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1.
Am J Orthod Dentofacial Orthop ; 165(2): 205-219, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37831020

RESUMO

INTRODUCTION: The objective of this study was to compare the skeletal and dental changes of patients with a Class II relationship treated with clear aligner mandibular advancement (MA) and Herbst appliances followed by comprehensive orthodontic treatment. METHODS: The participants included 20 patients treated with MA and 20 with the Herbst appliance. Orthodontic records were taken before treatment, after the functional appliance, and completion of phase II treatment. The skeletal and dental changes across the 3-time periods were evaluated using a matched paired t test for each treatment. A 2-sample t test was used to examine the changes across periods between 2 treatment groups (P <0.05). RESULTS: Significant reduction in overjet, overbite, and change in molar relationship were obtained by both appliances with similar skeletal and dental contributions. This was contributed by a forward movement of the mandible and mandibular molars, backward movement of the maxillary molars, and retraction of the maxillary incisors. After phase II treatment, both appliances could maintain the skeletal and dental changes achieved during the advancement phase. Greater change in overbite (2.4 mm vs 1.4 mm), an eruption of maxillary incisors (0.9 mm vs 0.1 mm), and proclination of mandibular incisors were found with the Herbst group (3.9° vs -2.1°). The average total treatment time was similar with the 2 appliances. CONCLUSIONS: Both functional appliances were equally effective in reducing the overjet and overbite and achieving a Class I molar relationship with a similar length of treatment time. The Herbst design lacked control of the mandibular incisor proclination, and clear aligners offered better vertical control and management of the mandibular incisor inclination.


Assuntos
Má Oclusão Classe II de Angle , Avanço Mandibular , Aparelhos Ortodônticos Funcionais , Aparelhos Ortodônticos Removíveis , Sobremordida , Humanos , Sobremordida/terapia , Cefalometria , Resultado do Tratamento , Má Oclusão Classe II de Angle/terapia , Mandíbula
2.
Ceram Int ; 47(3): 2917-2948, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32994658

RESUMO

Nanomedicine has seen a significant rise in the development of new research tools and clinically functional devices. In this regard, significant advances and new commercial applications are expected in the pharmaceutical and orthopedic industries. For advanced orthopedic implant technologies, appropriate nanoscale surface modifications are highly effective strategies and are widely studied in the literature for improving implant performance. It is well-established that implants with nanotubular surfaces show a drastic improvement in new bone creation and gene expression compared to implants without nanotopography. Nevertheless, the scientific and clinical understanding of mixed oxide nanotubes (MONs) and their potential applications, especially in biomedical applications are still in the early stages of development. This review aims to establish a credible platform for the current and future roles of MONs in nanomedicine, particularly in advanced orthopedic implants. We first introduce the concept of MONs and then discuss the preparation strategies. This is followed by a review of the recent advancement of MONs in biomedical applications, including mineralization abilities, biocompatibility, antibacterial activity, cell culture, and animal testing, as well as clinical possibilities. To conclude, we propose that the combination of nanotubular surface modification with incorporating sensor allows clinicians to precisely record patient data as a critical contributor to evidence-based medicine.

