Enzymatic activity of bone markers on Lithobates catesbeianus (Shaw, 1802) growth during the ossification process / Atividade enzimática de marcadores ósseos no crescimento de Lithobates catesbeianus (Shaw, 1802) durante o processo de ossificação

Abstract In order to better understand the ossification processes in anurans our study was carried out on tadpoles and adults of Lithobates catesbeianus. In this sense, we characterized the kinetic properties of alkaline phosphatase with p-nitrophenylphosphatase (pNPP) and pyrophosphate (PPi) and evaluated the activities of tartrate-resistant acid phosphatase and acid phosphatase. The enzyme extracts were obtained from tadpoles and adult femurs, which were divided into epiphysis and diaphysis. After homogenization, the samples were submitted to differential centrifugation to obtain cell membranes and, further, to phospholipase C (PIPLC) treatment, to remove membrane-bound proteins anchored by phosphatidylinositol. The average of specific activity for pNPP hydrolysis (at pH 10.5) by alkaline phosphatase released by phosphatidylinositol-specific phospholipase C (PIPLC) from Bacillus cereus among different bone regions at different animal ages was 1,142.57 U.mg-1, while for PPi hydrolysis (at pH 8.0), it was 1,433.82 U.mg-1. Among the compounds tested for enzymatic activity, the one that influenced the most was EDTA, with approximately 67% of inhibition for pNPPase activity and 77% for PPase activity. In the case of kinetic parameters, the enzyme showed a "Michaelian" behavior for pNPP and PPi hydrolysis. The Km value was around 0.6mM for pNPPase activity and ranged from 0.01 to 0.11mM for PPase activity, indicating that the enzyme has a higher affinity for this substrate. The study of pNPP and PPi hydrolysis by the enzyme revealed that the optimum pH of actuation for pNPP was 10.5, while for PPi, which is considered the true substrate of alkaline phosphatase, was 8.0, close to the physiological value. The results show that regardless of the ossification type that occurs, the same enzyme or isoenzymes act on the different bone regions and different life stages of anurans. The similarity of the results of studies with other vertebrates shows that anurans can be considered excellent animal models for the study of biological calcification.

Resumo Para melhor compreender o processo de ossificação em anuros, nosso estudo foi conduzido em girinos e adultos de Lithobates catesbeianus. Nesse sentido, as propriedades cinéticas da fosfatase alcalina com p-nitrofenilfosfato (pNPP) e pirofosfato (PPi) foram caracterizadas, e as atividades enzimáticas das fosfatases ácida e ácida tartarato resistente foram avaliadas. Os extratos enzimáticos foram obtidos de fêmur de girinos e adultos, divididos em epífise e diáfise. Após a homogeneização as amostras foram submetidas à centrifugação diferencial para obter membrana celular e, em seguida, ao tratamento com fosfolipase C (PIPLC), para remover as proteínas de membrana ancoradas por fosfatidilinositol. A média da atividade específica da fosfatase alcalina, liberada pela PIPLC de Bacillus cereus, para a hidrólise de pNPP (pH 10,5) nas diferentes regiões do fêmur e idades dos animais foi de 1.142,57 U.mg-1, enquanto para a hidrólise do PPi (pH 8,0) foi de 1.433,82 U.mg-1. Entre os compostos testados para a atividade enzimática, o de maior influência foi o EDTA, inibindo aproximadamente 67% e 77% das atividades de pNPPase e PPase, respectivamente. Quanto aos parâmetros cinéticos, a enzima apresentou comportamento Michaeliano para a hidrólise dos dois substratos. O valor de Km foi de 0,6 mM para a atividade de pNPPase e variou de 0,01 a 0,11 para a atividade de PPase, indicando uma maior afinidade por esse substrato. O estudo da hidrólise de pNPP e PPi revelou que o pH ótimo aparente de atuação foi de 10,5 para o pNPP e 8,0 para o PPi, próximo ao fisiológico, sendo que esse é considerado o substrato natural da fosfatase alcalina. Os resultados demonstram que, apesar do tipo de ossificação que ocorre, a mesma enzima ou isoenzimas, atuam nos diferentes locais do osso e estágios de vida dos anuros. A similaridade dos estudos com os realizados com outros vertebrados apontam que os anuros podem ser considerados excelentes modelos animais para o estudo da calcificação biológica.

The Influence of Morphological Characteristics on the Ball Throwing Velocity in the Professional Handball Players / Influencia de las Características Morfológicas en la Velocidad de Lanzamiento del Balón en los Jugadores Profesionales de Balonmano

SUMMARY: The aim of this study was to determine influence of upper limbs on the ball throwing velocity. A total of 10 professional handball players (25.74±4.84 years) participated in this study. All of them were playing in the top Montenegrin professional handball league. The results obtained in this study shows that upper limbs have high influence on ball throwing velocity. This study provides normative data and performance standards for professional handball. Coaches can use this information to determine the type of anthropometric characteristics that are needed for handball. Anthropometric parameters such as arm length, wrist diameter, hand length and arm span are the most relevant aspects related to ball throwing speed, given that these parameters cannot be changed through training, they should be taken into account when discovering talents.

El objetivo de este estudio fue determinar la influencia de los miembros superiores sobre la velocidad de lanzamiento de la pelota. En el estudio participaron un total de 10 jugadores profesionales de balonmano (25,74±4,84 años). Todos ellos jugaban en la principal liga profesional de balonmano de Montenegro. Los resultados obtenidos mostraron que los miembros superiores tienen una alta influencia en la velocidad de lanzamiento de la pelota. Este estudio proporciona datos normativos y estándares de rendimiento para el balonmano profesional. Los entrenadores pueden utilizar esta información para determinar el tipo de características antropométricas necesarias para el balonmano. Los parámetros antropométricos como la longitud del brazo, el diámetro de la muñeca, la longitud de la mano y la envergadura del brazo son los aspectos más relevantes relacionados con la velocidad de lanzamiento de la pelota, dado que estos parámetros no se pueden cambiar mediante el entrenamiento, deben tenerse en consideración a la hora de descubrir talentos.

Analysis of drying kinetic of brewer ́s spent grains: effect of the temperature on the physical properties and the content of bioactive compounds / Análisis de la cinética de secado del bagazo residual de malta: efecto de la temperatura sobre las propiedades físicas y el contenido de compuestos bioactivos

Background: Brewer ́s spent grain (BSG) is a biomass by-product generated in large volumes during industrial beer production. BSG has become a growing environmental problem, as most breweries discard it inappropriately, negatively impacting the environment. Alternatives for the exploitation of this by-product have consisted of elaborating food supplements for farm animals, obtaining biofuels, developing adsorbents, and obtaining substances for the food industry. However, the high moisture content in BSG (approximately 70%), poses a significant challenge in exploring various reuse alternatives. Therefore, the implementation of a pre-drying process becomes essential. Objective: This study aimed to analyze the BSG drying kinetics at different temperatures and the effect of the drying temperature on the physical properties and the content of bioactive compounds. Methods: BSG samples were dried at different temperatures (50, 60, 70, 80, 90, and 105°C) and analyzed for their moisture ratio, water activity, total polyphenol content (TPC), and DPPH (1,1-diphenyl-2-picrylhydrazil) radical scavenging activity. Also, four kinetics models were fitted to the drying data. Results:It was determined that the effective diffusivity was between 5.23x10

