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1.
Nature ; 600(7888): 279-284, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34837071

RESUMO

Confocal microscopy1 remains a major workhorse in biomedical optical microscopy owing to its reliability and flexibility in imaging various samples, but suffers from substantial point spread function anisotropy, diffraction-limited resolution, depth-dependent degradation in scattering samples and volumetric bleaching2. Here we address these problems, enhancing confocal microscopy performance from the sub-micrometre to millimetre spatial scale and the millisecond to hour temporal scale, improving both lateral and axial resolution more than twofold while simultaneously reducing phototoxicity. We achieve these gains using an integrated, four-pronged approach: (1) developing compact line scanners that enable sensitive, rapid, diffraction-limited imaging over large areas; (2) combining line-scanning with multiview imaging, developing reconstruction algorithms that improve resolution isotropy and recover signal otherwise lost to scattering; (3) adapting techniques from structured illumination microscopy, achieving super-resolution imaging in densely labelled, thick samples; (4) synergizing deep learning with these advances, further improving imaging speed, resolution and duration. We demonstrate these capabilities on more than 20 distinct fixed and live samples, including protein distributions in single cells; nuclei and developing neurons in Caenorhabditis elegans embryos, larvae and adults; myoblasts in imaginal disks of Drosophila wings; and mouse renal, oesophageal, cardiac and brain tissues.


Assuntos
Aprendizado Profundo , Microscopia Confocal/métodos , Microscopia Confocal/normas , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/crescimento & desenvolvimento , Linhagem Celular Tumoral , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Humanos , Discos Imaginais/citologia , Camundongos , Mioblastos/citologia , Especificidade de Órgãos , Análise de Célula Única , Fixação de Tecidos
2.
Antimicrob Agents Chemother ; 66(9): e0049622, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36066241

RESUMO

The CDC's Emerging Infections Program (EIP) conducted population- and laboratory-based surveillance of US carbapenem-resistant Pseudomonas aeruginosa (CRPA) from 2016 through 2018. To characterize the pathotype, 1,019 isolates collected through this project underwent antimicrobial susceptibility testing and whole-genome sequencing. Sequenced genomes were classified using the seven-gene multilocus sequence typing (MLST) scheme and a core genome (cg)MLST scheme was used to determine phylogeny. Both chromosomal and horizontally transmitted mechanisms of carbapenem resistance were assessed. There were 336 sequence types (STs) among the 1,019 sequenced genomes, and the genomes varied by an average of 84.7% of the cgMLST alleles used. Mutations associated with dysfunction of the porin OprD were found in 888 (87.1%) of the genomes and were correlated with carbapenem resistance, and a machine learning model incorporating hundreds of genetic variations among the chromosomal mechanisms of resistance was able to classify resistant genomes. While only 7 (0.1%) isolates harbored carbapenemase genes, 66 (6.5%) had acquired non-carbapenemase ß-lactamase genes, and these were more likely to have OprD dysfunction and be resistant to all carbapenems tested. The genetic diversity demonstrates that the pathotype includes a variety of strains, and clones previously identified as high-risk make up only a minority of CRPA strains in the United States. The increased carbapenem resistance in isolates with acquired non-carbapenemase ß-lactamase genes suggests that horizontally transmitted mechanisms aside from carbapenemases themselves may be important drivers of the spread of carbapenem resistance in P. aeruginosa.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Centers for Disease Control and Prevention, U.S. , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Porinas/genética , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/epidemiologia , Estados Unidos/epidemiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
3.
Antimicrob Agents Chemother ; 65(7): e0082521, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33972240

