Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 150
Filtrar
Más filtros

Intervalo de año de publicación
1.
Physiol Plant ; 176(3): e14376, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38837784

RESUMEN

Variations in light intensity induce cytosol pH changes in photosynthetic tissues, providing a possible signal to adjust a variety of biochemical, physiological and developmental processes to the energy status of the cells. It was shown that these pH changes are partially due to the transport of protons in or out of the thylakoid lumen. However, the ion transporters in the chloroplast that transmit these pH changes to the cytosol are not known. KEA1 and KEA2 are K+/H+ antiporters in the chloroplast inner envelope that adjust stromal pH in light-to-dark transitions. We previously determined that stromal pH is higher in kea1kea2 mutant cells. In this study, we now show that KEA1 and KEA2 are required to attenuate cytosol pH variations upon sudden light intensity changes in leaf mesophyll cells, showing they are important components of the light-modulated pH signalling module. The kea1kea2 mutant mesophyll cells also have a considerably less negative membrane potential. Membrane potential is dependent on the activity of the plasma membrane proton ATPase and is regulated by secondary ion transporters, mainly potassium channels in the plasma membrane. We did not find significant differences in the activity of the plasma membrane proton pump but found a strongly increased membrane permeability to protons, especially potassium, of the double mutant plasma membranes. Our results indicate that chloroplast envelope K+/H+ antiporters not only affect chloroplast pH but also have a strong impact on cellular ion homeostasis and energization of the plasma membrane.


Asunto(s)
Arabidopsis , Cloroplastos , Citosol , Antiportadores de Potasio-Hidrógeno , Concentración de Iones de Hidrógeno , Citosol/metabolismo , Cloroplastos/metabolismo , Antiportadores de Potasio-Hidrógeno/metabolismo , Antiportadores de Potasio-Hidrógeno/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/efectos de la radiación , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Luz , Potenciales de la Membrana , Potasio/metabolismo , Células del Mesófilo/metabolismo , Mutación/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/efectos de la radiación
2.
Int J Mol Sci ; 25(8)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38673963

RESUMEN

Accurate etiologic diagnosis provides an appropriate secondary prevention and better prognosis in ischemic stroke (IS) patients; still, 45% of IS are cryptogenic, urging us to enhance diagnostic precision. We have studied the transcriptomic content of plasma extracellular vesicles (EVs) (n = 21) to identify potential biomarkers of IS etiologies. The proteins encoded by the selected genes were measured in the sera of IS patients (n = 114) and in hypertensive patients with (n = 78) and without atrial fibrillation (AF) (n = 20). IGFBP-2, the most promising candidate, was studied using immunohistochemistry in the IS thrombi (n = 23) and atrium of AF patients (n = 13). In vitro, the IGFBP-2 blockade was analyzed using thromboelastometry and endothelial cell cultures. We identified 745 differentially expressed genes among EVs of cardioembolic, atherothrombotic, and ESUS groups. From these, IGFBP-2 (cutoff > 247.6 ng/mL) emerged as a potential circulating biomarker of embolic IS [OR = 8.70 (1.84-41.13) p = 0.003], which was increased in patients with AF vs. controls (p < 0.001) and was augmented in cardioembolic vs. atherothrombotic thrombi (p < 0.01). Ex vivo, the blockage of IGFBP-2 reduced clot firmness (p < 0.01) and lysis time (p < 0.001) and in vitro, diminished endothelial permeability (p < 0.05) and transmigration (p = 0.06). IGFBP-2 could be a biomarker of embolic IS and a new therapeutic target involved in clot formation and endothelial dysfunction.


