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1.
Soc Sci Res ; 120: 103013, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38763532

RESUMO

Subjective well-being (SWB) describes an individual's life evaluation. Direct elicitation methods for SWB via rating scales do not force individuals to trade-off among life domains, whilst best-worst scaling (BWS) approaches only provide relative measures. This paper instead offers a dual-response BWS task, where respondents nominate areas of most and least importance and satisfaction with respect to 11 SWB domains, whilst also eliciting anchoring points to obtain an absolute measure of domain satisfaction. Combining domain satisfaction and importance produces a robust measure of individual SWB, but statistically unique relative to other life satisfaction measures utilizing single- and multi-item ratings, including global satisfaction and those aggregated over SWB domains, as well as eudemonia. Surveying 2500 Australians reveals anchored-BWS improves discrimination amongst domains in terms of importance and satisfaction, illustrating its value as a diagnostic tool for SWB measurement to focus services, policy, and initiatives in areas to most impact wellbeing. This includes highlighting a major discrepancy between health satisfaction and importance, whilst also reporting that SWB is significantly lower for Indigenous, unemployed, middle-aged, males and lower income groups.

2.
J Anat ; 243(1): 1-22, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36929596

RESUMO

The interrelationships of the extant crocodylians Gavialis gangeticus and Tomistoma schlegelii have been historically disputed. Whereas molecular analyses indicate a sister taxon relationship between these two gavialoid species, morphological datasets typically place Gavialis as the outgroup to all other extant crocodylians. Recent morphological-based phylogenetic analyses have begun to resolve this discrepancy, recovering Gavialis as the closest living relative of Tomistoma; however, several stratigraphically early fossil taxa are recovered as closer to Gavialis than Tomistoma, resulting in anomalously early divergence timings. As such, additional morphological data might be required to resolve these remaining discrepancies. 'Tomistoma' dowsoni is an extinct species of gavialoid from the Miocene of North Africa. Utilising CT scans of a near-complete, referred skull, we reconstruct the neuroanatomy and neurosensory apparatus of 'Tomistoma' dowsoni. Based on qualitative and quantitative morphometric comparisons with other crocodyliforms, the neuroanatomy of 'Tomistoma' dowsoni is characterised by an intermediate morphology between the two extant gavialoids, more closely resembling Gavialis. This mirrors the results of recent studies based on the external anatomy of these three species and other fossil gavialoids. Several neuroanatomical features of these species appear to reflect ecological and/or phylogenetic signals. For example, the 'simple' morphology of their neurosensory apparatus is broadly similar to that of other long and narrow-snouted (longirostrine), aquatic crocodyliforms. A dorsoventrally short, anteroposteriorly long endosseous labyrinth is also associated with longirostry. These features indicate that snout and skull morphology, which are themselves partly constrained by ecology, exert an influence on neuroanatomical morphology, as has also been recognised in birds and turtles. Conversely, the presence of a pterygoid bulla in Gavialis and several extinct gavialoids, and its absence in Tomistoma schlegelii, could be interpreted as a phylogenetic signal of crocodylians more closely related to Gavialis than to Tomistoma. Evaluation of additional fossil gavialoids will be needed to further test whether these and other neuroanatomical features primarily reflect a phylogenetic or ecological signal. By incorporating such previously inaccessible information of extinct and extant gavialoids into phylogenetic and macroecological studies, we can potentially further constrain the clade's interrelationships, as well as evaluate the timing and ecological association of the evolution of these neuroanatomical features. Finally, our study supports recent phylogenetic analyses that place 'Tomistoma' dowsoni as being phylogenetically closer to Gavialis gangeticus than to Tomistoma schlegelii, indicating the necessity of a taxonomic revision of this fossil species.


