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1.
Biomaterials ; 285: 121539, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35500393

RESUMO

Lung cancer is a major contributor to cancer-related death worldwide. siRNA nanomedicines are powerful tools for cancer therapeutics. However, there are challenges to overcome to increase siRNA delivery to solid tumors, including penetration of nanoparticles into a complex microenvironment following systemic delivery while avoiding rapid clearance by the reticuloendothelial system, and limited siRNA release from endosomes once inside the cell. Here we characterized cell uptake, intracellular trafficking, and gene silencing activity of miktoarm star polymer (PDMAEMA-POEGMA) nanoparticles (star nanoparticles) complexed to siRNA in lung cancer cells. We investigated the potential of nebulized star-siRNA nanoparticles to accumulate into orthotopic mouse lung tumors to inhibit expression of two genes [ßIII-tubulin, Polo-Like Kinase 1 (PLK1)] which: 1) are upregulated in lung cancer cells; 2) promote tumor growth; and 3) are difficult to inhibit using chemical drugs. Star-siRNA nanoparticles internalized into lung cancer cells and escaped the endo-lysosomal pathway to inhibit target gene expression in lung cancer cells in vitro. Nebulized star-siRNA nanoparticles accumulated into lungs and silenced the expression of ßIII-tubulin and PLK1 in mouse lung tumors, delaying aggressive tumor growth. These results demonstrate a proof-of-concept for aerosol delivery of star-siRNA nanoparticles as a novel therapeutic strategy to inhibit lung tumor growth.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Aerossóis , Animais , Linhagem Celular Tumoral , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos , Nanopartículas/química , Polímeros/química , RNA Interferente Pequeno/genética , Tubulina (Proteína) , Microambiente Tumoral
2.
Br J Surg ; 107(8): 1004-1012, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32250452

RESUMO

BACKGROUND: This paper describes the development and validation of an electronic personal assessment questionnaire for vascular conditions (ePAQ-VAS) that captures the symptomatology, quality of life and clinically relevant data of patients presenting to vascular services. METHODS: A two-stage survey was conducted in patients attending a tertiary vascular department. Patients completed the ePAQ-VAS remotely online, or on site using an electronic tablet. In the first stage of the survey, the responses were used to perform confirmatory factor analysis to assess the construct validity and remove redundant items. The internal reliability of disease-specific scales was investigated. In the second stage of the survey, the acceptability, known-group validity, test-retest reliability, and responsiveness of ePAQ-VAS was assessed. RESULTS: In total, 721 patients completed ePAQ-VAS. Their mean(s.d.) age was 63·5(15·7) years and 468 (64·9 per cent) were men. Some 553 patients (76·7 per cent) completed the questionnaire in clinic and the remainder completed the questionnaire online. The results of the confirmatory factor analysis confirmed the conceptual model for ePAQ-VAS structure and eliminated six items. Internal reliability was acceptable for all the scales (Cronbach's α greater than 0·7). The test-retest reliability measured by the intraclass correlation coefficient ranged from 0·65 to 0·99. The results showed that the instrument was responsive over time with the standardized response mean ranging from 0·69 to 1·60. CONCLUSION: ePAQ-VAS is a holistic data-collection process that is relevant to vascular service users and has potential to contribute to patient-focused care and the collection of aggregate data for service evaluation. A demonstration version of the final version of ePAQ can be viewed at http://demo-questionnaire.epaq.co.uk/home/project?id=VASC_1.7&page=1.


ANTECEDENTES: Este artículo describe el desarrollo y la validación de un cuestionario electrónico de evaluación personal para enfermedades vasculares (ePAQ-VAS) que incluye la sintomatología, la calidad de vida y los datos clínicamente relevantes para los pacientes que son atendidos en los servicios de patología vascular. MÉTODOS: Se llevó a cabo una encuesta en dos fases entre los pacientes atendidos en un servicio de patología vascular de tercer nivel. Los pacientes completaron el cuestionario ePAQ-VAS a distancia en línea o bien en el centro hospitalario mediante una tableta electrónica. En la primera fase de la encuesta, las respuestas se utilizaron para realizar un análisis factorial de confirmación para evaluar la validez del diseño y eliminar los elementos redundantes. Se investigó la fiabilidad interna de las escalas específicas de la enfermedad. En la segunda fase de la encuesta, se evaluó la aceptabilidad, la validez de grupo conocida, la fiabilidad test-retest y la capacidad de respuesta del ePAQ-VAS. RESULTADOS: En total, 721 pacientes completaron el ePAQ-VAS, la edad media fue de 63,5 años (DE 15,7); el 64,9% eran varones (468); el 76% de los pacientes (553) completaron el cuestionario en la clínica y los pacientes restantes lo hicieron electrónicamente a distancia. Los resultados del análisis factorial de confirmación confirmaron el modelo conceptual para la estructura ePAQ-VAS y eliminaron seis ítems. La fiabilidad interna fue aceptable para todas las escalas (alfa de Cronbach > 0,7). La fiabilidad test-retest medida por el coeficiente de correlación intraclase osciló entre 0,65-0,99. Los resultados mostraron que el instrumento responde con el tiempo con una media de respuesta estandarizada que varía de 0,69 a 1,60. CONCLUSIÓN: El ePAQ-VAS es un proceso holístico de recopilación de datos que es relevante para los usuarios de servicios de patología vascular y tiene el potencial de contribuir a la atención centrada en el paciente y a la recopilación de datos agregados para la evaluación del servicio.


