Quantitative analysis of light-phase restricted feeding reveals metabolic dyssynchrony in mice.

BACKGROUND: Considerable evidence suggests that the time of day at which calories are consumed markedly impacts body weight gain and adiposity. However, a precise quantification of energy balance parameters during controlled animal studies enforcing time-of-day-restricted feeding is currently lacking in the absence of direct human interaction. OBJECTIVE: The purpose of the present study was therefore to quantify the effects of restricted feeding during the light (sleep)-phase in a fully-automated, computer-controlled comprehensive laboratory animal monitoring system (CLAMS) designed to modulate food access in a time-of-day-dependent manner. Energy balance, gene expression (within metabolically relevant tissues), humoral factors and body weight were assessed. RESULTS: We report that relative to mice fed only during the dark (active)-phase, light (sleep)-phase fed mice: (1) consume a large meal upon initiation of food availability; (2) consume greater total calories per day; (3) exhibit a higher respiratory exchange ratio (indicative of decreased reliance on lipid/fatty acid oxidation); (4) exhibit tissue-specific alterations in the phases and amplitudes of circadian clock and metabolic genes in metabolically active tissues (greatest phase differences observed in the liver and diminution of amplitudes in epididymal fat, gastrocnemius muscle and heart); (5) exhibit diminished amplitude in humoral factor diurnal variations (for example, corticosterone); and (6) exhibit greater weight gain within 9 days of restricted feeding. CONCLUSIONS: Collectively, these data suggest that weight gain following light (sleep)-phase restricted feeding is associated with significant alterations in energy balance, as well as dyssynchrony between metabolically active organs.

Does acute exercise affect the susceptibility of low density lipoprotein to oxidation?

This study describes the effect of an acute exercise bout on the susceptibility of isolated low density lipoprotein (LDL) to in vitro oxidation. LDL was isolated from 23 subjects (exercisers, n = 11; sedentary, n = 12) immediately before and after a single bout of exercise (30 min of treadmill work at 55% & 70% peak oxygen consumption (VO2 peak) for exercisers and sedentary, respectively). A statistically significant decrease in lag time for LDL oxidation was observed following exercise compared to baseline (96.1+/-23.5 min vs. 92.1+/-23.3 minutes; n = 23, p < or = .03) using a 5 microM copper system. There was a statistically significant increase in plasma myeloperoxidase (MPO) levels following exercise compared to baseline values ( 1.58+/-.91 ng/dl versus 2.08+/-1.2 ng/dl; n = 12, p < or = .03). These results suggest that the 30 min exercise bout at a moderate intensity and duration was a sufficient oxidative stress to increase the susceptibility of LDL to in vitro oxidation. Additionally, the exercise bout appeared to activate neutrophils, subsequently releasing MPO protein.

Experimental Brucella abortus infection in pigs.

Sixteen pigs inoculated by the intra-conjunctival, intravenous or subcutaneous routes with Brucella abortus Strain 544 developed a short-lived infection usually accompanied by conjunctival and vaginal excretion of the organism for up to 99 days post-inoculation. Serological tests performed by the agglutination, complement fixation, Rose Bengal plate, antiglobulin, immunodiffusion or ELISA procedures with B. abortus antigens disclosed wide variations in the antibody responses of individual animals. In some cases the serological tests were negative even though the animal was shown to be excreting B. abortus. The intradermal test for delayed hypersensitivity to Brucella antigens gave more consistent results, especially when supported by histological evaluation of the skin reactions.

Development of improved methods for the transport and isolation of Haemophilus somnus.

The survival of several strains of Haemophilus somnus under various simulated transport conditions was investigated. Recovery of H somnus from alginate swabs kept at room temperature was possible for up to 27 hours after sampling, but this period could be extended to 72 hours if the swabs were refrigerated. Storage of swabs in transport media did not prolong survival time significantly but did increase the number of bacterial contaminants, thus making recovery of H somnus less likely. The sensitivity of several strains of H somnus to a number of dyes, antibiotics and other antimicrobial agents was determined and a selective isolation medium then formulated. This medium which consisted of brain heart infusion agar supplemented with 5 per cent ovine blood, 5 per cent equine serum, 0.5 per cent yeast extract, cycloheximide (100 micrograms ml-1) and lincomycin (3 micrograms ml-1), facilitated the isolation of H somnus from contaminated material. However, while this medium was effective against many contaminants, it did not prevent swarming by Proteus species.

Disc electrophoresis of phenol:acetic acid:water-soluble proteins for the identification of Yersinia species.

Disc electrophoresis of phenol:acetic acid:water extracts of Yersinia pestis, Y produced pseudotuberculosis, Y enterocolitica, Y philomiragia and Y ruckeri protein separation patterns characteristic of each species. The patterns produced by Y pestis, Y pseudotuberculosis, Y enterocolitica and Y ruckeri showed features in common. Those given by Y philomiragia strains were quite distinctive and showed little similarity to the other Yersinia species. All Y enterocolitica strains produced similar patterns irrespective of biochemical properties. Strains classified as Y intermedia or Y enterocolitica-like produced patterns indistinguishable from those given by Y enterocolitica.

Characterization of the major antigens of Haemophilus equigenitalis (contagious equine metritis organism).

Immunoelectrophoresis of ultrasonically disrupted Haemophilus equigenitalis (contagious equine metritis organism) cells against rabbit and equine antisera disclosed at least 11 precipitating antigens. Two of these, a polysaccharide and a lipopolysaccharide-protein complex, were of high molecular weight and located on the cell surface. The remaining antigens were intracellular and were small- to medium-sized proteins. The surface antigens were the most significant in relation to the serological response in infected horses. They also reacted with sera from apparently healthy cattle, but the reason for this was not determined. No serological cross-reaction between H. equigenitalis and species of Achromobacter and Moraxella was detected.

Isolation and properties of an RNA fraction present in Brucella culture supernatants.

The supernatant fluids of batch and continuous cultures of Brucella strains contained up to 100 mg/l of soluble RNA which could be recovered by precipitation with lysozyme, This RNA fraction had many of the properties of ribosomal RNA and was single-stranded, sensitive to ribonuclease, with an approximate sedimentation constant of 5S, a molecular weight of about 35000 daltons and an adenine; guanine; cytosine; uracil content of 17.5; 26.5; 33; 23 mol% respectively. RNA fractions from lysozyme precipitates evoked high titres of Brucella agglutinins on injection into rabbits and induced acute inflammatory responses in guinea-pig skin. Highly purified RNA fractions prepared by phenol extraction of lysozyme precipitates did not evoke antibodies to Brucella abortus.

Characterization of Yersinia enterocolitica strains isolated from cattle, sheep and pigs in the United Kingdom.

The properties of 48 cultures identified as Yersinia enterocolitica or Y. enterocolitica-like organisms, including Y. frederiksenii, Y. intermedia and Y. kristensenii, were examined. Of these, 39 were isolated from faeces of apparently healthy pigs, five from healthy cattle, one from an aborted bovine fetus, one from an aborted lamb and one from a lamb suffering from acute enteritis. Most isolates from healthy animals were of Y. enterocolitica biotype 1 or Y. intermedia and belonged to O serogroups not usually associated with disease in man or animals. The isolates from abortion or enteritis cases were of Y. enterocolitica biotypes 3, 4 and 5 and belonged to the pathogenic serogroups 0:5b and 0:2a, 2b, 3. No organisms of serogroup 0:9 were found.

Reporting elder abuse: limitations of statutes.

