Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 110
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nucleic Acids Res ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783079

RESUMO

The Next-Generation (NG) IEDB Tools website (https://nextgen-tools.iedb.org) provides users with a redesigned interface to many of the algorithms for epitope prediction and analysis that were originally released on the legacy IEDB Tools website. The initial release focuses on consolidation of all tools related to HLA class I epitopes (MHC binding, elution, immunogenicity, and processing), making all of these predictions accessible from a single application and allowing for their simultaneous execution with minimal user inputs. Additionally, the PEPMatch tool for identifying highly similar epitopes in a set of curated proteomes, as well as a tool for epitope clustering, are available on the site. The NG Tools site allows users to build data pipelines by sending the output of one tool as input for the next. Over the next several years, all pre-existing IEDB Tools, and any newly developed tools, will be integrated into this new site. Here we describe the philosophy behind the redesign and demonstrate the utility and productivity enhancements that are enabled by the new interface.

2.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34819373

RESUMO

A protracted outbreak of New Delhi metallo-ß-lactamase (NDM)-producing carbapenem-resistant Klebsiella pneumoniae started in Tuscany, Italy, in November 2018 and continued in 2020 and through 2021. To understand the regional emergence and transmission dynamics over time, we collected and sequenced the genomes of 117 extensively drug-resistant, NDM-producing K. pneumoniae isolates cultured over a 20-mo period from 76 patients at several healthcare facilities in southeast Tuscany. All isolates belonged to high-risk clone ST-147 and were typically nonsusceptible to all first-line antibiotics. Albeit sporadic, resistances to colistin, tigecycline, and fosfomycin were also observed as a result of repeated, independent mutations. Genomic analysis revealed that ST-147 isolates circulating in Tuscany were monophyletic and highly genetically related (including a network of 42 patients from the same hospital and sharing nearly identical isolates), and shared a recent ancestor with clinical isolates from the Middle East. While the blaNDM-1 gene was carried by an IncFIB-type plasmid, our investigations revealed that the ST-147 lineage from Italy also acquired a hybrid IncFIB/IncHIB-type plasmid carrying the 16S methyltransferase armA gene as well as key virulence biomarkers often found in hypervirulent isolates. This plasmid shared extensive homologies with mosaic plasmids circulating globally including from ST-11 and ST-307 convergent lineages. Phenotypically, the carriage of this hybrid plasmid resulted in increased siderophore production but did not confer virulence to the level of an archetypical, hypervirulent K. pneumoniae in a subcutaneous model of infection with immunocompetent CD1 mice. Our findings highlight the importance of performing genomic surveillance to identify emerging threats.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Animais , Antibacterianos , Proteínas de Bactérias/genética , Biomarcadores , Carbapenêmicos , Colistina , Biologia Computacional/métodos , Infecção Hospitalar/epidemiologia , Humanos , Itália/epidemiologia , Estimativa de Kaplan-Meier , Funções Verossimilhança , Camundongos , Testes de Sensibilidade Microbiana , Preparações Farmacêuticas , Plasmídeos , Polimorfismo de Nucleotídeo Único , beta-Lactamases/genética
3.
Euro Surveill ; 29(24)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873796

RESUMO

In 2003-2023, amid 5,436 Acinetobacter baumannii isolates collected globally through the Multidrug-Resistant Organism Repository and Surveillance Network, 97 were ST19PAS, 34 of which carbapenem-resistant. Strains (n = 32) sampled after 2019 harboured either bla OXA-23, bla OXA-72, and/or bla NDM-5. Phylogenetic analysis of the 97 isolates and 11 publicly available ST19 genomes revealed three sub-lineages of carbapenemase-producing isolates from mainly Ukraine and Georgia, including an epidemic clone carrying all three carbapenemase genes. Infection control and global surveillance of carbapenem-resistant A. baumannii remain important.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Proteínas de Bactérias , Testes de Sensibilidade Microbiana , beta-Lactamases , beta-Lactamases/genética , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Humanos , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/epidemiologia , Proteínas de Bactérias/genética , Ucrânia/epidemiologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Filogenia , Farmacorresistência Bacteriana Múltipla/genética , República da Geórgia/epidemiologia , Tipagem de Sequências Multilocus
4.
Emerg Infect Dis ; 29(8): 1692-1695, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37406356