3.
Int J Hyperthermia ; 36(1): 104-114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30428737

RESUMO

PURPOSE: Although magnetite nanoparticles (MNPs) are promising agents for hyperthermia therapy, insufficient drug encapsulation efficacies inhibit their application as nanocarriers in the targeted drug delivery systems. In this study, porous magnetite nanoparticles (PMNPs) were synthesized and coated with a thermosensitive polymeric shell to obtain a synergistic effect of hyperthermia and chemotherapy. MATERIALS AND METHODS: PMNPs were produced using cetyltrimethyl ammonium bromide template and then coated by a polyethylene glycol layer with molecular weight of 1500 Da (PEG1500) and phase transition temperature of 48 ± 2 °C to endow a thermosensitive behavior. The profile of drug release from the nanostructure was studied at various hyperthermia conditions generated by waterbath, magnetic resonance-guided focused ultrasound (MRgFUS), and alternating magnetic field (AMF). The in vitro cytotoxicity and hyperthermia efficacy of the doxorubicin-loaded nanoparticles (DOX-PEG1500-PMNPs) were assessed using human lung adenocarcinoma (A549) cells. RESULTS: Heat treatment of DOX-PEG1500-PMNPs containing 235 ± 26 mg·g-1 DOX at 48 °C by waterbath, MRgFUS, and AMF, respectively led to 71 ± 4%, 48 ± 3%, and 74 ± 5% drug release. Hyperthermia treatment of the A549 cells using DOX-PEG1500-PMNPs led to 77% decrease in the cell viability due to the synergistic effects of magnetic hyperthermia and chemotherapy. CONCLUSION: The large pores generated in the PMNPs structure could provide a sufficient space for encapsulation of the chemotherapeutics as well as fast drug encapsulation and release kinetics, which together with thermosensitive characteristics of the PEG1500 shell, make DOX-PEG1500-PMNPs promising adjuvants to the magnetic hyperthermia modality.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Polietilenoglicóis/química , Humanos , Campos Magnéticos
4.
Biochim Biophys Acta ; 1840(1): 428-33, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24112973

RESUMO

BACKGROUND: For decades, contrast agents have been used to reduce longitudinal (T1) or transverse (T2) relaxation times. High toxicity of gadolinium-based contrast agents leads researchers to new T1 contrast agents. Manganese oxide (MnO) nanoparticle (NP) with the lower peril and good enough signal change ability has been offered as a new possibility for magnetic resonance imaging (MRI). METHODS: The synthesized NPs were investigated for physicochemical and biological properties by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscope, dynamic light scattering (DLS), inductively coupled plasma, enzyme-linked immunosorbent assay, and 3T magnetic resonance imaging. RESULTS: Due to physical contact importance of T1 contrast agents with tissues' protons, extremely thin layer of the surfactant, less than 2nm, was coated on NPs for aqueous stabilizing. The hydrophilic gentisic acid with low Dalton, around 154, did that role truly. Moreover, decreasing NP size to 5nm which increases available surface for the proton relaxation is another important parameter to reach an appropriate longitudinal relaxation rate. The NPs didn't reveal any side effects on the cells, and cellular uptake was considerable. CONCLUSIONS: The synthesized NPs represented a promising result in comparison to clinical gadolinium chelates, due to higher r1 relaxivity and lower toxicity. GENERAL SIGNIFICANCE: In addition to considerable signal change and cellular uptake, Prussian blue was tried on MnO NPs for the initial time, which can be observed within cells by pale blue color.


Assuntos
Apoptose , Proliferação de Células , Gentisatos/química , Compostos de Manganês/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Óxidos/química , Ensaio de Imunoadsorção Enzimática , Células HeLa , Humanos , Imageamento por Ressonância Magnética , Tamanho da Partícula , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
5.
Med J Islam Repub Iran ; 29: 190, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26034743

RESUMO

BACKGROUND: Ergonomic training had been implemented for prevention or reduction of neck and shoulder complaints among workers. The purpose of the present study was to assess the role of ergonomic training intervention on decreasing the prevalence of neck and shoulder complaints among workers of an automobile factory. METHODS: Within the present randomized clinical trial, the role of three ergonomic training methods on the prevalence of neck and shoulders pain among 503 workers of an automobile factory (Response rate: 94.23%) was assessed. The eligible workers were randomly allocated into the following three interventional (pamphlet, lecture, workshop) groups and one control group. The Nordic questionnaire was used to assess the prevalence of neck and shoulder complaints. We followed and assessed the prevalence of neck and shoulders complaints among the study employees before and one year after the intervention. We used chi-square and Mann-Whitney tests to compare the prevalence of neck and shoulder complaints between the trial and control groups. A two-tailed P-value less than or equal to 0.05 was considered statistically significant. RESULTS: The prevalence of neck and shoulders complaints among the study employees at the recent week (p= 0.002) and year (p= 0.02) had been significantly decreased in the study employees after participating in the study workshop. The prevalence of neck and shoulders complaints at the recent week and year did not significantly changed in the study employees after receiving the pamphlet and lecture as ergonomic trainings. CONCLUSION: Workshop as an ergonomic training method had an effective and powerful role on decreasing the prevalence of neck and shoulders complaints among workers.

