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Microalgae attract interest worldwide due to their potential for several applications. Scenedesmus is one of the first in vitro cultured algae due to their rapid growth and handling easiness. Within this genus, cells exhibit a highly resistant wall and propagate both auto- and heterotrophically. The main goal of the present work is to find scalable ways to produce a highly concentrated biomass of Scenedesmus rubescens in heterotrophic conditions. Scenedesmus rubescens growth was improved at the lab-scale by 3.2-fold (from 4.1 to 13 g/L of dry weight) through medium optimization by response surface methodology. Afterwards, scale-up was evaluated in 7 L stirred-tank reactor under fed-batch operation. Then, the optimized medium resulted in an overall productivity of 8.63 g/L/day and a maximum biomass concentration of 69.5 g/L. S. rubescens protein content achieved approximately 31% of dry weight, similar to the protein content of Chlorella vulgaris in heterotrophy.
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Chlorella vulgaris , Microalgas , Scenedesmus , Processos Heterotróficos , Scenedesmus/metabolismo , Biomassa , Microalgas/metabolismoRESUMO
The European Shock Tube for High-Enthalpy Research is a new state-of-the-art facility, tailored for the reproduction of spacecraft planetary entries in support of future European exploration missions, developed by an international consortium led by Instituto de Plasmas e Fusão Nuclear and funded by the European Space Agency. Deployed state-of-the-art diagnostics include vacuum-ultraviolet to ultraviolet, visible, and mid-infrared optical spectroscopy setups, and a microwave interferometry setup. This work examines the specifications and requirements for high-speed flow measurements, and discusses the design choices for the main diagnostics. The spectroscopy setup covers a spectral window between 120 and 5000 nm, and the microwave interferometer can measure electron densities up to 1.5 × 1020 electrons/m3. The main design drivers and technological choices derived from the requirements are discussed in detail herein.
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Interferometria , Astronave , Análise Espectral , PlanetasRESUMO
A transition metal-free protocol for the preparation of fluorescent and non-fluoresent 3-methylthio-4-arylmaleimides in a single step through a new rearrangement from thiazolidine-2,4-diones is described. By employing the optimized reaction conditions, a broad scope of derivatives was prepared in ≤97% yield. The reaction tolerated several substituted aryl groups, including the challenging preparation of pyridyl-containing derivatives. A series of control experiments strongly suggested that the new rearrangement involves a key isocyanate intermediate and a further reaction with in situ-generated methylthiomethyl acetate. The photophysical properties of some of the synthesized derivatives as well as their use in live cell imaging were also investigated, revealing that some of the substituted maleimides are capable of selectively staining different regions of the cells.
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MaleimidasRESUMO
For yeast cells, tolerance to high levels of ethanol is vital both in their natural environment and in industrially relevant conditions. We recently genotyped experimentally evolved yeast strains adapted to high levels of ethanol and identified mutations linked to ethanol tolerance. In this study, by integrating genomic sequencing data with quantitative proteomics profiles from six evolved strains (data set identifier PXD006631) and construction of protein interaction networks, we elucidate exactly how the genotype and phenotype are related at the molecular level. Our multi-omics approach points to the rewiring of numerous metabolic pathways affected by genomic and proteomic level changes, from energy-producing and lipid pathways to differential regulation of transposons and proteins involved in cell cycle progression. One of the key differences is found in the energy-producing metabolism, where the ancestral yeast strain responds to ethanol by switching to respiration and employing the mitochondrial electron transport chain. In contrast, the ethanol-adapted strains appear to have returned back to energy production mainly via glycolysis and ethanol fermentation, as supported by genomic and proteomic level changes. This work is relevant for synthetic biology where systems need to function under stressful conditions, as well as for industry and in cancer biology, where it is important to understand how the genotype relates to the phenotype.
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Proteômica , Saccharomyces cerevisiae , Etanol , Fermentação , Genômica , Saccharomyces cerevisiae/genéticaRESUMO
Methylthiolation reactions are usually explored to access organosulfur compounds using methanethiol, an extremely flammable and toxic compound. Herein, methylthiomethyl esters were successfully applied as novel methylthiolation reagents in a low cost, transition-metal-free methodology. These reagents allowed the methylthiolation of a wide scope of chalcones, acyl ester derivatives and Morita-Baylis-Hillman acetates with good group tolerance, affording the methylthiolated products in moderate to excellent yields. The reaction mechanism was investigated through several control experiments, as well as by theoretical calculations employing Density Functional Theory. The results strongly support that a sulfurane and a sulfonium ylide appear as key intermediates and that a Pummerer type rearrangement is also crucial for the formation of this novel reagent. Furthermore, the methylthiolation mechanism is likely to proceed through the nucleophilic attack of the reagent, followed by an entropically favoured step involving the acetate attack to the positively charged species, then releasing the product.
