Displaying publications 41 - 52 of 52 in total

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  1. Ogawa S, Ng KW, Xue X, Ramadasan PN, Sivalingam M, Li S, et al.
    PMID: 24324459 DOI: 10.3389/fendo.2013.00184
    Kisspeptin has recently been recognized as a critical regulator of reproductive function in vertebrates. During the sexual development, kisspeptin neurons receive sex steroids feedback to trigger gonadotropin-releasing hormone (GnRH) neurons. In teleosts, a positive correlation has been found between the thyroid status and the reproductive status. However, the role of thyroid hormone in the regulation of kisspeptin system remains unknown. We cloned and characterized a gene encoding kisspeptin (kiss2) in a cichlid fish, the Nile tilapia (Oreochromis niloticus). Expression of kiss2 mRNA in the brain was analyzed by in situ hybridization. The effect of thyroid hormone (triiodothyronine, T3) and hypothyroidism with methimazole (MMI) on kiss2 and the three GnRH types (gnrh1, gnrh2, and gnrh3) mRNA expression was analyzed by real-time PCR. Expression of thyroid hormone receptor mRNAs were analyzed in laser-captured kisspeptin and GnRH neurons by RT-PCR. The kiss2 mRNA expressing cells were seen in the nucleus of the lateral recess in the hypothalamus. Intraperitoneal administration of T3 (5 μg/g body weight) to sexually mature male tilapia significantly increased kiss2 and gnrh1 mRNA levels at 24 h post injection (P thyrotropin-releasing hormone mRNA levels were insensitive to the thyroid hormone manipulations. Furthermore, RT-PCR showed expression of thyroid hormone receptor mRNAs in laser-captured GnRH neurons but not in kiss2 neurons. This study shows that GnRH1 may be directly regulated through thyroid hormone, while the regulation of Kiss2 by T3 is more likely to be indirect.
    Matched MeSH terms: Thyrotropin-Releasing Hormone
  2. Mohd Said MS, Bin Shudim SS, Mohamad K, Shaharir SS, Kong NCT, Ali RA
    Egyptian Rheumatologist, 2016;38:189-194.
    DOI: 10.1016/j.ejr.2015.12.001
    Aim of the work This work aimed to determine the frequency of subclinical memory dysfunction in a group of Malaysian systemic lupus erythematosus (SLE) patients and to study its relation to clinical characteristics, laboratory investigations and disease activity. Patients and methods Fifteen SLE patients attending the Universiti Kebangsaan Malaysia Medical Centre (UKMMC) and not known to have neuropsychiatric lupus were recruited. These patients were assessed using the Wechsler Memory Scale. Disease activity was assessed using the SLE disease activity index 2000 (SLEDAI-2K). Results The median age of the patients was 28 years (25–37 years) and they were 14 females and one male. Their median disease duration was 9.3 years (4.8–10 years). Their median SLEDAI-2K was 4 (0–6). Memory dysfunction was identified in 7/15 (46.7%) SLE patients and was significantly associated with lower serum thyroxine levels (median 12.27; 11.8–13.3 μg/dl) (p = 0.027) compared to those without memory impairment (15.48; 14.39–16.56 μg/dl). Auditory memory impairment was associated with the education level as the auditory memory index was significantly lower in patients with secondary education (n = 7, median 88; 86.5–91.5) compared to those who received tertiary education (n = 8, median 103; 97.5–119.5) (p = 0.025) while visual memory was influenced by disease duration (p = 0.016). There was no association between overall memory dysfunction and disease duration, number of relapses, clinical manifestations and SLEDAI-2K scores. Conclusion There is a high frequency of subclinical memory dysfunction among SLE patients. A remarkable association is present with lower thyroxine. Auditory memory impairment is related to the level of education and visual memory to disease duration. © 2015 The Authors
    Matched MeSH terms: Thyrotropin
  3. Mongolu S, Armston AE, Mozley E, Nasruddin A
    Scand J Clin Lab Invest, 2016 May;76(3):240-2.
    PMID: 26924790 DOI: 10.3109/00365513.2016.1143113
    Assay interference with heterophilic antibodies has been well described in literature. Rheumatoid factor is known to cause similar interference leading to falsely elevated hormone levels when measured by immunometric methods like enzyme-linked immunosorbent assay (ELISA) or multiplex immunoasays (MIA). We report a case of a 60-year-old male patient with a history of rheumatoid arthritis referred to our endocrine clinic for investigation of hypogonadism and was found to have high serum levels of LH, FSH, SHBG, Prolactin, HCG and TSH. We suspected assay interference and further tests were performed. We used Heteroblock tubes and PEG precipitation to eliminate the interference and the hormone levels post treatment were in the normal range. We believe the interference was caused by high serum levels of rheumatoid factor. Although he was treated with thyroxine for 3 years, we believe he may have been treated inappropriately as his Free T4 level was always normal despite high TSH due to assay interference. Our case illustrates the phenomenon of heterophilic antibody interference likely due to high levels of rheumatoid factor. It is essential for clinicians and endocrinologists in particular to be aware of this possibility when making treatment decisions in these groups of patients.
    Matched MeSH terms: Thyrotropin
  4. Sayem ASM, Giribabu N, Karim K, Si LK, Muniandy S, Salleh N
    Biomed Pharmacother, 2018 Apr;100:132-141.
    PMID: 29428660 DOI: 10.1016/j.biopha.2018.02.008
    Sex-steroids play important role in modulating uterine functions. We hypothesized that these hormones affect expression of proteins in the uterus related to thyroid hormone action. Therefore, changes in expression levels of receptors for thyroid hormone (TRα-1 and TRβ-1), thyroid stimulating hormone (TSHR), vitamin D (VDR) and retinoid acid (RAR) as well as extracellular signal-regulated kinase (ERK1/2) in uterus were investigated under sex-steroid influence.

