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T K Smith

Publications and source records attributed to T K Smith.

At least 163 records · Page 9Linked to original sources
PubMed1982

Dietary influences on excretory pathways and tissue residues of zearalenone and zearalenols in the rat.

Experiments were conducted with male weanling rats to determine the effect of high dietary protein (40% casein), alfalfa (25%), protein + alfalfa (25% casein + 25% alfalfa), or anion-exchange resin (5%) on the relative proportions of free and conjugated zearalenone and zearalenols excreted in urine and feces following a single oral dose of zearalenone. About 90% of the dose was excreted in feces after 48 h while the remaining 10% was excreted in urine. Zearalenone and metabolites were excreted mainly in free form with conjugates being found only in urine. Rats fed high-protein diets excreted more free zearalenone and alpha-zearalenol in urine than did controls (16.3% casein). The feeding of protein + alfalfa also resulted in increased urinary losses of free zearalenone. A reduction in urinary losses of conjugated zearalenone and alpha-zearalenol was seen when 5% anion-exchange resin was fed. Fecal excretion of zearalenone and alpha- and beta-zearalenol increased when alfalfa + protein was fed. Residual zearalenone and zearalenols were measured in liver and kidney 18 h after dosing. All treatments except high protein reduced residues of zearalenone and alpha-zearalenol in liver when compared with controls. Renal residues of zearalenone were lowered only by supplements of protein + alfalfa or anion-exchange resin. Each of the treatments fed has been shown to reduce zearalenone toxicosis in rats, but it was concluded that each does so by a different mechanism.

Animals↗
PubMed1982

Effect of dietary alfalfa on zearalenone toxicity and metabolism in rats and swine.

Experiments were conducted with rats and swine to determine the potential of dietary alfalfa as a treatment for zearalenone (Z) toxicosis. Ninety-six female weanling Wistar rats were fed a casein-based semipurified diet containing 0, 15 or 25% alfalfa and 0 or 250 micrograms Z/g feed. Exposure to Z for 14 d resulted in reduced growth, feed consumption and feed efficiency as well as kidney and liver enlargement and reduced activity of 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD). Z had no effect on uterine weight. Including alfalfa in these diets reduced the inhibitory effects of Z on growth and feed consumption, minimized Z-induced liver enlargement and increased hepatic 3 alpha-HSD activity. Dietary alfalfa also reduced concentrations of residual Z and zearalenols (Zl) in liver. In a second experiment, 108 Yorkshire gilts weighing 8 to 11 kg were fed diets containing 0, 15 or 25% alfalfa and 0, 10, 20 or 40 micrograms Z/g feed for 4 wk. Z caused uterine enlargement when fed as low as 10 micrograms/g feed, although no effects were seen in growth rate, feed consumption or feed efficiency. Alfalfa decreased uterine enlargement (P less than .05), but caused a depression in feed efficiency (P less than .05). Hepatic 3 alpha-HSD activity was five times lower in swine than in rats, although activity still tended to decrease with Z and increase with alfalfa feeding. Residues of Z and Zl in pig liver indicated species differences in the metabolism of Z. These studies show that dietary alfalfa promotes Z metabolism in rats and that this feedstuff may also be useful for treating Z toxicosis in livestock.

3-Hydroxysteroid Dehydrogenases↗
PubMed1982

Influence of mycotoxins on protein and amino acid utilization.

The interrelationships between mycotoxins and the utilization of dietary protein are reviewed. Acute aflatoxicosis is characterized by reduced growth and fatty infiltration of the liver. Studies with poultry, swine, and monkeys have shown that supplements of dietary protein beyond normal requirements can overcome these conditions. High-protein diets, however, have been shown to promote hepatoma characteristic of chronic aflatoxicosis in rats. Aflatoxin interferes with utilization of dietary protein by inhibiting synthesis of DNA, RNA, and protein. High-protein diets promote the metabolism of aflatoxin by the hepatic microsomal drug-metabolizing enzyme system. The Fusarium mycotoxin zearalenone increases membrane permeability and promotes uterine synthesis of DNA, RNA, and protein. Supplements of dietary protein overcome growth reduction due to zearalenone and reduce the metabolic half-life of the toxin by promoting urinary excretion of free, unmetabolized zearalenone in the rat. The trichothecene mycotoxins disrupt normal protein metabolism by inactivating the ribosomal cycle. Protein supplements appear to have little effect on trichothecene mycotoxicoses. Most mycotoxins impair utilization of dietary protein. The effectiveness of protein supplements in overcoming mycotoxicoses will depend on the mycotoxin in question.

