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1.
J Transl Med ; 22(1): 14, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172991

RESUMEN

BACKGROUND: Neoantigens are patient- and tumor-specific peptides that arise from somatic mutations. They stand as promising targets for personalized therapeutic cancer vaccines. The identification process for neoantigens has evolved with the use of next-generation sequencing technologies and bioinformatic tools in tumor genomics. However, in-silico strategies for selecting immunogenic neoantigens still have very low accuracy rates, since they mainly focus on predicting peptide binding to Major Histocompatibility Complex (MHC) molecules, which is key but not the sole determinant for immunogenicity. Moreover, the therapeutic potential of neoantigen-based vaccines may be enhanced using an optimal delivery platform that elicits robust de novo immune responses. METHODS: We developed a novel neoantigen selection pipeline based on existing software combined with a novel prediction method, the Neoantigen Optimization Algorithm (NOAH), which takes into account structural features of the peptide/MHC-I interaction, as well as the interaction between the peptide/MHC-I complex and the TCR, in its prediction strategy. Moreover, to maximize neoantigens' therapeutic potential, neoantigen-based vaccines should be manufactured in an optimal delivery platform that elicits robust de novo immune responses and bypasses central and peripheral tolerance. RESULTS: We generated a highly immunogenic vaccine platform based on engineered HIV-1 Gag-based Virus-Like Particles (VLPs) expressing a high copy number of each in silico selected neoantigen. We tested different neoantigen-loaded VLPs (neoVLPs) in a B16-F10 melanoma mouse model to evaluate their capability to generate new immunogenic specificities. NeoVLPs were used in in vivo immunogenicity and tumor challenge experiments. CONCLUSIONS: Our results indicate the relevance of incorporating other immunogenic determinants beyond the binding of neoantigens to MHC-I. Thus, neoVLPs loaded with neoantigens enhancing the interaction with the TCR can promote the generation of de novo antitumor-specific immune responses, resulting in a delay in tumor growth. Vaccination with the neoVLP platform is a robust alternative to current therapeutic vaccine approaches and a promising candidate for future personalized immunotherapy.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Vacunas , Humanos , Animales , Ratones , Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Péptidos , Receptores de Antígenos de Linfocitos T/metabolismo , Inmunoterapia/métodos
2.
Trop Anim Health Prod ; 56(2): 53, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38261014

RESUMEN

The study aimed to evaluate the inclusion effects of Stryphnodendron rotundifolium (barbatimão) extracts in substitution of the lasalocid sodium on the ingestive behaviour, intake, ruminal parameters, and digestibility of feedlot lambs. Twenty-four pantaneiro lambs were used, with an average age of 150 ± 4.59 days and an initial body weight of 21.2 ± 3.63 kg. The lambs were distributed in three treatments in an experimental design with randomized blocks. The treatments correspond to the additive supplements: LAS (0.019 g of lasalocid sodium/lamb/d); DGB (1.50 g of barbatimão dried ground bark/lamb/d); DHE (0.30 g of barbatimão dry hydroalcoholic extract/lamb/d). The DHE increased 59.74 min in the time spent for ingestion per day, resulting in an efficiency reduction of dry matter (DM) ingestion (127 g of DM/h of feed). There was a reduction of 1.8 mg/dL in the ammoniacal nitrogen concentration with extract supplementation compared to LAS. The DGB reduced total volatile fatty acids by 48.9% compared to the control treatment. The inclusion of barbatimão extracts (DGB and DHE) reduced 12.05% of ruminal butyrate content. The supplementation of barbatimão extracts replacing lasalocid sodium in the diet of feedlot lambs did not affect intake and caused small changes on ingestive behaviour.


Asunto(s)
Fabaceae , Lasalocido , Ovinos , Animales , Corteza de la Planta , Oveja Doméstica , Extractos Vegetales/farmacología , Sodio
3.
Exp Cell Res ; 417(1): 113207, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35580698

