PubMed Health⌕ Search

Biomedical subjects

S P Hu

Publications and source records attributed to S P Hu.

17 recordsLinked to original sources
PubMed2005

Grain yield responses to moisture regimes in a rice population: association among traits and genetic markers.

Drought is a major constraint to rice (Oryza sativa L.) production in rainfed and poorly irrigated environments. Identifying genomic regions influencing the response of yield and its components to water deficits will aid our understanding of the genetic mechanism of drought tolerance (DT) of rice and the development of DT varieties. Grain yield (GY) and its components of a recombinant inbred population developed from a lowland rice and an upland rice were investigated under different water levels in 2003 and 2004 in a rainout DT screening facility. Correlation and path analysis indicated that spikelet fertility (SF) was particularly important for grain yield with direct effect (P=0.60) under drought stress, while spikelet number per panicle (SN) contributed the most to grain yield (P=0.41) under well-watered condition. A total of 32 quantitative trait loci (QTLs) for grain yield and its components were identified. The phenotypic variation explained by individual QTLs varied from 1.29% to 14.76%. Several main effect QTLs affecting SF, 1,000-grain weight (TGW), panicle number (PN), and SN were mapped to the same regions on chromosome 4 and 8. These QTLs were detected consistently across 2 years and under both water levels in this study. Several digenic interactions among yield components were also detected. The identification of genomic regions associated with GY and its components under stress will be useful to improve drought tolerance of rice by marker-aided approaches.

Chromosome Mapping↗
PubMed2005

The role of high-frequency jet ventilation in the treatment of Cheyne-Stokes respiration in patients with chronic heart failure.

BACKGROUND: Cheyne-Stokes respiration with central sleep apnea (CSR-CSA) is common in patients with severe cardiac failure. Various modes of positive airway pressure have been suggested as treatments. The authors hypothesized that high frequency jet ventilation (HFJV) can improve central sleep apnea in patients with chronic heart failure. METHODS: Eleven subjects with stable, optimally treated chronic heart failure and Cheyne-Stokes respiration were tested untreated and on four treatment nights in random order: nasal oxygen (4 L/min), continuous positive airway pressure (CPAP) (mean 9.3 cm H(2)O), bilevel positive airway pressure (BiPAP)(mean 12.0/5.3 cm H(2)O), or HFJV(60 approximately 80 breaths per minute) during polysomnography (EMBLA, Flaga, Reykjavik, Iceland). RESULTS: The apnea-hypopnea index (AHI) declined from 30.9 +/- 8.3/h in untreated night to 23.6 +/- 6.6/h oxygen night and 18.5 +/- 5.0/h CPAP, 14.3 +/- 3.9/h BiPAP, and 20.1 +/- 4.1/h HFJV (all P < 0.001 versus control). There was no significant difference between the AHI of HFJV and that of CPAP (P = 0.541). Arousal index decreased from 31.4+/-13.2/h untreated to 25.0 +/- 7.1/h oxygen and 13.6 +/- 4.7/h CPAP, to 13.7 +/- 4.9/h BiPAP and 14.4 +/- 4.7/h HFJV. HFJV had the similar effect to the other therapeutic groups in arousal index (P > 0.05). There were large increases in slow-wave and rapid eye movement (REM) sleep with HFJV. All subjects preferred HFJV to CPAP. CONCLUSIONS: One night of therapy with HFJV improved nocturnal breathing pattern and sleep quality in patients with Cheyne-Stokes respiration in chronic heart failure. HFJV therapy for sleep and breathing were the same as those during a nasal CPAP night. A long-term study of the effect of HFJV on cardiovascular function is needed.

Aged↗
PubMed2005

Further evidence for an HLA-related recessive mutation in nasopharyngeal carcinoma among the Chinese.

