Distinct bacterial communities across a gradient of vegetation from a preserved Brazilian Cerrado

The Cerrado biome in the Sete Cidades National Park, an Ecological Reserve in Northeastern Brazil, has conserved its native biodiversity and presents a variety of plants found in other savannas in Brazil. Despite this finding the soil microbial diversity and community structure are poorly understood. Therefore, we described soil bacterial diversity and distribution along a savanna vegetation gradient taking into account the prevailing environmental factors. The bacterial composition was retrieved by sequencing a fragment of the 16S ribosomal RNA gene. The bacterial operational taxonomic units (OTUs) were assigned to 37 different phyla, 96 classes, and 83 genera. At the phylum level, a core comprised by Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes, Verrucomicrobia and Planctomycetes, was detected in all areas of Cerrado. ‘Cerrado stricto sensu’ and ‘Cerradao’ share more similarities between edaphic properties and vegetation and also present more similar bacterial communities, while ‘Floresta decidual’ and ‘Campo graminoide’ show the largest environmental differences and also more distinct bacterial communities. Proteobacteria (26%), Acidobacteria (21%) and Actinobacteria (21%) were the most abundant phyla within the four areas. All the samples present similar bacteria richness (alpha diversity) and the observed differences among them (beta diversity) were more related to the abundance of specific taxon OTUs compared to their presence or absence. Total organic C, N and P are the main abiotic factors structuring the bacterial communities. In summary, our findings show the bacterial community structure was clearly different across the Cerrado gradient, but that these environments share a bacterial phylum-core comprising Proteobacteria, Acidobacteria, Actinobacteria, Verrucomicrobia and Planctomycetes with other Brazilian savannas.     

Relationship between the Bolsa Família national cash transfer programme and suicide incidence in Brazil: A quasi-experimental study

BackgroundSocioeconomic factors have been consistently associated with suicide, and economic recessions are linked to rising suicide rates. However, evidence on the impact of socioeconomic interventions to reduce suicide rates is limited. This study investigates the association of the world’s largest conditional cash transfer programme with suicide rates in a cohort of half of the Brazilian population.Methods and findingsWe used data from the 100 Million Brazilian Cohort, covering a 12-year period (2004 to 2015). It comprises socioeconomic and demographic information on 114,008,317 individuals, linked to the “Bolsa Família” programme (BFP) payroll database, and nationwide death registration data. BFP was implemented by the Brazilian government in 2004. We estimated the association of BFP using inverse probability of treatment weighting, estimating the weights for BFP beneficiaries (weight = 1) and nonbeneficiaries by the inverse probability of receiving treatment (weight = E(ps)/(1-E(ps))). We used an average treatment effect on the treated (ATT) estimator and fitted Poisson models to estimate the incidence rate ratios (IRRs) for suicide associated with BFP experience. At the cohort baseline, BFP beneficiaries were younger (median age 27.4 versus 35.4), had higher unemployment rates (56% versus 32%), a lower level of education, resided in rural areas, and experienced worse household conditions. There were 36,742 suicide cases among the 76,532,158 individuals aged 10 years, or older, followed for 489,500,000 person-years at risk. Suicide rates among beneficiaries and nonbeneficiaries were 5.4 (95% CI = 5.32, 5.47, p < 0.001) and 10.7 (95% CI = 10.51, 10.87, p < 0.001) per 100,000 individuals, respectively. BFP beneficiaries had a lower suicide rate than nonbeneficiaries (IRR = 0.44, 95% CI = 0.42, 0.45, p < 0.001). This association was stronger among women (IRR = 0.36, 95% CI = 0.33, 0.38, p < 0.001), and individuals aged between 25 and 59 (IRR = 0.41, 95% CI = 0.40, 0.43, p < 0.001). Study limitations include a lack of control for previous mental disorders and access to means of suicide, and the possible under-registration of suicide cases due to stigma.ConclusionsWe observed that BFP was associated with lower suicide rates, with similar results in all sensitivity analyses. These findings should help to inform policymakers and health authorities to better design suicide prevention strategies. Targeting social determinants using cash transfer programmes could be important in limiting suicide, which is predicted to rise with the economic recession, consequent to the Coronavirus Disease 2019 (COVID-19) pandemic.

