RESUMEN
Aging accounts for increased risk and dismal outcome of ischemic stroke. Here, we investigated the impact of age-related changes in the immune system on stroke. Upon experimental stroke, compared with young mice, aged mice had increased neutrophil clogging of the ischemic brain microcirculation, leading to worse no-reflow and outcomes. Aged mice showed an enhanced granulopoietic response to stroke that led to the accumulation of CD101+CD62Llo mature and CD177hiCD101loCD62Llo and CD177loCD101loCD62Lhi immature atypical neutrophils in the blood, endowed with increased oxidative stress, phagocytosis and procoagulant features. Production of CXCL3 by CD62Llo neutrophils of the aged had a key role in the development and pathogenicity of aging-associated neutrophils. Hematopoietic stem cell rejuvenation reverted aging-associated neutropoiesis and improved stroke outcome. In elderly patients with ischemic stroke, single-cell proteome profile of blood leukocytes identified CD62Llo neutrophil subsets associated with worse reperfusion and outcome. Our results unveil how stroke in aging leads to a dysregulated emergency granulopoiesis impacting neurological outcome.
Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Ratones , Animales , Neutrófilos , Leucocitos , Accidente Cerebrovascular/patología , Envejecimiento , Accidente Cerebrovascular Isquémico/patologíaRESUMEN
Whole-exome sequencing (WES) in families with an unexplained tendency for venous thromboembolism (VTE) may favor detection of low-frequency variants in genes with known contribution to hemostasis or associated with VTE-related phenotypes. WES analysis in six family members, three of whom affected by documented VTE, filtered for MAF < 0.04 in 192 candidate genes, revealed 22 heterozygous (16 missense and six synonymous) variants in patients. Functional prediction by multi-component bioinformatics tools, implemented by a database/literature search, including ClinVar annotation and QTL analysis, prioritized 12 missense variants, three of which (CRP Leu61Pro, F2 Asn514Lys and NQO1 Arg139Trp) were present in all patients, and the frequent functional variants FGB Arg478Lys and IL1A Ala114Ser. Combinations of prioritized variants in each patient were used to infer functional protein interactions. Different interaction patterns, supported by high-quality evidence, included eight proteins intertwined in the "acute phase" (CRP, F2, SERPINA1 and IL1A) and/or in the "fibrinogen complex" (CRP, F2, PLAT, THBS1, VWF and FGB) significantly enriched terms. In a wide group of candidate genes, this approach highlighted six low-frequency variants (CRP Leu61Pro, F2 Asn514Lys, SERPINA1 Arg63Cys, THBS1 Asp901Glu, VWF Arg1399His and PLAT Arg164Trp), five of which were top ranked for predicted deleteriousness, which in different combinations may contribute to disease susceptibility in members of this family.
Asunto(s)
Tromboembolia Venosa , Humanos , Tromboembolia Venosa/genética , Secuenciación del Exoma , Factor de von Willebrand/genética , Genes Reguladores , Biología ComputacionalRESUMEN
BACKGROUND: Thrombocytopenia is a serious issue for all patients with classical Wiskott-Aldrich syndrome (WAS) and X-linked thrombocytopenia (XLT) because it causes severe and life-threatening bleeding. Lentiviral gene therapy (GT) for WAS has shown promising results in terms of immune reconstitution. However, despite the reduced severity and frequency of bleeding events, platelet counts remain low in GT-treated patients. OBJECTIVE: We carefully investigated platelet defects in terms of phenotype and function in untreated patients with WAS and assessed the effect of GT treatment on platelet dysfunction. METHODS: We analyzed a cohort of 20 patients with WAS/XLT, 15 of them receiving GT. Platelet phenotype and function were analyzed by using electron microscopy, flow cytometry, and an aggregation assay. Platelet protein composition was assessed before and after GT by means of proteomic profile analysis. RESULTS: We show that platelets from untreated patients with WAS have reduced size, abnormal ultrastructure, and a hyperactivated phenotype at steady state, whereas activation and aggregation responses to agonists are decreased. GT restores platelet size and function early after treatment and reduces the hyperactivated phenotype proportionally to WAS protein expression and length of follow-up. CONCLUSIONS: Our study highlights the coexistence of morphologic and multiple functional defects in platelets lacking WAS protein and demonstrates that GT normalizes the platelet proteomic profile with consequent restoration of platelet ultrastructure and phenotype, which might explain the observed reduction of bleeding episodes after GT. These results are instrumental also from the perspective of a future clinical trial in patients with XLT only presenting with microthrombocytopenia.
