An adenylate cyclase bioassay for parathyroid hormone: some clinical experiences

1985 ◽  
Vol 68 (3) ◽  
pp. 321-326 ◽  
Author(s):  
M. S. Seshadri ◽  
Y. L. Chan ◽  
M. R. Wilkinson ◽  
R. S. Mason ◽  
S. Posen

1. An adenylate cyclase bioassay for parathyroid hormone (PTH) was evaluated in peripheral sera of ten normal subjects, 15 patients with various types of hypoparathyroidism, nine patients with malignancy-associated hypercalcaemia and 60 patients with primary or secondary hyperparathyroidism. The lower limit of detectability was 150 pg/ml in terms of synthetic human PTH (1-34). 2. PTH-like bioactivity was not detected in normal subjects, in patients with surgical hypoparathyroidism, in patients with idiopathic hypoparathyroidism or in patients with malignancy-associated hypercalcaemia. Serum from one untreated pseudohypoparathyroid patient consistently contained PTH-like bioactivity. 3. Bioactivity was detected in sera from 50% of patients with primary or secondary hyperparathyroidism. In two patients with secondary hyperparathyroidism calcium infusions suppressed this activity within 5 min. 4. Both in primary and in secondary hyperparathyroidism there was a significant positive correlation between levels of PTH-like bioactivity, PTH immunoreactivity and the histological severity of the disease.

1978 ◽  
Vol 54 (4) ◽  
pp. 349-353 ◽  
Author(s):  
N. Nijs-De Wolf ◽  
N. De Nutte ◽  
H. Brauman ◽  
J. Corvilain

1. The parathyroid hormone-like biological activity of concentrated urine was measured by the increase of plasma calcium concentration after intravenous injection of the sample into chickens. 2. Urine was tested in hypoparathyroid patients, normal volunteer subjects, primary hyperparathyroid patients before and after surgery and patients with secondary hyperparathyroidism. 3. In primary and secondary hyperparathyroidism the biological activity was significantly higher than in urine from normal subjects, which was in turn significantly higher than the activity in the urine of hypoparathyroid patients. This bioactivity diminished after surgical removal of a hyperparathyroid adenoma. 4. Decreased activity after trypsinization indicated the peptidic nature of the hypercalcaemic substance.


1982 ◽  
Vol 62 (4) ◽  
pp. 381-387 ◽  
Author(s):  
I. G. Lewin ◽  
S. E. Papapoulos ◽  
G. N. Hendy ◽  
S. Tomlinson ◽  
J. L. H. O'riordan

1. The response to exogenous parathyroid hormone (PTH) was tested in normal subjects and patients with osteomalacia due to vitamin D deficiency; 200 MRC units of bovine PTH were administered intravenously. 2. The rise in plasma adenosine 3′:5′-cyclic monophosphate (cyclic AMP) and the increase in urinary excretion of cyclic AMP were reduced in the patients with vitamin D deficiency. After treatment with vitamin D the responses returned to normal. 3. It is suggested that this reversible resistance is due to the secondary hyperparathyroidism associated with vitamin D deficiency.


1976 ◽  
Vol 51 (2) ◽  
pp. 161-168 ◽  
Author(s):  
A. M. Parfitt

1. Previously published data obtained by magnesium infusion in man were found to conform to a Tm/glomerular filtration rate (GFR) model on the assumption of 80% diffusibility of plasma magnesium. The lower limit of Tm,Mg/GFR was 625 μmol/l. 2. Previously published data concerning the effect of cellulose phosphate on magnesium metabolism in normal subjects, patients with latent hypoparathyroidism and patients with primary hyperparathyroidism were found to conform to the same model, with the same lower limit for Tm,Mg/GFR for all three levels of parathyroid function. 3. The threshold for magnesium excretion is sharper with less ‘splay’ than for phosphate, but as for phosphate it is close to the normal blood concentration. 4. Because of the geometrical relationship between different methods of presentation of data, at a constant value for Tm,Mg/GFR changes in magnesium load or in GFR automatically produce changes in fractional magnesium clearance. This is the explanation for the increase in fractional magnesium clearance which occurs with diminishing renal function. 5. Renal conservation of magnesium is a passive consequence of the fall in plasma magnesium. There was no evidence of augmented tubular reabsorption of magnesium in response to magnesium deprivation in any of the three groups of subjects. 6. The tubular reabsorption of magnesium was not altered detectably by a moderate deficiency or excess of parathyroid hormone. Changes in parathyroid hormone secretion are probably not concerned in normal magnesium homeostasis.