In a quasi-experimental study, Daiane Borges Machado and colleagues investigate the association between rates of suicide and the Bolsa Familia cash transfer program in the 100 Million Brazilian Cohort.     

Inhibition by a nonmetabolized analogue of L-leucine of protein biosynthesis in tumoral pancreatic islet cells

The effect of L-leucine, its deaminated metabolite 2-ketoisocaproate and its nonmetabolized analogue b(+/-)2-aminobicyclo[2,2,1]-heptane-2-carboxylic acid (BCH) upon protein labelling was examined in tumoral islet cells (RINm5F line) exposed to L-[4-3H]phenylalanine or L-[3-3H]serine. The interpretation of the results, in terms of changes in biosynthetic activity, was obscured by a possible interference of the tested nutrients with the uptake and further metabolism of the tracer tritiated amino acids. Nevertheless, when the cells were preincubated with the nutrient secretagogues and then incubated in the sole presence of L-[3-3H]serine, BCH, but not L-leucine or 2-ketoisocaproate, still inhibited protein labelling, this coinciding with a decrease in the ratio between TCA-precipitable and total radioactivity in the RINm5F cells. The inhibitory action of BCH was antagonized, to a limited extent, by D-glucose. It is proposed that BCH could be used as a tool to interfere with the function and growth of insulinoma cells.     

Thrombotic microangiopathy in oncology – a review

Thrombotic microangiopathy is a syndrome triggered by a wide spectrum of situations, some of which are specific to the Oncology setting. It is characterized by a Coombs-negative microangiopathic haemolytic anemia, thrombocytopenia and organ injury, with characteristic pathological features, resulting from platelet microvascular occlusion.TMA is rare and its cancer-related subset even more so. TMA triggered by drugs is the most common within this group, including classic chemotherapy and the latest targeted therapies. The neoplastic disease itself and hematopoietic stem-cell transplantation could also be potential triggers.Evidence-based medical guidance in the management of cancer-related TMA is scarce and the previous knowledge about primary TMA is valuable to understand the disease mechanisms and the potential treatments.Given the wide spectrum of potential causes for TMA in cancer patients, the aim of this review is to gather the vast information available. For each entity, pathophysiology, clinical features, therapeutic approaches and prognosis will be covered.     

Homogeneously sized groups increase aggressive interaction and affect social stress in Thai strain Nile tilapia (Oreochromis niloticus)

Social fish raised in farms are usually kept in groups of similar-sized individuals. However, social animals of similar size typically have similar fighting ability, which increases aggressive interaction for social rank establishment, as well as social stress. We compared Thai strain Nile tilapia fish, Oreochromis niloticus (L.), held under two treatments: (1) The Homogeneous one, with five adult male fish of similar size and (2) the Heterogeneous treatment with five adult males of different sizes. We recorded the frequency of aggressive interactions and checked social stability and stress levels (cortisol) after five days in the groups. Grouping similar sized Thai Nile tilapia increased the aggressive interactions and delayed rank stability with increased body injuries as a consequence. Homogeneous-sized individuals showed a similar level of stress while heterogeneous-sized individuals showed different stress levels with dominants being more stressed than subordinates. The data indicate that the practice of selecting fish of similar size in aquaculture management could reduce the welfare of social fish and that the effect is observed in different lineages.     

Immunopositivity for Siglec-15 in gastric cancer and its association with clinical and pathological parameters

The sialic acid-binding immunoglobulin-type lectin Siglec-15 is a promising target for cancer immunotherapy in several tumor types. The present study aimed to investigate Siglec-15 expression in gastric cancer (GC) patient tissues and to evaluate its clinical value. Siglec-15 expression was evaluated by immunohistochemistry in 71 patients. Siglec-15 staining was observed in tumor cells of 53 (74.64%) patients, with significant association with histologic classification and angiolymphatic invasion (p<0.05). Immunohistochemistry analysis also detected Siglec-15 in tumor-associated stroma cells (macrophages/myeloid cells). There was no significant association with outcome parameters. Siglec-15 expression in well differentiated histological GC tissues and in the tumor microenvironment are potential targets to be further investigated as a novel prognostic factor for GC.Key words: Siglec, sialic acid, immunohistochemistry, clinical-pathological analyses     

