Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Environ Microbiol Rep ; 16(4): e13319, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39096033

RESUMO

Freshwater samples (n = 199) were obtained from 41 sites with contrasting land-uses (avian, low impact, dairy, urban, sheep and beef, and mixed sheep, beef and dairy) and the E. coli phylotype of 3980 isolates (20 per water sample enrichment) was determined. Eight phylotypes were identified with B1 (48.04%), B2 (14.87%) and A (14.79%) the most abundant. Escherichia marmotae (n = 22), and Escherichia ruysiae (n = 1), were rare (0.68%) suggesting that these environmental strains are unlikely to confound water quality assessments. Phylotypes A and B1 were overrepresented in dairy and urban sites (p < 0.0001), whilst B2 were overrepresented in low impact sites (p < 0.0001). Pathogens ((Salmonella, Campylobacter, Cryptosporidium or Giardia) and the presence of diarrhoeagenic E. coli-associated genes (stx and eae) were detected in 89.9% (179/199) samples, including 80.5% (33/41) of samples with putative non-recent faecal inputs. Quantitative PCR to detect microbial source tracking targets from human, ruminant and avian contamination were concordant with land-use type and E. coli phylotype abundance. This study demonstrated that a potential recreational health risk remains where pathogens occurred in water samples with low E. coli concentration, potential non-recent faecal sources, low impact sites and where human, ruminant and avian faecal sources were absent.


Assuntos
Escherichia coli , Água Doce , Saúde Pública , Qualidade da Água , Nova Zelândia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/classificação , Água Doce/microbiologia , Animais , Humanos , Microbiologia da Água , Filogenia , Fezes/microbiologia , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Cryptosporidium/classificação , Giardia/genética , Giardia/isolamento & purificação , Giardia/classificação
2.
J Microbiol Methods ; 220: 106909, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38432551

RESUMO

Escherichia coli are widely used by water quality managers as Fecal Indicator Bacteria, but current quantification methods do not differentiate them from benign, environmental Escherichia species such as E. marmotae (formerly named cryptic clade V) or E. ruysiae (cryptic clades III and IV). Reliable and specific techniques for their identification are required to avoid confounding microbial water quality assessments. To address this, a multiplex droplet digital PCR (ddPCR) assay targeting lipB (E. coli and E. ruysiae) and bglC (E. marmotae) was designed. The ddPCR performance was assessed using in silico analysis; genomic DNA from 40 local, international, and reference strains of target and non-target coliforms; and spiked water samples in a range relevant to water quality managers (1 to 1000 cells/100 mL). Results were compared to an analogous quantitative PCR (qPCR) and the Colilert method. Both PCR assays showed excellent sensitivity with a limit of detection of 0.05 pg/µL and 0.005 pg/µl for ddPCR and qPCR respectively, and of quantification of 0.5 pg/µL of genomic DNA. The ddPCR allowed differentiation and quantification of three Escherichia species per run by amplitude multiplexing and showed a high concordance with concentrations measured by Colilert once proportional bias was accounted for. In silico specificity testing underlined the possibility to further detect and distinguish Escherichia cryptic clade VI. Finally, the applicability of the ddPCR was successfully tested on environmental water samples where E. marmotae and E. ruysiae potentially confound E. coli counts based on the Most Probable Number method, highlighting the utility of this novel ddPCR as an efficient and rapid discriminatory test to improve water quality assessments.


Assuntos
Bactérias , Escherichia coli , Reação em Cadeia da Polimerase em Tempo Real/métodos , Qualidade da Água , DNA
3.
Microbiol Resour Announc ; 13(3): e0100723, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38376223

RESUMO

Escherichia coli is often used as a fecal indicator bacterium for water quality monitoring. We report the draft genome sequences of 500 Escherichia isolates including newly described Escherichia species, namely Escherichia marmotae, Escherichia ruysiae, and Escherichia whittamii, obtained from diverse environmental sources to assist with improved public health risk assessments.

