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1.
J Dairy Sci ; 107(2): 902-916, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37776997

RESUMO

The concept that fat supplementation impairs total-tract fiber digestibility in ruminants has been widely accepted over the past decades. Nevertheless, the recent interest in the dietary fatty acid profile to dairy cows enlightened the possible beneficial effect of specific fatty acids (e.g., palmitic, stearic, and oleic acids) on total-tract fiber digestibility. Because palmitic, stearic, and oleic acids are the main fatty acids present in ruminal bacterial cells, we hypothesize that the dietary supply of these fatty acids will favor their incorporation into the bacterial cell membranes, which will support the growth and enrichment of fiber-digesting bacteria in the rumen. Our objective in this experiment was to investigate how dietary supply of palmitic, stearic, and oleic acid affect fiber digestion, bacterial membrane fatty acid profile, microbial growth, and composition of the rumen bacterial community. Diets were randomly assigned to 8 single-flow continuous culture fermenters arranged in a replicated 4 × 4 Latin square with four 11-d experimental periods. Treatments were (1) a control basal diet without supplemental fatty acids (CON); (2) the control diet plus palmitic acid (PA); (3) the control diet plus stearic acid (SA); and (4) the control diet plus oleic acid (OA). All fatty acid treatments were included in the diet at 1.5% of the diet (dry matter [DM] basis). The basal diet contained 50% orchardgrass hay and 50% concentrate (DM basis) and was supplied at a rate of 60 g of DM/d in 2 equal daily offers (0800 and 1600 h). Data were analyzed using a mixed model considering treatments as fixed effect and period and fermenter as random effects. Our results indicate that PA increased in vitro fiber digestibility by 6 percentage units compared with the CON, while SA had no effect and OA decreased fiber digestibility by 8 percentage units. Oleic acid decreased protein expression of the enzymes acetyl-CoA carboxylase compared with CON and PA, while fatty acid synthase was reduced by PA, SA, and OA. We observed that PA, but not SA or OA, altered the bacterial community composition by enhancing bacterial groups responsible for fiber digestion. Although the dietary fatty acids did not affect the total lipid content and the phospholipid fraction in the bacterial cell, PA increased the flow of anteiso C13:0 and anteiso C15:0 in the phospholipidic membrane compared to the other treatments. In addition, OA increased the flow of C18:1 cis-9 and decreased C18:2 cis-9,cis-12 in the bacterial phospholipidic membranes compared to the other treatments. Palmitic acid tended to increase bacterial growth compared to other treatments, whereas SA and OA did not affect bacterial growth compared with CON. To our knowledge, this is the first research providing evidence that palmitic acid supports ruminal fiber digestion through shifts in bacterial fatty acid metabolism that result in changes in growth and abundance of fiber-degrading bacteria in the microbial community.


Assuntos
Suplementos Nutricionais , Ácido Oleico , Bovinos , Feminino , Animais , Ácido Oleico/metabolismo , Leite/metabolismo , Lactação , Rúmen/metabolismo , Digestão , Ácidos Graxos/metabolismo , Dieta/veterinária , Ácido Palmítico/metabolismo
2.
Science ; 382(6666): 103-109, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37797008

RESUMO

Indigenous societies are known to have occupied the Amazon basin for more than 12,000 years, but the scale of their influence on Amazonian forests remains uncertain. We report the discovery, using LIDAR (light detection and ranging) information from across the basin, of 24 previously undetected pre-Columbian earthworks beneath the forest canopy. Modeled distribution and abundance of large-scale archaeological sites across Amazonia suggest that between 10,272 and 23,648 sites remain to be discovered and that most will be found in the southwest. We also identified 53 domesticated tree species significantly associated with earthwork occurrence probability, likely suggesting past management practices. Closed-canopy forests across Amazonia are likely to contain thousands of undiscovered archaeological sites around which pre-Columbian societies actively modified forests, a discovery that opens opportunities for better understanding the magnitude of ancient human influence on Amazonia and its current state.