RESUMO

Infections caused by extended-spectrum-ß-lactamase (ESBL)-producing Escherichia coli are a significant cause of morbidity and health care costs. Globally, the prevailing clonal type is ST131 in association with the blaCTX-M-15 ß-lactamase gene. However, other ESBLs, such as blaCTX-M-14 and blaCTX-M-27, can also be prevalent in some regions. We identified ST38 ESBL-producing E. coli from different regions in the United States which carry blaCTX-M-27 embedded on two distinct plasmid types, suggesting the potential emergence of new ESBL lineages.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Proteínas de Escherichia coli/genética , Humanos , Plasmídeos/genética , Estados Unidos , beta-Lactamases/genética
4.
J Clin Microbiol ; 58(9)2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32493782

RESUMO

Pseudomonas aeruginosa is an opportunistic human pathogen that frequently causes health care-associated infections (HAIs). Due to its metabolic diversity and ability to form biofilms, this Gram-negative nonfermenting bacterium can persist in the health care environment, which can lead to prolonged HAI outbreaks. We describe the creation of a core genome multilocus sequence typing (cgMLST) scheme to provide a stable platform for the rapid comparison of P. aeruginosa isolates using whole-genome sequencing (WGS) data. We used a diverse set of 58 complete P. aeruginosa genomes to curate a set of 4,440 core genes found in each isolate, representing ∼64% of the average genome size. We then expanded the alleles for each gene using 1,991 contig-level genome sequences. The scheme was used to analyze genomes from four historical HAI outbreaks to compare the phylogenies generated using cgMLST to those of other means (traditional MLST, pulsed-field gel electrophoresis [PFGE], and single-nucleotide variant [SNV] analysis). The cgMLST scheme provides sufficient resolution for analyzing individual outbreaks, as well as the stability for comparisons across a variety of isolates encountered in surveillance studies, making it a valuable tool for the rapid analysis of P. aeruginosa genomes.


Assuntos
Genoma Bacteriano , Pseudomonas aeruginosa , Atenção à Saúde , Surtos de Doenças , Genoma Bacteriano/genética , Humanos , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Pseudomonas aeruginosa/genética
5.
Am J Kidney Dis ; 74(5): 610-619, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31375298

RESUMO

RATIONALE & OBJECTIVE: Contaminated water and other fluids are increasingly recognized to be associated with health care-associated infections. We investigated an outbreak of Gram-negative bloodstream infections at 3 outpatient hemodialysis facilities. STUDY DESIGN: Matched case-control investigations. SETTING & PARTICIPANTS: Patients who received hemodialysis at Facility A, B, or C from July 2015 to November 2016. EXPOSURES: Infection control practices, sources of water, dialyzer reuse, injection medication handling, dialysis circuit priming, water and dialysate test findings, environmental reservoirs such as wall boxes, vascular access care practices, pulsed-field gel electrophoresis, and whole-genome sequencing of bacterial isolates. OUTCOMES: Cases were defined by a positive blood culture for any Gram-negative bacteria drawn July 1, 2015 to November 30, 2016 from a patient who had received hemodialysis at Facility A, B, or C. ANALYTICAL APPROACH: Exposures in cases and controls were compared using matched univariate conditional logistic regression. RESULTS: 58 cases of Gram-negative bloodstream infection occurred; 48 (83%) required hospitalization. The predominant organisms were Serratia marcescens (n=21) and Pseudomonas aeruginosa (n=12). Compared with controls, cases had higher odds of using a central venous catheter for dialysis (matched odds ratio, 54.32; lower bound of the 95% CI, 12.19). Facility staff reported pooling and regurgitation of waste fluid at recessed wall boxes that house connections for dialysate components and the effluent drain within dialysis treatment stations. Environmental samples yielded S marcescens and P aeruginosa from wall boxes. S marcescens isolated from wall boxes and case-patients from the same facilities were closely related by pulsed-field gel electrophoresis and whole-genome sequencing. We identified opportunities for health care workers' hands to contaminate central venous catheters with contaminated fluid from the wall boxes. LIMITATIONS: Limited patient isolates for testing, on-site investigation occurred after peak of infections. CONCLUSIONS: This large outbreak was linked to wall boxes, a previously undescribed source of contaminated fluid and biofilms in the immediate patient care environment.


