Immunohistochemical Expression of Choline Acetyltransferase and Catecholamine-Synthesizing Enzymes in Head-and-Neck and Thoracoabdominal Paragangliomas and Pheochromocytomas.

Paragangliomas (PGLs) are neural-crest-derived, non-epithelial neuroendocrine tumors distributed along the parasympathetic and sympathetic nerves. Head-and-neck PGLs (HNPGLs) have been recognized as nonchromaffin, nonfunctional, parasympathetic tumors. By contrast, thoracoabdominal paragangliomas and pheochromocytomas (PPGLs) are chromaffin, functional, sympathetic tumors. Although HNPGLs and PPGLs have the same histological structure, the zellballen pattern, composed of chief and sustentacular cells surrounded by abundant capillaries, the pathobiological differences between these types of PGLs remain unclarified. To determine the phenotypic features of these PGLs, we performed an immunohistochemical study using specific antibodies against choline acetyltransferase (ChAT), an enzyme involved in acetylcholine synthesis, and enzymes for the catecholamine-synthesis, tyrosine hydroxylase (TH), and dopamine beta-hydroxylase (DBH), in 34 HNPGLs from 31 patients, 12 thoracoabdominal PGLs from 12 patients, and 26 pheochromocytomas from 22 patients. The expression of ChAT, TH, and DBH was 100%, 23%, and 10% in the HNPGLs; 12%, 100%, and 100% in the pheochromocytomas; and 25%, 67%, and 100% in the thoracoabdominal PGLs, respectively. These results designate HNPGLs as acetylcholine-producing parasympathetic tumors, in contrast to PPGLs being catecholamine-producing tumors. The other most frequently used neuroendocrine markers are synaptophysin and chromogranin A expressed 100% and 80%, respectively, and synaptophysin was superior to chromogranin A in HNPGLs. This is the first report of HNPGLs being acetylcholine-producing tumors. Immunohistochemistry of ChAT could be greatly useful for pathologic diagnosis of HNPGL. Whether measurement of acetylcholine levels in the blood or urine could be a tumor marker of HNPGLs should be investigated soon.

Graves' disease coexisted with resistance to thyroid hormone: a case report.

BACKGROUND: Resistance to thyroid hormone is a rare autosomal dominant disorder characterized by reduced responsiveness to thyroid hormone and can cause syndrome of inappropriate secretion of thyroid stimulating hormone. Although Graves' disease is a common autoimmune thyroid disorder, the coexistence of these two diseases is extremely rare and makes the diagnosis and treatment complicated, leading to the delayed diagnosis of resistance to thyroid hormone. We describe the case of a Japanese man with resistance to thyroid hormone coexisting with Graves' disease, in which the correct diagnosis of resistance to thyroid hormone was delayed by masking of the signs of syndrome of inappropriate secretion of thyroid stimulating hormone, with final diagnosis 30 years after the initial treatment for Graves' disease. CASE PRESENTATION: A 30-year-old Japanese man presented with diffuse goiter and thyrotoxicosis. Anti-thyroid stimulating hormone receptor antibody was positive. He was diagnosed with Graves' disease. Anti-thyroid medication was chosen as the initial treatment for Graves' disease. However, this treatment failed to normalize the free triiodothyronine, free thyroxine, and thyroid stimulating hormone levels. His thyroid hormone levels indicated syndrome of inappropriate secretion of thyroid stimulating hormone. After cessation of methimazole treatment by remission of Graves' disease, his state of syndrome of inappropriate secretion of thyroid stimulating hormone persisted. Magnetic resonance imaging revealed no pituitary tumor lesions. The results of thyroid stimulating hormone-releasing hormone stimulation test showed a normal response of thyroid stimulating hormone. He was suspected to have resistance to thyroid hormone. Direct sequencing analysis of the thyroid hormone receptor ß gene identified a heterozygous missense mutation, R282S. Coexistence of resistance to thyroid hormone with Graves' disease was confirmed. He has no signs of thyrotoxic symptoms, and is capable in activities of daily living at the present time. CONCLUSION: We described a rare case of resistance to thyroid hormone simultaneously existing with Graves' disease. This case demonstrated that these diseases can coexist, and indicated some of the difficulties in diagnosis of resistance to thyroid hormone with coexisting Graves' disease. The diagnosis of resistance to thyroid hormone did not become apparent until after anti-hyperthyroidism treatment. Although rare, careful follow-up after the initial treatment of Graves' disease is necessary. The coexistence of these two diseases should be considered in patients showing occasional syndrome of inappropriate secretion of thyroid stimulating hormone.