Antecedentes: El Bagazo residual de malta (BSG por sus siglas en inglés) es un subproducto biomásico generado en grandes volúmenes durante la producción industrial de cerveza. El BSG se ha convertido en un creciente problema para el medio ambiente, debido a que la mayoría de las cervecerías descartan inapropiadamente este residuo generando un impacto negativo al ambiente. Las alternativas para el aprovechamiento de este subproducto han consistido especialmente en la elaboración de suplementos alimenticios para animales de granja, obtención de biocombustibles, desarrollo de adsorbentes y obtención de productos para la industria alimentaria. Sin embargo, el alto contenido de humedad (~70%) del BSG representa un reto para el desarrollo de diferentes alternativas de reutilización, por lo que se hace necesario un proceso de secado previo. Objetivos: En este estudio se analizó la cinética de secado del BSG a diferentes temperaturas y el efecto de la temperatura de secado sobre sus propiedades físicas y contenido de compuestos bioactivos. Métodos: Las muestras de BSG fueron secadas a diferentes temperaturas (50, 60, 70, 80, 90 y 105°C) y analizadas en términos de razón de humedad, actividad acuosa, contenido de polifenoles totales (TPC) y actividad secuestradora del radical DPPH. Además, se ajustaron 4 modelos cinéticos a los datos de secado. Resultados: Se determinó que la difusividad efectiva del BSG varió entre 5.23x10

Fabrication of 1,4-alpha-D-glucan glucanohydrolase holding Gel-Scaffolds using Agar-Agar, a natural polysaccharide and Polyacrylamide, a synthetic organic polymer for continuous liquefaction of starch

1,4-alpha-D-glucan glucanohydrolase is among the most widely used commercial hydrolytic enzymes acting randomly on the glycosidic linkages of starch resulting in its saccharification and liquefaction. Its applicability in different industries can be improved by enhancing its stability and reusability. Therefore, in the present study attempts have been made to enhance the industrial applicability of 1,4-alpha-D-glucan glucanohydrolase from Bacillus subtilis KIBGE-HAR by adapting immobilization technology. The study developed mechanically stable, enzyme containing gel-frameworks using two support matrices including agar-agar, a natural polysaccharide and polyacrylamide gel, a synthetic organic polymer. These catalytic gel-scaffolds were compared with each other in terms of kinetics and stability of entrapped 1,4-α-D-glucan glucanohydrolase. In case of polyacrylamide gel, Km value for immobilized enzyme increased to 7.95 mg/mL, while immobilization in agar-agar resulted in decreased Km value i.e 0.277 mg/mL as compared to free enzyme. It was found that immobilized enzyme showed maximum activity at 70 °C in both the supports as compared to free enzyme having maximum activity at 60 °C. Immobilized 1,4-α-D-glucan glucanohydrolase exhibited no change in optimal pH 7.0 before and after entrapment in polyacrylamide gel and agar-agar. The enzyme containing gel-scaffold was found suitable for repeated batches of starch liquefaction in industrial processes. Agar-agar entrapped 1,4-α-D-glucanglucanohydrolase was capable to degrade starch up to seven repeated operational cycles whereas polyacrylamide entrapped enzyme conserved its activity up to sixth operational cycle.

Análise cinética e cinemática da saída de bloco em natação de atletas deficientes visuais / Kinetic and kinemaic analysis of block start in swimming in visually impaired athletes

Objetivos: investigar e correlacionar a cinética e cinemática da saída de bloco em natação de atletas deficientes visuais e normovisuais. Métodos: foram comparados parâmetros de desempenho entre os nadadores de ambos os sexos. A amostra contou com 16 nadadores, sendo 4 cegos, 2 baixa visão e 10 normovisuais. Análise inferencial com teste Shapiro-Wilk, estatística inferencial teste T e, para correlação entre variáveis, o teste de Pearson, com nível de significância em 5%. Correlacionamos a variável dinamométrica, nas fases de tempo de bloco, tempo em 5 metros e tempo em 16 metros. Resultados: foram percebidas diferenças significativas de (0,030, 0,029 e 0,001), respetivamente, pois foram menores para os nadadores normovisuais. Na variável cinética, o pico de força resultante dos nadadores normovisuais foi, significativamente, maior (0,024). O ângulo de saída dos nadadores normovisuais foi também, significativamente, maior (0,030). Nas fases de tempo de reação, tempo de voo, força horizontal e vertical, ângulo de entrada e distância de voo, não apresentaram diferenças significativas. Observou-se uma correlação expressiva, entre as variáveis tempo de bloco e tempo em 5 metros (0,688); tempo de bloco e tempo em 16 metros (0,689); tempo em 5 metros e tempo em 16 metros (0,928); e o tempo de voo e ângulo de saída (0,941). O pico de força apresentou uma correlação significativa na maioria das variáveis do estudo com exceção do tempo de reação e o ângulo entrada. Conclusão: a ausência da visão acarreta na defasagem da performance e nos resultados em provas de natação de alto rendimento para deficientes visuais.

Objectives: to investigate and correlate the kinetics and kinematics of the starting block in swimming of visually impaired and visually impaired athletes. Methods: The method used was to compare performance parameters between swimmers of both sexes. The sample had 16 swimmers being 4 blind, 2 low vision and, 10 normovisuals. Inferential analysis with Shapiro-Wilk test, inferential statistics T-test, and for correlation between variables the Pearson's test, with a significance level of 5%. We correlated the dynamometric variable, in the phases of block time, time in 5 meters and time in 16 meters. Results: Resulting in significant differences of (0.030, 0.029, and 0.001, block time, 5 and 16 meters respectively) lower for the normovisual swimmers. In the kinetic variable, the peak force resulting from normal-vision swimmers was significantly higher (0.024). The departure angle of normal-vision swimmers was also significantly higher (0.030). In the phases of reaction time, flight time, horizontal and vertical force, entry angle and flight distance, there were no significant differences. An expressive correlation was observed between the variables block time and time in 5 meters (0.688); block time and time on 16 meters (0.689); time on 5 meters and time on 16 meters (0.928); and flight time and departure angle (0.941). The force peak showed a significant correlation in most of the variables under study except for the reaction time and the imput angle. Conclusion: the absence of vision leads to a lack of performance and results in high-performance swimming tests.

Thin-layer drying characteristics, modeling and quality attributes of tomato slices dried with infrared radiation heating

An Infrared dryer was used to examine the drying of tomato slices. In this investigation, the influence of infrared radiation (IR) on the rate of drying, physical quality, energy combustion of tomato was estimated at three different levels of intensity at 0.15, 0.20, and 0.35 W/cm² under different air flows of 0.5, 1, and 1.5 m/s. Tomato slices were dried with an initial moisture content of 19.7 to 0.17 g water/g dry solids by infrared drying. The moisture content and drying rates are found to be dramatically affected by infrared density. An increase in the drying rate and a decrease in the drying period occurred with increasing infrared intensity. A decrease in energy consumption was detected with the increase of radiation intensity. The results clarified that the shrinkage ratio increased with increasing infrared intensity. The rehydration ratio raised with the increase in radiation intensity. The change in the colour difference of dried slices increased with an increase in radiation intensity. The models were in comparison using (R²) coefficient of determination, modelling efficiency (EF), and (χ²) reduced chi-square. Midilli model was fit for simulation of all drying conditions and could be used to estimate tomato moisture content at any time during the infrared drying process.

Blood glucose kinetics during concentric and eccentric muscle contractions

Studies comparing the two classes of stimuli (concentric and eccentric) have shown differences in the improvement of cardiovascular, metabolic, and muscle strength gain. This is an experimental, quantitative, and prospective study that aimed to verify the effect of eccentric exercise on glycolytic consumption and kinetics. The blood glucose kinetics of 17 male subjects was evaluated during a treadmill exercise with a 10% declined floor and velocity that required a 60% metabolic activity of VO2max, for 30 minutes. Seventy-two hours later, the same subjects exercised on the treadmill with a 10% inclined floor and 60% VO2max, for 30 minutes. To quantify glucose, blood samples were collected before the exercise, every three minutes along the 30 minutes of physical activity, and five and 10 minutes after finishing the exercise. For the downward slope, there was a homogeneous group behavior for blood glucose dynamics during the exercise, which was characterized by a monotonic decrease of glucose levels until reaching a minimum value at experimental times between 20 and 30 min, followed by a progressive recovery toward initial values. For the acclivity condition, blood glucose dynamics did not follow such a homogeneous behavior. A set of different types of dynamics could be identified. Experimental data showed that the type of dynamics could be predicted, to some extent, by the basal blood glucose level of subjects. The type of floor slope (upward or downward) directly affected glycolytic consumption and kinetics for the individuals analyzed.

