DM intake by feedlot beef cattle: factors that impact intake patterns.

DM intake (DMI) for individual pens of cattle is recorded daily or averaged across each week by most commercial feedlots as an index of performance. Numerous factors impact DMI by feedlot cattle. Some are available at the start of the feedlot period (initial BW, sex), and others become available early in the feeding period (daily DMI during adaptation) or more continuously (daily DMI from the previous week). To evaluate the relative impact of these factors on daily DMI during individual weeks within the feedlot period, we employed a dataset compiled from 2009 to 2014 from one commercial feedlot, including 4 132 pens (485 458 cattle), which were split into two fractions: 80% were used to calculate DMI regressions on these factors to develop a prediction equation for mean DMI for each week of the feeding period, and 20% were reserved to test the adequacy of these prediction equations. Correlations were used to determine the relationship between all available variables with observed DMI. These variables were then included in the generalized least squares regression models. A veracity test of the model was performed against the reserved data. Daily DMI from previous week was the factor most highly correlated with daily DMI (P < 0.10) during from week 6 to week 31, accounting for approximately 70% of the variation, followed by mean daily DMI during adaptation period (weeks 1-4), including in the prediction model from weeks 5 to 12. Initial shrunk BW (ISBW) was the third most correlated factor, which was included in prediction equations from week 5 to week 20. Sex entered the prediction model only after week 8. Daily DMI for each test week within the feeding period was predicted closely (r2 = 0.98) by these four factors (RMSE = 0.155 kg). In conclusion, the mean daily DMI during each week of the finishing period for a pen of cattle could be predicted closely based on mean daily DMI intake during the previous week plus other variables available early in a feedlot period (daily DMI during adaptation period, ISBW and sex).

Feedlot performance and rumen morphometrics of Nellore cattle adapted to high-concentrate diets over periods of 6, 9, 14 and 21 days.

The energy content of finishing diets offered to feedlot cattle may vary across countries. We assumed that the lower is the energy content of the finishing diet, the shorter can be the adaptation period to high-concentrate diets without negatively impacting rumen health while still improving feedlot performance. This study was designed to determine the effects of adaptation periods of 6, 9, 14 and 21 days on feedlot performance, feeding behaviour, blood gas profile, carcass characteristics and rumen morphometrics of Nellore cattle. The experiment was designed as a completely randomised block, replicated 6 times, in which 96 20-month-old yearling Nellore bulls (391.1 ± 30.9 kg) were fed in 24 pens (4 animals/pen) according to the adaptation period adopted: 6, 9, 14 or 21 days. The adaptation diets contained 70%, 75% and 80.5% concentrate, and the finishing diet contained 86% concentrate. After adaptation, one animal per pen was slaughtered (n = 24) for rumen morphometric evaluations and the remaining 72 animals were harvested after 88 days on feed. Orthogonal contrasts were used to assess linear, quadratic and cubic relationships between days of adaptation and the dependent variable. Overall, as days of adaptation increased, final BW (P = 0.06), average daily gain (ADG) (P = 0.07), hot carcass weight (P = 0.04) and gain to feed ratio (G : F) (P = 0.07) were affected quadratically, in which yearling bulls adapted by 14 days presented greater final BW, ADG, hot carcass weight and improved G : F. No significant (P > 0.10) days of adaptation effect was observed for any of feeding behaviour variables. As days of adaptation increased, the absorptive surface area of the rumen was affected cubically, where yearling bulls adapted by 14 days presented greater absorptive surface area (P = 0.03). Thus, Nellore yearling bulls should be adapted by 14 days because it led to improved feedlot performance and greater development of rumen epithelium without increasing rumenitis scores.

Synthesis, structure-activity relationship and trypanocidal activity of pyrazole-imidazoline and new pyrazole-tetrahydropyrimidine hybrids as promising chemotherapeutic agents for Chagas disease.

