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1.
Eur J Pain ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38348557

RESUMO

BACKGROUND: Acceptance and Commitment Therapy (ACT) is a type of Cognitive Behavioural Therapy, which has demonstrated positive outcomes in individuals with chronic pain. The purpose of this study was to compare the effect of an 8-week programme combining Exercise with Acceptance and Commitment Therapy (ExACT) with a standalone supervised exercise programme at 1-year follow-up. METHODS: One hundred and seventy-five people with chronic pain were randomly assigned to ExACT or supervised exercise only. The primary outcome was pain interference measured with the Brief Pain Inventory-Interference Scale. Secondary and treatment process outcomes included pain severity, depression, anxiety, pain catastrophizing, pain self-efficacy, fear avoidance, pain acceptance, committed action, healthcare utilization, patient satisfaction, and global impression of change. Estimates of treatment effects at 1-year follow-up were based on intention-to-treat analyses, implemented using a linear mixed-effects model. RESULTS: Eighty-three participants (47.4%) returned the outcome measures at 1-year follow-up. No significant difference was observed between the groups for the primary outcome, pain interference. There was a statistically significant difference between the groups, in favour of ExACT for pain catastrophizing. Within group improvements that were observed within both groups at earlier timepoints were maintained at 1-year follow-up for many of the secondary and treatment process outcomes. ExACT group participants reported higher levels of satisfaction with treatment and global perceived change. CONCLUSIONS: The study results showed no significant difference between the two groups for the primary outcome pain interference at 1-year follow-up. Future research could investigate factors that may predict and optimize outcomes from these types of intervention for people living with chronic pain. SIGNIFICANCE: Few previous randomized controlled trials investigating ACT for chronic pain have included long-term follow-up. This study found that Exercise combined with ACT was not superior to supervised exercise alone for reducing pain interference at 1-year follow-up. Further research is necessary to identify key processes of therapeutic change and to explore how interventions may be modified to enhance clinical outcomes for people with chronic pain.

2.
Environ Sci Technol ; 58(5): 2271-2281, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38270974

RESUMO

To mitigate methane emission from urban natural gas distribution systems, it is crucial to understand local leak rates and occurrence rates. To explore urban methane emissions in cities outside the U.S., where significant emissions were found previously, mobile measurements were performed in 12 cities across eight countries. The surveyed cities range from medium size, like Groningen, NL, to large size, like Toronto, CA, and London, UK. Furthermore, this survey spanned across European regions from Barcelona, ES, to Bucharest, RO. The joint analysis of all data allows us to focus on general emission behavior for cities with different infrastructure and environmental conditions. We find that all cities have a spectrum of small, medium, and large methane sources in their domain. The emission rates found follow a heavy-tailed distribution, and the top 10% of emitters account for 60-80% of total emissions, which implies that strategic repair planning could help reduce emissions quickly. Furthermore, we compare our findings with inventory estimates for urban natural gas-related methane emissions from this sector in Europe. While cities with larger reported emissions were found to generally also have larger observed emissions, we find clear discrepancies between observation-based and inventory-based emission estimates for our 12 cities.


Assuntos
Poluentes Atmosféricos , Gás Natural , Cidades , Gás Natural/análise , Metano/análise , Poluentes Atmosféricos/análise , Londres
3.
Ir J Psychol Med ; 40(3): 402-410, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36782404

