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Observation of high-energy neutrinos from the Galactic plane. Science 2023; 380:1338-1343. [PMID: 37384687 DOI: 10.1126/science.adc9818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 05/04/2023] [Indexed: 07/01/2023]
Abstract
The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.
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Case Report: Successful Treatment of a Child With COVID-19 Reinfection-Induced Fulminant Myocarditis by Cytokine-Adsorbing oXiris® Hemofilter Continuous Veno-Venous Hemofiltration and Extracorporeal Membrane Oxygenation. Front Pediatr 2022; 10:946547. [PMID: 35903158 PMCID: PMC9315247 DOI: 10.3389/fped.2022.946547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/15/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Indirect cardiomyocyte damage-related hyperinflammatory response is one of the key mechanisms in COVID-19-induced fulminant myocarditis. In addition to the clinical benefit of using cytokines absorption hemofiltration, the effectiveness of instituting veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support for cardiac compromise has been reported. However, current literature enunciates a paucity of available data on the effectiveness of these novel modalities. CASE PRESENTATION We reported a 9-year-old boy with recurrent COVID-19 infection-causing fulminant myocarditis, who was treated successfully by using novel modalities of oXiris ® hemofilter continuous venovenous hemofiltration (CVVH) and VA-ECMO. The patient made a full recovery without any sequelae. CONCLUSION We conclude that the novel highly-absorptive hemofilter CVVH and VA-ECMO may be effective treatment modalities in managing SARS-CoV-2-induced fulminant myocarditis. Our report highlights the need for further well-designed investigations to confirm this extrapolation.
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Associations of Underlying Health Conditions With Anxiety and Depression Among Outpatients: Modification Effects of Suspected COVID-19 Symptoms, Health-Related and Preventive Behaviors. Int J Public Health 2021; 66:634904. [PMID: 34335139 PMCID: PMC8284590 DOI: 10.3389/ijph.2021.634904] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 05/28/2021] [Indexed: 12/18/2022] Open
Abstract
Objectives: We explored the association of underlying health conditions (UHC) with depression and anxiety, and examined the modification effects of suspected COVID-19 symptoms (S-COVID-19-S), health-related behaviors (HB), and preventive behaviors (PB). Methods: A cross-sectional study was conducted on 8,291 outpatients aged 18–85 years, in 18 hospitals and health centers across Vietnam from 14th February to May 31, 2020. We collected the data regarding participant's characteristics, UHC, HB, PB, depression, and anxiety. Results: People with UHC had higher odds of depression (OR = 2.11; p < 0.001) and anxiety (OR = 2.86; p < 0.001) than those without UHC. The odds of depression and anxiety were significantly higher for those with UHC and S-COVID-19-S (p < 0.001); and were significantly lower for those had UHC and interacted with “unchanged/more” physical activity (p < 0.001), or “unchanged/more” drinking (p < 0.001 for only anxiety), or “unchanged/healthier” eating (p < 0.001), and high PB score (p < 0.001), as compared to those without UHC and without S-COVID-19-S, “never/stopped/less” physical activity, drinking, “less healthy” eating, and low PB score, respectively. Conclusion: S-COVID-19-S worsen psychological health in patients with UHC. Physical activity, drinking, healthier eating, and high PB score were protective factors.
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Appropriate Antibiotic Use and Associated Factors in Vietnamese Outpatients. Healthcare (Basel) 2021; 9:healthcare9060693. [PMID: 34201175 PMCID: PMC8228789 DOI: 10.3390/healthcare9060693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 06/04/2021] [Accepted: 06/06/2021] [Indexed: 01/21/2023] Open
Abstract
Background: Inappropriate antibiotic use among outpatients is recognized as the primary driver of antibiotic resistance. A proper understanding of appropriate antibiotic usage and associated factors helps to determine and limit inappropriateness. We aimed to identify the rate of appropriate use of antibiotics and identify factors associated with the inappropriate prescriptions. Methods: We conducted a cross-sectional descriptive study in outpatient antibiotic use at a hospital in Can Tho City, Vietnam, from August 1, 2019, to January 31, 2020. Data were extracted from all outpatient prescriptions at the Medical Examination Department and analyzed by SPSS 18 and Chi-squared tests, with 95% confidence intervals. The rationale for antibiotic use was evaluated through antibiotic selection, dose, dosing frequency, dosing time, interactions between antibiotics and other drugs, and general appropriate usage. Results: A total of 420 prescriptions were 51.7% for females, 61.7% with health insurance, and 44.0% for patients with one comorbid condition. The general appropriate antibiotic usage rate was 86.7%. Prescriptions showed that 11.0% and 9.5% had a higher dosing frequency and dose than recommended, respectively; 10.2% had an inappropriate dosing time; 3.1% had drug interactions; and only 1.7% had been prescribed inappropriate antibiotics. The risk of inappropriate antibiotic use increased in patients with comorbidities and antibiotic treatment lasting >7 days (p < 0.05). Conclusions: The study indicated a need for more consideration when prescribing antibiotics to patients with comorbidities or using more than 7 days of treatment.
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Impacts and interactions of COVID-19 response involvement, health-related behaviours, health literacy on anxiety, depression and health-related quality of life among healthcare workers: a cross-sectional study. BMJ Open 2020; 10:e041394. [PMID: 33293320 PMCID: PMC7722826 DOI: 10.1136/bmjopen-2020-041394] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES We examined impacts and interactions of COVID-19 response involvement, health-related behaviours and health literacy (HL) on anxiety, depression, and health-related quality of life (HRQoL) among healthcare workers (HCWs). DESIGN A cross-sectional study was conducted. Data were collected 6 April to 19 April 2020 using online-based, self-administered questionnaires. SETTING 19 hospitals and health centres in Vietnam. PARTICIPANTS 7 124 HCWs aged 21-60 years. RESULTS The COVID-19 response-involved HCWs had higher anxiety likelihood (OR (95% CI)=4.41 (3.53 to 5.51)), higher depression likelihood (OR(95% CI)=3.31 (2.71 to 4.05)) and lower HRQoL score (coefficient, b(95% CI)=-2.14 (-2.89 to -1.38)), compared with uninvolved HCWs. Overall, HCWs who smoked or drank at unchanged/increased levels had higher likelihood of anxiety, depression and lower HRQoL scores; those with unchanged/healthier eating, unchanged/more physical activity and higher HL scores had lower likelihood of anxiety, depression and higher HRQoL scores. In comparison to uninvolved HCWs who smoked or drank at never/stopped/reduced levels, involved HCWs with unchanged/increased smoking or drinking had lower anxiety likelihood (OR(95% CI)=0.34 (0.14 to 0.83)) or (OR(95% CI)=0.26 (0.11 to 0.60)), and lower depression likelihood (OR(95% CI)=0.33 (0.15 to 0.74)) or (OR(95% CI)=0.24 (0.11 to 0.53)), respectively. In comparison with uninvolved HCWs who exercised at never/stopped/reduced levels, or with those in the lowest HL quartile, involved HCWs with unchanged/increased exercise or with one-quartile HL increment reported lower anxiety likelihood (OR(95% CI)=0.50 (0.31 to 0.81)) or (OR(95% CI)=0.57 (0.45 to 0.71)), lower depression likelihood (OR(95% CI)=0.40 (0.27 to 0.61)) or (OR(95% CI)=0.63 (0.52 to 0.76)), and higher HRQoL scores (b(95% CI)=2.08 (0.58 to 3.58)), or (b(95% CI)=1.10 (0.42 to 1.78)), respectively. CONCLUSIONS Physical activity and higher HL were found to protect against anxiety and depression and were associated with higher HRQoL. Unexpectedly, smoking and drinking were also found to be coping behaviours. It is important to have strategic approaches that protect HCWs' mental health and HRQoL.
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Healthy Dietary Intake Behavior Potentially Modifies the Negative Effect of COVID-19 Lockdown on Depression: A Hospital and Health Center Survey. Front Nutr 2020; 7:581043. [PMID: 33304917 PMCID: PMC7701254 DOI: 10.3389/fnut.2020.581043] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/08/2020] [Indexed: 12/13/2022] Open
Abstract
Background: The COVID-19 pandemic causes a huge burden for affected countries. Several public health interventions were applied to contain the infection. However, the pandemic itself and the lockdown measure negatively influence people's lifestyles and psychological health. Purpose: To explore determinants of healthy dietary intake and depression, and examine the interaction between healthy dietary intake and COVID-19 lockdown on depression. Methods: A cross-sectional study was conducted at 18 hospitals and health centers from February 14 to May 31, 2020. Data of 8,291 outpatients were collected including patients' characteristics, clinical parameters, health literacy, healthy dietary intake (using the healthy eating score, HES), other health-related behaviors, and depression (using the patient health questionnaire, PHQ). Depression was defined as PHQ score ≥ 10. Results: Protective factors of healthy dietary intake and depression were higher education, better medication payment ability, higher social status, more physical activity, and higher health literacy, whereas older age, ever married, own business or other types of occupation, lockdown, suspected COVID-19 symptoms, and comorbidity were associated with lower HES scores and a higher depression likelihood. Besides, overweight/obesity and alcohol drinking were associated with lower HES scores. As compared with patients not under lockdown and with lowest HES score, those who were under lockdown and with lowest HES score had 10.6 times higher depression likelihood (odds ratio, OR, 10.60; 95% CI 6.88, 16.32; p < 0.001), whereas people with higher HES score had 15% lower depression likelihood (OR 0.85; 95% CI 0.82, 0.89; p < 0.001). Conclusions: Healthy dietary intake and depression were determined by several sociodemographic, clinical, and behavioral factors. Lockdown measure affects people's dietary intake behavior and depression. Importantly, healthy dietary intake potentially modifies the negative effect of lockdown on depression.
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Health Literacy, eHealth Literacy, Adherence to Infection Prevention and Control Procedures, Lifestyle Changes, and Suspected COVID-19 Symptoms Among Health Care Workers During Lockdown: Online Survey. J Med Internet Res 2020; 22:e22894. [PMID: 33122164 PMCID: PMC7674138 DOI: 10.2196/22894] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/25/2020] [Accepted: 10/28/2020] [Indexed: 01/16/2023] Open
Abstract
Background The COVID-19 pandemic has imposed a heavy burden on health care systems and governments. Health literacy (HL) and eHealth literacy (as measured by the eHealth Literacy Scale [eHEALS]) are recognized as strategic public health elements but they have been underestimated during the pandemic. HL, eHEALS score, practices, lifestyles, and the health status of health care workers (HCWs) play crucial roles in containing the COVID-19 pandemic. Objective The aim of this study is to evaluate the psychometric properties of the eHEALS and examine associations of HL and eHEALS scores with adherence to infection prevention and control (IPC) procedures, lifestyle changes, and suspected COVID-19 symptoms among HCWs during lockdown. Methods We conducted an online survey of 5209 HCWs from 15 hospitals and health centers across Vietnam from April 6 to April 19, 2020. Participants answered questions related to sociodemographics, HL, eHEALS, adherence to IPC procedures, behavior changes in eating, smoking, drinking, and physical activity, and suspected COVID-19 symptoms. Principal component analysis, correlation analysis, and bivariate and multivariate linear and logistic regression models were used to validate the eHEALS and examine associations. Results The eHEALS had a satisfactory construct validity with 8 items highly loaded on one component, with factor loadings ranked from 0.78 to 0.92 explaining 76.34% of variance; satisfactory criterion validity as correlated with HL (ρ=0.42); satisfactory convergent validity with high item-scale correlations (ρ=0.80-0.84); and high internal consistency (Cronbach α=.95). HL and eHEALS scores were significantly higher in men (unstandardized coefficient [B]=1.01, 95% CI 0.57-1.45, P<.001; B=0.72, 95% CI 0.43-1.00, P<.001), those with a better ability to pay for medication (B=1.65, 95% CI 1.25-2.05, P<.001; B=0.60, 95% CI 0.34-0.86, P<.001), doctors (B=1.29, 95% CI 0.73-1.84, P<.001; B 0.56, 95% CI 0.20-0.93, P=.003), and those with epidemic containment experience (B=1.96, 95% CI 1.56-2.37, P<.001; B=0.64, 95% CI 0.38-0.91, P<.001), as compared to their counterparts, respectively. HCWs with higher HL or eHEALS scores had better adherence to IPC procedures (B=0.13, 95% CI 0.10-0.15, P<.001; B=0.22, 95% CI 0.19-0.26, P<.001), had a higher likelihood of healthy eating (odds ratio [OR] 1.04, 95% CI 1.01-1.06, P=.001; OR 1.04, 95% CI 1.02-1.07, P=.002), were more physically active (OR 1.03, 95% CI 1.02-1.03, P<.001; OR 1.04, 95% CI 1.03-1.05, P<.001), and had a lower likelihood of suspected COVID-19 symptoms (OR 0.97, 95% CI 0.96-0.98, P<.001; OR 0.96, 95% CI 0.95-0.98, P<.001), respectively. Conclusions The eHEALS is a valid and reliable survey tool. Gender, ability to pay for medication, profession, and epidemic containment experience were independent predictors of HL and eHEALS scores. HCWs with higher HL or eHEALS scores had better adherence to IPC procedures, healthier lifestyles, and a lower likelihood of suspected COVID-19 symptoms. Efforts to improve HCWs’ HL and eHEALS scores can help to contain the COVID-19 pandemic and minimize its consequences.
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Aerosolisation during tracheal intubation and extubation in an operating theatre setting. Anaesthesia 2020; 76:182-188. [PMID: 33047327 PMCID: PMC7675280 DOI: 10.1111/anae.15301] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2020] [Indexed: 01/25/2023]
Abstract
Aerosol‐generating procedures such as tracheal intubation and extubation pose a potential risk to healthcare workers because of the possibility of airborne transmission of infection. Detailed characterisation of aerosol quantities, particle size and generating activities has been undertaken in a number of simulations but not in actual clinical practice. The aim of this study was to determine whether the processes of facemask ventilation, tracheal intubation and extubation generate aerosols in clinical practice, and to characterise any aerosols produced. In this observational study, patients scheduled to undergo elective endonasal pituitary surgery without symptoms of COVID‐19 were recruited. Airway management including tracheal intubation and extubation was performed in a standard positive pressure operating room with aerosols detected using laser‐based particle image velocimetry to detect larger particles, and spectrometry with continuous air sampling to detect smaller particles. A total of 482,960 data points were assessed for complete procedures in three patients. Facemask ventilation, tracheal tube insertion and cuff inflation generated small particles 30–300 times above background noise that remained suspended in airflows and spread from the patient’s facial region throughout the confines of the operating theatre. Safe clinical practice of these procedures should reflect these particle profiles. This adds to data that inform decisions regarding the appropriate precautions to take in a real‐world setting.
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eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory. PHYSICAL REVIEW LETTERS 2020; 125:141801. [PMID: 33064514 DOI: 10.1103/physrevlett.125.141801] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100 eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5 eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.
