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1.
Int J Biol Macromol ; 261(Pt 1): 129701, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280709

RESUMO

The development of flexible and porous materials to control antibacterial delivery is a pivotal endeavor in medical science. In this study, we aimed to produce long and defect-free fibers made of zein and hydroxypropyl methylcellulose acetate succinate (HPMCAS) to be used as a platform for the release of metronidazole (MDZ) and metronidazole benzoate (BMDZ) to be potentially used in periodontal treatment. Microfibers prepared via electrospinning under a 2:3 (w/w) zein to HPMCAS ratio, containing 0.5 % (w/w) poly(ethylene oxide) (PEO) and 1 % (w/w) cellulose nanofibril (CNF) were loaded with 40 % (w/w) MDZ, 40 % (w/w) BMDZ, or a combination of 20 % (w/w) of each drug. The addition of CNF improved the electrospinning process, resulting in long fibers with reduced MDZ and BMDZ surface crystallization. MDZ- and BMDZ-incorporated fibers were semicrystalline and displayed commendable compatibility among drugs, nanocellulose and polymeric chains. Release tests showed that zein/HPMCAS/PEO fibers without CNF and with 20 % (w/w) MDZ/ 20 % (w/w) BMDZ released the drug at a slower and more sustained rate compared to other samples over extended periods (up to 5 days), which is a favorable aspect concerning periodontitis treatment.


Assuntos
Metilcelulose/análogos & derivados , Metronidazol , Zeína , Metronidazol/farmacologia , Celulose , Benzoatos
3.
Arq Bras Cardiol ; 120(7): e20220461, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-37556652

RESUMO

BACKGROUND: The transthoracic echocardiogram (TTE) plays a screening role in the diagnostic algorithm of pulmonary hypertension (PH). Studies have shown a significant disagreement between TTE measurements of the systolic pulmonary artery pressure (sPAP) and right atrial pressure (RAP) and those obtained by right heart catheterization (RHC). OBJECTIVE: To compare TTE measurements of sPAP and RAP with those obtained by RHC in patients being investigated for PH. METHODS: Patients referred to a PH reference center with a high or intermediate TTE probability of PH upon admission were submitted to RHC. The agreement between sPAP and RAP from both procedures was assessed through the Bland-Altman test. Differences of up to 10 mmHg for sPAP and 5 mmHg for RAP were considered within the variability of the test. Receiver Operating Characteristic (ROC) curve was constructed to determine the most accurate sPAP and Tricuspid regurgitation maximal velocity (TRV)values associated with the diagnosis of PH by RHC. The adopted level of statistical significance was 5%. RESULTS: Ninety-five patients were included. The Bland-Altman analysis showed a bias of 8.03 mmHg (95% CI:-34.9-50.9) for sPAP and -3.30 mmHg (95% CI:-15.9-9.3) for RAP. AUC for sPAP and TRV measured by TTE for discrimination of probable PH were 0.936 (95% CI: 0.836-1.0) and 0.919 (95% CI: 0.837-1.0), respectively. However, only 33.4% of the echocardiographic estimate of sPAP and 55.1% of RAP were accurate, as compared to the measurements obtained by RHC. CONCLUSION: TTE has a high discriminatory power as a screening diagnostic method for PH despite presenting disagreements between sPAP and RAP absolute values when compared to RHC measurements.


