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1.
Nutr Neurosci ; : 1-19, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287652

RESUMO

Many epidemiological studies have shown the beneficial effects of a largely plant-based diet, and the strong association between the consumption of a Mediterranean-type diet with healthy aging including a lower risk of cognitive decline. The Mediterranean diet is characterized by a high intake of olive oil, fruits and vegetables and is rich in dietary fiber and polyphenols - both of which have been postulated to act as important mediators of these benefits. Polyphenols are large molecules produced by plants to protect them from environmental threats and injury. When ingested by humans, as little as 5% of these molecules are absorbed in the small intestine with the majority metabolized by the gut microbiota into absorbable simple phenolic compounds. Flavan-3-ols, a type of flavonoid, contained in grapes, berries, pome fruits, tea, and cocoa have been associated with many beneficial effects on several risk factors for cardiovascular disease, cognitive function and brain regions involved in memory formation. Both preclinical and clinical studies suggest that these brain and heart benefits can be attributed to endothelial vascular effects and anti-inflammatory properties among others. More recently the gut microbiota has emerged as a potential modulator of the aging brain and intriguingly polyphenols have been shown to alter microbiota composition and be metabolized by different microbial species. However, there is a need for well controlled studies in large populations to identify predictors of response, particularly given the vast inter-individual variation of human gut microbiota.

2.
Phys Rev Lett ; 129(23): 232502, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36563213

RESUMO

Neutrinoless double beta decay (0νßß) processes sample a wide range of intermediate forbidden nuclear transitions, which may be impacted by quenching of the axial vector coupling constant (g_{A}/g_{V}), the uncertainty of which plays a pivotal role in determining the sensitivity reach of 0νßß experiments. In this Letter, we present measurements performed on a high-resolution LiInSe_{2} bolometer in a "source=detector" configuration to measure the spectral shape of the fourfold forbidden ß decay of ^{115}In. The value of g_{A}/g_{V} is determined by comparing the spectral shape of theoretical predictions to the experimental ß spectrum taking into account various simulated background components as well as a variety of detector effects. We find evidence of quenching of g_{A}/g_{V} at >5σ with a model-dependent quenching factor of 0.655±0.002 as compared to the free-nucleon value for the interacting shell model. We also measured the ^{115}In half-life to be [5.18±0.06(stat)_{-0.015}^{+0.005}(sys)]×10^{14} yr within the interacting shell model framework. This Letter demonstrates the power of the bolometeric technique to perform precision nuclear physics single-ß decay measurements, which along with improved nuclear modeling can help reduce the uncertainties in the calculation of several decay nuclear matrix elements including those used in 0νßß sensitivity calculations.

3.
J Environ Manage ; 304: 114264, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34906809

RESUMO

Enhanced efficiency fertilisers (EEF) may reduce nitrogen (N) losses and improve uptake efficiency through synchronising N release with in-season plant requirements. We hypothesised that EEF formed via matrix encapsulation in biodegradable polymers will improve N use efficiency when compared to conventional urea fertiliser. This hypothesis was investigated for two biodegradable polymer matrices: polyhydroxyalkanoate (PHA), containing 11.6% urea (by mass), and polybutylene-adipate-co-terephthalate (PBAT), containing either 19.4 or 32.7% urea; and two contrasting soil types: sand and clay. Nitrogen availability and form was investigated under leaching conditions (water) with a growth accelerator pot experiment involving a horticultural crop and novel non-destructive three-dimensional scanning to measure in-season biomass development. The PBAT 32.7% formulation enabled greater above ground biomass production at both 50 and 100 kg N ha-1 equivalent application rates compared to conventional urea. For the sandy soil, plant scanning indicated that improved uptake performance with PBAT 32.7% was probably the result of greater N availability after 25 days than for conventional urea. Two of the encapsulated formulations (PHA and PBAT 19.4%) tended to decrease nitrogen leaching losses relative to urea (P < 0.05 for the red clay soil). However, decreased N leaching loss was accompanied by poorer N uptake performance, indicative of N being less available in these biopolymer formulations. A snapshot of nitrous oxide emissions collected during peak nitrate concentration (prior to planting and leaching) suggested that the biopolymers promoted N loss via gaseous emission relative to urea in the sandy soil (P < 0.05), and carbon dioxide emissions data suggested that biopolymer-carbon increased microbial activity (P < 0.1). Controlled testing of N release in water was a poor predictor of biomass production and leaching losses. The diverse behaviours of the tested formulations present the potential to optimise biopolymers and their N loadings by taking into account soil and environmental factors that influence the efficient delivery of N to target crops. The greater N uptake efficiency demonstrated for the PBAT 32.7% formulation confirms our hypothesis that matrix encapsulation can enable better synchronisation of N release with crop requirements and decrease leaching losses.


