Particulate matter pollution and non-targeted analysis of polar compounds in three regions of Brazil.

Atmospheric Particulate Matter (PM) is a pollutant with diverse origins, exhibiting varying chemical compositions, and undergoes several molecular transformations in the atmosphere. In this study, PM samples (PM2.5, PM10 and TSP) were collected in five Brazilian cities (Camboriú-SC; Catalão-GO; Florianópolis-SC; Limeira-SP and Novo Hamburgo-RS) during the four seasons of the year. Analysis of Variance (ANOVA) was used to evaluate the differences between each city and season in PM concentration. PM10 average concentrations were higher in the city of Limeira, compared to the other (ANOVA p-values and Tukey's test). Moreover, Tukey's test demonstrated differences between the average PM10 concentrations in summer and winter. Regarding TSP and PM2.5, Tukey's test showed differences between winter and warm seasons (spring and summer). Moreover, polar compounds from the samples collected in the summer (February) and winter (August) periods were analyzed (Ultra-High-Performance Liquid Chromatography coupled to a Quadrupole Time-of-Flight Mass Spectrometer) following a non-targeted approach and annotated. This is the first study to carry out this type of analysis in these five Brazilian cities. Despite the differences in PM concentrations, profiles of polar organic compounds, showed similarities between samples/and, in general, the same compounds were present, albeit with different intensities. The annotated compounds are associated with vehicle emissions and plastics, which are considered important global air polluters. Therefore, there is an urgent necessity for comprehensive studies aimed at investigating the non-targeted compounds existing in the atmosphere. Such research can provide invaluable insights to policymakers, enabling them to formulate effective guidelines and policies to mitigate particulate matter concentration and enhance overall air quality.

Reducing the pollution load of tannery wastewater and the atmospheric emission of hydrogen sulfide using modified tannin.

Industrial wastewater causes several environmental and health issues due to its composition, and hydrogen sulfide is one of the main contaminants from various industrial activities, including tannery wastewater treatment plants. This study aimed to evaluate the application of a modified tannin to remove hydrogen sulfide, chemical oxygen demand, total nitrogen, color, and turbidity from tannery wastewater and to reduce the atmospheric emission of sulfides. The wastewater was treated using modified tannin, aluminum sulfate, and a combination of both. Gaseous sulfide emissions were analyzed qualitatively using paper soaked in lead acetate. The qualitative methodology of hydrogen sulfide in the atmosphere was efficient to identify the most critical areas in the tannery. The wastewater treatment tests showed that the best option was the combination of both coagulants, in a 50:50 ratio, resulting in a total coagulant dosage of 3,000 mg/L. The removal efficiencies achieved were 13.8% sulfides, 23.3% chemical oxygen demand, 9.1% total nitrogen, 97.3% turbidity, and 96.4% color. This treatment technique promotes the replacement of 50% of the aluminum sulfate currently used in the tannery by a non-toxic coagulant and does not require chemicals to adjust the pH of the wastewater.

Susceptibility to endemic Aedes-borne viruses among pregnant women in Risaralda, Colombia.

OBJECTIVES: Aedes-borne viruses (ABV) affect humans on every inhabited continent and frequently cause epidemics. Recent epidemics of chikungunya and Zika viruses (ZIKV) highlight that preparedness for future epidemics requires assessment of susceptibility, particularly among high-risk groups. We sought to determine immunity against the three major circulating ABV among pregnant women in an ABV-endemic area of Colombia. METHODS: A cross-sectional seroprevalence study was performed, enrolling women presenting to Labor and Delivery. Cord blood and maternal peripheral blood samples were obtained. IgG seroprevalence to flaviviruses and chikungunya was determined by ELISA. An abbreviated neutralization test was used to estimate the frequency and magnitude of immunity to Zika and four dengue serotypes. Cluster analyses explored epidemiologic factors associated with seroprevalence. RESULTS: Most women exhibited high levels of neutralizing antibodies to one or more ABV; however, nearly 20% were seronegative for flaviviruses. Our research took place after the epidemic peak of the ZIKV outbreak in Colombia in 2016. However, only 20% of pregnant women had high levels of Zika-neutralizing antibodies consistent with likely protective immunity to ZIKV. CONCLUSION: Hence, a high proportion of pregnant women in Risaralda remain susceptible to one or more ABV including the teratogenic ZIKV, indicating a risk for future epidemics in this region.

