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2.
Science ; 379(6627): 11-12, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36603077
3.
Science ; 379(6627): 16-17, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36603095
4.
Artigo em Inglês | MEDLINE | ID: mdl-36603473

RESUMO

Recombinant SARS-CoV-2 trimeric spike protein produced by mammalian cell culture is a potential candidate for a COVID-19 vaccine. However, this protein is much larger than most typical biopharmaceutical proteins and its large-scale manufacture is therefore challenging. Particularly, its purification using resin-based chromatography is difficult as the diffusive transport of this protein to and from its binding site within the pores of the stationary phase particles is slow. Therefore, very low flow rates need to be used during binding and elution, and this slows down the purification process. Also, due to its large size, the binding capacity of this protein on resin-based media is low. Membrane chromatography is an efficient and scalable technique for purifying biopharmaceuticals. The predominant mode of solute transport in a membrane is convective and hence it is considered better than resin-based chromatography for purifying large proteins. In this paper, we propose a membrane chromatography-based purification method for fast and scalable manufacture of recombinant SARS-CoV-2 trimeric spike protein. A combination of cation exchange z2 laterally-fed membrane chromatography and size exclusion chromatography was found to be suitable for obtaining a homogeneous spike protein sample from mammalian cell culture supernatant. The proposed method is both fast and scalable and could be explored as a method for manufacturing vaccine grade spike protein.


Assuntos
Proteínas Recombinantes , Glicoproteína da Espícula de Coronavírus , Vacinas contra COVID-19 , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/biossíntese , Glicoproteína da Espícula de Coronavírus/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação
5.
Pediatr Infect Dis J ; 42(2): e52-e53, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638407

RESUMO

The epidemiology and clinical manifestations of human metapneumovirus are not well studied in infants younger than 60 days of age. In this retrospective review of infants admitted for sepsis evaluation, we identified HMPV less frequently than other viral etiologies via nasopharyngeal multiplex polymerase chain reaction testing; in only 16 (1.9%) infants. Two infants had apneic episodes, but none had wheezing.


Assuntos
Metapneumovirus , Infecções por Paramyxoviridae , Sepse , Humanos , Lactente , Hospitalização/estatística & dados numéricos , Metapneumovirus/genética , Metapneumovirus/isolamento & purificação , Nasofaringe , Infecções por Paramyxoviridae/diagnóstico , Infecções por Paramyxoviridae/epidemiologia , Infecções por Paramyxoviridae/virologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sepse/diagnóstico , Sepse/epidemiologia , Sepse/etiologia , Sepse/virologia , Fatores Etários
6.
Nucleic Acids Res ; 51(D1): D621-D628, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36624664

RESUMO

Quantitative activity and species source data of natural products (NPs) are important for drug discovery, medicinal plant research, and microbial investigations. Activity values of NPs against specific targets are useful for discovering targeted therapeutic agents and investigating the mechanism of medicinal plants. Composition/concentration values of NPs in individual species facilitate the assessments and investigations of the therapeutic quality of herbs and phenotypes of microbes. Here, we describe an update of the NPASS natural product activity and species source database previously featured in NAR. This update includes: (i) new data of ∼95 000 records of the composition/concentration values of ∼1 490 NPs/NP clusters in ∼390 species, (ii) extended data of activity values of ∼43 200 NPs against ∼7 700 targets (∼40% and ∼32% increase, respectively), (iii) extended data of ∼31 600 species sources of ∼94 400 NPs (∼26% and ∼32% increase, respectively), (iv) new species types of ∼440 co-cultured microbes and ∼420 engineered microbes, (v) new data of ∼66 600 NPs without experimental activity values but with estimated activity profiles from the established chemical similarity tool Chemical Checker, (vi) new data of the computed drug-likeness properties and the absorption, distribution, metabolism, excretion and toxicity (ADMET) properties for all NPs. NPASS update version is freely accessible at http://bidd.group/NPASS.


