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In recent years, the rapid development of sensors and information technology has made it possible for machines to recognize and analyze human emotions. Emotion recognition is an important research direction in various fields. Human emotions have many manifestations. Therefore, emotion recognition can be realized by analyzing facial expressions, speech, behavior, or physiological signals. These signals are collected by different sensors. Correct recognition of human emotions can promote the development of affective computing. Most existing emotion recognition surveys only focus on a single sensor. Therefore, it is more important to compare different sensors or unimodality and multimodality. In this survey, we collect and review more than 200 papers on emotion recognition by literature research methods. We categorize these papers according to different innovations. These articles mainly focus on the methods and datasets used for emotion recognition with different sensors. This survey also provides application examples and developments in emotion recognition. Furthermore, this survey compares the advantages and disadvantages of different sensors for emotion recognition. The proposed survey can help researchers gain a better understanding of existing emotion recognition systems, thus facilitating the selection of suitable sensors, algorithms, and datasets.
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Algoritmos , Emoções , Humanos , Emoções/fisiologia , Reconhecimento Psicológico , Expressão Facial , FalaRESUMO
Accurately detecting falls and providing clear directions for the fall can greatly assist medical staff in promptly developing rescue plans and reducing secondary injuries during transportation to the hospital. In order to facilitate portability and protect people's privacy, this paper presents a novel method for detecting fall direction during motion using the FMCW radar. We analyze the fall direction in motion based on the correlation between different motion states. The range-time (RT) features and Doppler-time (DT) features of the person from the motion state to the fallen state were obtained by using the FMCW radar. We analyzed the different features of the two states and used a two-branch convolutional neural network (CNN) to detect the falling direction of the person. In order to improve the reliability of the model, this paper presents a pattern feature extraction (PFE) algorithm that effectively eliminates noise and outliers in RT maps and DT maps. The experimental results show that the method proposed in this paper has an identification accuracy of 96.27% for different falling directions, which can accurately identify the falling direction and improve the efficiency of rescue.
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Algoritmos , Radar , Humanos , Reprodutibilidade dos Testes , Redes Neurais de ComputaçãoRESUMO
The multiple nomenclature systems of SARS-CoV-2 are confusing and have several issues. The emergence of variants of concern and variants of interest has posed an increased risk to global health. To assist with public discussion and communication with nonscientific audiences about significant mutations, and ultimately to inform the ongoing response to the COVID-19 pandemic, we scientists need to develop easy-to-pronounce and nonstigmatizing labels for significant mutations.
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COVID-19 , SARS-CoV-2 , Saúde Global , Humanos , Mutação , Pandemias , SARS-CoV-2/genéticaRESUMO
The Omicron SARS-CoV-2 variant was potentially generated from a chronically infected COVID-19 patient vaccinated with an messenger RNA (mRNA)- or non-mRNA-based vaccine, offering the opportunity for the virus to evolve and mutate to evade the body's immune response. To understand the significance of this SARS-CoV-2 variant and what it means for the global response to the pandemic, vaccinologists should systematically evaluate the role of mRNA- and non-mRNA-based vaccines in the generation of novel SARS-CoV-2 variants, including variants of concerns (VOCs) and interest (VOIs), that occur via breakthrough vaccine-elicited immunity. Although COVID vaccine boosters are likely to offer some protection and mRNA- or non-mRNA-based vaccines can be adapted to new variants, such as Omicron, the requirement of a booster so soon after full vaccination, with further shots potentially required, is of concern given the impacts on human health. Therefore, in the race to protect the global population against novel SARS-CoV-2 VOCs and VOIs, there is an urgent need to create much more effective one-dose vaccines that can protect people over their entire lifetime.
