Plasma immune mediators as laboratorial biomarkers for Sickle Cell Disease patients according to the hydroxyurea therapy and disease severity.

In the present work, the impact of Sickle Cell Disease (SCD) degrees of severity, as well hydroxyurea treatment on the systemic immunological signatures of patients was evaluated. Based on a high-throughput chemokine, cytokine and growth factor multiplex analysis, it was possible to obtain the systemic immunological profile of patients with SCD (n = 40), treated or not with hydroxyurea, as compared to healthy controls (n = 40). Overall, SCD patients with severe disease displayed increased levels of almost all biomarkers analyzed. Our data demonstrated that CXCL8, CCL3 and CXCL10 were pointed out as universal biomarkers of SCD. The results also indicated that HU-untreated patients with indication of HU-therapy display a more prominent increase on plasma immune mediators in a similar way as those with severe SCD disease. Together, these findings provided a comprehensive landscape of evidence that may have implications for further therapeutic strategies and SCD clinical management.

Endothelial dysfunction biomarkers in sickle cell disease: is there a role for ADMA and PAI-1?

Within the spectrum of sickle cell disease (SCD) are sickle cell anemia (SCA), presence of hemoglobin SS (HbSS), hemoglobin SC disease (HbSC), and sickle cell ß-thalassemia (Sß-thal). Asymmetric dimethylarginine (ADMA) competitively inhibits the binding of arginine to NOS, reducing NO production. In patients with HbSS, increased levels of ADMA have been reported, as well as changes in many hemostatic biomarkers, including the plasminogen activator inhibitor type 1 (PAI-1). We hypothesized that high levels of ADMA and PAI-1 may be associated with more severe SCD. Thus, ADMA and PAI-1 levels were determined in 78 individuals including 38 adult patients with SCD and 40 control subjects. Higher levels of ADMA were shown in HbSS and Sß-thal patients compared to controls. Concerning PAI-1, all patients showed high levels of PAI-1 compared to controls. As a role of NO in the pathogenesis of SCD has already been established, we concluded that high levels of ADMA should compromise, at least in part, NO synthesis, resulting in endothelial dysfunction. Elevated plasma levels of PAI-1 in all patients may indicate not only endothelial dysfunction but also a hypofibrinolytic state favoring thrombotic complications. Finally, high levels of ADMA and PAI-1 may be associated with more severe SCD.

ADAMTS-13-VWF axis in sickle cell disease patients.

Sickle cell disease (SCD) comprises a group of genetic disorders characterized by the presence of the hemoglobin (Hb) S in homozygosis or in heterozygosis with some other Hb variant or in interaction with thalassemia. SCD is characterized by a very complex pathophysiology, which determines a wide variability of clinical manifestations, including a chronic state of hypercoagulability responsible for the increased risk of thromboembolic events. ADAMTS13 and von Willebrand factor (VWF) play an important role in arterial and venous thrombosis. Thus, the aim of this study was to understand how the ADAMTS13-VWF axis behaves in sickle cell disease, as well as whether there is an association of these markers with the use of hydroxyurea (HU). This is a cross-sectional study conducted with 40 patients diagnosed with SCD and 40 healthy individuals. The analysis of the ADAMTS13-VWF axis was comparatively performed between groups of patients and controls and, afterwards, between patients with SCD who were users and non-users of HU. ADAMTS13 activity, ADAMTS13 activity/VWF:Ag, and ADAMTS13:Ag/VWF:Ag ratios were significantly lower and VWF:Ag levels significantly higher in SCD patients when compared to the controls. There was no statistically significant difference in ADAMTS13:Ag and VWF collagen binding (VWF:CB) levels between the groups evaluated. Among the categories of HU use, there was no statistically significant difference in any of the evaluated markers. As a conclusion, we could observe that the ADAMTS13-VWF axis is altered in SCD when compared to healthy individuals and that there is no association between these markers and the use of HU.

Antibiotic resistance profile and occurrence of AmpC between Pseudomonas aeruginosa isolated from a domestic full-scale WWTP in southeast Brazil.

Wastewater treatment plants (WWTPs) represent an important reservoir of antibiotic resistance determinants. Although many studies have been conducted to evaluate resistance profiles in Enterobacteriaceae isolates from this setting, the dynamics of this phenomenon are poorly known to the bacterium Pseudomonas aeruginosa. Here we aimed to evaluate the resistance profiles and the production of AmpC ß-lactamase in P. aeruginosa isolates from a domestic full-scale WWTP. Samples of the raw sewage and effluent were collected and the bacterium P. aeruginosa was isolated on cetrimide agar. Susceptibility to ß-lactams, fluoroquinolones and aminoglycosides was evaluated by the disc diffusion method, and the presence of AmpC ß-lactamase was investigated phenotypically and by molecular method. We recovered 27 isolates of P. aeruginosa. Of these, 81.5% were susceptible to all antimicrobials tested. However, a considerable rate of resistance to carbapenems (11%) was found among the isolates. Twenty-two isolates were positive in the phenotypic test for inducible AmpC ß-lactamase but the blaampc gene was only identified in four isolates, suggesting the presence of other independent resistance mechanisms besides this ß-lactamase. In summary, we have shown that P. aeruginosa isolates from a domestic WWTP represents a potential reservoir of blaampC genes and other resistance determinants, including those that result in low susceptibility to carbapenems and aminoglycosides.

Inflammatory Hematological Indices, Cardiovascular Disease and Mortality: A Narrative Review. / Índices Hematológicos Inflamatórios, Doenças Cardiovasculares e Mortalidade: Uma Revisão Narrativa.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, which generates a significant economic burden of billions per year on the healthcare system. Chronic inflammation is known for its importance in the pathogenesis of atherosclerosis and CVDs. Currently, inflammatory hematologic indices, obtained through the results of the complete blood count (CBC), have been characterized as potential prognostic factors for mortality in CVD. These indexes are calculated from neutrophil, lymphocyte, platelet, and monocyte counts, are easily accessible, have simple calculations, and have low cost, which facilitates their application in practice. The aim of this paper was prepare a synthesis of studies that investigated the relationship of inflammatory hematologic indices with cardiovascular risk and mortality. The search was been conducted in PubMed, Scopus, Embase, Web of Science, and Virtual Health Library (VHL) databases. Studies that investigated the association between inflammatory hematologic indices with cardiovascular risk and mortality were been selected. 1,470 studies were obtained in the search, with only 23 being eligible. We found that the hematological index most associated with overall mortality, cardiovascular events, and cardiovascular mortality was the systemic immune-inflammation index (SII) followed by the systemic inflammatory response index (SIRI). The hematological inflammatory indices proved advantageous for screening and identifying patients who have high cardiovascular risk and mortality risk, and may be useful in directing the treatment of these patients, obtaining information about prognosis, and improving risk stratification.

As doenças cardiovasculares (DCV) são a principal causa de morte em todo o mundo, o que gera um fardo económico significativo de bilhões por ano no sistema de saúde. A inflamação crônica é conhecida por sua importância na patogênese da aterosclerose e das DCV. Atualmente, os índices hematológicos inflamatórios, obtidos através dos resultados do hemograma completo (HC), têm sido caracterizados como potenciais fatores prognósticos para mortalidade nas DCV. Esses índices são calculados a partir da contagem de neutrófilos, linfócitos, plaquetas e monócitos, são de fácil acesso, possuem cálculos simples e têm baixo custo, o que facilita sua aplicação na prática. O objetivo deste trabalho foi preparar uma síntese de estudos que investigaram a relação dos índices hematológicos com o risco cardiovascular e mortalidade. A busca foi realizada nas bases de dados PubMed, Scopus, Embase, Web of Science e Biblioteca Virtual em Saúde (BVS). Foram selecionados estudos que investigaram a associação entre índices hematológicos inflamatórios com risco cardiovascular e mortalidade. Foram obtidos 1.470 estudos na busca, sendo apenas 23 elegíveis. Descobrimos que o índice hematológico mais associado à mortalidade geral, eventos cardiovasculares e mortalidade cardiovascular foi o índice de inflamação imunológica sistêmica (SII), seguido pelo índice de resposta inflamatória sistêmica (SIRI). Os índices inflamatórios hematológicos mostraram-se vantajosos para triagem e identificação de pacientes com alto risco cardiovascular e risco de mortalidade, podendo ser úteis no direcionamento do tratamento desses pacientes, na obtenção de informações sobre prognóstico e na melhoria da estratificação de risco.

Inflammation and all-cause mortality in patients undergoing peritoneal dialysis.

OBJECTIVE: This study aimed to evaluate inflammatory biomarkers in patients undergoing peritoneal dialysis and investigate their association with all-cause mortality or transfer to hemodialysis. METHODS: This prospective cohort study included 43 patients undergoing peritoneal dialysis. Plasma levels of cytokines were measured using flow cytometry and capture enzyme-linked immunosorbent assay. Biomarkers were categorized based on their respective median values. Survival analysis was conducted using the Kaplan-Meier estimator, considering two outcomes: all-cause mortality and transfer to hemodialysis. RESULTS: After adjusting for confounding factors, plasma levels above the median of the levels of CCL2 and plasma, as well as below the median of TNF-α, and the median of dialysate IL-17 levels, were associated with an increased risk of experiencing the specified outcomes after approximately 16 months of follow-up. CONCLUSION: These findings suggest that inflammatory biomarkers may be a valuable tool for predicting all-cause mortality and transfer to hemodialysis in patients undergoing peritoneal dialysis.

Development and evaluation of sustained-release etoposide-loaded poly(ε-caprolactone) implants.

Poly(ε-caprolactone) implants containing etoposide, an important chemotherapeutic agent and topoisomerase II inhibitor, were fabricated by a melt method and characterized in terms of content uniformity, morphology, drug physical state, and sterility. In vitro and in vivo drug release from the implants was also evaluated. The cytotoxic activity of implants against HeLa cells was studied. The short-term tolerance of the implants was investigated after subcutaneous implantation in mice. The original chemical structure of etoposide was preserved after incorporation into the polymeric matrix, in which the drug was dispersed uniformly. Etoposide was present in crystalline form in the polymeric implant. In vitro release study showed prolonged and controlled release of etoposide, which showed cytotoxicity activity against HeLa cells. After implantation, good correlation between in vitro and in vivo drug release was found. The implants demonstrated good short-term tolerance in mice. These results tend to show that etoposide-loaded implants could be potentially applied as a local etoposide delivery system.

Thrombin generation assay as a biomarker of cardiovascular outcomes and mortality: A narrative review.

Cardiovascular diseases (CVDs) are currently the leading cause of death worldwide. Therefore, there is interest in the search for cardiovascular risk markers that contribute to the early diagnosis, monitoring and prevention of cardiovascular events. Considering that CVDs present in their pathophysiology a strong interaction between inflammation and hemostasis, thrombin, a key enzyme in the clotting process can be thought as a possible biomarker of cardiovascular risk. The thrombin generation assay (TGA) by the Calibrated Automated Thrombogram (CAT) method has been used in numerous prospective studies. It is a relatively recent laboratory tool capable of globally evaluating the functioning of the hemostatic system through the determination of thrombin generation for investigating the contribution of procoagulants and natural anticoagulants, in addition to the effect of different drugs and a range of factors that interfere in this system. The analysis of thrombin generation can be a promising tool for estimating the risk of thrombotic diseases, although the association of TGA with arterial thrombosis has only recently attracted interest and remains to be better understood. The association between thrombin generation and cardiovascular events, especially acute myocardial infarction (AMI) and stroke, all-cause and cardiovascular mortality is still poorly investigated and the results are often inconsistent. Assessing the relationship between TGA and CVDs may not only contribute to increasing knowledge of the pathophysiological process that leads to coronary and cerebrovascular diseases, but may also suggest a new approach to prevention. In this article we review and summarize the results of the main studies that evaluated whether TGA parameters were associated with cardiovascular events, cardiovascular mortality and all-cause mortality. Possible contributing factors to the observed inconsistencies were also speculated.

Performance and reference intervals of thrombin generation test: results from the Brazilian longitudinal study of adult health (ELSA-Brasil). A cross-sectional study.

BACKGROUND: The thrombin generation test (TGT) has shown promise for investigation of hemorrhagic and thrombotic diseases. However, despite its potential, it still needs standardization. Moreover, few studies have established reference values for TGT parameters. In Brazil, these values have not yet been established. OBJECTIVE: To determine TGT performance and reference intervals for TGT parameters in healthy individuals. DESIGN AND SETTING: Cross-sectional study conducted among participants in the Brazilian Longitudinal Study of Adult Health (Estudo Longitudinal de Saúde do Adulto, ELSA-Brasil). METHODS: The reference sample consisted of 620 healthy individuals. The calibrated automated thrombogram (CAT) method, under low and high tissue factor (TF) conditions, was used to assess thrombin generation. Test performance was analyzed using intra and interassay coefficients of variation (CV) and reference intervals were calculated using the nonparametric method proposed by the International Federation of Clinical Chemistry and the Clinical and Laboratory Standards Institute. RESULTS: The intraassay CV ranged from 1.4% to 2.2% and the interassay CV, 6.8% to 14.7%. The reference intervals for TGT parameters under low and high TF conditions were, respectively: lagtime: 3.0-10.3 and 1.4-3.7 min; endogenous thrombin potential (ETP): 1134.6-2517.9 and 1413.6-2658.0 nM.min; normalized ETP: 0.6-1.3 and 0.7-1.4; peak: 103.2-397.7 and 256.4-479.0 nM; normalized peak: 0.3-1.3 and 0.7-1.2; and time-to-peak: 5.6-16.0 and 3.4-6.7 min. These parameters were categorized relative to sex. CONCLUSION: TGT performance was adequate and the proposed reference intervals were similar to those of other studies. Our findings may be useful for consolidating the TGT, through contributing to its standardization and validation.

Thrombin generation in vivo and ex vivo in sickle cell disease patients.

Activation of coagulation is an important hallmark of sickle cell disease (SCD) and it is believed that hypercoagulability plays a role to the disease pathophysiology. Studies have sought to identify how hemostatic biomarkers are expressed in SCD, however, the results are inconclusive. In this context, our objective was to evaluate the thrombin generation in vivo and ex vivo in SCD patients and the association between these biomarkers and the use of HU. This cross-sectional study was carried out with patients diagnosed with SCD, users or not of Hydroxyurea (HU), and healthy individuals as controls. D dimer (D-Di) was evaluated by ELISA and (TGT) thrombin generation test by CAT method. D-Di plasma levels were significantly higher in SCD patients when compared to the controls. TGT parameters such as peak, ETP and normalized ETP at low TF concentration and time-to-peak, peak, ETP and normalized ETP values at high TF concentration were lower in SCD patients than in controls. In contrast, the normalized activated protein C sensitivity ratio (nAPCsr) was higher in patients compared to controls, indicating resistance to the action of this natural anticoagulant. Regarding the use of HU, comparing users and non-users of this drug, no difference was observed in D-Di levels and in most TGT parameters. Our data analyzed together allow us to conclude that patients with SCD present a state of hypercoagulability in vivo due to the higher levels of D-Di and resistance to APC assessed ex vivo which is consistent with the coagulation imbalance described in SCD patients.

Performance and reference intervals of thrombin generation test: results from the Brazilian longitudinal study of adult health (ELSA-Brasil). A cross-sectional study