    METHODS: Two rat models were used: (i) ovariectomised, sex-steroid replaced and (ii) intact, at different phases of oestrous cycle. A day after completion of sex-steroid treatment or following identification of oestrous cycle phases, rats were sacrificed and expression and distribution of these proteins in uterus were identified by Western blotting and immunohistochemistry, respectively.

    RESULTS: Expression of TRα-1, TRβ-1, TSHR, VDR, RAR and ERK1/2 in uterus was higher following estradiol (E2) treatment and at estrus phase of oestrous cycle when E2levels were high. A relatively lower expression was observed following progesterone (P) treatment and at diestrus phases of oestrous cycle when P levels were high. Under E2influence, TRα, TRβ, TSHR, VDR, RAR and ERK1/2 were distributed in luminal and glandular epithelia while under P influence, TSHR, VDR abn RAR were distributed in the stroma.

    CONCLUSIONS: Differential expression and distribution of TRα-1, TRβ-1, TSHR, VDR, RAR and ERK1/2 in different uterine compartments could explain differential action of thyroid hormone, TSH, vitamin D, and retinoic acid in uterus under different sex-steroid conditions.

    Matched MeSH terms: Thyrotropin
  5. Anuar Zaini A, Feng Tung Y, Ahmad Bahuri NF, Yazid Jalaludin M
    J ASEAN Fed Endocr Soc, 2020;35(1):62-67.
    PMID: 33790495 DOI: 10.15605/jafes.035.01.11
    Introduction: The causes of congenital hypothyroidism (CHT) are thyroid dysgenesis (TD), dyshormonogenesis (TDH) or transient hypothyroidism (TH).

    Methodology: This is a cross-sectional study looking at data over a period of 16 years (2000-2016). Confirmed cases had thyroid scan at the age of 3-years-old and repeated TFT (after 6 weeks off medications). Relevant data was collected retrospectively.

    Results: Forty (60% female) children with CHT were included in the study. Thirty (75%) children presented with high cord TSH. Nine (23%) presented after 2 weeks of life. Majority were diagnosed with TDH (42.5%) with TD and TH of 40% and 17.5% respectively. Median cord TSH of children with TD was significantly higher compared to TDH and TH (p=0.028 and p=0.001 respectively). L-thyroxine doses were not significantly different between TD, TDH and TH at diagnosis or at 3 years.

    Conclusions: TDH is highly prevalent in our population. TD may present after 2 weeks of life. One in five children treated for CHT had TH. Differentiating TD, TDH and TH before initiating treatment remains a challenge in Malaysia. This study provides clinicians practical information needed to understand the possible aetiologies from a patient's clinical presentation, biochemical markers and treatment regime. Reassessing TH cases may be warranted to prevent unnecessary treatment.

