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C Webber

Publications and source records attributed to C Webber.

51 records · Page 3Linked to original sources
PubMed1987

The immunologic detection and characterization of cartilage proteoglycan degradation products in synovial fluids of patients with arthritis.

Antibodies were used in radioimmunoassays with gel chromatography to detect the hyaluronic acid-binding region, core protein, and keratan sulfate of human cartilage proteoglycan in the synovial fluids of patients with rheumatoid arthritis, juvenile rheumatoid arthritis, and osteoarthritis. All fluids contained proteoglycan that was mainly included on Sepharose CL-4B; this result indicates cleavage of proteoglycan (which is normally excluded). The hyaluronic acid-binding region was the smallest and most commonly detected fragment. It was relatively free of keratan sulfate and core protein, and it could sometimes bind to hyaluronic acid. Other larger fragments containing core protein and/or keratan sulfate were detected in every fluid.

Aggrecans↗
PubMed1987

Transformation related expression of glutathione-S-transferase P in rat liver cells.

A neutral isoenzyme of glutathione transferase designated glutathione-S-transferase 7-7, but also referred to as glutathione-S-transferase P (GST-P) is absent from adult rat liver hepatocytes, but expressed at a very early stage in chemically induced in vivo hepatocarcinogenesis. The expression of this enzyme in a range of aflatoxin B1 (AFB1) associated hepatocarcinogenic systems has been examined, including in vivo induced preneoplastic and neoplastic liver tissue, cell lines derived from hepatomas, primary hepatocytes in culture and an immortalized rat liver cell line before and after transformation in vitro either by transfection with ras oncogenes or by treatment with metabolically activated AFB1. Analyses of total cytosol proteins using a polyclonal antibody to GST-P did not detect the presence of GST-P protein in cytosols from control or regenerating liver. A low level of expression was detected in the immortalized, non-transformed epithelial cell line, but a greatly induced level occurred subsequent to transformation of these cells by either of the two techniques used. High levels of the protein were detected in in vivo induced preneoplastic and neoplastic tissues, and in the cell lines derived from them. Total RNA fractions isolated from the various cells or tissues, when examined with a cDNA probe for GST-P mRNA, showed it to be absent from control and regenerating rat liver. It was present at low levels in the untransformed cell line and primary hepatocytes after 48 h in culture, but present at greatest abundance in the in vivo and in vitro transformed cells. The results indicate that the highest elevation in expression of this protein is associated with the stage of definitive malignant transformation in in vitro carcinogenesis, and this could have relevance in defining comparable events in the in vivo multistage sequence.

Aflatoxin B1↗
PubMed1987

Immunodetection and characterization of the degradation of cartilage proteoglycans in vitro and in vivo.

The large aggregating cartilage proteoglycans can be detected immunologically using antibodies directed against the hyaluronic acid-binding region, core protein, keratan sulfate, chondroitin sulfate, and hyaluronic acid. With radioimmunoassays we have detected proteoglycans released from adult human articular cartilage in vitro and in vivo. In vitro cleavage appears to occur mainly adjacent to the hyaluronic acid binding region with the release of the rest of the molecule. Two distinct populations have been observed, the larger of which is chondroitin sulfate-rich and the smaller keratan sulfate-rich. Although they are a little smaller and probably aggregate less with hyaluronic acid, these populations correspond in size and composition to two similar populations detected in situ in healthy adult human articular cartilage. In vivo studies of synovial fluid have revealed that the proteoglycan fragments are smaller and the most commonly detected fragment is the hyaluronic acid binding region. This suggests that in vivo further degradation occurs, probably due to degradation mediated by the inflamed synovium and polymorphonuclear leucocytes present in the synovial fluid of inflamed joints.

Binding Sites↗
PubMed1986

Fine-needle aspiration in the diagnosis of cervical lymphadenopathy.

The extent of workup in patients with cervical adenopathy has always been controversial. Extensive workup in the absence of a histologic diagnosis indicative of a malignant process is unwarranted. Although open biopsy may be necessary for certain benign conditions, its routine application for metastatic nodes is not advised. We have used fine-needle aspiration as a routine procedure in the initial evaluation of cervical adenopathy. Over the past 3 years, 140 needle aspirations have been performed. Adequate specimens were obtained in 97 percent of the patients and the diagnostic accuracy was 96 percent. Overall, 45 percent of the patients had the diagnosis of a malignant tumor established whereas others had benign tumors. Metastatic squamous cell carcinoma was diagnosed accurately in all of the patients. Other malignant tumors reported accurately included lymphoma, adenocarcinoma, and metastatic thyroid carcinoma. Among the benign conditions, accurate diagnoses could be established in patients with tuberculosis, chronic lymphadenitis, and hyperplastic lymph nodes. The findings of fine-needle aspiration are helpful in directing subsequent workup. If the findings do not correlate with the clinical suspicion, greater weight is given to the clinical picture and diagnostic workup appropriate for the suspected disease is performed. Proper use of fine-needle aspiration requires close communication between an experienced cytologist and the head and neck surgeon. This series demonstrates that fine-needle aspiration is a safe, accurate, and valuable tool for the evaluation of cervical adenopathy.

