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1.
Materials (Basel) ; 16(9)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37176470

RESUMO

Oral candidiasis is an opportunistic infection that affects mainly individuals with weakened immune system. Devices used in the oral area to treat this condition include buccal films, which present advantages over both oral tablets and gels. Since candidiasis causes pain, burning, and itching, the purpose of this work was to develop buccal films loaded with both lidocaine (anesthetic) and miconazole nitrate (MN, antifungal) to treat this pathology topically. MN was loaded in microparticles based on different natural polymers, and then, these microparticles were loaded in hydroxypropyl methylcellulose-gelatin-based films containing lidocaine. All developed films showed adequate adhesiveness and thickness. DSC and XRD tests suggested that the drugs were in an amorphous state in the therapeutic systems. Microparticles based on chitosan-alginate showed the highest MN encapsulation. Among the films, those containing the mentioned microparticles presented the highest tensile strength and the lowest elongation at break, possibly due to the strong interactions between both polymers. These films allowed a fast release of lidocaine and a controlled release of MN. Due to the latter, these systems showed antifungal activity for 24 h. Therefore, the treatment of oropharyngeal candidiasis with these films could reduce the number of daily applications with respect to conventional treatments.

2.
Int J Neurosci ; 133(2): 194-200, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33736564

RESUMO

Purpose:Tau hyperphosphorylation is a modification frequently observed after brain ischemia which has been related to the aggregation of this protein, with subsequent cytoskeletal damage, and cellular toxicity. The present study tests the hypothesis of using glucosamine, an agent that increases protein O-GlcNAcylation, to decrease the levels of phosphorylation in Tau during ischemia-reperfusion.Material and methods: Transient focal ischemia was artificially induced in male Wistar rats by occlusion of the middle cerebral artery (MCAO) with an intraluminal monofilament. A single dose of intraperitoneal glucosamine of 200 mg/kg diluted in normal saline (SSN) was administered 60 min before ischemia. Histological brain sections were processed using indirect immunofluorescence with primary antibodies (anti-O-GlcNAc and anti pTau-ser 396). The Image J software was used to calculate the immunofluorescence signal intensity.Results: The phosphorylation of Tau at the serine residue 396 had a significant decrease with the administration of glucosamine during ischemia-reperfusion compared with the administration of placebo.Conclusions: These results show that glucosamine can reduce the phosphorylation levels of Tau in rodents subjected to ischemia and cerebral reperfusion, which implies a neuroprotective role of glucosamine.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Masculino , Glucosamina/farmacologia , Proteínas tau/metabolismo , Fosforilação , Ratos Wistar , Isquemia Encefálica/tratamento farmacológico , Isquemia , Reperfusão , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Fármacos Neuroprotetores/farmacologia
3.
Chem Phys Lipids ; 249: 105252, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36272518

RESUMO

Vitamin E (VitE) is one of the most important antioxidants and plays a key role in decreasing the inflammatory effects of oxidative stress caused by recurrent doses of iron administration in anemia treatment. However, VitE is poorly soluble in aqueous environments. Here, VitE encapsulation into solid lipid nanoparticles (SLN) composed of myristil myristate to improve its bioavailability was proposed. A 99.9 ± 0.1% encapsulation efficiency with a drug/lipid ratio of 500 µg/mg and 478 higher VitE solubility was obtained. The antioxidant properties of VitE after encapsulation were maintained. SLN-VitE showed a 228.2 nm mean diameter with low polidispersitivity (0.335), and negative Z potential (ζ ≈ -9.0 mV). The SLN were well-dispersed, displayed spherical and homogeneous morphology by TEM. A controlled release of VitE from SLN was found. The XRD and FTIR analyses revealed the presence of a nanostructured architecture of SLN after VitE incorporation. We probed the safety of SLN-VitE after contact with three in vitro cell models: erythrocytes, lymphocytes and HepG2 cells. The cell viability in presence of SLN, SLN-VitE, and their combinations with iron was not affected. The comet assay demonstrated that the DNA damage caused by iron administration was decrease in presence of SLN-VitE.


Assuntos
Anemia , Nanopartículas , Humanos , Portadores de Fármacos , Lipídeos , Vitamina E , Tamanho da Partícula , Antioxidantes/farmacologia , Anemia/induzido quimicamente , Anemia/tratamento farmacológico
4.
Front Chem ; 10: 914126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873038

RESUMO

Violacein (Viol) is a bacterial purple water-insoluble pigment synthesized by Chromobacterium violaceum and other microorganisms that display many beneficial therapeutic properties including anticancer activity. Viol was produced, purified in our laboratory, and encapsulated in a nanostructured lipid carrier (NLC). The NLC is composed of the solid lipid myristyl myristate, an oily lipid mixture composed of capric and caprylic acids, and the surfactant poloxamer P188. Dormant lipase from Rhizomucor miehei was incorporated into the NLC-Viol to develop an active release system. The NLC particle size determined by dynamic light scattering brings around 150 nm particle size and ζ≈ -9.0 mV with or without lipase, but the incorporation of lipase increase the PdI from 0.241 to 0.319 (≈32%). For scaffold development, a 2.5 hydroxypropyl methylcellulose/chitosan ratio was obtained after optimization of a composite for extrusion in a 3D-bioprinter developed and constructed in our laboratory. Final Viol encapsulation efficiency in the printings was over 90%. Kinetic release of the biodye at pH = 7.4 from the mesh containing NLC-lipase showed roughly 20% Viol fast release than without the enzyme. However, both Viol kinetic releases displayed similar profiles at pH = 5.0, where the lipase is inactive. The kinetic release of Viol from the NLC-matrices was modeled and the best correlation was found with the Korsmeyer-Peppas model (R2 = 0.95) with n < 0.5 suggesting a Fickian release of Viol from the matrices. Scanning Electron Microscope (SEM) images of the NLC-meshes showed significant differences before and after Viol's release. Also, the presence of lipase dramatically increased the gaps in the interchain mesh. XRD and Fourier Transform Infrared (FTIR) analyses of the NLC-meshes showed a decrease in the crystalline structure of the composites with the incorporation of the NLC, and the decrease of myristyl myristate in the mesh can be attributed to the lipase activity. TGA profiles of the NLC-meshes showed high thermal stability than the individual components. Cytotoxic studies in A549 and HCT-116 cancer cell lines revealed high anticancer activity of the matrix mediated by mucoadhesive chitosan, plus the biological synergistic activities of violacein and lipase.

5.
Braz J Biol ; 84: e257470, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35416853

RESUMO

Lethal yellowing (LY) is a disease that affects coconut and other palm species. It is associated to phytoplasmas of the group 16SrIV and the only reported insect vector for this pathogen so far is Haplaxius crudus. H. crudus is present in Mexico and has been associated to 16SrIV phytoplasmas, however, it was not detectable during a LY outbreak in the coast of Yucatan, Mexico, suggesting the existence of other vector species. To test this hypothesis a survey of insects was carried out and a total of 3074 insects were captured during a year of monthly sampling. Ten taxonomic orders were identified in this sample, Hemiptera being the most abundant (N=2094), and these were classified into nine families. The leafhopper Colpoptera sp. from to the Nogodinidae family was de most abundant representing 56% of the total number of insects sampled and 23% of these samples resulted positive for LY phytoplasma by PCR detection. The BLAST comparison, virtual RFLP and phylogenetic analyses of the sequenced amplicons relate the detected phytoplasma to the subgroup 16SrIV-A. The findings presented herein suggest that Colpoptera sp. could be considered as a new putative vector of the LY-causing phytoplasmas in Mexico and a candidate for further research.


Assuntos
Hemípteros , Phytoplasma , Animais , DNA , Hemípteros/genética , Humanos , México , Filogenia , Phytoplasma/genética , Doenças das Plantas
6.
J Environ Radioact ; 242: 106793, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34923321

RESUMO

The activity concentrations of 40K, 210Pb, 210Po, 226Ra, 228Ra, 228Th, 230Th, 232Th, 234U, and 238U were determined in 82 food samples, grouped into 20 food groups according to the Brazilian Total Diet, which reflects the dietary habits of a population, for the rural and urban areas of Poços de Caldas city, a High Background Radiation Area. The highest activity concentration found in the food samples was due to 40K being present in all types of food. Among the other radionuclides, high activity concentrations were found for 210Pb in beans and salt, 210Po in fish, 226Ra and 228Ra in nuts and seeds. The main food groups that contributed most to the effective dose, in urban and rural regions, were beans and beverages. The effective doses, due to the ingestion of the analysed food groups, were of 0.44 and 0.60 mSv y-1 and the lifetime cancer risks were 1.6 × 10-3 and 2.3 × 10-3 for the urban and rural Poços de Caldas population, respectively.


Assuntos
Radiação de Fundo , Monitoramento de Radiação , Brasil , Dieta , Radioisótopos/análise
7.
Ludovica pediátr ; 24(2): 8-13, dic.2021.
Artigo em Espanhol | LILACS, Redbvs, ARGMSAL, BINACIS | ID: biblio-1363144

RESUMO

Introducción: La coinfección de COVID-19 con otros patógenos respiratorios en pediatría ha sido poco estudiada. Resulta de interés conocer las características y cuadro clínico de pacientes que presenten coinfecciones con COVID-19. Objetivo: Estudiar la coinfección de SARS-CoV-2 con patógenos incluidos en el Panel RP 2.0 FilmArray® en muestras de pacientes pediátricos en un hospital del tercer nivel. Materiales y métodos: Durante abril a agosto de 2021 se realizó un estudio prospectivo descriptivo sobre 21 muestras de Hisopado Nasofaríngeo de pacientes pediátricos positivos para SARS-CoV-2 (iAMP® COVID-19 Detection Kit de Atila Biosystems). Se procesaron por PCR multiplex Filmarray® RP 2.0. Luego se describieron las características y síntomas de los pacientes. Resultados: 12/21 (60%) fueron pacientes ambulatorios y 8/21 (40%) internados. El 57% de los pacientes fueron mayores de 5 años, el 24% menores de 1 año y el 19% entre 1 y 5 años. El síntoma más frecuente fue fiebre 18/21 (86%). El 90,5% (19/21) de las muestras no mostraron detección de otros patógenos. En una muestra se detectó Rhino/enterovirus y en otra Coronavirus NL63; ambas pertenecieron a dos pacientes con enfermedades de base. Conclusión: La tasa de coinfecciones fue del 9,5%. Este número podría deberse a la baja circulación de patógenos respiratorios en un contexto con medidas de prevención de los contagios. En el estado actual de incremento de circulación de virus respiratorios endémicos, es de interés la búsqueda de coinfecciones con COVID-19


