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Human usage of coastal water bodies continues to increase and many invertebrates face a broad suite of anthropogenic stressors (e.g., warming, pollution, acidification, fishing pressure). Underwater sound is a stressor that continues to increase in coastal areas, but the potential impact on invertebrates is not well understood. In addition to masking natural sound cues which may be important for behavioral interactions, there is a small but increasing body of scientific literature indicating sublethal physiological stress may occur in invertebrates exposed to high levels of underwater sound, particularly low frequency sounds such as vessel traffic, construction noise, and some types of sonar. Juvenile and sub-adult blue crabs (Callinectes sapidus) and American lobsters (Homarus americanus) were exposed to simulated low-frequency vessel noise (a signal was low-pass filtered below 1 kHz to ensure low-frequency content only) and mid-frequency sonar (a 1-s 1.67 kHz continuous wave pulse followed by a 2.5 to 4.0 kHz 1-s linear frequency modulated chirp) and behavioral response (the animal's activity level) was quantified during and after exposure using EthoVision XT™ from overhead video recordings. Source noise was quantified by particle acceleration and pressure. Physiological response to the insults (stress and recovery) were also quantified by measuring changes in hemolymph heat shock protein (HSP27) and glucose over 7 days post-exposure. In general, physiological indicators returned to baseline levels within approximately 48 h, and no observable difference in mortality between treatment and control animals was detected. However, there was a consistent amplified hemolymph glucose signal present 7 days after exposure for those animals exposed to mid-frequency sound and there were changes to C. sapidus competitive behavior within 24 h of exposure to sound. These results stress the importance of considering the impacts of underwater sound among the suite of stressors facing marine and estuarine invertebrates, and in the discussion of management actions such as protected areas, impact assessments, and marine spatial planning efforts.
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Ruído , Som , Animais , Humanos , Ruído/efeitos adversos , Invertebrados , Espectrografia do SomRESUMO
Abstract Background: Paragonimus spp. are trematode parasites that infect human populations worldwide. It is believed that infection rates within Asia reach five to ten percent of the total population. Three of the largest areas of possible infection are Asia, Central and South America as well as Africa, where the total population at risk is estimated to be 293 million people. Humans are infected via ingestion of raw or undercooked decapod crustaceans. Objective: To identify the presence of Paragonimus spp. in crabs from Bogotá, Colombia. Methods: The native crab Neostrengeria macropa and the aquatic invasive crayfish Procambarus clarkii in Bogotá, Colombia, were collected from local markets, pet stores and waterways and dissected to assess the presence of Paragonimus spp. Results: The native crab species, N. macropa (n=29) had an infection prevalence of 17.2%, while the invasive crayfish species, P. clarkii (n=22), had a prevalence of 36.4% combined from both field captured animals and purchased samples. Conclusion: Although the estimated prevalence is lower compared to previous studies in other cities of Colombia, Paragonimus represent a risk to human health. Several environmental factors may contribute to the difference in prevalence including collecting season, rainfall, temperature, altitude and the El Niño Southern Oscillation.
Resumen Antecedentes: Los Paragonimus spp. constituyen un grupo de parásitos tremátodos que infectan a humanos en todo el mundo. Se considera que entre 5 y 10% de la población humana de Asia está infectada. Las áreas con mayor posibilidad de infección son Asia, Centro y Sur América, así como África. Se estima que 293 millones de personas están en riesgo de infección. Los humanos se pueden infectar al consumir crustáceos decápodos crudos. Objetivo: Identificar la presencia de Paragonimus spp. en crustáceos en Bogotá, Colombia. Métodos: Una muestra de cangrejos nativos Neostrengeria macropa y de decápodos invasores Procambarus clarkii fue colectada tanto en mercados locales de Bogotá, como en tiendas de mascotas, ríos, y quebradas. Posteriromente fueron diseccionados para detectar la presencia de Paragonimus spp. Resultados: La prevalencia de la infección en N. macropa (n=29) fue de 17,2%, y en la especie invasora, P. clarkii (n=22), fue de 36,4% (porcentaje combinado de los animales colectados en el campo y los comprados en tiendas). Conclusión: Aunque la prevalencia en este estudio fue más baja que la de otras investigaciones relacionadas, se considera que existe riesgo para la salud humana. Es probable que algunos factores medio ambientales hayan contribuido a la diferencia, incluyendo: temporada de colecta, nivel de lluvias, temperatura, altura, y el fenómeno El Niño.
