RESUMO
During the SARS-CoV-2 pandemic, rapid and sensitive detection of SARS-CoV-2 has been of high importance for outbreak control. Reverse transcriptase polymerase chain reaction (RT-PCR) is the current gold standard, however, the procedures require an equipped laboratory setting and personnel, which have been regularly overburdened during the pandemic. This often resulted in long waiting times for patients. In contrast, reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) is a simple, cost-efficient, and fast procedure, allowing for rapid and remote detection of SARS-CoV-2. In the current study, we performed a clinical evaluation of a new point-of-care test system based on LAMP-technology for SARS-CoV-2 detection, providing a result within 25 min (1copy™ COVID-19 MDx Kit Professional system). We tested 112 paired nasopharyngeal swabs, collected in the COVID-19 Ghent University Hospital test center, using the 1copy™ COVID-19 MDx Kit Professional system, and RT-PCR as the reference method. The test system was found to have a clinical sensitivity of 93.24% (69/74) (95% confidence interval [CI]: 84.93%-97.77%) and specificity of 97.37% (37/38) (95% CI: 86.19%-99.93%). Due to its easy smartphone operation and ready-to-use reagents, it ought to be easily applied in for instance general practices, pharmacies, nursing homes, schools, and companies. This would facilitate an efficient SARS-CoV-2 outbreak control and quarantine policy, as diagnosis can occur sooner in a near-patient setting.
Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Teste para COVID-19 , Smartphone , Técnicas de Laboratório Clínico/métodos , Sensibilidade e Especificidade , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/genéticaRESUMO
BACKGROUND: Bacterial vaginosis (BV) is a condition that, if symptomatic, is characterized by discharge and odor, with high recurrence rates even when treated. This study aims to review what literature exists on the association between BV and the emotional, sexual, and social health of women. METHODS: MEDLINE, Embase and Web of Science databases were searched from inception until November 2020. Studies reporting an association between women's emotional, sexual and/or social health and symptomatic BV in a qualitative and/or quantitative manner were included. Selected studies were divided in three categories, i.e. reporting on the emotional, sexual and/or social association. All studies were critically evaluated and discussed. RESULTS: Sixteen studies were included. Concerning emotional health, we found eight studies that calculated the association between stress and BV, in four this was statistically significant. Four qualitative studies on emotional health showed that the severity of the symptoms influenced the impact on women's lives. All studies on sexual health reported that many women experienced an impact on their relationship and sexual intimacy. Results for social life ranged from no association found to most of the study population showing avoidance behavior. CONCLUSION: This review shows that symptomatic BV can be associated with diminished emotional, sexual, and social health, but there is too little evidence to state the extent of this association.
Assuntos
Vaginose Bacteriana , Humanos , Feminino , Vaginose Bacteriana/complicações , Vaginose Bacteriana/epidemiologia , Fatores de Risco , Comportamento Sexual , Parceiros Sexuais/psicologia , Pesquisa QualitativaRESUMO
BACKGROUND: The Democratic Republic of the Congo (DRC) has one of the highest neonatal death rates (between 14% and 28%) in the world. In the DRC, neonatal sepsis causes 15.6% of this mortality, but data on the bacterial etiology and associated drug susceptibility are lacking. METHODS: Hemocultures of 150 neonates with possible early-onset neonatal sepsis (pEOS) were obtained at the Hôpital Provincial Général de Référence de Bukavu (Bukavu, DRC). The newborns with pEOS received an empirical first-line antimicrobial treatment (ampicillin, cefotaxime, and gentamicin) based on the synopsis of international guidelines for the management of EOS that are in line with World Health Organization (WHO) recommendations. Isolates were identified using matrix-assisted laser desorption/ ionization time-of-flight mass spectrophotometry. Antibiotic resistance was assessed using the disk diffusion method. RESULTS: Fifty strains were obtained from 48 patients and identified. The 3 most prevalent species were Enterobacter cloacae complex (42%), Klebsiella pneumoniae (18%), and Serratia marcescens (12%). Enterobacter cloacae isolates were resistant to all first-line antibiotics. All K. pneumoniae and S. marcescens isolates were resistant to ampicillin, and the majority of the K. pneumoniae and half of the S. marcescens isolates were resistant to both cefotaxime and gentamicin. All E. cloacae complex strains, 89% of K. pneumoniae, and half of S. marcescens had an extended-spectrum ß-lactamase phenotype. CONCLUSIONS: The most prevalent pathogens causing EOS in Bukavu were E. cloacae complex, K. pneumoniae, and S. marcescens. Most of these isolates were resistant to the WHO-recommended antibiotics.
