Search PubMed⌕ Search

Biomedical subjects

W Lu

Publications and source records attributed to W Lu.

393 records · Page 22Linked to original sources

Aminoterminal procollagen III peptide elevation in alcoholics who are selenium and vitamin E deficient.

Serum aminoterminal procollagen III peptide (PIIIP) was measured in 36 alcoholic subjects. There was a significant elevation of PIIIP in subjects with proven liver disease (median 17.5 ng/ml, n = 24) compared to those without liver disease (median 4.7 ng/ml, n = 12). Those subjects with raised serum transaminase values (AST) had elevated PIIIP values (median 13.7 ng/ml, n = 22) compared to those with normal transaminase values (median 3.7 ng/ml, n = 14). In those alcoholic subjects who were deficient in both selenium and vitamin E there was a significant elevation (p less than 0.01) of PIIIP values (median 26.4 ng/ml, n = 7) compared to subjects with normal levels (median 7 ng/ml, n = 11). Subjects deficient in selenium alone had PIIIP values in an intermediate range. Selenium and vitamin E, as important free radical scavengers, may protect the liver in alcoholic subjects from oxidative damage leading to hepatic fibrosis.

Aspartate Aminotransferases↗

Reduction in inflammatory response by prior injection of a different agent at the same site: an experimental study in the rat.

Glycogen, producing a weak PMN response, and BHI/PP, which induces a strong response, have been injected both separately and sequentially into the peritoneal cavity of the rat. It was found that the first stimulus, glycogen, had a modifying effect on the response to the second stimulus, which was reduced. Changes in the number of PMNs in the peritoneal cavity were found to correspond to PMN count changes in the blood, which were monitored simultaneously. This suggests the possibility that the number of PMNs in an exudate is dependent on blood PMN numbers. The point at which the modifying mechanism has its effect remains to be demonstrated, and an assessment of the importance of the changes in blood counts is crucial in locating the point at which the two stimuli interact.

Animals↗

Mutagenicity of benzidine and related compounds employed in the detection of hemoglobin.

Seven compounds commonly used as chromagens for the detection of hemoglobin and its derivatives have been assayed for mutagenicity employing the Salmonella/mammalian microsome test. Three of these compounds, benzidine, o-dianisidine, and o-tolidine, were shown to be mutagenic. Since benzidine and o-tolidine are already known to be carcinogens, there is a high probability that o-dianisidine will also prove to be a carcinogen. Four compounds tested with this system, o-anisidine, diphenylamine, guaicol, and o-toluidine, were not mutagenic.

Animals↗

Percutaneous implantation of a Port-Catheter System using the left subclavian artery.

PURPOSE: To evaluate the safety and feasibility of a percutaneous Port-Catheter System (PCS) implanted via the subclavian artery (SCA) for regional chemotherapy or chemoembolization of thoracic, abdominal, and pelvic malignant tumors. METHODS: Percutaneous puncture of the SCA was performed in 256 patients with thoracic, abdominal, or pelvic malignant tumors; then a catheter was inserted into the target artery. After the first transcatheter chemotherapy or chemoembolization with an emulsion of lipiodol and anticancer agents, an indwelling catheter was introduced with its tip placed in the target artery and its end subcutaneously connected to a port. RESULTS: The procedure was successfully completed in all 256 cases (100%). The indwelling catheter tip was satisfactorily placed in the target arteries in 242 cases (98%). Complications attributable to the procedure occurred in 20 (7.8%) cases, including pneumothorax (n = 10, 4%), hemothorax (n = 1, 0.4%), infections in the pocket (n = 4, 1.6%), and hematoma at the puncture site (n = 5, 2%). There were no severe sequelae or deaths. The duration of PCS usage was 1-36 months (median 9.5 months). During the course of treatment, occlusion of the target artery occurred in 20 cases (7.8%). Dislocation of the tip of the indwelling catheter occurred in 12 cases (4.7%); in 10 of the 12, the tip of the indwelling catheter was repositioned into the target artery. In all 10 cases no large symptomatic hematomas developed after the PCS was removed. CONCLUSION: Percutaneous PCS implantation via the left SCA, a relatively new procedure, is a safe and less invasive treatment approach than surgical placement for malignancies.

Abdominal Neoplasms↗

In vitro release profiles of eristostatin from biodegradable polymeric microspheres: protein aggregation problem.

Eristostatin, a low molecular weight polypeptide (MW 5725), was encapsulated within two biodegradable poly(lactic acid-glycolic acid) microspheres. In vitro release profiles from the microspheres exhibited fast initial release for up to several days, followed by very slow or no release. The later stage of the slow release was due to protein aggregation within the microspheres. A simple, noninvasive method to detect the protein aggregation within the microspheres has been developed: extraction of radiolabeled protein from the microspheres by a DC electric field into a polyacrylamide gel and subsequent exposure to a gamma-ray sensitive film. Direct application of the degrading microspheres onto the sample loading zone of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) could successfully extract the monomeric and oligomeric proteins into the autoradiogram of a gel slab, while unextractable protein aggregates within the microspheres could be directly visualized in their loading position.

Autoradiography↗

Immunohistochemical distribution of laminin-5 gamma2 chain and its developmental change in human embryonic and foetal tissues.

Immunohistochemical distribution of laminin gamma2 chain, a subunit of the basement membrane protein laminin-5, was examined in 19 cases of human embryos and foetuses ranging from 4 to 25 weeks of gestation. Laminin gamma2 was first detected in the basement membranes underlying ectodermal epithelial tissues, such as the skin and tooth, as early as 5-6 weeks of gestation. Between 6-7 and 12-13 weeks, laminin gamma2 was detected in the basement membranes of various endodermal epithelial tissues, such as the bronchus, oesophagus, stomach, intestines, urinary bladder, gallbladder and hepatopancreatic duct. The deposition of laminin gamma2 in basement membrane was associated with the process of morphogenesis. In the small intestine, laminin gamma2 first appeared in the basement membrane of the primitive short villi, and its level gradually increased in the villus region but decreased in the cryptic region during the maturation of the organ. In addition, non-basement membrane immunoreactivity for laminin gamma2 was detected in some mesoderm-derived tissues, such as the cartilage and skeletal and smooth muscle fibres. These results suggest a common role of laminin-5 and some specific roles of its gamma2 chain in the morphogenesis of human tissues.

Basement Membrane↗

Effects of lifelong ethanol consumption on rat locus coeruleus.

The effects of lifelong ethanol consumption and ageing on the morphology of locus coeruleus (LC) were studied in alcohol-preferring AA (Alko Alcohol) rats of both sexes. Ethanol (12% v/v) was the only available liquid for the ethanol-consuming rats from 3 months up to 24 months of age. Young (3-month-old) and old (24-month-old) control groups were included in the measurements. The LC morphometry was performed by an unbiased disector method. In the old control rats, the total neuron number, neuronal density and the volume of the LC proper did not differ from the young controls. In the ethanol-exposed rats, the total neuron number of the LC was decreased by 30% and the LC neuronal density by 22%, compared to the age-matched controls. No gender difference was found in the vulnerability of LC neurons to ethanol-induced degeneration. The results suggest a remarkable sensitivity of the LC neurons to the ethanol-induced degeneration in both male and female rats. The possible mechanisms and functional implications of this neuronal loss are discussed.

Aging↗

Chiari osteotomy and shelf augmentation in the treatment of hip dysplasia.

The clinical and radiographic results of Chiari osteotomy and shelf augmentation for acetabular dysplasia in 30 hips were reported. The average age at operation was 17 years for Chiari osteotomy and 13.8 years for shelf augmentation. The mean follow-up was 7.1 years for Chiari osteotomy and 4.1 years for shelf augmentation. Of the 14 Chiari osteotomies, 12 had good results by Tonnis clinical grading and 2 had poor results. There were significant improvements in the radiographic parameters measured (p < 0.01). They included center-edge angle of Wiberg, the acetabular angle of Sharp, the percentage of femoral head coverage, and the "c/b" ratio. For the 16 shelf augmentations, there were 8 good, 2 fair, and 6 poor results. The radiographic parameters measured were also all significantly improved (p < 0.01). The final Severin grading of the hips were improved by both Chiari osteotomy and shelf augmentation.

Acetabulum↗

Protein release from poly(lactic-co-glycolic acid) microspheres: protein stability problems.

The enzyme, carbonic anhydrase, has been incorporated within poly(lactic-co-glycolic acid) microspheres using a double emulsion and solvent evaporation technique. The protein stability problems during the microsphere formulation procedure and during the release period were examined in relation to the protein release kinetics over a 2 month period. Different protein release profiles could be obtained depending on the polymers used. The protein release kinetics exhibited an initial fast release followed by a slow release, resulting in an incomplete protein release although the microspheres degraded significantly. The very slow release kinetics were attributed to the protein aggregation and non-specific adsorption within the microspheres. It was found that the protein was significantly denatured and aggregated during the double emulsion formulation step. Several excipients such as albumin, poly(ethylene oxide), Pluronic F-127, and gelatin, which were loaded along with the protein within microspheres, demonstrated better protein release kinetics partly due to an increase in the protein stability. The released protein from these fast degrading microspheres, however, was severely hydrolyzed and lost its catalytic activity, caused by the accumulation of degradation products in the medium.

Carbonic Anhydrases↗