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1.
Eur Arch Otorhinolaryngol ; 271(8): 2185-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24081792

RESUMEN

In this study, high-resolution, multislice computed tomography findings are compared with surgical findings in terms of the fracture location in patients with traumatic facial paralysis. Patients with traumatic facial paralysis with grade VI House-Brackmann scale who met the criteria for surgical decompression between 2008 and 2012 were included in this study. All the patients underwent a multislice high-resolution, multislice computed tomography (HRCT) using 1-mm-thick slices with a bone window algorithm. The anatomical areas of the temporal bone (including the Fallopian canal) were assessed by CT and during the surgery (separately by the radiologist and the surgeon), and fracture line involvement was recorded. Forty-one patients entered this study. The perigeniculate area was the most commonly involved region (46.34 %) of the facial nerve. The sensitivity and specificity of HRCT to detect a fracture line seems to be different in various sites, but the overall sensitivity and specificity were 77.5 and 77.7 %, respectively. Although HRCT is the modality of choice in traumatic facial paralysis, the diagnostic value may differ according to the fracture location. The results of HRCT should be considered with caution in certain areas.


Asunto(s)
Traumatismos del Nervio Facial/diagnóstico por imagen , Tomografía Computarizada Multidetector , Fracturas Craneales/diagnóstico por imagen , Hueso Temporal/diagnóstico por imagen , Adolescente , Adulto , Anciano , Algoritmos , Niño , Preescolar , Descompresión Quirúrgica , Traumatismos del Nervio Facial/cirugía , Parálisis Facial/diagnóstico por imagen , Parálisis Facial/etiología , Parálisis Facial/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Fracturas Craneales/cirugía , Hueso Temporal/lesiones , Hueso Temporal/cirugía , Adulto Joven
2.
BMC Chem ; 18(1): 109, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831344

RESUMEN

Recently, there is a particular interest to utilize protic ionic liquids (PILs) in drug solubility. This study is exploring the effect of three protic ionic liquids (PILs) based on 2-hydroxyethylammonium carboxylate [2-hydroxyethylammonium acetate (MEAA), 2-hydroxyethylammonium lactate (MEAL), and 2-hydroxyethylammonium propionate (MEAP)] on the solubility of the very poorly soluble drug in water, indomethacin (IMC). The shake flask method was used to measure the experimental solubility of IMC at the different temperatures range (298.15-313.15) K. The results demonstrate significantly enhancment the solubility of IMC in PILs compared to pure water, with an approximate increase of 200 times. The experimental solubility data have been correlated using the empirical models which showed the performance as the order: Modified Apelblat-Jouyban-Acree > Van't Hoff-Jouyban-Acree > Modified Apelblat equations and also the performance for the Wilson model indicated as the order (absolute relative deviation): 2-hydroxyethylammonium acetate (3.030) > 2-hydroxyethylammonium propionate (3.239) > 2-hydroxyethylammonium lactate (7.665). Then the thermodynamic dissolution properties were obtained by usage of Gibbs and Van't Hoff equations to investigate the thermodynamic behavior of the IMC in the aqueous solution PILs. Eventually, the cytotoxicity of the co-solvents (PILs) under study was evaluated using a standard MTT assay. The results showed that the cell viability percentage increased in the following order: MEAA < MEAP < MEAL. These findings indicated that these PILs had low to moderate toxicity. It is noteworthy that the functional groups of the anions were not the only determinant factor of the cytotoxicity. Other factors encompassing concentration, exposure time, and cell line characteristics also had significant effects.

3.
BMC Chem ; 18(1): 136, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054553

RESUMEN

Absolute qualifications with the application of protic ionic liquids (PILs) and a recognition of the numerous thermophysical features of these materials are required in various processes. Due to the wonderful applications of these compounds and their high potential in the chemical and pharmaceutical industries, there is a particular eagerness to utilize these PILs in drug solubility and delivery area. The aim of this investigation was to explore the solubility of the acetaminophen (ACP) in three PILs base on ethanolamine laurate [(2-hydroxyethylammonium laurate [MEA]La), (bis(2-hydroxyethyl)ammonium laurate [DEA]La), and ( tris(2-hydroxyethyl)ammonium laurate [TEA]La)]. The shake flask method has been employed in this study, and the conditions were set at T = (298.15-313.15) K and atmospheric pressure. Moreover, the experimental solubility data was correlated using a variety of empirical and thermodynamic models, encompassing e-NRTL and Wilson activity coefficient models and the empirical models such as Van't Hoff-Jouyban-Acree and Modified Apelblat-Jouyban-Acree. Their performance for the system containing [MEA]La follow the trend for activity coefficient models and empirical respectively: the Wilson > e-NRTL and Modified Apelblat-Jouyban-Acree > Van't Hoff-Jouyban-Acree. On the other hand, [DEA]La and [TEA]La PILs followed slightly different trend for activity coefficient models and empirical respectively: the Wilson > e-NRTL and Van't Hoff-uyban-Acree > Modified Apelblat-Jouyban-Acree. The Van't Hoff and Gibbs equations were used to determine the thermodynamic properties of dissolution in the studied systems.