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COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Desenvolvimento de Vacinas , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Humanos , Evasão da Resposta Imune , Imunização Secundária , Hospedeiro Imunocomprometido , Ligação Proteica , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
The presence of apoptosis inhibition proteins renders the cancer cells resistant to apoptosis, severely compromising the antitumor efficacy of sonodynamic therapy (SDT). Here, an intelligent anticancer nanoplatform based on an Aza-boron-dipyrromethene dye (denoted as Aza-BDY) is elaborately established for ferroptosis augmented SDT through cysteine (Cys) starvation. After endocytosis by tumor cells, Aza-BDY serves as both a ferroptosis inducing agent and a sonosensitizer for tumor treatment. The specific Cys response facilitates the disruption of redox homeostasis and initiation of cellular ferroptosis. Meanwhile, the released sonosensitizer causes efficient SDT and augments ferroptosis under ultrasound irradiation. Detailed in vitro and in vivo investigations demonstrate that the synergistic effect of Cys depletion and singlet oxygen (1 O2 ) generation significantly induces cancer-cell death and suppresses tumor proliferation with a high inhibition rate of 97.5 %.
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Ferroptose , Nanopartículas , Neoplasias , Boro , Linhagem Celular Tumoral , Cisteína , Humanos , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Porfobilinogênio/análogos & derivados , Espécies Reativas de Oxigênio/metabolismo , Oxigênio Singlete/metabolismoRESUMO
Apart from the traditional through-bond conjugation (TBC), through-space conjugation (TSC) is gradually proved as another important interaction in photophysical processes, especially for the recent observation of clusteroluminescence from nonconjugated molecules. However, unlike TBC in conjugated chromophores, it is still challenging to manipulate TSC and clusteroluminescence. Herein, simple and nonconjugated triphenylmethane (TPM) and its derivatives with electron-donating and electron-withdrawing groups were synthesized, and their photophysical properties were systematically studied. TPM was characterized with visible clusteroluminescence due to the intramolecular TSC. Experimental and theoretical results showed that the introduction of electron-donating groups into TPM could red-shift the wavelength and increase the efficiency of clusteroluminescence simultaneously, due to the increased electronic density and stabilization of TSC. However, TPM derivatives with electron-withdrawing groups showed inefficient or even quenched clusteroluminescence caused by the vigorous excited-state intramolecular motion and intermolecular photoinduced electron transfer process. This work provides a reliable strategy to manipulate TSC and clusteroluminescence.
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The HIV epidemic in China accounts for 3% of the global HIV incidence. We compared the patterns and determinants of interprovincial spread of the five most prevalent circulating types. HIV pol sequences sampled across China were used to identify relevant transmission networks of the five most relevant HIV-1 types (B and circulating recombinant forms [CRFs] CRF01_AE, CRF07_BC, CRF08_BC, and CRF55_01B) in China. From these, the dispersal history across provinces was inferred. A generalized linear model (GLM) was used to test the association between migration rates among provinces and several measures of human mobility. A total of 10,707 sequences were collected between 2004 and 2017 across 26 provinces, among which 1,962 are newly reported here. A mean of 18 (minimum and maximum, 1 and 54) independent transmission networks involving up to 17 provinces were identified. Discrete phylogeographic analysis largely recapitulates the documented spread of the HIV types, which in turn, mirrors within-China population migration flows to a large extent. In line with the different spatiotemporal spread dynamics, the identified drivers thereof were also heterogeneous but are consistent with a central role of human mobility. The comparative analysis of the dispersal dynamics of the five main HIV types circulating in China suggests a key role of large population centers and developed transportation infrastructures as hubs of HIV dispersal. This advocates for coordinated public health efforts in addition to local targeted interventions.IMPORTANCE While traditional epidemiological studies are of great interest in describing the dynamics of epidemics, they struggle to fully capture the geospatial dynamics and factors driving the dispersal of pathogens like HIV as they have difficulties capturing linkages between infections. To overcome this, we used a discrete phylogeographic approach coupled to a generalized linear model extension to characterize the dynamics and drivers of the across-province spread of the five main HIV types circulating in China. Our results indicate that large urbanized areas with dense populations and developed transportation infrastructures are facilitators of HIV dispersal throughout China and highlight the need to consider harmonized country-wide public policies to control local HIV epidemics.