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The dearth of new antibiotics in the face of widespread antimicrobial resistance makes developing innovative strategies for discovering new antibiotics critical for the future management of infectious disease. Understanding the genetics and evolution of antibiotic producers will help guide the discovery and bioengineering of novel antibiotics. We discovered an isolate in Alaskan boreal forest soil that had broad antimicrobial activity. We elucidated the corresponding antimicrobial natural products and sequenced the genome of this isolate, designated Streptomyces sp. 2AW. This strain illustrates the chemical virtuosity typical of the Streptomyces genus, producing cycloheximide as well as two other biosynthetically unrelated antibiotics, neutramycin, and hygromycin A. Combining bioinformatic and chemical analyses, we identified the gene clusters responsible for antibiotic production. Interestingly, 2AW appears dissimilar from other cycloheximide producers in that the gene encoding the polyketide synthase resides on a separate part of the chromosome from the genes responsible for tailoring cycloheximide-specific modifications. This gene arrangement and our phylogenetic analyses of the gene products suggest that 2AW holds an evolutionarily ancestral lineage of the cycloheximide pathway. Our analyses support the hypothesis that the 2AW glutaramide gene cluster is basal to the lineage wherein cycloheximide production diverged from other glutarimide antibiotics. This study illustrates the power of combining modern biochemical and genomic analyses to gain insight into the evolution of antibiotic-producing microorganisms.
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Natural products remain an important source of new therapeutics for emerging drug-resistant pathogens like Candida albicans, which particularly affects immunocompromised patients. A bioactive 3-decalinoyltetramic acid, pyrrolocin A, was isolated from extracts of a novel Amazonian fungal endophyte, E6927E, of the Diaporthales family. The structure of the natural product was solved using NMR and CD spectroscopy and it is structurally related to the fungal setins, equisetin and phomasetin, which are well-characterized tetramic acid antibiotics specific for Gram-positive organisms. We show that the compound inhibits growth of Staphylococcus aureus and Enterococcus faecalis. It shows selective and potent bioactivity against fungal strains, with an MIC of 4 µg/mL for C. albicans, 100 µg/mL for Aspergillus sp. and greater than 100 µg/mL for Saccharomyces cerevisiae. Further, the compound is less toxic to mammalian cells (IC50 = 150 µg/mL), with an inhibitory concentration greater than forty times that for C. albicans. Pyrrolocin A retained potent activity against eight out of seventeen strains of clinical Candida sp. isolates tested.
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Ascomicetos/química , Endófitos/química , Pirrolidinonas/química , Antibacterianos/química , Antibacterianos/farmacologia , Ascomicetos/genética , Bactérias/efeitos dos fármacos , DNA Fúngico/genética , Ficus/microbiologia , Genômica , Testes de Sensibilidade Microbiana , Estrutura Molecular , FilogeniaRESUMO
BACKGROUND: For human papillomavirus (HPV) DNA detection, specimen collection and transportation using a dry swab without transport medium has advantages, in various situations, over liquid media. OBJECTIVE: In this pilot study we evaluated whether a dry cervical sample taken with a flocked swab (dry sample) is a valid alternative for HPV DNA testing compared with the standard practice of a wet sample taken with a cyto-broom placed directly into liquid media (wet sample). STUDY DESIGN: Women attending the dysplasia clinic at the Royal Women's Hospital, Melbourne Australia between November 2013 and February 2014 were enrolled. During colposcopic examination, a practitioner collected wet and dry cervical samples, with the order of collection randomised. In the laboratory both samples were left for a week before being tested for 14 high-risk HPV types using the Roche Cobas 4800 test. RESULTS: Overall, 209 had valid HPV results from both samples. The observed agreement for HPV detection between wet and dry samples was 92.8% and kappa was 0.85 (95% confidence interval (95% CI): 0.78-0.92). There was no statistical difference in the percent HPV positive for each sample (p = 0.30). HPV testing of the dry sample had an 88.5% (95% CI: 79.9-94.3%) sensitivity for HPV detected using the wet specimen. For the HPV results categorized hierarchically, there was 92.8% overall agreement and a kappa of 0.87 (95% CI = 0.80-0.93) for the paired results. CONCLUSION: Using dry flocked swabs to collect cervical cells is a valid alternative to collecting wet samples for HPV DNA testing using a PCR based test.
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Colo do Útero/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Manejo de Espécimes/métodos , Feminino , Testes de DNA para Papilomavírus Humano , Humanos , Infecções por Papillomavirus/virologia , Projetos Piloto , Distribuição Aleatória , Sensibilidade e Especificidade , Esfregaço Vaginal/métodosRESUMO
Macrophages have an important role in the maintenance of tissue homeostasis. To perform this function, macrophages must have the capacity to monitor the functional states of their 'client cells': namely, the parenchymal cells in the various tissues in which macrophages reside. Tumours exhibit many features of abnormally developed organs, including tissue architecture and cellular composition. Similarly to macrophages in normal tissues and organs, macrophages in tumours (tumour-associated macrophages) perform some key homeostatic functions that allow tumour maintenance and growth. However, the signals involved in communication between tumours and macrophages are poorly defined. Here we show that lactic acid produced by tumour cells, as a by-product of aerobic or anaerobic glycolysis, has a critical function in signalling, through inducing the expression of vascular endothelial growth factor and the M2-like polarization of tumour-associated macrophages. Furthermore, we demonstrate that this effect of lactic acid is mediated by hypoxia-inducible factor 1α (HIF1α). Finally, we show that the lactate-induced expression of arginase 1 by macrophages has an important role in tumour growth. Collectively, these findings identify a mechanism of communication between macrophages and their client cells, including tumour cells. This communication most probably evolved to promote homeostasis in normal tissues but can also be engaged in tumours to promote their growth.
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Ácido Láctico/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Arginase/genética , Arginase/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Comunicação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Feminino , Glicólise , Homeostase , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácido Láctico/farmacologia , Masculino , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , RNA Mensageiro/genética , Solubilidade , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Endophytes isolated from tropical plants represent a largely untapped reservoir of bioactive secondary metabolites. We screened a library of fungal endophyte extracts for inhibition of the plant pathogen, Pythium ultimum, and purified an active compound using bioassay-guided fractionation. A new nonenolide, (4S,7S,8S,9R)-4-O-succinyl-7,8-dihydroxy-9-heptyl-nonen-9-olide, was isolated and named xyolide. The structure was elucidated by a combination of 1D and 2D NMR methods and the absolute configuration was determined by exciton-coupled circular dichroism. The MIC of xyolide against P. ultimum was 425 µM.
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Many modern diagnostic and surgical procedures rely heavily on the use of ionizing radiation. These procedures include computed tomography, nuclear medicine procedures, interventional radiology, and cardiac catheterization and electrophysiology procedures. Recent trends toward increased patient visits and patients with multiple challenging comorbidities have meant that anesthesia providers are increasingly required to provide services in the ancillary areas using ionizing radiation. As a result, anesthesia providers are at a greater-than-ever risk for excessive radiation doses. An overview of some of the basic principles of radiation biology, radiation physics, and radiation protection and specific guidelines related to radiation exposure and pregnancy are described. The effects of radiation exposure are cumulative and permanent, and an understanding of these principles and practices will help anesthesia providers keep their occupational exposure to a minimum.
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Enfermeiros Anestesistas , Doenças Profissionais/prevenção & controle , Doses de Radiação , Monitoramento de Radiação , Gestão da Segurança , Comorbidade , Educação Continuada em Enfermagem , Feminino , Humanos , Doenças Profissionais/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/prevenção & controle , Fatores de RiscoRESUMO
BACKGROUND: Archival Papanicolaou (Pap)-stained cervical cytology tests may be the only source of a clinical sample for the evaluation of previous human papillomavirus (HPV) infection. Pap tests are ideal because the majority of women in countries with comprehensive screening programs would have had several collected and stored. METHODS: In the current study, HPV detection and genotyping were compared in samples collected from a conventionally fixed Pap test with those collected using an endocervical brush and collected in PreservCyt (liquid-based) in 87 women undergoing management for a high-grade Pap test abnormality. Cytology slides were scanned to create high-resolution digital images before the removal of cells because the DNA extraction process resulted in the destruction of the cells from the original sample. RESULTS: All previously identified high-grade abnormalities on the Pap tests were detectable on the digital images. ß-globin was detected in all extracted Pap tests, indicating the presence of recoverable, amplifiable DNA. A total of 62 (71.3%) and 59 (67.8%) tests were found to have high-risk (HR) HPV detected on PreservCyt and fixed Pap test slides, respectively, with >87% concordance for the detection of HR HPV genotypes. Complete HPV genotyping concordance was observed in 62% and was partial in 26% of sample pairs, with very good agreement for HPV types 16 and 18 (κ = 0.850 and 0.903, respectively). Only 1 Pap test slide was found to be positive whereas the PreservCyt had no detectable HPV DNA, demonstrating a low false-positive rate (1%). CONCLUSIONS: The results of the current study confirm that imaging and subsequent HPV detection and genotyping in archival cervical smears can offer accuracy in HPV detection that is comparable to endocervical brush-collected PreservCyt samples.
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DNA Viral/análise , Teste de Papanicolaou , Papillomaviridae/isolamento & purificação , Esfregaço Vaginal , Feminino , Genótipo , Humanos , Papillomaviridae/classificação , Papillomaviridae/genéticaRESUMO
BACKGROUND: Traditionally, acupuncturists manipulate needles to enhance sensations referred to as de qi or 'acupuncture needle sensation'. Acupuncture needle sensations are complex and quantifying the experience has been difficult. The aim of this crossover study was to measure self-reported needle sensation during deep and bi-directional rotated needling in 15 healthy volunteers. METHODS: Each participant received an experimental intervention consisting of superficial needling followed by deep needling and then deep needling with bi-directional rotation. The control intervention consisted of superficial needling, followed by mock deep needling and then mock bi-directional rotation of the needle. The intensity of overall needle sensation was measured using a visual analogue scale (VAS). The subjective acupuncture sensation scale was used to capture component sensations. RESULTS: VAS scores were higher during 'deep' needle penetration when compared to superficial needling with mock deep insertion (p=0.0002). VAS scores were also higher during deep needling with bi-directional rotation compared to superficial needling with mock bi-directional rotation (p<0.0001). There were higher scores for total component sensation scores and for the sensation of throbbing during the deep needling with bi-directional rotation (p=0.001) when compared to superficial needling with mock bi-directional rotation. Tentative evidence that bi-directional needle rotation generated stabbing, tingling, heaviness, soreness and aching was also found. CONCLUSION: Bi-directional rotation of a needle inserted into deep soft tissue produced higher acupuncture needle sensation intensities when compared to superficial needle insertion with mock deep penetration and bi-directional rotation.
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Pontos de Acupuntura , Terapia por Acupuntura/instrumentação , Agulhas/efeitos adversos , Dor/diagnóstico , Propriocepção/fisiologia , Pele/inervação , Terapia por Acupuntura/efeitos adversos , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Dor/etiologia , Medição da Dor , Valores de Referência , Projetos de Pesquisa , Inquéritos e QuestionáriosRESUMO
RATIONALE: Lung inflammation and injury is critical in cystic fibrosis. An ideal antiinflammatory agent has not been identified but inhaled corticosteroids are widely used despite lack of evidence. OBJECTIVES: To test the safety of withdrawal of inhaled corticosteroids with the hypothesis this would not be associated with an earlier onset of acute chest exacerbations. METHODS: Multicenter randomized double-blind placebo-controlled trial in 18 pediatric and adult UK centers. Eligibility criteria included age>6.0 yr, FEV1>or=40% predicted, and corticosteroid use>3 mo. During the 2-mo run-in period, all patients received fluticasone; they then took either fluticasone or placebo for 6 mo. MEASUREMENTS AND MAIN RESULTS: Fluticasone group: n=84, median age 14.6 yr, mean (SD) FEV1 76% (18); placebo group: n=87, median age 15.8 yr, mean (SD) FEV1 76% (18). There was no difference in time to first exacerbation (primary outcome) with hazard ratio (95% confidence interval) of 1.07 (0.68 to 1.70) for fluticasone versus placebo. There was no effect of age, atopy, corticosteroid dose, FEV1, or Pseudomonas aeruginosa status. There was no change in lung function or differences in antibiotic or rescue bronchodilator use. Fewer patients in the fluticasone group withdrew from the study due to lung-related adverse events (9 vs. 15%); with a relative risk (95% confidence interval) of 0.59 (0.23-1.48) fluticasone versus placebo. CONCLUSIONS: In this study population (applicable to 40% of patients with cystic fibrosis in the UK), it appears safe to consider stopping inhaled corticosteroids. Potential advantages will be to reduce the drug burden on patients, reduce adverse effects, and make financial savings.
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Corticosteroides/uso terapêutico , Androstadienos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Fibrose Cística/tratamento farmacológico , Suspensão de Tratamento , Administração por Inalação , Adolescente , Corticosteroides/administração & dosagem , Adulto , Fatores Etários , Androstadienos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Asma/tratamento farmacológico , Asma/fisiopatologia , Broncodilatadores/uso terapêutico , Criança , Fibrose Cística/fisiopatologia , Método Duplo-Cego , Estudos de Viabilidade , Feminino , Fluticasona , Seguimentos , Volume Expiratório Forçado/efeitos dos fármacos , Volume Expiratório Forçado/fisiologia , Humanos , Pulmão/microbiologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Placebos , Pseudomonas aeruginosa/isolamento & purificação , SegurançaRESUMO
High-frequency chest compressions (HFCC) have been suggested as an alternative to conventional chest physiotherapy to aid sputum clearance in patients with cystic fibrosis (CF). We aimed to compare the active cycle of breathing techniques (ACBT) with the Hayek Oscillator Cuirass, performing HFCC on secretion clearance in children with CF during an exacerbation. Ten children (7 males; median age, 14 years; range, 9-16) received either two supervised sessions using HFCC or two self-treatment ACBT sessions in random order on successive days. Baseline pulmonary function was similar prior to treatments. Sputum weight increased significantly with ACBT compared with HFCC during treatment (5.2 g vs. 1.1 g, P < 0.005, morning; 4.1 g vs. 0.7 g, P < 0.01, afternoon). Pulmonary function improved significantly after morning ACBT (forced vital capacity (FVC): 2.67 l to 2.76 l, P < 0.03; forced expiratory volume in 1 sec (FEV1): 1.59 l to 1.62 l, P < 0.03). Following afternoon ACBT, there was a significant increase in FVC (2.64 to 2.79, P < 0.02), but no significant change in FEV1. Pulmonary function did not change at any time following HFCC. Compared with ACBT, HFCC by Hayek Cuirass is not an effective airway clearance treatment modality for children with CF during an infective exacerbation.