scholarly journals Primary hypothyroidism in dogs is associated with elevated GH release

2001 ◽  
Vol 168 (1) ◽  
pp. 59-66 ◽  
Author(s):  
WM Lee ◽  
M Diaz-Espineira ◽  
JA Mol ◽  
A Rijnberk ◽  
HS Kooistra

The pulsatile secretion patterns of GH were investigated in seven beagle bitches by collecting blood samples every 10 min for 6 h during euthyroidism and 1.5 years after induction of primary hypothyroidism. Hypothyroidism was induced by surgical removal of the thyroid gland and subsequent destruction of any remnant thyroid tissue by oral administration of sodium [(131)I]iodide. Some of the physical changes observed in the dogs with primary hypothyroidism mimicked those of acromegaly. During both euthyroidism and hypothyroidism GH was secreted in a pulsatile fashion. The mean (+/-s.e.m. ) basal plasma GH concentration was significantly higher (P=0.003) in the hypothyroid state (4.1+/-1.6 microg/l) than in the euthyroid state (1.2+/-0.4 microg/l). Likewise, the mean area under the curve (AUC) for GH above the zero-level during hypothyroidism (27.0+/-10.0 microg/lx6 h) was significantly higher (P=0.004) than that during euthyroidism (11.7+/-2.0 microg/l x 6 h). The mean AUC for GH above the baseline was significantly lower (P=0.008) during hypothyroidism (2.4+/-0.8 microg/l x 6 h) than during euthyroidism (4.5+/-1.8 microg/lx6 h), whereas there was no significant difference in GH pulse frequency. The mean plasma IGF-I level was significantly higher (P<0.01) in the hypothyroid state (169+/-45 microg/l) than in the euthyroid (97+/-15 microg/l). The results of this study demonstrate that primary hypothyroidism in dogs is associated with elevated basal GH secretion and less GH secreted in pulses. This elevated GH secretion has endocrine significance as illustrated by elevated plasma IGF-I levels and some physical changes mimicking acromegaly. It is discussed that the increased GH release in hypothyroid dogs may be the result of the absence of a response element for thyroid hormone within the canine pituitary GH gene and alterations in supra-pituitary regulation.

1974 ◽  
Vol 75 (3) ◽  
pp. 497-502
Author(s):  
Mayer B. Davidson ◽  
Roger M. Steele

ABSTRACT Since fructose is normally metabolized in diabetics and has recently been shown to stimulate GH secretion, it was used to assess GH responses in diabetics. Fourteen diabetics (9 on insulin) and 8 controls matched for weight were studied. Fructose, infused over 10 min, was compared to arginine, infused over 30 min, both at 0.5 g/kg. Samples were collected at 0, 30, 60, 90 and 120 min and GH responses assessed as area under the curve minus the fasting area. There was no significant difference between the GH responses in diabetics and controls to either agent. Responses to arginine and fructose were significantly correlated (r = 0.60, P < 0.01) in all subjects, but not related to therapy, duration of disease or fasting glucose (75–287 mg/100 ml) in the diabetics. Oral glucose blunted the GH response to fructose in 2 controls. It is concluded that 1) fructose can stimulate GH secretion in male diabetics; 2) however, fructose-stimulated GH responses are not increased in diabetes mellitus.


2003 ◽  
pp. 407-412 ◽  
Author(s):  
K Hanew

OBJECTIVE: The effects of human leptin fragment(126-140) on pituitary function in eight healthy, non-obese men were studied. METHODS AND DESIGN: The effects of the fragment on spontaneous secretion of pituitary hormones and endogenous leptin, as well as on GHRH-induced GH secretion were examined. RESULTS: After the administration of the fragment (50 microg i.v. for 150 min), the mean nadir value and 45 min value were significantly lower than that of the control study. Endogenous leptin levels did not decrease significantly following the administration of the leptin fragment. Other pituitary hormones were not affected by the fragment. The area under the curve of the GH response to GHRH(1-44)NH(2) (10 microg, i.v. from 0 to 75 min) was also significantly inhibited by the combined administration of the leptin fragment (100 microg i.v. from -30 to 75 min) (P<0.001). Three subjects were re-examined with larger doses of the leptin fragment (200-400 microg), and even greater GH suppression was observed. CONCLUSIONS: These results indicate that human leptin fragment(126-140) has an inhibitory role in GH secretion, since when administered exogenously this fragment significantly suppressed spontaneous and, in a dose-response manner, GHRH-induced GH secretion. Clear effects of the fragment on other pituitary hormones and an inhibitory effect on endogenous leptin secretion were not observed in this study.


QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
N M Welson ◽  
M M M Samy ◽  
A A Gaafar ◽  
T A Badran

Abstract Objective To evaluate the effect of pterygium surgery on corneal topography by comparing wave front analysis before and one month after the surgical treatment. Methodology Fifty eyes of forty-one patients were included in this study. Twenty five male and sixteen female patients seeking pterygium surgery were recruited from the Ophthalmology Department Outpatient Clinic in Sohag Teaching Hospital during the period from July 2017 to May 2018. All eyes underwent pterygium excision with conjunctival autograft. Results In this study we found a highly statistically significant improvement in the mean uncorrected visual acuity from 0.44±0.21SD preoperatively to 0.62±0.18SD postoperatively (p &lt; 0.001) and a highly statistically significant difference in the mean logMAR visual acuity as it was decreased from 0.43±0.28 SD preoperatively to 0.34±0.23 SD postoperatively (p &lt; 0.001). Also, there was a highly statistically significant improvement in mean of manifest refractive astigmatism from -4.08±3.28 SD preoperatively to -1.46±1.40 SD postoperatively (p &lt; 0.001). We also found a highly statistically significant improvement in the mean cycloplegic astigmatism from -4.00±3.01 SD preoperatively to -1.39±1.33 SD postoperatively (p &lt; 0.001) and also there was a highly statistically significant improvement in the mean topographic astigmatism from -5.17±4.08 SD preoperatively to -2.20±2.31 SD postoperatively (p &lt; 0.001). We also found a highly statistically significant improvement in the mean of ISV (Index of Surface Variance) from 76.22±36.86 SD preoperatively to 33.56±15.02 SD post operatively (p &lt; 0.001) and also there was a highly statistically significant improvement in the mean IHD (Index of Height Decentration) from 0.042±0.027SD pre-operatively to 0.023±0.036 SD post operatively. Conclusion There was a highly statistically significant difference in the mean logMAR visual acuity and a highly statistically significant improvement in the mean uncorrected visual acuity. A highly statistically significant improvement in both refractive and topographic astigmatism after one month of the surgery was noted also. Here were also a highly statistically significant improvement in ISV and IHD that indicate improvement after pterygium removal. Recommendations Patient with pterygium that inducing astigmatism will benefit from surgical removal of the pterygium.


2015 ◽  
Vol 1 (6) ◽  
pp. 270
Author(s):  
Audumbar Digambar Mali ◽  
Ritesh Bathe ◽  
Manojkumar Patil ◽  
Ashpak Tamboli

Simple, fast and reliable spectrophotometric methods were developed for determination of Levocetirizine in bulk and pharmaceutical dosage forms. The solutions of standard and the sample were prepared in methanol. The quantitative determination of the drug was carried out using the zero order derivative values measured at 230 nm and the area under the curve method values measured at 227-234 nm (n=2). Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of Levocetirizine using 5-25?g/ml (r=0.998 and r=0.999) for zero order and area under the curve spectrophotometric method. All the proposed methods have been extensively validated as per ICH guidelines. There was no significant difference between the performance of the proposed methods regarding the mean values and standard deviations. Developed spectrophotometric methods in this study are simple, accurate, precise and sensitive to assay of Levocetirizine in tablets.


1993 ◽  
Vol 129 (5) ◽  
pp. 399-408 ◽  
Author(s):  
Torben Laursen ◽  
Jens OL Jorgensen ◽  
Hans Ørskov ◽  
Jens Møller ◽  
Alan G Harris ◽  
...  

