成年期甲状腺功能减退症大鼠额叶突触结合蛋白I表达及T4替代治疗作用

目的 观察成年期甲状腺功能减退症(甲减)大鼠额叶突触结合蛋白I(synaptotagmin I,sytI)表达改变及不同剂量甲状腺素替代治疗的作用.方法 将44只大鼠按体质量随机分为甲减组、常规治疗组、大剂量治疗组、对照组,用丙基硫氧嘧啶(PTU)腹腔注射建立成年期大鼠甲减及治疗模型;放射免疫法测定4组大鼠血清甲状腺激素水平,免疫组织化学S-P法分析sytI蛋白在4组大鼠额叶分子层、外颗粒层、外锥体细胞层、内颗粒层、内锥体细胞层中的表达.结果 甲减组大鼠血清T3、T4[(0.34±0.04)、(43.01±2.95)nmol/L]显著低于对照组[(0.65±0.15)、(55.20±3.56)nmol/L,F值分别为6.026、4.503,P<0.05或<0.01],甲减组鼠syt I免疫反应产物在额叶分子层(0.018±0.010)、外颗粒层(0.020±0.007)、外锥体细胞层(0.013±0.008)、内颗粒层(0.011±0.005)、内锥体细胞层(0.024±0.013)均较对照组(0.028±0.010、0.031±0.010、0.028±0.010、0.022±0.008、0.038±0.013)明显减少(F值分别为5.697、8.965、14.668、13.597、6.807,P<0.05或<0.01).常规治疗组大鼠血清T3、T4[(0.63±0.05)、(55.04±3.77)nmoL/L]与对照组比较,差异无统计学意义(F值分别为3.162、0.367,P均>0.05),额叶分子层、外颗粒层、外锥体细胞层、内颗粒层、内锥体细胞层syt I蛋白表达(0.027±0.013、0.025±0.009、0.022±0.008、0.020±0.010、0.033±0.010)与对照组比较差异均无统计学意义(F值分别为0.094、2.208、2.467、0.350、0.693,P均>0.05);大剂量治疗组大鼠血清T3、T4[(1.11±0.10)、(96.68±6.42)nmol/L]显著高于对照组(F值分别为6.291、12.031,P均<0.01),额叶各层syt I蛋白表达(0.028±0.008、0.031±0.011、0.026±0.012、0.023±0.011、0.038±0.010)与对照组比较的差异均无统计学意义(F值分别为0.001、0.019、0.111、0.061、0.001,P均>0.05).结论 成年期甲减大鼠额叶内syt I蛋白表达减少,常规剂量甲状腺素替代治疗就能使其恢复至正常水平.     

