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1.
Polymers (Basel) ; 16(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38337278

RESUMO

The essential role of active packaging is food quality improvement, which results in an extension of shelf life. Active packaging can also further enhance distribution from the origin point, and contributes to food waste reduction, offering greater sustainability. In this study, we introduced a new method for obtaining cellulose-based active packages, combining gamma irradiation as an eco-friendly activation process, and clove essential oil and cold-pressed rosehip seed oil as bioactive agents. Newly obtained bioactive materials were evaluated to assess their structural, hydrophobic, and morphological properties, thermal stability, and antioxidant and antimicrobial properties. The results showed that the plant oils induced their antimicrobial effects on paper, using both in vitro tests, against several bacterial strains (Gram-positive bacteria Listeria monocytogenes and Gram-negative bacteria Salmonella enteritidis and Escherichia coli), and in vivo tests, on fresh cheese curd and beef. Moreover, these oils can help control foodborne pathogens, which leads to extended shelf life.

2.
Materials (Basel) ; 16(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38005130

RESUMO

Particleboards with different combinations of the adhesive material imidazole, citric acid, and sorbitol were produced. Softwood sawdust from a Swedish sawmill was mixed with an aqueous solution of the chemicals and then dried to 0% moisture content prior to pressing. The boards were pressed to a target density of 700 kg m-3 at either 200 °C or 220 °C for 10 min. The hygroscopic and mechanical properties of the boards were clearly better at 220 °C than 200 °C for all used chemical combinations. A combination of imidazole (14.4 wt%) and citric acid (11.3 wt%) led to the best results, where the thickness swelling after 24 h of water immersion was 6.3% and the internal bonding strength was 0.57 MPa. The modulus of rupture and modulus of elasticity were 3.3 MPa and 1.1 GPa, respectively. Cyclic accelerated weathering showed exceptional stability with a thickness change after boiling and drying of only 2.1% compared to the initial dry thickness. This study indicates that the presence of imidazole leads to greatly improved hygroscopic properties and good internal bonding strength when used in particleboards.

3.
Science ; 379(6635): 892-901, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36862793

RESUMO

We elucidate grapevine evolution and domestication histories with 3525 cultivated and wild accessions worldwide. In the Pleistocene, harsh climate drove the separation of wild grape ecotypes caused by continuous habitat fragmentation. Then, domestication occurred concurrently about 11,000 years ago in Western Asia and the Caucasus to yield table and wine grapevines. The Western Asia domesticates dispersed into Europe with early farmers, introgressed with ancient wild western ecotypes, and subsequently diversified along human migration trails into muscat and unique western wine grape ancestries by the late Neolithic. Analyses of domestication traits also reveal new insights into selection for berry palatability, hermaphroditism, muscat flavor, and berry skin color. These data demonstrate the role of the grapevines in the early inception of agriculture across Eurasia.


Assuntos
Evolução Biológica , Domesticação , Vitis , Humanos , Agricultura , Ásia Ocidental , Ecótipo , Fenótipo , Vitis/genética , Aclimatação
4.
Med Ultrason ; 24(4): 393-398, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36047426

RESUMO

AIM: Contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS) parameters may be used to predict prognosis of pancreatic ductal adenocarcinoma (PDAC) and pancreatic neuroendocrine tumors (pNET). The aim of this study was to investigate the association between several perfusion parameters on CEH-EUS performed before treatment and survival outcome in patients with PDAC or pNET. MATERIAL AND METHODS: Thirty patients with PDAC or pNET who underwent CEH-EUS and EUS-guided fine needle aspiration (EUS-FNA) were included. Quantitative analysis of tumor vascularity was performed using time-intensity curve (TIC) analysis-derived parameters, obtained from processing CEH-EUS recordings with a commercially available software (VueBox). Cox proportional hazards models were used to determine associations with survival outcome. RESULTS: Median overall survival (OS) for PDAC patients was 9.61 months (95% CI: 0.1-38.7) while the median OS for pNET patients was 15.81 months (95% CI: 5.8-24.75. In a multivariate model for OS, a lower peak enhancement (HR=1.76, p=0.02) and a lower wash-in area under the curve (HR=1.06, p=0.001) were associated with worse survival outcome for patients with PDAC. CONCLUSIONS: CEH-EUS parameters may be used as a surrogate to predict PDAC aggressiveness and survival before treatment. After validation by large-scale studies, CEH-EUS perfusion parameters have the potential to be used in pretreatment risk stratification of patients with PDAC and in evidence-based clinical decision support.


