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1.
Mol Biol Rep ; 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34743272

RESUMO

BACKGROUND: As an alpine plant, Rhododendron chrysanthum (R. chrysanthum) has evolved cold resistance mechanisms and become a valuable plant resource with the responsive mechanism of cold stress. METHODS AND RESULTS: We adopt the phosphoproteomic and proteomic analysis combining with physiological measurement to illustrate the responsive mechanism of R. chrysanthum seedling under cold (4 °C) stress. After chilling for 12 h, 350 significantly changed proteins and 274 significantly changed phosphoproteins were detected. Clusters of Orthologous Groups (COG) analysis showed that significantly changed phosphoproteins and proteins indicated cold changed energy production and conversion and signal transduction. CONCLUSIONS: The results indicated photosynthesis was inhibited under cold stress, but cold induced calcium-mediated signaling, reactive oxygen species (ROS) homeostasis and other transcription regulation factors could protect plants from the destruction caused by cold stress. These data provide the insight to the cold stress response and defense mechanisms of R. chrysanthum leaves at the phosphoproteome level.

2.
Nat Commun ; 12(1): 5654, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34580297

RESUMO

There is an urgent need for animal models to study SARS-CoV-2 pathogenicity. Here, we generate and characterize a novel mouse-adapted SARS-CoV-2 strain, MASCp36, that causes severe respiratory symptoms, and mortality. Our model exhibits age- and gender-related mortality akin to severe COVID-19. Deep sequencing identified three amino acid substitutions, N501Y, Q493H, and K417N, at the receptor binding domain (RBD) of MASCp36, during in vivo passaging. All three RBD mutations significantly enhance binding affinity to its endogenous receptor, ACE2. Cryo-electron microscopy analysis of human ACE2 (hACE2), or mouse ACE2 (mACE2), in complex with the RBD of MASCp36, at 3.1 to 3.7 Å resolution, reveals the molecular basis for the receptor-binding switch. N501Y and Q493H enhance the binding affinity to hACE2, whereas triple mutations at N501Y/Q493H/K417N decrease affinity and reduce infectivity of MASCp36. Our study provides a platform for studying SARS-CoV-2 pathogenesis, and unveils the molecular mechanism for its rapid adaptation and evolution.


Assuntos
COVID-19/diagnóstico , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/metabolismo , Substituição de Aminoácidos , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Sítios de Ligação/genética , COVID-19/mortalidade , COVID-19/virologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Ligação Proteica/genética , Domínios Proteicos/genética , SARS-CoV-2/genética , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/genética
3.
Front Cell Infect Microbiol ; 11: 728415, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34466405

RESUMO

Background: The second human pegivirus (HPgV-2) and hepatitis C virus (HCV) belong to the Flaviviridae family and share some common genome features. However, the two viruses exhibit significantly different genetic diversity. The comparison of intrahost dynamics of HPgV-2 and HCV that mainly reflect virus-host interactions is needed to elucidate their intrahost difference of genetic diversity and the possible mechanisms. Methods: Intrahost single nucleotide variations (iSNVs) were identified by means of next-generation sequencing from both cross-sectional and longitudinal samples from HPgV-2- and HCV-coinfected patients. The levels of human cytokines were quantified in the patient before and after HCV elimination by the treatment of direct-acting antivirals (DAA). Results: Unlike HCV, the viral sequences of HPgV-2 are highly conserved among HPgV-2-infected patients. However, iSNV analysis confirmed the intrahost variation or quasispecies of HPgV-2. Almost all iSNVs of HPgV-2 did not accumulate or transmit within host over time, which may explain the highly conserved HPgV-2 consensus sequence. Intrahost variation of HPgV-2 mainly causes nucleotide transition in particular at the 3rd codon position and synonymous substitutions, indicating purifying or negative selection posed by host immune system. Cytokine data further indicate that HPgV-2 infection alone may not efficiently stimulate innate immune responses since proinflammatory cytokine expression dramatically decreased with elimination of HCV. Conclusion: This study provided new insights into the intrahost genomic variations and evolutionary dynamics of HPgV-2 as well as the impact of host immune selection and virus polymerase on virus evolution. The different genetic diversity of HPgV-2 and HCV makes HPgV-2 a potential new model to investigate RNA virus diversity and the mechanism of viral polymerase in modulating virus replication.