成年期甲状腺功能减退症大鼠额叶突触结合蛋白I表达及T4替代治疗作用

Objective To observe the expression of synaptotagmin I(syt I)protein in the prefrontal cortex of adult-onset hypothyroidism rats and the effects of replicated therapy in different doses of thyroid hormone on the syt I protein.Methods All 44 aduh male Sprague-Dawley rats were divided into 4 groups randomly according to their body mass:hypothyroidism group,routine dosage thyroxine treatment group,high dosage thyroxine treatment group and control group.The adult male Sprague-Dawley rats were replicated to the adult-onset hypothyroidism and treatment models with propyhhiouracil(PTU).The levels of serum T3,T4 were assayed by the radioimmunoassay method and the level of the syt I protein in the molecular layer,external granular layer,external pyramidal layer,internal granular layer and internal pyramidal layer in prefrontal cortex was analyzed by immunohistochemistry.Results In the hypothyroidism group,the levels of serum T3 and T4[(0.34±0.04),(43.01±2.95)nmol/L]were significantly lower than those in the control group[(0.65±0.15), (55.20±3.56)nmol/L, F value: 6.026,5.940,4.503,P<0.05 or <0.01 ], the levels of the syt I protein in the molecular layer(0.018±0.010), external granular layer (0.020±0.007), external pyramidal layer(0.013±0.008), internal granular layer(0.011±0.005), internal pyramidal layer(0.024±0.013) of prefrontal lobe were significantly lower compared to the control group[(0.028±0.010,0.031 ± 0.010,0.028 ± 0.010,0.022 ± 0.008,0.038 ± 0.013), F value: 5.697,8.965,14.668,13.597,6.807,P<0.05 or <0.01 ]. In the routine dosage of the thyroxine treatment group, the levels of serum T3,T4 [(0.63 ±0.05), (55.04 ± 3.77)nmol/L] were not significantly different compared to the control group(F value: 3.162,0.367,all P>0.05), and the level of the syt I protein in the molecular layer, external granular layer, external pyramidal layer, internal granular layer and internal pyramidal layer in prefrontal cortex showed a significant improvement of the syt I protein(0.027 ± 0.013,0.025 ± 0.009,0.022 ± 0.008,0.020 ± 0.010,0.033 ± 0.010), which were similar to that of the control group(F value: 0.094,2.208,2.467,0.350,0.693, all P>0.05). In the high dosage thyroxine thyroid hormone treatment group, the levels of serum T3 and T4[ (1.11 ± 0.10), (96.68 ± 6.42)nmoL/L] were higher than the control group(F value: 6.291,12.031, all P<0.01), the expression of the syt I protein(0.028 ± 0.008,0.031 ±0.011,0.026 ± 0.012,0.023 ± 0.011,0.038 ± 0.010) were not significantly different compare to the control group (F value: 0.001,0.019,0.111,0.061,0.001, all P>0.05). Conclusions The expression of the syt I protein in the prefrontal cortex of adult-onset hypothyroidism can be decreased, which can be reversed by routine dosage of thyroxine treatment.     

成年期甲状腺功能减退症大鼠额叶突触结合蛋白I表达及T4替代治疗作用

Objective To observe the expression of synaptotagmin I(syt I)protein in the prefrontal cortex of adult-onset hypothyroidism rats and the effects of replicated therapy in different doses of thyroid hormone on the syt I protein.Methods All 44 aduh male Sprague-Dawley rats were divided into 4 groups randomly according to their body mass:hypothyroidism group,routine dosage thyroxine treatment group,high dosage thyroxine treatment group and control group.The adult male Sprague-Dawley rats were replicated to the adult-onset hypothyroidism and treatment models with propyhhiouracil(PTU).The levels of serum T3,T4 were assayed by the radioimmunoassay method and the level of the syt I protein in the molecular layer,external granular layer,external pyramidal layer,internal granular layer and internal pyramidal layer in prefrontal cortex was analyzed by immunohistochemistry.Results In the hypothyroidism group,the levels of serum T3 and T4[(0.34±0.04),(43.01±2.95)nmol/L]were significantly lower than those in the control group[(0.65±0.15), (55.20±3.56)nmol/L, F value: 6.026,5.940,4.503,P<0.05 or <0.01 ], the levels of the syt I protein in the molecular layer(0.018±0.010), external granular layer (0.020±0.007), external pyramidal layer(0.013±0.008), internal granular layer(0.011±0.005), internal pyramidal layer(0.024±0.013) of prefrontal lobe were significantly lower compared to the control group[(0.028±0.010,0.031 ± 0.010,0.028 ± 0.010,0.022 ± 0.008,0.038 ± 0.013), F value: 5.697,8.965,14.668,13.597,6.807,P<0.05 or <0.01 ]. In the routine dosage of the thyroxine treatment group, the levels of serum T3,T4 [(0.63 ±0.05), (55.04 ± 3.77)nmol/L] were not significantly different compared to the control group(F value: 3.162,0.367,all P>0.05), and the level of the syt I protein in the molecular layer, external granular layer, external pyramidal layer, internal granular layer and internal pyramidal layer in prefrontal cortex showed a significant improvement of the syt I protein(0.027 ± 0.013,0.025 ± 0.009,0.022 ± 0.008,0.020 ± 0.010,0.033 ± 0.010), which were similar to that of the control group(F value: 0.094,2.208,2.467,0.350,0.693, all P>0.05). In the high dosage thyroxine thyroid hormone treatment group, the levels of serum T3 and T4[ (1.11 ± 0.10), (96.68 ± 6.42)nmoL/L] were higher than the control group(F value: 6.291,12.031, all P<0.01), the expression of the syt I protein(0.028 ± 0.008,0.031 ±0.011,0.026 ± 0.012,0.023 ± 0.011,0.038 ± 0.010) were not significantly different compare to the control group (F value: 0.001,0.019,0.111,0.061,0.001, all P>0.05). Conclusions The expression of the syt I protein in the prefrontal cortex of adult-onset hypothyroidism can be decreased, which can be reversed by routine dosage of thyroxine treatment.     