Assuntos
Sepse Neonatal , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , República Democrática do Congo/epidemiologia , Resistência Microbiana a Medicamentos , Humanos , Recém-Nascido , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Sepse Neonatal/tratamento farmacológico , Sepse Neonatal/epidemiologia , beta-LactamasesRESUMO
OBJECTIVES: Neonatal sepsis, a condition defined as bacteremia within the first month of life accompanied by signs of systemic infection, is the most preventable cause of infant mortality in sub-Saharan Africa. Despite the development of new infection markers, C-reactive protein (CRP) is the most extensively studied acute phase reactant so far and the preferred index in many neonatal intensive care units (NICUs). The aim of the present study was to evaluate an affordable, non-commercial turbidimetric CRP assay for monitoring early-onset neonatal sepsis (EOS). METHODS: A total of 148 neonates admitted at the NICU of the Hôpital Provincial Général de Référence de Bukavu to diagnose and to monitor EOS were enrolled in the study. CRP was assayed using a functional turbidimetric assay based on the interaction of CRP with phosphocholine containing particles (Intralipid®). RESULTS: In total, 62/148 (41.9%) cases were identified as blood culture-proven EOS. Different serum CRP slopes were observed among the different birth weight categories. Moreover, the serum (CRP 48 h-CRP 12 h) difference and the birth weight predicted the outcome of these septic newborns. CONCLUSIONS: Our turbidimetric CRP assay is a potential novel tool that can be used in the management of EOS in sub-Saharan Africa. The simplicity of the assay and the extremely low price make the CRP method very well suited for developing countries.
Assuntos
Sepse Neonatal , Sepse , Peso ao Nascer , Proteína C-Reativa/análise , República Democrática do Congo , Humanos , Recém-Nascido , Sepse Neonatal/diagnóstico , Sepse/diagnósticoRESUMO
Starting and stopping preventive chemotherapy (PC) for soil-transmitted helminthiasis is typically based on the prevalence of infection as measured by Kato-Katz (KK) fecal smears. Kato-Katz-based egg counts can vary highly over repeated stool samples and smears. Consequentially, the sensitivity of KK-based surveys depends on the number of stool samples per person and the number of smears per sample. Given finite resources, collecting multiple samples and/or smears means screening fewer individuals, thereby lowering the statistical precision of prevalence estimates. Using population-level data from various epidemiological settings, we assessed the performance of different sampling schemes executed within the confines of the same budget. We recommend the use of single-slide KK for determining prevalence of moderate-to-heavy intensity infection and policy decisions for starting and continuing PC; more sensitive sampling schemes may be required for policy decisions involving stopping PC. Our findings highlight that guidelines should include specific guidance on sampling schemes.
