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2.
J Thromb Haemost ; 20(12): 2896-2908, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36107495

RESUMO

BACKGROUND: Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare complication of adenovirus-based vaccines aimed to prevent and minimize COVID-19 and related pathophysiology. OBJECTIVES: To describe patterns of testing for anti-platelet factor 4 (PF4) antibodies using various ELISA assays in a large Australian cohort and comparative functional platelet activation assays in a subset. PATIENTS/METHODS: Asserachrom HPIA IgG ELISA was performed in 1284 patients over a period of 12 months, supplemented in select cohorts by comparative ELISA using three other methods (n = 78-179), three different functional assays (flow cytometry, serotonin release assay, and/or Multiplate; n = 476), and rapid immunological chemiluminescence anti-PF4 assay (n = 460), in a multicenter study. RESULTS: For first episode presentations, 190/1284 (14.8%) ELISA tests were positive. Conversely, most (445/460; 96.7%) chemiluminescence anti-PF4 test results were negative. All functional assays showed associations of higher median ELISA optical density with functional positivity and with high rates of ELISA positivity (64.0% to 85.2%). Data also identified functional positivity in 14.8%-36.0% of ELISA negative samples, suggesting false negative VITT by HPIA IgG ELISA in upward of one third of assessable cases. CONCLUSION: To our knowledge, this is the largest multicenter evaluation of anti-PF4 testing for investigation of VITT. Discrepancies in test results (ELISA vs. ELISA or ELISA vs. functional assay) in some patients highlighted limitations in relying on single methods (ELISA and functional) for PF4 antibody detection in VITT, and also highlights the variability in phenotypic test presentation and pathomechanism of VITT.


Assuntos
COVID-19 , Trombocitopenia , Trombose , Vacinas , Humanos , Fator Plaquetário 4 , Heparina/efeitos adversos , Austrália , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnóstico , Trombose/diagnóstico , Fatores Imunológicos/efeitos adversos , Imunoglobulina G
3.
Vaccine ; 40(40): 5781-5790, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36055874

RESUMO

The global burden of malaria remains substantial. Circumsporozoite protein (CSP) has been demonstrated to be an effective target antigen, however, improvements that offer more efficacious and more durable protection are still needed. In support of research and development of next-generation malaria vaccines, Walter Reed Army Institute of Research (WRAIR) has developed a CSP-based antigen (FMP013) and a novel adjuvant ALFQ (Army Liposome Formulation containing QS-21). We present a single center, open-label, dose-escalation Phase 1 clinical trial to evaluate the safety and immunogenicity of the FMP013/ALFQ malaria vaccine candidate. In this first-in-human evaluation of both the antigen and adjuvant, we enrolled ten subjects; five received 20 µg FMP013 / 0.5 mL ALFQ (Low dose group), and five received 40 µg FMP013 / 1.0 mL ALFQ (High dose group) on study days 1, 29, and 57. Adverse events and immune responses were assessed during the study period. The clinical safety profile was acceptable and there were no serious adverse events. Both groups exhibited robust humoral and cellular immunological responses, and compared favorably with historical responses reported for RTS,S/AS01. Based on a lower reactogenicity profile, the 20 µg FMP013 / 0.5 mL ALFQ (Low dose) was selected for follow-on efficacy testing by controlled human malaria infection (CHMI) with a separate cohort. Trial Registration:Clinicaltrials.gov Identifier NCT04268420 (Registered February 13, 2020).


Assuntos
Vacinas Antimaláricas , Malária Falciparum , Adjuvantes Imunológicos/efeitos adversos , Adulto , Anticorpos Antiprotozoários , Humanos , Malária Falciparum/prevenção & controle , Plasmodium falciparum , Proteínas de Protozoários
4.
Pathology ; 53(2): 247-256, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33032809

RESUMO

Heparin induced thrombocytopenia (HIT) is a rare but potentially fatal complication of heparin therapy. In some patients, HIT causes platelet activation and thrombosis (sometimes abbreviated HITT), which leads to adverse clinical sequalae ('pathological HIT'). The likelihood of HIT is initially assessed clinically, typically using a scoring system, of which the 4T score is that most utilised. Subsequent laboratory testing to confirm or exclude HIT facilitates exclusion or diagnosis and management. The current investigation comprises a multicentre (n=9) assessment of contemporary laboratory testing for HIT, as performed over the past 1-3 years in each site and comprising testing of over 1200 samples. The primary laboratory test used by study participants (n=8) comprised a chemiluminescence procedure (HIT-IgG(PF4-H)) performed on an AcuStar instrument. Additional immunological testing performed by study sites included lateral flow (STiC, Stago), enzyme linked immunosorbent assay (ELISA), Asserachrom (HPIA IgG), PaGIA (BioRad), plus functional assays, primarily serotonin release assay (SRA) or platelet aggregation methods. The chemiluminescence procedure yielded a highly sensitive screening method for identifying functional HIT, given high area under the curve (AUC, generally ≥0.9) in a receiver operator characteristic (ROC) analysis against SRA as gold standard. ELISA testing resulted in lower ROC AUC scores (<0.8) and higher levels of false positives. Although there is clear association with the likelihood of HIT, the 4T score had less utility than literature suggests, and was comparable to a previous study reported by some of the authors.


Assuntos
Testes Diagnósticos de Rotina/métodos , Heparina/efeitos adversos , Trombocitopenia/diagnóstico , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Heparina/uso terapêutico , Humanos , Laboratórios Hospitalares , Masculino , Agregação Plaquetária , Curva ROC , Trombocitopenia/etiologia , Trombose/induzido quimicamente
5.
J Thromb Haemost ; 19(2): 417-428, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33124748

RESUMO

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare but potentially fatal disorder caused by ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) deficiency. Prompt identification/exclusion of TTP can thus be facilitated by rapid ADAMTS13 testing. The most commonly utilized (enzyme-linked immunosorbent assay [ELISA]-based) assay takes several hours to perform and so does not generally permit rapid testing. OBJECTIVES: To evaluate the utility of a new automated test for ADAMTS13 activity, the HemosIL AcuStar ADAMTS13 Activity assay, based on chemiluminescence and able to be performed on an ACL AcuStar instrument within 33 minutes. PATIENTS/METHODS: This multicenter (n = 8) assessment included testing of more than 700 test samples, with similar numbers of prospective (n = 348) and retrospective (n = 385) samples. The main comparator was the Technozym ADAMTS13 Activity ELISA. We also assessed comparative performance for detection of ADAMTS13 inhibitors using a Bethesda assay. RESULTS: Overall, the chemiluminescent assay yielded similar results to the comparator ELISA, albeit with slight negative bias. ADAMTS13 inhibitor detection was also comparable, albeit with slight positive bias with the AcuStar assay. Assay precision was similar with both assays, and we also verified assay normal reference ranges. CONCLUSIONS: The HemosIL AcuStar ADAMTS13 Activity assay provided results rapidly, which were largely comparable with the Technozym ADAMTS13 Activity ELISA assay, albeit lower on average. Conversely, inhibitor levels tended to be identified at a higher level on average. Thus, the HemosIL AcuStar ADAMTS13 Activity assay provides a fast and accurate means to quantitate plasma levels of ADAMTS13 for TTP/ADAMTS13 identification/exclusion, and potentially also for other applications.


Assuntos
Laboratórios , Púrpura Trombocitopênica Trombótica , Proteína ADAMTS13 , Humanos , Medições Luminescentes , Estudos Prospectivos , Púrpura Trombocitopênica Trombótica/diagnóstico , Estudos Retrospectivos
6.
Health Promot Int ; 35(3): 449-457, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31056656

RESUMO

Notwithstanding the historical benefits of coal in aiding human and economic development, the negative health and environmental impacts of coal extraction and processing are of increasing concern. Environmental impact assessments (EIAs) are a regulated policy mechanism that can be used to predict and consider the health impacts of mining projects to determine if consent is given. The ways in which health is considered within EIA is unclear. This research investigated 'How and to what extent are health, well-being and equity issues considered in Environmental Impact Assessments (EIAs) of major coal mining projects in New South Wales, Australia'. To this end we developed and applied a comprehensive coding framework designed to interrogate the publicly available environmental impact statements (EISs) of three mines in New South Wales (NSW), Australia, for their inclusion of health, well-being and equity issues. Analysis of the three EISs demonstrates that: the possible impacts of each mine on health and well-being were narrowly and inadequately considered; when health and well-being were considered there was a failure to assess the possible impacts specific to the particular mine and the communities potentially affected; the cumulative impacts on human health of multiple mines in the same geographical area were almost completely ignored; the discussions of intragenerational and intergenerational equity did not demonstrate a sound understanding of equity and, it is essential that governments' requirements for the EIA include detailed analysis of the health, well-being, equity and cumulative impacts specific to the proposed mine and relevant communities.


Assuntos
Minas de Carvão , Equidade em Saúde , Avaliação do Impacto na Saúde/métodos , Meio Ambiente , Humanos , New South Wales
7.
Genome Biol ; 16: 76, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25908251

RESUMO

BACKGROUND: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. RESULTS: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. CONCLUSIONS: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation.


Assuntos
Abelhas/genética , Comportamento Animal , Genes de Insetos , Comportamento Social , Animais , Venenos de Abelha/genética , Abelhas/classificação , Abelhas/fisiologia , Células Quimiorreceptoras/metabolismo , Mapeamento Cromossômico , Bases de Dados Genéticas , Evolução Molecular , Feminino , Regulação da Expressão Gênica , Rearranjo Gênico , Genômica , Sequências Repetitivas Dispersas , Masculino , Fases de Leitura Aberta , Polimorfismo de Nucleotídeo Único , Selenoproteínas/genética , Selenoproteínas/metabolismo , Análise de Sequência de DNA , Especificidade da Espécie , Sintenia
8.
Mcgill J Med ; 12(2): 39, 2009 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-21152332

RESUMO

Exposure to mercury from environmental sources, such as fish consumption, poses potential health risks to the public. The state of Vermont has developed educational brochures and posters displaying safe fish consumption guidelines in order to educate the public regarding mercury exposure through fish. In this study, a group of medical students from the University of Vermont College of Medicine, in partnership with the Vermont Department of Health, conducted a study in Chittenden County, Vermont in order to assess both fish consumption practices and overall awareness of such safe eating guidelines and mercury advisories. A total of 166 Vermont residents were surveyed during a six week period. The results of this survey suggest that in Chittenden county of Vermont, these educational efforts are markedly successful, with 48% of respondents being specifically aware of the safe eating guidelines. Further, these results suggest that 61% of those respondents that reported low monthly canned tuna consumption had a decreased their consumption in response to the safe eating guidelines. last, a series of specific, yet widely applicable recommendations are presented for future public educational efforts regarding mercury exposure through fish consumption.

9.
Thromb Haemost ; 87(3): 466-76, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11916080

RESUMO

Five expert laboratories have participated in a cross-laboratory study to co-evaluate and compare three commercial Factor VIII/von Willebrand factor (VWF) concentrates. A total of nine factor concentrate lots were evaluated, comprising AHF (High Purity) (AHF HP; x3), Biostate (x3) and Humate/Haemate (x3). All laboratories blind tested for FVIII: C, VWF: Ag and VWF: CB, four tested for VWF: RCo, and one performed VWF: Multimers. The study yielded inter-laboratory CVs for VWF: Ag and FVIII:C around 10-15%, and for VWF:CB and VWF:RCo around 20%, significantly lower than those of previous multi-laboratory surveys. All three lots of AHF HP contained in the vicinity of 25 U/ml FVIII:C, around 60-75 U/ml of VWF:Ag, but only 30-45 U/ml of VWF:CB and 40-50 U/ml of VWF:RCo (thus, CB/Ag ratio around 0.5-0.6 and RCo/Ag ratio around 0.6-0.7). Study determined that FVIII: C and VWF: RCo levels were similar to manufacturer assigned levels. Some loss of the high molecular weight (HMW) multimers was observed, together with an intense low molecular weight (LMW) VWF band consistent with some reduction or proteolysis of HMW VWF. All three lots of Humate/Haemate contained in the vicinity of 23-32 U/ml of FVIII:C, 70-105 U/ml of VWF: Ag, 50-90 U/ml of VWF: CB and VWF: RCo (i.e. CB/Ag ratio around 0.6-0.9 and RCo/Ag ratio around 0.6-1.1). Study-determined FVIII: C and VWF: RCo levels were similar to manufacturer-assigned levels. The LMW multimer band seen with AHF HP was also observed with Humate/Haemate. All three lots of Biostate contained in the vicinity of 40-55 U/ml of FVIII:C, 105-170 U/ml of VWF:Ag, 90-150 U/ml of VWF:CB, and 90-135 U/ml of VWF:RCo (i.e. CB/Ag and RCo/Ag ratios around 0.7-1.0). Study-determined FVIII:C levels were similar to manufacturer-assigned levels. The LMW multimer band seen with AHF HP was not observed with Biostate. The defined pattern of increasing CB/ Ag from AHF HP to Humate/Haemate and Biostate was consistently observed in study data from each of the five laboratories. In conclusion, study findings indicate some differences in the retention of functional/ HMW VWF between factor concentrates, and this is expected to have significant implications in terms of clinical efficacy for therapy in VWD.


Assuntos
Fator VIII/normas , Fator de von Willebrand/normas , Dimerização , Avaliação de Medicamentos , Fator VIII/análise , Humanos , Peso Molecular , Variações Dependentes do Observador , Padrões de Referência , Fator de von Willebrand/análise
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