Animal studies have demonstrated that in addition to inhibiting growth hormone (GH) secretion octreotide inhibits in a direct manner hepatic or peripheral insulin-like growth factor I (IGF-I) generation. To test this hypothesis in humans we studied ten GH-deficient patients with frequent blood sampling during 38 h on two occasions. Regular GH therapy was discontinued 72 h prior to each study period. At the start of each study a subcutaneous (sc) injection of GH (3 IU/m2) was given (at 18.00 h). In a single-blinded crossover design, patients received a continuous sc infusion of either octerotide (200 μg/24 h) or placebo (saline). The pharmacokinetics of GH were similar on the two occasions. The area under the curve±sem of serum GH was 142.5±53.6 μg·l−1·h−1 (octreotide) and 144.8±41.8 μg·l−1·h−1 (placebo), (p=0.73); Cmax (μg/l) was 12.5±1.47 (octreotide) and 12.8±1.42 (placebo) (p=0.83), and Tmax (h) was 6.1±0.97 (octreotide) and 5.2±0.65 (placebo) (p=0.49). Growth hormone administration was associated with an increase in serum IGF-I (μg/l), which was identical during the two studies, from 85.3±19.4 to 174.25±30.3 for octreotide and from 97.0±26.4 to 158.8±28.2 for placebo. Mean IGF-I levels (μg/l) were 138.2±25.1 (octreotide) and 134.5±28.6 (placebo) (p=0.78). Similarly, the increase in IGF binding protein 3 (IGFBP-3) levels was identical. Mean IGFBP-3 levels (μg/l) were 2303±323 (octreotide) and 2200±361 (placebo) (p=0.25). Mean insulin levels were significantly lower during octreotide treatment (39.9±17.9 mU/l) than during placebo (59.7±17.8 mU/l) (p<0.05). Mean blood glucose levels were elevated significantly during octreotide infusion (5.98±0.23 mmol/l for octreotide and 5.07±0.16 mmol/l for placebo; p=0.001). Glucagon levels decreased non-significantly (p=0.07) and IGFBP-1 levels tended to increase during infusion of octreotide although not significantly (p=0.41). Levels of the lipid intermediates were identical on the two occasions. Alanine and lactate levels were significantly increased during octreotide infusion. Mean levels of blood alanine (μmol/l) were 470.8±24.2 (octreotide) and 360.1±17.8 (placebo) (p<0.02). Mean levels of blood lactate were 1038±81.0 (octreotide) and 894.4±73.8 (placebo) (p<0.04). We conclude that short-term continuous sc infusion of octreotide has no direct effect on the generation of IGF-I or the pharmacokinetics of exogenous GH in GH-deficient man.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Minghua Liu ◽  
Yanyan Hu ◽  
Guimei Li ◽  
Wenwen Hu

Objective. The follow-up of GH levels in short-stature children with pituitary hyperplasia secondary to primary hypothyroidism (PPH) is reported in a few cases. We aimed to observe changes in GH secretion in short-stature children with PPH. Methods. A total of 11 short-stature children with PPH accompanied by low GH levels were included. They received levothyroxine therapy after diagnosis. Their thyroid hormones, IGF-1, PRL, and pituitary height were measured at baseline and 3 months after therapy. GH stimulation tests were performed at baseline and after regression of thyroid hormones and pituitary. Results. At baseline, they had decreased GH peak and FT3 and FT4 levels and elevated TSH levels. Decreased IGF-1 levels were found in seven children. Elevated PRL levels and positive thyroid antibodies were found in 10 children. The mean pituitary height was 14.3±3.8 mm. After 3 months, FT3, FT4, and IGF-1 levels were significantly increased (all p<0.01), and values of TSH, PRL, and pituitary height were significantly decreased (all p<0.001). After 6 months, pituitary hyperplasia completely regressed. GH levels returned to normal in nine children and were still low in two children. Conclusion. GH secretion can be resolved in most short-stature children with PPH.


