in vivo depression of lymphocyte traffic in sheep by vip and hiv (aids)-related peptides.core pentapeptides and an octapeptide (peptide t) computer deduced from amino acid sequences from vasoactive intestinal peptide (vip) and the 120 gp external envelope of the hiv (aids) virus and synthesized have been reported to have important in vitro and in vivo activity including inhibition of hiv binding to cd4 surface antigens of brain cells and lymphocytes and limitation of hiv infectivity. two of these core pentapeptides, peptide ttnyt (peptide t [4-8]) and peptide tdnyt (vip [7-11]), are ...19883267011
thyroid hormone effects on neonatal is clear that thyroid hormones modulate non-shivering heat production of the newborn mammal. while some obvious thyroid hormone effects on thermogenesis can be demonstrated in adult, cold-acclimated or hibernating animals, these findings cannot be directly applied to the newborn, in which changes in amount and composition of brown adipose tissue, as well as sympathetic and thyroid system maturational events, are occurring. thyroid hormones do influence the prenatal development and subsequent ...19883293226
ontogeny of ovine lymphocytes. ii. an immunohistological study on the development of t lymphocytes in the sheep fetal spleen.the development of t and b lymphocytes in the ovine fetal spleen was studied immunohistologically using a panel of monoclonal antibodies. a specific sequence of appearance of lymphocyte markers on cells was observed. at 43-44 days of gestation, sbu-t1- and sbu-t8-positive lymphocytes were present in low numbers. however, no sbu-t4, 20.96-, 25.69-, 38.38-, or 46.66-positive lymphocytes were seen until 50-55 days of gestation. surface immunoglobulin (sig) was first detected on fetal spleen cells a ...19873308689
ontogeny of ovine lymphocytes. iii. an immunohistological study on the development of t lymphocytes in sheep fetal lymph nodes.the development of t lymphocytes in ovine fetal lymph nodes was studied immunohistologically using a panel of monoclonal antibodies. t lymphocyte subsets appeared within the ovine fetal lymph node in a specific sequence. sbu-t1- and sbu-t8-positive lymphocytes were seen at day 47 of gestation. lca, sig, mhc i, mhc ii, sbu-t6 and 46.66 antigens were also seen within the lymph node at this time. the first sbu-t4-positive cells were seen within the fetal lymph node at day 50 of gestation, along wit ...19873308690
ontogeny of ovine lymphocytes. i. an immunohistological study on the development of t lymphocytes in the sheep embryo and fetal thymus.the time of appearance of lymphocytes expressing t-cell markers and the subsequent development of the fetal thymus were studied in ovine embryos using a panel of monoclonal antibodies. leucocyte common antigen (lca) and major histocompatibility complex class i (mhci) antigens were seen on a small number of cells within the ovine embryo at day 19 of gestation. sbu-t6 (cd1)-positive cells were found at day 22 of gestation, while major histocompatibility complex class ii (mhc ii) antigens were firs ...19873308692
preferential saturation of brain 3,5,3'-triiodothyronine receptor during development in fetal lambs.the concentrations of t4 and t3 were measured in brain, liver, and lung of fetal lambs at 100 days gestational age. the highest concentrations of t4 were found in lung (26.8 ng/g). brain t4 (8.8 ng/g) was only 30% of lung t4. in contrast, higher concentrations of t3 were found in brain (1.8 ng/g) than in lung (0.39 ng/g) or liver (0.36 ng/g). nuclear t3 was 16% of the total t3 in brain and 44% of that in lung. the degree of saturation of the nuclear t3 receptor was estimated from the concentrati ...19883338407
ontogeny of thyroid hormone effect on tissue 5'-monodeiodinase activity in fetal sheep.most of the thyroxine (t4) in fetal mammals is deiodinated to the inactive metabolite, reverse triiodothyronine (rt3), via an iodothyronine 5-monodeiodinase in fetal tissues. maturation of the tissue 5'-monodeiodinase (mdi) enzymes required for conversion of t4 to active triiodothyronine (t3) in the rat, an altricial species, occurs in the postnatal period. to characterize fetal maturation of the enzymes for active t3 production in a precocial species, 5'-mdi activities were measured in liver, k ...19883348392
effects of propylthiouracil (ptu) on the immunological status of the chicken.effects of propylthiouracil (ptu) using different treatment schedules on immune functions in young male chicken were studied. antibody productions to sheep red blood cells (srbc) and brucella abortus (ba) were found to rise in the chicks treated with 0.1% and 1% ptu. furthermore, the chicks treated with 1% ptu exhibited a significantly greater reaction to phytohemagglutinin (pha) in skin test using the wing web than the control did. treatment of 5% ptu, however, inhibited the antibody production ...19883350187
dietary calcium and metacarpal growth in ewes.the effects of excess dietary calcium on bone growth were quantified in 44 ewes fed ad libitum diets that contained one of four levels of dietary calcium (0.37, 0.56, 1.13 and 1.80%) and 0.42% phosphorus. animals were slaughtered at one of six ages, circulating concentrations of hormones and minerals were measured and bone morphometry was evaluated. none of the diets impaired normal bone growth of the metacarpal as evaluated by overall length, cortical index and growth plate width. circulating p ...19883404288
depression of lymphocyte traffic in sheep by vasoactive intestinal peptide (vip).vasoactive intestinal peptide (vip) is a 28 amino acid-residue neurovascular and gut peptide with a number of important biological activities. recent in vitro studies suggest an immunomodulatory (depressant) role for vip. in the present in vivo studies, employing the hall and morris sheep lymphocyte traffic model, acute infusions of vip into cannulated afferent lymphatics of popliteal lymph nodes produced prompt and marked depressions in the output of both small recirculating and blast lymphocyt ...19883410493
[dynamics of thyroid hormones and hematological and biochemical indices in chronic nitrate poisoning in sheep].experimental researches were carried out on sheep, fed with forage, containing 0.6% nitrate in the dry substance of the ration with the aim to follow the dynamics of the thyroid hormones, respectively the functions of the thyroid gland and its connection with some hematologic and biochemical indexes in the blood (methaemoglobin, blood sugar, carotene and vitamin a). it is ascertained that t3 and t4 decrease during the development of chronic nitrate poisoning, and the blood sugar and methaemoglob ...19873450082
epidermal growth factor: effect on circulating thyroid hormone levels in sheep.observations on the effect of thyroid hormones on mouse submaxillary gland epidermal growth factor (egf) and on the complementary effect of egf on cultured thyroid cells led us to examine the interaction between egf and thyroid hormones in the whole animal, during and after 24 h of infusion of 3.3 micrograms/kg x h mouse egf into 6 merino ewes. there was a profound depression of both circulating t4 and t3 levels, to less than 20% of saline-infused control values, extending beyond the end of infu ...19863487443
immune rosettes of t and b lymphocytes in infertile women with endometriosis.we examined the cell-mediated immune response in women with pelvic endometriosis by quantitating their t and b lymphocytes. the study was conducted on heparinized peripheral blood and peritoneal fluid. the results were compared with those in a control group of women without evidence of endometriosis. each patient underwent laparoscopy as part of her infertility evaluation. the ability of t cells to form rosettes with sheep erythrocytes was used to estimate the percentage of total and active t ce ...19873494842