Assuntos
Tomada de Decisões , Helmintíase/prevenção & controle , Helmintíase/transmissão , Solo/parasitologia , Conjuntos de Dados como Assunto , Fezes/parasitologia , Helmintíase/epidemiologia , Helmintíase/parasitologia , Humanos , Contagem de Ovos de Parasitas , Serviços Preventivos de Saúde , Sensibilidade e Especificidade , Manejo de EspécimesRESUMO
OBJECTIVES: Trichomoniasis is the most prevalent curable STI globally, with the highest incidence and prevalence in sub-Saharan Africa (sSA). STIs have largely been associated with an increase in HIV acquisition. Our objective was to assess the existing literature available in English regarding the association of Trichomoniasis and HIV-1 acquisition. METHODS: The review protocol was registered at the International Prospective Register of Systematic Reviews (PROSPERO) under number CRD42018082702. We searched MEDLINE, Embase and Scopus databases to collect articles measuring the association of Trichomonas vaginalis infection and HIV acquisition and performed a meta-analysis and qualitative synthesis of the literature. RESULTS: We identified 1806 unduplicated citations, of which 18 papers and 1 conference abstract were eligible for inclusion in the review after applying our inclusion and exclusion criteria. All the studies included in the systematic review had been carried out in sSA. The articles reported various measures of effects, namely: HRs, rate ratios, risk ratios and ORs. In a meta-analysis restricted to 11 studies reporting HR, individuals infected with T. vaginalis were 1.5 times more likely to acquire HIV compared with individuals not infected with T. vaginalis (95% CI 1.3 to 1.7; p<0.001). CONCLUSIONS: T. vaginalis is an important factor in HIV acquisition especially in sSA where the prevalence of both T. vaginalis and HIV-1 are high. This systematic review and meta-analysis confirms the evidence that infection with T. vaginalis augments HIV acquisition with 50%. Diagnosis and treatment of T. vaginalis infection in both high-risk and low-risk individuals may be a potential tool to reduce new HIV infections. TRIAL REGISTRATION NUMBER: CRD42018082702.
Assuntos
Infecções por HIV/transmissão , HIV-1 , Tricomoníase/epidemiologia , Trichomonas vaginalis , África Subsaariana/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Razão de Chances , Prevalência , Modelos de Riscos ProporcionaisRESUMO
Whole genome sequence analysis (digital DNA-DNA hybridization and average nucleotide identity) was carried out for 81 sequenced full genomes of the genus Gardnerella, including ten determined in this study, and indicated the existence of 13 genomic species, of which five consist of only one strain and of which only five contain more than four sequenced genomes. Furthermore, a collection of ten Gardnerella strains, representing the emended species G. vaginalis and the newly described species Gardnerella leopoldii, Gardnerella piotii and Gardnerella swidsinskii, was studied. Matrix-assisted laser desorption ionization time-of-flight MS analysis of the protein signatures identified specific peaks that can be used to differentiate these four species. Only strains of G. vaginalis produce ß-galactosidase. We emend the description of G. vaginalis (type strain ATCC 14018T=LMG 7832T=CCUG 3717T) and describe the novel species Gardnerella leopoldii sp. nov. (UGent 06.41T=LMG 30814T=CCUG 72425T), Gardnerella piotii sp. nov. (UGent 18.01T=LMG 30818T=CCUG 72427T) and Gardnerella swidsinskii sp. nov. (GS 9838-1T=LMG 30812T=CCUG 72429T).
Assuntos
Gardnerella vaginalis/classificação , Gardnerella/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
BACKGROUND: Screening of curable sexually transmitted infections is frequently oriented towards the diagnosis of chlamydia, gonorrhea, syphilis and trichomoniasis, whereas other pathogens, sometimes associated with similar urogenital syndromes, remain undiagnosed and/or untreated. Some of these pathogens are associated with adverse pregnancy outcomes. METHODS: In a nested case-control study, vaginal swabs from 79 pregnant women, i.e., 28 T. vaginalis-positive (cases) and 51 T. vaginalis-negative (controls), were screened by quantitative PCR for Adenovirus 1 and 2, Cytomegalovirus, Herpes Simplex Virus 1 and 2, Chlamydia trachomatis, Escherichia coli, Haemophilus ducreyi, Mycoplasma genitalium, M. hominis, candidatus M. girerdii, Neisseria gonorrhoeae, Streptococcus agalactiae, Treponema pallidum, Ureaplasma parvum, U. urealyticum, and Candida albicans. Additionally, we determined whether women with pathogens highly associated with T. vaginalis had distinct clinical signs and symptoms compared to women with T. vaginalis mono-infection. RESULTS: M. hominis was independently associated with T. vaginalis (adjusted odds ratio = 6.8, 95% CI: 2.3-19.8). Moreover, M. genitalium and Ca M. girerdii were exclusively detected in women with T. vaginalis (P = 0.002 and P = 0.001), respectively. Four of the six women co-infected with T. vaginalis and Ca M. girerdii complained of vaginal itching, compared to only 4 out of the 22 women infected with T. vaginalis without Ca M. girerdii (P = 0.020). CONCLUSION: We confirm M. hominis as a correlate of T. vaginalis in our population, and the exclusive association of both M. genitalium and Ca. M. girerdii with T. vaginalis. Screening and treatment of these pathogens should be considered.
