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T Kelly

Publications and source records attributed to T Kelly.

At least 91 records · Page 5Linked to original sources
PubMed1990

Protein-acetaldehyde adducts in serum of alcoholic patients.

Enzyme-linked immunosorbent assay (ELISA) was used to detect the presence of protein-acetaldehyde adducts (-AAs) in human serum samples. Two methods were compared: (1) direct ELISA: samples, rabbit anti-hemocyanin-AA IgG, and beta-galactosidase (beta-gal) conjugated goat anti-rabbit serum IgG added to a 96-well ELISA plate in a stepwise manner; and (2) two-site or sandwich ELISA: serum samples added to an ELISA plate that had been precoated with anti-hemocyanin-AA IgG (the capture antibody) and incubated stepwise with biotinated anti-hemocyanin-AA IgG (the signal antibody) and avidin-beta-gal conjugates. Serum protein-AA levels were then assayed by bound beta-gal activities at OD405. When human hemoglobin (Hgb)-AA was used as a model protein-AA for the sandwich ELISA, the EC50 (estimated concentration that corresponds to 50% of the OD405 response range) was 7 ng/ml. Direct ELISA was less sensitive (EC50 of 120 ng/ml). Adding control human serum to Hgb-AA increased the EC50 of the direct ELISA more than the sandwich ELISA. Intra- and interassay coefficients of variance for sandwich ELISA were both about 8%. Detection of Hgb-AA by sandwich ELISA was highly specific. The above results with anti-hemocyanin-AA IgG were also obtained when anti-myoglobin-AA IgG was used in sandwich ELISA. Using sandwich ELISA and anti-hemocyanin-AA IgG, OD405 for sera of control subjects and alcoholic patients were 0.036 +/- 0.033 (+/- SEM, n = 28) and 0.150 +/- 0.088 (n = 28), respectively. Serum protein-AAs reacted more strongly with anti-myoglobin-AA IgG than anti-hemocyanin-AA IgG.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaldehyde↗
PubMed1990

Accuracy and reproducibility of the MicroScan rapid anaerobe identification system with an automated reader.

Rapid anaerobe identification (MicroScan) panels (4 h) were evaluated both visually and by the AutoScan-4, a computer-controlled microplate reader. The results of both reading methods were compared with identifications obtained by the conventional (Virginia Polytechnic Institute) method. In total, 237 anaerobes were tested. Correct identifications were obtained for 166 strains (70%) by visual reading and 157 strains (66.2%) by the AutoScan-4. Supplementary tests resulted in 80.1 and 76.7% total correct identifications, respectively. Comparison of the two reading methods revealed complete agreement for 169 strains. Differences between the two reading methods were due to difficulties in reading specific reactions. This was especially true with the clostridial species. The performance of the MicroScan system in the identification of anaerobic bacteria appears comparable to that of other 4-h identification systems for anaerobes, but this system shows significant variance from the conventional system. Improvements in the trays and data base are required before the system can be recommended for routine use.

Autoanalysis↗
PubMed1989

Comparison of radio-frequency and electrolytic lesions of the paraventricular hypothalamic nucleus.

Radio-frequency and anodal electrolytic lesions of the paraventricular nucleus (PVN) were found to produce equal and dramatic increases in body weight in female rats. Neither of the groups with lesions had significantly elevated plasma insulin levels during a period of food restriction, but individual values varied greatly. Both groups displayed marked basal hyperinsulinemia after 30 days of food ad lib. It is concluded that radio-frequency and electrolytic PVN lesions produce similar obesity syndromes.

Animals↗
PubMed1989

Dynamic cytoskeleton-integrin associations induced by cell binding to immobilized fibronectin.

We have examined the early events of cellular attachment and spreading (10-30 min) by allowing chick embryonic fibroblasts transformed by Rous sarcoma virus to interact with fibronectin immobilized on matrix beads. The binding activity of cells to fibronectin beads was sensitive to both the mAb JG22E and the GRGDS peptide, which inhibit the interaction between integrin and fibronectin. The precise distribution of cytoskeleton components and integrin was determined by immunocytochemistry of frozen thin sections. In suspended cells, the distribution of talin was diffuse in the cytoplasm and integrin was localized at the cell surface. Within 10 min after binding of cells and fibronectin beads at 22 degrees C or 37 degrees C, integrin and talin aggregated at the membrane adjacent to the site of bead attachment. In addition, an internal pool of integrin-positive vesicles accumulated. The mAb ES238 directed against the extracellular domain of the avian beta 1 integrin subunit, when coupled to beads, also induced the aggregation of talin at the membrane, whereas ES186 directed against the intracellular domain of the beta 1 integrin subunit did not. Cells attached and spread on Con A beads, but neither integrin nor talin aggregated at the membrane. After 30 min, when many of the cells were at a more advanced stage of spreading around beads or phagocytosing beads, alpha-actinin and actin, but not vinculin, form distinctive aggregates at sites along membranes associated with either fibronectin or Con A beads. Normal cells also rapidly formed aggregates of integrin and talin after binding to immobilized fibronectin in a manner that was similar to the transformed cells, suggesting that the aggregation process is not dependent upon activity of the pp60v-src tyrosine kinase. Thus, the binding of cells to immobilized fibronectin caused integrin-talin coaggregation at the sites of membrane-ECM contact, which can initiate the cytoskeletal events necessary for cell adhesion and spreading.

