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1.
Bioorg Chem ; 146: 107283, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513324

RESUMO

The breast cancer resistance protein (BCRP/ABCG2) transporter mediates the efflux of numerous antineoplastic drugs, playing a central role in multidrug resistance related to cancer. The absence of successful clinical trials using specific ABCG2 inhibitors reveals the urge to identify new compounds to attend this critical demand. In this work, a series of 13 magnolol derivatives was tested as ABCG2 inhibitors. Only two compounds, derivatives 10 and 11, showed partial and complete ABCG2 inhibitory effect, respectively. This inhibition was selective toward ABCG2, since none of the 13 compounds inhibited neither P-glycoprotein nor MRP1. Both inhibitors (10 and 11) were not transported by ABCG2 and demonstrated a low cytotoxic profile even at high concentrations (up to 100 µM). 11 emerged as the most promising compound of the series, considering the ratio between cytotoxicity (IG50) and ABCG2 inhibition potency (IC50), showing a therapeutic ratio (TR) higher than observed for 10 (10.5 versus 1.6, respectively). This derivative showed a substrate-independent and a mixed type of inhibition. The effect of compound 11 on the ABCG2 ATPase activity and thermostability revealed allosteric protein changes. This compound did not affect the expression levels of ABCG2 and increased the binding of the conformational-sensitive antibody 5D3. A docking study showed that 11 did not share the same binding site with ABCG2 substrate mitoxantrone. Finally, 11 could revert the chemoresistance to SN-38 mediated by ABCG2.


Assuntos
Antineoplásicos , Compostos de Bifenilo , Neoplasias da Mama , Lignanas , Humanos , Feminino , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo
2.
Int J Biochem Mol Biol ; 14(4): 51-61, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736389

RESUMO

Type 1 diabetes mellitus (T1DM), associated with autoimmune destruction of pancreatic ß cells, is observed in children and adolescents. OBJECTIVE: We investigated the potential association of the apolipoprotein M (APOM) polymorphisms rs707921, rs805264, rs805296, rs805297, and rs9404941 in childhood-onset T1DM (n = 144) and compared them to those in healthy (mostly Euro-Brazilian) children (n = 168). METHODS: This project was approved by the Ethics Committee of the Federal University of Parana (CAAE 24676613.6.0000.0102). Genotyping was performed using PCR-restriction fragment length polymorphisms (rs805296 and rs9404941) and TaqMan probes (rs707921, rs805264, and rs805297). RESULTS: All polymorphisms were in Hardy-Weinberg equilibrium. In the codominant model, no significant differences (P > 0.05) were observed in genotype and allele frequencies between healthy controls and children with T1DM. The minor allele frequencies (95% CI) for healthy subjects were rs707921 (A, 10.7%; 7-14%), rs805264 (A, 6.5%; 4-9%), rs805296 (C, 3.6%; 2-6%), rs805297 (A, 22.6%; 22-31%), and rs9404941 (C, 2.7%; 1-4%). The frequencies of the rs805297 A allele and rs805296 C allele were similar to those of other Caucasian populations; both the rs707921 and rs805264 A alleles were similar to American and Latin American populations, whereas that of the rs9404941 C allele was lower than that observed in the Caucasian and Asian populations. CONCLUSIONS: Haplotype analysis suggests that rs805297-C, rs9404941-T, rs805296-T, rs805264-G, and rs707921-C conferred risk (OR: 4.25; 95% CI: 1.81-10.1) to childhood-onset T1DM in the Euro-Brazilian population.

3.
Pharmaceutics ; 15(4)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37111745

RESUMO

Inhibition of ABC transporters is a promising approach to overcome multidrug resistance in cancer. Herein, we report the characterization of a potent ABCG2 inhibitor, namely, chromone 4a (C4a). Molecular docking and in vitro assays using ABCG2 and P-glycoprotein (P-gp) expressing membrane vesicles of insect cells revealed that C4a interacts with both transporters, while showing selectivity toward ABCG2 using cell-based transport assays. C4a inhibited the ABCG2-mediated efflux of different substrates and molecular dynamic simulations demonstrated that C4a binds in the Ko143-binding pocket. Liposomes and extracellular vesicles (EVs) of Giardia intestinalis and human blood were used to successfully bypass the poor water solubility and delivery of C4a as assessed by inhibition of the ABCG2 function. Human blood EVs also promoted delivery of the well-known P-gp inhibitor, elacridar. Here, for the first time, we demonstrated the potential use of plasma circulating EVs for drug delivery of hydrophobic drugs targeting membrane proteins.

4.
J Vis Exp ; (191)2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36715403

RESUMO

This paper describes a novel, simple, and low-cost device to perform in vitro photodynamic therapy (PDT) assays, named the PhotoACT. The device was built using a set of conventional programmable light-emitting diodes (LEDs), a liquid crystal display (LCD) module, and a light sensor connected to a commercial microcontroller board. The box-based structure of the prototype was made with medium-density fiberboards (MDFs). The internal compartment can simultaneously allocate four cell culture multiwell microplates. As a proof of concept, we studied the cytotoxic effect of the photosensitizer (PS) verteporfin against the HeLa cell line in two-dimensional (2D) culture. HeLa cells were treated with increasing concentrations of verteporfin for 24 h. The drug-containing supernatant medium was discarded, the adherent cells were washed with phosphate-buffered saline (PBS), and drug-free medium was added. In this study, the effect of verteporfin on cells was examined either without light exposure or after exposure for 1 h to light using red-green-blue (RGB) values of 255, 255, and 255 (average fluence of 49.1 ± 0.6 J/cm2). After 24 h, the cell viability was assessed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. Experimental results showed that exposure of cells treated with verteporfin to the light from the device enhances the drug's cytotoxic effect via a mechanism mediated by reactive oxygen species (ROS). In addition, the use of the prototype described in this work was validated by comparing the results with a commercial PDT device. Thus, this LED-based photodynamic therapy prototype represents a good alternative for in vitro studies of PDT.


Assuntos
Antineoplásicos , Fotoquimioterapia , Humanos , Verteporfina/farmacologia , Células HeLa , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Técnicas de Cultura de Células
5.
EXCLI J ; 22: 1155-1172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38204967

RESUMO

A current clinical challenge in cancer is multidrug resistance (MDR) mediated by ABC transporters. Breast cancer resistance protein (BCRP) or ABCG2 transporter is one of the most important ABC transporters implicated in MDR and the use of inhibitors is a promising approach to overcome the resistance in cancer. This study aimed to characterize the molecular mechanism of ABCG2 inhibitors identified by a repurposing drug strategy using antiviral, anti-inflammatory and antiparasitic agents. Lopinavir and ivermectin can be considered as pan-inhibitors of ABC transporters, since both compounds inhibited ABCG2, P-glycoprotein and MRP1. They inhibited ABCG2 activity showing IC50 values of 25.5 and 23.4 µM, respectively. These drugs were highly cytotoxic and not transported by ABCG2. Additionally, these drugs increased the 5D3 antibody binding and did not affect the mRNA and protein expression levels. Cell-based analysis of the type of inhibition suggested a non-competitive inhibition, which was further corroborated by in silico approaches of molecular docking and molecular dynamics simulations. These results showed an overlap of the lopinavir and ivermectin binding sites on ABCG2, mainly interacting with E446 residue. However, the substrate mitoxantrone occupies a different site, binding to the F436 region, closer to the L554/L555 plug. In conclusion, these results revealed the mechanistic basis of lopinavir and ivermectin interaction with ABCG2. See also the Graphical abstract(Fig. 1).

6.
Biometals ; 35(5): 903-919, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35778658

RESUMO

Diabetes mellitus, a complex and heterogeneous disease associated with hyperglycemia, is a leading cause of mortality and reduces life expectancy. Vanadium complexes have been studied for the treatment of diabetes. The effect of complex [VO(bpy)(mal)]·H2O (complex A) was evaluated in a human hepatocarcinoma (HepG2) cell line and in streptozotocin (STZ)-induced diabetic male Wistar rats conditioned in seven groups with different treatments (n = 10 animals per group). Electron paramagnetic resonance and 51V NMR analyses of complex A in high-glucose Dulbecco's Modified Eagle Medium (DMEM) revealed the oxidation and hydrolysis of the oxidovanadium(IV) complex over a period of 24 h at 37 °C to give low-nuclearity vanadates "V1" (H2VO4-), "V2" (H2V2O72-), and "V4" (V4O124-). In HepG2 cells, complex A exhibited low cytotoxic effects at concentrations 2.5 to 7.5 µmol L-1 (IC50 10.53 µmol L-1) and increased glucose uptake (2-NBDG) up to 93%, an effect similar to insulin. In STZ-induced diabetic rats, complex A at 10 and 30 mg kg-1 administered by oral gavage for 12 days did not affect the animals, suggesting low toxicity or metabolic impairment during the experimental period. Compared to insulin treatment alone, complex A (30 mg kg-1) in association with insulin was found to improve glycemia (30.6 ± 6.3 mmol L-1 vs. 21.1 ± 8.6 mmol L-1, respectively; p = 0.002), resulting in approximately 30% additional reduction in glycemia. The insulin-enhancing effect of complex A was associated with low toxicity and was achieved via oral administration, suggesting the potential of complex A as a promising candidate for the adjuvant treatment of diabetes.