FUNDAMENTO: O ecocardiograma transtorácico (ETT) tem um papel de triagem no algoritmo diagnóstico da hipertensão pulmonar (HP). Estudos demonstraram uma discordância significativa entre as medições do ETT da pressão arterial pulmonar sistólica (PAPs) e da pressão atrial direita (PAD) e as obtidas pelo cateterismo do coração direito (CCD). OBJETIVO: Comparar as medições do ETT da PAPs e da PAD com as obtidas pelo CCD em pacientes com suspeita de HP. MÉTODOS: Pacientes encaminhados a um centro de referência com probabilidade alta ou intermediária de PH ao ETT na admissão hospitalar passaram por CCD. A concordância entre a PAPs e a PAD em ambos os procedimentos foi avaliada pelo teste de Bland-Altman. Diferenças de até 10 mmHg na PAPs e de até 5 mmHg na PAD foram consideradas dentro da variabilidade do teste. A curva de característica de operação do receptor (ROC) foi construída para determinar os valores mais precisos de PAPs e VRT associados ao diagnóstico de HP pelo CCD. O nível de significância estatística adotado foi 5%. RESULTADOS: Foram incluídos noventa e cinco pacientes. A análise de Bland-Altman análise revelou um viés de 8,03 mmHg (IC 95%: -34,9 a 50,9) na PAPs e -3,30 mmHg (IC 95%: -15,9 a 9,3) na PAD. AUC da PAPs e VRT medidas pelo ETT para a discriminação de provável HP foram de 0,936 (IC 95%: 0,836 a 1,0) e 0,919 (IC 95%: 0,837 a 1,0), respectivamente. Entretanto, apenas 33,4% da estimativa ecocardiográfica da PAPs e 55,1% da PAD foram precisas, em comparação às medições obtidas pelo CCD. CONCLUSÃO: O ETT tem um alto poder discriminatório como método diagnóstico de triagem para HP, apesar de apresentar discordâncias entre os valores absolutos de PAPs e PAD, em comparação às medições por CCD.


Assuntos
Hipertensão Pulmonar , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Ecocardiografia Doppler/métodos , Artéria Pulmonar/diagnóstico por imagem , Ecocardiografia , Cateterismo Cardíaco/métodos
4.
Primates ; 64(4): 415-419, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37233857

RESUMO

The Critically Endangered southern muriqui (Brachyteles arachnoides) and its sister taxon the northern muriqui (Brachyteles hypoxanthus) are endemic to the Atlantic Forest in Brazil. To date, our understanding of the distribution of the southern muriqui has restricted it to the states of Paraná, São Paulo, and Rio de Janeiro. The northern muriqui occurs in the states of Minas Gerais, Rio de Janeiro, Espírito Santo, and Bahia. Here, we describe the first record of the southern muriqui in Minas Gerais. A group of seven individuals, including one infant, was detected and photographed on  a private property in the district of Monte Verde, municipality of Camanducaia, on the northwestern slope of the Serra da Mantiqueira. This location is 5.3 km from a population of southern muriquis (known since 1994) on the southeastern slope of the serra in São Paulo. This discovery highlights the importance of further surveys in the Serra da Mantiqueira in order to detect any new populations, provide data for a more accurate assessment of the conservation status of the two species-the delimitation of their distributions, the size and extent of isolation of their populations, and the threats they face.


Assuntos
Atelinae , Animais , Brasil , Florestas
5.
Arq. bras. cardiol ; 120(7): e20220461, 2023. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1447306

RESUMO

Resumo Fundamento O ecocardiograma transtorácico (ETT) tem um papel de triagem no algoritmo diagnóstico da hipertensão pulmonar (HP). Estudos demonstraram uma discordância significativa entre as medições do ETT da pressão arterial pulmonar sistólica (PAPs) e da pressão atrial direita (PAD) e as obtidas pelo cateterismo do coração direito (CCD). Objetivo Comparar as medições do ETT da PAPs e da PAD com as obtidas pelo CCD em pacientes com suspeita de HP. Métodos Pacientes encaminhados a um centro de referência com probabilidade alta ou intermediária de PH ao ETT na admissão hospitalar passaram por CCD. A concordância entre a PAPs e a PAD em ambos os procedimentos foi avaliada pelo teste de Bland-Altman. Diferenças de até 10 mmHg na PAPs e de até 5 mmHg na PAD foram consideradas dentro da variabilidade do teste. A curva de característica de operação do receptor (ROC) foi construída para determinar os valores mais precisos de PAPs e VRT associados ao diagnóstico de HP pelo CCD. O nível de significância estatística adotado foi 5%. Resultados Foram incluídos noventa e cinco pacientes. A análise de Bland-Altman análise revelou um viés de 8,03 mmHg (IC 95%: -34,9 a 50,9) na PAPs e -3,30 mmHg (IC 95%: -15,9 a 9,3) na PAD. AUC da PAPs e VRT medidas pelo ETT para a discriminação de provável HP foram de 0,936 (IC 95%: 0,836 a 1,0) e 0,919 (IC 95%: 0,837 a 1,0), respectivamente. Entretanto, apenas 33,4% da estimativa ecocardiográfica da PAPs e 55,1% da PAD foram precisas, em comparação às medições obtidas pelo CCD. Conclusão O ETT tem um alto poder discriminatório como método diagnóstico de triagem para HP, apesar de apresentar discordâncias entre os valores absolutos de PAPs e PAD, em comparação às medições por CCD.