Assuntos
Jacarés e Crocodilos , Neuroanatomia , Animais , Filogenia , Jacarés e Crocodilos/anatomia & histologia , Crânio/anatomia & histologia , Fósseis , África do Norte
3.
Health Econ ; 32(4): 953-969, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36639879

RESUMO

Extreme temperatures are known to cause adverse health outcomes. Yet knowledge on the magnitude of this effect in developing countries is limited due to data availability and reliability issues. Collecting data for 2872 counties in China, we estimate the effects of daily temperatures on the monthly mortality rate. The results indicate that an additional day for which the maximum temperature is 38°C or above on average increases the monthly mortality rate by about 1.7% relative to if that day's maximum temperature had been in the range 16-21°C. This is after deducting deaths harvested from the subsequent month. Higher gross domestic product per capita at the county level is associated with lower mortality effects of hot and cold days. Improved dwelling conditions are found to be associated with a lower mortality effect of hot days and improved local healthcare infrastructure to be associated with a lower mortality effect of cold days. In the absence of strong adaptation efforts, the estimates suggest net upward pressure on annual mortality rates over coming decades in many populous counties, especially under more extreme climate change scenarios.


Assuntos
Temperatura Baixa , Temperatura Alta , Humanos , Temperatura , Reprodutibilidade dos Testes , China/epidemiologia , Mortalidade
4.
Aust J Educ ; 67(2): 124-142, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38602930

RESUMO

This article discusses findings from a recent survey (n = 297) of teachers' views of both their own and their students' experiences during the 2021 enforced emergency remote schooling period occurring in New South Wales Australia, due to the COVID-19 pandemic. The quantitative analysis reported here explores teachers' views regarding teaching and learning during this challenging period. It identifies three latent constructs, learning, assessment, and interaction, and then uses structural equation modelling to identify the perceived impact of these constructs on student and teacher wellbeing. The remote schooling period had a significant negative impact for teachers and their students across a range of elements of teaching and learning, as well as wellbeing. Student learning experiences and their peer interactions were found to be strong predictors of students' wellbeing outcomes. Assessment design and teachers' feedback to students were significant in predicting levels of teacher wellbeing. Future research directions are also provided.

5.
Health Promot Int ; 36(1): 187-195, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32529220

RESUMO

Generic medicines have been available to consumers for ∼40 years, with varying degrees of uptake in different countries. Despite offering equivalent therapeutic qualities, generic medicines still struggle to be accepted by consumers. This study examines the role of a consumer's affective state and framing effects on the purchase of a branded versus a generic pharmaceutical product. These issues are examined in an experiment, with independent manipulations of consumer anxiety levels and the framing of generic alternatives by the pharmacist. The sample comprised 426 men and women within Australia who completed an online survey with a scenario of purchasing a pharmaceutical after visiting a General Practitioner. Results indicate that those consumers experiencing higher levels of anxiety and where the doctor prescribed the branded medicine are more likely to choose branded medicines over cheaper, generic alternatives. The effect of framing the generic alternative as either 'generic' or 'cheaper' was not significant.


Assuntos
Transtornos de Ansiedade , Medicamentos Genéricos , Ansiedade/tratamento farmacológico , Austrália , Medicamentos Genéricos/uso terapêutico , Feminino , Humanos , Masculino , Farmacêuticos
6.
Cytotherapy ; 22(6): 313-321, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32273232

RESUMO

BACKGROUND: Critical limb ischemia (CLI) is the most severe manifestation of peripheral vascular disease. Revascularization is the preferred therapy, but it is not achievable in 25%-40% of patients due to diffuse anatomic distribution of the disease or medical comorbidities. No-option CLI represents an unmet medical need. Mesenchymal stromal cells (MSCs) may provide salvage therapy through their angiogenic and tissue-trophic properties. This article reports a phase 1b clinical study examining the safety and feasibility of intramuscular transplantation of autologous bone-marrow MSCs for patients with no-option CLI. METHODS: Twelve patients were enrolled in the clinical trial, and nine proceeded to bone marrow aspiration and culture expansion of MSCs. RESULTS: A high rate of karyotype abnormality (>30%) was detected in the produced cell batches, resulting in failure of release for clinical administration. Four patients were treated with the investigational medicinal product (IMP), three with a low dose of 20 × 106 MSCs and one with a mid-dose of 40 × 106 MSCs. There were no serious adverse events related to trial interventions, including bone marrow aspiration, IMP injection or therapy. CONCLUSIONS: The results of this trial conclude that an autologous cell therapy approach with MSCs for critical limb ischemia is limited by the high rate of karyotype abnormalities.