in vivo labeling of blood t cells: rapid traffic into cerebrospinal fluid in multiple sclerosis.multiple sclerosis (ms) is an inflammatory disease of the central nervous system (cns). in ms patients being treated with anti-t11, a murine monoclonal antibody which recognizes the sheep red blood cell receptor, it was found that peripheral blood t cells were labeled in vivo by the antibody. furthermore, anti-t11 did not lyse cells or enter the cerebrospinal fluid (csf). in csf specimens obtained by serial lumbar punctures from patients with progressive ms who received five daily infusions of a ...19873498435
effect of altered thyroid hormone levels on hypothalamic-pituitary-adrenal determine whether alterations in serum thyroid hormone levels affect hypothalamic-pituitary-adrenal function, we measured the plasma immunoreactive (ir) acth and ir-cortisol responses to 1 microgram/kg bw ovine crh (ocrh) given iv in the late afternoon and the plasma ir-acth, ir-cortisol, and ir-11-deoxycortisol responses to 2 g metyrapone given orally at midnight in 10 athyreotic patients during t4 treatment and 1 month after stopping t4 when they were biochemically, but not clinically, hypo ...19873499449
perinatal thyroid activity in farm animals and the role of iodocompounds in maternal milk (minireview).there is a sudden rise in serum thyroid hormone concentrations immediately after birth, with some species differences related to the degree of the increase and to the iodothyronine involved. extrauterine cooling stimulates tsh release; however, the marked release of the thyroid hormones from the gland is somewhat dependent on the process of transition from fetal to neonatal state. it seems that hemodynamic changes together with the sympathetic nervous system, which comes in force at the moment o ...19863530716
effect of hypophysectomy with and without thyroxine replacement on growth and circulating concentrations of insulin-like growth factors i and ii in the fetal lamb.the role of the pituitary gland in the regulation of skeletal growth and plasma insulin-like growth factor (igf)-i and igf-ii concentrations in the late gestation sheep fetus has been studied. singleton fetuses were either hypophysectomized (n = 14) or sham operated (n = 8) between days 110 and 125. fetal and maternal blood samples were collected three times weekly through the remainder of gestation. in some hypophysectomized fetuses (hxt4 group, n = 4), t4 was administered (100 micrograms l-t4/ ...19873569114
regulation of differentiated thyroid function by iodide: preferential inhibitory effect of excess iodide on thyroid hormone secretion in sheep thyroid cell cultures.primary cultures of sheep thyroid cells have been used to study the inhibitory effects of iodide on thyroid function. under the influence of tsh, iodide was concentrated with a cell to medium ratio of 20. when thyroid hormone secretion was measured from cells cultured without addition of exogenous iodide, preferential t3 secretion was evident. the optimum iodide concentration for t4 and t3 synthesis and secretion was 10(-6) m. prior exposure to 10(-5) m or more iodide decreased subsequent iodide ...19873569143
effects of food restriction on cortisol, tsh and iodothyronine concentrations in the plasma of the newborn lamb.the influence of food restriction, applied from birth to 36 h post partum, on neonatal thyroid function was studied in newborn limousin x romanov lambs. the control animals (n = 18) had free access to the mother and suckled ad libitum. restricted lambs (n = 16) were removed from the mother and received limited amounts of colostrum in proportion to birth weight; 8 lambs were supplemented with lactose (30 g/l of colostrum). plasma glucose and free fatty acid levels were significantly lower in rest ...19873616134
cellular composition of peripheral lymph and skin of sheep defined by monoclonal antibodies.the surface phenotype of cells in peripheral lymph collected from afferent lymphatics leading to the popliteal lymph node of sheep was determined using a panel of monoclonal antibodies (mabs). the majority of lymphocytes (83.5%) expressed the sheep pan-t cell antigen and only 13.3% bore surface immunoglobulin molecules. all peripheral t cell subsets occurring in sheep were detected; 50.2% of lymphocytes were positive for mab sbu-t4 (t helper), 7.3% were positive for mab st-8 (t cytotoxic), and 8 ...19873654007
ontogenesis of thyroid hormone receptor in foetal lambs.affinity and concentration of t3 receptor sites have been measured in nuclear extracts from the brain, lung, and liver of foetal lamb tissues at 50, 82 and 100 days of gestational age. control experiments indicated that the concentration of sites was similar when nuclear extracts or purified nuclei were used, and that maximal binding capacity was obtained after 2 h of incubation at 22 degrees c. the pattern of receptor binding affinity when different thyroid hormone analogs were used in competit ...19873661061
neonatal changes in plasma cortisol, free and total iodothyronine levels in control and hypotrophic lambs.neonatal changes in plasma free and total iodothyronines, cortisol, glucose and urea levels have been studied in 8 control (birthweight greater than or equal to 2.5 kg) and 16 hypotrophic lambs (birthweight less than 2.5 kg) receiving limited amounts of colostrum during the first 36 h of life and then fed ad libitum. during the period of colostrum feeding, plasma glucose levels were low in both groups and increased after the onset of ad libitum feeding; they were significantly lower in hypotroph ...19873685619
thyroid function in newborn lambs: influence of prolactin and growth hormone.lambs originating from suffolk, milksheep and texel crossbreeds were injected with saline, 500 micrograms ovine prolactin or 500 micrograms ovine gh within 30 min of parturition (n = 10). birth weight was negatively correlated with plasma concentrations of reverse tri-iodothyronine (rt3) but not with thyroxine (t4), free t4 (expressed as the free thyroxine index) or cortisol. at birth, t3 and t4 plasma concentrations were high and remained high during the 3-h observation period. after 3 h a sign ...19863711760
the effect of maternal thyroidectomy prior to conception on foetal brain development in sheep.merino ewes were surgically thyroidectomized, and mated 6 weeks later when their plasma thyroxine (t4) levels were negligible. their foetuses were delivered by hysterotomy at 52, 71, 84, 98, 125, 140 days gestation or at term (150 days). despite the very low levels of t4 in maternal plasma, the concentrations of t4 in foetal plasma were not significantly different after 71 days gestation from those of foetuses of sham-operated (control) ewes. foetal brain and body weights, however, were reduced ...19863716760
serum thyroid hormones and tissue 5'-monodeiodinase activity in acutely thyroidectomized newborn lambs.after either total thyroidectomy or sham operation in full-term fetal sheep, fetuses were delivered and serial blood samples were obtained for measurements of thyroxine (t4), triiodothyronine (t3), and catecholamines. despite comparable serum t4 values (t4 means +/- se, sham 7.1 +/- 0.6 micrograms/dl, thyroidectomized 6.8 +/- 0.7 micrograms/dl at 60 min after birth), serum t3 values were lower in the thyroidectomized animals (t3 means +/- se, thyroidectomized 39 +/- 4.8 ng/dl, sham 153 +/- 20.1 ...19863740254
