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The SARS-CoV-2 Omicron variant sparked the largest wave of infections worldwide. Mainland China eased its strict COVID-19 measures in late 2022 and experienced two nationwide Omicron waves in 2023. Here, we investigated lineage distribution and virus evolution in Guangdong, China, 2022-2023 by comparing 5813 local viral genomes with the datasets from other regions of China and worldwide. Additionally, we conducted three large-scale serological surveys involving 1696 participants to measure their immune response to the BA.5 and XBB.1.9 before and after the corresponding waves. Our findings revealed the Omicron variants, mainly the BA.5.2.48 lineage, causing infections in over 90% of individuals across different age groups within a month. This rapid spread led to the establishment of widespread immunity, limiting the virus's ability to further adaptive mutation and dissemination. While similar immune responses to BA.5 were observed across all age groups after the initial wave, children aged 3 to 11 developed a stronger cross immune response to the XBB.1.9 strain, possibly explaining their lower infection rates in the following XBB.1 wave. Reinfection with Omicron XBB.1 variant triggered a more potent neutralizing immune response among older adults. These findings highlight the impact of age-specific immune responses on viral spread in potential future waves.
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COVID-19 , Genoma Viral , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/imunologia , SARS-CoV-2/genética , China/epidemiologia , Criança , Pré-Escolar , Adulto , Adolescente , Pessoa de Meia-Idade , Adulto Jovem , Genoma Viral/genética , Masculino , Feminino , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Epidemiologia Molecular , Lactente , Idoso , Pandemias , FilogeniaRESUMO
Hand, Foot and Mouth Disease (HFMD) is a highly contagious viral illness primarily affecting children globally. A significant epidemiological transition has been noted in mainland China, characterized by a substantial increase in HFMD cases caused by non-Enterovirus A71 (EV-A71) and non-Coxsackievirus A16 (CVA16) enteroviruses (EVs). Our study conducts a retrospective examination of 36,461 EV-positive specimens collected from Guangdong, China, from 2013 to 2021. Epidemiological trends suggest that, following 2013, Coxsackievirus A6 (CVA6) and Coxsackievirus A10 (CVA10) have emerged as the primary etiological agents for HFMD. In stark contrast, the incidence of EV-A71 has sharply declined, nearing extinction after 2018. Notably, cases of CVA10 infection were considerably younger, with a median age of 1.8 years, compared to 2.3 years for those with EV-A71 infections, possibly indicating accumulated EV-A71-specific herd immunity among young children. Through extensive genomic sequencing and analysis, we identified the N136D mutation in the 2 A protein, contributing to a predominant subcluster within genogroup C of CVA10 circulating in Guangdong since 2017. Additionally, a high frequency of recombination events was observed in genogroup F of CVA10, suggesting that the prevalence of this lineage might be underrecognized. The dynamic landscape of EV genotypes, along with their potential to cause outbreaks, underscores the need to broaden surveillance efforts to include a more diverse spectrum of EV genotypes. Moreover, given the shifting dominance of EV genotypes, it may be prudent to re-evaluate and optimize existing vaccination strategies, which are currently focused primarily target EV-A71.
Assuntos
Genoma Viral , Genótipo , Doença de Mão, Pé e Boca , Filogenia , China/epidemiologia , Humanos , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Pré-Escolar , Lactente , Estudos Retrospectivos , Feminino , Masculino , Criança , Epidemiologia Molecular , Enterovirus/genética , Enterovirus/classificação , Enterovirus/isolamento & purificação , Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Genômica , Incidência , Adolescente , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologiaRESUMO
BACKGROUND: After the adjustment of COVID-19 epidemic policy, mainland China experienced two consecutive waves of Omicron variants within a seven-month period. In Guangzhou city, as one of the most populous regions, the viral infection characteristics, molecular epidemiology, and the dynamic of population immunity are still elusive. METHODS: We launched a prospective cohort study in the Guangdong Provincial CDC from December 2022 to July 2023. Fifty participants who received the same vaccination regimen and had no previous infection were recruited. RESULTS: 90% of individuals were infected with Omicron BA.5* variants within three weeks in the first wave. Thirteen cases (28.26%) experienced infection with XBB.1* variants, occurring from 14 weeks to 21 weeks after the first wave. BA.5* infections exhibited higher viral loads in nasopharyngeal sites compared to oropharyngeal sites. Compared to BA.5* infections, the XBB.1* infections had significantly milder clinical symptoms, lower viral loads, and shorter durations of virus positivity. The infection with the BA.5* variant elicited varying levels of neutralizing antibodies against XBB.1* among different individuals, even with similar levels of BA.5* antibodies. The level of neutralizing antibodies specific to XBB.1* determined the risk of reinfection. CONCLUSIONS: The rapid large-scale infections of the Omicron variants have quickly established herd immunity among the population in mainland China. In the future of the COVID-19 epidemic, a lower infection rate but a longer duration can be expected. Given the large population size and ongoing diversified herd immunity, it remains crucial to closely monitor the molecular epidemiology of SARS-CoV-2 for the emergence of new variants of concern in this region. Additionally, the timely evaluation of the immune status across different age groups is essential for informing future vaccination strategies and intervention policies.