Assuntos
Infecções por Flaviviridae , Hepatite C Crônica , Hepatite C , Antivirais , Estudos Transversais , Infecções por Flaviviridae/complicações , Hepacivirus/genética , Hepatite C/complicações , Humanos , Pegivirus , Filogenia , RNA Viral
4.
Metab Eng ; 68: 86-93, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34555495

RESUMO

Coenzyme Q (CoQ) is vital for energy metabolism in living organisms. In humans, CoQ10 deficiency causes diseases and must be replenished via diet; however, CoQ content in plant foods is primarily low. Here, we report the breeding of high CoQ10 tomato lines by expressing four enzymes with a fruit-specific promoter, which modifies the chloroplast chorismate pathway, enhances cytosolic isoprenoid biosynthesis, and up-regulates the first two reactions in mitochondrion that construct the CoQ10 polyisoprenoid tail. We show that, while the level of the aromatic precursor could be markedly elevated, head group prenylation is the key to increasing the final CoQ10 yield. In the HUCD lines expressing all four transgenes, the highest CoQ10 content (0.15 mg/g dry weight) shows a seven-fold increase from the wild-type level and reaches an extraordinarily rich CoQ10 food grade. Overviewing the changes in other terpenoids by transcriptome and metabolic analyses reveals variable contents of carotenoids and α-tocopherol in the HUCD lines. In addition to the enigmatic relations among different terpenoid pathways, high CoQ10 plants maintaining substantial levels of either vitamin can be selected. Our investigation paves the way for the development of CoQ10-enriched crops as dietary supplements.


Assuntos
Lycopersicon esculentum , Ubiquinona , Carotenoides/metabolismo , Frutas/metabolismo , Humanos , Lycopersicon esculentum/genética , Mitocôndrias , Ubiquinona/genética
5.
J Affect Disord ; 294: 375-381, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34315099

RESUMO

BACKGROUND: Victimization as an inducing factor of depressive symptoms has been confirmed in previous studies. However, little is known about how and when it induces depressive symptoms in adolescents. METHODS: In total, 1174 Chinese adolescents were recruited to complete the Juvenile Victimization Questionnaire, Security Questionnaire, Positive Psychological Capital Questionnaire, and the Chinese version of the Center for Epidemiologic Studies Depression Scale. RESULTS: After controlling for gender and school type, the sense of security partially mediated the association between victimization and depressive symptoms. Moreover, direct association and the mediating effect of the sense of security were moderated by psychological capital. The moderating effect occurred in the second half of the mediating effect. LIMITATIONS: Causal conclusions cannot be drawn based on cross-sectional research design. All measures were based on participant self-report. CONCLUSIONS: The mediating model constructed in this study emphasized the important influence of stress, emotion, and psychological diathesis on adolescent depressive symptoms.


Assuntos
Bullying , Vítimas de Crime , Adolescente , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Humanos
6.
Virus Res ; 301: 198455, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34015364

RESUMO

Mosquitoes interact with a wide range of viruses including both arboviruses and insect-specific viruses. This study aimed to characterize the RNA viruses that are interacting with Mansonia wilsoni and Coquillettidia hermanoi mosquito species. The total RNA extracted from mosquito pools were sequenced on a Ion torrent platform. Viral contigs were identified against viral databases and their evolutionary relationship were reconstructed. We identified a total of 107 viral sequences, 11 of which were assigned as endogenous viral elements, and at least six known viral families were identified. Phylogenetic reconstructions were performed for 4 viral families. All Mansoniini viruses investigated through phylogenetic analysis are closely related to insect-specific viruses found in other mosquito species although with considerable divergence at the amino acid level, suggesting that we have detected new viral lineages. This study enhanced our understanding about the virome of two sylvatic Mansoniini mosquitoes.