甲状腺素对甲状腺功能减退症大鼠海马syntaxin-1蛋白表达的影响

目的 研究成年期甲状腺功能减退症(简称甲减)大鼠海马突触前膜蛋白syntaxin-1的表达及不同剂量甲状腺素替代治疗的作用,探讨甲减脑损伤可能的分子机制.方法 健康3月龄成年SD雄性大鼠44只,体质量250 ～ 300 g,按体质量随机分为4组:甲减组、常规治疗组、大剂量治疗组和对照组,每组11只.甲减组、常规治疗组和大剂量治疗组每日腹腔注射丙基硫氧嘧啶(PTU) 10 mg/kg;4周后,甲减组继续给予PTU腹腔注射2周,常规治疗组和大剂量治疗组每日分别给予50、200μg/kg左旋甲状腺素腹腔注射2周;对照组每日腹腔注射等量生理盐水.造模结束后,采用放射免疫法检测4组大鼠血清T3、T4水平;采用免疫组化法检测4组大鼠海马syntaxin-1蛋白的表达.结果 与对照组[(0.65±0.05)、(55.20±3.56)nmol/L]比较,甲减组血清T3、T4[(0.34±0.04)、(43.01±2.95)nmol/L]明显降低(P均＜0.05),大剂量治疗组血清T3、T4[(1.11±0.10)、(96.68±6.42)nmol/L]显著升高(P均＜0.05);常规治疗组血清T3、T4[(0.63±0.05)、(55.04±3.77)nmol/L]与对照组比较,差异无统计学意义(P均＞0.05).甲减组大鼠海马CA1、CA3区起始层、放射层、腔隙层和齿状回(DG)分子层、多形层syntaxin-1蛋白表达水平(0.059±0.016、0.064±0.014、0.068±0.016,0.069±0.017、0.072±0.016、0.070±0.011,0.051±0.012、0.072±0.017)显著高于对照组(0.037±0.008、0.045±0.010、0.042±0.009,0.040±0.010、0.053±0.009、0.042±0.009,0.032±0.007、0.047±0.010,P均＜0.05);常规治疗组和大剂量治疗组各层syntaxin-1蛋白表达水平(0.041±0.011、0.046±0.017、0.044±0.014,0.037±0.008、0.051±0.010、0.043±0.010,0.033±0.011、0.045±0.014和0.040±0.010、0.045±0.011、0.043±0.010,0.033±0.009、0.050±0.010、0.041±0.009,0.032±0.009、0.046±0.009)较甲减组降低(P均＜ 0.05),与对照组比较,差异无统计学意义(P均＞0.05).结论 成年期甲减大鼠海马内syntaxin-1蛋白表达增加,常规剂量甲状腺素替代治疗能使其恢复至正常水平.     

突触体素在甲状腺功能减退大鼠脑海马发育期的表达

探讨甲状腺激素对发育关键期大鼠海马各区突触体素表达的作用和影响,结果提示在脑发育关键期,甲状腺激素水平的减少改变了海马各区突触体索mRNA的表达和时相性,进而影响了该区域突触的发生及相关神经回路的建立。     

