Post Thyroidectomy Assessment of Intact Parathyroid Hormone for Early Prediction of Hypocalcaemia

Background: As the half-life of intact parathyroid hormone (iPTH) is very low, it reflects parathyroid insufficiency within minutes to hours after total thyroidectomy. Therefore, iPTH level assessment in the postoperative period can be used to predict the development of hypocalcaemia. The optimal time point to measure serum iPTH is important for the accurate prediction of hypocalcaemia. Aim: This paper aims to evaluate the ability of iPTH as an early predictive marker of hypocalcaemia and determine which time iPTH is more able to predict postoperative hypocalcaemia. Method: This prospective observational study was conducted in the Department of Otolaryngology-Head & Neck Surgery, BSMMU, Dhaka, from July 2020 to December 2021, with 67 patients who underwent total thyroidectomy. iPTH levels were measured on the day before the operation and at 1 hour, 4 hours, and 24 hours after the operation. S.calcium levels were measured on the day before the operation and 1st postoperative day. All the data were compiled and sorted properly and were analyzed statistically. Results: Postoperative hypocalcaemia developed in 18 cases, with an incidence of 26.9%. Pearson correlation showed a significant correlation between postoperative iPTH at 1 hr, 4 h, and 24 hr with 1st postoperative calcium value. The Receiver operating characteristic (ROC) curve was processed for the postoperative iPTH at 1 hr, 4 h, and 24 hr. The sensitivity, specificity, cut-off value, and mean AUC found 93.9%, 94.4%, ≤14.0, 0.988;95.9%, 94.4%, ≤09.5, 0.993 and 91.8%, 94.4%, ≤11.0, 0.993 respectively. Conclusion: iPTH can be used as an early predictor of post-thy-roidectomy hypocalcaemia. 4 hr iPTH showed more sensitivity and specificity for a cut-off value near the laboratory reference range.

Vitamin D, Parathyroid Hormone, Insulin Sensitivity and Islet β-Cell Secretory Function in Diabetic Patients from South Kivu in the Democratic Republic of Congo: Cross-Sectional Study

Background: The role of vitamin D and parathyroid hormone in the metabolic profile of type 2 diabetes mellitus in sub-Saharan Africa has not been adequately assessed. The aim of this study was to determine the prevalence of low vitamin D level and secondary hyperparathyroidism and their association with insulin sensitivity and β-cell secretory function among Congolese type 2 diabetics. Methodology: Fasting glycaemia, fasting insulin, 25OH D3 and human parathyroid hormone (hPTH) were measured in one hundred and eighty-four type 2 diabetic patients followed as outpatients in South Kivu. Levels of 25OH D3 65 pg/ml defined low vitamin D and elevated parathyroid hormone levels, respectively. The HOMA model was used to measure insulin sensitivity and β-cell secretory function. Results: Medians (IQR) were 25.3 (20.4 - 32.4) ng/ml for 25OH D3 and 53.7 (38.4 - 115.7) pg/ml for hPTH. 58.7% of diabetics had insulin resistance, 126 (68.5%) had low vitamin D and 80 (43.5%) had hyperparathyroidism. In multivariate analysis, hPTH (partial r = −0.28;p = 0.0002) and 25OH D3 (partial r = 0.16;p = 0.03) showed an independent association with insulin sensitivity after adjustment for body mass index and waist circumference. Finally, hPTH (partial r = 0.27;p = 0.0002) was the sole determinant of β-cell secretory function. Conclusions: This study confirms the high prevalence of low vitamin D level and secondary hyperparathyroidism and their association with insulin resistance and impaired islet β-cell secretory function among Congolese with type 2 diabetes mellitus. Vitamin D and calcium supplementation should be envisaged for cases of deficiency in this region.

N-acetylcysteine and zinc sulphate abate di-2-ethylhexyl phthalate-mediated reproductive dysfunction in rats:Focus on oxidative and sex hormone receptors mechanisms