Assuntos
Coinfecção , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/microbiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Tricomoníase/epidemiologia , Trichomonas vaginalis/isolamento & purificação , Sistema Urogenital/microbiologia , Adolescente , Adulto , Estudos de Casos e Controles , Chlamydia trachomatis/isolamento & purificação , Coinfecção/epidemiologia , Coinfecção/microbiologia , Feminino , Gonorreia/epidemiologia , Gonorreia/microbiologia , Humanos , Quênia/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Neisseria gonorrhoeae/isolamento & purificação , Gravidez , Infecções Sexualmente Transmissíveis/microbiologia , Streptococcus agalactiae/isolamento & purificação , Sífilis/epidemiologia , Sífilis/microbiologia , Treponema pallidum/isolamento & purificação , Tricomoníase/microbiologia , Adulto JovemRESUMO
BACKGROUND: Achromobacter xylosoxidans is increasingly being recognized as an emerging pathogen in cystic fibrosis. Recent severe infections with A. xylosoxidans in some of our cystic fibrosis (CF) patients led to a re-evaluation of the epidemiology of CF-associated A. xylosoxidans infections in two Belgian reference centres (Antwerp and Ghent). Several of these patients also stayed at the Rehabilitation Centre De Haan (RHC). In total, 59 A. xylosoxidans isolates from 31 patients (including 26 CF patients), collected between 2001 and 2014, were studied. We evaluated Matrix Assisted Laser Desorption Ionisation -Time of Flight mass spectrometry (MALDI-TOF) as an alternative for McRAPD typing. RESULTS: Both typing approaches established the presence of a major cluster, comprising isolates, all from 21 CF patients, including from two patients sampled when staying at the RHC a decade ago. This major cluster was the same as the cluster established already a decade ago at the RHC. A minor cluster consisted of 13 isolates from miscellaneous origin. A further seven isolates, including one from a non-CF patient who had stayed recently at the RHC, were singletons. CONCLUSIONS: Typing results of both methods were similar, indicating transmission of a single clone of A. xylosoxidans among several CF patients from at least two reference centres. Isolates of the same clone were already observed at the RHC, a decade ago. It is difficult to establish to what extent the RHC is the source of transmission, because the epidemic strain was already present when the first epidemiological study in the RHC was carried out. This study also documents the applicability of MALDI-TOF for typing of strains within the species A. xylosoxidans and the need to use the dynamic cutoff algorithm of the BioNumerics® software for correct clustering of the fingerprints.
Assuntos
Achromobacter denitrificans/isolamento & purificação , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Achromobacter denitrificans/classificação , Achromobacter denitrificans/genética , Técnicas de Tipagem Bacteriana , Bélgica/epidemiologia , Fibrose Cística/epidemiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , HumanosRESUMO
Otitis media with effusion (OME) is a highly prevalent disease in children, but the exact pathogenesis and role of bacteria are still not well understood. This study aimed to investigate the presence of otopathogenic bacteria in the middle ear effusion (MEE) and adenoid of children with chronic OME (COME), and to investigate in vivo whether these bacteria, especially Haemophilus influenzae, are organized as a biofilm in the middle ear fluid. MEE and adenoid samples were collected from 21 patients with COME. Extensive bacterial culturing and genotyping was performed on all middle ear and adenoid samples. Fluorescence in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM) was used to visualize possible biofilm structures for a selection of middle ear effusion samples. 34 MEE samples were collected from 21 patients of which 64.7 % were culture positive for bacteria and 47.0 % were culture positive for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and/or Streptococcus pneumoniae. All 21 adenoid samples were culture positive for one or more of these four otopathogens. H. influenzae (35.3 %) and S. pneumoniae (76.2 %) were the most frequently cultured bacteria in the MEE and adenoid samples, respectively. The same bacterial species was found in MEE and adenoid for 84.6 % of the patients and in 81.2 % of the cases where the same species was found in more than one site it involved the same bacterial genotype. FISH and CLSM demonstrated the presence of H. influenzae specific biofilm structures in five of the eight culture positive MEEs that were tested, but in none of the two culture negative MEEs. The findings in this study indicate that the adenoid acts as a reservoir for bacteria in MEE and confirms that biofilms, in at least half of the cases consisting of H. influenzae, are indeed present in the MEE of children with COME. Biofilms may thus play a crucial role in the pathogenesis of COME, which is important in the understanding of this disease and the development of potential future treatment options.
