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1.
Microbiol Spectr ; 12(4): e0388523, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38451098

RESUMO

This manuscript describes the development of a streamlined, cost-effective laboratory workflow to meet the demands of increased whole genome sequence (WGS) capacity while achieving mandated quality metrics. From 2020 to 2021, the Wadsworth Center Bacteriology Laboratory (WCBL) used a streamlined workflow to sequence 5,743 genomes that contributed sequence data to nine different projects. The combined use of the QIAcube HT, Illumina DNA Prep using quarter volume reactions, and the NextSeq allowed the WCBL to process all samples that required WGS while also achieving a median turn-around time of 7 days (range 4 to 10 days) and meeting minimum sequence quality requirements. Public Health Laboratories should consider implementing these methods to aid in meeting testing requirements within budgetary restrictions. IMPORTANCE: Public Health Laboratories that implement whole genome sequencing (WGS) technologies may struggle to find the balance between sample volume and cost effectiveness. We present a method that allows for sequencing of a variety of bacterial isolates in a cost-effective manner. This report provides specific strategies to implement high-volume WGS, including an innovative, low-cost solution utilizing a novel quarter volume sequencing library preparation. The methods described support the use of high-throughput DNA extraction and WGS within budgetary constraints, strengthening public health responses to outbreaks and disease surveillance.


Assuntos
Análise de Custo-Efetividade , Saúde Pública , Objetivos , Sequenciamento Completo do Genoma/métodos , DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Genoma Bacteriano
2.
Foodborne Pathog Dis ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38452173

RESUMO

Shiga toxin-producing Escherichia coli (STEC) are an important cause of bacterial enteric infection. STEC strains cause serious human gastrointestinal disease, which may result in life-threatening complications such as hemolytic uremic syndrome. They have the potential to impact public health due to diagnostic challenges of identifying non-O157 strains in the clinical laboratory. The Wadsworth Center (WC), the public health laboratory of the New York State Department of Health, has isolated and identified non-O157 STEC for decades. A shift from initially available enzyme immunoassay testing to culture-independent diagnostic tests (CIDTs) has increased the uptake of testing at clinical microbiology laboratories. This testing change has resulted in an increased number of specimen submissions to WC. During a 12-year period between 2011 and 2022, WC received 5037 broths and/or stool specimens for STEC confirmation from clinical microbiology laboratories. Of these, 3992 were positive for Shiga toxin genes (stx1 and/or stx2) by real-time PCR. Furthermore, culture methods were utilized to isolate, identify, and characterize 2925 STEC from these primary specimens. Notably, WC observed a >200% increase in the number of STEC specimens received in 2021-2022 compared with 2011-2012 and an 18% increase in the number of non-O157 STEC identified using the same methodologies. During the past decade, the WC testing algorithm has been updated to manage the increase in specimens received, while also navigating the novel COVID-19 pandemic, which took priority over other testing for a period of time. This report summarizes updated methods for confirmation, surveillance, and outbreak detection of STEC and describes findings that may be related to our algorithm updates and the increased use of CIDTs, which is starting to elucidate the true incidence of non-O157 STEC.

3.
Lancet ; 402 Suppl 1: S93, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37997140

RESUMO

BACKGROUND: Following low incidence of invasive group A streptococcal (iGAS) infections during the COVID-19 pandemic, marked increases were noted in many countries during 2022, particularly in children. In November 2022, severe presentations of lower respiratory tract infections (LRTIs), including empyema, were notified by clinicians across the UK. UKHSA investigated this rise with the aim of informing clinical management and public health response. METHODS: We undertook a case-series analysis using multiple routine data sources, exempted from ethics approval or patient consent. We identified iGAS cases in England in children younger than 15 years with an LRTI reported between Oct 1 and Dec 21, 2022, using UKHSA laboratory surveillance data (GAS detected in LRT specimens) and notifications by clinicians and Health Protection Teams (HPTs). Symptoms, diagnoses, health-care interactions, and outcome (death or recovery) data were obtained from HPT case management notes, the National Child Mortality Database, and the NHS Digital Emergency Care Dataset. FINDINGS: We identified 147 cases of LRTI iGAS in children across England (77 [52%] male, 70 [48%] female; median age 4 years [IQR 2-6]). Predominant ethnicities were White (74 [65%] of 113 with known ethnicity) and Asian (18 [16%] of 113). Most reported symptoms were fever (90 [75%] of 120 children with ≥1 symptom) and cough (60 [50%] of 120), and 71 (48%) of all 147 children had a diagnosed respiratory viral coinfection (most commonly hMPV and RSV). 127 (86%) of children attended an emergency department, 31% (n=36/114 with onset date) at least twice within 21 days after symptom onset. 37 (25%) of 147 children died, with a median time from symptom onset to death of 4 days (IQR 3-7). Of 32 children with sample dates, 16 (84%) were tested for GAS on or after the day they died. Over half of deaths (21 [57%] of 37 deaths) occurred in the community after rapid deterioration, of whom 18 had previous contact with health-care services documented. INTERPRETATION: The UK saw an unusual rise in iGAS LRTIs in children in late 2022. One in four cases died, over half in the community. Non-specific symptoms, viral symptoms, or positive virology might have lowered suspicion of bacterial infection. Although the use of multiple available data sources expedited the analysis, varying data completeness limited interpretation. Our study highlights the need for earlier detection and identification of effective measures to prevent death. FUNDING: None.