Assuntos
Isquemia/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Doença Arterial Periférica/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica , Medula Óssea , Feminino , Humanos , Isquemia/cirurgia , Cariótipo , Perna (Membro)/irrigação sanguínea , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Doença Arterial Periférica/cirurgia , Terapia de Salvação , Transplante Autólogo , Resultado do Tratamento
7.
Nature ; 514(7522): 348-50, 2014 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-25252975

RESUMO

The ability to store energy on the electric grid would greatly improve its efficiency and reliability while enabling the integration of intermittent renewable energy technologies (such as wind and solar) into baseload supply. Batteries have long been considered strong candidate solutions owing to their small spatial footprint, mechanical simplicity and flexibility in siting. However, the barrier to widespread adoption of batteries is their high cost. Here we describe a lithium-antimony-lead liquid metal battery that potentially meets the performance specifications for stationary energy storage applications. This Li||Sb-Pb battery comprises a liquid lithium negative electrode, a molten salt electrolyte, and a liquid antimony-lead alloy positive electrode, which self-segregate by density into three distinct layers owing to the immiscibility of the contiguous salt and metal phases. The all-liquid construction confers the advantages of higher current density, longer cycle life and simpler manufacturing of large-scale storage systems (because no membranes or separators are involved) relative to those of conventional batteries. At charge-discharge current densities of 275 milliamperes per square centimetre, the cells cycled at 450 degrees Celsius with 98 per cent Coulombic efficiency and 73 per cent round-trip energy efficiency. To provide evidence of their high power capability, the cells were discharged and charged at current densities as high as 1,000 milliamperes per square centimetre. Measured capacity loss after operation for 1,800 hours (more than 450 charge-discharge cycles at 100 per cent depth of discharge) projects retention of over 85 per cent of initial capacity after ten years of daily cycling. Our results demonstrate that alloying a high-melting-point, high-voltage metal (antimony) with a low-melting-point, low-cost metal (lead) advantageously decreases the operating temperature while maintaining a high cell voltage. Apart from the fact that this finding puts us on a desirable cost trajectory, this approach may well be more broadly applicable to other battery chemistries.

8.
Eur J Vasc Endovasc Surg ; 56(3): 410-424, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29895399

RESUMO

OBJECTIVES: A systematic review and meta-analysis was performed to determine the incidence of thrombotic events following great saphenous vein (GSV) endovenous thermal ablation (EVTA). METHODS: MEDLINE, Embase and conference abstracts were searched. Eligible studies were randomised controlled trials and case series that included at least 100 patients who underwent GSV EVTA (laser ablation or radiofrequency ablation [RFA]) with duplex ultrasound (DUS) within 30 days. The systematic review focused on the complications of endovenous heat induced thrombosis (EHIT), deep venous thrombosis (DVT), and pulmonary embolism (PE). The primary outcome for the meta-analysis was deep venous thrombotic events which were defined as DVT or EHIT Type 2, 3, or 4. Secondary outcomes for the meta-analysis were EHIT Type 2, 3, or 4, DVT and PE. Subgroup analyses were performed for both the RFA and EVLA groups. Pooled proportions were calculated using random effects modelling. RESULTS: Fifty-two studies (16,398 patients) were included. Thrombotic complications occurred infrequently. Deep venous thrombotic events occurred in 1.7% of cases (95% CI 0.9-2.7%) (25 studies; 10,012 patients; 274 events). EHIT Type 2, 3, or 4 occurred in 1.4% of cases (95% CI 0.8-2.3%) (26 studies; 10,225 patients; 249 events). DVT occurred in 0.3% of cases (95% CI = 0.2%-0.5%) (49 studies; 15,676 patients; 48 events). PE occurred in 0.1% of cases (95% CI = 0.1-0.2%) (29 studies; 8223 patients; 3 events). Similar results were found when the RFA and EVLA groups were analysed separately. CONCLUSION: Thrombotic events occur infrequently following GSV EVTA. Given the large numbers of procedures worldwide and the potential for serious consequences, further research is needed on the burden of these complications and their management.