4.
PLoS One ; 19(1): e0295529, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38236841

RESUMO

Escherichia coli are routine indicators of fecal contamination in water quality assessments. Contrary to livestock and human activities, brushtail possums (Trichosurus vulpecula), common invasive marsupials in Aotearoa/New Zealand, have not been thoroughly studied as a source of fecal contamination in freshwater. To investigate their potential role, Escherichia spp. isolates (n = 420) were recovered from possum gut contents and feces and were compared to those from water, soil, sediment, and periphyton samples, and from birds and other introduced mammals collected within the Makirikiri Reserve, Dannevirke. Isolates were characterized using E. coli-specific real-time PCR targeting the uidA gene, Sanger sequencing of a partial gnd PCR product to generate a gnd sequence type (gST), and for 101 isolates, whole genome sequencing. Escherichia populations from 106 animal and environmental sample enrichments were analyzed using gnd metabarcoding. The alpha diversity of Escherichia gSTs was significantly lower in possums and animals compared with aquatic environmental samples, and some gSTs were shared between sample types, e.g., gST535 (in 85% of samples) and gST258 (71%). Forty percent of isolates gnd-typed and 75% of reads obtained by metabarcoding had gSTs shared between possums, other animals, and the environment. Core-genome single nucleotide polymorphism (SNP) analysis showed limited variation between several animal and environmental isolates (<10 SNPs). Our data show at an unprecedented scale that Escherichia clones are shared between possums, other wildlife, water, and the wider environment. These findings support the potential role of possums as contributors to fecal contamination in Aotearoa/New Zealand freshwater. Our study deepens the current knowledge of Escherichia populations in under-sampled wildlife. It presents a successful application of high-resolution genomic methods for fecal source tracking, thereby broadening the analytical toolbox available to water quality managers. Phylogenetic analysis of isolates and profiling of Escherichia populations provided useful information on the source(s) of fecal contamination and suggest that comprehensive invasive species management strategies may assist in restoring not only ecosystem health but also water health where microbial water quality is compromised.


Assuntos
Animais Selvagens , Trichosurus , Animais , Humanos , Trichosurus/genética , Qualidade da Água , Ecossistema , Filogenia , Escherichia coli/genética , Genômica , Nova Zelândia
5.
Stroke ; 54(9): 2254-2264, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37577801

RESUMO

BACKGROUND: To determine if low-frequency repetitive transcranial magnetic stimulation targeting the primary motor cortex contralateral (M1CL) to the affected corticospinal tract in patients with hemiparetic stroke augments intensive training-related clinical improvement; an extension of the NICHE trial (Navigated Inhibitory rTMS to Contralesional Hemisphere Trial) using an alternative sham coil. METHODS: The present E-FIT trial (Electric Field Navigated 1Hz rTMS for Post-stroke Motor Recovery Trial) included 5 of 12 NICHE trial outpatient US rehabilitation centers. The stimulation protocol remained identical (1 Hz repetitive transcranial magnetic stimulation, M1CL, preceding 60-minute therapy, 18 sessions/6 wks; parallel arm randomized clinical trial). The sham coil appearance mimicked the active coil but without the weak electric field in the NICHE trial sham coil. Outcomes measured 1 week, and 1, 3, and 6 months after the end of treatment included the following: upper extremity Fugl-Meyer (primary, 6 months after end of treatment), Action Research Arm Test, National Institutes of Health Stroke Scale, quality of life (EQ-5D), and safety. RESULTS: Of 60 participants randomized, 58 completed treatment and were included for analysis. Bayesian analysis of combined data from the E-FIT and the NICHE trials indicated that active treatment was not superior to sham at the primary end point (posterior mean odds ratio of 1.94 [96% credible interval of 0.61-4.80]). For the E-FIT intent-to-treat population, upper extremity Fugl-Meyer improvement ≥5 pts occurred in 60% (18/30) active group and 50% (14/28) sham group. Participants enrolled 3 to 6 months following stroke had a 67% (31%-91% CI) response rate in the active group at the 6-month end point versus 50% in the sham group (21.5%-78.5% CI). There were significant improvements from baseline to 6 months for both active and sham groups in upper extremity Fugl-Meyer, Action Research Arm Test, and EQ-5D (P<0.05). Improvement in National Institutes of Health Stroke Scale was observed only in the active group (P=0.004). Ten serious unrelated adverse events occurred (4 active group, 6 sham group, P=0.72). CONCLUSIONS: Intensive motor rehabilitation 3 to 12 months after stroke improved clinical impairment, function, and quality of life; however, 1 Hz-repetitive transcranial magnetic stimulation was not an effective treatment adjuvant in the present sample population with mixed lesion location and extent. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03010462.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Qualidade de Vida , Teorema de Bayes , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Extremidade Superior , Recuperação de Função Fisiológica
6.
Appl Environ Microbiol ; 88(9): e0027722, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35442082

