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1.
Phlebology ; : 2683555231212302, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37934910

RESUMO

The core content for a medical specialty outlines the scope of the discipline as well as the categories of knowledge considered essential to practice in the field. It provides a template for the development of curricula for medical school, graduate, and postgraduate education, as well as for creating certification standards. Venous and Lymphatic Medicine (VLM) is a specialty that has benefitted from contributions from specialists from several medical disciplines. Optimally, the societies, boards, and residency review committees representing these disciplines would uniformly recognize the scope of VLM to develop education and assessment standards to allow training and identification of qualified practitioners. In order to inform the standard setting bodies and other stakeholders of the current scope of VLM, a task force of VLM experts from cardiology, dermatology, emergency medicine, general surgery, interventional radiology, vascular medicine, and vascular surgery was formed to revise a 2014 consensus document defining the core content of the specialty of VLM.

2.
Commun Biol ; 6(1): 1203, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007534

RESUMO

There are nearly 65 million people with chronic heart failure (CHF) globally, with no treatment directed at the pathologic cause of the disease, the loss of functioning cardiomyocytes. We have an allogeneic cardiac patch comprised of cardiomyocytes and human fibroblasts on a bioresorbable matrix. This patch increases blood flow to the damaged heart and improves left ventricular (LV) function in an immune competent rat model of ischemic CHF. After 6 months of treatment in an immune competent Yucatan mini swine ischemic CHF model, this patch restores LV contractility without constrictive physiology, partially reversing maladaptive LV and right ventricular remodeling, increases exercise tolerance, without inducing any cardiac arrhythmias or a change in myocardial oxygen consumption. Digital spatial profiling in mice with patch placement 3 weeks after a myocardial infarction shows that the patch induces a CD45pos immune cell response that results in an infiltration of dendritic cells and macrophages with high expression of macrophages polarization to the anti-inflammatory reparative M2 phenotype. Leveraging the host native immune system allows for the potential use of immunomodulatory therapies for treatment of chronic inflammatory diseases not limited to ischemic CHF.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Ratos , Camundongos , Humanos , Animais , Suínos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , Função Ventricular Esquerda , Macrófagos/metabolismo
3.
Phys Rev Lett ; 128(1): 011801, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061499

RESUMO

Dark matter with Planck-scale mass (≃10^{19} GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark matter was performed with a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate signals were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between 8.3×10^{6} and 1.2×10^{19} GeV/c^{2}, and ^{40}Ar-scattering cross sections between 1.0×10^{-23} and 2.4×10^{-18} cm^{2}. These results are interpreted as constraints on composite dark matter models with two different nucleon-to-nuclear cross section scalings.

4.
Eur Phys J C Part Fields ; 81(9): 823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720726

RESUMO

The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. The largest background comes from 39 Ar beta decays and is suppressed using pulse-shape discrimination (PSD). We use two types of PSD estimator: the prompt-fraction, which considers the fraction of the scintillation signal in a narrow and a wide time window around the event peak, and the log-likelihood-ratio, which compares the observed photon arrival times to a signal and a background model. We furthermore use two algorithms to determine the number of photons detected at a given time: (1) simply dividing the charge of each PMT pulse by the mean single-photoelectron charge, and (2) a likelihood analysis that considers the probability to detect a certain number of photons at a given time, based on a model for the scintillation pulse shape and for afterpulsing in the light detectors. The prompt-fraction performs approximately as well as the log-likelihood-ratio PSD algorithm if the photon detection times are not biased by detector effects. We explain this result using a model for the information carried by scintillation photons as a function of the time when they are detected.

5.
Phys Rev Lett ; 124(23): 232502, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603173

RESUMO

We report on a comparison between the theoretically predicted and experimentally measured spectra of the first-forbidden nonunique ß-decay transition ^{137}Xe(7/2^{-})→^{137}Cs(7/2^{+}). The experimental data were acquired by the EXO-200 experiment during a deployment of an AmBe neutron source. The ultralow background environment of EXO-200, together with dedicated source deployment and analysis procedures, allowed for collection of a pure sample of the decays, with an estimated signal to background ratio of more than 99 to 1 in the energy range from 1075 to 4175 keV. In addition to providing a rare and accurate measurement of the first-forbidden nonunique ß-decay shape, this work constitutes a novel test of the calculated electron spectral shapes in the context of the reactor antineutrino anomaly and spectral bump.

