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1.
mSphere ; 6(1)2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568452

RESUMO

Compared to other human coronaviruses, the genetic diversity and evolution of human coronavirus 229E (HCoV-229E) are relatively understudied. We report a fatal case of COVID-19 pneumonia coinfected with HCoV-229E in Hong Kong. Genome sequencing of SARS-CoV-2 and HCoV-229E from a nasopharyngeal sample of the patient showed that the SARS-CoV-2 strain HK13 was most closely related to SARS-CoV-2 type strain Wuhan-Hu-1 (99.99% nucleotide identity), compatible with his recent history of travel to Wuhan. The HCoV-229E strain HK20-42 was most closely related to HCoV-229E strain SC0865 from the United States (99.86% nucleotide identity). To investigate if it may represent a newly emerged HCoV-229E genotype in Hong Kong, we retrieved 41 archived respiratory samples that tested positive for HCoV-229E from 2004 to 2019. Pneumonia and exacerbations of chronic airway diseases were common among infected patients. Complete RdRp, S, and N gene sequencing of the 41 HCoV-229E strains revealed that our contemporary HCoV-229E strains have undergone significant genetic drift with clustering of strains in chronological order. Two novel genogroups were identified, in addition to previously described genogroups 1 to 4, with recent circulating strains including strain HK20-42 belonging to novel genogroup 6. Positive selection was detected in the spike protein and receptor-binding domain, which may be important for viral evolution at the receptor-binding interphase. Molecular dating analysis showed that HCoV-229E shared the most recent common ancestor with bat and camel/alpaca 229E-related viruses at ∼1884, while camel/alpaca viruses had a relatively recent common ancestor at ∼1999. Further studies are required to ascertain the evolutionary origin and path of HCoV-229E.IMPORTANCE Since its first appearance in the 1960s, the genetic diversity and evolution of human coronavirus 229E (HCoV-229E) have been relatively understudied. In this study, we report a fatal case of COVID-19 coinfected with HCoV-229E in Hong Kong. Genome sequencing revealed that our SARS-CoV-2 strain is highly identical to the SARS-CoV-2 strain from Wuhan, compatible with the patient's recent travel history, whereas our HCoV-229E strain in this study is highly identical to a recent strain in the United States. We also retrieved 41 archived HCoV-229E strains from 2004 to 2019 in Hong Kong for sequence analysis. Pneumonia and exacerbations of chronic airway diseases were common diagnoses among the 41 patients. The results showed that HCoV-229E was evolving in chronological order. Two novel genogroups were identified in addition to the four preexisting HCoV-229E genogroups, with recent circulating strains belonging to novel genogroup 6. Molecular clock analysis dated bat-to-human and bat-to-camelid transmission to as early as 1884.


Assuntos
COVID-19/patologia , Resfriado Comum/patologia , Coronavirus Humano 229E/genética , Variação Genética/genética , SARS-CoV-2/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , COVID-19/mortalidade , Criança , Pré-Escolar , Coinfecção/virologia , Evolução Molecular , Feminino , Genoma Viral/genética , Hong Kong , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Domínios Proteicos/genética , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/genética , Adulto Jovem
2.
Mycoses ; 63(12): 1283-1298, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32918365

RESUMO

BACKGROUND: The number of patients infected with Aspergillus rose dramatically in recent years. However, studies on the clinical spectrum and antifungal susceptibilities of non-classical (non-fumigatus, non-flavus, non-niger and non-terreus) pathogenic Aspergillus species are very limited. OBJECTIVES: We examined the clinical spectrum and antifungal susceptibilities of 34 non-duplicated, non-classical Aspergillus isolates collected from Hong Kong, Shenzhen and Shanghai. METHODS: The Aspergillus isolates were identified by internal transcribed spacer, partial BenA and partial CaM sequencing and phylogenetic analyses. Susceptibility testing against eight antifungals was performed following the European Committee for Antimicrobial Susceptibility Testing's methodology. RESULTS: The 34 Aspergillus isolates were identified as 14 different rare/cryptic species of four sections (Flavi [n = 8], Nidulantes [n = 8], Nigri [n = 17] and Restricti [n = 1]). Except for one patient whose clinical history could not be retrieved, 72.7% of the remaining patients had underlying conditions predisposing them to Aspergillus infections. The most common diseases were pulmonary infections (n = 15), followed by skin/nail infections (n = 6), chronic otitis externa and/or media (n = 5), wound infections (n = 2) and mastoiditis/radionecrosis (n = 1), while three were colonisations. Five patients succumbed due to the infections during the admission, and another two died 5 years later because of chronic pulmonary aspergillosis. Antifungal susceptibility testing showed that they possessed different susceptibility profiles compared to the classical Aspergillus species. The majority of isolates characterised were sensitive or wild-type to amphotericin B. The minimum effective concentrations for all the three echinocandins were also low. CONCLUSION: Susceptibility testing should be performed for infections due to these rare/cryptic Aspergillus species to guide proper patient management.