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Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , China/epidemiologia , Genótipo , Infecções por HIV/transmissão , HIV-1/genética , Humanos , Epidemiologia Molecular , Filogenia , Filogeografia , Saúde PúblicaRESUMO
BACKGROUND: In China, an HIV-infected man (complainant; P2) alleged that another man (defendant; P1) had unlawfully infected him with HIV through unprotected homosexual contact in 2018. METHODS: We employed epidemiological, serological and phylogenetic analyses to investigate the transmission linkage between two men who have sex with men (MSM). Partial segments of three HIV-1 gene regions (gag, pol, and env) were amplified and sequenced by cloning. Maximum-likelihood (ML) and Bayesian methods were used to determine the direction and estimate the timing of transmission. Local control sequences and database control sequences were also used in the phylogenetic analysis. RESULTS: It indicated that P2 underwent HIV seroconversion after P1 was diagnosed as HIV positive. The time to the most recent common ancestor (tMRCA) estimates consistently showed that P1 most likely became HIV-1 infected at an earlier date than P2. P1 and P2 were infected with the same HIV-1 CRF01_AE subtype according to segments of all three gene regions (gag, pol, and env). All three genetic regions of P1 have been subject to more potential selective forces than those of P2, indicating a longer evolutionary history. Bayesian and ML trees showed similar paraphyletic-monophyletic topologies of gag and env, with the virus from P1 located at the root, which supported a P1-to-P2 transmission direction. CONCLUSIONS: Phylogenetic investigations can elucidate HIV transmission linkage and might empower its use in the opposition of the intentional transmission of HIV-1 as a forensic tool.
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Infecções por HIV , Soropositividade para HIV , HIV-1 , Minorias Sexuais e de Gênero , Teorema de Bayes , Infecções por HIV/transmissão , HIV-1/genética , Homossexualidade Masculina , Humanos , Masculino , FilogeniaRESUMO
To investigate the genetic diversity, time origin, and evolutionary history of the 2019-nCoV outbreak in China and Thailand, a total of 12 genome sequences of the virus with known sampling date (24 December 2019 and 13 January 2020) and geographic location (primarily Wuhan city, Hubei Province, China, but also Bangkok, Thailand) were analyzed. Phylogenetic and likelihood-mapping analyses of these genome sequences were performed. On the basis of our results, the star-like signal and topology of 2019-nCoV may be indicative of potentially large "first generation" human-to-human virus transmission. We estimated that 2019-nCoV likely originated in Wuhan on 9 November 2019 (95% credible interval: 25 September 2019 and 19 December 2019), and that Wuhan is the major hub for the spread of the 2019-nCoV outbreak in China and elsewhere. Our results could be useful for designing effective prevention strategies for 2019-nCoV in China and beyond.
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Quirópteros , Coronavirus , Pneumonia , Animais , Betacoronavirus , China , Surtos de Doenças , Humanos , Filogenia , SARS-CoV-2 , TailândiaRESUMO
The current outbreak of viral pneumonia in the city of Wuhan, China, was caused by a novel coronavirus designated 2019-nCoV by the World Health Organization, as determined by sequencing the viral RNA genome. Many initial patients were exposed to wildlife animals at the Huanan seafood wholesale market, where poultry, snake, bats, and other farm animals were also sold. To investigate possible virus reservoir, we have carried out comprehensive sequence analysis and comparison in conjunction with relative synonymous codon usage (RSCU) bias among different animal species based on the 2019-nCoV sequence. Results obtained from our analyses suggest that the 2019-nCoV may appear to be a recombinant virus between the bat coronavirus and an origin-unknown coronavirus. The recombination may occurred within the viral spike glycoprotein, which recognizes a cell surface receptor. Additionally, our findings suggest that 2019-nCoV has most similar genetic information with bat coronovirus and most similar codon usage bias with snake. Taken together, our results suggest that homologous recombination may occur and contribute to the 2019-nCoV cross-species transmission.