Assuntos
Ablação por Cateter/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Temperatura Alta/efeitos adversos , Terapia a Laser/efeitos adversos , Veia Safena/cirurgia , Varizes/cirurgia , Trombose Venosa/epidemiologia , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Veia Safena/diagnóstico por imagem , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Varizes/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem
9.
Appetite ; 116: 323-338, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28479408

RESUMO

Front-of-pack attributes have the potential to affect parents' food choices on behalf of their children and form one avenue through which strategies to address the obesogenic environment can be developed. Previous work has focused on the isolated effects of nutrition and health information (e.g. labeling systems, health claims), and how parents trade off this information against co-occurring marketing features (e.g. product imagery, cartoons) is unclear. A Discrete Choice Experiment was utilized to understand how front-of-pack nutrition, health and marketing attributes, as well as pricing, influenced parents' choices of cereal for their child. Packages varied with respect to the two elements of the Australian Health Star Rating system (stars and nutrient facts panel), along with written claims, product visuals, additional visuals, and price. A total of 520 parents (53% male) with a child aged between five and eleven years were recruited via an online panel company and completed the survey. Product visuals, followed by star ratings, were found to be the most significant attributes in driving choice, while written claims and other visuals were the least significant. Use of the Health Star Rating (HSR) system and other features were related to the child's fussiness level and parents' concerns about their child's weight with parents of fussy children, in particular, being less influenced by the HSR star information and price. The findings suggest that front-of-pack health labeling systems can affect choice when parents trade this information off against marketing attributes, yet some marketing attributes can be more influential, and not all parents utilize this information in the same way.


Assuntos
Comportamento de Escolha , Rotulagem de Alimentos , Preferências Alimentares , Marketing , Adolescente , Adulto , Austrália , Criança , Pré-Escolar , Comportamento do Consumidor , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Valor Nutritivo , Pais , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
10.
Ann Vasc Surg ; 35: 60-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27263823

RESUMO

BACKGROUND: To evaluate the association between inflammatory markers expressed as neutrophil-lymphocyte ratio (NLR) and process of arteriovenous fistula (AVF) maturation. METHODS: A retrospective review of patients with end-stage renal disease referred for formation of a new AVF in one center. Patients referred to the vascular service in the University Hospital of Limerick for creation of vascular access between 2009 and 2013. The association between NLR, calculated from preoperative blood tests, and functional fistula maturation, as determined by successful use of the AVF for 6 consecutive hemodialysis sessions, was investigated using univariate and logistic regression analyses. A logistic regression analysis was carried out to assess potential influence from other factors related to AVF maturation. Stepwise regression test was performed including the NLR. RESULTS: Overall AVF functional maturation rate in our study was 53.7% (66/123). Patients with matured AVFs had an NLR of 4.850 (1.8-15.7) compared with 3.554 (1.7-15.0); this difference was found to be significant (P = 0.024). Female gender (P = 0.008) and a history of kidney transplant (P = 0.004) were the only independent factors of fistula maturation outcome in a logistic regression model. CONCLUSION: Increased level of NLR was found to be associated with fistula maturation; however, more studies are needed to validate this finding.


Assuntos
Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica/terapia , Contagem de Linfócitos , Linfócitos , Neutrófilos , Diálise Renal , Adulto , Idoso , Área Sob a Curva , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Feminino , Hospitais Universitários , Humanos , Irlanda , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
11.
Int Wound J ; 11(4): 404-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23078587

