Comparison of the effects of fan-assisted and natural ventilation of vehicles on the welfare of pigs being transported to slaughter.

A total of 417 pigs with an estimated average liveweight of 91 kg were transported to slaughter in three journeys, carried out in late June, each consisting of a three-hour drive followed by a one-hour holding period at the slaughter plant before they were unloaded. The pigs were accommodated on the lower two decks of a three-deck articulated lorry, each deck having five equal-sized pens; half were kept in naturally ventilated pens and half in pens with fan-assisted ventilation. The pigs' body temperature was recorded as the temperature of the blood lost at exsanguination, and as the temperature of the inner surface of the ear measured by thermal imaging. The pigs carried on the upper deck were hotter than those carried on the lower deck, and the pigs carried at the front of the vehicle were hotter than those at the back. There were small differences between the temperatures of the pigs in the different pens, but overall the temperatures of the pigs kept in pens with fan-assisted ventilation were no lower than those of the pigs kept in pens with natural ventilation. The higher temperature of the pigs transported in the front of the vehicle was associated with significantly higher serum concentrations of cortisol and activities of creatine kinase, and a tendency to higher albumin concentrations and osmolality, suggesting that they may have been exposed to more physical and psychological stress, and were possibly slightly more dehydrated, than the pigs in the rearmost pens. The type of ventilation had no effect on the blood composition of the pigs.

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.

Genomic organization of the gene coding for the costimulatory human B-lymphocyte antigen B7-2 (CD86).

The generation of an antigen-specific T-cell response requires that the T lymphocyte receive two signals from the antigen presenting cell. The specificity of this response is provided by antigen presented to the T lymphocyte and involves stimulation of the T lymphocyte via the T-cell receptor (TCR)/CD3 complex. The second, or costimulatory signal, can be provided by ligation of the B-lymphocyte activation antigens B7-1 (CD80) and B7.2 (CD86) to TCR antigen CD28. The cDNAs for both CD80 and CD86 have been isolated and are predicted to encode type 1 membrane proteins of the immunoglobulin (Ig) superfamily. The predicted protein is composed of a signal peptide followed by two Ig-like extracellular domains, a transmembrane domain, and a cytoplasmic tail. Here we report that the genomic organization of CD86 reflects its functional structure, and is similar to that found for CD80. The gene is composed of eight exons which span more than 22 kilobases. The predicted protein functional domains of signal peptide, extracellular IgV- and IgC-like regions, and transmembrane domain coincide with the genomic structure. Two independent sequences had been reported for CD86 cDNA which differed in their 5'untranslated (UT) regions. We find CD86 exons 1 and 2 correspond to these alternate 5'UT sequences. Splicing of exon 1 or 2 with the signal peptide encoding exon 3 would produce mRNA transcripts complementary to the reported cDNA clones. Exons 4 and 5 correspond to IgV- and IgC-like extracellular domains, respectively. Exon 6 encodes the transmembrane region and beginning of the cytoplasmic tail. Exons 7 and 8 encode the remainder of the cytoplasmic tail and 3'UT sequences.

Plasma boron and the effects of boron supplementation in males.

Recently, a proliferation of athletic supplements has been marketed touting boron as an ergogenic aid capable of increasing testosterone. The effect of boron supplementation was investigated in male bodybuilders. Ten male bodybuilders (aged 20 to 26) were given a 2.5-mg boron supplement, while nine male bodybuilders (aged 21 to 27) were given a placebo for 7 weeks. Plasma total and free testosterone, plasma boron, lean body mass, and strength measurements were determined on day 1 and day 49 of the study. A microwave digestion procedure followed by inductively coupled argon plasma spectroscopy was used for boron determination. Twelve subjects had boron values at or above the detection limit with median value of 25 ng/ml (16 ng/ml lower quartile and 33 ng/ml upper quartile). Of the ten subjects receiving boron supplements, six had an increase in their plasma boron. Analysis of variance indicated no significant effect of boron supplementation on any of the other dependent variables. Both groups demonstrated significant increases in total testosterone (p < 0.01), lean body mass (p < 0.01), and one repetition maximum (RM) squat (p < 0.001) and one RM bench press (p < 0.01). The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser-trained bodybuilders, but boron supplementation affects these variables not at all.

Zinc loss in sweat of athletes exercising in hot and neutral temperatures.

Zinc (Zn) loss from sweat of 9 male and 9 female athletes exercising under hot (35 degrees C, HE) and neutral (25 degrees C, NE) conditions was examined. Subjects exercised at 50% VO2max on a cycle ergometer for 1 hr during each trial. Cell-free sweat samples were analyzed for Zn by atomic absorption spectrophotometry. There was a significant interaction of time, gender, and temperature for whole-body sweat rates (WBSR). WBSR for males were higher during both trials and at each time. WBSR from the second half of exercise were higher than those from the first half for both sexes and temperature conditions. Sweat Zn concentration was higher in the NE than in the HE, but when the sweat rates were included, the rate of Zn loss was no different between HE and NE. Zn concentration of the sweat for the first half of exercise was over twice that of the second half. Sweat Zn concentration of the men was no different than that of the women; however, due to greater sweat rate, men had significantly higher Zn losses. Although total Zn losses are estimated to be relatively low compared to the RDA, exercise at moderate intensities may increase surface Zn losses.