Asunto(s)
Biomarcadores , Vesículas Extracelulares , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina , Accidente Cerebrovascular Isquémico , Trombosis , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Biomarcadores/sangre , Masculino , Femenino , Anciano , Trombosis/metabolismo , Trombosis/etiología , Trombosis/sangre , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/sangre , Accidente Cerebrovascular Isquémico/genética , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Persona de Mediana Edad , Perfilación de la Expresión Génica , Transcriptoma , Fibrilación Atrial/metabolismo , Fibrilación Atrial/genética , Fibrilación Atrial/complicaciones , Fibrilación Atrial/sangre
3.
J Oncol Pharm Pract ; 29(4): 975-979, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36131486

RESUMEN

PURPOSE: To report the efficacy and safety of 5-fluorouracil as the second line of treatment for two cases of conjunctival intraepithelial neoplasia refractive to topical interferon alpha-2b. CASE REPORT: In the first case, a 77-year-old woman was evaluated because of a fleshy vascularized lesion in the temporal conjunctiva on her right eye with leukoplakia of the corneal epithelium from 10- to 5-o'clock limbus. In the second case, an 81-year-old man, a nodular lesion in the temporal conjunctiva on his RE, with corneal adjacent opalescence, one millimeter in extent, was observed. Both patients were initially treated with excisional surgery, the samples being reported as conjunctival intraepithelial neoplasia with high-grade dysplasia. Co-adjuvant treatment with topical interferon alpha-2b 1 mIU/mL was indicated 4 times/day uninterruptedly. In the first case, there was no response despite 8 months of treatment, while in the second, the corneal lesion progressed in an arboriform pattern after 4 months of topical chemotherapy. MANAGEMENT & OUTCOME: In the absence of efficacy, the treatment was then changed to topical 5-fluorouracil (1%), 4 times/day for 7 days with a time-lapse of 21 days off, which constitutes a course. Two and four courses of treatment with 5-fluorouracil 1% were completed in both cases in the absence of important side effects. After the first course, both patients showed complete remission of the lesions. No clinical signs of relapse were noted after 1 year of follow-up. DISCUSSION: The treatment with 5-fluorouracil is a good option as the second line of treatment for conjunctival intraepithelial neoplasia who are low-responders to interferon alpha-2b, with fewer side effects than other currently available alternatives.


Asunto(s)
Antineoplásicos , Neoplasias de la Conjuntiva , Humanos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Interferón alfa-2/uso terapéutico , Interferón-alfa/efectos adversos , Neoplasias de la Conjuntiva/tratamiento farmacológico , Neoplasias de la Conjuntiva/patología , Fluorouracilo/efectos adversos , Administración Tópica , Resultado del Tratamiento , Proteínas Recombinantes/uso terapéutico
4.
Eur J Nutr ; 61(3): 1445-1455, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34842966

RESUMEN

PURPOSE: Inflammation could play a key role in tissue damage and bone metabolism. The modified dietary inflammatory score (M-DIS) is a validated tool to estimate the inflammatory potential of the diet. In the present study, we evaluate the associations between the M-DIS and bone mineral density (BMD) in a senior Mediterranean population with overweight/obesity and metabolic syndrome. METHODS: Baseline cross-sectional association between the M-DIS and bone mineral density was assessed in 1134 participants of the multicenter PREDIMED-Plus trial (aged 55-75 with overweight/obesity and metabolic syndrome). BMD was measured using Dual-energy X-ray Absorptiometry scans and participants answered a food frequency questionnaire to determine the M-DIS. BMD was categorized as low BMD when T score was equal or lower than -1 and normal BMD in another case. Associations between BMD and M-DIS were evaluated by using linear and logistic regressions adjusted by other co-variates. RESULTS: Participants in the top tertile of the M-DIS had a lower BMD at total femur [ß (95% CI) - 0.02 (- 0.04, - 0.01)], trochanter areas [ß (95% CI) - 0.03 (- 0.05, - 0.01)] and lumbar spine area [ß (95% CI) - 0.03 (- 0.07, 0.01)] (but in the last case, measures were less precise and hence not statistically significant) compared to those in the lower M-DIS tertile. Multiple logistic regression analyses showed that the odds of the total femur and femoral trochanter osteopenia/osteoporosis were higher in participants in the top tertile compared to those in the lowest tertile of M-DIS [OR (95% CI) 1.71 (1.12, 2.64), P for trend 0.015; 2.02 (1.29, 3.21), P for trend 0.002, respectively]. CONCLUSION: A high pro-inflammatory diet, measured by the M-DIS, is associated with lower BMD in a senior Mediterranean population with metabolic syndrome.


