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1.
Ned Tijdschr Geneeskd ; 1652022 01 12.
Artículo en Holandés | MEDLINE | ID: mdl-35129887

RESUMEN

There's a lot of attention for gluten-free diets on social media. Doctors get many questions about gluten sensitivity or possible wheat allergy. With some basic knowledge, it's easier to give answers to these questions and to prevent unnecessary and sometimes harmful diets. This article gives basic information about cereals, gluten, grasses and their crossreactivity. We give an overview about the differences between celiac disease, gluten sensitivity and IgE-mediated wheat allergy. We also describe diagnostics, treatment and natural history of coeliakie, gluten sensitivity and wheat or cereal allergy.


Asunto(s)
Enfermedad Celíaca , Hipersensibilidad al Trigo , Enfermedad Celíaca/diagnóstico , Niño , Dieta Sin Gluten , Grano Comestible , Glútenes/efectos adversos , Humanos , Hipersensibilidad al Trigo/terapia
2.
Clin Mol Allergy ; 19(1): 14, 2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34372856

RESUMEN

BACKGROUND: Specific IgE (sIgE) against the peanut component Arachis hypogaea (Ara h) 2 has been shown to be the most important allergen to discriminate between peanut allergy and peanut tolerance. Several studies determined sIgE cut off values for Ara h 2, determined by singleplex measurements. However, cut off values for Ara h 2 from multiplex arrays are less well defined. The aim of this study was to evaluate the correlation between Ara h 2 sIgE determined by singleplex versus multiplex measurements and to assess the diagnostic value of the different peanut components included in Immuno Solid-phase Allergen Chip (ISAC) multiplex analysis in children with a suspected peanut allergy. METHODS: In this retrospective study we analyzed Ara h 2 sIgE values with singleplex Fluorescence Enzyme Immunoassay (FEIA, ImmunoCap) and multiplex microarray (ISAC) measurements in 117 children with a suspected peanut allergy. Also, other peanut components measured by ISAC were analyzed. Double blinded placebo controlled oral food challenges were used as golden standard. RESULTS: Among all studied peanut components FEIA Ara h 2 sIgE showed the highest area under the curve (AUC, 0.922), followed by ISAC Ara h 6 and Ara h 2 sIgE with AUCs of respectively 0.906 and 0.902. Best cut off values to diagnose peanut allergy were 4.40 kU/l for FEIA Ara h 2 sIgE and, 7.43 ISU and 8.13 ISU for respectively Ara h 2 and Ara h 6 sIgE in ISAC microarray. Ara h 2 sIgE determined in FEIA and ISAC showed a good correlation (r = 0.88; p < 0.01). CONCLUSION: Ara h 6 and Ara h 2 sIgE in multiplex ISAC are both good predictors of clinical peanut allergy in Dutch children, and their performance is comparable to the use of Ara h 2 in singleplex FEIA. The simultaneous measurement of different peanut components using ISAC is an advantage and clinically useful to detect peanut allergic children that are Ara h 2 negative but sensitized to other peanut proteins such as Ara h 6.

3.
Acta Chir Belg ; 120(4): 231-237, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30895917

RESUMEN

Objective: To determine the effect of primary conservative treatment without revascularization in patients with proven aortoiliac occlusive disease (AIOD) presenting with intermittent claudication (IC).Background: The initial treatment of IC should focus on supervised exercise therapy (SET) and pharmacotherapy. Nowadays, primary endovascular revascularization (EVR) has become increasingly popular in patients with all types of AIOD. But in daily practice, EVR is often performed without initially extensive exercise.Method: This is a single centre retrospective study from December 2012 to September 2017. Primary outcomes were maximum walking distance (MWD) and patient satisfaction. Secondary outcomes were revascularization rate and mortality.Results: Twenty-four patients were included. Mean age was 64 years (SD: 9). Mean follow-up was 28 months (SD: 17). Nineteen patients (80%) had SET. In 18 (75%) patients, the MWD was improved compared to the initial situation. In five (21%) patients, the MWD stayed the same. The MWD of one (4%) patient decreased. Overall satisfaction rate was 87%. Three patients (13%) were not satisfied with the conservative treatment and eventually got an EVR. There was no disease related death.Conclusions: Conservative treatment, especially with SET, has acceptable subjective symptom outcomes in selected patients with AIOD. It could be a good alternative treatment for certain patients with AIOD and IC.


