Displaying publications 41 - 60 of 190 in total

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  1. Gou Z, Ma NL, Zhang W, Lei Z, Su Y, Sun C, et al.
    Environ Res, 2020 09;188:109829.
    PMID: 32798948 DOI: 10.1016/j.envres.2020.109829
    Intensive studies have been performed on the improvement of bioethanol production by transformation of lignocellulose biomass. In this study, the digestibility of corn stover was dramatically improved by using laccase immobilized on Cu2+ modified recyclable magnetite nanoparticles, Fe3O4-NH2. After digestion, the laccase was efficiently separated from slurry. The degradation rate of lignin reached 40.76%, and the subsequent cellulose conversion rate 38.37% for 72 h at 35 °C with cellulase at 50 U g-1 of corn stover. Compared to those of free and inactivated mode, the immobilized laccase pre-treatment increased subsequent cellulose conversion rates by 23.98% and 23.34%, respectively. Moreover, the reusability of immobilized laccase activity remained 50% after 6 cycles. The storage and thermal stability of the fixed laccase enhanced by 70% and 24.1% compared to those of free laccase at 65 °C, pH 4.5, respectively. At pH 10.5, it exhibited 16.3% more activities than its free mode at 35 °C. Our study provides a new avenue for improving the production of bioethanol with immobilized laccase for delignification using corn stover as the starting material.
  2. Xu D, Yang L, Zhao M, Zhang J, Syed-Hassan SSA, Sun H, et al.
    Environ Pollut, 2021 Feb 01;270:116120.
    PMID: 33341552 DOI: 10.1016/j.envpol.2020.116120
    Understanding the migration and conversion of nitrogen in wood-based panels (WBPs) during pyrolysis is fundamentally important for potentially transforming the N-containing species into valuable material-based products. This review firstly summarizes the commonly used methods for examining N evolution during the WBPs pyrolysis before probing into the association between the wood and adhesives.The potential effects of wood-adhesive interaction on the pyrolysis process are subsequently analyzed. Furthermore, the controversial statements from literature on the influence of adhesives on wood pyrolysis behavior are discussed, which is followed by the detailed investigation into the distribution and evolution of N-containing species in gas, liquid and char, respectively, during WBPs pyrolysis in recent studies. The differences in N species due to the heating sources (i.e. electrical heating vs microwave heating) are particularly compared. Finally, based on the characteristics of staged pyrolysis, co-pyrolysis and catalytic pyrolysis, the converting pathways for WBPs are proposed with an emphasis on the production of value-added chemicals and carbon materials, simultaneously mitigating NOx emission.
  3. Chen W, Li Y, Xue W, Shahabi H, Li S, Hong H, et al.
    Sci Total Environ, 2020 Jan 20;701:134979.
    PMID: 31733400 DOI: 10.1016/j.scitotenv.2019.134979
    Floods are one of the most devastating types of disasters that cause loss of lives and property worldwide each year. This study aimed to evaluate and compare the prediction capability of the naïve Bayes tree (NBTree), alternating decision tree (ADTree), and random forest (RF) methods for the spatial prediction of flood occurrence in the Quannan area, China. A flood inventory map with 363 flood locations was produced and partitioned into training and validation datasets through random selection with a ratio of 70/30. The spatial flood database was constructed using thirteen flood explanatory factors. The probability certainty factor (PCF) method was used to analyze the correlation between the factors and flood occurrences. Consequently, three flood susceptibility maps were produced using the NBTree, ADTree, and RF methods. Finally, the area under the curve (AUC) and statistical measures were used to validate the flood susceptibility models. The results indicated that the RF method is an efficient and reliable model in flood susceptibility assessment, with the highest AUC values, positive predictive rate, negative predictive rate, sensitivity, specificity, and accuracy for the training (0.951, 0.892, 0.941, 0.945, 0.886, and 0.915, respectively) and validation (0.925, 0.851, 0.938, 0.945, 0.835, and 0.890, respectively) datasets.
  4. Xu D, Gao Y, Lin Z, Gao W, Zhang H, Karnowo K, et al.
    Front Chem, 2019;7:943.
    PMID: 32117859 DOI: 10.3389/fchem.2019.00943
    In this study, biochars derived from waste fiberboard biomass were applied in tetracycline (TC) removal in aqueous solution. Biochar samples were prepared by slow pyrolysis at 300, 500, and 800°C, and were characterized by ultimate analysis, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), etc. The effects of ionic strength (0-1.0 mol/L of NaCl), initial TC concentration (2.5-60 ppm), biochar dosage (1.5-2.5 g/L), and initial pH (2-10) were systemically determined. The results present that biochar prepared at 800°C (BC800) generally possesses the highest aromatization degree and surface area with abundant pyridinic N (N-6) and accordingly shows a better removal efficiency (68.6%) than the other two biochar samples. Adsorption isotherm data were better fitted by the Freundlich model (R2 is 0.94) than the Langmuir model (R2 is 0.85). Thermodynamic study showed that the adsorption process is endothermic and mainly physical in nature with the values of ΔH0 being 48.0 kJ/mol, ΔS0 being 157.1 J/mol/K, and ΔG0 varying from 1.02 to -2.14 kJ/mol. The graphite-like structure in biochar enables the π-π interactions with a ring structure in the TC molecule, which, together with the N-6 acting as electron donor, is the main driving force of the adsorption process.
