Publications by authors named "Sidney E B Dos Santos"

Identifying mutations in cancer-associated genes to guide patient treatments is essential for precision medicine. Circulating tumor DNA (ctDNA) offers valuable insights for early cancer detection, treatment assessment, and surveillance. However, a key issue in ctDNA analysis from the bloodstream is the choice of a technique with adequate sensitivity to identify low frequent molecular changes.

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COVID-19 is a systemic disease caused by the etiologic agent SARS-CoV-2, first reported in Hubei Province in Wuhan, China, in late 2019. The SARS-CoV-2 virus has evolved over time with distinct transmissibility subvariants from ancestral lineages. The clinical manifestations of the disease vary according to their severity and can range from asymptomatic to severe.

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  • Radiotherapy can negatively impact healthy tissues, leading to toxicities potentially linked to genetic factors.
  • Radiogenomics aims to tailor radiotherapy treatments by examining genetic profiles, particularly in under-researched populations like indigenous Amazonians.
  • The study identified 39 genetic variants in the indigenous population, including some potentially protective against treatment side effects, highlighting the need for personalized radiotherapy approaches.
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Background: Acute Lymphoblastic Leukemia (ALL) is a neoplasm of the hematopoietic system characterized by a clonal expansion of abnormal lymphocyte precursor cells. ALL is the most common form of cancer in children, but despite advances in treatment, it can still be fatal. Ethnic differences influence survival rates, and genomic ancestry plays an important role, especially in mixed-race populations such as Latin America.

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  • * The research focused on the genomic profile of 64 Indigenous individuals, identifying high-impact genetic variants that suggest greater susceptibility to mercury exposure compared to global populations.
  • * As the first study of its kind, the findings aim to inform public policies by identifying at-risk populations through genomic analysis related to mercury metabolism.
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Breast cancer (BCa) is the most common cancer and leading cause of cancer death among women globally. This can be explained by the genetic factor of this disease. This article aims to correlate the epidemiological data, worldwide incidence, and mortality of BCa with the Single-Nucleotide Polymorphisms (SNPs) associated with the susceptibility and severity in different populations.

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Leprosy is an infectious disease primarily caused by the obligate intracellular parasite . Although it has been considered eradicated in many countries, leprosy continues to be a health issue in developing nations. Besides the social stigma associated with it, individuals affected by leprosy may experience nerve damage leading to physical disabilities if the disease is not properly treated or early diagnosed.

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  • Acute lymphoblastic leukemia (ALL) is the most common cancer in children, and certain genetic variants (SNVs) may influence how patients respond to treatment and experience side effects.
  • The study focused on 25 specific SNVs in genes related to microRNA in 77 patients from the Brazilian Amazon, utilizing the TaqMan OpenArray™ Genotyping System for analysis.
  • Results indicated some SNVs increased the risk of neurological and gastrointestinal toxicities, while others provided protection, highlighting the potential to use these genetic markers to better understand and manage treatment-related toxicities in ALL patients.
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Non-small cell lung cancer (NSCLC) accounts for the vast majority of cases of lung neoplasms. It is formed in multiple stages, with interactions between environmental risk factors and individual genetic susceptibility and with genes involved in the immune and inflammatory response paths, cell or genome stability, and metabolism, among others. Our objective was to evaluate the association between five genetic variants (, , , and ) and the development of NSCLC in the Brazilian Amazon.

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Gastric cancer (GC) is a multifactorial, complex, and aggressive disease with a prevalence of one million new cases and high global mortality. Factors such as genetic, epigenetic, and environmental changes contribute to the onset and progression of the disease. Identification of INDELs in miRNA and its target sites in current studies showed an important role in the development of cancer.

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Due to their continuing geographic isolation, the Amerindian populations of the Brazilian Amazon present a different genetic profile when compared to other continental populations. Few studies have investigated genetic variants present in these populations, especially in the context of next-generation sequencing. Knowledge of the molecular profile of a population is one of the bases for inferences about human evolutionary history, in addition, it has the ability to assist in the validation of molecular biomarkers of susceptibility to complex and rare diseases, and in the improvement of specific precision medicine protocols applied to these populations and to populations with high Amerindian ancestry, such as Brazilians.

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Hereditary gastric cancers (HGCs) are supposed to be rare and difficult to identify. Nonetheless, many cases of young patients with gastric cancer (GC) fulfill the clinical criteria for considering this diagnosis but do not present the defined pathogenic mutations necessary to meet a formal diagnosis of HGC. Moreover, GC in young people is a challenging medical situation due to the usual aggressiveness of such cases and the potential risk for their relatives when related to a germline variant.

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The COVID-19 pandemic initiated a race to determine the best measures to control the disease and to save as many people as possible. Efforts to implement social distancing, the use of masks, and massive vaccination programs turned out to be essential in reducing the devastating effects of the pandemic. Nevertheless, the high mutation rates of SARS-CoV-2 challenge the vaccination strategy and maintain the threat of new outbreaks due to the risk of infection surges and even lethal variations able to resist the effects of vaccines and upset the balance.

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Leprosy is a chronic neurodermatological disease caused by the bacillus . Recent studies show that SNPs in genes related to miRNAs have been associated with several diseases in different populations. This study aimed to evaluate the association of twenty-five SNPs in genes encoding miRNAs related to biological processes and immune response with susceptibility to leprosy and its polar forms paucibacillary and multibacillary in the Brazilian Amazon.

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A number of genomic variants related to native American ancestry may be associated with an increased risk of developing Acute Lymphoblastic Leukemia (ALL), which means that Latin American and hispanic populations from the New World may be relatively susceptible to this disease. However, there has not yet been any comprehensive investigation of the variants associated with susceptibility to ALL in traditional Amerindian populations from Brazilian Amazonia. We investigated the exomes of the 18 principal genes associated with susceptibility to ALL in samples of 64 Amerindians from this region, including cancer-free individuals and patients with ALL.

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Prostate cancer (PCa) incidence and mortality vary across territories and populations. This can be explained by the genetic factor of this disease. This article aims to correlate the epidemiological data, worldwide incidence, and mortality of PCa with single-nucleotide polymorphisms (SNPs) associated with the susceptibility and severity of this neoplasm in different populations.

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Background: Tuberculosis (TB) is an infectious disease caused by the bacterium and represents an important global public health issue. Single-nucleotide polymorphisms and INDELs are common genetic variations that can be located in genes associated with immune response and, therefore, they may have direct implications over the phenotype of susceptibility to infections like tuberculosis. This study aimed to investigate the association between the 17 genetic polymorphisms and susceptibility to tuberculosis in a Brazilian population.

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In Brazil, Acute lymphoid leukemia (ALL) is the leading cause of cancer deaths in children and adolescents. Treatment toxicity is one of the reasons for stopping chemotherapy. Amerindian genomic ancestry is an important factor for this event due to fluctuations in frequencies of genetic variants, as in the and genes, which make up the pharmacokinetic and pharmacodynamic pathways of chemotherapy.

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Genetic factors associated with COVID-19 disease outcomes are poorly understood. This study aimed to associate genetic variants in the , , , , , , and genes with the risk of severe forms of COVID-19 in Amazonian Native Americans, and to compare the frequencies with continental populations. The study population was composed of 64 Amerindians from the Amazon region of northern Brazil.

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Genetic variations in have been associated with different pathologies in global literature, but there are no data regarding this gene in Native American populations. The Amazonian Native American populations have lower genetic diversity and are more different from other continental groups. We investigated 18 genetic variants in the gene in Amazonian indigenous and compared our results with the ones found in global populations, which were publicly available in the 1000 Genomes Project, gnmAD and ABraOM databases.

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Lung cancer is one of the most frequent neoplasms in the world. Because it is a complex disease, its formation occurs in several stages, stemming from interactions between environmental risk factors, such as smoking, and individual genetic susceptibility. Our objective was to investigate associations between a gene polymorphism (rs8175347) and lung cancer risk in an Amazonian population.

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Article Synopsis
  • Tuberculosis (TB) is a serious infection caused by the bacterium Mycobacterium tuberculosis (Mtb), with significant health risks linked to genetic differences in individuals.
  • This study focused on examining 26 specific genetic variants (SNPs) to see if they influence the likelihood of developing TB in the Amazon population, involving 178 participants.
  • Findings revealed that certain SNPs are linked to both increased and decreased risks of TB, suggesting a genetic component to how individuals might respond to this infection and potentially aiding in future diagnostic advancements.
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Autism spectrum disorder is a neurodevelopmental disorder, affecting one in 160 children worldwide. The causes of autism are still poorly understood, but research shows the relevance of genetic factors in its pathophysiology, including the , , and genes. Information about the genetic influence on various diseases, including autism, in the Amerindian population from Amazon, is still scarce.

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Background: Sarcopenia is a disease characterized by progressive reduction in muscle mass and strength or function. Although it is known that sarcopenia may be associated with environmental factors, studies suggest the identification of genes related to skeletal muscle maintenance that explain the susceptibility to the disease.

Objective: To analyze the influence of gene polymorphism on susceptibility to sarcopenia in the elderly.

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  • Fluoropyrimidines are commonly used cancer drugs but have significant toxicity, and this study examined genetic variations in patients treated with these drugs in the Brazilian Amazon.
  • The research involved 216 patients with gastrointestinal cancers, analyzing 33 gene polymorphisms and using advanced genotyping technology to assess ancestry and potential toxicity risks.
  • Four specific genetic polymorphisms (in the ABCC4, FPGS, SLC29A1, and MTHFR genes) were identified as significant predictors of toxicity, highlighting the importance of personalized medicine in this unique population.
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