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1.
Int J Dermatol ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411257

RESUMO

BACKGROUND: Clobetasol has demonstrated remarkable results in treating melasma within a short time frame; however, its use is limited because of the risk of local side effects. To date, there is no controlled trial on sequential clobetasol/hydroquinone for melasma. This study aimed to investigate the tolerability and efficacy of 0.05% clobetasol followed by 4% hydroquinone (CLOB-HQ) in comparison to the isolated use of 4% hydroquinone (HQ). METHODS: A double-blinded, randomized clinical trial involving 50 women with facial melasma was performed. They were directed to apply 0.05% clobetasol every night for 14 days, followed by 4% hydroquinone for 46 days (CLOB-HQ group), or the use of hydroquinone for 60 days (HQ group). Evaluations were carried out at inclusion, and after 14 and 60 days of treatment, measuring modified Melasma Area and Severity Index (mMASI), Melasma Quality of Life scale (MELASQoL), and colorimetry. The Global Aesthetic Improvement Scale (GAIS) was assessed by a blinded evaluator. RESULTS: There was no difference in the main outcomes at D14 and D60 (P > 0.1). For CLOB-HQ, the mean (CI 95%) reduction in mMASI was 13.2% (5.1-21.3%) and 43.1% (32.2-54.0%) at D14 and D60, and for HQ, they were 10.6% (5.9-27.5%) and 44.8% (33.2-52.3%). The MELASQoL, colorimetric luminosity, and GAIS showed a progressive improvement for both groups despite no difference between them. No severe side effects were identified. No cases of telangiectasias, atrophy, or perioral dermatitis were associated with the use of CLOB. CONCLUSION: The sequential CLOB-HQ regimen was safe and well tolerated, even though its efficacy was not different from HQ after 14 or 60 days of treatment. Based on these findings, the use of clobetasol 14 days before hydroquinone is not advisable for the treatment of melasma.

3.
3 Biotech ; 11(10): 432, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34603910

RESUMO

Alkaline sulfite pretreated sugarcane bagasse was enzymatically hydrolyzed in a packed-bed column reactor and a bubble column reactor was evaluated to produce ethanol from the hydrolysate. Initial solid loadings of 9-16% were used in column reactor in the hydrolysis step, and the use of lower value (9%) resulted in 41 g L-1 of glucose in the hydrolysate, corresponding to 87% of cellulose hydrolysis yield. This yield was reduced to 65% for a solid loading of 16%, corresponding to a glucose concentration of 54 g L-1. Subsequently, Saccharomyces cerevisiae and Scheffersomyces stipitis were used for ethanol production in medium based on hydrolysate previously obtained, using different aeration flowrates (0.3, 0.5 and 0.7 vvm). In simple batch fermentation using S. cerevisiae, higher ethanol yield (0.40 g.g-1) and productivity (1.58 g.L-1.h-1) were achieved using 0.5 vvm. When S. stipitis was used in simple batch co-fermentations, the maximum ethanol productivities were obtained using 0.5 and 0.7 vvm (0.64 and 0.63 g.L-1.h-1, respectively). Successive repeated batches resulted in average ethanol concentration of 38 g.L-1 and fermentation efficiency of 82%, when using S. cerevisiae. For S. stipitis, those values were, respectively, 36 g.L-1 and 50%, with volumetric productivity increased along the cycles. Thus, the potential of the bioreactors as simple systems for use in the biological steps of biorefineries was demonstrated. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02932-3.