A case of mediastinal teratoma with pancreatic islets accompanied by discontinuation of insulin treatment in insulin-dependent diabetes mellitus.

A 74-year-old woman of insulin-dependent diabetes mellitus presented with gradually improvement of blood glucose control and finally discontinuation of insulin therapy, for some unknown reason. During follow-up period, she was admitted with hemoptysis. CT imaging showed a heterogeneous enhancement mass in the middle mediastinum with cyst and calcification, suggesting the diagnosis of mediastinal teratoma. Immediately after excision of the tumor, her plasma glucose levels again increased, and she required insulin therapy for glycemic control. Immunohistochemical examination showed that the tumor contained pancreatic tissue with both exocrine and endocrine components consisted with the islet cells of Langerhans with insulin-positive cells. Accordingly, we diagnosed insulin-producing mediastinal teratoma. Although hypoglycemic agents are the commonest cause of hypoglycemia in diabetic patients, an insulin-producing tumor should be considered in the patients who have dramatic improvement of diabetes mellitus, particularly after withdrawal of all hypoglycemic treatment. Mediastinal teratomas should be considered in differential diagnosis as etiology in undiagnosed case of hypoglycemia or blood glucose fluctuations.

Clinical remission of an inoperable malignant insulinoma by the combination treatment with octreotide and everolimus.

We report a 52-year-old woman with inoperable malignant insulinoma with multiple liver metastases. Histological examination of biopsy specimens from the pancreatic and hepatic lesions revealed pancreatic neuroendocrine tumor (pNET), G2. The tumor cells were positive for somatostatin receptor (SSTR) 2, 5, and the mammalian target of rapamycin (mTOR). Monthly intramuscular administration of octreotide LAR and once-daily oral administration of everolimus combination treatment markedly reduced the sizes of liver metastases, and hypoglycemia was well controlled. Combination treatment with somatostatin analog and mTOR inhibitor may be another effective approach in inoperable metastatic malignant insulinoma.

Heterogeneous nature of diabetes in a family with a gain-of-function mutation in the ATP-binding cassette subfamily C member 8 (ABCC8) gene.

Gain-of-function ATP-binding cassette subfamily C member 8 (ABCC8) mutations are known to cause neonatal diabetes mellitus and maturity-onset diabetes in the young. However, the intrafamilial heterogeneous nature of diabetes caused by the ABCC8 mutation is not fully understood to date. To clarify the intrafamilial heterogeneous nature of monogenetic diabetes, we conducted a case study on a family with ABCC8 mutations. We investigated eight family members, including a neonatal diabetes patient, based on metabolic features and genetic analysis. All coding exons and exon-intron boundaries of the KCNJ11, ABCC8, GCK, HNF1A, and HNF4A genes were amplified from genomic DNA and directly sequenced. Five gene mutation carriers with ABCC8 (c.1819G>A/p.V607M) were identified in this family, and the onset and severity of diabetes progressively worsened across the three generations. Each of the ABCC8 gene mutation carrier family members were diagnosed with diabetes as follows: the grandfather with type 2 diabetes at 35 years of age, the aunt with slowly-progressive insulin-dependent diabetes at 18 years of age, the mother with ketosis-onset insulin-dependent diabetes at 14 years of age, the sister with impaired glucose tolerance at 9 years of age, and the proband with transient neonatal diabetes at birth. The present study shows the heterogeneous nature of diabetes in a family with a gain-of-function mutation in the ABCC8 gene.

Pleiotropic effects of sitagliptin versus voglibose in patients with type 2 diabetes inadequately controlled via diet and/or a single oral antihyperglycemic agent: a multicenter, randomized trial.

