Biology subjects

Silva, R.

Publications and source records attributed to Silva, R..

At least 19 recordsLinked to original sources

bioRxiv2025

Robustness and fidelity of voltage imaging analysis pipelines

Tracking neuronal voltage changes using fluorescent voltage indicators is rapidly reshaping neuroscientific research. Voltage imaging enables direct visualization of electrical signals from subcellular compartments to large-scale networks, yet requires sophisticated image-analysis procedures. Here, we present a comprehensive study of current voltage imaging analysis pipelines and discuss the experimental conditions for which they are most suitable. We compare strengths and limitations of these pipelines in motion correction, denoising and segmentation routines, and discuss how different signal processing strategies can influence data integrity and interpretation. Our results show that most real-time analyses require GPU-accelerated algorithms and that denoising prior to signal processing is needed for analysis of subcellular dynamics. We conclude that voltage imaging analyses needs to be tailored to different experimental settings: we propose a decision-tree to determine analysis strategies for diverse experimental conditions. Together, these insights pave the way for reproducible, high-fidelity voltage imaging studies.

neuroscience↗

bioRxiv2025

Molecular Insights into ANPEP in Gastric Adenocarcinoma

Alanyl aminopeptidase (ANPEP) has been implicated in various cancers, but its specific role in gastric adenocarcinoma (GC) remains incompletely understood. This study analyzed ANPEP gene expression in gastric cancer (GC), peritumoral tissue (PTT), metaplasia (M), and normal tissue (N). Total RNA was extracted, libraries were prepared and sequenced on the Illumina NextSeq 500. Data was processed using the nf-core/rnaseq pipeline. Transcript quantifications were imported with tximport and normalized using DESeq2. Differential expression (|log2FC| >2; adj. p < 0.05) and Kruskal-Wallis tests identified key genes. ANPEP was significantly upregulated in GC, PTT, and M compared to normal tissue (p < 0.01), suggesting its involvement in early mucosal transformation and malignant progression. Heatmap analysis revealed upregulation of genes related to immune function and oxidative stress, indicating an immunosuppressive and apoptosis-resistant tumor microenvironment. Correlation analyses identified strong positive associations between ANPEP and genes involved in cytoskeletal remodeling, immune modulation, and metabolic regulation, suggesting that ANPEP supports both the invasive potential of tumor cells and the establishment of an immunosuppressive niche. These findings position ANPEP as a promising biomarker for early detection and a candidate for targeted therapies.

cancer biology↗

bioRxiv2025

The improved auxin signalling via entire mutation enhances aluminium tolerance in tomato

Acidic soils limit food production in many developing countries by promoting the solubilization of aluminium (Al) cations. Consequently, roots absorb this metal from soil solution, arresting their growth while reducing water and nutrient uptake. To mitigate the impacts of Al, plants rewire their metabolism and growth, with diverse mechanisms in this process shaped by changes in auxin signalling. Here, we present a comprehensive study on the significance of auxin signalling for Al tolerance. We used tomato mutants with reduced (diageotropica, dgt) and increased (entire) auxin sensitivity to assess the regulation of growth and metabolism in plants coping with Al toxicity. Our results indicated a reduced Al tolerance in the dgt mutant, whereas entire was able to tolerate toxic levels of Al. This contrast can be explained by a differential accumulation of reactive oxygen species (ROS) in the root transition zone, where dgt exhibited more differentiated cells, making the pericycle evident. In contrast, entire showed only slight alterations in the transition zone, with root meristematic cells maintaining a reduced level of cell differentiation, which can be associated with sustained growth under toxic Al levels. These differences were followed by alterations in metabolites related to Al sensitivity in the roots of dgt plants, whereas the entire mutant exhibited only slight metabolic changes. Collectively, our results suggest that genetic modifications to regulate auxin perception have the potential to increase Al tolerance in crops.

plant biology↗

bioRxiv2025

The ganglioside GD3 and its Synthase (ST8SIA1) as novel senescence markers associated with osteoarthritis