Studies on the enzymatic specificity of diguanylate cyclases domains and the production of new second messengers / Estudos na especificidade enzimática de diguanilato ciclases e na produção de novos segundos mensageiros

In the first chapter, studies on substrate recognition and enzymatic activity of GGDEF domains are presented. Many proteins containing GGDEF domains are diguanylate cyclases (DGCs, EC 2.7.7.65), enzymes that catalyze the conversion of 2 GTP molecules into the second messenger c-di-GMP in prokaryotes. This molecule is primarily implicated in the transition between motile and sessile lifestyles, as well several other phenotypes. Redundancy and diversity of GGDEF domain sequences in many bacterial genomes raises the possibility that other enzymatic functions may yet be discovered. To test this hypothesis, i) the effect of point mutations on the structure and enzymatic activity of GGDEF domains is analyzed, ii) the enzymatic specificity of wild-type GGDEF domains from different proteins is also tested, and iii) when non-canonical products are detected, enzymatic models are studied to understand its preferential production. The principal results obtained from these studies are as follows. Seven mutants of the DGC PleD (a GGDEF containing-protein from Caulobacter crescentus) were constructed and the crystallographic structure of two of them was solved, showing that they are unlikely to bind the guanine moiety in its active site. Additionally, five mutants of XAC0610, another DGC from Xanthomonas citr, were constructed and their substrate specificities were evaluated. None of those mutants were able to use ATP as a substrate. Finally, seven different GGDEF domain-containing DGCs from different sources were expressed and purified and their enzymatic specificities were tested with several nucleotide triphosphates. One enzyme, GSU1658 from Geobacter sulfurreducens was particularly promiscuous and shown to produce c-di-GMP, c-di-AMP, c-di-IMP, c-di-2´dGMP, cGAMP, c-GIMP, and c-AIMP. Interestingly, XAC0610 was able to recognize 2´dGTP as substrate. Analysis of enzyme kinetics of XAC0610 in presence of 2´dGTP and/or GTP showed the preferential formation of the hybrid linear product pppGp2´dG. The second chapter present studies on cyanide metabolism in Bacillus with focus on the cyanide dihydratase of Bacillus safensis. Cyanide is widely used in industries due to its high affinity for metals. This same ability confers potent toxicity to this compound. Thus, industries must reduce the cyanide concentration from wastewater before its final disposal. Physical, chemical, and biological methods have been developed to achieve this goal, but knowledge about metabolic pathways and the biology of enzymes involved in cyanide degradation is still scarce. Here, the isolation of a Bacillus safensis strain from mine tailings in Peru is described. Classification of this strain was done through a comparative analysis of 132 core genomes of strains from the Bacillus pumilus group. Sequence analysis determined that a cyanide dihydratase (CynD, EC 3.5.5.1)) encoded in the genome of the isolated strain was likely the enzyme responsible for cyanide degradation. Confirmation of the cyanide degrading activity of CynD from this strain was achieved by cloning, expression and purification of the enzyme and its enzymatic characterization. CynD from this strain was active up to pH 9 and oligomerization patterns analyzed by SEC-MALS and electron microscopy showed that the enzyme forms large helical structures at pH 8 and smaller structures at higher pHs. Finally, we show that CynD expression is strongly induced in the presence of cyanide. The last two years of graduate studies were carried out in the context of the COVID-19 pandemic. Thanks to the large amount of publicly available genomic data, we were able to carry out studies on the worldwide dynamics of the spread of SARS-CoV-2 mutants forms. In the first year of the pandemic, genomic classification of 171,461 genomes showed the presence of five major haplotypes based on nine mutations. The worldwide distribution and the temporal evolution of frequency of these haplotypes was carefully analyzed. All the haplotypes were identified in the six regions analyzed (South America, North America, Europe, Asia, Africa, and Oceania); however, the frequency of each of them was different in each of these regions. As of September 30, 2020, haplotype 3 (or operational taxonomic unit 3, OTU_3) was the most prevalent in four regions (South America, Asia, Africa, and Oceania). OTU_5 was the most prevalent in North America and OTU_2 in Europe. Temporal dynamics of the haplotypes showed that OTU_1 became nearly extinct after 8 months of pandemic (November 2020). Other OTUs are still present in different frequencies all around the world, while currently generating new variants. Based on their temporal dynamics, a classification scheme of 115 SARS-CoV-2 mutations identified from 1,058,020 SARS-COV-2 genomes was also performed. Three types of temporal dynamics of mutations were identified: i) High-Frequency mutations are characterized by a rapid increase in frequency upon its appearance, ii) medium and iii) low-frequency mutations maintain mid or low-frequencies for several months and can be region-specific. Finally, we performed a correlation analysis of the effective reproduction number (Rt) of SARS-CoV-2 harboring the high-frequency mutation N501Y with the level of control measures adopted in specific jurisdictions. We show that Rt is negatively correlated with the level of control measures in eight of the nine countries analyzed. This negative correlation was similar when we analyzed the Rt of SARS-CoV-2 not-harboring N501Y. Thus, the control measures likely diminish the Rt of both SARSCoV-2 wild-type and N501Y