RESUMEN

Melanoma spheroid-loaded 3D skin models allow for the study of crucial tumor characteristics and factors at a superior level because the neoplastic cells are integrated into essential human skin components, permitting tumor-skin model communication. Herein, we designed a melanoma-containing artificial dermis by inserting multicellular tumor spheroids from the metastatic phase of WM 1617 melanoma cells into an artificial dermis. We cultured multicellular melanoma spheroids by hanging drop method (250 cells per drop) with a size of 420 µm in diameter after incubation for 14 days. These spheroids were integrated into the dermal equivalents that had been previously preparedwith a type-I collagen matrix and healthy fibroblasts. The melanoma spheroid cells invaded and proliferated in the artificial dermis. Spheroids treated with a 1.0 µmol/L aluminum chloride phthalocyanine nanoemulsion in the absence of light showed high cell viability. In contrast, under irradiation with visible red light (660 nm) at 25 J/cm2, melanoma cells were killed and the healthy tissue was preserved, indicating that photodynamic therapy is effective in such a model. Therefore, the 3D skin melanoma model has potential to promote research in full-thickness skin model targeting optimized preclinical assays.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Dermis , Humanos , Esferoides Celulares , Melanoma Cutáneo Maligno
4.
Trop Anim Health Prod ; 54(5): 335, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36197512

RESUMEN

This research was carried out to evaluate the effect of replacing dietary soybean meal with peanut meal, on intake and digestibility, microbial protein synthesis, and nitrogen balance in lactating cows. Twelve crossbred Holstein × Gyr cows at 84 days in milk (DIM) were distributed in a triple 4 × 4 Latin square. The treatments consisted of increasing peanut meal levels (0, 330, 670, and 1000 g/kg dry matter basis) in replacement of soybean meal in the diet. Replacing soybean meal with peanut meal had no effect on the intake and digestibility of dry matter and nutrients. Nitrogen balance and percentage of retained were similar among treatments. Microbial nitrogen synthesis and microbial protein synthesis efficiency were similar among treatments. Thus, in regions where its cost is lower, peanut meal can totally replace soybean meal in dairy cow diets without affecting nitrogen balance and microbial protein synthesis.


Asunto(s)
Glycine max , Lactancia , Alimentación Animal/análisis , Animales , Arachis , Bovinos , Dieta/veterinaria , Digestión , Femenino , Leche/química , Nitrógeno/metabolismo , Rumen/metabolismo , Glycine max/metabolismo , Zea mays/metabolismo
5.
Trop Anim Health Prod ; 54(1): 80, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35080682

RESUMEN

The objective of this study was to evaluate the effects of replacing soybean meal with peanut meal on milk production, chemical and fatty acid composition, nutritional quality indicators of the lipid fraction, and the economic viability of the diets. Twelve crossbred cows in the initial lactation third, with a bodyweight of 545 ± 37 kg and average milk production of 28 kg/day of milk were distributed in a 4 × 4, triple Latin square design. The treatments consisted of diets with substitution levels of soybean meal for peanut meal (0; 330; 670; and 1000 g/kg in DM). The peanut meal inclusion to replace soybean meal in the diets provided a decreasing linear effect for the protein (P = 0.02) and casein (P = 0.01) concentration in milk. Milk production, total solids concentration, feed efficiency, fatty acid composition, and nutritional quality indicators of the milk lipid fraction were not influenced by the substitution levels. The diet cost per kg DM decreased due to the peanut meal inclusion as a protein source. The partial or total substitution of soybean meal for peanut meal in the feedlot cows diet reduces the cost of feed, without affecting milk production and total solids yield.


Asunto(s)
Glycine max , Lactancia , Alimentación Animal/análisis , Animales , Arachis , Bovinos , Dieta/veterinaria , Femenino , Leche , Rumen
6.
Genetica ; 148(3-4): 183-193, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32770285

RESUMEN

The Monteiro is a feral pig found in the Brazilian Pantanal ecosystem. The goal of this research is to generate data and knolewdge related to animal populations wich can be used for management and development of an in vitro conservation program for animal resourses at Pantanal ecosystem. The present study evaluated animals sampled from 10 distinct locations within the region, using 19 microsatellite markers (N = 189) and the control region of mitochondrial DNA (mtDNA) (N = 392). Low genetic differences were found between populations with the microsatellite data. The FST range was between 0.009 and 0.063 (p-value < 0.05). The Mantel test corroborated with previous results, as low correlations between genetic and geographic distances were observed (r2 = 0.2309, p = 0.06). Bayesian analysis for genetic structure identification placed the Monteiro pigs into three main clusters (MOB, Pop 1 and all others Pantanal populations). Most of the Monteiro pigs share a single European haplotype as seen by mtDNA analyses. This haplotype is not exclusive, as it is shared with other swine populations (commercial and other locally adapted breeds). Monteiro populations from different geographic locations within Pantanal are not isolated and can be considered as a large unique population. Since animals roam freely to seek food and water, or even due to seasonal flooding of their habitat, the Monteiro populations presented absence of major genetic structure and evidence of high gene flow. These results can be used to create a management plan and in situ and ex situ conservation program for conservation and use of the Monteiro breed in the Pantanal ecosystem.


