Biomedical subjects

C D Wilson

Publications and source records attributed to C D Wilson.

At least 19 recordsLinked to original sources

PubMed1998

In vivo IL-1beta-induced modulation of G-protein alphaO subunit subclass in the hypothalamic ventromedial nucleus: implications to IL-1beta-associated anorexia.

The intracerebroventricular (i.c.v.) administration of interleukin-1beta (IL-1beta) induces anorexia in rats at doses that yield estimated pathophysiological concentrations in the cerebrospinal fluid. IL-1beta also induces anorexia when administered into the hypothalamic ventromedial nucleus (VMN), an important brain site for the control of feeding. A variety of guanine nucleotide binding protein (G-protein) coupled receptors (e. g., for neurotransmitters and neuropeptides) participate in the integrative regulation of feeding. Our previous studies reported that the VMN G-protein alphaO common subunit subclass is involved in the control of normal feeding, and that IL-1beta modulates calcium channel currents via a pertussis toxin (PTX)-sensitive G-protein (GalphaO/Galphai). Here, we examined the profile of GalphaO protein expression in the hypothalamic VMN during IL-1beta-induced anorexia. Intracerebroventricular microinfusion of IL-1beta (0.5 to 8.0 ng/24 h for 72 h) into the third cerebral ventricle dose-dependently induced anorexia (p<0.001) and decreased the VMN GalphaO common protein levels (p<0.001). Heat-inactivated IL-1beta and IL-1beta plus IL-1 receptor antagonist (a competitive inhibitor of IL-1beta action) had no effect on food intake or on VMN GalphaO common protein content. RT-PCR analysis of VMN RNA from IL-1beta-treated rats generated an expression profile for GalphaO common subunit; however, no modulation at the mRNA level was observed. The results suggest that anorexia induced by the central administration of IL-1beta involves modification of G-protein alphaO common subunit profile in the central nervous system.

Animals↗

PubMed1998

Consumer acceptance of vegetarian sweet potato products intended for space missions.

Sweet potato is one of the crops selected for NASA's Advanced Life Support Program for potential long-duration lunar/Mars missions. This article presents recipes of products made from sweet potato and determines the consumer acceptability of products containing from 6% to 20% sweet potato on a dry weight basis. These products were developed for use in nutritious and palatable meals for future space explorers. Sensory evaluation (appearance/color, aroma, texture, flavor/taste, and overall acceptability) studies were conducted to determine the consumer acceptability of vegetarian products made with sweet potato using panelists at NASA/Johnson Space Center in Houston, TX. None of these products including the controls, contained any ingredient of animal origin with the exception of sweet potato pie. A 9-point hedonic scale (9 being like extremely and 1 being dislike extremely) was used to evaluate 10 products and compare them to similar commercially available products used as controls. The products tested were pancakes, waffles, tortillas, bread, pie, pound cake, pasta, vegetable patties, doughnuts, and pretzels. All of the products were either liked moderately or liked slightly with the exception of the sweet potato vegetable patties, which were neither liked nor disliked. Mean comparisons of sensory scores of sweet potato recipes and their controls were accomplished by using the Student t-test. Because of their nutritional adequacy and consumer acceptability, these products are being recommended to NASA's Advanced Life Support Program for inclusion in a vegetarian menu plan designed for lunar/Mars space missions.

Diet, Vegetarian↗

PubMed1998

Sweet potato in a vegetarian menu plan for NASA's Advanced Life Support Program.

Sweet potato has been selected as one of the crops for NASA's Advanced Life Support Program. Sweet potato primarily provides carbohydrate--an important energy source, beta-carotene, and ascorbic acid to a space diet. This study focuses on menus incorporating two sets of sweet potato recipes developed at Tuskegee University. One set includes recipes for 10 vegetarian products containing fom 6% to 20% sweet potato on a dry weight basis (pancakes, waffles, tortillas, bread, pie, pound cake, pasta, vegetable patties, doughnuts, and pretzels) that have been formulated, subjected to sensory evaluation, and determined to be acceptable. These recipes and the other set of recipes, not tested organoleptically, were substituted in a 10-day vegetarian menu plan developed by the American Institute of Biological Sciences (AIBS) Kennedy Space Center Biomass Processing Technical Panel. At least one recipe containing sweet potato was included in each meal. An analysis of the nutritional quality of this menu compared to the original AIBS menu found improved beta-carotene content (p<0.05). All other nutrients, except vitamin B6, and calories were equal and in some instances greater than those listed for NASA's Controlled Ecological Life Support Systems RDA. These results suggest that sweet potato products can be used successfully in menus developed for space with the added benefit of increased nutrient value and dietary variety.

