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1.
Rev. Nac. (Itauguá) ; 16(3): 14-29, sep-dec 2024.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1572474

RESUMEN

RESUMEN Introducción: la investigación se centra en la necesidad de validar y medir de manera confiable indicadores de gestión en el campo de la salud pública en Paraguay mediante técnicas psicométricas. Objetivo: el objetivo principal de este estudio fue desarrollar un instrumento válido y confiable para medir indicadores de gestión de salud pública en Paraguay considerando sus propiedades psicométricas. Metodología: esta investigación siguió un enfoque cuantitativo con un diseño observacional descriptivo y proposicional. Se realizó una prueba piloto utilizando escalas Likert para capturar diferentes aspectos de los indicadores de gestión de salud pública. Se realizaron análisis factoriales exploratorias y confirmatorias para validar el constructo y para el análisis estadístico se utilizó el programa JASP. La muestra incluyó a adultos de Paraguay que estuvieron relacionados con el sistema público de salud en el año anterior. Resultados: los resultados mostraron que la V de Aiken para todos los ítems fue superior a 0,7, lo que indica validez de contenido. Los índices de ajuste del análisis factorial confirmatorio como RMSEA=0,064 y CFI=0,971 demostraron una buena validez de constructo. Además, los valores alfa y omega fueron superiores a 0,9, lo que garantiza la alta confiabilidad del instrumento. Conclusión: estos resultados permitieron concluir que el instrumento desarrollado es válido y confiable para medir indicadores de gestión de salud pública en Paraguay.


ABSTRACT Introduction: this study focuses on the need to validate and reliably measure management indicators in the field of public health in Paraguay using psychometric techniques. Objective: the main objective of this study was to develop a valid and reliable instrument to measure public health management indicators in Paraguay considering its psychometric properties. Methodology: this study followed a quantitative approach using a descriptive and propositional observational design. A pilot test was conducted using Likert scales to capture different aspects of public health management indicators. Exploratory and confirmatory factor analyses were performed to validate the construct, and the JASP was used for statistical analysis. The sample included adults in Paraguay who were connected to the public health system in the previous year. Results: the results showed that Aiken's V for all items was higher than 0.7, indicating content validity. The fit indices of the confirmatory factor analysis, such as RMSEA=0.064 and CFI=0.971, demonstrated good construct validity. In addition, the alpha and omega values were higher than 0.9, which guarantees the high reliability of the instrument. Conclusion: these results indicate that the developed instrument is valid and reliable for measuring public health management indicators in Paraguay.

2.
Polymers (Basel) ; 15(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37896398

RESUMEN

The environmental degradation of the films used in packaging is a key factor in their commercial use. Industrial and academic research is aimed at obtaining materials that have degradation features that ensure their eco-sustainability but, at the same time, preserve their use properties during storage and distribution periods. This study analyzes the degradability behavior over time of commercial packaging that meets the requirements of the UNE 13432 standard and the prEN 17427 (2020) home composting certification requirements under standard storage conditions. The study attempts to provide insight into the durability of the films under standard storage conditions, verifying that this type of packaging has a useful life of more than 12 months and that after this storage period it still retains the usability properties for which it was conceived. The analyzed sample has been manufactured using a three-layer technology under some commercial formulations based on PBAT + STARCH + PLA and has been analyzed monthly for 12 consecutive months. The macroscopic monitoring of the degradation of the sample has been carried out through the evolution of the mechanical properties and the quantification of the color changes (very important in films) via colorimetry. The nature of the observed variations has been justified at the microstructural level from the data obtained in calorimetric analysis (DSC) and from the characterization using FTIR. The results indicate a loss of properties in the tensile, elongation and impact tests and a behavior of stability or improvement in the tear properties of the film. Analyzing the microstructural changes, it is observed that the degradation of a hydrolytic and thermo-oxidative type occurs in the amorphous part of the film. The conclusion of this study is that the proposed packaging, focused on domestic composting and stored under standard conditions, has a useful life of more than 12 months. This period should be sufficient to cover the stages of production, storage and final use.

3.
Foods ; 12(4)2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36832878

RESUMEN

Olive tree crops and the olive oil market are becoming less and less diverse due to the rise of intensive growth varieties, with the consequent loss of varietal richness provided by oils from minority and autochthonous cultivars. "Royal de Calatayud" and "Negral de Sabiñán" are two local minority cultivars in Aragon (Spain). Fruit parameters such as ripening, fresh weight, and oil yield were evaluated, as well as physico-chemical and chemical composition parameters in olive oil in comparison with "Arbequina", a cultivar widespread in Spain and other countries. Fruits were harvested from October to December in 2017 and 2019. Chemometric analysis revealed significant varietal differences among the three cultivars. In comparison with "Arbequina", higher oil yields were obtained in the two local cultivars. "Royal de Calatayud" has a higher oleic acid content and a greater quantity of phenolic compounds. It thus displays a better nutritional profile than "Arbequina". This preliminary study shows that "Royal de Calatayud" could be regarded as an excellent alternative to the "Arbequina" cultivar in the parameters analyzed.

