Effects of animal and soy fats and proteins in the diet on fatty acid concentrations in the serum and skin of dogs

Growing dogs were fed diets containing soy oil or poultry fat as the main fat source and soybean meal or meat meal as the main protein source to examine the effects of types of dietary fat and protein on fatty acid concentrations in serum and skin and on serum cholesterol concentrations. Dogs fed diets containing soy oil had higher serum linoleic acid concentrations and lower serum oleic acid, arachidonic acid, and cholesterol concentrations than dogs fed diets containing poultry fat. The type of dietary protein had marginal effects on fatty acid concentrations and did not affect serum cholesterol. Similar differences were found in cutaneous fatty acid concentrations, with soy oil-fed dogs having significantly (P < 0.05) higher linoleic acid and lower oleic acid concentrations in their skin than had poultry fat-fed dogs. This study suggested that dietary fat source influences serum and cutaneous fatty acid concentrations and serum cholesterol concentrations in dogs, irrespective of dietary protein source.

Traffic accident involvement rates by driver age and gender

Passenger-vehicle travel data from the 1990 Nationwide Personal Transportation Survey were combined with crash data from the 1990 Fatal Accident Reporting System and the 1990 General Estimates System to produce crash involvement rates per vehicle-mile of travel. Elevated rates were observed for drivers aged 16-19 and 75 and over. The oldest drivers had the highest fatal involvement rate, while the youngest drivers had the highest rate of involvement in all police-reported crashes. Men had a higher risk than women of experiencing a fatal crash, while women had higher rates of involvement in injury crashes and all police-reported crashes.

The peroxisomal membrane proteins of Candida boidinii: gene isolation and expression

Candida boidinii is a methylotrophic yeast in which several growth substrates can cause vigorous peroxisomal proliferation. While such diverse substrates as methanol, oleic acid and D-alanine induce different peroxisomal metabolic pathways, membranes seem to contain common abundant peroxisomal membrane proteins (PMPs). These proteins have been termed PMP31, PMP32 and PMP47. The gene encoding PMP47 has been previously cloned and analysed. We now report the isolation of a second PMP47 gene (or allele) as well as PMP31 and PMP32. PMP47A and PMP47B share 95% sequence identity at the amino acid level. PMP31 and PMP32 each contain 256 amino acids and are highly similar (97% identity) in protein sequence. Both PMP31 and PMP32 are predicted to span the membrane once or twice. All abundant PMPs of C. boidinii are basic in charge; they all have predicted isoelectric points above 10. RNAs corresponding to the PMP47s and to PMPs31-32 are strongly induced by methanol, oleic acid and D-alanine. While the PMP47s probably encode substrate carriers, the functions of PMP31 and PMP32 from C. boidinii are still unknown.

Heat increment of feeding and its thermoregulatory benefit in the muskrat (Ondatra zibethicus)

The calorigenic effect of feeding and its potential benefit in defraying thermoregulatory costs and attenuating immersion hypothermia of adult muskrats were investigated. A single session of feeding on aquatic vegetation was sufficient to raise the metabolic rate of muskrats for a period of at least 5 h. The peak postprandial rate of oxygen consumption averaged 1.42 times the level established for fasted animals, and the heat increment of feeding accounted for about 40% of the metabolizable energy intake of muskrats. There was no evidence of a postprandial rise in oxygen consumption of muskrats that entered water at 18-19 degrees C after feeding. In aquatic trials, average and minimum steady-state oxygen consumption rates of fed muskrats were similar to, or even lower than values recorded from fasted animals, implying substitution of heat increment of feeding for thermoregulatory heat production. Our data did not support the hypothesis that heat increment of feeding retards body cooling in water. Net body temperature decline in water was actually higher in fed animals than in fasted controls. However, since previously fed muskrats also entered water at an elevated body temperature, the final body temperature (at 30 min immersion) was similar in all groups. These findings suggest that metabolic heat generated incidental to preimmersion feeding could provide a thermoregulatory benefit to muskrats by reducing the need for active thermogenesis in water.

Endotoxin-exposed atria exhibit G protein-based deficits in inotropic regulation

BACKGROUND

Diminished response at the myocardial beta 1-adrenoceptor is established in endotoxemia. The myocardial muscarinic-2 acetylcholine receptor (M2ACHR) has not been investigated in endotoxemia, although it shares a G protein-mediated link to adenyl cyclase (AC). This study aimed to assess the contractile responses elicited at the M2ACH and beta 1 receptors, their respective G proteins, and the AC unit in endotoxemia.

METHODS

Isometric force and rate of contraction were measured in atria from Sprague-Dawley rats after exposure to 24-hour continuous intravenous infusion of 0.2 mg/kg endotoxin or vehicle. The responses to isoproterenol, acetylcholine, sodium fluoride (NaF), and forskolin were studied.