Aflatoxins↗
PubMed1982

High pressure liquid chromatography of zearalenone and zearalenols in rat urine and liver.

A high pressure liquid chromatographic technique with internal standardization has been developed for determining zearalenone and metabolites in rat urine and liver. Following extraction with methylene chloride and solvent partition, samples are cleaned up by applying the extract to a Sephadex LH-20 column and eluting with a mixture of benzene-methanol (85 + 15). Compounds were resolved on 2 Part-isil-10 columns (25 cm x 4.6 mm id) in series with a mobile phase of isooctane-chloroform-methanol (35 + 25 + 3), and detected at 280 nm. The internal standard was 6'alpha-acetoxyzearalane. Limits of detection were about 2.0 ng for zearalenone and 5.0 ng for zearalenols (6'-hydroxyzearalane). Zearalenone and zearalenols were excreted mainly in free form with relatively little glucuronide conjugation. Metabolism of zearalenone to free zearalenol was minor compared with formation of bound forms.

Animals↗
PubMed1982

Nutrition in orthopaedic surgery.

One hundred and twenty-nine patients undergoing orthopaedic surgical procedures were found to have an average incidence of clinical and subclinical malnutrition of 42.4 per cent per patient. The lowest incidence of nutritional depletion was identified in patients undergoing total hip-replacement surgery (28.6 per cent), followed by the elective surgical group (35.3 per cent) and patients with multiple trauma and femoral fractures (58.6 per cent). Trauma and major surgery were shown to induce a state of malnutrition and a loss of immunocompetence. A significant (p less than 0.05) correlation between subnormal nutritional indices and the development of complications was identified. A comprehensive approach to the detection and correction of malnutrition in orthopaedic patients is described.

Adolescent↗
PubMed1981

The Frank Stinchfield Award Paper. Nutritional assessment of orthopaedic patients undergoing total hip replacement surgery.

This study confirms recent reports from other disciplines that show a high incidence of nutritional depletion among hospitalized patients. Preoperative assessments revealed a 50% incidence of subclinical nutritional depletion. Nutritional assessment is of value in the diagnosis, treatment, and continuing evaluation of the orthopaedic patient. Clearly the incidence and consequences of malnutrition in orthopaedic patients deserve further evaluation. Appropriate nutritional support needs to be more widely disseminated to and evaluated in this population. Whereas it is doubtful that sterile technique and operative procedures will be greatly improved in the foreseeable future, supportive nutrition therapy may offer the best prospect for immediate and substantial improvement in patient care.

Adult↗
PubMed1980

Effect of dietary protein, alfalfa, and zeolite on excretory patterns of 5',5',7',7'-[3H]zearalenone in rats.

A series of experiments was conducted to determine how dietary protein, alfalfa, or zeolite influence the excretory patterns of zearalenone (Z), a uterotropic mycotoxin synthesized by Fusarium fungi. Rats were fed diets containing 16.3% casein, 40% casein, 11.2% casein + 25% alfalfa, or 25% casein + 25% alfalfa. Also fed were diets containing 0, 1, 2, or 5% anion exchange zeolite. Tracer doses of [3H]Z were administered either as a constituent of the diet or as a topical application on the skin at the base of the skull. When Z was administered orally, no differences were seen in the fraction of the dose excreted in urine or feces as a result of varying dietary levels of alfalfa and protein. Topical doses resulted in rats fed 25% casein + 25% alfalfa or 40% casein excreting more Z in urine than those fed 25% alfalfa or 16.3% casein. Fecal excretion of Z was greatest for rats fed 25% casein + 25% alfalfa whereas rats fed 40% casein excreted more fecal Z than those fed 16.3% casein. Feeding Z to rats receiving dietary zeolite resulted in a positive correlation between dietary zeolite and fecal excretion of Z but a negative correlation with urinary excretion of Z. Topical administration of Z produced a positive correlation between dietary zeolite and fecal Z excretion but no effect on urinary excretion. It may be concluded that protein and alfalfa treatments alleviate Z toxicosis through increased metabolism whereas zeolite binds Z in the digestive tract to prevent absorption.

