Disentangling vehicular emission impact on urban air pollution using ethanol as a tracer

The Sao Paulo Metropolitan Area is a unique case worldwide due to the extensive use of biofuel, particularly ethanol, by its large fleet of nearly 8 million cars. Based on source apportionment analysis of Organic Aerosols in downtown Sao Paulo, and using ethanol as tracer of passenger vehicles, we have identified primary emissions from light-duty-vehicles (LDV) and heavy-duty-vehicles (HDV), as well as secondary process component. Each of those factors mirror a relevant primary source or secondary process in this densely occupied area. Using those factors as predictors in a multiple linear regression analysis of a wide range of pollutants, we have quantified the role of primary LDV or HDV emissions, as well as atmospheric secondary processes, on air quality degradation. Results show a significant contribution of HDV emissions, despite contributing only about 5% of vehicles number in the region. The latter is responsible, for example, of 40% and 47% of benzene and black carbon atmospheric concentration, respectively. This work describes an innovative use of biofuel as a tracer of passenger vehicle emissions, allowing to better understand the role of vehicular sources on air quality degradation in one of most populated megacities worldwide

ATLANTIC-PRIMATES: a dataset of communities and occurrences of primates in the Atlantic Forests of South America

Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1–6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km 2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km 2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. Please cite this Data Paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. © 2018 by the The Authors. Ecology © 2018 The Ecological Society of Americ

Expression of KRAS mutation and loss of a c-type lectin cooperates to sustain a bacterial-induced immune-suppressive microenvironment in right-sided colon cancer.

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Biomass burning in the Amazon region: Aerosol source apportionment and associated health risk assessment

International audienceThe Brazilian Amazon represents about 40% of the world's remaining tropical rainforest. However, human activities have become important drivers of disturbance in that region. The majority of forest fire hotspots in the Amazon arc due to deforestation are impacting the health of the local population of over 10 million inhabitants. In this study we characterize western Amazonia biomass burning emissions through the quantification of 14 Polycyclic Aromatic Hydrocarbons (PAHs), Organic Carbon, Elemental Carbon and unique tracers of biomass burning such as levoglucosan. From the PAHs dataset a toxic equivalence factor is calculated estimating the carcinogenic and mutagenic potential of biomass burning emissions during the studied period. Peak concentration of PM10 during the dry seasons was observed to reach 60 μg m−3 on the 24 h average. Conversely, PM10 was relatively constant throughout the wet season indicating an overall stable balance between aerosol sources and sinks within the filter sampling resolution. Similar behavior is identified for OC and EC components. Levoglucosan was found in significant concentrations (up to 4 μg m−3) during the dry season. Correspondingly, the estimated lung cancer risk calculated during the dry seasons largely exceeded the WHO health-based guideline. A source apportionment study was carried out through the use of Absolute Principal Factor Analysis (APFA), identifying a three-factor solution. The biomass burning factor is found to be the dominating aerosol source, having 75.4% of PM10 loading. The second factor depicts an important contribution of several PAHs without a single source class and therefore was considered as mixed sources factor, contributing to 6.3% of PM10. The third factor was mainly associated with fossil fuel combustion emissions, contributing to 18.4% of PM10. This work enhances the knowledge of aerosol sources and its impact on climate variability and local population, on a site representative of the deforestation which occupies a significant fraction of the Amazon basin

Involvement of the NLRC5 / MHC class I axis in human colorectal cancer immune surveillance

International audienceMost of patients with colorectal cancer (CRC) without microsatellite instability fail torespond to immune checkpoint blockade (ICB) through poorly understood changes in thetumor microenvironment. Recently, we provided evidence that the tonus of tumor infiltratingT lymphocytes (TILs) is associated to the intra-tumoral activity of Caspase-1 (doi:10.3390/cancers13020189). Bulk RNA-seq analysis of CRC revealed a greater expression level of NLRfamily CARD domain containing 5 (NLRC5) in tumors with a detectable Caspase-1 activity.Given that NLRC5 is a regulator of major histocompatibility complex class I (MHC-I) antigenpresentation, we postulated that NLRC5 may modulate cancer immune surveillance andresponsiveness to ICB. We thereby evaluated the significance of the intratumoral changesin NLRC5 expression in several cohorts of patients. We show that NLRC5 is a favorableprognostic factor of overall survival in 100 CRC and of responsiveness to ICB in 45 metastaticCRC. In agreement, NLRC5 expression in KRAS wild type CRC is of better prognosis andpositively correlates with PD1/PD-L1 axis. Conversely, a negative correlation is observedbetween PRMT5, an epigenetic modifier that represses NLRC5 expression, and PD-1/PD-L1axis. Finally, functional studies using co-cultures of TILs isolated from CRC fragments andcolonic cancer cell lines show that enforced expression of NLRC5 in tumor cells enhancesthe cytotoxic activity of CD8+ TILs (cytokine production, degranulation), via a MHC-I-dependent mechanism. Overall, our findings suggest that NLRC5 could be a valuablebiomarker in CRC and that increasing the NLRC5/MHC-I axis in tumor cells could enhanceanti-tumor immunity and immunotherapeutic responses

Reg3A and glycerophospholipids metabolites axis promote an immune-suppressive microenvironment in right-sided colon cancer

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Reg3A and glycerophospholipids metabolites axis promote an immune-suppressive microenvironment in right-sided colon cancer

International audienc

Bacterial colibactin-induced lipid accumulation and loss of a c-type lectin cooperates for supporting an immune-suppressive microenvironment in right-sided colon cancer

International audienceRight-sided colon cancer (RCC) patients exhibit difference in the microbiota organization in relation to left-sided colon cancer and has a worse prognosis. Among several species of bacteria associated with colon cancer, colibactin-producing by Escherichia coli (CoPEC) are attracting attention. However, if CoPEC contributes to tumor lipid metabolism remains incompletely understood. Herein, we revealed that CoPEC is negatively correlated with human regenerating family member 3 alpha gene (REG3A) expression and trigger reprogramming lipid metabolism, which exacerbates accumulation of glycerophospholipids. Notably, APC mutation and metabolic consensus molecular subtype (CMS3) are predominant in RCC, especially in patients colonized by CoPEC. While SFRP2 expression is increased in these tumors, CD8+ T cells were reduced. In addition, human tumors have similarities to mice tumors. In particular, mRNAs encoding immunoglobulins heavy chains were clearly increased in both models with low Reg3A expression. Taken together, CoPEC associated with REG3A is promising as a biomarker in cancer therapy