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The fundamental building block of living organisms is the cell, which is the universal biological base of all living entities. This micrometric mass of cytoplasm and the membrane border have fascinated scientists due to the highly complex and multicompartmentalized structure. This specific organization enables numerous metabolic reactions to occur simultaneously and in segregated spaces, without disturbing each other, but with a promotion of inter- and intracellular communication of biomolecules. At present, artificial nano- and microcompartments, whether as single components or self-organized in multicompartment architectures, hold significant value in the study of life development and advanced functional materials and in the fabrication of molecular devices for medical applications. These artificial compartments also possess the properties to encapsulate, protect, and control the release of bio(macro)molecules through selective transport processes, and they are capable of embedding or being connected with other types of compartments. The self-assembly mechanism of specific synthetic compartments and thus the fabrication of a simulated organelle membrane are some of the major aspects to gain insight. Considerable efforts have now been devoted to design various nano- and microcompartments and understand their functionality for precise control over properties. Of particular interest is the use of polymeric vesicles for communication in synthetic cells and colloidal systems to reinitiate chemical and biological communication and thus close the gap toward biological functions. Multicompartment systems can now be effectively created with a high level of hierarchical control. In this way, these structures can not only be explored to deepen our understanding of the functional organization of living cells, but also pave the way for many more exciting developments in the biomedical field.
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Adaptive laboratory evolution (ALE) is a powerful tool for enhancing the fitness of cell lines in specific applications, including recombinant protein production. Through adaptation to nonstandard culture conditions, cells can develop specific traits that make them high producers. Despite being widely used for microorganisms and, to lesser extent, for mammalian cells, ALE has been poorly leveraged for insect cells. Here, we describe a method for adapting insect High Five and Sf9 cells to nonstandard culture conditions via an ALE approach. Aiming to demonstrate the potential of ALE to improve productivity of insect cells, two case studies are demonstrated. In the first, we adapted insect High Five cells from their standard pH (6.2) to neutral pH (7.0); this adaptation allowed to improve production of influenza virus-like particles (VLPs) by threefold, using the transient baculovirus expression vector system. In the second, we adapted insect Sf9 cells from their standard culture temperature (27 °C) to hypothermic growth (22 °C); this adaptation allowed to improve production of influenza VLPs by sixfold, using stable cell lines. These examples demonstrate the potential of ALE for enhancing productivity within distinct insect cell hosts and expression systems by manipulating different culture conditions.
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Proteínas Recombinantes , Animais , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Linhagem Celular , Células Sf9 , Baculoviridae/genética , Técnicas de Cultura de Células/métodos , Insetos/genética , Insetos/citologia , Evolução Molecular Direcionada/métodos , Concentração de Íons de Hidrogênio , TemperaturaRESUMO
Parasitic infections (PIs) remain a public health concern among school-age children living in areas of greater socioeconomic vulnerability, especially in Brazil, Russia, India, China, and South Africa. PIs can promote nutritional deficiencies, increasing the risk of anemia and impaired physical and cognitive development. Thus, fortified foods have been considered as a promising strategy for improving the nutritional status of children and preventing PI complications. This systematic review aimed to present the effects of iron-fortified foods for deworming and improving blood parameters in schoolchildren residing in areas that are vulnerable to PIs. This review is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines of randomized clinical trials addressing the use of fortified foods and micronutrients in children living in areas endemic for PIs. The PubMed, LILACS, Scopus, and Cochrane databases were searched to identify articles published between 2000 and 2020. A total of 153 records were retrieved from the databases, 10 of which were considered eligible for this study. On the basis of our analysis, most of the selected studies showed that the inclusion of fortified foods in the diet improved blood and infectious parameters. Therefore, fortified foods can be used as an important tool for controlling the adverse outcomes of PIs among children living in areas of greater vulnerability. However, more studies on this topic are needed to provide more evidence and consolidate strategies using iron-fortified food.