2014 ◽  
Vol 58 (7) ◽  
pp. 731-736 ◽  
Author(s):  
Raquel de Carvalho Abi-Abib ◽  
Mário Vaisman

Objective It is believed that gastric pH interferes in levothyroxine absorption. Omeprazole, which acts by blocking the secretion of gastric acid, might interfere in hypothyroidism control in patients using levothyroxine and this effect could be dose dependent. The present study aimed to investigate this possibility. Subjects and methods Twenty-one patients with primary hypothyroidism who had been using a stabilized levothyroxine dosage for at least one year were selected and randomly assigned to take omeprazole at the dosage of 40 mg or 20 mg per day. The mean levels of thyroid-stimulating hormone (TSH) before and 3 months after omeprazole usage were compared in the entire sample and in each group. Results Ten patients concluded the entire treatment protocol in the 20 mg group and nine patients in the 40 mg group. There was no significant difference in TSH levels before and 3 months after omeprazole treatment in the entire patient sample (median levels: 2.28 vs. 2.30 mU/L, respectively: p = 0.56). Analysis of each subgroup (20 and 40 mg) showed no significant variation in TSH levels before and 3 months after omeprazole treatment (median levels: 2.24 vs. 2.42 mU/L, p = 0.62, and 2.28 vs. 2.30 mU/L, p = 0.82, respectively). No significant difference in the absolute (p = 0.93) or relative (p = 0.87) delta were observed between the two subgroups. Conclusion Omeprazole in the dosage of 20 or 40 mg/day does not interfere in a clinically relevant manner in the treatment of patients with hypothyroidism that was previously under control.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gang Yu ◽  
Kai Sun ◽  
Chao Xu ◽  
Xing-Hua Shi ◽  
Chong Wu ◽  
...  

AbstractMachine-assisted pathological recognition has been focused on supervised learning (SL) that suffers from a significant annotation bottleneck. We propose a semi-supervised learning (SSL) method based on the mean teacher architecture using 13,111 whole slide images of colorectal cancer from 8803 subjects from 13 independent centers. SSL (~3150 labeled, ~40,950 unlabeled; ~6300 labeled, ~37,800 unlabeled patches) performs significantly better than the SL. No significant difference is found between SSL (~6300 labeled, ~37,800 unlabeled) and SL (~44,100 labeled) at patch-level diagnoses (area under the curve (AUC): 0.980 ± 0.014 vs. 0.987 ± 0.008, P value = 0.134) and patient-level diagnoses (AUC: 0.974 ± 0.013 vs. 0.980 ± 0.010, P value = 0.117), which is close to human pathologists (average AUC: 0.969). The evaluation on 15,000 lung and 294,912 lymph node images also confirm SSL can achieve similar performance as that of SL with massive annotations. SSL dramatically reduces the annotations, which has great potential to effectively build expert-level pathological artificial intelligence platforms in practice.


1997 ◽  
Vol 82 (7) ◽  
pp. 2166-2171
Author(s):  
Ayse Pinar Cemeroglu ◽  
Ariel L. Barkan ◽  
Gad B. Kletter ◽  
Inese Z. Beitins ◽  
Carol M. Foster