4.
Dent Mater ; 40(5): 858-868, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38616152

RESUMEN

OBJECTIVES: This study evaluates the potential for osseointegration and remodeling of customized dental implants made from Titanium-Hydroxyapatite Functionally Graded Material (Ti-HAP FGM) with optimized geometry, using the finite element method (FEM). METHODS: The study utilized CT scan images to model and assemble various geometrical designs of dental implants in a mandibular slice. The mechanical properties of Ti-HAP FGMs were computed by varying volume fractions (VF) of hydroxyapatite (0-20%), and a bone remodeling algorithm was used to evaluate the biomechanical characteristics of the ultimate bone configuration in the peri-implant tissue. RESULTS: The findings of the FEA reveal that osseointegration improves with changes in the density and mechanical properties of the bone surrounding Ti-HAP implants, which are influenced by the varying VF of hydroxyapatite in the FGM. SIGNIFICANCE: Increasing the hydroxyapatite fraction improves osseointegration, and appropriate length and diameter selection of Ti-HAP dental implants contribute to their stability and longevity.


Asunto(s)
Remodelación Ósea , Implantes Dentales , Durapatita , Análisis de Elementos Finitos , Oseointegración , Titanio , Remodelación Ósea/fisiología , Durapatita/química , Titanio/química , Mandíbula , Tomografía Computarizada por Rayos X , Humanos , Fenómenos Biomecánicos , Diseño de Prótesis Dental , Algoritmos , Ensayo de Materiales
5.
Sci Rep ; 12(1): 13848, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35974058

RESUMEN

In recent decades, aqueous two phase systems have gained a lot of attention for extraction of different materials. In this work, an aqueous two phase system was made by polyethylene glycol 600 and potassium hydroxide and phase diagram were determined for this system. The experimental binodal data were described using two empirical nonlinear three parameter expressions developed by Merchuk and Zafarani-Moattar. The consistency of the experimental tie-line data was determined by utilizing the Othmer-Tobias, Bancraft, and Setschenow correlations. Also, the extraction of two analgesic drugs, namely ibuprofen and acetaminophen were investigated by the mentioned ATPS. For this purpose, partition coefficients and extraction efficiencies of each drug were calculated. The trend of extraction efficiencies indicated that the responsibility of extraction of the mentioned drugs into the polymer-rich top phase is related to their hydrophobicity. The Diamond-Hsu equation and its modified version were used to correlate the drugs experimental partition coefficients. Furthermore, the interaction of mentioned drugs with polyethylene glycol was investigated employing quantum computing techniques based upon density functional theory (DFT). These results were in good agreement with the trend of extraction efficiencies of studied drugs.


Asunto(s)
Metodologías Computacionales , Polímeros , Analgésicos , Extracción Líquido-Líquido/métodos , Polietilenglicoles , Teoría Cuántica , Cloruro de Sodio , Agua
6.
J Pak Med Assoc ; 61(7): 622-4, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22204231

RESUMEN

OBJECTIVE: Cochlear implantation (CI) is an effective treatment for profound deaf patients. To study the cochlear implant complications in patients at Amir Aalam Hospital. METHODS: The study population involved 177 profoundly deaf patients, implanted within the same cochlear implant center. RESULTS: Twenty-four (13.6%) patients experienced complications. Early complications accrued in 9 (37.7%) patients within the first 24 hours. Eight (4.5%) patients had major complications including facial nerve paralysis, suture rupture and prosthesis rejection. Prosthesis rejection 6 (30%) was the most frequent major complication. Minor complications were found in 16 (9%) cases which were managed medically. Older age with CI was correlated with higher major complications. CONCLUSION: In contrast to minor complications, the frequency of major complications in this cohort was higher than that published by other groups.


Asunto(s)
Implantación Coclear/efectos adversos , Implantes Cocleares/estadística & datos numéricos , Sordera/cirugía , Complicaciones Posoperatorias/epidemiología , Adolescente , Adulto , Distribución por Edad , Niño , Preescolar , Sordera/diagnóstico , Sordera/epidemiología , Parálisis Facial/etiología , Femenino , Humanos , Lactante , Irán/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
7.
Eur J Pharm Sci ; 167: 106022, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34592461

RESUMEN

The effect of some deep eutectic solvents (DESs) on the coumarin solubility has been investigated using Hansen solubility parameters (HSP). The solubility of coumarin was measured in aqueous systems containing some DESs based on choline chloride (ChCl) as hydrogen bond acceptor (HBA) with urea (U), ethylene glycol (EG), and glycerol (GLY) as hydrogen bond donors (HBD) by widely applied shake-flask method at T = (298.15 to 313.15) K. The results indicate that coumarin solubility enhances with the concentration of DESs and temperature. Also, coumarin was dissolved more than 80 times compared with pure water in the presence of ChCl/EG. Then experimental data were fitted to Wilson, electrolyte Non-Random Tow-Liquid (e-NRTL), and UNIQUAC activity coefficient models. Furthermore, the dissolution thermodynamic properties including enthalpy, Gibbs free energy, and entropy have been calculated based on Gibbs and van't Hoff equations. Due to these results, it is indicated that coumarin dissolution in the studied systems is an endothermic process. Moreover, to investigate the biological properties of DESs, MTT assay have been applied to determinate cytotoxicity of the DESs. In the melanoma skin cell line, cell culture tests revealed that these solvents had very low toxicity and high biocompatibility.


Asunto(s)
Colina , Preparaciones Farmacéuticas , Cumarinas/toxicidad , Solubilidad , Solventes
8.
Adv Sci (Weinh) ; 8(16): e2004383, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34085417

RESUMEN

Wing-to-wing coupling mechanisms synchronize motions of insect wings and minimize their aerodynamic interference. Albeit they share the same function, their morphological traits appreciably vary across groups. Here the structure-material-function relationship of wing couplings of nine castes and species of Hymenoptera is investigated. It is shown that the springiness, robustness, and asymmetric behavior augment the functionality of the coupling by reducing stress concentrations and minimizing the impacts of excessive flight forces. A quantitative link is established between morphological variants of the coupling mechanisms and forces to which they are subjected. Inspired by the coupling mechanisms, a rotating-sliding mechanical joint that withstands tension and compression and can also be locked/unlocked is fabricated. This is the first biomimetic research of this type that integrates approaches from biology and engineering.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Biomimética/métodos , Modelos Biológicos , Alas de Animales/anatomía & histología , Alas de Animales/fisiología , Animales , Abejas , Avispas
9.
Acta Biomater ; 110: 188-195, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32360529

RESUMEN

Insects thrived soon after they acquired the ability to fly. Beyond the reach of the non-flying competitors, flying insects colonized a wide variety of habitats. Although flight is an efficient way to disperse and escape predators, it is energetically costly. Hence, various strategies are served to enhance flight efficiency as much as possible. A striking example is the development of wing-to-wing coupling mechanisms in many neopterous insects to minimize the aerodynamic interference of fore and hind wings. However, it remains unclear how the seemingly delicate coupling mechanisms can withstand excessive mechanical stresses encountered during flight. Here we studied the complicated coupling mechanism of drone honey bees, which consists of a set of tiny hooks and a thickened membrane. We found that the durability of the coupling mechanism results from two complementary strategies. First, the angles at which hooks and membrane are coupled and uncoupled may be adjusted, so that the resulting stresses are minimized. Second, the out-of-plane structure, soft base and pronounced tip reduce the stress developed in the hooks, yet maintaining the coupling strength. We anticipate our study, which presents the first numerical model of insect wing coupling mechanisms, to be a starting point for the development of more sophisticated models in the future. Such models are particularly useful for comparative analysis of the influence of different morphological features on the functionality of complex coupling mechanisms. STATEMENT OF SIGNIFICANCE: Hamuli, or 'tiny hooks', is the Greek term for hook-like structures on the anterior margin of honey bee hind wings. By fitting into the fold posterior margin of fore wings, the hooks couple the two wings to each other. Despite their seemingly fragile structure, the hooks withstand substantial mechanical stresses. We show that the out-of-plane structure, soft base and pronounced tip are morphological features that enhance the durability of the hooks, without compromising their function.


Asunto(s)
Vuelo Animal , Alas de Animales , Animales , Fenómenos Biomecánicos , Insectos , Modelos Biológicos , Estrés Mecánico
10.
Arch Iran Med ; 11(2): 196-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18298298

RESUMEN

In this study, we reviewed the surgical findings in a series of revision tympanomastoidectomy to determine the most common causes of failure in chronic otitis media surgery. The intraoperative findings at revision mastoidectomy with tympanoplasty of 116 patients were analyzed. The most common sites of pathologic tissue at revision surgery (with cholesteatoma and/ or granulation tissue) were unexenterated cells of the sinodural angle. The most common mechanical cause of retention of debris in canal wall down procedures was facial ridge.