  5. Huang Y, Liu S, Zhang J, Syed-Hassan SSA, Hu X, Sun H, et al.
    Bioresour Technol, 2020 Jul;307:123192.
    PMID: 32220819 DOI: 10.1016/j.biortech.2020.123192
    This study investigated the interactions between volatile and char during biomass pyrolysis at 400 °C, employing a β-5 lignin dimer and amino-modified graphitized carbon nanotube (CNT-NH2) as their models, respectively. The results demonstrated that both -NH2 and its carrier (CNT) facilitated the conversion of the β-5 dimer, which significantly increased from 9.7% (blank run), to 61.6% (with CNT), and to 96.6% (with CNT-NH2). CNT mainly favored the breakage of C-O bond in the feedstock to produce dimers with a yield of 55.5%, while CNT-NH2 promoted the cleavage of both C-O and C-C bonds to yield monomers with a yield up to 63.4%. Such significant changes in the pyrolysis behaviors of the β-5 lignin dimer after the introduction of CNT-NH2 were considered to be mainly caused by hydrogen-bond formations between -NH2 and the dimeric feedstock/products, in addition to the π-π stacking between CNT and aromatic rings.
  6. Jin H, Wang Y, Zhao P, Wang L, Zhang S, Meng D, et al.
    J Agric Food Chem, 2021 Oct 27;69(42):12385-12401.
    PMID: 34649432 DOI: 10.1021/acs.jafc.1c04632
    Numerous plant secondary metabolites have remarkable impacts on both food supplements and pharmaceuticals for human health improvement. However, higher plants can only generate small amounts of these chemicals with specific temporal and spatial arrangements, which are unable to satisfy the expanding market demands. Cyanobacteria can directly utilize CO2, light energy, and inorganic nutrients to synthesize versatile plant-specific photosynthetic intermediates and organic compounds in large-scale photobioreactors with outstanding economic merit. Thus, they have been rapidly developed as a "green" chassis for the synthesis of bioproducts. Flavonoids, chemical compounds based on aromatic amino acids, are considered to be indispensable components in a variety of nutraceutical, pharmaceutical, and cosmetic applications. In contrast to heterotrophic metabolic engineering pioneers, such as yeast and Escherichia coli, information about the biosynthesis flavonoids and their derivatives is less comprehensive than that of their photosynthetic counterparts. Here, we review both benefits and challenges to promote cyanobacterial cell factories for flavonoid biosynthesis. With increasing concerns about global environmental issues and food security, we are confident that energy self-supporting cyanobacteria will attract increasing attention for the generation of different kinds of bioproducts. We hope that the work presented here will serve as an index and encourage more scientists to join in the relevant research area.
  7. Foo YH, Ratnam S, Lim EV, Abdullah M, Molenaar VJ, Shau Hwai AT, et al.
    PeerJ, 2022;10:e13181.
    PMID: 35462757 DOI: 10.7717/peerj.13181
    Over the past decade, concerns over microplastic pollution in the marine ecosystem has increasingly gained more attention, but research investigating the ingestion of microplastics by marine fish in Malaysia is still regrettably lacking. This study investigated the microplastic presence, abundance, and morphological types within the guts of four species of commercial marine fish (Atule mate, Crenimugil seheli, Sardinella fimbriata and Rastrelliger brachysoma) caught in seawater off the coast of Malaysia's Northwest Peninsular. A total of 72 individual commercial marine fish guts from four species (fish per species n = 18) were examined. Remarkably, this study found that 100% of the samples contained microplastics. A total number of 432 microplastics (size < 5 mm) from the four species were found in the excised marine fish guts. The most common type of microplastic discovered was fragment, which accounted for 49.5% of all microplastics present. The gut microplastic content differed between species. Sardinella fimbriata recorded the greatest amount of microplastic ingestion, with an average microplastic count of 6.5 (±4.3) items per individual fish. However, there were no statistically significant differences found when comparing study species and different locations. SEM-EDX analysis confirmed the presence of microplastic particles by identifying the chemical elements found in the samples. Since the four studied species of commercial marine fish are popular protein sources in Malaysians' daily diet, this study suggests potential microplastic exposure to humans via contaminated fish consumption in Malaysia, which was previously unknown. Based on previous scientific evidence, this study also demonstrates the high probability of microplastic ingestion in marine fish in the Malaysian seawater, which could have an adverse effect on fish health as well as marine biota.
