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Adsorptive Features of Magnetic Activated Carbons Prepared by a One-Step Process towards Brilliant Blue Dye
Water pollution by dyes has been a major environmental problem to be tackled, and magnetic adsorbents appear as promising alternatives to solve it. Herein, magnetic activated carbons were prepared by the single−step method from Sapelli wood sawdust, properly characterized, and applied as adsorbents for brilliant blue dye removal. In particular, two magnetic activated carbons, MAC1105 and MAC111, were prepared using the proportion of biomass KOH of 1:1 and varying the proportion of NiCl2 of 0.5 and 1. The characterization results demonstrated that the different proportions of NiCl2 mainly influenced the textural characteristics of the adsorbents. An increase in the surface area from 260.0 to 331.5 m2 g−1 and in the total pore volume from 0.075 to 0.095 cm3 g−1 was observed with the weight ratio of NiCl2. Both adsorbents exhibit ferromagnetic properties and the presence of nanostructured Ni particles. The different properties of the materials influenced the adsorption kinetics and equilibrium of brilliant blue dye. MAC111 showed faster kinetics, reaching the equilibrium in around 10 min, while for MAC1105, it took 60 min for the equilibrium to be reached. In addition, based on the Sips isotherm, the maximum adsorption capacity was 98.12 mg g−1 for MAC111, while for MAC1105, it was 60.73 mg g−1. Furthermore, MAC111 presented the potential to be reused in more adsorption cycles than MAC1105, and the use of the adsorbents in the treatment of a simulated effluent exhibited high effectiveness, with removal efficiencies of up to 90%.
Journal Article
Thermodynamic Properties of γ- and δ-Lactones: Exploring Alkyl Chain Length Effect and Ring-Opening Reactions for Green Chemistry Applications
An extensive thermochemical study of γ-undecanolactone and δ-undecanolactone has been developed using two complementary calorimetric techniques. The combustion energy of each compound was determined by static-bomb combustion calorimetry, and the corresponding enthalpy of vaporization was determined by high-temperature Calvet microcalorimetry, in which both properties of each compound are reported at T = 298.15 K. The standard molar enthalpy of formation in the gas phase of each lactone was derived by the combination of the experimental results. Additionally, high-level computational calculations were carried out, using composite ab initio G4 and G4(MP2) methods, as well as DFT M06-2X/6-311++G(d,p) approach, to estimate the corresponding enthalpy of formation in the gas phase. The experimental and computational results are in good agreement. The G4 and G4(MP2) methods show the best accordance with experimentally determined gas phase enthalpies of formation. The experimental results are discussed in terms of structural contributions to the energetic properties of the lactones studied, as well as to other alkylated γ- and δ-lactones, and empirical correlations are suggested for the estimation of the standard molar enthalpies of formation, at T = 298.15 K, for other alkylated γ- and δ-lactones, both in the liquid and gaseous phases, as well as for the respective enthalpies of vaporization. Finally, the thermochemistry of individual steps of lactone ring opening and successive decarboxylation mechanism, including the identification of transition states, was studied using the M06-2X/6-311++G(d,p) approach.
Journal Article
Discrepancies at clinical presentation of patients with soft tissue sarcoma according to the type of health insurance in a Brazilian population
In Brazil, 75% of the population is covered by public health insurance (PubHIn), and the rest pay for private insurance (PrivHIn). The impact of the type of health insurance on clinical presentation of Brazilian patients diagnosed with soft tissue sarcoma (STS) is unknown. We aim to describe the clinical characteristics at diagnosis of patients with STS, stratifying them by type of health insurance, and to evaluate the symptom-diagnosis and -treatment intervals.
Observational, retrospective cohort, single-center study conducted in a Brazilian cancer center that admits both private and public patients. Medical records of individuals with 18 years old or more diagnosed with selected types of STS who started treatment in our center between January 2011 and December 2019 were reviewed. Kaplan-Meier method and log-rank test were used for survival analyses. Chi-square and Mann Whitney test were used for univariate analysis. Significance was defined as a p-value <0.05.
