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S McConnell

Publications and source records attributed to S McConnell.

At least 73 records · Page 4Linked to original sources
PubMed1980

Simian virus nomenclature, 1980.

Approximately 75 simian viruses, counterparts of other animal viruses, are recognized. Nomenclature of these isolates, in general, consists of an SV (simian virus) or SA (simian agent) numerical series with no attempt to group them according to virus families. The biologic characteristics of these viruses indicate they may be classified into recognized families and groups. A simple sequential numerical designation is recommended as a nomenclature within virus families and groups. Finalization of nomenclature would follow approval by the Study Groups of the International Committee on Taxonomy of Viruses.

Adenoviruses, Simian↗
PubMed1978

Tumor localizing agents: the transport of meso-tetra(p-sulfophenyl) porphine by Vero and HEp-2 cells in vitro.

The mechanism of transport of the tumor localizing agent, meso-tetra(p-sulfophenyl)porphine (TPPS4), was investigated in Vero and HEp-2 cells in vitro. Vero cells proved to be basically impermeable to the porphyrin, but a slow transport was observed. The uptake was linear with time and appeared to be carrier mediated, as it was strongly inhibited by cyanide or low temperature and demonstrated saturation kinetics. Transport in HEp-2 cells was more rapid and non-linear, reaching a plateau after about 2 h. Analysis of this uptake over a 20-fold range of porphyrin concentration revealed it to be biphasic. A low affinity, high capacity component appeared to be unsaturable and was unaffected by low temperature or metabolic inhibitors. This system is probably one of a passive diffusion. The high affinity, low capacity phase is probably carrier mediated. The tumor cells appear to be "leaky" to the porphyrin, with respect to the Vero cells. This may explain part of the localizing ability of TPPS4.

Animals↗
PubMed1978

Intracellular localization of meso-Tetra(p-sulfophenyl)porphine: a potential tumor localizing agent.

The mechanism of meso-tetra (p-sulfophenyl)porphine (TPPS4) localization was examined in Vero and HEp-2 cells in vitro. TPPS4 was found to be relatively nontoxic to both cell types at concentrations up to 200 microgram/ml. However, changes in cellular ultrastructure were observed by electron microscopy, consisting mainly of an increase in membrane-bound vacuoles. The nature of the new structures has not been determined. Both fluorescence microscopy and cellular fractionation indicate that TPPS4 is localized inside the cells studied. Considerable differences in the pattern of localization between the two cell types were found. The TPPS4 in the Vero cells was found to be mainly in the soluble fraction and the red fluorescence was found to be diffuse throughout the cytoplasm. The HEp-2 cells showed TPPS4 fluorescence associated with various cell organelles, predominatly the nucleolus. [14C]-TPPS4 was found in many cellular components but predominantly it was in the soluble and protein fractions. These differences may be significant in the understanding of in vivo localization of this porphyrin in neoplastic tissue.

Animals↗
PubMed1977

Localization of meso-tetra(p-sulfophenyl)porphine in murine sarcoma virus-induced tumor-bearing mice.

meso-Tetra(p-sulfophenyl)porphine (TPPS4) has been found to accumulate in the tumors of mice bearing a murine sarcoma virus-induced rhabdomyosarcoma to a greater degree than in all other tissues except for the kidney. Tumor to tissue ratios of from 3:1 (tumor to liver) to 9:1 (tumor to muscle) were observed. The uptake of TPPS4 was found to be dose dependent, and the highest tumor to tissue ratios were found 96 hours after injection. The water-soluble TPPS4 appears to be cleared through the kidneys and absolute concentrations there are reduced with increasing time after injection. These data are compared with previous studies on TPPS4 localization in Walker 256 carcinosarcoma-bearing mice. In view of this localizing ability and its relative lack of toxicity, TPPS4 seems to represent an ideal candidate for a tumor-localizing agent if high levels of the porphyrin in the kidneys can be reversed.

Animals↗
PubMed1977

Demonstration of equine infectious anemia virus in primary leukocyte cultures by electron microscopy.

Electron microscopy was used to demonstrate the presence of viral particles in primary cultures of leukocytes taken from a horse after SC inoculation with the Wyoming strain of equine infectious anemia virus. Unlike previous studies, the exposure virus was not passaged through cell culture prior to horse inoculation. Cultures were begun approximately 1 week before and 1 week after the 1st pyrexic period after inoculation. In both samples, viral particles and cytoplasmic alterations were observed resembling those previously reported in equine infectious anemia virus and other retravirus-infected cells.

Animals↗
PubMedDate not supplied

An immunohistochemical study of the distribution of biotin in tissues of pigs and chickens.

An optimised indirect peroxidase-anti-peroxidase immunohistochemical technique was used to detect endogenous biotin in frozen tissue sections from biotin-supplemented and biotin-depleted pigs and chickens. A monoclonal anti-biotin antibody was used as primary antibody in this technique. Immunoreactive biotin was detected in many tissues of both species including liver, kidney, pancreas, adipose tissue, adrenal gland, testis, brain, choroid plexus, cardiac and skeletal muscle, epithelium of the respiratory and digestive systems, skin and lymphoid tissues. The specificity of immunostaining for biotin was confirmed by the finding of reduced staining intensities in tissues of biotin-depleted animals compared to those of biotin-supplemented animals. The results of this study suggest that biotin has metabolic functions in a wider range of tissues than previously known. They also indicate that endogenous tissue biotin should be considered as a source of false-positive staining when immunohistochemical or histochemical techniques which use avidin or streptavidin reagents or anti-biotin antibodies as components of the detection system, are applied to tissue sections.

Animals↗