relationship between circulating thyroid hormones and humoral immunity in immature male chickens.the objective of this experiment was to examine the relationship between levels of circulating t3, t4, and humoral immunity in immature male chickens. three week old single comb white leghorn male chicks were used as the experimental animals. in order to produce a wide range of circulating thyroid hormone concentrations, birds were divided into groups and received one of nine treatments including surgical thyroidectomy; 0.1% propylthiouracil (ptu) in the feed; 1 ppm t3 and 10 ppm t4 in the feed. ...19863770270
the effect of dodecyl sulfate on immunoglobulin hapten binding.the instantaneous effect of dodecyl sulfate (dds), in the mm concn range, on the binding of monovalent hapten by immunoglobulin was examined. fluorescence measurements were utilized to study the effect of the detergent on sheep antiserum generated against thyroxin (t4) and against methamphetamine. haptens were conjugated with the thiocyanate derivative of fluorescein in order to determine hapten binding on the basis of increased fluorescence polarization for the fluorescein-thiocarbamyl-hapten a ...19863785231
plasma free and total iodothyronine levels in the newborn lamb. physiological considerations.neonatal changes in plasma total and free iodothyronine levels were monitored in 18 limousin x romanov suckling lambs (experiment 1) and 24 limousin x romanov animals bottle-fed in standardized conditions (experiment 2). in the two experiments, plasma free t3 levels were closely related to total t3 levels, whereas some differences could be observed between total and free plasma t4 levels. the neonatal rise in free t4 in particular was higher than that observed for total t4 levels. consequently, ...19863823603
multiple class i and class ii major histocompatibility complex allospecificities are generated with t cell receptor variable (v) domains created by a single ti beta v gene family.10 alloreactive cytotoxic t lymphocytes using rex ti beta variable region (v) gene segments in formation of their antigen/major histocompatibility complex (mhc) t3-ti receptor were selected, cloned, and characterized in an effort to examine the extent of receptor diversity created by this one v gene family. multiple and distinct class ii as well as class i allospecificities were generated from the formation of different ti beta v domains. five allospecificities were directed at various class i e ...19853862747
evaluation of t cell subsets in behçet's syndrome using anti-t cell monoclonal antibodies.several immunological abnormalities have been described in behçet's syndrome, the multisystem disease characterized by the triad of relapsing iridocyclitis with recurrent oral and genital ulcerations. in the present study we have evaluated t cell subsets in the peripheral blood of patients suffering from behçet's syndrome, using a panel of anti-t cell monoclonal antibodies. when compared with normal subjects, patients with behçet's syndrome show a discrepancy between the number of t3+ cells and ...19853874016
acute leukemia of hybrid phenotype: t lymphoid and myelomonocytic markers.several unique phenotypical and functional characteristics were found together in a patient with acute poorly differentiated leukemia. the blast cells showed an unusual t-cell phenotype, forming spontaneous rosettes with sheep red blood cells and expressing the t11 antigen, but were negative for the other immature or mature t markers tested--leu-1, 3a1, t3, t4, t8, t9, t10, t6, and tdt--and reacted with the monoclonal antibody okm1 expressed by myeloid lineage cells and which is also present in ...19853878245
surface antigens, sbu-t4 and sbu-t8, of sheep t lymphocyte subsets defined by monoclonal antibodies.monoclonal antibodies have been used to characterize molecules found on the surfaces of t cells of sheep. sbu-t4 and stu-t8 are present on 80-85% of thymocytes, absent from b lymphocytes, and present on two-thirds and one-third of lymph node t lymphocytes, respectively. double-labelling of t lymphocytes shows that the populations recognized are mutually exclusive. immunoprecipitation of the sbu-t4 antigen from thymocytes and t lymphocytes reveals a molecule which migrates on sds-page as a single ...19853894225
endocrine activity in preterm and full-term lambs. 1. adrenal response to synacthen. 2. thyroid response to ovine thyroid-stimulating hormone or thyrotropin-releasing hormone.neonatal endocrine status was studied in 14 lambs born 7 days before term, after estrogen injection into the ewes, and in 15 full-term animals. plasma cortisol and triiodothyronine (t3) levels were depressed during the first hours of life in preterm lambs and plasma reverse t3 levels were significantly higher than in controls. the rise in plasma cortisol levels after synacthen injection was significantly lowered by prematurity, suggesting reduced sensitivity of the adrenal cortex to acth. after ...19853924127
thyroid hormone binding in serum of 15 vertebrate species: isolation of thyroxine-binding globulin and prealbumin analogs.the binding of [125i]t4 to serum proteins was studied in human, monkey, cattle, sheep, goat, water buffalo, horse, swine, dog, cat, rabbit, rat, chicken, frog, and salmon. attempts were made to isolate thyroxine-binding globulin (tbg) and thyroxine-binding prealbumin (tbpa) from serum of all species, utilizing purification methods based on the specific properties of these proteins. tbpa was found to exist in all species examined. the protein was found anodal to albumin only in human, monkey, hor ...19853924724
[light entrainment and stimulation of the secretion of prolactin in rams].light entrainment and stimulation of prl release were studied in rams submitted to artificial light regimes: in a first experiment four groups of animals were submitted to light regimes with a period of 6, 4, 3 or 2 months respectively (t6 to t2 groups) and amplitude of 8-16 h of daylength. in all four groups prl level was significantly correlated with daylength (r greater than 0.51; p less than 0.01). however in july, when temperatures were indeed high, an additional prl increase was observed i ...19853928108
activity of the hypothalamo-pituitary axis and testicular development in prepubertal ram lambs with induced hypothyroidism or hyperthyroidism.prepubertal (16 weeks old) ram lambs were used to investigate the effects of hyperthyroidism and hypothyroidism on development of reproductive endocrine function. over a period of 8 weeks, ram lambs were made hypothyroid (serum t4 less than or equal to 3 ng/ml compared with controls congruent to 30 ng/ml) by daily oral administration of methyl thiouracil or hyperthyroid (serum t4 congruent to 135 ng/ml) by daily sc injection of t4. hyperthyroidism was associated with decreases in lh pulse freque ...19853928336
purification, characterization and immunological properties of the capsular polysaccharide of pasteurella haemolytica serotype t15: its identity with the k62 (k2ab) capsular polysaccharide of escherichia coli and the capsular polysaccharide of neisseria meningitidis serogroup h.capsular polysaccharide from two strains of pasteurella haemolytica serotype t15 was purified and characterized by chemical analysis and nmr spectroscopy. the polymer, a teichoic acid, proved to be very similar in structure to the capsular polysaccharide of p. haemolytica serotype t4 and identical to the previously described k62 (k2ab) capsular polysaccharide of escherichia coli, and the capsular polysaccharide of neisseria meningitidis serotype h, i.e. ----(2-glycerol-3)----(phosphate)----(4-al ...19853932592
