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1.
Can Assoc Radiol J ; 74(1): 211-216, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36065604

RESUMEN

This review explores the priorities and future opportunities of interventional radiology in Canada.


Asunto(s)
Radiología Intervencionista , Sociedades Médicas , Humanos , Predicción , Canadá , Derivación y Consulta
2.
Nat Methods ; 15(3): 201-206, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29334379

RESUMEN

Sequencing the RNA in a biological sample can unlock a wealth of information, including the identity of bacteria and viruses, the nuances of alternative splicing or the transcriptional state of organisms. However, current methods have limitations due to short read lengths and reverse transcription or amplification biases. Here we demonstrate nanopore direct RNA-seq, a highly parallel, real-time, single-molecule method that circumvents reverse transcription or amplification steps. This method yields full-length, strand-specific RNA sequences and enables the direct detection of nucleotide analogs in RNA.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Nanoporos , ARN de Hongos/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Análisis de Secuencia de ARN/métodos
4.
Plant Biotechnol J ; 17(12): 2246-2258, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31022325

RESUMEN

Years of selection for desirable fruit quality traits in dessert watermelon (Citrullus lanatus) has resulted in a narrow genetic base in modern cultivars. Development of novel genomic and genetic resources offers great potential to expand genetic diversity and improve important traits in watermelon. Here, we report a high-quality genome sequence of watermelon cultivar 'Charleston Gray', a principal American dessert watermelon, to complement the existing reference genome from '97103', an East Asian cultivar. Comparative analyses between genomes of 'Charleston Gray' and '97103' revealed genomic variants that may underlie phenotypic differences between the two cultivars. We then genotyped 1365 watermelon plant introduction (PI) lines maintained at the U.S. National Plant Germplasm System using genotyping-by-sequencing (GBS). These PI lines were collected throughout the world and belong to three Citrullus species, C. lanatus, C. mucosospermus and C. amarus. Approximately 25 000 high-quality single nucleotide polymorphisms (SNPs) were derived from the GBS data using the 'Charleston Gray' genome as the reference. Population genomic analyses using these SNPs discovered a close relationship between C. lanatus and C. mucosospermus and identified four major groups in these two species correlated to their geographic locations. Citrullus amarus was found to have a distinct genetic makeup compared to C. lanatus and C. mucosospermus. The SNPs also enabled identification of genomic regions associated with important fruit quality and disease resistance traits through genome-wide association studies. The high-quality 'Charleston Gray' genome and the genotyping data of this large collection of watermelon accessions provide valuable resources for facilitating watermelon research, breeding and improvement.


Asunto(s)
Citrullus/genética , Genoma de Planta , Mapeo Cromosómico , Resistencia a la Enfermedad , Frutas , Estudios de Asociación Genética , Genómica , Polimorfismo de Nucleótido Simple
5.
Appl Environ Microbiol ; 85(7)2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30737348

RESUMEN

In the human gut, Clostridium scindens ATCC 35704 is a predominant bacterium and one of the major bile acid 7α-dehydroxylating anaerobes. While this organism is well-studied relative to bile acid metabolism, little is known about the basic nutrition and physiology of C. scindens ATCC 35704. To determine the amino acid and vitamin requirements of C. scindens, the leave-one-out (one amino acid group or vitamin) technique was used to eliminate the nonessential amino acids and vitamins. With this approach, the amino acid tryptophan and three vitamins (riboflavin, pantothenate, and pyridoxal) were found to be required for the growth of C. scindens In the newly developed defined medium, C. scindens fermented glucose mainly to ethanol, acetate, formate, and H2. The genome of C. scindens ATCC 35704 was completed through PacBio sequencing. Pathway analysis of the genome sequence coupled with transcriptome sequencing (RNA-Seq) under defined culture conditions revealed consistency with the growth requirements and end products of glucose metabolism. Induction with bile acids revealed complex and differential responses to cholic acid and deoxycholic acid, including the expression of potentially novel bile acid-inducible genes involved in cholic acid metabolism. Responses to toxic deoxycholic acid included expression of genes predicted to be involved in DNA repair, oxidative stress, cell wall maintenance/metabolism, chaperone synthesis, and downregulation of one-third of the genome. These analyses provide valuable insight into the overall biology of C. scindens which may be important in treatment of disease associated with increased colonic secondary bile acids.IMPORTANCEC. scindens is one of a few identified gut bacterial species capable of converting host cholic acid into disease-associated secondary bile acids such as deoxycholic acid. The current work represents an important advance in understanding the nutritional requirements and response to bile acids of the medically important human gut bacterium, C. scindens ATCC 35704. A defined medium has been developed which will further the understanding of bile acid metabolism in the context of growth substrates, cofactors, and other metabolites in the vertebrate gut. Analysis of the complete genome supports the nutritional requirements reported here. Genome-wide transcriptomic analysis of gene expression in the presence of cholic acid and deoxycholic acid provides a unique insight into the complex response of C. scindens ATCC 35704 to primary and secondary bile acids. Also revealed are genes with the potential to function in bile acid transport and metabolism.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Clostridiales/genética , Clostridiales/metabolismo , Microbioma Gastrointestinal , Necesidades Nutricionales , Secuenciación Completa del Genoma , Aminoácidos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Metabolismo de los Hidratos de Carbono , Ácido Cólico/metabolismo , Clostridiales/crecimiento & desarrollo , Medios de Cultivo , Reparación del ADN , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Ácido Desoxicólico/metabolismo , Fermentación , Humanos , Hidroxilación , Análisis de Secuencia de ARN
6.
Plant Cell ; 28(11): 2700-2714, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27803309

RESUMEN

Intense artificial selection over the last 100 years has produced elite maize (Zea mays) inbred lines that combine to produce high-yielding hybrids. To further our understanding of how genome and transcriptome variation contribute to the production of high-yielding hybrids, we generated a draft genome assembly of the inbred line PH207 to complement and compare with the existing B73 reference sequence. B73 is a founder of the Stiff Stalk germplasm pool, while PH207 is a founder of Iodent germplasm, both of which have contributed substantially to the production of temperate commercial maize and are combined to make heterotic hybrids. Comparison of these two assemblies revealed over 2500 genes present in only one of the two genotypes and 136 gene families that have undergone extensive expansion or contraction. Transcriptome profiling revealed extensive expression variation, with as many as 10,564 differentially expressed transcripts and 7128 transcripts expressed in only one of the two genotypes in a single tissue. Genotype-specific genes were more likely to have tissue/condition-specific expression and lower transcript abundance. The availability of a high-quality genome assembly for the elite maize inbred PH207 expands our knowledge of the breadth of natural genome and transcriptome variation in elite maize inbred lines across heterotic pools.


Asunto(s)
Genoma de Planta/genética , Transcriptoma/genética , Zea mays/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Variación Genética/genética
7.
Int J Health Plann Manage ; 34(1): e85-e99, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30182517

RESUMEN

BACKGROUND: Enterprise Architecture (EA) integrates business and technical processes in health information systems (HIS). Low-income and middle-income countries (LMIC) use EA to combine management components with disease tracking and health care service monitoring. Using an EA approach differs by country, addressing specific needs. METHODS: Articles in this review referenced EA, were peer-reviewed or gray literature reports published in 2010 to 2016 in English, and were identified using PubMed, Scopus, Web of Science, and Google Scholar. RESULTS: Fourteen articles described EA use in LMICs. India, Sierra Leone, South Africa, Mozambique, and Rwanda reported building the system to meet country needs and implement a cohesive HIS framework. Jordan and Taiwan focused on specific HIS aspects, ie, disease surveillance and electronic medical records. Five studies informed the context. The Millennium Villages Project employed a "uniform but contextualized" approach to guide systems in 10 countries; Malaysia, Indonesia, and Tanzania used interviews and mapping of existing components to improve HIS, and Namibia used of Activity Theory to identify technology-associated activities to better understand EA frameworks. South Africa, Burundi, Kenya, and Democratic Republic of Congo used EA to move from paper-based to electronic systems. CONCLUSIONS: Four themes emerged: the importance of multiple sectors and data sources, the need for interoperability, the ability to incorporate system flexibility, and the desirability of open group models, data standards, and software. Themes mapped to EA frameworks and operational components and to health system building blocks and goals. Most articles focused on processes rather than outcomes, as countries are engaged in implementation.


Asunto(s)
Países en Desarrollo , Interoperabilidad de la Información en Salud , Sistemas de Información en Salud , Sistemas de Información en Salud/organización & administración , Humanos , Diseño de Software
8.
Altern Lab Anim ; 45(3): 117-158, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28816053

RESUMEN

In 2009, the passing of the Family Smoking Prevention and Tobacco Control Act facilitated the establishment of the FDA Center for Tobacco Products (CTP), and gave it regulatory authority over the marketing, manufacture and distribution of tobacco products, including those termed 'modified risk'. On 4-6 April 2016, the Institute for In Vitro Sciences, Inc. (IIVS) convened a workshop conference entitled, In Vitro Exposure Systems and Dosimetry Assessment Tools for Inhaled Tobacco Products, to bring together stakeholders representing regulatory agencies, academia and industry to address the research priorities articulated by the FDA CTP. Specific topics were covered to assess the status of current in vitro smoke and aerosol/vapour exposure systems, as well as the various approaches and challenges to quantifying the complex exposures in in vitro pulmonary models developed for evaluating adverse pulmonary events resulting from tobacco product exposures. The four core topics covered were: a) Tobacco Smoke and E-Cigarette Aerosols; b) Air-Liquid Interface-In Vitro Exposure Systems; c) Dosimetry Approaches for Particles and Vapours/In Vitro Dosimetry Determinations; and d) Exposure Microenvironment/Physiology of Cells. The 2.5-day workshop included presentations from 20 expert speakers, poster sessions, networking discussions, and breakout sessions which identified key findings and provided recommendations to advance these technologies. Here, we will report on the proceedings, recommendations, and outcome of the April 2016 technical workshop, including paths forward for developing and validating non-animal test methods for tobacco product smoke and next generation tobacco product aerosol/vapour exposures. With the recent FDA publication of the final deeming rule for the governance of tobacco products, there is an unprecedented necessity to evaluate a very large number of tobacco-based products and ingredients. The questionable relevance, high cost, and ethical considerations for the use of in vivo testing methods highlight the necessity of robust in vitro approaches to elucidate tobacco-based exposures and how they may lead to pulmonary diseases that contribute to lung exposure-induced mortality worldwide.


Asunto(s)
Fumar/efectos adversos , Productos de Tabaco/efectos adversos , Pruebas de Toxicidad/métodos , Aerosoles , Animales , Sistemas Electrónicos de Liberación de Nicotina/efectos adversos , Humanos , Técnicas In Vitro , Especificidad de la Especie , Estados Unidos , United States Food and Drug Administration
9.
Mol Pharm ; 13(3): 863-72, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-26833139

RESUMEN

The host- and bacteria-derived extracellular polysaccharide coating of the lung is a considerable challenge in chronic respiratory disease and is a powerful barrier to effective drug delivery. A low molecular weight 12-15-mer alginate oligosaccharide (OligoG CF-5/20), derived from plant biopolymers, was shown to modulate the polyanionic components of this coating. Molecular modeling and Fourier transform infrared spectroscopy demonstrated binding between OligoG CF-5/20 and respiratory mucins. Ex vivo studies showed binding induced alterations in mucin surface charge and porosity of the three-dimensional mucin networks in cystic fibrosis (CF) sputum. Human studies showed that OligoG CF-5/20 is safe for inhalation in CF patients with effective lung deposition and modifies the viscoelasticity of CF-sputum. OligoG CF-5/20 is the first inhaled polymer therapy, represents a novel mechanism of action and therapeutic approach for the treatment of chronic respiratory disease, and is currently in Phase IIb clinical trials for the treatment of CF.


Asunto(s)
Alginatos/química , Fibrosis Quística/tratamiento farmacológico , Mucinas/química , Moco/química , Oligosacáridos/química , Polímeros/farmacología , Adolescente , Adulto , Alginatos/metabolismo , Animales , Enfermedad Crónica , Ensayos Clínicos Fase I como Asunto , Femenino , Ácido Glucurónico/química , Ácido Glucurónico/metabolismo , Ácidos Hexurónicos/química , Ácidos Hexurónicos/metabolismo , Humanos , Masculino , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Mucinas/metabolismo , Moco/metabolismo , Oligosacáridos/metabolismo , Polímeros/química , Ratas , Ratas Sprague-Dawley , Reología , Espectroscopía Infrarroja por Transformada de Fourier , Esputo/química , Porcinos , Adulto Joven
10.
Emerg Med J ; 33(8): 569-72, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26848163

RESUMEN

BACKGROUND: Exsanguination and coagulopathy remain one of the leading causes of preventable trauma related death. Low ionised calcium levels have been associated with hypotension and increased mortality and may inhibit clot formation. Blood product contains citrate that acts as a chelating agent. We hypothesised that trauma patients who have bled are at risk of hypocalcaemia and that receiving any amount of blood product can exacerbate this state. METHODS: A retrospective cohort analysis was performed on all trauma patients who had received early blood product in the ED of a single urban major trauma centre in the UK between 2013 and 2014. Ionised calcium levels were taken from venous blood gases from before and after blood product had been transfused. RESULTS: The study included 55 patients; 36 male (65%), age 33 (16-92) years, median injury severity score (ISS) 24 (4-50), units of blood product received 2 (1-16), overall mortality 18%. Fifty-five per cent patients were hypocalcaemic on arrival, 89% patients were hypocalcaemic after receiving any amount of blood product. There was a statistically significant difference in ionised calcium levels after receiving blood product, pretransfusion 1.11 mmol/L (95% CI 1.09 to 1.14), post-transfusion 0.98 mmol/L (95% CI 0.93 to 1.02) (p<0.001). A fall in calcium was seen after receiving just one unit and the more units of blood product received the greater the fall seen. CONCLUSIONS: Trauma patients that have sustained blood loss are at risk of hypocalcaemia. Ionised calcium levels fall significantly further even after receiving a small amount of blood product. Prompt recognition and early targeted treatment is needed from arrival.


Asunto(s)
Calcio/sangre , Hipocalcemia/etiología , Reacción a la Transfusión , Heridas y Lesiones/sangre , Heridas y Lesiones/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Trastornos de la Coagulación Sanguínea/etiología , Servicio de Urgencia en Hospital , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Centros Traumatológicos
11.
Int J Environ Health Res ; 26(5-6): 483-96, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27295281

RESUMEN

This report describes the use of medications as a proxy when medical record reviews are unavailable, to study the health effects of residents environmentally exposed to air-manganese (n = 185) compared to unexposed residents (n = 90). Participants' current medication lists and medication questionnaire responses were collected in clinical interviews and categorized into 13 domains. Exposed participants reported fewer hours of sleep than controls (6.6 vs. 7.0). The exposed used significantly more medications than unexposed participants (82.2 % vs. 67.8 %) and, when adjusting for age, education, and personal income, also for pain (aOR = 2.40) and hypothyroidism (aOR = 7.03). Exposed participants with higher air-Mn concentrations, monitored for 10 years by the U.S. Environmental Protection Agency, were 1.5 times more likely to take pain medications. The exposed participants take significantly more medications than unexposed participants in the categories of hypothyroidism, pain, supplements, and total medications.


Asunto(s)
Contaminantes Atmosféricos/análisis , Utilización de Medicamentos/estadística & datos numéricos , Exposición a Riesgos Ambientales , Manganeso/análisis , Adulto , Anciano , Monitoreo del Ambiente , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Medicamentos sin Prescripción , Ohio , Preparaciones de Plantas , Medicamentos bajo Prescripción , Población Rural , Encuestas y Cuestionarios
12.
Development ; 139(1): 33-45, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22096075

RESUMEN

Neurog3-induced Dll1 expression in pancreatic endocrine progenitors ostensibly activates Hes1 expression via Notch and thereby represses Neurog3 and endocrine differentiation in neighboring cells by lateral inhibition. Here we show in mouse that Dll1 and Hes1 expression deviate during regionalization of early endoderm, and later during early pancreas morphogenesis. At that time, Ptf1a activates Dll1 in multipotent pancreatic progenitor cells (MPCs), and Hes1 expression becomes Dll1 dependent over a brief time window. Moreover, Dll1, Hes1 and Dll1/Hes1 mutant phenotypes diverge during organ regionalization, become congruent at early bud stages, and then diverge again at late bud stages. Persistent pancreatic hypoplasia in Dll1 mutants after eliminating Neurog3 expression and endocrine development, together with reduced proliferation of MPCs in both Dll1 and Hes1 mutants, reveals that the hypoplasia is caused by a growth defect rather than by progenitor depletion. Unexpectedly, we find that Hes1 is required to sustain Ptf1a expression, and in turn Dll1 expression in early MPCs. Our results show that Ptf1a-induced Dll1 expression stimulates MPC proliferation and pancreatic growth by maintaining Hes1 expression and Ptf1a protein levels.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Páncreas/embriología , Células Secretoras de Polipéptido Pancreático/citología , Células Madre/metabolismo , Factores de Transcripción/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Bromodesoxiuridina , Proteínas de Unión al Calcio , Inmunoprecipitación de Cromatina , Galactósidos , Proteínas de Homeodominio/metabolismo , Inmunohistoquímica , Indoles , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/metabolismo , Células Madre/citología , Factor de Transcripción HES-1
13.
Proc Natl Acad Sci U S A ; 109(20): 7693-8, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22529356

RESUMEN

Using a combination of whole-genome resequencing and high-density genotyping arrays, genome-wide haplotypes were reconstructed for two of the most important bulls in the history of the dairy cattle industry, Pawnee Farm Arlinda Chief ("Chief") and his son Walkway Chief Mark ("Mark"), each accounting for ∼7% of all current genomes. We aligned 20.5 Gbp (∼7.3× coverage) and 37.9 Gbp (∼13.5× coverage) of the Chief and Mark genomic sequences, respectively. More than 1.3 million high-quality SNPs were detected in Chief and Mark sequences. The genome-wide haplotypes inherited by Mark from Chief were reconstructed using ∼1 million informative SNPs. Comparison of a set of 15,826 SNPs that overlapped in the sequence-based and BovineSNP50 SNPs showed the accuracy of the sequence-based haplotype reconstruction to be as high as 97%. By using the BovineSNP50 genotypes, the frequencies of Chief alleles on his two haplotypes then were determined in 1,149 of his descendants, and the distribution was compared with the frequencies that would be expected assuming no selection. We identified 49 chromosomal segments in which Chief alleles showed strong evidence of selection. Candidate polymorphisms for traits that have been under selection in the dairy cattle population then were identified by referencing Chief's DNA sequence within these selected chromosome blocks. Eleven candidate genes were identified with functions related to milk-production, fertility, and disease-resistance traits. These data demonstrate that haplotype reconstruction of an ancestral proband by whole-genome resequencing in combination with high-density SNP genotyping of descendants can be used for rapid, genome-wide identification of the ancestor's alleles that have been subjected to artificial selection.


Asunto(s)
Cruzamiento/métodos , Bovinos/genética , Genoma/genética , Haplotipos/genética , Selección Genética , Animales , Secuencia de Bases , Estudios de Asociación Genética/veterinaria , Genotipo , Masculino , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple/genética , Análisis de Secuencia de ADN
14.
Emerg Med J ; 32(6): 463-7, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24981009

RESUMEN

OBJECTIVE: Intraosseous access (IO) is becoming increasingly accepted in adult populations as an alternative to peripheral vascular access; however, there is still insufficient evidence in large patient groups supporting its use. METHODS: Retrospective review. This paper reports on the use of IO devices over a 7-year period from August 2006 to August 2013 during combat operations in Afghanistan. A database search of the Joint Theatre Trauma Registry (JTTR) was carried out looking for all the incidences of IO access use during this time. Excel (Microsoft) was used to manage the dataset and perform descriptive statistics on the patient demographics, injuries, treatments and complications that were retrieved. RESULTS: 1014 IO devices were used in 830 adult patients with no major complications. The rate of minor complications, the majority of which were device failure, was 1.38%. 5124 separate infusions of blood products or fluids occurred via IO access, with 36% being of packed red cells. On average, each casualty received 6.95 different infusions of blood products and fluids, and 3.28 separate infusions of drugs through IO access. 32 different drugs were infused to 367 patients via IO, the most frequent being anaesthetic agents. IO access was used in the prehospital environment, during tactical helicopter evacuation and within hospitals. CONCLUSIONS: IO access can be used to administer a wide variety of life-saving medications quickly, easily and with low-complication rates. This highlights its valuable role as an alternative method of obtaining vascular access, vital when resuscitating the critically injured trauma patient.


Asunto(s)
Servicios Médicos de Urgencia , Infusiones Intraóseas/instrumentación , Heridas y Lesiones/terapia , Adolescente , Adulto , Anciano , Enfermedad Crítica , Humanos , Infusiones Intraóseas/efectos adversos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Resucitación , Estudios Retrospectivos , Adulto Joven
15.
Am J Respir Cell Mol Biol ; 50(3): 483-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24074505

RESUMEN

Pseudomonas aeruginosa (PA) biofilm-associated infections are a common cause of morbidity in chronic respiratory disease and represent a therapeutic challenge. Recently, the ability of a novel alginate oligomer (OligoG) to potentiate the effect of antibiotics against gram-negative, multi-drug-resistant bacteria and inhibit biofilm formation in vitro has been described. Interaction of OligoG with the cell surface of PA was characterized at the nanoscale using atomic force microscopy (AFM), zeta potential measurement (surface charge), and sizing measurements (dynamic light scattering). The ability of OligoG to modify motility was studied in motility assays. AFM demonstrated binding of OligoG to the bacterial cell surface, which was irreversible after exposure to hydrodynamic shear (5,500 × g). Zeta potential analysis (pH 5-9; 0.1-0.001 M NaCl) demonstrated that binding was associated with marked changes in the bacterial surface charge (-30.9 ± 0.8 to -47.0 ± 2.3 mV; 0.01 M NaCl [pH 5]; P < 0.001). Sizing analysis demonstrated that alteration of surface charge was associated with cell aggregation with a 2- to 3-fold increase in mean particle size at OligoG concentrations greater than 2% (914 ± 284 to 2599 ± 472 nm; 0.01 M NaCl [pH 5]; P < 0.001). These changes were associated with marked dose-dependent inhibition in bacterial swarming motility in PA and Burkholderia spp. The ability of OligoG to bind to a bacterial surface, modulate surface charge, induce microbial aggregation, and inhibit motility represents important direct mechanisms by which antibiotic potentiation and biofilm disruption is affected. These results highlight the value of combining multiple nanoscale technologies to further our understanding of the mechanisms of action of novel antibacterial therapies.


Asunto(s)
Alginatos/farmacología , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Nanomedicina , Pseudomonas aeruginosa/efectos de los fármacos , Alginatos/química , Antibacterianos/química , Burkholderia/efectos de los fármacos , Burkholderia/crecimiento & desarrollo , Química Farmacéutica , Relación Dosis-Respuesta a Droga , Ácido Glucurónico/química , Ácido Glucurónico/farmacología , Ácidos Hexurónicos/química , Ácidos Hexurónicos/farmacología , Luz , Microscopía de Fuerza Atómica , Nanomedicina/métodos , Nanopartículas , Pseudomonas aeruginosa/fisiología , Dispersión de Radiación , Propiedades de Superficie
16.
Environ Microbiol ; 16(6): 1695-708, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24238218

RESUMEN

A low-diversity microbial community, dominated by the γ-proteobacterium Halomonas sulfidaeris, was detected in samples of warm saline formation porewater collected from the Cambrian Mt. Simon Sandstone in the Illinois Basin of the North American Midcontinent (1.8 km/5872 ft burial depth, 50°C, pH 8, 181 bars pressure). These highly porous and permeable quartz arenite sandstones are directly analogous to reservoirs around the world targeted for large-scale hydrocarbon extraction, as well as subsurface gas and carbon storage. A new downhole low-contamination subsurface sampling probe was used to collect in situ formation water samples for microbial environmental metagenomic analyses. Multiple lines of evidence suggest that this H. sulfidaeris-dominated subsurface microbial community is indigenous and not derived from drilling mud microbial contamination. Data to support this includes V1-V3 pyrosequencing of formation water and drilling mud, as well as comparison with previously published microbial analyses of drilling muds in other sites. Metabolic pathway reconstruction, constrained by the geology, geochemistry and present-day environmental conditions of the Mt. Simon Sandstone, implies that H. sulfidaeris-dominated subsurface microbial community may utilize iron and nitrogen metabolisms and extensively recycle indigenous nutrients and substrates. The presence of aromatic compound metabolic pathways suggests this microbial community can readily adapt to and survive subsurface hydrocarbon migration.


Asunto(s)
Halomonas/genética , Microbiología del Agua , Genes Bacterianos , Illinois , Redes y Vías Metabólicas/genética , Metagenoma , Microbiota/genética , Anotación de Secuencia Molecular , Datos de Secuencia Molecular , Filogenia , Cuarzo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
17.
J R Army Med Corps ; 160(4): 271-2, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24155347

RESUMEN

This paper suggests that 1 g tranexamic acid should be incorporated as an intramuscular auto-injector and issued to combat troops for self- or buddy-administration in the event of suffering severe injury. Early administration of tranexamic acid has shown to be beneficial in preventing death from bleeding in trauma patients in both the military and the civilian settings. Tranexamic acid is cheap, safe, easy to administer and saves lives. Future conflicts may be characterised by prolonged pre-hospital times and delayed access to advanced medical care. The use of this drug is the next logical step in reducing combat trauma deaths.


Asunto(s)
Antifibrinolíticos/administración & dosificación , Medicina Militar/métodos , Personal Militar , Ácido Tranexámico/administración & dosificación , Antifibrinolíticos/efectos adversos , Antifibrinolíticos/uso terapéutico , Estudios de Factibilidad , Hemorragia/tratamiento farmacológico , Hemorragia/prevención & control , Humanos , Ácido Tranexámico/efectos adversos , Ácido Tranexámico/uso terapéutico
18.
Genesis ; 51(6): 436-42, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23441020

RESUMEN

Cre/LoxP-mediated recombination allows for conditional gene activation or inactivation. When combined with an independent lineage-tracing reporter allele, this technique traces the lineage of presumptive genetically modified Cre-expressing cells. Several studies have suggested that floxed alleles have differential sensitivities to Cre-mediated recombination, which raises concerns regarding utilization of Cre-reporters to monitor recombination of other floxed loci of interest. Here, we directly investigate the recombination correlation, at cellular resolution, between several floxed alleles induced by Cre-expressing mouse lines. The recombination correlation between different reporter alleles varied greatly in otherwise genetically identical cell types. The chromosomal location of floxed alleles, distance between LoxP sites, sequences flanking the LoxP sites, and the level of Cre activity per cell all likely contribute to observed variations in recombination correlation. These findings directly demonstrate that, due to non-parallel recombination events, commonly available Cre reporter mice cannot be reliably utilized, in all cases, to trace cells that have DNA recombination in independent-target floxed alleles, and that careful validation of recombination correlations are required for proper interpretation of studies designed to trace the lineage of genetically modified populations, especially in mosaic situations.


Asunto(s)
Genes Reporteros , Integrasas/genética , Recombinación Genética , Activación Transcripcional , Alelos , Animales , Linaje de la Célula , Ratones , Ratones Transgénicos
19.
Biofouling ; 29(4): 413-21, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23574333

RESUMEN

The influence of a novel, safe antibiofilm therapy on the mechanical properties of Pseudomonas aeruginosa and Acinetobacter baumannii biofilms in vitro was characterized. A multiscale approach employing atomic force microscopy (AFM) and rheometry was used to quantify the mechanical disruption of the biofilms by a therapeutic polymer based on a low-molecular weight alginate oligosaccharide (OligoG). AFM demonstrated structural alterations in the biofilms exposed to OligoG, with significantly lower Young's moduli than the untreated biofilms, (149 MPa vs 242 MPa; p < 0.05), a decreased resistance to hydrodynamic shear and an increased surface irregularity (Ra) in the untreated controls (35.2 nm ± 7.6 vs 12.1 nm ± 5.4; p < 0.05). Rheology demonstrated that increasing clinically relevant concentrations of OligoG (<10%) were associated with an increasing phase angle (δ) over a wide range of frequencies (0.1-10 Hz). These results highlight the utility of these techniques for the study of three-dimensional biofilms and for quantifying novel disruption therapies in vitro.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Alginatos/farmacología , Biopelículas/efectos de los fármacos , Oligosacáridos/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Acinetobacter baumannii/fisiología , Alginatos/química , Alginatos/aislamiento & purificación , Adhesión Bacteriana/efectos de los fármacos , Fenómenos Biomecánicos , Módulo de Elasticidad , Hidrodinámica , Laminaria/química , Pruebas de Sensibilidad Microbiana , Oligosacáridos/química , Pseudomonas aeruginosa/fisiología , Reología/métodos , Resistencia al Corte/efectos de los fármacos , Estrés Mecánico
20.
Biomater Transl ; 4(1): 18-26, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37206302

RESUMEN

Mechanobiological study of chondrogenic cells and multipotent stem cells for articular cartilage tissue engineering (CTE) has been widely explored. The mechanical stimulation in terms of wall shear stress, hydrostatic pressure and mechanical strain has been applied in CTE in vitro. It has been found that the mechanical stimulation at a certain range can accelerate the chondrogenesis and articular cartilage tissue regeneration. This review explicitly focuses on the study of the influence of the mechanical environment on proliferation and extracellular matrix production of chondrocytes in vitro for CTE. The multidisciplinary approaches used in previous studies and the need for in silico methods to be used in parallel with in vitro methods are also discussed. The information from this review is expected to direct facial CTE research, in which mechanobiology has not been widely explored yet.

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