  8. Zhang S, Chong LH, Woon JYX, Chua TX, Cheruba E, Yip AK, et al.
    Commun Biol, 2023 Jan 18;6(1):62.
    PMID: 36653484 DOI: 10.1038/s42003-023-04421-0
    Biochemical signaling and mechano-transduction are both critical in regulating stem cell fate. How crosstalk between mechanical and biochemical cues influences embryonic development, however, is not extensively investigated. Using a comparative study of focal adhesion constituents between mouse embryonic stem cell (mESC) and their differentiated counterparts, we find while zyxin is lowly expressed in mESCs, its levels increase dramatically during early differentiation. Interestingly, overexpression of zyxin in mESCs suppresses Oct4 and Nanog. Using an integrative biochemical and biophysical approach, we demonstrate involvement of zyxin in regulating pluripotency through actin stress fibres and focal adhesions which are known to modulate cellular traction stress and facilitate substrate rigidity-sensing. YAP signaling is identified as an important biochemical effector of zyxin-induced mechanotransduction. These results provide insights into the role of zyxin in the integration of mechanical and biochemical cues for the regulation of embryonic stem cell fate.
  9. Mak KK, Zhang S, Chellian J, Mohd Z, Epemolu O, Dinkova-Kostova AT, et al.
    Antioxidants (Basel), 2023 Feb 27;12(3).
    PMID: 36978843 DOI: 10.3390/antiox12030595
    Our previous studies have reported the effect of swietenine (a major bioactive component of Swietenia macrophylla seeds) in reversing and potentiating the effect of metformin in hyperglycemia and hyperlipidaemia in diabetic rats. Moreover, we reported that the anti-inflammatory effect of swietenine is mediated via the activation of nuclear factor erythroid 2-related factor 2 (Nrf2). This study evaluated the effect of swietenine and its mechanisms in nonalcoholic fatty liver disease (NAFLD) in high-fat diet/streptozotocin-induced diabetic mice. The effect was assessed by determining blood biochemical parameters (glucose, cholesterol, triglycerides, alanine transaminase (ALT), asparate transaminase (AST), alkaline phosphatase (ALP), glutathione (GSH), total antioxidant capacity (TAC), and malondialdehyde (MDA)) and liver biochemical parameters (liver index, cholesterol, and triglycerides). Hepatic lipid accumulation (initial causative factor in NAFLD) was determined by oil-O-red staining. Gene expression (qPCR) and immunohistochemical studies were performed to elucidate the mechanism of swietenine's effect in NAFLD. The critical regulators (genes and proteins) involved in lipogenesis (ACLY, ACC1, FASN, SREBP1c, and ChREBPβ) and oxidative stress (Nrf2, NQO-1 and HO-1) pathways were determined. In mice fed with a high-fat diet followed by streptozotocin injection, the liver cholesterol, triglycerides, and lipids were elevated. These increases were reversed by the oral administration of swietenine, 80 mg/kg body weight, on alternate days for eight weeks. Gene expression and immunohistochemical studies showed that swietenine reversed the elevated levels of crucial enzymes of lipogenesis (ACLY, ACC1 and FASN) and their master transcription factors (SREBP1c and ChREBPβ). Furthermore, swietenine activated the Nrf2 antioxidant defense mechanism, as evidenced by the upregulated levels of Nrf2, NQO-1, and HO-1. It is concluded that swietenine shows beneficial effects in diabetes-induced NAFLD via inhibiting lipogenesis and activating the Nrf2 pathway.
  10. Hamid HA, Lin X, Qin YK, Akim AM, Zhang L, Wang J, et al.
    Int Wound J, 2024 Feb;21(2):e14574.
    PMID: 38379231 DOI: 10.1111/iwj.14574
    This cross-sectional study was conducted to examine the most effective strategies for managing malodorous and infected wounds in patients who have been diagnosed with advanced cervical cancer. The research was conducted in Liupanshui, China. The study specifically examined demographic profiles, wound characteristics and effectiveness of wound management approaches. The study incorporated the heterogeneous sample of 289 participants who fulfilled the inclusion criteria. Data collection was conducted via structured questionnaires and medical record evaluations. Descriptive statistics and statistical analyses, such as regression analysis, were utilized to evaluate demographic attributes, wound profiles and effects of different approaches to wound management. The findings unveiled the heterogeneous demographic composition of patients, encompassing differences in socioeconomic standing, educational attainment and age. A wide range of wound characteristics were observed, as 65.7% of lesions during the acute phase with diameter between 2 and 5 centimetres, while 41.5% of lesions had this range. The most prevalent types of infections were those caused by fungi (48.4%), followed