISTRIBUTION IN THE PULMONARY VASCULATURE COMPARING HYPOPLASTIC AND NORMAL FETAL LUNGS

We investigated the intra-acinar pulmonary vascular muscularization in the developing human fetal lung between the 17th and 24th gestational weeks, that is, during the canalicular phase of lung development. Fifteen hypoplastic and 25 normal developed lungs were included in this study using monoclonal alpha -smooth muscle (sm) actin antibodies for smooth muscle detection. Computer-aided image analysis was performed for morphometrical measurements and statistical evaluation. Alphasm-actin-immunoreactive intra-acinar vessels down to a luminal diameter of less than 10 mu m were detected in hypoplastic as well as in normally developed lungs. Crucial differences presented as follows: significantly higher density of intra-acinar vessels, especially due to alpha -sm-actin-negative vessels less than 30 mu m in luminal diameter, in the control group; significantly higher alpha -sm-actin immunoreactivity per section unit as well as per vessel in the hypoplastic lung group. As suggested by others, alpha-sm-actin-positive cells of the intra-acinar vessel wall in the developing human lung were demonstrated to be smooth muscle cells, their immediate precursors, and pericytes. We conclude that the increased alpha -sm-actin immunoreactivity represents muscularization of the vessel wall in functional terms and may be regarded as one structural cause among others for the establishment of persistent fetal circulation in hypoplastic lungs.