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An-Hang Yang

Publications and source records attributed to An-Hang Yang.

29 records · Page 2Linked to original sources
PubMed2003

Epstein-Barr virus-associated lymphoepithelioma-like carcinoma of the esophagus.

Epstein-Barr virus (EBV)-associated lymphoepithelioma-like carcinoma (LELC) rarely occurs in the esophagus. We report a case of such tumor arising in the esophagus of a 64-year-old Taiwanese woman. No tumors were detected outside the esophagus including nasopharynx by thorough clinical studies. She underwent subtotal esophagectomy. Light microscopy disclosed a poorly differentiated carcinoma morphologically reminiscent of nasopharyngeal undifferentiated carcinoma (lymphoepithelioma). Immunohistochemical stain for latent membrane protein-1 showed positivity on the tumor cells. The infiltrating lymphocytes were chiefly composed of CD8-positive cytotoxic T cells. EBV DNA was demonstrated by both nested polymerase chain reaction (PCR) in the main tumor and metastatic lymph node, and localization in the tumor cells by in situ PCR in situ hybridization (ISH). However, the result of EBV-encoded small RNA-1 ISH was negative. Our case suggests that LELC of the esophagus may be associated with EBV in the endemic area. Due to its distinct histological features, the association with EBV, and possible prognostic implication, LELC of the esophagus should be precisely diagnosed and discerned from the usual poorly differentiated carcinoma.

Carcinoma, Squamous Cell↗
PubMed2003

TNF-alpha renders human peritoneal mesothelial cells sensitive to anti-Fas antibody-induced apoptosis.

BACKGROUND: Fas-mediated apoptosis is important in the regulation of immune response. Human peritoneal mesothelial cells (HPMCs) are able to regulate peritoneal inflammation, but the role of Fas in HPMCs is not clear. This study addresses the mechanisms of Fas-mediated apoptosis in HPMCs. METHODS: Tumour necrosis factor-alpha (TNF-alpha) primed HPMCs were stimulated with agonistic anti-Fas antibody. The expression of Fas was evaluated by real-time reverse transcription polymerase chain reaction (TaqMan quantitative polymerase chain reaction) and flow cytometry. Apoptosis was assessed by nuclear morphology, TUNEL assay, fractional DNA content and cytokeratin 18 cleavage. Caspase activation and bcl-2 expression were analysed by western blotting. The phagocytosis of apoptotic HPMCs was demonstrated by immunofluorescence and transmission electron microscopy. RESULTS: Cultured HPMCs constitutively expressed Fas, and the Fas expression was upregulated by TNF-alpha. TNF-alpha primed HPMCs underwent apoptosis after anti-Fas antibody treatment, and the apoptotic HPMCs could be phagocytosed by macrophages. TNF-alpha was able to downregulate bcl-2 expression. Activation of caspase-3 and caspase-8 was noted during the apoptotic process. The inhibitors of either caspase-3 or caspase-8 could prevent the Fas-induced apoptosis in HPMCs. We also detected increased HPMC apoptosis in dialysate effluent during the recovery phase of peritonitis in peritoneal dialysis patients. CONCLUSIONS: TNF-alpha directs HPMCs to commit apoptosis via the Fas/Fas ligand pathway through a modulation of Fas and bcl-2. Our study shows that HPMCs undergo apoptosis during peritonitis and suggests that the apoptosis of HPMCs may be related to the resolution of peritoneal inflammation.

Apoptosis↗
PubMed2003

Clear cell myomelanocytic tumor of the urinary bladder.

Clear cell myomelanocytic tumors are a recently described neoplastic growth considered to be a member of the family of perivascular epithelioid cell tumor. These tumors have a predilection for falciform ligament/ligamentum teres. We report an additional case arising from the muscularis propria of the urinary bladder in a 33-year-old woman. The tumor consisted of clear to eosinophilic, epithelioid, and spindled cells arranged in fascicles or packets. A delicate vascular stroma was found among the nests. Immunohistochemically, the tumor cells were typically positive for HMB-45 and smooth muscle actin but negative for S-100 protein, Melan-A, desmin, and pan-cytokeratin. The patient has been free of the disease since the excision of the tumor 6 years ago. This case, in association with the expanding list of perivascular epithelioid cell tumor reported in different sites, suggests that this type of neoplasm may be ubiquitous.

Adenocarcinoma, Clear Cell↗
PubMed2003

Malignant perivascular epithelioid cell tumor involving the prostate.

Perivascular epithelioid cell tumor (PEComa) is a neoplasm chiefly composed of HMB-45-positive epithelioid cells with clear-to-granular cytoplasm and a perivascular distribution. We describe such a tumor involving the prostate and seminal vesicle in a 46-year-old man. The tumor had characteristic histologic features of PEComa. Immunohistochemically, the tumor cells were positive for HMB-45 but negative for epithelial markers, Melan-A, and S100 protein. The tumor behaved in a malignant fashion, and the patient died of the disease 4 years after diagnosis.

Antigens, Neoplasm↗
PubMed2003

Renal tubular dysgenesis in siblings.

Renal tubular dysgenesis is a recently recognized autosomal recessive condition characterized by absence or poor development of proximal convoluted tubules, clinical presentation of oligohydromnios, Potter sequence, and neonatal respiratory failure. Only a few cases of renal tubular dysgenesis have been diagnosed. We report 2 cases from a single family. Histologically, the renal cortices showed crowding of the glomeruli and primitive tubules, most of which demonstrated positive cytoplasmic staining for epithelial membrane antigen and peanut lectin. Electron microscopy of the kidneys of the second baby revealed absence of differentiated characteristics of the proximal tubules.