4.
Vet Pathol ; 60(2): 178-184, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36683413

RESUMEN

Odontogenic neoplasms demonstrate unique histopathological features and are thought to arise from the germinal tissues of the developing tooth germ, effectively restricting their anatomic origin to the tooth-bearing regions of the jaw and directly associated soft tissues of the oral cavity. Ectopic odontogenic-like neoplasms located in the skin of cats, rabbits, and human beings challenge these assumptions. Here we describe the clinical, pathological, and immunohistochemical features of 6 spontaneously occurring odontogenic-like neoplasms arising in the cutaneous tissue of the cheek in client-owned pet rabbits, including ameloblastoma-like (n = 3), ameloblastic fibroma-like (n = 2), and ameloblastic carcinoma-like neoplasms (n = 1). Microscopically, all the cheek tumors featured neoplastic epithelium exhibiting odontogenic architectural structures (plexiform ribbons, anastomosing trabeculae, follicles, cysts, and irregular structures with rounded botryoid protuberances) and 1 or more cardinal odontogenic epithelial features (basal palisading, antibasilar nuclei, and central stellate reticulum-like cells). The pancytokeratin, cytokeratin 5/6, cytokeratin 14, and vimentin immunohistochemical patterns of these odontogenic-like lesions were most similar to those of jaw-associated ameloblastoma and differed from those of cutaneous trichoblastoma. All neoplasms were narrowly excised, and for lesions with clinical follow-up information, none had evidence of recurrence 1-7 months after surgical removal. Although evidence suggests that these odontogenic-like tumors of the rabbit cheek may be derived from ectopic rests of transformed tooth germ, the histogenesis of these lesions remains unresolved.


Asunto(s)
Ameloblastoma , Tumores Odontogénicos , Neoplasias Cutáneas , Conejos , Humanos , Animales , Ameloblastoma/química , Ameloblastoma/patología , Ameloblastoma/veterinaria , Mejilla/patología , Tumores Odontogénicos/patología , Tumores Odontogénicos/veterinaria , Epitelio/patología , Piel/patología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/veterinaria
5.
Surg Endosc ; 36(7): 5094-5103, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34846592

RESUMEN

BACKGROUND: More than 20 million inguinal hernia repair (IHR) procedures are performed worldwide every year. The critical view of the myopectineal orifice (CV of the MPO) is a stepwise guide to the achievement and standardization of minimally invasive IHR (MI IHR). We propose a scoring system as an objective method for fulfillment of the CV of the MPO. METHODS: The scoring system was employed for evaluation of the transabdominal preperitoneal (TAPP) technique in 15 video-recorded procedures. Two variants of the score were used: the simple CV of the MPO score (s-CVMPO score) and the extended CV of the MPO score (e-CVMPO score). The inter-rater agreement and internal consistency for both scores and the correlation between the two scores were assessed. RESULTS: Inter-rater agreement with respect to satisfactory/unsatisfactory achievement of the CV of the MPO was high for both the s-CVMPO and e-CVMPO scores (κ = 1, p < 0.001). The Finn coefficient for inter-rater agreement was 0.97 for the s-CVMPO score and 0.99 for the e-CVMPO score (p < 0.001 for both). Both the s-CVMPO and e-CVMPO scores showed internal consistency with Cronbach's α of 0.89 and 0.87, respectively. The correlation coefficient between the two scores for the average score of each procedure was ρ = 0.96 (p < 0.001). CONCLUSION: The CVMPO score is a reliable tool for expert evaluation of TAPP repair. Implementing the CVMPO score facilitates objective assessment of the safety and quality of the procedure.


Asunto(s)
Hernia Inguinal , Laparoscopía , Hernia Inguinal/cirugía , Herniorrafia/métodos , Humanos , Laparoscopía/métodos , Mallas Quirúrgicas
6.
J Am Chem Soc ; 142(24): 10863-10868, 2020 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-32449618

RESUMEN

The molecular connectivity of polymer-metal-organic framework (polyMOF) hybrid materials was investigated using density functional theory calculations and solid-state NMR spectroscopy. The architectural constraints that dictate the formation of polyMOFs were assessed by examining poly(1,4-benzenedicarboxylic acid) (pbdc) polymers in two archetypical MOF lattices (UiO-66 and IRMOF-1). Modeling of the polyMOFs showed that in the IRMOF-1-type lattice, six, seven, and eight methylene (-CH2-) groups between 1,4-benzenedicarboxylate (terephthalate, bdc2-) units can be accommodated without significant distortions, while in the UiO-66-type lattice, an optimal spacing of seven methylene groups between bdc2- units is needed to minimize strain. Solid-state NMR supports these predictions and reveals pronounced spectral differences for the same polymer in the two polyMOF lattices. With seven methylene groups, polyUiO-66-7a shows 7 ± 3% of uncoordinated terephthalate linkers, while these are undetectable (<4%) in the corresponding polyIRMOF-1-7a. In addition, NMR-detected backbone mobility is significantly higher in the polyIRMOF-1-7a than in the corresponding polyUiO-66-7a, again indicative of taut chains in the latter.

7.
PLoS One ; 15(3): e0230220, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32163505

RESUMEN

Helicobacter pylori is a Gram-negative bacterium that causes chronic atrophic gastritis and peptic ulcers and it has been associated with the development of gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT). One of the more remarkable characteristics of H. pylori is its ability to survive in the hostile environment of the stomach. H. pylori regulates the expression of specific sets of genes allowing it to survive high acidity levels and nutrient scarcity. In the present study, we determined the expression of virulence associated protein D (VapD) of H. pylori inside adenocarcinoma gastric (AGS) cells and in gastric biopsies. Using qRT-PCR, VapD expression was quantified in intracellular H. pylori-AGS cell cultures at different time points and in gastric mucosa biopsies from patients suffering from chronic atrophic gastritis, follicular gastritis, peptic ulcers, gastritis precancerous intestinal metaplasia and adenocarcinoma. Our results show that vapD of H. pylori presented high transcription levels inside AGS cells, which increased up to two-fold above basal values across all assays over time. Inside AGS cells, H. pylori acquired a coccoid form that is metabolically active in expressing VapD as a protection mechanism, thereby maintaining its permanence in a viable non-cultivable state. VapD of H. pylori was expressed in all gastric biopsies, however, higher expression levels (p = 0.029) were observed in gastric antrum biopsies from patients with follicular gastritis. The highest VapD expression levels were found in both antrum and corpus gastric biopsies from older patients (>57 years old). We observed that VapD in H. pylori is a protein that is only produced in response to interactions with eukaryotic cells. Our results suggest that VapD contributes to the persistence of H. pylori inside the gastric epithelial cells, protecting the microorganism from the intracellular environment, reducing its growth rate, enabling long-term infection and treatment resistance.


Asunto(s)
Proteínas Bacterianas/genética , Gastritis Atrófica/etiología , Helicobacter pylori/genética , Glicoproteínas de Membrana/genética , Estómago/microbiología , Estómago/patología , Adenocarcinoma/etiología , Adenocarcinoma/microbiología , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Técnicas de Cocultivo/métodos , Femenino , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Gastritis Atrófica/microbiología , Gastritis Atrófica/patología , Gastroscopía/métodos , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/patología , Humanos , Intestinos/microbiología , Intestinos/patología , Masculino , Metaplasia/microbiología , Metaplasia/patología , Persona de Mediana Edad , Úlcera Péptica/metabolismo , Úlcera Péptica/patología , Lesiones Precancerosas/etiología , Lesiones Precancerosas/microbiología , Lesiones Precancerosas/patología , Antro Pilórico/microbiología , Antro Pilórico/patología , Neoplasias Gástricas/etiología , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Virulencia/genética , Adulto Joven
8.
Chem Rev ; 120(16): 8267-8302, 2020 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-31895556

RESUMEN

Metal-organic frameworks (MOFs) are inherently crystalline, brittle porous solids. Conversely, polymers are flexible, malleable, and processable solids that are used for a broad range of commonly used technologies. The stark differences between the nature of MOFs and polymers has motivated efforts to hybridize crystalline MOFs and flexible polymers to produce composites that retain the desired properties of these disparate materials. Importantly, studies have shown that MOFs can be used to influence polymer structure, and polymers can be used to modulate MOF growth and characteristics. In this Review, we highlight the development and recent advances in the synthesis of MOF-polymer mixed-matrix membranes (MMMs) and applications of these MMMs in gas and liquid separations and purifications, including aqueous applications such as dye removal, toxic heavy metal sequestration, and desalination. Other elegant ways of synthesizing MOF-polymer hybrid materials, such as grafting polymers to and from MOFs, polymerization of polymers within MOFs, using polymers to template MOFs, and the bottom-up synthesis of polyMOFs and polyMOPs are also discussed. This review highlights recent papers in the advancement of MOF-polymer hybrid materials, as well as seminal reports that significantly advanced the field.