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Pyruvate:quinone oxidoreductases (PQOs) catalyse the oxidative decarboxylation of pyruvate to acetate and concomitant reduction of quinone to quinol with the release of CO2. They are thiamine pyrophosphate (TPP) and flavin-adenine dinucleotide (FAD) containing enzymes, which interact with the membrane in a monotopic way. PQOs are considered as part of alternatives to most recognized pyruvate catabolizing pathways, and little is known about their taxonomic distribution and structural/functional relationship. In this bioinformatics work we tackled these gaps in PQO knowledge. We used the KEGG database to identify PQO coding genes, performed a multiple sequence analysis which allowed us to study the amino acid conservation on these enzymes, and looked at their possible cellular function. We observed that PQOS are enzymes exclusively present in prokaryotes with most of the sequences identified in bacteria. Regarding the amino acid sequence conservation, we found that 75 amino acid residues (out of 570, on average) have a conservation over 90 %, and that the most conserved regions in the protein are observed around the TPP and FAD binding sites. We systematized the presence of conserved features involved in Mg2+, TPP and FAD binding, as well as residues directly linked to the catalytic mechanism. We also established the presence of a new motif named "HEH lock", possibly involved in the dimerization process. The results here obtained for the PQO protein family contribute to a better understanding of the biochemistry of these respiratory enzymes.
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Ácido Pirúvico , Quinona Redutases , Sequência de Aminoácidos , Flavina-Adenina Dinucleotídeo/metabolismo , Proteínas , Quinona Redutases/metabolismo , Aminoácidos , NAD(P)H Desidrogenase (Quinona)/metabolismo , QuinonasRESUMO
O termo "desinvestimento" se refere ao processo de retirada de recursos de intervenções que oferecem pouco ou nenhum ganho em saúde frente a seu custo. O intuito deste processo é reforçar práticas comprovadamente seguras, efetivas ou mais custo-efetivas, otimizando os resultados em saúde e a sustentabilidade econômica dos sistemas de saúde. O objetivo do trabalho foi caracterizar o processo de desinvestimento de medicamentos conduzido pela Comissão Nacional de Incorporação de Tecnologias (CONITEC) no Sistema Único de Saúde (SUS) entre 2012 e 2022, de forma exploratória através de análise documental dos seus relatórios técnicos de recomendações. Foram coletados nome do medicamento; sua classificação pelo sistema ATC; indicação clínica; demandante; realização de Consulta Pública; modalidade de desinvestimento recomendada e justificativa para o desinvestimento. Também foi avaliado o alinhamento das diretrizes de tratamento com as decisões de desinvestimento e o status de registro sanitário das tecnologias desinvestidas em diferentes ocasiões. Foram avaliados 30 relatórios de recomendação, correspondentes a 90 medicamentos. Três relatórios tiveram como recomendação a manutenção de sete tecnologias de perfil diversificado no SUS. Outros três relatórios eram referentes a tecnologias que foram incorporadas sob a modalidade ad experimentum e que, portanto, foram reavaliadas após três anos no SUS. Quanto às tecnologias efetivamente desinvestidas (80), elas se dividiram principalmente pelos grupos L (agentes antineoplásicos e imunomoduladores; 29,3%), J (anti-infecciosos de uso sistêmico; 21,3%) e A (aparelho digestivo e metabolismo; 20%). As principais indicações clínicas dos medicamentos desinvestidos foram: artrite reumatoide; HIV; hepatite C; e doença de Crohn. Justificativas mais mencionadas foram a indisponibilidade de registro ativo do medicamento no país (24,1%), seguida por problemas relacionados à segurança (20,6%) e efetividade (19,9%). Todas as demandas tiveram origem interna do Ministério da Saúde. Em 31,3%, houve exclusão do medicamento para indicação específica e, em 30%, exclusão total do sistema de saúde; em 27,5%, optou-se por excluir apenas determinada apresentação farmacêutica; em 10% as exclusões foram de apresentação para indicação específica; e em 1,2% ocorreu restrição de uso. Consulta Pública foi realizada em 36% dos casos. Após a publicação da Diretriz de Avaliação de Desempenho de Tecnologias em Saúde no final de 2016, o perfil de medicamentos desinvestidos por categoria ATC e por indicações clínicas adquiriram maior diversidade; as justificativas para o desinvestimento, que antes focavam em questões relacionadas a efetividade e segurança, passaram a se concentrar na indisponibilidade do medicamento no mercado; as modalidades de desinvestimento se acumularam mais em exclusões do SUS e exclusões de apresentação, e a Secretaria de Ciência, Tecnologia, Inovação e Insumos Estratégicos se tornou a principal demandante; submissão a consultas públicas subiu de 11,9% para 86,8%. O máximo de adequação estrutural identificado nos relatórios em relação aos tópicos preconizados pela Diretriz foi de 46,2%. Embora as iniciativas de desinvestimento tenham avançado nos últimos anos, o tema ainda enfrenta dificuldades para estabelecer uma agenda sólida no país.
