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1.
Plant Mol Biol ; 114(3): 65, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816532

RESUMO

Telomeres are conserved chromosomal structures necessary for continued cell division and proliferation. In addition to the classical telomerase pathway, multiple other genes including those involved in ribosome metabolism and chromatin modification contribute to telomere length maintenance. We previously reported that Arabidopsis thaliana ribosome biogenesis genes OLI2/NOP2A, OLI5/RPL5A and OLI7/RPL5B have critical roles in telomere length regulation. These three OLIGOCELLULA genes were also shown to function in cell proliferation and expansion control and to genetically interact with the transcriptional co-activator ANGUSTIFOLIA3 (AN3). Here we show that AN3-deficient plants progressively lose telomeric DNA in early homozygous mutant generations, but ultimately establish a new shorter telomere length setpoint by the fifth mutant generation with a telomere length similar to oli2/nop2a -deficient plants. Analysis of double an3 oli2 mutants indicates that the two genes are epistatic for telomere length control. Telomere shortening in an3 and oli mutants is not caused by telomerase inhibition; wild type levels of telomerase activity are detected in all analyzed mutants in vitro. Late generations of an3 and oli mutants are prone to stem cell damage in the root apical meristem, implying that genes regulating telomere length may have conserved functional roles in stem cell maintenance mechanisms. Multiple instances of anaphase fusions in late generations of oli5 and oli7 mutants were observed, highlighting an unexpected effect of ribosome biogenesis factors on chromosome integrity. Overall, our data implicate AN3 transcription coactivator and OLIGOCELLULA proteins in the establishment of telomere length set point in plants and further suggest that multiple regulators with pleiotropic functions can connect telomere biology with cell proliferation and cell expansion pathways.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Divisão Celular , Telomerase , Telômero , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Telômero/genética , Telômero/metabolismo , Divisão Celular/genética , Telomerase/genética , Telomerase/metabolismo , Homeostase do Telômero/genética , Regulação da Expressão Gênica de Plantas , Mutação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proliferação de Células/genética , Meristema/genética , Meristema/metabolismo
2.
Plant Cell ; 33(4): 1118-1134, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-33580702

RESUMO

Telomeres are highly repetitive DNA sequences found at the ends of chromosomes that protect the chromosomes from deterioration duringcell division. Here, using whole-genome re-sequencing and terminal restriction fragment assays, we found substantial natural intraspecific variation in telomere length in Arabidopsis thaliana, rice (Oryza sativa), and maize (Zea mays). Genome-wide association study (GWAS) mapping in A. thaliana identified 13 regions with GWAS-significant associations underlying telomere length variation, including a region that harbors the telomerase reverse transcriptase (TERT) gene. Population genomic analysis provided evidence for a selective sweep at the TERT region associated with longer telomeres. We found that telomere length is negatively correlated with flowering time variation not only in A. thaliana, but also in maize and rice, indicating a link between life-history traits and chromosome integrity. Our results point to several possible reasons for this correlation, including the possibility that longer telomeres may be more adaptive in plants that have faster developmental rates (and therefore flower earlier). Our work suggests that chromosomal structure itself might be an adaptive trait associated with plant life-history strategies.


Assuntos
Flores/fisiologia , Variação Genética , Fenômenos Fisiológicos Vegetais/genética , Telômero/genética , Arabidopsis/genética , Tamanho do Genoma , Genoma de Planta , Estudo de Associação Genômica Ampla , Oryza/genética , Seleção Genética , Sequências de Repetição em Tandem , Telomerase/genética , Fatores de Tempo , Zea mays/genética
3.
Eur Respir J ; 60(4)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273032