Assuntos
Carcinoma Ductal Pancreático , Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Projetos Piloto , Tumores Neuroendócrinos/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/patologia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Perfusão , Estudos Retrospectivos , Neoplasias Pancreáticas
5.
Diagnostics (Basel) ; 12(7)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35885546

RESUMO

Endoscopic ultrasound (EUS) gained wide acceptance as the diagnostic and minimally invasive therapeutic approach for intra-luminal and extraluminal gastrointestinal, as well as various non-gastrointestinal lesions. Since its introduction, EUS has undergone substantial technological advances. This multi-centric study is a retrospective analysis of a prospectively maintained database of patients who underwent EUS for the evaluation of lesions located within the gastrointestinal tract and the proximal organs. It aimed to extensively assess in dynamic the dual-center EUS experience over the course of the past 20 years. Hence, we performed a population study and an overall assessment of the EUS procedures. The performance of EUS-FNA/FNB in diagnosing pancreatic neoplasms was evaluated. We also investigated the contribution of associating contrast-enhanced ultrasound imaging (CE-EUS) with EUS-FNA/FNB for differentiating solid pancreatic lesions or cystic pancreatic lesions. A total of 2935 patients undergoing EUS between 2002-2021 were included, out of which 1880 were diagnostic EUS and 1052 EUS-FNA/FNB (80% FNA and 20% FNB). Therapeutic procedures performed included endoscopic transmural drainage of pancreatic fluid collections, celiac plexus block and neurolysis, while diagnostic EUS-like CE-EUS (20%) and real-time elastography (12%) were also conducted. Most complications occurred during the first 7 days after EUS-FNA/FNB or pseudocyst drainage. EUS and the additional tools have high technical success rates and low rates of complications. The EUS methods are safe, cost effective and indispensable for the diagnostic or therapeutic management in gastroenterological everyday practice.

6.
Pharm Dev Technol ; 27(4): 389-398, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35468028

RESUMO

The focus of the current study is to investigate cholecalciferol (vitamin D3) solubilization by hydroxypropyl-ß-cyclodextrin (HPBCD) complexation through experimental and computational studies. Phase solubility diagram of vitamin D3 (completely insoluble in water) has an AP profile revealing a deviation from a linear regression with HPBCD concentration increase. Differential scanning calorimetry (DSC) is the best tool to confirm complex formation by disappearance of cholecalciferol exothermic peak in cholecalciferol-HPBCD complex thermogram, due to its amorphous state by entering HPBCD inner hydrophobic cavity, similarly validated by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). AP solubility diagram profile can be associated with cholecalciferol-HPBCD complex instability in liquid phase requiring spray drying to bring it to a solid dispersion state (always more stable) illustrated by scanning electron microscopy (SEM). Computational studies led to a deeper understanding and clarification, at molecular level, of the interactions within cholecalciferol-HPBCD complex. Thermodynamics and geometry of the complex were investigated by molecular dynamics (MD) simulation.


Assuntos
Simulação de Dinâmica Molecular , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina/química , Varredura Diferencial de Calorimetria , Colecalciferol , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X , beta-Ciclodextrinas/química
7.
Materials (Basel) ; 15(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35407682

