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1.
QJM ; 116(1): 57-62, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36047831

RESUMO

BACKGROUND: Underlying immunodeficiency is associated with severe COVID-19, but the prognosis of persons with human immunodeficiency virus (HIV) (PWH) with COVID-19 is under debate. Aim: assessment of the mortality rate and major determinants of death in HIV-infected patients hospitalized with COVID-19 in Spain before vaccine availability. Design: Retrospective nationwide public database analysis. METHODS: Nationwide, retrospective, observational analysis of all hospitalizations with COVID-19 during year 2020 in Spain. Stratification was made according to HIV status. The National Registry of Hospital Discharges was used with the ICD-10 coding list. RESULTS: A total of 117 694 adults were hospitalized with COVID-19 during 2020. Only 234 (0.2%) were HIV-positives. More than 95% were on antiretroviral therapy. Compared to HIV-negatives, PWH were younger (mean age 53.2 vs. 66.5 years old; P<0.001) and more frequently male (74.8% vs. 56.6%; P<0.001). Most co-morbidities predisposing to severe COVID-19 (diabetes, hypertension, dementia and cardiovascular disease) were more frequent in HIV-negatives. In contrast, the rate of baseline liver disease was over 6-fold higher in PWH (27.4% vs. 4.4%; P<0.001). In-hospital mortality was lower in PWH (9.4% vs. 16%; P=0.004). In multivariate analysis, older age, dementia and especially advanced liver disease (relative risk (RR): 7.6) were the major determinants of death in PWH hospitalized with COVID-19. CONCLUSION: HIV-infected patients hospitalized in Spain with COVID-19 during 2020 had better survival than HIV-negatives, most likely explained by younger age and lower rate of co-morbidities. However, advanced liver disease was a major predictor of death in PWH hospitalized with COVID-19.


Assuntos
COVID-19 , Demência , Infecções por HIV , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , COVID-19/complicações , HIV , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Mortalidade Hospitalar , Estudos Retrospectivos , Feminino
2.
Rev. esp. cardiol. (Ed. impr.) ; 75(5): 412-420, mayo 2022.
Artigo em Espanhol | IBECS | ID: ibc-205089

RESUMO

Introducción y objetivos: Una profundidad más alta del implante percutáneo de una válvula aórtica autoexpandible minimiza el daño en el sistema de conducción y puede reducir las tasas de marcapasos permanente a 30 días. El objetivo es determinar la seguridad y la eficacia de modificar la técnica de implante clásica para el reemplazo percutáneo de la válvula aórtica a una técnica de proyección de superposición de cúspides (PSC) para lograr una profundidad más alta del implante y reducir la necesidad de marcapasos permanente. Métodos: Desde marzo de 2017 se incluyó a 226 pacientes consecutivos: 113 tratados con técnica de implante PSC frente a 113 casos consecutivos previos con implante clásico. La profundidad del implante se evaluó mediante 3 métodos en todos los pacientes (cúspide no coronaria a válvula cardiaca percutánea (VCP); media de cúspide no coronaria y cúspide coronaria izquierda a VCP y el borde más profundo de cúspide coronaria izquierda y cúspide no coronaria a VCP). Resultados: El grupo de PSC presentó una profundidad del implante menor que el del grupo de implante clásico (4,8±2,2 frente a 5,7±3,1 mm; p=0,011; 5,8±3,1 frente a 6,5±2,4 mm; p=0,095; 7,1±2,8 frente a 7,4±3,2 mm; p=0,392). A los 30 días de seguimiento, 40 pacientes (17,7%) requirieron el implante de marcapasos permanente, menos en el grupo de PSC (el 12,4 frente al 23%; p=0,036). La técnica de implante PSC protegió contra el evento principal (OR=0,45; IC95%, 0,21-0,97; p=0,043), con parecidos éxito del procedimiento y complicaciones. Conclusiones: La técnica de implante PSC es una simple modificación en el protocolo que proporciona una profundidad del implante más alta de la prótesis valvular autoexpandible con menores alteraciones de la conducción y tasas de marcapasos permanente (AU)