Assuntos
Fertilizantes , Objetivos , Agricultura , Produtos Agrícolas , Fertilizantes/análise , Nitrogênio/análise , Polímeros , Solo
4.
Blood ; 133(5): 470-480, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30545833

RESUMO

Malaria remains a major global threat to human health and economic development. Microvascular lesions caused by Plasmodium falciparum-infected human erythrocytes/red blood cells are hallmarks of severe pathogenesis contributing to high mortality, particularly in children from sub-Saharan Africa. In this study, we used a phage display complementary DNA library screening strategy to identify P falciparum glutamic acid-rich protein (PfGARP) as a secreted ligand that recognizes an ectodomain of human erythrocyte anion-exchanger, band 3/AE1, as a host receptor. Domain mapping of PfGARP revealed distinct nonoverlapping repeats encoding the immune response epitopes and core erythrocyte-binding activity. Synthetic peptides derived from the erythrocyte-binding repeats of PfGARP induced erythrocyte aggregation reminiscent of the rosetting phenomenon. Using peptides derived from the immunogenic repeats, a quantitative immunoassay was developed to detect a selective immune response against PfGARP in human plasma samples obtained from patients in rural Mali, suggesting the feasibility of PfGARP as a potential biomarker of disease progression. Collectively, our results suggest that PfGARP may play a functional role in enhancing the adhesive properties of human erythrocytes by engaging band 3 as a host receptor. We propose that immunological and pharmacological inhibition of PfGARP may unveil new therapeutic options for mitigating lesions in cerebral and pregnancy-associated malaria.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Eritrócitos/parasitologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Malária Falciparum/metabolismo , Plasmodium falciparum/fisiologia , Proteínas de Protozoários/metabolismo , Animais , Células CHO , Agregação Celular , Cricetulus , Progressão da Doença , Eritrócitos/metabolismo , Eritrócitos/patologia , Feminino , Interações Hospedeiro-Parasita , Humanos , Malária Falciparum/parasitologia , Malária Falciparum/patologia , Camundongos Endogâmicos BALB C , Ligação Proteica
5.
Eur Cell Mater ; 40: 189-202, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33152099

RESUMO

In vitro tissue engineered bone constructs have been developed, but models which mimic both formation and resorption in parallel are still lacking. To be used as a model for the bone remodeling process, the formation and resorption of mineralised tissue volume over time needs to be visualised, localised and quantified. The goal of this study was to develop a human 3D osteoblast-osteoclast co-culture in which 1) osteoblasts deposit mineralised matrix, 2) monocytes differentiate into resorbing osteoclasts, and 3) the formation and resorption of mineralised matrix could be quantified over time using micro-computed tomography (µCT). Mesenchymal stromal cells were seeded on silk fibroin scaffolds and differentiated towards osteoblasts to create mineralised constructs. Thereafter, monocytes were added and differentiated towards osteoclasts. The presence of osteoblasts and osteoclasts was confirmed using immunohistochemistry. Osteoclastic activity was confirmed by measuring the increased release of osteoclast marker tartrate resistant acid phosphatase (TRAP), suggesting that osteoclasts were actively resorbing mineralised tissue. Resorption pits were visualised using scanning electron microscopy. Mineralised matrix formation and resorption were quantified using µCT and subsequent scans were registered to visualise remodelling. Both formation and resorption occurred in parallel in the co-culture. The resorbed tissue volume exceeded the formed tissue volume after day 12. In conclusion, the current model was able to visualise, localise and quantify mineralised matrix formation and resorption. Such a model could be used to facilitate fundamental research on bone remodeling, facilitate drug testing and may have clinical implications in personalised medicine by allowing the use of patient cells.


