miRNAs in cerebrospinal fluid associated with Alzheimer's disease: A systematic review and pathway analysis using a data mining and machine learning approach.

Alzheimer's disease (AD) is the most common type and accounts for 60%-70% of the reported cases of dementia. MicroRNAs (miRNAs) are small non-coding RNAs that play a crucial role in gene expression regulation. Although the diagnosis of AD is primarily clinical, several miRNAs have been associated with AD and considered as potential markers for diagnosis and progression of AD. We sought to match AD-related miRNAs in cerebrospinal fluid (CSF) found in the GeoDataSets, evaluated by machine learning, with miRNAs listed in a systematic review, and a pathway analysis. Using machine learning approaches, we identified most differentially expressed miRNAs in Gene Expression Omnibus (GEO), which were validated by the systematic review, using the acronym PECO-Population (P): Patients with AD, Exposure (E): expression of miRNAs, Comparison (C): Healthy individuals, and Objective (O): miRNAs differentially expressed in CSF. Additionally, pathway enrichment analysis was performed to identify the main pathways involving at least four miRNAs selected. Four miRNAs were identified for differentiating between patients with and without AD in machine learning combined to systematic review, and followed the pathways analysis: miRNA-30a-3p, miRNA-193a-5p, miRNA-143-3p, miRNA-145-5p. The pathways epidermal growth factor, MAPK, TGF-beta and ATM-dependent DNA damage response, were regulated by these miRNAs, but only the MAPK pathway presented higher relevance after a randomic pathway analysis. These findings have the potential to assist in the development of diagnostic tests for AD using miRNAs as biomarkers, as well as provide understanding of the relationship between different pathophysiological mechanisms of AD.

microRNA miR-133a as a Biomarker for Doxorubicin-Induced Cardiotoxicity in Women with Breast Cancer: A Signaling Pathway Investigation.

Cardiovascular toxicity is the main adverse effect of Doxorubicin (DOX) in cancer patients. microRNAs (miRNAs) are promising biomarkers to identify cardiac injury induced by DOX in breast cancer patients during the subclinical phase. Using RT-qPCR, we compared the expression of circulating miR-208a5p, miR-133a, miR-499a5p, miR-15a, miR-133b, and miR-49a3p in serum samples from DOX-induced cardiotoxicity (case) compared to the non-cardiotoxicity group (control). To further explore the potential roles of these circulating miRNA in cardiotoxicity, we searched the miRTarBase for experimentally validated miRNA-target interactions and performed a functional enrichment analysis based on those interactions. miR-133a was significantly upregulated in case compared to control group. The most relevant pathway regulated by miR-133a was ErbB2 signaling, whose main genes involved are EGFR, ERBB2, and RHOA, which are possibly downregulated by miR133a. The other miRNAs did not show significant differential expression when compared on both groups. The data suggest that miR-133a is associated with DOX-based cardiotoxicity during chemotherapy in breast cancer patients through ErbB2 signaling pathway. Moreover, miR-133a may be a future marker of DOX-induced cardiotoxicity in women with breast cancer.

Interleukin-10 Levels are Associated with Doxorubicin-Related Cardiotoxicity in Breast Cancer Patients in a One-Year Follow-Up Study.

BACKGROUND: Myocardial toxicity is a common side effect of doxorubicin (DOXO) therapy in breast cancer patients. We hypothesized that DOXO-induced cardiotoxicity may be related to the release of inflammatory cytokines in response to the treatment. This study aimed to assess changes in plasma levels of interleukin (IL)-1ß, IL-6, IL-10 and tumor necrosis factor (TNF) after chemotherapy and to correlate these levels with cardiac biomarkers and clinical data. METHODS: Sixty-four patients with breast cancer treated with DOXO were included. Twenty-two subjects (cases) developed cardiotoxicity until one year after the end of DOXO treatment. Cytokines and cardiac markers were evaluated before starting chemotherapy (T0), up to 7 days after the last infusion (T1) and 12 months after the last infusion (T2). RESULTS: Higher IL-10 levels were observed in the case group compared to controls at T1 (p = .006) and T2 (p = .046). The IL-1ß, IL-6 and TNF levels did not change during treatment in each group (p > .05), nor between the case and control groups. The IL-10 levels were higher at T1 than at T0 and T2 (p < .05 for both) in the cardiotoxicity group. A correlation between IL-10 and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels at T0 and T2 in the cardiotoxicity group was observed (p = .048 and p = .004, respectively). CONCLUSION: Our study demonstrated that DOXO induced an increase in plasma IL-10 levels in patients who presented cardiotoxicity after treatment, which correlated with NT-proBNP levels.

The Role of the Mediterranean Dietary Pattern on Metabolic Control of Patients with Diabetes Mellitus: A Narrative Review.

Diabetes mellitus (DM) is a metabolic disorder characterised by hyperglycemia and abnormalities in carbohydrate, fat and protein metabolism. Several studies demonstrated that foods typical of the Mediterranean diet (MedDiet), including vegetables, fruits, oilseeds, extra virgin olive oil and fish, can promote health benefits for individuals at risk of or with type 2 diabetes (T2DM). In this review, we summarised randomised clinical trials, cohort studies, meta-analyses and systematic reviews that evaluated the effects of the MedDiet on metabolic control of T2DM. The data suggest that the MedDiet influences cardiovascular risk factors, including blood pressure, lipid profile, insulin resistance, inflammation and glucose metabolism, in T2DM patients. In conclusion, the MedDiet appears to protect patients from macro- and microangiopathy and should be considering in the management of diabetic patients.

Identification of Clinical and Laboratory Variables Associated with Cardiotoxicity Events Due to Doxorubicin in Breast Cancer Patients: A 1-Year Follow-Up Study.

Cardiovascular adverse events in patients with breast cancer undergoing chemotherapy (CT) are frequent due to the high cardiotoxic potential of treatments, especially doxorubicin (DOXO). This study aimed to evaluate the association of plasma levels of various biomarkers with cardiotoxicity in women with breast cancer on DOXO-based chemotherapy. In this single center prospective cohort, 80 breast cancer patients who used DOXO as a first-line treatment for cancer were evaluated. Patients were assessed at three time points: before CT (T0), 1 week after (T1) and 12 months after DOXO treatment (T2). The predominant histological classification was ductal carcinoma, n = 72 (90.0%); the most frequent molecular classification was Human epidermal growth factor receptor-type 2 positive (HER2+), n = 34 (43.0%). In patients submitted to complementary treatment with trastuzumab (n = 23), there was no association with cardio-specific biomarkers. Evaluating the clinical variables and the laboratory parameters in T1 and T2 in relation to T0, the reduction any time of N-terminal-pro hormone B-type natriuretic peptide (NT-proBNP), triglycerides and hematocrit levels showed an association with higher cardiotoxicity risk. In addition, increased levels of troponin I (cTnI) and glycated hemoglobin (HbA1c) showed an independent association with the occurrence of cardiotoxicity. These results suggest that the evaluation of these laboratory tests should be included routinely to identify breast cancer patients under DOXO treatment at cardiotoxicity risk.

microRNAs associated to anthracycline-induced cardiotoxicity in women with breast cancer: A systematic review and pathway analysis.

BACKGROUND: Cardiotoxicity is a common and serious adverse effect of anthracycline therapy in breast cancer patients. The current criteria for cardiotoxicity are based on imaging and cardiac biomarkers. However, there is a need for new biomarkers to help with early diagnosis. MicroRNAs (miRNAs) are small non-coding RNA molecules that play an important role in the regulation of gene expression. Several miRNAs have been associated with cardiovascular diseases and are biomarkers under investigation for cancer treatment-related cardiotoxicity. METHODS: We performed a systematic literature search of Medline/PubMed, Cochrane Central Register of Controlled Trials, Scopus, Lilacs, Web of Science and Embase, until April 2020. Cohort studies that reported miRNA biomarkers in breast cancer patients with anthracycline-induced cardiotoxicity and non-cardiotoxicity patients were included. Moreover, we searched the miRTarBase for experimentally validated miRNA-target interactions. RESULTS: Among the 209 studies retrieved, five fulfilled the inclusion criteria. Let-7f, miR-1, miR-20a, miR-126 and miR-210 were validated in two population-based cohorts. The pro-angiogenic miRNAs let-7f, miR-20a, miR-126 and miR-210 were significantly down-regulated in epirubicin-cardiotoxicity when compared to the non-cardiotoxicity group. miR-1 has been shown to provide diagnostic and prognostic information in the setting of myocardial infarction, but changes in its levels are controversial in doxorubicin-treated breast cancer patients with cardiotoxicity. Reactome pathways relevant to cardiotoxicity were found from the target genes for let-7f, miR-1, miR-20a, miR-126 and miR-210 at miRTarBase. CONCLUSION: The data suggest that let-7f, miR-1, miR-20a, miR-126 and miR-210 are associated with anthracycline-based cardiotoxicity during chemotherapy in breast cancer patients.

The dual effect of C-peptide on cellular activation and atherosclerosis: Protective or not?

C-peptide is a cleavage product of proinsulin that acts on different type of cells, such as blood and endothelial cells. C-peptide biological effects may be different in type 1 and type 2 diabetes. Besides, there are further evidence for a functional interaction between C-peptide and insulin. In this way, C-peptide has ambiguous effects, acting as an antithrombotic or thrombotic molecule, depending on the physiological environment and disease conditions. Moreover, C-peptide regulates interaction of leucocytes, erythrocytes, and platelets with the endothelium. The beneficial effects include stimulation of nitric oxide production with its subsequent release by platelets and endothelium, the interaction with erythrocytes leading to the generation of adenosine triphosphate, and inhibition of atherogenic cytokine release. The undesirable action of C-peptide includes the chemotaxis of monocytes, lymphocytes, and smooth muscle cells. Also, C-peptide was related with increased lipid deposits and elevated smooth muscle cells proliferation in the vessel wall, contributing to atherosclerosis. Purpose of this review is to explore these dual roles of C-peptide on the blood, contributing at one side to haemostasis and the other to atherosclerotic process.

Duffy blood group system: New genotyping method and distribution in a Brazilian extra-Amazonian population.

Duffy blood group system is of interest in several fields of science including transfusion medicine, immunology and malariology. Although some methods have been developed for Duffy polymorphism genotyping, not all of them have been sufficiently described and validated, and all present limitations. At the same time, the frequency of Duffy alleles and antigens in some densely populated regions of the world are still missing. In this study we present new tests for genotyping the major alleles of the Duffy blood system and describe Duffy alleles and antigens in blood donors and transfusion-dependent patients in Minas Gerais, Brazil. A simple and reproducible strategy was devised for Duffy genotyping based on real-time PCR that included SNPs rs12075 and rs2814778. No significant differences between the allele frequencies were observed comparing blood donors and patients. Among the blood donors, the phenotype Fy(a-b+) was the most common and the Fy(a-b-) phenotype, associated with populations of African descent, was remarkably less common among subjects who self-identified as black in comparison to other ethnoracial categories. However, the African ancestry estimated by molecular markers was significantly higher in individuals with the allele associated to the Duffy null phenotype. The genotyping method presented may be useful to study Duffy genotypes accurately in different contexts and populations. The results suggest a reduced risk of alloimmunization for Duffy antigens and increased susceptibility for malaria in Minas Gerais, considering the high frequency of Duffy-positive individuals.

Vitamin D receptor polymorphisms and the polycystic ovary syndrome: A systematic review.

Polycystic ovary syndrome (PCOS) is the most frequent endocrinological disorder that affects women of reproductive age, leading to metabolic alterations, such as hyperandrogenism, obesity, menstrual irregularities, insulin resistance, and polycystic ovaries. The etiology remains unclear, but several genetic and environmental factors have been correlated with manifestations of this syndrome. Vitamin D plays important roles in metabolic pathways affected by PCOS, including calcium homeostasis, the insulin pathway, and sex hormone synthesis. Vitamin D concentration has been related with the severity of this disorder, and vitamin D receptor polymorphisms have been shown in some studies to have an association with some of the patterns presented by PCOS. The objective of this study is to provide an up-to-date review about vitamin D receptor polymorphisms and their association with PCOS.

Resistance of dialyzed patients to erythropoietin.

Resistance to recombinant human erythropoietin is a common condition in dialyzed patients with chronic kidney disease and is associated with more hospitalizations, increased mortality and frequent blood transfusions. The main cause of hyporesponsiveness to recombinant human erythropoietin in these patients is iron deficiency. However, a high proportion of patients does not respond to treatment, even to the use of intravenous iron, which indicates the presence of other important causes of resistance. In addition to the iron deficiency, the most common causes of resistance include inflammation, infection, malnutrition, inadequate dialysis, and hyperparathyroidism, although other factors may be associated. In the presence of adequate iron stores, other causes should be investigated and treated appropriately.

Resistance of dialyzed patients to erythropoietin

Resistance to recombinant human erythropoietin is a common condition in dialyzed patients with chronic kidney disease and is associated with more hospitalizations, increased mortality and frequent blood transfusions. The main cause of hyporesponsiveness to recombinant human erythropoietin in these patients is iron deficiency. However, a high proportion of patients does not respond to treatment, even to the use of intravenous iron, which indicates the presence of other important causes of resistance. In addition to the iron deficiency, the most common causes of resistance include inflammation, infection, malnutrition, inadequate dialysis, and hyperparathyroidism, although other factors may be associated. In the presence of adequate iron stores, other causes should be investigated and treated appropriately.

Alfa-Talassemias: aspectos moleculares e diagnóstico / Alpha-Thalassemias: molecular aspects and diagnosis

A α-talassemia é um dos distúrbios da síntese de hemoglobina mais comuns no mundo, sendo causada, principalmente,por mutações delecionais nos genes α-globínicos. De acordo com o número degenes mutados que varia de um a quatro, a α-talassemia pode ser divididaem quatro fenótipos: α-talassemia silenciosa, traço α-talassêmico, Doençade HbH e hidropsia fetal, espectivamente. Segundo a literatura, afrequência de α-talassemia no Brasil também é considerável, sendo de grande importância o diagnósticocorreto deste distúrbio, que pode ser realizado com auxílio de exames convencionais que apresentam vantagens e desvantagens. Contudo, em alguns casos, principalmente nas formas menores da α-talassemia, a confirmação diagnóstica só pode ser realizada através dos exames moleculares que, apesar de confirmatórios, não estão disponíveisem grande parte dos laboratórios de análises clínicas e, devido ao custo, não são acessíveis à população em geral..

Parvovirus B19 (B19) and cytomegalovirus (CMV) infections and anti-erythropoietin (anti-EPO) antibodies in patients on dialysis hyporesponsive to erythropoietin therapy.

BACKGROUND: Approximately 10% of patients receiving recombinant human erythropoietin (rHuEPO) do not respond to the treatment. We evaluated parvovirus B19 (B19) and cytomegalovirus (CMV) infections and antierythropoietin (anti-EPO) antibodies as potential causes of anemia in dialyzed patients, hyporesponsive to rHuEPO. METHODS: Data from 120 dialyzed patients, receiving rHuEPO alfa, were collected: demographic characteristics, rHuEPO dose, duration of rHuEPO treatment and time on dialysis, etiology of chronic kidney disease and transfusion history. Serology and PCR were performed to address B19 and CMV infection status. An ELISA was developed to detect anti-EPO antibodies. RESULTS: rHuEPO resistance correlated with high ferritin levels (p = 0.001) and short time on dialysis (p = 0.012). B19 DNA was found in 10 (8.3%) dialyzed patients and CMV DNA was detected in 33 (27.5%). There was no significant correlation between B19 infection and anemia,while a tendency of correlation between active CMV infection and hemoglobin levels or hematocrit value (p= 0.069 and p= 0.070, respectively) has been observed. Anti-EPO antibodies were not detected in any patient. CONCLUSIONS: B19 infection is a rare complication in dialyzed patients and should be investigated after exclusion of other common causes, while CMV infection is rather common. The role of CMV infection in the hyporesponsiveness in dialyzed patients should be further evaluated in other studies. Our data suggest that anti-EPO antibodies are not involved in rHuEPO resistance in this population.

Human parvovirus B19 infection in a renal transplant recipient: a case report.

BACKGROUND: Parvovirus B19 presents tropism for human erythroid progenitor cells, causing chronic anemia in organ transplant recipients, due to their suppressed humoral and cellular responses. Diagnosis may be achieved through serological tests for detection of anti-B19 antibodies. However, renal transplant recipients are not routinely tested for parvovirus B19 infection, since there is scanty data or consensus on screening for B19 infection, as well as for treatment or preventive management of transplanted patients. CASE PRESENTATION: Herein we report a kidney transplant recipient, who was unresponsive to treatment of severe anemia, and presented hypocellular hematopoietic marrow, megaloblastosis and hypoplasia of erythroid lineage with larger cells with clear nuclei chromatin and eosinophilic nuclear inclusions. This patient was seropositive for Epstein-Barr and Cytomegalovirus infections and negative for anti-parvovirus B19 IgM and IgG antibodies, although symptoms were suggestive of parvoviruses infection. A qualitative polymerase chain reaction testing for B19 in serum sample revealed positive results for B19 virus DNA. CONCLUSION: This case report suggests that the diagnostic process for parvovirus B19 in renal transplant recipients should include a polymerase chain reaction assay to detect B19-DNA, since specific serological tests may be unreliable given their impaired humoral responses. These results also indicate the importance of considering parvovirus B19 infection in the differential diagnosis of persistent anemia in transplanted patients.

Urinary 11-dehydro thromboxane B2 levels in type 2 diabetic patients before and during aspirin intake.

BACKGROUND: Diabetic patients commonly present an increased risk for cardiovascular events, for which aspirin is the most frequently used medication for primary prevention. Urinary 11-dehydro thromboxane (11-dhTXB2) concentrations assess the effect of aspirin on platelets and identify patients who are at risk of cardiovascular events. The present study investigated whether or not type 2 diabetic patients who took a daily dose of 100mg of aspirin had a significant reduction in urinary 11-dhTXB2 concentrations and whether these results were associated with clinical and laboratory variables. METHODS: Eighty-one type 2 diabetic patients were enrolled in the study. Laboratory tests included the determination of lipidic profile, glycated hemoglobin, platelets count, molecular analysis for both GPIIbIIIa and COX-1 polymorphisms, and urinary 11-dhTXB2. RESULTS: Patients' median value for urinary 11-dhTXB2 before aspirin intake was 179 pg/mg of creatinine. After 15days taking aspirin, the patients presented median of 51 pg/mg of creatinine, thus revealing a significant difference between medians (p=0.00). A reduction of 95% in urinary 11-dhTXB2 concentrations could only be identified in 4 patients (5%). A BMI of ≥ 26 presented a significant association with a reduction of urinary 11-dhTXB2 concentrations (p=0.010), as shown by the multiple logistic regression model. Other clinical and laboratory variables showed no association. CONCLUSIONS: Regardless of the mechanisms related to aspirin non-responsiveness, most patients enrolled in the present study also presented a reduced or minimal response to low-dose aspirin therapy, thereby indicating a clear variability related to aspirin effectiveness. Moreover, BMI appears to be independently associated to the reduction of urinary 11-dhTXB2 concentrations in type 2 diabetic patients taking aspirin.