RESUMO

The aim of this study was to determine the rate of venous ulcer recurrence and the level of compliance in patients wearing European class 1 or class 2 compression stockings. A total of 100 patients with healed venous leg ulcers were recruited, and were randomised to either class 1 (n = 50) or class 2 (n = 50) compression stockings. Follow-up was at 1 week, 3, 6, 9 and 12 months to monitor ulcer recurrence and compliance. Patients had a duplex scan to identify the source of venous incompetence. The rate of ulcer recurrence after 12 months was 16·1%, and the difference in recurrence rate between classes was not statistically significant (P = 0·287) although greater numbers in class 1 developed a recurrence. Participants (88·9%) were compliant; non-compliant patients were at a significantly greater risk of recurrence (P≤ 0·0001). Thirteen patients had both superficial and deep incompetence; those randomised to class 1 stockings (n = 4) developed ulcer recurrence. Patients with a history of multiple episodes of ulceration were more likely to develop a recurrence (P = 0·001). The lowest venous ulcer recurrence rates were seen in patients who were compliant with hosiery regardless of the compression level. Patients with both superficial and deep incompetence had a lower rate of recurrence with class 2 compression.


Assuntos
Úlcera da Perna/terapia , Cooperação do Paciente , Meias de Compressão , Cicatrização , Idoso , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Recidiva , Fatores de Tempo , Resultado do Tratamento
12.
Anat Rec (Hoboken) ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39228104

RESUMO

Eosuchus lerichei is a gavialoid crocodylian from late Paleocene marine deposits of northwestern Europe, known from a skull and lower jaws, as well as postcrania. Its sister taxon relationship with the approximately contemporaneous species Eosuchus minor from the east coast of the USA has been explained through transoceanic dispersal, indicating a capability for salt excretion that is absent in extant gavialoids. However, there is currently no anatomical evidence to support marine adaptation in extinct gavialoids. Furthermore, the placement of Eosuchus within Gavialoidea is labile, with some analyses supporting affinities with the Late Cretaceous to early Paleogene "thoracosaurs." Here we present novel data on the internal and external anatomy of the skull of E. lerichei that enables a revised diagnosis, with 6 autapormorphies identified for the genus and 10 features that enable differentiation of the species from Eosuchus minor. Our phylogenetic analyses recover Eosuchus as an early diverging gavialid gavialoid that is not part of the "thoracosaur" group. In addition to thickened semi-circular canal walls of the endosseous labyrinth and paratympanic sinus reduction, we identify potential osteological correlates for salt glands in the internal surface of the prefrontal and lacrimal bones of E. lerichei. These salt glands potentially provide anatomical evidence for the capability of transoceanic dispersal within Eosuchus, and we also identify them in the Late Cretaceous "thoracosaur" Portugalosuchus. Given that the earliest diverging and stratigraphically oldest gavialoids either have evidence for a nasal salt gland and/or have been recovered from marine deposits, this suggests the capacity for salt excretion might be ancestral for Gavialoidea. Mapping osteological and geological evidence for marine adaptation onto a phylogeny indicates that there was probably more than one independent loss/reduction in the capacity for salt excretion in gavialoids.

13.
Sci Adv ; 10(16): eadk4492, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640243

RESUMO

Approximately 3.3 billion people live with the threat of Plasmodium vivax malaria. Infection can result in liver-localized hypnozoites, which when reactivated cause relapsing malaria. This work demonstrates that an enzyme-cleavable polymeric prodrug of tafenoquine addresses key requirements for a mass administration, eradication campaign: excellent subcutaneous bioavailability, complete parasite control after a single dose, improved therapeutic window compared to the parent oral drug, and low cost of goods sold (COGS) at less than $1.50 per dose. Liver targeting and subcutaneous dosing resulted in improved liver:plasma exposure profiles, with increased efficacy and reduced glucose 6-phosphate dehydrogenase-dependent hemotoxicity in validated preclinical models. A COGS and manufacturability analysis demonstrated global scalability, affordability, and the ability to redesign this fully synthetic polymeric prodrug specifically to increase global equity and access. Together, this polymer prodrug platform is a candidate for evaluation in human patients and shows potential for P. vivax eradication campaigns.


