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1.
J Hazard Mater ; 471: 134464, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38688219

RESUMO

Developing highly efficient adsorbents for the removal of trace thallium(I) (Tl+) is crucial for addressing environmental challenges. In this study, we successfully synthesized cubic Prussian blue (PB) loading on filter papers using an intermediate layer (dopamine/polyethyleneimine) via in-situ methods. The as-prepared PB-modified FP demonstrated outstanding anti-interference properties and light-enhanced adsorption performance for Tl+ (0.5 mg/L) under ultraviolet (UV) irradiation, exhibiting twice the effectiveness compared to dark conditions, even in acidic and coexisting ionic environments. This indicated its suitability for treating complex Tl+-contaminated water. Notably, the removal efficiency for trace Tl+ was almost 100%, with a maximum experimental adsorption capacity of 86.2 mg/g after 1-h photo-promoted adsorption under 365 nm UV. Characterization results supported a proposed photo-driven redox mechanism that elucidated the interaction between Tl+ and PB-modified FP. Specifically, the accelerated Fe(III) to Fe(II) redox reaction facilitated Tl+ accommodation on the surface and/or lattice of PB, enhancing Tl+ adsorption by compensating for missed positive charges. This study provides valuable insights into utilizing PB-based materials to enhance the photo-enhanced Tl+ adsorption capacity in a cost-effective, easy-to-synthesize, and environmentally friendly manner.

2.
Toxics ; 11(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36850967

RESUMO

Arsenic (As) is extremely toxic to living organisms at high concentrations. Arsenobetaine (AsB), confirmed to be a non-toxic form, is the main contributor to As in the muscle tissue of marine fish. However, few studies have investigated the biotransformation and biodegradation of AsB in mammals. In the current study, C57BL/6J mice were fed four different diets, namely, Yangjiang and Zhanjiang fish diets spiked with marine fish muscle containing AsB, and arsenite (As(III)) and arsenate (As(V)) diets spiked with As(III) and As(V), respectively, to investigate the biotransformation and bioaccumulation of AsB in mouse tissues for 42 d. Different diets exhibited different As species distributions, which contributed to varying levels of As bioaccumulation in different tissues. The intestines accumulated the highest level of As, regardless of form, which played a major part in As absorption and distribution in mice. We observed a significant biotransformation of AsB to As(V) following its diet exposure, and the liver, lungs, and spleen of AsB-treated mice showed higher As accumulation levels than those of As(III)- or As(V)-treated mice. Inorganic As showed relatively high accumulation levels in the lungs and spleen after long-term exposure to AsB. Overall, these findings provided strong evidence that AsB undergoes biotransformation to As(V) in mammals, indicating the potential health risk associated with long-term AsB intake in mammals.

3.
Influenza Other Respir Viruses ; 17(1): e13067, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36394198

RESUMO

BACKGROUND: Estimation of influenza disease burden is crucial for optimizing intervention strategies against seasonal influenza. This study aimed to estimate influenza-associated excess respiratory and circulatory (R&C) and all-cause (AC) mortality among older adults aged 65 years and above in mainland China from 2011 to 2016. METHODS: Through a systematic review, we collected influenza-associated excess R&C and AC mortality data of older adults aged 65 years and above for specific cities/provinces in mainland China. Generalized linear models were fitted to estimate the corresponding excess mortality for older adults by province and nationwide, accounting for the potential variables of influenza virus activity, demography, economics, meteorology, and health service. All statistical analyses were conducted using R software. RESULTS: A total of 9154 studies were identified in English and Chinese databases, and 11 (0.1%) were included in the quantitative synthesis after excluding duplicates and screening the title, abstract, and full text. Using a generalized linear model, the estimates of annual national average influenza-associated excess R&C and AC mortality among older adults aged 65 years and above were 111.8 (95% CI: 92.8-141.1) and 151.6 (95% CI: 127.6-179.3) per 100,000 persons, respectively. Large variations in influenza-associated excess R&C and AC mortality among older adults were observed among 30 provinces. CONCLUSIONS: Influenza was associated with substantial excess R&C and AC mortality among older adults aged 65 years and above in China from 2011 to 2016. This analysis provides valuable evidence for the introduction of the influenza vaccine into the National Immunization Program for the elderly in China.