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Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Carga Viral , Humanos , COVID-19/epidemiologia , COVID-19/virologia , COVID-19/imunologia , China/epidemiologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/classificação , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Estudos Prospectivos , Anticorpos Antivirais/sangue , Estudos de Coortes , Adulto Jovem , IdosoRESUMO
This study illustrated the effectiveness of the knowledge, attitude, practice (KAP) intervention model for community hypertension in the elderly by the community physician-led, describing the study design and baseline data. The aim of the study was to compare the changes in the elderly hypertensive population before and after the KAP intervention model by managing the elderly hypertensive patients for a period of 1 year. Basic information and risk factors affecting blood pressure control based on baseline data of recruited elderly hypertensive patients. The management approach consists of two parts: (1) the unified management of the community physician to whom the patient belongs; and (2) the management of the contracted patient by the community physician. The aim was to demonstrate the anti-hypertensive effectiveness (control rate, blood pressure reduction, and pulse pressure), the distribution of blood pressure types, and the change of the KAP in elderly hypertensive patients before and after the intervention. The KAP intervention model was administered to 2660 elderly hypertensive patients in a 1-year period. The blood pressure control rate improved by 54.03%. Mean values of overall systolic and diastolic blood pressure decreased by 16.00 and 5.31 mmHg, respectively. The proportion of isolated systolic hypertension (ISH) and systolic-diastolic hypertension (SDH) decreased by 29.14% and 24.81%, respectively. The KAP compliance improved significantly. These results suggest that the community physician-led KAP intervention model is effective in the management of hypertension in the elderly.
Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Conhecimentos, Atitudes e Prática em Saúde , Hipertensão , Humanos , Hipertensão/terapia , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Hipertensão/diagnóstico , Idoso , Masculino , Feminino , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Idoso de 80 Anos ou mais , Fatores de RiscoRESUMO
Biochar is preferentially recommended for the remediation of heavy metal-polluted soils. Sunflower is an important high-biomass oil crop with a promising potential for phytoremediation of Cr(VI)-polluted soil. However, how biochar affects sunflower growth and Cr accumulation in Cr(VI)-polluted soil needs to be elucidated. Here, a pot culture experiment was conducted to study whether soil amendment with biochar (0, 0.1%, 1%, and 5%, w/w) can mitigate Cr toxicity and accumulation in sunflower seedlings grown in soils artificially polluted with different levels of Cr(VI) (0, 50, and 250 mg Cr(VI)/kg soil). The addition of Cr(VI) exhibited significant phytotoxicity, as evidenced by inhibited plant growth and even the death of seedlings at 250 mg/kg Cr(VI). Overall, biochar amendment showed positive effects on plant growth and Cr immobilization, dependent on both the biochar dose and Cr addition level. When 50 mg/kg Cr(VI) was added, 1% biochar showed positive effects similar to 5% biochar on improving plant growth and mineral nutrition (particularly K), reducing Cr content in shoots and roots, and decreasing Cr availability and Cr(VI) content in the soil. In comparison with non-amendment, 1% and 5% biochar caused 85% and 100% increase in shoot dry weights, and 75% and 86% reduction in shoot Cr concentrations, respectively. When 250 mg/kg Cr(VI) was added, a 5% dose produced much better benefits than 1%, while a 0.1% dose did not help plants to survive. Overall, an appropriate dose of biochar enhanced Cr(VI) immobilization and subsequently decreased its toxicity and accumulation in sunflower seedlings. Our findings confirm that biochar can be used as an efficient amendment for the remediation of Cr(VI)-polluted soils and cleaner production of sunflower oil and biomass.
