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1.
Am J Otolaryngol ; 45(1): 104072, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37801745

RESUMO

PURPOSE: To compare outcomes of two different methods of meatoplasty following Canal Wall-Down tympanomastoidectomy. METHODS: A retrospective case review study of 48 patients with non-complicated unsafe chronic suppurative otitis media candidate for post-auricular canal wall-down tympanomastoidectomy via a post-auricular approach at Otolaryngology department, Benha university hospitals from January 2021 to January 2023, all were operated for the first time, and divided into 2 groups each of 24 patients. Group A submitted for classic 'Fisch', and group B 'Corner-Tag' meatoplasty. RESULTS: The mean age was 28.88 ± 13.26 years in group A and 33.33 ± 16.04 years in group B. Only one patient (4.2 %) in each group developed wound infection and none in both groups developed perichondritis. Two patients (8.3 %) in group B compared to only one patient (4.2 %) in group A had granulations on the meatal incision. One patient (4.2 % of group A) needed revision meatoplasty. Group B needed more time for epithelization (mean 7.33 ± 0.96 weeks) than group A (mean 6.5 ± 0.88 weeks; P = 0.003*) also resulted in wider mean new meatus in group B (mean 10.50 ± 1.02 mm) than in group A (mean 9.63 ± 1.41 mm; P = 0.02*). CONCLUSION: Both techniques had comparable post-operative complications. 'Corner-Tag' technique needed more time for healing and epithelization but gave a wider new meatal diameter than 'Fisch' meatoplasty after one year of follow-up.


Assuntos
Otite Média , Procedimentos de Cirurgia Plástica , Humanos , Adolescente , Adulto Jovem , Adulto , Estudos Retrospectivos , Processo Mastoide/cirurgia , Meato Acústico Externo/cirurgia , Mastoidectomia , Otite Média/cirurgia
2.
Biosci Biotechnol Biochem ; 79(6): 997-1004, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25562396

RESUMO

Ionizing radiation and oxidizing agent like H2O2 were used to degrade chitosan (CS) and its derivatives; N-maleoylchitosan (NMCS), and N-phthaloylchitosan (NPhCS). The structure changes were detected using gel permeation chromatography (GPC). The results revealed that ionizing radiation degraded CS, MNCS, NPhCS and altered their molecular weights and antioxidant activity. The higher the irradiation dose, the lower the molecular weight and the higher antioxidant activity. The addition of irradiated CS and NMCS to minced chicken resulted in highly significant reduction in malondialdehyde (MDA) content (50 and 70%, respectively) if compared with the control. The irradiated NMCS toxicity study did not show strong proliferative effect at small concentrations or cytotoxic effects at higher concentrations. The obtained results suggested that CS and NMCS could be used as natural antioxidant for improving the oxidative deterioration of minced chicken during refrigerated storage.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Galinhas , Quitosana/química , Quitosana/farmacologia , Manipulação de Alimentos , Raios gama , Animais , Células CACO-2 , Quitosana/análogos & derivados , Armazenamento de Alimentos , Humanos , Oxirredução , Solubilidade , Água/química
3.
Biomacromolecules ; 14(3): 688-98, 2013 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-23414209

RESUMO

The aim of this study was to improve the stability and bioavailability of pilocarpine in order to maintain an adequate concentration of the pilocarpine at the site of action for prolonged period of time. Thus, pH-sensitive polyvinylpyrrolidone-poly(acrylic acid) (PVP/PAAc) nanogels prepared by γ radiation-induced polymerization of acrylic acid (AAc) in an aqueous solution of polyvinylpyrrolidone (PVP) as a template polymer were used to encapsulate pilocarpine. Factors affecting size and encapsulation efficiency were optimized to obtain nanogel suitable for entrapping drug efficiently. The PVP/PAAc nanogel particles were characterized by dynamic light scattering (DLS), zeta potential, Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM), and their size can be controlled by the feed composition and concentration as well as the irradiation dose. Pilocarpine was loaded into the nanogel particles through electrostatic interactions where the AAc-rich nanogels exhibited the highest loading efficiency. The transmittance, mucoadhesion, and rheological characteristics of the nanogel particles were studied to evaluate their ocular applicability. The in vitro release study conducted in simulated tear fluid showed a relatively long sustained release of pilocarpine from the prepared PVP/PAAc nanogel particles if compared with pilocarpine in solution.


