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1.
Orphanet J Rare Dis ; 18(1): 366, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007560

RESUMO

With the first gene therapies for haemophilia approved by the European Commission, the US Food and Drug Administration, and the Medicines and Healthcare products Regulatory Agency, it is important to consider the remaining unmet needs and challenges that may arise throughout patients' treatment journeys. We discuss existing unmet needs and important considerations prior to, during, and following haemophilia gene therapy treatment in the UK, and propose potential next steps. Key areas for attention are education, psychological support, and guidance on implementation. Strategies are urgently required to fulfil these needs. An immediate priority for information providers should be comprehensive education for people with haemophilia (PWH) and healthcare professionals (HCPs). Greater access to resources and training in psychological services will be required throughout the treatment pathway. More specific guidance is required to define the implementation model, criteria for accreditation, and responsibilities of care centres. Furthermore, PWH may revisit discussions with HCPs multiple times pre-infusion, thus the patient journey is unlikely to be linear. Consideration of these challenges, and of potential strategies to address them, will be integral to optimising the future success of this promising therapy.


Assuntos
Hemofilia A , Humanos , Hemofilia A/terapia , Atenção à Saúde , Pessoal de Saúde , Reino Unido
2.
J Thromb Haemost ; 21(12): 3450-3462, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37678546

RESUMO

BACKGROUND: Severe hemophilia A (HA) negatively impacts health-related quality of life (HRQOL). OBJECTIVES: We aimed to analyze HRQOL in adult men with severe HA without inhibitors after valoctocogene roxaparvovec gene transfer in the phase 3 trial GENEr8-1. METHODS: Participant-reported outcomes were the hemophilia-specific quality of life questionnaire for adults (Haemo-QOL-A), the EQ-5D-5L instrument, the Hemophilia Activities List (HAL), and the Work Productivity and Activity Impairment Questionnaire: Hemophilia Specific (WPAI+CIQ:HS). Participants completed the questionnaires at baseline and through 104 weeks postinfusion with 6 × 1013 vg/kg of valoctocogene roxaparvovec. Scores were analyzed per participant characteristics and outcomes. RESULTS: For 132 HIV-negative participants, mean change from baseline in Haemo-QOL-A Total Score met the anchor-based clinically important difference (CID: 5.5) by week 12; the mean (SD) increase was 7.0 (12.6) at week 104. At week 104, improvement in Consequences of Bleeding, Treatment Concern, Worry, and Role Functioning domain scores exceeded the CID (6). EQ-5D-5L Utility Index scores improved above the CID at week 52, but not at week 104. EQ-5D-5L visual analog scale and HAL scores increased from baseline to week 104. Participants reported less activity and work impairment at week 104 than baseline. Participants with problem joints had lower mean baseline Haemo-QOL-A Total and domain scores than those without them, but improved over 104 weeks, except for 11 participants with ≥3 problem joints. Participants with 0 bleeds during the baseline prophylaxis period reported Haemo-QOL-A score improvements above the CID, including in the Consequences of Bleeding domain. CONCLUSION: Valoctocogene roxaparvovec provided clinically meaningful HRQOL improvement for men with severe HA.


Assuntos
Hemofilia A , Adulto , Masculino , Humanos , Hemofilia A/diagnóstico , Hemofilia A/tratamento farmacológico , Hemofilia A/genética , Qualidade de Vida , Hemorragia , Inquéritos e Questionários
3.
N Engl J Med ; 388(8): 706-718, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36812434