6.
ACS Appl Mater Interfaces ; 16(3): 3019-3030, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38217858

RESUMO

Urease-powered nano/micromotors can move at physiological urea concentrations, making them useful for biomedical applications, such as treating bladder cancer. However, their movement in biological environments is still challenging. Herein, Janus micromotors based on black TiO2 with urease asymmetric catalytic coating were designed to take benefit of the optical properties of black TiO2 under near-infrared light and the movement capability in simulated bladder environments (urea). The black TiO2 microspheres were half-coated with a thin layer of Au, and l-Cysteine was utilized to attach the urease enzyme to the Au surface using its thiol group. Biocatalytic hydrolysis of urea through urease at biologically relevant concentrations provided the driving force for micromotors. A variety of parameters, such as urea fuel concentration, viscosity, and ionic character of the environment, were used to investigate how micromotors moved in different concentrations of urea in water, PBS, NaCl, and urine. The results indicate that micromotors are propelled through ionic self-diffusiophoresis caused by urea enzymatic catalysis. Due to their low toxicity and in vitro anticancer effect, micromotors are effective agents for photothermal therapy, which can help kill bladder cancer cells. These promising results suggest that biocompatible micromotors hold great potential for improving cancer treatment and facilitating diagnosis.


Assuntos
Urease , Neoplasias da Bexiga Urinária , Humanos , Terapia Fototérmica , Microesferas , Neoplasias da Bexiga Urinária/tratamento farmacológico , Ureia
7.
ACS Omega ; 8(44): 41363-41373, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37970037

RESUMO

This article presents a comprehensive study of the development of a novel nanocomposite comprising core-shell Fe3O4@MCM-41 with superparamagnetic properties and hydroxyapatite (HAp). The nanocomposite serves as a pH-responsive nanocarrier, offering an efficient injectable dosage for teriparatide (PTH (1-34)) delivery. The aim is to address the limitations associated with drug-induced side effects, precautionary measures, and frequent injections. The nanocomposites, as prepared, were characterized using techniques including X-ray diffraction, Fourier transform infrared, zeta potential, dynamic light scattering, VSM, scanning electron microscopy, and transmission electron microscopy. The nanocomposites' average crystallite diameter was determined to be 27 ± 5 nm. The hydrodynamic size of the PTH (1-34)-loaded nanocarrier ranged from 357 to 495 nm, with a surface charge of -33 mV. The entrapment and loading efficiencies were determined to be 73% and 31%, respectively. All of these findings collectively affirm successful fabrication. Additionally, in vivo medication delivery was investigated using the HPLC method, mirroring the in vitro tests. Utilizing the dialysis approach, we demonstrated sustained-release behavior. PTH (1-34) diffusion increased as the pH decreased from 7.4 to 5.6. After 24 h, drug release was higher at acidic pH (88%) compared to normal pH (43%). The biocompatibility of the PTH (1-34)-loaded nanocarrier was assessed using the MTT assay employing the NIH3T3 and HEK-293 cell lines. The results demonstrated that the nanocarrier not only exhibited nontoxicity but also promoted cell proliferation and differentiation. In the in vivo test, the drug concentration reached 505 µg within 30 min of exposure to the magnetic field. Based on these findings, the Fe3O4@MCM-41/HAp/PTH (1-34) nanocomposite, in combination with a magnetic field, offers an efficient and biocompatible approach to enhance the therapeutic effect of osteogenesis and overcome drug limitations.