Introduction and objectives: This study aimed to determine the safety and efficacy of modifying the classic implantation technique for aortic transcatheter heart valve (THV) implantation to a cusp-overlap-projection (COP) technique to achieve a higher implantation depth and to reduce the burden of new permanent pacemaker implantation (PPMI) at 30 days. Aortic self-expanding THV carries an elevated risk for PPMI. A higher implantation depth minimizes the damage in the conduction system and may reduce PPMI rates. Methods: From March 2017, 226 patients were consecutively included: 113 patients were treated using the COP implantation technique compared with the previous 113 consecutive patients treated using the classic technique. In all patients, implantation depth was assessed by 3 methods (noncoronary cusp to the THV, mean of the noncoronary cusp and the left coronary cusp to the THV, and the deepest edge from the left coronary cusp and the noncoronary cusp to the THV). Results: The COP group had a lower implantation depth than the group treated with the classic technique (4.8 mm± 2.2 vs 5.7 mm± 3.1; P=.011; 5.8 mm± 3.1 vs 6.5 mm± 2.4; P=.095; 7.1 mm± 2.8 vs 7.4 mm±3.2; P=.392). Forty patients (17.7%) required a new PPMI after the 30-day follow-up but this requirement was significantly lower in the COP group (12.4% vs 23%, P=.036). The COP implantation technique consistently protected against the main event (OR, 0.45; 95%CI, 0.21-0.97; P=.043), with similar procedural success rates and complications. Conclusions: The COP implantation technique is a simple modification of the implantation protocol and provides a higher implantation depth of self-expanding-THV with lower conduction disturbances and PPMI rates (AU)


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Estudos Prospectivos , Desenho de Prótese , Projetos Piloto , Resultado do Tratamento
3.
Tech Coloproctol ; 26(4): 261-270, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35091790

RESUMO

BACKGROUND: The aim of the present study was to demonstrate that transvaginal specimen extraction is a feasible and safe approach in colorectal resection for deep endometriosis (DE) and to assess the risk factors for postoperative complications. METHODS: This retrospective cohort study included all the consecutive patients undergoing segmental bowel resection for symptomatic endometriosis at "La Paz" University Hospital (Madrid, Spain) and at "Hospital General Universitario de Valencia" (Valencia, Spain) from January 2014 to December to 2017. Patients were grouped according to specimen extraction approach into those who had transvaginal extraction (Group I) and those who had suprapubic extraction (Group II). Clinic-demographical, surgical and post-surgical data were recorded. Intra- and postoperative complications were classified according to Clavien-Dindo criteria. Postoperative data were compared between groups. Risk factors associated with surgery were investigated. RESULTS: Out of 99 female patients included (average age 36.91 ± 5.36 years), 23 patients (23.2%) had transvaginal and 76 (76.8%) had suprapubic specimen extraction. The groups were comparable regarding operative time, nodule size, level of anastomosis, hospital stay and intraoperative complications. We observed no statistically significant differences in postoperative complications and rectovaginal fistula rate between the groups. Binary logistic regression analyses determined that vaginal endometriosis is an independent risk factor for postoperative complications (OR: 2.63, 95% CI [1.10-6.48], p = 0.03). CONCLUSIONS: Transvaginal specimen extraction is a safe and feasible technique in DE colorectal surgery and should be taken into consideration whenever vaginal endometriosis exists. Nevertheless, vaginal endometriosis can be an independent risk factor for postoperative complications in DE surgery.