PURPOSE: A step-up strategy for diet therapy and/or single oral antihyperglycemic agent (OHA) regimens has not yet been established. The aim of this study was to evaluate hemoglobin A1c (HbA1c) as a primary end point, and the pleiotropic effects on metabolic and cardiovascular parameters as secondary end points, of sitagliptin versus voglibose in patients with type 2 diabetes with inadequate glycemic control while on diet therapy and/or treatment with a single OHA. METHODS: In this multicenter, randomized, open-label, parallel-group trial, a total of 260 patients with inadequately controlled type 2 diabetes (HbA1c levels >6.9%) were randomly assigned to receive either sitagliptin (50 mg, once daily) or voglibose (0.6 mg, thrice daily) for 12 weeks. The primary end point was HbA1c levels. RESULTS: Patients receiving sitagliptin showed a significantly greater decrease in HbA1c levels (-0.78±0.69%) compared with those receiving voglibose (-0.30±0.78%). Sitagliptin treatment also lowered serum alkaline phosphatase levels and increased serum creatinine, uric acid, cystatin-C and homeostasis model assessment-ß values. Voglibose increased low-density lipoprotein-cholesterol levels and altered serum levels of several fatty acids, and increased Δ-5 desaturase activity. Both drugs increased serum adiponectin. The incidence of adverse events (AEs) was significantly lower in the sitagliptin group, due to the decreased incidence of gastrointestinal AEs. CONCLUSIONS: Sitagliptin shows superior antihyperglycemic effects compared with voglibose as a first-line or second-line therapy. However, both agents possess unique pleiotropic effects that lead to reduced cardiovascular risk in Japanese people with type 2 diabetes. TRIAL REGISTRATION NUMBER: UMIN 000003503.

Reversible impairment of the processing of proopiomelanocortin into ACTH in pituitary enlargement suspected of lymphocytic hypophysitis.

We describe a 64-year-old woman with a cystic pituitary mass presenting with central diabetes insipidus. Brain magnetic resonance imaging (MRI) with enhancement showed enlargement of the pituitary gland with cystic portions and thickening of the pituitary stalk with homogeneous enhancement. Combined anterior pituitary stimulation test and insulin-induced hypoglycemic test confirmed the diagnosis of panhypopituitarism, including adrenocortical insufficiency due to pituitary and hypothalamic dysfunction by stalk compression. Interestingly, the response of serum cortisol to CRH was low and delayed, in contrast to the marked increase in plasma ACTH. Molecular analysis of her plasma ACTH by Sephadex G75 gel exclusion chromatography coupled with radioimmunoassay (RIA) indicated a peak for high molecular weight ACTH, i.e., proACTH, in addition to that for 1-39 ACTH. Three years later, enlargement of the pituitary gland with cystic portions and thickening of the pituitary stalk disappeared completely, followed by the decrease in plasma proACTH level. By the results of endocrinological study and the change of pituitary MRI findings, lymphocytic hypophysitis was suggested. Synthesis of immature ACTH is generally thought to be due to impaired processing of the precursor proopiomelanocortin (POMC) through activation of prohormone convertase (PC)-1 by CRH. It is possible that the immature ACTH in this case was produced by impaired processing of the precursor POMC due to decreased CRH, dysfunction of corticotrophs in the anterior pituitary by compression of the normal pituitary, or antibodies targeting hypothalamic and/or pituitary cells. This report suggested that impaired processing of POMC may unusually play a role in adrenocortical insufficiency exhibited in lymphocytic hypophysitis.

Graves' disease associated with infectious mononucleosis due to primary Epstein-Barr virus infection: report of 3 cases.

Although the etiology of Graves' disease is still not clear, it is generally suggested that environmental factors such as infections contribute to the development of Graves' disease. We report here three cases of Graves' disease which presented simultaneously with infectious mononucleosis due to primary EBV infection. Acute EBV infection might play an important role in the onset of Graves' disease. These three women complained of a sore throat or neck pain, resembling subacute thyroiditis. In the case of thyrotoxicosis accompanied by sore throat or neck pain, Graves' disease must be distinguished from subacute thyroiditis.

Lymphocytic hypophysitis with a long latent period from onset of central diabetes insipidus to development of pituitary enlargement.