Assuntos
Arqueologia , Florestas , Humanos , Brasil
3.
Sci Rep ; 13(1): 11257, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438385

RESUMO

This paper presents two algorithms for the large-scale automatic detection and instance segmentation of potential archaeological mounds on historical maps. Historical maps present a unique source of information for the reconstruction of ancient landscapes. The last 100 years have seen unprecedented landscape modifications with the introduction and large-scale implementation of mechanised agriculture, channel-based irrigation schemes, and urban expansion to name but a few. Historical maps offer a window onto disappearing landscapes where many historical and archaeological elements that no longer exist today are depicted. The algorithms focus on the detection and shape extraction of mound features with high probability of being archaeological settlements, mounds being one of the most commonly documented archaeological features to be found in the Survey of India historical map series, although not necessarily recognised as such at the time of surveying. Mound features with high archaeological potential are most commonly depicted through hachures or contour-equivalent form-lines, therefore, an algorithm has been designed to detect each of those features. Our proposed approach addresses two of the most common issues in archaeological automated survey, the low-density of archaeological features to be detected, and the small amount of training data available. It has been applied to all types of maps available of the historic 1″ to 1-mile series, thus increasing the complexity of the detection. Moreover, the inclusion of synthetic data, along with a Curriculum Learning strategy, has allowed the algorithm to better understand what the mound features look like. Likewise, a series of filters based on topographic setting, form, and size have been applied to improve the accuracy of the models. The resulting algorithms have a recall value of 52.61% and a precision of 82.31% for the hachure mounds, and a recall value of 70.80% and a precision of 70.29% for the form-line mounds, which allowed the detection of nearly 6000 mound features over an area of 470,500 km2, the largest such approach to have ever been applied. If we restrict our focus to the maps most similar to those used in the algorithm training, we reach recall values greater than 60% and precision values greater than 90%. This approach has shown the potential to implement an adaptive algorithm that allows, after a small amount of retraining with data detected from a new map, a better general mound feature detection in the same map.

4.
PLoS One ; 18(6): e0272226, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37319229

RESUMO

Tupí-Guaraní is one of the largest branches of the Tupían language family, but despite its relevance there is no consensus about its origins in terms of age, homeland, and expansion. Linguistic classifications vary significantly, with archaeological studies suggesting incompatible date ranges while ethnographic literature confirms the close similarities as a result of continuous inter-family contact. To investigate this issue, we use a linguistic database of cognate data, employing Bayesian phylogenetic methods to infer a dated tree and to build a phylogeographic expansion model. Results suggest that the branch originated around 2500 BP in the area of the upper course of the Tapajós-Xingu basins, with a split between Southern and Northern varieties beginning around 1750 BP. We analyse the difficulties in reconciling archaeological and linguistic data for this group, stressing the importance of developing an interdisciplinary unified model that incorporates evidence from both disciplines.


Assuntos
Arqueologia , Idioma , Filogenia , Teorema de Bayes , Linguística
5.
PLoS One ; 17(7): e0268482, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35816489

RESUMO

The emergence of Neolithic economies and their spread through Eurasia was one of the most crucial transitions of the Holocene, with different mechanisms of diffusion-demic, cultural-being proposed. While this phenomenon has been exhaustively studied in Europe, with repeated attempts to model the speed of Neolithic diffusion based on radiocarbon dates, much less attention has been devoted to the dispersal towards the East, and in particular to South Asia. The Neolithic in the latter region at least partly derived from southwest Asia, given the presence of "founder crops" such as wheat and barley. The process of their eastward diffusion, however, may have been significantly different to the westward dispersal, which was mainly due to demic diffusion, as local domesticates were already available and farming was already practiced in parts of South Asia. Here, we use radiocarbon dates specifically related to the spread of the southwest Asian Neolithic crops to model the speed of dispersal of this agricultural package towards South Asia. To assess potential geographical and environmental effects on the dispersal, we simulate different speeds depending on the biomes being crossed, employing a genetic algorithm to search for the values that most closely approach the radiocarbon dates. We find that the most important barrier to be crossed were the Zagros mountains, where the speed was lowest, possibly due to topography and climate. A large portion of the study area is dominated by deserts and shrublands, where the speed of advance, albeit closer to the range expected for demic diffusion, was lower than observed in Europe, which can also potentially be attributed to environmental constraints in the adaptation of the crops. Finally, a notable acceleration begins in the Indus valley, exceeding the range of demic diffusion in the tropical and subtropical environments east of the Indus. We propose that the latter is due to the rapid diffusion among populations already familiar with plant cultivation.


