甲状旁腺腺瘤9例临床特点及延误诊断分析

目的探讨甲状旁腺腺瘤患者的临床特点和延误诊断的原因。方法回顾性分析2000年1月至2005年6月华中科技大学同济医学院协和医院收治的经手术确诊的9例甲状旁腺腺瘤患者的资料。结果9例中男性4例,女性5例。误诊时间8个月至11年。9例患者均有骨骼系统临床表现,同时兼有泌尿系统、消化系统表现者各有7例和6例。所有患者均有低血磷和血碱性磷酸酶升高,8例有高血钙和高尿钙。7例患者血清甲状旁腺素(PTH)明显升高。99m锝-甲氧基异丁基异腈(99mTc-MIBI)甲状旁腺显像是最佳定位检查。结论完整的病史,细致的体检和实验室检查对于甲状旁腺腺瘤的诊断十分重要。     

Decreased Histamine Catabolism in the Colonic Mucosa of Patients with Colonic Adenoma

Introduction Alterations in mucosal histamine degradation play an important role in various gastrotinestinal diseases including colonic adenoma. In humans, histamine can be catabolized either by oxidative deamination by diamine oxidase (DAO) or by ring methylation by histamine N-methyltransferase (HNMT). The significance of HNMT in this context was investigated for the first time in this project. Methods About 94 colonic biopsies were endoscopically obtained from 23 patients suffering from colonic adenoma and 26 biopsies from six healthy individuals. Each sample was mechanically homogenized, homogenates were cleared by centrifugation and used for determination of protein and histamine concentrations and enzyme activities of DAO and HNMT by radiometric assay. Results In adenoma patients DAO activities were slightly and HNMT activities were significantly decreased in normal mucosa compared to controls. Activities of both enzymes were significantly lower in adenoma tissue than in healthy mucosa in the same patients. A significant correlation was found between HNMT and DAO in all investigated samples. Histamine concentrations were elevated in adenoma patients. Conclusions Histamine catabolism is decreased in the colonic mucosa of patients with colonic adenoma.     

Pituitary abscess: our experience with a case and a review of the literature

Pituitary abscess is a rare disease. Due to its potentially high mortality and morbidity rate, it should be considered in the differential diagnosis of sellar masses. Despite recent advances in radiological investigations, making a definitive diagnosis preoperatively remains challenging. This 45-year-old Indian gentleman presented with severe throbbing headache for six months. Magnetic resonance imaging of the brain revealed a sellar mass with peripheral enhancement that was misdiagnosed as a pituitary macroadenoma. A trans-sphenoidal excision was done, which surprisingly yielded only pus that was drained accordingly from the lesion. Fungal and bacterial cultures were negative. However this patient subsequently lost complete function of the pituitary gland, resulting in central diabetes insipidus and required permanent hormonal replacement therapy in the deficient endocrine axes. A Medline search was conducted and a review of 24 cases reported in the last 5 years discussed.     

Genetic abnormalities of somatostatin receptors in pituitary tumors

Somatostatin exerts antisecretive and antiproliferative effects on different endocrine cells by acting through a family of G protein-coupled receptors that includes five subtypes (SST1-5). Normal human pituitary and pituitary adenomas have been shown to express almost all SST subtypes, with the exception of SST4. Consistent with the observation that octreotide and other somatostatin analogs bind to SST2 and SST5 with high affinity, these genes have been screened for quantitative/qualitative abnormalities in tumors removed from patients with poor responsiveness to somatostatin analogs treatment. Data obtained in GH-secreting adenomas suggested that resistance to octreotide was frequently associated with low expression of SST2 mRNA, although other authors failed to confirm this finding. To date, the only mutational change involving SST2 and SST5 is the Arg to Trp substitution in codon 240 of the SST5 gene that was found in one acromegalic patient resistant to octreotide. Similarly, loss of heterozygosis at SST5 gene locus in pituitary adenomas has been described in individual tumors. In recent years, molecular studies investigated the possible association of gene polymorphisms and susceptibility to diseases and/or resistance to drugs. As far as polymorphic variants of SST genes are concerned, a possible role of SST5 C1004T and T-461C alleles in influencing GH and IGF-I levels in patients with acromegaly has been proposed. Nevertheless, polymorphic variants in SST2 and SST5 genes seem to have a minor, if any, role in determining the different responsiveness to somatostatin analogs in patients with acromegaly.     

产妇产后垂体形态大小的变化

目的 探讨产妇产后垂体形态、大小及其MRI信号强度的变化规律.方法 选择自然分娩的产妇50例,分别于产后7 d及3、6、9个月时行垂体MRI检查,观察垂体形态,测量垂体体积及信号强度.结果 产后7 d产妇垂体饱满,上缘隆起,6个月时垂体上缘平直或略下陷;垂体平均体积产后7 d为548 mm3、3个月为526 mm3、6个月为518 mm3、9个月为516 mm3,7 d与3个月及3个月与6个月时相比,P均﹤0.05,而6个月与9个月时相比,P﹥0.05.垂体前叶与桥脑的相对信号强度在7 d与3个月及3个月与6个月时相比,P均﹤0.05,而6个月与9个月时相比,P﹥0.05. 结论 产妇产后垂体的体积逐渐减小,前叶信号强度逐渐减低,直至产后6个月.     

