Unlocking the molecular realm: advanced approaches for identifying clinically and environmentally relevant bacteria.

Rapid, effective, and specific identification of clinical and environmental bacterial pathogens is of major importance for their control. Traditionally, bacteria have been identified by phenotypic methods based on morphological, biochemical, and metabolic properties. While these methods are very useful in clinical practice, they have limitations including a poor ability to differentiate within and between species and time-consuming workflows. Newly developed molecular methods can greatly improve the accuracy of taxonomic characterization, identifying specific strains of medical or environmental importance. However, due to high costs and the need for trained professionals, these methods are not yet routine in diagnostic laboratories. Thus, disseminating knowledge on advances in molecular identification techniques is pivotal to make these methodologies accessible. The objective of this work was to review and discuss current molecular techniques for bacteria identification aiming to track and monitor microbial agents in clinical and environmental samples.

Acute and chronic effects of the organophosphate malathion on the pancreatic α and ß cell viability, cell structure, and voltage-gated K+ currents.

Studies indicate that the pesticide malathion may have a role in diabetes. Herein, we determined the effects of different concentrations of malathion on survival, ultrastructure, and electrophysiologic islet cell parameters. Acutely, high concentrations of malathion (0.5 or 1 mM) increased cell death in rat islet cells, while low concentrations (0.1 mM) caused signs of cell damage in pancreatic α and ß cells. Exposure of RINm5F cells to malathion for 24 or 48 h confirmed the reduction in ß-cell viability at lower concentrations (0.001-100 µM). Chronic exposure of mouse pancreatic α and ß cells to 3 nM of malathion led to increased voltage-gated K+ (Kv) currents in α-cells. Our findings show a time and concentration dependency for the malathion effect on the reduction of islet cell viability and indicate that pancreatic α cells are more sensitive to malathion effects on Kv currents and cell death.

Unlocking the molecular realm: advanced approaches for identifying clinically and environmentally relevant bacteria

Rapid, effective, and specific identification of clinical and environmental bacterial pathogens is of major importance for their control. Traditionally, bacteria have been identified by phenotypic methods based on morphological, biochemical, and metabolic properties. While these methods are very useful in clinical practice, they have limitations including a poor ability to differentiate within and between species and time-consuming workflows. Newly developed molecular methods can greatly improve the accuracy of taxonomic characterization, identifying specific strains of medical or environmental importance. However, due to high costs and the need for trained professionals, these methods are not yet routine in diagnostic laboratories. Thus, disseminating knowledge on advances in molecular identification techniques is pivotal to make these methodologies accessible. The objective of this work was to review and discuss current molecular techniques for bacteria identification aiming to track and monitor microbial agents in clinical and environmental samples.

Bioinformatics and expression analysis of the Xeroderma Pigmentosum complementation group C (XPC) of Trypanosoma evansi in Trypanosoma cruzi cells / Análises de bioinformática e da expressão do gene Xeroderma Pigmentosum complementation group C (XPC) de Trypanosoma evansi em células de Trypanosoma cruzi

Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T. cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.

O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T. cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.

Bioinformatics and expression analysis of the Xeroderma Pigmentosum complementation group C (XPC) of Trypanosoma evansi in Trypanosoma cruzi cells

Abstract Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T.cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.

Resumo O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T.cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.

Bioinformatics and expression analysis of the Xeroderma Pigmentosum complementation group C (XPC) of Trypanosoma evansi in Trypanosoma cruzi cells / Análises de bioinformática e da expressão do gene Xeroderma Pigmentosum complementation group C (XPC) de Trypanosoma evansi em células de Trypanosoma cruzi

Abstract Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T.cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.

Resumo O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T.cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.

Osimertinib and anti-HER3 combination therapy engages immune dependent tumor toxicity via STING activation in trans.

