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1.
Nature ; 578(7793): 60-65, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31996851

RESUMO

Precision spectroscopy of atomic systems1 is an invaluable tool for the study of fundamental interactions and symmetries2. Recently, highly charged ions have been proposed to enable sensitive tests of physics beyond the standard model2-5 and the realization of high-accuracy atomic clocks3,5, owing to their high sensitivity to fundamental physics and insensitivity to external perturbations, which result from the high binding energies of their outer electrons. However, the implementation of these ideas has been hindered by the low spectroscopic accuracies (of the order of parts per million) achieved so far6-8. Here we cool trapped, highly charged argon ions to the lowest temperature reported so far, and study them using coherent laser spectroscopy, achieving an increase in precision of eight orders of magnitude. We use quantum logic spectroscopy9,10 to probe the forbidden optical transition in 40Ar13+ at a wavelength of 441 nanometres and measure its excited-state lifetime and g-factor. Our work unlocks the potential of highly charged ions as ubiquitous atomic systems for use in quantum information processing, as frequency standards and in highly sensitive tests of fundamental physics, such as searches for dark-matter candidates11 or violations of fundamental symmetries2.

2.
Phys Rev Lett ; 131(2): 020601, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505962

RESUMO

We present a new method for coherent control of trapped ion qubits in separate interaction regions of a multizone trap by simultaneously applying an electric field and a spin-dependent gradient. Both the phase and amplitude of the effective single-qubit rotation depend on the electric field, which can be localized to each zone. We demonstrate this interaction on a single ion using both laser-based and magnetic-field gradients in a surface-electrode ion trap, and measure the localization of the electric field.

3.
Ir Med J ; 116(No.1): 3, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36917018

RESUMO

BowelScreen paused activity in March 2020 to prioritise the response to the COVID-19 pandemic. The aim of this study was to examine the impact of this delay. Cases affected by the pause and subsequently completed were compared to the same period in 2019. Endoscopy and histology data were obtained from the BowelScreen database and patient records. One-hundred and seven colonoscopies were performed during the study period. This compared with 224 colonoscopies during the same period in 2019. Median lead time to colonoscopy in 2020 was 74 days compared to 34 days in 2019. Adenoma detection rate was 59% for both periods. Advanced adenoma and cancer detection rates were similar in both periods. While there was a marked reduction in activity and significant delays for BowelScreen patients during the first wave of the COVID-19 pandemic, this does not appear to have impacted on clinical outcomes for patients who attended for screening colonoscopy.


Assuntos
Adenoma , COVID-19 , Neoplasias Colorretais , Humanos , SARS-CoV-2 , Pandemias/prevenção & controle , Detecção Precoce de Câncer , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Colonoscopia , Programas de Rastreamento , Adenoma/diagnóstico , Adenoma/epidemiologia
4.
Emerg Infect Dis ; 28(4): 888-890, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35318934

RESUMO

Leishmaniases are neglected tropical diseases of humans and animals. We detected Leishmania infantum in 3 mixed-breed dogs in Zambia that had no travel history outside the country. Our findings suggest presence of and probable emergence of leishmaniasis in Zambia, indicating the need for physicians and veterinarians to consider the disease during diagnosis.


Assuntos
Leishmania infantum , Leishmaniose , Animais , Cães , Leishmaniose/veterinária , Doenças Negligenciadas , Probabilidade , Zâmbia/epidemiologia
5.
Molecules ; 27(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36014540

RESUMO

Nitroxyl shows a unique biological profile compared to the gasotransmitters nitric oxide and hydrogen sulfide. Nitroxyl reacts with thiols as an electrophile, and this redox chemistry mediates much of its biological chemistry. This reactivity necessitates the use of donors to study nitroxyl's chemistry and biology. The preparation and evaluation of a small library of new redox-triggered nitroxyl sources is described. The condensation of sulfonyl chlorides and properly substituted O-benzyl hydroxylamines produced O-benzyl-substituted sulfohydroxamic acid derivatives with a 27-79% yield and with good purity. These compounds were designed to produce nitroxyl through a 1, 6 elimination upon oxidation or reduction via a Piloty's acid derivative. Gas chromatographic headspace analysis of nitrous oxide, the dimerization and dehydration product of nitroxyl, provides evidence for nitroxyl formation. The reduction of derivatives containing nitro and azide groups generated nitrous oxide with a 25-92% yield, providing evidence of nitroxyl formation. The oxidation of a boronate-containing derivative produced nitrous oxide with a 23% yield. These results support the proposed mechanism of nitroxyl formation upon reduction/oxidation via a 1, 6 elimination and Piloty's acid. These compounds hold promise as tools for understanding nitroxyl's role in redox biology.