Introduction: The co-infection of COVID-19 with other respiratory pathogens in pediatrics has been little studied. It is of interest to know the characteristics and clinical picture of patients who present co-infections with COVID-19. Objective: To study the co-infection of SARS-CoV-2 with pathogens included in the RP Panel 2.0 FilmArray® in samples from pediatric patients in a third-level hospital. Materials and methods: During April to August 2021, a prospective descriptive study was conducted on 21 Nasopharyngeal Swab samples from pediatrics patients positive for SARS-CoV-2 (iAMP® COVID-19 Detection Kit from Attila Biosystems). They were processed by PCR multiplex Filmarray® RP 2.0. The characteristics and symptoms of the patients were then described. Results: 12/21 (60%) were outpatients and 8/21 (40%) were hospitalized. 57% of patients were older than 5 years, 24% under 1 year and 19% between 1 and 5 years. The most frequent symptom was fever 18/21 (86%). 90,5% (19/21) of the samples showed no detection of other pathogens. Rhino/enterovirus was detected in one sample and NL63 in another Coronavirus; both belonged to two patients with underlying diseases. Conclusion: The rate of co-infections was 9,5%. This number could be dueto the low circulation of respiratory pathogens in a context with measures to prevent contagion. In the current state of increased circulation of endemic respiratory viruses, the search for co-infections with COVID-19 is of interest


Assuntos
Coinfecção , SARS-CoV-2 , Pediatria
8.
Diabetes Care ; 44(5): 1219-1227, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33722880

RESUMO

OBJECTIVE: In observational data, lower levels of lipoprotein(a) have been associated with greater prevalence of type 2 diabetes. Whether pharmacologic lowering of lipoprotein(a) influences incident type 2 diabetes is unknown. We determined the relationship of lipoprotein(a) concentration with incident type 2 diabetes and effects of treatment with alirocumab, a PCSK9 inhibitor. RESEARCH DESIGN AND METHODS: In the ODYSSEY OUTCOMES trial alirocumab was compared with placebo in patients with acute coronary syndrome. Incident diabetes was determined from laboratory, medication, and adverse event data. RESULTS: Among 13,480 patients without diabetes at baseline, 1,324 developed type 2 diabetes over a median 2.7 years. Median baseline lipoprotein(a) was 21.9 mg/dL. With placebo, 10 mg/dL lower baseline lipoprotein(a) was associated with hazard ratio 1.04 (95% CI 1.02-1.06, P < 0.001) for incident type 2 diabetes. Alirocumab reduced lipoprotein(a) by a median 23.2% with greater absolute reductions from higher baseline levels and no overall effect on incident type 2 diabetes (hazard ratio 0.95, 95% CI 0.85-1.05). At low baseline lipoprotein(a) levels, alirocumab tended to reduce incident type 2 diabetes, while at high baseline lipoprotein(a) alirocumab tended to increase incident type 2 diabetes compared with placebo (treatment-baseline lipoprotein(a) interaction P = 0.006). In the alirocumab group, a 10 mg/dL decrease in lipoprotein(a) from baseline was associated with hazard ratio 1.07 (95% CI 1.03-1.12; P = 0.0002) for incident type 2 diabetes. CONCLUSIONS: In patients with acute coronary syndrome, baseline lipoprotein(a) concentration associated inversely with incident type 2 diabetes. Alirocumab had neutral overall effect on incident type 2 diabetes. However, treatment-related reductions in lipoprotein(a), more pronounced from high baseline levels, were associated with increased risk of incident type 2 diabetes. Whether these findings pertain to other therapies that reduce lipoprotein(a) is undetermined.