Disinvestment refers to withdrawing resources from interventions that offer little or no health gain compared to their cost, seeking to reinforce practices proven to be safe, effective or more cost-effective and to optimize health outcomes and the economic sustainability of health systems. This study aimed to characterize the drug divestment process conducted by the National Commission for Incorporation of Technologies (CONITEC) in the Brazilian Unified Health System (SUS) between 2012 and 2022, in an exploratory way through their the technical recommendations reports. Drug name and ATC classification, clinical indication, proponents, occurrence of Public Consultation, recommended divestment modality and justifications for disinvestment were evaluated. We also evaluated the agreement of treatment guidelines with disinvestment decisions and the sanitary registration status of technologies disinvested at different times. We evaluated 30 recommendations reports corresponding to 90 drugs. Three reports recommended the maintenance of seven technologies in SUS. Another three reports referred to technologies that were incorporated under the ad experimentum modality and then were reassessed after three years in SUS. As for the technologies effectively disinvested (80), the drugs mainly belonged to the ATC classes L (29.3%), J (21.3%) and A (20%). The main clinical indications of the disinvested drugs were: rheumatoid arthritis, HIV, hepatitis C, and Crohn's disease. The main justifications were absence of market approval for the drug in Brazil (24.1%) and problems related to safety (20.6%) and effectiveness (19.9%). All requests were from the Brazilian Ministry of Health. Public Consultation was carried out in 36% of the situations. There were recommendations to exclude the drug for a specific indication in 31.3% of the cases and total exclusion from the SUS in 30%; exclusion of a particular pharmaceutical presentation and exclusion of presentation for a specific indication occurred in 27.5% and 10%, respectively. After the publication of the Methodological Guideline for Performance Avaliation of Health Technologies ate the end of 2016, the profile of drugs disinvested by ATC category and by clinical indications acquired bigger diversity; the justifications for disinvestment, which previously focused on issues related to effectiveness and safety, passed to focus on the unavailability of the drug on the market; disinvestment modalities concentrated more on SUS exclusions and presentation exclusions; the Secretaria of Science, Technology, Innovation and Strategic Insums became the main proponent of disinvestment demands; submission to public consultations grow up from 11.9% to 86.8%. The maximum structural adequacy identified of the reports in relation to the topics recommended by the Guideline was 46,2%. The lack of standardization and overly simplified reporting formats stood out. Although divestment initiatives have advanced in recent years, this theme still needs to improve in establishing a solid agenda in Brazil.
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Avaliação da Tecnologia Biomédica , Tomada de Decisões Gerenciais , Sistema Único de Saúde , Custos de Medicamentos , Gestão em Saúde , BrasilRESUMO
Adeno-associated viruses (AAVs) demand for clinical trials and approved therapeutic applications is increasing due to this vector's overall success and potential. The high doses associated with administration strategies challenges bioprocess engineers to develop more efficient technologies and innovative strategies capable of increasing volumetric productivity. In this study, alternating tangential flow (ATF) and Tangential Flow Depth filtration (TFDF) techniques were compared as to their potential for 1) implementing a high-cell-density perfusion process to produce AAV8 using mammalian HEK293 cells and transient transfection, and 2) integrating AAV harvest and clarification units into a single step. On the first topic, the results obtained demonstrate that AAV expression improves with a medium exchange strategy. This was evidenced firstly in the small-scale perfusion-mocking study and later verified in the 2 L bioreactor operated in perfusion mode. Fine-tuning the shear rate in ATF and TFDF proved instrumental in maintaining high cell viabilities and, most importantly, enhancing AAV-specific titers (7.6 × 104 VG/cell), i.e., up to 4-fold compared to non-optimized perfusion cultures and 2-fold compared with batch operation mode. Regarding the second objective, TFDF enabled the highest recovery yields during perfusion-based continuous harvest of extracellular virus and lysate clarification. This study demonstrates that ATF and TFDF techniques have the potential to support the production and continuous harvest of AAV, and enable an integrated clarification procedure, contributing to the simplification of operations and improving manufacturing efficiency.
