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S Patton

Publications and source records attributed to S Patton.

At least 91 records · Page 5Linked to original sources
PubMed1989

Differences between individuals in high-molecular weight glycoproteins from mammary epithelia of several species.

Milk fat globules are secreted by envelopment in plasma membrane of the lactating cell. SDS-gel electrophoresis of proteins from this membrane has revealed differences between milk donors in two mucin-like glycoproteins. One of these glycoproteins resolves in 3% acrylamide stacking gel and the other in 4% running gel. The proteins vary in number of bands (one or two) and band mobilities. This polymorphism arises, at least in part, from expression of hypervariable genes. In this study, gel electrophoretic evidence of similar polymorphism in glycoproteins from cow, chimpanzee, horse and human milks is presented. In distinction to the other species, the cow expressed only one of these proteins which was detected in the running gel at Mr 180,000 to 200,000. The electrophoresis pattern for this protein from six cows was highly varied with respect to number (one or two) and position of bands. Peanut agglutinin, wheat germ agglutinin and concanavalin A all were bound specifically by bands of the bovine glycoprotein. Binding of concanavalin A distinguishes the bovine protein from the two human glycoproteins. Further studies of species differences should help shed light on the evolution of these unique glycoproteins and their possible functions in mother and young.

Animals↗
PubMed1989

Prehistoric parasitism in Tennessee: evidence from the analysis of desiccated fecal material collected from Big Bone Cave, Van Buren County, Tennessee.

Eight samples of desiccated human feces collected from Big Bone Cave (40VB103), Van Buren County, Tennessee, were analyzed to determine the presence of ecto- and endoparasitic infection among the prehistoric population using the cave. Radiocarbon-dated torch material from the cave indicated that it was a locus of human activity 2,177 +/- 145 yr ago. Parasitic species identified were: Ascaris lumbricoides, Enterobius vermicularis, fleas of the tribe Phalacropsyllini, and protozoan cysts. The cysts were identified as Giardia using an indirect immunofluorescent antibody test. The only report of Giardia in a prehistoric context is the identification of cysts in 2 1,800-yr-old paleofecal specimens from a cave in Israel. This is the first report of Giardia from paleofeces in the New World.

Animals↗
PubMed1988

Incidence and characteristics of cell pieces on human milk fat globules.

For biochemical and nutritional purposes, milk fat globules of a species are assumed to be more or less uniform. The incidence of organelle-containing cytoplasm (crescents) on human milk fat globules was determined by fluorescence microscopy employing acridine orange. The percentage of globules with crescents in 20 predominantly morning samples from 17 donors ranged from 1 to 38% with three-quarters falling between 3 and 8%. However, analysis of morning and night samples from eight donors showed a significant nocturnal rise in the proportion of globules with crescents. Values for night samples were, on average, twice those for morning samples. Crescents deteriorate in human milk. These changes begin in the breast, with marked disintegration occurring in milk during 36-h storage at 2 degrees C. Crescents were isolated from globules by churning and separated from the released membrane by selective centrifugation. SDS-polyacrylamide gel electrophoresis showed that crescents contribute bands which render the globule protein pattern more complex. The significance of crescents in globule secretion, globule membrane preparation, infant nutrition and as a source of mammary cell components is discussed.

Acridine Orange↗
PubMed1988

Structural, histochemical and biochemical observations on horse milk-fat-globule membranes and casein micelles.

Horse milk fat globules (MFGs) and casein micelles were studied using freeze fracturing, freeze etching and thin-section electron microscopy, as well as lectin histochemistry, gel electrophoresis, and Western blotting. Horse MFGs were found to be relatively small, their average volume-surface diameter being about 2.75 microns. The MFG membrane is composed of three layers: an inner proteinaceous coat occasionally having a paracrystalline substructure, a unit membrane, and a prominent filamentous glycocalyx. The last is rich in glycoconjugates, as revealed by its binding of various lectins. In addition, the glycocalyx binds cationized ferritin, which indicates the presence of negative electric charges. Gel electrophoresis revealed the presence of high-molecular-weight glycoproteins in the MFG membrane of horse milk. Such glycoproteins are also present in human MFG membranes but are absent in the bovine MFGs. The casein micelles in horse milk are relatively large, their average volume-surface diameter being about 200 nm.

Animals↗
PubMed1988

Milk fat globules: fatty acid composition, size and in vivo regulation of fat liquidity.