RESUMO

BACKGROUND: Global healthcare systems have been particularly impacted by the COVID-19 pandemic. Healthcare workers (HCWs) are widely reported to have experienced increased levels of baseline psychological distress relative to the general population, and the COVID-19 pandemic may have had an additive effect. However, previous studies are typically restricted to physicians and nurses with limited data available on hospital HCWs. We aimed to conduct a cross-sectional, psychological evaluation of Irish HCWs during COVID-19. METHODS: HCWs across five adult acute level-4 Dublin-based hospitals completed an online survey of wellbeing and COVID-19 experience. RESULTS: There were 1898 HCWs who commenced the survey representing 10% of the total employee base. The sample comprised nurses (33%), doctors (21%), Health and Social Care Professionals (HSCPs) (24%) and 'Other' disciplines (22%), and 81% identified as female. Clinical levels of depression, anxiety and PTSD symptoms were endorsed by 31%, 34% and 28% of respondents, respectively. Professional grouping effects included: nurses reporting significantly greater levels of COVID-19 exposure, infection, COVID-fear, moral injury, and post-traumatic distress; HSCPs were significantly less likely to report mood dysfunction. In terms of gender, males were significantly less likely to report negative pandemic experiences, low resilience, and significantly more likely to endorse 'minimal' depression, anxiety, and traumatic distress. Logistic regression modelling revealed mental health outcomes (depression, anxiety and PTSD symptoms) were associated with increased frontline exposure, fewer career years' experience, elevated pre-pandemic stress, and female gender. DISCUSSION: To our knowledge, this is the largest evaluation of psychological wellbeing amongst HCWs in acute hospitals in the Dublin region. Our findings have implications for healthcare workforce wellbeing and future service delivery.


Assuntos
COVID-19 , Pandemias , Adulto , Masculino , Humanos , Feminino , Estudos Transversais , Pessoal de Saúde , Hospitais , Avaliação de Resultados em Cuidados de Saúde
4.
Ann Biomed Eng ; 49(10): 2886-2900, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34184145

RESUMO

Impacts to the back of the head due to rearward falls, also referred to as "backfall" events, represent a common source of TBI for athletes and soldiers. A new experimental apparatus is described for replicating the linear and rotational kinematics of the head during backfall events. An anthropomorphic test device (ATD) with a head-borne sensor suite was configured to fall backwards from a standing height, inducing contact between the rear of the head and a ground surface simulant. A pivoting swing arm and release strap were used to generate consistent and realistic head kinematics. Backfall experiments were performed with the ATD fitted with an American football helmet and the resulting linear and rotational head kinematics, as well as calculated injury metrics, compared favorably with those of football players undergoing similar impacts during games or play reconstructions. This test method complements existing blunt impact helmet performance experiments, such as drop tower and pneumatic ram test methods, which may not be able to fully reproduce head-neck-torso kinematics during a backfall event.


Assuntos
Acidentes por Quedas , Traumatismos em Atletas/fisiopatologia , Traumatismos Craniocerebrais/fisiopatologia , Futebol Americano/lesões , Modelos Biológicos , Telemetria/instrumentação , Dispositivos Eletrônicos Vestíveis , Aceleração , Fenômenos Biomecânicos , Cabeça , Dispositivos de Proteção da Cabeça , Humanos , Masculino , Protetores Bucais , Rotação
5.
6.
J Liposome Res ; 30(2): 136-149, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31010367

RESUMO

Caucasian population groups have a higher propensity to develop skin cancer, and associated clinical interventions often present substantial financial burden on healthcare services. Conventional treatments are often not suitable for all patient groups as a result of poor efficacy and toxicity profiles. The primary objective of this study was to develop a deformable liposomal formulation, the properties of which being dictated by the surfactant Tween 20, for the dermal cellular delivery of epigallocatechin gallatein (EGCG), a compound possessing antineoplastic properties. The results demonstrated a significant (p ≤ 0.05) decrease in liposome deformability index (74 ± 8 to 37 ± 7) as Tween 20 loading increased from 0 to 10% w/w, indicating an increase in elasticity. EGCG release over 24-h demonstrated Tween 20 incorporation directly increased release from 13.7% ± 1.1% to 94.4% ± 4.9% (for 0 and 10% w/w Tween 20 respectively). Finally, we demonstrated DilC-loaded deformable liposomes were localized intracellularly within human dermal fibroblast and keratinocyte cells within 2 h. Thus, it was evident that deformable liposomes may aid drug penetration into dermal cells and would be useful in developing a controlled-release formulation.


