Biomedical subjects

K H Hsu

Publications and source records attributed to K H Hsu.

At least 37 records · Page 2Linked to original sources

PubMed1999

Correlation of clinical and ultrasonographic features in congenital muscular torticollis.

OBJECTIVE: To find the relationship between the ultrasonographic pictures and the clinical features of patients with congenital muscular torticollis (CMT). DESIGN: Prospective survey of patients with clinically suspected CMT by high-resolution ultrasonography. SETTING: Rehabilitation department of a tertiary care center. PARTICIPANTS: Two hundred fifty-six CMT patients, from the ages of 9 days to 16yrs, with a mean follow-up period of 6.7 months. MAIN OUTCOME MEASURES: Correlation of the ultrasound appearance of the involved sternocleidomastoid (SCM) muscles with clinical features. The pathologic findings in diseased muscles from patients who underwent surgical intervention were also evaluated. RESULTS: Muscle abnormalities were identified ultrasonographically in 218 CMT patients (85%) and were classified into four types: a fibrotic mass in the involved muscle (type I, 15%); diffuse fibrosis mixing with normal muscle (type II, 77%) and without normal muscle in the involved muscle (type III, 5%); and a fibrotic cord in the involved muscle (type IV, 3%). Compared with type I patients, type IV patients were more likely to undergo surgical treatment (odds ratio = 31.54, p = .0196). Type III patients were more likely to undergo surgical treatment, although this tendency was not statistically significant. CONCLUSION: Ultrasonography can precisely identify pathologic changes in the involved SCM muscle of CMT patients. Type III and IV patients are more likely to require surgical intervention.

Adolescent↗

PubMed1998

Use of the antral follicle count to predict the outcome of assisted reproductive technologies.

OBJECTIVE: To evaluate the predictive value of the antral follicle count in patients undergoing assisted reproductive technologies (ARTs). DESIGN: Prospective study. SETTING: Tertiary care institutional hospital. PATIENT(S): Consecutively seen patients undergoing ARTs such as IVF-ET, gamete intrafallopian transfer, and tubal embryo transfer (TET). INTERVENTION(S): The ovarian antral follicle number was determined by transvaginal ultrasonography on the first or second menstrual day, before the administration of gonadotropins, in patients undergoing ARTs. MAIN OUTCOME MEASURE(S): Ovulation induction was accomplished with the use of GnRH agonist down-regulation combined with FSH and menotropin stimulation. Gamete intrafallopian transfer or TET was performed in patients with patent fallopian tubes, and IVF-ET was undertaken in the remaining patients. Analysis of variance and Mantel-Haenszel monotonic test for trends were used for data analysis. RESULT(S): A total of 149 treatment cycles for 130 couples were performed during the study period. The procedures performed included 89 ETs, 26 gamete intrafallopian transfers, 13 TET cycles, and 21 incomplete cycles (9 poor responders, 6 failed retrievals, and 6 nonfertilization cycles). All treatment cycles were divided into three groups according to the number of antral follicles (i.e., < or = 3, 4-10, and > or = 11) to evaluate the influence of various factors. The antral follicle count correlated significantly with patient age, day 3 serum FSH level, use of gonadotropins, serum estradiol concentration, number of oocytes retrieved, and, later, number of oocytes or embryos transferred. The group of patients who had a lower antral follicle count also had a significantly higher rate of cycle cancellation compared with the other two groups (68.8% vs. 5.3% and 0, respectively). No pregnancies occurred in the low antral follicle count group, whereas there was a trend toward an increasing number of pregnancies per attempt as the number of antral follicles increased (0, 23.7%, and 36.8%, respectively). CONCLUSION(S): It is easy to determine the number of antral follicles with a diameter of 2-5 mm on the first or second day of menstruation, or just before the administration of exogenous gonadotropins. We were able to predict the ovarian response and pregnancy results of patients undergoing ARTs with the use of this simple procedure.