Abstract Background The transthoracic echocardiogram (TTE) plays a screening role in the diagnostic algorithm of pulmonary hypertension (PH). Studies have shown a significant disagreement between TTE measurements of the systolic pulmonary artery pressure (sPAP) and right atrial pressure (RAP) and those obtained by right heart catheterization (RHC). Objective To compare TTE measurements of sPAP and RAP with those obtained by RHC in patients being investigated for PH. Methods Patients referred to a PH reference center with a high or intermediate TTE probability of PH upon admission were submitted to RHC. The agreement between sPAP and RAP from both procedures was assessed through the Bland-Altman test. Differences of up to 10 mmHg for sPAP and 5 mmHg for RAP were considered within the variability of the test. Receiver Operating Characteristic (ROC) curve was constructed to determine the most accurate sPAP and Tricuspid regurgitation maximal velocity (TRV)values associated with the diagnosis of PH by RHC. The adopted level of statistical significance was 5%. Results Ninety-five patients were included. The Bland-Altman analysis showed a bias of 8.03 mmHg (95% CI:-34.9-50.9) for sPAP and -3.30 mmHg (95% CI:-15.9-9.3) for RAP. AUC for sPAP and TRV measured by TTE for discrimination of probable PH were 0.936 (95% CI: 0.836-1.0) and 0.919 (95% CI: 0.837-1.0), respectively. However, only 33.4% of the echocardiographic estimate of sPAP and 55.1% of RAP were accurate, as compared to the measurements obtained by RHC. Conclusion TTE has a high discriminatory power as a screening diagnostic method for PH despite presenting disagreements between sPAP and RAP absolute values when compared to RHC measurements.

7.
PLoS One ; 17(5): e0268839, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35622825

RESUMO

Heart rate recovery in 1 minute (HRR1) after the end of the 6-minute walk test (6MWT) is a non-invasive method of determining autonomic dysfunction. This parameter remains largely unexplored in pulmonary arterial hypertension (PAH) registries. We aimed to define the cut-off value and accuracy for abnormal HRR1 after the 6MWT and to investigate the association between HRR1 and clinical worsening in patients with PAH. This composite outcome was defined as first occurrence of all-cause death OR hospitalization from any cause OR disease progression characterized by decreased ≥ 15% in six-minute walking distance from baseline AND start of new specific PAH treatment or persistent worsening of World Health Organization functional class (WHO-FC). We performed a prospective cohort study that included 102 consecutive patients with PAH confirmed by right heart catheterization that underwent an 6MWT upon the diagnosis, recruited from September 2004 to April 2020 and followed up until April 2021 or death. The median HRR1 was 18 beats (IQR: 10-22), 50 and 52 PAH patients with <18 beats and ≥18 beats, respectively. The best cut-off for HRR1 to discriminate clinical worsening was 17 beats, with area under the curve (AUC) of 0.704 (95%CI: 0.584-0.824). The internal validation model by bootstrap showed an AUC of 0.676 (95%CI: 0.566-0.786) and the most accurate value was obtained in the seventh year of follow-up (AUC = 0.711; 95%CI: 0.596-0.844). Patients with an HRR1 <18 beats at baseline had a median event-free time of 2.17 years (95%CI: 1.82 to 2.52) versus 4.75 years (95%CI: 1.43 to 8.07) from those with ≥18 beats. In conclusion, a HRR1 value of less than 18 beats may be a reliable indicator of poor prognosis in patients with PAH.