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The malaria asexual blood-stage antigen PfRipr and its most immunogenic fragment PfRipr5 have recently risen as promising vaccine candidates against this infectious disease. Continued development of high-yielding, scalable production platforms is essential to advance the malaria vaccine research. Insect cells have supplied the production of numerous vaccine antigens in a fast and cost-effective manner; improving this platform further could prove key to its wider use. In this study, insect (Sf9 and High Five) and human (HEK293) cell hosts as well as process-optimizing strategies (new baculovirus construct designs and a culture temperature shift to hypothermic conditions) were employed to improve the production of the malaria asexual blood-stage vaccine candidate PfRipr5. Protein expression was maximized using High Five cells at CCI of 2 × 106 cell/mL and MOI of 0.1 pfu/cell (production yield = 0.49 mg/ml), with high-purity PfRipr5 binding to a conformational anti-PfRipr monoclonal antibody known to hold GIA activity and parasite PfRipr staining capacity. Further improvements in the PfRipr5 expression were achieved by designing novel expression vector sequences and performing a culture temperature shift to hypothermic culture conditions. Addition of one alanine (A) amino acid residue adjacent to the signal peptide cleavage site and a glycine-serine linker (GGSGG) between the PfRipr5 sequence and the purification tag (His6) induced a 2.2-fold increase in the expression of secreted PfRipr5 over using the expression vector with none of these additions. Performing a culture temperature shift from the standard 27-22°C at the time of infection improved the PfRipr5 expression by up to 1.7 fold. Notably, a synergistic effect was attained when combining both strategies, enabling to increase production yield post-purification by 5.2 fold, with similar protein quality (i.e., purity and binding to anti-PfRipr monoclonal antibody). This work highlights the potential of insect cells to produce the PfRipr5 malaria vaccine candidate and the importance of optimizing the expression vector and culture conditions to boost the expression of secreted proteins.
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Protein production processes based on stable insect cell lines require intensification to be competitive with the insect cell-baculovirus expression vector system (IC-BEVS). High cell density (HCD) cultures operate continuously, capable of maintaining specific production rates for extended periods of time which may lead to significant improvements in production yields. However, setting up such processes is challenging (e.g., selection of cell retention device and optimization of dilution rate), often demanding the manipulation of large volumes of culture medium with associated high cost. In this study, we developed a process for continuous production of Gag virus-like particles (VLP) pseudotyped with a model membrane protein (influenza hemagglutinin, HA) at HCD using stable insect cells adapted to low culture temperature. The impact of the cell retention device (ATF vs. TFF) and cell-specific perfusion rate (CSPR) on cell growth and protein expression kinetics was evaluated. Continuous production of Gag-HA VLPs was possible using both retention devices and CSPR of 0.04 nL/cell.d; TFF induces higher cell lysis when compared to ATF at later stages of the process (kD = 0.009 vs. 0.005 h-1, for TFF and ATF, respectively). Reducing CSPR to 0.01-0.02 nL/cell.d using ATF had a negligible impact on specific production rates (rHA = 72-68 titer/109 cell.h and rp24 = 12-11 pg/106 cell.h in all CSPR) and on particle morphology (round-shaped structures displaying HA spikes on their surface) and size distribution profile (peaks at approximately 100 nm). Notably, at these CSPRs, the amount of p24 or HA formed per volume of culture medium consumed per unit of process time increases by up to 3-fold when compared to batch and perfusion operation modes. Overall, this work demonstrates the potential of manipulating CSPRs to intensify the continuous production of Gag-HA VLPs at HCD using stable insect cells to make them an attractive alternative platform to IC-BEVS.
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Plasmodium falciparum cysteine-rich protective antigen (PfCyRPA) has been identified as a promising blood-stage candidate antigen to include in a broadly cross-reactive malaria vaccine. In the last couple of decades, substantial effort has been committed to the development of scalable cost-effective, robust, and high-yield PfCyRPA production processes. Despite insect cells being a suitable expression system due to their track record for protein production (including vaccine antigens), these are yet to be explored to produce this antigen. In this study, different insect cell lines, culture conditions (baculovirus infection strategy, supplementation schemes, culture temperature modulation), and purification strategies (affinity tags) were explored aiming to develop a scalable, high-yield, and high-quality PfCyRPA for inclusion in a virosome-based malaria vaccine candidate. Supplements with antioxidants improved PfCyRPA volumetric titers by 50% when added at the time of infection. In addition, from three different affinity tags (6x-His, 4x-His, and C-tag) evaluated, the 4x-His affinity tag was the one leading to the highest PfCyRPA purification recovery yields (61%) and production yield (26 mg/L vs. 21 mg/L and 13 mg/L for 6x-His and C-tag, respectively). Noteworthy, PfCyRPA expressed using High Five cells did not show differences in protein quality or stability when compared to its human HEK293 cell counterpart. When formulated in a lipid-based virosome nanoparticle, immunized rabbits developed functional anti-PfCyRPA antibodies that impeded the multiplication of P. falciparum in vitro. This work demonstrates the potential of using IC-BEVS as a qualified platform to produce functional recombinant PfCyRPA protein with the added benefit of being a non-human expression system with short bioprocessing times and high expression levels.