Drug therapy for Chagas disease remains a major challenge as potential candidate drugs have failed clinical trials. Currently available drugs have limited efficacy and induce serious side effects. Thus, the discovery of new drugs is urgently needed in the fight against Chagas' disease. Here, we synthesized and evaluated the biological effect of pyrazole-imidazoline (1a-i) and pyrazole-tetrahydropyrimidine (2a-i) derivatives against relevant clinical forms of Trypanosoma cruzi. The structure-activity relationship (SAR), drug-target search, physicochemical and ADMET properties of the major active compounds in vitro were also assessed in silico. Pyrazole derivatives showed no toxicity in Vero cells and also no cardiotoxicity. Phenotypic screening revealed two dichlorinated pyrazole-imidazoline derivatives (1c and 1d) with trypanocidal activity higher than that of benznidazole (Bz) against trypomastigotes; these were also the most potent compounds against intracellular amastigotes. Replacement of imidazoline with tetrahydropyrimidine in the pyrazole compounds completely abolished the trypanocidal activity of series 2(a-i) derivatives. The physicochemical and ADMET properties of the compounds predicted good permeability, good oral bioavailability, no toxicity and mutagenicity of 1c and 1d. Pyrazole nucleus had high frequency hits for cruzipain in drug-target search and structure activity relationship (SAR) analysis of pyrazole-imidazoline derivatives revealed enhanced activity when chlorine atom was inserted in meta-positions of the benzene ring. Additionally, we found evidence that both compounds (1c and 1d) have the potential to interact non-covalently with the active site of cruzipain and also inhibit the cysteine proteinase activity of T. cruzi. Collectively, the data presented here reveal pyrazole derivatives with promise for further optimization in the therapy of Chagas disease.

Biomass smoke COPD has less tomographic abnormalities but worse hypoxemia compared with tobacco COPD.

Special attention has emerged towards biomass smoke-induced chronic obstructive pulmonary disease (COPD), providing new knowledge for prevention and therapeutic approach of non-smoker COPD patients. However, the understanding of biomass smoke COPD is still limited and somewhat controversial. The aim of the present study was to compare COPD exclusively caused by tobacco smoking with COPD exclusively caused by environmental or occupational exposures. For this cross-sectional study, COPD patients were recruited from outpatient clinics and formed two groups: non-smoker COPD group (n=16) with exposure to biomass smoke who did not smoke cigarette and tobacco smoker COPD group (n=15) with people who did not report biomass smoke exposure. Subjects underwent pulmonary function tests, thoracic high-resolution computed tomography, 6-min walk test, and sputum induction. The non-smoker COPD group had biomass smoke exposure of 133.3±86 hour-years. The tobacco COPD group smoked 48.5±27.4 pack-years. Women were 62.5 and 66.7%, respectively, of non-smokers and smokers. The non-smoker COPD group showed higher prevalence of dyspnea, lower arterial oxygen tension (PaO2), and lower arterial oxygen saturation (SaO2%) with similar spirometry results, lung volumes, and diffusion capacity. Regarding inflammatory biomarkers, differences were detected in sputum number of lymphomononuclear cells and in sputum concentrations of interleukin (IL)-6 and IL-8 with higher values in the smoker group. Emphysema was more prevalent in the tobacco smoker group, which also showed higher relative bronchial wall thickness and lower lung density by quantitative analysis. Biomass smoke induced more hypoxemia compared to tobacco in COPD patients with similar severity.

Nanobiostructure of fibrous-like alumina functionalized with an analog of the BP100 peptide: Synthesis, characterization and biological applications.

The functionalization of alumina nanoparticles of specific morphology with antimicrobial peptides (AMP) can be a promising strategy for modeling medical devices and packaging materials for cosmetics, medicines or food, since the contamination by pathogens could be reduced. In this paper, we show the synthesis of a fibrous-like alumina nanobiostructure, as well as its functionalization with the peptide EAAA-BP100, an analog of the antimicrobial peptide BP100. The antibacterial activity of the obtained material against some bacterial strains is also investigated. The covalent binding of the peptide to the nanoparticles was promoted by a reaction between the carboxyl group of the glutamate side chain (E1) of the peptide and the amino groups of the alumina nanoparticles, previously modified by reaction with 3-aminopropyltrietoxysilane (APTES). The functionalized nanoparticles were characterized by zeta potential measurements, Fourier transform infrared spectroscopy, and other physicochemical techniques. Although the obtained alumina nanobiostructure shows a relatively low degree of substitution with EAAA-BP100, antibacterial activities against Escherichia coli and Salmonella typhimurium strains are appreciably higher than the activities of the free peptide. The obtained results can affect the design of new hybrid nanobiomaterials based on nanoparticles functionalized with AMP.