Assuntos
Vacinas contra Influenza , Influenza Humana , Orthomyxoviridae , Idoso , Humanos , Influenza Humana/complicações , Influenza Humana/epidemiologia , Estações do Ano , China/epidemiologia
4.
BMC Med ; 19(1): 173, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34315454

RESUMO

BACKGROUND: The rapid process of research and development and lack of follow-up time post-vaccination aroused great public concern about the safety profile of COVID-19 vaccine candidates. To provide comprehensive overview of the safety profile of COVID-19 vaccines by using meta-analysis technique. METHODS: English-language articles and results posted on PubMed, Embase, Web of Science, PMC, official regulatory websites, and post-authorization safety surveillance data were searched through June 12, 2021. Publications disclosing safety data of COVID-19 candidate vaccines in humans were included. A meta-analysis of proportions was performed to estimate the pooled incidence and the pooled rate ratio (RR) of safety outcomes of COVID-19 vaccines using different platforms. RESULTS: A total of 87 publications with safety data from clinical trials and post-authorization studies of 19 COVID-19 vaccines on 6 different platforms were included. The pooled rates of local and systemic reactions were significantly lower among inactivated vaccines (23.7%, 21.0%), protein subunit vaccines (33.0%, 22.3%), and DNA vaccines (39.5%, 29.3%), compared to RNA vaccines (89.4%, 83.3%), non-replicating vector vaccines (55.9%, 66.3%), and virus-like particle vaccines (100.0%, 78.9%). Solicited injection-site pain was the most common local reactions, and fatigue and headache were the most common systemic reactions. The frequency of vaccine-related serious adverse events was low (< 0.1%) and balanced between treatment groups. Vaccine platforms and age groups of vaccine recipients accounted for much of the heterogeneity in safety profiles between COVID-19 vaccines. Reporting rates of adverse events from post-authorization observational studies were similar to results from clinical trials. Crude reporting rates of adverse events from post-authorization safety monitoring (passive surveillance) were lower than in clinical trials and varied between countries. CONCLUSIONS: Available evidence indicates that eligible COVID-19 vaccines have an acceptable short-term safety profile. Additional studies and long-term population-level surveillance are strongly encouraged to further define the safety profile of COVID-19 vaccines.


Assuntos
COVID-19 , Vacinas , Adolescente , Idoso , Idoso de 80 Anos ou mais , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Humanos , Pessoa de Meia-Idade , SARS-CoV-2 , Vacinas/efeitos adversos
5.
Nat Hum Behav ; 5(8): 1009-1020, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34158650

RESUMO

COVID-19 vaccination is being conducted in over 200 countries and regions to control SARS-CoV-2 transmission and return to a pre-pandemic lifestyle. However, understanding when non-pharmaceutical interventions (NPIs) can be lifted as immunity builds up remains a key question for policy makers. To address this, we built a data-driven model of SARS-CoV-2 transmission for China. We estimated that, to prevent the escalation of local outbreaks to widespread epidemics, stringent NPIs need to remain in place at least one year after the start of vaccination. Should NPIs alone be capable of keeping the reproduction number (Rt) around 1.3, the synergetic effect of NPIs and vaccination could reduce the COVID-19 burden by up to 99% and bring Rt below the epidemic threshold in about 9 months. Maintaining strict NPIs throughout 2021 is of paramount importance to reduce COVID-19 burden while vaccines are distributed to the population, especially in large populations with little natural immunity.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , COVID-19/transmissão , Vacinação , China , Surtos de Doenças/prevenção & controle , Humanos
6.
medRxiv ; 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33564776

RESUMO

COVID-19 vaccination is being conducted in over 190 countries/regions to control SARS-CoV-2 transmission and return to a pre-pandemic lifestyle. However, understanding when non-pharmaceutical interventions (NPIs) can be lifted as immunity builds up remain a key question for policy makers. To address it, we built a data-driven model of SARS-CoV-2 transmission for China. We estimated that to prevent the escalation of local outbreaks to widespread epidemics, stringent NPIs need to remain in place at least one year after the start of vaccination. Should NPIs alone be capable to keep the reproduction number (R t ) around 1.3, the synergetic effect of NPIs and vaccination could reduce up to 99% of COVID-19 burden and bring R t below the epidemic threshold in about 9 months. Maintaining strict NPIs throughout 2021 is of paramount importance to reduce COVID-19 burden while vaccines are distributed to the population, especially in large populations with little natural immunity.

7.
Res Sq ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33594357

RESUMO

COVID-19 vaccination programs have been initiated in several countries to control SARS-CoV-2 transmission and return to a pre-pandemic lifestyle. However, understanding when non-pharmaceutical interventions (NPIs) can be lifted as vaccination builds up and how to update priority groups for vaccination in real-time remain key questions for policy makers. To address these questions, we built a data-driven model of SARS-CoV-2 transmission for China. We estimated that, to prevent local outbreaks to escalate to major widespread epidemics, stringent NPIs need to remain in place at least one year after the start of vaccination. Should NPIs be capable to keep the reproduction number (Rt) around 1.3, a vaccination program could reduce up to 99% of COVID-19 burden and bring Rt below the epidemic threshold in about 9 months. Maintaining strict NPIs throughout 2021 is of paramount importance to reduce COVID-19 burden while vaccines are distributed to the population, especially in large populations with little natural immunity.