Assuntos
Reabsorção Óssea/patologia , Reabsorção Óssea/fisiopatologia , Calcificação Fisiológica , Imageamento Tridimensional , Osteoblastos/patologia , Osteoclastos/patologia , Animais , Bombyx , Diferenciação Celular , Técnicas de Cocultura , Matriz Extracelular/metabolismo , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Monócitos/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteócitos/metabolismo , Fosfatase Ácida Resistente a Tartarato/metabolismo , Engenharia Tecidual , Adulto Jovem
6.
Epidemiol Infect ; 147: e240, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364577

RESUMO

Hendra virus (HeV) continues to cause fatal infection in horses and threaten infection in close-contact humans in eastern Australia. Species of Pteropus bats (flying-foxes) are the natural reservoir of the virus. We caught and sampled flying-foxes from a multispecies roost in southeast Queensland, Australia on eight occasions between June 2013 and June 2014. The effects of sample date, species, sex, age class, body condition score (BCS), pregnancy and lactation on HeV antibody prevalence, log-transformed median fluorescent intensity (lnMFI) values and HeV RNA status were assessed using unbalanced generalised linear models. A total of 1968 flying-foxes were sampled, comprising 1012 Pteropus alecto, 742 P. poliocephalus and 214 P. scapulatus. Sample date, species and age class were each statistically associated with HeV RNA status, antibody status and lnMFI values; BCS was statistically associated with HeV RNA status and antibody status. The findings support immunologically naïve sub-adult P. alecto playing an important role in maintaining HeV infection at a population level. The biological significance of the association between BCS and HeV RNA status, and BCS and HeV antibody status, is less clear and warrants further investigation. Contrary to previous studies, we found no direct association between HeV infection and pregnancy or lactation. The findings in P. poliocephalus suggest that HeV exposure in this species may not result in systemic infection and virus excretion, or alternatively, may reflect assay cross-reactivity with another (unidentified) henipavirus.


Assuntos
Quirópteros/virologia , Surtos de Doenças/estatística & dados numéricos , Transmissão de Doença Infecciosa/estatística & dados numéricos , Vírus Hendra/isolamento & purificação , Infecções por Henipavirus/epidemiologia , Doenças dos Cavalos/epidemiologia , Fatores Etários , Animais , Anticorpos Antivirais/sangue , Austrália/epidemiologia , Composição Corporal , Feminino , Cavalos , Humanos , Gravidez , Prevalência , Queensland/epidemiologia , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Medição de Risco , Estações do Ano
7.
Support Care Cancer ; 27(5): 1775-1781, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30146666

RESUMO

PURPOSE: Chronic pain, depression, and fatigue are common effects resulting from the cancer experience; new interventions are needed. This study examined the effect of Reimagine, an online symptom self-management curriculum that teaches coping skills, on key outcomes. METHODS: Adult breast cancer survivors with chronic pain were recruited from the Army of Women volunteer registry for this randomized controlled trial and randomized 1:1 to Reimagine or usual care conditions. Electronic surveys collected demographic, clinical, and outcome data at baseline and 18 weeks post-intervention. RESULTS: Participants (N = 89) were mean age 56.7 ± 8.7 years; 67% married; 58% employed; mean years since diagnosis 8.2 ± 6.6; and 89% were in remission or cured of their breast cancer. There was a significant difference in the change in depression scores for treatment (M = - 1.7, SD = 4.5) and usual care (M = 0.3, SD = 3.8) conditions; t(85) = - 2.3, p = .03. Difference in the change in fatigue scores was significant for treatment (M = 4.8, SD = 9.0) and usual care (M = 1.2, SD = 6.6) conditions; t(87) = 2.2, p = .03. Most Reimagine users (94%) would recommend the curriculum to others. CONCLUSIONS: These results suggest that Reimagine has an effect on depression and fatigue symptoms for breast cancer survivors. Online programs can be a feasible and effective alternative to in-person support. Additional research is recommended with larger and more diverse samples.


Assuntos
Neoplasias da Mama/terapia , Dor do Câncer/terapia , Sobreviventes de Câncer/psicologia , Terapia Cognitivo-Comportamental/métodos , Educação a Distância/métodos , Educação de Pacientes como Assunto/métodos , Autogestão/educação , Adaptação Psicológica , Neoplasias da Mama/psicologia , Dor do Câncer/psicologia , Currículo , Fadiga/psicologia , Fadiga/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Qualidade de Vida , Autogestão/métodos , Inquéritos e Questionários
8.
Parasite Immunol ; 40(4): e12515, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29314141

RESUMO

This study investigated the local immune response at larval attachment sites in Santa Gertrudis cattle with low and high levels of tick resistance. Skin samples with tick larvae attached were collected from Santa Gertrudis cattle at the end of a period of 25 weekly infestations, when the animals manifested highly divergent tick-resistant phenotypes. There was a tendency for more CD3+ , CD4+ , CD8+ , CD25+ , γδ T cells and neutrophils to concentrate at larval tick attachment site in susceptible cattle than in resistant cattle but the differences were significant only for γδ T cells and CD4+ cells. Most of the cattle developed intra-epidermal vesicles at the larval attachment site but the predominant cell within or around the vesicles was the neutrophil in susceptible animals and eosinophil in the resistant animals. The monoclonal antibodies (mAbs) specific for CD45 and CD45 RO antigens reacted with skin leucocytes from a higher number of susceptible cattle than resistant cattle. Our data suggest that some of the cellular responses mounted at larval attachment site are not involved in tick protection. The mAbs specific for CD45 and CD45 RO directly, or a test for CD45 genotype might be developed as markers of tick susceptibility or resistance.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/parasitologia , Larva/imunologia , Antígenos Comuns de Leucócito/imunologia , Neutrófilos/imunologia , Rhipicephalus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Bovinos , Suscetibilidade a Doenças/imunologia , Genótipo , Fenômenos do Sistema Imunitário , Leucócitos/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Rhipicephalus/fisiologia , Pele/imunologia , Pele/parasitologia , Infestações por Carrapato/imunologia
9.
Phys Chem Chem Phys ; 20(6): 4340-4346, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29367990

RESUMO

We present a simple and non-destructive method for characterizing and quantifying the quality of two-dimensional (2D) close-packed arrays of submicron dielectric spheres. Utilizing radiative losses of photonic modes created by the 2D crystals into dielectric substrates we are able to monitor the quality of the particle monolayer during assembly and the size evolution of the individual particles during dry etching. Using an advanced interfacial assembly technique we prepare particle monolayers on glass and characterize the spectral behaviour of the radiative loss regarding different lattice constants, dielectric substrates and layer qualities. The effect of diameter reduction during dry etching is analysed and a simple model is proposed, which enables non-destructive, on spot characterization of the particle layer with sub-20 nm resolution using UV-vis spectroscopy.

10.
Soft Matter ; 13(37): 6297-6303, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28920620

RESUMO

The current modification of polydimethylsiloxane (PDMS) substrates via oxygen plasma treatment causes surface cracks. Here, we demonstrate a method to prevent crack formation by chemical treatment. Chemical modification renders the surface hydrophilic for several days and is effective in preserving the elasticity of the PDMS surface at the nanoscale level.

11.
J Phys Chem A ; 121(15): 2911-2917, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28375607

RESUMO

Analyzing the electronic properties of individual terphenyldithiol (TPT) molecules in a temperature range of 30-300 K using cryogenic mechanically controllable break junctions, we observe an unexpected change of the transport mechanism with temperature for this linear and symmetric aromatic molecule. Whereas the work function (∼3.8 eV) and molecular energy level (∼0.8 to ∼1 eV depending on the analysis of the data) of TPT are temperature-independent, elastic tunneling dominates charge transport at low temperatures, whereby an inelastic transport (via hopping) sets in at about 100 K. The molecular level of TPT lies around 1 eV and is temperature-independent. This unusual temperature dependence agrees with recent predictions for other short molecules using density-functional-based transport studies as well as experimental observations obtained for similar relatively short rodlike molecules.

12.
Artigo em Inglês | MEDLINE | ID: mdl-28497519

RESUMO

The period of survivorship has been identified as a distinct phase of the cancer continuum, and the key role of primary care providers in caring for cancer survivors has been recognized. However, much of the focus to date has been placed on cancer survivors who are treated with curative intent and survive cancer-free. Receiving less attention are those who are living with advanced, non-curative cancer. In this commentary, we review the current evidence about the characteristics of these survivors, their unmet needs and receipt of health care. We offer insights into future research, education and policy initiatives aiming to enhance the care for this population.