Osteoarthritis (OA), is the most common age-induced degenerative joint disease. It is associated with synovial inflammation, subchondral bone remodeling and cartilage degradation. One of the significant emerging causes of OA progression is senescent cell accumulation within the joint compartment during lifespan. Currently, there are no therapeutic approaches nor stratification tools that rely on the senescence burden in OA. In this study, we identified the b-series ganglioside 3 (GD3) as new senescent cell surface marker associated with OA. Joint RNA sequencing analysis revealed an increase expression of the GD3 synthase, ST8SIA1 in cartilage, synovial tissue, and subchondral bone marrow from OA patients compared to healthy donors. Moreover, we revealed a strong correlative association between the expression of ST8SIA1 and GD3 production with senescence hallmarks in an in vitro-induced 3D organotypic OA cartilage model but also with cartilage histological grading scores in human and preclinical murine OA joints. Anti-GD3 cell sorting showed that GD3-positive human OA chondrocytes or human OA synoviocytes are enriched in senescence and SASP markers compared to GD3-negative counterparts confirming that GD3 is a cell surface marker linked to the senescence stage. Intra-articular anti-GD3 antibody delivery in experimental OA model, reduced local expression of senescence and OA markers in association with a protection against OA-induced subchondral bone remodeling. Our research demonstrates a compelling linkage between ST8SIA1 gene, GD3 and senescence in OA pathology, revealing knowledge and perspectives for a better understanding and anti-senescence treatment of OA pathogenesis.

cell biology↗

bioRxiv2025

Evidence for social learning in a granivorous passerine bird, and for its independence from personality

Animals use learning to adaptively adjust their behaviour to conditions taking advantage of previous experiences. While individual learning is advantageous, it includes risks and costs that can be overcome by learning from others. Despite its relevance, the ability to learn from observing others behaviour was tested in only a limited number of birds species, of which only a few feeds mainly on plants. There is still much to be learn what kind of information birds are interested and capable of gathering from conspecifics in the foraging context. We set out to test the social learning skills of a granivorous gregarious species of cardueline finch, the Serin (Serinus serinus), because they likely follow conspecifics cues to forage. We used an observer-demonstrator paradigm where observers were given the opportunity to learn to reach hidden food from observation of demonstrators that were previously trained to perform the task. Almost half of the birds tested were capable of learning (40%) from a conspecific in a colour-food association experiment, and learners were able to remember the association after fifteen days. Also, almost half of the birds tested for this revealed to be capable of reversal learning. The ability to learn was not influenced by sex or age, of both demonstrators and learners, but learners had longer wings than non-learners. We investigated whether personality could explain the differences in learning ability of these birds. We assessed individual boldness and sociability through the novel object test and mirror personality tests respectively. Although we found repeatability those personality traits we found no association with social learning ability.

animal behavior and cognition↗

bioRxiv2024

Comparing machine learning models for predicting mutation status in Acute Myeloid Leukemia patients using RNA-seq data

Acute Myeloid Leukemia (AML) is a highly heterogeneous disease. The current AML classifications are based mainly on molecular markers, including cytogenetics features, fusion genes, and the presence or absence of mutations. In this study, we investigated mutation status in AML patients through RNA-seq data in link with differential gene expression. We applied seven machine learning algorithms to identify the presence or absence of NPM1, IDH1/IDH2, and FLT3-ITD mutations, reaching 95%, 93%, and 87% accuracy, respectively. In each case, the best performing models were complex models, suggesting highly complex biological processes at work behind AML.

bioinformatics↗

bioRxiv2024

Heat Stress on the brown Seaweed Ascophyllum nodosum: differential population sensitivity to future climate.