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The first infant case of COVID-19 acquired from a secondary transmission in Vietnam. THE LANCET CHILD & ADOLESCENT HEALTH 2020; 4:405-406. [PMID: 32213326 PMCID: PMC7118689 DOI: 10.1016/s2352-4642(20)30091-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/10/2020] [Accepted: 03/12/2020] [Indexed: 01/25/2023]
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Newly emerged enterovirus-A71 C4 sublineage may be more virulent than B5 in the 2015-2016 hand-foot-and-mouth disease outbreak in northern Vietnam. Sci Rep 2020; 10:159. [PMID: 31932599 PMCID: PMC6957505 DOI: 10.1038/s41598-019-56703-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 12/16/2019] [Indexed: 11/08/2022] Open
Abstract
Enterovirus-A71 (EV-A71) is a common cause of hand-foot-and-mouth disease (HFMD) and, rarely, causes severe neurological disease. This study aimed to elucidate the epidemiological and genetic characteristics and virulence of EV-A71 strains isolated from children diagnosed with HFMD. Rectal and throat swabs were collected from 488 children with HFMD in Hanoi, Vietnam, in 2015-2016. From 391 EV-positive patients, 15 EVs, including coxsackievirus A6 (CV-A6; 47.1%) and EV-A71 (32.5%, n = 127), were identified. Of the 127 EV-A71 strains, 117 (92.1%) were the B5 subgenotype and 10 (7.9%) were the C4 subgenotype. A whole-genome analysis of EV-A71 strains showed that seven of the eight C4a strains isolated in 2016 formed a new lineage, including two possible recombinants between EV-A71 C4 and CV-A8. The proportion of inpatients among C4-infected children was higher than among B5-infected children (80.0% vs. 27.4%; P = 0.002). The virulence of EV-A71 strains was examined in human scavenger receptor class B2 (hSCARB2)-transgenic mice, and EV-A71 C4 strains exhibited higher mortality than B5 strains (80.0% vs. 30.0%, P = 0.0001). Thus, a new EV-A71 C4a-lineage, including two possible recombinants between EV-A71 C4 and CV-A8, appeared in 2016 in Vietnam. The EV-A71 C4 subgenotype may be more virulent than the B5 subgenotype.
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Use and Outcomes of Antiretroviral Monotherapy and Treatment Interruption in Adolescents With Perinatal HIV Infection in Asia. J Adolesc Health 2019; 65:651-659. [PMID: 31395514 PMCID: PMC7007807 DOI: 10.1016/j.jadohealth.2019.05.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/22/2019] [Accepted: 05/28/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE Antiretroviral monotherapy and treatment interruption are potential strategies for perinatally HIV-infected adolescents (PHIVA) who face challenges maintaining effective combination antiretroviral therapy (ART). We assessed the use and outcomes for adolescents receiving monotherapy or undergoing treatment interruption in a regional Asian cohort. METHODS Regional Asian data (2001-2016) were analyzed to describe PHIVA who experienced ≥2 weeks of lamivudine or emtricitabine monotherapy or treatment interruption and trends in CD4 count and HIV viral load during and after episodes. Survival analyses were used for World Health Organization (WHO) stage III/IV clinical and immunologic event-free survival during monotherapy or treatment interruption, and a Poisson regression to determine factors associated with monotherapy or treatment interruption. RESULTS Of 3,448 PHIVA, 84 (2.4%) experienced 94 monotherapy episodes, and 147 (4.3%) experienced 174 treatment interruptions. Monotherapy was associated with older age, HIV RNA >400 copies/mL, younger age at ART initiation, and exposure to ≥2 combination ART regimens. Treatment interruption was associated with CD4 count <350 cells/μL, HIV RNA ≥1,000 copies/mL, ART adverse event, and commencing ART age ≥10 years compared with age <3 years. WHO clinical stage III/IV 1-year event-free survival was 96% and 85% for monotherapy and treatment interruption cohorts, respectively. WHO immunologic stage III/IV 1-year event-free survival was 52% for both cohorts. Those who experienced monotherapy or treatment interruption for more than 6 months had worse immunologic and virologic outcomes. CONCLUSIONS Until challenges of treatment adherence, engagement in care, and combination ART durability/tolerability are met, monotherapy and treatment interruption will lead to poor long-term outcomes.
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ID: 2036 Next-generation sequencing to evaluate frequency of BCR-ABL1 kinase domain Imatinib-resistance mutations. BIOMEDICAL RESEARCH AND THERAPY 2017. [DOI: 10.15419/bmrat.v4is.275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Chronic myeloid leukemia is a clonal myeloproliferative neoplasm, characterized by the presence of chromosomal translocation t(9; 22)(q34; q11). This is found in over 95% of the cases and results in the BCR-ABL1 fusion gene with high tyrosine kinase activity. During the last decades, imatinib and other generation of tyrosine kinase inhibitors have been used effectively for target therapy of the disease. However, many of the drug resistance cases have been reported recently, due to the mutation within kinase domain of the BCR-ABL1 fusion gene. In this work, we performed a retrospective study of 141 imatinib-resistance chronic myeloid leukemia patients to analyze kinase domain mutation by deep sequencing. Another group of 20 untreated patients were added as control. RNA from bone marrow cells was extracted and deeply sequenced utilizing Illumina MiSeq. Bioinformatics pipeline was applied for variant calling and annotation. And the Sanger sequencing was used to validate those mutations. The results showed that nearly one-fourth of patients harboring mutations that resist to Imatinib, among those, Y253F/H, M351T, G250E, F359V/I and M244V were the most frequent mutations. There were also a number of samples harboring multiple substitutions and new variations. Thus, Next-generation sequencing could be the sensitive and effective method to detect kinase domain mutation and our results could provide further information about the drug-resistance mutation in chronic myeloid leukemia.
