PubMed Health⌕ Search

Biomedical subjects

S Patton

Publications and source records attributed to S Patton.

At least 19 recordsLinked to original sources
PubMed1997

Prosaposin, a neurotrophic factor: presence and properties in milk.

The presence of prosaposin, the precursor of the sphingolipid activator proteins (saposins A, B, C, and D), was investigated in bovine milk. The milk proteins were resolved by SDS-PAGE, blotted onto nitrocellulose sheets, and immunostained. Each of three appropriate antibodies defined a band from milk that matched in mobility the reference prosaposin from human milk at a relative molecular mass of 66,000. Evidence of mature saposins was not found. Prosaposin was detected in milk of other species chimpanzee, rhesus, goat, and rat) and was consistently observed in samples of retail milk and from individual cows. Prosaposin was not associated with particulate matter (fat globules, casein micelles, membrane fragments, and somatic cells) in either human or bovine milk. Rather, prosaposin was located exclusively in the milk serum (whey), existing in monomeric form, as revealed by nondenaturing PAGE. A commercial whey protein concentrate (75% protein) appeared to retain milk prosaposin quantitatively. Properties that were useful in the isolation of prosaposin from milk were its binding to concanavalin A, retention by anion-exchange cellulose, and resistance to precipitation by heating. The possibility that bovine milk prosaposin nutritionally benefits the humans who consume it is enhanced by the fact that only part of its saposin C segment is required for neurotrophic activity.

Animals↗
PubMed1996

Cloning and characterization of the gene encoding 1-cyclohexenylcarbonyl coenzyme A reductase from Streptomyces collinus.

We report the cloning of the gene encoding the 1-cyclohexenylcarbonyl coenzyme A reductase (ChcA) of Streptomyces collinus, an enzyme putatively involved in the final reduction step in the formation of the cyclohexyl moiety of ansatrienin from shikimic acid. The cloned gene, with a proposed designation of chcA, encodes an 843-bp open reading frame which predicts a primary translation product of 280 amino acids and a calculated molecular mass of 29.7 kDa. Highly significant sequence similiarity extending along almost the entire length of the protein was observed with members of the short-chain alcohol dehydrogenase superfamily. The S. collinus chcA gene was overexpressed in Escherichia coli by using a bacteriophage T7 transient expression system, and a protein with a specific ChcA activity was detected. The E. coli-produced ChcA protein was purified and shown to have similar steady-state kinetics and electrophoretic mobility on sodium dodecyl sulfate-polyacrylamide gels as the enoyl-coenzyme A reductase protein prepared from S. collinus. The enzyme demonstrated the ability to catalyze, in vitro, three of the reductive steps involved in the formation of cyclohexanecarboxylic acid. An S. collinus chcA mutant, constructed by deletion of a genomic region comprising the 5' end of chcA, lost the ChcA activity and the ability to synthesize either cyclohexanecarboxylic acid or ansatrienin. These results suggest that chcA encodes the ChcA that is involved in catalyzing multiple reductive steps in the pathway that provides the cyclohexanecarboxylic acid from shikimic acid.

Amino Acid Sequence↗
PubMed1995

The epithelial mucin, MUC1, of milk, mammary gland and other tissues.

MUC1 is a mucin-type glycoprotein that is integrally disposed in the apical plasma membrane of the lactating epithelial cell and protrudes from the cell surface into the alveolar lumen where milk is stored. Envelopment of milk fat globules by this membrane accomplishes their secretion and conveys MUC1 into milk. The human form of this mucin has been detected in many other organs, tissues and body fluids. It projects from the cell surface as long filaments. In the human and a number of other species, MUC1 is polymorphic due to variable numbers of a tandemly repeated segment 20 amino acids in length. The individual codominantly expresses two alleles for the mucin so that differences in its size among individuals and between the two forms of an individual are observed. The tandem repeats are rich in serines and threonines which serve as O-glycosylation sites. Carbohydrate content of MUC1, as isolated from milk of human, bovine and guinea pig, is approximately 50%. The oligosaccharides carry substantial sialic acid at their termini and this accounts for two putative functions of this mucin, i.e., to keep ducts and lumens open by creating a strong negative charge on the surface of epithelial cells which would repel opposite sides of a vessel, and to bind certain pathogenic microorganisms. MUC1 is protease resistant (trypsin, chymotrypsin and pepsin) and large fragments of it can be found in the feces of some but not all breast-fed infants. MUC1 has a highly varied structure because of its polymorphism, qualitative and quantitative variations in its glycosylation between tissues, individuals and species, and differences due to divergence in the nucleotide sequences among species. Sequencing of the MUC1 gene for various species is showing promise of revealing unique evolutionary relationships and has already indicated conserved aspects of the molecule that may be functionally important. Among these are positions of serine, threonine and proline in the tandem repeats and a high degree of homology in the transmembrane and cytoplasmic segments of the molecule.