Populations of large and small milk fat globules were isolated and analyzed to determine differences in fatty acid composition. Globule samples were obtained by centrifugation from milks of a herd and of individual animals produced under both pasture and barn feeding. Triacylglycerols of total globule lipids were prepared by thin layer chromatography and analyzed for fatty acid composition by gas chromatography. Using content of the acids in large globules as 100%, small globules contained fewer short-chain acids, -5.9%, less stearic acid, -22.7%, and more oleic acids, +4.6%, mean values for five trials. These differences are consistent with alternative use of short-chain acids or oleic acid converted from stearic acid to maintain liquidity at body temperature of milk fat globules and their precursors, intracellular lipid droplets. Stearyl-CoA desaturase (EC 1.14.99.5), which maintains fluidity of cellular endoplasmic reticulum membrane, is suggested to play a key role in regulating globule fat liquidity. Possible origins of differences between individual globules in fatty acid composition of their triacylglycerols are discussed.

Animals↗
PubMed1988

Glycoprotein filament removal from human milk fat globules by heat treatment.

Freeze-etch electron microscopy was applied to milk fat globules to observe surface details. A remarkable array of filaments, approximately 0.5 micron in length, was seen on human, but not bovine, globules. Heating human globules removed the filaments that were identified as high molecular weight glycoproteins by freeze-etch and gel electrophoretic analysis of the heating medium. Extraction of these globule glycoproteins was slight at 60 degrees C for one minute but substantial and tending to plateau at 80 degrees C for one minute. Such heat-induced alterations of the milk fat globule surface provide an alternative or additional explanation to milk lipase inactivation as the cause of reduced milk fat absorption from heated milk by the preterm infant.

Animals↗
PubMed1987

Achieving therapeutic goals in insulin-using diabetic patients with non-insulin-dependent diabetes mellitus. A weight reduction-exercise-oral agent approach.

Non-insulin-dependent diabetes mellitus (NIDDM) is the most common form of diabetes in the civilized world. Its consequences include microvascular and macrovascular disease, both of which appear to evolve from a common background of obesity and physical inactivity. The current study was undertaken in obese patients with NIDDM to see whether improvements could be made in glycemic control as well as in many cardiovascular risk factors (obesity, hypertension, lipid abnormalities, and physical inactivity) that are typical of this condition. Fifteen obese insulin-using patients with NIDDM (average body mass index, 34.0) were treated with a 500-calorie formula diet for eight to 12 weeks. Administration of insulin and diuretics was discontinued at the onset of the study. A eucaloric diet was begun at eight to 12 weeks and maintained until Week 24. A behaviorally oriented nutrition-exercise program was instituted at the beginning of the study. Glipizide or placebo was added (randomized) at Week 15 if the fasting plasma glucose level in patients exceeded 115 mg/dl. Patients lost an average of 22 pounds over the course of 24 weeks. Frequency and duration of physical activity increased significantly from baseline, as did the maximal oxygen consumption rate. Glycemic control by 15 weeks (without insulin) was similar to baseline (with insulin). With the addition of glipizide at Week 15, both fasting plasma glucose and glucose tolerance improved significantly. This improvement was not observed with placebo. In addition, both systolic and diastolic blood pressure decreased by about 10 mm Hg. There were no significant changes in the levels of serum lipids or glycosylated hemoglobin. In conclusion, a multifaceted intervention program, employing weight reduction, exercise, diet, and glipizide therapy, can be instituted in insulin-using patients with NIDDM, with improvement in glycemic control and in certain risk factors (hypertension, obesity, physical inactivity) for cardiovascular disease.

Adult↗
PubMed1987

Differences between individuals in high-Mr glycoproteins from human mammary epithelia.

SDS-polyacrylamide gel electrophoretic analysis of high molecular mass glycoproteins from human milk fat globules revealed that the pattern of bands is unique for each milk donor. The number, position, width and intensity of bands varied between donors. A difference in the pattern of sisters could be discerned. There is evidence that these mucin-like glycoproteins, which originate from the plasma membrane of the mammary epithelial cell, occur in other cells and tissues. They may function in the immunorecognition system because of their individual-specific character and cell surface location.

Female↗
PubMed1987

Gel electrophoretic analysis of proteins in human milk and colostrum.

Protein patterns of skim milk and fat globule phases were relatively unchanging throughout 9 months lactation, the only notable differences being a rise in lysozyme and a decline up to 6 months with increase thereafter in lactoferrin. Profound changes in protein patterns of the breast secretion were observed during the first week postpartum. True colostrum, in which peptides of sIgA dominate the protein patterns, exists for at most the 2 initial days of secretion. Proteins of mature milk are not coordinated to appear in the colostral secretion simultaneously. A band corresponding to alpha-lactalbumin is present from the initial secretion; that for beta-casein emerges approximately 2 days layer.

Colostrum↗
PubMed1986

A method for isolation of milk fat globules.

