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Glycerol is a common by-product of industrial biodiesel syntheses. Due to its properties, availability, and versatility, residual glycerol can be used as a raw material in the production of high value-added industrial inputs and outputs. In particular, products like hydrogen, propylene glycol, acrolein, epichlorohydrin, dioxalane and dioxane, glycerol carbonate, n-butanol, citric acid, ethanol, butanol, propionic acid, (mono-, di-, and triacylglycerols), cynamoil esters, glycerol acetate, benzoic acid, and other applications. In this context, the present study presents a critical evaluation of the innovative technologies based on the use of residual glycerol in different industries, including the pharmaceutical, textile, food, cosmetic, and energy sectors. Chemical and biochemical catalysts in the transformation of residual glycerol are explored, along with the factors to be considered regarding the choice of catalyst route used in the conversion process, aiming at improving the production of these industrial products., (© 2021 International Union of Biochemistry and Molecular Biology, Inc.)

A review on the enzyme β-galactosidase from Kluyveromyces lactis is presented, from the perspective of its structure and mechanisms of action, the main catalyzed reactions, the key factors influencing its activity, and selectivity, as well as the main techniques used for improving the biocatalyst functionality. Particular attention was given to the discussion of hydrolysis, transglycosylation, and galactosylation reactions, which are commonly mediated by this enzyme. In addition, the products generated from these processes were highlighted. Finally, biocatalyst improvement techniques are also discussed, such as enzyme immobilization and protein engineering. On these topics, the most recent immobilization strategies are presented, emphasizing processes that not only allow the recovery of the biocatalyst but also deliver enzymes that show better resistance to high temperatures, chemicals, and inhibitors. In addition, genetic engineering techniques to improve the catalytic properties of the β-galactosidases were reported. This review gathers information to allow the development of biocatalysts based on the β-galactosidase enzyme from K. lactis, aiming to improve existing bioprocesses or develop new ones., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

This study evaluated the syringe/needle (SN), passive ultrasonic irrigation (PUI) and XP-endo Finisher (XP) in the removal of Ca(OH) 2 -based paste and the bond strength (BS) values of an epoxy resin (AH Plus) and silicate (MTA)-based sealers to root dentin. Eighty lower premolars were assigned: control group (CT), SN, PUI and XP, and subdivided according to the sealer (n = 10) for BS. SN has the lowest removal followed by PUI and XP. AH Plus had higher BS for CT compared with SN in all root thirds. CT and XP presented similar BS in the apical and middle thirds and higher than SN and PUI. For MTA, similar BS was observed in the cervical and apical thirds, and in the middle third, CT, PUI and XP presented similar values and higher than SN. PUI and XP methods presented higher efficiency in the Ca(OH) 2 removal, and the residual Ca(OH) 2 provides a reduction in BS of the AH Plus., (© 2020 Australian Society of Endodontology Inc.)

Twenty-seven Nellore cow-calf pairs were submitted for feed efficiency testing. The animals were weighed every 21 ± 5 days to obtain metabolic body weight (BW 0.75 ) and average daily gain (ADG). Subcutaneous fat thickness (SFT; at 20, 83, 146, and 176 days post-calving); milk yield and components (63, 85, and 151 days); levels of glucose, cholesterol, triglycerides, β-hydroxybutyrate, albumin, urea, creatinine, calcium, phosphorus, magnesium, insulin, and cortisol (15, 41, 62, and 124 days); and ingestive behavior were evaluated. Residual feed intake was calculated for the first stage (RFI1; 21 to 100 days post-calving) and the second stage of lactation (RFI2; 100 to 188 days post-calving), and the cows were classified based on RFI1 as most efficient (RFI1 < 0) and least efficient (RFI1 > 0). Negative RFI1 cows consumed 1.3 kg/day of dry matter, or 9.77%, less than positive RFI1 cows. Most- and least-efficient cows did not differ in terms of subcutaneous fat thickness traits and milk yield or energy-corrected milk (ECM). Glucose (P = 0.0785), triglycerides (P = 0.0795), and phosphorus (P = 0.0597) concentrations were higher in the first stage of lactation in most-efficient cows. Maternal characteristics such as calf weight at birth and at 205 days and ADG were similar in most- and least-efficient cows. The most-efficient cows are more economic as they consume less feed for the same level of production.

Trypanosoma cruzi trypomastigotes continuously shed into the medium plasma membrane fragments sealed as vesicles enriched in glycoproteins of the gp85 and trans-sialidase (TS) superfamily and alpha-galactosyl-containing glycoconjugates. Injection of a vesicle fraction into BALB/c mice prior to T. cruzi infection led to 40% of deaths on the 16thday post-infection and 100% on day 20th whereas 20% of untreated animals survived for more than 30days. The vesicle-treated animals developed severe heart pathology, with intense inflammatory reaction and higher number of amastigote nests. Analysis of the inflammatory infiltrates 15days after infection showed predominance of TCD4(+) lymphocytes and macrophages, but not of TCD8(+) cells, as well as a decrease of areas labeled with anti-iNOS antibodies as compared to the control. Higher levels of IL-4 and IL-10 mRNAs were found in the hearts and higher IL-10 and lower NO levels in splenocytes of vesicles pretreated animals. Treatment of mice with neutralizing anti-IL-10 or anti-IL-4 antibodies precluded the effects of pre-inoculation of membrane vesicles on infection. These results indicate that T. cruzi shed membrane components increase tissue parasitism and inflammation by stimulation of IL-4 and IL-10 synthesis and thus may play a central role in the pathogenesis of Chagas' disease acute phase.

The authors analyze the result of Shouldice inguinal hernia repair in 1000 patients. In a total of 1034 hernias, 966 of them were unilateral and 68 bilateral. The hernias were indirect (61.7%), direct (24.9%) and combined (3.5%). There were 102 recurrent hernias (9.9%) and the mean age of the patients was 50 years. In most cases the patients were male (96.9%) and peasants (47.6%). The post-operative follow-up was annual in 65.8% of the patients, for a period up to 10 years. The recurrence rate was 0.8% in the cases of primary hernias and 4.9% in the case of recurrent ones.