Lignin degradation by a novel thermophilic and alkaline yellow laccase from Chitinophaga sp.

Laccases (EC 1.10.3.2) are oxidoreductases that belong to the multicopper oxidase subfamily and are classified as yellow/white or blue according to their absorption spectrum. Yellow laccases are more useful for industrial processes since they oxidize nonphenolic compounds in the absence of a redox mediator and stand out for being more stable and functional under extreme conditions. This study aimed to characterize a new laccase that was predicted to be present in the genome of Chitinophaga sp. CB10 - Lac_CB10. Lac_CB10, with a molecular mass of 100.06 kDa, was purified and characterized via biochemical assays using guaiacol as a substrate. The enzyme demonstrated extremophilic characteristics, exhibiting relative activity under alkaline conditions (CAPS buffer pH 10.5) and thermophilic conditions (80-90°C), as well as maintaining its activity above 50% for 5 h at 80°C and 90°C. Furthermore, Lac_CB10 presented a spectral profile typical of yellow laccases, exhibiting only one absorbance peak at 300 nm (at the T2/T3 site) and no peak at 600 nm (at the T1 site). When lignin was degraded using copper as an inducer, 52.27% of the material was degraded within 32 h. These results highlight the potential of this enzyme, which is a novel yellow laccase with thermophilic and alkaline activity and the ability to act on lignin. This enzyme could be a valuable addition to the biorefinery process. In addition, this approach has high potential for industrial application and in the bioremediation of contaminated environments since these processes often occur at extreme temperatures and pH values. IMPORTANCE: The characterization of the novel yellow laccase, Lac_CB10, derived from Chitinophaga sp. CB10, represents a significant advancement with broad implications. This enzyme displays exceptional stability and functionality under extreme conditions, operating effectively under both alkaline (pH 10.5) and thermophilic (80-90°C) environments. Its capability to maintain considerable activity over extended periods, even at high temperatures, showcases its potential for various industrial applications. Moreover, its distinctive ability to efficiently degrade lignin-demonstrated by a significant 52.27% degradation within 32 h-signifies a promising avenue for biorefinery processes. This newfound laccase's characteristics position it as a crucial asset in the realm of bioremediation, particularly in scenarios involving contamination at extreme pH and temperature levels. The study's findings highlight the enzyme's capacity to address challenges in industrial processes and environmental cleanup, signifying its vital role in advancing biotechnological solutions.

Reactive oxygen species impair Na+ transport and renal components of the renin-angiotensin-aldosterone system after paraquat poisoning.

Paraquat (1,1'-dimethyl-4,4'-bipyridyl dichloride) is an herbicide widely used worldwide and officially banned in Brazil in 2020. Kidney lesions frequently occur, leading to acute kidney injury (AKI) due to exacerbated reactive O2 species (ROS) production. However, the consequences of ROS exposure on ionic transport and the regulator local renin-angiotensin-aldosterone system (RAAS) still need to be elucidated at a molecular level. This study evaluated how ROS acutely influences Na+-transporting ATPases and the renal RAAS. Adult male Wistar rats received paraquat (20 mg/kg; ip). After 24 h, we observed body weight loss and elevation of urinary flow and serum creatinine. In the renal cortex, paraquat increased ROS levels, NADPH oxidase and (Na++K+)ATPase activities, angiotensin II-type 1 receptors, tumor necrosis factor-α (TNF-α), and interleukin-6. In the medulla, paraquat increased ROS levels and NADPH oxidase activity but inhibited (Na++K+)ATPase. Paraquat induced opposite effects on the ouabain-resistant Na+-ATPase in the cortex (decrease) and medulla (increase). These alterations, except for increased serum creatinine and renal levels of TNF-α and interleukin-6, were prevented by 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (tempol; 1 mmol/L in drinking water), a stable antioxidant. In summary, after paraquat poisoning, ROS production culminated with impaired medullary function, urinary fluid loss, and disruption of Na+-transporting ATPases and angiotensin II signaling.

Spectral changes in skin blood flow during pressure manipulations or sympathetic stimulation.