8.
Anal Chim Acta ; 1220: 340030, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35868699

RESUMO

A recyclable optical nanosensor was developed by immobilizing l-tyrosine functionalized silver nanoparticles (AgNPs) on the polyethylene terephthalate (PET) substrate for rapid determination of Pb2+ ions. At first, the l-tyrosine functionalized AgNPs were assessed in the solution phase; the response time was lower than 15 s, and a limit of detection lower than 9 nM was obtained in the dynamic range of 1-1000 nM. For fabrication of the optical assay kit, the design of experiment (DOE) was used to optimize the immobilization efficiency of the nanoparticles on PET films by studying AgNO3 concentration and pH as two crucial parameters. The assay kit in optimal conditions showed a sharp localized surface plasmon resonance band suitable for sensitive determination of Pb2+. The fabricated sensor showed promising results for rapid determination of lead ions with the limit of detection value as low as 1 nM (S/N = 3). The sensor reproduced the obtained results even after three consecutive runs, which proved the recyclability of the optical assay kit. The recoveries of the spiked concentration in real samples were in the range of 95%-103%, which confirmed the applicability of the sensor in practical applications.


Assuntos
Nanopartículas Metálicas , Prata , Íons , Chumbo , Ressonância de Plasmônio de Superfície/métodos , Tirosina
9.
Iran Endod J ; 17(4): 195-199, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36703688

RESUMO

Introduction: Electronic apex locators are among the most acceptable instruments for determining root canal length. The present study aimed to evaluate the effect of long service life on the accuracy of the Dentaport Root ZX (DP ZX) electronic apex locator (EAL). Materials and Methods: In this study, fifty single-rooted freshly extracted human teeth were used. After determining the root canal length with a K-file and a dental operative microscope, the canals were measured with four separate DP ZX apex locators (two with more than 6 years of life service while two others had less than 6 years of life service). Data were analyzed by repeated ANOVA measurement. Results: No significant difference was found between the EALs with different years of life services (P=0.62). All EALs could determine root canal length with high accuracy of more than 94%. Conclusion: Based on the results of this in vitro study, the long service life had no significant impact on the accuracy of DP ZX EALs in terms of root canal length determination.

10.
Appl Nanosci ; 11(3): 849-860, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33425639

RESUMO

In this research, a facile, two-step synthesis of Fe3O4-LCysteine-graphene quantum dots (GQDs) nanocomposite is reported. This synthesis method comprises the preparation of GQDs via hydrothermal route, which should be conjugated to the LCysteine functionalized core-shell magnetic structure with the core of about 7.5-nm iron oxide nanoparticle and 3.5-nm LCysteine shell. LCysteine, as a biocompatible natural amino acid, was used to link magnetite nanoparticles (MNPs) with GQDs. X-ray powder diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray were used to investigate the presence and formation of MNPs, L Cysteine functionalized MNPs, and final hybrid nanostructure. Morphology and size distribution of nanoparticles were demonstrated by scanning electron microscopy and transmission electron microscopy. Finally, the magnetic and optical properties of the prepared nanocomposite were measured by vibrating sample magnetometer, ultraviolet-visible, and photoluminescence spectroscopy. The results show that Fe3O4-LCysteine-GQDs nanocomposite exhibits a superparamagnetic behavior at room temperature with high saturation magnetization and low magnetic coercivity, which are 28.99 emu/g and 0.09 Oe, respectively. This nanocomposite also shows strong and stable emission at 460 nm and 530 nm when it is excited with the 235 nm wavelength. The magnetic GQDs structure also reveals the absorption wavelength at 270 nm. Therefore, Fe3O4-LCysteine-GQDs nanocomposite can be considered as a potential multifunctional hybrid structure with magnetic and optical properties simultaneously. This nanocomposite can be used for a wide range of biomedical applications like magnetic resonance imaging (MRI) contrast agents, biosensors, photothermal therapy, and hyperthermia.

