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Y H Hsu

Publications and source records attributed to Y H Hsu.

At least 73 records · Page 4Linked to original sources
PubMed1995

Nucleotide sequence of a hop stunt viroid variant isolated from citrus growing in Taiwan.

The 303 nucleotide sequence of HSVd-citrus(T), a hop stunt viroid (HSVd) variant present in Etrog citron growing in Taiwan, was determined from cDNAs amplified by the polymerase chain reaction. HSVd-citrus(T) is very similar to several HSVd isolates previously recovered from citrus or cucumber, and exhibits microsequence heterogeneity at positions 154 and 181. Phylogenetic analysis using maximum parsimony grouped HSVd-citrus(T) with seven other isolates from citrus and cucumber in a large cluster of "citrus-type" isolates. A similar analysis revealed marked differences in both the extent and distribution of sequence variation among naturally occurring isolates of potato spindle tuber viroid.

Base Sequence↗
PubMed1995

Gonadoblastoma and chroiocarcinoma in dysgenic gonads: report of a case.

Dysgenetic gonads are well known to be associated with gonadoblastoma and various germ cell tumors, but very rarely with choriocarcinoma. We describe a 16-year-old, phenotypic female patient with a 46XY karyotype who developed gonadoblastoma on the right gonad and choriocarcinoma on the left. There was no co-existence of the two tumor cell types in the same gonad. This case emphasizes the importance of bilateral gonadectomy for "46XY female" patients, as soon as the cytogenetic evidence is known.

Adolescent↗
PubMed1994

A satellite RNA associated with bamboo mosaic potexvirus.

A small RNA molecule with properties of a satellite RNA was found in an isolate of bamboo mosaic potexvirus (BaMV-V) from Bambusa vulgaris McClure. This RNA (sBaMV RNA) and the genomic RNA of BaMV shared no significant sequence homology as assessed by hybridization with cDNA probes derived from the genomes of BaMV and sBaMV RNA. Replication of sBaMV RNA in barley protoplasts or Chenopodium quinoa was supported by BaMV, but not by potato virus X, the type member of the potexvirus group, or other unrelated viruses. The complete nucleotide sequence of sBaMV RNA is 836 nucleotides (excluding the poly(A) tail) and contains an open reading frame which starts after a 159-nucleotide 5'-untranslated region and encodes a 20,154-mol wt protein. In an in vitro rabbit reticulocyte lysate system, sBaMV RNA directed the synthesis of a protein estimated to be 25 kDa by SDS-polyacrylamide gel electrophoresis. The sBaMV RNA-encoded protein was not immunoprecipitated with antiserum against BaMV capsid protein. However, the sBaMV RNA was encapsidated with BaMV capsid protein to form rod-shaped particles with an average length of 60 nm as shown by immunoelectron microscopy. This is the first satellite RNA found in the potexvirus group.

Amino Acid Sequence↗
PubMed1994

Second-site mutations in the brome mosaic virus RNA3 intercistronic region partially suppress a defect in coat protein mRNA transcription.

An intercistronic oligo(A) tract is present in the genomic RNA3 of all bromoviruses sequenced to date and, for brome mosaic virus (BMV), is known to function as an activating sequence in transcription of the subgenomic coat protein mRNA, RNA4. Mutations able to partially compensate for removal of the oligo(A) from BMV RNA3 were identified by obtaining spontaneous second-site revertants. The starting BMV RNA3 mutant carried a deletion of 17 of 18 residues of the intercistronic oligo(A), resulting in a nearly complete loss of subgenomic coat protein mRNA synthesis and reduced RNA3 accumulation. The responsible suppressor mutations acted in cis and were located in the 244-base RNA3 intercistronic region containing the original deletion. Three mutations associated with the revertant phenotype were characterized: (i) A single U-->A substitution in the core subgenomic mRNA promoter restored 35% of wild-type promoter activity. (ii) A duplication of 8 bases (UAUUAUUA) immediately 5' to the oligo(A) deletion site resulted in higher levels of both RNA3 and RNA4 accumulation. (iii) A point substitution in a conserved cellular motif corresponding to box B of RNA polymerase III promoters reduced RNA3 accumulation. Together with certain intervirally conserved promoter sequences, the spontaneous adaptation of a bromovirus subgenomic promoter to function without its unusual oligo(A) activator suggests that bromovirus subgenomic mRNA transcription may share underlying mechanistic similarities with the many other members of the alphavirus-like superfamily, whose subgenomic promoters all lack an oligo(A) tract.

