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1.
Clin Radiol ; 77(1): 6-18, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34154835

RESUMEN

Most of the complications following lung cancer surgery occur in the early postoperative period and can result in significant morbidity and mortality. Delayed complications can also occur. Diagnosing these complications can be challenging because clinical manifestations are non-specific. Imaging plays an important role in detecting these complications in a timely manner and facilitates prompt interventions. Hence, it is important to have knowledge of the expected anatomical alterations following lung cancer surgeries, and the spectrum of post-surgical complications and their respective imaging findings to avoid misinterpretations or delay in diagnosis.


Asunto(s)
Diagnóstico por Imagen/métodos , Neoplasias Pulmonares/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Humanos , Pulmón/diagnóstico por imagen , Periodo Posoperatorio , Tórax/diagnóstico por imagen
2.
J Helminthol ; 94: e84, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31500673

RESUMEN

In many tropical areas schistosomiasis is a major health problem causing hepatosplenic, intestinal or urogenital complaints. Hepatosplenic schistosomiasis mansoni is also characterized by blood coagulation abnormalities. Liver pathology plays a role in the development of haemostatic changes and the parasitic infection may directly affect coagulation. However, these contributing factors cannot be studied separately in hepatosplenic schistosomiasis infections. This pilot study provides insight in haemostatic changes in urinary schistosomiasis by studying coagulation parameters in schistosomiasis haematobium-infected Gabonese schoolchildren. Selection on urinary schistosomiasis patients without hepatosplenic complaints allows for the investigation of the direct effects of the parasite on haemostasis. Levels of von Willebrand Factor (VWF) antigen, active VWF and osteoprotegerin were elevated, indicating inflammation-mediated endothelial activation. In contrast to hepatosplenic schistosomiasis, thrombin-antithrombin complex and D-dimer levels were not affected. Despite its small sample size, this study clearly indicates that Schistosoma haematobium directly alters the activation status of the endothelium, without initiation of coagulation.


Asunto(s)
Coagulación Sanguínea , Hemostáticos/análisis , Esquistosomiasis Urinaria/orina , Instituciones Académicas/estadística & datos numéricos , Infecciones Urinarias/parasitología , Adolescente , Animales , Estudios de Casos y Controles , Niño , Femenino , Gabón , Hemostasis , Humanos , Masculino , Proyectos Piloto , Schistosoma haematobium/patogenicidad , Esquistosomiasis Urinaria/sangre
3.
Int J Obes (Lond) ; 41(8): 1288-1294, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28465607

RESUMEN

BACKGROUND/OBJECTIVES: Insulin resistance of adipose tissue is an important feature of obesity-related metabolic disease. However, assessment of lipolysis in humans requires labor-intensive and expensive methods, and there is limited validation of simplified measurement methods. We aimed to validate simplified methods for the quantification of adipose tissue insulin resistance against the assessment of insulin sensitivity of lipolysis suppression during hyperinsulinemic-euglycemic clamp studies. SUBJECTS/METHODS: We assessed the insulin-mediated suppression of lipolysis by tracer-dilution of [1,1,2,3,3-2H5]glycerol during hyperinsulinemic-euglycemic clamp studies in 125 overweight or obese adults (85 men, 40 women; age 50±11 years; body mass index 38±7 kg m-2). Seven indices of adipose tissue insulin resistance were validated against the reference measurement method. RESULTS: Low-dose insulin infusion resulted in suppression of the glycerol rate of appearance ranging from 4% (most resistant) to 85% (most sensitive), indicating a good range of adipose tissue insulin sensitivity in the study population. The reference method correlated with (1) insulin-mediated suppression of plasma glycerol concentrations (r=0.960, P<0.001), (2) suppression of plasma non-esterified fatty acid (NEFA) concentrations (r=0.899, P<0.001), (3) the Adipose tissue Insulin Resistance (Adipo-IR) index (fasting plasma insulin-NEFA product; r=-0.526, P<0.001), (4) the fasting plasma insulin-glycerol product (r=-0.467, P<0.001), (5) the Adipose Tissue Insulin Resistance Index (fasting plasma insulin-basal lipolysis product; r=0.460, P<0.001), (6) the Quantitative Insulin Sensitivity Check Index (QUICKI)-NEFA index (r=0.621, P<0.001), and (7) the QUICKI-glycerol index (r=0.671, P<0.001). Bland-Altman plots showed no systematic errors for the suppression indices but proportional errors for all fasting indices. Receiver-operator characteristic curves confirmed that all indices were able to detect adipose tissue insulin resistance (area under the curve ⩾0.801, P<0.001). CONCLUSIONS: Adipose tissue insulin sensitivity (that is, the antilipolytic action of insulin) can be reliably quantified in overweight and obese humans by simplified index methods. The sensitivity and specificity of the Adipo-IR index and the fasting plasma insulin-glycerol product, combined with their simplicity and acceptable agreement, suggest that these may be most useful in clinical practice.