ABSTRACT BACKGROUND: The thrombin generation test (TGT) has shown promise for investigation of hemorrhagic and thrombotic diseases. However, despite its potential, it still needs standardization. Moreover, few studies have established reference values for TGT parameters. In Brazil, these values have not yet been established. OBJECTIVE: To determine TGT performance and reference intervals for TGT parameters in healthy individuals. DESIGN AND SETTING: Cross-sectional study conducted among participants in the Brazilian Longitudinal Study of Adult Health (Estudo Longitudinal de Saúde do Adulto, ELSA-Brasil). METHODS: The reference sample consisted of 620 healthy individuals. The calibrated automated thrombogram (CAT) method, under low and high tissue factor (TF) conditions, was used to assess thrombin generation. Test performance was analyzed using intra and interassay coefficients of variation (CV) and reference intervals were calculated using the nonparametric method proposed by the International Federation of Clinical Chemistry and the Clinical and Laboratory Standards Institute. RESULTS: The intraassay CV ranged from 1.4% to 2.2% and the interassay CV, 6.8% to 14.7%. The reference intervals for TGT parameters under low and high TF conditions were, respectively: lagtime: 3.0-10.3 and 1.4-3.7 min; endogenous thrombin potential (ETP): 1134.6-2517.9 and 1413.6-2658.0 nM.min; normalized ETP: 0.6-1.3 and 0.7-1.4; peak: 103.2-397.7 and 256.4-479.0 nM; normalized peak: 0.3-1.3 and 0.7-1.2; and time-to-peak: 5.6-16.0 and 3.4-6.7 min. These parameters were categorized relative to sex. Conclusion: TGT performance was adequate and the proposed reference intervals were similar to those of other studies. Our findings may be useful for consolidating the TGT, through contributing to its standardization and validation.

Associação entre a presença de anemia ferropriva com variáveis socioeconômicas e rendimento escolar / Association between the occurence of iron-deficiency anemia with socioeconomic variables and school performance

Modelo do estudo: Observacional transversal. Objetivo: Avaliar a associação entre a presença de anemia ferropriva com variáveis socioeconômicas e rendimento escolar. Método: Foram incluídas no estudo 124 crianças com idade entre seis e oito anos, estudantes do ensino fundamental de escolas municipais, as quais foram divididas em dois grupos de acordo com a presença (n=32) ou ausência de anemia (n=92). Os níveis de hemoglobina e ferro sérico foram determinados por método colorimétrico, a contagem de hemácias foi realizada utilizando a câmara de Neubauer, o hematócrito foi avaliado utilizando centrífuga de microhematócrito, e foram calculados os índices hematimétricos volume corpuscular médio, hemoglobina corpuscular média e concentração de hemoglobina corpuscular média. O desempenho escolar das crianças foi fornecido pelas escolas participantes e as variáveis socioeconômicas foram obtidas através de preenchimento de ficha clínica e do questionário socioeconômico da Associação Brasileira das Empresas de Pesquisa pelos pais ou responsáveis. Resultados: A prevalência de anemia ferropriva nos escolares foi de 25,8% que é considerada pelos parâmetros da OMS uma prevalência moderada. Foi observada uma maior proporção de crianças sem anemia que apresentaram melhores conceitos escolares e que pertencem aos níveis socioeconômicos mais altos do que de crianças com anemia. Contudo, não foram observadas diferenças estatisticamente significativas entre os grupos com relação ao rendimento escolar e as variáveis socioeconômicas. Conclusão: Uma prevalência moderada de anemia ferropriva foi encontrada nas crianças com idade entre seis e oitos anos, entretanto, não foi observada uma associação significativa entre a anemia ferropriva com variáveis socioeconômicas e o rendimento escolar. (AU)

Study design: Cross-sectional observational. Objective: Evaluate the association between the occurence of iron-deficiency anemia with socioeconomic variables and school performance. Method: They were included in the study 124 children aged between six and eight years old, municipal elementary school students, which were divided in two groups according to the presence (n=32) or absence of anemia (n=92). Hemoglobin and serum iron levels were determined by colorimetric method, red blood cells count was performed using Neubauer chamber, hematocrit was evaluated using microhematocrit centrifuge, and mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration hematimetric indexes were calculated. The school performance of children was provided by participating schools and socioeconomic variables were obtained by filling out the clinic file and the socioeconomic questionnaire of Brazilian Association of Research Companies by parents or guardians. Results: The prevalence of iron-deficiency anemia in school children was 25.8%, which is considered to be moderate. The proportion of better school grades was higher in children without anemia and in those belonging to the upper socioeconomic levels. However, it was not observed statistically differences between groups regarding school performance and socioeconomic variables. Conclusion: A moderate prevalence of iron-deficiency anemia was found in children aged between six and eight years old, however, it was not observed a significant association between irondeficiency anemia with socioeconomic variables and school performance. (AU)