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1.
Sleep Breath ; 27(6): 2257-2263, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37103682

RESUMEN

BACKGROUND: Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing in cerebrovascular diseases, requiring a multidisciplinary approach. There are few studies evaluating the effects of inspiratory muscle training (IMT) in individuals with OSA and the findings regarding the possible effect on apnea hypopnea index (AHI) reduction are controversial. OBJECTIVE: This protocol for a randomized clinical trial will assess the effects of IMT on the severity of obstructive sleep apnea, sleep quality, and daytime sleepiness in individuals after stroke participating in a rehabilitation program. METHODS: This study will be a randomized controlled trial with blinded assessors. Forty individuals after stroke will randomized to two groups. For 5 weeks, both groups will participate in the rehabilitation program activities, including aerobic exercise, resistance training, and educational class when they will receive guidance on the behavioral management of OSA. The experimental group will also perform high-intensity IMT 5 times a week, for 5 weeks, consisting initially of five sets of five repetitions achieving 75% of the maximal inspiratory pressure, increasing one set each week, totaling nine sets at the end of training. The primary outcome will be the severity of OSA measured as AHI at 5 weeks. Secondary outcomes will include sleep quality measured by the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness measured by Epworth Sleepiness Scale (ESS). Outcomes will be collected by a researcher blinded to group allocation at baseline (week 0), after intervention (week 5), and 1 month beyond intervention (week 9). TRIAL REGISTRATION: Clinical Trials Register: NCT05135494.


Asunto(s)
Trastornos de Somnolencia Excesiva , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Accidente Cerebrovascular , Humanos , Apnea Obstructiva del Sueño/terapia , Accidente Cerebrovascular/complicaciones , Músculos , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Exp Parasitol ; 221: 108061, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33383023

RESUMEN

Chagas disease (CD) caused by Trypanosoma cruzi remains a serious public health problem in Latin America. The available treatment is limited to two old drugs, benznidazole (Bz) and nifurtimox, which exhibit limited efficacy and trigger side effects, justifying the search for new therapies. Also, more accurate and sensitive experimental protocols for drug discovery programs are necessary to shrink the translational gaps found among pre-clinical and clinical trials. Presently, cardiac spheroids were used to evaluate host cell cytotoxicity and anti-T.cruzi activity of benznidazole, exploring its effect on the release of inflammatory mediators. Bz presented low toxic profile on 3D matrices (LC50 > 200 µM) and high potency in vitro (EC50 = 0.99 µM) evidenced by qPCR analysis of T.cruzi-infected cardiac spheroids. Flow cytometry appraisal of inflammatory mediators released at the cellular supernatant showed increases in IL - 6 and TNF contents (≈190 and ≈ 25-fold) in parasitized spheroids as compared to uninfected cultures. Bz at 10 µM suppressed parasite load (92%) concomitantly decreasing in IL-6 (36%) and TNF (68%). Our findings corroborate the successful use of 3D cardiac matrices for in vitro identification of novel anti-parasitic agents and potential impact in host cell physiology.


Asunto(s)
Nitroimidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Imagenología Tridimensional , Ratones , Microscopía Fluorescente , Conformación Molecular , Esferoides Celulares , Trypanosoma cruzi/crecimiento & desarrollo
3.
Parasitology ; 147(2): 240-247, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31603062

RESUMEN

Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.


Asunto(s)
Antígenos Helmínticos/inmunología , Inmunoglobulinas/sangre , Pruebas Inmunológicas/métodos , Neurocisticercosis/parasitología , Taenia/aislamiento & purificación , Animales , Afinidad de Anticuerpos , Pollos , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Neurocisticercosis/inmunología , Óvulo , Taenia/inmunología
4.
Int J Med Microbiol ; 309(3-4): 169-181, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30799091