11.
Bioimpacts ; 11(1): 45-52, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33469507

RESUMO

Introduction: Porous 3D scaffolds synthesized using biocompatible and biodegradable materials could provide suitable microenvironment and mechanical support for optimal cell growth and function. The effect of the scaffold porosity on the mechanical properties, as well as the TiO2 nanoparticles addition on the bioactivity, antimicrobial, photocatalytic, and cytotoxicity properties of scaffolds were investigated. Methods: In the present study, porous scaffolds consisting poly (lactide-co-glycolide) (PLGA) containing TiO2 nanoparticles were fabricated via air-liquid foaming technique, which is a novel method and has more advantages due to not using additives for nucleation compared to former ways. Results: Adjustment of the foaming process parameters was demonstrated to allow for textural control of the resulting scaffolds and their pore size tuning in the range of 200-600 µm. Mechanical properties of the scaffolds, in particular, their compressive strength, revealed an inverse relationship with the pore size, and varied in the range of 0.97-0.75 MPa. The scaffold with the pore size 270 µm, compressive strength 0.97 MPa, and porosity level 90%, was chosen as the optimum case for the bone tissue engineering (BTE) application. Furthermore, 99% antibacterial effect of the PLGA/10 wt.% TiO2 nanocomposite scaffolds against the strain was achieved using Escherichia coli. Besides, no negative effect of the new method was observed on the bioactivity behavior and apatite forming ability of scaffolds in the simulated body fluid (SBF). This nanocomposite also displayed a good cytocompatibility when assayed with MG 63 cells. Lastly, the nanocomposite scaffolds revealed the capability to degrade methylene blue (MB) dye by nearly 90% under the UV irradiation for 3 hours. Conclusion: Based on the results, nanocomposite new scaffolds are proposed as a promising candidate for the BTE applications as a replacement for the previous ones.

12.
Mol Biotechnol ; 61(7): 528-540, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31065900

RESUMO

Tall fescue plants are widely exposed to white grubs. Regarding the rate of damage caused by the white grubs to tall fescue and difficulty of its ecological and economical control, production of resistant cultivars is a priority. In this experiment, for the first time, we report production of transgenic lines resistant to white grub using CR8DB gene. For this, mature seeds were placed on MS basal medium with 0-15 mg L-1 2,4-D for callogenesis and 0-1.75 mg L-1 BA for regeneration. 'Asterix' (54.11%) in 7.5 and 'Talladega' (52.53%) in 10 mg L-1 2,4-D showed maximum callogenesis. Regeneration percentage was higher in 0.5 mg L-1 BA. Agrobacterium tumefaciens strain LBA4404 harbouring binary vector pCAMBIA 1301 with CRY8DB gene, which contains HPTII gene and uidA and various types MS media were used for transformation of calli. The highest percentage of gus enzyme activity and hygromycin resistance in calli was related to the modified medium type 11. The PCR and RT-PCR analysis was done to confirm the presence and expression of the target gene in transgenic 5 lines in 'Asterix' and 3 lines in 'Talladega'. According to bioassay, larvae mortality of 91.66% was observed in transgenic plants, whereas it was 15.52% in control plants.


Assuntos
Agrobacterium tumefaciens/genética , Toxinas Bacterianas/genética , Besouros , Festuca/genética , Plantas Geneticamente Modificadas/genética , Agrobacterium tumefaciens/metabolismo , Animais , Toxinas Bacterianas/biossíntese , Besouros/microbiologia , Festuca/microbiologia , Proteínas de Insetos/metabolismo , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/microbiologia , Receptores de Superfície Celular/metabolismo , Técnicas de Cultura de Tecidos , Transformação Genética
13.
Mater Sci Eng C Mater Biol Appl ; 82: 265-276, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29025657

RESUMO

It is known that Fluoride ions strongly affect bone mineralization and formation. In the present study, the engineered bone tissue scaffolds are fabricated using silk fibroin (SF) and flouridated TiO2 nanoparticles. TiO2 nanoparticles are modified by fluoride ions, and different levels (0, 5, 10, 15 and 20wt%) of the fluoridated TiO2 nanoparticles (TiO2-F) were subsequently added to the SF matrix through phase separation method to prepare silk fibroin/flouridated TiO2 nanocomposite scaffolds (SF/TiO2-F). Phase structure, functional groups, morphology and mechanical properties of the obtained scaffolds were evaluated by X-ray diffraction method (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and compressive testing, respectively. In vitro degradation studies of scaffolds were performed by incubating the samples in phosphate buffered saline (PBS) at 37°C and pH7.4 for 30days. Additionally, the bioactivity of scaffolds was estimated in a simulated body fluid (SBF) buffered at 37°C and pH7.4 for 28days. Moreover, MTT assay was used to confirm the biocompatibility of the scaffolds using human like SaOS-2 osteoblast cell line for 1, 3 and 5days. The obtained results indicated that the mechanical properties of scaffolds have been improved by increasing the TiO2-F amount up to 15wt%. However, a detrimental effect was observed by a further increase in the TiO2-F content. The bioactivity of SF/TiO2-F nanocomposite scaffolds was promoted by flouridation of TiO2. Furthermore, cell cytotoxicity results demonstrated that the SF/TiO2-F nanocomposite scaffolds are nontoxic to osteoblasts. The cell fixation results after 3days of incubation revealed that the cell attachment and spreading on SF/TiO2-F nanocomposite scaffolds are improved with respect to SF/TiO2 nanocomposite scaffolds control sample.