2016 ◽  
Vol 11 (3) ◽  
Author(s):  
Hamid Nasri ◽  
Azar Baradaran

To found the association of high PTH levels with some indexes of malnutrition-inflammation complex syndrome (MICS), a study was carried out a group of maintenance hemodialysis patients(MHPs) consisting of nondiabetic and diabetic patients. Intact serum PTH (iPTH) and serum C-reactive protein(CRP), serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), serum cholesterol (chol)and serum triglyceride (Tg) were measured .Body mass index (BMI) was also calculated . Total patients were 36(f=15 m=21), consisting of 25 non-diabetic HD patients and 11 diabetic HD patients. The mean patient`s age was 44(17) years. The value of serum iPTH of total HD patients was 434455 (median:309)pg/nd, the value of serum iPTH of diabetic and nondiabetic-dialysis patients were 201277(median:41) and 537483(median:340)pg/ml respectively. In this study we found a near significant positive correlation of serum iPTH with serum CRP, a significant inverse correlation of serum iPTH with BMI and a near significant positive correlation of serum ALP with Logarithm of CRP, a significant positive correlation of serum phosphorus with serum CRP and also a significant inverse correlation of serum phosphorus with BMI were found. A near significant inverse correlation of serum cholestrol with serum phosphorus as well as a near significant inverse correlation of serum cholestrol with serum CRP were existed too. When patients with iPTH below than 200 pg/ml were deleted, the correlation of iPTH with CRP was positive (r =0.42, p =0.085) and when patients with iPTH more than 500pg/ml were deleted, this correlation was found to be negative(r = -0.42, p =0.047), means that a low iPTH values is an index of malnutrition while higher values is associated with inflammation, Further attention needs to better control of hyperphosphatemia and maintaining the iPTH levels 1.5 times of normal to avoid the sides effects of secondary hyperparathyroidism.


1963 ◽  
Vol 42 (3) ◽  
pp. 437-452 ◽  
Author(s):  
H. Daweke

Using the method of glucose-1-14C oxydation to 14CO2 on the rat epididymal adipose tissue, the insulin-like activities (ILA) in the serum have been compared before and after oral loading with glucose in normal subjects, in maturity-onset diabetics and in insulin-requiring diabetics. In maturity-onset diabetics mean fasting values were found to be 30% below normal while in insulin-requiring diabetics they were 85% above normal. In normal subjects there was observed, 30 minutes after glucose loading, a moderate increase in blood sugar together with an increase of ILA of 222% above the starting value; in maturity-onset diabetics the increase in ILA was only 106% while the blood sugar was markedly increased. After glucose loading in maturity-onset diabetics, the total amount of insulin detected during the period of the experiment was, on the average, only 45% of that found in normal subjects. In insulin requiring diabetics there was no increase but, on the contrary, a steady decrease of the ILA values, while the blood sugar excessively increased. In general ILA values were higher than those in maturity-onset diabetics. No difference in response was found between maturity-onset diabetics treated with diet alone and those treated with diet and oral hypoglycaemic drugs. In contrast to the absolute ILA values, the index of insulin reserve, is of value in assessing the functional capacity of the pancreas. This index decreases progressively with the severity of the disease and reaches a maximum of 54% of the normal in maturity-onset diabetics, which can satisfactorily be explained by pancreas insufficiency. Only in some cases of insulin-requiring diabetics was an insulin reserve still detectable. The biological inactivity of the insulin circulating in the blood can be deduced from the increased ILA-values, as compared with those found in maturity-onset diabetics. Obviously some of this insulin can be released by the addition of glucose. It is likely that, in addition to pancreatic insufficiency, insulin-binding or insulin-inactivating antibodies play a part in the pathogenesis of insulin-requiring diabetes.