[partial abolition of seasonal variations of testicular weight in rams by decreasing the photoperiod].under moderate latitudes all breeds of rams undergo seasonal variations in testicular weight with a maximum during summer under decreasing daylength ([1]-[4]). similarly, in rams submitted to a 6-month artificial light regime [5] or to an alternation of long (16l:8d) and short (8l:16d) days [6] an increase in testicular weight occurred following a decrease in daylength and vice versa. however this effect is transitory, a phenomenon which can be referred as photorefractoriness. in the present stu ...19853936602
total and free serum thyroid hormone concentrations in fetal and adult pregnant and nonpregnant guinea pigs.information on total and free serum thyroid hormone concentrations in the adult and fetal guinea pig (cavia porcellus) is limited. these variables were studied in adult male and female guinea pigs and in pregnant guinea pigs and their fetuses at various times during gestation. total serum t4 levels in adult males, nonpregnant females, and pregnant females did not differ significantly [range, 2.5 +/- 0.3 to 3.2 +/- 0.8 micrograms/dl (mean +/- sd)]. similarly, there were no significant differences ...19863943484
chemiluminescent labeled-antibody assay for thyroxin in serum, with magnetic separation of the solid-phase.a chemiluminescent labeled-antibody immunoassay has been developed for measurement of total thyroxin (t4) in serum. monoclonal antibodies to t4 labeled with a chemiluminescent acridinium ester are used. serum samples are incubated with the labeled antibodies and a thyroxin-rabbit immunoglobulin conjugate, then reacted with magnetizable particles containing sheep anti-rabbit immunoglobulin. the total reaction time is 40 min. the chemiluminescence intensity of the solid-phase immune complexes is i ...19863948401
biochemical and ontogenic characterization of thyroxine 5'-monodeiodinase in brown adipose tissue from fetal and newborn lambs.we characterized t4 5'-monodeiodinase (5'-mdi) and its ontogenic changes in brown adipose tissue (bat) of fetal lambs from a gestational age of 99 days to the newborn period. bat 5'-mdi activity in fetal or newborn lamb was markedly enhanced by dithiothreitol (dtt); a near-maximum stimulation was reached at a dtt concentration of 1 mm. the enzyme is heat-labile (inactivated when heated to 56 c for 5 min) and has a ph optimum at 6.5. in the presence of 1 mm dtt, bat 5'-mdi was extremely sensitive ...19863948783
the mechanism of low serum t3 in the fetus: hepatic t4-5'-monodeiodinase versus tissue sulfhydryl content--a clarification.using optimal tissue concentration, supplemented with a thiol-protecting agent, the fetal liver has lower t4 5'-monodeiodinating activity than maternal or neonatal tissue. this is a true deficiency and is not due to deficiency of sulfhydryl groups in fetal tissue as previously suggested. evidence indicates a dissociation of the neonatal surge of serum t3 and the increase in hepatic t4 to t3 conversion activity, suggesting that the neonatal t3 surge is related more to thyroid gland stimulation th ...19863958442
stimulation of renal deoxyribonucleic acid synthesis by a pituitary-derived renotropin and its inhibition by testosterone and thyroxine.kidney slices were obtained from castrated-hypophysectomized male rats treated with a single injection of several different gonadotropin preparations (two ovine lh fractions, one bovine lh fraction, and one hcg fraction) or vehicle, then incubated in a buffer containing [3h]thymidine. only one of the above, an ovine lh preparation, increased [3h]thymidine incorporation into renal dna, with a peak occurring 8-10 h after injection and therefore termed renotropin. however, in hypophysectomized rats ...19853967623
purification, characterization and immunological properties of the serotype-specific capsular polysaccharide of pasteurella haemolytica (serotype t4) organisms.the serotype-specific capsular polysaccharide from two strains of pasteurella haemolytica serotype t4 organisms was purified and characterized by chemical analysis and nmr spectroscopy. the polymer, a teichoic acid, has the backbone structure ----(2-glycerol-l)----(phosphate)----(6-alpha-d-galactose-1)---- and is partially o-acetylated on the c2 and c3 galactose residues. chemical removal of o-acetyl groups from the polysaccharide destroyed both its ability to precipitate with antiserum raised a ...19853981132
endocrine regulation of metabolism in sheep given kale (brassica oleracea) and ryegrass (lolium perenne)-clover (trifolium repens) fresh-forage diets.diets of fresh kale (brassica oleracea) and ryegrass (lolium perenne)-clover (trifolium repens) herbage were fed to growing sheep in three experiments. in expts 1 and 3 the sheep were confined indoors and fed at hourly intervals, and all were given supplementary iodine to counteract kale goitrogens. lambs grazed the two forages for 24 weeks in expt 2, with and without intramuscular injections of iodized oil. the kale and herbage contained respectively 11 and less than 0.1 g s-methyl-l-cysteine s ...19854063301
plasma free and total iodothyronine levels in hypophysectomized and intact lamb foetuses during the last third of gestation.the changes in plasma levels of thyroxine (t4), free thyroxine (free t4), triiodothyronine (t3), free triiodothyronine (free t3), and reverse triiodothyronine (rt3) were observed in intact or hypophysectomized lamb foetuses during the last third of gestation. hypophysectomy was performed at two stages: 100 and 120 days of gestation. cord blood was collected after caesarean section. in intact foetuses, t4 and free t4 levels increased significantly between day 100 and 120 of gestation, but decreas ...19854072578
studies on experimental growth retardation in sheep. the effects of a small placenta in restricting transport to and growth of the fetus.fetal and placental growth rate in sheep has been manipulated by removal of endometrial caruncles prior to conception. this produced two groups of fetuses, one in which prenatal growth rate was similar to normal and a second group in which the fetuses were about half of the normal size. the mortality in the latter group was high, particularly after catheterisation, and there was evidence of early intra-uterine death and fetal reabsorption. prior to 125 days the relationship between fetal and pla ...19854078258
a sheep preparation for studying interactions between blood flow and drug disposition. iv: the effects of general and spinal anaesthesia on blood flow and cefoxitin disposition.control measurements of blood flow through and cefoxitin extraction ratios across heart and lungs, liver, kidneys and gut were made under steady-state conditions in awake unrestrained sheep. the studies then were repeated with the same animals anaesthetized with 1.5% halothane or whilst undergoing high thoracic (to approximately t4) subarachnoid blockade with amethocaine. in the control-drug studies, it was shown that cefoxitin was cleared by the kidneys and that the cefoxitin infusion produced ...19854084430
combined hormonal treatment and lung maturation.despite the proven efficacy of glucocorticoids for the prevention of rds, this treatment is not effective in every case. one possible approach to improving the outcome is combined treatment with thyroid hormone and corticosteroid. thyroid hormones accelerate morphological development and surfactant production in animals after treatment in vivo. with lung tissue in culture, t3 enhances phospholipid synthesis, apparently acting at different biochemical sites from those stimulated by corticosteroid ...19846093266