Assuntos
Produtos Biológicos , Pesquisa Biomédica , Bases de Dados Factuais , Descoberta de Drogas , Preparações Farmacêuticas/isolamento & purificação
7.
PLoS One ; 18(1): e0278675, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36649247

RESUMO

BACKGROUND: HIV may increase SARS-CoV-2 infection risk and COVID-19 severity generally, but data are limited about its impact on postpartum women and their infants. As such, we characterized SARS-CoV-2 infection among mother-infant pairs in Nairobi, Kenya. METHODS: We conducted a nested study of 62 HIV-uninfected and 64 healthy women living with HIV, as well as their HIV-exposed uninfected (N = 61) and HIV-unexposed (N = 64) infants, participating in a prospective cohort. SARS-CoV-2 serology was performed on plasma collected between May 1, 2020-February 1, 2022 to determine the incidence, risk factors, and symptoms of infection. SARS-CoV-2 RNA PCR and sequencing was also performed on available stool samples from seropositive participants. RESULTS: SARS-CoV-2 seropositivity was found in 66% of the 126 mothers and in 44% of the 125 infants. There was no significant association between SARS-CoV-2 infection and maternal HIV (Hazard Ratio [HR] = 0.810, 95% CI: 0.517-1.27) or infant HIV exposure (HR = 1.47, 95% CI: 0.859-2.53). Maternal SARS-CoV-2 was associated with a two-fold increased risk of infant infection (HR = 2.31, 95% CI: 1.08-4.94). Few participants (13% mothers, 33% infants) had symptoms; no participant experienced severe COVID-19 or death. Seroreversion occurred in about half of mothers and infants. SARS-CoV-2 sequences obtained from stool were related to contemporaneously circulating variants. CONCLUSIONS: These data indicate that postpartum Kenyan women and their infants were at high risk for SARS-CoV-2 infection and that antibody responses waned over an average of 8-10 months. However, most cases were asymptomatic and healthy women living with HIV did not have a substantially increased risk of infection or severe COVID-19.


Assuntos
COVID-19 , Infecções por HIV , Feminino , Humanos , Lactente , COVID-19/epidemiologia , COVID-19/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , Quênia/epidemiologia , Período Pós-Parto , Estudos Prospectivos , RNA Viral/análise , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Estudos de Casos e Controles , Fezes/virologia , Reação em Cadeia da Polimerase
8.
J Obstet Gynaecol ; 43(1): 2162867, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36651606

RESUMO

Pregnant women are one of the endangered groups who need special attention in the COVID-19 epidemic. We conducted a systematic review and summarised the studies that reported adverse pregnancy outcomes in pregnant women with COVID-19 infection. A literature search was performed in PubMed and Scopus up to 1 September 2022, for retrieving original articles published in the English language assessing the association between COVID-19 infection and adverse pregnancy outcomes. Finally, in this review study, of 1790 articles obtained in the initial search, 141 eligible studies including 1,843,278 pregnant women were reviewed. We also performed a meta-analysis of a total of 74 cohort and case-control studies. In this meta-analysis, both fixed and random effect models were used. Publication bias was also assessed by Egger's test and the trim and fill method was conducted in case of a significant result, to adjust the bias. The result of the meta-analysis showed that the pooled prevalence of preterm delivery, maternal mortality, NICU admission and neonatal death in the group with COVID-19 infection was significantly more than those without COVID-19 infection (p<.01). A meta-regression was conducted using the income level of countries. COVID-19 infection during pregnancy may cause adverse pregnancy outcomes including of preterm delivery, maternal mortality, NICU admission and neonatal death. Pregnancy loss and SARS-CoV2 positive neonates in Lower middle income are higher than in High income. Vertical transmission from mother to foetus may occur, but its immediate and long-term effects on the newborn are unclear.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Resultado da Gravidez , Feminino , Humanos , Recém-Nascido , Gravidez , COVID-19/complicações , COVID-19/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Morte Perinatal/etiologia , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/virologia , SARS-CoV-2/isolamento & purificação , Mortalidade Materna , Unidades de Terapia Intensiva Neonatal , Admissão do Paciente/estatística & dados numéricos
9.
Malar J ; 22(1): 18, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650533