1980 ◽  
Vol 93 (3) ◽  
pp. 339-345 ◽  
Author(s):  
Naokazu Nagata ◽  
Yuriko Ono ◽  
Narimichi Kimura

Abstract. The interaction between parathyroid hormone (PTH) and prostaglandin E1 (PGE1) in influencing cyclic AMP metabolism in rat renal cortical tissue was examined. PTH and PGE1 stimulated additively the adenylate cyclase activity in the homogenate of the tissue. Both PTH and PGE1 enhanced the level of cyclic AMP in the incubated renal cortical tissue, but the effect of their simultaneous addition did not exceed the effect induced by PTH alone. Cyclic AMP accumulated in the incubation medium by stimulation by PTH was decreased by the simultaneous addition of PGE1. When the tissue was pre-incubated for 30 min with 2 to 10 μg/ml of PGE1, the magnitude of the increase of cyclic AMP caused by PTH subsequently added was lessened. However, the response to PTH of adenylate cyclase preparation obtained from the homogenate of PGE1-pre-treated tissue was not decreased. When first PTH was added to the incubating renal cortical tissue, the subsequent addition of PGE1 accelerated the decrease of cyclic AMP content in the tissue and decreased the amount of cyclic AMP released from the tissue. The interaction of PTH and PGE1 on cyclic AMP metabolism in the renal cortical tissue was in contrast to that seen in newborn rat calvaria where PGE1 and PTH acted additively in enhancing the level of cyclic AMP.


Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1061
Author(s):  
Wajdy J. Al-Awaida ◽  
Baker Jawabrah Al Hourani ◽  
Samer Swedan ◽  
Refat Nimer ◽  
Foad Alzoughool ◽  
...  

The outbreak of coronavirus disease 2019 (COVID-19), by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has quickly developed into a worldwide pandemic. Mutations in the SARS-CoV-2 genome may affect various aspects of the disease including fatality ratio. In this study, 553,518 SARS-CoV-2 genome sequences isolated from patients from continents for the period 1 December 2020 to 15 March 2021 were comprehensively analyzed and a total of 82 mutations were identified concerning the reference sequence. In addition, associations between the mutations and the case fatality ratio (CFR), cases per million and deaths per million, were examined. The mutations having the highest frequencies among different continents were Spike_D614G and NSP12_P323L. Among the identified mutations, NSP2_T153M, NSP14_I42V and Spike_L18F mutations showed a positive correlation to CFR. While the NSP13_Y541C, NSP3_T73I and NSP3_Q180H mutations demonstrated a negative correlation to CFR. The Spike_D614G and NSP12_P323L mutations showed a positive correlation to deaths per million. The NSP3_T1198K, NS8_L84S and NSP12_A97V mutations showed a significant negative correlation to deaths per million. The NSP12_P323L and Spike_D614G mutations showed a positive correlation to the number of cases per million. In contrast, NS8_L84S and NSP12_A97V mutations showed a negative correlation to the number of cases per million. In addition, among the identified clades, none showed a significant correlation to CFR. The G, GR, GV, S clades showed a significant positive correlation to deaths per million. The GR and S clades showed a positive correlation to number of cases per million. The clades having the highest frequencies among continents were G, followed by GH and GR. These findings should be taken into consideration during epidemiological surveys of the virus and vaccine development.


2021 ◽  
pp. 030157422096341
Author(s):  
Smita Mangesh Choudhari ◽  
Sunita Shrivastav

Introduction: Altered nasorespiratory function leads to altered craniofacial growth. Thus, airway evaluation is important for preventive, interceptive, and corrective orthodontic treatment. The aim of this study was to evaluate and compare adenoids, the upper airway, the tongue, and mandibular dimensions using “predictors of difficult airways” in class II division 1 and class II division 2 cases with class I cases. Method: Sixty subjects of age 15 to 18 years were divided into 3 groups (group 1: class I cases; group 2: class II division 1 cases; and group 3: class II division 2 cases) based on cephalometric parameters, with 20 cases in each group. Cephalometric evaluation of adenoids and the nasopharyngeal airway was done using the Handelman–Osborne area method. Upper and lower airway evaluation was done using McNamara’s linear method. “Predictors of difficult airways” were used for evaluation of the airway, which included nasal competency, the Mallampati scale, mandibular length, mandibular protrusion, and the thyromental distance. Results: The present study found a significant positive correlation between the grades of nasal competency and percentage adenoid wall area, and a significant negative correlation between the grades of nasal competency and the upper airway. There was a significant positive correlation between the grades of nasal competency and mandibular length, and a significant positive correlation between the grades of mandibular protrusion and mandibular length. There was a significant positive correlation between the grades of the thyromental distance and mandibular length. Conclusion: It was concluded that the “predictors of difficult airways” would be helpful in early diagnosis and identification of potential risk factors that may cause “breathing disorders”–related malocclusions and later on increase the risk of developing OSA.


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