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Sorafenib has been widely used to treat unresectable hepatocellular carcinoma (HCC) but most studies have been done in Child-Pugh A (CP-A) patients with well-preserved liver function. We evaluated the overall survival (OS) and tolerance to sorafenib in a large cohort of Child-Pugh B (CP-B) HCC patients as compared to CP-A HCC patients. We prospectively studied 130 patients with advanced HCC who started sorafenib between January 2011 and December 2015. Patients were classified as CP-A (n = 65) or CP-B (n = 65). The average OS for all 130 patients was 10 months. CP-A patients had a median survival rate significantly longer than CP-B patients: 12 months vs. 6 months. The OS found in our group of CP-B patients was 6.5 months, which is higher than that found in most studies done so far. When stratified, our CP-B patients had better OS than ever reported. The dose of the drug was interrupted due to adverse events (AEs) in 38 (29%) of the patients, of whom 20 (30%) were CP-A patients and 18 (28%) were CP-B patients. This real-life cohort of CP-B HCC patients treated with sorafenib had a higher survival than that described in the literature, with a satisfactory safety profile. Despite the high prevalence of severe AEs in CP-B patients, there were fewer treatment interruptions in this group, indicating that Child-Pugh B patients can tolerate treatment and may benefit from sorafenib.
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Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Sorafenibe/uso terapêutico , Idoso , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/classificação , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/classificação , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , alfa-Fetoproteínas/análiseRESUMO
BACKGROUND: Portal vein obstructive lesions associated with hypertrophy of the hepatic artery territory are observed in Schistosoma mansoni schistosomiasis. Liver perfusion scintigraphy is a method used for evaluation of hepatic perfusion changes in liver diseases. It has been suggested that, like in cirrhosis, where compensatory increase in perfusion through the hepatic artery is documented, perfusion changes occur in hepatosplenic schistosomiasis (HSS). AIMS: This study aims to determine changes in liver hemodynamics using hepatic perfusion scintigraphy and correlate them with clinical and laboratory variables and ultrasound findings in HSS. METHODS: Nineteen patients with schistosomiasis underwent ultrasound evaluation of degree of liver fibrosis, splenic length, and splenic and portal vein diameter, digestive endoscopy, and quantification of platelets. Subsequently, perfusion scintigraphy with measurement of hepatic perfusion index (HPI) was performed. RESULTS: It was observed that patients with hepatosplenic schistosomiasis had significantly higher HPI compared with normal individuals (p = 0.0029) and that this increase correlated with splenic length (p = 0.038) and diameter of esophageal varices (p = 0.0060). Angioscintigraphy showed high accuracy for predicting presence of large esophageal varices. CONCLUSIONS: Angioscintigraphy could show that patients with HSS had increased HPI, featuring greater liver "arterialization," as previously described for cirrhotic patients. Correlations were also observed between HPI and longitudinal splenic length, caliber of esophageal varices, caliber of portal vein, and blood platelet count. Angioscintigraphy is a promising technique for evaluation of hepatosplenic schistosomiasis.
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Velocidade do Fluxo Sanguíneo/fisiologia , Hipertensão Portal/complicações , Hepatopatias Parasitárias/complicações , Fígado/irrigação sanguínea , Esquistossomose mansoni/patologia , Esplenopatias/complicações , Adulto , Idoso , Estudos Transversais , Técnicas de Diagnóstico por Radioisótopos , Feminino , Humanos , Hipertensão Portal/diagnóstico por imagem , Hipertensão Portal/fisiopatologia , Hepatopatias Parasitárias/diagnóstico por imagem , Hepatopatias Parasitárias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Esquistossomose mansoni/complicações , Esplenopatias/diagnóstico por imagem , Esplenopatias/fisiopatologia , UltrassonografiaRESUMO
Objective: To evaluate COVID-19 vaccination status in admitted children in 2020−2021 and during the OMICRON variant circulation (2022), a period when children older than 12 years of age had received two doses of COVID-19 vaccines. Design: An observational retrospective study. Patients with confirmed COVID-19 were compared in two different periods: 2020−2021 when adolescents aged 12−18 years had not received the complete COVID-19 vaccine, and 2022 when children older than 12 years had received the complete Pfizer-BioNTech vaccine scheme. Setting: Two pediatric hospitals in Rio de Janeiro city. Patients: Children aged < 18 years with confirmed COVID-19. Intervention: None. Main outcome: Vaccination status for COVID-19 on admission. Results: In total, 300 patients were admitted with confirmed COVID-19 (240 in 2020−2021 and 60 in 2022). The distribution of patients according to the age-groups was: 0−2 years (33.3% in 2020−2021 and 53.4% in 2022), 2−5 years (21.7% in 2020−2021 and 10% in 2022), 5−11 years (29.2% in 2020−2021 and 28.3% in 2022), and 12−18 years (15.8% in 2020−2021 and 8.3% in 2022) (p = 0.076). The median length of stay was six days in 2020−2021 and six days in 2022 (p = 0.423). We verified six deaths in the first analysis period and one death in the second one (p = 0.894). Of the 60 children admitted in 2022, 58 (96.7%) did not receive the complete COVID-19 vaccine scheme available. Conclusions: We verified in a "real-world condition" the ability of the Pfizer-BioNTech vaccine to prevent hospitalization in children over 12 years of age.
