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1.
Clin Exp Dermatol ; 43(3): 300-302, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29277927

RESUMEN

We report a 23-year-old immunocompromised woman who, following cardiac transplantation, presented with an unusual cutaneous eruption. She developed a widespread pustular rash, systemic symptoms and a high temperature with raised inflammatory markers. The diagnosis was reached when a skin biopsy was cultured onto Legionella agar (buffered charcoal yeast extract) and Legionella feeleii was isolated. The patient was treated with 6 weeks of moxifloxacin and her cutaneous lesions gradually resolved. Cutaneous Legionella infections are uncommon and usually affect immunocompromised patients.


Asunto(s)
Huésped Inmunocomprometido , Legionella/aislamiento & purificación , Legionelosis/microbiología , Enfermedades Cutáneas Bacterianas/microbiología , Biopsia , Diagnóstico Diferencial , Femenino , Trasplante de Corazón , Humanos , Legionella/clasificación , Legionelosis/diagnóstico , Piel/microbiología , Piel/patología , Enfermedades Cutáneas Bacterianas/diagnóstico , Adulto Joven
2.
Am J Transplant ; 18(4): 916-926, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28980446

RESUMEN

The classical pathway (CP) of complement may contribute to the pathogenesis of antibody-mediated rejection (ABMR). Selective CP blockade may be a promising strategy to counteract rejection. The objective of this first-in-patient phase 1b trial was to evaluate the safety/tolerability and CP-blocking potential of 4 weekly doses (60 mg/kg) of the anti-C1s antibody BIVV009 in complement-mediated disorders. Here we describe the results in a cohort of 10 stable kidney transplant recipients (median of 4.3 years posttransplantation) with late active ABMR and features of CP activation, such as capillary C4d or complement-fixing donor-specific antibodies (DSA). During 7 weeks follow-up, no severe adverse events were reported, and BIVV009 profoundly inhibited overall and DSA-triggered CP activation in serum. Five of 8 C4d-positive recipients turned C4d-negative in 5-week follow-up biopsies, while another 2 recipients showed a substantial decrease in C4d scores. There was, however, no change in microcirculation inflammation, gene expression patterns, DSA levels, or kidney function. In conclusion, we demonstrate that BIVV009 effectively blocks alloantibody-triggered CP activation, even though short-course treatment had no effect on indices of activity in late ABMR. This initial trial provides a valuable basis for future studies designed to clarify the therapeutic value of CP blockade in transplantation. ClinicalTrials.gov NCT#02502903.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Complemento C1s/inmunología , Rechazo de Injerto/tratamiento farmacológico , Supervivencia de Injerto/efectos de los fármacos , Isoanticuerpos/efectos adversos , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Adulto , Anciano , Aloinjertos , Activación de Complemento/inmunología , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Rechazo de Injerto/patología , Supervivencia de Injerto/inmunología , Antígenos HLA/inmunología , Humanos , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Donantes de Tejidos
3.
Nano Lett ; 17(11): 6696-6701, 2017 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-29052998

RESUMEN

Structural quality and stability of nanocrystals are fundamental problems that bear important consequences for the performances of small-scale devices. Indeed, at the nanoscale, their functional properties are largely influenced by elastic strain and depend critically on the presence of crystal defects. It is thus of prime importance to be able to monitor, by noninvasive means, the stability of the microstructure of nano-objects against external stimuli such as mechanical load. Here we demonstrate the potential of Bragg coherent diffraction imaging for such measurements, by imaging in 3D the evolution of the microstructure of a nanocrystal exposed to in situ mechanical loading. Not only could we observe the evolution of the internal strain field after successive loadings, but we also evidenced a transient microstructure hosting a stable dislocation loop. The latter is fully characterized from its characteristic displacement field. The mechanical behavior of this small crystal is clearly at odds with what happens in bulk materials where many dislocations interact. Moreover, this original in situ experiment opens interesting possibilities for the investigation of plastic deformation at the nanoscale.