Skin blood flow is commonly determined by laser Doppler flowmetry (LDF). It has been suggested that pathophysiological conditions can be assessed by analysis of specific frequency domains of the LDF signals. We tested whether physiological stimuli that activate myogenic and neurogenic mechanisms would affect relevant portions of the laser Doppler spectrum. LDF sensors were placed on the right forearm of 14 healthy volunteers for myogenic (six females) and 13 for neurogenic challenge (five females). Myogenic responses were tested by positioning the arm ∼50° above/below heart level. Neurogenic responses were tested by immersing the left hand into an ice slurry with and without topical application of local anaesthetic. Short-time Fourier analyses were computed over the range of 0.06 to 0.15 Hz for myogenic and 0.02 to 0.06 Hz for neurogenic. No significant differences in spectral density were observed (P = 0.40) in the myogenic range with arm above (7 ± 54 × 10-4 dB) and below heart (7 ± 14 × 10-4 dB). Neurogenic spectral density showed no significant increase from baseline to cold pressor test (0.0017 ± 0.0013 and 0.0038 ± 0.0039 dB; P = 0.087, effect size 0.47). After application of anaesthetic, neurogenic spectral density was unchanged between the baseline and cold pressor test (0.0014 ± 0.0025 and 0.0006 ± 0.0005 dB; P = 0.173). These results suggest that changes in the myogenic and neurogenic spectral density of LDF signals did not fully reflect the skin vascular function activated by pressure manipulation and sympathetic stimulation. Therefore, LDF myogenic and neurogenic spectral density data should be interpreted with caution.

Forensic exploration of endodontic cements: Unveiling macroscopic and radiographic changes under high temperatures.

OBJECTIVE: To evaluate macroscopically and radiographically the behavior of four endodontic sealers submitted to high temperatures, with forensic purposes. METHODS: Sixty-four lower anterior teeth were included. All teeth were endodontically treated, and simulation of external cervical resorption (ECR) was performed. Half of the sample was filled with AH-Plus™ cement and had ECR sealed with Bio-C-Repair™. The other 32 teeth were filled with Bio-C-Sealer™ cement and had their respective ECR sealed with MTA-Repair™. Then, all teeth were introduced into a bovine bone block to simulate the alveolar bone. The teeth were submitted to incineration at temperatures of 600, 800, 1000, and 1140 °C. All teeth were radiographed before and after incineration. The pre-and post-incineration radiopacity of cements and dentin were evaluated using the ImageJ™ software and compared using a t-test for paired samples. RESULTS: It was possible to confirm color change and appearance of cracks in the tissues and dental materials tested, varying according to the temperature. Radiographically, it was observed that the dental crowns completely detached at 1000 ° and 1140 °C, and, only at 1140 °C, the roots showed cracks. Regarding the radiopacity, there was a significant difference in the shades of gray in AH-Plus™ when subjected to 1000 ° and 1140 °C, and at 600 ° and 1000 °C in Bio-C-Sealer™. In Bio-C-Repair™ and MTA-Repair™, a difference was observed at 600 ° and 1140 °C. CONCLUSIONS: There were macroscopic and radiographic alterations of the materials. This data is important in Forensic Dentistry and may contribute to identifying carbonized victims.

p63 controls metabolic activation of hepatic stellate cells and fibrosis via an HER2-ACC1 pathway.

The p63 protein has pleiotropic functions and, in the liver, participates in the progression of nonalcoholic fatty liver disease (NAFLD). However, its functions in hepatic stellate cells (HSCs) have not yet been explored. TAp63 is induced in HSCs from animal models and patients with liver fibrosis and its levels positively correlate with NAFLD activity score and fibrosis stage. In mice, genetic depletion of TAp63 in HSCs reduces the diet-induced liver fibrosis. In vitro silencing of p63 blunts TGF-ß1-induced HSCs activation by reducing mitochondrial respiration and glycolysis, as well as decreasing acetyl CoA carboxylase 1 (ACC1). Ectopic expression of TAp63 induces the activation of HSCs and increases the expression and activity of ACC1 by promoting the transcriptional activity of HER2. Genetic inhibition of both HER2 and ACC1 blunt TAp63-induced activation of HSCs. Thus, TAp63 induces HSC activation by stimulating the HER2-ACC1 axis and participates in the development of liver fibrosis.

The politicizing clinic: insights on 'the social' for mental health policy and practice.