Asunto(s)
Aorta Abdominal , Arteriopatías Oclusivas/terapia , Tratamiento Conservador/métodos , Arteria Ilíaca , Anciano , Angiografía , Arteriopatías Oclusivas/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Claudicación Intermitente/diagnóstico , Claudicación Intermitente/terapia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonografía
4.
Ann Vasc Surg ; 60: 270-278.e2, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31077770

RESUMEN

BACKGROUND: Delirium in patients with critical limb ischemia (CLI) is associated with increased mortality. The main goal of this study was to investigate the association between delirium and mortality in patients undergoing major lower limb amputation for CLI. In addition, other risk factors associated with mortality were analyzed. METHODS: An observational cohort study was conducted including all patients aged ≥70 years with CLI undergoing a major lower limb amputation between January 2014 and July 2017. Delirium was scored using the Delirium Observation Screening Score in combination with the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Risk factors for mortality were analyzed by calculating hazard ratios using a Cox proportional hazards model. RESULTS: In total, 95 patients were included; of which, 29 (31%) patients developed a delirium during admission. Delirium was not associated with an increased risk of mortality (hazard ratio [HR] = 0.84; 95 % confidence interval [CI]: 0.51-1.73; P = 0.84). Variables independently associated with an increased risk of mortality were age (HR 1.1; 95% CI 1.0-1.1), cardiac history (HR 3.3; 95% CI 1.8-6.1), current smoking (HR 2.9; 95% CI 1.6-5.5), preoperative anemia (HR 2.8; 95% CI 1.1-7.2), and living in a nursing home (HR 2.2; 95% CI 1.1-4.4). CONCLUSION: Delirium was not associated with an increased mortality risk in elderly patients with CLI undergoing a major lower limb amputation. Factors related to an increased mortality risk were age, cardiac history, current smoking, preoperative anemia, and living in a nursing home.


Asunto(s)
Amputación Quirúrgica/mortalidad , Delirio/mortalidad , Isquemia/cirugía , Extremidad Inferior/irrigación sanguínea , Enfermedad Arterial Periférica/cirugía , Factores de Edad , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica/efectos adversos , Enfermedad Crítica , Delirio/diagnóstico , Delirio/psicología , Femenino , Humanos , Incidencia , Isquemia/diagnóstico por imagen , Isquemia/mortalidad , Isquemia/fisiopatología , Masculino , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/mortalidad , Enfermedad Arterial Periférica/fisiopatología , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
5.
Physiol Res ; 66(4): 615-620, 2017 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-28406701

RESUMEN

Recently, we have established a model of severe stepwise normovolemic hemodilution to a hematocrit of 10 % in rats employing three different colloidal volume replacement solutions (Voluven, Volulyte and Gelafundin) that are routinely used in clinical practice at present. We did not see severe dilutional acidosis as to be expected, but a decline in urinary pH. We here looked on further mechanisms of renal acid excretion during normovolemic hemodilution. Bicarbonate, which had been removed during normovolemic hemodilution, was calculated with the help of the Henderson-Hasselbalch equation. The urinary amount of ammonium as well as phosphate was determined in residual probes. The absolute amount of free protons in urine was obtained from the pH of the respective samples. The amount of protons generated during normovolemic hemodilution was approximately 0.6 mmol. During experimental time (5.5 h), distinct urinary ammonium excretion occurred (Voluven 0.52 mmol, Volulyte 0.39 mmol and Gelafundin 0.77 mmol). Proton excretion via the phosphate buffer constituted 0.04 mmol in every experimental group. Excretion of free protons was in the range of 10(-6) mmol. The present data prove that the prompt rise in urinary ammonium excretion is also valid for acute metabolic acidosis originating from severe normovolemic hemodilution.