adult t-cell lymphoma-leukaemia in blacks from the west indies.six black patients (five born in the west indies and one in guyana), aged 21-55 years, had adult t-cell lymphoma-leukaemia diagnosed in the u.k. this disorder is rare in europe and the u.s.a., but is more common in japan. five patients had severe hypercalcaemia which correlated with disease activity, although osteolytic lesions were found in only one. other clinical features were lymphadenopathy and a high white blood-cell count (range 27-67 x 10(9)/l) with a predominance of pleomorphic lymphoid ...19826121963
attenuation by hypocalcemia of pulsatile growth hormone secretion in conscious male rats.the effect of hypocalcemia following parathyroidectomy (ptx) on growth hormone (gh) secretion was investigated in unrestrained, unanesthetized male rats bearing chronically implanted indwelling cannulae. during a 6-hour period, starting at about 10 a.m., control rats with a serum calcium (ca) value of 8.11 +/- 0.38 mg/dl (mean +/- sem) 2 weeks after sham-operation showed secretory bursts of gh similar to those observed in conscious intact rats. under hypocalcemia of 4.88 +/- 0.32 mg/dl 2 weeks a ...19826130487
thyrotropin secretion in starved rats is enhanced by somatostatin antiserum.previous studies have demonstrated that serum tsh and gh decrease during fasting. taking advantage of the fact that somatostatin antiserum administration is an effective, specific method of blocking endogenous somatostatin activity, we performed the present investigation to explore whether known fasting-induced increases in somatostatin might underlie the mechanism(s) of this decrement. after a 48 hour fast, two groups of male rats were anesthetized and an indwelling right atrial catheter insert ...19846142853
restricted antigenicity of thyroxyls in human thyroglobulin.interactions between two human iodothyronine-binding autoantisera and three preparations of human thyroglobulin (tg) were not proportional to the latter's thyroxyl residue content. probably only one of the several thyroxyl-containing sites in tg reacted with the immunoglobulins from both antisera. in the case of one of the antisera, which was thyroxine (t4)-specific, the thyroxyl residue was the immunodominant feature of the antigenic site. the other antiserum, which had a specificity for 3,5,3' ...19826187336
neuropeptides in the thyroid gland: distribution of substance p and gastrin/cholecystokinin and their effects on the secretion of iodothyronine and calcitonin.previously, vasoactive intestinal polypeptide was localized to intrathyroidal nerve fibers. it stimulates iodothyronine secretion in mice. in the present study two populations of nerve fibers containing substance p and gastrin/cholecystokinin (cck)-like immunoreactivity, respectively, were demonstrated in the thyroid gland of several mammals. the substance p fibers occurred around blood vessels and follicles, whereas the gastrin/cck fibers occurred mainly around follicles. in the chicken thyroid ...19836190643
human newborn autologous mixed lymphocyte response: frequency and phenotype of responders and xenoantigen specificity.the response of human newborn lymphocytes in autologous mixed lymphocyte culture was examined for specificity (by restimulation), responder cell phenotype, and responder cell frequency. when the newborn t cells were separated from non-t cells by rosetting with sheep erythrocytes (e) in fetal calf serum (fcs), approximately 1:20,000 t cells proliferated. these responders had specificity for e + fcs, were t4+, and were self-restricted. significant numbers of responder t cells were not found when n ...19846203976
the relationship between human t-lymphocyte subsets defined by monoclonal antibodies and by avidity differences to sheep e-rosette sedimentation procedures and fluorescence activated cell sorting of monoclonal antibody-coated t lymphocytes, we have investigated the relationship between the human t lymphocyte subsets defined by the monoclonal antibodies against the t4 and t8 antigens and those defined by avidity differences to sheep erythrocytes. through a correlation was demonstrated between the t4+ (inducer) cells and the high avidity ("active") t cells and between the t8+ (suppressor) cells and low avidity t ...19826211030
[effects of exogenous tsh on the thyroid activity of adult or neotenic amphibians].in adult anuran and neotenic urodela, bred in laboratory conditions, the levels of plasma thyroid hormones are undetectable (t3 less than 50 ng/100 ml, t4 less than 5 ng/100 ml). thyroid function can be reactivated after ovine tsh treatment. under those conditions, metamorphosis is induced in the axolotl and t4 plasmatic levels reaches 0,53 +/- 0,13 micrograms/100 ml and those of t3 9 +/- 2,64 ng/100 ml. in adult anuran, thyroid reactivation under thyrotropic treatment determines an increased se ...19826220788
epinephrine-induced changes in the distribution of lymphocyte subsets in peripheral blood of humans.we have previously demonstrated that mitogen responsiveness of mononuclear cells (mnc) from peripheral blood is reduced after a single injection of epinephrine to human subjects. the purpose of the present study was to characterize the relative distributions of mnc subsets after epinephrine administration using monoclonal antibodies and conventional cell markers. the absolute number of circulating mnc increased 64% within 30 min after injection of epinephrine, and returned to baseline by 2 hr. a ...19836224849
in vitro characterization of human intestinal intraepithelial lymphocytes.enriched populations of human intestinal and colonic intraepithelial lymphocytes were isolated separate from lamina propria lymphocytes. these populations, and peripheral blood mononuclear cells, were characterized for membrane features, lymphocyte subsets, and proliferative potential to the nonspecific mitogenic lectins phytohemagglutinin, concanavalin a, and pokeweed mitogen. all three populations were predominantly t lymphocytes as measured by sheep red blood cell rosettes and monoclonal anti ...19836225690
impairment of the autologous mixed lymphocyte reaction in atopic dermatitis.the t cell proliferative response to autologous non-t cells is termed the autologous mixed lymphocyte reaction (amlr). recent studies have suggested that the amlr represents an inducer circuit for the activation of t8+ suppressor/cytotoxic effector cells. since atopic dermatitis (ad) patients are deficient in t8+ cytolytic t cell function, we investigated the amlr in ad. when sheep erythrocytes were used to separate t cells from non-t cells, the amlr was found to be significantly decreased (p le ...19836226679
rapidly expanded activated human killer cell clones have strong antitumor cell activity and have the surface phenotype of either t gamma, t-non-gamma, or null cells.cloned lymphoid cell lines showing cytolytic activity were derived from natural killer (nk) cell-enriched cell fractions obtained by fluorescence-activated cell sorting of cells that reacted with b73 .1, an nk cell-specific monoclonal antibody (mca). the clones were cultured for more than 30 generations (i.e., more than 10(9) descendants from a single cell). the rapid expansion was achieved by using a special culture system developed for this purpose and based on the use of two types of allogene ...19846233369
[mechanisms of the effect of exogenous thyroxine on the regulation of the immune response in mice].the influence of repeated administration of thyroxin (t4) in doses of 4 or 4000 micrograms/100 g body weight daily upon t-b co-operation and specific t-suppressor formation was studied on cba male rats. a stimulating effect of t4 low doses on the lymph node t-cell ability was demonstrated to co-operate with the normal marrow b-cells over a process of generation of the humoral response to the sheep red blood cells within the system of singeneic transfer. the injection of various t4 doses to donor ...19846236457