Animals↗
PubMed1988

Purification and characterization of replication protein A, a cellular protein required for in vitro replication of simian virus 40 DNA.

The replication of simian virus 40 (SV40) DNA is largely dependent upon cellular replication proteins. To define these proteins we have made use of a cell-free system that is capable of replicating plasmid DNA molecules containing the SV40 origin of replication. Systematic fractionation-reconstitution experiments indicate that there are a minimum of six cellular proteins that are required for efficient viral DNA replication in vitro. We report here the purification of one of these proteins, replication protein A (RP-A), to homogeneity. RP-A is a multisubunit protein that contains four tightly associated polypeptides of 70, 53, 32, and 14 kDa. Partial proteolysis experiments indicate that the 53-kDa polypeptide is closely related to the 70-kDa polypeptide, suggesting that it may be a proteolytic fragment of the larger subunit. RP-A is absolutely required for reconstitution of SV40 DNA replication in vitro. The purified protein binds to single-stranded DNA and is required for the large tumor (T)-antigen-mediated unwinding of DNA molecules containing the SV40 origin of DNA replication. These properties are consistent with the possibility that RP-A plays a central role in the generation of a single-stranded region at the origin prior to initiation of DNA synthesis. The protein may also function to facilitate unwinding of the parental DNA strands during the elongation phase of SV40 DNA replication.

Antigens, Viral, Tumor↗
PubMed1988

Time of exposure and risk of HIV infection in homosexual partners of men with AIDS.

We interviewed, and tested for HIV antibody, 117 homosexual men who had been regular sexual partners of men who developed acquired immunodeficiency syndrome (AIDS); 85 tested seropositive. Receptive anal intercourse with the index AIDS case and number of different sexual partners with whom subjects were anally receptive were both risk factors. Controlling for the number of partners with whom subjects were anally receptive, we found that the odds ratio of receptive anal intercourse with the case was infinite (95% confidence intervals, 3.3-infinity) if sexual contact continued up to or beyond the time of diagnosis, while the odds ratio was 1.0 (95% CI 0.3-3.2) if contact ceased before the case's AIDS diagnosis. Risk was not associated with the duration or frequency of contact. Our data suggest that the potential for sexual transmission from an HIV-infected person may be greater close to or after the onset of disease.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Upper gastrointestinal endoscopy after cardiac transplantation.

Three hundred four patients have undergone cardiac transplantation at the University of Pittsburgh since 1980. Twenty patients have required 27 upper gastrointestinal (GI) endoscopic procedures. After heart transplantation the primary indications for endoscopy were epigastric pain (six patients with gastritis, one with multiple shallow gastric ulcers, and one with normal test results), mild upper GI bleeding (four patients with esophagitis, two with gastritis, and two with multiple shallow gastric ulcers), dysphagia and odynophagia (two patients with esophagitis), persistent nausea and vomiting (one with normal test results), lower GI bleeding (one with normal test results), and routine follow-up (one with normal test results). After heart-lung transplantation the primary indications for the endoscopy were massive upper GI bleeding (three patients with actively bleeding duodenal ulcers), dysphagia and odynophagia (one patient with esophagitis), mild upper GI bleeding (one patient with gastritis), and routine follow-up (one patient with normal test results). No complications resulted from endoscopy. The procedures were performed in the GI suite without cardiac monitoring. Prophylactic antibiotics were not routinely administered. No patient had a fungal infection of the upper GI tract--a finding attributed to the prophylactic use of nystatin in all patients. Opportunistic viral infections were identified histologically in six patients, including two patients with actively bleeding duodenal ulcers. The possibility of opportunistic viral infections in this immunosuppressed group required aggressive diagnostic techniques, including endoscopy and biopsy, which can be safely performed after cardiac transplantation.

Adult↗
PubMed1987

Purification of two smooth muscle glycoproteins related to integrin. Distribution in cultured chicken embryo fibroblasts.