Assuntos
Antineoplásicos/farmacologia , Catequina/análogos & derivados , Neoplasias Cutâneas/tratamento farmacológico , Antineoplásicos/química , Catequina/química , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipossomos , Estrutura Molecular , Tamanho da Partícula , Polissorbatos/química , Absorção Cutânea/efeitos dos fármacos , Neoplasias Cutâneas/patologia , Relação Estrutura-Atividade , Propriedades de Superfície , Tensoativos/química
7.
Dis Aquat Organ ; 136(2): 157-162, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621648

RESUMO

The prevalence of Ichthyophonus infection in Pacific herring Clupea pallasii was spatially heterogeneous in the southern Salish Sea, Washington State, USA. Over the course of 13 mo, 2232 Pacific herring were sampled from 38 midwater trawls throughout the region. Fork length was positively correlated with Ichthyophonus infection at all sites. After controlling for the positive relationship between host size and Ichthyophonus infection, the probability of infection was approximately 6-fold higher in North Hood Canal than in Puget Sound and the northern Straits (12 vs. 2% predicted probability for a 100 mm fish and 30 vs. 7% predicted probability for a 180 mm fish). Temporal changes in Ichthyophonus infection probability were explained by seasonal differences in fish length, owing to Pacific herring life history and movement patterns. Reasons for the spatial heterogeneity remain uncertain but may be associated with density-dependent factors inherent to the boom-bust cycles that commonly occur in clupeid populations.


Assuntos
Doenças dos Peixes , Infecções por Mesomycetozoea , Mesomycetozoea , Animais , Peixes , Oceanos e Mares , Washington
8.
J Thromb Haemost ; 17(2): 345-349, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30552749

RESUMO

Essentials Low-molecular-weight heparin (LMWH) is used to prevent venous thromboembolism (VTE) in pregnancy. We evaluated the association between LMWH and large for gestational age (LGA) infants. We found no significant associations between LMWH use and LGA. LMWH does not appear to increase the risk for the delivery of an LGA infant. SUMMARY: Background Low-molecular-weight heparin (LMWH), an anticoagulant, is the recommended drug for thromboprophylaxis and treatment of venous thromboembolism (VTE) in pregnancy. During pregnancy, LMWH is routinely prescribed to mothers with an increased risk of VTE or with a history of thrombosis. Although clinical reports of larger offspring born to women administered LMWH have been noted, no studies to date have evaluated or associated the use of LMWH and large for gestational age (LGA) infants. Objectives To determine whether there is an association between LMWH usage in mothers and the prevalence of LGA. Patients/Methods We performed an analysis of the Ottawa and Kingston (OaK) Birth Cohort and report characteristics of LMWH and association LGA (> 10%ile). We used coarsened exact matching (CEM) methods to account for bias and confounding. Results A total of 7519 women from the OaK Birth Cohort were included; 59 were administered LMWH during pregnancy (0.78%). Mothers prescribed LMWH had significantly greater BMI (P = 0.0001), age (P = 0.0001) and parity (P = 0.02). Gestational length was shorter among women administered LMWH compared to those without treatment (37.7 ± 2.0 vs. 39.2 ± 2.0, P < 0.0001), an iatrogenic finding. The odds ratio of an LGA delivery among women administered LMWH was 1.02 (95% confidence interval [CI], 0.48-2.16; P = 0.96) in unadjusted analyses and was 1.15 (95% CI, 0.49-2.71) in the matched sample adjusted for maternal age, BMI and gestational age. Conclusions These results, although exploratory, provide indirect evidence of no increased risk of LGA infants among women prescribed LMWH.