Assuntos
Inquéritos e Questionários , Doenças Vasculares/diagnóstico , Adulto , Idoso , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Reprodutibilidade dos Testes
3.
J Appl Microbiol ; 128(4): 1025-1037, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31793161

RESUMO

AIMS: This study aimed to identify the most effective antimicrobial agent from a selection of essential oils (EO) and investigate its bactericidal properties against Pseudomonas aeruginosa. METHODS AND RESULTS: The disc diffusion assay and minimal inhibitory/bactericidal concentration tests were used to identify antimicrobial potential. Several oils exhibited antimicrobial effects at concentrations as low as 0·03% (v/v). Significantly, cinnamon (Cinnamomum zeylanicum) bark EO exhibited a broad-spectrum activity against Gram-negative and Gram-positive bacteria and showed bacteriostatic and bactericidal effects against P. aeruginosa PAO1 at 0·125% (v/v) and all other tested organisms, including known multidrug resistant species. Time-kill assays and metabolic activity tests showed cinnamon oil to exhibit rapid killing, with bactericidal activity observed in ≤6 min at ≥0·5% (v/v). Furthermore, scanning electron microscopy and a membrane permeability assay indicated damage to membrane integrity, loss of turgor and cell collapse. CONCLUSION: Cinnamon bark EO is a broad-spectrum antimicrobial agent capable of rapid killing at low concentrations. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a sound basis for further investigation of the potential of cinnamon bark EO as an alternative to conventional antimicrobial products due to its fast-acting bactericidal properties at low concentrations.


Assuntos
Antibacterianos/farmacologia , Cinnamomum zeylanicum/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Bactérias/classificação , Bactérias/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Testes de Sensibilidade Microbiana
4.
Acta Oncol ; 58(12): 1752-1756, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31512931

RESUMO

Background: Radiation therapy (RT) plays an important role in management of pediatric central nervous system (CNS) malignancies. Centers are increasingly utilizing pencil beam scanning proton therapy (PBS-PT). However, the risk of brainstem necrosis has not yet been reported. In this study, we evaluate the rate of brainstem necrosis in pediatric patients with CNS malignancies treated with PBS-PT.Material and methods: Pediatric patients with non-hematologic CNS malignancies treated with PBS-PT who received dose to the brainstem were included. All procedures were approved by the institutional review board. Brainstem necrosis was defined as symptomatic toxicity. The actuarial rate was analyzed by the Kaplan Meier method.Results: One hundred and sixty-six consecutive patients were reviewed. Median age was 10 years (range 0.5-21 years). Four patients (2.4%) had prior radiation. Median maximum brainstem dose in the treated course was 55.4 Gy[RBE] (range 0.15-61.4 Gy[RBE]). In patients with prior RT, cumulative median maximum brainstem dose was 98.0 Gy [RBE] (range 17.0-111.0 Gy [RBE]). Median follow up was 19.6 months (range, 2.0-63.0). One patient who had previously been treated with twice-daily radiation therapy and intrathecal (IT) methotrexate experienced brainstem necrosis. The actuarial incidence of brainstem necrosis was 0.7% at 24 months (95% CI 0.1-5.1%).Conclusion: The rate of symptomatic brainstem necrosis was extremely low after treatment with PBS-PT in this study. Further work to clarify clinical and dosimetric parameters associated with risk of brainstem necrosis after PBS-PT is needed.


Assuntos
Tronco Encefálico/efeitos da radiação , Neoplasias do Sistema Nervoso Central/radioterapia , Terapia com Prótons/efeitos adversos , Adolescente , Astrocitoma/radioterapia , Tronco Encefálico/patologia , Criança , Pré-Escolar , Ependimoma/radioterapia , Feminino , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Meduloblastoma/radioterapia , Necrose/epidemiologia , Necrose/etiologia , Terapia com Prótons/métodos , Doses de Radiação , Lesões por Radiação/complicações , Reirradiação/efeitos adversos , Adulto Jovem
5.
Anaesthesia ; 74(5): 619-629, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30793289

