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1.
Naunyn Schmiedebergs Arch Pharmacol ; 396(1): 121-137, 2023 01.
Article in English | MEDLINE | ID: mdl-36255459

ABSTRACT

Biocompatibility of nanoparticles is the most essential factor in their use in clinical applications. In this study, hyperbranched spermine (HS), hyperbranched spermine-polyethylene glycol-folic acid (HSPF), and hyperbranched spermine-polyethylene glycol-glucose (HSPG) were synthesized for DNA protection and gene delivery to breast cancer cells. The synthesis of HSPG and HSPF was confirmed using proton nuclear magnetic resonance (H-NMR), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) spectroscopy. The HS/DNA, HSPF/DNA, HSPG/DNA, and hyperbranched spermine-polyethylene glycol-folic acid/glucose/DNA (HSPFG/DNA) nanoparticles were prepared by combining different concentrations of HS, HSPF, and HSPG with the same amount of DNA. The ability of HS, HSPF, and HSPG to interact with DNA and protect it against plasm digestion was evaluated using agarose gel. Moreover, in vivo and in vitro biocompatibility of HSPF/DNA, HSPG/DNA, and HSPFG/DNA was investigated using MTT assay and calculating weight change and survival ratio of BALB/c mice, respectively. The results of agarose gel electrophoresis showed that HS, HSPF, and HSPG have the high ability to neutralize the negative charge of DNA and protect it against plasma degradation. The results of in vivo cytotoxicity assay revealed that the HSPF/DNA, HSPG/DNA, and HSPFG/DNA nanoparticles have good biocompatibility on female BALB/c mice. In vitro and in vivo transfection assays revealed that functionalization of the surface of HS using polyethylene glycol-folic acid (HSPF) and polyethylene glycol-glucose (HSPG) significantly increases gene delivery efficiency in vitro and in vivo. These results also showed that gene transfer using both HSPF and HSPG copolymers increases gene transfer efficiency compared to when only one of them is used. The HSPFG/DNA nanoparticles have a high potential for use in therapeutic applications because of their excellent biocompatibility and high gene transfer efficiency to breast cancer tissue.


Subject(s)
Gene Transfer Techniques , Nanoparticles , Neoplasms , Animals , Female , Mice , DNA/chemistry , Folic Acid/chemistry , Glucose , Heparan Sulfate Proteoglycans , Nanoparticles/chemistry , Polyethylene Glycols/chemistry , Spermine/chemistry
2.
ACS Nano ; 16(8): 12107-12117, 2022 Aug 23.
Article in English | MEDLINE | ID: mdl-35862666

ABSTRACT

Lanthanide (Ln3+)-doped upconversion nanoparticles (UCNPs) often suffer from weak luminescence, especially when their sizes are ultrasmall (less than 10 nm). Enhancing the upconversion luminescence (UCL) efficiency of ultrasmall UCNPs has remained a challenge that must be undertaken if any practical applications are to be envisaged. Herein, we present a Ln3+-doped oxysulfide@fluoride core/shell heterostructure which shows efficient UCL properties under 980 nm excitation and good stability in solution. Through epitaxial heterogeneous growth, a ∼4 nm optically inert ß-NaYF4 shell was coated onto ∼5 nm ultrasmall Gd2O2S:20%Yb,1%Tm. These Gd2O2S:20%Yb,1%Tm@NaYF4 core/shell UCNPs exhibit a more than 800-fold increase in UCL intensity compared to the unprotected core, a 180-fold increase in luminescence decay time of the 3H4 → 3H6 Tm3+ transition from 5 to 900 µs, and an upconversion quantum yield (UCQY) of 0.76% at an excitation power density of 155 W/cm2. Likewise, Gd2O2S:20%Yb,2%Er@NaYF4 core/shell UCNPs show a nearly 5000-fold increase of their UCL intensity compared to the Gd2O2S:20%Yb,2%Er core and a maximum UCQY of 0.61%. In the Yb/Er core-shell UCNP system, the observed variation of luminescence intensity ratio seems to originate from a change in lattice strain as the temperature is elevated. For nanothermometry applications, the thermal sensitivities based on thermally coupled levels are estimated for both Yb/Tm and Yb/Er doped Gd2O2S@NaYF4 core/shell UCNPs.