Amino Acid Sequence↗
PubMed1995

Direct measurement of nitric oxide in human beings.

Nitric oxide is a short-lived radical involved in various biological processes. We have used an electrochemical microsensor to detect nitric oxide signals in blood vessels of healthy volunteers. The sensor was inserted into a hand vein, and the vessel was stimulated with acetylcholine or bradykinin. Dose-dependent signals were detected and were attenuated by an inhibitor of nitric oxide synthase. The results provide further evidence that endothelium-derived relaxing factor is nitric oxide and demonstrate a method for monitoring the L-arginine/nitric-oxide pathway in human beings.

Acetylcholine↗
PubMed1995

Comparison of the efficacies of three heartworm preventives against experimentally induced infections with Ancylostoma caninum and Toxocara canis in pups.

Forty 11- to 12-week-old helminth-naive Beagles were categorized by sex and weight and randomly assigned to 4 treatment groups (group 1, ivermectin/pyrantel pamoate; group 2, milbemycin oxime; group 3, untreated control; group 4, diethylcarbamazine/oxibendazole). Each pup was inoculated PO with approximately 100 infective Ancylostoma caninum larvae and 100 larvated Toxocara canis eggs on day 0, and repeatedly at 7-day intervals thereafter until day 56. Administration of anthelmintics also began on day 0, and subsequent treatments were administered according to label recommendations at 30-day intervals (groups 1 and 2) or daily (group 4) for a period of 90 consecutive days. Body weight and A caninum and T canis fecal egg counts were measured at weekly intervals, and clinical observations of health status were conducted twice daily. Pups were euthanatized on day 90, and total gastrointestinal worm burdens were determined. Compared with mean A caninum egg counts of group-3 control pups, egg counts in group-1 pups were significantly (P < or = 0.0001) lower on every sampling days 35, 42, 49, 63, 70, 77, and 84, and were consistently the highest of all treated groups, and egg counts of group-4 pups were significantly (P < or = 0.0001) lower on every sampling date from day 14 to day 90, and were consistently the lowest of all treated groups. Compared with mean A caninum egg counts of group-3 pups, egg counts in group-1 and group-2 pups were lower by 97.8 and 90.8%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1995

Risk factors associated with transmission of Toxoplasma gondii to sows kept in different management systems in Tennessee.

Of 3841 serum samples from sows received from the Tennessee State Diagnostic Laboratory in 1991-1992, 1130 were positive for Toxoplasma gondii antibody. The total number of farms sampled was 343. The observed seroprevalence was 36% for both years. A questionnaire that dealt with herd management practices was mailed to 303 of the swine farms that were sampled; 107 (35%) responses were returned and analyzed. There was no significant difference in the seroprevalence of T. gondii in the sows on the farms of respondents and non-respondents. From the analysis of the questionnaire, sows associated with cats were 2.6 times more likely to be seropositive for T. gondii than sows that were not associated with cats. Sows kept outdoors at any time were 23 times more likely to be seropositive than sows that were kept indoors. Sows on small farms (< 29 sows) were 4.5 times more likely to be seropositive than sows on large farms (> 29 sows).

Animal Husbandry↗
PubMed1995

Polymorphic forms of the epithelial mucin, PAS-I (MUC1), in milk of Holstein cows (Bos taurus).