Assuntos
Neoplasias/terapia , Atenção Primária à Saúde , Sobrevivência , Atenção à Saúde/normas , Previsões , Humanos , Papel Profissional , Sobreviventes
13.
J Wound Care ; 26(11): 680-690, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29131752

RESUMO

Surfactants are widely used as detergents, emulsifiers, wetting agents, foaming agents and dispersants in the cosmetics, hygiene, food and oil industries. Their use in a clinical setting is also common, particularly within the field of wound care. Many wound cleansers contain surfactants and subsequently there is available data that shows the growing potential of these wound cleansers in the enhancement of wound closure. The presence of microorganisms in wounds has been recognised as a significant factor that delay healing. In complex or chronic wounds that are complicated by biofilms, persistent inflammation or the production of non-viable tissue and slough, the use of surfactants has been shown to aid in the removal of these barriers to wound healing. The use of concentrated surfactant(poloxamer) based wound dressings represent an important component of wound management. Consequently, this article will discuss the effect of clinically used surfactants, with specific focus on a concentrated poloxamer for use against wound biofilm.


Assuntos
Bandagens , Biofilmes , Poloxâmero/uso terapêutico , Tensoativos/uso terapêutico , Infecção dos Ferimentos/terapia , Ferimentos e Lesões/terapia , Humanos
14.
Ter Arkh ; 89(6): 21-29, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28745685

RESUMO

AIM: To analyze the clinical and morphological manifestations of membranous nephropathy (MN) and to evaluate the efficiency of its therapy. MATERIAL AND METHODS: MN cases in 2009 to 2016 were retrospectively detected with a subsequent analysis of patients with primary MN (PMN). The titer of IgG-autoantibodies to phospholipase A2 receptor (anti-PLA2R Ab) was determined by an indirect immunofluorescence assay. Treatment outcomes, such as the time course of changes in proteinuria, nephrotic syndrome (NS), and the development of complete and partial remissions (CR and PR), were assessed. RESULTS: MN was detected in 201 cases; the secondary etiology of the disease was established in 24.9%. The prevalence of MN among morphologically confirmed glomerulopathies was 14%; that of PMN was 10.4%. The median period to diagnosis PMN was 8 (5; 19) months. 150 patients with PMN (66.7% were men; age was 50±15 years) were distributed according to the following morphological stages: Stages I (23.9%), II (48.5%), III (26.1%), and IV (1.5%). Elevated anti-PLA2R Ab levels were found in 51.6% of cases; NS in the presence of proteinuria was detected in 85.6% of patients. An estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73 m2 was seen in 25% of cases. Treatment outcomes were evaluated in 80 cases; the median follow-up period was 19 (8; 40) months. 68% of cases had CR (32%) or PR (36%) with a median follow-up of 26 (13; 44) months. Spontaneous CRs or PRs were observed in 7.5% of the patients. Multivariate analysis showed that the probability of CR or PR increased 3.2-fold in the use of cyclophosphamide and/or cyclosporine and decreased as eGFR dropped. CONCLUSION: In Russia, PMN is a common type of glomerulopathy, the specific features of which should include the low rates of spontaneous remissions and detection of anti-PLA2R Abs. For renal protection, the majority of patients with PMN require timely diagnosis and treatment; individualization of the choice of treatment and its enhanced efficiency call for further investigations.


Assuntos
Glomerulonefrite Membranosa/epidemiologia , Adulto , Idoso , Feminino , Glomerulonefrite Membranosa/sangue , Glomerulonefrite Membranosa/classificação , Glomerulonefrite Membranosa/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Federação Russa/epidemiologia
15.
Langmuir ; 32(32): 8084-91, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27444884

RESUMO

The interaction between proteins and solid surfaces can influence their conformation and therefore also their activity and affinity. These interactions are highly specific for the respective combination of proteins and solids. Consequently, it is desirable to investigate the conformation of proteins on technical surfaces, ideally at single molecule level, and to correlate the results with their activity. This is in particular true for biosensors where the conformation-dependent target affinity of an immobilized receptor determines the sensitivity of the sensor. Here, we investigate for the first time the immobilization and orientation of antibodies (Abs) photoactivated by a photonic immobilization technique (PIT), which has previously demonstrated to enhance binding capabilities of antibody receptors. The photoactivated immunoglobulins are immobilized on ultrasmooth template stripped gold films and investigated by atomic force microscopy (AFM) at the level of individual molecules. The observed protein orientations are compared with results of nonactivated antibodies adsorbed on similar gold films and mica reference samples. We find that the behavior of Abs is similar for mica and gold when the protein are not treated (physisorption), whereas smaller contact area and larger heights are measured when Abs are treated (PIT). This is explained by assuming that the activated antibodies tend to be more upright compared with nonirradiated ones, thereby providing a better exposure of the binding sites. This finding matches the observed enhancement of Abs binding efficiency when PIT is used to functionalize gold surface of QCM-based biosensors.


Assuntos
Anticorpos Imobilizados/química , Imunoglobulina G/química , Microscopia de Força Atômica , Raios Ultravioleta , Animais , Processos Fotoquímicos
16.
J Microsc ; 263(1): 78-86, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26820619

RESUMO

The preparation of biological cells for either scanning or transmission electron microscopy requires a complex process of fixation, dehydration and drying. Critical point drying is commonly used for samples investigated with a scanning electron beam, whereas resin-infiltration is typically used for transmission electron microscopy. Critical point drying may cause cracks at the cellular surface and a sponge-like morphology of nondistinguishable intracellular compartments. Resin-infiltrated biological samples result in a solid block of resin, which can be further processed by mechanical sectioning, however that does not allow a top view examination of small cell-cell and cell-surface contacts. Here, we propose a method for removing resin excess on biological samples before effective polymerization. In this way the cells result to be embedded in an ultra-thin layer of epoxy resin. This novel method highlights in contrast to standard methods the imaging of individual cells not only on nanostructured planar surfaces but also on topologically challenging substrates with high aspect ratio three-dimensional features by scanning electron microscopy.


Assuntos
Resinas Epóxi , Microscopia Eletrônica de Varredura/métodos , Nanoestruturas/ultraestrutura , Análise de Célula Única/métodos , Inclusão do Tecido/métodos , Animais , Células Cultivadas , Córtex Cerebral/citologia , Dessecação , Resinas Epóxi/isolamento & purificação , Imageamento Tridimensional/métodos , Neurônios/ultraestrutura , Ratos Wistar
17.
Epidemiol Infect ; 144(15): 3176-3183, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27357144

RESUMO

Hendra virus (HeV) was first described in 1994 in an outbreak of acute and highly lethal disease in horses and humans in Australia. Equine cases continue to be diagnosed periodically, yet the predisposing factors for infection remain unclear. We undertook an analysis of equine submissions tested for HeV by the Queensland government veterinary reference laboratory over a 20-year period to identify and investigate any patterns. We found a marked increase in testing from July 2008, primarily reflecting a broadening of the HeV clinical case definition. Peaks in submissions for testing, and visitations to the Government HeV website, were associated with reported equine incidents. Significantly differing between-year HeV detection rates in north and south Queensland suggest a fundamental difference in risk exposure between the two regions. The statistical association between HeV detection and stockhorse type may suggest that husbandry is a more important risk determinant than breed per se. The detection of HeV in horses with neither neurological nor respiratory signs poses a risk management challenge for attending veterinarians and laboratory staff, reinforcing animal health authority recommendations that appropriate risk management strategies be employed for all sick horses, and by anyone handling sick horses or associated biological samples.


Assuntos
Vírus Hendra/fisiologia , Infecções por Henipavirus/veterinária , Doenças dos Cavalos/epidemiologia , Animais , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/virologia , Doenças dos Cavalos/virologia , Cavalos , Prevalência , Queensland/epidemiologia , Fatores de Risco
18.
Int J Biometeorol ; 60(12): 1961-1968, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27174414

RESUMO

Exposure to hot environments affects milk yield (MY) and milk composition of pasture and feed-pad fed dairy cows in subtropical regions. This study was undertaken during summer to compare MY and physiology of cows exposed to six heat-load management treatments. Seventy-eight Holstein-Friesian cows were blocked by season of calving, parity, milk yield, BW, and milk protein (%) and milk fat (%) measured in 2 weeks prior to the start of the study. Within blocks, cows were randomly allocated to one of the following treatments: open-sided iron roofed day pen adjacent to dairy (CID) + sprinklers (SP); CID only; non-shaded pen adjacent to dairy + SP (NSD + SP); open-sided shade cloth roofed day pen adjacent to dairy (SCD); NSD + sprinkler (sprinkler on for 45 min at 1100 h if mean respiration rate >80 breaths per minute (NSD + WSP)); open-sided shade cloth roofed structure over feed bunk in paddock + 1 km walk to and from the dairy (SCP + WLK). Sprinklers for CID + SP and NSD + SP cycled 2 min on, 12 min off when ambient temperature >26°C. The highest milk yields were in the CID + SP and CID treatments (23.9 L cow-1 day-1), intermediate for NSD + SP, SCD and SCP + WLK (22.4 L cow-1 day-1), and lowest for NSD + WSP (21.3 L cow-1 day-1) (P < 0.05). The highest (P < 0.05) feed intakes occurred in the CID + SP and CID treatments while intake was lowest (P < 0.05) for NSD + WSP and SCP + WLK. Weather data were collected on site at 10-min intervals, and from these, THI was calculated. Nonlinear regression modelling of MY × THI and heat-load management treatment demonstrated that cows in CID + SP showed no decline in MY out to a THI break point value of 83.2, whereas the pooled MY of the other treatments declined when THI >80.7. A combination of iron roof shade plus water sprinkling throughout the day provided the most effective control of heat load.