Asunto(s)
Densidad Ósea , Osteoporosis , Absorciometría de Fotón , Anciano , Estudios Transversales , Dieta , Humanos , Persona de Mediana Edad , Osteoporosis/epidemiología
5.
Int J Mol Sci ; 23(14)2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35887350

RESUMEN

Photosensitive supramolecular systems have garnered attention due to their potential to catalyze highly specific tasks through structural changes triggered by a light stimulus. The tunability of their chemical structure and charge transfer properties provides opportunities for designing and developing smart materials for multidisciplinary applications. This review focuses on the approaches reported in the literature for tailoring properties of the photosensitive supramolecular systems, including MOFs, MOPs, and HOFs. We discuss relevant aspects regarding their chemical structure, action mechanisms, design principles, applications, and future perspectives.

6.
Aten Primaria ; 54 Suppl 1: 102471, 2022 10.
Artículo en Español | MEDLINE | ID: mdl-36435585

RESUMEN

In the 2022 PAPPS update we present those specific preventive activities for women's health, except those related to cancer prevention (which are included in another document) and those aspects related to differential gender morbidity, a cross-cutting aspect for all working groups. Contraception is an essential preventive activity, considering basic the right to decide both the number of children and the time to have them. We must inform about the possible contraceptive methods, guaranteeing the monitoring of their safety, efficacy and effectiveness (tables are included on changing from one method to another to preserve contraceptive protection). We must inform about emergency contraception and propose it in the event of unprotected intercourse. All this will be done through opportunistic screening without requiring screening for thrombophilia or dyslipidemia, but for arterial hypertension. Pregnancy is an important life experience and the family doctor should not remain oblivious. We must be competent both in the preconception consultation (recommending the intake of folic acid, avoiding exposure to occupational and environmental risks, screening for certain pathologies and assessing the intake of drugs not indicated during pregnancy) and in the monitoring of pregnancy. Whether or not we monitor the pregnancy, we must not disregard its control, taking advantage of this period to promote healthy lifestyles and participating in the intercurrent processes that may occur. Menopause in general and osteoporosis in particular exemplify the strategy of medicalization of vital processes that has been followed from different instances and organizations. In our update we address the prevention and treatment of symptoms secondary to estrogen deprivation. We also propose the prevention of osteoporosis, including carrying out densitometry based on the risk of fracture in the next 10 years, and therefore densitometric screening is not recommended in women under 60 years of age. In risk assessment we recommend the use of the frax tool or better, the calibration of the risk of hip fracture with prevalence data from our setting. We linked the indication for treatment with the Z-Score (bone mineral density compared with women of the same age), as it is a condition associated with aging.


Asunto(s)
Fracturas de Cadera , Osteoporosis , Niño , Femenino , Humanos , Osteoporosis/tratamiento farmacológico , Densidad Ósea , Posmenopausia , Medición de Riesgo/métodos
7.
Technol Forecast Soc Change ; 174: 121301, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34703063

RESUMEN

Business activities within the tourism industry are especially suffering from the consequences of the COVID19 pandemic. Those countries whose economy depends largely on tourism will experience a troublesome situation for years to come. Their return to a normal situation will be conditioned by the competitiveness of their tourism sector. The study begins by pinpointing the countries that have been more hardly stricken by the pandemic and in which tourism accounts for a greater share of the GDP. A comparative analysis of the competitiveness of these countries with that of world-leading countries will be carried out so as to conclude which will face the recovery period in a more vulnerable situation. The measurement of tourism competitiveness will be supported by the creation of a synthetic indicator based on the P2 distance method. A group of 13 countries has been identified as the most vulnerable, and it is advisable to act urgently in the following areas: the promotion of cultural elements and the historical and artistic heritage, the protection of natural areas, the availability of information and communication technologies, the international openness of the destination, and the availability of transportation infrastructures and tourist services.