O presente trabalho está dividido em três capítulos sobre linhas de pesquisa diferentes desenvolvidas pelo autor durante o período de doutorado No primeiro capítulo, são apresentados estudos relacionados ao reconhecimento estrutural de substratos e análise enzimática de domínios GGDEF com atividade diguanilato ciclase (EC 2.7.7.65). As proteínas contendo domínios GGDEF estão relacionados à produção enzimática do segundo mensageiro c-di-GMP, a partir de duas moléculas de GTP, em procariotos. Esta molécula está principalmente envolvida na transição entre os estilos de vida móveis e sésseis, bem como vários outros fenótipos. Redundância e diversidade de sequências de domínio GGDEF aumentam a possibilidade de que outras funções enzimáticas ainda possam ser descobertas. Para testar esta hipótese, i) o efeito de mutações pontuais na estrutura e atividade enzimática dos domínios GGDEF é analisado, ii) a especificidade enzimática de domínios GGDEF de enzimas diferentes também é testada e iii) quando produtos não canônicos são detectados, modelos enzimáticos são estudados para entender sua produção preferencial. Como resultados mais importantes, sete mutantes do PleD (uma proteína contendo GGDEF) foram construídos e a estrutura cristalográfica de dois delas foi resolvida, mostrando que é improvável que eles liguem à porção guanina em seu sítio ativo. Além disso, cinco mutantes da proteína XAC0610 de Xanthomonas citri foram construídos e sua capacidade de usar ATP ou GTP como substrato foi avaliada. Nenhum desses mutantes foi capaz de usar ATP como substrato. Finalmente, sete outras proteínas contendo GGDEF foram purificadas e sua especificidade enzimática foi avaliada com vários trifosfatos de nucleotídeos. Uma enzima promíscua chamada GSU1658 mostrou produzir c-di-GMP, c-di-AMP, c-di-IMP, c-di-2´dGMP, c-GAMP, cGIMP e c-AIMP. Curiosamente, o XAC0610 foi capaz de reconhecer 2´dGTP como substrato. A análise da cinética enzimática de XAC0610 na presença de 2´dGTP e GTP mostrou a formação preferencial do produto linear híbrido pppGp2´dG. O segundo capítulo aborda estudos sobre o metabolismo do cianeto em Bacillus com foco na cianeto dihidratase de Bacillus safensis. O cianeto é amplamente utilizado nas indústrias devido à sua alta afinidade com os metais. Esta mesma capacidade confere toxicidade potente a este composto. Assim, as indústrias têm que reduzir a concentração de cianeto das águas residuais antes de sua disposição final. Métodos físicos, químicos e biológicos têm sido desenvolvidos para atingir esse objetivo, mas o conhecimento sobre as vias metabólicas e a biologia das enzimas envolvidas na degradação do cianeto ainda é escasso. Aqui, é descrito o isolamento de uma cepa de Bacillus safensis de rejeitos de minas no Peru. A classificação desta cepa foi feita através de uma análise comparativa de 132 core genomes de cepas do grupo de Bacillus pumilus. Em seguida, determinamos que uma cianeto dihidratase (CynD, EC 3.5.5.1) codificada no genoma da cepa isolada era provavelmente a enzima responsável pela degradação do cianeto. A confirmação da atividade degradante de cianeto de CynD desta cepa foi feita por clonagem, expressão e purificação da enzima e realização de caracterização enzimática. O CynD desta cepa é ativo até pH 9 e os padrões de oligomerização analisados por SEC-MALS mostraram que a enzima forma longas estruturas helicoidais em pH 8 e estruturas menores enquanto o pH aumenta. Finalmente, foi demonstrado que a expressão de CynD é fortemente induzida na presença de cianeto. Os últimos dois anos do doutorado foram realizados no contexto da pandemia COVID- 19. Vários laboratórios se dedicaram a gerar conhecimento para ajudar no combate à pandemia. Nesta situação e graças à grande quantidade de dados genômicos disponíveis publicamente, estudos sobre a dinâmica das mutações do SARS-CoV-2 foram realizados. No primeiro ano da pandemia, a classificação genômica de 171.461 genomas mostrou a presença de cinco haplótipos principais com base em nove mutações. A distribuição mundial e a mudança de frequência desses haplótipos foram analisadas cuidadosamente. Todos os haplótipos foram identificados nas seis regiões analisadas (América do Sul, América do Norte, Europa, Ásia, África e Oceania); no entanto, a frequência de cada um deles foi diferente em cada uma dessas regiões. Em 30 de setembro de 2020, o haplótipo 3 (ou unidade taxonômica operacional 3, OTU_3) era o mais prevalente em quatro regiões (América do Sul, Ásia, África e Oceania). OTU_5 foi o mais prevalente na América do Norte e OTU_2 na Europa. A dinâmica temporal dos haplótipos mostrou que OTU_1 parece perto da extinção após 8 meses de pandemia (novembro de 2020). Outros OTUs ainda estão presentes em diferentes frequências em todo o mundo, mesmo atualmente gerando novas variantes. Com base em sua dinâmica temporal, um esquema de classificação de 115 mutações SARS-CoV-2 identificadas a partir de 1.058.020 genomas SARS-COV-2 também foi feito. Três tipos de dinâmica temporal de mutações foram identificados: i) Mutações de alta frequência, ii) mutações de média frequência e iii) mutações de baixa frequência. Finalmente, foi analisada a correlação do número de reprodução efetiva (Rt) do SARS-CoV-2 que contém a mutação de alta frequência N501Y com o nível de medidas de controle, mostrando que seu Rt está negativamente correlacionado com o nível de medidas de controle em oito dos nove países analisados. Esta correlação negativa foi semelhante quando foi analisado o Rt de SARS-CoV-2 sem a mutação N501Y. Assim, as medidas de controle provavelmente diminuirão o Rt de SARS-CoV-2 tipo selvagem e N501Y

The influence of subtalar axis orientation on the foot posture of older adults in a closed kinetic chain / A influência da orientação do eixo subtalar na postura do pé de idosos em cadeia cinética fechada

Objectives: This study compared the influence of subtalar axis position on foot behavior in a closed kinetic chain in older and younger adults. Methods: The sample included 50 older adults and a control group of 50 younger adults. The variables were initially analyzed for both feet together, and were later analyzed separately, comparing each foot (right and left) between groups. Range of motion was assessed by validated goniometric procedures: the position of subtalar axis was evaluated by the palpation technique, while the Foot Posture Index was used to assess behavior in a closed kinetic chain. Student's t-test / Mann-Whitney test compared the main variables according to sample distribution, while Student's t-test / Wilcoxon test was used for paired samples. A standardized Haberman residuals test was also used to determine the connection between the position of subtalar joint axis and the Foot Posture Index. Results: Data from the right and left feet were similar for all variables. The older group had reduced mobility in the ankle and first metatarsophalangeal joint (5.42º [SD (Standard Deviation), 4.49] and 76.12º [SD, 19.24], respectively) with statistically significant values, (p <0.001), as measured by the Mann-Whitney test for the ankle joint and the t-Sutdent test for the first metatarsophalangeal joint, while the younger group had normal values (11.46º [SD, 6.49] and 97.17º [SD, 13.65], respectively)(p < 0.001). The difference in subtalar axis position was not significant (p = 0.788), with more internal deviations in both groups. There was a significant difference in Foot Posture Index (p = 0.006, by applying the chi-square test), with the normal position more prevalent in the older group and the prone position more prevalent in the younger group. Conclusions: Regarding internal deviations in the subtalar joint axis, the older group had a higher frequency of feet in the normal position, while the younger group had a higher frequency of feet in the prone position which, in this case, agrees with the rotational balance theory. For the normal axis position, a higher frequency of normal position was found in both groups. Regarding external deviations of the subtalar joint axis, neither group followed the pattern expected in rotational balance theory. The most consistent connection in the older group was between external axis position and supine foot position, whereas in the younger group it was between normal axis position and normal foot position.

Objetivos: Este estudo comparou a influência da posição do eixo subtalar no comportamento do pé em cadeia cinética fechada em idosos e adultos jovens. Metodologia: O grupo amostral incluiu 50 idosos e o grupo controle, 50 adultos jovens. As variáveis foram estudadas inicialmente para ambos os pés e comparadas entre os grupos, sendo posteriormente analisadas separadamente, comparando-se cada pé (direito e esquerdo) entre os grupos. A amplitude de movimento articular foi avaliada por procedimentos goniométricos validados; a posição do eixo subtalar foi avaliada pela técnica de palpação; o Foot Posture Index foi utilizado para avaliar o comportamento do pé em uma cadeia cinética fechada. O teste t de Student/teste de Mann-Whitney comparou as principais variáveis de acordo com a distribuição amostral, enquanto o teste t de Student/teste de Wilcoxon foi utilizado para amostras emparelhadas. O teste de resíduais ajustados de Haberman padronizado foi usado para a relação entre a posição do eixo da subtalar e o Foot Posture Index. Resultados: Os dados dos pés direito e esquerdo foram semelhantes para todas as variáveis. O grupo mais velho apresentou mobilidade reduzida no tornozelo e na primeira articulação metatarsofalângica (5,42 [desvio padrão ­ DP, 4,49] e 76,12 [DP, 19,24] graus, respectivamente), enquanto o grupo mais jovem apresentou valores normais (11,46 [DP, 6,49] e 97,17 [DP, 13,65], respetivamente) com valores estatisticamente significativos, (p <0,001), aferidos pelo teste de Mann-Whitney para a articulação do tornozelo e pelo teste t-Sutdent para a primeira articulação metatarsofalângica. A diferença na posição do eixo subtalar não foi significativa (p = 0,788, pela aplicação do teste de Qui-quadrado), com mais desvios internos em ambos os grupos. O Foot Posture Index diferiu significativamente entre os grupos (p = 0,006 pela aplicação do teste de Qui-quadrado), sendo a postura normal mais prevalente no grupo mais velho e a postura pronada mais prevalente no grupo mais jovem. Conclusões: Em relação aos desvios internos do eixo da articulação subtalar, o grupo mais velho apresentou maior frequência de pés na postura normal, enquanto o mais jovem apresentou maior frequência de pés pronados, o que, neste caso, corrobora a teoria do equilíbrio rotacional. Na posição normal do eixo, foi encontrada maior frequência de pés com postura normal em ambos os grupos. Em relação aos desvios externos do eixo da articulação subtalar, nenhum dos grupos seguiu o padrão esperado na teoria do equilíbrio rotacional. A relação mais consistente no grupo mais velho foi entre a posição do eixo externo e a posutra supinada do pé, enquanto no grupo mais jovem se deu entre a posição normal do eixo e a postura normal do pé

