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1.
Glob Chang Biol ; 30(1): e17053, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273544

RESUMO

Soil is a huge carbon (C) reservoir, but where and how much extra C can be stored is unknown. Current methods to estimate the maximum amount of mineral-associated organic carbon (MAOC) stabilized in the fine fraction (clay + silt, < 20 µm $$ <20\;\upmu \mathrm{m} $$ ) fit through the MAOC versus clay + silt relationship, not their maxima, making their estimates more uncertain and unreliable. We need a function that 'envelopes' that relationship. Here, using 5089 observations, we estimated that the uppermost 30 cm of Australian soil holds 13 Gt (10-18 Gt) of MAOC. We then fitted frontier lines, by soil type, to the relationship between MAOC and the percentage of clay + silt to estimate the maximum amounts of MAOC that Australian soils could store in their current environments, and calculated the MAOC deficit, or C sequestration potential. We propagated the uncertainties from the frontier line fitting and mapped the estimates of these values over Australia using machine learning and kriging with external drift. The maps show regions where the soil is more in MAOC deficit and has greater sequestration potential. The modelling shows that the variation over the whole continent is determined mainly by climate, linked to vegetation and soil mineralogy. We find that the MAOC deficit in Australian soil is 40 Gt (25-60 Gt). The deficit in the vast rangelands is 20.84 Gt (13.97-29.70 Gt) and the deficit in cropping soil is 1.63 Gt (1.12-2.32 Gt). Management could increase C sequestration in these regions if the climate allowed it. Our findings provide new information on the C sequestration potential of Australian soils and highlight priority regions for soil management. Australia could benefit environmentally, socially and economically by unlocking even a tiny portion of its soil's C sequestration potential.


Assuntos
Carbono , Solo , Argila , Carbono/análise , Sequestro de Carbono , Austrália , Minerais
2.
Phys Rev Lett ; 130(9): 091801, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930908

RESUMO

The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ.

3.
Front Pharmacol ; 12: 679388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712131

RESUMO

Introduction: Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disease with a poor prognosis and increasing incidence. Pirfenidone and nintedanib are the only approved treatments for IPF but have limited efficacy and their mechanisms of action are poorly understood. Here we have examined the effects of pirfenidone and nintedanib in a human model of lung fibrogenesis, and compared these with the putative anti-fibrotic compounds Lipoxin A4 (LXA4), and senicapoc, a KCa3.1 ion channel blocker. Methods: Early fibrosis was induced in cultured human lung parenchyma using TGFß1 for 7 days, ± pirfenidone, nintedanib, or LXA4. Pro-fibrotic responses were examined by RT-PCR, immunohistochemistry and soluble collagen secretion. Results: Thirty six out of eighty four IPF and fibrosis-associated genes tested were significantly upregulated by TGFß1 in human lung parenchyma with a ≥0.5 log2FC (n = 32). Nintedanib (n = 13) reduced the mRNA expression of 14 fibrosis-associated genes including MMPs (MMP1,-4,-13,-14), integrin α2, CXCR4 and PDGFB, but upregulated α-smooth muscle actin (αSMA). Pirfenidone only reduced mRNA expression for MMP3 and -13. Senicapoc (n = 11) previously attenuated the expression of 28 fibrosis-associated genes, including αSMA, several growth factors, collagen type III, and αV/ß6 integrins. Pirfenidone and nintedanib significantly inhibited TGFß1-induced fibroblast proliferation within the tissue, but unlike senicapoc, neither pirfenidone nor nintedanib prevented increases in tissue αSMA expression. LXA4 was ineffective. Conclusions: Pirfenidone and nintedanib demonstrate modest anti-fibrotic effects and provide a benchmark for anti-fibrotic activity of new drugs in human lung tissue. Based on these data, we predict that the KCa3.1 blocker senicapoc will show greater benefit than either of these licensed drugs in IPF.

4.
Sci Total Environ ; 749: 142262, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33370926

RESUMO

The ecological restoration of ecosystem services and biodiversity is a key intervention used to reverse the impacts of anthropogenic activities such as mining. Assessment of the performance of restoration against completion criteria relies on biodiversity monitoring. However, monitoring usually overlooks soil microbial communities (SMC), despite increased awareness of their pivotal role in many ecological functions. Recent advances in cost, scalability and technology has led to DNA sequencing being considered as a cost-effective biological monitoring tool, particularly for otherwise difficult to survey groups such as microbes. However, such approaches for monitoring complex restoration sites such as post-mined landscapes have not yet been tested. Here we examine bacterial and fungal communities across chronosequences of mine site restoration at three locations in Western Australia to determine if there are consistent changes in SMC diversity, community composition and functional capacity. Although we detected directional changes in community composition indicative of microbial recovery, these were inconsistent between locations and microbial taxa (bacteria or fungi). Assessing functional diversity provided greater understanding of changes in site conditions and microbial recovery than could be determined through assessment of community composition alone. These results demonstrate that high-throughput amplicon sequencing of environmental DNA (eDNA) is an effective approach for monitoring the complex changes in SMC following restoration. Future monitoring of mine site restoration using eDNA should consider archiving samples to provide improved understanding of changes in communities over time. Expansion to include other biological groups (e.g. soil fauna) and substrates would also provide a more holistic understanding of biodiversity recovery.


Assuntos
Microbiota , Solo , Biodiversidade , Ecossistema , Sequenciamento de Nucleotídeos em Larga Escala , Microbiologia do Solo , Austrália Ocidental
5.
Plant Biol (Stuttg) ; 21(3): 458-469, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30098068

RESUMO

In degraded dryland systems, native plant community re-establishment following disturbance is almost exclusively carried out using seeds, but these efforts commonly fail. Much of this failure can be attributed to the limited understanding of seed dormancy and germination traits. We undertook a systematic classification of seed dormancy of 26 species of annual and perennial forbs and shrubs that represent key, dominant genera used in restoration of the Great Basin ecosystem in the western United States. We examined germination across a wide thermal profile to depict species-specific characteristics and assessed the potential of gibberellic acid (GA3 ) and karrikinolide (KAR1 ) to expand the thermal germination envelope of fresh seeds. Of the tested species, 81% produce seeds that are dormant at maturity. The largest proportion (62%) exhibited physiological (PD), followed by physical (PY, 8%), combinational (PY + PD, 8%) and morphophysiological (MPD, 4%) dormancy classes. The effects of chemical stimulants were temperature- and species-mediated. In general, mean germination across the thermal profile was improved by GA3 and KAR1 for 11 and five species, respectively. We detected a strong germination response to temperature in freshly collected seeds of 20 species. Temperatures below 10 °C limited the germination of all except Agoseris heterophylla, suggesting that in their dormant state, the majority of these species are thermally restricted. Our findings demonstrate the utility of dormancy classification as a foundation for understanding the critical regenerative traits in these ecologically important species and highlight its importance in restoration planning.


Assuntos
Ecossistema , Germinação/fisiologia , Dormência de Plantas/fisiologia , Sementes/fisiologia , Furanos/metabolismo , Giberelinas/metabolismo , Piranos/metabolismo , Sementes/metabolismo , Temperatura , Estados Unidos
6.
Plant Biol (Stuttg) ; 21(3): 415-424, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30076679

RESUMO

Grasslands across the globe are undergoing expansive degradation due to human impacts and climate change. If restoration of degraded native grassland is to be achieved at the scale now required, cost-effective means for seed-based establishment of grass species is crucial. However, grass seeds present numerous challenges associated with handling and germination performance that must be overcome to improve the efficiency of seeding. Previous research has demonstrated that complete removal of the palea and lemma (husk) maximises germination performance, hence we investigated the effects of complete husk removal on seed handling and germination of four temperate Australian grass species. Three techniques were tested to remove the husk - manual cleaning, flaming or acid digestion (the latter two followed by a manual cleaning step); these techniques were refined and adapted to the selected species, and germination responses were compared. The complete removal of the husk improved seed handling and sowability for all species. Germination was improved in Microlaena stipoides by 19% and in Rytidosperma geniculatum by 11%. Of the husk removal methods tested, flaming was detrimental to seed germination and fatal for one species (R. geniculatum). Compared to manual cleaning, sulphuric acid improved the overall efficacy of the cleaning procedure and increased germination speed (T50) in Austrostipa scabra, Chloris truncata and M. stipoides, and improved final germination in R. geniculatum by 13%. The seed processing methods developed and tested in the present study can be applied to grass species that present similar handling and germination performance impediments. These and other technological developments (seed coating and precision sowing) will facilitate more efficient grassland restoration at large scale.


Assuntos
Germinação/fisiologia , Poaceae/fisiologia , Sementes/fisiologia , Conservação dos Recursos Naturais , Ecologia
7.
J Evol Biol ; 30(9): 1674-1691, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28714217

RESUMO

The mechanism of pollinator attraction is predicted to strongly influence both plant diversification and the extent of pollinator sharing between species. Sexually deceptive orchids rely on mimicry of species-specific sex pheromones to attract their insect pollinators. Given that sex pheromones tend to be conserved among related species, we predicted that in sexually deceptive orchids, (i) pollinator sharing is rare, (ii) closely related orchids use closely related pollinators and (iii) there is strong bias in the wasp lineages exploited by orchids. We focused on species that are pollinated by sexual deception of thynnine wasps in the distantly related genera Caladenia and Drakaea, including new field observations for 45 species of Caladenia. Specialization was extreme with most orchids using a single pollinator species. Unexpectedly, seven cases of pollinator sharing were found, including two between Caladenia and Drakaea, which exhibit strikingly different floral morphology. Phylogenetic analysis of pollinators using four nuclear sequence loci demonstrated that although orchids within major clades primarily use closely related pollinator species, up to 17% of orchids within these clades are pollinated by a member of a phylogenetically distant wasp genus. Further, compared to the total diversity of thynnine wasps within the study region, orchids show a strong bias towards exploiting certain genera. Although these patterns may arise through conservatism in the chemical classes used in sex pheromones, apparent switches between wasp clades suggest unexpected flexibility in floral semiochemical production. Alternatively, wasp sex pheromones within lineages may exhibit greater chemical diversity than currently appreciated.


Assuntos
Evolução Biológica , Orchidaceae , Filogenia , Polinização , Animais , Flores , Vespas
8.
J Public Health (Oxf) ; 39(4): e235-e241, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27642124

RESUMO

Background: Compared to the general population, the Traveller community has substantial health inequalities. Vaccination coverage in Traveller children is estimated to be low and Travellers are at higher risk of vaccine-preventable diseases due to their social circumstances. Methods: Audit of vaccination history of Traveller (n = 214) and non-Traveller (n = 776) children registered at a general practice in England. The Green Book childhood immunization schedule was used as a reference standard. Results: There was significantly lower coverage for Traveller children compared to non-Traveller children for all vaccinations in the routine childhood immunization schedule. The percentage of children completing the schedule at all time points was significantly lower in the Traveller community. Conclusions: Traveller communities have significantly lower uptake of vaccinations, and therefore Travellers' children should be targeted by general practitioners for catch-up vaccination to improve outcomes for individuals and local herd immunity.


Assuntos
Roma (Grupo Étnico)/estatística & dados numéricos , Cobertura Vacinal/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Disparidades em Assistência à Saúde , Humanos , Lactente , Recém-Nascido , Irlanda/epidemiologia , Auditoria Médica , Vacinação/estatística & dados numéricos
9.
J Evol Biol ; 28(3): 601-12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25619237

RESUMO

Plants are predicted to show floral adaptation to geographic variation in the most effective pollinator, potentially leading to reproductive isolation and genetic divergence. Many sexually deceptive orchids attract just a single pollinator species, limiting opportunities to experimentally investigate pollinator switching. Here, we investigate Drakaea concolor, which attracts two pollinator species. Using pollinator choice tests, we detected two morphologically similar ecotypes within D. concolor. The common ecotype only attracted Zaspilothynnus gilesi, whereas the rare ecotype also attracted an undescribed species of Pogonothynnus. The rare ecotype occurred at populations nested within the distribution of the common ecotype, with no evidence of ecotypes occurring sympatrically. Surveying for pollinators at over 100 sites revealed that ecotype identity was not correlated with wasp availability, with most orchid populations only attracting the rare Z. gilesi. Using microsatellite markers, genetic differentiation among populations was very low (GST = 0.011) regardless of ecotype, suggestive of frequent gene flow. Taken together, these results may indicate that the ability to attract Pogonothynnus has evolved recently, but this ecotype is yet to spread. The nested distribution of ecotypes, rather than the more typical formation of ecotypes in allopatry, illustrates that in sexually deceptive orchids, pollinator switching could occur throughout a species' range, resulting from multiple potentially suitable but unexploited pollinators occurring in sympatry. This unusual case of sympatric pollinators highlights D. concolor as a promising study system for further understanding the process of pollinator switching from ecological, chemical and genetic perspectives.


Assuntos
Orchidaceae/fisiologia , Polinização , Vespas/fisiologia , Animais , Evolução Biológica , Tamanho Corporal , Ecótipo , Flores , Fluxo Gênico , Genética Populacional , Repetições de Microssatélites , Orchidaceae/genética , Simpatria , Vespas/anatomia & histologia , Austrália Ocidental
10.
Allergy ; 70(1): 80-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25331546

RESUMO

BACKGROUND: Alveolar macrophages are sentinels of the pulmonary mucosa and central to maintaining immunological homeostasis. However, their role in governing the response to allergen is not fully understood. Inappropriate responses to the inhaled environment manifest as asthma. METHODS: We utilized a mechanistic IL-13-driven model and a house dust mite allergen mucosal sensitization model of allergic airway disease to investigate the role of alveolar macrophages in regulating pulmonary inflammation. RESULTS: IL-13-dependent eosinophilic and Th2 inflammation was enhanced in mice depleted of alveolar macrophages using clodronate liposomes. Similarly, depletion of alveolar macrophages during house dust mite sensitization or established disease resulted in augmented Th2 immunity and increased allergen-specific IgG1 and IgE. Clodronate treatment also delayed the resolution of tissue inflammation following cessation of allergen challenge. Strikingly, tissue interstitial macrophages were elevated in alveolar macrophage-deficient mice identifying a new homeostatic relationship between different macrophage subtypes. A novel role for the macrophage-derived immunoregulatory cytokine IL-27 was identified in modulating Th2 inflammation following mucosal allergen exposure. CONCLUSIONS: In summary, alveolar macrophages are critical regulators of Th2 immunity and their dysregulation promotes an inflammatory environment with exacerbation of allergen-induced airway pathology. Manipulating IL-27 may provide a novel therapeutic strategy for the treatment of asthma.


Assuntos
Alérgenos/imunologia , Homeostase , Pulmão/imunologia , Macrófagos Alveolares/imunologia , Animais , Antígenos de Dermatophagoides/imunologia , Asma/imunologia , Asma/metabolismo , Asma/patologia , Modelos Animais de Doenças , Progressão da Doença , Feminino , Interleucina-13/metabolismo , Interleucina-13/farmacologia , Interleucina-27/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Camundongos , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Células Th2/imunologia , Células Th2/metabolismo
11.
Int J Obes (Lond) ; 38(1): 11-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24077005

RESUMO

This review seeks to provide a current overview of musculoskeletal pain in overweight and obese children. Databases searched were Academic Search Complete, CINAHL, Medline, Proquest Health and Medical Complete, Scopus, Google Scholar, SPORTDiscuss and Trove for studies published between 1 January 2000 and 30 December 2012. We used a broad definition of children within a 3- to 18-year age range. The search strategy included the following terms: obesity, morbid obesity, overweight, pain, musculoskeletal pain, child, adolescent, chronic pain, back pain, lower back pain, knee pain, hip pain, foot pain and pelvic pain. Two authors independently assessed each record, and any disagreement was resolved by the third author. Data were analysed using a narrative thematic approach owing to the heterogeneity of reported outcome measures. Ninety-seven records were initially identified using a variety of terms associated with children, obesity and musculoskeletal pain. Ten studies were included for thematic analysis when predetermined inclusion criteria were applied. Bone deformity and dysfunction, pain reporting and the impact of children being overweight or obese on physical activity, exercise and quality of life were the three themes identified from the literature. Chronic pain, obesity and a reduction in physical functioning and activity may contribute to a cycle of weight gain that affects a child's quality of life. Future studies are required to examine the sequela of overweight and obese children experiencing chronic musculoskeletal pain.


Assuntos
Atividade Motora , Dor Musculoesquelética/epidemiologia , Dor Musculoesquelética/etiologia , Obesidade Infantil/complicações , Obesidade Infantil/epidemiologia , Qualidade de Vida , Atividades Cotidianas , Adolescente , Criança , Pré-Escolar , Dieta , Feminino , Humanos , Masculino , Dor Musculoesquelética/prevenção & controle , Obesidade Infantil/prevenção & controle
12.
Br J Cancer ; 108(2): 409-19, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23287991

RESUMO

BACKGROUND: Effective treatment of prostate cancer should be based on targeting interactions between tumour cell signalling pathways and key converging downstream effectors. Here, we determined how the tumourigenic phosphoinositide 3-kinase/protein kinase B (PI3K/AKT), tumour-suppressive phosphatase and tensin homologue deleted on chromosome 10 (PTEN) and transforming growth factor-ß (TGF-ß) pathways are integrated via the metastasis suppressor, N-myc downstream-regulated gene-1 (NDRG1). Moreover, we assessed how the novel anti-tumour agent, Dp44mT, may target these integrated pathways by increasing NDRG1 expression. METHODS: Protein expression in Dp44mT-treated normal human prostate epithelial cells and prostate cancer cells (PC-3, DU145) was assessed by western blotting. The role of NDRG1 was examined by transfection using an NDRG1 overexpression vector or shRNA. RESULTS: Dp44mT increased levels of tumour-suppressive PTEN, and decreased phosphorylation of ERK1/2 and SMAD2L, which are regulated by oncogenic Ras/MAPK signalling. Importantly, the effects of Dp44mT on NDRG1 and p-SMAD2L expression were more marked in prostate cancer cells than normal prostate epithelial cells. This may partly explain the anti-tumour selectivity of these agents. Silencing NDRG1 expression increased phosphorylation of tumourigenic AKT, ERK1/2 and SMAD2L and decreased PTEN levels, whereas NDRG1 overexpression induced the opposite effect. Furthermore, NDRG1 silencing significantly reduced the ability of Dp44mT to suppress p-SMAD2L and p-ERK1/2 levels. CONCLUSION: NDRG1 has an important role in mediating the tumour-suppressive effects of Dp44mT in prostate cancer via selective targeting of the PI3K/AKT, TGF-ß and ERK pathways.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Células Epiteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Tiossemicarbazonas/farmacologia , Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Próstata/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta/metabolismo
13.
Int J STD AIDS ; 23(8): 544-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22930289

RESUMO

A unique feature of genitourinary (GU) medicine clinics is that patients can book appointments themselves. The aim of this study was to assess how long it takes and the barriers that exist when making an appointment in a UK GU medicine clinic. Male and female researchers recorded the number of attempts needed to make a successful contact, how the call was dealt with, and the time taken for the call to be initially answered and then completed; 72% (479/666) of the telephone contacts were answered on the first attempt (range: 1-17). The median length of the total call was one minute 51 seconds (range: 15 seconds to eight minutes, six seconds) but male callers took a mean of 40 seconds longer to complete a call (P < 0.001), reflecting additional and often intrusive questions they were asked compared with female researchers. Care should be taken to ensure that the first point of contact with a clinic is favourable as it reflects on how an entire service may be perceived.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Agendamento de Consultas , Doenças dos Genitais Femininos/terapia , Doenças dos Genitais Masculinos/terapia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Telefone/estatística & dados numéricos , Feminino , Humanos , Masculino , Fatores Sexuais , Fatores de Tempo , Reino Unido
14.
Ann Rheum Dis ; 70(5): 864-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21177295

RESUMO

OBJECTIVES: The genetic aetiology of osteoarthritis has not yet been elucidated. To enable a well-powered genome-wide association study (GWAS) for osteoarthritis, the authors have formed the arcOGEN Consortium, a UK-wide collaborative effort aiming to scan genome-wide over 7500 osteoarthritis cases in a two-stage genome-wide association scan. Here the authors report the findings of the stage 1 interim analysis. METHODS: The authors have performed a genome-wide association scan for knee and hip osteoarthritis in 3177 cases and 4894 population-based controls from the UK. Replication of promising signals was carried out in silico in five further scans (44,449 individuals), and de novo in 14 534 independent samples, all of European descent. RESULTS: None of the association signals the authors identified reach genome-wide levels of statistical significance, therefore stressing the need for corroboration in sample sets of a larger size. Application of analytical approaches to examine the allelic architecture of disease to the stage 1 genome-wide association scan data suggests that osteoarthritis is a highly polygenic disease with multiple risk variants conferring small effects. CONCLUSIONS: Identifying loci conferring susceptibility to osteoarthritis will require large-scale sample sizes and well-defined phenotypes to minimise heterogeneity.


Assuntos
Osteoartrite do Quadril/genética , Osteoartrite do Joelho/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Herança Multifatorial , Polimorfismo de Nucleotídeo Único
15.
J AOAC Int ; 93(2): 576-86, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20480906

RESUMO

The automated method for enumeration of Escherichia coli, TEMPO EC, in foods uses a dehydrated culture medium and enumeration card containing 48 wells across three different dilutions for the automatic determination of the most probable number (MPN). The alternative method was compared in a multilaboratory collaborative study to AOAC Official Method 966.24. Six food types were artificially contaminated with E. coli: raw ground beef, bagged lettuce, cooked chicken, pasteurized crabmeat, frozen green beans, and pasteurized whole milk. All foods were analyzed for E. coli counts by 11 collaborating laboratories throughout the United States. Test portions from the six food types each contaminated at four different contamination levels were evaluated. The study demonstrated that the TEMPO EC method is a reliable, automated assay for the enumeration of E. coli in foods.


Assuntos
Contagem de Colônia Microbiana/métodos , Escherichia coli/metabolismo , Contaminação de Alimentos , Microbiologia de Alimentos , Animais , Automação , Bovinos , Galinhas/microbiologia , Análise de Alimentos , Laboratórios/normas , Carne/microbiologia , Reprodutibilidade dos Testes , Projetos de Pesquisa , Alimentos Marinhos/microbiologia , Verduras/microbiologia
16.
J Steroid Biochem Mol Biol ; 121(1-2): 164-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20399269

RESUMO

Ultraviolet (UV) irradiation causes DNA damage in skin cells, immunosuppression and photocarcinogenesis. 1alpha,25-dihydroxyvitamin D3 (1,25D) reduces UV-induced DNA damage in the form of cyclobutane pyrimidine dimers (CPD) in human keratinocytes in culture and in mouse and human skin. UV-induced immunosuppression is also reduced in mice by 1,25D, in part due to the reduction in CPD and a reduction in interleukin (IL-6. The cis-locked analog, 1alpha,25-dihydroxylumisterol3 (JN), which has almost no transactivating activity, reduces UV-induced DNA damage, apoptosis and immunosuppression with similar potency to 1,25D, consistent with a non-genomic signalling mechanism. The mechanism of the reduction in DNA damage in the form of CPD is unclear. 1,25D doubles nuclear expression of p53 compared to UV alone, which suggests that 1,25D facilitates DNA repair. Yet expression of a key DNA repair gene, XPG is not affected by 1,25D. Chemical production of CPD has been described. Incubation of keratinocytes with a nitric oxide donor, SNP, induces CPD in the dark. We previously reported that 1,25D reduced UV-induced nitrite in keratinocytes, similar to aminoguanidine, an inhibitor of nitric oxide synthase. A reduction in reactive nitrogen species has been shown to facilitate DNA repair, but in view of these findings may also reduce CPD formation via a novel mechanism.


Assuntos
Calcitriol/análogos & derivados , Calcitriol/farmacologia , Animais , Células Cultivadas , Dano ao DNA , Reparo do DNA , Ergosterol/análogos & derivados , Ergosterol/farmacologia , Guanidinas/farmacologia , Humanos , Interleucina-6/metabolismo , Queratinócitos/citologia , Queratinócitos/efeitos da radiação , Camundongos , Modelos Biológicos , Óxido Nítrico Sintase/metabolismo , Espécies Reativas de Nitrogênio , Raios Ultravioleta
17.
Occup Med (Lond) ; 60(3): 184-92, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20423949

RESUMO

AIMS: To evaluate current research on the health, safety and health promotion needs of older workers by identifying age-related change, whether older workers need support and evidence of successful intervention in the workplace. METHODS: Using a systematic review methodology, databases were searched identifying 180 publications. Each publication was reviewed and data were extracted. Evidence was assessed for quality using the three-star system. RESULTS: The review identified that there are a number of age-related physical and psychological changes. However, these changes can be moderated by increased physical activity, intellectual activity and other lifestyle factors. Sensory abilities are also subject to change but some of these can be accommodated via equipment or workplace adjustments. In reviewing accident data, although older workers are at a reduced risk of accidents, they are more at risk of fatal accidents. Ill-health data identify that many chronic diseases can be controlled and adjustments put in place in the work environment. A number of intervention studies were identified but few were of high quality. The research suggests that occupational health intervention can reduce the risk of early retirement from the workplace; health promotion interventions are seen as positive by older workers but it is important to ensure equal access to all workers in such promotions. CONCLUSIONS: The review identified that there are still a large number of research gaps including the lack of longitudinal research; no further analysis on fatal accidents or understanding of the high prevalence of musculoskeletal disorders and stress and anxiety in older workers.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Envelhecimento , Promoção da Saúde/organização & administração , Saúde Ocupacional , Licença Médica/estatística & dados numéricos , Local de Trabalho/organização & administração , Acidentes de Trabalho/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Doença Crônica , Feminino , Promoção da Saúde/métodos , Transtornos de Estresse por Calor/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Doenças Musculoesqueléticas/epidemiologia , Resistência Física/fisiologia , Equilíbrio Postural/fisiologia , Aposentadoria/estatística & dados numéricos , Fatores de Risco , Gestão da Segurança/organização & administração , Fatores Sexuais , Reino Unido/epidemiologia , Tolerância ao Trabalho Programado/fisiologia , Carga de Trabalho , Adulto Jovem
18.
Immunopharmacol Immunotoxicol ; 32(1): 171-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19821644

