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This systematic review analyzed the effect of selected nutrients and additives in the feed of pregnant sows on the survival of newborn piglets. We analyzed 720 peer-reviewed publications in English in PubMed® and Web of Science®, dated July 2023 to January 2024, related to the effect of dietary supplementation with fatty acids and various percentages of protein, amino acids, and/or sources of dietary fiber on the offspring of gestating sows. While several papers evaluated the effect of nutrition on gestating sows, only a few delved into the distinct feeding strategies required at each stage of gestation to meet the NRC's nutritional requirements for maternal tissue gain and postnatal neonatal survival and growth. This body of research suggests that as gestation progresses the sow's nutritional requirements increase, as the NRC established, to satisfy their own metabolic needs and those of their fetuses. Additional research is needed to determine an optimal feeding strategy.

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Background and Aim: Working animals are important in agriculture because they play a role in various agricultural activities, including milk and meat production. Thus, they contribute to the development of rural communities. In this study, we aimed to evaluate the effects of different load weights on the work performance and the physiological and hematological responses of working water buffalo (Bubalus bubalis). Materials and Methods: The work performances of 12 buffaloes (average weight 782.16 ± 21.62 kg) transporting 200, 350, and 500 kg of African palm fruits in metal baskets placed on their backs were evaluated. Work performance variables evaluated immediately after work were as follows: total number of trips (n), total weight (kg), distance traveled (km/day), working period (h), stopped time (h), and average speed (km/h). In addition, we evaluated physiological, biochemical, and hematological variables at three different times: before the start of work, immediately after work, and on the rest day. Results: Among the load weights, 500 kg (total load carried = 4,138.88 kg) improved work efficiency compared to 200 kg loads (total load = 3,322.22 kg) (p = 0.0281). However, 500 kg loads resulted in slower average speed (2.4 km, p = 0.0164), shorter working period (2.39 h, p < 0.0001) and distance traveled (7.29 km, p < 0.0001), and less total number of trips (8.27 trips, p < 0.0001) compared to 350 and 200 kg load weights (3.45 and 3.52 km/h, 2.55 and 2.79 h, 8.71 and 9.75 km, 10.94 and 16.61 trips, respectively); and the heaviest loads resulted in significantly higher (p < 0.005) respiratory rate, pulse, heart rate, rectal temperature, glucose, lactate dehydrogenase, creatine kinase, total protein, white blood cell count, neutrophils, lymphocytes, monocytes, eosinophils, and basophils. In contrast, was associated with lower levels of red blood cells, hemoglobin, and hematocrit compared to lower loads. All differences were more pronounced in 500 kg (p < 0.005) compared to 200 kg loads. Conclusion: Working buffaloes responded to work related to the transport of African palm fruits through various physiological, biochemical, and hematological changes. However, some variables remained close to the reference values reported in the literature for water buffaloes, and in general, all variables were reestablished during the rest day, indicating that these animals have adapted to working conditions.

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The development of agroecology has promoted the discovery of new bioactive compounds that might act as biocides to control infections and microbial contamination. Algae belonging to Lyngbya genus produce several allelochemicals, which are compounds with crop protection potential. The present study aimed to examine primary and secondary compounds derived from Lyngbya sp. extracts (aqueous and hydroethanolic) on phytotoxic, cytogenotoxic, and insecticidal activities. Determination of compounds indicated the presence predominantly of proteins and flavonoids. The extracts presented physicochemical characteristics that produced (1) 89% germination inhibition using hydroethanolic extract and (2) diminished development of seedlings of L. sativa by hydroethanolic extract as evidenced by reduced radicles length in 83.54%. Aqueous and hydroethanolic Lyngbya sp. extracts significantly interfered with meristematic cells of A. cepa, as evidenced by chromosomal alterations and aberrant mitotic phases in cells. Extracts also exhibited pro-oxidative activity and a potent insecticidal potential on S. zeamais, indicating that the hydroethanolic extract produced 100% insect mortality at 75 mg/ml after 48 hr while the aqueous extract initiated 90% mortality at the same concentration after 82 hr. Therefore, data demonstrate that Lyngbya genus provides basic information for new environmental and ecotoxicological studies to seek a possible source of proteins and flavonoids to be used in agroecological management.