Over the past decade, immunotherapy delivered novel treatments for many cancer types. However, lung cancer still leads cancer mortality, and non-small-cell lung carcinoma patients with mutant EGFR cannot benefit from checkpoint inhibitors due to toxicity, relying only on palliative chemotherapy and the third-generation tyrosine kinase inhibitor (TKI) osimertinib. This new drug extends lifespan by 9-months vs. second-generation TKIs, but unfortunately, cancers relapse due to resistance mechanisms and the lack of antitumor immune responses. Here we explored the combination of osimertinib with anti-HER3 monoclonal antibodies and observed that the immune system contributed to eliminate tumor cells in mice and co-culture experiments using bone marrow-derived macrophages and human PBMCs. Osimertinib led to apoptosis of tumors but simultaneously, it triggered inositol-requiring-enzyme (IRE1α)-dependent HER3 upregulation, increased macrophage infiltration, and activated cGAS in cancer cells to produce cGAMP (detected by a lentivirally transduced STING activity biosensor), transactivating STING in macrophages. We sought to target osimertinib-induced HER3 upregulation with monoclonal antibodies, which engaged Fc receptor-dependent tumor elimination by macrophages, and STING agonists enhanced macrophage-mediated tumor elimination further. Thus, by engaging a tumor non-autonomous mechanism involving cGAS-STING and innate immunity, the combination of osimertinib and anti-HER3 antibodies could improve the limited therapeutic and stratification options for advanced stage lung cancer patients with mutant EGFR.

Changes to objective structured clinical examinations (OSCE) at Australian medical schools in response to the COVID-19 pandemic.

INTRODUCTION: Objective Structured Clinical Examinations (OSCE) are used to assess clinical skills. We investigated how exit OSCEs changed in Australian medical schools in response to the COVID-19 pandemic. MATERIALS AND METHODS: The lead ACCLAiM assessment academic from 12 eligible Australian medical school members of the Australian Collaboration for Clinical Assessment in Medicine (ACCLAiM) received a 45-item semi-structured online questionnaire. RESULTS: All schools (12/12) responded. Exit OSCEs were not used by one school in 2019, and 3/11 schools in 2020. Of eight remaining schools, four reduced station numbers and testing time. The minimum OSCE testing time decreased from 64 min in 2019 to 54 min in 2020. Other modifications included: a completely online 'e-OSCE' (n = 1); hybrid delivery (n = 4); stations using: videos of patient encounters (n = 3), telephone calls (n = 2), skill completion without face-to-face patient encounters (n = 3). The proportion of stations involving physical examination reduced from 33% to 17%. Fewer examiners were required, and university faculty staff formed a higher proportion of examiners. CONCLUSIONS: All schools changed their OSCEs in 2020 in response to COVID-19. Modifications varied from reducing station numbers and changing delivery methods to removing OSCE and complete assessment re-structuring. Several innovative methods of OSCE delivery were implemented to preserve OSCE validity and reliability whilst balancing feasibility.

Bioinformatics and expression analysis of the Xeroderma Pigmentosum complementation group C (XPC) of Trypanosoma evansi in Trypanosoma cruzi cells.

Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T.cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.

Immunization against gonadotropin-releasing factor (GnRF) in market gilts: Effect on growth and carcass parameters, and impact of immunization timing.

Reproductive cycling in fattening gilts can be associated with undesirable effects, such as estrus-related aggressive behavior, reduced feed intake and, in production systems where gilts are co-housed with entire males, unwanted pregnancy. Immunization against Gonadotrophin Releasing Factor (IM) can temporarily suppress ovarian activity, including related negative consequences on animal welfare and productivity. Feed intake has been shown to be higher after IM, resulting in both increased growth and increased carcass fat. A series of studies was conducted to confirm these effects on production and look at their dynamics over time. Three trials were performed to a similar design, each involving 240 gilts divided into 4 experimental groups at 12 weeks of age. One group remained untreated while the others had the two dose, IM course completed 8, 6 or 4 weeks before harvest, which was on a single day at 24, 25 or 26 weeks of age depending on the study. Feed intake was measured daily and bodyweight weekly, allowing growth parameters to be calculated on a weekly basis and for specific longer periods. Carcass weight, backfat depth and lean meat percentage were recorded at harvest. No effects were observed before the second application of the immunological product (V2) and completion of the IM course. Starting in the second week after V2 all IM groups showed a marked and consistent increase in Average Daily Feed Intake (ADFI), typically peaking at over 120% of the control group 3 to 4 weeks after V2 and then slowly declining, but still remaining elevated at 8 weeks. Weekly Average Daily Gain (ADG) showed a similar pattern but with a faster decline, resulting in the initially favorable impact on feed efficiency becoming less favorable as the V2 to harvest interval (V2H) progressed. Carcass weights were higher in IM gilts and backfat depths were greater, with the effects increasing with increasing V2H. Correspondingly, carcass lean meat percentage tended to decrease, although the higher carcass weights meant that the absolute weight of lean meat remained similar or higher. Carcass yield was generally unaffected by IM, but some between-group differences were statistically significant, and it is possible that different factors predominated at different times after V2, creating a complex relationship with V2H duration. The optimum IM protocol will depend on local conditions and production objectives but, as a generalization and assuming ad libitum feeding, a shorter V2H will favor efficient growth, while a longer duration will maximize carcass changes, such as increased fat coverage. It is suggested that the growth performance changes seen after IM in gilts might be viewed as a process of adjustment to a heavier and fatter target body type.