Asunto(s)
Acidosis/orina , Compuestos de Amonio/orina , Hemodilución/efectos adversos , Modelos Animales , Índice de Severidad de la Enfermedad , Acidosis/fisiopatología , Animales , Hemodilución/métodos , Masculino , Ratas , Ratas Wistar
6.
Clin Transl Allergy ; 7: 8, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28321292

RESUMEN

BACKGROUND: Cashew nut, pistachio nut and mango belong to the Anacardiaceae family and are botanically related. Therefore, cashew nut sensitised children are frequently advised to eliminate cashew nuts and pistachio nuts from their diet. The 'Improvement of Diagnostic mEthods for ALlergy assessment (IDEAL trial number NTR3572) study showed that cashew nut sensitised children were co-sensitised to pistachio nut in 98% of cases and to mango in 21% of cases. The aim of this follow-up study to IDEAL is to assess the clinical relevance of co-sensitisation to pistachio nut and mango in cashew nut sensitised children. METHODS: Children were recruited from the study: 'Improvement of Diagnostic mEthods for ALlergy assessment (IDEAL trial number NTR3572). Inclusion criterion for the IDEAL study was sensitization to cashew nut as demonstrated by either SPT or sIgE, and a clinical history of reactions to cashew nuts or no previous (known) exposure. Sensitized children who were tolerant to cashew nuts were excluded. Inclusion criterion for this IDEAL follow-up study was co-sensitization to pistachio nut, regardless the result of the DBPCFC with cashew nut. In this follow-up study a double-blind placebo-controlled food challenge with pistachio nut and an open food challenge with mango were performed. RESULTS: Twenty-nine children (mean age of 11.6 years, 62% male) were included. Pistachio nut sensitisation was clinically relevant in only 34% of cashew-sensitised children and only 31% of cashew challenge positive children. None of the children was challenge positive to mango. CONCLUSION: Although co-sensitisation between cashew nut and pistachio nut was observed in 98%, pistachio nut sensitisation was only clinically relevant in 34% of the children. Therefore, a challenge test with pistachio nut is recommended in children with cashew nut and pistachio nut sensitisation. Trial registration The study was registered in the Dutch trial register (registration number 3572) on 10 August 2012 (retrospectively registered).

7.
Support Care Cancer ; 25(3): 729-737, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27787681

RESUMEN

PURPOSE: Although vaginal dilator use after combined pelvic radiation therapy and brachytherapy (RT/BT) is recommended to prevent vaginal shortening and stenosis, women fail to use them and experience sexual problems. A nurse-led sexual rehabilitation intervention targeting sexual recovery and vaginal dilatation was developed. Its feasibility was investigated during a prospective, longitudinal, observational pilot study. METHODS: Four oncology nurses were specifically trained to conduct the intervention. Gynecologic cancer patients treated with RT/BT were assessed using (i) questionnaires on frequency of dilator use (monthly), sexual functioning, and sexual distress (at baseline and 1, 6, and 12 months) and psychological and relational distress (at 1, 6, and 12 months); (ii) semi-structured interviews (between 6 and 12 months); and (iii) consultation recordings (a random selection of 21 % of all consults). RESULTS: Twenty participants were 26-71 years old (mean = 40). Eight participants discontinued participation after 3 to 9 months. At 6 months after RT, 14 out of 16 (88 %), and at 12 months 9 out of 12 (75 %), participants dilated regularly, either by having sexual intercourse or by using dilators. Sexual functioning improved between 1 and 6 months after RT, with further improvement at 12 months. Most participants reported that the intervention was helpful and the nurses reported having sufficient expertise and counseling skills. CONCLUSIONS: According to the pilot results, the intervention was feasible and promising for sexual rehabilitation and regular dilator use after RT. Its (cost-)effectiveness will be investigated in a randomized controlled trial.