PURPOSE: In this paper, we explore how Brazilian socially sensitive therapy can respond to care-users' desire to change the social and political forces shaping their lives. We use this case to demonstrate the limits of the "social determinants of health" agenda which, when operationalized, tends to leave questions of lasting structural change aside. METHODS: We report on mixed methods ethnographic and epidemiological results from the 1982 Pelotas (Brazil) birth cohort study, a prospective study of 5914 children. Ethnographic analysis explored the cyclical relationship between schooling, mental health care, conceptualizations of mental distress, social and political engagement, and experiences with diverse forms of discrimination. Epidemiological bivariate and multivariate analyses examined differences in socio-political participation and the reporting of discrimination at different time-points for participants who used therapy with those who did not. Effect modification analysis tested the hypothesis that the socially empowering effects of therapy were greater for marginalized and minoritized youth. RESULTS: Most young people living in situations of precarity experienced therapy, particularly when based in schools, to be a blame-inducing process. A more fulfilling and impactful therapeutic experience took shape when young people were able to shift the focus away from symptom reduction and behavioral management toward narrative life analyses, social debate, and political agency. Use of socially sensitive therapy was statistically associated with increased political participation and reporting of discrimination after controlling for confounders. The empowering effects of therapy were greater for those with less formal education and family income, but not for young people who identified as black, brown, or non-white. CONCLUSION: The findings underscore the importance of considering agency, sociality, and politics when theorizing "the social" in clinical practice, and health and social policy.

Reduction in peripheral arterial stiffness after reactive hyperemia is dependent on increases in blood flow.

The acute reduction in peripheral arterial stiffness during reactive hyperemia is assumed to be flow-mediated; however, the mechanism remains unproven. We hypothesized that restricting the blood flow increase during reactive hyperemia would abolish the reduction in peripheral arterial stiffness. Fourteen healthy young adults (5 females, 25 ± 5 years, mean ± SD) underwent reactive hyperemia with a rapid-release cuff on the upper arm inflated to 220 mmHg for 5 min: once with unrestricted blood flow and once with restricted blood flow by manually applying pressure to the brachial artery. Brachial-radial pulse wave velocity (PWV) was measured with tonometers over brachial and radial arteries before cuff inflation and at 5, 15, and 30 min after release. Brachial blood flow was monitored with Doppler ultrasound. Baseline brachial-radial PWV was similar between conditions (10.3 ± 1.8 vs. 10.7 ± 1.7 m/s). With unrestricted flow, PWV decreased 5 min post-reactive hyperemia (8.6 ± 1.1 m/s; p < 0.05) and returned near baseline at 15 and 30 min post (p < 0.05). With restricted flow, PWV did not change (p > 0.05) post-reactive hyperemia. Reactive hyperemia acutely reduced peripheral arterial stiffness, but not when brachial artery blood flow increase was restricted. This suggests that the reduction in peripheral arterial stiffness during reactive hyperemia depends on increased blood flow.

Zoonotic Giardia duodenalis assemblage A in northern sloth from Brazilian Amazon.

BACKGROUND: The parasite Giardia duodenalis infects a wide range of vertebrate hosts, including domestic and wild animals as well as humans. Giardia is genotyped into eight assemblages (A-H). Zoonotic assemblages A and B have already been identified in humans and wild and domestic animals (non-human primates and cats) from Brazilian Amazon and in the world. Due to its zoonotic/zooanthroponotic nature, surveillance initiatives and the definition of Giardia assemblages are important in order to characterise the epidemiological scenario and to implement further control measures. OBJECTIVES: Determine assemblages of G. duodenalis in sloths from the Brazilian Amazon Region. METHODS: Faecal parasitological examination of sloths from Amazonas State. Polymerase chain reaction (PCR) targeting the beta giardin (BG), and genes from multilocus sequence typing (MLST) scheme, amplicon sequencing and phylogenetic analysis. FINDINGS: Here, we identified, by microscopy, Giardia in two northern sloths (Bradypus tridactylus). These two samples were submitted to molecular assays and it was revealed that both were infected by G. duodenalis assemblage A. Phylogenetic analysis showed that they belong to assemblage A within sequences from humans and wild and domestic animals. CONCLUSION: Therefore, besides showing, by the first time, the current presence of this parasite in sloths, our findings reveals that this wild animal species would be part of the zoonotic/zooanthroponotic scenario of this parasite in the Brazilian Amazon.

Low Back Pain in Medical Students and Professors During the Pandemic: Retrospective Cohort Study.

Objective This study aimed to determine the prevalence of low back pain before and during the pandemic, comparing both periods. Methods A questionnaire was administered, containing questions about the presence of low back pain, sociodemographic characteristics and environmental factors that could be related to such pain. Results Among the 978 responses obtained, the prevalence of low back pain during the pandemic was 69.94%, which represented a significant increase over values from the pre-pandemic period (57.37%). A high prevalence of low back pain was found between all groups, especially among women. Some factors were associated with the incidence of low back pain, such as having previously diagnosed spinal problems and sedentary lifestyle. Conclusions The prevalence of low back pain increased significantly during the pandemic in the studied groups.

Neddylation of phosphoenolpyruvate carboxykinase 1 controls glucose metabolism.

Neddylation is a post-translational mechanism that adds a ubiquitin-like protein, namely neural precursor cell expressed developmentally downregulated protein 8 (NEDD8). Here, we show that neddylation in mouse liver is modulated by nutrient availability. Inhibition of neddylation in mouse liver reduces gluconeogenic capacity and the hyperglycemic actions of counter-regulatory hormones. Furthermore, people with type 2 diabetes display elevated hepatic neddylation levels. Mechanistically, fasting or caloric restriction of mice leads to neddylation of phosphoenolpyruvate carboxykinase 1 (PCK1) at three lysine residues-K278, K342, and K387. We find that mutating the three PCK1 lysines that are neddylated reduces their gluconeogenic activity rate. Molecular dynamics simulations show that neddylation of PCK1 could re-position two loops surrounding the catalytic center into an open configuration, rendering the catalytic center more accessible. Our study reveals that neddylation of PCK1 provides a finely tuned mechanism of controlling glucose metabolism by linking whole nutrient availability to metabolic homeostasis.

Low Back Pain in Medical Students and Professors During the Pandemic: Retrospective Cohort Study / Lombalgia em estudantes e professores de medicina durante a pandemia: Estudo de coorte retrospectivo

Abstract Objective This study aimed to determine the prevalence of low back pain before and during the pandemic, comparing both periods. Methods A questionnaire was administered, containing questions about the presence of low back pain, sociodemographic characteristics and environmental factors that could be related to such pain. Results Among the 978 responses obtained, the prevalence of low back pain during the pandemic was 69.94%, which represented a significant increase over values from the pre-pandemic period (57.37%). A high prevalence of low back pain was found between all groups, especially among women. Some factors were associated with the incidence of low back pain, such as having previously diagnosed spinal problems and sedentary lifestyle. Conclusions The prevalence of low back pain increased significantly during the pandemic in the studied groups.

Resumo Objetivo Este estudo teve como objetivo determinar a prevalência de lombalgia antes e durante a pandemia, comparando os dois períodos. Métodos Foi aplicado um questionário contendo questões sobre a presença de lombalgia, características sociodemográficas e hábitos que poderiam estar relacionados à essa dor. Resultados Entre as 978 respostas obtidas, a prevalência de lombalgia durante a pandemia foi de 69,94%, o que representou um aumento significativo em relação aos valores do período pré-pandêmico (57,37%). Foi encontrada alta prevalência de lombalgia entre todos os grupos, principalmente entre as mulheres. Alguns fatores foram associados à incidência de lombalgia, como ter problemas de coluna previamente diagnosticados e sedentarismo. Conclusões A prevalência de lombalgia aumentou significativamente durante a pandemia nos grupos estudados.

Prospective Association of Occupational and Leisure-Time Physical Activity With Cardiovascular Risk Factors in Early Adulthood: Findings From Pelotas (Brazil) 1982 Birth Cohort.

BACKGROUND: The benefits of physical activity in health outcomes are well established. However, recent evidence suggests that benefits may differ by domain and population. Thus, we aimed to investigate the prospective association of occupational (OPA) and leisure-time physical activity (LTPA) with cardiovascular risk factors. METHODS: In 1982, the maternity hospitals of Pelotas were visited daily; those live births whose families lived in urban areas were evaluated, and their mothers were later interviewed (n = 5914). In the 2004/5 follow-up (23 y old), both OPA and LTPA were measured in 4295 participants using their respective sections of the International Physical Activity Questionnaire. In the 2012 follow-up (30 y old), the following cardiovascular risk factors were collected: high-density lipoprotein (in milligrams per deciliter), low-density lipoprotein (in milligrams per deciliter), triglycerides (in milligrams per deciliter), glucose (in milligrams per deciliter), and blood pressure (in millimeters of mercury). Multivariable linear regressions were performed to evaluate associations between OPA and LTPA with these specific cardiovascular risk factors. RESULTS: In total, 3241 participants were analyzed. Our main findings suggest that there was no association between OPA and LTPA with high- and low-density lipoprotein. There were inverse associations between OPA and lower levels of triglycerides among males (ß = -0.002; 95% confidence interval, -0.003 to -0.000) and positive associations between LTPA and higher levels of diastolic blood pressure among females (ß = 0.111; 95% confidence interval, 0.005-0.216). CONCLUSION: In conclusion, our findings suggest that there was no association, or association with limited clinical relevance, of OPA and LTPA with cardiovascular risk factors in early adulthood.