Assuntos
Sulfeto de Hidrogênio , Óxido Nitroso , Sulfeto de Hidrogênio/química , Óxido Nítrico , Óxidos de Nitrogênio/química , Oxirredução
6.
Bioorg Med Chem Lett ; 48: 128245, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34242759

RESUMO

Nitroaromatic antibiotics are used to treat a variety of bacterial and parasitic infections. These prodrugs require reductive bioactivation for activity, which provides a pathway for the release of nitrogen oxide species such as nitric oxide, nitrite, and/or nitroxyl. Using sodium borohydride and 2-aminoethanol as model reductants, this work examines release of nitrogen oxide species from various nitroaromatic compounds through several characterization methods. Specifically, 4- and 5-nitroimidazoles reproducibly generate higher amounts of nitrite (not nitric oxide or nitroxyl) than 2-nitroimidazoles during the reaction of model hydride donors or thiols. Mass spectrometric analysis shows clean formation of products resulting from nucleophile addition and nitro group loss. 2-Nitrofurans generate nitrite upon addition of sodium borohydride or 2-aminoethanethiol, but these complex reactions do not produce clean organic products. A mechanism that includes nucleophile addition to the carbon ßto the nitro group to generate a nitronate anion followed by protonation and nitrous acid elimination explains the observed products and labeling studies. These systematic studies give a better understanding of the release mechanisms of nitrogen oxide species from these compounds allowing for the design of more efficient therapeutics.


Assuntos
Antibacterianos/química , Boroidretos/química , Nitritos/química , Nitrocompostos/química , Compostos de Sulfidrila/química , Estrutura Molecular
7.
AIDS Behav ; 25(11): 3770-3781, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33733310

RESUMO

Men who have sex with men (MSM) account for more than two thirds of new HIV diagnoses annually. Sexual behavior that increases risk for onward transmission of HIV is associated with both alcohol and cannabis use. However, little is known about the influence of cannabis and alcohol co-use on engagement in condomless anal sex (CAS). The current study explored daily associations between substance use and CAS among HIV-positive MSM using a 42-day timeline followback interview (N = 101). Generalized estimating equation (GEE) logistic regression models were used to examine the association between cannabis and alcohol co-use and CAS at the sexual event while controlling for study site, condition, adherence to antiretroviral therapy, sex-related alcohol expectancies, and partner type. Participants provided data for 1052 sexual activity days, 60.7% of which involved CAS. Of 638 CAS days, 9.1% involved no substances, 72.0% involved either cannabis or alcohol use, and 18.9% involved cannabis and alcohol co-use. Results indicated that the odds of engaging in CAS were higher for sexual events in which cannabis and alcohol co-use occurred (aOR 2.98; 95% CI 1.27, 6.97) compared to events in which no substance use occurred (p = 0.012), but this relationship was no longer significant when cannabis and alcohol co-use was compared to single substance use (aOR 1.57; 95% CI 0.85, 2.90; p = 0.15). Future research should identify specific substance use (e.g., quantity) and partner characteristics (e.g., level of intoxication) that may uniquely influence the relationship between cannabis and alcohol co-use and condomless sex.