RESUMO

Blood and surveillance cultures from an injured service member from Ukraine grew Acinetobacter baumannii, Klebsiella pneumoniae, Enterococcus faecium, and 3 distinct Pseudomonas aeruginosa strains. Isolates were nonsusceptible to most antibiotics and carried an array of antibiotic resistant genes, including carbapenemases (blaIMP-1, blaNDM-1, blaOXA-23, blaOXA-48, blaOXA-72) and 16S methyltransferases (armA and rmtB4).


Assuntos
Acinetobacter baumannii , Militares , Humanos , Ucrânia/epidemiologia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Bactérias/genética , beta-Lactamases/genética , Farmacorresistência Bacteriana Múltipla/genética
5.
J Infect Dis ; 225(1): 146-156, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34161579

RESUMO

BACKGROUND: Plasmodium vivax controlled human malaria infection (PvCHMI) is an important tool for evaluation of drugs, vaccines, and pathologies associated with this parasite. However, there are few data on safety due to limited numbers of PvCHMIs performed. METHODS: We report clinical and laboratory data, including hematological and biochemical profiles and adverse events (AEs), following mosquito bite-induced PvCHMI in malaria-naive study participants. Malaria diagnosis and treatment initiation was based on microscopic analysis of Giemsa-stained slides. Exploratory molecular assays were used to detect parasites using real-time polymerase chain reaction (PCR). RESULTS: AEs were mild to moderate and no study-related severe AEs were observed in any study participants. The majority of symptoms were transient, resolving within 48 hours. Molecular diagnostic methods detected parasitemia in 100% of study participants before malaria diagnosis using microscopy. Of reported AEs, microscopy detected 67%-100%, quantitative PCR 79%-100%, and quantitative real-time reverse-transcription PCR 96%-100% of study participants prior to appearance of symptoms. Almost all symptoms appeared after initiation of treatment, likely as known consequence of drug treatment. CONCLUSIONS: PvCHMI is safe with the majority of infections being detected prior to appearance of clinical symptoms, which can be further alleviated by using sensitive molecular methods for clinical diagnosis. Clinical Trials Registration. NCT01157897.


Assuntos
DNA de Protozoário/isolamento & purificação , Mordeduras e Picadas de Insetos , Malária Vivax/diagnóstico , Malária/diagnóstico , Plasmodium vivax/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , DNA de Protozoário/sangue , Feminino , Humanos , Malária/sangue , Masculino , Pessoa de Meia-Idade , Patologia Molecular , Plasmodium vivax/isolamento & purificação , Adulto Jovem
6.
Clin Infect Dis ; 74(5): 909-912, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34086878

RESUMO

A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.345 variant carrying the E484K mutation was detected in 4 patients with no apparent epidemiological association from a hospital network in upstate New York. Subsequent analysis identified an additional 11 B.1.1.345 variants from this region between December 2020 and February 2021.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Mutação , New York/epidemiologia , SARS-CoV-2/genética
7.
Antimicrob Agents Chemother ; 66(1): e0082421, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34662188

RESUMO

Hospitalized patients are at risk of developing serious multidrug resistant bacterial infections. This risk is heightened in patients who are on mechanical ventilation, are immunocompromised, and/or have chronic comorbidities. We report the case of a 52-year-old critically ill patient with a multidrug resistant Acinetobacter baumannii (MDR-A) respiratory infection who was successfully treated with antibiotics and intravenous and nebulized bacteriophage therapy.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Infecção Hospitalar , Terapia por Fagos , Infecções Respiratórias , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estado Terminal , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Humanos , Pessoa de Meia-Idade , Infecções Respiratórias/tratamento farmacológico
8.
Antimicrob Agents Chemother ; 66(3): e0182121, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34978892

