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PubMed2003

Effects of butyrate on apoptosis in the pig colon and its consequences for skatole formation and tissue accumulation.

Evidence exists that butyrate inhibits apoptosis of colon crypt cells in vivo so that less tryptophan from cell debris is available for skatole formation by microbes in the pig colon. In this study, potato starch containing a high proportion of resistant starch was fed to test the hypothesis that increased butyrate formation will occur in the colon and contribute to reduced epithelial cell apoptosis, thus leading to reduced skatole formation and absorption. Two groups of six barrows were provided with catheters in the jugular vein and fed either a ration with pregelatinized starch (high ileal digestibility; controls) or potato starch (low ileal digestibility; PS) as the main carbohydrate. All pigs were fed 31 MJ of metabolizable energy and 381 g of crude protein per day. The controls were fed for 19 d. The PS group received the same control ration for 10 d, and then changed to the PS ration. The total feeding period of PS consisted of a 5 d adaptation period followed by another 19 d. In the continously sampled feces, pH, short chain fatty acids, and skatole were determined. Skatole was additionally measured in blood plasma that was sampled daily. After killing barrows at the end of the feeding period, fat tissue for skatole measurement and colon tissue for histological quantification of mitosis and apoptosis were obtained. Feeding potato starch led to a rapid 2.2 fold increase of fecal butyrate when compared both with the control period of the PS group and the control group (P < 0.001). PS feeding resulted in a decrease in pH from 7.3 to 5.3 (P < 0.001) and apoptosis from 2.06 cells/crypt to 0.90 cells (P < 0.01), whereas there was no change in mitosis. Consequently, skatole decreased both in feces (controls vs PS group: 120.0 vs 1.9 microg/g; P < 0.001) and in blood plasma (1.6 vs 0.2 ng/mL; P < 0.001). The mean concentration of skatole in fat tissue was 167 ng/g tissue in controls, and below the detection limit (0.8 ng/g) in the PS group (P < 0.001). It is concluded that butyrate-dependent inhibition of apoptosis in the colon due to potato starch feeding efficiently inhibits skatole production in barrows. Because of the depressed skatole levels, improved sensory quality of pork is possible.

Animal Feed↗

PubMed2004

Effect of feed intake on endogenous losses and amino acid and energy digestibility by growing pigs.

An experiment was conducted to determine the effect of feed intake (FI) on endogenous losses and the digestibility of CP and AA by growing pigs. Six growing barrows (initial BW = 70.3 kg) had a T-cannula installed in the distal ileum and were used in a 6 x 6 Latin square design. A soybean meal cornstarch-based diet and a N-free diet were formulated. Chromic oxide (0.25%; as-fed basis) was included in both diets as an inert marker. Each diet was provided at three different levels of FI. Feed intake level 1 was equal to the estimated energy requirement for maintenance of the pigs, whereas levels 2 and 3 were two or three times this amount, respectively. Each experimental period lasted 7 d. The initial 4 d of each period comprised an adaptation period to the experimental diets. On d 5, fecal samples were collected, while ileal digesta were collected during two 10-h periods on d 6 and 7. Between each experimental period, a corn-soybean meal-based diet (16% CP) was fed to all pigs for 7 d. The basal ileal endogenous losses (IAA(end)) of CP and AA were measured for each level of FI from pigs fed the N-free diet. Likewise, the apparent (AID) and standardized (SID) ileal digestibility coefficients for CP and AA in soybean meal were calculated for each level of FI. The total-tract digestibility coefficient of energy in the soybean meal-based diet also was calculated. The AID for CP and all indispensable AA except Lys, Met, and Thr increased (P < or =0.055) as FI increased. The IAA(end) of CP and all AA except Pro decreased linearly (P < 0.05) as FI increased when expressed as g/kg of DMI; however, the total daily IAA(end) increased as FI increased (linear, P < or =0.056) for all AA, except for Phe, Thr, Trp, Val, Cys, Gly, and Ser. The AA composition (% of CP) of endogenous protein was not affected by the level of FI, except for Arg, Thr, Pro, and Ser. As FI increased, the SID decreased linearly (P < 0.04) for CP and all AA, except Arg, Trp, Asp, Pro, and Tyr. The total-tract digestibility of energy was not influenced by the FI level. These results demonstrate that the FI level significantly influenced AID, SID, and IAA(end) for CP and AA. Therefore, pigs used to measure AA digestibility coefficients and IAA(end) should be fed at a level that is close to what is used under commercial conditions.