Asunto(s)
Complicaciones Intraoperatorias/epidemiología , Otitis Media/cirugía , Adolescente , Adulto , Anciano , Niño , Enfermedad Crónica , Estudios Transversales , Femenino , Humanos , Irán/epidemiología , Masculino , Persona de Mediana Edad , Reoperación , Insuficiencia del Tratamiento
11.
Pathol Res Pract ; 208(2): 100-3, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22293278

RESUMEN

Survivin expression is correlated with suppression of apoptosis in human solid tumors. A polymorphism at position -31 (G/C) (rs 9904341) has been associated with cancer risk in several studies. We evaluated the correlation of this polymorphism with the risk of papillary thyroid carcinoma (PTC) in an Irananian population. The cases consisted of patients with PTC (n=123) and normal controls, composed of non-related healthy people (n=131). The frequency of GC or CC genotype in patients with PTC was significantly higher than in the controls [GC+CC vs GG, p=0.02 OR; 1.7, 95%CI (1.05-3.04)]. There was a significant difference between patients with more aggressive clinical manifestations, including lymphatic involvement compared to the controls [GC+CC vs GG, p=0.0006, OR; 3.7, 95%CI (1.6-9.2)]. The presence of C allele was significantly associated with the presence of more profound manifestations, including lymph node involvement, vascular involvement and multifocality.


Asunto(s)
Proteínas Inhibidoras de la Apoptosis/genética , Polimorfismo Genético , Neoplasias de la Tiroides/genética , Adulto , Carcinoma , Carcinoma Papilar , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Irán , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Fenotipo , Medición de Riesgo , Factores de Riesgo , Survivin , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/patología
12.
Iran J Allergy Asthma Immunol ; 10(2): 119-22, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21625020

RESUMEN

Both genetic and environmental factors seem to play role in the etiology of Meniere's disease (MD). Several genes may be involved in susceptibility of MD including Human Leukocyte Antigens (HLA). The associations between MD and HLA alleles have been previously studied in other populations and certain HLA alleles were shown to be predisposing. The aim of this study was to determine the association between HLA-C allele frequencies and definite MD in patients who refer to Amir-Alam otolaryngology tertiary referral center in Tehran. Patients with definite MD (N=22) enrolled according to the diagnostic criteria of American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS). Cases with all 3 symptoms of MD (Vertigo, Tinnitus and lower frequency of sensory-neural hearing loss) were included and those with suspected MD were excluded from study. HLA-Cw allele frequencies were determined in patients non-related healthy controls (N=91) using PCR -SSP. We found that the frequency of HLACw*04 was significantly higher in patients compared to the controls [P = 0.0015, OR; 20, 95% CI (3.7-196.9)]. Our results revealed that HLA-C is a genetic predisposing factor in definite MD in patients who refer to Amir-Alam otolaryngology tertiary referral center.


Asunto(s)
Alelos , Antígenos HLA-C/genética , Enfermedad de Meniere/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Frecuencia de los Genes , Humanos , Lactante , Masculino , Enfermedad de Meniere/etiología , Enfermedad de Meniere/inmunología , Persona de Mediana Edad
13.
Pathol Res Pract ; 207(7): 448-51, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21632186

RESUMEN

The aim of this article was to evaluate the expression of E-cadherin and CD44 adhesion molecule in oral tongue squamous cell carcinoma (SCC) since inappropriate expression of adhesion molecules raises the metastatic ability of the tumor cells. Biopsy specimens from 92 patients with tongue SCC were examined for the expression of E-cadherin and CD44 by immunohistochemistry. The relationship of immunoreactivity with tumor stage and cervical lymph node metastasis was then analyzed. Sixty-one patients (66.3%) had reduced or negative staining for CD44. Weak or absent staining for E-cadherin was seen in 14 patients (15.21%). Cervical lymph node metastasis is associated with decreased or negative staining for CD44, but no association was found between E-cadherin immunoreactivity and nodal metastasis. Our study reveals that reduced expression of CD44 could be an indicator of high invasiveness of tumor by increasing cervical lymph node metastasis.


Asunto(s)
Cadherinas/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Receptores de Hialuranos/metabolismo , Ganglios Linfáticos/patología , Neoplasias de la Boca/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/secundario , Femenino , Humanos , Ganglios Linfáticos/metabolismo , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/metabolismo , Cuello , Invasividad Neoplásica , Valor Predictivo de las Pruebas , Adulto Joven
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