Source apportionment of metallic elements in urban atmospheric particulate matter and assessment of its water-soluble fraction toxicity.

Clean air is essential for the maintenance of human life and environmental balance. The atmospheric particulate matter (PM) is one of the main air pollutants and is characterized by the heterogeneity of its composition, being able to accumulate numerous components, such as metallic elements, which contribute to increasing its toxicity. The objectives of this study were to assess of the air quality in two urban environments, to carry out the source apportionment of the metallic elements Al, Ba, Cd, Pb, Cu, Cr, Fe, Mn, Ni, and Zn in the PM2.5 and PM2.5-10, and evaluate the toxicity of PM2.5 and PM2.5-10 water-soluble fractions using Lactuca sativa as bioindicator. The collection of PM2.5 and PM2.5-10 was performed using a dichotomous stacked filter unit (SFU) sampler. The source apportionment was carried out using the EPA PMF 5.0 receptor model and the toxicity tests followed the EPA Ecological Effects Test Guidelines OPPTS 850.4200: Seed Germination/Root Elongation Toxicity Test. The source apportionment demonstrated that vehicular and industrial emissions are the main anthropogenic sources contributing to the concentration of metallic elements to thePM2.5 and PM2.5-10. The studied sites did not show statistically significant differences in terms of phytotoxicity to the Lactuca sativa seeds. Cd and Cu were identified as the main metallic elements which able to cause negative effects on seed germination and root elongation, respectively. The presence of cadmium and copper in the atmospheric particulate matter is one of the main causes of the phytotoxicity affecting the Lactuca sativa seed germination and root elongation.

La estimulación táctil/kinestésica revierte los efectos del estrés prenatal en la región CA3 del hipocampo en ratas hembras: estudio estereológico / Tactile/kinesthetic stimulation reverses the effects of prenatal stress in the CA3 region of the hippocampus in female rats: a stereological study

Esta investigación fue realizada para saber si la estimulación táctil/kinestésica postnatal es efectiva en revertir el estrés prenatal, en la citoarquitectura de CA3 del hipocampo, en crías hembras. 12 crías de ratas hembras de la cepa Sprague-Dawley, fueron distribuidas en Grupo Control (GC), Grupo con Estrés Prenatal por restricción (EP) y Grupo Estrés prenatal con Estimulación Táctil/Kinestésica postnatal (EP-ETK). El estrés prenatal en crías hembras aumentó la densidad neuronal en las áreas CA3b y CA3c (p<0,001). Cuando se compararon las crías con estrés prenatal con las que recibieron estimulación táctil/kinestésica temprana, disminuyeron las densidades neuronales en las áreas CA3b y CA3c, (p < 0,001). La estimulación táctil/kinestésica postnatal logró revertir los efectos del estrés prenatal, al reducir la densidad neuronal en las áreas CA3b y CA3c del hipocampo.

This investigation was undertaken in order to know whether the postnatal tactile/kinesthetic stimulation is effective in reversing the Prenatal Stress, in the cytoarchitecture of the CA3 region of the hippocampus, in female pups. 12 pups of female rats from the Sprague-Dawley strain were distributed to Control Group (GC), the Prenatal Maternal Stress by restriction group (EP) and Prenatal Maternal Stress with postnatal tactile/ kinesthetic stimulation Group (EP-ETK). The Prenatal Maternal Stress in female pups increased neuronal density in CA3b and CA3c areas (p<0.001). When compared to Prenatal Maternal Stress, pups prenatal stress who received early tactile/kinesthetic stimulation showed a decrease in neuronal density in CA3b and CA3c areas (p < 0,001). Postnatal tactile/kinesthetic stimulation was shown to successfully reverse the Prenatal Maternal Stress effects by decreasing neuronal density in CA3b and CA3c hippocampal areas.

