Association between sensitivity to thyroid hormones and non-highdensity lipoprotein cholesterol levels in patients with type 2 diabetes mellitus

BACKGROUND Dyslipidemia and type 2 diabetes mellitus(T2DM)are chronic conditions with substantial public health implications.Effective management of lipid metabolism in patients with T2DM is critical.However,there has been insufficient attention given to the relationship between thyroid hormone sensitivity and dyslipidemia in the T2DM population,particularly concerning non-high-density lipoprotein cholesterol(non-HDL-C).AIM To clarify the association between thyroid hormone sensitivity and dyslipidemia in patients with T2DM.METHODS In this cross-sectional study,thyroid hormone sensitivity indices,the thyroid feedback quantile-based index(TFQI),the thyroid-stimulating hormone index(TSHI),the thyrotrophic T4 resistance index(TT4RI),and the free triiodothyronine(FT3)/free thyroxine(FT4)ratio were calculated.Logistic regression analysis was performed to determine the associations between those composite indices and non-HDL-C levels.Random forest variable importance and Shapley Additive Explanations(SHAP)summary plots were used to identify the strength and direction of the association between hyper-non-HDL-C and its major predictor.RESULTS Among the 994 participants,389(39.13%)had high non-HDL-C levels.Logistic regression analysis revealed that the risk of hyper-non-HDL-C was positively correlated with the TFQI(OR:1.584;95%CI:1.088-2.304;P=0.016),TSHI(OR:1.238;95%CI:1.034-1.482;P=0.02),and TT4RI(OR:1.075;95%CI:1.006-1.149;P=0.032)but was not significantly correlated with the FT3/FT4 ratio.The relationships between composite indices of the thyroid system and non-HDL-C levels differed according to sex.An increased risk of hyper-non-HDL-C was associated with elevated TSHI levels in men(OR:1.331;95%CI:1.003-1.766;P=0.048)but elevated TFQI levels in women(OR:2.337;95%CI:1.4-3.901;P=0.001).Among the analyzed variables,the average SHAP values were highest for TSHI,followed by TT4RI.CONCLUSION Impaired sensitivity to thyroid hormones was associated with high non-HDL-C levels in patients with T2DM.

Exploring the relationship between Hashimoto's thyroiditis and male fertility:A meta-analytic and meta-regression perspective on hormonal and seminal factors

Objective:To explore the relationship between Hashimoto's autoimmune hypothyroidism(HT)and male fertility,focusing on hormonal and seminal factors.Methods:A systematic literature search was conducted across databases such as PubMed,Web of Science,EMBASE,Scopus,Cochrane,and Google Scholar,covering studies published from January 2000 to March 2024.Studies investigating the impact of HT on semen quality parameters and reproductive hormones were included.Pooled effect estimates were calculated using standard mean difference(SMD)and 95%confidence intervals(CI).Results:A total of 8 studies with 8965 participants were included.HT significantly affected semen quality and reproductive hormone levels.Specifically,there was a notable decrease in progressive morphology(SMD=-0.78;95%CI:-1.40 to-0.17;P=0.01)and sperm motility(SMD=-1.151;95%CI:-1.876 to-0.425;P=0.002).In addition,there were no significant changes in reproductive hormones,although there were elevated levels of luteinizing hormone(SMD=0.437;95%CI:0.000 to 0.874;P=0.050)and follicle-stimulating hormone(SMD=0.293;95%CI:-0.171 to 0.758;P=0.216),with a slight impact on testosterone levels(SMD=-1.143;95%CI:-2.487 to 0.200;P=0.095).Conclusions:This systematic review and meta-analysis provides robust evidence of the detrimental effects of HT on semen quality and reproductive hormones,underscoring the necessity for thorough evaluation and management of thyroid function in male infertility assessments.

Effect of TSH Suppression Therapy on Sex Hormone Levels after Thyroid Cancer Surgery

Objective:To analyze the effect of thyroid-stimulating hormone(TSH)suppression therapy on sex hormone levels in patients undergoing postoperative treatment for thyroid cancer.Methods:A total of 40 patients undergoing postoperative thyroid cancer treatment were selected for data analysis.TSH suppression therapy was implemented during the postoperative period.Patients were grouped according to the TSH level:TSH<0.1,0.1≤TSH<0.5,and TSH≥0.5.Results:Among male patients,there were no significant differences in sex hormone levels at different dosing times and TSH levels(P>0.05).For female patients,testosterone levels at different dosing times showed no significant differences under the same circumstances(P>0.05).The comparison of testosterone levels at different TSH levels over 5 years of TSH suppression therapy did not yield significant differences(P>0.05).However,the comparison of testosterone levels within 5 years of TSH suppression therapy yielded significant differences(P<0.05),with the lowest levels observed at 0.1≤TSH<0.5.Conclusion:The use of TSH suppression therapy in postoperative thyroid cancer treatment minimally affects sex hormone levels in male patients.However,it has a significant impact on female patients.Therefore,preoperative sex hormone testing is recommended,and postoperative monitoring should include regular sex hormone testing.