    Matched MeSH terms: Thyrotropin
  6. Zaleha MI, Osman A, Iskandar ZA, Sazali S, Ali MM, Roslan I, et al.
    Asia Pac J Clin Nutr, 1998 Jun;7(2):138-50.
    PMID: 24393641
    In order to study the effect of levothyroxine in the treatment of endemic goitre, a longitudinal study was conducted among the Aborigines in Lanai Post and Sinderut Post, situated in an iodine-deficient area located in the district of Kuala Lipis, Pahang. All subjects in the treatment group (Lanai Post) were given 100 µg of levothyroxine per day and were followed for 1 1/2 years. A total of 311 subjects were examined at baseline, 323 on the first, 256 on the second, 239 on the third and 184 on the fourth visit following levothyroxine supplementation. Goitre prevalence, thyroid hormones, thyroid volume, nutritional status, urinary iodine levels, arterial blood pressure and mental performance were determined. Following the intervention, goitre prevalence was significantly reduced in the treatment group (baseline 42.8% vs final visit 13.0%, p<0.0001); however, no significant difference was noted in the control group. Total T4 levels were increased in the treatment group (p<0.0001), while a significant reduction was noted in the control group (p<0.0001). Thyroid-stimulating hormone levels increased significantly in the treatment group following 1 year of intervention, while no significant changes were observed in the control group. As for the thyroid volume, both groups showed a significant increment following the intervention (p<0.0001). With respect to the nutritional status, the treatment group showed a significant increase in body weight following the intervention (p<0.05). In addition, the mid-arm circumference and body mass index also increased after 1 year of intervention. However, the control group showed a reduction in the waist-hip ratio (p<0.0001). Although there was no statistical difference in the waist-hip ratio in the treatment group, there has been a significant reduction observed after 1 year of intervention. At 1 year, a reduction in skinfold thickness was noted in the treatment group while only the triceps and subscapular were increased in the control group. The body fat was decreased in the treatment group following 1 year of intervention (p<0.0001). No particular trend was noted in the urinary iodine excretion in the treatment group, but surprisingly, the levels were increased in the control group (p<0.0001). A significant increase in both systolic and diastolic blood pressures was observed in the treatment group following 1 year of intervention, but the controls showed a reduction in the systolic blood pressure (p<0.0001). Both groups showed a remarkable increase in mental performance, with a more pronounced effect in the treatment group (p<0.05). The correction of iodine deficiency by levothyroxine supplementation has a short-term beneficial effect in reducing the prevalence of goitre and improving the mental ability among the Aborigines in endemic areas; however, proper monitoring and close supervision are needed to maintain compliance.
    Matched MeSH terms: Thyrotropin
  7. Isa ZM, Alias IZ, Kadir KA, Ali O
    Asia Pac J Clin Nutr, 2000 Dec;9(4):274-81.
    PMID: 24394503
    Although endemic goitre is no longer a major public health problem in Malaysia, iodine deficiency still remains a significant problem in a few remote settlements. The aim of this study was to determine the effectiveness of iodized oil intervention in the prevention of endemic goitre among the indigenous people in Malaysia. A pretest and post-test controlled trial was conducted among primary schoolchildren and pregnant mothers in Lasah, Sungai Siput and Perak. Legap Post and Yum Post were selected as the intervention areas, while Perwor Post and Poi Post were taken as controls. The variables studied included thyroid hormone concentrations, thyroid volume, urinary iodine excretions and mental performance. A baseline and two follow-up visits were conducted in both intervention and control areas. Intervention subjects were given iodized oil in the form of capsules which were taken orally (Laboratoire Guerbet, Paris, France). There was a significant increase in serum thyroxine hormone (T4) concentrations (p<0.0001) and a significant decrease in thyroid stimulating hormone (TSH) concentrations (p<0.05) in the schoolchildren following the intervention, however, pregnant mothers did not show any significant changes in T4 and TSH concentrations. Thyroid size was significantly reduced in both groups (p<0.05). Urinary iodine excretions showed a significant increase in both groups following the intervention (p<0.01). However, mental performance in schoolchildren was not affected. In conclusion, iodized oil (oral) is effective in reducing thyroid size, as well as improving the supply of iodine among schoolchildren and pregnant mothers in endemic goitre areas; however, its long-term effects need to be monitored closely. This method can be considered as an alternative while awaiting national coverage for the salt iodization program.
    Matched MeSH terms: Thyrotropin
  8. Ratnasingam J, Karim N, Paramasivam SS, Ibrahim L, Lim LL, Tan AT, et al.
    Pituitary, 2015 Aug;18(4):448-55.
    PMID: 25134488 DOI: 10.1007/s11102-014-0593-6
    PURPOSE: Radiation fields for nasopharyngeal cancer (NPC) include the base of skull, which places the hypothalamus and pituitary at risk of damage. We aimed to establish the prevalence, pattern and severity of hypothalamic pituitary (HP) dysfunction amongst NPC survivors.