Assuntos
Neoplasias Colorretais , Cirurgia Colorretal , Endometriose , Laparoscopia , Doenças Retais , Adulto , Neoplasias Colorretais/cirurgia , Endometriose/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Doenças Retais/etiologia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
4.
Neth Heart J ; 30(6): 328-334, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34910278

RESUMO

INTRODUCTION: Sex disparities exist in coronary artery disease (CAD) in terms of risk profile, clinical management and outcome. It is unclear if differences are also present in coronary aneurysms, a rare variant of CAD. METHODS: Patients were selected from the international Coronary Artery Aneurysm Registry (CAAR; ClinicalTrials.gov: NCT02563626), and differences between groups were analysed according to sex. The CAAR database is a prospective multicentre registry of 1565 patients with coronary aneurysms (336 females). Kaplan-Meier method was used for event-free survival analysis for death, major adverse cardiac events (MACE: composite endpoint of death, heart failure and acute coronary syndrome) and bleeding. RESULTS: Female patients were older, were more often hypertensive and less frequently smoker. They were treated conservatively more often compared to male patients and received significantly less frequently aspirin (92% vs 88%, p = 0.002) or dual antiplatelet therapy (DAPT) (67% vs 58%, p = 0.001) at discharge. Median DAPT duration was also shorter (3 vs 9 months, p = 0.001). Kaplan-Meier analysis revealed no sex differences in death, MACE or bleeding during a median follow-up duration of 37 months, although male patients did experience acute coronary syndrome (ACS) more often during follow-up (15% vs 10%, p = 0.015). CONCLUSIONS: These CAAR findings showed a comparable high-risk cardiovascular risk profile for both sexes. Female patients were treated conservatively more often and received DAPT less often at discharge, with a shorter DAPT duration. ACS was more prevalent among male patients; however, overall clinical outcome was not different between male and female patients during follow-up.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34340958

RESUMO

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG-PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.


Assuntos
COVID-19/complicações , COVID-19/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
6.
Rev Esp Med Nucl Imagen Mol ; 40(5): 299-309, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-35368611

RESUMO

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG- PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.


Assuntos
COVID-19 , COVID-19/complicações , COVID-19/diagnóstico por imagem , Fluordesoxiglucose F18 , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
7.
Rev Neurol ; 70(11): 406-412, 2020 Jun 01.
Artigo em Espanhol | MEDLINE | ID: mdl-32436207

RESUMO

INTRODUCTION: Myotonic dystrophy type 1 (MD1), or Steinert's disease, is a multisystemic disorder of autosomal dominant inheritance, whose adult variant usually presents with multidomain cognitive impairment and affects patients' functionality and quality of life. AIM: To study the four-year history of cognitive functioning in a sample of patients with the adult variant of MD1. PATIENTS AND METHODS: The neurocognitive functions of a sample of 31 patients with MD1 are evaluated, of whom 24 repeat the test administered four years ago in the Neurology Service of the Complejo Hospitalario of Navarra. Data are collected from the cognitive domains that are most related to the deficits that usually present in MD1. RESULTS: The follow-up evaluation found that the visuospatial and visuoconstructive functions and alternating attention of the patients who underwent the study were affected, as was their daily functioning reported by the family. These results are in line with those obtained four years earlier, with no significant deterioration observed between the two measurements. A higher incidence of cognitive impairment was also displayed in 2018, with some cases of progression to dementia in Steinert's disease. CONCLUSION: Neurocognitive progression in MD1 seems to respond to a progressive pattern of degeneration, linked to the functions that are most affected from the beginning of the sequelae phase and which usually correspond to the domains of working memory, alternating attention, and visuospatial and visuoconstructive abilities.