by bacterial infections lacking resistance (38.1%). A moderate degree of odour intensity was prevalent, affecting 45.0% of the cases. With maximal odour reduction of 80%, a mean healing time of 25 days and patient satisfaction rating of 4.5 out of 5, Negative Pressure Wound Therapy demonstrated itself to be the most efficacious treatment method. Additional approaches, such as photodynamic therapy and topical antibiotic therapy, demonstrated significant effectiveness, as evidenced by odour reductions of 70% and 75%, respectively, and patient satisfaction ratings of 4.3 and 4.2. Thus, the study determined challenges associated with management of malodorous and infected lesions among patients with advanced cervical cancer. The results underscored the significance of individualized care approaches, drew attention to efficacious wound management techniques and identified critical determinants that impacted patient recuperation. The findings of this study hold potential for advancing palliative care for individuals diagnosed with advanced cervical cancer.
  11. Chen X, Tan X, Li J, Jin Y, Gong L, Hong M, et al.
    PLoS One, 2013;8(12):e82861.
    PMID: 24340064 DOI: 10.1371/journal.pone.0082861
    Coxsackievirus A16 (CVA16) is responsible for nearly 50% of all the confirmed hand, foot, and mouth disease (HFMD) cases in mainland China, sometimes it could also cause severe complications, and even death. To clarify the genetic characteristics and the epidemic patterns of CVA16 in mainland China, comprehensive bioinfomatics analyses were performed by using 35 CVA16 whole genome sequences from 1998 to 2011, 593 complete CVA16 VP1 sequences from 1981 to 2011, and prototype strains of human enterovirus species A (EV-A). Analysis on complete VP1 sequences revealed that subgenotypes B1a and B1b were prevalent strains and have been co-circulating in many Asian countries since 2000, especially in mainland China for at least 13 years. While the prevalence of subgenotype B1c (totally 20 strains) was much limited, only found in Malaysia from 2005 to 2007 and in France in 2010. Genotype B2 only caused epidemic in Japan and Malaysia from 1981 to 2000. Both subgenotypes B1a and B1b were potential recombinant viruses containing sequences from other EV-A donors in the 5'-untranslated region and P2, P3 non-structural protein encoding regions.
  12. Walton C, Somboon P, O'Loughlin SM, Zhang S, Harbach RE, Linton YM, et al.
    Infect Genet Evol, 2007 Jan;7(1):93-102.
    PMID: 16782411
    The species diversity and genetic structure of mosquitoes belonging to the Anopheles maculatus group in Southeast Asia were investigated using the internal transcribed spacer 2 (ITS2) of ribosomal DNA (rDNA). A molecular phylogeny indicates the presence of at least one hitherto unrecognised species. Mosquitoes of chromosomal form K from eastern Thailand have a unique ITS2 sequence that is 3.7% divergent from the next most closely related taxon (An. sawadwongporni) in the group. In the context of negligible intraspecific variation at ITS2, this suggests that chromosomal form K is most probably a distinct species. Although An. maculatus sensu stricto from northern Thailand and southern Thailand/peninsular Malaysia differ from each other in chromosomal banding pattern and vectorial capacity, no intraspecific variation was observed in the ITS2 sequences of this species over this entire geographic area despite an extensive survey. A PCR-based identification method was developed to distinguish five species of the group (An. maculatus, An. dravidicus, An. pseudowillmori, An. sawadwongporni and chromosomal form K) to assist field-based studies in northwestern Thailand. Sequences from 187 mosquitoes (mostly An. maculatus and An. sawadwongporni) revealed no intraspecific variation in specimens from Thailand, Cambodia, mainland China, Malaysia, Taiwan and Vietnam, suggesting that this identification method will be widely applicable in Southeast Asia. The lack of detectable genetic structure also suggests that populations of these species are either connected by gene flow and/or share a recent common history.
  13. Zhang S, Singh B, Rodriguez DA, Chasnoits AR, Hussin A, Ching CK, et al.
    Europace, 2015 Nov;17(11):1720-6.
    PMID: 26037794 DOI: 10.1093/europace/euv103
    This study aims to demonstrate that primary prevention (PP) patients with one or more additional risk factors are at a similar risk of life-threatening ventricular arrhythmias when compared with secondary prevention (SP) patients, and would receive similar benefit from an implantable cardioverter defibrillator (ICD), or cardiac resynchronization therapy-defibrillator (CRT-D) implant. The study evaluates the benefits of therapy for high-risk patients in countries where defibrillation therapy for PP of SCA is underutilized.
  14. Xiao Y, Zhang S, Dai N, Fei G, Goh KL, Chun HJ, et al.
    Gut, 2020 02;69(2):224-230.
    PMID: 31409606 DOI: 10.1136/gutjnl-2019-318365
    OBJECTIVE: To establish the non-inferior efficacy of vonoprazan versus lansoprazole in the treatment of Asian patients with erosive oesophagitis (EO).