Assuntos
Infecções Respiratórias , Infecções Estreptocócicas , Criança , Humanos , Masculino , Feminino , Pré-Escolar , Pandemias , Infecções Estreptocócicas/epidemiologia , Infecções Respiratórias/epidemiologia , Inglaterra/epidemiologia , Streptococcus pyogenes , Sistema Respiratório
4.
Lancet Public Health ; 8(10): e766-e775, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37777286

RESUMO

BACKGROUND: In July, 2022, an increase in diphtheria cases caused by toxigenic Corynebacterium diphtheriae (C diphtheriae) was reported among asylum seekers arriving by small boats to England. Rising case numbers presented challenges for case and contact management in initial reception centres, prompting changes to national guidance and implementation of population-based control measures. This study aimed to describe the outbreak of toxigenic C diphtheriae among asylum seekers arriving by small boats to England during 2022 by use of national surveillance data. METHODS: We undertook a descriptive epidemiological analysis of cases of toxigenic C diphtheriae among asylum seekers arriving by small boats to England during 2022, incorporating genomic sequencing data, antibiotic susceptibility testing results, and epidemiological data obtained through the UK Health Security Agency's national enhanced surveillance programme. Health Protection Teams conducted risk assessments, and operational data (including details regarding offer and uptake of antibiotics and vaccinations) were obtained from National Health Service partners supporting the intervention programme. FINDINGS: In 2022, C diphtheriae isolates from 86 asylum seekers arriving by small boats were submitted to the National Reference Laboratory for confirmation and testing. Toxigenic C diphtheriae was confirmed for 72 (84%) cases and one individual with typical diphtheritic lesions but from whom no C diphtheriae was isolated from clinical swabs was also included as a probable case, resulting in 73 cases of diphtheria. 71 (97%) were male, 39 (53%) were younger than 18 years, and 36 (49%) presented with cutaneous diphtheria. The prevalence of diphtheria was highest among Afghans (1·3%) compared with all other nationalities (<0·1%). Local antibiotic susceptibility testing identified six cases with a macrolide resistant strain. INTERPRETATION: The increase in diphtheria coincided with a high volume of asylum seekers arriving by small boats to England during 2022, and subsequently increased clinical awareness of the disease among this population. Long-term disruption to vaccination programmes in origin countries along with barriers to accessing health care along migrant routes puts asylum seekers arriving by small boats at risk of disease. With arrivals expected to continue in 2023, the UK Health Security Agency has recommended continuation of population-based control measures in England until October, 2023, subject to ongoing review. FUNDING: The UK Health Security Agency.


Assuntos
Corynebacterium diphtheriae , Difteria , Refugiados , Masculino , Humanos , Feminino , Corynebacterium diphtheriae/genética , Difteria/epidemiologia , Difteria/prevenção & controle , Difteria/microbiologia , Saúde Pública , Medicina Estatal , Corynebacterium/genética , Inglaterra/epidemiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Surtos de Doenças/prevenção & controle
5.
Front Public Health ; 11: 1206056, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457262

RESUMO

Mycobacterium tuberculosis complex (MTBC) infections are treated with combinations of antibiotics; however, these regimens are not as efficacious against multidrug and extensively drug resistant MTBC. Phenotypic (growth-based) drug susceptibility testing on slow growing bacteria like MTBC requires many weeks to months to complete, whereas sequencing-based approaches can predict drug resistance (DR) with reduced turnaround time. We sought to develop a multiplexed, targeted next generation sequencing (tNGS) assay that can predict DR and can be performed directly on clinical respiratory specimens. A multiplex PCR was designed to amplify a group of thirteen full-length genes and promoter regions with mutations known to be involved in resistance to first- and second-line MTBC drugs. Long-read amplicon libraries were sequenced with Oxford Nanopore Technologies platforms and high-confidence resistance mutations were identified in real-time using an in-house developed bioinformatics pipeline. Sensitivity, specificity, reproducibility, and accuracy of the tNGS assay was assessed as part of a clinical validation study. In total, tNGS was performed on 72 primary specimens and 55 MTBC-positive cultures and results were compared to clinical whole genome sequencing (WGS) performed on paired patient cultures. Complete or partial susceptibility profiles were generated from 82% of smear positive primary specimens and the resistance mutations identified by tNGS were 100% concordant with WGS. In addition to performing tNGS on primary clinical samples, this assay can be used to sequence MTBC cultures mixed with other mycobacterial species that would not yield WGS results. The assay can be effectively implemented in a clinical/diagnostic laboratory with a two to three day turnaround time and, even if batched weekly, tNGS results are available on average 15 days earlier than culture-derived WGS results. This study demonstrates that tNGS can reliably predict MTBC drug resistance directly from clinical specimens or cultures and provide critical information in a timely manner for the appropriate treatment of patients with DR tuberculosis.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Sequenciamento de Nucleotídeos em Larga Escala , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose/diagnóstico
6.
Microbiol Spectr ; : e0431722, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36975781

RESUMO

Vancomycin-resistant Staphylococcus aureus (VRSA) is a human pathogen of significant public health concern. Although the genome sequences of individual VRSA isolates have been published over the years, very little is known about the genetic changes of VRSA within a patient over time. A total of 11 VRSA, 3 vancomycin-resistant enterococci (VRE), and 4 methicillin-resistant S. aureus (MRSA) isolates, collected over a period of 4.5 months in 2004 from a patient in a long-term-care facility in New York State, were sequenced. A combination of long- and short-read sequencing technologies was used to obtain closed assemblies for chromosomes and plasmids. Our results indicate that a VRSA isolate emerged as the result of the transfer of a multidrug resistance plasmid from a coinfecting VRE to an MRSA isolate. The plasmid then integrated into the chromosome via homologous recombination mediated between two regions derived from remnants of transposon Tn5405. Once integrated, the plasmid underwent further reorganization in one isolate, while two others lost the staphylococcal cassette chromosome mec element (SCCmec) determinant that confers methicillin-resistance. The results presented here explain how a few recombination events can lead to multiple pulsed-field gel electrophoresis (PFGE) patterns that could be mistaken for vastly different strains. A vanA gene cluster that is located on a multidrug resistance plasmid that is integrated into the chromosome could result in the continuous propagation of resistance, even in the absence of selective pressure from antibiotics. The genome comparison presented here sheds light on the emergence and evolution of VRSA within a single patient that will enhance our understanding VRSA genetics. IMPORTANCE High-level vancomycin-resistant Staphylococcus aureus (VRSA) began to emerge in the United States in 2002 and has since then been reported worldwide. Our study reports the closed genome sequences of multiple VRSA isolates obtained in 2004 from a single patient in New York State. Our results show that the vanA resistance locus is located on a mosaic plasmid that confers resistance to multiple antibiotics. In some isolates, this plasmid integrated into the chromosome via homologous recombination between two ant(6)-sat4-aph(3') antibiotic resistance loci. This is, to our knowledge, the first report of a chromosomal vanA locus in VRSA; the effect of this integration event on MIC values and plasmid stability in the absence of antibiotic selection remains poorly understood. These findings highlight the need for a better understanding of the genetics of the vanA locus and plasmid maintenance in S. aureus to address the increase of vancomycin resistance in the health care setting.

7.
Emerg Infect Dis ; 28(10): 2082-2086, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35960543

RESUMO

After community transmission of monkeypox virus was identified in Europe, interviews of 45 case-patients from England indicated transmission in international sexual networks of gay and bisexual men since April 2022. Interventions targeting sex-on-premises venues, geospatial dating applications, and sexual health services are likely to be critical for outbreak control.


Assuntos
Infecções por HIV , Mpox , Minorias Sexuais e de Gênero , Bissexualidade , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Monkeypox virus , Comportamento Sexual
8.
Mol Cell Probes ; 61: 101786, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34863914

RESUMO

Since 2005, the Wadsworth Center (WC) has provided molecular testing on cerebrospinal fluid (CSF) and whole blood specimens in close collaboration with epidemiologists in New York State and New York City. In this study, we analyzed 10 years of data to demonstrate the significant value of utilizing molecular methods to assess patient specimens for etiologic agents of bacterial meningitis. A comprehensive molecular testing algorithm to detect and serotype/serogroup bacterial agents known to cause bacterial meningitis (Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus agalactiae) has evolved, and retrospective specimen testing has been essential for each improvement. Over a ten-year span from 2010 to 2019 the WC received 831 specimens from 634 patients with suspected bacterial meningitis. Real-time PCR was positive for at least one of the agents in 223 (27%) specimens from 183 patients (29%). Of the 223 positives, 146 (66%) were further characterized by real-time PCR into serogroup/serotype. Additionally, examination of 131 paired specimens of CSF and whole blood from the same patients found better detection in CSF, but whole blood is a useful alternative for diagnosis when CSF is not available. For specimens initially PCR-negative, 16S rDNA Sanger sequencing was requested by the submitter for 146 cases resulting in the identification of bacterial agents in an additional 24 (16%) specimens. In a retrospective study, Next Generation Sequencing (NGS) was evaluated for the detection of pathogens in 53 previously tested PCR-negative CSF specimens and identified bacteria in 14 (26%) specimens. This molecular testing algorithm has provided clinicians a diagnosis when culture is negative with the potential to guide therapy. It has also aided public health in determining when antibiotic prophylaxis was needed, augmented surveillance data to yield a fuller picture of community prevalence, and highlighted gaps in the spectrum of agents that cause bacterial meningitis.


Assuntos
Meningites Bacterianas , Neisseria meningitidis , Técnicas de Laboratório Clínico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/microbiologia , Neisseria meningitidis/genética , New York , Saúde Pública , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Sorotipagem
9.
Appl Environ Microbiol ; 87(16): e0058021, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34085864

RESUMO

Since 1978, the New York State Department of Health's public health laboratory, Wadsworth Center (WC), in collaboration with epidemiology and environmental partners, has been committed to providing comprehensive public health testing for Legionella in New York. Statewide, clinical case counts have been increasing over time, with the highest numbers identified in 2017 and 2018 (1,022 and 1,426, respectively). Over the course of more than 40 years, the WC Legionella testing program has continuously implemented improved testing methods. The methods utilized have transitioned from solely culture-based methods for organism recovery to development of a suite of reference testing services, including identification and characterization by PCR and pulsed-field gel electrophoresis (PFGE). In the last decade, whole-genome sequencing (WGS) has further refined the ability to link outbreak strains between clinical specimens and environmental samples. Here, we review Legionnaires' disease outbreak investigations during this time period, including comprehensive testing of both clinical and environmental samples. Between 1978 and 2017, 60 outbreaks involving clinical and environmental isolates with matching PFGE patterns were detected in 49 facilities from the 157 investigations at 146 facilities. However, 97 investigations were not solved due to the lack of clinical or environmental isolates or PFGE matches. We found 69% of patient specimens from New York State (NYS) were outbreak associated, a much higher rate than observed in other published reports. The consistent application of new cutting-edge technologies and environmental regulations has resulted in successful investigations resulting in remediation efforts. IMPORTANCE Legionella, the causative agent of Legionnaires' disease (LD), can cause severe respiratory illness. In 2018, there were nearly 10,000 cases of LD reported in the United States (https://www.cdc.gov/legionella/fastfacts.html; https://wonder.cdc.gov/nndss/static/2018/annual/2018-table2h.html), with actual incidence believed to be much higher. About 10% of patients with LD will die, and as high as 90% of patients diagnosed will be hospitalized. As Legionella is spread predominantly through engineered building water systems, identifying sources of outbreaks by assessing environmental sources is key to preventing further cases LD.