Assuntos
Hipertensão Arterial Pulmonar , Hipertensão Pulmonar Primária Familiar , Frequência Cardíaca/fisiologia , Humanos , Prognóstico , Estudos Prospectivos , Hipertensão Arterial Pulmonar/diagnóstico , Teste de Caminhada/métodos
8.
ACS Appl Bio Mater ; 5(3): 1025-1037, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35176855

RESUMO

The development of high-performance anti-biofouling surfaces is paramount for controlling bacterial attachment and biofilm growth in biomedical devices, food packing, and filtration membranes. Cellulose nanocrystals (CNCs), a carbon-nanotube-like nanomaterial, have emerged as renewable and sustainable antimicrobial agents. However, CNCs inactivate bacteria under contact-mediated mechanisms, limiting its antimicrobial property mostly to the attached bacteria. This study describes the combination of CNCs with silver nanoparticles (CNC/Ag) as a strategy to increase their toxicity and anti-biofouling performance. CNC/Ag-coated surfaces inactivated over 99% of the attached Escherichia coli and Bacillus subtilis cells compared to 66.9 and 32.9% reduction shown by the pristine CNC, respectively. CNC/Ag was also very toxic to planktonic cells, displaying minimal inhibitory of 25 and 100 µg/mL against B. subtilis and E. coli, respectively. CNC/Ag seems to inactivate bacteria through an "attacking-attacking" mechanism where CNCs and silver nanoparticles play different roles. CNCs can kill bacteria by piercing the cell membrane. This physical membrane stress-mediated mechanism is demonstrated as lipid vesicles release their encapsulated dye upon contact with CNCs. Once the cell membrane is punctured, silver ions can enter the cell passively and compromise the integrity of DNA and other organelles. Inside the cells, Ag+ may damage the cell membrane by selectively interacting with sulfur and nitrogen groups of enzymes and proteins or by harming DNA via accumulation of reactive oxygen species. Therefore, CNC/Ag toxicity seems to combine the puncturing effect of the needle-like CNC and the silver's ability to impair the cell membrane and DNA functionalities.


Assuntos
Incrustação Biológica , Nanopartículas Metálicas , Incrustação Biológica/prevenção & controle , Celulose/farmacologia , Escherichia coli , Nanopartículas Metálicas/química , Prata/farmacologia
9.
Int J Biol Macromol ; 193(Pt A): 647-660, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34699900

RESUMO

In spite of the increasing amount of literature on the production and application of lignin nanoparticles (LNPs), little or no attention has been paid so far to the influence of different production methods on the properties of these nanostructures. Herein, we propose a comprehensive study to assess the impact of several factors on the color, morphology, colloidal stability, antioxidant capacity, and UV-shielding performance of LNPs. LNPs were obtained by two different routes: a bottom-up approach based on the self-assembly in a solvent-antisolvent system with acetone/lignin/water; or a top-down approach based on the ultrasonication of never-dried lignin aqueous suspensions. The starting lignin was extracted from elephant grass leaves or stems, so that the influence of anatomical origin and molecular weight could also be investigated. Moreover, lignin was oxidized prior to being converted into LNPs, allowing for comparisons between different oxidation degrees. This study showed that interesting properties of LNPs can be easily tailored and combined focusing on the various applications of these versatile nanostructures. In a model application, different types of LNPs were incorporated into poly(vinyl alcohol)-based nanocomposites, modulating the UV-protection capability of the polymer matrix.


Assuntos
Lignina/química , Nanopartículas/química , Antioxidantes , Oxirredução , Solventes/química , Ultrassom
10.
Front Cell Infect Microbiol ; 11: 638852, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816341

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged in December 2019 and rapidly outspread worldwide endangering human health. The coronavirus disease 2019 (COVID-19) manifests itself through a wide spectrum of symptoms that can evolve to severe presentations as pneumonia and several non-respiratory complications. Increased susceptibility to COVID-19 hospitalization and mortality have been linked to associated comorbidities as diabetes, hypertension, cardiovascular diseases and, recently, to obesity. Similarly, individuals living with obesity are at greater risk to develop clinical complications and to have poor prognosis in severe influenza pneumonia. Immune and metabolic dysfunctions associated with the increased susceptibility to influenza infection are linked to obesity-associated low-grade inflammation, compromised immune and endocrine systems, and to high cardiovascular risk. These preexisting conditions may favor virological persistence, amplify immunopathological responses and worsen hemodynamic instability in severe COVID-19 as well. In this review we highlight the main factors and the current state of the art on obesity as risk factor for influenza and COVID-19 hospitalization, severe respiratory manifestations, extrapulmonary complications and even death. Finally, immunoregulatory mechanisms of severe influenza pneumonia in individuals with obesity are addressed as likely factors involved in COVID-19 pathophysiology.


Assuntos
Peso Corporal , COVID-19/imunologia , Imunidade , Influenza Humana/imunologia , Obesidade/imunologia , Adipocinas , Tecido Adiposo , Animais , COVID-19/fisiopatologia , Comorbidade , Diabetes Mellitus , Endotoxemia , Fatores de Risco de Doenças Cardíacas , Hospitalização , Humanos , Hiperglicemia , Inflamação , Influenza Humana/fisiopatologia , Síndrome Metabólica , Obesidade/complicações , Infecções por Orthomyxoviridae/imunologia , Fatores de Risco , SARS-CoV-2
12.
Carbohydr Polym ; 256: 117510, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483031

RESUMO

Cellulose nanofibers (CNF) are renewable and biodegradable nanomaterials with attractive barrier, mechanical and surface properties. In this work, three different recombinant enzymes: an endoglucanase, a xylanase and a lytic polysaccharide monooxygenase, were combined to enhance cellulose fibrillation and to produce CNF from sugarcane bagasse (SCB). Prior to the enzymatic catalysis, SCB was chemically pretreated by sodium chlorite and KOH, while defibrillation was accomplished via sonication. We obtained much longer (µm scale length) and more thermostable (resisting up to 260 °C) CNFs as compared to the CNFs prepared by TEMPO-mediated oxidation. Our results showed that a cooperative action of the set of hydrolytic and oxidative enzymes can be used as a "green" treatment prior to the sonication step to produce nanofibrillated cellulose with advanced properties.


Assuntos
Celulase/química , Celulose/química , Endo-1,4-beta-Xilanases/química , Oxigenases de Função Mista/química , Nanofibras/química , Biocatálise , Biodegradação Ambiental , Cloretos/química , Óxidos N-Cíclicos/química , Química Verde , Humanos , Hidrólise , Hidróxidos/química , Nanofibras/ultraestrutura , Oxirredução , Polissacarídeos/química , Compostos de Potássio/química , Saccharum/química , Sonicação
13.
Bioresour Technol ; 321: 124499, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33310387

RESUMO

To maximize the sugar release from sugarcane bagasse, a high-resolution Fractional Factorial Design (FFD) was combined with a Central Composite Orthogonal (CCO) design to simultaneously evaluate a wide range of variables for alkaline pretreatment (NaOH: 0.1-1 mol/L, temperature: 100-220 °C, and time: 20-80 min) and enzymatic saccharification (enzyme loading: 2.5-17.5%, and reaction volume: 550-850 µL). A total of 46 experimental conditions were evaluated and the maximum sugar yield (423 mg/g) was obtained after 18 h enzymatic hydrolysis under optimized conditions (0.25 mol/L NaOH at 202 °C for 40 min, with 12.5% of enzyme loading). Biomass compositional analyses showed that the pretreatments strongly removed lignin (up to 70%), silica (up to 80%) and promoted cellulose enrichment (25-110%). This robust design of experiments resulted in maximizing enzymatic hydrolysis efficiency of sugarcane bagasse and further indicated that this combined approach is versatile for other lignocellulosic biomasses.


Assuntos
Saccharum , Celulose , Hidrólise , Lignina
14.
Front Immunol ; 11: 608883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362796

RESUMO

Pulmonary arterial hypertension (PAH) is a disease of the lung blood vessels that results in right heart failure. PAH is thought to occur in about 5% to 10% of patients with hepatosplenic schistosomiasis, particularly due to S. mansoni. The lung blood vessel injury may result from a combination of embolization of eggs through portocaval shunts into the lungs causing localized Type 2 inflammatory response and vessel remodeling, triggering of autonomous pathology that becomes independent of the antigen, and high cardiac output as seen in portopulmonary hypertension. The condition is likely underdiagnosed as there is little systematic screening, and risk factors for developing PAH are not known. Screening is done by echocardiography, and formal diagnosis requires invasive right heart catheterization. Patients with Schistosoma-associated PAH show reduced functional capacity and can be treated with pulmonary vasodilators, which improves symptoms and may improve survival. There are animal models of this disease that might help in understanding disease pathogenesis and identify novel targets to screen and treatment. Pathogenic mechanisms include Type 2 immunity and activation and signaling in the TGF-ß pathway. There are still major uncertainties regarding Schistosoma-associated PAH development, course and treatment.