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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) homotrimeric spike (S) protein is responsible for mediating host cell entry by binding to the angiotensin-converting enzyme 2 (ACE2) receptor, thus being a key viral antigen to target in a coronavirus disease 19 (COVID-19) vaccine. Despite the availability of COVID-19 vaccines, low vaccine coverage as well as unvaccinated and immune compromised subjects are contributing to the emergence of SARS-CoV-2 variants of concern. Therefore, continued development of novel and/or updated vaccines is essential for protecting against such new variants. In this study, we developed a scalable bioprocess using the insect cells-baculovirus expression vector system (IC-BEVS) to produce high-quality S protein, stabilized in its pre-fusion conformation, for inclusion in a virosome-based COVID-19 vaccine candidate. By exploring different bioprocess engineering strategies (i.e., signal peptides, baculovirus transfer vectors, cell lines, infection strategies and formulation buffers), we were able to obtain ~4 mg/L of purified S protein, which, to the best of our knowledge, is the highest value achieved to date using insect cells. In addition, the insect cell-derived S protein exhibited glycan processing similar to mammalian cells and mid-term stability upon storage (up to 90 days at -80 and 4 °C or after 5 freeze-thaw cycles). Noteworthy, antigenicity of S protein, either as single antigen or displayed on the surface of virosomes, was confirmed by ELISA, with binding of ACE2 receptor, pan-SARS antibody CR3022 and neutralizing antibodies to the various epitope clusters on the S protein. Binding capacity was also maintained on virosomes-S stored at 4 °C for 1 month. This work demonstrates the potential of using IC-BEVS to produce the highly glycosylated and complex S protein, without compromising its integrity and antigenicity, to be included in a virosome-based COVID-19 vaccine candidate.
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| INTRODUÇÃO: No contexto de reabilitação em gerontologia surge como destaque a melhoria da capacidade de execução de tarefas motoras a fim de promover a autonomia, dessa maneira, é preciso investigar ferramentas para viabilizar esse objetivo clinico. OBJETIVO: Avaliar o efeito de um treino com realidade virtual não imersiva sobre a execução da tarefa motora real em idosos. MATERIAIS E MÉTODO: Trata-se de um relato de casos, com intervenção única, utilizando o Nintendo® Wii com sujeitos de idade superior a 60 anos submetidos à intervenção com treinamento de arremesso no jogo wii sports resort, e avaliados com analise cinemática angular de vídeo com o software Kinovea®, antes e depois da intervenção, protocolo composto por uma bateria de dez arremessos, antes e após a intervenção, além da avaliação subjetiva da melhora pós-treino. RESULTADOS: Participaram da pesquisa 4 sujeitos, sendo 3 do sexo feminino, com média de idade 70,7 anos ± 7,13 e escolaridade 8 anos ± 6,16. Para as variáveis angulares verificou-se que, após o treino com Wii, houve acentuação na flexão de ombro e decréscimo no cotovelo para na postura inicial do arremesso; já na posição final do arremesso, ocorreu decréscimo na extensão de cotovelo e aumento da flexão de punho. Também foi verificado aumento do salto e diminuição no tempo de execução da tarefa. CONSIDERAÇÕES FINAIS: Diante disso é possível concluir que o Nintendo® Wii se mostra um recurso potencial para melhoria de gestos no âmbito real para idosos.