e-receptors mediate the attachment of activated t-lymphocytes to human red blood cells: evidence from studies with monoclonal antibodies and simple sugars.lectin-stimulated human t-lymphocytes display the capacity of forming stable e-rosettes with sheep red blood cells (srbc) and of forming rosettes with allogeneic and autologous erythrocytes (rbc). fractionation experiments indicated that the same subpopulation of lymphocytes displays both of these characteristics. exposure of t-lymphocytes stimulated with concanavalin a (con a) or phytohemagglutinin (pha) to t11 monoclonal antibody (directed against the e-receptor) completely blocked the formati ...19846334752
immunological markers of human mononuclear cells.the immune response to an antigenic challenge results from complex intercellular communications between several populations of lymphoreticular cells. immunocompetent cells are derived from a common stem cell precursor and develop along two distinct pathways. the t-cell lineage (t-lymphocytes) originates in the thymus and mediates cellular immunity, whereas b-cells (bone marrow derived lymphocytes) mature into antibody producing cells. the maturation of b-cells into plasmacytes is under the contr ...19836349849
induction of cytolytic activity by anti-t3 monoclonal antibody. activation of alloimmune memory cells and natural killer cells from normal and immunodeficient individuals.the ability of the monoclonal antibody directed at the t3 antigen (anti-t3) to induce cytolytic activity was investigated since several agents that can activate t cells induce the acquisition of cytolytic activity in a variety of test systems. pretreatment of human alloimmune memory cells, generated in primary long-term mixed lymphocyte cultures, with anti-t3 resulted in the induction of statistically significant specific secondary cytolytic activity and natural killer (nk) cell-like activity. n ...19846392343
interrelation of the avian immune and neuroendocrine systems.our understanding of immunology and endocrinology has been enriched by studies with different avian species. numerous experiments have identified the role of the avian thymus and bursa of fabricius in the immune response and the interrelation of these glands and their cellular products with the neural endocrine system. the growth pattern of the thymus and bursa are influenced by steroids. increases in thymi growth appear to be controlled, in part, by fluctuations in thyroid activity. sex-linked ...19846394704
effects of thyrotropin-releasing hormone and a thyrotropin releasing hormone analog on growth and selected plasma hormones in 8-wk growth trial was conducted to assess the effects of continuous infusion of thyrotropin-releasing hormone (trh) and an active trh analog less than aad-his-pro-nh2 (the less than aad is l-pyro-alpha-aminoadipic acid) on growth trial performance, carcass composition and hormone profiles of growing lambs. both drugs were infused at 600 micrograms x lamb -1 x d -1 with 16 lambs/treatment. both trh and less than aad-his-pro-nh2 decreased average daily gain (adg; p less than .01) and increased ...19836411671
influence of chronic thyroxine treatment on plasma hormone and metabolite concentrations and on responses to insulin, glucagon and thyrotrophin releasing hormone in adult sheep.four adult sheep fed twice daily were given daily subcutaneous injections of saline for four weeks, followed by a similar period of daily l-thyroxine (t4) injection (1 mg/day). t4 treatment increased basal plasma concentrations of t4, triiodothyronine (t3), insulin and glucose, together with t3-uptake and the free thyroxine index, while cholesterol and urea concentrations decreased. t4 treatment reduced the rise in prolactin levels after the morning meal. thyrotrophin releasing hormone (trh) inj ...19846436158
lung development in the nephrectomized ovine fetus.the effect of fetal nephrectomy on lung development was studied in sheep. fetal kidneys were removed early in the canalicular stage of lung development (95 to 99 days of pregnancy) and lung structure examined during the alveolar stage (125 to 134 days of gestation). progesterone and estradiol 17 beta concentrations in maternal and fetal plasma were normal for gestational age, thus indicating that the ewes were not close to labour at the time the fetuses were removed. mean body weight was signifi ...19846481108
thyroxine and triiodothyronine in milk of cows, goats, sheep, and guinea pigs.milk was collected for the first 21 days of lactation twice daily from dairy cows and once daily from goats, sheep, and guinea pigs. thyroxine (t4) and triiodothyronine (t3) were extracted from 100 microliter of milk using acidified ethanol. t4 and t3 were reconstituted in 100 microliter buffer and measured by radioimmunoassay. concentrations (ng/ml) of t4 and t3 for milk of cows, goats, sheep, and guinea pigs, respectively, were: 0.97 and 0.94, 1.24 and 0.52, 0.99 and 0.79, and 1.41 and 0.53. t ...19846483867
maintenance of differentiated sheep thyroid cells in primary culture for three months.a method is described which permits culture of primary thyroid cells without subculture for at least 100 days. cultures are maintained without medium changes for the entire period, and concentrated glucose is added to replenish energy supplies at carefully defined intervals. the cells retain morphological and functional differentiation shown by light and electron microscopy, pas positive histochemistry, iodine uptake and t4 production for at least 100 days. after this time fairly sudden death of ...19846485705
development of transformed characteristics by sheep thyroid cells irradiated as differentiated primary cultures.a method has been developed which allows four stages of transformation to be detected in subcultured populations of sheep thyroid cells exposed to gamma irradiation as differentiated primary cultures. the cell populations initially irradiated and the subcultures deriving from these retain a number of differentiated properties of thyroid cells, including iodine uptake, follicle formation and t4 production. the stages of transformation which develop in the subcultures are nonsenescence, focus deve ...19846509564
phorbol ester modulation of t-cell antigens in the jurkat lymphoblastic leukemia cell line.the effect of phorbol dibutyrate (pdb) on the cell surface antigens of the human t-cell acute lymphoblastic leukemia cell line, jurkat, was studied with okt monoclonal antibodies by indirect immunofluorescence assay. cells were analyzed in an ortho spectrum iii fluorescence-activated flow cytometer. the surface antigen profile of untreated jurkat cells resembled that of thymocytes; high levels of t3, t4, t6, t8, t9, t10, and t11 antigens were detected. although 89% of cells were positive for t11 ...19836603901
distinctive phorbol ester-induced morphological and surface antigen changes in mycosis fungoides, the sézary syndrome, and adult t-cell leukemia.clinical and pathological studies of cutaneous t-cell lymphomas (ctcl) reveal variations in tumor cell morphology and surface membrane phenotype that are of diagnostic and prognostic importance. our study investigates blastic transformation and surface antigen change on ctcl cells in vitro under the influence of tumor-promoting phorbol ester (tpa) and phytohemagglutinin. both agents transformed tumor cells with cerebriform nuclei into blast cells within 5 days; however, sézary cells were somewha ...19846611200
