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The ability to control the expression of a therapeutic gene or a transgene in mammalian cells is crucial for safe and efficacious gene and cell therapy, as well as for elucidating the function of a specific gene product. Yet current mammalian gene regulation systems either evoke harmful immune responses in hosts or lack the required regulatory efficiency. Here we describe a highly responsive RNA-based molecular switch, the pA regulator, that harnesses the power of polyA signal cleavage within the 5’ UTR to control mammalian gene expression. The pA regulator is governed by a ‘dual mechanism’ to ensure maximal control of gene expression: (1) aptamer clamping of polyA signal via drug binding and (2) drug-induced alternative splicing that removes the polyA signal. The metholology achieves an induction efficiency up to 900-fold with an EC50of 0.5μg/ml Tetracycline, a drug concentration that falls well within the FDA-approved dose range. The pA regulator circumvents the immune responses that plague other systems by eliminating the use of a regulatory foreign protein and the need to change transgene coding sequences. Furthermore, it is not dependent on any specific promoter, therefore the system is simple to implement in a single non-viral or viral vector. In a mouse study using AAV-mediated gene transfer, we showed that the pA regulator controlled transgene expression in a “dose-dependent’ and “reversible” manner and exhibited long-term stabilityin vivo, in which both features are crucial for effective therapeutics. The pA regulator is the first non-immunogenic system that demonstrates an EC50at a drug concentration approved by FDA, making it a clinically relevant gene regulation system that could open a new window of opportunity in clinical applications as well as biological studies.

Influenza vaccine effectively reduced risks for in-hospital death or hospitalization, regardless of statin use., Debates on whether statin use reduces the effectiveness of influenza vaccines against critical illness and death among persons >65 years of age continue. We conducted a study of 9,427,392 persons >65 years of age who did and did not receive influenza vaccinations during 12 consecutive influenza seasons, 2000–01 through 2011–12. Using data from Taiwan’s National Health Insurance Research Database, we performed propensity score-matching to compare vaccinated persons with unvaccinated controls. After propensity score-matching, the vaccinated group had lower risks for in-hospital death from influenza and pneumonia and for hospitalization for pneumonia and influenza, circulatory conditions, and critical illnesses compared with the unvaccinated group. We stratified the 2 groups by statin use and analyzed data by interaction analysis and saw no statistically significant difference. We found that influenza vaccine effectively reduced risks for hospitalization and death in persons >65 years of age, regardless of statin use.

Objective The objective of this study is to determine whether vaccination against influenza is associated with a reduced risk of acute kidney injury (AKI) in a nationwide cohort of adults aged ≥65 years. Methods We investigated a total of 13,270 patients aged ≥65 years who were hospitalized for AKI between 2000 and 2013 from Taiwan's National Health Insurance Research Database. Each AKI case was matched with one control subject according to duration of follow-up, age, sex, monthly income, urbanization level, and baseline comorbidities. Odds ratios (ORs) for AKI associated with exposure to the influenza vaccine in the previous year were calculated in a nested case-control analysis. Results Influenza vaccination in the previous year was associated with a lower risk of AKI (adjusted OR 0.67, 95% confidence interval [CI] 0.63–0.72). Compared with a reference group of unvaccinated individuals with no influenza infection, vaccination with no influenza infection was associated with a lower risk of AKI (adjusted OR 0.68, 95% CI 0.64–0.73). Lack of vaccination and presence of influenza infection was associated with a higher risk of AKI (adjusted OR 1.78, 95% CI 1.57–2.01), whereas the risk of AKI was insignificant in vaccinated patients who developed influenza (adjusted OR 1.01, 95% CI 0.69–1.18). Conclusions The risk of AKI was 37% lower among older people who received vaccination against influenza in a real-world setting. Further work is required to clarify causality.