We typed 247 cases of nasopharyngeal carcinoma (NPC), a disease predominantly of the southern Chinese, and 274 controls from the Chao Shan region of China's Guangdong province for HLA A and B. Besides confirming the established associations with A2, A33, B46 and B58 (positive associations) and A11 (negative association), the results demonstrated a number of rarer alleles with strong negative association with NPC. Our data, combined with those from the previous studies in Southern Chinese, displayed the protective effects for A31 (odds ratio (OR)=0.0; 95% confidence interval (CI)=0-0.11), B13 (OR=0.50; 95% CI=0.35-0.69), B27 (OR=0.49; 95% CI=0.25-0.92), B39 (OR=0.18; 95% CI=0.06-0.48) and B55 (OR=0.32; 95% CI=0.14-0.68), the ORs comparing individuals with or without each allele. Other ethnic groups do not display such large HLA-associated variation in NPC risk. We show that a linked NPC gene with dominant mode of action could not generate such large protective effects. The results provide strong supporting evidence for the existence of a southern Chinese specific, recessive NPC gene closely linked to the HLA region as a major determinant of the Chinese risk for the disease.

China↗
PubMed2005

Analysis of STR polymorphisms in the Chao Shan population in South China.

Chao Shao area is a littoral under the jurisdiction of Guangdong province, abutting on Fujian. Historically, the area was relatively isolated from other parts of China until 1990s, when it started to take a small number of immigrants from other regions. People residing in this area speak in unique dialect and have distinct lifestyle. Allele frequencies for the 15 short tandem repeats (STR) loci included in the AmpFLSTR Identifiler kit were obtained from a sample of 144 unrelated Chinese born and living in the Chao Shan area, South China.

China↗
PubMed2001

Lysine-derivatized polyurethane as a clot lysing surface: conversion of adsorbed plasminogen to plasmin and clot lysis in vitro.

Polyurethane surfaces to which lysine residues are immobilized by photochemical methods are proposed as a basis for clot lysing surfaces. The lysines are attached in such a way that the epsilon-amino and carboxyl groups are free. We showed previously that these surfaces, when placed in contact with plasma, adsorb only plasminogen and virtually no other proteins (McClung et al., J. Biomed. Mater. Res. 49 (2000) 409). In this communication, data based on a chromogenic substrate assay are presented showing that plasminogen adsorbed to these surfaces is readily converted to plasmin in the presence of tissue-plasminogen activator (t-PA). Moreover, the rate of activation on the surface is considerably greater than in solution. Experiments demonstrating the ability of these surfaces to dissolve fibrin clots are also reported. Surfaces exposed to plasma and then to t-PA were placed in citrated plasma. On recalcification, clotting was initiated, but the incipient clots were soon dissolved. On control surfaces (no lysine or lysine in which the epsilon-amino groups were not available) coagulation continued until a stable clot was formed. Similar observations were made when the plasma/t-PA exposed surfaces were placed in a pure fibrinogen solution and thrombin was added.

Adsorption↗
PubMed2000

Adsorption of plasminogen from human plasma to lysine-containing surfaces.

The objective of this work is to develop blood-contacting surfaces that will dissolve nascent clots that may begin to form on them. Surfaces were prepared consisting of a polyurethane to which a coating reagent was attached covalently by photochemical methods. The coating reagent was a polyacrylamide with lysine and benzophenone (for photochemical attachment) moieties pendant to the chains. It was hypothesized that via the lysine moieties such surfaces would show specific binding affinity for plasminogen, the principal component of the fibrinolytic system in blood. Surfaces of varying lysine content in which the lysine was bound through the alpha-amino groups, leaving the epsilon-amino groups free, were investigated. A control surface in which the lysine was bound through the epsilon-amino groups was also examined. Advancing water contact angles showed the surfaces to be hydrophilic. Hydrophilicity was found to decrease as the lysine content increased. Adsorption of plasminogen from plasma was studied using radioiodinated plasminogen as a tracer. For the epsilon-lysine surfaces, adsorption increased with increasing lysine content and reached a value of 1.2 microg/cm(2) for the surface with the highest lysine content, that is, in the range expected for a compact monolayer of plasminogen. The control surfaces, which contained either no lysine or lysine in which the epsilon-amino groups were unavailable, adsorbed very small amounts of plasminogen. Immunoblots were obtained for the proteins eluted from the surfaces after incubation with plasma. For the control surfaces, most of the proteins tested for (some 20 in all) were present. However, for the surface containing the highest concentration of epsilon-lysine, only plasminogen was detected in a significant amount. It is concluded that the epsilon-lysine surface adsorbs plasminogen to the exclusion of the other plasma proteins. Studies to examine the fibrinolytic properties of these surfaces will constitute the next phase of this work.

