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Plasmonic polymeric nanoassemblies offer valuable opportunities in photoconversion applications. Localized surface plasmon mechanisms behind such nanoassemblies govern their functionalities under light illumination. However, an in-depth investigation at the single nanoparticle (NP) level is still challenging, especially when the buried interface is involved, due to the availability of suitable techniques. Here, we synthesized an anisotropic heterodimer composed of a self-assembled polymer vesicle (THPG) capped with a single gold NP, enabling an 8-fold enhancement in hydrogen generation compared to the nonplasmonic THPG vesicle. We explored the anisotropic heterodimer at the single particle level by employing advanced transmission electron microscopes, including one equipped with a femtosecond pulsed laser, which allows us to visualize the polarization- and frequency-dependent distribution of the enhanced electric near fields at the vicinity of Au cap and Au-polymer interface. These elaborated fundamental findings may guide designing new hybrid nanostructures tailored for plasmon-related applications.
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We use a gold nanoparticle synthesis as a model system to study the morphological and compositional changes in gold(III) precursor particles, while reduction is taking place during aging after mechanical activation. Scanning transmission electron microscopy coupled with a high-angle annular dark field detector revealed the nanoscale changes in particle morphology, while electron energy loss spectroscopy mapped the changes in the chemical landscape during the reduction process. Tracking a specific region of interest on the sample grid allowed for comparisons to be made of the same particles across a two day monitoring period. High-angle annular dark field images permitted the visualization of particle size reduction of the gold salt while electron energy loss spectroscopy captured the surprising mobility of the lighter chlorine and sodium ions in a solid matrix during the reduction process. This system offers unique insight into precursor particle reactivity in the solid phase, which is relevant for many mechanochemical and aging-based reactions.
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Herein, we present the bottom-up, mechanochemical synthesis of phosphorus-bridged heptazine-based carbon nitrides (g-h-PCN). The structure of these materials was determined through a combination of powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), 31P magic angle spinning nuclear magnetic resonance (MAS NMR), density functional theory (DFT) and electron energy loss spectroscopy (EELS). Compared to traditional furnace-based techniques, the presented method utilizes milder conditions, as well as shorter reaction times. Both samples of g-h-PCN directly after milling and aging and after an hour of annealing at 300 °C (g-h-PCN300) show a reduction in photoluminescent recombination, as well as a nearly two-time increase in photocurrent under broad spectrum irradiation, which are appealing properties for photocatalysis.
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The high-Sensitivity C-Reactive Protein (hs-CRP) is a cardiovascular risk marker. In healthy Mexican children, there islittle evidence that shows any relationship between serum levels of this marker with diet. The objective of this studywas to associate serum levels of hs-CRP with the diet composition in Mexican school children. The cross-sectional study included 300 seemingly healthy children of 10 to 12 years of age, 53.7% were girls and 46.3% boys.hs-CRP quantification was determined by nephelometry. The diet was quantified with a validated food frequency questionnaire. A descriptive statistical analysis, correlation and multivariate regression models were performed by using the SPSS v18 statistical software. The median of the hs-CRP was 0.3 mg / L (range: 0.3 to 6.8 mg / L). A significant direct correlation was found between serum hs-CRP with protein intake (rho=0.126, p=0.029), total fatty acids (rho = 0.128, p = 0.027) and saturated fatty acids (rho = 0.159, p = 0.006). hs-CRP was associated with the intake of protein (ß = 0.203, p = 0.037) by multiple regression analysis, and inversely with whole grains (ß = -0.175, p = 0,002). No significant association was found with the rest of the other variables. The serum concentration of hs-CRP was directly associated with the consumption of protein, total and saturated fatty acids and was indirectly proportional with the consumption of whole grains.