ObjectivesAnimal and ex vitro studies suggested lipid-lowering agents (LLAs) may be used as an adjunct to standard anti- tuberculosis (TB) treatment. No human study has been conducted to date. Using the Taiwan National Health Insurance Research Database (NHIRD), the current population-based cohort study sought to examine the association between use of LLAs and outcomes of patients with pulmonary TB receiving anti-TB treatment.MethodsUsing a NHIRD from 2003 to 2010, this population-based cohort study retrospectively examined the association between LLAs (statins or fibrates) and the outcomes of patients with pulmonary TB receiving anti-TB treatment.ResultsA total of 1452 adult patients newly diagnosed with pulmonary TB during the study period were identified and compared with 5808 matched patients. In the LAA cohort, 1258 received statin, and 295 received fibrate. Compared with patients who did not take LLA, patients who took oral LLAs had similar incidence of treatment completion at 9, 12, and 24 months.ConclusionsNeither statins nor fibrates provide clinical benefit superior to that achieved with standard anti-tuberculosis treatment. Future clinical trials should investigate the effects of statins and fibrates on short-course standard anti-TB therapy.

Rationale: Patients with sepsis who survive to hospital discharge may present with ongoing high morbidity and mortality. However, little is known about the risk of long-term, all-cause mortality and cardiovascular outcomes after sepsis.Objectives: Our study aimed to investigate the long-term clinical outcomes in sepsis survivors.Methods: In this nationwide population-based study, data from patients with sepsis were retrieved from Taiwan’s National Health Insurance Research Database between 2000 and 2002. Each sepsis survivor was 1:1 propensity-matched to control subjects from two different control populations: subjects who were in the general population and subjects who were hospitalized for a nonsepsis diagnosis. The primary outcomes were all-cause mortality, major adverse cardiovascular events, myocardial infarction, heart failure, stroke, and sudden cardiac death or ventricular arrhythmia.Measurements and Main Results: Compared with matched population control subjects, sepsis survivors had higher risks...

To evaluate the long-term survival rate of critically ill sepsis survivors following cardiopulmonary resuscitation on a national scale.Retrospective and observational cohort study.Data were extracted from Taiwan's National Health Insurance Research Database.A total of 272,897 ICU patients with sepsis were identified during 2000-2010. Patients who survived to hospital discharge were enrolled. Post-discharge survival outcomes of ICU sepsis survivors who received cardiopulmonary resuscitation were compared with those of patients who did not experience cardiopulmonary arrest using propensity score matching with a 1:1 ratio.None.Only 7% (n = 3,207) of sepsis patients who received cardiopulmonary resuscitation survived to discharge. The overall 1-, 2-, and 5-year postdischarge survival rates following cardiopulmonary resuscitation were 28%, 23%, and 14%, respectively. Compared with sepsis survivors without cardiopulmonary arrest, sepsis survivors who received cardiopulmonary resuscitation had a greater risk of all-cause mortality after discharge (hazard ratio, 1.38; 95% CI, 1.34-1.46). This difference in mortality risk diminished after 2 years (hazard ratio, 1.11; 95% CI, 0.96-1.28). Multivariable analysis showed that independent risk factors for long-term mortality following cardiopulmonary resuscitation were male sex, older age, receipt of care in a nonmedical center, higher Charlson Comorbidity Index score, chronic kidney disease, cancer, respiratory infection, vasoactive agent use, and receipt of renal replacement therapy during ICU stay.The long-term outcome was worse in ICU survivors of sepsis who received in-hospital cardiopulmonary resuscitation than in those who did not, but this increased risk of mortality diminished at 2 years after discharge.