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Low Risk of CD4 Decline After Immune Recovery in Human Immunodeficiency Virus-Infected Children With Viral Suppression. J Pediatric Infect Dis Soc 2017; 6:173-177. [PMID: 27295973 PMCID: PMC6251660 DOI: 10.1093/jpids/piw031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/09/2016] [Indexed: 11/12/2022]
Abstract
BACKGROUND. Regular CD4 count testing is often used to monitor antiretroviral therapy efficacy. However, this practice may be redundant in children with a suppressed human immunodeficiency virus (HIV) viral load. METHODS Study end points were as follows: (1) a CD4 count <200 cells/mm3 followed by a CD4 count ≥200 cells/mm3 (transient CD4 <200); (2) CD4 count <200 cells/mm3 confirmed within 6 months (confirmed CD4 <200); and (3) a new or recurrent World Health Organization (WHO) stage 3 or 4 illness (clinical failure). Kaplan-Meier curves and Cox regression were used to evaluate rates and predictors of transient CD4 <200, confirmed CD4 <200, and clinical failure among virally suppressed children aged 5-15 years who were enrolled in the TREAT Asia Pediatric HIV Observational Database. RESULTS Data from 967 children were included in the analysis. At the time of confirmed viral suppression, median age was 10.2 years, 50.4% of children were female, and 95.4% were perinatally infected with HIV. Median CD4 cell count was 837 cells/mm3, and 54.8% of children were classified as having WHO stage 3 or 4 disease. In total, 18 transient CD4 <200 events, 2 confirmed CD4 <200 events, and10 clinical failures occurred at rates of 0.73 (95% confidence interval [95% CI], 0.46-1.16), 0.08 (95% CI, 0.02-0.32), and 0.40 (95% CI, 0.22-0.75) events per 100 patient-years, respectively. CD4 <500 cells/mm3 at the time of viral suppression confirmation was associated with higher rates of both CD4 outcomes. CONCLUSIONS Regular CD4 testing may be unnecessary for virally suppressed children aged 5-15 years with CD4 ≥500 cells/mm3.
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A cross-sectional study to quantify the prevalence of avian influenza viruses in poultry at intervention and non-intervention live bird markets in central Vietnam, 2014. Transbound Emerg Dis 2017; 64:1991-1999. [PMID: 28120423 DOI: 10.1111/tbed.12605] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Indexed: 11/26/2022]
Abstract
In Vietnam, live bird markets are found in most populated centres, providing the means by which fresh poultry can be purchased by consumers for immediate consumption. Live bird markets are aggregation points for large numbers of poultry, and therefore, it is common for a range of avian influenza viruses to be mixed within live bird markets as a result of different poultry types and species being brought together from different geographical locations. We conducted a cross-sectional study in seven live bird markets in four districts of Thua Thien Hue Province in August and December, 2014. The aims of this study were to (i) document the prevalence of avian influenza in live bird markets (as measured by virus isolation); and (ii) quantify individual bird-, seller- and market-level characteristics that rendered poultry more likely to be positive for avian influenza virus at the time of sale. A questionnaire soliciting details of knowledge, attitude and avian influenza practices was administered to poultry sellers in study markets. At the same time, swabs and faecal samples were collected from individual poultry and submitted for isolation of avian influenza virus. The final data set comprised samples from 1,629 birds from 83 sellers in the seven live bird markets. A total of 113 birds were positive for virus isolation; a prevalence of 6.9 (95% CI 5.8-8.3) avian influenza virus-positive birds per 100 birds submitted for sale. After adjusting for clustering at the market and individual seller levels, none of the explanatory variables solicited in the questionnaire were significantly associated with avian influenza virus isolation positivity. The proportions of variance at the individual market, seller and individual bird levels were 6%, 48% and 46%, respectively. We conclude that the emphasis of avian influenza control efforts in Vietnam should be at the individual seller level as opposed to the market level.
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HIV-infected children in the Asia-Pacific region with baseline severe anemia: antiretroviral therapy and outcomes. ASIAN BIOMED 2016; 10:229-234. [PMID: 28239430 PMCID: PMC5321077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
BACKGROUND Severe anemia is common among children infected with human immunodeficiency virus (HIV). The choice of antiretroviral (ART) regimen needs careful consideration. No information is available regarding the initial ART regimens used in the Asia-Pacific region and the rate of switch of ART regimens in HIV-infected children with severe anemia. OBJECTIVES To study the initial ART regimens and the rate of switch of ART regimens used during the first 36 months in HIV-infected children with severe anemia and to evaluate their clinical and laboratory outcomes. METHODS We analyzed regional cohort data of 130 Asian children aged <18 years with baseline severe anemia (hemoglobin <7.5 g/dl) who started antiretroviral therapy (ART) between January 2003 and September 2013. RESULTS At ART initiation, median age was 3.5 years old (interquartile range (IQR) 1.7 to 6.3) and median hemoglobin was 6.7 g/dL (IQR 5.9-7.1, range 3.0-7.4). Initial ART regimens included stavudine (85.4%), zidovudine (13.8%), and abacavir (0.8%). In 81 children with available hemoglobin data after 6 months of ART, 90% recovered from severe anemia with a median hemoglobin of 10.7 g/dL (IQR 9.6-11.7, range 4.4-13.5). Those starting AZT-based ART had a mortality rate of 10.8 (95% confidence interval (CI) 4.8-23.9) per 100 patient-years compared to 2.7 (95% CI 1.6-4.6) per 100 patient-years among those who started d4T-based ART. CONCLUSIONS With the phase-out of stavudine, age-appropriate non-zidovudine options are needed for younger Asian children with severe anemia.