endocrine reactivity (t3, t4, cortisol) during cold exposure in preterm and full-term lambs.the endocrine reactivity to a short-term cold exposure (+ 4 degrees c during 1 h 30 min) was studied in 8 full-term (ft) and 12 preterm (pt) limousin x romanov lambs, obtained by oestrogen injections to the ewes; 4 pt animals died (ptd) during the observation period and 8 remained alive (pta). the plasma cortisol, t4 and t3 levels were lower in pt lambs (particularly in ptd for t4 and t3) during the first hours of life. moreover, rectal temperature decreased sharply between birth and 30 min post ...19836626631
midtrimester thyroidectomy in the ovine fetus.six lamb fetuses at 63-101 days gestation had thyroidectomy (thx) and were investigated at term for weights, radiologic study, serum thyroxine (t4), and thyroid-stimulating hormone concentrations (tsh), electron-microscopic lung examination, acid base, blood flow, eeg, and brain metabolism. compared to age-matched controls, body weight was significantly reduced (p less than .025). brain and lung weights were reduced but not significantly. brain weight as a percent of body weight was significantl ...19836646876
hypothyroidism and antibody production in immature male chickens.this study was conducted to determine if hypothyroidism has an effect on humoral immunity in immature male chickens. two week old single comb white leghorn male chicks were used as experimental animals. two experiments were conducted using different methods to induce hypothyroidism. in experiment 1, birds were surgically thyroidectomized (tx group) and in experiment 2, hypothyroidism was induced by supplementing the feed throughout the experiment with 0.1% propylthiouracil (ptu group). antibody ...19836674126
influence of methimazole on murine thyroiditis. evidence for immunosuppression in vivo.thionamide drugs are immunosuppressives in vitro. to examine this action in vivo, a/j mice were immunized with human thyroglobulin (htg) (0.5 mg intraperitoneal injections for 5 d) beginning on days 6, 24, and 43 with or without methimazole (m) (0.05%) and l-thyroxine (t4) (0.1 micrograms/ml to prevent thyroid hypertrophy) in their water supply. groups (n = 8) were killed on days 37, 42, and 59. spontaneous splenic igg-secreting cells determined by staphylococcus protein a-linked sheep erythrocy ...19846699171
the isolation of identical thyroxine containing amino acid sequences from bovine, ovine and porcine thyroglobulins.identical, thyroxine containing tryptic peptides have been isolated from digests of bovine, ovine and procine thyroglobulins. this 19 residue hormone containing sequence, nh2-asn-ile-phe-glu-t4-gln-val-asp-ala-gln-pro-leu-arg-pro-cys-glu-leu-g in-arg- cooh, is completely conserved across these three species, and it represents a principal site of thyroxine synthesis. hplc maps of tryptic digests of the thyroglobulins have been monitored at several wavelengths and suggest that, in each case, only ...19846704086
enhanced endocrine sensitivity in mouse mammary glands: hormonal requirements for induction and maintenance.this laboratory has previously shown that mammary epithelium from pregnant and parous mice are 5-7 times more sensitive in vitro to insulin, cortisol, and prl than tissue from virgins, with respect to lactose synthetase activity. in the present studies, virgin mice were treated for 2 weeks with either progesterone or a pituitary allograft to increase prl levels, and the mammary explants exhibited the same heightened sensitivity to all three hormones that was noted in pregnant animals. treatment ...19846745173
[haptoglobins, streptococcus agglutination and streptococcal infections].the haptoglobins in man and in mammals react with streptococci bearing the t4-antigen. hp 2-2 and hp 2-1 react with high titres like complete agglutinins while hp 1-1 acts like a blocking antibody. it is surprising to observe the similarity of the behaviour of the haptoglobins and of igg and igm. streptococci carrying hp 1-1 yield a positive coombs-test. the coombs-serum however, is an anti-human-haptoglobin-body from sheep. by means of supplements it has been possible to increase partly conside ...19826752004
properties of a surface antigen expressed on activated human thymus-derived lymphocytes.we have identified previously a quantitatively minor membrane protein (p28) with an apparent reduced m.w. of 28,000, which is biosynthetically labeled in activated human lymphocytes. rabbit antisera with activity directed against p28 (alpha-atc) were prepared and p28 was identified by immunoprecipitation in np-40 extracts of activated, extrinsically labeled lymphocytes. p28 was not expressed in appreciable amounts by unstimulated t cells, stimulated or unstimulated b cells, null cells, or adhere ...19826801123
the chediak-higashi gene in humans. iii. studies on the mechanisms of nk impairment.lymphocytes from six chediak-higashi (ch) patients were markedly depressed in their ability to lyse tumour cell targets in both 51cr release and single cell cytotoxicity assays. the frequency of lymphocytes bearing the okm1 marker and the frequency of t3+, t4+, t8+, ia+, mo1+, mo2+ and b1+ cells was normal among sheep erythrocyte rosetting (e+) and non-rosetting (e-) peripheral blood leucocytes analysed by flow cytofluorography. cells expressing the nk shared markers, okm1, mac-1, fcr, and the c ...19836839545
[determination of haptoglobin by agglutination with anti-hp on latex particles].human sera are able to agglutinate latex particles sensitized with antihaptoglobin serum produced from sheep. the agglutination depends on the haptoglobin types. similar to the agglutination of t4-streptococci the titer of hp 1-1 is very low and the titers of sera of the types hp 2-1 and hp 2-2 are 1:160 or higher.19836882404
effect of high ambient temperature (35 degrees), and feed intake on plasma t4 levels in sheep. 19827063508
protein metabolism in growing lambs given fresh ryegrass (lolium perenne)--clover (trifolium repens) pasture ad lib. 2. endocrine changes, glucose production, and their relationship to protein deposition and the partition of absorbed nutrients.1. glucose metabolism and changes in the concentrations of several hormones in jugular plasma were measured in growing lambs fed on fresh pasture ad lib. one group of lambs acted as control while the second received a continuous abomasal infusion supplying 44 g sodium caseinate+0.5 g l-methionine/d. 2. hormone concentrations were determined by radioimmunoassay procedures and glucose irreversible loss measured from continuous infusion of d-[u-14c]glucose. 3. protein infusion increased plasma conc ...19827066291
treatment of ovine cretinism in utero with 3,5-dimethyl-3'-isopropyl-l-thyronine.placental transfer of iodothyronines is minimal in most species. the nonhalogenated thyroid hormone analog 3,5-dimethyl-3'-isopropyl-l-thyronine (dimit) was administered to pregnant ewes to determine if this compound could prevent cretinism in the thyroidectomized fetal lamb. pharmacokinetic studies comparing [125i]t3 and [3h]dimit resulted in fetal-maternal ratios for [3h]dimit which were 5- to 10-fold higher than the ratios for [125i]t3, suggestive of preferential transport of dimit across the ...19827084108
retarded fetal brain development resulting from severe dietary iodine deficiency in sheep.sheep have been used to study the effect of dietary iodine deficiency on the development of the fetal brain. severe iodine deficiency caused reduction in fetal brain and body weights and in brain dna and protein from 70 days gestation to parturition. the lowered brain weight and brain dna at 70 days gestation indicates a reduced number of cells, probably due to slower neuroblast multiplication which normally occurs from 40-80 days in the sheep, and the reduction in dna and protein after 80 days ...19827133315