Undernutrition and vitamin A deficiency in the Department of Linguère, Louga Region of Sénégal.

Anthropometric measurements were taken on 281 toddlers (24-48 mo old) in Linguère, Sénégal, to determine the prevalence of undernutrition. Blood samples collected from 271 of the toddlers were analyzed for retinol and carotenoids by HPLC. According to the National Center for Health Statistics reference values 30.2% of the population was undernourished. Serum retinol values were below the lower limit of the normal range in 71.5% of the children; 7.4% of this group had concentrations < 0.35 mumol/L, placing them at risk for xerophthalmia. Only 3% of the population had serum retinol values > or = 1.0 mumol/L. Serum carotenoids were low (< 0.70 mumol/L) in 55% of the children. Retinol-binding protein values were low and measurable concentrations of retinyl palmitate were detectable in only 17% of the children. Undernutrition and poor vitamin A status were found to exist at a concentration that would endanger health.

The effect of boron supplementation on lean body mass, plasma testosterone levels, and strength in male bodybuilders.

The effect of boron supplementation was investigated in 19 male bodybuilders ages 20-27 years. Ten were given a 2.5-mg boron supplement while 9 were given a placebo every day for 7 weeks. Plasma total and free testosterone, plasma boron, lean body mass, and strength measurements were determined on Days 1 and 49 of the study. Plasma boron values were significantly (p < 0.05) different as the experimental group increased from (+/- SD) 20.1 +/- 7.7 ppb pretest to 32.6 +/- 27.6 ppb posttest, while the control group mean decreased from 15.1 +/- 14.4 ppb pretest to 6.3 +/- 5.5 ppb posttest. Analysis of variance indicated no significant effect of boron supplementation on any of the dependent variables. Both groups demonstrated significant increases in total testosterone, lean body mass, 1-RM squat, and 1-RM bench press. The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser trained bodybuilders, and that boron supplementation had no effect on these measures.

Microwave digestion preparation and ICP determination of boron in human plasma.

A microwave digestion procedure, followed by Inductively Coupled Argon Plasma Spectroscopy, is described for the determination of boron (B) in human plasma. The National Institute of Standards and Technology (NIST) currently does not certify the concentration of B in any substance. The NIST citrus leaves 1572 (CL) Standard Reference Material (SRM) and wheat flour 1567a (WF) were chosen to determine the efficacy of digestion. CL and WF values compare favorably to those obtained from an open-vessel, wet digestion followed by ICP, and by neutron activation and mass spectrometric measurements. Plasma samples were oxidized by doubled-distilled ultrapure HNO3 in 120 mL PFA Teflon vessels. An MDS-81D microwave digestion procedure allows for rapid and relatively precise determination of B in human plasma, while limiting handling hazards and sources of contamination.

Dietary intake and blood lipid profile survey of fighter pilots at Tyndall Air Force Base.

A 24-hour dietary recall, a food frequency checklist, and a blood lipid profile were collected from 30 USAF fighter pilots. Sample mean intakes of nutrients studied met U.S. military recommended dietary allowances, except for folic acid, which was 78%. Mean percentages of energy derived from carbohydrate, protein and fat were 48.3, 16.1 and 34.2%, respectively. Of the pilot sample, 63% reported they did not eat breakfast daily. Sample mean blood lipid profile values were: total cholesterol = 218 mg/dl, HDL-cholesterol = 45 mg/dl, triglycerides = 109 mg/dl. Based on total cholesterol level, 40% of the pilot sample should have follow-up according to the National Cholesterol Education Program. A significant negative relationship was found between reported exercise frequency and total cholesterol/HDL-cholesterol ratio. Some fighter pilots could benefit from counseling with a dietitian regarding dietary intake patterns, decreasing dietary fats, and the advantages of regular exercise.

Acute effects of resistance exercise on parameters of lipoprotein metabolism.

Ten healthy, trained males (25.4 +/- 3.1 yr) were studied before and after 90 min of resistance exercise to determine the acute effects of high volume (HV) and low volume (LV) sessions on alterations in lipid and lipoprotein concentrations as well as the activity of lecithin: cholesterol acyltransferase (LCAT). The HV session involved the use of 8-12 repetition maximum (RM) loads performed to exhaustion with 60 s rest intervals between sets, while the LV session involved the use of 1-5RM loads with 3 min rest intervals between sets. Fasting blood samples were drawn from an antecubital vein immediately before and after exercise as well as 24, 48, and 72 h post-exercise. Following adjustment for changes in plasma volume, significant changes were only found following the HV session. These included increases in HDL-C (11%) and HDL3-C (12%) 24 h post-exercise. Modifications in HDL-C were significantly different from both the LV and control sessions. In contrast, triglycerides and LCAT were significantly depressed 24 h post-exercise following the HV session when compared with immediate post-exercise values. There were no significant changes in either total cholesterol or HDL2-C at any time. The results of this study suggest that the potential of resistance exercise to affect acute modifications in the lipoprotein profile resides in the volume of exercise performed.