8.
Signal Transduct Target Ther ; 6(1): 145, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33859168

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) is an emerging tick-borne virus with high fatality and an expanding endemic. Currently, effective anti-SFTSV intervention remains unavailable. Favipiravir (T-705) was recently reported to show in vitro and in animal model antiviral efficacy against SFTSV. Here, we conducted a single-blind, randomized controlled trial to assess the efficacy and safety of T-705 in treating SFTS (Chinese Clinical Trial Registry website, number ChiCTR1900023350). From May to August 2018, laboratory-confirmed SFTS patients were recruited from a designated hospital and randomly assigned to receive oral T-705 in combination with supportive care or supportive care only. Fatal outcome occurred in 9.5% (7/74) of T-705 treated patients and 18.3% (13/71) of controls (odds ratio, 0.466, 95% CI, 0.174-1.247). Cox regression showed a significant reduction in case fatality rate (CFR) with an adjusted hazard ratio of 0.366 (95% CI, 0.142-0.944). Among the low-viral load subgroup (RT-PCR cycle threshold ≥26), T-705 treatment significantly reduced CFR from 11.5 to 1.6% (P = 0.029), while no between-arm difference was observed in the high-viral load subgroup (RT-PCR cycle threshold <26). The T-705-treated group showed shorter viral clearance, lower incidence of hemorrhagic signs, and faster recovery of laboratory abnormities compared with the controls. The in vitro and animal experiments demonstrated that the antiviral efficacies of T-705 were proportionally induced by SFTSV mutation rates, particularly from two transition mutation types. The mutation analyses on T-705-treated serum samples disclosed a partially consistent mutagenesis pattern as those of the in vitro or animal experiments in reducing the SFTSV viral loads, further supporting the anti-SFTSV effect of T-705, especially for the low-viral loads.

9.
Clin Rehabil ; 35(7): 999-1010, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33517744

RESUMO

OBJECTIVE: The aim of the study was to investigate whether liuzijue qigong could improve the ability of respiratory control and comprehensive speech in patients with stroke dysarthria. DESIGN: A randomized controlled trial. SETTING: The research was carried out in the department of rehabilitation. PARTICIPANTS: Altogether, a total of 98 stroke patients with dysarthria participated in the study. INTERVENTIONS: Patients were randomly divided into two groups (the experimental group: basic articulation + liuzijue qigong, 48 patients or the control group: basic articulation + traditional breathing training, 50 patients). All therapies were conducted once a day, five times a week for three weeks. MAIN MEASURES: Primary outcome measure: Speech breathing level of the modified Frenchay Dysarthria Assessment. Secondary outcome measures: the modified Frenchay Dysarthria Assessment, maximum phonation time, maximal counting ability, /s/, /z/, s/z ratio, and the loudness level. All outcome measures were assessed twice (at baseline and after three weeks). RESULTS: At three weeks, There were significant difference between the two groups in the change of speech breathing level (81% vs 66%, P = 0.011), the modified Frenchay Dysarthria Assessment (5.54 (4.68-6.40) vs 3.66 (2.92-4.40), P = 0.001), maximum phonation time (5.55 (4.92-6.18) vs 3.01(2.31-3.71), P < 0.01), maximal counting ability (3.08(2.45-3.71) vs 2.10 (1.53-2.67), P = 0.018), and /s/ (3.08 (2.39-3.78) vs 1.87 (1.23-2.51), P = 0.004), while no significant differences were found in the change of /z/ (3.08 (2.31-3.86) vs 2.10 (1.5-2.64), P = 0.08), s/z ratio (1.26 (0.96-1.55) vs 1.03 (0.97-1.09), P = 0.714), and the change of loudness level (69% vs 60%, P = 0.562). CONCLUSIONS: Liuzijue qigong, combined with basic articulation training, could improve the respiratory control ability, as well as the comprehensive speech ability of stroke patients with dysarthria. TRIAL REGISTRATION: ChiCTR-INR-16010215.