RESUMEN

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD), a Lancefield group C streptococci (GCS), is a frequent cause of bovine mastitis. This highly prevalent disease is the costliest in dairy industry. Adherence and biofilm production are important factors in streptoccocal pathogenesis. We have previously described the adhesion and internalization of SDSD isolates in human cells and now we describe the biofilm production capability of this bacterium. In this work we integrated microbiology, imaging and computational methods to evaluate the biofilm production capability of SDSD isolates; to assess the presence of biofilm regulatory protein BrpA homolog in the biofilm producers; and to predict a structural model of BrpA-like protein and its binding to putative inhibitors. Our results show that SDSD isolates form biofilms on abiotic surface such as glass (hydrophilic) and polystyrene (hydrophobic), with the strongest biofilm formation observed in glass. This ability was mainly associated with a proteinaceous extracellular matrix, confirmed by the dispersion of the biofilms after proteinase K and trypsin treatment. The biofilm formation in SDSD isolates was also confirmed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Under SEM observation, VSD16 isolate formed cell aggregates during biofilm growth while VSD9 and VSD10 formed smooth and filmy layers. We show that brpA-like gene is present and expressed in SDSD biofilm-producing isolates and its expression levels correlated with the biofilm production capability, being more expressed in the late exponential phase of planktonic growth compared to biofilm growth. Fisetin, a known biofilm inhibitor and a putative BrpA binding molecule, dramatically inhibited biofilm formation by the SDSD isolates but did not affect planktonic growth, at the tested concentrations. Homology modeling was used to predict the 3D structure of BrpA-like protein. Using high throughput virtual screening and molecular docking, we selected five ligand molecules with strong binding affinity to the hydrophobic cleft of the protein, making them potential inhibitor candidates of the SDSD BrpA-like protein. These results warrant further investigations for developing novel strategies for SDSD anti-biofilm therapy.


Asunto(s)
Antibacterianos/química , Proteínas Bacterianas/antagonistas & inhibidores , Biopelículas/crecimiento & desarrollo , Streptococcus/fisiología , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Matriz Extracelular de Sustancias Poliméricas/química , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Matriz Extracelular de Sustancias Poliméricas/ultraestructura , Femenino , Flavonoides/química , Flavonoides/farmacología , Flavonoles , Expresión Génica , Regulación Bacteriana de la Expresión Génica , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Conformación Proteica , Infecciones Estreptocócicas/microbiología , Streptococcus/efectos de los fármacos , Streptococcus/genética , Streptococcus/metabolismo
5.
Parasitol Res ; 118(5): 1657-1660, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30877437

RESUMEN

Herein, we evaluate a mimotope-based synthetic peptidenamed NC41 to diagnose neurocysticercosis (NC), a neglected parasitic disease and a major cause of epilepsy worldwide. NC41 synthetic peptide was evaluated to diagnose NC, and total saline extract from Taenia solium metacestodes (SE) was used as control. Serum samples from patients with NC (n = 40), other parasitic diseases (n = 43), and healthy individuals (n = 40) were tested. Diagnostic parameters such as sensitivity (Se), specificity (Sp), likelihood ratio (LR), and area under curve (AUC) were calculated using receiver operating characteristic (ROC) curves. The sequence from T. solium phosphoenolpyruvate carboxykinase (PEPCK) was used for epitope prediction, resulting in one high-scoring patch centered at residue L247. NC41 synthetic peptide reached high diagnostic performance (Se 97.5% and Sp 97.5%, LR+ 39 and AUC 0.997). Data from diagnostic parameters and in silico analyses proved the usefulness of NC41 synthetic peptide as a diagnostic marker for human NC.


Asunto(s)
Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/sangre , Neurocisticercosis/diagnóstico , Péptidos/inmunología , Fosfoenolpiruvato Carboxiquinasa (ATP)/inmunología , Taenia solium/aislamiento & purificación , Animales , Área Bajo la Curva , Biomarcadores , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Neurocisticercosis/sangre , Neurocisticercosis/parasitología , Péptidos/genética , Fosfoenolpiruvato Carboxiquinasa (ATP)/genética , Sensibilidad y Especificidad , Taenia solium/inmunología
6.
Blood Cells Mol Dis ; 55(3): 236-40, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26227853

RESUMEN

Some myeloproliferative neoplasm (MPN) patients harbor JAK2(V617F) mutation, and CALR mutations were recently discovered in wild type (WT) JAK2(V617F). We evaluated the frequency and type of CALR mutations, and clinical and hematological characteristics in WT JAK2(V617F) and MPL(W515K/L) MPN patients. Sixty-five patients were included: 21 with primary myelofibrosis (PMF), 21 with myelofibrosis post-essential thrombocythemia (MPET) and 23 with essential thrombocythemia (ET). Screening for JAK2(V617F) and MPL(W515K/L) were performed using real-time PCR, while CALR mutations were analyzed by fragment analysis and Sanger sequencing. JAK2(V617F) was the most frequent mutation (54.5%) and one patient (1.5%) harbored MPL(W515L). CALR mutations were present in 38.1% of PMF, 12.5% of ET and 33.3% of MPET patients. Five types of CALR mutations were detected, among which type 1 (32.1%) and type 2 (21.4%) were found to be the most common. A novel CALR mutation in a PMF patient was found. Patients carrying CALR mutations had higher platelet count and less presence of splenomegaly than JAK2(V617F), while triple negatives had higher C-reactive protein levels than CALR mutant carriers. Screening for CALR mutations and its correlation with clinical features could be useful for the characterization of MPN patients and result in its incorporation into a new prognostic score.