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The efficacy of direct-acting antivirals (DAAs) in the treatment of chronic hepatitis C (CHC) in liver transplant recipients is poorly understood, and several factors, including immunosuppression, drug interactions, elevated viraemia, and intolerance to ribavirin (RBV), can reduce cure rates. We conducted a real-life study on liver transplant recipients with CHC treated with a combination of sofosbuvir (SOF) and daclatasvir (DCV) or simeprevir (SIM), with or without RBV, followed-up for 12 to 24 weeks. The treatment effectiveness was assessed by determining the sustained virological response (SVR) rates at 12 or 24 weeks after the treatment cessation. Eighty-four patients were evaluated, with a mean age of 63.4 ± 7.4 years, HCV genotype 1 being the most prevalent (63.1%). Nineteen patients (22.7%) had mild fibrosis (METAVIR < F2) and 41 (48.8%) significant fibrosis (METAVIR ≥ F2). The average time between liver transplantation and the start of treatment was 4 years (2.1-6.6 years). The SOF + DCV regimen was used in 58 patients (69%). RBV in combination with DAAs was used in seven patients (8.3%). SVR was achieved in 82 patients (97.6%), and few relevant adverse events could be attributed to DAA therapy, including a patient who stopped treatment due to a headache. There was a significant reduction in ALT, AST, GGT and FA levels, or the APRI index after 4 weeks of treatment, which remained until 12/24 weeks post-treatment. DAA treatment of CHC in liver-transplanted patients achieved a high SVR rate and resulted in the normalization of serum levels of liver enzymes.
Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Transplante de Fígado/efeitos adversos , Ribavirina/uso terapêutico , Idoso , Antivirais/efeitos adversos , Brasil , DNA Viral/genética , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Humanos , Cirrose Hepática/cirurgia , Masculino , Pessoa de Meia-Idade , Ribavirina/efeitos adversos , Transplantados , Resultado do TratamentoRESUMO
OBJECTIVE: This study aimed to analyze the antimicrobial effects of lyophilized hydroalcoholic extract (HEScSeed and HEScFlower) and silver nanoparticles (AgNPs-HEScSeed and AgNPs-HEScFlower) of S. cumini seed and flower, and to characterize some compounds of these extracts and their NPs. DESIGN: Phytochemical screening was performed by GC-MS. Nanoparticles were characterized by UV-vis spectroscopy, energy-dispersive X-ray (EDX) spectrophotometry, scanning electron microscopy (SEM) and field emission gun (FEG), dynamic light scattering (DLS) and zeta potential (ZP). Antimicrobial susceptibility tests were analyzed by broth microdilution and agar diffusion methods. RESULTS: HEScSeed and HEScFlower showed 7 and 17 phytochemical compounds, respectively. AgNPs-plant extracts were reported as stable and with variable shapes and sizes. All studied species (A. naeslundii, C. albicans, F. nucleatum, S. aureus, S. epidermidis, S. mutans, S. oralis and V. dispar) were susceptible to extracts and AgNPs-plant extracts, with varying degrees of antimicrobial activities (extract: 648.4-5,187.5⯵g/mL; AgNPs-plant: 31.2-2,000⯵g/mL). CONCLUSION: The extracts of S. cumini seed and flower have antimicrobial action against pathogens of medical and dental interest, whose MIC and MMC are species-dependent. The AgNPs-HEScSeed and AgNPs-HEScFlower have different shapes, sizes, organic compounds, stability and electronegativity (capping), characteristics that contribute to their bacteriostatic and fungistatic effects, but at significantly lower concentrations than plant extracts.