RESUMO

BACKGROUND: Progressive fibrosing interstitial lung disease (PF-ILD) is characterised by progressive physiological, symptomatic and/or radiographic worsening. The real-world prevalence and characteristics of PF-ILD remain uncertain. METHODS: Patients were enrolled from the Canadian Registry for Pulmonary Fibrosis between 2015 and 2020. PF-ILD was defined as a relative forced vital capacity (FVC) decline ≥10%, death, lung transplantation or any two of: relative FVC decline ≥5% and <10%, worsening respiratory symptoms or worsening fibrosis on computed tomography of the chest, all within 24 months of diagnosis. Time-to-event analysis compared progression between key diagnostic subgroups. Characteristics associated with progression were determined by multivariable regression. RESULTS: Of 2746 patients with fibrotic ILD (mean±sd age 65±12 years; 51% female), 1376 (50%) met PF-ILD criteria in the first 24 months of follow-up. PF-ILD occurred in 427 (59%) patients with idiopathic pulmonary fibrosis (IPF), 125 (58%) with fibrotic hypersensitivity pneumonitis (HP), 281 (51%) with unclassifiable ILD (U-ILD) and 402 (45%) with connective tissue disease-associated ILD (CTD-ILD). Compared with IPF, time to progression was similar in patients with HP (hazard ratio (HR) 0.96, 95% CI 0.79-1.17), but was delayed in patients with U-ILD (HR 0.82, 95% CI 0.71-0.96) and CTD-ILD (HR 0.65, 95% CI 0.56-0.74). Background treatment varied across diagnostic subtypes, with 66% of IPF patients receiving antifibrotic therapy, while immunomodulatory therapy was utilised in 49%, 61% and 37% of patients with CHP, CTD-ILD and U-ILD, respectively. Increasing age, male sex, gastro-oesophageal reflux disease and lower baseline pulmonary function were independently associated with progression. CONCLUSIONS: Progression is common in patients with fibrotic ILD, and is similarly prevalent in HP and IPF. Routinely collected variables help identify patients at risk for progression and may guide therapeutic strategies.


Assuntos
Alveolite Alérgica Extrínseca , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Idoso , Alveolite Alérgica Extrínseca/complicações , Alveolite Alérgica Extrínseca/epidemiologia , Canadá/epidemiologia , Progressão da Doença , Feminino , Humanos , Fibrose Pulmonar Idiopática/complicações , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/epidemiologia , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Sistema de Registros
4.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563379

RESUMO

Chemical modifications in DNA impact gene regulation and chromatin structure. DNA oxidation, for example, alters gene expression, DNA synthesis and cell cycle progression. Modification of telomeric DNA by oxidation is emerging as a marker of genotoxic damage and is associated with reduced genome integrity and changes in telomere length and telomerase activity. 8-oxoguanine (8-oxoG) is the most studied and common outcome of oxidative damage in DNA. The G-rich nature of telomeric DNA is proposed to make it a hotspot for oxidation, but because telomeres make up only a tiny fraction of the genome, it has been difficult to directly test this hypothesis by studying dynamic DNA modifications specific to this region in vivo. Here, we present a new, robust method to differentially enrich telomeric DNA in solution, coupled with downstream methods for determination of chemical modification. Specifically, we measure 8-oxoG in Arabidopsis thaliana telomeres under normal and oxidative stress conditions. We show that telomere length is unchanged in response to oxidative stress in three different wild-type accessions. Furthermore, we report that while telomeric DNA comprises only 0.02-0.07% of the total genome, telomeres contribute between 0.2 and 15% of the total 8-oxoG. That is, plant telomeres accumulate 8-oxoG at levels approximately 100-fold higher than the rest of the genome under standard growth conditions. Moreover, they are the primary targets of further damage upon oxidative stress. Interestingly, the accumulation of 8-oxoG in the chromosome body seems to be inversely proportional to telomere length. These findings support the hypothesis that telomeres are hotspots of 8-oxoG and may function as sentinels of oxidative stress in plants.


Assuntos
Telomerase , Telômero , DNA/química , Dano ao DNA , Guanina/análogos & derivados , Guanina/química , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo
5.
Haemophilia ; 24 Suppl 6: 60-67, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29878660

RESUMO

Since the 1960s, the pace of innovation in haemophilia treatment has been fast and furious and occasionally with unintended consequences. As newer technologies are harnessed to better treat, and potentially cure, haemophilias A and B, an understanding of their underlying scientific principles and their benefits and risks are essential for all stakeholders. This review summarizes the starts and stops of introducing FVIII and FIX transgenes clinically, beginning 20 years ago. Lessons from earlier nonclinical and clinical experiments have been utilized to improve vector selection, vector design, promoter/enhancer cis control regions and codon-optimized transgenes to trigger in vivo clinical FVIII and FIX levels in the near-normal to normal ranges. Many known and unknown questions remain, and some, based upon benefit and risk, should be answered during larger phase 3 clinical trials. Prior clinical outcomes in haemophilia trials have not been standardized, making between-trial comparisons difficult. Going forward, haemophilia gene therapy clinical trials should utilize a standard set of core outcomes, to facilitate comparisons to other gene- and protein-based therapies. These outcomes will be more important as the field moves beyond the first-generation gene therapies into more complex vectors that may address the shortcomings of first-generation vectors and offer greater benefits to the patient.