Performance of Body Fat Percentage, Fat Mass Index and Body Mass Index for Detecting Cardiometabolic Outcomes in Brazilian Adults.

Obesity is a recognized risk factor for the development of cardiometabolic outcomes. Therefore, it is essential to evaluate anthropometric and body composition indicators used for its diagnosis. This study aimed to assess the diagnostic performance of body fat percentage (BF%), fat mass index (FMI) and body mass index (BMI) for detecting cardiometabolic outcomes in adults. A cross-sectional study was conducted involving adults at 30 years of age from Pelotas, RS (n = 3517) and at 37-39 years from Ribeirão Preto, SP (n = 1696). Receiver operating characteristic (ROC) curves were used to determine the cut-off points for predicting cardiometabolic risk factors, including altered blood pressure, blood glucose, triglycerides, total cholesterol, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDDL-c), C-reactive protein and glycated hemoglobin. The cut-off points of BF% ranged from 25.2 to 27.8 in men and from 37.4 to 39.7 in women at 30 years, and from 26.1 to 27.8 in men and from 38.5 to 42.2 in women at 37-39 years. For FMI (kg/m2), the cut-off points ranged from 6.3 to 7.5 in men and from 9.5 to 10.8 in women at 30 years, and from 7.3 to 7.8 in men and from 10.2 to 12.2 in women at 37-39 years. The BMI cut-off points (kg/m2) ranged from 26.3 to 27.3 in men and from 25.4 to 27.2 in women at 30 years, and from 28.3 to 29.0 in men and from 27.2 to 29.6 in women at 37-39 years. The areas under the curve were similar for the three indicators, ranging from 0.523 to 0.746. BMI showed a performance similar to that of the body fat-based indicators in identifying cardiometabolic outcomes. The cut-off points of the three indicators showed acceptable discriminatory power in subjects with cardiometabolic risk factors.

Hepatocyte-specific O-GlcNAc transferase downregulation ameliorates nonalcoholic steatohepatitis by improving mitochondrial function.

OBJECTIVE: O-GlcNAcylation is a post-translational modification that directly couples the processes of nutrient sensing, metabolism, and signal transduction, affecting protein function and localization, since the O-linked N-acetylglucosamine moiety comes directly from the metabolism of glucose, lipids, and amino acids. The addition and removal of O-GlcNAc of target proteins are mediated by two highly conserved enzymes: O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) and O-GlcNAcase (OGA), respectively. Deregulation of O-GlcNAcylation has been reported to be associated with various human diseases such as cancer, diabetes, and cardiovascular diseases. The contribution of deregulated O-GlcNAcylation to the progression and pathogenesis of NAFLD remains intriguing, and a better understanding of its roles in this pathophysiological context is required to uncover novel avenues for therapeutic intervention. By using a translational approach, our aim is to describe the role of OGT and O-GlcNAcylation in the pathogenesis of NAFLD. METHODS: We used primary mouse hepatocytes, human hepatic cell lines and in vivo mouse models of steatohepatitis to manipulate O-GlcNAc transferase (OGT). We also studied OGT and O-GlcNAcylation in liver samples from different cohorts of people with NAFLD. RESULTS: O-GlcNAcylation was upregulated in the liver of people and animal models with steatohepatitis. Downregulation of OGT in NAFLD-hepatocytes improved diet-induced liver injury in both in vivo and in vitro models. Proteomics studies revealed that mitochondrial proteins were hyper-O-GlcNAcylated in the liver of mice with steatohepatitis. Inhibition of OGT is able to restore mitochondrial oxidation and decrease hepatic lipid content in in vitro and in vivo models of NAFLD. CONCLUSIONS: These results demonstrate that deregulated hyper-O-GlcNAcylation favors NAFLD progression by reducing mitochondrial oxidation and promoting hepatic lipid accumulation.

