Metabolic effects of high-carbohydrate, high-fiber diets for insulin-dependent diabetic individuals.

The metabolic effects of high-carbohydrate (70%), high-fiber (70 g) (HCHF) and low-carbohydrate (39%), low-fiber (10 g) (LCLF) diets were examined for 10 subjects with insulin-dependent diabetes mellitus (IDDM). After a 1-wk control period subjects on a metabolic ward were randomly allocated to HCHF or LCLF diets for 4 wk. After a 6-wk washout period subjects re-entered the metabolic ward for 4 wk on the alternate diet. Artificial-pancreas studies were performed on each diet for measurement of insulin requirements. Compared with the LCLF diet, the HCHF diet reduced basal insulin requirements (P less than 0.025), increased carbohydrate disposed of per unit insulin (P less than 0.0008), and lowered total (P less than 0.0004) and high-density-lipoprotein cholesterol (P less than 0.0013). Glycemic control and other lipid fractions did not differ significantly. These results suggest that in IDDM patients, HCHF diets enhance peripheral glucose disposal, decrease basal insulin requirements, and lower total cholesterol without altering glycemic control or triglycerides.

Serum angiotensin-converting enzyme in leprosy.

Serum angiotensin-converting enzyme activity was measured in 91 adult healthy and lepromatous armadillos before inoculation with M. leprae and at necropsises. Mean ACE values were significantly elevated in armadillos with leprosy and the degree of elevation was roughly proportional to the extent of infection. There was also significant difference in the serum ACE levels between Florida and Louisiana armadillos. The dapsone treatment resulted in bringing these levels to normal. Serial assays of serum, ACE provided information on the response of armadillos to dapsone therapy.

Glycerolipid biosynthesis in rat adipose tissue. Influence of adipocyte size.

A simple one-step filtration method is described to separate larger adipocytes from the smaller ones by using nylon screen (52 microM pore size). Adipocytes retained on the screen were larger (60-90 micrometers) compared with those that passed through the screen. By using this separation technique, activities of various enzymes involved in triacylglycerol formation from sn-glycerol 3-phosphate were measured in the larger and smaller adipocytes isolated from gonadal fat-depots. The homogenates from larger adipocytes were more active in lipid formation compared with those derived from small adipocytes. This was evident from the increased activities of sn-glycerol 3-phosphate acyltransferase. Mg2+-dependent phosphatidate phosphohydrolase and diacylglycerol acyltransferase in the larger adipocytes. The activities of these enzymes were also measured in the adipocytes isolated from gonadal, perirenal and subcutaneous fat-depots. Subcutaneous adipocytes were smaller and were less active in lipid formation than gonadal and perirenal adipocytes. These measurements in the activities of individual enzymes provide evidence that the entire pathway of esterification via sn-glycerol 3-phosphate is accelerated in the larger adipocytes.

Inmunización contra la leptospirosis: continuación de las pruebas realizadas en cricetos con vacunas obtenidas de cepas aisladas en Barbados / Immunization against leptospirosis: continued vaccine trials in hamsters using strains isolated from Barbados

Suspensiones calentadas de células enteras provenientes de cepas copenhageni del serotipo de Leptospira interrogans, aisladas en el campo, en Barbados, demostraron ser inmunógenos protectores contra la leptospirosis experimental (AU)

Immunization against leptospirosis: continued vaccine trials in hamsters using strains isolated from Barbados.

Heated whole-cell suspensions of L. interrogans serotype copenhageni strains isolated from the field in Barbados have proved to be protective immunogens against experimental leptospirosis.

Immunization against leptospirosis: continued vaccine trials in hamsters using strains isolated from Barbados

Heated whole-cell suspensions of L. interrogans serotype copenhageni strains isolated from the field in Barbados have proved to be protective immunogens against experimental leptospirosis (AU)

Inmunización contra la leptospirosis: ensayo de vacuna en cricetos con antígenos de células enteras muertas por calor y de envoltura externa / Immunization against leptospirosis: vaccine trial with heat-killed whole-cell and outer envelope antigens in hamsters

Se evaluó la utilidad, como vacuna, de dos preparaciones antigénicas de leptospiras. Las suspensiones de células enteras sometidas a calentamiento demostraros ser muy eficaces para proteger a los cricetos contra la leptospirosis experimental (AU)

Demonstration of extracellular material at the surface of pathogenic T. pallidum cells.

Pathogenic T. pallidum cells possess and extracellular layer when observed in vivo and in vitro after exposure to ruthenium-red. The extracellular layer is partially removed from a pre-fixed cell by repeated washing in vitro. Non-pathogenic treponemes examined in this study do not possess an extracellular layer. It is hoped that the data presented herein will cause our colleagues to take another look at the methods and techniques used for preparing pathogenic T. pallidum cells for practical end-point objectives.

Experimental syphilis vaccines in rabbits. I. Differential protection with an adjuvant spectrum.

This study shows that 1 per cent. glutaraldehyde fixation of unwashed Treponema pallidum, Nichols pathogen, preserves the integrity of the outer envelope as well as the ruthenium-red (RR) staining extracellular slime layer. Since other researchers wash their treponemal suspensions before preparing their vaccines, it is likely that the vaccine preparations used in this study contain antigens not tested elsewhere. In an attempt to eliminate the requirement of large numbers of injections to achieve any protection, the rabbits in this study were injected with glutaraldehyde-fixed T. pallidum (GFTP) only once, with or without one of a spectrum of adjuvants, and 5 months later were challenged intradermally or intratesticularly with freshly harvested pathogenic treponemes. Data of time of lesion appearance and severity of lesions reveal a differential protective effect of the various vaccine preparations when compared to the response of non-vaccinated controls. Vaccines which included phytohaemagglutinin (PHA) or alumina C gel (ALC) as adjuvants provided some degree of protection, whereas vaccines which contained the adjuvants incomplete Freund's, zymosan, complete Freund's, polyadenylic-polyuridylic acid, or no adjuvant at all produced enhanced infections. The differential protection data indicate that various portions of the immune mechanism are either suppressed or are not stimulated by T. pallidum antigens alone, but can be made to respond with a minimum of vaccine injections.

Immunization against leptospirosis: vaccine trials with heat-killed whole cell and outer envelope antigens in hamsters.

Heat-killed whole cell and outer envelope antigens prepared from homologous virulent and avirulent strains of Leptospira serotypes canicola and pomona were evaluated for protecting hamsters against experimental leptospirosis. The heat-killed bacterins proved at least as effective as the outer envelope antigens, or more so, in providing protection against death and infection, and they are easier and more economical to prepare.

Immunization against leptospirosis: vaccine trials with heat-killed whole cell and outer envelope antigens in hamsters

Heat-killed whole cell and outer envelope antigens prepared from homologous virulent and avirulent strains of Leptospira serotypes canicola and pomona were evaluated for protecting hamsters against experimental leptospirosis. The heat-killed bacterins proved at least as effective as the outer envelope antigens, or more so, in providing protection against death and infection, and they are easier and more economical to prepare (Au)

Immunization against leptospirosis: vaccine trials with heat-killed whole cell and outer envelope antigens in hamsters

Heat-killed whole cell and outer envelope antigens prepared from homologous virulent and avirulent strains of Leptospira serotypes canicola and pomona were evaluated for protecting hamsters against experimental leptospirosis. The heat-killed bacterins proved at least as effective as the outer envelope antigens, or more so, in providing protection against death and infection, and they are easier and more economical to prepare (Au)

Isolation and chemical characterization of outer envelope of Leptospira pomona.

Cells of Leptospira interrogans serotype pomona harvested from a chemically defined medium were resuspended in 0.01 M phosphate buffer of pH 7.3. Electron microscopy showed that 90 min of exposure effectively ruptured the outer envelope, freeing it from the cells as small flakes. Both zonal centrifugation in sucrose gradients and centrifugation in isopycnic KBr and CsCl gradients could be used to separate the outer envelope from the axial filaments and protoplasmic cylinders. The latter method resulting in higher yields of purified envelope with the particular protocols used. Thin sections of isolated outer envelope showed the same trilaminar structure seen in sections of intact cells. The outer layers were 1.5 nm thick and appeared as single layers of electron-dense particles. The central electron-transparent layer was 2.0-2.5 nm thick and appeared structureless. The gross chemical composition of the purified outer envelope was 47% protein, 27% carbohydrate, and 23% lipid. Colorimetric carbohydrate determinations revealed hexose, pentose, and 6-deoxyhexose; hexosamine was identified during amino acid analysis. Muramic acid, heptose, and 2-keto-3-deoxyoctonate were not detected. Thin-layer chromatography revealed only polar lipids, about 98% phosphatidylethanolamine and 2% lysophosphatidylethanolamine. Fatty acids identified by gas-liquid chromatography were octadecanoic, octadecenoic, hexadecanoic, and hexadecenoic. Amino acid analysis revealed 17 amino acids, histidine and glutamic acid being most abundant. The outer envelope was interpreted to be comparable with the outer double-track layer found in the cell covering of gram-negative eubacteria.

Inmunización contra la leptospirosis: ensayo de vacuna en cricetos con antígenos de células enteras muertas por calor y de envoltura externa / Immunization against leptospirosis: vaccine trial with heat-killed whole-cell and outer envelope antigens in hamsters

Se evaluó la utilidad, como vacuna, de dos preparaciones antigénicas de leptospiras. Las suspensiones de células enteras sometidas a calentamiento demostraros ser muy eficaces para proteger a los cricetos contra la leptospirosis experimental (AU)

Inmunización contra la leptospirosis: continuación de las pruebas realizadas en cricetos con vacunas obtenidas de cepas aisladas en Barbados / Immunization against leptospirosis: continued vaccine trials in hamsters using strains isolated from Barbados

Suspensiones calentadas de células enteras provenientes de cepas copenhageni del serotipo de Leptospira interrogans, aisladas en el campo, en Barbados, demostraron ser inmunógenos protectores contra la leptospirosis experimental (AU)