Search PubMed⌕ Search

Biomedical subjects

S Y Chen

Publications and source records attributed to S Y Chen.

At least 55 records · Page 3Linked to original sources

Clinical features of familial gout and effects of probable genetic association between gout and its related disorders.

We examined whether the age at onset, gender, arthritic manifestations, and tophus formation in familial gout are different from those in nonfamilial gout, and we also examined the contributory effect of genetic association to the concurrence of hypertriglyceridemia, hypercholesterolemia, type 2 diabetes mellitus (DM), hypertension, obesity, and renal insufficiency with gout in Taiwan. A total of 21,373 gout patients' data from Ho-Ping Gout database were analyzed in this study retrospectively. The clinical and laboratory data were compared between familial and nonfamilial gout. Mean age at onset of gout in familial subjects was significantly 7.5 years lower than that of nonfamilial subjects (40.9 +/- 13.4 v 48.4 +/- 14.2 years, P =.0001), while gender, arthritic severity, and tophus formation were not significantly different between these 2 groups. Familial gout had lower serum triglyceride (TG), total cholesterol (TC), and percentage of hypertension than nonfamilial gout (182.4 +/- 125.3 v 195.9 +/- 135.8 mg/dL, P =.0001; 207.5 +/- 42.5 v 210.4 +/- 48.8 mg/dL, P =.0003; and 19.57% v 22.56%, P <.0001, respectively). Their serum creatinine, body mass index (BMI), and percentage of type 2 DM were not significantly different. Our results demonstrate that familial gout is associated with precocious onset. Furthermore, the contributory effect of genetic association to the concurrence of hyperlipidemia and hypertension with gout is less than that of environmental factors, while the effect of genetic association to the concurrence of obesity, type 2 DM, and renal insufficiency with gout is equivalent to that of environmental factors.

Age of Onset↗

MILDOS uranium milling dose assessment code update.

The MILDOS-AREA code was developed to estimate radiological doses and risks from uranium milling activities. The code has been used for demonstrating radiological compliance regarding the U.S. Nuclear Regulatory Commission's licensing requirements for uranium milling activities. The code was recently updated with an enhanced software package to address the following four areas: regulatory changes, in-situ leaching extraction technologies, software user interfaces, and software distribution technologies via the internet. Users can now specify in-situ leaching processes through a Windows object-based Geographic information System interface with incorporated updated regulation methodologies. The code and documentation are freely distributed through the Internet.

Humans↗

Heart rate responses and oxygen consumption during Tai Chi Chuan practice.

Tai Chi Chuan (TCC) is a popular Chinese conditioning exercise, however, its exercise intensity remains controversial. The objective of this study was to determine the exercise intensity of Yang TCC by measuring heart rate (HR) responses and oxygen consumption (VO2) during practice. Fifteen men aged 39.9 +/- 9.5 yrs (range 26-56 yrs) participated in this study. Subjects had practiced classical Yang TCC for 5.8 +/- 2.4 years. HR responses and VO2 were measured during practice of TCC by using a K4 telemetry system. Blood lactate was measured before and immediately after TCC practice. Additionally, breath-by-breath measurement of cardiorespiratory function and sequential determination of blood lactate were performed during the incremental exercise of leg cycling. Measurements obtained during the TCC practice and exercise testing were compared to determine the exercise intensity of TCC. While performing TCC, the mean HR of subjects was 140 +/- 10 bpm, and the mean VO2 was 21.4 +/- 1.5 mL x kg(-1) min(-1). Compared with the data of the exercise test, the HR during practice was 58% of the heart rate range. Meanwhile, the VO2 during TCC practice was 55% of the VO2peak. Additionally, the level of blood lactate immediately after TCC practice was 3.8 mM, which reflected the level of lactate during TCC, approximated the onset of blood lactate accumulation (OBLA). The results demonstrate that TCC is an exercise with moderate intensity, and is aerobic in nature.

Adult↗

Bone morphogenetic protein-6 reduces ischemia-induced brain damage in rats.

