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1.
Transbound Emerg Dis ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33559368

RESUMO

The variety and widespread of coronavirus in natural reservoir animals is likely to cause epidemics via interspecific transmission, which has attracted much attention due to frequent coronavirus epidemics in recent decades. Birds are natural reservoir of various viruses, but the existence of coronaviruses in wild birds in central China has been barely studied. Some bird coronaviruses belongs to the genus of Deltacoronavirus. To explore the diversity of bird deltacoronaviruses in central China, we tested fecal samples from 415 wild birds in Hunan Province, China. By RT-PCR detection, we identified eight samples positive for deltacoronaviruses which were all from common magpies, and in four of them, we successfully amplified complete deltacoronavirus genomes distinct from currently known deltacoronavirus, indicating four novel deltacoronavirus stains (HNU1-1, HNU1-2, HNU2 and HNU3) . Comparative analysis on the four genomic sequences showed that these novel magpie deltacoronaviruses shared three different S genes among which the S genes of HNU1-1 and HNU1-2 showed 93.8% amino acid (aa) identity to that of thrush coronavirus HKU12, HNU2 S showed 71.9% aa identity to that of White-eye coronavirus HKU16, and HKU3 S showed 72.4% aa identity to that of sparrow coronavirus HKU17. Recombination analysis showed that frequent recombination events of the S genes occurred among these deltacoronavirus strains. Two novel putative cleavage sites separating the nonstructural proteins in the HNU coronaviruses were found. Bayesian phylogeographic analysis showed that the south coast of China might be a potential origin of bird deltacoronaviruses existing in inland China. In summary, these results suggest that common magpie in China carries diverse deltacoronaviruses with novel genomic features, indicating an important source of environmental coronaviruses closed to human communities, which may provide key information for prevention and control of future coronavirus epidemics.

2.
Sustain Cities Soc ; 63: 102466, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32904401

RESUMO

The novel human coronavirus (SARS-CoV-2) causes the coronavirus disease 2019 (COVID-19) pandemic worldwide. Control of COVID-19 pandemic is vital for public health and is the prerequisite to maintain social stability. However, the origin and transmission route of SARS-CoV-2 is unclear, bringing huge difficult to virus control. Monitoring viral variation and screening functional mutation sites are crucial for prevention and control of infectious diseases. In this study, we developed a user-friendly software, named BioAider, for quick sequence annotation and mutation analysis on large-scale genome-sequencing data. Herein, we detected 14 substitution hotspots within 3,240 SARS-CoV-2 genome sequences, including 3 groups of potentially linked substitution. NSP13-Y541C was crucial substitution which might affect the unwinding activity of the viral helicase. In particular, we discovered a SR-rich region of SARS-CoV-2 distinct from SARS-CoV, indicating more complex replication mechanism and unique N-M interaction of SARS-CoV-2. Interestingly, the quantity of SSRX repeat fragments in SARS-CoV-2 provided further evidence of its animal origin. Overall, we developed an efficient tool for rapid identification of viral genome mutations which could facilitate viral genomic studies. Using this tool, we have found critical clues for the transmission route of SARS-CoV-2 which would provide theoretical support for the epidemic control of pathogenic coronaviruses.

3.
Transbound Emerg Dis ; 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32794346

RESUMO

Coronavirus (CoV) pandemics have become a huge threat to the public health worldwide in the recent decades. Typically, severe acute respiratory syndrome CoV (SARS-CoV) caused SARS pandemic in 2003 and SARS-CoV-2 caused the ongoing COVID-19 pandemic. Both viruses are most likely originated from bats. Thus, direct or indirect inter-species transmission from bats to humans is required for the viruses to cause pandemics. Receptor utilization is a key factor determining the host range of viruses which is critical to the inter-species transmission. Angiotensin-converting enzyme 2 (ACE2) is the receptor of both SARS-CoV and SARS-CoV-2, but only ACE2s of certain animals can be utilized by the viruses. Here, we employed pseudovirus cell-entry assay to evaluate the receptor-utilizing capability of ACE2s of 20 animals by the two viruses and found that SARS-CoV-2 utilized less ACE2s than SARS-CoV, indicating a narrower host range of SARS-CoV-2. Especially, SARS-CoV-2 tended not to use murine or non-mammal ACE2s. Meanwhile, pangolin-CoV, another SARS-related coronavirus highly homologous to SARS-CoV-2 in its genome, yet showed similar ACE2 utilization profile with SARS-CoV rather than SARS-CoV-2. Nevertheless, the actual susceptibility of these animals to the coronaviruses should be further verified by in vivo studies. To clarify the mechanism underlying the receptor utilization, we compared the amino acid sequences of the 20 ACE2s and found 5 amino acid residues potentially critical for ACE2 utilization, including the N-terminal 20th and 42nd amino acid residues that might determine the different receptor utilization of SARS-CoV, SARS-CoV-2 and pangolin-CoV. Our studies enhance the understanding of receptor utilization of pandemic coronaviruses, potentially contributing to the virus tracing, intermediate host screening and epidemic prevention for pathogenic coronaviruses.

5.
Microbes Infect ; 22(4-5): 221-225, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32199943

RESUMO

SARS-CoV-2, the newly identified human coronavirus causing severe pneumonia pandemic, was probably originated from Chinese horseshoe bats. However, direct transmission of the virus from bats to humans is unlikely due to lack of direct contact, implying the existence of unknown intermediate hosts. Angiotensin converting enzyme 2 (ACE2) is the receptor of SARS-CoV-2, but only ACE2s of certain species can be utilized by SARS-CoV-2. Here, we evaluated and ranked the receptor-utilizing capability of ACE2s from various species by phylogenetic clustering and sequence alignment with the currently known ACE2s utilized by SARS-CoV-2. As a result, we predicted that SARS-CoV-2 tends to utilize ACE2s of various mammals, except murines, and some birds, such as pigeon. This prediction may help to screen the intermediate hosts of SARS-CoV-2.


Assuntos
Betacoronavirus/metabolismo , Aves/metabolismo , Infecções por Coronavirus/virologia , Mamíferos/metabolismo , Peptidil Dipeptidase A/genética , Pneumonia Viral/virologia , Sequência de Aminoácidos , Animais , Humanos , Pandemias , Filogenia , Conformação Proteica , Especificidade da Espécie
6.
Microbes Infect ; 22(2): 80-85, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32087334

RESUMO

At the end of December 2019, a novel coronavirus, 2019-nCoV, caused an outbreak of pneumonia spreading from Wuhan, Hubei province, to the whole country of China, which has posed great threats to public health and attracted enormous attention around the world. To date, there are no clinically approved vaccines or antiviral drugs available for these human coronavirus infections. Intensive research on the novel emerging human infectious coronaviruses is urgently needed to elucidate their route of transmission and pathogenic mechanisms, and to identify potential drug targets, which would promote the development of effective preventive and therapeutic countermeasures. Herein, we describe the epidemic and etiological characteristics of 2019-nCoV, discuss its essential biological features, including tropism and receptor usage, summarize approaches for disease prevention and treatment, and speculate on the transmission route of 2019-nCoV.


Assuntos
Betacoronavirus/patogenicidade , Doenças Transmissíveis Emergentes/epidemiologia , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Antivirais/uso terapêutico , Betacoronavirus/genética , China/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Epidemias , Genoma Viral , Humanos , Filogenia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Pneumonia Viral/transmissão , Receptores Virais , Tropismo Viral
8.
J Anesth ; 32(1): 77-81, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29164334

RESUMO

PURPOSE: Preoperative sleep study helps to predict post-adenotonsillectomy morphine requirements. However, in some institutions, many suspected children with obstructive sleep apnoea syndrome have an adenotonsillectomy without polysomnography assessments. This study investigated the relationship between the results of a fentanyl test performed before extubation and the postoperative morphine requirements in children after adenotonsillectomy. METHODS: Intravenous fentanyl (1 µg/kg) was given as a test before extubation when spontaneous ventilation was restored in 80 children aged 3-7 years who underwent adenotonsillectomy. The result was considered positive if the patient's respiratory rate decreased >50% after the test. In the recovery room, pain was assessed every 10 min using the Children's Hospital of Eastern Ontario Pain Scale. Rescue morphine (10 µg/kg) was given when the score was ≥6. RESULTS: The median [IQR (range)] cumulative morphine consumption rates for children with a positive result (n = 25) and a negative result (n = 52) were 30 (20, 40) and 50 (40, 50) µg/kg, respectively (P = 0.002). Eighty-eight percent of the positive-result patients and 48% of the negative-result patients were light consumers of morphine (cumulative dose <50 µg/kg) (P = 0.001). CONCLUSIONS: We conclude that children with a positive result after a fentanyl test require less morphine to achieve comfort than those with a negative result. CLINICALTRIALS. GOV ID: NCT02484222.