RESUMO

Generic Escherichia coli is commonly used as an indicator of fecal contamination to assess water quality and human health risk. Where measured E. coli exceedances occur, the presence of other pathogenic microorganisms, such as Shiga toxin-producing E. coli (STEC), is assumed, but confirmatory data are lacking. Putative E. coli isolates (n = 709) were isolated from water, sediment, soil, periphyton, and feces samples (n = 189) from five sites representing native forest and agricultural environments. Ten E. coli isolates (1.41%) were stx2 positive, 19 (2.7%) were eae positive, and stx1-positive isolates were absent. At the sample level, stx2-positive E. coli (5 of 189, 2.6%) and eae-positive isolates (16 of 189, 8.5%) were rare. Using real-time PCR, these STEC-associated virulence factors were determined to be more prevalent in sample enrichments (stx1, 23.9%; stx2, 31.4%; eae, 53.7%) and positively correlated with generic E. coli isolate numbers (P < 0.05) determined using culture-based methods. Whole-genome sequencing (WGS) was undertaken on a subset of 238 isolates with assemblies representing seven E. coli phylogroups (A, B1, B2, C, D, E, and F), 22 Escherichia marmotae isolates, and 1 Escherichia ruysiae isolate. Virulence factors, including those from extraintestinal pathogenic E. coli, were extremely diverse in isolates from the different locations and were more common in phylogroup B2. Analysis of the virulome from WGS data permitted the identification of gene repertoires that may be involved in environmental fitness and broadly align with phylogroup. Although recovery of STEC isolates was low, our molecular data indicate that they are likely to be widely present in environmental samples containing diverse E. coli phylogroups. IMPORTANCE This study takes a systematic sampling approach to assess the public health risk of Escherichia coli recovered from freshwater sites within forest and farmland. The New Zealand landscape is dominated by livestock farming, and previous work has demonstrated that "recreational exposure to water" is a risk factor for human infection by Shiga toxin-producing Escherichia coli (STEC). Though STEC isolates were rarely isolated from water samples, STEC-associated virulence factors were identified more commonly from water sample culture enrichments and were associated with increased generic E. coli concentrations. Whole-genome sequencing data from both E. coli and newly described Escherichia spp. demonstrated the presence of virulence factors from E. coli pathotypes, including extraintestinal pathogenic E. coli. This has significance for understanding and interpreting the potential health risk from E. coli where water quality is poor and suggests a role of virulence factors in survival and persistence of E. coli and Escherichia spp.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Shiga Toxigênica , Proteínas de Escherichia coli/genética , Fezes , Humanos , Nova Zelândia , Fatores de Virulência/genética
7.
Appl Environ Microbiol ; 87(11)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33771782