    DESIGN: In this phase III, double-blind, multicentre study, patients with endoscopically confirmed EO were randomised 1:1 to receive vonoprazan 20 mg or lansoprazole 30 mg, once daily for up to 8 weeks. The primary endpoint was EO healing rate at 8 weeks. The secondary endpoints were EO healing rates at 2 and 4 weeks. Safety endpoints included treatment-emergent adverse events (TEAEs).

    RESULTS: In the vonoprazan (n=238) and lansoprazole (n=230) arms, 8-week EO healing rates were 92.4% and 91.3%, respectively (difference 1.1% (95% CI -3.822% to 6.087%)). The respective 2-week EO healing rates were 75.0% and 67.8% (difference 7.2% (95% CI -1.054% to 15.371%)), and the respective 4-week EO healing rates were 85.3% and 83.5% (difference 1.8% (95% CI -4.763% to 8.395%)). In patients with baseline Los Angeles classification grade C/D, 2-week, 4-week and 8-week EO healing rates were higher with vonoprazan versus lansoprazole (2 weeks: 62.2% vs 51.5%, difference 10.6% (95% CI -5.708% to 27.002%); 4 weeks: 73.3% vs 67.2%, difference 6.2% (95% CI -8.884 to 21.223); and 8 weeks: 84.0% vs 80.6%, difference 3.4% (95% CI -9.187% to 15.993%)). Overall, EO healing rates appeared higher with vonoprazan versus lansoprazole. TEAE rates were 38.1% and 36.6% in the vonoprazan and lansoprazole group, respectively.

    CONCLUSION: Our findings demonstrate the non-inferior efficacy of vonoprazan versus lansoprazole in terms of EO healing rate at 8 weeks in this population. Safety outcomes were similar in the two treatment arms.

    TRIAL REGISTRATION NUMBER: NCT02388724.