Assuntos
Anticoagulantes/efeitos adversos , Macrossomia Fetal/induzido quimicamente , Heparina de Baixo Peso Molecular/efeitos adversos , Complicações Cardiovasculares na Gravidez/prevenção & controle , Tromboembolia Venosa/prevenção & controle , Adulto , Anticoagulantes/administração & dosagem , Feminino , Macrossomia Fetal/diagnóstico , Macrossomia Fetal/epidemiologia , Idade Gestacional , Heparina de Baixo Peso Molecular/administração & dosagem , Humanos , Ontário/epidemiologia , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/epidemiologia , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Adulto Jovem
9.
Sci Rep ; 7(1): 4854, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28687748

RESUMO

A thorough understanding of methane sources is necessary to accomplish methane reduction targets. Urban environments, where a large variety of methane sources coexist, are one of the most complex areas to investigate. Methane sources are characterised by specific δ13C-CH4 signatures, so high precision stable isotope analysis of atmospheric methane can be used to give a better understanding of urban sources and their partition in a source mix. Diurnal measurements of methane and carbon dioxide mole fraction, and isotopic values at King's College London, enabled assessment of the isotopic signal of the source mix in central London. Surveys with a mobile measurement system in the London region were also carried out for detection of methane plumes at near ground level, in order to evaluate the spatial allocation of sources suggested by the inventories. The measured isotopic signal in central London (-45.7 ±0.5‰) was more than 2‰ higher than the isotopic value calculated using emission inventories and updated δ13C-CH4 signatures. Besides, during the mobile surveys, many gas leaks were identified that are not included in the inventories. This suggests that a revision of the source distribution given by the emission inventories is needed.

10.
Eur J Vasc Endovasc Surg ; 52(4): 518-525, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27595522

RESUMO

OBJECTIVE/BACKGROUND: Women are known to have a higher rate of postoperative complications and mortality following open abdominal aortic aneurysm (AAA) repair. It is less clear whether this remains true of endovascular aneurysm repair (EVAR). This study examines the association between sex and hospital length of stay (LoS), readmission rates, and mortality following elective EVAR in the population of England between April 2006 and March 2015. METHODS: Retrospective analysis of Hospital Episode Statistics (HES) was performed, including regression analysis of potential factors that may affect the primary outcomes (age, sex, deprivation, comorbidities and Trust volume). RESULTS: In total, 20,780 EVARs were performed in the time period, 11.2% (n = 2,304) on women. The women were older (78 years [interquartile range {IQR} 74-82 years] vs. 76 years [IQR 70-80 years]; p < .001) and had a longer LoS (5 days [IQR 3-8 days] vs. 4 days [IQR 3-6 days]; p < .001). Women also had a higher readmission rate and mortality rate at both 30 days and 1 year. Following multivariate logistic regression, being female remained significantly related to poor outcome on all outcomes: LoS (odds ratio [OR] 1.86, 95% confidence interval [CI] 1.69-2.05), 30-day readmission (OR 1.23, 95% CI 1.09-1.40), 1-year readmission (OR 1.16, 95% CI 1.06-1.28); 30-day mortality (OR 1.54, 95% CI 1.15-2.07), 1-year mortality (OR 1.24, 95% CI 1.06-1.45). Advancing age and increased comorbidity score were significantly related to longer LoS, higher readmission rates, and higher mortality. Deprivation score was associated with LoS and 1-year readmission rate but not with 30-day readmission and with increased mortality. Higher-volume Trusts (>50 EVARs per year) had higher readmission rates and 1-year mortality. CONCLUSION: These population-based data show that, following EVAR, women have a longer LoS and higher readmission and mortality than men. This reflects the same disparity in outcomes that is found in open AAA repair. Further work to clarify the cause of this is needed.


Assuntos
Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Implante de Prótese Vascular/mortalidade , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Complicações Pós-Operatórias , Medição de Risco , Caracteres Sexuais , Resultado do Tratamento
11.
J Viral Hepat ; 23(8): 584-95, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27167497