RESUMO

Research on new conservation treatment for archaeological wood requires large amounts of wooden material. For this purpose, artificial wood degradation (biological-using brown-rot fungus Coniophora puteana, and chemical-using NaOH solution) under laboratory conditions was conducted to obtain an abundance of similar samples that mimic naturally degraded wood and can serve for comparative studies. However, knowledge about its properties is necessary to use this material for further study. In this study, the chemical composition and microstructure of degraded cell walls were investigated using FT-IR, XRD, helium pycnometry and nitrogen absorption methods. The results show that biological degradation caused the loss of hemicelluloses and celluloses, including the reduction in cellulose crystallinity, and led to lignin modification, while chemical degradation mainly depleted the amount of hemicelluloses and lignin, but also affected crystalline cellulose. These changes affected the cell wall microstructure, increasing both surface area and total pore volume. However, the chemical degradation produced a greater number of mesopores of smaller size compared to fungal decomposition. Both degradation processes weakened the cell wall's mechanical strength, resulting in high shrinkage of degraded wood during air-drying. The results of the study suggest that degraded wood obtained under laboratory conditions can be a useful material for studies on new consolidants for archaeological wood.

8.
Materials (Basel) ; 14(24)2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34947229

RESUMO

Large amounts of archaeological wood are often excavated during groundworks in cities and towns. Part of the unearthed artefacts is usually saved, conserved and then presented in museums. However, if the finding contains several similar objects, some of them could potentially be further employed for some other practical purposes. The research aimed to determine the mechanical performance of the remains of wooden water mains excavated at Bóznicza street in Poznan, Poland and evaluate its potential usefulness for any practical purposes. First, wood density was determined along with its mechanical strength in compression. The density of archaeological wood identified as Scots pine was lower than contemporary pinewood (383 kg × m-3 vs. 572 kg × m-3); therefore, its mechanical properties in compression tests were also lower, as expected, making the wood unsuitable for any practical applications. However, the differences in modulus of elasticity and compressive strength were not justified by the differences in wood density. Further infrared spectroscopy and X-ray diffraction analyses revealed additional differences in chemical composition and cellulose crystallinity between archaeological and contemporary wood. The results indicated the decrease in carbohydrate content and cellulose crystallinity in degraded wood, which, in addition to wood density, apparently contribute to the deterioration in mechanical strength of archaeological wood. The case study of the excavated archaeological wooden pipes shows that they have historical value but are not useful for practical purposes. It also revealed that not only wood density but also its chemical composition and cellulose crystallinity level has a substantial impact on the wood mechanical properties, particularly in compression.

9.
Exp Ther Med ; 22(4): 1150, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34504595

RESUMO

Despite many advances in the latest period, lung cancer remains the cancer with the highest mortality. The latest developments concerning lung cancer treatment have changed the clinical practice by prolonging patient survival; however, unfortunately, there remains a high mortality rate firstly due to disease aggressivity and secondly through lack of early diagnosis and screening programs. Currently, researchers and clinicians are talking about personalized cancer treatment, and a complete diagnostic evaluation should consider, in addition to staging and histology, molecular aberrations, and genetics of the tumor tissue. The development of tyrosine kinase inhibitors (TKIs) has led to an improvement in survival for patients with EGFR mutations, this being the most studied driver mutation in adenocarcinoma; and at the same time an important predictive factor for patient outcome following the treatment with TKIs. Reseach must investigate the different TKI combination strategies in order to overcome resistance and to increase patient survival. Currently, there are ongoing clinical trials that will probably change the therapeutic approach for EGFR-mutated advanced or metastatic NSCLC patients.

10.
PLoS One ; 16(6): e0251701, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34181680

RESUMO

Differential diagnosis of focal pancreatic masses is based on endoscopic ultrasound (EUS) guided fine needle aspiration biopsy (EUS-FNA/FNB). Several imaging techniques (i.e. gray-scale, color Doppler, contrast-enhancement and elastography) are used for differential diagnosis. However, diagnosis remains highly operator dependent. To address this problem, machine learning algorithms (MLA) can generate an automatic computer-aided diagnosis (CAD) by analyzing a large number of clinical images in real-time. We aimed to develop a MLA to characterize focal pancreatic masses during the EUS procedure. The study included 65 patients with focal pancreatic masses, with 20 EUS images selected from each patient (grayscale, color Doppler, arterial and venous phase contrast-enhancement and elastography). Images were classified based on cytopathology exam as: chronic pseudotumoral pancreatitis (CPP), neuroendocrine tumor (PNET) and ductal adenocarcinoma (PDAC). The MLA is based on a deep learning method which combines convolutional (CNN) and long short-term memory (LSTM) neural networks. 2688 images were used for training and 672 images for testing the deep learning models. The CNN was developed to identify the discriminative features of images, while a LSTM neural network was used to extract the dependencies between images. The model predicted the clinical diagnosis with an area under curve index of 0.98 and an overall accuracy of 98.26%. The negative (NPV) and positive (PPV) predictive values and the corresponding 95% confidential intervals (CI) are 96.7%, [94.5, 98.9] and 98.1%, [96.81, 99.4] for PDAC, 96.5%, [94.1, 98.8], and 99.7%, [99.3, 100] for CPP, and 98.9%, [97.5, 100] and 98.3%, [97.1, 99.4] for PNET. Following further validation on a independent test cohort, this method could become an efficient CAD tool to differentiate focal pancreatic masses in real-time.


Assuntos
Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Diagnóstico por Computador/métodos , Diagnóstico Diferencial , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Endossonografia/métodos , Humanos , Redes Neurais de Computação , Neoplasias Pancreáticas/patologia , Projetos Piloto , Sensibilidade e Especificidade
11.
Gastrointest Endosc ; 93(5): 1142-1151.e2, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33058885

RESUMO

BACKGROUND AND AIMS: EUS-guided FNA is recommended as a first-line procedure for the histopathologic diagnosis of pancreatic cancer. Molecular analysis of EUS-FNA samples might be used as an auxiliary tool to strengthen the diagnosis. The current study aimed to evaluate the diagnostic performances of K-ras testing using droplet digital polymerase chain reaction (ddPCR) and a novel single-nucleotide variant (SNV) assay performed on pancreatic EUS-FNA samples. METHODS: EUS-FNA specimens from 31 patients with pancreatic masses (22 pancreatic ductal adenocarcinomas, 7 chronic pancreatitis, and 2 pancreatic neuroendocrine tumors) were included in the study. K-ras testing was initially performed by ddPCR. In addition, mutational status was evaluated using an SNV assay by NanoString technology, using digital enumeration of unique barcoded probes to detect 97 SNVs from 24 genes of clinical significance. RESULTS: The overall specificity and sensitivity of cytologic examination were 100% and 63%, respectively. K-ras mutation testing was performed using ddPCR, and the sensitivity increased to 87% with specificity 90%. The SNV assay detected at least 1 variant in 90% of pancreatic ductal adenocarcinoma samples; the test was able to detect 2 K-ras codon 61 mutations in 2 cases of pancreatic ductal adenocarcinoma, which were missed by ddPCR. The overall diagnostic accuracy of the cytologic examination alone was 74%, and it increased to 91% when the results of both molecular tests were considered for the cases with negative and inconclusive results. CONCLUSIONS: The current study illustrated that integration of K-ras analysis with cytologic evaluation, especially in inconclusive cases, can enhance the diagnostic accuracy of EUS-FNA for pancreatic lesions.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Endossonografia , Humanos , Nucleotídeos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
12.
Materials (Basel) ; 13(13)2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32605199

RESUMO

Biobased materials present a great interest due to their properties and biodegradability. Cellulose nanocrystals (CNC) nanofiller, in various amounts, was incorporated into a carboxymethyl cellulose (CMC)-glycerol (G) matrix in order to obtain nanocomposite systems with improved properties. The effect of the nanofiller on the structural features was investigated by Fourier transform infrared (FT-IR) spectroscopy, principal component analysis (PCA), two-dimensional correlation spectroscopy (2D-COS), and X-ray diffraction, while the sorption properties were evaluated by water vapor isotherms using the gravimetric method coupled with infrared spectroscopy. We observed the presence of the interactions taking place between the CMC-G and CNC involving the hydroxyl and carboxylate groups, which decreased the number of water sorption sites. Following this, the moisture content in the nanocomposite films decreased with the increase in the amount of CNC. Moreover, the bands associated to water molecules presented different wavenumber values separated for CMC-G and CNC components.