Association of Serum Ferritin Levels and Thyroid Hormones

Thyroid metabolism is orchestrated by the action of various minerals and trace elements including iron, iodine, selenium, and zinc. Iron deficiency, specifically deficiency in serum ferritin levels, is one of the common causes of thyroid dysfunction. Our objective was to evaluate the relationship between serum ferritin levels and circulating thyroid hormones. For this, a retrospective analysis was performed on 16,512 individuals who tested for serum levels of ferritin and thyroid profile at Vibrant America Clinical Laboratories. Subjects were stratified based on the serum levels of ferritin. Age (p −0.03232, p < 0.0001). Analysis of Linear association by Pearson’s correlation exhibited a considerable correlation between varying serum ferritin levels with all tested thyroid hormones. The study concludes that serum ferritin levels were associated with thyroid hormone synthesis and metabolism in individuals with optimal levels of circulating ferritin.

Comparison of Thyroid Hormones Levels in Female Ducks Blood and Embryo

[Objeclive] The comparison of levels of thyroid hormones （T3, T4 and FT3） in female ducks serum and embryo of different embryonic age between Gaoyou duck and Jinding duck were made to provide basic data for further research. [Method] The levels of thyroid hormones （T3, T4 and FT3） in female ducks serum, fertilized eggs, and 7, 11,15, 19, 22, 28-days embryo of Gaoyou duck and Jinding duck were analyzed with radioimmunoassay （RIA）. [ Result]The levels of thyroid hormones in fertilized eggs were higher than those in serum of female ducks; different em- bryonic age hormone level of Gaoyou duck and Jinding duck in serum had almost the same variation trend, which was low but relatively stable after 15 days. [Condusion] The result suggested that thyroid hormones play an important role in duck embryonic development, especially in the early peded.

Analysis of the value and safety of thyroid-stimulating hormone in the clinical efficacy of patients with thyroid cancer

BACKGROUND Thyroid cancer(TC)is a common malignant tumor in the endocrine system.In recent years,the incidence and recurrence rates of TC have been raising due to increasing work pressure and irregular lifestyles.Thyroid-stimulating hormone(TSH)is a specific parameter for thyroid function screening.This study aims to explore the clinical value of TSH in regulating the progression of TC,so as to find a breakthrough for the early diagnosis and treatment of TC.AIM To explore the value and safety of TSH in the clinical efficacy of patients with TC.METHODS 75 patients with TC admitted to the Department of Thyroid and Breast Surgery of our hospital from September 2019 to September 2021 were selected as the observation group,and 50 healthy subjects were selected as the control group during the same period.The control group was treated with conventional thyroid replacement therapy,and the observation group was treated with TSH suppression therapy.The soluble interleukin(IL)-2 receptor(sIL-2R),IL-17,IL-35levels,free triiodothyronine(FT3),free tetraiodothyronine(FT4),CD3+,CD4+,CD8+,CD44V6,and tumor supplied group of factor(TSGF)levels were observed in the two groups.The occurrence of adverse reactions was compared between the two groups.RESULTS After treatment with different therapies,the levels of FT3,FT4,CD3+,and CD4+in the observation group and the control group were higher than those before treatment,while the levels of CD8+,CD44V6,and TSGF were lower than those before treatment,and the differences were statistically significant(P<0.05).More importantly,the levels of sIL-2R and IL-17 in the observation group were lower than those in the control group after 4 wk of treatment,while the levels of IL-35 were higher than those in the control group,and the differences were statistically significant(P<0.05).The levels of FT3,FT4,CD3+,and CD4+in the observation group were higher than those in the control group,and the levels of CD8+,CD44V6,and TSGF were lower than those in the control group.There was no significant difference in the overall incidence rate of adverse reactions between the two groups(P>0.05).CONCLUSION TSH suppression therapy can improve the immune function of patients with TC,lower the CD44V6 and TSGF levels,and improve serum FT3 and FT4 levels.It demonstrated excellent clinical efficacy and a good safety profile.