RESUMO

Chronic hepatitis C is associated with health-related quality of life and cognitive impairments, even in mild disease. Recent evidence demonstrating hepatitis C virus (HCV) neurotropism has strengthened a neuropathophysiological hypothesis. However, sample heterogeneity confounds study outcomes. A uniquely homogeneous cohort of Irish women, following an iatrogenic HCV outbreak, offers a rare opportunity to control for HCV chronicity and the virus' purported impact on quality of life and cognition. A multi site, three-group, cross-sectional design was employed. Noncirrhotic, iatrogenically infected women, developing either acute or chronic infection, were recruited from prospective tertiary-care liver clinics and the community. Well-matched healthy controls were also recruited. All participants completed a psychosocial survey and were invited to undergo a comprehensive neuropsychological test battery. Significantly distressed psychosocial symptom profiles were observed in those with an iatrogenic HCV exposure history, which was independent of viral chronicity. Chronic and cleared HCV cohorts were not differentiated from each other. Two distinct subgroups, demarcated along 'impaired' vs 'nonimpaired' quality-of-life reports, were clearly identified and logistic regression analysis identified depressed mood and cognitive fatigue, rather than viral status, as statistically significant predictors of group membership. Compared with matched controls, significant cognitive impairments were not observed in either HCV cohort. Our findings provide strong evidence of nonviral factors accounting for quality of life impairment in chronic HCV and they also appear to question existing reports of cognitive dysfunction in mild disease. Depressed mood and cognitive fatigue appear to be critical psychosocial mediators of reduced quality-of-life and we hypothesize that metabolite abnormalities reported in HCV samples may also be confounded by these factors, given the associated literature.


Assuntos
Disfunção Cognitiva , Hepatite C Crônica/complicações , Hepatite C Crônica/psicologia , Doença Iatrogênica , Idoso , Estudos Transversais , Feminino , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Carência Psicossocial , Qualidade de Vida
12.
Sci Rep ; 6: 25661, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27210416

RESUMO

Atmospheric CO at Egham in SE England has shown a marked and progressive decline since 1997, following adoption of strict controls on emissions. The Egham site is uniquely positioned to allow both assessment and comparison of 'clean Atlantic background' air and CO-enriched air downwind from the London conurbation. The decline is strongest (approximately 50 ppb per year) in the 1997-2003 period but continues post 2003. A 'local CO increment' can be identified as the residual after subtraction of contemporary background Atlantic CO mixing ratios from measured values at Egham. This increment, which is primarily from regional sources (during anticyclonic or northerly winds) or from the European continent (with easterly air mass origins), has significant seasonality, but overall has declined steadily since 1997. On many days of the year CO measured at Egham is now not far above Atlantic background levels measured at Mace Head (Ireland). The results are consistent with MOPITT satellite observations and 'bottom-up' inventory results. Comparison with urban and regional background CO mixing ratios in Hong Kong demonstrates the importance of regional, as opposed to local reduction of CO emission. The Egham record implies that controls on emissions subsequent to legislation have been extremely successful in the UK.

13.
J Geophys Res Atmos ; 121(23): 14257-14270, 2016 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31413935

RESUMO

A stratified air mass enriched in methane (CH4) was sampled at ~600 m to ~2000 m altitude, between the north coast of Norway and Svalbard as part of the Methane in the Arctic: Measurements and Modelling campaign on board the UK's BAe-146-301 Atmospheric Research Aircraft. The approach used here, which combines interpretation of multiple tracers with transport modeling, enables better understanding of the emission sources that contribute to the background mixing ratios of CH4 in the Arctic. Importantly, it allows constraints to be placed on the location and isotopic bulk signature of the emission source(s). Measurements of δ13C in CH4 in whole air samples taken while traversing the air mass identified that the source(s) had a strongly depleted bulk δ13C CH4 isotopic signature of -70 (±2.1)‰. Combined Numerical Atmospheric-dispersion Modeling Environment and inventory analysis indicates that the air mass was recently in the planetary boundary layer over northwest Russia and the Barents Sea, with the likely dominant source of methane being from wetlands in that region.