13.
Endosc Ultrasound ; 9(2): 116-121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32295969

RESUMO

BACKGROUND: Recent advances in EUS techniques (real-time EUS elastography and contrast-enhanced EUS) have allowed a better characterization of focal pancreatic masses. Mean strain histograms (SHs) are considered a good parameter for the semi-quantitative evaluation of focal pancreatic masses, alongside complementary contrast-enhanced EUS parameters which can be quantified during both the early arterial and late venous phase. MATERIALS AND METHODS: The study design was prospective, blinded, and multicentric, assessing real-time EUS elastography and contrast-enhanced EUS results for the characterization of focal pancreatic masses using parametric measurements, in comparison with pathology which is the gold standard. SHs were performed based on the embedded software of the ultrasound system, with the values being reversed as opposed to our initially published data on hue histograms. Consequently, a cutoff of 80 was derived from previous multicentric trials. Contrast-enhanced EUS also allowed the focal masses to be classified as hyper-, iso-, or hypoenhanced in comparison with the normal pancreatic parenchyma. EUS-FNA was then performed for all patients, with a positive cytological diagnosis taken as a final proof of malignancy for the pancreatic masses. The diagnoses obtained by EUS-FNA were verified further either by surgery or during a clinical follow-up of at least 6 months. RESULTS: A total number of 97 consecutive patients with focal pancreatic masses were included in the study. Based on previously defined cutoffs of 80, the values of sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the mean SHs for the diagnosis of pancreatic cancer were 100%, 29.63%, 78.65%, 100%, and 80.41%, respectively. Corresponding values for contrast-enhanced EUS (taking into consideration hypoenhencement as a predictive factor of malignancy) were 98.57%, 77.78%, 92%, 95.45%, and 92.78%, respectively. Combining contrast enhancement-EUS (hypoenhencement) and semi-quantitative EUS elastography (SH cutoffs <80), the resulting values corresponding for sensitivity, specificity, and accuracy were 98.57%, 81.48%, and 93.81%, respectively. CONCLUSION: The current study using objective parametric tools for both EUS elastography and contrast-enhanced EUS confirmed the results of previous studies and meta-analyses that indicated a complementary role for the differential diagnosis of focal pancreatic masses. Moreover, the best values for the receiver operating curves were obtained using a sequential clinical algorithm based on the initial use of elastography, followed by contrast enhancement.

14.
Sci Rep ; 10(1): 2188, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32042023

RESUMO

Ineffectiveness of the chemicals applied so far for waterlogged wood conservation created the need to develop new more, efficient and reliable agents. As an alternative, a new method with the use of organosilicon compounds differing in chemical composition and molecular weight has been investigated. The results obtained show the potential of organosilicons as consolidants in waterlogged wood conservation able to effectively stabilise wood dimensions upon drying. The best wood stabilisers were low-molecular organosilicons enable to penetrate the cell wall as well as chemicals with functional groups capable of interacting with wood polymers and forming stabilising coatings on the cell wall surface. The best anti-shrink efficiency values were obtained for (3-Mercaptopropyl)trimethoxysilane, (3-Aminopropyl)triethoxysilane, 1,3-Bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, reaching 98, 91 and 91%, respectively. Most of the applied organosilicons reduced wood hygroscopicity, which limits the risk of further dimensional changes of wood exposed to a variable air moisture content and potentially reduces wood biodegradation. In the light of our studies, the proposed method of waterlogged wood conservation with organosilicons is potentially reversible in the case of siloxanes and amino-silanes as well as retreatable, which complies with the requirements of the conservation ethics.

15.
Int J Biol Macromol ; 145: 586-593, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31883886

RESUMO

Fibreboards are made of lignocellulosic fibres and synthetic adhesive which connect them. These synthetic adhesives, while relatively low-cost, are usually non-biodegradable and may cause health and environmental issues. Therefore, in recent years, there has been an increased demand for replacing these adhesives with bio-derived adhesives. The present study aims to develop fibreboards from chemo-thermomechanical pulp (CTMP) and a furanic resin based on prepolymers of furfuryl alcohol via wet-processing. To improve the bonding properties, maleic acid, aluminium sulphate, and cellulose nanocrystals (CNCs) were added. The resulting fibreboards were evaluated for their structural features and mechanical properties. The bending strength was improved when CNCs were added into the fibre's suspension, and the morphology indicated a more compact structure. The combination of the CTMP with CNC and Biorez resulted in the same mechanical behaviours as those noted for CTMP alone, the best performance being observed for the boards in which Al2(SO4)3 was added. Infrared spectroscopy and X-ray diffraction also proved the presence of cellulose nanocrystals and resin in the boards by increased specific bands intensity and crystallinity index, respectively.


