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1.  Ultra-Localized Single Cell Electroporation Using Silicon Nanowires 
Lab on a chip  2013;13(3):10.1039/c2lc40837f.
Analysis of cell-to-cell variation can further the understanding of intracellular processes and the role of individual cell function within a larger cell population. The ability to precisely lyse single cells can be used to release cellular components to resolve cellular heterogeneity that might be obscured when whole populations are examined. We report a method to position and lyse individual cells on silicon nanowire and nanoribbon biological field effect transistors. In this study, HT-29 cancer cells were positioned on top of transistors by manipulating magnetic beads using external magnetic fields. Ultra-rapid cell lysis was subsequently performed by applying 600–900 mVpp at 10 MHz for as little as 2 ms across the transistor channel and the bulk substrate. We show that the fringing electric field at the device surface disrupts the cell membrane, leading to lysis from irreversible electroporation. This methodology allows rapid and simple single cell lysis and analysis with potential applications in medical diagnostics, proteome analysis and developmental biology studies.
PMCID: PMC3535553  PMID: 23179093
2.  Pectinesterase Inhibitor from Jelly Fig (Ficus awkeotsang Makino) Achene Inhibits Surface Antigen Expression by Human Hepatitis B Virus 
Pectinesterase inhibitor (PEI) isolated from jelly fig (Ficus awkeotsang Makino) is an edible component of a popular drink consumed in Asia. Hepatitis B virus (HBV) infection is prevalent in Asia, and current treatments for HBV infection need improvement. This study aimed to evaluate the effect of PEI on the surface antigen expression by HBV (HBsAg). Human hepatoma cell lines Hep3B and Huh7 served as in vitro models for assessing the cytotoxicity and HBsAg expression. A culture of primary hepatocytes cultured from mice served as the normal counterpart. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. HBsAg expression was evaluated by measuring HBsAg secretion into the culture medium using an enzyme-linked immunosorbent assay. The results showed that PEI did not affect the viability of the human hepatoma cell lines or primary mouse hepatocytes. PEI inhibited the expression of HBsAg in hepatoma cell lines harboring endogenous (Hep3B) and integrated (Huh7) HBV genomes in a concentration- and time-dependent manner, thus implicating a universal activity against HBV gene expression. In conclusion, it suggests that PEI from jelly fig inhibits the expression of human HBsAg in host cells without toxic effects on normal primary hepatocytes.
PMCID: PMC3834976  PMID: 24302965
3.  Cardiopulmonary Profile in Streptozotocin-Induced Type 1 Diabetic Rats during Systemic Endotoxemia 
Journal of Diabetes Research  2013;2013:494179.
This study was designed to determine the severity of cardiopulmonary dysfunction during systemic endotoxemia in type 1 diabetes. Thirty-two adult male Wistar rats were randomly assigned to a control group or to a group treated with streptozotocin (STZ) to create an animal model of type 1 diabetes. Survival time and cardiovascular parameters were continually monitored in urethane anaesthetized animals receiving intravenous infusion of endotoxin (lipopolysaccharide (LPS)) or saline. We also determined arterial blood gases, lung injury, and tumor necrosis factor-alpha (TNF-α) levels in serum and bronchoalveolar lavage fluid. Before LPS administration, the mean arterial pressure in STZ rats was significantly higher than that in normal rats. After LPS injection, the heart rate drop significantly in STZ rats than that in the control group. Also, the increased levels of TNF-α in serum and lavage fluid after LPS treatment were significantly higher in STZ rats than those in normal rats. Survival time in STZ rats was shorter than that in normal rats after LPS application. Albumin content, wet/dry weight ratio of lung, and lung injury were indistinguishable between STZ and normal rats. These results indicate that the cardiopulmonary change which occurs during LPS-induced endotoxemia is minor in STZ-induced diabetic rats.
PMCID: PMC3647548  PMID: 23671873
4.  The novel application of artificial neural network on bioelectrical impedance analysis to assess the body composition in elderly 
Nutrition Journal  2013;12:21.
This study aims to improve accuracy of Bioelectrical Impedance Analysis (BIA) prediction equations for estimating fat free mass (FFM) of the elderly by using non-linear Back Propagation Artificial Neural Network (BP-ANN) model and to compare the predictive accuracy with the linear regression model by using energy dual X-ray absorptiometry (DXA) as reference method.
A total of 88 Taiwanese elderly adults were recruited in this study as subjects. Linear regression equations and BP-ANN prediction equation were developed using impedances and other anthropometrics for predicting the reference FFM measured by DXA (FFMDXA) in 36 male and 26 female Taiwanese elderly adults. The FFM estimated by BIA prediction equations using traditional linear regression model (FFMLR) and BP-ANN model (FFMANN) were compared to the FFMDXA. The measuring results of an additional 26 elderly adults were used to validate than accuracy of the predictive models.
