Immobilization of a Commercial Lipase from Penicillium camembertii (Lipase G) by Different Strategies

The objective of this work was to select the most suitable procedure to immobilize lipase from Penicillium camembertii (Lipase G). Different techniques and supports were evaluated, including physical adsorption on hydrophobic supports octyl-agarose, poly(hydroxybutyrate) and Amberlite resin XAD-4; ionic adsorption on the anionic exchange resin MANAE-agarose and covalent attachment on glyoxyl-agarose, MANAE-agarose cross-linked with glutaraldehyde, MANAE-agarose-glutaraldehyde, and epoxy-silica-polyvinyl alcohol composite. Among the tested protocols, the highest hydrolytic activity (128.2 ± 8.10 IU·g−1 of support) was achieved when the lipase was immobilized on epoxy-SiO2-PVA using hexane as coupling medium. Lipase immobilized by ionic adsorption on MANAE-agarose also gave satisfactory result, attaining 55.6 ± 2.60 IU·g−1 of support. In this procedure, the maximum loading of immobilized enzyme was 9.3 mg·g−1 of gel, and the highest activity (68.8 ± 2.70 IU·g−1 of support) was obtained when 20 mg of protein·g−1 was offered. Immobilization carried out in aqueous medium by physical adsorption on hydrophobic supports and covalent attachment on MANAE-agarose-glutaraldehyde and glyoxyl-agarose was shown to be unfeasible for Lipase G. Thermal stability tests revealed that the immobilized derivative on epoxy-SiO2-PVA composite using hexane as coupling medium had a slight higher thermal stability than the free lipase

Chemical composition and anti-inflammatory evaluation of essential oils from leaves and stem barks from Drimys brasiliensis Miers (Winteraceae)

The essential oils from leaves and stem barks from Drimys brasiliensis Miers (Winteraceae) were individually obtained by hydrodistillation and their compounds characterized by use of GC/FID and GC/MS. The main identified derivatives were monoterpenes (leaves 4.31% and stem barks 90.02%) and sesquiterpenes (leaves 52.31% and stem barks 6.35%). Additionally, the sesquiterpene polygodial was isolated from hexane extract from stem barks of D. brasiliensis after chromatographic steps and characterized by spectroscopic means, mainly NMR. Aiming the evaluation of anti-inflammatory potential, the crude essential oils and the sesquiterpene polygodial were subjected to bioassays to evaluate the acute toxicity of these compounds as well as the anti-inflammatory and antinociceptive activities induced by carrageenan and formalin in mices. Ours results showed that essential oil obtained from the stem barks significantly reduced the oedema induced by carrageenan. The anti-inflammatory effect induced by stem barks oil (at 200 mg kg-1) was similar to observed for indomethacin (at 10 mg kg-1) and superior for polygodial (at 200 mg kg-1) in 30 and 60 min after the administration of essential oils. The inflammatory response induced by formalin was effective to the stem barks oil (62.5%) in comparison to polygodial (50.0%).Os óleos essenciais das folhas e das cascas do tronco de Drimys brasiliensis Miers (Winteraceae) foram obtidos individualmente por hidrodestilação e suas composições químicas foram determinadas através de análise por CG/DIC e CG/EM. Os principais constituintes identificados foram monoterpenos (folhas 4,31% e cascas do tronco 90,02%) e sesquiterpenos (folhas 52,31% e cascas do tronco 6,35%). Adicionalmente, o sesquiterpeno poligodial foi isolado do extrato em hexano das cascas do tronco de D. brasiliensis após fracionamento cromatográfico e caracterizado por métodos espectroscópicos. Visando a avaliação do potencial anti-inflamatório, os óleos essenciais brutos e o sesquiterpeno poligodial foram submetidos à bioensaios para avaliação da toxicidade aguda destes compostos bem como das atividades anti-inflamatória e antinociceptiva induzidas por carragenina e formalina em ratos. Nossos resultados mostraram que o óleo essencial bruto obtido das cascas do tronco reduziu significativamente o edema induzido por carragenina. O efeito anti-inflamatório induzido pelo óleo das cascas do tronco (a 200 mg kg-1) foi similar ao observado para indometacina (a 10 mg kg-1) e superior ao poligodial (a 200 mg kg-1) em 30 e em 60 min após administração. A resposta inflamatória induzida pela formalina foi efetiva para o óleo das cascas do tronco (62,5%) em comparação ao poligodial (50,0%).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo (UNIFESP) Departamento de Ciências Exatas e da TerraUniversidade Presbiteriana Mackenzie Departamento de Ciências Exatas e da Terra Centro de Ciências e Humanidades Centro de Ciências Biológicas e da SaúdeUniversidade Presbiteriana Mackenzie Centro de Ciências Biológicas e da SaúdeUNIFESP, Depto. de Ciências Exatas e da TerraSciEL

Modeling of FiO2 delivered by self-inflating ventilation device: Modelagem de FiO2 entregue por bolsa auto inflável

During the COVID-19 pandemic, professionals in the medical field have been using bag resuscitators, also called bag valve masks, to provide respiratory support for patients for long periods. A relevant issue arising because of such use is the little information regarding the FiO2 delivered by these devices, leading to toxic effects of O2 and its waste. This paper presents a model that relates volume, respiratory frequency, and flow in an O2 line with the FiO2 delivered by bag resuscitators. The model was obtained based on a formal procedure and data from a 1500 ml Hsiner bag resuscitator collected in the literature, both presented in this paper. Then, we compared through Bland-Altman analysis the FiO2 values estimated by our model with the ones from data considering different bag resuscitators to evaluate the amplitude of the errors it can generate. The average error for Hsiner and Laerdal bag resuscitators was less than 0.035 (or 3.5%) and less than 0.063 (or 6.3%) for Ambu devices. The maximum error found for Ambu bag resuscitators was high. The obtained model presented satisfactory errors, compatible with the uncertainty levels associated with FiO2 measuring instruments and blenders, meaning the model can be used to estimate the delivered FiO2 accurately. Additionally, the procedure presented in this paper can be used to obtain specific models for bag resuscitators of other companies, equipping professionals with tools that can accurately estimate FiO2

Aging-related predictive factors for oxygenation improvement and mortality in COVID-19 and acute respiratory distress syndrome (ARDS) patients exposed to prone position: A multicenter cohort study

Background: Elderly patients are more susceptible to Coronavirus Disease-2019 (COVID-19) and are more likely to develop it in severe forms, (e.g., Acute Respiratory Distress Syndrome [ARDS]). Prone positioning is a treatment strategy for severe ARDS; however, its response in the elderly population remains poorly understood. The main objective was to evaluate the predictive response and mortality of elderly patients exposed to prone positioning due to ARDS-COVID-19. Methods: This retrospective multicenter cohort study involved 223 patients aged ≥ 65 years, who received prone position sessions for severe ARDS due to COVID-19, using invasive mechanical ventilation. The PaO2/FiO2 ratio was used to assess the oxygenation response. The 20-point improvement in PaO2/FiO2 after the first prone session was considered for good response. Data were collected from electronic medical records, including demographic data, laboratory/image exams, complications, comorbidities, SAPS III and SOFA scores, use of anticoagulants and vasopressors, ventilator settings, and respiratory system mechanics. Mortality was defined as deaths that occurred until hospital discharge. Results: Most patients were male, with arterial hypertension and diabetes mellitus as the most prevalent comorbidities. The non-responders group had higher SAPS III and SOFA scores, and a higher incidence of complications. There was no difference in mortality rate. A lower SAPS III score was a predictor of oxygenation response, and the male sex was a risk predictor of mortality. Conclusion: The present study suggests the oxygenation response to prone positioning in elderly patients with severe COVID-19-ARDS correlates with the SAPS III score. Furthermore, the male sex is a risk predictor of mortality

AVALIAÇÃO DA EFICIÊNCIA ANTIBACTERIANA DE EXTRATO DE Lentinula edodes E DA SOLUÇÃO AQUOSA DO LÁTEX DE Euphorbia tirucalli FRENTE À BACTÉRIA Streptococcus agalactiae: ESTUDOS PRELIMINARES

Streptococcus agalactiae é agente causador de enfermidades em seres humanos e animais, sendo uma das principais causas de mastite bovina e perdas econômicas para os produtores leiteiros. Ademais, este patógeno tem apresentado resistência a antimicrobianos que são amplamente utilizados nos diferentes setores de produção animal. Diante disto, métodos alternativos de tratamento têm sido investigados visando o combate desta bactéria, dentre estes fitoterápicos e fungos. Dois agentes terapêuticos: Lentinula edodes e Euphorbia tirucalli têm demonstrado bons resultados como antimicrobianos e imunoestimulantes contra outros patógenos. Entretanto, não há estudos que comprovem a eficácia destes agentes frente S. agalatiae. Portanto o objetivo do presente estudo foi avaliar a ação antimicrobiana de extrato de Lentinula edodes e Solução aquosa de Euphorbia tirucalli obtidos destes agentes contra S. agalactiae. Foram utilizadas 25 bactérias pertencentes ao banco de cultura do Laboratório de Microbiologia da UFLA, isoladas de mastite bovina e uma amostra ATCC BAA – 611como controle positivo dos testes. O método de concentração inibitória mínima (CIM) foi realizado para avaliar a eficiência dos extratos contra S. agalactiae utilizando uma faixa de concentração de 1000 μg/mL a 15,65 μg/mL, de cada um dos extratos. Não foi observada inibição de crescimento em nenhuma das amostras avaliadas, portanto as concentrações estudadas dos agentes não foram eficazes contra S. agalactiae.  Palavras-chave: mastite bovina. Fungo shiitake, coroa de cristo, GBS, Concentração inibitória mínima

The Antioxidant Capacity of Rosemary and Green Tea Extracts to Replace the Carcinogenic Antioxidant (BHA) in Chicken Burgers

The present study aimed to evaluate the effect of natural extracts (rosemary and green tea extracts) in frozen storage of chicken burgers. Chicken burger treatments were prepared as follows: control (CON), 20 mg BHA/kg (BHA20), 10 mg green tea extract/kg (GT10), 38 mg green tea extract/kg (GT38), 18.6 mg rosemary extract/kg (RO18), and 480 mg rosemary extract/kg (RO480). Analysis of physicochemical parameters, color, TBAR index, and sensory acceptance were performed at 0, 30, 60, and 120 days of storage at −18°C in burgers packaged in LDPE plastic bags. The addition of natural antioxidants did not affect (p>0.05) the color and physicochemical parameters of the chicken burgers. After 120 days at −18°C, the RO480 sample showed a TBAR index similar (p>0.05) to BHA20 (0.423 and 0.369 mg, resp.). Sensory acceptance did not differ (p>0.05) among the treatments throughout the storage period (p>0.05)

Antigenic and molecular evidence of Brucella sp.-associated epididymo-orchitis in frugivorous (Artibeus lituratus) and nectarivorous (Glossophaga soricina) bats in Brazil

This study included 47 free-ranging bats from the State of Minas Gerais, Brazil. Six bats (12.8%) had genital inflammatory lesions, and two of them (one Artibeus lituratus and one Glossophaga soricina, a frugivorous and a nectarivorous, respectively) were diagnosed with Brucella sp. infection through PCR, and antigens in intralesional macrophages were detected using immunohistochemistry

Pouteria macrophylla fruit extract microemulsion for cutaneous depigmentation : evaluation using a 3D pigmented skin model

Here, we verify the depigmenting action of Pouteria macrophylla fruit extract (EXT), incorporate it into a safe topical microemulsion and assess its effectiveness in a 3D pigmented skin model. Melanocytes-B16F10- were used to assess the EXT effects on cell viability, melanin synthesis, and melanin synthesis-related gene transcription factor expression, which demonstrated a 32% and 50% reduction of intra and extracellular melanin content, respectively. The developed microemulsion was composed of Cremophor EL®/Span 80 4:1 (w/w), ethyl oleate, and pH 4.5 HEPES buffer and had an average droplet size of 40 nm (PdI 0.40 ± 0.07). Skin irritation test with reconstituted epidermis (Skin Ethic RHETM) showed that the formulation is non-irritating. Tyrosinase inhibition was maintained after skin permeation in vitro, in which microemulsion showed twice the inhibition of the conventional emulsion (20.7 ± 2.2% and 10.7 ± 2.4%, respectively). The depigmenting effect of the microemulsion was finally confirmed in a 3D culture model of pigmented skin, in which histological analysis showed a more pronounced effect than a commercial depigmenting formulation. In conclusion, the developed microemulsion is a promising safe formulation for the administration of cutite fruit extract, which showed remarkable depigmenting potential compared to a commercial formulation

Purification and Crystal Growth of the Bismuth (III) Iodide-influence of Trace Impurities on the Crystal Quality

This work describes the experimental procedure of purification and preparation of BiI3 crystals by Repeated Vertical Bridgman technique, aiming a future application of this semiconductor crystal as a room temperature radiation detector. The BiI3 powder used as raw material was purified three times and, at each purification, the crystal was evaluated by systematic measurements of the reduction of the impurities, crystalline structure, stoichiometry and surface morphology. The reduction of the trace metal impurities in the BiI3, at each purification, was analyzed by Instrumental Neutron Activation Analysis (INAA), in order to evaluate the efficiency of the purification technique established in this work. It was demonstrated that the Repeated Bridgman technique is effective to reduce the concentration of many impurities in BiI3, such as Ag, As, Br, Cr, K, Mo, Na and Sb. The crystalline structure of the BiI3 crystal purified twice and three times was similar to BiI3 pattern. However, for BiI3 powder and purified once, an intensity contribution of the BiOI was observed in the diffractograms. Improvement in the stoichiometric ratio was observed at each purification step, as well as the crystal surface morphology