4.
J Surg Oncol ; 121(5): 814-822, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31898327

RESUMO

INTRODUCTION: Considering the high morbimortality rate in oncologic surgeries of the gastrointestinal tract, especially in patients with malnutrition, the use of predictive tools is necessary, since preoperative strategies could improve postoperative outcomes. OBJECTIVES: To evaluate body composition by computed tomography and its association with morbimortality post esophagectomy and total gastrectomy. METHODS: Prospective cohort study (n = 80). Sociodemographic, diagnostic, treatment and postoperative data were collected. Anthropometric and biochemical (hemoglobin, transferrin, and albumin) data were evaluated. The muscle mass was calculated through two methods, the muscle mass index (MMI) and the psoas total area (PTA). For postoperative complications classification, the Clavien-Dindo scale was used. RESULTS: The prevalence of muscle depletion found was 33.8% by MMI and 61% by PTA (poor agreement, kappa = 0.25). Complication rates were 18.5% in gastrectomies and 50% in esophagectomies. No statistically significant difference was found between the presence of muscle depletion and complications. However, when stratified by surgery, a borderline association was found between the MMI and post esophagectomies complications (P = .05). CONCLUSION: Despite the high prevalence of muscle loss, it was not possible to correlate it with surgical outcomes for gastrectomies, but for esophagectomies, there may be relevance due to borderline association, although patients received nutritional therapy.


Assuntos
Composição Corporal , Esofagectomia/efeitos adversos , Gastrectomia/efeitos adversos , Sarcopenia/diagnóstico por imagem , Estudos de Coortes , Feminino , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Complicações Pós-Operatórias , Prognóstico , Albumina Sérica , Tomografia Computadorizada por Raios X , Transferrina/análise
5.
Bioresour Technol ; 190: 242-50, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25958148

RESUMO

This study evaluated the viability of n-butanol production integrated within a first and second generation sugarcane biorefinery. The evaluation included a deterministic analysis as well as a stochastic approach, the latter using Monte Carlo simulation. Results were promising for n-butanol production in terms of revenues per tonne of processed sugarcane, but discouraging with respect to internal rate of return (IRR). The uncertainty analysis determined there was high risk involved in producing n-butanol and co-products from ethanol catalysis. It is unlikely that these products and associated production route will be financially attractive in the short term without lower investment costs, supportive public policies and tax incentives coupled with biofuels' production strategies.


Assuntos
1-Butanol/metabolismo , Biocombustíveis/microbiologia , Reatores Biológicos/microbiologia , Etanol/metabolismo , Modelos Estatísticos , Saccharum/microbiologia , 1-Butanol/isolamento & purificação , Catálise , Simulação por Computador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Bioresour Technol ; 142: 390-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23748087

RESUMO

This paper presents the techno-economics of greenfield projects of an integrated first and second-generation sugarcane biorefinery in which pentose sugars obtained from sugarcane biomass are used either for biogas (consumed internally in the power boiler) or n-butanol production via the ABE batch fermentation process. The complete sugarcane biorefinery was simulated using Aspen Plus®. Although the pentoses stream available in the sugarcane biorefinery gives room for a relatively small biobutanol plant (7.1-12 thousand tonnes per year), the introduction of butanol and acetone to the product portfolio of the biorefinery increased and diversified its revenues. Whereas the IRR of the investment on a biorefinery with biogas production is 11.3%, IRR varied between 13.1% and 15.2% in the butanol production option, depending on technology (regular or engineered microorganism with improved butanol yield and pentoses conversion) and target market (chemicals or automotive fuels). Additional discussions include the effects of energy-efficient technologies for butanol processing on the profitability of the biorefinery.


Assuntos
Biocombustíveis , Biomassa , Butanóis/metabolismo , Custos e Análise de Custo , Pentoses/metabolismo , Saccharum/metabolismo
7.
Bioresour Technol ; 135: 316-23, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23127845

RESUMO

The techno-economics of greenfield projects of a first-generation sugarcane biorefinery aimed to produce ethanol, sugar, power, and n-butanol was conducted taking into account different butanol fermentation technologies (regular microorganism and mutant strain with improved butanol yield) and market scenarios (chemicals and automotive fuel). The complete sugarcane biorefinery with the batch acetone-butanol-ethanol (ABE) fermentation process was simulated using Aspen Plus®. The biorefinery was designed to process 2 million tonne sugarcane per year and utilize 25%, 50%, and 25% of the available sugarcane juice to produce sugar, ethanol, and butanol, respectively. The investment on a biorefinery with butanol production showed to be more attractive [14.8% IRR, P(IRR>12%)=0.99] than the conventional 50:50 (ethanol:sugar) annexed plant [13.3% IRR, P(IRR>12%)=0.80] only in the case butanol is produced by an improved microorganism and traded as a chemical.


Assuntos
Biotecnologia/economia , Biotecnologia/métodos , Butanóis/metabolismo , Química Verde/economia , Química Verde/métodos , Saccharum/metabolismo , Biocombustíveis/economia , Brasil , Simulação por Computador , Custos e Análise de Custo , Fermentação , Investimentos em Saúde , Método de Monte Carlo
8.
Bioresour Technol ; 103(1): 152-61, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22019267

RESUMO

Ethanol production from lignocellulosic materials is often conceived considering independent, stand-alone production plants; in the Brazilian scenario, where part of the potential feedstock (sugarcane bagasse) for second generation ethanol production is already available at conventional first generation production plants, an integrated first and second generation production process seems to be the most obvious option. In this study stand-alone second generation ethanol production from surplus sugarcane bagasse and trash is compared with conventional first generation ethanol production from sugarcane and with integrated first and second generation; simulations were developed to represent the different technological scenarios, which provided data for economic and environmental analysis. Results show that the integrated first and second generation ethanol production process from sugarcane leads to better economic results when compared with the stand-alone plant, especially when advanced hydrolysis technologies and pentoses fermentation are included.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Celulose/química , Etanol/metabolismo , Resíduos de Alimentos , Saccharum/química , Biocombustíveis/economia , Biotecnologia/economia , Celulose/economia , Simulação por Computador , Destilação , Eletricidade , Etanol/economia , Eutrofização , Aquecimento Global
9.
Bioresour Technol ; 102(19): 8964-71, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21795041

RESUMO

Much of the controversy surrounding second generation ethanol production arises from the assumed competition with first generation ethanol production; however, in Brazil, where bioethanol is produced from sugarcane, sugarcane bagasse and trash will be used as feedstock for second generation ethanol production. Thus, second generation ethanol production may be primarily in competition with electricity production from the lignocellulosic fraction of sugarcane. A preliminary technical and economic analysis of the integrated production of first and second generation ethanol from sugarcane in Brazil is presented and different technological scenarios are evaluated. The analysis showed the importance of the integrated use of sugarcane including the biomass represented by surplus bagasse and trash that can be taken from the field. Second generation ethanol may favorably compete with bioelectricity production when sugarcane trash is used and when low cost enzyme and improved technologies become commercially available.


Assuntos
Fontes de Energia Bioelétrica/economia , Biocombustíveis/economia , Celulose/química , Etanol/química , Eliminação de Resíduos/métodos , Brasil , Simulação por Computador
10.
J Ind Microbiol Biotechnol ; 38(8): 955-66, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20838849

RESUMO

Sugarcane bagasse is used as a fuel in conventional bioethanol production, providing heat and power for the plant; therefore, the amount of surplus bagasse available for use as raw material for second generation bioethanol production is related to the energy consumption of the bioethanol production process. Pentoses and lignin, byproducts of the second generation bioethanol production process, may be used as fuels, increasing the amount of surplus bagasse. In this work, simulations of the integrated bioethanol production process from sugarcane, surplus bagasse and trash were carried out. Selected pre-treatment methods followed, or not, by a delignification step were evaluated. The amount of lignocellulosic materials available for hydrolysis in each configuration was calculated assuming that 50% of sugarcane trash is recovered from the field. An economic risk analysis was carried out; the best results for the integrated first and second generation ethanol production process were obtained for steam explosion pretreatment, high solids loading for hydrolysis and 24-48 h hydrolysis. The second generation ethanol production process must be improved (e.g., decreasing required investment, improving yields and developing pentose fermentation to ethanol) in order for the integrated process to be more economically competitive.


Assuntos
Etanol/metabolismo , Saccharum/metabolismo , Biomassa , Biotecnologia/métodos , Celulose/metabolismo , Fontes Geradoras de Energia , Fermentação , Hidrólise , Lignina/metabolismo , Modelos Biológicos , Centrais Elétricas , Resíduos
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