Efficacy of 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinone derivatives against different Trypanosoma cruzi discrete type units: Identification of a promising hit compound.

The limited efficacy of benznidazole (Bz) indicated by failures of current Phase II clinical trials emphasizes the urgent need to identify new drugs with improved safety and efficacy for treatment of Chagas disease (CD). Herein, we analyzed the efficacy of a series of 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones against different Trypanosoma cruzi discrete type units (DTUs) of relevant clinical forms of CD. Cytotoxic and trypanocidal effect of naphthoquinone derivatives were assessed in mammalian cells, trypomastigotes and intracellular amastigotes using, luminescent assays (CellTiter-Glo and T. cruzi Dm28c-luciferase) and/or counting with a light microscope. Reactive oxygen species (ROS) production and intracellular targets of promising compounds were assessed with 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) probe and ultrastructural analysis, respectively. ADMET properties were analyzed by in silico modeling. Most of the compounds showed low cytotoxic effect. Only two compounds (Compounds 2 and 11) had IC50 values lower than Bz, showing higher susceptibility of bloodstream trypomastigotes. Compound 2 exhibited greater efficacy against trypomastigotes from different T. cruzi DTUs, even better than Bz against Brazil and CL strains. Ultrastructural analysis revealed changes in intracellular compartments, suggesting autophagy as one possible mechanism of action. Oxidative stress, induced by Compound 2, resulted in elevated level of ROS, leading to parasite death. Compound 2 was also effective against intracellular amastigotes, showing high selectivity index. ADMET analysis predicted good oral bioavailability, reduced drug metabolism and no carcinogenic potential for Compound 2. The data highlight Compound 2 as a hit compound and stimulate further structural and pharmacological optimization to potentiate its trypanocidal activity and selectivity.

Physical performance, quality of life and sexual satisfaction evaluation in adults with cystic fibrosis: An unexplored correlation.

OBJECTIVE: Quality of life (QOL), sexual satisfaction (SS) and physical performance have been assessed in the management of numerous chronic diseases. METHODS: In this study, the following tests and surveys were applied: (i) QOL questionnaire [Cystic Fibrosis Questionnaire (CFQ)]; (ii) SS questionnaire (SSQ) [female sexual quotient (FSQ) and male sexual quotient (MSQ)]; (iii) 6-minute walk test (6MWT). Spearman's correlation was used for comparison between the data; the Mann-Whitney test was applied to analyze the difference between genders. A total of 52 adult patients with CF were included in this study. RESULTS: There was a positive correlation between CFQ domains and SSQ questions. The CFQ showed a positive correlation with peripheral oxygen saturation of hemoglobin (SpO2) and the distance walked in the 6MWT, and a negative correlation with the Borg scale. The SSQ showed positive correlation with the distance walked and a negative correlation with the Borg scale. For some markers evaluated in the 6MWT, there was sometimes association with the evaluated domains and questions. Male patients showed better scores in the emotional CFQ domain, better performance in SSQ and physical performance. CONCLUSIONS: There was a correlation between CFQ, SSQ and 6MWT in CF. Finally; we believe that QOL surveys should assess the domain "sexuality" as well as physical performance tests.

Relationships of feedlot performance, feeding behavior, rumen morphometrics, and carcass characteristics of Nellore cattle differing in phenotypic residual feed intake.

The objective of this study was to examine the relationship of DMI fluctuation, feedlot performance, feeding behavior, rumen morphometrics, and carcass characteristics in Nellore cattle classified by residual feed intake (RFI). One experiment was conducted in 2 consecutive years using individual pens (1.0 × 7.0 m) at the São Paulo State University feedlot, Dracena campus, Brazil. The experiment in year 1 started in June of 2012 with forty-eight 20-mo-old Nellore yearling bulls with an initial BW of 358.2 ± 19.4 kg. The experiment in year 2 started in January of 2013 with sixty 20-mo-old Nellore yearling bulls with an initial BW of 402.5 ± 33.0 kg. Experiments in years 1 and 2 lasted 94 and 84 d, respectively. All yearling bulls were categorized as high RFI (>0.5 SD above the mean, = 25), medium RFI (±0.5 SD from the mean, = 56), and low RFI (<0.5 SD below the mean, = 27). Visual appraisal to collect behavior data was made on d 40 (finishing period) of both years. Yearling bulls were harvested when average across treatment groups achieved a fat thickness of 4 mm at the 12th rib. Low-RFI yearling bulls had lower daily DMI, expressed either in kilograms ( < 0.01) or as percentage of BW ( < 0.01), and improved G:F ( < 0.01) when compared to high-RFI animals. No differences were observed ( > 0.10) for ADG, final BW, or HCW among RFI groups. Also, low-RFI yearling bulls had thinner final 12th rib ( < 0.01) and biceps femoris (P8) fat thickness ( < 0.01). Low-RFI yearling bulls were slower to consume ( = 0.03) and ruminate ( < 0.01) 1 kg of either DM or NDF. No significant ( > 0.10) RFI effect was observed for any ruminal morphometrics variables evaluated, with the exception of papillae area, in which low-RFI Nellore yearling bulls tended to have smaller ( = 0.07) papillae area than medium-RFI animals. In general, low-RFI Nellore yearling bulls consumed more particles larger than 19 and 8 mm and had a similar performance when compared to both medium- and high-RFI bulls; however, carcass fat composition was negatively impacted.

Markers of pregnancy: how early can we detect pregnancies in cattle usingpregnancy-associated glycoproteins (PAGs) and microRNAs?

Pregnancy detection has evolved over the last few decades and the importance of early pregnancy detection is critical to minimize the amount of time a cow spends not pregnant. Embryonic mortality (EM) is generally considered to be the primary factor limiting pregnancy rates in cattle and occurs early (

Efeito do tamanho da leitegada sobre a variação dos pesos ao nascer e ao desmame em leitões da raça Landrace / Effect of litter size on the variation in birth and weaning weights of Landrace piglets

Objetivou-se avaliar o efeito da classe de tamanho de leitegada ao nascer sobre a variação do peso ao nascer e ao desmame e sobre a taxa de sobrevivência dos leitões do nascimento ao desmame. Para isso usou-se informações de peso individual ao nascer e ao desmame de leitões de um banco de dados de 295 leitegadas de suínos da raça Landrace, nascidos entre 2000 e 2010, em uma granja de suínos do oeste do estado do Paraná. As leitegadas foram classificadas pelo número total de leitões nascidos em pequenas (até 7 leitões), médias (8 a 13 leitões) e grandes (14 e mais leitões). Os dados foram analisados considerando-se os efeitos de ano de acasalamento das porcas e classe de tamanho de leitegada ao nascer. Correlações entre as características de peso médio e variância do peso e tamanho da leitegada foram maiores nas leitegadas médias e grandes. Classe de tamanho da leitegada influenciou significativamente peso médio ao nascer e ao desmame dos leitões e variância do peso ao nascer. Leitões de leitegadas médias e grandes pesaram menos, apresentaram maior variação do peso ao nascer e menor taxa de sobrevivência até o desmame do que leitões de leitegadas pequenas...

The objective of this study was to evaluate the effect of the size class of the litter at birth on the variation in birth and weaning weights and on the survival rate of piglets from birth to weaning. For this purpose, records of individual weight at birth and weaning of piglets obtained from a database of 295 Landrace litters born between 2000 and 2010 on a pig farm in the western region of the State of Paraná were used. The litters were classified as small (up to 7 piglets), medium (8 to 13 piglets), and large (> 14 piglets) according to the total number of piglets born. The data were analyzed considering the effects of the year of sow mating and size class of the litter at birth. The correlations between mean weight and variance in litter weight and size were higher for medium and large litters. The size class of the litter significantly influenced the mean weight of piglets at birth and weaning and the variance in birth weight. Piglets born in medium and large litters weighed less and exhibited greater birth weight variation and a lower survival rate until weaning than piglets born in small litters...

Efeito do tamanho da leitegada sobre a variação dos pesos ao nascer e ao desmame em leitões da raça Landrace / Effect of litter size on the variation in birth and weaning weights of Landrace piglets

Objetivou-se avaliar o efeito da classe de tamanho de leitegada ao nascer sobre a variação do peso ao nascer e ao desmame e sobre a taxa de sobrevivência dos leitões do nascimento ao desmame. Para isso usou-se informações de peso individual ao nascer e ao desmame de leitões de um banco de dados de 295 leitegadas de suínos da raça Landrace, nascidos entre 2000 e 2010, em uma granja de suínos do oeste do estado do Paraná. As leitegadas foram classificadas pelo número total de leitões nascidos em pequenas (até 7 leitões), médias (8 a 13 leitões) e grandes (14 e mais leitões). Os dados foram analisados considerando-se os efeitos de ano de acasalamento das porcas e classe de tamanho de leitegada ao nascer. Correlações entre as características de peso médio e variância do peso e tamanho da leitegada foram maiores nas leitegadas médias e grandes. Classe de tamanho da leitegada influenciou significativamente peso médio ao nascer e ao desmame dos leitões e variância do peso ao nascer. Leitões de leitegadas médias e grandes pesaram menos, apresentaram maior variação do peso ao nascer e menor taxa de sobrevivência até o desmame do que leitões de leitegadas pequenas...(AU)

The objective of this study was to evaluate the effect of the size class of the litter at birth on the variation in birth and weaning weights and on the survival rate of piglets from birth to weaning. For this purpose, records of individual weight at birth and weaning of piglets obtained from a database of 295 Landrace litters born between 2000 and 2010 on a pig farm in the western region of the State of Paraná were used. The litters were classified as small (up to 7 piglets), medium (8 to 13 piglets), and large (> 14 piglets) according to the total number of piglets born. The data were analyzed considering the effects of the year of sow mating and size class of the litter at birth. The correlations between mean weight and variance in litter weight and size were higher for medium and large litters. The size class of the litter significantly influenced the mean weight of piglets at birth and weaning and the variance in birth weight. Piglets born in medium and large litters weighed less and exhibited greater birth weight variation and a lower survival rate until weaning than piglets born in small litters...(AU)

An effective approach for modifying carbonaceous materials with niobium single sites to improve their catalytic properties.

In this paper we show a very simple route for the incorporation of catalytically active niobium species on the surface of carbon materials, such as graphene oxide, carbon nanotubes and activated carbon. Some existing methods of incorporating a transition metal on a support have involved co-precipitation or wet impregnation, to obtain the corresponding oxides. These methods, however, cause reduction in the specific area of the support and can also form large metal oxide particles with loss of metal exposure. Therefore, here we present a novel way to add catalytically active species on the surfaces of different types of carbon through the formation of interaction complexes between the metal precursor and the functional groups of the carbon matrix. Because of the excellent catalytic properties exhibited by the niobium species we choose the NH4[NbO(C2O4)2(H2O)2]·2H2O salt as the model precursor. The characterization by XPS reveals the presence of the niobium species indicated by the displacement of the peaks between 206-212 eV related to the oxalate species according to the spectrum from pure niobium oxalate. Images obtained by TEM and SEM show the typical morphologies of carbonaceous materials without the niobium oxide formation signal, which indicates the presence of niobium complexes as isolated sites on the carbon surfaces. This new class of materials exhibited excellent properties as catalysts for pollutant oxidation. The presence of Nb promotes the catalytic activation of H2O2 generating hydroxyl radicals in situ, which allows their use in the organic compound oxidation processes. Tests for DBT oxidation indicate that Nb significantly improves the removal of such pollutants in biphasic reactions with removal around 90% under the tested conditions. Theoretical calculations showed that the most favorable adsorption model is an ionic complex presenting a ΔG = -108.7 kcal mol(-1) for the whole adsorption process.

Testis Morphology and Dichotomic Spermatogenesis in the Sugarcane Borer Diatraea saccharalis (F.) (Lepidoptera: Crambidae).

In the present study, we describe the testis morphology and spermatogenesis of the sugarcane borer, one of the most destructive pests of sugarcane, using light, transmission, and scanning electron microscopies. Diatraea saccharalis (F.) larvae have paired, kidney-shaped testes that are limited externally and divided into four follicles by tunica cells. The adults have two fused whitish and spherical testes that are divided into eight follicles and are composed of spermatogonia, spermatocyte, spermatid, and sperm bundles. The spermatogonia and spermatocyte cysts are located at the apical extremity of the follicle, while the spermatid cysts and sperm bundles are located at the basal extremity of the follicle. Inside of the cysts, which are formed by the somatic cells, the germ line cells develop synchronously and are interconnected by cytoplasmic bridges. Each cyst contains only apyrene or eupyrene, and none of the cysts contain both of the cells. The inner part of the apyrene cyst consists of an electron-dense cap as opposed to a nucleus. The eupyrene sperm contains a nucleus, acrosome, and reticular and lacinate appendages. Both of the sperm types have a "9 + 9 + 2" axoneme and two mitochondrial derivatives at the tail region. The spermatogenesis process and spermatozoa morphology are similar to that of other Lepidoptera.

De pais para filhos: modos intencionais de transmitir valores / From parents to children: intentional manners of transmiting values

Investigaram-se estratégias utilizadas por pais para transmitir valores aos filhos. Assistir a um filmeinfantil e simular sua recontação à criança foi o procedimento usado para introduzir nessa temáticadez pais/mães, com filho de 6 a 9 anos. Eles participaram de entrevista semiestruturada cujas respostasforam analisadas qualitativamente, revelando diferentes estratégias intencionais para transmitirvalores: instruir ativamente o filho; aproveitar notória motivação da criança e lhe agregar valor; eensinar pela experiência (ou privação dela) proporcionada ao filho. A recontação revelou-se umprocedimento adequado de pesquisa, pois os entrevistados realçaram ou minimizaram trechos doenredo para transmitir valores aos filhos ou comentaram que assim o fariam. Destaca-se o potencial dese explorar a temática sob o foco dos estudos intergeracionais(AU)

Evaluation of productivity of sexually precocious Nelore heifers.

The objectives of the present study were to investigate the influence of yearling weight on the occurrence of early pregnancy and to determine differences between precocious and non-precocious heifers in terms of pre- and postnatal calf mortality, calf weight and height, mature cow weight, and stayability of the cow in the herd. Data from 26 977 females of a Nelore herd that participated in the breeding season between 1986 and 2004 were analyzed. The influence of yearling weight on sexual precocity and differences between precocious and non-precocious heifers in pre- and postnatal calf mortality and stayability were analyzed using the GENMOD procedure of the SAS program. Differences in the growth traits between precocious and non-precocious animals were estimated by contrast analysis. Three groups were analyzed for postnatal mortality: first calving of the heifers, calves born from the third calving and all offspring of the cow. In order to have a standardized calving to conception period for all females (precocious and non-precocious), calves born from the second calving were not included in the analysis. This was necessary because the first calving to conception period (days open) of precocious heifers was longer than for non-precocious due to farm reproductive management. No differences in postnatal mortality rates, from the third calving, were observed between the two groups of heifers studied. Analysis of all offspring of the dams showed a 9% higher probability of death of calves born to precocious heifers compared with calves born to non-precocious heifers. With respect to stayability, precocious heifers presented 33% greater odds to remain in the herd until 5 and 6 years of age and 28% greater odds to remain in the herd until 7 years when compared with non-precocious heifers. Precocious heifers weaned calves (205 days) significantly heavier than non-precocious ones, 1.410 and 0.797 kg considering the weaning weights of all offspring and of the third calving, respectively. With respect to sexual precocity, the results suggest that the probability of heifers to become pregnant at 16 months of age increases with increasing weight. However, heifers weighing more than 240 kg present practically the same pregnancy probability. Nevertheless, exposure of heifers during the early breeding season is recommended for beef cattle herds raised in tropical regions in view of the numerous benefits demonstrated here.

Fourier transform infrared photoacoustic spectroscopy as a potential tool in assessing the role of diet in cuticular chemical composition of Ectatomma brunneum.