  15. Sun Z, He G, Huang N, Chen H, Zhang S, Zhao Z, et al.
    Front Public Health, 2020;8:609974.
    PMID: 33344408 DOI: 10.3389/fpubh.2020.609974
    Background: COVID-19 developed into a global pandemic in 2020 and poses challenges regarding the prevention and control capabilities of countries. A large number of inbound travelers from other regions could lead to a renewed outbreak of COVID-19 in the local regions. Globally, as a result of the imbalance in the control of the epidemic, all countries are facing the risk of a renewed COVID-19 outbreak brought about by travelers from epidemic areas. Therefore, studies on a proper management of the inbound travelers are urgent. Methods: We collected a total of 4,733,414 inbound travelers and 174 COVID-19 diagnosed patients in Yunnan province from 21 January 2020 to 20 February 2020. Data on place of origin, travel history, age, and gender, as well as whether they had suspected clinical manifestations for inbound travelers in Yunnan were collected. The impact of inbound travelers on the local epidemic was analyzed with a collinear statistical analysis and the effect of the control measures on the epidemic was evaluated with a sophisticated modeling approach. Results: Of the 174 COVID-19 patients, 60.9% were not from Yunnan, and 76.4% had a history of travel in Hubei. The amount of new daily cases in Yunnan was significant correlated with the number of inbound travelers from Hubei and suspected cases among them. Using Susceptible-Exposed-Infectious-Recovered (SEIR) model analysis, we found that the prevention and control measures dropped the local R0 down to 1.07 in Yunnan province. Conclusions: Our preliminary analysis showed that the proper management of inbound travelers from outbreak areas has a significantly positive effect on the prevention and control of the virus. In the process of resettlement, some effective measures taken by Yunnan province may provide an important reference for preventing the renewed COVID-19 outbreak in other regions.
  16. Zhang S, Wang W, Sawhney JPS, Krittayaphong R, Kim HS, Nhan VT, et al.
    Int J Cardiol, 2020 07 01;310:16-22.
    PMID: 32192746 DOI: 10.1016/j.ijcard.2020.01.008
    BACKGROUND: Cardiovascular diseases account for approximately half of all deaths in Asia. The present analysis aimed to evaluate characteristics, antithrombotic management patterns (AMPs), and outcomes in patients with acute coronary syndrome (ACS) who underwent in-hospital percutaneous coronary intervention (PCI) and survived to hospital discharge, using data from the EPICOR Asia registry (NCT01361386).

    METHODS: Two-year post-discharge follow-up data were analyzed from 8757 ACS PCI patients from EPICOR Asia (218 centers, eight countries). Major adverse cardiovascular events (MACE; death, non-fatal myocardial infarction [MI], non-fatal ischemic stroke), PCI characteristics, and AMPs were recorded. For MACE, time - to - event was analyzed using Cox regression.

    RESULTS: Primary PCI was performed in 62.0% of ST-segment elevation MI (STEMI), 38.7% of non-STEMI (NSTEMI), and 24.2% of unstable angina (UA) patients. At 12 months, 88.1% of patients were on dual antiplatelet therapy (DAPT), with no differences by index event. Most (61.5%) still received DAPT at 2 years. Two-year incidences of mortality, composite MACE, and bleeding were 3.6%, 6.2%, and 6.6%, respectively. Risk of death and MACE was increased with STEMI and NSTEMI vs. UA. Patients from East Asia showed lower mortality and more bleeding vs. Southeast Asia/India.

    CONCLUSIONS: Many patients in EPICOR Asia underwent PCI and received DAPT up to 2 years post-discharge. These real-world findings improve our understanding of AMP impact on outcomes in Asian patients with ACS undergoing PCI.

  17. Duray GZ, Ritter P, El-Chami M, Narasimhan C, Omar R, Tolosana JM, et al.
    Heart Rhythm, 2017 05;14(5):702-709.
    PMID: 28192207 DOI: 10.1016/j.hrthm.2017.01.035
    BACKGROUND: Early performance of the Micra transcatheter pacemaker from the global clinical trial reported a 99.2% implant success rate, low and stable pacing capture thresholds, and a low (4.0%) rate of major complications up to 6 months.

    OBJECTIVE: The purpose of this report was to describe the prespecified long-term safety objective of Micra at 12 months and electrical performance through 24 months.

    METHODS: The Micra Transcatheter Pacing Study was a prospective single-arm study designed to assess the safety and efficacy of the Micra VVIR leadless/intracardiac pacemaker. Enrolled patients met class I or II guideline recommendations for de novo ventricular pacing. The long-term safety objective was freedom from a system- or procedure-related major complication at 12 months. A predefined historical control group of 2667 patients with transvenous pacemakers was used to compare major complication rates.

    RESULTS: The long-term safety objective was achieved with a freedom from major complication rate of 96.0% at 12 months (95% confidence interval 94.2%-97.2%; P < .0001 vs performance goal). The risk of major complications for patients with Micra (N = 726) was 48% lower than that for patients with transvenous systems through 12 months postimplant (hazard ratio 0.52; 95% confidence interval 0.35-0.77; P = .001). Across subgroups of age, sex, and comorbidities, Micra reduced the risk of major complications compared to transvenous systems. Electrical performance was excellent through 24 months, with a projected battery longevity of 12.1 years.

    CONCLUSION: Long-term performance of the Micra transcatheter pacemaker remains consistent with previously reported data. Few patients experienced major complications through 12 months of follow-up, and all patient subgroups benefited as compared to transvenous pacemaker historical control group.

  18. Singh B, Zhang S, Ching CK, Huang D, Liu YB, Rodriguez DA, et al.
    Pacing Clin Electrophysiol, 2018 12;41(12):1619-1626.
    PMID: 30320410 DOI: 10.1111/pace.13526
    BACKGROUND: Despite available evidence that implantable cardioverter defibrillators (ICDs) reduce all-cause mortality among patients at risk for sudden cardiac death, utilization of ICDs is low especially in developing countries.

    OBJECTIVE: To summarize reasons for ICD or cardiac resynchronization therapy defibrillator implant refusal by patients at risk for sudden cardiac arrest (Improve SCA) in developing countries.

    METHODS: Primary prevention (PP) and secondary prevention (SP) patients from countries where ICD use is low were enrolled. PP patients with additional risk factors (syncope, ejection fraction 

  19. Yip AK, Zhang S, Chong LH, Cheruba E, Woon JYX, Chua TX, et al.
    Front Cell Dev Biol, 2021;9:735298.
    PMID: 34869319 DOI: 10.3389/fcell.2021.735298
    Focal adhesions (FAs) are specialized structures that enable cells to sense their extracellular matrix rigidity and transmit these signals to the interior of the cells, bringing about actin cytoskeleton reorganization, FA maturation, and cell migration. It is known that cells migrate towards regions of higher substrate rigidity, a phenomenon known as durotaxis. However, the underlying molecular mechanism of durotaxis and how different proteins in the FA are involved remain unclear. Zyxin is a component of the FA that has been implicated in connecting the actin cytoskeleton to the FA. We have found that knocking down zyxin impaired NIH3T3 fibroblast's ability to sense and respond to changes in extracellular matrix in terms of their FA sizes, cell traction stress magnitudes and F-actin organization. Cell migration speed of zyxin knockdown fibroblasts was also independent of the underlying substrate rigidity, unlike wild type fibroblasts which migrated fastest at an intermediate substrate rigidity of 14 kPa. Wild type fibroblasts exhibited durotaxis by migrating toward regions of increasing substrate rigidity on polyacrylamide gels with substrate rigidity gradient, while zyxin knockdown fibroblasts did not exhibit durotaxis. Therefore, we propose zyxin as an essential protein that is required for rigidity sensing and durotaxis through modulating FA sizes, cell traction stress and F-actin organization.
  20. Lam CS, Anand I, Zhang S, Shimizu W, Narasimhan C, Park SW, et al.
    Eur J Heart Fail, 2013 Aug;15(8):928-36.
    PMID: 23568645 DOI: 10.1093/eurjhf/hft045
    Our aim is to determine mortality and morbidity in Asian patients under clinical management for heart failure (HF). Specifically, we will define the incidence of, and risk factors for, sudden cardiac death, as well as the socio-cultural factors influencing therapeutic choices in these patients. Methods This is a prospective observational multinational Asian registry of 5000 patients with symptomatic HF (stage C) and LV systolic dysfunction (EF ≤ 40%) involving 44 centres across 11 Asian regions (China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, Taiwan and Thailand). Data collection includes demographic variables, clinical symptoms, functional status, date of HF diagnosis and prior cardiovascular investigations, clinical risk factors, lifestyle factors, socio-economic status, and survey of cultural beliefs, health practices, and attitudes towards device therapy. Centre-level characteristics (case load, referral pattern, specialization, and infrastructure) are also obtained. Patients uniformly undergo standard 12-lead ECG and transthoracic echocardiography at baseline, and are followed over 3 years for outcomes of death or hospitalization. The mode of death and cause of hospitalization are adjudicated by a central event adjudication committee using pre-specified criteria. Perspective By providing prospective data regarding the demographics, risk factors, and outcomes of Asian patients under treatment for HF, the ASIAN-HF registry is expected to advance fundamental understanding of the burden and predictors of death and hospitalization among these patients. The knowledge gained will be important for guiding resource allocation and planning preventive strategies to address the unmet and growing clinical needs of patients with cardiovascular disease in Asia. Trial registration NCT01633398.
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