Asunto(s)
Plaquetas/fisiología , Terapia Genética , Lentivirus/genética , Síndrome de Wiskott-Aldrich/sangre , Síndrome de Wiskott-Aldrich/terapia , Adolescente , Adulto , Plaquetas/ultraestructura , Niño , Preescolar , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Lactante , Masculino , Microscopía Electrónica de Transmisión , Fenotipo , Activación Plaquetaria , Recuento de Plaquetas , Proteína del Síndrome de Wiskott-Aldrich/metabolismoRESUMEN
INTRODUCTION: Inherited deficiencies in the coagulation pathway provide diversified models to investigate the molecular bases of perinatal lethality associated with null-like variants. Differently from X-linked haemophilias, homozygous/doubly heterozygous null variants in the rare autosomally inherited deficiency of factor X (FX) might be incompatible with perinatal survival. AIM: To provide experimental evidence about the null/close-to-null FX function. METHODS: The residual secreted (ELISA) and functional (thrombin generation assays) protein levels associated with the novel nonsense (c.1382G>A; p.Trp461Ter) and missense (c.752T>C; p.Leu251Pro) variants, found in the proposita with life-threatening symptoms at birth, were characterized through recombinant (r)FX expression. RESULTS: The rFX-461Ter showed very low secretion and undetectable function. Expression and function of the predicted readthrough-deriving missense variants (rFX-461Tyr, rFX-461Gln) were also severely impaired. These unfavourable features, due to nucleotide and protein sequence constraints, precluded functional readthrough over the 461 stop codon. Differently, the poorly secreted rFX-251Pro variant displayed residual function that was characterized by anti-TFPI aptamer-based amplification or selective inhibition of activated FX function by fondaparinux in plasma and found to be reduced by approximately three orders of magnitude. Similarly to the rFX-251Pro, a group of catalytic domain missense variants cause poorly secreted molecules with modest function in FX-deficient patients with life-threatening symptoms. CONCLUSIONS: Our data, contributing to the knowledge of the very severe FX deficiency forms, support life-saving requirement of trace FX function, clearly exemplified by the dysfunctional but not completely inactive rFX-251Pro variant that, albeit with severely reduced function, is compatible with a residual activity ensuring minimal haemostasis and permitting perinatal survival.
Asunto(s)
Dominio Catalítico/genética , Factor X/genética , Factor X/metabolismo , Hemorragias Intracraneales/genética , Mutación Missense , Secuencia de Aminoácidos , Factor X/química , Regulación de la Expresión Génica , Células HEK293 , Humanos , Recién Nacido , Hemorragias Intracraneales/metabolismo , Hemorragias Intracraneales/prevención & control , FenotipoRESUMEN
BACKGROUND AND OBJECTIVE: Community-acquired pneumonia (CAP) is associated with an increased risk of arterial and venous thrombosis but the underlying pathophysiological mechanisms are still unclear. We investigated if, in patients with CAP, a pro-thrombotic state does exist and its relationship with serum levels of endotoxins. METHODS: A total of 104 consecutive patients with CAP were prospectively recruited and followed up until discharge. At admission and at discharge, serum endotoxins, systemic markers of clotting activation and zonulin, a marker of gut permeability, were analysed. Hospitalized patients matched for gender, age and comorbidities but without infections were used as control. RESULTS: At admission, CAP patients showed higher plasma levels of F1+2 , a marker of thrombin generation (P = 0.023), and lower levels of protein C (PC; P < 0.001) and activated PC (aPC) (P < 0.001) compared with controls. At discharge, plasma levels of both PC and aPC significantly increased while F1+2 significantly decreased (P < 0.001). Baseline serum endotoxins and zonulin were higher in CAP patients than controls (P < 0.001) and significantly decreased at discharge; a significant correlation between serum endotoxins and zonulin was detected (R = 0.575; P < 0.001) CONCLUSION: This study provides the first evidence that CAP patients disclose an ongoing pro-thrombotic state and suggests a role for endotoxemia in determining enhanced thrombin generation.
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Coagulación Sanguínea , Toxina del Cólera/sangre , Infecciones Comunitarias Adquiridas , Endotoxemia/diagnóstico , Endotoxinas/sangre , Mucosa Intestinal/metabolismo , Neumonía , Trombosis , Anciano , Biomarcadores/sangre , Pruebas de Coagulación Sanguínea/métodos , Infecciones Comunitarias Adquiridas/sangre , Infecciones Comunitarias Adquiridas/complicaciones , Infecciones Comunitarias Adquiridas/fisiopatología , Femenino , Haptoglobinas , Hospitalización/estadística & datos numéricos , Humanos , Italia , Masculino , Persona de Mediana Edad , Permeabilidad , Neumonía/sangre , Neumonía/complicaciones , Neumonía/fisiopatología , Estudios Prospectivos , Precursores de Proteínas , Trombosis/diagnóstico , Trombosis/etiología , Trombosis/prevención & controlRESUMEN
Gene therapy may provide a cure for hemophilia and overcome the limitations of protein replacement therapy. Increasing the potency of gene transfer vectors may allow improvement of their therapeutic index, as lower doses can be administered to achieve therapeutic benefit, reducing toxicity of in vivo administration. Here we generated codon-usage optimized and hyperfunctional factor IX (FIX) transgenes carrying an R338L amino acid substitution (FIX Padua), previously associated with clotting hyperactivity and thrombophilia. We delivered these transgenes to hemophilia B mice by hepatocyte-targeted integration-competent and -defective lentiviral vectors. The hyperfunctional FIX transgenes increased FIX activity reconstituted in the plasma without detectable adverse effects, allowing correction of the disease phenotype at lower vector doses and resulting in improved hemostasis in vivo. The combined effect of codon optimization with the hyperactivating FIX-R338L mutation resulted in a robust 15-fold gain in potency and therefore provides a promising strategy to improve the efficacy, feasibility, and safety of hemophilia gene therapy.