Adenocarcinoma↗
PubMed1986

Localization of a dermatan sulfate proteoglycan (DS-PGII) in cartilage and the presence of an immunologically related species in other tissues.

A monoclonal antibody to a core-protein-related epitope of a small dermatan sulfate-rich proteoglycan (DS-PGII) isolated from adult bovine articular cartilage (22) was used to localize this molecule, or molecules containing this epitope, in bovine articular cartilages, in cartilage growth plate, and in other connective tissues. Using an indirect method employing peroxidase-labeled pig anti-mouse immunoglobulin G, DS-PGII was shown to be present mainly in the superficial zone of adult articular condylar cartilage of the metacarpal-phalangeal joint. In fetal articular and epiphyseal cartilages, the molecule was uniformly distributed throughout the matrix. By approximately 10 months of age it was confined mainly to the superficial and middle zones of articular cartilage and the inter-territorial and pericellular matrix of the deep zone. DS-PGII was not detected in the primary growth plate of the fetus except in the proliferative zone, where it was sometimes present in trace amounts. In contrast, it was present throughout the adjacent matrix of developing epiphyseal cartilage. In the trabeculae of the metaphysis, strong staining for DS-PGII was seen in decalcified osteoid and bone immediately adjacent to osteoblasts. Staining was also observed on collagen fibrils in skin, tendon, and ligament and in the adventitia of the aorta and of smaller arterial vessels in the skin. These observations indicate that DS-PGII and/or molecules containing this epitope are widely distributed in collagenous tissues, where the molecule is intimately associated with collagen fibrils; in adult cartilage this association is limited mainly to the narrow parallel arrays of fibrils which are found in the superficial zone at the articular surface. From its intimate association and other studies, this molecule may play an important role in determining the sizes and tensile properties of collagen fibrils; it may also be involved in the calcification of osteoid but not of cartilage.

Animals↗
PubMed1985

Isolation of dermatan sulfate proteoglycans from mature bovine articular cartilages.

Two species of dermatan sulfate proteoglycans, called DS-PGI and DS-PGII, have been isolated from mature bovine articular cartilages. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis at low ionic strength in 0.01 M phosphate the dermatan sulfate proteoglycans appeared as a single polydisperse species whose molecular weight ranged from 80,000 to 140,000. The dermatan sulfate proteoglycans eluted as a single peak on Sepharose CL-4B chromatography in 4 M guanidine hydrochloride and showed no tendency to separate into two components. Following chondroitinase AC and ABC digestion, a core protein was obtained whose molecular weight was 45,000. However, what appeared to be a single dermatan sulfate proteoglycan was consistently separated into two species of distinctly different mobilities by sodium dodecyl sulfate-polyacrylamide gel electrophoresis at high ionic strength in 0.375 M Tris. The molecular weight of the smaller species (DS-PGII) ranged from 87,000 to 120,000. The molecular weight of the larger species (DS-PGI) ranged from 165,000 to 285,000. DS-PGI self-associates in 0.375 M Tris, while DS-PGII does not. This phenomenon was exploited to separate DS-PGI and DS-PGII by preparative electrophoresis on 5 to 20% gradient slab gels. The immunological identities of the individual species, DS-PGI and DS-PGII, were examined by enzyme-linked immunosorbent assay using polyclonal antiserum to cartilage-specific proteoglycan monomer from bovine articular cartilage and polyclonal and monoclonal antibodies to DS-PGII. The polyclonal antiserum to cartilage-specific proteoglycan monomer did not react with DS-PGI or DS-PGII, indicating that DS-PGI and DS-PGII possess different core proteins from cartilage-specific proteoglycan monomer. Polyclonal and monoclonal antibodies raised against the mixture of DS-PGI and DS-PGII reacted strongly with DS-PGII, but weakly or not at all with DS-PGI. These results suggest that DS-PGI and DS-PGII possess different core proteins and may represent two different species of dermatan sulfate proteoglycans.

Animals↗
PubMed1984

Can a calcaneal morphologic index determine the degree of osteoporosis?

The proposal that a scoring system of the radiographic trabecular patterns of the os calcis could be related to degree of osteoporosis was tested. The technique fails as it showed no correlation with actual bone density determined by a Compton scatter technique and because of a low level of observer concordance. Possible reasons for the poor performance of the index developed in India when applied to North Americans are discussed.

Age Factors↗
PubMed1983

[Endocarditis parietalis fibroplastica Löffler].

Report on an endocarditis parietalis fibroplastica Löffler in a 54-year-old male. Discussion of the localisation, pathologico-morphologic findings as well as of the differential diagnosis and the therapy. Particular reference to the ten-year course of the disease, which possibly is the success of the treatment.

Endocardial Fibroelastosis↗
PubMed1983

A prospective random study of a single agent versus combination antibiotics as therapy in penetrating injuries of the abdomen.

One hundred patients undergoing operation for penetrating and potentially contaminated wounds of the abdomen were given cefamandole or a combination of cephalothin-tobramycin by a random, single blind method as preventive therapy. Results were evaluable for 49 patients receiving cefamandole for a success rate of 93.9 per cent. The 45 evaluable results in the second group had a success rate of 88.9 per cent. Those in the single therapy group also required fewer days of treatment and of hospital confinement, resulting in lower per patient cost. Results of this study show cefamandole to be an efficacious alternative for surgeons seeking a single agent therapy.

Abdominal Injuries↗
PubMedDate not supplied

Absorption, distribution, metabolism and excretion of the cholecystokinin-1 antagonist dexloxiglumide in the rat.

Single oral doses of 14C-dexloxiglumide were rapidly and extensively absorbed in rats, and eliminated more slowly by females than by males. The respective half-lives were about 4.9 and 2.1 h. Following single intravenous doses, dexloxiglumide was characterised as a drug having a low clearance (6.01 and about 1.96 ml/min/kg in males and females respectively), a moderate volume of distribution (Vss, 0.98 and about 1.1 L/kg in males and females respectively) and a high systemic availability. It was extensively bound to plasma proteins (97%). Dexloxiglumide is mainly cleared by the liver. Its renal clearance was minor. In only the liver and gastrointestinal tract, were concentrations of 14C generally greater than those in plasma. Peak 14C concentrations generally occurred at 1-2 h in males and at 2-4 h in females. Tissue 14C concentrations then declined by severalfold during 24 h although still present in most tissues at 24 h but only in a few tissues (such as the liver and gastrointestinal tract) at 168 h. Decline of 14C was less rapid in the tissues of females than in those of males. Single intravenous or oral doses were mainly excreted in the faeces (87-92%), mostly during 24 h and more slowly from females than from males. Urines contained less than 11% dose. Mean recoveries during 7 days when 14C was not detectable in the carcass except in one female rat ranged between 93-101%. Biliary excretion of 14C was prominent (84-91% dose during 24 h) in the disposition of 14C which was also subjected to facile enterohepatic circulation (74% dose). Metabolite profiles in plasma and selected tissues differed. In the former, unchanged dexloxiglumide was the major component whereas in the latter, a polar component was dominant. Urine, bile and faeces contained several 14C-components amongst which unchanged dexloxiglumide was the most important (eg. up to 63% dose in bile). LC-MS/MS showed that dexloxiglumide was metabolised mainly by hydroxylation in the N-(3-methoxypropyl)pentyl sidechain and by O-demethylation followed by subsequent oxidation of the resulting alcohol to a carboxylic acid.

Absorption↗
PubMedDate not supplied

Absorption, distribution, metabolism and excretion of the cholecystokinin-1 antagonist dexloxiglumide in the dog.

Single oral doses of 14C-dexloxiglumide were rapidly and extensively absorbed in dogs and also eliminated rapidly with a short half-life. Following single intravenous doses, dexloxiglumide was characterised as a drug having a high clearance (30.7 and 27.0 ml/min/kg in males and females respectively), a low volume of distribution (Vss, 0.34 and 0.27 L/kg in males and females respectively) and a moderate systemic availability (about 33%). It was extensively bound to plasma proteins (89%). Dexloxiglumide is mainly cleared by the liver. Its renal clearance was minor. In only the kidney, liver and gastrointestinal tract, were concentrations of 14C generally greater than those in plasma. 14C concentrations generally peaked at 0.25h and declined rapidly during 24h being present only in a few tissues (such as the kidney, liver and gastrointestinal tract) at 24h. Single intravenous or oral doses were mainly excreted in the faeces (77-89%), mostly during 24h. Urine contained up to 7.5% dose. Mean recoveries during 7 days ranged between 93-97%. Biliary excretion of 14C was prominent (64% dose during 24h) in the disposition of 14C which was probably also subjected to some limited enterohepatic circulation. Unchanged dexloxiglumide was the major component in plasma. Urine and faeces contained several 14C-components amongst which unchanged dexloxiglumide was the most important (eg. about 55% dose in faeces). LC-MS/MS of urine and bile extracts showed that dexloxiglumide was metabolised mainly by O-demethylation and by conjugation with glucuronic acid.

Absorption↗