Assuntos
Exercícios Respiratórios , Disartria/reabilitação , Qigong , Idoso , Disartria/etiologia , Feminino , Humanos , Masculino , Fonação , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/métodos
10.
Ann Transl Med ; 9(1): 23, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33553316

RESUMO

Background: This study aimed to develop an interactive vision screening tool based on desktop autostereoscopy and evaluate its feasibility for testing visual acuity, colour vision, stereo vision and binocular balance clinically. Methods: An interactive desktop autostereoscopy vision test was developed making it remarkably convenient for individuals to undergo multiple visual function assessments in a single test. With this rapid screening process, an individual's visual acuity, colour vision, stereo vision and binocular balance can be assessed within several minutes. A total of 155 healthy subjects were enrolled to compare the clinical repeatability, accuracy, inter-visit variability, likeability and efficiency between the autostereoscopy and traditional method. Results: In the repeatability test, the visual acuity measured with autostereoscopy was 0.045±0.018 and 0.035±0.018 (P=0.702) for the first and second tests, respectively. The mean logarithm of the Minimum Angle of Resolution (logMAR) visual acuities measured with the Early Treatment Diabetic Retinopathy Study (EDTRS) chart and autostereoscopy test were 0.04±0.02 and 0.05±0.02, respectively, which were not significantly different (P=0.849). The correlation between these two kinds of tests was statistically significant (Spearman correlation coefficient =0.829, P<0.001). The results for colour vision, stereo vision, and binocular vision are presented, and the effectiveness of the autostereoscopic method is supported with qualitative data comparing its results with those of the traditional methods. In the likeability test, the EDTRS chart and autostereoscopy test had scores of 2.21±0.53 and 3.04±0.07, while the traditional and autostereoscopy tests for colour vision, stereo vision, and binocular vision had scores of 2.02±0.59 and 3.36±0.93, respectively (P<0.001). Regarding visual fatigue, the mean scores were 0.69±0.04 and 0.42±0.04 (P<0.001) with the EDTRS chart and autostereoscopy test, respectively. Regarding work efficiency, the average testing times per person was 59.65±0.66 and 48.92±0.86 s (P<0.001) with the EDTRS chart and autostereoscopy test, respectively. Conclusions: The autostereoscopy test was conclusively shown to be valid, efficient and repeatable for the measurement of visual acuity, colour vision, stereo vision, and binocular vision, and the process was subjectively well-liked and comfortable.

11.
Qual Life Res ; 30(3): 721-728, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33068235

RESUMO

PURPOSE: At present, it is not clear about the influence of health-promoting lifestyle, aging perceptions, social support, and other psychosocial factors on elderly depression. This study aims to explore the mediating role of aging perceptions between health-promoting lifestyle and elderly depression, and the moderating role of social support in the mediating process. METHODS: A cross-sectional survey was conducted among 359 elderly people in six districts of a city. The Chinese version of the Health-Promoting Lifestyle Profile-II (HPLP-IIR), the Brief Aging Perceptions Questionnaire (B-PQ), the Center for Epidemiological Studies Depression Scale (CES-DR), and the Social Support Rate Scale (SSRS) were conducted and recollected on the spot. Stepwise analysis was used to test the mediating effect and moderating effect, and age and gender variables were controlled. RESULTS: The results showed the following: (1) health-promoting lifestyle is an important influencing factor of elderly depression; (2) aging perceptions plays a mediating role in the relationship between health-promoting lifestyle and elderly depression, accounting for 31.8% of the total utility; and (3) social support plays a moderating role between aging perceptions and elderly depression, with a high level of social support. The effect of aging perceptions on depression is less than that of the elderly with low social support level. CONCLUSION: Health-promoting lifestyle influence the depression of elderly people through aging perceptions and social support moderates the influence of aging perceptions on the elderly depression.