    METHODS: We studied 50 patients (31 males) with mean age 57 ± 12.2 years who had treatment for NPC between 3 and 21 years (median 8 years) without pre-existing HP disorder from other causes. All patients had a baseline cortisol, fT4, TSH, LH, FSH, oestradiol/testosterone, prolactin and renal function. All patients underwent dynamic testing with insulin tolerance test to assess the somatotroph and corticotroph axes. Baseline blood measurements were used to assess thyrotroph, gonadotroph and lactotroph function.

    RESULTS: Hypopituitarism was present in 82% of patients, 30% single axis, 28% two axes, 18% three axes and 6% four axes deficiencies. Somatotroph deficiency was most common (78%) while corticotroph, gonadotroph and thyrotroph deficiencies were noted in 40% (4 complete/16 partial), 22 and 4% of the patients respectively. Hyperprolactinaemia was present in 30% of patients. The development of HP dysfunction was significantly associated with the time elapsed from irradiation, OR 2.5 (1.2, 5.3), p = 0.02, for every 2 years post treatment. The use of concurrent chemo-irradiation (CCRT) compared to those who had radiotherapy alone was also significantly associated with HP dysfunction, OR 14.5 (2.4, 87.7), p < 0.01.

    CONCLUSION: Despite low awareness and detection rates, HP dysfunction post-NPC irradiation is common. Use of CCRT may augment time related pituitary damage. As these endocrinopathies result in significant morbidity and mortality we recommend periodic assessment of pituitary function amongst NPC survivors.