Objective:To investigate the potential of N-acetylcysteine(NAC)and zinc sulphate(ZnSO_(4))in mitigating reproductive dysfunction caused by di-2-ethylhexyl phthalate(DEHP)in rats and to understand the underlying mechanisms,specifically oxidative stress and sex hormone receptor activity.Methods:Thirty-five male Wistar rats were randomly divided into five equal groups(n=7 per group).Group 1 was administered 0.5 mL of distilled water and served as the control group.Group 2 was given only DEHP(750 mg/kg/day),while group 3,4 and 5 were given DEHP(750 mg/kg/day)plus NAC(100 mg/kg/day),DEHP(750 mg/kg/day)plus ZnSO_(4)(0.5 mg/kg/day),and DEHP(750 mg/kg/day)plus NAC(100 mg/kg/day)as well as ZnSO_(4)(0.5 mg/kg/day),respectively.All treatments lasted for 21 days.Samples were obtained after the rats were sacrificed,and hormones levels in the serum and markers of oxidative stress in the testicles were analyzed using the enzyme-linked immunosorbent assay.The amount of androgen receptors in the testicles was determined by immunohistochemistry,and the susceptibility of testosterone and DEHP to bind to androgen receptor and 5α-reductase was determined by molecular docking studies.Results:DEHP decreased reproductive hormones,testicular antioxidant enzymes,increased malondialdehyde levels,and negatively impacted histology of the pituitary and testes.NAC or ZnSO_(4) treatment showed a marked improvement in testicular antioxidant status and hormone levels,as well as a positive effect on the histology of the pituitary and testes.The combination of both treatments appeared to be more effective.The affinity of DEHP to bind to androgen receptors may lead to disruption of androgen receptor signaling,which can further result in dysfunction of hormones related to androgen.However,NAC is more likely to form stronger binding interactions with follicle stimulating hormone and luteinizing hormone receptors,as well as gonadotropin-releasing hormone receptors,when compared to DEHP.Conclusions:The possibility that NAC and ZnSO_(4) could downregulate DEHP-induced sex hormone changes is suggested by their potential to reduce toxicity.

Thyroid hormones and thyroid hormone receptors: Effects of thyromimetics on reverse cholesterol transport

Reverse cholesterol transport (RCT) is a complex process which transfers cholesterol from peripheral cells to the liver for subsequent elimination from the body via feces. Thyroid hormones (THs) affect growth, develop- ment, and metabolism in almost all tissues. THs exert their actions by binding to thyroid hormone receptors (TRs). There are two major subtypes of TRs, TRα and TRβ, and several isoforms (e.g. TRα1, TRα2, TRβ1, and TRβ2). Activation of TRα1 affects heart rate, whereas activation of TRβ1 has positive effects on lipid and lipoprotein metabolism. Consequently, particular interest has been focused on the development of thyromimetic compounds targeting TRβ1, not only because of their ability to lower plasma cholesterol but also due their ability to stimulate RCT, at least in pre-clinical models. In this review we focus on THs, TRs, and on the effects of TRβ1-modulating thyromimetics on RCT in various animal models and in humans.

The Effect of Administration of Rutin on Plasma Levels of Estrogen, Prolactin, Growth Hormone and Gene Expression of Their Receptors in Mammary Glands in Ovariectomized Rats

The development of mammary glands, endocrine hormone concentrations and the gene expression of related receptors were measured in ovariectomized virgin rats after adminstration of an estrogen-like plant extract, rutin. Thirty-two ovariectomized virgin Wistar rats were randomly assigned to 4 treatments with 8 animals each： gastric infusion of 2 mL normal saline per unovariectomized rat per day （Sham）, gastric infusion of 2 mL normal saline per ovariectomized rat per day （Ova）, gastric infusion of 60 mg rutin kg-1 body weight （BW） per ovariectomized rat per day （Ova＋Rut）, or intramuscular injection of 60 ug estradiol kg-1 BW per ovariectomized rat weekly （Ova＋Est）. Samples of blood and mammary glands were harvested to determine the levels of estrogen （E2）, prolactin （PRL） and growth hormone （GH）, and the gene expression of estrogen receptors （ER）, prolactin receptors （PRLR） and growth hormone receptors （GHR） with radioimmunoassy （RIA） and RT-PCR technology, respectively. The E2 concentration in plasma and gland tissues from the rats of Ovx＋Rut or Ovx＋Est was higher than that of Ovx （P〈0.05）, but the plasma E2 concentration from the rats of Ovx＋Rut was lower than that of Sham （P〈0.05）. The order of the PRL concentration in plasma and gland tissues was Ovx〈Ovx＋Rut〈Ovx＋Est 〈Sham, and the difference in each treatment （P〈0.05）. The plasma GH concentration was lower in Ovx than in Ovx＋Rut or Ovx＋Est, and lower in Ovx＋Rut than in Sham （P〈0.05）. The GH concentration in gland tissues was lower in Ovx than in Ovx＋Rut or Ovx＋Est （P〈0.05）, and lower in Ovx＋Rut than in Sham （P〈0.05）. The gene expression of ER in gland tissues was increased in an order as Ovx〈Ovx＋Rut〈Ovx＋Est〈Sham （P〈0.05）, and PRLR, GHR showed the same trend. In conclusion, adminstration of rutin increased the E2 concentration in plasma and mammary glands, promoted pituitary PRL and GH release, up-regulated the gene expression of ER, PRLR and GHR, and stimulated mammary development in ovariectomized virgin rats.