A 61-year-old man presented with central lymphocytic hypophysitis. Initial pituitary MRI imaging was normal, except for loss of the "bright spot" of the posterior lobe. A diagnosis of idiopathic diabetes insipidus was made. Two years later, pituitary gland enlargement with panhypopituitarism was detected. Eight months after commencing a replacement dose of corticosteroid, the pituitary enlargement was reduced in size. These findings resulted in a diagnosis of lymphocytic hypophysitis. In patients with idiopathic diabetes insipidus, it is important to suspect lymphocytic hypophysitis and to perform a long follow-up to repeat endocrinological examinations and pituitary imaging.

A rare case of diabetic mastopathy in a Japanese man with type 2 diabetes mellitus.

We report a case of diabetic mastopathy in a man with type 2 diabetes. The patient was a 62-year-old man who had been diagnosed with type 2 diabetes at the age of 46 years. He had been treated with oral hypoglycemic agents. He noticed a mass in his left breast in February 2007, when HbA(1)c was 7.6% with the treatment using oral hypoglycemic agents, including acarbose, glimepiride, buformine, and pioglitazone. Mammography of the breast showed increased density, and ultrasonography showed a regular-shaped hypoechoic mass. Core needle biopsy was performed, and diabetic mastopathy was confirmed pathologically. Diabetic mastopathy usually occurs in women with type 1 diabetes. This case, a man with type 2 diabetes, is very rare.

Tranilast, an antifibrogenic agent, ameliorates a dietary rat model of nonalcoholic steatohepatitis.

UNLABELLED: Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease and is one of the most common liver diseases in the developed world. The histological findings of NASH are characterized by hepatic steatosis, inflammation, and fibrosis. However, an optimal treatment for NASH has not been established. Tranilast, N-(3',4'-dimethoxycinnamoyl)-anthranilic acid, is an antifibrogenic agent that inhibits the action of transforming growth factor beta (TGF-beta). This drug is used clinically for fibrogenesis-associated skin disorders including hypertrophic scars and scleroderma. TGF-beta plays a central role in the development of hepatic fibrosis, and tranilast may thus ameliorate the pathogenesis of NASH. We investigated the effects of tranilast using an established dietary animal model of NASH, obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and nondiabetic control Long-Evans Tokushima Otsuka (LETO) rats fed a methionine-deficient and choline-deficient diet. Treatment with 2% tranilast (420 mg/kg/day) for 8 weeks prevented the development of hepatic fibrosis and the activation of stellate cells, and down-regulated the expression of genes for TGF-beta and TGF-beta-target molecules, including alpha1 procollagen and plasminogen activator-1. In addition, tranilast attenuated hepatic inflammation and Kupffer cell recruitment, and down-regulated the expression of tumor necrosis factor alpha. Unexpectedly, tranilast ameliorated hepatic steatosis and up-regulated the expression of genes involved in beta-oxidation, such as peroxisome proliferator-activated receptor alpha and carnitine O-palmitoyltransferase-1. Most of these effects were observed in LETO rats and OLETF rats, which suggest that the action of tranilast is mediated through the insulin resistance-independent pathway. CONCLUSION: Our findings suggest that targeting TGF-beta with tranilast represents a new mode of therapy for NASH.

Preclinical Cushing's syndrome resulting from adrenal black adenoma diagnosed with diabetic ketoacidosis.

A right adrenal tumor was incidentally discovered on abdominal computed tomography performed on a 53-year-old Japanese man, who had been hospitalized with diabetic ketoacidosis. Normal values were obtained for adrenal hormones in the morning after an overnight fast and urinary cortisol excretion after treatment of diabetic ketoacidosis with insulin. However, overnight dexamethasone administration with 1 mg or 8 mg did not completely suppress serum cortisol levels. There were no remarkable physical findings related to Cushing's syndrome. The patient was diagnosed as having preclinical Cushing's syndrome (PCS). Histological examination of the adrenalectomy specimen demonstrated adrenal black adenoma. Blood glucose levels subsequently improved after adrenalectomy, and the patient never developed adrenal insufficiency after hydrocortisone withdrawal. The patient was treated with diet therapy alone, and maintained good glycemic control. However, the patient still showed a diabetic pattern in an oral glucose tolerance test. It seems that the existence of PCS in addition to the underlying type 2 diabetes mellitus contributed to aggravation of blood glucose levels. Although there are many aspects of the natural course of PCS that have not been thoroughly elucidated, it is necessary to remain aware that a PCS patient with abnormal glucose metabolism may develop diabetic ketoacidosis by environmental agents.

