Biomedical subjects

Pan-Chyr Yang

Publications and source records attributed to Pan-Chyr Yang.

132 records · Page 8Linked to original sources

PubMed2002

Primary liver abscess caused by one clone of Klebsiella pneumoniae with two colonial morphotypes and resistotypes.

Two diabetic patients with primary liver abscess, who initially responded unsatisfactorily to intravenous ceftriaxone or cefoxitin treatment and had abscess drainage, were found to be infected with a single clone of Klebsiella pneumoniae with two different colonial morphotypes and resistotypes. Primary liver abscess caused by second-generation cephalosporin-resistant K. pneumoniae strains may be an emerging problem in Taiwan.

Adult↗

PubMed2002

Osteogenic differentiation of mesenchymal stem cells derived from bone marrow of patients with myeloproliferative disorders.

BACKGROUND: It has been frequently reported that culture-expanded mesenchymal stem cells from bone marrow of healthy donors can be induced to differentiate to osteocytic lineage. This study examined the potential for osteogenic differentiation of mesenchymal stem cells obtained from two patients with myeloproliferative disorders. METHODS: Mesenchymal stem cells were derived from bone marrow aspirates obtained in an outpatient clinic from two patients, one with polycythemia vera and the other with essential thrombocythemia. Nucleated bone marrow cells were directly cultured in flasks. Adherent fibroblastic cells in monolayers were isolated by removing nonadherent cells during medium changes. Osteogenic differentiation was induced in expanded adherent cells for 2 weeks in osteogenic medium containing 100 nmol/L dexamethasone, 10 mmol/L beta-glycerophosphate, and 0.05 mmol/L L-ascorbic acid-2-phosphate. Osteogenic differentiation was evaluated by alkaline phosphatase staining and determination of calcium in deposited minerals on culture plates. The expression of osteopontin mRNA was determined by reverse transcription-polymerase chain reaction. RESULTS: After induction in osteogenic medium, the expression of alkaline phosphatase in mesenchymal stem cells became more intense. Induced alkaline phosphatase-positive cells assumed an irregular shape with multiple spiculate projections, while uninduced alkaline phosphatase-positive cells had a flattened polygonal shape or were elongated. Calcium deposition on the plates of induced cells was 0.39 +/- 0.03 mumol/well in cells from the patient with polycythemia vera and 0.54 +/- 0.03 mumol/well in cells from the patient with essential thrombocythemia, but was not detectable in uninduced cells from either patient. Induction by osteogenic medium markedly increased the expression of osteopontin mRNA in stem cells derived from both patients. CONCLUSIONS: In this study, mesenchymal stem cells obtained from aspiration of bone marrow in patients with myeloproliferative disorders were expanded by culture. After osteogenic induction, these cells were shown to be able to differentiate into osteocytic lineage in vitro.

Cell Differentiation↗

PubMed2002

Poland's syndrome with spontaneous pneumothorax: report of two cases.

Poland's syndrome is an uncommon congenital anomaly of the chest wall characterized by the absence of the pectoralis major muscle and other nearby musculoskeletal components. Many associated aberrations over the thoracic cage, intrathoracic organs, and upper limbs have been reported. However, spontaneous pneumothorax in these patients has not been reported. Here, we describe two patients with both Poland's anomaly and spontaneous pneumothorax. One patient was a 16-year-old boy with left chest wall hypoplasia and pneumothorax on the right side. The other was a 27-year-old man with right chest wall hypoplasia, hand brachydactyly, and pneumothorax. Pneumothorax in both patients was treated with bullectomy and mechanical pleurodesis with the aid of videothoracoscopy, and the postoperative courses were smooth. Blood supply disruption has been hypothesized as a pathogenic mechanism of both spontaneous pneumothorax and Poland's syndrome, suggesting an association between these two diseases.

Adolescent↗

PubMed2002

Small-cell lung cancer presenting with Lambert-Eaton myasthenic syndrome and respiratory failure.

Lambert-Eaton myasthenic syndrome (LEMS) is a neuromuscular disorder characterized by defective neurotransmitter release at presynaptic terminals. It is caused by an IgG autoantibody reacting against voltage-gated calcium channels. Severe LEMS complicated by ventilatory failure is rare. We report a case of small-cell lung cancer (SCLC) presenting with LEMS and ventilatory failure in a 67-year-old man who initially presented with progressive limb weakness for 6 months and tachypnea with shallow breathing for 1 week. LEMS was diagnosed through electrophysiologic studies. Chest radiography and computerized tomography showed a huge mass lesion over the left anterior and middle mediastinum with an encasement of the left pulmonary artery. Cytologic examination of ultrasound-guided fine needle aspiration disclosed SCLC. Successful treatment in combination with plasma exchange and chemotherapy resulted in dramatic tumor regression and LEMS remission, which were confirmed by chest radiography and electrophysiologic studies. This case suggests that plasma exchange and chemotherapy can be effective in treating SCLC with severe LEMS that produces ventilatory failure.

Aged↗

PubMedDate not supplied

Video-assisted thoracic surgery for spontaneous pneumothorax: outcome of 189 cases.

The crucial role of video-assisted thoracic surgery (VATS) in the treatment of spontaneous pneumothorax is well acknowledged today. Experiences of such patients undergoing VATS were reported to evaluate the feasibility of such surgical approach. From January 1, 1996 to January 1, 2002, 189 patients (18.3%) underwent VATS treatment for first onset or recurrent primary pneumothorax (n = 134), secondary pneumothorax (n = 49), and re-do VATS (n = 6) pneumothorax of 1034 VATS procedures performed by one surgeon. The surgical approaches for these patients were through scope and working ports, and in six (3.2%) of them, the procedures were converted to open thoracotomy because of pleural adhesion or other causes. Bullae over apices or other sites of lung were identified in 164 (86.8%) patients. Mechanical pleurodesis with gauze abrasion or electrocoagulation was performed on all patients, and chemical pleurodesis with minocycline intrapleural injection or talc powder poudrage was performed on 144 (76.2%) of them. The bullae was excised with endo-GIA (n = 122), endo-loop (n = 23), electroablation (n = 9), and suturing through open or endoscopic port (n = 10). The operation time ranged from 23 to 355 minutes (42.4 +/- 12.6 minutes). The mean postoperative chest tube duration and hospital stay were 2.4 +/- 1.3 (range, 1-26) and 4.3 +/- 1.2 (range, 1-35) days. Complication occurred in 15 cases (7.9%), including 9 patients with persistent air-leakage (> 7 days), 3 patients with bleeding, 6 patients with pneumonia or ventilator dependence, and 3 patients with wound infection. Recurrence occurred in six (3.2%) patients. Two patients (1.1%) died of complications related to underlying disease (severe emphysema) postoperatively. VATS treatment is a good choice for the treatment of recurrent primary spontaneous pneumothorax. It can also be used for patients with first onset spontaneous or traumatic pneumothorax with persistent air leakage or secondary pneumothorax. We preferred bullectomy with endo-GIA because it was safer, and the specimen could possibly reveal the underlying disease.

Adolescent↗

PubMedDate not supplied

Distinct gene expression profiles in gastric epithelial cells induced by different clinical isolates of Helicobacter pylori--implication of bacteria and host interaction in gastric carcinogenesis.

BACKGROUND/AIMS: Helicobacter pylori (H. pylori) infection is a major risk factor of peptic ulcer, gastric cancer, and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. The interplay between H. pylori and host is an important issue for elucidation of pathogenesis of H. pylori-related diseases. We aimed to examine simultaneously dynamic changes of multiple molecular pathways of infection affected by different H. pylori strains by cDNA microarrays. METHODOLOGY: To elucidate the cross-talk between H. pylori and gastric epithelial cells, we isolated three different H. pylori strains from patients with gastric cancer (GC), duodenal ulcer (DU), and gastric MALT lymphoma (MA). The bacteria were co-cultured with gastric epithelial cells (AGS) and total RNAs were extracted from AGS cells and used for detection of genes represented in the microarray. RESULTS: Of the 12,814 clones on the microarray, there were 522 genes expressed differently in the three groups. Of the 522 genes, there were 4 genes, 4 genes and 13 genes, either up- or down-regulated more than twofold change, in AGS cells induced specifically by GC, MA, and DU strain, respectively. The GC and DU strains induced more genes involving in carcinogenesis, such as pim-1, jun B, and VEGF. CONCLUSIONS: Our data by cDNA microarray suggest bacterial factors may determine the outcomes of H. pylori infection. The expression profiles of cDNA microarray provide clues for diagnosis, treatment, and prevention of H. pylori-related gastroduodenal diseases.

Cell Line, Tumor↗