Embryo Transfer↗

PubMed1998

Lung function and general illness symptoms in a semiconductor manufacturing facility.

Large quantities of potent gases, dopants, photoactive chemicals (photoresists, photoinitiators), solvents, and ionizing radiation are used in the semiconductor manufacturing process, but little is known about the occurrence of respiratory disease from exposures in this industry. The purpose of this study was to assess the pulmonary risk by conducting pulmonary function tests and symptoms survey in a semiconductor plant in Taiwan. This study is part of a clinical survey conducted on 926 workers in a semiconductor plant in Taiwan in July 1995. The study items included a standard self-administered questionnaire, chest x-rays, pulmonary function tests, and physical examinations in 249 workers. There was a borderline significance of higher prevalence (P = 0.06) of restrictive lung abnormality in male photolithographic workers (4 of 21; 19.1%) than in male control workers (0 of 17; 0%), and the smoking- and age-adjusted odds ratio was 4.1 (95% confidence interval [CI], 0.41-41.6). There was a significantly higher prevalence (P = 0.02) of restrictive lung abnormality in male ion-implantation workers (5 of 19; 26.3%) than in male control workers (0 of 17; 0%), and the smoking- and age-adjusted odds ratio was 3.7 (95% CI, 0.52-26.7). There were significantly higher prevalences of airway irritation, eye irritation, headache, stress, tiredness, and poor memory in female photolithographic or etch/diffusion workers than in control workers. This study suggests that restrictive lung abnormality is a potential health effect in male silicon-wafer fabrication workers in the semiconductor industry. The tasks of male process, maintenance, and equipment engineers put them at risk for intermittent short-term peak exposure. This may account for a higher prevalence of mild restrictive lung abnormality among male engineers of photolithographic and ionimplantation sections. The findings of this medical surveillance are tentative, but they suggest that further investigation of the etiologic factors and the subsequent health effects is necessary.

Adult↗

PubMed1997

The influence of endometriosis on the success of gamete intrafallopian transfer (GIFT).

PURPOSE: Our purpose was to evaluate the outcomes of gamete intrafallopian transfer (GIFT) therapy in patients with endometriosis. METHODS: One hundred eight GIFT cycles performed under the indication of endometriosis were compared to 156 GIFT cycles with indications of other disease entities. A maximum of seven oocytes was transferred into one or both fimbriate ends with prepared spermatozoa. Clinical pregnancy rates and outcomes were evaluated according to Mantel-Haenszel's chi-square test. Multiple logistic regression analysis was performed to determine factors influencing the success on pregnancy in the total treatment cycles. RESULTS: The anthropological variables, such as age of patients, duration of infertility, and semen grading, were comparable in both groups. The responses to controlled ovarian hyperstimulation (COH) were progressively decreased while increasing the severity of endometriosis conditions such as nonendometriosis, mild-form endometriosis, and advanced-form endometriosis patients. However, there were no significant differences in the clinical pregnancy rates (40.4, 36.7, and 41.7%, respectively), multiple pregnancy rates (34.9, 27.3, and 45.0%, respectively), and early pregnancy loss rates (27.0, 18.2, and 30.0%, respectively). Multivariate statistics of pregnancy rates that adjusted the effects of patients' age, tubal health, presence of active endometriosis and/or endometriomas, number of oocytes transferred, and quality of sperm exhibited no statistical significance between endometriosis and nonendometriosis groups. CONCLUSIONS: Our data show that patients with records of endometriosis have both a decreased ovarian response to gonadotropin stimulation and a decreased number of retrieved oocytes. Since the number of oocytes needed for the GIFT procedure is limited, pregnancy results for patients in the study group were comparable with those for patients in the control group.

Analysis of Variance↗

PubMed1995

Isolation and characterization of a highly attenuated respiratory syncytial virus (RSV) vaccine candidate by mutagenesis of the incompletely attenuated RSV A2 ts-1 NG-1 mutant virus.