Acromegaly with Normal Growth Hormone Levels: Response to Sandostatin-LAR Treatment

We report a case of acromegaly with relatively low GH secretion in a patient with GH-secreting pituitary macroadenoma. The 44-year-old male patient presented with left temporal hemianopsia and characteristic acromegalic face, but had relatively low baseline and post-glucose GH levels. IGF-1 and IGFBP-1 were elevated. Transsphenoidal surgery did not achieve clinical or biochemiacl remission, and the patient still had elevated IGF-1 levels with low GH. Histological examination of the resected tumor revealed a pituitary adenoma stained weakly for GH. The patient was treated then with monthly injections of Sandostatin-LAR, with clinical improvement and suppression of IGF-I to the normal range. This is a rare case of acromegaly without elevated GH levels, and good response to treatment with somatostatin analog, as expected in classical GH-secreting pituitary adenomas.     

The effect of water temperature on the GABAergic and reproductive systems in female and male goldfish (Carassius auratus)

This study investigated the effect of water temperature on the synthesis of the amino acid neurotransmitter gamma-aminobutyric acid (GABA). In goldfish, GABA stimulates the release of pituitary gonadotropin-II (GTH-II), which regulates gonadal function. Fish were maintained in water of 11, 18, or 24 degrees. In the female and male goldfish, GABA synthesis rates estimated following inhibition of GABA catabolism by gamma-vinyl GABA (GVG) in both the telencephalon (TEL) and the hypothalamus (HYP) were increased in fish held at 24 degrees compared to those at either 11 or 18 degrees (P < 0.05). Additionally, GABA synthesis rates in the pituitary increased in a temperature-dependent manner. Glutamate is the precursor for GABA synthesis; however, no consistent pattern was seen between glutamate and GABA synthesis rates, indicating that glutamate is not a limiting factor in GABA synthesis. Both water temperature and GVG administration increased serum GTH-II levels in female goldfish. However, in male goldfish water temperature had no significant effect on serum GTH-II levels, and GVG injection increased serum GTH-II levels only in fish maintained at 24 degrees. The effects of temperature on the levels of mRNA expression of the GABA-synthesizing enzymes glutamate decarboxylase 65 (GAD(65)) and GAD(67) were measured by semiquantitative PCR. In the TEL and HYP of female goldfish, GAD(65) was not affected, whereas temperature change from 11 to 18 degrees increased (P < 0.05) GAD(67) mRNA levels. These results demonstrate that central GABAergic systems in the goldfish are temperature sensitive.     

The treatment of sporadic versus MEN1-related pituitary adenomas

The treatment of pituitary tumours strongly depends on their clinical presentation. In general, the treatment aims are reducing tumour volume and/or decreasing hormone hypersecretion. It relies on single or a combination of three different methods: surgery, medication and radiotherapy. The rationale for deciding the treatment are many but include the aggressiveness of the tumour. The aetiologies of sporadic pituitary adenomas are not fully understood. However, several causes have been identified resulting in specific familial phenotypes like multiple endocrine neoplasia type I (MEN1). MEN1 is related to mutations in the MEN1 gene, a tumour suppressor gene localized on chromosome 11q13 and which encodes menin, a 610 amino acid protein. During the last years, an evidence progressively emerged that MEN1-related adenomas were more aggressive and less responsive to therapy than their sporadic counterparts. In this article, we review the differences between sporadic and MEN1-related adenomas and suggest specific ways of treatment and follow-up for MEN1-related tumours.     

Morphological Characterization and Subtyping of Silent Somatotroph Adenomas

GH-producing adenomas clinically are endocrine-active tumors accompanied with acromegaly in most instances. However, GH-producing adenomas apparently unassociated with acromegaly, or so-called silent somatotroph adenomas (SSA), have recently been reported but rarely. The reported cases are characterized by normal or slightly elevated serum levels of GH but without acromegaly. Tumor cells contain moderate, trace or no GH immunoreactivity. We experienced 7 cases of SSA which were not always similar in morphology and pathogenetic mechanism. They could be further divided into the following 3 subtypes. Subtype 1 (N = 2): a moderate number of cells were immunopositive for GH, and GH mRNA was also expressed in moderate or numerous cells. Densely granulated cells were noted. It is assumed that inhibition of hormone release into circulation. Subtype 2 (N = 3): a small number of cells were immunopositive for GH, while GH mRNA was expressed in numerous tumor cells. They were sparsely granulated cells containing fibrous bodies. These findings suggest that posttranslational processing of the gene product may be defective. Subtype 3 (N = 2): Only a scattered number of cells were immunopositive for GH and GH mRNA was co-localized in immunopositive cells. They were sparsely granulated cells containing poorly developed organelles that did not resemble those of typical sparsely granulated GH cells. The findings indicate that adenoma cells are largely immature with minimal GH lineage differentiation.