Asunto(s)
Animales Salvajes/genética , Polimorfismo Genético , Porcinos/genética , Humedales , Distribución Animal , Animales , Animales Salvajes/fisiología , Brasil , ADN Mitocondrial/genética , Haplotipos , Repeticiones de Microsatélite , Filogeografía , Porcinos/fisiología
7.
Photochem Photobiol Sci ; 19(1): 40-48, 2020 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-31776533

RESUMEN

Although the dichlorofluorescein (DCF) assay is widely used to detect the production of UVA-induced ROS, the photostability and phototoxicity of the probe after UVA irradiation remains controversial and the experimental conditions often vary across studies, making it difficult to compare results from different studies. This study aimed to evaluate the suitability of the DCF assay for detection of UVA-induced ROS in human cells after UVA irradiation. Human primary fibroblasts (HPF) and HaCaT cells were loaded with 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) (2, 10, and 50 µM) for 10 and 30 min, before and after exposure to UVA radiation (5-50 J cm-2). Fluorescence was recorded immediately or 30 min after irradiation using three different techniques: microplate reading, flow cytometry, and confocal scanning microscopy. Cell viability was assessed by flow cytometry before and after UVA exposure. A UVA-dose-dependent increase in ROS was observed at 5-50 µM DCFDA, and the magnitude of the fluorescent signal was affected by RPMI medium, as well as DCFDA loading concentration and incubation period. However, higher concentrations of DCFDA compromised the viability of both HaCaT and HPF cells after UVA irradiation. The most sensitive and reliable combination for the ROS assay was pre-incubation with 10 µM DCFDA for 30 min in PBS. Reading the fluorescence 30 min after UVA irradiation diminished the emission signal, as did the DCFDA post-incubation. In conclusion, this single-point DCF assay allowed reproducible and sensitive UVA-induced ROS detection in HaCaT and HPF cells without compromising the cell viability or morphology.


Asunto(s)
Fibroblastos/efectos de la radiación , Fluoresceínas/farmacología , Queratinocitos/efectos de la radiación , Estrés Oxidativo/efectos de la radiación , Rayos Ultravioleta , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Fluoresceínas/química , Humanos , Procesos Fotoquímicos/efectos de la radiación , Relación Estructura-Actividad
8.
Reprod Domest Anim ; 55(2): 154-161, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31804747

RESUMEN

In contributing to the conservation of wild rodents, the aim of this study was to evaluate the use of distinct cryoprotectants, separately or in combination, for solid surface vitrification (SSV) of red-rumped agouti ovarian tissue. Ovarian cortex from nine females was recovered and fragmented. Fresh fragments (control) were used to analyse the pre-antral follicle (PF) morphology using a histologic procedure, viability using the Trypan blue test, cell proliferation by counting the argyrophilic nucleolar organizing regions (Ag-NORs technique) and DNA integrity using the TUNEL assay. The remaining fragments were vitrified using SSV method with 3 M or 6 M ethylene glycol (EG) or dimethyl sulfoxide (DMSO), or in combination (3 M EG/3 M DMSO), and further evaluated as reported for the fresh samples. All cryoprotectants were effective at preserving PFs morphology compared to the control group (80.7 ± 5.21%), except 6 M EG and 3 M DMSO that provoked a significant (p < .05) decrease on the values of morphologically normal primary (60.0 ± 19.0%) and primordial (44 ± 4.5%) follicles, respectively. Regarding viability, all cryoprotectants provided values similar to that verified for the control group (79.0%), but a significant decrease (p < .05) was observed with EG/DMSO combination (59%). Using Ag-NORs technique, the highest (p < .05) cell proliferative capacity was detected when using EG at each tested concentration. The TUNEL proved the preservation of DNA integrity regardless of the cryoprotectant. In summary, we suggest the use of 3 M EG for the solid surface vitrification of red-rumped agouti ovarian tissue.