The cuticular chemical composition plays a significant role in the recognition of nest mates in social insects, thus functioning as a chemical signature of the colony. The structure of cuticular chemicals is subject to interference from genetic and exogenous factors, including diet. In this study, various colonies of the Ectatomma brunneum ant were removed from their natural environment and housed in a laboratory to monitor the response of the cuticular chemical composition to dietary changes. Analyses were performed using gas chromatography and Fourier transform infrared photoacoustic spectroscopy, which has not been previously used for this type of analysis. The results indicate that this method is useful for analyzing biological and natural systems. We observed changes in the chemical signature with food traces in the first 30 days under feed control. Therefore, genetic information may not be the only criterion that can be used to describe the chemical signature of a species; environmental variations also influence recognition signals. Furthermore, these results reinforce the reliability of the Fourier transform infrared photoacoustic spectroscopy method.

Synthesis and characterization of zinc oxide nanocrystals and histologic evaluation of their biocompatibility by means of intraosseous implants.

AIM: To synthesize and characterize zinc oxide (ZnO) nanocrystals and assess their biological properties for applications in dentistry, particularly in endodontics, by means of intraosseous implants. METHODOLOGY: ZnO nanocrystals were synthesized and characterized by micro-Raman spectroscopy and X-ray Diffraction. Ten guinea pigs were divided into two groups representing experimental periods of 4 and 12 weeks and received implants on both sides of the mandible in the region of the symphysis. The connective tissue response along the lateral wall outside the cup served as the negative control. The animals were euthanized at the end of each observation period and prepared for routine histological examinations which evaluated inflammatory response and material biocompatibility. RESULTS: ZnO nanocrystals were highly pure, crystalline, and averaged 21 nm in size. After 12 weeks, tissue analysis revealed the presence of a thin layer of connective tissue with some giant cells between the implanted material and underlying bone tissue. While signs of mild inflammation could be seen, bone resorption and remodeling were not apparent. CONCLUSION: ZnO nanocrystals were biocompatible, well tolerated and allowed new bone formation and bone remodelling.

Comparison of the lactate minimum speed and the maximal lactate steady state to determine aerobic capacity in purebred Arabian horses.

AIM: To compare five different protocols for estimating the lactate minimum speed (LMS) with that for estimating the maximal lactate steady state (MLSS) in Arabian horses, in order to obtain a more rapid method for monitoring aerobic capacity and prescribing training schedules. METHODS: Eight purebred Arabian horses were conditioned to exercise on a treadmill for 12 days then submitted to three to five exercise sessions to determine the MLSS. Blood samples were collected from a jugular catheter at specific intervals for measurement of lactate concentrations. The MLSS was the velocity maintained during the last 20 minutes of constant submaximal exercise, at which the concentration of lactate increased by no more than 1.0 mmol/L. The LMS test protocols (P1 - P5) included a warm-up period followed by a high-intensity gallop. The speed was then reduced to 4 m/s, and the incremental portion of the test was initiated. In P1, P2, and P3, the velocity increment was 0.5 m/s, and the duration of each incremental stage was three, five and seven minutes, respectively. In P4 and P5, the velocity increments were 1.0 and 1.5 m/s, respectively, and the duration of the stages was fixed at five minutes each. A second-degree polynomial function was fitted to the lactate-velocity curve, and the velocity corresponding to the lowest concentration of lactate was the LMS. RESULTS: Only the mean LMS determined by P1 and P2 did not differ from the velocity determined by the MLSS test (p > 0.1). There was a strong correlation (r >0.6) between P1 and the MLSS velocity. A limits of agreement plot revealed that the best agreement occurred between the MLSS test and P1 (mean bias = 0.14 m/s), followed by P2 (bias = -0.22 m/s). The lactate concentrations associated with the various LMS protocols did not differ. CONCLUSIONS: This study shows the variation between protocols of the LMS test for determining the onset of blood lactate accumulation but also reveals that, at least for Arabian horses, the P1 protocol of the LMS has good agreement with the MLSS.

Trypanosoma cruzi heparin-binding proteins present a flagellar membrane localization and serine proteinase activity.