Accurate forecasts of the biological impacts of climate change require a better understanding of how small-scale temperature variability affects individual physiology and population dynamics. But doing so for intertidal species with large distribution ranges, while also accounting for the effect of local adaptation, presents numerous technical challenges. Here, we assessed the macroecological consequences of thermal stress on the cold-adapted brown seaweed Ascophyllum nodosum across its European distribution. We collected specimens from ten populations spanning latitudes 41{degrees}N to 60{degrees}N and subjected them to simulated intertidal heat stress using a novel, custom-built experimental setup that replicated realistic conditions, including tidal cycles, light conditions, and temperature trajectories based on in situ data. Our factorial design comprised eight experimental treatments, combining two high-tide water temperatures (15 {degrees}C and 20.5 {degrees}C) with four low-tide peak temperatures (28.5 {degrees}C to 40.5 {degrees}C). Physiological performance was evaluated through measurements of growth, mortality, and oxygen production. Results indicate that thermal stress is more closely associated with the magnitude of temperature change between high and low tides rather than the absolute maximum temperatures reached. Algae exposed to warmer water temperatures (20.5 {degrees}C) consistently outperformed those in colder water (15 {degrees}C), suggesting that cold upwelled waters at the species southern limit may not be essential for survival. Southern populations demonstrated higher resilience to thermal stress than central and northern counterparts. Integrating these physiological responses with climate projections, we employed demographic models to forecast long-term population dynamics. The models predict that future climatic conditions could exceed the thermal resilience of specific populations, leading to uneven impacts across the European distribution of the species. Notwithstanding, range contractions may occur at the warm edge of the distribution, where populations, though more resilient to thermal stress, could still be overwhelmed by the pace of warming. This study underscores the importance of realistic experimental simulations in evaluating species thermal tolerance and highlights the potential for climate change to differentially impact populations along large latitudinal gradients.

ecology↗

bioRxiv2024

SARS-CoV-2 papain-like protease activates nociceptors to drive sneeze and pain

SARS-CoV-2, the virus responsible for COVID-19, triggers symptoms such as sneezing, aches and pain.1 These symptoms are mediated by a subset of sensory neurons, known as nociceptors, that detect noxious stimuli, densely innervate the airway epithelium, and interact with airway resident epithelial and immune cells.2-6 However, the mechanisms by which viral infection activates these neurons to trigger pain and airway reflexes are unknown. Here, we show that the coronavirus papain-like protease (PLpro) directly activates airway-innervating trigeminal and vagal nociceptors in mice and human iPSC-derived nociceptors. PLpro elicits sneezing and acute pain in mice and triggers the release of neuropeptide calcitonin gene-related peptide (CGRP) from airway afferents. We find that PLpro-induced sneeze and pain requires the host TRPA1 ion channel that has been previously demonstrated to mediate pain, cough, and airway inflammation.7-9 Our findings are the first demonstration of a viral product that directly activates sensory neurons to trigger pain and airway reflexes and highlight a new role for PLpro and nociceptors in COVID-19.

neuroscience↗

bioRxiv2023

Characterization of peroxidasin expression in histologically normal human adult and fetal kidney tissue

Peroxidasin (PXDN) is an enzyme of the peroxidase family that plays a critical role in extracellular matrix (ECM) formation and tissue development. In the kidney, very few studies using animal cells suggested that PXDN may have a role in the maintenance of the structural and functional integrity of the renal ECM. Still, the normal expression and (patho)physiological roles of PDXN in the mature and developing human kidney remain unknown. In this work we used fluorescent immunohistochemistry and advanced microscopy and image processing methodologies to perform a quantitative characterization of PXDN expression in the different anatomic compartments of histologically normal kidney tissue, obtained from adult nephrectomy specimens, and from postmortem fetal and neonatal kidney specimens (excluding death by kidney disease and genitourinary developmental anomalies). Results show that PXDN is expressed in all mature kidney compartments, but at significantly higher levels in tubular epithelial cells, particularly in the distal tubules. A similar PXDN expression pattern was observed in the developing kidney, as early as the in the comma-shaped-body stage. In the fetal kidney, PXDN was diffusely expressed in the branches of the ureteric bud but not in the cells of the metanephric blastema. This is the first demonstration that PXDN is differentially expressed in histologically normal human renal parenchyma, exhibiting a remarkably consistent pattern of predominant tubular expression since the early stages of metanephrogenesis This data suggests a relevant, compartment-specific, role of PXDN in nephrogenesis and in the kidney physiology, highlighting a main role in tubular functions, that is worth further investigation.

physiology↗

bioRxiv2022

An SNF2 helicase-like protein links mitotic transcription termination to sister chromatid resolution