The polymorphic epithelial mucin, PAS-I (also known as MUC1), in individual milk samples from 119 Holstein cows was resolved into bands on SDS-gels. Mobility indices established for these bands provided evidence of four and possibly five polymorphic forms. Sialic acid, a major component of the oligosaccharide portion of PAS-I, was removed from the mucin by treatment of milk samples with neurominidase. This reduced the mobility of the mucin bands but did not alter their mobility relationships within a sample or among samples. Consideration of evidence from this and other studies indicates that the four or five polymorphic forms correspond to alleles, which are inherited, one each from sire and dam, and co-dominantly expressed. It appears that the Holstein population may carry several more alleles for PAS-I than do Ayrshire, Jersey or Brown Swiss cattle. In addition to these breed differences, some remarkable molecular differences have been noted between MUC1 (PAS-I) of human and mouse suggesting that research regarding molecular evolution of this mucin could provide another approach to understanding relationships among species.

Animals↗
PubMed1995

Associations of the epithelial mucin, PAS-1, with yield, health, and reproductive traits in Holstein dairy cows.

Five polymorphic forms of the epithelial mucin, PAS-1, were identified in milk by SDS-PAGE. The sizes of PAS-1 ranged from 194.5 to 163 kDa. Mature equivalent milk, fat, and protein yields and protein and fat percentages from 139 cows in The Pennsylvania State University herd were analyzed with two models. Both models contained a year and season combination of calving and parent average. In Model [1], yields were regressed on the mean size of PAS-1 either linearly or linearly and quadratically. Model [2] included PAS-2 phenotype as a discrete variable. Lactation mean of somatic cell scores (119 cows), number of times bred (136 cows), and days open (136 cows) were analyzed with the same two models excluding parent average (data not available). Mean size of PAS-1 was not linearly related to the traits evaluated. The effects of PAS-1 phenotypes as a discrete variable were significant for mature equivalent fat and protein yields, fat percentage, number of times bred, number of times bred restricted to 3, and days open restricted to 150 d. Overall, there was little indication of an important linear or quadratic relationship between PAS-1 size and traits measured.

Animals↗
PubMed1995

Empowering women: improving a community's health.

Community Health Aides (volunteers) were trained to become health resource persons in their own community. The curriculum for the training sessions was modeled after the Camp Health Aide Program, which is based on the belief that with information and support, migrant farmworkers can make changes in their lives and environment to improve their health and the community's health.

Arkansas↗
PubMed1994

Cloning of PBDX, an MIC2-related gene that spans the pseudoautosomal boundary on chromosome Xp.

The pseudoautosomal boundaries are the interface between pseudoautosomal and sex chromosome-specific DNA sequences. We have isolated a gene, PBDX, from the human pseudoautosomal boundary region of Xp. The three exons at the 5' end of PBDX are situated in the pseudoautosomal region immediately downstream of MIC2, whereas the other seven exons are in the X-specific region. Hence, PBDX is inherited in two modes: its 5' end is pseudoautosomally inherited and its 3' end is X-linked. The predicted amino acid sequence of the 540 bp coding region is 48% homologous to 12E7, the product of MIC2. By virtue of its position, PBDX becomes an excellent candidate for the XG blood group gene.

12E7 Antigen↗
PubMed1994

Detection of large fragments of the human milk mucin MUC-1 in feces of breast-fed infants.

Evidence is growing that high-molecular-weight glycoproteins (mucins) of human milk bind to certain pathogenic microorganisms and thus could interfere with their colonization of the infant gut. This investigation sought to determine whether one of the two principal milk mucins, MUC-1 (also known as PAS-0 and episialin), persists into the feces. Fecal samples from seven breast-fed and seven formula-fed infants, aged from 20 days to 6 months, were analyzed. Glycoproteins in the specimens, solubilized with sodium dodecylsulfate, mercaptoethanol, and heat, were resolved by gel electrophoresis. The gels were blotted on nitrocellulose sheets that were immunostained with monoclonal antibodies specific for epitopes in the tandem repeat region of MUC-1. Mucin fragments of approximately 200,000 MW were detected in specimens from three of the seven breast-fed subjects; only one of them showed evidence of the intact mucin. Four breast-fed and all seven formula-fed babies were negative for the mucin in their stools. While these results provide evidence of a variable degree of breakdown, we speculate that MUC-1 resists degradation in the gut and thus may help bind host-detrimental microorganisms and inhibit their colonizing and infecting actions.