Assuntos
Biofilmes/crescimento & desenvolvimento , Haemophilus influenzae/fisiologia , Otite Média com Derrame/microbiologia , Tonsila Faríngea/microbiologia , Criança , Pré-Escolar , Doença Crônica , Orelha Média/microbiologia , Feminino , Genótipo , Haemophilus influenzae/isolamento & purificação , Humanos , Hibridização in Situ Fluorescente , Lactente , Masculino , Microscopia Confocal , Moraxella catarrhalis/isolamento & purificação , Moraxella catarrhalis/fisiologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/fisiologia , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/fisiologiaRESUMO
BACKGROUND: Women in sub-Saharan Africa are vulnerable to acquiring HIV infection and reproductive tract infections. Bacterial vaginosis (BV), a disruption of the vaginal microbiota, has been shown to be strongly associated with HIV infection. Risk factors related to potentially protective or harmful microbiota species are not known. METHODS: We present cross-sectional quantitative polymerase chain reaction data of the Lactobacillus genus, five Lactobacillus species, and three BV-related bacteria (Gardnerella vaginalis, Atopobium vaginae, and Prevotella bivia) together with Escherichia coli and Candida albicans in 426 African women across different groups at risk for HIV. We selected a reference group of adult HIV-negative women at average risk for HIV acquisition and compared species variations in subgroups of adolescents, HIV-negative pregnant women, women engaging in traditional vaginal practices, sex workers and a group of HIV-positive women on combination antiretroviral therapy. We explored the associations between presence and quantity of the bacteria with BV by Nugent score, in relation to several factors of known or theoretical importance. RESULTS: The presence of species across Kenyan, South African and Rwandan women was remarkably similar and few differences were seen between the two groups of reference women in Kenya and South Africa. The Rwandan sex workers and HIV-positive women had the highest G. vaginalis presence (p = 0.006). Pregnant women had a higher Lactobacillus genus mean log (7.01 genome equivalents (geq)/ml) compared to the reference women (6.08 geq/ml). L. vaginalis (43%) was second to L. iners (81.9%) highly present in women with a normal Nugent score. Recent sexual exposure negatively affected the presence of L. crispatus (<0.001), L. vaginalis (p = 0.001), and Lactobacillus genus (p < 0.001). Having more than one sexual partner in the last three months was associated with an increased prevalence of G. vaginalis (p = 0.044) and L. iners (p = 0.001). CONCLUSIONS: Although the composition of species across the studied African countries was similar, the presence of protective species i.e. L. crispatus and L. vaginalis in women with a normal Nugent score appeared lower compared to non-African studies. Furthermore, Lactobacillus species were negatively affected by sexual behavioural. Strategies to support protective Lactobacillus species are urgently needed. TRIAL REGISTRATION: The study is registered at the Trial Registration at the National Health Research Ethics Council South Africa with the number DOH2709103223.
Assuntos
Portador Sadio/microbiologia , Coito , Gardnerella vaginalis/genética , Infecções por HIV/complicações , Lactobacillus/genética , Complicações Infecciosas na Gravidez/microbiologia , Vagina/microbiologia , Vaginose Bacteriana/microbiologia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Adolescente , Adulto , Candida albicans/genética , Candida albicans/isolamento & purificação , Portador Sadio/epidemiologia , Estudos de Casos e Controles , Estudos Transversais , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Gardnerella vaginalis/isolamento & purificação , Infecções por HIV/epidemiologia , Humanos , Quênia , Lactobacillus/isolamento & purificação , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Prevotella/genética , Prevotella/isolamento & purificação , Ruanda , Profissionais do Sexo/estatística & dados numéricos , África do Sul , Vaginose Bacteriana/complicações , Vaginose Bacteriana/epidemiologiaRESUMO
Atopobium species are Gram-positive, anaerobic, catalase-negative, fastidious bacteria belonging to the family Coriobacteriaceae. We report the isolation of an Atopobium-like species in a patient with Fournier's gangrene and highlight the role of 16S rRNA gene sequencing in the identification of fastidious organisms in the clinical laboratory.
Assuntos
Actinobacteria/isolamento & purificação , Gangrena de Fournier/complicações , Gangrena de Fournier/microbiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/microbiologia , Sepse/diagnóstico , Sepse/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Adulto , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Mycobacterium tilburgii is a nonculturable nontuberculous mycobacterium identifiable only by molecular methods. We report a case of disseminated M. tilburgii infection illustrating the importance of 16S rRNA gene sequencing to determine the responsible mycobacterial pathogen and the difficulties in tailoring antimycobacterial treatment in the absence of a culturable organism.
Assuntos
Hospedeiro Imunocomprometido/efeitos dos fármacos , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/genética , Adulto , Antibacterianos/uso terapêutico , Humanos , Masculino , Dados de Sequência Molecular , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Micobactérias não Tuberculosas/efeitos dos fármacos , RNA Ribossômico 16S/genéticaRESUMO
A Gram-stain-positive, obligately anaerobic, short rod, designated strain HHRM1715(T), was isolated from the blood of a patient with Fournier's gangrene, complicated by sepsis. On the basis of 16S rRNA gene sequence analysis, strain HHRM1715(T) was shown to belong to the genus Atopobium and was most closely related to Atopobium minutum (95â% similarity). The results of 16S rRNA-gene-based phylogenetic analysis, cellular fatty acid analysis and differential biochemical tests, showed that strain HHRM1715(T) represented a novel species of the genus Atopobium. We therefore describe Atopobium deltae sp. nov. with HHRM1715(T) (â=âLMG 27987(T)â=âCCUG 65171(T)) as the type strain and propose an emended description of the genus Atopobium with regard to the DNA G+C content.
Assuntos
Actinobacteria/classificação , Gangrena de Fournier/microbiologia , Filogenia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Gangrena de Fournier/sangue , Humanos , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
We previously reported the presence of an OXA-23 carbapenemase in an undescribed species of the genus Acinetobacter isolated from horse dung at the Faculty of Veterinary Medicine, Ghent University, Belgium. Here we include six strains to corroborate the delineation of this taxon by phenotypic characterization, DNA-DNA hybridization, 16S rRNA gene and rpoB sequence analysis, % G+C determination, MALDI-TOF MS and fatty acid analysis. The nearly complete 16S rRNA gene sequence of strain UG 60467(T) showed the highest similarities with those of the type strains of Acinetobacter bouvetii (98.4â%), Acinetobacter haemolyticus (97.7â%), and Acinetobacter schindleri (97.2â%). The partial rpoB sequence of strain UG 60467(T) showed the highest similarities with 'Acinetobacter bohemicus' ANC 3994 (88.6â%), A. bouvetii NIPH 2281 (88.6â%) and A. schindleri CIP 107287T (87.3â%). Whole-cell MALDI-TOF MS analyses supported the distinctness of the group at the protein level. The predominant fatty acids of strain UG 60467(T) were C12â:â0 3-OH, C12â:â0, C16â:â0, C18â:â1ω9c and summed feature 3 (C16â:â1ω7c and/or iso-C15â:â0 2-OH). Strains UG 60467(T) and UG 60716 showed a DNA-DNA relatedness of 84â% with each other and a DNA-DNA relatedness with A. schindleri LMG 19576(T) of 17â% and 20â%, respectively. The DNA G+C content of strain UG 60467(T) was 39.6 mol%. The name Acinetobacter gandensis sp. nov. is proposed for the novel taxon. The type strain is UG 60467(T) (â=âANC 4275(T)â=âLMG 27960(T)â=âDSM 28097(T)).
