Mayara Calixto da Silva

Prof. Mayara Calixto da Silva

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2020 in Revista Brasileira de Saúde Materno Infantil
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JCJéssica Vilarinho Cardoso
Jéssica Vilarinho Cardoso
DMDaniel Machado
Daniel Machado
MSMayara Calixto da Silva
Mayara Calixto da Silva
PBPlínio Tostes Berardo
Plínio Tostes Berardo
RFRenato Ferrari
Renato Ferrari
Jamila PeriniJamila Perini
Jamila Perini
Objectives: to describe the epidemiological and clinical profile of women with endometriosis and to determine the association with the prognostic characteristics of the disease. Methods: retrospective descriptive study involving 237 women attended at two referral hospitals for endometriosis, between 2011 and 2017. Associations between groups were estimated using logistic regression models. Results: most women (65.4%) were of reproductive age (29-39 years), with a body mass index in the range of 18.5-24.9 kg/m2 and a high prevalence (23-81%) of symptoms of the disease, with 49.5% being infertile. The average time of diagnosis was 5 years. Ovarian endometrioma and/or deep infiltrative endometriosis (DIE) were the most frequent type of endometriosis (87%), and 59% of patients were in the III/IV stage of the disease. Approximately 87% of women with surgical diagnosis were aged over 30, married (70%) and had lower parity. Dyspareunia was negatively associated with superficial endometriosis. Infertility was positively associated with age (30-39 years) and DIE in the uterine tubes; dysmenorrhea with DIE in the uterosacral ligament; cyclic intestinal complaints with DIE in the rectosigmoid and intestine, and with DIE classification and III/IVstage. Conclusions: knowing the epidemiological and clinical profile of Brazilian women with endometriosis can help in diagnosis and treatment planning.

21 June 2022 in Journal of Infection and Public Health
Verified
Journal Article
Open access
VSVanessa da Costa Sousa
Vanessa da Costa Sousa
MSMayara Calixto da Silva
Mayara Calixto da Silva
MMMatheus Pereira de Mello
Matheus Pereira de Mello
JGJoão Antonio Matheus Guimaraes
João Antonio Matheus Guimaraes
Jamila PeriniJamila Perini
Jamila Perini
During the pandemic of COVID-19, phylogenetic changes have been observed in the characteristics of the virus, in the diagnosis and treatment of the disease. The clinical course and the severe form of the disease depends on several factors. This study characterized the beginning setting for patient care of COVID-19 in a referral center in one of the main capital cities of Brazil. In addition, were evaluated the factors associated with mortality, length of stay, and diagnostic outcome. A cross-sectional study was conducted during May 2020 (n = 1100). The association of the variables with outcome was evaluated by a multivariable logistic regression model, using odds ratios (OR) and 95 % confidence intervals (CI). Overall, 76 % of patients were COVID-19 positive, and 70 % were diagnosed by RT–qPCR. The majority were male (56 %), and over 52 years old (74 %), 68 % had hypertension, 44 % had diabetes mellitus, and 32 % were obese. The mean length of stay was 10 ± 8 days, which was higher in the 34 % who died (≥14; OR=2; 95 %CI=1.4–4) and who had hypertension (OR=2; 95 %CI=1.3–3) (P < 0.001). The mean length of stay was also higher (P = 0.008) for those patients with pulmonary impairment ≥ 50 % (10.72 ± 8.24), than those with< 50 % (8.98 ± 6.81). Age (>62 and 65 years) was associated with longer hospitalization (OR=2; 95 %CI=1.4–3) and death (OR=6; 95 %CI=3–11). The time of sample collection for RT–qPCR was different between positive and negative tests (P = 0.001), with the time of 4–10 days showing a greater chance for virus detection (OR=2.9; 95 %CI=1.6–5). Death was associated with age and pulmonary impairment. The length of hospitalization was associated with age, hypertension, pulmonary impairment and death. The time of sample collection to perform RT–qPCR and the rapid test was associated with a positive result for COVID-19. These results highlight the ongoing challenge of diagnosing, treating, and mitigating the effects caused by the COVID-19 pandemic.

Jamila PeriniJamila Perini
Jamila Perini
MSMayara Calixto da Silva
Mayara Calixto da Silva
Ana Claudia VasconcellosAna Claudia Vasconcellos
Ana Claudia Vasconcellos
PVPaulo Victor Sousa Viana
Paulo Victor Sousa Viana
MLMarcelo de Oliveira Lima
Marcelo de Oliveira Lima
Paulo BastaPaulo Basta
Paulo Basta
Genetic polymorphisms involved in mercury toxicokinetics and toxicodynamics may be associated with severe mercury toxicity. This study aimed to investigate the impact of an ALAD polymorphism on chronic mercury exposure and the health situation of indigenous children from the Brazilian Amazon. One-hundred-and-three indigenous children (under 15 years old) were included and genotyped (rs1800435) using a TaqMan validated assay. The mean age was 6.6 ± 4.5 years old, 60% were female, 49% presented with anemia, and the mean hair mercury concentration was 7.0 ± 4.5 (1.4–23.9) µg/g, with 49% exceeding the reference limit (≥6.0 µg/g). Only two children were heterozygous ALAD, while the others were all wild type. Minor allele frequency (ALAD G) and heterozygous genotype (ALAD CG) were 1% and 2%, respectively. The two children (12 and 14 years old) with the ALAD polymorphism had mercury levels above the average as well as had neurological symptoms related to chronic mercury exposure, such as visual field alterations, memory deficit, distal neuropathy, and toe amyotrophy. Both children also reported frequent consumption of fish in the diet, at least three times a week. In conclusion, our data confirm that an ALAD polymorphism can contribute to mercury half-life time, harmful effects, and neuropsychological disorders in indigenous children with chronic mercury exposure to gold mining activity.

31 January 2023 in Toxics
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MSMayara Calixto da Silva
Mayara Calixto da Silva
Rogério Adas Ayres de OliveiraRogério Adas Ayres de Oliveira
Rogério Adas Ayres de Oliveira
Ana Claudia VasconcellosAna Claudia Vasconcellos
Ana Claudia Vasconcellos
BRBruno Hojo Reboucas
Bruno Hojo Reboucas
BPBruna Duarte Pinto
Bruna Duarte Pinto
Jamila PeriniJamila Perini
Jamila Perini
Genetic polymorphisms may be involved with mercury levels and signs and symptoms of intoxication from this exposure. Therefore, the aims were to describe the frequency of the GSTP1 polymorphism and to evaluate its effects on mercury levels and neurological signs in three Munduruku indigenous villages in the Brazilian Amazon. One-hundred-and-seven indigenous (over 12 years old) were included and genotyped (rs1695) using a TaqMan validated assay. Then, associations were evaluated by binary logistic regression, using odds ratios (OR) and 95% confidence intervals (CI). Mean age was 27.4 ± 13.9 years old, 52.3% were male, mean hair mercury concentration was 8.5 ± 4.3, exceeding the reference limit (≥6.0 µg/g), and were different among the three villages: 13.5 ± 4.6 µg/g in Sawré Aboy, 7.4 ± 2.3 µg/g in Poxo Muybu and 6.9 ± 3.5 µg/g in Sawré Muybu. The minor allele frequency of GSTP1 G was significantly different among the villages: 57% Sawré Muybu, 21% Poxo Muybu and 15% Sawré Aboy. Finally, after adjustment, GSTP1 GG and GA genotypes were associated with lower levels of Hg (OR = 0.13; CI95% = 0.03–0.49) and abnormal somatosensory signs (OR = 3.7; 95%IC = 1.5–9.3), respectively. In conclusion, monitoring this population is imperative to identify individuals at higher risk of developing signs of chronic mercury exposure based on the genetic profile.