Renin-angiotensin-aldosterone system blockers are the preferred antihypertensive medications in patients with diabetes and prior stroke. This study aimed to compare the effects of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) in terms of major adverse cardiac events (MACEs) in patients with diabetes who survived ischemic stroke.We conducted an observational, nationwide, propensity score-matched cohort study using Taiwan's National Health Insurance Research Database. Patients aged at least 20 years with type 2 diabetes who initiated ACEI (n = 15,959) or ARB (n = 23,929) use within 90 days after discharge for first ischemic stroke between January 2000 and December 2011 were allocated to ACEI and ARB groups, respectively. The primary outcomes were MACEs (myocardial infarction, ischemic stroke, and cardiovascular mortality). The secondary outcomes were hospitalization for acute kidney injury and hyperkalemia. Intention-to-treat and as-treated models were used.Intention-to-treat analysis showed no significant difference between the ACEI and ARB groups in the outcomes of MACEs [hazard ratio (HR), 0.99; 95% confidence interval (CI), 0.95-1.04], including ischemic stroke (HR, 1.01; 95% CI, 0.97-1.06), myocardial infarction (HR, 1.06; 95% CI, 0.95-1.18), and cardiovascular mortality (HR, 0.98; 95% CI, 0.91-1.06). As-treated analysis produced similar results. Additionally, the groups showed no difference in the risk of hospitalization for acute kidney injury or hyperkalemia.Our study supports the hypothesis that the risks of MACEs and two additional secondary outcomes in patients with diabetes who survived ischemic stroke did not differ according to ACEI versus ARB use.

Background— Whether oral anticoagulant use should be considered in patients undergoing hemodialysis with atrial fibrillation (AF) remains controversial because of the uncertainty regarding risk-benefit assessments. The purpose of this study was to investigate the risk of ischemic stroke in patients undergoing hemodialysis with new-onset AF, in comparison with those without arrhythmia. Methods and Results— This nationwide, population-based, propensity score–matched cohort study used data from Taiwan’s National Health Insurance Research Database during 1998 to 2011 for patients on hemodialysis with new-onset nonvalvular AF and matched subjects without arrhythmia. The clinical end points were ischemic stroke (fatal or nonfatal), all-cause death, and other serious adverse cardiovascular events. In comparison with the matched cohort, patients with AF (n=6772) had higher risks of ischemic stroke (adjusted hazard ratio [aHR], 1.27; 95% confidence interval [CI], 1.13–1.43), all-cause death (aHR, 1.59; 95% CI, 1.52–1.67), in-hospital cardiovascular death (aHR, 1.83; 95% CI, 1.71–1.94), myocardial infarction (aHR, 1.33; 95% CI, 1.17–1.51), and hospitalization for heart failure (aHR, 1.90; 95% CI, 1.76–2.05). After considering in-hospital death as a competing risk, AF significantly increased the risk of heart failure (HR, 1.56; 95% CI, 1.45–1.68), but not those of ischemic stroke and myocardial infarction. Additionally, the predictive value of the CHA 2 DS 2 –VASc score for ischemic stroke was diminished in the competing-risk model. Conclusions— The risk of stroke was only modestly higher in patients undergoing hemodialysis with new-onset AF than in those without AF, and it became insignificant when accounting for the competing risk of in-hospital death.

In a large observational database study of add-on treatments to metformin, the addition of dipeptidyl peptidase-4 (DPP-4) inhibitors was associated with a lower risk for all-cause mortality, stroke...

Background— Substantial infective endocarditis (IE)–related morbidity and mortality may occur even after successful treatment. However, no previous study has explored long-term hard end points (ie, stroke, myocardial infarction, heart failure, cardiovascular death) in addition to all-cause mortality in IE survivors. Methods and Results— A nationwide population-based cohort study was conducted among IE survivors identified with the use of the Taiwan National Health Insurance Research Database during 2000 to 2009. IE survivors were defined as those who survived after discharge from first hospitalization with a diagnosis of IE. A total of 10 116 IE survivors were identified. IE survivors were matched to control subjects without IE at a 1:1 ratio through the use of propensity scores. The primary outcomes were stroke, myocardial infarction, readmission for heart failure, and sudden cardiac death or ventricular arrhythmia. The secondary outcomes were repeat IE and all-cause mortality. Compared with the matched cohort, IE survivors had higher risks of ischemic stroke (adjusted hazard ratio [aHR], 1.59; 95% confidence interval [CI], 1.40–1.80), hemorrhagic stroke (aHR, 2.37; 95% CI, 1.90–2.96), myocardial infarction (aHR, 1.44; 95% CI, 1.17–1.79), readmission for heart failure (aHR, 2.24; 95% CI, 2.05–2.43), sudden death or ventricular arrhythmia (aHR, 1.69; 95% CI, 1.44–1.98), and all-cause death (aHR, 2.27; 95% CI, 2.14–2.40). Risk factors for repeat IE were older age, male sex, drug abuse, and valvular replacement after an initial episode of IE. Conclusion— Despite treatment, the risk of long-term major adverse cardiac events was substantially increased in IE survivors.