Assuntos
Anticolesterolemiantes , Diabetes Mellitus Tipo 2 , Anticorpos Monoclonais Humanizados , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Método Duplo-Cego , Humanos , Lipoproteína(a) , Pró-Proteína Convertase 9 , Resultado do Tratamento
9.
Eur J Prev Cardiol ; 28(1): 33-43, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33755145

RESUMO

AIMS: Statins are pivotal to the secondary prevention of major adverse cardiovascular events, but some patients are statin-intolerant. We examined the effects of the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor alirocumab on the risk of major adverse cardiovascular events according to the intensity of background statin treatment. METHODS AND RESULTS: The ODYSSEY OUTCOMES trial compared alirocumab with placebo in 18,924 patients with acute coronary syndrome and dyslipidaemia despite intensive or maximum-tolerated statin treatment (including no statin if intolerance was documented). The primary outcome (major adverse cardiovascular events) comprised coronary heart disease death, non-fatal myocardial infarction, ischaemic stroke, or unstable angina. Median follow-up was 2.8 years. Baseline statin treatment was high-intensity (88.8%), low/moderate-intensity (8.7%) or none (2.4%). Median baseline low-density lipoprotein cholesterol was 86, 89 and 139 mg/dL (P < 0.001) in these statin treatment categories, respectively. Alirocumab produced similar relative reductions in low-density lipoprotein cholesterol from baseline across statin treatment subgroups, but the mean absolute reductions differed (52.9, 56.7 and 86.1 mg/dL, respectively; P < 0.001). With placebo, the incidence of major adverse cardiovascular events was highest in the no statin subgroup (10.8%, 10.7% and 26.0% respectively). Alirocumab reduced major adverse cardiovascular events in each statin subgroup (hazard ratio 0.88, 95% confidence interval (CI) 0.80-0.96; 0.68, 0.49-0.94; and 0.65, 0.44-0.97, respectively; Pinteraction = 0.14) with a gradient of absolute risk reduction: 1.25%, 95% CI 0.34-2.16; 3.16%, 0.38-5.94; 7.97%, 0.42-15.51; Pinteraction = 0.106). CONCLUSIONS: PCSK9 inhibition with alirocumab reduces the relative risk of major adverse cardiovascular events after acute coronary syndrome irrespective of background statin treatment. However, patients on no statin are at high absolute risk for recurrent major adverse cardiovascular events; alirocumab substantially reduces that risk. PCSK9 inhibition may be an important therapeutic strategy for statin-intolerant patients with acute coronary syndrome.


Assuntos
Síndrome Coronariana Aguda , Anticolesterolemiantes , Isquemia Encefálica , Inibidores de Hidroximetilglutaril-CoA Redutases , Acidente Vascular Cerebral , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/tratamento farmacológico , Anticorpos Monoclonais Humanizados , Anticolesterolemiantes/efeitos adversos , Humanos , Pró-Proteína Convertase 9 , Resultado do Tratamento
10.
Fink, Thais T.; Marques, Heloisa H.S.; Gualano, Bruno; Lindoso, Livia; Bain, Vera; Astley, Camilla; Martins, Fernanda; Matheus, Denise; Matsuo, Olivia M.; Suguita, Priscila; Trindade, Vitor; Paula, Camila S.Y.; Farhat, Sylvia C.L.; Palmeira, Patricia; Leal, Gabriela N.; Suzuki, Lisa; Odone Filho, Vicente; Carneiro-Sampaio, Magda; Duarte, Alberto José S.; Antonangelo, Leila; Batisttella, Linamara R.; Polanczyk, Guilherme V.; Pereira, Rosa Maria R.; Carvalho, Carlos Roberto R.; Buchpiguel, Carlos A.; Xavier, Ana Claudia L.; Seelaender, Marilia; Silva, Clovis Artur; Pereira, Maria Fernanda B.; Sallum, Adriana M. E.; Brentani, Alexandra V. M.; Neto, Álvaro José S.; Ihara, Amanda; Santos, Andrea R.; Canton, Ana Pinheiro M.; Watanabe, Andreia; Santos, Angélica C. dos; Pastorino, Antonio C.; Franco, Bernadette D. G. M.; Caruzo, Bruna; Ceneviva, Carina; Martins, Carolina C. M. F.; Prado, Danilo; Abellan, Deipara M.; Benatti, Fabiana B.; Smaria, Fabiana; Gonçalves, Fernanda T.; Penteado, Fernando D.; Castro, Gabriela S. F. de; Gonçalves, Guilherme S.; Roschel, Hamilton; Disi, Ilana R.; Marques, Isabela G.; Castro, Inar A.; Buscatti, Izabel M.; Faiad, Jaline Z.; Fiamoncini, Jarlei; Rodrigues, Joaquim C.; Carneiro, Jorge D. A.; Paz, Jose A.; Ferreira, Juliana C.; Ferreira, Juliana C. O.; Silva, Katia R.; Bastos, Karina L. M.; Kozu, Katia; Cristofani, Lilian M.; Souza, Lucas V. B.; Campos, Lucia M. A.; Silva Filho, Luiz Vicente R. F.; Sapienza, Marcelo T.; Lima, Marcos S.; Garanito, Marlene P.; Santos, Márcia F. A.; Dorna, Mayra B.; Aikawa, Nadia E.; Litvinov, Nadia; Sakita, Neusa K.; Gaiolla, Paula V. V.; Pasqualucci, Paula; Toma, Ricardo K.; Correa-Silva, Simone; Sieczkowska, Sofia M.; Imamura, Marta; Forsait, Silvana; Santos, Vera A.; Zheng, Yingying; HC-FMUSP Pediatric Post-COVID-19 Study Group.
Clinics ; Clinics;76: e3511, 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1350613