1 March 2024 in Toxics
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Journal Article
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AJAdriana Duringer Jacques
Adriana Duringer Jacques
Mirian Akiko Furutani de OliveiraMirian Akiko Furutani de Oliveira
Mirian Akiko Furutani de Oliveira
MSMayara Calixto da Silva
Mayara Calixto da Silva
CHCristina Hofer
Cristina Hofer
Paulo BastaPaulo Basta
Paulo Basta
Despite legal safeguards, the Yanomami community faces challenges such as unauthorized incursions by gold miners, resulting in environmental degradation, particularly from mercury. This jeopardizes the health and food security of indigenous individuals, especially due to the consumption of contaminated fish. Ethnic and racial disparities persist in indigenous healthcare, marked by troubling health indicators such as malnutrition, anemia, and infectious diseases. This cross-sectional study, conducted in October 2022 in the Yanomami Indigenous Territory in the Amazon Forest, Brazil, presented clinical, laboratory, and neurodevelopmental findings in Yanomami children chronically exposed to methylmercury. The results revealed that Yanomami children exhibited weights and heights below expectations (median Z-scores of −1.855 for weight for age and −2.7 for height for age), a high prevalence of anemia (25%), low vaccination coverage (15%), and low IQ (average 68.6). The Total Hair Mercury (Total Hg) levels ranged from 0.16 µg/g to 10.20 µg/g (mean: 3.30 µg/g; median: 3.70 µg/g). Of 117 children tested, 93 children (79.4%) had levels ≥ 2.0 µg/g (had no significant difference between sex). Among the 58 children for whom it was possible to estimate the Total Intelligence Quotient (TIQ), the average value was 68.6, ranging from 42 to 92 points (median: 69.5; standard deviation: 10.5). Additionally, the lowest score on the IQ test was associated with 5 times the risk of having high levels of mercury in their hair, 2,5 fold the risk of having an older age, and almost 8 times the risk of consuming fish, adjusting for nut consumption. Notwithstanding the study’s limitations, results suggest that mercury contamination from illegal mining activities on indigenous lands may negatively impact neurodevelopment in older indigenous children, particularly those fish consumers, despite the inherent benefits of fish consumption. Addressing other socio-environmental concerns is crucial for enhancing the overall health of the population.

14 June 2017 in Revista Brasileira de Ginecologia e Obstetrícia
Verified
Journal Article
Open access
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JCJéssica Vilarinho Cardoso
Jéssica Vilarinho Cardoso
DMDaniel Machado
Daniel Machado
RFRenato Ferrari
Renato Ferrari
MSMayara Calixto da Silva
Mayara Calixto da Silva
PBPlínio Tostes Berardo
Plínio Tostes Berardo
Jamila PeriniJamila Perini
Jamila Perini
Purpose To evaluate the magnitude of the association of the polymorphisms of the genes PGR, CYP17A1 and CYP19A1 in the development of endometriosis. Methods This is a retrospective case-control study involving 161 women with endometriosis (cases) and 179 controls. The polymorphisms were genotyped by real-time polymerase chain reaction using the TaqMan system. The association of the polymorphisms with endometriosis was evaluated using the multivariate logistic regression. Results The endometriosis patients were significantly younger than the controls (36.0 ± 7.3 versus 38.0 ± 8.5 respectively, p = 0.023), and they had a lower body mass index (26.3 ± 4.8 versus 27.9 ± 5.7 respectively, p = 0.006), higher average duration of the menstrual flow (7.4 ± 4.9 versus 6.1 ± 4.4 days respectively, p = 0.03), and lower average time intervals between menstrual periods (25.2 ± 9.6 versus 27.5 ± 11.1 days respectively, p = 0.05). A higher prevalence of symptoms of dysmenorrhea, dyspareunia, chronic pelvic pain, infertility and intestinal or urinary changes was observed in the case group when compared with the control group. The interval between the onset of symptoms and the definitive diagnosis of endometriosis was 5.2 ± 6.9 years. When comparing both groups, significant differences were not observed in the allelic and genotypic frequencies of the polymorphisms PGR +331C > T, CYP17A1 -34A > G and CYP19A1 1531G > A, even when considering the symptoms, classification and stage of the endometriosis. The combined genotype PGR +331TT/CYP17A1 -34AA/CYP19A11531AA is positively associated with endometriosis (odds ratio [OR] = 1.72; 95% confidence interval [95%CI] = 1.09–2.72). Conclusions The combined analysis of the polymorphisms PGR-CYP17A1-CYP19A1 suggests a gene-gene interaction in the susceptibility to endometriosis. These results may contribute to the identification of biomarkers for the diagnosis and/or prognosis of the disease and of possible molecular targets for individualized treatments.