Aluminum Silicates↗
PubMed1979

Experience with the McAtee olecranon device in olecranon fractures.

Treatment of olecranon fractures by prolonged immobilization often results in limited elbow motion. With the use of a compression screw apparatus, anatomical reduction was obtainable, and only a short period of immobilization was needed. In a series of eleven fractures there were no non-unions and an average decrease in elbow range of motion of only 8 degrees.

Adult↗
PubMed1978

The branched-chain amino acid antagonism in chicks.

The effects of dietary supplements of branched-chain amino acids on growth, food consumption and metabolism in chicks were investigated. When an adequate diet contained 1.20, 1.60, 2.25, 3.75, or 5.00% leucine, increasing leucine content caused reduced food consumption and weight gains, coupled with impaired efficiency of food utilization. When the diet deficient in branched-chain amino acids contained 0.98, 1.46, 2.25, 3.75, or 5.00% leucine, increasing leucine resulted in increased food consumption and reduced efficiency of food utilization when levels of leucine up to 3.75% were fed. Excess leucine depressed plasma concentrations of isoleucine and valine. Excesses of isoleucine or valine caused smaller depressions of concentrations of the other two branched-chain amino acids. All these effects were seen during the first 8 days of experiment, after which they diminished or disappeared. Muscle branched-chain amino acid aminotransferase (BCAT) (L-leucine:2-oxoglutarate aminotransferase, EC 2.6.1.6) activity was increased in chicks fed excess leucine but not in those fed excess isoleucine or valine. Hepatic alpha-ketoisocaproic dehydrogenase (KADH) (2-oxoisocaproate:lipoate oxidoreductase, EC 1.2.4.3) activity and muscle polyribosomal aggregation were unaffected by diet. When chicks were fed diets containing either 0.98 or 2.25% leucine, production of 14CO2 from [1-14C]isoleucine and [1-14C]valine was increased in chicks fed the higher level of leucine. The increase was small in both cases, representing approximately 2% of consumed isoleucine and valine. Increased production of 14CO2 was observed within 12 hours of feeding excess leucine; however, BCAT increased only after 2 to 4 days. No differences were seen in excreted 14C or in the relative distribution of 14C along the small intestine. We conclude that the chick is able to adapt in part to excesses of dietary leucine and that the branched-chain amino acid antagonism may involve increased catabolism of the limiting branched-chain amino acids.

Animals↗
PubMed1978

Prune-bell syndrome: a report of twelve cases and review of the literature.

Prune-belly syndrome is a rare congenital disease involving a deficiency of abdominal muscles, genitourinary abnormalities, and cryptorchidism. About half of the patients with the disease have associated musculoskeletal abnormalities, including club foot and dislocation of the hip. We saw twelve patients with this disease, four of whom required extensive orthopaedic treatment.

Abdominal Muscles↗
PubMed1977

Some medicolegal aspects of gunshot wounds.

While we concede that sleuthing is not the realm of a surgeon, we believe that there is a clear need for better communication among all concerned with shooting injuries. Along with good medical management we make a plea for more accurate case documentation and better preservation of evidence. Not only will better records greatly aid police investigations, but more understanding of the medical aspects of these wounds will also doubtless ensue. We recommend the use of photography whenever possible, and careful preservation of all physical evidence. Finally, to facilitate documentation in gunshot cases we suggest the routine use of a standardized checklist.

Forensic Medicine↗