Biomedical subjects

C-W Yang

Publications and source records attributed to C-W Yang.

5 recordsLinked to original sources

PubMed2006

Free microvascular transfer of the vermiform appendix for creation of a tracheo-oesophageal fistula: A new method of voice reconstruction.

BACKGROUND: Voice rehabilitation following laryngectomy can take many forms. As its basic premise, vibrating air must be transferred to the mouth where articulation takes place and speech can be produced. It requires a source of air, a conduit for transfer, and a mechanism for prevention of regurgitation and aspiration. Creating a tracheo-oesophageal fistula and maintaining it with a vascularised appendix has been the intention of this report. METHODS: Three patients with an average age of 53 years underwent the procedure of free transfer of the appendix for voice restoration during the months of September 2004 through December 2004. All patients had laryngectomies and one had total cervical oesophageal reconstruction with a pedicled pectoralis major flap. Voice evaluation, swallowing function, and presence of aspiration were evaluated. RESULTS: All flaps survived without complications. The results of swallowing function were unaltered from preoperative levels. All flaps remained patent at an average follow-up period of 8 months. All three patients could produce loud voice, which was intelligible at a reasonable distance. Maximal phonation time was 4s in two patients and 5s in one patient. Voice rehabilitation using the free appendix flap can achieve a phonation time which is low and words and short phrases that are intelligible but limited so far to this level. The donor site morbidity is low and aspiration was not present. The results of this study indicate that this method may have a potential role in voice reconstruction but requires more experience and refinement of this technique.

Anastomosis, Surgical↗

PubMed2006

Toll-like receptor 2 mediates early inflammation by leptospiral outer membrane proteins in proximal tubule cells.

Tubulointerstitial nephritis is a cardinal renal manifestation in leptospirosis and LipL32, the major lipoprotein component of leptospiral outer membrane proteins (OMPs), induces a robust inflammatory response in cultured renal proximal tubule cells through a nuclear factor-kappaB-related pathway. Here, we investigated whether Toll-like receptor (TLR), known to play a pivotal role in innate immunity, could mediate the inflammatory response induced by leptospiral OMPs in renal proximal tubule cells. TLR expression was analyzed by flow cytometry and indirect immunofluorescence in cultured mouse proximal tubule (pyruvate kinase simian virus 40-proximal straight (PKSV-PR)) cells. Reverse transcription-competitive polymerase chain reaction and enzyme-linked immunosorbent assay were undertaken to analyze the inducible effects of inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1 also termed CCL2) by pathogenic and non-pathogenic leptospiral OMPs and recombinant lipoproteins in either PKSV-PR cells or TLR-transfected human embryonic kidney (HEK) 293 cells. Anti-TLR antibodies were used for blocking experiments. Leptospira santarosai serovar Shermani OMPs and LipL32 induced a significant increase in TLR2 but not TLR4 expression in PKSV-PR cells. The increase in iNOS and CCL2/MCP-1 mRNA expressions could be prevented by an anti-TLR2 antibody, but not by an anti-TLR4 antibody. Furthermore, leptospiral OMPs stimulated both CCL2/MCP-1 mRNA and secreted protein in transfected HEK 293 cells with a TLR2-expressing plasmid, but had no effect in cells with a TLR4-expressing plasmid. In conclusion, these findings indicate that the stimulation of iNOS and CCL2/MCP-1 caused by pathogenic leptospiral OMPs, in particular LipL32, in proximal tubule cells requires TLR2 for the early inflammatory response.

Animals↗

PubMed2006

Upregulation of chemokine CXCL1/KC by leptospiral membrane lipoprotein preparation in renal tubule epithelial cells.

We have previously shown that leptospiral membrane lipoprotein preparation (LMLP) extracted from pathogenic Leptospira santarosai serovar Shermani stimulates the secretion of pro-inflammatory mediators in renal tubule epithelial cells, and implicated its role in the initiation of tubulointerstitial nephritis. Renal tubulointerstitial injury is characterized by inflammatory cell infiltrate; however, the stimuli for leukocyte recruitment are not fully understood. Initial studies by cytokine protein array analysis revealed significant upregulation of neutrophil-chemoattractant keratinocyte-derived chemokine (CXCL1/KC) at nanogram range of LMLP stimulation in cultured murine proximal tubule cells (PTCs). As PTCs express Toll-like receptors (TLRs), this study investigated the roles of TLR signaling pathways in PTCs stimulated by LMLP and its relation to CXCL1/KC secretion. The LMLP stimulated the early secretion of CXCL1/KC and enhanced the level of TLR2 mRNA expression in PTCs through time- and dose-dependent effect. The LMLP-stimulated secretion of human growth-related oncogene alpha, a functional homolog to murine KC, in TLR-defective human embryonic kidney 293 cells transiently transfected with TLR2-expressing plasmids and the response was augmented by coexpression of TLR1 and TLR2. Moreover, silencing of TLR2, myeloid differentiation factor 88, and TNF receptor-associated factor 6 with specific small interfering RNA significantly reduces the response caused by LMLP in PTCs. The LMLP-stimulated CXCL1/KC secretion was also significantly reduced by pre-incubating PTCs with a specific p38 inhibitor. These results indicate that LMLP stimulates the production of CXCL1/KC to recruit polymorphonuclear neutrophils at the site of inflammation through a TLR2-mediated pathway in renal tubule cells.

Animals↗

PubMed2006

Prospective cohort study comparing sequential organ failure assessment and acute physiology, age, chronic health evaluation III scoring systems for hospital mortality prediction in critically ill cirrhotic patients.

The aim of the study was to evaluate the usefulness of sequential organ failure assessment (SOFA) and acute physiology, age, chronic health evaluation III (APACHE III) scoring systems obtained on the first day of intensive care unit (ICU) admission in predicting hospital mortality in critically ill cirrhotic patients. The study enrolled 102 cirrhotic patients consecutively admitted to ICU during a 1-year period. Twenty-five demographic, clinical and laboratory variables were analysed as predicators of survival. Information considered necessary to calculate the Child-Pugh, SOFA and APACHE III scores on the first day of ICU admission was also gathered. Overall hospital mortality was 68.6%. Multiple logistic regression analysis revealed that mean arterial pressure, SOFA and APACHE III scores were significantly related to prognosis. Goodness-of-fit was good for the SOFA and APACHE III models. Both predictive models displayed a similar degree of the best Youden index (0.68) and overall correctness (84%) of prediction. The SOFA and APACHE III models displayed good areas under the receiver-operating characteristic curve (0.917 +/- 0.028 and 0.912 +/- 0.029, respectively). Finally, a strong and significant positive correlation exists between SOFA and APACHE III scores for individual patients (r(2) = 0.628, p < 0.001). This investigation confirms the grave prognosis for cirrhotic patients admitted to ICU. Both SOFA and APACHE III scores are excellent tools to predict the hospital mortality in critically ill cirrhotic patients. The overall predictive accuracy of SOFA and APACHE III is superior to that of Child-Pugh system. The role of these scoring systems in describing the dynamic aspects of clinical courses and allocating ICU resources needs to be clarified.

APACHE↗

PubMed2005

Should bleeding tendency deter abdominal paracentesis?

BACKGROUND AND AIMS: This study was conducted to evaluate the complications and bleeding associated with either thrombocytopoenia or prolongation of prothrombin time for ultrasound-guided abdominal paracentesis in the emergency department. STUDY DESIGN AND PATIENTS: In an emergency department of a tertiary centre, patients receiving ultrasound-guided abdominal paracentesis by the emergency physicians were prospectively enrolled. Patient characteristics, the preprocedure international normalised ratio for prothrombin time and the platelet count, and the procedure-related complications were collected and analysed. RESULTS: For a 2-year study period, a total of 410 abdominal paracenteses in 163 patients were investigated. The preprocedure international normalised ratio for prothrombin time was more than 1.5 in 142 paracenteses; the preprocedure platelet count was less than 50 x 10(3) microL(-1) in 55 paracenteses. Only two out of 410 procedures (0.5%, 95% confidence interval=0.1-1.8%) were associated with minor complications of cutaneous bleeding in the same patient (0.6%, 95% confidence interval=0.1-3.4%) at different visits. There was no significant procedure-related bleeding or complications even in patients with marked thrombocytopoenia or prolongation in international normalised ratio. CONCLUSIONS: Bleeding complication of ultrasound-guided abdominal paracentesis is uncommon and appears to be very mild, regardless of preprocedure international normalised ratio or platelet count. Routine correction of prolonged international normalised ratio or thrombocytopoenia before abdominal paracentesis may not be necessary.

Abdominal Cavity↗