Assuntos
Resinas Acrílicas/química , Raios gama , Pilocarpina/farmacocinética , Polietilenoglicóis/química , Polietilenoimina/química , Povidona/química , Materiais Biocompatíveis/farmacocinética , Disponibilidade Biológica , Glaucoma/tratamento farmacológico , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Mucinas/metabolismo , Nanogéis , Tamanho da Partícula , Pilocarpina/química , Polímeros/química , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Cancer Inform ; 22: 11769351231171743, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200943

RESUMO

Abnormal miRNA expression has been evidenced to be directly linked to HCC initiation and progression. This study was designed to detect possible prognostic, diagnostic, and/or therapeutic miRNAs for HCC using computational analysis of miRNAs expression. Methods: miRNA expression datasets meta-analysis was performed using the YM500v2 server to compare miRNA expression in normal and cancerous liver tissues. The most significant differentially regulated miRNAs in our study undergone target gene analysis using the mirWalk tool to obtain their validated and predicted targets. The combinatorial target prediction tool; miRror Suite was used to obtain the commonly regulated target genes. Functional enrichment analysis was performed on the resulting targets using the DAVID tool. A network was constructed based on interactions among microRNAs, their targets, and transcription factors. Hub nodes and gatekeepers were identified using network topological analysis. Further, we performed patient data survival analysis based on low and high expression of identified hubs and gatekeeper nodes, patients were stratified into low and high survival probability groups. Results: Using the meta-analysis option in the YM500v2 server, 34 miRNAs were found to be significantly differentially regulated (P-value ⩽ .05); 5 miRNAs were down-regulated while 29 were up-regulated. The validated and predicted target genes for each miRNA, as well as the combinatorially predicted targets, were obtained. DAVID enrichment analysis resulted in several important cellular functions that are directly related to the main cancer hallmarks. Among these functions are focal adhesion, cell cycle, PI3K-Akt signaling, insulin signaling, Ras and MAPK signaling pathways. Several hub genes and gatekeepers were found that could serve as potential drug targets for hepatocellular carcinoma. POU2F1 and PPARA showed a significant difference between low and high survival probabilities (P-value ⩽ .05) in HCC patients. Our study sheds light on important biomarker miRNAs for hepatocellular carcinoma along with their target genes and their regulated functions.

5.
Gene ; 769: 145237, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33127537

RESUMO

Egyptians are at a crossroad between Africa and Eurasia, providing useful genomic resources for analyzing both genetic and environmental factors for future personalized medicine. Two personal Egyptian whole genomes have been published previously by us and here nine female whole genome sequences with clinical information have been added to expand the genomic resource of Egyptian personal genomes. Here we report the analysis of whole genomes of nine Egyptian females from different regions using Illumina short-read sequencers. At 30x sequencing coverage, we identified 12 SNPs that were shared in most of the subjects associated with obesity which are concordant with their clinical diagnosis. Also, we found mtDNA mutation A4282G is common in all the samples and this is associated with chronic progressive external ophthalmoplegia (CPEO). Haplogroup and Admixture analyses revealed that most Egyptian samples are close to the other north Mediterranean, Middle Eastern, and European, respectively, possibly reflecting the into-Africa influx of human migration. In conclusion, we present whole-genome sequences of nine Egyptian females with personal clinical information that cover the diverse regions of Egypt. Although limited in sample size, the whole genomes data provides possible geno-phenotype candidate markers that are relevant to the region's diseases.


Assuntos
Biologia Computacional , Genoma Humano , Filogeografia , Adulto , DNA Mitocondrial/genética , Egito , Feminino , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma
6.
Mater Sci Eng C Mater Biol Appl ; 110: 110726, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32204037

RESUMO

The present work reports a nanotechnology strategy to prepare a low-viscosity poly(acrylic acid) (PAAc)-based tear substitute with enhanced efficacy and compliance. Specifically, nanogels composed of PAAc and polyvinylpyrrolidone (PVP) were prepared by adapting an ionizing radiation method. For this purpose, different aqueous systems: PVP/PAAc nanoparticulate complexes, PVP/acrylic acid (AAc), N-vinylpyrrolidone (N-VP)/PAAc, and N-VP/AAc were exposed to gamma rays. The dynamic light scattering technique showed that stable nanogels are only produced in a relatively high yield from the PVP/AAc system. Nanogel formation was driven by the hydrogen-bonding complexation between PVP and PAAc (formed in situ) as well as the radiation-induced cross-linking. Transparency, viscosity and mucoadhesiveness of emerged nanogels were optimized by controlling the feed composition and irradiation dose. Furthermore, neutralized nanogels were topically applied in a dry eye model and compared with a PAAc-based commercial tear substitute, namely Vidisic® Gel. The results of Schirmer's test and tear break-up time demonstrated that nanogels prepared from AAc-rich feed solutions at 20 kGy enhanced markedly the dry eye conditions. The histopathological analysis also ensured the competence of PAAc-rich nanogels to completely return the corneal epithelium to its normal state.