RESUMO

To avoid potentially fatal wrong-route neuraxial drug errors, international standard ISO 80369-6 specifying a non-Luer neuraxial connector design was published in 2016. We describe usability studies used in development of the design. Thirty-eight doctors and 17 nurses performed simulated procedures on manikins, using devices fitted with Luer connectors or draft ISO 80369-6 'non-Luer' connectors. The procedures included spinal anaesthesia; intrathecal chemotherapy; lumbar puncture, cerebrospinal fluid collection and pressure measurement; epidural catheter placement with bolus injection and critical care use. Participants attempted cross connection between neuraxial connectors and a range of other medical device connectors, including those from the ISO 80369 small-bore connector series. Video recording analysis was used for all assessments. Participants subjectively assessed performance of the draft non-Luer connector, including suitability for routine clinical use. Participants performed 198 procedures. The connector achieved easy, leak-free connections. The willingness of participants to use the non-Luer connectors were: spinal anaesthesia 100%; intrathecal chemotherapy 88%; lumbar puncture, cerebrospinal fluid collection and pressure measurement 93%; epidural catheter placement with bolus injection 78%; critical care use 100%. Concerns raised were generally device related, rather than connector related. Most cross-connection attempts failed, even using above clinical forces and, when successful, were judged of low clinical risk potential; the exception was a malaligned connection between the non-Luer slip and female Luer connectors. This led to revision of the dimensional tolerances of the non-Luer connector to reduce this risk, before publication of the final specification in 2016. We conclude that the ISO 80369-6 neuraxial non-Luer connector is suitable for clinical use.


Assuntos
Raquianestesia/instrumentação , Erros de Medicação/prevenção & controle , Antineoplásicos/administração & dosagem , Competência Clínica , Desenho de Equipamento , Segurança de Equipamentos , Humanos , Injeções Epidurais/instrumentação , Injeções Espinhais/instrumentação , Manequins , Segurança do Paciente , Punção Espinal/instrumentação
6.
Br J Surg ; 104(11): 1424-1432, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28771700

RESUMO

BACKGROUND: Varicose veins can affect quality of life. Patient-reported outcome measures (PROMs) provide a direct report from the patient about the impact of the disease without interpretation from clinicians or anyone else. The aim of this study was to examine the quality of the psychometric evidence for PROMs used in patients with varicose veins. METHODS: A systematic review was undertaken to identify studies that reported the psychometric properties of generic and disease-specific PROMs in patients with varicose veins. Literature searches were conducted in databases including MEDLINE, up to July 2016. The psychometric criteria used to assess these studies were adapted from published recommendations in accordance with US Food and Drug Administration guidance. RESULTS: Nine studies were included which reported on aspects of the development and/or validation of one generic (36-Item Short Form Health Survey, SF-36®) and three disease-specific (Aberdeen Varicose Vein Questionnaire, AVVQ; Varicose Veins Symptoms Questionnaire, VVSymQ®; Specific Quality-of-life and Outcome Response - Venous, SQOR-V) PROMs. The evidence from included studies provided data to support the construct validity, test-retest reliability and responsiveness of the AVVQ. However, its content validity, including weighting of the AVVQ questions, was biased and based on the opinion of clinicians, and the instrument had poor acceptability. VVSymQ® displayed good responsiveness and acceptability rates. SF-36® was considered to have satisfactory responsiveness and internal consistency. CONCLUSION: There is a scarcity of psychometric evidence for PROMs used in patients with varicose veins. These data suggest that AVVQ and SF-36® are the most rigorously evaluated PROMs in patients with varicose veins.


Assuntos
Medidas de Resultados Relatados pelo Paciente , Varizes/cirurgia , Humanos , Psicometria , Inquéritos e Questionários
7.
Br J Surg ; 104(10): 1273-1283, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28632941

RESUMO

BACKGROUND: Hospitals that conduct more procedures on the carotid arteries may achieve better outcomes. In the context of ongoing reconfiguration of UK vascular services, this systematic review was conducted to evaluate the relationship between the volume of carotid procedures and outcomes, including mortality and stroke. METHODS: Searches of electronic databases identified studies that reported the effect of hospital or clinician volume on outcomes. Reference and citation searches were also performed. Inclusion was restricted to European populations on the basis that the model of healthcare delivery is similar across Europe, but differs from that in the USA and elsewhere. Analyses of hospital and clinician volume, and carotid endarterectomy (CEA) and carotid artery stenting (CAS) were conducted separately. RESULTS: Eleven eligible studies were identified (233 411 participants), five from the UK, two from Sweden, one each from Germany, Finland and Italy, and a combined German, Austrian and Swiss population. All studies were observational. Two large studies (179 736 patients) suggested an inverse relationship between hospital volume and mortality (number needed to treat (NNT) as low as 165), and combined mortality and stroke (NNT as low as 93), following CEA. The evidence was less clear for CAS; multiple analyses in three studies did not identify convincing evidence of an association. Limited data are available on the relationship between clinician volume and outcome in CAS; in CEA, an inverse relationship was identified by two of three small studies. CONCLUSION: The evidence from the largest and highest-quality studies included in this review support the centralization of CEA.