Asunto(s)
Tejido Adiposo/metabolismo , Resistencia a la Insulina , Síndrome Metabólico/metabolismo , Obesidad/metabolismo , Sobrepeso/metabolismo , Tejido Adiposo/efectos de los fármacos , Adulto , Índice de Masa Corporal , Femenino , Técnica de Clampeo de la Glucosa , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Lipólisis/efectos de los fármacos , Masculino , Síndrome Metabólico/tratamiento farmacológico , Síndrome Metabólico/fisiopatología , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/fisiopatología , Sobrepeso/complicaciones , Sobrepeso/fisiopatología , Valores de Referencia
4.
Ann Rheum Dis ; 74(6): 1011-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24464962

RESUMEN

OBJECTIVES: To assess the prevalence of the main causes of morbi-mortality in the antiphospholipid syndrome (APS) during a 10-year-follow-up period and to compare the frequency of early manifestations with those that appeared later. METHODS: In 1999, we started an observational study of 1000 APS patients from 13 European countries. All had medical histories documented when entered into the study and were followed prospectively during the ensuing 10 years. RESULTS: 53.1% of the patients had primary APS, 36.2% had APS associated with systemic lupus erythematosus and 10.7% APS associated with other diseases. Thrombotic events appeared in 166 (16.6%) patients during the first 5-year period and in 115 (14.4%) during the second 5-year period. The most common events were strokes, transient ischaemic attacks, deep vein thromboses and pulmonary embolism. 127 (15.5%) women became pregnant (188 pregnancies) and 72.9% of pregnancies succeeded in having one or more live births. The most common obstetric complication was early pregnancy loss (16.5% of the pregnancies). Intrauterine growth restriction (26.3% of the total live births) and prematurity (48.2%) were the most frequent fetal morbidities. 93 (9.3%) patients died and the most frequent causes of death were severe thrombosis (36.5%) and infections (26.9%). Nine (0.9%) cases of catastrophic APS occurred and 5 (55.6%) of them died. The survival probability at 10 years was 90.7%. CONCLUSIONS: Patients with APS still develop significant morbidity and mortality despite current treatment. It is imperative to increase the efforts in determining optimal prognostic markers and therapeutic measures to prevent these complications.


Asunto(s)
Síndrome Antifosfolípido/mortalidad , Lupus Eritematoso Sistémico/mortalidad , Trombosis/mortalidad , Aborto Espontáneo/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/epidemiología , Niño , Preescolar , Estudios de Cohortes , Epilepsia/etiología , Femenino , Retardo del Crecimiento Fetal/epidemiología , Humanos , Lactante , Recién Nacido , Infecciones/etiología , Infecciones/mortalidad , Ataque Isquémico Transitorio/etiología , Livedo Reticularis/etiología , Estudios Longitudinales , Lupus Eritematoso Sistémico/complicaciones , Masculino , Persona de Mediana Edad , Embarazo , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Estudios Prospectivos , Embolia Pulmonar/etiología , Embolia Pulmonar/mortalidad , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Trombocitopenia/etiología , Trombosis/etiología , Trombosis de la Vena/etiología , Trombosis de la Vena/mortalidad , Adulto Joven
5.
Eur J Clin Microbiol Infect Dis ; 34(5): 1039-44, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25680316

RESUMEN

Ulcerative colitis (UC) is thought to originate from a disbalance in the interplay between the gut microbiota and the innate and adaptive immune system. Apart from the bacterial microbiota, there might be other organisms, such as parasites or viruses, that could play a role in the aetiology of UC. The primary objective of this study was to compare the prevalence of Blastocystis sp. in a cohort of patients with active UC and compare that to the prevalence in healthy controls. We studied patients with active UC confirmed by endoscopy included in a randomised prospective trial on the faecal transplantation for UC. A cohort of healthy subjects who served as donors in randomised trials on faecal transplantation were controls. Healthy subjects did not have gastrointestinal symptoms and were extensively screened for infectious diseases by a screenings questionnaire, extensive serologic assessment for viruses and stool analysis. Potential parasitic infections such as Blastocystis were diagnosed with the triple faeces test (TFT). The prevalence of Blastocystis sp. were compared between groups by Chi-square testing. A total of 168 subjects were included, of whom 45 had active UC [median age 39.0 years, interquartile range (IQR) 32.5-49.0, 49 % male] and 123 were healthy subjects (median age 27 years, IQR 22.0-37.0, 54 % male). Blastocystis sp. was present in the faeces of 40/123 (32.5 %) healthy subjects and 6/45 (13.3 %) UC patients (p = 0.014). Infection with Blastocystis is significantly less frequent in UC patients as compared to healthy controls.


Asunto(s)
Infecciones por Blastocystis/complicaciones , Infecciones por Blastocystis/epidemiología , Blastocystis/aislamiento & purificación , Colitis Ulcerosa/etiología , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Prevalencia , Ensayos Clínicos Controlados Aleatorios como Asunto , Adulto Joven
6.
J Econ Entomol ; 108(4): 1837-51, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26470326

RESUMEN

In 2007-2008, we examined the flight responses of wood-boring beetles (Coleoptera: Cerambycidae and Buprestidae) to multiple-funnel traps baited with the pine volatiles, ethanol, and α-pinene [85% (-)], and the bark beetle pheromones, racemic ipsenol and racemic ipsdienol. Experiments were conducted in mature pine stands in Canada (Ontario and New Brunswick) and the United States (Arkansas, Florida, Michigan, New Hampshire, North Carolina, Ohio, Tennessee, and Wisconsin). At each location, traps were deployed in 10 replicate blocks of four traps per block. The trap treatments were: 1) blank control; 2) ipsenol and ipsdienol; 3) ethanol and α-pinene; and 4) a quaternary blend of ipsenol, ipsdienol, ethanol, and α-pinene. Traps baited with the quaternary blend caught the greatest numbers of Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Acmaeops proteus (Kirby), Astylopsis sexguttata (Say), Rhagium inquisitor (L.) (Cerambycidae), and Buprestis lineata (F.) (Buprestidae). Traps baited with ethanol and α-pinene caught the greatest numbers of Arhopalus rusticus (LeConte), Asemum striatum (L.), Tetropium spp., Xylotrechus sagittatus (Germar) (Cerambycidae), and Buprestis maculipennis Gory (Buprestidae) with minimal interruption by ipsenol and ipsdienol. Our results suggest that multiple-funnel traps baited with the quaternary lure blend of ipsenol, ipsdienol, ethanol, and α-pinene are effective for trapping various species of wood-boring beetles in pine forests of eastern North America, and may have utility in detection programs for adventive species in North America and overseas.


Asunto(s)
Escarabajos/efectos de los fármacos , Bosques , Control Biológico de Vectores , Feromonas/farmacología , Monoterpenos Acíclicos , Alcoholes/farmacología , Animales , Monoterpenos Bicíclicos , Canadá , Etanol/farmacología , Monoterpenos/farmacología , Octanoles/farmacología , Pinus/crecimiento & desarrollo , Especificidad de la Especie , Estados Unidos
7.
Opt Express ; 22(25): 30473-81, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25606993

RESUMEN

We report on a metamolecule antenna, based on a fish-scale design but augmented with two split-ring resonators (SRRs) placed within the fish-scale loops. The properties of the antenna resonator, with and without additional SRRs, were examined using finite element method simulations (COMSOL Multiphysics). The simulation findings were subsequently confirmed experimentally, using a vector network analyser coupled to an antenna-loaded coplanar waveguide (CPW). The addition of SRRs to the fish-scale meta-molecule leads to a demonstrably large increase in microwave-absorption. It is shown that the fish-scale/SRR/CPW combination performs as a microwave antenna. Simulations of the antenna gain and far-field emission are presented and discussed.

8.
Phys Rev Lett ; 113(6): 067601, 2014 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-25148349

RESUMEN

The magnetization dynamics of a wound [DyFe(2)(20 Å)/YFe(2)(80 Å)](×40) exchange spring multilayer have been explored in optical pump probe experiments. Ultrafast optical heating was used to modify the magnetic parameters of the multilayer, while the time resolved magneto-optical Kerr effect was used to probe its response. Although the probe signal is dominated by precession and winding of the exchange spring within the soft YFe(2) layer, reorientation of the DyFe(2) hard-layer magnetization is detected on time scales less than 100 ps. Micromagnetic simulations reproduce the main features of the experimental data and indicate a dramatic optically induced reduction of the hard-layer anisotropy. The results establish the feasibility of switching a spring system by means of parametric excitation.

9.
Haemophilia ; 20(1): 92-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24028772

RESUMEN

The effects of coagulation factor concentrate infusion on restoring secondary haemostasis in patients with haemophilia are obvious. It is not known whether coagulation factor concentrate infusion affects primary haemostasis or induces an acute inflammatory response. In this study, the influence of a factor VIII (FVIII) concentrate bolus infusion on platelet activation and responsiveness, endothelial activation, and inflammation in adult patients with severe haemophilia A was assessed. VWF showed a mild, but significant decrease 15 min after FVIII infusion (85.02 IU dL(-1)) vs. before infusion (92.04 IU dL(-1) ; P = 0.017), while ADAMTS-13 levels also show a mild but significant decrease from 66.1 ng mL(-1) before infusion, to 53.9 ng mL(-1) (P = 0.012) 15 min after and 50.8 ng mL(-1) (P = 0.050) 60 min after infusion. Platelet P-selectin expression decreased 15 min (33.3 AU) and 60 min (38.7 AU) after infusion compared to before infusion (41.3 AU; P = 0.018 and 0.036). In conclusion, a single infusion of a high dose FVIII concentrate in haemophilia A patients may influence primary haemostasis by decreasing VWF, ADAMTS-13 and the number of circulating activated platelets. These effects possibly occur as a consequence of binding of the infused FVIII to VWF, influencing its processing. When treating severe haemophilia A patients with coagulation concentrate infusion, one should realize this does not merely correct FVIII levels but also may influence primary haemostasis.


Asunto(s)
Proteínas ADAM/metabolismo , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Hemofilia A/metabolismo , Factor de von Willebrand/metabolismo , Proteínas ADAM/sangre , Proteína ADAMTS13 , Adulto , Plaquetas/metabolismo , Citocinas/biosíntesis , Citocinas/sangre , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Factor VIII/administración & dosificación , Hemofilia A/sangre , Humanos , Inflamación/metabolismo , Mediadores de Inflamación/sangre , Mediadores de Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Phys Rev Lett ; 111(9): 090506, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-24033014

RESUMEN

We realize indirect partial measurement of a transmon qubit in circuit quantum electrodynamics by interaction with an ancilla qubit and projective ancilla measurement with a dedicated readout resonator. Accurate control of the interaction and ancilla measurement basis allows tailoring the measurement strength and operator. The tradeoff between measurement strength and qubit backaction is characterized through the distortion of a qubit Rabi oscillation imposed by ancilla measurement in different bases. Combining partial and projective qubit measurements, we provide the solid-state demonstration of the correspondence between a nonclassical weak value and the violation of a Leggett-Garg inequality.

11.
Nature ; 447(7146): 836-9, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17568742

RESUMEN

Quantum computation requires quantum logic gates that use the interaction within pairs of quantum bits (qubits) to perform conditional operations. Superconducting qubits may offer an attractive route towards scalable quantum computing. In previous experiments on coupled superconducting qubits, conditional gate behaviour and entanglement were demonstrated. Here we demonstrate selective execution of the complete set of four different controlled-NOT (CNOT) quantum logic gates, by applying microwave pulses of appropriate frequency to a single pair of coupled flux qubits. All two-qubit computational basis states and their superpositions are used as input, while two independent single-shot SQUID detectors measure the output state, including qubit-qubit correlations. We determined the gate's truth table by directly measuring the state transfer amplitudes and by acquiring the relevant quantum phase shift using a Ramsey-like interference experiment. The four conditional gates result from the symmetry of the qubits in the pair: either qubit can assume the role of control or target, and the gate action can be conditioned on either the 0-state or the 1-state. These gates are now sufficiently characterized to be used in quantum algorithms, and together form an efficient set of versatile building blocks.

12.
Environ Pollut ; 316(Pt 2): 120663, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36395907

RESUMEN

Since the industrial era, chemicals have been ubiquitous in worldwide ecosystems. Despite the discontinued release of highly toxic persistent organic pollutants (POPs) in the environment, the levels of some POPs are still being measured in the Canadian Arctic. These contaminants are of great concern due to their persistence, toxicity, and levels of bioaccumulation in food chains. Animals occupying top trophic positions in the Canadian Arctic, particularly polar bears, are exposed to these contaminants mainly through their diet. Our study investigated the levels of 30 metals (including total and methyl mercury) alkaline and alkaline earth metals, 15 polycyclic aromatic compounds and their alkyl congeners (PACs), 6 chlordanes (CHLs), and 20 polychlorinated biphenyls (PCBs), in 49 polar bears from the Canadian Arctic. Contaminant burden was measured in liver, muscle, and fat in bears of different sex, age, and locations. A principal component analysis did not distinguish differences between age and sex profiles for most contaminants. However, the concentrations measured and their distribution in the tissues confirm findings observed in past studies. This study highlights the importance of continual monitoring of polar bear health (e.g., newly detected PACs were measured within this study) and evaluating those impacts for the next generations of polar bears.


Asunto(s)
Compuestos Policíclicos , Ursidae , Animales , Ecosistema , Canadá , Músculos , Hígado
13.
Mol Ecol ; 21(23): 5728-44, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23106425

RESUMEN

Understanding the evolutionary histories of invasive species is critical to adopt appropriate management strategies, but this process can be exceedingly complex to unravel. As illustrated in this study of the worldwide invasion of the woodwasp Sirex noctilio, population genetic analyses using coalescent-based scenario testing together with Bayesian clustering and historical records provide opportunities to address this problem. The pest spread from its native Eurasian range to the Southern Hemisphere in the 1900s and recently to Northern America, where it poses economic and potentially ecological threats to planted and native Pinus spp. To investigate the origins and pathways of invasion, samples from five continents were analysed using microsatellite and sequence data. The results of clustering analysis and scenario testing suggest that the invasion history is much more complex than previously believed, with most of the populations being admixtures resulting from independent introductions from Europe and subsequent spread among the invaded areas. Clustering analyses revealed two major source gene pools, one of which the scenario testing suggests is an as yet unsampled source. Results also shed light on the microevolutionary processes occurring during introductions, and showed that only few specimens gave rise to some of the populations. Analyses of microsatellites using clustering and scenario testing considered against historical data drastically altered our understanding of the invasion history of S. noctilio and will have important implications for the strategies employed to fight its spread. This study illustrates the value of combining clustering and ABC methods in a comprehensive framework to dissect the complex patterns of spread of global invaders.


Asunto(s)
Genética de Población , Himenópteros/genética , Especies Introducidas , Modelos Genéticos , África , Animales , Teorema de Bayes , Análisis por Conglomerados , ADN Mitocondrial , Complejo IV de Transporte de Electrones/genética , Europa (Continente) , Femenino , Pool de Genes , Variación Genética , Haplotipos/genética , Masculino , Repeticiones de Microsatélite , Datos de Secuencia Molecular , América del Norte , América del Sur
14.
Phys Rev Lett ; 109(24): 243904, 2012 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-23368321

RESUMEN

We show that subterahertz transmission of the superconducting metamaterial, an interlinked two-dimensional network of subwavelength resonators connected by a continuous superconducting wire loop, can be dynamically modulated by passing electrical current through it. We have identified the main mechanisms of modulation that correspond to the suppression of the superconductivity in the network by magnetic field and heat dissipation. Using the metamaterial fabricated from thin niobium film, we were able to demonstrate a transmission modulation depth of up to 45% and a bandwidth of at least 100 kHz. The demonstrated approach may be implemented with other superconducting materials at frequencies below the superconducting gap in the THz and subterahertz bands.

15.
Lupus ; 21(7): 704-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22635207

RESUMEN

The antiphospholipid syndrome (APS) is diagnosed when patients with thrombotic complications or foetal losses have elevated levels of antiphospholipid antibodies in their plasmas. The term APS is confusing, because the pathogenic auto-antibodies are not directed against phospholipids but towards a plasma protein, ß(2)-glycoprotein I. For many years the reason why auto-antibodies against ß(2)-glycoprotein I were pro-thrombotic was unclear, because man and mice deficient in ß(2)-glycoprotein I do not express a clear phenotype. Animal models in which passive transfer of patient antibodies into mice resulted in an increased thrombotic response have provided novel insights in the importance of this protein in the pathology of APS.


Asunto(s)
Síndrome Antifosfolípido/fisiopatología , Trombosis/inmunología , Animales , Humanos , Trombosis/fisiopatología , beta 2 Glicoproteína I/inmunología
16.
Eur J Vasc Endovasc Surg ; 43(6): 675-80, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22436262

RESUMEN

OBJECTIVES: Customized aortic repair (CAR) is a new concept for endovascular aortic aneurysm repair in which a non-polymerised elastomer is injected to fill the aneurysm sac around a balloon catheter. Amongst other variables, the thrombogenicity of the elastomer should be tested, before further clinical experiments can take place. The aim of this human ex vivo study was to measure the thrombogenicity of the elastomer and to compare it to expanded polytetrafluoroethylene (ePTFE). DESIGN AND MATERIALS: In a validated ex vivo model, non-anticoagulated blood was drawn from the antecubital veins of 10 healthy donors with a 19-gauge needle. It was drawn through elastomer tubes and through ePTFE Gore-Tex vascular grafts, both 60 cm long and with an inner diameter of 3 mm. METHODS: Fibrinopeptide A (FPA) and P-selectin expression was measured in blood samples, collected at the end of the grafts. After the experiments, the deposition of platelets and fibrin onto the grafts was visualised by scanning electron microscopy. RESULTS: For these graft types, a progressive increase in FPA production was observed in time. No significant difference was observed between the elastomer and ePTFE grafts (p > 0.05). No increase in P-selectin expression, and thereby no platelet activation, was observed in the perfusate of either grafts (p > 0.05). By scanning electron microscopy, numerous platelet aggregates were observed on the ePTFE grafts, whereas just a few adhered platelets and no aggregates were observed in the elastomer grafts. CONCLUSIONS: The elastomer in its current formulation has a low thrombogenicity, comparable to ePTFE, making it an ideal substance for endovascular aneurysm sac filling. Further research should clarify the feasibility of CAR in vivo.


Asunto(s)
Aneurisma de la Aorta/terapia , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Dimetilpolisiloxanos/administración & dosificación , Procedimientos Endovasculares/instrumentación , Politetrafluoroetileno , Elastómeros de Silicona/administración & dosificación , Trombosis/prevención & control , Adulto , Aneurisma de la Aorta/sangre , Aneurisma de la Aorta/cirugía , Implantación de Prótesis Vascular/efectos adversos , Dimetilpolisiloxanos/efectos adversos , Procedimientos Endovasculares/efectos adversos , Fibrina/metabolismo , Fibrinopéptido A/metabolismo , Humanos , Inyecciones , Masculino , Microscopía Electrónica de Rastreo , Selectina-P/sangre , Adhesividad Plaquetaria , Diseño de Prótesis , Elastómeros de Silicona/efectos adversos , Trombosis/sangre , Trombosis/etiología , Trombosis/patología , Factores de Tiempo , Adulto Joven
17.
J Intern Med ; 270(2): 110-22, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21323768

RESUMEN

The antiphospholipid syndrome (APS) identifies a condition at increased risk of vascular occlusion and/or pregnancy complications. Patients are defined as having APS if they have at least one clinical (vascular occlusion and/or pregnancy complications) and one laboratory criterion at the same time. The laboratory criteria that define APS are repeated positivity (confirmed 12 weeks apart) for lupus anticoagulants and/or antibodies targeted against cardiolipin or ß(2) -glycoprotein I immobilized on solid surfaces. Over the years, APS has attracted the interest of many medical specialties. The aim of this review is to provide an update on (i) the laboratory criteria that determine the presence of APS, (ii) how the antibodies increase the risk of vascular occlusion and foetal loss and (iii) the treatment of the related clinical events.


Asunto(s)
Anticoagulantes/uso terapéutico , Síndrome Antifosfolípido/diagnóstico , Síndrome Antifosfolípido/tratamiento farmacológico , Síndrome Antifosfolípido/inmunología , Biomarcadores/sangre , Femenino , Humanos , Inhibidor de Coagulación del Lupus/análisis , Embarazo , Complicaciones Cardiovasculares del Embarazo/diagnóstico , beta 2 Glicoproteína I/inmunología
18.
Lupus ; 20(2): 182-90, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21303835

RESUMEN

Current classification criteria for definite antiphospholipid syndrome (APS) mandate the use of one or more of three positive 'standardized' laboratory assays to detect antiphospholipid antibodies (aPL) (viz: anticardiolipin [aCL] IgG and IgM; anti-ß(2)glycoprotein I [anti-ß(2)GPI] antibodies IgG and IgM; and/or a lupus anticoagulant [LAC]), when at least one of the two major clinical manifestations (thrombosis or pregnancy losses) are present. Although, efforts of standardization for these 'criteria' aPL tests have been conducted over the last 27 years, reports of inconsistencies, inter-assay and inter-laboratory variation in the results of aCL, LAC, and anti-ß(2)GPI, and problems with the interpretation and the clinical value of the tests still exist, which affect the consistency of the diagnosis of APS. A Task Force of scientists and pioneers in the field from different countries, subdivided in three working groups, discussed and analyzed critical questions related to 'criteria' aPL tests in an evidence-based manner, during the 13(th) International Congress on Antiphospholipid Antibodies (APLA 2010, April 13-16, 2010, Galveston, TX). These included: review of the standardization and the need for international consensus protocol for aCL and anti-ß(2)GPI tests; the use of monoclonal and/or polyclonal standards in the calibration curve of those tests; and the need for establishment of international units of measurement for anti-ß(2)GPI tests. The group also reviewed the recently updated guidelines for LAC testing, and analyzed and discussed the possibility of stratification of 'criteria' aPL tests as risk factors for APS, as well as the clinical value of single positive vs. multiple aPL positivity. The group members presented, discussed, analyzed data, updated and re-defined those critical questions at a preconference workshop that was open to congress attendees. This report summarizes the findings, conclusions, and recommendations of this Task Force.


Asunto(s)
Comités Consultivos , Anticuerpos Antifosfolípidos/análisis , Síndrome Antifosfolípido/diagnóstico , Congresos como Asunto , Anticuerpos Antifosfolípidos/inmunología , Síndrome Antifosfolípido/clasificación , Síndrome Antifosfolípido/inmunología , Pruebas Diagnósticas de Rutina/métodos , Pruebas Diagnósticas de Rutina/normas , Femenino , Guías como Asunto , Humanos , Embarazo , Encuestas y Cuestionarios , Texas
19.
Nat Med ; 5(1): 107-11, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9883848

RESUMEN

Severe thrombocytopenia frequently occurs in patients receiving chemotherapy and in patients with autoimmune disorders. Thrombocytopenia is associated with bleeding, which may be serious and life threatening. Current treatment strategies for thrombocytopenia may require transfusion of allogeneic platelets, which is associated with serious drawbacks. These include the occurrence of anti-platelet antibodies, which may result in refractoriness to further platelet transfusions, and the potential risk of transfer of blood-borne diseases. Therefore, we have recently developed a platelet substitute product (Synthocytes), which is composed of human albumin microcapsules with fibrinogen immobilized on their surface. Here we show that the intravenous administration of these microcapsules not only corrects the prolonged bleeding time in rabbits rendered thrombocytopenic either by anti-platelet antibodies or by chemotherapy, but also reduces bleeding from surgical wounds inflicted in the abdominal skin and musculature. No potential systemic prothrombotic effect of the microcapsules was observed in a model of rabbit venous thrombosis. As for the mechanism of action, experiments with normal and thrombocytopenic human blood in an endothelial cell matrix-coated perfusion chamber demonstrated an interaction between the fibrinogen-coated albumin microcapsules and native platelets. It was shown that the fibrinogen-coated albumin microcapsules could facilitate platelet adhesion to endothelial cell matrix and correct the impaired formation of platelet aggregates in relatively platelet-poor blood. This study indicates that fibrinogen-coated albumin microcapsules can act to improve primary hemostasis under thrombocytopenic conditions and may eventually be a promising agent for prophylaxis and treatment of bleeding in patients with severe thrombocytopenia.


Asunto(s)
Albúminas , Plaquetas , Sustitutos Sanguíneos , Fibrinógeno , Hemorragia/prevención & control , Trombocitopenia/terapia , Albúminas/efectos adversos , Animales , Cápsulas , Modelos Animales de Enfermedad , Fibrinógeno/efectos adversos , Humanos , Conejos , Trombosis , Factores de Tiempo
20.
Mycopathologia ; 172(6): 415-27, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21769633

RESUMEN

An important initial step in biofilm development and subsequent establishment of fungal infections by the human pathogen Candida glabrata is adherence to a surface. Adherence is mediated through a large number of differentially regulated cell wall-bound adhesins. The fungus can modify the incorporation of adhesins in the cell wall allowing crucial adaptations to new environments. In this study, expression and cell wall incorporation of C. glabrata adhesins were evaluated in biofilms cultured in two different media: YPD and a semi-defined medium SdmYg. Tandem mass spectrometry of isolated C. glabrata cell walls identified 22 proteins including six adhesins: the novel adhesins Awp5 and Awp6, Epa3 and the previously identified adhesins Epa6, Awp2 and Awp4. Regulation of expression of these and other relevant adhesin genes was investigated using real-time qPCR analysis. For most adhesin genes, significant up-regulation was observed in biofilms in at least one of the culturing media. However, this was not the case for EPA6 and AWP2, which is consistent with their gene products already being abundantly present in planktonic cultures grown in YPD medium. Furthermore, most of the adhesin genes tested also show medium-dependent differential regulation. These results underline the idea that many adhesins in C. glabrata are involved in biofilm formation and that their expression is tightly regulated and dependent on environmental conditions and growth phase. This may contribute to its potential to form resilient biofilms and cause infection in various host tissues.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Candida glabrata/fisiología , Adhesión Celular , Proteínas Fúngicas/biosíntesis , Regulación Fúngica de la Expresión Génica , Candida glabrata/crecimiento & desarrollo , Pared Celular/química , Pared Celular/metabolismo , Medios de Cultivo/química , Perfilación de la Expresión Génica , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría de Masas en Tándem
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