Background and objectives We aimed to investigate the benefits and risks of dual antiplatelet therapy (DAPT) after coronary drug-eluting stent (DES) implantation in patients undergoing hemodialysis. Design, setting, participants, & measurements A nested case-control analysis of patients on hemodialysis after receipt of DES and DAPT treatment was conducted using data from Taiwan’s National Health Insurance Research Database for the period 2007–2011. Cases of myocardial infarction or death within 1 year after DES implantation were matched one-to-one with control patients. Odds ratios were calculated to compare DAPT continuation with discontinuation. Additionally, a propensity score–adjusted 6-month landmark cohort analysis was also conducted to evaluate the long-term benefits and risks of prolonged (>6 months) compared with ≤6 months of DAPT use. The primary outcomes were death and myocardial infarction. The secondary outcomes were ischemic stroke, revascularization, and major bleeding. Results In the nested case-control analysis, patients who continued DAPT had a lower rate of death or myocardial infarction within 1 year after receipt of a DES (adjusted odds ratio, 0.54; 95% confidence interval, 0.36 to 0.81; P =0.003), whereas this association became statistically nonsignificant when compared with patients who discontinued DAPT for the period between 6 and 12 months after receipt of a DES (adjusted odds ratio, 1.51; 95% confidence interval, 0.75 to 3.04). In the propensity score–adjusted cohort analysis, >6 months of DAPT use was not associated with different primary or secondary outcomes than shorter-term use. Conclusions Our findings support that the clinical effectiveness of extended DAPT in a hemodialysis population may be tempered after 6 months post-DES implantation.

Objectives Intravenous patient-controlled analgesia (IVPCA) is often used to relieve pain after colorectal surgery. This study aimed to model the trajectory of analgesic demand over time after colorectal cancer surgery and explore potentially relevant influential factors using latent curve analysis, focusing on laparoscopic-assisted surgery and renal function. Materials and methods Patients receiving colorectal surgery with postoperative IVPCA were randomly divided into 2 equal parts to enable model construction and cross validation. Archived data were retrieved from the IVPCA pump. Latent curve modeling with 2 latent variables that reflected the baseline and slope of IVPCA demand trajectory over time was used and the effects of potentially influential factors on the 2 latent variables were evaluated. Goodness-of-fit indices were used to assess the model fit to both the model construction and validation data sets. Results Data were collected from 834 patients, of whom 112 had laparoscopic-assisted surgery. Latent curve analysis revealed that body weight increased the baseline analgesic demand over time, whereas increasing age, female sex, poor renal function, and laparoscopic-assisted surgery decrease it. By contrast, only age and weight exerted significant effects on the slope parameter to modify the trajectory of IVPCA demand. Patients with higher age or less weight tended to have a smoother decreasing trajectory of analgesic demands over time. There was good cross validation, as the parameter estimates derived from the model construction data set fitted well to the validation data set (root mean square error of approximation: 0.05). Conclusion Laparoscopic-assisted surgery and renal function affected the baseline trajectory of IVPCA demand over time, but had no significant effect on its shape.