Adsorption↗
PubMed1997

Nutrition knowledge, attitudes and practices among senior medical students in Taiwan.

OBJECTIVE: Nutrition is an important issue in medical training, but the nutritional knowledge, attitudes and practices of medical students in Taiwan have not been elucidated. METHODS: This investigation was a need assessment that examined knowledge, attitude and practices of medical students in selected areas of nutrition. A national sample of 528 senior medical students from nine medical colleges in Taiwan participated in this study by completing a questionnaire. RESULTS: On a 10-point scale, the average score of students on general and clinical nutritional knowledge was 5.99 +/- 1.51 and 5.15 +/- 1.77, respectively. The percentage of correct answers from questionnaires in both areas was 60% and 52%, respectively. Seventy-seven percent or more of the students reported that they either agreed or strongly agreed with four positive-attitude statements and either disagreed or strongly disagreed with two out of three negative-attitude statements. Between 30% and 61% of the students reported that they practice on nutrition-related individual behaviors. CONCLUSIONS: The knowledge, attitudes and practices of senior medical students in Taiwan suggest the need for education strategies to improve competence in the area of nutrition.

Adult↗
PubMed1997

Nutrition knowledge, attitude and practice among primary care physicians in Taiwan.

OBJECTIVE: To investigate nutritional knowledge, attitude and practices among primary care physicians in the Taiwan area. METHOD: A closed-end questionnaire containing 26 knowledge questions, 12 attitude statements and 12 practice statements was mailed to physicians on the mailing list of the National Health Administration (NHA). RESULTS: The data reported are based on the responses of 27% of the total 1210 primary care physicians in the Taiwan area. Physicians answered 59% of the total knowledge questions correctly, with a tendency to score higher on general knowledge than clinical nutrition. The majority of physicians tended to agree with the positive-attitude statements and disagree with the negative-attitude statements. The performance of physicians regarding personal practices was less than that for job-related practices. CONCLUSIONS: This nationwide survey of nutrition-related knowledge and practices demonstrates the need for nutrition education for physicians. The questionnaire may be a useful instrument for future educational strategies in Taiwan.

Adult↗
PubMed1996

Induction of the chemotactic S100 protein, CP-10, in monocyte/macrophages by lipopolysaccharide.

The murine S100 protein CP-10 is a potent chemotactic factor for murine and human myeloid cells in vivo and in vitro. This is the first report describing regulations of the CP-10 gene by a proinflammatory stimulus, lipopolysaccharide (LPS), in cells of the monocyte/macrophage lineage. Murine monocyte/macrophage-like WEHI 265 and RAW 264.7 cells preexposed to 5 to 50 ng/mL LPS expressed significant levels of CP-10 mRNA 4 hours, and maximal at 20 hours, after a secondary LPS challenge. This was accompanied by increasing levels of cell-associated and released CP-10 protein. In contrast, a single dose of LPS upregulated CP-10 mRNA in elicited peritoneal macrophages, whereas mRNA and protein levels decreased following LPS challenge. The state of macrophage differentiation may control responsiveness as LPS had no effect on CP-10 basal levels in bone marrow derived macrophages. LPS-induced CP-10 expression was controlled at the transcriptional level and nuclear run-on and protein synthesis inhibition assays indicated that LPS priming and challenge of RAW cells occurred via distinct pathways. MRP14, another S100 protein generally coordinately expressed with human MRP8, was not induced by LPS under the same conditions. We propose that CP-10 may play a key role in recruitment of leukocytes into tissues in response to gram-negative bacterial infection.

Animals↗
PubMed1991

Polymerase chain reaction (PCR) mutagenesis enabling rapid non-radioactive detection of common beta-thalassaemia mutations in Mediterraneans.