Assuntos
Doenças das Artérias Carótidas/cirurgia , Endarterectomia das Carótidas/estatística & dados numéricos , Hospitais com Alto Volume de Atendimentos/estatística & dados numéricos , Stents/estatística & dados numéricos , Endarterectomia das Carótidas/efeitos adversos , Endarterectomia das Carótidas/mortalidade , Europa (Continente) , Mortalidade Hospitalar , Humanos , Tempo de Internação , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias , Fatores de Risco , Stents/efeitos adversos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade
8.
Eur J Vasc Endovasc Surg ; 53(1): 77-88, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27856168

RESUMO

OBJECTIVE: To evaluate the relationship between the volume of abdominal aortic aneurysm (AAA) procedures undertaken and the primary outcome of mortality in Europe. Previous systematic reviews of this relationship are outdated and are overwhelmingly based on US data. DATA SOURCES: Comprehensive searching within MEDLINE and other bibliographic databases supplemented by citation searching and hand-searching of journals was undertaken to identify studies that reported the effect of hospital or clinician volume on any reported outcomes in adult, European populations, undergoing AAA repair and published in the last 10 years. METHODS: Two reviewers conducted study selection with independent, duplicate data extraction and quality assessment. A planned meta-analysis was not conducted because of the high risk of bias, the likelihood of individual study subjects being included in more than one study and diversity in the clinical populations studied and methods used. RESULTS: Sixteen studies (n = 237,074 participants) from the UK (n = 11 studies), Germany (n = 3 studies), Norway (n = 1 study), and one from the UK and Sweden were included. Data in the included studies came from administrative databases and clinical registries incorporating a variety of clinical and procedural groups; the study quality was limited by the use of observational study designs. Overall, the evidence favoured the existence of an inverse volume outcome relationship between hospital volume and mortality. Insufficient evidence was available to reach conclusions on the relationship between clinician volume and outcome and between hospital or clinician volume and secondary outcomes including complications and length of hospital stay. CONCLUSIONS: The evidence from this review suggests a relationship between the hospital volume of AAA procedures conducted and short-term mortality; however, as volume typically represents a complex amalgamation of factors further research will be useful to identify the core characteristics of volume that influence improved outcomes.


Assuntos
Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Hospitais/estatística & dados numéricos , Complicações Pós-Operatórias/mortalidade , Procedimentos Cirúrgicos Vasculares/estatística & dados numéricos , Ruptura Aórtica/mortalidade , Ruptura Aórtica/cirurgia , Emergências , Europa (Continente) , Humanos , Tempo de Internação , Procedimentos Cirúrgicos Vasculares/efeitos adversos
9.
Neoplasia ; 18(12): 753-764, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27889644

RESUMO

Pancreatic cancer (PC) is a lethal disease which is characterized by chemoresistance. Components of the cell cytoskeleton are therapeutic targets in cancer. ßIV-tubulin is one such component that has two isotypes-ßIVa and ßIVb. ßIVa and ßIVb isotypes only differ in two amino acids at their C-terminus. Studies have implicated ßIVa-tubulin or ßIVb-tubulin expression with chemoresistance in prostate, breast, ovarian and lung cancer. However, no studies have examined the role of ßIV-tubulin in PC or attempted to identify isotype specific roles in regulating cancer cell growth and chemosensitivity. We aimed to determine the role of ßIVa- or ßIVb-tubulin on PC growth and chemosensitivity. PC cells (MiaPaCa-2, HPAF-II, AsPC1) were treated with siRNA (control, ßIVa-tubulin or ßIVb-tubulin). The ability of PC cells to form colonies in the presence or absence of chemotherapy was measured by clonogenic assays. Inhibition of ßIVa-tubulin in PC cells had no effect chemosensitivity. In contrast, inhibition of ßIVb-tubulin in PC cells sensitized to vinca alkaloids (Vincristine, Vinorelbine and Vinblastine), which was accompanied by increased apoptosis and enhanced cell cycle arrest. We show for the first time that ßIVb-tubulin, but not ßIVa-tubulin, plays a role in regulating vinca alkaloid chemosensitivity in PC cells. The results from this study suggest ßIVb-tubulin may be a novel therapeutic target and predictor of vinca alkaloid sensitivity for PC and warrants further investigation.