Base Sequence↗
PubMed1994

Nucleotide sequence of the genomic RNA of bamboo mosaic potexvirus.

The complete nucleotide sequence of the genomic RNA of bamboo mosaic virus (BaMV) was determined by sequencing a set of overlapping cDNA clones and by direct sequencing of the viral RNA. The RNA genome of BaMV is 6366 nucleotides long [excluding 3'poly(A) tail] and contains six open reading frames (ORFs 1 to 6) coding for polypeptides with M(r) values of 155K, 28K, 13K, 6K, 25K and 14K, respectively. The genome organization and sizes of the encoded proteins are very similar to those of other potexviruses which have been sequenced except that ORF 6 lies completely within ORF 1. The first five putative proteins of the BaMV genome show identities ranging between 44 to 59%, 26 to 49%, 30 to 53%, 15 to 35% and 20 to 30%, respectively, to the corresponding ORFs of other members of the potexvirus group. However the putative product ORF 6 shows no significant similarity to those of other potexvirus ORF products.

Amino Acid Sequence↗
PubMed1994

Could the cytokeratin molecule be modulated during tumor transformation in hepatocellular carcinoma?

The stability of cytokeratin during tumor transformation in hepatocellular carcinoma was studied. We applied biochemical methodology to look into the switching of cytokeratin molecules in tumor transformation. First, by centrifugation the cytokeratin molecules were extracted from both liver and hepatoma tissues. The extracts were then soaked with cyanogen bromide-activated Sepharose 4B beads previously coated by monoclonal anti-cytokeratin antibody. The bound molecules were then released from the resin with salt. Second, the isolated molecules of both were treated with lysosomal enzyme and analyzed on two-dimensional gels. The results demonstrated that there was a modulation in cytokeratin molecules, and the hepatoma cytokeratin was generated from the hepatocyte cytokeratin.

Blotting, Western↗
PubMed1993

Epstein-Barr virus-containing T-cell lymphoma presents with hemophagocytic syndrome mimicking malignant histiocytosis.

BACKGROUND: The previously designated malignant histiocytosis (MH) may include lymphoid neoplasms of T-cell lineage as well as patients with benign virus-associated hemophagocytic syndrome (VAHS). In this study, the association of Epstein-Barr virus (EBV) with T cell lymphomas which present with clinicopathologic features indistinguishable from malignant histiocytosis (MH) was investigated further. METHODS: Four adult patients, three women and one man, were admitted because of fever, cutaneous lesions, hepatosplenomegaly, and jaundice. Laboratory examinations revealed pancytopenia, abnormal liver functions and coagulopathy. All patients ran a fulminant course terminating in a hemophagocytic syndrome within 1 month. Immunophenotypic study, Southern blot analysis, and in situ hybridization were performed on the specimens obtained from the four patients. RESULTS: The biopsy-necropsy specimens from skin, liver, spleen, and bone marrow showed infiltration of atypical large cells with reactive histiocytosis and florid hemophagocytosis activity. Based on the clinical and histologic findings, these cases would have been designated as MH by previous criteria. Immunophenotypic, Southern blot, and in situ hybridization studies, however, showed clonotypic proliferation of EBV genomes in the nuclei of the large atypical cells that expressed T-cell antigens. Therefore, these patients should be diagnosed as a recently described EBV-associated peripheral T-cell lymphoma (EBV-PTCL). CONCLUSIONS: EBV-PTCL may present with a fulminant hemophagocytic syndrome indistinguishable from the previously designated MH. This finding represents a step forward in our changing concept regarding MH, some of which only recently has been suggested to be of T-cell lymphoma origin. Differentiation from benign VAHS is clinically important. Features useful in this distinction are tabulated and discussed.

Adult↗
PubMed1993

Left ventricular pseudoaneurysm diagnosed by magnetic resonance imaging in a nine-year-old boy.

An asymptomatic 9-year-old boy was found to have a cardiac murmur in a heart disease survey. Two-dimensional echocardiogram identified a large left ventricular pseudoaneurysm. Color flow imaging showed a transtunnel "to-and-fro" mosaic pattern between the pseudoaneurysm and left ventricle. ECG-gated magnetic resonance imaging demonstrated the exact size and related location of the left ventricular pseudoaneurysm and its ostium. Without cardiac catheterization or angiography, he was successfully operated on by closure of the communicating tunnel.