Assuntos
Adenoidectomia/métodos , Fentanila/administração & dosagem , Morfina/administração & dosagem , Tonsilectomia/métodos , Extubação , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Medição da Dor , Polissonografia , Período Pós-Operatório , Apneia Obstrutiva do Sono/complicações
9.
Paediatr Anaesth ; 23(4): 322-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23072260

RESUMO

BACKGROUND: Acceleromyography used to monitor the neuromuscular transmission function is available in infants and children. However, information on the so-called staircase phenomenon during the baseline stabilization period in this population is limited. Our objective was to assess the characteristics of such phenomenon in infants in acceleromyography. METHODS: Thirty infants were divided into three groups: group A (aged 1-5 months, n = 10), group B (aged 6-11 months, n = 10), and group C (aged 12-24 months, n = 10). Anesthesia was induced and maintained without neuromuscular blocking agents. Patients received a supramaximal stimulus followed by TOF measurements every 15 s over the course of 30 min with a TOF-Watch(®) SX. All data were collected in a notebook computer using the TOF-Watch(®) SX Monitor software through optical fibers. RESULTS: The evoked T1 responses in younger infants (group A) were significantly lower than those in older infants (groups B and C) from 0-20 min. In group A, the signals increased to the maximum value of 121 ± 15% that of the control at 7.25 min and decreased toward a plateau of 113 ± 18% at 30 min. In group B, the signal heights increased to the maximum value of 143 ± 14% at 9.5 min, then decreased slowly to 136 ± 10% at 19.5 min, finally reaching 116 ± 12% at 30 min. In group C, the mean values of T1 reached the maximum of 139 ± 19% that of control at 9.5 min and finally reached 126 ± 22% of control at 30 min. CONCLUSIONS: The staircase effect presents in a shorter time course and at lower degrees in smaller infants. However, in older infants, staircase effect still presents in a long period and may influence the onset time and duration of twitch depression after muscle relaxants administration.


Assuntos
Anestesia , Monitorização Intraoperatória/estatística & dados numéricos , Miografia/métodos , Análise de Variância , Anestesia Geral , Anestesia por Inalação , Anestesia Intravenosa , Anestésicos Inalatórios , Anestésicos Intravenosos , Peso Corporal/fisiologia , Estimulação Elétrica , Feminino , Humanos , Lactente , Masculino , Monitorização Intraoperatória/métodos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Óxido Nitroso , Piperidinas , Propofol , Remifentanil , Transmissão Sináptica/efeitos dos fármacos
10.
Ann Hematol ; 91(4): 553-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21987025

RESUMO

MicroRNAs (miRNAs) are regulatory RNA molecules that are deregulated in many disease types, including cancer. Recently, miRNAs have shown promise as markers for cancer diagnosis. The aim of this study was to investigate whether serum miRNAs can be used as biomarkers for the detection of diffuse large B cell lymphoma (DLBCL). We measured the levels of miRNAs (miR-15a, miR-16-1, miR-21, miR-29c, miR-34a, miR-155, and miR-223) in serum samples from patients with DLBCL and healthy controls using real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR). We show here that miRNAs are present in human serum in a remarkably stable form. Four of miRNAs (miR-15a, miR-16-1, miR-29c, and miR-155) were significantly elevated in DLBCL serum when compared with normal controls (P < 0.05), while miR-34a was downregulated in DLBCL serum when compared with controls (P < 0.05). Receiver operating characteristic analyses reflects strong discriminating DLBCL from controls, with area under the curves of 0.7722, 0.7002, 0.6672, 0.8538, and 0.7157 for miR-15a, miR-16-1, miR-29c, miR-34a, and miR-155, respectively. At the cut-off value of 0.0006 for miR-15a, the sensitivity was 80% and the specificity was 76%; at the cut-off value of 0.0886 for miR-16-1, the sensitivity was 94% and the specificity was 51%; at the cut-off value of 1.395 for miR-34a, the sensitivity was 100% and the specificity was 70%; at the cut-off value of 0.0022 for miR-155, the sensitivity was 83% and the specificity was 65%. In conclusion, these data suggest that serum miRNAs are potentially useful tools as novel noninvasive biomarker for the diagnosis of DLBCL.


Assuntos
Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Linfoma Difuso de Grandes Células B/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Curva ROC , Adulto Jovem
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