18 research outputs found
Glaucoma, Stem Cells, and Gene Therapy: Where Are We Now?
Glaucoma is the second most common cause of blindness, affecting 70∼80 million people around the world. The death of retinal ganglion cells (RGCs) is the main cause of blindness related to this disease. Current therapies do not provide enough protection and regeneration of RGCs. A novel opportunity for treatment of glaucoma is application of technologies related to stem cell and gene therapy. In this perspective we will thus focus on emerging approaches to glaucoma treatment including stem cells and gene therapy
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Glaucoma, Stem Cells, and Gene Therapy: Where Are We Now?
Glaucoma is the second most common cause of blindness, affecting 70∼80 million people around the world. The death of retinal ganglion cells (RGCs) is the main cause of blindness related to this disease. Current therapies do not provide enough protection and regeneration of RGCs. A novel opportunity for treatment of glaucoma is application of technologies related to stem cell and gene therapy. In this perspective we will thus focus on emerging approaches to glaucoma treatment including stem cells and gene therapy
The inhibition of Candida albicans secreted aspartyl proteinase by triangular gold nanoparticles
Objective(s): The aim of this study was to synthesize triangular gold nanoparticles, and then to evaluate their capability for inhibition of Candida albicans secreted aspartyl proteinase 2(Sap2). Materials and Methods: To synthesize the nanoparticles, hydrogen tetrachloroaurate and hexadecyl trimethyl ammonium bromide were incubated in presence of Sn(IV) meso-tetra(N-methyl-4-pyridyl) porphine tetratosylate chloride, and then characterized. Next, thirty clinical isolates of Candida albicans were obtained from patients suffering from vaginal candidiasis. Each Candida albicans isolate was first cultured in YCB-BSA medium, incubated for 24 h at 35 ºC. Then, 100 µL of triangular gold nanoparticles at three concentrations (16, 32, and 64 µg/mL) were added to Candida suspension, and incubated for 24 and 48 h at 35 ºC. To evaluate Sap activity, 0.1 mL of medium and 0.4 mL of 0.1 M sodium citrate buffer (pH 3.2) containing BSA 1% w/v were added, and incubated 15 minutes at 37 ºC. Then, the optical density of each tube was read at 280 nm. Enzyme activity was expressed as the amount (µM) of tyrosine equivalents released per min per ml of culture supernatant. Results: This study showed that the size of the nanoparticles was 70±50 nm. Sap activity evaluation demonstrated triangular gold nanoparticles could inhibit the enzyme, and the higher incubation time and concentration led to more decrease of Sap activity. Conclusion:For the first time, we demonstrated triangular gold nanoparticles as a novel inhibitor of Sap enzyme which may be useful for treatment of candidiasis.
Design and Production of A Wound Cover Containing Essence of Ajwain (Trachyspermum) by Nanoliposome Technique, and Assessment of Its Physical, Chemical, Antibacterial and Cytotoxicity Properties
Background and Aim: The aim of this study was to assess the applied characteristics of wound covers containing nanoliposomic essential oil of ajwain, with suitable antimicrobial properties and lack of cytotoxicity.
Materials and Methods: Liposomal formulations of the ajwain essential oil containing DSPE-PEG, cholesterol, span60 and SPC80 were prepared using a thin layer method. The rooting and spray methods on a cellulose fabric were used to produce skin wound cover. In addition to in vitro intracellular penetration and measurement of minimum inhibitory concentration of the product, textile characteristics, antimicrobial activity and 96 hours release of the essence in the wound cover were studied.
Ethical Considerations: In this study, all principles of research ethics were considered.
Findings: The loading efficiency of the liposomal formulation was more than 85%. The small particle dispersion index (PDI = 0.02) in the form of the PEGylated formulation indicates optimal dispersion of the particles which reduces the buildup of the drug in the cutaneous application. The standard AATCC microbial test showed inhibitory effect of the wound cover on bacteria, especially E. coli. Textile tests indicated acceptable properties of the produced wound cover, too.
Conclusion: Altogether, this wound cover showed acceptable features in combating the two selected bacteria responsible for infectious skin ulcers
Ectopic microRNAs used to preserve human mesenchymal stem cell potency and epigenetics
Human mesenchymal stem cells (hMSCs) have remarkable potential for use in regenerative medicine. However,
one of the great challenges is preserving their potency for long time. This study investigated the effect of miRNA
ectopic expression on their proliferation and also on the expression level of Parp1 as an epigenetic switch preserving
pluripotency in hMSCs. A cationic liposome was prepared as an efficient carrier for miRNA delivery.
The miRNA loading efficiency and physical stability of vesicles were measured, and their scanning electron microscopic
shapes determined. hMSCs were transfected with miR-302a and miR-34a followed by assessment of
their proliferation potency with MTT assay and measurement of the expression of Parp1 by quantitative polymerase
chain reaction (QPCR). Cell transfection with miR-302a and miR-34a efficiently and differentially affects
the proliferation potency of hMSCs and the expression level of Parp1 as the key epigenetic factor involved
in pluripotency. While miR-302a increases Parp1 expression, miR-34a suppresses it significantly, showing differential
effects. Our results demonstrated that miRNA-based treatments represent efficient therapeutic systems
and hold a great promise for future use in regenerative medicine through modification of hMSC pluripotency and
epigenome
Sex hormone levels and sexual dysfunction in men after coronary artery bypass graft
Background: Sexual dysfunction is one of the most common problems in
men after coronary artery bypass graft (CABG). Etiology of sexual
dysfunction in these patients may be psychological or organic due to
hormonal changes. Objective: The purpose was to evaluate the incidence
and type of sexual dysfunction and changes in serum concentration of
sex hormones in male patients undergoing on-pump CABG. Materials and
Methods: In this before and after study we enrolled 40 men aged less
than 70 years who were candidate for on-pump CABG. Interviews were done
by a physician before and 12 weeks after the operation in regard to the
impact of surgery on their sexual activities. The serum levels of 6 sex
hormones were also determined. The statistical tests used for data
analysis included analysis of variance, McNemar's test and chi-square
analysis. Results: The mean±SD age of the patients was
51.27±7.86 years. Incidence of sexual dysfunction was 22.5% (9
cases) before and 47.7% (19 cases) after operation. Types of sexual
dysfunction were premature ejaculation (5% before, 2.5% after),
impotence (7.5% before, 12.5% after) and loss of libido (10% before,
32% after). The level of sex hormones were generally decreased after
operation but it was statistically significant only for estrogen
(p-value=0.02). Conclusion: Sexual dysfunction and reduction in serum
level of sex hormones are common in patients before on-pump CABG and
mostly get worse after surgery. Complementary studies are suggested for
prevention and treatment of sexual dysfunction
Antimicrobial activity, toxicity and stability of phytol as a novel surface disinfectant
Background: Although various surface disinfectants have been introduced, most of them are toxic. The use of natural antimicrobial agent e.g. phytol, extracted from Leptadeniapyrotechnicais a new strategy. The aim of this study was to evaluate the antimicrobial activity, toxicity, and stability of phytol.
Methods: The serial concentrations of phytol were prepared, and separately incubated with four microbial isolates. Then, its Minimum Inhibitory Concentration (MIC) was measured for each microorganism. For toxicity test, serial concentrations (62.5, 125, 250, 500 and 1000 μg/mL) of phytol were incubated with mouse skin cells, and then cell viability was calculated by MTT assay. For stability test, three common surfaces (stone, steel, and MDF) were considered. Then, 100 μL of phytol was separately spread over their surface, and they have been kept at lab panel for 12, 24 and 36 hours. After incubation, two samples were obtained from each surface and inoculated on nutrient agar plates. Finally, colony count was read for each surface. T-test was used to evaluate the significant differences between groups, and P>0.05 considered as level of significant difference.
Results: The MIC50 of phytol against E.coli, C.albicans, and A.nigerwas 62.5 μg/mL, and against S.aureuswas >1000 μg/mL. MTT assay showed that the toxicity of phytol was dose and time dependent. The stability test demonstrated that phytol was stable on the stone, MDF, and steel surfaces until 36 hours.
Conclusion: It can be concluded that phytol has high antimicrobial activity, high stability, and low toxicity. This substance must be evaluated at actual conditions
Application of essential oil of Pistacia atlantica Gum, polypropylene and silica nanoparticles as a new milk packaging
The aim of current study was to investigate the antimicrobial effect of gum essential oil of Pistacia atlantica (wild pistachio) tree (GEO) and design a new film based on polypropylene polymer coated with silica nanoparticles and GEO. The antimicrobial activity of the packaging film was evaluated with or without milk on Staphylococcus aureus, Salmonella enterica, Escherichia coli, and Listeria monocytogenes during 35 days. The results showed that GEO has significant antibacterial properties. It was most effective on Salmonella enterica, while its effect on Listeria monocytogenes was the weakest. Antimicrobial activity of the film without milk showed no significant differences among the different sizes of nanoparticles used (0.05, 0.025, and 0.051 g) (p ≥ .05). It can be concluded that polypropylene incorporated with GEO and silica nanoparticles active film had antimicrobial properties up to 35 days, while using with milk or without milk. Therefore, this type of packaging is effective to enhance the shelf life of milk
Antimicrobial activity, toxicity and stability of phytol as a novel surface disinfectant
Abstract Background: Although various surface disinfectants have been introduced, most of them are toxic. The use of natural antimicrobial agent e.g. phytol, extracted from Leptadenia pyrotechnica is a new strategy. The aim of this study was to evaluate the antimicrobial activity, toxicity, and stability of phytol. Methods: The serial concentrations of phytol were prepared, and separately incubated with four microbial isolates. Then, its Minimum Inhibitory Concentration (MIC) was measured for each microorganism. For toxicity test, serial concentrations (62.5, 125, 250, 500 and 1000 µg/mL) of phytol were incubated with mouse skin cells, and then cell viability was calculated by MTT assay. For stability test, three common surfaces (stone, steel, and MDF) were considered. Then, 100 µL of phytol was separately spread over their surface, and they have been kept at lab panel for 12, 24 and 36 hours. After incubation, two samples were obtained from each surface and inoculated on nutrient agar plates. Finally, colony count was read for each surface. T-test was used to evaluate the significant differences between groups, and P>0.05 considered as level of significant difference. Results: The MIC50 of phytol against E.coli, C.albicans, and A.niger was 62.5 µg/mL, and against S.aureus was >1000 µg/mL. MTT assay showed that the toxicity of phytol was dose and time dependent. The stability test demonstrated that phytol was stable on the stone, MDF, and steel surfaces until 36 hours. Conclusion: It can be concluded that phytol has high antimicrobial activity, high stability, and low toxicity. This substance must be evaluated at actual conditions
Effect of zinc oxide nanoparticles on viability of human spermatozoa
Background: The extensive use of different nanoparticles has raised
great concerns about their occupational and biological safety.
Objective: The aim of this study was to evaluate the cytotoxic effect
of zinc oxide nanoparticles (ZnO NPs) on viability of spermatozoa.
Materials and Methods: Semen samples were obtained from 15 healthy
persons, and were analyzed using WHO guidelines. Each semen sample was
separately incubated with different concentrations of ZnO NPs (10, 100,
500, and 1000 μg/mL) at 37PoPC for 45, 90, and 180 minutes. Then,
the cell death percentage of spermatozoa was measured by MTT assay.
Mann-Whitney test was used for comparison of different times and
concentrations. Results: The maximum cell death percentage was 20.8%,
21.2%, and 33.2% after 45, 90, and 180 minutes, respectively. In case
of concentration, the highest concentration (1000 μg/mL) of ZnO
NPs led to the highest toxicity for all incubation times.
Statistically, there were significant differences in cell viability
after 180 minutes vs. 45 and 90 minutes. Conclusion: This study
indicated that cytotoxicity of ZnO NPs is dose and time dependent