Amino Acids↗

PubMed2004

Excretion of major odor-causing and acidifying compounds in response to dietary supplementation of chicory inulin in growing pigs.

The excretion of major odor-causing and acidifying compounds in response to dietary supplementation of chicory inulin extract was investigated with six Yorkshire barrows, with an average initial BW of 30 kg, according to a balanced two-period cross-over design. The animals were fed a control diet containing no inulin extract and a treatment diet with 5% inulin extract (as-fed basis) at the expense of cornstarch. Each diet was formulated (as-fed basis) to contain 16% CP from corn (51%) and soybean meal (29%). Each experimental period lasted 14 d, with 10 d for dietary adaptation and 4 d for collection of fecal and urine samples. The fecal samples were analyzed for four major classes of odor-causing and acidifying compounds: 1) VFA; 2) N-containing compounds, including total N and ammonia; 3) volatile sulfides measured as hydrogen sulfide units; and 4) phenols and indoles, including p-cresol, indole, and skatole. Supplementation of chicory inulin at 5% had no effects on the fecal excretion of VFA (P = 0.29), ammonia (P = 0.96), total volatile sulfides (P = 0.56), p-cresol (P = 0.56), and indole (P = 0.75). Fecal excretion of total N (inulin = 6.13 vs. control = 5.10 g/kg DMI) was increased (P < 0.05), whereas urinary total N excretion (inulin = 15.1 vs. control = 16.4 g/[pig x d]) was not affected (P = 0.17) by the inulin supplementation compared with the control group. Furthermore, fecal excretion of skatole (inulin = 9.07 vs. control = 18.93 mg/kg DMI) was decreased (P < 0.05) by the inulin supplementation compared with the control group. In conclusion, dietary supplementation of 5% chicory inulin extract is effective in decreasing the fecal excretion of skatole in growing pigs fed corn and soybean meal diets.

Ammonia↗

PubMed1989

Influence of soybean meal and sorghum grain supplementation on intake, digesta kinetics, ruminal fermentation, site and extent of digestion and microbial protein synthesis in beef steers grazing blue grama rangeland.

Six beef steers (British x Brahman) cannulated at the rumen, duodenum and ileum (avg wt 334 kg) and three mature steers (British x British) cannulated at the esophagus were used in a replicated 3 x 3 latin square design and fed no supplement (C), .5 kg soybean meal (SBM) or .5 kg steam-flaked sorghum grain (SFS).head-1.d-1 (DM basis) while grazing blue grama rangeland. Periods of the latin square included a minimum of 14 d for adaptation and 11 d for esophageal masticate collection and digesta sampling. In September, October and November, respectively, forage collected by esophageally cannulated steers averaged 74.5, 88.8 and 71.0% grasses; 2.06, 1.53 and 1.77% N and 68.3, (P greater than .10) by treatment, but total N intake was greater (P less than .05) for SBM vs C and SFS treatments. No differences (P greater than .10) were detected among treatments in OM, NDF, ADF and N digestibilities in the rumen, small intestine or hindgut, but total tract OM digestibility was greater (P less than .10) for SBM and SFS than for C, and total tract N digestibility was greater (P less than .10) for SBM than for C or SFS. Duodenal ammonia N flow was greater (P less than .05) when SBM was fed that when SFS and C were fed, but microbial N and non-ammonia, non-microbial N flows and microbial efficiency were not altered by treatment. Likewise, ileal N flow was not affected (P greater than .10) by treatment. Particulate passage rate, gastrointestinal mean retention time, forage in vitro OM disappearance and in situ rate of forage NDF digestion also were not affected (P greater than .10) by treatments. Ruminal fluid volume was greater (P less than .05) for SFS vs SBM and C treatments, but no differences were noted in fluid dilution rate. Ruminal fluid ammonia concentration was greater (P less than .05) when SBM was fed than when SFS and C were fed (13.5, 9.9 and 8.7 mg/dl, respectively), whereas pH and total VFA concentrations were not different (P greater than .10). Proportion of acetate in ruminal fluid was less (P less than .10) for SBM and SFS than for C. Small amounts of supplemental SBM and SFS had little effect on forage intake, ruminal fermentation and site of digestion but both increased total tract OM digestion in steers grazing blue grama rangeland.