Assuntos
Bacteriemia/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Diálise Renal/efeitos adversos , Idoso , Bacteriemia/microbiologia , Feminino , Seguimentos , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Retrospectivos , Estados Unidos/epidemiologia
6.
Biophys J ; 112(9): 1975-1983, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28494967

RESUMO

The lack of physiological recordings from Caenorhabditis elegans embryos stands in stark contrast to the comprehensive anatomical and gene expression datasets already available. Using light-sheet fluorescence microscopy to address the challenges associated with functional imaging at this developmental stage, we recorded calcium dynamics in muscles and neurons and developed analysis strategies to relate activity and movement. In muscles, we found that the initiation of twitching was associated with a spreading calcium wave in a dorsal muscle bundle. Correlated activity in muscle bundles was linked with early twitching and eventual coordinated movement. To identify neuronal correlates of behavior, we monitored brainwide activity with subcellular resolution and identified a particularly active cell associated with muscle contractions. Finally, imaging neurons of a well-defined adult motor circuit, we found that reversals in the eggshell correlated with calcium transients in AVA interneurons.


Assuntos
Caenorhabditis elegans/embriologia , Caenorhabditis elegans/metabolismo , Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Locomoção/fisiologia , Atividade Motora/fisiologia , Animais , Escherichia coli , Processamento de Imagem Assistida por Computador , Microscopia de Fluorescência , Músculos/embriologia , Músculos/metabolismo , Neurônios/metabolismo
7.
Can J Microbiol ; 60(12): 857-63, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25409940

RESUMO

Pseudomonas aeruginosa establishes life-long chronic infections in the cystic fibrosis (CF) lung by utilizing various adaptation strategies. Some of these strategies include altering metabolic pathways to utilize readily available nutrients present in the host environment. The airway sputum contains various host-derived nutrients that can be utilized by P. aeruginosa, including phosphatidylcholine, a major component of lung surfactant. Pseudomonas aeruginosa can degrade phosphatidylcholine to glycerol and fatty acids to increase the availability of usable carbon sources in the CF lung. In this study, we show that some CF-adapted P. aeruginosa isolates utilize glycerol more efficiently as a carbon source than nonadapted isolates. Furthermore, a mutation in a gene required for glycerol utilization impacts the production of several virulence factors in both acute and chronic isolates of P. aeruginosa. Taken together, the results suggest that interference with this metabolic pathway may have potential therapeutic benefits.


Assuntos
Fibrose Cística/microbiologia , Glicerol/metabolismo , Glicerolfosfato Desidrogenase/metabolismo , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Fatores de Virulência/biossíntese , Adaptação Fisiológica , Meios de Cultura , Genes Bacterianos , Glicerolfosfato Desidrogenase/genética , Humanos , Mutação , Oligopeptídeos/biossíntese , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , Piocianina/biossíntese
9.
Contemp Clin Trials ; 131: 107273, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37380021