Assuntos
Acinetobacter/classificação , Bovinos/microbiologia , Cavalos/microbiologia , Filogenia , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bélgica , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Genes Bacterianos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Hot springs are potential sources of diverse arrays of microbes and their thermostable hydrolytic enzymes. Water and sediment samples were collected from three hot springs of Ethiopia and enriched on nutrient and thermus agar media to isolate pure cultures of potential microbes. A total of 252 bacterial isolates were screened and evaluated for the production of amylase, protease, cellulase, and lipase. About 95.23%, 84.12%, 76.58%, and 65.07% of the isolates displayed promising amylase, proteases, cellulase, and lipase activities, respectively. Based on the diameter of the clear zone formed, 45 isolates were further screened and identified to species level using matrix-assisted laser desorption/ionization time-of-flight-mass spectrometry analysis and 16S rRNA gene sequencing. Five of the 45 isolates showed significantly high (P < 0.05) clear zone ratios as compared to others. The identified isolates were categorized under five bacterial species, namely, Bacillus licheniformis, Bacillus cereus, Paenibacillus thiaminolyticus, Paenibacillus dendritiformis, and Brevibacillus borstelensis. The most dominant species (66.7%) was B. licheniformis. It could be concluded that hot springs of Ethiopia are potential sources of thermostable extracellular hydrolytic enzymes for various industrial applications. Further optimization of the growth conditions and evaluation for better productivity of the desired products is recommended before attempting for large-scale production of the hydrolytic enzymes. IMPORTANCE: Thermostable microbial enzymes play an important role in industries due to their stability under harsh environmental conditions, including extreme temperatures. Despite their huge application in different industries, however, the thermostable enzymes of thermophilic microorganism origin have not yet been fully explored in Ethiopia. Here, we explored thermophilic bacteria and their enzymes from selected hot spring water and sediment samples. Accordingly, thermophilic bacteria were isolated and screened for the production of extracellular hydrolytic enzymes. Promising numbers of isolates were found as producers of the enzymes. The potent enzyme producers were further identified using matrix-assisted laser desorption/ionization time-of-flight-mass spectrometry analysis and 16S rRNA gene sequencing. The findings revealed the presence of potential hydrolytic enzyme-producing thermophilic bacteria in hot springs of Ethiopia and necessitate further comprehensive study involving other extreme environments. Our findings also revealed the potential of Ethiopian hot springs in the production of thermostable enzymes of significant application in different industries, including food industries.
Assuntos
Celulases , Fontes Termais , Fontes Termais/microbiologia , RNA Ribossômico 16S/genética , Etiópia , Lipase , Peptídeo Hidrolases , Endopeptidases , Amilases , ÁguaRESUMO
Accurate DNA quantification is key for downstream application including library preparations for whole genome sequencing (WGS) and the quantification of standards for quantitative PCR. Two commonly used technologies for nucleic acid quantification are based on spectrometry, such as NanoDrop, and fluorometry, such as Qubit. The DS-11+ Series spectrophotometer/fluorometer (DeNovix) is a UV spectrophotometry-based instrument and is a relatively new spectrophotometric method but has not yet been compared to established platforms. Here, we compared three DNA quantification platforms, including two UV spectrophotometry-based techniques (DeNovix and NanoDrop) and one fluorometry-based approach (Qubit). We used genomic prokaryotic DNA extracted from Streptococcus pneumoniae using a Roche DNA extraction kit. We also evaluated purity assessment and effect of a single freeze-thaw cycle. Spectrophotometry-based methods reported 3 to 4-fold higher mean DNA concentrations compared to Qubit, both before and after freezing. The ratio of DNA concentrations assessed by spectrophotometry on the one hand, and Qubit on the other hand, was function of the A260/280. In case DNA was pure (A260/280 between 1.7 and 2.0), the ratio DeNovix or Nanodrop vs. Qubit was close or equal to 2, while this ratio showed an incline for DNA with increasing A260/280 values > 2.0. The A260/280 and A260/230 purity ratios exhibited negligible variation across spectrophotometric methods and freezing conditions. The comparison of DNA concentrations from before and after freezing revealed no statistically significant disparities for each technique. DeNovix exhibited the highest Spearman correlation coefficient (0.999), followed by NanoDrop (0.81), and Qubit (0.77). In summary, there is no difference between DeNovix and NanoDrop in estimated gDNA concentrations of S. pneumoniae, and the spectrophotometry methods estimated close or equal to 2 times higher concentrations compared to Qubit for pure DNA.