Child↗
PubMed1993

Post-embedding in situ hybridization for localization of viral nucleic acid in ultra-thin sections.

We developed an in situ hybridization technique for localization of plant virus RNA in ultra-thin sections of virus-infected, Lowicryl HM20- or osmium-fixed, Araldite-embedded plant leaf tissues. A digoxigenin-labeled in vitro transcript corresponding to 173 nucleotides at the 3' end of bamboo mosaic virus (BaMV) RNA was used as a riboprobe and the hybrids were detected by incubation with sheep antidigoxigenin antibody followed by gold-labeled rabbit anti-sheep IgG. Pre-treatment of ultra-thin sections with an etching agent was the critical step in enhancing hybridization signals on Lowicryl-embedded thin sections. Etching combined with K-metaperiodate treatment increased the accessibility of nucleic acids to riboprobes in osmicated Araldite-embedded sections. BaMV RNA was specifically detected within chloroplasts, mitochondria, and nuclei of infected cells. BaMV virions and BaMV-specific electron-dense crystalline bodies were also labeled. The labeling intensity on Lowicryl-embedded samples, in general, was much higher than that on osmicated Araldite-embedded samples. However, our procedure offers the advantage that it permits labeling of viral nucleic acids in tissues already processed for routine EM and should be applicable for in situ labeling of any cellular nucleic acids.

Blotting, Northern↗
PubMed1993

Subcapsular hemorrhage of the liver in a neonate with extremely low birthweight.

Subcapsular hemorrhage of the liver (SHL) is usually an autopsy finding rather than a clinical diagnosis. Recent literature has noted an increased incidence of SHL in premature infants. A 26-week, 899 g female was born via emergency cesarean section due to excessive vaginal bleeding. At birth and during the first few days of life, the infant presented with anemia which was masked by concomitant maternal antepartum hemorrhage and neonatal intraventricular hemorrhage. SHL was suspected when the infant developed marked anemia, abdominal distension and hemoperitoneum on day 11 of life. Despite supportive transfusions, the infant's condition deteriorated and she died at 15 days of age. A large subcapsular hematoma of the liver was found at autopsy. We thus conclude that SHL should be considered in the normal course of differential diagnosis of acute blood loss in premature neonates.

Anemia↗
PubMed1993

Familial medullary thyroid carcinoma: report of three cases in a family.

Familial medullary thyroid carcinoma is a distinct clinical entity in which early diagnosis by screening of family members for elevated calcitonin levels can be useful. A 33-year-old female was hospitalized because of an enlarging left thyroid mass. Resected thyroid showed medullary thyroid carcinoma. Her mother had received a total thyroidectomy due to the same disease 10 years previously, and her younger brother had an elevated basal calcitonin level of 468 pg/mL when the index case was diagnosed. The younger brother was advised to undergo surgery; a total thyroidectomy also revealed medullary thyroid carcinoma. There was no evidence of multiple endocrine neoplasia in the family. Recognition of new cases by screening with a basal or provocative test in families of patients with medullary thyroid carcinoma should be mandatory.

Adult↗
PubMed1992

Neonatal lupus erythematosus: a case report.

Neonatal lupus erythematosus is a syndrome characterized by congenital heart block and/or cutaneous lupus erythematosus in the presence of maternal autoantibodies. We report a female newborn with cutaneous lesions of the neonatal lupus erythematosus born to a clinically asymptomatic mother. She presented with erythematous maculopapules on the face, neck and upper trunk at birth. Complete blood cell count showed leukopenia and thrombocytopenia. Antinuclear antibodies, anti-Ro/SSA and anti-La/SSB antibodies were positive in the mother and infant. The skin lesions became annular, erythematous and slightly scaling three weeks later. A skin biopsy performed at seven weeks of age showed edema of the dermis and perivascular mononuclear cell infiltration. Immunofluorescent studies showed immune complex deposition of IgG an IgM in the basal zone of epidermis. She received supportive treatment and sun avoidance. Hematologic abnormalities recovered by nine weeks of age. Skin lesions faded gradually during the following four months, leaving residual hypopigmentation and telangiectasia.

Female↗
PubMed1991

Impact of intraoperative echocardiography on surgical management of congenital heart disease.

Intraoperative echocardiography was performed by epicardial, 2-dimensional, low- and high-pulsed repetition frequency, continuous-wave Doppler and color flow mapping in 50 patients. Forty studies were performed before and 44 studies after cardiopulmonary bypass. Studies before cardiopulmonary bypass agreed with preoperative evaluation. After cardiopulmonary bypass, studies revealed that 11 of 25 patients who underwent repair of ventricular septal defects had residual ventricular septal defects, and 1 of 25 patients who underwent atrial septal repair had 1 residual atrial communication. One patient with a "Swiss cheese" ventricular septum underwent repeat cardiopulmonary bypass to close residual ventricular septal defects. The patient with a residual atrial communication required immediate reoperation because of a right to left shunt after a modified Fontan procedure. Eight of 10 remaining residual ventricular septal defects spontaneously closed 1 to 41 days after operation. Assessment of postcardiopulmonary bypass and postoperative valvular regurgitation in 21 valves revealed good correlation (p less than 0.01). However, 1 patient required reoperation for mitral valve replacement on the sixth postoperative day. The correlation was fair between postcardiopulmonary bypass and postoperative residual stenotic pressure gradients in 12 surgically repaired stenotic lesions. This study shows that little additional information is added to a comprehensive preoperative evaluation by precardiopulmonary bypass intraoperative echocardiography. Postcardiopulmonary bypass intraoperative echocardiography is useful in identifying residual shunts. Assessment of stenotic gradients and valvular regurgitation must be interpreted in light of a changing hemodynamic state.

Cardiopulmonary Bypass↗
PubMed1991

Potential diagnosis of hemodynamic abnormalities in patent ductus arteriosus by cine magnetic resonance imaging.

Cine magnetic resonance imaging was performed in 11 patients with communication between systemic and pulmonary circulation. In five patients with uncomplicated patent ductus arteriosus (PDA), ductus arteriosus was delineated by a persistent band of low signal intensity, whereas in two patients who also had severe pulmonary hypertension the signal intensity was varied. Two separate low signal intensities in the main pulmonary artery and the descending aorta were each uniformly recorded in the five patients with uncomplicated PDA, consistent with continuous left-to-right shunt and turbulent flow acceleration, respectively. In one of the patients with severe pulmonary hypertension but not Eisenmenger's syndrome, the areas of low signal intensity from left-to-right shunt and turbulent flow acceleration diminished. In the patient with Eisenmenger's PDA the right-to-left shunt was also characterized by an area of low signal intensity but with a reversal in direction. Cine MR imaging has the potential to be a noninvasive and supplemental method for evaluating PDA.

Adolescent↗
PubMed1989

Comparison of proteins and nucleic acids of Echinochloa ragged stunt and rice ragged stunt viruses.

Echinochloa ragged stunt virus (ERSV) and rice ragged stunt virus (RRSV; Reoviridae) were purified from their respective host plants and disrupted in SDS. Evidence for the double-strandedness of ERSV RNA was obtained. Electrophoresis in 10% polyacrylamide gels resolved the RNAs of each virus into 10 segments, ranging for ERSV from 0.61 x 10(6) to 2.8 x 10(6) daltons, with a sum representing the total genome of 17.89 x 10(6) daltons, and for RRSV from 0.6 x 10(6) to 2.98 x 10(6) daltons, with a sum of 18.15 x 10(6) daltons. Although the overall RNA pattern of the two viruses was similar, there were distinctive features. Using 7.5-15% polyacrylamide gels, electrophoresis of SDS-dissociated RRSV particles yielded five major proteins of 129 x 10(3), 123 x 10(3), 63 x 10(3) and 35 x 10(3) daltons, and two minor proteins of 113 x 10(3) and 88 x 10(3) daltons, respectively, while comparable samples of ERSV yielded four major proteins of 127 x 10(3), 123 x 10(3), 63 x 10(3) and 34 x 10(3) daltons, and three minor proteins of 103 x 10(3), 50 x 10(3) and 49 x 10(3) daltons, respectively. We conclude from this and other evidence that ERSV and RRSV are closely related viruses and should be classified in the same subgroup, despite reported differences in the morphology of their outer capsids.

Acridine Orange↗