Ts-1, a temperature sensitive (ts) mutant of RSV, was previously derived from RSV A2 virus by mutagenesis with 5-fluorouracil (5-FU). Ts-1 was attenuated for adult volunteers and seropositive children but retained a low level of virulence in seronegative infant vaccinees as indicated by the occurrence of upper respiratory tract disease. Ts-1 NG-1, a more defective derivative of ts-1, was produced by mutagenesis of ts-1 with nitrosoguanidine. However, ts-1 NG-1 still retained a low level of virulence for the upper respiratory tract and showed some genetic instability in chimpanzees. With renewed interest in the goal of developing a live, attenuated RSV vaccine, we have now attempted to further attenuate ts-1 NG-1 by mutagenesis with 5-FU and 5-azacytidine. Four mutants that are phenotypically different from the ts-1 NG-1 parental virus were identified. Each of the four mutants was more restricted in replication in BALB/c mice compared with the ts-1 NG-1 parental virus. One of the ts-1 NG-1 derivatives, termed A-20-4, which showed the lowest (35 degrees C) in vitro shutoff temperature and which was also completely restricted in replication in BALB/c mice, was selected for further evaluation in seronegative chimpanzees. A-20-4 did not cause rhinorrhea in chimpanzees but induced detectable titers of serum RSV neutralizing antibodies in 2 of 4 chimpanzees. Apparent complete protection to subsequent challenge with wild-type RSV was observed in each of the four chimpanzees previously immunized with A-20-4.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Efficacy of adenovirus-vectored respiratory syncytial virus vaccines in a new ferret model.

In the absence of an adequate small animal model for testing the efficacy of adenovirus-vectored respiratory syncytial virus (RSV) vaccines, a ferret model was established for this purpose. Recombinant adenovirus types 4, 5 and 7 expressing the RSV fusion glycoprotein (F), the attachment glycoprotein (G) or both F and G were constructed previously. These recombinants contain a deletion of a large portion of the E3 region of the respective adenovirus vector. In addition, an Ad7(E3+)F recombinant virus which contains an intact E3 region was constructed to assess whether E3 region functions might enhance vaccine immunogenicity. Evaluation of these viruses in the ferret model demonstrated that Ad4 and Ad5 recombinants, administered intranasally to ferrets, induce stronger seroresponses to RSV than do Ad7 recombinant viruses. Ad7(E3+)F did not show enhanced immunogenicity relative to E3-deleted recombinant viruses. However, measurement of RSV infectivity in nasal washes, following intranasal RSV challenge, showed that five different vaccination regimens, Ad7F/Ad4F, Ad7G/Ad4G, Ad7FG/Ad4FG, Ad4F/Ad7(E3+)F and Ad5F/Ad4F, protected ferrets from RSV infection in a dose-dependent manner.

Animals↗

PubMed1993

Serial deletion constructs of human cardiac myosin heavy chain genes generated by PCR amplification.

Serial deletion constructs derived from the 5'-flanking regions of the human cardiac alpha- and beta-myosin heavy chain genes were generated by polymerase chain reaction (PCR) amplifications. Generation of different length chimeric constructs were based on the complete sequence of the human cardiac myosin heavy chain genes. The primers were synthesized with HindIII and BamH1 sites and were linked to any designed nucleotide of the 5' flanking sequence of the myosin heavy chain gene(s). Following the PCR amplification and the site-directed mutagenesis, the PCR products were verified by DNA sequencing and subsequently ligated to the chloramphenicol acetyltransferase (pBLCAT3) reporter gene which was restricted with Hind III and BamH1. Neonatal rat cardiocytes were used to assay the promotor activity (i.e. CAT activity) of different lengths of the chimeric constructs of the gene.

Animals↗

PubMed1992

Regulation of human cardiac myosin heavy chain genes: the effect of catecholamine.