Assuntos
Materiais Biocompatíveis/química , Fibroínas/química , Nanocompostos/química , Titânio/química , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Halogenação , Humanos , Microscopia Eletrônica de Varredura , Porosidade , Seda/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
PLoS One ; 12(7): e0181768, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28742129

RESUMO

BACKGROUND: Non-syndromic clefts lip and/or palate (CL/P) defects may have manifold significant and detrimental consequences for the affected individuals and their family environment. Although the use of pre-surgical infant orthopedics (PSIO) was introduced as a means to improve management and treatment outcomes, there still remains a controversy. OBJECTIVE: To investigate the effectiveness of PSIO in patients with non-syndromic CL/P and evaluate the quality of the available evidence. SEARCH METHODS: Search without restrictions, together with hand searching, until May 2016. SELECTION CRITERIA: Randomized clinical trials investigating the effects of pre-surgical infant orthopedic appliances. DATA COLLECTION AND ANALYSIS: Following study retrieval and selection, data extraction and individual study risk of bias assessment using the Cochrane Risk of Bias Tool took place. The overall quality of the available evidence was assessed with the Grades of Recommendation, Assessment, Development and Evaluation approach. RESULTS: Finally 20 papers (3 unique trials) were identified, involving a total of 118 patients with unilateral complete CL/P and 16 with cleft of the soft and at least two thirds of the hard palate. Eight publications were considered as being of low, four of unclear and eight of high risk of bias. In general, the investigated appliances did not present significant effects when compared to each other or to no treatment in terms of feeding and general body growth, facial esthetics, cephalometric variables, maxillary dentoalveolar variables and dental arch relationships, speech and language evaluation, caregiver-reported outcomes, economic evaluation, as well as, adverse effects and problems. Overall, the quality of the available evidence was considered low. CONCLUSIONS: The aforementioned findings could provide initial guidance in the clinical setting. However, given the multitude of parameters, which may have affected the results, good practice would suggest further research, in order to reach more robust relevant recommendations for management decisions in individual cases.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Humanos , Lactente , Procedimentos Ortopédicos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
15.
Cell Mol Bioeng ; 10(3): 263-272, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31719864

RESUMO

The combination of liposomes with magnetic nanoparticles, because of their strong effect on T2 relaxation can open new ways in the innovative cancer therapy and diagnosis. In order to design an intelligent contrast agent in MRI, we chose anti-HER2 nanobody the smallest fully functional antigen-binding fragments evolved from the variable domain, the VHH, of a camel heavy chain-only antibody. These targeted magnetoliposomes bind to the HER2 antigen which is highly expressed on breast and ovarian cancer cells so reducing the side effects as well as increasing image contrast and effectiveness. Cellular iron uptake analysis and in vitro MRI of HER2 positive cells incubated with targeted nanoparticles show specific cell targeting. In vitro MRI shows even at the lowest density (200 Cells/µl), dark spots corresponding to labeled cells which were still detectable. These results suggest that this new type of nanoparticles could be effective antigen-targeted contrast agents for molecular imaging.