Asunto(s)
Factor IX/genética , Terapia Genética/métodos , Hemofilia B/terapia , Mutación , Sustitución de Aminoácidos , Animales , Coagulación Sanguínea/genética , Coagulación Sanguínea/fisiología , Perros , Factor IX/fisiología , Estudios de Factibilidad , Vectores Genéticos/genética , Hemofilia B/genética , Humanos , Lentivirus/genética , Ratones , Tiempo de Tromboplastina Parcial , Resultado del TratamientoRESUMEN
BACKGROUND: Recent studies in healthy mice and rats have reported that positive pressure ventilation delivered with physiological tidal volumes at normal end-expiratory volume worsens lung mechanics and induces cytokine release, thus suggesting that detrimental effects are due to positive pressure ventilation per se. The aim of this study in healthy animals is to assess whether these adverse outcomes depend on the mode of mechanical ventilation. METHODS: Rats were subjected to 4 h of spontaneous, positive pressure, and whole-body or thorax-only negative pressure ventilation (N = 8 per group). In all instances the ventilatory pattern was that of spontaneous breathing. Lung mechanics, cytokines concentration in serum and broncho-alveolar lavage fluid, lung wet-to-dry ratio, and histology were assessed. Values from eight animals euthanized shortly after anesthesia served as control. RESULTS: No evidence of mechanical ventilation-dependent lung injury was found in terms of lung mechanics, histology, or wet-to-dry ratio. Relative to control, cytokine levels and recruitment of polymorphonuclear leucocytes increased slightly, and to the same extent with spontaneous, positive pressure, and whole-body negative pressure ventilation. Thorax-only negative pressure ventilation caused marked chest and lung distortion, reversible increase of lung elastance, and higher polymorphonuclear leucocyte count and cytokine levels. CONCLUSION: Both positive and negative pressure ventilation performed with tidal volumes and timing of spontaneous, quiet breathing neither elicit an inflammatory response nor cause morpho-functional alterations in normal animals, thus supporting the notion of the presence of a critical volume threshold above which acute lung injury ensues. Distortion of lung parenchyma can induce an inflammatory response, even in the absence of volotrauma.
Asunto(s)
Pulmón/fisiología , Modelos Animales , Respiración Artificial/métodos , Respiración Artificial/veterinaria , Mecánica Respiratoria/fisiología , Animales , Líquido del Lavado Bronquioalveolar , Citocinas/sangre , Citocinas/metabolismo , Femenino , Masculino , Respiración con Presión Positiva , Embarazo , Ratas , Ratas Sprague-Dawley , Valores de Referencia , Respiración , Volumen de Ventilación Pulmonar/fisiología , Ventiladores de Presión NegativaRESUMEN
BACKGROUND: Platelet activation at the early stage of COVID-19 is poorly described. The need for antiplatelet therapy in patients with COVID-19 remains controversial. We characterized the platelet activation profile in hospitalized patients at the early stage of COVID-19 using the modified prothrombinase Platelet Activation State (PAS) Assay. METHODS: Sixteen patients admitted to the emergency department of the IRCCS San Raffaele Hospital (Milan, Italy) between February 8 and April 2021 were enrolled. All patients presented with respiratory symptoms and tested positive for severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). Platelet activation was measured via the PAS Assay within 24 hours from patients' hospital admission. Data were compared with those measured in N.=24 healthy subjects (controls). RESULTS: Platelet activation was significantly higher in COVID-19 patients with respect to controls (PAS=0.63 [0.58-0.98%] vs. 0.46 [0.40-0.65%], respectively; P=0.03). Of note, highest PAS values were measured in the two patients with the worst clinical outcome, i.e., death because of respiratory failure (PAS=2.09% and 1.20%, respectively). No differences in standard coagulation parameters were noted between these two patients and those who were later discharged home. CONCLUSIONS: This study provides evidence of significant platelet activation state at the early stage of COVID-19 and suggests that the patient-specific platelet activation profile is a reliable clinical marker to stratify COVID-19 patients at high risk of poor clinical outcome who might potentially benefit from antiplatelet therapy.