225 patients were included: 25.3% (n=57) with PubHIn and 74.7% (n=168) with PrivHIn. Median tumor size in PrivHIn was 7 cm (0.9-45 cm) versus 10.3 cm (0.8-30.5 cm) in PubHIn (p=0.0001). Metastases were present in 8.9% of patients with PrivHIn (n=15) and in 26.3% (n=15) of those with PubHIn (p=0.002). Median symptom-diagnosis interval was 195 days in the PubHIn group and 163 days in the PrivHIn group (p=0.74). For the whole series, median age at diagnosis was 51 years (18-85 yo). Lower limbs were the most frequent location of tumors (53.8%), and 86% had histological grade 2/3.
Patients with STS covered by PubHIn presented larger tumors and more metastatic disease at diagnosis, suggesting that there may be disparities in health care delivery and limited access to health resources. A better understanding of the barriers in the journey of patients with STS could improve outcomes.
Journal Article
Evidence of drought memory in Dipteryx alata indicates differential acclimation of plants to savanna conditions
The remarkable phytogeographic characteristics of the Brazilian savanna (Cerrado) resulted in a vegetation domain composed of plants with high structural and functional diversity to tolerate climate extremes. Here we used a key Cerrado species (
Dipteryx alata
) to evaluate if species of this domain present a mechanism of stress memory, responding more quickly and efficiently when exposed to recurrent drought episodes. The exposure of
D. alata
seedlings to drought resulted in several changes, mainly in physiological and biochemical traits, and these changes differed substantially when the water deficit was imposed as an isolated event or when the plants were subjected to drought cycles, suggesting the existence of a drought memory mechanism. Plants submitted to recurrent drought events were able to maintain essential processes for plant survival when compared to those submitted to drought for the first time. This differential acclimation to drought was the result of orchestrated changes in several metabolic pathways, involving differential carbon allocation for defense responses and the reprogramming and coordination of primary, secondary and antioxidant metabolism. The stress memory in
D. alata
is probably linked the evolutionary history of the species and reflects the environment in which it evolved.
Journal Article
Microbial community structure and dynamics in thermophilic composting viewed through metagenomics and metatranscriptomics
Composting is a promising source of new organisms and thermostable enzymes that may be helpful in environmental management and industrial processes. Here we present results of metagenomic- and metatranscriptomic-based analyses of a large composting operation in the São Paulo Zoo Park. This composting exhibits a sustained thermophilic profile (50 °C to 75 °C), which seems to preclude fungal activity. The main novelty of our study is the combination of time-series sampling with shotgun DNA, 16S rRNA gene amplicon, and metatranscriptome high-throughput sequencing, enabling an unprecedented detailed view of microbial community structure, dynamics, and function in this ecosystem. The time-series data showed that the turning procedure has a strong impact on the compost microbiota, restoring to a certain extent the population profile seen at the beginning of the process; and that lignocellulosic biomass deconstruction occurs synergistically and sequentially, with hemicellulose being degraded preferentially to cellulose and lignin. Moreover, our sequencing data allowed near-complete genome reconstruction of five bacterial species previously found in biomass-degrading environments and of a novel biodegrading bacterial species, likely a new genus in the order Bacillales. The data and analyses provided are a rich source for additional investigations of thermophilic composting microbiology.
Journal Article
The Impact of Health Literacy on Knowledge and Attitudes towards Preventive Strategies against COVID-19: A Cross-Sectional Study
The coronavirus disease 2019 (COVID-19) pandemic introduced a set of mitigation measures based on personal behavior and attitudes. In the absence of vaccination or specific treatment, it became essential to comply with these measures to reduce infection transmission. Health literacy is the basis for changing behaviors. AIM: To characterize the impact of literacy on knowledge and attitudes towards preventive strategies against COVID-19. METHODS: This cross-sectional study involved an online questionnaire applied to students of the University of Porto, Portugal, containing questions about knowledge and attitudes towards COVID-19 based on European guidelines. Health literacy was assessed through the Newest Vital Sign questionnaire. Logistic regression estimated the relationship between health literacy and both knowledge and attitudes. RESULTS: We included 871 participants (76.3% female), with a median age of 22 years old. We found adequate literacy in 92% of our sample, irrespective of gender and age. In the global analysis, 78.6% of the participants had adequate knowledge, and 90.4% had adequate attitudes. We found that better literacy was significantly associated with attitudes towards COVID-19, but not with better knowledge. In a model adjusted for gender, age, and previous education in the health field, female gender and previous education in the health field were associated with better knowledge and attitudes. CONCLUSION: Better health literacy is associated with better attitudes towards preventive strategies against COVID-19. We should invest in ways to improve health literacy, so we can improve people’s attitudes and consequently reduce coronavirus’ transmission.