8.
Rev Esp Enferm Dig ; 113(4): 303-304, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33228366

RESUMEN

Paroxysmal nocturnal hemoglobinuria (PNH) is a type of hemolytic anemia acquired by the PIG-A gene mutation. This causes a deficiency of a complement regulatory protein, CD59, which results in hemolysis, hemoglobinuria and thrombosis (due to the release of procoagulant factors). Budd-Chiari syndrome is characteristic in these patients and has classically been considered as a contraindication for liver transplantation (LT) due to post-transplant recurrence. Since the approval of eculizumab for the treatment of PHN, disease control is possible and therefore the post-transplant recurrence of thrombotic phenomena involving the liver is avoided.


Asunto(s)
Síndrome de Budd-Chiari , Hemoglobinuria Paroxística , Trasplante de Hígado , Trombosis , Hemoglobinuria Paroxística/tratamiento farmacológico , Hemólisis , Humanos , Trombosis/etiología
9.
Rev Esp Enferm Dig ; 113(4): 272-275, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33222476

RESUMEN

INTRODUCTION: caustic ingestion in children is rare but has potentially serious consequences. AIM: to analyze the clinical and endoscopic features and the type of caustic ingested in our population. METHODS: the upper endoscopies performed in this setting, as well as the characteristics of patients and caustics, were analyzed from 2010 to 2018. RESULTS: fifty-one endoscopies were performed (48 cases of witnessed intake or high suspicion and three with a low suspicion) in patients with a mean age of 2.55 years. Alkali ingestion was more frequent (88.2 %) and 56.9 % of the endoscopies were normal, which was more frequent among those who ingested bleach (72 %). Alkali tended to produce more esophageal injuries (31.1 %) and acids tended to produce esophageal (20 %) and esophageal-gastric injuries (20 %). Four patients developed esophageal stenosis during follow-up. DISCUSSION: even though more than half of the studies were normal, endoscopy is important in the diagnosis and prognosis of these patients.


Asunto(s)
Quemaduras Químicas , Cáusticos , Estenosis Esofágica , Quemaduras Químicas/diagnóstico por imagen , Quemaduras Químicas/epidemiología , Quemaduras Químicas/etiología , Cáusticos/toxicidad , Niño , Preescolar , Ingestión de Alimentos , Endoscopía , Estenosis Esofágica/inducido químicamente , Estenosis Esofágica/diagnóstico por imagen , Humanos
10.
Plant Physiol ; 181(3): 1277-1294, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31451552

RESUMEN

Potassium (K+) is a key monovalent cation necessary for multiple aspects of cell growth and survival. In plants, this cation also plays a key role in the control of stomatal movement. KAT1 and its homolog KAT2 are the main inward rectifying channels present in guard cells, mediating K+ influx into these cells, resulting in stomatal opening. To gain further insight into the regulation of these channels, we performed a split-ubiquitin protein-protein interaction screen searching for KAT1 interactors in Arabidopsis (Arabidopsis thaliana). We characterized one of these candidates, BCL2-ASSOCIATED ATHANOGENE4 (BAG4), in detail using biochemical and genetic approaches to confirm this interaction and its effect on KAT1 activity. We show that BAG4 improves KAT1-mediated K+ transport in two heterologous systems and provide evidence that in plants, BAG4 interacts with KAT1 and favors the arrival of KAT1 at the plasma membrane. Importantly, lines lacking or overexpressing the BAG4 gene show altered KAT1 plasma membrane accumulation and alterations in stomatal movement. Our data allowed us to identify a KAT1 regulator and define a potential target for the plant BAG family. The identification of physiologically relevant regulators of K+ channels will aid in the design of approaches that may impact drought tolerance and pathogen susceptibility.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiología , Estomas de Plantas/metabolismo , Canales de Potasio de Rectificación Interna/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Membrana Celular/metabolismo , Técnicas de Placa-Clamp , Estomas de Plantas/fisiología , Potasio/metabolismo , Canales de Potasio de Rectificación Interna/genética , Canales de Potasio con Entrada de Voltaje/genética , Canales de Potasio con Entrada de Voltaje/metabolismo
11.
Aten Primaria ; 52 Suppl 2: 125-148, 2020 11.
Artículo en Español | MEDLINE | ID: mdl-33388112

