Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
J Pathol Inform ; 4: 24, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24244882

RESUMEN

BACKGROUND: Recent advances in information technology have allowed the development of a telepathology system involving high-speed transfer of high-volume histological figures via fiber optic landlines. However, at present there are geographical limits to landlines. The Japan Aerospace Exploration Agency (JAXA) has developed the "Kizuna" ultra-high speed internet satellite and has pursued its various applications. In this study we experimented with telepathology in collaboration with JAXA using Kizuna. To measure the functionality of the Wideband InterNet working engineering test and Demonstration Satellite (WINDS) ultra-high speed internet satellite in remote pathological diagnosis and consultation, we examined the adequate data transfer speed and stability to conduct telepathology (both diagnosis and conferencing) with functionality, and ease similar or equal to telepathology using fiber-optic landlines. MATERIALS AND METHODS: We performed experiments for 2 years. In year 1, we tested the usability of the WINDS for telepathology with real-time video and virtual slide systems. These are state-of-the-art technologies requiring massive volumes of data transfer. In year 2, we tested the usability of the WINDS for three-way teleconferencing with virtual slides. Facilities in Iwate (northern Japan), Tokyo, and Okinawa were connected via the WINDS and voice conferenced while remotely examining and manipulating virtual slides. RESULTS: Network function parameters measured using ping and Iperf were within acceptable limits. However; stage movement, zoom, and conversation suffered a lag of approximately 0.8 s when using real-time video, and a delay of 60-90 s was experienced when accessing the first virtual slide in a session. No significant lag or inconvenience was experienced during diagnosis and conferencing, and the results were satisfactory. Our hypothesis was confirmed for both remote diagnosis using real-time video and virtual slide systems, and also for teleconferencing using virtual slide systems with voice functionality. CONCLUSIONS: Our results demonstrate the feasibility of ultra-high-speed internet satellite networks for use in telepathology. Because communications satellites have less geographical and infrastructural requirements than landlines, ultra-high-speed internet satellite telepathology represents a major step toward alleviating regional disparity in the quality of medical care.

2.
Hum Pathol ; 40(2): 270-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18755492

RESUMEN

Pituitary carcinomas are exceedingly rare. At present, the sole diagnostic criterion is metastatic spread, either craniospinal or systemic. There is no agreement on a histologic, immunohistochemical, and/or ultrastructural definition. We report a clinically and morphologically well-documented example of pituitary thyrotropin cell carcinoma in a man with multiple endocrine neoplasia type 1 syndrome. The tumor produced thyrotropin, alpha-subunit, and prolactin and, through electron microscopy, was found to consist solely of Thyrotroph cells. Over a protracted course, craniospinal and systemic metastases were noted. The primary and metastatic deposits of this aggressive tumor were studied. To our knowledge, this tumor is the first reported case of thyrotropin cell carcinoma occurring in association with the multiple endocrine neoplasia type 1 syndrome. The literature regarding thyrotropin carcinomas is reviewed. Based on the study of several biopsies during disease progression, we believe that the carcinoma originated de novo without an intermediary adenoma phase.


Asunto(s)
Carcinoma/secundario , Neoplasia Endocrina Múltiple Tipo 1/patología , Neoplasias Hipofisarias/patología , Tirotropina/biosíntesis , Adulto , Carcinoma/metabolismo , Neoplasias del Sistema Nervioso Central/secundario , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Neoplasia Endocrina Múltiple Tipo 1/metabolismo , Neoplasias Hipofisarias/metabolismo , Prolactina/biosíntesis
3.
J Gastroenterol ; 42(6): 497-500, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17671766

RESUMEN

BACKGROUND: We conducted a nationwide survey to estimate the incidence of neuroendocrine gastrointestinal tumors (NETs) newly diagnosed in Japan from 2002 through 2004. METHODS: Data on 1541 patients, 514 pancreatic endocrine tumors (PETs) and 1027 gastrointestinal carcinoids (GICs), were collected and analyzed. RESULTS: Nonfunctioning tumors (NF-PET) constituted 47.7% of PETs. Next in frequency were insulinoma (31.7%) and gastrinoma (8.6%). Malignancy was frequent in NF-PETs (46.1%) and gastrinomas (45.5%), but only 7.4% of insulinomas were malignant. The incidence of multiple endocrine neoplasia type-1 associated with PETs was 7.4%. The incidence of GICs was 28.8%, 5.2%, and 66.0% in foregut, midgut, and hindgut, respectively. Carcinoid syndrome and metastases were observed in only 1.7% and 5.6% of GICs, respectively. CONCLUSIONS: The incidence of NETs in Japan was clarified by this preliminary study. Comparatively large differences in GICs between Japan and Western nations were present with regard to the location, symptomatic status, and prevalence of malignancy.


Asunto(s)
Neoplasias Gastrointestinales/epidemiología , Tumores Neuroendocrinos/epidemiología , Humanos , Incidencia , Japón
4.
Mol Cell Biol ; 27(13): 4807-14, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17470551

RESUMEN

Androgen receptor (AR) mediates diverse androgen actions, particularly reproductive processes in males and females. AR-mediated androgen signaling is considered to also control metabolic processes; however, the molecular basis remains elusive. In the present study, we explored the molecular mechanism of late-onset obesity in male AR null mutant (ARKO) mice. We determined that the obesity was caused by a hypercorticoid state. The negative feedback system regulating glucocorticoid production was impaired in ARKO mice. Male and female ARKO mice exhibited hypertrophic adrenal glands and glucocorticoid overproduction, presumably due to high levels of adrenal corticotropic hormone. The pituitary glands of the ARKO males had increased expression of proopiomelanocortin and decreased expression of the glucocorticoid receptor (GR). There were no overt structural abnormalities and no alteration in the distribution of cell types in the pituitaries of male ARKO mice. Additionally, there was normal production of the other hormones within the glucocorticoid feedback system in both the pituitary and hypothalamus. In a cell line derived from pituitary glands, GR expression was under the positive control of the activated AR. Thus, this study suggests that the activated AR supports the negative feedback regulation of glucocorticoid production via up-regulation of GR expression in the pituitary gland.


Asunto(s)
Glucocorticoides/biosíntesis , Hipófisis/metabolismo , Receptores Androgénicos/metabolismo , Glándulas Suprarrenales/patología , Hormona Adrenocorticotrópica/sangre , Animales , Apoptosis , Línea Celular , Proliferación Celular , Corticosterona/sangre , Dihidrotestosterona , Retroalimentación Fisiológica , Femenino , Regulación de la Expresión Génica , Hipertrofia , Sistema Hipotálamo-Hipofisario , Hipotálamo/metabolismo , Masculino , Ratones , Ratones Noqueados , Hipófisis/patología , Sistema Hipófiso-Suprarrenal , Receptores Androgénicos/deficiencia , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo
5.
J Obstet Gynaecol Res ; 32(4): 387-95, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16882264

RESUMEN

AIM: To review five ovarian carcinomas with varying degrees of neuroendocrine differentiation (ND) using an immunohistochemical study focused on the relationship with morphological features. METHODS: ND was immunohistochemically analyzed using 21 antibodies by an indirect immunoperoxidase method, and ploidy pattern was analyzed using paraffin sections. RESULTS: The tumors were divided according to tumor cell size into 'small-sized' for case 1, 'intermediate-sized' for cases 2 and 3, and 'large-sized' for cases 4 and 5. Expressions of neuroendocrine markers and argyrophil reaction tended to be strengthened as tumor cell size increased. Cases 1, 2 and 3 showed diploid pattern and cases 4 and 5 showed aneuploid pattern. CONCLUSION: ND of ovarian carcinomas is closely related to morphological features represented by the cell size. Therefore, ovarian carcinomas with ND should be defined because the disease entity is not successfully integrated irrespective of the highly malignant potential.


Asunto(s)
Carcinoma Neuroendocrino/patología , Neoplasias Ováricas/patología , Adulto , Carcinoma Neuroendocrino/genética , Diferenciación Celular/fisiología , ADN de Neoplasias/genética , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Neoplasias Ováricas/genética , Ploidias
6.
Cells Tissues Organs ; 180(4): 237-44, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16330879

RESUMEN

Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva.


Asunto(s)
Cromograninas/genética , Cromograninas/metabolismo , Perfilación de la Expresión Génica , Glándula Submandibular/metabolismo , Glándulas Suprarrenales/metabolismo , Western Blotting , Cromogranina A , Cromograninas/análisis , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunohistoquímica , Microscopía Inmunoelectrónica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Conductos Salivales/citología , Conductos Salivales/ultraestructura , Vesículas Secretoras/ultraestructura , Glándula Submandibular/citología , Glándula Submandibular/ultraestructura
7.
Acta Neuropathol ; 108(2): 147-53, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15185102

RESUMEN

Thyrotropin (TSH)-secreting adenomas are rare and, as most adenomas are large, invasive and difficult to cure by surgery only, many require additional medical treatment. Many TSH-secreting adenomas cosecrete growth hormone (GH) and/or prolactin (PRL). We evaluated the relationship between pathology and the effect of dopamine agonist bromocriptine and somatostatin analogue octreotide in 20 operated patients with TSH-secreting adenomas. The four men and 16 women ranged in age from 23 to 62 years; three had clinically overt acromegaly; two manifested galactorrhea-amenorrhea. Endocrinologically, elevated serum GH, and/or IGF-1 were observed in six patients and elevated serum PRL was observed in eight. Immunohistochemically, 16 of the 20 adenomas were positive for GH and/or PRL (GH-positive, n=13; PRL-positive, n=9). Pituitary-specific transcription factor Pit-1 was demonstrated in the nuclei of all adenoma cells. Octreotide tests showed suppression of serum TSH (<50%) in ten of 14 patients. Preoperative octreotide treatment effectively reduced serum TSH and tumor size in two patients. Electron micrographs of octreotide-treated TSH-secreting adenomas showed shrinkage of the cytoplasm and diffuse distribution of secretory granules. Our study suggests that cosecretion of GH and/or PRL from TSH-secreting adenoma has no correlation with response of tumor cells to medical treatment.


Asunto(s)
Adenoma/patología , Antineoplásicos Hormonales/uso terapéutico , Neoplasias Hipofisarias/patología , Tirotropina/metabolismo , Adenoma/tratamiento farmacológico , Adenoma/metabolismo , Adenoma/ultraestructura , Adulto , Bromocriptina/uso terapéutico , Femenino , Hormona del Crecimiento/sangre , Antagonistas de Hormonas/uso terapéutico , Humanos , Inmunohistoquímica/métodos , Masculino , Microscopía Electrónica/métodos , Persona de Mediana Edad , Octreótido/uso terapéutico , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/ultraestructura , Prolactina/sangre , Estudios Retrospectivos , Coloración y Etiquetado
8.
Endocr J ; 49(1): 41-7, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12008749

RESUMEN

We describe a rare case of macroprolactinoma with subclinically synchronous growth hormone (GH) production. A 59-year-old man with a giant adenoma in his pituitary had elevated serum prolactin (PRL) and insulin-like growth factor (IGF)-I levels, despite normal levels of basal GH. Serum GH levels were paradoxically increased in response to an intravenous administration of thyrotropin-releasing hormone (TRH). Prolonged exposure to glucose as a result of oral glucose tolerance testing (oGTT) failed to decrease GH levels. Two-week treatment with cabergoline, a dopamine D2 receptor agonist, decreased serum PRL and GH levels, and size of the tumor. Immunohistochemistry and in situ hybridization revealed PRL-producing cells capable of synchronous GH production. Acidophilic stem cell adenoma may be responsible for these phenomena. The nature of high proliferation and invasive tumor growth should be kept in mind when managing patients with this cell type of adenoma. IGF-I levels should be followed in PRLoma, even when basal GH levels are within the normal range, because mixed PRL- and GH-producing tumors would lie underneath. Further endocrinological examinations such as TRH test and oGTT are recommended when elevated IGF-I levels are detected.


Asunto(s)
Hormona de Crecimiento Humana/biosíntesis , Prolactinoma/metabolismo , Hormona Adrenocorticotrópica/biosíntesis , Dexametasona/administración & dosificación , Glucocorticoides/administración & dosificación , Hormona de Crecimiento Humana/sangre , Hormona de Crecimiento Humana/genética , Humanos , Hidrocortisona/biosíntesis , Inmunohistoquímica , Hibridación in Situ , Factor I del Crecimiento Similar a la Insulina/análisis , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Persona de Mediana Edad , Prolactina/sangre , Prolactina/genética , Prolactina/metabolismo , Prolactinoma/patología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA