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51.
Colaizzo D Amitrano L Iannaccone L Vergura P Cappucci F Grandone E Guardascione MA Margaglione M 《Journal of medical genetics》2007,44(6):412-416
Objective
To calculate the prevalence of common gain of function gene mutations in patients with different clinical manifestations of venous thromboembolism.Design and setting
Case–control study in two hospitals in Italy.Participants
387 patients with venous thromboembolism and 286 controls.Main measures
Factor V (FV) Leiden, factor II (FII) A20210 and JAK2 V617F mutations.Results
Among patients with deep vein thrombosis in one leg, 23 (20.9%) carried FV Leiden and FII A20210 mutations. Similar figures were observed in patients with cerebral vein thrombosis (CVT; n = 9; 20.0%) and in patients presenting with splanchnic vein thrombosis (SVT; n = 26; 18.7%). A lower prevalence was obtained in patients with retinal vein thrombosis (n = 11; 11.8%). The JAK2 F617 mutant allele was found in 27 (21.1%) patients with SVT, but in none of the patients presenting with a thrombotic event from different districts. 13 of the 27 JAK2 V617F‐positive subjects with SVT were previously known to have a myeloproliferative disease (MPD). Three other patients had a diagnosis of MPD after the occurrence of the thrombotic event.Conclusion
Carriership of FV Leiden or FII A20210 mutations identifies an at‐risk condition for venous thrombosis in the lower extremities, SVT or CVT. In patients with SVT, screening for the JAK2 V617F mutation may be useful in recognising patients who should be carefully observed for the subsequent development of overt MPD. Thus, genetic tests may play a different role, various clinical manifestations of venous thromboembolism being associated with distinct risk profiles.Venous thrombosis is the third most common cardiovascular affliction after ischaemic heart disease and stroke.1 It is common in Caucasians, affecting 1 in 1000 individuals every year, and is strongly associated with life‐threatening pulmonary embolism. The pathogenesis of venous thrombosis is multifactorial, involving acquired and genetic factors. In addition to circumstantial predisposing factors (eg, surgery, pregnancy, immobilisation and malignancy), genetic predisposition due to molecular abnormalities of components of the coagulation pathway have been found in subjects who had had thromboembolic disease.2 Abnormalities within the gene loci encoding for natural anticoagulants (antithrombin, protein C and protein S) and for fibrinogen have been shown to be rather uncommon risk factors for venous thrombosis.3 In patients of European ancestry, common gain‐of‐function mutations within the gene of the coagulation factor V (FV Leiden mutation) and the factor II (FII) gene (a G→A transition at nucleotide position 20210) have been shown to account for a large number of cases of thromboembolism.2,3 Recently, the JAK2 V617F mutation, an acquired somatic event occurring in most patients with polycythaemia vera (PV) and in about half of the patients with essential thrombocythaemia (ET) or myelofibrosis (MF),4,5,6,7,8 has been found in a high proportion of patients with Budd–Chiari syndrome9 and in patients without cirrhosis with portal and mesenteric venous thrombosis, a heterogeneous group of disorders.10Thus, the high frequency of common mutations in patients presenting with venous thromboembolism raised the hypothesis that it can be considered as a feasible and practical approach for the identification of predisposing genetic risk factors. Genetic test results can better inform individuals about their risk of recurrence and appropriated tailored strategies for the prevention of venous thrombosis.However, depending on the different clinical manifestations of venous thromboembolism, the prevalence of inherited coagulation abnormalities varies, suggesting pathogenic differences.11,12,13 These data support the hypothesis that mechanistic differences are involved in the pathogenesis of thrombosis in different clinical settings. Thus, before considering whether it is advisable to investigate a subject for inherited risk factors, we need to know the prevalence of these risk factors in different clinical settings.We, therefore, calculated the prevalence of inherited thrombophilic risk factors in a large cohort of patients referred for a thrombophilic investigation with different clinical manifestations of venous thromboembolism. 相似文献52.
Elsa D. Silva Pedro S. Babo Raquel Costa-Almeida Rui M.A. Domingues Bárbara B. Mendes Elvira Paz Paulo Freitas Márcia T. Rodrigues Pedro L. Granja Manuela E. Gomes 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(7):2375-2385
Photocrosslinkable magnetic hydrogels are attracting great interest for tissue engineering strategies due to their versatility and multifunctionality, including their remote controllability ex vivo, thus enabling engineering complex tissue interfaces. This study reports the development of a photocrosslinkable magnetic responsive hydrogel made of methacrylated chondroitin sulfate (MA-CS) enriched with platelet lysate (PL) with tunable features, envisioning their application in tendon-to-bone interface. MA-CS coated iron-based magnetic nanoparticles were incorporated to provide magnetic responsiveness to the hydrogel. Osteogenically differentiated adipose-derived stem cells and/or tendon-derived cells were encapsulated within the hydrogel, proliferating and expressing bone- and tendon-related markers. External magnetic field (EMF) application modulated the swelling, degradation and release of PL-derived growth factors, and impacted both cell morphology and the expression and synthesis of tendon- and bone-like matrix with a more evident effect in co-cultures. Overall, the developed magnetic responsive hydrogel represents a potential cell carrier system for interfacial tissue engineering with EMF-controlled properties. 相似文献
53.
Saúl Reveles‐Flix Rosalba Carren‐Npoles Susana Mendoza‐Elvira Víctor Quintero‐Ramírez Juvencio García‐Snchez Rebeca Martínez‐Bautista Manuel Saavedra‐Montaez Juan Joel Mosqueda Gualito Jos Ivan Snchez‐Betancourt 《Transboundary and Emerging Diseases》2020,67(2):1035-1041
As an emerging disease, the porcine epidemic diarrhoea virus has caused substantial economic losses to the pork industry in Mexico, leading to piglet mortality rates of up to 100%. For detection, sequencing and genetic characterization of the virus, 68 samples of one‐week‐old piglets from pork farms in 17 states of Mexico were analysed. In total, 53 samples were positive by real‐time RT‐PCR, confirming the presence of the virus in 15 states. Twenty‐eight samples from 10 states were amplified by endpoint RT‐PCR, and 20 sequences of the spike gene were obtained. A phylogenetic analysis based on the spike gene demonstrated that all Mexican strains are in Group II and are classified as non‐Indel‐S emerging variants. Three strains showed amino acid insertions: PEDv/MEX/GTO/LI‐DMZC15/2015 and PEDv/MEX/QRO/LI‐DMZC45/2016 showed one amino acid insertion (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/LI‐DMZC49/2019 showed one and two amino acid insertions (422C423 and 537SQ538), with the second insertion in the COE region. These results provide evidence of the prevalence of emerging, non‐Indel‐S strains of the virus are currently circulating in Mexico during 2016–2018, when three of which have amino acid insertions: PEDv/MEX/GTO/IN‐DMZC15/2015 and PEDv/MEX/QRO/IN‐DMZC45/2016 have one amino acid insertion each (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/IN‐DMZC49/2019 has one (422C423) and two amino acid insertions (537SQ538), the latter being in the COE region, which could generate new antigenic variants. 相似文献
54.
Sofia Henriques Ferreira Maria Morais Daniela Nunes Maria Joo Oliveira Ana Rovisco Ana Pimentel Hugo guas Elvira Fortunato Rodrigo Martins 《Materials》2021,14(9)
The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min−1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight. 相似文献
55.
Elvira Bisbe Albert Garcia-Casanovas Carles Illa Jordi Varela Misericordia Basora Marta Barquero Maria J. Colomina Lucia Gonzlez Axel Hofmann MAPBM Working Group 《Trasfusione del sangue》2021,19(3):205
BackgroundPatient blood management (PBM) is an evidence-based care bundle with proven ability to improve patients’ outcomes by managing and preserving the patient’s own blood. Since 2010, the World Health Organisation has urged member states to implement PBM. However, there has been limited progress in developing PBM programmes in hospitals due to the implicit challenges of implementing them. To address these challenges, we developed a Maturity Assessment Model (MAPBM) to assist healthcare organisations to measure, benchmark, assess in PBM, and communicate the results of their PBM programmes. We describe the MAPBM model, its benchmarking programme, and the feasibility of implementing it nationwide in Spain.Materials and methodsThe MAPBM considers the three dimensions of a transformation effort (structure, process and outcomes) and grades these within a maturity scale matrix. Each dimension includes the various drivers of a PBM programme, and their corresponding measures and key performance indicators. The structure measures are qualitative, and obtained using a survey and structured self-assessment checklist. The key performance indicators for process and outcomes are quantitative, and based on clinical data from the hospitals’ electronic medical records. Key performance indicators for process address major clinical recommendations in each PBM pillar, and are applied to six common procedures characterised by significant blood loss.ResultsIn its first 5 years, the MAPBM was deployed in 59 hospitals and used to analyse 181,826 hospital episodes, which proves the feasibility of implementing a sustainable model to measure and compare PBM clinical practice and outcomes across hospitals in Spain.ConclusionThe MAPBM initiative aims to become a useful tool for healthcare organisations to implement PBM programmes and improve patients’ safety and outcomes. 相似文献
56.
Identification of the hemangioblast in postnatal life 总被引:28,自引:11,他引:28
Pelosi E Valtieri M Coppola S Botta R Gabbianelli M Lulli V Marziali G Masella B Müller R Sgadari C Testa U Bonanno G Peschle C 《Blood》2002,100(9):3203-3208
57.
In vivo CAMPATH-1H prevents graft-versus-host disease following nonmyeloablative stem cell transplantation 总被引:9,自引:22,他引:9
Kottaridis PD Milligan DW Chopra R Chakraverty RK Chakrabarti S Robinson S Peggs K Verfuerth S Pettengell R Marsh JC Schey S Mahendra P Morgan GJ Hale G Waldmann H de Elvira MC Williams CD Devereux S Linch DC Goldstone AH Mackinnon S 《Blood》2000,96(7):2419-2425
A novel nonmyeloablative conditioning regimen was investigated in 44 patients with hematologic malignancies. The median patient age was 41 years. Many of the patients had high-risk features, including 19 patients with a previous failed transplant. Recipient conditioning consisted of CAMPATH-1H, 20 mg/day on days -8 to -4; fludarabine, 30 mg/m(2) on days -7 to -3; and melphalan, 140 mg/m(2) on day -2. Thirty-six recipients received unmanipulated granculocyte colony-stimulating factor-mobilized peripheral blood stem cells from HLA-identical siblings, and 8 received unmanipulated marrow from matched unrelated donors. GVHD prophylaxis was with cyclosporine A alone for 38 patients and cyclosporine A plus methotrexate for 6 sibling recipients. Forty-two of the 43 evaluable patients had sustained engraftment. Results of chimerism analysis using microsatellite polymerase chain reaction indicate that 18 of 31 patients studied were full-donor chimeras while the other patients were mixed chimeras in one or more lineages. At a median follow-up of 9 months (range 3 to 29 months), 33 patients remain alive in complete remission or with no evidence of disease progression. Seven patients relapsed or progressed post-transplantation, and 4 of them subsequently died. Four patients died of regimen-related complications. There were no cases of grades III-IV acute GVHD. Only 2 patients developed grade II acute GVHD, and only 1 had chronic GVHD. The estimated probability of nonrelapse mortality was 11%. Although longer follow-up is needed to establish the long-term remission rates, this study demonstrates that this nonmyeloablative preparative regimen is associated with durable engraftment, minimal toxicity, and low incidence of GVHD. 相似文献
58.
Elvira Isganaitis Melissa Woo Huijuan Ma Michael Chen Wen Kong Aristides Lytras Vicencia Sales Jennifer DeCoste-Lopez Kyung-Ju Lee Cianna Leatherwood Deborah Lee Connor Fitzpatrick Walter Gall Steven Watkins Mary-Elizabeth Patti 《Diabetes》2014,63(2):688-700
Maternal obesity and gestational diabetes mellitus (GDM) are associated with obesity and diabetes risk in offspring. We tested whether maternal insulin resistance, which frequently coexists with GDM and obesity, could independently contribute to dysregulation of offspring metabolism. Female mice haploinsufficient for insulin receptor substrate-1 (IRS1-het) are hyperinsulinemic and insulin resistant during pregnancy, despite normal plasma glucose and body weight, and thus serve as a model of isolated maternal insulin resistance. Wild-type (WT) offspring of IRS1-het dams insulin resistance-exposed [IR-exposed] were compared with WT offspring of WT dams. Despite no differences in adiposity, male IR-exposed pups were glucose intolerant (P = 0.04) and hyperinsulinemic (1.3-fold increase, P = 0.02) by 1 month of age and developed progressive fasting hyperglycemia. Moreover, male IR-exposed pups challenged with high-fat diet exhibited insulin resistance. Liver lipidomic analysis of 3-week-old IR-exposed males revealed increases in the 16:1n7 fraction of several lipid classes, suggesting increased Scd1 activity. By 6 months of age, IR-exposed males had increased lipid accumulation in liver as well as increased plasma refed fatty acids, consistent with disrupted lipid metabolism. Our results indicate that isolated maternal insulin resistance, even in the absence of hyperglycemia or obesity, can promote metabolic perturbations in male offspring. 相似文献
59.
Mariasanta Napolitano Alberto Dolce Giuseppe Celenza Elvira Grandone Maria Grazia Perilli Sergio Siragusa Gaspare Carta Assunta Orecchioni Guglielmo Mariani 《Annals of hematology》2014,93(4):557-563
In women of fertile age, iron loss consequent to excessive menstrual discharge is by far the most frequent cause of iron-deficient anemia. However, the relationship between menstrual discharge and iron loss is poorly understood. In this prospective study, total menstrual and iron losses were assayed in a large cohort of non-anemic women and women with excessive menstrual blood losses (menorrhagia) in order to provide data useful for intervention. One hundred and five Caucasian women aged 20–45 years were recruited. Blood cell count and serum ferritin (SF) levels were determined in each case before menses. Menstrual fluid losses (MFL) were determined using a standardized pads’ weight method. Hematin concentration was assayed by a variant of the Alkaline Hematin Method from which iron concentration was calculated. Mean SF levels were 36.2 (range 8.6–100) ng/ml in healthy women and 6.4 (range 5–14) ng/ml in patients with menorrhagia. Median values of iron lost/cycle were 0.87 mg in healthy women and 5.2 mg in patients with menorrhagia (ranges 0.102–2.569 and 1.634–8.665 mg, respectively, p?<?0.001). In women with menorrhagia, iron lost/cycle strongly correlated (0.789, p?<?0.001) with MFL. In conclusion, healthy women with normal menses lose, on average, 1 mg iron/cycle. Average iron losses in patients with menorrhagia are, at least in our cohort, on average, five-to-six times higher than normal. Most women with menorrhagia had totally depleted iron stores. Indirect, quantitative evaluation of iron lost with menses may be useful to assess the risk of developing iron-deficient anemia in individual patients. 相似文献
60.
Petya Valcheva Anna Cardus Sara Panizo Eva Parisi Milica Bozic Jose M. Lopez Novoa Adriana Dusso Elvira Fernández Jose M. Valdivielso 《Atherosclerosis》2014