The 5'-flanking regions of the alpha- and beta-cardiac myosin heavy chain (MyHC) genes were excised from the cosmid human genomic clones using Hind III and Xbal for the alpha-MyHC gene, and the Hind III and Hind III sites for the beta-MyHC gene. These fragments were linked to chloramphenicol acetyl transferase (CAT) vector to generate a chimeric fusion gene. These fusion genes were subsequently transfected to neonatal rat cardiac cultured cells to analyze the CAT activity. The alpha-MyHC gene is preferentially expressed as compared to the beta-MyHC. In the presence of norepinephrine (NE) the beta-MyHC gene is remarkably induced (within 24 hours following the addition of norepinephrine to the cardiocyte culture). However, the alpha-MyHC is also induced. Specific alpha andrenergic antagonists such as terazosin (Tz) partially suppressed both the alpha- and beta-MyHC genes as revealed by the CAT activity. These findings suggest that catecholamine does activate the human cardiac MyHC genes but does not differentiate the specific expression of either the alpha- or beta-MyHC genes.

Animals↗

PubMed1992

Endothelin stimulates cardiac alpha- and beta- myosin heavy chain gene expression.

The effect of endothelin-1 on cardiac myosin heavy chain gene expression was examined using an isolated neonatal rat myocardial cell culture system. The effects of endothelin-1 on the expression of alpha- and beta- myosin heavy chain genes in the primary rat myocardial cell culture system were examined by S1 nuclease protection analysis. Endothelin-1 was found to stimulate both alpha- and beta- myosin heavy chain gene expression. The 5' flanking regions of both the alpha- and beta- myosin heavy chain gene promoters ligated to a reporter gene, chloramphenicol acetyltransferase, were used to study the effect of endothelin-1 on transcription. Myocardial cells treated with endothelin-1 increased the transcription rate of alpha- and beta- myosin heavy chain genes in a dose-dependent manner. Thus, the hypertrophic effect of endothelin-1 on cardiac myocytes involves augmentation of alpha- and beta- myosin heavy chain gene expression by increasing gene transcription.

Animals↗

PubMed1992

Immunogenicity of recombinant adenovirus-respiratory syncytial virus vaccines with adenovirus types 4, 5, and 7 vectors in dogs and a chimpanzee.

Recombinant adenovirus type 4, 5, and 7 expressing the fusion glycoprotein (F) gene, the attachment glycoprotein (G) gene, or both F and G genes of respiratory syncytial virus (RSV) was constructed. Intratracheal immunization of dogs with Ad7F induced moderate titers of RSV-neutralizing antibodies. After booster immunization with Ad4F, the dogs developed high titers of RSV-specific antibody. Subsequently, three two-dose vaccination regimens, Ad4F/Ad5F, Ad7G/Ad4G, and Ad7FG/Ad4FG, were compared with Ad7F/Ad4F for immunogenicity and protective efficacy. The results indicated that Ad4F/Ad5F was equal or greater in immunogenicity to Ad7F/Ad4F, but Ad7G/Ad4G and Ad7FG/Ad4FG were less effective than Ad7F/Ad4F in inducing RSV-neutralizing antibody. All vaccination regimens completely protected the lungs of dogs from RSV infection. A chimpanzee was sequentially immunized orally with Ad7F, Ad4F, and Ad5F. A low-level antibody response to RSV was induced after the primary immunization, but no significant increases were observed after booster immunizations.

Adenoviruses, Human↗

PubMed1991

Adenovirus vectors for gene expression.

Adenoviruses possess a combination of features that make them highly suitable as vectors for expression of heterologous genes. Non-conditional and non-defective adeno-vectors have been constructed to obtain high level expression of a number of foreign genes and some of them have been shown in animal models to exhibit excellent promise as vaccine candidates.

Adenoviridae↗

PubMed1989

Characterization of a YAC-1 mouse cell receptor for group B coxsackieviruses.