6.
Phys Rev Lett ; 123(16): 161802, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31702371

RESUMO

A search for neutrinoless double-ß decay (0νßß) in ^{136}Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between 0νßß and background events. Relative to previous analyses, the signal detection efficiency has been raised from 80.8% to 96.4±3.0%, and the energy resolution of the detector at the Q value of ^{136}Xe 0νßß has been improved from σ/E=1.23% to 1.15±0.02% with the upgraded detector. Accounting for the new data, the median 90% confidence level 0νßß half-life sensitivity for this analysis is 5.0×10^{25} yr with a total ^{136}Xe exposure of 234.1 kg yr. No statistically significant evidence for 0νßß is observed, leading to a lower limit on the 0νßß half-life of 3.5×10^{25} yr at the 90% confidence level.

7.
Phys Rev Lett ; 120(7): 072701, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29542972

RESUMO

Results from a search for neutrinoless double-beta decay (0νßß) of ^{136}Xe are presented using the first year of data taken with the upgraded EXO-200 detector. Relative to previous searches by EXO-200, the energy resolution of the detector has been improved to σ/E=1.23%, the electric field in the drift region has been raised by 50%, and a system to suppress radon in the volume between the cryostat and lead shielding has been implemented. In addition, analysis techniques that improve topological discrimination between 0νßß and background events have been developed. Incorporating these hardware and analysis improvements, the median 90% confidence level 0νßß half-life sensitivity after combining with the full data set acquired before the upgrade has increased twofold to 3.7×10^{25} yr. No statistically significant evidence for 0νßß is observed, leading to a lower limit on the 0νßß half-life of 1.8×10^{25} yr at the 90% confidence level.

8.
BMJ Open Diabetes Res Care ; 3(1): e000124, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26464803

RESUMO

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is associated with high levels of disability and mortality. Regular exercise prevents premature disability and mortality, but people with T2DM are generally sedentary for reasons that are not fully established. We previously observed that premenopausal women with T2DM report greater effort during exercise than their counterparts without diabetes, as measured by the Rating of Perceived Exertion (RPE) scale. We hypothesized that RPE is greater in older women with T2DM versus no T2DM. RESEARCH DESIGN AND METHODS: We enrolled overweight, sedentary women aged 50-75 years with (n=26) or without T2DM (n=28). Participants performed submaximal cycle ergometer exercise at 30 W and 35% of individually-measured peak oxygen consumption (35% VO2peak). We assessed exercise effort by RPE (self-report) and plasma lactate concentration. RESULTS: VO2peak was lower in T2DM versus controls (p=0.003). RPE was not significantly greater in T2DM versus controls (30 W: Control, 10.4±3.2, T2DM, 11.7±2.3, p=0.08; 35% VO2peak: Control, 11.1±0.5, T2DM, 12.1±0.5, p=0.21). However, lactate was greater in T2DM versus controls (p=0.004 at 30 W; p<0.05 at 35% VO2peak). Greater RPE was associated with higher lactate, higher heart rate, and a hypertension diagnosis (p<0.05 at 30 W and 35% VO2peak). CONCLUSIONS: Taken together, physiological measures of exercise effort were greater in older women with T2DM than controls. Exercise effort is a modifiable and thereby targetable end point. In order to facilitate regular exercise, methods to reduce exercise effort in T2DM should be sought. TRIAL NUMBER: NCT00785005.

10.
Rev Sci Instrum ; 85(9): 095114, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25273779

RESUMO

We describe a system to transport and identify barium ions produced in liquid xenon, as part of R&D towards the second phase of a double beta decay experiment, nEXO. The goal is to identify the Ba ion resulting from an extremely rare nuclear decay of the isotope (136)Xe, hence providing a confirmation of the occurrence of the decay. This is achieved through Resonance Ionization Spectroscopy (RIS). In the test setup described here, Ba ions can be produced in liquid xenon or vacuum and collected on a clean substrate. This substrate is then removed to an analysis chamber under vacuum, where laser-induced thermal desorption and RIS are used with time-of-flight mass spectroscopy for positive identification of the barium decay product.

12.
Exp Neurol ; 232(1): 90-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21867704

RESUMO

Nitro-oleic acid (9- and 10-nitro-octadeca-9-enoic acid, OA-NO(2)) is an electrophilic fatty acid nitroalkene derivative that modulates gene transcription and protein function via post-translational protein modification. Nitro-fatty acids are generated from unsaturated fatty acids by oxidative inflammatory reactions and acidic conditions in the presence of nitric oxide or nitrite. Nitroalkenes react with nucleophiles such as cysteine and histidine in a variety of susceptible proteins including transient receptor potential (TRP) channels in sensory neurons of the dorsal root and nodose ganglia. The present study revealed that OA-NO(2) activates TRP channels on afferent nerve terminals in the urinary bladder and thereby increases bladder activity. The TRPV1 agonist capsaicin (CAPS, 1 µM) and the TRPA1 agonist allyl isothiocyanate (AITC, 30 µM), elicited excitatory effects in bladder strips, increasing basal tone and amplitude of phasic bladder contractions (PBC). OA-NO(2) mimicked these effects in a concentration-dependent manner (1 µM-33 µM). The TRPA1 antagonist HC3-030031 (HC3, 30 µM) and the TRPV1 antagonist diaryl piperazine analog (DPA, 1 µM), reduced the effect of OA-NO(2) on phasic contraction amplitude and baseline tone. However, the non-selective TRP channel blocker, ruthenium red (30 µM) was a more effective inhibitor, reducing the effects of OA-NO(2) on basal tone by 75% and the effects on phasic amplitude by 85%. In bladder strips from CAPS-treated rats, the effect of OA-NO(2) on phasic contraction amplitude was reduced by 65% and the effect on basal tone was reduced by 60%. Pretreatment of bladder strips with a combination of neurokinin receptor antagonists (NK1 selective antagonist, CP 96345; NK2 selective antagonist, MEN 10,376; NK3 selective antagonist, SB 234,375, 1 µM each) reduced the effect of OA-NO(2) on basal tone, but not phasic contraction amplitude. These results indicate that nitroalkene fatty acid derivatives can activate TRP channels on CAPS-sensitive afferent nerve terminals, leading to increased bladder contractile activity. Nitrated fatty acids produced endogenously by the combination of fatty acids and oxides of nitrogen released from the urothelium and/or afferent nerves may play a role in modulating bladder activity.


Assuntos
Ácido Oleico/farmacologia , Células Receptoras Sensoriais/efeitos dos fármacos , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/antagonistas & inibidores , Bexiga Urinária/fisiologia , Animais , Capsaicina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Ratos , Ratos Sprague-Dawley , Fármacos do Sistema Sensorial/farmacologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/inervação
13.
Appl Environ Microbiol ; 74(4): 987-93, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18156324

RESUMO

Fibrobacter is a highly cellulolytic genus commonly found in the rumen of ruminant animals and cecum of monogastric animals. In this study, suppression subtractive hybridization was used to identify the genes present in Fibrobacter succinogenes S85 but absent from F. intestinalis DR7. A total of 1,082 subtractive clones were picked, plasmids were purified, and inserts were sequenced, and the clones lacking homology to F. intestinalis were confirmed by Southern hybridization. By comparison of the sequences of the clones to one another and to those of the F. succinogenes genome, 802 sequences or 955 putative genes, comprising approximately 409 kb of F. succinogenes genomic DNA, were identified that lack similarity to those of F. intestinalis chromosomal DNA. The functional groups of genes, including those involved in cell envelope structure and function, energy metabolism, and transport and binding, had the largest number of genes specific to F. succinogenes. Low-stringency Southern hybridization showed that at least 37 glycoside hydrolases are shared by both species. A cluster of genes responsible for heme, porphyrin, and cobalamin biosynthesis in F. succinogenes S85 was either missing from or not functional in F. intestinalis DR7, which explains the requirement of vitamin B12 for the growth of the F. intestinalis species. Two gene clusters encoding NADH-ubiquinone oxidoreductase subunits probably shared by Fibrobacter genera appear to have an important role in energy metabolism.


Assuntos
Fibrobacter/genética , Genes Bacterianos/genética , Genoma Bacteriano/genética , Southern Blotting , Biologia Computacional , Hibridização de Ácido Nucleico , Análise de Sequência de DNA , Especificidade da Espécie
15.
J Anim Sci ; 84(6): 1439-53, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16699101

RESUMO

The objectives were to determine if strategic supplementation of range cows with a long-acting (6 mo), trace mineral, reticulorumen bolus containing Cu, Se, and Co would: (1) increase cow BCS and BW, and calf birth, weaning, and postweaning weights, or weight per day of age (WDA); (2) increase liver concentrations of Cu or Zn in cows, or blood Se, Cu, or Zn concentrations in cows and calves; and (3) vary by cow breed for any of these response variables. There were 192 control and 144 bolused Composite cows (C; 25% Hereford, Angus, Gelbevieh, and Senepol or Barzona); 236 control and 158 bolused Hereford (H) cows; and 208 control and 149 bolused Brahman cross (B) cows used in a 3-yr experiment. Cows were weighed and scored for body condition in January, May, and September, and all bolused cows received boluses in January. Each year, from among the 3 breed groups a subset of 15 control and 15 bolused cows (n = 90) had samples obtained in January and May for liver Cu and Zn, blood Se, and serum Cu and Zn. As for cows, blood and serum from the calves of these cows were sampled each year in May and September for Cu, Se, and Zn. There was a significant breed x year x treatment interaction (P = 0.001) for cow weight loss from January to May. Calf WDA, weaning, and postweaning weights did not differ (P > 0.40) between bolused and control cows, but there was a significant (P = 0.022) breed x year x treatment interaction for birth weight. Liver Cu was deficient (< 75 ppm; P < 0.001) in control cows and adequate (< 75 to 90 ppm) for bolused cows. Liver Cu differed by year (P < 0.001). Blood Se was adequate (< 0.1 ppm) for all cows except in January 2001 and 2002. There was no difference (P > 0.50) in blood Se between treatment groups in January, but bolused cows had greater (P < 0.01) blood Se in May. Breed differences for blood Se concentrations existed for bolused cows, with B having greater (P < 0.05) blood Se than either C or H cows. Breed differences also existed for control cows, with H having less blood Se (P < 0.04) than B or C cows. Calves from bolused cows had greater blood Se than calves from control cows (P = 0.01). Supplementation via a long-acting trace mineral bolus was successful in increasing liver Cu in cows and blood Se in cows and calves, but the responses varied by year. Bolus administration had variable effects on BW change in early lactation, depending on breed and year, which may indicate the need for breed- and year-specific supplementation programs.


Assuntos
Criação de Animais Domésticos , Bovinos/fisiologia , Oligoelementos/administração & dosagem , Animais , Peso Corporal , Química Farmacêutica , Cobre/análise , Cobre/metabolismo , Feminino , Fígado/química , Fígado/metabolismo , Selênio/sangue , Fatores de Tempo , Zinco/análise , Zinco/metabolismo
16.
Proc Natl Acad Sci U S A ; 102(50): 18147-52, 2005 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-16330755

RESUMO

Saturated thalassic brines are among the most physically demanding habitats on Earth: few microbes survive in them. Salinibacter ruber is among these organisms and has been found repeatedly in significant numbers in climax saltern crystallizer communities. The phenotype of this bacterium is remarkably similar to that of the hyperhalophilic Archaea (Haloarchaea). The genome sequence suggests that this resemblance has arisen through convergence at the physiological level (different genes producing similar overall phenotype) and the molecular level (independent mutations yielding similar sequences or structures). Several genes and gene clusters also derive by lateral transfer from (or may have been laterally transferred to) haloarchaea. S. ruber encodes four rhodopsins. One resembles bacterial proteorhodopsins and three are of the haloarchaeal type, previously uncharacterized in a bacterial genome. The impact of these modular adaptive elements on the cell biology and ecology of S. ruber is substantial, affecting salt adaptation, bioenergetics, and photobiology.


Assuntos
Archaea/genética , Bacteroidetes/genética , Evolução Molecular , Transferência Genética Horizontal/genética , Genoma Bacteriano/genética , Filogenia , Rodopsinas Microbianas/genética , Adaptação Fisiológica/genética , Bacteroidetes/enzimologia , Composição de Bases , Sequência de Bases , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA
17.
Ann Hum Genet ; 68(Pt 5): 498-508, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15469426

RESUMO

We use data on lymphoma in families of Hodgkin lymphoma (HL) cases from the Swedish Family Cancer Database (Hemminki et al. 2001) to illustrate survival methods for detecting familial aggregation in first degree relatives of case probands compared to first degree relatives of control probands, from registries that permit sampling of all cases. Because more than one case may occur in a given family, the first degree relatives of case probands are not necessarily independent, and we present procedures that allow for such dependence. A bootstrap procedure also accommodates matching of case and control probands by resampling the matching clusters, defined as the combined set of all first degree relatives of the matched case and control probands. Regarding families as independent sampling units leads to inferences based on "sandwich variance estimators" and accounts for dependencies from having more than one proband in a family, but not for matching. We compare these methods in analysis of familial aggregation of HL and also present simulations to compare survival analyses with analyses of binary outcome data.


Assuntos
Predisposição Genética para Doença , Doença de Hodgkin/genética , Linfoma não Hodgkin/genética , Sistema de Registros/estatística & dados numéricos , Adulto , Idoso , Estudos de Casos e Controles , Bases de Dados Genéticas , Feminino , Doença de Hodgkin/epidemiologia , Humanos , Linfoma não Hodgkin/epidemiologia , Masculino , Pessoa de Meia-Idade , Linhagem , Análise de Sobrevida , Suécia/epidemiologia
18.
Science ; 302(5652): 1967-9, 2003 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-14671304

RESUMO

The complete genome sequence of Geobacter sulfurreducens, a delta-proteobacterium, reveals unsuspected capabilities, including evidence of aerobic metabolism, one-carbon and complex carbon metabolism, motility, and chemotactic behavior. These characteristics, coupled with the possession of many two-component sensors and many c-type cytochromes, reveal an ability to create alternative, redundant, electron transport networks and offer insights into the process of metal ion reduction in subsurface environments. As well as playing roles in the global cycling of metals and carbon, this organism clearly has the potential for use in bioremediation of radioactive metals and in the generation of electricity.


Assuntos
Genoma Bacteriano , Geobacter/genética , Geobacter/metabolismo , Metais/metabolismo , Acetatos/metabolismo , Acetilcoenzima A/metabolismo , Aerobiose , Anaerobiose , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbono/metabolismo , Quimiotaxia , Cromossomos Bacterianos/genética , Citocromos c/genética , Citocromos c/metabolismo , Transporte de Elétrons , Metabolismo Energético , Genes Bacterianos , Genes Reguladores , Geobacter/fisiologia , Hidrogênio/metabolismo , Movimento , Fases de Leitura Aberta , Oxirredução , Filogenia
19.
Science ; 299(5615): 2071-4, 2003 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-12663927

RESUMO

The complete genome sequence of Enterococcus faecalis V583, a vancomycin-resistant clinical isolate, revealed that more than a quarter of the genome consists of probable mobile or foreign DNA. One of the predicted mobile elements is a previously unknown vanB vancomycin-resistance conjugative transposon. Three plasmids were identified, including two pheromone-sensing conjugative plasmids, one encoding a previously undescribed pheromone inhibitor. The apparent propensity for the incorporation of mobile elements probably contributed to the rapid acquisition and dissemination of drug resistance in the enterococci.


Assuntos
Evolução Biológica , Enterococcus faecalis/genética , Genoma Bacteriano , Sequências Repetitivas Dispersas , Análise de Sequência de DNA , Resistência a Vancomicina/genética , Adesinas Bacterianas/genética , Aderência Bacteriana , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Cromossomos Bacterianos/genética , Conjugação Genética , Sequência Conservada , Elementos de DNA Transponíveis , Sistema Digestório/microbiologia , Farmacorresistência Bacteriana Múltipla , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/patogenicidade , Enterococcus faecalis/fisiologia , Transferência Genética Horizontal , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Lisogenia , Fases de Leitura Aberta , Estresse Oxidativo , Plasmídeos , Sintenia , Virulência/genética , Fatores de Virulência/genética
20.
Environ Microbiol ; 4(12): 799-808, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12534463

RESUMO

Pseudomonas putida is a metabolically versatile saprophytic soil bacterium that has been certified as a biosafety host for the cloning of foreign genes. The bacterium also has considerable potential for biotechnological applications. Sequence analysis of the 6.18 Mb genome of strain KT2440 reveals diverse transport and metabolic systems. Although there is a high level of genome conservation with the pathogenic Pseudomonad Pseudomonas aeruginosa (85% of the predicted coding regions are shared), key virulence factors including exotoxin A and type III secretion systems are absent. Analysis of the genome gives insight into the non-pathogenic nature of P. putida and points to potential new applications in agriculture, biocatalysis, bioremediation and bioplastic production.


Assuntos
Metabolismo Energético , Genoma Bacteriano , Fases de Leitura Aberta/genética , Pseudomonas putida/genética , Proteínas de Bactérias/genética , Sequência de Bases , Genes Bacterianos/genética , Dados de Sequência Molecular , Filogenia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pseudomonas putida/metabolismo
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