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1.
Nature ; 614(7949): 659-663, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623548

RESUMO

Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species-in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5-5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec's PRISM mode9 as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10-12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2 (28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2 feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2 (2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST's sensitivity to a rich diversity of exoplanet compositions and chemical processes.

2.
Lett Appl Microbiol ; 71(2): 210-217, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32304584

RESUMO

The effects of soil type and temperature on the survival of a cocktail of five Salmonella enterica serotypes (Enteritidis, Infantis, Montevideo, Typhimurium and Zanzibar) in manure-amended soils under controlled laboratory conditions was assessed. Containers of clay loam or sandy soil, unaltered or amended with 2% (w/w) poultry manure, were inoculated with S. enterica (~5 log10 CFU per gram) and held at 5, 21 or 37°C for 6 weeks. Statistical analysis of the persistence of S. enterica identified a significant three-way interaction between soil type, manure amendment and temperature. Clay loam soils and lower temperatures tended to support S. enterica persistence over 6 weeks with only 1- and 2-log reductions respectively. In contrast, sand and higher temperatures resulted in a 4-log and either 3- to 4-log reductions respectively. Manure amendment had an overarching effect of reducing die-off of S. enterica in comparison with unamended soils. This study highlights that a large component of variation of the rate of S. enterica reduction in soils may be attributed to combinations of environmental factors, in particular, soil type and temperature. It further underscores the importance of risk management strategies and industry guidelines based on local data and that reflect the diversity of prevailing horticultural production environments. SIGNIFICANCE AND IMPACT OF THE STUDY: The persistence of Salmonella enterica in soil environments was shown to be significantly influenced by a range of individual and interacting environmental effects, including temperature, soil type and amendment addition. This indicates that current horticultural food safety management systems which employ a uniform prescribed exclusion period between application of manure and time of harvest may be unfit for purpose under certain conditions by either underestimating or overestimating pathogen die-off. These findings support exclusion periods that account for a range of environmental factors including temperature, soil type and growing region that may be more appropriate to manage microbiological risks associated with soil which has been amended with manure.


Assuntos
Esterco/microbiologia , Aves Domésticas/microbiologia , Salmonella enterica/crescimento & desenvolvimento , Salmonella enterica/isolamento & purificação , Animais , Temperatura Alta , Salmonella enterica/classificação , Solo/química , Microbiologia do Solo
3.
Public Health ; 168: 76-82, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30708198

RESUMO

OBJECTIVE: The objective of this study was to examine the association between childhood injury and health outcomes among survivors and their mothers using a national survey in the United States (US). STUDY DESIGN: This was a longitudinal analysis of a nationally representative sample. METHODS: Secondary analysis of the 1997-2013 Medical Expenditure Panel Survey (MEPS) was performed. Children (aged 2-18 years) with or without injuries were followed up for two years. Injuries captured in the study were those associated with at least one hospitalization, emergency department visit, or office-based visit. Outcome measures were child and maternal general and mental health status. Multiple mixed-logistic regressions were used with suboptimal health defined as the response of poor or fair health versus good, very good, or excellent health. RESULTS: Of the 63,422 children analyzed, 3251 (4.9%) were injured, representing 3.6 million US children. Injured children were more likely to be male, white, and older than those without injuries (P < 0.01). About a fifth of injured children suffered head injuries. Injuries were strongly associated with suboptimal general and mental health status in children (adjusted odds ratios [AORs], 1.35 and 1.36, respectively, P < 0.05). Mothers of children with injuries were also more likely to report suboptimal mental health (AOR, 1.30, P < 0.05). CONCLUSION: Injuries among children are associated with lasting adverse effects in general and mental health. To improve health outcomes of pediatric injuries, further follow-up care may be needed to ensure that they return to pre-injury health levels. These results highlight the importance of primary prevention and the long-term impact of injuries on the health of children and their mothers.