Assuntos
Resinas Acrílicas , Materiais Biomiméticos , Síndromes do Olho Seco/tratamento farmacológico , Hidrogéis , Lubrificantes Oftálmicos , Resinas Acrílicas/química , Resinas Acrílicas/farmacologia , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Modelos Animais de Doenças , Síndromes do Olho Seco/metabolismo , Hidrogéis/química , Hidrogéis/farmacologia , Lubrificantes Oftálmicos/química , Lubrificantes Oftálmicos/farmacologia , Coelhos , Viscosidade
7.
J Hazard Mater ; 159(2-3): 372-9, 2008 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-18367330

RESUMO

Study has been made on the preparation of functionalized copolymer by grafting N,N-(dimethylaminoethyl) methacrylate (DMAEMA) onto polypropylene (PP) films using gamma-irradiation technique. The effect of monomer concentration and irradiation dose on the grafting yield was studied. It was found that grafting yield increases with increasing the monomer concentration and irradiation dose. Subsequent quaternization of the amine group of PDMAEMA graft chain using different reagents, 1-bromo octadecane, methyl iodide and benzyl chloride, to improve their ionic character was carried out. The grafted PP films were characterized by IR spectroscopy, and mechanical and thermal properties. During the adsorption of phosphate (PO(4)(3-)) and nitrate (NO(3)(-)) ions, the rate of adsorption, pH effect, desorbability and initial feed concentration effect were investigated. It was found that the adsorption of PO(4)(3-) and NO(3)(-) ions increases with increasing the adsorption time up to 10h and decreases with increasing the pH of medium. The desorbability is ranging from 18 to 30%, and it is relatively difficult to desorb PO(4)(3-) and NO(3)(-) ions from the functionalized grafted copolymers. Results showed good possibility for the use of such functionalized grafted film in the field of removal of some anions such as PO(4)(3-) and NO(3)(-) from their media.


Assuntos
Metacrilatos/química , Nitratos/química , Fosfatos/química , Adsorção , Concentração de Íons de Hidrogênio , Nitratos/isolamento & purificação , Fosfatos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Termogravimetria
8.
J Biomed Mater Res B Appl Biomater ; 81(1): 168-74, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16924606

RESUMO

pH-sensitive hydrogels were prepared from poly(ethylene glycol) (PEG) and acrylic acid (AAc) in aqueous solution employing gamma-radiation-induced copolymerization and crosslinking. The swelling behavior of the prepared hydrogels was determined by investigating the time and pH-dependent swelling of the (PEG/AAc) hydrogels of different PEG content. The effect of environmental parameters such as pH and ionic strength on the swelling kinetics was studied. The results not only show the dependence of the swelling indices on the pH value of the swelling medium but also show a clear dependence of the diffusion coefficient on the ionic strength of the medium. To estimate the ability of the prepared copolymer to be used as a colon-specific drug carrier, the release of ketoprofen was studied as a function of time at pH 1 and pH 7.


Assuntos
Acrilatos/química , Portadores de Fármacos/química , Hidrogéis/síntese química , Polietilenoglicóis/química , Anti-Inflamatórios não Esteroides/química , Portadores de Fármacos/síntese química , Raios gama , Concentração de Íons de Hidrogênio , Cetoprofeno/química , Concentração Osmolar
9.
J Biomed Mater Res A ; 105(11): 3176-3188, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28707422

