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Adult neurogenesis has been reported in the hypothalamus, subventricular zone and subgranular zone in the hippocamp. Recent studies indicated that new cells in the hypothalamus are affected by diet. We previously showed beneficial effects of safflower seed oil (SSO), a rich source of linoleic acid (LA; 74%), on proliferation and differentiation of neural stem cells (NSCs) in vitro. In this study, the effect of SSO on hypothalamic neurogenesis was investigated in vivo, in comparison to synthetic LA. Adult mice were treated with SSO (400 mg/kg) and pure synthetic LA (300 mg/kg), at similar concentrations of LA, for 8 weeks and then hypothalamic NSCs were cultured and subsequently used for Neurosphere-forming assay. In addition, serum levels of brain-derived neurotrophic factor (BNDF) were measured using enzyme-linked immunosorbent assay. Administration of SSO for 8 weeks in adult mice promoted the proliferation of NSCs isolated from SSO-treated mice.Immunofluorescence staining of the hypothalamus showed that the frequency of astrocytes (glial fibrillary acidic protein+ cells) are not affected by LA or SSO. However, the frequency of immature (doublecortin+ cells) and mature (neuronal nuclei+ cells) neurons significantly increased in LA- and SSO-treated mice, compared to vehicle. Furthermore, both LA and SSO caused a significant increase in the serum levels of BDNF. Importantly, SSO acted more potently than LA in all experiments.The presence of other fatty acids in SSO, such as oleic acid and palmitic acid, suggests that they could be responsible for SSO positive effect on hypothalamic proliferation and neurogenesis, compared to synthetic LA at similar concentrations.
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The aim of this study was to develop a novel multifunctional nanoparticle, which encapsulates SPION and Gemcitabine in PLGA +/- PEG to form multifunctional drug delivery system. For this aim, super paramagnetic iron oxide nanoparticles [SPIONs] were simultaneously synthesized and encapsulated with Gemcitabine [Gem] in PLGA +/- PEG copolymers via W/O/W double emulsification method. Optimum size and encapsulation efficiency for radiosensitization, hyperthermia and diagnostic applications were considered and the preparation parameters systematically were investigated and physicochemical characteristics of optimized nanoparticle were studied. Then SPION-PLGA and PLGA-Gem nanoparticles were prepared with the same optimized parameters and the toxicity of these nanoparticles was compared with Gemcitabine in human breast cancer cell line [MCF-7]. The optimum preparation parameters were obtained with Gem/polymer equal to 0.04, SPION/polymer equal to 0.8 and 1% sucrose per 20 mg of polymer. The hydrodynamic diameters of all nanoparticles were under 200 nm. Encapsulation efficiency was adjusted between 13.2% to 16.1% for Gemcitabine and 48.2% to 50.1% for SPION. In-vitro Gemcitabine release kinetics had controlled behavior. Enhancement ratios for PLGA-Gem and SPION-PLGA-Gem at concentration of nanoparticles equal to IC50 of Gemcitabine were 1.53 and 1.89 respectively. The statistical difference was significant [p-value = 0.006 for SPION-PLGA-Gem and p-value = 0.015 for PLGA-Gem compared with Gemcitabine]. In conclusion, we have successfully developed a Gemcitabine loaded super paramagnetic PLGA-Iron Oxide multifunctional drag delivery system. Future work includes in-vitro and in-vivo investigation of radiosensitization and other application of these nanoparticles
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Gene therapy as a modern therapeutic approach has not yet advanced to a globally-approved therapeutic approach. Lack of adequate reliable gene delivery system seems to be one of the major reasons from the pharmaceutical biotechnology point of view. Main obstacles delaying successful application of human gene therapy are presented in this review. The unique advantages of non-biological gene carriers as compared to their biological counterparts make them ideal alternatives for overcoming extra- and intracellular barriers in a more safely manner. We, therefore, highlight the significant contributions in non-biological gene delivery and favorable characteristics of different design attitudes with focus on in vivo approaches. Bypassing the rapid extracellular enzymatic degradation of genetic materials is covered in extracellular segment of this review with emphasis on PEGylated and targeted formulations. The successful approaches to pave the rest of the way from cellular uptake to intracellular transfer and gene expression of unpacked DNA are also discussed. From these approaches, we emphasize more on optimization of cationic-based polymers and dendrimers, developing newly designed membrane-effective components, and adjusting the hydrophilic-hydrophobic balance of the synthesized vectors
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Genes , Terapia Genética , DNA , Expressão Gênica , Polímeros , DendrímerosRESUMO
Statement of the Problem: Soldering is a process commonly used in fabricating dental prosthesis. Since most soldered prosthesis fail at the solder joints; the joint strength is of utmost importance
Purpose: The purpose of this study was to evaluate the effect of gap angle on the tensile strength of base metal solder joints
Materials and Method: A total number of 40 Ni-Cr samples were fabricated according to ADA/ISO 9693 specifications for tensile test. Samples were cut at the midpoint of the bar, and were placed at the considered angles by employing an explicitly designed device. They were divided into 4 groups regarding the gap angle; Group C [control group] with parallel gap on steady distance of 0.2mm, Group 1: 10[degree sign], Group 2: 20[degree sign], and Group3: 30[degree sign] gap angles. When soldered, the specimens were all tested for tensile strength using a universal testing machine at a cross-head speed of 0.5 mm/min with a preload of 10N. Kruskal-Wallis H test was used to compare tensile strength among the groups [p< 0.05]
Results: The mean tensile strength values obtained from the study groups were respectively 307.84, 391.50, 365.18, and 368.86 MPa. The tensile strength was not statistically different among the four groups in general [p= 0.490]
Conclusion: Making the gap angular at the solder joints and the subsequent unsteady increase of the gap distance would not change the tensile strength of the joint
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The prevalence of astigmatism, and the astigmatic axis, and their determinants were evaluated in a rural population of Iran. In a cross-sectional study conducted from May to August 2011, 13 villages in the vicinity of the city of Khaf in northeast Iran were investigated in this study. All the examinations including visual acuity, refraction, slit-lamp biomicroscopy and fundoscopy were performed in a Mobile Eye Clinic. Written informed consent was obtained from all participants. Only phakic eye that could be reliably refracted without a previous history of ocular surgery were included. Out of 2635 participants who were screened, 2124 were analysed for this study of whom 52% were female. The prevalence of astigmatism was 32.2% [95% confidence intervals [CI]: 30.2-34.2]. Astigmatism significantly increased from 14.3% in the under 15-year-old age group to 67.2% in the age group of over 65-years old [P < 0.001]. The prevalence of With-The-Rule [WTR], Against-The-Rule [ATR], and oblique astigmatism was 11.7%, 18.1%, and 2.4%, respectively. ATR significantly increased with age [P < 0.001]. The mean corneal astigmatism was 0.73 D which linearly increased with age [P < 0.001]. Attention must be paid to astigmatism in rural areas due to the high prevalence. Further studies are suggested to discover the role of the environmental and genetic factors. It seems that environmental and occupational factors in the villages cause a significant increase in the prevalence of astigmatism with age. A high percentage of participants had ATR astigmatism, which was more common at older ages.
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Humanos , Masculino , Feminino , Prevalência , População Rural , Estudos TransversaisRESUMO
Among synthetic carriers, dendrimers with the more flexible structure have attracted a great deal of researchers' attention in the field of gene delivery. Followed by the promising results upon hydrophobic modification on polymeric structures in our laboratory, alkylated poly [propylenimine]-based carriers were synthesized by nucleophilic substitution of amines with alkyl moieties and were further characterized for their physicochemical and biological characteristics for plasmid DNA delivery. Although not noticeably effective gene transfer activity for hexanoate- and hexadecanoate- modified series was observed, but alkylation by decanoic acid significantly improved the transfection efficiency of the final constructs up to 60 fold in comparison with unmodified poly[propylenimine] [PPI]. PPI modified by 10-bromodecanoic acid at 50% grafting, showed significantly higher gene expression at c/p ratio of 2 compared to Superfect as positive control. Overall, modification of PPI with 50% primary amines grafting with 10-bromodecanoic acid could increase the transfection efficiency which is occurred at lower c/p ratio when compared to Superfect, i.e. less amount of modified vector is required to exhibit the same efficiency as Superfect. Therefore, the obtained constructs seem to be safer carriers for long-term gene therapy applications
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Alquilação , Polipropilenos , Interações Hidrofóbicas e HidrofílicasRESUMO
This study investigates the production of crude Caindependent and low pH active alpha-amylase by Bacillus sp. KR-8104 in submerged fermentation [SmF] and solid-state fermentation [SSF] systems. Different parameters were evaluated in each system using "one factor at a time" approach to improve the production of enzyme. The results showed that in the SmF the maximum enzyme production was achieved in culture medium that contained dextrin as a carbon source, as well as yeast extract and meat extract as nitrogen sources incubated at 37§C and 180 rpm for 48 h. While SSF of Bacillus sp. KR-8104 using wheat bran [WB] as a substrate showed that using tap water or distilled water as a moisturizing agent, a substrate-water ratio of 1:1.5 [w/v] and incubation at 37§C for 48 h gave the maximum alpha-amylase production. From different extraction medium examined in this study 0.1% [v/v] aqueous mixture of Tween 20 and distilled water illustrated maximum results [100 U/g]
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Anti-Rh D IgG is used for the prevention of anti-D antibody production in Rh- individuals who have been exposed to Rh+ red blood cells. The stability of IgG preparations as a solution is low, with a shelf life of a year or more. Formulation of anti-Rh D IgG as a lyophilized preparation would decrease its degradation rate and increases its shelf life. The objective of this study was to formulate the anti-Rh D as a lyophilized preparation using different formulations and optimize the lyophilization processes. The effect of various formulations on the stability of anti-Rh D was evaluated using accelerated stability test. In this method the amount of transmittance [T%] at 585 nm for the lyophilized preparations had inverse relationship with aggregation of anti-Rh D. To improve stability, the most stable formulation was selected and different concentrations of sucrose in the presence of sodium-potassium phosphate buffer 25 mM pH 7.5. Then, the bioactivity was determined, using the ELAT test and also, the amount of moisture measured in this formulation. Among different formulations, the one with anti-Rh D 5 mg/ml, tween 80 0.1%, glycine 0.15 M, manitol 7% and sucrose 60 mM in sodium-potassium phosphate buffer 25 mM pH 7.5 was the most stable formulation [P < 0.05]. The result of biological test of ELAT showed that bioactivity of more than 93% meets the requirement set by British Pharmacopoeia. The amount of moisture measured in this formulation was less than 3%. It was concluded that this formulation could be introduced as a candidate for the formulation of anti-Rh D in a lyophilized dosage form
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Imunoglobulinas , Liofilização , Química Farmacêutica , Estabilidade de Medicamentos , Imunoglobulina G , Sacarose , Sódio , FosfatosRESUMO
Delivery of drugs into systemic circulation via skin has generated lots of interest during the last decade. Transdermal drug delivery systems offer many advantages over the conventional forms or sustained release delivery systems. When technically feasible, topical delivery of drug products for both local and systemic indications offer many advantages over oral or parenteral routes, such as the need for fewer administration, constant blood level, elimination of the potential for both under and overdosing, and avoidance of first-pass metabolism. Skin structure shows that it is relatively impermeable to exogenous substances and drugs. Understanding this structure will help us to improve drug delivery using prodrugs, chemical enhancers, iontophoresis, electroporation and ultrasound waves. This review will overview the structure and function of skin, the skin routes, the interactions between skin and drug delivery systems and advantageous and disadvantageous of skin as a route for drug delivery. Thus the properties and interactions of three entities-the skin, the drug and the drug delivery excipients-is going to be considered