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1.
New Phytol ; 230(4): 1394-1406, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33525059

RESUMEN

The impact of extreme climate episodes such as heatwaves on plants physiological functioning and survival may depend on the event intensity, which requires quantification. We unraveled the distinct impacts of intense (HW) and intermediate (INT) heatwave days on carbon uptake, and the underlying changes in the photosynthetic system, in a Mediterranean citrus orchard using leaf active (pulse amplitude modulation; PAM) and canopy level passive (sun-induced; SIF) fluorescence measurements, together with CO2 , water vapor, and carbonyl sulfide (COS) exchange measurements. Compared to normal (N) days, gross CO2 uptake fluxes (gross primary production, GPP) were significantly reduced during HW days, but only slightly decreased during INT days. By contrast, COS uptake flux and SIFA (at 760 nm) decreased during both HW and INT days, which was reflected in leaf internal CO2 concentrations and in nonphotochemical quenching, respectively. Intense (HW) heatwave conditions also resulted in a substantial decrease in electron transport rates, measured using leaf-scale fluorescence, and an increase in the fractional energy consumption in photorespiration. Using the combined proxy approach, we demonstrate a differential ecosystem response to different heatwave intensities, which allows the trees to preserve carbon assimilation during INT days but not during HW days.


Asunto(s)
Dióxido de Carbono , Citrus , Ecosistema , Fluorescencia , Fotosíntesis , Óxidos de Azufre
2.
J Hepatol ; 65(4): 692-699, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27242316

RESUMEN

BACKGROUND & AIMS: We aimed to investigate the impact of sustained virologic response (SVR) to interferon (IFN)-free therapies on portal hypertension in patients with paired hepatic venous pressure gradient (HVPG) measurements. METHODS: One hundred and four patients with portal hypertension (HVPG ⩾6mmHg) who underwent HVPG and liver stiffness measurement before IFN-free therapy (baseline [BL]) were retrospectively studied. Among 100 patients who achieved SVR, 60 patients underwent HVPG and transient elastography (TE) after antiviral therapy (follow-up [FU]). RESULTS: SVR to IFN-free therapies significantly decreased HVPG across all BL HVPG strata: 6-9mmHg (BL: 7.37±0.28 vs. FU: 5.11±0.38mmHg; -2.26±0.42mmHg; p<0.001), 10-15mmHg (BL: 12.2±0.4 vs. FU: 8.91±0.62mmHg; -3.29±0.59mmHg; p<0.001) and ⩾16mmHg (BL: 19.4±0.73 vs. FU: 17.1±1.21mmHg; -2.3±0.89mmHg; p=0.018). In the subgroup of patients with BL HVPG of 6-9mmHg, HVPG normalized (<6mmHg) in 63% (12/19) of patients, while no patient progressed to ⩾10mmHg. Among patients with BL HVPG ⩾10mmHg, a clinically relevant HVPG decrease ⩾10% was observed in 63% (26/41); 24% (10/41) had a FU HVPG <10mmHg. Patients with Child-Pugh stage B were less likely to have a HVPG decrease (hazard ratio [HR]: 0.103; 95% confidence interval [CI]: 0.02-0.514; p=0.006), when compared to Child-Pugh A patients. In the subgroup of patients with BL CSPH, the relative change in liver stiffness (per %; HR: 0.972; 95% CI: 0.945-0.999; p=0.044) was a predictor of a HVPG decrease ⩾10%. The area under the receiver operating characteristic curve for the diagnosis of FU CSPH by FU liver stiffness was 0.931 (95% CI: 0.865-0.997). CONCLUSIONS: SVR to IFN-free therapies might ameliorate portal hypertension across all BL HVPG strata. However, changes in HVPG seemed to be more heterogeneous among patients with BL HVPG of ⩾16mmHg and a HVPG decrease was less likely in patients with more advanced liver dysfunction. TE might be useful for the non-invasive evaluation of portal hypertension after SVR. LAY SUMMARY: We investigated the impact of curing hepatitis C using novel interferon-free treatments on portal hypertension, which drives the development of liver-related complications and mortality. Cure of hepatitis C decreased portal pressure, but a decrease was less likely among patients with more pronounced hepatic dysfunction. Transient elastography, which is commonly used for the non-invasive staging of liver disease, might identify patients without clinically significant portal hypertension after successful treatment.


Asunto(s)
Hipertensión Portal , Diagnóstico por Imagen de Elasticidad , Hepatitis C , Humanos , Interferones , Cirrosis Hepática , Respuesta Virológica Sostenida
3.
Transpl Int ; 29(9): 999-1007, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27203857