RESUMO

BACKGROUND AND AIM: The pharmacokinetics of clenbuterol in equine urine and blood was investigated. MATERIAL AND METHODS: Urine and blood samples were collected following 3-day multiple oral administrations. The samples were examined using enzyme-linked immunosorbent assay and further confirmed by solid phase extraction and capillary electrophoresis. RESULTS: Urinary clenbuterol was detectable until day 14 after the last dose. The urinary excretion of clenbuterol was characterized by a biphasic pattern. The half-lives of the bi-exponential elimination (t(1/2alpha) and t(1/2beta)) for urinary clenbuterol were about 12.1 and 48 hours. After a single oral administration (4 microg/kg) of clenbuterol, the half-life of serum clenbuterol was approximately 11.4 hours.


Assuntos
Agonistas Adrenérgicos beta/farmacocinética , Clembuterol/administração & dosagem , Clembuterol/farmacocinética , Administração Oral , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Cavalos , Masculino , Distribuição Tecidual
19.
Ann R Coll Surg Engl ; 91(7): W1-3, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19833008

RESUMO

A case is described of a successful radioguided forearm graft parathyroidectomy. This is the first report of both pre-operative diagnostic and successful intra-operative localisation during a single procedure, of autologous transplanted parathyroid tissue.


Assuntos
Antebraço/cirurgia , Hiperparatireoidismo/cirurgia , Paratireoidectomia/métodos , Adulto , Humanos , Hiperparatireoidismo/diagnóstico , Hiperplasia/complicações , Hiperplasia/diagnóstico , Masculino , Compostos Radiofarmacêuticos , Recidiva , Tecnécio Tc 99m Sestamibi , Transplante Autólogo/métodos , Resultado do Tratamento
20.
Ann Bot ; 104(5): 833-44, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19620135

RESUMO

BACKGROUND AND AIMS: The Sapindaceae is one of 17 plant families in which seed dormancy is caused by a water-impermeable seed or fruit coat (physical dormancy, PY). However, until now the water gap in Sapindaceae had not been identified. The primary aim of this study was to identify the water gap in Dodonaea petiolaris (Sapindaceae) seeds and to describe its basic morphology and anatomy. METHODS: Seed fill, viability, water-uptake (imbibition) and other characteristics were assessed for D. petiolaris seeds. The location and structure of the water gap were investigated using a blocking experiment, time series photography, scanning electron microscopy and light microscopy. Dodonaea petiolaris seeds with PY also were assessed for loss of PY at four ecologically significant temperatures under moist and dry conditions. Seeds of three other species of Sapindaceae were examined for presence of a water gap. KEY RESULTS: The water gap in D. petiolaris seeds was identified as a small plug in the seed coat adjacent to the hilum and opposite the area where the radicle emerges. The plug was dislodged (i.e. water gap opened = dormancy break) by dipping seeds in boiling water for 2.5 min or by incubating seeds on a moist substrate at 20/35 degrees C for 24 weeks. Layers of cells in the plug, including palisade and subpalisade, are similar to those in the rest of the seed coat. The same kind of water gap was found in three other species of Sapindaceae, Diplopeltis huegelii, Distichostemon hispidulus and Dodonaea aptera. CONCLUSIONS: Following dormancy break (opening of water gap), initial uptake of water by the seed occurs only through the water gap. Thus, the plug must be dislodged before the otherwise intact seed can germinate. The anatomy of the plug is similar to water gaps in some of the other plant families with PY.


Assuntos
Sapindaceae/fisiologia , Sementes/fisiologia , Germinação/fisiologia , Microscopia Eletrônica de Varredura , Sementes/ultraestrutura , Água/fisiologia
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