RESUMO
Today, the eastern African hydroclimate is tightly linked to fluctuations in the zonal atmospheric Walker circulation1,2. A growing body of evidence indicates that this circulation shaped hydroclimatic conditions in the Indian Ocean region also on much longer, glacial-interglacial timescales3-5, following the development of Pacific Walker circulation around 2.2-2.0 million years ago (Ma)6,7. However, continuous long-term records to determine the timing and mechanisms of Pacific-influenced climate transitions in the Indian Ocean have been unavailable. Here we present a seven-million-year-long record of wind-driven circulation of the tropical Indian Ocean, as recorded in Mozambique Channel Throughflow (MCT) flow-speed variations. We show that the MCT flow speed was relatively weak and steady until 2.1 ± 0.1 Ma, when it began to increase, coincident with the intensification of the Pacific Walker circulation6,7. Strong increases during glacial periods, which reached maxima after the Mid-Pleistocene Transition (0.9-0.64 Ma; ref. 8), were punctuated by weak flow speeds during interglacial periods. We provide a mechanism explaining that increasing MCT flow speeds reflect synchronous development of the Indo-Pacific Walker cells that promote aridification in Africa. Our results suggest that after about 2.1 Ma, the increasing aridification is punctuated by pronounced humid interglacial periods. This record will facilitate testing of hypotheses of climate-environmental drivers for hominin evolution and dispersal.
RESUMO
There is world-wide increasing interest in the consumption of unprocessed, natural food commodities including fresh (unpasteurised) milk and milk products. Consumers are actively seeking out raw milk, partly due to health reasons, but also for taste, freshness, closeness to the producer and to support local agriculture. The need for high levels of hygiene and safety in farms producing raw milk for direct consumption has long been recognised and has led to federal and industry-initiated systems for safe raw milk production. Raw milk producers in North America and Europe have demonstrated that raw milk, intended for direct consumption, can be produced safe and hygienic. The aim of this paper is to describe practices that have been developed for safe raw milk production. The German Vorzugsmilch is a federally regulated programme for legal raw milk production that was established already in the 1930s to provide raw milk with high hygienic standards controlled for zoonotic diseases to consumers. The Raw Milk Institute is a non-profit organisation established in California that has developed a voluntary safe raw milk programme in North America. RAWMI has developed a risk analysis and management system for raw milk dairy farmers to assist farmers in making individually tailored solutions for various production systems. In British Colombia, Canada, small herd share farms have employed good manufacturing practices, a risk management approach and performed monthly samples for pathogens and indicator bacteria to demonstrate safety and consistency. The major components of the raw milk systems applied, and the results of regular milk microbial indicator bacteria are presented. For the German system, the results from standard monthly pathogen tests are compared to zoonotic pathogen tests from other milk sources. The overall results indicate that raw milk can be produced with a high level of hygiene and safety in various systems.
Assuntos
Indústria Alimentícia/métodos , Microbiologia de Alimentos/métodos , Microbiologia de Alimentos/normas , Inocuidade dos Alimentos/métodos , Leite/microbiologia , Animais , Doenças Transmitidas por Alimentos/prevenção & controle , Saúde Global , HumanosRESUMO
Horns are living tissue and cows can use their horns for thermoregulatory purposes. We investigated the effect of the presence of horns on the metabolome of milk serum and lipidome of milk fat, to assess the physiological effect of dehorning. Milk sampling took place at low ambient temperatures of -6 to 2°C. Horned and dehorned cows were kept in a mixed herd of Holstein Friesian and Brown Swiss cows. The hypothesis was that horned cows needed to increase their metabolism to compensate for additional heat loss through the presence of their horns. No differences were observed in milk yield, milk solids, and somatic cell counts between horned and dehorned cows. For the milk metabolome, horned cows showed an upregulation of several glucogenic AA that could be transformed into glucose for energy supply and a downregulation of sugar intermediates and γ-glutamylcysteine compared with dehorned cows. The fatty acid (FA) composition in horned cows showed a shift toward decreased odd medium-chain FA (C7:0, C9:0, and C11:0) and increased cis-vaccenic acid (C18:1n-7 cis-11) and stearidonic acid (C18:4n-3). The changes in milk composition related to additional heat loss in horned cows indicate a competition in C3 metabolism for glucose synthesis and de novo FA synthesis under cold stress.
Assuntos
Cornos/fisiologia , Metaboloma , Leite/química , Animais , Regulação da Temperatura Corporal , Metabolismo dos Carboidratos , Bovinos , Ácidos Graxos/metabolismo , Feminino , Cornos/cirurgia , Lactação/fisiologia , Ácidos Oleicos/metabolismoRESUMO
Background and aims: Hepatic steatosis is the basis of non-alcoholic fatty liver disease (NALFD). Mere fat accumulation within hepatocytes is considered the mild form of NAFLD, but can progress in some patients to advanced steatohepatitis (NASH), which may lead to fibrosis, cirrhosis or hepatocellular carcinoma. However, even hepatic steatosis alone may be a risk factor for cardiovascular disease (CVD). Patients and methods: In the present real life study 106 patients from the outpatient clinic of the Department for Gastroenterology and Hepatology with either NAFLD (nâ=â60) or other typical diagnoses (nâ=â46) were included. Ultrasound examination identified 77 patients with hepatic steatosis. Liver enzymes, lipid profile, surrogate cell death markers, and adiponectin were determined. Transient elastography (Fibroscan®) and bioelectrical impedance analysis (BIA) were performed. Results: Mean patient age was 46 years (23â-â62) for non-NAFLD and 53 years (18â-â71) for the NAFLD group.âALT and AST did not differ significantly between the two groups. Adiponectin and HDL were significantly lower in NAFLD (pâ<â0.05) and BIA profiles showed higher fat and fat free mass. Non-NAFLD patients with steatosis also exhibited an adverse metabolic profile. Overall steatosis was associated with factors of metabolic syndrome (MS) and CVD. Prevalence of CVD and factors of MS hint to steatosis as an early event for these conditions. Conclusion: Patients with steatosis are at higher cardiovascular and metabolic risk without differences in transaminases levels compared to those without steatosis. Steatosis diagnosed by ultrasound needs to rise attention for further metabolic alterations including CVD.
