Should the convergence between the social and biological vulnerabilities of black communities and the COVID-19 pandemic be considered?

The context of the COVID-19 pandemic has highlighted the structural inequalities and vulnerabilities experienced by black communities in the world, and in Brazil it is no different. The data generated in Brazil demonstrate that Brazilian inequality is alarming. Underreporting, non-prioritization of data that consider the variable race and color, and social groups in social vulnerability, help the unequal instrumentalization of epidemiological surveillance; many deaths from the black population are not being accounted for.

Mutational mechanism for DAB1 (ATTTC) insertion in SCA37: ATTTT repeat lengthening and nucleotide substitution.

Dynamic mutations by microsatellite instability are the molecular basis of a growing number of neuromuscular and neurodegenerative diseases. Repetitive stretches in the human genome may drive pathogenicity, either by expansion above a given threshold, or by insertion of abnormal tracts in nonpathogenic polymorphic repetitive regions, as is the case in spinocerebellar ataxia type 37 (SCA37). We have recently established that this neurodegenerative disease is caused by an (ATTTC) insertion within an (ATTTT) in a noncoding region of DAB1.

A repeat-primed PCR assay for pentanucleotide repeat alleles in spinocerebellar ataxia type 37.

Spinocerebellar ataxia 37 (SCA37) is caused by an (ATTTC) insertion in a polymorphic ATTTT repeat in the non-coding region of DAB1. The non-pathogenic alleles have a configuration [(ATTTT)], whereas pathogenic alleles have a complex structure of [(ATTTT)(ATTTC)(ATTTT)]. Molecular diagnosis of SCA37 is laborious because about 7% of the pentanucleotide repeat alleles in DAB1 are larger than 30 units and, thus, fail to amplify with standard PCR conditions, resulting in apparently homoallelism or in complete lack of PCR amplification in several cases.

A Pentanucleotide ATTTC Repeat Insertion in the Non-coding Region of DAB1, Mapping to SCA37, Causes Spinocerebellar Ataxia.

Advances in human genetics in recent years have largely been driven by next-generation sequencing (NGS); however, the discovery of disease-related gene mutations has been biased toward the exome because the large and very repetitive regions that characterize the non-coding genome remain difficult to reach by that technology. For autosomal-dominant spinocerebellar ataxias (SCAs), 28 genes have been identified, but only five SCAs originate from non-coding mutations. Over half of SCA-affected families, however, remain without a genetic diagnosis.

Characterization of polymeric nanoparticles for intravenous delivery: Focus on stability.

The nano-bio interaction has been of increased focus in the past years but very limited results have been obtained for polymeric nanoparticles (NP). Not only is needed to broaden the results obtained with model NP towards other nano-materials used for clinical application but the colloidal stability of NP as a variable consequence of the formation of the protein corona has been significantly understated. The lack and heterogeneity of assays to study NP stability and represent the biological environment call for the standardization of assays to improve the representativeness and comparability of results.

Unstable repeat expansions in neurodegenerative diseases: nucleocytoplasmic transport emerges on the scene.

An astonishing number of neurological diseases result from expansion of unstable repetitive sequences causing alterations in key neuronal processes. Some are progressive late-onset conditions related to aging, such as the spinocerebellar ataxias. In several of these pathologies, the expanded repeat is transcribed, producing an expanded RNA repeat that causes neurodegeneration by a complex mechanism, comprising 3 main pathways.

HIV genotypes and primary drug resistance among HIV-seropositive blood donors in Brazil: role of infected blood donors as sentinel populations for molecular surveillance of HIV.

Background: There are few surveillance studies analyzing genotypes or primary (transmitted) drug resistance in HIV-infected blood donors in Brazil. The aim of this study was to characterize patterns of HIV genotypes and primary resistance among HIV-seropositive donors identified at 4 geographically dispersed blood centers in Brazil.

Methods: All HIV-infected donors who returned for counseling at the 4 REDS-II Hemocenters in Brazil from January 2007 to March 2011 were invited to participate in a case-control study involving a questionnaire on risk factors.

Spatial analysis of migrating Apis mellifera colonies in Salvador, Bahia, Brazil.

Beekeeping in Brazil is growing but also associated with an increase in the number of human and animal accidents involved. In particular, bees of the Apis mellifera species (Africanized bees) are known for their aggressive behaviour and frequent swarming activity due to their poor adaptation to the human environment. This study analyzed the spatial distribution of occurrences of migratory swarms of A.