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Betacoronavirus/genética , Quirópteros/virologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Reservatórios de Doenças , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Serpentes/virologia , Glicoproteína da Espícula de Coronavírus/genética , Animais , Betacoronavirus/classificação , Betacoronavirus/fisiologia , Bungarus/genética , Bungarus/virologia , COVID-19 , Quirópteros/genética , Uso do Códon , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Evolução Molecular , Genoma Viral , Recombinação Homóloga , Especificidade de Hospedeiro , Humanos , Naja naja/genética , Naja naja/virologia , Filogenia , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Serpentes/genética , ZoonosesRESUMO
To investigate the time origin, genetic diversity, and transmission dynamics of the recent 2019-nCoV outbreak in China and beyond, a total of 32 genomes of virus strains sampled from China, Thailand, and the USA with sampling dates between 24 December 2019 and 23 January 2020 were analyzed. Phylogenetic, transmission network, and likelihood-mapping analyses of the genome sequences were performed. On the basis of the likelihood-mapping analysis, the increasing tree-like signals (from 0% to 8.2%, 18.2%, and 25.4%) over time may be indicative of increasing genetic diversity of 2019-nCoV in human hosts. We identified three phylogenetic clusters using the Bayesian inference framework and three transmission clusters using transmission network analysis, with only one cluster identified by both methods using the above genome sequences of 2019-nCoV strains. The estimated mean evolutionary rate for 2019-nCoV ranged from 1.7926 × 10-3 to 1.8266 × 10-3 substitutions per site per year. On the basis of our study, undertaking epidemiological investigations and genomic data surveillance could positively impact public health in terms of guiding prevention efforts to reduce 2019-nCOV transmission in real-time.
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Betacoronavirus/genética , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Genoma Viral , Pneumonia Viral/transmissão , Teorema de Bayes , COVID-19 , China , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Humanos , Funções Verossimilhança , Modelos Genéticos , Taxa de Mutação , Filogenia , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Tailândia , Estados UnidosRESUMO
To investigate the evolutionary history of the recent outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China, a total of 70 genomes of virus strains from China and elsewhere with sampling dates between 24 December 2019 and 3 February 2020 were analyzed. To explore the potential intermediate animal host of the SARS-CoV-2 virus, we reanalyzed virome data sets from pangolins and representative SARS-related coronaviruses isolates from bats, with particular attention paid to the spike glycoprotein gene. We performed phylogenetic, split network, transmission network, likelihood-mapping, and comparative analyses of the genomes. Based on Bayesian time-scaled phylogenetic analysis using the tip-dating method, we estimated the time to the most recent common ancestor and evolutionary rate of SARS-CoV-2, which ranged from 22 to 24 November 2019 and 1.19 to 1.31 × 10-3 substitutions per site per year, respectively. Our results also revealed that the BetaCoV/bat/Yunnan/RaTG13/2013 virus was more similar to the SARS-CoV-2 virus than the coronavirus obtained from the two pangolin samples (SRR10168377 and SRR10168378). We also identified a unique peptide (PRRA) insertion in the human SARS-CoV-2 virus, which may be involved in the proteolytic cleavage of the spike protein by cellular proteases, and thus could impact host range and transmissibility. Interestingly, the coronavirus carried by pangolins did not have the RRAR motif. Therefore, we concluded that the human SARS-CoV-2 virus, which is responsible for the recent outbreak of COVID-19, did not come directly from pangolins.
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Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Genoma Viral , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Glicoproteína da Espícula de Coronavírus/genética , Sequência de Aminoácidos , Animais , Betacoronavirus/classificação , Betacoronavirus/patogenicidade , COVID-19 , Quirópteros/virologia , Infecções por Coronavirus/virologia , Eutérios/virologia , Evolução Molecular , Especificidade de Hospedeiro , Humanos , Filogenia , Pneumonia Viral/virologia , SARS-CoV-2 , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Glicoproteína da Espícula de Coronavírus/classificação , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
An organocatalytic enantioconvergent synthesis of chiral tetrasubstituted allenes is disclosed. With suitable chiral phosphoric acid catalysts, a range of racemic indole-substituted propargylic alcohols reacted with nucleophiles to provide efficient access to a series of enantioenriched allenes with high enantioselectivities. Control experiments suggested a mechanism involving remotely controlled asymmetric 1,8-addition of the in situ generated indole imine methide via a bifunctional transition state.