RESUMO

The active metabolites of primaquine, in particular 5-hydroxyprimaquine, likely responsible for the clearance of dormant hypnozoites, are produced through the hepatic CYP450 2D6 (CYP2D6) enzymatic pathway. With the inherent instability of 5-hydroxyprimaquine, a stable surrogate, 5,6-orthoquinone, can now be detected and measured in the urine as part of primaquine pharmacokinetic studies. This study performed CYP450 2D6 genotyping and primaquine pharmacokinetic testing, to include urine 5,6-orthoquinone, in 27 healthy adult Cambodians, as a preliminary step to prepare for future clinical studies assessing primaquine efficacy for Plasmodium vivax infections. The CYP2D6 *10 reduced activity allele was found in 57% of volunteers, and the CYP2D6 genotypes were dominated by *1/*10 (33%) and *10/*10 (30%). Predicted phenotypes were evenly split between Normal Metabolizer (NM) and Intermediate Metabolizer (IM) except for one volunteer with a gene duplication and unclear phenotype, classifying as either IM or NM. Median plasma primaquine (PQ) area under the curve (AUC) was lower in the NM group (460 h*ng/mL) compared to the IM group (561 h*ng/mL), although not statistically significant. Similar to what has been found in the US study, no 5,6-orthoquinone was detected in the plasma. The urine creatinine-corrected 5,6-orthoquinone AUC in the NM group was almost three times higher than in the IM group, with peak measurements (Tmax) at 4 h. Although there is variation among individuals, future studies examining the relationship between the levels of urine 5,6-orthoquinone and primaquine radical cure efficacy could result in a metabolism biomarker predictive of radical cure.


Assuntos
Antimaláricos , Malária Vivax , Adulto , Antimaláricos/farmacocinética , Antimaláricos/uso terapêutico , Povo Asiático , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Humanos , Malária Vivax/tratamento farmacológico , Plasmodium vivax/genética , Primaquina/análogos & derivados , Primaquina/farmacocinética , Primaquina/uso terapêutico
9.
PLoS Comput Biol ; 17(10): e1009459, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613979

RESUMO

Recent technological advances have made the gathering of comprehensive gene expression datasets a commodity. This has shifted the limiting step of transcriptomic studies from the accumulation of data to their analyses and interpretation. The main problem in analyzing transcriptomics data is that the number of independent samples is typically much lower (<100) than the number of genes whose expression is quantified (typically >14,000). To address this, it would be desirable to reduce the gathered data's dimensionality without losing information. Clustering genes into discrete modules is one of the most commonly used tools to accomplish this task. While there are multiple clustering approaches, there is a lack of informative metrics available to evaluate the resultant clusters' biological quality. Here we present a metric that incorporates known ground truth gene sets to quantify gene clusters' biological quality derived from standard clustering techniques. The GECO (Ground truth Evaluation of Clustering Outcomes) metric demonstrates that quantitative and repeatable scoring of gene clusters is not only possible but computationally lightweight and robust. Unlike current methods, it allows direct comparison between gene clusters generated by different clustering techniques. It also reveals that current cluster analysis techniques often underestimate the number of clusters that should be formed from a dataset, which leads to fewer clusters of lower quality. As a test case, we applied GECO combined with k-means clustering to derive an optimal set of co-expressed gene modules derived from PBMC, which we show to be superior to previously generated modules generated on whole-blood. Overall, GECO provides a rational metric to test and compare different clustering approaches to analyze high-dimensional transcriptomic data.


Assuntos
Biologia Computacional/métodos , Leucócitos Mononucleares/metabolismo , Família Multigênica/genética , Transcriptoma/genética , Bases de Dados Factuais , Humanos
10.
Int J Mol Sci ; 23(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35163321

RESUMO

Cannabis is one of the most commonly used recreational drugs worldwide. Rrecent epidemiology studies have linked increased cardiac complications to cannabis use. However, this literature is predominantly based on case incidents and post-mortem investigations. This study elucidates the molecular mechanism of Δ9-tetrahydrocannabinol (THC), and its primary metabolites 11-Hydroxy-Δ9-THC (THC-OH) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH). Treatment of cardiac myocytes with THC-OH and THC-COOH increased cell migration and proliferation (p < 0.05), with no effect on cell adhesion, with higher doses (250-100 ng/mL) resulting in increased cell death and significant deterioration in cellular architecture. Conversely, no changes in cell morphology or viability were observed in response to THC. Expression of key ECM proteins α-SMA and collagen were up-regulated in response to THC-OH and THC-COOH treatments with concomitant modulation of PI3K and MAPK signalling. Investigations in the planarian animal model Polycelis nigra demonstrated that treatments with cannabinoid metabolites resulted in increased protein deposition at transection sites while higher doses resulted in significant lethality and decline in regeneration. These results highlight that the key metabolites of cannabis elicit toxic effects independent of the parent and psychoactive compound, with implications for cardiotoxicity relating to hypertrophy and fibrogenesis.