BACKGROUND AND PURPOSE: Bone morphogenetic protein-6 (BMP6) and its receptors are expressed in adult and fetal brain. Receptors for BMP6 are upregulated in adult brain after injury, leading to the suggestion that BMP6 is involved in the physiological response to neuronal injury. The purpose of this study was to determine whether there was a neuroprotective effect of BMP6 in vivo and in vitro. METHODS: Lactate dehydrogenase and microtubule-associated protein-2 (MAP-2) activities were used to determine the protective effect of BMP6 against H(2)O(2) in primary cortical cultures. The neuroprotective effects of BMP6 were also studied in chloral hydrate-anesthetized rats. BMP6 or vehicle was injected into right cerebral cortex before transient right middle cerebral artery (MCA) ligation. Animals were killed for triphenyl-tetrazolium chloride staining, caspase-3 immunoreactivity and enzymatic assays, and TUNEL assay. A subgroup of animals were used for locomotor behavioral assays. RESULTS: Application of H(2)O(2) increased lactate dehydrogenase activity and decreased the density of MAP-2(+) neurons in culture. Both responses were attenuated by BMP6 pretreatment. Complementary in vivo studies showed that pretreatment with BMP6 increased motor performance and generated less cerebral infarction induced by MCA ligation/reperfusion in rats. Pretreatment with BMP6 did not alter cerebral blood flow or physiological parameters. There was decreased ischemia-induced caspase-3 immunoreactivity, caspase-3 enzymatic activity, and density of TUNEL-positive cells in ischemic cortex in BMP6-treated animals. CONCLUSIONS: BMP6 reduces ischemia/reperfusion injury, perhaps by attenuating molecular events underlying apoptosis.

Animals↗

The relationship between exercise performance and peripheral circulation in patients with peripheral arterial occlusive disease.

The exercise performance of patients with peripheral arterial occlusive disease was often impaired. The relationship of exercise performance, daily physical activity, and peripheral circulation was studied. Twenty-five patients with peripheral arterial occlusive disease were recruited; their exercise performance was evaluated with a maximal graded exercise test. A habitual physical activity questionnaire was used to quantify the physical activity level. Measurement of peripheral circulation included the assessment of macrocirculation (ankle-brachial pressure index, calf blood flow by impedance plethysmograph) and microcirculation (cutaneous blood flow, cutaneous temperature, transcutaneous oxygen tension, and cutaneous blood flow responses to iontophoresis). Pearson's product correlation coefficient and multiple linear regression were used in data analysis. Results showed that age, sports index in habitual physical activity questionnaire, and ankle-brachial pressure index were significantly correlated with maximal walking time. Age and sports index were the two major determinants for their exercise performance and accounted for a 61.5% variability.

Arterial Occlusive Diseases↗

[Differential accumulation of the new high-affinity phosphate transporter candidated gene fragment in rice roots in response to phosphorus deficiency stress].

Phosphate is a major constraint to crop production, and phosphate uptake in plant is mainly by high-affinity phosphate transporter under phosphate deficiency condition. Using RT-PCR, a 1,178 bp phosphate transporter gene fragment OjPT1 was cloned from roots of Jingxi17 (Oryza sativa L. ssp. japanica) supplied with no phosphate. The comparison of this sequence with ones in GenBank indicated that it shared about 70% similarity at amino acid level with other phosphate transporters in higher plants, such as Arabidopsis thaliana, potate, tamato, Medicago truncatula and Catharanthus roseus, and high similarity with phosphate transporters in Saccharomyces cerevisiae and Neurospora crassa. RT-PCR assay showed that the OjPT1 transcripts were induced under phosphate deficiency condition. This gene fragment OjPT1 has been deposited in GenBank (accession No. AF249619).

Amino Acid Sequence↗

[Microsatellite marker analysis of a soybean recombinant inbred line NJRIKY].

The prerequisite of genomic research such as genetic mapping is construction of a suitable segregating population and its reasonable evaluation before use. A recombinant inbred line (RILs), NJRIKY, was constructed through a cross between Kefeng 1 and Nannong 1138-2. The present study was focused on evaluation of genetic structure of the RILs through the simple sequence repeats (SSRs) analysis. A total number of 138 pairs of SSRs primers covering the whole soybean genome were randomly selected for polymorphic analysis between two parents. 86 pairs of which were polymorphic and polymorphic rate is up to 62.32%. 90 polymorphic loci were found. Further analysis with polymorphic SSRs loci on the sampled lines indicated that not only segregation of most SSRs loci conformed to the ratio of 1:1, but also almost each sampled line tended to homozyge. The distribution of genotypic composition was normal. The population is ideal for genetic mapping and other genomic research.