Correlation analysis of serum thyroglobulin,thyroid-stimulating hormone levels,and thyroid-cancer risk in thyroid nodule surgery

BACKGROUND Thyroglobulin(Tg)is one of the markers of thyroid cancer,and its concentration may be elevated in patients with malignant thyroid tumors.Thyroid-stimulating hormone(TSH)is secreted by the pituitary gland,which has a significant impact on thyroid gland function.Excessively high or low TSH levels may be associated with an increased risk of thyroid cancer.Thus,in-depth studies on the association of serum Tg and TSH levels with thyroid cancer risk in patients with thyroid nodules are warranted.This can help determine whether Tg and TSH levels can predict the degree of malignancy of thyroid nodules,which can in turn guide doctors in making accurate diagnoses and treatment decisions.Furthermore,such studies can provide more accurate diagnostic methods for thyroid nodules and help patients become aware of the presence of thyroid cancer as early as possible,thereby improving the success rate of treatment and prognosis.AIM To investigate the association of serum Tg and TSH levels with the risk of thyroid cancer in patients undergoing thyroid nodule surgery.METHODS The clinical data and laboratory examination results of 130 patients who underwent thyroid nodule surgery were retrospectively analyzed.Furthermore,their preoperative serum Tg and TSH levels were recorded.Histopathological examination conducted during follow-up revealed the presence of thyroid cancer.Correlation analysis were used to analyze the association of Tg and TSH levels with the risk of thyroid cancer.RESULTS Of the 130 patients,60 were diagnosed with thyroid cancer.Statistical analysis revealed a significant positive correlation between serum Tg levels and the risk of thyroid cancer(P<0.05).This suggests that high serum Tg levels are associated with an increased risk of thyroid cancer.However,no significant correlation was observed between serum TSH levels and the risk of thyroid cancer(P>0.05).CONCLUSION In patients who underwent thyroid nodule surgery,serum Tg levels exhibited a significant correlation with the risk of thyroid cancer but serum TSH levels did not.These findings suggest that serum Tg can serve as an important biomarker for assessing the risk of thyroid cancer in these patients.

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.

Stimulating effect of thyroid hormones in peripheral nerve regeneration:research history and future direction toward clinical therapy

Injury to peripheral nerves is often observed in the clinic and severe injuries may cause loss of motor and sensory functions.Despite extensive investigation,testing various surgical repair techniques and neurotrophic molecules,at present,a satisfactory method to ensuring successful recovery does not exist.For successful molecular therapy in nerve regeneration,it is essential to improve the intrinsic ability of neurons to survive and to increase the speed of axonal outgrowth.Also to induce Schwann cell phenotypical changes to prepare the local environment favorable for axonal regeneration and myelination.Therefore,any molecule that regulates gene expression of both neurons and Schwann cells could play a crucial role in peripheral nerve regeneration.Clinical and experimental studies have reported that thyroid hormones are essential for the normal development and function of the nervous system,so they could be candidates for nervous system regeneration.This review provides an overview of studies devoted to testing the effect of thyroid hormones on peripheral nerve regeneration.Also it emphasizes the importance of combining biodegradable tubes with local administration of triiodothyronine for future clinical therapy of human severe injured nerves.We highlight that the local and single administration of triiodothyronine within biodegradable nerve guide improves significantly the regeneration of severed peripheral nerves,and accelerates functional recovering.This technique provides a serious step towards future clinical application of triiodothyronine in human severe injured nerves.The possible regulatory mechanism by which triiodothyronine stimulates peripheral nerve regeneration is a rapid action on both axotomized neurons and Schwann cells.

Thyroid hormones in male reproduction and infertility

Thyroid hormones have been well studied for its relevance to male reproduction in the last few decades. They are considered as essential regulators of male reproductive functions and play vital roles in male gonadal developments. Hyperthyroidism and hypothyroidism both affect testicular functions and influence neuroendocrine regulations over reproductive functionsvia the crosstalk between the hypothalamic-pituitary-thyroid axis and the hypothalamic-pituitary-gonadal axis. The alterations in the male reproductive hormonal milieu by thyroid hormones may lead to reduced testosterone levels and deterioration of semen quality. However, there are very few reports on the direct effects of thyroid disorders upon testicular functions and semen quality. This article aims to review the available literature to present a concise updated concept on the regulation of male reproductive functions by the thyroid hormones, and the possible mechanism by which thyroid dysfunctions affects testicular functions.