Assuntos
Antimaláricos , Malária Vivax , Malária , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Aminoquinolinas/efeitos adversos , Malária/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Malária Vivax/induzido quimicamente , Fígado
14.
Public Underst Sci ; 32(2): 224-246, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35912942

RESUMO

People are increasingly exposed to conflicting health information and must navigate this information to make numerous decisions, such as which foods to consume, a process many find difficult. Although some consumers attribute these disagreements to aspects related to uncertainty and complexity of research, many use a narrower set of credibility-based explanations. Experts' views on disagreements are underinvestigated and lack explicit identification and classification of the differences in causes for disagreement. Consequently, there is a gap in existing literature to understand the range of reasons for these contradictions. Combining the findings from a literature study and expert interviews, a taxonomy of disagreements was developed. It identifies 10 types of disagreement classified under three dimensions: informant-, information- and uncertainty-related causes for disagreement. The taxonomy may assist with adoption of more effective strategies to deal with conflicting information and contributes to research and practice of science communication in the context of disagreement.


Assuntos
Comunicação , Dissidências e Disputas , Humanos , Incerteza
15.
Ecol Evol ; 13(11): e10687, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020672

RESUMO

Flowers come in a variety of colours, shapes, sizes and odours. Flowers also differ in the quality and quantity of nutritional reward they provide to entice potential pollinators to visit. Given this diversity, generalist flower-visiting insects face the considerable challenge of deciding which flowers to feed on and which to ignore. Working with real flowers poses logistical challenges due to correlations between flower traits, maintenance costs and uncontrolled variables. Here, we overcome this challenge by designing multimodal artificial flowers that varied in visual, olfactory and reward attributes. We used artificial flowers to investigate the impact of seven floral attributes (three visual cues, two olfactory cues and two rewarding attributes) on flower visitation and species richness. We investigated how flower attributes influenced two phases of the decision-making process: the decision to land on a flower, and the decision to feed on a flower. Artificial flowers attracted 890 individual insects representing 15 morphospecies spanning seven arthropod orders. Honeybees were the most common visitors accounting for 46% of visitors. Higher visitation rates were driven by the presence of nectar, the presence of linalool, flower shape and flower colour and was negatively impacted by the presence of citral. Species richness was driven by the presence of nectar, the presence of linalool and flower colour. For hymenopterans, the probability of landing on the artificial flowers was influenced by the presence of nectar or pollen, shape and the presence of citral and/or linalool. The probability of feeding increased when flowers contained nectar. For dipterans, the probability of landing on artificial flowers increased when the flower was yellow and contained linalool. The probability of feeding increased when flowers contained pollen, nectar and linalool. Our results demonstrate the multi-attribute nature of flower preferences and highlight the usefulness of artificial flowers as tools for studying flower visitation in wild insects.

16.
RNA ; 16(12): 2553-63, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20940339

RESUMO

Effective small interfering RNA (siRNA)-mediated therapeutics require the siRNA to be delivered into the cellular RNA-induced silencing complex (RISC). Quantitative information of this essential delivery step is currently inferred from the efficacy of gene silencing and siRNA uptake in the tissue. Here we report an approach to directly quantify siRNA in the RISC in rodents and monkey. This is achieved by specific immunoprecipitation of the RISC from tissue lysates and quantification of small RNAs in the immunoprecipitates by stem-loop PCR. The method, expected to be independent of delivery vehicle and target, is label-free, and the throughput is acceptable for preclinical animal studies. We characterized a lipid-formulated siRNA by integrating these approaches and obtained a quantitative perspective on siRNA tissue accumulation, RISC loading, and gene silencing. The described methodologies have utility for the study of silencing mechanism, the development of siRNA therapeutics, and clinical trial design.


Assuntos
Técnicas de Transferência de Genes , RNA Interferente Pequeno/genética , Animais , Animais Geneticamente Modificados , Anticorpos/isolamento & purificação , Anticorpos/metabolismo , Anticorpos/farmacologia , Especificidade de Anticorpos , Proteínas Argonautas , Células Cultivadas , Fator de Iniciação 2 em Eucariotos/imunologia , Fator de Iniciação 2 em Eucariotos/metabolismo , Estudos de Avaliação como Assunto , Feminino , Inativação Gênica/fisiologia , Marcação de Genes/métodos , Técnicas de Transferência de Genes/normas , Humanos , Imunoprecipitação/métodos , Imunoprecipitação/normas , Macaca mulatta , Camundongos , Camundongos Endogâmicos ICR , Ligação Proteica , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Roedores
17.
Org Biomol Chem ; 10(34): 6980-6, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22833145

RESUMO

A rapid and efficient protocol to afford the title compound 2-[(18)F]-fluoro-2,2-difluoroethyl tosylate ([(18)F]7b) is described. Starting from [(18)F]fluoride ion, labelling reagent 7b was obtained in good yields and a high specific radioactivity. Compound ([(18)F]7b) was then used to synthesise a prospective radiotracer for PET-imaging in dementia.