Assuntos
Legionella/isolamento & purificação , Doença dos Legionários/microbiologia , Surtos de Doenças , Água Doce/microbiologia , Humanos , Legionella/classificação , Legionella/genética , Doença dos Legionários/diagnóstico , Doença dos Legionários/epidemiologia , New York/epidemiologia , Abastecimento de Água
11.
J Clin Microbiol ; 57(7)2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31068414

RESUMO

Whole-genome sequencing (WGS) of pathogens from pure culture provides unparalleled accuracy and comprehensive results at a cost that is advantageous compared with traditional diagnostic methods. Sequencing pathogens directly from a primary clinical specimen would help circumvent the need for culture and, in the process, substantially shorten the time to diagnosis and public health reporting. Unfortunately, this approach poses significant challenges because of the mixture of multiple sequences from a complex fecal biomass. The aim of this project was to develop a proof of concept protocol for the sequencing and genotyping of Shiga toxin-producing Escherichia coli (STEC) directly from stool specimens. We have developed an enrichment protocol that reliably achieves a substantially higher DNA yield belonging to E. coli, which provides adequate next-generation sequencing (NGS) data for downstream bioinformatics analysis. A custom bioinformatics pipeline was created to optimize and remove non-E. coli reads, assess the STEC versus commensal E. coli population in the samples, and build consensus sequences based on population allele frequency distributions. Side-by-side analysis of WGS from paired STEC isolates and matched primary stool specimens reveal that this method can reliably be implemented for many clinical specimens to directly genotype STEC and accurately identify clusters of disease outbreak when no STEC isolate is available for testing.


Assuntos
Infecções por Escherichia coli/diagnóstico , Fezes/microbiologia , Doenças Transmitidas por Alimentos/diagnóstico , Genoma Bacteriano/genética , Técnicas de Diagnóstico Molecular/métodos , Escherichia coli Shiga Toxigênica/isolamento & purificação , DNA Bacteriano/genética , Monitoramento Epidemiológico , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética
12.
J Environ Health ; 80(8): 8-12, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29780175

RESUMO

We investigated an outbreak of eight Legionnaires' disease cases among persons living in an urban residential community of 60,000 people. Possible environmental sources included two active cooling towers (air-conditioning units for large buildings) <1 km from patient residences, a market misting system, a community-wide water system used for heating and cooling, and potable water. To support a timely public health response, we used real-time polymerase chain reaction (PCR) to identify Legionella DNA in environmental samples within hours of specimen collection. We detected L. pneumophila serogroup 1 DNA only at a power plant cooling tower, supporting the decision to order remediation before culture results were available. An isolate from a power plant cooling tower sample was indistinguishable from a patient isolate by pulsed-field gel electrophoresis, suggesting the cooling tower was the outbreak source. PCR results were available <1 day after sample collection, and culture results were available as early as 5 days after plating. PCR is a valuable tool for identifying Legionella DNA in environmental samples in outbreak settings.

13.
J Tissue Eng Regen Med ; 11(1): 295-305, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-24945362

RESUMO

Skin substitutes for repair of dermal wounds are deficient in functional elastic fibres. We report that the content of insoluble elastin in the dermis of cultured human skin can be increased though the use of two approaches that enhance elastogenesis by dermal fibroblasts, forced expression of versican variant V3, which lacks glycosaminoglycan (GAG) chains, and forced expression of versican antisense to decrease levels of versican variant V1 with GAG chains. Human dermal fibroblasts transduced with V3 or anti-versican were cultured under standard conditions over a period of 4 weeks to produce dermal sheets, with growth enhanced though multiple seedings for the first 3 weeks. Human keratinocytes, cultured in supplemented media, were added to the 4-week dermal sheets and the skin layer cultured for a further week. At 5 weeks, keratinocytes were multilayered and differentiated, with desmosome junctions thoughout and keratin deposits in the upper squamous layers. The dermal layer was composed of layered fibroblasts surrounded by extracellular matrix of collagen bundles and, in control cultures, small scattered elastin deposits. Forced expression of V3 and versican antisense slowed growth, decreased versican V1 expression, increased tropoelastin expression and/or the deposition of large aggregates of insoluble elastin in the dermal layer, and increased tissue stiffness, as measured by nano-indentation. Skin sheets were also cultured on Endoform Dermal Template™, the biodegradable wound dressing made from the lamina propria of sheep foregut. Skin structure and the enhanced deposition of elastin by forced expression of V3 and anti-versican were preserved on this supportive substrate. Copyright © 2014 John Wiley & Sons, Ltd.