Assuntos
Antifúngicos/farmacologia , Aspergillus/classificação , Aspergillus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/uso terapêutico , Aspergilose/complicações , Aspergilose/tratamento farmacológico , Pré-Escolar , China , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
3.
Emerg Microbes Infect ; 8(1): 531-541, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30938262

RESUMO

Onychomycosis is most commonly caused by dermatophytes. In this study, we examined the spectrum of phenotypically non-dermatophyte and non-Aspergillus fungal isolates recovered over a 10-year period from nails of patients with onychomycosis in Hong Kong. A total of 24 non-duplicated isolates recovered from 24 patients were included. The median age of the patients was 51 years, and two-thirds of them were males. One-third and two-thirds had finger and toe nail infections respectively. Among these 24 nail isolates, 17 were confidently identified as 13 different known fungal species, using a polyphasic approach. These 13 species belonged to 11 genera and ≥9 families. For the remaining seven isolates, multilocus sequencing did not reveal their definite species identities. These seven potentially novel species belonged to four different known and three potentially novel genera of seven families. 33.3%, 41.7% and 95.8% of the 24 fungal isolates possessed minimum inhibitory concentrations of >1 µg/mL to terbinafine, itraconazole and fluconazole, respectively, the first line treatment of onychomycosis. A high diversity of moulds was associated with onychomycosis. A significant proportion of the isolates were potentially novel fungal species. To guide proper treatment, molecular identification and antifungal susceptibility testing should be performed for these uncommonly isolated fungal species.


Assuntos
Antifúngicos/farmacologia , Biodiversidade , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação , Doenças da Unha/microbiologia , Onicomicose/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Fluconazol/farmacologia , Fungos/classificação , Fungos/genética , Hong Kong , Humanos , Itraconazol/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Onicomicose/microbiologia , Fenótipo , Filogenia , Terbinafina/farmacologia , Adulto Jovem
4.
Mycoses ; 62(5): 450-457, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30597630

RESUMO

Although case series of talaromycosis have been reported in China, their detailed clinical and microbiological characteristics have never been systematically profiled. In this study, we report the clinical characteristics, molecular epidemiology, rapid identification and antifungal susceptibilities of talaromycosis in The University of Hong Kong-Shenzhen Hospital in Shenzhen. Seven cases of talaromycosis were observed since commencement of hospital service in 2012. Three patients were local Shenzhen residents, whereas the other four were immigrants from other parts of China. Two patients were HIV-negative, but with underlying diseases requiring immunosuppressive therapy. Two of the seven patients succumbed. All the seven isolates were successfully identified as T. marneffei by MALDI-TOF MS using Bruker database expanded with in-house generated T. marneffei mass spectra. MLST showed that the seven strains belonged to six different, novel sequences types. Phylogenetic analyses of the concatenated five-locus sequence revealed that the seven strains were scattered amongst other T. marneffei strains. The MICs of itraconazole, isavuconazole, posaconazole and voriconazole against the seven clinical isolates were low but MICs of anidulafungin were high. Underlying diseases other than HIV infection are increasingly important risk factors of talaromycosis. MALDI-TOF MS is useful for rapid identification. Highly diverse T. marneffei sequence types were observed.


Assuntos
Antifúngicos/farmacologia , Técnicas Microbiológicas/métodos , Micoses/epidemiologia , Micoses/patologia , Talaromyces/isolamento & purificação , Adulto , Idoso , Feminino , Genótipo , Hong Kong , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Técnicas de Tipagem Micológica , Micoses/diagnóstico , Micoses/microbiologia , Estudos Retrospectivos , Fatores de Risco , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Análise de Sobrevida , Talaromyces/classificação , Talaromyces/efeitos dos fármacos , Talaromyces/genética
5.
Int J Syst Evol Microbiol ; 68(11): 3627-3634, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30303475