Assuntos
Depressão/psicologia , Estilo de Vida Saudável/fisiologia , Qualidade de Vida/psicologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Apoio Social , Inquéritos e Questionários
12.
Arch Phys Med Rehabil ; 102(3): 423-430, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795561

RESUMO

OBJECTIVES: To compare the effects of Liuzijue Qigong and conventional respiratory training on trunk control ability and respiratory muscle functions in patients at an early recovery stage from stroke. DESIGN: A single-blind, randomized controlled trial. SETTING: A hospital. PARTICIPANTS: Patients (N=60) within 2 months poststroke. INTERVENTIONS: The experimental group (n=30) received conventional rehabilitation training combined with Liuzijue exercise, and the control group (n=30) received conventional rehabilitation training combined with conventional respiration training. The training in the 2 groups was conducted 5 times per week for 3 weeks. MAIN OUTCOME MEASURES: Trunk Impairment Scale (TIS), maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), maximum expiratory mid-flow (MMEF), diaphragmatic movement, the change of intra-abdominal pressure (IAP), Berg Balance Scale (BBS), and Modified Barthel Index (MBI). All outcome measures were assessed twice (at baseline and 3 weeks). RESULTS: Both groups significantly improved in TIS, MIP, FVC, PEF, and the change of IAP, BBS, and MBI when pre- and postassessments (P<.05) were compared. Compared with the control group, there was a significant difference in the experimental group in the static sitting balance subscale (P=.014), dynamic balance subscale (P=.001), coordination subscale (P<.001), TIS total scores (P<.001; effect size [ES]=0.9), MIP (P=.012; 95% confidence interval [CI], 2.23-17.69; ES=0.67), MEP (P=.015; 95% CI, 1.85-16.57; ES=0.65), change of IAP (P=.001), and MBI (P=.016; 95% CI, 1.51-14.16; ES=0.64). No significant differences were found between the 2 groups in FEV1 (P=.24), FVC (P=.43), PEF (P=.202), MMEF (P=.277), the diaphragmatic movement of quiet breathing (P=.146), deep breathing (P=.102), and BBS (P=.124). CONCLUSIONS: Liuzijue exercise showed more changes than conventional respiratory training in improving trunk control ability, respiratory muscle functions, and activities of daily living ability in patients at an early recovery stage from stroke.


Assuntos
Equilíbrio Postural/fisiologia , Qigong/métodos , Músculos Respiratórios/fisiopatologia , Terapia Respiratória/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Tronco/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Método Simples-Cego
14.
Folia Microbiol (Praha) ; 65(6): 925-936, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33064268

RESUMO

Klebsiella pneumoniae (family Enterobacteriaceae) is a gram-negative bacterium that has strong pathogenicity to humans and can cause sepsis, pneumonia, and urinary tract infection. In recent years, the unreasonable use of antibacterial drugs has led to an increase in drug-resistant strains of K. pneumoniae, a serious threat to public health. Bacteriophages, viruses that infect bacteria, are ubiquitous in the natural environment. They are considered to be the most promising substitute for antibiotics because of their high specificity, high efficiency, high safety, low cost, and short development cycle. In this study, a novel phage designated vB_KpnP_IME279 was successfully isolated from hospital sewage using a multidrug-resistant strain of K. pneumoniae as an indicator. A one-step growth curve showed that vB_KpnP_IME279 has a burst size of 140 plaque-forming units/cell and a latent period of 20 min at its optimal multiplicity of infection (MOI = 0.1). Phage vB_KpnP_IME279 survives in a wide pH range between 3 and 11 and is stable at temperatures ranging from 40 to 60 °C. Ten of the 20 strains of K. pneumoniae including the host bacteria were lysed by the phage vB_KpnP_IME279, and the multilocus sequence typing and wzi typing of the 10 strains were ST11, ST37, ST375, wzi209, wzi52, and wzi72, respectively. The genome of vB_KpnP_IME279 is 42,518 bp long with a G + C content of 59.3%. Electron microscopic observation showed that the phage belongs to the family Podoviridae. BLASTN alignment showed that the genome of the phage has low similarity with currently known phages. The evolutionary relationship between phage vB_KpnP_IME279 and other Podoviridae was analyzed using a phylogenetic tree based on sequences of phage major capsid protein and indicates that the phage vB_KpnP_IME279 belongs to the Podoviridae subfamily. These data enhance understanding of K. pneumoniae phages and will help in development of treatments for multidrug-resistant bacteria using phages.