A receptor on YAC-1 cells, a mouse T-lymphoma cell line, bound all six serotypes of the group B coxsackieviruses (CVB). In addition, the cells produced infectious virus. Each of the CVB competed for the same receptor on YAC-1 cells. CVB3 bound relatively slowly to YAC-1 cells (k = 4 x 10(-11) min-1 cell-1), and there were only 500 attachment sites per cell. A rabbit antiserum prepared against the HeLa cell receptor protein Rp-a specifically inhibited the binding of CVB1 and CVB3. A virus-receptor complex with CVB3 could be isolated from detergent (0.5% sodium deoxycholate, 1% Triton X-100)-solubilized YAC-1 plasma membranes. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the iodinated virus-receptor complex revealed a band with the same mobility as Rp-a. The results suggested that the YAC-1 receptor for CVB resembles that of the HeLa cell receptor.

Animals↗

PubMed1988

A monoclonal antibody specific for the cellular receptor for the group B coxsackieviruses.

A 50-kilodalton receptor protein (Rp-a) for the group B coxsackieviruses (CB) was isolated in a virus-receptor complex from detergent-solubilized HeLa cells (J. E. Mapoles, D. L. Krah, and R. L. Crowell, J. Virol. 55:560-566, 1985). It was used as an immunogen for preparation of a mouse monoclonal antibody (RmcB) which protected HeLa cells and Buffalo green monkey kidney cells from infection by all six serotypes of CB. RmcB did not protect HeLa cells from infection by poliovirus, echovirus 6, or coxsackievirus A18. This monoclonal antibody differed in receptor epitope specificity from a previously isolated antibody (RmcA) (R. L. Crowell, A. K. Field, W. A. Schleif, W. L. Long, R. J. Colonno, J. E. Mapoles, and E. A. Emini, J. Virol. 57:438-445, 1986) which blocked receptors only for type 1 CB (CB1), CB3, CB5, and echovirus 6. RmcA and RmcB recognized two distinct saturable receptors on HeLa cells, designated HR2 and HR1, respectively. Human rhabdomyosarcoma (RD) cells have the HR2 receptor for CB3-RD (a variant of CB3), but lack the HR1 receptor for CB3. Therefore, RD cells were resistant to infection by CB3. Although binding of CB3-RD to the HR2 receptor on RD cells can lead to infection, binding of CB3-RD to the HR2 receptor on HeLa cells did not lead to infection. Apparently, both CB3 and CB3-RD use only the HR1 receptor for infection of HeLa cells. Thus, a given virus may use two distinct receptors to bind to cells when only one virus-receptor interaction leads to infection.

Animals↗

PubMed1985

Macrophage-mediated natural cytotoxicity of dimethyl sulfoxide-treated Friend erythroleukemia cells.

Dimethyl sulfoxide (DMSO) treatment of the Friend erythroleukemia cell line GM 979 markedly increased its susceptibility to natural cytotoxicity by splenocytes from normal inbred DBA/2 mice. Cytotoxicity occurred with normal adherent spleen cells as well as dextran-elicited peritoneal exudate (PE) cells but not with resident PE cells. Susceptibility of the leukemia cells to natural cytotoxicity increased to maximum levels upon treatment with 210 mM DMSO for 2-3 days. The natural cytotoxicity assayed by the 51Cr release procedure was first detectable after 9 hours of incubation and reached maximum levels by 24-30 hours. Although both DMSO and n-butyric acid induced rapid erythroid cell differentiation of the GM 979 cells, and both resulted in increased hemoglobin synthesis, only DMSO treatment enhanced the susceptibility of the cells to natural cytotoxicity by normal splenocytes. Cell-free supernatants from adherent spleen cells cocultured with DMSO-treated GM 979 cells for 6-15 hours were markedly cytotoxic for cultures of other chromium-labeled DMSO-treated leukemia cells. Supernatants from cultured adherent spleen cells alone, or lysates of DMSO-treated leukemia cells, did not possess cytotoxic activity. Resident peritoneal macrophages also had no cytotoxic activity against DMSO-treated cells, and culture supernatants from resident PE cells, even after incubation with DMSO-treated target cells, failed to show significant levels of cytotoxicity. These results indicate that normal splenic adherent cells as well as elicited PE cells have the ability to lyse DMSO-treated leukemia cells.