16.
J Tehran Heart Cent ; 12(2): 57-64, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28828020

RESUMO

Background: L-carnitine may prevent the incidence of AKI by its antioxidant effects and improving circulation in ischemic conditions. The goal of this trial was to evaluate the impact of L-carnitine on contrast-induced nephropathy in patients undergoing elective PCI. Methods: Totally, the patients were randomly allocated to 2 groups. The treatment group received 1 g of L-carnitine orally 3 times a day, 24 hours before the procedure (3 g before PCI) and 2 g after PCI, whereas the control group did not receive L-carnitine. In both groups, the plasma level of neutrophil gelatinase-associated lipocalin (NGAL) was measured at baseline and 12 hours after PCI. Results: Our study was conducted on 202 patients (including 91 vs. 111 patients in the treatment and the control group; 31 (34.1%) vs 33 (29.7%) female in carnitine and control group; and ages include 62.0 ± 9.0 vs 57.0 ± 11.2 years). The median plasma levels of NGAL were not different between the carnitine and control groups at baseline (57 [IQR: 22 - 255] vs. 54 [IQR: 29 - 324]; p value = 0.155) and 12 hours after PCI (71 [IQR: 52 - 129] vs. 70 [IQR: 46 - 153]; p value = 0.925), but the changes in the plasma NGAL from baseline to 12 hours after PCI were different between the 2 groups (5 [IQR:-147 - 30] vs. 17 [IQR: -21 - 41]; p value = 0.010). Conclusion: Our results showed that oral L-carnitine was able to prevent an increase in NGAL following contrast medium administration in patients undergoing PCI. More studies should be performed to fully elucidate the nephroprotective effects of L-carnitine.

17.
Iran J Pharm Res ; 16(1): 158-164, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496471

RESUMO

Celecoxib is classified as none traditional nonsteroidal anti-inflammatory drugs (NSAIDs). This compound has conventional properties of NSAIDs such as anti-inflammatory, analgesic, and antipyretic activities beside reduced risk of gastrointestinal side effect of traditional NSAIDs such as ibuprofen. This compound gets a second sale rank of NSAIDs market at 2016 in the world and sales more than 17000 Kg in Iran during the past 6 month. So, a simple, rapid and green method for synthesis of this compound is important. In the present study, a novel green method was suggested for the synthesis of celecoxib using the ionic liquid. Celecoxib was provided by the reaction of trifluoroacetone, 4-methylbenzoylchloride, and 4-hydrazinobenzenesulfonamide hydrochloride. The tris-(2-hydroxyethyl) ammonium acetate as ionic liquid was prepared by mixing tris-(2-hydroxyethyl) ammonium and acetic acid, and used as an efficient catalyst. The structure of the synthetic products was confirmed by analytical and spectroscopic methods including 1HNMR, 13CNMR, IR, MS and elemental analysis. This ionic liquid can play dual roles in the synthesis of celecoxib, as a catalyst to improve electrophilicity of carbonyl group and also as a solvent of reaction. The reaction rate and yield (86%) were improved considerably. Moreover IL showed the same efficiency when used in 4 consecutive reactions.

18.
Nanoscale ; 9(35): 12779-12820, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-28832057

RESUMO

Recently, a wide variety of research works have focused on carbon nanotube (CNT)-ceramic matrix nanocomposites. In many cases, these novel materials are produced through conventional powder metallurgy methods including hot pressing, conventional sintering, and hot isostatic pressing. However, spark plasma sintering (SPS) as a novel and efficient consolidation technique is exploited for the full densification of high-temperature ceramic systems. In these binary nanocomposites, CNTs are added to ceramic matrices to noticeably modify their inferior properties and SPS is employed to produce fully dense compacts. In this review, a broad overview of these systems is provided and the potential influences of CNTs on their functional and structural properties are addressed. The technical challenges are then mentioned and the ongoing debates over overcoming these drawbacks are fully highlighted. The structural classification used is material-oriented. It helps the readers to easily find the material systems of interest. The SPSed CNT-containing ceramic matrix nanocomposites are generally categorized into four main classes: CNT-oxide systems; CNT-nitride systems, CNT-carbide systems, and CNT-boride systems. A large number of original curves and bubble maps are provided to fully summarize the experimental results reported in the literature. They pave the way for obviously selecting the ceramic systems required for each industrial application. The properties in consideration include the relative density, hardness, yield strength, fracture toughness, electrical and thermal conductivities, modulus, and flexural strength. These unique graphs facilitate the comparison between reported results and help the reader to easily distinguish the best method for producing the ceramic systems of interest and the optimal conditions under which the superior properties can be reached. The authors have concentrated on the microstructure evolution-physicomechanical property relationship and tried to relate each property to pertinent microstructural phenomena and address why the properties are degraded or enhanced with the variation of SPS conditions or material parameters.

19.
Contrast Media Mol Imaging ; 11(5): 340-349, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27307214

RESUMO

The purpose of this work is evaluating the effect of ultra small superparamagnetic iron oxide nanoparticles (USPIONs) coatings on encapsulation efficiency in liposomes and cellular cytotoxicity assay. Moreover, we assessed the effects of surface engineering on the relaxivity of magnetoliposome nanoparticles in order to create a targeted reagent for the intelligent diagnosis of cancers by MRI. For estimating the effect of nanoparticle coatings on encapsulation, several kinds of USPIONs coated by dextran, PEG5000 and citrate were used. All kinds of samples are monodispersed and below 100 ± 10 nm and the coatings of USPIONs have no significant effect on magnetoliposome diameter. The coating of USPIONs could have effect on percentage of encapsulation. The dextran coated USPIONs have more stability and quality accordingly the encapsulation increased up to 92%, then the magnetoliposome nano particles have been targeted by Herceptin and anti-HER2 VHH, separately. Over storage period of four weeks the resulting particles were stable and physico-chemical properties such as size and zetapotential did not show any significant changes. The relaxivity of contrast agents was measured using a 1.5 T MRI. The r2/r1 ratio was more than two for all samples which demonstrate the negative contrast enhancing of all SPION embedded specimens. The high ratio of r2/r1 as well as high r2 is the best combination of a negative contrast agent as it is obtained for pure magnetite. The value of r2/r1 for all other samples including Herceptin targeted magnetoliposome, anti-HER2 VHH targeted magnetoliposome and non-targeted magnetoliposome were between ~21 to ~28, which show the magnetite embedded samples have enough negative contrast to be detectable by MRI. Therefore the HER2 targeted magnetoliposomes are a good and stable candidate as contrast agents in clinical radiology and biomedical research with minimal cytotoxicity and biocompatibility effects. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Lipossomos/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita , Neoplasias/diagnóstico por imagem , Ácido Cítrico , Materiais Revestidos Biocompatíveis/normas , Meios de Contraste , Dextranos , Óxido Ferroso-Férrico , Humanos , Nanopartículas de Magnetita/química , Polietilenoglicóis , Receptor ErbB-2/imunologia , Anticorpos de Domínio Único/imunologia
20.
Iran Endod J ; 11(2): 79-84, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27141212

RESUMO

INTRODUCTION: The aim of the present study was to compare the efficacy of 2% lidocaine to 4% articaine in buccal infiltration of maxillary first molars with irreversible pulpitis. Moreover, the effect of root length on success of anesthesia irrespective of the type of anesthetic agent was assessed. METHODS AND MATERIALS: Fifty patients suffering from painful maxillary first molars with irreversible pulpitis received an infiltration injection of either 4% articaine with 1:100000 epinephrine or 2% lidocaine with 1:80000 epinephrine. Each patient recorded their pain score in response to a cold test on a Heft-Parker visual analogue scale (VAS) before commencing the treatment, 5 min following injection, during access preparation, after pulp exposure and during root canal instrumentation. No or mild pain at any stage was considered a success. Data were analyzed using the multivariate logistic regression analysis, chi-square and t tests. RESULTS: Finally, 47 out of 50 patients were eligible to be included in this study. The anesthetic success rates in the lidocaine and articaine groups were 56.52% and 66.67%, respectively and the difference was not significant (P=0.474). Irrespective of the anesthetic agent, the length of the palatal root (Odds Ratio=0.24, P=0.007) had an adverse effect on anesthetic success. There was an association between longer palatal root length and anesthetic failure. CONCLUSION: No significant difference was found between 2% lidocaine and 4% articaine in terms of anesthetic success in maxillary first molars with irreversible pulpitis. The length of the palatal root had a significant negative influence on anesthetic success.

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