Asunto(s)
Janus Quinasa 2/genética , Mutación , Trastornos Mieloproliferativos/metabolismo , Brasil , Calreticulina/metabolismo , Humanos , Janus Quinasa 2/metabolismo , Tasa de Mutación , Trastornos Mieloproliferativos/genética , Recuento de Plaquetas , Reacción en Cadena en Tiempo Real de la Polimerasa , Trombopoyetina/metabolismo
7.
Microsc Microanal ; 21(1): 108-19, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25331195

RESUMEN

The present work reports a simple and easy wet chemistry synthesis of cuprous oxide (Cu2O) nanospheres at room temperature without surfactants and using different precursors. Structural characterization was carried out by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy coupled with focused ion beam and energy-dispersive X-ray spectroscopy. The optical band gaps were determined from diffuse reflectance spectroscopy. The photoluminescence behavior of the as-synthesized nanospheres showed significant differences depending on the precursors used. The Cu2O nanospheres were constituted by aggregates of nanocrystals, in which an on/off emission behavior of each individual nanocrystal was identified during transmission electron microscopy observations. The thermal behavior of the Cu2O nanospheres was investigated with in situ X-ray diffraction and differential scanning calorimetry experiments. Remarkable structural differences were observed for the nanospheres annealed in air, which turned into hollow spherical structures surrounded by outsized nanocrystals.

8.
Nanotechnology ; 25(41): 415202, 2014 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-25257959

RESUMEN

This work reports on highly efficient surface enhanced Raman spectroscopy (SERS) constructed on low-cost, fully recyclable and highly reproducible cardboard plates, which are commonly used as disposable packaging material. The active optical component is based on plasmonic silver nanoparticle structures separated from the metal surface of the cardboard by a nanoscale dielectric gap. The SERS response of the silver (Ag) nanoparticles of various shapes and sizes were systematically investigated, and a Raman enhancement factor higher than 106 for rhodamine 6G detection was achieved. The spectral matching of the plasmonic resonance for maximum Raman enhancement with the optimal local electric field enhancement produced by 60 nm-sized Ag NPs predicted by the electromagnetic simulations reinforces the outstanding results achieved. Furthermore, the nanoplasmonic SERS substrate exhibited high reproducibility and stability. The SERS signals showed that the intensity variation was less than 5%, and the SERS performance could be maintained for up to at least 6 months.

9.
Parasitol Res ; 113(7): 2569-75, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24777340

RESUMEN

Neurocysticercosis (NC) is one of the most important diseases caused by parasites affecting the central nervous system. We fractionated by ion-exchange chromatography using diethylaminoethyl (DEAE)-sepharose resin the total saline extract (S) from Taenia solium metacestodes and evaluated obtained fractions (DEAE S1 and DEAE S2) by enzyme-linked immunosorbent assay (ELISA, n = 123) and immunoblotting (IB, n = 22) to detect human NC in serum. Diagnostic parameters were established by ROC and TG ROC curves for ELISA tests. IB was qualitatively analyzed. S and DEAE S1 presented sensitivity of 87. 5% and DEAE S2 90%. The best specificity was observed for DEAE S2 (90.4%). In IB, using DEAE S2 samples from NC patients presented bands of 20-25, 43-45, 55-50, 60-66, 82, 89, and 140 kDa. The great diagnostic parameters reached by DEAE S2 suggest the potential applicability of this fraction in NC immunodiagnosis.