When it comes to protecting abused elders and determining physicians' legal responsibilities, each state has its own legislation - there is no federal policy. In the extreme, this can mean 50 variations on a theme. Few laws clearly delineate differences between neglect and abuse, nor do they provide graduated remedies to address differing degrees of severity. Even though many states have passed mandatory reporting laws, most provide little or no funding for meaningful intervention. All physicians should become familiar with applicable elder abuse laws and the procedure for referring a suspected case. This presentation of our findings is necessarily brief and should not take the place of familiarity with the legislation in the reader's own state. A copy of relevant state legislation generally can be obtained from the local state legislator's office or law library.

Observations on serological cross-reactions between smooth Brucella species and organisms of other genera.

Serological cross-reactions have been demonstrated between smooth Brucella species and Escherichia coli 0:116 and 0:157, Salmonella serotypes of Kauffmann-White group N, Pseudomonas maltophilia and Yersinia enterocolitica 0:9 and 0:16. All of these organisms may evoke significant titres of cross-reacting antibodies in cattle and pigs inoculated by parenteral routes. E. coli 0:157, Salmonella urbana and Y. enterocolitica 0:9 evoked substantial titres of cross-reacting antibodies in cattle inoculated by the oral route with live organisms. Only Y. enterocolitica 0:9 was effective in evoking cross-reacting antibodies to Brucella in pigs inoculated by the same route. Differentiation of cross-reacting and homologous antibodies to Brucella was difficult and was not accomplished consistently by any single test.

The interaction of Brucella cell surface components with plant agglutinins.

Cells of all Brucella species were agglutinated by the basic protein-reactive lectins of Mangifera indica and Persea americana. Cells of non-smooth strains including B. ovis and B. canis but not smooth strains were also agglutinated by concanavalin A. These lectins also reacted in a similar pattern with lipopolysaccharide extracts of these organisms. The lectin from Bandeiraea simplicifolia precipitated with the lipopolysaccharide antigens of smooth Brucella organisms and with those of serologically cross-reactive strains of Escherichia coli, Pseudomonas maltophilia, Salmonella and Yersinia enterocolitica but not with antigenically unrelated strains.

Arthropathy associated with Brucella abortus strain 19 vaccination in cattle. I. Examination of field cases.

Thirty cows presenting with lameness and persistent serological reactions to Brucella abortus had chronic granulomatous arthropathy of the femorotibial and occasionally other joints. Attempts to culture Brucella or other pathogens gave negative results but organisms of Brucella morphology were seen in fluorescent antibody-stained cryostat sections of synovial tissue. The synovial fluids contained high titres of antibodies to B. abortus and Yersinia enterocolitica O:9 and had elevated total protein and immunoglobulin concentrations showing an oligoclonal electrophoretic profile. Immune complexes and rheumatoid factor were detected in some of the fluids.

Arthropathy associated with Brucella abortus strain 19 vaccination in cattle. II. Experimental studies.

Attempts to reproduce in calves the arthropathy associated with Brucella abortus strain 19 (S19) vaccination by direct intra-articular injection of S19 or virulent Brucella cells were unsuccessful. Intra-articular injection of rabbits and a calf with immune complexes isolated from the synovial fluid of a field case produced clinical and histological signs of arthropathy accompanied by the development of rheumatoid factor.

Experimental Haemophilus somnus infection in pregnant cattle.

Of five pregnant cows inoculated intravenously with 5 X 10(8) viable 'Haemophilus somnus', one aborted within 5 days and excreted 'H. somnus' from the vagina for a further 7 weeks. A second cow proceeded to full term parturition but both it and its apparently healthy calf persistently excreted 'H. somnus'. The other animals underwent normal full term calvings and 'H. somnus' was not isolated from them or their calves. Lesions attributable to 'H. somnus' were detected only in the aborted fetus which showed an acute generalized inflammatory cell response consistent with a systemic Gram-negative bacterial infection. 'H. somnus' was isolated from all fetal tissues, including the placenta. The fetus and placenta also showed evidence of damage prior to inoculation. The placental damage may have predisposed the fetus and placenta to infection with 'H. somnus'. The placental epithelial cells contained intracytoplasmic organisms with the morphological and antigenic properties of 'H. somnus'.