RESUMO

Five bacterial strains, UAE-HKU57T, UAE-HKU58, UAE-HKU59, UAE-HKU60 and UAE-HKU61, were isolated in Dubai, UAE, from necrotic foot tissue samples of four dromedaries (Camelus dromedarius) and associated maggots (Wohrlfartia species). They were non-sporulating, Gram-negative, non-motile bacilli. They grew well under aerobic conditions at 37 °C, but not anaerobically. The pH range for growth was pH 7.0-9.0 (optimum, pH 7.5-8.0) and the strains could tolerate NaCl concentrations (w/v) up to 2 % (optimum, 0.5 %). They were catalase- and cytochrome oxidase-positive, but caseinase-, gelatinase- and urease-negative. Their phenotypic characters were distinguishable from other closely related species. Phylogenetic analyses of the almost-complete 16S rRNA gene and partial 23S rRNA gene, gyrB, groEL and recA sequences revealed that the five isolates were most closely related to undescribed Ignatzschineria strain F8392 and Ignatzschineria indica, but in most phylogenies clustered separately from these close relatives. Average nucleotide identity analysis showed that genomes of the five isolates (2.47-2.52 Mb, G+C content 41.71-41.86 mol%) were 98.00-99.97% similar to each other, but ≤87.18 % similar to other Ignatzschineriaspecies/strains. Low DNA relatedness between the five isolates to other Ignatzschineriaspecies/strains was also supported by Genome-to-Genome Distance Calculator analysis. The chemotaxonomic traits of the five strains were highly similar. They were non-susceptible (intermediate or resistant) to tetracycline and resistant to trimethoprim/sulphamethoxazole. The name Ignatzschineria cameli sp. nov. is proposed to accommodate these five strains, with strain UAE-HKU57T (=CCOS1165T=NBRC 113042T) as the type strain.


Assuntos
Camelus/microbiologia , Gammaproteobacteria/classificação , Larva/microbiologia , Necrose/microbiologia , Filogenia , Sarcofagídeos/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Pé/microbiologia , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Genes Bacterianos , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química , Emirados Árabes Unidos
6.
Comput Struct Biotechnol J ; 16: 197-210, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30002790

RESUMO

Aspergillus, Penicillium and Talaromyces are diverse, phenotypically polythetic genera encompassing species important to the environment, economy, biotechnology and medicine, causing significant social impacts. Taxonomic studies on these fungi are essential since they could provide invaluable information on their evolutionary relationships and define criteria for species recognition. With the advancement of various biological, biochemical and computational technologies, different approaches have been adopted for the taxonomy of Aspergillus, Penicillium and Talaromyces; for example, from traditional morphotyping, phenotyping to chemotyping (e.g. lipotyping, proteotypingand metabolotyping) and then mitogenotyping and/or phylotyping. Since different taxonomic approaches focus on different sets of characters of the organisms, various classification and identification schemes would result. In view of this, the consolidated species concept, which takes into account different types of characters, is recently accepted for taxonomic purposes and, together with the lately implemented 'One Fungus - One Name' policy, is expected to bring a more stable taxonomy for Aspergillus, Penicillium and Talaromyces, which could facilitate their evolutionary studies. The most significant taxonomic change for the three genera was the transfer of Penicillium subgenus Biverticillium to Talaromyces (e.g. the medically important thermally dimorphic 'P. marneffei' endemic in Southeast Asia is now named T. marneffei), leaving both Penicillium and Talaromyces as monophyletic genera. Several distantly related Aspergillus-like fungi were also segregated from Aspergillus, making this genus, containing members of both sexual and asexual morphs, monophyletic as well. In the current omics era, application of various state-of-the-art omics technologies is likely to provide comprehensive information on the evolution of Aspergillus, Penicillium and Talaromyces and a stable taxonomy will hopefully be achieved.

7.
Mycoses ; 61(8): 600-609, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29611232

RESUMO

Aspergillosis in falcons may be associated with high mortality and difficulties in clinical and laboratory diagnosis. We previously cloned an immunogenic protein, Afmp1p, in Aspergillus fumigatus and showed that anti-Afmp1p antibodies were present in human patients with A. fumigatus infections. In this study, we hypothesise that a similar Afmp1p-based enzyme-linked immunosorbent assay (ELISA) could be applied to serodiagnose falcon aspergillosis. A specific polyclonal antibody was first generated to detect falcon serum IgY. Horseradish peroxidase-conjugate of this antibody was then used to measure anti-Afmp1p antibodies in sera collected from falcons experimentally infected with A. fumigatus, and the performance of the Afmp1p-based ELISA was evaluated using sera from healthy falcons and falcons with documented A. fumigatus infections. All four experimentally infected falcons developed culture- and histology-proven invasive aspergillosis. Anti-Afmp1p antibodies were detected in their sera. For the Afmp1p-based ELISA, the mean ± SD OD450 nm using sera from 129 healthy falcons was 0.186 ± 0.073. Receiver operating characteristics curve analysis showed an absorbance cut-off value of 0.407. One negative serum gave an absorbance outside the normal range, giving a specificity of 99.2%. For the 12 sera from falcons with confirmed aspergillosis, nine gave absorbance values ≥ cut-off, giving a sensitivity of 75%. The Afmp1p-based ELISA is useful for serodiagnosis of falcons with aspergillosis.


Assuntos
Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Aspergilose/veterinária , Doenças das Aves/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Falconiformes , Glicoproteínas de Membrana/imunologia , Testes Sorológicos/métodos , Animais , Aspergilose/diagnóstico , Curva ROC , Sensibilidade e Especificidade
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