Animal Feed↗

PubMed1999

Quantitative studies on myelinated and unmyelinated nerve fibres in the interatrial septal region of aged rat hearts.

Intracardiac nerve fibres from the interatrial septum were studied quantitatively and qualitatively by electron microscopy of transversely sectioned nerve bundles in male Wistar rats of 4 and 24 months. No significant changes were found in the myelinated fibre diameters, myelinated axon diameters, myelin sheath thicknesses, g ratios, myelinated fibre areas, unmyelinated axon diameters and unmyelinated axon areas. However, there was evidence of structural changes to the nerve fibres and Schwann cells at 4 and 24 months, increasing in prevalence with age: some myelinated fibres showed infolds, disruptions and clefts of the myelin sheath and accumulation of electron dense myelin-like fragments in the axoplasm. Unmyelinated axons showed fewer changes in structure but also contained similar fragments in the axoplasm. The numbers of neurotubules and neurofilaments per microm2 in unmyelinated intracardiac axons was significantly greater than in those in samples of the cervical vagal trunk. This may be an adaptation to the continuous mechanical stress experienced by these intracardiac nerves. It is concluded that there is little structural evidence to suggest that the conductive properties of intracardiac nerve fibres are adversely affected in aged rats.

Aging↗

PubMed1999

Quantitative studies on myelinated and unmyelinated nerve fibres in the interatrial septal region of aged rat hearts.

Journal Article↗

PubMed1975

[The determination of chloride in plasma and serum (mercury(II)-thiocyanate method) with the Greiner Electronic Selective Analyzer GSA II (author's transl)].

1. A mercury(II)-thiocyanate method for the determination of chloride in plasma and serum was adapted for the Greiner Electronic Selective Analyzer GSA II. A sample blank value and a partial reagent blank value were determined by omitting thiocyanate from the control system. 2. The course of the reaction was investigated. For a reaction time of 350-500 s, the response was linear between 30 and 130 mmol/l. Between 90 and 110 mmol/l, the deviation between the actual and the theoretical value is less than 1%. 3. The calibration must be checked and, if necessary, restandardized; this is probably due to variable contamination of the reagents with chloride ions. 4. Haemolysis, lipaemia and bilirubin do not interfere. Protein has no effect on the course of the reaction. 5. At concentrations around 100 mmol/l, the in series precision, expressed as the variation coefficient (%), is 0.3-0.6% for aqueous solutions, 0.4-0.8% for liquid control sera, and 0.8-1.5% for lyophilized control sera. 6. No carry over was detectable from samples containing 150 to those containing 10 mmol/l.

Autoanalysis↗

PubMedDate not supplied

[A new oxidase method for analyzing L-lactate].