The IVS-1-110 (G----A) and IVS-1-1 (G----A) mutations occur in approximately 33% and 9% respectively of beta-thalassaemia alleles in Mediterraneans (Kazazian & Boehm, 1988). They are generally detected in polymerase chain reaction (PCR)-amplified material by allele-specific oligonucleotide (ASO) hybridization patterns. In this study, artificial base substitutions in amplified material have been created to distinguish normal from mutant alleles on the basis of restriction enzyme digestion patterns. Invariant target sites provide an internal control for restriction enzyme activity. Mutagenesis was achieved by 3' base mismatches in primers selected to anneal immediately adjacent to target sites. Digestion of PCR products from normal and thalassaemic alleles with the restriction enzymes MboI (IVS-1-110) and HinfI (IVS-1-1) produced different fragments on electrophoresis. The above strategy was validated by allele-specific oligonucleotide probing. Identification of the three commonest mutations in this population (IVS-1-110, codon 39 and IVS-1-1), which account for approximately 69% of thalassaemic alleles (Kazazian & Boehm, 1988), was subsequently undertaken in seven chorion villus biopsies.

Base Sequence↗
PubMed1991

Utility of the polymerase chain reaction (PCR) for prenatal diagnosis of genetic disease.

Gene amplification by the polymerase chain reaction (PCR) has been applied to prenatal diagnosis for alpha and beta thalassemias (1 and 5 cases respectively), Hemoglobin (Hb) Lepore/beta thalassemia (1 case) and cystic fibrosis (14 cases). Chorionic villus samples were obtained in the tenth week of pregnancy and DNA analysed in parallel with conventional gene mapping. Direct diagnosis of the common Mediterranean beta-thalassemia mutations (IVS-1-110 and codon 39), Hb Lepore, and the delta F508 mutation causing cystic fibrosis was achieved by hybridization of amplified material with pairs of allele-specific oligonucleotide (ASO) probes or by restriction enzyme digestion of PCR products. Results were confirmed by DNA mapping. Definitive diagnosis or exclusion of an affected fetus was possible in 17 of 21 cases thus examined. PCR reduces the time required for prenatal diagnosis. DNA contamination is a potential source of error.

Alleles↗
PubMed1986

Siderophore production by Pasteurella multocida.

Pasteurella multocida grown under conditions of iron deprivation secreted into the culture medium a growth-enhancing factor which functioned as a siderophore. The siderophore was found to be neither a phenolate nor a hydroxamate by chemical tests and bioassays and was given the trivial name multocidin. Multocidin was partially purified and found to be a highly polar, nonaromatic, and dialyzable compound. This is the first report demonstrating the production of a siderophore by P. multocida.

Culture Media↗
PubMed1980

Studies on the lysine-binding sites of human plasminogen. The effect of ligand structure on the binding of lysine analogs to plasminogen.

A method is described for measuring relative binding constants of lysine and analogs of lysine to plasminogen and plasminogen 'kringle' fragments. Plasminogen or kringle fragments adsorbed to lysine-Sepharose are eluted with increasing concentrations of lysine or other ligands, the concentration of ligand required to elute 50% of the protein being taken as a measure of the binding constant. The method is simple and is not dependent on monitoring conformational changes. We confirm earlier reports that the best ligands for the lysine binding sites of plasminogen are omega-amino acids containing five or six carbons. We show further that both Glu-plasminogen (the native form with N-terminal glutamic acid) and Lys-plasminogen (a degraded form with N-terminal lysine), as well as the heavy chain fragments, kringle 4 and kringle 1+2+3, have very similar properties with regard to binding specificity for omega-amino acids. For all species optimal binding is observed when the distance between the amino and carboxyl carbon is about 0.68 nm. The finding of ligands is decreased by the presence of polar atoms on the alpha and beta positions of the carbon chain of amino acids. Arginine binds relatively weakly at the lysine site and there does not appear to be a separate arginine binding site in plasminogen.

Binding Sites↗
PubMedDate not supplied

Surface texturing and coating of biomaterial implants: effects on tissue integration and fibrosis.

To determine whether texturing and coating have additive effects in promoting tissue integration and inhibiting fibrosis, we evaluated smooth silicone rubber (SSR), textured silicone rubber (TSR), porous silicone rubber (PSR), expanded polytetrafluoroethylene (ePTFE), and porous polyurethane (PPU) subcutaneous implants in eight minipigs. Some of the implants were coated with type IV collagen (Col) and/or fibronectin (Fn). At 6 months, we removed the implants and examined them microscopically. Texturing was more important than Col and Fn in reducing fibrosis and inflammation. The PSR yielded the best response, including reduced fibrosis and inflammation, satisfactory adherence, and no dystrophic mineralization.

Animals↗