Assuntos
Técnicas de Cultura de Células/métodos , Tecido Elástico/metabolismo , Elastina/metabolismo , Engenharia Tecidual/métodos , Tropoelastina/metabolismo , Versicanas/metabolismo , Animais , Materiais Biocompatíveis/química , Células Cultivadas , Colágeno/metabolismo , Derme/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Glicosaminoglicanos/metabolismo , Humanos , Queratinócitos/citologia , Queratinas/química , Mucosa , Ratos , Ovinos , Pele/metabolismo , Cicatrização
14.
Exp Cell Res ; 347(1): 241-249, 2016 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-27539660

RESUMO

The stroma, the middle layer of the cornea, is a connective tissue making up most of the corneal thickness. The stromal extracellular matrix (ECM) consists of highly organised lamellae which are made up of tightly packed fibrils primarily composed of collagens type I and V. This layer is interspersed with keratocytes, mesenchymal cells of neural crest origin. We have previously shown that adult corneal keratocytes exhibit phenotypic plasticity and can be induced into a neuronal phenotype. In the current study we evaluated the potential of keratocytes to produce collagen type II via phenotypic reprogramming with exogenous chondrogenic factors. The cornea presents a challenge to tissue engineers owing to its high level of organisation and the phenotypic instability of keratocytes. Traditional approaches based on a scar model do not support the engineering of functional stromal tissue. Type II collagen is not found in the adult cornea but is reported to be expressed during corneal development, raising the possibility of using such an approach to regenerate the corneal ECM. Keratocytes in culture and within intact normal and diseased tissue were induced to produce collagen type II upon treatment with transforming growth factor Beta3 (TGFß3) and dexamethasone. In vivo treatment of rat corneas also resulted in collagen type II deposition and a threefold increase in corneal hardness and elasticity. Furthermore, the treatment of corneas and subsequent deposition of collagen type II did not cause opacity, fibrosis or scarring. The induction of keratocytes with specific exogenous factors and resulting deposition of type II collagen in the stroma can potentially be controlled by withdrawal of the factors. This might be a promising new approach for in vivo corneal regeneration strategies aimed at increasing corneal integrity in diseases associated with weakened ectatic corneal tissue such as keratoconus.


Assuntos
Ceratócitos da Córnea/metabolismo , Matriz Extracelular/metabolismo , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Cartilagem/metabolismo , Células Cultivadas , Condrogênese , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Ceratócitos da Córnea/efeitos dos fármacos , Opacidade da Córnea , Dexametasona/farmacologia , Módulo de Elasticidade , Matriz Extracelular/efeitos dos fármacos , Dureza , Humanos , Masculino , Especificidade de Órgãos/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Fator de Crescimento Transformador beta3/metabolismo , Fator de Crescimento Transformador beta3/farmacologia
15.
Endocrinology ; 157(9): 3550-61, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27384302

RESUMO

A positive association between fat and bone mass is maintained through a network of signaling molecules. Clinical studies found that the circulating levels of adiponectin, a peptide secreted from adipocytes, are inversely related to visceral fat mass and bone mineral density, and it has been suggested that adiponectin contributes to the coupling between fat and bone. Our study tested the hypothesis that adiponectin affects bone tissue by comparing the bone phenotype of wild-type and adiponectin-knockout (APN-KO) female mice between the ages of 8-37 weeks. Using a longitudinal study design, we determined body composition and bone density using dual energy x-ray absorptiometry. In parallel, groups of animals were killed at different ages and bone properties were analyzed by microcomputed tomography, dynamic histomorphometry, 3-point bending test, nanoindentation, and computational modelling. APN-KO mice had reduced body fat and decreased whole-skeleton bone mineral density. Microcomputed tomography analysis identified reduced cortical area fraction and average cortical thickness in APN-KO mice in all the age groups and reduced trabecular bone volume fraction only in young APN-KO mice. There were no major differences in bone strength and material properties between the 2 groups. Taken together, our results demonstrate a positive effect of adiponectin on bone geometry and density in our mouse model. Assuming adiponectin has similar effects in humans, the low circulating levels of adiponectin associated with increased fat mass are unlikely to contribute to the parallel increase in bone mass. Therefore, adiponectin does not appear to play a role in the coupling between fat and bone tissue.