TITLE: Perfil neuropsicológico en pacientes con distrofia miotónica tipo 1: estudio de seguimiento a cuatro años.Introducción. La distrofia miotónica tipo 1 (DM1), o enfermedad de Steinert, es un trastorno multisistémico de herencia autosómica dominante, cuya variante adulta suele cursar con deterioro cognitivo multidominio y afectación de la funcionalidad y la calidad de vida de los pacientes. Objetivo. Estudiar la evolución a cuatro años del funcionamiento cognitivo de una muestra de pacientes con la variante adulta de DM1. Pacientes y métodos. Se evalúan las funciones cognitivas de una muestra de 31 pacientes con DM1, de los cuales 24 repiten la evaluación administrada hace cuatro años en el Servicio de Neurología del Complejo Hospitalario de Navarra. Se recogen datos de los dominios neurocognitivos más relacionados con los déficits de presentación habitual en la DM1. Resultados. La evaluación de seguimiento constató la afectación de las funciones visuoespaciales y visuoconstructivas y de la atención alternante de los pacientes que se sometieron al estudio, así como de su funcionamiento cotidiano informado por la familia. Estos resultados están en línea con los obtenidos cuatro años atrás, sin que se haya objetivado un deterioro significativo entre ambas mediciones. Se demuestra, además, una mayor incidencia de deterioro cognitivo en 2018, con algunos casos de evolución a demencia en la enfermedad de Steinert. Conclusión. La evolución neuropsicológica en la DM1 parece responder a un patrón progresivo, ligado a las funciones que más se afectan desde los inicios de la fase de secuelas y que suelen corresponder a los dominios de memoria de trabajo, atención alternante y habilidades visuoespaciales y visuoconstructivas.


Assuntos
Distrofia Miotônica/fisiopatologia , Distrofia Miotônica/psicologia , Adulto , Cognição , Disfunção Cognitiva/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/complicações , Testes Neuropsicológicos , Fatores de Tempo , Adulto Jovem
9.
Rev Esp Quimioter ; 33(2): 122-129, 2020 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-32149487

RESUMO

OBJECTIVE: To describe the epidemiology of Enterobacterales producing carbapenemases (EPC) in a tertiary hospital. METHODS: A retrospective observational study, all patients with a positive sample for EPC treated in hospitalization or in the Emergency Department were included, between January 1, 2014 and December 31, 2016. RESULTS: A total of 272 patients (316 samples) were included: 155 (57%) male. Mean age of 70.4 years (95% CI 68.2 -72.7). Mean Charlson index was 3.6 (95% CI 3.4-3.8). In 63.2% the acquisition was nosocomial, in 35.3% it was health-care associated (HA). 55.1% presented infection, the most frequent infection was urinary tract infection (UTI) (58.7%). The most frequent species were Klebsiella pneumoniae (62.7%) and Enterobacter cloacae (10.1%). The most frequent types of carbapenemase were OXA-48 (53.8%) and VIM (43%). The nosocomial acquisition was associated with the male gender, transplantation, immunosuppression, admission to the Intensive Care Unit (ICU) or surgical service, prior antibiotic treatment, Enterobacter, VIM, respiratory and intra-abdominal infections. The HA acquisition was associated with age and comorbidity, nursery home origin, bladder catheterization, greater number of outpatient procedures, previous hospital admission, K. pneumoniae and E. coli, OXA-48, coproduction of extended spectrum betalactamases, UTI and sepsis. CONCLUSIONS: Patients who acquire EPC in nursery homes frequently have an infection. Patients with nosocomial acqui-sition are colonized by EPC in the ICU, in relation to invasive procedures and transplantation. This population has a higher mortality due to developing respiratory infections by EPC.


Assuntos
Infecção Hospitalar/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , beta-Lactamases/metabolismo , Idoso , Infecção Hospitalar/microbiologia , Enterobacter cloacae/enzimologia , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Centros de Atenção Terciária , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia
10.
Sanid. mil ; 75(2): 113-115, abr.-jun. 2019. ilus
Artigo em Espanhol | IBECS | ID: ibc-183714

RESUMO

Descripción de la presentación clínica y la evolución de un caso de osteocondrosis del capitellum humeral (enfermedad de Panner) presentado en nuestro medio


Description of the clinical presentation and evolution of a case of osteochondrosis of the humeral capitellum (Panner's disease) presented in our environment


Assuntos
Humanos , Masculino , Criança , Hospitais Militares , Cotovelo/diagnóstico por imagem , Cotovelo/lesões , Osteocondrose/diagnóstico por imagem , Osteocondrose/terapia , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Doença de Legg-Calve-Perthes/terapia , Artroscopia/instrumentação , Artroscopia/métodos
11.
Opt Express ; 27(2): 827-840, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696163