The results showed the significant predictors were impedance, gender, age, height and weight in developed FFMLR linear model (LR) for predicting FFM (coefficient of determination, r2 = 0.940; standard error of estimate (SEE) = 2.729 kg; root mean square error (RMSE) = 2.571kg, P < 0.001). The above predictors were set as the variables of the input layer by using five neurons in the BP-ANN model (r2 = 0.987 with a SD = 1.192 kg and relatively lower RMSE = 1.183 kg), which had greater (improved) accuracy for estimating FFM when compared with linear model. The results showed a better agreement existed between FFMANN and FFMDXA than that between FFMLR and FFMDXA.
When compared the performance of developed prediction equations for estimating reference FFMDXA, the linear model has lower r2 with a larger SD in predictive results than that of BP-ANN model, which indicated ANN model is more suitable for estimating FFM.
PMCID: PMC3662169  PMID: 23388042
Back Propagation Artificial Neural Network (BP-ANN); Body composition; Bioelectrical impedance analysis (BIA); Elderly; Dual-energy X-ray absorptiometry
5.  Assessing Current Therapeutic Approaches to Decode Potential Resistance Mechanisms in Glioblastomas 
Unique astrocytic cell infiltrating growth and glial tumor growth in the confined skull make human glioblastoma (GBM) one of the most difficult cancers to treat in modern medicine. Prognosis for patients is very poor, as they die more or less within 12 months. Patients either die of the cancer itself, or secondary complications such as cerebral edema, herniations, or hemorrhages. GBMs rarely metastasize to other organs. However, GBM recurrence associated with resistance to therapeutic drugs is common. Patients die shortly after relapse. GBM is indeed an outstanding cancer model to search for potential mechanisms for drug resistance. Here, we reviewed the current cancer biology of gliomas and their pathophysiological events that contribute to the development of therapeutic resistance. We have addressed the potential roles of cancer stem cells, epigenetic modifications, and epithelial mesenchymal transition (EMT) in the development of resistance to inhibitor drugs in GBMs. The potential role of TIAF1 (TGF-β-induced antiapoptotic factor) overexpression and generation of intratumor amyloid fibrils for conferring drug resistance in GBMs is discussed.
PMCID: PMC3601334  PMID: 23516171
glioblastoma multiforme; temozolomide; resistance mechanisms; cancer stem cell; TIAF1 expression; extracellular matrix
6.  Lapatinib Induces Autophagy, Apoptosis and Megakaryocytic Differentiation in Chronic Myelogenous Leukemia K562 Cells 
PLoS ONE  2011;6(12):e29014.
Lapatinib is an oral, small-molecule, dual tyrosine kinase inhibitor of epidermal growth factor receptors (EGFR, or ErbB/Her) in solid tumors. Little is known about the effect of lapatinib on leukemia. Using human chronic myelogenous leukemia (CML) K562 cells as an experimental model, we found that lapatinib simultaneously induced morphological changes resembling apoptosis, autophagy, and megakaryocytic differentiation. Lapatinib-induced apoptosis was accompanied by a decrease in mitochondrial transmembrane potential and was attenuated by the pancaspase inhibitor z-VAD-fmk, indicating a mitochondria-mediated and caspase-dependent pathway. Lapatinib-induced autophagic cell death was verified by LC3-II conversion, and upregulation of Beclin-1. Further, autophagy inhibitor 3-methyladenine as well as autophagy-related proteins Beclin-1 (ATG6), ATG7, and ATG5 shRNA knockdown rescued the cells from lapatinib-induced growth inhibition. A moderate number of lapatinib-treated K562 cells exhibited features of megakaryocytic differentiation. In summary, lapatinib inhibited viability and induced multiple cellular events including apoptosis, autophagic cell death, and megakaryocytic differentiation in human CML K562 cells. This distinct activity of lapatinib against CML cells suggests potential for lapatinib as a therapeutic agent for treatment of CML. Further validation of lapatinib activity in vivo is warranted.
PMCID: PMC3245247  PMID: 22216158
7.  Increased expression of angiogenin in gastric carcinoma in correlation with tumor angiogenesis and proliferation 
AIM: To investigate the implication of angiogenin (ANG) in the neovascularizaton and growth of human gastric carcinoma (HGC).
METHODS: ANG mRNA expression in HGC specimens obtained by surgical resection from patients with HGC were examined by RT-PCR. ANG, Ki-67, VEGF protein expression and microvessel density (MVD) in HGC specimens were detected by immunohistochemistry.
RESULTS: RT-PCR showed significantly higher ANG mRNA expression (0.482 ± 0.094) in HGC tissues than in the surrounding nontumorous tissues (0.276 ± 0.019, P = 0.03). MVD within tumorous tissues increased significantly with ANG mRNA expression (r = 0.380, P = 0.001) and ANG protein expression (P < 0.01). The ANG expression levels of cancer tissues were positively correlated with VEGF (P < 0.01) and the proliferation index of cancer cells (P < 0.01).
