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1.
Nephrol Dial Transplant ; 38(3): 778-786, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36083994

RESUMO

BACKGROUND: Post-transplant prediabetes (PreDM) and diabetes (PTDM) are common and have an impact on cardiovascular events. We sought to investigate the pathogenesis and best approach for prediction. METHODS: We prospectively studied 115 waitlisted patients from a single center without manifest diabetes. An oral glucose tolerance test (OGTT) was performed yearly until transplantation and 12 months later. Insulin secretion, insulin sensitivity (IS) and disposition index (DI) were derived from the OGTT. RESULTS: PreDM and PTDM were observed in 27% and 28.6% of patients, respectively. Pretransplant age, body mass index (BMI), 120 min glucose, IS, DI, and prediabetes or undiagnosed diabetes were significantly associated with these alterations. In multivariate analysis, pretransplant age [odds ratio (OR) 1.5; 95% confidence interval (CI) 1.04-2.1], BMI (OR 1.16; 95% CI 1.04-1.3) and cumulative steroids (OR 1.5; 95% CI 1.02-2.2) were predictors of PreDM or PTDM. Receiver operating characteristic curve analysis showed that pretransplant BMI and 120 min glucose had the highest area under the curve (0.72; 95% CI 0.62-0.8; and 0.69; 95% CI 0.59-0.79, respectively). The highest discrimination cut-off for BMI (≥28.5 kg/m2) and 120 min glucose (≥123.5 mg/dL) yielded a similar number needed to diagnose (2.5). CONCLUSIONS: PreDM or PTDM develops in waitlisted patients with an ineffective insulin secretion and BMI shows a similar diagnostic capacity to OGTT. Pretransplant interventions may reduce post-transplant glucose alterations.


Assuntos
Diabetes Mellitus , Resistência à Insulina , Transplante de Rim , Estado Pré-Diabético , Humanos , Transplante de Rim/efeitos adversos , Estudos Prospectivos , Estado Pré-Diabético/complicações , Glucose , Glicemia/metabolismo , Diabetes Mellitus/etiologia
2.
Phys Chem Chem Phys ; 24(44): 27441-27448, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36341868

RESUMO

We envisioned a new approach for achieving triplet-triplet annihilation-assisted photon upconversion based on the rational design of a heavy-atom-free, all-organic and photoactivatable triplet-triplet synergistic multichromophoric molecular assembly. This single molecular architecture is easily built by covalently anchoring triplet-annihilator units (pyrenes) to a triplet-photosensitizer moiety (BODIPY), to improve the effectiveness and probability of the required triplet-triplet energy transfer and the ulterior triplet-triplet annihilation. This unprecedented design takes advantage of the high synthetic accessibility and chemical versatility of the COO-BODIPY scaffold. The laser-induced photophysical characterization, assisted by computational simulations (quantum mechanics calculations at single molecular level and molecular dynamics in a solvent cage), identifies the key factors to finely control the intersystem crossing and reverse intersystem crossing probability, pivotal to improve energy transfer efficiency between the involved triplet states. Likewise, theoretical simulations highlight the relevance of the new photoactivable chromophoric design to promote intra- and inter-molecular triplet-triplet annihilation towards enhanced photon upconversion, yielding noticeable fluorescence from pyrene units even under unfavorable conditions (aerated solutions of low concentration at room temperature). The understanding of the complex dynamics sustained by this single molecular architecture could approach the next generation of chemically accessible and low-cost materials enabling fluorescence by photon upconversion mediated by triplet-triplet annihilation.