4.
Am J Transplant ; 17(9): 2300-2311, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28251805

RESUMEN

The classic pathway (CP) of complement is believed to significantly contribute to alloantibody-mediated transplant injury, and targeted complement inhibition is currently considered to be a promising approach for preventing rejection. Here, we investigated the mode of action and efficacy of the humanized anti-C1s monoclonal antibody TNT009 and its parental mouse variant, TNT003, in preclinical in vitro models of HLA antibody-triggered CP activation. In flow cytometric assays, we measured the attachment of C1 subcomponents and C4/C3 split products (C4b/d, C3b/d) to HLA antigen-coated flow beads or HLA-mismatched aortic endothelial cells and splenic lymphocytes. Anti-C1s antibodies profoundly inhibited C3 activation at concentrations >20 µg/mL, in both solid phase and cellular assays. While C4 activation was also prevented, this was not the case for C1 subcomponent attachment. Analysis of serum samples obtained from 68 sensitized transplant candidates revealed that the potency of inhibition was related to the extent of baseline CP activation. This study demonstrates that anti-C1s antibodies TNT009 and TNT003 are highly effective in blocking HLA antibody-triggered complement activation downstream of C1. Our results provide the foundation for clinical studies designed to investigate the potential of TNT009 in the treatment or prevention of complement-mediated tissue injury in sensitized transplant recipients.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Activación de Complemento/inmunología , Complemento C1s/inmunología , Rechazo de Injerto/tratamiento farmacológico , Antígenos HLA/inmunología , Isoanticuerpos/efectos adversos , Trasplante de Riñón/efectos adversos , Animales , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Fallo Renal Crónico/inmunología , Fallo Renal Crónico/cirugía , Pruebas de Función Renal , Ratones , Pronóstico
5.
Transplant Proc ; 48(10): 3387-3392, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27931586

RESUMEN

BACKGROUND: Methotrexate (MTX) is potential change in immunosuppression after lung transplantation that may help to slow down the decline in lung function in bronchiolitis obliterans syndrome (BOS). METHODS: We sought to analyze the safety and efficacy of MTX in patients with BOS, by retrospective case review. RESULTS: Thirty lung allograft patients were treated with MTX for BOS after one bilateral lower lobe, nine single, 16 bilateral, and four heart-lung transplants. Twenty-one patients had MTX treatment for a minimum of 6 months, and their serial lung function was analyzed for efficacy. In these patients, there was a significant overall increase in mean forced expiratory volume in 1 second (FEV1) of 149 mL (P < .02) at 3 months, with an increase observed in 14 of 21 patients. At 6 months, there was a mean increase in FEV1 of 117 mL (P < .05). At 12 months, there was a mean non-significant increase of FEV1 of 60 mL (P = .19) observed in 18 patients who had MTX for this time period. The rate of decline in FEV1 before MTX was 118.5 mL/month and at 3 months after MTX increased to 49.5 mL/months (P < .0005) in the FEV1. Nine patients had been treated with MTX for less than 6 months; two died within 6 months of starting MTX, five tolerated the drug poorly with nausea and tiredness, and one developed leucopenia. One patient requested discontinuation of the medication after failing to halt the rapid progressive decline in lung function after 1 month. CONCLUSIONS: Methotrexate therapy provides a potential therapeutic strategy in managing the progressive decline in lung function observed in BOS. This is hampered by the observation of poor tolerability and side effects.


Asunto(s)
Bronquiolitis Obliterante/tratamiento farmacológico , Terapia de Inmunosupresión/métodos , Inmunosupresores/administración & dosificación , Trasplante de Pulmón/efectos adversos , Metotrexato/administración & dosificación , Adolescente , Adulto , Bronquiolitis Obliterante/etiología , Bronquiolitis Obliterante/fisiopatología , Femenino , Volumen Espiratorio Forzado , Humanos , Leucopenia/etiología , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
6.
Philos Trans A Math Phys Eng Sci ; 374(2066)2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27002070

RESUMEN

I discuss various mathematical constructions that combine together to provide a natural setting for discrete and continuum geometric models of defective crystals. In particular, I provide a quite general list of 'plastic strain variables', which quantifies inelastic behaviour, and exhibit rigorous connections between discrete and continuous mathematical structures associated with crystalline materials that have a correspondingly general constitutive specification.