    Matched MeSH terms: Thyrotropin/blood
  9. Sakinah SO, Khalid BA, Aishah AB
    Ann Acad Med Singap, 1993 Jul;22(4):563-6.
    PMID: 8257059
    A study to determine the prevalence of goitre and abnormal thyroid status during pregnancy in Malaysian women was conducted. Two hundred and three women (Malay = 85, Chinese = 47 and Indian = 71) in the third trimester and with no known thyroid disease were studied. There was a marked racial disparity in the prevalence of goitre: Indian 61%, Malay 28% and Chinese 29% (p = 0.001). The serum thyrotropic hormone (TSH) was significantly higher in Indians (median: 1.36 uIU/ml) compared to Malays (1.14 uIU/ml, p = 0.009). The serum albumin was also significantly lower in Indians (mean +/- sd; 36.12 +/- 3.9 mmol/l) compared to Malays (39.3 +/- 4.8 mmol/l) or Chinese (39.1 +/- 5.2) (p < 0.001). Thyroid antibody was detected in 14.6% of these women with no significant racial difference in its prevalence. Three women were found to be thyrotoxic but none were hypothyroid. This study found a high prevalence of goitre among the pregnant Indian women, probably related to the protein malnutrition state. The high prevalence of positive thyroid antibody in our population indicates that a high percentage of women are at risk of developing postpartum thyroiditis.
    Matched MeSH terms: Thyrotropin/blood
  10. Kitahashi T, Ogawa S, Soga T, Sakuma Y, Parhar I
    Endocrinology, 2007 Dec;148(12):5822-30.
    PMID: 17823257
    The role of steroid/thyroid hormones in the regulation of endocrine cells at the level of the pituitary has remained unclear. Therefore, using single-cell quantitative real-time PCR, we examined absolute amounts of transcripts for nuclear receptors [estrogen receptors (ERs) alpha, beta, and gamma; androgen receptors (ARs) a and b; glucocorticoid receptors (GRs) 1, 2a, and 2b; and thyroid hormone receptors (TRs) alpha1, alpha2, and beta] in pituitary cells of immature (IM) and mature (M) male tilapia, Oreochromis niloticus. In the two reproductive stages, ACTH cells expressed only ERbeta, whereas all other pituitary cell types expressed ERalpha + beta, and a subpopulation coexpressed ARa, ARb, GR1, GR2b, and TRbeta but lacked ERgamma, GR2a, TRalpha1, and TRalpha2. IM males had high percentages of LH cells (IM 46.0% vs. M 10.0%), GH cells (IM 23.3% vs. M 7.9%), and prolactin cells (IM 68.8% vs. M 6.0%) with ERbeta, and TSH cells (IM 19.2% vs. M 0.0%) and MSH cells (IM 25.6% vs. M 0.0%) with ERalpha + TRbeta. A high percentage of FSH cells in IM males expressed ERbeta (IM 46.9% vs. M 18.8%), and FSH cells in M males showed significantly high GR1 transcripts (IM 76.0 +/- 5.0 vs. M 195.0 +/- 10.7 copies per cell; P < 0.05), suggesting that FSH cells are regulated differently in the two reproductive stages. Coexpression of ERalpha + beta in high percentages of cells of the GH family (GH, IM 43.8% vs. M 14.3%; prolactin, IM 8.3% vs. M 59.7%; somatolactin, IM 22.2% vs. M 42.2%) suggests that the expression of both ERs is important for functionality. Thus, differential coexpression of genes for nuclear receptors in subpopulations of pituitary cell types suggests multiple steroid/thyroid hormone regulatory pathways at the level of the pituitary during the two reproductive stages.
    Matched MeSH terms: Thyrotropin/genetics; Thyrotropin/metabolism
  11. Hang CY, Kitahashi T, Parhar IS
    J. Comp. Neurol., 2014 Dec 1;522(17):3847-60.
    PMID: 25043553 DOI: 10.1002/cne.23645
    In addition to vision, light information is used to regulate a range of animal physiology. Such nonimage-forming functions of light are mediated by nonvisual photoreceptors expressed in distinct neurons in the retina and the brain in most vertebrates. A nonvisual photoreceptor vertebrate ancient long opsin (VAL-opsin) possesses two functional isoforms in the zebrafish, encoded by valopa and valopb, which has received little attention. To delineate the neurochemical identities of valop cells and to test for colocalization of the valop isoforms, we used in situ hybridization to characterize the expression of the valop genes along with that of neurotransmitters and a neuropeptide known to be present at the sites of valop expression. Double labeling showed that the thalamic valop population coexpresses valopa and valopb. All the thalamic valop cells overlapped with a GABAergic cell mass that continues from the anterior nucleus to the intercalated thalamic nucleus. A novel valopa cell population found in the superior raphe was serotonergic in nature. A valopb cell population in the Edinger-Westphal nucleus was identified as containing thyrotropin-releasing hormone. Valopb cells localized in the hindbrain intermediate reticular formation were noncholinergic in nature (nonmotorneurons). Thus, the presence of valop cell populations in different brain regions with coexpression of neurotransmitters and neuropeptides and the colocalization of valop isoforms in the thalamic cell population indicate regulatory and functional complexity of VAL-opsin in the brain of the zebrafish.
    Matched MeSH terms: Thyrotropin-Releasing Hormone
  12. Tan JYL, Loh KC, Yeo GSH, Chee YC
    BJOG, 2002 Jun;109(6):683-8.
    PMID: 12118648
    OBJECTIVE: To characterise the clinical, biochemical and thyroid antibody profile in women with transient hyperthyroidism of hyperemesis gravidarum.
    DESIGN: Prospective observational study.
    SETTING: Hospital inpatient gynaecological ward.
    POPULATION: Women admitted with hyperemesis gravidarum and found to have hyperthyroidism.
    METHODS: Fifty-three women were admitted with hyperemesis gravidarum and were found to have hyperthyroidism. Each woman was examined for clinical signs of thyroid disease and underwent investigations including urea, creatinine, electrolytes, liver function test, thyroid antibody profile and serial thyroid function test until normalisation.
    MAIN OUTCOME MEASURES: Gestation at which thyroid function normalised, clinical and thyroid antibody profile and pregnancy outcome (birthweight, gestation at delivery and Apgar score at 5 minutes).
    RESULTS: Full data were available for 44 women. Free T4 levels normalised by 15 weeks of gestation in the 39 women with transient hyperthyroidism while TSH remained suppressed until 19 weeks of gestation. None of these women were clinically hyperthyroid. Thyroid antibodies were not found in most of them. Median birthweight in the infants of mothers who experienced weight loss of > 5% of their pre-pregnancy weight was lower compared with those of women who did not (P = 0.093). Five women were diagnosed with Graves' disease based on clinical features and thyroid antibody profile.
    CONCLUSIONS: In transient hyperthyroidism of hyperemesis gravidarum, thyroid function normalises by the middle of the second trimester without anti-thyroid treatment. Clinically overt hyperthyroidism and thyroid antibodies are usually absent. Apart from a non-significant trend towards lower birthweights in the infants of mothers who experienced significant weight loss, pregnancy outcome was generally good. Routine assessment of thyroid function is unnecessary for women with hyperemesis gravidarum in the absence of any clinical features of hyperthyroidism.
    Matched MeSH terms: Thyrotropin
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