Formulation of stomach-specific floating microparticles of nizatidine and their radiographic evaluation

Nizatidine is an anti-secretogogue and a gastroprotective drug with a half-life of 1-2 h and is well absorbed in the stomach. This study aimed to optimize the process and develop floating microparticles of nizatidine that are based on low methoxyl pectin. Oil-in-oil dispersion method and Taguchi orthogonal array design were employed, and the prolonged residence time of the microparticles in the stomach was demonstrated. The constraints for independent variables, viz. A-polymer, B-internal solvent volume, C-surfactant, D-stirring rate and E-stirring time were set to generate the experimental runs. Particle size, percentage yield, micromeritic properties, entrapment efficiency, in vitro buoyancy and in vitro release were characterized. Surface morphology, zeta potential, in vitro release kinetics and in vivo floating performance of the optimized formulation was examined. The microparticles were free-flowing, irregular in shape and had a mean particle size distribution of 73-187 µ. Low methoxyl pectin played a predominant role in achieving buoyancy and optimum gastric retention for the modified release of the drug, suggesting Korsmeyer-Peppas model as the possible release mechanism. In vivo radiographic study in rabbits revealed that the drug was retained in the stomach for a period of 6 h. These results indicate that nizatidine floating microparticulate system provides modified drug release for the effective treatment of gastric ulcer

Optimization of Diltiazem hydrochloride osmotic formulation using QBD approach

Abstract Diltiazem hydrochloride (DLH) is a calcium channel blocker useful for the treatment of angina pectoris, arrhythmia, and hypertension. DLH having a short half-life needs frequent administration for successful treatment but this poses a problem of poor patient compliance. These requirements are served by elementary osmotic pump tablets (EOP) based controlled-release (CR) systems. Quality by design (QbD) approach assists in screening various factors with subsequent assessment of critical parameters that can have a major impact on the scalability of EOP. Tablets were formulated using wet granulation method followed by osmotic coating. Factorial design based QbD strategy aided in defining the risk assessment of influential variables such as hydrophilic polymers and osmotic coat component on the in-vitro release kinetics of the designed EOP tablets. These formulated EOP systems followed zero-order kinetics, a characteristic feature of EOPs. EOP tablets were formulated applying a systematic QbD statistical approach. The formulated DLH EOP systems with improved concentration-independent behavior helped to address the challenges of IR formulation. Application of QbD strategy in ascertaining the scalability of DLH EOP formulation would help pharmaceutical industries in the translation of EOP based drug delivery systems from R&D to market.

Momento aductor de la cadera durante la marcha en adultos mayores asintomáticos / Hip adductor moment during gait in asymptomatic older adults

Resumen Introducción: El momento articular durante la marcha se ha relacionado con diferentes procesos clínicos en la población adulto mayor, en Colombia no se cuentan con reportes propios. Objetivo: Analizar el momento aductor de la cadera durante la marcha de adultos mayores asintomáticos. Materiales y métodos: Se evaluó a 110 participantes siguiendo las referencias del software VICON NEXUS 2.8.1 modelo Full Body, se utilizó 2 plataformas de fuerza y el volumen de captura estuvo delimitado por 8 cámaras opto eléctricas Bonita 10. Se incluyó variables antropométricas, sociodemográficas, espaciotemporales y cinéticas durante la fase de apoyo, resaltando los dos picos máximos del momento aductor. Resultados: Las cifras del Pico Momento Aductor 1 y 2 (PMA1 y PMA2) fueron de 0,76 y 0,70 Nm/Kg respectivamente, estos picos se relacionaron con masa, talla e índice de masa corporal. Se construyó así una referencia para el análisis de adultos mayores asintomáticos. Conclusiones: La gráfica del momento aductor de la cadera es similar a la descrita por otros investigadores, pero en menor magnitud que en la población sintomática de coxartrosis.

Abstract Introduction: Although joint moment during waking has been associated with different clinical processes in the elderly population, there is a lack of reports in Colombia. Objective: To analyze the hip adductor moment during gait in asymptomatic older adults. Materials and methods: 110 participants were assessed using the VICON NEXUS 2.8.1. Full Body model software. 2 force platforms were used and the capture volume was delimited through 8 Bonita-10 optoelectronic cameras. Anthropometric, sociodemographic, spatiotemporal, and kinetic variables were included during the support phase, highlighting the two maximum peaks of the adductor moment. Results: The figures for Adductor Moment Peaks 1 and 2 (AMP1 and AMP2) were 0.76 and 0.70 Nm/Kg, respectively, which were related to mass, height and body mass index. Thus, a reference for the analysis of asymptomatic older adults was developed. Conclusion: The hip adductor moment graph is similar to that described by other researchers, but to a lesser extent than the values seen in coxarthrosis symptomatic population.

Scientific training of sports medicine for balance of knee joint muscle strength of athletes / Treinamento científico de medicina esportiva para equilíbrio da força muscular da articulação do joelho de atletas / Entrenamiento científico de la medicina deportiva para el equilibrio de la fuerza muscular de la articulación de la rodilla de los atletas

ABSTRACT Introduction: As skiers need to complete their movements in high mountains and snow, the athlete's landing's stability is directly related to the movement's success. The stable landing action wins high scores for the athletes' participating actions and protects their safety. Objective: This article analyzes the characteristics of lower limb muscle strength and static balance ability of female freestyle skiing aerials athletes to provide athletes with targeted strength training, evaluation of muscle effects after training, and athlete selection to provide a scientific basis valuable Theoretical reference. Methods: The paper uses isokinetic testing and balance testing methods to study the characteristics of the hip and knee flexor and extensor strengths of the Chinese great female freestyle skiing aerials athletes and the static balance characteristics in four standing positions. Results: The right flexor-extensor force, flexor-extensor force ratio, and average power value of the right hip joint were slightly greater than the left flexor power. The left and right knee joint extensor unit peak weight moments and the left and right average power values were all four indicators. Greater than the flexor, at different test speeds of 60°/s (slow speed) and 240°/s (fast), the peak flexion and extension torque per unit weight, the average power of flexion and extension, the force of flexion and extension, and the average power appear with the increase of the test speed as a significant difference. Conclusions: The research in the thesis recommends reasonable weight control and balanced training of muscle strength, using the condition of moderately increasing exercise speed, to strengthen the training of lower limb extensor strength, provide targeted strength training for athletes, evaluate the muscle effect after training and providing the scientific basis and valuable theoretical reference. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Introdução: Como os esquiadores precisam completar seus movimentos em altas montanhas e neve, a estabilidade de pouso do atleta está diretamente relacionada ao sucesso do movimento. A ação de pouso constante ganha altas pontuações para os participantes e protege sua segurança. Objetivo: este artigo discute as características da força muscular das extremidades inferiores e habilidade de equilíbrio estático de atletas de esqui estilo livre para fornecer aos atletas treinamento de força específico e avaliação pós-treino dos efeitos musculares em atletas selecionados para fornecer uma base científica de referência teórica valiosa. Métodos: O artigo usa testes isocinéticos e métodos de teste de equilíbrio para estudar as características de força dos flexores e extensores de quadril e joelho de grandes atletas chinesas de esqui estilo livre e as características de equilíbrio estático em quatro posições de pé. Resultados: A força flexor-extensora direita, a relação da força flexor-extensora e o valor médio da potência da articulação do quadril direito foram ligeiramente maiores do que a potência do flexor esquerdo. Os momentos máximos de peso da unidade extensora da articulação do joelho esquerdo e direito e os valores médios das potências esquerda e direita foram os quatro indicadores. Maior que o flexor, em diferentes velocidades de teste de 60 ° / s (velocidade lenta) e 240 ° / s (rápido), o torque máximo de flexão e extensão por unidade de peso, a força média de flexão e extensão, a força de flexão e extensão, e a potência média aparece com o aumento da velocidade de teste como uma diferença significativa. Conclusões: A pesquisa na tese recomenda o controle de peso razoável e o treinamento de força muscular balanceado, utilizando a condição de aumentar moderadamente a velocidade do exercício, para fortalecer o treinamento de força extensora de membros inferiores, fornecer treinamento de força específico para atletas, avaliando o efeito muscular após formar e fornecer a base científica e um valioso referencial teórico. Nível de evidência II; Estudos terapêuticos- investigação dos resultados do tratamento.