Toxic Effects of Tetrabromobisphenol A on Thyroid Hormones in SD Rats and the Derived-reference Dose

The present study determined the thyroid hormone interference of tetrabromobisphenol A （TBBPA） in Sprague-Dawley （SD） rats, and the derived-reference dose （RfD） of different endpoint effects on mammals based on experimental results and data collection. Based on repeated exposure toxicity tests on mammals and extensive research, the present study used BMDS240 Software to derive a benchmark dose, and analyzed the accuracy and uncertainty, and similarity with other studies. Test results on triiodothyronine （T3）, thyroxine （T4）, and thyroid stimulating hormone （TSH） demonstrated that all the indicators presented a non-monotonous dose-effect relationship clearly, except TSH in male rats exposed to 0-1000 mg/kg BW per day. Therefore, RfDs were derived from different critical effects. In summary, RfD for mammals in the present study was found to be 0.6 mg/kg per day.

Iodothyronine deiodinase gene analysis of the Pacific oyster Crassostrea gigas reveals possible conservation of thyroid hormone feedback regulation mechanism in mollusks

Iodothyronine deiodinase catalyzes the initiation and termination of thyroid hormones(THs) effects, and plays a central role in the regulation of thyroid hormone level in vertebrates. In non-chordate invertebrates, only one deiodinase has been identified in the scallop C hlamys farreri. Here, two deiodinases were cloned in the Pacific oyster C rassostrea gigas( Cg Dx and C g Dy). The characteristic in-frame TGA codons and selenocysteine insertion sequence elements in the oyster deiodinase c DNAs supported the activity of them. Furthermore, seven orthologs of deiodinases were found by a tblastn search in the mollusk Lottia gigantea and the annelid C apitella teleta. A phylogenetic analysis revealed that the deiodinase gene originated from an common ancestor and a clade-specific gene duplication occurred independently during the differentiation of the mollusk, annelid, and vertebrate lineages. The distinct spatiotemporal expression patterns implied functional divergence of the two deiodinases. The expression of C g Dx and Cg Dy was influenced by L-thyroxine T4, and putative thyroid hormone responsive elements were found in their promoters, which suggested that the oyster deiodinases were feedback regulated by TH. Epinephrine stimulated the expression level of C g Dx and Cg Dy, suggesting an interaction effect between different hormones. This study provides the first evidence for the existence of a conserved TH feedback regulation mechanism in mollusks, providing insights into TH evolution.

Association between lifestyle factors and thyroid function in young euthyroid adults

Purpose:The present work examines the associations of dietary habits,sedentarism,physical activity(PA)levels and sleep habits,with thyroid function in young euthyroid adults.Methods:A total of 105 young euthyroid adults participated in this cross-sectional study.Thyroid function was determined in fasting conditions(>6 h).Dietary habits were measured by a food frequency questionnaire and three non-consecutive 24 h recalls,and different dietary intake and patterns were then estimated.The time spent in sedentary,PA levels and sleep habits were objectively measured using a wrist-worn accelerometer.Results:Energy and carbohydrate intake were positively associated with thyroid stimulating hormone(TSH)(β=0.222;R^(2)=0.102;P=0.022 andβ=0.425;R^(2)=0.129;P=0.007,respectively)whereas fat intake was negatively associated with TSH(β=-0.428;R^(2)=0.137;P=0.004).Energy intake was also positively associated with free triiodothyronine(β=0.277;R^(2)=0.137;P=0.004).Further,adherence to the Mediterranean diet was negatively related to TSH and free thyroxine(FT4)(β=-0.221;R^(2)=0.113;P=0.020 andβ=-0.268;R^(2)=0.071;P=0.007,respectively).Vigorous-intensity and overall PA were negatively associated with FT4(β=-0.227;R^(2)=0.052;P=0.022 andβ=-0.204;R^(2)=0.042;P=0.041,respectively).In contrast,no associations were found between sleep parameters and thyroid function.Conclusions:Lifestyle factors such as dietary intake and PA levels seems to be related to thyroid function even in young euthyroid adults.

Reference Interval of Thyroidal Function of Women in the Early,Middle and Late Pregnancy in Jingzhou City,Hubei Province

[Objectives]To study the reference value of thyroid function in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City.[Methods]362 healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)were selected as the study group,and 360 non-pregnant women were selected as the control group.Serum thyroid hormone levels in the two groups were detected,and the reference value was expressed as the median(M)and 95%confidence interval(CI).On this basis,the chart of changing trend of thyroid hormone in the early,middle and late pregnancy were plotted.[Results]Compared with the control group,FT3,TT4,TT3,FT4and TSH in the early,middle and late pregnancy were significantly different in the study group(P<0.05).In the study group,there were significant differences in the early,middle and late pregnancy(P<0.05).[Conclusions]This trend chart has certain reference value in the screening,diagnosis and treatment of thyroid diseases in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City of Hubei Province.

Selective Pituitary Resistance to Thyroid Hormone: Clinical Hyperthyroidism with High TSH on Levothyroxine Administration in I-131 Ablated “Graves Disease”

Resistance to Thyroid Hormone (RTH) is a rare form of hormone resistance secondary to changes in the genes encoding thyroid hormone receptors. The two subtypes, Pituitary RTH (PRTH) and Generalized RTH (GRTH), cause clinically distinguishable patient presentations. In PRTH, typically only the pituitary gland is resistant to thyroid hormone (TH) while the rest of the body maintains sensitivity. Selective pituitary resistance to thyroid hormone results in dysregulation of thyroid hormone homeostasis with clinical presentation as either euthyroid or hyperthyroidism. PRTH is characterized by elevated thyroid hormone levels with an elevated or inappropriately normal TSH concentration. Herein we describe a case report of a 70-year-old woman who complained of weight loss of over 35 lbs., palpitations, jitters, hair loss, diarrhea, fatigue, muscle weakness, etc. over 6 months, thus, indicating the presence of iatrogenic hyperthyroidism while receiving levothyroxine 175 ug daily prescribed by her primary care provider because of a reported history of “Graves disease” treated by radioactive iodine ablation of the thyroid several years ago. The daily dose of levothyroxine had been increased gradually at an interval of 3 months over a year because of persistent elevation of serum TSH level. Laboratory tests revealed markedly elevated Free T4, Free T3 and TSH levels, along with low concentrations of all lipid fractions, serum creatinine and urea nitrogen levels, indicating TSH induced hyperthyroidism or PRTH. Further testing documented a mutation of thyroid hormone receptor beta gene 2 confirming presence of PRTH. We believe that the initial diagnosis of Graves Disease was erroneous and I-131 ablation further confounded and missed the diagnosis of PRTH. Thus, the purpose of this report is to report a patient with PRTH and describe potential pitfalls in diagnosis and management of this rare disorder.

Characteristics of Thyroid Hormones in Hypertensive Hispanic Population

The aim was to characterize thyroid function in Hispanic hypertensive population. Retrospective study of 1,023 individuals was performed, in which 68.23% had hypertension （74.21% women） and 37.25% had thyroid pathology. Age, weight, blood pressure, biochemical measurements were recorded, mean age： 53.02 ± 14.80 yr, mean weight： 83.05 ±16.95 kg, thyrotropin-stimulating hormone （TSH） hypertensive patients： 5.55±1.63 μUI/mL and without hypertension： 3,72 ± 1.60 μUI/mL. TSH range concentration distributed by sex indicates： 1.50-2.49 μUI/mL men, 2.50-5.01 μUI/mL women. TSH categories vs. age were positively associated （r = ＋ 0.114, P = 0.044） and hypertension by age was also correlated （r = ＋ 0.178, P = 0.0001）. Significant positive association we found between TSH and diastolic blood pressure （r = ＋ 0.197, P = 0.008）. Systolic and diastolic blood pressure vs. age were positively increasing （r = ＋ 0.410,p = 0.0001; r = ＋0.285, P = 0.0001, respectively）. Prevalence of thyroid pathology in hypertensive subjects are hyperthyroidism 5.87%; hypothyroidism 20.34% （5.73% subclinic） and autoimmune disease 6.25%. High percentage of hypertensive population has concomitant thyroid diseases, more common in women （50-70 years）. Systematic surveillance for occult thyroid dysfunction in patients with hypertension could prevent future cardiovascular disease.