Asunto(s)
Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/aislamiento & purificación , Etanolaminas/química , Inmunoglobulina G/sangre , Neurocisticercosis/diagnóstico , Taenia solium/inmunología , Animales , Antígenos Helmínticos/inmunología , Fraccionamiento Químico , Cromatografía por Intercambio Iónico , Ensayo de Inmunoadsorción Enzimática , Humanos , Immunoblotting , Neurocisticercosis/sangre , Neurocisticercosis/inmunología , Sensibilidad y Especificidad , Pruebas Serológicas , Porcinos , Taenia solium/aislamiento & purificación
10.
Int J Pharm ; 650: 123659, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38042383

RESUMEN

Among the unique characteristics associated to gold nanoparticles (AuNPs) in biomedicine, their ability to convert light energy into heat opens ventures for improved cancer therapeutic options, such as photothermal therapy (PTT). PTT relies on the local hyperthermia of tumor cells upon irradiation with light beams, and the association of AuNPs with radiation within the near infrared (NIR) range constitutes an advantageous strategy to potentially improve PTT efficacy. Herein, it was explored the effect of the gold salt on the AuNPs' physicochemical and optical properties. Mostly spherical-like negatively charged AuNPs with variable sizes and absorbance spectra were obtained. In addition, photothermal features were assessed using in vitro phantom models. The best formulation showed the ability to increase their temperature in aqueous solution up to 19 °C when irradiated with a NIR laser for 20 min. Moreover, scanning transmission electron microscopy confirmed the rearrangement of the gold atoms in a face-centered cubic structure, which further allowed to calculate the photothermal conversion efficiency upon combination of theoretical and experimental data. AuNPs also showed local retention after being locally administered in in vivo models. These last results obtained by computerized tomography allow to consider these AuNPs as promising elements for a PTT system. Moreover, AuNPs showed high potential for PTT by resulting in in vitro cancer cells' viability reductions superior to 70 % once combine with 5 min of NIR irradiation.


Asunto(s)
Oro , Nanopartículas del Metal , Oro/química , Fototerapia , Terapia Fototérmica , Nanopartículas del Metal/química , Línea Celular Tumoral
11.
Biomed Pharmacother ; 175: 116742, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754265

RESUMEN

Chagasic chronic cardiomyopathy (CCC) is the primary clinical manifestation of Chagas disease (CD), caused by Trypanosoma cruzi. Current therapeutic options for CD are limited to benznidazole (Bz) and nifurtimox. Amiodarone (AMD) has emerged as most effective drug for treating the arrhythmic form of CCC. To address the effects of Bz and AMD we used a preclinical model of CCC. Female C57BL/6 mice were infected with T. cruzi and subjected to oral treatment for 30 consecutive days, either as monotherapy or in combination. AMD in monotherapy decreased the prolonged QTc interval, the incidence of atrioventricular conduction disorders and cardiac hypertrophy. However, AMD monotherapy did not impact parasitemia, parasite load, TNF concentration and production of reactive oxygen species (ROS) in cardiac tissue. Alike Bz therapy, the combination of Bz and AMD (Bz/AMD), improved cardiac electric abnormalities detected T. cruzi-infected mice such as decrease in heart rates, enlargement of PR and QTc intervals and increased incidence of atrioventricular block and sinus arrhythmia. Further, Bz/AMD therapy ameliorated the ventricular function and reduced parasite burden in the cardiac tissue and parasitemia to a degree comparable to Bz monotherapy. Importantly, Bz/AMD treatment efficiently reduced TNF concentration in the cardiac tissue and plasma and had beneficial effects on immunological abnormalities. Moreover, in the cardiac tissue Bz/AMD therapy reduced fibronectin and collagen deposition, mitochondrial damage and production of ROS, and improved sarcomeric and gap junction integrity. Our study underlines the potential of the Bz/AMD therapy, as we have shown that combination increased efficacy in the treatment of CCC.


Asunto(s)
Amiodarona , Cardiomiopatía Chagásica , Modelos Animales de Enfermedad , Quimioterapia Combinada , Ratones Endogámicos C57BL , Nitroimidazoles , Tripanocidas , Trypanosoma cruzi , Animales , Nitroimidazoles/farmacología , Nitroimidazoles/administración & dosificación , Nitroimidazoles/uso terapéutico , Femenino , Trypanosoma cruzi/efectos de los fármacos , Amiodarona/farmacología , Amiodarona/administración & dosificación , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/parasitología , Tripanocidas/farmacología , Tripanocidas/uso terapéutico , Ratones , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Especies Reactivas de Oxígeno/metabolismo , Enfermedad Crónica , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , Factor de Necrosis Tumoral alfa/metabolismo , Carga de Parásitos
12.
Trop Med Int Health ; 18(10): 1180-92, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23906320