RESUMO

BACKGROUND: Plasmodium vivax malaria is one of the major infectious diseases of public health concern in Nouakchott, the capital city of Mauritania and the biggest urban setting in the Sahara. The assessment of the current trends in malaria epidemiology is primordial in understanding the dynamics of its transmission and developing an effective control strategy. METHODS: A 6 year (2015-2020) prospective study was carried out in Nouakchott. Febrile outpatients with a clinical suspicion of malaria presenting spontaneously at Teyarett Health Centre or the paediatric department of Mother and Children Hospital Centre were screened for malaria using a rapid diagnostic test, microscopic examination of Giemsa-stained blood films, and nested polymerase chain reaction. Data were analysed using Microsoft Excel and GraphPad Prism and InStat software. RESULTS: Of 1760 febrile patients included in this study, 274 (15.5%) were malaria-positive by rapid diagnostic test, 256 (14.5%) were malaria-positive by microscopy, and 291 (16.5%) were malaria-positive by PCR. Plasmodium vivax accounted for 216 of 291 (74.2%) PCR-positive patients; 47 (16.1%) and 28 (9.6%) had P. falciparum monoinfection or P. vivax-P. falciparum mixed infection, respectively. During the study period, the annual prevalence of malaria declined from 29.2% in 2015 to 13.2% in 2019 and 2.1% in 2020 (P < 0.05). Malaria transmission was essentially seasonal, with a peak occurring soon after the rainy season (October-November), and P. vivax infections, but not P. falciparum infections, occurred at low levels during the rest of the year. The most affected subset of patient population was adult male white and black Moors. The decline in malaria prevalence was correlated with decreasing annual rainfall (r = 0.85; P = 0.03) and was also associated with better management of the potable water supply system. A large majority of included patients did not possess or did not use bed nets. CONCLUSIONS: Control interventions based on prevention, diagnosis, and treatment should be reinforced in Nouakchott, and P. vivax-specific control measures, including chloroquine and 8-aminoquinolines (primaquine, tafenoquine) for treatment, should be considered to further improve the efficacy of interventions and aim for malaria elimination.


Assuntos
Malária Vivax , Plasmodium vivax , Adulto , Criança , Feminino , Humanos , Masculino , Febre , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Mauritânia/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Estudos Prospectivos
10.
Water Sci Technol ; 87(1): 239-250, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36640035

RESUMO

In recent decades, antibiotic-resistant bacteria (ARB) emerged and spread among humans and animals worldwide. In this study, we evaluated the presence of ARB and antibiotic resistance genes (ARGs) in the raw sewage of two hospitals in Brazil. Sewage aliquots were inoculated in a selective medium with antibiotics. Bacterial identification was performed by MALDI-TOF and ARGs were assessed by polymerase chain reaction (PCR). A total of 208 strains from both hospitals were isolated (H1 = 117; H2 = 91). A wide variety of Enterobacterales and non-Enterobacterales species were isolated and most of them were Enterobacter spp. (13.0%), Proteus mirabilis (10.1%), and Klebsiella pneumoniae (9.6%). blaTEM and blaKPC were the most frequent ß-lactamase-encoding genes and the predominant macrolide resistance genes were mph(A) and mel. Many species had the three tetracycline resistance genes (tetD, tetM, tetA) and strB was the prevalent aminoglycoside resistance gene. Two Staphylococcus haemolyticus strains had the mecA gene. Quinolone, colistin, and vancomycin resistance genes were not found. This study showed that hospital raw sewage is a great ARB and ARG disseminator. Strict monitoring of hospital sewage treatment is needed to avoid the spread of these genes among bacteria in the environment.


Assuntos
Antibacterianos , Bactérias , Farmacorresistência Bacteriana , Esgotos , Antibacterianos/farmacologia , Bactérias/genética , Bactérias/isolamento & purificação , Brasil , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Hospitais , Macrolídeos , Esgotos/microbiologia
11.
Eur J Med Chem ; 245(Pt 1): 114892, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36334326

RESUMO

Cistanche deserticola is a traditional and precious Chinese herbal medicine, known as "desert ginseng", with anti-inflammatory, anti-oxidant, improving immunity, nourishing the kidneys and other pharmacological effects. Its chemical components mainly include phenylethanol glycosides, iridoids, polysaccharides and volatile components, among which polysaccharides have received extensive attention due to their biological activities such as regulating immune activity, anti-aging, anti-spleen deficiency and antitumor. In recent years, a large number of research have been carried out on the extraction and isolation, chemical structure analysis and biological activity of Cistanche deserticola polysaccharides. The methods of polysaccharide extraction mainly include traditional extraction method, ultrasonic assisted method, microwave assisted method and enzyme assisted method, etc. The extracted polysaccharides were analyzed by chemical methods including methylation, acid hydrolysis and Smith degradation and spectroscopy methods such as NMR and IR. A variety of polysaccharides with new structures were obtained, and some polysaccharides with known structures were also investigated for their biological activities and their structure-activity relationships. However, the relationship between polysaccharides structure and their biological activities is still unclear due to the large number of polysaccharide components, their complex structures and the lack of systematic research and analysis on them. It is expected that the subsequent study of polysaccharide structure and active conformational relationship will be highly valuable for the application of Cistanche deserticola in pharmaceutical sciences and health food.