Diagnosis of human ehrlichiosis with the indirect fluorescent antibody test: kinetics and specificity.

Human ehrlichiosis, an acute febrile illness caused by Ehrlichia canis or a closely related rickettsial organism, was first identified in 1986. From 1986 through 1988, sera from 85 patients demonstrated a fourfold rise or fall in antibody titer to E. canis. Seven (22%) of 32 patients initially tested during the first week after onset of illness. 17 (68%) of 25 tested during the second week, and all 18 tested during the third week had titers that exceeded the minimum positive titer of greater than or equal to 80. Of the 85 confirmed ehrlichiosis patients, 31 (36.5%) also had indirect fluorescent antibody titers considered diagnostic of infection with Rickettsia rickettsii, Rickettsia typhi, or Coxiella burnetti, but in most these diagnoses were not supported by epidemiologic, clinical, or serologic evidence. These results emphasize that patients suspected of having a tick-borne infection should be tested for antibodies to E. canis as well as for those to other rickettsiae.

Molecular cloning and chromosome mapping of the human gene encoding protein phosphotyrosyl phosphatase 1B.

The inactivation of growth suppressor genes appears to play a major role in the malignant process. To assess whether protein phosphotyrosyl phosphatases (protein-tyrosine-phosphate phosphohydrolase, EC 3.1.3.48) function as growth suppressors, we have isolated a cDNA clone encoding human protein phosphotyrosyl phosphatase 1B for structural and functional characterization. The translation product deduced from the 1305-nucleotide open reading frame predicts a protein containing 435 amino acids and having a molecular mass of 49,966 Da. The amino-terminal 321 amino acids deduced from the cDNA sequence are identical to the empirically determined sequence of protein phosphotyrosyl phosphatase 1B. [Charbonneau, H., Tonks, N. K., Kumar, S., Diltz, C. D., Harrylock, M., Cool, D. E., Krebs, E. G., Fischer, E. H. & Walsh, K. A. (1989) Proc. Natl. Acad. Sci. USA 86, 5252-5256]. A genomic clone has been isolated and used in an in situ hybridization to banded metaphase chromosomes to determine that the gene encoding protein phosphotyrosyl phosphatase 1B maps as a single-copy gene to the long arm of chromosome 20 in the region q13.1-q13.2.

Effects of dietary fats and butylated hydroxytoluene on mutagen activation in rats.

The effects of hydrogenated fats and butylated hydroxytoluene (BHT) in the diets of rats on the hepatic activation of benzo(a)pyrene, 2-acetylaminofluorene (AAF), and 2-aminofluorene by liver homogenates (S-9 fraction) were evaluated. The Salmonella/microsomal mutagenicity assay (Strain TA 98) was utilized to determine the mutagenic potential of the activated compounds. The S-9 fraction was obtained from animals fed a 15% fat diet consisting of hydrogenated fats (43% trans-fatty acids) or unsaturated fats (0% trans-fatty acids). BHT was administered orally (0.5%) 6 days prior to sacrifice in both groups. The incorporation of BHT in the diet of rats enhanced the mutagenic potential of AAF and 2-aminofluorene but not of benzo(a)pyrene. This effect was independent of the lipid composition of the diet. The most significant increment in the production of mutagenic metabolites was observed with AAF when BHT and hydrogenated fats were included in the diet of rats. Dietary hydrogenated fats appeared to potentiate the effects of BHT on AAF mutagenicity. Further studies to elucidate the mechanisms by which BHT and hydrogenated fats enhance AAF mutagenicity are warranted.

Screening of safrole, eugenol, their ninhydrin positive metabolites and selected secondary amines for potential mutagenicity.

The mutagenicity of safrole, eugenol, the secondary amines, with which they combine during metabolism, and the ninhydrin positive urinary metabolites of safrole and eugenol was tested. The panel of tests included the direct bacterial assay, a microsomal mutagenesis assay and a host-mediated assay. With the direct bacterial assay employing four mutant strains of Salmonella typhimurium (TA1530, TA1531, TA1532, TA1964), all the compounds gave negative results. In the microsomal mutagenesis assay, employing the same four mutant strains, safrole and safrole metabolite II were mutagenic with strains TA1530 and TA1532. Dimethylamine was also found to be a weak mutagen in the microsomal mutagenesis assay with strain TA1530. Safrole and safrole metabolite II were also mutagenic in the host-mediated assay with strains TA1950 and TA1952. Negative results were observed for safrole metabolites I and III, eugenol, eugenol metabolites I and II, piperidine, pipecolic acid, proline, and pyrrolidine in all three assay systems.