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Y S Shin

Publications and source records attributed to Y S Shin.

At least 73 records · Page 4Linked to original sources

Molecular characterization of Duarte-1 and Duarte-2 variants of galactose-1-phosphate uridyltransferase.

The N314D polymorphism was found in two different alleles of the galactose-1-phosphate uridyltransferase (GALT) gene, Duarte-1 (D1) and Duarte-2 (D2). Although both variants have identical electrophoretic mobility and isoelectro-focusing points, the galactose-1-phosphate uridyltransferase (GALT) activity varies: D1 alleles showed 110-130% of the normal RBC activity, but D2 alleles only 40-50%. We found that D1 alleles also carried a silent mutation in exon 7 (L218L) in addition to N314D. In contrast, besides N314D, D2 alleles carried two regulatory mutations, G1105C and G1391A, in introns D and E, respectively. In normal and Q188R alleles none of the above four mutations coexisted. However, some galactosaemia alleles with mutations other than Q188R, such as W316X and E340X of exon 10, also carried the N314D mutation. The W316X alleles existed in cis with the intron mutations (G1105C and G1391A), whereas those with E340X are in cis with L218L. In all cases examined, the intron mutations were not found in D1 alleles and no D2 alleles had the silent mutation of L218L. These results suggest that the decrease in the GALT activity in D2 may be due to regulation of the GALT gene expression. The G1105C site may be critical to the function of erythroid transcription factor NF-E1, since it flanks the core consensus sequence for one of its binding sites. The G1391A mutation may affect another cis-acting regulatory sequence. Alternatively, both mutations may be involved in an aberrant splice processing, which possibly results in a low level of correctly spliced mRNA.

Alleles↗

Three missense mutations in the galactose-1-phosphate uridyltransferase gene of three families with mild galactosaemia.

UNLABELLED: Classical galactosaemia caused by deficiency of galactose-1-phosphate uridyltransferase (GALT) is characterized by acute symptoms of hepatocellular dysfunction, sepsis, cataracts and failure to thrive. Galactose limitation reverses these complications immediately, however, most of these children have a long-term complication of verbal dyspraxia mental retardation and ovarian failure. The GALT gene was cloned and several mutations including the common Q188R have been reported. In this study the coding region of GALT was amplified by polymerase chain reaction from genomic DNA of classical galactosaemic individuals and characterized by direct sequencing of the products. Three missense mutations were identified in three patients with a mild galactosaemic variant: (1) replacement of threonine-138 by methionine (T138M); (2) replacement of arginine by tryptophan (R259W); and (3) replacement of threonine by alanine (T350A). All three galactosaemic individuals, one girl and two boys, have varying degrees of residual GALT activity in RBC and their galactose-1-phosphate levels decreased much faster than in other galactosaemic patients. These missense mutations occur in regions that are not highly conserved domains. CONCLUSION: The study of the molecular basis related to the phenotype variation may indeed help to prognosticate the outcome of patients with classical galactosaemia.

Amino Acid Sequence↗

A mild adult myopathic variant of type IV glycogenosis.

Type IV glycogenosis is usually a rapidly progressive disease of early childhood, causing death before 4 years of age. It is characterized by hepatosplenomegaly, cirrhosis, and chronic hepatic failure. Muscle involvement is generally overshadowed by liver disease. A mild non-infantile variant of type IV glycogenosis has been described in a few patients. In some of them, the patients suffered foremost from chronic progressive myopathy. We here report on a female patient aged 51 years who had experienced difficulties in climbing stairs for 2 years due to leg weakness. EMG revealed a myopathic pattern. The muscle biopsy findings revealed polyglycosan bodies. Biochemical investigation showed absence of branching enzyme in muscle but not in leukocytes and fibroblasts.

Adult↗

Mutation hotspots in the PHKA2 gene in X-linked liver glycogenosis due to phosphorylase kinase deficiency with atypical activity in blood cells (XLG2).

