Identification of lptA, lpxE, and lpxO, Three Genes Involved in the Remodeling of Brucella Cell Envelope.

The brucellae are facultative intracellular bacteria that cause a worldwide extended zoonosis. One of the pathogenicity mechanisms of these bacteria is their ability to avoid rapid recognition by innate immunity because of a reduction of the pathogen-associated molecular pattern (PAMP) of the lipopolysaccharide (LPS), free-lipids, and other envelope molecules. We investigated the Brucella homologs of lptA, lpxE, and lpxO, three genes that in some pathogens encode enzymes that mask the LPS PAMP by upsetting the core-lipid A charge/hydrophobic balance. Brucella lptA, which encodes a putative ethanolamine transferase, carries a frame-shift in B. abortus but not in other Brucella spp. and phylogenetic neighbors like the opportunistic pathogen Ochrobactrum anthropi. Consistent with the genomic evidence, a B. melitensis lptA mutant lacked lipid A-linked ethanolamine and displayed increased sensitivity to polymyxin B (a surrogate of innate immunity bactericidal peptides), while B. abortus carrying B. melitensis lptA displayed increased resistance. Brucella lpxE encodes a putative phosphatase acting on lipid A or on a free-lipid that is highly conserved in all brucellae and O. anthropi. Although we found no evidence of lipid A dephosphorylation, a B. abortus lpxE mutant showed increased polymyxin B sensitivity, suggesting the existence of a hitherto unidentified free-lipid involved in bactericidal peptide resistance. Gene lpxO putatively encoding an acyl hydroxylase carries a frame-shift in all brucellae except B. microti and is intact in O. anthropi. Free-lipid analysis revealed that lpxO corresponded to olsC, the gene coding for the ornithine lipid (OL) acyl hydroxylase active in O. anthropi and B. microti, while B. abortus carrying the olsC of O. anthropi and B. microti synthesized hydroxylated OLs. Interestingly, mutants in lptA, lpxE, or olsC were not attenuated in dendritic cells or mice. This lack of an obvious effect on virulence together with the presence of the intact homolog genes in O. anthropi and B. microti but not in other brucellae suggests that LptA, LpxE, or OL β-hydroxylase do not significantly alter the PAMP properties of Brucella LPS and free-lipids and are therefore not positively selected during the adaptation to intracellular life

Aplikasi Herbisida 2,4-d Dan Penoxsulam Pada Pertumbuhan Dan Hasil Tanaman Padi Sawah (Oryza Sativa L.)

Salah satu teknik budidaya untuk meningkatkan produksi tanaman padi sawah yaitu dengan mengurangi persaingan antara tanaman dengan gulma. Pengendalian dengan kimiawi merupakan salah satu cara mengurangi pertumbuhan gulma di pertanaman padi. Cara kimiawi merupakan cara yang praktis, efektif dan efisien untuk mengendalikan gulma. Penelitian ini bertujuan untuk mempelajari pengaruh dari aplikasi herbisida 2,4-D dan penoxsulam dalam meningkatkan pertumbuhan dan hasil padi sawah serta menentukan dosis aplikasi herbisida 2,4-D dan penoxsulam baik secara tunggal maupun campuran dalam mengendalikan gulma pada tanaman padi sawah. Penelitian telah dilaksanakan pada bulan Maret-Juli 2014 di Desa Campurasri, Ngawi. Penelitian menggunakan Rancangan Acak Kelompok sederhana, dengan menempatkan 11 perlakuan yaitu H1 : kontrol herbisida 2,4-D; H2 : 2,4-D 11,25 kg ha-1; H3 : 2,4-D 22,5 kg ha-1; H4 : 2,4-D 33,75 kg ha-1; H5 : kontrol herbisida penoxsulam; H6 : penoxsulam 200 ml ha-1; H7 : penoxsulam 400 ml ha-1; H8 : penoxsulam 600 ml ha-1; H9 : 2,4-D 11,25 kg ha-1 dan penoxsulam 200 ml ha-1; H10 : 2,4-D 22,5 kg ha-1 dan penoxsulam 400 ml ha-1; H11 : 2,4-D 33,75 kg ha-1 dan penoxsulam 600 ml ha-1. Hasil penelitian menunjukkan bahwa perlakuan herbisida 2,4-D 11,25 kg ha-1 dan penoxsulam 200 ml menghasilkan bobot kering total tanaman dengan peningkatan sebesar 34,62 % dibandingkan dengan kontrol. Pada produksi tanaman padi peningkatan terjadi sebesar 29,77 % pada perlakuan herbisida 2,4-D 33,75 kg ha-1 dan penoxsulam 600 ml dibandingkan dengan kontrol

Avaliação de um extrato vegetal na dieta sobre o comportamento produtivo de suínos estressados pelo calor

The exposure of pigs to heat stress (HS) affects the integrity of intestinal epithelia, compared to thermal neutral (TN) pigs, partially due to overproduction of free radicals. Herbal extracts (HE) from Capsicum spp., Pipper nigrum y Zingiber officinales possess antioxidant activity. The effect of adding this HE to the diet was analyzed on performance of 42 pigs (27±3 kg). The treatments were: TN-C, TN pigs with control diet, TN-P, pigs with control diet plus 0.02% HE; HS-C, HS pigs with control diet; and HS-P, HS pigs with control diet plus 0.02% HE. The experiment consisted of two periods; in period 1, all pigs were adapted to the control diet during 8 days under TN conditions, followed by a 7-day experimental period. Daily weight gain and feed intake were higher (P <0.05), and feed conversion ratio tended (P<0.10) to improve in HS-HE pigs compared to HS-C pigs. In conclusion, adding HE to the diet can improve some productive parameters in pigs exposed to HS conditions.La exposición de cerdos a estrés por calor (EC), en comparación con termo neutralidad (TN) afecta la integridad del epitelio intestinal, en parte debido a la sobreproducción de radicales libres. Extractos de hierbas (EH) como Capsicum spp., Pipper nigrum y Zingiber officinales poseen actividad antioxidante. Se evaluó el efecto de adicionar un extracto EH a la dieta en el desempeño productivo de 42 cerdos (27±3 kg) en EC. Los tratamientos fueron: TN-T, cerdos en TN alimentados con dieta testigo; EC-T y EC-EH, cerdos en EC alimentados con dieta testigo sin o con 0.2 % de EH. El experimento consistió de dos periodos; en periodo 1, todos los cerdos tuvieron 8 días de adaptación a la dieta testigo en TN, seguido del periodo experimental de 7 días. La ganancia de peso y consumo de alimento fueron mayores (P <0.05), y la conversión alimenticia tendió a ser mejor (P<0.10) en cerdos EC-EH que en cerdos EC-T. En conclusión, la adición del EH puede contribuir a mejorar algunos parámetros productivos cuando los cerdos están expuestos a EC.A exposição de suínos ao estresse térmico (CE), em comparação com a termoneutralidade (TN), afeta a integridade do epitélio intestinal, em parte devido à superprodução de radicais livres. Extratos de ervas (EH) como Capsicum spp., Pipper nigrum e Zingiber officinales possuem atividade antioxidante. Avaliou-se o efeito da adição de extrato de EH à dieta sobre o desempenho produtivo de 42 suínos (27±3 kg) em EC. Os tratamentos foram: TN-T, suínos em TN alimentados com dieta controle; EC-T e EC-EH, suínos em EC alimentados com dieta controle sem ou com 0,2% de EH. O experimento consistiu em dois períodos; No período 1, todos os suínos tiveram 8 dias de adaptação à dieta controle em TN, seguido do período experimental de 7 dias. O ganho de peso e o consumo de ração foram maiores (P < 0,05) e a conversão alimentar tendeu a ser melhor (P < 0,10) em porcos EC-EH do que em porcos EC-T. Em conclusão, a adição de EH pode contribuir para melhorar alguns parâmetros produtivos quando os suínos são expostos a CE

Las redes como dispositivos para la gestión educativa en Iberoamérica

La presente aportación se focaliza en cómo el trabajo en red puede ayudar a mejorar la organización y gestión de los centros educativos. Presenta referentes normativos pero también identifica redes centradas en la gestión y pone ejemplos de alguna de ellas. Recoge las aportaciones de 36 especialistas, que han elaborado los informes de 11 países iberoamericanos

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Dietary α‐Linolenic Acid, Marine ω‐3 Fatty Acids, and Mortality in a Population With High Fish Consumption: Findings From the PREvención con DIeta MEDiterránea (PREDIMED) Study

Background: Epidemiological evidence suggests a cardioprotective role of α‐linolenic acid (ALA), a plant‐derived ω‐3 fatty acid. It is unclear whether ALA is beneficial in a background of high marine ω‐3 fatty acids (long‐chain n‐3 polyunsaturated fatty acids) intake. In persons at high cardiovascular risk from Spain, a country in which fish consumption is customarily high, we investigated whether meeting the International Society for the Study of Fatty Acids and Lipids recommendation for dietary ALA (0.7% of total energy) at baseline was related to all‐cause and cardiovascular disease mortality. We also examined the effect of meeting the society's recommendation for long‐chain n‐3 polyunsaturated fatty acids (≥500 mg/day). Methods and Results: We longitudinally evaluated 7202 participants in the PREvención con DIeta MEDiterránea (PREDIMED) trial. Multivariable‐adjusted Cox regression models were fitted to estimate hazard ratios. ALA intake correlated to walnut consumption (r=0.94). During a 5.9‐y follow‐up, 431 deaths occurred (104 cardiovascular disease, 55 coronary heart disease, 32 sudden cardiac death, 25 stroke). The hazard ratios for meeting ALA recommendation (n=1615, 22.4%) were 0.72 (95% CI 0.56–0.92) for all‐cause mortality and 0.95 (95% CI 0.58–1.57) for fatal cardiovascular disease. The hazard ratios for meeting the recommendation for long‐chain n‐3 polyunsaturated fatty acids (n=5452, 75.7%) were 0.84 (95% CI 0.67–1.05) for all‐cause mortality, 0.61 (95% CI 0.39–0.96) for fatal cardiovascular disease, 0.54 (95% CI 0.29–0.99) for fatal coronary heart disease, and 0.49 (95% CI 0.22–1.01) for sudden cardiac death. The highest reduction in all‐cause mortality occurred in participants meeting both recommendations (hazard ratio 0.63 [95% CI 0.45–0.87]). Conclusions: In participants without prior cardiovascular disease and high fish consumption, dietary ALA, supplied mainly by walnuts and olive oil, relates inversely to all‐cause mortality, whereas protection from cardiac mortality is limited to fish‐derived long‐chain n‐3 polyunsaturated fatty acids. Clinical Trial Registration URL: http://www.Controlled-trials.com/. Unique identifier: ISRCTN35739639