Safety,Tolerability and Pharmacokinetic Study of Recombinant Human Parathyroid Hormone [rhPTH(1-84)] in Chinese Healthy Volunteers

The current study was designed to determine the safety, tolerability and pharmacokinetic parameters of recombinant human parathyroid hormone [rhPTH （1-84）] used for the treatment of osteoporosis. In the single-dose format pharmacokinetic study, thirty-six healthy male volunteers received three dose levels of rhPTH （1-84） subcutaneously： 1, 2, and 4 μg/kg. The blood was timing drawn and the serum concentration of rhPTH （1-84） was determined by enzyme linked immunosorbent assay （ELISA）. Serum concentration-time curves of PTH （1-84） exhibited a double-peak pattern, the first peak appearing about 10 to 30 min after administration and the second peak occurring about 1.5 to2 h after administration. Serum terminal half-time of PTH （1-84） was approximately 2 h. The parameters indicated the serum levels were directly proportional to the administered dose, with the mean Cmax and AUC0_24 ranging from approximately 543.47 to 1845 pg/mL and 2358.6 to 9232.12 pg.h.mL^-1 over the dose range. The drug was well tolerated, the clinical symptoms were generally mild and of short duration.

Effect of neoadjuvant chemotherapy on the expression of hormone receptors and Ki67 in Chinese breast cancer patients:A retrospective study of 525 patients

This study was designed to investigate the effect of neoadjuvant chemotherapy on the expression of hormone receptors and Ki67 in Chinese female breast cancer patients. The expression of estrogen receptor（ER）, progesterone receptor（PR） and Ki67 among 525 neoadjuvant chemotherapy cases was studied by immunohistochemistry.Differences between specimens made through preoperative core needle biopsy and excised tissue biopsy were observed. The positive rates of ER, PR and Ki67 in core needle biopsy and excised tissue biopsy were 65.3% and 63.2%, 51.0% and 42.6%, 65.6% and 43.4%, respectively. The expression of ER, PR and Ki67 in core needle biopsy and excised tissue biopsy had no statistically significant difference. However, after neoadjuvant chemotherapy, the discordance rates of ER, PR and Ki67 were 15.2%（79/521）, 26.9%（140/520） and 44.8%（225/502）, respectively. The ER, PR and Ki67 status changed from positive to negative in 7.5%（39/521）, 13.3%（69/520） and 21.1%（106/502） of the patients, whereas ER, PR and Ki67 status changed from negative to positive in 7.7%（40/521）, 13.6%（71/520）and 23.7%（119/502） of the patients, respectively. These results showed that the status of some biomarkers changes after neoadjuvant chemotherapy and biomarker status needs to be reexamined to optimize adjuvant systemic therapy and better prognosis assessment.

Assessment of Endometrial Carcinoma Markers and Hormone Receptors Profile before and after Bariatric Surgery: A Clinico-Pathological-Immunohistochemical Study