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Repeated morphine exposure has been shown to induce neuronal plasticity in reward-related areas of the brain. miR-132, a CREB-induced and activation-dependent microRNA, has been suggested to be involved in the neuronal plasticity by increasing neuronal dendritic branches and spinogenesis. However, it is still unclear whether miR-132 is related to morphine dependence. Here, we investigate whether miR-132 is involved in morphine dependence and whether it is related to the structural plasticity of the dentate gyrus (DG) neurons. Sprague-Dawley rats are treated with increasing doses of morphine injection for six consecutive days to develop morphine dependence. Our results show that dendritic branching and spinogenesis of the DG neurons of morphine dependent rats are increased. Morphine treatment (24 h) promotes the differentiation of N2a cells stably expressing µ-opioid receptor by up-regulating miR-132 expression. Moreover, inhibiting miR-132 3p (but not 5p) of the DG neurons can reverse the structural plasticity and disrupt the formation of morphine dependence in rats. These findings indicate that miR-132 in the DG neurons is involved in morphine dependence via modifying the neuronal plasticity.
Assuntos
Giro Denteado/efeitos dos fármacos , MicroRNAs/metabolismo , Dependência de Morfina/fisiopatologia , Plasticidade Neuronal/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Receptores Opioides mu/efeitos dos fármacosRESUMO
Understanding the temporal and spatial patterns of soil water extraction and their impacts on growth response of winter wheat to deficit subsurface drip irrigation (SDI) conditions is critical for managing water scarcity and stabilizing yield. A field experiment was conducted from 2016 to 2018 involving five SDI amounts: 0.25, 0.4, 0.6, 0.8, and 1.0 ETc, representing 25, 40, 60, 80, and 100% of crop evapotranspiration (ETc), respectively. The results showed that the 0.6 ETc treatment significantly increased soil water extraction from 40-80 and 80-140-cm from jointing to maturity as compared to the 1.0 ETc treatment. Whereas the 0.8 ETc treatment significantly increased soil water extraction from 80-140-cm deep soil from flowering to maturity in the first growing season. The crop was most water-stressed under the 0.25 and 0.4 ETc treatments, thus extracted more soil water from 0-140-cm soil profile. However, both treatments exhibited minimum plant tillers, lowest leaf water content, leaf area index (LAI), photosynthetic rate (P n ), and transpiration rate (T r ) as well as grain yield. All these parameters, except for leaf water content, P n after the flowering stage, and grain productivity, were also reduced in the 0.6 ETc treatment than the 1.0 ETc treatment. The differences between the 0.8 and 1.0 ETc treatments were minor in terms of plant height, LAI, spike number, P n and T r , but infertile tillers were fewer in the 0.8 ETc treatment. We obtained high yield from the 0.8 ETc treatment, and the 0.6ETc treatment resulted in the highest harvest index with improved WUE than other treatments. Integrating deficit irrigation into SDI can save water in winter wheat production in water-limited regions, which can not only enhance soil water extraction from deep soil layers, but also sustained yield by stimulating crop growth. Therefore, a deficit SDI system would be used to conserve water in water-limited regions.
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Re-exposure to drug or drug-associated cues after withdrawal can induce behavioral sensitization expression in animals or increase in the expected effect to drug in humans, which mean an enhanced drug seeking/taking motivation to trigger relapse after abstinence. The Nucleus accumbens (NAc) is known to play a key role in mediating this motivation. Recently, it has been shown that systemic administration of orexin receptor 1 (OXR1) antagonist attenuates animals' motivation behavior to take drug by self-administration paradigm, which is more effectively than orexin receptor 2 (OXR2) antagonist. However, the effect of OXR1 in the NAc on drug-induced locomotor sensitization remains elusive. The present study was designed to investigate the effect of OXR1 in the NAc on chronic cocaine-induced locomotor sensitization. Rats were given 10 mg/kg cocaine intraperitoneal injection (i.p.) for five consecutive days, followed by 10 mg/kg cocaine re-exposure (challenge) on the 14th day of withdrawal. Results showed that re-exposure to cocaine after withdrawal could induce locomotor sensitization expression in cocaine-sensitized rats. Simultaneously, the number of OXR1 positive neurons and OXR1 membrane protein level in the NAc core but not the shell were significantly increased following the cocaine re-exposure. Further, micro-infusion of SB-334867, an OXR1 selective antagonist, into the NAc core but not the shell before cocaine re-exposure, significantly attenuated the expression of locomotor sensitization in rats. The findings demonstrate that OXR1 in the NAc core partially mediates the expression of chronic cocaine-induced locomotor sensitization.