RESUMEN

A review is presented of the scientific evidence on preventive activities in women's care in relation to pregnancy follow-up, preventive activities in the planning and follow-up of contraceptive methods, preventive activities in menopause, and the prevention of osteoporotic fractures.


Asunto(s)
Anticoncepción , Salud de la Mujer , Femenino , Humanos , Embarazo
13.
BMC Cancer ; 18(1): 781, 2018 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-30068302

RESUMEN

BACKGROUND: The incidence of breast cancer has increased since the 1970s. Despite favorable trends in prognosis, the role of changes in clinical practice and the introduction of screening remain controversial. We examined breast cancer trends to shed light on their determinants. METHODS: Data were obtained for 8502 new cases of breast cancer in women between 1985 and 2012 from a population-based cancer registry in Granada (southern Spain), and for 2470 breast cancer deaths registered by the Andalusian Institute of Statistics. Joinpoint regression analyses of incidence and mortality rates were obtained. Observed and net survival rates were calculated for 1, 3 and 5 years. The results are reported here for overall survival and survival stratified by age group and tumor stage. RESULTS: Overall, age-adjusted (European Standard Population) incidence rates increased from 48.0 cases × 100,000 women in 1985-1989 to 83.4 in 2008-2012, with an annual percentage change (APC) of 2.5% (95%CI, 2.1-2.9) for 1985-2012. The greatest increase was in women younger than 40 years (APC 3.5, 95%CI, 2.4-4.8). For 2000-2012 the incidence trend increased only for stage I tumors (APC 3.8, 95%CI, 1.9-5.8). Overall age-adjusted breast cancer mortality decreased (APC - 1, 95%CI, - 1.4 - - 0.5), as did mortality in the 50-69 year age group (APC - 1.3, 95%CI, - 2.2 - - 0.4). Age-standardized net survival increased from 67.5% at 5 years in 1985-1989 to 83.7% in 2010-2012. All age groups younger than 70 years showed a similar evolution. Five-year net survival rates were 96.6% for patients with tumors diagnosed in stage I, 88.2% for stage II, 62.5% for stage III and 23.3% for stage IV. CONCLUSIONS: Breast cancer incidence is increasing - a reflection of the evolution of risk factors and increasing diagnostic pressure. After screening was introduced, the incidence of stage I tumors increased, with no decrease in the incidence of more advanced stages. Reductions were seen for overall mortality and mortality in the 50-69 year age group, but no changes were found after screening implementation. Survival trends have evolved favorably except for the 70-84 year age group and for metastatic tumors.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Sistema de Registros , España/epidemiología , Análisis de Supervivencia
14.
Int J Mol Sci ; 19(5)2018 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-29751549

RESUMEN

Bicarbonate plays a fundamental role in the cell pH status in all organisms. In autotrophs, HCO3− may further contribute to carbon concentration mechanisms (CCM). This is especially relevant in the CO2-poor habitats of cyanobacteria, aquatic microalgae, and macrophytes. Photosynthesis of terrestrial plants can also benefit from CCM as evidenced by the evolution of C4 and Crassulacean Acid Metabolism (CAM). The presence of HCO3− in all organisms leads to more questions regarding the mechanisms of uptake and membrane transport in these different biological systems. This review aims to provide an overview of the transport and metabolic processes related to HCO3− in microalgae, macroalgae, seagrasses, and terrestrial plants. HCO3− transport in cyanobacteria and human cells is much better documented and is included for comparison. We further comment on the metabolic roles of HCO3− in plants by focusing on the diversity and functions of carbonic anhydrases and PEP carboxylases as well as on the signaling role of CO2/HCO3− in stomatal guard cells. Plant responses to excess soil HCO3− is briefly addressed. In conclusion, there are still considerable gaps in our knowledge of HCO3− uptake and transport in plants that hamper the development of breeding strategies for both more efficient CCM and better HCO3− tolerance in crop plants.


Asunto(s)
Bicarbonatos/metabolismo , Plantas/metabolismo , Animales , Dióxido de Carbono/metabolismo , Anhidrasas Carbónicas/metabolismo , Humanos
15.
Clin Chem Lab Med ; 55(11): 1715-1721, 2017 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-28282290

RESUMEN

BACKGROUND: The presence of preanalytical mistakes (PM) in samples from primary care centres (PCC) is a widely studied topic. Different correcting strategies have been proposed, with variable success. We planned a series of multidisciplinary sessions for clinical update, with the aim to decrease PM rates in samples from PCC. METHODS: The incidence of PM in samples from PCC processed at the laboratories of University Hospital Virgen de la Victoria (LAB1) and University Hospital Juan Ramon Jimenez (LAB2) was assessed during two time periods (October to November 2013 and January to May 2014). Clinical update sessions were conducted between periods (2014). Differences in PM rates between observation periods were evaluated. RESULTS: With respect to 2014, we observed a significant reduction of PM rates in blood samples processed at LAB1 during 2015, whereas those in LAB2 were slightly increased. The most common PMs were haemolysed sample at LAB1 and missed sample at LAB2. CONCLUSIONS: Although the presence of PM remains slightly high, there was a significant reduction after the clinical update sessions in LAB1, where the most frequent PM was haemolysed sample. In contrast, the PM rates were slightly increased at LAB2, and the main source was missed sample. This might be explained, at least in part, by different problems associated with sample transportation, and by the delay in transferring acquired knowledge into clinical practice. Implementation of regular programme of update sessions and improvements in sample transportation might help to reduce the PM presence in our area.


Asunto(s)
Errores Diagnósticos , Laboratorios de Hospital/normas , Manejo de Especímenes/normas , Hemólisis , Humanos , Atención Primaria de Salud
16.
Sensors (Basel) ; 17(5)2017 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-28471387

RESUMEN

The aim of the Smart and Networking Underwater Robots in Cooperation Meshes (SWARMs) project is to make autonomous underwater vehicles (AUVs), remote operated vehicles (ROVs) and unmanned surface vehicles (USVs) more accessible and useful. To achieve cooperation and communication between different AUVs, these must be able to exchange messages, so an efficient and reliable communication network is necessary for SWARMs. In order to provide an efficient and reliable communication network for mission execution, one of the important and necessary issues is the topology control of the network of AUVs that are cooperating underwater. However, due to the specific properties of an underwater AUV cooperation network, such as the high mobility of AUVs, large transmission delays, low bandwidth, etc., the traditional topology control algorithms primarily designed for terrestrial wireless sensor networks cannot be used directly in the underwater environment. Moreover, these algorithms, in which the nodes adjust their transmission power once the current transmission power does not equal an optimal one, are costly in an underwater cooperating AUV network. Considering these facts, in this paper, we propose a Probabilistic Topology Control (PTC) algorithm for an underwater cooperating AUV network. In PTC, when the transmission power of an AUV is not equal to the optimal transmission power, then whether the transmission power needs to be adjusted or not will be determined based on the AUV's parameters. Each AUV determines their own transmission power adjustment probability based on the parameter deviations. The larger the deviation, the higher the transmission power adjustment probability is, and vice versa. For evaluating the performance of PTC, we combine the PTC algorithm with the Fuzzy logic Topology Control (FTC) algorithm and compare the performance of these two algorithms. The simulation results have demonstrated that the PTC is efficient at reducing the transmission power adjustment ratio while improving the network performance.