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Proteína C-Reactiva/análisis , Dieta , Alimentos , Niño , Estudios Transversales , Femenino , Humanos , Masculino , México , Estudios ProspectivosRESUMEN
BACKGROUND: Respiratory syncytial virus (RSV) causes severe respiratory infection in infants, children and elderly. Currently, there is no effective vaccine or RSV specific drug for the treatment. However, an antiviral drug ribavirin and palivizumab is prescribed along with symptomatic treatment. RSV detection is important to ensure appropriate treatment of children. Most commonly used detection methods for RSV are DFA, ELISA and Real-time PCR which are expensive and time consuming. Newer approach of plasmonic detection techniques like localized surface plasmon resonance (LSPR) spectroscopy using metallic nanomaterials has gained interest recently. The LSPR spectroscopy is simple and easy than the current biophysical detection techniques like surface-enhanced Raman scattering (SERS) and mass-spectroscopy. RESULTS: In this study, we utilized LSPR shifting as an RSV detection method by using an anti-RSV polyclonal antibody conjugated to metallic nanoparticles (Cu, Ag and Au). Nanoparticles were synthesized using alginate as a reducing and stabilizing agent. RSV dose and time dependent LSPR shifting was measured for all three metallic nanoparticles (non-functionalized and functionalized). Specificity of the functionalized nanoparticles for RSV was evaluated in the presence Pseudomonas aeruginosa and adenovirus. We found that functionalized copper nanoparticles were efficient in RSV detection. Functionalized copper and silver nanoparticles were specific for RSV, when tested in the presence of adenovirus and P. aeruginosa, respectively. Limit of detection and limit of quantification values reveal that functionalized copper nanoparticles are superior in comparison with silver and gold nanoparticles. CONCLUSIONS: The study demonstrates successful application of LSPR for RSV detection, and it provides an easy and inexpensive alternative method for the potential development of LSPR-based detection devices.
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Nanopartículas del Metal/química , Virus Sincitiales Respiratorios/química , Plata/química , Adenoviridae/efectos de los fármacos , Anticuerpos Antivirales/química , Anticuerpos Antivirales/inmunología , Antivirales/farmacología , Cobre/química , Oro/química , Palivizumab/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Virus Sincitiales Respiratorios/efectos de los fármacos , Sensibilidad y Especificidad , Resonancia por Plasmón de Superficie/métodosRESUMEN
BACKGROUND: Pregnancy during adolescence has been rising in the past years, and it is well known that preeclampsia affects teenagers, because maternal age and primigravida are risk factors. There are different ways and methods to predict preeclampsia, for example doppler velocimetry. OBJECTIVE: Determine S/D ratio of uterine artery in pregnant teenagers between 24-28 weeks and correlation with preeclampsia. MATERIAL AND METHOD: Observational study in 50 pregnant teenagers (14-19 years) obtaining uterine artery waveform at 24-28 weeks gestation recording S/D ratio. RESULTS: Sensitivity and specificity of 90% with a positive predictive value of 69.23% and negative predictive value of 97.3%. 13 patients had S/D ratio greater than 2.6, of which 5 had gestational hypertension, 3 with preeclampsia, 1 with Fetal Growth Restriction, 4 with normal pregnancy. Relative Risk was 25.62 (3.58-183.13) with odds ratio of 81.00 (6.83-2260.88) and p value 0.00002. CONCLUSION: analysis of uterine artery flow velocity waveforms is a method to predict preeclampsia.
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Retardo del Crecimiento Fetal/diagnóstico , Hipertensión Inducida en el Embarazo/diagnóstico , Preeclampsia/diagnóstico , Arteria Uterina/metabolismo , Adolescente , Velocidad del Flujo Sanguíneo , Femenino , Retardo del Crecimiento Fetal/fisiopatología , Humanos , Hipertensión Inducida en el Embarazo/fisiopatología , Flujometría por Láser-Doppler , Edad Materna , Preeclampsia/fisiopatología , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Adulto JovenRESUMEN
As we strive to perform chemical transformations in a more sustainable fashion, enabling solid-state reactions through mechanochemistry has emerged as a highly successful approach. Due to the wide-ranging applications of gold nanoparticles (AuNPs), mechanochemical strategies have already been employed for their synthesis. However, the underlying processes surrounding gold salt reduction, nucleation and growth of AuNPs in the solid state are yet to be understood. Here, we present a mechanically activated aging synthesis of AuNPs, through a solid-state Turkevich reaction. Solid reactants are only briefly exposed to input of mechanical energy before being aged statically over a period of six weeks at different temperatures. This system offers an excellent opportunity for an in situ analysis of both reduction and nanoparticle formation processes. During the aging period, the reaction was monitored using a combination of X-ray photoelectron spectroscopy, diffuse reflectance spectroscopy, powder X-ray diffraction and transmission electron microscopy, to gain meaningful insights into the mechanisms of solid-state formation of gold nanoparticles. The acquired data allowed for the establishment of the first kinetic model for solid-state nanoparticle formation.
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Polymer-inorganic hybrid Janus nanoparticles (PI-JNPs) have attracted extensive attention due to their special structures and functions. However, achieving the synergistic enhancement of photochemical activity between polymer and inorganic moieties in PI-JNPs remains challenging. Herein, the construction of a novel Janus Au-porphyrin polymersome (J-AuPPS) heterostructure by a facile one-step photocatalytic synthesis is reported. The near-field enhancement (NFE) effect between porphyrin polymersome (PPS) and Au nanoparticles in J-AuPPS is achieved to enhance its near-infrared (NIR) light absorption and electric/thermal field intensity at their interface, which improves the energy transfer and energetic charge-carrier generation. Therefore, J-AuPPS shows a higher NIR-activated photothermal conversion efficiency (48.4%) and generates more singlet oxygen compared with non-Janus core-particle Au-PPS nanostructure (28.4%). As a result, J-AuPPS exhibits excellent dual-mode (photothermal/photodynamic) antibacterial and anti-biofilm performance, thereby significantly enhancing the in vivo therapeutic effect in an implant-associated-infection rat model. This work is believed to motivate the rational design of advanced hybrid JNPs with desirable NFE effect and further extend their biological applications.
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Nanopartículas del Metal , Nanopartículas , Nanoestructuras , Ratas , Animales , Oro/química , Nanopartículas del Metal/uso terapéutico , Nanopartículas del Metal/química , Fototerapia , Polímeros/químicaRESUMEN
OBJECTIVE: Provide a description of clinical characteristics, associated factors and outcome of tracheostomies performed in COVID-19 patients. METHOD: Observational prospective study of 14 patients who underwent tracheostomy. 10 of them were diagnosed with COVID 19, confirmed with RT-PCR test of nasopharyngeal exudate and compatible tomographic findings. RESULTS: Of the 10 patients, five were discharged and five died. The average age of patients who died was 66.6 years; of those who were discharged, it was 60.4 years. Ventilatory parameters cut was taken as FiO2 ≤ 40% and PEEP ≤ 8; of the patients discharged, four met both criteria. On the other hand, of the patients who died, neither met both. Of the latter, an average of APACHE II of 16.4 and SOFA 7.4 were documented, while in discharged patients an average of 12.6 and 4.6 were observed, respectively. CONCLUSIONS: Tracheostomy performed in patients with specific criteria, such as low ventilatory parameters, age, or low score in severity scales, may have a better prognosis.
OBJETIVO: Realizar una descripción de las características clínicas, los factores asociados y el desenlace de las traqueostomías realizadas en pacientes con COVID-19. MÉTODO: Estudio retrospectivo observacional de 14 pacientes a quienes se realizó traqueostomía. Diez de ellos se encontraban diagnosticados con COVID-19, confirmada con prueba RT-PCR de exudado nasofaríngeo y hallazgos tomográficos compatibles. RESULTADOS: De los 10 pacientes, cinco fueron dados de alta y cinco fallecieron. La edad promedio de los pacientes que fallecieron fue de 66.6 años, y la de los que fueron dados de alta fue de 60.4 años. De los parámetros ventilatorios, se tomó como corte una FiO2 ≤ 40% y una PEEP ≤ 8; entre los pacientes dados de alta, cuatro cumplían con ambos criterios. En cambio, de los pacientes que fallecieron, ninguno los cumplió. En estos últimos se documentó un promedio de APACHE II de 16.4 y un SOFA de 7.4, mientras que en los pacientes dados de alta se observó un promedio de 12.6 y 4.6, respectivamente. CONCLUSIONES: La traqueostomía realizada en pacientes con criterios específicos, como parámetros ventilatorios bajos, edad o puntuación baja en las escalas de gravedad, pueden llegar a tener mejor pronóstico.
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COVID-19 , Anciano , Humanos , Hospitales , México/epidemiología , Pronóstico , Estudios Prospectivos , TraqueostomíaRESUMEN
Using the SILAR method Zinc sulfide coatings were deposited on glass slices. The physical properties and the chemical mechanism throughout the variation in concentration of tri-sodium citrate (TSC) as a chelating agent in the synthesis of thin films were investigated. Results shows that ZnS thin films exhibit an average transmittance of 16% in visible light spectra region and a zinc blende structure. The ZnS films synthesized using TSC as a complexing agent, present a smaller average particle size, an average transmittance of 85%, and an adsorption edge at 300-340 nm. Based on our experimental data and analysis, we conclude that the contribution of the oxychloride species, a subproduct in the chemical deposition, is suggested to be related as an impurity level former in the synthesis of ZnS thin films. TSC as a complexing agent in the SILAR technique is a non-toxic option to reduce the generation of the oxychloride species and synthesize a wide band gap semiconductor. Moreover, the use of complexing agents could be extended to other types of semiconductors deposited by SILAR.
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BACKGROUND: In patients with end-stage renal disease, successful renal allotransplantation improves the quality of life and increases survival as compared with long-term dialysis treatment. OBJECTIVE: To show our experience, effectiveness and results of renal transplantations at the University Hospital of UANL. MATERIAL AND METHODS: A retrospective study of renal transplantation performed at University Hospital of UANL was done. The transplant cases from 1967 to July 2001 and January 2003 to June 2011 were included. RESULTS: 280 kidney transplants were performed in 264 patients, 146 men and 118 women; 201 from deceased donor and 79 from living donor. The patient survival at 1, 3, and 5 years was 98.8, 85.9 and 85.9%, respectively. The graft survival at 1, 3, and 5 years, censored for death with functioning graft, was 98.8, 85.7 and 74.9%, respectively. CONCLUSIONS: Our results, in this population with unfavorable socioeconomic conditions, are comparable to those obtained in other institutions.
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Trasplante de Riñón/estadística & datos numéricos , Adolescente , Adulto , Niño , Femenino , Hospitales Universitarios , Humanos , Estudios Longitudinales , Masculino , México , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
AIM: To develop a device to aid in insertion and removal of dentures in patients with limited range of motion. CASE REPORT: A 62-year-old male with congenital musculoskeletal system anomaly, severe scoliosis, missing teeth, and poor dentition presented for comprehensive dental care. Patient had significant range of motion limitations resulting in an inability to reach his mouth. A device allowing for independent insertion, removal, and cleaning of dentures was made for patient. Dentures were fabricated and scanned using an intraoral scanner, traditional surgical guide for implant placement was adapted to accommodate neodynium magnets and wooden dowel, and guide was 3D printed. Stainless steel spheres were processed into denture to correspond to magnets in guide. Patient demonstrated ability to independently insert and remove both his maxillary complete denture and mandibular partial denture using device. CONCLUSION: A successful device for insertion and removal of complete and partial dentures can be fabricated by adapting a surgical guide to incorporate magnets by processing stainless steel spheres into the dentures. This device could be helpful for any individuals demonstrating musculoskeletal system anomalies or range of motion deficits.
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Dentadura Completa , Mandíbula , Humanos , Masculino , Maxilar , Persona de Mediana Edad , Rango del Movimiento ArticularRESUMEN
Fungal peritonitis (FP) is a rare complication of peritoneal dialysis (PD). Candida tropicalis infections are rarely reported in literature. The authors present the first case of FP with peritoneal abscess due to C. tropicalis in a 22-year-old woman admitted to our hospital with septic shock. Abdominal tomography demonstrated an abscess in peritoneal space and intraluminal bubble appearance in femoral venous and arterial circulation. PD fluid specimens and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis revealed fungus growth of C. tropicalis. Fluconazole therapy was administered accompanied by catheter removal and mechanical ventilation with vasopressor support. The patient recovered after 23 days of hospitalization and was discharged. FP represents high mobility and mortality unless infection source control and appropriate antimicrobial therapy are implemented accompanied by PD catheter removal. The use of MALDI-TOF MS for PD-related peritonitis pathogen identification can promote early identification and appropriate antibiotic therapy, especially in C. tropicalis infection.