甲状腺功能减退症的诊治

甲状腺功能减退症（甲减）是由多种原因引起的甲状腺激素合成、分泌或生物效应不足所致的一种全身代谢减低综合征。原发性甲减是其中最常见的类型,主要由自身免疫甲状腺炎如桥本病所致,其他原因包括由于中枢促甲状腺激素释放激素（TRH）或促甲状腺激素（TSH）不足、甲状腺手术或放射性碘治疗导致的甲减。甲状腺激素的测定,包括TSH和游离甲状腺素（FT4）等,是甲减诊断的主要手段。甲减的诊断可分为临床（TSH高,FT4低）或亚临床甲减（TSH高,FT4正常）。甲减治疗的目的是纠正甲状腺功能不足,减轻症状,避免进展至粘液性水肿。甲减通常采用合成的左甲状腺素治疗。尽管典型甲减的诊断、治疗在临床上较为简单,但有相当部分患者治疗并未达到最优化,即使甲状腺功能指标正常仍感觉生活质量较差。本文简述了甲减的病因、分类、诊断和治疗。对部分患者治疗效果不佳的可能原因及优化措施亦进行了讨论。     

新生儿先天性甲状腺功能减退症的筛查及临床分析

目的：开展新生儿先天性甲状腺功能减退症（CH）的筛查及临床治疗,以期降低残疾儿童的发生率,提高我国人口素质,方法：应用国际先进的时间分辨荧光免疫法（Tr-FIA)检测新生儿滤纸干血片上TSH的[浓度筛查CH;且对筛查阳性的患儿进行临床分析。结果：筛查新生儿315 472例,确诊CH者66例,包括47例典型甲减,19例亚临床甲减,筛查阳性率为1／4 780,47例典型病例最终诊断为永久性甲减的41例,暂时性甲减2例,2例未满2岁未再作重新评估,1例因其他原因夭折,1例放弃,19例亚临床型病例最终诊断永久性甲减7例,暂时性甲减4例,商TSH血症5例,有3例未满2岁未再作重新评估,随访患儿目前体格及智力发育皆正常,结论：Tr-FIA法是筛查CH十分理想的非放射性免疫分析技术,筛查阳性的CH患儿,包括甲减和亚临床甲减病例,都应给以及时合理剂量甲状腺素治疗,是否终身治疗则需要根据2岁及5岁的重新评估作出决定。     

甲状腺激素对成年大鼠海马内突触结合蛋白Ⅰ表达的影响

目的 观察不同甲状腺激素水平对大鼠海马突触结合蛋白Ⅰ(syt Ⅰ)蛋白表达水平的影响.方法 复制雄性SD大鼠成年期甲状腺功能减退症(甲减)、甲状腺功能亢进症(甲亢)模型,用放射免疫法测定血清甲状腺激素T3、T4水平,用免疫组织化学超敏链霉菌抗生物素蛋白-过氧化物酶连结(S-P)法分析海马CA1区、CA3区和齿状回(DG)Syt Ⅰ蛋白的表达.结果 甲减组大鼠血清T3、T4水平[(0.34±0.12)、(41.03±11.37)nmol/L]明显低于对照组[(0.65±0.15)、(55.20±10.68)nmol/L,P<0.01或<0.05];甲减组Syt Ⅰ免疫反应产物阳性颗粒较对照组也明显减少,尤以海马CA1、CA3区锥体细胞层、放射层及DG区颗粒细胞层减少明显,Syt Ⅰ免疫反应产物,甲减组海马CA1区多形层(0.048±0.007)、细胞层(0.299±0.035)、放射层(0.042±0.007)、腔隙分子层(0.038±0.006)和CA3区的细胞层(0.085±0.019)、放射层(0.040±0.011)、腔隙分子层(0.038±0.006)及DG区颗粒细胞层(0.076±0.019)均较对照组(0.068±0.014、0.376±0.053、0.053±0.008、0.056±0.009,0.118±0.026、0.052±0.010、0.053±0.009、0.099±0.015)明显减少(P<0.01或<0.05).甲亢组大鼠血清T3、T4水平[(1.43±0.30)、(157.18±19.95)nmol/L]明显高于对照组(P<0.01).CA1区细胞层(0.322±0.050)、放射层(0.039±0.006)、腔隙分子层(0.042±0.006)和CA3区细胞层(0.098±0.034)、放射层(0.046±0.013)、腔隙分子层(0.046±0.010)及DG区颗粒层(0.085±0.024)、分子层(0.042±0.009)Syt Ⅰ免疫反应产物也较对照组减少(P<0.05或<0.01).结论 甲状腺激素水平增高或降低均可导致成年大鼠海马内SytⅠ蛋白表达减少.     