RESUMO

OBJECTIVES: To prospectively evaluate demographic, anthropometric and health-related quality of life (HRQoL) in pediatric patients with laboratory-confirmed coronavirus disease 2019 (COVID-19) METHODS: This was a longitudinal observational study of surviving pediatric post-COVID-19 patients (n=53) and pediatric subjects without laboratory-confirmed COVID-19 included as controls (n=52) was performed. RESULTS: The median duration between COVID-19 diagnosis (n=53) and follow-up was 4.4 months (0.8-10.7). Twenty-three of 53 (43%) patients reported at least one persistent symptom at the longitudinal follow-up visit and 12/53 (23%) had long COVID-19, with at least one symptom lasting for >12 weeks. The most frequently reported symptoms at the longitudinal follow-up visit were headache (19%), severe recurrent headache (9%), tiredness (9%), dyspnea (8%), and concentration difficulty (4%). At the longitudinal follow-up visit, the frequencies of anemia (11% versus 0%, p=0.030), lymphopenia (42% versus 18%, p=0.020), C-reactive protein level of >30 mg/L (35% versus 0%, p=0.0001), and D-dimer level of >1000 ng/mL (43% versus 6%, p=0.0004) significantly reduced compared with baseline values. Chest X-ray abnormalities (11% versus 2%, p=0.178) and cardiac alterations on echocardiogram (33% versus 22%, p=0.462) were similar at both visits. Comparison of characteristic data between patients with COVID-19 at the longitudinal follow-up visit and controls showed similar age (p=0.962), proportion of male sex (p=0.907), ethnicity (p=0.566), family minimum monthly wage (p=0.664), body mass index (p=0.601), and pediatric pre-existing chronic conditions (p=1.000). The Pediatric Quality of Live Inventory 4.0 scores, median physical score (69 [0-100] versus 81 [34-100], p=0.012), and school score (60 [15-100] versus 70 [15-95], p=0.028) were significantly lower in pediatric patients with COVID-19 at the longitudinal follow-up visit than in controls. CONCLUSIONS: Pediatric patients with COVID-19 showed a longitudinal impact on HRQoL parameters, particularly in physical/school domains, reinforcing the need for a prospective multidisciplinary approach for these patients. These data highlight the importance of closer monitoring of children and adolescents by the clinical team after COVID-19.


Assuntos
Humanos , Masculino , Criança , Adolescente , COVID-19/complicações , Qualidade de Vida , Estudos Prospectivos , Centros de Atenção Terciária , Teste para COVID-19 , SARS-CoV-2 , América Latina
11.
An Acad Bras Cienc ; 92(4): e20200435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33295580

RESUMO

Osteoporosis is a metabolic disorder characterized by a loss of bone mass and structure and increasing the risk of fragility fractures, mostly among postmenopausal women. Sheep is a recognized large animal model for osteoporosis research. An experimental group of ewes (3-4 years old) was subjected to ovariectomy (OVX) and weekly glucocorticoid (GC) application for 24 weeks and compared with a sham control group. Blood and bone marrow parameters were analyzed before and 24 weeks after OVX and GC administration. Osteopenia was confirmed through micro-computed tomography and histomorphometric analysis of L4 vertebra in the study end. A statistically significant increase was observed in mean corpuscular volume, mean cell hemoglobin and monocytes and a decrease in red blood count and eosinophils (p<0.05). Alkaline phosphatase (ALP), gamma-glutamyl transpeptidase, magnesium and α1-globulin increased, and creatinine, albumin, sodium and estradiol decreased (p<0.05). A slight decrease of bone formation markers (bone ALP and osteocalcin) and an increase of bone resorption markers (C-terminal telopeptides of collagen type 1 and tartrate-resistant acid phosphatase) were observed, but without statistical significance. This study aims to contribute to better knowledge of sheep as a model for osteoporosis research and the consequences that a performed induction protocol may impose on organic metabolism.


Assuntos
Hematologia , Osteoporose , Animais , Medula Óssea , Remodelação Óssea , Pré-Escolar , Feminino , Glucocorticoides , Humanos , Ovariectomia , Pesquisa , Ovinos , Microtomografia por Raio-X
12.
Molecules ; 25(19)2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32992439