Microsatellite Repeats↗

Disability-adjusted life years for breast cancer patients in Taiwan.

BACKGROUND AND PURPOSE: The incidence and mortality of breast cancer in Taiwan have increased rapidly in the past several decades, but the societal impact of deaths and disabilities due to breast cancer has not been assessed. This study estimated the disability-adjusted life years (DALYs) for breast cancer patients during 1994, and compared the results with similar data from other areas of the world. METHODS: DALYs for breast cancer patients in Taiwan were calculated using the equation developed by Murray and Lopez. The incidence and mortality of breast cancer and the population structure were obtained from national statistics maintained by the Department of Health and the Ministry of the Interior. The age-specific mean survival time for breast cancer patients was estimated using the exponential distribution from incidence-mortality linkage of the incidence file at National Taiwan University Hospital and the National Mortality File maintained by the Department of Health. RESULTS: There were 11,963 years of life lost (YLL) due to breast cancer during 1994, 2677 years lived with disability (YLD), and 14,640 DALYs. The YLL and DALYs per 1000 population (1.17 and 1.44) were in the middle of the world spectrum, while the YLD value per 1000 population (0.26) was closer to those of developed countries. The proportion of DALYs contributed by younger patients (< 45 years) was higher than in developed countries and similar to those in developing countries other than Sub-Saharan Africa. The DALYs per 1000 population of women younger than 45 years of age in Taiwan were also higher than those in India, China, other regions of Asia and Islands, Sub-Saharan Africa, and the Middle Eastern Crescent. CONCLUSIONS: The disability portion (YLD) of the DALYs for breast cancer patients in Taiwan was higher than in other regions of the world. Moreover, patients younger than 45 years contributed a higher proportion of DALYs than in developed countries. The DALY value per 1000 population younger than 45 years of age was also higher than in developing countries. These results suggest that health professionals should focus more attention on programs for education, screening, and treatment of younger women.

Adolescent↗

[Phylogenetic analysis of interspecies in genus Glycine through SSR markers].

The genetic diversity among 11 species of genus Glycine (altogether 37 accessions) was evaluated through SSR analysis. The number of alleles in different loci ranges from 6 to 29, averaging 15.9 per locus; alleles of subgenus soja account for 71.5% of those in subgenus Glycine, and the fingerprinting among subgenus Glycine is more divergent than that of subgenus soja. Principal factor analysis shows that the first and the second principal factor can classify genus Glycine into two groups which represent subgenus Glycine and subgenus soja. The results of UPGMA indicate that G. mas, G. soja and G. gracilis in subgenus soja are different species.

Alleles↗

[Cloning and characterization of CMO gene from Atriplex hortensis].

Glycine betaine is a widespread osmopretectant existed in many organisms. In higher plant, glycine betaine is synthesized via a two-sep oxidation reaction: choline-->betaine aldehyde-->glycine betaine. The first step, also the speed-limiting step, is catalyzed by choline monooxygenase(CMO). Choosing halophyte Atriplex hortensis as material, we constructed a salt stress-induced cDNA library, and isolated a 1.77 kb length cDNA clone with spinach CMO cDNA as probe. The sequencing result showed a complete Open Reading Frame encoding a 438-amino-acid polypeptide which was 81% and 72% identified to CMO sequences of spinach and sugar beet in amino acid homology respectively. Compared with the CMO from spinach and sugar beet, the AhCMO had one conserved Rieske-Type [2Fe-2S] cluster-binding region and one conserved mononuclear Fe-binding motif. The expression pattern of AhCMO under salt stress was also stuied, the transcriptional level of AhCMO raised about three folds after the plant was treated with brine for 4 days. The AhCMO was then transfered into tobacco(Nictiana tabacum var. Xanthi) with 35S promotor and seven transgenic plants were certified by northern blot, these plants displayed some salt- and drought-stress tolerance when grew well on MS medium contained 1.2% NaCl or 10% PEG while the control was stagnated under the same cndition.

Amino Acid Sequence↗

Anterior pituitary failure (panhypopituitarism) with balanced chromosome translocation 46,XY,t(11;22)(q24;q13).