absorption and half-life of bovine, caprine and ovine igg1 in the newborn lamb. effect of experimental prematurity and endocrine factors.the influence of experimental prematurity and endocrine factors on the absorption and half-life of bovine igg1 was studied in newborn limousin x romanov lambs. six preterm and six full-term animals were bottle-fed with a common bovine colostrum pool during 32 h, whereas seven preterm and six full-term lambs were fed with the same bovine colostrum 2 h post-partum, a caprine colostrum 8 h after birth and an ovine colostrum 16 h post-partum. in the first group, the maximal plasma igg1 levels were n ...19827137854
plasma iodothyronine levels in lambs during the perinatal period: influence of thyrotropin injection.plasma thyroxine (t4) and triiodothyronine (t3) levels were measured in 7 pregnant ewes and their 9 chronically cannulated foetuses during the last 37 days of gestation and the first 5 days after parturition. the highest plasma t4 and t3 levels were measured in lambs during the hours following parturition. in 7 chronically cannulated 139-day old foetal lambs, the intravenous injection of ovine thyrotropin (otsh; 7 mu per foetus) induced a significantly more intense increase in plasma t4 and t3 l ...19827156497
growth and sexual maturation in ewes: the role of photoperiod, diet and temperature on growth rate and the control of prolactin, thyroxine and luteinizing hormone secretion.the relationship of photoperiod, temperature and diet on growth rate and serum concentrations of thyroxine (t4), prolactin (prl) and luteinizing hormone (lh) were studied in ewe lambs from 9 to 32 wk of age. lambs reared on a diet supplying 1.78 kcal/g net energy had higher (p less than .025) serum t4 concentrations and greater average daily gain (adg) than lambs fed a lower energy ration (1.5 kcal/g). long artificial photoperiod of 16 h of light neither improved adg nor altered t4 concentration ...19827161216
immunological aspects associated with suppression of hormone levels in rats infected with plerocercoids of spirometra mansonoides (cestoda).the effect of the plerocercoid larvae of spirometra mansonoides on hormone levels and the immune system of intact and hypophysectomized (hx) rats was studied. intact rats exhibited a decrease in serum growth hormone (gh) and thyroxine (t4) concentrations and a suppression of the humoral immune response 2 wk postinfection. at 4 and 9 wk postinfection, hormone concentrations and the humoral immune response returned to normal levels in the rats. when rats were infected with plerocercoids and then r ...19827175621
the kinetics of the thyroid hormones and the peripheral conversion rate of thyroxine to triiodothyronine in acute liver insufficiency under experimental conditions.the kinetics of triiodothyronine (t3) and thyroxine (t4) were studied in 20 ewes. ten were used as the control group, the other 10 received massive hepatic lesions induced by the ingestion of carbon tetrachloride. half of each group were i.v. injected with 125it3 or 125it4, following a plasma disappearance over 96 hours. the amount of hormone present in each plasma sample was determined by immunoextraction procedure. the data was adjusted to the open two-compartment model. the hepatic insufficie ...19817239425
functioning of the thyroid gland in sheep infected with trichostrongylus colubriformis.radioactive tracers were used to to study the kinetic behaviour of inorganic iodine (i) and thyroxine (t4) in sheep (1) uninfected and fed ad libitum, (2) infected with trichostronglylus colubriformis and fed ad libitum and (3) uninfected but pair-fed to the infected animals. plasma concentration and pool size of inorganic i were each significantly lower in groups 2 and 3 than in 1. irreversible loss of inorganic i in both groups 2 and 3 was significantly greater than in 1. the turnover rate of ...19817244386
hormonal status in the newborn lamb (cortisol, t3, t4). relationships to the birth weight and the length of gestation: effect of the litter size.the experiments reported involve 18 romanov lambs born spontaneously between 135 and 145 days of gestation. their birth weights ranged between 1.22 and 3.55 kg. the neonatal changes in plasma cortisol, triiodothyronine and thyroxine levels were observed from birth to 30 days postpartum, and related to the length of gestation and the birth weight. positive correlations were found between: (1) plasma t3 (2, 4, 8 h and 11 days after birth), t4 levels (4 h after birth) and the birth weight; (2) plas ...19817295840
[comparative radioisotope study of the thyroid in various species of agricultural animals].radioisotope functional investigations of the thyroid gland were carried out with weaned lambs and pigs. the 131i captation capacity of the thyroid gland was studied to characterize the inorganic phase of iodine exchange. the evaluation of the hormone producing function of the thyroid gland required the determination of the level of the protein-bound 131i (pb 131i), t3-binding capacity of the thyroxin-binding globulin (tbg) and the ratio of the t3-binding capacity of tbg and the free thyroxin (t ...19817331231
postnatal lung function in lambs after fetal hormone treatment. effects of gestational age.we previously found that a single dose of betamethasone in combination with thyroxine given by intramuscular injection to fetal sheep 48 h before preterm delivery at 128 d gestation improved postnatal lung function. we have now asked how the combination of 0.5 mg/kg betamethasone and 15 micrograms/kg t4 given by a single fetal intramuscular injection changes lung response 48 h after treatment at 121 and 135 d gestation. at 121 d gestation the fetal hormone treatment significantly improved postna ...19957551379
regulation of beta 1-adrenoceptors by glucocorticoids and thyroid hormones in fetal sheep.the effects of betamethasone alone or in combination with thyroxine (t4) on ovine fetal beta-adrenoceptors were investigated at the molecular level. ovine fetuses (126 days gestation; term = 150 days) were treated with a single ultrasound-guided intramuscular injection of 0.5 mg/kg betamethasone, betamethasone + 50 micrograms/kg t4, or saline. forty-eight h after injection, lambs were delivered by cesarean section and evaluated three h for postnatal adaptation. myocardial beta-adrenoceptor equil ...19957621909
the effects of thyroid hormones on oxygen and glucose metabolism in the sheep fetus during late gestation.1. the effects of thyroid hormones on fetal metabolism during late gestation were examined by measuring the rates of glucose and oxygen utilization rates in chronically catheterized sheep fetuses made hypothyroid by either fetal thyroidectomy (tx) or hypophysectomy (hx). the values were compared with those in intact fetuses and in thyroxine (t4)-treated tx and hx fetuses. 2. umbilical o2 uptake expressed on a weight-specific basis was reduced by 20-30% in the hypothyroid fetuses and was restored ...19957730983
fetal corticosteroid and t4 treatment effects on lung function of surfactant-treated preterm lambs.three groups of sheep fetuses at 125 or 126 d gestational age randomly received a single ultrasound-guided intramuscular injection of saline, 0.5 mg/kg betamethasone, or 0.5 mg/kg betamethasone plus 50 micrograms/kg thyroxine (t4). forty-eight hours later the fetuses were delivered, treated with a pulmonary surfactant preparation, and ventilated for 3 h. corticosteroids alone and in combination with t4 increased frc, compliance, and lung volumes, and decreased the protein leak into the airspace. ...19957812555
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