In five cases of X-linked liver glycogenosis subtype 2 (XLG2), we have identified mutations in the gene encoding the liver isoform of the phosphorylase kinase alpha subunit (PHKA2). XLG2 is a rare variant of X-linked phosphorylase kinase (Phk) deficiency of the liver. Whereas in the more common form of X-linked hepatic Phk deficiency, XLG1, the enzyme's activity is decreased both in liver and in blood cells, Phk activity in XLG2 is low in liver but normal or even enhanced in blood cells. Although missense, nonsense and splicesite mutations in the PHKA2 gene were recently identified in several cases of XLG1, no mutations have yet been described for XLG2 and a molecular explanation for the peculiar biochemical phenotype of XLG2 has been lacking. All mutations found in the present study result in non-conservative amino acid replacements of residues that are absolutely conserved between the alpha L, alpha M and beta subunits of Phk [H132P, H132Y, R186H (twice) and D299G]. Strikingly, in two pairs of cases the mutations affect the same codon. These results demonstrate that: (i) XLG2 is caused by mutations in PHKA2 and is therefore allelic with XLG1; and (ii) XLG2 mutations appear to cluster in limited sequence regions or even individual codons.

Amino Acid Sequence↗

Acute effect of qigong training on stress hormonal levels in man.

We observed the acute effects of Qigong training on the levels of human endogenous opioid peptides, such as beta-endorphin, and other stress hormones [adrenocorticotrophic hormone (ACTH), cortisol, and dehydroepiandrosterone-sulfate (DHEA-S)] in a group of ChunDoSunBup Qigong trainees. At pre (-10 min), mid (40 min) and post (70 min) time of training, blood was taken for the determination of plasma level of hormones. The level of beta-endorphin was significantly increased during the mid-time of training while the level of ACTH declined at the mid- and post-time of training. Cortisol and DHEA-S were not significantly changed during training. This result suggests that Qigong training, as a stress coping method, affects and plays a role in hormonal regulation related to the maintenance of homeostasis in man.

Adrenocorticotropic Hormone↗

Epidemiological observations on recent outbreaks of canine distemper in Tokyo area.

Recent outbreaks of canine distemper virus (CDV) infection in Tokyo area were investigated on the basis of clinical features and serological test. The affected dogs were clinically classified into two groups; dog with respiratory and gastrointestinal signs associated with central nervous system (CNS) signs, and those with CNS signs alone. Of 62 dogs examined, 34 belonged to the former and 28 to the latter. In immunoperoxidase assay, anti-Onderstepoort strain of CDV serum reacted at a low level against 2 field isolates of CDV. These results suggested the presence of different types of CDV population in the field.

Animals↗

Serological analysis of canine distemper virus using an immunocapture ELISA.

As a rapid and sensitive method to detect canine distemper virus (CDV), an immunocapture enzyme-linked immunosorbent assay (ELISA) was performed. The sensitivity and specificity of the immunocapture ELISA were considered to be high enough. Virus neutralizing (VN) test was also established using the immunocapture ELISA. By using this test, the different cross VN titers between sera of dogs experimentally infected with the Onderstepoort strain and those with a field isolate of CDV were observed.

Animals↗

Prenatal diagnosis of the urea cycle diseases: a survey of the European cases.

A European survey of prenatal diagnosis cases involving urea cycle diseases was performed. Citrullinemia was the most frequently investigated disease (108 cases). Other diseases are, in order of frequency, argininosuccinic aciduria (75 cases), ornithine transcarbamylase defect (52 cases), carbamoylphosphate synthetase defect (8 cases), triple H (3 cases), and arginase deficiency (1 case). Only one disease (ornithine transcarbamylase defect) is presently diagnosed using molecular biology methods.

Argininosuccinic Acid↗

Characterization of two stop codon mutations in the galactose-1-phosphate uridyltransferase gene of three male galactosemic patients with severe clinical manifestation.