3.
Adv Colloid Interface Sci ; 301: 102600, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35065336

ABSTRACT

The surface charge of calcite in aqueous environments is essential to many industrial and environmental applications. Electrokinetic measurements are usually used to assess the calcite charging behavior and characterize its electrical double layer (EDL). Numerous surface complexation models (SCMs) have been proposed to interpret the effect of different surface interactions on the zeta potential. Because of their versatility, SCMs have also become important tools in reactive transport modeling. The research on enhanced oil recovery within the last decade has led to an increased number of publications reporting both zeta potential measurements and SCMs for calcite. Nonetheless, the measurements are often inconsistent and the reasons for choosing one model over another are unclear. In this work, we review the models proposed for calcite and address their main differences. We first collect a large number of published zeta potential measurements and then we fit a Diffuse Layer, Basic Stern, and Charge-Distribution Multi-Site Complexation models to a selected reliable dataset. For each model, we maintain a similar number of adjustable parameters. After optimizing the parameters of the models, we systematically compare their prediction capabilities against data obtained in monovalent and divalent electrolyte systems containing calcium, magnesium, sulfate, or carbonate. We show that, often, the discrepancies between the models and the experimental data can be explained by different levels of disequilibrium. Nonetheless, assumptions used in the development of the models may significantly reduce their extrapolability to variable chemical conditions. The poor agreement between the models tuned to electrokinetic data with surface charge measurements and dynamic retention from single-phase flowthrough tests show that zeta potential may not be the best type of data to characterize ion binding at the calcite surface. Including the effect of mineral impurities and temperature on the calcite surface speciation and electrokinetic behavior prevail as main challenges for reactive transport modeling.


Subject(s)
Calcium Carbonate , Water , Calcium Carbonate/chemistry , Ions , Minerals , Water/chemistry
4.
Sci Rep ; 11(1): 829, 2021 Jan 12.
Article in English | MEDLINE | ID: mdl-33436884

ABSTRACT

A method based on the concept of exergy-return on exergy-investment is developed to determine the energy efficiency and CO2 intensity of polymer and surfactant enhanced oil recovery techniques. Exergy is the useful work obtained from a system at a given thermodynamics state. The main exergy investment in oil recovery by water injection is related to the circulation of water required to produce oil. At water cuts (water fraction in the total liquid produced) greater than 90%, more than 70% of the total invested energy is spent on injection and lift pumps, resulting in large CO2 intensity for the produced oil. It is shown that injection of polymer with or without surfactant can considerably reduce CO2 intensity of the mature waterflood projects by decreasing the volume of produced water and the exergy investment associated with its circulation. In the field examples considered in this paper, a barrel of oil produced by injection of polymer has 2-5 times less CO2 intensity compared to the baseline waterflood oil. Due to large manufacturing exergy of the synthetic polymers and surfactants, in some cases, the unit exergy investment for production of oil could be larger than that of the waterflooding. It is asserted that polymer injection into reservoirs with large water cut can be a solution for two major challenges of the energy transition period: (1) meet the global energy demand via an increase in oil recovery and (2) reduce the CO2 intensity of oil production (more and cleaner energy).