亚临床甲状腺功能减退症的治疗

亚临床甲状腺功能减退症(亚甲减)以基线促甲状腺激素(TSH)水平升高和血清游离甲状腺素水平正常为特征，亚临床或隐匿性甲减常常反映甲状腺激素分泌的缺陷。甲状腺破坏性治疗(甲状腺次全切除术或放射碘治疗)或颈部广泛放射治疗后的亚临床甲减应开始使用左甲状腺素(L-T4)治疗；妊娠和哺乳期的亚甲减也应使用L-T4治疗。其他早期使用甲状腺激素替代治疗的指征包括TSH水平升高以及抗甲状腺过氧化物酶(TPO)抗体阳性，因为这些患者的亚甲减很可能进展为临床甲减。提示存在甲状腺激素相对缺乏的I临床体征和症状的所有患者都应该试用L-T4替代治疗，这些患者包括亚临床甲减并发不孕、抑郁症或其他神经心理异常。单纯血清TSH水平升高或高胆固醇血症不是L-T4治疗的适应症，除非患者有甲状腺疾病史以及提示甲状腺激素缺乏的临床症状。     

亚临床甲状腺功能减退症与血脂异常关系研究

目的探讨亚临床甲状腺功能减退症(亚临床甲减)患者促甲状腺素(TSH)与血脂水平的关系。方法回顾性分析2006年1月至2010年1月北京协和医院病案数据库中诊断为亚临床甲减且未经治疗的患者50例,以及年龄和性别相匹配的社区查体人群250名,收集常见心血管危险因素及甲状腺功能水平资料,多元回归探讨TSH水平对血脂水平的影响。结果在常见心血管危险因素控制良好的情况下,TSH水平与三酰甘油(TG)、HDL-C和LDL-C呈正相关(均为P<0.05);与查体人群相比,亚临床甲减可显著影响TG水平,在TSH≥10.0 mIU/L时,TSH水平与LDL-C升高呈正相关(P=0.044)。结论亚临床甲减可能是血脂异常的高危因素之一,临床实践中应重视该疾病的研究、诊断和治疗,当TSH≥10.0mIU/L时应考虑积极替代治疗。     

甲状腺激素与妊娠

本文复习了妇女妊娠期甲状腺功能的变化，以及胎儿甲状腺功能的发育并介绍了对妊娠并发甲状腺功能亢进症或甲状腺功能减退症的处理原则。     

Effect of thyroxine on SNARE complex and synaptotagmin-1 expression in the prefrontal cortex of rats with adult-onset hypothyroidism

Thyroid hormone insufficiency in adulthood causes a wide range of brain impairments, including altered synaptic proteins in the prefrontal cortex (PFC). The present study investigated whether adult-onset hypothyroidism altered the expression of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes and synaptotagmin-1 (syt-1) in the PFC of rats. Sprague-Dawley rats were randomly divided into 4 groups: control, hypothyroid, and hypothyroid treated with T(4) [5 or 20 μg/100 g body weight (BW)]. Adult-onset hypothyroidism was induced in rats with the antithyroid drug 6-n-propyl-2-thiouracil (ip injection). PFC levels of synaptosomal-associated protein of 25 kDa (SNAP-25), syntaxin-1, vesicle-associated membrane protein 2 (VAMP-2) and syt-1 were determined by immunohistochemistry and western blot analyses. The results showed that syntaxin-1 and syt-1 were expressed at significantly lower levels in hypothyroid rats, VAMP-2 levels were not altered, and SNAP-25 levels were much higher compared to controls. A 2-week treatment with 5 μg T(4)/100 g BW partially normalized levels of SNARE complex and syt-1, and 20 μg T(4)/100 g BW restored these proteins closer to normal levels. Our findings indicate that dysregulation of SNARE complex and syt-1 in PFC of adult-onset hypothyroidism can be restored by T(4) treatment.     

