scholarly journals Large carboxy-terminal parathyroid hormone (PTH) fragment with a relatively longer half-life than 1-84 PTH is secreted directly from the parathyroid gland in humans

2003 ◽  
pp. 301-306 ◽  
Author(s):  
H Yamashita ◽  
P Gao ◽  
T Cantor ◽  
T Futata ◽  
T Murakami ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Parathyroid Gland ◽  
Half Life ◽  
Contralateral Side ◽  
Study Group ◽  
Blood Samples ◽  
Glandular Secretion ◽  
Whole Pth ◽  
Ultrasonographic Guidance ◽  
Carboxy Terminal

OBJECTIVE: It was discovered that an immunoreactive large carboxy-terminal parathyroid hormone (PTH) fragment (large C-PTH), likely 7-84 PTH, is present in the circulation. However, very little is known about the production and metabolism of this large C-PTH. Combining a whole molecule PTH (whole PTH) immunoradiometric assay (IRMA) specifically for 1-84 PTH and an intact PTH (iPTH) IRMA for the sum of 1-84 PTH and large C-PTH, we were able to assess the circulating level of this large C-PTH as well as the glandular secretion and metabolism of this large C-PTH in primary hyperparathyroidism (pHPT). METHODS: This study consisted of two patient groups consisting of 77 pHPT patients with a single adenoma. Of these, 43 comprised the venous sampling study group and 70 comprised the intra-operative PTH study group. (Seven patients belonged only to the former group, 34 patients to only the latter group, and 36 patients to both groups.) Preoperatively, blood samples were drawn from the bilateral internal jugular vein by ultrasonographic guidance and from the peripheral vein (n=43). During surgery, blood samples were drawn after anesthesia (basal level), before excision (pre-excision level) of one enlarged parathyroid gland, and at 5, 10, and 15 min post-excision (n=70). RESULTS: There were 26 patients whose iPTH assay levels differed by more than 10% between the right and left internal jugular. In 24 of the 26 patients, the large C-PTH levels obtained from the adenoma side were significantly higher than those from the contralateral side (117+/-135 vs 43+/-33 pg/ml, P<0.001). The plasma whole PTH values decreased more rapidly than the iPTH values after parathyroidectomy (P<0.001). CONCLUSIONS: Our study has demonstrated that the large C-PTH, likely 7-84 PTH, is directly released from the parathyroid gland in humans. Since the half-life of 1-84 PTH is much shorter than large C-PTH, likely 7-84 PTH, it would be advantageous to use an assay that specifically measures 1-84 PTH for intra-operative monitoring of parathyroidectomy.

scholarly journals Feasibility of Extrapolating Randomly Taken Plasma Samples to Trough Levels for Therapeutic Drug Monitoring Purposes of Small Molecule Kinase Inhibitors

2021 ◽  
Vol 14 (2) ◽  
pp. 119
Author(s):  
Ruben A. G. van Eerden ◽  
Esther Oomen-de Hoop ◽  
Aad Noordam ◽  
Ron H. J. Mathijssen ◽  
Stijn L. W. Koolen
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Small Molecule ◽  
Trough Concentration ◽  
Drug Monitoring ◽  
Half Life ◽  
Kinase Inhibitors ◽  
Therapeutic Drug ◽  
Blood Samples ◽  
Elimination Half ◽  
Trough Levels

Small molecule kinase inhibitors (SMKIs) are widely used in oncology. Therapeutic drug monitoring (TDM) for SMKIs could reduce underexposure or overexposure. However, logistical issues such as timing of blood withdrawals hamper its implementation into clinical practice. Extrapolating a random concentration to a trough concentration using the elimination half-life could be a simple and easy way to overcome this problem. In our study plasma concentrations observed during 24 h blood sampling were used for extrapolation to trough levels. The objective was to demonstrate that extrapolation of randomly taken blood samples will lead to equivalent estimated trough samples compared to measured Cmin values. In total 2241 blood samples were analyzed. The estimated Ctrough levels of afatinib and sunitinib fulfilled the equivalence criteria if the samples were drawn after Tmax. The calculated Ctrough levels of erlotinib, imatinib and sorafenib met the equivalence criteria if they were taken, respectively, 12 h, 3 h and 10 h after drug intake. For regorafenib extrapolation was not feasible. In conclusion, extrapolation of randomly taken drug concentrations to a trough concentration using the mean elimination half-life is feasible for multiple SMKIs. Therefore, this simple method could positively contribute to the implementation of TDM in oncology.