Assuntos
Neoplasias Pancreáticas/metabolismo , Tubulina (Proteína)/metabolismo , Antineoplásicos/farmacologia , Apoptose , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Expressão Gênica , Inativação Gênica , Humanos , Neoplasias Pancreáticas/genética , Interferência de RNA , Tubulina (Proteína)/genética , Moduladores de Tubulina/farmacologia , Alcaloides de Vinca/farmacologia
10.
J Environ Radioact ; 162-163: 279-284, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27315448

RESUMO

Radon gas is naturally occurring, and can concentrate in the built environment. It is radioactive and high concentration levels within buildings, including homes, have been shown to increase the risk of lung cancer in the occupants. As a result, several methods have been developed to measure radon. The long-term average radon level determines the risk to occupants, but there is always pressure to complete measurements more quickly, particularly when buying and selling the home. For many years, the three-month exposure using etched-track detectors has been the de facto standard, but a decade ago, Phillips et al. (2003), in a DEFRA funded project, evaluated the use of 1-week and 1-month measurements. They found that the measurement methods were accurate, but the challenge lay in the wide variation in radon levels - with diurnal, seasonal, and other patterns due to climatic factors and room use. In the report on this work, and in subsequent papers, the group proposed methodologies for 1-week, 1-month and 3-month measurements and their interpretation. Other work, however, has suggested that 2-week exposures were preferable to 1-week ones. In practice, the radon remediation industry uses a range of exposure times, and further guidance is required to help interpret these results. This paper reviews the data from this study and a subsequent 4-year study of 4 houses, re-analysing the results and extending them to other exposures, particularly for 2-week and 2-month exposures, and provides comprehensive guidance for the use of etched-track detectors, the value and use of Seasonal Correction Factors (SCFs), the uncertainties in short and medium term exposures and the interpretation of results.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Radônio/análise , Poluição do Ar em Ambientes Fechados/análise , Humanos , Estações do Ano
11.
Inhal Toxicol ; 28(5): 203-15, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27092583

RESUMO

Diet-induced obesity has been suggested to lead to increased susceptibility to air pollutants such as ozone (O3); however, there is little experimental evidence. Thirty day old male and female Brown Norway rats were fed a normal, high-fructose or high-fat diet for 12 weeks and then exposed to O3 (acute - air or 0.8 ppm O3 for 5 h, or subacute - air or 0.8 ppm O3 for 5 h/d 1 d/week for 4 weeks). Body composition was measured non-invasively using NMR. Ventilatory parameters and exploratory behavior were measured after the third week of subacute exposure. Bronchoalveolar lavage fluid (BALF) and blood chemistry data were collected 18 h after acute O3 and 18 h after the fourth week of subacute O3. The diets led to increased body fat in male but not female rats. O3-induced changes in ventilatory function were either unaffected or improved with the fructose and fat diets. O3-induced reduction in exploratory behavior was attenuated with fructose and fat diets in males and partially in females. O3 led to a significant decrease in body fat of males fed control diet but not the fructose or fat diet. O3 led to significant increases in BALF eosinophils, increase in albumin, and reductions in macrophages. Female rats appeared to be more affected than males to O3 regardless of diet. Overall, treatment with high-fructose and high-fat diets attenuated some O3 induced effects on pulmonary function, behavior, and metabolism. Exacerbation of toxicity was observed less frequently.


Assuntos
Poluentes Atmosféricos/toxicidade , Dieta Hiperlipídica , Frutose/farmacologia , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Albuminas/metabolismo , Animais , Contagem de Células Sanguíneas , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/citologia , Ingestão de Alimentos/efeitos dos fármacos , Eosinófilos/citologia , Feminino , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Macrófagos/citologia , Masculino , Atividade Motora/efeitos dos fármacos , Ventilação Pulmonar/efeitos dos fármacos , Ratos
12.
Physiol Behav ; 153: 56-63, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26597120

RESUMO

Chronic exercise is considered as one of the most effective means of countering symptoms of the metabolic syndrome (MS) such as obesity and hyperglycemia. Rodent models of forced or voluntary exercise are often used to study the mechanisms of MS and type 2 diabetes. However, there is little known on the impact of genetic strain on the metabolic response to exercise. We studied the effects of housing rats with running wheels (RW) for 65 days compared to sedentary (SED) housing in five female rat strains: Sprague-Dawley (SD), Long-Evans (LE), Wistar (WIS), spontaneously hypertensive (SHR), and Wistar-Kyoto (WKY). Key parameters measured were total distance run, body composition, food consumption, motor activity, ventilatory responses by plethysmography, and resting metabolic rate (MR). WKY and SHR ran significantly more than the WIS, LE, and SD strains. Running-induced reduction in body fat was affected by strain but not by distance run. LE's lost 6% fat after 21 d of running whereas WKY's lost 2% fat but ran 40% more than LE's. LE and WIS lost body weight while the SHR and WKY strains gained weight during running. Food intake with RW was markedly increased in SHR, WIS, and WKY while LE and SD showed modest increases. Exploratory motor activity was reduced sharply by RW in all but the SD strain. Ventilatory parameters were primarily altered by RW in the SHR, WKY, and WIS strains. MR was unaffected by RW. In an overall ranking of physiological and behavioral responses to RW, the SD strain was considered the least responsive whereas the WIS was scored as most responsive. In terms of RW-induced fat loss, the LE strain appears to be the most ideal. These results should be useful in the future selection of rat models to study benefits of volitional exercise.