Acceleration of linear growth during puberty is associated with increased GH secretion, although the relationship between growth and GH is complex. As GH exists as a family of isoforms, some of which may not be identified by immunoassay, there may be alterations in isoform secretion during pubertal maturation that result in increased growth. The changes in serum immunoreactive and bioactive GH concentrations across pubertal maturation were determined in 30 boys, aged 6.5–19.3 yr, with idiopathic short stature or constitutional delay of adolescence. Data were grouped as follows: 1) 6 prepubertal boys with bone age 7 yr or less; 2) 5 prepubertal boys with bone age of more than 7 yr; 3) 10 boys in early puberty; 4) 9 boys with mid- to late puberty. Blood was obtained every 20 min from 2000–0800 h. An equal aliquot of each serum sample was pooled for determination of GH by bio- and immunoassays. The mean serum immunoreactive GH concentration increased from 2.1 ± 0.3, 1.8 ± 0.3, and 2.9 ± 0.5 μg/L in groups 1, 2, and 3, respectively, to a peak of 4.6 ± 0.7 μg/L in group 4 (P &lt; 0.05 vs. groups 1–3). The mean serum GH bioactivity was 48 ± 13 μg/L in group 1 and declined to 39 ± 8 and 31 ± 3 μg/L in groups 2 and 3, increasing to a maximum of 64 ± 15 μg/L in group 4 (P &lt; 0.05 vs. group 3). The ratio of bioactive to immunoreactive GH suggests that the biopotencies of secreted isoforms do not increase during pubertal maturation. The role of E2 in increasing GH secretion was characterized in 8 additional early pubertal boys. Each boy received a saline infusion from 1000–0800 h, followed 1 week later by an infusion of E2 at 4.6 nmol/m2·h. Blood was obtained every 15 min from 2200–0800 h for GH and LH and every 60 min for E2 and testosterone. An equal aliquot of each overnight serum sample was pooled for insulin-like growth factor I (IGF-I) and GH by immuno- and bioassays. The mean serum LH concentration decreased from 5.0 ± 0.9 to 2.3 ± 0.6 IU/L (P &lt; 0.01), and the E2 concentration increased from 22 ± 4 to 81 ± 26 pmol/L (P &lt; 0.01) during saline and E2 infusions, respectively. Mean serum GH concentrations as measured by immunoassay were similar during both infusions (6.6 ± 1.4 vs. 9.7 ± 2.1 μg/L; saline vs. E2 infusion, respectively). In contrast, the mean serum GH concentration, as measured by bioassay, decreased from 48 ± 10 μg/L during saline infusion to 16± 3 μg/L during E2 infusion (P &lt; 0.05). The mean serum IGF-I concentration also decreased significantly from 116 ± 17 to 93 ± 15 μg/L (saline vs. E2 infusion, respectively; P &lt; 0.05). Thus, although mean overnight serum GH concentrations increase in late puberty, whether measured by immuno- or bioassay, an acute increase in E2 produces an acute decline in serum GH bioactivity and a lesser decline in the serum IGF-I concentration. These unexpected changes indicate that E2 may affect pubertal growth and GH secretion in a complex or biphasic manner depending on the context in which it is administered.


2000 ◽  
Vol 18 (9) ◽  
pp. 1837-1844 ◽  
Author(s):  
U. Tidefelt ◽  
J. Liliemark ◽  
A. Gruber ◽  
E. Liliemark ◽  
B. Sundman-Engberg ◽  
...  

PURPOSE: The aim of the present study was to evaluate the effect of the cyclosporine derivative valspodar (PSC 833; Amdray, Novartis Pharma, Basel, Switzerland) on the concentration of daunorubicin (dnr) in leukemic blast cells in vivo during treatment.PATIENTS AND METHODS: Ten patients with acute myeloid leukemia (AML) were included. Leukemic cells from seven of the patients were P-glycoprotein (Pgp)–positive. dnr 100 mg/m2was given as a continuous infusion over 72 hours. After 24 hours, a loading dose of valspodar was given, followed by a 36-hour infusion of 10 mg/kg per 24 hours. Blood samples were drawn at regular intervals, and concentrations of dnr and its main metabolite, daunorubicinol, in plasma and isolated leukemic cells were determined by high-pressure liquid chromatography.RESULTS: The mean dnr concentrations in leukemic cells 24 hours after the start of infusion (before valspodar) were 18.8 μmol/L in Pgp-negative samples and 13.5 μmol/L in Pgp-positive samples. After 8 hours of valspodar infusion, these values were 25.8 and 24.0 μmol/L, respectively. The effect of valspodar was evaluated from the ratio of the area under the curve (AUC) for dnr concentration versus time in leukemic cells to the AUC for dnr concentration against time in the plasma. For the seven patients with Pgp-positive leukemia, the mean ratio increased by 52%, from 545 on day 1 to 830 on day 2 (P < .05) when valspodar was given. In the three patients with Pgp-negative leukemia, no significant difference was observed.CONCLUSION: These results strongly suggest that valspodar, by interacting with Pgp, can increase the cellular uptake of dnr in leukemic blasts in vivo.


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