儿童MELAS综合征临床及分子遗传学特点分析

目的　探讨线粒体脑病伴乳酸酸中毒和卒中样发作综合征 (MELAS综合征 )临床及分子遗传学特点。方法　对北京大学第一医院儿科 1998～ 2 0 0 3年收治的 8例MELAS综合征患儿临床表现、一般实验室检查、肌肉病理及线粒体DNA32 4 3位点点突变检测结果进行分析。结果　 ( 1)临床特点 :早期智力运动发育里程碑基本正常 ;多数患儿身材矮小伴多毛 ;6例肌肉受累 ;中枢神经系统症状出现年龄 3～ 13岁 ,其中发作性头痛 5例 ,偏瘫、视力障碍、智力倒退各 4例 ,惊厥 7例。 ( 2 )实验室检查 :6例静态乳酸、丙酮酸升高 ;5例行血气分析仅 1例示代谢性酸中毒 ;肌酸肌酶均正常 ;3例行肌电图仅 1例异常 ;7例行肌活检均见异常线粒体堆积 ;脑电图均示背景慢波增多 ;头颅MRI示 5例枕部异常信号 ,5例双基底节异常信号 ;1例脑干及小脑异常信号 ;1例小脑萎缩伴轻度大脑皮层萎缩 ;1例未见异常。 ( 3)分子遗传学 :5例白细胞线粒体DNA存在 32 4 3位点A→G突变 ,突变率为 37%～6 0 % ,其中 1例母亲存在同样突变。结论　MELAS综合征的临床表现多样 ,血乳酸丙酮酸、肌肉病理、头颅MRI及分子遗传学检查对于诊断此病尤为重要     

线粒体脑肌病伴乳酸血症和卒中样发作综合征的临床特征及遗传学研究

目的探讨线粒体脑肌病伴乳酸血症和卒中样发作（MELAS）综合征临床与分子遗传学特征，寻找MELAS线粒体DNA（mtDNA）A3243G点突变比例与临床特征的关联性。方法对2001年1月至2008年1月在首都医科大学附属北京儿童医院神经内科住院和门诊临床疑似线粒体脑肌病的患儿，行外周血白细胞mtDNA A3243G点突变筛查、血乳酸检测和神经影像学等检查。A3243G点突变阳性病例中选取符合MELAS临床疑似诊断标准的患儿（突变阳性组），对其家系进行调查，采集家族成员血进行mtDNA A3243G点突变筛查；A3243G点突变阴性病例中选取符合MELAS临床疑似诊断标准的患儿行肌肉病理活检和肌肉A3243G点突变筛查（突变阴性组）。分析比较两组的临床资料及MELAS遗传学特征。结果 研究期间共有272例疑似线粒体脑肌病的患儿进行了外周血白细胞A3243G点突变的筛查。A3243G点突变的20例阳性标本中，突变均为异胞质性（heteroplasmy），18例符合MELAS的临床疑似诊断标准。血细胞中突变型mtDNA的比例为9.0%～50.0%，其中4例同时在肌肉组织检测到相同突变，突变比例为42.4%～64.8%。临床症状以惊厥、乏力、智力进行性倒退、发热、呕吐、视力障碍和失语为主，身材矮小和体毛增多为主要体征，13例合并癫，血乳酸均升高，头颅CT/MRI显示双侧对称性苍白球钙化和脑梗死信号。A3243G点突变筛查阴性标本中有4例临床符合MELAS临床疑似诊断标准，肌肉病理可见破碎红边纤维，肌肉A3243G点突变筛查阴性。14个家庭中的37名家庭成员采集了外周血进行mtDNA A3243G点突变筛查，突变阳性组中患儿母亲5名检测到A3243G点突变，突变比例分别为3.0％，5.0%，11.8%，21.3% 和26.9%，同胞兄弟4名检测到A3243G突变，突变比例分别为19.3％、33.3%，37.5％和41.5%，均无临床症状，其他成员未检测到突变。本研究A3243G点突变比例与发病年龄和就诊年龄呈负相关趋势，与病程未见相关性。结论MELAS综合征的临床表现复杂多样，线粒体A3243G点突变是我国儿童MELAS最常见的突变，母系遗传为主。突变比例与年龄有相关趋势，与病程未见相关，血A3243G突变检查不能代替肌肉病理诊断。     

同胞同患Leigh综合征2例报告

Leigh综合征(Leigh syndrome,LS),又称亚急性坏死性脑脊髓病(subacute necrotizing encephalomyelopathy),属线粒体脑肌病的一种。由于临床症状复杂,病理检查取材困难,分子遗传学检测尚未普及,故诊断比较困难,临床医师对此病认识不足。现总结了2例同胞姐妹同患Leigh综合征病例,根据典型临床症状、体征、生化及头颅核磁共振成像(MRI)检查结果,可作出此病正确临床诊断。     