RESUMO

Cattle are asymptomatic carriers of Shiga toxin-producing Escherichiacoli (STEC) strains that can cause serious illness or death in humans. In New Zealand, contact with cattle feces and living near cattle populations are known risk factors for human STEC infection. Contamination of fresh meat with STEC strains also leads to the potential for rejection of consignments by importing countries. We used a combination of PCR/matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) and whole-genome sequencing (WGS) to evaluate the presence and transmission of STEC on farms and in processing plants to better understand the potential pathways for human exposure and thus mitigate risk. Animal and environmental samples (n = 2,580) were collected from six farms and three meat processing plants in New Zealand during multiple sampling sessions in spring of 2015 and 2016. PCR/MALDI-TOF analysis revealed that 6.2% were positive for "Top 7" STEC. Top 7 STEC strains were identified in all sample sources (n = 17) tested. A marked increase in Top 7 STEC prevalence was observed between calf hides on farm (6.3% prevalence) and calf hides at processing plants (25.1% prevalence). Whole-genome sequencing was performed on Top 7 STEC bacterial isolates (n = 40). Analysis of STEC O26 (n = 25 isolates) revealed relatively low genetic diversity on individual farms, consistent with the presence of a resident strain disseminated within the farm environment. Public health efforts should focus on minimizing human contact with fecal material on farms and during handling, transport, and slaughter of calves. Meat processing plants should focus on minimizing cross-contamination between the hides of calves in a cohort during transport, lairage, and slaughter.IMPORTANCE Cattle are asymptomatic carriers of Shiga toxin-producing E. coli (STEC) strains, which can cause serious illness or death in humans. Contact with cattle feces and living near cattle are known risk factors for human STEC infection. This study evaluated STEC carriage in young calves and the farm environment with an in-depth evaluation of six farms and three meat processing plants over 2 years. An advanced molecular detection method and whole-genome sequencing were used to provide a detailed evaluation of the transmission of STEC both within and between farms. The study revealed widespread STEC contamination within the farm environment, but no evidence of recent spread between farms. Contamination of young dairy calf hides increased following transport and holding at meat processing plants. The elimination of STEC in farm environments may be very difficult given the multiple transmission routes; interventions should be targeted at decreasing fecal contamination of calf hides during transport, lairage, and processing.


Assuntos
Doenças dos Bovinos/transmissão , Infecções por Escherichia coli/veterinária , Escherichia coli Shiga Toxigênica/fisiologia , Matadouros , Criação de Animais Domésticos , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Feminino , Nova Zelândia , Reação em Cadeia da Polimerase/veterinária , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Sequenciamento Completo do Genoma/veterinária
8.
Animals (Basel) ; 10(7)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32630255

RESUMO

Denning behavior has long remained the least observed aspect of bear behavior. During 2010-2013, we used webcams, microphones, the internet, and 14,602 h of archived video to document the denning behaviors of two adult wild black bears (Ursus americanus) as they gave birth and cared for four litters through six winters in northeastern Minnesota. Observations included types of dens, labor, pre-parturient genital swelling, birthing positions, post-partum vocalizations, mothers removing amniotic tissues and warming newborn cubs in sub-freezing temperatures, frequency of nursing, cubs establishing nipple order, yearlings suckling, the ingestion of snow and icicles, the ingestion of foot pads, urination and defecation in latrine areas, toilet-licking, eye opening, reciprocal tongue-licking, play, rapid eye movement (REM) sleep and possible dreaming, and reactions to wildlife intruders. The use of this new method for observing natural bear dens allowed the identification of many behaviors undescribed for any species of wild bear in dens. We also discuss the need for future studies and how the depth and duration of black bear hibernation varies with body condition and geographic region.

9.
Int J Syst Evol Microbiol ; 70(6): 3775-3784, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32501787

RESUMO

Six isolates of Campylobacter with similar non-standard colonial morphologies were identified during studies isolating Campylobacter from bird faeces and rivers in New Zealand. Genomic (16S rRNA gene sequencing and whole genome analysis) and phenotypic (MALDI-TOF analysis and conventional biochemical tests) showed that the isolates form a monophyletic clade with genetic relationships to Campylobacter coli/Campylobacter jejuni and Campylobacter peloridis/Campylobacter amoricus. They may be distinguished from other Campylobacter by their MALDI-TOF spectral pattern, their florid α-haemolysis, their ability to grow anaerobically at 37 °C, and on 2 % NaCl nutrient agar, and their lack of hippuricase. This study shows that these isolates represent a novel species within the genus Campylobacter for which the name Campylobacter novaezeelandiae sp. nov. is proposed. The presence of C. novaezeelandiae in water may be a confounder for freshwater microbial risk assessment as they may not be pathogenic for humans. The type strain is B423bT (=NZRM 4741T=ATCC TSD-167T).