CONCLUSION: ANG is one of the neovascularization factors of HGC. ANG may work in coordination with VEGF, and promote the proliferation of HGC cells.
PMCID: PMC4088009  PMID: 16937522
Angiogenin; Gastric carcinoma; Vascular endothelial growth factor; Angiogenesis
8.  Abnormal differentiation of dopaminergic neurons in zebrafish trpm7 mutant larvae impairs development of the motor pattern 
Developmental biology  2013;386(2):428-439.
Transient receptor potential, melastatin-like 7 (Trpm7) is a combined ion channel and kinase implicated in the differentiation or function of many cell types. Early lethality in mice and frogs depleted of the corresponding gene impedes investigation of the functions of this protein particularly during later stages of development. By contrast, zebrafish trpm7 mutant larvae undergo early morphogenesis normally and thus do not have this limitation. The mutant larvae are characterized by multiple defects including melanocyte cell death, transient paralysis, and an ion imbalance that leads to the development of kidney stones. Here we report a requirement for Trpm7 in differentiation or function of dopaminergic neurons in vivo. First, trpm7 mutant larvae are hypomotile and fail to make a dopamine-dependent developmental transition in swim-bout length. Both of these deficits are partially rescued by the application of levodopa or dopamine. Second, histological analysis reveals that in trpm7 mutants a significant fraction of dopaminergic neurons lack expression of tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis. Third, trpm7 mutants are unusually sensitive to the neurotoxin 1-methyl-4-phenylpyridinium, an oxidative stressor, and their motility is partially rescued by application of the iron chelator deferoxamine, an anti-oxidant. Finally, in SH-SY5Y cells, which model aspects of human dopaminergic neurons, forced expression of a channel-dead variant of TRPM7 causes cell death. In summary, a forward genetic screen in zebrafish has revealed that both melanocytes and dopaminergic neurons depend on the ion channel Trpm7. The mechanistic underpinning of this dependence requires further investigation.
PMCID: PMC3971878  PMID: 24291744
Parkinson’s; Zebrafish; Dopamine; TRPM7
9.  Application of air insufflation to prevent clinical pancreatic fistula after pancreaticoduodenectomy 
AIM: To introduce an air insufflation procedure and to investigate the effectiveness of air insufflation in preventing pancreatic fistula (PF).
METHODS: From March 2010 to August 2013, a total of 185 patients underwent pancreaticoduodenectomy (PD) at our institution, and 74 patients were not involved in this study for various reasons. The clinical outcomes of 111 patients were retrospectively analyzed. The air insufflation test was performed in 46 patients to investigate the efficacy of the pancreaticojejunal anastomosis during surgery, and 65 patients who did not receive the air insufflation test served as controls. Preoperative assessments and intraoperative outcomes were compared between the 2 groups. Univariate and multivariate analyses were performed to identify the risk factors for PF.
RESULTS: The two patient groups had similar baseline demographics, preoperative assessments, operative factors, pancreatic factors and pathological results. The overall mortality, morbidity, and PF rates were 1.8%, 48.6%, and 26.1%, respectively. No significant differences were observed in either morbidity or mortality between the two groups. The rate of clinical PF (grade B and grade C PF) was significantly lower in the air insufflation test group, compared with the non-air insufflation test group (6.5% vs 23.1%, P = 0.02). Univariate analysis identified the following parameters as risk factors related to clinical PF: estimated blood loss; pancreatic duct diameter ≤ 3 mm; invagination anastomosis technique; and not undergoing air insufflation test. By further analyzing these variables with multivariate logistic regression, estimated blood loss, pancreatic duct diameter ≤ 3 mm and not undergoing air insufflation test were demonstrated to be independent risk factors.
CONCLUSION: Performing an air insufflation test could significantly reduce the occurrence of clinical PF after PD. Not performing an air insufflation test was an independent risk factor for clinical PF.
PMCID: PMC4323465
Pancreatic fistula; Pancreaticoduodenectomy; Air insufflation test; Surgery; Morbidity
10.  A Prospective Study of Variability in Systolic Blood Pressure and Mortality in a Rural Bangladeshi Population Cohort 
Preventive medicine  2013;57(6):807-812.
Limited studies suggest that blood pressure variability over time is a risk factor of long-term cardiovascular outcomes. However, most of these were in populations with pre-existing CVD and studies in general population are lacking.
The study included 11,153 participants in a population-based, prospective cohort study in Araihazar, Bangladesh. Resting blood pressure was measured at baseline and every two years thereafter. Participants were followed-up for an average of 6.5 years (2002–2009).