RESUMO

BACKGROUND: Oxaliplatin is a key chemotherapeutic agent in the treatment of local and metastatic gastrointestinal (GI) malignancies. Dose density and treatment adherence can be limited by chemotherapy-induced peripheral neuropathy (CIPN). Early research suggests CIPN incidence and severity may be mitigated by acupuncture, but rigorous data in GI oncology patients is limited. Here, we describe the protocol of a randomized, waitlist-controlled pilot study testing the use of preemptive of acupuncture plus acupressure to decrease CIPN and chemotherapy-related toxicities. METHODS: Patients with a GI malignancy (n = 56) with planned 5-fluorouracil (5-FU) and oxaliplatin IV (FOLFOX, FOLFIRINOX) every 2 weeks are being recruited. Additional concurrent anti-neoplastic agents may be used. Enrolled patients are randomized 1:1 to a 3-month intervention of Arm A: acupuncture with acupressure and standard-of-care treatment, or Arm B: standard-of-care alone. In Arm A, on days 1 and 3 of each chemotherapy cycle a standardized acupuncture protocol is administered and patients are taught self-acupressure to perform daily between chemotherapy treatments. Patients in both arms are given standard-of-care oral and peripheral (hands/feet) ice chip cryotherapy during oxaliplatin administration. CIPN and other symptoms are assessed at baseline, 6 weeks, and 3 months from registration. The primary endpoint is CIPN severity at 3 months (EORTC-CIPN 20). Additional endpoints evaluate CIPN incidence (CTCAE, Neuropen, tuning fork); incidence of pain, fatigue, nausea, oral dysesthesia, and anxiety; and feasibility (recruitment, retention, adherence, acceptability). If warranted, trial results will inform the design of a multi-center trial to expand testing of the intervention to a larger patient cohort.


Assuntos
Acupressão , Terapia por Acupuntura , Antineoplásicos , Neoplasias Gastrointestinais , Neoplasias Pancreáticas , Doenças do Sistema Nervoso Periférico , Humanos , Oxaliplatina/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Estudos de Viabilidade , Antineoplásicos/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle , Terapia por Acupuntura/efeitos adversos , Terapia por Acupuntura/métodos , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/etiologia , Crioterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
10.
Am J Infect Control ; 51(1): 70-77, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35909003

RESUMO

BACKGROUND: Carbapenem-resistant Enterobacterales (CRE) are usually healthcare-associated but are also emerging in the community. METHODS: Active, population-based surveillance was conducted to identify case-patients with cultures positive for Enterobacterales not susceptible to a carbapenem (excluding ertapenem) and resistant to all third-generation cephalosporins tested at 8 US sites from January 2012 to December 2015. Medical records were used to classify cases as health care-associated, or as community-associated (CA) if a patient had no known health care risk factors and a culture was collected <3 days after hospital admission. Enterobacterales isolates from selected cases were submitted to CDC for whole genome sequencing. RESULTS: We identified 1499 CRE cases in 1194 case-patients; 149 cases (10%) in 139 case-patients were CA. The incidence of CRE cases per 100,000 population was 2.96 (95% CI: 2.81, 3.11) overall and 0.29 (95% CI: 0.25, 0.35) for CA-CRE. Most CA-CRE cases were in White persons (73%), females (84%) and identified from urine cultures (98%). Among the 12 sequenced CA-CRE isolates, 5 (42%) harbored a carbapenemase gene. CONCLUSIONS: Ten percent of CRE cases were CA; some isolates from CA-CRE cases harbored carbapenemase genes. Continued CRE surveillance in the community is critical to monitor emergence outside of traditional health care settings.


Assuntos
Carbapenêmicos , Infecções por Enterobacteriaceae , Feminino , Estados Unidos/epidemiologia , Humanos , Carbapenêmicos/farmacologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae , beta-Lactamases/genética , Instalações de Saúde , Fatores de Risco , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana
11.
Analyst ; 137(6): 1351-62, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22262038

RESUMO

We introduce a label-free approach for sensing polymerase reactions on deoxyribonucleic acid (DNA) using a chelator-modified silicon-on-insulator field-effect transistor (SOI-FET) that exhibits selective and reversible electrical response to pyrophosphate anions. The chemical modification of the sensor surface was designed to include rolling-circle amplification (RCA) DNA colonies for locally enhanced pyrophosphate (PPi) signal generation and sensors with immobilized chelators for capture and surface-sensitive detection of diffusible reaction by-products. While detecting arrays of enzymatic base incorporation reactions is typically accomplished using optical fluorescence or chemiluminescence techniques, our results suggest that it is possible to develop scalable and portable PPi-specific sensors and platforms for broad biomedical applications such as DNA sequencing and microbe detection using surface-sensitive electrical readout techniques.