Animals↗

PubMed1984

Thirty years after isoniazid. Its impact on tuberculosis in children and adolescents.

This is the final report of 30 years of observation of isoniazid prophylaxis and chemotherapy of tuberculosis in children. It includes 2,494 patients who completed a course of prescribed therapy in Houston and who had been under observation for a total of 15,943 person-years. The effectiveness of isoniazid prophylaxis was best demonstrated in those children infected before 4 years of age, because none of them have experienced overt disease. Chemotherapy of pulmonary tuberculosis was effective for existing disease in all ages and prevented dissemination. Of those treated for pulmonary tuberculosis during childhood, the striking absence of adolescent reactivation points to the likelihood of a permanent cure. Adequate drug therapy is the key to successful treatment.

Adolescent↗

PubMed1984

Dexamethasone inhibition of DMSO-induced transglutaminase activity and differentiation of leukemic cells.

Treatment of the Friend erythroleukemic (FL) cell line GM979 with dimethyl sulfoxide (DMSO) or n-butyric acid induced erythroid differentiation. Transglutaminase (TGase) activity also increased in these treated cells. Glucocortical steroids, i.e., dexamethasone (DEX) and triamcinolone acetonide, when added to the cultured medium, inhibited the DMSO-induced hemoglobin synthesis but not n-butyric acid-induced hemoglobin synthesis. Similarly, these steroids inhibited DMSO-increased TGase activity but not n-butyric acid-increased TGase activity in intact FL cells. Neither the differentiation-inducing agents nor the steroids had any effect on TGase activity when they were directly added to cell lysates. These results support the view that the increase of TGase activity may be related to erythroid differentiation of FL cells and of its possible role of this enzyme in FL cell-induced differentiation.

Animals↗

PubMed1984

Lymphoblastoid cell-induced suppression of human peripheral blood leukocyte mitogenic responses.

Two lymphoblastoid tumor cell lines, the Burkitt lymphoma derived BJAB cell line which is free of Epstein-Barr virus (EBV) and B95-8 cells, which are marmoset lymphocytes transformed by EBV isolated from an infectious mononucleosis patient, were studied in regards to their effects on the blastogenic responsiveness of normal human peripheral blood leukocytes stimulated in vitro with mitogens. Mitomycin C treated tumor cell suspensions, when cocultured with normal human blood leukocytes, markedly depressed the expected blastogenic responses in vitro to concanavalin A, pokeweed mitogen, and phytohemagglutin. In addition, cell-free sonicates from the cell lines also depressed blastogenic responsiveness of the leukocytes in vitro. Heating the sonicates for 10 min at 100 degrees C markedly diminished the suppressive properties of the sonicates, as did ultraviolet light irradiation. The suppressive activity of the B95-8 sonicates was pelleted by high speed centrifugation as compared to the activity of sonicates derived from the BJAB cells. Further studies are warranted to determine the nature and mechanism of suppression of blastogenic responsiveness of normal human leukocytes by soluble components derived from such lymphoblastoid cell lines.

Animals↗

PubMed1983

Tuberculin reaction in children treated with isoniazid.

This study involved 370 children infected by Mycobacterium tuberculosis. Follow-up tests, three to nine years after a course of isoniazid treatment, showed that the tuberculin reactions remained strongly positive, although some fluctuation in size was observed. The persistence of tuberculin hypersensitivity in these patients was considered an asset, as delayed-type hypersensitivity and cell-mediated immunity are related closely, according to recent studies on antituberculosis immunology. With the risk of endogenous disease removed by isoniazid treatment, the patients gained a bonus of cell-mediated immunity to protect them from future exogenous reinfection.

Child↗