9.
Chem Sci ; 11(38): 10523-10528, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34123187

RESUMEN

In this report, we explore the internal structural features of polyMOFs consisting of equal mass ratios of metal-coordinating poly(benzenedicarboxylic acid) blocks and non-coordinating poly(ethylene glycol) (PEG) blocks. The studies reveal alternating lamellae of metal-rich, crystalline regions and metal-deficient non-crystalline polymer, which span the length of hundreds of nanometers. Polymers consisting of random PEG blocks, PEG end-blocks, or non-coordinating poly(cyclooctadiene) (COD) show similar alternation of metal-rich and metal-deficient regions, indicating a universal self-assembly mechanism. A variety of techniques were employed to interrogate the internal structure of the polyMOFs, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and small-angle synchrotron X-ray scattering (SAXS). Independent of the copolymer architecture or composition, the internal structure of the polyMOF crystals showed similar lamellar self-assembly at single-nanometer length scales.

10.
Chem Sci ; 10(6): 1746-1753, 2019 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-30842840

RESUMEN

The hybridization of block copolymers and metal-organic frameworks (MOFs) to create novel materials (block co-polyMOFs, BCPMOFs) with controlled morphologies is reported. In this study, block copolymers containing poly(1,4-benzenedicarboxylic acid, H2bdc) and morphology directing poly(ethylene glycol) (PEG) or poly(cyclooctadiene) (poly(COD)) blocks were synthesized for the preparation of BCPMOFs. Block copolymer architecture and weight fractions were found to have a significant impact on the resulting morphology, mediated through the assembly of polymer precursors prior to MOF formation, as determined through dynamic light scattering. Simple modification of block copolymer weight fraction allowed for tuning of particle size and morphology with either faceted and spherical features. Modification of polymer block architecture represents a simple and powerful method to direct morphology in highly crystalline polyMOF materials. Furthermore, the BCPMOFs could be prepared from both Zr4+ and Zn2+ MOFs, yielding hybrid materials with appreciable surface areas and tuneable porosities. The resulting Zn2+ BCPMOF yielded materials with very narrow size distributions and uniform cubic morphologies. The use of topology in BCPMOFs to direct morphology in block copolymer assemblies may open new methodologies to access complex materials far from thermodynamic equilibrium.

11.
Sci Adv ; 4(7): eaar5954, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30009257

RESUMEN

American archeology has long been polarized over the issue of a human presence in the Western Hemisphere earlier than Clovis. As evidence of early sites across North and South America continues to emerge, stone tool assemblages appear more geographically and temporally diverse than traditionally assumed. Within this new framework, the prevailing models of Clovis origins and the peopling of the Americas are being reevaluated. This paper presents age estimates from a series of alluvial sedimentary samples from the earliest cultural assemblage at the Gault Site, Central Texas. The optically stimulated luminescence age estimates (~16 to 20 thousand years ago) indicate an early human occupation in North America before at least ~16 thousand years ago. Significantly, this assemblage exhibits a previously unknown, early projectile point technology unrelated to Clovis. Within a wider context, this evidence suggests that Clovis technology spread across an already regionalized, indigenous population.


Asunto(s)
Arqueología , Fósiles/historia , Historia Antigua , Actividades Humanas/historia , Humanos , América del Norte , Tecnología , Texas
12.
Chem Commun (Camb) ; 53(77): 10684-10687, 2017 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-28913536

RESUMEN

The concept of isoreticular chemistry has become a core principle in metal-organic framework (MOF) materials. Isoreticular chemistry has shown that organic ligands of different sizes, but with a common geometry/symmetry can be used to generate MOFs of related topologies, but with expanded pore sizes and volumes. In this report, polymer-MOF hybrid materials (polyMOFs) with a UiO (UiO = University of Oslo) architecture are shown to adhere to the principle of isoreticular expansion, generating polyMOFs with large surface areas and enhanced stability.

13.
Chem Commun (Camb) ; 53(21): 3058-3061, 2017 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-28240327

RESUMEN

The first polymer-MOF hybrid material (polyMOF) with a UiO-66 architecture is reported, prepared from polymers with varying alkyl spacers, molecular weights, and dispersities. With appropriate spacing, mesoporous UiO-66 polyMOF can be obtained having an uncommon, interlaced crystal morphology, suggesting that polyMOFs can be used to generate MOF materials with hierarchical architectures.

14.
J Am Chem Soc ; 136(46): 16128-31, 2014 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-25348857

RESUMEN

A new self-healing multiphase polymer is developed in which a pervasive network of dynamic metal-ligand (zinc-imidazole) interactions are programmed in the soft matrix of a hard/soft two-phase brush copolymer system. The mechanical and dynamic properties of the materials can be tuned by varying a number of molecular parameters (e.g., backbone/brush degree of polymerization and brush density) as well as the ligand/metal ratio. Following mechanical damage, these thermoplastic elastomers show excellent self-healing ability under ambient conditions without any intervention.

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