RESUMO

Magnetic nanoparticles such as cobalt ferrite are investigated under clinical hyperthermia conditions for the treatment of cancer. Cobalt ferrite nanoparticles (CFNPs) synthesized by the thermal decomposition method, using nonionic surfactant Triton-X100, possess hydrophilic polyethylene oxide chains acting as reducing agents for the cobalt and iron precursors. The monodispersed nanoparticles were of 10 nm size, as confirmed by high-resolution transmission electron microscopy (HR-TEM). The X-ray diffraction patterns of CFNPs prove the existence of cubic spinel cobalt ferrites. Cs-corrected scanning transmission electron microscopy-high-angle annular dark-field imaging (STEM-HAADF) of CFNPs confirmed their multi-twinned crystallinity due to the presence of atomic columns and defects in the nanostructure. Magnetic measurements proved that the CFNPs possess reduced remnant magnetization (MR/MS) (0.86), which justifies cubic anisotropy in the system. Microwave-based hyperthermia studies performed at 2.45 GHz under clinical conditions in physiological saline increased the temperature of the CFNP samples due to the transformation of radiation energy to heat. The specific absorption rate of CFNPs in physiological saline was 68.28 W/g. Furthermore, when triple-negative breast cancer cells (TNBC) in the presence of increasing CFNP concentration (5 mg/mL to 40 mg/mL) were exposed to microwaves, the cell cytotoxicity was enhanced compared to CFNPs alone.


Assuntos
Antineoplásicos , Cobalto , Compostos Férricos , Hipertermia Induzida , Campos Magnéticos , Nanopartículas , Neoplasias de Mama Triplo Negativas/terapia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cobalto/química , Cobalto/farmacologia , Feminino , Compostos Férricos/síntese química , Compostos Férricos/química , Compostos Férricos/farmacologia , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico
13.
J Healthc Eng ; 2020: 5950218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802299

RESUMO

Gel-based electrodes are employed to record sEMG signals for prolonged periods. These signals are used for the control of myoelectric prostheses, clinical analysis, or sports medicine. However, when the gel dries, the electrode-skin impedance increases considerably. Using dry active electrodes (AEs) to compensate variations of impedance is an alternative for long-term recording. This work describes the optimization of the electronic design of a conventional AE by removing the impedance coupling stage and two filters. The proposed work consisted of 5 stages: electrodes, amplification (X250), 2.2 Vdc offset, low-pass filter, and ADC with USART communication. The device did not need the use of electrolytic gel. The measurements of CMRR (96 dB), amplitude of the output sEMG signal (∼1.6 Vp-p), and system bandwidth (15-450 Hz) were performed in order to confirm the reliability of the device as an sEMG signal acquisition system. The SNR values from seven movements performed by eleven volunteers were compared in order to measure the repeatability of the measurements (average 30.32 dB for a wrist flexion). The SNR for wrist flexion measured with the proposed and the commercial system was compared; the values were 49 dB and 60 dB, respectively.


Assuntos
Cobre , Eletrodos , Eletroencefalografia/métodos , Eletromiografia/métodos , Dispositivos Eletrônicos Vestíveis , Articulação do Punho/fisiologia , Zinco , Adulto , Comunicação , Impedância Elétrica , Eletrônica , Feminino , Géis , Humanos , Masculino , Movimento , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Punho
14.
AIDS Behav ; 24(3): 839-846, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30945030

RESUMO

To assess the potential for decreased condom use as pre-exposure prophylaxis (PrEP) is scaled-up in Latin America, we examined HIV prevention method preferences (neither PrEP nor condoms, condoms only, PrEP only, or PrEP with condoms) within 1302 sexual partnerships reported by 397 HIV-negative men who have sex with men (MSM) and transgender women (TW) in Tijuana, Mexico. Using PrEP with condoms (56%) was preferred to using condoms only (24%), using PrEP only (17%), and using neither PrEP nor condoms (3%). Compared to using condoms only, using PrEP only was preferred within primary (adjusted odds ratio [AOR] = 4.13, 95% confidence interval [CI] 1.92, 8.90) and condomless sex practicing (AOR = 6.97, 95% CI 3.92, 12.40) partnerships, suggesting PrEP use may not displace condom use among MSM and TW in Tijuana and other similar settings.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/psicologia , Preferência do Paciente , Profilaxia Pré-Exposição/métodos , Pessoas Transgênero/psicologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Preservativos , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , México , Pessoa de Meia-Idade , Sexo Seguro , Comportamento Sexual , Parceiros Sexuais , Pessoas Transgênero/estatística & dados numéricos
15.
Int J Biol Macromol ; 147: 1136-1145, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739047

RESUMO

Biopolymeric blends based on bacterial cellulose (BC) films modified with low molecular weight chitosan (Chi) were developed for controlled release of ciprofloxacin (Cip). Biophysical studies revealed a compatible and cooperative network between BC and Chi including deep structural changes in the BC matrix shown by spectroscopic and thermal analyses (SEM, roughness analysis, FTIR, XRD, TGA, mechanical properties and water vapor transmission rate). Incorporation of chitosan to BC matrix generated a thickening scaffold with high permeability to water vapor from 0.7 to 3.2 g mm/m2 h. Cip loaded onto the BC-Chi film showed a hyperbolic release profile with a 30% decrease in antibiotic release mediated by the presence of Chi. BC-Chi blend films containing Cip tested against Pseudomonas aeruginosa and Staphylococcus aureus showed a synergic effect of chitosan on Cip antimicrobial activity. Besides, in vitro studies revealed the lack of cytotoxicity of BC-Chi-Cip films in human fibroblasts.


Assuntos
Anti-Infecciosos/química , Bandagens , Celulose/química , Quitosana/química , Ciprofloxacina/química , Fibroblastos/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Linhagem Celular , Ciprofloxacina/farmacologia , Fibroblastos/metabolismo , Temperatura Alta , Humanos , Peso Molecular , Permeabilidade , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria
16.
Rev Cardiovasc Med ; 21(4): 561-564, 2020 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-33388000

RESUMO

Social Media usage has been shown to increase in situations of natural disaster and other crises. It is crucial for the scientific community to understand how social media works in order to enhance our capabilities and make a more resilient community. Through social media communication, the scientific community can collaborate around the globe in a faster way the most important findings of a disease, with a decreased knowledge transition time to other healthcare providers (HCPs). This is greatly important to coordinate research and knowledge during a time of uncertainty and protentional fake news. During the 2020 global pandemic, social media has become an ally but also a potential threat. High volumes of information compressed into a short period can result in overwhelmed HCPs trying to discern fact from noise. A major limitation of social media currently is the ability to quickly disseminate false information which can confuse and distract. Society relies on educated scientists and physicians to be leaders in delivering fact-based information to the public. For this reason, in times of crises it is important to be leaders in the conversation of social media to guide correct and helpful information and knowledge to the masses looking for answers.


Assuntos
COVID-19/epidemiologia , Pandemias , SARS-CoV-2 , Mídias Sociais/organização & administração , Humanos
17.
Rev. MVZ Córdoba ; 24(3): 7291-7296, sep.-dic. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1115253

RESUMO

RESUMEN Objetivo. Evaluar el efecto de dosis crecientes del glucósido cianogénico Linamarina, en la reducción de metano ruminal in vitro. Materiales y Métodos. Se empleó líquido ruminal de dos ovejas fistuladas de la raza Merino Precoz, con el que se inoculó un sustrato fermentativo constituido por heno de alfalfa (Medicago sativa) y grano de avena molido (Avena sativa L.), se adicionó solución buffer y Linamarina (pureza de ≥98%) en dosis crecientes, lo que se llevó a incubación por ocho horas in vitro. El metano se midió cada hora, con un monitor de gases infrarrojo. Resultados. De acuerdo con el incremento de las dosis de Linamarina (0, 6, 13, 20 y 26 mg/L), la concentración de metano disminuyó de forma lineal (p≤0.05) en (9.7, 9.2, 18.1 y 29.4%) respectivamente. Se observó una reducción significativa de metano con la dosis más alta de Linamarina. Conclusión. La Linamarina, en su estado puro, fue eficaz en la reducción de metano durante la fermentación ruminal in vitro. Por lo tanto, este estudio constituye una base para futuros experimentos que incluyan fuentes vegetales de Linamarina y otras variables ruminales, lo que puede conducir a encontrar estrategias para reducir los gases de efecto invernadero.


ABSTRACT Objective. To assess the effect of rising doses of the cyanogenic glucoside Linamarin on the reduction of in vitro rumen methane. Materials and methods. Rumen fluid from two fistulated Merino Precoz sheep, inoculated with a fermentation substrate comprising alfalfa hay (Medicago sativa) and ground oat grain (Avena sativa L.), and added with buffer solution and Linamarin (purity ≥98%) in rising doses, was incubated for eight hours in vitro. Methane was measured each hour with an infrared gas monitor. Results. According Linamarin doses were increased (0, 6, 13, 20 and 26 mg/L), the methane concentration fell in a linear manner (p≤0.05) by (9.7, 9.2, 18.1 and 29.4%), respectively. A significant reduction of methane was seen whit the highest dose of Linamarin. Conclusions. Linamarin, in pure state, was effective to reduce methane during in vitro ruminal fermentation. Therefore, this study constitutes a basis for future experiments including vegetable sources of Linamarin as well as other rumen variables, leading to find a strategy for reducing greenhouse gases.


Assuntos
Técnicas In Vitro , Aditivos Alimentares , Glucosídeos , Metano , Fermentação
18.
Mol Genet Genomic Med ; 7(12): e997, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31574590

RESUMO

BACKGROUND: Malan syndrome is a recently introduced overgrowth disorder described in a limited number of individuals. Haploinsufficiency and also point mutations of NFIX gene have been proposed as its leading causative mechanism, however, due to the limited number of cases and different deletion sizes, genotype/phenotype correlations are still limited. METHODS: Here, we report the first Brazilian case of Malan syndrome caused by a 990 kb deletion in 19p13.2p13.12, focusing on clinical and behavioral aspects of the syndrome. RESULTS: The patient presented with macrocephaly, facial dysmorphisms, hypotonia, developmental delay, moderate thoracolumbar scoliosis, and seizures. The intellectual and behavioral assessments showed severe cognitive, language, and adaptive functions impairments. The 19p deleted region of our patient encompasses NFIX, CACNA1A, which seems to be related to a higher frequency of seizures among individuals with microdeletions in 19p13.2, and 15 other coding genes, including CC2D1A and NACC1, both known to be involved in neurobiological process and pathways. CONCLUSION: Deletions involving NFIX gene should be considered in patients with overgrowth during childhood, macrocephaly, developmental delay, and seizures, as well as severe intellectual disability.