甲状腺激素对大鼠小脑,海马,嗅脑神经元型一氧化氮合酶基因表达的调节

目的　观察 15日龄大鼠小脑 ,海马 ,嗅脑一氧化氮 (NO)含量 ,一氧化氮合酶 (NOS)活性的变化及甲状腺激素对上述部位神经元型一氧化氮合酶 (nNOS)基因表达的调节。方法　采用丙基硫氧嘧啶 (PTU)给孕母鼠灌胃造成仔鼠甲减动物模型 ;采用NO ,NOS生化测定法及nNOSmRNA半定量逆转录聚合酶链反应 (RT PCR)法。结果　无论正常组还是甲减组 ,NO含量 ,NOS活性及nNOSmRNA转录均以小脑为最高 ,嗅脑次之 ,海马最低 (P <0 .0 5 ) ;正常组NO含量 ,NOS活性nNOSmRNA转录均高于甲减组 (P <0 .0 1)。结论　提示甲状腺激素对nNOS基因表达有上调作用 ,NO信号系统可能参与大鼠小脑 ,海马 ,嗅脑等区甲状腺激素缺乏所造成的脑损害过程。     

Thyroid hormone replacement and growth of children with subclinical hypothyroidism and diabetes

Growth potential among people with Type 1 diabetes and subclinical hypothyroidism may be significantly reduced. Growth was evaluated in 25 children with diabetes who had thyromegaly and elevated thyrotrophin (TSH) levels. All patients appeared clinically euthyroid except for four with short stature. Basal growth rate was significantly lower (p less than 0.005) in Group 1 (TSH greater than 50 mU l-1) and Group 2 (TSH level 10.1-50 mU l-1) than in patients with TSH levels between 5 and 10 mU l-1 (Group 3) or control diabetic children. Serum thyroxine (T4) levels were significantly lower (p less than 0.05) in Group 1 than in Groups 2 or 3. Significant improvement in growth velocity after thyroxine treatment was observed in Group 1 patients compared with those in Groups 2 or 3 (p less than 0.05). More prepubertal test children demonstrated improved growth after beginning thyroxine compared with matched diabetic controls (p less than 0.02). Postpubertal subjects treated with thyroxine did not show significant differences in growth velocity compared with controls. Z-scores for height were not different (p greater than 0.05; ANOVA) between control and test patients for any of the groups. Early detection of subclinical hypothyroidism by thyromegaly, reduced growth velocity, and elevated TSH levels, with institution of thyroxine treatment, can improve growth in prepubertal diabetic children.     

甲状腺功能减退对成年小鼠空间学习记忆及海马神经颗粒素表达的影响

目的观察甲状腺功能减退对成年雄性昆明小鼠空间学习记忆功能及海马内神经颗粒素（Ng）表达的影响。方法将成年雄性昆明小鼠随机分为对照组、丙硫氧嘧啶（PTU）组、PTU＋T4（甲状腺素）组。对照组饮用自来水，PTU和PTU＋T4组饮用含0．1％PTU水。6周后，PTU＋T4组腹腔注射T4（20μg·kg^-1·d^-1），连续2周。Morris水迷宫观察小鼠的空间学习记忆能力，免疫组化分析海马各亚区Ng蛋白的表达。结果PTU组小鼠体质量、血清B、T4显著低于对照组（P〈0．05）；水下平台的潜伏期明显长于对照组（P〈0．05）；Ng蛋白表达水平海马CA1区（6．61±1．25）和齿状回DG区（6．40±0．94）低于对照组（8．91±1．08、8．82±1．23，P〈0．05）。T4替代治疗后，上述各项检查与对照组比较，差异无统计学意义（P〉0．05）。结论甲状腺功能减退可逆性损害成年雄性小鼠空间学习记忆功能，其机制可能与CA1和DG区Ng蛋白表达减少有关。     

Thyroid hormone use, hyperthyroidism and mortality in older women

Purpose

Thyroid dysfunction is common, particularly among older women. The safety of thyroid hormone use and long-term prognosis of hyperthyroidism remain controversial. We performed a prospective cohort study to examine the relationship among thyroid hormone use, previous hyperthyroidism, abnormal thyroid function, and mortality.