Assuntos
Tecido Adiposo/metabolismo , Metabolismo Basal/genética , Ingestão de Alimentos/genética , Atividade Motora/genética , Ventilação Pulmonar/genética , Redução de Peso/genética , Animais , Composição Corporal , Ingestão de Líquidos , Comportamento Exploratório , Feminino , Ratos , Ratos Endogâmicos
13.
Opt Express ; 23(15): 19542-51, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26367612

RESUMO

The Diode Pumped Optical Laser for Experiments (DiPOLE) project at the Central Laser Facility aims to develop a scalable, efficient high pulse energy diode pumped laser amplifier system based on cryogenic gas cooled, multi-slab ceramic Yb:YAG technology. We present recent results obtained from a scaled down prototype laser system designed for operation at 10 Hz pulse repetition rate. At 140 K, the system generated 10.8 J of energy in a 10 ns pulse at 1029.5 nm when pumped by 48 J of diode energy at 940 nm, corresponding to an optical to optical conversion efficiency of 22.5%. To our knowledge, this represents the highest pulse energy obtained from a cryo cooled Yb laser to date and the highest efficiency achieved by a multi-Joule diode pumped solid state laser system. Additionally, we demonstrated shot-to-shot energy stability of 0.85% rms for the system operated at 7 J, 10 Hz during several runs lasting up to 6 hours, with more than 50 hours in total. We also demonstrated pulse shaping capability and report on beam, wavefront and focal spot quality.

14.
Sci Total Environ ; 512-513: 43-54, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25613769

RESUMO

Septic-system discharges can be an important source of micropollutants (including pharmaceuticals and endocrine active compounds) to adjacent groundwater and surface water systems. Groundwater samples were collected from well networks tapping glacial till in New England (NE) and sandy surficial aquifer New York (NY) during one sampling round in 2011. The NE network assesses the effect of a single large septic system that receives discharge from an extended health care facility for the elderly. The NY network assesses the effect of many small septic systems used seasonally on a densely populated portion of Fire Island. The data collected from these two networks indicate that hydrogeologic and demographic factors affect micropollutant concentrations in these systems. The highest micropollutant concentrations from the NE network were present in samples collected from below the leach beds and in a well downgradient of the leach beds. Total concentrations for personal care/domestic use compounds, pharmaceutical compounds and plasticizer compounds generally ranged from 1 to over 20 µg/L in the NE network samples. High tris(2-butoxyethyl phosphate) plasticizer concentrations in wells beneath and downgradient of the leach beds (>20 µg/L) may reflect the presence of this compound in cleaning agents at the extended health-care facility. The highest micropollutant concentrations for the NY network were present in the shoreline wells and reflect groundwater that is most affected by septic system discharges. One of the shoreline wells had personal care/domestic use, pharmaceutical, and plasticizer concentrations ranging from 0.4 to 5.7 µg/L. Estradiol equivalency quotient concentrations were also highest in a shoreline well sample (3.1 ng/L). Most micropollutant concentrations increase with increasing specific conductance and total nitrogen concentrations for shoreline well samples. These findings suggest that septic systems serving institutional settings and densely populated areas in coastal settings may be locally important sources of micropollutants to adjacent aquifer and marine systems.


Assuntos
Água Subterrânea/química , Hormônios/análise , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , New England , New York , Eliminação de Resíduos Líquidos , Poços de Água
15.
Br J Radiol ; 87(1037): 20130614, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24689842

RESUMO

OBJECTIVE: Eye tracking in three dimensions is novel, but established descriptors derived from two-dimensional (2D) studies are not transferable. We aimed to develop metrics suitable for statistical comparison of eye-tracking data obtained from readers of three-dimensional (3D) "virtual" medical imaging, using CT colonography (CTC) as a typical example. METHODS: Ten experienced radiologists were eye tracked while observing eight 3D endoluminal CTC videos. Subsequently, we developed metrics that described their visual search patterns based on concepts derived from 2D gaze studies. Statistical methods were developed to allow analysis of the metrics. RESULTS: Eye tracking was possible for all readers. Visual dwell on the moving region of interest (ROI) was defined as pursuit of the moving object across multiple frames. Using this concept of pursuit, five categories of metrics were defined that allowed characterization of reader gaze behaviour. These were time to first pursuit, identification and assessment time, pursuit duration, ROI size and pursuit frequency. Additional subcategories allowed us to further characterize visual search between readers in the test population. CONCLUSION: We propose metrics for the characterization of visual search of 3D moving medical images. These metrics can be used to compare readers' visual search patterns and provide a reproducible framework for the analysis of gaze tracking in the 3D environment. ADVANCES IN KNOWLEDGE: This article describes a novel set of metrics that can be used to describe gaze behaviour when eye tracking readers during interpretation of 3D medical images. These metrics build on those established for 2D eye tracking and are applicable to increasingly common 3D medical image displays.