Asunto(s)
Neoplasias de los Genitales Femeninos/enfermería , Neoplasias de los Genitales Femeninos/rehabilitación , Rol de la Enfermera , Traumatismos por Radiación/enfermería , Traumatismos por Radiación/rehabilitación , Conducta Sexual/fisiología , Anciano , Braquiterapia/efectos adversos , Constricción Patológica/etiología , Constricción Patológica/enfermería , Constricción Patológica/rehabilitación , Femenino , Neoplasias de los Genitales Femeninos/fisiopatología , Neoplasias de los Genitales Femeninos/radioterapia , Humanos , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Traumatismos por Radiación/etiología , Traumatismos por Radiación/fisiopatología , Encuestas y Cuestionarios , Vagina/patología , Vagina/fisiopatología , Vagina/efectos de la radiación
8.
J Matern Fetal Neonatal Med ; 30(21): 2626-2632, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27834108

RESUMEN

OBJECTIVE: Neonatal early-onset infection is a life-threatening disease, requiring early diagnosis and treatment. Newborns at risk are identified by a combination of risk factors, clinical signs of infection and laboratory parameters such as white blood cell count and C-reactive protein (CRP). This method is labor-intensive, time consuming and has a variable reproducibility. New reliable diagnostic markers are needed to identify neonatal infection. This study presents additional leukocyte differential parameters produced by the automated flow cytometry and processing software using CytoDiff™ reagent (Beckman Coulter) in newborns suspected for early-onset infection. METHODS: An analytic prospective observational case-control study was performed in which 185 newborns were included and retrospectively allocated into two groups, "infection likely" and "infection unlikely". Leukocyte parameters of the CytoDiff™ technique were compared with microscopic slide differentiation and routine tests. RESULTS: We showed significant lower numbers of monocytes, CD16(-) monocytes and lymphocytes (including T+/NK-lymphocytes) in neonates suspected for early-onset infection using CytoDiff™ technique. The manual counting did not demonstrate changes with respect to the number of monocytes in these neonates. CONCLUSIONS: The automated routine CytoDiff™ leukocyte differential provides an interesting additional diagnostic tool, next to routine laboratory diagnostics, in the diagnosis of neonatal early-onset infection.


Asunto(s)
Citometría de Flujo/métodos , Infecciones/diagnóstico , Humanos , Recién Nacido , Infecciones/sangre , Recuento de Linfocitos , Estudios Prospectivos , Estudios Retrospectivos
9.
Clin Exp Allergy ; 47(1): 113-120, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27513566

RESUMEN

BACKGROUND: The double-blind, placebo-controlled food challenge test (DBPCFC) is the gold standard in cashew nut allergy. This test is costly, time consuming and not without side effects. Analysis of IgE reactivity to cashew nut components may reduce the need for food challenge tests. METHODS: In a prospective and multicentre study, children with suspected cashew nut allergy underwent a DBPCFC with cashew nut. Specific IgE to cashew nut and to the components Ana o 1, 2 and 3 were determined. A skin prick test (SPT) with cashew nut extract was performed. The association between the outcome of the food challenge test and specific IgE to Ana o 1, 2 and 3 was assessed with logistic regression analyses, unadjusted and adjusted for other diagnostic variables. Discriminative ability was quantified with a concordance index (c). RESULTS: A total of 173 children (103 boys, 60%) with a median age of 9 years were included. About 79% had a positive challenge test outcome. A steep rise in the risk of a positive challenge was observed for specific IgE to each individual component Ana o 1, 2 and 3 with estimated risks up to approximately 100%. Median values of Ana o 1, 2, 3 were 1.29 kU/l (range 0-100 kU/l), 4.77 kU/l (range 0-100 kU/l) and 8.33 kU/l (range 0-100 kU/l) respectively and varied significantly (p < 0.001). Specific IgE to Ana o 1, 2 and 3 was better distinguished between cashew-allergic and tolerant children (c = 0.87, 0.85 and 0.89, respectively) than specific IgE to cashew nut or SPT (c = 0.76 and 0.83, respectively). CONCLUSION: The major cashew nut allergens Ana o 1, 2 and 3 are each individually predictive for the outcome of food challenge tests in cashew-allergic children.