Methods

We studied 9449 community-dwelling white women aged ≥65 years followed for 12 years. For analyses of thyroid function, we performed a nested case-cohort in 487 women using a third-generation thyroid-stimulating hormone assay. Causes of death were adjudicated based on death certificates and hospital records.

Results

Twelve percent of the 9449 women took thyroid hormone at baseline, and the mean duration of thyroid hormone use was 15.8 years; 9.4% of participants reported a history of hyperthyroidism. During 12 years of follow-up, 3159 women died (33%). In multivariate analysis, mortality among users of thyroid hormone was similar to that observed for nonusers (relative hazard [RH] 1.11, 95% confidence interval [CI], 0.98-1.24, P = .09). Previous hyperthyroidism was associated with a higher risk of all-cause mortality (RH 1.20, 95% CI, 1.06-1.36), particularly cardiovascular mortality (RH 1.46, 95% CI, 1.20-1.77). Low (≤0.5 mU/L) or high (>5 mU/L) thyroid-stimulating hormone levels were not associated with excess total or cause-specific mortality, but the power to detect these relationships was limited.

Conclusions

Among older women, thyroid hormone use is not associated significantly with excess mortality, but previous hyperthyroidism may be associated with a small increase in all-cause and cardiovascular mortality. Additional long-term studies of hyperthyroidism and its treatment should further explore these findings.     

Thyroid peroxidase antibodies, levels of thyroid stimulating hormone and development of hypothyroidism in euthyroid subjects

ObjectiveThyroid peroxidase antibodies (TPOAbs) have been found to be related to the levels of thyroid stimulating hormone (TSH) and to predict future development of thyroid failure in selected populations. We investigated these relations in a euthyroid general population.DesignCross-sectional investigation of the relationship of TPOAbs and levels of TSH in euthyroid subjects. Prospective investigation of the association of TPOAbs and TSH with development of hypothyroidism. Incident hypothyroidism was defined as initiation of l-thyroxine in the absence of thyreostatic medication.SubjectsThe study was performed in a random sample of 2703 participants of the PREVEND study. A total of 309 subjects were excluded from analyses, mainly because of TSH outside the reference range (0.35–4.94 mIU/l; n = 115).ResultsMean (SD) baseline age was 47.7 (12.5) years, with 50.8% females. Prevalence of positive TPOAbs (≥ 12 kU/l) was 8.4%. TSH concentrations were increased in subjects with TPOAbs (P < 0.001). During a median follow-up of 9.1 years, 15 (0.6%) subjects developed hypothyroidism (3.5% in TPOAbs positive vs. 0.4% in TPOAbs negative subjects; P < 0.001). Female sex (P = 0.02), and TSH (P < 0.001) were also significantly associated with incident hypothyroidism. In multivariate analysis, TSH and TPOAbs remained independent predictors (both P < 0.001).ConclusionsWe confirmed the positive relationship of the presence of TPOAbs with levels of TSH and showed that TPOAbs and TSH predict future development of hypothyroidism. These results are consistent with the presence of TPOAbs necessitating a compensatory increase in levels of TSH for maintenance of euthyroidism, even in the euthyroid range.     

继发性甲状腺功能减退患儿垂体-甲状腺激素改变及治疗探讨

探讨继发于伞垂体功能减退的甲状腺功能减退(继发性甲减)患儿的激素改变及治疗.测定1999年9月至2006年3月以生长迟缓就诊于山东省市医院儿科的57例继发性甲减患儿垂体-靶腺激素,同时观察激素替代治疗的合适剂量.57例继发性甲减患儿FT_4均降低,初诊时19例(33.3%)TSH低于正常,38例(66.7%)TSH正常或略高,但L-T_4有效治疗后55例(96.5%)TSH低于正常.57例患儿均伴有生长激素缺乏及垂体MRI影像异常.继发性甲减常伴有全垂体功能减退和MRI异常,其治疗目标应使FT_4尽快达到并维持在正常上限.