Assuntos
Diabetes Mellitus Experimental , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Humanos , Hipoglicemiantes/efeitos adversos , Insulina/metabolismo , Insulina/farmacologia , Malatos , Masculino , Ratos , Ratos Wistar , Estreptozocina , Vanadatos/química , Vanádio/química , Vanádio/farmacologia
7.
FEBS Lett ; 596(3): 381-399, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34939198

RESUMO

A promising strategy to overcome multidrug resistance is the use of inhibitors of ABC drug transporters. For this reason, we evaluated the polyoxovanadates (POVs) [V10 O28 ]6- (V10 ), [H6 V14 O38 (PO4 )]5- (V14 ), [V15 O36 Cl]6- (V15 ) and [V18 O42 I]7- (V18 ) as inhibitors of three major multidrug resistance-linked ABC transporters: P-glycoprotein (P-gp), ABCG2 and MRP1. All of the POVs selectively inhibited P-gp. V10 and V18 were the two most promising compounds, with IC50 values of transport inhibition of 25.4 and 22.7 µm, respectively. Both compounds inhibited P-gp ATPase activity, with the same IC50 value of 1.26 µm. V10 and V18 triggered different conformational changes in the P-gp protein with time-dependent inhibition, which was confirmed using the synthesized salt of V10 with rhodamine B, RhoB-V10 . The hydrophilic nature of POVs supports the hypothesis that these compounds target an unusual ligand-binding site, opening new possibilities in the development of potent modulators of ABC transporters.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP
8.
Chem Biol Interact ; 351: 109718, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34717915

RESUMO

The ABCG2 transporter plays a pivotal role in multidrug resistance, however, no clinical trial using specific ABCG2 inhibitors have been successful. Although ABC transporters actively extrude a wide variety of substrates, photodynamic therapeutic agents with porphyrinic scaffolds are exclusively transported by ABCG2. In this work, we describe for the first time a porphyrin derivative (4B) inhibitor of ABCG2 and capable to overcome multidrug resistance in vitro. The inhibition was time-dependent and 4B was not itself transported by ABCG2. Independently of the substrate, the porphyrin 4B showed an IC50 value of 1.6 µM and a mixed type of inhibition. This compound inhibited the ATPase activity and increased the binding of the conformational-sensitive antibody 5D3. A thermostability assay confirmed allosteric protein changes triggered by the porphyrin. Long-timescale molecular dynamics simulations revealed a different behavior between the ABCG2 porphyrinic substrate pheophorbide a and the porphyrin 4B. Pheophorbide a was able to bind in three different protein sites but 4B showed one binding conformation with a strong ionic interaction with GLU446. The inhibition was selective toward ABCG2, since no inhibition was observed for P-glycoprotein and MRP1. Finally, this compound successfully chemosensitized cells that overexpress ABCG2. These findings reinforce that substrates may be a privileged source of chemical scaffolds for identification of new inhibitors of multidrug resistance-linked ABC transporters.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Adenosina Trifosfatases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Porfirinas/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Células HEK293 , Humanos , Irinotecano/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Porfirinas/química , Porfirinas/metabolismo , Ligação Proteica , Conformação Proteica/efeitos dos fármacos
9.
Front Microbiol ; 12: 769380, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912316

RESUMO

Aeromonas are Gram-negative rods widely distributed in the environment. They can cause severe infections in fish related to financial losses in the fish industry, and are considered opportunistic pathogens of humans causing infections ranging from diarrhea to septicemia. The objective of this study was to determine in silico the contribution of genomic islands to A. hydrophila. The complete genomes of 17 A. hydrophila isolates, which were separated into two phylogenetic groups, were analyzed using a genomic island (GI) predictor. The number of predicted GIs and their characteristics varied among strains. Strains from group 1, which contains mainly fish pathogens, generally have a higher number of predicted GIs, and with larger size, than strains from group 2 constituted by strains recovered from distinct sources. Only a few predicted GIs were shared among them and contained mostly genes from the core genome. Features related to virulence, metabolism, and resistance were found in the predicted GIs, but strains varied in relation to their gene content. In strains from group 1, O Ag biosynthesis clusters OX1 and OX6 were identified, while strains from group 2 each had unique clusters. Metabolic pathways for myo-inositol, L-fucose, sialic acid, and a cluster encoding QueDEC, tgtA5, and proteins related to DNA metabolism were identified in strains of group 1, which share a high number of predicted GIs. No distinctive features of group 2 strains were identified in their predicted GIs, which are more diverse and possibly better represent GIs in this species. However, some strains have several resistance attributes encoded by their predicted GIs. Several predicted GIs encode hypothetical proteins and phage proteins whose functions have not been identified but may contribute to Aeromonas fitness. In summary, features with functions identified on predicted GIs may confer advantages to host colonization and competitiveness in the environment.

10.
J Diabetes Metab Disord ; 20(1): 611-620, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34222081

RESUMO

PURPOSE: This prospective study aimed to detect and identify plasma proteins differentially expressed between groups of Brazilian diagnosed with type 1 (T1DM), type 2 (T2DM) diabetes with good and poor glycemic control and the non-diabetic group denominated control group (CG). METHODS: Patients with T1DM and T2DM were subdivided according to their glycated haemoglobin (HbA1c) level: ≥ 53 mmol/mol and < 53 mmol/mol. Each subgroup was composed of ten subjects (n = 10). The plasma from each subgroup was pooled and depleted of albumin and IgG. The reminiscent proteins were quantified and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The relative volume of protein bands was determined by densitometry analysis, and those with differential abundance were identified by MALDI-TOF mass spectrometry. RESULTS: Alpha 2 - Macroglobulin (AMG) was 1.3-fold more abundant in T1DM with HbA1c ≥ 53 mmol/mol and < 53 mmol/mol and 1.4-fold more abundant in T2DM with HbA1c ≥ 53 mmol/mol compared to CG. Ceruloplasmin (Cp) and Haptoglobin (Hp) were overexpressed above 1.5-fold in all DM subgroups. Cp in T1DM and Hp in both types of DM were more expressed in HbA1c ≥ 53 mmol/mol than <53 mmol/mol. Apolipoprotein A-I (Apo A-I) was upregulated only in T2DM subgroups. CONCLUSION: In summary, three positive acute-phase proteins, AMG, Cp and Hp were more abundant in diabetic individuals regardless of the diabetes type. The highest Hp abundance in both types of DM with HbA1c ≥ 53 mmol/mol, reinforces Hp as a possible biomarker associated with diabetic complications.

11.
Rev. bras. anal. clin ; 53(2): 138-142, 20210630. ilus
Artigo em Português | LILACS | ID: biblio-1348698

RESUMO

A pandemia da COVID-19 tem tido um impacto devastador em todo o mundo e levou ao rápido desenvolvimento de testes diagnósticos. Diferentes tecnologias vêm sendo utilizadas para a detecção de imunoglobulinas frente à infecção por SARS-CoV-2. Ensaios imunoenzimáticos (ELISA), quimioluminescentes e imunocromatográficos estão disponíveis e, no geral, apresentam poder diagnóstico limitado, principalmente para a detecção de IgA. A citometria de fluxo tem surgido como alternativa para o desenvolvimento de métodos sensíveis e específicos para a COVID-19 aplicados para diagnóstico, triagem e estratificação da doença. A citometria de fluxo é uma tecnologia óptica baseada em laser que detecta características físico-químicas de células ou partículas em um fluido heterogêneo. O artigo explora a citometria de fluxo para o diagnóstico da COVID-19 em duas estratégias para a detecção de anticorpos no soro ou plasma, uma utilizando antígenos virais expressos na superfície de células de mamíferos e outra com estes elementos imobilizados em microesferas (beads). A possibilidade de detecção rápida de múltiplos anticorpos simultaneamente, com pequeno volume de amostra e elevada sensibilidade e especificidade, torna a citometria de fluxo uma metodologia promissora para o laboratório clínico, como ferramenta de referência para auxiliar na contenção do processo pandêmico da COVID-19 e futuros eventos similares.


The COVID-19 pandemic has had a devastating impact around the world and has led to the rapid development of diagnostic tests. Different technologies have been used to detect immunoglobulins produced against SARS-CoV-2 infection. Immunoenzymatic (ELISA), chemiluminescent and immunochromatographic assays are available and, in general, they have limited diagnostic accuracy, especially for the detection of IgA. Flow cytometry has emerged as an alternative for the development of sensitive and specific methods for COVID-19 applied for diagnosis, screening and stratification of the disease. Flow cytometry is a laser-based optical technology that detects physicochemical characteristics of cells or particles in a heterogeneous fluid. The article explores flow cytometry for the diagnosis of COVID-19 in two strategies for detecting antibodies in serum or plasma, the first one using viral antigens expressed on the surface of mammalian cells and the other one with these elements immobilized on microspheres (beads). The possibility of rapid detection of multiple antibodies simultaneously, with a small sample volume and high sensitivity and specificity, makes flow cytometry a promising methodology for the clinical laboratory, as a reference tool to help stop the COVID-19 pandemic process and similar future events.


Assuntos
Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Citometria de Fluxo , SARS-CoV-2 , COVID-19
12.
Sci Rep ; 11(1): 1788, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469044

RESUMO

The ATP-binding cassette transporter ABCG2 mediates the efflux of several chemotherapeutic drugs, contributing to the development of multidrug resistance (MDR) in many cancers. The most promising strategy to overcome ABCG2-mediated MDR is the use of specific inhibitors. Despite many efforts, the identification of new potent and specific ABCG2 inhibitors remains urgent. In this study, a structural optimization of indeno[1,2-b]indole was performed and a new generation of 18 compounds was synthesized and tested as ABCG2 inhibitors. Most compounds showed ABCG2 inhibition with IC50 values below 0.5 µM. The ratio between cytotoxicity (IG50) and ABCG2 inhibition potency (IC50) was used to identify the best inhibitors. In addition, it was observed that some indeno[1,2-b]indole derivatives produced complete inhibition, while others only partially inhibited the transport function of ABCG2. All indeno[1,2-b]indole derivatives are not transported by ABCG2, and even the partial inhibitors are able to fully chemosensitize cancer cells overexpressing ABCG2. The high affinity of these indeno[1,2-b]indole derivatives was confirmed by the strong stimulatory effect on ABCG2 ATPase activity. These compounds did not affect the binding of conformation-sensitive antibody 5D3 binding, but stabilized the protein structure, as revealed by the thermostabilization assay. Finally, a docking study showed the indeno[1,2-b]indole derivatives share the same binding site as the substrate estrone-3-sulfate.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Neoplasias da Mama/metabolismo , Indóis/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Indóis/química , Relação Estrutura-Atividade
13.
Braz. J. Pharm. Sci. (Online) ; 57: e19078, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345449

RESUMO

1,5-Anhydroglucitol (1,5-AG) is a non-fasting glycemic marker that responds to hyperglycemia excursions. The reduction in serum levels of 1,5-AG is associated with an increase in postprandial glycemia and glycosuria, phenomena that increase the risk and severity of diabetic complications. The objective is to assess the ability of 1,5-AG to discriminate type 2 diabetes (T2D) patients without overt kidney disease, for screening or diagnostic purposes. The Human Research Ethics Committee of Universidade Federal do Paraná (UFPR) approved the project. Serum samples from 567 individuals classified as healthy subjects (n = 291) and T2D (n = 276) with moderate glycemic control (HbA1c of 7-8%), matched by gender, were analyzed. Serum 1,5-AG levels were measured using an automated enzymatic method (GlycoMark, Inc.). Receiver Operating Characteristic (ROC) curve analysis for 1,5-AG showed sensibility of 65.3% and specificity of 91.1% to detect T2D at cut-off point of 92 µmol/L. The results were similar to the groups' discrimination by glycemia (sensibility/specificity, 62.2%; 89.0%) at cut-off point of 6.3 mmol/L. HbA1c was the best discriminator (sensibility/specificity, 87.4%; 94.2%) at a cut-off point of 5.8% (40 mmol/mol). The serum 1,5-AG concentration was not able to discriminate T2D in the presence of moderate glycemic control with no overt nephropathy.


Assuntos
Humanos , Masculino , Feminino , Pacientes/classificação , Curva ROC , Diabetes Mellitus Tipo 2/patologia , Biomarcadores , Complicações do Diabetes , Controle Glicêmico/instrumentação , Hiperglicemia/complicações
14.
Rev. bras. anal. clin ; 52(4): 337-345, 20201230. tab, ilus
Artigo em Português | LILACS | ID: biblio-1223688

RESUMO

Em humanos, o pH sanguíneo é mantido em uma faixa estreita, entre 7,35 e 7,45. Diferentes mecanismos bioquímicos, de forma harmônica, atuam para a manutenção do pH fisiológico. Múltiplos processos patológicos podem promover alterações no pH e nos gases sanguíneos, caracterizando acidose (pH <7,35) ou alcalose (pH >7,45). A ruptura da homeostasia do pH é identificada pela medição do pH, pressão parcial de dióxido de carbono (pCO2), concentração do bicarbonato (HCO3-) e, adicionalmente, com a pressão de oxigênio (pO2) em sangue arterial, processo descrito como gasometria arterial. Este artigo revisa os principais elementos associados a compreensão das alterações e tem como objetivo central apresentar uma abordagem didática e intuitiva para a caracterização destes distúrbios; e também comenta sobre ferramentais digitais destinadas a interpretações das alterações da gasometria arterial que também são abordados, como programas para computadores em ambiente web e aplicativos para telefonia móvel.


In humans, blood pH is kept in a narrow range, between 7.35 to 7.45. Different biochemical mechanisms, in a harmonic way, act to maintain the physiological pH. Multiple pathological processes can promote changes in pH and blood gases, characterizing acidosis (pH <7.35) or alkalosis (pH> 7.45). The rupture of pH homeostasis is identified by measuring pH, partial pressure of carbon dioxide (pCO2), bicarbonate concentration (HCO3 - and, in addition, with the pressure of oxygen (pO2) in arterial blood, a process described as gasometry arterial. This article reviews the main elements associated with the understanding of acid-base changes and aims to present a didactic and intuitive approach to the characterization of these disorders; and also comments on digital tools for the interpretation of alterations in arterial blood gases are also covered, such as programs for computers in a web environment and applications for mobile phone.


Assuntos
Valores de Referência , Desequilíbrio Ácido-Base , Gasometria , Software , Aplicativos Móveis
15.
Rev. bras. anal. clin ; 52(2): 154-159, 20200630.
Artigo em Português | LILACS | ID: biblio-1147061

RESUMO

O mundo enfrenta duas pandemias distintas, mas que guardam alguma relação entre si. O Diabetes mellitus (DM) promove um estado crônico inflamatório que torna os afetados mais propensos a infecções em geral. A doença aguda causada pelo novo coronavírus, COVID-19, assim como o DM, altera o sistema imunológico, podendo ativar uma tempestade de citocinas deletéria ao hospedeiro. O DM tem sido considerado como um fator de risco independente da idade para a gravidade da COVID-19. De fato, pessoas com DM são propensas a um curso clínico de maior severidade da COVID-19 com maior taxa de morbimortalidade. Uma forte relação entre a COVID-19 e o DM reside no fato de que o SARS-CoV-2 utiliza a proteína ACE-2 como receptor para entrar na célula humana, a qual é superexpressa pelas células das ilhotas pancreáticas e ainda mais em pessoas com DM. Depois de invadir a célula do hospedeiro, o vírus degrada a ACE-2, reduzindo sua atividade anti-inflamatória. Somado a isso, acredita-se que o SARS-CoV-2 afete diretamente a parte endócrina do pâncreas, com consequente hiperglicemia. Entretanto, ainda não está claro de que forma as alterações glicêmicas podem estar relacionadas com a severidade da COVID-19; e se o SARS-CoV-2 tem potencial diabetogênico. Todavia, os mecanismos propostos para explicar a associação observada entre DM e a COVID-19 incluem inflamação, alterações na resposta imune, na coagulação e a agressão direta do vírus às células b pancreáticas. Como o diabetes está associado às manifestações graves da COVID-19, o primeiro passo é evitar a contaminação de pessoas com DM pelo SARS-CoV-2. Depois, todo paciente com COVID-19 que tenha DM deve ser considerado grave. E, por fim, a monitoração glicêmica frequente em pacientes com COVID-19 deve ser considerada, uma vez que o controle da hiperglicemia tem se mostrado eficaz na promoção de melhores desfechos clínicos.