Male gender, older age, baseline SBP, and absence of betel leaf use were independently positively associated with greater SBP variability over time. There was a significant association between SBP variability and the risk of death from overall CVD, especially from major CVD events. The positive association with the risk of death from any cause and stroke in age- and sex-adjusted models was attenuated in fully-adjusted models. In addition, the hazard ratio (HR) of stroke mortality was greater for individuals with both high baseline and high SBP variability. Similar patterns of HRs were observed for all-cause and CVD mortality.
In this rural Bangladeshi population, variability in SBP contributes to the risk of death from CVD and may further potentiate the increased mortality risk associated with high SBP.
PMCID: PMC4314716  PMID: 24051264
blood pressure; cardiovascular disease; cerebrovascular disorders; heart diseases; mortality; variability
11.  Real-time epidural anesthesia guidance using optical coherence tomography needle probe 
Epidural anesthesia is one of the most widely used anesthesia methods. Due to lack of visual feedback to guide needle navigation, failure rate of epidural anesthesia is up to 20%, and the complication rate of peripheral nerve block approaches 10%, with the potential of permanent nerve damage. To address these difficulties, needle insertion under ultrasound guidance and fluoroscopy has been introduced. However, they do not provide adequate resolution and contrast to distinguish the tissue layers that the needle travels through or to specifically identify the epidural space. To improve the accuracy of epidural space identification, we developed a small hand-held optical coherence tomography (OCT) forward-imaging needle device for real-time epidural anesthesia surgery guidance and demonstrated its feasibility through ex vivo and in vivo animal experiments. With tissue structures visualized and differentiated at the needle tip, OCT needle imaging device will enhance clinical outcomes with regards to complication rates, induced pain, and procedure failure when compared to standard practice. Furthermore, this technology could be used in combination with ultrasound/fluoroscopy to enhance outcomes.
PMCID: PMC4312299
Optical coherence tomography (OCT); epidural procedure; image-guided intervention
12.  Microcontroller-Assisted Compensation of Adenosine Triphosphate Levels: Instrument and Method Development 
Scientific Reports  2015;5:8135.
In order to ascertain optimum conditions for biocatalytic processes carried out in vitro, we have designed a bio-opto-electronic system which ensures real-time compensation for depletion of adenosine triphosphate (ATP) in reactions involving transfer of phosphate groups. The system covers ATP concentration range of 2–48 μM. The report demonstrates feasibility of the device operation using apyrase as the ATP-depleting enzyme.
PMCID: PMC4311256  PMID: 25633338
13.  Prolonged radiation time and low nadir hemoglobin during postoperative concurrent chemoradiotherapy are both poor prognostic factors with synergistic effect on locally advanced head and neck cancer patients 
OncoTargets and therapy  2015;8:251-258.
Anemia, a common complication of head and neck cancer treatment, is regarded as a poor prognostic factor. We evaluated the impact of low hemoglobin (Hb) levels, measured at different time points, on a consecutive cohort of patients with locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN) who underwent postoperative concurrent chemoradiotherapy (CCRT).
Materials and methods
From 2002 to 2009, 140 patients were enrolled and reviewed retrospectively. Preoperative (pre-op Hb), pre-CCRT Hb, and nadir Hb during CCRT were measured and recorded. The three Hb parameters were analyzed against several well-established pathologic risk factors and radiation-associated variables. Prognostic impacts were investigated with multivariate analysis by Cox proportional hazards model.
On Cox regression analysis, significantly higher risk of death was associated with pre-op Hb ≦13 g/dL (hazard ratio [HR] =1.8; 95% confidence interval [CI], 1.1–3.1; P=0.023), nadir Hb ≦11 g/dL (HR =1.9; 95% CI, 1.1–3.3; P=0.020), radiation treatment time (RTT) >7 weeks (HR =1.9; 95% CI, 1.1–3.3; P=0.022), and multiple positive lymph nodes (HR =2.1; 95% CI, 1.2–3.7; P=0.010), after adjusting for primary tumor site and pathologic lymphovascular invasion. Patients with poor prognosticators including low nadir Hb ≦11 g/dL and RTT >7 weeks had a higher risk of death (HR =4.0; 95% CI =1.6–10.2; P=0.004).
In the treatment setting of LA-SCCHN patients who underwent postoperative CCRT, coexistance of lower nadir Hb during CCRT and prolonged RTT resulted in reduced survival.
PMCID: PMC4315538
anemia; radiation time; concurrent chemoradiotherapy; hemoglobin; head and neck cancer
14.  Reduced Flexibility Associated with Metabolic Syndrome in Community-Dwelling Elders 
PLoS ONE  2015;10(1):e0117167.
The ageing process may lead to reductions in physical fitness, a known risk factor in the development of metabolic syndrome. The purpose of the current study was to evaluate cross-sectional and combined associations of metabolic syndrome with body composition and physical fitness in a community based geriatric population.