RESULTS

In a comparison of endotoxic versus control atria, diminished force response at the beta 1-adrenoceptor was confirmed (4.98 +/- 1.343 vs 7.26 +/- 1.568 gx10 [gx10 is unit of measure used for force], p = 0.0006, n = 10), and an analogous defect at the M2ACHR was identified (6.66 +/- 0.906 vs 8.16 +/- 1.307 gx10, p = 0.009, n = 10). NaF was able to directly activate Gs and G(i) in a dose-dependent differential manner. Both Gs (5.40 +/- 0.795 vs 7.81 +/- 1.057 gx10, p = 0.0015, n = 6) and G(i) (2.73 +/- 0.528 vs 3.76 +/- 0.332 gx10, p = 0.003) force responses were diminished in endotoxic atria. Stimulus of AC by forskolin yielded similar force increases (3.15 +/- 0.731 vs 3.21 +/- 0.667 gx10, p = 0.89, n = 9).

CONCLUSIONS

In this model only contractile responses were altered by endotoxemia. The use of NaF revealed dysfunction distal to agonist receptor interaction and with the data from M2ACHR activation confirmed that this defect is not adrenergic specific. The preserved response at AC localized the site of this myocardial receptor dysfunction to the G proteins.

Effect of trimethoprim/sulfamethoxazole on thyroid function in dogs with pyoderma

The effect of trimethoprim/sulfamethoxazole (T/SMX, 30 mg/kg, PO, q 12 h for 6 weeks) on thyroid function was evaluated in 21 dogs with pyoderma and normal baseline serum thyroxine concentrations. The population mean serum thyroxine concentration, but not the population mean serum triiodothyronine concentration, was significantly decreased at the end of treatment. After 6 weeks of treatment, the response in 3 dogs to thyrotropin administration was substantially reduced. Radionuclide thyroid imaging of 2 dogs after T/SMX treatment revealed higher-than-normal thyroid technetium 99m pertechnetate uptake, suggestive of an interference with iodide metabolism. Use of T/SMX may cause hypothyroidism, and inadequate thyroid function may be incorrectly diagnosed in dogs treated with this antimicrobial.

Development of a collision typology for evaluation of collision avoidance strategies

This paper summarizes the results of an effort to identify and rank vehicle collision scenarios in order to create a "collision typology" that could aid in the assessment of the potential benefit of accident avoidance technologies. Data from four computerized accident files were used to construct an 18-level collision configuration variable. This variable includes the number of vehicles involved, their relative orientation, intent to turn, relation to intersection, and traffic control at the intersection. Distributions of the collision configuration variable were generated for several factors of interest using 1989 Michigan data. Five of the most prevalent collision types were selected for more detailed review based on the original police accident reports. The case studies lent additional insight into the circumstances of different accident types. Among other findings, the review suggested that in collisions at nonsignalized intersections, older drivers often stopped and then pulled out into oncoming traffic, while younger drivers more often failed to stop at all.

Accident rates for heavy truck-tractors in Michigan

Accident rates of heavy truck-tractors are modelled using log-linear methods. The accident data used are a census of truck-tractor involvements in Michigan from May 1987 to April 1988. Travel data used to calculate the rates were produced by a survey of truck-tractors in Michigan covering the same time period. Both the accident and travel data were limited to Michigan-registered tractors operating in Michigan. Log-linear models of casualty and property-damage-only accident rates were developed using number of trailers, road type, area type, and time of day as predictor variables. Overall, differences between tractors with one and two trailers were not significant. Tractors with no trailers (bobtails) have significantly higher accident rates. Characteristics of the operating environment were found to have larger effects on the accident rate than tractor configuration (except for the bobtail). Rates varied by a factor of up to 6.8, depending on the road type. Casualty accident risk at night was 1.4 times the risk during the day. The risk of a casualty accident in rural areas was 1.6 times that of urban areas.

Pregnancy loss in Nomadic and settled women in Turkana, Kenya: a prospective study

There have been few investigations of intrauterine mortality in non-Western populations that have used techniques capable of detecting early pregnancy loss. We report here the initial results of a prospective study of fetal loss among the Turkana of northwest Kenya. Over 300 nomadic and settled women provided early morning urine samples for 3 consecutive days. Chorionic gonadotropin (hCG), a marker for pregnancy, and markers of ovarian cyclicity (LH, PdG) were determined with solid-phase enzyme immunoassays. Pregnancy was detected in 11% of nomadic women and in 22% of sedentary women of reproductive age. Follow-up surveys revealed that 45% of all pregnancies among settled women were lost; nearly 70% of pregnancies detected in the first trimester were lost. In contrast, none of the nomadic women experienced fetal loss. Because of the small sample sizes, these results must be interpreted cautiously. Nevertheless, even a conservative estimate of the fetal loss rate among the settled women is high compared with Western experience. Anthropometric data suggest that nutritional stress may contribute to the difference between the two populations. There is also some indication that risk of fetal loss in the settled population is associated with parity. The high rate of loss among the settled women along with the difference between the nomadic and settled samples supports the contentions that there may be substantial variation among populations in intrauterine mortality and that the contribution of fetal loss to fertility differences among populations may be more important than has been suspected.