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By using biphenyl-2-ylphosphines functionalized with a remote tertiary amino group as a ligand, readily available acetylenic amides are directly converted into 2-aminofurans devoid of any electron-withdrawing and hence deactivating/stabilizing substituents. These highly electron-rich furans have rarely been prepared, let alone applied in synthesis, because of their high reactivities and low stabilities associated with the electron-rich nature of the furan ring. In this work, these reactive furans smoothly undergo either in situ intermolecular Diels-Alder reactions to deliver highly functionalized/substituted aniline products or intramolecular ones to furnish carbazole-4-carboxylates in mostly good to excellent yields. This work offers general and expedient access to this class of little studies electron-rich furans and should lead to exciting opportunities for their applications.
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To investigate the codon usage patterns of all available VP1 gene sequences of the GII.2 genotype, to determine the factors that affect these patterns, and to provide comprehensive details of the characteristics and evolution of the gene. Complete 519 sequences of VP1 gene of the HuNoV GII.2 genotype with known sampling dates and geographic locations from 1971 - 2017 were retrieved from the GenBank nucleotide database of the National Center for Biotechnology Information (NCBI) and analyzed. The percentage composition of T, C, A, and G nucleotides were 24.80 ± 0.30, 26.61 ± 0.31, 25.84 ± 0.13, and 22.75 ± 0.17 %, respectively, with C and A relatively more abundant than T and G, and C the most abundant (p < 0.0001). The values of T3s (34.10 ± 0.90 %) and C3s (33.54 ± 0.90 %) were significantly higher than those of A3s (29.98 ± 0.43 %) and G3s (24.13 ± 0.51 %) (p < 0.0001). While T3s was highest among the four nucleotides, G3s was the lowest. Among the 18 most frequently employed synonymous codons, six optional codons ended with T, five ended with C, five ended with A and two ended with G. Codons ending with T were the most frequently used. The ENC ranged from 51.90 to 54.25 (mean = 52.38 ± 0.43) among the 519 VP1 gene sequences. There were significant correlations between ENC and C % and G % (p < 0.01). Codons containing CpG (1 and 2 or 2 and 3 codon positions) showed the lowest frequencies, while 30, 29, and 2 codons were above, below and on the mean line, respectively. The first four principal components accounted for 69.11 % of the total variation, with the first, second, third, and fourth principal axes contributing 37.90, 14.83, 9.61, and 6.77 %, respectively. The strains were not clustered by country of isolation or year of sampling. Gravy were significantly correlated with T3s, C3s, G3s, GC3s, and ENC (p < 0.01). Mutation pressure and natural selection contributed to the codon usage bias of the VP1 gene of the HuNoV GII.2 genotype. There was a correlation between GC12s and GC3s (R2 = 0.032; p < 0.0001). The relative neutrality was 3.20 %, while natural selection was 96.80 %. The VP1 gene exhibits low codon usage bias which is affected primarily by natural selection, followed by mutation pressure and translational selection.
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Proteínas do Capsídeo/genética , Códon/genética , Genes Virais , Norovirus/genética , Composição de Bases/genética , Genótipo , Humanos , Mutação/genética , Análise de Componente Principal , Seleção GenéticaRESUMO
Epithelial-mesenchymal transition (EMT) is a developmental program, which is associated with hepatocellular carcinoma (HCC) development and progression. DNAJC6 (DNA/HSP40 homolog subfamily C member 6) encodes auxilin, which is responsible for juvenile Parkinsonism with phenotypic variability. However, the role of DNAJC6 in HCC development and progression is limited. Here, we report that DNAJC6 is up-regulated in HCC tissues and up-regulation of DNAJC6 expression predicts poor outcome in patients with HCC. Furthermore, overexpression of DNAJC6 enhances the ability for acquisition of mesenchymal traits, enhanced cell proliferation and invasion. DNAJC6 positively regulated expression of EMT-related transcription factor, also activating transforming growth factor ß (TGF-ß) pathway to contribute to EMT. Our findings demonstrated an important function of DNAJC6 in the progression of HCC by induction of EMT, and they implicate DNAJC6 as a marker of poor outcome in HCC.