RESUMEN Introducción: Como los esquiadores necesitan completar sus movimientos en alta montaña y nieve, la estabilidad del aterrizaje del atleta está directamente relacionada con el éxito del movimiento. La acción de aterrizaje estable gana puntuaciones altas para las participantes y protege su seguridad. Objetivo: Este artículo analiza las características de la fuerza muscular de las extremidades inferiores y la capacidad de equilibrio estático de las atletas de esquí de estilo libre para proporcionar a los atletas un entrenamiento de fuerza específico y una evaluación de los efectos musculares después del entrenamiento en atletas seleccionados para proporcionar una base científica de referencia teórica valiosa. Métodos: El artículo utiliza pruebas isocinéticas y métodos de prueba de equilibrio para estudiar las características de la fuerza de los flexores y extensores de cadera y rodilla de las grandes atletas chinas de esquí de estilo libre femenino y las características del equilibrio estático en cuatro posiciones de pie. Resultados: La fuerza flexora-extensora derecha, la relación de fuerza flexora-extensora y el valor de potencia promedio de la articulación de la cadera derecha fueron ligeramente mayores que la potencia del flexor izquierdo. Los momentos de peso máximo de la unidad extensora de la articulación de la rodilla izquierda y derecha y los valores de potencia promedio izquierda y derecha fueron los cuatro indicadores. Mayor que el flexor, a diferentes velocidades de prueba de 60 ° / s (velocidad lenta) y 240 ° / s (rápido), el par máximo de flexión y extensión por unidad de peso, la potencia promedio de flexión y extensión, la fuerza de flexión y extensión, y la potencia media aparecen con el aumento de la velocidad de prueba como una diferencia significativa. Conclusiones: La investigación en la tesis recomienda un control de peso razonable y un entrenamiento equilibrado de la fuerza muscular, utilizando la condición de aumentar moderadamente la velocidad del ejercicio, para fortalecer el entrenamiento de la fuerza extensora de las extremidades inferiores, proporcionar entrenamiento de fuerza específico para los atletas, evaluar el efecto muscular después del entrenamiento y proporcionar la base científica y una valiosa referencia teórica. Nivel de evidencia II; Estudios terapéuticos- investigación de los resultados del tratamiento.

Potential application of a knowledgebase of iron metabolism of Acidithiobacillus ferrooxidans as an alternative platform

BACKGROUND: Acidithiobacillus ferrooxidans is a facultative anaerobe that depends on ferrous ion oxidation as well as reduced sulfur oxidation to obtain energy and is widely applied in metallurgy, environmental protection, and soil remediation. With the accumulation of experimental data, metabolic mechanisms, kinetic models, and several databases have been established. However, scattered data are not conducive to understanding A. ferrooxidans that necessitates updated information informed by systems biology. RESULTS: Here, we constructed a knowledgebase of iron metabolism of A. ferrooxidans (KIMAf) system by integrating public databases and reviewing the literature, including the database of bioleaching substrates (DBS), the database of bioleaching metallic ion-related proteins (MIRP), the A. ferrooxidans bioinformation database (Af-info), and the database for dynamics model of bioleaching (DDMB). The DBS and MIRP incorporate common bioleaching substrates and metal ion-related proteins. Af-info and DDMB integrate nucleotide, gene, protein, and kinetic model information. Statistical analysis was performed to elucidate the distribution of isolated A. ferrooxidans strains, evolutionary and metabolic advances, and the development of bioleaching models. CONCLUSIONS: This comprehensive system provides researchers with a platform of available iron metabolism-related resources of A. ferrooxidans and facilitates its application.

LXYL-P1-2 immobilized on magnetic nanoparticles and its potential application in paclitaxel production

BACKGROUND: LXYL-P1-2 is the first reported glycoside hydrolase that can catalyze the transformation of 7-b-xylosyl-10-deacetyltaxol (XDT) to 10-deacetyltaxol (DT) by removing the D-xylosyl group at the C7 position. Successful synthesis of paclitaxel by one-pot method combining the LXYL-P1-2 and 10- deacetylbaccatin III-10-b-O-acetyltransferase (DBAT) using XDT as a precursor, making LXYL-P1-2 a highly promising enzyme for the industrial production of paclitaxel. The aim of this study was to investigate the catalytic potential of LXYL-P1-2 stabilized on magnetic nanoparticles, the surface of which was modified by Ni2+-immobilized cross-linked Fe3O4@Histidine. RESULTS: The diameter of matrix was 20­40 nm. The Km value of the immobilized LXYL-P1-2 catalyzing XDT (0.145 mM) was lower than that of the free enzyme (0.452 mM), and the kcat/Km value of immobilized enzyme (12.952 mM s 1 ) was higher than the free form (8.622 mM s 1 ). The immobilized form maintained 50% of its original activity after 15 cycles of reuse. In addition, the stability of immobilized LXYL-P1-2, maintained 84.67% of its initial activity, improved in comparison with free form after 30 d storage at 4 C. CONCLUSIONS: This investigation not only provides an effective procedure for biocatalytic production of DT, but also gives an insight into the application of magnetic material immobilization technology.

Isokinetic strength, bilateral and unilateral strength differences: variation by age and laterality in elite youth football players / Fuerza isocinética, diferencias de fuerza bilaterales y unilaterales: variación por edad y lateralidad en futbolistas juveniles de élite

SUMMARY: The purpose of this study was to investigate the effect of age on peak torque (PT) relative strength measures of knee extensors (KE) and knee flexors (KF), bilateral strength ratio (Q:Q, H:H), and ipsilateral strength ratio (H:Q) in youth elite male football players.Elite male players (n = 70) from four age categories (U16: n = 20, U17: n = 20, U19: n = 15, U21: n = 15) performed isokinetic strength tests using a Cybex dynamometer. Results show a significant effect of age on PTKE (F3,142 = 4.54, p = 0.005, = 0.09) and PTKF (age: F3,142 = 3.07, p = 0.030, = 0.06). No significant effect of age on unilateral (F3,142 = 1.05, p = 0.375, = 0.02) or ipsilateral strength ratio (F3,142 = 2.63, p = 0.053, = 0.06) was found. Results revealed significant differences in PTKE for nondominant limbs between U16 and U21. Higher bilateral differences were detected for flexors (H:H = 7.94-11.47 %, Q:Q = 7.97-9.29 %) compared to extensors. Our study showed that 17-year-old players have levels of strength similar to U19 players. A higher bilateral difference of knee flexors than extensors was found, suggesting that more attention should be paid to knee flexors. No effect of laterality was found for strength and strength asymmetries. Future research should also focus on ipsilateral strength ratio in late stage of maturation.