Assuntos
Aves/microbiologia , Campylobacter/classificação , Fezes/microbiologia , Filogenia , Rios/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Campylobacter/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Nova Zelândia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Top Stroke Rehabil ; 27(4): 241-250, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31838961

RESUMO

Background: Post-stroke dysphagia is characterized by reduced corticolingual excitability and lingual pressure; however, it remains unknown if transcranial magnetic stimulation (TMS) directly facilitates lingual pressure generation.Objectives: To explore optimal procedures for single pulse TMS using neuronavigation to evoke lingual pressure in intact and disrupted neural networks.Methods: Using co-registered functional magnetic resonance imaging, stimulation sites were determined for five healthy adults (Mage = 67) and four stroke survivors with dysphagia and reduced tongue strength (Mage = 66). Evoked lingual pressures were sampled across 45-65% of maximum stimulator output. Healthy participants repeated TMS with a bite block to isolate lingual pressure from off-target stimulation of mandibular elevators.Results: Only one functionally-guided stimulation site fell within previously reported optimal lateral (8-11cm) and anterior (2-4.25cm) coordinates. Lingual pressure was stable prior to pulse and increased linearly with intensity for both groups (p = .005). Post-stroke active motor thresholds were elevated compared to healthy adults (p = .025). Lingual pressure latency remained stable across intensities (p > .05). Jaw stabilization via bite block reduced the mean magnitude of evoked lingual pressure by approximately 16%.Conclusions: Single pulse TMS directly evokes higher lingual pressure and can define motor thresholds in intact and disordered corticolingual pathways. Stimulation sites using neuronavigation in healthy adults and stroke survivors largely differed from external coordinates in the literature that were predominantly established in young adults. Procedures to investigate motor thresholds for lingual pressure generation are proposed. The therapeutic role of TMS to address post-stroke deficits in lingual pressure and corticolingual excitability warrants continued investigation.


Assuntos
Transtornos de Deglutição/terapia , Potencial Evocado Motor/fisiologia , Imageamento por Ressonância Magnética , Córtex Motor/fisiopatologia , Acidente Vascular Cerebral/terapia , Língua/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Idoso , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Acidente Vascular Cerebral/complicações , Sobreviventes
11.
PLoS One ; 14(11): e0225461, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31751414

RESUMO

New Zealand sea lions (Phocarctos hookeri) are an endemic and endangered species. Pup mortality at Enderby Island (50.5°S, 166.28°E) in the New Zealand sub-Antarctic has been well studied, with subsequent investigations yielding more intricate detail of the causes of mortality, as new diagnostic methods become available. Klebsiella pneumoniae was first reported in 2001-02 at this site, causing a pup mortality epizootic and is now known to be present at several colonies. This bacterium is a common mucosal commensal of humans and animals, however the agent found in pups at necropsy is a hypervirulent strain, readily recognised in microbial culture as being hypermucoviscous. Infection causes septicaemia with a common syndrome of subsequent meningitis and polyarthritis. This investigation uses histopathology and microbiology, with new modalities such as matrix assisted laser desorption/ionisation-time of flight mass spectrometry to show that Klebsiella septicaemia could have historically been, and continues to be, the most important cause of pup mortality, but has been previously underrepresented due to the often cryptic presentation and sometimes peracute course of disease. Hypermucoviscous K. pneumoniae should be considered a serious threat to pup survival in the species, causing on average 60.2% of pup deaths annually at Enderby Island between 2013 and 2018, with likely more continuing mortality following pup dispersal and the cessation of the summer monitoring season. Less common causes of death included starvation (14.8%), trauma/asphyxiation (9.9%) and other infections (7%). This study forms the basis for further evaluation of risk factors for pup mortality in the species, with a view to developing active mitigation.


Assuntos
Infecções por Klebsiella/mortalidade , Klebsiella pneumoniae/patogenicidade , Leões-Marinhos/microbiologia , Sepse/mortalidade , Animais , Espécies em Perigo de Extinção , Feminino , Infecções por Klebsiella/veterinária , Masculino , Mortalidade , Nova Zelândia/epidemiologia , Estudos Retrospectivos , Leões-Marinhos/crescimento & desenvolvimento , Sepse/microbiologia , Sepse/veterinária
12.
Emerg Infect Dis ; 25(12): 2226-2234, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31742539

RESUMO

In 2014, antimicrobial drug-resistant Campylobacter jejuni sequence type 6964 emerged contemporaneously in poultry from 3 supply companies in the North Island of New Zealand and as a major cause of campylobacteriosis in humans in New Zealand. This lineage, not previously identified in New Zealand, was resistant to tetracycline and fluoroquinolones. Genomic analysis revealed divergence into 2 major clades; both clades were associated with human infection, 1 with poultry companies A and B and the other with company C. Accessory genome evolution was associated with a plasmid, phage insertions, and natural transformation. We hypothesize that the tetO gene and a phage were inserted into the chromosome after conjugation, leaving a remnant plasmid that was lost from isolates from company C. The emergence and rapid spread of a resistant clone of C. jejuni in New Zealand, coupled with evolutionary change in the accessory genome, demonstrate the need for ongoing Campylobacter surveillance among poultry and humans.


Assuntos
Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Genoma Bacteriano , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Animais , Antibacterianos/farmacologia , Infecções por Campylobacter/história , Campylobacter jejuni/classificação , Campylobacter jejuni/isolamento & purificação , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/microbiologia , Farmacorresistência Bacteriana , Fluoroquinolonas/farmacologia , Genômica/métodos , História do Século XXI , Humanos , Tipagem de Sequências Multilocus , Nova Zelândia/epidemiologia , Filogenia , Plasmídeos , Polimorfismo de Nucleotídeo Único , Doenças das Aves Domésticas/história , Tetraciclina/farmacologia , Sequenciamento Completo do Genoma
13.
Microbiol Resour Announc ; 8(47)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31753948

RESUMO

Draft genomes of five Campylobacter isolates recovered from New Zealand brushtail possums are described. Genome sizes ranged from 1.591 Mbp to 1.594 Mbp, with G+C contents of 29.9% to 29.95%. Comparison to Australian Campylobacter 16S rRNA gene sequences suggests that the species may be common to possums.

14.
Emerg Infect Dis ; 25(3): 489-500, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30789138

RESUMO

Shiga toxin-producing Escherichia coli serogroup O26 is an important public health pathogen. Phylogenetic bacterial lineages in a country can be associated with the level and timing of international imports of live cattle, the main reservoir. We sequenced the genomes of 152 E. coli O26 isolates from New Zealand and compared them with 252 E. coli O26 genomes from 14 other countries. Gene variation among isolates from humans, animals, and food was strongly associated with country of origin and stx toxin profile but not isolation source. Time of origin estimates indicate serogroup O26 sequence type 21 was introduced at least 3 times into New Zealand from the 1920s to the 1980s, whereas nonvirulent O26 sequence type 29 strains were introduced during the early 2000s. New Zealand's remarkably fewer introductions of Shiga toxin-producing Escherichia coli O26 compared with other countries (such as Japan) might be related to patterns of trade in live cattle.


Assuntos
Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Variação Genética , Genoma Bacteriano , Genômica , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Biologia Computacional/métodos , Bases de Dados Genéticas , Farmacorresistência Bacteriana , Infecções por Escherichia coli/transmissão , Evolução Molecular , Genômica/métodos , Saúde Global , Humanos , Anotação de Sequência Molecular , Nova Zelândia/epidemiologia , Filogenia , Sorogrupo , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Escherichia coli Shiga Toxigênica/isolamento & purificação
15.
PLoS One ; 14(2): e0212363, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30753243

RESUMO

Mycobacterium pinnipedii causes tuberculosis in a number of pinniped species, and transmission to cattle and humans has been reported. The aims of this study were to: characterize the pathology and prevalence of tuberculosis in New Zealand marine mammals; use molecular diagnostic methods to confirm and type the causal agent; and to explore relationships between type and host characteristics. Tuberculosis was diagnosed in 30 pinnipeds and one cetacean. Most affected pinnipeds had involvement of the pulmonary system, supporting inhalation as the most common route of infection, although ingestion was a possible route in the cetacean. PCR for the RD2 gene confirmed M. pinnipedii as the causal agent in 23/31 (74%) cases (22 using DNA from cultured organisms, and one using DNA from formalin-fixed paraffin-embedded (FFPE) tissue), including the first published report in a cetacean. RD2 PCR results were compared for 22 cases where both cultured organisms and FFPE tissues were available, with successful identification of M. pinnipedii in 7/22 (31.8%). In cases with moderate to large numbers of acid-fast bacilli, RD2 PCR on FFPE tissue provided a rapid, inexpensive method for confirming M. pinnipedii infection without the need for culture. VNTR typing distinguished New Zealand M. pinnipedii isolates from M. pinnipedii isolated from Australian pinnipeds and from common types of M. bovis in New Zealand. Most (16/18) M. pinnipedii isolates from New Zealand sea lions were one of two common VNTR types whereas the cetacean isolate was a type detected previously in New Zealand cattle.


Assuntos
Cetáceos/microbiologia , DNA Bacteriano/genética , Infecções por Mycobacterium/patologia , Infecções por Mycobacterium/veterinária , Mycobacterium/isolamento & purificação , Animais , Feminino , Masculino , Epidemiologia Molecular , Mycobacterium/classificação , Mycobacterium/genética , Infecções por Mycobacterium/epidemiologia , Infecções por Mycobacterium/microbiologia , Nova Zelândia/epidemiologia
16.
Stroke ; 49(9): 2138-2146, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30354990

RESUMO

Background and Purpose- We aimed to determine whether low-frequency electric field navigated repetitive transcranial magnetic stimulation to noninjured motor cortex versus sham repetitive transcranial magnetic stimulation avoiding motor cortex could improve arm motor function in hemiplegic stroke patients when combined with motor training. Methods- Twelve outpatient US rehabilitation centers enrolled participants between May 2014 and December 2015. We delivered 1 Hz active or sham repetitive transcranial magnetic stimulation to noninjured motor cortex before each of eighteen 60-minute therapy sessions over a 6-week period, with outcomes measured at 1 week and 1, 3, and 6 months after end of treatment. The primary end point was the percentage of participants improving ≥5 points on upper extremity Fugl-Meyer score 6 months after end of treatment. Secondary analyses assessed changes on the upper extremity Fugl-Meyer and Action Research Arm Test and Wolf Motor Function Test and safety. Results- Of 199 participants, 167 completed treatment and follow-up because of early discontinuation of data collection. Upper extremity Fugl-Meyer gains were significant for experimental ( P<0.001) and sham groups ( P<0.001). Sixty-seven percent of the experimental group (95% CI, 58%-75%) and 65% of sham group (95% CI, 52%-76%) improved ≥5 points on 6-month upper extremity Fugl-Meyer ( P=0.76). There was also no difference between experimental and sham groups in the Action Research Arm Test ( P=0.80) or the Wolf Motor Function Test ( P=0.55). A total of 26 serious adverse events occurred in 18 participants, with none related to the study or device, and with no difference between groups. Conclusions- Among patients 3 to 12 months poststroke, goal-oriented motor rehabilitation improved motor function 6 months after end of treatment. There was no difference between the active and sham repetitive transcranial magnetic stimulation trial arms. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02089464.


Assuntos
Córtex Motor , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento , Extremidade Superior/fisiopatologia
17.
Bioinformatics ; 34(17): 3025-3027, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29608746

RESUMO

Motivation: Large-scale whole-genome sequencing dataset-based studies are becoming increasingly common in pathogen surveillance and outbreak investigations. A highly discriminative and time-efficient bioinformatics tool is needed to transform large amounts of sequencing data into usable biological information. To replace the intuitive, yet inefficient, way of gene-by-gene allele calling algorithm, a new algorithm using genome-by-genome approach was developed. Results: Tests showed that the program equipped with the new algorithm achieved significant improvements in allele calling efficiency compared to a conventional gene-by-gene approach. The new program, Fast-GeP, rendered a fast and easy way to infer high-resolution genealogical relationships between bacterial isolates using whole-genome sequencing data. Availability and implementation: FAST-GeP is freely available from: https://github.com/jizhang-nz/fast-GeP. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Bactérias/genética , Genoma , Algoritmos , Linhagem , Software , Sequenciamento Completo do Genoma
18.
Sci Rep ; 8(1): 2393, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29403020

