CHITOSAN HYDROGELS FOR DRUG DELIVERY AND TISSUE ENGINEERING APPLICATIONS

Chitosan has been extensively used to prepare hydrogel systems. The fact that chemically and ionically crosslinked chitosan hydrogels can slowly release drugs through swelling have enabled their use in drug delivery applications. In addition, the high porosity of these hydrogels ensures a more effective cell loading and depending on the pore size and interconnectivity, it can lead to cell differentiation and eventually tissue formation. The purpose of this review is to take a closer look at the use of chitosan hydrogels to prepare drug delivery systems and scaffolds for tissue engineering. Aspects involving chitosan structure, physicochemical properties and biological applications are also discussed. In addition, this article reviews the methods used to prepare chitosan hydrogels and the mechanisms involved in the release of drugs.Â

Fatal Motorcycle Crashes: A Serious Public Health Problem In Brazil.

The numbers of two-wheel vehicles are growing across the world. In comparison to other vehicles, motorcycles are cheaper and thus represent a significant part of the automobile market. Both the mobility and speed are attractive factors to those who want to use them for work or leisure. Crashes involving motorcyclists have become an important issue, especially fatal ones. Specific severe injuries are responsible for the deaths. Defining them is necessary in order to offer better prevention and a more suitable medical approach. All fatal motorcycle crashes between January 2001 and December 2009 in Campinas, Brazil, were analyzed in this study. Official data have been collected from police incident reports, hospitals' registers and autopsies. Both incidents and casualties were analyzed according to relevant variables. The Injury Severity Score (ISS) was calculated, describing the most potentially fatal injuries. There were 479 deaths; 90.8% were male; the mean age was 27.8 (range 0-73); 86.4% were conductors of the vehicles; blood alcohol was positive in 42.3%; 49.7% died at a hospital; 32.6% died at the scene; 26.1% of the accidents occurred at night, 69.1% were urban and 30.9% occurred on highways. The main causes of injury were collisions (63%) and falls (14%). The mean ISS was 38.5 (range 9-75). With regard to injuries, head trauma (67%) and thoracic trauma (40%) were the most common, followed by abdominal trauma (35%). Traumatic brain injury (67%) and hypovolemic shock (38%) were the most frequent causes of death. Alcohol was a significant factor in relation to the accidents. Head trauma was the most frequent and severe injury. Half of the victims died before receiving adequate medical attention, suggesting that prevention programs and laws should be implemented and applied in order to save future lives.7 Suppl 1S

Airflow-Restricting Mask Reduces Acute Performance in Resistance Exercise

Background: The aim of this study was to compare the number of repetitions to volitional failure, the blood lactate concentration, and the perceived exertion to resistance training with and without an airflow-restricting mask. Methods: Eight participants participated in a randomized, counterbalanced, crossover study. Participants were assigned to an airflow-restricting mask group (MASK) or a control group (CONT) and completed five sets of chest presses and parallel squats until failure at 75% one-repetition-maximum test (1RM) with 60 s of rest between sets. Ratings of perceived exertion (RPEs), blood lactate concentrations (Lac(-)), and total repetitions were taken after the training session. Results: MASK total repetitions were lower than those of the CONT, and (Lac(-)) and MASK RPEs were higher than those of the CONT in both exercises. Conclusions: We conclude that an airflow-restricting mask in combination with resistance training increase perceptions of exertion and decrease muscular performance and lactate concentrations when compared to resistance training without this accessory. This evidence shows that the airflow-restricting mask may change the central nervous system and stop the exercise beforehand to prevent some biological damage.Univ Fed Sao Paulo, Grp Studies & Res Exercise Physiol GEPEFEX, BR-11015020 Sao Paulo, BrazilCruzeiro Univ, Inst Phys Act Sci & Sport, BR-03342000 Sao Paulo, BrazilUniv Fed Sao Paulo, Grp Studies & Res Exercise Physiol GEPEFEX, Postgrad Program Human Movement Sci & Rehabiltat, BR-11015020 Sao Paulo, BrazilGroup of Studies and Research in Exercise Physiology (GEPEFEX), Universidade Federal de São Paulo (UNIFESP), São Paulo 11.015-020, BrazilPostgraduate Program in Human Movement Sciences and Rehabilitation, Group of Studies and Research in Exercise Physiology (GEPEFEX), Universidade Federal de São Paulo (UNIFESP), São PauloWeb of Scienc

Potential of maize (Zea mays L.) populations derived from commercial single-cross hybrids for extraction of partially inbred lines under different nitrogen availability

Extraction of inbred lines is a very important step in maize breeding since these lines will be used to obtain hybrids intended for the market. However, this expensive process, hinders genotype evaluation in contrasting environments, especially regarding nitrogen (N) content. This study aimed to evaluate the potential of maize populations for line extraction and select partially inbred lines under different soil nitrogen (N) availability. Five populations were evaluated regarding their potential for line extraction. Fifty-five S1 partially inbred lines were extracted from these populations. The top-cross method was used to evaluate lines by crossing them with two testers. Hybrids evaluation used 110 top-cross hybrids, five base populations, and six checks. Two trials were carried out in Dourados and Caarapó. One trial had adequate fertilization (high N) while the other was under stress condition (low N). Hybrid DKB 789 showed potential for extraction of partially inbred lines, aiming at selecting N use efficiency. Base population BP (07) was the most suitable for the extraction of partially inbred lines aiming at N use efficiency. Partially inbred lines BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids with high grain yield, efficiency, and responsiveness to N. Highlights Extraction of inbred lines is a very important step in maize breeding. Hybrid DKB 789 showed potential for extraction of partially inbred lines. BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids.Extraction of inbred lines is a very important step in maize breeding since these lines will be used to obtain hybrids intended for the market. However, this expensive process, hinders genotype evaluation in contrasting environments, especially regarding nitrogen (N) content. This study aimed to evaluate the potential of maize populations for line extraction and select partially inbred lines under different soil nitrogen (N) availability. Five populations were evaluated regarding their potential for line extraction. Fifty-five S1 partially inbred lines were extracted from these populations. The top-cross method was used to evaluate lines by crossing them with two testers. Hybrids evaluation used 110 top-cross hybrids, five base populations, and six checks. Two trials were carried out in Dourados and Caarapó. One trial had adequate fertilization (high N) while the other was under stress condition (low N). Hybrid DKB 789 showed potential for extraction of partially inbred lines, aiming at selecting N use efficiency. Base population BP (07) was the most suitable for the extraction of partially inbred lines aiming at N use efficiency. Partially inbred lines BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids with high grain yield, efficiency, and responsiveness to N. Highlights Extraction of inbred lines is a very important step in maize breeding. Hybrid DKB 789 showed potential for extraction of partially inbred lines. BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids

Métodos alternativos para estimar a velocidade da máxima fase estável de lactato em adultos jovens fisicamente ativos

The aim of this study was to compare the velocities found in the protocols used to measure the indirect individual anaerobic threshold (IATind), glucose threshold (GT) and critical velocity (CV) with the gold standard, the maximum lactate steady state (MLSS) protocol. Fourteen physically active young adults (23±3.1 years; 72±10.97 kg; 176±7 cm; 21±5.36% body fat) performed a 3000-m track running test to determine IATind using the prediction equation and an incremental test on a treadmill to determine GT. The CV was identified by linear regression of the distance-time relationship based on 3000-m and 500-m running performance. The MLSS was identified using two to five tests on different days to identify the intensity at which there was no increase in blood lactate concentration greater than 1 mmol/L between the 10th and 30th minute. A significant difference was observed between mean CV and MLSS (P≤0.05) and there was a high correlation between MLSS and IATind (R2=0.82; P≤0.01) and between MLSS and GT (R2=0.72; P≤0.01). The Bland-Altman method showed agreement between MLSS and IATind [mean difference -0.24 (confidence interval -1.72 to 1.24) km/h] and between MLSS and GT [0.21 (-1.26 to 1.29) km/h]. We conclude that the IATind and GT can predict MLSS velocity with good accuracy, thus making the identification of MLSS practical and efficient to prescribe adequate intensities of aerobic exercise.O objetivo do presente estudo foi comparar as velocidades encontradas nos protocolos de Limiar Anaeróbio Individual Indireto (LAIind), Limiar Glicêmico (LG) e Velocidade Crítica (VC) com o padrão ouro, o protocolo de identificação da máxima fase estável do lactato (MFEL). Participaram 14 adultos jovens fisicamente ativos (23±3,1 anos; 72±10,97 kg; 1,76±0,07 m; 21±5,36 % gordura corporal) que realizaram um teste de 3000m em pista para determinar o LAIind através de equação de predição; teste incremental em esteira ergométrica para determinação do LG; a VC foi identificada por regressão linear através da relação distância-tempo com base no desempenho em corridas nas distâncias de 3.000m e 500m; a MFEL foi identificada utilizando de dois a cinco testes em dias distintos até encontrar a intensidade onde não houve aumento da concentração de lactato sanguíneo maior que 1 mmol.L-1 entre os minutos 10 e 30. Houve diferença estatística entre os valores médios da VC e a MFEL (P≤0,05), elevada correlação entre MFEL e LAIind (R2=0,82; P≤0.01) e MFEL e LG (R2=0,72; P≤0.01). Através do método Bland-Altman foram encontradas as concordâncias entre MFEL e LAIind [diferença média -0,24 (intervalo de confiança -1,72 a 1,24) km/h] e MFEL e LG [0,21 (-1,26 a 1,29) km/h]. Concluímos que o LAIind e o LG são testes que podem predizer com boa precisão a velocidade da MFEL, tornando sua identificação prática e eficiente para prescrição de intensidades adequadas para o treinamento aeróbio.Universidade Federal de São Paulo (UNIFESP)Faculdade Anhanguera de BauruUniversidade Federal de São Paulo (UNIFESP) Departamento de Ciências do Movimento HumanoUNIFESP, Depto. de Ciências do Movimento HumanoSciEL

A VIRTUAL SIMULATOR AS A TOOL FOR TEACHING REFRACTOMETRY

Significance: Several educational technological innovations are developed with the purpose of contributing to the training of future optometrists and ophthalmologists. However, very little is available for teaching refractometry. EYE REFRACTION is a simulator mobile applications (App) that works as a fast, straightforward and interactive interface tool for teaching refractometry. Purpose: Develop novel mobile application software (EYE REFRACTION) as a tool for teaching refractometry in medical schools. Methods: EYE REFRACTION software was developed by the emerging company “Ciência Ilustrada studio” incubated at “INOVA Metrópole” of the Digital Metropolis Institute of the Universidade Federal do Rio Grande do Norte, Brazil (IMD-UFRN), using the XCode 4.6.2. program (Apple Computer, Inc. Cupertino, CA, USA). This application software (App) was created for Tablets and has a fully interactive workspace, where after inserting the refraction data of the patient, the user can observe points or focal lines of the refractive errors and all the arrangements resulting from the various possible corrections. Results: After 90 days of blind and random simulations of the EYE REFRACTION App performed by volunteered ophthalmologists, six failures were detected and promptly corrected. Two were detected when refractive errors were simulated (simple myopic astigmatism), two during simulations of hypermetropic astigmatism, being one simple and the other compound, and two others during the simulation of mixed astigmatism. Conclusion: A novel App for teaching refractometry was successfully developed, where it enabled a real-time observation of refractive errors and their arrangements. The EYE REFRACTION App is currently available at Apple App Store

Resistance training with slow speed of movement is better for hypertrophy and muscle strength gains than fast speed of movement.

Repetition speed is an important variable during resistance training. However, the effects of different speeds on the muscular strength and hypertrophy in isotonic resistance training are not clear. The study compared fast speed with slow speed of isotonic resistance training on muscular strength and hypertrophy in well-trained adults. Twelve healthy adults were randomly assigned into two groups: fast speed (FS) and low speed (SS). Muscle hypertrophy was measured by an ultrasound examination of the cross-sectional area of the brachial biceps muscle. Muscular strength was verified by 1 RM test. To check the possible differences in strength and hypertrophy between pre and post training and between groups there were compared by two-way ANOVA for repeated measurements and the effect size (ES) was calculated. Improvement in the cross-sectional area (P=0.019) and muscular strength (P=0.021) in the SS group between pre and post training was verified. The SS group had bigger effect sizes than FS group for hypertrophy and strength from pre to post training. SS training was more effective to improve hypertrophy and muscle strength in well-trained adults.Univ Fed Sao Paulo, Grp Studies & Res Exercise Physiol, Santos, SP, BrazilPraia Grande Coll, Grp Studies Sci Phys Educ, Praia Grande, SP, BrazilUniv Fed Sao Paulo, Dept Human Movement Sci, Santos, SP, BrazilUniv Fed Sao Paulo, Grp Studies & Res Exercise Physiol, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Human Movement Sci, Santos, SP, BrazilWeb of Scienc

mHealth in urology

Introduction: Smartphones are increasingly playing a role in healthcare and previous studies assessing medical applications (apps) have raised concerns about lack of expert involvement and low content accuracy. However, there are no such studies in Urology. We reviewed Urology apps with the aim of assessing the level of participation of healthcare professionals (HCP) and scientific Urology associations in their development. Material and Methods: A systematic search was performed on PubMed, Apple's App Store and Google's Play Store, for Urology apps, available in English. Apps were reviewed by three graders to determine the app's platform, target customer, developer, app type, app category, price and the participation of a HCP or a scientific Urology association in the development. Results: The search yielded 372 apps, of which 150 were specific for Urology. A fifth of all apps had no HCP involvement (20.7%) and only a third had been developed with a scientific Urology association (34.7%). The lowest percentage of HCP (13.4%) and urological association (1.9%) involvement was in apps designed for the general population. Furthermore, there was no contribution from an Urology society in "Electronic Medical Record" nor in "Patient Information" apps. A limitation of the study is that only Android and iOS apps were reviewed. Conclusions: Despite the increasing Mobile Health (mHealth) market, this is the first study that demonstrates the lack of expert participation in the design of Urology apps, particularly in apps designed for the general public. Until clear regulation is enforced, the urological community should help regulate app development. Maintaining a register of certified apps or issuing an official scientific seal of approval could improve overall app quality. We propose that urologists become stakeholders in mHealth, shaping future app design and promoting peer-review app validation

Eleições federais no Canadá

Polis. - ISSN 0872-8208. - S. 2, n. 4 (Julho-Dezembro 2021). - p. 207-210.O Canadá é uma monarquia constitucional parlamentar, atual membro da Commonwealth, tendo como Chefe de Estado a rainha Elizabeth II. O sistema político canadiano reflete, em geral, o legado britânico, à exceção do federalismo incorporado com o intuito de acomodar interesses regionais, em especial os da comunidade pioneira de origem francesa. A 44.ª eleição geral canadiana realizou-se a 20 de setembro de 2021, somente dois anos após o último ato eleitoral de 21 de outubro de 2019. De acordo com os resultados eleitorais apurados em 2019, o Partido Liberal de Justin Trudeau (Primeiro-Ministro desde 2015 e líder do Partido Liberal desde 2013) conseguiu 156 de um total de 338 deputados da Casa dos Comuns, ou seja, menos 14 do que aqueles que são necessários para governar sem precisar do apoio de outros grupos políticos. Em termos comparativos com as eleições de 2015, os liberais conquistaram 184 mandatos (perfazendo, então, a maioria absoluta), o que significa que passados quatro anos, em termos absolutos, perderam 28 lugares na Câmara dos Comuns, bem como a maioria absoluta

O acesso do negro à graduação em medicina como ferramenta antirracista uma revisão bibliográfica

This article discusses how access to graduation in medicine can be an anti-racist tool, considering the social structure that makes it difficult for black people to enter and remain in higher education. Thus, the objective of this work is to analyze the difficulty of access by the black population to the medical course. In this way, we use a qualitative bibliographic methodology and dialogue with authors who discuss and analyze the theme in question: (ALMEIDA, 2019), (SANTOS, 2003), (MBEMBE, 2014) among others. In this perspective, we conclude that although there are racial quota policies, demographic data from 2019 show that the black population still faces high rates of illiteracy, school dropout, low attendance in higher education, unemployment and dependence on the public health service. At a university in Rio de Janeiro, the majority of medical students are white, with an annual income of more than US$8,640, coming from a private school, with financial support from the family and both parents with higher education.  Este artigo discute como o acesso à graduação em medicina pode ser uma ferramenta antirracista, considerando a estrutura social que dificulta o ingresso e a permanência de negros no ensino superior. Assim, o objetivo deste trabalho é analisar a dificuldade de acesso da população negra no curso de medicina. Dessa forma, utilizamo-nos de uma metodologia qualitativa bibliográfica e dialogamos com autores que discutem e analisam a temática em questão: (ALMEIDA, 2019), (SANTOS, 2003), (MBEMBE, 2014) dentre outros. Nessa perspectiva, concluímos que, embora existam políticas de cotas raciais, dados demográficos de 2019 mostram que a população negra ainda enfrenta altos índices de analfabetismo, evasão escolar, baixa presença no ensino superior, desemprego e dependência do serviço público de saúde. Em uma universidade do Rio de Janeiro, o perfil majoritário dos estudantes de medicina é branco, com renda anual superior a US$ 8.640, proveniente de escola particular, com apoio financeiro da família e ambos os pais com ensino superior. Além disso, mesmo após mais de 10 anos da promulgação da Lei de Cotas, a presença de pessoas não brancas no curso ainda não aumentou significativamente. Embora tenham sido desenvolvidas medidas para tentar extinguir o racismo, tais medidas serviram como maquiagem, numa fracassada tentativa de esconder as falhas do sistema educacional, político e socioeconômico em lidar com a estrutura social excludente. &nbsp