Assuntos
Agricultura , Embalagem de Medicamentos , Europa (Continente) , Geografia , Oriente Médio
6.
Philos Trans R Soc Lond B Biol Sci ; 377(1849): 20200499, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35249381

RESUMO

The southwestern Amazon Rainforest Ecotone (ARE) is the transitional landscape between the tropical forest and seasonally flooded savannahs of the Bolivian Llanos de Moxos. These heterogeneous landscapes harbour high levels of biodiversity and some of the earliest records of human occupation and plant domestication in Amazonia. While persistent Indigenous legacies have been demonstrated elsewhere in the Amazon, it is unclear how past human-environment interactions may have shaped vegetation composition and structure in the ARE. Here, we examine 6000 years of archaeological and palaeoecological data from Laguna Versalles (LV), Bolivia. LV was dominated by stable rainforest vegetation throughout the Holocene. Maize cultivation and cultural burning are present after ca 5700 cal yr BP. Polyculture cultivation of maize, manioc and leren after ca 3400 cal yr BP predates the formation of Amazonian Dark/Brown Earth (ADE/ABE) soils (approx. 2400 cal yr BP). ADE/ABE formation is associated with agroforestry indicated by increased edible palms, including Mauritia flexuosa and Attalea sp., and record levels of burning, suggesting that fire played an important role in agroforestry practices. The frequent use of fire altered ADE/ABD forest composition and structure by controlling ignitions, decreasing fuel loads and increasing the abundance of plants preferred by humans. Cultural burning and polyculture agroforestry provided a stable subsistence strategy that persisted despite pronounced climate change and cultural transformations and has an enduring legacy in ADE/ABE forests in the ARE. This article is part of the theme issue 'Tropical forests in the deep human past'.


Assuntos
Florestas , Floresta Úmida , Biodiversidade , Bolívia , Mudança Climática , Humanos , Plantas , Árvores
7.
J R Soc Interface ; 18(183): 20210499, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34610263

RESUMO

The expansion of forest farmers across tropical lowland South America during the Late Holocene has long been connected to climate change. The more humid conditions established during the Late Holocene are assumed to have driven the expansion of forests, which would have facilitated the dispersal of cultures that practised agroforestry. The Tupi, a language family of widespread distribution in South America, occupies a central place in the debate. Not only are they one of the largest families in the continent, but their expansion from an Amazonian homeland has long been hypothesized to have followed forested environments wherever they settled. Here, we assess that hypothesis using a simulation approach. We employ equation-based and cellular automaton models, simulating demic-diffusion processes under two different scenarios: a null model in which all land cells can be equally settled, and an alternative model in which non-forested cells cannot be settled or delay the expansion. We show that including land cover as a constraint to movement results in a better approximation of the Tupi expansion as reconstructed by archaeology and linguistics.


Assuntos
Arqueologia , Mudança Climática , Florestas , Linguística , América do Sul
8.
Oral Oncol ; 114: 105171, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33513474

RESUMO

OBJECTIVES: We report the results of this phase I study to evaluate the maximum tolerated dose (MTD) and safety of veliparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, combined with carboplatin and paclitaxel induction chemotherapy (IC) for locoregionally advanced head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: In a 3 + 3 cohort design, patients with stage IVA-B human papillomavirus-negative HNSCC received 2 cycles of carboplatin (AUC 6, day 1), paclitaxel (100 mg/m2, days 1, 8, 15) and veliparib (days 1-7) every 21 days followed by standard curative-intent chemoradiotherapy. Primary endpoint: MTD and recommended phase II dose (RP2D) as determined by the first IC cycle. RESULTS: Twenty patients enrolled. Two withdrew before treatment; 18 patients were analyzed. Median age was 63 years. Primary disease sites included hypopharynx (n = 5), larynx (n = 5), oral cavity (n = 4), oropharynx (n = 3), and nasal cavity (n = 1). Through all of IC, the most common grade 3 + adverse events (AEs) were neutropenia (33%), thrombocytopenia (33%), anemia (11%), and white blood cell decrease (11%). One patient experienced a hematologic DLT at 350 mg BID. The RP2D for veliparib combined with carboplatin/paclitaxel is 350 mg BID. With 40.9 month median follow-up across dose levels for all patients, the 24-month overall and progression free survival was 77.8% (95% CI 60.8-99.6%) and 66.7% (95% CI 48.1-92.4%), respectively. Medians have not been reached. CONCLUSION: Addition of veliparib to carboplatin and paclitaxel IC was well tolerated in patients with advanced HNSCC. Hematologic toxicities were the most common AEs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzimidazóis/uso terapêutico , Carboplatina/uso terapêutico , Paclitaxel/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzimidazóis/farmacologia , Carboplatina/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Adulto Jovem
9.
J Dairy Sci ; 103(12): 11472-11482, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33069410

RESUMO

We evaluated the effects of altering the dietary ratio of palmitic (C16:0; PA) and oleic (cis-9 C18:1; OA) acids on production responses of cows with a wide range of milk production (32 to 65 kg/d) in a crossover design experiment with a preliminary period. Thirty-two multiparous Holstein cows (144 ± 54 d in milk) were assigned randomly to a treatment sequence. Treatments were diets supplemented with fatty acid (FA) blends (1.5% of diet dry matter) that provided 80% C16:0 + 10% cis-9 C18:1 (PA) and 60% C16:0 + 30% cis-9 C18:1 (PA+OA). The corn silage and alfalfa-based diets contained 20.0% forage neutral detergent fiber (NDF), 28.5% starch, and 17.1% crude protein. Treatment periods were 21 d with the final 5 d used for data and sample collection. Treatment did not affect dry matter intake (DMI), milk yield, energy-corrected milk (ECM), body weight, or body weight change. The PA+OA diet increased total, 16-carbon, and 18-carbon FA digestibility compared with the PA diet. Compared with PA+OA, PA increased fat yield (1.97 vs. 1.91 kg/d) and protein yield (1.61 vs. 1.55 kg/d). The PA diet also increased the yield of de novo (448 vs. 428 g/d) and mixed (749 vs. 669 g/d) milk FA and decreased the yield of preformed FA (605 vs. 627 g/d) compared with PA+OA. Interactions were detected between treatment and preliminary milk yield for DMI, total FA intake, 16-carbon FA intake, ECM, 3.5% fat-corrected milk (linear interaction), and a tendency for milk yield (linear interaction); lower-producing cows (<45 kg/d) had increased DMI and ECM on the PA diet, whereas higher-producing cows (>55 kg/d) had increased DMI and ECM on the PA+OA diet. A linear interaction was detected between treatment and preliminary milk yield for mixed milk FA yield (linear interaction) and a tendency for de novo milk FA yield (linear interaction). Our results demonstrate that feeding a fat supplement containing more cis-9 C18:1 replacing C16:0 increased production responses (DMI, milk yield, and ECM) in higher-producing cows, but decreased production responses in lower-producing cows.


Assuntos
Bovinos/fisiologia , Dieta/veterinária , Lactação/fisiologia , Ácidos Oleicos/administração & dosagem , Ácido Palmítico/administração & dosagem , Ração Animal/análise , Animais , Peso Corporal , Fibras na Dieta/administração & dosagem , Suplementos Nutricionais , Ingestão de Alimentos , Ácidos Graxos/administração & dosagem , Feminino , Medicago sativa , Leite/metabolismo , Silagem , Zea mays
10.
Cancer J ; 26(4): 311-322, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32732674

RESUMO

Value-based care within insurance design utilizes evidence-based medicine as a means of defining high-value versus low-value diagnostics and treatments. The goals of value-based care are to shift spending and coverage toward high-value care and reduce the use of low-value practices. Within oncology, several value-based methods have been proposed and implemented. We review value-based care being used within oncology, including defining the value of oncology drugs through frameworks, clinical care pathways, alternative payment models including the Oncology Care Model, value-based insurance design, and reducing low-value care including the Choosing Wisely initiatives.


Assuntos
Gastos em Saúde/normas , Oncologia/organização & administração , Humanos
11.
J Dairy Sci ; 103(10): 8898-8909, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32713701

RESUMO

This study evaluated the effect of feeding a palmitic acid-enriched supplement on production responses and nitrogen metabolism of mid-lactating Holstein and Jersey cows. Eighty mid-lactating dairy cows, 40 Holstein and 40 Jersey, were used in a randomized complete block design with a split-plot arrangement; the main plot was breed and the subplot was fatty acid treatment. Cows within each breed were assigned to 1 of 2 treatments: (1) control diet with no fat supplement or (2) control diet plus a palmitic acid-enriched supplement dosed at 1.5% of diet dry matter (PA treatment). The treatment period was 6 wk with the final 3 wk used for data and sample collection. There were no treatment × breed interactions for the variables analyzed. Compared with control, PA treatment increased milk fat yield (1.36 vs. 1.26 kg/d) and tended to increase 3.5% fat-corrected milk (35.6 vs. 34.0 kg/d) and energy-corrected milk (35.7 vs. 34.1 kg/d). There was no effect of PA treatment on dry matter intake, milk yield, milk protein yield, milk lactose yield, body condition score, body weight (BW) change, nitrogen intake, and variables related to nitrogen metabolism and excretion. Compared with Holstein cows, Jersey cows had greater dry matter intake as a percent of BW (4.90 vs. 3.37% of BW) and lower milk production (29.6 vs. 32.7 kg/d) and milk lactose yield (1.58 vs. 1.42 kg/d), but tended to have greater milk fat yield (1.36 vs. 1.26 kg/d). There was a breed effect on BW change; Holstein cows gained 0.385 kg/d during the experiment, and Jersey cows gained 0.145 kg/d. Jersey cows had lower nitrogen intake (636 vs. 694 g/d), blood urea nitrogen (12.6 vs. 13.8 mg/dL), urine total nitrogen (125 vs. 145 g/d), and urine total nitrogen as a percent of nitrogen intake (19.5 vs. 21.1%). Overall, feeding a palmitic acid-enriched supplement increased milk fat yield as well as dry matter and fiber digestibility in both Holstein and Jersey cows. The PA treatment did not have any major effects on nitrogen metabolism in both Holstein and Jersey cows. In addition, our results indicated that Jersey cows had lower urinary nitrogen excretion (g/d) than Holstein cows.


Assuntos
Bovinos/metabolismo , Lactação/efeitos dos fármacos , Nitrogênio/metabolismo , Ácido Palmítico/administração & dosagem , Ração Animal/análise , Animais , Dieta/veterinária , Fibras na Dieta/administração & dosagem , Suplementos Nutricionais , Digestão/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Lactação/fisiologia , Lactose/análise , Leite/química , Leite/efeitos dos fármacos , Nitrogênio/urina , Especificidade da Espécie
12.
PLoS One ; 15(4): e0232367, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32339209

RESUMO

Human expansions motivated by the spread of farming are one of the most important processes that shaped cultural geographies during the Holocene. The best known example of this phenomenon is the Neolithic expansion in Europe, but parallels in other parts of the globe have recently come into focus. Here, we examine the expansion of four archaeological cultures of widespread distribution in lowland South America, most of which originated in or around the Amazon basin and spread during the late Holocene with the practice of tropical forest agriculture. We analyze spatial gradients in radiocarbon dates of each culture through space-time regressions, allowing us to establish the most likely geographical origin, time and speed of expansion. To further assess the feasibility of demic diffusion as the process behind the archaeological expansions in question, we employ agent-based simulations with demographic parameters derived from the ethnography of tropical forest farmers. We find that, while some expansions can be realistically modeled as demographic processes, others are not easily explainable in the same manner, which is possibly due to different processes driving their dispersal (e.g. cultural diffusion) or problematic/incomplete archaeological data.


Assuntos
Evolução Cultural/história , Migração Humana/história , Modelos Teóricos , Análise Espaço-Temporal , Agricultura , Arqueologia , Simulação por Computador , História Antiga , Humanos , Idioma , América do Sul
13.
J Dairy Sci ; 103(6): 5131-5142, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253043

RESUMO

We evaluated the effects of commercially available fatty acid (FA) supplements containing palmitic (C16:0) and stearic acid (C18:0) on nutrient digestibility and production responses of dairy cows. Thirty-six mid-lactation (146 ± 55 d in milk) multiparous Holstein cows were randomly assigned to twelve 3 × 3 balanced truncated Latin squares, with 3 treatments and 2 consecutive 35-d periods, with the final 5 d used for sample and data collection. Treatments were (1) a control diet containing no supplemental FA (CON), (2) a control diet supplemented with a commercially available C16:0 supplement (PA), and (3) a control diet supplemented with a commercially available C16:0 and C18:0 supplement (MIX). Supplements were fed at 1.5% dry matter and replaced soyhulls in CON. The statistical model included the random effect of cow nested within square and the fixed effects of treatment, period, square, and their interactions. Preplanned contrasts were (1) overall effect of FA treatments [CON vs. the average of the FA treatments (FAT); 1/2 (PA + MIX)], and (2) effect of FA supplement (PA vs. MIX). Treatment had no effects on dry matter intake, body weight, or body weight change. Compared with CON, FAT decreased digestibilities of total FA and 18-carbon FA but did not affect dry matter and neutral detergent fiber digestibility. Compared with MIX, PA increased dry matter and neutral detergent fiber digestibilities by 3.6 and 4.8 percentage units, respectively. The PA also increased total FA and 18-carbon FA digestibilities but did not alter 16-carbon FA digestibility compared with MIX. Using a Lucas test, we estimated apparent digestibility coefficients of 0.768 and 0.553 for the PA and MIX supplements, respectively. Compared with CON, FAT increased milk yield and tended to increase energy-corrected milk, but did not affect yield of milk fat or milk protein. The PA increased energy-corrected milk and milk fat yield but had no effect on milk protein yield compared with MIX. Our results indicate that dairy cows producing around 45 kg of milk respond better to a FA supplement enriched in C16:0 compared with a supplement containing both C16:0 and C18:0, which is likely due in part to PA increasing FA and neutral detergent fiber digestibility compared with MIX.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais/análise , Lactação/efeitos dos fármacos , Leite/metabolismo , Ácido Palmítico/farmacologia , Ácidos Esteáricos/farmacologia , Ração Animal/análise , Animais , Peso Corporal/efeitos dos fármacos , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão/efeitos dos fármacos , Feminino , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Gotículas Lipídicas , Leite/química , Proteínas do Leite/metabolismo , Nutrientes/metabolismo , Distribuição Aleatória
14.
J Dairy Sci ; 103(2): 1944-1955, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759597