Assuntos
Criação de Animais Domésticos/métodos , Temperatura Alta/efeitos adversos , Abrigo para Animais , Leite , Animais , Temperatura Corporal , Bovinos , Feminino , Umidade , Gravidez , Taxa Respiratória , Clima Tropical
19.
Bioprocess Biosyst Eng ; 39(9): 1441-54, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27174225

RESUMO

In this study, kinetic parameters were determined for the biodegradation of BTX compounds in a fixed-bed reactor with immobilized biomass, fed with mono- and multicomponent systems. The parameter estimation was achieved through an algorithm using the finite volume method. Different kinetic models were evaluated. The Monod model proved to be suitable to predict the experimental data for the biodegradation individual BTX compound. In multicomponent systems, it was found that the presence of more than one compound tends to cause competitive inhibition. To identify the models that best fit the experimental data, a statistical analysis using the F test was applied. For the two- and three-component systems the presence of more than one compound tends to cause competitive inhibition. In this study, it was possible to predict kinetic parameters in mono- and multicomponent systems as well as different operation conditions for a fixed-bed reactor with immobilized biomass.


Assuntos
Benzeno/metabolismo , Biodegradação Ambiental , Biomassa , Tolueno/metabolismo , Xilenos/metabolismo , Cinética , Modelos Teóricos
20.
Poult Sci ; 95(5): 1105-15, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26908887

RESUMO

Limitations in quality bedding material have resulted in the growing need to re-use litter during broiler farming in some countries, which can be of concern from a food-safety perspective. The aim of this study was to compare the Campylobacter levels in ceca and litter across three litter treatments under commercial farming conditions. The litter treatments were (a) the use of new litter after each farming cycle; (b) an Australian partial litter re-use practice; and (c) a full litter re-use practice. The study was carried out on two farms over two years (Farm 1, from 2009-2010 and Farm 2, from 2010-2011), across three sheds (35,000 to 40,000 chickens/shed) on each farm, adopting three different litter treatments across six commercial cycles. A random sampling design was adopted to test litter and ceca for Campylobacter and Escherichia coli, prior to commercial first thin-out and final pick-up. Campylobacter levels varied little across litter practices and farming cycles on each farm and were in the range of log 8.0-9.0 CFU/g in ceca and log 4.0-6.0 MPN/g for litter. Similarly the E. coli in ceca were ∼log 7.0 CFU/g. At first thin-out and final pick-up, the statistical analysis for both litter and ceca showed that the three-way interaction (treatments by farms by times) was highly significant (P<0.01), indicating that the patterns of Campylobacter emergence/presence across time vary between the farms, cycles and pickups. The emergence and levels of both organisms were not influenced by litter treatments across the six farming cycles on both farms. Either C. jejuni or C. coli could be the dominant species across litter and ceca, and this phenomenon could not be attributed to specific litter treatments. Irrespective of the litter treatments in place, cycle 2 on Farm 2 remained Campylobacter-free. These outcomes suggest that litter treatments did not directly influence the time of emergence and levels of Campylobacter and E. coli during commercial farming.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Galinhas , Infecções por Escherichia coli/veterinária , Escherichia coli/isolamento & purificação , Pisos e Cobertura de Pisos , Animais , Infecções por Campylobacter/microbiologia , Ceco/microbiologia , Microbiologia Ambiental , Infecções por Escherichia coli/microbiologia , Abrigo para Animais , Doenças das Aves Domésticas/microbiologia
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