Protective Effect of Biological Osmolytes against Heat- and Chaotropic Agent-Induced Denaturation of Bacillus licheniformis γ-Glutamyl Transpeptidase

( Huei-fen Lo ),( Meng-chun Chi ),( Min-guan Lin ),( Yuan-gin Lan ),( Tzu-fan Wang ),( Long-liu Lin ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.9

In the present study, the stabilizing effect of four different biological osmolytes on Bacillus licheniformis γ-glutamyl transpeptidase (BlGGT) was investigated. BlGGT appeared to be stable under temperatures below 40°C, but the enzyme retained less than 10% of its activity at 60°C. The tested osmolytes exhibited different degrees of effectiveness against temperature inactivation of BlGGT, and sucrose was found to be the most effective among these. The use of circular dichroism spectroscopy for studying the secondary structure of BlGGT revealed that the temperature-induced conformational change of the protein molecule could be prevented by the osmolytes. Consistently, the molecular structure of the enzyme was essentially conserved by the osmolytes at elevated temperatures as monitored by fluorescence spectroscopy. Sucrose was further observed to counteract guanidine hydrochloride (GdnHCl)- and urea-induced denaturation of BlGGT. Taken together, we observed evidently that some well-known biological osmolytes, especially sucrose, make a dominant contribution to the structural stabilization of BlGTT.

The simple and easy way to manufacture counter electrode for dye-sensitized solar cells

Jo-Lin Lan,Yung-Yun Wang,Chi-Chao Wan,Tzu-Chien Wei,Hsien-Ping Feng,Chao Peng,Hai-Peng Cheng,Ya-Huei Chang,Wen-Chi Hsu 한국물리학회 2010 Current Applied Physics Vol.10 No.2

We previously developed poly-N-vinyl-2-pyrrolidone (PVP)-capped Pt nanoclusters on ITO glass via a simple ‘‘2-step dip coating process” as counter electrode for DSSC. This new counter electrode was examined by transmission electron microscopy (TEM), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and current–voltage curve (I–V curve). The TEM results revealed that PVP-capped Pt nanoclusters’ size is about 3 nm, and the amount of Pt deposited on ITO glass is about 5 ㎍/㎠. Comparing with sputtered Pt and Solaronix thermal cluster Pt-catalyst T/SP, the PVP-capped Pt counter electrode has lower amount of Pt deposited on TCO glass,more positive potential of tri-iodide reduction, and better performance for the charge-transfer resistance (RCT) and the cell efficiency (g).

Maintenance of pegylated liposomal doxorubicin/carboplatin in patients with advanced ovarian cancer: randomized study of an Asian Gynecologic Oncology Group

Chyong-Huey Lai,Elizabeth Vallikad,Hao Lin,Lan-Yan Yang,Shih-Ming Jung,Hsueh-Erh Liu,Yu-Che Ou,Hung-Hsueh Chou,Cheng-Tao Lin,Huei-Jean Huang,Kuan-Gen Huang,Jiantai Qiu,Yao-Ching Hung,Tzu-I Wu,Wei-Yang 대한부인종양학회 2020 Journal of Gynecologic Oncology Vol.31 No.1

Objectives: An Asian Gynecologic Oncology Group phase III randomized trial was conducted to determine whether maintenance chemotherapy could improve progression-free survival (PFS) in stages III/IV ovarian cancer. Methods: Between 2007 and 2014, 45 newly-diagnosed ovarian cancer patients were enrolled after complete remission and randomized (1:1) to arm A (4-weekly carboplatin area under the curve 4 and pegylated liposomal doxorubicin [PLD] 30 mg/m2, n=24) for 6 cycles or arm B (observation, n=21). The primary end-point was PFS. A post hoc translational study was conducted to deep sequence BRCA/homologous recombination deficiency (HRD) genes, because BRCA/HRD mutations (BRCA/HRDm) are known to be associated with better prognosis. Results: Enrollment was slow, accrual was closed when 7+ years had passed. With a median follow-up of 88.9 months, the median PFS was significantly better in arm A (55.5 months) than arm B (9.2 months) (hazard ratio [HR]=0.40; 95% confidence interval [CI]=0.19–0.87; p=0.020), yet the median overall survival was not significantly different in arm A (not reached) than arm B (95.1 months) (p=0.148). Overall grade 3/4 adverse events were more frequent in arm A than arm B (60.9% vs 0.0%) (p<0.001). Quality of life was generally not significantly different. Distribution of BRCA1/2m or BRCA/HRDm was not significantly biased between the two arms. Wild-type BRCA/non-HRD subgroup seemed to fare better with maintenance therapy (HR=0.35; 95% CI=0.11–1.18; p=0.091). Conclusions: Despite limitations in small sample size, it suggests that maintenance carboplatin-PLD chemotherapy could improve PFS in advanced ovarian cancer.