5.
Cell Biol Int ; 45(1): 127-139, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32997425

ABSTRACT

Follicular fluid (FF) is essential for developing ovarian follicles. Besides the oocytes, FF has abundant undifferentiated somatic cells containing stem cell properties, which are discarded in daily medical procedures. Earlier studies have shown that FF cells could differentiate into primordial germ cells via forming embryoid bodies, which produced oocyte-like cells (OLC). This study aimed at isolating mesenchymal stem cells (MSC) from FF and evaluating the impacts of bone morphogenetic protein 15 (BMP15) on the differentiation of these cells into OLCs. Human FF-derived cells were collected from 78 women in the assisted fertilization program and cultured in human recombinant BMP15 medium for 21 days. Real-time polymerase chain reaction and immunocytochemistry staining characterized MSCs and OLCs. MSCs expressed germline stem cell (GSC) markers, such as OCT4 and Nanog. In the control group, after 15 days, OLCs were formed and expressed zona pellucida markers (ZP2 and ZP3), and reached 20-30 µm in diameter. Ten days after induction with BMP15, round cells developed, and the size of OLCs reached 115 µm. A decrease ranged from 0.04 to 4.5 in the expression of pluripotency and oocyte-specific markers observed in the cells cultured in a BMP15-supplemented medium. FF-derived MSCs have an innate potency to differentiate into OLCs, and BMP15 is effective in promoting the differentiation of these cells, which may give an in vitro model to examine germ cell development.


Subject(s)
Bone Morphogenetic Protein 15/pharmacology , Cell Differentiation/drug effects , Follicular Fluid/cytology , Mesenchymal Stem Cells/cytology , Oocytes/cytology , Adipogenesis/drug effects , Biomarkers/metabolism , Bone Morphogenetic Protein 15/metabolism , Cell Proliferation/drug effects , Cell Shape/drug effects , Cells, Cultured , DNA/biosynthesis , Estradiol/biosynthesis , Female , Humans , Mesenchymal Stem Cells/drug effects , Oocytes/metabolism
6.
Sci Rep ; 9(1): 6072, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30988368

ABSTRACT

The few existing surface complexation models (SCM) for the brine-oil interface have important limitations: the chemistry of each crude oil is not considered, they cannot capture the water/non-polar hydrocarbons surface charge, the interactions between Na+ and the acid sites are not included, and the equilibrium constants for the adsorption reactions are not validated against experimental data. We address the aforementioned constraints by proposing an improved diffuse-layer SCM for the oil-brine interface. The new model accounts for the chemistry of crude oils by considering surface sites linearly dependent on the TAN (total acid number) and TBN (total base number). We define weak sites to account for the negative surface charge observed for non-polar hydrocarbons in water. We optimize the parameters of our model by fitting the model to reported zeta potential measurements of oil in aqueous solutions. When we validate the optimized model against different experimental data sets, it generally shows a good performance in predicting the surface charge of oil in different brines with different pHs. We show that the acid and base numbers are only useful as a qualitative estimation of the distribution of polar groups at the oil surface, and more sophisticated analysis is necessary to quantify the chemistry of the oil-brine interface.

7.
Iran J Otorhinolaryngol ; 31(102): 25-33, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30783596

ABSTRACT

INTRODUCTION: There is limited evidence regarding the quality of otolaryngology residency programs in Iran. Regarding this, the present study aimed to assess some aspects of otolaryngology residency program in the field of otology in Iran based on the perspectives of faculty members and graduates. MATERIALS AND METHODS: This study was conducted on 105 recent graduates and 30 faculty members and/or program directors in otolaryngology using two self-administered questionnaires. RESULTS: While the faculty members believed that a resident should work on at least 5.4 temporal bone surgeries on average, the actual number was 2.49. Tympanoplasty was assigned the highest rate of satisfaction by the recent graduates, whereas the lowest score belonged to middle ear exploration, ossiculoplasty, and stapes surgery. Only 53.6% of the graduates stated that there was an organized training curriculum in temporal laboratory. The recent graduates reported to have more frequent experiences of performing usual otology operations. However, they had fewer experiences of performing more advanced surgeries. The recently graduated subjects had a significantly low level of satisfaction with their competencies in carrying out more complex types of otology surgeries. CONCLUSION: High prevalence of otology surgeries in Iran provides valuable opportunities for training otolaryngology residents to achieve an acceptable level of competency. However, the results of this study strongly suggest the necessity of quality improvement both in teaching-learning and assessment processes in otolaryngology training programs.