High-resolution structural profile of hylaseptin-4: Aggregation, membrane topology and pH dependence of overall membrane binding process.

Hylaseptin-4 (HSP-4, GIGDILKNLAKAAGKAALHAVGESL-NH2) is an antimicrobial peptide originally isolated from Hypsiboas punctatus tree frog. The peptide has been chemically synthetized for structural investigations by CD and NMR spectroscopies. CD experiments reveal the high helical content of HSP-4 in biomimetic media. Interestingly, the aggregation process seems to occur at high peptide concentrations either in aqueous solution or in presence of biomimetic membranes, indicating an increase in the propensity of the peptide for adopting a helical conformation. High-resolution NMR structures determined in presence of DPC-d38 micelles show a highly ordered α-helix from amino acid residues I2 to S24 and a smooth bend near G14. A large separation between hydrophobic and hydrophilic residues occurs up to the A16 residue, from which a shift in the amphipathicity is noticed. Oriented solid-state NMR spectroscopy show a roughly parallel orientation of the helical structure along the POPC lipid bilayer surface, with an insertion of the hydrophobic N-terminus into the bilayer core. Moreover, a noticeable pH dependence of the aggregation process in both aqueous and in biomimetic membrane environments is attributed to a single histidine residue (H19). The protonation degree of the imidazole side-chain might help in modulating the peptide-peptide or peptide-lipid interactions. Finally, molecular dynamics simulations confirm the orientation and preferential helical conformation and in addition, show that HSP-4 tends to self-aggregate in order to stabilize its active conformation in aqueous or phospholipid bilayer environments.

Bases para um programa de controle da artrite encefalite caprina em rebanho leiteiro / [Bases for a program of control of caprine arthritis encephalite in dairy flock]

Objetivou-se avaliar um programa de controle da artrite encefalite caprina (AEC), por meio de testes diagnósticos sensíveis, separação de mãe e cria após o parto e medidas de manejo, com o intuito de formar rebanho livre do vírus. Utilizou-se um total de 47 cabritos da raça Saanen, mantidos isoladamente até o resultado dos primeiros testes de reação em cadeia de polimerase nested (PCR nested) e Western Blotting (WB), com base na coleta de sangue no momento do nascimento (M0). No PCR nested, quatro animais foram positivos, no M0, e foram eutanasiados. Posteriormente, os demais 43 cabritos foram submetidos à coleta de sangue aos 60 (M60) e 270 (M270) dias de vida para realização de novos testes de WB e PCR nested, que não detectaram animais positivos. Pode-se afirmar que a metodologia adotada neste estudo foi efetiva no controle da doença, nas fases de aleitamento e pós-aleitamento, e que a combinação do sistema de manejo, a fim de propiciar diminuição de risco de transmissão horizontal, com técnicas de diagnóstico mais apuradas, como o WB e a PCR nested, é relevante para elaboração de plano estratégico de controle da enfermidade.(AU)

We aimed to evaluate a program to control Caprine Arthritis Encephalitis (CAE), using diagnostic tests, separation of the mother and postpartum and other management measures, in order to form a free flock of the virus. We used a total of 47 Saanengoats in isolation until the results of the first nested Polymerase Chain Reaction (nested PCR) and Western Blotting (WB) tests, based on blood collection at the time of birth (M0). In the nested PCR, 4 animals were positive, at M0, and were eliminated. Later, the other 43goats were submitted to blood collection at 60 (M60) and 270 (M270) days of life to perform new tests of WB and nested PCR, which did not detect positive animals. We can affirm that the methodology adopted in this study was effective in the control of the disease, in the phase of breastfeeding and post-breastfeeding, and that the combination of the management system, which allows a reduction of risk of horizontal transmission, with more accurate diagnostic techniques, such as WB and nested PCR, is relevant for the elaboration of a strategic plan for the disease control.(AU)

Leaf application of chitosan and physiological evaluation of maize hybrids contrasting for drought tolerance under water restriction / Aplicação foliar de quitosana e avaliação fisiológica de híbridos de milho contrastantes para tolerância à seca sob restrição hídrica