Proton Pump Inhibitor-unresponsive Laryngeal Symptoms Are Associated With Psychological Comorbidities and Sleep Disturbance: A Manometry and Impedance-pH Monitoring Study

Wen-Hsuan Tseng,Wei-Chung Hsu,Tsung-Lin Yang,Tzu-Yu Hsiao,Jia-Feng Wu,Hui-Chuan Lee,Hsiu-Po Wang,Ming-Shiang Wu,Ming-Shiang Wu,Ping-Huei Tseng 대한소화기 기능성질환∙운동학회 2023 Journal of Neurogastroenterology and Motility (JNM Vol.29 No.3

Background/AimsLaryngeal symptoms are largely treated with empiric proton pump inhibitor (PPI) therapy if no apparent pathology shown on ear, nose, and throat evaluation and reflux-related etiologies are suspected. However, treatment response remains unsatisfactory. This study aimed to investigate the clinical and physiological characteristics of patients with PPI-refractory laryngeal symptoms. MethodsPatients with persistent laryngeal symptoms despite PPI treatment for ≥ 8 weeks were recruited. A multidisciplinary evaluation comprising validated questionnaires for laryngeal symptoms (reflux symptom index [RSI]), gastroesophageal reflux disease symptoms, psychological comorbidity (5-item brief symptom rating scale [BSRS-5]) and sleep disturbance (Pittsburgh sleep quality index [PSQI]), esophagogastroduodenoscopy, ambulatory impedance-pH monitoring, and high-resolution impedance manometry were performed. Healthy asymptomatic individuals were also recruited for comparison of psychological morbidity and sleep disturbances. ResultsNinety-seven adult patients and 48 healthy volunteers were analyzed. The patients had markedly higher prevalence of psychological distress (52.6% vs 2.1%, P < 0.001) and sleep disturbance (82.5% vs 37.5%, P < 0.001) than the healthy volunteers. There were significant correlations between RSI and BSRS-5 scores, and between RSI and PSQI scores (r = 0.26, P = 0.010, and r = 0.29, P = 0.004, respectively). Fifty-eight patients had concurrent gastroesophageal reflux disease symptoms. They had more prominent sleep disturbances (89.7% vs 71.8%, P < 0.001) than those with laryngeal symptoms alone but similar reflux profiles and esophageal motility. ConclusionsPPI-refractory laryngeal symptoms are mostly associated with psychological comorbidities and sleep disturbances. Recognition of these psychosocial comorbidities may help optimize management in these patients.

Abstract : Arsenic sequestration in iron plaque and its effect on As uptake by rice plants grown in paddy soils with high contents of As, iron oxides, and organic matter

( Chien Hui Syu ),( Pei Yu Jiang ),( Hsuan Han Huang ),( Wen Ting Chen ),( Tzu Huei Lin ),( Dar Yuan Lee ) 한국환경농학회 2012 한국환경농학회 워크샵자료 Vol.2012 No.2

The iron plaque formed on rice root has been confirmed to be a barrier on the uptake of arsenic in many hydroponic experiments. However, few studies provide the information about the relationship between soil characteristics, iron plaque formation and As uptake by rice in Ascontaminated soils. Therefore, the aim of this study is to investigate the effect of the rice root`s iron plaques on the As uptake by rice plants grown in geologically As-contaminated soils with high contents of iron oxides and organic matter from the Guandu Plain of northern Taiwan. A soil flooding incubation study was performed and a pot experiment was conducted. The rice seedling was pre-cultivated in solution cultures and then transplanted in three level As-contaminated soils for growing 39 days. The amounts of iron plaque on rice root were determined by extraction using dithionite-citrate-bicarbonate (DCB). The As species on iron plaque and the concentrations of As and Fe in iron plaque, root, root base and shoot of rice plants were determined. The results of the soil incubation study showed that both As and Fe concentrations in the soil solutions increased with flooding time due to reductive dissolution of iron oxides induced by high contents of organic matter in soils. High amounts of iron plaque were deposited on rice roots and large amounts of As were sequestrated in these iron plaques. Results of the As K-edge X-ray absorption nearedge spectroscopy (XANES) indicated that arsenate was the main species of arsenic sorbed on iron plaque of rice roots. About 74.0 to 93.2 % of total As released from soils were distributed in the iron plaques and only small proportion was distributed in the rice plants. This study provides evidence that the iron plaques of the rice roots was the main controlling factor in limiting the uptake and accumulation of As into the rice plants grown in paddy soils with high contents of iron oxides and organic matter, meanwhile, it suggests that enhancement of iron plaque formation could be the approach used for reducing the uptake of As by paddy rice grown in As-contaminated soils.