Journal Article
SAMHD1 acts at stalled replication forks to prevent interferon induction
SAMHD1 was previously characterized as a dNTPase that protects cells from viral infections. Mutations in SAMHD1 are implicated in cancer development and in a severe congenital inflammatory disease known as Aicardi–Goutières syndrome. The mechanism by which SAMHD1 protects against cancer and chronic inflammation is unknown. Here we show that SAMHD1 promotes degradation of nascent DNA at stalled replication forks in human cell lines by stimulating the exonuclease activity of MRE11. This function activates the ATR–CHK1 checkpoint and allows the forks to restart replication. In SAMHD1-depleted cells, single-stranded DNA fragments are released from stalled forks and accumulate in the cytosol, where they activate the cGAS–STING pathway to induce expression of pro-inflammatory type I interferons. SAMHD1 is thus an important player in the replication stress response, which prevents chronic inflammation by limiting the release of single-stranded DNA from stalled replication forks.
SAMHD1 has an essential role in the replication stress response and prevents inflammation by activating the MRE11 nuclease to degrade nascent DNA strands at stalled replication forks, thus enabling replication.
Journal Article
Parental Involvement during Pandemic Times: Challenges and Opportunities
Due to COVID-19, many countries implemented emergency plans, such as lockdown and school closures. This new situation has significantly affected families, namely, the involvement required to support children’s learning at home. The current study aimed to analyze Portuguese parents’ perceptions of their home-based parental involvement in their children’s learning during the lockdown and school closures in 2020 due to COVID-19. An online survey, using a closed-ended questionnaire, was employed. Variables included parents’ sociodemographic and COVID-19 related characteristics; students’ sociodemographic characteristics; distance learning context; parental involvement; and students’ autonomy. Data were collected from a sample of 21,333 parents with children from elementary school to secondary education, and statistical data analysis was performed using IBM SPSS Statistics 26. Findings revealed that Portuguese parents supported their children during the pandemic mainly through the monitoring of attention in classes and task realization. However, several variables appear to significantly determine parental involvement time, which is higher when students attend public schools, when they are less autonomous and younger, when parents’ level of education is lower, when the child is a boy (except in secondary education where gender is not relevant), and when the online school time is higher. Findings highlight the need for a significant investment of time from parents, particularly of primary school children, making it difficult to cohere work or telework with school activities. Implications for policies, schools, families are discussed in order to promote children’s learning and success.
Journal Article
Development and Validation of Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) for Rapid Detection of ZIKV in Mosquito Samples from Brazil
The rapid spread of Zika virus (ZIKV) represents a global public health problem, especially in areas that harbor several mosquito species responsible for virus transmission, such as Brazil. In these areas, improvement in mosquito control needs to be a top priority, but mosquito viral surveillance occurs inefficiently in ZIKV-endemic countries. Quantitative reverse transcription PCR (qRT-PCR) is the gold standard for molecular diagnostic of ZIKV in both human and mosquito samples. However, the technique presents high cost and limitations for Point-of-care (POC) diagnostics, which hampers its application for a large number of samples in entomological surveillance programs. Here, we developed and validated a one-step reverse transcription LAMP (RT-LAMP) platform for detection of ZIKV in mosquito samples. The RT-LAMP assay was highly specific for ZIKV and up to 10,000 times more sensitive than qRT-PCR. Assay validation was performed using 60 samples from
Aedes aegypti
and
Culex quinquefasciatus
mosquitoes collected in Pernambuco State, Brazil, which is at the epicenter of the Zika epidemic. The RT-LAMP had a sensitivity of 100%, specificity of 91.18%, and overall accuracy of 95.24%. Thus, our POC diagnostics is a powerful and inexpensive tool to monitor ZIKV in mosquito populations and will allow developing countries to establish better control strategies for this devastating pathogen.
Journal Article