RESUMO

BACKGROUND: Moderate-to-severe hemophilia B is treated with lifelong, continuous coagulation factor IX replacement to prevent bleeding. Gene therapy for hemophilia B aims to establish sustained factor IX activity, thereby protecting against bleeding without burdensome factor IX replacement. METHODS: In this open-label, phase 3 study, after a lead-in period (≥6 months) of factor IX prophylaxis, we administered one infusion of adeno-associated virus 5 (AAV5) vector expressing the Padua factor IX variant (etranacogene dezaparvovec; 2×1013 genome copies per kilogram of body weight) to 54 men with hemophilia B (factor IX activity ≤2% of the normal value) regardless of preexisting AAV5 neutralizing antibodies. The primary end point was the annualized bleeding rate, evaluated in a noninferiority analysis comparing the rate during months 7 through 18 after etranacogene dezaparvovec treatment with the rate during the lead-in period. Noninferiority of etranacogene dezaparvovec was defined as an upper limit of the two-sided 95% Wald confidence interval of the annualized bleeding rate ratio that was less than the noninferiority margin of 1.8. Superiority, additional efficacy measures, and safety were also assessed. RESULTS: The annualized bleeding rate decreased from 4.19 (95% confidence interval [CI], 3.22 to 5.45) during the lead-in period to 1.51 (95% CI, 0.81 to 2.82) during months 7 through 18 after treatment, for a rate ratio of 0.36 (95% Wald CI, 0.20 to 0.64; P<0.001), demonstrating noninferiority and superiority of etranacogene dezaparvovec as compared with factor IX prophylaxis. Factor IX activity had increased from baseline by a least-squares mean of 36.2 percentage points (95% CI, 31.4 to 41.0) at 6 months and 34.3 percentage points (95% CI, 29.5 to 39.1) at 18 months after treatment, and usage of factor IX concentrate decreased by a mean of 248,825 IU per year per participant in the post-treatment period (P<0.001 for all three comparisons). Benefits and safety were observed in participants with predose AAV5 neutralizing antibody titers of less than 700. No treatment-related serious adverse events occurred. CONCLUSIONS: Etranacogene dezaparvovec gene therapy was superior to prophylactic factor IX with respect to the annualized bleeding rate, and it had a favorable safety profile. (Funded by uniQure and CSL Behring; HOPE-B ClinicalTrials.gov number, NCT03569891.).


Assuntos
Fator IX , Terapia Genética , Hemofilia B , Humanos , Masculino , Fator IX/genética , Fator IX/uso terapêutico , Terapia Genética/métodos , Hemofilia B/complicações , Hemofilia B/genética , Hemofilia B/terapia , Hemorragia/etiologia , Hemorragia/terapia , Vetores Genéticos/administração & dosagem
4.
Hum Gene Ther ; 33(7-8): 432-441, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35156839

RESUMO

Adeno-associated virus (AAV)-mediated gene therapy may provide durable protection from bleeding events and reduce treatment burden for people with hemophilia A (HA). However, pre-existing immunity against AAV may limit transduction efficiency and hence treatment success. Global data on the prevalence of AAV serotypes are limited. In this global, prospective, noninterventional study, we determined the prevalence of pre-existing immunity against AAV2, AAV5, AAV6, AAV8, and AAVrh10 among people ≥12 years of age with HA and residual FVIII levels ≤2 IU/dL. Antibodies against each serotype were detected using validated, electrochemiluminescent-based enzyme-linked immunosorbent assays. To evaluate changes in antibody titers over time, 20% of participants were retested at 3 and 6 months. In total, 546 participants with HA were enrolled at 19 sites in 9 countries. Mean (standard deviation) age at enrollment was 36.0 (14.87) years, including 12.5% younger than 18 years, and 20.0% 50 years of age and older. On day 1, global seroprevalence was 58.5% for AAV2, 34.8% for AAV5, 48.7% for AAV6, 45.6% for AAV8, and 46.0% for AAVrh10. Considerable geographic variability was observed in the prevalence of pre-existing antibodies against each serotype, but AAV5 consistently had the lowest seroprevalence across the countries studied. AAV5 seropositivity rates were 51.8% in South Africa (n = 56), 46.2% in Russia (n = 91), 40% in Italy (n = 20), 37.2% in France (n = 86), 26.8% in the United States (n = 71), 26.9% in Brazil (n = 26), 28.1% in Germany (n = 89), 29.8% in Japan (n = 84), and 5.9% in the United Kingdom (n = 17). For all serotypes, seropositivity tended to increase with age. Serostatus and antibody titer were generally stable over the 6-month sampling period. As clinical trials of AAV-mediated gene therapies progress, data on the natural prevalence of antibodies against various AAV serotypes may become increasingly important.


Assuntos
Dependovirus , Hemofilia A , Anticorpos Neutralizantes , Anticorpos Antivirais , Dependovirus/genética , Vetores Genéticos/genética , Hemofilia A/epidemiologia , Hemofilia A/genética , Hemofilia A/terapia , Humanos , Estudos Prospectivos , Estudos Soroepidemiológicos , Sorogrupo
5.
Blood Coagul Fibrinolysis ; 33(2): 130-133, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34799506

RESUMO

We describe a case of a patient with multiple myeloma with initial presentation simulating a bleeding disorder. Detailed coagulation work-up showed hypodysfibrinogenaemia along with a platelet function defect consistent with acquired Bernard-Soulier syndrome (BSS). Multiple plasma exchanges led to significant improvement in his bleeding symptoms. To the best of our knowledge, this is the first described case of simultaneous presentation of hypodysfibrinogenaemia and BSS secondary to multiple myeloma.


Assuntos
Síndrome de Bernard-Soulier , Mieloma Múltiplo , Síndrome de Bernard-Soulier/complicações , Coagulação Sanguínea , Hemorragia , Humanos , Mieloma Múltiplo/complicações
6.
Cureus ; 13(7): e16764, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34476137

RESUMO

BACKGROUND:  The mortality of patients admitted to the intensive care unit (ICU) with COVID-19 remains significantly high. Severe COVID-19 pneumonia is characterised by refractory hypoxemia with significant shunting due to a combination of alveolar damage, vascular vasoconstriction, and occlusion due to microthrombi. Similar pathological features are seen in extra-pulmonary organs. However, the influence of thrombotic markers on the risk of mechanical ventilation (MV) and the development of acute kidney injury (AKI) is not fully defined. METHODS:  This was a cross-sectional evaluation of haemostatic and thrombotic markers of COVID-19 patients admitted to the ICU to determine their predictability for the development of thromboembolism and the need for non-invasive or invasive MV, development of AKI, and mortality. RESULTS:  An extended coagulation profile was obtained in 71 SARS-CoV-2 positive patients admitted to the ICU. All patients had acute severe hypoxic respiratory failure and required non-invasive or invasive MV. There were increases in peak D-dimer (3.0 mg/L), factor VIII levels (255 IU/dL) vWF antigen (471 IU/dL) with low ADAMTS13 activity (54.7 IU/dL) compared to the reference ranges. Peak D-dimer was consistently raised in patients who developed AKI and required invasive MV. ADAMTS13/vWF/platelet axis was associated with disease severity, multi-organ dysfunction, and mortality. CONCLUSIONS:  Haematological abnormalities are a common feature of severe COVID-19 pneumonia. We found peak D-dimer and vWF-ADAMTS13-platelet axis are associated with increased ICU severity and outcome in severe COVID-19 patients admitted to ICU. Larger studies are needed to evaluate this more comprehensively.

7.
Thromb Res ; 201: 100-112, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33662796

RESUMO

Thrombosis affecting the pulmonary and systemic vasculature is common during severe COVID-19 and causes adverse outcomes. Although thrombosis likely results from inflammatory activation of vascular cells, the mediators of thrombosis remain unconfirmed. In a cross-sectional cohort of 36 severe COVID-19 patients, we show that markedly increased plasma von Willebrand factor (VWF) levels were accompanied by a partial reduction in the VWF regulatory protease ADAMTS13. In all patients we find this VWF/ADAMTS13 imbalance to be associated with persistence of ultra-high-molecular-weight (UHMW) VWF multimers that are highly thrombogenic in some disease settings. Incubation of plasma samples from patients with severe COVID-19 with recombinant ADAMTS13 (rADAMTS13) substantially reduced the abnormally high VWF activity, reduced overall multimer size and depleted UHMW VWF multimers in a time and concentration dependent manner. Our data implicate disruption of normal VWF/ADAMTS13 homeostasis in the pathogenesis of severe COVID-19 and indicate that this can be reversed ex vivo by correction of low plasma ADAMTS13 levels. These findings suggest a potential therapeutic role for rADAMTS13 in helping restore haemostatic balance in COVID-19 patients.


Assuntos
COVID-19 , Proteínas Recombinantes , Trombose , Proteína ADAMTS13 , Estudos Transversais , Humanos , Proteínas Recombinantes/uso terapêutico , SARS-CoV-2 , Fator de von Willebrand
8.
Metabolomics ; 13(12): 145, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29104520

RESUMO

INTRODUCTION: Seed germination is inherently related to seed metabolism, which changes throughout its maturation, desiccation and germination processes. The metabolite content of a seed and its ability to germinate are determined by underlying genetic architecture and environmental effects during development. OBJECTIVE: This study aimed to assess an integrative approach to explore genetics modulating seed metabolism in different developmental stages and the link between seed metabolic- and germination traits. METHODS: We have utilized gas chromatography-time-of-flight/mass spectrometry (GC-TOF/MS) metabolite profiling to characterize tomato seeds during dry and imbibed stages. We describe, for the first time in tomato, the use of a so-called generalized genetical genomics (GGG) model to study the interaction between genetics, environment and seed metabolism using 100 tomato recombinant inbred lines (RILs) derived from a cross between Solanum lycopersicum and Solanum pimpinellifolium. RESULTS: QTLs were found for over two-thirds of the metabolites within several QTL hotspots. The transition from dry to 6 h imbibed seeds was associated with programmed metabolic switches. Significant correlations varied among individual metabolites and the obtained clusters were significantly enriched for metabolites involved in specific biochemical pathways. CONCLUSIONS: Extensive genetic variation in metabolite abundance was uncovered. Numerous identified genetic regions that coordinate groups of metabolites were detected and these will contain plausible candidate genes. The combined analysis of germination phenotypes and metabolite profiles provides a strong indication for the hypothesis that metabolic composition is related to germination phenotypes and thus to seed performance.

9.
N Engl J Med ; 377(9): 819-828, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28691885

RESUMO

BACKGROUND: Current hemophilia treatment involves frequent intravenous infusions of clotting factors, which is associated with variable hemostatic protection, a high treatment burden, and a risk of the development of inhibitory alloantibodies. Fitusiran, an investigational RNA interference (RNAi) therapy that targets antithrombin (encoded by SERPINC1), is in development to address these and other limitations. METHODS: In this phase 1 dose-escalation study, we enrolled 4 healthy volunteers and 25 participants with moderate or severe hemophilia A or B who did not have inhibitory alloantibodies. Healthy volunteers received a single subcutaneous injection of fitusiran (at a dose of 0.03 mg per kilogram of body weight) or placebo. The participants with hemophilia received three injections of fitusiran administered either once weekly (at a dose of 0.015, 0.045, or 0.075 mg per kilogram) or once monthly (at a dose of 0.225, 0.45, 0.9, or 1.8 mg per kilogram or a fixed dose of 80 mg). The study objectives were to assess the pharmacokinetic and pharmacodynamic characteristics and safety of fitusiran. RESULTS: No thromboembolic events were observed during the study. The most common adverse events were mild injection-site reactions. Plasma levels of fitusiran increased in a dose-dependent manner and showed no accumulation with repeated administration. The monthly regimen induced a dose-dependent mean maximum antithrombin reduction of 70 to 89% from baseline. A reduction in the antithrombin level of more than 75% from baseline resulted in median peak thrombin values at the lower end of the range observed in healthy participants. CONCLUSIONS: Once-monthly subcutaneous administration of fitusiran resulted in dose-dependent lowering of the antithrombin level and increased thrombin generation in participants with hemophilia A or B who did not have inhibitory alloantibodies. (Funded by Alnylam Pharmaceuticals; ClinicalTrials.gov number, NCT02035605 .).


Assuntos
Antitrombina III/antagonistas & inibidores , Hemofilia A/terapia , Hemofilia B/terapia , Terapêutica com RNAi , Adulto , Antitrombinas/sangue , Relação Dose-Resposta a Droga , Voluntários Saudáveis , Hemofilia A/sangue , Hemofilia B/sangue , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Trombina/biossíntese , Adulto Jovem
11.
Semin Thromb Hemost ; 41(6): 549-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26270112

RESUMO

Forming an interface with virtually every other organ, endothelium has a strategic role in modulating vascular homeostasis. While its miscellany of functions includes regulation of vasomotor tone, promotion, and prevention of vascular growth, and modulation of inflammatory and hemostatic processes, it functions critically in maintaining the balance of hemostasis in health. Whereas endothelium has been recognized to influence all stages of hemostasis, new evidence suggests it to have a primary role for thrombin generation. Endothelial dysfunction is being increasingly appreciated in several pathological states and particularly, by virtue of its critical role in hemostasis, in causing thrombosis in a multitude of diseases.


Assuntos
Endotélio Vascular/fisiologia , Hemostasia/fisiologia , Homeostase/fisiologia , Trombose/sangue , Animais , Antígenos CD/fisiologia , Células Endoteliais/patologia , Células Endoteliais/fisiologia , Receptor de Proteína C Endotelial , Endotélio Vascular/patologia , Hormônios/metabolismo , Humanos , Lipoproteínas/fisiologia , Comunicação Parácrina , Receptores de Superfície Celular/fisiologia , Trombina/biossíntese , Trombomodulina/fisiologia , Trombofilia/sangue , Trombofilia/etiologia , Trombofilia/patologia , Tromboplastina/fisiologia , Trombose/etiologia , Trombose/patologia , Fator de von Willebrand/fisiologia
12.
Semin Thromb Hemost ; 41(6): 665-72, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26305235

RESUMO

It is well established that inflammation and thrombosis are intricately linked processes, and there is increasing evidence of the importance of their roles in activated complement in the pathogenesis of thromboembolism. The two systems are activated by similar stimuli simultaneously and interact, either directly or through biochemical mediators, to protect the host from microbial invasion. Diseases characterized by complement hyperactivity such as paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome have high rates of thrombosis. This review describes how disease processes where there is excessive complement activation leads to thrombosis, and the specific interactions between the complement and coagulation systems that lead to pathological thrombus formation.


Assuntos
Ativação do Complemento/fisiologia , Inflamação/sangue , Tromboembolia/etiologia , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/imunologia , Fatores de Coagulação Sanguínea/fisiologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/complicações , Hemoglobinúria Paroxística/sangue , Hemoglobinúria Paroxística/complicações , Hemoglobinúria Paroxística/imunologia , Humanos , Imunidade Inata , Infecções/sangue , Infecções/imunologia , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Modelos Biológicos , Ativação Plaquetária , Tromboembolia/sangue , Tromboembolia/imunologia , Trombofilia/sangue , Trombofilia/etiologia , Microangiopatias Trombóticas/sangue , Microangiopatias Trombóticas/imunologia
13.
Adv Hematol ; 2015: 214680, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25810721

RESUMO

Impaired fibrinolysis may predispose to coronary artery disease (CAD). Hypofibrinolysis due to high levels of plasminogen activator inhibitor-1 (PAI-1) has been reported in CAD. A novel regulator of fibrinolytic activity, thrombin activatable fibrinolysis inhibitor (TAFI), has attracted attention in recent years. It acts by blocking the formation of a ternary complex of plasminogen, fibrin, and tissue plasminogen activator (t-PA). Previously ambiguous results regarding TAFI levels have been reported in CAD. We measured plasma levels of PAI-1 and TAFI antigen in 123 patients with age ranging from 40 to 65 years who had been submitted to coronary angiography and assessed the association of these markers with the extent of stenosis in three groups: angiographically normal artery (NAn), mild to moderate atheromatosis (MA), and severe atheromatosis (SA). Plasma levels of PAI-1 were increased in patients with severe atheromatosis compared to mild/moderate atheromatosis or to normal patients (66.60, 40.50, and 34.90 ng/mL, resp.; P < 0.001). For TAFI no difference was found between different groups. When patients were grouped in only two groups based on clinical cut-off point for intervention (stenosis less than or above 70%) we found increased plasma levels for PAI-1 (37.55 and 66.60 ng/mL, resp.; P < 0.001) and decreased plasma levels for TAFI (5.20 and 4.53 µg/mL, resp.; P = 0.04) in patients with stenosis above 70%. No difference was found in PAI-1 or TAFI levels comparing the number of affected vessels. Conclusion. As evidenced by a raised level of PAI-1 antigen, one can suggest an impaired fibrinolysis in stable CAD, although no correlation with the number of affected vessels was found. Curiously, a decreased plasma level of total TAFI levels was observed in patients with stenosis above 70%. Further studies measuring functional TAFI are required in order to elucidate its association with the extent of degree of atheromatosis.

14.
Blood Coagul Fibrinolysis ; 25(7): 671-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24806321

RESUMO

Preeclampsia (P-EC) is a multisystem disorder of pregnancy whose cause and pathogenesis remain poorly understood. However, abnormal haemostasis and endothelial dysfunction are thought to be implicated. Women with a past medical history of P-EC have a baseline hypercoagulable state postpregnancy. The aim of this study is to examine the relationship between tissue factor (TF) and TF pathway inhibitor (TFPI) in women who have had P-EC within the last 3 years (more than 6 months postpartum) and their normal counterparts. Blood specimens were collected from women known to have had P-EC within the last 3 years (n = 26) and aged-matched healthy women without past history of P-EC in previous pregnancy (n = 26). Plasma TF and TFPI levels were measured using ELISAs. Women who have had P-EC showed increased TF levels compared with their normal counterparts, whereas TFPI levels were reduced. Neither parameter differed significantly when the groups were tested against each other. Interestingly, the TF/TFPI ratio was significantly increased (P = 0.024) when the two groups were compared. In summary, there was a trend towards increased TF and reduced TFPI levels in the P-EC group. Such a tendency was not statistically significant. However, the TF/TFPI ratio was significantly increased when the groups were compared. Our findings suggest an imbalance between TF/TFPI levels in women with past history of P-EC postpregnancy. This may contribute to the development of maternal hypercoagulable states and may predispose women with a history of P-EC to cardiovascular risks later in life.


Assuntos
Lipoproteínas/sangue , Pré-Eclâmpsia/sangue , Trombofilia/sangue , Tromboplastina/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
15.
J Card Surg ; 28(4): 414-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23692692

RESUMO

Heyde syndrome (the combination of iron deficiency anemia and aortic stenosis) has been a controversial entity. The proposed mechanisms between aortic valve disease and iron deficiency anemia are examined in this article along with impact valve replacement on iron deficiency anemia.


Assuntos
Anemia Ferropriva/cirurgia , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Hemorragia Gastrointestinal/etiologia , Implante de Prótese de Valva Cardíaca , Idoso , Anemia Ferropriva/etiologia , Estenose da Valva Aórtica/etiologia , Bioprótese , Feminino , Humanos , Síndrome , Doenças de von Willebrand/etiologia
17.
PLoS One ; 7(8): e43991, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22952841

RESUMO

The success of germination, growth and final yield of every crop depends to a large extent on the quality of the seeds used to grow the crop. Seed quality is defined as the viability and vigor attribute of a seed that enables the emergence and establishment of normal seedlings under a wide range of environments. We attempt to dissect the mechanisms involved in the acquisition of seed quality, through a combined approach of physiology and genetics. To achieve this goal we explored the genetic variation found in a RIL population of Solanum lycopersicum (cv. Moneymaker) x Solanum pimpinellifolium through extensive phenotyping of seed and seedling traits under both normal and nutrient stress conditions and root system architecture (RSA) traits under optimal conditions. We have identified 62 major QTLs on 21 different positions for seed, seedling and RSA traits in this population. We identified QTLs that were common across both conditions, as well as specific to stress conditions. Most of the QTLs identified for seedling traits co-located with seed size and seed weight QTLs and the positive alleles were mostly contributed by the S. lycopersicum parent. Co-location of QTLs for different traits might suggest that the same locus has pleiotropic effects on multiple traits due to a common mechanistic basis. We show that seed weight has a strong effect on seedling vigor and these results are of great importance for the isolation of the corresponding genes and elucidation of the underlying mechanisms.


Assuntos
Plântula/crescimento & desenvolvimento , Plântula/genética , Sementes/crescimento & desenvolvimento , Sementes/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/genética , Epistasia Genética , Endogamia , Solanum lycopersicum/fisiologia , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Locos de Características Quantitativas , Plântula/fisiologia , Sementes/fisiologia , Especificidade da Espécie , Estresse Fisiológico
18.
Plant Cell Environ ; 35(5): 929-51, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22074055

RESUMO

Seed quality in tomato is associated with many complex physiological and genetic traits. While plant processes are frequently controlled by the action of small- to large-effect genes that follow classic Mendelian inheritance, our study suggests that seed quality is primarily quantitative and genetically complex. Using a recombinant inbred line population of Solanum lycopersicum × Solanum pimpinellifolium, we identified quantitative trait loci (QTLs) influencing seed quality phenotypes under non-stress, as well as salt, osmotic, cold, high-temperature and oxidative stress conditions. In total, 42 seed quality traits were analysed and 120 QTLs were identified for germination traits under different conditions. Significant phenotypic correlations were observed between germination traits under optimal conditions, as well as under different stress conditions. In conclusion, one or more QTLs were identified for each trait with some of these QTLs co-locating. Co-location of QTLs for different traits can be an indication that a locus has pleiotropic effects on multiple traits due to a common mechanistic basis. However, several QTLs also dissected seed quality in its separate components, suggesting different physiological mechanisms and signalling pathways for different seed quality attributes.


Assuntos
Variação Genética/genética , Locos de Características Quantitativas/genética , Sementes/fisiologia , Solanum lycopersicum/genética , Estresse Fisiológico/genética , Cruzamento , Mapeamento Cromossômico , Cromossomos de Plantas , Temperatura Baixa , Epistasia Genética , Transferência Genética Horizontal , Genótipo , Germinação/fisiologia , Temperatura Alta , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/fisiologia , Pressão Osmótica , Estresse Oxidativo , Fenótipo , Sementes/efeitos dos fármacos , Sementes/genética , Cloreto de Sódio/farmacologia
20.
Blood Coagul Fibrinolysis ; 22(7): 600-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21934489

RESUMO

The association between type 2 diabetes and cardiovascular disease is long recognized. Although perturbations of haemostatic markers have been shown to be associated with macrovascular disease in patients with type 2 diabetes, it is unclear whether these are primarily due to endothelial dysfunction or a result of inflammation. The present study was undertaken to elucidate whether elevated levels of factor VIII (FVIII) and von Willebrand factor (vWF) in women with type 2 diabetes represent endothelial dysfunction, inflammation or an alternate mechanism. Sixty-four women with type 2 diabetes were evaluated using ultrasonography Doppler for carotid intima-media thickness (IMT) and were classified as group A--having no (<1  mm), group B - mild (≥1  mm and no plaque) and group C--moderate (≥1 mm and presence of plaque and stenosis) macrovascular disease. Several haemostatic markers including, FVIII, vWF and fibrinogen were assessed. In addition, thrombomodulin, a marker for endothelial damage, and high-sensitivity C-reactive protein (hsCRP), an inflammatory marker, were also measured. A significant association of elevated FVIII was found in group B and C patients (i.e. patients with IMT ≥1 mm and with plaque). Elevated fibrinogen and vWF levels were also found but confined to group C patients. No significant difference among subgroups was found for any other variable evaluated (hsCRP, thrombomodulin and FVII). In conclusion, plasma FVIII levels are elevated in women with type 2 diabetes and macrovascular disease. It also appears that this is not mediated by inflammation or endothelial injury and is likely to be due to an alternate mechanism.


Assuntos
Doenças Cardiovasculares/sangue , Diabetes Mellitus Tipo 2/sangue , Endotélio Vascular/metabolismo , Fator VIII/metabolismo , Inflamação/sangue , Fator de von Willebrand/metabolismo , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/fisiopatologia , Espessura Intima-Media Carotídea , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/diagnóstico por imagem , Endotélio Vascular/fisiopatologia , Feminino , Fibrinogênio/metabolismo , Humanos , Inflamação/diagnóstico por imagem , Inflamação/fisiopatologia , Pessoa de Meia-Idade , Trombomodulina/sangue , Túnica Íntima/anatomia & histologia , Túnica Íntima/diagnóstico por imagem , Ultrassonografia Doppler em Cores
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