Assuntos
Cannabis , Alucinógenos , Analgésicos/metabolismo , Animais , Agonistas de Receptores de Canabinoides , Cannabis/metabolismo , Cannabis/toxicidade , Cardiotoxicidade , Dronabinol/toxicidade , Alucinógenos/metabolismo , Miócitos Cardíacos/metabolismo
11.
Antimicrob Agents Chemother ; 65(7): e0015021, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33972237

RESUMO

KPC-82 is a KPC-2 variant identified in a carbapenem-nonsusceptible Citrobacter koseri that confers high-level resistance to ceftazidime-avibactam. Genomic analysis revealed that blaKPC-82 is carried by a chromosomally integrated Tn4401 transposon (disrupting porin gene phoE) and evolved by a 6-nucleotide tandem repeat duplication causing a two-amino-acid insertion (Ser-Asp) within the Ala267-Ser275 loop. Similar to related KPC variants, KPC-82 showed decreased carbapenemase activity when expressed in a heterologous background and remained susceptible to carbapenem/ß-lactamase inhibitor combinations.


Assuntos
Carbapenêmicos , Citrobacter koseri , Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Ceftazidima/farmacologia , Combinação de Medicamentos , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
12.
Int J Mol Sci ; 22(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668403

RESUMO

Cocaine is one of the most widely abused illicit drugs worldwide and has long been recognised as an agent of cardiac dysfunction in numerous cases of drug overdose. Cocaine has previously been shown to up-regulate cytoskeletal rearrangements and morphological changes in numerous tissues; however, previous literature observes such changes primarily in clinical case reports and addiction studies. An investigation into the fundamental cytoskeletal parameters of migration, adhesion and proliferation were studied to determine the cytoskeletal and cytotoxic basis of cocaine in cardiac cells. Treatment of cardiac myocytes with cocaine increased cell migration and adhesion (p < 0.05), with no effect on cell proliferation, except with higher doses eliciting (1-10 µg/mL) its diminution and increase in cell death. Cocaine downregulated phosphorylation of cofilin, decreased expression of adhesion modulators (integrin-ß3) and increased expression of ezirin within three hours of 1 µg/mL treatments. These functional responses were associated with changes in cellular morphology, including alterations in membrane stability and a stellate-like phenotype with less compaction between cells. Higher dose treatments of cocaine (5-10 µg/mL) were associated with significant cardiomyocyte cell death (p < 0.05) and loss of cellular architecture. These results highlight the importance of cocaine in mediating cardiomyocyte function and cytotoxicity associated with the possible loss of intercellular contacts required to maintain normal cell viability, with implications for cardiotoxicity relating to hypertrophy and fibrogenesis.


Assuntos
Cardiotoxicidade/patologia , Cocaína/toxicidade , Citoesqueleto/patologia , Miócitos Cardíacos/patologia , Vasoconstritores/toxicidade , Animais , Cardiotoxicidade/etiologia , Adesão Celular , Movimento Celular , Sobrevivência Celular , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Ratos
13.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32718956