Asunto(s)
Alérgenos/inmunología , Anacardium/efectos adversos , Inmunoglobulina E/inmunología , Hipersensibilidad a la Nuez/diagnóstico , Hipersensibilidad a la Nuez/inmunología , Nueces/efectos adversos , Antígenos de Plantas/inmunología , Biomarcadores , Niño , Preescolar , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Proteínas de Plantas/inmunología , Estudios Prospectivos , Pruebas Cutáneas
10.
PLoS One ; 11(9): e0163258, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27662620

RESUMEN

Arabidopsis thaliana is the most widely used model organism for research in plant biology. While significant advances in understanding plant growth and development have been made by focusing on the molecular genetics of Arabidopsis, extracting and understanding the functional framework of metabolism is challenging, both from a technical perspective due to losses and modification during extraction of metabolites from the leaves, and from the biological perspective, due to random variation obscuring how well the function is performed. The purpose of this work is to establish the in vivo metabolic profile directly from the Arabidopsis thaliana leaves without metabolite extraction, to reduce the complexity of the results by multivariate analysis, and to unravel the mitigation of cellular complexity by predominant functional periodicity. To achieve this, we use the circadian cycle that strongly influences metabolic and physiological processes and exerts control over the photosynthetic machinery. High resolution-magic angle spinning nuclear magnetic resonance (HR-MAS NMR) was applied to obtain the metabolic profile directly from intact Arabidopsis leaves. Combining one- and two-dimensional 1H HR-MAS NMR allowed the identification of several metabolites including sugars and amino acids in intact leaves. Multivariate analysis on HR-MAS NMR spectra of leaves throughout the circadian cycle revealed modules of primary metabolites with significant and consistent variations of their molecular components at different time points of the circadian cycle. Since robust photosynthetic performance in plants relies on the functional periodicity of the circadian rhythm, our results show that HR-MAS NMR promises to be an important non-invasive method that can be used for metabolomics of the Arabidopsis thaliana mutants with altered physiology and photosynthetic efficiency.

11.
Pediatr Allergy Immunol ; 27(8): 812-817, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27495003

RESUMEN

BACKGROUND: Previous studies showed that health-related quality of life (HRQL) significantly improved after the food challenge, with greater improvements in HRQL after a negative outcome than after a positive outcome. It is currently unknown whether this also occurs in patients undergoing DBPCFCs with cashew nut in the context of a clinical trial. METHODS: Quality of life was studied in children enrolled in a cashew nut study using Food Allergy Quality of Life Questionnaires (FAQLQs). Children, teenagers and parents of the children completed the questionnaires before the challenge test and 6 months after the DBPCFC with cashew nut. The difference in the change in HRQL between the children with a positive and negative DBPCFC outcome was studied by Mann-Whitney U-test. RESULTS: In total, 112 children (67 boys, median age of 9 years) were included. The children, teenagers and parents of the children completed 143 sets of questionnaires in total. There were no significant differences in baseline total and domain scores compared to the follow-up scores in the FAQLQ-CF, FAQLQ-TF and FAQLQ-PF. In children, the delta FAIM score in the negative DBPCFC tested group was significantly better than the delta FAIM score in the positive challenged group (p = 0.026). There were no significant differences in the changes in the scores of the FAQLQ-CF and FAQLQ-PF in the children with a positive challenge outcome, compared to the children with a negative challenge result. However, there was a significant difference in the change in score between the latter groups in the domain 'accidental exposure' of the FAQLQ-TF (p = 0.049). CONCLUSION: This study showed no difference in the change in HRQL scores after a DBPCFC with cashew nut in children participating in a clinical trial. The utility of HRQL as an outcome for clinical trials in food allergy may be limited if participant baseline HRQL is relatively unimpaired.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad a la Nuez/diagnóstico , Calidad de Vida , Adolescente , Anacardium/inmunología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Inmunización , Masculino , Padres , Encuestas y Cuestionarios
14.
J Photochem Photobiol B ; 152(Pt B): 261-71, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26282679