A new oxidase-coupled colorimetric method for analysis of L-lactate in biological fluids has been developed without use of peroxidase. The method is based on lactate oxidase-catalysed transformation of lactate to pyruvate which is determined photometrically in the next dye-producing reaction of 3-methyl-2-benzothiazolinone hydrazone (MBTH) in the presence of ferric ions. Sensitivity of the method is estimated as 0.1 micromole of analyte in 4-ml of reaction mixture. Linearity is observed in the range 0.1-1.0 micromole of L-lactate in sample (r = 0.99943; p < 0.0001). The developed method has been adapted for assay of L-lactic acid in kefirs and yogurts.

Catalysis↗

PubMed2003

[Epidemiological study of university students].

OBJECTIVE: to study prevalence rates of psychological distress among university students. METHOD: descriptive correlational research. Data gathered administering the brief version ( Argentine adaptation) of the Psychiatric Epidemiological Research Interview (PERI) to a sample of 1130 individuals studying at the University of Buenos Aires are presented. (Age Mean: 23 years old). RESULTS: 30 % of female students and 15 % of male ones can be considered at psychopathological RISK. Psychological symptoms of distress more frequently found are: anxiety, anger, irritability, violent attitudes or feelings. It can be said that 33% of female students and 19% of male ones express their wish to have a psychological interview with some professional of the University Health Center. Prevalence rates of distress are higher among participants who study Agronony, Philosophy and Literature and Medicine. CONCLUSION: data analyzed show the need to incorporate a psychophysical assessment of students matriculated in the University. Currently they pass only through a medical one. The University Health Center can provide preventive programmes as well as assistance and interventions related to rehabilitations.

Adult↗

PubMed2005

[The development and Assessment on the general quality of life intrument for Chinese people].

OBJECTIVE: To develop a general quality of life (QOL) instrument for Chinese in accordance with the Chinese culture and to assess its reliability, validity and sensitivity. METHODS: A 35-item QOL questionnaire(QOL-35) was developed with reference to the World Health Organization QOL questionnaire(WHO-100) and the 36-item medical outcomes study on short-form health status(SF-36). Thirty five items were divided into six domains (general, physical, independent, psychological, social, environment) and one item on QOL transition. The reliability of QOL-35 was assessed by a test-retest survey among 127 adults with an interval of 24-72 hours. The internal consistency and validity were evaluated by a survey on 135 adults from outpatients or general population, using QOL-35, WHO-100 and SF-36. The adaptability was assessed by application to 1356 community-based samples in Beijing. RESULTS: (1)Test-retest reliability of QOL-35: weighted Kappa indexes for items were from 0.86 to 1.00. Intraclass correlation coefficients were from 0.68 to 0.94 for domains, and 0.94 for total score. (2) On internal consistency: Cronbach's Alphas were 0.93, 0.97 and 0.89 for QO1-35, WHO-100 and SF-36. (3)On construct validity. The accumulated proportions of variances of the preceding seven factors were 66.5%, 50.3% and 65.3% for QOL-35, WHO-100 and SF-36. (4) On criterion validity. Spearman correlation coefficients of total QOL score of QOL-35 with those of WHO-100 and SF-36 were 0.805 and 0.745. (5)The rates of chronic diseases were 53.1%, 33.1%, 26.4% and 25.1% from first to fourth quantile of the total QOL scores of QOL-35(P<0.05). (6)Cronbach's Alpha was from 0.68 to 0.93 in 135 subjects, and from 0.71 to 0.91 in 1356 individuals of natural population. CONCLUSION: The QOL-35 instrument satisfied test-retest reliability and was highly correlated with WHO-100 and SF-36, having fewer items but better construction validity, better internal consistency, and better discrimination ability. We suggested that QOL-35 be used as a replicable tool to assess quality of life in the Chinese general population.

Adult↗

PubMed1991

The USC*PACK PC programs for population pharmacokinetic modeling, modeling of large kinetic/dynamic systems, and adaptive control of drug dosage regimens.

Programs for PC's and compatibles provide nonparametric (NPEM) population pharmacokinetic modeling, BOXES for compartments and arrows for pathways, to make large kinetic and dynamic models, and clinical software for Bayesian adaptive control of drug dosage regimens, with D-optimal sampling strategies and explicit determination of assay error patterns.