Assuntos
Cannabis , Infecções por HIV , Minorias Sexuais e de Gênero , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Assunção de Riscos , Comportamento Sexual , Parceiros Sexuais , Sexo sem Proteção
8.
Arch Virol ; 166(3): 915-919, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33475831

RESUMO

Tick-borne pathogens are an emerging public health threat worldwide. However, information on tick-borne viruses is scanty in sub-Saharan Africa. Here, by RT-PCR, 363 ticks (Amblyomma, Hyalomma and Rhipicephalus) in the Namwala and Livingstone districts of Zambia were screened for tick-borne phleboviruses (TBPVs). TBPVs (L gene) were detected in 19 (5.2%) Rhipicephalus ticks in Namwala. All the detected TBPVs were Shibuyunji viruses. Phylogenetically, they were closely related to American dog tick phlebovirus. This study highlights the possible role of Rhipicephalus ticks as the main host of Shibuyunji virus and suggests that these viruses may be present outside the area where they were initially discovered.


Assuntos
Amblyomma/virologia , Febre por Flebótomos/epidemiologia , Phlebovirus/isolamento & purificação , Rhipicephalus/virologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Variação Genética/genética , Febre por Flebótomos/transmissão , Febre por Flebótomos/virologia , Phlebovirus/genética , Filogenia , Prevalência , Análise de Sequência de DNA , Doenças Transmitidas por Carrapatos/virologia , Zâmbia/epidemiologia
9.
J Hum Nutr Diet ; 34(2): 345-355, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32869430

RESUMO

BACKGROUND: Low muscularity and malnutrition at intensive care unit (ICU) admission have been associated with negative clinical outcomes. There are limited data available evaluating the validity of bedside techniques to measure muscle mass in critically ill adults. We aimed to compare bedside methods for muscle mass assessment [bioimpedance spectroscopy (BIS), arm anthropometry and subjective physical assessment] against reference technology [computed tomography (CT)] at ICU admission. METHODS: Adults who had CT scanning at the third lumbar area <72 h after ICU admission were prospectively recruited. Bedside methods were performed within 48 h of the CT scan. Pearson's correlation compared CT muscle area with BIS-derived fat-free mass (FFM) (kg) and FFM-Chamney (kg) (adjusted for overhydration), mid-upper arm circumference (cm) and mid-arm muscle circumference (cm). Depleted muscle stores were determined using published thresholds for each method. Cohen's kappa (κ) was used to evaluate the agreement between bedside and CT assessment of muscularity status (normal or low). RESULTS: Fifty participants were enrolled. There were strong correlations between CT muscle area and FFM values and mid-arm muscle circumference (P < 0.001). Using FFM-Chamney, all six (100%) participants with low CT muscle area were detected (κ = 0.723). FFM-BIS, arm anthropometry and subjective physical assessment methods detected 28%-38% of participants with low CT muscle area. CONCLUSIONS: BIS-derived FFM using an adjustment algorithm for overhydration was correlated with CT muscle area and had good agreement with muscularity status assessed by CT image analysis. Arm anthropometry and subjective physical assessment techniques were not able to reliably detect participants with low CT muscle area.


Assuntos
Unidades de Terapia Intensiva , Músculo Esquelético , Adulto , Composição Corporal , Estudos Transversais , Impedância Elétrica , Humanos , Músculo Esquelético/diagnóstico por imagem , Estudos Prospectivos , Tomografia Computadorizada por Raios X
10.
Emerg Infect Dis ; 26(4): 811-814, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32187004

RESUMO

We detected West Nile virus (WNV) nucleic acid in crocodiles (Crocodylus niloticus) in Zambia. Phylogenetically, the virus belonged to lineage 1a, which is predominant in the Northern Hemisphere. These data provide evidence that WNV is circulating in crocodiles in Africa and increases the risk for animal and human transmission.


Assuntos
Jacarés e Crocodilos , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genética , Zâmbia/epidemiologia
11.
Public Health ; 184: 17-21, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32564910

RESUMO

OBJECTIVES: The objectives of this study were to examine gambling-related problems, risk factors, help-seeking attitudes, community perceptions, and correlates of problem gambling in a Lao sample of Southeast Asian refugees and immigrants and to discuss cultural implications for the treatment and prevention of gambling problems in Southeast Asian refugee and immigrant populations. STUDY DESIGN: This was a cross-sectional, community-based interview study. METHODS: Participants (N = 200, males = 51%, females = 49%) were recruited from a Lao community center in a major US metropolitan area (convenience sample; community center recruitment and peer nomination). Structured interviews on gambling and substance use were conducted by Lao center staff members in both English and Lao languages. RESULTS: Gambling-related problems were measured using the South Oaks Gambling Screen (SOGS), gambling frequency, and quantity measures. In a previous study, we reported a substantial number of participants from the sample endorsed gambling-related harms and problems (SOGS score of five or more = 24%) and common methods of play were slots, house betting, cards at a casino, and sports betting. Among those endorsing five or more gambling problems, reasons for gambling included making money (68%), social life (31.3%), entertainment (58.3%), and reducing boredom (35.4%). Less commonly endorsed reasons were depression or stress (14.6%) and escape (10.4%). Many participants reported a family history of gambling problems. Those with problem gambling had twice the level of sibling problem gambling histories relative to those without problem gambling (35.4% vs. 11.1%). There were substantially more participants in the problem gambling group who had started gambling before the age of 13 years than in non-problem gamblers (P < .05). Many recognized gambling as a significant issue in the community and reported knowing several individuals affected by gambling-related problems. CONCLUSIONS: Many participants recognized gambling as a significant issue in the Lao community. We include insights gleaned from a research partnership with a community organization. Although data cannot be generalized to the Lao community because of limitations in sampling methodology, participants viewed gambling as a culturally common social practice. Cultural norms affected where community members gamble, types of games, and betting practices. In this context, community members may view gambling-related harms as both a community-level and individual-level concern. These data suggest a significant need for rigorous research to inform policies and a culturally sensitive approach to public health prevention, intervention, and education. We discuss the challenges and cultural barriers to research and community engagement and offer suggestions for prevention and intervention ideas efforts.


Assuntos
Asiático/psicologia , Comportamento Aditivo/etnologia , Emigrantes e Imigrantes/psicologia , Jogo de Azar/etnologia , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Refugiados/psicologia , Adulto , Asiático/estatística & dados numéricos , Estudos Transversais , Emigrantes e Imigrantes/estatística & dados numéricos , Feminino , Jogo de Azar/psicologia , Humanos , Laos/etnologia , Masculino , Refugiados/estatística & dados numéricos , Fatores de Risco , Estados Unidos
12.
Pediatr Surg Int ; 36(1): 11-19, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31673760

RESUMO

Children with chronic idiopathic constipation (CIC) often end up at the surgeon when medical treatments have failed. This opinion piece discusses a recently described pattern of CIC called 'Rapid transit constipation (RTC)' first identified in 2011 as part of surgical workup. RTC was identified using a nuclear medicine gastrointestinal transit study (NMGIT or nuclear transit study) to determine the site of slowing within the bowel and to inform surgical treatment. Unexpectedly, we found that RTC occured in 29% of 1000 transit studies in a retrospective audit. Irritable bowel syndrome (IBS) occurs in 7-21% of the population, with a higher prevalence in young children and with constipation type dominating in the young. While 60% improve with time, 40% continue with symptoms. First-line therapy for IBS in adults is a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols which reduces symptoms in > 70% of patients. In children with functional gastrointestinal disorders, fructose intolerance occurs in 35-55%. Reducing fructose produced significant improvement in 77-82% of intolerant patients. In children with RTC and a positive breath test upon fructose challenge, we found that exclusion of fructose significantly improved constipation, abdominal pain, stool consistency and decreased laxative use. We hypothesise that positive breath tests and improvement of pain and bowel frequency with sugar exclusion diets in RTC suggest these children have IBS-C. These observations raise the possibility that many children with CIC could be treated by reducing fructose early in their diet and this might prevent the development of IBS in later life.


Assuntos
Constipação Intestinal/dietoterapia , Intolerância à Frutose/diagnóstico , Trânsito Gastrointestinal/fisiologia , Síndrome do Intestino Irritável/prevenção & controle , Síndromes de Malabsorção/diagnóstico , Testes Respiratórios , Criança , Constipação Intestinal/fisiopatologia , Açúcares da Dieta/efeitos adversos , Incontinência Fecal/etiologia , Intolerância à Frutose/complicações , Doença de Hirschsprung/cirurgia , Humanos , Intestinos/diagnóstico por imagem , Síndromes de Malabsorção/complicações , Complicações Pós-Operatórias , Cintilografia
13.
Proc Biol Sci ; 286(1904): 20190898, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31185859

RESUMO

Homophilous behaviour plays a central role in the formation of human friendships. Individuals form social ties with others that show similar phenotypic traits, independently of relatedness. Evidence of such homophily can be found in bottlenose dolphins ( Tursiops aduncus) in Shark Bay, Western Australia, where females that use marine sponges as foraging tools often associate with other females that use sponges. 'Sponging' is a socially learned, time-consuming behaviour, transmitted from mother to calf. Previous research illustrated a strong female bias in adopting this technique. The lower propensity for males to engage in sponging may be due to its incompatibility with adult male-specific behaviours, particularly the formation of multi-level alliances. However, the link between sponging and male behaviour has never been formally tested. Here, we show that male spongers associated significantly more often with other male spongers irrespective of their level of relatedness. Male spongers spent significantly more time foraging, and less time resting and travelling, than did male non-spongers. Interestingly, we found no difference in time spent socializing. Our study provides novel insights into the relationship between tool use and activity budgets of male dolphins, and indicates social homophily in the second-order alliance composition of tool-using bottlenose dolphins.


Assuntos
Comportamento Animal , Golfinho Nariz-de-Garrafa/fisiologia , Comportamento Social , Comportamento de Utilização de Ferramentas , Animais , Feminino , Masculino , Caracteres Sexuais , Aprendizado Social
14.
Br J Surg ; 106(10): 1341-1351, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31282584

RESUMO

BACKGROUND: It remains controversial whether neoadjuvant chemoradiation (nCRT) for oesophageal cancer influences operative morbidity, in particular pulmonary, and quality of life. This study combined clinical outcome data with systematic evaluation of pulmonary physiology to determine the impact of nCRT on pulmonary physiology and clinical outcomes in locally advanced oesophageal cancer. METHODS: Consecutive patients treated between 2010 and 2016 were included. Three-dimensional conformal radiation was standard, with a lung dose-volume histogram of V20 less than 25 per cent, and total radiation between 40 and 41·4 Gy. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and diffusion capacity for carbon monoxide (DLCO) were assessed at baseline and 1 month after nCRT. Radiation-induced lung injury (grade 2 or greater), comprehensive complications index (CCI) and pulmonary complications were monitored prospectively. Health-related quality of life was assessed among disease-free patients in survivorship. RESULTS: Some 228 patients were studied. Comparing pulmonary physiology values before with those after nCRT, FEV1 decreased from mean(s.d.) 96·8(17·7) to 91·5(20·4) per cent (-3·6(10·6) per cent; P < 0·001), FVC from 104·9(15·6) to 98·1(19·8) per cent (-3·2(11·9) per cent; P = 0·005) and DLCO from 97·6(20·7) to 82·2(20·4) per cent (-14·8(14·0) per cent; P < 0·001). Five patients (2·2 per cent) developed radiation-induced lung injury precluding surgical resection. Smoking (P = 0·005) and increased age (P < 0·001) independently predicted percentage change in DLCO. Carboplatin and paclitaxel with 41·4 Gy resulted in a greater DLCO decline than cisplatin and 5-fluorouracil with 40 Gy (P = 0·001). On multivariable analysis, post-treatment DLCO predicted CCI (P = 0·006), respiratory failure (P = 0·020) and reduced physical function in survivorship (P = 0·047). CONCLUSION: These data indicate that modern nCRT alters pulmonary physiology, in particular diffusion capacity, which is linked to short- and longer-term clinical consequences, highlighting a potentially modifiable index of risk.


ANTECEDENTES: El tema de si en el cáncer de esófago la quimiorradioterapia neoadyuvante (neoadjuvant chemoradiation, nCRT) repercute sobre la morbilidad postoperatoria, especialmente sobre la morbilidad pulmonar y la calidad de vida de los pacientes que sobreviven sigue siendo controvertido. Este estudio combina datos sobre resultados clínicos con una evaluación sistemática de la fisiología pulmonar para determinar el impacto de la nCRT sobre la fisiología pulmonar y los resultados clínicos en el cáncer de esófago localmente avanzado. MÉTODOS: Se incluyeron pacientes consecutivos tratados entre 2010-2016. La radioterapia conformal 3D fue la estándar, con un histograma dosis-volumen del pulmón V20 < 25% y radiación entre 40-41,4 Gy. Se evaluaron el volumen espiratorio forzado (forced expiratory volume, FEV1), la capacidad vital forzada (forced vital capacity, FVC) y la capacidad de difusión del monóxido de carbono (diffusion capacity for carbon monoxide, DLCO) al inicio y un mes tras la nCRT. La lesión pulmonar inducida por la radioterapia (EORTC grado ≥ 2), el índice de complicaciones integral (comprehensive complications index, CCI), grado de Clavien-Dindo, y complicaciones pulmonares fueron analizadas de manera prospectiva. Se evaluó la calidad de vida relacionada con la salud entre los pacientes supervivientes libres de enfermedad (EORTC QLQ-C30, OG25, OES18). RESULTADOS: Se estudiaron un total de 228 pacientes. Al comparar los valores de la fisiología pulmonar antes y después de la nCRT respectivamente, la FEV1 disminuyó de 96,8 ± 17,7% a 91,5 ± 20,4% (-3,6 ± 10,6%, P = 0,0002), la FVC de 104,9 ± 15,6 a 98,1 ± 19,8% (-3,2 ± 11,9%, P = 0,005) y la DLCO de 97,6 ± 20,7 a 82,2 ± 20,4% (-14,8 ± 14,0%, P < 0,0001). Cinco pacientes (2,2%) desarrollaron lesión pulmonar relacionada con la radioterapia impidiendo la resección quirúrgica. Los factores predictores independientes de %ΔDLCO fueron el hábito tabáquico (P = 0,005) y la edad avanzada (P < 0,001). El tratamiento con carboplatino/paclitaxel/41,4Gy determinó un mayor descenso de la DLCO en comparación con cisplatino/5-fluorouracilo/40Gy (P = 0,001). En el análisis multivariable, la DLCO tras el tratamiento fue una variable predictora de CCI (P = 0,006), fracaso respiratorio/intubación prolongada (P = 0,020) y reducción de la función física en los supervivientes (P = 0,047). CONCLUSIÓN: Estos datos indican que la moderna nCRT altera la fisiología pulmonar, especialmente la difusión pulmonar, con consecuencias clínicas a corto y largo plazo. La DLCO podría constituir un factor de riesgo potencialmente modificable.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia Adjuvante/métodos , Neoplasias Esofágicas/terapia , Qualidade de Vida , Transtornos Respiratórios/etiologia , Monóxido de Carbono/análise , Carboplatina/administração & dosagem , Esofagectomia/métodos , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Paclitaxel/administração & dosagem , Complicações Pós-Operatórias/etiologia , Cuidados Pré-Operatórios/métodos , Capacidade Vital/fisiologia
15.
Chem Res Toxicol ; 32(3): 526-534, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30784263

RESUMO

Redox-mediated protein modifications control numerous processes in both normal and disease metabolism. Protein sulfenic acids, formed from the oxidation of protein cysteine residues, play a critical role in thiol-based redox signaling. The reactivity of protein sulfenic acids requires their identification through chemical trapping, and this paper describes the use of the triphenylphosphonium (TPP) ion to direct known sulfenic acid traps to the mitochondria, a verified source of cellular reactive oxygen species. Coupling of the TPP group with the 2,4-(dioxocyclohexyl)propoxy (DCP) unit and the bicyclo[6.1.0]nonyne (BCN) group produces two new probes, DCP-TPP and BCN-TPP. DCP-TPP and BCN-TPP react with C165A AhpC-SOH, a model protein sulfenic acid, to form the expected adducts with second-order rate constants of k = 1.1 M-1 s-1 and k = 5.99 M-1 s-1, respectively, as determined by electrospray ionization time-of-flight mass spectrometry. The TPP group does not alter the rate of DCP-TPP reaction with protein sulfenic acid compared to dimedone but slows the rate of BCN-TPP reaction compared to a non-TPP-containing BCN-OH control by 4.6-fold. The hydrophobic TPP group may interact with the protein, preventing an optimal reaction orientation for BCN-TPP. Unlike BCN-OH, BCN-TPP does not react with the protein persulfide, C165A AhpC-SSH. Extracellular flux measurements using A549 cells show that DCP-TPP and BCN-TPP influence mitochondrial energetics, with BCN-TPP producing a drastic decrease in basal respiration, perhaps due to its faster reaction kinetics with sulfenylated proteins. Further control experiments with BCN-OH, TPP-COOH, and dimedone provide strong evidence for mitochondrial localization and accumulation of DCP-TPP and BCN-TPP. These results reveal the compatibility of the TPP group with reactive sulfenic acid probes as a mitochondrial director and support the use of the TPP group in the design of sulfenic acid traps.


Assuntos
Mitocôndrias/efeitos dos fármacos , Compostos Organofosforados/síntese química , Compostos Organofosforados/farmacologia , Proteínas/química , Ácidos Sulfênicos/análise , Células A549 , Humanos , Mitocôndrias/metabolismo , Sondas Moleculares/química , Estrutura Molecular , Compostos Organofosforados/química
16.
Mol Pharm ; 16(6): 2364-2375, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31018096

RESUMO

This study focused on formulating conjugate vaccines targeting oxycodone and heroin for technology transfer, good manufacturing practice (GMP), and clinical evaluation. Lead vaccines used the highly immunogenic carrier protein keyhole limpet hemocyanin (KLH), which poses formulation problems because of its size. To address this barrier to translation, an oxycodone-based hapten conjugated to GMP-grade subunit KLH (OXY-sKLH) and adsorbed on alum adjuvant was studied with regard to carbodiimide coupling reaction time, buffer composition, purification methods for conjugates, conjugate size, state of aggregation, and protein/alum ratio. Vaccine formulations were screened for post-immunization antibody levels and efficacy in reducing oxycodone distribution to the brain in rats. While larger conjugates were more immunogenic, their size prevented characterization of the haptenation ratio by standard analytical methods and sterilization by filtration. To address this issue, conjugation chemistry and vaccine formulation were optimized for maximal efficacy, and conjugate size was measured by dynamic light scattering prior to adsorption to alum. An analogous heroin vaccine (M-sKLH) was also optimized for conjugation chemistry, formulated in alum, and characterized for potency against heroin in rats. Finally, this study found that the efficacy of OXY-sKLH was preserved when co-administered with M-sKLH, supporting the proof of concept for a bivalent vaccine formulation targeting both heroin and oxycodone. This study suggests methods for addressing the unique formulation and characterization challenges posed by conjugating small molecules to sKLH while preserving vaccine efficacy.


Assuntos
Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Vacinas Conjugadas/química , Animais , Hemocianinas/metabolismo , Heroína/toxicidade , Humanos , Oxicodona/toxicidade , Ratos , Vacinas/química , Vacinas/uso terapêutico , Vacinas Conjugadas/uso terapêutico
17.
Arch Virol ; 164(1): 303-307, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30311077

RESUMO

Although canine parvovirus (CPV) causes severe gastroenteritis in dogs globally, information on the molecular epidemiology of the virus is lacking in many African countries. Here, 32 fecal samples collected from diarrheic dogs in Zambia were tested for CPV infection using molecular assays. CPV was detected in 23 samples (71.9%). Genetic characterization revealed the predominance of CPV-2c (91.3%). This finding differs from previous reports in Africa, which indicated that CPV-2a and CPV-2b were most prevalent. Phylogenetically, most Zambian CPVs formed a distinct cluster. This is the first report on the molecular characterization of CPV in Zambia.


Assuntos
Diarreia/veterinária , Doenças do Cão/virologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Parvovirus Canino/isolamento & purificação , Sequência de Aminoácidos , Animais , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Diarreia/epidemiologia , Diarreia/virologia , Doenças do Cão/epidemiologia , Cães , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Zâmbia/epidemiologia
18.
Water Sci Technol ; 79(9): 1627-1638, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31241468

RESUMO

Urban metabolism is increasingly being adopted to guide city planning towards improved water, energy and material efficiency. Stakeholder participation in the adoption of this concept will be important, and hence effective communication will be crucial. This study aimed to determine how urban metabolism has been communicated and interpreted, with attention to water. The approach included (i) literature review, (ii) structured international interviews and (iii) thematic analysis. We demonstrate how diverse language, metaphors, methods, visual imagery, data and information have been used to communicate this complex topic. Maps, Sankey diagrams, concept figures, spider diagrams, pictorial flow diagrams, art, and animation have all been used. We observe barriers to communication in order to understand the communication techniques which may be effective, and clarify issues relating to awareness and target audiences. We include a discussion of the themes that emerged from the research that are relevant for integrated water planning and the power of visual imagery. Inconsistent language is influenced by widely different overarching metaphors which range from 'organism' to 'ecosystem' metabolism. Fragmented data are a major gap for shared understanding. The research provides new understanding of how stakeholders perceive urban water metabolism and its relationship to Integrated urban water management.


Assuntos
Planejamento de Cidades , Abastecimento de Água/estatística & dados numéricos , Austrália , Europa (Continente) , Água
19.
Immunology ; 153(3): 357-367, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28940186

RESUMO

Impaired immune responsiveness is a significant barrier to vaccination of neonates. By way of example, the low seroconversion observed following influenza vaccination has led to restriction of its use to infants over 6 months of age, leaving younger infants vulnerable to infection. Our previous studies using a non-human primate neonate model demonstrated that the immune response elicited following vaccination with inactivated influenza virus could be robustly increased by inclusion of the Toll-like receptor agonist flagellin or R848, either delivered individually or in combination. When delivered individually, R848 was found to be the more effective of the two. To gain insights into the mechanism through which these adjuvants functioned in vivo, we assessed the initiation of the immune response, i.e. at 24 hr, in the draining lymph node of neonate non-human primates. Significant up-regulation of co-stimulatory molecules on dendritic cells could be detected, but only when both adjuvants were present. In contrast, R848 alone could increase the number of cells in the lymph node, presumably through enhanced recruitment, as well as B-cell activation at this early time-point. These changes were not observed with flagellin and the dual adjuvanted vaccine did not promote increases beyond those observed with R848 alone. In vitro studies showed that R848 could promote B-cell activation, supporting a model wherein a direct effect on neonate B-cell activation is an important component of the in vivo potency of R848 in neonates.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Animais Recém-Nascidos/imunologia , Linfócitos B/imunologia , Imidazóis/imunologia , Vacinas contra Influenza/imunologia , Linfonodos/imunologia , Animais , Anticorpos Antivirais/imunologia , Chlorocebus aethiops , Células Dendríticas/imunologia , Flagelina/imunologia , Ativação Linfocitária/imunologia , Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/imunologia , Primatas , Vacinação/métodos
20.
Soft Matter ; 14(26): 5525-5536, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29926037

RESUMO

Recent investigations have shown that deep eutectic solvents provide a suitable environment for self-organisation of biomolecules, in particular phospholipids and proteins. However, the solvation of complex lyophilic moieties by deep eutectic solvents still remains unclear. Here we explore the behaviour of zwitterionic surfactants in choline chloride:glycerol eutectic mixture. Dodecyl-2-(trimethylammonio)ethylphosphate and N-alkyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (alkyl = dodecyl, tetradecyl) surfactants were investigated by means of surface tension, X-ray reflectivity and small-angle neutron scattering. These surfactants were found to remain surface active and form globular micelles in deep eutectic solvents. Still, the surface behaviour of these species was found to differ depending on the headgroup and tail structure. The morphology of the micelles also slightly varies between surfactants, demonstrating differences in the packing of individual monomers. The characteristics of mixtures of the dodecyl surfactants is also reported, showing a deviation from ideal mixing associated with attractive interactions between sulfobetaine and phosphocholine headgroups. Such non-ideality results in variation of the surface behaviour and self-assembly of these surfactant mixtures. The results presented here will potentially lead to the development of new alternatives for drug-delivery, protein solubilisation and biosensing through a better fundamental understanding of the behaviour of zwitterionic surfactants in deep eutectic solvents.

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