Chemical composition of rainwater in the Sinos River Basin, Southern Brazil: a source apportionment study.

This study aimed to assess the chemical composition of the rainwater in three areas of different environmental impact gradients in Southern Brazil using the receptor model EPA Positive Matrix Factorization (EPA PMF 5.0). The samples were collected in a bulk sampler, from October 2012 to August 2014, in three sampling sites along with the Sinos River Basin: Caraá, Taquara, and Campo Bom. The major ions NH4+, Na+, K+, Ca2+, Mg2+, F-, Cl-, NO3-, SO42-, and pH were analyzed, as well as identify the main emission sources. The most abundant cations and anions were Ca2+, Na+, Cl-, and SO42-, respectively. The mean pH value in the Sinos River Basin during the study period was 6.07 ± 0.49 (5.13-7.05), which suggests inputs of alkaline species into the atmosphere. The most important neutralizing agents of sulfuric and nitric acids in the Sinos River Basin are Ca2+ (NF = 1.36) and NH4+ (NF = 0.57). The source apportionment provided by the EPA PMF 5.0 resulted in four factors, which demonstrate the influence of anthropogenic and natural sources, in the form of (a) industry/combustion of fossil fuels (F- and SO42-), (b) marine contribution (Na+ and Cl-), (c) crustal contribution (K+, Ca2+, and NO3-), and (d) agriculture/livestock (NH4+). Therefore, this study allows a more appropriate understanding of factors that contribute to rainwater chemical composition and also to possible changes in air quality.

Seasonal assessment and apportionment of surface water pollution using multivariate statistical methods: Sinos River, southern Brazil.

Assessment of surface water quality is an issue of currently high importance, especially in polluted rivers which provide water for treatment and distribution as drinking water, as is the case of the Sinos River, southern Brazil. Multivariate statistical techniques allow a better understanding of the seasonal variations in water quality, as well as the source identification and source apportionment of water pollution. In this study, the multivariate statistical techniques of cluster analysis (CA), principal component analysis (PCA), and positive matrix factorization (PMF) were used, along with the Kruskal-Wallis test and Spearman's correlation analysis in order to interpret a water quality data set resulting from a monitoring program conducted over a period of almost two years (May 2013 to April 2015). The water samples were collected from the raw water inlet of the municipal water treatment plant (WTP) operated by the Water and Sewage Services of Novo Hamburgo (COMUSA). CA allowed the data to be grouped into three periods (autumn and summer (AUT-SUM); winter (WIN); spring (SPR)). Through the PCA, it was possible to identify that the most important parameters in contribution to water quality variations are total coliforms (TCOLI) in SUM-AUT, water level (WL), water temperature (WT), and electrical conductivity (EC) in WIN and color (COLOR) and turbidity (TURB) in SPR. PMF was applied to the complete data set and enabled the source apportionment water pollution through three factors, which are related to anthropogenic sources, such as the discharge of domestic sewage (mostly represented by Escherichia coli (ECOLI)), industrial wastewaters, and agriculture runoff. The results provided by this study demonstrate the contribution provided by the use of integrated statistical techniques in the interpretation and understanding of large data sets of water quality, showing also that this approach can be used as an efficient methodology to optimize indicators for water quality assessment.

Integrated assessment of air pollution by metals and source apportionment using ryegrass (Lolium multiflorum Lam.) in southern Brazil.

