Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0231807 (exertional dyspnea)
 3,402 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the role of thyroid hormones in enhancing lung and brain maturation during the perinatal period is well established, the cellular mechanisms involved in these processes are incompletely understood. Hypothyroidism retards the development of fetal pulmonary insulin, neonatal pulmonary beta-adrenergic and neonatal brain insulin receptors. In this study, we investigated the effect of hypo- or hyperthyroidism on the development of neonatal brain and lung epidermal growth factor (EGF) receptors. The rabbit pups were rendered hypothyroid by adding 0.05% propylthiouracil to the drinking water starting at 23 days of gestation and thereafter. The neonatal hyperthyroid state was achieved by intramuscular administration of 100 micrograms/kg of synthroid to the rabbit doe on the 29th and 30th day of pregnancy. Neonatal plasma free thyroxine (T4) concentrations were quantitated by a radioimmunoassay. Brain and lung plasma membranes were isolated by differential centrifugation. EGF receptor characteristics were studied using 125I-EGF binding assays and Scatchard analysis. The plasma free T4 concentrations were 0.36 +/- (SEM) 0.02 (n = 6), p less than 0.01 (n = 7) and 1.76 +/- 0.1 (n = 6) ng/dl in the control, hypothyroid and hyperthyroid pups, respectively. The percent specific binding of 125I-EGF to 200 micrograms of brain plasma membrane (BPM) protein was significantly lower in the hypothyroid (0.62 +/- 0.03, n = 7, p less than 0.01), and higher in the thyroxine-treated (1.58 +/- 0.08, n = 6, p less than 0.01) group when compared to control (1.08 +/- 0.06, n = 6) animals. However, the percent specific binding of 125I-EGF to 100 micrograms of lung plasma membrane (LPM) protein was similar in all three groups (2.24 +/- 0.28, control; 2.01 +/- 0.5, hypothyroid, and 2.26 +/- 0.3, hyperthyroid). The number of EGF receptors per milligram of BPM protein (X 10(-10] were lower in the hypothyroid (2.24 +/- 0.03, n = 5) and higher in the hyperthyroid (6.6 +/- 0.02, n = 4) group when compared to control (4.4 +/- 0.05, n = 4) with no apparent difference in Kd. There was no difference in the number of EGF binding sites per milligram of LPM protein (X 10(-10] within the groups (6.6 +/- 0.8, n = 6, control; 7.9 +/- 0.4, n = 4, hypothyroid, and 7.3 +/- 0.3, n = 4, hyperthyroid). Presence of high affinity receptors for EGF in the neonatal brain as well as lung supports the hypothesis that EGF may play an important role in neonatal brain and lung maturation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Thyroid-dependent maturation of neonatal brain but not lung epidermal growth factor receptors. 299 70

We have recently demonstrated that intramuscular administration of triiodothyronine (T3) or thyroxine (T4) to the rabbit doe results in its transfer across the placenta. In this study we investigated the effect of maternally administered T3 upon the functional and morphologic fetal lung maturation. T3 (175 micrograms/kg) or the vehicle was injected intramuscularly into the New Zealand White rabbit does on days 25 and 26 of gestation. On day 27 of pregnancy, the does were killed and the fetuses were delivered. Maternal and fetal plasma T3, glucose and insulin and fetal plasma corticosteroid concentrations were determined. The functional pulmonary maturity was assessed by performing the pressure-volume hysteresis while morphologic maturity was established by histologic techniques. Enhanced functional as well as morphologic fetal lung maturation was observed in female as well as male fetuses in T3-treated animals. However, there was a significant increase in the fetal mortality after T3 treatment, and the duration of survival in the extrauterine environment on premature delivery was not prolonged.
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PMID:Transplacental stimulation of fetal lung maturation: effect of triiodothyronine in the female and male rabbit fetus. 365 23

Experimental evidence in animals and humans suggest that glucocorticoids enhance fetal pulmonary maturation. Mechanisms of glucocorticoid effects remain unclear; but apparently include up regulation of fetal pulmonary insulin and beta-adrenergic receptors. A role of Epidermal Growth Factor (EGF) in fetal lung maturation through plasma membrane bound receptors has been recently proposed. Betamethasone, 0.085 mg/kg, was administered on 25th and 26th day of gestation to the rabbit doe. Fetal pulmonary EGF receptor characteristics in male or female fetuses were studied on the 27th day of pregnancy. The percent specific binding of 125-I-EGF to lung plasma membranes (LPM) and the number of receptor sites per mg of LPM protein or DNA content were significantly higher in the glucocorticoid treated female as well as male fetuses when compared to the control pups, with no difference in the Kd. Presence of high affinity receptors for EGF and their up regulation by glucocorticoids support the hypothesis that EGF plays an important role in fetal lung maturation and that some of the beneficial effects of glucocorticoids in decreasing the incidence of HMD may be mediated through its interaction with EGF.
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PMID:Glucocorticoids increase pulmonary epidermal growth factor receptors in female and male fetal rabbit. 632 86

Increasing daily light exposure from 8 to 16 h increases average daily body weight gains of sheep and Holstein cattle but reduces gains of white-tailed doe fawns. Some of these effects on average daily gain in sheep are the result of increased gut fill and pelt weight. Increasing daily exposure to light increases feed intake when sheep or cattle are fed ad libitum. However, increased feed intake is not a prerequisite for the anabolic effects of long duration exposures to light because increased growth occurs in the animals given 16 h light:8 h dark (16L:8D) even when feed intake is restricted. The anabolic effects of increased duration photoperiods in sheep are independent of the gonads, whereas in cattle they are dependent on the gonads. Consistent increases in average daily gains of cattle in response to longer duration photoperiods have not always been achieved. The lack of consistency may be associated with sexual maturity or rate of fattening of the animal. For example, the stimulatory effects of 16L:8D photoperiods on live weight gain are not readily manifested in immature prepubertal heifers, but occur primarily during the peripubertal period. Short days are conducive to deposition of fat, which may account for the stimulatory effects of short days on live weight gain of white-tailed doe fawns and excessively fattened Holsteins. In contrast, long duration photoperiods stimulate protein accretion in cattle. The hormonal signals that mediate the anabolic effects of increasing exposure to light are not associated with change in insulin, thyroxine or growth hormone concentrations in the blood. Glucocorticoid concentrations in serum decrease with longer duration photoperiods which is consistent with an anabolic effect. Increasing daily light exposure to 16 h/d hastens the increase in concentrations of progesterone and testosterone in sera of peripubertal heifers and prepubertal bulls, respectively. Thus, change in secretion of reproductive hormones in the peripubertal period of cattle may be associated with the anabolic effects previously described and is consistent with gonad dependency. Prolactin concentrations in serum increase in sheep and cattle as duration of light exposure increases. But, there is no irrefutable proof that prolactin is responsible for the increased rates of gain or change in carcass composition associated with longer exposures to light. Thus, the hormonal mechanisms involved in photoperiod-induced alterations in growth remain to be established.
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PMID:The influence of photoperiod on body weight gain, body composition, nutrient intake and hormone secretion. 639 93

We report on clinical and metabolic studies of a newly delineated lipomatosis, characterised by an abnormal mediastinal and abdominal accumulation of fat, without obesity. The clinical features, which occurred in all the patients studied, are: Exertional dyspnoea due to a space-occupying mediastinal accumulation of fat, without evidence of cardiac or pulmonary disease. A pseudo-ascitic abdominal enlargement, due to intra- and retroperitoneal accumulation of fatty tissue. Insulin-independent diabetes mellitus. Type IV hyperlipidaemia and elevated levels of plasma uric acid were observed in four patients. Intra-abdominal lipomatous tissue, obtained during laparoscopy from four patients, demonstrated a reduced lipolytic response to beta-adrenergic stimulation. Thus, fat deposition in the abdominal and mediastinal areas could be causally related to defective lipid mobilization in lipomatocytes. Lipoprotein lipase activity in abdominal adipose tissue were normal in two patients (10.0 and 10.6 nmol/g/min) and markedly elevated in another two patients (37.3 and 49.9 nmol/g/min), as compared with controls (12.7 +/- 2.1 nmol/g/min). When expressed on per cell basis, LPL activity in lipomatous tissue was significantly higher than in control tissue (3.21 +/- 1.1 nmol/10(5) cell/min vs 0.92 +/- 0.16 nmol/10(5) cell/min). Lipoprotein fractionation did not demonstrate consistent modification of the serum lipoprotein pattern. HDL and HDL2 cholesterol values were reduced, even in patients with elevated LPL activity in adipose tissue.
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PMID:Mediastino-abdominal lipomatosis: deep accumulation of fat mimicking a respiratory disease and ascites. Clinical aspects and metabolic studies in vitro. 651 1

Coronary artery fistula arising from both the right coronary artery and the circumflex coronary artery is rare. A 28-year-old woman with non-insulin-dependent diabetes mellitus and end-stage renal disease who was on regular hemodialysis complained of recent progressive exertional dyspnea. Congestive heart failure was diagnosed during work-up for simultaneous kidney and pancreas transplantation. Bilateral coronary fistulas draining into the coronary sinus were found by coronary angiography and further characterized by multidetector computed tomography followed by 3D reconstruction preoperatively. The operation was performed smoothly without heart arrest.
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PMID:Applying preoperative multidetector computed tomography to bilateral coronary artery fistulas. 2072 55

This study examined the effects of goji berries dietary supplementation on the energetic metabolism of doe. Thirty days before artificial insemination, 75 New Zealand White does were assigned to three different diets: commercial standard diet (C) and supplemented with 1% (LG) and 3% (HG) of goji berries, respectively. Body conditions, hormones and metabolites were monitored until weaning. Body weight and BCS were higher in HG than C (p < 0.05). LG showed lower T3/T4 ratio and cortisol concentrations (p < 0.05) and tended to have lower indices of insulin resistances (p < 0.1) than HG. Compared to control, leptin was higher in HG at AI (p < 0.01) and in LG during lactation (p < 0.05). Two principal components were extracted by multivariate analysis describing the relationships between (1) non-esterified fatty acids, insulin and glucose levels, and (2) body conditions and leptin metabolism. The first component highlighted the energy deficit and the insulin resistance of the does during pregnancy and lactation. The second one showed that leptin, body weight and Body Condition Score (BCS) enhance as levels of goji berries in the diet increase. Thus, the effects of goji supplementation are dose-dependent: an improvement on energy metabolism was achieved with a low-dose while the highest dose could determine excessive fattening and insulin resistance in does.
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PMID:Impact of Goji Berries (Lycium barbarum) Supplementation on the Energy Homeostasis of Rabbit Does: Uni- and Multivariate Approach. 3314 90