Search PubMed⌕ Search

Biomedical subjects

C C Hsu

Publications and source records attributed to C C Hsu.

At least 109 records · Page 6Linked to original sources

Increased mortality from chronic liver disease and cirrhosis 13 years after the Taiwan "yucheng" ("oil disease") incident.

In 1979, a mass poisoning involving some 2,000 persons occurred in central Taiwan from cooking oil contaminated by polychlorinated biphenyls (PCBs) and their heat-degraded byproducts, including polychlorinated dibenzofurans (PCDFs). The responsible health department registered cases for clinical purposes between 1979 and 1983. The exposed persons are referred to as the "yucheng" (oil disease) cohort. PCBs and PCDFs are toxic chemicals widely dispersed in the environment and in human tissue, which persist long after exposure. The consequences of exposure to these agents are not well understood. We traced the cohort through December 31, 1991, and compared overall and cause-specific mortality of 1,837 "yucheng" subjects with age, gender, and calendar time-specific mortality rates for the Taiwan general population. Eighty-three deaths were identified from 23,404 observed person-years. Even though the overall standardized mortality ratio (SMR) was 0.8 (95% confidence interval (CI) 0.7-1.0), there was a substantial elevation in the mortality rate for chronic liver disease and cirrhosis (10 deaths, SMR = 2.7, 95% CI = 1.3-4.9). Mortality from malignant neoplasms and other causes was not significantly different from that of the Taiwan population. PCB/PCDF exposure appears to promote the development of severe liver disease, perhaps in combination with known risk factors such as infection with hepatitis B virus. Further follow-up of this young cohort is necessary to see if the consequences include hepatic cancer.

Adolescent↗

Epidemiologic study of occupational injuries among foreign and native workers in Taiwan.

This study was designed to compare the risk of occupational injuries in foreign workers compared to native workers in Taiwan. The cohort of foreign workers under study was constructed by records of legally registered workers migrated from foreign countries to Taiwan from July 1, 1991 to December 31, 1993. The native Taiwanese workers for comparison were labor-insured workers working in the same industries as foreign workers in 1992. The number of occupational injuries in the first year of employment were obtained by matching the cohort of foreign workers with the labor insurance payment records by name, birth date and passport number. The 1-year incidence rate of occupational injuries in the first year of employment was calculated and a standardized morbidity ratio (SMR) was used for comparison with adjustment for age distribution and to accommodate the small sample size of foreign workers. The risk to occupational injuries among total (SMR = 0.86) and male (SMR = 0.58) foreign workers was not higher; indeed, it was even lower, than that among native workers in Taiwan. However, the risk to female migrant workers, especially in the construction industry, was significantly higher than that of female Taiwanese workers (SMR = 1.60). Stratified by industry, the incidence was high in the fabricated metal products manufacturing industry and in machinery and equipment manufacturing industry for male foreign workers, while a high incidence for the female foreign workers occurred in construction industry and rubber products manufacturing industry. The risk of occupational injuries was greater for foreign workers who had been in Taiwan for only a short time. Most of the injuries occurred within the first 6 months of employment. Eighty-four out of the 394 occupational injuries among foreign workers resulted in disabilities. None of the accidents was fatal, but most of the disabilities were severe. The most common disabling injuries were cut or crushed fingers. The finding of a similar distribution of occupational injuries among foreign and native workers indicates that control measures are needed to reduce occupational injuries for all foreign and native workers in Taiwan.

Accidents, Occupational↗

Molecular cloning, structural analysis, and expression of carp ZP2 gene.

The cDNAs encoding carp ZP2 homologous to winter flounder and mammalian ZP2 were cloned. Carp ZP2 contains a tandemly repetitive domain and a nonrepetitive domain. A repeat is composed of 13 amino-acid residues whose consensus sequence is QQTSQQFQPQKPA/V. The length of the repetitive domain is highly variable, but that of the nonrepetitive domain is fairly constant among various cDNAs. The termination codons of various cDNAs appear at three different positions. Three groups of cDNAs were therefore categorized. Groups I-III encode a nonrepetitive domain of 356, 255, and 10 residues, respectively. A carp ZP2 gene corresponding to group II cDNA was cloned. It spans 2.4 kb and consists of eight exons and seven introns. Carp ZP2 mRNA was detected only in oocytes but not in other tissues. Carp ZP2 is heterogenous in size. The molecular weight ranges from 40-80 kDa. It is present in vitellogenic but not in previtellogenic oocytes, nor in other tissues. Carp ZP2 content in oocytes increases as vitellogenesis proceeds.