Heparin-binding proteins (HBPs) play a key role in Trypanosoma cruzi-host cell interactions. HBPs recognize heparan sulfate (HS) at the host cell surface and are able to induce the cytoadherence and invasion of this parasite. Herein, we analysed the biochemical properties of the HBPs and also evaluated the expression and subcellular localization of HBPs in T. cruzi trypomastigotes. A flow cytometry analysis revealed that HBPs are highly expressed at the surface of trypomastigotes, and their peculiar localization mainly at the flagellar membrane, which is known as an important signalling domain, may enhance their binding to HS and elicit the parasite invasion. The plasmon surface resonance results demonstrated the stability of HBPs and their affinity to HS and heparin. Additionally, gelatinolytic activities of 70 kDa, 65·8 kDa and 59 kDa HBPs over a broad pH range (5·5-8·0) were revealed using a zymography assay. These proteolytic activities were sensitive to serine proteinase inhibitors, such as aprotinin and phenylmethylsulfonyl fluoride, suggesting that HBPs have the properties of trypsin-like proteinases.

Fitodefensivos em plantas medicinais: macromoléculas hidrofílicas de folhas de mil folhas (Achillea millefolium L. ) inibem o crescimento in vitro de bactérias fitopatogênicas / Agrochemicals in medicinal plants: hydrophilic macromolecules from leaves of "mil folhas" (Achillea millefolium L. ) inhibit in vitro growth of phytopathogenic bacteria

Extratos aquosos da planta medicinal Achillea millefolium contêm macromoléculas de interesse para desenvolver fitodefensivos para a agricultura. Duas frações de mil folhas foram obtidas por ultrafiltração, E1 (contendo moléculas maiores que 30 kDa), e E3 (peptídeos entre 1 e 10 kDa) que inibiram o crescimento das bactérias fitopatogênicas Ralstonia solanacearum, gram-negativa, e Clavibacter michiganensis subsp. michiganensis, gram-positiva, com dependência de concentração. Os valores de concentração inibitória mínima (CIM) para ambos os extratos e bactérias foram baixos, entre 20 e 80µM. A CIM relativa à proteína total evidenciou a presença de macromoléculas muito ativas em E3, embora com baixa concentração proteica. E3 se aplica à prospecção de peptídeos antimicrobianos. Estimar a CIM relativa à quantidade de amostra vegetal valorizou o potencial antimicrobiano natural de E1, que contém alta concentração proteica. E1e E3 se aplicam ao desenvolvimento de fitodefensivos para uso biotecnológico. A ultrafiltração fracionou as amostras de forma nativa, rápida, e com baixo custo; além de dessalinizar, clarificar, purificar, e concentrar E1 e E3. Esse estudo inédito sobre a separômica e a ação antimicrobiana de extratos macromoleculares aquosos de mil folhas sugere que plantas cicatrizantes podem apresentar grande potencial para desenvolver fitodefensivos agrícolas naturais não danosos, à semelhança de medicamentos fitoterápicos.

Aqueous extracts from the medicinal plant Achillea millefolium contain macromolecules of interest to develop agrochemicals for agriculture. Two fractions of "mil folhas" were obtained by ultrafiltration, E1 (containing molecules larger than 30 kDa) and E3 (peptides between 1 and 10 kDa), which inhibited the growth of phytopathogenic bacteria Ralstonia solanacearum, gram-negative, and Clavibacter michiganensis subsp. michiganensis, gram-positive, concentration-dependent. The values of minimum inhibitory concentration (MIC) for both extracts and both bacteria were low, ranging from 20 to 80µM. The MIC relative to total protein evidenced the presence of very active macromolecules in E3, although showing low protein concentration. E3 applies to the prospection of antimicrobial peptides. The estimated MIC relative to the amount of plant sample valued the natural antimicrobial potential of E1, which contains high protein concentration. E1 and E3 can be used in the development of agrochemicals for biotechnological purposes. The ultrafiltration procedure fractionated the samples in a rapid and native way and at a low cost; it also desalted, clarified, concentrated and purified both E1 and E3. This pioneering study on the separomics and on the antimicrobial activity of macromolecular aqueous extracts from "mil folhas" suggests that healing plants have great potential to develop non-harmful agricultural natural agrochemicals, similarly to the available phytotherapic drugs.