Search Results - (Author, Cooperation:V. Wong)

2018-11-30

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Geosciences

Computer Science

Medicine

Natural Sciences in General

Physics

Biochemistry, Online Only

2012-09-04

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Cell Membrane/chemistry/metabolism ; Chitin Synthase/metabolism ; Detergents ; Endoplasmic Reticulum/metabolism ; Golgi Apparatus/metabolism ; Mass Spectrometry ; Membrane Proteins/analysis/chemistry/*metabolism ; Protein Binding ; Protein Interaction Mapping ; *Protein Interaction Maps ; Proteome/analysis/chemistry/metabolism ; Saccharomyces cerevisiae/chemistry/cytology/*metabolism ; Saccharomyces cerevisiae Proteins/analysis/chemistry/*metabolism

2018-01-03

The Federation of American Societies for Experimental Biology (FASEB)

0892-6638

1530-6860

Biology

1471-0528

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1471-0528

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Summary. Zinc concentration in serum and hair was measured in a cross-sectional study of 437 Chinese women of whom 310 were normal controls studied at various stages of pregnancy and up to 12 months after delivery. The rest had spontaneous abortions, fetuses with a birthweight below the 10th centile for gestation or congenital abnormalities. Zinc concentration fell throughout normal pregnancy, the fall being greater in serum than in hair. There was no correlation between serum and hair levels. The infant birthweight had a positive correlation with serum level but a negative correlation with hair level. Abortion, low birthweight and congenital abnormality were not associated with low concentrations of zinc in plasma or hair.

Electronic Resource

1471-0528

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Summary. Forty-six hydropic infants with homozygous α-thalassaemia born during a period of 10 years have been reviewed. The incidence was 1: 1550 total births, and accounted for 81% of all non-immune hydrops. The male to female ratio was 1: 1.4. There was increased incidence of anaemia, pregnancy induced hypertension, antepartum haemorrhage, malpresentation, prematurity, fetal distress, difficult vaginal delivery, caesarean section, retained placenta. postpartum haemorrhage and congenital abnormalities. Antenatal diagnosis by DNA hybridization with subsequent abortion of the affected fetuses is the best method to decrease maternal morbidity and to reduce the incidence of hydrops fetalis in couples at risk. For those with no previous history, but with early onset hypertension and/or polyhydramnios, sonography is useful in making an earlier diagnosis, and in reducing avoidable morbidity, because DNA analysis can be done before caesarean section and aggressive neonatal management is instituted.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

The ability to preserve a grating profile during epitaxial overgrowth is vital to the design and operation of devices such as planar waveguide-coupled Bragg-resonant filters. Intentional preservation of rectangular-patterned InP gratings during gas source molecular beam epitaxial overgrowth has been accomplished. The use of a low temperature atomic hydrogen-assisted oxide removal technique alleviates the dependence on elevated temperatures for desorption of the native oxide, and is crucial to the preservation of the patterned profile. Confirmation of the overgrown grating fidelity is demonstrated via scanning electron microscopy and triple axis x-ray diffractometry. © 1997 American Institute of Physics.

Electronic Resource

1749-6632

Blackwell Publishing Journal Backfiles 1879-2005

Natural Sciences in General

Electronic Resource

1089-7666

AIP Digital Archive

Physics

Following the dynamic subgrid-scale (SGS) modeling developed by Germano et al. [Phys. Fluids A 3, 1760 (1991)] and Lilly [Phys. Fluids A 4, 633 (1992)], a multidimensional statistical-dynamic closure method for the linear or nonlinear anisotropic representation of the SGS stresses is proposed. This method converts all previously prescribed SGS model coefficients for turbulent flows to nonsingular and self-determined parameters, and in principle it does not share most deficiencies of the Smagorinsky formulation for SGS eddy viscosity. During large-eddy simulations, the SGS representation will be locally and dynamically adjusted to match the statistical structure of the resolved turbulent eddies.