INTRODUCTION: In the context of rehabilitation in gerontology, the improvement of the ability to perform motor tasks is highlighted to promote autonomy, so it is necessary to investigate tools to achieve this clinical objective. OBJECTIVE: To evaluate the effect of training with non-immersive virtual reality on the execution of the real motor task in the elderly. MATERIALS AND METHOD: This is a case report, with a single intervention using the Nintendo® Wii, with subjects over 60 years old who underwent intervention with throw training in the game Wii sports resort and evaluated with video angular kinematic analysis with the Kinovea® software before and after the intervention, a protocol consisting of a battery of ten shots before and after the intervention, in addition to the subjective assessment of posttraining improvement. RESULTS: Four subjects participated in the research, 3 females, with a mean age of 70.7 years ± 7.13 and schooling 8 years ± 6.16. For the angular variables, it was found that, after training with the Wii, in the initial throwing posture, there was an accentuation in the shoulder flexion and a decrease in the elbow for the same movement in the final position. There was a decrease in the elbow extension and an increase in the wrist flexion. It was also verified an increase in the jump and a decrease in the task execution time. FINAL CONSIDERATIONS: Given this, it is possible to conclude that the Nintendo® Wii is a potential resource for improving gestures in real life for the elderly
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Idoso , Biotecnologia , AprendizagemRESUMO
Stable insect cell lines are emerging as an alternative to the insect cell-baculovirus expression vector system (IC-BEVS) for protein expression, benefiting from being a virus-free, nonlytic system. Still, the titers achieved are considerably lower. In this study, stable insect (Sf-9 and High Five) cells producing Gag virus-like particles (VLPs) were first adapted to grow under hypothermic culture conditions (22°C instead of standard 27°C), and then pseudotyped with a model membrane protein (influenza hemagglutinin [HA]) for expression of Gag-HA VLPs. Adaptation to lower temperature led to an increase in protein titers of up to 12-fold for p24 (as proxy for Gag-VLP) and sixfold for HA, with adapted Sf-9 cells outperforming High Five cells. Resulting Gag-HA VLPs producer Sf-9 cells were cultured to high cell densities, that is, 100 × 106 cell/ml, using perfusion (ATF® 2) in 1 L stirred-tank bioreactors. Specific p24 and HA production rates were similar to those of batch culture, enabling to increase volumetric titers by 7-8-fold without compromising the assembly of Gag-HA VLPs. Importantly, the antigen (HA) quantity in VLPs generated using stable adapted cells in perfusion was ≈5-fold higher than that from IC-BEVS, with the added benefit of being a baculovirus-free system. This study demonstrates the potential of combining stable expression in insect cells adapted to hypothermic culture conditions with perfusion for improving Gag-HA VLPs production.
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Técnicas de Cultura de Células , Proteína do Núcleo p24 do HIV/biossíntese , Glicoproteínas de Hemaglutininação de Vírus da Influenza/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Animais , Proteína do Núcleo p24 do HIV/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Proteínas Recombinantes de Fusão/genética , Células Sf9 , SpodopteraRESUMO
Herbivorous primates present a selective consumption profile and morphological adaptations to use the fibrous fraction of their diets. Brown howler monkeys (Alouatta guariba) are generalist herbivores; however, when kept under human care, they usually receive diets rich in fruits and with insufficient amounts of fiber. Thus, the objective of this study was to evaluate the effects of two levels of neutral detergent fiber (NDF) in howlers on apparent total tract digestibility coefficients (ATTDC), fecal consistency, and intestinal fermentation products. A group of 26 adult howler monkeys, 13 males and 13 females, were fed two diets formulated to have 33% or 40% NDF for 11 days, according to a randomized block design (N = 26). The block factor was the enclosures with one, two, or three individuals (each enclosure corresponded to an experimental unit), totaling in eight replicates per treatment. There were no differences in dry matter and nutrients intake between treatments (p > 0.05). The diet with 33% NDF resulted in higher (p < 0.05) ATTDC of crude protein and crude energy. However, lower fecal concentrations of short-chain fatty acids (SCFA) and dry matter were observed in the treatment with 33% NDF in contrast to the 40% NDF group (p < 0.05). We recommend the inclusion of higher fiber levels (40% NDF) in the diet of howler monkeys since there is evidence of greater production of SCFA and improvement in fecal consistency.
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Alouatta , Fibras na Dieta/metabolismo , Digestão , Ração Animal/análise , Animais , Dieta/veterinária , Feminino , Fermentação , Lactação , Masculino , NutrientesRESUMO
The use of non-standard culture conditions has proven efficient to increase cell performance and recombinant protein production in different cell hosts. However, the establishment of high-producing cell populations through adaptive laboratory evolution (ALE) has been poorly explored, in particular for insect cells. In this study, insect High Five cells were successfully adapted to grow at a neutral culture pH (7.0) through ALE for an improved production of influenza hemagglutinin (HA)-displaying virus-like particles (VLPs). A stepwise approach was used for the adaptation process, in which the culture pH gradually increased from standard 6.2 to 7.0 (ΔPh = 0.2-0.3), and cells were maintained at each pH value for 2-3 weeks until a constant growth rate and a cell viability over 95% were observed. These adapted cells enabled an increase in cell-specific HA productivity up to three-fold and volumetric HA titer of up to four-fold as compared to non-adapted cells. Of note, the adaptation process is the element driving increased specific HA productivity as a pH shift alone was inefficient at improving productivities. The production of HA-VLPs in adapted cells was successfully demonstrated at the bioreactor scale. The produced HA-VLPs show the typical size and morphology of influenza VLPs, thus confirming the null impact of the adaptation process and neutral culture pH on the quality of HA-VLPs produced. This work strengthens the potential of ALE as a bioprocess engineering strategy to improve the production of influenza HA-VLPs in insect High Five cells.
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Adaptive laboratory evolution (ALE) has been extensively used to modulate the phenotype of industrial model organisms (e.g. Escherichia. coli and Saccharomyces cerevisae) towards a specific trait. Nevertheless, its application to animal cells, and in particular to insect cell lines, has been very limited. In this study, we describe employing an ALE method to improve the production of HIV-Gag virus-like particles (VLPs) in stable Sf-9 and High Five cell lines. Serial batch transfer was used for evolution experiments. During the ALE process, cells were cultured under controlled hypothermic conditions (22⯰C instead of standard 27⯰C) for a prolonged period of time (over 3 months), which allowed the selection of a population of cells with improved phenotype. Adapted cells expressed up to 26-fold (Sf-9 cells) and 10-fold (High Five cells) more Gag-VLPs than non-adapted cells cultured at standard conditions. The production of HIV Gag-VLPs in adapted, stable insect Sf-9 cell lines was successfully demonstrated at bioreactor scale. The Gag-VLPs produced at 22⯰C and 27⯰C were comparable, both in size and morphology, thus confirming the null impact of adaptation process and hypothermic culture conditions on VLP's quality. This work demonstrates the suitability of ALE as a powerful method for improving yields in stable insect cell lines producing VLPs.
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Produtos do Gene gag/metabolismo , Infecções por HIV/virologia , HIV/imunologia , Insetos/virologia , Vacinas de Partículas Semelhantes a Vírus/metabolismo , Animais , Linhagem Celular , Produtos do Gene gag/genética , Infecções por HIV/prevenção & controle , Vacinas de Partículas Semelhantes a Vírus/genéticaRESUMO
Glioblastoma (GBM) is one of the most common central nervous system cancers. It is characterized as a fast-growing tumor that arises from multiple cell types with neural stem-cell-like properties. Additionally, GBM tumors are highly invasive, which is attributed to the presence of glioblastoma stem cells that makes surgery ineffective in most cases. Currently, temozolomide is the unique chemotherapy option approved by the U.S. Food and Drug Administration for GBM treatment. This review analyzes the emergence and development of new synthetic small molecules discovered as promising anti-glioblastoma agents. A number of compounds were described herein and grouped according to the main chemical class used in the drug discovery process. Importantly, we focused only on synthetic compounds published in the last 10 years, thus excluding natural products. Furthermore, we included in this review only those most biologically active compounds with proven in vitro and/or in vivo efficacy.
Assuntos
Glioblastoma/tratamento farmacológico , Animais , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Descoberta de Drogas , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologiaRESUMO
Objetivo: investigar as taxas, as características, os fatores associados e as medidas preventivas relacionadas às quedas entre crianças e adolescentes em hospitais. Método: revisão integrativa de literatura realizada nas bases Scientific Electronic Library Online, Biblioteca Virtual em Saúde, National Library of Medicine e Google Scholar. Resultados: dez estudos atenderam aos critérios estabelecidos. As taxas variaram de 0.6 a 1.7 quedas por 1000 pacientes/dia. Grande parte das quedas ocorrem entre crianças do sexo masculino; com idade inferior a 9 anos. A maioria desses incidentes ocorrem na presença de um adulto. São fatores de risco para a ocorrência de quedas: idade da criança (p<0.01); tempo de internação (p<0.05); hiperatividade (p<0.01); distúrbios hematológicos (p<0.05); quedas anteriores (p<0.01); dimensionamento da enfermagem (p<0.00); escolaridade do cuidador (p<0.01) e o fato de o mesmo ser tabagista (p<0.01). As medidas preventivas adotadas foram: uso de berço e camas adequados para a idade, avaliação do risco de quedas, intervenções educacionais e uso de identificadores de alerta. Conclusão: A grande variação nas taxas de quedas entre os estudos sugere diferentes modos de organização do cuidado. A ocorrência de quedas no ambiente hospitalar entre crianças pode estar relacionada a fatores intrínsecos do paciente, do cuidador, ambientais e de organização do cuidado.
Objective: to investigate rates, characteristics, associated factors and preventive measures related to falls among children and adolescents in hospitals. Method: integrative literature review on the Scientific Electronic Library Online, Virtual Health Library, National Library of Medicine and Google Scholar. Results: ten studies met the established criteria. Rates ranged from 0.6 to 1.7 falls per 1000 patients / day. Most falls occur among male children; under the age of nine years old. Most of these incidents occur in the presence of an adult. Risk factors for falls are: age of the child (p <0.01); length of hospital stay (p <0.05); hyperactivity (p <0.01); hematological disorders (p <0.05); previous falls (p <0.01); nursing design (p <0.00); (p <0.01) and the fact that it was smoker (p <0.01). The preventive measures adopted were: use of cots and adequate beds for the age, evaluation of the risk of falls, educational interventions and use of alert identifiers. Conclusion: The large variation in falls rates between studies suggests different modes of care organization. The occurrence of falls in the hospital environment among children may be related to intrinsic patient, caregiver, environmental and care organization factors
Objetivo: investigar las tasas, las características, los factores asociados y las medidas preventivas relacionadas con las caídas entre niños y adolescentes en hospitales. Método: revisión integrativa de literatura realizada en las bases Scientific Electronic Library Online, Biblioteca Virtual en Salud, National Library of Medicine y Google Scholar. Resultados: diez estudios atendieron a los criterios establecidos. Las tasas variaron de 0.6 a 1.7 caídas por 1000 pacientes / día. Gran parte de las caídas ocurren entre los varones; con una edad inferior a 9 años. La mayoría de estos incidentes ocurren en presencia de un adulto. Son factores de riesgo para la ocurrencia de caídas: edad del niño (p <0.01); tiempo de internación (p <0.05); hiperactividad (p <0.01); trastornos hematológicos (p <0.05); caídas anteriores (p <0.01); el tamaño de la enfermería (p <0.00); escolaridad del cuidador (p <0.01) y el hecho de que el mismo sea tabacal (p <0.01). Las medidas preventivas adoptadas fueron: uso de cuna y camas adecuadas para la edad, evaluación del riesgo de caídas, intervenciones educativas y uso de identificadores de alerta. Conclusión: La gran variación en las tasas de caídas entre los estudios sugiere diferentes modos de organización del cuidado. La ocurrencia de caídas en el ambiente hospitalario entre niños puede estar relacionada a factores intrínsecos del paciente, del cuidador, ambientales y de organización del cuidado.
Assuntos
Humanos , Criança , Adolescente , Pediatria , Gestão de Riscos , Acidentes por Quedas , Criança Hospitalizada , Segurança do PacienteRESUMO
BACKGROUND: Cervical cancer, the fourth most common type of cancer among women worldwide, accounts for approximately 12% of all types of malignancies that affect women. Natural products have contributed significantly to the development of modern therapies; approximately 70% of the drugs available for chemotherapy are naturally based products. PURPOSE: The purpose of this study was to examine the biological activities of nitensidine B (NTB), a guanidinic alkaloid isolated from the leaves of Pterogyne nitens Tul. (Fabaceae) in a cervical cancer cell line. METHODS: In vitro experiments were performed using cervical carcinoma cells immortalized by human papillomavirus type 16 (HPV16, SiHa cells), since epidemiological and molecular studies have demonstrated robust associations between the etiologies of cervical cancer and HPV infection. Cytotoxicity as well as the effect of NTB treatment on intracellular signals of apoptosis, fragmentation of internucleosomal DNA via terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and levels of apoptosis effectors (Caspase 3/7) were evaluated. In addition, differential proteomic analysis (iTRAQ) and protein validation using western blot were performed. RESULTS: The cytotoxicity of NTB treatment in the SiHa cell line was concentration-dependent, with the minimum inhibitory concentration of 50% of the cells of 40.98⯵M. In the TUNEL assay, SiHa cell apoptosis with 3/7 caspase activation was reported at 12â¯h following treatment. Differential proteomic analysis by iTRAQ demonstrated that proteins of the glycolytic pathway, aldolase A, alpha-enolase, pyruvate kinase, and glyceraldehyde 3-phosphate dehydrogenase were underexpressed. CONCLUSION: These results indicated that NTB could play a role in decreasing glycolysis . Since tumor cells prefer the glycolytic pathway to generate energy, these findings suggest that NTB may be a reliable model for the study of human cervical cancer cell lines immortalized by HPV16, however more experiments can be performed.