Mechanisms Underlying Gas Exchange Alterations In An Experimental Model Of Pulmonary Embolism.

The aim of the present study was to determine the ventilation/perfusion ratio that contributes to hypoxemia in pulmonary embolism by analyzing blood gases and volumetric capnography in a model of experimental acute pulmonary embolism. Pulmonary embolization with autologous blood clots was induced in seven pigs weighing 24.00 +/- 0.6 kg, anesthetized and mechanically ventilated. Significant changes occurred from baseline to 20 min after embolization, such as reduction in oxygen partial pressures in arterial blood (from 87.71 +/- 8.64 to 39.14 +/- 6.77 mmHg) and alveolar air (from 92.97 +/- 2.14 to 63.91 +/- 8.27 mmHg). The effective alveolar ventilation exhibited a significant reduction (from 199.62 +/- 42.01 to 84.34 +/- 44.13) consistent with the fall in alveolar gas volume that effectively participated in gas exchange. The relation between the alveolar ventilation that effectively participated in gas exchange and cardiac output (V Aeff/Q ratio) also presented a significant reduction after embolization (from 0.96 +/- 0.34 to 0.33 +/- 0.17 fraction). The carbon dioxide partial pressure increased significantly in arterial blood (from 37.51 +/- 1.71 to 60.76 +/- 6.62 mmHg), but decreased significantly in exhaled air at the end of the respiratory cycle (from 35.57 +/- 1.22 to 23.15 +/- 8.24 mmHg). Exhaled air at the end of the respiratory cycle returned to baseline values 40 min after embolism. The arterial to alveolar carbon dioxide gradient increased significantly (from 1.94 +/- 1.36 to 37.61 +/- 12.79 mmHg), as also did the calculated alveolar (from 56.38 +/- 22.47 to 178.09 +/- 37.46 mL) and physiological (from 0.37 +/- 0.05 to 0.75 +/- 0.10 fraction) dead spaces. Based on our data, we conclude that the severe arterial hypoxemia observed in this experimental model may be attributed to the reduction of the V Aeff/Q ratio. We were also able to demonstrate that V Aeff/Q progressively improves after embolization, a fact attributed to the alveolar ventilation redistribution induced by hypocapnic bronchoconstriction.391197-20

Bioprospection of Petit Verdot grape pomace as a source of anti-inflammatory compounds

The aim of this study was to evaluate the anti-inflammatory activity of Petit Verdot Extract and hexane, chloroform and ethyl acetate fractions obtained from grape pomace, in addition to identifying active compounds. The PVE and EAF reduced significantly paw edema and neutrophil migration when compared with control groups. The PVE reduced levels of TNF-α and IL1-β in the peritoneal fluid, whereas the EAF did not reduce cytokines significantly. Two hydroxybenzoic acids, two proanthocyanidins, three flavan-3-ol monomers and three anthocyanins were identified in the PVE and EAF by LC-MS/MS. The stilbene transresveratrol was identified only in the EAF. The phenolic compounds were quantified using HPLC-DAD analysis, except for the stilbenes, which were not sensible for the detection by the method. Since PVE and EAF showed significantly anti-inflammatory effects and high concentration of phenolic compounds, we concluded that Petit Verdot pomace could be an interesting source of anti-inflammatory bioactives

Bioprospection of Petit Verdot grape pomace as a source of anti-inflammatory compounds.

The aim of this study was to evaluate the anti-inflammatory activity of Petit Verdot Extract and hexane, chloroform and ethyl acetate fractions obtained from grape pomace, in addition to identifying active compounds. The PVE and EAF reduced significantly paw edema and neutrophil migration when compared with control groups. The PVE reduced levels of TNF-α and IL1-β in the peritoneal fluid, whereas the EAF did not reduce cytokines significantly. Two hydroxybenzoic acids, two proanthocyanidins, three flavan-3-ol monomers and three anthocyanins were identified in the PVE and EAF by LC-MS/MS. The stilbene transresveratrol was identified only in the EAF. The phenolic compounds were quantified using HPLC-DAD analysis, except for the stilbenes, which were not sensible for the detection by the method. Since PVE and EAF showed significantly anti-inflammatory effects and high concentration of phenolic compounds, we concluded that Petit Verdot pomace could be an interesting source of anti-inflammatory bioactives

Growth efficiency of Nellore cattle in the growing and finishing phases.

The objective of this work was to evaluate the growth efficiency of Nellore young bulls in the growing and fattening phases using the Kleiber index (KI). The experiment was carried out in the ABCZ experimental farm Orestes Prata Tibery Júnior, located at the MG-427 highway, Uberaba, MG, Brazil (lat. 19º 47´ 68´´ S; long. 47º 58' 50'' W, 788 m asl). The local climate is tropical semi-humid presenting mean air temperature of 21.4°C, annual rainfall of 1,684 mm and relative humidity of 71.4%. Young bulls (n = 101) were submitted to 280 days of evaluation under grazing in Brachiaria brizantha cv. BRS Paiaguás pastures, 140 days during the wet season and 140 days during the dry season, measuring the weight of the animals and the average daily live weight gain (ADG). After this period, in the feedlot, the same animals were maintained in pens with automated troughs for 109 days to measure live weight and individual intake. It was estimated the feed efficiency (FE), the residual feed intake (RFI), the feed intake (FI), the dry matter intake (DMI) and the KI, dividing the average daily gain (ADG) by the average metabolic live weight (AMLW). Data were analyzed with Pearson's correlation at P < 0.05 using the software Action. Correlated data were observed for Kleiber index (KI) and FI (0.62), and for KI and ADG (0.86). The correlation between KI and gross FE was significant (P < 0.01) and of strong magnitude, with a value of 0.79. The KI did not correlated with RFI (0.012), but correlated negatively with FI (-0.80). There was no correlation between ADG, AMLW and KI, when the values obtained from cattle maintained at different phases were analyzed. Kleiber index can be used as a tool for animal selection in the feedlot, as it has high correlation with ADG and FE. However, studies on the Kleiber Index are still needed to validate this hypothesis, especially with regard to the selection of animals based only on the efficiency presented in confinement and how it will reflect on animals kept under the grazing system that is the most used in this country

Feed efficiency of dairy Gir heifers in the feedlot.

The objective of the study was to evaluate the feed efficiency of Gir heifers in the feedlot through the residual feed intake (RFI) evaluation. The experiment was carried out on the campus of Faculdades Associadas in Uberaba, MG, Brazil. It was evaluated 43 dairy Gir heifers from the Genetic Breeding Program of EPAMIG, with initial age and mean live weight of 20 months and 279 kg, respectively (Ethics Committee approval of Epamig: 02/2020). Heifers were housed in a feedlot containing electronic troughs and weighing scales. The experimental period lasted 91 days with 21 of adaptation and 70 days of evaluation, from 12/26/2020 to 03/27/2021. The diet was formulated to provide 0.450 kg LW/head/day and had a forage:concentrate ratio of 74:26, with 76.4% of corn silage and 23.6% of concentrate, containing 8.3% of crude protein (CP) and 64.8% of total digestible nutrients (TDN) on dry matter (DM) basis. The RFI was determined and then two experimental heifer groups were formed, a positive RFI and a negative RFI. They were compared in terms of average daily gain (ADG), feed conversion (FC), daily dry matter intake (DMI), and gross feed efficiency (GFE). The experimental design was completely randomized and means were compared using Tukey test at 5% of significance. In the evaluation of heifers, 24 had negative RFI and 19 positive RFI. About 56% of the heifers had lower DMI compared to estimated, of which considered more efficient. There was a difference (P0.05) for ADG (0.45 and 0.44 kg LW/head/day), FC (15.4 and 13.2 kg DM/kg ADG), GFE (0.07 and 0.08 kg ADG/kg DMI), respectively for negative and positive RFI. Consequently, negative RFI heifers consume less with the same live weight gain, allowing better-feed conversion in the rearing phase, reducing feed quantity and costs of milk production. This fact is proven trough the reduction of necessary inputs for feeding during the rearing, impacting in reducing the cost of the production system and indirectly the cost of milk production

Feed efficiency of Nellore young bull in the feedlot.

The objective of the study was to evaluate feed efficiency of Nellore young bull in the feedlot using the evaluation of the residual feed intake (RFI). The experiment was carried out at the experimental farm Orestes Prata Tibery Júnior (ABCZ), located in Uberaba, MG, Brazil (lat. 19º 47' 68" S.; long. 47º 58' 50'' W, 788 m West). Nellore young bulls (n = 101), pure breed, with initial age of 17 months and mean live weight of 486 kg were housed in a feedlot containing electronic troughs and weighing scales. The experimental period lasted 98 days, with 28 of adaptation and 70 days of evaluation, from 03/17/2021 to 06/23/2021. The diet was formulated to provide 1.700 kg live weight/head/day and had a forage:concentrate ratio of 40:60, with 40% of corn silage and 60% of concentrate, containing 15.3% CP and 76.8% TDN on dry matter (DM) basis. The RFI was determined during the experimental period and the animals were separated in two experimental groups: positive and negative RFI. It was evaluated average daily gain (ADG), feed conversion (FC), daily dry matter intake (DMI) and gross feed efficiency (GFE). The experimental design was completely randomized and means were compared using Tukey test at 5% significance. In the evaluation of 101 young bulls, 56 had negative RFI and 45 had positive RFI, about 55.4% had lower DMI compared to estimated, which was considered the most efficient. The difference between the lowest and the highest individual intake followed was -1.87 kg (negative RFI) and 3.52 kg (positive RFI), with the difference of 5.39 kg of RFI, showing variability and chance of selection for more efficient and lower cost young bulls. It was observed effect of youn bull RFI group on DMI - 13.59 and 12.05 kg/day, and 2.51 and 2.24% LW, respectively for positive and negative RFI. There was a reduction of 11.3% in DMI during the experimental period. Feed conversion (6.28 and 6.93 kg of DM/kg ADG for negative and positive RFI) and GFE (0.16 and 0.15 kg ADG/kg DMI for negative and positive RFI) were influenced by RFI group. There was no effect (P>0.05) of RFI group on ADG - 1.95 (negative RFI) and 1.98 kg/head/day (positive RFI). Young bulls presenting negative RFI had lower intake with the same ADG, enabling better-feed conversion in the finishing phase, which directly affects the reduction of feed and production costs

Evaluation of the QuEChERS Method and Gas Chromatography–Mass Spectrometry for the Analysis Pesticide Residues in Water and Sediment

A method for the determination of pesticide residues in water and sediment was developed using the QuEChERS method followed by gas chromatography – mass spectrometry. The method was validated in terms of accuracy, specificity, linearity, detection and quantification limits. The recovery percentages obtained for the pesticides in water at different concentrations ranged from 63 to 116%, with relative standard deviations below 12%. The corresponding results from the sediment ranged from 48 to 115% with relative standard deviations below 16%. The limits of detection for the pesticides in water and sediment were below 0.003 mg L−1 and 0.02 mg kg−1, respectively