8.
Sci Rep ; 7(1): 17482, 2017 12 13.
Article in English | MEDLINE | ID: mdl-29235501

ABSTRACT

Amorphous poly(ethylene ether carbonate) (PEEC), which is a copolymer of ethylene oxide and ethylene carbonate, was synthesized by ring-opening polymerization of ethylene carbonate. This route overcame the common issue of low conductivity of poly(ethylene oxide)(PEO)-based solid polymer electrolytes at low temperatures, and thus the solid polymer electrolyte could be successfully employed at the room temperature. Introducing the ethylene carbonate units into PEEC improved the ionic conductivity, electrochemical stability and lithium transference number compared with PEO. A cross-linked solid polymer electrolyte was synthesized by photo cross-linking reaction using PEEC and tetraethyleneglycol diacrylate as a cross-linking agent, in the form of a flexible thin film. The solid-state Li/LiNi0.6Co0.2Mn0.2O2 cell assembled with solid polymer electrolyte based on cross-linked PEEC delivered a high initial discharge capacity of 141.4 mAh g-1 and exhibited good capacity retention at room temperature. These results demonstrate the feasibility of using this solid polymer electrolyte in all-solid-state lithium batteries that can operate at ambient temperatures.

9.
ACS Appl Mater Interfaces ; 9(5): 4404-4419, 2017 Feb 08.
Article in English | MEDLINE | ID: mdl-27714999

ABSTRACT

Potassium may exhibit advantages over lithium or sodium as a charge carrier in rechargeable batteries. Analogues of Prussian blue can provide millions of cyclic voltammetric cycles in aqueous electrolyte. Potassium intercalation chemistry has recently been demonstrated compatible with both graphite and nongraphitic carbons. In addition to potassium-ion batteries, potassium-O2 (or -air) and potassium-sulfur batteries are emerging. Additionally, aqueous potassium-ion batteries also exhibit high reversibility and long cycling life. Because of potentially low cost, availability of basic materials, and intriguing electrochemical behaviors, this new class of secondary batteries is attracting much attention. This mini-review summarizes the current status, opportunities, and future challenges of potassium secondary batteries.

10.
J Chromatogr A ; 1466: 155-65, 2016 Sep 30.
Article in English | MEDLINE | ID: mdl-27634210

ABSTRACT

The present contribution is devoted to develop multivariate analytical figures of merit (AFOMs) as a new metric for evaluation of quantitative measurements using comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS). In this regard, new definition of sensitivity (SEN) is extended to GC×GC-MS data and then, other multivariate AFOMs including analytical SEN (γ), selectivity (SEL) and limit of detection (LOD) are calculated. Also, two frequently used second- and third-order calibration algorithms of multivariate curve resolution-alternating least squares (MCR-ALS) as representative of multi-set methods and parallel factor analysis (PARAFAC) as representative of multi-way methods are discussed to exploit pure component profiles and to calculate multivariate AFOMs. Different GC×GC-MS data sets with different number of components along with various levels of artifacts are simulated and analyzed. Noise, elution time shifts in both chromatographic dimensions, peak overlap and interferences are considered as the main artifacts in this work. Additionally, a new strategy is developed to estimate the noise level using variance-covariance matrix of residuals which is very important to calculate multivariate AFOMs. Finally, determination of polycyclic aromatic hydrocarbons (PAHs) in aromatic fraction of heavy fuel oil (HFO) analyzed by GC×GC-MS is considered as real case to confirm applicability of the proposed metric in real samples. It should be pointed out that the proposed strategy in this work can be used for other types of comprehensive two-dimensional chromatographic (CTDC) techniques like comprehensive two dimensional liquid chromatography (LC×LC).