Assuntos
Celulose/química , Fenômenos Químicos , Nanopartículas/química , Resinas Vegetais/química , Estrutura Molecular , Nanopartículas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Difração de Raios X
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 209: 280-287, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30414577

RESUMO

Wood has been extensively used as a material for different applications over the years, therefore the understanding of different degradation processes in various environments is of great importance. In this study, the infrared spectroscopy, X-ray diffraction and chemometric methods were used to evaluate and compare the structure of archaeological and artificially degraded oak wood. The results clearly show that modifications in the structure of archaeological wood are related to the position of the material in the log (sapwood and heartwood), thus the extent of wood degradation. To identify the possible factors influencing these effects, the control wood samples were exposed to artificial white rot biodegradation with Coriolus (Trametes) versicolor and to alkali treatment (with NaOH solution). Due to the structural similarities between biodegraded wood and control or archaeological samples, this type of decay is likely to occur during natural ageing along with degradation produced by other environmental factors. Further, no real similarity was identified between the alkali treated wood and archaeological samples, indicating that such degradation does not affect wood under natural conditions.


Assuntos
Arqueologia , Basidiomycota/metabolismo , Biodegradação Ambiental , Quercus/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Madeira/metabolismo , Difração de Raios X/métodos , Hidróxido de Sódio/química , Trametes/química
17.
AAPS PharmSciTech ; 19(3): 1358-1366, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29352403

RESUMO

The following research study focuses on improving the solubility of zaleplon (BCS class II drug) via micronization technique in order to enhance its oral delivery in orodispersible formulations. Zaleplon along with a surfactant solution was micronized by ultrasonication. The micronization process reduced the particle size of the crystalline drug about six-fold from its original size of 155.5 µm. The micronized zalepon dispersion was lyophilized to allow for a change in the state of matter (to a powder). The superior dissolution parameters (Q5, Q30, IDR, MDR, MDT, DE, and RDR) of zaleplon in microcrystalline form over the original crystalline form in in vitro dissolution studies had unraveled that micronization technique is an efficient tool in enhancing drug solubility. The micronized zaleplon solid dispersion (after lyophilization) was loaded into orodispersible tablet (ODT) and orodispersible film (ODF) formulations. The positive quality of ODT with adequate hardness and smooth texture was attributing to the presence of Pearlitol Flash® as a ready to use ODT platform. On the other hand, the ODF loaded with micronized zaleplon and prepared with Lycoat® RS 720 (as a film former) ensured adequate tensile strength. The disintegration time of ODT and ODF was 30 ± 5 and 35 ± 5 s, respectively. Thus, the orodispersible formulations containing micronized zaleplon have a strong potential for rapid disintegration following superior absorption in solution state through oral cavity into the blood stream, envisaging better oral delivery.


Assuntos
Acetamidas/química , Acetamidas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Pirimidinas/química , Pirimidinas/metabolismo , Acetamidas/administração & dosagem , Administração Oral , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/química , Anticonvulsivantes/metabolismo , Composição de Medicamentos/métodos , Dureza , Tamanho da Partícula , Pirimidinas/administração & dosagem , Solubilidade , Comprimidos/química , Resistência à Tração , Difração de Raios X/métodos
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 191: 405-412, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29065332

RESUMO

Spruce wood samples were subjected to different conditions of thermal and hydro-thermal treatment by varying the temperature, relative humidity and period of exposure. The obtained treated samples were evaluated using near infrared spectroscopy (NIR), principal component analysis (PCA) and hierarchical cluster analysis (HCA) in order to evidence the structural changes which may occur during the applied treatment conditions. Following this, modification in all wood components were observed, modifications which were dependent on the temperature, amount of relative humidity and also the treatment time. Therefore, higher variations were evidenced for samples treated at higher temperatures and for longer periods. At the same time, the increase in the amount of water vapours in the medium induced a reduced rate of side chains and condensation reactions occurring in the wood structure. Further, by PCA and HCA was possible to discriminate the modifications in the wood samples according to treatment time and amount of relative humidity.


