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1.
J Chem Phys ; 153(8): 084301, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872887

RESUMO

Rydberg states of molecules are intrinsically challenging to study due to the presence of fast non-radiative decay pathways, such as predissociation. However, selectively exciting Rydberg states with values of the orbital angular momentum (ℓ) ℓ ≳ 3 is a productive strategy to minimize this rapid decay and to populate molecular Rydberg states with lifetimes that approach those of atoms. In this proof-of-principle demonstration, we transfer population to an nf Rydberg state of the calcium atom by stimulated Raman adiabatic passage, in which an optical and a millimeter-wave field couple the initial and final states via an intermediate nd Rydberg state. Numerical simulations reproduce the observed time and frequency dependences of the population transfer and suggest the utility of this scheme to populate high-ℓ Rydberg states of molecules.

2.
Microb Ecol ; 80(3): 501-506, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32440699

RESUMO

Bacteria belonging to the genus Vibrio are major carbon cycle drivers in marine and estuarine environments. As is the case for most carbon cycle participants, the vibrios metabolize degradable compounds such as sugars and amino acids; they can also degrade some more recalcitrant compounds including hydrocarbons and lignins. Several vibrios are symbionts and even fewer are pathogenic for animals, including humans and marine animals and plants. This paper reviews Vibrio ecology, metabolism, and survival, and it also discusses select vibrios-V. alginolyticus, V. cholerae, V. coralliilyticus, V. cortegadensis, V. fischeri, V. harveyi, V. harveyi var. carahariae, V. ordalii, V. parahaemolyticus, and V. vulnificus.


Assuntos
Carbono/metabolismo , Vibrio/fisiologia , Ciclo do Carbono , Características de História de Vida , Simbiose , Vibrio/metabolismo
3.
Sci Total Environ ; 732: 139125, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32438143

RESUMO

Aquatic contamination, oil spills in particular, could lead to the accumulation of antibiotic resistance by promoting selection for and/or transfer of resistance genes. However, there have been few studies on antibiotic resistance in marine mammals in relation to environmental disturbances, specifically oil contaminations. Here we initiated a study on antibiotic resistance bacteria in bottlenose dolphins Tursiops truncatus in relation to oil contamination following the 2010 BP Oil Spill in the northern Gulf of Mexico. Bacterial communities and antibiotic resistance prevalence one year after the 2010 BP Oil Spill were compared between Barataria Bay (BB) and Sarasota Bay (SB) by applying the rarefaction curve method, and (generalized) linear mixed models. The results showed that the most common bacteria included Vibrio, Shewanella, Bacillus and Pseudomonas. The prevalence of antibiotic resistance was high in the bacterial isolates at both bays. Though bacterial diversity did not differ significantly among water or dolphin samples, and antibiotic resistance did not differ significantly among water samples between the two bays, antibiotic resistance and multi-drug resistance in dolphin samples was significantly higher in the BB than in the SB, mainly attributed to the resistance to E, CF, FEP and SXT. We also found sulfamethoxazole-trimethoprim-resistant Stenotrophomonas maltophilia the first time in the natural aquatic environment. The higher antibiotic resistance in the dolphins in BB is likely attributed to 2010 BP Oil Spill as we expected SB, a more urbanized bay area, would have had higher antibiotic resistance based on the previous studies. The antibiotic resistance data gathered in this research will fill in the important data gaps and contributes to the broader spatial-scale emerging studies on antibiotic resistance in aquatic environments.


Assuntos
Golfinho Nariz-de-Garrafa , Animais , Bactérias , Farmacorresistência Bacteriana , Golfo do México , Poluição por Petróleo
4.
Int J Oral Maxillofac Surg ; 49(4): 442-445, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31561844

RESUMO

At Queens Medical Centre, Nottingham, alveolar bone grafts (ABG) for patients with cleft lip and palate (CLP) were performed by two surgeons following the same surgical protocol, but with different postoperative iliac crest donor site analgesia: surgeon A used a donor site bolus of levobupivacaine, whilst surgeon B used a donor site epidural catheter (EC) infusing levobupivacaine. A healthcare evaluation was conducted in two phases to establish the effectiveness of analgesia for CLP patients undergoing ABGs. Data were collected prospectively in 2016 and 2018. Cleft patients postoperative to ABG were included. Outcome measures were pain scores at 2, 4, 6, 12, and 24 hours, time to mobilization, and time to food intake. Mean pain scores at the first evaluation were <1 out of 10 for all time points, except 24 hours (score 2.0 for bolus, 1.8 for EC). There was no statistically significant difference between the groups for any of the outcomes measured. As EC conferred no advantage, surgeon B changed to bolus administration and a second evaluation was performed. The mean pain score for the second evaluation was 1.7 and higher pain scores were more common with lower doses of levobupivacaine. The data suggest that bolus injection can produce safe, effective pain control provided an adequate dose is given.


Assuntos
Analgesia , Fissura Palatina , Transplante Ósseo , Humanos , Ílio , Dor , Dor Pós-Operatória
5.
Science ; 366(6469): 1111-1115, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31780555

RESUMO

Femtochemistry techniques have been instrumental in accessing the short time scales necessary to probe transient intermediates in chemical reactions. In this study, we took the contrasting approach of prolonging the lifetime of an intermediate by preparing reactant molecules in their lowest rovibronic quantum state at ultralow temperatures, thereby markedly reducing the number of exit channels accessible upon their mutual collision. Using ionization spectroscopy and velocity-map imaging of a trapped gas of potassium-rubidium (KRb) molecules at a temperature of 500 nanokelvin, we directly observed reactants, intermediates, and products of the reaction 40K87Rb + 40K87Rb → K2Rb2* → K2 + Rb2 Beyond observation of a long-lived, energy-rich intermediate complex, this technique opens the door to further studies of quantum-state-resolved reaction dynamics in the ultracold regime.

7.
Microb Ecol ; 75(2): 303-309, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29080910

RESUMO

The dermis of cetaceans is in constant contact with microbial species. Although the skin of the bottlenose dolphin provides adequate defense against most disease-causing microbes, it also provides an environment for microbial community development. Microbial community uniqueness and richness associated with bottlenose dolphin skin is a function of varying habitats and changing environmental conditions. The current study uses ribosomal DNA as a marker to identify bacteria found on the skin of coastal and offshore bottlenose dolphins off of Southern California. The unique microbial communities recovered from these dolphins suggest a greater microbial diversity on the skin of offshore ecotype bottlenose dolphins, while microbial populations associated with the coastal ecotype include species that are more closely related to each other and that suggest exposure to communities that are likely to be associated with terrestrial runoff.


Assuntos
Bactérias/isolamento & purificação , Golfinho Nariz-de-Garrafa/microbiologia , Pele/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Biodiversidade , California , DNA Bacteriano/genética , DNA Ribossômico/genética , Ecossistema , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia
8.
Br J Oral Maxillofac Surg ; 55(4): 404-406, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27823849

RESUMO

Changes to guidance about the two-week wait referrals for suspected cancer of the head and neck have created a new recommendation for a general medical practitioner to refer any patients to a dentist under certain criteria. The potential effect of this was assessed based on 91 referrals to an oral and maxillofacial unit. A total of 33 met the criteria for initial referral to a dentist; of these, one was later diagnosed with cancer. We outline the potential deleterious effects the new guidance might have on the rapid diagnosis of oral lesions.


Assuntos
Diagnóstico Tardio , Neoplasias Bucais/diagnóstico , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta , Inglaterra , Humanos , Auditoria Médica , Estudos Retrospectivos
9.
Microb Ecol ; 73(1): 91-100, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27815589

RESUMO

The environmental impact of major oil spills on marine microorganisms has yet to be thoroughly investigated using molecular biology techniques. The Deepwater Horizon (DWH) drilling rig explosion of 2010 affected an approximately 176,000 km2 surface area of the Gulf of Mexico (GOM) when an estimated 210 million gallons of oil from the Macondo Prospect spilled into the environment. Pelagic Sargassum, a complex of two surface drifting species (Sargassum natans and Sargassum fluitans) of marine brown macroalgae and a critically important habitat in the GOM ecosystem, was suffused by Macondo Prospect 252 oil released during the DWH event. Using 16S rRNA PCR and Roche 454 pyrosequencing, the effect of the oil on the bacterial population associated with pelagic Sargassum and contiguous waters was examined by comparing sequence data generated from samples collected from oiled and non-oiled locations in the northern GOM. Sequence data showed similar microbial composition in Sargassum regardless of exposure to oil primarily dominated by five phyla; Proteobacteria, Bacteroidetes, Actinobacteria, Verrucomicrobia, and unclassified bacteria. The microbial composition in water samples was significantly less diverse than for Sargassum and consisted primarily of Proteobacteria, Firmicutes, and Bacteroidetes. Due to the evenly distributed abundance of microbial species on oiled and non-oiled pelagic Sargassum, study findings indicate that DWH spilled oil had minimal effect on the composition and diversity of the microbial community associated with Sargassum and contiguous waters. However, higher abundances of Sulfitobacter and one species of Psychrobacter were found in oiled water samples when compared to non-oiled water samples indicating some effect of DHW oil in the microbial composition of seawater. Though there are a number of marine studies using molecular biology approaches, this is the first molecular examination of the impact of the DWH oil spill on bacterial communities associated with pelagic Sargassum and contiguous waters from the GOM.


Assuntos
Actinobacteria/classificação , Bacteroidetes/classificação , Monitoramento Ambiental/métodos , Firmicutes/classificação , Poluição por Petróleo , Proteobactérias/classificação , Sargassum/microbiologia , Verrucomicrobia/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , DNA Bacteriano/genética , Meio Ambiente , Firmicutes/genética , Firmicutes/isolamento & purificação , Golfo do México , Microbiota/genética , Indústria de Petróleo e Gás , Petróleo/toxicidade , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/genética , Sargassum/crescimento & desenvolvimento , Água do Mar/química , Água do Mar/microbiologia , Verrucomicrobia/genética , Verrucomicrobia/isolamento & purificação
11.
Science ; 352(6291): 1341-4, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27284198

RESUMO

Idiopathic scoliosis (IS) affects 3% of children worldwide, yet the mechanisms underlying this spinal deformity remain unknown. Here we show that ptk7 mutant zebrafish, a faithful developmental model of IS, exhibit defects in ependymal cell cilia development and cerebrospinal fluid (CSF) flow. Transgenic reintroduction of Ptk7 in motile ciliated lineages prevents scoliosis in ptk7 mutants, and mutation of multiple independent cilia motility genes yields IS phenotypes. We define a finite developmental window for motile cilia in zebrafish spine morphogenesis. Notably, restoration of cilia motility after the onset of scoliosis blocks spinal curve progression. Together, our results indicate a critical role for cilia-driven CSF flow in spine development, implicate irregularities in CSF flow as an underlying biological cause of IS, and suggest that noninvasive therapeutic intervention may prevent severe scoliosis.


Assuntos
Líquido Cefalorraquidiano/fisiologia , Modelos Animais de Doenças , Escoliose/líquido cefalorraquidiano , Escoliose/fisiopatologia , Coluna Vertebral/anormalidades , Peixe-Zebra/anormalidades , Animais , Animais Geneticamente Modificados , Cílios/fisiologia , Epêndima/anormalidades , Hidrocefalia/genética , Hidrocefalia/patologia , Mutação , Receptores Proteína Tirosina Quinases/genética , Escoliose/genética , Peixe-Zebra/líquido cefalorraquidiano , Peixe-Zebra/genética , Proteínas de Peixe-Zebra
12.
Chaos ; 25(10): 103116, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26520082

RESUMO

Natural systems dominated by sediment transport are notoriously difficult to forecast. This is particularly true along the ocean coastline, a region that draws considerable human attention as economic investment and infrastructure are threatened by both persistent, long-term and acute, event driven processes (i.e., sea level rise and storm damage, respectively). Forecasting the coastline's evolution over intermediate time (daily) and space (tens of meters) scales is hindered by the complexity of sediment transport and hydrodynamics, and limited access to the detailed local forcing that drives fast scale processes. Modern remote sensing systems provide an efficient, economical means to collect data within these regions. A solar-powered digital camera installation is used to capture the coast's evolution, and machine learning algorithms are implemented to extract the shoreline and estimate the daily mean intertidal coastal profile. Methods in nonlinear time series forecasting and genetic programming applied to these data corroborate that coastal morphology at these scales is predominately driven by nonlinear internal dynamics, which partially mask external forcing signatures. Results indicate that these forecasting techniques achieve nontrivial predictive skill for spatiotemporal forecast of the upper coastline profile (as much as 43% of variance in data explained for one day predictions). This analysis provides evidence that societally relevant coastline forecasts can be achieved without knowing the forcing environment or the underlying dynamical equations that govern coastline evolution.

13.
J Clin Microbiol ; 53(1): 9-14, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25339398

RESUMO

An occurrence of Vibrio cholerae non-O1/O139 gastroenteritis in the U.S. Gulf Coast is reported here. Genomic analysis revealed that the isolate lacked known virulence factors associated with the clinical outcome of a V. cholerae infection but did contain putative genomic islands and other accessory virulence factors. Many of these factors are widespread among environmental strains of V. cholerae, suggesting that there might be additional virulence factors in non-O1/O139 V. cholerae yet to be determined. Phylogenetic analysis revealed that the isolate belonged to a phyletic lineage of environmental V. cholerae isolates associated with sporadic cases of gastroenteritis in the Western Hemisphere, suggesting a need to monitor non-O1/O139 V. cholerae in the interest of public health.


Assuntos
Gastroenterite/microbiologia , Vibrioses/microbiologia , Vibrio cholerae não O1/classificação , Adulto , Mapeamento Cromossômico , Análise por Conglomerados , Biologia Computacional , Gastroenterite/diagnóstico , Ordem dos Genes , Genes Bacterianos , Genoma Bacteriano , Humanos , Masculino , Tipagem Molecular , Filogenia , Estados Unidos , Vibrioses/diagnóstico , Vibrio cholerae não O1/genética , Vibrio cholerae não O1/isolamento & purificação , Fatores de Virulência/genética
14.
Lett Appl Microbiol ; 58(6): 624-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24698333

RESUMO

UNLABELLED: Vibrio parahaemolyticus is a pathogenic marine bacterium that causes food-borne gastroenteritis and, less commonly, wound infections. As is the case for many pathogens, all V. parahaemolyticus strains possess at least one erythrocyte-lysing haemolysin. In addition, many V. parahaemolyticus also possess the enzyme urease. We tested 206 environmental V. parahaemolyticus isolates from Mississippi coastal waters for urease and haemolytic activity using urea agar with added salt and Wagatsuma agar, respectively. The relative abundance of haemolysin-producing V. parahaemolyticus was consistently high throughout the sampling period. In contrast, the number of urease-positive organisms increased from 36% in 2006 to 80% in 2007 and 97% in 2009. We then tested the ability of four strains representing each of the three sample years along with seven other bacterial strains for their ability to grow in seawater urea and raise the pH of this seawater broth. Finally, one of the 4 strains was tested for its ability to form an alkaline microhabitat immediately above its biofilm. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study illustrate that V. parahaemolyticus has the ability to create alkaline microhabitats that could enhance virulence, including virulence from haemolysins. This finding could have both clinical and ecological impact as to how V. parahaemolyticus can modify its habitat.


Assuntos
Proteínas de Bactérias/biossíntese , Urease/biossíntese , Vibrio parahaemolyticus/enzimologia , Ecossistema , Hemólise , Humanos , Concentração de Íons de Hidrogênio , Mississippi , Água do Mar/química , Água do Mar/microbiologia , Microbiologia da Água
15.
Microb Ecol ; 67(3): 489-500, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24477922

RESUMO

Satellite-based remote sensing of marine microorganisms has become a useful tool in predicting human health risks associated with these microscopic targets. Early applications were focused on harmful algal blooms, but more recently methods have been developed to interrogate the ocean for bacteria. As satellite-based sensors have become more sophisticated and our ability to interpret information derived from these sensors has advanced, we have progressed from merely making fascinating pictures from space to developing process models with predictive capability. Our understanding of the role of marine microorganisms in primary production and global elemental cycles has been vastly improved as has our ability to use the combination of remote sensing data and models to provide early warning systems for disease outbreaks. This manuscript will discuss current approaches to monitoring cyanobacteria and vibrios, their activity and response to environmental drivers, and will also suggest future directions.


Assuntos
Organismos Aquáticos/fisiologia , Cianobactérias/fisiologia , Meio Ambiente , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto , Vibrio/fisiologia , Oceanos e Mares , Astronave
16.
J Microbiol Methods ; 94(2): 98-102, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23660708

RESUMO

A new selective and differential medium, Vibrio vulnificus X-Gal (VVX), was developed for direct enumeration of V. vulnificus (Vv) from oyster samples. This agar utilizes cellobiose and lactose as carbon sources, and the antibiotics colistin and polymyxin B as selective agents. Hydrolysis of 5-bromo-4-chloro-3-indolyl- beta-d-galactopyranoside (x-gal), used in the agar as a lactose analog, produces an insoluble blue dye that makes lactose positive colonies easily distinguishable from any non-lactose fermenting bacteria. Various bacterial species were spot plated onto thiosulfate-citrate-bile salts-sucrose agar (TCBS), and CHROMagar Vibrio, two vibrio-specific selective agars, non-selective agar, and VVX to compare selectivity of VVX to other widely used media. A V. vulnificus pure culture was serially diluted on VVX and non-selective agar to determine the VVX percent recovery. Water and oyster samples were spread plated on VVX agar and allowed to incubate for 16-18 h at 33 °C. Blue and white colonies from VVX agar were picked and screened by end point PCR for the Vv hemolysin vvhA. VVX agar showed a significant improvement over TCBS and CHROMagar at preventing non-target growth. There was an 87.5% recovery compared to non-selective plating and a 98% positivity rate of blue colonies picked from oyster tissue plating. The findings suggest that this new agar is a fast, distinctive, and accurate method for enumeration of V. vulnificus from the environment.


Assuntos
Contagem de Colônia Microbiana/métodos , Ostreidae/microbiologia , Frutos do Mar/microbiologia , Vibrio vulnificus/crescimento & desenvolvimento , Vibrio vulnificus/isolamento & purificação , Animais , Contagem de Colônia Microbiana/instrumentação , Meios de Cultura/metabolismo , Contaminação de Alimentos/análise , Vibrio vulnificus/metabolismo
17.
Microb Ecol ; 65(3): 578-83, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23494573

RESUMO

In response to a major influx of freshwater to the Mississippi Sound following the opening of the Bonnet Carre Spillway, water samples were collected from three sites along the Mississippi shoreline to assess the impact of altered salinity on three pathogenic Vibrio species. Salinity readings across the affected area during the 2011 sample period ranged from 1.4 to 12.9 ppt (mean = 7.0) and for the 2012 sample period from 14.1 to 23.6 ppt (mean = 19.8). Analyses of the data collected in 2011 showed a reduction in densities of Vibrio parahaemolyticus and Vibrio vulnificus with a concurrent increase of Vibrio cholerae numbers, with V. cholerae becoming the only Vibrio detected once salinity readings dropped to 6 ppt. Follow-up samples taken in 2012 after recovery of the salinity in the sound showed that the relative densities of the three pathogenic vibrios had reverted back to normal levels. This study shows that although the spillway was open but a few weeks and the effects were therefore time limited, the Mississippi River water had a profound, if temporary, effect on Vibrio ecology in the Mississippi Sound.


Assuntos
Rios/microbiologia , Vibrio cholerae/crescimento & desenvolvimento , Vibrio vulnificus/crescimento & desenvolvimento , Ecossistema , Rios/química , Salinidade , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo , Vibrio cholerae/isolamento & purificação , Vibrio cholerae/metabolismo , Vibrio parahaemolyticus/crescimento & desenvolvimento , Vibrio parahaemolyticus/isolamento & purificação , Vibrio parahaemolyticus/metabolismo , Vibrio vulnificus/isolamento & purificação , Vibrio vulnificus/metabolismo
19.
Appl Environ Microbiol ; 78(20): 7249-57, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22865080

RESUMO

Vibrio parahaemolyticus and Vibrio vulnificus, which are native to estuaries globally, are agents of seafood-borne or wound infections, both potentially fatal. Like all vibrios autochthonous to coastal regions, their abundance varies with changes in environmental parameters. Sea surface temperature (SST), sea surface height (SSH), and chlorophyll have been shown to be predictors of zooplankton and thus factors linked to vibrio populations. The contribution of salinity, conductivity, turbidity, and dissolved organic carbon to the incidence and distribution of Vibrio spp. has also been reported. Here, a multicoastal, 21-month study was conducted to determine relationships between environmental parameters and V. parahaemolyticus and V. vulnificus populations in water, oysters, and sediment in three coastal areas of the United States. Because ecologically unique sites were included in the study, it was possible to analyze individual parameters over wide ranges. Molecular methods were used to detect genes for thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) as indicators of V. parahaemolyticus and the hemolysin gene vvhA for V. vulnificus. SST and suspended particulate matter were found to be strong predictors of total and potentially pathogenic V. parahaemolyticus and V. vulnificus. Other predictors included chlorophyll a, salinity, and dissolved organic carbon. For the ecologically unique sites included in the study, SST was confirmed as an effective predictor of annual variation in vibrio abundance, with other parameters explaining a portion of the variation not attributable to SST.


Assuntos
Sedimentos Geológicos/microbiologia , Ostreidae/microbiologia , Água do Mar/microbiologia , Vibrio parahaemolyticus/crescimento & desenvolvimento , Vibrio vulnificus/crescimento & desenvolvimento , Animais , Carga Bacteriana , Proteínas de Bactérias/genética , Carbono/análise , Clorofila/análise , Clorofila A , Proteínas Hemolisinas/genética , Dinâmica Populacional , Salinidade , Água do Mar/química , Estados Unidos , Fatores de Virulência/genética
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