Subject(s)
Chemistry Techniques, Analytical/methods , Chemistry Techniques, Analytical/standards , Gas Chromatography-Mass Spectrometry , Algorithms , Calibration , Fuel Oils/analysis , Gas Chromatography-Mass Spectrometry/standards , Least-Squares Analysis , Limit of Detection , Multivariate Analysis , Polycyclic Aromatic Hydrocarbons/analysis
11.
J Nanosci Nanotechnol ; 16(6): 5856-64, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27427644

ABSTRACT

A new size dependence kinetic equation for chain growth factor in Fischer-Tropsch synthesis (FTS) was developed using a thermodynamic analysis method. For evaluation of structural sensitivity of FTS reaction, a series of iron oxide nanoparticles were prepared as a catalyst via precipitation by microemulsion method. The experimental results indicated that the difference between activation energies for propagation and termination reactions (Et-Ep) decreased with decreasing the catalyst particle size. Calculated size dependent model parameters were employed for evaluation of surface tension energy (σ) and size-independent activation energy for chain growth probabilities.

12.
Langmuir ; 32(25): 6239-45, 2016 06 28.
Article in English | MEDLINE | ID: mdl-27244300

ABSTRACT

We present the results of an experimental investigation of the effect of gas type and composition on foam transport in porous media. Steady-state foam strengths with respect to three cases of distinct gases and two cases containing binary mixtures of these gases were compared. The effects of gas solubility, the stability of lamellae, and the gas diffusion rate across the lamellae were examined. Our experimental results showed that the steady-state foam strength is inversely correlated with the gas permeability across a liquid lamella, a parameter that characterizes the rate of mass transport. The results are also in good agreement with existing observations that the foam strength for a mixture of gases is correlated with the less soluble component. Three hypotheses with different predictions of the underlying mechanism that explain the role of gas type and composition in foam strength are discussed in detail.

13.
Environ Monit Assess ; 187(1): 4129, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25404541

ABSTRACT

Vortex-assisted surfactant-enhanced emulsification microextraction based on solidification of floating organic drop (VASEME-SFO) was used for preconcentration and speciation of antimony (ΙΙΙ, V) followed by electrothermal atomic absorption spectrometry (ETAAS). In this procedure, Triton X-114 was used as emulsifier and 1-undecanol was used as extraction solvent. This method is based on the complexation of Sb(ΙΙΙ) with dithizone (as complexing agent) at pH 2 and extraction of the resulting hydrophobic complex into the extraction solvent (1-undecanol) with vortex-assisted liquid phase microextraction, whereas Sb(V) remained in solution. Sb(ΙΙΙ) in extraction solvent was directly analyzed by ETAAS after dilution with ethanol, and Sb(V) was calculated by subtracting Sb(ΙΙΙ) from the total antimony after reducing Sb(V) to Sb(ΙΙΙ) by L-cysteine. Under the optimized condition, the calibration curve was linear in the range of 0.4-8 µg L(-1) of Sb(ΙΙΙ) with a correlation coefficient of 0.9995. The detection limit based on three times of the standard deviation of the blank (n = 8) was 0.09 µg L(-1). The validation and the recovery of the proposed method were performed by the analysis of a certified reference material and spike method. The obtained results were in very good agreements with certified values. The proposed method was successfully applied for the determination of antimony species at trace levels in different water samples.


Subject(s)
Antimony/analysis , Chemical Fractionation/methods , Antimony/chemistry , Calibration , Environmental Monitoring , Limit of Detection , Liquid Phase Microextraction , Models, Chemical , Octoxynol , Polyethylene Glycols/chemistry , Spectrophotometry, Atomic/methods , Surface-Active Agents/chemistry
14.
Iran J Psychiatry Behav Sci ; 9(4): e2446, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26834806