Assuntos
Canais de Cálcio/genética , Deleção Cromossômica , Fatores de Transcrição NFI/genética , Transtornos do Neurodesenvolvimento/genética , Brasil , Cromossomos Humanos Par 19/genética , Estudos de Associação Genética , Humanos , Deficiência Intelectual/genética , Masculino , Megalencefalia/genética , Convulsões/genética , Adulto Jovem
19.
Bioengineering (Basel) ; 6(3)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466238

RESUMO

The study of the noble metal magnetic hybrid nanoparticles is a really promising topic from both the scientific and the technological points of views, with applications in several fields. Iron oxide materials which are hybridized with noble metal nanoparticles (NPs) have attracted increasing interest among researchers because of their cooperative effects on combined magnetic, electronic, photonic, and catalytic activities. This review article contains a summary of magnetic noble metal/iron oxide nanoparticle systems potentially useful in practical biomedical applications. Among the applications, engineered devices for both medical diagnosis and treatments were considered. The preparation to produce different structures, as blends or core-shell structures, of several nanometric systems was also considered. Several characterization techniques available to describe the structure, morphology and different kinds of properties of hybrid nanoparticles are also included in this review.

20.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);95(3): 298-305, May-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1012614

RESUMO

Abstract Objective: To describe and analyze indicators of feeding practices related to breastfeeding and factors associated with exclusive breastfeeding (EBF) in a subnormal urban cluster (slums) in Pernambuco, Brazil. Methods: Four breastfeeding indicators were used to interview mothers of children under 3 years of age. An inventory of the families' socioeconomic and environmental factors, maternal obstetric history, and basic health care access was undertaken. The sample consisted of all 310 children under the age of 3 years from Coelhos, PE, Brazil. Spearman's correlation was carried out, as well as crude and adjusted prevalence ratios for a final statistical model that showed associated factors with the main outcome at a level of 0.05. Results: The prevalence of breastfeeding in the first hour of life, exclusive breastfeeding up to 6 months, continued breastfeeding at 1 year, and continued breastfeeding at 2 years were 60.2%, 32.9%, 45.9, and 35.9%, respectively. A correlation was observed between start of pacifier use and duration of either exclusive (r s = 0.358 [p < 0.001]) or non‐exclusive breastfeeding (r s = 0.248 [p = 0.006]). Maternal age over 35 years (p < 0.001), home visit in the first week after birth (p = 0.003), having had a male baby (p = 0.029), and not using a pacifier (p < 0.001) remained protective factors in the final model. Conclusion: The prevalence rates of exclusive breastfeeding at 6 months were well above the results obtained by other Brazilian authors. Home visit and maternal age prevailed as protective factors, while pacifier use was shown to be a discouraging practice.


Resumo Objetivo: Descrever e analisar indicadores das práticas relacionadas ao aleitamento materno e fatores associados ao aleitamento materno exclusivo em um aglomerado urbano subnormal (favela) em Pernambuco. Métodos: Foram usados quatro indicadores do aleitamento materno mediante entrevista com as mães de menores de três anos. Fez-se um inventário de fatores socioambientais das famílias, antecedentes obstétricos e acesso às ações básicas de saúde. A amostra inclui todas as 310 crianças da Comunidade de Coelhos, PE, Brasil. Feitas correlação de Spearman e razões de prevalências brutas e ajustadas que compuseram um modelo estatístico final que evidenciou os fatores associados ao principal desfecho ao nível de 0,05. Resultados: A prevalência do aleitamento materno na primeira hora de vida, aleitamento materno exclusivo aos 6 meses, amamentação continuada até um ano e dois anos foram, respectivamente, 60,2%, 32,9%, 45,9% e 35,9%. Na correlação entre o início do uso de chupeta e a duração do aleitamento, exclusivo ou não, obtiveram-se respectivamente os coeficientes rs = 0,358 (p < 0,001) e rs = 0,248 (p = 0,006). No modelo final permaneceram como fatores de proteção: a idade materna acima de 35 anos (p < 0,001), a visita domiciliar na primeira semana de vida (p = 0,003), o sexo masculino (p = 0,029) e o não uso da chupeta (p < 0,001). Conclusão: Os índices de prevalência do aleitamento materno exclusivo aos 6 meses foram bem superiores aos resultados obtidos por outras pesquisas nacionais. A visita domiciliar e a idade materna prevaleceram como fatores de proteção e o uso de chupeta como uma prática desestimulante.


Assuntos
Humanos , Feminino , Recém-Nascido , Lactente , Aleitamento Materno/estatística & dados numéricos , Saúde da Família , Programas Nacionais de Saúde , Fatores Socioeconômicos , População Urbana , Brasil/epidemiologia , Análise por Conglomerados , Prevalência , Estudos Transversais , Chupetas
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