Diet, Vegetarian↗

PubMed1997

Expression of the brain creatine kinase gene is low in neuroblastoma cell lines.

The cytoplasmic creatine kinase (CKB) enzyme has a central role in the regeneration of ATP in the brain. We have shown previously that CKB mRNA levels in cultured primary rat brain astrocytes and oligodendrocytes are much higher than in primary neurons. It has been suggested that high CKB expression is essential for the energy-demanding functions of glial cells. Conversely, CKB may be repressed in most neuronal cells; however, CKB protein has previously been detected by immunohistochemistry in several distinct groups of neurons in the adult rodent brain. Presently, little is known of the factors responsible for the high CKB expression in glia and possible repression in neurons. In this report, we investigated if low CKB mRNA was characteristic of some established neuronal cell lines. CKB mRNA was found to be extremely low in mouse C1300 neuroblastomas NS20Y and N1E-115 but 10-fold higher in NG108-15, a hybrid cell composed of a C1300 neuroblastoma and a rat C6 glioma. Since we showed NG108-15 contained only rat CKB mRNA transcribed from the C6 glioma CKB gene, expression of CKB mRNA may be a manifestation of a glial property in NG108-15 cells. However, CKB mRNA expression in NG108-15 appeared not to be fully activated since it was still 5-fold lower than in (parental) C6 glioma and 10-fold lower than in cellular RNA from either total rat brain or cultured primary astrocytes. When neuronal differentiation was increased in NS20Y and N1E-115 by treating cells with prostaglandin E1 and theophylline, the extremely low CKB mRNA level was not significantly changed. In a comparative study, the CKB mRNA levels in NS20Y, N1E-115 and neuronal RT4-B8 and RT4-E5 cells (from the rat RT4 peripheral neurotumor) were at least 50-fold lower than that in C6 glioma and 100-fold lower than in cultured primary astrocytes. These cell lines may provide a system for the identification of factors involved in the possible repression of CKB in many neuronal cells.

Animals↗

PubMed1997

Expression of the brain creatine kinase gene in rat RT4 peripheral neurotumor cell lines and its modulation by cell confluence.

Creatine kinases (CK) catalyze the reversible transfer of a high energy phosphate group between creatine phosphate and ADP to regenerate ATP in cell types where the requirements for ATP are extensive and/or sudden. Previously, we have shown in primary rat brain cell cultures that brain CK (CKB) mRNA levels are highest in astrocytes and oligodendrocytes and much lower in neuronal cells. However, little is known of the factors which regulate CKB expression in the central nervous system and peripheral nervous system. To begin to investigate these factors, we asked in this report (1) if this pattern of CKB expression was also characteristic of some established glial and neuronal cell lines derived from the PNS; (2) whether CKB expression could be rapidly modulated by culture conditions, and (3) if CKB is expressed in cells with characteristics of glial cell progenitors. In subconfluent cells, CKB mRNA and enzyme activity were found to be high in both the rat RT4 peripheral neurotumor stem cell RT4-AC36A and its glial cell derivative RT4-D6. Conversely, CKB mRNA and activity were 5- and 8-fold lower, respectively, in the neuronal derivative RT4-E5 and, more dramatically, CKB was undetectable in neuronal RT4-B8 cells. Maintaining RT4-D6 glial cells at confluence rapidly increased CKB enzyme activity by 7-fold, such that D6 cells contained about 25% of the CKB level in lysates prepared from either whole adult rat brain or primary cultures of rat brain astrocytes. The levels of CKB mRNA and immunoreactive protein were also correspondingly increased in confluent D6 cells. These confluence-mediated increases in CKB appeared to be due to cell-cell contact and not the depletion of serum growth factors or an increase in intracellular cAMP. This study indicates that CKB expression is highest in cells displaying glial properties and can be rapidly modulated by appropriate culture conditions. The results are discussed in relation to the factors which may regulate CKB expression in vivo.

Animals↗

PubMed1996

Anorexia induced by chronic central administration of cytokines at estimated pathophysiological concentrations.