Assuntos
Cistanche , Medicamentos de Ervas Chinesas , Polissacarídeos , Cistanche/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia
12.
ACS Nano ; 17(1): 212-220, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36579744

RESUMO

We developed an on-chip enrichment method based on an aqueous two-phase system of dextran/polyethylene glycol mix, DEX/PEG ATPS, for digital bioassay. Accordingly, we prepared an array device of femtoliter reactors that displays millions of uniformly shaped DEX-rich droplets under a PEG-rich medium. The DEX-rich droplets effectively enriched DNA molecules from the PEG-rich medium. To quantify the enrichment power of the system, we performed a digital bioassay of alkaline phosphatase (ALP). Upon genetically tagging ALP molecules with the DEX-binding domain (DBD) derived from dextransucrase, the ALP molecules were enriched 59-fold in the DEX droplets in comparison to that in a conventional digital bioassay. Subsequently, we performed a Cas13-based digital SARS-CoV-2 RNA detection assay to evaluate the performance of this system for a more practical assay. In this assay, the target RNA molecules bound to the DBD-tagged Cas13 molecules were effectively enriched in the DEX droplets. Consequently, an enrichment factor of 31 was achieved. Enrichment experiments for nonlabeled proteins were also performed to test the expandability of this technique. The model protein, nontagged ß-galactosidase, was enriched in DEX droplets containing DBD-tagged antibody, with an enrichment factor of over 100. Thus, this system enabled effective on-chip enrichment of target molecules to enhance the detection sensitivity of digital bioassays without using external instruments or an external power source, which would be applicable for on-site bioassays or portable diagnostic tests.


Assuntos
COVID-19 , RNA Viral , Humanos , COVID-19/diagnóstico , Polietilenoglicóis/química , RNA Viral/isolamento & purificação , SARS-CoV-2
13.
Diagn Microbiol Infect Dis ; 105(2): 115862, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36493571

RESUMO

The spread of vector habitats along with increasing human mobility can introduce atypical Leishmania species and hence can challenge existing diagnostic practices for rapid detection of active infection with species outside the narrow target range. Here we assessed the pan-Leishmania detection ability of isothermal recombinase polymerase amplification (RPA) assays targeting 18S rRNA gene, cathepsin L-like cysteine proteinase B (Cpb) gene, and kinetoplast minicircle DNA (kDNA) regions. While the lowest limit of detection of the 18S rRNA-RPA and Cpb-RPA assays were estimated as 12 and 17 standard DNA molecules, respectively, both assays could amplify genomic DNA of 7 pathogenic Leishmania species. Evaluation of 18S rRNA-RPA and our previously developed kDNA-RPA assays on 70 real-time PCR-positive leishmaniasis samples of varying pathologies resulted in sensitivity rates of 35.71% and 88.57%, respectively, while the combined sensitivity was 98.57%. Combinatorial application of 18S rRNA-RPA and kDNA-RPA assays can be recommended for further diagnostic assessments.


Assuntos
Leishmania , Humanos , DNA de Cinetoplasto/genética , Leishmania/genética , Leishmania/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Recombinases/genética , RNA Ribossômico 18S/genética , Sensibilidade e Especificidade , Leishmaniose/diagnóstico
14.
Am J Trop Med Hyg ; 108(1): 181-186, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36509047

RESUMO

Class 1 and Class 2 integrons are mobilizable elements able to carry a variety of antibiotic resistance determinants. In the present study, Class 1 and 2 integrons present in 355 pathogenic Escherichia coli (285 diarrheagenic, of these 129 were enteropathogenic, 90 enteroaggregative, 66 enterotoxigenic, and 70 bacteremic) isolated from healthy and ill children under age 5 from periurban areas of Lima, Peru, were characterized. The presence of integrase 1 and 2 was established by polymerase chain reaction (PCR), and variable regions were grouped by PCR-restriction fragment length polymorphism and subsequent sequencing. Antimicrobial resistance was established by disk diffusion. Ninety-seven isolates (27.3%) presented integrase 1, and 16 (4.5%) presented integrase 2 (P < 0.0001); in addition, seven (2.0%) isolates, six diarrheagenic and one bacteremic, presented both integrase genes. The presence of integrase 1 was more frequent among bacteremic isolates (P = 0.0004). Variable regions were amplified in 76/120 (63.3%) isolates with up to 14 gene arrangements. The most prevalent gene cassettes were those encoding dihydrofolate reductases as well as aminoglycoside modifying enzymes. Of note, Class 1 integrons tended to be associated with the presence of extended-spectrum ß-lactamases (ESBLs). A variety of Class 1 and 2 integrons were detected in diarrheagenic and bacteremic E. coli, demonstrating the heterogeneity of variable regions circulating in the area. The association of integrons with ESBLs is worrisome and has an impact on the development of multidrug resistance.