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1资料与方法1.1一般资料收集2001-01—2006-01于我院心内科就诊的室性早搏患儿77例,其中男42例,女35例,就诊前病程数小时至6年不等。病前有病毒感染史,并符合昆明会议制定的心肌炎诊断标准的27例,为心肌炎组;因呼吸道、胃肠道等感染就诊经心电图检查有室性早搏,余各项实验室检查均正常,20例患儿无自觉症状为疑似心肌炎组;学校或医院常规体格检查发现室性早搏,经查体及辅助检查,除室性早搏外未发现明确心脏病的30例患儿为单纯室性早搏组。1.2方法所有患儿入院均行十二导联心电图、24h动态心电图、超声心动图、心肌酶谱、心肌钙蛋白、柯萨奇病…     

小儿脓毒性休克并发心脏损害的回顾性分析

目的探讨小儿脓毒性休克并发心脏损害的临床特点及心肌酶谱、心电图和超声心动图改变。方法对2003年1月～2006年6月在我院PICU接受监护治疗的38例脓毒性休克并发心脏损害患儿的临床资料及心肌酶谱、心电图和超声心动图检查结果作系统回顾性分析。结果本组患儿临床诊断心力衰竭16例,死亡20例。38例患儿肌酸激酶和肌酸激酶同工酶均超过正常参考值上限。作心电图检查的35例患儿中,ST-T改变16例,异位心律9例,传导阻滞4例。作超声检查的19例患儿中,心脏收缩和(或)舒张功能下降6例,整个室壁运动异常6例,节段性室壁运动异常3例,前间隔中段运动减弱1例,射血分数<50%5例,缩短分数<20%4例,心脏增大5例。结论小儿脓毒性休克可导致心肌酶学、心脏电生理、心脏功能及形态改变。     

儿童线粒体脑肌病伴高乳酸血症和卒中样发作综合征2例报告

目的：探讨线粒体脑肌病伴高乳酸血症和卒中样发作综合征(MELAS)的诊断与治疗。方法回顾性分析2例MELAS患儿的临床特征及诊疗过程。结果2例患儿主要临床表现为卒中样发作、抽搐、视物模糊、高乳酸血症；发作期头颅磁共振成像结果符合典型的MELAS综合征影像学表现；基因测序存在mtDNA的A3243G点突变；改善供能及皮质激素治疗后症状明显改善。结论 MELAS临床症状复杂多样，血乳酸及头颅磁共振成像检查有助临床诊断，确诊需要肌肉活检或基因检测，皮质激素治疗有效。     

Leigh综合征的临床和分子遗传学研究进展

Leigh综合征又称亚急性坏死性脑脊髓病,是线粒体病中的常见类型,因线粒体能量产生障碍导致中枢神经系统进行性退行性损害。自1951年英国神经科学家Leigh首次报告以来,国内外在本症的病因、发病机制、临床诊断与治疗,以及分子遗传学方面逐渐有了新的认识。     

川崎病冠状动脉损害超声心动图及心电图分析

目的　探讨超声心动图与心电图对川崎病冠状动脉损害的诊断价值。方法　对川崎病患儿 78例行超声心动图及心电图检查 ,根据超声检查结果分为 3组 ,并对各组进行分析。结果　超声检出冠状动脉病变 45例 ,其中冠状动脉扩张 32例 ,冠状动脉瘤 1 3例 ;心电图异常 1 6例。冠状动脉损害组心电图异常率高于无冠状动脉损害组 (P <0 .0 1 ) ;冠状动脉瘤组心电图异常率明显高于冠状动脉扩张组 (P <0 .0 0 5)。结论　超声心动图与心电图相结合可更全面地反映川崎病的冠状动脉损害。     

以癫痫持续状态起病的线粒体脑肌病伴乳酸血症和卒中样发作患儿临床特点

目的探讨线粒体脑肌病合并乳酸血症与卒中样发作(MELAS)出现癫痫持续状态患儿的临床特点及治疗。方法回顾性分析4例以癫痫持续状态起病并最终确诊为MEILAS患儿的临床、脑电图、影像学及治疗。结果 4例患儿均以癫痫持续状态起病,血清乳酸、血氨、心肌酶升高,血钠降低,伴代谢性酸中毒;发作期及发作间期脑电图均有相应表现;头颅影像学发现基底节钙化、脑萎缩,急性期可见皮层水肿;基因检测提示mtDNA3243位点突变。结论 MELAS的癫痫发作较难控制,应尽早诊断,选择合适的抗癫痫药物及相关对症治疗,以减轻脑损伤。     

急性豆角中毒患儿血清心肌酶谱检测及临床意义

目的 了解急性豆角中毒患儿心肌损害情况.方法 以54例急性豆角中毒患儿为研究对象,根据症状轻重分成2组(轻症组24例,重症组30例),均于中毒后第3天晨起空腹抽静脉血,进行心肌酶谱检测.同时2组患儿均常规进行心电图检查.结果 轻症组血清乳酸脱氢酶(LDH)异常率为54.1%,肌酸激酶(CK)异常率为12.5%,CK-MB异常率为4.2%;而重症组血清LDH异常率为83.4%,CK异常率为55.3%,CK-MB异常率为33.3%;重症组LDH、CK、CK-MB异常率均显著高于轻症组(P＜0.05).结论 救治急性豆角中毒患儿时不能忽视心肌损伤.患儿心肌损害程度与中毒程度有关,心肌酶谱检测和心电图检查可辅助诊断.     

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.