Assuntos
Terapia Genética/métodos , Vetores Genéticos/genética , Hemofilia A/genética , Hemofilia A/terapia , Transgenes/genética , Animais , Fatores de Coagulação Sanguínea/genética , Humanos , Resultado do Tratamento
6.
Haemophilia ; 24 Suppl 6: 87-94, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29878652

RESUMO

INTRODUCTION: Information from the genes encoding factor VIII (F8) and IX (F9) is used in reproductive planning and to inform inhibitor formation, bleeding severity and response to therapies. Advances in technology and our understanding of the human genome now allows more comprehensive methods to study genomic variation and its impact on haemophilia. AIMS: The My Life Our Future (MLOF) programme was begun in 2012 to provide genetic analysis and to expand research in haemophilia through a research repository. METHODS: MLOF enrolled haemophilia A and B patients followed at haemophilia treatment centers in the U.S., including, since 2015, known and potential genetic carriers. Initial F8 and F9 DNA analysis was performed utilizing a next generation sequencing approach which allowed simultaneous detection of F8 inversions and other variants. Candidate variants were confirmed using a second method and multiplex ligation-dependent probe amplification was used to detect structural variants. RESULTS: The initial phase of MLOF completed enrollment in December 2017 with 11,356 patients, genetic carriers, and potential carriers enrolled. In the 9453 subjects in whom analysis is complete, 687 unique previously unreported variants were found. Simultaneous sequencing of the F8 and F9 genes resulted in identification of non-deleterious variants previously reported as causative in haemophilia. DNA from 5141 MLOF subjects has undergone whole genome sequencing through the NHLBI TOPMed programme of the U.S. NIH. CONCLUSION: MLOF has provided genetic information for patients and their families to help inform clinical care and has established a repository of data and biospecimens to further advance haemophilia research.


Assuntos
Genótipo , Hemofilia A/genética , Fenótipo , Sequenciamento Completo do Genoma/métodos , Hemofilia A/diagnóstico , Humanos , Prognóstico
7.
Haemophilia ; 24(2): 229-235, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29537123

RESUMO

INTRODUCTION: The gaps in haemophilia treatment around the world are enormous; approximately 60% of an estimated 475 000 individuals are not identified. Of the 187 000 diagnosed, 30% (57 000) access clotting factor replacement therapy. Since 1996, humanitarian aid distributed by the World Federation of Hemophilia (WFH) has played a minor, yet vital role providing life-saving clotting factor to countries in emergency situations. Donated amounts have been small and sporadic, often salvaging short-dated products, providing little opportunity to leverage donations with governments. In 2015, a prospective donation programme of 100 million I.U. per year of extended half-life factor VIII and IX over 10 years was established, necessitating the development of new logistics and training programmes by WFH. AIM: To measure the impact of a greatly expanded haemophilia humanitarian aid program. MATERIALS AND METHODS: In 2016, the first full year of the expanded programme, WFH, distributed products to 58 countries with factor VIII usage <1 I.U. per capita, a level incompatible with long-term survival and far below the 4 I.U. FVIII per capita minimum established in Europe. RESULTS: The scope of the programme and utilization data for 2016 indicate primarily use for acute bleeding, orthopaedic and emergency surgeries. Compared to 2014, 2016 data showed substantial increases in patients served (5.9-fold, from 2119 to 14 579), surgeries performed (37-fold) and bleeds treated (6.9-fold). Patients on prophylaxis rose from 0 to 852, including 458 children under 10 years old. DISCUSSION: The expanded humanitarian aid programme impacts an estimated 10% of individuals with haemophilia previously unable to access treatment. CONCLUSION: This programme represents an unprecedented public-private partnership to deliver medicines to individuals with no access. Further, the programme offers the prospective opportunity to engage governments to take more responsiblity for increasing training, medical management, and product supply in 58 resource constrained countries.


Assuntos
Hemofilia A/epidemiologia , Socorro em Desastres/organização & administração , Países em Desenvolvimento , Feminino , Humanos , Masculino
8.
Haemophilia ; 24(4): e167-e172, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29781145

RESUMO

BACKGROUND: Gene therapy trial results show potential to cure haemophilia A and haemophilia B. Securing broad access to a cure for a lifelong chronic disease is anticipated to face barriers at the individual and healthcare system levels, which can be partly mitigated by harmonized planning of clinical research studies. The aim of the coreHEM project was to determine the set of outcome measures required to evaluate efficacy, safety, comparative effectiveness and value of gene therapy for haemophilia. METHODS: Modified Delphi consensus process, based on methods adapted from the COMET Initiative. RESULTS: Forty-nine participants (five patients, five clinicians, five researchers, four regulators, three research agencies, six health technology assessors, nine payers and 12 drug developers) took part in the study, with over 90% participation. The frequency of bleeds, factor activity level, duration of expression, chronic pain, healthcare resource use and mental health were identified as the core outcomes to be measured in addition to regulatory-mandated adverse effects. CONCLUSIONS: For the first time in haemophilia, a core outcome set has been developed, with the involvement of representatives of all relevant stakeholder groups. The core set has been expanded to include outcomes supporting assessment of comparative effectiveness and value, with the goal of streamlining regulatory approval, health technology assessment and market access decisions. Patient involvement ensures that outcomes are meaningful and relevant to those living with haemophilia. Active dialogue among drug developers, regulators and payers throughout the process is expected to facilitate broad uptake of the core outcomes in forthcoming clinical trials.


Assuntos
Terapia Genética , Hemofilia A/terapia , Hemofilia B/terapia , Avaliação de Resultados em Cuidados de Saúde , Ensaios Clínicos como Assunto , Técnica Delphi , Terapia Genética/efeitos adversos , Hemofilia A/genética , Hemofilia B/genética , Humanos , Segurança
9.
Biochim Biophys Acta ; 1863(5): 999-1005, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26348128

RESUMO

Peroxisomes are dynamic, vital organelles that sequester a variety of oxidative reactions and their toxic byproducts from the remainder of the cell. The oxidative nature of peroxisomal metabolism predisposes the organelle to self-inflicted damage, highlighting the need for a mechanism to dispose of damaged peroxisomes. In addition, the metabolic requirements of plant peroxisomes change during development, and obsolete peroxisomal proteins are degraded. Although pexophagy, the selective autophagy of peroxisomes, is an obvious mechanism for executing such degradation, pexophagy has only recently been described in plants. Several recent studies in the reference plant Arabidopsis thaliana implicate pexophagy in the turnover of peroxisomal proteins, both for quality control and during functional transitions of peroxisomal content. In this review, we describe our current understanding of the occurrence, roles, and mechanisms of pexophagy in plants.


Assuntos
Proteases Dependentes de ATP/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Autofagia/genética , Peroxissomos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteases Dependentes de ATP/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Retículo Endoplasmático/química , Retículo Endoplasmático/metabolismo , Regulação da Expressão Gênica de Plantas , Oxirredução , Receptor 2 de Sinal de Orientação para Peroxissomos , Receptor 1 de Sinal de Orientação para Peroxissomos , Peroxissomos/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteólise , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais , Ubiquitinação
10.
Haemophilia ; 23(3): 392-399, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28220631

RESUMO

INTRODUCTION: The Phase 3 A-LONG study demonstrated the safety and efficacy of rFVIIIFc for the control and prevention of bleeding episodes in severe haemophilia A. AIM: To describe the treatment of bleeding episodes with rFVIIIFc in the A-LONG study. METHODS: A-LONG subjects (<1 IU dL-1 endogenous FVIII) were treated with individualized prophylaxis (Arm 1), weekly prophylaxis (Arm 2) or episodic treatment (Arm 3). Information recorded for each bleeding episode included type, location and dose to treat the episode. RESULTS: During A-LONG, 757 bleeding episodes occurred during the efficacy period; the majority [456 (60%)] occurred in Arm 3 (episodic treatment). Of 93 subjects in the prophylaxis arms who entered the study with target joints, 43 (60%) in Arm 1 and 11 (52%) in Arm 2 did not experience a target joint bleed. Overall, 98% of bleeding episodes (and 98% of bleeds involving a target joint) resolved with one or two infusions; the median dose per infusion to treat a bleed was 27 IU kg-1 (27 IU kg-1 for target joints). Using population pharmacokinetic simulations, FVIII activity levels were predicted to be below the upper limit of normal (150 IU dL-1 ) in most patients in the event that rFVIIIFc is used to treat a bleeding episode in close proximity to a prophylactic dose. CONCLUSIONS: These findings demonstrate the efficacy of rFVIIIFc for the treatment of acute bleeding episodes in subjects with severe haemophilia A, regardless of treatment regimen.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/complicações , Hemorragia/complicações , Hemorragia/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/genética , Proteínas Recombinantes de Fusão/uso terapêutico , Fator VIII/efeitos adversos , Fator VIII/farmacocinética , Feminino , Hemofilia A/prevenção & controle , Humanos , Masculino , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/farmacocinética , Segurança , Resultado do Tratamento
11.
Plant Cell ; 25(10): 4085-100, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24179123

RESUMO

Peroxisomes house critical metabolic reactions that are essential for seedling development. As seedlings mature, metabolic requirements change, and peroxisomal contents are remodeled. The resident peroxisomal protease LON2 is positioned to degrade obsolete or damaged peroxisomal proteins, but data supporting such a role in plants have remained elusive. Arabidopsis thaliana lon2 mutants display defects in peroxisomal metabolism and matrix protein import but appear to degrade matrix proteins normally. To elucidate LON2 functions, we executed a forward-genetic screen for lon2 suppressors, which revealed multiple mutations in key autophagy genes. Disabling core autophagy-related gene (ATG) products prevents autophagy, a process through which cytosolic constituents, including organelles, can be targeted for vacuolar degradation. We found that atg2, atg3, and atg7 mutations suppressed lon2 defects in auxin metabolism and matrix protein processing and rescued the abnormally large size and small number of lon2 peroxisomes. Moreover, analysis of lon2 atg mutants uncovered an apparent role for LON2 in matrix protein turnover. Our data suggest that LON2 facilitates matrix protein degradation during peroxisome content remodeling, provide evidence for the existence of pexophagy in plants, and indicate that peroxisome destruction via autophagy is enhanced when LON2 is absent.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Autofagia/genética , Peroxissomos/metabolismo , Proteólise , Serina Proteases/metabolismo , Aminopeptidases/genética , Aminopeptidases/metabolismo , Arabidopsis/enzimologia , Proteínas de Arabidopsis/genética , Proteínas Relacionadas à Autofagia , Ácidos Indolacéticos/metabolismo , Mutação , Serina Proteases/genética
12.
Haemophilia ; 22(6): 866-872, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27385432

RESUMO

INTRODUCTION: In haemophilia, prophylactic infusion of replacement factor can result in improvements in health-related quality of life (HRQoL) when compared with episodic treatment. The Haemophilia-specific Quality of Life (Haem-A-QoL) questionnaire assessed HRQoL in adults with severe haemophilia A or B who received prophylactic or episodic treatment with recombinant factor VIII or IX Fc fusion protein (rFVIIIFc or rFIXFc) in the A-LONG or B-LONG clinical studies. AIMS: Understand changes in HRQoL during the A-LONG and B-LONG trials. METHODS: Group-level and individual-level changes over time for the Haem-A-QoL key domains of 'Physical Health' and 'Sports & Leisure,' and 'Total Score' were evaluated in adults through baseline and 6-month HRQoL assessments. Previously determined responder definitions (RDs) were used for evaluating meaningful subject-level HRQoL improvements. RESULTS: The analysis included 67 A-LONG and 51 B-LONG subjects who completed the Haem-A-QoL (baseline and 6 months). While HRQoL improvements were observed among all treatment groups, greater improvements in HRQoL were observed among subjects who received episodic treatment pre-study (and prophylaxis on-study) compared to those who received hyphenate prophylaxis. Applying the RDs for interpreting 6-month changes, 47.4%/33.3% ('Physical Health'), 35.9%/50.0% ('Sports & Leisure') and 23.9%/33.3% ('Total Score') of A-LONG subjects who received individualized or weekly prophylaxis were classified as HRQoL responders. In B-LONG, 69.2%/57.9% ('Physical Health'), 44.4%/56.7% ('Sports & Leisure') and 41.7%/44.1% ('Total Score') of subjects who received individualized or weekly prophylaxis were classified as HRQoL responders. CONCLUSION: Changes in Haem-A-QoL key domains and 'Total Score' suggest that prophylaxis with long-acting rFVIIIFc or rFIXFc resulted in meaningful HRQoL improvements.


Assuntos
Fatores de Coagulação Sanguínea/uso terapêutico , Hemofilia A/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários , Adulto Jovem
13.
Haemophilia ; 22(1): 72-80, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26218032

RESUMO

INTRODUCTION: The safety, efficacy and prolonged half-life of recombinant factor VIII Fc fusion protein (rFVIIIFc) in previously treated patients with severe haemophilia A was demonstrated in the phase 3 A-LONG and Kids A-LONG studies. Here, we report interim safety and efficacy data from the rFVIIIFc extension study, ASPIRE (ClinicalTrials.gov #NCT01454739). METHODS: Eligible subjects could enrol in ASPIRE upon completing A-LONG or Kids A-LONG. There were four treatment groups: individualized prophylaxis; weekly prophylaxis; modified prophylaxis (for subjects in whom optimal treatment could not be achieved with individualized or weekly prophylaxis); and episodic treatment. The primary endpoint was development of inhibitors. RESULTS: A total of 150 A-LONG subjects and 61 Kids A-LONG subjects enrolled in ASPIRE. As of the interim data cut (6 January 2014), the median time on study was 80.9 (A-LONG) and 23.9 (Kids A-LONG) weeks. The majority of subjects (A-LONG, 92.0%; Kids A-LONG, 57.4%) had ≥100 cumulative rFVIIIFc exposure days. No inhibitors were observed. Adverse events were generally consistent with those expected in the general haemophilia A population. Median annualized bleeding rates (ABRs) were low with individualized [A-LONG: 0.66; Kids A-LONG: 0.00 (<6 years old), 1.54 (6 to <12 years old)], weekly (A-LONG: 2.03) and modified (A-LONG: 1.97) prophylaxis. There was no change in prophylactic infusion frequency or total weekly prophylactic dose in the majority of subjects from A-LONG and Kids A-LONG. CONCLUSION: Interim data from ASPIRE confirm the long-term safety of rFVIIIFc and the maintenance of a low ABR with extended-interval prophylactic dosing in patients with severe haemophilia A.


Assuntos
Fator VIII/efeitos adversos , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/uso terapêutico , Segurança , Criança , Pré-Escolar , Feminino , Hemofilia A/complicações , Hemofilia A/prevenção & controle , Hemofilia A/cirurgia , Hemorragia/complicações , Humanos , Masculino , Assistência Perioperatória
14.
Parasitol Res ; 114(6): 2143-54, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25810220

RESUMO

Spawning individuals of allis shad, Alosa alosa (Linnaeus, 1758), and twaite shad, Alosa fallax (Lacépède, 1803), were sampled from three rivers on the Atlantic coast of the Iberian Peninsula (Ulla, Minho, Mondego) during 2008 to 2013 to assess the presence of the zoonotic marine parasite Anisakis spp. larvae. The results revealed that both shad species were infected by third-larval stage Anisakis simplex s.s. and Anisakis pegreffii. The latter is reported in mixed infections in both shad species of Western Iberian Peninsula for the first time. In A. alosa, the prevalence of Anisakis infection can reach 100%, while in A. fallax, prevalence was up to 83%. Infected individuals of the former species also often contain much higher number of parasites in theirs internal organs and flesh: from 1 to 1138 Anisakis spp. larvae as compared to 1 to 121 larvae, respectively. In general, numbers of A. pegreffii were higher than those of A. simplex s.s. Our results suggest that in the marine environment of the Western Iberian Peninsula, both anadromous shad species act as paratenic hosts for A. simplex s.s. and A. pegreffii, thus widening the distribution of the infective nematode larvae from the marine to the freshwater ecosystem. This finding is of great epidemiological relevance for wildlife managers and consumers, considering the zoonotic and gastroallergic threats posed of these parasites.


Assuntos
Anisakis/isolamento & purificação , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Animais , Ecossistema , Doenças dos Peixes/epidemiologia , Humanos , Larva , Portugal/epidemiologia , Rios , Espanha/epidemiologia , Zoonoses
15.
Haemophilia ; 20(4): e327-35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24811361

RESUMO

Recombinant factor IX Fc (rFIXFc) fusion protein is the first of a new class of bioengineered long-acting factors approved for the treatment and prevention of bleeding episodes in haemophilia B. The aim of this work was to describe the manufacturing process for rFIXFc, to assess product quality and to evaluate the capacity of the process to remove impurities and viruses. This manufacturing process utilized a transferable and scalable platform approach established for therapeutic antibody manufacturing and adapted for production of the rFIXFc molecule. rFIXFc was produced using a process free of human- and animal-derived raw materials and a host cell line derived from human embryonic kidney (HEK) 293H cells. The process employed multi-step purification and viral clearance processing, including use of a protein A affinity capture chromatography step, which binds to the Fc portion of the rFIXFc molecule with high affinity and specificity, and a 15 nm pore size virus removal nanofilter. Process validation studies were performed to evaluate identity, purity, activity and safety. The manufacturing process produced rFIXFc with consistent product quality and high purity. Impurity clearance validation studies demonstrated robust and reproducible removal of process-related impurities and adventitious viruses. The rFIXFc manufacturing process produces a highly pure product, free of non-human glycan structures. Validation studies demonstrate that this product is produced with consistent quality and purity. In addition, the scalability and transferability of this process are key attributes to ensure consistent and continuous supply of rFIXFc.


Assuntos
Fator IX/genética , Fragmentos Fc das Imunoglobulinas/genética , Engenharia de Proteínas/métodos , Proteínas Recombinantes de Fusão/genética , Células HEK293 , Humanos , Segurança , Vírus/isolamento & purificação
16.
Haemophilia ; 20(2): 294-300, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24261554

RESUMO

Discrepancies exist for some of the modified coagulation factors when assayed with different one-stage clotting and chromogenic substrate assay reagents. The aim of this study was to evaluate the performance of a recombinant factor VIII Fc fusion protein (rFVIIIFc), currently in clinical development for the treatment of severe haemophilia A, in a variety of one-stage clotting and chromogenic substrate assays in clinical haemostasis laboratories. Haemophilic plasma samples spiked with rFVIIIFc or Advate(®) at 0.05, 0.20 or 0.80 IU mL(-1) were tested by 30 laboratories using their routine procedures and plasma standards. Data were evaluated for intra- and inter-laboratory variation, accuracy and possible rFVIIIFc-specific assay discrepancies. For the one-stage assay, mean recovery was 95% to 100% of expected for both Advate(®) and rFVIIIFc at 0.8 IU mL(-1). Intra-laboratory percent coefficient of variance (CV) ranged from 6.3% to 7.8% for Advate(®), and 6.0% to 10.3% for rFVIIIFc. Inter-laboratory CV ranged from 10% for Advate(®) and 16% for rFVIIIFc at 0.8 IU mL(-1), to over 30% at 0.05 IU mL(-1) for both products. For the chromogenic substrate assay, the average FVIII recovery was 107% ± 5% and 124% ± 8% of label potency across the three concentrations of Advate(®) and rFVIIIFc, respectively. Plasma rFVIIIFc levels can be monitored by either the one-stage or the chromogenic substrate assay routinely performed in clinical laboratories without the need for a product-specific rFVIIIFc laboratory standard. Accuracy by the one-stage assay was comparable to that of Advate(®), while marginally higher results may be observed for rFVIIIFc when using the chromogenic assay.


Assuntos
Testes de Coagulação Sanguínea/métodos , Fator VIII/metabolismo , Hemofilia A/sangue , Proteínas Recombinantes/sangue , Testes de Coagulação Sanguínea/normas , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Humanos , Kit de Reagentes para Diagnóstico , Proteínas Recombinantes/uso terapêutico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
J Microsc ; 251(2): 154-67, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23772985

RESUMO

We describe a microscopy design methodology and details of microscopes built to this 'open' design approach. These demonstrate the first implementation of time-domain fluorescence microscopy in a flexible automated platform with the ability to ease the transition of this and other advanced microscopy techniques from development to use in routine biology applications. This approach allows easy expansion and modification of the platform capabilities, as it moves away from the use of a commercial, monolithic, microscope body to small, commercial off-the-shelf and custom made modular components. Drawings and diagrams of our microscopes have been made available under an open license for noncommercial use at http://users.ox.ac.uk/~atdgroup. Several automated high-content fluorescence microscope implementations have been constructed with this design framework and optimized for specific applications with multiwell plates and tissue microarrays. In particular, three platforms incorporate time-domain FLIM via time-correlated single photon counting in an automated fashion. We also present data from experiments performed on these platforms highlighting their automated wide-field and laser scanning capabilities designed for high-content microscopy. Devices using these designs also form radiation-beam 'end-stations' at Oxford and Surrey Universities, showing the versatility and extendibility of this approach.


Assuntos
Biologia/métodos , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos , Automação Laboratorial/métodos
19.
J Fish Biol ; 83(4): 716-38, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24090545

RESUMO

This study demonstrates the utility of trawl data, collected during acoustic surveys of pelagic fish stocks as a way of confirming fish identification, to characterize the pelagic community, as well as allowing description and prediction of fish distribution patterns, based on data from Spanish Atlantic Ocean shelf surveys during spring 2005-2011. The composition of the pelagic community is described, as well as spatial and temporal patterns of variation in both the community composition and the presence and importance of two of the main exploited pelagic species, sardine Sardina pilchardus and anchovy Engraulis encrasicolus. The most important species in terms of both frequency of occurrence and standardized mass in hauls were mackerel Scomber scombrus, hake Merluccius merluccius, horse mackerel Trachurus trachurus, S. pilchardus and bogue Boops boops. Multivariate analysis indicated significant effects of depth, geographical area and year on haul composition. Descriptive generalized additive models (GAM), with latitude, longitude and depth as predictors, identified clear spatial patterns in the occurrence and abundance of both S. pilchardus and E. encrasicolus, with abundance being highest closer to the coast and, in the case of E. encrasicolus, higher near the French and Portuguese borders. Further GAM analysis, using environmental variables to explain spatial patterns, revealed significant effects of depth and sea surface temperature (SST) gradient and depth on S. pilchardus importance, while E. encrasicolus importance was related to SST. The importance of both species in hauls was higher in the years of higher spawning stock biomass (SSB) and E. encrasicolus also appeared to expand its range when SSB was higher.


Assuntos
Peixes , Gadiformes , Perciformes , Distribuição Animal , Animais , Oceano Atlântico , Biota , Conservação dos Recursos Naturais , Pesqueiros , Geografia , Modelos Biológicos , Espanha
20.
J Fish Biol ; 83(3): 480-500, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23991869

RESUMO

The behavioural effects of confinement of sardine Sardina pilchardus in a purse seine were evaluated through three laboratory experiments simulating the final stages of purse seining; the process of slipping (deliberately allowing fishes to escape) and subsequent exposure to potential predators. Effects of holding time (the time S. pilchardus were held or entangled in the simulation apparatus) and S. pilchardus density were investigated. Experiment 1 compared the effect of a mild fishing stressor (20 min in the net and low S. pilchardus density) with a control (fishing not simulated) while the second and third experiments compared the mild stressor with a severe stressor (40 min in the net and high S. pilchardus density). In all cases, sea bass Dicentrarchus labrax were used as potential predators. Results indicated a significant effect of crowding time and density on the survival and behaviour of slipped S. pilchardus. After simulated fishing, S. pilchardus showed significant behavioural changes including lower swimming speed, closer approaches to predators and higher nearest-neighbour distances (wider school area) than controls, regardless of stressor severity. These results suggest that, in addition to the delayed and unobserved mortality caused by factors related to fishing operations, slipped pelagic fishes can suffer behavioural impairments that may increase vulnerability to predation. Possible sub-lethal effects of behavioural impairment on fitness are discussed, with suggestions on how stock assessment might be modified to account for both unobserved mortality and sub-lethal effects, and possible approaches to provide better estimates of unobserved mortality in the field are provided.


Assuntos
Comportamento Animal , Peixes/fisiologia , Animais , Aglomeração , Comportamento Predatório , Estresse Fisiológico , Natação
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