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1.
Biochem Med (Zagreb) ; 29(3): 030701, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31379459

RESUMO

Introduction: Complement functional analyses provide insight into the integrity of the entire complement reaction cascade. These tests are suitable for investigating suspected complement deficiencies. Falsely reduced test outcomes may result from preanalytical instabilities of individual complement components. To generate rationale for this or potential alternative practices, this study aimed to extend the knowledge on the preanalytical stability of widely used tests to screen the complement system. We assessed the influence of time, temperature and EDTA on classical (CH50) and alternative pathway (AP50) functional assay test results. Materials and methods: We used nephelometric (C3d) and immunofixation (C3c) techniques to support the investigation of the preanalytical phase of basic complement system activity tests. Quantitative determination of classical and alternative pathway function was performed with a haemolytic activity assay and a C5b-9 neo-epitope ELISA-based assay respectively. Blood of five healthy volunteers was sampled and complement components allowed to degrade under different conditions. Results: CH50 and AP50 remain stable for approximately one week in serum samples incubated on ice. CH50 activity decreased almost twice as fast in EDTA plasma compared to serum at room temperature. AP50 activity contrastingly, decreased twice as slow in EDTA plasma compared to serum at room temperature. Conclusion: Serum on ice remains the preferred specimen for functional complement analyses. In the absence of serum transported on ice, serum kept at room temperature (not exceeding 24h) is suitable for classical and alternative pathway analyses. For alternative pathway analyses specifically, the C3-stabilising effect of EDTA allows for the extended use of EDTA plasma (not over 4 days). In these conditions, at least 85% of baseline complement activity remains.


Assuntos
Via Alternativa do Complemento , Via Clássica do Complemento , Fase Pré-Analítica/normas , Complemento C3/análise , Complexo de Ataque à Membrana do Sistema Complemento/análise , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Ensaio de Imunoadsorção Enzimática , Hemólise , Humanos , Soro/química , Temperatura Ambiente
3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1215-1219, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418382

RESUMO

OBJECTIVE: To evaluate the clinical efficacy of low dose combined chemotherapy(LDCC) for patients with relapsed and refractory aplastic anemia-paroxysmal nocturnal hemoglobinuria(AA-PNH) syndrome, and to analyze the advantages of LDCC in the treatment of AA-PNH syndrome. METHODS: The clinical characteristics and the curative effect of LDCC in 9 patients with relapsed and refractory AA-PNH syndrome were retrospectively analyzed. Five patients were treated with MP therapyï¼»melphalan 2 mg/(m2·d); prednisone 0.5 mg/(kg·d)ï¼½, and the other 4 patients were treated with HA therapy(HHT 2 mg/d iv drip, for 5 days; Ara-C 100 mg/d iv drip, for 5 days). The changes of PNH clone, dosage of corticosteroid, hemolysis and the relapse of disease, hematological parameters and adverse reactions were compared before and after therapy. All patients were treated for 1-2 courses. RESULTS: Seven out of 9 patients responded well, the dosage of corticosteroid and the bilirubin concentration decreased significantly and anemia was relieved in 7 patients (P<0.05). One patient relapsed in one year. PNH clone of 3 patients turned negative. Five patients did not rely on blood transfusion in 1 year. There was no bone marrow failure to be found in all patients. CONCLUSION: The LDCC has better efficacy and safety in the treatment of patients with AA-PNH syndrome, moreover, the patients is more tolerant to LDCC, thus the LDCC may be a selection for treatment of patients with relapsed and refractory AA-PNH syndrome.


Assuntos
Anemia Aplástica , Anemia Refratária , Hemoglobinúria Paroxística , Hemólise , Humanos , Estudos Retrospectivos
4.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
5.
Bol. latinoam. Caribe plantas med. aromát ; 18(4): 359-377, jul. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1008174

RESUMO

Plant species have been used for therapeutic purposes since ancient times and are still in use today since these products represent a source of raw material for the production of phytotherapeutic formulations. Screening and investigation of plants with pharmacological potential require the evaluation of characteristics related to their action, efficacy and safety in different steps. Among these steps, pre- clinical trials are used to evaluate the properties of the test product in in vitro experiments, such as cytotoxicity assays. Within this context, this study consists of a bibliometric analysis of some in vitro cytotoxicity and toxicity assays in erythrocytes used during bioprospecting of medicinal plants. The results demonstrated the wide application of erythrocytes to evaluate the biological effects of medicinal plant extracts. The methods were found to be valid and effective for the preliminary investigation of the in vitro cytotoxicity and toxicity of plant products.


El uso de especies vegetales para fines terapéuticos es una práctica histórica y todavía bastante actual, ya que estos productos pueden representar una fuente de materia prima para la producción de formulaciones fitoterápicas. En investigación de plantas con potencial farmacológico requiere la evaluación de su acción, eficacia y seguridad, a través de diferentes etapas. Entre estas, en los ensayos preclínicos se evalúan las propiedades del producto-prueba en experimentos in vitro, tales como ensayos de citotoxicidad, entre otros. En este aspecto, el presente estudio consiste en un análisis bibliométrico acerca de algunas pruebas de citotoxicidad y toxicidad in vitro en eritrocitos realizados en los ensayos de bioprospección de plantas medicinales. Los resultados evidencian la amplia utilización de eritrocitos para la evaluación de los efectos biológicos de extractos de plantas medicinales, apuntándolos como métodos válidos y eficaces para la investigación preliminar de la citotoxicidad y toxicidad in vitro de productos vegetales.


Assuntos
Bioensaio/métodos , Extratos Vegetais/toxicidade , Eritrócitos/efeitos dos fármacos , Antioxidantes/toxicidade , Fragilidade Osmótica , Estresse Oxidativo , Eritrócitos/citologia , Bioprospecção , Hemólise/efeitos dos fármacos
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(3): 887-892, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31204949

RESUMO

OBJECTIVE: To establish the model of antibody-induced immune hemolytic disease in SD rats so as to provide an experimental platform for the exploration of its pathogenesis, course of disease and evaluation of drug efficacy. METHODS: The red blood cells(RBC) of SD rats were isolated and intraperitoneally injected into BALB/c mice to induce production of the antiserum to SD rat RBC. Twenty SD rats were randomly divided into 2 groups. The rats in the model group were injected with 0.1 ml antiserum via tail vein; the rats in the control group were injected with 0.1 ml saline via tail vein.The symptoms of rats, hemolysis-related indexes and histopathological changes of the main organs were observed in both groups after injection. RESULTS: After the injection of antiserum, the SD rats in the model group displayed nasal flaring, laziness, decrease of ingestion and water intake, skin and mucosal jaundice, and gross hemoglobinuria. At the 4th day after the injection, the body weight of SD rats in the model group was significantly lower than that in the control group (P<0.01), and the coefficiens of liver and spleen increased significantly (P<0.01); The levels of WBC, MCV, MCH, DBIL, DBIL/TBIL and FHb all increased statistically significantly, and RBC, Hb, HCT, MCHC and Plt levels decreased significantly in comparison with the control group (P<0.01). In the SD rats of model group, the hemolytic pathological changes were observed in liver, spleen, kidney, lung and small intestine, and erythroid proliferation was observed in bone marrow smears. CONCLUSION: The immune hemolytic disease model of SD rats can be successfully established by injecting the serum aginst SD rat red blood cells into the tail vein of SD rats, showing the high success rate, good reproducibility and low cost.


Assuntos
Hemólise , Fígado , Animais , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
8.
Niger Postgrad Med J ; 26(2): 118-122, 2019 Apr-Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31187752

RESUMO

Background: Sickle cell disease (SCD) and glucose-6-phosphate dehydrogenase (G6PD) deficiency are inherited disorders associated with chronic haemolysis. Therefore, coinheritance of both disorders could worsen haemolysis in the former and compound a haemolytic crisis. This study compared clinical and laboratory features of deficient and non-deficient SCD patients and the G6PD activities of SCD patients and apparently healthy controls. Materials and Methods: This is a case-control study of 175 SCD patients and 166 non-SCD controls. G6PD assay was carried out on haemolysate from washed red cells. The G6PD activity was measured by spectrophotometry. Results: The mean age of patients and controls was 27.3 ± 9.4 and 35.9 ± 9.7 years, respectively, with 75 (46.2%) and 87 (52.4%) being males, respectively. G6PD activity was similar in cases and controls (6.7 ± 3.3 vs. 6.9 ± 3.0 IU/gHb), respectively (P = 0.6). The prevalence of G6PD deficiency was higher in patients than controls (28.6% vs. 22.3%, P = 0.18), and SCD patients were twice more likely to have enzyme activities below 3.0 IU/gHb. No significant difference was observed in the clinical parameters between deficient and non-deficient patients. Deficient patients were more likely to have lower haematocrit (22.8 ± 3.9% vs. 24.5 ± 5%, P = 0.04) and non-significantly higher bilirubin and reticulocyte counts. Furthermore, in patients, severe deficiency resulted in higher bilirubin than in those with mild deficiency (60.5 vs. 21.7 IU/L, P < 0.001). G6PD activity correlated positively with haematocrit (r = 0.91, P = 0.01) and mean corpuscular haemoglobin concentration (r = 0.17, P = 0.02). Conclusions: Coinheritance of both disorders could worsen haemolysis in SCD patients, and care should, therefore, be taken in the choice of drugs in deficient SCD patients.


Assuntos
Anemia Falciforme/complicações , Anemia Falciforme/genética , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , Hemólise/genética , Adolescente , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/epidemiologia , Bilirrubina/sangue , Estudos de Casos e Controles , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/sangue , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Hemoglobinas/análise , Humanos , Masculino , Nigéria/epidemiologia , Prevalência , Adulto Jovem
9.
Eur J Med Chem ; 178: 214-231, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31185412

RESUMO

Discovery of antimicrobial agents with a novel model of action is in urgent need for the clinical management of multidrug-resistant bacterial infections. Recently, we reported the identification of a first-in-class bacterial ribosomal RNA synthesis inhibitor, which interrupted the interaction between the bacterial transcription factor NusB and NusE. In this study, a series of diaryl derivatives were rationally designed and synthesized based on the previously established pharmacophore model. Inhibitory activity against the NusB-NusE binding, circular dichroism of compound treated NusB, antimicrobial activity, cytotoxicity, hemolytic property and cell permeability using Caco-2 cells were measured. Structure-activity relationship and quantitative structure-activity relationship were also concluded and discussed. Some of the derivatives demonstrated improved antimicrobial activity than the hit compound against a panel of clinically important pathogens, lowering the minimum inhibition concentration to 1-2 µg/mL against Staphylococcus aureus, including clinical strains of methicillin-resistant Staphylococcus aureus at a level comparable to some of the marketed antibiotics. Given the improved antimicrobial activity, specific inhibition of target protein-protein interaction and promising pharmacokinetic properties without significant cytotoxicity, this series of diaryl compounds have high potentials and deserve for further studies towards a new class of antimicrobial agents in the future.


Assuntos
Compostos de Anilina/farmacologia , Antibacterianos/farmacologia , Benzilaminas/farmacologia , Ligação Proteica/efeitos dos fármacos , Bases de Schiff/farmacologia , Compostos de Anilina/síntese química , Compostos de Anilina/química , Compostos de Anilina/toxicidade , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Proteínas de Bactérias/metabolismo , Benzilaminas/síntese química , Benzilaminas/química , Benzilaminas/toxicidade , Células CACO-2 , Desenho de Drogas , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Bases de Schiff/síntese química , Bases de Schiff/química , Bases de Schiff/toxicidade , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
10.
Biochem Med (Zagreb) ; 29(2): 020705, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31223259

RESUMO

Introduction: No guideline currently exists on how to detect or document haemolysis, icterus or lipemia (HIL) in blood samples, nor on subsequent use of this information. The EFLM WG-PRE has performed a survey for assessing current practices of European laboratories in HIL monitoring. This second part of two coherent articles is focused on HIL. Materials and methods: An online survey, containing 39 questions on preanalytical issues, was disseminated among EFLM member countries. Seventeen questions exclusively focused on assessment, management and follow-up actions of HIL in routine blood samples. Results: Overall, 1405 valid responses from 37 countries were received. A total of 1160 (86%) of all responders stating to analyse blood samples - monitored HIL. HIL was mostly checked in clinical chemistry samples and less frequently in those received for coagulation, therapeutic drug monitoring and serology/infectious disease testing. HIL detection by automatic HIL indices or visual inspection, along with haemolysis cut-offs definition, varied widely among responders. A quarter of responders performing automated HIL checks used internal quality controls. In haemolytic/icteric/lipemic samples, most responders (70%) only rejected HIL-sensitive parameters, whilst about 20% released all test results with general comments. Other responders did not analysed but rejected the entire sample, while some released all tests, without comments. Overall, 26% responders who monitored HIL were using this information for monitoring phlebotomy or sample transport quality. Conclusion: Strategies for monitoring and treating haemolytic, icteric or lipemic samples are quite heterogeneous in Europe. The WG-PRE will use these insights for developing and providing recommendations aimed at harmonizing strategies across Europe.


Assuntos
Medicina Clínica , Hemólise , Hiperlipidemias/sangue , Icterícia/sangue , Fase Pré-Analítica , Inquéritos e Questionários , Química Clínica , Técnicas de Laboratório Clínico , Europa (Continente) , Humanos
11.
Nat Commun ; 10(1): 2702, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221991

RESUMO

Most cationic vectors are difficult to avoid the fate of small interfering RNA (siRNA) degradation following the endosome-lysosome pathway during siRNA transfection. In this study, the endoplasmic reticulum (ER) membrane isolated from cancer cells was used to fabricate an integrative hybrid nanoplexes (EhCv/siRNA NPs) for improving siRNA transfection. Compared to the undecorated Cv/siEGFR NPs, the ER membrane-decorated EhCv/siRNA NPs exhibits a significantly higher gene silencing effect of siRNA in vitro and a better antitumor activity in nude mice bearing MCF-7 human breast tumor in vivo. Further mechanistic studies demonstrate that functional proteins on the ER membrane plays important roles on improving cellular uptake and altering intracellular trafficking pathway of siRNA. It is worth to believe that the ER membrane decoration on nanoplexes can effectively transport siRNA through the endosome-Golgi-ER pathway to evade lysosomal degradation and enhance the silencing effects of siRNA.


Assuntos
Portadores de Fármacos/química , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Transfecção/métodos , Animais , Linhagem Celular Tumoral , Membrana Celular , Portadores de Fármacos/efeitos adversos , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Receptores ErbB/genética , Feminino , Terapia Genética/métodos , Complexo de Golgi/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/química , Neoplasias/genética , Neoplasias/terapia , RNA Interferente Pequeno/efeitos adversos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Agric Food Chem ; 67(27): 7650-7659, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31241944

RESUMO

Neutrase-hydrolysates hydrolyzed from mulberry leaf proteins were separated by ion exchange chromatography, gel filtration chromatography, and semipreparative reverse-phase HPLC. Purified fractions were analyzed for their radical scavenging activity, hemolysis inhibition ability, and cellular antioxidant activity (CAA). Three new antioxidant peptides, P1 (SVL, 317 Da), P2 (EAVQ, 445 Da), and P3 (RDY, 452 Da), were obtained from the most active HPLC fraction (R1) and identified using UPLC-QTOF-MS. These three peptides were then synthesized, and their antioxidant activities were analyzed. P1 and P2 had no ability to inhibit hemolysis of erythrocytes but did show antioxidant activity on HepG2 cells. P3 showed the highest hemolysis inhibition ability (92%) and CAA value (2204 µM QE/100 g peptide). The Tyr residues at the C-terminal region play an important role in the antioxidant activity in P3. Thus, the natural peptide R1 and synthesized P3 could be used as antioxidants and might be promising components of functional foods.


Assuntos
Antioxidantes/farmacologia , Hemólise/efeitos dos fármacos , Morus/química , Peptídeos/farmacologia , Folhas de Planta/química , Proteínas de Plantas/metabolismo , Cromatografia Líquida de Alta Pressão , Células Hep G2 , Humanos , Hidrólise , Fígado/efeitos dos fármacos , Metaloendopeptidases/metabolismo , Peso Molecular , Peptídeos/química , Peptídeos/isolamento & purificação
13.
Ann Hematol ; 98(9): 2045-2052, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31243572

RESUMO

Thalassemia has a high prevalence in Thailand. Oxidative damage to erythroid cells is known to be one of the major etiologies in thalassemia pathophysiology. Oxidative stress status of thalassemia is potentiated by the heme, nonheme iron, and free iron resulting from imbalanced globin synthesis. In addition, levels of antioxidant proteins are reduced in α-thalassemia and ß-thalassemia erythrocytes. However, the primary molecular mechanism for this phenotype remains unknown. Our study showed a high expression of miR-144 in ß- and α-thalassemia. An increased miR-144 expression leads to decreased expression of nuclear factor erythroid 2-related factor 2 (NRF2) target, especially in α-thalassemia. In α-thalassemia, miR-144 and NRF2 target are associated with glutathione level and anemia severity. To study the effect of miR-144 expression, the gain-loss of miR-144 expression was performed by miR inhibitor and mimic transfection in the erythroblastic cell line. This study reveals that miR-144 expression was upregulated, whereas NRF2 expression and glutathione levels were decreased in comparison with the untreated condition after miR mimic transfection, while the reduction of miR-144 expression contributed to the increased NRF2 expression and glutathione level compared with the untreated condition after miR inhibitor transfection. Moreover, miR-144 overexpression leads to significantly increased sensitivity to oxidative stress at indicated concentrations of hydrogen peroxide (H2O2) and rescued by miR-144 inhibitor. Taken together, our findings suggest that dysregulation of miR-144 may play a role in the reduced ability of erythrocyte to deal with oxidative stress and increased RBC hemolysis susceptibility especially in thalassemia.


Assuntos
Eritrócitos/metabolismo , MicroRNAs/biossíntese , Fator 2 Relacionado a NF-E2/biossíntese , Estresse Oxidativo , Regulação para Cima , Talassemia alfa/metabolismo , Talassemia beta/metabolismo , Eritrócitos/patologia , Feminino , Glutationa/biossíntese , Glutationa/genética , Hemólise , Humanos , Peróxido de Hidrogênio/metabolismo , Células K562 , Masculino , MicroRNAs/genética , Fator 2 Relacionado a NF-E2/genética , Talassemia alfa/genética , Talassemia alfa/patologia , Talassemia beta/genética , Talassemia beta/patologia
14.
Klin Lab Diagn ; 64(5): 294-298, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31185153

RESUMO

Clinical strains of Staphylococcus aureus were tested for hemolytic activity on blood agar, in the PCR test and by analyzing the gene alleles of hemolytic toxins. The study analyzed the information content of the phenotypic determination of hemolytic activity to assess the pathogenic properties of S. aureus isolates.


Assuntos
Toxinas Bacterianas/genética , Hemólise , Staphylococcus aureus/patogenicidade , Humanos , Federação Russa , Infecções Estafilocócicas , Staphylococcus aureus/genética
15.
N Engl J Med ; 381(6): 509-519, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31199090

RESUMO

BACKGROUND: Deoxygenated sickle hemoglobin (HbS) polymerization drives the pathophysiology of sickle cell disease. Therefore, direct inhibition of HbS polymerization has potential to favorably modify disease outcomes. Voxelotor is an HbS polymerization inhibitor. METHODS: In a multicenter, phase 3, double-blind, randomized, placebo-controlled trial, we compared the efficacy and safety of two dose levels of voxelotor (1500 mg and 900 mg, administered orally once daily) with placebo in persons with sickle cell disease. The primary end point was the percentage of participants who had a hemoglobin response, which was defined as an increase of more than 1.0 g per deciliter from baseline at week 24 in the intention-to-treat analysis. RESULTS: A total of 274 participants were randomly assigned in a 1:1:1 ratio to receive a once-daily oral dose of 1500 mg of voxelotor, 900 mg of voxelotor, or placebo. Most participants had sickle cell anemia (homozygous hemoglobin S or hemoglobin Sß0-thalassemia), and approximately two thirds were receiving hydroxyurea at baseline. In the intention-to-treat analysis, a significantly higher percentage of participants had a hemoglobin response in the 1500-mg voxelotor group (51%; 95% confidence interval [CI], 41 to 61) than in the placebo group (7%; 95% CI, 1 to 12). Anemia worsened between baseline and week 24 in fewer participants in each voxelotor dose group than in those receiving placebo. At week 24, the 1500-mg voxelotor group had significantly greater reductions from baseline in the indirect bilirubin level and percentage of reticulocytes than the placebo group. The percentage of participants with an adverse event that occurred or worsened during the treatment period was similar across the trial groups. Adverse events of at least grade 3 occurred in 26% of the participants in the 1500-mg voxelotor group, 23% in the 900-mg voxelotor group, and 26% in the placebo group. Most adverse events were not related to the trial drug or placebo, as determined by the investigators. CONCLUSIONS: In this phase 3 randomized, placebo-controlled trial involving participants with sickle cell disease, voxelotor significantly increased hemoglobin levels and reduced markers of hemolysis. These findings are consistent with inhibition of HbS polymerization and indicate a disease-modifying potential. (Funded by Global Blood Therapeutics; HOPE ClinicalTrials.gov number, NCT03036813.).


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/administração & dosagem , Benzaldeídos/administração & dosagem , Hemoglobina Falciforme/efeitos dos fármacos , Hemoglobinas/metabolismo , Pirazinas/administração & dosagem , Pirazóis/administração & dosagem , Adolescente , Adulto , Anemia Falciforme/sangue , Antidrepanocíticos/efeitos adversos , Antidrepanocíticos/uso terapêutico , Benzaldeídos/efeitos adversos , Biomarcadores/sangue , Criança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hemoglobina Falciforme/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Hidroxiureia/uso terapêutico , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Polimerização/efeitos dos fármacos , Pirazinas/efeitos adversos , Pirazóis/efeitos adversos , Adulto Jovem
16.
Ann Hematol ; 98(7): 1583-1592, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31041514

RESUMO

Despite the advances in the management of hemoglobinopathies, further insight into disease pathophysiology is necessary to improve our therapeutic approach. Activin-A has emerged as a regulator of erythropoiesis and bone turnover in malignant disorders; however, clinical data in hemoglobinopathies are currently scarce. Thus, we aimed to investigate the role of activin-A among hemoglobinopathy patients and evaluate the rationale of its targeting. Circulating levels of activin-A were measured in patients (n = 227) with beta-thalassemia major (TM) (n = 58), beta-thalassemia intermedia (TI) (n = 43), double heterozygous sickle cell/beta-thalassemia (HbS/beta-thal) (n = 109), or homozygous sickle cell disease (n = 17), and we explored possible correlations with clinical and laboratory data. Seventeen age- and gender-matched, healthy individuals served as controls. Bone marrow density (BMD) was determined using dual-energy X-ray absorptiometry. TM and HbS/beta-thal patients had elevated activin-A compared to controls (p = 0.041 and p = 0.038, respectively). In TM patients, high circulating activin-A showed strong correlations with hemolysis markers, namely reticulocyte count (p = 0.011) and high lactate dehydrogenase (LDH; p = 0.024). Similarly, in HbS/beta-thal patients, activin-A showed positive correlations with indirect bilirubin (p < 0.001), ferritin (p = 0.005), and LDH (p = 0.044). High activin-A correlated with low Z-score of both lumbar spine BMD in TI patients (p < 0.01) and femoral neck BMD in TM patients (p < 0.01). Serum activin-A is elevated in patients with TM and HbS/beta-thal and correlates with markers of hemolysis and low BMD. These data support a role of activin-A in the biology of these disorders and provide further rationale for the broader clinical development of activin-A inhibitors in this setting.


Assuntos
Ativinas/sangue , Anemia Falciforme , Densidade Óssea , Hemólise , Heterozigoto , Talassemia beta , Ativinas/genética , Adulto , Idoso , Anemia Falciforme/sangue , Anemia Falciforme/genética , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Reticulócitos , Talassemia beta/sangue , Talassemia beta/genética
17.
Anaesthesia ; 74(8): 1026-1032, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31062351

RESUMO

Pre-hospital transfusion of blood products is a vital component of many advanced pre-hospital systems. Portable fluid warmers may be utilised to help prevent hypothermia, but the limits defined by manufacturers often do not reflect their clinical use. The primary aim of this randomised in-vitro study was to assess the warming performance of four portable blood warming devices (Thermal Angel, Hypotherm X LG, °M Warmer, Buddy Lite) against control at different clinically-relevant flow rates. The secondary aim was to assess haemolysis rates between devices at different flow rates. We assessed each of the four devices and the control, at flow rates of 50 ml.min-1 , 100 ml.min-1 and 200 ml.min-1 , using a controlled perfusion circuit with multisite temperature monitoring. Free haemoglobin concentration, a marker of haemolysis, was measured at multiple points during each initial study run with spectrophotometry. At all flow rates, the four devices provided superior warming performance compared with the control (p < 0.001). Only the °M Warmer provided a substantial change in temperature at all flow rates (mean (95%CI) temperature change of 21.1 (19.8-22.4) °C, 20.4 (19.1-21.8) °C and 19.4 (17.7-21.1) °C at 50 ml.min-1 , 100 ml.min-1 and 200 ml.min-1 , respectively). There was no association between warming and haemolysis with any device (p = 0.949) or flow rate (p = 0.169). Practical issues, which may be relevant to clinical use, also emerged during testing. Our results suggest that there were significant differences in the performance of portable blood warming devices used at flow rates encountered in clinical practice.


Assuntos
Transfusão de Sangue , Serviços Médicos de Emergência , Calefação/instrumentação , Hipotermia/prevenção & controle , Hemoglobinas/análise , Hemólise , Humanos
18.
Pan Afr Med J ; 32: 43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143348

RESUMO

Histoplasmosis is an endemic mycosis with global distribution, primarily reported in immunocompromised individuals. A 29-year old immunocompetent male presented with fever, hepatosplenomegaly and pancytopenia. His peripheral blood showed features suggestive of intravascular hemolysis and echocardiography showed features suggestive of pulmonary arterial hypertension. Bone marrow showed yeast with morphology suggestive of Histoplasma capsulatum. Further investigations revealed hyperferritinemia, hypofibrinogenemia and increased triglycerides. With a diagnosis of progressive disseminated histoplasmosis with secondary Haemophagocytic lymphohistiocytosis, he was successfully treated with amphotericin B followed by itraconazole. We report this case to highlight the atypical and rare manifestations of histoplasmosis.


Assuntos
Antifúngicos/administração & dosagem , Insuficiência Cardíaca/etiologia , Histoplasmose/diagnóstico , Linfo-Histiocitose Hemofagocítica/etiologia , Adulto , Anfotericina B/administração & dosagem , Febre/etiologia , Hemólise , Hepatomegalia/etiologia , Histoplasmose/complicações , Histoplasmose/tratamento farmacológico , Humanos , Imunocompetência , Itraconazol/administração & dosagem , Masculino , Pancitopenia/etiologia , Esplenomegalia/etiologia
19.
J Photochem Photobiol B ; 196: 111496, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129507

RESUMO

Surgical resection is one of the most common radical treatments for cancers. However, tumors may be compressed or the local intravascular pressure may be increased during surgical manipulation, causing the shedding and entry of tumor cells into the blood circulation and hence distant recurrence and metastasis of tumors. We have preliminarily established a method of riboflavin photosensitization treatment (RPT) for inactivation of circulating tumor cells. This technology promises to solve the problems of shedding and entry of solid tumor cells into blood circulation before surgical manipulation, and almost unavoidable hematogenous dissemination of tumor cells during surgical resection. In the present study, apoptosis detection and tumorigenicity experiment in immunodeficient mice were conducted to evaluate the effect of RPT for inactivation of circulating tumor cells respectively. Next, functional evaluation was carried out for the immune cells through detecting apoptosis rate and cytokine secretion of lymphocyte. Finally, thromboelastography (TEG) and free hemoglobin were detected to assess peripheral blood coagulation and red blood cell damage. The results showed that RPT (50 µmol/L riboflavin, 10.8 J/cm2 UV) could effectively make tumor cell lose the ability of proliferation in the peripheral blood. In the meantime, the damage caused to peripheral blood coagulation, immune cell function and red blood cells was generally acceptable. The results of the study showed that RPT had huge potential in addressing the problems of shedding and entry of solid tumor cells into blood circulation before surgical manipulation, and almost unavoidable hematogenous dissemination of tumor cells during surgical resection. This therapy is expected to be an auxiliary and supportive method to reduce the risk of hematogenous metastasis and recurrence of cancers, and to increase the surgical success rate of malignant solid tumors.


Assuntos
Células Neoplásicas Circulantes/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Coagulação Sanguínea/efeitos dos fármacos , Citocinas/metabolismo , Feminino , Células HCT116 , Hemólise/efeitos dos fármacos , Humanos , Luz , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias/tratamento farmacológico , Células Neoplásicas Circulantes/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico
20.
Clin Biochem ; 70: 46-48, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31059687

RESUMO

OBJECTIVE: Develop sample acceptability rules by determining the relationship between free hemoglobin level (hemolysis) and potassium or ionized calcium in blood gas samples collected intraoperatively. DESIGN AND METHODS: Hemolysis was assessed visually or by H index for lithium heparin blood gas samples collected intraoperatively. During periods one and three this was done using two different rules for visual assessment of centrifuged lithium heparin plasma. During period two H index was measured for all visually hemolyzed samples on a Roche Cobas c501 analyzer to determine acceptability. Potassium and ionized calcium were measured in 75 lithium heparin whole blood samples on a Radiometer ABL90 to correlate H index and potassium or ionized calcium. RESULTS: During period one 35 of 5808 (0.6%) blood gas samples had visual hemolysis levels exceeding tolerance for reporting of potassium. By switching to measured H index using a laboratory-established threshold, during period 2 we estimate that 171 of 5396 (3.2%) blood gas samples exceeded the H index threshold for reporting of potassium. In 75 intraoperative blood gas samples with H index and whole blood potassium and ionized calcium measured; we observed no relationship between H index and potassium or ionized calcium. During period 3 we switched to visual assessment of hemolysis with a greater tolerance for hemolysis; with only 3 of 5345 (0.06%) samples exceeding the new visual hemolysis threshold. CONCLUSION: For blood gas samples collected intraoperatively, there is no relationship between hemolysis and measured potassium or ionized calcium. The results suggest that only grossly hemolyzed intraoperative blood gas samples should be rejected for measurement of whole blood potassium and ionized calcium.


Assuntos
Gasometria/métodos , Cálcio/sangue , Hemoglobinas/análise , Hemólise , Heparina/sangue , Lítio/sangue , Potássio/sangue , Testes Hematológicos , Período Intraoperatório , Manejo de Espécimes
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