RESUMEN

DAA-based regimens for chronic hepatitis C infection encourage treatment of "difficult-to-treat" cohorts. This study investigated efficacy and safety of DAA-based regimens in HCV patients on dialysis or postkidney or liver/kidney transplantation. Twenty-five patients treated with DAA combinations were evaluated: 10 were on dialysis (eight: hemodialysis, two: peritoneal dialysis), eight were kidney transplant recipients, and seven were liver/kidney transplant recipients. Except for one patient treated with daclatasvir ([DCV]/60 mg/QD)/simeprevir ([SMV]/150 mg/QD), the others received sofosbuvir-based regimens ([SOF];400 mg/QD) combined with SMV:eight, DCV:13 or either ledipasvir ([LDV]90 mg/QD), ribavirin ([RBV];weight based) or pegylated interferon/RBV. HCV-RNA was determined by Abbott RealTime (LLOQ]:12 IU/ml) or Roche AmpliPrep/COBAS TaqMan assay (LLOQ:15 IU/ml); treatment response evaluated every 4 weeks, at the end of treatment, and 4 and 12 weeks thereafter. Twenty-four (96%) patients achieved SVR 12/24 (ITT-analysis). Mean treatment duration was 15.1 ± 5.1 weeks (±SD), and two patients terminated prematurely - both reached SVR12. Six patients were hospitalized due to complications of underlying disease. One patient achieved SVR24 but was re-infected (week 27). Kidney function remained stable; serum creatinine increased in only one patient - SOF was reduced to 400 mg/48 h. Treatment with DAA combinations in renally impaired HCV patients is highly effective and well tolerated. These findings call for further controlled trials and data from real-life cohorts.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Trasplante de Riñón , Insuficiencia Renal/cirugía , Adulto , Anciano , Bencimidazoles/uso terapéutico , Carbamatos , Estudios de Cohortes , Quimioterapia Combinada , Femenino , Fluorenos/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/cirugía , Humanos , Imidazoles/uso terapéutico , Inmunosupresores/uso terapéutico , Riñón/patología , Pruebas de Función Renal , Hígado/patología , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Periodo Preoperatorio , Pirrolidinas , ARN Viral/genética , Diálisis Renal , Simeprevir/uso terapéutico , Sofosbuvir/uso terapéutico , Valina/análogos & derivados
4.
PNAS Nexus ; 2(11): pgad352, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38024393

RESUMEN

Suppression of carbon emissions through photovoltaic (PV) energy and carbon sequestration through afforestation provides complementary climate change mitigation (CCM) strategies. However, a quantification of the "break-even time" (BET) required to offset the warming impacts of the reduced surface reflectivity of incoming solar radiation (albedo effect) is needed, though seldom accounted for in CCM strategies. Here, we quantify the CCM potential of PV fields and afforestation, considering atmospheric carbon reductions, solar panel life cycle analysis (LCA), surface energy balance, and land area required across different climatic zones, with a focus on drylands, which offer the main remaining land area reserves for forestation aiming climate change mitigation (Rohatyn S, Yakir D, Rotenberg E, Carmel Y. Limited climate change mitigation potential through forestation of the vast dryland regions. 2022. Science 377:1436-1439). Results indicate a BET of PV fields of ∼2.5 years but >50× longer for dryland afforestation, even though the latter is more efficient at surface heat dissipation and local surface cooling. Furthermore, PV is ∼100× more efficient in atmospheric carbon mitigation. While the relative efficiency of afforestation compared with PV fields significantly increases in more mesic climates, PV field BET is still ∼20× faster than in afforestation, and land area required greatly exceeds availability for tree planting in a sufficient scale. Although this analysis focusing purely on the climatic radiative forcing perspective quantified an unambiguous advantage for the PV strategy over afforestation, both approaches must be combined and complementary, depending on climate zone, since forests provide crucial ecosystem, climate regulation, and even social services.

6.
Front Aging Neurosci ; 12: 50, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32194393

RESUMEN

Background: People with Parkinson's disease (PD) display poorer gait performance when walking under complex conditions than under simple conditions. Screening tests that evaluate gait performance changes under complex walking conditions may be valuable tools for early intervention, especially if allowing for massive data collection. Objectives: To investigate the use of the Goalkeeper Game (GG) to predict impairment in gait performance under complex conditions in people with Parkinson's disease (PPD) and compare its predictive power with the one of the Montreal Cognitive Assessment (MoCA) test. Methods: 74 PPD (HY stages: 23 in stage 1; 31 in stage 2; 20 in stage 3), without dementia (MoCA cut-off 21), tested in ON period with dopaminergic medication were submitted to single individual cognitive/motor evaluation sessions. MoCA and GG were used to assess cognition, and the dynamic gait index (DGI) test was used to assess gait performance under complex condition. GG test resulted in 9 measures extracted via a statistical model. The predictive power of the GG measures and the MoCA score with respect to gait performance, as assessed by DGI, were compared. Results: The predictive models based on GG obtained a better score of prediction (65%) then MoCA (56%) for DGI scores (at a 50% specificity). Conclusion: GG is a novel tool for noninvasive screening that showed a superior predictive power in assessing gait performance under complex condition in people with PD than the well-established MoCa test.

7.
Ultrasound Med Biol ; 44(12): 2578-2586, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30241728

RESUMEN

Elastography point quantification (ElastPQ) is a new ultrasound-based shear wave elastography method for non-invasive assessment of liver fibrosis. We evaluated the diagnostic accuracy of ElastPQ in patients with chronic viral hepatitis. Fibrosis stage (F) was determined by transient elastography (F0/F1: <7.1 kPa, F2: 7.1-9.4 kPa, F3: 9.5-12.4 kPa, F4: ≥12.5 kPa). Area under the receiver operator characteristics curve (AUROC) analysis was performed to assess ElastPQ cutoffs for significant fibrosis (≥F2) and cirrhosis (F4). Paired transient elastography and ElastPQ measurements were obtained from 217 patients (mean age ± SEM: 49 ± 0.79 years, 68.2% male, F0/F1: n = 98 [45.0%], F2: 47 [21.6%], F3: 22 [10.1%], F4: 50 [22.9%]). AUROC for ≥F2 was 0.843 (95% confidence interval: 0.791-0.895), and for F4, 0.933 (95% confidence interval: 0.894-0.972). The optimal ElastPQ cutoff for F2 was 6.68 kPa (sensitivity: 80.7%, specificity: 70.4%, positive predictive value: 78.5%, negative predictive value: 72.3%), and for F4 11.28 kPa (sensitivity: 86.0%, specificity: 85.6%, positive predictive value: 60.52%, negative predictive value: 97.16%). In conclusion, ElastPQ represents an accurate tool for non-invasive staging of liver fibrosis in patients with viral hepatitis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Hepatitis C Crónica/complicaciones , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/etiología , Estudios Transversales , Femenino , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
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