Amino Acid Sequence↗

Blood serum levels of PCBs and PCDFs in Yucheng women 14 years after exposure to a toxic rice oil.

In 1979, a mass poisoning of more than 2000 people occurred in central Taiwan due to consumption of rice-bran oil contaminated with PCBs and their heat-degraded byproducts. The incident was later referred to as Yucheng (oil disease). Serum samples from 56 women with the 1979 exposure were collected in February 1992 and analyzed for their contaminant content using sample enrichment and isotope dilution mass spectrometry. In most of the samples, levels of PCDFs and PCBs were detectable, and the median values of 2,3,4,7,8-PCDFs and 1,2,3,4,7,8-PCDFs were 1,030 and 2,220 ng/kg serum lipid, respectively. The median level of the total PCBs on a whole weight basis was 8,730 ng/kg. The PCB/PCDF concentrations in Yucheng women 14 years after the toxic exposure were still one to two orders of magnitude higher than controls. Concentrations of PCB levels in 1992 were positively correlated with the 1980-1981 measured PCB levels in these women and both PCBs and PCDFs were negatively correlated with the total duration when these women breast fed their children between 1979 and 1992. It is concluded that serum levels of congener-specific PCBs/PCDFs in exposed women are good indicators of previous exposure and may provide important information for more reliable estimation of dose-response relationship.

Benzofurans↗

The epidemiology and surveillance of blood lead in Taiwan (ROC): a report on the PRESS-BLL project.

To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July 1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 micrograms/dl in male workers and 11.6 micrograms/dl in female workers. The mean BLL of lead-exposed workers was significantly (P < 0.05, z-test) higher than that of the general Taiwanese population (8.6 micrograms/dl for males and 6.7 micrograms/dl for females). In addition, the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 micrograms/dl for males; 30 micrograms/dl for females). The workplaces and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination. These actions identified the causes of elevated BLLs and set up strategies to reduce workers' lead exposure. The establishment of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae.

Adolescent↗

Enhanced interleukin-4 expression in patients with endometriosis.

OBJECTIVE: To investigate the expression of cytokines by T-helper cells type 1 (interleukin [IL]-2 and interferon-gamma [IFN-gamma]) and type 2 (IL-4 and IL-10) in peripheral blood monocytes and peritoneal fluid (PF) cells from patients with endometriosis. DESIGN: Peripheral blood (PB) monocytes and PF cells from patients with endometriosis were isolated and the expression of cytokines investigated. SETTING: Institute for the treatment of endometriosis and research institute in university-based medical center. PATIENT(S): The study included 7 women with normal pelvic structure, 36 patients with endometriosis, and 7 women with pelvic adhesion but without apparent endometriotic lesion. The existence and severity of endometriosis was determined by laparoscopic examination. INTERVENTION(S): All patients received laparoscopic operation to identify the existence and stages of endometriosis. Danazol (200 mg, twice daily) was prescribed for those with endometriosis. MAIN OUTCOME MEASURE(S): Transcription of cytokines were directly analyzed using the reverse transcriptase-polymerase chain reaction method. The concentrations of cytokines in peritoneal fluids and sera were analyzed by the ELISA. RESULT(S): Levels of IL-4 messenger RNA (mRNA) and protein in the PB and peritoneal cells of patients with endometriosis were higher than those of normal patients, whereas levels of IFN-gamma mRNA and protein were suppressed. There were no significant changes in the mRNA or protein levels of IL-2 or IL-10 in both peritoneal fluids and sera. The level of IL-4 was reduced to normal after combined treatment with laparoscopic surgery and danazol. The secretion of IFN-gamma was elevated after treatment. CONCLUSION(S): Cytokine secretion by T-helper cells type 1 and type 2 is altered in women with endometriosis, suggesting that these T-helper subsets play a role in the immunologic responses to endometriosis.