Effects of oral sunflower oil and olive oil on serum and cutaneous fatty acid concentrations in dogs

The effects of dietary fatty acids on serum and cutaneous fatty acids of healthy dogs were evaluated under controlled conditions. Beagle puppies (n = 12) were fed a standard diet supplemented with sunflower oil (group A), olive oil (group B) or no supplementation (group C) for 12 weeks. There were no significant differences in food intake or growth rates between the three groups. Dogs in group A had significant increases (P < 0.05) in serum 18:2n6 (linoleic acid) and 20:3n6 (dihomo-gamma-linolenic acid), and cutaneous 18:2n6 with significant decreases in serum 20:4n6 (arachidonic acid) and cutaneous 18:1n9 (oleic acid) and 18:3n3 (alpha-linolenic acid). Dogs in group B had significant increases in serum 18:1n9, 20:3n6 and cutaneous 18:1n9 with decreases in serum 20:4n6, 22:4n6, 22:5n3 and 22:5n6, and cutaneous 18:2n6, 18:3n3 and 20:4n6. There were no significant changes in serum or cutaneous fatty acids for the dogs in group C. This study demonstrates that fatty acid supplements can be used to alter the serum and cutaneous fatty acid compositions of dogs.

Non-steroidal anti-inflammatory drugs and appendicitis in patients aged over 50 years

In a retrospective study 84 patients aged > or = 50 years undergoing emergency appendicectomy were matched for age and sex with 84 randomly selected emergency admissions as controls. Of the former, 31 (37 per cent) were taking non-steroidal anti-inflammatory drugs. (NSAIDs) at admission, compared with nine (11 per cent) of the controls (P < 0.01). In the study group a suppression of the white cell count was identified on admission in those taking NSAIDs (mean 11.9 x 10(9) l-1) compared with those not (mean 14.8 x 10(9) l-1) (P = 0.007). This is the first reported association between appendicitis and NSAIDs. The relative risk by odds ratio was substantially increased at 6.5 (95 per cent confidence interval 2.1-8.8). An NSAID-related impairment of host defences leading to failure in the resolution of inflammatory episodes may explain this association. It is further postulated that the suppression of the white cell response may be a marker of such an effect.

Fatty acid supplementation and skin disease

The importance of dietary fatty acids to the health of the skin was recognized more than 60 years ago. Fatty acids are important in providing membrane fluidity and maintaining the cutaneous water permeability barrier. Fatty acids function as precursors of eicosanoids. Eicosanoids, which include prostaglandins and leukotrienes, influence cellular interactions, cellular proliferation, and inflammation. Certain diseases, such as atopy and hypothyroidism, are characterized by abnormalities in fatty acid metabolism. Dietary manipulations may be useful in the treatment of diseases mediated by eicosanoids.

Effects of thyroid hormones on serum and cutaneous fatty acid concentrations in dogs

The effects of thyroid hormones on the serum and cutaneous fatty acid concentration profiles of dogs were evaluated. Thyroidectomized dogs had significant (P less than 0.05) increases in serum oleic acid and linoleic acid concentrations, and decreases in concentration of dihomo-gamma-linolenic acid, arachidonic acid, and other elongation products of fatty acid metabolism. These changes were reversed in response to thyroid hormone replacement. Similar changes were found in cutaneous fatty acid concentration profiles. Thus, in dogs, thyroid hormones may be involved in the regulation of fatty acid delta-6-desaturase activity.

Cutaneous inverted papillomas in dogs

Inverted papillomas of the skin occurred in five dogs. Lesions were 1-2 cm, circumscribed, flask-like structures below the level of the surrounding normal skin. Walls of the structures consisted of hyperplastic epidermis, forming thin papillary projections on thin fibrovascular stalks. Cells in the stratum granulosum had clear cytoplasm, numerous keratohyalin-like granules of various sizes, and poorly defined intranuclear inclusions. These cells stained positively for papillomavirus group-specific antigens by both the peroxidase-antiperoxidase and avidin-biotin methods. Virions with a mean diameter of 35.7 nm were present within nuclei in cells of the stratum granulosum when examined by electron microscopy. In situ DNA hybridization, using a canine oral papillomavirus probe, localized papillomavirus DNA in canine oral papillomas, but not in canine cutaneous squamous or inverted papillomas, suggesting that a different papillomavirus type was present in the latter lesions. Although these lesions resembled intracutaneous cornifying epitheliomas (keratoacanthomas), they appear to be a distinct lesion, probably with a different etiology.

Cholelithiasis in a cat

A 4-year-old cat was examined because of anorexia and lethargy. The cat became icteric within 3 days of admission. Values for aspartate transaminase, alanine transaminase, total bilirubin, alkaline phosphatase, and cholesterol were higher than normal. Radiography revealed hepatomegaly, with loss of detail in the cranioventral portion of the abdomen. Further diagnostic procedures were not permitted, and the cat was euthanatized. At necropsy, cholecystitis, cholangitis, and numerous choleliths were found. Cholelithiasis is a rare cause of obstructive jaundice in the cat.