17.
Sensors (Basel) ; 17(5)2017 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-28531135

RESUMEN

In this work, we focus on key topics related to underwater Simultaneous Localization and Mapping (SLAM) applications. Moreover, a detailed review of major studies in the literature and our proposed solutions for addressing the problem are presented. The main goal of this paper is the enhancement of the accuracy and robustness of the SLAM-based navigation problem for underwater robotics with low computational costs. Therefore, we present a new method called AEKF-SLAM that employs an Augmented Extended Kalman Filter (AEKF)-based SLAM algorithm. The AEKF-based SLAM approach stores the robot poses and map landmarks in a single state vector, while estimating the state parameters via a recursive and iterative estimation-update process. Hereby, the prediction and update state (which exist as well in the conventional EKF) are complemented by a newly proposed augmentation stage. Applied to underwater robot navigation, the AEKF-SLAM has been compared with the classic and popular FastSLAM 2.0 algorithm. Concerning the dense loop mapping and line mapping experiments, it shows much better performances in map management with respect to landmark addition and removal, which avoid the long-term accumulation of errors and clutters in the created map. Additionally, the underwater robot achieves more precise and efficient self-localization and a mapping of the surrounding landmarks with much lower processing times. Altogether, the presented AEKF-SLAM method achieves reliably map revisiting, and consistent map upgrading on loop closure.

18.
J Phys Ther Sci ; 29(8): 1399-1404, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28878471

RESUMEN

[Purpose] The purpose of this study was to analyse the intraday test-retest reliability of stabilometric measurements on the Centre of Pressure (CoP) in persons with Multiple Sclerosis. [Subjects and Methods] The measurements were taken with the subject standing on the force platform with both feet together, in four different conditions: eyes open and closed whilst standing on both a rigid surface and then on foam. The measurements were taken on three occasions with intervals of 20 minutes between them. 18 persons with confirmed Multiple Sclerosis (MS), (aged 44.4 ± 13.3 years and 3.5 ± 1.5 EDSS) participated in the study. Relative reliability was measured using the intraclass correlation coefficient (ICC) and the 95% confidence interval (95% CI); and the absolute reliability using the coefficient of variation (CV) and standard error of measurement (SEM). [Results] The measurements of the CoP in all of the variables in each of the four conditions, showed a reliability of good to excellent (ICC=0.69-0.92) in the intraday test-retest. The variables which showed greatest consistency with repetition were X Speed, Y Speed and Side Length. [Conclusion] Given the results it would seem that the best variables for monitoring postural control in persons with MS are Speed on X and Y along with Side Length.