A total of 628 community-dwelling elders attending a geriatric health examination were enrolled in the study. The diagnosis of metabolic syndrome was based on the modified National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criterion with Asian cutoff of waist girth was adopted in this study. Body composition was obtained using bioimpedance analysis, and physical fitness was evaluated through the measurement of muscle strength (handgrip force), lower extremity muscle endurance (sit-to-stand test), flexibility (sit-and-reach test), and cardiorespiratory endurance (2-minute step test). Multivariable logistic regression and correlation analysis were performed to determine the association of metabolic syndrome with body composition and functionality variables.
Metabolic syndrome was associated with increased skeletal muscle index (SMI) (odds ratio (OR), 1.61, 95% confidence interval (CI), 1.25–2.07) and decreased flexibility (OR, 0.97, 95% CI, 0.95–0.99) compared with those without metabolic syndrome. When body mass index was accounted for in the analysis, the association of SMI with metabolic syndrome was reduced. Waist circumference was positively correlated with SMI but negatively correlated with flexibility, whereas high density lipoprotein was positively correlated with flexibility but negatively correlated with SMI.
Reduced flexibility was positively associated with metabolic syndrome independent of age, gender, body composition, and functionality measurements in a community based geriatric population. Significant associations between metabolic syndrome with muscle strength and cardiorespiratory fitness in the elderly were not observed. Furthermore, flexibility should be included in the complete evaluation for metabolic syndrome.
PMCID: PMC4304714  PMID: 25614984
15.  Identifying Chinese Herbal Medicine Network for Eczema: Implications from a Nationwide Prescription Database 
Eczema is a highly prevalent dermatological disease that can severely affect the patient's quality of life. Chinese herbal medicine (CHM) is commonly used in combination for eczema due to the complicated pathogenesis. This study aimed to identify a CHM network for the treatment of eczema by using a nationwide database. During 2011, 381,282 CHM prescriptions made for eczema (ICD-9-CM 692.x) were obtained from the National Health Insurance Research Database (NHIRD) in Taiwan and analyzed by using association rule mining and social network analysis. Among 661 available CHMs, 44 important combinations were identified. Among the CHM networks, seven clusters with the predominant traditional Chinese medicine (TCM) pattern were recognized. The largest CHM cluster was used to treat the wind-dampness-heat pattern, and Xiao-Feng-San (24.1% of all prescriptions) was the core of this cluster with anti-inflammation, antioxidation, and antiallergic effects. Lonicera japonica (11.0% of all prescriptions) with Forsythia suspense (17.0% of all prescriptions) was the most commonly used CHM combination and was also the core treatment for treating the heat pattern, in which an antimicrobial effect is found. CHM network analysis is helpful for TCM doctors or researchers to choose candidates for clinical practice or further studies.
PMCID: PMC4320894
16.  The prevalence and correlates of the positive Androgen Deficiency in the Aging Male (ADAM) questionnaire among psychiatric outpatients: a cross-sectional survey of 176 men in a general hospital in Taiwan 
The Androgen Deficiency in the Aging Male (ADAM) questionnaire is widely used to screen for late-onset hypogonadism. The positive response to the ADAM questionnaire (positive ADAM) has been associated with depression and poorer quality of life in a number of studies. It is unclear whether there is any value of the ADAM questionnaire in psychiatric populations. In this study, we aimed to determine the utility of the ADAM questionnaire in a convenient sample of male psychiatric outpatients.
One hundred and seventy-six men (mean age: 54.3 years; standard deviation: 10.7 years; range: 40–80 years) completed the ADAM questionnaire, the Hospital Anxiety and Depression Scale (HADS), and the Aging Males’ Symptoms (AMS) scale. Anxiety was defined as a HADS anxiety subscore ≥8; depression as a HADS depression subscore ≥8; and moderate/severe impairment of health-related quality of life (HQoL) as AMS ≥37. ADAM, anxiety, and depression was used to model the moderate/severe impairment of HQoL.
One hundred and sixty-four (93%) men had positive ADAM. Positive ADAM was associated with a lower body mass index (P<0.05) and moderate/severe impairment of HQoL (P<0.001), but was not associated with anxiety or depression (P>0.05). Positive ADAM was associated with five symptoms of the AMS scale: “decline of one’s feeling of general well-being”, “depressive mood”, and three sexual symptoms. In regression analysis, positive ADAM was associated with increased risk of moderate/severe impairment of HQoL (unadjusted odds ratio 20.1, 95% confidence interval 3.77–372, P<0.01), which remained significant with covariates of anxiety and depression (adjusted odds ratio 15.6, 95% confidence interval 2.52–309, P<0.05).
The ADAM questionnaire can be used to screen the sexual symptoms but not depression/anxiety in male psychiatric outpatients. Positive ADAM may indicate moderate/severe impairment of HQoL.