RESUMO

Oxidized linoleic acid metabolites (OXLAM) are products of adipocyte lipolysis with the potential to modulate adipose tissue (AT) lipid metabolism and inflammation. In periparturient cows, linoleic acid is preferentially mobilized from AT during lipolysis by hormone-sensitive lipase (HSL) compared with other polyunsaturated fatty acids. Enzymatic and nonenzymatic reactions generate OXLAM from linoleic acid. Among OXLAM, 9-, 10-, and 12-hydroxy-octadecadienoic acids (HODE) are associated with pro-inflammatory responses, whereas 9- and 13-oxo-octadecadienoic acids (oxoODE) and 13-HODE can facilitate inflammation resolution and promote lipogenesis. This study evaluated the effect of HSL activity on OXLAM biosynthesis using subcutaneous AT explants collected from multiparous dairy cows at 10 d before and again at 10 and 24 d after calving. Explants were treated for 3 h without or with the ß-adrenergic agonist isoproterenol (ISO; 1 µM; MilliporeSigma, Burlington, MA) to induce HSL activity. The contribution of HSL to OXLAM biosynthesis was determined by inhibiting its activity with CAY10499 (2 µM; Cayman Chemical, Ann Arbor, MI). After treatments, media and explants were collected for lipidomic analysis using HPLC-tandem mass spectroscopy. Results indicated that ISO increased the biosynthesis of 9-, 12-, and 13-HODE and 9-oxoODE, and this effect was reduced at 24 d after calving. Inhibiting HSL activity partially reversed ISO effects on HODE and 9-oxoODE. Our ex vivo model demonstrated for the first time a direct effect of HSL activity on the biosynthesis of OXLAM in AT, especially at 10 d before and 10 d after calving. The biosynthesis of anti-inflammatory OXLAM is limited during the first weeks after parturition and may promote AT inflammation and lipolytic responses to negative energy balance. These results indicate that HSL activity releases linoleic acid for OXLAM biosynthesis in concentrations of a magnitude that may bypass the need for the activation of phospholipases linked with the inflammatory cascade and thus supports, in part, lipolysis-driven inflammation within AT of periparturient cows.


Assuntos
Anti-Inflamatórios/metabolismo , Bovinos/fisiologia , Ácido Linoleico/metabolismo , Ácidos Linoleicos/metabolismo , Lipólise , Esterol Esterase/metabolismo , Adipócitos/metabolismo , Animais , Metabolismo Energético , Feminino , Inflamação/veterinária , Isoprostanos/metabolismo , Lactação , Lipogênese/efeitos dos fármacos , Oxirredução , Parto , Gravidez , Gordura Subcutânea/metabolismo
15.
J Anim Sci ; 97(8): 3562-3577, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31181141

RESUMO

Flint corn processing method [coarse ground corn (CGC; 3.2 mm average particle size) or steam-flaked corn (SFC; 0.360 kg/L flake density)] was evaluated in conjunction with 4 levels of NDF from sugarcane bagasse (SCB) as roughage source (RNDF; 4%, 7%, 10%, and 13%; DM basis) to determine impact on growth performance, carcass characteristics, starch utilization, feeding behavior, and rumen morphometrics of Bos indicus beef cattle. Two hundred and forty Nellore bulls were blocked by initial BW (350 ± 37 kg), assigned to 32 feedlot pens and pens within weight block were randomly assigned, in a 2 × 4 factorial arrangement (2 corn processing and 4 levels of RNDF) to treatments. Effects of corn grain processing × RNDF level were not detected (P ≥ 0.14) for growth performance, dietary net energy concentration, carcass traits, rumen morphometrics, and feeding behavior, except for time spent ruminating and time spent resting (P ≤ 0.04), and a tendency for papillae width (P ≤ 0.09). Bulls fed SFC-based diets consumed 7% less (P = 0.001), had 10.6% greater carcass-adjusted ADG (P < 0.001) and 19% greater carcass-adjusted feed efficiency (P < 0.001) compared with bulls fed CGC-based diets. Observed net energy for maintenance and gain values were 14.9% and 19.4% greater (P < 0.001), respectively, for SFC than for CGC-based diets. Fecal starch concentration was less (P < 0.001) for bulls fed SFC compared with those fed CGC. No grain processing effects were detected (P = 0.51) for rumenitis score; however, cattle fed SFC presented smaller ruminal absorptive surface area (P = 0.03). Dry matter intake increased linearly (P = 0.02) and carcass-adjusted feed efficiency tended (P = 0.06) to decrease linearly as RNDF increased. Dietary RNDF concentration did not affect carcass characteristics (P ≥ 0.19), except for dressing percentage, which tended to decrease linearly (P = 0.06) as RNDF in finishing diets increased. Increasing RNDF in finishing diets had no effect (P = 0.26) on time spent eating, but time spent ruminating and resting increased linearly (min/d; P < 0.001) with increased dietary RNDF. Steam flaking markedly increased flint corn energy value, net energy of diets, and animal growth performance, and led to improvements on feed efficiency when compared with grinding, regardless of RNDF content of diets. Increasing dietary RNDF compromised feedlot cattle feed efficiency and carcass dressing.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Celulose/farmacologia , Fibras na Dieta/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Metabolismo Energético/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Masculino , Minerais/farmacologia , Carne Vermelha/análise , Rúmen/anatomia & histologia , Rúmen/efeitos dos fármacos , Amido/metabolismo , Zea mays
16.
Nat Ecol Evol ; 3(7): 1007-1017, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209292

RESUMO

The long-term response of ancient societies to climate change has been a matter of global debate. Until recently, the lack of integrative studies using archaeological, palaeoecological and palaeoclimatological data prevented an evaluation of the relationship between climate change, distinct subsistence strategies and cultural transformations across the largest rainforest of the world, Amazonia. Here we review the most relevant cultural changes seen in the archaeological record of six different regions within Greater Amazonia during late pre-Columbian times. We compare the chronology of those cultural transitions with high-resolution regional palaeoclimate proxies, showing that, while some societies faced major reorganization during periods of climate change, others were unaffected and even flourished. We propose that societies with intensive, specialized land-use systems were vulnerable to transient climate change. In contrast, land-use systems that relied primarily on polyculture agroforestry, resulting in the formation of enriched forests and fertile Amazonian dark earth in the long term, were more resilient to climate change.


Assuntos
Mudança Climática , Florestas , Arqueologia , Brasil , Floresta Úmida
17.
Theriogenology ; 127: 145-152, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30695743

RESUMO

Reproductive diseases affect 25% of dairy cows in the US and often develop from retention of the placenta. It is well established that expulsion of the placenta is a highly regulated inflammatory process, but the mechanisms by which dysregulation of uterine immune responses impair this process are poorly understood. In healthy non-ruminants, pro-inflammatory M1 macrophages are predominant in uterine tissue after parturition. However, macrophage phenotype in the postpartum bovine uterus is unknown. Our study compared macrophage phenotypes in the uterine caruncles of multiparous dairy cows that during the first day postpartum either retained (RET, n = 5) or had normal expulsion (NOR, n = 5) of placenta. Immune cells were sorted magnetically from the caruncular endometrial cell fraction using the CD172a marker and monocyte/macrophage population was characterized using flow cytometry. Transcriptional and protein expression studies were performed on uterine caruncles. Compared to NOR, RET samples showed a lower CD14+/CD16+ expression (P < 0.05) in caruncle monocyte/macrophage population. As opposed to NOR, RET further demonstrated greater expression of anti-inflammatory M2 macrophage associated genes CD206, C-type lectin domain family 7 member A (CLEC7A), and RNASE6. In addition, caruncles from RET showed decreased signal transducer and activator of transcription 3 (STAT3) activation, an important promoter of proteolytic activity, compared to NOR. Our studies demonstrate that there is an overall lower number of macrophage populations in the caruncle of cows with RET placenta and these are polarized towards M2 phenotype. Excessive accumulation of M2 macrophages may lead to reduced trafficking of immune cells into the caruncle thus impairing the inflammatory, phagocytic and proteolytic processes that lead to placental expulsion.


Assuntos
Doenças dos Bovinos/imunologia , Macrófagos/patologia , Placenta Retida/veterinária , Útero/patologia , Animais , Bovinos , Feminino , Citometria de Fluxo/veterinária , Fenótipo , Placenta Retida/imunologia , Gravidez
18.
Sci Rep ; 9(1): 20306, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31889126

RESUMO

The South American Monsoon System is responsible for the majority of precipitation in the continent, especially over the Amazon and the tropical savannah, known as 'Cerrado'. Compared to the extensively studied subtropical and temperate regions the effect of the Medieval Climate Anomaly (MCA) on the precipitation over the tropics is still poorly understood. Here, we present a multiproxy paleoprecipitation reconstruction showing a consistent change in the hydrologic regime during the MCA in the eastern Amazon and 'Cerrado', characterized by a substantial transition from humid to drier conditions during the Early (925-1150 C.E.) to Late-MCA (1150-1350 C.E.). We compare the timing of major changes in the monsoon precipitation with the expansion and abandonment of settlements reported in the archeological record. Our results show that important cultural successions in the pre-Columbian Central Amazon, the transition from Paredão to Guarita phase, are in agreement with major changes in the hydrologic regime. Phases of expansion and, subsequent abandonment, of large settlements from Paredão during the Early to Late-MCA are coherent with a reduction in water supply. In this context we argue that the sustained drier conditions during the latter period may have triggered territorial disputes with Guarita leading to the Paredão demise.

19.
Science ; 362(6420): 1309-1313, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30545889

RESUMO

Domesticated maize evolved from wild teosinte under human influences in Mexico beginning around 9000 years before the present (yr B.P.), traversed Central America by ~7500 yr B.P., and spread into South America by ~6500 yr B.P. Landrace and archaeological maize genomes from South America suggest that the ancestral population to South American maize was brought out of the domestication center in Mexico and became isolated from the wild teosinte gene pool before traits of domesticated maize were fixed. Deeply structured lineages then evolved within South America out of this partially domesticated progenitor population. Genomic, linguistic, archaeological, and paleoecological data suggest that the southwestern Amazon was a secondary improvement center for partially domesticated maize. Multiple waves of human-mediated dispersal are responsible for the diversity and biogeography of modern South American maize.


Assuntos
Evolução Biológica , Domesticação , Zea mays/classificação , Zea mays/genética , Genoma de Planta , Modelos Biológicos , Mutação , Filogenia , América do Sul
20.
Sci Rep ; 8(1): 13378, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30190510

RESUMO

Hormone sensitive lipase (HSL) activation is part of the metabolic adaptations to the negative energy balance common to the mammalian periparturient period. This study determined HSL contribution to adipose tissue (AT) lipolysis and how insulin regulates its activity in periparturient dairy cows. Subcutaneous AT (SCAT) samples were collected at 11 d prepartum (dry) and 11 (fresh) and 24 d (lactation) postpartum. Basal and stimulated lipolysis (ISO) responses were determined using explant cultures. HSL contribution to lipolysis was assessed using an HSL inhibitor (CAY). Basal lipolysis was higher in SCAT at dry compared with fresh. CAY inhibited basal lipolysis negligibly at dry, but at fresh and lactation it reduced basal lipolysis by 36.1 ± 4.51% and 43.1 ± 4.83%, respectively. Insulin inhibited lipolysis more pronouncedly in dry compared to fresh. Results demonstrate that HSL contribution to basal lipolysis is negligible prepartum. However, HSL is a major driver of SCAT lipolytic responses postpartum. Lower basal lipolysis postpartum suggests that reduced lipogenesis is an important contributor to fatty acid release from SCAT. Loss of adipocyte sensitivity to the antilipolytic action of insulin develops in the early lactation period and supports a state of insulin resistance in AT of cows during the first month postpartum.


Assuntos
Insulina/metabolismo , Lactação/fisiologia , Lipólise/fisiologia , Período Pós-Parto/fisiologia , Esterol Esterase/metabolismo , Gordura Subcutânea/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Bovinos , Feminino , Gordura Subcutânea/citologia
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