Asunto(s)
Criopreservación/veterinaria , Crioprotectores , Dasyproctidae , Ovario , Animales , Supervivencia Celular , Criopreservación/métodos , Daño del ADN , Dimetilsulfóxido , Glicol de Etileno , Femenino , Folículo Ovárico
9.
Microb Pathog ; 130: 71-80, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30844473

RESUMEN

Mandacaru (Cereus jamacaru DC.), is a cactaceous symbol of caatinga vegetation at Brazilian Northeast region, however, there are no much studies about biochemical properties of this species. Here, the pioneering study brings very relevant data to highlight the importance of research with endemic plants of the caatinga. Afterward, the presence of enzymes such as peroxidase, protease, chitinase, ß-1,3-glucanase, and serine (trypsin) and cysteine (papain) protease inhibitors were evaluated. The peroxidase activity was higher in roots than other tissues. The ß-1,3-glucanase and proteolytic activity were prominent in stem and roots. The chitinase activity and protease inhibitor for both classes analyzed were detected in the stem and fruit peel. Antifungal activity against Colletotrichum gloeosporioides showed the root extract has a promising inhibitory activity on this economical important phytopathogenic fungus. After the contact of the hyphae with root extract increase in membrane permeability, based on Propidium Iodide (PI) uptake, and production of reactive oxygen species (ROS) were detected, compared to negative control. In addition, Scanning Electron Microscopy (SEM) analysis showed morphological damage on hyphae structure indicating that the treatment debilitates either cell membrane or cell wall leading to the cell death C. gloeosporioides.


Asunto(s)
Antifúngicos/farmacología , Cactaceae/química , Membrana Celular/efectos de los fármacos , Membrana Celular/patología , Colletotrichum/crecimiento & desarrollo , Proteínas de Plantas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Antifúngicos/aislamiento & purificación , Cactaceae/enzimología , Colletotrichum/efectos de los fármacos , Colletotrichum/enzimología , Colletotrichum/ultraestructura , Enzimas/análisis , Frutas/química , Frutas/enzimología , Hifa/ultraestructura , Viabilidad Microbiana/efectos de los fármacos , Microscopía Electrónica de Rastreo , Permeabilidad/efectos de los fármacos , Proteínas de Plantas/aislamiento & purificación , Raíces de Plantas/química , Raíces de Plantas/enzimología , Tallos de la Planta/química , Tallos de la Planta/enzimología
10.
Cryobiology ; 91: 53-60, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31678072

RESUMEN

The objective was to evaluate different permeating cryoprotectants to vitrify testicular tissue biopsies from adult collared peccaries. Five pairs of testicles were dissected into fragments (9 mm³) that were allocated to non-vitrified (control) and vitrified groups using a solid-surface method following exposure to different cryoprotectants (3.0 M dimethyl sulfoxide (DMSO), 3.0 M ethylene glycol (EG) or 1.5 M DMSO + 1.5 M EG). After warming, samples were evaluated for histomorphology, ultrastructure, viability, and proliferative capacity potential. The appropriate conservation of the ultrastructural organization of the seminiferous tubule in terms of lumen presence and cell junctions was only observed at the use of DMSO/EG combination. Regardless of the cryoprotectant, the vitrification effectively preserved cell nuclear visualization and condensation similarly as observed at the non-vitrified group. Moreover, DMSO/EG combination provided a better preservation of basal membranes of seminiferous tubules than DMSO (P < 0.05). The occurrence of cell swelling was more evident in the use of DMSO than EG (P < 0.05), but both isolate cryoprotectants were similar to the DMSO/EG combination. Only the DMSO/EG combination maintained the proliferative capacity potential for spermatogonia (3.69 NORs/cell) and Sertoli cell (3.19 NORs/cell) similar to controls (3.46 and 3.31 NORS/cell, respectively). Moreover, ~40% cell viability was found after vitrification independent of cryoprotectant. In conclusion, DMSO/EG in combination is better than DMSO or EG alone for SSV of testicular tissue biopsies from adult collared peccaries.