Assuntos
Fótons , Pirenos , Transferência de Energia
3.
Phys Chem Chem Phys ; 20(14): 9289-9297, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29564427

RESUMO

Cementation is a widespread technique to immobilize nuclear waste due to the low leachability of cementitious materials. The capacity of calcium silicate hydrate (C-S-H), the main component of cement, to retain radionuclide Cs has been empirically studied at the macroscale, yet the specific molecular scale mechanisms that govern the retention have not been determined. In this work, we employed molecular dynamics simulations to investigate the adsorption and diffusivity of Cs into a C-S-H gel nanopore. From the simulations, it was possible to distinguish three types of Cs adsorption configurations on the C-S-H: an inner-sphere surface site where Cs is strongly bound, an outer-sphere surface site where Cs is loosely bound, and Cs free in the nanopore. For each configuration, we determined the sorption energy, and the diffusion coefficients, up to two orders of magnitude lower than in bulk water due to the effect of nanoconfinement in the worst case scenario. It has also proved that Cs cannot displace the intrinsic Ca from the C-S-H surface, and we calculated the binding strength and the residence time of the cations in the surface adsorption sites. Finally, we quantified the average number of adsorption sites per nm2 of the C-S-H surface. All these results are the first insights into Cs retention in cement at the molecular scale and will be useful to build macroscopic diffusion models and devise cement formulations to improve radionuclide Cs retention from spent nuclear fuel.

4.
Rev Esp Enferm Dig ; 110(3): 179-194, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29421912

RESUMO

This document summarizes the contents of the Clinical Guidelines for the Endoscopic Mucosal Resection of Non-Pedunculated Colorectal Lesions that was developed by the working group of the Spanish Society of Digestive Endoscopy (GSEED of Endoscopic Resection). This document presents recommendations for the endoscopic management of superficial colorectal neoplastic lesions.


Assuntos
Neoplasias Colorretais/cirurgia , Cirurgia Colorretal/métodos , Ressecção Endoscópica de Mucosa/métodos , Endoscopia Gastrointestinal/métodos , Mucosa Intestinal/cirurgia , Doenças do Colo/cirurgia , Cirurgia Colorretal/normas , Ressecção Endoscópica de Mucosa/normas , Endoscopia Gastrointestinal/normas , Humanos , Doenças Retais/cirurgia
5.
Gastroenterol Hepatol ; 41(3): 175-190, 2018 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29449039

RESUMO

This document summarizes the contents of the Clinical Guidelines for the Endoscopic Mucosal Resection of Non-Pedunculated Colorectal Lesions that was developed by the working group of the Spanish Society of Digestive Endoscopy (GSEED of Endoscopic Resection). This document presents recommendations for the endoscopic management of superficial colorectal neoplastic lesions.


Assuntos
Neoplasias Colorretais/cirurgia , Ressecção Endoscópica de Mucosa/normas , Humanos
6.
Clin Gastroenterol Hepatol ; 14(8): 1140-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27033428

RESUMO

BACKGROUND & AIMS: After endoscopic mucosal resection (EMR) of colorectal lesions, delayed bleeding is the most common serious complication, but there are no guidelines for its prevention. We aimed to identify risk factors associated with delayed bleeding that required medical attention after discharge until day 15 and develop a scoring system to identify patients at risk. METHODS: We performed a prospective study of 1214 consecutive patients with nonpedunculated colorectal lesions 20 mm or larger treated by EMR (n = 1255) at 23 hospitals in Spain, from February 2013 through February 2015. Patients were examined 15 days after the procedure, and medical data were collected. We used the data to create a delayed bleeding scoring system, and assigned a weight to each risk factor based on the ß parameter from multivariate logistic regression analysis. Patients were classified as being at low, average, or high risk for delayed bleeding. RESULTS: Delayed bleeding occurred in 46 cases (3.7%, 95% confidence interval, 2.7%-4.9%). In multivariate analysis, factors associated with delayed bleeding included age ≥75 years (odds ratio [OR], 2.36; P < .01), American Society of Anesthesiologist classification scores of III or IV (OR, 1.90; P ≤ .05), aspirin use during EMR (OR, 3.16; P < .05), right-sided lesions (OR, 4.86; P < .01), lesion size ≥40 mm (OR, 1.91; P ≤ .05), and a mucosal gap not closed by hemoclips (OR, 3.63; P ≤ .01). We developed a risk scoring system based on these 6 variables that assigned patients to the low-risk (score, 0-3), average-risk (score, 4-7), or high-risk (score, 8-10) categories with a receiver operating characteristic curve of 0.77 (95% confidence interval, 0.70-0.83). In these groups, the probabilities of delayed bleeding were 0.6%, 5.5%, and 40%, respectively. CONCLUSIONS: The risk of delayed bleeding after EMR of large colorectal lesions is 3.7%. We developed a risk scoring system based on 6 factors that determined the risk for delayed bleeding (receiver operating characteristic curve, 0.77). The factors most strongly associated with delayed bleeding were right-sided lesions, aspirin use, and mucosal defects not closed by hemoclips. Patients considered to be high risk (score, 8-10) had a 40% probability of delayed bleeding.


Assuntos
Técnicas de Apoio para a Decisão , Ressecção Endoscópica de Mucosa/efeitos adversos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Espanha , Adulto Jovem
7.
Phys Chem Chem Phys ; 18(12): 8730-8, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26954470

RESUMO

The aggregation process, particularly the type and extent of pyronin Y (PY) laser dye intercalated into supported thin films of two different trioctahedral clay minerals, LAPONITE® (Lap) and saponite (Sap), at different dye loadings is studied: (i) experimentally by means of electronic absorption and fluorescence spectroscopy and (ii) theoretically by modeling the distribution of the dye into the interlayer space of these layered silicates. According to the results, H-type aggregates of the PY dye are favoured in Lap even at very low dye loading while a much lower molecular aggregation tendency in J-type geometry is found in Sap films. The aggregation state of PY in each clay mineral is likely attributed to different strengths of the electrostatic interactions between the dye and the layered silicate in the interlayer space due to their distinctive charge localization on the TOT clay layer (i.e. net negative charge in octahedral layers for Lap vs. in tetrahedral layers for Sap), as well as the interlaminar water distribution in each clay mineral, although other factors such as their CEC and particle size cannot be discarded. To reduce the huge aggregation processes of PY dye into Lap films, surfactant molecules (DDTAB) are co-adsorbed in the interlayer space of the clay. At an optimized surfactant concentration, the aggregation tendency of PY dye in Lap is considerably reduced enormously improving the fluorescence efficiency of the PY/Lap films. Finally, by means of anisotropic response from the hybrid films to the plane of the polarized light, the orientation of the PY molecules with respect to the normal axis of the clay layer is determined for all films (with and without surfactant) at different dye loadings.

8.
Langmuir ; 30(33): 10112-7, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25087605

RESUMO

A novel hybrid material with promising optical properties for nonlinear optical applications is presented, as formed by LDS 722 organic dye confined in Laponite clay. Thin films of the hybrid material with different dye loadings have been prepared. The film thickness, the dye and water content, and the clay swelling due to guest molecule incorporation have been characterized. Then, the photophysical properties of the thin films have been studied in detail using experimental methods and molecular simulation. As the dye load increases, the hybrid films present a hypsochromic shift in absorption and a bathochromic shift in emission. The former is attributed to the increasing strength of solvation of the dye donor group, while the latter is ascribed to a switch from an intramolecular to an intermolecular charge-transfer process as the dye load increases. The LDS 722 molecules are preferentially oriented in the host clay almost in parallel to the platelet surfaces, inducing macroscopic order that makes the material responsive to polarized light.

9.
Healthc Anal (N Y) ; 3: 100197, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37275436

RESUMO

COVID-19 pandemic has sent millions of people to hospitals worldwide, exhausting on many occasions the capacity of healthcare systems to provide care patients required to survive. Although several epidemiological research works have contributed a variety of models and approaches to anticipate the pandemic spread, very few have tried to translate the output of these models into hospital service requirements, particularly in terms of bed occupancy, a key question for hospital managers. This paper proposes a tool for predicting the current and future occupancy associated with COVID-19 patients of a hospital to help managers make informed decisions to maximize the availability of hospitalization and intensive care unit (ICU) beds and ensure adequate access to services for confirmed COVID-19 patients. The proposed tool uses a discrete event simulation approach that uses archetypes (i.e., empirical models of trajectories) extracted from empirical analysis of actual patient trajectories. Archetypes can be fitted to trajectories observed in different regions or to the particularities of current and forthcoming variants using a rather small amount of data. Numerical experiments on realistic instances demonstrate the accuracy of the tool's predictions and illustrate how it can support managers in their daily decisions concerning the system's capacity and ensure patients the access the resources they require.

10.
Nephron ; 147(9): 560-571, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37276852

RESUMO

INTRODUCTION: Inflammation is a risk factor for diabetes in the general population. The role of inflammation in prediabetes or post-transplant diabetes mellitus (PTDM) is not clear. We evaluated the association between inflammatory markers in patients on the waiting list for renal transplantation and the onset of prediabetes and PTDM 12 months after transplantation. METHODS: This is a post hoc analysis of a prospective study that included nondiabetic patients on the waiting list for kidney transplantation who underwent an oral glucose tolerance test (OGTT) and were followed up to 12 months after transplantation. At this time, those patients without PTDM underwent another OGTT. At pre-transplantation, five cytokines: TNFα, IL6, IL1ß, CRP, MCP1 were determined. The association between inflammation and prediabetes/PTDM was evaluated using multiple regression models. RESULTS: 110 patients on the waiting list were enrolled: 74 had normal glucose metabolism and 36 had prediabetes or occult diabetes. At 12 months, 53 patients had normal glucose metabolism, 25 prediabetes, and 32 PTDM. In multiple regression analysis, pre-transplant inflammation was not a risk factor for prediabetes or PTDM. This was attributed to the high interrelation between obesity, prediabetes, and inflammation: about 75% of the cases had these conditions. In a sub-analysis, we analyzed only patients without prediabetes and occult diabetes on the waiting list and found that TNFα levels and BMI at pre-transplantation were independently associated with the onset of prediabetes or PTDM 1 year after transplantation. CONCLUSIONS: Pre-transplant inflammation and BMI are risk factors for prediabetes and PTDM in patients without glucose metabolism alterations.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Humanos , Estado Pré-Diabético/etiologia , Estudos Prospectivos , Fator de Necrose Tumoral alfa , Listas de Espera , Glicemia/análise , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/etiologia , Fatores de Risco , Inflamação/complicações , Complicações Pós-Operatórias
11.
Syst Rev ; 9(1): 227, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023666

RESUMO

BACKGROUND: Patient prioritization is a strategy used to manage access to healthcare services. Patient prioritization tools (PPT) contribute to supporting the prioritization decision process, and to its transparency and fairness. Patient prioritization tools can take various forms and are highly dependent on the particular context of application. Consequently, the sets of criteria change from one context to another, especially when used in non-emergency settings. This paper systematically synthesizes and analyzes the published evidence concerning the development and challenges related to the validation and implementation of PPTs in non-emergency settings. METHODS: We conducted a systematic mixed studies review. We searched evidence in five databases to select articles based on eligibility criteria, and information of included articles was extracted using an extraction grid. The methodological quality of the studies was assessed by using the Mixed Methods Appraisal Tool. The article selection process, data extraction, and quality appraisal were performed by at least two reviewers independently. RESULTS: We included 48 studies listing 34 different patient prioritization tools. Most of them are designed for managing access to elective surgeries in hospital settings. Two-thirds of the tools were investigated based on reliability or validity. Inconclusive results were found regarding the impact of PPTs on patient waiting times. Advantages associated with PPT use were found mostly in relationship to acceptability of the tools by clinicians and increased transparency and equity for patients. CONCLUSIONS: This review describes the development and validation processes of PPTs used in non-urgent healthcare settings. Despite the large number of PPTs studied, implementation into clinical practice seems to be an open challenge. Based on the findings of this review, recommendations are proposed to develop, validate, and implement such tools in clinical settings. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018107205.


Assuntos
Atenção à Saúde , Instalações de Saúde , Hospitais , Humanos , Reprodutibilidade dos Testes
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