RESUMO

Over the past two decades, Acinetobacter baumannii has emerged as a leading cause of nosocomial infections worldwide. Of particular concern are panresistant strains, leading the World Health Organization (WHO) to designate carbapenem-resistant A. baumannii as a priority 1 (critical) pathogen for research and development of new antibiotics. A key component in supporting this effort is accessibility to diverse and clinically relevant strains for testing. Here, we describe a panel of 100 diverse A. baumannii strains for use in this endeavor. Whole-genome sequencing was performed on 3,505 A. baumannii isolates housed at the Multidrug-Resistant Organism Repository and Surveillance Network. Isolates were cultured from clinical samples at health care facilities around the world between 2001 and 2017. Core-genome multilocus sequence typing and high-resolution single nucleotide polymorphism (SNP)-based phylogenetic analyses were used to select a final panel of 100 strains that captured the genetic diversity of the collection. Comprehensive antibiotic susceptibility testing was also performed on all 100 isolates using 14 clinically relevant antibiotics. The final 100-strain diversity panel contained representative strains from 70 different traditional Pasteur scheme multilocus sequence types, including major epidemic clones. This diversity was also reflected in antibiotic susceptibility and antimicrobial resistance (AMR) gene content, with phenotypes ranging from pansensitive to panresistant, and over 100 distinct AMR gene alleles identified from 32 gene families. This panel provides the most diverse and comprehensive set of A. baumannii strains for use in developing solutions for combating antibiotic resistance. The panel and all available metadata, including genome sequences, will be available to industry and academic institutions and federal and other laboratories free of charge.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Infecção Hospitalar , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Pesquisa
14.
N Engl J Med ; 376(4): 330-341, 2017 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-25830322

RESUMO

BACKGROUND: The worst Ebola virus disease (EVD) outbreak in history has resulted in more than 28,000 cases and 11,000 deaths. We present the final results of two phase 1 trials of an attenuated, replication-competent, recombinant vesicular stomatitis virus (rVSV)-based vaccine candidate designed to prevent EVD. METHODS: We conducted two phase 1, placebo-controlled, double-blind, dose-escalation trials of an rVSV-based vaccine candidate expressing the glycoprotein of a Zaire strain of Ebola virus (ZEBOV). A total of 39 adults at each site (78 participants in all) were consecutively enrolled into groups of 13. At each site, volunteers received one of three doses of the rVSV-ZEBOV vaccine (3 million plaque-forming units [PFU], 20 million PFU, or 100 million PFU) or placebo. Volunteers at one of the sites received a second dose at day 28. Safety and immunogenicity were assessed. RESULTS: The most common adverse events were injection-site pain, fatigue, myalgia, and headache. Transient rVSV viremia was noted in all the vaccine recipients after dose 1. The rates of adverse events and viremia were lower after the second dose than after the first dose. By day 28, all the vaccine recipients had seroconversion as assessed by an enzyme-linked immunosorbent assay (ELISA) against the glycoprotein of the ZEBOV-Kikwit strain. At day 28, geometric mean titers of antibodies against ZEBOV glycoprotein were higher in the groups that received 20 million PFU or 100 million PFU than in the group that received 3 million PFU, as assessed by ELISA and by pseudovirion neutralization assay. A second dose at 28 days after dose 1 significantly increased antibody titers at day 56, but the effect was diminished at 6 months. CONCLUSIONS: This Ebola vaccine candidate elicited anti-Ebola antibody responses. After vaccination, rVSV viremia occurred frequently but was transient. These results support further evaluation of the vaccine dose of 20 million PFU for preexposure prophylaxis and suggest that a second dose may boost antibody responses. (Funded by the National Institutes of Health and others; rVSV∆G-ZEBOV-GP ClinicalTrials.gov numbers, NCT02269423 and NCT02280408 .).


Assuntos
Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Adulto , Anticorpos Antivirais/sangue , Método Duplo-Cego , Vacinas contra Ebola/administração & dosagem , Vacinas contra Ebola/efeitos adversos , Ebolavirus/genética , Ebolavirus/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Doença pelo Vírus Ebola/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Soroconversão , Vacinas Atenuadas/imunologia , Vírus da Estomatite Vesicular Indiana , Proteínas do Envelope Viral/isolamento & purificação , Viremia
15.
Malar J ; 19(1): 336, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938444

