50 research outputs found

    Microbial protein synthesis and nitrogen balance in crossbred heifers fed with two tannins sources

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    Tannins have been used to trigger positive effects on ruminal metabolism. So, increasing levels of tannic acid in a sorghum-based diet for five Holstein/Zebu crossbred lactating heifers were subject to a 5 × 5 Latin square experimental design, five heifers x five tannins acid levels x five periods. The excretion of total purine derivatives, through the collection of spot urine samples, and the N concentration values in the milk and urine were used. All heifers received 9.87 kg/DM of corn silage as roughage and 6.38 kg of concentrate (not fed ad libitum). Diet 1 (control) contained low-tannin sorghum (0.027kg total tannin), and the other diets contained high-tannin sorghum. The levels of tannic acid added used were established based on the quantity of condensed tannin in high-tannin sorghum. Thus, diets 2, 3, 4, and 5 were supplemented with 1.5g (13.%DM), 79.5g (2.6%DM), 157.5g (3.9%DM), and 235.5g (5.2%DM) of tannic acid totalling 0.078, 0.156, 0.234, and 0.321 total tannin kg/day respectively. The urinary excretions of urea (2.0055), total allantoin (185.12  mmol/day-1) , and total purine derivatives (222.32 mmol/day-1); absorbed purines 179.3 mmol/day-1); the N microbian synthesis (130.358 (g)N/day-1); and the concentrations of allantoin in milk (36.40 mmol/day-1) were not affected by the diets. Diets using two tannins sources supplementation did not affect the animal’s health, that is, it did not change the blood and metabolic rates above the normality indices for the animal category, neither improved the efficiency of the microbial synthesis nor the balance of N for milk productionLow to moderate concentrations of condensed tannins in ruminant diets are considered to increase the post-ruminal flow of non-ammonia nitrogen. The objective of this research was study the microbial protein synthesis and nitrogen balance of lactating cows fed with a diet of two tannin sources, based on sorghum (condensed tannin) with increasing levels of tannic acid (hydrolysable tannin). So, increasing levels of tannic acid in a sorghum-based diet for five Holstein/Zebu crossbred lactating heifers were subject to a 5 × 5 Latin square experimental design, five heifers x five tannins acid levels x five periods. The excretion of total purine derivatives, through the collection of spot urine samples, and the N concentration values in the milk and urine were used. All heifers received 9.87 kg/DM of corn silage as roughage and 6.38 kg of concentrate (not fed ad libitum). Diet 1 (control) contained low-tannin sorghum (0.027 kg total tannin), and the other diets contained high-tannin sorghum. The levels of tannic acid added used were established based on the quantity of condensed tannin in high-tannin sorghum. Thus, diets 2, 3, 4, and 5 were supplemented with 1.5g (13% DM), 79.5g (2.6% DM), 157.5 g (3.9% DM), and 235.5 g (5.2% DM) of tannic acid totalling 0.078, 0.156, 0.234, and 0.321 total tannin kg/day respectively. The urinary excretions of urea (2.0055), total allantoin (185.12 mmol/day-1), and total purine derivatives (222.32 mmol/day-1); absorbed purines 179.3 mmol/day-1); the N microbian synthesis (130.358 (g)N/day-1); and the concentrations of allantoin in milk (36.40 mmol/day-1) were not affected by the diets. Diets using two tannins (hydrolysable and condensed) sources supplementation didn’t affect the animals’ health, neither improved the microbial synthesis efficiency nor the N balance for milk production

    Global urban environmental change drives adaptation in white clover.

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Global urban environmental change drives adaptation in white clover

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Desenvolvimento de um submodelo bicompartimental para estimação da fração digestível da proteína bruta em bovinos a partir da composição química dos alimentos

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    Objetivou-se propor e validar um submodelo bicompartimental para estimação da fração protéica aparentemente digestível (PBad) em alimentos ofertados a bovinos em condições tropicais. Os dois compartimentos teóricos utilizados como base para o submodelo foram proteína bruta de conteúdo celular (PBCC) e proteína bruta de parede celular (PBPC). O teor de proteína insolúvel em detergente neutro (PIDN) foi utilizado como aproximação analítica para PBPC. A avaliação das frações digestíveis verdadeiras da PBCC e da PBPC se baseou no conceito de entidade nutricional e na disponibilidade potencial a partir da proteína indegradável insolúvel em detergente neutro (PIIDN), respectivamente. A estrutura básica do submodelo foi: PBad (% MS) = 0,98 × (PB - PIDN) + 0,835 × (PIDN - PIIDN) - 1,61 e PBad (% MS) = 0,98 × (PB - PIDN) + 0,67 × (PIDN - PIIDN) - 0,97 para bovinos em crescimento e terminação e vacas em lactação, respectivamente. A validação do submodelo foi realizada a partir dos resultados obtidos em dois ensaios com bovinos em crescimento e terminação envolvendo oito alimentos. O submodelo apresentou estimativas similares às obtidas in vivo. As estimativas de PBad foram também obtidas a partir de um submodelo unicompartimental previamente proposto. As estimativas produzidas pelo novo submodelo apresentaram maior exatidão e precisão em comparação às obtidas pelo submodelo unicompartimental
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