Liver steatosis, but not fibrosis, is associated with insulin resistance in nonalcoholic fatty liver disease.

BACKGROUND: To address the hypothesis that liver steatosis causes systemic insulin resistance, we sought to determine the liver histological feature that most strongly contributes to insulin resistance in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: Liver biopsy specimens were obtained from 131 patients with clinically suspected NAFLD. The stage, grade of nonalcoholic steatohepatitis (NASH), and level of steatosis were scored and analyzed in relation to the homeostasis model assessment of insulin resistance (HOMA-IR) and the metabolic clearance rate (MCR), measured using the glucose clamp method. RESULTS: In the univariate analysis, the degree of hepatic steatosis (r = 0.458, P < 0.001), stage (r = 0.360, P < 0.001), and grade (r = 0.349, P < 0.01) of NASH were significantly correlated with the HOMA-IR. Multiple regression analysis adjusting for age, sex, body mass index, and each histological score showed that steatosis was significantly and independently associated with HOMA-IR (coefficient = 1.42, P < 0.001), but not with the stage (coefficient = 0.33, P = 0.307) or grade (coefficient = 0.67, P = 0.134) of NASH. Similar independent relationships were observed between steatosis and MCR, but the relationship was weaker (coefficient = -0.98, P = 0.076). CONCLUSIONS: Steatosis of the liver, but not the stage or the grade of NASH, is associated with insulin resistance in patients with NAFLD.

Insulin resistance accelerates a dietary rat model of nonalcoholic steatohepatitis.

BACKGROUND & AIMS: The increasing prevalence of nonalcoholic steatohepatitis (NASH) is due to the epidemic of obesity and type 2 diabetes, both of which are associated with insulin resistance. METHODS: To clarify the causal relationship between insulin resistance and the development of NASH, steatohepatitis was induced in obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) and nondiabetic control Long-Evans Tokushima Otsuka (LETO) rats by feeding them a methionine and choline-deficient (MCD) diet. Insulin sensitivity of the rats was altered by adding a high-fat (HF) diet or the peroxisomal-proliferator activated receptor-gamma agonist pioglitazone to the MCD diet. RESULTS: The MCD diet-induced steatohepatitis was accelerated in OLETF rats after 8 weeks. Steatosis preceded inflammation, which led to fibrosis and the development of steatohepatitis. The hepatic gene expression for transforming growth factor-beta, alpha1 procollagen and plasminogen activator inhibitor-1 was up-regulated in OLETF rats compared with LETO rats. The MCD + HF diet further enhanced insulin resistance and led to rapid development of pre-cirrhosis in OLETF rats by increasing the triglyceride pool, activating stellate cells, and up-regulating gene expression for sterol regulatory element-binding protein-1c and fatty acid synthase in the liver. In contrast, pioglitazone attenuated the MCD diet-induced steatohepatitis in OLETF rats but not in LETO rats by reversing the underlying pathogenesis involved in this model through improvement of insulin resistance. These results confirm a link between insulin resistance and the development/progression of steatohepatitis, at least partly via up-regulation of genes for lipogenesis, inflammation, and fibrogenesis, in animal models. CONCLUSIONS: Insulin resistance and/or diabetes may accelerate the entire pathologic spectrum of NASH.

Tranilast prevents the progression of experimental diabetic nephropathy through suppression of enhanced extracellular matrix gene expression.

