Lack of Acute Agomelatine Effect in a Model of Social Anxiety in Healthy Volunteers: A Double-Blind, Placebo-Controlled Trial.

BACKGROUND: Agomelatine is an antidepressant drug that acts as an agonist of melatoninergic MT1/2 receptors and an antagonist of serotonergic 5-HT2C receptors. Studies suggest that agomelatine has anxiolytic properties in social anxiety, but there are no studies that assessed the effects of this compound in human experimental anxiety induced by a public speaking test. The objective of our investigation was to assess the effects of agomelatine on human experimental anxiety using the Simulation Public Speaking Test (SPST). METHODS: Agomelatine (25 mg, n = 14), citalopram (20 mg, n = 14), venlafaxine (75 mg, n = 14), or placebo (n = 14) were administered in single doses to healthy volunteers in a double-blind study. Subjective anxiety was assessed with the Visual Analogue Mood Scale. Arterial blood pressure, heart rate, and blood levels of prolactin and cortisol were also recorded, as well as plasma levels of the 3 drugs. RESULTS: The SPST induced significant subjective, physiological, and hormonal effects in all groups. The SPST also increased the anxiety and decreased mental sedation Visual Analogue Mood Scale factors during the anticipatory and performance phases of the test. Citalopram increased anxiety during the test in females, whereas agomelatine and venlafaxine were not different from placebo. CONCLUSIONS: Confirming previous results, a serotonin selective reuptake inhibitor, citalopram, caused an anxiogenic effect in the SPST only in females. Acute administration of a low dose of agomelatine failed to modify the behavioral and physiological changes caused by this test. Future studies using higher doses and repeated administration should investigate if agomelatine behavioral and physiological effects could be detected in human experimental anxiety models.

Bacterial cellulose nanocrystals obtained through enzymatic and acidic routes: A comparative study of their main properties and in vitro biological responses.

Cellulose nanocrystals (CNCs) are crystalline domains isolated from cellulosic fibers. They have been utilized in a wide range of applications, such as reinforcing fillers, antibacterial agents and manufacturing of biosensors. Whitin this context, the aim of this work was to obtain and analyze CNCs extracted from bacterial nanocellulose (BNC) using two distinct methods combined with milling pre-treatment: an acidic hydrolysis using 64 % sulfuric acid and an enzymatic hydrolysis using a commercial cellulase enzyme mixture. The CNCs obtained from the enzymatic route (e-CNCs) were observed to be spherical nanoparticles with diameter of 56 ± 11 nm. In contrast, the CNCs from the acid hydrolysis (a-CNCs) appeared as needle-shaped nanoparticles with a high aspect ratio with lengths/widths of 158 ± 64 nm/11 ± 2 nm. The surface zeta potential (ZP) of the a-CNCs was -30,8 mV, whereas the e-CNCs has a potential of +2.70 ± 3.32 mV, indicating that a-CNCs consisted of negatively charged particles with higher stability in solution. Although the acidic route resulted in nanocrystals with a slightly higher crystallinity index compared to the enzymatic route, e-CNCs was found to be more thermally stable than BNC and a-CNCs. Here, we also confirmed the safety of a-CNCs and e-CNCs using L929 cell line. Lastly, this article describes two different CNCs synthesis approaches that leads to the formation of nanoparticles with different dimensions, morphology and unique physicochemical properties. To the best of our knowledge, this is the first study to yield spherical nanoparticles as a result of BNC enzymatic treatment.

Sex differences in the anticompulsive-like effect of memantine: Involvement of nitric oxide pathway but not AMPA receptors.

Memantine, an N-Methyl-D-Aspartate (NMDA) antagonist, has been examined as a potential treatment for Obsessive-Compulsive Disorder (OCD). Yet, there is limited knowledge regarding how it works to reduce compulsive behaviour and whether it has different effects on individuals based on their sex. Herein, we investigated if there are sex differences in the anticompulsive-like effect of memantine in adult Swiss mice. Additionally, we explored whether the nitric oxide (NO) pathway and α-amino-3-hydroxy-5-methyl-4-isoazolepropionic acid (AMPA) receptors play a role in memantine's effects. To start, we assessed the impact of a single intraperitoneal dose of memantine (at 3, 5, and 10 mg/kg) on behaviours exhibited in the open field test (OFT) and the marble-burying test (MBT), the latter being a predictive test for anticompulsive effects. All doses of memantine reduced marble-burying behaviour in both male and female mice without affecting their locomotor activity in the OFT. This anticompulsive-like effect was also confirmed in another predictive test, the nest-building test, with the highest memantine dose (10 mg/kg) reducing nest-building behaviour without significant differences between male and female mice. We observed that pre-treatment with L-arginine, a NO precursor, mitigated the anticompulsive-like effect of memantine in male mice but had no effect in female mice in the MBT. Finally, NBQX, an AMPA receptor antagonist, did not block the anticompulsive-like effect of memantine. In summary, our study suggests that the anticompulsive-like effect of memantine does not appear to be sex-specific, does not depend on AMPA receptors, and involves the NO pathway primarily in male mice.

Comportamento preventivo contra covid-19 e sua relação com as condições sociais e de saúde de pessoas idosas / Preventive behavior against covid-19 and its relationship with the social and health conditions of older adults

Resumo Objetivo Descrever o perfil de comportamento preventivo contra covid-19 adotado pelas pessoas idosas e verificar sua relação com as condições sociais e de saúde. Método Estudo transversal e analítico realizado com 72 indivíduos (≥ 60 anos) cadastrados em uma Universidade Aberta para Pessoas Idosas, no município de Campinas, São Paulo, Brasil. Os participantes foram contatados por meio de ligações telefônicas, no período de novembro de 2020 a junho de 2021. Um total de 11 medidas preventivas foram analisadas para a identificação dos comportamentos adotados pelas pessoas idosas contra covid-19. Para a análise dos dados, utilizaram-se análise de componentes principais, testes qui-quadrado de Pearson e Exato de Fisher, com 95% de confiança. Resultados A adoção de comportamentos preventivos foi avaliada por meio das atividades de: higienização das mãos com água e sabão, uso do álcool em gel, uso de máscara facial e distanciamento social. A maioria dos indivíduos mencionou a adoção de comportamentos preventivos (79,2%), e verificou-se que aqueles com renda inferior a quatro salários-mínimos apresentaram maiores proporções de comportamento (87,5%) quando comparados aos indivíduos de renda superior a 10 salários-mínimos (46,2%) (p=0,038). Conclusão Houve adoção às medidas preventivas para covid-19 pelos idosos, influenciada pela renda. Os achados ressaltam a importância de estratégias educativas para promoção de comportamentos preventivos em saúde, considerando o contexto social.

Abstract Objective To delineate the profile of preventive behavior against covid-19 adopted by older adults and investigate its correlation with social and health conditions. Method A cross-sectional and analytical study conducted with 72 individuals (≥ 60 years) enrolled in an Open University for Older Adults in the municipality of Campinas, São Paulo, Brazil. Participants were contacted via telephone from November 2020 to June 2021. A total of 11 preventive measures were scrutinized to identify the behaviors adopted by older adults against covid-19. Data analysis employed principal component analysis, Pearson's chi-square tests, and Fisher's exact tests, with a confidence level of 95%. Results The adoption of preventive behaviors was assessed through activities such as hand hygiene with soap and water, use of hand sanitizer, wearing facial masks, and practicing social distancing. The majority of individuals reported the adoption of preventive behaviors (79.2%), and it was observed that those with incomes below four minimum wages exhibited higher proportions of compliance (87.5%) compared to individuals with incomes exceeding 10 minimum wages (46.2%) (p=0.038). Conclusion Preventive measures against covid-19 were embraced by the older adults, influenced by income. The findings underscore the significance of educational strategies for fostering health preventive behaviors, taking into account the social context.

The emergence of hybrid cellulose nanomaterials as promising biomaterials.