Assuntos
Adiponectina/fisiologia , Densidade Óssea , Osso Cortical/fisiologia , Adipócitos/fisiologia , Adiposidade , Animais , Células da Medula Óssea/fisiologia , Osso Esponjoso/fisiologia , Simulação por Computador , Feminino , Camundongos Knockout , Modelos Biológicos
16.
Diagn Microbiol Infect Dis ; 83(3): 305-11, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26341704

RESUMO

Confirmed and probable cases of invasive Neisseria meningitidis (Nm) infection are reportable in New York City. We conducted a study to identify Nm among culture-negative reports of bacterial and viral meningitis. During the study period, 262 reports of suspected meningitis were eligible. Cerebrospinal fluid (CSF) specimens from 138 patients were obtained for testing. No Nm cases were detected. Results from real-time polymerase chain reaction and 16S on CSF specimens were concordant with hospital microbiology findings in 80%; however, other pathogenic organisms were detected in 14 culture-negative specimens. New York City's surveillance system appears to be effective at capturing cases of Nm meningitis. Nucleic acid testing is useful for detecting the presence of bacterial DNA when antibiotic therapy precedes lumbar puncture or bacterial cultures are negative. It remains unanswered whether culture-negative cases of Nm bacteremia are being missed by reportable disease surveillance.


Assuntos
Meningite Meningocócica/epidemiologia , Meningite Meningocócica/microbiologia , Técnicas de Diagnóstico Molecular/métodos , Neisseria meningitidis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas Bacteriológicas/métodos , Líquido Cefalorraquidiano/microbiologia , Criança , Pré-Escolar , DNA Bacteriano/química , DNA Bacteriano/genética , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Neisseria meningitidis/genética , Cidade de Nova Iorque/epidemiologia , RNA Ribossômico 16S/genética , Adulto Jovem
17.
Int J Syst Evol Microbiol ; 65(Pt 6): 1877-1882, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25792366

RESUMO

Eight independent isolates of a Gram-reaction-negative, non-motile rod, were recovered from clinical specimens of New York State patients between the years 2005 and 2013. Four of these isolates were characterized in a taxonomic study using a polyphasic approach that involved phenotypic, phylogenetic and genotypic methodologies. Based on 16S rRNA gene sequence similarity and phylogenetic analysis, the closest relative type strain of the isolates is Paracoccus sphaerophysae HAMBI 3106T (97.7  % 16S rRNA gene sequence similarity). Among the four isolates, the 16S rRNA gene sequence similarity is 100 %. In silico genomic comparisons, including average nucleotide identity (ANI) and the genome-to-genome distance calculator (GGDC), were used as an alternative to DNA-DNA hybridization in this study to support designation of the four isolates as a novel species of the genus Paracoccus. Mass spectrometry profiles were also obtained for the novel isolates using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The predominant cellular fatty acids of the novel isolates were C18 : 1ω7c and C18 : 0. Biochemical analysis and morphological characteristics further contribute to designation of the four isolates as a novel species of the genus Paracoccus, for which the name Paracoccus sanguinis sp. nov. is proposed. The type strain is 05503T( = DSM 29303T = LMG 28451T).


Assuntos
Paracoccus/classificação , Filogenia , Idoso , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , New York , Hibridização de Ácido Nucleico , Paracoccus/genética , Paracoccus/isolamento & purificação , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
FEBS J ; 280(21): 5337-49, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23837532

RESUMO

The class I phosphatidylinositol 3-kinases (PtdIns3Ks) mediate the effects of many hormones and growth factors on a wide range of cellular processes, and activating mutations or gene amplifications of class I PtdIns3K isoforms are known to contribute to oncogenic processes in a range of tumours. Consequently, a number of small-molecule PtdIns3K inhibitors are under development and in clinical trial. The central signalling role of PtdIns3K in many cellular processes suggests there will be on-target side effects associated with the use of these agents. To gain insights into what these might be we investigated the effect of extended daily dosing of eight small-molecule inhibitors of class Ia PtdIns3Ks. Animals were characterized in metabolic cages to analyse food intake, oxygen consumption and movement. Insulin tolerance and body composition were analysed at the end of the experiment, the latter using EchoMRI. Bone volume and strength was assessed by micro-CT and three-point bending, respectively. Surprisingly, after sustained dosing with pan-PtdIns3K inhibitors and selective inhibitors of the p110α isoform there was a resolution of the impairments in insulin tolerance observed in drug-naïve animals treated with the same drugs. However, pan-PtdIns3K inhibitors and selective inhibitors of the p110α have deleterious effects on animal growth, animal behaviour and bone volume and strength. Together, these findings identify a range of on target effects of PtdIns3K inhibitors and suggest use of these drugs in humans may have important adverse effects on metabolism, body composition, behaviour and skeletal health.


Assuntos
Comportamento Animal/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Glucose/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Metabolismo Basal/efeitos dos fármacos , Índice de Massa Corporal , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/patologia , Ingestão de Alimentos , Imidazóis/farmacologia , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Consumo de Oxigênio/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolinas/farmacologia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
19.
J Biomech ; 45(10): 1775-82, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22648144

RESUMO

This study uses a nanoindentation technique to examine variations in the local mechanical properties of porcine femoral cortical bone under hydrated conditions. Bone specimens from three age groups (6, 12 and 42 months), representing developing bone, ranging from young to mature animals, were tested on the longitudinal and transverse cross-sectional surfaces. Elastic modulus and hardness of individual lamellae within bone's microstructure: laminar bone, interstitial bone, and osteons, were measured. Both the elastic modulus and hardness increased with age. However, the magnitudes of these increases were different for each microstructural component. The longitudinal moduli were higher than the transverse moduli. Dehydrated samples were also tested to allow a comparison with hydrated samples and these resulted in higher moduli and hardness than the hydrated samples. Again, the degree of variation was different for each microstructural component. These results indicate that the developmental changes in bone have different rates of mechanical change within each microstructural component.


Assuntos
Envelhecimento/fisiologia , Desenvolvimento Ósseo/fisiologia , Fêmur , Estresse Fisiológico/fisiologia , Animais , Módulo de Elasticidade/fisiologia , Fêmur/fisiopatologia , Fêmur/ultraestrutura , Testes de Dureza , Suínos
20.
Int J Syst Evol Microbiol ; 62(Pt 2): 322-329, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21421928

RESUMO

Twelve independent isolates of a gram-positive, endospore-forming rod were recovered from clinical specimens in New York State, USA, and from raw milk in Flanders, Belgium. The 16S rRNA gene sequences for all isolates were identical. The closest species with a validly published name, based on 16S rRNA gene sequence, is Sporosarcina koreensis (97.13 % similarity). DNA-DNA hybridization studies demonstrate that the new isolates belong to a species distinct from their nearest phylogenetic neighbours. The partial sequences of the 23S rRNA gene for the novel strains and their nearest neighbours also provide support for the novel species designation. Maximum-likelihood phylogenetic analysis of the 16S rRNA gene sequences confirmed that the new isolates are in the genus Sporosarcina. The predominant menaquinone is MK-7, the peptidoglycan has the type A4α L-Lys-Gly-D-Glu, and the polar lipids consist of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant fatty acids are iso-C(14 : 0), iso-C(15 : 0) and anteiso-C(15 : 0). In addition, biochemical and morphological analyses support designation of the twelve isolates as representatives of a single new species within the genus Sporosarcina, for which the name Sporosarcina newyorkensis sp. nov. (type strain 6062(T)  = DSM 23544(T)  = CCUG 59649(T)  = LMG 26022(T)) is proposed.


Assuntos
Infecções por Bactérias Gram-Positivas/microbiologia , Leite/microbiologia , Sporosarcina/classificação , Sporosarcina/isolamento & purificação , Adulto , Idoso de 80 Anos ou mais , Animais , Técnicas de Tipagem Bacteriana , Bélgica/epidemiologia , Bovinos , Feminino , Genes de RNAr , Infecções por Bactérias Gram-Positivas/epidemiologia , Bacilos Gram-Positivos Formadores de Endosporo/classificação , Bacilos Gram-Positivos Formadores de Endosporo/genética , Bacilos Gram-Positivos Formadores de Endosporo/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , New York/epidemiologia , Hibridização de Ácido Nucleico , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Sporosarcina/genética , Sporosarcina/fisiologia
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