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Biomedical subjects

H Tao

Publications and source records attributed to H Tao.

78 records · Page 5Linked to original sources
PubMed1983

Changes in plasma concentrations of thyroxine, triiodothyronine, cholesterol and total lipid in beef steers fed ronnel.

An experiment with eight beef steers was conducted to determine the patterns of change for plasma concentrations of thyroxine (T4), triiodothyronine (T3), cholesterol and total lipid following the addition or withdrawal of the organophosphate, ronnel, from the diet. Steers were fed 0, 2, 4 and 8 mg ronnel/kg body weight daily in a Latin square arrangement of treatments with five 28-d periods. Plasma samples were obtained at -2, 1, 3, 5, 7, 9, 16 and 23 d of each period. Steers had not received ronnel before period 1 and, for periods 2 to 5, steers previously fed the lower levels (0 and 2 mg ronnel) were switched to the higher levels (4 and 8 mg ronnel) and steers previously fed the higher levels were switched to the lower levels. Treatment assignments for periods 1 and 5 were the same. Feed intake was similar for all treatments (7.8 kg/d) and daily gain was greater when ronnel was fed (.65 vs .88 kg). Plasma T4 concentrations increased positively in response to ronnel level within the first day after ronnel feeding began and reached a plateau within 3 d. Plasma T4 concentrations decreased following the withdrawal of ronnel, but the response was slower; a lower level being established within about 7 d. Changes in plasma T3 concentrations were small, but were concurrent with plasma T4 changes and were inversely related to ronnel level. Plasma cholesterol concentrations tended to be positively related to ronnel level, but changed slowly with time; plasma total lipid concentrations were not consistently affected by ronnel level. The results of this experiment demonstrate that ronnel has an immediate effect on thyroid function in beef steers.

Animals↗
PubMed1982

Does uncomplicated diverticular disease produce symptoms?

A questionnaire dealing with bowel symptoms was administered to 97 outpatients referred for air-contrast barium enema. Subsequently, the barium enema was interpreted by a radiologist who did not know the results of the questionnaire. Forty-nine had normal x-rays, and 27 had uncomplicated diverticular disease. Weight loss, rectal bleeding, abdominal pain, and pain at night were as common in those with a normal examination as in those with diverticula. Symptoms of colon dysfunction included abdominal pain relieved by defecation, altered stool frequency and consistency with pain onset, abdominal distension, feeling of incomplete evacuation after defecation, and mucus in the stool. These were equally prevalent in both groups. Therefore, no symptoms could be ascribed to the presence of diverticula.

Abdomen↗
PubMed1982

The structural analysis of hemoglobin Handsworth.

The present paper describes the structural analysis of an abnormal hemoglobin variant of alpha-chain found in a Chinese woman in the Hechi district of the Zhuang Autonomous Region of Guangxi, and finds it to be hemoglobin Handsworth (alpha 18(A16) Gly leads to Arg).

Amino Acid Sequence↗
PubMed1981

Effects of ronnel on growth, endocrine function and blood measurements in steers and rats.

Four feeding trials were conducted to determine (1) how the organophosphate ronnel affects thyroid and adrenal circulating hormone levels and blood profile measurements of beef steers and (2) whether the effects of ronnel observed in beef steers could be produced in growing rats. In trial 1, four groups of eight steers each were given either no ronnel or 4 mg ronnel/kg body weight daily in diets fed at either limited (1.8% of body weight) or ad libitum intake. After 7 weeks, intake levels, but not ronnel treatments, were reversed during a 1-week transition period, and feeding was continued for another 7 weeks. In trial 2, four groups of six steers each were given 0, 44, 88 or 176 ppm ronnel premixed in diets fed ad libitum for 18 weeks. Actual ronnel intakes averaged 0, 1.01, 2.12 and 4.73 mg/kg body weight daily in trial 2. In trials 3 and 4 , growth and intake were measured in 64 and 32 growing Sprague-Dawley rats, respectively, fed levels of ronnel ranging from 0 to 100 ppm in the diet. In trial 3, blood plasma was analyzed at various times for triiodothyronine (T3), thyroxine (T4), cholesterol and total lipid content. In trial 1, the concentration of Plasma T4 was 1.31 times higher in steers fed ronnel that in control steers. In trial 2, plasma T4 was 1.30 times higher in steers fed 176 ppm ronnel, the level that improved growth, than in steers fed the lower ronnel levels. Circulating levels of T3, cortisol and aldosterone were similar for both control and ronnel-fed steers. Serum cholesterol concentrations were consistently higher in ronnel-fed steers. The data indicated that the growth-promoting effect of ronnel in steers may be associated with a shift in thyroid function. Effects of ronnel in steers were not observed in rats, demonstrating a species difference between steers and rats.

Aldosterone↗
PubMedDate not supplied

The effects of 1,25-dihydroxyvitamin D3 on osteoclast formation in fetal mouse metatarsal organ cultures.

We have previously described a model system, using 15-day fetal mouse metatarsals cultured in serumless medium, in which osteoclasts and their precursors develop from in situ progenitors in a manner which is similar, both temporally and spatially, to that which occurs in vivo. In this report we evaluate the role of the osteotropic hormone 1,25-dihydroxyvitamin D3 (1,25-D3) on osteoclast formation in this model system by characterizing its effects on proliferation, differentiation, and fusion of cells of the osteoclast lineage. Morphologic evaluation was used to enumerate osteoclast precursors, mono- and multinucleate osteoclasts, and osteoclast nuclei in serial paraffin sections. Dose response data reveal a significant stimulation of osteoclast formation by 1,25-D3 in the range of 0.6 nM to 40 nM, and kinetic analyses suggest that these effects are on proliferation of osteoclast progenitors as well as on differentiation of precursors to form osteoclasts. A single 48 h exposure between day 4 and 6 of culture is necessary and sufficient to induce maximal osteoclast formation, while continuous exposure beyond this "critical period" inhibits multinucleate osteoclast formation. Simultaneous treatment with indomethacin inhibits the effects of 1,25-D3, while treatment with PGE2 stimulates osteoclast formation without significantly increasing precursor numbers, or inhibiting multinucleate osteoclast formation. These results suggest that the effect of 1,25-D3 to induce differentiation of precursors to form mono- and multinucleate osteoclasts is mediated by endogenous prostaglandin synthesis. On the other hand, the inhibition of polykaryon formation observed with continuous 1,25-D3 treatment, does not appear to be a prostaglandin mediated phenomena.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