Assuntos
Saúde da Criança/estatística & dados numéricos , Saúde Materna/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Inquéritos Epidemiológicos , Humanos , Masculino , Estados Unidos/epidemiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-31354384

RESUMO

Cognitive impairments seen in people living with HIV (PLWH) are associated with difficulties in everyday functioning, specifically driving. This study utilized speed of processing cognitive remediation therapy (SOP-CRT) with transcranial direct current stimulation (tDCS) to gauge the feasibility and impact on simulated driving. Thirty PLWH (M age = 54.53, SD = 3.33) were randomly assigned to either: sham tDCS SOP-CRT or active tDCS SOP-CRT. Seven indicators of simulated driving performance and safety were obtained. Repeated measures ANOVAs controlling for driver's license status (valid and current license or expired/no license) revealed a large training effect on average driving speed. Participants who received active tDCS SOP-CRT showed a slower average driving speed (p = 0.020, d = 0.972) than those who received sham tDCS SOP-CRT. Non-significant small-to-medium effects were seen for driving violations, collisions, variability in lane positioning, and lane deviations. Combination tDCS SOP-CRT was found to increase indices of cautionary simulated driving behavior. Findings reveal a potential avenue of intervention and rehabilitation for improving driving safety among vulnerable at-risk populations, such as those aging with chronic disease.

5.
Vet Pathol ; 54(3): 549-562, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28438110

RESUMO

Lassa virus (LASV) infection causes an acute, multisystemic viral hemorrhagic fever that annually infects an estimated 100 000 to 300 000 persons in West Africa. This pathogenesis study evaluated the temporal progression of disease in guinea pigs following aerosol and subcutaneous inoculation of the Josiah strain of LASV as well as the usefulness of Strain 13 guinea pigs as an animal model for Lassa fever. After experimental infection, guinea pigs ( Cavia porcellus; n = 67) were serially sampled to evaluate the temporal progression of infection, gross and histologic lesions, and serum chemistry and hematologic changes. Guinea pigs developed viremia on day 5 to 6 postexposure (PE), with clinical signs appearing by day 7 to 8 PE. Complete blood counts revealed lymphopenia and thrombocytopenia. Gross pathologic findings included skin lesions and congested lungs. Histologic lesions consisted of cortical lymphoid depletion by day 6 to 7 PE with lymphohistiocytic interstitial pneumonia at 7 to 8 days PE. Scattered hepatocellular degeneration and cell death were also noted in the liver and, to a lesser extent, in other tissues including the haired skin, lung, heart, adrenal gland, lymph nodes, thymus, and spleen. The first cell types to demonstrate staining for viral antigen were fibroblastic reticular cells and macrophages/dendritic cells in the lymph nodes on day 5 to 6 PE. This study demonstrates similarities between Lassa viral disease in human infections and experimental guinea pig infection. These shared pathologic characteristics support the utility of guinea pigs as an additional animal model for vaccine and therapeutic development under the Food and Drug Administration's Animal Rule.


Assuntos
Cobaias/virologia , Febre Lassa/veterinária , Vírus Lassa , Glândulas Suprarrenais/patologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Rim/patologia , Febre Lassa/patologia , Fígado/patologia , Pulmão/patologia , Linfonodos/patologia , Masculino , Miocárdio/patologia , Pele/patologia , Baço/patologia , Timo/patologia , Viremia/patologia , Viremia/veterinária
6.
Environ Microbiol ; 18(6): 2010-24, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26768496

RESUMO

A recent large-scale assessment of bacterial communities across a range of UK soil types showed that bacterial community structure was strongly determined by soil pH. We analysed a data set of eukaryotic 454 sequencing 18S rDNA from the surveyed samples and showed significant differences in eukaryotic assemblages according to pH class, mostly between low pH and higher pH soils. Soil eukaryote communities (per sample) differed most at the taxonomic rank approximating to order level. Taxonomies assigned with the Protist Ribosomal Reference and the Silva 119 databases were taxonomically inconsistent, mostly due to differing 18S annotations, although general structure and composition according to pH were coherent. A relatively small number of lineages, mostly putative parasitic protists and fungi, drive most differences between pH classes, with weaker contributions from bacterivores and autotrophs. Overall, soil parasites included a large diversity of alveolates, in particular apicomplexans. Phylogenetic analysis of alveolate lineages demonstrates a large diversity of unknown gregarines, novel perkinsids, coccidians, colpodellids and uncharacterized alveolates. Other novel and/or divergent lineages were revealed across the eukaryote tree of life. Our study provides an in-depth taxonomic evaluation of micro-eukaryotic diversity, and reveals novel lineages and insights into their relationships with environmental variables across soil gradients.