RESUMEN: El objetivo de este estudio fue investigar el efecto de la edad en las medidas de fuerza relativa de torque máximo (TM) de los extensores de rodilla (ER) y flexores de rodilla (FR), la relación de fuerza bilateral (Q: Q, H: H) y la relación de fuerza ipsilateral (H: Q) en jugadores de fútbol masculino de élite en 70 sujetos de cuatro categorías de edad (U16: n = 20, U17: n = 20, U19: n = 15, U21: n = 15). Se realizaron pruebas de fuerza isocinética utilizando un dinamómetro Cybex. Los resultados mos- traron un efecto significativo de la edad en TMER (F3,142 = 4,54, p = 0,005, = 0,09) y TMFR (edad: age: F3,142 = 3,07, p = 0,030, = 0,06). No se observó efecto significativo alguno de la edad sobre la fuerza unilateral (F3,142 = 1,05, p = 0,375, = 0,02) o relación de fuerza ipsilateral (F3,142 = 2,63, p = 0,053, = 0,06). Los resultados indicaron diferencias significativas en TMER para miembros no dominantes entre U16 y U21. Se detectaron mayo- res diferencias bilaterales para los flexores (H:H = 7,94-11,47%, Q:Q = 7,97-9,29 %) en comparación con los extensores. Nues- tro estudio mostró que los jugadores de 17 años tienen niveles de fuerza similares a la de los jugadores sub-19. Se observó una mayor diferencia bilateral de flexores de rodilla que de extensores, lo que sugiere que se debe prestar más atención a los flexores de rodilla. No se encontró un efecto de lateralidad para fuerza y asimetrías de fuerza. Los estudios futuros también deben centrarse en la relación de fuerza ipsilateral en la etapa tardía de maduración.

Identification and characterization of a novel 2R, 3R-Butanediol dehydrogenase from Bacillus sp. DL01

BACKGROUND: 2R,3R-butanediol dehydrogenase (R-BDH) and other BDHs contribute to metabolism of 3R/3S-Acetoin (3R/3S-AC) and 2,3-butanediol (2,3-BD), which are important bulk chemicals used in different industries. R-BDH is responsible for oxidizing the hydroxyl group at their (R) configuration. Bacillus species is a promising producer of 3R/3S-AC and 2,3-BD. In this study, R-bdh gene encoding R-BDH from Bacillus sp. DL01 was isolated, expressed and identified. RESULTS: R-BDH exerted reducing activities towards Diacetyl (DA) and 3R/3S-AC using NADH, and oxidizing activities towards 2R,3R-BD and Meso-BD using NAD+ , while no activity was detected with 2S,3S-BD. The R-BDH showed its activity at a wide range of temperature (25 C to 65 C) and pH (5.0­8.0). The R-BDH activity was increased significantly by Cd2+ when DA, 3R/3S-AC, and Meso-BD were used as substrates, while Fe2+ enhanced the activity remarkably at 2R,3R-BD oxidation. Kinetic parameters of the R-BDH from Bacillus sp. DL01 showed the lowest Km, the highest Vmax, and the highest Kcat towards the racemic 3R/3S-AC substrate, also displayed low Km towards 2R,3R-BD and Meso-BD when compared with other reported R-BDHs. CONCLUSIONS: The R-BDH from Bacillus sp. DL01 was characterized as a novel R-BDH with high enantioselectivity for R-configuration. It considered NAD+ and Zn2+ dependant enzyme, with a significant affinity towards 3R/3S-AC, 2R,3R-BD, and Meso-BD substrates. Thus, R-BDH is providing an approach to regulate the production of 3R/3S-AC or 2,3-BD from Bacillus sp. DL01.

Block slope is the main determinant of block phase performance in swimming / A inclinação do bloco é o principal determinante do desempenho da fase de bloco em natação / La inclinación del bloque es el principal determinante del desempeño de la fase de bloque en natación

ABSTRACT Introduction Swimming starts are an important component for decreasing the total race time, especially in short events. In this phase of swimming, the aim is to increase performance using many different techniques and starting platforms. Objectives The effects of height and slope of the starting block on kick-start performance were assessed in this study. Methods Six male competitive swimmers performed 24 kick-starts using four block settings: 65 cm & 75 cm flat and 65 cm & 75 cm sloped. Two-dimensional kinetic and three-dimensional kinematic data were analyzed, including average and maximum horizontal/vertical forces and impulses; reaction times; movement and block times; and take-off vertical/horizontal velocities. Two-way within-subject design ANOVAs were implemented to test the effects of block height and slope on the kinetic and kinematic variables. Results Block slope was the main factor affecting most of the dependent variables. Shorter block and movement times, greater average and maximum vertical forces, vertical impulse, and maximum horizontal force were found for the sloped settings. An inverse relationship was found between block height and 0-5 m times. Conclusion Based on the results, blocks with height of 75 cm and slope of 10° provided better results in swimmers' performance in the block phase. Level of evidence II, Therapeutic Studies -Investigating the Results of Treatment

RESUMO Introdução As largadas de natação são um componente importante para reduzir o tempo total de competição, especialmente em eventos curtos. Nessa fase da natação, o objetivo é aumentar o desempenho usando várias técnicas e plataformas de largada distintas. Objetivos Neste estudo, foram avaliados os efeitos da altura e da inclinação da plataforma sobre desempenho da saída kick-start. Métodos Seis nadadores de competição do sexo masculino realizaram 24 largadas, usando quatro tipos de bloco de partida (65 cm e 75 cm de altura planos e 65 cm e 75 cm com inclinação). Foram analisados dados cinéticos bidimensionais e cinemáticos tridimensionais, incluindo forças e impulsos horizontais/verticais médios e máximos; tempos de reação, movimento e de bloco; e velocidades vertical/horizontal da decolagem. Empregou-se o método ANOVA bidirecional intraindivíduo para analisar os efeitos da altura e da inclinação do bloco sobre as variáveis cinéticas e cinemáticas. Resultados A inclinação do bloco foi o principal fator que afetou a maioria das variáveis dependentes. Nas plataformas de largada inclinadas, verificou-se que os tempos de bloco e movimento eram mais curtos e as forças verticais médias e máximas, o impulso vertical e a força horizontal máxima foram maiores nas configurações inclinadas. Foi encontrada uma relação inversa entre a altura do bloco e os tempos para as distâncias de 0 a 5 metros. Conclusões Com base nos resultados, os blocos com 75 cm de altura e 10 graus de inclinação forneceram melhores resultados de desempenho dos nadadores na fase de bloco. Nível de Evidência II - Investigação dos resultados do tratamento.