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Non-Nucleoside Reverse Transcriptase Inhibitor-Based Antiretroviral Therapy in Perinatally HIV-Infected, Treatment-Naïve Adolescents in Asia. J Adolesc Health 2016; 58:451-459. [PMID: 26803201 PMCID: PMC4808326 DOI: 10.1016/j.jadohealth.2015.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 11/22/2015] [Accepted: 11/25/2015] [Indexed: 11/29/2022]
Abstract
PURPOSE About a third of untreated, perinatally HIV-infected children reach adolescence. We evaluated the durability and effectiveness of non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based antiretroviral therapy (ART) in this population. METHODS Data from perinatally HIV-infected, antiretroviral-naïve patients initiated on NNRTI-based ART aged 10-19 years who had ≥6 months of follow-up were analyzed. Competing risk regression was used to assess predictors of NNRTI substitution and clinical failure (World Health Organization Stage 3/4 event or death). Viral suppression was defined as a viral load <400 copies/mL. RESULTS Data from 534 adolescents met our inclusion criteria (56.2% female; median age at treatment initiation 11.8 years). After 5 years of treatment, median height-for-age z score increased from -2.3 to -1.6, and median CD4+ cell count increased from 131 to 580 cells/mm(3). The proportion of patients with viral suppression after 6 months was 87.6% and remained >80% up to 5 years of follow-up. NNRTI substitution and clinical failure occurred at rates of 4.9 and 1.4 events per 100 patient-years, respectively. Not using cotrimoxazole prophylaxis at ART initiation was associated with NNRTI substitution (hazard ratio [HR], 1.5 vs. using; 95% confidence interval [CI] = 1.0-2.2; p = .05). Baseline CD4+ count ≤200 cells/mm(3) (HR, 3.3 vs. >200; 95% CI = 1.2-8.9; p = .02) and not using cotrimoxazole prophylaxis at ART initiation (HR, 2.1 vs. using; 95% CI = 1.0-4.6; p = .05) were both associated with clinical failure. CONCLUSIONS Despite late ART initiation, adolescents achieved good rates of catch-up growth, CD4+ count recovery, and virological suppression. Earlier ART initiation and routine cotrimoxazole prophylaxis in this population may help to reduce current rates of NNRTI substitution and clinical failure.
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The long-term outcomes of antiretroviral treatment initiated with mono or dual nucleoside reverse transcriptase inhibitors in HIV-1-infected children: an Asian observational study. J Virus Erad 2015. [DOI: 10.1016/s2055-6640(20)30502-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Two-year outcome of first-line antiretroviral therapy among HIV-1 vertically-infected children in Hanoi, Vietnam. Int J STD AIDS 2014; 26:821-30. [PMID: 25332224 DOI: 10.1177/0956462414556328] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 09/08/2013] [Indexed: 11/15/2022]
Abstract
A retrospective analysis of 86 HIV-1 vertically-infected Vietnamese children with a follow-up period >24 months after initiating antiretroviral therapy (ART) was performed from 2008 to 2012, to assess the outcome of first-line ART in resource-limited settings. Of the 86 children, 68 (79.1%) were treated successfully (plasma HIV-1 viral load [VL] <1000 copies/ml), and 63 (73.3%) had full viral suppression (VL <400 copies/ml) after 24 months of ART. No significant difference between successfully treated patients and failure groups was observed in VL, CD4(+) T-cell count or clinical stage at baseline; age at ART start; or ART regimen. All 14 children with VL >5000 copies/ml, one of four children with VL 1000-5000 copies/ml and none with VL <1000 copies/ml developed reverse transcriptase inhibitor (RTI)-resistance mutations by 24 months of ART. Y181C and M184V/I were the most dominant non-nucleoside and nucleoside RTI-resistance mutations, respectively (13/15, 86.7%). These findings suggest that VL testing after 24 months of ART can be used to efficiently differentiate ART failures among HIV-1 vertically-infected children in resource-limited settings.
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Abstract
Aging has been an important population trend of the twentieth century, with most elderly people living in developing countries. Little has been published on the healthcare needs of elderly in the Pacific Islands. The Pacific Islands Geriatric Education Center, at the University of Hawaii, has a mission to promote training in geriatric education in the Pacific Islands to improve healthcare to the elderly. The aim of this project was to develop and test a family caregiver training program for Palau and was achieved in two phases: (1) assessing needs by interviewing key informants and surveying elders and (2) evaluating the caregiver training program that was designed based on findings from the assessment. The Ecological Systems Theory provided the theoretical framework for this study. The needs assessment identified training and education of family caregivers as a top priority, with the Palauan culture of family caring for seniors presently threatened by caregiver burnout. Nearly all of the long-term care in Palau is provided by families, and elders have high prevalence of geriatric syndromes. A family caregiver train-the-trainer workshop was subsequently conducted in February 2011. Forty-four trainers, including 12 from other Pacific Islands, attended the workshop. To assess changes in knowledge and confidence to teach, we compared scores on pre- and post-questionnaires using paired t tests. The train-the-trainer workshop resulted in significantly improved self-assessed competence and confidence to teach in all geriatric syndromes, including dealing with difficult behaviors, gait and transfer training, caregiver stress relief, and resources for caregivers (p < 0.0001). This successful intervention identified geriatric care needs in Palau and successfully trained family caregivers to meet these needs, and may be used as a model for similar interventions in other Pacific Islands.
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Nuclear replacement of in vitro-matured porcine oocytes by a serial centrifugation and fusion method. Reprod Domest Anim 2009; 45:659-65. [PMID: 19144027 DOI: 10.1111/j.1439-0531.2008.01324.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of the present study was to establish a method for nuclear replacement in metaphase-II (M-II) stage porcine oocytes. Karyoplasts containing M-II chromosomes (K) and cytoplasts without chromosomes (C) were produced from in vitro-matured oocytes by a serial centrifugation method. The oocytes were then reconstructed by fusion of one karyoplast with 1, 2, 3 or 4 cytoplasts (K + 1C, K + 2C, K + 3C and K + 4C, respectively). Reconstructed oocytes, karyoplasts without fusion of any cytoplast (K) and zona-free M-II oocytes (control) were used for experiments. The rates of female pronucleus formation after parthenogenetic activation in all groups of reconstructed oocytes (58.2-77.4%) were not different from those of the K and control groups (58.2% and 66.0%, respectively). In vitro fertilization was carried out to assay the fertilization ability and subsequent embryonic development of the reconstructed oocytes. The cytoplast : karyoplast ratio did not affect the fertilization status (penetration and male pronuclear formation rates) of the oocytes. A significantly high monospermy rate was found in K oocytes (p < 0.05, 61.6%) compared with the other groups (18.2-32.8%). Blastocyst formation rates increased significantly as the number of the cytoplasts fused with karyoplasts increased (p < 0.05, 0.0-15.3%). The blastocyst rate in the K + 4C group (15.3%) was comparable with that of the control (17.8%). Total cell numbers in both the K + 3C and K + 4C groups (16.0 and 15.3 cells, respectively) were comparable with that of the control (26.2 cells). Our results demonstrate that a serial centrifugation and fusion (Centri-Fusion) is an effective method for producing M-II chromosome transferred oocytes with normal fertilization ability and in vitro development. It is suggested that the number of cytoplasts fused with a karyoplast plays a critical role in embryonic development.
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End-of-life care curriculum for internal medicine residents at the John A. Burns School of Medicine, University of Hawaii. HAWAII MEDICAL JOURNAL 2003; 62:128-9. [PMID: 12886728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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Immunomodulation of experimental autoimmune encephalomyelitis with ordered peptides based on MHC-TCR binding motifs. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:2688-93. [PMID: 11509612 DOI: 10.4049/jimmunol.167.5.2688] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T cell-mediated destruction of the myelin sheath causes inflammatory damage of the CNS in multiple sclerosis (MS). The major T and B cell responses in MS patients who are HLA-DR2 (about two-thirds of MS patients) react to a region between residues 84 and 103 of myelin basic protein (1 ). The crystal structure of HLA-DR2 complexed with myelin basic protein(84-102) confirmed that Lys(91) is the major TCR contact site, whereas Phe(90) is a major anchor to MHC and binds the hydrophobic P4 pocket (2 ). We have tested peptides containing repetitive 4-aa sequences designed to bind critical MHC pockets and to interfere with T cell activation. One such sequence, EYYKEYYKEYYK, ameliorates experimental autoimmune encephalomyelitis in Lewis rats, an animal model of MS.
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MESH Headings
- Adjuvants, Immunologic/pharmacology
- Amino Acid Sequence
- Animals
- Binding Sites/genetics
- Encephalomyelitis, Autoimmune, Experimental/drug therapy
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Female
- HLA-DR2 Antigen/metabolism
- Histocompatibility Antigens/metabolism
- Histocompatibility Antigens Class II/metabolism
- Humans
- Models, Molecular
- Molecular Sequence Data
- Multiple Sclerosis/drug therapy
- Multiple Sclerosis/immunology
- Myelin Basic Protein/genetics
- Myelin Basic Protein/immunology
- Myelin Basic Protein/pharmacology
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Peptide Fragments/pharmacology
- Peptides/genetics
- Peptides/immunology
- Peptides/pharmacology
- Rats
- Rats, Inbred Lew
- Receptors, Antigen, T-Cell/metabolism
- Sequence Homology, Amino Acid
- T-Lymphocytes/immunology
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Abstract
The Sulfur gene of tobacco is nuclearly encoded. A Su allele at this locus acts as a dominant semilethal mutation and causes reduced accumulation of chlorophyll, resulting in a yellow color in the plant. An engineered transposon tagging system, based upon the maize element Ac/Ds, was used to mutate the gene. High frequency of transposon excision from the Su locus produced variegated sectors. Plants regenerated from the variegated sector exhibited a similar variegated phenotype. Genetic analyses showed that the variegation was always associated with the transposase construct and the transposon was linked to the Su locus. Sequences surrounding the transposon were isolated, and five revertant sectors possessed typical direct repeats following Ds excisions. These genetic and molecular data are consistent with the tagging of the Su allele by the transposon.
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Abstract
Mature Arabidopsis seeds are enriched in storage proteins and lipids, but lack starch. In the shrunken seed 1 (sse1) mutant, however, starch is favored over proteins and lipids as the major storage compound. SSE1 has 26 percent identity with Pex16p in Yarrowia lipolytica and complements pex16 mutants defective in the formation of peroxisomes and the transportation of plasma membrane- and cell wall-associated proteins. In Arabidopsis maturing seeds, SSE1 is required for protein and oil body biogenesis, both of which are endoplasmic reticulum-dependent. Starch accumulation in sse1 suggests that starch formation is a default storage deposition pathway.
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Suppressive immunization with DNA encoding a self-peptide prevents autoimmune disease: modulation of T cell costimulation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 162:3336-41. [PMID: 10092787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Usually we rely on vaccination to promote an immune response to a pathogenic microbe. In this study, we demonstrate a suppressive from of vaccination, with DNA encoding a minigene for residues 139-151 of myelin proteolipid protein (PLP139-151), a pathogenic self-Ag. This suppressive vaccination attenuates a prototypic autoimmune disease, experimental autoimmune encephalomyelitis, which presents clinically with paralysis. Proliferative responses and production of the Th1 cytokines, IL-2 and IFN-gamma, were reduced in T cells responsive to PLP139-151. In the brains of mice that were successfully vaccinated, mRNA for IL-2, IL-15, and IFN-gamma were reduced. A mechanism underlying the reduction in severity and incidence of paralytic autoimmune disease and the reduction in Th1 cytokines involves altered costimulation of T cells; loading of APCs with DNA encoding PLP139-151 reduced the capacity of a T cell line reactive to PLP139-151 to proliferate even in the presence of exogenous CD28 costimulation. DNA immunization with the myelin minigene for PLP-altered expression of B7.1 (CD80), and B7.2 (CD86) on APCs in the spleen. Suppressive immunization against self-Ags encoded by DNA may be exploited to treat autoimmune diseases.
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MESH Headings
- Animals
- Autoantigens/administration & dosage
- Autoantigens/genetics
- Autoantigens/immunology
- Base Sequence
- Encephalomyelitis, Autoimmune, Experimental/etiology
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/prevention & control
- Female
- Immunosuppressive Agents/administration & dosage
- Immunosuppressive Agents/immunology
- Injections, Intramuscular
- Lymphocyte Activation/genetics
- Mice
- Mice, Inbred Strains
- Molecular Sequence Data
- Myelin Proteolipid Protein/administration & dosage
- Myelin Proteolipid Protein/genetics
- Myelin Proteolipid Protein/immunology
- Peptide Fragments/administration & dosage
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- T-Lymphocytes/immunology
- Th1 Cells/immunology
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
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Gene silencing from plant DNA carried by a Geminivirus. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1998; 14:91-100. [PMID: 15494056 DOI: 10.1046/j.1365-313x.1998.00101.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The geminivirus tomato golden mosaic virus (TGMV) replicates in nuclei and expresses genes from high copy number DNA episomes. The authors used TGMV as a vector to determine whether episomal DNA can cause silencing of homologous, chromosomal genes. Two markers were used to asses silencing: (1) the sulfur allele (su) of magnesium chelatase, an enzyme required for chlorophyll formation; and (2) the firefly luciferase gene (luc). Various portions of both marker genes were inserted into TGMV in place of the coat protein open-reading frame and the constructs were introduced into intact plants using particle bombardment. When TGMV vectors carrying fragments of su (TGMV::su) were introduced into leaves of wild type Nicotiana benthamiana, circular, yellow spots with an area of several hundred cells formed after 3-5 days. Systemic movement of TGMV::su subsequently produced varigated leaf and stem tissue. Fragments that caused silencing included a 786 bp 5' fragment of the 1392 bp su cDNA in sense and anti-sense orientation, and a 403 bp 3' fragment. TGMV::su-induced silencing was propogated through tissue culture, along with the viral episome, but was not retained through meiosis. Systemic downregulation of a constitutively expresse luciferase transgene in plants was achieved following infection with TGMV vectors carrying a 623 bp portion of luc in sense or anti-sense orientation. These results establish that homologous DNA sequences localized in nuclear episomes can modulate the expression of active chromosomal genes.
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Development and characterization of a generalized gene tagging system for higher plants using an engineered maize transposon Ac. PLANT MOLECULAR BIOLOGY 1992; 20:177-98. [PMID: 1327269 DOI: 10.1007/bf00014487] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
This report describes a series of transposon tagging vectors for dicotyledonous plants based on the maize transposable element Ac. This binary system includes the transposase (Ts) and the tagging element (Ds) on separate T-DNA vectors. Ts elements include versions in which transcription is driven either by the endogenous Ac promoter or by the cauliflower mosaic virus (CaMV) 35S promoter. Ds tagging element includes a gene conferring methotrexate (Mtx) resistance for selection and a supF gene to facilitate cloning of tagged sequences. The Ds element is flanked by a CaMV 35S promoter and the beta-glucuronidase (GUS) coding sequence so that GUS expression occurs upon excision of the element. We have transformed these Ts and Ds elements into tobacco and demonstrated that the Ts is functional with either promoter, and that the artificial Ds elements are capable of transposition. The amount of excision was found to depend upon both the individual Ts and Ds primary transformants used. Somatic excision of Ds was seen in up to 100% of progeny seedlings containing Ts and Ds. Germinal excision was detected in up to 48% of the progeny of plants containing both elements. Hence, this system can generate a sufficient number of events to be useful in gene tagging.
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