Assuntos
DNA Polimerase Dirigida por DNA/metabolismo , DNA/química , DNA/metabolismo , Difosfatos/análise , Técnicas Eletroquímicas , Transistores Eletrônicos , Sequência de Bases , Técnicas Biossensoriais , Quelantes/química , DNA Polimerase Dirigida por DNA/química , Dados de Sequência Molecular , Estrutura Molecular , Silanos/química , Silício/química , Propriedades de Superfície
12.
J Spinal Cord Med ; 35(2): 107-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22525324

RESUMO

BACKGROUND: Functional electrical stimulation (FES) has been regularly used to offset several negative body composition and metabolic adaptations following spinal cord injury (SCI). However, the outcomes of many FES trials appear to be controversial and incoherent. OBJECTIVE: To document the potential consequences of several factors (e.g. pain, spasms, stress and lack of dietary control) that may have attenuated the effects on body composition and metabolic profile despite participation in 21 weeks of FES training. PARTICIPANT: A 29-year-old man with T6 complete SCI participated in 21 weeks of FES, 4 days per week. METHODS: Prior to and following training, the participant performed arm-crank-graded exercise testing to measure peak VO(2). Tests conducted included anthropometrics and dual energy X-ray absorptiometry body composition assessments, resting energy expenditure, plasma lipid profiles and intravenous glucose tolerance tests. RESULTS: The participant frequently reported increasing pain, stress and poor eating habits. VO(2) peak decreased by 2.4 ml/kg/minute, body mass increased by 8.5 kg, and body mass index increased from 25 to 28 kg/m(2). Waist and abdominal circumferences increased by 2-4 cm, while %fat mass increased by 5.5%. Absolute increases in fat mass and fat-free mass of 8.4 and 1 kg, respectively, were reported. Fasting and peak plasma glucose increased by 12 and 14.5%, while lipid panel profiles were negatively impacted. CONCLUSION: Failure to control for the listed negative emerging factors may obscure the expected body composition and metabolic profile adaptations anticipated from FES training.


Assuntos
Terapia por Estimulação Elétrica/métodos , Traumatismos da Medula Espinal/terapia , Absorciometria de Fóton , Adulto , Aminoácidos , Composição Corporal/fisiologia , Índice de Massa Corporal , Cromo , Metabolismo Energético , Terapia por Exercício/métodos , Humanos , Masculino , Metaboloma , Ácidos Nicotínicos
13.
J Intell ; 10(4)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36278607

RESUMO

Do individuals learn more effectively when given progressive or variable problem-solving experience, relative to consistent problem-solving experience? We investigated this question using a Rubik's Cube paradigm. Participants were randomly assigned to a progression-order condition, where they practiced solving three progressively more difficult Rubik's Cubes (i.e., 2 × 2 × 2 to 3 × 3 × 3 to 4 × 4 × 4), a variable-order condition, where they practiced solving three Rubik's Cubes of varying difficulty (e.g., 3 × 3 × 3 to 2 × 2 × 2 to 4 × 4 × 4), or a consistent-order condition, where they consistently practiced on three 5 × 5 × 5 Rubik's Cubes. All the participants then attempted a 5 × 5 × 5 Rubik's Cube test. We tested whether variable training is as effective as progressive training for near transfer of spatial skills and whether progressive training is superior to consistent training. We found no significant differences in performance across conditions. Participants' fluid reasoning predicted 5 × 5 × 5 Rubik's Cube test performance regardless of training condition.

14.
Microb Drug Resist ; 28(6): 645-653, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35639112

RESUMO

Healthcare-associated carbapenem-resistant Acinetobacter baumannii (CRAB) infections are a serious threat associated with global epidemic clones and a variety of carbapenemase gene classes. In this study, we describe the molecular epidemiology, including whole-genome sequencing analysis and antimicrobial susceptibility profiles of 92 selected, nonredundant CRAB collected through public health efforts in the United States from 2013 to 2017. Among the 92 isolates, the Oxford (OX) multilocus sequence typing scheme identified 30 sequence types (STs); the majority of isolates (n = 59, 64%) represented STs belonging to the international clonal complex 92 (CC92OX). Among these, ST208OX (n = 21) and ST281OX (n = 20) were the most common. All isolates carried an OXA-type carbapenemase gene, comprising 20 alleles. Ninety isolates (98%) encoded an intrinsic OXA-51-like enzyme; 67 (73%) harbored an additional acquired blaOXA gene, most commonly blaOXA-23 (n = 45; 49%). Compared with isolates harboring only intrinsic oxacillinase genes, acquired blaOXA gene presence was associated with higher prevalence of resistance and a higher median minimum inhibitory concentration to the carbapenem imipenem (64 µg/mL vs. 8 µg/mL), and antibiotics from other drug classes, including penicillin, aminoglycosides, cephalosporins, and polymyxins. These data illustrate the wide distribution of CC92OX and high prevalence of acquired blaOXA carbapenemase genes among CRAB in the United States.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Infecção Hospitalar , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecção Hospitalar/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Estados Unidos/epidemiologia , beta-Lactamases/genética
15.
Appl Biosaf ; 27(2): 84-91, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36776750

RESUMO

Background: Burkholderia pseudomallei is a Tier 1 overlap select agent and subject to the select agent regulations (42 CFR §73 and 9 CFR §121). It is a gram-negative, motile, soil saprophyte, and the etiologic agent of melioidosis. B. pseudomallei infection can produce systemic illness and can be fatal in the absence of appropriate treatment. Laboratory exposures involving this organism may occur when appropriate containment measures are not employed. Current disease treatment inadequacies and the risk factors associated with melioidosis make this an agent of primary concern in research, commercial, and clinical laboratory environments. Results: This study presents data reported to Centers for Disease Control and Prevention (CDC), Division of Select Agents and Toxins for releases involving B. pseudomallei in 2017-2019 that occurred in Biosafety Level (BSL)-2 and BSL-3 laboratories. Fifty-one Animal and Plant Health Inspection Service (APHIS)/CDC Form 3 release reports led to the medical surveillance of 275 individuals. Entities offered post-exposure prophylaxis to ∼76% of the individuals impacted in the presented events. Summary: Laboratory safety can be improved by implementing appropriate safety precautions to minimize exposures. Most of the incidents discussed in this evidence-based report occurred during work conducted in the absence of primary containment. None of the releases resulted in illness, death, or transmission to or among workers, nor was there transmission outside of a laboratory into the surrounding environment or community. Effective risk assessment and management strategies coupled with standard and special microbiological policies and procedures can result in reduced exposures and improved safety at facilities.

16.
Microb Drug Resist ; 28(4): 389-397, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35172110

RESUMO

Carbapenem-resistant Enterobacterales (CRE) are a growing public health concern due to resistance to multiple antibiotics and potential to cause health care-associated infections with high mortality. Carbapenemase-producing CRE are of particular concern given that carbapenemase-encoding genes often are located on mobile genetic elements that may spread between different organisms and species. In this study, we performed phenotypic and genotypic characterization of CRE collected at eight U.S. sites participating in active population- and laboratory-based surveillance of carbapenem-resistant organisms. Among 421 CRE tested, the majority were isolated from urine (n = 349, 83%). Klebsiella pneumoniae was the most common organism (n = 265, 63%), followed by Enterobacter cloacae complex (n = 77, 18%) and Escherichia coli (n = 50, 12%). Of 419 isolates analyzed by whole genome sequencing, 307 (73%) harbored a carbapenemase gene; variants of blaKPC predominated (n = 299, 97%). The occurrence of carbapenemase-producing K. pneumoniae, E. cloacae complex, and E. coli varied by region; the predominant sequence type within each genus was ST258, ST171, and ST131, respectively. None of the carbapenemase-producing CRE isolates displayed resistance to all antimicrobials tested; susceptibility to amikacin and tigecycline was generally retained.


Assuntos
Carbapenêmicos , Infecções por Enterobacteriaceae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Enterobacter , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/epidemiologia , Escherichia coli/genética , Humanos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Estados Unidos , beta-Lactamases/genética
17.
Infect Control Hosp Epidemiol ; 43(11): 1586-1594, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35156596

RESUMO

OBJECTIVE: The incidence of infections from extended-spectrum ß-lactamase (ESBL)-producing Enterobacterales (ESBL-E) is increasing in the United States. We describe the epidemiology of ESBL-E at 5 Emerging Infections Program (EIP) sites. METHODS: During October-December 2017, we piloted active laboratory- and population-based (New York, New Mexico, Tennessee) or sentinel (Colorado, Georgia) ESBL-E surveillance. An incident case was the first isolation from normally sterile body sites or urine of Escherichia coli or Klebsiella pneumoniae/oxytoca resistant to ≥1 extended-spectrum cephalosporin and nonresistant to all carbapenems tested at a clinical laboratory from a surveillance area resident in a 30-day period. Demographic and clinical data were obtained from medical records. The Centers for Disease Control and Prevention (CDC) performed reference antimicrobial susceptibility testing and whole-genome sequencing on a convenience sample of case isolates. RESULTS: We identified 884 incident cases. The estimated annual incidence in sites conducting population-based surveillance was 199.7 per 100,000 population. Overall, 800 isolates (96%) were from urine, and 790 (89%) were E. coli. Also, 393 cases (47%) were community-associated. Among 136 isolates (15%) tested at the CDC, 122 (90%) met the surveillance definition phenotype; 114 (93%) of 122 were shown to be ESBL producers by clavulanate testing. In total, 111 (97%) of confirmed ESBL producers harbored a blaCTX-M gene. Among ESBL-producing E. coli isolates, 52 (54%) were ST131; 44% of these cases were community associated. CONCLUSIONS: The burden of ESBL-E was high across surveillance sites, with nearly half of cases acquired in the community. EIP has implemented ongoing ESBL-E surveillance to inform prevention efforts, particularly in the community and to watch for the emergence of new ESBL-E strains.


Assuntos
Infecções por Escherichia coli , Infecções por Klebsiella , Humanos , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Escherichia coli/genética , Testes de Sensibilidade Microbiana , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico
18.
Biomed Microdevices ; 13(2): 335-44, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21203849

RESUMO

Over the last decade, field-effect transistors (FETs) with nanoscale dimensions have emerged as possible label-free biological and chemical sensors capable of highly sensitive detection of various entities and processes. While significant progress has been made towards improving their sensitivity, much is yet to be explored in the study of various critical parameters, such as the choice of a sensing dielectric, the choice of applied front and back gate biases, the design of the device dimensions, and many others. In this work, we present a process to fabricate nanowire and nanoplate FETs with Al(2)O(3) gate dielectrics and we compare these devices with FETs with SiO(2) gate dielectrics. The use of a high-k dielectric such as Al(2)O(3) allows for the physical thickness of the gate dielectric to be thicker without losing sensitivity to charge, which then reduces leakage currents and results in devices that are highly robust in fluid. This optimized process results in devices stable for up to 8 h in fluidic environments. Using pH sensing as a benchmark, we show the importance of optimizing the device bias, particularly the back gate bias which modulates the effective channel thickness. We also demonstrate that devices with Al(2)O(3) gate dielectrics exhibit superior sensitivity to pH when compared to devices with SiO(2) gate dielectrics. Finally, we show that when the effective electrical silicon channel thickness is on the order of the Debye length, device response to pH is virtually independent of device width. These silicon FET sensors could become integral components of future silicon based Lab on Chip systems.


Assuntos
Óxido de Alumínio/química , Nanofios/química , Transistores Eletrônicos , Impedância Elétrica , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Silício/química
19.
Infect Control Hosp Epidemiol ; 42(6): 722-730, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33234179

RESUMO

BACKGROUND: Sink drains in healthcare facilities may provide an environment for antimicrobial-resistant microorganisms, including carbapenemase-producing Klebsiella pneumoniae (CPKP). METHODS: We investigated the colonization of a biofilm consortia by CPKP in a model system simulating a sink-drain P-trap. Centers for Disease Control (CDC) biofilm reactors (CBRs) were inoculated with microbial consortia originally recovered from 2 P-traps collected from separate patient rooms (designated rooms A and B) in a hospital. Biofilms were grown on stainless steel (SS) or polyvinyl chloride (PVC) coupons in autoclaved municipal drinking water (ATW) for 7 or 28 days. RESULTS: Microbial communities in model systems (designated CBR-A or CBR-B) were less diverse than communities in respective P-traps A and B, and they were primarily composed of ß and γ Proteobacteria, as determined using 16S rRNA community analysis. Following biofilm development CBRs were inoculated with either K. pneumoniae ST45 (ie, strain CAV1016) or K. pneumoniae ST258 KPC+ (ie, strain 258), and samples were collected over 21 days. Under most conditions tested (CBR-A: SS, 7-day biofilm; CBR-A: PVC, 28-day biofilm; CBR-B: SS, 7-day and 28-day biofilm; CBR-B: PVC, 28-day biofilm) significantly higher numbers of CAV1016 were observed compared to 258. CAV1016 showed no significant difference in quantity or persistence based on biofilm age (7 days vs 28 days) or substratum type (SS vs PVC). However, counts of 258 were significantly higher on 28-day biofilms and on SS. CONCLUSIONS: These results suggest that CPKP persistence in P-trap biofilms may be strain specific or may be related to the type of P-trap material or age of the biofilm.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Klebsiella pneumoniae , Biofilmes , Carbapenêmicos/farmacologia , Humanos , Klebsiella pneumoniae/genética , RNA Ribossômico 16S
20.
Trop Med Infect Dis ; 6(4)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34698287

RESUMO

Project Vigilancia de Embarazadas con Zika (VEZ), an intensified surveillance of pregnant women with symptoms of the Zika virus disease (ZVD) in Colombia, aimed to evaluate the relationship between symptoms of ZVD during pregnancy and adverse pregnancy, birth, and infant outcomes and early childhood neurodevelopmental outcomes. During May-November 2016, pregnant women in three Colombian cities who were reported with symptoms of ZVD to the national surveillance system, or with symptoms of ZVD visiting participating clinics, were enrolled in Project VEZ. Data from maternal and pediatric (up to two years of age) medical records were abstracted. Available maternal specimens were tested for the presence of the Zika virus ribonucleic acid and/or anti-Zika virus immunoglobulin antibodies. Of 1213 enrolled pregnant women with symptoms of ZVD, 1180 had a known pregnancy outcome. Results of the Zika virus laboratory testing were available for 569 (48.2%) pregnancies with a known pregnancy outcome though testing timing varied and was often distal to the timing of symptoms; 254 (21.5% of the whole cohort; 44.6% of those with testing results) were confirmed or presumptive positive for the Zika virus infection. Of pregnancies with a known outcome, 50 (4.2%) fetuses/infants had Zika-associated brain or eye defects, which included microcephaly at birth. Early childhood adverse neurodevelopmental outcomes were more common among those with Zika-associated birth defects than among those without and more common among those with laboratory evidence of a Zika virus infection compared with the full cohort. The proportion of fetuses/infants with any Zika-associated brain or eye defect was consistent with the proportion seen in other studies. Enhancements to Colombia's existing national surveillance enabled the assessment of adverse outcomes associated with ZVD in pregnancy.

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