Asunto(s)
COVID-19 , Hospitalización , Humanos , Activación Plaquetaria , Inhibidores de Agregación Plaquetaria/uso terapéutico , SARS-CoV-2RESUMEN
OBJECTIVES: To evaluate the competing pro-haemorrhagic contribution of acquired von Willebrand (vW) disease and antithrombotic therapy in patients implanted with continuous-flow left ventricular assist devices (LVADs). METHODS: We compared the extent of vW factor (vWf) degradation [vWf antigen (vWf:Ag)] and a decrease of functional activity of large vWf multimers [vWf collagen binding (vWf:CB)] in LVAD patients who did and did not suffer from bleeding. Data were measured pre-implant, at short-term (t1: <3 months) and long-term (t2: >12 months) follow-up. The occurrence of primary bleeding events, as well as bleeding recurrence, was correlated with patient-specific vWf profile and antithrombotic regimen. Indeed, patients were discharged on warfarin (international normalized ratio: 2-2.5) and aspirin, with the latter withhold after a first bleeding episode. RESULTS: Fifty-three patients were enrolled. The median follow-up was 324 (226-468) days. We recorded 25 primary bleeding events (47% of patients). All primary events occurred in patients on warfarin and aspirin. Both vWf:Ag and vWf:CB decreased significantly post-implant (P = 0.0003 and P < 0.0001), and patients showing pathological vWf:CB/vWf:Ag ratio (<0.7) increased progressively over the time of support (pre-implant = 26%, t1 = 58%, t2 = 74%; P < 0.0001). Of note, activity of large vWf multimers of bleeders was significantly lower at t2 with respect to non-bleeders (vWf:CB: 61 (36-115) vs 100 (68-121), P = 0.04; vWf:CB/vWf:Ag ratio: 0.36 (0.26-0.61) vs 0.58 (0.33-0.96), P = 0.04). Despite these marked differences in the vWf profile, following aspirin discontinuation only 3 patients had bleeding recurrence. CONCLUSIONS: Aspirin contributes significantly to haemorrhagic events in the background of acquired vW disease; its discontinuation significantly reduces bleeding recurrence. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03255928; ClinicalTrials.gov Identifier: NCT03255928.
Asunto(s)
Corazón Auxiliar , Hemorragia , Aspirina/efectos adversos , Fibrinolíticos/efectos adversos , Corazón Auxiliar/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Hemorragia/prevención & control , Humanos , Warfarina/efectos adversos , Enfermedades de von Willebrand/etiología , Factor de von Willebrand/metabolismoRESUMEN
OBJECTIVE: To see whether in acute lung injury 1) compression of the lungs caused by thoracoabdominal constriction degrades lung function and worsens ventilator-induced lung injury; and 2) maintaining end-expiratory transpulmonary pressure by increasing positive end-expiratory pressure reduces the deleterious effects of chest wall constriction. DESIGN: Experimental study in rats. SETTING: Physiology laboratory. INTERVENTIONS: Acute lung injury was induced in three groups of nine rats by saline lavage. Nine animals immediately killed served as a control group. Group L had lavage only, group LC had the chest wall constricted with an elastic binder, and group LCP had the same chest constriction but with positive end-expiratory pressure raised to maintain end-expiratory transpulmonary pressure. After lavage, all groups were ventilated with the same pattern for 1½ hrs. MEASUREMENTS AND MAIN RESULTS: Transpulmonary pressure, measured with an esophageal balloon catheter, lung volume changes, arterial blood gasses, and pH were assessed during mechanical ventilation. Lung wet-to-dry ratio, albumin, tumor necrosis factor-α, interleukin-1ß, interleukin-6, interleukin-10, and macrophage inflammatory protein-2 in serum and bronchoalveolar lavage fluid and serum E-selectin and von Willebrand Factor were measured at the end of mechanical ventilation. Lavage caused hypoxemia and acidemia, increased lung resistance and elastance, and decreased end-expiratory lung volume. With prolonged mechanical ventilation, lung mechanics, hypoxemia, and wet-to-dry ratio were significantly worse in group LC. Proinflammatory cytokines except E-selectin were elevated in serum and bronchoalveolar lavage fluid in all groups with significantly greater levels of tumor necrosis factor-α, interleukin-1ß, and interleukin-6 in group LC, which also exhibited significantly worse bronchiolar injury and greater heterogeneity of airspace expansion at a fixed transpulmonary pressure than other groups. CONCLUSIONS: Chest wall constriction in acute lung injury reduces lung volume, worsens hypoxemia, and increases pulmonary edema, mechanical abnormalities, proinflammatory mediator release, and histologic signs of ventilator-induced lung injury. Maintaining end-expiratory transpulmonary pressure at preconstriction levels by adding positive end-expiratory pressure prevents these deleterious effects.
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Respiración con Presión Positiva/métodos , Surfactantes Pulmonares/metabolismo , Lesión Pulmonar Inducida por Ventilación Mecánica/fisiopatología , Lesión Pulmonar Inducida por Ventilación Mecánica/terapia , Análisis de Varianza , Animales , Líquido del Lavado Bronquioalveolar/química , Constricción Patológica , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Masculino , Prevención Primaria/métodos , Intercambio Gaseoso Pulmonar , Distribución Aleatoria , Ratas , Valores de Referencia , Mecánica Respiratoria , Estadísticas no Paramétricas , Pared Torácica , Volumen de Ventilación PulmonarRESUMEN
Sixty-three, open-chest normal rats were subjected to mechanical ventilation (MV) with tidal volumes (VT) ranging from 7.5-39.5mlâ¯kg-1 and PEEP 2.3â¯cmH2O. Arterial blood gasses and pressure, and lung mechanics were measured during baseline ventilation (VTâ¯=â¯7.5mlâ¯kg-1) before and after test ventilation, when cytokine, von Willebrand factor (vWF), and albumin concentration in serum and broncho-alveolar lavage fluid (BALF), wet-to-dry weight ratio (W/D), and histologic injury scores were assessed. Elevation of W/D and serum vWF and cytokine concentration occurred with VTâ¯>â¯25mlâ¯kg-1. With VTâ¯>â¯30mlâ¯kg-1 cytokine and albumin concentration increased also in BALF, arterial oxygen tension decreased, lung mechanics and histology deteriorated, while W/D and vWF and cytokine concentration increased further. Hence, the initial manifestation of injurious MV consists of damage of extra-alveolar vessels leading to interstitial edema, as shown by elevated vWF and cytokine levels in serum but not in BALF. Failure of the endothelial-epithelial barrier occurs at higher stress-strain levels, with alveolar edema, small airway injury, and mechanical alterations.
Asunto(s)
Citocinas/sangre , Lesión Pulmonar , Edema Pulmonar , Respiración Artificial/efectos adversos , Mecánica Respiratoria/fisiología , Factor de von Willebrand , Animales , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Lesión Pulmonar/sangre , Lesión Pulmonar/etiología , Lesión Pulmonar/patología , Lesión Pulmonar/fisiopatología , Masculino , Edema Pulmonar/sangre , Edema Pulmonar/etiología , Edema Pulmonar/patología , Edema Pulmonar/fisiopatología , Ratas , Ratas Sprague-Dawley , Volumen de Ventilación Pulmonar/fisiologíaRESUMEN
We characterized the biologic background of prothrombotic platelet function in the setting of durable left ventricular assist devices (LVADs) evaluating the role of different antithrombotic regimens. Platelet-mediated thrombin generation was quantified using the Platelet Activity State (PAS) Assay and the Thrombin Generation Test (TGT) in 78 patients implanted with the HeartMate II (n = 10, 13%), the HeartMate 3 (HM3) (n = 30, 38%), or the HVAD (n = 38, 49%) and managed with oral anticoagulation plus aspirin (n = 46, 59%) or anticoagulation alone (n = 32, 41%). Coagulation parameters (platelet count, International Normalized Ratio (INR), activated Partial Thromboplastin Time, Fibrinogen and D-Dimer levels) and hemolysis (lactate dehydrogenase levels [LDH]) were also recorded to comprehensively characterize the hemostatic profile in the two groups. In patients without aspirin, the PAS assay revealed low-intensity increase in platelet prothrombinase activity (1.11-fold, p = 0.03). Similarly the TGT revealed moderate higher platelet reactivity when compared with patients receiving aspirin, consistent with reduction in lag time (0.87-fold, p < 0.001), increase in peak of thrombin generation (1.5-fold, p = 0.002) and thrombin generation rate (2-fold, p = 0.02), but comparable endogenous thrombin potential (p = 0.50). Coagulation parameters and LDH were comparable in the two groups (p > 0.05). Moreover, no differences were noted in platelet prothrombinase activity of patients implanted with the HM3 or HVAD. Our results suggest that, in the setting of durable LVADs, aspirin minimally modulates the biochemical pathway of platelet-mediated thrombin generation. Accordingly, re-evaluation of current antithrombotic management criteria in patients stratified according to bleeding/thromboembolic risk might be safe and beneficial to prevent adverse events.
Asunto(s)
Plaquetas/fisiología , Fibrinolíticos/uso terapéutico , Corazón Auxiliar/efectos adversos , Trombina/biosíntesis , Anciano , Coagulación Sanguínea/efectos de los fármacos , Femenino , Productos de Degradación de Fibrina-Fibrinógeno , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Lung morpho-functional alterations and inflammatory response to various types of mechanical ventilation (MV) have been assessed in normal, anesthetized, open-chest rats. Measurements were taken during protective MV [tidal volume (Vt) = 8 ml/kg; positive end-expiratory pressure (PEEP) = 2.6 cmH(2)O] before and after a 2- to 2.5-h period of ventilation on PEEP (control group), zero EEP without (ZEEP group) or with administration of dioctylsodiumsulfosuccinate (ZEEP-DOSS group), on negative EEP (NEEP group), or with large Vt (26 ml/kg) on PEEP (Hi-Vt group). No change in lung mechanics occurred in the Control group. Relative to the initial period of MV on PEEP, airway resistance increased by 33 +/- 4, 49 +/- 9, 573 +/- 84, and 13 +/- 4%, and quasi-static elastance by 19 +/- 3, 35 +/- 7, 248 +/- 12, and 20 +/- 3% in the ZEEP, NEEP, ZEEP-DOSS, and Hi-Vt groups. Relative to Control, all groups ventilated from low lung volumes exhibited histologic signs of bronchiolar injury, more marked in the NEEP and ZEEP-DOSS groups. Parenchymal and vascular injury occurred in the ZEEP-DOSS and Hi-Vt groups. Pro-inflammatory cytokine concentration in the bronchoalveolar lavage fluid (BALF) was similar in the Control and ZEEP group, but increased in all other groups, and higher in the ZEEP-DOSS and Hi-Vt groups. Interrupter resistance was correlated with indexes of bronchiolar damage, and cytokine levels with vascular-alveolar damage, as indexed by lung wet-to-dry ratio. Hence, protective MV from resting lung volume causes mechanical alterations and small airway injury, but no cytokine release, which seems mainly related to stress-related damage of endothelial-alveolar cells. Enhanced small airway epithelial damage with induced surfactant dysfunction or MV on NEEP can, however, contribute to cytokine production.
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Citocinas/metabolismo , Enfermedades Pulmonares/etiología , Pulmón/fisiopatología , Respiración con Presión Positiva/efectos adversos , Mecánica Respiratoria , Ventiladores de Presión Negativa/efectos adversos , Resistencia de las Vías Respiratorias , Animales , Líquido del Lavado Bronquioalveolar/química , Dióxido de Carbono/sangre , Detergentes/farmacología , Combinación de Medicamentos , Concentración de Iones de Hidrógeno , Isatina/análogos & derivados , Isatina/farmacología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Rendimiento Pulmonar , Enfermedades Pulmonares/metabolismo , Enfermedades Pulmonares/patología , Enfermedades Pulmonares/fisiopatología , Masculino , Oxígeno/sangre , Edema Pulmonar/etiología , Edema Pulmonar/metabolismo , Edema Pulmonar/fisiopatología , Piridinas/farmacología , Ratas , Ratas Sprague-Dawley , Succinatos/farmacología , Volumen de Ventilación Pulmonar , Regulación hacia ArribaRESUMEN
The mechanisms involved in the fall of exhaled nitric oxide (NOe) concentration occurring in normal, anesthetized open chest rabbits with prolonged mechanical ventilation (MV) at low lung volume have been investigated. NOe, pH of exhaled vapor condensate, serum prostaglandin E(2), and F(2alpha), tumor necrosis factor (TNF-alpha), PaO(2), PaCO(2), pHa, and lung mechanics were assessed before, during, and after 3-4h of MV at zero end-expiratory pressure (ZEEP), with fixed tidal volume (9 ml kg(-1)) and frequency, as well as before and after 3-4h of MV on PEEP only. Lung histology and wet-to-dry ratio (W/D), and prostaglandin and TNF-alpha in bronchoalveolar lavage fluid (BALF) were also assessed. While MV on PEEP had no effect on the parameters above, MV on ZEEP caused a marked fall (45%) of NOe, with a persistent increase of airway resistance (45%) and lung elastance (12%). Changes in NOe were independent of prostaglandin and TNF-alpha levels, systemic hypoxia, hypercapnia and acidosis, bronchiolar and alveolar interstitial edema, and pH of exhaled vapor condensate. In contrast, there was a significant relationship between the decrease in NOe and bronchiolar epithelial injury score. This indicates that the fall in NOe, which occurs in the absence of an inflammatory response, is due to the epithelial damage caused by the abnormal stresses related to cyclic opening and closing of small airways with MV on ZEEP, and suggests its use as a sign of peripheral airway injury.
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Resistencia de las Vías Respiratorias/fisiología , Enfermedades Pulmonares/fisiopatología , Óxido Nítrico/metabolismo , Respiración Artificial/efectos adversos , Mecánica Respiratoria , Animales , Líquido del Lavado Bronquioalveolar , Dióxido de Carbono/metabolismo , Dinoprost/metabolismo , Dinoprostona/metabolismo , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/metabolismo , Consumo de Oxígeno , Respiración con Presión Positiva/efectos adversos , Respiración con Presión Positiva/métodos , Intercambio Gaseoso Pulmonar , Conejos , Respiración Artificial/métodos , Método Simple Ciego , Volumen de Ventilación Pulmonar , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
In patients with left ventricular assist device support and aspirin allergy, the choice of effective antiplatelet strategy remains a challenge. We compared the antithrombotic effect of clopidogrel vs ticagrelor in an LVAD patient with aspirin allergy by using a modified protocol of the thrombin generation test, accounting selectively for the platelet contribution on thrombin generation. Our results demonstrate enhanced antithrombotic efficacy offered by ticagrelor. Consistent with experimental results, the patient has passed more than 300 days without thromboembolic complications. This study provides additional mechanistic rationale supporting clinical evidence and opens the perspective to identify individual poor responsiveness to drugs by specifically evaluating drug-mediated platelet function.
Asunto(s)
Aspirina/efectos adversos , Corazón Auxiliar , Inhibidores de Agregación Plaquetaria/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Trombosis/prevención & control , Ticlopidina/análogos & derivados , Warfarina/uso terapéutico , Clopidogrel , Hipersensibilidad a las Drogas , Quimioterapia Combinada , Insuficiencia Cardíaca/cirugía , Humanos , Masculino , Persona de Mediana Edad , Ticlopidina/uso terapéuticoRESUMEN
AIMS: To correlate the dynamics of platelet activation with the development of thromboembolic events in patients with continuous-flow left ventricular assist device (cf-LVAD). METHODS AND RESULTS: The platelet activity state (PAS) assay was utilized to evaluate platelet activation in 68 cf-LVAD patients implanted with the HeartMate II (n = 15, 22%), HeartMate 3 (n = 15, 22%), or HeartWare HVAD (n = 38, 56%). PAS was measured preoperatively, early post-implant, and at long-term follow-up (1, 3, 6, 12, 18, and 24 months post-implant). PAS was also measured at the occurrence of adverse events in patients who developed thrombotic complications. Data on patient demographics, medical history, antithrombotic therapy, and coagulation parameters were also analysed. Over a median follow-up of 602 (234-942) days, PAS values did not increase over time in the overall population (P = 0.15). However, PAS measured at event was 15-fold higher in the six patients (9%) who suffered pump thrombosis (n = 2) or ischaemic stroke (n = 4) vs. the rest of the population [6.67% (5.59%-11.98%) vs. 0.45% (0.33%-0.75%); P = 0.012], despite comparable coagulation profile. Pre-implant PAS values were 4.5-fold higher in these patients [1.90% (1.24%-3.17%) vs. 0.42% (0.32%-0.72%); P = 0.006]. Neither preoperative variables nor the type of the pump or the antiplatelet strategy were associated with a higher risk of complications. CONCLUSIONS: Thrombotic events are associated with altered PAS values. Moreover, baseline elevated PAS values in patients who developed thrombotic events suggest patient-specific tendency to post-implant thromboembolic complications. Prospectively, systematic monitoring of PAS might guide the development of refined patient-tailored antithrombotic strategies and the technological improvement of LVAD design.
Asunto(s)
Plaquetas/fisiología , Insuficiencia Cardíaca/terapia , Corazón Auxiliar/efectos adversos , Activación Plaquetaria/fisiología , Complicaciones Posoperatorias , Tromboembolia/sangre , Anciano , Biomarcadores/sangre , Estudios Transversales , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/sangre , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tromboembolia/epidemiología , Tromboembolia/etiologíaRESUMEN
To evaluate the effects of kidney-pancreas transplantation on hemostatic abnormalities in uremic type 1 diabetic patients, we conducted a cross-sectional study involving 12 type 1 diabetic patients, 30 uremic type 1 diabetic patients, 27 uremic type 1 diabetic patients who had a kidney-pancreas transplant, 12 uremic type 1 diabetic patients who had a kidney-alone transplant, and 13 healthy control subjects. We evaluated platelet and clotting system. Platelets in the group of uremic type 1 diabetic patients were significantly larger than platelets in the other groups. Resting calcium levels were significantly higher in the uremic type 1 diabetic patients and uremic type 1 diabetic patients who had a kidney-alone transplant than in the type 1 diabetic patients who had a kidney-pancreas transplant and control subjects. CD41 expression was significantly reduced in platelets from the uremic type 1 diabetic patients compared with the other groups. Levels of hypercoagulability markers in the type 1 diabetic patients who had a kidney-pancreas transplant and, to a lesser extent, the uremic type 1 diabetic patients who had a kidney-alone transplant but not the uremic type 1 diabetic patients were similar to those of the control subjects. A reduction in natural anticoagulants was evident in the uremic type 1 diabetic patients, whereas near-normal values were observed in the type 1 diabetic patients who had a kidney-pancreas transplant and uremic type 1 diabetic patients who had a kidney-alone transplant. Hemostatic abnormalities were not observed in type 1 diabetic patients who had a kidney-pancreas transplant. This finding might explain the lower cardiovascular death rate observed in type 1 diabetic patients who had a kidney-pancreas transplant compared with uremic type 1 diabetic patients who had a kidney-alone transplant or uremic type 1 diabetic patients.
Asunto(s)
Trastornos de la Coagulación Sanguínea/complicaciones , Diabetes Mellitus Tipo 1/sangre , Trasplante de Riñón , Trasplante de Páncreas , Uremia/sangre , Adulto , Coagulación Sanguínea , Trastornos de la Coagulación Sanguínea/sangre , Plaquetas/metabolismo , Calcio/metabolismo , Estudios Transversales , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial , Glicoproteína IIb de Membrana Plaquetaria/metabolismo , Tiempo de Protrombina , Receptor PAR-1/metabolismo , Receptores de Trombina/metabolismo , Transducción de Señal , Uremia/complicaciones , Uremia/cirugíaRESUMEN
Lung mechanics, exhaled NO (NOe), and TNF-alpha in serum and bronchoalveolar lavage fluid were assessed in eight closed and eight open chest, normal anesthetized rabbits undergoing prolonged (3-4 h) mechanical ventilation (MV) at low volume with physiological tidal volumes (10 ml/kg). Relative to initial MV on positive end-expiratory pressure (PEEP), MV at low volume increased lung quasi-static elastance (+267 and +281%), airway (+471 and +382%) and viscolelastic resistance (+480 and +294%), and decreased NOe (-42 and -25%) in closed and open chest rabbits, respectively. After restoration of PEEP, viscoelastic resistance returned to control, whereas airway resistance remained elevated (+120 and +31%) and NOe low (-25 and -20%) in both groups of rabbits. Elastance remained elevated (+23%) only in closed-chest animals, being associated with interstitial pulmonary edema, as reflected by increased lung wet-to-dry weight ratio with normal albumin concentration in bronchoalveolar lavage fluid. In contrast, in 16 additional closed- and open-chest rabbits, there were no changes of lung mechanics or NOe after prolonged MV on PEEP only. At the end of prolonged MV, TNF-alpha was practically undetectable in serum, whereas its concentration in bronchoalveolar lavage fluid was low and similar in animals subjected or not subjected to ventilation at low volume (62 vs. 43 pg/ml). These results indicate that mechanical injury of peripheral airways due to their cyclic opening and closing during ventilation at low volume results in changes in lung mechanics and reduction in NOe and that these alterations are not mediated by a proinflammatory process, since this is expressed by TNF-alpha levels.
Asunto(s)
Pulmón/fisiopatología , Óxido Nítrico/metabolismo , Neumonía/fisiopatología , Respiración Artificial/efectos adversos , Síndrome de Dificultad Respiratoria/fisiopatología , Mecánica Respiratoria , Animales , Espiración , Volumen Espiratorio Forzado , Lesión Pulmonar , Neumonía/etiología , Intercambio Gaseoso Pulmonar , Conejos , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria/etiologíaRESUMEN
OBJECTIVES: Bleeding and inflammation are major complications of extracorporeal circulation. Off-pump coronary artery bypass grafting may reduce the rate of complications, but it can only be applied in selected cases. Pilot studies have shown a potential benefit from the use of antifibrinolytic drugs, but efficacy in randomized double-blind studies evaluating off- and on-pump coronary artery bypass grafting has not been proved. METHODS: We enrolled 102 patients scheduled for on-pump (n = 51) or off-pump (n = 51) coronary artery bypass grafting. Patients were separately double-blind randomly assigned to treatment with tranexamic acid (1 g as 20-minute bolus before skin incision, followed by continuous infusion of 400 mg/h, with 500 mg added to priming in patients undergoing on-pump coronary artery bypass grafting) or placebo (saline solution of equivalent volume). Bleeding in the first 24 postoperative hours was the primary outcome. Requirement for allogeneic transfusions, thrombotic complications, outcomes, and monitoring of coagulation, fibrinolysis, and inflammation were also recorded. RESULTS: Tranexamic acid reduced total postoperative bleeding by 43% in patients undergoing on-pump coronary artery bypass grafting and by 27% in those undergoing off-pump coronary artery bypass grafting (P <.0001), with 80% reduction in bleeding exceeding 600 mL (P <.001), 58% reduction in the requirement for all allogeneic transfusions (P =.07), and no apparent effect on thrombotic complications or outcome. This was associated with a reduction in plasma D-dimer levels (P <.0001), to a greater degree in patients undergoing on-pump coronary artery bypass grafting (P <.0001), and interleukin 6 levels (P <.0001), to a greater degree in patients undergoing off-pump coronary artery bypass grafting (P <.001). CONCLUSIONS: By affecting fibrinolysis, tranexamic acid significantly reduces bleeding both in off- and on-pump coronary artery bypass grafting and may modulate inflammation in these surgical settings.