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Carcinoma Hepatocelular/metabolismo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP40/fisiologia , Neoplasias Hepáticas/metabolismo , Idoso , Animais , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Proteínas de Choque Térmico HSP40/genética , Humanos , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Fator de Crescimento Transformador beta/metabolismo , Resultado do Tratamento , Regulação para CimaRESUMO
OBJECTIVE: To explore the effect of Tongluojiunao injection (TLJN) prepared with Sanqi (Radix Notoginseng) and Zhizi (Fructus Gardeniae) on the interaction between brain microvascular endothelial cells (BMECs) and astrocytes in an in vitro ischemic model. METHODS: First, an in vitro model of cerebral ischemia in BMECs or astrocytes was established by oxygen-glucose deprivation (OGD). TLJN was used as a medicine of intervention. The OGD-injured BMECs were cultured in various astrocyte-conditioned media. Cell activity, alkaline phosphatase (AKP) and γ-glutamyl transpeptidase (γ-GT) activity, interleukin-1 beta (IL-1ß), and tumor necrosis factor alpha (TNF-α) content in BMECs were determined. Additionally, OGD-injured astrocytes were cultured in various BMEC-conditioned media. Cell activity, as well as expression of brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) in astrocytes, were detected. RESULTS: The results of paracrine signaling of normal BMECs or astrocytes showed a protective effect on each other: conditioned media from normal astrocytes improved cell viability, AKP, and γ-GT activity, and reduced IL-1ß and TNF-α content of injured BMECs; conditioned media from normal BMECs improved cell viability and expression of BDNF and GDNF in injured astrocytes. However, once the BMECs or astrocytes were injured by OGD, the protective effect decreased or disappeared. The above-mentioned protective induction was effectively recovered by TLJN intervention. CONCLUSION: The therapeutic benefit of TLJN was achieved by recovering two-way induction between BMECs and astrocytes, enhancing activity of injured BMECs and astrocytes, stabilizing enzymatic barriers, promoting expression of neurotrophic factors, and inhibiting inflammatory cytokines.
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Astrócitos/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Células Endoteliais/efeitos dos fármacos , Gardenia/química , Panax notoginseng/química , Animais , Astrócitos/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Humanos , Interleucina-1beta/metabolismo , Masculino , Microvasos/citologia , Microvasos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Introduction. Human immunodeficiency virus (HIV)-1 subtype C is the most prevalent globally and is thought to have originated in non-human primates in the Democratic Republic of Congo.Hypothesis/Gap Statement. Although the global dominance of HIV-1 subtype C is well established, a thorough understanding of its evolutionary history and transmission dynamics across various risk populations remains elusive. The current knowledge is insufficient to fully capture the global diversification and dissemination of this subtype.Aim. We for the first time sought to investigate the global evolutionary history and spatiotemporal dynamics of HIV-1 subtype C using a selection of maximum-likelihood-based phylodynamic approaches on a total of 1210 near full-length genomic sequences sampled from 32 countries, collected in 4 continents, with sampling dates between 1986-2019 among various risk groups were analysed.Methodology. We subsampled the HIV-1 subtype C genomic datasets based on continent and risk group traits, and performed nucleotide substitution model selection analysis, maximum likelihood (ML) phylogenetic reconstruction, phylogenetic tree topology similarity analysis, temporal signal analysis and traced the timings of viral spread both geographically and by risk group.Results. Based on the phylodynamic analyses of four datasets (full1210, locrisk626, loc562 and risk393), we inferred the time to the most recent common ancestor (TMRCA) in the 1930s and an evolutionary rate of 0.0023 substitutions per site per year. The total number of introduction events of HIV-1 subtype C between continents and between risk groups is estimated to be 71 and 115, respectively. The largest number of introductions occurred from Africa to Europe (n=32), from not-recorded to heterosexual (n=40) and from heterosexual to not-recorded (n=51) risk groups.Conclusion. Our results emphasize that HIV subtype C has mainly spread from Africa to Europe, likely through heterosexual transmission.
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Infecções por HIV , HIV-1 , Filogenia , HIV-1/genética , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Infecções por HIV/virologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Evolução MolecularRESUMO
We present an iridium and Brønsted acid co-catalyzed enantioselective formal [4+2] cycloaddition reaction of cyclic enamides with 2-(1-hydroxyallyl)phenols. This method yields a wide range of N-unsubstituted spiro-N,O-ketals, with good efficiency (up to 94%) and excellent enantioselectivities (most >95% ee). The protocol features easy scale-up and facile product derivatization.