Asunto(s)
Criopreservación/veterinaria , Crioprotectores/farmacología , Dimetilsulfóxido/farmacología , Glicol de Etileno/farmacología , Testículo/citología , Animales , Artiodáctilos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Criopreservación/métodos , Crioprotectores/química , Femenino , Masculino , Vitrificación
11.
Am J Ind Med ; 62(11): 996-1006, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31471924

RESUMEN

BACKGROUND: To investigate the relationship between precarious working conditions and the health of bus drivers and conductors. METHODS: Data were gathered by means of a survey and interviews conducted in 2012 with 1607 employees of the public transport system of the metropolitan region of Belo Horizonte, Brazil. Nine proxy variables were used to create a precariousness score, ranging from 0 to 9, on a comparative scale: score 0 "less precarious" and 9 "more precarious." Negative self-evaluations of health, medical diagnoses of depression and sleep disorders, common mental disorders, musculoskeletal pain and medical leave were assessed. Poisson regression was used to assess associations between precariousness and health adjusted for age, sex, education, vibration, and noise. RESULTS: The sample was composed of 853 drivers and 754 conductors. Most were men (87%), with age below 40 years (67.4%) and medium educational level (64.5%). The maximum precariousness score observed was 7. Most individuals were in the groups of scores 3 (26.7%) and 4 (26.1%). The prevalences of the health situations were: common mental disorders, 26.3%; medical diagnosis of depression, 9.7%; medical diagnosis of sleep disorder, 14.6%; musculoskeletal pain, 43.0%; medical leave (absenteeism), 34.8%; and negative self-evaluation of health, 20.2%. The prevalences of health conditions, with the exception of negative self-evaluations of health, were significantly higher among workers with higher levels of precarious working conditions. CONCLUSIONS: Worse health, particularly common mental disorders, was associated with self-assessed work precariousness.


Asunto(s)
Trastornos Mentales/epidemiología , Vehículos a Motor , Enfermedades Profesionales/epidemiología , Salud Laboral , Absentismo , Adolescente , Adulto , Brasil/epidemiología , Autoevaluación Diagnóstica , Femenino , Encuestas Epidemiológicas , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Dolor Musculoesquelético/epidemiología , Distribución de Poisson , Prevalencia , Factores de Riesgo , Trastornos del Sueño-Vigilia/epidemiología , Transportes , Adulto Joven
12.
Mol Ecol ; 27(1): 54-65, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29134719

RESUMEN

Population structure of many marine organisms is spatially patchy and varies within and between years, a phenomenon defined as chaotic genetic patchiness. This results from the combination of planktonic larval dispersal and environmental stochasticity. Additionally, in species with bi-partite life, postsettlement selection can magnify these genetic differences. The high fecundity (up to 500,000 eggs annually) and protracted larval duration (12-24 months) and dispersal of the southern rock lobster, Jasus edwardsii, make it a good test species for chaotic genetic patchiness and selection during early benthic life. Here, we used double digest restriction site-associated DNA sequencing (ddRADseq) to investigate chaotic genetic patchiness and postsettlement selection in this species. We assessed differences in genetic structure and diversity of recently settled pueruli across four settlement years and between two sites in southeast Australia separated by approximately 1,000 km. Postsettlement selection was investigated by identifying loci under putative positive selection between recently settled pueruli and postpueruli and quantifying differences in the magnitude and strength of the selection at each year and site. Genetic differences within and among sites through time in neutral SNP markers indicated chaotic genetic patchiness. Recently settled puerulus at the southernmost site exhibited lower genetic diversity during years of low puerulus catches, further supporting this hypothesis. Finally, analyses of outlier SNPs detected fluctuations in the magnitude and strength of the markers putatively under positive selection over space and time. One locus under putative positive selection was consistent at both locations during the same years, suggesting the existence of weak postsettlement selection.


Asunto(s)
Variación Genética , Genética de Población , Palinuridae/genética , Animales , Australia , Geografía , Heterocigoto , Polimorfismo de Nucleótido Simple/genética , Selección Genética , Análisis de Secuencia de ADN , Tasmania , Factores de Tiempo
13.
Cytokine ; 106: 35-39, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29549721