RESUMO

Campylobacter hyointestinalis is a member of an emerging group of zoonotic Campylobacter spp. that are increasingly identified in both gastric and non-gastric disease in humans. Here, we discovered C. hyointestinalis in three separate classes of New Zealand ruminant livestock; cattle, sheep and deer. To investigate the relevance of these findings we performed a systematic literature review on global C. hyointestinalis epidemiology and used comparative genomics to better understand and classify members of the species. We found that C. hyointestinalis subspecies hyointestinalis has an open pangenome, with accessory gene contents involved in many essential processes such as metabolism, virulence and defence. We observed that horizontal gene transfer is likely to have played an overwhelming role in species diversification, favouring a public-goods-like mechanism of gene 'acquisition and resampling' over a tree-of-life-like vertical inheritance model of evolution. As a result, simplistic gene-based inferences of taxonomy by similarity are likely to be misleading. Such genomic plasticity will also mean that local evolutionary histories likely influence key species characteristics, such as host-association and virulence. This may help explain geographical differences in reported C. hyointestinalis epidemiology and limits what characteristics may be generalised, requiring further genomic studies of C. hyointestinalis in areas where it causes disease.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter hyointestinalis/classificação , Campylobacter hyointestinalis/genética , Variação Genética , Filogenia , Zoonoses/epidemiologia , Zoonoses/microbiologia , Animais , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter hyointestinalis/isolamento & purificação , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Cervos , Evolução Molecular , Transferência Genética Horizontal , Genoma Bacteriano , Genômica , Nova Zelândia/epidemiologia , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia
20.
Neurorehabil Neural Repair ; 31(4): 354-363, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27932695

RESUMO

BACKGROUND: Following biceps transfer to enable elbow extension in individuals with tetraplegia, motor re-education may be facilitated by greater corticomotor excitability. Arm posture modulates corticomotor excitability of the nonimpaired biceps. If arm posture also modulates excitability of the transferred biceps, posture may aid in motor re-education. OBJECTIVE: Our objective was to determine whether multi-joint arm posture affects corticomotor excitability of the transferred biceps similar to the nonimpaired biceps. We also aimed to determine whether corticomotor excitability of the transferred biceps is related to elbow extension strength and muscle length. METHODS: Corticomotor excitability was assessed in 7 arms of individuals with tetraplegia and biceps transfer using transcranial magnetic stimulation and compared to biceps excitability of nonimpaired individuals. Single-pulse transcranial magnetic stimulation was delivered to the motor cortex with the arm in functional postures at rest. Motor-evoked potential amplitude was recorded via surface electromyography. Elbow moment was recorded during maximum isometric extension trials, and muscle length was estimated using a biomechanical model. RESULTS: Arm posture modulated corticomotor excitability of the transferred biceps differently than the nonimpaired biceps. Elbow extension strength was positively related and muscle length was unrelated, respectively, to motor-evoked potential amplitude across the arms with biceps transfer. CONCLUSIONS: Corticomotor excitability of the transferred biceps is modulated by arm posture and may contribute to strength outcomes after tendon transfer. Future work should determine whether modulating corticomotor excitability via posture promotes motor re-education during the rehabilitative period following surgery.


Assuntos
Braço/fisiopatologia , Córtex Motor/fisiopatologia , Músculo Esquelético/fisiopatologia , Postura/fisiologia , Quadriplegia/fisiopatologia , Adulto , Braço/patologia , Fenômenos Biomecânicos , Eletromiografia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Contração Isométrica/fisiologia , Masculino , Modelos Biológicos , Força Muscular/fisiologia , Músculo Esquelético/patologia , Tamanho do Órgão , Quadriplegia/patologia , Estimulação Magnética Transcraniana , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA