RESUMO
BACKGROUND: Ten years after their availability, thrombopoietin receptor agonists (TPO-RA) have heralded a paradigm shift in the treatment of immune thrombocytopenia (ITP). This study was aimed to analyze the implementation of current recommendations in the standard practice of adult ITP patients, and how age may influence those changes. METHODS: We included 121 adult patients (> 65 years, n = 54; younger individuals, n = 67) who initiated treatment with TPO-RA between January 2012 and December 2014. RESULTS: Patients older than 65 years treated with TPO-RA presented at diagnosis with significantly higher platelet counts, less bleeding, and a more prothrombotic profile than younger ones. The high efficacy rates of TPO-RA, preferentially used during the last decade in non-chronic phases, precluded from further therapies in the majority of ITP patients. Their administration was associated with a sharp decline in the last decade in the use of splenectomy and intravenous immunoglobulin, especially in younger ITP individuals. CONCLUSION: These results confirm (1) that there is a preferential use of TPO-RAs in elderly ITP patients with fewer bleeding complications but more unfavorable prothrombotic conditions than in younger individuals, and (2) that early use of these agents has been established as an effective therapeutic alternative to other second line therapies.
Assuntos
Púrpura Trombocitopênica Idiopática/terapia , Receptores de Trombopoetina/agonistas , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Púrpura Trombocitopênica Idiopática/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Large studies in von Willebrand disease patients, including Spanish and Portuguese registries, led to the identification of >250 different mutations. It is a challenge to determine the pathogenic effect of potential splice site mutations on VWF mRNA. This study aimed to elucidate the true effects of 18 mutations on VWF mRNA processing, investigate the contribution of next-generation sequencing to in vivo mRNA study in von Willebrand disease, and compare the findings with in silico prediction. RNA extracted from patient platelets and leukocytes was amplified by RT-PCR and sequenced using Sanger and next generation sequencing techniques. Eight mutations affected VWF splicing: c.1533+1G>A, c.5664+2T>C and c.546G>A (p.=) prompted exon skipping; c.3223-7_3236dup and c.7082-2A>G resulted in activation of cryptic sites; c.3379+1G>A and c.7437G>A) demonstrated both molecular pathogenic mechanisms simultaneously; and the p.Cys370Tyr missense mutation generated two aberrant transcripts. Of note, the complete effect of three mutations was provided by next generation sequencing alone because of low expression of the aberrant transcripts. In the remaining 10 mutations, no effect was elucidated in the experiments. However, the differential findings obtained in platelets and leukocytes provided substantial evidence that four of these would have an effect on VWF levels. In this first report using next generation sequencing technology to unravel the effects of VWF mutations on splicing, the technique yielded valuable information. Our data bring to light the importance of studying the effect of synonymous and missense mutations on VWF splicing to improve the current knowledge of the molecular mechanisms behind von Willebrand disease. clinicaltrials.gov identifier:02869074.
Assuntos
Inativação Gênica , Íntrons , Mutação de Sentido Incorreto , Splicing de RNA , Fator de von Willebrand/genética , Alelos , Sequência de Bases , Plaquetas/metabolismo , Biologia Computacional , Éxons , Feminino , Frequência do Gene , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucócitos/metabolismo , Masculino , Sítios de Splice de RNA , RNA Mensageiro/genética , Doenças de von Willebrand/genéticaRESUMO
AIM: The use of musculoskeletal ultrasound (MSK-US) following protocols for haemophilic arthropathy and the Haemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) score can help standardize monitoring in haemophilia. This study evaluated the joint status (elbows, knees and ankles) of patients with haemophilia B (HB) in Spain using MSK-US and the HEAD-US score. METHODS: Haemophilia B patients ≥14 years old were included in this observational, multicentre, cross-sectional study, regardless of their clinical condition, HB severity and treatment received. Two blinded observers were involved in image acquisition and scoring in each centre. RESULTS: Eighty-two patients from 12 centres were enrolled: 27% mild HB, 23% moderate, 50% severe HB. Mean age was 38.9 ± 16.4 years, 60% were treated on demand (OD) and 40% were on prophylaxis. HEAD-US was zero in all joints in 28.6% OD patients and 36.4% on prophylaxis. Mean scores significantly worsened with HB severity, except for the left knee. Patients on primary and secondary prophylaxis had significantly better joint health vs OD patients in all joints, except the right ankle. Among OD patients, those with severe disease presented significantly worse scores in all HEAD-US items related to permanent damage. CONCLUSION: Joint status of HB patients in Spain is influenced by severity and treatment modality, related to the development of arthropathy, which appears prevalent in OD patients with severe HB. Routine assessment with an imaging tool such as ultrasound and HEAD-US system may help to improve joint health by personalizing and adjusting treatment in this population.
Assuntos
Hemofilia B/patologia , Artropatias/diagnóstico , Articulações/diagnóstico por imagem , Sinovite/diagnóstico , Adolescente , Adulto , Estudos Transversais , Humanos , Artropatias/patologia , Modelos Logísticos , Pessoa de Meia-Idade , Razão de Chances , Índice de Gravidade de Doença , Espanha , Sinovite/patologia , Ultrassonografia , Adulto JovemRESUMO
OBJECTIVE: Here, we provide evidence for the role of FLNA (filamin A) in the modulation of store-operated calcium entry (SOCE). APPROACH AND RESULTS: SOCE is a major mechanism for calcium influx controlled by the intracellular Ca2+ stores. On store depletion, the endoplasmic reticulum calcium sensor STIM1 (stromal interaction molecule 1) redistributes into puncta at endoplasmic reticulum/plasma membrane junctions, a process supported by the cytoskeleton, where it interacts with the calcium channels; however, the mechanism for fine-tuning SOCE is not completely understood. Our results demonstrate that STIM1 interacts with FLNA on calcium store depletion in human platelets. The interaction is dependent on the phosphorylation of FLNA at Ser2152 by the cAMP-dependent protein kinase. Impairment of FLNA phosphorylation and knockdown of FLNA expression using siRNA increased SOCE in platelets. Similarly, SOCE was significantly greater in FLNA-deficient melanoma M2 cells than in the FLNA-expressing M2 subclone A7. Expression of FLNA in M2 cells attenuated SOCE, an effect prevented when the cells were transfected with the nonphosphorylatable FLNA S2152A mutant. Transfection of M2 cells with the STIM1(K684,685E) mutant reduced the STIM1-FLNA interaction. In platelets, attenuation of FLNA expression using siRNA resulted in enhanced association of STIM1 with the cytoskeleton, greater STIM1-Orai1 interaction, and SOCE. Introduction of an anti-FLNA (2597-2647) antibody attenuated the STIM1-FLNA interaction and enhanced thrombin-induced platelet aggregation. CONCLUSIONS: Our results indicate that FLNA modulates SOCE and then the correct platelet function, by fine-tuning the distribution of STIM1 in the cytoskeleton and the interaction with Orai1 channels.
Assuntos
Plaquetas/metabolismo , Sinalização do Cálcio , Cálcio/metabolismo , Filaminas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Linhagem Celular Tumoral , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Citoesqueleto/metabolismo , Filaminas/genética , Humanos , Ativação do Canal Iônico , Melanoma/genética , Melanoma/metabolismo , Proteínas de Neoplasias/genética , Proteína ORAI1/genética , Fosforilação , Agregação Plaquetária , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Serina , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Molécula 1 de Interação Estromal/genéticaRESUMO
Inherited platelet disorders are a heterogeneous group of rare diseases, caused by inherited defects in platelet production and/or function. Their genetic diagnosis would benefit clinical care, prognosis and preventative treatments. Until recently, this diagnosis has usually been performed via Sanger sequencing of a limited number of candidate genes. High-throughput sequencing is revolutionizing the genetic diagnosis of diseases, including bleeding disorders. We have designed a novel high-throughput sequencing platform to investigate the unknown molecular pathology in a cohort of 82 patients with inherited platelet disorders. Thirty-four (41.5%) patients presented with a phenotype strongly indicative of a particular type of platelet disorder. The other patients had clinical bleeding indicative of platelet dysfunction, but with no identifiable features. The high-throughput sequencing test enabled a molecular diagnosis in 70% of these patients. This sensitivity increased to 90% among patients suspected of having a defined platelet disorder. We found 57 different candidate variants in 28 genes, of which 70% had not previously been described. Following consensus guidelines, we qualified 68.4% and 26.3% of the candidate variants as being pathogenic and likely pathogenic, respectively. In addition to establishing definitive diagnoses of well-known inherited platelet disorders, high-throughput sequencing also identified rarer disorders such as sitosterolemia, filamin and actinin deficiencies, and G protein-coupled receptor defects. This included disease-causing variants in DIAPH1 (n=2) and RASGRP2 (n=3). Our study reinforces the feasibility of introducing high-throughput sequencing technology into the mainstream laboratory for the genetic diagnostic practice in inherited platelet disorders.
Assuntos
Transtornos Plaquetários/diagnóstico , Transtornos Plaquetários/genética , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/genética , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Plaquetas/metabolismo , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Fenótipo , Reprodutibilidade dos Testes , Análise de Sequência de DNA , Adulto JovemRESUMO
Excessive bleeding at surgery is a feared complication in patients with inherited platelet disorders. However, very few studies have evaluated the frequency of surgical bleeding in these hemorrhagic disorders. We performed a worldwide, multicentric, retrospective study to assess the bleeding complications of surgery, the preventive and therapeutic approaches adopted, and their efficacy in patients with inherited platelet disorders: the Surgery in Platelet disorders And Therapeutic Approach (SPATA) study. We rated the outcome of 829 surgical procedures carried out in 423 patients with well-defined forms of inherited platelet disorders: 238 inherited platelet function disorders and 185 inherited platelet number disorders. Frequency of surgical bleeding was high in patients with inherited platelet disorders (19.7%), with a significantly higher bleeding incidence in inherited platelet function disorders (24.8%) than in inherited platelet number disorders (13.4%). The frequency of bleeding varied according to the type of inherited platelet disorder, with biallelic Bernard Soulier syndrome having the highest occurrence (44.4%). Frequency of bleeding was predicted by a pre-operative World Health Organization bleeding score of 2 or higher. Some types of surgery were associated with a higher bleeding incidence, like cardiovascular and urological surgery. The use of pre-operative pro-hemostatic treatments was associated with a lower bleeding frequency in patients with inherited platelet function disorders but not in inherited platelet number disorders. Desmopressin, alone or with antifibrinolytic agents, was the preventive treatment associated with the lowest bleedings. Platelet transfusions were used more frequently in patients at higher bleeding risk. Surgical bleeding risk in inherited platelet disorders is substantial, especially in inherited platelet function disorders, and bleeding history, type of disorder, type of surgery and female sex are associated with higher bleeding frequency. Prophylactic pre-operative pro-hemostatic treatments appear to be required and are associated with a lower bleeding incidence.