Parathyroid hormone metabolism and its potential as a uremic toxin

1980 ◽  
Vol 239 (1) ◽  
pp. F1-F12 ◽  
Author(s):  
E. Slatopolsky ◽  
K. Martin ◽  
K. Hruska
Keyword(s):  
Renal Failure ◽  
Parathyroid Hormone ◽  
Chronic Renal Failure ◽  
Biological Effects ◽  
Uremic Toxin ◽  
Terminal Portion ◽  
Single Chain ◽  
Biochemical Alterations ◽  
Amino Terminal ◽  
Carboxy Terminal

Secondary hyperparathyroidism is a universal complication of chronic renal failure. It has been proposed that the markedly elevated levels of immunoreactive parathyroid hormone (i-PTH) in uremia may represent a “uremic toxin” responsible for many of the abnormalities of the uremic state. Plasma i-PTH consists of a mixture of intact hormone, a single-chain polypeptide of 84 amino acids, and smaller molecular weight hormonal fragments from both the carboxy- and amino-terminal portion of the PTH molecule. The hormonal fragments arise from metabolism of intact PTH by peripheral organs as well as from secretion of fragments from the parathyroid glands. The structural requirements for the known biological actions of PTH reside in the amino-terminal portion of the PTH molecule. Carboxy-terminal fragments, biologically inactive at least in terms of adenylate cyclase activation, hypercalcemia, or phosphaturia, depend on the kidney for their removal from plasma, and thus accumulate in the circulation in chronic renal failure. It is unknown at the present time if other biological effects of these carboxy-terminal fragments may contribute to some of the biochemical alterations observed in uremia. The most significant consequence of increased PTH levels in uremia is the development of bone disease characterized by osteitis fibrosa. In addition, it would appear that PTH plays an important role in some of the abnormal electroencephalographic patterns observed in uremia. This may be due to a potential role of PTH in increasing calcium content of brain. Parathyroid hormone also has been implicated as a pathogenetic factor in many other alterations present in uremia, i.e., peripheral neuropathy, carbohydrate intolerance, hyperlipidemia, and other alterations. Unfortunately, outstanding clinical research is lacking in this field and conclusive experimental data are practically nonexistent. Further studies are necessary if one is to accept the concept of PTH being a significant “uremic toxin.”

scholarly journals Influence of Pesticide on Biochemical and Hematological Parameters in Beninese Vegetable Farmers

2018 ◽  
Vol 9 (1) ◽  
pp. 65
Author(s):  
Lucie AYI-FANOU
Keyword(s):  
Blood Cell ◽  
Biochemical Parameters ◽  
Mean Corpuscular Volume ◽  
Hematological Parameters ◽  
Control Group ◽  
Study Group ◽  
Blood Samples ◽  
Vegetable Farmers ◽  
Insignificant Difference ◽  
Hematological And Biochemical Parameters

In several countries, a lot of researches have shown the toxicity of pesticides on farmers. Meanwhile, few of them have dealt with vegetable farmers in Benin. Therefore, this study has been carried out to assess the effects of pesticides on vegetable farmers’ health. This study is conducted on 30 vegetable farmers who used pesticides and 20 subjects as control group. Pesticides used by vegetable farmers and their risky behavior were investigated. Their blood samples were collected and some tests were performed for hematological and biochemical parameters. For the statistical analysis of the results, Student’s test was used. Our investigations revealed that vegetable farmers of Benin were exposed to different active ingredients of pesticides such as (Abamectin, Acetamiprid, Chlorpyriphos ethyl, Cyfluthrin, Cypermethrin, Emamectin benzoat, Flubendiamid, Lambdacyhalothrin, Mancozeb, Profenofos, Spinosad and Spirotétramate). The hematological parameters showed significant decrease in White blood cell (WBC), Red blood cell (RBC), Hemoglobin (HGB), Hematocrit (HTC), Mean Corpuscular Volume (MCV), Platelet (PLT) count among study group. The enzymatic activities of Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT) have significantly raised between vegetable farmers and the control group, while the serum concentration in urea and creatinine showed insignificant difference in the study group. These results suggest that pesticides have adverse effects on vegetable farmers of South of Benin.

Studies on the Biosynthesis of Rat Parathyroid Hormone and Proparathyroid Hormone: Adaptation of the Parathyroid Gland to Dietary Restriction of Calcium1

Endocrinology ◽  
1973 ◽  
Vol 93 (4) ◽  
pp. 915-924 ◽  
Author(s):  
LUKE L. H. CHU ◽  
RONAL R. MACGREGOR ◽  
CONSTANTINE S. ANAST ◽  
JAMES W. HAMILTON ◽  
DAVID V. COHN
Keyword(s):  
Parathyroid Hormone ◽  
Parathyroid Gland ◽  
Dietary Restriction

scholarly journals The retrospective study of 93 patients with transmigration of mandibular canine and a comparative analysis with a control group

2018 ◽  
Vol 41 (4) ◽  
pp. 390-396 ◽  
Author(s):  
Paweł Plakwicz ◽  
Joanna Abramczyk ◽  
Julita Wojtaszek-Lis ◽  
Jolanta Sajkowska ◽  
Barbara Warych ◽  
...  
Keyword(s):  
Contralateral Side ◽  
Permanent Teeth ◽  
Control Group ◽  
Study Group ◽  
Affected Side ◽  
Significant Difference ◽  
Mandibular Canine ◽  
And Control ◽  
Primary Canine