Assuntos
Eucariotos/isolamento & purificação , Solo/química , Solo/parasitologia , Animais , Biodiversidade , Eucariotos/classificação , Eucariotos/genética , Fungos/genética , Fungos/isolamento & purificação , Concentração de Íons de Hidrogênio , Parasitos/genética , Parasitos/isolamento & purificação , Filogenia , RNA Ribossômico 18S/genética , Microbiologia do Solo
7.
J Evol Biol ; 29(3): 551-9, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26663204

RESUMO

A key step in the evolution of multicellular organisms is the formation of cooperative multicellular groups. It has been suggested that predation pressure may promote multicellular group formation in some algae and bacteria, with cells forming groups to lower their chance of being eaten. We use the green alga Chlorella vulgaris and the protist Tetrahymena thermophila to test whether predation pressure can initiate the formation of colonies. We found that: (1) either predators or just predator exoproducts promote colony formation; (2) higher predator densities cause more colonies to form; and (3) colony formation in this system is facultative, with populations returning to being unicellular when the predation pressure is removed. These results provide empirical support for the hypothesis that predation pressure promotes multicellular group formation. The speed of the reversion of populations to unicellularity suggests that this response is due to phenotypic plasticity and not evolutionary change.


Assuntos
Chlorella vulgaris/fisiologia , Tetrahymena thermophila/fisiologia , Animais , Evolução Biológica , Comportamento Predatório
8.
Vet Pathol ; 53(1): 190-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26139838

RESUMO

Machupo virus, the cause of Bolivian hemorrhagic fever, is a highly lethal viral hemorrhagic fever with no Food and Drug Administration-approved vaccines or therapeutics. This study evaluated the guinea pig as a model using the Machupo virus-Chicava strain administered via aerosol challenge. Guinea pigs (Cavia porcellus) were serially sampled to evaluate the temporal progression of infection, gross and histologic lesions, and sequential changes in serum chemistry and hematology. The incubation period was 5 to 12 days, and complete blood counts revealed leukopenia with lymphopenia and thrombocytopenia. Gross pathologic findings included congestion and hemorrhage of the gastrointestinal mucosa and serosa, noncollapsing lungs with fluid exudation, enlarged lymph nodes, and progressive pallor and friability of the liver. Histologic lesions consisted of foci of degeneration and cell death in the haired skin, liver, pancreas, adrenal glands, lymph nodes, tongue, esophagus, salivary glands, renal pelvis, small intestine, and large intestine. Lymphohistiocytic interstitial pneumonia was also present. Inflammation within the central nervous system, interpreted as nonsuppurative encephalitis, was histologically apparent approximately 16 days postexposure and was generally progressive. Macrophages in the tracheobronchial lymph node, on day 5 postexposure, were the first cells to demonstrate visible viral antigen. Viral antigen was detected throughout the lymphoid system by day 9 postexposure, followed by prominent spread within epithelial tissues and then brain. This study provides insight into the course of Machupo virus infection and supports the utility of guinea pigs as an additional animal model for vaccine and therapeutic development.


Assuntos
Arenavirus do Novo Mundo/patogenicidade , Modelos Animais de Doenças , Cobaias , Febre Hemorrágica Americana/patologia , Glândulas Suprarrenais/patologia , Aerossóis , Animais , Epitélio/patologia , Feminino , Febre Hemorrágica Americana/virologia , Humanos , Fígado/patologia , Pulmão/patologia , Linfonodos/patologia , Masculino , Pâncreas/patologia
9.
Vet Pathol ; 52(1): 26-37, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24990481

RESUMO

Machupo virus, the causative agent of Bolivian hemorrhagic fever (BHF), is a highly lethal viral hemorrhagic fever of which little is known and for which no Food and Drug Administration-approved vaccines or therapeutics are available. This study evaluated the cynomolgus macaque as an animal model using the Machupo virus, Chicava strain, via intramuscular and aerosol challenge. The incubation period was 6 to 10 days with initial signs of depression, anorexia, diarrhea, mild fever, and a petechial skin rash. These were often followed by neurologic signs and death within an average of 18 days. Complete blood counts revealed leukopenia as well as marked thrombocytopenia. Serum chemistry values identified a decrease in total protein, marked increases in alanine aminotransferase and aspartate aminotransferase, and moderate increases in alkaline phosphatase. Gross pathology findings included a macular rash extending across the axillary and inguinal regions beginning at approximately 10 days postexposure as well as enlarged lymph nodes and spleen, enlarged and friable liver, and sporadic hemorrhages along the gastrointestinal mucosa and serosa. Histologic lesions consisted of foci of degeneration and necrosis/apoptosis in the haired skin, liver, pancreas, adrenal glands, lymph nodes, tongue, esophagus, salivary glands, stomach, small intestine, and large intestine. Lymphohistiocytic interstitial pneumonia was also present. Inflammation within the central nervous system (nonsuppurative encephalitis) was histologically apparent approximately 16 days postexposure and was generally progressive. This study provides insight into the course of Machupo virus infection in cynomolgus macaques and supports the usefulness of cynomolgus macaques as a viable model of human Machupo virus infection.


Assuntos
Arenavirus do Novo Mundo/fisiologia , Febre Hemorrágica Americana/patologia , Glândulas Suprarrenais/patologia , Aerossóis/administração & dosagem , Animais , Modelos Animais de Doenças , Feminino , Febre Hemorrágica Americana/virologia , Humanos , Injeções Intramusculares , Fígado/patologia , Pulmão/patologia , Linfonodos/patologia , Macaca fascicularis , Masculino , Baço/patologia
10.
Genes Immun ; 15(1): 38-46, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24195963

RESUMO

The Collaborative Cross (CC) is an emerging panel of recombinant inbred (RI) mouse strains. Each strain is genetically distinct but all descended from the same eight inbred founders. In 66 strains from incipient lines of the CC (pre-CC), as well as the 8 CC founders and some of their F1 offspring, we examined subsets of lymphocytes and antigen-presenting cells. We found significant variation among the founders, with even greater diversity in the pre-CC. Genome-wide association using inferred haplotypes detected highly significant loci controlling B-to-T cell ratio, CD8 T-cell numbers, CD11c and CD23 expression. Comparison of overall strain effects in the CC founders with strain effects at QTL in the pre-CC revealed sharp contrasts in the genetic architecture of two traits with significant loci: variation in CD23 can be explained largely by additive genetics at one locus, whereas variation in B-to-T ratio has a more complex etiology. For CD23, we found a strong QTL whose confidence interval contained the CD23 structural gene Fcer2a. Our data on the pre-CC demonstrate the utility of the CC for studying immunophenotypes and the value of integrating founder, CC and F1 data. The extreme immunophenotypes observed could have pleiotropic effects in other CC experiments.


Assuntos
Imunogenética/métodos , Subpopulações de Linfócitos/fisiologia , Camundongos Endogâmicos/imunologia , Locos de Características Quantitativas , Animais , Linfócitos B/fisiologia , Antígeno CD11c/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Variação Genética , Estudo de Associação Genômica Ampla , Haplótipos , Camundongos , Camundongos Endogâmicos/genética , Receptores de IgE/metabolismo , Linfócitos T/fisiologia
11.
Osteoporos Int ; 25(7): 1975-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24839166

RESUMO

UNLABELLED: In bone remodeling, the expression and turnover of the proteoglycans versican and aggrecan are poorly understood. We report changes in adult mouse bone contents of versican and aggrecan associated with both age and treatment with the drug zoledronate. The data may have implications for experimental animal models of osteoporosis and related conditions. INTRODUCTION: Versican and aggrecan are large, aggregating proteoglycans involved in skeletal development, but little is known about their roles in bone remodeling. The purpose of this study was to investigate versican and aggrecan contents in adult mouse bones, and changes in their contents in response to the bisphosphonate zoledronate (ZOL). METHODS: Mice (9 weeks old) were treated with 125 µg/kg ZOL or vehicle for 3 or 15 weeks. Versican and aggrecan were isolated from tibial bones for Western blotting, automated integrated densitometry, and analysis (two-way ANOVA, α = 0.05). RESULTS: In ZOL-treated mouse bones, compared to vehicle, 340 and 60 kDa versican content decreased significantly, and 100 and 60 kDa aggrecan content decreased significantly (drug effect). In 24-week-old mouse bones, compared to 12 weeks, statistically significant decreases were observed in 340, 80, 60, and 11 kDa versican, and in 100, 70, and 40 kDa aggrecan (age effect). There was a statistically significant ZOL-age interaction for 330 kDa aggrecan. CONCLUSION: This is the first study to assess physiological versican and aggrecan adaptations in adult mammalian bone tissue, in the presence and absence of ZOL. We observed large decreases in some versican and aggrecan species from 12 to 24 weeks. We also observed decreases in several versican and aggrecan species in the presence of ZOL. This indicates that bone proteoglycan expression and turnover may be important in bone remodeling.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Difosfonatos/farmacologia , Imidazóis/farmacologia , Tíbia/efeitos dos fármacos , Versicanas/metabolismo , Agrecanas/metabolismo , Envelhecimento/metabolismo , Animais , Remodelação Óssea/efeitos dos fármacos , Feminino , Camundongos Endogâmicos C57BL , Tíbia/metabolismo , Tíbia/fisiologia , Ácido Zoledrônico
12.
Phys Chem Chem Phys ; 16(15): 7108-14, 2014 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-24618928

RESUMO

Both pendant and main chain conjugated MEH-PPV based polymers have been studied at the level of single chains using confocal and widefield fluorescence microscopy techniques. In particular, defocused widefield fluorescence is applied to reveal the extent of energy transfer in these polymers by identifying whether they act as single emitters. For main chain conjugated MEH-PPV, molecular weight and the surrounding matrix play a primary role in determining energy transport processes and whether single emitter behaviour is observed. Surprisingly in polymers with a saturated backbone but containing the same pendant MEH-PPV oligomer on each repeating unit, intra-chain energy transfer to a single emitter is also apparent. The results imply there is chromophore heterogeneity that can facilitate energy funneling to the emitting site. Both main chain conjugated and pendant MEH-PPV polymers exhibit changes in orientation of the emission dipole during a fluorescence trajectory of many seconds, whereas a model MEH-PPV oligomer does not. The results suggest that, in the polymers, the nature of the emitting chromophores can change during the time trajectory.


Assuntos
Transferência de Energia , Microscopia de Fluorescência , Polímeros/química , Compostos de Vinila/química , Microscopia Confocal , Estrutura Molecular
13.
J Clin Pharm Ther ; 39(6): 653-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25200273

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Few studies have evaluated the effect of vancomycin dosing on the health outcomes in geriatric patients. Data are needed to determine whether higher vancomycin dosing strategies are more effective in geriatric patients and/or lead to excessive rates of adverse events. METHODS: This study used a subset of patients aged ≥65 years from a multicentre, retrospective, cohort study of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia. Patients received ≥ 48 h of empiric vancomycin between 1 July 2002 and 30 June 2008. We compared the incidence of nephrotoxicity and in-hospital mortality in patients who received guideline-recommended dosing (at least 15 mg/kg/dose) to patients who received lower dosing. Multivariable generalized mixed-effect models were constructed to determine independent risk factors for nephrotoxicity and in-hospital mortality. RESULTS AND DISCUSSION: Half of the cohort (46% of 92 patients) received guideline-recommended dosing. Empiric use of weight-based dosing did increase the percentage of patients achieving a vancomycin trough ≥ 15 mg/L (57% vs. 42%). Nephrotoxicity occurred in 32% of patients and 26% died during their hospitalization. Guideline-recommended dosing was not associated with significant changes in nephrotoxicity (OR 1·13; 95% CI 0·40-3·19) or in-hospital mortality (OR 1·14; 95% CI 0·41-3·18) in the multivariable analysis. WHAT IS NEW AND CONCLUSION: In this study of geriatric patients, guideline-recommended dosing was not associated with significant changes in nephrotoxicity or mortality. As 40% of the patients who received guideline-recommended dosing failed to achieve a target vancomycin trough of ≥ 15 mg/L, future studies should focus on dosing strategies to increase target attainment rate.


Assuntos
Antibacterianos/administração & dosagem , Bacteriemia/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Peso Corporal , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Mortalidade Hospitalar , Humanos , Nefropatias/epidemiologia , Nefropatias/etiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Análise Multivariada , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/mortalidade , Vancomicina/efeitos adversos , Vancomicina/uso terapêutico
14.
Sci Total Environ ; 858(Pt 2): 159161, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36191696

RESUMO

The presence of SARS-CoV-2 in untreated sewage has been confirmed in many countries but its incidence and infection risk in contaminated waters is poorly understood. The River Thames in the UK receives untreated sewage from 57 Combined Sewer Overflows (CSOs), with many discharging dozens of times per year. This study investigated if such discharges provide a pathway for environmental transmission of SARS-CoV-2. Samples of wastewater, surface water, and sediment collected close to six CSOs on the River Thames were assayed over eight months for SARS-CoV-2 RNA and infectious virus. Bivalves were also sampled as an indicator species of viral bioaccumulation. Sediment and water samples from the Danube and Sava rivers in Serbia, where raw sewage is also discharged in high volumes, were assayed as a positive control. No evidence of SARS-CoV-2 RNA or infectious virus was found in UK samples, in contrast to RNA positive samples from Serbia. Furthermore, this study shows that infectious SARS-CoV-2 inoculum is stable in Thames water and sediment for <3 days, while SARS-CoV-2 RNA is detectable for at least seven days. This indicates that dilution of wastewater likely limits environmental transmission, and that detection of viral RNA alone is not an indication of pathogen spillover.


Assuntos
COVID-19 , Esgotos , Humanos , Águas Residuárias , SARS-CoV-2 , RNA Viral , Monitoramento Ambiental , COVID-19/epidemiologia , Água
15.
Multimed Tools Appl ; 81(18): 26143-26161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35368859

RESUMO

Red lesion identification at its early stage is very essential for the treatment of diabetic retinopathy to prevent loss of vision. This work proposes a red lesion detection algorithm that uses Hexagonal pattern-based features with two-level segmentation that can detect hemorrhage and microaneurysms in the fundus image. The proposed scheme initially pre-processes the fundus image followed by a two-level segmentation. The level 1 segmentation eliminates the background whereas the level 2 segmentation eliminates the blood vessels that introduce more false positives. A hexagonal pattern-based feature is extracted from the red lesion candidates which can highly differentiate the lesion from non-lesion regions. The hexagonal pattern features are then trained using the recurrent neural network and are classified to eliminate the false negatives. For the evaluation of the proposed red lesion algorithm, the datasets namely ROC challenge, e-ophtha, DiaretDB1, and Messidor are used with the metrics such as Accuracy, Recall, Precision, F1 score, Specificity, and AUC. The scheme provides an average Accuracy, Recall (Sensitivity), Precision, F1 score, Specificity, and AUC of 95.48%, 84.54%, 97.3%, 90.47%, 86.81% and 93.43% respectively.

16.
Hum Reprod ; 24(6): 1501-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19279040

RESUMO

BACKGROUND: Although previous epidemiological studies have shown that women with endometriosis are more likely to be thinner and underweight, it is currently not clear whether this is a true characteristic of women who develop endometriosis or a consequence of their disease and its symptoms. The aim of this study was to investigate the relationship between endometriosis and relative weight in childhood and adolescence, prior to diagnosis. METHODS: This case-control study included 268 Australian women with surgically confirmed moderate to severe endometriosis (cases) and 244 women without endometriosis (controls). Relative weight at ages 10 and 16 years, as recalled and classified ('underweight', 'average weight' and 'overweight') separately by the women themselves and their mothers, was analyzed. RESULTS: Women who reported being overweight at 10 years had an increased risk of endometriosis (OR 2.8; 95% CI 1.1-7.5). Mothers' reports and concordant responses among mother-daughter pairs were consistent with this association. There was no clear evidence of an association between relative weight at 16 years and risk of endometriosis. CONCLUSIONS: These data suggest that being overweight during late childhood is associated with the development of endometriosis; however, the results warrant confirmation in larger study populations.


Assuntos
Peso Corporal , Endometriose/epidemiologia , Sobrepeso/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Austrália/epidemiologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença , Adulto Jovem
17.
Science ; 215(4537): 1264-5, 1982 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-17757544

RESUMO

7-Hydroxy-6,7-dihydro-5H-pyrolizine-1-carboxaldehyde is the major volatile component of the scent organs in males of two species of Creatonotos (Lepidoptera, Arctiidae). The biosynthesis of this presumed pheromone depends on the presence of pyrrolizidine alkaloids in plants that are ingested by the larvae. In addition, these secondary plant substances control the morphogenesis of the scent organs. This morphogenetic effect of an alkaloid has not been observed previously.

18.
Science ; 269(5224): 671-4, 1995 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-7624796

RESUMO

An artificial receptor has been designed to bind creatinine with a color change (chromogenic response) caused by proton transfer from one end of the receptor to the other. The receptor was synthesized and found to extract creatinine from water into chlorocarbon solvents. The color change in the organic layer is specific for creatinine relative to other organic solutes, and it is selective for creatinine relative to sodium, potassium, and ammonium ions. The chromogenic mechanism is revealed by x-ray crystal structures of creatinine, the free receptor, and the complex, showing "induced fit" binding resulting from electronic complementarity between host and guest.


Assuntos
Acridinas/síntese química , Compostos Cromogênicos/síntese química , Creatinina/análise , Naftiridinas/síntese química , Acridinas/química , Sítios de Ligação , Compostos Cromogênicos/química , Creatinina/sangue , Creatinina/química , Cristalização , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Hidrogênio/química , Ligação de Hidrogênio , Naftiridinas/química , Oxigênio/química , Prótons
19.
Science ; 189(4203): 632-4, 1975 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-17838752

RESUMO

Thermistor chain measurements of internal wave motions below the thermocline in the western North Atlantic have been spectrally decomposed in vertical-horizontal wave number space. The measured two-dimensional spectrum exhibits a systematic deviation from the corresponding Garrett and Munk model for internal wave spectra.

20.
Appl Radiat Isot ; 151: 317-330, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31376719

RESUMO

A new radio-HPLC detection system for measuring radioactivity in plasma samples during Positron Emission Tomography [PET] studies was developed. It is based on detecting both the positron and one of the annihilation photons. The system focused on improving the measurement of radioactivity concentrations on an unmetabolized positron emitting a radiopharmaceutical [PER] in the presence of its radioactive metabolites, all containing the same positron emitter. This paper presents a new detection configuration that improves the minimal detectible activity (MDA), simplify the measuring systems and reduces the error caused by the metabolites. The detector is based on a plastic scintillator and a BGO scintillation crystal, that produces different light output spectra for signal and noise events. By summing the positron and the annihilated photon light outputs, different spectra are obtained for the metabolite and for the parent compound tracer and for tracer marked by different positron emitting isotopes. This new detection system can improve quantitative analysis of plasma samples. The spectrum change provides up to a three-fold improvement in sensitivity compared to the currently used detection systems that measure only the annihilation coincidence events. Results showed that for 11C the MDA was improved by approximately 520%. Furthermore, it provides the additional advantage of reliability by providing a method for separating the signal and noise readings from the gross detector readout. Accurate reconstruction algorithm of the signal was achieved over a wide measuring range even when the signal was only 5% of the gross measurement.


Assuntos
Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/sangue , Algoritmos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Reprodutibilidade dos Testes
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