Although oral antidiabetic drugs (OADs) have been associated with immunomodulation in preclinical studies, little is still known about the association between the use of OADs and the risk of sepsis. Using a cohort of patients, extracted from Taiwan’s National Health Insurance Research Database, with type 2 diabetes who were newly diagnosed between 2010 and 2012 and treated with OADs, we conducted a nested case-control study involving 43,015 cases (patients who were first hospitalized for sepsis) and 43,015 matched controls. Compared with non-use, metformin use was associated with a decreased risk of developing sepsis (adjusted odds ratio [OR] 0.80, 95% confidence interval [CI] 0.77–0.83, P P

High-grade serous ovarian cancer (HGSC) is among the most lethal forms of cancer in women. Excessive genomic rearrangements, which are expected to create fusion oncogenes, are the hallmark of this cancer. Here we report a cancer-specific gene fusion between BCAM, a membrane adhesion molecule, and AKT2, a key kinase in the PI3K signaling pathway. This fusion is present in 7% of the 60 patient cancers tested, a significant frequency considering the highly heterogeneous nature of this malignancy. Further, we provide direct evidence that BCAM-AKT2 is translated into an in-frame fusion protein in the patient's tumor. The resulting AKT2 fusion kinase is membrane-associated, constitutively phosphorylated, and activated as a functional kinase in cells. Unlike endogenous AKT2, whose activity is tightly regulated by external stimuli, BCAM-AKT2 escapes the regulation from external stimuli. Moreover, a BCAM-AKT2 fusion gene generated via chromosomal translocation using the CRISPR/Cas9 system leads to focus formation in both OVCAR8 and HEK-293T cell lines, suggesting that BCAM-AKT2 is oncogenic. Together, the results indicate that BCAM-AKT2 expression is a new mechanism of AKT2 kinase activation in HGSC. BCAM-AKT2 is the only fusion gene in HGSC that is proven to translate an aberrant yet functional kinase fusion protein with oncogenic properties. This recurrent genomic alteration is a potential therapeutic target and marker of a clinically relevant subtype for tailored therapy of HGSC.

Synthetic Biology is an interdisciplinary approach combining biotechnology, evolutionary biology, molecular biology, systems biology and biophysics. While the exact definition of Synthetic Biology might still be debatable, its focus on design and construction of biological devices that perform useful functions is clear and of great utility to engineering algae. This relies on the re-engineering of biological circuits and optimization of certain metabolic pathways to reprogram algae and introduce new functions in them via the use of genetic modules. Genetic editing tools are primary enabling techniques in Synthetic Biology and this chapter discusses common techniques that show promise for algal gene editing. The genetic editing tools discussed in this chapter include RNA interference (RNAi) and artificial microRNAs, RNA scaffolds, transcription activator-like effector nucleases (TALENs), RNA guided Cas9 endonucleases (CRISPR), and multiplex automated genome engineering (MAGE). DNA and whole genome synthesis is another enabling technology in Synthetic Biology and might present an alternative approach to drastically and readily modify algae. Clear and powerful examples of the potential of whole genome synthesis for algal engineering are presented. Also, the development of relevant computational tools, and genetic part registries has stimulated further advancements in the field and their utility in algal research and engineering is described. For now, the majority of synthetic biology efforts are focused on microbes as many pressing problems, such as sustainability in food and energy production rely on modification of microorganisms. Synthetic modifications of algal strains to enhance desired physiological properties could lead to improvements in their utility.

High-grade serous ovarian cancer (HGSC) is among the most lethal forms of cancer in women. Excessive genomic rearrangements, which are expected to create fusion oncogenes, are the hallmark of this cancer. Using high-throughput RNAseq, we identify a cancer-specific gene fusion between BCAM, a membrane adhesion molecule, and AKT2, a key kinase in the PI3K signaling pathway. This fusion is present in 7% of the 60 patient cancers tested, a significant frequency considering the highly heterogeneous nature of this malignancy. Further, we provide direct evidence that BCAM-AKT2 is translated into an in-frame fusion protein in the patient's tumor. The resulting AKT2 fusion kinase is membrane-associated, constitutively phosphorylated, and activated as a functional kinase in cells. Unlike endogenous AKT2, whose activity is tightly regulated by external stimuli, BCAM-AKT2 escapes the regulation from external stimuli. Moreover, a BCAM-AKT2 fusion gene generated via chromosomal translocation using the CRISPR/Cas9 system leads to focus formation in both OVCAR8 and HEK-293T cell lines, suggesting that BCAM-AKT2 is oncogenic. Together, the results indicate that BCAM-AKT2 expression is a new mechanism of AKT2 kinase activation in HGSC. BCAM-AKT2 is the only fusion gene in HGSC that is proven to translate an aberrant yet functional kinase fusion protein with oncogenic properties. This recurrent genomic alteration is a potential therapeutic target and marker of a clinically relevant subtype for tailored therapy of HGSC. Citation Format: Kalpana Kannan, Cristian Coarfa, Pei-Wen Chao, Liming Luo, Yan Wang, Amy E. Brinegar, Shannon M. Hawkins, Aleksandar Milosavljevic, Martin M. Matzuk, and Laising Yen. A RECURRENT BCAM-AKT2 FUSION GENE LEADS TO A CONSTITUTIVELY ACTIVATED AKT2 FUSION KINASE IN HIGH-GRADE SEROUS OVARIAN CARCINOMA [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr MIP-076.