Animals↗
PubMed1994

Parasites of wild felidae in Thailand: a coprological survey.

Ninety-two fecal samples were collected from leopards (Panthera pardus, n = 54), tigers (P. tigris, n = 19), and leopard cats (Felis bengalensis, n = 3) in Huai Kha Wildlife Sanctuary, Thailand; four samples that may have come from clouded leopards (Neofelis nebulosa) or Asian golden cats (Felis temminicki) were identified as from small to medium cats. Twelve samples were identified as from large cats. Samples preserved in 10% formalin were examined for parasite eggs, larvae, cysts, and oocysts by centrifugal sugar flotation and sedimentation techniques. Ninety-six percent of all samples were positive, including 94% of the leopard, all of the tiger, clouded leopard, golden cat, and leopard cat samples. Diagnostic stages were identified from Paragonimus sp., Echinostomatidae, Dicrocoeliidae, Pseudophyllidea, Taeniidae, Mesocestoides sp., Hymenolepididae, Acanthocephala, Spiruroidea, Gnathostoma sp., Molineus sp., Ancylostomoidea, Mammomonogamus sp., Toxocara sp., Toxascaris sp., Metastrongyloidea, Capillaria spp., Isospora sp., Toxoplasma-like, Sarcocystis spp., and Giardia sp.

Animals↗
PubMed1993

Diffusion of nitric oxide in the aorta wall monitored in situ by porphyrinic microsensors.

Porphyrinic sensors were used for the in situ monitoring of nitric oxide release and diffusion in the endothelial cell, as well as its subsequent diffusion from the endothelial cell through the muscle cells found in the rabbit aorta. The experimental data was compared with that predicted based on Fick's equation for linear diffusion. A time delay of 1.5 s between prediction and experimental concentration of NO due to its chemical reactions was observed at the distance of 100 microns from endothelial cell. About 37% of the NO produced is consumed in chemical reactions in the aorta.

Animals↗
PubMed1993

Pulmonary arterial changes in feline dirofilariasis.

Eleven cats with spontaneous dirofilariasis were necropsied; ten were domestic shorthairs and one was a Persian. The cats ranged in age from 1 to 10 years, and 6/11 cats were male. One to three heartworms were present in the right ventricle and pulmonary arteries of each of the 11 cats. Patchy areas of rugose thickening of the intima of the pulmonary trunk and marked villous endarteritis of lobar and medium-sized pulmonary arteries were observed. Affected larger vessels were partially occluded by large villous intimal proliferations that were lined by hyperplastic endothelial cells supported by connective tissue stroma. Moderate to marked infiltration of eosinophils and mononuclear inflammatory cells was consistently observed in the intima of affected larger pulmonary arteries. Thrombosis of pulmonary arteries was seen in five cats. Medial hypertrophy, mild intimal proliferative changes, and focal infiltrations of leukocytes were seen in small pulmonary arteries. Lesions indicative of right-sided heart failure consisting of right ventricular dilation and chronic passive congestion of the liver were observed in four cats.

Animals↗
PubMed1992

Prevalence of Dirofilaria immitis and Dipetalonema reconditum infection in dogs: 805 cases (1980-1989).

Clinical records of 6,977 dogs examined at the small animal clinic of the University of Tennessee College of Veterinary Medicine from January 1980 through December 1989 were analyzed to determine the prevalence and changing frequency of Dirofilaria immitis and Dipetalonema reconditum infection. Using the Knott's test on these dogs, 805 (11.54%) tested positive for microfilariae, with D immitis in 430 dogs (6.16%), and Dip reconditum in 375 dogs (5.37%). Statistical analysis confirmed that the prevalence of D immitis and that of Dip reconditum were essentially equal in the population of dogs included in this study. There was a slight decrease in the prevalence of D immitis over the 10 years examined, but the prevalence of Dip reconditum remained constant. The results were not affected by year-to-year variability in the number of examinations performed. On the basis of our findings, in eastern Tennessee, those veterinarians who diagnose heartworm infection by the presence of microfilariae without differentiating the species involved, risk misdiagnosing 50% of the cases. If the patterns of prevalence seen in recent years continue, the chances of error may actually increase.

Animals↗