Interleukin-1 beta (IL-1 beta), IL-6, IL-8, and tumor necrosis factor-alpha (TNF-alpha) induce acute anorexia by direct action in the central nervous system (CNS) at estimated pathophysiological concentrations reported in the cerebrospinal fluid (CSF). Cytokine-induced anorexia may also participate in the long-term anorexia observed during disease. Here, we studied the effects of chronic intracerebroventricular (ICV) microinfusion (through osmotic minipumps) of various cytokines on feeding and drinking in rats. The results show: IL-1 beta decreased nighttime feeding dose-dependently (with 0.5, 1.0, 2.0 and 8.0 ng/24 h, n > or = 8/group). The decrease of feeding and corresponding decrease of body weight persisted during the 7-day infusion. Total daily food intake decrease was less prominent relative to the nighttime decrease because daytime food intake slightly increased. Feeding and body weight increased toward baseline following the end of the IL-1 beta infusion. ICV microinfusion of heat-inactivated IL-1 beta or IL-1 beta plus IL-1 receptor antagonist had no effect, suggesting specificity of action of IL-1 beta. Water intake did not decrease in any IL-1 beta-treated group, suggesting specificity on feeding. Chronic ICV administration of TNF-alpha (20, 100, or 300 ng/24 h), IL-6 (100 ng/24 h), or IL-8 (20 ng/24 h) was significantly less effective than IL-1 beta in inducing behavioral modifications. The results suggest that IL-1 beta, at doses that yield estimated pathophysiological concentrations in the CSF, is capable of inducing long-term anorexia and this effect may participate in the anorexia observed during chronic disease.

Animals↗

PubMed1995

Antisense oligodeoxynucleotides to G-protein alpha-subunit subclasses identify a transductional requirement for the modulation of normal feeding dependent on G alpha OA subunit.

A variety of G-protein-coupled receptors are proposed to participate in the modulation of ingestive behavior and in the mode of action of antiobesity drugs. In the present study, we investigated the involvement of G-protein alpha-subunit subclasses (molecular transducers of multiple chemical signals) in the control of ingestive behavior. We report here that the chronic intracerebroventricular (i.c.v.) microinfusion for 72 h (via osmotic minipumps) with antisense phosphothio-oligodeoxynucleotides corresponding to G-protein alpha-subunitO common (to OA and OB) and OA subclasses decrease the nighttime food intake without affecting water intake in rats. Computerized analyses of the microstructure of feeding indicate that the G alpha OA antisense depresses feeding by reducing meal frequency, while meal size and meal duration increased slightly, but not significantly. The effects of G alpha O common and G alpha OA antisense on feeding are specific since the chronic i.c.v. microinfusion of sense to G alpha O common or G alpha OA, antisense to the related subclass G alpha OB, and antisense to other G-protein alpha-subunits (G alpha S, G alpha Q, G alpha 11 and G alpha i common) had no effect on food or water intake. The observed effects by G alpha O common and G alpha OA antisense imply a direct action in the central nervous system since the chronic subcutaneous microinfusion of G alpha O common and G alpha OA antisense in doses equivalent to two-fold higher relative to those administered centrally had no effect on food intake. The chronic microinfusion of G alpha O common antisense drastically decreased the levels of G alpha O protein detected in immunoblots of hypothalamic ventromedial nuclei. The results suggest that the G-protein alpha-subunit subclass G alpha OA is critical for the integrative modulation of normal feeding behavior, and that changes in its activity may be associated with modifications of feeding. These studies also show a novel approach to study the molecular basis of specific behaviors by manipulating elements of the transductional systems.

Animals↗

PubMed1993

Expression of the rat brain creatine kinase gene in C6 glioma cells.

We have recently shown that while brain creatine kinase (CKB) mRNA was detectable in RNA from cultured primary rat brain neurons, CKB mRNA was about 15-fold higher in primary astrocytes and 17-fold higher in oligodendrocytes (Molloy et al., J Neurochem 59:1925-1932, 1992). To begin to understand the molecular mechanisms responsible for brain glial cells containing the highest levels of CKB mRNA in the body, we have examined the expression of rat CKB mRNA in established C6 glioma cells. RNase-protection analysis showed the endogenous CKB mRNA levels in exponentially growing C6 were high and measured 50% of that in total RNA from rat brain lysate and 60% of that in cultured primary astrocytes and oligodendrocytes. The 5' and 3' ends of CKB mRNA in C6 were mapped to the same nucleotides as CKB mRNA from rat brain, indicating that the sites of in vivo transcription initiation and termination/polyadenylation of CKB mRNA in C6 are the same as in total rat brain RNA. The level of CKB enzyme activity in C6 whole cell lysates was among the highest of the glial cell lines which we measured. All creatine kinase enzyme activity present in C6 was found in the dimeric CKB isoform (BB), which is characteristic of CKB expression in the brain. A 2.9 kb gene fragment containing the basal CKB promoter and far-upstream 5' sequences was cloned upstream of the chloramphenicol acetyltransferase (CAT) gene and transfected into C6 cells. CAT activity was readily detectable in C6 and mapping of the 5' end of the CAT mRNA showed that transcription was directed from the correct initiation site. Since we found C6 cells were difficult to transfect, conditions were established which both maximized transfection efficiency and maintained normal C6 cell morphology. These results should permit the future identification of the nuclear trans-acting factors and the cognate cis-acting regulatory elements responsible for high CKB mRNA expression in brain glial cells.

Animals↗

PubMed1992

Rat brain creatine kinase messenger RNA levels are high in primary cultures of brain astrocytes and oligodendrocytes and low in neurons.

Rat brain creatine kinase (CKB) gene expression is highest in the brain but is also detectable at lower levels in some other tissues. In the brain, the CKB enzyme is thought to be involved in the regeneration of ATP necessary for transport of ions and neurotransmitters. To understand the molecular events that lead to high CKB expression in the brain, we have determined the steady-state levels of CKB mRNA in homogeneous cultures of primary rat brain astrocytes, oligodendrocytes, and neurons. Northern blot analysis showed that whereas the 1.4-kb CKB mRNA was detectable in neurons, the level was about 17-fold higher in oligodendrocytes and 15-fold higher in astrocytes. The blots were hybridized with a CKB-specific 32P-antisense RNA probe, complementary to the 3' untranslated sequence of CKB, which hybridizes to CKB mRNA but not CKM mRNA. Also, the 5' and 3' ends of CKB mRNA from the glial cells were mapped, using exon-specific antisense probes in the RNase-protection assay, and were found to be the same in astrocytes and oligodendrocytes. This indicated that (a) the site of in vivo transcription initiation in astrocytes and oligodendrocytes was directed exclusively by the downstream, nonconcensus TTAA sequence at -25 bp in the CKB promoter that is also utilized by all other cell types that express CKB and (b) the 3' end of mature CKB mRNA was the same in astrocytes and oligodendrocytes. In addition, there was no detectable alternate splicing in exon 1, 2, or 8 of CKB mRNA in rat astrocytes and oligodendrocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

Weight control methods in high school wrestlers.

Severe weight control methods used by high school wrestlers have caused concern about these students' growth and athletic performance. There are minimal prevalence data on a few methods of weight control used by wrestlers and no information on the relationship to body fat measurements. Weight control methods and the percent body fat of wrestlers (n = 49) were compared to competitive squash players (n = 20) and noncompetitive jogging and fitness students (n = 38) at an independent secondary school. Wrestlers used dieting (p = 0.0002), binging (p = 0.026, vomiting (p = 0.046), sweating (p = 0.0001), and fluid restriction to less than 2 cups/day (p = 0.0014) significantly more often than controls (squash players and jogging/fitness students). There was no difference between the wrestlers' and controls' use of fasting (p = 0.5) or exercising (p = 0.1). Neither group reported using a diuretic or laxative during the sports seasons. Although the wrestlers' percent body fat was lower than controls (mean for wrestlers = 10.3 +/- 3.5%, mean for controls = 12.4 +/- 3.7%, p = 0.01), wrestlers perceived their mean ideal weight to be less than their present weight (wrestlers = -1.56 +/- 6.20 lb, controls = +1.92 +/- 9.49 lb, p = 0.03). The methods of weight control practiced could potentially impair an adolescent's growth and development as well as increase the risk of dehydration or electrolyte imbalance during competition.

Adolescent↗

PubMed1986

Pharmacokinetics of cefoperazone in the cow by the intramammary route and its effect on mastitis pathogens in vitro.

The pharmacokinetic and microbiological properties of a new third generation cephalosporin, cefoperazone, when given by the intramammary route to the cow are described. Cefoperazone is excreted from the udder over a three- to five-day period following a single infusion of 250 mg in an oil base into each of all four quarters. By the fifth milking after treatment the mean bucket (composite) concentration of cefoperazone was below 0.01 microgram/ml. The minimal inhibitory concentrations for 470 pathogens isolated from cases of mastitis were determined. A few exotic species were resistant but all the usual isolates were sensitive. No signs of transferable drug resistance from known multiple drug-resistant strains were detected.

Animals↗

PubMed1986

Observations on the incidence of clinical bovine mastitis in non-lactating cows in England and Wales.

Epidemiological features of clinical mastitis in dry cows from a three year prospective study are described. Two hundred and seventy-three herds in England and Wales participated in the first year (1980) and 209 and 159 of them continued in the study in the subsequent two years. Clinical mastitis was recorded in 1.5 per cent of cows during the dry period in each of the three years. These cases represented between 3.6 and 4.2 per cent of samples from all clinical cases examined. The incidence of clinical mastitis in dry cows increased during the winter housing period (October to March), a peak occurring at the end of this period. A secondary peak in incidence was recorded in August. Streptococcus uberis was the predominant pathogen. Variations in the monthly incidences of cases associated with the major mastitis pathogens were observed. A greater proportion of cases which occurred during the dry period exhibited systemic signs than of cases which occurred during lactation, with the exception of cases associated with Escherichia coli. The risk of clinical mastitis was apparently higher during the last 30 days of the dry period than during the earlier stages of the dry period.

Animals↗

PubMed1986

Incidence of clinical mastitis in a cohort of British dairy herds.

A three-year survey to determine the incidence of clinical mastitis and the associated bacteria in dairy herds in England and Wales is described. Escherichia coli was the predominant organism in each year. Streptococcus uberis and Staphylococcus aureus were important for part for each year. The annual incidence of mastitis declined from 54.6 cases per 100 cows in 1980 to 41.2 in 1982. The incidence increased with age and declined with increasing herd size. The culling rate due solely to mastitis was 3 per cent. Strep uberis was the pathogen most frequently isolated from clinical cases which occurred in the dry period. Thirty per cent of all cases recurred at least once and staphylococcal cases exhibited the highest frequency of recurrence.

Animals↗

PubMed1986

Field trials with cefoperazone in the treatment of bovine clinical mastitis.

A single dose of 250 mg cefoperazone in an oil based suspension infused into bovine quarters suffering from clinical mastitis resulted in an overall clinical cure of 82 per cent in 597 cases, as assessed by veterinarians in four countries (Sweden, Denmark, France and the United Kingdom). Of those cases for which adequate bacteriological data were available 69 per cent of 434 cases were cured. There were no reports of adverse reactions following therapy of an affected quarter. The introduction of single dose treatment represents an advance in mastitis therapy as it offers a simpler and shorter treatment than most present day mastitis therapeutics when used according to recommendations.

Animals↗

PubMed1983

Eradication of Mycoplasma bovis infection from a dairy herd in Great Britain.

Mycoplasma bovis infection was eradicated from a naturally infected dairy herd in Great Britain by a programme of identification, segregation and culling of infected animals. A series of group and whole milking herd tests was carried out over a period of 15 months, followed by a whole herd nasal swabbing. Cows were also sampled after calving and at drying off and bulk tanks were sampled at weekly intervals during the same period and for a further nine months. Fifty-nine cows were identified as excretors, the majority in group or herd tests, but five after calving and three at drying off. Eight of the original clinical cases were retained in the herd, after repeated negative test results. Bulk tank sampling was found to be extremely useful in detecting infection even down to one cow in a milking herd of 300. The value of milking hygiene and the indications for eradication are also discussed.

Animals↗

PubMed1983

Toxic shock syndrome and diaphragm use.

A case of toxic shock syndrome (TSS) associated with diaphragm use is presented. Adolescents who use a diaphragm should be informed of the symptoms of TSS, and those with the syndrome should be questioned about diaphragm use.

Adolescent↗

PubMed1983

Penicillin (cloxacillin)-tolerant Staphylococcus aureus from bovine mastitis: identification and lack of correlation between tolerance in vitro and response to therapy in vivo.

Twenty-four isolates of Staphylococcus aureus from naturally occurring cases of bovine mastitis were examined in vitro for resistance to cloxacillin. All strains produced penicillinase and none showed intrinsic resistance (methicillin resistance) to cloxacillin. The minimum inhibitory concentration of cloxacillin for all these strains was normal (low) but differences were found between them in their sensitivities to the bactericidal action. Three were considered to be tolerant to cloxacillin and a further five possibly so. In a mouse model of mastitis there was no difference in the response to intramammary therapy with cloxacillin between cloxacillin-sensitive or tolerant strains of S aureus and a known methicillin-resistant strain was similarly sensitive to cloxacillin therapy in vivo. It is concluded that cloxacillin tolerance may have little clinical significance in mastitis therapy.

Acute Disease↗

PubMed1981

A comparison of national mastitis surveys in Great Britain and the Netherlands.

The results of a national survey of mastitis carried out in 1977 in Great Britain are compared with similar surveys carried out in the Netherlands. The results are very similar although the average herd-size was much higher in the British survey. The advantage of teat-dipping and dry-cow therapy was demonstrated. Both surveys showed a decrease in infection level with increasing herd-size but the reverse was true with increased age. The value of individual bulk-milk cell counts as an indicator of infection level is questioned.

Age Factors↗