Hypopituitarism is the clinical syndrome that results from failure of the anterior pituitary gland to produce its hormones. Hypopituitarism can result from: (1) intrinsic or primary pituitary disease; (2) intrinsic hypothalamic or secondary pituitary disease; or (3) extrinsic extrasellar or parasellar disease. The etiologies of primary hypopituitarism are miscellaneous. The dominant clinical picture of hypopituitarism in the adult is that of hypogonadism. Reports have associated hypopituitarism with anti-pituitary-antibodies, hereditary syndrome and chromosome defects, but hypopituitarism has rarely been associated with balanced chromosome translocation (11;22)(q24;q13). Here, we describe a case of anterior pituitary failure with balanced chromosome translocation. A 19-year-old Chinese teenager presented with failure of pubertal development and sexual infantilism. On examination, the patient had the classic appearance of hypogonadism. Endocrine studies and three combined pituitary function tests revealed panhypopituitarism. A chromosomal study revealed 46,XY,t(11;22)(q24;q13), a balanced translocation between 11q24 and 22q13. Chest films showed delayed fusion of bilateral humeral head epiphyses and bilateral acromions. Scrotal sonography revealed testes were small bilaterally. Magnetic resonance imaging (MRI) of the sella revealed pituitary dwarfism. The patient received 19 months replacement therapy, including steroids (prednisolone 5 mg each day), L-thyroxine (Eltroxin 100 ug each day), and testosterone enanthate 250 mg every two weeks. His height increased 4 cm with secondary sexual characteristics developed, and muscle power increased.

Adult↗

Formation of unusual glutamate conjugates of 1-[3-(aminomethyl)phenyl]-N-[3-fluoro-2'-(methylsulfonyl)-[1,1'-biphenyl]-4-yl]-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (DPC 423) and its analogs: the role of gamma-glutamyltranspeptidase in the biotransformation of benzylamines.

The role of gamma-glutamyltranspeptidase (GGT) in transferring glutamate from endogenous glutathione (GSH) to the benzylamine moiety of a compound, such as 1-[3-(aminomethyl)phenyl]-N-[3-fluoro-2'-(methylsulfonyl)-[1,1'-biphenyl]-4-yl]-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (DPC 423), is described. Studies were performed with structurally related analogs of DPC 423 to demonstrate that this type of reaction was common to compounds possessing a benzylamine group. Synthesizing appropriate standards and confirming by liquid chromatography (LC)/mass spectroscopy and LC/NMR made unambiguous assignments of the structures of glutamate conjugates of DPC 423. The use of stable isotope-labeled GSH for metabolism studies has not been described before. In the present study, we report the novel use of deuterated GSH in conjunction with mass spectral analysis to demonstrate the glutamate transfer to the benzylamines in the presence of GGT. To further demonstrate that the alpha protons on the benzylamines and glutamate (as part of glutathione) were unaffected during the transpeptidation, these protons were replaced with deuterium. Acivicin (AT-125), a potent and selective inhibitor of GGT, was used to abolish the formation of the glutamate conjugates of DPC 423 in vitro and in vivo. This provided further evidence of the role of GGT in forming the glutamate conjugates of benzylamines. This study demonstrated conclusively that GGT was responsible for mediating the transfer of glutamic acid from GSH to the benzylamine moiety of a series of structurally related compounds.

Animals↗

[QTLs mapping of some agronomic traits of soybean].

A recombinant inbred population of soybean was developed from a intraspecies cross of Kefeng1 and Nannong 1138-2. A genetic linkage group of soybean genome was constructed, which composed of 22 linkage groups, included 302 loci, covered 2,363.8 cM. The interval mapping was used to identify quantitative trait loci (QLTs) associated with ten important agronomic traits in the RIL population. The results indicated that thirty-four QTLs were detected for the ten traits associated with yield and seed quality. We conclude that QTL analysis offers a useful tool for the genetic improvement of soybean cultivars.

Chromosome Mapping↗

Selective vulnerability of embryonic cell populations to ethanol-induced apoptosis: implications for alcohol-related birth defects and neurodevelopmental disorder.