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Objetivo: identificar se há uma Teoria de Enfermagem cujos elementos que integram seu metaparadigma são coerentes com os conceitos a eles atribuídos por membros que compõem um Serviço de Enfermagem do Trabalho e aqueles identificados na literatura dessa área de atuação profisisonal. Métodos: estudo metodológico com análise descritiva. Resultado: as "pessoas" que demandam cuidados no serviço são os servidores; "saúde" refere-se ao bem-estar psicobiológico, social e espiritual; à "Enfermagem" cabe a prevenção de agravos, promoção e recuperação da saúde e reabilitação; "ambiente" refere-se ao espaço físico do trabalhador. Após mapeamento entre os conceitos do metaparadigma da teoria mais conhecida pelos servidores, com os que emergiram de suas respostas e aqueles identificados na literatura da área, houve a seleção e validação de uma teoria para essa área de atuação. Conclusão: conceitos do metaparadigma da Teoria das Necessidades Humanas Básicas são coerentes com ações executadas pela Enfermagem do Trabalho.

Objective: to identify whether there is a nursing theory whose elements making up its metaparadigm are consistent with the concepts attributed to them by members at an occupational health nursing service and the concepts identified in the literature of this area. Methods: methodological study with a descriptive analysis. Results: the "people" who demand care at the service are civil servants; "health" Abstract refers to psychobiological, social, and spiritual well-being; "nursing" involves the prevention of complications, health promotion and recovery, and rehabilitation; and "environment" pertains to the physical space of workers. After mapping the concepts of the metaparadigm of the theory most known by civil servants, with those that emerged from their answers, and those identified in the literature in this field, a theory for this area of activity was selected and validated. Conclusion: concepts of the metaparadigm of the Basic Human Needs Theory are consistent with actions carried out by occupational health nurses.

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The giant extracellular hemoglobin of the annelid Glossoscolex paulistus (HbGp; 3.6 MDa) is a valuable and underexplored supramolecular hemoprotein system for the biorecognition of reactive oxygen species. In this work, an efficient and simple electrochemical platform was designed for analyzing H2O2, using HbGp covalently immobilized on Nafion®-modified glassy carbon electrode, named as HbGp/Nafion/GCE. Voltammetric and spectroscopic studies revealed the importance of prior modification of the electrodic support with the conducting polymer to obtain satisfactory hemoglobin electroactivity, as well as a biocompatible microenvironment for its immobilization. In terms of biological activity, it was observed a greater reactivity of the biomolecule in acidic medium, enabling the detection of the analyte by a quasi-reversible mechanism, whose kinetics was limited by analyte diffusion. In the presence of H2O2, the native structure of hemoglobin (oxy-HbGp (Fe2+)) oxidizes to ferryl-HbGp (Fe4+) and this redox reaction can be monitored on HbGp/Nafion/GCE with a detection limit of 8.5 × 10‒7  mol L-1. In addition to high sensitivity, the electrochemical biosensor also provided reproducible, consistent, and accurate measurements. The electroanalytical method showed an appropriate performance to quantify different levels of H2O2 in milk samples, proving the potential of HbGp/Nafion/GCE for this purpose.

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This study aimed to investigate antigenotoxicity and antioxidant potential of extract, fractions and vitexin from C. antisyphiliticus. Methanolic extract was fractionated through solvents of increasing polarity. The composition of extracts and fractions were evaluated through phytochemical screening. Micronucleus test was performed in mice to evaluate the antigenotoxicity. Antioxidant activity was measured using the assay 1,1-diphenyl-2-picrylhydrazyl (DPPH), iron ion chelating, thiobarbituric acid assay and nitric oxide scavenging. Treatment with extract, fractions and vitexin did not produce an increase in Micronucleus mean values. However, Micronucleus (MN) mean values decreased in relation to control. methanolic extract presented antioxidant potential for DPPH (81%), iron ion chelating (77.8%), Thiobarbituric Acid (TBARS) (32.49%) and Nitric Oxide (NO) (80.97%). Ethyl acetate fraction showed the highest antioxidant activity (65.46%). The vitexin showed a Inhibitory Concentration (IC50) of DPPH value smaller in relation to control. Vitexin flavonoid was detected by High Performance Liquid Chromatography (HPLC), infrared spectrometry and nuclear magnetic resonance. It can be inferred that methanolic extract, fraction ethyl acetate and vitexin isolated from C. antisyphiliticus is endowed with antigenotoxic and antioxidant potential.

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A raça Dálmata é uma das raças mais populares, e, de acordo com seu padrão racial, deve apresentar cor de pelagem branca, com pintas pretas ou fígado. Vários loci estão envolvidos na determinação da cor da pelagem dos cães. No Dálmata, os principais são o locus B e o locus E, pois esses lócus têm influência um sobre o outro, causando uma interação gênica chamada epistasia, onde o efeito de um gene modifica o efeito de outro, alterando o fenótipo do animal. Com o avanço da cinofilia, o melhoramento genético em cães se tornou mais importante, tornando o conhecimento desses genes uma ferramenta necessária para os criadores. O objetivo deste trabalho foi demonstrar a importância do teste genético para o gene E, e seu auxílio no planejamento de acasalamento nos canis de Dálmatas. Para isso, foi usada uma ninhada nascida em Fortaleza, na qual foram realizados testes genéticos para o gene E do padreador de pintas pretas e de dois filhotes escolhidos aleatoriamente, um preto e um limão. O teste foi realizado através da técnica de PCR, e como resultado foi visto que o pai é heterozigoto (Ee). Já em relação as crias, foi confirmado o homozigoto dominante (EE) para a cria dentro do padrão e o homozigoto recessivo (ee) para a cria limão. Nesta cria ocorreu a epistasia, fazendo com que apresentasse pintas alaranjadas. Assim, conclui-se que não se pode definir o genótipo apenas pelo fenótipo, tornando o teste genético uma importante ferramenta para escolha dos padreadores.(AU)

The Dalmatian breed is one of the most popular breeds, and, according to its racial pattern, should have a white coat color with black spots or liver. Several loci are involved in determining the coat color of dogs. In the Dalmatian, the major are the locus B and the locus E, because these locus have influence on each other, causing a genetic interaction called epistasis, where the effect of one gene modifies the effect of another, altering the phenotype of the animal. With the advancement of cynophilia, genetic improvement in dogs has become more important, making knowledge of these genes a necessary tool for breeders. The objective of this work was to demonstrate the importance of the genetic test for gene E, and its aid in the planning of mating in dalmatians kennels. For this, a litter born in Fortaleza was used, in which genetic tests were performed for the E gene of the black-spotted and two randomly selected puppies, one black and one lemon. The test was performed using the PCR technique, and as a result it was seen that the parent is heterozygous (Ee). In relation to the offspring, the dominant homozygous (EE) was created for the offspring and the recessive homozygote (ee) for the offspring. In this breed epistasis occurred, causing it to present orange spots. Thus, it can be concluded that the genotype can not be defined only by the phenotype, making the genetic test an important tool for the selection of stud holders.(AU)

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A raça Dálmata é uma das raças mais populares, e, de acordo com seu padrão racial, deve apresentar cor de pelagem branca, com pintas pretas ou fígado. Vários loci estão envolvidos na determinação da cor da pelagem dos cães. No Dálmata, os principais são o locus B e o locus E, pois esses lócus têm influência um sobre o outro, causando uma interação gênica chamada epistasia, onde o efeito de um gene modifica o efeito de outro, alterando o fenótipo do animal. Com o avanço da cinofilia, o melhoramento genético em cães se tornou mais importante, tornando o conhecimento desses genes uma ferramenta necessária para os criadores. O objetivo deste trabalho foi demonstrar a importância do teste genético para o gene E, e seu auxílio no planejamento de acasalamento nos canis de Dálmatas. Para isso, foi usada uma ninhada nascida em Fortaleza, na qual foram realizados testes genéticos para o gene E do padreador de pintas pretas e de dois filhotes escolhidos aleatoriamente, um preto e um limão. O teste foi realizado através da técnica de PCR, e como resultado foi visto que o pai é heterozigoto (Ee). Já em relação as crias, foi confirmado o homozigoto dominante (EE) para a cria dentro do padrão e o homozigoto recessivo (ee) para a cria limão. Nesta cria ocorreu a epistasia, fazendo com que apresentasse pintas alaranjadas. Assim, conclui-se que não se pode definir o genótipo apenas pelo fenótipo, tornando o teste genético uma importante ferramenta para escolha dos padreadores.

The Dalmatian breed is one of the most popular breeds, and, according to its racial pattern, should have a white coat color with black spots or liver. Several loci are involved in determining the coat color of dogs. In the Dalmatian, the major are the locus B and the locus E, because these locus have influence on each other, causing a genetic interaction called epistasis, where the effect of one gene modifies the effect of another, altering the phenotype of the animal. With the advancement of cynophilia, genetic improvement in dogs has become more important, making knowledge of these genes a necessary tool for breeders. The objective of this work was to demonstrate the importance of the genetic test for gene E, and its aid in the planning of mating in dalmatians kennels. For this, a litter born in Fortaleza was used, in which genetic tests were performed for the E gene of the black-spotted and two randomly selected puppies, one black and one lemon. The test was performed using the PCR technique, and as a result it was seen that the parent is heterozygous (Ee). In relation to the offspring, the dominant homozygous (EE) was created for the offspring and the recessive homozygote (ee) for the offspring. In this breed epistasis occurred, causing it to present orange spots. Thus, it can be concluded that the genotype can not be defined only by the phenotype, making the genetic test an important tool for the selection of stud holders.

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Intra-partum asphyxia is the most common non-infectious etiology limiting the performance of neonate piglets. Previous studies indicate caffeine (orally and subcutaneously) reverses the effects of intra-partum asphyxia in neonate piglets. In this study, there was investigation of whether use of a novel therapeutic protocol for administering caffeine subcutaneously to pregnant sows would improve the newborn piglets' vitality, physio-metabolic profiles and body weight gain. Sows were randomly divided into two groups (n = 10 each). Caffeine or NaCl 0.9% was administered 2 days pre-farrowing. Physio-metabolic profiles were measured using blood from the anterior vena cava. The vitality of piglets was evaluated immediately after birth. Piglets (n = 180) were weighed at birth and on days 7, 14 and 21 of lactation. Caffeine positively affected the vitality of the piglets, as indicated by greater vitality scores than that for the control group (8.72 ±â€¯0.12 compared with 7.28 ±â€¯0.16, P < 0.001). Metabolic values were similar between groups, but pO2 values were greater in the piglets with greater vitality scores treated with caffeine (19.10 ±â€¯0.82 compared with 14.49 ±â€¯1.42, P < 0.01), indicating increased respiratory rates. Body weight gain at day 21 was greater in the piglets treated with caffeine that had greater vitality scores than the control piglets having greater vitality scores (6.87 ±â€¯0.18 compared with 6.52 ±â€¯0.25 kg, P < 0.05). Caffeine administration before birth improves the vitality and respiratory capacity of piglets, increasing their adaptation to extra-uterine environment.

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This study presents multiwall and bamboo-like carbon nanotubes found in samples from the Allende carbonaceous chondrite using high-resolution transmission electron microscopy (HRTEM). A highly disordered lattice observed in this material suggests the presence of chiral domains in it. Our results also show amorphous and poorly-graphitized carbon, nanodiamonds, and onion-like fullerenes. The presence of multiwall and bamboo-like carbon nanotubes have important implications for hypotheses that explain how a probable source of asymmetry in carbonaceous chondrites might have contributed to the enantiomeric excess in soluble organics under extraterrestrial scenarios. This is the first study proving the existence of carbon nanotubes in carbonaceous chondrites.

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The horse welfare at markets includes fatigue, fear, fasting, dehydration and injuries. However, the scientific literature contains no readily-available information on the physiology responses of equids sold in livestock markets. The objective of the present study was to evaluate the effect of holding in livestock markets on gas exchange, the acid-base balance, energy metabolism, and the mineral and water balance in 4 types of horses (Equus caballus), donkeys (Equus asinus) and mules ((Equus asinus × Equus caballus). To this end, a total of 1,438 equine were utilized, after classification into six groups, as follows: mules, donkeys, culled horses, charrería horses (Mexican rodeo horses), foals, and ponies. The time intervals evaluated were 1 and 5 h. During the study, the animals received only water ad libitum. The physiological blood indicators assessed were: PvCO2 (mm Hg) and PvO2 (mm Hg) pressure, pH, glucose (mg/dL), lactate (mg/dL), bicarbonate levels (mmol/L), hematocrit (%), Na+, K+ and Ca2+ (mmol/L). The animals that presented the most marked physiological alterations were the mules and donkeys. The mules that remained in the corrals for 1 h presented increases (P < 0.0001) in the values for pO2, glucose, hematocrit and blood pH, compared to reference values (RV), while the donkeys had increases (P < 0.0001) in glucose and hematocrit values. By the end of the first hour at the exhibition corrals the equine were dehydrated, suffered fatigue, and suffered metabolic and compensatory problems, probably due to the combined effects of a series of factors that include transport and inadequate handling.

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Objetivo: identificar os fatores facilitadores e dificultadores dos atendimentos realizados pelas equipes do grupo de resgate voluntário, “Anjos do Asfalto”. Método: Estudo quantitativo descritivo, realizado com 16 integrantes do resgate voluntário “Anjos do Asfalto”, em Minas Gerais. Os dados foram coletados por meio de um questionário estruturado autoaplicável com questões sociodemográficas e sobre fatores que facilitam ou dificultam a atuação da equipe. Resultados: A maioria dos respondentes (75,0%) foi do sexo masculino. A idade variou de 30 a 51 anos, com média de 38,3 anos. Quanto à formação profissional, a maioria (46,1%) é composta por enfermeiros. A média do tempo de atuação no serviço é de 3,3 anos. Os principais fatores facilitadores foram: experiência e conhecimento profissional dos integrantes, apoio de outras entidades e trabalho e integração em equipe. Já os fatores dificultadores foram: alto custo para manutenção do projeto e a escassez de recursos financeiros. Conclusão: O estudo mostrou que os fatores facilitadores destacados pelo grupo são uma junção de conquistas alcançadas durante os anos de atuação. Em contrapartida, a falta de verba, patrocínio e apoio governamental podem comprometer a atuação desse grupo que traz grandes contribuições para o atendimento das vítimas em situação de urgência e emergência.

Objective: to identify the factors facilitating and hindering the attendance of the teams of the voluntary rescue group, "Anjos do Asfalto". Method: Descriptive quantitative study, carried out with 16 members of the voluntary rescue "Anjos do Asfalto", in Minas Gerais. The data were collected through a self-administered structured questionnaire with sociodemographic questions and factors that facilitate or hinder the team's performance. Results: The majority of respondents (75.0%) were male. The age ranged from 30 to 51 years, with a mean of 38.3 years. Regarding vocational training, the majority (46.1%) are nurses. The average duration of the service is 3.3 years. The main facilitating factors were: experience and professional knowledge of the members, support of other entities and work and integration in a team. On the other hand, the difficult factors were: high cost to maintain the project and scarce financial resources. Conclusion: The study showed that the facilitating factors highlighted by the group are a combination of accomplishments achieved during the years of performance. On the other hand, the lack of funds, sponsorship and government support can jeopardize the performance of this group that brings great contributions to the care of the victims in a situation of urgency and emergency.

Objetivo: identificar los factores que facilitan y dificultan los atendimientos realizados por los equipos de rescate voluntario “Ángeles del Asfalto”. Método: Estudio cuantitativo descriptivo, realizado con 16 integrantes del rescate voluntario “Ángeles del Asfalto”, en Minas Gerais, Brasil. La recolección de datos ha sido realizada por medio de un cuestionario estructurado auto aplicable con cuestiones sociodemográficas y sobre factores que facilitan o dificultan la actuación del equipo. Resultados: La mayoría de las personas que respondieron (75,0%) son varones. La edad ha variado entre los 30 y los 51 años, y la edad media ha sido de 38,3 años. En relación a la formación profesional, el grupo reúne en su mayoría, enfermeros (46.1%). El tiempo medio de estancia en el trabajo es de 3.3 años. Los participantes han dicho que los principales factores para facilitar su trabajo han sido la experiencia y el conocimiento profesional de los integrantes, apoyo de otras organizaciones y trabajo e integración en equipo. Sin embargo, la mayor y más predominante dificultad ha sido el alto coste para mantener el proyecto y la falta de recursos financieros. Conclusión: El estudio mostró que los factores facilitadores apuntados por el grupo son una suma de conquistas logradas a lo largo de los años de trabajo del equipo. Sin embargo, la falta de verba, patrocinio y apoyo gubernamental pueden comprometer la actuación de ese grupo que contribuye muchísimo en lo que se refiere a la atención a las víctimas en situaciones de urgencia y emergencia en el estado de Minas Gerais.

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The main objective of this study was to investigate the daily intake of chlorogenic acids (CGAs) and methylxanthines by consumers of maté traditional beverages (MTBs), terere and chimarrão (Ilex paraguariensis A.St.-Hill). In the studied population (450 citizens from Toledo, PR, Brazil), 63% consume the chimarrão and 37% terere, with weighted mean daily intakes estimated at 648-2160 and 244-746 mL, respectively. For every 100 mL of beverage consumed, the average amount of total phenol compounds extracted was 673.6 mg for chimarrão and 1184.9 mg for terere. Regarding CGAs composition, caffeoylquinic acids (CQAs) constitute about 38.4% for chimarrão and 55.3% for terere, and dicaffeoylquinic acids (diCQAs) represent 61.6 and 44.7% of the extracted compounds, respectively. The daily intake of phenolic compounds by MTB consumers was estimated for chimarrão (512.5-1708.5 mg/day) and terere (583.0-1779.7 mg/day). These results allow us to conclude that MTBs are important dietary sources of CGAs, mainly CQAs and di-CQAs.

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BACKGROUND: Ilex paraguariensis A. St. Hil. var. paraguariensis (Aquifoliaceae) popularly known as 'mate' is an important species native to South America. Despite numerous studies showing significant antioxidant and lipid lowering properties, the antiatherosclerotic mechanisms of this species remain unknown. PURPOSE: To evaluate the possible antiatherosclerotic effects of a butanolic fraction (n-BFIP) obtained from I. paraguariensis and to investigate the molecular mechanisms involved in this activity. METHODS: First, n-BFIP was obtained from the hydroalcoholic extract and a detailed phytochemical investigation about its main secondary metabolites was performed. Then, during 8 experimental weeks, rabbits received diet supplemented with 1% cholesterol (CRD). After 4 weeks of CDR, animals were redistributed into five groups (n = 6) and treated (p.o.) with n-BFIP (10, 30 and 100 mg/kg), simvastatin (5 mg/kg), or vehicle (filtered water, 1 ml/kg) once daily for 4 weeks. An additional group was fed with cholesterol-free diet and treated with vehicle. At the end of 8 weeks, serum samples were obtained for the measurement of serum lipids, lipid and protein oxidation and indirect nitric oxide levels. In addition, serum IL-1ß, IL-6, sICAM-1, sVCAM-1, and intracellular cGMP levels in rabbit aortic rings were measured. Samples from the aortic arch and thoracic segment were collected for histopathological analysis. RESULTS: CRD induced oxidative and nitrosative stress and increased serum lipids, IL-1ß, IL-6, sICAM-1, and sVCAM-1 levels. In addition, structural changes in the intima layers of different arterial branches were also found. Although it did not change serum lipids, n-BFIP reverted oxidative and nitrosative stress and reduced IL-1ß, IL-6, sICAM-1, and sVCAM-1 levels, besides to increasing intracellular levels of cGMP in vitro. In addition, the formation of atherosclerotic plaques was reduced to values close to those of animals fed with cholesterol-free diet. CONCLUSIONS: A 4-week n-FBIP treatment reduces the progression of the atherosclerotic disease in New Zealand rabbits. These effects are associated with an attenuation of oxidative and nitrosative stress, affecting IL-1ß, IL-6, sICAM-1 and sVCAM-1 levels.

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Oxy-HbRa thermal stability was evaluated by dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS) at pH 5.0, 7.0, 8.0, and 9.0. DLS results show that oxy-HbRa, at pH 7.0 and 5.0, remains stable up to 56 °C, undergoing denaturation/aggregation in acidic media above 60 °C, followed by partial sedimentation of aggregates. At alkaline pH values 8.0 and 9.0, oxy-HbRa oligomeric dissociation is observed above 30 °C, before denaturation. SAXS data show that oxy-HbRa, at 20 °C, is in its native form, displaying radius of gyration (R g) and particle maximum dimension (D max) of 108 ± 1 and 300 ± 10 Å, respectively. Oxy-HbRa, at pH 7.0, undergoes denaturation/aggregation at 60 °C. At pH 5.0-6.0, HbRa thermal denaturation/aggregation start earlier, at 50 °C, accompanied by an increase of R g and D max values. However, an overlap of oligomeric dissociation and denaturation in the system is observed upon temperature increase, with an increase in R g and D max. Analysis of experimental p(r) curves as a linear combination of theoretical curves obtained for HbGp fragments from the crystal structure shows an increasing contribution of dodecamer (abcd)3 and tetramer (abcd) in solution, as a function of pH values (8.0 and 9.0) and temperature. Finally, our data show, for the first time, that oxy-HbRa, in neutral and acidic media, does not undergo oligomeric dissociation before denaturation, while in alkaline media the oligomeric dissociation process is an important step in the thermal denaturation.

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Rhinodrilus alatus is an annelid and its giant extracellular hemoglobin (HbRa) has a molecular mass (MM) of 3500kDa. In the current study, the characterization of MM values of the HbRa subunits, and the effects of surfactants and alkaline pH upon HbRa stability were monitored. Electrophoresis, MALDI-TOF-MS and AUC show that the MM values of HbRa subunits are very close, but not identical to the Glossoscolex paulistus hemoglobin (HbGp). The monomer d is found to exist in, at least, two isoforms: the main one, d1, displays a MM of 16,166±16Da, and the second one, d2, is less intense with MM of 16,490±20Da. For the trimer abc and tetramer abcd, single contributions around 51,470Da and 67,690Da were observed, respectively. Finally, the monomers a, b, and c, present MM values of 17,133, 17,290 and 15,506Da, respectively. Both CTAC and DTAB interact strongly with HbRa, and up to seven surfactant molecules are bound to the protein. On the other hand, spectroscopic studies show that HbRa is more stable at alkaline pH, as compared to HbGp. Thus, our data suggest that alkaline medium, up to pH10.0, induces the oligomeric dissociation, without promoting the subunits unfolding and heme iron oxidation. Our results suggest that the MM of the annelid hemoglobin subunits is conserved to a great extent in the evolution process of these species.

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Hoy en día, las modernas técnicas de producción porcina exigen cada vez más destetes tempranos. Sin embrago, el destete representa una de las etapas más críticas en la vida productiva del cerdo, debido a que durante ella se suman una serie de factores estresantes y cambios fisiológicos. En la presente revisión se analizan los factores más importantes que causan estrés durante esta etapa, como la separación de la cerda, el transporte, el cambio de alimento, el alojamiento en nuevas instalaciones y el agrupamiento con lechones extraños. La interacción de los lechones con estos factores estresantes incrementa el nivel de estrés que representa, per se, la separación de la cerda y el lechón durante el destete, ya que habitualmente originan "retraso en el crecimiento", además de aumento de la susceptibilidad frente a agentes patógenos entéricos causantes de enfermedades. Por ello, los distintos factores que afectan la fisiología, el metabolismo y el comportamiento del lechón deben ser controlados adecuadamente. Se concluye que el conocimiento de la biología de la especie y un entrenamiento adecuado del personal, son necesarios para disminuir los problemas de bienestar del lechón destetado, por lo que, con el fin de evitarlos, se recomiendan algunas prácticas derivadas de los hallazgos presentados.

Nowadays, modern swine production techniques promote early weaning. Weaning constitutes one of the most critical stages in the productive life of swine as it is a phase that entails a whole series of stressful factors and physiological changes. This review examines the most important factors that cause stress during this stage, including: separation from the sow, transport, changes in alimentation, lodging in different installations, and being grouped together with strange piglets. The interaction of young pigs with all these stressor factors exercises a cumulative effect that intensifies the level of stress they experience during separation from the sow during the weaning process itself, an event that frequently results in "delayed growth" accompanied by an increased susceptibility to disease-causing, enteric pathogenic agents. For these reasons, it is important to adequately control the variety of factors that affect the physiology, metabolism and behavior of piglets. The conclusion is that both knowledge of the biology of the species and suitable personnel training are necessary to reduce the problems that arise from these issues related to the welfare of weaned piglets. Finally, this study recommends some practices derived from the findings presented, with a view to improving the welfare of recently weaned piglets.

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Glossoscolex paulistus (HbGp) hemoglobin is an oligomeric protein, presenting a quaternary structure constituted by 144 globin and 36 non-globin chains (named linkers) with a total molecular mass of 3.6 MDa. SDS effects on the oxy-HbGp thermal stability were studied, by DLS and SAXS, at pH 5.0, 7.0 and 9.0. DLS and SAXS data show that the SDS-oxy-HbGp interactions induce a significant decrease of the protein thermal stability, with the formation of larger aggregates, at pH 5.0. At pH 7.0, oxy-HbGp undergoes complete oligomeric dissociation, with increase of temperature, in the presence of SDS. Besides, oxy-HbGp 3.0mg/mL, pH 7.0, in the presence of SDS, has the oligomeric dissociation process reduced as compared to 0.5mg/mL of protein. At pH 9.0, oxy-HbGp starts to dissociate at 20 °C, and the protein is totally dissociated at 50 °C. The thermal dissociation kinetic data show that oxy-HbGp oligomeric dissociation at pH 7.0, in the presence of SDS, is strongly dependent on the protein concentration. At 0.5mg/mL of protein, the oligomeric dissociation is complete and fast at 40 and 42 °C, with kinetic constants of (2.1 ± 0.2) × 10(-4) and (5.5 ± 0.4) × 10(-4) s(-1), respectively, at 0.6 mmol/L SDS. However, at 3.0mg/mL, the oligomeric dissociation process starts at 46 °C, and only partial dissociation, accompanied by aggregates formation is observed. Moreover, our data show, for the first time, that, for 3.0mg/mL of protein, the oligomeric dissociation, denaturation and aggregation phenomena occur simultaneously, in the presence of SDS. Our present results on the surfactant-HbGp interactions and the protein thermal unfolding process correspond to a step forward in the understanding of SDS effects.

Assuntos

RESUMO

The thermal denaturation and aggregation of the HbGp, in the oxy- and cyanomet-forms, was investigated by DSC, AUC, DLS, optical absorption and CD, in the pH range from 5.0 to 7.0. Oxy-HbGp has a denaturation process partially reversible and dependent on the temperature. DSC melting curve is characterized by a single peak with T(c) value of 333.4 ± 0.2K for oxy-HbGp, while two peaks with T(c) values of 332.2 ± 0.1 and 338.4 ± 0.2K are observed for cyanomet-HbGp, at pH 7.0. In acidic pH oxy- and cyanomet-HbGp are more stable showing higher T(c) values and aggregation. AUC data show that, HbGp, at pH 7.0, upon denaturation, remains undissociated at 323 K, presenting oligomeric dissociation at 333 (12 ± 3% of tetramer and 88 ± 5% of whole HbGp) and 343 K (70 ± 5% of monomer and 30 ± 2% of trimer). DLS data show that the lag period before aggregation is dependent on the temperature and HbGp concentration. Optical absorption and CD results show that the increase of temperature leads to the oxy-HbGp oxidation and aggregation, above 331 K, in acidic pH. CD data, for HbGp, present a greater thermal stability in acid medium than at neutral pH, with similar T(c) values for both oxidation forms. Our data are consistent with previous studies and represents an advance in understanding the thermal stability of oligomeric HbGp structure.

Assuntos

RESUMO

The urea effect on the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) stability was studied by analytical ultracentrifugation (AUC) and small angle X-ray scattering (SAXS). AUC data show that the sedimentation coefficient distributions curves c (S), at 1.0 mol/L of urea, display a single peak at 57 S, associated to the undissociated protein. The increase in urea concentration, up to 4.0 mol/L, induces the appearance of smaller species, due to oligomeric dissociation. The sedimentation coefficients and molecular masses are 9.2S and 204 kDa for the dodecamer (abcd)(3), 5.5S and 69 kDa for the tetramer (abcd), 4.1S and 52 kDa for the trimer (abc) and 2.0 S and 17 kDa for the monomer d, respectively. SAXS data show initially a decrease in the I(0) values due to the oligomeric dissociation, and then, above 4.0 mol/L of denaturant, for oxy-HbGp, and above 6.0 mol/L for cyanomet-HbGp, an increase in the maximum dimension and gyration radius is observed, due to the unfolding process. According to AUC and SAXS data the HbGp unfolding is described by two phases: the first one, at low urea concentration, below 4.0 mol/L, characterizes the oligomeric dissociation, while the second one, at higher urea concentration, is associated to the unfolding of dissociated species. Our results are complementary to a recent report based on spectroscopic observations.

Assuntos