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Candida tropicalis , Candidiasis/diagnóstico , Diálisis Peritoneal , Peritonitis/diagnóstico , Femenino , Humanos , Peritonitis/microbiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Adulto JovenRESUMEN
Conversion of clean solar energy to chemical fuels is one of the promising and up-and-coming applications of metal-organic frameworks. However, fast recombination of photogenerated charge carriers in these frameworks remains the most significant limitation for their photocatalytic application. Although the construction of homojunctions is a promising solution, it remains very challenging to synthesize them. Herein, we report a well-defined hierarchical homojunction based on metal-organic frameworks via a facile one-pot synthesis route directed by hollow transition metal nanoparticles. The homojunction is enabled by two concentric stacked nanoplates with slightly different crystal phases. The enhanced charge separation in the homojunction was visualized by in-situ surface photovoltage microscopy. Moreover, the as-prepared nanostacks displayed a visible-light-driven carbon dioxide reduction with very high carbon monooxide selectivity, and excellent stability. Our work provides a powerful platform to synthesize capable metal-organic framework complexes and sheds light on the hierarchical structure-function relationships of metal-organic frameworks.
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INTRODUCTION: Idiopathic nodular glomerulosclerosis (ING) is a condition that has a vasculopathic glomerular histological pattern. CASE PRESENTATION: The authors present the case of a 44-year-old Hispanic smoker female with hypertension and peripheral arterial disease who presented nephrotic syndrome for 2 weeks. The patient was diagnosed with ING by percutaneous renal biopsy results, which showed global nodular mesangial matrix expansion, with linear staining accentuation of glomerular and tubular basement membrane for Immunoglobulin G (IgG) and albumin on immunofluorescence. CONCLUSIONS: ING is a rare disease with a poor renal prognosis and wide diagnostic approach; we highlight the importance of analyzing every piece of detail together to reach a definitive diagnosis.
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Nefropatías Diabéticas , Hipertensión , Síndrome Nefrótico , Adulto , Nefropatías Diabéticas/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , RiñónRESUMEN
Oregano essential oils from Lippia berlandieri Schauer (Lb) and Poliomintha longiflora Gray (Pl) were tested against the antioxidant butylated hydroxytoluene (Bht) to evaluate effects on the shelf life of ground beef (GB) over 7 days of storage at 4°C. The treatments were GB1 = GB control, GB2 = GB +100 mg/kg of Bht, GB3 = GB +100 mg/kg of Lb, and GB4 = GB +100 mg/kg of Pl. Lightness, redness, hardness, and springiness showed differences (p < .05) between treatments and days interaction, which serve as indicators of ground beef preserved quality and consumer acceptance. Mesophilic, psychrophilic, and lactic acid bacteria numbers and antioxidant activity showed differences (p < .05) for treatments and days. Sensory attributes showed no differences between treatments. The oregano oils may provide extended shelf life for packaged meat products treated with these natural additives and hence may be used for ground beef preservation.
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The structural details of nanoparticles at the sub-particle level are critical for our understanding of their functionalities and the basic mechanisms involved in their formation. In particular, the geometries of such features determine the particle's overall optical response. Hollow metallic nanoparticles (hollow-MNPs) that have cubic geometries, with varying morphologies on their walls and voids in their body, offer a platform to study the effects of such structural features on the properties of single nanoparticles and their ensemble. Here, we report the control over sub-particle pinholes and voids by modifying the dynamics of the galvanic reaction, and we connect these structures to the optical response of the hollow nanocubes. We observe that symmetry breakage in individual particles, caused by pinholes and voids, has a drastic effect on the plasmon-resonance peak positions in their UV-Vis-NIR spectra. Via electron microscopy imaging, statistical analyses, and electromagnetic simulations, we observe that enlargement in a pinhole's diameter and an increase in their number produce a redshift in the resonance absorption peak of the ensemble. Our results outline nanoparticle design avenues via sub-particle morphologies for several applications, including those operating in the biological window and those carrying chemical payloads in organisms.
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The clinical manifestations of oral cancer and the effects of treatment can have a negative impact on a patient's quality of life. Physiologic functions, cosmetic appearance, and psychological well-being can become compromised during the diagnosis, treatment, and survivorship of patients with oral cancer. This article addresses the relationship of oral cancer and quality of life, as well as the different aspects affected by this condition.