19.
Photosynth Res ; 127(3): 295-305, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26275764

RESUMEN

Mechanisms of inorganic carbon assimilation were investigated in the four deep-water kelps inhabiting sea bottoms at the Strait of Gibraltar; these species are distributed at different depths (Saccorhiza polysiches at shallower waters, followed by Laminaria ochroleuca, then Phyllariopsis brevipes and, at the deepest bottoms, Phyllariopsis purpurascens). To elucidate the capacity to use HCO3(-) as a source of inorganic carbon for photosynthesis in the kelps, different experimental approaches were used. Specifically, we measured the irradiance-saturated gross photosynthetic rate versus pH at a constant dissolved inorganic carbon (DIC) concentration of 2 mM, the irradiance-saturated apparent photosynthesis (APS) rate versus DIC, the total and the extracellular carbonic anhydrase (CAext), the observed and the theoretical photosynthetic rates supported by the spontaneous dehydration of HCO3(-) to CO2, and the δ(13)C signature in tissues of the algae. While S. polyschides and L. ochroleuca showed photosynthetic activity at pH 9.5 (around 1.0 µmol O2 m(-2) s(-1)), the activity was close to zero in both species of Phyllariopsis. The APS versus DIC was almost saturated for the DIC values of natural seawater (2 mM) in S. polyschides and L. ochroleuca, but the relationship was linear in P. brevipes and P. purpurascens. The four species showed total and CAext activities but the inhibition of the CAext originated the observed photosynthetic rates at pH 8.0 to be similar to the theoretical rates that could be supported by the spontaneous dehydration of HCO3(-). The isotopic (13)C signatures ranged from -17.40 ± 1.81 to -21.11 ± 1.73 ‰ in the four species. Additionally, the δ(13)C signature was also measured in the deep-water Laminaria rodriguezii growing at 60-80 m, showing even a more negative value of -26.49 ± 1.25 ‰. All these results suggest that the four kelps can use HCO3(-) as external carbon source for photosynthesis mainly by the action of external CAext, but they also suggest that the species inhabiting shallower waters show a higher capacity than the smaller kelps living in deeper waters. In fact, the photosynthesis in the two Phyllariopsis species could be accomplished by the spontaneous dehydration of HCO3(-) to CO2. These differences in the capacity to use HCO3(-) in photosynthesis among species could be important considering the increasing levels of atmospheric CO2 predicted for the near future.


Asunto(s)
Carbono/metabolismo , Compuestos Inorgánicos/metabolismo , Kelp/metabolismo , Fotosíntesis , Agua de Mar/química , Anhidrasas Carbónicas/metabolismo , Gibraltar , Concentración de Iones de Hidrógeno , Kelp/efectos de la radiación , Luz , Oxígeno/metabolismo , Fotosíntesis/efectos de la radiación
20.
Int J Gynecol Cancer ; 26(9): 1722-1726, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27518143

RESUMEN

OBJECTIVE: The purpose of this study was to compare the long-term safety, disease-free survival, and recurrence rate of total laparoscopic hysterectomy using uterine manipulator and abdominal hysterectomy in the surgical treatment in early-stage endometrial cancer. STUDY DESIGN: This was a cohort study of 147 patients with clinical endometrial cancer (laparoscopic surgery group, 77 women; laparotomy group, 70 women). Data were evaluated and analyzed by intention-to-treat principle, and survival data of stage I endometrial cancer (129 patients; 66 from laparoscopic surgery group and 60 from laparotomy group) were estimated by using the Kaplan-Meier curves. RESULTS: After a follow-up period of 60 months for both laparoscopic surgery and laparotomy groups, no significant difference in the cumulative recurrence rates (7.4% and 13.1%, P = 0.091) and overall survival (97.1% and 95.1%, P = 0.592) was detected between both groups of stage I endometrial cancer. Conversion to laparotomy occurred in 10.4% (8/77) of the laparoscopic procedures. Laparoscopic hysterectomy was associated with less use of pain medication (P = 0.001) and a shorter hospital stay (P < 0.001), but the procedure took longer than laparotomic hysterectomy (P < 0.001). The proportion of patients with intraoperative and long-term complications was not significantly different between both groups. The use of uterine manipulators did not have increased recurrence rate in patients treated with laparoscopic approach. CONCLUSIONS: The laparoscopic surgery approach to early-stage endometrial cancer using uterine manipulators is as safe and effective as the laparotomic approach.


Asunto(s)
Carcinoma/cirugía , Neoplasias Endometriales/cirugía , Histerectomía/instrumentación , Recurrencia Local de Neoplasia/epidemiología , Anciano , Carcinoma/mortalidad , Estudios de Cohortes , Supervivencia sin Enfermedad , Neoplasias Endometriales/mortalidad , Femenino , Humanos , Histerectomía/métodos , Persona de Mediana Edad , España/epidemiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA