Biomedical subjects

Nan-Hsiung Feng

Publications and source records attributed to Nan-Hsiung Feng.

7 recordsLinked to original sources

PubMed2006

Primary intra-abdominal synovial sarcoma.

We report a case of primary intra-abdominal synovial sarcoma of the omentum in a 66-year-old man hospitalized for intermittent abdominal fullness for 1-2 months and tenesmus for 2 weeks. The patient had a palpable mass that was solid, hard and with well-defined thickness within his abdomen. A huge heterogeneous mass lesion over the middle abdomen that started from S2, S3 of the liver to the transverse colon was shown on abdominal computed tomography. The major cell types of the tissue mass were confirmed to be spindle and epithelial cells, which was consistent with biphasic synovial sarcoma according to pathologic and immunohistochemical findings.

Aged↗

PubMed2005

Differential expression of a V-type ATPase C subunit gene, Atp6v1c2, during culture of rat lung type II pneumocytes.

The lung alveolar epithelium consists of type I and type II pneumocytes. In vivo, the type II cell is the progenitor cell from which the type I cell originates. When freshly-isolated type II cells are cultured under conventional conditions they rapidly lose their phenotypic properties and attain characteristics of type I cells. Taking advantage of this transdifferentiation, we sought to identify genes that are differentially expressed during culture of rat type II cells. Using suppression subtractive hybridization (SSH), a vacuolar-type H+-ATPase (V-ATPase) C2 subunit gene (Atp6v1c2) was found to be enriched in freshly isolated rat type II cells compared to those cultured for 4 days. Northern blotting and reverse-transcription polymerase chain reaction (RT-PCR) confirmed the differential expression of Atp6v1c2 during in vitro culture of isolated type II cells. Expression ofAtp6v1c2 was significantly reduced early during in vitro culture: almost 90% reduction was observed after 24 h of incubation as determined by real-time PCR. In situ hybridization showed that Atp6v1c2 is expressed in both bronchiolar and alveolar lung epithelial cells, an expression pattern similar to that of surfactant protein B (SP-B). Multi-tissue Northern blotting revealed a unique tissue distribution with Atp6v1c2 expression limited to lung, kidney and testis. The presence and expression of Atp6v1c2 gene transcript isoforms, resulting from alternative splicing, were also investigated. Elucidation of differential expression of Atp6v1c2 in type II cells and further studies of its regulation may provide information useful in understanding the molecular mechanism underlying phenotypic and functional changes during transdifferentiation of alveolar epithelial cells.

Alternative Splicing↗

PubMed2005

Spontaneous pneumothorax after steroid treatment in a patient with bronchiolitis obliterans organizing pneumonia.

Bronchiolitis obliterans organizing pneumonia (BOOP) is an uncommon pulmonary disorder which is a clinicopathologic syndrome. The typical symptoms include cough, fever and dyspnea. Corticosteroid therapy is effective. Death from progressive disease is infrequent. We report a case of BOOP in a 41-year-old male non-smoker, proved by pathologic findings. After steroid therapy (prednisolone 30 mg daily) for 10 days, he developed spontaneous pneumothorax of bilateral lung fields. Responses to steroid and chest tube thoracostomy were excellent. BOOP may be complicated with spontaneous pneumothorax which may adversely affect prognosis. BOOP should be included in the differential diagnosis of patients presenting with secondary spontaneous pneumothorax.

Adult↗

PubMed2004

Effects of various antioxidants on endotoxin-induced lung injury and gene expression: mRNA expressions of MnSOD, interleukin-1beta and iNOS.

Antioxidants have been shown to be effective in attenuating acute lung injury. In this study, we determine the effects of various antioxidants by different mechanisms on the lipopolysaccharide (LPS)-induced changes. LPS was administered intravenously at a dose of 10 mg/kg to anesthetized rats. LPS induced a significant decrease in blood pressure (P < 0.01) and increased exhaled nitric oxide (NO) from 3.60+/-0.18 to 35.53+/-3.23 ppb (P < 0.01) during an observation period of 4 h. Plasma nitrate concentrations also increased from 0.61+/-0.06 to 1.54+/-0.22 micromol/l (P < 0.05). LPS-induced oxygen radical release from white blood cells isolated from rat peripheral blood also increased significantly (P < 0.001). After the experiment, the lung weight was obtained and lung tissues were taken for the determination of mRNA expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta) and manganese superoxide dismutase (MnSOD). Histological examination of the lungs was also performed. In the control group injected with saline solution, mRNA expressions of iNOS, IL-1beta, TNF-alpha and MnSOD were absent. Four hours after LPS administration, mRNA expressions of iNOS, IL-1beta, and MnSOD were significantly enhanced, but TNF-alpha was not discernibly expressed. LPS also caused a twofold increase in lung weight. Pathological examination revealed endothelial cell damage and interstitial edema. Various antioxidants were given 1 h after LPS administration. These agents include SOD, catalase (CAT), SOD + CAT or vitamin C (ascorbic acid). These antioxidants effectively reversed the systemic hypotension, reduced the quantity of exhaled NO and plasma nitrate concentration, and prevented acute lung injury. Administration of various antioxidants also significantly attenuated LPS-induced oxygen radical release by rat white blood cells. LPS induced mRNA expressions of MnSOD and iNOS were significantly depressed by these antioxidants. However, only SOD + CAT and vitamin C inhibited the mRNA expression of IL-1beta. These results suggest that oxygen radicals are responsible for LPS-induced lung injury. Antioxidants can attenuate the lung injury by inhibiting mRNA expressions of iNOS and IL-1beta.

Animals↗

PubMed2004

Pharmacological modulation of TNF production in macrophages.

The quantity and duration of production of tumor necrosis factor (TNF) is tightly controlled due to its potential to cause serious harm. For example, TNF release in response to overwhelming bacterial infection has been implicated as the first step in potentially lethal septic shock. Prostaglandins and leukotrienes are thought to play opposing roles in regulating TNF production by monocytes and macrophages. We investigated the effects of 5 drugs on the production of TNF by cells of the murine macrophage line RAW264 after stimulation with bacterial lipopolysaccharide endotoxin (LPS). These drugs were of the following 3 classes: cyclooxygenase inhibitors indomethacin (indo) and ibuprofen (ibu); 5-lipoxygenase inhibitors VZ 65 and AA-861; and methylxanthine pentoxyfilline (PTX). While indo and ibu treatment resulted in increased TNF production, PTX, VZ 65, and AA-861 significantly inhibited TNF production, whether administered simultaneously with LPS or 30 min after LPS treatment. VZ 65 and AA-861 also inhibited prostaglandin E2 (PGE2) production, coupled with an absence of any rise in intracellular cAMP. Leukotriene B4 (LTB4) levels peaked at 15 min and approached background level at 30 min after LPS treatment. Taken together, these data suggest that VZ 65 and AA-861 may inhibit TNF production through mechanism(s) independent of LTB4 production. VZ 65, AA-861, and PTX all diminished the rate of TNF mRNA transcription, yet VZ 65 and AA-861 appeared to enhance message stability. We conclude that while PTX reduced TNF protein levels by inhibiting TNF mRNA transcription, both VZ 65 and AA-861 exerted opposing effects on TNF transcription and increased mRNA stability.

Animals↗

PubMed2004

Non-septicemic Burkholderia pseudomallei liver abscess in a young man.

Melioidosis, caused by Burkholderia pseudomallei, has been increasingly recognized in Taiwan recently. Its isolation in liver abscess is rare compared to pulmonary melioidosis. We report a case of liver abscess due to B. pseudomallei in an immunocompetent 27-year-old male soldier admitted due to fever, sore throat and mild non-productive cough for 1 week. Physical examination was unremarkable except for congestion of the pharyngeal wall, moderate enlargement of the tonsils without pus coating, and palpable tender lymphadenopathy over bilateral submental regions. Antibiotic treatment with cefazolin 1 g every 8 hours intravenously was given without response. Left flank pain, followed by right flank pain associated with epigastric tenderness developed. Sonography and computed tomography scan of the abdomen demonstrated liver abscess. Aspiration of the liver abscess was performed and abscess culture yielded B. pseudomallei. Treatment with ceftazidime 2 g every 8 hours intravenously (4 weeks' duration) followed by oral regimens of amoxicillin-clavulanate was given. The patient was free of symptoms at 8 months' follow-up. Early awareness and definite diagnosis as well as institution of proper antimicrobial agents are imperative for successful treatment of melioidosis.

Adult↗

PubMed2003

Pseudomonas aeruginosa endocarditis associated with endophthalmitis caused by arteriovenous fistula and graft infection.

Bacterial endocarditis due to Pseudomonas aeruginosa arising from arteriovenous (AV) fistula and graft infection is unusual. We report an uncommon case of a 55-year-old woman housewife with chronic glomerulonephritis who had received hemodialysis (HD) for 5 years. She was admitted due to frequent episodes of AV fistula and graft infections in the past 5 years. She was admitted to our hospital because of a fever of unknown origin. During hospitalization, cardiac sonography and transesophageal echocardiography (TEE) confirmed a vegetation over the mitral valve. Blood culture yielded Pseudomonas aeruginosa. Endophthalmitis of the right eye was diagnosed by funduscopy because of painful redness of the right eye with exudative discharge. The patient was treated with ceftazidime for 9 weeks. Since then, she has been well, without any sequale after 1 year of following up. Physicians should be aware of the possibility of infective endocarditis in an uremic patient who suffers from fever of unknown origin. Early diagnosis with an adequate tool such as TEE and appropriate treatment will lead to an excellent prognosis.

Arteriovenous Shunt, Surgical↗