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1.
Molecules ; 26(4)2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33672961

RESUMEN

Miscanthus is resistant to dry, frosty winters in Poland and most European Union countries. Miscanthus gives higher yields compared to native species. Farmers can produce Miscanthus pellets after drying it for their own heating purposes. From the third year, the most efficient plant development begins, resulting in a yield of 25-30 tons of dry matter from an area of 1 hectare. Laboratory scale tests were carried out on the processes of drying, compacting, and torrefaction of this biomass type. The analysis of the drying process was conducted at three temperature levels of the drying agent (60, 100, and 140 °C). Compaction on a hydraulic press was carried out in the pressure range characteristic of a pressure agglomeration (130.8-457.8 MPa) at different moisture contents of the raw material (0.5% and 10%). The main interest in this part was to assess the influence of drying temperature, moisture content, and compaction pressure on the specific densities (DE) and the mechanical durability of the pellets (DU). In the next step, laboratory analyses of the torrefaction process were carried out, initially using the Thermogravimetric Analysis TGA and Differential Scaning Calorimeter DSC techniques (to assess activation energy (EA)), followed by a flow reactor operating at five temperature levels (225, 250, 275, 300, and 525 °C). A SEM analysis of Miscanthus after torrefaction processes at three different temperatures was performed. Both the parameters of biochar (proximate and ultimate analysis) and the quality of the torgas (volatile organic content (VOC)) were analyzed. The results show that both drying temperature and moisture level will affect the quality of the pellets. Analysis of the torrefaction process shows clearly that the optimum process temperature would be around 300-340 °C from a mass loss ratio and economical perspective.


Asunto(s)
Biocombustibles , Desecación , Fertilizantes , Poaceae/química , Temperatura , Análisis de Varianza , Biomasa , Rastreo Diferencial de Calorimetría , Cinética , Tamaño de la Partícula , Poaceae/ultraestructura , Termogravimetría , Factores de Tiempo , Compuestos Orgánicos Volátiles/análisis , Volatilización
2.
Lasers Surg Med ; 50(4): 311-318, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29135033

RESUMEN

OBJECTIVE: The main goal was to compare the clinical data of patients with T1 and T2 glottic cancer treated with CO2 transoral laser microlaryngoscopy (TLM) in the Tertiary Referral University Department of Otolaryngology, Head Neck Surgery, Poznan and the local Department of Otolaryngology, Oncology and Maxillofacial Surgery, Bydgoszcz. MATERIAL AND METHODS: Unified databases for the 7-year period January 2005-December 2011 were created to compare these two cohorts. The database contained 341 patients: 231 from the tertiary center and 110 from the local department, of which 298 (87%) were men, and 43 (13%) were women. RESULTS: Cordectomy type I-IV was performed in 250 (73%) patients, cordectomy type V-VI in 84 (25%) patients, and cordectomy enlarged to epiglottic petiole in 7 (2%) patients. Local recurrence was observed in 96 (28%) cases. Among these cases, 81 (87.5%) patients had salvage surgery: 43 re-cordectomy, 10 open partial laryngectomy, and 28 total laryngectomy. The outcomes for the whole cohort, Tertiary Referral Center and Local Department respectively were as follows: larynx preservation rate was 91.8%, 93.6%, and 88%; 3-year disease specific survival was 97.4%, 97.9%, and 93.3%; 3-year overall survival was 93.5%, 96.6%, and 85.5%; 5-year disease specific survival was 95.2%, 95.2%, and 96.3%; and 5-year overall survival was 84.5%, 88.7%, and 76%, respectively. CONCLUSION: Comparison of the cohorts showed that outcomes of primary treatment were similar but there were noticeable differences in salvage treatment efficacy, favoring patients from the Tertiary Referral Center. Lasers Surg. Med. 50:311-318, 2018. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Glotis/cirugía , Neoplasias Laríngeas/mortalidad , Neoplasias Laríngeas/cirugía , Terapia por Láser/métodos , Terapia Recuperativa/métodos , Adulto , Anciano , Distribución de Chi-Cuadrado , Estudios de Cohortes , Bases de Datos Factuales , Supervivencia sin Enfermedad , Femenino , Glotis/patología , Hospitales Universitarios , Humanos , Neoplasias Laríngeas/patología , Laringectomía/métodos , Laringoscopía/métodos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Polonia , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Análisis de Supervivencia , Centros de Atención Terciaria
3.
Sci Rep ; 14(1): 4747, 2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413775

RESUMEN

Gram-negative spiral-shaped Helicobacter pylori (Hp) bacteria induce the development of different gastric disorders. The growing resistance of Hp to antibiotics prompts to search for new therapeutic formulations. A promising candidate is Mycobacterium bovis BCG (BCG) with immunomodulatory properties. Biodegradable mucoadhesive chitosan is a good carrier for delivering BCG mycobacteria to the gastric mucosal environment. This study aimed to show whether BCG bacilli are able to increase the phagocytic activity of Cavia porcellus-guinea pig macrophages derived from the bone marrow towards fluorescently labeled Escherichia coli. Furthermore, to encapsulate live BCG bacilli, in spray-dried chitosan microparticles (CHI-MPs), and assess the pH-dependent release of mycobacteria in pH conditions mimicking gastric (acidic) or gut (alkaline) milieu. Microparticles (MPs) were made of chitosan and coated with Pluronic F-127-(Plur) or N-Acetyl-D-Glucosamine-(GlcNAc) to increase the MPs resistance to low pH or to increase anti-Hp effect, respectively. Spray-drying method was used for microencapsulation of live BCG. The biosafety of tested CHI-MPs has been confirmed using cell models in vitro and the model of guinea pig in vivo. The CHI-MPs loaded with BCG released live mycobacteria at pH 3.0 (CHI-GlcNAc-MPs) or pH 8.0. (CHI-Plur-MPs). The CHI-MPs loaded with live BCG can be used for per os inoculation of Cavia porcellus to check the effectiveness of delivered mycobacteria in increasing anti-H. pylori host response.


Asunto(s)
Quitosano , Infecciones por Helicobacter , Helicobacter pylori , Mycobacterium bovis , Animales , Cobayas , Quitosano/química , Vacuna BCG , Concentración de Iones de Hidrógeno
4.
Int J Biol Macromol ; 222(Pt A): 473-486, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36184983

RESUMEN

The development of suitable drug delivery systems for prolonged action against HIV receives great attention in recent research. Herein, a long-acting injectable (LAI) of Tenofovir alafenamide-chitosan polymeric nanoparticles loaded oleogels developed with sesame oil and ethyl cellulose for prolonged release of the drug is reported for the first time. The research resulted with unique long-acting parenteral formulation for chronic anti-retroviral therapy, based on our experimental in-vitro and ex-vivo studies. The chitosan nanoparticles with 49 % drug content were produced through the spray-drying technique and characterized for their size (106-540 nm) and the other physico-chemical features through SEM, FT-IR, XRD, TGA, and DSC. The ethyl cellulose and sesame oil oleogels were developed through a heat-cool process by incorporating the drug-loaded chitosan nanoparticles. The oleogels exhibited extended release (56 %) of the drug for 16 days, which could be prolonged further to achieve the maximum drug release. Also, the ex-vivo permeation studies of the nanoparticles loaded oleogels demonstrated about 10-fold decrease in the flux and the permeation of the drug due to prolonged release of the drug across dual barriers of chitosan nanoparticles and ethyl cellulose gel matrix. The result provided proof-of-evidence that the developed Tenofovir alafenamide-chitosan polymeric nanoparticles loaded with ethyl cellulose oleogels could be potentially used as the long-acting injectable system for the treatment of patients infected with HIV/AIDS.


Asunto(s)
Fármacos Anti-VIH , Quitosano , Nanopartículas , Humanos , Quitosano/química , Fármacos Anti-VIH/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Aceite de Sésamo , Nanopartículas/química , Liberación de Fármacos , Adenina , Portadores de Fármacos/química , Tamaño de la Partícula , Sistemas de Liberación de Medicamentos
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