Cellulose nanomaterials (CNs) are promising green materials due to their unique properties as well as their environmental benefits. Among these materials, cellulose nanofibrils (CNFs) and nanocrystals (CNCs) are the most extensively researched types of CNs. While they share some fundamental properties like low density, biodegradability, biocompatibility, and low toxicity, they also possess unique differentiating characteristics such as morphology, rheology, aspect ratio, crystallinity, mechanical and optical properties. Therefore, numerous comparative studies have been conducted, and recently, various studies have reported the synergetic advantages resulting from combining CNF and CNC. In this review, we initiate by addressing the terminology used to describe combinations of these and other types of CNs, proposing "hybrid cellulose nanomaterials" (HCNs) as the standardized classifictation for these materials. Subsequently, we briefly cover aspects of properties-driven applications and the performance of CNs, from both an individual and comparative perspective. Next, we comprehensively examine the potential of HCN-based materials, highlighting their performance for various applications. In conclusion, HCNs have demonstraded remarkable success in diverse areas, such as food packaging, electronic devices, 3D printing, biomedical and other fields, resulting in materials with superior performance when compared to neat CNF or CNC. Therefore, HCNs exhibit great potential for the development of environmentally friendly materials with enhanced properties.

High-yield production of rod-like and spherical nanocellulose by controlled enzymatic hydrolysis of mechanically pretreated cellulose.

In this study, a simple and scalable mechanical pretreatment was evaluated as means of enhancing the accessibility of cellulose fibers, with the objective of improving the efficiency of enzymatic reactions for the production of cellulose nanoparticles (CNs). In addition, the effects of enzyme type (endoglucanase - EG, endoxylanase - EX, and a cellulase preparation - CB), composition ratio (0-200UEG:0-200UEX or EG, EX, and CB alone), and loading (0 U-200 U) were investigated in relation to CN yield, morphology, and properties. The combination of mechanical pretreatment and specific enzymatic hydrolysis conditions substantially improved CN production yield, reaching up to 83 %. The production of rod-like or spherical nanoparticles and their chemical composition were highly influenced by the enzyme type, composition ratio, and loading. However, these enzymatic conditions had minimal impact on the crystallinity index (approximately 80 %) and thermal stability (Tmax within 330-355 °C). Overall, these findings demonstrate that mechanical pretreatment followed by enzymatic hydrolysis under specific conditions is a suitable method to produce nanocellulose with high yield and adjustable properties such as purity, rod-like or spherical forms, high thermal stability, and high crystallinity. Therefore, this production approach shows promise in producing tailored CNs with the potential for superior performance in various advanced applications, including, but not limited to, wound dressings, drug delivery, thermoplastic composites, 3D (bio)printing, and smart packaging.

Actinomycosis in the maxilla of a young asymptomatic patient: unusual case report / Actinomicose em maxila de um paciente jovem assintomático: relato de caso incomum

ABSTRACT The aim of this study is to report an unusual case of actinomycosis in the maxilla region of an asymptomatic patient. A 21-year-old white man was referred for the analysis of panoramic radiography and cone beam computed tomography, where it was observed the presence of a hypodense lesion on the left side of the maxilla, which extended from the maxillary left central incisor to the region of the maxillary left second premolar. During intraoral examination, a depression was observed in the hard palate mucosa, as well as a fistula in the alveolar mucosa close to maxillary left central incisor, which had pulp vitality confirmed by thermal tests. A fistulography was performed, with periapical radiography, where it was found that the fistulous path did not originate from the tooth mentioned above. An incisional biopsy was performed for diagnostic purposes. However, given the inconclusive microscopic findings, four months later, a new biopsy was performed. The histopathological examination revealed the presence of a colony of microoganisms with filamentous pattern of radiated rosette, surrounded by polymorphonuclear inflammatory cells. Based on the morphological characteristics, the diagnosis of actinomycosis was established. The treatment was based on antibiotic therapy. Six months after treatment of the infection, no signs of recurrence were observed, and the patient remains in follow-up. Actinomycosis in the maxilla is an uncommon infection with a predilection for males between the ages of 20 and 60, whose treatment is antibiotic therapy associated or not with surgical excision.