The world faces two distinct pandemics, which have some relationship with each other. Diabetes mellitus (DM) promotes a chronic inflammatory state that makes the affected more prone to general infections. The acute disease caused by the new coronavirus, COVID19, as well as DM, alters the immune system, which can activate a harmful cytokine storm in the host. DM has been considered as an age-independent risk factor for the severity of COVID-19. In fact, people with DM are prone to a more severe clinical course of COVID19 with a higher rate of morbidity and mortality. A strong relationship between COVID-19 and DM lies in the fact that SARS-CoV-2 uses the ACE-2 protein as a receptor to enter the human cell, which is overexpressed by pancreatic islet cells, especially in people with DM. After invading the host cell, the virus degrades ACE-2, reducing its anti-inflammatory activity. In addition, SARS-CoV-2 is believed to directly affect the endocrine part of the pancreas, with consequent hyperglycemia. However, it is not clear how glycemic changes may be related to the severity of COVID-19; and, whether SARS-CoV-2 has diabetogenic potential. However, the mechanisms proposed to explain the observed association between DM and COVID-19 include inflammation, changes in the immune response, coagulation and direct aggression of the virus to pancreatic beta cells. As diabetes is associated with severe manifestations of COVID-19, the first step is to avoid contamination of people with DM by SARS-CoV-2. Then, every patient with COVID-19 who has DM should be considered severe. Finally, frequent glycemic monitoring in patients with COVID-19 should be considered, since the control of hyperglycemia has been shown to be effective in promoting better clinical outcomes


Assuntos
Infecções por Coronavirus , Diabetes Mellitus
16.
Arch. endocrinol. metab. (Online) ; 63(5): 524-530, Sept.-Oct. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1038503

RESUMO

ABSTRACT Objective The aim of the study is to describe a portable and convenient software to facilitate the diagnostics of gestational (GDM) and pre-gestational diabetes (PGDM). Materials and methods An open source software, d-GDM, was developed in Java. The integrated development environment Android Studio was used as the Android operational system. The software for GDM diagnosis uses the criteria endorsed by the International Association of Diabetes and Pregnancy Study Group, modified by the World Health Organization. Results GDM diagnosis criteria is not simple to follow, therefore, errors or inconsistencies in diagnosis are expected and could delay the appropriate treatment. The d-GDM, was developed to assist GDM diagnosis with precision and consistency diagnostic reports. The open source software can be manipulated conveniently. The operator requires information regarding the gestational period and selects the appropriate glycaemic marker options from the menu. During operation, pressing the button "diagnosticar" on the screen will present the diagnosis and information for the follow up. d-GDM is available in Portuguese or English and can be downloaded from the Google PlayStore. A responsive web version of d-GDM is also available. The usefulness and accuracy of d-GDM was verify by field tests involving 22 subjects and 5 mobile phone brands. The approval regards user-friendliness and efficiency were 95% or higher. The GDM diagnosis were 100% correct, in this pilot test. d-GDM is a user-friendly, free software for diagnosis that was developed for mobile devices. It has the potential to contribute and facilitate the diagnosis of gestational diabetes for healthcare professionals.


Assuntos
Humanos , Feminino , Gravidez , Técnicas de Apoio para a Decisão , Diabetes Gestacional/diagnóstico , Aplicativos Móveis
17.
Arch Endocrinol Metab ; 63(5): 524-530, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482958

RESUMO

OBJECTIVE: The aim of the study is to describe a portable and convenient software to facilitate the diagnostics of gestational (GDM) and pre-gestational diabetes (PGDM). MATERIALS AND METHODS: An open source software, d-GDM, was developed in Java. The integrated development environment Android Studio was used as the Android operational system. The software for GDM diagnosis uses the criteria endorsed by the International Association of Diabetes and Pregnancy Study Group, modified by the World Health Organization. RESULTS: GDM diagnosis criteria is not simple to follow, therefore, errors or inconsistencies in diagnosis are expected and could delay the appropriate treatment. The d-GDM, was developed to assist GDM diagnosis with precision and consistency diagnostic reports. The open source software can be manipulated conveniently. The operator requires information regarding the gestational period and selects the appropriate glycaemic marker options from the menu. During operation, pressing the button "diagnosticar" on the screen will present the diagnosis and information for the follow up. d-GDM is available in Portuguese or English and can be downloaded from the Google PlayStore. A responsive web version of d-GDM is also available. The usefulness and accuracy of d-GDM was verify by field tests involving 22 subjects and 5 mobile phone brands. The approval regards user-friendliness and efficiency were 95% or higher. The GDM diagnosis were 100% correct, in this pilot test. d-GDM is a user-friendly, free software for diagnosis that was developed for mobile devices. It has the potential to contribute and facilitate the diagnosis of gestational diabetes for healthcare professionals.


Assuntos
Técnicas de Apoio para a Decisão , Diabetes Gestacional/diagnóstico , Aplicativos Móveis , Feminino , Humanos , Gravidez
18.
Clin Lab ; 65(9)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31532108

RESUMO

BACKGROUND: Type 1 diabetes (T1D) is an autoimmune disease and the leading form of diabetes among young white people. 1,5-Anhydroglucitol (1,5-AG), a nontraditional biomarker of postprandial glycemic control (after 1 - 3 days to 2 weeks), may be useful in T1D screening. We studied serum 1,5-AG concentration as a potential biomarker for T1D screening and diagnosis in adults and children. METHODS: In this case-control study, adults (n = 121; age, 19 - 61 years) and children (n = 19; age, 8 - 14 years) with T1D were matched with healthy subjects (n = 242) according to gender and age. Serum 1,5-AG levels were measured enzymatically (GlycoMark Inc., NY, USA). RESULTS: Patients showed no symptoms of overt kidney disease, assessed by serum creatinine concentrations. The median (25th - 75th percentile) 1,5-AG concentrations for the control group compared with the T1D group were 155 (128 - 183) vs. 21 (14 - 34) µmol/L in adults and 190 (158 - 237) vs. 20 (12 - 30) µmol/L in children (p < 0.001 for both). Receiver operating characteristic curves showed that 1,5-AG cutoffs of ≤ 113 and ≤ 79 µmol/L for adult men and women, respectively, and ≤ 57 µmol/L for children of both genders had > 95% sensitivity and specificity for both groups. CONCLUSIONS: Our results suggest that serum 1,5-AG concentration may be useful as an adjunct measure of hyperglycemia for diagnosing T1D and has the potential to screen for T1D in high-risk subjects.


Assuntos
Biomarcadores/sangue , Desoxiglucose/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Creatinina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco , Adulto Jovem
19.
Rev. bras. anal. clin ; 50(4): 358-364, 20190410. Graf.
Artigo em Português | LILACS | ID: biblio-995989

RESUMO

Os procedimentos de rotina para avaliação do controle glicêmico em indivíduos com diabetes mellitus (DM) são a glicemia de jejum, que reflete a concentração glicêmica no momento do teste, e a hemoglobina glicada (A1C), que traduz a glicemia dos últimos quatro meses. Recentemente tem sido recomendado o cálculo da glicemia média estimada (GME) para avaliar o controle glicêmico, pela equação GME (mg/dL) = 28,7 × HbA1C ­ 46,7. A GME é mais simples de ser interpretada pelo diabético, facilitando a compreensão do seu estado glicêmico. Neste estudo avaliamos a relação da GME com os valores da glicemia em jejum. Foram estudados 49 diabéticos (grupo DM) com três coletas de sangue cada, a intervalos de 120 dias entre as coletas, e 30 indivíduos sadios (grupo controle). As médias das três determinações de glicemia em jejum e A1C do grupo DM foram utilizadas para as análises. Os valores médios de glicemia em jejum (mg/dL), A1C (%) e GME (mg/dL) para os grupos DM e controle foram, respectivamente: 163,55, 8,38 e 193,83; e 71,0, 5,14 e 100,91. A fórmula não traz benefícios para indivíduos não diabéticos, pois superestima os valores de glicemia. Os resultados da glicemia em jejum e GME do grupo DM foram diferentes (P<0,001, Wilcoxon), com correlação (r) de 0,83 (p<0,001). Portanto, a GME tem boa correlação com a glicemia de jejum, mas seus valores podem diferir pelo fato de a GME refletir a A1C, um marcador glicêmico de longo prazo.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Glicemia , Hemoglobinas Glicadas
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