RESUMO

BACKGROUND: Malaria remains the top infectious disease threat facing the U.S. military in many forward operating environments. Compliance with malaria chemoprophylaxis remains a critical component in preventing malaria in the deployed Service Member. Studies of previous military operations show that compliance is consistently higher with weekly versus daily dosing regimens. Current FDA approved weekly chemoprophylaxis options have contraindications that can limit prescribing. The combination of chloroquine (CQ) with azithromycin (AZ) has previously been shown to be an efficacious treatment option for malaria, has pharmacokinetics compatible with weekly dosing, and has shown synergy when combined in vitro. METHODS: In this open label study, 18 healthy volunteers, aged 18-50 years (inclusive), were randomly assigned to receive either 300 mg CQ or 300 mg CQ and 2 gm azithromycin (CQAZ) of directly observed therapy, weekly for 3 weeks prior to undergoing mosquito bite challenge with chloroquine-resistant Plasmodium falciparum. Volunteers that remained asymptomatic and had no evidence of parasitaemia continued to receive weekly post-exposure chemoprophylaxis for 3 weeks following malaria challenge. The primary endpoint was the number of volunteers that remained asymptomatic and had no evidence of parasitaemia 28 days after the malaria challenge. RESULTS: All 6 (100%) volunteers randomized to the CQ control group became symptomatic with parasitaemia during the 28-day post-challenge period. Only 1/12 (8.3%) of volunteers in the CQAZ group developed symptoms and parasitaemia during the 28-day post-challenge period. However, after chemoprophylaxis was discontinued an additional 6 volunteers developed parasitaemia between days 28-41 after challenge, with 4 of 6 experiencing symptoms. 80% of subjects in the CQAZ group experienced treatment related gastrointestinal adverse events (including 13% that experienced severe nausea) compared to 38% in the CQ group. A comparison of the pharmacokinetics in the CQAZ group demonstrated higher azithromycin Cmax (p = 0.03) and AUC (p = 0.044) levels in those volunteers who never became parasitaemic compared to those who did. CONCLUSION: Given the high rate of side effects and poor efficacy when administered for 3 weeks before and after challenge, the combination of weekly chloroquine and azithromycin is a suboptimal regimen combination for weekly malaria chemoprophylaxis. Trial registration ClinicalTrials.gov NCT03278808.


Assuntos
Antimaláricos/efeitos adversos , Azitromicina/efeitos adversos , Cloroquina/efeitos adversos , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Adulto , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
J Infect Dis ; 220(11): 1761-1770, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31549155

RESUMO

BACKGROUND: Plasmodium vivax malaria requires a 2-week course of primaquine (PQ) for radical cure. Evidence suggests that the hepatic isoenzyme cytochrome P450 2D6 (CYP2D6) is the key enzyme required to convert PQ into its active metabolite. METHODS: CYP2D6 genotypes and phenotypes of 550 service personnel were determined, and the pharmacokinetics (PK) of a 30-mg oral dose of PQ was measured in 45 volunteers. Blood and urine samples were collected, with PQ and metabolites were measured using ultraperformance liquid chromatography with mass spectrometry. RESULTS: Seventy-six CYP2D6 genotypes were characterized for 530 service personnel. Of the 515 personnel for whom a single phenotype was predicted, 58% had a normal metabolizer (NM) phenotype, 35% had an intermediate metabolizer (IM) phenotype, 5% had a poor metabolizer (PM) phenotype, and 2% had an ultrametabolizer phenotype. The median PQ area under the concentration time curve from 0 to ∞ was lower for the NM phenotype as compared to the IM or PM phenotypes. The novel 5,6-ortho-quinone was detected in urine but not plasma from all personnel with the NM phenotype. CONCLUSION: The plasma PK profile suggests PQ metabolism is decreased in personnel with the IM or PM phenotypes as compared to those with the NM phenotype. The finding of 5,6-ortho-quinone, the stable surrogate for the unstable 5-hydroxyprimaquine metabolite, almost exclusively in personnel with the NM phenotype, compared with sporadic or no production in those with the IM or PM phenotypes, provides further evidence for the role of CYP2D6 in radical cure. CLINICAL TRIALS REGISTRATION: NCT02960568.