RESUMO O objetivo deste estudo é relatar um caso incomum de actinomicose em região de maxila de um paciente assintomático. Um homem de 21 anos, branco, foi encaminhado para análise de radiografia panorâmica e tomografia computadorizada de feixe cônico, onde foi observada a presença de lesão hipodensa do lado esquerdo da maxila, que se estendia da região do incisivo central superior esquerdo ao segundo pré-molar superior esquerdo. Ao exame intrabucal, observou-se depressão na mucosa do palato duro, bem como fístula na mucosa alveolar próxima ao incisivo central superior esquerdo, no qual tinha vitalidade pulpar confirmada pelos testes térmicos. Uma fistulografia com radiografia periapical foi realizada, onde foi observado que o trajeto fistuloso não era originado do dente mencionado anteriormente. Foi realizada biópsia incisional para fins diagnósticos. Porém, diante dos achados microscópicos inconclusivos, quatro meses depois, uma nova biópsia foi realizada. O exame histopatológico revelou a presença de colônia de microrganismos com padrão filamentoso de roseta irradiada, circundado por células inflamatórias polimorfonucleares. Com base nas características morfológicas, foi estabelecido o diagnóstico de actinomicose. O tratamento foi baseado em antibioticoterapia. Seis meses após o tratamento da infecção, não foram observados sinais de recidiva e o paciente permanece em acompanhamento. A actinomicose da maxila é uma infecção incomum, com predileção por pacientes do sexo masculino com idade entre 20 e 60 anos, cujo tratamento é antibioticoterapia associada ou não à excisão cirúrgica.

Xylanase increases the selectivity of the enzymatic hydrolysis with endoglucanase to produce cellulose nanocrystals with improved properties.

Enzyme-mediated isolation of cellulose nanocrystals (CNCs) is a promising environment friendly method with expected lower capital and operating expenditures compared to traditional processes. However, it is still poorly understood. In this study, an endoxylanase was applied as accessory enzyme to assess its potential to increase the selectivity of an endoglucanase during cellulose hydrolysis to isolate CNCs with improved properties. Only combinations of the enzymes with xylanase activity equal to or higher than the endoglucanase activity resulted in CNCs with improved properties (i.e., crystallinity, thermostability, uniformity, suspension stability and aspect ratio). The beneficial effects of the accessory enzyme are related to its hydrolytic (xylan and cellulose hydrolysis) and non-hydrolytic action (swelling of cellulose fibers and fiber porosity) and on the ratio of the enzymes, which in turn allows to tailor the properties of the CNCs. In conclusion, compared to the traditional sulfuric acid hydrolysis method, accessory enzymes help to isolate cellulose nanomaterials with improved and customized (sizes, aspect ratio and morphology) properties that may allow for new applications.

Common mental disorders among medical students: systematic review and meta-analysis of Brazilian studies.

BACKGROUND: Common mental disorders (CMDs) have been correlated with consequences in different domains of life. OBJECTIVE: To summarize the prevalence rates of CMDs and factors associated with them among students at Brazilian medical schools. DESIGN AND SETTING: Systematic review and meta-analysis of studies developed in Brazilian medical schools. METHODS: In October 2021, searches were carried out in seven electronic databases, in Google Scholar and in reference lists. Observational studies reporting prevalence rates of CMDs among students at Brazilian medical schools were sought. Variables associated with CMDs arising from multivariate regression models were included in the synthesis. A meta-analysis was developed using a random-effects model and the risk of bias was assessed using an instrument developed from previous references. RESULTS: Fourteen original studies were included. The pooled prevalence rate of CMDs among undergraduate students at Brazilian medical schools was 43.3% (95% confidence interval = 38.9% to 47.6%; I2 = 87%; n = 3,927). Among the nine studies in which multivariate analyses were conducted, five showed risk associations between CMDs and medical school-related dissatisfactions, among which the desire to abandon the medical course can be highlighted (n = 3). In three studies, CMDs were associated with sleep indicators. CONCLUSION: Considering that the prevalence of CMDs among medical students is higher than in the general population, we recommend that Brazilian medical schools should give greater attention to this topic, and should enable expansion of care offerings relating to mental health. SYSTEMATIC REVIEW REGISTRATION: Prospective Register of Systematic Reviews (PROSPERO) database (CRD42020142184).

Common mental disorders among medical students: systematic review and meta-analysis of Brazilian studies

ABSTRACT BACKGROUND: Common mental disorders (CMDs) have been correlated with consequences in different domains of life. OBJECTIVE: To summarize the prevalence rates of CMDs and factors associated with them among students at Brazilian medical schools. DESIGN AND SETTING: Systematic review and meta-analysis of studies developed in Brazilian medical schools. METHODS: In October 2021, searches were carried out in seven electronic databases, in Google Scholar and in reference lists. Observational studies reporting prevalence rates of CMDs among students at Brazilian medical schools were sought. Variables associated with CMDs arising from multivariate regression models were included in the synthesis. A meta-analysis was developed using a random-effects model and the risk of bias was assessed using an instrument developed from previous references. RESULTS: Fourteen original studies were included. The pooled prevalence rate of CMDs among undergraduate students at Brazilian medical schools was 43.3% (95% confidence interval = 38.9% to 47.6%; I2 = 87%; n = 3,927). Among the nine studies in which multivariate analyses were conducted, five showed risk associations between CMDs and medical school-related dissatisfactions, among which the desire to abandon the medical course can be highlighted (n = 3). In three studies, CMDs were associated with sleep indicators. CONCLUSION: Considering that the prevalence of CMDs among medical students is higher than in the general population, we recommend that Brazilian medical schools should give greater attention to this topic, and should enable expansion of care offerings relating to mental health. SYSTEMATIC REVIEW REGISTRATION: Prospective Register of Systematic Reviews (PROSPERO) database (CRD42020142184).

Ayahuasca, a potentially rapid acting antidepressant: focus on safety and tolerability.

INTRODUCTION: Ayahuasca is a psychedelic brew originally used by Amazonian indigenous groups and in religious rituals. Pre-clinical and observational studies have demonstrated its possible potential as an antidepressant, and open- and placebo-controlled clinical trials corroborated these results. For it to become an approved treatment for depression, its safety and tolerability need to be assessed and documented. AREAS COVERED: We have gathered data regarding the occurrence of adverse events (AEs) in all reported randomized, placebo-controlled trials with healthy and clinical populations involving ayahuasca administration (n = 108 ayahuasca administrations). We systematically categorized these results, recorded their prevalence, and discussed the possible mechanisms related to their emergence. EXPERT OPINION: There were no reports of serious AEs, indicating a relative safety of ayahuasca administration in controlled settings. Most common AEs included nausea, vomiting, headaches, and transient increases in cardiovascular measurements. Ayahuasca research is still in its infancy, especially concerning the absence of large and robust clinical trials to verify its antidepressant effects. Dose standardization, legal prohibition of the possession of its alkaloids and how traditional communities will be compensated if ayahuasca becomes an approved medicine are the biggest obstacles to overcome for its future use in the therapeutic context.

Effect of two oral formulations of cannabidiol on responses to emotional stimuli in healthy human volunteers: pharmaceutical vehicle matters

Objective: To compare plasma concentrations of cannabidiol (CBD) following oral administration of two formulations of the drug (powder and dissolved in oil), and to evaluate the effects of these distinct formulations on responses to emotional stimuli in healthy human volunteers. Methods: In a randomized, double-blind, placebo-controlled, parallel-group design, 45 healthy male volunteers were randomly assigned to three groups of 15 subjects that received either 150 mg of CBD powder; 150 mg of CBD dissolved in corn oil; or placebo. Blood samples were collected at different times after administration, and a facial emotion recognition task was completed after 150 min. Results: There were no significant differences across groups in the subjective and physiological measures, nor in the facial emotion recognition task. However, groups that received the drug showed statistically significant differences in baseline measures of plasma CBD, with a significantly greater difference in favor of the oil formulation. Conclusion: When administered as a single 150-mg dose, neither formulation of oral CBD altered responses to emotional stimuli in healthy subjects. The oil-based CBD formulation resulted in more rapid achievement of peak plasma level, with an approximate fourfold increase in oral bioavailability.

An overview of the molecular and physiological antidepressant mechanisms of physical exercise in animal models of depression.

BACKGROUND: Depression is a global disease that affects the physical and mental health of people of all ages. Non-pharmacological and unconventional methods of treatment, such as regular physical exercise, have been recommended to treat depression. METHODS: Here, we briefly review the literature about the physiological and molecular mechanisms of exercise antidepressants in depressive-like behavior in animal models of depression. RESULTS: The main hysiological and molecular mechanisms of physical exercise in depression include blood flow changes in several areas of the brain, increase in brain serotonin synthesis, increase in antioxidant enzymes, increase in serum and brain brain-derived neuro factor (BDNF) levels, decrease in cortisol levels and reduced inflammation in peripheral and brain tissues. Physical exercise also leads to increased activation of the phosphatidylinositol-3-kinase (PI3K), PGC-1α/FNDC5/Irisin pathway, BDNF concentrations (serum and cerebral), extracellular signal-regulated kinase and cAMP-response element binding protein (mainly in neurons of the hippocampus and prefrontal cortex), which together contribute to fight or inhibit the development of depression symptoms. These molecular and physiological mechanisms work in synchrony, further enhancing their effects. CONCLUSION: Physical exercise can be used as a safe and effective non-pharmacological treatment in depression.

Effect of two oral formulations of cannabidiol on responses to emotional stimuli in healthy human volunteers: pharmaceutical vehicle matters.

OBJECTIVE: To compare plasma concentrations of cannabidiol (CBD) following oral administration of two formulations of the drug (powder and dissolved in oil), and to evaluate the effects of these distinct formulations on responses to emotional stimuli in healthy human volunteers. METHODS: In a randomized, double-blind, placebo-controlled, parallel-group design, 45 healthy male volunteers were randomly assigned to three groups of 15 subjects that received either 150 mg of CBD powder; 150 mg of CBD dissolved in corn oil; or placebo. Blood samples were collected at different times after administration, and a facial emotion recognition task was completed after 150 min. RESULTS: There were no significant differences across groups in the subjective and physiological measures, nor in the facial emotion recognition task. However, groups that received the drug showed statistically significant differences in baseline measures of plasma CBD, with a significantly greater difference in favor of the oil formulation. CONCLUSION: When administered as a single 150-mg dose, neither formulation of oral CBD altered responses to emotional stimuli in healthy subjects. The oil-based CBD formulation resulted in more rapid achievement of peak plasma level, with an approximate fourfold increase in oral bioavailability.

Soybean meal particle size for pigs during the nursery phase / Tamanho da partícula do farelo de soja em suínos no período de creche

This study evaluated the effect of soybean meal (SBM) particle size on nutrient digestibility and the growth performance of nursery piglets. Sixty-three piglets (BW = 6.86 kg ± 0.56; 23 d of age) were distributed in a randomized block design (by initial weight and sex) with 3 dietary treatments: diets with 1,017 µm (unground); 585 µm; and 411µm SBM, with 7 replicates of 3 piglets each. All diets were offered ad libitum in mash form, formulated differently according to three growing phases: (1) with 20% of SBM, from 23 to 32 d of age; (2) with 25% of SBM, from 32 to 44 d of age, and (3) with 30% of SBM, from 44 to 63 d of age. For the first 21 d, pigs fed diets with a medium particle size of SBM (585mm) had better average weight gain and feed/gain ratio (P<0.05). The average feed intake, average body weight gain, and feed/gain ratio from 44 to 63 d improved (P<0.05) with increasing SBM particle sizes, and the average live weight for the overall period increased with coarser SBM (P<0.05). There was a marginally improvement (P < 0.1) on digestible energy as particle size of SBM decreased; although, no differences (P > 0.05) in the coefficients of apparent digestibility of dry matter and crude protein for the assessed SBM particle sizes were observed. It was concluded that the grinding of dietary SBM is not required for piglets during the nursery phase.

O objetivo deste estudo foi avaliar o efeito do tamanho da partícula do farelo de soja (FS) sobre o desempenho e digestibilidade de leitões no período de creche. 63 leitões (6,86 kg ± 0,56; 23 dias de idade) foram distribuídos aleatoriamente em um delineamento de blocos casualizados (peso inicial e sexo) entre os tratamentos. As dietas experimentais foram produzidas a partir de diferentes tamanhos médios de partículas do FS moídos ou não: 1,017 µm (sem moer), 585 µm (moído em peneira de 10 mm), e 411µm (moído em peneira de 3 mm), totalizando três tratamentos com sete repetições de três animais cada. Todas as dietas foram fornecidas na forma farelada e ad libitum, sendo divididas em três fases: 1) com 20% de FS, dos 23 a 32 dias de idade; 2) com 25% de FS, dos 32 a 44 dias de idade; e 3) com 30% de FS, dos 44 a 62 dias de idade. Nos primeiros 21 dias de experimento, os animais consumindo a dieta com o tamanho médio (585 µm) das partículas do FS apresentaram melhores resultados para o ganho de peso médio e conversão alimentar. No período seguinte (44 a 63 d), houve (P<0.05) aumento do consumo de ração médio, do ganho do peso médio e melhor conversão alimentar dos leitões conforme o aumento do tamanho da partícula de FS incluída na ração. Consequentemente, ao final do experimento houve melhora linear do peso vivo médio dos animais com o aumento do tamanho do FS consumido. Foi observado melhora marginalmente significativa (P < 0.1) da energia digestível conforme a redução no tamanho do FS, entretanto, não houve diferença (P > 0.05) no coeficiente de digestibilidade aparente da matéria seca e da proteína bruta dos animais entre os diferentes tamanhos do FS. Em conclusão, de acordo com as condições deste estudo, não se faz necessária a moagem do farelo de soja para leitões no período de creche.

Involvement of dopamine D2 and glutamate NMDA receptors in the antidepressant-like effect of amantadine in mice.

The present study investigated the pharmacological mechanisms of the antidepressant-like effects of amantadine in mice and their influence on hippocampal neurogenesis. To improve the translational validity of preclinical results, reproducibility across laboratories and replication in other animal models and species are crucial. Single amantadine administration at doses of 50 and 75 mg/kg resulted in antidepressant-like effects in mice in the tail suspension test (TST), reflected by an increase in immobility time. The effects of amantadine were seen at doses that did not alter locomotor activity. The tyrosine hydroxylase inhibitor α-methyl-ρ-tyrosine did not influence the anti-immobility effect of amantadine in the TST. Pretreatment with the α1 adrenergic receptor antagonist prazosin, ß adrenergic receptor antagonist propranolol, α2 adrenergic receptor antagonist yohimbine, and α2 adrenergic receptor agonist clonidine did not alter the antidepressant-like effect of amantadine. However, amantadine's effect was blocked by the dopamine D2 receptor antagonist haloperidol and glutamate receptor agonist N-methyl-D-aspartate (NMDA). Repeated amantadine administration (50 mg/kg) also exerted an antidepressant-like effect, paralleled by an increase in hippocampal neurogenesis. The present results demonstrate that the antidepressant-like effects of amantadine may be mediated by its actions on D2 and NMDA receptors and likely involve hippocampal neurogenesis.

Rating of Perceived Exertion in Three-Minute Step Test in Children with Cystic Fibrosis.

The purpose of the study was to assess whether there are differences in cardiorespiratory fitness between children with and without cystic fibrosis (CF). Ten children with CF attended at a referral center for the treatment of CF and 13 children without CF were evaluated. The average age of the children with CF was 10.40 (3.13) years and those without CF was 9.39 (3.25) years. The children performed the three-minute step test with monitoring of hemodynamic parameters and the rating of perceived exertion (RPE) every minute. Oxygen desaturation of 4% during the test occurred in three children with CF and none of the children reached a SatO2 percentage < 75%. After the step test, the findings showed that children with CF presented higher RPE scores during the test (p = 0.002) when compared to children without CF (p < 0.001). The RPE was the only parameter that changed during the test and demonstrated that children with cystic fibrosis tired more during the test when compared to children without CF despite the lack of changes in hemodynamic variables.

Molecular mechanisms of physical exercise on depression in the elderly: a systematic review.

Depressive disorders are common among the elderly. Major depressive disorder will be one of the highest healthcare costs in middle and higher income countries by 2030. It is known that physical inactivity leads to negative effects on mental health in the elderly.The purpose of this review was to explore investigate the consequences of physical exercise (aerobic and resistance exercise) on major depressive disorder among elderly, and presenting its potential biological mechanisms. This study was designed according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Clinical trials or randomized clinical trials or cohort studies participated of the study design. Ten studies were evaluated and the main outcomes of each were reported. Aerobic and resistance training revealed to be effective in fighting the symptoms of depression. The most common physical exercise protocol adopted to reduce the consequences of major depressive disorder in humans was the prescription of aerobic exercise at moderate-intensity lasting 60 min per session, 3 times per week, for 24 weeks. Physical exercise enhances IGF-I and activates PGC-1α/FNDC5/Irisin pathway. Physical exercise also increases expression of BDNF and its receptor, TrkB, in the hippocampus and prefrontal cortex leading to upstream of ERK and inhibiting depressive-like behavior. Physical exercise brings mental health benefits and plays a crucial role in avoiding the development of major depressive disorder.