RESUMEN

OBJECTIVE: To evaluate the potential involvement of anti-Trypanosoma cruzi and cardiac protein antibody (IgG total and isotypes) production and their possible association with different clinical forms of human chronic Chagas disease. METHODS: IgG total and isotypes were measured by ELISA, using epimastigote and trypomastigote forms of T. cruzi as antigens and human cardiac proteins (myosin and troponin T) in sera of patients with indeterminate (IND, n = 72), cardiac (CARD, n = 47) and digestive/cardiodigestive (DIG/CARD-DIG, n = 12) clinical forms of the disease. Samples from uninfected health individuals (CONT, n = 30) and patients with ischaemic cardiomyopathy (ISCH, n = 15) were used as controls. Autoantibody levels were correlated with parameters of cardiac function obtained by electrocardiographic, radiographic and echocardiographic examinations. RESULTS: Fifty five per cent of patients were classified as IND, 35.9% as CARD and 9.1% as DIG/CARD-DIG. Greater total IgG production was observed in IND, CARD and DIG/CARD-DIG chagasic patients than in CONT and ISCH, using trypomastigote, epimastigote and cardiac antigens. Moreover, patients with CARD and DIG/CARD-DIG presented greater total IgG production (trypomastigote and epimastigote antigen) than IND, and a negative correlation was determined between total IgG and left ventricular ejection fraction (LVEF). Patients with IND and CARD presented similar higher levels of total IgG specific to troponin T and myosin than CONT and ISCH individuals. Patients with chronic Chagas disease presented a negative correlation between left ventricular ejection fraction (LVEF) and the production of anti-myosin and troponin T autoantibodies. When grouped as low and high antibody producers and compared with LVEF, we observed that high anti-troponin T (P = 0.042) and myosin (P = 0.013) producers presented lower LVEF than low producers. Moreover, there was a positive correlation (r = 0.9508, P = 0.0001) between the production of troponin T and myosin autoantibodies. CONCLUSION: These findings indicate that increased production of anti-cardiac troponin T and myosin autoantibodies probably influences the left ventricular ejection fraction and could be related to chagasic cardiomyopathy.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Autoanticuerpos/sangre , Cardiomiopatía Chagásica/inmunología , Troponina T/inmunología , Trypanosoma cruzi/inmunología , Adulto , Anciano , Antígenos de Protozoos/inmunología , Estudios de Casos y Controles , Cardiomiopatía Chagásica/complicaciones , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Miosinas/inmunología , Salud Rural , Adulto Joven
13.
Microsc Microanal ; 19(5): 1211-5, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23764134

RESUMEN

Nd:11Fe:Ti alloys prepared by arc melting followed by splat quenching and annealing have been investigated by electron microscopy. The as-cast microstructure evidenced an α-Fe(Ti) --> NdFe11Ti --> Nd2(Fe,Ti)17 solidification sequence compatible with a cascade of peritectic reactions. The Nd2(Fe,Ti)17 phase was not detected in the microstructure of the splat-quenched materials, but after annealing the ternary compound grains consisted of a mixture of ThMn12-type and Th2Zn17-type structures exhibiting a consistent (020)1:12//(003)2:17 and [100]1:12//[110]2:17, orientation relation, with the invariant plane sitting at (022)1:12//(333)2:17. A series of 3D microdiffraction experiments carried out on grains presenting a random distribution of planar defects has been used to map the reciprocal space of the intergrown phases.

14.
Nanomaterials (Basel) ; 13(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36985984

RESUMEN

The preparation of visible-light-driven photocatalysts has become highly appealing for environmental remediation through simple, fast and green chemical methods. The current study reports the synthesis and characterization of graphitic carbon nitride/titanium dioxide (g-C3N4/TiO2) heterostructures through a fast (1 h) and simple microwave-assisted approach. Different g-C3N4 amounts mixed with TiO2 (15, 30 and 45 wt. %) were investigated for the photocatalytic degradation of a recalcitrant azo dye (methyl orange (MO)) under solar simulating light. X-ray diffraction (XRD) revealed the anatase TiO2 phase for the pure material and all heterostructures produced. Scanning electron microscopy (SEM) showed that by increasing the amount of g-C3N4 in the synthesis, large TiO2 aggregates composed of irregularly shaped particles were disintegrated and resulted in smaller ones, composing a film that covered the g-C3N4 nanosheets. Scanning transmission electron microscopy (STEM) analyses confirmed the existence of an effective interface between a g-C3N4 nanosheet and a TiO2 nanocrystal. X-ray photoelectron spectroscopy (XPS) evidenced no chemical alterations to both g-C3N4 and TiO2 at the heterostructure. The visible-light absorption shift was indicated by the red shift in the absorption onset through the ultraviolet-visible (UV-VIS) absorption spectra. The 30 wt. % of g-C3N4/TiO2 heterostructure showed the best photocatalytic performance, with a MO dye degradation of 85% in 4 h, corresponding to an enhanced efficiency of almost 2 and 10 times greater than that of pure TiO2 and g-C3N4 nanosheets, respectively. Superoxide radical species were found to be the most active radical species in the MO photodegradation process. The creation of a type-II heterostructure is highly suggested due to the negligible participation of hydroxyl radical species in the photodegradation process. The superior photocatalytic activity was attributed to the synergy of g-C3N4 and TiO2 materials.

15.
Vaccine X ; 14: 100333, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37362023

RESUMEN

The COVID-19 pandemic has significantly impacted global health, and the widespread immunization of adults against SARS-CoV-2 has played a pivotal role in altering the course of the disease. While COVID-19 vaccine adverse events are generally uncommon and mild, the recent vaccination of the pediatric population has emphasized the need for vigilance and reporting of potential side effects. In this case report, we present a 6-year-old boy who developed Henoch-Schönlein purpura following the administration of the first dose of Pfizer-BioNTech BNT16B2b2 mRNA COVID-19 vaccine, making it the earliest reported case of such an adverse event. Our report highlights the importance of continued monitoring and reporting of adverse events in pediatric patients receiving the COVID-19 vaccine, as well as the need for prompt diagnosis and management of potential vaccine-related complications.

16.
Nanomaterials (Basel) ; 12(6)2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35335818

RESUMEN

In this study, polyethylene glycol-modified titanium dioxide (PEG-modified TiO2) nanopowders were prepared using a fast solvothermal method under microwave irradiation, and without any further calcination processes. These nanopowders were further impregnated on porous polymeric platforms by drop-casting. The effect of adding iron with different molar ratios (1, 2, and 5%) of iron precursor was investigated. The characterization of the produced materials was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Optical characterization of all the materials was also carried out. SEM showed that pure TiO2 and Fe-TiO2 nanostructures presented similar nanosized and spherical particles, which uniformly covered the substrates. From XRD, pure TiO2 anatase was obtained for all nanopowders produced, which was further confirmed by Raman spectroscopy on the impregnated substrates. XPS and UV-VIS absorption spectroscopy emission spectra revealed that the presence of Fe ions on the Fe-TiO2 nanostructures led to the introduction of new intermediate energy levels, as well as defects that contributed to an enhancement in the photocatalytic performance. The photocatalytic results under solar radiation demonstrated increased photocatalytic activity in the presence of the 5% Fe-TiO2 nanostructures (Rhodamine B degradation of 85% after 3.5 h, compared to 74% with pure TiO2 for the same exposure time). The photodegradation rate of RhB dye with the Fe-TiO2 substrate was 1.5-times faster than pure TiO2. Reusability tests were also performed. The approach developed in this work originated novel functionalized photocatalytic platforms, which were revealed to be promising for the removal of organic dyes from wastewater.

17.
Dement Neuropsychol ; 15(3): 413-418, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34630931

RESUMEN

Rasmussen encephalitis is a rare disease consisting of a chronic, slowly progressive inflammatory reaction of brain tissues. The objective of this study was to describe the case of an 18-year-old female patient, studying on the fourth grade of elementary school, and right-handed, who underwent left hemispherectomy in a neurological rehabilitation program. Her seizures began at 10 years of age and were unresponsive to drug treatment, with functional repercussions. She underwent hemispherectomy in March 2019, with 7 years of ongoing disease, and was admitted for the rehabilitation program with a multidisciplinary team in June 2020. The quality-of-life questionnaire (WHOQOL-BREF) was applied as a comparison measure before and after the rehabilitation program, along with measures of participation on the program activities. Despite the patient's short time in a rehabilitation program, data show the importance of an interdisciplinary intervention through the establishment of specific and contextualized objectives in chronic patients.