AO_SCPLOWBSTRACTC_SCPLOWMitotic chromatin is largely assumed incompatible with transcription due to changes in the transcription machinery and chromosome architecture. However, the mechanisms of mitotic transcriptional inactivation and their interplay with chromosome assembly remain largely unknown. By monitoring ongoing transcription in Drosophila early embryos, we reveal that eviction of nascent mRNAs from mitotic chromatin occurs after substantial chromosome compaction and is not promoted by condensin I. Instead, we show that the timely removal of transcripts from mitotic chromatin is driven by the SNF2 helicase-like protein Lodestar (Lds), identified here as a modulator of sister chromatid cohesion defects. In addition to transcriptional termination, we uncovered that Lds cooperates with Topoisomerase 2 to ensure efficient sister chromatid resolution and mitotic fidelity. We conclude that mitotic transcriptional termination is not a passive consequence of cell cycle progression and/or chromosome compaction but occurs via dedicated mechanisms with functional parallelisms to sister chromatid resolution.

cell biology↗

bioRxiv2022

The Nucleocapsid Protein Of SARS-CoV-2, Combined With ODN-39M, Is A Potential Component For An Intranasal Bivalent Pancorona Vaccine

Despite the rapid development of vaccines and their reported efficacy for controlling the COVID-19 waves, two key challenges remain: the scope of the immunity against upcoming variants and zoonosis events, and the induction of mucosal immunity able to clear the virus in the upper respiratory tract for halting the transmission. The present study is aiming at assessing a potential component for a new generation of vaccines so as to overcome such limitations. The recombinant nucleocapsid (N) protein from SARS-CoV-2 Delta variant was combined with a phosphodiester backbone CpG ODN (ODN-39M), forming high molecular weight aggregates. The evaluation of its immunogenicity in Balb/C mice revealed that only administration by intranasal route induced a systemic cross-reactive Cell-Mediated-Immunity (CMI). In turn, this combination was able to induce anti-N IgA in lungs, which along with the specific IgG in sera and CMI in spleen, resulted cross-reactive against the nucleocapsid protein of SARS-CoV-1. Furthermore, the nasal administration of the N+ODN-39M preparation combined with the RBD Delta protein, as inductor of neutralizing Abs, enhanced the local and systemic immune response against RBD with a modulation toward a Th1 pattern. Taken together, these results make the N+ODN-39M preparation a suitable component for a future intranasal pancorona vaccine against Sarbecoviruses. Particularly, the bivalent vaccine formulation N+ODN-39M+RBD could be used as an effective nasal booster in previously vaccinated population.

immunology↗

bioRxiv2021

Identification of a conserved neutralizing epitope present on spike proteins from highly pathogenic coronaviruses

Three pathogenic human coronaviruses have emerged within the last 20 years, with SARS-CoV-2 causing a global pandemic. Although therapeutic antibodies targeting the SARS-CoV-2 spike currently focus on the poorly conserved receptor-binding domain, targeting essential neutralizing epitopes on the more conserved S2 domain may provide broader protection. We report an antibody binding an epitope conserved in the pre-fusion core of MERS-CoV, SARS-CoV and SARS-CoV-2 spike S2 domains. Antibody 3A3 binds a conformational epitope with ~2.5 nM affinity and neutralizes spike from SARS-CoV, SARS-CoV-2 and variants of concern in in vitro pseudovirus assays. Hydrogen-deuterium exchange mass spectrometry identified residues 980-1006 in the flexible hinge region at the S2 apex as the 3A3 epitope, suggesting 3A3 prevents the S2 conformational rearrangements required for conversion to the spike post-fusion state and virus-host cell fusion. This work defines a conserved vulnerable site on the SARS-CoV-2 S2 domain and guides the design of pan-protective spike immunogens.