Assuntos
DNA Bacteriano , Streptococcus pneumoniae , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação , Fluorometria/métodos , Espectrofotometria Ultravioleta/métodos , Espectrofotometria/métodos , Lisados BacterianosRESUMO
We describe vaginal microbiota, including Gardnerella species and sexually transmitted infections (STIs), during pregnancy and their associations with recurrent spontaneous preterm birth (sPTB). We performed a prospective cohort study in a tertiary referral centre in the Netherlands, among pregnant women with previous sPTB <34 weeks' gestation. Participants collected three vaginal swabs in the first and second trimester. Vaginal microbiota was profiled with 16S rDNA sequencing. Gardnerella species and STI's were tested with qPCR. Standard care was provided according to local protocol, including screening and treatment for bacterial vaginosis (BV), routine progesterone administration and screening for cervical length shortening. Of 154 participants, 26 (16.9 %) experienced recurrent sPTB <37 weeks' gestation. Microbiota composition was not associated with sPTB. During pregnancy, the share of Lactobacillus iners-dominated microbiota increased at the expense of diverse microbiota between the first and second trimester. This change coincided with treatment for BV, demonstrating a similar change in microbiota composition after treatment. In this cohort of high-risk women, we did not find an association between vaginal microbiota composition and recurrent sPTB. This should be interpreted with care, as these women were offered additional preventive therapies to reduce sPTB according to national guidelines including progesterone and BV treatment. The increase observed in L. iners dominated microbiota and the decrease in diverse microbiota mid-gestation was most likely mediated by BV treatment. Our findings suggest that in recurrent sPTB occurring despite several preventive therapies, the microbe-related etiologic contribution might be limited.
RESUMO
Introduction: Vaginal Candida colonization (CC) can lead to vulvovaginal candidiasis, the second most prevalent vaginal condition worldwide, and has been associated with adverse birth outcomes. However, no data on CC in the Democratic Republic of the Congo are available. We investigated the prevalence, Candida species, clinical correlates, risk factors and pregnancy outcomes in women with CC in the second trimester of pregnancy. Material and methods: In Bukavu, the Democratic Republic of the Congo, pregnant women were recruited during antenatal care between 16 and 20 weeks of gestation from January 2017 to October 2017 and followed until delivery. Sociodemographics, sexual behavioral, hygienic and clinical characteristics, microbiological data and pregnancy outcomes were collected. Candida detection and speciation was performed with microscopy (Gram-stained smears and wet-mount) and/or quantitative PCR. Multivariate regression models were used to estimate the different associations with CC. Results: The prevalence of CC by wet mount, microscopy of Gram-stain smears and qPCR was 27.9%, 28.1% and 38.2%, respectively. C. albicans was the most prevalent Candida species (91.0%). Previous genital infections, an intermediate vaginal microbiota, bacterial vaginosis, and the use of pit toilets were risk factors for CC. Clinically, CC was associated with itching only. Women with CC had twice the odds for preterm birth, if Candida concentration was high, the odds were four times higher. Conclusions: In Bukavu, the Democratic Republic of the Congo, the prevalence of CC was high and associated with microbiological and modifiable risk factors. Screening and treatment for CC during antenatal care should be investigated as a possible strategy to reduce preterm birth.