Classical galactosemia, which is caused by deficiency of galactose-1-phosphate uridyltransferase, is characterized by acute problems of hepatocellular dysfunction, sepsis, cataracts and failure to thrive. Galactose limitation reverses these symptoms immediately; however, the long-term complications, such as mental retardation and ovarian failures are major problems in most of these patients. In order to investigate the molecular basis for phenotype variation in galactosemia, we have screened the most common mutation in the GALT gene, Q188R. We have further examined those patients who are heterozygous for Q188R or negative for this mutation by SSCP analysis and direct sequencing. In three male patients, we have identified, for the first time, two stop-codon mutations in the GALT gene, G212X (exon 7) and E340X (exon 10). Two patients of 8 and 28 years of age, respectively, who are compound heterozygotes for Q188R and G212X, have severe mental retardation and their general clinical condition is more severe than that of patients with missense mutations. The third patient, who is 8 years of age and who is homozygous for E340X, the N314D polymorphism and a silent substitution L218L, presents with a relatively normal physical and mental condition to date.

Adult↗

Lens sorbitol dehydrogenase deficiency in a patient with congenital cataract.

UNLABELLED: Lens sorbitol dehydrogenase activity was assayed in patients with congenital cataracts, senile cataracts, without cataracts and in one fetal lens. In patients with congenital cataracts we did not observe any abnormality of galactose and sorbitol metabolising enzymes in erythrocytes. In one of these patients with inexplicable congenital cataracts lens sorbitol dehydrogenase deficiency was found. CONCLUSION: Determination of galactose metabolising enzymes, sorbitol dehydrogenase and polyols in lenses may help in understanding the mechanism of formation of inexplicable congenital cataracts.

Cataract↗

Mutations in the galactose-1-phosphate uridyltransferase gene of two families with mild galactosaemia variants.

Classical galactosaemia, deficiency of galactose-1-phosphate uridyltransferase (GALT), is characterized by acute symptoms of hepatomegaly, jaundice, sepsis, cataracts and growth retardation. Treatment with dietary galactose restriction corrects these complications immediately; however, most of these children develop long-term complications of verbal dyspraxia, mental retardation and ovarian failure. Our previous molecular study showed that the most common mutation of the GALT gene is a missense mutation of Q188R (replacement of glutamine-188 by arginine) in approximately 60-65% of the German galactosaemic population. The coding region of GALT was amplified by the polymerase chain reaction from genomic DNA of classical galactosaemic individuals, who are negative or heterozygous for Q188R, and was further characterized by direct sequencing. Three new disease-causing mutations, two missense and a stop codon mutation, were identified in three patients from two families with mild galactosaemic variants: firstly R67C, replacement of arginine-67 by cysteine and W316X, the stop codon at tryptophan-316 in one male; secondly A330V, replacement of alanine-330 by valine in two female siblings. In the first family the patient was also heterozygous for the polymorphism N314D and in the second family both girls were compound heterozygotes for Q188R and A330V. All three galactosaemic individuals have a considerable amount of the residual GALT activity in RBC and the galactose-1-phosphate (GALP) level decreased much faster on treatment than that of other galactosaemic patients with missense mutations such as Q188R. The clinical and biochemical data of these patients were much more favourable in comparison with those of two female galactosaemic individuals, one homozygous for L195P and the other compound heterozygous for Q188R and L195P. These three missense mutations (R67C, L195P and A330V) also occur in highly conserved regions. These observations suggest that the phenotypic variation in galactosaemic individuals may be due to different molecular aetiologies.

Adolescent↗

Immunohistochemical analysis of the lymphoid organs of dogs naturally infected with canine distemper virus.

The pathogenesis of acute canine distemper in three naturally infected dogs was investigated. The lymphoid organs showed atrophy without secondary follicles. The distribution of canine distemper virus (CDV) antigens was examined immunohistochemically with monoclonal antibodies specific for canine Thy-1, immunoglobulin (Ig) M, CD4, CD8, CD21 and CD45RB, and anti-measles virus nucleocapsid protein serum. The viral antigens were located in the T-cell-dependent areas and in the follicles of lymphoid organs; they were observed mainly in the Thy-1, or CD4-positive cells, but also in the CD8-, CD21-, or IgM-positive cells. The results indicated that Thy-1-positive and CD4-positive T cells serve as major target cells for CDV during the acute stage of infection.