biochemistry↗

bioRxiv2020

geneRFinder: gene finding in distinct metagenomic data complexities

MotivationMicrobes perform a fundamental economic, social and environmental role in our society. Metagenomics makes it possible to investigate microbes in their natural environments (the complex communities) and their interactions. The way they act is usually estimated by looking at the functions they play in those environments and their responsibility is measured by their genes. The advances of next-generation sequencing technology have facilitated metagenomics research however it also create a heavy computational burden. Large and complex biological datasets are available as never before. There are many gene predictors available which can aid gene annotation process though they lack of handling appropriately metagenomic data complexities. There is no standard metagenomic benchmark data for gene prediction. Thus, gene predictors may inflate their results by obfuscating low false discovery rates. ResultsWe introduce geneRFinder, a ML-based gene predictor able to outperform state-of-the-art gene prediction tools across this benchmark by using only one pre-trained Random Forest model. Average prediction rates of geneRFinder differed in percentage terms by 54% and 64%, respectively, against Prodigal and FragGeneScan while handling high complexity metagenomes. The specificity rate of geneRFinder had the largest distance against FragGeneScan, 79 percentage points, and 66 more than Prodigal. According to McNemars test, all percentual differences between predictors performances are statistically significant for all datasets with a 99% confidence interval. ConclusionsWe provide geneRFinder, a approach for gene prediction in distinct metagenomic complexities, available at github.com/railorena/geneRFinder, and also we provide a novel, comprehensive benchmark data for gene prediction -- which is based on The Critical Assessment of Metagenome Interpretation (CAMI) challenge, and contains labeled data from gene regions - avaliable at sourceforge.net/p/generfinder-benchmark.

bioinformatics↗

bioRxiv2020

Aspergillus fumigatus G-protein coupled receptors GprM and GprJ are important for the regulation of the cell wall integrity pathway, secondary metabolite production, and virulence

G-protein coupled receptors (GPCRs) are extracellular signalling receptors that sense environmental cues to coordinate a biological response. Fungi sense their environment primarily through GPCR-mediated signalling pathways, which in turn regulate fungal development, metabolism, virulence and mycotoxin biosynthesis. A. fumigatus is an important human pathogen that causes aspergillosis, a heterogeneous group of diseases that presents a wide range of clinical manifestations. Here, we investigate in detail the role of the GPCRs GprM and GprJ in growth and gene expression. GprM and GprJ are important for melanin production and the regulation of the cell wall integrity (CWI) pathway. Overexpression of gprM and gprJ causes a 20 and 50% reduction in growth rate when compared to the wild-type (WT) strain, and increases sensitivity to cell wall-damaging agents. Phosphorylation of the CWI protein kinase MpkA is increased in the {Delta}gprM and {Delta}gprJ strains and decreased in the overexpression mutants when compared to the WT strain. Furthermore, differences in cell wall polysaccharide concentrations and organization were observed in these strains. RNA-sequencing suggests that GprM and GprJ negatively regulate genes encoding secondary metabolites (SMs). Mass spectrometry analysis confirmed that the production of fumagillin, pyripyropene, fumigaclavine C, fumiquinazoline, and fumitremorgin is reduced in the {Delta}gprM and {Delta}gprJ strains, and that this regulation occurs, at least partially, through the activation of MpkA. Overexpression of grpM also resulted in the regulation of many transcription factors, with AsgA predicted to function downstream of GprM and MpkA signalling. Finally, we show that the {Delta}gprM and {Delta}gprJ mutants are reduced in virulence in the Galleria mellonella insect model of invasive aspergillosis. This work further contributes to unravelling functions of A. fumigatus GPCRs and shows that GprM and GprJ are essential for CWI, secondary metabolite production and virulence. Author summaryA. fumigatus is the main ethiological agent of invasive pulmonary aspergillosis, a life-threatening fungal disease that occurs in severely immuno-compromised humans. Withstanding the host environment is essential for A. fumigatus virulence and sensing of extracellular cues occurs primarily through G-protein coupled receptors (GPCRs) that activate signal transduction pathways, which in turn regulate fungal development, metabolism, virulence and mycotoxin biosynthesis. The A. fumigatus genome encodes 15 putative classical GPCRs, with only three having been functionally characterized to date. In this work, we show that the two GPCRs GprM and GprJ regulate the phosphorylation of the mitogen-activated protein kinase MpkA and thus control the regulation of the cell wall integrity pathway. GprM and GprJ are also involved in the regulation of the production of the secondary metabolites fumagillin, pyripyropene, fumigaclavine C, fumiquinazoline, melanin, and fumitremorgin and this regulation partially occurs through the activation of MpkA. Furthermore, GprM and GprJ are important for virulence in the insect model Galleria mellonella. This work therefore functionally characterizes two GPCRs and shows how they regulate several intracellular pathways that have been shown to be crucial for A. fumigatus virulence.

