Cost-Effectiveness of a Telemedicine Optometric-Based Assessment for Screening Diabetic Retinopathy in a Country with a Universal Public Health System.

Objective: To determine the cost-effectiveness of a new telemedicine optometric-based screening program of diabetic retinopathy (DR) compared with traditional models' assessments in a universal European public health system. Methods: A new teleophthalmology program for DR based on the assessment of retinographies (3-field Joslin Vision Network by a certified optometrist and a reading center [IOBA-RC]) was designed. This program was first conducted in a rural area 40 km from the referral hospital (Medina de Rioseco, Valladolid, Spain). The cost-effectiveness was compared with telemedicine based on evaluations by primary care physicians and general ophthalmologists, and to face-to-face examinations conducted by ophthalmologists. A decision tree model was developed to simulate the cost-effectiveness of both models, considering public and private costs. The effectiveness was measured in terms of quality of life. Results: A total of 261 patients with type 2 diabetes were included (42 had significant DR and required specific surveillance by the RC; 219 were undiagnosed). The sensitivity and specificity of the detection of DR were 100% and 74.1%, respectively. The telemedicine-based DR optometric screening model demonstrated similar utility to models based on physicians and general ophthalmologists and traditional face-to-face evaluations (0.845) at a lower cost/patient (€51.23, €71.65, and €86.46, respectively). Conclusions: The telemedicine-based optometric screening program for DR in a RC demonstrated cost savings even in a developed country with a universal health care system. These results support the expansion of this kind of teleophthalmology program not only for screening but also for the follow-up of diabetic patients.

Transcultural adaptation to Spain of the CDPQOL questionnaire specific for coeliac children.

This study aimed to translate, cross-culturally adapt, and validate the CDPQOL questionnaire, a coeliac disease (CD)-specific paediatric health-related quality of life (HRQoL) instrument (CDPQOL), in Spanish children with CD. The CDPQOL questionnaire has two versions for children aged 8-12 and 13-18. Translation and linguistic validation were performed following an international consensus process. Internal consistency was calculated using Cronbach's alpha and McDonald's omega coefficients, and convergent validity was assessed with average variance extracted (AVE). Confirmatory factor analysis (CFA) and exploratory factor analysis (EFA), when necessary, were carried out to assess the construct validity. A total of 235 children were included. In the 8-12 age group, a change in the distribution of items to a new structure of three dimensions (negative emotions, food feelings and social interaction) was required. In this new model, CFA supported the fit of the model (χ2/gl = 1.79, RMSEA = 0.077 (IC 95% 0.05-0.100), CFI = 0.969, TLI 0.960, SRMR = 0.081) and Cronbach's alpha and McDonald's omega coefficients were > 0.7 in all three dimensions. In the 13-18 age group, CFA showed that all fit indexes were acceptable (χ2/gl = 1.702, RMSEA = 0.102 (IC 95% 0.077-0.127), p < 0.001, CFI = 0.956, TLI = 0.947, SRMR = 0.103) and Cronbach's alpha and McDonald's omega coefficients were > 0.7 in all three dimensions, except for uncertainty dimension. Conclusions: The Spanish version of the CDPQOL questionnaire is a useful instrument to assess quality of life in coeliac children whose native language was Spanish spoken in Spain, with changes in item distribution in the younger age group questionnaire. What is Known: • The first specific questionnaire for coeliac children, Dutch Coeliac Disease Questionnaire (CDDUX), which focuses on diet, was translated into Spanish and validated allowing to evaluate the HRQoL of Spanish coeliac children. • Spanish Children and parents feel the disease had no substantial negative impacts on patient HRQoL using this questionnaire, similar to that observed with other countries. What is New: • The age specific for CD children (CDPQOL) was elaborated in the USA and focuses on other aspects not evaluated by CDDUX such as emotional and social issues related to living with CD. • The CDPQOL was translated into Spanish and validated allowing it to be used to assess Spanish coeliac children's QoL.

Ammonium affects the wet chemical network of HCN: feedback between prebiotic chemistry and materials science.

Prebiotic chemistry one-pot reactions, such as HCN-derived polymerizations, have been used as stimulating starting points for the generation of new multifunctional materials due to the simplicity of the processes, use of water as solvent, and moderate thermal conditions. Slight experimental variations in this special kind of polymerization tune the final properties of the products. Thus, herein, the influence of NH4Cl on the polymerization kinetics of cyanide under hydrothermal conditions and on the macrostructures and properties of this complex system is explored. The kinetics of the process is consistent with an autocatalytic model, but important variations in the polymerization reaction are observed according to a simple empirical model based on a Hill equation. The differences in the kinetic behaviour against NH4Cl were also revealed when the structural, morphological, thermal, electronic and magnetic properties of the synthesized cyanide polymers were compared, and these properties were evaluated by elemental analysis, FTIR, XPS, UV-vis, and ESR spectroscopies, X-ray diffraction, SEM and thermoanalytical techniques. As a result, this hydrothermal prebiotic polymerization is not only pH dependent, as previously thought, but also ammonium subservient. From this result, a hypothetical reaction mechanism was proposed, which involves the active participation of ammonium cations via formamidine and serves as a remarkable point against previous reports. The results discussed here expand the knowledge on HCN wet chemistry, offer an extended view of the relevant parameters during the simulation of hydrothermal scenarios and describe the production of promising paramagnetic and semiconducting materials inspired by prebiotic chemistry.

Multivariate Analysis Applied to Microwave-Driven Cyanide Polymerization: A Statistical View of a Complex System.

For the first time, chemometrics was applied to the recently reported microwave-driven cyanide polymerization. Fast, easy, robust, low-cost, and green-solvent processes are characteristic of these types of reactions. These economic and environmental benefits, originally inspired by the constraints imposed by plausible prebiotic synthetic conditions, have taken advantage of the development of a new generation of HCN-derived multifunctional materials. HCN-derived polymers present tunable properties by temperature and reaction time. However, the apparently random behavior observed in the evolution of cyanide polymerizations, assisted by microwave radiation over time at different temperatures, leads us to study this highly complex system using multivariate analytical tools to have a proper view of the system. Two components are sufficient to explain between 84 and 98% of the total variance in the data in all principal component analyses. In addition, two components explain more than 91% of the total variance in the data in the case of principal component analysis for categorical data. These consistent statistical results indicate that microwave-driven polymerization is a more robust process than conventional thermal syntheses but also that plausible prebiotic chemistry in alkaline subaerial environments could be more complex than in the aerial part of these systems, presenting a clear example of the "messy chemistry" approach of interest in the research about the origins of life. In addition, the methodology discussed herein could be useful for the data analysis of extraterrestrial samples and for the design of soft materials, in a feedback view between prebiotic chemistry and materials science.

Prebiotic synthesis of noncanonical nucleobases under plausible alkaline hydrothermal conditions.

Herein, the potential of alkaline hydrothermal environments for the synthesis of possible ancestral pre-RNA nucleobases using cyanide as a primary source of carbon and nitrogen is described. Water cyanide polymerizations were assisted by microwave radiation to obtain high temperature and a relatively high pressure (MWR, 180 °C, 15 bar) and were also carried out using a conventional thermal system (CTS, 80 °C, 1 bar) to simulate subaerial and aerial hydrothermal conditions, respectively, on the early Earth. For these syntheses, the initial concentration of cyanide and the diffusion effects were studied. In addition, it is well known that hydrolysis conditions are directly related to the amount and diversity of organic molecules released from cyanide polymers. Thus, as a first step, we studied the effect of several hydrolysis procedures, generally used in prebiotic chemistry, on some of the potential pre-RNA nucleobases of interest, together with some of their isomers and/or deamination products, also presumably formed in these complex reactions. The results show that the alkaline hydrothermal scenarios with a relatively constant pH are good geological scenarios for the generation of noncanonical nucleobases using cyanide as a prebiotic precursor.

MALT lymphoma and eosinophilic oesophagitis: incidental finding- review of possible factors influencing the aetiopathogenesis of eosinophilic oesophagitis.

An 11-year-old boy with a history of atopy and allergic rhinitis under treatment with sublingual immunotherapy was referred following several episodes of food impaction. Diagnosis of eosinophilic oesophagitis, chronic gastritis and gastric mucosa-associated lymphoid tissue (MALT) lymphoma associated to Helicobacter pylori were confirmed. Results of the extension study were negative and the lymphoma was resolved with eradicating treatment for H. pylori No improvement was observed in the oesophagitis after the withdrawal of immunotherapy and treatment with high proton pump inhibitor doses or following the omission of several foods to which subclinical sensitisation was confirmed. Oesophagitis was finally resolved by removing cow's milk protein. After 10 years, neither eosinophilic oesophagitis nor MALT lymphoma was observed.Gastric MALT lymphoma associated to H. pylori is a rare disorder in children. Although coexisting H. pylori infection is common in patients with eosinophilic oesophagitis, the association of gastric MALT lymphoma with eosinophilic oesophagitis has not been reported before.

An XPS study of HCN-derived films on pyrite surfaces: a prebiotic chemistry standpoint towards the development of protective coatings.

Traditionally, the effect of mineral surfaces on increasing molecular complexity has been considered a major issue in studies about the origin of life. In contrast, herein, the effects of organic films derived from cyanide over an important prebiotic mineral, pyrite, are considered. An XPS spectroscopy study was carried out to understand the surface chemistry of the HCN-derived polymer/pyrite system. As a result, the simulation of a plausible prebiotic alkaline hydrothermal environment led to the identification of an NH4CN-based film with protective corrosion properties that immediately prevented the oxidation of the highly reactive pyrite surface. In addition, the effect of coating with antioxidant properties was preserved over a relatively long time, and the polymeric film was very stable under ambient conditions. These results increase the great potential of HCN polymers for development as a cheap and easily produced new class of multifunctional polymeric materials that also show promising and attractive insights into prebiotic chemistry.

Tuning the Morphology in the Nanoscale of NH4CN Polymers Synthesized by Microwave Radiation: A Comparative Study.

A systematic study is presented to explore the NH4CN polymerization induced by microwave (MW) radiation, keeping in mind the recent growing interest in these polymers in material science. Thus, a first approach through two series, varying the reaction times and the temperatures between 130 and 205 °C, was conducted. As a relevant outcome, using particular reaction conditions, polymer conversions similar to those obtained by means of conventional thermal methods were achieved, with the advantage of a very significant reduction of the reaction times. The structural properties of the end products were evaluated using compositional data, spectroscopic measurements, simultaneous thermal analysis (STA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). As a result, based on the principal component analysis (PCA) from the main experimental results collected, practically only the crystallographic features and the morphologies in the nanoscale were affected by the MW-driven polymerization conditions with respect to those obtained by classical syntheses. Therefore, MW radiation allows us to tune the morphology, size and shape of the particles from the bidimensional C=N networks which are characteristic of the NH4CN polymers by an easy, fast, low-cost and green-solvent production. These new insights make these macromolecular systems attractive for exploration in current soft-matter science.

A dual perspective on the microwave-assisted synthesis of HCN polymers towards the chemical evolution and design of functional materials.

In this paper, the first study on NH4CN polymerization induced by microwave radiation is described, where a singular kinetic behaviour, especially when this reaction is conducted in the absence of air, is found. As a result, a complex conjugated N-heterocyclic polymer system is obtained, whose properties are very different, and even improved according to morphological features, characterized by their X-ray diffraction patterns and scanning electron microscopy analysis, with respect to those produced under conventional thermal treatment. In addition, a wide variety of relevant bioorganics have been identified, such as amino acids, nucleobases, co-factors, etc., from the synthetized NH4CN polymers. These particular families of polymers are of high interest in the fields of astrobiology and prebiotic chemistry and, more recently, in the development of smart multifunctional materials. From an astrobiological perspective, microwave-driven syntheses may simulate hydrothermal environments, which are considered ideal niches for increasing organic molecular complexity, and eventually as scenarios for an origin of life. From an industrial point of view and for potential applications, a microwave irradiation process leads to a notable decrease in the reaction times, and tune the properties of these new series macromolecular systems. The characteristics found for these materials encourage the development of further systematic research on this alternative HCN polymerization.