One of the biggest environmental problems existing today is air pollution, which is characterized by the presence of toxic gases and metal pollutants, the latter of which is generally associated with emissions of particulate matter (PM) from industries or automotive vehicles. Biomonitoring is a method that can be used to assess air pollution levels because it makes it possible to determine what effects these air pollutants cause in living organisms and their responses. The species Lolium multiflorum Lam., known as ryegrass, is considered a good bioindicator of metals, since it accumulates these substances during exposure. This study proposes to conduct an integrated assessment of air quality using two different monitoring methodologies: biomonitoring with L. multiflorum and active monitoring in areas with different levels of urbanization and industrialization. Concentrations found in ryegrass plants revealed high levels of Pb, Cr, Zn, and Cu, indicating that vehicular and industrial emissions were the main sources of pollution. Analysis of PM also revealed soot and biogenic particles, which can transport metals. Therefore, with the proposed method, the anthropogenic impact on air pollution in the investigated area could be clearly demonstrated.

Genomic survey of pathogenicity determinants and VNTR markers in the cassava bacterial pathogen Xanthomonas axonopodis pv. Manihotis strain CIO151.

Xanthomonas axonopodis pv. manihotis (Xam) is the causal agent of bacterial blight of cassava, which is among the main components of human diet in Africa and South America. Current information about the molecular pathogenicity factors involved in the infection process of this organism is limited. Previous studies in other bacteria in this genus suggest that advanced draft genome sequences are valuable resources for molecular studies on their interaction with plants and could provide valuable tools for diagnostics and detection. Here we have generated the first manually annotated high-quality draft genome sequence of Xam strain CIO151. Its genomic structure is similar to that of other xanthomonads, especially Xanthomonas euvesicatoria and Xanthomonas citri pv. citri species. Several putative pathogenicity factors were identified, including type III effectors, cell wall-degrading enzymes and clusters encoding protein secretion systems. Specific characteristics in this genome include changes in the xanthomonadin cluster that could explain the lack of typical yellow color in all strains of this pathovar and the presence of 50 regions in the genome with atypical nucleotide composition. The genome sequence was used to predict and evaluate 22 variable number of tandem repeat (VNTR) loci that were subsequently demonstrated as polymorphic in representative Xam strains. Our results demonstrate that Xanthomonas axonopodis pv. manihotis strain CIO151 possesses ten clusters of pathogenicity factors conserved within the genus Xanthomonas. We report 126 genes that are potentially unique to Xam, as well as potential horizontal transfer events in the history of the genome. The relation of these regions with virulence and pathogenicity could explain several aspects of the biology of this pathogen, including its ability to colonize both vascular and non-vascular tissues of cassava plants. A set of 16 robust, polymorphic VNTR loci will be useful to develop a multi-locus VNTR analysis scheme for epidemiological surveillance of this disease.

TALE1 from Xanthomonas axonopodis pv. manihotis acts as a transcriptional activator in plant cells and is important for pathogenicity in cassava plants.

Many plant-pathogenic bacteria suppress pathogen-associated molecular pattern (PAMP)-triggered immunity by injecting effector proteins into the host cytoplasm during infection through the type III secretion system (TTSS). This type III secretome plays an important role in bacterial pathogenicity in susceptible hosts. Xanthomonas axonopodis pv. manihotis (Xam), the causal agent of cassava bacterial blight, injects several effector proteins into the host cell, including TALE1(Xam) . This protein is a member of the Transcriptional Activator-Like effector (TALE) protein family, formerly known as the AvrBs3/PthA family. TALE1(Xam) has 13.5 tandem repeats of 34 amino acids each, as well as two nuclear localization signals and an acidic activation domain at the C-terminus. In this work, we demonstrate the importance of TALE1(Xam) in the pathogenicity of Xam. We use versions of the gene that lack different domains in the protein in structure-function studies to show that the eukaryotic domains at the 3' end are critical for pathogenicity. In addition, we demonstrate that, similar to the characterized TALE proteins from other Xanthomonas species, TALE1(Xam) acts as a transcriptional activator in plant cells. This is the first report of the identification of a TALE in Xam, and contributes to our understanding of the pathogenicity mechanisms employed by this bacterium to colonize and cause disease in cassava.