Assuntos
Antimaláricos/metabolismo , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Genótipo , Primaquina/metabolismo , Administração Oral , Adolescente , Adulto , Antimaláricos/administração & dosagem , Antimaláricos/farmacocinética , Análise Química do Sangue , Cromatografia Líquida de Alta Pressão , Estudos de Coortes , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Militares , Fenótipo , Plasma/química , Primaquina/administração & dosagem , Primaquina/farmacocinética , Estados Unidos , Urinálise , Urina/química , Adulto Jovem
17.
Infect Immun ; 87(3)2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30559218

RESUMO

Seroepidemiological studies on the prevalence of antibodies to malaria antigens are primarily conducted on individuals from regions of endemicity. It is therefore difficult to accurately correlate the antibody responses to the timing and number of prior malaria infections. This study was undertaken to assess the evolution of antibodies to the dominant surface antigens of Plasmodium vivax and P. falciparum following controlled human malaria infection (CHMI) in malaria-naive individuals. Serum samples from malaria-naive adults, collected before and after CHMI with either P. vivax (n = 18) or P. falciparum (n = 18), were tested for the presence of antibodies to the circumsporozoite protein (CSP) and the 42-kDa fragment of merozoite surface protein 1 (MSP-142) of P. vivax and P. falciparum using an enzyme-linked immunosorbent assay (ELISA). Approximately 1 month following CHMI with either P. vivax or P. falciparum, >60% of subjects seroconverted to homologous CSP and MSP-1. More than 50% of the subjects demonstrated reactivity to heterologous CSP and MSP-142, and a similar proportion of subjects remained seropositive to homologous MSP-142 >5 months after CHMI. Computational analysis provides insight into the presence of cross-reactive responses. The presence of long-lived and heterologous reactivity and its functional significance, if any, need to be taken into account while evaluating malaria exposure in field settings.


Assuntos
Antígenos de Protozoários/imunologia , Eritrócitos/parasitologia , Malária Falciparum/imunologia , Malária Vivax/imunologia , Plasmodium falciparum , Plasmodium vivax , Adolescente , Adulto , Animais , Anopheles/parasitologia , Epitopos de Linfócito B , Feminino , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Mosquitos Vetores/parasitologia , Proteínas de Protozoários/imunologia , Adulto Jovem
18.
Infection ; 47(5): 729-737, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30796628

RESUMO

PURPOSE: Individuals with methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infection (SSTI) can be simultaneously colonized with MRSA on multiple body sites. Using whole genome sequencing (WGS), the intrahost relatedness of MRSA colonization and infection isolates was investigated. METHODS: In the context of a prospective case-control study of SSTI, we analyzed colonization and infection isolates from US Army Infantry trainees with purulent infection due to MRSA. At the time of clinical presentation for SSTI, culture swabs were obtained from the infection site, as well as from the patient's nasal, oral, inguinal, and perianal regions. S. aureus culture and susceptibility was performed by standard methods. DNA from MRSA isolates was extracted and libraries were produced. Sequences were generated on an Illumina MiSeq, sequence reads were assembled, and single nucleotide variant (SNV) data were analyzed. RESULTS: Of 74 trainees with MRSA SSTI, 19 (25.7%) were colonized with MRSA. Ten (52.6%) were colonized on more than one body site. Colonization frequency by anatomic site was as follows: inguinal region (33%), nasal region (30%), perianal region (22%), and oral region (14%). A total of 36 MRSA colonization isolates were characterized. The intrahost median number of SNVs between infection and colonization isolates was 17. Among trainees with recurrent MRSA SSTI, limited intrahost diversity suggests that persistent colonization is a major contributor to recurrence risk. CONCLUSIONS: Among military trainees with MRSA SSTI, genomic characterization of infection and colonization isolates revealed a high degree of strain relatedness. Single acquisition events may account for MRSA colonization and infection in this population.


Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Militares/estatística & dados numéricos , Infecções dos Tecidos Moles/epidemiologia , Infecções Cutâneas Estafilocócicas/epidemiologia , Adolescente , Adulto , Estudos de Casos e Controles , DNA Bacteriano/genética , Genômica , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Risco , Infecções dos Tecidos Moles/microbiologia , Estados Unidos/epidemiologia , Sequenciamento Completo do Genoma , Adulto Jovem
19.
J Urol ; 199(1): 229-236, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28709886