microbiology↗

bioRxiv2020

MORPHO-MOLECULAR MECHANISMS STUDY OF PHOTODYNAMIC THERAPY AND CURCUMIN LARVICIDE ACTION ON WILD MOSQUITOES LARVAE OF GENUS Aedes

IntroductionUntil the first two weeks of October 2019, 1.489,457 probable dengue cases have been reported in Brazil, with an incidence rate of 708.8 cases per 100 thousand inhabitants. Still in 2019, in the same period, 123.407 probable cases of chikungunya were reported, with 15 deaths confirmed by clinical and epidemiological criteria. Regarding Zika, in that period, 10.441 probable cases were recorded, been the northeast region with the highest number of notifications, followed by the midwest one. It is well known that current policies to control the vectors of those arboviruses are not effective. Studies for use of light-activated photosensitizers as an alternative to conventional insecticides for sustainable control of mosquitoes vector such as Aedes (dengue, yellow fever, chikungunya, zika), Anopheles (malaria), Culex (yellow fever) can already be found showing advantages over conventional insecticides (efficacy, safety, non-mutagenicity and fast degradation). ObjectiveTo evaluate the effectiveness of Photodynamic Therapy (PDT), mediated by curcumin and blue LED (460nm) in mortality of wild mosquitoes larvae of genus Aedes and also to verify, through confocal microscopy, how the photosensitizer internalizes in larvae organism. In addition to evaluating the action of PDT on the larvae with Raman spectroscopy and histological technique. Materials and methodsOvitraps were placed in the city of Vitoria da Conquista, Bahia, and the larvae collected in stages L2 and L3 were fed for 24 hours with curcumin in concentrations of 10, 20 and 50% mixed with fish feed and then subjected to irradiation with blue LED for 2h (22mW / cm2 and 158.4 J / cm2). The larvae were placed in a container with dechlorinated water and mortality was monitored for 24 and 48 hours. Control groups in which only the larvae were exposed to blue LED for 2 hours and in which the larvae were only fed with fish feed mixed with curcumin (10, 20 and 50%) were included in the study, in addition to the group without treatment. All experiments were repeated after a 2-month interval to confirm the results, totaling 240 tests (tests 1 and 2, n = 15) between groups PDT 10%, PDT 20%, PDT 50%, curcumin 10%, curcumin 20%, curcumin 50%, blue LED and untreated group. The larvae belonging to the PDT 20% group, 20% curcumin, blue LED and control were submitted to histological slides, confocal microscopy and Raman spectroscopy. Larvae mortality rates were compared between groups using univariate descriptive analysis. ResultsAll PDT groups showed larvicidal activity, with the PDT group 20% showing the highest larval mortality in the shortest time. The images from confocal microscopy by laser scanning showed that curcumin was distributed throughout the digestive system of larvae and the analysis by Raman microspectroscopy have shown patterns of alteration and cell death, corroborated by histological sections. ConclusionIt was concluded that PDT in all concentrations was effective in larval mortality, with PDT 20% having the best activity with mortality of 100% in 24 hours.

bioengineering↗

bioRxiv2020

Hype versus hope: Deep learning encodes more predictive and robust brain imaging representations than standard machine learning

Previous successes of deep learning (DL) approaches on several complex tasks have hugely inflated expectations of their power to learn subtle properties of complex brain imaging data, and scale to large datasets. Perhaps as a reaction to this inflation, recent critical commentaries unfavorably compare DL with standard machine learning (SML) approaches for the analysis of brain imaging data. Yet, their conclusions are based on pre-engineered features which deprives DL of its main advantage: representation learning. Here we evaluate this and show the importance of representation learning for DL performance on brain imaging data. We report our findings from a large-scale systematic comparison of SML approaches versus DL profiled in a ten-way age and gender-based classification task on 12,314 structural MRI images. Results show that DL methods, if implemented and trained following the prevalent DL practices, have the potential to substantially improve compared to SML approaches. We also show that DL approaches scale particularly well presenting a lower asymptotic complexity in relative computational time, despite being more complex. Our analysis reveals that the performance improvement saturates as the training sample size grows, but shows significantly higher performance throughout. We also show evidence that the superior performance of DL is primarily due to the excellent representation learning capabilities and that SML methods can perform equally well when operating on representations produced by the trained DL models. Finally, we demonstrate that DL embeddings span a comprehensible projection spectrum and that DL consistently localizes discriminative brain biomarkers, providing an example of the robustness of prediction relevance estimates. Our findings highlight the presence of non-linearities in brain imaging data that DL frameworks can exploit to generate superior predictive representations for characterizing the human brain, even with currently available data sizes.

neuroscience↗

bioRxiv2019

Chagas disease awareness and socioeconomic characteristics of Bolivian immigrants living in Sao Paulo, Brazil.