Intensive care unit (ICU)-acquired weakness is a common issue for sepsis survivors that is characterized by impaired muscle strength and causes functional disability. Although inpatient rehabilitation has not been found to reduce in-hospital mortality, the impact of postdischarge rehabilitation on sepsis survivors is uncertain.To investigate the benefit of postdischarge rehabilitation to long-term mortality in sepsis survivors.We conducted a nationwide, population-based, high-dimensional propensity score-matched cohort study using Taiwan's National Health Insurance Research Database. The rehabilitation cohort comprised 15,535 ICU patients who survived sepsis and received rehabilitation within 3 months after discharge between 2000 and 2010. The control cohort consisted of 15,535 high-dimensional propensity score-matched subjects who did not receive rehabilitation within 3 months after discharge. The endpoint was mortality during the 10-year follow-up period.Compared with the control cohort, the rehabilitation cohort had a significantly lower risk of 10-year mortality (adjusted hazard ratio, 0.94; 95% confidence interval, 0.92-0.97; P0.001), with an absolute risk reduction of 1.4 per 100 person-years. The frequency of rehabilitation was inversely associated with 10-year mortality (≥3 vs. 1 course: adjusted hazard ratio, 0.82; P0.001). Compared with the control cohort, improved survival was observed in the rehabilitation cohort among ill patients who had more comorbidities, required more prolonged mechanical ventilation, and had longer ICU or hospital stays, but not among those with the opposite conditions (i.e., less ill patients).Postdischarge rehabilitation may be associated with a reduced risk of 10-year mortality in the subset of patients with particularly long ICU courses.

Renin and aldosterone activity levels are low in elderly patients, raising concerns about the benefits and risks of angiotensin-converting-enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARB) use. However, data from direct comparisons of the effects of ACEIs on ARBs in the elderly population remain inconclusive. In this nationwide study, all patients aged ≥ 70 years were retrieved from the Taiwan National Health Insurance database for the period 2000 to 2009 and were followed up until the end of 2010. The ARB cohort (12,347 patients who continuously used ARBs for ≥ 90 days) was matched to ACEI cohort using high-dimensional propensity score (hdPS). Intention-to-treat (ITT) and as-treated (AT) analyses were conducted. In the ITT analysis, after considering death as a competing risk, the ACEI cohort had similar risks of myocardial infarction (hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.79–1.06), ischemic stroke (HR 0.98, 95% CI 0.90–1.07), and heart failure (HR 0.93, 95% CI 0.83–1.04) compared with the ARB cohort. No difference in adverse effects, such as acute kidney injury (HR 0.99, 95% CI 0.89–1.09) and hyperkalemia (HR 1.02, 95% CI 0.87–1.20), was observed between cohorts. AT analysis produced similar results to those of ITT analysis. We were unable to demonstrate a survival difference between cohorts (HR 1.03, 95% CI 0.88–1.21) after considering drug discontinuation as a competing risk in AT analysis. Our study supports the notion that ACEI and ARB users have similar risks of major adverse cardiovascular events (MACE), even in elderly populations.