Assuntos
Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/epidemiologia , Síndrome Metabólica/diagnóstico por imagem , Síndrome Metabólica/epidemiologia , Ultrassonografia/estatística & dados numéricos , Adulto , Causalidade , Comorbidade , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e EspecificidadeRESUMO
The aims of this work were to elucidate the potential of using milk fatty acid (FA) concentration to predict cow diet composition and altitude of bulk milk collected in 10 different European countries and to authenticate cow-feeding systems and altitude of the production area using a data set of 1,248 bulk cow milk samples and associated farm records. The predictions based on FA for cow diet composition were excellent for the proportions of fresh herbage [coefficient of determination (R2)=0.81], good for hay, total herbage-derived forages, and total preserved forages (R2>0.73), intermediate for corn silage and grass silage (R2>0.62), and poor for concentrates (R2<0.51) in the cow diet. Milk samples were assigned to groups according to feeding system, level of concentrate supplementation, and altitude origin. Milk FA composition successfully authenticated cow-feeding systems dominated by a main forage (>93% of samples correctly classified), but the presence of mixed diets reduced the discrimination. Altitude prediction reliability was intermediate (R2<0.62). Milk FA composition was not able to authenticate concentrate supplementation level in the diet (<58% of samples correctly classified). Similarly, the altitude origin was not successfully authenticated by milk FA composition (<76% of samples correctly classified). The potential of milk FA composition to authenticate cow feeding was confirmed using a data set representative of the diversity of European production conditions.
Assuntos
Dieta/veterinária , Ácidos Graxos/análise , Leite/química , Silagem/análise , Altitude , Animais , Bovinos , Suplementos Nutricionais , Europa (Continente) , Poaceae , Reprodutibilidade dos Testes , Zea maysRESUMO
The aim of this study was to predict the fatty acid (FA) composition of bulk milk using data describing farming practices collected via on-farm surveys. The FA composition of 1,248 bulk cow milk samples and the related farming practices were collected from 20 experiments led in 10 different European countries at 44°N to 60°N latitude and sea level to 2,000 m altitude. Farming practice-based FA predictions [coefficient of determination (R(2)) >0.50] were good for C16:0, C17:0, saturated FA, polyunsaturated FA, and odd-chain FA, and very good (R(2) ≥0.60) for trans-11 C18:1, trans-10 + trans-11 C18:1, cis-9,trans-11 conjugated linoleic acid, total trans FA, C18:3n-3, n-6:n-3 ratio, and branched-chain FA. Fatty acids were predicted by cow diet composition and by the altitude at which milk was produced, whereas animal-related factors (i.e., lactation stage, breed, milk yield, and proportion of primiparous cows in the herd) were not significant in any of the models. Proportion of fresh herbage in the cow diet was the main predictor, with the highest effect in almost all FA models. However, models built solely on conserved forage-derived samples gave good predictions for odd-chain FA, branched-chain FA, trans-10 C18:1 and C18:3n-3 (R(2) ≥0.46, 0.54, 0.52, and 0.70, respectively). These prediction models could offer farmers a valuable tool to help improve the nutritional quality of the milk they produce.
Assuntos
Agricultura/métodos , Dieta/veterinária , Ácidos Graxos/análise , Leite/química , Altitude , Animais , Bovinos , Europa (Continente) , Ácidos Graxos Insaturados/análise , Feminino , Lactação , Ácidos Linoleicos Conjugados/análise , Valor Nutritivo , Poaceae , Silagem , Zea maysRESUMO
SMNrp, also termed SPF30, has recently been identified in spliceosomes assembled in vitro. We have functionally characterized this protein and show that it is an essential splicing factor. We show that SMNrp is a 17S U2 snRNP-associated protein that appears in the pre-spliceosome (complex A) and the mature spliceosome (complex B) during splicing. Immunodepletion of SMNrp from nuclear extract inhibits the first step of pre-mRNA splicing by preventing the formation of complex B. Re-addition of recombinant SMNrp to immunodepleted extract reconstitutes both spliceosome formation and splicing. Mutations in two domains of SMNrp, although similarly deleterious for splicing, differed in their consequences on U2 snRNP binding, suggesting that SMNrp may also engage in interactions with splicing factors other than the U2 snRNP. In agreement with this, we present evidence for an additional interaction between SMNrp and the [U4/U6.U5] tri-snRNP. A candidate that may mediate this interaction, namely the U4/U6-90 kDa protein, has been identified. We suggest that SMNrp, as a U2 snRNP-associated protein, facilitates the recruitment of the [U4/U6.U5] tri-snRNP to the pre-spliceosome.
Assuntos
Proteínas do Tecido Nervoso/metabolismo , Precursores de RNA/metabolismo , Spliceossomos/metabolismo , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Humanos , Mutação , Proteínas do Tecido Nervoso/genética , Ligação Proteica/genética , Estrutura Terciária de Proteína/fisiologia , Splicing de RNA/fisiologia , Fatores de Processamento de RNA , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Proteínas do Complexo SMN , Transcrição Gênica , XenopusRESUMO
Organic agriculture is increasingly of interest. The first organic farm in the Netherlands was established 70 years ago. Since then, the practice of this type of agriculture has grown. Although still relatively small scale, organic farming has a potential that is recognized in practice, in agricultural policies, and by the public.