PMCID: PMC4309773  PMID: 25653527
Aging Males’ Symptoms scale; anxiety; depression; health-related quality of life
17.  Oxysterols direct immune cell migration through EBI2 
Nature  2011;475(7357):524-527.
Epstein-Barr virus (EBV)-induced gene 2 (EBI2, aka GPR183) is a G protein-coupled receptor that is required for humoral immune responses and polymorphisms in the receptor have been associated with inflammatory autoimmune diseases1-3. The natural ligand for EBI2 has been unknown. Here we describe identification of 7α, 25-dihydroxycholesterol (5-cholesten-3β, 7α, 25-triol; 7α, 25-OHC) as a potent and selective agonist of EBI2. Functional activation of EBI2 by 7α, 25-OHC and closely related oxysterols was verified by monitoring second messenger readouts and saturable, high affinity radioligand binding. Furthermore we find that 7α, 25-OHC and closely related oxysterols act as chemoattractants for immune cells expressing EBI2 by directing cell migration in vitro and in vivo. A key enzyme required for the generation of 7α, 25-OHC is cholesterol 25-hydroxylase (Ch25h)4. Similar to EBI2 receptor knockout mice, mice deficient in Ch25h fail to position activated B cells within the spleen to the outer follicle and mount a reduced plasma cell response after an immune challenge. This demonstrates that Ch25h generates EBI2 bioactivity in vivo and suggests that the EBI2 − oxysterol signaling pathway plays an important role in the adaptive immune response.
PMCID: PMC4297623  PMID: 21796212
18.  Metabolism of Albumin after Continuous Venovenous Hemofiltration in Patients with Systemic Inflammatory Response Syndrome 
BioMed Research International  2015;2015:917674.
Background. The systemic inflammatory response syndrome (SIRS) is characterized by a hypercatabolic state induced by inflammatory mediators. Continuous venovenous hemofiltration (CVVH) stabilizes the internal environment but also aggravates loss of amino acids. The effect of CVVH on protein dynamics is largely unknown. We adopted the stable isotopic tracer technology to investigate how CVVH changed serum albumin metabolism. Methods. Twenty SIRS patients were randomized into low- (2000 mL/h) and high- (4000 mL/h) volume CVVH groups according to the rate of replacement fluid. Eight patients with abdominal infection matched for age, sex, and laboratory index served as controls. Consecutive arterial blood samples were drawn during a primed-constant infusion of two stable isotopes to determine the albumin fractional synthesis rate (FSR) and fractional breakdown rate (FBR). Results. Before treatment, there was no significant difference of FSR and FBR among 3 groups. After CVVH, the albumin FSR in high- and low-volume groups was 7.75 ± 1.08% and 7.30 ± 0.89%, respectively, both higher than in the control (5.83 ± 0.94%). There was no significant difference in albumin FBR after treatment. Conclusions. Protein dynamic indicators could reflect protein synthesis and breakdown state directly and effectively. CVVH increased albumin synthesis, while the breakdown rate remained at a high level independently of the CVVH rate.
PMCID: PMC4310232  PMID: 25650044
19.  EGLN2 and RNF150 genetic variants are associated with chronic obstructive pulmonary disease risk in the Chinese population 
Chronic obstructive pulmonary disease (COPD) is a major and an increasingly prevalent health problem worldwide. It has been reported that genetic variation may play a role in the development and severity of COPD. The purpose of this study was to investigate whether single nucleotide polymorphisms in multiple genetic variants were associated with COPD in a Chinese population from Hainan province.
In this case-control study, including 200 COPD patients and 401 controls, we genotyped 14 tag single nucleotide polymorphisms and evaluated their association with COPD using the χ2 test and genetic model analysis.
The polymorphism, rs10007052, in the RNF150 gene was significantly associated with COPD risk at a 5% level (odds ratio =1.43, 95% confidence interval, 1.06–1.95, P=0.020). In the log-additive model, the minor allele (C) of rs10007052 in the RNF150 gene (P=0.026) and the minor allele (C) of rs3733829 in the EGLN2 gene (P=0.037) were associated with COPD risk after adjustment for age, sex, and smoking status. Further haplotype analysis revealed that the “CT” haplotype composed of the mutant allele (C) of rs7937, rs3733829 in the EGLN2 gene, was associated with increased COPD risk (odds ratio =1.55; 95% confidence interval, 1.05–2.31; P=0.029).
Our findings indicated that rs10007052 in the RNF150 and rs3733829 in the EGLN2 gene were significantly associated with the risk of COPD in Chinese populations of Hainan province. These data may provide novel insights into the pathogenesis of COPD, although further studies with larger numbers of participants worldwide are needed for validation of our conclusions.
PMCID: PMC4298296  PMID: 25609945
case-control studies; COPD; tag single-nucleotide polymorphism
20.  Pretreatment platelet count as a predictor for survival and distant metastasis in nasopharyngeal carcinoma patients 
Oncology Letters  2015;9(3):1458-1466.
The aim of the present study was to investigate the prognostic value of different pretreatment platelet (PLT) counts on the treatment outcome in nasopharyngeal carcinoma (NPC) patients receiving concurrent chemoradiotherapy (CCRT) or radiotherapy (RT) alone. A total of 1,501 NPC patients, including 412 receiving CCRT and 1,089 receiving RT, were enrolled in the present study. The PLT count cut-off points for the CCRT and RT groups were 150 and 300×109/l, respectively, and the PLT counts were categorized it into three groups: Low (PLT≤150×109/l), moderate (150×109/l300×109/l). To identify independent predictors of overall survival (OS), the Cox proportional hazards model was used to determine local-regional recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS) rates in the CCRT and RT patients. Furthermore, univariate and multivariate analysis indicated that compared with a moderate PLT count, a low PLT count was an independent unfavorable prognostic factor for OS rate in CCRT patients [hazard ratio (HR), 2.024; 95% confidence interval (CI), 1.165–3.516], and a high PLT count was an independent unfavorable prognostic factor for OS and DMFS rates in CCRT (OS: HR, 1.742; 95% CI, 1.090–2.786; DFMS: HR, 2.110; 95%CI, 1.084–4.108) and RT (OS: HR, 1.740; 95%CI, 1.283–2.362; DMFS: HR, 2.819; 95% CI, 1.766–4.497) patients. Compared with a low PLT count, a high PLT count was significantly and independently associated with a poor DMFS rate in the RT patients (P=0.025; HR, 2.454; 95% CI, 1.121–5.372). Therefore, the present study indicates that low and high PLT counts may be useful indicators of survival and distant metastasis in NPC patients who have undergone radiation treatment.
PMCID: PMC4314978  PMID: 25663931
platelet count; nasopharyngeal carcinoma; radiotherapy; concurrent chemoradiotherapy; predictor; prognosis
21.  Numerical simulation on the effects of drug eluting stents at different Reynolds numbers on hemodynamic and drug concentration distribution 
BioMedical Engineering OnLine  2015;14(Suppl 1):S16.
The changes of hemodynamics and drug concentration distribution caused by the implantation of drug eluting stents (DESs) in curved vessels have significant effects on In-Stent Restenosis.
A 3D virtual stent with 90°curvature was modelled and the distribution of wall shear stress (WSS) and drug concentration in this model were numerically studied at Reynolds numbers of 200, 400, 600, 800.
The results showed that (1) the intensity of secondary flow at the 45° cross-section was stronger than that at the 90° cross-section; (2) As the Reynolds number increases, the WSS decreases. When the Reynolds number reaches 600, the low-WSS region only accounts for 3% of the total area. (3) The effects of Reynolds number on drug concentration in the vascular wall decreases in proportionally and then the blood velocity increased 4 times, the drug concentration in the vascular wall decreased by about 30%. (4) The size of the high drug concentration region is inversely proportional to the Reynolds number. As the blood velocity increases, the drug concentration in the DES decreases, especially at the outer bend.
It is beneficial for the patient to decrease vigorous activities and keep calm at the beginning of the stent implantation, because a substantial amount of the drug is released in the first two months of stent implantation, thus a calm status is conducive to drug release and absorption; Subsequently, appropriate exercise which increases the blood velocity is helpful in decreasing regions of low-WSS.
PMCID: PMC4306105  PMID: 25602685
DES; curved artery; secondary flow; Reynolds number; WSS; drug concentration
22.  MEG Source Imaging Method using Fast L1 Minimum-norm and its Applications to Signals with Brain Noise and Human Resting-state Source Amplitude Images 
NeuroImage  2013;84:585-604.
The present study developed a fast MEG source imaging technique based on Fast Vector-based Spatio-Temporal Analysis using a L1-minimum-norm (Fast-VESTAL) and then used the method to obtain the source amplitude images of resting-state magnetoencephalography (MEG) signals for different frequency bands. The Fast-VESTAL technique consists of two steps. First, L1-minimum-norm MEG source images were obtained for the dominant spatial modes of sensor-waveform covariance matrix. Next, accurate source time-courses with millisecond temporal resolution were obtained using an inverse operator constructed from the spatial source images of Step 1. Using simulations, Fast-VESTAL’s performance of was assessed for its 1) ability to localize multiple correlated sources; 2) ability to faithfully recover source time-courses; 3) robustness to different SNR conditions including SNR with negative dB levels; 4) capability to handle correlated brain noise; and 5) statistical maps of MEG source images. An objective pre-whitening method was also developed and integrated with Fast-VESTAL to remove correlated brain noise. Fast-VESTAL’s performance was then examined in the analysis of human mediannerve MEG responses. The results demonstrated that this method easily distinguished sources in the entire somatosensory network. Next, Fast-VESTAL was applied to obtain the first whole-head MEG source-amplitude images from resting-state signals in 41 healthy control subjects, for all standard frequency bands. Comparisons between resting-state MEG sources images and known neurophysiology were provided. Additionally, in simulations and cases with MEG human responses, the results obtained from using conventional beamformer technique were compared with those from Fast-VESTAL, which highlighted the beamformer’s problems of signal leaking and distorted source time-courses.
PMCID: PMC4096863  PMID: 24055704
minimum norm; L1-norm; resting-state; median-nerve; brain noise; beamformer
23.  The use of the reinstatement model to study relapse to palatable food seeking during dieting 
Neuropharmacology  2013;76(0 0):10.1016/j.neuropharm.2013.04.030.
Excessive consumption of unhealthy foods is a major public health problem. While many people attempt to control their food intake through dieting, many relapse to unhealthy eating habits within a few months. We have begun to study this clinical condition in rats by adapting the reinstatement model, which has been used extensively to study relapse to drug seeking. In our adaptation of the relapse model, reinstatement of palatable food seeking by exposure to food-pellet priming, food-associated cues, or stress is assessed in food-restricted (to mimic dieting) rats after operant food-pellet self-administration training and subsequent extinction of the food-reinforced responding.
In this review, we first outline the clinical problem and discuss a recent study in which we assessed the predictive validity of the reinstatement model for studying relapse to food seeking during dieting by using the anorexigenic drug fenfluramine. Next, we summarize results from our initial studies on the role of several stress- and feeding-related peptides (corticotropin-releasing factor, hypocretin, melanin- concentrating hormone, peptide YY3-36) in reinstatement of palatable food seeking. We then present results from our studies on the role of dopamine and medial prefrontal cortex in stress-induced reinstatement of food seeking. We conclude by discussing potential clinical implications.
We offer two main conclusions: (1) the food reinstatement model is a simple, reliable, and valid model to study mechanisms of relapse to palatable food seeking during dieting, and to identify medications to prevent this relapse; (2) mechanisms of relapse to food seeking are often dissociable from mechanisms of ongoing food intake.
PMCID: PMC3785569  PMID: 23660229
food; relapse; stress; priming; cue; reinstatement; dieting; self-administration
24.  Association between anthropometric measures of obesity and subclinical atherosclerosis in Bangladesh 
Atherosclerosis  2013;232(1):234-241.
Anthropometric measures such as waist-hip-ratio (WHR), waist-height-ratio (WHtR), waist circumference, Mid-upper arm circumference (MUAC), and upper thigh circumference, have been linked to the risk of cardiovascular disease (CVD). However, their relationships with subclinical atherosclerosis are unclear. Studies in normal-weight populations, especially in Asian countries where leanness is prevalent, are lacking.
We conducted a cross-sectional study to assess the associations of WHR, WHtR, waist circumference, hip circumference, body mass index (BMI), MUAC and upper thigh circumference with carotid intima-media thickness (cIMT) among 562 middle-aged participants free of CVD in rural Bangladesh.
After adjusting for age and sex, WHR and waist circumference but not BMI showed a positive significant association with cIMT. In multivariate analysis, each standard deviation (SD) increase of WHR (0.08) or WHtR (0.07) was associated with an 8.96 μm (95% CI, 1.12–16.81) or 11.45 μm (95%CI, 0.86–22.04) difference in cIMT, respectively, after controlling for age, sex, BMI, smoking status, education level, and systolic blood pressure (SBP). The associations of WHR and WHtR with cIMT were independent of the influence of other anthropometric measures. The associations of other anthropometric measures and cIMT were not apparent.
In our relatively lean, healthy Asian population, WHR and WHtR appear to be better predictors of early atherosclerosis than other common surrogates of adiposity.
PMCID: PMC3888510  PMID: 24401245
25.  Fragment-based inhibitor discovery against β-lactamase 
Future medicinal chemistry  2014;6(4):413-427.
The production of β-lactamase is one of the primary resistance mechanisms used by Gram-negative bacterial pathogens to counter β-lactam antibiotics, such as penicillins, cephalosporins and carbapenems. There is an urgent need to develop novel β-lactamase inhibitors in response to ever evolving β-lactamases possessing an expanded spectrum of β-lactam hydrolyzing activity. Whereas traditional high-throughput screening has proven ineffective against serine β-lactamases, fragment-based approaches have been successfully employed to identify novel chemical matter, which in turn has revealed much about the specific molecular interactions possible in the active site of serine and metallo β-lactamases. In this review, we summarize recent progress in the field, particularly: the identification of novel inhibitor chemotypes through fragment-based screening; the use of fragment-protein structures to understand key features of binding hot spots and inform the design of improved leads; lessons learned and new prospects for β-lactamase inhibitor development using fragment-based approaches.
PMCID: PMC4111090  PMID: 24635522

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