7.
BJOG ; 123(4): 588-97, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26542419

RESUMEN

OBJECTIVE: To assess whether antenatal exercise in overweight/obese women would improve maternal and perinatal outcomes. DESIGN: Two-arm parallel randomised controlled trial. SETTING: Home-based intervention in Auckland, New Zealand. POPULATION AND SAMPLE: Pregnant women with body mass index ≥25 kg/m(2) . METHODS: Participants were randomised to a 16-week moderate-intensity stationary cycling programme from 20 weeks of gestation, or to a control group with no exercise intervention. MAIN OUTCOME MEASURES: Primary outcome was offspring birthweight. Perinatal and maternal outcomes were assessed, with the latter including weight gain, aerobic fitness, quality of life, pregnancy outcomes, and postnatal body composition. Exercise compliance was recorded with heart rate monitors. RESULTS: Seventy-five participants were randomised in the study (intervention 38, control 37). Offspring birthweight (adjusted mean difference 104 g; P = 0.35) and perinatal outcomes were similar between groups. Aerobic fitness improved in the intervention group compared with controls (48.0-second improvement in test time to target heart rate; P = 0.019). There was no difference in weight gain, quality of life, pregnancy outcomes or postnatal maternal body composition between groups. However, compliance with exercise protocol was poor, with an average of 33% of exercise sessions completed. Sensitivity analyses showed that greater compliance was associated with improved fitness (increased test time (P = 0.002), greater VO2 peak (P = 0.015), and lower resting heart rate (P = 0.014)), reduced postnatal adiposity (reduced fat mass (P = 0.007) and body mass index (P = 0.035)) and better physical quality of life (P = 0.034). CONCLUSIONS: Maternal non-weight-bearing moderate-intensity exercise in pregnancy improved fitness but did not affect birthweight or clinical outcomes. TWEETABLE ABSTRACT: Moderate-intensity exercise in overweight/obese pregnant women improved fitness but had no clinical effects.


Asunto(s)
Terapia por Ejercicio , Obesidad/terapia , Sobrepeso/terapia , Mujeres Embarazadas , Atención Prenatal , Adulto , Índice de Masa Corporal , Femenino , Humanos , Nueva Zelanda/epidemiología , Obesidad/epidemiología , Obesidad/prevención & control , Sobrepeso/epidemiología , Sobrepeso/prevención & control , Cooperación del Paciente , Embarazo , Resultado del Embarazo , Mujeres Embarazadas/psicología , Calidad de Vida , Conducta de Reducción del Riesgo , Resultado del Tratamiento , Aumento de Peso
8.
Am J Transplant ; 15(8): 2037-49, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25904443

RESUMEN

Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Activación de Complemento/inmunología , Complemento C1s/inmunología , Antígenos HLA/inmunología , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/inmunología , Trasplante de Corazón , Humanos
9.
Artículo en Inglés | MEDLINE | ID: mdl-25679631

RESUMEN

The formation of donut- and croissantlike buckles has been observed onto the free surface of gold thin films deposited on silicon substrates. Numerical simulations clearly evidence that the coupling effect between the atmospheric pressure acting on the free surface and the plastic folding of the ductile film is responsible for the circular blister destabilization and the formation of the donut- and croissantlike buckling patterns.

10.
J Mech Behav Biomed Mater ; 10: 183-96, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22520430

RESUMEN

In this paper an analytical solution for the stress state in a coated stent is presented, with a particular focus on the interface stresses between the coating and stent. As a first step a simplified stent architecture consisting of a bi-layered composite elastic arch is considered. The variations of normal and shear stress at the interface as functions of the boundary conditions at the base of the arch are explored. Depending on applied displacement and rotation, very distinct distributions of stress occur along the interface: dominant shear or dominant normal stress, compressive or tensile normal stress. A bi-layered composite elastic strut is then added to the composite elastic arch in order to create a realistic coated stent geometry. A displacement is applied to the bottom of the strut to simulate stent deployment. The addition of the strut is found to increase the normal stress and decrease the shear stress at all points on the interface. The influence of the various geometrical and material parameters on interface stress is explored using the analytical procedure developed in the paper, providing practical insight for stent-coating design.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Stents , Estrés Mecánico , Elasticidad , Diseño de Equipo , Rotación , Resistencia al Corte
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