Assuntos
Competência Clínica , Colonografia Tomográfica Computadorizada , Movimentos Oculares , Imageamento Tridimensional , Erros de Diagnóstico , Humanos , Interpretação de Imagem Radiográfica Assistida por Computador , Radiologia , Gravação em Vídeo
16.
J Ethnopharmacol ; 152(2): 227-42, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24463158

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pancreatic cancer is a devastating cancer that presents late, is rapidly progressive and has current therapeutics with only limited efficacy. Bioactive compounds are ubiquitously present in fruits and numerous studies in vitro are addressing the activity of these compounds against pancreatic cancer, thus studies of specific bioactive compounds could lead to new anti-pancreatic cancer strategies. Australian native fruits have been used as foods and medicines by Australian Aboriginals for thousands of years, and preliminary studies have found these fruits to contain rich and diversified bioactive components with high antioxidant activity. Thus, Australian native fruits may possess key components for preventing or delaying the onset of tumorigenesis, or for the treatment of existing cancers, including pancreatic cancer. MATERIALS AND METHODS: Numerous databases including PubMed, SciFinder, Web of Knowledge, Scopus, and Sciencedirect were analysed for correlations between bioactive components from fruits and pancreatic cancer, as well as studies concerning Australian native fruits. RESULTS: In this review, we comprehensively highlight the proposed mechanisms of action of fruit bioactives as anti-cancer agents, update the potential anti-pancreatic cancer activity of various major classes of bioactive compounds derived from fruits, and discuss the existence of bioactive compounds identified from a selection Australian native fruits for future studies. CONCLUSION: Bioactive compounds derived from fruits possess the potential for the discovery of new anti-pancreatic cancer strategies. Further, Australian native fruits are rich in polyphenols including some flora that contain unique phenolic compounds, thereby warranting further investigations into their anti-cancer properties.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Fenóis/farmacologia , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Austrália , Frutas , Humanos , Medicina Tradicional , Neoplasias Pancreáticas/patologia , Fenóis/isolamento & purificação , Polifenóis/isolamento & purificação , Polifenóis/farmacologia
17.
Oncogene ; 33(7): 882-90, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-23396365

RESUMO

Metastatic neuroblastoma is an aggressive childhood cancer of neural crest origin. Stathmin, a microtubule destabilizing protein, is highly expressed in neuroblastoma although its functional role in this malignancy has not been addressed. Herein, we investigate stathmin's contribution to neuroblastoma tumor growth and metastasis. Small interfering RNA (siRNA)-mediated stathmin suppression in two independent neuroblastoma cell lines, BE(2)-C and SH-SY5Y, did not markedly influence cell proliferation, viability or anchorage-independent growth. In contrast, stathmin suppression significantly reduced cell migration and invasion in both the neuroblastoma cell lines. Stathmin suppression altered neuroblastoma cell morphology and this was associated with changes in the cytoskeleton, including increased tubulin polymer levels. Stathmin suppression also modulated phosphorylation of the actin-regulatory proteins, cofilin and myosin light chain (MLC). Treatment of stathmin-suppressed neuroblastoma cells with the ROCKI and ROCKII inhibitor, Y-27632, ablated MLC phosphorylation and returned the level of cofilin phosphorylation and cell invasion back to that of untreated control cells. ROCKII inhibition (H-1152) and siRNA suppression also reduced cofilin phosphorylation in stathmin-suppressed cells, indicating that ROCKII mediates stathmin's regulation of cofilin phosphorylation. This data demonstrates a link between stathmin and the regulation of cofilin and MLC phosphorylation via ROCK. To examine stathmin's role in neuroblastoma metastasis, stathmin short hairpin RNA (shRNA)\luciferase-expressing neuroblastoma cells were injected orthotopically into severe combined immunodeficiency-Beige mice, and tumor growth monitored by bioluminescent imaging. Stathmin suppression did not influence neuroblastoma cell engraftment or tumor growth. In contrast, stathmin suppression significantly reduced neuroblastoma lung metastases by 71% (P<0.008) compared with control. This is the first study to confirm a role for stathmin in hematogenous spread using a clinically relevant orthotopic cancer model, and has identified stathmin as an important contributor of cell invasion and metastasis in neuroblastoma.