RESUMEN Introducción Las largadas de natación son un componente importante para reducir el tiempo total de competición, especialmente en eventos cortos. En esta fase de natación, el objetivo es aumentar el desempeño usando varias técnicas y plataformas de largada distintas. Objetivos En este estudio, fueron evaluados los efectos de la altura y de la inclinación de la plataforma sobre desempeño de la salida kick-start. Métodos Seis nadadores de competición del sexo masculino realizaron 24 largadas, usando cuatro tipos de bloque de partida (65 cm y 75 cm de altura planos y 65 cm y 75 cm con inclinación). Fueron analizados datos cinéticos bidimensionales y cinemáticos tridimensionales, incluyendo fuerzas e impulsos horizontales/verticales promedios y máximos; tiempo de reacción, movimiento y de bloque; y velocidades vertical/horizontal del despegue. Se empleó el método ANOVA bidireccional intraindividuo para analizar los efectos de la altura y de la inclinación del bloque sobre las variables cinéticas y cinemáticas. Resultados La inclinación del bloque fue el principal factor que afectó a la mayoría de las variables dependientes. En las plataformas de largada inclinadas, se verificó que los tiempos de bloque y movimiento eran más cortos y las fuerzas verticales promedio y máximas, el impulso vertical y la fuerza horizontal máxima fueron mayores en las configuraciones inclinadas. Fue encontrada una relación inversa entre la altura del bloque y los tiempos para las distancias de 0 a 5 metros. Conclusiones Con base en los resultados, los bloques con 75 cm de altura y 10 grados de inclinación proporcionaron mejores resultados de desempeño de los nadadores en la fase de bloque. Nivel de Evidencia II; Investigación de los resultados del tratamiento

Vertical transmission and kinetic of antibodies anti-Neospora caninum in naturally infected lambs in the semiarid region of Brazil / Transmissão vertical e cinética de anticorpos anti-Neospora caninum em cordeiros naturalmente infectados na região Semiárida do Brasil

Abstract Aimed with this study to evaluate vertical transmission of Neospora caninum in naturally infected sheep and to monitor the kinetics of antibodies against this protozoon in their lambs. Therefore, 48 pregnant ewes, from five herds, were divided into two groups: G1 - positive for anti-N. caninum antibodies, with 19 animals; and G2 - seronegative, with 29 animals. Blood samples were taken from the ewes and their lambs, immediately after birth, before ingesting colostrum, and 2, 7, 14, 21, 28, 35, 42, 49 and 56 days after birth. Analysis on serum antibodies was performed using the indirect immunofluorescent antibody test. Among the 19 seropositive mothers, six (31.6%) gave birth to lambs seropositive before ingesting colostrum and it was found that these lambs remained positive until the end of the study (56 days). Only one of the lambs, from a ewe that presented an antibody titer of 200, seroconverted after ingestion of colostrum. All the lambs that had been born from negative mothers remained negative throughout the experimental period. It was concluded that transplacental transmission was an important form of diffusion of N. caninum in the herds studied and that seropositive lambs maintained circulating antibodies during the period analyzed.

Resumo Objetivou-se avaliar a ocorrência da transmissão vertical de Neospora caninum em ovelhas naturalmente infectadas e monitorar a cinética de anticorpos para esse protozoário nos cordeiros. Portanto, foram selecionadas 48 matrizes prenhes, provenientes de cinco propriedades, e estas foram divididas em dois grupos: G1- 19 matrizes positivas para anticorpos anti-N. caninum antes da prenhez; e G2 - 29 matrizes soronegativas. Foram realizadas colheitas sanguíneas nas mães e cordeiros, no G1 e G2, imediatamente após a parição, antes da ingestão do colostro. Também foi possível realizar colheitas de sangue com 2, 7, 14, 21, 28, 35, 42, 49 e 56 dias após o nascimento. A pesquisa de anticorpos séricos foi realizada por meio da Reação de Imunofluorescência Indireta (RIFI). Das 19 matrizes soropositivas, seis (31,6%) pariram cordeiros soropositivos antes da ingestão do colostro, os quais mantiveram-se positivos até o final do experimento (56 dias). Apenas um dos cordeiros, filho de uma ovelha com título de anticorpos 200, soroconverteu após ingestão do colostro. Todos os cordeiros, filhos de mães negativas, mantiveram-se negativos durante todo o período experimental. Conclui-se que a transmissão transplacentária é uma importante forma de difusão do N. caninum nos rebanhos estudados e que os descendentes infectados, durante a gestação, mantiveram anticorpos circulantes durante o período analisado.

Antimicrobial photodynamic inactivation mediated by methylene blue: Analysis of inactivation kinetics and biochemical mechanisms / Inativação fotodinâmica antimicrobiana mediada por azul de metileno: Análises de cinética de inativação e mecanismos bioquímicos

The widespread use of antimicrobial chemotherapy in medicine and livestock production imposed an evolutive selection of drug-resistant strains worldwide. As a result, the effectiveness of our current antimicrobial armamentarium is constantly being reduced to alarming levels. Therefore, novel antimicrobial therapeutic strategies are urgently needed. Antimicrobial photodynamic therapy (APDT) comes to this scenario as a powerful tool to counteract the emergence of microbial drug-resistance. Its mechanisms of action are based on simultaneous oxidative damage of multiple targets and, therefore, it is much less likely to allow any type of microbial resistance. Therefore, the objectives of this study were focused into establishing 1) a mathematical tool to allow precise analysis of microbial photoinactivation; 2) a broad analysis of APDT effectiveness against global priority drug-resistant pathogens; 3) inhibition of ßlactamase enzymes; and 4) how the biochemical mechanisms of APDT avoid emergence of resistance. The main results obtained through the investigation led by this thesis were divided into 4 scientific articles regarding each of the above-mentioned objectives. In summary, we discovered that 1) a power-law function can precisely fit all microbial inactivation kinetics data and provide insightful information of tolerance factors and lethal doses; 2) there is no correlation between drug-resistance and APDT sensitivity, i.e., extensively drug resistant microorganisms are killed in the same kinetics as drug-sensitive controls; 3) ß-lactamases are very sensitive to photodynamic inhibition; 4) biochemical mechanisms of APDT promote oxidative damages to external cell membranes, DNA and proteins whereas the main cause of microbial death seems to be directly associated with protein degradation. Thus, we conclude that APDT is effective against a broad-spectrum of pathogens and has minimum chances of promoting resistance mechanisms

O amplo uso da quimioterapia antimicrobiana impôs uma seleção evolutiva de cepas resistentes a medicamentos. Como resultado, a eficácia dos fármacos antimicrobianos tem sido reduzida a níveis alarmantes. Portanto, novas estratégias terapêuticas antimicrobianas são urgentemente necessárias. A terapia fotodinâmica antimicrobiana (TFDA) entra neste cenário como uma ferramenta poderosa para combater a resistência microbiana. Seus mecanismos de ação são baseados no dano oxidativo sobre múltiplos alvos e, portanto, é muito menos provável que permita o surgimento de qualquer tipo de resistência. Os objetivos deste estudo foram focados ao estabelecimento de 1) modelo matemático para análise precisa da fotoinativação microbiana; 2) ampla análise da eficácia da TFDA contra patógenos resistentes a fármacos antimicrobianos de prioridade global; 3) inibição de ß-lactamases por TFDA; e 4) como os mecanismos bioquímicos da TFDA evitam o surgimento de resistência. Os principais resultados obtidos através da investigação conduzida por esta tese foram divididos em 4 artigos científicos. Em resumo, descobrimos que 1) uma função de lei de potência pode ajustar com precisão todos os dados de cinética de inativação microbiana e fornecer informações detalhadas sobre fatores de tolerância e doses letais; 2) não há correlação entre resistência à quimioterapia antimicrobiana e sensibilidade à TFDA, isto é, cepas extensivamente resistentes aos antimicrobianos são inativadas sob a mesma cinética que controles sensíveis aos antimicrobianos; 3) ß-lactamases são altamente sensíveis à inibição fotodinâmica; 4) os mecanismos bioquímicos da TFDA promovem danos oxidativos às membranas celulares e DNA, porém, a principal causa de morte microbiana é diretamente associada à degradação das proteínas. Assim, concluímos que a TFDA é eficaz contra um amplo espectro de patógenos e tem chances mínimas de promover mecanismos de resistência