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Polysaccharides are an attractive source for use in dressings due to their plentiful availability, low cost, biodegradability, biocompatibility and multifunctionality. In this work, we describe the preparation, characterization and evaluation of the healing capacity of chitosan films produced via the solvent evaporation method containing β- D -glucan obtained from Rhodotorula mucilaginosa yeast and bromelain extracted from pineapple (Ananas comosus), in free form or incorporated in liposomes or associated with polymeric nanoparticles. The films were characterized according to the swelling degree, thermal stability and enzymatic activity, and in vivo tests were performed to evaluate the films' healing potential. The swelling degree of films with bioactive substances ranged from 110.69% to 185.82%, indicating that the films are suitable for use on non-exudative wounds. The films, when stored in a refrigerator, remained functional and maintained enzymatic activity for up to 30 days. Histopathological results showed the absence of edema, a low amount of inflammatory infiltrate and an increase in angiogenesis during the proliferative phase, with such events possibly involving the action of active compounds in films. The results showed promise for wound healing (wound contraction of 76.37%) using films containing bromelain and beta glucan for seven days. [ABSTRACT FROM AUTHOR]

The utilization of lignocellulosic materials for second-generation ethanol production via enzymatic catalysts is primarily hindered by enzyme cost. Enzymatic immobilization emerges as a viable solution, enabling enzyme reuse. This study investigated the immobilization of an enzymatic extract obtained from Moniliophthora perniciosa fermentation in calcium alginate spheres using the direct trapping method. Initial tests assessed β-glucosidase activity, showing that a higher concentration of calcium chloride (1 M) alongside larger diameter spheres yielded improved results. The immobilized enzyme was reused for up to 17 cycles without significant loss of activity. The percentage of reducing sugars after 48-h hydrolysis with the supplemented enzymatic extract was 226%, doubling the value achieved with only the free enzymatic extract. The immobilized enzyme retained 50% of its initial activity after 1 h at 80 °C, demonstrating higher activity at pH 6 and 60 °C. These findings suggest that this immobilization technique is simple, economically viable, and effective for the hydrolysis of pretreated sugarcane bagasse. Successful immobilization of M. perniciosa enzymatic extract achieved through direct entrapment in calcium alginate. Immobilized β-glucosidase demonstrates sustained activity over 16 reuse cycles, showcasing the potential for cost-effective bioconversion processes. Enhanced hydrolysis of sugarcane bagasse observed with immobilized enzymatic extract, indicating a promising approach for improved biomass utilization. [ABSTRACT FROM AUTHOR]

Background: Candida auris is an emerging multidrug‐resistant yeast, frequently causing outbreaks in health care facilities. The pathogen persistently colonises human skin and inanimate surfaces such as catheters, aiding to its spread. Moreover, colonisation is a risk factor to develop invasive infection. Objectives: We investigated 61 C. auris strains isolated from non‐sterile human body sites (n = 53) and the hospital environment (n = 8), originating from four different centres in a single Brazilian state. Materials and Methods: Antifungal susceptibility testing (AFST) against common antifungals was performed, and resistance‐associated genes were evaluated. Genetic relatedness was investigated with short tandem repeat (STR) genotyping and validated with whole‐genome sequencing (WGS) single nucleotide polymorphism (SNP) analysis. Results: Antifungal susceptibility testing demonstrated that all isolates were susceptible to azoles, echinocandins and amphotericin B. No mutations were detected in ERG11 and FKS1 genes. With STR typing, isolates were allocated to clade IV and appeared closely related. This was confirmed by WGS SNP analysis of 6 isolates, which demonstrated a maximal difference of only 41 SNPs between these strains. Furthermore, the Brazilian isolates formed a distinct autochthonous branch within clade IV, excluding recent introductions from outside the country. A molecular clock analysis of clade IV isolates from various countries suggests that early in the previous century there was a unique event causing environmental spread of a C. auris ancestor throughout the Latin‐American continent, followed by human introduction during the last decades. Conclusion: We report the emergence of C. auris patient colonisation in multiple centres by fluconazole‐susceptible clade IV close‐related strains in Pernambuco State, Brazil. [ABSTRACT FROM AUTHOR]

β-glucosidase is an essential enzyme for the enzymatic hydrolysis of lignocellulosic biomass, as it catalyzes the final stage of cellulose breakdown, releasing glucose. This paper aims to produce β-glucosidase from Saccharomyces cerevisiae and evaluate the enzymatic degradation of delignified sugarcane bagasse. S. cerevisiae was grown in yeast peptone dextrose medium. Partial purification of the enzyme was achieved through precipitating proteins with ethanol, and the optimal activity was measured by optimizing pH and temperature. The effects of ions, glucose tolerance, and heat treatment were evaluated. Delignified sugarcane bagasse was hydrolyzed by the enzyme. β-glucosidase showed a specific activity of 14.0712 ± 0.0207 U mg−1. Partial purification showed 1.22-fold purification. The optimum pH and temperature were 6.24 and 54 °C, respectively. β-glucosidase showed tolerance to glucose, with a relative activity of 71.27 ± 0.16%. Thermostability showed a relative activity of 58.84 ± 0.91% at 90 °C. The hydrolysis of delignified sugarcane bagasse showed a conversion rate of 87.97 ± 0.10% in the presence of Zn2+, an ion that promoted the highest increase in enzymatic activity. S. cerevisiae produced an extracellular β-glucosidase with good stability at pH and temperatures conventionally applied in the hydrolysis of lignocellulosic biomass, showing viability for industrial application. [ABSTRACT FROM AUTHOR]

Objective: To determine reference intervals (RI) for serum immunoglobulin A (IgA) levels in healthy children aged 1 to 1 0 years residing in the central region of Brazil. Methods: This cross-sectional study was conducted on 1,743 healthy children randomly selected from kindergartens and public schools in Cuiaba, MT, Brazil. The IgA RIs were defined using the statistical methods postulated by the guidelines of the United States Clinical and Laboratory Standards Institute, the nonparametric bootstrap method, and Horn's robust method after the correction of discrepancies by Tukey's, Dixon's, and Horn's methods, respectively. The results were defined based on the values contained between the 2.5th and 97.5th percentiles and their respective 95% confidence intervals. Results: Partition by sex was not necessary to determine the IgA RI of the studied children. Homogeneous subgroups were identified among children aged 1-<2, 2-<5, and 5-<11 years, whose IgA-specific RIs were determined. Conclusion: The serum IgA RIs were established for three groups of Brazilian children aged 1-11 years, which differed from those currently applied in Brazilian pediatric practice and from those defined by international studies. This definition will help Brazilian pediatricians formulate an accurate diagnosis and facilitate decision-making. [ABSTRACT FROM AUTHOR]