Animals↗

Immunohistochemical studies of lymphoid tissues of rabbits infected with rinderpest virus.

The pathogenesis of infection with the L-strain of rinderpest virus (RPV) in rabbits was investigated. Of several lymphoid tissues examined, those associated with the gut showed the most marked virus growth. The virus titres were maximal 4 days after inoculation but had declined at day 6. The distribution of viral antigen was examined immunohistochemically with the recently established anti-rabbit CD5 monoclonal antibody (MoAb), which is a pan-T-cell marker, and the anti-RPV-nucleoprotein MoAb. The virus antigen was localized in the CD5+ area at the initial stage of infection but spread to all areas of the lymphoid tissues at the later stages. By flow cytometric analysis with both rabbit CD5 and CD4 MoAbs, a decrease of the CD4+ and CD5+ subpopulations was observed in the spleen and mesenteric lymph nodes.

Animals↗

Serological survey of canine distemper virus infection using enzyme-linked immunosorbent assay.

For detection of antibodies against canine distemper virus (CDV), an enzyme-linked immunosorbent assay (ELISA) was developed using a crude extract from cells infected with the Onderstepoort strain of CDV as antigen. Twenty-six sera from dogs experimentally vaccinated with the Snyder-Hill strain of CDV were compared by ELISA and a standard virus neutralization (NV) test. Since a good correlation between the titers obtained by both tests was observed, ELISA was considered to be a rapid and reliable method for a serological survey of CDV infection. When a total of 167 sera from dogs suspected of canine distemper under natural conditions were examined by the ELISA, 29 of the sera (17%) were found to have low VN antibody titers and high ELISA titers. The reason for the discrepancy in the titers was discussed.

Animals↗

Hospital accreditation--a universal perspective.

Hospital accreditation is professional and national recognition reserved for hospitals that provide high-quality health care. From the United States to the United Kingdom, many countries have introduced a hospital accreditation programme for the purpose of assuring high-quality health services. The standards used in accreditation programmes previously focused on structural evaluation, but recently attention is being turned to outcome evaluation. Initially discussing the international experiences of accreditation programmes, the author goes on to examine Korea and its Government's plans to implement a new accreditation programme in the near future, which will constitute an important part of the governmental healthcare reform plan.

Accreditation↗

Localization of a new type of X-linked liver glycogenosis to the chromosomal region Xp22 containing the liver alpha-subunit of phosphorylase kinase (PHKA2).

We describe here a new type of X-linked liver glycogen storage disease. The main symptoms include liver enlargement and growth retardation. The clinical and biochemical abnormalities of this glycogenosis are similar to those of classical X-linked liver glycogenosis due to phosphorylase kinase deficiency (XLG). However, in contrast to patients with XLG, the patients described here have no reduced phosphorylase kinase activity in erythrocytes and leukocytes, and no enzyme deficiency could be found. Linkage analysis of four families with this X-linked type of liver glycogenosis assigned the disease gene to Xp22. Lod scores obtained with the markers DXS987, DXS207, and DXS999 were 3.97, 2.71, and 2.40, respectively, all at 0% recombination. Multipoint linkage analysis localized the disease gene between DXS143 and DXS989 with a maximum lod score of 4.70 at theta = 0, relative to DXS987. As both the classical XLG gene and the liver alpha-subunit of PHK (PHKA2) are also located in Xp22, this variant type of XLG may be allelic to classical XLG, and both diseases may be caused by mutations in PHKA2. Therefore, we propose to classify XLG as XLG type I (the classical type of XLG) and XLG type II (the variant type of XLG).

Adolescent↗