Bayes Theorem↗

PubMed1991

Quantitative determination of linoleic acid in infant formulas.

The aim of this paper is to develop a gas chromatographic method for the quantitative determination of linoleic acid in adapted, preterm, follow-up and special infant formulas. For sample preparation, lipids were extracted with a Soxhlet extractor after acid hydrolysis, and methyl esters of fatty acids were prepared in a sealed vial with hydrochloric acid in methyl alcohol and analysed using a packed polar column (SP 2330). Triheptadecanoin was chosen as internal standard. The method yielded reliable and repeatable results for all the examined formulas.

Chromatography, Gas↗

PubMed1990

Are nurse practitioners prepared for the AIDS epidemic?

Treatment of HIV-infected individuals will become a regular part of mainstream medical practice because of the increasing numbers of infected persons, the geographical dispersion of the disease, and the routine nature of much of the care required by seropositive patients. Nurse practitioners, like other health care professionals, need to be willing and able to provide such primary care. One hundred sixty-five NPs constituted an opportunity sample that was surveyed using an instrument that had been adapted from one used successfully in studies of other health professionals. The instrument consisted of 80 forced-answer and six open-ended questions. The response rate was 63 percent. It was found that nurse practitioners believed there was moderate risk of occupational contraction of HIV. NPs were more likely to agree on activities they believed to be of low risk than about the danger of perceived higher-risk activities. The respondents judged themselves as fairly competent in their ability to provide counseling and information to patients about HIV and risk-reduction. Half believed that their lack of knowledge was the biggest barrier to providing care to HIV-infected persons. Eighty-five percent thought courses on the medical aspects of AIDS were necessary, and 78 percent wanted courses in the social, ethical and legal implications of the disease. This study shows that there is a widely perceived need for continuing education on both medical and social aspects of AIDS in order to enable nurse practitioners to play a greater role in primary care provision for persons with AIDS.

Acquired Immunodeficiency Syndrome↗

PubMed1989

[Detection of visna-maedi virus antibodies and antigens by immunoblotting].

The visna-maedi virus was immunologically diagnosed using an immunoblotting technique from an antigenic preparation of the visna-maedi virus K796 purified by sucrose density gradient centrifugation. After SDS-PAGE electrophoresis and transfer onto a nitrocellulose sheet, the immunoblotting procedure was adapted to the search for specific antibodies in ovine serum samples. The results obtained showed that, in the natural visna-maedi disease, antibodies are not systematically detectable against every viral protein of the virus core. We have demonstrated the existence of antibodies directed against the proteins coded by the gag and the pol genes.

Animals↗

PubMed1979

Liquid-chromatographic determination of acetaminophen in serum.

We describe a sensitive and precise "high-pressure" liquid-chromatographic method for determining acetaminophen in serum. The 2-acetaminophenol and 3-acetaminophenol structural isomers of acetaminophen are used as internal standards. The method, which involves solvent extraction and adsorption chromatography on silica, provides excellent sensitivity, accuracy, and selectivity. The standard curve is linear over the range of acetaminophen concentrations of 0.5 to 300 mg/L, which makes the method useful for both pharmacokinetic studies and overdose monitoring. Analytical recovery is 97% for acetaminophen concentrations ranging from 5 to 300 mg/L. Many commonly used drugs were tested and found not to interfere. The procedure has been successfully adapted as a microscale method requiring only 50 microL of sample. The microscale method is particularly useful for pediatric and neonatal patients for whom sample size is a major concern.

Acetaminophen↗

PubMed1989

Levels of atmospheric pollution by man-made mineral fibres in buildings.