A encefalite de Rasmussen representa uma doença rara, que consiste em uma reação inflamatória dos tecidos cerebrais, de modo crônico e lentamente progressivo. O objetivo deste estudo foi descrever o caso de uma paciente, submetida à hemisferectomia à esquerda, em março de 2019, em programa de reabilitação neurológica. Paciente do sexo feminino, 18 anos de idade, 4ª série do ensino fundamental, destra, que participou de programa de reabilitação neurológica interdisciplinar após hemisferectomia. Início das crises convulsivas aos 10 anos de idade, refratárias ao tratamento medicamentoso, com repercussão funcional. Foi submetida à hemisferectomia em março de 2019, com sete anos de doença em curso. Foi internada para programa de reabilitação, com equipe multiprofissional, em junho de 2020. Aplicou-se o questionário de qualidade de vida (WHOQOL-BREF), como medida de comparação antes e após o programa de reabilitação, além de medidas de participação nas atividades do programa. Os dados, apesar do pouco tempo da paciente em programa de reabilitação, mostram a importância da intervenção interdisciplinar, por meio do estabelecimento de objetivos realísticos e contextualizados.

18.
Materials (Basel) ; 14(9)2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-34064309

RESUMEN

The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min-1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight.

19.
ChemMedChem ; 16(14): 2231-2253, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-33856742

RESUMEN

Chagas disease is a tropical infectious disease resulting in progressive organ-damage and currently lacks efficient treatment and vaccine options. The causative pathogen, Trypanosoma cruzi, requires uptake and processing of preformed purines from the host because it cannot synthesize these de novo, instigating the evaluation of modified purine nucleosides as potential trypanocides. By modifying the pyrimidine part of a previously identified 7-aryl-7-deazapurine nucleoside, we found that substitution of a 6-methyl for a 6-amino group allows retaining T. cruzi amastigote growth inhibitory activity but confers improved selectivity towards mammalian cells. By keeping the 6-methyl group unaltered, and introducing different 7-aryl groups, we identified several analogues with sub-micromolar antitrypanosomal activity. The 7-(4-chlorophenyl) analogue 14, which was stable in microsomes, was evaluated in an acute mouse model. Oral administration of 25 mg/kg b.i.d. suppressed peak parasitemia and protected mice from infection-related mortality, gave similar reductions as the reference drug of blood parasite loads determined by qPCR, but as benznidazole failed to induce sterile cure in the short time period of drug exposure (5 days).


Asunto(s)
Nucleósidos/farmacología , Purinas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Estructura Molecular , Nucleósidos/síntesis química , Nucleósidos/química , Pruebas de Sensibilidad Parasitaria , Purinas/síntesis química , Purinas/química , Relación Estructura-Actividad , Tripanocidas/síntesis química , Tripanocidas/química
20.
Korean J Orthod ; 51(6): 387-396, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34803027

RESUMEN

OBJECTIVE: To identify optimal areas for the insertion of extra-alveolar miniscrews into the infrazygomatic crest (IZC) and mandibular buccal shelf (MBS), using cone beam computed tomography (CBCT) imaging in patients with different craniofacial patterns. METHODS: CBCT reconstructions of untreated individuals were used to evaluate the IZC and MBS areas. The participants were divided into three groups, based on the craniofacial pattern, namely, brachyfacial (n = 15; mean age, 23.3 years), mesofacial (n = 15; mean age, 19.24 years), and dolichofacial (n = 15; mean age, 17.79 years). In the IZC, the evaluated areas were at 11, 13, and 15 mm above the buccal cusp tips of the right and left first molars. In the MBS, the evaluated areas were at the projections of the first molars' distal roots and second molars' mesial and distal roots, at a 4- and 8-mm distance from the cementoenamel junction. Intergroup comparisons were performed with analysis of variance and the Tukey test. RESULTS: There was no statistically significant difference in the IZC bone thickness among the groups. For MBS bone availability, some comparisons revealed no difference; meanwhile, other comparisons revealed increased MBS bone thickness in the brachyfacial (first molars distal roots) and dolichofacial (second molars mesial and distal roots) patterns. CONCLUSIONS: There was no significant difference in the IZC bone thickness among the groups. The facial skeletal pattern may affect the availability of ideal bone thickness for the insertion of extra-alveolar miniscrews in the MBS region; however, this variability is unlikely to be clinically meaningful.

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