ABSTRACT

BACKGROUND: Today, domestic violence against women is a growing epidemic that can be observed in many countries. OBJECTIVES: This study was carried out to determine the types of domestic violence against women who were referred to the Legal Medical Organization of Iran in Urmia, Iran in 2012. MATERIALS AND METHODS: The descriptive survey included demographic information, abuse screening, and items regarding partner involvement. Data was gathered using face-to-face structured interviews. The study population included 300, women 18 years of age or older, and data was collected about their demographic characteristics and the types of domestic violence they experienced. SPSS software version 16 was used for the analyses. RESULTS: The majority of participants were in the 25 - 30 age group, and 83% of them were battered by their husbands in various ways. No significant relationships were observed between violence and unemployment, increasing age, and home ownership. CONCLUSIONS: The prevalence of abuse reported by women in this population suggests that many women that are referred to the Legal Medical Organization of Iran may have a history of abuse. Abused women may have different reasons for seeking a divorce. If routine screening for abuse is included in counseling, health providers will have the opportunity to develop a safety plan and initiate appropriate referrals.

15.
Environ Monit Assess ; 185(11): 9067-75, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23649476

ABSTRACT

Highly rapid and selective vortex-assisted liquid-liquid microextraction based on solidification of organic drop has been used for determination of cobalt ion. 2-Nitroso-1-naphthol (2N1N) was used as a selective complexing agent to form stable cobalt-2N1N complex which can be extracted with 1-undecanol at a short time by the assistance of vortex agitator system followed by its determination using flame atomic absorption spectrometry. In vortex assisted, vigorous vortex stream as well as the vibrant effect of vortex system cause very fine droplets of extraction solvent to be produced and extraction occurred at a short time. Some parameters influencing the extraction process such as pH of samples, concentration of 2-nitroso-1-naphthol, extraction solvent volume, extraction time, ionic strength and surfactant addition, as well as interferences were evaluated in detail and optimum conditions were selected. At the optimum conditions, the calibration curve was linear in the range of 15 to 400 µg L(-1) of cobalt ions. The relative standard deviation based on ten replicate analysis of sample solution containing 50 µg L(-1) of cobalt was 3.4%. The detection limit (calculated as the concentration equivalent to three times of the standard deviation of the blank divided by the slope of the calibration curve after preconcentration) was 5.4 µg L(-1). The accuracy of the proposed method was successfully evaluated by the analysis of certified reference materials. This selective and highly rapid method was used for determination of cobalt ions in different water samples.


Subject(s)
Cobalt/analysis , Liquid Phase Microextraction/methods , Nitroso Compounds/chemistry , Water Pollutants, Chemical/analysis , Cobalt/chemistry , Spectrophotometry, Atomic , Water Pollutants, Chemical/chemistry
16.
Arch Iran Med ; 15(5): 317-9, 2012 May.
Article in English | MEDLINE | ID: mdl-22519383

ABSTRACT

BACKGROUND: On January 9, 2011 Iran Air Flight 277 crashed during approach to Urmia, Iran. Out of 105 passengers, 27 survived. This brief report presents a perspective of the passengers' sustained injuries. METHODS: We reviewed the recorded injuries of all passengers as provided by the Legal Medicine Organization authorities. The Injury Severity Score (ISS), an anatomical scoring system, was used to provide an overall code for those who survived with multiple anatomical injuries. RESULTS: There were a total of 96 ISS body region injuries among those who survived. Facial injuries (83%) were the most frequent injuries noted among fatalities, which was statistically significant (P = 0.000). In those who survived, injuries to the head and neck (37%) and facial (33%) regions were relatively less frequent than other anatomical regions. The most serious injuries among survivors belonged to the extremity (85%) region, particularly lower limb fractures (62%). Differences in extremity injuries between the survivors and fatalities were not statistically significant. CONCLUSION: The findings of this study were similar to other studies where the most frequent serious injuries were fractures of the extremities, particularly the lower limbs.


Subject(s)
Accidents, Traffic , Injury Severity Score , Facial Injuries , Fractures, Bone , Humans , Iran
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