The widespread use of man-made mineral fibres (MMMF) as insulation products in buildings can be a potential source of indoor pollution, but few data are available. Pollution levels were determined at 79 indoor and 18 outdoor locations. The standardized method (membrane filter method) was adapted to the environmental settings: 10 m3 of air was sampled over a period of 5 days; the specimen was prepared by an indirect method (low-temperature ashing); counting was carried out at a magnification of 250; MMMF were identified by their optical properties under the polarizing optical microscope. Indoor pollution levels were found to be in the range 0-6230 respirable fibres per m3, with a median value of 3. Outdoor airborne pollution levels were lower than 15 respirable fibres per m3, with a median value of 1. More data are needed in order to make a more precise assessment of the risk associated with environmental MMMF pollution; a standardized method of obtaining such data is also necessary.

Air Pollutants↗

PubMed1988

Growth requirements for human acute lymphoblastic leukemia cells: refinement of a clonogenic assay.

Since freshly obtained acute lymphoblastic leukemia (ALL) cells rarely replicate spontaneously in vitro in a sustained way, development of a useful clonogenic assay for ALL blast progenitors is dependent on identifying the cellular growth requirements. Thus, marrows from 25 ALL cases were cultured in methylcellulose to determine the optimal conditions for cell growth. Blast colonies were confirmed as leukemic by morphology, cytochemistry, surface markers, and cytogenetics. Irradiated (7000 rads) normal peripheral blood feeder cells were an absolute requirement and produced number-dependent increases in ALL colonies; added growth factors enhanced the feeder cell effect. ALL cell-feeder cell contact was essential since their physical separation in a two-layer culture system drastically interfered with colony growth. Feeder cells from various donors, including new and relapsed cases of ALL, yielded colony numbers that differed widely when tested on the same marrow with and without added growth factor; thus, identification of a "good" feeder cell donor was key to an optimal assay. Neither recombinant interleukin-2 nor recombinant GM-CSF had ALL growth-promoting properties when tested alone or in combination but in the presence of feeder cells they moderately enhanced the feeder cell effect. The most effective growth factors were derived from cells exposed to phytohemagglutinin (PHA) for 72 h. In order of magnitude for colony growth-promoting activity, PHA-T cell conditioned medium (CM) was more stimulatory than PHA-blast cell CM followed by PHA-leukocyte CM; removal of PHA from CM by affinity chromotography did not alter the results. The most potent PHA-TCM was prepared from T-cells from a phlebotomized hemochromatosis patient; PHA-TCM from transfused thalassemia patients and normal donors were less active. Concanavalin-A blast cell CM had modest colony promoting properties whereas CM prepared with other B-cell mitogens and supernatants from ALL blasts in liquid culture had none. Our studies illustrate the complex and fastidious growth needs of ALL cells. The data have allowed us to refine a clonogenic blast progenitor assay that should facilitate study of proliferative properties of B and T lineage leukemias. The assay could be adapted further for detection of residual leukemia cells in marrow samples used for autologous transplantation, and in patients during complete hematological "remission."

Adolescent↗

PubMed1986

Epilepsy and prejudice: the dimensionality of stereotypes towards epileptics.

Previous investigations (cross-sectional and time series studies) to conditional structures of heterostereotypes toward epileptics are mainly based on the interview schedule of Caveness (1949). This item pool seems insufficient to parametrisize the horizon of attitudes toward epileptic persons. Antonak and Rankin (1981, 1982) found a higher degree of dimensionality of stereotypes by application of their ATPE scale (Attitudes toward persons with epilepsy). Therefore, studying the complex interaction of attitudes and knowledge about epileptics, we presented an adapted and translated German version of the ATPE to a sample of 372 volunteers. The dimensional decomposition of the 32 items resulted in five factors: 1. attitudes regarding education and social integration (EDUCINT), 2. attitudes regarding working behaviour (WORK), 3. negative attitudes regarding reproductive behaviour (REPR), 4. open discrimination (DISC), 5. passive tolerance (PASTOL). Variance analytical investigations showed a complex pattern of stereotypes in the sample in relation to sociodemographic background parameters.

Adolescent↗