Type 2 Gaucher Disease with Hydrops Fetalis in an Ashkenazi Jewish Family Resulting from a Novel Recombinant Allele and a Rare Splice Junction Mutation in the Glucocerebrosidase Locus

Gaucher disease, the deficiency of the lysosomal enzyme glucocerebrosidase (EC 3.2.1.45), is frequently encountered in the Ashkenazi Jewish population. Carrier screening for Gaucher disease by enzyme analysis performed during a routine pregnancy indicated that both Ashkenazi parents were carriers. Screening for four common Gaucher mutations was subsequently performed on fetal and parental DNA. None of the common Ashkenazi mutations were identified. However, when exons 9–11 were amplified and digested withNciI to detect the L444P mutation, it appeared that the mother and the fetus had an unusual allele and that the expected paternal allele was not present. When the fetal amniocytes were found to have less than 2% of the normal glucocerebrosidase activity and a fetal sonogram revealed hydrops fetalis, the pregnancy was terminated. The diagnosis of severe type 2 Gaucher disease was confirmed at autopsy. Ultrastructural studies of epidermis from the fetus revealed the characteristic disruption of lamellar bilayers, diagnostic for type 2 Gaucher disease. In subsequent studies of the fetal DNA, long-template polymerase chain reaction amplification revealed one appropriately sized band (6.5 kb) and one smaller (5.2 kb) band. Sequencing of the 5.2-kb fragment identified a novel fusion allele resulting from recombination between the glucocerebrosidase gene and its pseudogene beginning in intron 3. This fusion allele was inherited from the father. The result was confirmed by Southern blot analysis using the enzymeSstII. Sequencing of the 6.5-kb fragment identified a previously described, although rare, T-to-G splice junction mutation in intron 10 of the maternal allele, which introduced anNciI site. The couple had a subsequent pregnancy which was also found to be affected. This case study identifies a novel recombinant allele and an unusual splice junction mutation, and demonstrates that even in the Ashkenazi population, screening for common mutations may not accurately identify the most severe forms of the disease.     

糖尿病患者尿路感染病原菌分布及耐药性分析

目的探讨糖尿病患者合并尿路感染的病原菌分布和耐药性,指导临床合理应用抗生素。方法回顾性分析2003年1月￣2005年9月81例2型糖尿病合并尿路感染患者细菌学培养及病原菌的菌群分布和耐药性。结果①740例糖尿病患者中合并尿路感染的81例,尿路感染发生率占10.95%,其中女性占82.7%,年龄60岁以上占65.4%;②细菌学检查率为77.8%,尿细菌培养阳性率为44.4%,尿细菌培养阴性率为33.4%;③尿细菌培养阳性36例,G-菌株占65.8%,大肠杆菌占52.6%,G 菌株占28.9%,粪肠球菌及葡萄球菌属各占10.5%,真菌2株占5.3%;④大肠杆菌对氨苄青霉素、头孢噻吩、培氟沙星、复方新诺明、阿莫西林/棒酸耐药率较高,粪肠球菌对喹诺酮类及四环素耐药率较高,葡萄球菌属对青霉素G、头孢唑啉、复方新诺明、红霉素、氨苄青霉素、阿莫西林/棒酸、左氧氟沙星、培氟沙星、庆大霉素耐药率较高。结论糖尿病患者由于免疫力低下,局部组织结构功能受损易于被病原菌侵袭和繁殖,故合并尿路感染应重视病原菌及其耐药性检测,对控制尿路感染、合理使用抗生素十分重要。     

Study of carrier frequency of Warsaw breakage syndrome in the Ashkenazi Jewish population and presentation of two cases

Warsaw breakage syndrome (WABS), caused by bi‐allelic variants in the DDX11 gene, is a rare cohesinopathy characterized by pre‐ and postnatal growth retardation, microcephaly, intellectual disability, facial dysmorphia, and sensorineural hearing loss due to cochlear hypoplasia. The DDX11 gene codes for an iron–sulfur DNA helicase in the Superfamily 2 helicases and plays an important role in genomic stability and maintenance. Fourteen individuals with WABS have been previously reported in the medical literature. Affected individuals have been of various ethnic backgrounds with different pathogenic variants. We report two unrelated individuals of Ashkenazi Jewish descent affected with WABS, who are homozygous for the c.1763‐1G>C variant in the DDX11 gene. Their phenotype is consistent with previously reported individuals. RNA studies showed that this variant causes an alternative splice acceptor site leading to a frameshift in the open reading frame. Carrier screening of the c.1763‐1G>C variant in the Jewish population revealed a high carrier frequency of 1 in 68 in the Ashkenazi Jewish population. Due to the high carrier frequency and the low number of affected individuals, we hypothesize a high rate of miscarriage of homozygous fetuses and/or subfertility for carrier couples. If the carrier frequency is reproducible in additional Ashkenazi Jewish populations, we suggest including DDX11 to Ashkenazi Jewish carrier screening panels.     

Chitosan hydrogel as a drug delivery carrier to control angiogenesis

An aqueous solution of photocrosslinkable chitosan containing azide groups and lactose moieties (Az-CH-LA) incorporating paclitaxel formed an insoluble hydrogel within 30 s of ultraviolet light (UV) irradiation. The chitosan hydrogel showed strong potential for use as a new tissue adhesive in surgical applications and wound dressing. The fibroblast growth factor (FGF)-2 molecules retained in the chitosan hydrogel and in an injectable chitosan/IO₄-heparin hydrogel remain biologically active, and were gradually released from the hydrogels as they biodegraded in vivo. The controlled release of biologically active FGF-2 molecules from the hydrogels caused induction of angiogenesis and collateral circulation occurred in healing-impaired diabetic (db/db) mice and in the ischemic limbs of rats. Paclitaxel, which is an antitumor reagent, was also retained in the chitosan hydrogel and remained biologically active as it was released on degradation of the hydrogel in vivo. The chitosan hydrogels incorporating paclitaxel effectively inhibited tumor growth and angiogenesis in mice. The purpose of this review is to describe the effectiveness of chitosan hydrogel as a local drug delivery carrier for agents (e.g., FGF-2 and paclitaxel) to control angiogenesis. It is thus proposed that chitosan hydrogel may be a promising new local carrier for drugs such as FGF-2 and paclitaxel to control vascularization.     

激光扫描共聚焦显微镜在肿瘤研究中的应用

激光扫描共聚焦显微镜是近年来出现的一种新的分子细胞生物学分析仪器,已经广泛应用于生物医学研究的许多领域.简介其基本功能和特点.并从肿瘤组织细胞蛋白的定位和定量、肿瘤细胞亚细胞结构观察、肿瘤受体研究、肿瘤药物分布和肿瘤多耐药机制等角度.综述了近年来激光扫描共聚焦显微镜在肿瘤研究中应用的进展.     

Perinatal hypophosphatasia: diagnosis and detection of heterozygote carriers within the family

We report on two families in which one or two children had a severe disorder of skeletal development detected by prenatal ultrasonography. The children died postnatally and showed typical radiological and biochemical findings of perinatal hypophosphatasia. Biochemical analysis revealed a low activity of alkaline phosphatase (AP) and a high value of pyridoxal-5-phosphate (PLP), one of its natural substrates. The screening for mutations of the tissue nonspecific alkaline phosphatase (TNSALP) gene showed homozygosity for a point mutation (G 317 --> D) in the two affected children of the first family. The affected child of the second family was homozygous for a nonsense mutation (R 411 --> X). Family screening revealed that the determination of AP and PLP is helpful for detection of heterozygotes. However, heterozygote children had values of AP in the lower normal range during phases of rapid growth. The determination of PLP proved to be more sensitive in these cases. It should be kept in mind that during the last trimester of gestation there is an increase in maternal AP activity and a normalization of PLP due to placental AP, which is not affected. Therefore, in the course of a prenatal diagnosis in an index case, paternal blood should be analyzed in parallel. For detailed genetic counseling and early prenatal diagnosis in following pregnancies, the possibility of mutation analysis should be used.     

Rapid molecular cytogenetic analysis of X-chromosomal microdeletions: Fluorescence in situ hybridization (FISH) for complex glycerol kinase deficiency

Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring timeconsuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita. We report an improved method for diagnosis of deletions in individuals with CGKD and for identification of female carriers within their families, using fluorescence in situ hybridization (FISH) with a cosmid marker (cosmid 35) within the glycerol kinase gene. When used in combination with an Xq control probe, affected males demonstrate a single signal from the control probe, while female carriers demonstrate a normal chromosome with two signals, as well as a deleted chromosome with a single signal from the control probe. FISH analysis for CGKD provides the advantages of speed and accuracy for evaluation of submicroscopic X-chromosomal deletions, particularly in identification of female carriers. In addition to improving carrier evaluation, FISH will make prenatal diagnosis of CGKD more readily available. © 1995 Wiley-Liss, Inc.     

Variable dystrophin expression in different muscles of a Duchenne muscular dystrophy carrier

The majority of Duchenne muscular dystrophy (DMD) female carriers show dystrophin immunostaining abnormalities, although a significant proportion of clinically non-manifesting carriers are normal following this analysis. We had the opportunity to study dystrophin immunostaining in two different muscles, the vastus lateralis and the rectus abdominis of a possible DMD carrier. While the vastus showed normal dystrophin immunostaining, pathological staining was detected in her rectus abdominis. These findings seem to indicate that dystrophin expression can vary in different muscle groups of a DMD carrier. The implications of these findings in DMD carrier detection and possible dystrophin function are discussed.     

神经管畸形患儿还原叶酸载体基因和叶酸之间交互作用

目的 探讨神经管畸形(neural tube defects,NTDs)患儿还原叶酸载体基因(reduced folate carrier gene,RFCI）A80G多态性与母亲孕早期未增补叶酸之间的关联性,为寻找NTDs危险因素的遗传易感标志物提供流行病学依据。方法采用限制性片段长度多态性-聚合酶链反应方法,对104个NTDs患儿及其母亲和100名正常儿童及其母亲的外周血DNA进行RFCI第80位单核苷酸多态性检测,通过病例对照研究,调查了后代RFCI A80G基因型与母亲孕期前后增补叶酸之间的基因环境交互作用。结果 RFCI GG基因型的子代发生NTDs危险高于AA基因型子代(OR=2．56,95％CI=1．04～6．36);母亲孕早期不增补叶酸,生育NTDs的危险高于增补叶酸的母亲(OR=7．69,95％CI=2．86～21．75);母亲孕期未增补叶酸,其子代GG基因型,发生NTDs的危险是AA基因型的3．30倍(95％CI=1．15～9．65);在叶酸和RFCI基因交互作用研究中,母亲未增补叶酸和子代GG基因型同时存在,发生NTDs的危险是8．80(95％CI=2．86～29．82),交互作用系数为1．45,,结论 在中国人群中,RFCI GG基因型可能是NTDs发生的遗传易感基因之一,子代RFCI GG基因型与母亲孕期叶酸缺乏之间存在交互作用,可能增加NTDs的发病危险。     

温敏型智能化靶向式药物载体研究（I）——具有温敏开关的多孔膜

研究了膜孔内接枝聚异丙基丙烯酰胺 (PNIPAM)“开关”的温敏型智能膜的制备 ,并对其进行了温度感应开关性能实验。实验中采用等离子体接枝填孔聚合法将 PNIPAM接枝在多孔平板膜的膜孔中 ,结果表明 ,这种接枝了 PNIPAM“开关”的多孔膜具有温度感应特性 ,其利用膜孔内 PNIPAM接枝链的膨胀 -收缩特性实现了感温性开关性能。当环境温度低于 PNIPAM的低临界溶解温度 (L CST)时 ,膜孔内 PNIPAM分子链膨胀而使膜孔呈“关闭”状态 ;而当环境温度高于 L CST时 ,PNIPAM分子链变为收缩状态而使膜孔“开启”。温敏开关的 L CST可通过添加丙烯酰胺 (AAM)与异丙基丙烯酰胺 (NIPAM)共聚来调节 ,AAM与 NIPAM共聚开关的 L CST随 AAM添加量的增加而单调上升。