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Anti-Infecciosos , Nanopartículas Metálicas , Syzygium , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Flores , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Sementes , Prata/farmacologia , Staphylococcus aureusRESUMO
Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Inflammatory monocytes are recruited to both the infection site and vital organs during sepsis; however, the mechanisms that orchestrate their migration, as well as the participation of these cells in systemic inflammation and vital organ damage, are still not fully elucidated. In this context, we described that CCR2-deficient mice had diminished migration of inflammatory monocytes from bone marrow to the circulation and subsequently to the site of infection and vital organs during cecal ligation and puncture (CLP)-induced polymicrobial sepsis. The reduction in the migration of inflammatory monocytes to the infection site was accompanied by a significant increase in the number of neutrophils in the same compartment, which seemed to counterbalance the absence of inflammatory monocytes in controlling microbial growth. Indeed, wild-type (WT) and CCR2-deficient mice under CLP presented similar control of infection. However, the CCR2-deficient mice were more resistant to sepsis, which was associated with a decrease in inflammatory mediators and organ damage biomarkers. Furthermore, the systemic adoptive transfer of CCR2-WT or CCR2-deficient inflammatory monocytes into CCR2-deficient mice equally increased the susceptibility to sepsis, demonstrating the deleterious role of these cells in the periphery even when CCR2 is absent. Thus, despite the host-protective role of inflammatory monocytes in controlling infection, our results demonstrated that the mechanism by which CCR2 deficiency shows protection to CLP-induced sepsis is due to a decrease of inflammatory monocytes emigration from bone marrow to the circulation and vital organs, resulting in the reduction of organ damage and systemic cytokine production.
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Medula Óssea/imunologia , Quimiotaxia de Leucócito/genética , Quimiotaxia de Leucócito/imunologia , Monócitos/imunologia , Monócitos/metabolismo , Receptores CCR2/deficiência , Sepse/etiologia , Sepse/metabolismo , Animais , Biomarcadores , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Predisposição Genética para Doença , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos KnockoutRESUMO
Microalgae are widely used as food supplements due to their high protein content, essential fatty acids and amino acids as well as carotenoids. The addition of microalgal biomass to food products (e.g., baked confectioneries) is a common strategy to attract novel consumers. However, organoleptic factors such as color, taste and smell can be decisive for the acceptability of foods supplemented with microalgae. The aim of this work was to develop chlorophyll-deficient mutants of Chlorella vulgaris by chemically induced random mutagenesis to obtain biomass with different pigmentations for nutritional applications. Using this strategy, two C. vulgaris mutants with yellow (MT01) and white (MT02) color were successfully isolated, scaled up and characterized. The changes in color of MT01 and MT02 mutant strains were due to an 80 and 99% decrease in their chlorophyll contents, respectively, as compared to the original wild type (WT) strain. Under heterotrophic growth, MT01 showed a growth performance similar to that of the WT, reaching a concentration of 5.84 and 6.06 g L-1, respectively, whereas MT02 displayed slightly lower growth (4.59 g L-1). When grown under a light intensity of 100 µmol m-2 s-1, the pigment content in MT01 increased without compromising growth, while MT02 was not able to grow under this light intensity, a strong indication that it became light-sensitive. The yellow color of MT01 in the dark was mainly due to the presence of the xanthophyll lutein. On the other hand, phytoene was the only carotenoid detected in MT02, which is known to be colorless. Concomitantly, MT02 contained the highest protein content, reaching 48.7% of DW, a 60% increase as compared to the WT. MT01 exhibited a 30% increase when compared to that of the WT, reaching a protein content of 39.5% of DW. Taken together, the results strongly suggest that the partial abrogation of pigment biosynthesis is a factor that might promote higher protein contents in this species. Moreover, because of their higher protein and lower chlorophyll contents, the MT01 and MT02 strains are likely candidates to be feedstocks for the development of novel, innovative food supplements and foods.
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Objetivo: demostrar la utilidad de la tomografía de coherencia óptica antes de la cirugía de catarata, para el diagnóstico de alteraciones de la mácula o de la capa de fibras neurorretinianas. Métodos: se realizó un estudio descriptivo de corte transversal de serie de casos en el Instituto Cubano de Oftalmología, de enero del año 2014 a diciembre de 2015, en 100 pacientes seleccionados al azar con catarata senil. Se realizaron exámenes del protocolo de la línea preoperatoria de catarata y tomografía de coherencia óptica. Las variables estudiadas fueron edad, sexo, tipo de catarata, bilateralidad, presencia de lesiones de la mácula o de la capa de fibras neurorretinianas, localización anatómica y tipo de lesiones de la mácula, lesiones de la capa de fibras neurorretinianas, antecedentes de enfermedades vasculares sistémicas, maculares y/o glaucoma y necesidad de tratamiento oftalmológico. Se consideró la media, el porcentaje, el intervalo de confianza y la prueba de probabilidades exactas de Fisher. Resultados: la edad promedio fue 70,13 años y predominó el sexo femenino (54,0 por ciento). Las lesiones tanto de mácula como de capa de fibras neurorretinianas se presentaron en el 39,0 por ciento de los pacientes. El 11,2 por ciento de los ojos con catarata tenían lesión en la interfase vitreomacular, con predominio de la membrana epirretinal (14,6 por ciento). En el 14,2 por ciento se detectó daño en capa de fibras neurorretinianas. No existió relación entre presencia de lesiones maculares y enfermedad macular (p= 0,275). En el 34,8 por ciento de los pacientes sin antecedentes de glaucoma había lesión de capa de fibras. El 28,8 por ciento de los pacientes con lesiones, necesitaba tratamiento previa cirugía. Conclusiones: la tomografía de coherencia óptica es una herramienta importante en el preoperatorio de la cirugía de catarata(AU)
Objective: demonstrate the usefulness of optical coherence tomography prior to cataract surgery to diagnose alterations of the macula and/or the neuroretinal fiber layer. Methods: a descriptive cross-sectional study of a case series was conducted at the Cuban Institute of Ophthalmology from January 2014 to December 2015. The study sample was a random selection of 100 patients with senile cataract who underwent protocol cataract surgery preoperative examination and optical coherence tomography. The variables studied were age, sex, cataract type, bilaterality, presence of macular and/or neuroretinal fiber layer lesions, anatomical location and macular lesion type, neuroretinal fiber layer lesions, history of systemic vascular or macular diseases and/or glaucoma, and need of ophthalmological treatment. Mean, percentage, confidence interval and Fisher's exact test were all considered. Results: mean age was 70.13 years. Female sex prevailed (54.0 percent). Macular and neuroretinal fiber layer lesions were present in 39.0 percent of the patients. 11.2 percent of the eyes with cataracts had a lesion in the vitreo-macular interface, with a predominance of the epiretinal membrane (14.6 percent). Damage to the neuroretinal fiber layer was detected in 14.2 percent. No relationship was found between the presence of macular lesions and macular disease (p= 0.275). 34.8 percent of the patients without a history of glaucoma had a fiber layer lesion. 28.8 percent of the patients with lesions needed pre-operative treatment. Conclusions: Optical coherence tomography is an important tool in the preoperative period of cataract surgery(AU)
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Humanos , Feminino , Idoso , Glaucoma/tratamento farmacológico , Tomografia de Coerência Óptica/métodos , Epidemiologia DescritivaRESUMO
Os autores caracterizaram a síndrome do anticorpo antifosfolipídeo, doença auto-imune que altera a hemocoagulaçäo e acarreta também vários problemas obstétricos. Atualizam a fisiopatologia desta síndrome, descrevendo os novos conhecimentos sobre os cofatores plasmáticos necessários à ligaçäo dos anticorpos aos fosfolipídeos. Apresentam o acompanhamento e tratamento das gestantes com síndrome do anticorpo antifosfolipíideo a fim de melhorar suas perspectivas de sucesso na gestaçäo
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Humanos , Feminino , Gravidez , Síndrome Antifosfolipídica/diagnóstico , Síndrome Antifosfolipídica/imunologia , Ensaio de Imunoadsorção Enzimática , Complicações na Gravidez , Gravidez de Alto Risco , Doenças Autoimunes/diagnósticoRESUMO
Os autores revisam o tema infecçäo pelo vírus HTLV-I (Human T Cell Lymphotropic Virus), sua transmissäo e conseqüências clínicas. FOcalizam preferencialmente a triagem de gestantes infectadas, o risco e forma de contaminaçäo de seus fetos e fazem orientaçäo com relaçäo à prevençäo
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Humanos , Feminino , Gravidez , Deltaretrovirus , Infecções por HTLV-I/prevenção & controle , Infecções por HTLV-I/transmissão , Complicações Hematológicas na Gravidez , Gravidez de Alto Risco , Paralisia Facial/etiologia , Polimiosite/etiologia , Polirradiculoneuropatia/etiologiaRESUMO
Os autores buscam revisar o tema, hiperplasia adrenal congênita, enfatizando a importância da precocidade do diagnóstico e do tratamento, já na vida intra-uterina. Apresentam métodos diagnósticos e tratamento, de maneira a evitar consequências importantes para os pacientes com esta doença