Use of HLA marker associations and HLA haplotype linkage to estimate disease risks in families with gluten-sensitive enteropathy

Based on a two-locus, double recessive model, we derive formulas for the risks that relatives of individuals with gluten-sensitive enteropathy (GSE) will also develop the disease. The calculations take advantage of: the linkage between the HLA locus and one of the two proposed GSE loci, and the preferential association of the HLA-DR3 and DR7 alleles with the GSE disease allele that occupies the HLA-linked locus. We use Bayes' rule to quantitate the strength of the association between the GSE disease allele and the HLA marker allele. This method predicts that siblings of the proband have an overall 10% risk for GSE, which is consistent with observed family data. This predicted risk rises to 30% when siblings are HLA-identical to the proband (also consistent with observed data) or when the sibling has the DR3 allele in the HLA haplotypes not shared with the proband. In those populations where DR7 also is associated with GSE, siblings of probands have a 10% predicted risk for GSE when only one HLA haplotype is shared with the proband and DR7 is included in the unshared haplotype. Other DR alleles are associated with much lower disease risks. By separating individuals into high and low risk groups, HLA typing identifies those individuals who would benefit from further diagnostic procedures. This general strategy should be applicable to other multilocus, marker-associated diseases.     

Novel mutations, including the second most common in Japan, in the β-hexosaminidase α subunit gene, and a simple screening of Japanese patients with Tay-Sachs disease

Two novel mutations of the β-hexosaminidase α subunit gene were identified in Japanese patients with the infantile form of Tay-Sachs disease. One mutation was a one-base deletion at nt613C, which generated a stop codon at two codons downstream, in three unrelated patients. The other mutation was a one-base substitution of G-to-A at IVS 5, +1, which caused a splicing abnormality, in one patient. A missense mutation of R170W, which has already been reported in other ethnic groups, was also newly identified in one patient. In 1993, the most common mutation (IVS 5, −1G → T) in Japanese patients with Tay-Sachs disease was reported as the major mutation in Japan accounting for 80% of 56 mutant alleles from 28 unrelated patients. The deletion of nt613C was the second most common mutation, accounting for 5% of the mutant alleles. The previously reported mutation IVS 5, −1G → T and the nt613C deletion found in this study together accounted for 85% of the mutations causing Tay-Sachs disease among Japanese. Since these two mutations were located in or close to exon 6 and since they abolish Fok I (IVS 5, −1G → T) and Sfa NI (nt613C deletion) restriction sites, respectively, they were screened rapidly by single polymerase chain reaction followed by digestion with these enzymes. Received: November 10, 1998 / Accepted November 14, 1998     

Molecular typing of echovirus serotype 4 isolates

We report on clinical samples Stuttgart/97, Berlin/99 and Jasi/99 associated with aseptic meningitis. All three samples contained echovirus 4 (E4) but Stuttgart/97 was simultaneous infected with echovirus 30 (E30). The genetic relationship of the E4 strains was assessed using RT-PCR and direct sequencing of amplicons derived from the genomic region encoding the capsid protein VP1. The sequences have been compared with each other and with sequences of further E4 strains obtained from GenBank. The analysis confirms that sequences of recent isolates have drifted away from elderly strains over a longer period of time. Several amino acid changes in assumed antigenic sites of the VP1 gene may be sufficient to cause changes in antigenic specificity and therefore they may be a reason for failure of serological typing of some new antigenic E4 variants.     

A case of 46,XX,r(X) (p1q1) diagnosed by in situ hybridization

A small marker chromosome was identified as an X-derived ring chromosome by in situ hybridization with a biotinylated X-chromosome specific a-satellite DNA probe. This procedure clearly determined the chromosomal origin of the marker chromosome, which had been impossible to define by conventional cytogenetic techniques including high resolution banding.     

常见呼吸道病毒分子鉴别诊断技术的建立

目的 建立一种常见呼吸道感染病毒的快速检测方法,为尽早诊断、减少疾病的传播以及为临床提供良好的治疗依据.方法 采用液体芯片检测技术结合靶向多重RT-PCR技术建立可以同时检测13种呼吸道病原的检测技术.结果 该方法特异性方面检测13种常见呼吸道病毒没有交叉,标本的检出率为100%;灵敏度方面达到10e2-10e1（pfu/ml）.结论 该分子鉴别诊断可应用常见呼吸道病毒的检测,协助诊断病毒引起的病毒性呼吸道感染.     

Genome analysis of dengue type-1 virus isolated between 1990 and 2001 in Brazil reveals a remarkable conservation of the structural proteins but amino acid differences in the non-structural proteins

We have investigated the genetic diversity of dengue type-1 (DEN-1) virus in Brazil. The full nucleotide sequences of three DEN-1 virus isolated from DEN fever (DF) and DEN hemorrhagic fever patients in northeastern Brazil in 1997 (BR/97) and one from a DF patient in the south of Brazil in 2001 (BR/01) were compared to that of the reference strain BR/90 obtained in the city of Rio de Janeiro in 1990. Sequence analysis showed that the structural proteins were remarkably conserved between all isolates. A total of 27 amino acid changes occurred throughout the non-structural proteins. Among them, nine amino acid substitutions were specific of BR/97 and BR/01 isolates, indicating that in situ evolution of these strains had occurred. Within the BR/97 and BR/01 samples, some amino acid substitutions have been previously identified in DEN-1 virus strains sequenced so far, suggesting that recombination events might have occurred.     

大鼠急性肺栓塞后SMP-30表达下降及其对细胞凋亡的影响

目的：研究大鼠急性肺栓塞模型肺组织中衰老标记蛋白质30(SMP-30)的表达变化及其对Fas诱导的细胞凋亡的影响。方法:建立大鼠急性肺栓塞模型，分别在急性肺栓塞后1、8、24和48 h进行支气管肺泡灌洗，然后开胸取出肺组织。常规提取肺组织的总RNA和总蛋白，以正常组为对照，采取半定量RT-PCR的方法研究SMP-30在mRNA水平表达的变化；采用Western blotting方法进一步验证SMP-30在蛋白水平表达的变化；采用免疫组织化学方法检测大鼠肺组织中SMP-30以及肺泡巨噬细胞中IL-8在肺栓塞前后表达的变化及其组织分布情况；采用TUNEL法研究急性肺栓塞后组织细胞的凋亡情况；最后采用ELISA法检测急性肺栓塞后肺泡灌洗液中sFasL的浓度变化。结果:在大鼠急性肺栓塞后的不同时点，SMP-30的mRNA水平和蛋白水平均逐渐降低，在24和48 h下降最为明显。免疫组化研究表明SMP-30主要分布在支气管黏膜上皮细胞和肺泡上皮细胞，急性肺栓塞后SMP-30在上述细胞内的表达均明显降低。TUNEL染色发现随着SMP-30表达的降低，肺组织内出现明显的细胞凋亡现象，同时肺泡灌洗液中sFasL的浓度升高，肺泡巨噬细胞内IL-8的表达也明显升高。结论:大鼠急性肺栓塞后肺组织内SMP-30的表达明显降低，可能促进Fas－FasL细胞凋亡系统的活化。     

2001至2005年上海部分地区腹泻住院患儿诺若病毒分子临床流行病学研究

目的通过对上海地区腹泻住院患儿进行诺若病毒检测,对其流行株进行基因序列的测定,以了解诺若病毒在上海地区的流行特征,为该病原体所致腹泻的防治提供基础数据和理论依据。方法收集2001至2005年复旦大学附属儿科医院5岁以下腹泻住院患儿的粪便标本。首先进行轮状病毒的检测,在轮状病毒抗原阴性标本中,每隔8个标本按编号顺序行机械随机抽样,建立RT-PCR方法进行诺若病毒的检测。对PCR产物进行双向测序,测序结果通过Clustal W和Mega 4.1软件进行分析。结果研究期间共收集腹泻患儿粪便标本5534份,轮状病毒抗原阴性4084份,机械随机抽得484份用于诺若病毒检测,45/484份(9.3%)检测到诺若病毒。对诺若病毒感染季节分布和患儿年龄特点的分析表明,除4月和7月份未检测到诺若病毒外,其余各月份均检测到诺若病毒,其高发的月份是8至11月。5~6月也呈一个小高峰。77.8%(35/45)的患儿<2岁,其中6~11个月的患儿所占比例最高,达35.6%(16/45),<6个月的婴儿占20%(9/45)。GⅡ-4型是这5年间尤其是2003年之后的主要流行型别,2001至2002年尚存在其他的流行型别GⅡ-3和GⅡ-7...     

阳离子交换色谱柱上聚合血红蛋白研究

采用柱上聚合的方法制备血红蛋白溶液，解决传统血红蛋白聚合过程中由于戊二醛的活性过高导致平均分子量大、产物分子量分布宽的问题。该方法利用阳离子交换剂对修饰度（聚合度）小的血红蛋白吸附能力大的原理，使其在柱上富积，同时加入戊二醛进行聚合反应。结果表明该方法能比较有效地缩小聚合血红蛋白的分子量分布。     

Lipoblastoma and lipoblastomatosis in infancy and childhood: histopathologic, ultrastructural, and cytogenetic features

Lipoblastoma is a relatively rare tumor that occurs in infancy and early childhood and arises from embryonic white fat. Although a benign tumor, lipoblastomas tend to recur and may resemble myxoid liposarcoma. The authors report 26 cases over a 15-year period at Texas Children's Hospital. There was a slight female predilection (14F:12M). The most common symptom was a painless mass with or without increasing size. The trunk, extremities, head and neck, retroperitoneum, inguinal canal, peritoneal cavity, and lung were the tumor sites. Most tumors were circumscribed lipoblastomas and the minority were diffuse infiltrative lipoblastomatosis. Reexcision for residual or recurrent tumor was necessary more frequently in patients with lipoblastomatosis. Histopathologic examination and ultrastructural examination revealed cellular neoplasms composed of immature adipocytes with relatively well-defined septa, frequent lipoblasts, a fine vascular network, and often a myxoid appearance resembling myxoid liposarcoma. Cytogenetics was performed in 4 cases with chromosome 8q abnormality being most common. The major concern with lipoblastoma in children is to completely excise the tumor to avoid leaving residual tumor and to prevent recurrences. Confusion with myxoid liposarcoma, well-differentiated liposarcoma, and typical lipomas may occur. Although asymptomatic, lipoblastomas may cause dysfunction of other organ systems due to mass effect. Complete surgical excision with at least 2 years of follow-up is the preferred therapy.