Assuntos
Bacteriemia , Diarreia , Infecções por Escherichia coli , Escherichia coli , Integrons , Criança , Pré-Escolar , Humanos , Antibacterianos/farmacologia , Bacteriemia/epidemiologia , Bacteriemia/genética , Bacteriemia/microbiologia , Diarreia/epidemiologia , Diarreia/genética , Diarreia/microbiologia , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/genética , Integrases/genética , Integrons/genética , Testes de Sensibilidade Microbiana , Peru/epidemiologia
15.
Cell Biochem Biophys ; 80(1): 115-122, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34618304

RESUMO

Angiotensin-converting enzyme (ACE, EC 3.4.15.1) is a significant enzyme that regulates blood pressure. ACE inhibitors are often used in the treatment of hypertension. In this work, ACE was purified and characterized in one step with affinity chromatography from sheep kidneys. ACE was 10305-fold purified and specific activity was 19,075 EU/mg protein. The molecular weight and purity of ACE were found with SDS-PAGE and observed two bands at about 60 kDa and 70 kDa on the gel. The effects of reduced nicotinamide adenine dinucleotide (NADH), an antioxidant compound, on purified ACE activity were also researched. NADH on ACE activity showed an inhibition effect. The inhibition type of NADH was determined to be non-competitive inhibition by the Lineweaver-Burk chart and IC50 and Ki values for NADH were 244.33 and 175.08 µM, respectively. These results suggest that antioxidant substances might be efficient in preventing hypertension.


Assuntos
Rim/enzimologia , NAD , Peptidil Dipeptidase A , Animais , Cromatografia de Afinidade , Peptidil Dipeptidase A/isolamento & purificação , Peptidil Dipeptidase A/metabolismo , Ovinos
16.
J Med Virol ; 94(1): 366-371, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34546584

RESUMO

Co-epidemics happening simultaneously can generate a burden on healthcare systems. The co-occurrence of SARS-CoV-2 with vector-borne diseases (VBD), such as malaria and dengue in resource-limited settings represents an additional challenge to the healthcare systems. Herein, we assessed the coinfection rate between SARS-CoV-2 and VBD to highlight the need to carry out an accurate diagnosis and promote timely measures for these infections in Luanda, the capital city of Angola. This was a cross-sectional study conducted with 105 subjects tested for the SARS-CoV-2 and VBD with a rapid detection test in April 2021. The participants tested positive for SARS-CoV-2 (3.80%), malaria (13.3%), and dengue (27.6%). Low odds related to testing positivity to SARS-CoV-2 or VBD were observed in participants above or equal to 40 years (odds ratio [OR]: 0.60, p = 0.536), while higher odds were observed in male (OR: 1.44, p = 0.392) and urbanized areas (OR: 3.78, p = 0.223). The overall co-infection rate between SARS-CoV-2 and VBD was 11.4%. Our findings showed a coinfection between SARS-CoV-2 with malaria and dengue, which could indicate the need to integrate the screening for VBD in the SARS-CoV-2 testing algorithm and the adjustment of treatment protocols. Further studies are warranted to better elucidate the relationship between COVID-19 and VBD in Angola.


Assuntos
COVID-19/epidemiologia , Coinfecção/epidemiologia , Dengue/epidemiologia , Malária/epidemiologia , Doenças Transmitidas por Vetores/epidemiologia , Adolescente , Adulto , Fatores Etários , Angola/epidemiologia , Anticorpos Antiprotozoários/sangue , Anticorpos Antivirais/sangue , Teste para COVID-19 , Febre de Chikungunya/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , RNA Viral/sangue , SARS-CoV-2/isolamento & purificação , Fatores Sexuais , Adulto Jovem , Infecção por Zika virus/epidemiologia
18.
Int J Clin Pract ; 2022: 4752880, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36567774