Assuntos
Compostos de Tosil/química , Compostos de Tosil/síntese química , Radioisótopos de Flúor , Marcação por Isótopo , Tomografia por Emissão de Pósitrons , Radioquímica
18.
Mol Ther ; 19(3): 567-75, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21179008

RESUMO

A major hurdle for harnessing small interfering RNA (siRNA) for therapeutic application is an effective and safe delivery of siRNA to target tissues and cells via systemic administration. While lipid nanoparticles (LNPs) composed of a cationic lipid, poly-(ethylene glycol) lipid and cholesterol, are effective in delivering siRNA to hepatocytes via systemic administration, they may induce multi-faceted toxicities in a dose-dependent manner, independently of target silencing. To understand the underlying mechanism of toxicities, pharmacological probes including anti-inflammation drugs and specific inhibitors blocking different pathways of innate immunity were evaluated for their abilities to mitigate LNP-siRNA-induced toxicities in rodents. Three categories of rescue effects were observed: (i) pretreatment with a Janus kinase (Jak) inhibitor or dexamethasone abrogated LNP-siRNA-mediated lethality and toxicities including cytokine induction, organ impairments, thrombocytopenia and coagulopathy without affecting siRNA-mediated gene silencing; (ii) inhibitors of PI3K, mammalian target of rapamycin (mTOR), p38 and IκB kinase (IKK)1/2 exhibited a partial alleviative effect; (iii) FK506 and etoricoxib displayed no protection. Furthermore, knockout of Jak3, tumor necrosis factor receptors (Tnfr)p55/p75, interleukin 6 (IL-6) or interferon (IFN)-γ alone was insufficient to alleviate LNP-siRNA-associated toxicities in mice. These indicate that activation of innate immune response is a primary trigger of systemic toxicities and that multiple innate immune pathways and cytokines can mediate toxic responses. Jak inhibitors are effective in mitigating LNP-siRNA-induced toxicities.


Assuntos
Inibidores Enzimáticos/metabolismo , Janus Quinases/antagonistas & inibidores , Lipídeos , Nanopartículas , RNA Interferente Pequeno/toxicidade , Animais , Citocinas/sangue , Dexametasona/metabolismo , Etoricoxib , Feminino , Técnicas de Inativação de Genes , Quinase I-kappa B/antagonistas & inibidores , Interferon gama/genética , Interleucina-6/genética , Janus Quinases/genética , Lipídeos/química , Lipídeos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inibidores de Fosfoinositídeo-3 Quinase , Piridinas/metabolismo , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Tipo II do Fator de Necrose Tumoral/genética , Sulfonas/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Tacrolimo/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
19.
Nat Commun ; 13(1): 583, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136074

RESUMO

Establishing a permanent human presence on the Moon or Mars requires a secure supply of oxygen for life support and refueling. The electrolysis of water has attracted significant attention in this regard as water-ice may exist on both the Moon and Mars. However, to date there has been no study examining how the lower gravitational fields on the Moon and Mars might affect gas-evolving electrolysis when compared to terrestrial conditions. Herein we provide experimental data on the effects of gravitational fields on water electrolysis from 0.166 g (lunar gravity) to 8 g (eight times the Earth's gravity) and show that electrolytic oxygen production is reduced by around 11% under lunar gravity with our system compared to operation at 1 g. Moreover, our results indicate that electrolytic data collected using less resource-intensive ground-based experiments at elevated gravity (>1 g) may be extrapolated to gravitational levels below 1 g.

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