Assuntos
Bacteriófagos/classificação , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Klebsiella pneumoniae/virologia , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Bacteriófagos/fisiologia , Composição de Bases , Farmacorresistência Bacteriana Múltipla , Genoma Viral , Hospitais , Especificidade de Hospedeiro , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Técnicas Microbiológicas , Tipagem de Sequências Multilocus , Filogenia , Podoviridae/classificação , Podoviridae/genética , Podoviridae/isolamento & purificação , RNA Ribossômico 16S , Esgotos/microbiologia , Esgotos/virologia , Temperatura , Sequenciamento Completo do Genoma
15.
Sci Rep ; 10(1): 16628, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024229

RESUMO

Experimental animals including the ferret, marmoset, woodchuck, mini pig, and tree shrew have been used in biomedical research. However, their gut microbiota have not been fully investigated. In this study, the gut microbiota of these five experimental animals were analyzed with 16S rRNA sequencing. The phyla Firmicutes, Bacteroidetes, and Fusobacteria were present in the gut microbiota of all the species. Specific phyla were present in different animals: Proteobacteria in the ferret, Tenericutes in the marmoset, and Spirochaetes in the mini pig. Fusobacterium and unidentified Clostridiales were the dominant genera in the ferret, whereas Libanicoccus, Lactobacillus, Porphyromonas, and Peptoclostridium were specific to marmoset, mini pig, woodchuck, and tree shrew, respectively. A clustering analysis showed that the overall distribution of microbial species in the guts of these species mirrored their mammalian phylogeny, and the microbiota of the marmoset and tree shrew showed the closest bray_curtis distances to that of humans. PICRUSt functional prediction separated the woodchuck from the other species, which may reflect its herbivorous diet. In conclusion, both the evolutionary phylogeny and daily diet affect the gut microbiota of these experimental animals, which should not be neglected for their usage in biomedical research.


Assuntos
Animais de Laboratório/microbiologia , Callithrix/microbiologia , Dieta/veterinária , Fezes/microbiologia , Furões/microbiologia , Microbioma Gastrointestinal , Marmota/microbiologia , Porco Miniatura/microbiologia , Tupaiidae/microbiologia , Animais , Feminino , Microbioma Gastrointestinal/genética , Masculino , Filogenia , RNA Ribossômico 16S , Suínos
16.
Front Microbiol ; 11: 1407, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903329

RESUMO

The rapid expansion of Acinetobacter baumannii clinical isolates exhibiting resistance to most or all available antibiotics is a global concern. Current treatments for infections caused by this bacterium have become less effective, and the need to explore new alternative therapies is urgent. Depolymerases derived from phages are emerging as attractive anti-virulence agents. In this study, a previously isolated A. baumannii phage (designated as vB_AbaM_IME285) was characterized, and genomic study was carried out using various bioinformatics tools. A gene predicted as encoding for the depolymerase was cloned and expressed, and the depolymerase activity of the recombinant enzyme (Dp49) was identified both in vitro and in experimental mice. The results showed that phage IME285 formed translucent halos around the plaques when inoculated onto a lawn of the host bacteria, exibiting depolymerase activity against this strain. On the basis of complete genome sequencing and bioinformatics analysis, ORF49 was speculated to be a gene encoding for the putative capsule depolymerase. The expressed recombinant Dp49 displayed an effective depolymerase activity and had a spectrum of activity similar to its parental phage IME285, which was active against 25 out of 49 A. baumannii strains. It was found that Dp49 greatly improved the inhibitory effect of serum on bacterial growth in vitro, and the administration of this enzyme significantly increased the survival rates of A. baumannii-infected mice in the animal experiment. In conclusion, the phage-encoded depolymerase Dp49 might be a promising alternative means of controlling infections mediated by multidrug-resistant A. baumannii.

