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Western equine encephalitis virus (WEEV) is a mosquitoborne alphavirus that causes central nervous system (CNS) infection in humans and equids in the United States, Canada, and the southern cone of [...]

Abstract Programmed-cell death is an antimicrobial defense mechanism that promotes clearance of intracellular pathogens. Toxoplasma counteracts host immune defenses by secreting effector proteins into host cells; however, how the parasite evades lytic cell death and the effectors involved remain poorly characterized. We identified ROP55, a rhoptry protein that promotes parasite survival by preventing lytic cell death in absence of IFN-γ stimulation. RNA-Seq analysis revealed that ROP55 acts as a repressor of host pro-inflammatory responses. In THP-1 monocytes ΔROP55 infection increased NF-κB p65 nuclear translocation, IL-1β production, and GSDMD cleavage compared to wild type or complemented parasites. ΔROP55 infection also induced RIPK3-dependent necroptosis in human and mouse primary macrophages. Moreover, ΔROP55 parasites were significantly impaired in virulence in female mice and prevented NF-κB activation and parasite clearance in mBMDM. These findings place ROP55 as a major virulence factor, dampening lytic cell death and enabling Toxoplasma to evade clearance from infected cells.

The inflammatory response to wear particles derived from hip prothesis is considered a hallmark of periprosthetic osteolysis, which can ultimately lead to the need for revision surgery. Exosomes (Exos) have been associated with various bone pathologies, and there is increasing recognition in the literature that they actively transport molecules throughout the body. The role of wear particles in osteoblast-derived Exos is unknown, and the potential contribution of Exos to osteoimmune communication and periprosthetic osteolysis niche is still in its infancy. Given this, we investigate how titanium dioxide nanoparticles (TiO2 NPs), similar in size and composition to prosthetic wear particles, affect Exos biogenesis. Two osteoblastic cell models commonly used to study the response of osteoblasts to wear particles were selected as a proof of concept. The contribution of Exos to periprosthetic osteolysis was assessed by functional assays in which primary human macrophages were stimulated with bone-derived Exos. We demonstrated that TiO2 NPs enter multivesicular bodies, the nascent of Exos, altering osteoblast-derived Exos secretion and molecular cargo. No significant differences were observed in Exos morphology and size. However, functional assays reveal that Exos cargo enriched in uPA stimulates macrophages to a mixed M1 and M2 phenotype, inducing the release of pro- and anti-inflammatory signals characteristic of periprosthetic osteolysis. In addition, we demonstrated the expression of uPA in exosomes derived from the urine of patients with osteolysis. These results suggest that uPA can be a potential biomarker of osteolysis. In the future, uPa may serve as a possible non-invasive biomarker to identify patients at risk for peri-implant osteolysis.

ABSTRACT: The objective of this research was to extract lignin from Eucalyptus sp. kraft black liquor and to evaluate the influence of its addition on the properties of the lignin-phenol-formaldehyde adhesive. The adhesives were synthesized at different phenol mass percentages by lignin, called lignin-phenol-formaldehyde adhesives in the proportions of 25, 30, 50, 75 and 80%. The parameters evaluated in the adhesives were pH, total solid content, organic compound content, inorganic compound content, gelatinization time and adhesive behavior in the glue line. The pH ranged from 10.63 to 11.65. For the total solid content was found the value of 53 to 69 %. The contents of organic compounds ranged from 51 to 75% and inorganic from 25 to 49%. It was observed that with the addition of macromolecule in the adhesive formulation, the total and organic solid content was reduced proportionally while the inorganic solid was high. The gelatinization time was reduced due to the addition of lignin. The lower proportions of addition presented better penetration and fluidity in interface with the wood. The kraft lignin extracted from eucalyptus kraft black liquor is a great adhesive with potential to partially replace petroleum-derived phenol, with great potential for use and application in the aeronautical and automotive sectors, in the bonding process of structural parts.

O presente artigo apresenta os resultados de uma Revisão Sistemática de Literatura (RSL) sobre o Arduino no ensino de física, utilizando artigos científicos indexados nas plataformas CAPES, SciELO e Redalyc, no período de 2018 a 2023. O objetivo desta pesquisa foi conduzir uma análise crítica da contribuição dos estudos na área acadêmica e científica no contexto nacional. Foram adotados procedimentos de pesquisa qualitativa, fundamentados nos conceitos técnicos e científicos da RSL, com processos e dados apresentados em quadros e gráficos. Os estudos analisados evidenciaram contribuições significativas no uso de equipamentos digitais em abordagens experimentais, destacando-se pela utilização de materiais de baixo custo. No entanto, foi observada uma baixa incidência da robótica educacional como estratégia de ensino nesta amostra. Espera-se que este estudo contribua para o campo acadêmico e científico, auxiliando professores e pesquisadores acerca das estratégias de ensino envolvendo Arduino e o ensino de física.