Feeding Supplemental lodine to Adult Mink;Effect on Thyroid Hormones in Adult and offspring

We fed adult mink diets containing supplemental iodine, from 0 to 320 ppm, for one or seven months prior to breeding. Blood samples collected from the adults and their offspring (kits) at 4 wk post-partum were assayed for total thyroxine (T4), triiodothyronine (T3), reverse T3 (rT3), and T4-binding indices. As expected T4 concentrations of the adult and kit mink varied inversely with the level of supplemental iodine. In addition, T3 and rT3 concentrations decreased gradually in kits from the long-term experiment in response to the increased dietary iodine of the dams. T3 concentrations of kits from dams fed iodine short-term decreased markedly while rTy concentrations were elevated greatly in response to increased dietary iodine of the dam. These decreases in hormone levels are due to serum iodine blocking the thyroid uptake of iodine and subsequent decrease of hormone synthesis. Excess iodine may also block the effect of thyroid stimulating hormone. The T4-binding indices of the adults, in general, were depressed, while the T4-binding indices of the kits were more variable. These effects are probably due to fluctuations in thyroglobulin.

Serum Level of Thyroid Hormones in Patients with Chronic Hepatitis C Virus Infection

Objective: There are clinical and laboratory associations between thyroid and liver diseases. Hepatitis C virus (HCV) is known to be responsible for both hepatic and extrahepatic diseases. The most frequent and clinically important endocrine extrahepatic diseases are thyroid disorders and type 2 diabetes mellitus. We aim to study the relationship between the serum level of thyroid hormones (THs) and the severity of liver disease in patients with chronic hepatitis C virus (CHC) infection. Methods: 60 patients with CHC infection were selected for the study. They were divided into two groups: with or without liver cirrhosis. Those with liver cirrhosis were further subdivided according to the Child-Turcotte-Pugh scoring system. Serum levels of free T3 (FT3), free T4 (FT4) and TSH were measured to all patients. Results: There was decrease in the FT3 and FT4 levels and increase in the TSH levels in patients with CHC with cirrhosis when compared to patients with CHC without cirrhosis. Conclusion: Thyroid profile abnormalities were seen in cirrhotic HCV patients when compared to non-cirrhotic patients. The abnormalities in the serum level of THs (decreased FT3, FT4, and increased TSH) are strongly associated with the severity of liver damage and advancing of the child score.

The Relation between Thyroid Hormone and Blood Lipid in the Healthy Elderly

Objectives To observe the relationship between Thyroid Hormone (TH) level and blood lipid level in the healthy elderly with therapy of small dose of TH. Methods A total of 120 healthy old persons were randomly divided into two groups: 60 old persons as treatment group and other 60 persons as control group. Each person in the treatment group took a thyroid tablet 10 mg daily continuously for six months while the control group took VitB1 30 mg daily instead of thyroid tablet. The level of TH, M -TSH, FT3, FT4, TT4, rT3, TC, TG, LDL - C, HDL-C, ApoA1 were measured in two groups before and after receiving TH or Vit. B1 treatment. Results In the treatment group the level of TH increased obviously. And TC, TG, LDL - C levels decreased also to some extent while HDL - C, ApoAl levels increased slightly which was significant when compared with the control group and pre - treatment group. Conclusions To use small dose of TH as supplement treatment can increase the TH level of healthy old persons and decrease their blood lipid level. It would be a benefit for treating hyperlipidemia in the elderly.

Assessment of LLLT systemic effects on thyroid hormones function after dental titanium implant installation:An experimental rabbit model

This study aimed to assess the systemic effect of LLLT on thyroid gland functioning and consequently on calcium regulation through Triiodothyronine (T3) and Thyroxine (T4) measurements in rabbits’ serum. A total of thirty two New Zealand male rabbits were randomly distributed in four groups with eight animals each: control group C (nonirradiated animals), group EI (5 J/cm2 per session), group EII (10 J/cm2 per session) and group EIII (20 J/cm2 per session). All animals underwent lower left incisor extraction followed by immediate insertion of an osseintegrated implant, providing an equality of initial clinical condition between the groups. The experimental groups were irradiated with aluminium gallium arsenide diode laser (GaAlAs, λ = 830 nm, 50 mW, CW), during 13 days at each 48 hours, totalizing 7 sessions. Laboratorial T3 and T4 measurements were done in four distinct moments (before surgical procedure, immediately after surgical procedure, after the first LLLT session and after the last LLLT session) in all animals. The results obtained showed statistically significant differences in Triiodothyronine values between the groups throughout the experiment. It was concluded that the LLLT, in the protocol of irradiation used in this study, promoted a significantly alteration on rabbits’ serum hormonal levels.