Ascitic Fluid↗

Immunomodulation in women with endometriosis receiving GnRH agonist.

OBJECTIVE: To assess the changes in the subpopulations of lymphocytes and in lymphocyte mitogenic activity in women with endometriosis receiving GnRH-agonist treatment. METHODS: Twenty-six women with advanced endometriosis from the National Cheng Kung University Medical College were studied. Each received a total of six doses of GnRH agonist at 4-week intervals. Immunologic responses at various times after receiving GnRH-agonist treatment, including numbers of peripheral blood lymphocytes subsets and the lymphocyte proliferative activity, were analyzed using a repeated measures analysis of variance. Twenty-six healthy women who visited our gynecologic clinics for routine Papanicolaou smear examination at the time of the recruitment were enrolled as controls. The responses for each patient receiving GnRH agonist were normalized with respect to those of her matched control at each of the time points. The differences between post- and pretreatment data were estimated using generalized estimating equations. RESULTS: There was no significant difference in the sizes of lymphocyte subsets between patients and controls before treatment. After GnRH-agonist treatment, there was a trend in the rise of natural killer cell numbers early in the treatment period, with P values of .05 and .07 at 1-2 weeks and 2-3 weeks, respectively. This rise in natural killer cell numbers was not significant until 3-4 weeks and the second month after the treatment. There were no significant changes in the CD4+ and CD8+ T-cell subsets and B cells, although a slight increase in total T cells (ie, CD3+ T) was observed 1-2 weeks after receiving GnRH agonist. The T-cell mitogenic activities at the end of 2 and 4 months after GnRH-agonist treatment were 1.5 and 1.8 times, respectively, of those before treatment. CONCLUSION: The increase in natural killer cell numbers and the upregulation of T-lymphocyte mitogenic activity, which might be caused by a direct effect of GnRH agonist or a consequence resulting from the depression of estradiol by GnRH agonist, may have implications in the clinical treatment of endometriosis.

Adult↗

The use of an enteral expert system in the prescription of enteral formulas in a university hospital.

A personal computer-based expert system has been developed for the prescription of enteral formulas based on patient-need characteristics. Two hundred twelve inpatients in a university hospital setting were prospectively evaluated to compare the identity and cost of the enteral formula prescribed by the expert system with the identity and cost of the enteral formula prescribed by the ward team. Two hundred seven patients had complete data to allow analysis. There was a mean cost savings (+/-SD) of $1.18 +/- 7.69/d for each patient using the expert system compared with the MD-prescribed formula (P = 0.023). We project that the use of this program would save $27,564/y in our hospital (an average of 23,360 patient/days of enteral feeding per year). We conclude that the use of an expert system can be cost-effective in the prescription of enteral formulas for hospitalized patients.

Adult↗

Preparation of excipient-free recombinant human tissue-type plasminogen activator by lyophilization from ammonium bicarbonate solution: an investigation of the two-stage sublimation phenomenon.

Dry, excipient-free recombinant human tissue-type plasminogen activator (tPA) powder was prepared by lyophilization from ammonium bicarbonate solution. Ammonium bicarbonate sublimes into ammonia, water, and carbon dioxide upon lyophilization, without causing measurable harm to the protein. There were approximately 4 mol of residual ammonium ion per mole of lyophilized tPA. Under certain lyophilization conditions, a large pressure increase in the lyophilizer chamber occurred, presenting a pressure control problem. Microscopy and sublimation rate measurements on the frozen matrix revealed that ice sublimation occurred first, followed by the sublimation of ammonium bicarbonate. Analysis of the sectioned frozen matrix indicated that the bicarbonate salt was evenly distributed throughout the vial, suggesting that the delay of ammonium bicarbonate sublimation was not due to hindrance by ice. In the two-stage process, ice sublimation proceeded according to zero-order kinetics, whereas ammonium bicarbonate sublimation followed a grain-burning (2/ 3-order) model and was governed by a higher activation enthalpy. In most cases, the sublimation rate of ammonium bicarbonate in the presence of tPA was lower than that in the absence of the protein. Sublimation activation enthalpy for ammonium bicarbonate in the presence of tPA was 26.1 +/- 3.8 kcal/mol, which was approximately 10 kcal/mol greater than that for the tPA-free system. Consistent with a prediction from our kinetic modeling, a 6-h extension of primary drying enabled us to conduct lyophilization while maintaining pressure control.

Bicarbonates↗

Determining the water sorption monolayer of lyophilized pharmaceutical proteins.

The concept of monolayer water coverage is useful in the development of lyophilized protein formulations. Herein, we have explored three different methodologies to determine the water monolayer for pharmaceutical proteins: (1) theoretical prediction based on the amino acid composition and their relative propensities to sorb water; (2) a traditional adsorption isotherm measurement by Karl Fischer water titration of samples held at various relative humidities (created by saturated salt solutions); and (3) an adsorption isotherm measurement with a gravimetric sorption analyzer (GSA), which consists of a microbalance within a computer-controlled humidified environment. Data from the latter two methods were analyzed with the Brunauer-Emmett-Teller (BET) gas adsorption equation to yield experimental monolayers. In our study, we examined six different therapeutic proteins and found that for each case all three approaches yielded similar results for the water monolayer. We also attempted to use the BET equation to determine the water monolayer for a model sugar (trehalose) and polyol (mannitol), which are potential excipients in pharmaceutical protein formulations. We found that calculations from the data obtained by the traditional and GSA methods yielded consistent results for trehalose, which remained amorphous upon lyophilization. Mannitol tended to form anhydrous crystals upon freezedrying, and was thus not amenable to analysis. The utility of both traditional and GSA methods for determining the water monolayer was extended to colyophilized protein:sugar systems as well.

Adsorption↗

The effect of operating and formulation variables on the morphology of spray-dried protein particles.

The purpose of this research was to investigate the shape and morphology of various spray-dried protein powders as a function of spray-drying conditions and protein formulations. A benchtop spray dryer was used to spray dry three model proteins in formulation with a sugar or a surfactant. Physical characterizations of the powder included morphology (scanning electron microscopy), particle size, residual moisture, and X-ray powder diffraction analyses. A significant change in particle shape from irregular (e.g., "donut") to spherical was observed as the outlet temperature of the dryer was decreased. The drying air outlet temperature was shown to depend on various operating parameters and was found to correlate with the drying rate of atomized droplets in the drying chamber. The morphology of spray-dried protein particles was also affected by formulation. In protein:sugar formulations, spray-dried particles exhibited a smooth surface regardless of the protein-to-lactose ratio, whereas roughness was observed when mannitol was present at > 30% of total solids, due to recrystallization. Protein particles containing trehalose at concentrations > 50% were highly agglomerated. The presence of surfactant resulted in noticeably smoother, more spherical particles. The shape and the morphology of spray-dried powders are affected by spray drying conditions and protein formulation. This study provides information useful for development of dry proteins for fine powder (e.g., aerosol) applications.

Antibodies, Monoclonal↗

Aspirin improves uterine blood flow in the peri-implantation period.

A prospective clinical study at the Infertility Clinic of National Cheng Kung University Hospital investigated the effect of aspirin on infertile women with impaired uterine perfusion. A total of 127 women with unexplained infertility or repeated failure with various assisted-conception techniques were enrolled. Uterine perfusion was assessed by Doppler ultrasound and classified as normal or impaired (pulsatility index < 3.0 or > or = 3.0, respectively). One-third (43/127) of the women were found to have impaired uterine perfusion during their menstrual cycles. Those with impaired uterine blood flow were given aspirin (100 mg/day) starting on day 3 of the next ovulatory cycle. Only 36 women completed both the screening and the aspirin-treated cycles. The pulsatility index was measured in the natural and aspirin-treated cycles in the same group of women and compared using repeated measures analyses of variance. A significant improvement in the uterine blood perfusion (p < 0.05) was detected on the day leutinizing hormone peaked and in the midluteal phase (peri-implantation period) of aspirin-treated cycles. Thus, the use of low-dose aspirin may improve uterine perfusion in women with unexplained infertility and impaired uterine blood flow.