RESUMO

The possibilities that offer the holographic optical elements for photovoltaic and "see through display" applications open new windows for holographic recording materials. In this sense, some specific characteristics are required for each particular application. Waveguides are one of the key elements for these applications. Photopolymers are one of the most competitive candidates for waveguide fabrication. In this work, we evaluate the performance of one example from each of three families of photopolymer material in fabrication of a 633nm waveguide. Firstly, polyvinyl alcohol acrylamide, PVA/AA, the second one, a nanoparticle-thiol-ene, NPC, and on the last place a penta/hexa-acrylate based polymer with dispersed nematic liquid crystal molecules, PDLC. We study the critical role of the material and in particular, spatial resolution for this application.

12.
Medicine (Madr) ; 12(55): 3245-3252, 2018 May.
Artigo em Espanhol | MEDLINE | ID: mdl-32287906

RESUMO

Recipients of the different types of transplantation are at high risk of infection. Nosocomial infections predominate in patients who have undergone haematopoietic stem cell transplantation during the early post-engraftment period (30-100 days after the infusion); the incidence of infection is higher in graft-versus-host disease. Nodular lesions can appear in the lungs due to invasive fungal infection. A diffuse pattern is usually secondary to viral infection or P. jirovecii pneumonia. After the first 100 days a moderate risk of infection by conventional and opportunistic infections persists, such as late CMV infection. Advances in surgical techniques and the use of calcineurinics have reduced mortality from infections in recipients of solid organ transplantations. Nosocomial infections are common during the first month; opportunistic infections that are dependent on cellular immunity are more common between the first and the sixth month, from the sixth month the risk lowers and community-based infections similar to those of immunocompetent patients predominate.

13.
Medicine (Madr) ; 12(56): 3291-3297, 2018 May.
Artigo em Espanhol | MEDLINE | ID: mdl-32287907

RESUMO

In general, respiratory infections are benign and self-limiting, but occasionally they can cause severe symptoms and become a major cause of mortality and morbidity, especially in the more vulnerable population groups. Flu epidemics occur annually, and there can be pandemics every few years, such as those caused by types H1N1 or H3N2. The main clinical manifestations are respiratory symptoms associated with fever, and complications such as pneumonia can arise. Nasopharyngeal swab and RT-PCR should be performed to confirm the diagnosis, which can yield results for other viruses as well. Treatment is generally symptomatic, reserving neuraminidase inhibitors for the more serious cases. The best preventive measure is annual vaccination of the population at risk. The coronavirus is also particularly relevant, due to its potential prognostic implications, and the respiratory syncytial virus and parainfluenza virus should be borne in mind in children.

14.
Transplant Proc ; 49(7): 1667-1671, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28838461

RESUMO

Patients with solid-organ transplants usually present at the emergency department with nonspecific symptoms. The physician should consider a great variety of syndromes and diseases, given the greater risk that solid-organ transplant patients carry because of immunosuppression and transplant-related conditions. Myocardial infarction caused by cardiac allograft vasculopathy must be always suspected and ruled out, even when initial symptoms do not orientate in that direction. We present a case that conjugates signs that can be present in different pathologies. It shows that fever is not always related to infection or rejection but could also appear in acute cardiac allograft vasculopathy. It emphasizes the need of a multi-disciplinary team led by a heart transplant specialist when dealing with this sort of clinical case.


Assuntos
Doença das Coronárias/etiologia , Dispneia/etiologia , Febre/etiologia , Transplante de Coração/efeitos adversos , Complicações Pós-Operatórias , Cardiomiopatias Diabéticas/cirurgia , Humanos , Terapia de Imunossupressão/efeitos adversos , Masculino , Pessoa de Meia-Idade
15.
J Am Chem Soc ; 139(17): 6120-6127, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28436654