Assuntos
Comportamento Animal/efeitos dos fármacos , Benzoxazóis/farmacologia , Sensibilização do Sistema Nervoso Central/efeitos dos fármacos , Cocaína/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Locomoção/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Naftiridinas/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Ureia/análogos & derivados , Animais , Benzoxazóis/administração & dosagem , Cocaína/administração & dosagem , Inibidores da Captação de Dopamina/administração & dosagem , Masculino , Proteínas Mitocondriais/antagonistas & inibidores , Naftiridinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Ureia/administração & dosagem , Ureia/farmacologiaRESUMO
MicroRNA-132 (miR-132), a small RNA that regulates gene expression, is known to promote neurogenesis in the embryonic nervous system and adult brain. Although exposure to psychoactive substances can increase miR-132 expression in cultured neural stem cells (NSCs) and the adult brain of rodents, little is known about its role in opioid addiction. So, we set out to determine the effect of miR-132 on differentiation of the NSCs and whether this effect is involved in opioid addiction using the rat morphine self-administration (MSA) model. We found that miR-132 overexpression enhanced the differentiation of NSCs in vivo and in vitro. Similarly, specific overexpression of miR-132 in NSCs of the adult hippocampal dentate gyrus (DG) during the acquisition stage of MSA potentiated morphine-seeking behavior. These findings indicate that miR-132 is involved in opioid addiction, probably by promoting the differentiation of NSCs in the adult DG.
Assuntos
Diferenciação Celular , Giro Denteado/metabolismo , MicroRNAs/metabolismo , Células-Tronco Neurais/metabolismo , Transtornos Relacionados ao Uso de Opioides/metabolismo , Animais , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Masculino , Ratos Sprague-DawleyRESUMO
The controlled size and surface treatment of magnetic nanoparticles (NPs) make one-stage combination feasible for enhanced magnetic resonance imaging (MRI) contrast and effective hyperthermia. However, superparamagnetic behavior, essential for avoiding the aggregation of magnetic NPs, substantially limits their performance. Here, a superparamagnetic core-shell structure is developed, which promotes the formation of vortex-like intraparticle magnetization structures in the remanent state, leading to reduced dipolar interactions between two neighboring NPs, while during an MRI scan, the presence of a DC magnetic field induces the formation of NP chains, introducing increased local inhomogeneous dipole fields that enhance relaxivity. The core-shell NPs also reveal an augmented anisotropy, due to exchange coupling to the high anisotropy core, which enhances the specific absorption rate. This in vivo tumor study reveals that the tumor cells can be clearly diagnosed during an MRI scan and the tumor size is substantially reduced through hyperthermia therapy by using the same FePt@iron oxide nanoparticles, realizing the concept of theranostics.
RESUMO
The prelimbic cortex (PL) and infralimbic cortex (IL) play a role in context-induced reinstatement of heroin seeking in an animal model of drug relapse. Both the PL and IL receive direct glutamatergic projections from the ventral CA1 (vCA1), which is also involved in context-induced reinstatement of cocaine and heroin seeking. Here we studied the role of vCA1-PL and vCA1-IL projections in context-induced reinstatement of heroin seeking by using electrophysiological, neuropharmacological, chemogenetic, and molecular methods. We showed that context-induced reinstatement of heroin seeking caused selective activation of the vCA1-IL but not vCA1-PL glutamatergic projections, decreased synaptosomal GluA2 expression in the IL, impaired basal synaptic transmission, and facilitation of long-term depression (LTD) in the vCA1-IL pathway. Additionally, chemogenetic inactivation of the vCA1-IL but not vCA1-PL pathway decreased context-induced reinstatement of heroin seeking. Inactivation of the vCA1-IL pathway also reversed synaptosomal GluA2 downregulation and basal transmission reduction, and blocked LTD induction. Taken together, our results demonstrate a critical role of the vCA1-IL glutamatergic projection in context-induced reinstatement of heroin seeking in a rat model of drug relapse.