The present study was performed to investigate the effects of the antiallergic drug tranilast on the development of diabetic nephropathy in streptozotocin (50 mg/kg)-induced diabetic spontaneously hypertensive rats (SHR). Diabetic SHR were given standard chow or chow containing tranilast at a dose of 1400 mg/kg for 24 weeks. The effects of tranilast on urinary albumin excretion, mesangial expansion, expression of transforming growth factor-beta (TGF-beta) and type I collagen mRNAs, number of anionic sites on the glomerular basement membrane (GBM), and urinary TGF-beta and 8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion were assessed. Tranilast did not affect the blood glucose concentration or blood pressure in diabetic SHR. Urinary albumin excretion rate and creatinine clearance were markedly increased in diabetic SHR. Tranilast treatment decreased albuminuria and hyperfiltration. Tranilast inhibited the diabetes-induced expansion of mesangial and tuft areas, as well as the increase in urinary TGF-beta and 8-OHdG excretion, loss of anionic sites of GBM, and overexpression of TGF-beta as determined immunohistochemically. The levels of TGF-beta and type I collagen mRNA expression were increased in the renal cortex in untreated diabetic SHR at 24 weeks, as determined by real-time quantitative polymerase chain reaction. Tranilast treatment inhibited the up-regulation of TGF-beta and type I collagen mRNA expression by 65 and 36%, respectively, in diabetic SHR. In conclusion, tranilast decreased albuminuria by suppressing glomerular hyperfiltration, mesangial expansion, and loss of the charge barrier via regulation of extracellular matrix gene expression and oxidative stress. Tranilast may be clinically useful in the treatment of diabetic nephropathy.

Prostaglandin E1 in lipid microspheres ameliorates diabetic peripheral neuropathy: clinical usefulness of Semmes-Weinstein monofilaments for evaluating diabetic sensory abnormality.

We investigated the effect of Prostaglandin E1 in lipid microspheres (Lipo-PGE1) on diabetic peripheral neuropathy from view of symptoms, neurological examinations including sensory threshold evaluated with Semmes-Weinstein monofilaments (SWM). Type 2 diabetic patients with diabetic peripheral neuropathy were participated in this study. The patients were randomly assigned to two groups, 11 Lipo-PGE1-treated patients and 16 control patients. Lipo-PGE1 at a dose of 10mg in 20ml of saline was injected intravenously as a bolus once daily for 2 weeks. Before and, 1, 2 and 4 weeks after the start of treatment with Lipo-PGE1, sensory threshold was evaluated with Semmes-Weinstein monofilaments at total 18 touch sites on the feet. Administration of Lipo-PGE1 improved subjective symptoms especially in items of numbness and imperception. Such improvement in subjective symptoms correlated well with the improvement in Semmes-Weinstein monofilaments examination, whereas the improvement was not recognized in motor nerve conduction velocity (MCV), sensory nerve conduction velocity (SCV) and coefficient variation of R-R interval on ECG (CVR-R). The improvement lasted for at least 6 months. This study demonstrated that Lipo-PGE1 has long term amelioration effects on diabetic neuropathy especially in symptoms and sensory threshold, and that Semmes-Weinstein monofilaments examination is a simpler, more valid and quantitative tool for assessing the clinical effect of Lipo-PGE1 on diabetic peripheral neuropathy.

A rotary shadow freeze-drying replica method for the three dimensional view of virus ultrastructure

A new rotary-shadowing process to obtain freeze-drying replicas is described for the analysis of virus ultrastructure, using the inner capsid of human rotavirus as a model. The findings corroborate the icosahedral symmetry with an arrangement pattern of capsomers of T=13L

Ultraestructura del espermatozoide de rata (Rattus norvegicus): aplicación de tres técnicas para microscopia eletrónica de transmisión / Ultrastructure of spermatozoa of rats (Rattus norvegicus): use of 3 technics in transmission electron microscopy

Se hizo un estudio ultraestructural del espermatozoide de rata tomado del tuvo seminífero, con microscopia electrónica de transmisión y mediante la aplicación de las técnicas de: secciones finas, microextendidos y réplicas. Los espermatozoides aislados y extendidos, presentan una cabeza de gran densidad electrónica, muy homogénea y ligeiramente curva en el extremo anterior; las secciones finas y longitudinales de esta zona corroboran lo compacto y homogéneo del DN, cubierto por las membranas nucleares y celular y por una pequeña cantidad de material acrosómico. A nivel de la pieza media, se observó los centríolos modificados en la pieza de unión o la cabeza y en los microtúbulos del flagelo. En secciones transversales y réplicas de éstas a nivel de la vaina mitocondrial se observan los 10 pares de microtúbulos y las 9 fibras densas, rodeadas por las mitocondrías que se disponen en forma ciruclar. En el segmento final de la cola, los microtúbulos conservan el arregalo de dos centrales y 9 pares de que los rodean