Female↗
PubMed2002

Detection of Epstein-Barr virus genome within thymic epithelial tumours in Taiwanese patients by nested PCR, PCR in situ hybridization, and RNA in situ hybridization.

Epstein-Barr virus (EBV) is known to be associated with a variety of tumours, including Burkitt's lymphoma, nasopharyngeal carcinoma, and some carcinomas of other organs with similar lymphoepithelioma-like features. The association between EBV and thymic epithelial tumours is inconclusive, as reports in this regard are not entirely consistent and the methods employed are of different sensitivity and specificity. This study examined 78 thymomas and 21 thymic carcinomas in Taiwanese patients, to detect the viral genome at both DNA and RNA levels. The tissue blocks were first screened by nested polymerase chain reaction (PCR) targeting on the first tandem internal repeats. The positive cases were further submitted for viral localization by in situ PCR insitu hybridization (ISH) and Epstein-Barr-encoded RNA-1 (EBER-1) ISH. None of the thymomas showed a detectable EBV genome. Eight thymic carcinomas were positive for EBV by nested PCR, of which six displayed nuclear signals within the tumour cells by in situ PCR ISH and/or RNA ISH, one displayed signals within the lymphocytes, and one showed no discernible in situ signals. Most of them exhibited a lymphoepithelioma-like morphology. These results show that nested PCR is a sensitive method for screening the EBV genome in thymic epithelial tumours. In situ PCR ISH is reliable for localization of the virus, in addition to EBER-1 RNA ISH. Thymomas are not related to EBV, even in this endemic area. Thymic carcinomas, especially the lymphoepithelioma-like thymic carcinomas, are more often associated with the virus.

Adult↗
PubMed2002

Eosinophilic heart disease with vasculitis: supported by HeartMate left ventricular assist device and heart transplantation.

Eosinophilic heart disease is rarely seen in clinical practice. We report a patient with eosinophilic heart disease who presented with acute myocardial infarction and congestive heart failure. Because of lack of a donor organ and progressive deterioration of his general condition in spite of intraaortic balloon pumping, a left ventricular assist device (HeartMate 1000 IP; Thermo Cardiosystems Inc, Woburn, MA) was implanted before development of irreversible multiple organ failure and was followed by heart transplantation.

Adult↗
PubMed2002

The association of non-small-cell lung cancer, focal segmental glomerulosclerosis, and platelet dysfunction.

Neoplasm-related nephrotic syndrome exhibiting focal segmental glomerulosclerosis (FSGS) has been reported mainly in patients with hematologic malignancies. The association of FSGS with carcinoma is very rare and nephrotic syndrome caused by FSGS has not yet been reported in patients with lung cancer. We report a case of nephrotic syndrome caused by FSGS in a 61-year-old man with advanced non-small-cell lung cancer. In addition, platelet dysfunction evidenced by prolonged bleeding time was noted. The renal problem and prolonged bleeding time resolved dramatically during radiotherapy for lung cancer. We speculate that both FSGS and prolonged bleeding time are paraneoplastic syndromes associated with lung cancer, although the underlying mechanisms of both conditions remain to be elucidated.

Bleeding Time↗
PubMed2002

Thyrotropin-secreting pituitary adenoma with growth hormone hypersecretion.

A 34-year-old woman suffered from palpitation, easy sweating, heat intolerance, increased appetite, irregular menstrual cycle and hand tremor for 1 year. Thyroid function tests showed elevated serum thyroxine (T4), tri-iodothyronine (T3) and thyrotropin (TSH). Computerized tomography (CT) revealed pituitary tumor with supraseller extension. Thyrotropin releasing hormone (TRH) test showed blunted TSH response with elevated baseline level and paradoxical growth hormone (GH) response with elevated baseline level. T3 suppression test (T3 60 microg per day x 10 days) showed no inhibition of TSH (11.1 microU/mL, normal range < 6.2 microU/mL). She received transphenoidal approach and removal of tumor which measured 0.5 x 0.3 x 0.2 cm. Histopathologically, it was a pituitary adenoma which was immunoreactive for TSH, GH, follicular stimulating hormone (FSH) and luteinizing hormone (LH). To our knowledge, this case is the first case of TSH-secreting pituitary adenoma in Taiwan.

Adenoma↗
PubMedDate not supplied

High prevalence of SV40 infection in patients with nodal non-Hodgkin's lymphoma but not acute leukemia independent of contaminated polio vaccines in Taiwan.

Recent studies have linked simian virus 40 (SV40) to non-Hodgkin's lymphoma (NHL), especially in countries in which people were exposed to contaminated polio vaccines prior to 1963. In Taiwan, nearly all children were not exposed to contaminated polio vaccine during this period; the relationship between SV40 infection and hematological malignancies is unclear and deserves to be studied. Using PCR amplification of SV40 large T antigen DNA, confirmed by Southern blot hybridization and sequence analysis, 91 frozen lymph nodes from NHL patients were examined. Thirteen (14.3 percent) showed positive for SV40. All other test samples, including diagnostic bone marrow from patients with acute leukemia, peripheral blood from 10 relatives of SV40 positive-patients and 91 age-matched normal volunteers, and 5 reactive hyperplastic lymphoid tissues, showed negative. These results may reflect that human-to-human transmission of SV40 is independent of contaminated polio vaccines; and SV40 is possibly associated with the development of NHL in Taiwan (p = 0.0001). Prospective studies are needed to determine the prevalence of SV40 infections in our and other human populations and to explore the means of transmission of the virus.

Acute Disease↗