Assuntos
Hipertensão Arterial Pulmonar/patologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/patologia , Animais , Humanos , Pulmão/imunologia , Pulmão/patologia , Hipertensão Arterial Pulmonar/imunologia , Esquistossomose mansoni/imunologia , Fator de Crescimento Transformador beta/imunologia , Remodelação Vascular/imunologia , Remodelação Vascular/fisiologia
15.
J Patient Rep Outcomes ; 4(1): 43, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32504261

RESUMO

BACKGROUND: Pulmonary Hypertension (PH) impacts negatively on patients' health-related quality of life (HRQoL). The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) was the first PH-specific and validated instrument for use in different languages worldwide. This report describes the adaptation and psychometric validation of the CAMPHOR into Brazilian Portuguese language. METHODS: The translation and validation process included a bilingual and lay panel translation; cognitive debriefing interviews; psychometric testing in two repeated times assessing internal consistency, reproducibility and validity of the questionnaire. The Nottingham Health Profile (NHP) questionnaire was used as a comparator to test for convergent validity. RESULTS: The translation captured the same concepts as the English questionnaire and produced a comprehensive instrument in a Brazilian-Portuguese version expressing common, natural language. The psychometric evaluation involved 102 patients (48.8 ± 14.5 years, 80,4% female]. Cronbach's alpha coefficients were above 0.9 on all three CAMPHOR scales. There was excellent test-retest reliability (coefficients above 0.85 on all scales). CAMPHOR Symptoms scale and Activities scale correlated highly with Physical Mobility section and CAMPHOR QoL scale was strongly associated with the Emotional Reactions and Social Isolation sections of NHP. There was a significant association between gender and perceived general health (p < 0.05). There were significant differences in CAMPHOR scale scores between patients who differed according to their perceived disease severity and general health. CONCLUSIONS: The present CAMPHOR version demonstrated good psychometric properties and provides a reliable instrument for assessing HRQL and QoL in Brazilian PH patients, addressing patients' perspective of their illness in a comprehensive way.

16.
Carbohydr Polym ; 218: 145-153, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31221315

RESUMO

In this work, cellulose nanofibers (CNF) were obtained from sugarcane bagasse (SC) without high-energy mechanical treatments, using TEMPO-mediated oxidation. Variable NaClO concentrations were used to impart electrostatic repulsion between surface charged groups thus facilitating fibril separation. CNFs with diameters in the 3-5 nm range were obtained by oxidation of SC pulp with NaClO at 25 and 50 mmol/g. After a 30 min -sonication step, these CNFs were broken down into cellulose nanocrystals (CNC) by mechanical action. Both CNF and CNC preparation by this method are possible in SC due to its particular cell wall morphology and were not achieved in eucalyptus biomass, which is more recalcitrant. This work provided thus a new pathway to modulate the final morphology of cellulose particles by combining a low recalcitrant raw material with different surface charge densities.

17.
Biotechnol Biofuels ; 11: 206, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30061928

RESUMO

BACKGROUND: Pretreatments are one of the main bottlenecks for the lignocellulose conversion process and the search for cheaper and effective pretreatment methodologies for each biomass is a complex but fundamental task. Here, we used a 2ν5-1 fractional factorial design (FFD) to optimize five pretreatment variables: milling time, temperature, double treatment, chemical concentration, and pretreatment time in acid-alkali (EA) and acid-organosolv (EO) pretreatments, applied to elephant grass leaves. RESULTS: FFD allowed optimization of the pretreatment conditions using a reduced number of experiments and allowed the identification of secondary interactions between the factors. FFD showed that the temperature can be kept at its lower level and that the first acid step can be eliminated in both pretreatments, without significant losses to enzymatic hydrolysis. EA resulted in the highest release of reducing sugars (maximum of 205 mg/g substrate in comparison to 152 mg/g in EO and 40 mg/g in the untreated sample), using the following conditions in the alkali step: [NaOH] = 4.5% w/v; 85 °C and 100 min after ball milling the sample. The factors statistically significant (P < 0.05) in EA pretreatment were NaOH concentration, which contributes to improved hydrolysis by lignin and silica removal, and the milling time, which has a mechanical effect. For EO samples, the statistically significant factors to improved hydrolysis were ethanol and catalyst concentrations, which are both correlated to higher cellulose amounts in the pretreated substrates. The catalyst is also correlated to lignin removal. The detailed characterization of the main hemicellulosic sugars in the solids after pretreatments revealed their distinct recalcitrance: glucose was typically more recalcitrant than xylose and arabinose, which could be almost completely removed under specific pretreatments. In EA samples, the removal of hemicellulose derivatives was very dependent on the acid step, especially arabinose removal. CONCLUSION: The results presented herewith contribute to the development of more efficient and viable pretreatments to produce cellulosic ethanol from grass biomasses, saving time, costs and energy. They also facilitate the design of enzymatic cocktails and a more appropriate use of the sugars contained in the pretreatment liquors, by establishing the key recalcitrant polymers in the solids resulting from each processing step.

18.
Rev. Pesqui. Fisioter ; 8(1): 94-100, fev., 2018. ilus, tab
Artigo em Inglês, Português | LILACS | ID: biblio-912795

RESUMO

Introdução: As neoplasias malignas, leucemias e linfomas, são responsáveis por alterar o metabolismo dos pacientes, atrelado a isso, o tempo de internamento hospitalar prolongando em conjunto com os tratamentos antineoplásicos impactam na qualidade de vida dos pacientes oncológicos. Objetivo: Avaliar a qualidade de vida de pacientes oncológicos em tratamento quimioterápico durante internamento hospitalar. Materiais e métodos: Estudo analítico, longitudinal e observacional, com 15 pacientes internados em hospital público, de grande porte, e alta complexidade, no período de fevereiro a julho de 2017. A coleta de dados ocorreu em três etapas: primeiro, quinto e décimo dia de internamento utilizando o questionário Fact-d. Resultados: No período de realização do estudo, 56 pacientes foram internados na enfermaria 1B do HUPES. Desses, 25 pacientes foram considerados elegíveis. Após o início do estudo, ocorreram 10 altas antes do décimo dia, totalizando uma amostra final de 15 pacientes. A idade variou de 20 a 66 anos, sendo que a mediana, em anos, foi de 31 (35,80 16,61), 53% foram do sexo feminino. Quanto ao tipo de câncer, 53% tinham leucemia. Durante o tempo de internamento, não foi observada diferença significativa da qualidade de vida entre o primeiro, quinto e décimo dia de internamento hospitalar. Conclusão: Apesar dos pacientes estarem hospitalizados, a qualidade de vida manteve-se relativamente preservada. [AU]


Background: Muscle weakness can be acquired through chemotherapy, radiotherapy and length of stay impacting overall muscle strength and quality of life of oncology patients. Objective: To evaluate global muscle strength and quality of life in cancer patients during hospitalization. Methods: Analytical, longitudinal and observational study with 15 patients admitted to a public hospital from February to July 2017. Data collection took place in three stages: first, fifth and tenth day of hospitalization. Results: Age ranged from 20 to 66 years, and the median, in years, was 31 (35.80 + 16.61), 53% were female. Regarding the type of cancer, 53% with leukemia and 47% with lymphoma. During the hospitalization time, no significant difference in overall muscle strength and quality of life was observed between the first, fifth and tenth days of hospitalization. Conclusion: Although patients were hospitalized, overall muscle strength and quality of life remained relatively undamaged. [AU]


Assuntos
Leucemia , Linfoma , Neoplasias , Qualidade da Assistência à Saúde
19.
Carbohydr Polym ; 180: 38-45, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29103518

RESUMO

This work is focused in methodologies to obtain cellulose nanocrystals, cellulose nanofibrils, soluble lignin and fermentable sugars from elephant grass, aiming a more integral use of this biomass. To improve hydrolysis, three different pretreatments for biomass delignification and bleaching were compared: 1. Concentrated alkaline peroxide (CP); 2. Diluted alkaline peroxide (DP); and 3. Acid-alkali (AA) pretreatment. Cellulose nanocrystals were obtained from elephant grass leaves by acid hydrolysis, with a 12-16% w/w yield considering the initial biomass weight, and presented high crystallinity index (CI=72-77%) and aspect ratios (30-44), depending on the pretreatment approach. Together with the cellulose nanocrystals, other useful by-products were obtained, such as cellulose nanofibrils (3.8%-9.7% w/w yield), extractives (12.3%), liquors rich in hydrolysed lignin (16.0-21.1%) and sugars (22.1-25.2%). The results presented herewith should contribute to the economic viability and the sustainability of this biomass fractionation process.


Assuntos
Celulose/química , Nanofibras/química , Nanopartículas/química , Pennisetum/química , Açúcares/química , Biocombustíveis , Fermentação
20.
Rev. bras. cancerol ; 64(4): 533-539, 2018.
Artigo em Português | LILACS | ID: biblio-1025287

RESUMO

Introdução: As neoplasias hematológicas, leucemias e linfomas são patologias que afetam o sangue ou tecidos formadores dele. Durante o período de hospitalização, os pacientes podem desenvolver redução da capacidade funcional que pode interferir na sua função respiratória. Objetivo: Avaliar a influência do tempo de internamento sobre a força muscular respiratória e o nível funcional de adultos com leucemia e linfoma. Método: Estudo observacional, com delineamento longitudinal e abordagem quantitativa, realizado na enfermaria onco-hematológica do Complexo Hospitalar Universitário Professor Edgard Santos (Hupes). A avaliação da força muscular respiratória foi mensurada pelo manovacuômetro e a capacidade funcional pela escala de desempenho de Karnofsky (KPS). Resultados: No decorrer do tempo de internamento dos pacientes, houve uma diminuição da pressão expiratória máxima (PEM) (p=0,000), porém não foi observada diferença significativa na pressão inspiratória máxima (PIM) (p>0,05). Em relação à KPS, os pacientes apresentaram nível de funcionalidade de 70%. Conclusão: Este estudo demonstrou que a PEM foi alterada durante o internamento, porém não houve modificação da PIM e da funcionalidade dos pacientes.


Introduction: Hematologic neoplasms, leukemias and lymphomas are pathologies that affect the blood or tissues that form it. During the hospitalization period patients may develop functional capacity reduction, which may interfere with their respiratory function. Objective: Evaluate the influence of hospitalization time about respiratory muscle strength and functional level of adults with leukemia and lymphoma. Method: Observational study, with longitudinal design and quantitative approach, performed at the onco-hematological ward of the University Hospital Complex Professor Edgard Santos (Hupes). The assessment of respiratory muscle strength was measured using the manovacuometer and functional capacity using the Karnofsky Performance Scale (KPS). Results: During the hospitalization time, there was a decrease in the maximum expiratory pressure (PEM) (p=0.000), but no significant difference was observed in the maximum inspiratory pressure (PIM) (p>0.05). In relation to KPS, the patients presented functional level of 70%. Conclusion: This study demonstrated that PEM was altered during hospitalization, but there was no modification of the PIM and the functionality of the patients.


Introducción: Las neoplasias hematológicas, leucemias y linfomas son patologías que afectan a la sangre o tejidos formadores de él. Durante el período de hospitalización los pacientes pueden desarrollar una reducción de la capacidad functional, que puede interferer en su función respiratoria. Objetivo: Evaluar la influencia del tiempo de internamiento sobre la fuerza muscular respiratoria y nivel funcional de adultos con leucemia y linfoma. Método: Estudio observacional, con delineamiento longitudinal y el enfoque cuantitativo, realizado en la enfermería onco-hematológica del Complejo Hospitalario Universitario Profesor Edgard Santos (Hupes). La evaluación de la fuerza muscular respiratoria se midió utilizando el manovacuómetro y la capacidad funcional utilizando la escala de rendimiento de Karnofsky (KPS). Resultados: En el transcurso del tiempo de internamiento de los pacientes, hubo una disminución de la presión espiratoria máxima (PEM) (p=0,000), pero no se observó diferencia significativa en la presión inspiratoria máxima (PIM) (p>0,05). En relación a KPS, los pacientes presentaron un nivel de funcionalidad del 70%. Conclusión: Este estudio demostró que la PEM fue alterada durante el internamiento, pero no hubo modificación de la PIM y de la funcionalidad de los pacientes.


Assuntos
Humanos , Masculino , Feminino , Adulto , Leucemia/metabolismo , Neoplasias Hematológicas/complicações , Linfoma/metabolismo , Avaliação de Estado de Karnofsky , Força Muscular , Tempo de Internação
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