RESUMO

Background: Pyogenic liver abscess (PLA) is an uncommon but potentially life-threatening condition. In recent years, advances in diagnostics and management have led to early diagnosis and treatment and decreased mortality. We present recent data from a large series of patients with PLA and examine the trends in the management of PLA over a period of 50 years. Methods: The medical records of all patients admitted to the Shaare Zedek Medical Center, Israel, between January 2011 and December 2021 with a primary or secondary diagnosis of PLA were reviewed retrospectively. Results: : Ninety-five patients with PLA were identified. Thirty-eight (40%) were female. The median patient age was 66 years (range 18-93). The diagnosis of PLA in all patients was confirmed with abdominal computed tomography (CT). In twenty patients (21.1%), PLA was not diagnosed by the initial abdominal US. Most abscesses were right-sided. Biliary tract origin was the most common underlying cause of PLA (n = 57, 60%), followed by cryptogenic etiology (n = 28, 30%). Escherichia coli, Klebsiella pneumoniae, and Streptococcus species were most commonly identified. The most common primary treatment modality was percutaneous drainage (PD), which was performed in 81 patients (85.3%). Fourteen patients (14.7%) were treated medically without intervention, and two patients (2.1%) were treated surgically following a failure of PD. Four patients died as a direct result of PLA. Conclusions: Patients diagnosed with PLA are older, the male predominance is less pronounced, and the offending pathogens are likely to originate from the biliary tract. This study questions the utility of abdominal US as the initial diagnostic imaging in patients with suspected PLA (versus CT) and demonstrates improved outcomes for patients with PLA over the years.


Assuntos
Infecções Bacterianas , Abscesso Hepático Piogênico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Causalidade , Escherichia coli/isolamento & purificação , Hospitalização , Abscesso Hepático Piogênico/diagnóstico , Abscesso Hepático Piogênico/epidemiologia , Abscesso Hepático Piogênico/terapia , Estudos Retrospectivos , Drenagem , Klebsiella pneumoniae/isolamento & purificação , Streptococcus/isolamento & purificação
19.
Onderstepoort J Vet Res ; 89(1): e1-e6, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36546513

RESUMO

Influenza A viruses (IAVs) are typically isolated and cultured by successive passages using 9- to 11-day-old embryonated chicken eggs (ECEs) and in 14-day old ECEs for virus mutational studies. Real-time reverse transcription-polymerase chain reaction tests (RT-PCRs) are commonly used for IAV diagnosis, but virus isolation remains invaluable in terms of its high sensitivity, providing viable isolates for further studies and the ability to distinguish between viable and nonviable virus. Efforts at isolating ostrich-origin IAVs from RT-PCR positive specimens using ECEs have often been unsuccessful, raising the possibility of a species bottleneck, whereby ostrich-adapted IAVs may not readily infect and replicate in ECEs, yet the capacity of an ostrich embryo to support the replication of influenza viruses has not been previously demonstrated. This study describes an optimised method for H5 and H7 subtype IAV isolation and propagation in 28-day old embryonated ostrich eggs (EOEs), the biological equivalent of 14-day old ECEs. The viability of EOEs transported from breeding sites could be maximised by pre-incubating the eggs for 12 to 14 days prior to long-distance transportation. This method applied to studies for ostrich-adapted virus isolation and in ovo studies will enable better understanding of the virus-host interaction in ostriches and the emergence of potentially zoonotic diseases.


Assuntos
Vírus da Influenza A , Struthioniformes , Animais , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/virologia , Zigoto/virologia , Virologia/métodos
20.
BMC Bioinformatics ; 23(1): 551, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536300

RESUMO

BACKGROUND: The genomes of SARS-CoV-2 are classified into variants, some of which are monitored as variants of concern (e.g. the Delta variant B.1.617.2 or Omicron variant B.1.1.529). Proportions of these variants circulating in a human population are typically estimated by large-scale sequencing of individual patient samples. Sequencing a mixture of SARS-CoV-2 RNA molecules from wastewater provides a cost-effective alternative, but requires methods for estimating variant proportions in a mixed sample. RESULTS: We propose a new method based on a probabilistic model of sequencing reads, capturing sequence diversity present within individual variants, as well as sequencing errors. The algorithm is implemented in an open source Python program called VirPool. We evaluate the accuracy of VirPool on several simulated and real sequencing data sets from both Illumina and nanopore sequencing platforms, including wastewater samples from Austria and France monitoring the onset of the Alpha variant. CONCLUSIONS: VirPool is a versatile tool for wastewater and other mixed-sample analysis that can handle both short- and long-read sequencing data. Our approach does not require pre-selection of characteristic mutations for variant profiles, it is able to use the entire length of reads instead of just the most informative positions, and can also capture haplotype dependencies within a single read.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , RNA Viral , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , /virologia
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