Mayenite inorganic electrides are antizeolite nanoporous materials with variable electron concentration Ca12Al14O322+□5- δO1- δ 2-e2 δ - (0 < δ ≤ 1), where □ stands for empty sites. The oxymayenite ...crystal structure contains positively charged cages where loosely bounded oxide anions are located. These oxygens can be removed to yield electron-loaded materials in which the electrons behave like anions (electrides). Here, a new preparation method, which allows synthesizing powder mayenite electrides easily, is reported. Accurate structural data for the white (δ = 0) and green electride (δ ∼ 0.5) are reported from joint Rietveld refinements of neutron and synchrotron X-ray powder diffraction data and also from single-crystal diffraction. The electride formation at high temperature under vacuum has been followed in-situ by neutron powder diffraction. The evolution of mayenite crystal structure, including the changes in the key occupation factor of the intracage oxide anions, is reported. Furthermore, the stability of mayenite framework in very low oxygen partial pressure conditions is also studied. It has been found that C12A7 decomposes, at 1373 K in reducing conditions, to give Ca5Al6O14 (C5A3) and Ca3Al2O6 (C3A). The kinetics of this transformation has also been studied. The fit of the transformed fraction to the classic Avrami−Erofe'ev equation gave an “Avrami exponent”, n = 2, which indicates that nucleation is fast and the two-dimensional linear growth of the new phases is likely to be the limiting factor.
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IJS, KILJ, NUK, PNG, UL, UM
12.
Corrector atmosférico en imágenes Landsat Paz Pellat, Fernando; Palacios Sánchez, Luis Alberto; Oropeza Mota, José Luis ...
REVISTA TERRA LATINOAMERICANA,
10/2018, Volume:
36, Issue:
4
Journal Article
Peer reviewed
Open access
Los efectos atmosféricos en las imágenes satelitales distorsionan la información disponible y originan errores en la estimación de las variables biofísicas provenientes de los datos espectrales. En ...este trabajo se desarrolló un algoritmo de corrección atmosférica que se basó en la correlación existente entre la reflectancia de la banda 7 (infrarrojo medio, 2.2 μm) y la banda 1 (Azul, 0.485 μm) de la vegetación, para los sensores TM y ETM+. La ordenada al origen de la regresión entre la banda 7 y la banda 1 de imágenes Landsat es un estimador de la reflectancia de trayectoria en la banda 1. Con esta reflectancia de trayectoria y un modelo de atmósfera y aerosol def inido, es posible estimar el espesor óptico de los aerosoles centrado en 0.55 μm. El algoritmo se apoyó en el acoplamiento de varios modelos de simulación y bibliotecas de datos espectrales para la representación del sistema óptico suelo–vegetación–atmósfera. La vegetación en una imagen se identif ica mediante un clasif icador genérico de objetos en cuatro variantes: oscura densa, cobertura alta, media y baja. El algoritmo se probó en dos fases, la primera se basó en un análisis empírico sobre los resultados de la simulación del sistema óptico suelo–vegetación–atmósfera, en el que se tenían condiciones controladas. En la segunda fase se validó el algoritmo con 7 imágenes ETM+ cuyas escenas contenían un sitio de la red robótica de aerosoles (AERONET), la cual mide con gran precisión el espesor óptico de los aerosoles en diferentes intervalos de longitud de onda. El análisis de los resultados mostró que el corrector estima el espesor óptico de la escena con un ajuste: R2 = 0.97, error típico de 0.059 (20.3%) y que representa bien la variabilidad espacial de carga de aerosoles en imágenes Landsat.
To describe the patterns of diabetic ketoacidosis (DKA) occurrence in children newly diagnosed with type 1 diabetes (T1DM) across several Latin American pediatric diabetes centers from 2018 to 2022.
...A retrospective chart review included children under 18 with new-onset T1DM from 30 Latin American pediatric diabetes centers (Argentina, Chile, and Peru) between 30 December 2018 and 30 December 2022. Multiple logistic regression models examined the relationships between age, gender, medical insurance, BMI, and DKA at new-onset T1DM. As far as we know, there are no large studies in Latin American countries exploring the patterns of DKA in new-onset T1DM.
A total of 2,026 (983 females) children, median age 9.12 (5.8 -11.7) years with new-onset-T1DM were included. Approximately 50% had no medical insurance. Mean glucose values were 467 mg/dL, pH 7.21, bicarbonate 13 mEq/L, HbA1c 11.3%, and BMI 18. The frequency of DKA was 1,229 (60.7%), out of which only 447 (36%) were severe. There was a significant decrease in the frequency of DKA as age increased: 373 (70.2%) in children under 6, 639 (61.6%) in those between 6 and 12, 217 and (47.5%) in those over 12. Children with medical insurance (58.8%) had a significantly lower frequency of DKA than those without (62.7%). The multiple logistic regression models showed that DKA was significantly and inversely associated with age OR, 0.72 (95% CI 0.60–0.86), BMI OR, 0.95 (95% CI 0.92–0.99), and medical insurance OR, 0.75 (95% CI 0.60–0.94) adjusted for sex.
Latin American children with new-onset T1DM exhibited a substantial occurrence of DKA. Younger ages and the lack of medical insurance were significantly associated with DKA in new-onset T1DM.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Malignant melanoma (MM) is a highly aggressive form of skin cancer whose incidence continues to rise worldwide. If diagnosed at an early stage, it has an excellent prognosis, but mortality increases ...significantly at advanced stages after distant spread. Unfortunately, early detection of aggressive melanoma remains a challenge.
To identify novel blood-circulating biomarkers that may be useful in the diagnosis of MM to guide patient counselling and appropriate disease management.
In this study, 105 serum samples from 26 healthy patients and 79 with MM were analysed using an untargeted approach by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) to compare the metabolomic profiles of both conditions. Resulting data were subjected to both univariate and multivariate statistical analysis to select robust biomarkers. The classification model obtained from this analysis was further validated with an independent cohort of 12 patients with stage I MM.
We successfully identified several lipidic metabolites differentially expressed in patients with stage I MM vs. healthy controls. Three of these metabolites were used to develop a classification model, which exhibited exceptional precision (0.92) and accuracy (0.94) when validated on an independent sample.
These results demonstrate that metabolomics using LC-HRMS is a powerful tool to identify and quantify metabolites in bodily fluids that could serve as potential early diagnostic markers for MM.
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BFBNIB, FZAB, GIS, IJS, KILJ, OILJ, SBCE, SBMB, UPUK
Introducción: el traumatismo encéfalo craneano es una de las principales causas de muerte en nuestro medio, El tratamiento médico y quirúrgico en la etapa inicial de un TEC severo se enfoca en evitar ...la elevación de la Presión Intracraneana. Objetivo: describir características asociados y sus principales complicaciones en aquellos pacientes sometidos a Craniectomía Descompresiva. Métodos: Estudio retrospectivo observacional descriptivo, realizado entre febrero de 2018 a julio de 2020 de pacientes operados de Craniectomía Descompresiva unilateral, admitidos por traumatismo encefalocraneano. Resultados: 66.7% fueron personas menores de 40 años; 87,5% fueron de sexo masculino; 16,7% de la población ingresaron con una ECG de 13-15, 37,5% de la población con una ECG de 9-12; 42.9% presentaron asimetría pupilar; 33,3% ingresaron por accidente de tránsito; 21,7% fueron Marshall II, 65,2% Marshall III y en 13,0% se halló un Marshall IV. Conclusiones: Los resultados sugieren que las características asociadas a la Craniectomía Descompresiva por TEC contribuyen en el manejo de esta patología.
Desmoid tumors are clinical entities rarely diagnosed at an initial presentation because of its low incidence, they are characterized by a locally aggressive presentation and high rates of local ...relapse. Its presentation can be intra- or extra-abdominal. We present a clinical case of a female, 15 year old patient, with three months of abdominal pain, a giant intra-abdominal mass was diagnosed with histologic diagnosis of desmoid tumor. Several surgical procedures were performed, having a las a R1 resection (focally microscopic margins). In this case association with pregnancy, abdominal trauma, previous surgeries and genetic syndromes were discarded.
Los tumores desmoides son afecciones benignas raramente reconocidas de manera inicial por su baja incidencia. Se caracterizan por un comportamiento local agresivo y altas tasas de recurrencia. Su ...presentación puede ser extraabdominal o intraabdominal. Presentamos el caso de una paciente de 15 años con cuadro de dolor abdominal de 3 meses de evolución, en la que se documentó una gran masa intraabdominal con diagnóstico histológico de tumor desmoide y fue sometida a múltiples intervenciones quirúrgicas con las que se logró una resección R1 (microscópicamente positivo). Se descartó su asociación con embarazo, trauma abdominal, cirugías previas y síndromes genéticos.
There are different techniques for obtaining tissue using a fine needle guided by endoscopic ultrasound (EUS); all aim to obtain the most appropriate material, free of defects, of good quality and in ...sufficient quantity.
The objective of the study was to determine which of the two EUS-guided techniques (capillary and wet) provides better quality samples for cytopathological analysis and which should be used for obtaining tissue from pancreatic, bile duct, liver, and lymph node tumors.
We conducted a pilot prospective study that included 26 patients with evidence of pancreatic tumor, liver tumor, and/or lymph node metastasis of primary tumor. All patients were subjected to two different tissue sampling techniques, the capillary technique and the wet technique, during the same procedure. Both techniques relied on EUS guidance. The samples obtained for the cytopathological analysis were evaluated in blinded manner by two different pathologists.
Pathologist A was able to make a diagnosis using the capillary technique in 96.15% of the cases and in 88.46% of the cases using the wet technique. Pathologist B was able to make a diagnosis using the capillary technique in 96.15% of the cases and in 92.30% of the cases using the wet technique. The kappa coefficient between observers for histopathological diagnosis was 1 for capillarity and 0.948 for wet technique.
The capillary technique yielded better results than the wet technique in terms of sample quality and cellularity.
Abstract only
e21555
Background: Lung-ONE study aims to determine the clinical utility in making decisions on planned 2
nd
line therapy in advanced NSCLC based on a comprehensive genomic profile ...(CGP) test as FoundationOne CDx or FoundationOne Liquid and describe alterations found on these patients. Methods: Lung-ONE included advanced/metastatic NSCLC patients being treated on first-line, with molecular diagnostic wild-type (or unknown) for at least ALK, EGFR, and ROS-1 genes. Patients treated with targeted therapies or immunotherapy were excluded. This interim analysis describes the findings of CGP from patients of Lung-ONE with driver genomic alterations (GAs) and the investigators decision to change the planned second line treatment or not. Patients continue being followed-up for up to 2 years. Results: As of November 15 2019, 152 patients were included. At the time of sampling, 90.7% had received ≥2 different chemotherapy regimens and other therapies. Main testing for ALK and ROS-1 was IHC in 91.4% and 73.8%, respectively; and for EGFR, it was qPCR in 99.3%. Planned 2nd-line based on routine molecular profile was chemotherapy and, mainly checkpoint inhibitors (61.7%). CGP was assayed on 102 (67.1%) tissue specimens and 50 (32.9%) blood samples. Of the 1,581 GAs identified in 141 patients, 541(34.2%) were potential drivers in 131. The most frequently mutated genes were TP53 in 72(55%) patients and KRAS in 52(40%). TMB and MSI signatures were calculated on 82 patients. 21% had < = 16 mut/Mb. Other GAs of interest are presented in table. Therapeutic orientations were recommended for 116/152(76.8%) patients. In 39/151(25.8%) patients the GAs had approved drugs in NSCLC or other tumor types. CGP outcomes, would be used by 27% of oncologists to guide targeted 2nd-line. Conclusions: CGP detected mutations that are informative for choosing personalized treatment in 25%. CGP demonstrates the ability of detect druggable genomic alterations missed at diagnosis opening new treatment options. Table: see text
Introduction
The identification and validation of biomarkers of chemotherapy sensitivity is critical in order to individualise therapy in breast cancer. We evaluated pathological complete response ...(pCR) to GAT, and its correlation with tumour biomarkers before and after neoadjuvant chemotherapy.
Materials and methods
Stage III (and stage II with T≥5 cm) breast cancer patients were included. Treatment consisted of adriamycin (40 mg/m
2
) day 1, and paclitaxel (150 mg/m
2
) followed by gemcitabine (2000 mg/m
2
) day 2, every 14 days for six cycles. Tissue from pre-treatment biopsy and surgery was evaluated for biologic markers by immunohistochemistry. Two XPD single nucleotide polymorphisms (SNP) were also analysed.
Results
Forty-six patients entered the trial. Median age was 49.5 years (range 31–72); 25 patients (54%) were pre-menopausal; 12 (26%) were ER-PgR-negative; pCR was observed in 17% (95% CI: 6.4–28.4) of patients. Significant differences in marker expression (mean±SD) in correlation to pathological response were only found in Ki-67. After treatment, tumours showed lower Ki-67-, surviving- and pERK-positive cells. No correlation between XPD polymorphisms and pCR was found. The overall response rate was 89% (95% CI: 80.1–98.1). Fifteen patients (33%) underwent breast-conserving surgery. The most frequent grade 3 or 4 toxicities were neutropenia (with one febrile neutropenia) and asthenia.
Conclusion
These results show an effective regimen with acceptable tolerability. Our data suggest that not only classical markers (ER, Ki-67), but also survivin and pERK could be involved in the response to GAT, which may contribute to therapy individualisation in future study designs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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