Abstract It is a fact that the regions that cultivate the most maize crop do not have fully adequate technologies to measure productivity losses caused by irregularities in water availability. The objective of this study was to evaluate the physiological characteristics of maize hybrids tolerant (DKB 390) and sensitive (BRS 1030) to drought, at V5 growth stage and under water restriction, in order to understand the mechanisms involved in the induction of tolerance to drought by chitosan in contrasting maize genotypes. Plants were cultivated in pots at a greenhouse, and chitosan 100 ppm was applied by leaf spraying. The water restriction was imposed for 10 days and then leaf gaseous exchange and chlorophyll fluorescence were evaluated. The tolerant hybrid (DKB 390) showed higher photosynthesis, stomatal conductance, carboxylation efficiency, electron transport rate, and non-photochemical quenching when chitosan was used. Plants from tolerant genotype treated with chitosan were more tolerant to water stress because there were more responsive to the biopolymer.

Resumo As regiões que cultivam milho como cultura principal ainda não possuem tecnologias adequadas para mensurar as perdas na produtividade decorrentes na disponibilidade irregular de água. O objetivo desse estudo foi avaliar as características fisiológicas de híbridos de milho tolerante (DKB 390) e sensível (BRS1030) à seca, no estádio de crescimento V5 e sob restrição hídrica, para compreender os mecanismos envolvidos na indução de tolerância à seca pela quitosana em genótipos contrastantes. As plantas foram cultivadas vasos na casa de vegetação e a quitosana 100 ppm foi aplicada por pulverização foliar. A restrição hídrica durou 10 dias e foram avaliadas as trocas gasosas e a fluorescência da clorofila. O híbrido tolerante (DKB 390) apresentou maior fotossíntese, condutância estomática, eficiência de carboxilação, taxa de transporte de elétrons e quenching não fotoquímico quando aplicada a quitosana. As plantas do genótipo tolerante tratadas com quitosana foram mais tolerantes ao déficit hídrico porque foram mais responsivas ao biopolímero.

Herd-level factors associated with piglet weight at weaning, kilograms of piglets weaned per sow per year and sow feed conversion.

To understand the production factors that affect conclusive parameters of sow herd performance can improve the use of the resources and profitability of farm. The objective of this study was to identify associations and quantify the effects of a set of factors related to piglet weight at weaning (PWW), kilograms of piglets weaned per sow per year (kgPWSY) and sow feed conversion (SFC). Data from 150 farms were collected, for a total study population of 135 168 sows, including gilt replacement, breeding (mating), gestation and farrowing/lactation phases. A questionnaire focusing on reproductive performance, management, facilities, feeding, health and biosafety was administered. Multiple linear regression models were used to assess associations among factors with each of the three dependent variables. Increased duration of lactation was positively associated with PWW, kgPWSY and SFC. The increase in the number of live born pigs per litter was positively associated with kgPWSY and with SFC. Farms with higher PWW had farrowing room humidifiers, did not surgically castrate male piglets and used quaternary ammonia compounds for farrowing room disinfection. Farms with higher kgPWSY used lined ceilings in farrowing rooms and winter feeds with higher CP percentages in gestation; they also had more farrowings per sow per year. Sow feed conversion was worse in farms with partly slatted floors during gestation, in farms feeding lactating sows six times a day or ad libitum and farms with a higher sow-handler ratio. This study indicates that farms can increase PWW and kgPWSY and improve the SFC by changing one or more management, biosafety and feeding practices or facilities as well as by focusing on improving several performance parameters, particularly increasing the duration of lactation and the number of live born pigs per litter.

Leaf application of chitosan and physiological evaluation of maize hybrids contrasting for drought tolerance under water restriction.

It is a fact that the regions that cultivate the most maize crop do not have fully adequate technologies to measure productivity losses caused by irregularities in water availability. The objective of this study was to evaluate the physiological characteristics of maize hybrids tolerant (DKB 390) and sensitive (BRS 1030) to drought, at V5 growth stage and under water restriction, in order to understand the mechanisms involved in the induction of tolerance to drought by chitosan in contrasting maize genotypes. Plants were cultivated in pots at a greenhouse, and chitosan 100 ppm was applied by leaf spraying. The water restriction was imposed for 10 days and then leaf gaseous exchange and chlorophyll fluorescence were evaluated. The tolerant hybrid (DKB 390) showed higher photosynthesis, stomatal conductance, carboxylation efficiency, electron transport rate, and non-photochemical quenching when chitosan was used. Plants from tolerant genotype treated with chitosan were more tolerant to water stress because there were more responsive to the biopolymer.

Spectrally extended, near-surface refractive index determination: atomic layer deposited TiO2 on Si.

The optical performance of very thin films has always been difficult to measure, and it has been a gray area due to interface and coating imperfections. Atomic layer deposition has produced pinhole-free, continuous, and extremely pure Titania films, with precise control at monolayer level, on native oxide/Si substrates, whose atomic force microscopy imaged nano-topology is approximately followed. For interface probing, the Abelès method is extended to the visible spectrum, and Cauchy dispersion curves are fitted to the refractive index experimental data, showing excellent compatibility with ellipsometric analysis. This is possible with decreasing optical thickness until ∼1/10 quarterwave is reached, which sets a limit for the usual optical film behavior.

Oxidative stress and biomarker responses in the Atlantic halibut after long term exposure to elevated CO2 and a range of temperatures.

CO2 emissions from human activities are increasing, resulting in greater rates of change in the oceans, exceeding any other event in geological and historical records over the past 300 million years. Oceans are warming and pH levels are decreasing. Marine organisms will need to respond to multiple stressors and the potential consequences of global change-related effects in fish needs to be investigated. Fish are affected by many biotic and abiotic environmental variables, including temperature and CO2 fluctuations, and it is therefore critical to investigate how these variables may affect physiological and biochemical processes. We investigated the effects of elevated CO2 levels (pH of 8.0, which served as a control, or 7.6, which is predicted for the year 2100) combined with exposure to different temperatures (5, 10, 12, 14, 16, and 18 °C) in the Atlantic halibut (Hippoglossus hippoglossus) during a three month experiment. Since regulation of reactive oxygen species (ROS) is crucial for physiological processes the focus was on the antioxidant defense system and we assessed the effects on catalytic activities of antioxidant enzymes (SOD, CAT, GR, GST, GPx). In addition we also analyzed effects on cholinesterase enzymes (AChE and BChE), and CYP1A enzyme activities (EROD). The treatments resulted in oxidative stress, and damage was evident in the form of protein carbonyls which were consistently higher in the elevated CO2-treated fish at all temperatures. Analyses of antioxidant enzymes did not show the same results, suggesting that the exposure to elevated CO2 increased ROS formation but not defences. The antioxidant defense system was insufficient, and the resulting oxidative damage could impact physiological function of the halibut on a cellular level.

Heritability and genotype-environment interactions for growth curve parameters in meat-type quail fed different threonine:lysine ratios from hatching to 21 d of age.

The aim of the present study was to estimate heritabilities and evaluate the existence of genotype-environment interactions for growth curve parameters in quail fed diets containing different threonine:lysine ratios. A total of 4,441 body weight information from two genetic quail groups (LF1 and LF2) fed diets containing 0.66%, 0.71%, 0.76%, 0.81%, and 0.86% threonine:lysine ratios from hatching to 21 d of age were evaluated. From 22 to 35 d of age, quail received a single diet. The Gompertz model was used to estimate growth curve parameters. Genetic analyses were performed using random regression models, by Legendre polynomials of the second kind, considering homogeneity of residual variances. The following characteristics were evaluated: asymptotic weight, asymptotic growth rate, and inflection point. Increases in threonine:lysine ratios promoted higher heritability estimates for these variables in the LF1 genetic group compared to LF2, which indicates that the additive genetic variation was modified due to the environmental variation influenced by the evaluated amino acid ratios, with differences between both genetic groups. Thus, it is recommended that quail be selected in the 0.86% ratio in genetic group LF1 and 0.66% in genetic group LF2, where greater heritabilities were observed. Dispersion of individual breeding values along the environmental gradient was observed for all evaluated characteristics, in both genetic groups, suggesting the existence of genotype-environment interactions for these variables. The evaluated amino acid ratios should be considered in quail breeding programs, since breeding value predictions for a determined threonine:lysine ratio are not valid for other ratios.

Effects of saxagliptin on adipose tissue inflammation and vascular function in overweight and obese people: a placebo-controlled study.

AIMS: To test the effect of the dipeptidyl peptidase-4 inhibitor saxagliptin on adipose tissue inflammation and microvascular function, and whole-body postprandial endothelial function. METHODS: A randomized, double-blind, placebo-controlled, parallel study was conducted between June 2013 and November 2016 in 44 overweight or obese people without diabetes (saxagliptin, n=28; placebo, n=16). Subcutaneous abdominal adipose tissue biopsies, a 4-h fat-enriched meal test and peripheral arterial tonometry for measurement of endothelial function were performed at baseline and after 6 weeks of treatment with saxagliptin (5 mg/day) or matching placebo. RESULTS: Forty participants were analysed (saxagliptin, n=26; placebo, n=14). Secretion of interleukin-8 from adipose tissue explants was reduced after saxagliptin (median fold-change from baseline: 0.8 saxagliptin vs 3.3 placebo; P=0.02). Adipose tissue expression of thioredoxin-inhibitory protein (TxNIP) was lower after saxagliptin (0.75 vs 1.0; P=0.02), while there were no significant differences in adipose tissue secretion of interleukin-1b, interleukin-6 or macrophage chemoattractant protein 1 (MCP-1), adipose tissue macrophage content, adipose tissue mRNA levels of mcp1, cd36, cd68, il6, il8, txnip and adpq, and activation of adipose tissue inflammatory pathways [extracellular signal-regulated kinase, c-Jun N-terminal kinase (JNK) and nuclear factor-κB (NF- κB)] or insulin-induced vasodilation of adipose tissue arterioles. Postprandial plasma glucose was slightly lower (by an estimated 0.3 mmol/l; P=0.01), while postprandial insulin, triglyceride levels and endothelial function were unchanged after saxagliptin. CONCLUSIONS: The effect of saxagliptin on adipose tissue inflammation was relatively modest, with many inflammatory markers unchanged. We also found no evidence that saxagliptin therapy improved adipose tissue arteriole vasodilation or postprandial endothelial function.

Performance, health and physiological responses of newly weaned feedlot cattle supplemented with feed-grade antibiotics or alternative feed ingredients.

With increased regulations regarding the use of feed-grade antimicrobials in livestock systems, alternative strategies to enhance growth and immunity of feedlot cattle are warranted. Hence, this experiment compared performance, health and physiological responses of cattle supplemented with feed-grade antibiotics or alternative feed ingredients during the initial 60 days in the feedlot. Angus×Hereford calves (63 steers+42 heifers) originating from two cow-calf ranches were weaned on day -3, obtained from an auction yard on day -2 and road-transported (800 km; 12 h) to the feedlot. Upon arrival on day -1, shrunk BW was recorded. On day 0, calves were ranked by sex, source and shrunk BW, and allocated to one of 21 pens. Pens were assigned to receive (7 pens/treatment) a free-choice total mixed ration containing: (1) lasalocid (360 mg/calf daily of Bovatec; Zoetis, Florham Park, NJ, USA)+chlortetracycline (350 mg/calf of Aureomycin at cycles of 5-day inclusion and 2-day removal from diet; Zoetis) from days 0 to 32, and monensin only (360 mg/calf daily of Rumensin; Elanco Animal Health, Greenfield, IN, USA) from days 33 to 60 (PC), (2) sodium saccharin-based sweetener (Sucram at 0.04 g/kg of diet dry matter; Pancosma SA; Geneva, Switzerland)+plant extracts containing eugenol, cinnamaldehyde and capsicum (800 mg/calf daily of XTRACT Ruminants 7065; Pancosma SA) from days 0 to 32 and XTRACT only (800 mg/calf daily) from days 33 to 60 (EG) or (3) no supplemental ingredients (CON; days 0 to 60). Calves were assessed for bovine respiratory disease (BRD) signs and dry matter intake was recorded from each pen daily. Calves were vaccinated against BRD pathogens on days 0 and 22. Shrunk BW was recorded on day 61, and blood samples collected on days 0, 6, 11, 22, 33, 43 and 60. Calf ADG was greater (P=0.04) in PC v. EG and tended (P=0.09) to be greater in PC v. CON. Feed efficiency also tended (P=0.09) to be greater in PC v. CON, although main treatment effect for this response was not significant (P=0.23). Mean serum titers against bovine respiratory syncytial virus were greater in EG v. PC (P=0.04) and CON (tendency; P=0.08). Collectively, the inclusion of alternative feed ingredients prevented the decrease in feed efficiency when chlortetracycline and ionophores were not added to the initial feedlot diet, and improved antibody response to vaccination against the bovine respiratory syncytial virus in newly weaned cattle.