Leishmania is a trypanosomatid parasite that causes skin lesions in its cutaneous form. Current therapies rely on old and expensive drugs, against which the parasites have acquired considerable resistance. Trypanosomatids are unable to synthesize purines relying on salvaging from the host, and nucleoside analogues have emerged as attractive antiparasitic drug candidates. 4-Methyl-7-β-D-ribofuranosyl-7H-pyrrolo[2,3-d]pyrimidine (CL5564), an analogue of tubercidin in which the amine has been replaced by a methyl group, demonstrates activity against Trypanosoma cruzi and Leishmania infantum. Herein, we investigated its in vitro and in vivo activity against L. amazonensis. CL5564 was 6.5-fold (P = 0.0002) more potent than milteforan™ (ML) against intracellular forms in peritoneal mouse macrophages, and highly selective, while combination with ML gave an additive effect. These results stimulated us to study the activity of CL5564 in mouse model of cutaneous Leishmania infection. BALB/c female and male mice infected by L. amazonensis treated with CL5564 (10 mg kg−1, intralesional route for five days) presented a >93% reduction of paw lesion size likely ML given orally at 40 mg kg−1, while the combination (10 + 40 mg kg−1 of CL5564 and ML, respectively) caused >96% reduction. The qPCR confirmed the suppression of parasite load, but only the combination approach reached 66% of parasitological cure. These results support additional studies with nucleoside derivatives.

Introdução: A doença pulmonar obstrutiva crónica (DPOC) é a terceira causa de mortalidade a nível global. O tratamento foca-se na melhoria da qualidade de vida, atraso da progressão da doença e redução das exacerbações. Neste contexto, o benefício da reabilitação respiratória tem vindo a ser verificado. Esta medida não farmacológica pode ser implementada na comunidade, no contexto dos cuidados de saúde primários. Objetivos: Esta revisão sistemática propôs-se a fazer um levantamento da evidência atual sobre o impacto da reabilitação pulmonar na qualidade de vida dos doentes com DPOC, num contexto de cuidados de saúde primários. Métodos: Foram pesquisados estudos randomizados controlados em três bases de dados. Foi incluída a reabilitação pulmonar realizada na comunidade e excluídas intervenções em contexto hospitalar. Foi considerado como resultado primário a qualidade de vida relacionada com a saúde comparando com a terapêutica padrão da DPOC. A extração e triagem de dados foi efetuada por três autores, de forma independente. Avaliou-se o viés pela Cochrane Risk of Bias Tool. Resultados: Quatro estudos corresponderam aos critérios de pesquisa. Três estudos reportaram benefício em pelo menos um dos resultados. A frequência e duração da reabilitação pareceram ter algum impacto nos resultados. A mortalidade foi mais alta nos grupos de controlo. Os estudos incluídos tinham limitações importantes, nomeadamente a incapacidade de realizar intervenções cegas. Conclusões: A reabilitação pulmonar em cuidados de saúde primários melhora a qualidade de vida e capacidade funcional na DPOC. A duração, frequência e modalidade ótimas da intervenção não estão definidas e poderão depender de características individuais. Embora o paradigma não se altere, espera-se que esta revisão fomente o interesse na intervenção.

A figura do diretor técnico foi introduzida na lei em 2012, mas pouca investigação foi produzida para compreender como tem desenvolvido a sua ação. Este estudo pretendeu analisar as perceções dos técnicos de exercício físico (TEF) sobre i) a importância das funções dos diretores técnicos (tal como definidas na lei), e ii) a forma como os diretores técnicos cumprem e desenvolvem as suas funções, contrastando os resultados por segmento de mercado. Realizou-se uma análise descritiva e de frequências a uma amostra de 194 profissionais de exercício com uma média de idades de 34.46 anos (DP = 8.78), e com uma média de anos de experiência de 9.04 anos (DP = 6.84), que participaram voluntariamente neste estudo. O presente trabalho evidenciou que os TEF valorizam as funções atribuídas ao diretor técnico expressas na lei. Verificou-se que a regularidade do apoio do diretor técnico é bastante heterogénea, sendo que em quase 50% dos respondentes a classificação atribuída foi de inexistente ou pouco regular. Verificou-se ainda que cerca de 45% dos TEF consideraram a prestação dos diretores técnicos como sendo muito fraca ou fraca. Da análise por segmento de mercado, o low cost apresentou, genericamente, os piores resultados percentuais, e o premium os melhores.

The current management of colorectal cancer liver metastasis (CRCLM) patients involves a multidisciplinary approach, with surgical resection remaining the primary curative option. The advances in liver surgery have improved outcomes, enabling more patients to undergo surgery successfully. In addition, the development of imaging software has improved the preoperative planning and patient selection for surgery and other interventions. Systemic therapies, such as targeted therapies and immunotherapies, have enhanced the chances of complete resection. Targeted agents, in combination with chemotherapy, have shown efficacy in downstaging tumors and increasing resectability. The algorithm approach for these patients continues to evolve, driven by a deeper understanding of the underlying biology. Personalized medicine, guided by molecular profiling and the potential of liquid biopsies in this field, may lead to more tailored treatment strategies. A greater understanding of the immune microenvironment in CRLM may unlock the potential for immune checkpoint inhibitors and novel immunotherapies to become more prominent in the treatment landscape. This review explores the current state-of-the-art treatment of CRCLM and discusses promising future perspectives.

We analyzed the influence of exercise order using the bench press and squat as the first or second exercise of the session on velocity performance. Ten male trained individuals (20.9 ± 0.7 years) randomly performed two protocols of three sets of six repetitions at 80% of their one-repetition maximum with different exercise sequences: the bench press followed by the squat (BP + S) and the squat followed by the bench press (S + BP). A linear velocity transducer attached to the Smith machine barbell measured the mean propulsive velocity (MPV), peak velocity (PV), and time to peak velocity. Additionally, blood lactate and heart rate were measured. Regarding the bench press, differences were found in the MPV in the first (BP + S: 0.50 ± 0.07 m·s−1 vs. S + BP: 0.42 ± 0.08 m·s−1; p = 0.03, g = 0.72) and second sets (0.50 ± 0.06 m·s−1 vs. 0.42 ± 0.07 m·s−1; p = 0.03, g = 0.73), and in the PV in the second set (0.74 ± 0.09 m·s−1 vs. 0.63 ± 0.09 m·s−1; p = 0.02, g = 0.86). Regarding the squat, although the S + BP sequence tended to show higher velocities, no significant differences were found between protocols. These results showed that squatting first decreased subsequent bench press velocity performance. On the other hand, squat velocity performance was not impaired when preceded by the bench press.

RESUMO Este trabalho teve como objetivo avaliar o teor de nutrientes em solos sob sistemas agroflorestais manejados com e sem queima da vegetação, em uma propriedade de agricultura familiar na comunidade Benjamim Constant, no município de Bragança-PA. Para o desenvolvimento deste estudo, foram estabelecidas três áreas experimentárias: 1) sistema agroflorestal com corte e queima da vegetação; 2) sistema agroflorestal sem queima e com raleamento da vegetação, e 3) floresta secundária de 30 anos de idade. Em cada área, foram coletadas amostras de terra nas profundidades 0-5; 5-10; 10-20 cm. Na ocorrência de diferenças significativas entre os tratamentos, o teste de Tukey foi utilizado para comparar as médias, considerando-se um nível de 5% de probabilidade. Os maiores valores de pH, fósforo e acidez potencial foram observados no sistema manejado com queima da vegetação, provavelmente por causa de o experimento encontrar-se em anos iniciais e o efeito fertilizador das cinzas ainda se fazer no solo.

The study aimed to compare the effects of two warm-up strategies on mechanical force production during bench press and squat resistance training sessions. Twenty-six trained male subjects (24.37±5.83years, 75.48±12.12kg, 1.74±0.07m) performed a squat or bench press resistance training session after a specific warm-up (SWU) or general warm-up followed by a specific warm-up (GSWU). The SWU included 2x6 repetitions at 32% and 64% of the maximal load (1RM), respectively. The GSWU included 10 minutes of treadmill running (70% of heart rate reserve) followed by SWU. The resistance training session consisted of 3x6 with a load of 80% 1RM. Mechanical (mean propulsive velocity, mean propulsive power and velocity loss), physiological [heart rate (HR), blood lactate concentration], and psychophysiological variables (rating of perceived exertion) were evaluated. In the bench press and squat resistance training sessions, no differences were found in the mechanical and psychophysiological variables. When performing the bench press, the GSWU caused an increased HR response after warm-up (100.00±16.93bpm vs. 110.57±9.69bpm, p=0.03; ES=0.65, moderate effect). GSWU or SWU can both be used as preparatory activities for bench press and squat resistance training performance without related restrictions. These findings may be helpful for professionals to provide appropriate warm-up strategies to maximize resistance training. Keywords: Pre-exercise, Strength, T-Force, Velocity, Physiology, Resistance Training