RESUMEN

This study detected and compared the levels of IFN-γ, TNF-α, TGF-ß and nitric oxide (NO) in amniotic fluid (AF) and serum of pregnancies with acute toxoplasmosis, Southern Brazil. It also was compared the levels of the same mediators in the serum of pregnancies in acute and chronic toxoplasmosis with non-infected. Serological investigation, anti-T gondii IgM and IgG, of the 67 pregnancies was determined by Elisa MEIA. Forty two were uninfected, eight in chronic phase and 17 in acute phase. Among the acute phase, seven agreed to amniocentesis. The cytokines, in serum and in AF, were assessed by sandwich ELISA, and NO was estimated from the nitrite measurement with Griess reagent. The IFN-γ and TGF-ß levels in the AF and blood were similar, while TNF-α levels was lower in the AF. On the other hand, NO was higher in the AF. Chronically infected pregnant women have showed lower levels of INF-γ than those in acute and uninfected pregnancies. The serological levels of TNF-α were lower in pregnancies with toxoplasmosis, when compared with non-infected. TGF-ß levels were higher in pregnancies in acute phase when compared with uninfected or chronically infected. NO in the serum of the infected had lower levels than those non-infected. In summary, higher concentrations of NO and lower levels of TNF-α were observed in the AF than in the serum of acute pregnancies, while TGF-ß e INF-γ levels were similar in both biological material. In the serum of infected pregnancies was observed decrease in inflammatory mediators and increase of TGF-ß.


Asunto(s)
Líquido Amniótico/metabolismo , Interferón gamma/sangre , Óxido Nítrico/sangre , Toxoplasmosis/sangre , Factor de Crecimiento Transformador beta/sangre , Factor de Necrosis Tumoral alfa/sangre , Brasil , Femenino , Humanos , Embarazo
14.
Undersea Hyperb Med ; 45(1): 27-32, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29571229

RESUMEN

INTRODUCTION: Necrosis, wound breakdown, and infection represent major complications associated with radical vulvectomy. We aimed to analyze the feasibility of hyperbaric oxygen (HBO2) therapy as an adjunctive treatment for such complications. METHODS: We performed a retrospective analysis of the medical records, clinical charts, and operative records of vulvar cancer patients who underwent hyperbaric oxygen therapy after extensive surgical resection in our institute between 2012 and 2016, with a comparison of the clinical outcomes of patients with similar surgical procedures andsevere wound complications who did not undergo HBO2. RESULTS: A total of 16 patients were included in the study. In the subgroup treated with HBO2, seven patients were identified. Two patients had primary surgery, while five had recurrent surgery (of these, two had previously undergone radiation therapy). Six patients received reconstructive flaps (five myocutaneous and onefasciocutaneous), while one patient had primary suture. Dehiscence, ischemia and necrosis were estimated to cover 30%-80% of the surgical surface area. Surgical debridement was performed in six patients. Daily 90-minute sessions in the hyperbaric chamber were performed at a pressure of 2.2 atmospheres absolute, with partial oxygen pressure of 1672 mbar. Infection control and satisfactory healing were achieved using 10-61 sessions. All patients in the subgroup who did not receive HBO2 required surgical debridement due to partial or near-total flap necrosis, with two reconstructive interventions required. CONCLUSIONS: Hyperbaric oxygen therapy was an efficient adjuvant for wound healing and infection control in managing wound complications after extensive vulvar resections.


Asunto(s)
Oxigenoterapia Hiperbárica/métodos , Complicaciones Posoperatorias/terapia , Neoplasias de la Vulva/cirugía , Vulvectomía/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada/métodos , Desbridamiento , Estudios de Factibilidad , Femenino , Humanos , Isquemia/terapia , Persona de Mediana Edad , Necrosis/terapia , Reoperación/efectos adversos , Estudios Retrospectivos , Colgajos Quirúrgicos , Herida Quirúrgica/patología , Herida Quirúrgica/terapia , Dehiscencia de la Herida Operatoria/terapia , Infección de la Herida Quirúrgica/terapia , Cicatrización de Heridas
15.
Physiol Mol Biol Plants ; 24(1): 99-114, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29398842