8.
BMC Med ; 19(1): 45, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33563270

RESUMO

BACKGROUND: All countries are facing decisions about which population groups to prioritize for access to COVID-19 vaccination after the first vaccine products have been licensed, at which time supply shortages are inevitable. Our objective is to define the key target populations, their size, and priority for a COVID-19 vaccination program in the context of China. METHODS: On the basis of utilitarian and egalitarian principles, we define and estimate the size of tiered target population groups for a phased introduction of COVID-19 vaccination, considering evolving goals as vaccine supplies increase, detailed information on the risk of illness and transmission, and past experience with vaccination during the 2009 influenza pandemic. Using publicly available data, we estimated the size of target population groups, and the number of days needed to vaccinate 70% of the target population. Sensitivity analyses considered higher vaccine coverages and scaled up vaccine delivery relative to the 2009 pandemic. RESULTS: Essential workers, including staff in the healthcare, law enforcement, security, nursing homes, social welfare institutes, community services, energy, food and transportation sectors, and overseas workers/students (49.7 million) could be prioritized for vaccination to maintain essential services in the early phase of a vaccination program. Subsequently, older adults, individuals with underlying health conditions and pregnant women (563.6 million) could be targeted for vaccination to reduce the number of individuals with severe COVID-19 outcomes, including hospitalizations, critical care admissions, and deaths. In later stages, the vaccination program could be further extended to target adults without underlying health conditions and children (784.8 million), in order to reduce symptomatic infections and/or to stop virus transmission. Given 10 million doses administered per day, and a two-dose vaccination schedule, it would take 1 week to vaccinate essential workers but likely up to 7 months to vaccinate 70% of the overall population. CONCLUSIONS: The proposed framework is general but could assist Chinese policy-makers in the design of a vaccination program. Additionally, this exercise could be generalized to inform other national and regional strategies for use of COVID-19 vaccines, especially in low- and middle-income countries.


Assuntos
Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Pessoal de Saúde , Programas de Imunização/métodos , Seleção de Pacientes , Polícia , Adolescente , Idoso , COVID-19/epidemiologia , COVID-19/mortalidade , Criança , China/epidemiologia , Comorbidade , Teoria Ética , Feminino , Indústria Alimentícia , Prioridades em Saúde , Hospitalização , Humanos , Programas de Imunização/organização & administração , Lactente , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Mortalidade , Casas de Saúde , Pandemias/prevenção & controle , Formulação de Políticas , Gravidez , SARS-CoV-2 , Meios de Transporte , Vacinação , Adulto Jovem
9.
BMJ ; 371: m4704, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33323388

RESUMO

OBJECTIVE: To provide global, regional, and national estimates of target population sizes for coronavirus disease 2019 (covid-19) vaccination to inform country specific immunisation strategies on a global scale. DESIGN: Descriptive study. SETTING: 194 member states of the World Health Organization. POPULATION: Target populations for covid-19 vaccination based on country specific characteristics and vaccine objectives (maintaining essential core societal services; reducing severe covid-19; reducing symptomatic infections and stopping virus transmission). MAIN OUTCOME MEASURE: Size of target populations for covid-19 vaccination. Estimates use country specific data on population sizes stratified by occupation, age, risk factors for covid-19 severity, vaccine acceptance, and global vaccine production. These data were derived from a multipronged search of official websites, media sources, and academic journal articles. RESULTS: Target population sizes for covid-19 vaccination vary markedly by vaccination goal and geographical region. Differences in demographic structure, presence of underlying conditions, and number of essential workers lead to highly variable estimates of target populations at regional and country levels. In particular, Europe has the highest share of essential workers (63.0 million, 8.9%) and people with underlying conditions (265.9 million, 37.4%); these two categories are essential in maintaining societal functions and reducing severe covid-19, respectively. In contrast, South East Asia has the highest share of healthy adults (777.5 million, 58.9%), a key target for reducing community transmission. Vaccine hesitancy will probably impact future covid-19 vaccination programmes; based on a literature review, 68.4% (95% confidence interval 64.2% to 72.6%) of the global population is willing to receive covid-19 vaccination. Therefore, the adult population willing to be vaccinated is estimated at 3.7 billion (95% confidence interval 3.2 to 4.1 billion). CONCLUSIONS: The distribution of target groups at country and regional levels highlights the importance of designing an equitable and efficient plan for vaccine prioritisation and allocation. Each country should evaluate different strategies and allocation schemes based on local epidemiology, underlying population health, projections of available vaccine doses, and preference for vaccination strategies that favour direct or indirect benefits.