Assuntos
Transtornos Plaquetários/congênito , Transtornos Plaquetários/complicações , Hemorragia/etiologia , Hemorragia/prevenção & controle , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos Plaquetários/diagnóstico , Criança , Pré-Escolar , Feminino , Hemorragia/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados da Assistência ao Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Pré-Medicação/métodos , Medição de Risco , Fatores de Risco , Procedimentos Cirúrgicos Operatórios/métodos , Resultado do Tratamento , Adulto JovemRESUMO
Molecular diagnosis of patients with von Willebrand disease is pending in most populations due to the complexity and high cost of conventional molecular analyses. The need for molecular and clinical characterization of von Willebrand disease in Spain prompted the creation of a multicenter project (PCM-EVW-ES) that resulted in the largest prospective cohort study of patients with all types of von Willebrand disease. Molecular analysis of relevant regions of the VWF, including intronic and promoter regions, was achieved in the 556 individuals recruited via the development of a simple, innovative, relatively low-cost protocol based on microfluidic technology and next-generation sequencing. A total of 704 variants (237 different) were identified along VWF, 155 of which had not been previously recorded in the international mutation database. The potential pathogenic effect of these variants was assessed by in silico analysis. Furthermore, four short tandem repeats were analyzed in order to evaluate the ancestral origin of recurrent mutations. The outcome of genetic analysis allowed for the reclassification of 110 patients, identification of 37 asymptomatic carriers (important for genetic counseling) and re-inclusion of 43 patients previously excluded by phenotyping results. In total, 480 patients were definitively diagnosed. Candidate mutations were identified in all patients except 13 type 1 von Willebrand disease, yielding a high genotype-phenotype correlation. Our data reinforce the capital importance and usefulness of genetics in von Willebrand disease diagnostics. The progressive implementation of molecular study as the first-line test for routine diagnosis of this condition will lead to increasingly more personalized and effective care for this patient population.
Assuntos
Doenças de von Willebrand/genética , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Espanha/epidemiologia , Doenças de von Willebrand/diagnóstico , Fator de von Willebrand/genéticaAssuntos
Ciclo-Oxigenase 1/genética , Transtornos Hemorrágicos/genética , Mutação com Perda de Função , Mutação de Sentido Incorreto , Ativação Plaquetária/genética , Processamento de Proteína Pós-Traducional/genética , Adolescente , Povo Asiático/genética , Ciclo-Oxigenase 1/deficiência , Ciclo-Oxigenase 1/metabolismo , Feminino , Genes Dominantes , Glicosilação , Células HEK293 , Transtornos Hemorrágicos/sangue , Heterozigoto , Humanos , Fenótipo , Ativação Plaquetária/fisiologiaRESUMO
Fruit quality is essential for nutrition and human health and needs urgent attention in current agricultural practices. Organic farming is not as productive as conventional agriculture, but it can provide higher quality in some fruit crops, thanks to the absence of synthetic fertilizers and pesticides, enhanced pollination, and the reduction of protection treatments, hence boosting antioxidant compound production. Although organic farming does not always provide healthier food than conventional farming, some lessons from organic farming can be extrapolated to new sustainable production models. Exploiting natural resources and an adequate knowledge transfer will undoubtedly help improve the quality of climacteric and nonclimacteric fruits in new agricultural systems.
Assuntos
Agricultura , Produtos Agrícolas , Frutas , Agricultura Orgânica , Agricultura Orgânica/métodos , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Agricultura/métodos , Fertilizantes/análiseRESUMO
Climate change is currently considered as one of the main concerns of the agriculture sector, as it limits crop production and quality. Furthermore, the current context of global crisis with international political instability and war conflicts over the world is pushing the agriculture sector even more to urgently boost productivity and yield and doing so in a sustainable way in the current frame of climate change. Biostimulants can be an effective tool in alleviating the negative effects of environmental stresses to which plants are exposed, such as drought, salinity, heavy metals and extreme temperatures etc. Biostimulants act through multiple mechanisms, modifying gene expression, metabolism and phytohormone production, promoting the accumulation of compatible solutes and antioxidants and mitigating oxidative stress. However, it is important to keep in mind that the use and effect of biostimulants has limitations and must be accompanied by other techniques to ensure crop yield and quality in the current frame of climate change, such as proper crop management and the use of other sustainable resources. Here, we will not only highlight the potential use of biostimulants to face future agricultural challenges, but also take a critical look at their limitations, underlining the importance of a broad vision of sustainable agriculture in the context of climate change.
Assuntos
Agricultura , Mudança Climática , Produtos Agrícolas , Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Reguladores de Crescimento de Plantas/metabolismoRESUMO
Background: In hemophilia and von Willebrand disease, the degree of alteration of laboratory assays correlates with bleeding manifestations. Few studies have assessed the predictive value for bleeding of laboratory assays in patients with inherited platelet function disorders (IPFDs). Objectives: To assess whether there is an association between platelet function assay results and bleeding history, as evaluated by the International Society on Thrombosis and Haemostasis (ISTH) bleeding assessment tool (BAT). Methods: Centers participating in the international ISTH-BAT validation study were asked to provide results of the diagnostic assays employed for the patients they enrolled, and the association with the individual patients' bleeding score (BS) was assessed. Results: Sixty-eight patients with 14 different IPFDs were included. Maximal amplitude of platelet aggregation was significantly lower in patients with a pathologic BS and correlated inversely with the BS, a finding largely driven by the subgroup of patients with Glanzmann thrombasthenia and CalDAG-GEFI deficiency; after their exclusion, TRAP-induced aggregation remained significantly lower in patients with a pathologic BS. Bleeding time was significantly more prolonged in patients with a high BS than in those with a normal BS (27.1 ± 6.2 minutes vs 15.1 ± 10.6 minutes; P < .01). Reduced α-granule content was significantly more common among patients with a pathologic BS than among those with a normal BS (80% vs 20%; P < .05). Receiver operating characteristic curve analysis revealed a significant discriminative ability of all the aforementioned tests for pathologic BS (P < .001), also after exclusion of patients with Glanzmann thrombasthenia and CalDAG-GEFI deficiency. Conclusion: This study shows that altered platelet laboratory assay results are associated with an abnormal ISTH-BAT BS in IPFD.
RESUMO
The use of the mammal target of rapamycin (mTOR) inhibitors has been consolidated as the therapy of election for preventing graft rejection in kidney transplant patients, despite their immunosuppressive activity is less strong than anti-calcineurin agents like tacrolimus and cyclosporine A. Furthermore, as mTOR is widely expressed, rapamycin (a macrolide antibiotic produced by Streptomyces hygroscopicus) is recommended in patients presenting neoplasia due to its antiproliferative actions. Hence, we have investigated whether rapamycin presents side effects in the physiology of other cell types different from leucocytes, such as platelets. Blood samples were drawn from healthy volunteers and kidney transplant patients long-term medicated with rapamycin: sirolimus and everolimus. Platelets were either loaded with fura-2 or directly stimulated, and immunoassayed or fixed with Laemmli's buffer to perform the subsequent analysis of platelet physiology. Our results indicate that rapamycin evokes a biphasic time-dependent alteration in calcium homeostasis and function in platelets from kidney transplant patients under rapamycin regime, as demonstrated by the reduction in granule secretion observed and subsequent impairment of platelet aggregation in these patients compared with healthy volunteers. Platelet count was also reduced in these patients, thus 41% of patients presented thrombocytopenia. All together our results show that long-term administration of rapamycin to kidney transplant patients evokes alteration in platelet function.
Assuntos
Plaquetas/patologia , Cálcio/metabolismo , Homeostase/efeitos dos fármacos , Transplante de Rim , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adulto , Idoso , Plaquetas/efeitos dos fármacos , Demografia , Ativação Enzimática/efeitos dos fármacos , Everolimo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Fatores de TempoRESUMO
Homer is a family of cytoplasmic adaptor proteins that play different roles in cell function, including the regulation of G-protein-coupled receptors. These proteins contain an Ena (Enabled)/VASP (vasodilator-stimulated phosphoprotein) homology 1 domain that binds to the PPXXF sequence motif, which is present in different Ca²âº-handling proteins such as IP3 (inositol 1,4,5-trisphosphate) receptors and TRPC (transient receptor potential canonical) channels. In the present study we show evidence for a role of Homer proteins in the STIM1 (stromal interaction molecule 1)-Orai1 association, as well as in the TRPC1-IP3RII (type II IP3 receptor) interaction, which might be of relevance in platelet function. Treatment of human platelets with thapsigargin or thrombin results in a Ca²âº-independent association of Homer1 with TRPC1 and IP3RII. In addition, thapsigargin and thrombin enhanced the association of Homer1 with STIM1 and Orai1 in a Ca²âº-dependent manner. Interference with Homer function by introduction of the synthetic PPKKFR peptide into cells, which emulates the proline-rich sequences of the PPXXF motif, reduced STIM1-Orai1 and TRPC1- IP3RII associations, as compared with the introduction of the inactive PPKKRR peptide. The PPKKFR peptide attenuates thrombin-evoked Ca²âº entry and the maintenance of thapsigargin-induced store-operated Ca²âº entry. Finally, the PPKKFR peptide attenuated thrombin-induced platelet aggregation. The findings of the present study support an important role for Homer proteins in thrombin-stimulated platelet function, which is likely to be mediated by the support of agonist-induced Ca²âº entry.
Assuntos
Plaquetas/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Proteínas de Transporte/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Canais de Cátion TRPC/metabolismo , Plaquetas/efeitos dos fármacos , Western Blotting , Sinalização do Cálcio/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas de Arcabouço Homer , Humanos , Imunoprecipitação , Inositol 1,4,5-Trifosfato/metabolismo , Proteína ORAI1 , Fragmentos de Peptídeos/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Ligação Proteica , Molécula 1 de Interação Estromal , Tapsigargina/farmacologiaRESUMO
Various approaches can be used to improve chemical food composition avoiding the low acceptance risks that imply the use of transgenic crops. Here, we evaluated the antioxidant vitamin composition of dry and germinating seeds and sprouts of chia and examined the potential of exploiting natural variation of developmental stages to improve vitamin contents in chia-derived foodstuffs. Results showed that dry seeds contained the highest contents of vitamin E, with values 8-fold higher compared to sprouts. Vitamin C contents strongly increased just after seed imbibition, so that germinating seeds contained 5- and 17.5-fold higher values than dry seeds and sprouts, respectively. Sprouts displayed the highest contents of carotenoids (including ß-carotene [pro-vitamin A]). We conclude that mixing dry seeds, germinating seeds and sprouts (in a proportion of 1.5:2:1 w/w/w) may be a cost-effective way to obtain an optimal composition of antioxidant vitamins in foodstuffs such as salads.
Assuntos
Antioxidantes , Salvia , Antioxidantes/química , Salvia/química , Vitaminas/análise , Análise Custo-Benefício , Sementes/químicaRESUMO
BACKGROUND: Light transmission aggregation (LTA) is used widely by the clinical and research communities. Although it is a gold standard, there is a lack of interlaboratory harmonization. OBJECTIVES: The primary objective was to assess whether sources of activators (mainly adenosine diphosphate [ADP], collagen, arachidonic acid, epinephrine, and thrombin receptor activating peptide6) and ristocetin contribute to poor LTA reproducibility. The secondary objective was to evaluate interindividual variability of results to appreciate the distribution of normal values and consequently better interpret pathologic results. METHODS: An international multicenter study involving 28 laboratories in which we compared LTA results obtained with center-specific activators and a comparator that we supplied. RESULTS: We report variability in the potency (P) of activators in comparison with the comparator. Thrombin receptor activating peptide 6 (P, 1.32-2.68), arachidonic acid (P, 0.87-1.43), and epinephrine (P, 0.97-1.34) showed the greatest variability. ADP (P, 1.04-1.20) and ristocetin (P, 0.98-1.07) were the most consistent. The data highlighted clear interindividual variability, notably for ADP and epinephrine. Four profiles of responses were observed with ADP from high-responders, intermediate-responders, and low-responders. A fifth profile corresponding to nonresponders (5% of the individuals) was observed with epinephrine. CONCLUSION: Based on these data, the establishment and adoption of simple standardization principles should mitigate variability due to activator sources. The observation of huge interindividual variability for certain concentrations of activators should lead to a cautious interpretation before reporting a result as abnormal. Confidence can be taken from the fact that difference between sources is not exacerbated in patients treated with antiplatelet agents.
Assuntos
Agregação Plaquetária , Ristocetina , Humanos , Ácido Araquidônico/farmacologia , Reprodutibilidade dos Testes , Difosfato de Adenosina/farmacologia , Testes de Função Plaquetária/métodos , Inibidores da Agregação Plaquetária/farmacologia , Epinefrina/farmacologia , Comunicação , PlaquetasRESUMO
Chia (Salvia hispanica) is a native plant species from South America that is very appreciated for its oleaginous seeds in the agri-food field. Chia seeds are natural sources of many bioactive compounds which provide benefits to human health. Nevertheless, chia sprouts have better nutritional properties than seeds, such as antioxidants, essential amino acids, and phenolic compounds. Among all these beneficial compounds, ß-carotene has not been studied in chia sprouts. ß-carotene is a precursor of vitamin A, which contributes to maintaining our health status. In this study, to improve ß-carotene content in chia sprouts, some plant growth regulators (abscisic acid, methyl jasmonate and methyl salicylate) were applied exogenously to germinating chia seeds. Gibberellins A4/A7 and cytokinin 6-benzyladenine (Promalin®) were also applied, combined with the other regulators, to antagonize a possible inhibition in the germination. Seeds were grown in darkness for 4 days, then seeds were exposed to a short light stimulus (30') and finally to a continued light stimulus (48h). ß-carotene, xanthophylls, chlorophylls, de-epoxidation status of xanthophyll cycle (DPS), germination rate, and sprouts fresh weight were analysed. The results show that sprouts treated with methyl salicylate in-creased 2,35 fold their ß-carotene content when they were exposed to light for 30'+48h. Sprouts fresh weight and germination were not affected by methyl salicylate. Although more research is needed before industrial application, it is concluded that methyl salicylate can be used to improve ß-carotene contents in chia sprouts.
Assuntos
Salvia , Biofortificação , Reguladores de Crescimento de Plantas , Salvia hispanica , beta CarotenoRESUMO
The clinical diagnosis of von Willebrand disease (VWD), particularly type 1, can be complex because several genetic and environmental factors affect von Willebrand factor (VWF) plasma levels. An estimated 60% of the phenotypic variation is attributable to hereditary factors, with the ABO blood group locus being the most influential. However, recent studies provide strong evidence that nonsynonymous single nucleotide variants (SNVs) contribute to VWF and factor VIII phenotypic variability in healthy individuals. This study aims to investigate the role of common VWF SNVs on VWD phenotype by analyzing data from 219 unrelated patients included in the "Molecular and Clinical Profile of von Willebrand Disease in Spain project." To that end, generalized linear mixed-effects regression models were fitted, and additive and epistatic analyses, and haplotype studies were performed, considering five VWD-related measures (bleeding score, VWF:Ag, VWF:RCo, factor VIII:C, and VWF:CB). According to these analyses, homozygotes: for p.Thr789Ala(C) would be expected to show 39% higher VWF:Ag levels; p.Thr1381Ala(C), 27% lower VWF:Ag levels; and p.Gln852Arg(C), 52% lower VWF:RCo levels. Homozygotes for both p.Thr789Ala(C) and p.Gln852Arg(T) were predicted to show 185% higher VWF:CB activity, and carriers of two copies of the p.Thr1381Ala(T)/p.Gln852Arg(T) haplotype would present a 100% increase in VWF:RCo activity. These results indicate a substantial effect of common VWF variation on VWD phenotype. Although additional studies are needed to determine the true magnitude of the effects of SNVs on VWF, these findings provide new evidence regarding the contribution of common variants to VWD, which should be taken into account to enhance the accuracy of the diagnosis and classification of this condition. ClinicalTrials.gov identifier: NCT02869074.
Assuntos
Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Doenças de von Willebrand/sangue , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Adulto , Simulação por Computador , Fator VIII/genética , Fator VIII/metabolismo , Feminino , Haplótipos , Hemorragia , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Sistema de Registros , Análise de Regressão , Espanha , Adulto Jovem , Fator de von Willebrand/químicaRESUMO
Background: Hermansky-Pudlak syndrome (HPS) is a rare inherited platelet disorder characterized by bleeding diathesis, oculocutaneous albinism (OCA) and a myriad of often-serious clinical complications. Methods: We established the clinical and laboratory phenotype and genotype of six unrelated pedigrees comprising ten patients with clinical suspicion of HPS; including platelet aggregation, flow cytometry, platelet dense granule content, electron microscopy and high-throughput sequencing (HTS). Results: The clinical presentation showed significant heterogeneity and no clear phenotype-genotype correlations. HTS revealed two known and three novel disease-causing variants. The Spanish patients carried a homozygous p.Pro685Leufs17* deletion (n = 2) in HPS4, or the novel p.Arg822* homozygous variant (n = 1) in HPS3. In the case of two Turkish sisters, a novel missense homozygous HPS4 variant (p.Leu91Pro) was found. In two Portuguese families, genetic studies confirmed a previously reported nonsense variant (p.Gln103*) in DTNBP1 in three patients and a novel duplication (p.Leu22Argfs*33) in HPS6 in two unrelated patients. Conclusions: Our findings expand the mutational spectrum of HPS, which may help in investigating phenotype-genotype relationships and assist genetic counselling for affected individuals. This approach is a proof of principle that HTS can be considered and used in the first-line diagnosis of patients with biological and clinical manifestations suggestive of HPS. Key messages We established the relationships between the clinical and laboratory phenotype and genotype of six unrelated pedigrees comprising ten patients with clinical suspicion of HPS. Molecular analysis is useful in confirming the diagnosis and may offer some prognostic information that will aid in optimizing monitoring and surveillance for early detection of end-organ damage. This approach is a proof of principle that HTS can be considered and used in the first-line diagnosis of patients with biological and clinical manifestations suggestive of HPS.
Assuntos
Síndrome de Hermanski-Pudlak/genética , Sequenciamento de Nucleotídeos em Larga Escala , Adolescente , Adulto , Criança , Feminino , Variação Genética , Síndrome de Hermanski-Pudlak/diagnóstico , Síndrome de Hermanski-Pudlak/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , FenótipoRESUMO
Very few data exist on when a particular thrombopoietin-receptor agonist (TPO-RA) is favored in clinical practice for the treatment of patients with immune thrombocytopenia (ITP), about novel risk factors for vascular events (VE) with these drugs, nor about predictive factors for therapy free responses (TFR). We conducted an observational, retrospective, long-term follow-up multicenter study from November 2016 to January 2018 of 121 adult ITP patients initiating TPO-RA between January 2012 to December 2014. Data reflected that a platelet count ≤25 × 109/l at the time when the TPO-RA was initiated was associated with a 2.8 higher probability of receiving romiplostim vs. eltrombopag (P = 0.010). VE on TPO-RA was related to previous neoplasia in patients over 65 years (50% vs. 2.2%, P < 0.001), and to previous splenectomy in younger patients (100% vs. 33%, P = 0.001). Receiving romiplostim as first TPO-RA with no subsequent TPO-RA switching was associated with a 50% likelihood of TFR after 2.9 years of therapy (3.3 years in chronic ITP patients). These real-world data help deciphering some areas of uncertainty, and offer insight into some of the most relevant challenges of ITP which may help clinicians make appropriate treatment decisions in the management of adult ITP patients with TPO-RA.