Electronic Resource

1089-7666

AIP Digital Archive

Physics

Two dynamic subgrid-scale (SGS) closure methods for turbulent thermal convection are described. The first method assumes the dissipation rate equals the SGS energy production rate that includes a troublesome buoyancy term, while the second method avoids this complication with a simplifying scale analysis. Tests with large-eddy simulations (LES) of thermal convection reveal that the second method is computationally efficient, and produces results agreeing with direct numerical simulation (DNS) data, as well as values predicted by the inertial subrange theory. Within the LES, the SGS representation is locally and dynamically adjusted to match the statistical structure of the smallest resolvable eddies.

Electronic Resource

1365-2036

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background : Non-alcoholic fatty liver disease is an important cause of chronic hepatitis and cryptogenic cirrhosis. The natural history of non-alcoholic fatty liver disease is not well understood especially in Asian populations.Aim : To investigate the histological progression in Chinese patients with biopsy-proven non-alcoholic fatty liver disease.Methods : Chinese patients who had liver biopsy at least 3 years ago and confirmed to have non-alcoholic fatty liver disease were invited for a second liver biopsy. Clinical and laboratory parameters related to their liver function and metabolic syndrome were recorded and analysed. Liver biopsies were scored for the degree of steatosis, necroinflammation and fibrosis. Correlation coefficients were calculated to assess the association between changes in histological scores and metabolic parameters.Results : Seventeen patients who had been followed up for a median period of 6.1 (range: 3.8–8.0) years underwent a second liver biopsy. Nine (53%) patients had progressive disease with worsening of fibrosis score. No statistically significant correlation was found between the changes in histological scores and metabolic parameters. Seven patients developed hypertension or diabetes mellitus during the period of follow-up.Conclusions : Non-alcoholic fatty liver disease is a progressive disease in Chinese patients as in their Caucasian counterparts. Diagnosis of non-alcoholic fatty liver disease may predate development of new components of metabolic syndrome.

Electronic Resource

1365-2036

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Heparin, a group of sulphated glycosaminoglycans, in addition to its anticoagulant activity, has a wide range of potentially anti-inflammatory effects. These include inhibition of neutrophil elastase and inactivation of chemokines. Previous reports of fortuitous improvement in ulcerative colitis patients treated with heparin for prophylaxis of venous thrombosis, prompted us to perform a pilot study in patients with corticosteroid-resistant ulcerative colitis.〈section xml:id="abs1-2"〉〈title type="main"〉Methods:Sixteen hospitalized patients in relapse from ulcerative colitis and unresponsive to high-dose corticosteroid therapy were treated with intravenous standard heparin (subcutaneous in two patients), the dose was adjusted to provide standard anticoagulant activity. Five patients continued with subcutaneous injections on discharge, with a gradual reduction in the frequency of doses.〈section xml:id="abs1-3"〉〈title type="main"〉Results:Within 1 week of starting heparin, 12/16 patients had shown a considerable reduction in stool frequency. After 2 weeks of heparin therapy median stool frequency had improved from 8.0/day (range 6.3–10.0) pre-treatment to 3.5/day (2.5–5.25) (P=0.008), and by 4 weeks 12/16 achieved clinical remission. Four patients required elective colectomy. Three patients were treated with heparin on a second occasion during a relapse, two failed to respond and required subsequent colectomy. Nine remain well. No serious complications were seen due to the anticoagulant activity, apart from bruising at subcutaneous injection sites.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusion:The response to heparin in patients with ulcerative colitis resistant to standard therapy is encouraging and supports the previous uncontrolled evidence for a therapeutic effect. A controlled trial of heparin in ulcerative colitis is clearly indicated.

Electronic Resource

1365-2036

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background : Non-alcoholic fatty liver disease is prevalent in affluent countries and is a cause of cirrhosis and possibly hepatocellular carcinoma.Aim : To examine the clinical and histological features of biopsy-proven non-alcoholic fatty liver disease and investigate the predictors of severe histological disease in Chinese patients.Methods : Electronic records of all patients (n = 247) who underwent liver biopsy between 1996 and 2003 in our hospital were retrieved. Patients who had histological features of non-alcoholic fatty liver disease were identified. The demographic, clinical, laboratory and histological (Brunt's criteria) parameters of these patients were analysed.Results : Forty-two patients had histology-proven non-alcoholic fatty liver disease. The median age was 47 years (range 23–69). All except one patient had features of metabolic syndrome. The median alanine aminotransferase was 93 (range 24–270) IU/L. Thirty-six (85.7%) patients had steatohepatitis and 11 (26.1%) also had fibrosis. Only one patient had stage 3 fibrosis. The presence of diabetes mellitus predicted higher grade steatohepatitis and fibrosis (P = 0.019) whereas alanine aminotransferase level had no correlation with histological severity of steatohepatitis. After a median follow-up of 42 months, no patient developed hepatic decompensation.Conclusions : Most Chinese patients with non-alcoholic fatty liver disease had features of the metabolic syndrome. Histological activity was generally mild. Diabetes mellitus was the most important predictor of severe histological disease.