Assuntos
Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Densidade Demográfica , Regionalização da Saúde/métodos , SARS-CoV-2/imunologia , Cobertura Vacinal , COVID-19/virologia , Saúde Global , Prioridades em Saúde , Humanos , Programas de Imunização , Organização Mundial da Saúde
10.
medRxiv ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33024985

RESUMO

Background COVID-19 vaccine prioritization and allocation strategies that maximize health benefit through efficient use of limited resources are urgently needed. We aimed to provide global, regional, and national estimates of target population sizes for COVID-19 vaccination to inform country-specific immunization strategies on a global scale. Methods Based on a previous study of international allocation for pandemic COVID-19 vaccines, we classified the entire world population into eleven priority groups. Information on priority groups was derived from a multi-pronged search of official websites, media sources and academic journal articles. The sizes of different priority groups were projected for 194 countries globally. Results Overall, the size of COVID-19 vaccine recipient population varied markedly by goals of the vaccination program and geography. The general population aged <60 years without any underlying condition accounts for the majority of the total population (5.2 billion people, 68%), followed by 2.3 billion individuals at risk of severe disease, and 46.9 million essential workers which are critical to maintaining a functional society. Differences in the demographic structure, presence of underlying conditions, and number of essential workers led to highly variable estimates of target populations both at the WHO region and country level. In particular, Europe has the highest share of essential workers (6.8%) and the highest share of individuals with underlying conditions (37.8%), two priority categories to maintain societal functions and reduce severe burden. In contrast, Africa has the highest share of healthy adults, school-age individuals, and infants (77.6%), which are the key groups to target to reduce community transmission. Interpretation The sizeable distribution of target groups on a country and regional bases underlines the importance of equitable and efficient vaccine prioritization and allocation globally. The direct and indirect benefits of COVID-19 vaccination should be balanced by considering local differences in demography and health.

11.
Cell ; 177(4): 865-880.e21, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31031002

RESUMO

Circular RNAs (circRNAs) produced from back-splicing of exons of pre-mRNAs are widely expressed, but current understanding of their functions is limited. These RNAs are stable in general and are thought to have unique structural conformations distinct from their linear RNA cognates. Here, we show that endogenous circRNAs tend to form 16-26 bp imperfect RNA duplexes and act as inhibitors of double-stranded RNA (dsRNA)-activated protein kinase (PKR) related to innate immunity. Upon poly(I:C) stimulation or viral infection, circRNAs are globally degraded by RNase L, a process required for PKR activation in early cellular innate immune responses. Augmented PKR phosphorylation and circRNA reduction are found in peripheral blood mononuclear cells (PBMCs) derived from patients with autoimmune disease systemic lupus erythematosus (SLE). Importantly, overexpression of the dsRNA-containing circRNA in PBMCs or T cells derived from SLE can alleviate the aberrant PKR activation cascade, thus providing a connection between circRNAs and SLE.


Assuntos
RNA Circular/metabolismo , RNA Circular/fisiologia , eIF-2 Quinase/metabolismo , Adolescente , Adulto , Doenças Autoimunes/genética , Linhagem Celular , Endorribonucleases/metabolismo , Feminino , Humanos , Imunidade Inata/genética , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/genética , Pessoa de Meia-Idade , Fosforilação , RNA/metabolismo , Splicing de RNA/genética , Estabilidade de RNA/fisiologia , RNA Circular/genética , RNA de Cadeia Dupla/metabolismo , Viroses/metabolismo , eIF-2 Quinase/imunologia
12.
Front Plant Sci ; 8: 1468, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28878800

RESUMO

Taxus spp. is a highly valuable medicinal plant with multiple pharmacological effects on various cancers. Cytochrome P450s (CYP450s) play important roles in the biosynthesis of active compounds in Taxus spp., such as the famous diterpenoid, Taxol. However, some specific CYP450 enzymes involved in the biosynthesis of Taxol remain unknown, and the systematic identification of CYP450s in Taxus has not been reported. In this study, 118 full-length and 175 partial CYP450 genes were identified in Taxus chinensis transcriptomes. The 118 full-length genes were divided into 8 clans and 29 families. The CYP71 clan included all A-type genes (52) belonging to 11 families. The other seven clans possessed 18 families containing 66 non-A-type genes. Two new gymnosperm-specific families were discovered, and were named CYP864 and CYP947 respectively. Protein sequence alignments revealed that all of the T. chinensis CYP450s hold distinct conserved domains. The expression patterns of all 118 CYP450 genes during the long-time subculture and MeJA elicitation were analyzed. Additionally, the expression levels of 15 novel CYP725 genes in different Taxus species were explored. Considering all the evidence, 6 CYP725s were identified to be candidates for Taxol biosynthesis. The cis-regulatory elements involved in the transcriptional regulation were also identified in the promoter regions of CYP725s. This study presents a comprehensive overview of the CYP450 gene family in T. chinensis and can provide important insights into the functional gene studies of Taxol biosynthesis.

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