Summary Objectives The aim of this study was to evaluate characteristics of patients with unilateral transmigration of a mandibular canine in the largest study group presented until now. Materials and methods The study group consisted of 93 patients with unilateral transmigration of mandibular canine; the control group included 85 non-affected patients. Type of transmigration, status of deciduous and permanent canines, prevalence of missing teeth, class of occlusion, and space conditions were assessed to draw comparisons between groups. Results In this study, 64.5 per cent patients presented type 1 of transmigration; types 2, 3, 4, and 5 were present in, respectively, 23.7, 5.4, 4.3, and 2.1 per cent patients. There was a clear, statistically significant difference (P < 0.0001) between the mean crown and apex migration and angulation for the three groups of canines (transmigrated, contralateral, and control), whereas no differences were observed for the total number of permanent teeth present. In the study group, 73.1 per cent patients retained their primary canine on the affected side and 18.3 per cent on the contralateral side; in the control group, 22.3 per cent subjects had at least one primary canine. There was a statistically significant difference in the distribution of types of malocclusion between the study and the control groups. Conclusions Transmigration of mandibular canine was associated with the presence of retained primary canine on the affected side, higher mesial tilting of contralateral mandibular canine when compared to the canines in the control group. Additionally, higher prevalence of Angle’s Class I occlusion in patients with canine transmigration was recorded.

scholarly journals Low Serum IGF-1 in Boys with Recent Onset of Juvenile Idiopathic Arthritis

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Anna-Carin Lundell ◽  
Malin Erlandsson ◽  
Maria Bokarewa ◽  
Hille Liivamägi ◽  
Karin Uibo ◽  
...  
Keyword(s):  
Juvenile Idiopathic Arthritis ◽  
Disease Duration ◽  
Population Based ◽  
Study Group ◽  
Newly Diagnosed ◽  
Biological Mechanisms ◽  
Blood Samples ◽  
Recent Onset ◽  
Estonian Population ◽  
Age And Sex

Background. Liver-derived insulin-like growth factor-1 (IGF-1) contributes bone formation. Decreased IGF-1 levels are common in juvenile idiopathic arthritis (JIA), but whether IGF-1 is related to sex and differ during the pathogenic progress of JIA is unknown. Objective. The aim of this study was to examine IGF-1 levels in boys and girls with newly diagnosed JIA, with established JIA and in controls. Methods. The study group included 131 patients from the Estonian population-based prevalence JIA study. Blood samples were obtained from 27 boys and 38 girls with early JIA (≤1 month from the diagnosis), 29 boys and 36 girls with established JIA (mean disease duration 18 months), and from 47 age- and sex-matched controls. Results. IGF-1 levels in boys were significantly decreased in early JIA compared to male controls, while IGF-1 levels in girls were comparable between JIA and controls. In early JIA, IGF-1 levels were 12-fold lower in boys relative to girls. In controls, IGF-1 levels correlated with both age and height, while these correlations were lost in boys with early JIA. Conclusion. We report a sex-dependent deficiency in serum IGF-1 in boys with early JIA, which argues for sex-related differences in biological mechanisms involved in the disease pathogenesis.

Effect of Endotoxin on Kinetics of Antithrombin III

1979 ◽  
Author(s):  
H. Tanaka ◽  
N. Kobayashi ◽  
T. Takeuchi ◽  
M. Takada ◽  
T. Haekawa
Keyword(s):  
Half Life ◽  
Antithrombin Iii ◽  
Coagulation Factors ◽  
Synthesis Rate ◽  
Blood Samples ◽  
At Iii ◽  
Kinetics Of ◽  
Plasma Half Life

The kinetics of antithrombin III(AT III) in dogs were studied using I-125-labelled AT III and Se-75-methionine. As reported at the last meeting of ISH, the plasma half-life of AT III was 1.7±0.2 days in normal 5 control dogs. The double i.v. administration of 200 ug/ltg of endotoxin and the single i.v. administration of 1 mg/kg of endotoxin resulted in 30% decrease of plasma AT III, 60% decrease of coagulation Factors (I, II, V, VII, VIII, IX), the shortening of plasma half-life of AT III to 1.4 days and the increase of J3u values, suggesting increase of the synthesis rate of AT III. Then, the synthesis of AT III was studied directly using Se-75-methionine. After i.v. injection of Se-75-methionine, blood samples were obtained. One ml of sample plasma was incubated for 24 hrs with 1 ml of anti-AT III antiserum, which was produied in rabbits and the radioactivity of the precipitates were determined. About 80% of AT III was recovered in the precipitates by this method. The maximum radioactivity was obtained 18 hrs after injection of Se-75-methionine, and 0.27 % of total injected Se-75-methionine were utilized to the production of AT III.These results indicates that; 1. Endotoxin accelerates the metabolism of AT III. 2. The analysis of AT III production is possible using Se-75-methionine as a tracer.

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