17.
Science ; 369(6511): 1603-1607, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32732280

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic has prioritized the development of small-animal models for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We adapted a clinical isolate of SARS-CoV-2 by serial passaging in the respiratory tract of aged BALB/c mice. The resulting mouse-adapted strain at passage 6 (called MASCp6) showed increased infectivity in mouse lung and led to interstitial pneumonia and inflammatory responses in both young and aged mice after intranasal inoculation. Deep sequencing revealed a panel of adaptive mutations potentially associated with the increased virulence. In particular, the N501Y mutation is located at the receptor binding domain (RBD) of the spike protein. The protective efficacy of a recombinant RBD vaccine candidate was validated by using this model. Thus, this mouse-adapted strain and associated challenge model should be of value in evaluating vaccines and antivirals against SARS-CoV-2.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Camundongos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Administração Intranasal , Enzima de Conversão de Angiotensina 2 , Animais , Betacoronavirus/genética , Betacoronavirus/patogenicidade , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/imunologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunogenicidade da Vacina , Pulmão/virologia , Doenças Pulmonares Intersticiais/virologia , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Mutação , Peptidil Dipeptidase A/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Virais/administração & dosagem , Virulência/genética
18.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795413

RESUMO

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Assuntos
RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
19.
Infect Genet Evol ; 85: 104454, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32634600

RESUMO

Beilong virus (BeiV), a member of the newly recognized genus Jeilongvirus of family Paramyxoviridae, has been reported with limited geographic and host scopes, only in Hongkong, China and from two rat species. Here, by next-generation sequencing (NGS) on dominant wild small animal species in 4 provinces in China, we obtained a complete sequence of BeiV strain from Rattus norvegicus in Guangdong, neighboring HongKong, China. We then made an expanded epidemiological investigation in 11 provinces to obtain the geographic distribution and genetic features of this virus. Altogether 7168 samples from 2005 animals (1903 rodents, 100 shrews, 2 mustelidaes) that belonged to 33 species of Cricetidae, Muridae, Sciuridae and Dipodidae family of Rodentia, 3 species of Soricidae family of Soricomorpha, 2 species of Mustelidae family of Carnivora were examined by RT-PCR and sequencing. A positive rate of 3.7% (266/7168) was obtained that was detected from 22 animal species, including 5 species of Cricetidae family, 12 species of Muridae family, 2 species of Sciuridae family and 3 species of Soricidae family. Phylogenetic analyses based on 154 partial Large gene sequences grouped the current BeiV into two lineages, that were related to their geographic regions and animal hosts. Our study showed the wide distribution of BeiV in common species of wild rodents and shrews in China, highlighting the necessity of epidemiological study in wider regions.

20.
Arch Virol ; 165(6): 1489-1494, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32266550

RESUMO

We detected a novel bovine hepacivirus N (HNV) subtype, IME_BovHep_01, in the serum of cattle in Tengchong, Yunnan, China, by high-throughput sequencing. The complete genome of IME_BovHep_01, was sequenced using an Illumina MiSeq sequencer and found to be 8850 nt in length, encoding one hypothetical protein. BLASTn analysis showed that the genome sequence shared similarity with the bovine hepacivirus isolate BovHepV_209/Ger/2014, with 88% query coverage and 70.8% identity. However, the highest similarity was to bovine hepacivirus N strain BRBovHep_RS963, for which only a partial genome sequence is available, with 68% query coverage and 81.5% identity. Sequence comparisons and phylogenetic analysis suggested that IME_BovHep_01 is a novel HNV subtype. Importantly, IME_BovHep_01 is the first member of this new genotype for which the complete genome sequence was determined.


Assuntos
Bovinos/virologia , Genoma Viral , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Animais , Sequência de Bases , China , Variação Genética , Genótipo , Hepacivirus/classificação , Filogenia , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
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