Caco-2 cells infected with rotavirus release extracellular vesicles that express markers of apoptotic bodies and exosomes

Previously, we showed that infecting human intestinal epithelial cells (Caco-2) with rotavirus (RV) increases the release of extracellular vesicles (EVs) with an immunomodulatory function that, upon concentration at 100,000×g, present buoyant densities on a sucrose gradient of between 1.10 to 1.18 g/ml (characteristic of exosomes) and higher than 1.24 g/ml (proposed for apoptotic bodies). The effect of cellular death induced by RV on the composition of these EV is unknown. Here, we evaluated exosome (CD63, Hsc70, and AChE) and apoptotic body (histone H3) markers in EVs isolated by differential centrifugation (4000×g, 10,000×g, and 100,000×g) or filtration/ultracentrifugation (100,000×g) protocols. When we infected cells in the presence of caspase inhibitors, Hsc70 and AChE diminished in EVs obtained at 100,000×g, but not in EVs obtained at 4000×g or 10,000×g. In addition, caspase inhibitors decreased CD63 and AChE in vesicles with low and high buoyant densities. Without caspase inhibitors, RV infection increased exosome markers in all of the EVs obtained by differential centrifugation. However, CD63 preferentially localized in the 100,000×g fraction and H3 only increased in EVs concentrated at 100,000×g and with high buoyant densities on a sucrose gradient. Thus, RV infection increases the release of EVs that, upon concentration at 100,000×g, are composed by exosomes and apoptotic bodies, which can partially be separated using sucrose gradients.     

Dissolving microneedles containing aminolevulinic acid improves protoporphyrin IX distribution

One important limitation of topical photodynamic therapy (PDT) is the limited tissue penetration of precursors. Microneedles (MNs) are minimally invasive devices used to promote intradermal drug delivery. Dissolving MNs contain drug-associated to polymer blends, dissolving after insertion into skin, allowing drug release. This study comprises development and characterization of a pyramidal model of dissolving MNs (500 μm) prepared with 5% wt/wt aminolevulinic acid and 20% wt/wt Gantrez AN-139 in aqueous blend. Protoporphyrin IX formation and distribution were evaluated in tumor mice model by using fluorescence widefield imaging, spectroscopy, and confocal microscopy. MNs demonstrated excellent mechanical resistance penetrating about 250 μm with minor size alteration in vitro, and fluorescence intensity was 5-times higher at 0.5 mm on average compared to cream in vivo (being 10 ± 5 a.u. for MNs and 2.4 ± 0.8 a.u. for cream). Dissolving MNs have overcome topical cream application, being extremely promising especially for thicker skin lesions treatment using PDT.     

Yellow Fever Outbreaks in Unvaccinated Populations,Brazil, 2008–2009

Due to the risk of severe vaccine-associated adverse events, yellow fever vaccination in Brazil is only recommended in areas considered at risk for disease. From September 2008 through June 2009, two outbreaks of yellow fever in previously unvaccinated populations resulted in 21 confirmed cases with 9 deaths (case-fatality, 43%) in the southern state of Rio Grande do Sul and 28 cases with 11 deaths (39%) in Sao Paulo state. Epizootic deaths of non-human primates were reported before and during the outbreak. Over 5.5 million doses of yellow fever vaccine were administered in the two most affected states. Vaccine-associated adverse events were associated with six deaths due to acute viscerotropic disease (0.8 deaths per million doses administered) and 45 cases of acute neurotropic disease (5.6 per million doses administered). Yellow fever vaccine recommendations were revised to include areas in Brazil previously not considered at risk for yellow fever.     

The indigenous question: winning and losing with Bolivarian socialism

This research shows a critical assessment on Venezuelan indigenous people in the context of Bolivarian government of President Hugo Chávez.