The traditional procedure for isolating milk fat globules involves repeated cycles of centrifuging to obtain globules and redispersion of them in fresh buffer to eliminate other milk components. We have evaluated a simpler, less manipulative method whereby globules are centrifuged out of the milk and through an overlying buffer layer. Human milk samples ranging from 0.1 to 35 ml were centrifuged at 1500 X g for 20 min after deposition under a suitable quantity of buffer. This yielded purified globules, in less time, which could be dispersed more satisfactorily than those by the traditional procedure. Protein, phospholipid and cholesterol contents of globules by the two methods were quite similar. A lower protein content (10.4 vs 13.2 mg/g of lipid) was characteristic of globules prepared by the multiple wash method. However, large differences could not be seen in gel electrophoresis patterns of the proteins. By using plastic centrifuge tubes, tube freezing and cleavage just below the globule layer enables clean separation of globule and nonglobule phases for analysis of milk component distributions. Macro (5 to 35 ml of sample) and micro (200 microliter or less) versions of the method are described. Limited trials showed that the method can be applied satisfactorily to cow's and goat's milks, but for highly pure globules a deeper buffer column than that used with human milk is required because of their much higher casein content.

Animals↗
PubMed1986

A coprological survey of parasites of wild neotropical felidae.

In conjunction with an ecological study of jaguars in the Cockscomb Basin of Belize, Central America, fecal samples from jaguars (Panthera onca), jaguarundis (Felis yagouaroundi), ocelots (Felix pardalis), and pumas (Felix concolor) were examined for parasite products (eggs, larvae, and oocysts). Of the 45 samples examined, 39 (86.7%) were positive for parasite products, 23 of 25 (92%) jaguar samples were positive, as were all of the puma (4/4) and ocelot (8/8) samples. Four of 6 samples from unknown species were positive (66.7%). Two jaguarundis samples were negative. The following were identified in the samples: Paragonimus sp. eggs, Taeniidae eggs, Strongylate eggs, Toxocara cati eggs, Toxascaris sp. eggs, Capillaria sp. eggs, Spiruridae eggs, Aelurostrongylus sp. larvae, Oncicola sp. eggs, Hammondia pardalis oocysts, Isospora sp. oocysts, Toxoplasma gondii-like oocysts and Sarcocystis sp. sporocyst.

Animals↗
PubMed1984

Morphometric evaluation of lipid droplet associations with secretory vesicles, mitochondria and other components in the lactating cell.

The size, cellular location, and identity of surface-associated components were determined for lipid droplets in lactating cells. Transmission electron-microscopic measurements were made involving 3801 droplets in approximately 211 cells from three rats and 1197 droplets in 66 cells from a mouse. For the purposes of droplet evaluation, cells were divided into seven locations ranging from basal to secreting positions. Droplets were also categorized with respect to contact with other droplets, basolateral plasma membrane, mitochondria, Golgi apparatus, secretory vesicles, and endoplasmic reticulum-cytoplasm (ERC). Data on droplet size showed that droplet growth occurs mainly in the secretory position, confirming previously published findings. Lipid droplets from mouse tissue, although somewhat smaller in size showed similar growth trends to those of the rat. Data on numbers of droplet contacts and percentages of droplet circumferences involved in associations with other cell components showed that the dominant interaction of lipid droplets was with the ERC. However, intimate association of droplets with mitochondria was noted in all cellular locations. In addition, nursed animals exhibited a greater proportion of droplet surface association with secretory vesicles and less in contact with mitochondria in comparison to those not nursed. The significance of these relationships to milk synthesis and secretion is discussed.

Animals↗
PubMed1984

Internalization of ferritin-concanavalin A by the lactating mammary cell in vivo.

Ferritin-concanavalin A (Fer-Con A) was used to label the apical plasma membrane of the lactating cell to determine whether membrane internalization takes place. Rat glands were infused in vivo via the teat with 0.2 mg of Fer-Con A in 0.2 ml tris buffer (pH 7.0) containing 0.1% trypan blue, the latter acting as a marker of the infusate. Tissues were obtained from separate animals 5, 10 and 60 min postinfusion. Fer-Con A was seen in alveolar lumina bound to the outer surfaces of apical plasma membrane, microvilli and milk fat globules. It was observed within lactating cells on the inner membrane surfaces of endocytotic vesicles, Golgi cisternae, and secretory vesicles containing casein micelles, and in multivesicular bodies and lysosomes. Internalization of the ferritin-lectin conjugate into casein-containing secretory vesicles was detectable in the 5-min postinfusion tissue. Lysosomes were the only structures in control tissue that contained particles bearing some resemblance to Fer-Con A. The data provide evidence that apical plasma membrane is internalized and distributed to a number of intracellular compartments.

Animals↗