BACKGROUNDCongenital cataract is a highly heterogeneous disorder at both the genetic and phenotypic levels. This study was conducted to identify disease locus for autosomal dominant congenital cataracts in a four generation Chinese family.

METHODSFamily history and clinical data were recorded. All the members were genotyped with microsatellite markers which are close to the known genetic loci for autosomal congenital cataracts. Two-point Lod scores were obtained using the MLINK of the LINKAGE program package (ver 5.1). Candidate genes were amplified by polymerase chain reaction (PCR) and direct cycle sequencing.

RESULTSThe maximum Lod score of Zmax-2.11 was obtained with three microsatellite markers D22S258, D22S315, and D22S1163 at recombination fraction theta=0. Haplotype analysis showed that the disease gene was localized to a 18.5 Mbp region on chromosome 22 flanked by markers D22S1174 and D22S270, spanning the beta-crystallin gene cluster. A c.752T-->C mutation in exon 6 of CRYBB1 gene, which resulted in a heterozygous S228P mutation in predicted protein, was found to cosegregate with cataract in the family.

CONCLUSIONSThis study identified a novel mutation in CRYBB1 gene in a Chinese family with autosomal dominant congenital cataract. These results provide strong evidence that CRYBB1 is a pathogenic gene for congenital cataract.

Amino Acid Sequence ; Cataract ; congenital ; genetics ; Female ; Genes, Dominant ; Genetic Linkage ; Humans ; Male ; Molecular Sequence Data ; Mutation, Missense ; beta-Crystallin B Chain ; genetics

OBJECTIVETo observe the oral acute toxicity of of (+)-usnic acid in mice and assess its cytotoxicity in rat cardiac fibroblasts.

METHODSThe mice with acute poisoning of (+)-usnic acid at different doses by oral administration were observed for toxic manifestations, and the LD(50) was determined. The survival time and survival rate of the mice receiving different doses of (+)-usnic acid were observed. Cultured rat cardiac fibroblasts were inoculated with different concentrations of (+)-usnic acid, and the cell growth inhibition rate was estimated and the IC(50) determined using MTT assay.

RESULTSHigher dose of (+)-usnic acid resulted in more obvious symptoms of poisoning and shorter survival time of the mice. The LD(50) of (+)-usnic acid in mice by oral administration was 388 mg/kg. The manifestations of poisoning such as apathism, pilomotor, chill, dyspnea, torpidity and anorexia was observed. Rat cardiac fibroblasts incubated with (+)-usnic acid showed obvious growth inhibition, which was positively correlated to the dose of (+)-usnic acid, and high dose of (+)-usnic acid caused severe cell injuries. The IC(50) of (+)-usnic acid in rat cardiac fibroblasts was 322 microg/ml.

CONCLUSION(+)-usnic acid is a natural compound of low toxicity in mice, and low to medium dose of (+)-usnic acid dose not produce obvious cytotoxicity.

Administration, Oral ; Animals ; Benzofurans ; administration & dosage ; chemistry ; toxicity ; Fibroblasts ; drug effects ; Lethal Dose 50 ; Mice ; Myocardium ; cytology ; Rats ; Stereoisomerism

BACKGROUNDAtrial fibrillation is a common arrhythmia with multi-factorial pathogenesis. Recently, a single nucleotide polymorphism (G/T) at position 1057 in the KCNE4 gene, resulting in a glutamic acid (Glu, E)/aspartic acid (Asp, D) substitution at position 145 of the KCNE4 peptide, was found in our laboratory to be associated with idiopathic atrial fibrillation (atrial fibrillation more frequent with KCNE4 145D). However, the functional effect of the KCNE4 145E/D polymorphism is still unknown.

METHODSWe constructed KCNE4 (145E/D) expression plasmids and transiently co-transfected them with the KCNQ1 gene into Chinese hamster ovary-K1 cells and performed whole-cell patch-clamping recording to identify the possible functional consequences of the single nucleotide polymorphism. Quantitative data were analyzed by Student;s t test. Probability values less than 0.05 were considered statistically significant.

RESULTSA slowly activating, non-inactivating voltage-dependent current ((24.0 +/- 2.9) pA/pF, at +60 mV)) could be recorded in the cells transfected with KCNQ1 alone. Co-expression of wild type KCNE4 inhibited the KCNQ1 current ((7.3 +/- 1.1) pA/pF)). By contrast, co-expression of KCNE4 (145D) augment the KCNQ1 current ((42.9 +/- 7) pA/pF)). The V(1/2) of activation for the KCNQ1/KCNE4 (145D) current was shifted significantly towards the depolarizing potential compared to that for the KCNQ1 current ((-2.3 +/- 0.2) mv vs (-13.0 +/- 1.5) mv, P < 0.01)) without changing the slope factorkappa. Furthermore, KCNE4 (145D) also affected the activation and deactivation kinetics of KCNQ1 channels.

CONCLUSIONWe provide experimental evidence that the KCNE4 (145E/D) polymorphism exerts the effect of "gain of function" on the KCNQ1 channel. It may underlie the genetic mechanism of atrial fibrillation. Further studies on the functional association between I(Ks) and KCNE4 (145D) polymorphism in cardiac myocytes are suggested.

Animals ; CHO Cells ; Cricetinae ; Cricetulus ; Humans ; KCNQ1 Potassium Channel ; physiology ; Polymorphism, Single Nucleotide ; Potassium Channels, Voltage-Gated ; analysis ; genetics ; physiology

OBJECTIVETo assess the feasibility of the 10 microg recombination yeast hepatitis B vaccine in the expanded applicable population group aged 5 - 18.

METHODSPeople with both HBsAg and anti-HBs negative were selected to take two-stage clinical experiment and the safety and immunogenicity were observed. Safety observation was conducted in 925 subjects, while 568 for immunogenicity. The observation group (aged 5 - 18) included 493 subjects, and (age > 18) 75 enrolled in control group. For the observation group, there were three sub-groups including a child group (141, aged 5 - 6), early youth group (177, aged 12 - 13), and youth group (175, aged 16 - 18). Both groups were administered with 10 microg recombination yeast hepatitis B vaccines with 3 doses at 0 month, 1st month, 6th month. To assess the immunogenicity, the vaccination reactions were observed during the following 4 weeks in order to assess the vaccine safety. The blood samples were taken during 4 - 6 weeks after fully vaccinated, and then anti-HBs were tested with RIA and analyzed by comparing the positive rate of anti-HBs, the geometric mean titer (GMT) and the protective rate between the two groups.

RESULTSBoth observation and control group didn't show any general reactions, adverse events following immunization (AEFI) or coincidental cases when observed at 0.5 h, 6 h, 24 h, 48 h, 72 h, 1 week, 2 weeks, 3 weeks, 4 weeks after being vaccinated. The result of serum test showed, the positive rates of child group, early youth group, youth group and control group were respectively 100.00% (141/141), 97.18% (172/177), 98.29% (172/175) and 89.33% (67/75); the GMTs of anti-HBs were respectively 440.28, 875.38, 467.80, 131.06 U/L; the protective rates were respectively 100.00% (141/141), 97.18% (172/177), 97.14% (170/175) and 86.67% (65/75). The positive rate, GMT and protective rate of the experimental group were all higher than that of control group (chi(2)(positive rate) = 12.77, 5.12, 7.99; t(GMT) = 3.89, 4.13, 5.91; chi(2)(protective rate) = 16.81, 8.60, 8.44; P < 0.05).

CONCLUSIONThis vaccine could be expanded to 5 - 18 year-old population with safety and effectiveness, the positive rate and protective rate of anti-HBs were both higher than that of control group.

Adolescent ; Child ; Child, Preschool ; Female ; Hepatitis B Antibodies ; blood ; immunology ; Hepatitis B Surface Antigens ; blood ; immunology ; Hepatitis B Vaccines ; administration & dosage ; adverse effects ; immunology ; Humans ; Male ; Vaccines, Synthetic ; administration & dosage ; adverse effects ; immunology