RESUMO

Poly(lactic acid) (PLA) has shown much success in the preparation of tissue engineering scaffolds as it can be fabricated with a tailored architecture. However, the PLA surface has drawbacks including the lack of biofunctional motifs which are essential for high affinity to biological cells. Therefore, this study describes a multistep physicochemical approach for the immobilization of d-glucosamine (GlcN), a naturally occurring monosaccharide having many biological functions, on the PLA surface aiming at enhancing the cell proliferation activity. In this approach, poly(acrylic acid) (PAAc) spacer arms are first introduced into the PLA surface via plasma post-irradiation grafting technique. Then, covalent coupling or physical adsorption of GlcN with/on the PAAc spacer is carried out. Factors affecting the grafting yield are controlled to produce a suitable spacer for bioimmobilization. X-ray photon spectroscopic (XPS) analyses confirm the immobilization of GlcN on the PLA surface. The XPS results reveal also that increasing the yield of grafted PAAc spacer on the PLA surface increases the amount of covalently immobilized GlcN, but actually inhibits the immobilization process using the physical adsorption method. Contact angle measurements and atomic force microscopy (AFM) show a substantial increase of surface energy and roughness of PLA surface, respectively, upon the multistep modification procedure. The cytocompatibility of the modified surfaces is assessed using a mouse embryonic fibroblast (MEF) cell line. Observation from the cell culture basically demonstrates the potential of GlcN immobilization in improving the cytocompatibility of the PLA surface. Moreover, the covalent immobilization of GlcN seems to produce more cytocompatible surfaces if compared with the physical adsorption method. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3176-3188, 2017.


Assuntos
Materiais Biocompatíveis/química , Glucosamina/química , Poliésteres/química , Adsorção , Animais , Linhagem Celular , Proliferação de Células , Fibroblastos/citologia , Cinética , Camundongos , Microscopia de Força Atômica , Propriedades de Superfície , Alicerces Teciduais/química
10.
Carbohydr Polym ; 176: 19-28, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28927598

RESUMO

Superabsorbent hydrogels based on polyacrylamide (PAAm) and Na-alginate (Alg) or chitosan (CS) were synthesized by γ-rays. The effect of dose and copolymer composition on gel content and water absorbency of PAAm/Alg, PAAm/CS and PAAm/Alg/CS hydrogels were studied. The gel content and water absorbency follows the order PAAm/Alg>PAAm/Alg/CS>PAAm/CS. The effect of different cations, fertilizers, buffers on water absorbency of the hydrogels was investigated. Water retention capability of swollen hydrogels as a function of time was studied. PAAm/Alg hydrogel has a high water retention capability. An application of the prepared hydrogels in agricultural fields was performed using maize plants. The results showed that the presence of hydrogels had growth promotion effect on quality and quantity of maize plants. The plants treated by PAAm/Alg hydrogels showed 50% increase in the grain yield suggesting their possible use as a soil conditioner and a water reservoir for plant-soil system.


Assuntos
Resinas Acrílicas/efeitos da radiação , Agroquímicos/química , Alginatos/química , Quitosana/química , Hidrogéis/química , Resinas Acrílicas/química , Peso Molecular , Zea mays/crescimento & desenvolvimento
11.
Int J Biol Macromol ; 50(2): 403-13, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22222149

RESUMO

Modification of chitosan (CS) to N-maleoylchitosan (NMCS), N-phthaloylchitosan (NPhCS) and sulfonated-chitosan (SCS) was done using maleic anhydride, phthalic anhydride and chlorosulfonic acid, respectively followed by exposing them to γ-rays at different doses. The molecular weights and structural changes of irradiated chitosan derivatives were determined by GPC, FT-IR and UV-vis spectrophotometer. The molecular weights decreased with increasing irradiation dose. Results revealed that the main polysaccharide structure remained after irradiation. To investigate the enhancement of antioxidant activity of chitosan and its derivatives of different molecular weights, radical mediated lipid peroxidation inhibition, scavenging effect of DPPH radicals, reducing power and ferrous ion chelating activity assays were used. Chitosan derivatives with different molecular weights exhibit antioxidant activity. The lower the molecular weights of chitosan and its derivatives, the higher the antioxidant activity. NMCS possessed high scavenging effect on DPPH radicals compared with NPhCS, SCS and ascorbic acid. The irradiated chitosan and its derivatives could be used as natural antioxidants.


Assuntos
Quitosana/química , Quitosana/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Radiação Ionizante , Configuração de Carboidratos/efeitos da radiação , Quitosana/síntese química , Sequestradores de Radicais Livres/síntese química , Radicais Livres/antagonistas & inibidores , Quelantes de Ferro/química , Quelantes de Ferro/farmacologia , Peso Molecular , Oxirredução/efeitos da radiação
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