RESUMEN

Both photosystem I and photosystem II are considerably similar in molecular architecture but they operate at very different electrochemical potentials. The origin of the different redox properties of these RCs is not yet clear. In recent years, insight was gained into the electronic structure of photosynthetic cofactors through the application of photochemically induced dynamic nuclear polarization (photo-CIDNP) with magic-angle spinning NMR (MAS NMR). Non-Boltzmann populated nuclear spin states of the radical pair lead to strongly enhanced signal intensities that allow one to observe the solid-state photo-CIDNP effect from both photosystem I and II from isolated reaction center of spinach (Spinacia oleracea) and duckweed (Spirodela oligorrhiza) and from the intact cells of the cyanobacterium Synechocystis by (13)C and (15)N MAS NMR. This review provides an overview on the photo-CIDNP MAS NMR studies performed on PSI and PSII that provide important ingredients toward reconstruction of the electronic structures of the donors in PSI and PSII.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Oxígeno/metabolismo , Fotosíntesis , Transporte de Electrón , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo
15.
Br J Cancer ; 113(4): 645-52, 2015 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-26171939

RESUMEN

BACKGROUND: Isolated limb perfusion with TNF-alpha and melphalan (TM-ILP) is a highly effective treatment for locally advanced tumours of the extremities. Previous research suggests an almost immediate disintegration of the blood supply of the tumour. The aim of the present study was to verify this hypothesis using non-invasive measurements of microvascular perfusion and tissue oxygenation. METHODS: A total of 11 patients were included in the study. TM-ILP was performed under mildly hyperthermic conditions (39 °C) in the extremities via proximal vascular access. Capillary-venous microvascular blood flow, haemoglobin level (Hb) and oxygen saturation (SO2) were determined using laser Doppler and white-light spectroscopy, respectively, before TM-ILP and at 30 min, 4 h, 1 day, 4 days, 1 week, 2 weeks and 6 weeks after TM-ILP from tumour and healthy muscle tissues. RESULTS: Blood flow and Hb were mostly higher, whereas SO2 was lower, in tumour tissue compared with muscle tissue. In both tumour and muscle tissues, blood flow significantly increased immediately after TM-ILP and remained elevated for at least 2 weeks, followed by a return to the initial values 6 weeks after the procedure. CONCLUSION: No signs were found of early destruction of the tumour vasculature. The observations suggest that an inflammatory reaction is one of the key elements of TM-ILP.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Extremidades/patología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neovascularización Patológica/tratamiento farmacológico , Flujo Sanguíneo Regional/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Alquilantes/administración & dosificación , Quimioterapia del Cáncer por Perfusión Regional/métodos , Hemoglobinas/metabolismo , Humanos , Hipertermia Inducida/métodos , Melfalán/administración & dosificación , Persona de Mediana Edad , Músculos/efectos de los fármacos , Músculos/metabolismo , Neoplasias/irrigación sanguínea , Neovascularización Patológica/patología , Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/administración & dosificación
16.
Interface Focus ; 5(3): 20150014, 2015 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-26052428

RESUMEN

This contribution discusses why we should consider developing artificial photosynthesis with the tandem approach followed by the Dutch BioSolar Cells consortium, a current operational paradigm for a global artificial photosynthesis project. We weigh the advantages and disadvantages of a tandem converter against other approaches, including biomass. Owing to the low density of solar energy per unit area, artificial photosynthetic systems must operate at high efficiency to minimize the land (or sea) area required. In particular, tandem converters are a much better option than biomass for densely populated countries and use two photons per electron extracted from water as the raw material into chemical conversion to hydrogen, or carbon-based fuel when CO2 is also used. For the average total light sum of 40 mol m(-2) d(-1) for The Netherlands, the upper limits are many tons of hydrogen or carbon-based fuel per hectare per year. A principal challenge is to forge materials for quantitative conversion of photons to chemical products within the physical limitation of an internal potential of ca 2.9 V. When going from electric charge in the tandem to hydrogen and back to electricity, only the energy equivalent to 1.23 V can be stored in the fuel and regained. A critical step is then to learn from nature how to use the remaining difference of ca 1.7 V effectively by triple use of one overpotential for preventing recombination, kinetic stabilization of catalytic intermediates and finally generating targeted heat for the release of oxygen. Probably the only way to achieve this is by using bioinspired responsive matrices that have quantum-classical pathways for a coherent conversion of photons to fuels, similar to what has been achieved by natural selection in evolution. In appendix A for the expert, we derive a propagator that describes how catalytic reactions can proceed coherently by a convergence of time scales of quantum electron dynamics and classical nuclear dynamics. We propose that synergy gains by such processes form a basis for further progress towards high efficiency and yield for a global project on artificial photosynthesis. Finally, we look at artificial photosynthesis research in The Netherlands and use this as an example of how an interdisciplinary approach is beneficial to artificial photosynthesis research. We conclude with some of the potential societal consequences of a large-scale roll out of artificial photosynthesis.

18.
J Microencapsul ; 31(8): 738-45, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24963954

RESUMEN

Perfluorodecalin (PFD) is an established artificial oxygen carrier due to its physical capability to solve the respiratory gases oxygen and carbon dioxide. PFD-filled poly(n-butyl-cyanoacrylate) (PACA) nanocapsules are already discussed as effective artificial oxygen carriers, and their principal suitability for intravenous administration had been shown. To further elucidate their action in vivo, it is imperative to characterise their preclinical safety and particularly their biodistribution. For these purposes, intravital fluorescence microscopy would display an attractive technique in order to monitor the PACA nanocapsules in vivo, but unfortunately, it is impossible to stain the PACA nanocapsules with a fluorescent dye fulfilling special criteria required for in vivo microscopy. In order to develop such a dye, a long-chained fluorinated thiol was used to modify a BODIPY derivative that is a highly fluorescent organic compound belonging to the difluoro-boraindacene family, as well as to functionalise mesoscopic systems, such as CdSe/ZnS-quantum dots and gold nanoparticles. Furthermore, a functionalisation of porphyrin derivatives was investigated by placing divalent ions in the centre of these systems. Due to the high solubility of all synthesised dyes in PFD, it should be possible to stain PFD-filled particles in general. However, only the functionalised BODIPY derivative was suitable for in vivo monitoring of the PFD-filled PACA nanocapsules.


Asunto(s)
Compuestos de Boro , Colorantes Fluorescentes , Fluorocarburos , Puntos Cuánticos/química , Animales , Compuestos de Boro/química , Compuestos de Boro/farmacocinética , Compuestos de Boro/farmacología , Enbucrilato/química , Enbucrilato/farmacocinética , Enbucrilato/farmacología , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacocinética , Colorantes Fluorescentes/farmacología , Fluorocarburos/química , Fluorocarburos/farmacocinética , Fluorocarburos/farmacología , Masculino , Microscopía Fluorescente , Ratas , Ratas Wistar
19.
J Consult Clin Psychol ; 81(6): 1127-1136, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24060195

RESUMEN

OBJECTIVE: Vaginismus is commonly described as a persistent difficulty in allowing vaginal entry of a penis or other "objects" (e.g., tampons, fingers, speculum). Lifelong vaginismus is diagnosed when a woman has never been able to have intercourse. The aim of this study was to investigate the efficacy of therapist-aided exposure for lifelong vaginismus. METHOD: Seventy women and their partners were randomly allocated to exposure or a waiting-list control period of 3 months. The main outcome measure (intercourse ability) was assessed daily during 12 weeks. Secondary outcome measures were complaints about vaginismus, coital pain, coital fear, sexual distress, and sexual functioning. The exposure treatment consisted of a maximum of three 2-hr sessions during 1 week at a university hospital. Each participant performed vaginal penetration exercises herself, in the presence of her partner and a female therapist. Two follow-up sessions were scheduled over a 5-week period. RESULTS: Thirty-one out of 35 (89%; 95% CI [72%, 96%]) participants reported having had sexual intercourse at posttreatment compared with 4 out of 35 (11%; 95% CI [4%, 28%]) participants in the control condition. In most of the successfully treated women (90%), intercourse was possible within the first 2 weeks of treatment. Moreover, treatment resulted in clinical improvement regarding other symptoms related to vaginismus, coital fear, coital pain, and sexual distress. No treatment effects were found regarding other aspects of sexual functioning in women or their partners. CONCLUSIONS: This study provides evidence of the efficacy of therapist-aided exposure therapy for women with lifelong vaginismus.


Asunto(s)
Terapia Implosiva/métodos , Relaciones Profesional-Paciente , Vaginismo/psicología , Vaginismo/terapia , Adulto , Coito/psicología , Cultura , Miedo , Femenino , Estudios de Seguimiento , Humanos , Apoyo Social , Adulto Joven
20.
Eur J Surg Oncol ; 39(9): 945-50, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23850089

RESUMEN

AIM: Video assisted thoracic surgery (VATS) is an important tool in the field of thoracic pathology both for therapeutic and diagnostic purposes. The standard technique for localisation of non-visible or non-palpable lung lesions is the use of image guided insertion of a guide-wire. However, this method is associated with complications such as pneumothorax, bleeding and wire-dislocation. The aim of this study was to investigate the feasibility of using of iodine seeds (I-125) as a marker of lung lesions during VATS. METHODS: 28 consecutive patients with parenchymal lung lesions had I-125 seed localisation performed prior to VATS. After seed placement all patients underwent VATS with wedge resection. RESULTS: During surgery all lesions could be identified and radically resected. In six (21.4%) patients the seed was not placed optimally but none of these cases were associated with seed dislocation after placement. In four and in 5 patients the placement of the I-125 seed was complicated by a haematoma and pneumothorax respectively. However, in all of these patients a wait-and-see policy would have been justified. In one patient a conversion to a thoracotomy was necessary due to seed displacement. CONCLUSION: In patients with parenchymal lung lesions undergoing VATS and wedge resection I-125 seed localisation is a feasible technique. Complication rates are comparable to standard guide-wire localisation. Although I-125 seeds can be positioned under CT-guidance an optimal placement is of utmost importance for VATS wedge resection. Further research is needed to investigate the possible advantages of this technique.


Asunto(s)
Neoplasias Pulmonares/cirugía , Nódulos Pulmonares Múltiples/cirugía , Neumonectomía/métodos , Nódulo Pulmonar Solitario/cirugía , Cirugía Torácica Asistida por Video/métodos , Adulto , Anciano , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Humanos , Radioisótopos de Yodo , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Nódulos Pulmonares Múltiples/diagnóstico , Radiografía Intervencional , Nódulo Pulmonar Solitario/diagnóstico , Cirugía Torácica Asistida por Video/instrumentación
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