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1.
Br J Nutr ; 127(12): 1774-1777, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35492026

RESUMO

The paper by K. L. Blaxter and J. L. Clapperton (1965) 'Prediction of the amount of methane produced by ruminants. Br J Nutr 19, 511-522' has been cited 656 times according to Web of Science and continues to be cited with increasing frequency to the present day. The analysis described in the paper, or meta-analysis as it would be known now, is of methane production from cattle and sheep based on forty-eight trials using closed-circuit respiration chambers, all carried out at the Hannah Research Institute, Ayr, UK, between 1955 and 1965. Methane emissions per unit of diet fed were shown to vary depending on diet, level of feeding and individual animal. As such, previous notions that methane emissions were essentially proportional to energy intake were set aside. The main reasons for the paper's continuing citation are the set of equations that can be used to predict methane emissions from ruminants when the technically demanding respiration chambers are unavailable, and that it was the first definitive study to describe the complexities of methane emissions with respect to animals and diets. The paper thus provided abundant insights of the relations between ruminant methane emissions and nutritional biology, and rumen microbiology, in particular, that have informed countless research projects in the intervening half-century. Given the importance of methane as a greenhouse gas in the climate change scenario, these insights are at least as relevant today as they were in 1965.


Assuntos
Gases de Efeito Estufa , Metano , Bovinos , Ovinos , Animais , Metano/análise , Ruminantes , Dieta/veterinária , Ingestão de Energia , Gases de Efeito Estufa/análise , Rúmen/química , Ração Animal/análise
2.
Appl Opt ; 61(8): 1987-1993, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35297891

RESUMO

Warm dense matter is a region of phase space that is of high interest to multiple scientific communities ranging from astrophysics to inertial confinement fusion. Further understanding of the conditions and properties of this complex state of matter necessitates experimental benchmarking of the current theoretical models. We discuss the development of an x-ray radiography platform designed to measure warm dense matter transport properties at large laser facilities such as the OMEGA Laser Facility. Our platform, Fresnel diffractive radiography, allows for high spatial resolution imaging of isochorically heated targets, resulting in notable diffractive effects at sharp density gradients that are influenced by transport properties such as thermal conductivity. We discuss initial results, highlighting the capabilities of the platform in measuring diffractive features with micrometer-level spatial resolution.

3.
Ann Oncol ; 32(7): 917-925, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33798657

RESUMO

BACKGROUND: Immune-related adverse events (irAEs) typically occur within 4 months of starting anti-programmed cell death protein 1 (PD-1)-based therapy [anti-PD-1 ± anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4)], but delayed irAEs (onset >12 months after commencement) can also occur. This study describes the incidence, nature and management of delayed irAEs in patients receiving anti-PD-1-based immunotherapy. PATIENTS AND METHODS: Patients with delayed irAEs from 20 centres were studied. The incidence of delayed irAEs was estimated as a proportion of melanoma patients treated with anti-PD-1-based therapy and surviving >1 year. Onset, clinical features, management and outcomes of irAEs were examined. RESULTS: One hundred and eighteen patients developed a total of 140 delayed irAEs (20 after initial combination with anti-CTLA4), with an estimated incidence of 5.3% (95% confidence interval 4.0-6.9, 53/999 patients at sites with available data). The median onset of delayed irAE was 16 months (range 12-53 months). Eighty-seven patients (74%) were on anti-PD-1 at irAE onset, 15 patients (12%) were <3 months from the last dose and 16 patients (14%) were >3 months from the last dose of anti-PD-1. The most common delayed irAEs were colitis, rash and pneumonitis; 55 of all irAEs (39%) were ≥grade 3. Steroids were required in 80 patients (68%), as well as an additional immunosuppressive agent in 27 patients (23%). There were two irAE-related deaths: encephalitis with onset during anti-PD-1 and a multiple-organ irAE with onset 11 months after ceasing anti-PD-1. Early irAEs (<12 months) had also occurred in 69 patients (58%), affecting a different organ from the delayed irAE in 59 patients (86%). CONCLUSIONS: Delayed irAEs occur in a small but relevant subset of patients. Delayed irAEs are often different from previous irAEs, may be high grade and can lead to death. They mostly occur in patients still receiving anti-PD-1. The risk of delayed irAE should be considered when deciding the duration of treatment in responding patients. However, patients who stop treatment may also rarely develop delayed irAE.


Assuntos
Melanoma , Pneumonia , Humanos , Fatores Imunológicos , Imunoterapia/efeitos adversos , Melanoma/tratamento farmacológico , Estudos Retrospectivos
4.
Hum Reprod ; 36(7): 1999-2010, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34021356

RESUMO

STUDY QUESTION: Does the expansion of genome-wide association studies (GWAS) to a broader range of ancestries improve the ability to identify and generalise variants associated with age at menarche (AAM) in European populations to a wider range of world populations? SUMMARY ANSWER: By including women with diverse and predominantly non-European ancestry in a large-scale meta-analysis of AAM with half of the women being of African ancestry, we identified a new locus associated with AAM in African-ancestry participants, and generalised loci from GWAS of European ancestry individuals. WHAT IS KNOWN ALREADY: AAM is a highly polygenic puberty trait associated with various diseases later in life. Both AAM and diseases associated with puberty timing vary by race or ethnicity. The majority of GWAS of AAM have been performed in European ancestry women. STUDY DESIGN, SIZE, DURATION: We analysed a total of 38 546 women who did not have predominantly European ancestry backgrounds: 25 149 women from seven studies from the ReproGen Consortium and 13 397 women from the UK Biobank. In addition, we used an independent sample of 5148 African-ancestry women from the Southern Community Cohort Study (SCCS) for replication. PARTICIPANTS/MATERIALS, SETTING, METHODS: Each AAM GWAS was performed by study and ancestry or ethnic group using linear regression models adjusted for birth year and study-specific covariates. ReproGen and UK Biobank results were meta-analysed using an inverse variance-weighted average method. A trans-ethnic meta-analysis was also carried out to assess heterogeneity due to different ancestry. MAIN RESULTS AND THE ROLE OF CHANCE: We observed consistent direction and effect sizes between our meta-analysis and the largest GWAS conducted in European or Asian ancestry women. We validated four AAM loci (1p31, 6q16, 6q22 and 9q31) with common genetic variants at P < 5 × 10-7. We detected one new association (10p15) at P < 5 × 10-8 with a low-frequency genetic variant lying in AKR1C4, which was replicated in an independent sample. This gene belongs to a family of enzymes that regulate the metabolism of steroid hormones and have been implicated in the pathophysiology of uterine diseases. The genetic variant in the new locus is more frequent in African-ancestry participants, and has a very low frequency in Asian or European-ancestry individuals. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Extreme AAM (<9 years or >18 years) were excluded from analysis. Women may not fully recall their AAM as most of the studies were conducted many years later. Further studies in women with diverse and predominantly non-European ancestry are needed to confirm and extend these findings, but the availability of such replication samples is limited. WIDER IMPLICATIONS OF THE FINDINGS: Expanding association studies to a broader range of ancestries or ethnicities may improve the identification of new genetic variants associated with complex diseases or traits and the generalisation of variants from European-ancestry studies to a wider range of world populations. STUDY FUNDING/COMPETING INTEREST(S): Funding was provided by CHARGE Consortium grant R01HL105756-07: Gene Discovery For CVD and Aging Phenotypes and by the NIH grant U24AG051129 awarded by the National Institute on Aging (NIA). The authors have no conflict of interest to declare.


Assuntos
Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Adolescente , Estudos de Coortes , Etnicidade , Feminino , Humanos , Menarca/genética
5.
J Dairy Sci ; 104(8): 8765-8782, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33896643

RESUMO

Predicting dry matter intake (DMI) and feed efficiency by leveraging the use of data streams available on farm could aid efforts to improve the feed efficiency of dairy cattle. Residual feed intake (RFI) is the difference between predicted and observed feed intake after accounting for body size, body weight change, and milk production, making it a valuable metric for feed efficiency research. Our objective was to develop and evaluate DMI and RFI prediction models using multiple linear regression (MLR), partial least squares regression, artificial neural networks, and stacked ensembles using different combinations of cow descriptive, performance, sensor-derived behavioral (SMARTBOW; Zoetis), and blood metabolite data. Data were collected from mid-lactation Holstein cows (n = 124; 102 multiparous, 22 primiparous) split equally between 2 replicates of 45-d duration with ad libitum access to feed. Within each predictive approach, 4 data streams were added in sequence: dataset M (week of lactation, parity, milk yield, and milk components), dataset MB (dataset M plus body condition score and metabolic body weight), dataset MBS (dataset MB plus sensor-derived behavioral variables), and dataset MBSP (dataset MBS plus physiological blood metabolites). The combination of 4 datasets and 4 analytical approaches resulted in 16 analyses of DMI and RFI, using variables averaged within cow across the study period. Additional models using weekly averaged data within cow and study were built using all predictive approaches for datasets M, MB, and MBS. Model performance was assessed using the coefficient of determination, concordance correlation coefficient, and root mean square error of prediction. Predictive models of DMI performed similarly across all approaches, and models using dataset MBS had the greatest model performance. The best approach-dataset combination was MLR-dataset MBS, although several models performed similarly. Weekly DMI models had the greatest performance with MLR and partial least squares regression approaches. Dataset MBS models had incrementally better performance than datasets MB and M. Within each approach-dataset combination, models with DMI averaged over the study period had slightly greater model performance than DMI averaged weekly. Predictive performance of all RFI models was poor, but slight improvements when using MLR applied to dataset MBS suggest that rumination and activity behaviors may explain some of the variation in RFI. Overall, similar performance of MLR, compared with machine learning techniques, indicates MLR may be sufficient to predict DMI. The improvement in model performance with each additional data stream supports the idea of integrating data streams to improve model predictions and farm management decisions.


Assuntos
Ração Animal , Lactação , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta/veterinária , Ingestão de Alimentos , Feminino , Leite , Gravidez
6.
Phys Rev Lett ; 124(2): 025003, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004037

RESUMO

We present a study on the impact of a gas atmosphere on the collision of two counterpropagating plasmas (gold and carbon). Imaging optical Thomson scattering data of the plasma collision with and without helium in between have been obtained at the Omega laser facility. Without gas, we observed large scale mixing of colliding gold and carbon ions. Once ambient helium is added, the two plasmas remain separated. The difference in ionic temperature is consistent with a reduction of the maximum Mach number of the flow from M=7 to M=4. It results in a reduction of a factor ∼10 of the counterstreaming ion-ion mean free path. By adding a low-density ambient gas, it is possible to control the collision of two high-velocity counterstreaming plasma, transitioning from an interpenetrating regime to a regime in agreement with a hydrodynamic description.

7.
Nanotechnology ; 31(5): 055704, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31618710

RESUMO

The atomic layer deposition (ALD) of high-k dielectrics could build an efficient barrier against moisture and O2 adsorption. Such a barrier is highly needed for MoTe2 and WTe2 transition metal dichalcogenides because of the poor structural stability and the fast oxidization in ambient air. In situ x-ray photoelectron spectroscopy and ex situ atomic force microscopy and scanning transmission electron microscopy were employed to report a comparative study between the growth of Al2O3 on MoTe2 and WTe2 by means of traditional thermal ALD and plasma-enhanced ALD (PEALD). Similar to what has been observed on other 2D materials such as MoS2 and Graphene, the thermal ALD results in an islanding growth of Al2O3 on MoTe2 due to the dearth of dangling bonds, whereas, a uniform coverage of Al2O3 on WTe2 is observed and likely contributed to the high concentration of intrinsic structural defects. The PEALD behavior is consistent between MoTe2 and WTe2 providing a conformal and linear growth rate (∼0.08 nm/cycle), which correlates with the creation of Te-O and metal-O nucleation sites. However, a thin layer of interfacial Mo or W oxides gradually forms, resulting from the plasma-induced damage in the topmost (1-2) layers. Attempts to enhance the Al2O3/MoTe2 interfacial quality by physically evaporating an Al2O3 seed layer are investigated as well. However, the evaporated Al2O3 process causes thermal damage on MoTe2, necessitating a more 'gentle' ALD technique for the surface passivation.

8.
Diabet Med ; 36(9): 1149-1157, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30552780

RESUMO

AIMS: To examine (1) the prevalence of depressive symptoms in women with Type 2 diabetes, (2) the associations between depressive symptoms and the following dependent variables: sleep disturbance; physical activity; physical health-related; and global quality of life, and (3) the potential moderating effects of antidepressants and optimism on the relationship between depressive symptoms and dependent variables. METHODS: Participants in the Women's Health Initiative who had Type 2 diabetes and data on depressive symptoms (N=8895) were included in the analyses. In multivariable linear regression models controlling for sociodemographic, medical and psychosocial covariates, we examined the main effect of depressive symptoms, as well as the interactions between depressive symptoms and antidepressant use, and between depressive symptoms and optimism, on sleep disturbance, physical activity, physical health-related quality of life; and global quality of life. RESULTS: In all, 16% of women with Type 2 diabetes reported elevated depressive symptoms. In multivariable analyses, women with depressive symptoms had greater sleep disturbance (P<0.0001) and lower global quality of life (P<.0001). We found evidence of significant statistical interaction in the models for quality-of-life outcomes: the increased risk of poor physical health-related quality of life associated with antidepressant use was stronger in women without vs with depressive symptoms, and the association between greater optimism and higher global quality of life was stronger in women with vs without depressive symptoms. CONCLUSIONS: To improve health behaviours and quality of life in women with Type 2 diabetes, sociodemographic and medical characteristics may identify at-risk populations, while psychosocial factors including depression and optimism may be important targets for non-pharmacological intervention.


Assuntos
Depressão/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Exercício Físico/fisiologia , Qualidade de Vida , Transtornos do Sono-Vigília/epidemiologia , Idoso , Antidepressivos/uso terapêutico , Depressão/complicações , Depressão/tratamento farmacológico , Depressão/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/psicologia , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/complicações , Fatores Socioeconômicos , Inquéritos e Questionários , Estados Unidos/epidemiologia
9.
Epidemiol Infect ; 147: e247, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364582

RESUMO

Dogs harbor numerous zoonotic pathogens, many of which are controlled through vaccination programs. The delivery of these programs can be difficult where resources are limited. We developed a dynamic model to estimate vaccination coverage and cost-per-dog vaccinated. The model considers the main factors that affect vaccination programs: dog demographics, effectiveness of strategies, efficacy of interventions and cost. The model was evaluated on data from 18 vaccination programs representing eight countries. Sensitivity analysis was performed for dog confinement and vaccination strategies. The average difference between modelled vaccination coverage and field data was 3.8% (2.3%-5.3%). Central point vaccination was the most cost-effective vaccination strategy when >88% of the dog population was confined. More active methods of vaccination, such as door-to-door or capture-vaccinate-release, achieved higher vaccination coverage in free-roaming dog populations but were more costly. This open-access tool can aid in planning more efficient vaccination campaigns in countries with limited resources.


Assuntos
Vacinação em Massa/veterinária , Vacina Antirrábica/administração & dosagem , Raiva/prevenção & controle , Cobertura Vacinal/economia , Vacinação/estatística & dados numéricos , África Oriental , África do Norte , Animais , Ásia , América Central , Análise Custo-Benefício , Cães , Humanos , Vacinação em Massa/economia , América do Norte , Raiva/epidemiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vacinação/economia
10.
J Appl Microbiol ; 127(2): 586-597, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31077510

RESUMO

AIMS: The current study aimed to assess the potential of a new high dose ultraviolet (UV) disinfection device to inactivate methicillin-resistant Staphylococcus aureus (MRSA), Clostridium difficile and a norovirus surrogate on handheld mobile devices, and to compare the efficacy of the UV-C device to hydrogen peroxide disinfection wipes. METHODS AND RESULTS: Suspensions of MRSA, C. difficile spores and a surrogate for norovirus (MS2) were inoculated onto glass or plastic coupons, with or without organic contamination and were exposed to continuous UV-C light for 15-60 s (165-646 mJ cm-2 ) in a self-contained UV-C chamber or treated with hydrogen peroxide wipes. Increasing the UV-C dose from 310 to 650 mJ cm-2 did not result in greater levels of inactivation. UV-C light inactivated all three micro-organisms, in the absence of organic contamination, by >2·9 log. Treatment of MRSA, C. difficile spores or MS2, in the presence of organic contamination, with UV-C light (310-646 mJ cm-2 ) resulted in 2·3-3·7 log reductions. Treatment of MRSA with UV-C light provided levels of inactivation comparable to treatment with hydrogen peroxide wipes used following the manufacturer's instructions. CONCLUSIONS: UV-C light and hydrogen peroxide wipes had strong antimicrobial activity against MRSA, C. difficile spores and a norovirus surrogate, in the presence or absence of organic contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: Chemical disinfection wipes are widely used in healthcare facilities, but they are not recommended for use on handheld mobile devices which may harbour pathogenic micro-organisms. The powerful bactericidal, sporicidal and virucidal activity of this high dose UV-C light device, shows that this technology is a promising alternative to chemical disinfectants, particularly for control of MRSA.


Assuntos
Clostridioides difficile/efeitos da radiação , Desinfecção , Staphylococcus aureus Resistente à Meticilina/efeitos da radiação , Norovirus/efeitos da radiação , Raios Ultravioleta , Clostridioides difficile/efeitos dos fármacos , Desinfetantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Norovirus/efeitos dos fármacos , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/efeitos da radiação
11.
PLoS Genet ; 12(2): e1005846, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26891056

RESUMO

Methane produced by methanogenic archaea in ruminants contributes significantly to anthropogenic greenhouse gas emissions. The host genetic link controlling microbial methane production is unknown and appropriate genetic selection strategies are not developed. We used sire progeny group differences to estimate the host genetic influence on rumen microbial methane production in a factorial experiment consisting of crossbred breed types and diets. Rumen metagenomic profiling was undertaken to investigate links between microbial genes and methane emissions or feed conversion efficiency. Sire progeny groups differed significantly in their methane emissions measured in respiration chambers. Ranking of the sire progeny groups based on methane emissions or relative archaeal abundance was consistent overall and within diet, suggesting that archaeal abundance in ruminal digesta is under host genetic control and can be used to genetically select animals without measuring methane directly. In the metagenomic analysis of rumen contents, we identified 3970 microbial genes of which 20 and 49 genes were significantly associated with methane emissions and feed conversion efficiency respectively. These explained 81% and 86% of the respective variation and were clustered in distinct functional gene networks. Methanogenesis genes (e.g. mcrA and fmdB) were associated with methane emissions, whilst host-microbiome cross talk genes (e.g. TSTA3 and FucI) were associated with feed conversion efficiency. These results strengthen the idea that the host animal controls its own microbiota to a significant extent and open up the implementation of effective breeding strategies using rumen microbial gene abundance as a predictor for difficult-to-measure traits on a large number of hosts. Generally, the results provide a proof of principle to use the relative abundance of microbial genes in the gastrointestinal tract of different species to predict their influence on traits e.g. human metabolism, health and behaviour, as well as to understand the genetic link between host and microbiome.


Assuntos
Variação Genética , Metano/metabolismo , Microbiota/fisiologia , Rúmen/microbiologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Archaea/genética , Archaea/metabolismo , Bovinos , Feminino , Masculino , Metagenômica/métodos , Microbiota/genética
12.
Ann Oncol ; 29(8): 1869-1876, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29912274

RESUMO

Background: Alterations involving the RET kinase are implicated in the pathogenesis of lung, thyroid and other cancers. However, the clinical activity of multikinase inhibitors (MKIs) with anti-RET activity in RET-altered patients appears limited, calling into question the therapeutic potential of targeting RET. LOXO-292 is a selective RET inhibitor designed to inhibit diverse RET fusions, activating mutations and acquired resistance mutations. Patients and methods: Potent anti-RET activity, high selectivity, and central nervous system coverage were confirmed preclinically using a variety of in vitro and in vivo RET-dependent tumor models. Due to clinical urgency, two patients with RET-altered, MKI-resistant cancers were treated with LOXO-292, utilizing rapid dose-titration guided by real-time pharmacokinetic assessments to achieve meaningful clinical exposures safely and rapidly. Results: LOXO-292 demonstrated potent and selective anti-RET activity preclinically against human cancer cell lines harboring endogenous RET gene alterations; cells engineered to express a KIF5B-RET fusion protein -/+ the RET V804M gatekeeper resistance mutation or the common RET activating mutation M918T; and RET-altered human cancer cell line and patient-derived xenografts, including a patient-derived RET fusion-positive xenograft injected orthotopically into the brain. A patient with RET M918T-mutant medullary thyroid cancer metastatic to the liver and an acquired RET V804M gatekeeper resistance mutation, previously treated with six MKI regimens, experienced rapid reductions in tumor calcitonin, CEA and cell-free DNA, resolution of painful hepatomegaly and tumor-related diarrhea and a confirmed tumor response. A second patient with KIF5B-RET fusion-positive lung cancer, acquired resistance to alectinib and symptomatic brain metastases experienced a dramatic response in the brain, and her symptoms resolved. Conclusions: These results provide proof-of-concept of the clinical actionability of RET alterations, and identify selective RET inhibition by LOXO-292 as a promising treatment in heavily pretreated, multikinase inhibitor-experienced patients with diverse RET-altered tumors.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Carcinoma Neuroendócrino/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Adulto , Neoplasias Encefálicas/secundário , Carbazóis/farmacologia , Carbazóis/uso terapêutico , Carcinoma Neuroendócrino/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Proteínas de Fusão Oncogênica/genética , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Estudo de Prova de Conceito , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-ret/genética , Pirazóis/farmacologia , Piridinas/farmacologia , Neoplasias da Glândula Tireoide/patologia , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Dairy Sci ; 101(4): 3021-3035, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29428753

RESUMO

Fish oil (FO) alters ruminal biohydrogenation causing trans fatty acid (FA) intermediates to accumulate, but the effects of 18-carbon polyunsaturated FA supply on ruminal long-chain FA metabolism and microbial communities in cattle fed FO are not well established. Four cows fitted with rumen cannula were used in a 4 × 4 Latin square with 21-d experimental periods to evaluate the effects of FO alone or in combination with plant oils high in 18:2n-6 or 18:3n-3 on rumen microbial ecology and flow of FA at the omasum. Treatments comprised a basal grass silage-based diet containing no additional oil (control) or supplements of FO (200 g/d) or FO (200 g/d) plus 500 g/d of sunflower oil (SFO) or linseed oil (LFO). Flow of FA was determined using the omasal sampling technique. The relative abundance of key biohydrogenating bacteria was assessed by quantitative PCR on 16S rRNA genes in omasal digesta. Fish oil-supplemented treatments increased the amounts of trans-18:1, trans-18:2, and 20- to 22-carbon polyunsaturated FA escaping the rumen. Relative to the control, oil supplements had no effect on the amount of 18:0 leaving the rumen, but LFO decreased the flow of 18:0 at the omasum compared with SFO. Both SFO and LFO increased trans-18:1 relative to FO, whereas LFO resulted in the highest trans-18:2 and 20- to 22-carbon FA flow. Supplements of FO plus plant oils shifted biohydrogenation toward trans-10 18:1 formation. Compared with FO alone, the ruminal metabolism of 22:6n-3 in the rumen of lactating cows is more extensive on diets containing higher amounts of 18-carbon polyunsaturated FA. However, the biohydrogenation of 22:5n-3 was less extensive in LFO than SFO, but showed no difference between FO and diets containing plant oils. Ruminal outflow of 20:5n-3 was not altered when plant oils were added to FO. Alterations in the amount of intermediates at the omasum or ruminal biohydrogenation pathways were not accompanied by major changes in analyzed bacterial populations. In conclusion, dietary supplements of FO alone or in combination with plant oils increase the amount of biohydrogenation intermediates containing 1 or more trans double bonds escaping the rumen, which may have implications for host metabolism and the nutritional quality of ruminant foods.


Assuntos
Bovinos/metabolismo , Bovinos/microbiologia , Óleos de Peixe/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Óleo de Semente do Linho/metabolismo , Metabolismo dos Lipídeos , Óleo de Girassol/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Ácidos Graxos/análise , Feminino , Óleos de Peixe/administração & dosagem , Lactação , Óleo de Semente do Linho/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Omaso/metabolismo , Rúmen/efeitos dos fármacos , Rúmen/metabolismo , Rúmen/microbiologia , Óleo de Girassol/administração & dosagem
14.
Rev Sci Tech ; 37(2): 359-370, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30747142

RESUMO

Effective real-time surveillance, combined with proficient, decentralised and validated laboratory diagnostics, is a prerequisite for successful rabies control and elimination. The selection and prioritisation of surveillance methodologies, in conjunction with appropriate diagnostic techniques, should reflect the goals of the disease control and elimination programme (Stage 1: proof of burden; Stage 2: human rabies prevention; Stage 3: monitoring and assessment of control measures; Stage 4: verification of rabies elimination; and Stage 5: post elimination). The development of minimum surveillance requirements, in accordance with Chapter 1.4 of the World Organisation for Animal Health Terrestrial Animal Health Code, and routine evaluation of disease elimination indicators are of the utmost importance if the goal of eliminating dog-mediated human rabies by 2030 is to be achieved.


Une surveillance efficace en temps réel soutenue par des tests diagnostiques performants et validés réalisés par des laboratoires décentralisés est une condition préalable pour que les efforts de contrôle et d'élimination de la rage soient couronnés de succès. Le choix et la priorisation des méthodes de surveillance et des techniques diagnostiques qui leur sont associées doivent tenir compte des objectifs du programme de lutte et d'élimination de la rage (phase 1 : détermination de la charge induite par la maladie ; phase 2 : prévention de la rage humaine ; phase 3 : suivi et évaluation des mesures de lutte ; phase 4 : vérification de l'absence de rage ; phase 5 : post-élimination). Il est essentiel d'élaborer des mesures minimales de surveillance en conformité avec les dispositions du chapitre 1.4. du Code sanitaire pour les animaux terrestres de l'Organisation mondiale de la santé animale et de procéder à une évaluation systématique des indicateurs de l'élimination de la maladie si l'on veut atteindre l'objectif de l'élimination de la rage humaine transmise par les chiens d'ici 2030.


Para que las actividades de control y eliminación de la rabia culminen con éxito es requisito previo e indispensable una vigilancia eficaz en tiempo real, combinada con una labor competente y descentralizada de diagnósticos de laboratorio validados. La selección y jerarquización de los métodos de vigilancia, junto con el uso de técnicas apropiadas de diagnóstico, deben responder a los objetivos marcados en el programa de control y eliminación de la enfermedad (fase 1: datos demostrativos de la carga de enfermedad; fase 2: prevención de la rabia humana; fase 3: seguimiento y evaluación de las medidas de control; fase 4: verificación de la eliminación de la rabia; y fase 5: periodo posterior a la eliminación). La definición de requisitos mínimos de vigilancia, de conformidad con el capítulo 1.4. del Código Sanitario para los Animales Terrestres de la Organización Mundial de Sanidad Animal (OIE), así como la evaluación sistemática de indicadores relativos a la eliminación de la enfermedad, revisten la mayor importancia para que se cumpla el objetivo de haber eliminado la rabia transmitida por perros para 2030.


Assuntos
Erradicação de Doenças/métodos , Doenças do Cão/prevenção & controle , Vacina Antirrábica/imunologia , Raiva/veterinária , Animais , Países em Desenvolvimento , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Humanos , Cooperação Internacional , Raiva/prevenção & controle
15.
BMC Microbiol ; 17(1): 9, 2017 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-28061817

RESUMO

BACKGROUND: Ruminal digestion is carried out by large numbers of bacteria, archaea, protozoa and fungi. Understanding the microbiota is important because ruminal fermentation dictates the efficiency of feed utilisation by the animal and is also responsible for major emissions of the greenhouse gas, methane. Recent metagenomic and metatranscriptomic studies have helped to elucidate many features of the composition and activity of the microbiota. The metaproteome provides complementary information to these other -omics technologies. The aim of this study was to explore the metaproteome of bovine and ovine ruminal digesta using 2D SDS-PAGE. RESULTS: Digesta samples were taken via ruminal fistulae and by gastric intubation, or at slaughter, and stored in glycerol at -80 °C. A protein extraction protocol was developed to maximise yield and representativeness of the protein content. The proteome of ruminal digesta taken from dairy cows fed a high concentrate diet was dominated by a few very highly expressed proteins, which were identified by LC-MS/MS to be structural proteins, such as actin and α- and ß-tubulins, derived from ciliate protozoa. Removal of protozoa from digesta before extraction of proteins revealed the prokaryotic metaproteome, which was dominated by enzymes involved in glycolysis, such as glyceraldehyde-3-phosphate dehydrogenase, phosphoenolpyruvate carboxykinase, phosphoglycerate kinase and triosephosphate isomerase. The enzymes were predominantly from the Firmicutes and Bacteroidetes phyla. Enzymes from methanogenic archaea were also abundant, consistent with the importance of methane formation in the rumen. Gels from samples from dairy cows fed a high proportion of grass silage were consistently obscured by co-staining of humic compounds. Samples from beef cattle and fattening lambs receiving a predominantly concentrate diet produced clearer gels, but the pattern of spots was inconsistent between samples, making comparisons difficult. CONCLUSION: This work demonstrated for the first time that 2D-PAGE reveals key structural proteins and enzymes in the rumen microbial community, despite its high complexity, and that taxonomic information can be deduced from the analysis. However, technical issues associated with feed material contamination, which affects the reproducibility of electrophoresis of different samples, limits its value.


Assuntos
Bovinos/microbiologia , Eletroforese em Gel de Poliacrilamida/métodos , Metagenômica/métodos , Microbiota/genética , Rúmen/metabolismo , Rúmen/microbiologia , Ovinos/microbiologia , Ração Animal/análise , Animais , Archaea/enzimologia , Archaea/metabolismo , Bactérias/enzimologia , Bactérias/metabolismo , Dieta/veterinária , Digestão , Fermentação , Finlândia , Poaceae , Reprodutibilidade dos Testes , Escócia , Silagem , Suécia , Espectrometria de Massas em Tandem
16.
Epidemiol Infect ; 145(8): 1624-1634, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28290915

RESUMO

Haiti has the highest human rabies burden in the Western Hemisphere. There is no published literature describing the public's perceptions of rabies in Haiti, information that is critical to developing effective interventions and government policies. We conducted a knowledge, attitudes and practices survey of 550 community members and 116 health professionals in Pétionville, Haiti in 2013 to understand the perception of rabies in these populations. The majority of respondents (85%) knew that dogs were the primary reservoir for rabies, yet only 1% were aware that bats and mongooses could transmit rabies. Animal bites were recognized as a mechanism of rabies transmission by 77% of the population and 76% were aware that the disease could be prevented by vaccination. Of 172 persons reporting a bite, only 37% sought medical treatment. The annual bite incidence rate in respondents was 0·9%. Only 31% of bite victims reported that they started the rabies vaccination series. Only 38% of respondents reported that their dog had been vaccinated against rabies. The majority of medical professionals recognized that dogs were the main reservoir for rabies (98%), but only 28% reported bats and 14% reported mongooses as posing a risk for rabies infection. Bites were reported as a mechanism of rabies transmission by 73% of respondents; exposure to saliva was reported by 20%. Thirty-four percent of medical professionals reported they would wash a bite wound with soap and water and 2·8% specifically mentioned rabies vaccination as a component of post-bite treatment. The majority of healthcare professionals recommended some form of rabies assessment for biting animals; 68·9% recommended a 14-day observation period, 60·4% recommended a veterinary consultation, and 13·2% recommended checking the vaccination status of the animal. Fewer than 15% of healthcare professionals had ever received training on rabies prevention and 77% did not know where to go to procure rabies vaccine for bite victims. Both study populations had a high level of knowledge about the primary reservoir for rabies and the mode of transmission. However, there is a need to improve the level of knowledge regarding the importance of seeking medical care for dog bites and additional training on rabies prevention for healthcare professionals. Distribution channels for rabies vaccines should be evaluated, as the majority of healthcare providers did not know where rabies vaccines could be obtained. Canine rabies vaccination is the primary intervention for rabies control programmes, yet most owned dogs in this population were not vaccinated.


Assuntos
Competência Clínica , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/psicologia , Raiva/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Haiti , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Adulto Jovem
17.
J Clin Pharm Ther ; 42(1): 27-38, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28019014

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Although non-steroidal anti-inflammatory drugs (NSAIDs) have been studied in randomized, controlled trials and meta-analyses in an effort to determine their cardiovascular (CV) risks, no consensus has been reached. These studies continue to raise questions, including whether cyclooxygenase-2 (COX-2) selectivity plays a role in conferring CV risk. We performed a meta-analysis of current literature to determine whether COX-2 selectivity leads to an increased CV risk. METHODS: We utilized randomized, controlled trials and prospective cohort studies. We selected eight NSAIDs based on popularity and COX selectivity and conducted a search of the MEDLINE, EMBASE, and Cochrane databases. Primary endpoints included any myocardial infarction (MI), any stroke, CV death, and a combination of all three (composite CV outcomes). Twenty-six studies were found that met inclusion and exclusion criteria. Comparisons were made between all included drugs, against placebo, and against non-selective NSAIDs (nsNSAIDs). Drugs were also compared against COX-2 selective inhibitors (COXIBs) with and without inclusion of rofecoxib. RESULTS AND DISCUSSION: Incidence of MI was increased by rofecoxib in all comparison categories [all NSAIDs (OR: 1·811, 95% CI: 1·379-2·378), placebo (OR: 1·655: 95% CI: 1·029-2·661), nsNSAIDs (OR: 2·155, 95% CI: 1·146-4·053), and COXIBs (OR: 1·800, 95% CI: 1·217-2·662)], but was decreased by celecoxib and naproxen in the COXIB comparison [(OR: 0·583, 95% CI: 0·396-0·857) and (OR: 0·609, 95% CI: 0·375-0·989, respectively]. Incidence of stroke was increased by rofecoxib in comparisons with all NSAIDs and other COXIBs [(OR: 1·488, 95% CI: 1·027-2·155) and (OR: 1·933, 95% CI: 1·052-3·549), respectively]. Incidence of stroke was decreased by celecoxib when compared with all NSAIDs, nsNSAIDs, and COXIBs [(OR: 0·603, 95% CI: 0·410-0·887), (OR: 0·517, 95% CI: 0·287-0·929), and (OR: 0·509, 95% CI: 0·280-0·925), respectively]. No NSAID reached statistical significance in regard to CV death. Incidence of the composite endpoint was increased by rofecoxib when compared against all NSAIDs, placebo, and other COXIBs [(OR: 1·612, 95% CI: 1·313-1·981), (OR: 1·572, 95% CI: 1·123-2·201) and (OR: 1·838, 95% CI: 1·323-2·554), respectively]. Incidence of composite endpoint was decreased by celecoxib in the all NSAIDs and COXIBs comparisons [(OR: 0·805, 95% CI: 0·658-0·986) and (OR: 0·557, 95% CI: 0.404-0.767), respectively]. When rofecoxib was removed from the COXIBs group, no difference was found with any comparison, suggesting rofecoxib skewed the data. WHAT IS NEW AND CONCLUSION: This instead of the meta-analysis suggests that COX-2 selectivity may not play a role in the CV risk of NSAIDs. Rofecoxib was the only drug to demonstrate harm and skewed the data of the COX-2 selective group.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco
19.
Br J Nutr ; 115(12): 2093-105, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27087357

RESUMO

Description of α-linolenic acid (cis-9,cis-12,cis-15-18 : 3, ALA) metabolism in the rumen is incomplete. Ruminal digesta samples were incubated with ALA and buffer containing water or deuterium oxide to investigate the products and mechanisms of ALA biohydrogenation. Geometric Δ9,11,15-18 : 3 isomers were the main intermediates formed from ALA. An increase in the n+1 isotopomers of Δ9,11,15-18 : 3 was due to 2H labelling at C-13. Isomers of Δ9,11,13-18 : 3, cis-7,cis-12,cis-15-18 : 3 and cis-8,cis-12,cis-15-18 : 3 were also formed. No increase in n+1 isotopomers of Δ7,12,15-18 : 3 or Δ8,12,15-18 : 3 was detected. Enrichment in n+2 isotopomers of 18 : 2 products indicated that ALA metabolism continued via the reduction of 18 : 3 intermediates. Isomers of Δ9,11,15-18 : 3 were reduced to Δ11,15-18 : 2 labelled at C-9 and C-13. ALA resulted in the formation of Δ11,13-18 : 2 and Δ12,14-18 : 2 containing multiple 2H labels. Enrichment of the n+3 isotopomer of Δ12,15-18 : 2 was also detected. Metabolism of ALA during incubations with rumen contents occurs by one of three distinct pathways. Formation of Δ9,11,15-18 : 3 appears to be initiated by H abstraction on C-13. Octadecatrienoic intermediates containing cis-12 and cis-15 double bonds are formed without an apparent H exchange with water. Labelling of Δ9,11,13-18 : 3 was inconclusive, suggesting formation by an alternative mechanism. These findings explain the appearance of several bioactive fatty acids in muscle and milk that influence the nutritional value of ruminant-derived foods.


Assuntos
Gorduras na Dieta/metabolismo , Digestão , Ácidos Linoleicos Conjugados/biossíntese , Leite/química , Músculos/química , Rúmen/metabolismo , Ácido alfa-Linolênico/metabolismo , Animais , Bovinos , Feminino , Hidrogenação , Isomerismo , Carne/análise , Ruminantes/metabolismo , Ácido alfa-Linolênico/análogos & derivados
20.
Avian Pathol ; 45(4): 393-407, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27009571

RESUMO

Avian malaria is a mosquito-borne disease caused by protozoans of the genus Plasmodium, and it is considered one of the most important causes of morbidity and mortality in captive penguins, both in zoological gardens and rehabilitation centres. Penguins are known to be highly susceptible to this disease, and outbreaks have been associated with mortality as high as 50-80% of affected captive populations within a few weeks. The disease has also been reported in wild penguin populations, however, its impacts on the health and fitness of penguins in the wild is not clear. This review provides an overview of the aetiology, life cycle and epidemiology of avian malaria, and provides details on the strategies that can be employed for the diagnostic, treatment and prevention of this disease in captive penguins, discussing possible directions for future research.


Assuntos
Malária Aviária/parasitologia , Plasmodium/fisiologia , Spheniscidae/parasitologia , Animais , Malária Aviária/diagnóstico , Malária Aviária/epidemiologia , Malária Aviária/prevenção & controle
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