Adult↗

Diagnosis of left atrial thrombus with the aid of transesophageal echocardiography during aortic valve replacement: a case report.

Transthoracic echocardiography and cardiac angiography are the most common tools used in this hospital for evaluation of cardiac disease. Yet the specificity of either method in detection of left atrial pathologies is unsatisfactory. In a 76-year-old male, severe aortic regurgitation with congestive heart failure was impressed from preoperative studies including transthoracic echocardiography and cardiac angiography. However, left atrial thrombus was further detected during routine intraoperative transesophageal echocardiography. Surgical evacuation of a left atrial thrombus was done before undertaking aortic valve replacement. The timely finding was crucial for prevention of further complication and for expeditious use of definite therapy.

Aged↗

Bilateral laparoscopic gonadectomy for testicular feminization syndrome.

Defects of androgen receptor gene lead to testicular feminization syndrome, which is one of the most common etiology of male pseudohermaphroditism. A 22-year-old phenotypic female with primary amenorrhea and insomnia is presented. Gross appearance revealed sparse axillary and pubic hair, poor breast development, clitoromegaly and absence of vagina. Ultrasound demonstrated no evidence of the uterus or adnexal structures, but the prostate gland was found. The laboratory data showed elevated follicle-stimulating hormone and a male 46, XY karyotype. Computed tomography localized the position of bilateral undescending testes, which were removed by operative laparoscopy procedures later. The patient was discharged without complication postoperatively.

Adult↗

Contralateral temperature changes of the finger surface during video endoscopic sympathectomy for palmar hyperhidrosis.

One hundred and eight consecutive patients with primary palmar hyperhidrosis were surgically managed by coagulation of bilateral T2 sympathetic ganglia using video thoracoscopic techniques. Patients were divided into two groups. In the first group (N = 46), finger surface temperature of the ipsilateral index finger was recorded before and after T2 ganglionectomy. The average increase of post-operative temperature was 2.74 +/- 0.27 degrees C (mean +/- SE) on the right side and 2.67 +/- 0.33 degrees C on the left (P < 0.05). The significant rise of temperature resulting from sympatholytic vasodilatation was only noted in cases of exact ablation of the T2 ganglion. In the second group (N = 62), surface temperatures of both index fingers were monitored and recorded simultaneously. These patients were arbitrarily subdivided into Group 2-A (N = 29) when right side ganglionectomy was performed first and Group 2-B (N = 33) when left side ganglionectomy was done initially. After the first ganglionectomy was completed, an ipsilateral increase with a contralateral decrease of temperature was observed; the average increase of temperature was 1.92 +/- 0.35 degrees C and 2.19 +/- 0.30 degrees C, and the average decrease was 1.50 +/- 0.51 degrees C and 1.67 +/- 0.39 degrees C for Group 2-A and 2-B respectively (P < 0.05). The authors postulate that a cross-inhibitory effect by the post-ganglionic neurons innervating blood vessels of the upper extremities may exists in humans and this effect is released after ganglionectomy, resulting in contralateral vasoconstriction and decrease of finger surface temperature.

Adolescent↗

Advanced glycation endproducts-receptor interactions stimulate the growth of human pancreatic cancer cells through the induction of platelet-derived growth factor-B.

The molecular basis for the clinical association between diabetes mellitus and pancreatic cancer was investigated, using Mia PaCa-2 human pancreatic cancer cells in culture. Advanced glycation endproducts (AGE) prepared with bovine serum albumin and glucose were found to stimulate Mia PaCa-2 cell synthesis of DNA in a dose-dependent manner and also to significantly increase the number of viable cells. Evidence that platelet-derived growth factor-B (PDGF-B) mediates this growth promotion was obtained; AGE upregulated the level of PDGF-B mRNA, and antibodies against PDGF-BB completely neutralized the AGE-induced DNA synthesis. Antisense oligodeoxyribonucleotides complementary to mRNA encoding a receptor for AGE were found to reverse both the PDGF-B upregulation and the AGE-induced DNA synthesis. These results thus indicate that AGE ligand-receptor interactions could play an active part in the progression of pancreatic cancer through the induction of autocrine PDGF-B.

Base Sequence↗