RESUMEN

Silicon (Si) frequently accumulates in plants tissues, mainly in roots of dicotyledons, such as cowpea. By contrast, Cadmium (Cd) is a metal that is extremely toxic to plant metabolism. This research aims to investigate if the deposition of Si in root can reduce Cd contents and minimize its negative effects on leaves, measuring gas exchange, chlorophyll fluorescence, antioxidant metabolism, photosynthetic pigments and growth, which may explain the possible role of Si in the attenuation of Cd toxicity in cowpea. This study had a factorial design, with all factors completely randomized and two Cd concentrations (0 and 500 µM Cd, termed as - Cd and + Cd, respectively) and three Si concentrations (0, 1.25 and 2.50 mM Si). Si reduced Cd contents in the roots and in other plant organs, such as stems and leaves. The Si contents were highest in roots, followed by stems and leaves, which was explained by the passive absorption of Si. The application of Si promoted increase in both the macro- and micronutrient contents in all tissues, suggesting that Si mitigates the effect of Cd on nutrient uptake. Si attenuated Cd-mediated effects on light absorption of photosystem II (PSII), increasing the effective quantum yield of PSII photochemistry and the electron transport rate. Additionally, toxic effects induced by Cd on gas exchange were mitigated by the action of Si. Plants treated with Cd + Si showed increase in the activities of antioxidant enzymes and reductions in oxidant compounds; these modifications were promoted by Si via detoxification mechanisms. Increases in the photosynthetic pigments and growth of plants treated with Si and exposed to Cd stress were detected and were due to the reduced deterioration of cell membranes and maintenance of chloroplasts, which had positive repercussions on growth and development. This study validated the hypothesis that the accumulation of Si in roots induces benefits on metabolism and alleviates the toxic effects caused by Cd in leaves of cowpea.

16.
Biomed Chromatogr ; 31(12)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28623841

RESUMEN

This study describes the development, validation and application of a high-performance liquid chromatography (HPLC) method for the simultaneous determination of the in vitro skin penetration profile of four UV filters on porcine skin. Experiments were carried out on a gel-cream formulation containing the following UV filters: diethylamino hydroxybenzoyl hexyl benzoate (DHHB), bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT), methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT) and ethylhexyl triazone (EHT). The HPLC method demonstrated suitable selectivity, linearity (10.0-50.0 µg/mL), precision, accuracy and recovery from porcine skin and sunscreen formulation. The in vitro skin penetration profile was evaluated using Franz vertical diffusion cells for 24 h after application on porcine ear skin. None of the UV filters penetrated the porcine skin. Most of them stayed on the skin surface (>90%) and only BEMT, EHT and DHHB reached the dermis plus epidermis layer. These results are in agreement with previous results in the literature. Therefore, the analytical method was useful to evaluate the in vitro skin penetration of the UV filters and may help the development of safer and effective sunscreen products.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Piel/química , Protectores Solares/análisis , Protectores Solares/metabolismo , Animales , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Piel/metabolismo , Absorción Cutánea , Protectores Solares/química , Protectores Solares/farmacocinética , Porcinos
17.
Skin Pharmacol Physiol ; 30(2): 81-89, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28319939

RESUMEN

BACKGROUND/AIM: The main reason for extrinsic skin aging is the negative action of free radicals. The formation of free radicals in the skin has been associated with ultraviolet (UV) exposure and also to visible (VIS) and near-infrared (NIR) irradiations. The aim of the present study was to evaluate the efficacy of a sunscreen in the whole solar range. METHODS: The radical-scavenging activity of a sunscreen in the UV, VIS, and NIR ranges was evaluated using electron paramagnetic resonance spectroscopy. Ex vivo penetration profiles were determined using confocal Raman microscopy on porcine ear skin at different time points after application. RESULTS: Compared to the untreated skin, the sunscreen decreased the skin radical formation in the UV and VIS regions. Additional protection in the VIS and NIR ranges was observed for the sunscreen containing antioxidants (AO). The penetration depth of the cream was less than 11.2 ± 3.0 µm for all time points. CONCLUSION: A sunscreen containing AO improved the photoprotection in the VIS and NIR ranges. The sunscreen was retained in the stratum corneum. Therefore, these results show the possibility of the development of effective and safer sunscreen products.


Asunto(s)
Antioxidantes/farmacología , Depuradores de Radicales Libres/farmacología , Piel/efectos de los fármacos , Protectores Solares/farmacología , Animales , Antioxidantes/administración & dosificación , Espectroscopía de Resonancia por Spin del Electrón , Depuradores de Radicales Libres/administración & dosificación , Radicales Libres/metabolismo , Piel/efectos de la radiación , Luz Solar/efectos adversos , Protectores Solares/administración & dosificación , Porcinos , Rayos Ultravioleta/efectos adversos
18.
AAPS PharmSciTech ; 18(6): 2110-2119, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28028794

RESUMEN

This study aimed (i) to prepare liquid crystalline systems (LCS) of glyceryl monooleate (GMO) and water containing antibacterial compounds and (ii) to evaluate their potential as drug delivery systems for topical treatment of bacterial infections. Therefore, LCS containing CPC (cetylpyridinium chloride) (LCS/CPC) and PHMB (poly(hexamethylene biguanide) hydrochloride) (LCS/PHMB) were prepared and the liquid crystalline phases were identified by polarizing light microscopy 24 h and 7 days after preparation. The in vitro drug release profile and in vitro antibacterial activity of the systems were assessed using the double layer agar diffusion method against Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, Escherichia coli, and Enterococcus faecalis. The interaction between GMO and the drugs was evaluated by a drug absorption study. Stable liquid crystalline systems containing CPC and PHMB were obtained. LCS/PHMB decreased the PHMB release rate and exerted strong antibacterial activity against all the investigated bacteria. In contrast, CPC interacted with GMO so strongly that it became attached to the system; the amount released was not sufficient to exert antibacterial activity. Therefore, the studied liquid crystalline systems were suitable to deliver PHMB, but not CPC. Accordingly, it was demonstrated that GMO interacts with each drug differently, which may interfere in the final efficiency of GMO/water LCS.


Asunto(s)
Antibacterianos , Bacterias , Sistemas de Liberación de Medicamentos/métodos , Glicéridos , Enfermedades Cutáneas Infecciosas/tratamiento farmacológico , Antibacterianos/administración & dosificación , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Antiinfecciosos/farmacología , Bacterias/clasificación , Bacterias/efectos de los fármacos , Liberación de Fármacos , Glicéridos/administración & dosificación , Glicéridos/química , Glicéridos/farmacología , Humanos , Cristales Líquidos/química , Reproducibilidad de los Resultados
19.
AAPS PharmSciTech ; 18(7): 2505-2516, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28213845

RESUMEN

Lipid nanoparticles have shown many advantages for treatment/prevention of skin disorders with damaged skin barrier function. Beeswax is a favorable candidate for the development of nanosystems in the cosmetic and dermatological fields because of its advantages for the development of products for topical application. In the present study, beeswax-based nanoparticles (BNs) were prepared using the hot melt microemulsion technique and incorporated to a gel-cream formulation. The formulation was subsequently evaluated for its rheological stability and effect on stratum corneum water content (SCWC) and transepidermal water loss (TEWL) using in vivo biophysical techniques. BNs resulted in mean particle size of 95.72 ± 9.63 nm and zeta potential of -9.85 ± 0.57 mV. BN-loaded formulation showed shear thinning behavior, well adjusted by the Herschel-Bulkley model, and a small thixotropy index that were stable for 28 days at different temperatures. BN-loaded formulation was also able to simultaneously decrease the TEWL and increase the SCWC values 28 days after treatment. In conclusion, the novel beeswax-based nanoparticles showed potential for barrier recovery and open the perspective for its commercial use as a novel natural active as yet unexplored in the field of dermatology and cosmetics for treatment of skin diseases with damaged skin barrier function.


Asunto(s)
Nanopartículas/química , Piel/metabolismo , Ceras/química , Administración Tópica , Adulto , Cosméticos , Composición de Medicamentos , Femenino , Humanos , Lípidos , Pomadas
20.
Int J Environ Health Res ; 26(5-6): 600-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27604245

RESUMEN

Toxoplasma gondii oocysts are an important form of contamination with a high dispersion in the environment, but their detection is still a challenge. This study evaluated the recovery of oocysts from strawberries and crisphead lettuce. Samples (250 g of strawberries or one head of lettuce) were experimentally inoculated with 10, 10(2), 10(3) and 10(4) T. gondii oocysts, by two separate processes, spot dripping and immersion. Then, 50 g of each sample was washed, filtered through a cellulose ester membrane, and concentrated by centrifugation. Three aliquots were taken for DNA extraction in a direct way, after freeze-thaw (FT) cycles or ultrasound (US), followed by PCR (B22-B23 and Tox4-Tox5 primers). The T. gondii DNA was amplified with the primers B22-B23 in all samples contaminated by dripping and when DNA extraction was carried out after FT or US. These techniques may be useful in epidemiological surveillance in the control of this zoonosis.


Asunto(s)
Parasitología de Alimentos/métodos , Frutas/parasitología , Lactuca/parasitología , Toxoplasma/aislamiento & purificación , Brasil , Fragaria/parasitología , Oocistos/citología , Hojas de la Planta/parasitología , Reacción en Cadena de la Polimerasa
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