RESUMO

The energy landscape of a supramolecular material can include different molecular packing configurations that differ in stability and function. We report here on a thermally driven crystalline order transition in the landscape of supramolecular nanostructures formed by charged chromophore amphiphiles in salt-containing aqueous solutions. An irreversible transition was observed from a metastable to a stable crystal phase within the nanostructures. In the stable crystalline phase, the molecules end up organized in a short scroll morphology at high ionic strengths and as long helical ribbons at lower salt content. This is interpreted as the result of the competition between electrostatic repulsive forces and attractive molecular interactions. Only the stable phase forms charge-transfer excitons upon exposure to visible light as indicated by absorbance and fluorescence features, second-order harmonic generation microscopy, and femtosecond transient absorbance spectroscopy. Interestingly, the supramolecular reconfiguration to the stable crystalline phase nanostructures enhances photosensitization of a proton reduction catalyst for hydrogen production.


Assuntos
Imidas/química , Perileno/química , Catálise , Cristalização , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Estrutura Molecular , Nanoestruturas/química , Tamanho da Partícula , Transição de Fase , Processos Fotoquímicos , Eletricidade Estática , Propriedades de Superfície , Termodinâmica
18.
Opt Express ; 24(2): 1559-72, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26832534

RESUMO

Photopolymers can be appealing materials for diffractive optical elements fabrication. In this paper, we present the recording of diffractive lenses in PVA/AA (Polyvinyl alcohol acrylamide) based photopolymers using a liquid crystal device as a master. In addition, we study the viability of using a diffusion model to simulate the lens formation in the material and to study the influence of the different parameters that govern the diffractive formation in photopolymers. Once we control the influence of each parameter, we can fit an optimum recording schedule to record each different diffractive optical element with the optimum focalization power.

19.
Plant Sci ; 236: 168-76, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26025530

RESUMO

The increase in grape berry ripening rates associated to climate change is a growing concern for wine makers as it rises the alcohol content of the wine. The present work studied the combined effects of elevated CO2, temperature and UV-B radiation on leaf physiology and berry ripening rates. Three doses of UV-B: 0, 5.98, 9.66 kJm(-2)d(-1), and two CO2-temperature regimes: ambient CO2-24/14 °C (day/night) (current situation) and 700 ppm CO2-28/18 °C (climate change) were imposed to grapevine fruit-bearing cuttings from fruit set to maturity under greenhouse-controlled conditions. Photosynthetic performance was always higher under climate change conditions. High levels of UV-B radiation down regulated carbon fixation rates. A transient recovery took place at veraison, through the accumulation of flavonols and the increase of antioxidant enzyme activities. Interacting effects between UV-B and CO2-temperature regimes were observed for the lipid peroxidation, which suggests that UV-B may contribute to palliate the signs of oxidative damage induced under elevated CO2-temperature. Photosynthetic and ripening rates were correlated. Thereby, the hastening effect of climate change conditions on ripening, associated to higher rates of carbon fixation, was attenuated by UV-B radiation.


Assuntos
Dióxido de Carbono/metabolismo , Mudança Climática , Raios Ultravioleta , Vitis/fisiologia , Carbono/metabolismo , Frutas/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Temperatura , Vitis/efeitos da radiação
20.
Plant Sci ; 232: 13-22, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25617319

RESUMO

This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranillo to UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed to three levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66kJm(-2)day(-1)) and two water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturity under glasshouse-controlled conditions. UV-B induced a transient decrease in net photosynthesis (Anet), actual and maximum potential efficiency of photosystem II, particularly on well watered plants. Methanol extractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activity increased with UV-B. Water deficit effected decrease in Anet and stomatal conductance, and did not change non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respiration and photorespiration being alternative ways to dissipate the excess of energy. Little interactive effects between UV-B and drought were detected on photosynthesis performance, where the impact of UV-B was overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-B and water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptive response of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatments caused additive effects on berry ripening.


Assuntos
Raios Ultravioleta , Vitis/efeitos da radiação , Clorofila/metabolismo , Dessecação , Peroxidação de Lipídeos/efeitos da radiação , Fotossíntese/efeitos da radiação , Estômatos de Plantas/efeitos da radiação , Superóxido Dismutase/metabolismo , Vitis/metabolismo , Vitis/fisiologia , Água/metabolismo
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