Electronic Resource

1365-2036

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background : The efficacy of lamivudine therapy in chronic hepatitis B is well established. However, drug-resistant YMDD mutants emerge with extended therapy. This may result in the resurgence of viral replication, the return of hepatitis and histological deterioration.Aim : To study the safety of stopping lamivudine when the drug is no longer effective.Methods : In the 5-year Asian Lamivudine Study, 34 patients from a single centre were included in this study. They had harboured YMDD mutants for at least 2 years. Lamivudine was discontinued and they were followed up at regular intervals. Clinical symptoms, liver biochemistry and viral serology were monitored.Results : In a median follow-up of 20 months after stopping lamivudine (range, 7–39 months), 20 of the 34 patients (58.8%) had elevated alanine aminotransferase (ALT), 13 patients (38.2%) had elevated ALT one to five times the upper limit of normal and seven patients (20.6%) had an ALT flare (ALT more than five times the upper limit of normal with detectable hepatitis B virus DNA). There was no liver decompensation. ALT flare could be predicted by ALT over twice the upper limit of normal at the time of stopping lamivudine (P = 0.037).Conclusions : It is relatively safe to stop lamivudine after YMDD mutants have emerged. ALT levels greater than or equal to twice the upper limit of normal at the time of stopping lamivudine have a higher risk for ALT flare.

Electronic Resource

0005-2760

Chemical shift anisotropy ; DPPC ; Lung surfactant ; NMR ; POPG ; Phase property

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Medicine

Physics

Electronic Resource

0012-1606

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Electronic Resource

1433-2965

Bisphosphonate toxicity ; Esophagitis ; Osteoporosis ; Pamidronate

Springer Online Journal Archives 1860-2000

Medicine

Abstract Pamidronate (aminohydroxypropylidine bisphosphonate, APD) is an effective agent for treatment of Paget's disease of bone, and it has also been thought to be effective for treatment of osteoporosis. We desired to study a newer, time-release preparation of pamidronate, and carried out a placebo-controlled, double-masked study of postmenopausal osteoporosis. The original formulation was in a rapidly dissolving gelatin capsule. We encountered four episodes of esophagitis in 49 enrolled patients. We therefore discontinued treatment with this preparation and later began the study again using a standard tablet preparation. We encountered an additional case of erosive esophagitis in 1 patient of 40 receiving this tablet preparation. No patient was receiving concomitant medication which could cause esophagitis. Two of the patients gave a past history of hiatal hernia and 1 gave a history of gastric ulcer 27 years previously. The diagnosis of esophagitis was confirmed in all cases by endoscopy. Healing of the esophagitis promptly ensued after discontinuation of the pamidronate and the use of antacid medication.