Assuntos
Análise de Componente Principal , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Temperatura , Água/química , Madeira/química , Análise por Conglomerados , Picea/química
19.
AAPS PharmSciTech ; 18(2): 283-292, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27357420

RESUMO

The aim of this study is to develop an orally disintegrating film (ODF) containing a microparticulate measles vaccine formulation for buccal delivery. The measles vaccine microparticles were made with biocompatible and biodegradable bovine serum albumin (BSA) and processed by spray drying. These vaccine microparticles were incorporated in the ODF, consisting of Lycoat RS720®, Neosorb P60W® and Tween 80. The yield of the microparticles was approximately 85-95%, w/w. The mean size of the vaccine microparticles was 3.65 ± 1.89 µm and had a slightly negative surface charge of 32.65 ± 2.4 mV. The vaccine particles were nontoxic to normal cells at high concentrations (500 µg/2.5 × 105 cells) of vaccine particles. There was a significant induction of innate immune response by vaccine microparticles which was observed in vitro when compared to blank microparticles (P < 0.05). The vaccine microparticles also significantly increased the antigen presentation and co-stimulatory molecules expression on antigen presenting cells, which is a prerequisite for Th1 and Th2 immune responses. When the ODF vaccine formulation was dosed in juvenile pigs, significantly higher antibody titers were observed after week 2, with a significant increase at week 4 and plateauing through week 6 comparative to naïve predose titers. The results suggest that the ODF measles vaccine formulation is a viable dosage form alternative to noninvasive immunization that may increase patient compliance and commercial distribution.


Assuntos
Vacina contra Sarampo/administração & dosagem , Vacina contra Sarampo/química , Mucosa Bucal/metabolismo , Administração Bucal , Administração Oral , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Imunização/métodos , Camundongos , Microesferas , Tamanho da Partícula , Soroalbumina Bovina/química , Suínos
20.
Med Ultrason ; 18(1): 18-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26962549

RESUMO

AIMS: It is well known that endoscopic ultrasound guided fine needle aspiration (EUS-FNA) has a high sensitivity (over 85%) and specificity (100%) for diagnosis of pancreatic cancer. The aim of the study was to establish a EUS based clinical diagnostic algorithm in patients with pancreatic masses and negative cytopathology after EUS-FNA, based on previously published results and cut-offs of real-time elastographic (RTE) EUS and contrast-enhanced harmonic (CEH) EUS. MATERIAL AND METHODS: We included in the study a subgroup of 50 consecutive patients with focal pancreatic masses which underwent EUS examinations with negative EUS-FNA. RTE-EUS and CEH-EUS were performed sequentially in all patients. The sensitivity, specificity and accuracy of these methods were calculated separately. A clinical decision algorithm based on elastography followed by CEH was established. RESULTS: For the diagnosis of possible malignancy, the sensitivity, specificity and accuracy of RTE-EUS were: 97.7%, 77.4%, and 84% respectively. CEH-EUS had similar results: 89.5%, 80.7%, and 84%, respectively. In 25 patients with soft/mixed appearance during elastography,sequential assessment using contrast-enhanced EUSwas performed. The specificity of CEH-EUS for detection of chronic pancreatitis in this sub-set of patients was excellent (100%). In other 25 patients with hard appearance in elastography (low strain) CEH-EUS had an excellent specificity (100%) and accuracy (93%) in the detection of pancreatic cancer. CONCLUSIONS: The proposed algorithm with sequential use of elastography followed by CEH could be a good clinical tool in the set of patients with negative EUS-FNA results for the differentiation between benign and malignant focal pancreatic masses.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Imagem Multimodal/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Fosfolipídeos , Hexafluoreto de Enxofre , Adolescente , Adulto , Idoso , Sistemas Computacionais , Meios de Contraste , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
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