Background: Obesity is a major risk factor for endometrial carcinoma, and we aim to assess markers of carcinogenesis including PTEN and Ki-67 and hormone receptors profile including ER, PR and AR before and after bariatric surgery to find out its effects in reducing endometrial carcinoma risk in morbid obese females. Patients and methods: The study included 80 females with morbid obesity (BMI > 40 Kg/m2) who underwent bariatric surgery. All were sampled by Pipelle biopsy at baseline and 12 months after operation and examined histopathologically and immunohistochemically for Ki-67, PTEN, ER, PR and AR. Results: Sixty two out of 80 (62/80) females showed no pathological abnormalities;4 had polyps;7 had simple endometrial hyperplasia;4 had atypical endometrial hyperplasia and 3 had endometrial carcinoma. In total, 34 females underwent gastric bypass operation (42.5%) and 46 underwent a sleeve gastrectomy operation (57.5%). There was a statistically significant difference between baseline weight and BMI before and after surgery (p < 0.001). Of the 7 women with simple hyperplasia, resolution occurred in 5 within 7 months of surgery. Three of 4 females with atypical hyperplasia (AH) showed resolution after 9 months. Mean Ki-67 score was lower at 12 months (p < 0.001) after surgery. 43/77 (55.8%) baseline biopsies were glandular PTEN null, including 9/15 of the women with baseline endometrial abnormalities, of whom 5/15 regained glandular PTEN expression as their endometrial abnormalities resolved. There was a significant reduction in ER score after surgery (p < 0.001). PR H-scores were not significantly different post-operatively (p = 0.193). AR H-scores were higher significantly in pre-operative biopsies than post-operative ones (p < 0.001). Conclusion: Females with morbid obesity have a higher risk of harboring endometrial abnormalities even if asymptomatic. However, the endometrial pathology and the high ER and PR expression can be normalized within one year without medical treatment, signifying the role of bariatric surgery-induced weight loss in reducing the risk of endometrial neoplasia development. Also, the marked weight loss occurring after bariatric surgery induces highly significant endometrial change as resolution of atypical hyperplasia, and molecular changes as reduction of Ki-67 and restoration of PTEN that are associated with transition of endometrium from high to low risk.

Hypoxia-inducible factor-1a restricts the anabolic actions of parathyroid hormone

The hypoxia inducible factors （Hifs） are evolutionarily conserved transcriptional factors that control homeostatic responses to low oxygen. In developing bone, Hif-1 generated signals induce angiogenesis necessary for osteoblast specification, but in mature bone, loss of Hif-1 in osteoblasts resulted in a more rapid accumulation of bone. These findings suggested that Hif-1 exerts distinct developmental functions and acts as a negative regulator of bone formation. To investigate the function of Hif-1a in osteoanabolic signaling, we assessed the effect of Hif-1a loss-of-function on bone formation in response to intermittent parathyroid hormone （PTH）. Mice lacking Hif-1a in osteoblasts and osteocytes form more bone in response to PTH, likely through a larger increase in osteoblast activity and increased sensitivity to the hormone. Consistent with this effect, exposure of primary mouse osteoblasts to PTH resulted in the rapid induction of Hif-1a protein levels via a post-transcriptional mechanism. The enhanced anabolic response appears to result from the removal of Hif-1a-mediated suppression of β-catenin transcriptional activity. Together, these data indicate that Hif-1a functions in the mature skeleton to restrict osteoanabolic signaling. The availability of pharmacological agents that reduce Hif-1a function suggests the value in further exploration of this pathway to optimize the therapeutic benefits of PTH.

CORRELATION OF STEROID HORMONE RECEPTORS AND CLINICAL PATHOLOGICAL FEATURES WITH PROGNOSIS OF HUMAN BREAST CANCER

Clinical, pathological features and steroid hormone receptors (SR) including receptors of estrogen (ER), progesterone (PR) and androgen (AR) were observed in 58 cases of breast carcinoma, and related to patient 5- year survival rate through stratification and multivariatc analysis. The results showed that histologic tumor type and grading, lymphnode status, ER value and patient age took more important role in patient survival, and SR, especially, conferred survival advantage in advanced cases with tumor size larger than 2 cm, node involved, or TNM Stage Ⅱ-Ⅲ.

Molecular Characterization of Thyroid Hormone Receptors (TRs) and their Responsiveness to T3 in Microhylafissipes

To explore and enrich the molecular mechanisms of thyroid hormone receptors （TRs） in the metamorphosis of amphibians, the cDNA sequences of TRa and TRβ in Microhyla fissipes were cloned and characterized. TRa was 1 706 bp in length with an open reading frame （ORF） of 1 257 bp encoding a predicted protein of 418 amino acids and TRβ was 1 422 bp with an ORF of 1 122 bp encoding a predicted protein of 373 amino acids. Their protein sequences contained 4 conserved domains of the nuclear receptor superfamily with two highly conserved cysteine-rich zinc fingers in the DNA-binding domain, whereas TRβ was 42 amino acids shorter in its A/B domain than TRot. Highly-conserved sequences and structures indicated their conserved functions during metamorphosis. TRa expression reached peak at 12 h and then decreased from 12 h to 48 h. While dramatically up-regulated TRβ was observed after exposure of T3 within 24 h, and it was down-regulated from 24 h to 48 h. The expression pattern of TRβ is similar to that in the natural metamorphosis. Furthermore, tadpoles treated 24 h also resembled the climax of metamorphosis tadpoles and TRβ expression had higher responsiveness than TRa to T3 in M. fissipes. These results suggest M. fissipes may serve as the model to assay environmental compounds on TH signaling disruption.

Comparison between recombinant human parathyroid hormone(1-34) and elcatonin in treatment of primary osteoporosis

Objective:To evaluate the efficacy and safety of rhPTH(1-34) vs.elcatonin.Methods:Sixty palients with primary OP were randomly divided into two groups according to the ratio of 3:1.rhPTH(1-34) group(PTH group) was treated with subcutaneous injection of rhPTH(1-34) 20 μg daily for 18 months,and the elcalonin group(CT group) was treated with intramuscular injection of elcatonin 20 U weekly for 12 months.Bone mineral density(BMD) of the lumbar spine 2-4(L_(2-4))and femoral neck,serum calcium and phosphorus,urinary calcium,serum hone specific alkaline phosphatase(BSAP).and urinary c-terminal telopeptides of type Ⅰ collagen/creatinine(uCTX-Ⅰ /Cn were tested at baseline,and 6.12.and 18 months after treatment.Results:In PTH group.HMD of L_(2-4),at 6,12.and 18 months,BDM of Femoral neck at 18 month,BSAP at 6 and 12 months and uCTX- Ⅰ /Cr at 6.12 and 18 months were all significantly raised.In CT group.HMD of L_(2-4) at12 month and that of femoral neck at 12 and 18 months were significantly elevated,while HSAP was significantly decreased at 12 and 18 months,and no significant difference on CTX- Ⅰ /Cr was observed.When BMD growth and growth rate between two groups were compared.PTH group had better improvement in L_(2-4) BMD and growth rate than CT group at 6.12.and 18 months.BMD growth and growth rale of femoral neck al 12 month and its growth at 18 month in CT group were higher than in PTH group,hut there was no significant difference between two groups regarding the growth rates at 18 month.Besides,there were no significant differences regarding the rales ol adverse reactions between two groups.Conclusions:rhPTH(1—34),is safe and effective in the treatment of primary OP.It is superior to elcatonin in improving vertebral HMD at onset time,growth rate and growth range,but inferior to elcatonin at HMD of femoral neck.

Osteoporotic fracture and parathyroid hormone

Osteoporosis and age-related bone loss is associated with changes in bone remodeling characterized by decreased bone formation relative to bone resorption,resulting in bone fragility and increased risk of fractures.Stimulating the function of bone-forming osteoblasts,is the preferred pharmacological intervention for osteoporosis.Recombinant parathyroid hormone(PTH),PTH(1-34),is an anabolic agent with proven benefits to bone strength and has been characterized as a potential therapy for skeletal repair.In spite of PTH’s clinical use,safety is a major consideration for long-term treatment.Studies have demonstrated that intermittent PTH treatment enhances and accelerates the skeletal repair process via a number of mechanisms.Recent research into the molecular mechanism of PTH action on bone tissue has led to the development of PTH analogs to control osteoporotic fractures.This review summarizes a number of advances made in the field of PTH and bone fracture to combat these injuries in humans and in animal models.The ultimate goal of providing an alternative to PTH,currently the sole anabolic therapy in clinical use,to promote bone formation and improve bone strength in the aging population is yet to be achieved.

Expression of hippocampal corticosteroid receptors,as well as corticotrophin-releasing hormone and vasopressin in the hypothalamic paraventricular nucleus,in fornix transected rats

BACKGROUND： The hippocampus regulates the hypothalamic-pituitary-adrenal axis through negative feedback. The hypothalamic paraventricular nucleus receives neuronal input from the hippocampus via the fomix, OBJECTIVE： To explore whether the negative feedback effect of the hippocampus on the hypothalamic-pituitary-adrenal axis is contributed to the inhibitory effect of mineralocorticoid receptor （MR） and glucocorticoid receptor （GR） in the hippocampus on the paraventricular nucleus via the fornix. DESIGN, TIME AND SETTING： Randomized, controlled, animal experiment. The study was performed at the Department of Histology and Embryology, China Medical University between September 2006 and September 2008. MATERIALS： Rabbit anti-rat anti-MR and rabbit anti-rat anti-GR antibodies were purchased from Santa Cruz Biotechnology, USA. Rabbit anti-rat anti-corticotrophin releasing hormone （CRH） and rabbit anti-rat anti-arginine vasopressin antibodies were purchased from Wuhan Boster. METHODS： A total of 90 male, Wistar rats were randomly divided into model and sham-surgery groups （n = 45）. Fornix transection was performed in the model group, while the sham-surgery group underwent surgery, but no fornix transection. MAIN OUTCOME MEASURES： Immunohistochemistry was used to examine MR and GR expression in the hippocampus, as well as CRH and anti-arginine vasopressin in the paraventricular nucleus. Western blot was used to measure alterations in MR, GR, and CRH protein expression following fomix transection. RESULTS： Compared with the sham-surgery group, there were no obvious changes in MR and GR expression in the hippocampus, or CRH and anti-arginine vasopressin expression in the paraventdcular nucleus within 4 days of fornix transection. However, after 7-10 days, significantly decreased MR and GR expression in the hippocampus, and increased CRH and anti-arginine vasopmssin expression in the paraventricular nucleus were observed （P 〈 0.05-0.01）. CONCLUSION： Negative feedback from the hippocampus on the hypothalamic-pituitary-adrenal axis might be mediated through the fornix, and the corticosterene actions mediated by hippocampal corticosteroid receptors indirectly modulated the hypothalamic-pituitary-adrenal axis.

Impact of parathyroid hormone on bone marrow-derived stem cell mobilization and migration

Parathyroid hormone(PTH) is well-known as the principal regulator of calcium homeostasis in the human body and controls bone metabolism via actions on the survival and activation of osteoblasts. The intermittent administration of PTH has been shown to stimulate bone production in mice and men and therefore PTH administration has been recently approved for the treatment of osteoporosis. Besides to its physiological role in bone remodelling PTH has been demonstrated to influence and expand the bone marrow stem cell niche where hematopoietic stem cells, capable of both self-renewal and differentiation, reside. Moreover, intermittent PTH treatment is capable to induce mobilization of progenitor cells from the bone marrow into the bloodstream. This novel function of PTH on modulating the activity of the stem cell niche in the bone marrow as well as on mobilization and regeneration of bone marrow-derived stem cells offers new therapeutic options in bone marrow and stem cell transplantation as well as in the field of ischemic disorders.

Development and validation of RP-HPLC and RP-UPLC methods for quantification of parathyroid hormones (1-34) in medicinal product formulated with meta-cresol

Rapid and sensitive reversed phase high performance liquid chromatography (RP-HPLC) and ultra performance liquid chromatography (RP-UPLC) method with UV detection has been developed and validated for quantification of parathyroid hormone (PTH) in presence of meta-cresol as a stabilizer in a pharmaceutical formulation.Chromatography was performed with mobile phase containing 0.1% Trifluoroacetic acid (TFA) in MilliQ water and 0.1% TFA in acetonitrile with gradient program and flow rate at 0.3 mL/min for HPLC and 0.4 mL/min for UPLC.Quantification was accomplished with internal reference standard (qualified against innovator product and National Institute for Biological Standards and Control (NIBSC) standard).The methods were validated for linearity (correlation coefficient 0.99),range,accuracy,precision and robustness.Robustness was confirmed by considering three factors;mobile phase composition,column temperature and flow rate/age of mobile phase.Intermediate precision was confirmed on different equipments,different columns and on different days.The relative standard deviation (RSD) (<2% for RP-HPLC and <1% for UPLC,n=30) indicated a good precision.Retention time was found about 17 min and 2 min by HPLC and UPLC methods,respectively.Both methods are simple,highly sensitive,precise and accurate and have the potential of being useful for routine quality control.

Effect of parathyroid hormone on apoptosis of human medullary thyroid carcinoma cells

Objective The aim of the study was to investigate the effect of parathyroid hormone(PTH) on the apoptosis of human medullary thyroid carcinoma(MTC) cells.Methods In vitro cultured medullary thyroid carcinoma cell lines were treated with parathyroid hormone and parathyroid hormone receptor-monoclonal antibody,and the apoptosis of cells was detected by flow cytometry.Results The cell morphology changed significantly after treatment based on the observation using the inverted phase-contrast microscope.Various concentrations of parathyroid hormone and parathyroid hormone receptor-monoclonal antibody effectively induced apoptosis in a time-and concentrationdependent manner.When the concentration of parathyroid hormone was 2.0 μmol/L and that of parathyroid hormone receptor-monoclonal antibody was 1.0 μmol/L,the apoptotic rate was 13.24% and 20.78%,respectively,representing a statistically significant difference from that of the control cells(P < 0.05).Conclusion PTH plays a role in inducing apoptosis of human MTC cells.