Electronic Resource

1436-5065

Springer Online Journal Archives 1860-2000

Geography

Physics

Summary  A completely new nonhydrostatic model system known as the Advanced Regional Prediction System (ARPS) has been developed in recent years at the Center for Analysis and Prediction of Storms (CAPS) at the University of Oklahoma. The ARPS is designed from the beginning to serve as an effective tool for basic and applied research and as a system suitable for explicit prediction of convective storms as well as weather systems at other scales. The ARPS includes its own data ingest, quality control and objective analysis packages, a data assimilation system which includes single-Doppler velocity and thermodynamic retrieval algorithms, the forward prediction component, and a self-contained post-processing, diagnostic and verification package. The forward prediction component of the ARPS is a three-dimensional, nonhydrostatic compressible model formulated in generalized terrain-following coordinates. Minimum approximations are made to the original governing equations. The split-explicit scheme is used to integrate the sound-wave containing equations, which allows the horizontal domain-decomposition strategy to be efficiently implemented for distributed-memory massively parallel computers. The model performs equally well on conventional shared-memory scalar and vector processors. The model employs advanced numerical techniques, including monotonic advection schemes for scalar transport and variance-conserving fourth-order advection for other variables. The model also includes state-of-the-art physics parameterization schemes that are important for explicit prediction of convective storms as well as the prediction of flows at larger scales. Unique to this system are the consistent code styling maintained for the entire model system and thorough internal documentation. Modern software engineering practices are employed to ensure that the system is modular, extensible and easy to use. The system has been undergoing real-time prediction tests at the synoptic through storm scales in the past several years over the continental United States as well as in part of Asia, some of which included retrieved Doppler radar data and hydrometeor types in the initial condition. As the first of a two-part paper series, we describe herein the dynamic and numerical framework of the model, together with the subgrid-scale turbulence and the PBL parameterization. The model dynamic and numerical framework is then verified using idealized and realistic mountain flow cases and an idealized density current. Other physics parameterization schemes will be described in Part II, which is followed by verification against observational data of the coupled soil-vegetation model, surface layer fluxes and the PBL parameterization. Applications of the model to the simulation of an observed supercell storm and to the prediction of a real case are also found in Part II. In the latter case, a long-lasting squall line developed and propagated across the eastern part of the United States following a historical number of tornado outbreak in the state of Arkansas.

Electronic Resource

1432-0878

Tracheal epithelium (human, animal) ; APUD-Endocrine system ; Electron microscopy ; Histochemistry

Springer Online Journal Archives 1860-2000

Biology

Medicine

Summary This study describes distinctive cells with ultrastructural and histochemical features of APUD-type endocrine cells within the tracheal epithelium of human fetuses, newborns and children as well as different animal species. These cells referred to as Kultschitzky cells (K cells) were found to be argyrophilic, but not argentaffin, and are considered analogous to the same type of cells in lung and gastro-intestinal tract. Fluorescence histochemistry demonstrated the presence of intracellular amine within tracheal K cells, but only after in-vitro or in-vivo administration of amine precursor (L-DOPA). Ultrastructurally, these cells are characterized by the presence of numerous cytoplasmic granules (dense core vesicles) which show species related morphologic variations. Two different types of K cells were found in trachea of lamb and armadillo, each type possessing morphologically different dense core vesicles. In human and rabbit tracheas, only one type of K cell was identified. K cells in the trachea are distributed as single cells between other epithelial cells; neuroepithelial bodies such as those found in bronchial mucosa were not identified. Well differentiated K cells were found in tracheas of early human fetuses and throughout gestation, infancy, and childhood. Preservation of K cells in human autopsy material and widespread occurrence of these cells in various laboratory animals will permit further studies into the nature and function of tracheobronchial endocrine cells.

Electronic Resource

1432-0878

Lung (fetal rabbit) ; Neuro-epithelial bodies ; Organ culture ; Reserpine ; Ca+ + ionophore A-23187

Springer Online Journal Archives 1860-2000

Biology

Medicine

Summary Lung explants from fetal rabbits at the late glandular stage of development (20 days' gestation) and near term (31 days' gestation) were maintained in organ culture for up to 22 days. They were studied by light and electron microscopy to determine whether neuro-epithelial bodies (NEB) of the lung retain structural integrity in vitro. Cultured NEB retained argyrophilia and specific amine fluorescence after formaldehyde condensation. Their ultrastructural morphology showed some differences from that of uncultured NEB: the terminal axons had degenerated and the secretory granules (dense-core vesicles, DCV) were slightly larger, more pleomorphic, more electron-dense, and redistributed throughout the cytoplasm rather than being confined chiefly to the basal regions. These changes, together with hypertrophy of Golgi zones, suggest increased synthesis and storage of secretory products in the DCV during culture. In NEB from near-term expiants cultured for 7 days and incubated with reserpine, the core of DCV decreased in size and electron-density and became finely granular, a sign of amine release. Ca++ ionophore # A-23187, also, induced changes in the ultrastructure of DCV, suggesting that the secretory process in lung neuro-endocrine cells, as in other secretory cells, is Ca++-dependent.

Electronic Resource