We have purified two membrane glycoproteins from chicken gizzard smooth muscle. In the presence of reducing agents, these proteins have molecular weights on sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 165,000 and 130,000, but they migrate at 165,000 and 110,000 without reduction. The two proteins can also be isolated as a complex in buffers containing physiologic salt concentrations. This complex has physical properties similar to two proteins of the integrin family of receptors for extracellular matrix proteins, the cell substratum attachment antigen from chicken embryos, and the glycoprotein IIb IIIa complex from mammalian platelets. When the smooth muscle complex is visualized by electron microscopy, it has a striking resemblance to both avian integrin and the glycoprotein IIb IIIa complex. Smooth muscle is a good source of the 165,000 and 130,000 proteins, and purification of both the individual subunits and the complex is achieved using conventional biochemical techniques. Antibodies directed against the 130,000 protein cross-react with integrin but do not cross-react with the 165,000 protein. Immunofluorescence microscopy using these antibodies reveals staining of fibroblast focal contacts and fibrillar streaks which coalign with fibronectin. Whereas monoclonal antibodies against integrin label the periphery of the focal contact more intensely than the center, the anti-130,000-protein serum stains the entire focal contact. Antibodies directed against the 165,000 protein also stain focal contacts and fibrillar streaks of fibroblasts in tissue culture. On the basis of similar physical properties, biochemical characteristics, and immunological cross-reactivity we conclude that the 165,000/130,000 complex is a smooth muscle integrin.

Animals↗
PubMed1987

Comparison of RapID-ANA and Minitek with a conventional method for biochemical identification of anaerobes.

Two micromethods for the identification of anaerobes, one requiring growth (Minitek) and one nongrowth dependent (RapID-ANA), were compared with a conventional identification culture system. For 222 clinical isolates, RapID-ANA agreed with PRAS in 187 (84%) and Minitek agreed for only 170 strains (76%). Both systems identified common isolates well, but encountered some difficulty in identifying less common clostridia and Gram-negative bacilli. Although adequate for most strains, the results from both systems should be interpreted with caution, particularly for less frequently isolated species.

Bacteria, Anaerobic↗
PubMed1987

The role of the community psychiatric nurse in improving treatment compliance in alcoholics.

Patient compliance in alcoholism treatment remains an under-researched topic. Some factors as to why patients comply to treatment have been studied but the intervention of nursing staff who work in the community has not been extensively researched. This study looks at the effect, if any, of having community psychiatric nurses following up a randomly-selected group of new patients referred to the Withington Hospital Alcoholism Treatment Unit. This study looks at the involvement of community psychiatric nurses in their initial treatment.

Alcoholism↗
PubMed1987

Adhesion plaques: sites of transmembrane interaction between the extracellular matrix and the actin cytoskeleton.

In this paper we review what is known about the organization of adhesion plaques, the regions where cells in culture adhere most tightly to the underlying substratum. These specialized areas of the plasma membrane serve as attachment sites for stress fibres. A major objective has been to determine how microfilament bundles are anchored at such regions. In their morphology and composition adhesion plaques resemble the adhesions fibroblasts make to the extracellular matrix. Some extracellular matrix components have been identified on the outside face of adhesion plaques. Within the plasma membrane of adhesion plaques, extracellular matrix receptors, such as the fibronectin receptor (integrin), have been identified. This transmembrane glycoprotein complex has been shown to bind the cytoplasmic protein talin, which, in turn, associates with vinculin. These proteins establish a transmembrane chain of attachment between the extracellular matrix and the cytoskeleton, although how the actin filaments interact with these components remains to be determined. Besides having a structural function, adhesion plaques may also be regions where regulatory signals are transmitted across the membrane. Consistent with this idea has been the finding that various tyrosine kinases and a calcium-dependent protease are concentrated at the cytoplasmic aspect of adhesion plaques. Furthermore, several adhesion plaque proteins become phosphorylated during cell transformation by Rous sarcoma virus. In future work it will be important to determine how such modifications affect the interactions of these proteins and the stability of adhesion plaques.

Actins↗
PubMed1986

Functional organization of the simian virus 40 origin of DNA replication.

To define the sequence elements involved in initiation of DNA synthesis at the simian virus 40 origin of replication, we determined the relative replication efficiencies in vitro and in vivo of templates containing a variety of mutations within the origin region. Replication of the mutants in vitro was assayed by the cell-free DNA replication system that we recently described (J.J. Li and T.J. Kelly, Proc. Natl. Acad. Sci. USA 81:6973-6977, 1984; J.J. Li and T.J. Kelly, Mol. Cell. Biol. 5:1238-1246, 1985), and replication in vivo was assayed after transfection of the mutant templates into COS-1 cells. The minimal origin of replication defined by both assays included a 15-base-pair (bp) imperfect inverted repeat, a 27-bp perfect inverted repeat, and a 17-bp A/T-rich region. T-antigen binding site I was not required for DNA replication, but its presence increased replication efficiency severalfold both in vitro and in vivo. Although SP1 binding sites and enhancers had little or no effect on replication in vitro, the presence of either element markedly increased replication in vivo. Thus, the biological role of these elements is not restricted to stimulating transcription but may be more general.

Antigens, Polyomavirus Transforming↗