Inhibition effects of parathyroid hormone on human medullary thyroid carcinoma cells

Objective： The purpose of the study was to investigate the effects of parathyroid hormone and parathyroid hormone receptor monoclonal antibody on in vitro growth and proliferation of human medullary thyroid carcinoma cell lines. Methods： The medullary thyroid carcinoma cell line was cultured in vitro, with parathyroid hormone and parathyroid hormone receptor monoclonal antibody treatment intervention, the growth of the cells was observed under an inverted contrast micro scope, the MTT assay was used to detect the cell growth inhibition rate. Results： Under the inverted contrast microscope, the cells changed significantly, the parathyroid hormone and parathyroid hormone receptor monoclonal antibodies can effectively inhibit the proliferation of medullary thyroid cancer cells in a time and dose dependent. When parathyroid hormone concentra tion reached a concentration of 2.0 IJmol/L, the parathyroid hormone receptor monoclonal antibody reached a concentration of 1.0 μmol/L, the cell growth was most significantly inhibited （P 〈 0.05）. Conclusion： Parathyroid hormone and parathyroid hormone receptor monoclonal antibody were able to inhibit the proliferation of medullary thyroid carcinoma cells and signifi cantly reduce the proliferation index.

Variability of Serum Concentration of Calcium, Phosphate and Parathyroid Hormone Depending on Time of Blood Draw for Patients on Nocturnal Home Hemodialysis

Background: Guidelines for patients treated with conventional hemodialysis patients have been written for target serum levels for calcium (Ca), phosphate (PO4) and intact parathyroid hormone (iPTH). No guidelines exist for nocturnal home hemodialysis (NHHD) patients for target values or timing of the blood sample draw. We undertook a prospective cohort study to examine the variability in pre, post and clinic (post-post) serum values for Ca, PO4, and iPTH in NHHD patients to determine if timing of blood draw could affect clinical decisions. Methods: Twenty prevalent NHHD patients collected blood pre and post their usual NHHD session with an additional blood sample drawn in clinic (post-post). Median and interquartile range of pre, post and clinic (post-post) values of iPTH, PO4 and Ca were calculated and compared with Freidman/Wilcoxon test. Serum concentrations were also categorized according to Canadian Society of Nephrology (CSN) guidelines target values for pre and clinic (post-post) samples. The proportion of patients that would be categorized differently by clinic (post-post) samples was determined. Results: There was a significant difference between pre-serum values compared to post and clinic (post-post) values. Overall, iPTH, PO4 and Ca values would be misclassified in 25%, 70% and 50% respectively if blood was drawn at the clinic visit (post-post) compared to pre-HD as per CSN guidelines. Conclusions: Although no specific guideline has been written for NHHD patients, to ensure consistency of management compared to in-centre HD patients, lab values should be drawn pre-HD until clinical evidence suggests that the recommendations should be different for NHHD.

Study of serum level of sex hormones and expression of their receptors in patients with bronchogenic carcinoma

Objective: To study the serum level of estradiol, progesterone and testosterone (SEL, SPL and STL) and the expression of the receptors of estradiol and progesterone (ER and PR) in 53 cases of bronchogenic carcinoma. Methods: ER and PR in the tissue of the carcinoma were determined with enzyme-linked affinity histochemical method. SEL, SPL and STL were measured with double antibody radioimmunoassay. Results: Most of ER and PR were present in the cytoplasm of the malignant cells (58.2%) and the positive rates of ER and PR were 49.1% and 54.7% respectively. SEL and SPL were significantly higher in the patients with lung cancer than in the subjects of the control groups (P<0.05), no matter whether ER and PR were positive or negative. SEL and SPL were lower in the ER positive, PR positive and both ER and PR positive groups than in the ER negative, PR negative and both ER and PR negative groups. Conclusion: The existence of ER and PR in the patients with bronchogenic carcinoma indicates that the pathogenesis of bronchogenic carcinoma is sex hormone dependent to some extent. ER and SEL are negatively correlated with a correlative coefficient of -1.