14.
Mutat Res ; 745(1-2): 28-37, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22178868

RESUMO

Carbon nanotubes were among the earliest products of nanotechnology and have many potential applications in medicine, electronics, and manufacturing. The low density, small size, and biological persistence of carbon nanotubes create challenges for exposure control and monitoring and make respiratory exposures to workers likely. We have previously shown mitotic spindle aberrations in cultured primary and immortalized human airway epithelial cells exposed to 24, 48 and 96 µg/cm(2) single-walled carbon nanotubes (SWCNT). To investigate mitotic spindle aberrations at concentrations anticipated in exposed workers, primary and immortalized human airway epithelial cells were exposed to SWCNT for 24-72 h at doses equivalent to 20 weeks of exposure at the Permissible Exposure Limit for particulates not otherwise regulated. We have now demonstrated fragmented centrosomes, disrupted mitotic spindles and aneuploid chromosome number at those doses. The data further demonstrated multipolar mitotic spindles comprised 95% of the disrupted mitoses. The increased multipolar mitotic spindles were associated with an increased number of cells in the G2 phase of mitosis, indicating a mitotic checkpoint response. Nanotubes were observed in association with mitotic spindle microtubules, the centrosomes and condensed chromatin in cells exposed to 0.024, 0.24, 2.4 and 24 µg/cm(2) SWCNT. Three-dimensional reconstructions showed carbon nanotubes within the centrosome structure. The lower doses did not cause cytotoxicity or reduction in colony formation after 24h; however, after three days, significant cytotoxicity was observed in the SWCNT-exposed cells. Colony formation assays showed an increased proliferation seven days after exposure. Our results show significant disruption of the mitotic spindle by SWCNT at occupationally relevant doses. The increased proliferation that was observed in carbon nanotube-exposed cells indicates a greater potential to pass the genetic damage to daughter cells. Disruption of the centrosome is common in many solid tumors including lung cancer. The resulting aneuploidy is an early event in the progression of many cancers, suggesting that it may play a role in both tumorigenesis and tumor progression. These results suggest caution should be used in the handling and processing of carbon nanotubes.


Assuntos
Mitose/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Mucosa Respiratória/efeitos dos fármacos , Fuso Acromático/efeitos dos fármacos , Aneuploidia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Mucosa Respiratória/citologia
15.
Anal Chem ; 83(7): 2740-7, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21405068

RESUMO

Capillary electrophoresis separations of glycans labeled with 1-aminopyrene-3,6,8-trisulfonic acid were achieved with separation efficiencies ranging from 480,000 to 640,000 theoretical plates in a 60.2 cm, 25 µm inner diameter fused silica capillary. Under these separation conditions, the coefficient of variation in peak area is 10%, and if labeling efficiency is estimated at 100%, the limit of detection is 15 fM. The capillary electrophoresis method incorporated phospholipid additives to enhance the separation of glycans with slight differences in hydrodynamic volume. In addition, the phospholipid additives supported the integration of the lectin concanavalin A as well as the enzymes α1-2,3 mannosidase or ß1-4 galactosidase to provide structural and compositional information about the glycans subject to separation. The use of in-capillary cleavage of terminal glycan residues with exoglycosidases offers a number of advantages over benchtop enzymatic sequencing, including reduced consumption of analyte, as well as enzyme. These methods were used to evaluate glycans derived from the glycoproteins α1-acid glycoprotein, fetuin, and ribonuclease B, as well as from glycoproteins collected from MCF7 cells.


Assuntos
Concanavalina A/metabolismo , Eletroforese Capilar/métodos , Glicosídeo Hidrolases/metabolismo , Fosfolipídeos/metabolismo , Polissacarídeos/isolamento & purificação , Polissacarídeos/metabolismo , Linhagem Celular Tumoral , Eletricidade , Eletroforese Capilar/normas , Humanos , Injeções , Manosidases/metabolismo , Lectinas de Plantas/metabolismo , Padrões de Referência
16.
Toxicol Appl Pharmacol ; 252(1): 1-10, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21310169

RESUMO

The production of carbon nanofibers and nanotubes (CNF/CNT) and their composite products is increasing globally. CNF are generating great interest in industrial sectors such as energy production and electronics, where alternative materials may have limited performance or are produced at a much higher cost. However, despite the increasing industrial use of carbon nanofibers, information on their potential adverse health effects is limited. In the current study, we examine the cytotoxic and genotoxic potential of carbon-based nanofibers (Pyrograf®-III) and compare this material with the effects of asbestos fibers (crocidolite) or single-walled carbon nanotubes (SWCNT). The genotoxic effects in the lung fibroblast (V79) cell line were examined using two complementary assays: the comet assay and micronucleus (MN) test. In addition, we utilized fluorescence in situ hybridization to detect the chromatin pan-centromeric signals within the MN indicating their origin by aneugenic (chromosomal malsegregation) or clastogenic (chromosome breakage) mechanisms. Cytotoxicity tests revealed a concentration- and time-dependent loss of V79 cell viability after exposure to all tested materials in the following sequence: asbestos>CNF>SWCNT. Additionally, cellular uptake and generation of oxygen radicals was seen in the murine RAW264.7 macrophages following exposure to CNF or asbestos but not after administration of SWCNT. DNA damage and MN induction were found after exposure to all tested materials with the strongest effect seen for CNF. Finally, we demonstrated that CNF induced predominantly centromere-positive MN in primary human small airway epithelial cells (SAEC) indicating aneugenic events. Further investigations are warranted to elucidate the possible mechanisms involved in CNF-induced genotoxicity.


Assuntos
Amianto/toxicidade , Sobrevivência Celular/genética , Fibroblastos/fisiologia , Nanotubos de Carbono/toxicidade , Animais , Amianto/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cricetinae , Cricetulus , Fibroblastos/efeitos dos fármacos , Humanos , Testes de Mutagenicidade/métodos , Nanotubos de Carbono/efeitos adversos
17.
J Dairy Sci ; 93(7): 2857-62, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20630202

RESUMO

Most infant formulas use vegetable oils in place of milk fat to provide an overall fatty acid profile similar to that of breast milk. Vegetable oils have 5 to 20% saturated fatty acids in the sn-2 position of triglycerides unless they are modified by interesterification. Interesterification is increasingly used for the fat for infant formulas to raise the level of saturated fatty acids in the sn-2 position to 40 to 60%. The objective of this study was to verify an alternative approach to providing the appropriate fatty acid profile, including in the sn-2 position, for a goat infant formula. In this method, 55% of total fat was made from goat milk fat and 45% from a mixture of unmodified high oleic sunflower, canola, and sunflower oils in a ratio of 44:30:26. The fatty acid profile was measured by gas-liquid chromatography and the relative percentage of fatty acids in the sn-2 position of triglycerides was measured via partial deacylation with Grignard reagent using trimethylsilyl derivatives of monoacylglycerols. Mixing goat milk fat with vegetable oils produced a formula with a profile of essential fatty acids and a ratio of linoleic:alpha-linolenic fatty acids within the required interval of 5 to 15:1 recommended for infant formula. The proportion of palmitic acid in the sn-2 position was 31%.


Assuntos
Ácidos Graxos/química , Fórmulas Infantis/química , Triglicerídeos/química , Animais , Bovinos , Gorduras/análise , Ácidos Graxos/análise , Cabras , Humanos , Lactente , Leite/química
18.
Mol Ecol ; 19(13): 2739-53, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20546131

RESUMO

Local adaptation is considered to be the result of fitness trade-offs for particular phenotypes across different habitats. However, it is unclear whether such phenotypic trade-offs exist at the level of individual genetic loci. Local adaptation could arise from trade-offs of alternative alleles at individual loci or by complementary sets of loci with different fitness effects of alleles in one habitat but selective neutrality in the alternative habitat. To evaluate the genome-wide basis of local adaptation, we performed a field-based quantitative trait locus (QTL) mapping experiment on recombinant inbred lines (RILs) created from coastal perennial and inland annual races of the yellow monkeyflower (Mimulus guttatus) grown reciprocally in native parental habitats. Overall, we detected 19 QTLs affecting one or more of 16 traits measured in two environments, most of small effect. We identified 15 additional QTL effects at two previously identified candidate QTLs [DIVERGENCE (DIV)]. Significant QTL by environment interactions were detected at the DIV loci, which was largely attributable to genotypic differences at a single field site. We found no detectable evidence for trade-offs for any one component of fitness, although DIV2 showed a trade-off involving different fitness traits between sites, suggesting that local adaptation is largely controlled by non-overlapping loci. This is surprising for an outcrosser, implying that reduced gene flow prevents the evolution of individuals adapted to multiple environments. We also determined that native genotypes were not uniformly adaptive, possibly reflecting fixed mutational load in one of the populations.


Assuntos
Adaptação Fisiológica/genética , Fluxo Gênico , Mimulus/genética , Locos de Características Quantitativas , Alelos , Mapeamento Cromossômico , DNA de Plantas/genética , Meio Ambiente , Evolução Molecular , Aptidão Genética , Ligação Genética , Genótipo , Oregon , Análise de Sequência de DNA
19.
J Viral Hepat ; 17(5): 352-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19758275

RESUMO

Neurocognitive dysfunction has been reported in individuals with chronic hepatitis C (CHC) infection, but HCV populations investigated have often included participants with numerous potential confounding comorbidities. This pilot study sought to investigate functional capacity and neurocognitive function in a homogeneous state-infected HCV population with histologically defined mild liver disease, free from the comorbid factors typically associated with HCV populations. A further aim was to examine cognitive function in a treatment naive population with a similar history of iatrogenic HCV exposure and spontaneous viral clearance. A convenience sample of 29 women, all of whom were carefully screened to exclude relevant comorbidities, was recruited to the study. Twenty women with a history of iatrogenic HCV exposure were recruited from prospective specialist tertiary care liver clinics. A comparison group of healthy controls (n = 9) was also assessed. Study participants underwent mood, health-related quality of life and neuropsychological assessment. CHC patients reported significantly higher levels of cognitive fatigue than healthy controls (F = 3.4, P = 0.04). On cognitive testing, CHC patients showed impairments compared with healthy controls on estimates of general memory [F(2,25) = 4.1, P = 0.03, partial eta squared = 0.25], delayed auditory recognition [F(2,25) = 4.2, P = 0.03, partial eta squared= 0.22] and sustained attention [F(2,25) = 3.6, P = 0.04, partial eta squared = 0.22]. Increased cognitive fatigue only correlated with delayed auditory memory recall ability (r = 0.724, P = 0.006). In conclusion, these findings appear to support the presence of neurocognitive abnormalities in an iatrogenically infected, homogeneous female HCV population who were carefully screened to eliminate other factors affecting neurocognitive test performance and may indicate underlying neurophysiological causative mechanisms.


Assuntos
Transtornos Cognitivos/diagnóstico , Hepatite C/complicações , Hepatite C/psicologia , Doença Iatrogênica , Adulto , Afeto , Feminino , Humanos , Irlanda , Pessoa de Meia-Idade , Testes Neuropsicológicos , Qualidade de Vida/psicologia
20.
Environ Mol Mutagen ; 50(8): 708-17, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19774611

RESUMO

Engineered carbon nanotubes are newly emerging manufactured particles with potential applications in electronics, computers, aerospace, and medicine. The low density and small size of these biologically persistent particles makes respiratory exposures to workers likely during the production or use of commercial products. The narrow diameter and great length of single-walled carbon nanotubes (SWCNT) suggest the potential to interact with critical biological structures. To examine the potential of nanotubes to induce genetic damage in normal lung cells, cultured primary and immortalized human airway epithelial cells were exposed to SWCNT or a positive control, vanadium pentoxide. After 24 hr of exposure to either SWCNT or vanadium pentoxide, fragmented centrosomes, multiple mitotic spindle poles, anaphase bridges, and aneuploid chromosome number were observed. Confocal microscopy demonstrated nanotubes within the nucleus that were in association with cellular and mitotic tubulin as well as the chromatin. Our results are the first to report disruption of the mitotic spindle by SWCNT. The nanotube bundles are similar to the size of microtubules that form the mitotic spindle and may be incorporated into the mitotic spindle apparatus.


Assuntos
Aneuploidia , Nanotubos de Carbono , Linhagem Celular Transformada , Humanos , Hibridização in Situ Fluorescente , Tamanho da Partícula
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