BACKGROUND: Ethanol-induced cell death has been characterized in very few stages of embryogenesis. This investigation comprehensively maps patterns of both programmed and ethanol-induced cell death in the central nervous system and craniofacial region at 0.5-day intervals from gestational day (GD) 6.5 to 11 in mice. METHODS: A teratogenic dosage of ethanol (2.9 g/kg) or vehicle was administered via two intraperitoneal injections to pregnant C57BL/6J mice at various stages of gestation. Cell death patterns were characterized using Nile blue sulfate vital staining and histological analysis of plastic sections. Confocal laser scanning microscopy of LysoTracker Red-stained specimens allowed for three-dimensional visualization of areas of apoptosis and precise sectional imaging of mouse embryos. Apoptosis was also documented using a TUNEL technique on histological sections. RESULTS: Normal programmed cell death in control embryos was noted in the prechordal plate region at GD 8, the neuroepithelium of the fourth ventricle and anterior neuropore at GD 9, and within the ganglia of cranial nerves V, VII-VIII, IX, and X at GD 10. Acute maternal ethanol administration 12 hr before examination resulted in a dramatic increase in apoptosis within sites of programmed cell death in the embryo. Moreover, ethanol-exposed specimens exhibited stage-dependent excessive cell death in other distinct cell populations, particularly within the developing central nervous system. Ethanol-induced apoptosis was notable as follows: GD 7.5-neuroectoderm; GD 8-neural plate and primitive streak; GD 9-alar plate and presumptive neural crest of the rostral hindbrain, especially at the mesencephalon/rhombencephalon junction; GD 9.5-10-branchial arches and rhombomeres; and GD 11-diencephalon, basal ganglia, pons, and developing cerebellum. CONCLUSIONS: The results of this study revealed developmental stage-specific cell populations of the developing brain and craniofacial region that are vulnerable to ethanol-induced apoptosis and provide new insight relative to the genesis of alcohol-related birth defects.

Animals↗

Association of aflatoxin B(1)-albumin adduct levels with hepatitis B surface antigen status among adolescents in Taiwan.

Chronic hepatitis B virus (HBV) infection and aflatoxin B(1) (AFB(1)) exposure interact synergetically to induce hepatocellular carcinoma. One suggested mechanism for this interaction is the enhanced activation of AFB(1) in chronically HBV-infected individuals. Whereas no associations between chronic HBV infection and AFB(1)-albumin adducts were observed in several studies in adults, hepatitis B surface antigen (HbsAg)-positive children were found to have elevated adducts in Gambia. To assess the association between chronic HBV infection and AFB(1)-albumin adduct level in Taiwan, 200 junior high school adolescents from 20 townships were assayed for HBsAg and AFB(1)-albumin adducts. The mean AFB(1)-albumin adduct level was higher in HBsAg-positive compared with HBsAg-negative subjects. The association between HBsAg status and AFB(1)-albumin adducts remained after multivariate adjustment. This finding additionally supports the synergetic interaction between HBV and AFB(1), but the mechanism remains to be elucidated.

Adolescent↗

[Construction and analysis of a genetic linkage map of soybean].

A high-density genetic map was constructed with a RILs population (NJRIKY) from a cross of two cultivated soybean Kefeng 1 and Nannong 1138-2, using RFLP, SSR, RAPD and AFLP markers. The map consists of 24 linkage groups, which include 792 genetic markers, and covers 2,320.7 cM with an average genetic distance of 2.9 cM. The higher polymorphsims between two parents were identified with SSR markers. Due to its simplicity and stability, they could be used as anchored marker to integrate different maps constructed with different genetic markers. AFLP marker system is efficient for map construction while it easily form clusters to cause big gaps in the map. A total of 21.7% of markers was found with distorted segregation in the RILs population. The high-density molecular linkage map is fundamental for gene localization, comparative genomics, and QTL mapping of important agronomic traits.

Genetic Linkage↗

Hazardous organic matters in municipal sewage sludge in Taiwan.

Application of municipal sewage sludge to agricultural land has attracted significant attention in recent years because it conserves abundant nutrients and hydrocarbons that can be used as a soil amendment. The presence of hazardous organic matters (HOMs) in sewage sludge limits the feasibility of reuse of sewage sludge. The purpose of this study was to investigate the types and the concentrations of HOMs in municipal sewage sludge in Taiwan. An efficient SFE/GC/MS method was used to determine HOMs in sludge samples. The results indicated that di-(2-ethylhexyl) phthalate (DEHP) was persistently found in both aerobically and anaerobically digested sludges. 4-nonylphenol (4-NP) was only found in anaerobically digested sludges. Both DEHP and 4-NP have been characterized as endocrine disrupting chemicals (EDCs) or environmental endorine disruptors (EEDs). It suggested that sludges containing high levels of DEHP and 4-NP need further treatment and reduction of possible impacts on the environment before their reuse as soil fertilizers.

Agriculture↗