Assuntos
Neoplasias Pulmonares/metabolismo , Neuroblastoma/metabolismo , Interferência de RNA , Estatmina/genética , Fatores de Despolimerização de Actina/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Forma Celular , Sobrevivência Celular , Citoesqueleto/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Camundongos , Invasividade Neoplásica , Transplante de Neoplasias , Neuroblastoma/genética , Neuroblastoma/secundário , Fosforilação , Processamento de Proteína Pós-Traducional , RNA Interferente Pequeno/genética , Estatmina/metabolismo , Carga Tumoral , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/metabolismo
18.
PLoS One ; 8(7): e69560, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23894503

RESUMO

BACKGROUND: Ethanol is a potent teratogen. Its adverse neural effects are partly mediated by disrupting fetal neurogenesis. The teratogenic process is poorly understood, and vulnerable neurogenic stages have not been identified. Identifying these is a prerequisite for therapeutic interventions to mitigate effects of teratogen exposures. METHODS: We used flow cytometry and qRT-PCR to screen fetal mouse-derived neurosphere cultures for ethanol-sensitive neural stem cell (NSC) subpopulations, to study NSC renewal and differentiation. The identity of vulnerable NSC populations was validated in vivo, using a maternal ethanol exposure model. Finally, the effect of ethanol exposure on the ability of vulnerable NSC subpopulations to integrate into the fetal neurogenic environment was assessed following ultrasound guided, adoptive transfer. RESULTS: Ethanol decreased NSC mRNAs for c-kit, Musashi-1and GFAP. The CD24(+) NSC population, specifically the CD24(+)CD15(+) double-positive subpopulation, was selectively decreased by ethanol. Maternal ethanol exposure also resulted in decreased fetal forebrain CD24 expression. Ethanol pre-exposed CD24(+) cells exhibited increased proliferation, and deficits in cell-autonomous and cue-directed neuronal differentiation, and following orthotopic transplantation into naïve fetuses, were unable to integrate into neurogenic niches. CD24(depleted) cells retained neurosphere regeneration capacity, but following ethanol exposure, generated increased numbers of CD24(+) cells relative to controls. CONCLUSIONS: Neuronal lineage committed CD24(+) cells exhibit specific vulnerability, and ethanol exposure persistently impairs this population's cell-autonomous differentiation capacity. CD24(+) cells may additionally serve as quorum sensors within neurogenic niches; their loss, leading to compensatory NSC activation, perhaps depleting renewal capacity. These data collectively advance a mechanistic hypothesis for teratogenesis leading to microencephaly.


Assuntos
Antígeno CD24/genética , Etanol/toxicidade , Feto/citologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/transplante , Transplante de Células-Tronco , Animais , Biomarcadores/metabolismo , Antígeno CD24/metabolismo , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Antígenos CD15/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Teratogênese/efeitos dos fármacos , Teratogênicos/toxicidade
19.
J Laryngol Otol ; 127 Suppl 1: S21-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23046849

RESUMO

AIM: To assess the clinical and radiological characteristics of the posterior prolongation of the cartilaginous nasal septum, an under-utilised source of autologous cartilage for nasal reconstruction. MATERIALS AND METHODS: Consecutive patients undergoing primary, external approach rhinoplasty were included. The septal cartilage was assessed intra-operatively prior to routine harvest. Cartilage use was recorded and post-operative cosmesis noted. Computed tomography scans from a separate patient group, with no septal surgery, were used to assess septal cartilage dimensions. RESULTS: Of the 25 rhinoplasty patients studied, 24 had harvestable septal cartilage, with a posterior prolongation mean length ± standard deviation of 24.3 ± 8.40 mm, mean height of 4.33 ± 0.34 mm and mean width of 1.1 ± 0.35 mm. The mean post-operative cosmesis score was +2.41 ± 0.71 at a mean follow up of 45 ± 8.7 weeks. All 25 radiology patients had visible posterior prolongations on computed tomography (mean length, 18.1 ± 5.1 mm; mean height, 4.2 ± 1.1 mm; mean width 1.5 ± 0.63 mm). CONCLUSION: Harvesting of the posterior prolongation would increase by 25 per cent the cartilage area available for autologous grafts. Endoscopic guidance aids this process. Cartilage is most commonly used for overlay grafts, with good cosmesis. The posterior prolongation is demonstrated on computed tomography, although dimensions may be underestimated.


Assuntos
Cartilagens Nasais/transplante , Septo Nasal/cirurgia , Rinoplastia/métodos , Adolescente , Adulto , Idoso , Endoscopia , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Cartilagens Nasais/anatomia & histologia , Cartilagens Nasais/diagnóstico por imagem , Septo Nasal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
20.
Opt Lett ; 37(12): 2175-7, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22739846

RESUMO

We report on the first demonstration of a diode-pumped, gas cooled, cryogenic multislab Yb:YAG amplifier. The performance was characterized over a temperature range from 88 to 175 K. A maximum small-signal single-pass longitudinal gain of 11.0 was measured at 88 K. When amplifying nanosecond pulses, recorded output energies were 10.1 J at 1 Hz in a four-pass extraction geometry and 6.4 J at 10 Hz in a three-pass setup, corresponding to optical to optical conversion efficiencies of 21% and 16%, respectively. To our knowledge, this represents the highest pulse energy so far obtained from a cryo-cooled Yb-laser and the highest efficiency from a multijoule diode pumped solid-state laser system.

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