Assuntos
Região CA1 Hipocampal/metabolismo , Comportamento de Procura de Droga/fisiologia , Ácido Glutâmico/metabolismo , Dependência de Heroína/metabolismo , Animais , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/patologia , Comportamento de Procura de Droga/efeitos dos fármacos , Heroína/administração & dosagem , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/fisiologia , Masculino , Entorpecentes/administração & dosagem , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Vias Neurais/patologia , Distribuição Aleatória , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Autoadministração , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismoRESUMO
Repeated exposure to psychostimulants induces a long-lasting enhancement of locomotor activity called behavioral sensitization, which is often reinforced by stress after drug withdrawal. The mechanisms underlying these phenomena remain elusive. Here we explored the effects of acute stress 3 or 14 days after the cessation of chronic cocaine treatment on the expression of locomotor sensitization induced by a cocaine challenge in rats and the key brain region and molecular mechanism underlying the phenomenon. A single session of forced swimming, as an acute stress (administered 2 days after the cessation of cocaine), significantly enhanced the expression of cocaine locomotor sensitization 14 days after the final cocaine injection (challenge at 12 days after acute stress) but not 3 days after the cessation of cocaine (challenge at 1 day after acute stress). The result indicated that acute stress enhanced the expression of cocaine locomotor sensitization after incubation for 12 days rather than 1 day after the last cocaine injection. Moreover, the enhancement in locomotor sensitization was paralleled by a selective increase in the number of the c-Fos+ cells, the level of CRFR1 mRNA in the ventromedial caudate putamen (vmCPu). Furthermore, the enhancement was significantly attenuated by CRFR1 antagonist NBI-27914 into the vmCPu, implying that the up-regulation of CRFR1 in the vmCPu seems to be critical in the acute stress-enhanced expression of cocaine locomotor sensitization. The findings demonstrate that the long-term effect of acute stress on the expression of cocaine locomotor sensitization is partially mediated by CRFR1 in the vmCPu.
Assuntos
Anestésicos Locais/efeitos adversos , Cocaína/efeitos adversos , Atividade Motora/efeitos dos fármacos , Putamen/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Estresse Psicológico/patologia , Síndrome de Abstinência a Substâncias/fisiopatologia , Análise de Variância , Compostos de Anilina/farmacologia , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Pirimidinas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Receptores de Hormônio Liberador da Corticotropina/genética , Natação/psicologia , Fatores de TempoRESUMO
This paper reports a flexible and stretchable metamaterial-based "skin" or meta-skin with tunable frequency selective and cloaking effects in microwave frequency regime. The meta-skin is composed of an array of liquid metallic split ring resonators (SRRs) embedded in a stretchable elastomer. When stretched, the meta-skin performs as a tunable frequency selective surface with a wide resonance frequency tuning range. When wrapped around a curved dielectric material, the meta-skin functions as a flexible "cloaking" surface to significantly suppress scattering from the surface of the dielectric material along different directions. We studied frequency responses of multilayer meta-skins to stretching in a planar direction and to changing the spacing between neighboring layers in vertical direction. We also investigated scattering suppression effect of the meta-skin coated on a finite-length dielectric rod in free space. This meta-skin technology will benefit many electromagnetic applications, such as frequency tuning, shielding, and scattering suppression.
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A pot culture experiment was conducted to study the effects of postponing nitrogen (N) application on photosynthetic characteristics and grain yield of winter wheat subjected to water stress after heading stage. Equal in the total N rate in winter wheat growth season, N application was split before sowing, and/or at jointing and /or at anthesis at the ratio of 10:0:0 (N1), 6:4:0 (N2) and 4:3:3 (N3), combined with unfavorable water condition (either waterlogged or drought) with the sufficient water condition as control. The results showed that, under each of the water condition, both N2 and N3 treatments significantly improved the leaf photosynthetic rate and the SPAD value of flag leaf compared with N1 treatment during grain filling stage, and also the crop ear number, grain number per spike and above-ground biomass were increased. Although postponing nitrogen application increased water consumption, both grain yield and water use efficiency were increased. Compared with sufficient water supply, drought stress and waterlogging stress significantly reduced the photosynthetic rate of flag leaves at anthesis and grain filling stages, ear number, 1000-grain mass and yield under all of the N application patterns. The decline of photosynthetic rate under either drought stress or waterlogging stress was much less in N2 and N3 than in N1 treatments, just the same as the grain yield. The results indicated that postponing nitrogen application could regulate winter wheat yield as well as its components to alleviate the damages, caused by unfavorable water stress by increasing flag leaf SPAD and maintaining flag leaf photosynthetic rate after anthesis, and promoting above-ground dry matter accumulation.