RESUMO

PURPOSE: We evaluated the therapeutic success rate, changes in quality of life and safety of sacral neuromodulation 5 years after InterStim™ implantation. Included in study were subjects with bothersome symptoms of overactive bladder, including urinary urge incontinence and/or urgency-frequency, in whom at least 1 anticholinergic medication failed and 1 medication had not been tried. MATERIALS AND METHODS: Therapeutic success was defined as a urinary urge incontinence or urgency-frequency response of 50% or greater improvement in average leaks or voids per day, or return to normal voiding, defined as fewer than 8 voids per day. Quality of life was evaluated by ICIQ-OABqol (International Consultation on Incontinence Modular Questionnaire). Safety was evaluated through adverse events. RESULTS: Of the 340 subjects who completed the test stimulation 272 had an implant, of whom 91% were female. Mean age was 57 years. At baseline 202 subjects with urinary urge incontinence had a mean ± SD of 3.1 ± 2.7 leaks per day and 189 with urgency-frequency had a mean of 12.6 ± 4.5 voids per day. The 5-year therapeutic success rate was 67% (95% CI 60-74) using modified completers analysis and 82% (95% CI 76-88) using completers analysis. Subjects with urinary urge incontinence had a mean reduction from baseline of 2.0 ± 2.2 leaks per day and subjects with urgency-frequency had a mean reduction of 5.4 ± 4.3 voids per day (each completers analysis p <0.0001). Subjects showed improvement in all ICIQ-OABqol measures (p <0.0001). The most common device related adverse events were an undesirable change in stimulation in 60 of the 272 subjects (22%), implant site pain in 40 (15%) and therapeutic product ineffectiveness in 36 (13%). CONCLUSIONS: This multicenter study shows that sacral neuromodulation had sustained efficacy and quality of life improvements, and an acceptable safety profile through 5 years in subjects with overactive bladder.


Assuntos
Terapia por Estimulação Elétrica/métodos , Plexo Lombossacral/fisiopatologia , Dor Pós-Operatória/epidemiologia , Bexiga Urinária Hiperativa/terapia , Incontinência Urinária de Urgência/terapia , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Estudos Prospectivos , Qualidade de Vida , Fatores de Tempo , Resultado do Tratamento , Bexiga Urinária Hiperativa/fisiopatologia , Incontinência Urinária de Urgência/fisiopatologia
20.
Langmuir ; 34(38): 11335-11346, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30157638

RESUMO

The adsorption and subsequent electrooxidative polymerization of ferriprotoporphyrin IX chloride (hemin; FePPCl) was investigated on highly ordered pyrolytic graphite, glassy carbon, and polycrystalline Pt electrodes using electrochemical atomic force microscopy, first-principles calculations, and cyclic voltammetry. Hemin was shown to readily adsorb to all three surfaces; however, it was more continuous over the carbon surfaces compared to the Pt surface. This disparity in adsorption appears to be a major contributing factor to differences observed between the electrodes following hemin electropolymerization. Despite differences in roughness and morphology, hemin polymerized as a continuous layer over each electrode surface. Periodic density functional theory calculations were used to model FePP (without Cl) on both the Pt(111) and graphite surfaces using the vdW-DF-optPBE functional to account for the dispersion interactions. Our calculations suggest that the FePP molecule chemisorbs to the Pt surface while at the same time exhibiting intramolecular hydrogen bonding between the carboxylic acid groups, which are extended away from the surface. In contrast to FePP-Pt chemisorption, FePP was found to physisorb to graphite. The preferred spin state upon adsorption was found to be S = 2 on Pt(111), whereas on graphite, the high and intermediate spin states were nearly isoenergetic. Additionally, gas-phase calculations suggest that much of the surface roughness observed microscopically for the polymerized porphyrin layer may originate from the nonparallel stacking of porphyrin molecules, which interact with each other by forming four intermolecular hydrogen bonds and through dispersion interactions between the stacked porphyrin rings. Regardless of polymer thickness, the underlying electrode appears to be able to participate in at least some redox processes. This was observed for the hemin-polymerized Pt electrode using the 2H+/H2 redox couple and was suspected to be due to some Pt surface atoms not being specifically coordinated to the hemin molecules and therefore available to react with H+ that was small enough to diffuse through the polymer layer.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA