Science, technology, engineering, and mathematics (STEM) as a vehicle for supporting service learning

2016-2017 > Academic research: refereed > Refereed conference paper201804_a bcmaVersion of RecordPublishe

Another light in the dark: review of new method for the arthroscopic repair of triangular fibrocartilage complex

The triangular fibrocartilage complex (TFCC) is an anatomically and biomechanically important structure. Repair of radial-sided TFCC tear has previously been challenging. We designed a new method of radial-sided TFCC tear repair and found that it was also applicable for ulnar-sided TFCC tear repair. From October 2006 to December 2010, 10 patients underwent this operation and were reviewed: 9 men and 1 woman, with a mean age of 33.9 years. Average postoperative follow-up was 8 months. We graded results according to the Mayo modified wrist score. We rated 2 of the 10 patients (20%) as 'excellent,' 3 (30%) as 'good,' and 5 (50%) as 'fair.' The 5 patients who were rated as 'fair' returned to regular jobs or had restricted employment. Based on this small sample, we recommend that this technique be considered an alternative method for TFCC repair.postprin

Tumor cyclooxygenase-2 levels correlate with tumor invasiveness in human hepatocellular carcinoma

Aim: Recent studies suggested that cyclooxygenase-2 (COX-2) enhances tumor angiogenesis via upregulation of vascular endothelial growth factor (VEGF). Although COX-2 expression has been demonstrated in hepatocellular carcinoma (HCC), the significance of COX-2 in progression of HCC remains unclear. This study evaluated the clinicopathological correlation of COX-2 level and its relationship with VEGF level in HCC. Methods: Fresh tumor tissues were obtained from 100 patients who underwent resection of HCC. COX-2 protein expression was examined by immunohistochemistry, and quantitatively by an enzyme immunometric assay (EIA) of tumor cytosolic COX-2 levels. Tumor cytosolic VEGF levels were measured by an ELISA. Results: Immunostaining showed expression of COX-2 in tumor cells. Tumor cytosolic COX-2 levels correlated with VEGF levels (r = 0.469, P<0.001). Correlation with clinicopathological features showed significantly higher tumor cytosolic COX-2 levels in the presence of multiple tumors (P = 0.027), venous invasion (P = 0.030), microsatellite lesions (P = 0.037) and advanced tumor stage (P = 0.008). Higher tumor cytosolic COX-2 levels were associated with worse patient survival. Conclusion: This study shows that elevated tumor COX-2 levels correlate with elevated VEGF levels and invasiveness in HCC, suggesting that COX-2 plays a significant role in the progression of HCC. © 2005 The WJG Press and Elsevier Inc. All rights reserved.published_or_final_versio

CRTC1 transcriptional coactivator is required for hepatitis B virus gene expression and replication

This journal suppl. entitled: Metabolism, Diet and Disease 2014: Cancer and metabolismConference Theme: Cancer and metabolismPoster Presentation: P31BACKGROUND: Chronic hepatitis B virus (HBV) infection occurs in over 400 million people worldwide, 15-40% of whom will terminally develop severe liver diseases including hepatocellular carcinoma. Although development of HCC is a multi-step process, high HBV DNA level is a major risk factor for disease progression. Transcription of HBV from the cccDNA template is essential for its replication and requires CREB transcription factor, a master regulator of cell metabolism. However, transcriptional coactivators that facilitate CREB-dependent activation of HBV transcription remain to be identified and characterized …published_or_final_versio

Molecular characterization and expression analysis of a hepcidin gene from rice field eel (Monopterus albus)

Hepcidin is a cysteine-rich, dual-function peptide with antimicrobial activity that plays crucial roles in iron homeostasis. A few hepcidin-like genes have been isolated from teleost. Here, we have identified a hepcidin-like gene from rice field eel (RFE), Monopterus albus. Nucleotide sequences including cDNA and genomic DNA (GenBank accession numbers: FJ436808 and FJ594996, respectively) and deduced amino acid sequences were presented. In the 949 bp-long genomic sequence, two introns and three exons were identified. The full-length cDNA encodes a prepropeptide of 90 amino acid residues. RTPCR analysis suggested that hepcidin transcripts are highly abundant in the liver and kidney, less abundant in the heart, skin, brain, blood cells, intestine, spleen and stomach and undetectable in muscle. After challenged with Aeromonas hydrophila infection or iron-dextran stimulation, the hepcidin transcript levels were analyzed by RT-PCR. The results revealed that the expression of hepcidin dramatically increased at 24 h post-infection of the pathogen injection. Moreover, hepcidin mRNAs in the liver, intestine and brain were 2.4, 1.5 and 2-fold increase, respectively, compared with the control animals after 5 days in iron-dextran injected RFEs.Key words: Rice field eel, Monopterus albus, hepcidin, gene expressio

Ubiquitination and proteosome-dependent degradation of the activated form of human liver-enriched transcription factor CREB-H regulated by protein kinase A

Poster Presentation - Theme 1: Cell biologyCREB-H is a membrane-bound bZIP transcription factor which is mainly expressed in liver and small intestine. CREB-H plays important roles in the regulation of lipid metabolism, iron metabolism, gluconeogenesis and acute phase response. CREB-H is proteolytically activated by regulated intramembrane proteolysis to generate a C-terminal truncated form known as ...postprin

Regulation of human cardiac KCNQ1/KCNE1 channel by epidermal growth factor receptor kinase

The aim of the present study was to investigate whether/how the recombinant human cardiac I Ks could be regulated by epidermal growth factor receptor kinase in HEK 293 cells stably expressing hKCNQ1/hKCNE1 genes using the approaches of perforated patch clamp technique, immunoprecipitation and Western blot analysis. It was found that the broad spectrum isoflavone tyrosine kinase inhibitor genistein and the selective epidermal growth factor receptor kinase inhibitor tyrphostin AG556 suppressed the recombinant I Ks, and their inhibition was countered by the protein tyrosine phosphatase inhibitor orthovanadate. The Src-family kinase inhibitor PP2 reduced the current, but the effect was not antagonized by orthovanadate. Immunoprecipitation and Western blot analysis revealed that tyrosine phosphorylation level of hKCNQ1 protein was decreased by genistein or AG556, but not by PP2. These results provide the novel information that epidermal growth factor receptor kinase, but not Src-family kinases, regulates the recombinant cardiac I Ks stably expressed in HEK 293 cells via phosphorylating KCNQ1 protein of the channel. © 2009 Elsevier B.V. All rights reserved.postprin

Quantitative analysis of two isoflavones in Pueraria lobata flowers from eleven Chinese provinces using high performance liquid chromatography

<p>Abstract</p> <p>Background</p> <p><it>Pueraria lobata </it>flower (<it>Gehua</it>) is a medicinal herb to treat intoxication, hepatic and gastrointestinal tract lesion induced by alcohol. This study aims to develop a new HPLC method for the determination of two major isoflavones in <it>P. lobata </it>flowers, namely tectoridin and 6"-O-xylosyl-tectoridin.</p> <p>Methods</p> <p>A high performance liquid chromatography (HPLC) method with a C₁₈column (250 mm × 4.6 mm, 5 μm) was developed for the quantitative analysis of tectoridin and 6"-O-xylosyl-tectoridin, the main isoflavone components in <it>P. lobata </it>flower. A simple gradient of acetonitrile/water (0 min 15:85; 35 min 50:50; 36 min 15:85; 40 min 15:85; v/v) was used, and 265 nm was selected as detection wavelength. Tectoridin and 6"-O-xylosyl-tectoridin were used as the external standards in quality control of <it>P. lobata </it>flower for the first time. The method was applied to practical use in quality assessment of eleven batches of <it>P. lobata </it>flower samples in Chinese herbal medicine market.</p> <p>Results</p> <p>The peak area response was linear for tectoridin in the 11.8-236.4 μg/mL range with a correlation coefficient of 0.9996 (P < 0.001), and for 6"-O-xylosyl-tectoridin in the 10.33-185.99 μg/mL range with a correlation coefficient of 0.9984 (P < 0.001) respectively. The average recoveries were 102.7-103.7% for tectoridin and 95.7-103.2% for 6"-O-xylosyl-tectoridin (RSDs < 3%), and the intra-day and inter-day RSDs of the two components were less than 2%. This HPLC method was applied to assess the quality of <it>P. lobata </it>flower from eleven provinces in China. <it>P. lobata </it>flowers from northern China contained 26.46-43.28 mg/g of tectoridin and 30.90-48.23 mg/g of 6"-O-xylosyl-tectoridin comparing to 10.00-19.81 mg/g of tectoridin and 11.08-37.03 mg/g of 6"-O-xylosyl-tectoridin in those from southern China.</p> <p>Conclusion</p> <p>The results showed that <it>P. lobata </it>flowers from northern China contained more tectoridin and 6"-O-xylosyl-tectoridin than those from southern China.</p

Management and outcome of antenatally diagnosed congenital cystic adenomatoid malformation of the lung

Objective: To review the management and outcome of babies with antenatally diagnosed congenital cystic adenomatoid malformation. Design: Retrospective cohort review. Setting: Tertiary neonatal care unit at Queen Mary Hospital and antenatal diagnostic centre at Tsan Yuk Hospital. Patients: Consecutive patients with antenatally suspected congenital cystic adenomatoid malformation in their concepti among antenatal patients attending Tsan Yuk Hospital from 1994 to 2002. Twenty-four of 33 cases were referred to Queen Mary Hospital for postnatal management and for whom comprehensive records were available for analysis in 23. Interventions: Postnatal interventions in their babies included investigational imaging for congenital cystic adenomatoid malformation and surgery. Main outcome measures: Antenatal and postnatal outcome, as well as pathology of the excised lesions. Results: Antenatal outcome: termination of pregnancy in two cases and spontaneous abortion in one; in-utero regression was documented in nine cases and in one hydropic change was apparent. Postnatal outcome: only eight of 20 babies born alive had symptoms in neonatal period. Two developed serious infective complications in infancy, one with documented in-utero regression. Pulmonary parenchymal abnormalities were detected on computed tomography of the thorax in six of seven cases with normal or non-specific chest radiograph findings. Among nine cases with in-utero regression, congenital cystic adenomatoid malformation was confirmed by operative histology in five and abnormal computed tomography findings in three. Fifteen babies underwent surgical excision, one of whom died because of severe pre-existing pulmonary hypoplasia and nine endured minor postoperative complications. A favourable outcome was documented at a mean follow-up of 22 months (range, 2 months-7 years). Conclusions: In-utero regression of congenital cystic adenomatoid malformation on antenatal ultrasound may not represent genuine resolution. Computed tomographic thorax should be considered in all newborns with antenatally diagnosed congenital cystic adenomatoid malformation, and if confirmed early operation before first hospital discharge is recommended.published_or_final_versio

Myocardial fiber length mapping with MR diffusion tensor imaging

Diffusion tensor MRI is emerging as a rapid, nondestructive method to map myocardial fiber organization. A precise biological description of myocardial fiber performance requires knowledge of four variables: length, force, velocity and time. However, study of quantification of myocardial fiber length is lacking. The current study aims to show myocardial fiber length maps of formalin-fixed heats. Diffusion tensor MRI with medium diffusion resolution (15 directions) was performed in one isolated pig heart. Fiber length maps were investigated in multiple short-axis slices. The results provide supplementary information of myocardial fiber organization. To our knowledge, the present study is the first report of the myocardial fiber length mapping. © 2005 IEEE.published_or_final_versio