Birth conditions nutritional status in childhood associated with cardiometabolic risk factors at 30 years of age: a cohort study.

This study aimed to assess the association of birth conditions, nutritional status, and childhood growth with cardiometabolic risk factors at 30 years of age. We also evaluated whether body mass index (BMI) at 30 years mediated the association of weight gain in childhood with cardiometabolic risk factors. This is a prospective cohort study that included all live births in 1982 in hospitals in the city of Pelotas, Rio Grande do Sul State, Brazil, whose families lived in the urban area. Mothers were interviewed at birth, and participants were followed at different ages. For our analyses, we used data on weight and height collected at birth, 2 and 4 years and cardiovascular risk factors at 30 years. Multiple linear regressions were performed to obtain adjusted coefficients and G-formula for mediation analysis. Relative weight gain in childhood, despite the age, was positively related to mean arterial pressure, whereas relative weight gain in late childhood was positively associated with carotid intima-media thickness, pulse wave velocity, triglycerides, non-HDL cholesterol, plasma glucose, and C-reactive protein. BMI in adulthood captured the total effect of relative weight gain in the period between 2 and 4 years on carotid intima-media thickness, triglycerides, non-HDL cholesterol, and C-reactive protein. Our findings reinforce the evidence that rapid relative weight gain after 2 years of age may have long-term consequences on the risk of metabolic and cardiovascular disorders.

Growth patterns in childhood and adolescence and adult body composition: a pooled analysis of birth cohort studies from five low and middle-income countries (COHORTS collaboration).

OBJECTIVE: We examined associations among serial measures of linear growth and relative weight with adult body composition. DESIGN: Secondary data analysis of prospective birth cohort studies. SETTINGS: Six birth cohorts from Brazil, Guatemala, India, the Philippines and South Africa. PARTICIPANTS: 4173 individuals followed from birth to ages 22-46 years with complete and valid weight and height at birth, infancy, childhood and adolescence, and body composition in adult life. EXPOSURES: Birth weight and conditional size (standardised residuals of height representing linear growth and of relative weight representing weight increments independent of linear size) in infancy, childhood and adolescence. PRIMARY OUTCOME MEASURES: Body mass index, fat mass index (FMI), fat-free mass index (FFMI), fat mass/fat-free mass ratio (FM/FFM), and waist circumference in young and mid-adulthood. RESULTS: In pooled analyses, a higher birth weight and relative weight gains in infancy, childhood and adolescence were positively associated with all adult outcomes. Relative weight gains in childhood and adolescence were the strongest predictors of adult body composition (ß (95% CI) among men: FMI (childhood: 0.41 (0.26 to 0.55); adolescence: 0.39 (0.27 to 0.50)), FFMI (childhood: 0.50 (0.34 to 0.66); adolescence: 0.43 (0.32 to 0.55)), FM/FFM (childhood: 0.31 (0.16 to 0.47); adolescence: 0.31 (0.19 to 0.43))). Among women, similar patterns were observed, but, effect sizes in adolescence were slightly stronger than in childhood. Conditional height in infancy was positively associated with FMI (men: 0.08 (0.03 to 0.14); women: 0.11 (0.07 to 0.16)). Conditional height in childhood was positively but weakly associated with women's adiposity. Site-specific and sex-stratified analyses showed consistency in the direction of estimates, although there were differences in their magnitude. CONCLUSIONS: Prenatal and postnatal relative weight gains were positive predictors of larger body size and increased adiposity in adulthood. A faster linear growth in infancy was a significant but weak predictor of higher adult adiposity.

Dynamics of the role of LacMeta laccase in the complete degradation and detoxification of malachite green.

Laccases highlight for xenobiotic bioremediation, as well as application in the fine chemical, textile, biofuel and food industries. In a previous work, we described the preliminary characterization of laccase LacMeta, a promising enzyme for the bioremediation of dyes, able to decolorization malachite green (MG), trypan blue, methylene blue. Here we demonstrate that LacMeta is indeed suitable for the complete degradation and detoxification of MG dye, not just for its discoloration, since some works show false positives due to the formation of colorless intermediates such as leucomalachite. The optimal pH and temperature parameters of LacMeta were 5.0 and 50 °C, respectively (MG as substrate). LacMeta was tolerant of up to 10 mmol L- 1 EDTA (82%) and up to 5% (V/V) acetone (91%) and methanol (71%), while SDS promoted severe inhibition. For ions, a high tolerance to cobalt, zinc, manganese, and calcium (10 mmol L- 1) was also observed (> 90%). Even under high-salinity conditions (1 mol L- 1 NaCl), the residual bleaching activity of the dye remained at 61%. Furthermore, the bleaching product of MG did not inhibit the germination of sorghum and tomato seeds and was inert to the vegetative structures of the germinated seedlings. Additionally, this treatment effectively reduced the cytotoxic effect of the dye on microorganisms (Escherichia coli and Azospirillum brasilense), which can be explained by H-NMR spectral analysis results since LacMeta completely degraded the peak signals corresponding to the aromatic rings in the dye, demonstrating extreme efficiency in the bioremediation of the xenobiotic at high concentrations (50 mg L- 1).

Maternal smoking during pregnancy and birthweight on the third generation: results from two birth cohort studies.

The purpose of this research is to investigate whether grandmother's smoking during pregnancy reduces the grandchildren's birthweight and whether maternal smoking during pregnancy modified this association. We also evaluated the effect of duration and intensity of smoking. This study included data from three generations from two birth cohorts carried out in Pelotas, a southern Brazilian city: women enrolled in the perinatal study in the 1982 and 1993 cohorts (G1); daughters (G2) of those G1 mothers who were followed to adulthood; and first children (G3) born from G2 women. Information on maternal smoking during pregnancy was obtained from women (G1) shortly after delivery of the two cohorts and from G2 in the follow-up in adulthood of the 1993 cohort. Mothers (G2) reported G3 birthweight during the follow-up visit at adulthood. Multiple linear regression was used to obtain effect measures adjusted for confounders. The study included 1602 grandmothers (G1), mothers (G2), and grandchildren (G3). Prevalence of maternal (G1) smoking during pregnancy was 43% and mean G3 birthweight was 3118.9 g (SD: 608.8). Grandmother's smoking in the pregnancy was not associated with grandchild's birthweight. However, offspring of both G1 and G2 smokers had lower mean birthweight than those whose mother and grandmother did not smoke (adjusted ß: - 223.05; 95% CI: - 415.16, - 32.76). CONCLUSION: No significant association was observed between grandmother's smoking in the pregnancy and grandchild's birthweight. But it seems that grandmother's smoking in pregnancy has an effect on grandchild's birthweight when the mother also smoked in the pregnancy. . WHAT IS KNOWN: • Most studies on the association of maternal tobacco smoking in pregnancy with offspring birthweight have been restricted to two generations, and an inverse association is well known. WHAT IS NEW: • Besides to investigate whether grandmother's smoking during pregnancy reduces the grandchildren's birthweight, we examined whether this association varied according to maternal smoking during pregnancy.

Hepatic p63 regulates glucose metabolism by repressing SIRT1.

OBJECTIVE: p63 is a transcription factor within the p53 protein family that has key roles in development, differentiation and prevention of senescence, but its metabolic actions remain largely unknown. Herein, we investigated the physiological role of p63 in glucose metabolism. DESIGN: We used cell lines and mouse models to genetically manipulate p63 in hepatocytes. We also measured p63 in the liver of patients with obesity with or without type 2 diabetes (T2D). RESULTS: We show that hepatic p63 expression is reduced on fasting. Mice lacking the specific isoform TAp63 in the liver (p63LKO) display higher postprandial and pyruvate-induced glucose excursions. These mice have elevated SIRT1 levels, while SIRT1 knockdown in p63LKO mice normalises glycaemia. Overexpression of TAp63 in wild-type mice reduces postprandial, pyruvate-induced blood glucose and SIRT1 levels. Studies carried out in hepatocyte cell lines show that TAp63 regulates SIRT1 promoter by repressing its transcriptional activation. TAp63 also mediates the inhibitory effect of insulin on hepatic glucose production, as silencing TAp63 impairs insulin sensitivity. Finally, protein levels of TAp63 are reduced in obese persons with T2D and are negatively correlated with fasting glucose and homeostasis model assessment index. CONCLUSIONS: These results demonstrate that p63 physiologically regulates glucose homeostasis.