In this study, part of a research project on Chagas disease among residents of Bolivia in Sao Paulo, we describe socioeconomic characteristics, knowledge about the disease and access to health services. A structured questionnaire was applied to a sample of 472 Bolivian adults (> 18 years) living in Sao Paulo enrolled in the Barra Funda School Health Center. The median age of participants was 28.5 years, 75.0% from the Bolivian department of La Paz, who were living in Sao Paulo for an average of 5.8 years. Regarding knowledge about the disease and exposure to certain risk factors, 47.7% indicated familiarity with the vector, 23.9% had seen vinchuca in their homes in Bolivia and 6.4% reported having been bitten by a triatomine. The conditions of living in rural areas in Bolivia or in other department than La Paz, have a relative with illness, high school graduation and have seen or been bitten by a vinchuca were significantly associated with the knowledge of the vector. This study provides a view on migration that has important implications for the distribution of Chagas disease and access to health care by providing subsidies for proposing public health policies.\n\nAuthor summaryThis article expresses part of the results of a research project called \"Chagas disease in a population of Bolivian immigrants in Sao Paulo: an analysis of the prevalence of Trypanosoma cruzi infection and morbidity of Chagas disease, knowledge of the population about the disease and access to different levels of health care\". The problem of chronic Chagas disease occurs in many countries, including those not considered endemic, as a result of population movements, mainly by immigration due to urbanization which has led to its globalization. It is now considered an emerging disease with significant potential for transmission via blood transfusions, organ transplants and congenital via, in the absence of appropriate strategies in terms of public health, as well as reactivation of chronic disease in urban centers. Its no different this phenomenon to the city of Sao Paulo. This study analyzed the sociodemographic inserts, labor, migration and knowledge about Chagas disease and its impact on personal, family and professional life of Bolivian immigrants living in Sao Paulo.

scientific communication and education↗

bioRxiv2019

Evaluation of Trichoderma harzianum mutant lines in the resistance induction against white mold and growth promotion of common bean

Genetic engineering has brought improvements of Trichoderma species for biotechnological processes such as agriculture. It has previously been reported that sm1 and aquaglyceroporin genes from Trichoderma harzianum are strongly expressed during pathogens biocontrol. We have previously shown that Sm1 plays a significant role in plant disease resistance and aquaporin (AQP) regulate physiological processes and responses related to water stress. Here, we report the evaluation of mutant lines with sm1 (deleated) and aqp (overexpressed) in Phaseoulus vulgaris growth promotion and disease resistance induction. It was investigated plants physiological and biochemical responses, plant growth promotion and biocontrol of Sclerotinia sclerotiorum, the causal agent of white mold. Treatments included Trichoderma harzianum wyld type, mutant line overexpressing aquaporin (Aqua), and deleted{Delta} Epl1mutant line. Our results demonstrated that Aqua mutant line increased leaf area in 25%, in comparison to non-treated plants. It also differed from other treatments, in comparison to plants with treatments ALL-42 and{Delta} Epl1, which increased 28% and 91%, respectively (Isso e abstract, ta confuse e extensor. Specific activity of {beta}-1.3 glucanase was higher in plants treated with T. harzianum {Delta}Epl1 mutant isolate, in leaves and roots respectively with 2.07 Umg-1 and 2.57 Umg-1. Plants inoculated or not with S. sclerotiorum presented with 2.27 Umg-1 and 2.34 Umg-1 of {beta}-1.3 glucanase on average, respectively, but enzymatic activity was higher on leaves when compared to the roots. The Aqua mutant demonstrated excellent growth promoting properties. Both mutants of T. harzianum do not induce resistance to white mold on common bean plants.

microbiology↗