Inhibition of Leptin and Leptin Receptor Gene Expression by Silibinin-Curcumin Combination

Nejati-Koshki, Kazem,Akbarzadeh, Abolfazl,Pourhasan-Moghaddam, Mohammad,Abhari, Alireza,Dariushnejad, Hassan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Leptin and its receptor are involved in breast carcinogenesis as mitogenic factors. Therefore, they could be considered as targets for breast cancer therapy. Expression of the leptin receptor gene could be modulated by leptin secretion. Silibinin and curcumin are herbal compounds with anti-cancer activity against breast cancer. The aim of this study was to assess their potential to inhibit of expression of the leptin gene and its receptor and leptin secretion. Cytotoxic effects of the two agents on combination on T47D breast cancer cells was investigated by MTT assay test after 24h treatment. With different concentrations the levels of leptin, leptin receptor genes expression were measured by reverse-transcription real-time PCR. Amount of secreted leptin in the culture medium was determined by ELISA. Data were statistically analyzed by one-way ANOVA test. The silibinin and curcumin combination inhibited growth of T47D cells in a dose dependent manner. There were also significant difference between control and treated cells in leptin expression and the quantity of secreted leptin with a relative decrease in leptin receptor expression. In conclusion, these herbal compounds inhibit the expression and secretion of leptin and it could probably be used as drug candidates for breast cancer therapy through leptin targeting in the future.

Effects of fiber orientation and temperature on natural frequencies of a functionally graded beam reinforced with fiber

Mohammad Nejati,Keramat Malekzadeh Fard,Amir Hossein Eslampanah 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.8

In this paper, thermal vibrations of a reinforced orthotropic beam are studied. The beam is reinforced with fibers functionally orientedand graded along the thickness direction. Uniform thermal distribution is applied throughout the beam and property of the fiber functionallygraded beam considered temperature-dependent. Symmetrical, asymmetrical, and classical distributions are presented for variabilityof the angle of the fibers along the thickness direction. Equilibrium equations are employed to obtain the pre-stresses and equations ofmotion derived from first-order shear deformation theory and Hamilton principle. Generalized differential quadrature is used to solve thesystem of coupled differential equations. To verify the accuracy of the present analysis, compression is conducted with valid data. Resultsshow that different parameters, such as thickness-to-radius ratio, effect of temperature variations, distribution of the angle of the fibers,and different boundary conditions, influenced the beam effect on natural frequencies.

TRANSITION LOCATION EFFECTS ON DRAG REDUCTION FOR AIRSHIP BODIES

Vahid NEJATI,Kazuo MATSUUCHI 한국전산유체공학회 2003 한국전산유체공학회 학술대회논문집 Vol.2003 No.10

Effect of brittleness on the micromechanical damage and failure pattern of rock specimens

Hamid Reza Nejati,Mehrdad Imani,Kamran Goshtasbi,Amin Nazerigivi 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.29 No.4

Failure patterns of rock specimens represent valuable information about the mechanical properties and crack evolution mechanism of rock. Several kinds of research have been conducted regarding the failure mechanism of brittle material, however; the influence of brittleness on the failure mechanism of rock specimens has not been precisely considered. In the present study, experimental and numerical examinations have been made to evaluate the physical and mechanical phenomena associated with rock failure mechanisms through the uniaxial compression test. In the experimental part, Unconfined Compressive Strength (UCS) tests equipped with Acoustic Emission (AE) have been conducted on rock samples with three different brittleness. Then, the numerical models have been calibrated based on experimental test results for further investigation and comparing the micro-cracking process in experimental and numerical models. It can be perceived that the failure mode of specimens with high brittleness is tensile axial splitting, based on the experimental evidence of rock specimens with different brittleness. Also, the crack growth mechanism of the rock specimens with various brittleness using discrete element modeling in the numerical part suggested that the specimens with more brittleness contain more tensile fracture during the loading sequences.

Monitoring of fracture propagation in brittle materials using acoustic emission techniques-A review

Hamid Reza Nejati,Amin Nazerigivi,Mehrdad Imani,Ali Karrech 사단법인 한국계산역학회 2020 Computers and Concrete, An International Journal Vol.25 No.1

During the past decades, the application of acoustic emission techniques (AET) through the diagnosis and monitoring of the fracture process in materials has been attracting considerable attention. AET proved to be operative among the other non-destructive testing methods for various reasons including their practicality and cost-effectiveness. Concrete and rock structures often demand thorough and real-time assessment to predict and prevent their damage nucleation and evolution. This paper presents an overview of the work carried out on the use of AE as a monitoring technique to form a comprehensive insight into its potential application in brittle materials. Reported properties in this study are crack growth behavior, localization, damage evolution, dynamic character and structures monitoring. This literature review provides practicing engineers and researchers with the main AE procedures to follow when examining the possibility of failure in civil/resource structures that rely on brittle materials.

Inhibitory Effects of β-Cyclodextrin-Helenalin Complexes on H-TERT Gene Expression in the T47D Breast Cancer Cell Line - Results of Real Time Quantitative PCR

Ghasemali, Samaneh,Nejati-Koshki, Kazem,Akbarzadeh, Abolfazl,Tafsiri, Elham,Zarghami, Nosratollah,Rahmati-Yamchi, Mohamad,Alizadeh, Effat,Barkhordari, Amin,Tozihi, Majid,Kordi, Shirafkan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Background: Nowadays, the encapsulation of cytotoxic chemotherapeutic agents is attracting interest as a method for drug delivery. We hypothesized that the efficiency of helenalin might be maximized by encapsulation in ${\beta}$-cyclodextrin nanoparticles. Helenalin, with a hydrophobic structure obtained from flowers of Arnica chamissonis and Arnica Montana, has anti-cancer and anti-inflammatory activity but low water solubility and bioavailability. ${\beta}$-Cyclodextrin (${\beta}$-CD) is a cyclic oligosaccharide comprising seven D-glucopyranoside units, linked through 1,4-glycosidic bonds. Materials and Methods: To test our hypothesis, we prepared ${\beta}$-cyclodextrin-helenalin complexes to determine their inhibitory effects on telomerase gene expression by real-time polymerase chain reaction (q-PCR) and cytotoxic effects by colorimetric cell viability (MTT) assay. Results: MTT assay showed that not only ${\beta}$-cyclodextrin has no cytotoxic effect on its own but also it demonstrated that ${\beta}$-cyclodextrin-helenalin complexes inhibited the growth of the T47D breast cancer cell line in a time and dose-dependent manner. Our q-PCR results showed that the expression of telomerase gene was effectively reduced as the concentration of ${\beta}$-cyclodextrin-helenalin complexes increased. Conclusions: ${\beta}$-Cyclodextrin-helenalin complexes exerted cytotoxic effects on T47D cells through down-regulation of telomerase expression and by enhancing Helenalin uptake by cells. Therefore, ${\beta}$-cyclodextrin could be superior carrier for this kind of hydrophobic agent.

PAMAM Dendrimers Augment Inhibitory Effects of Curcumin on Cancer Cell Proliferation: Possible Inhibition of Telomerase

Mollazade, Mahdie,Nejati-Koshki, Kazem,Akbarzadeh, Abolfazl,Zarghami, Nosratollah,Nasiri, Marzieh,Jahanban-Esfahlan, Rana,Alibakhshi, Abbas Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Background: Despite numerous useful anticancer properties of curcumin, its utility is limited due to its hydrophobic structure. In this study, we investigated the comparative antiproliferative effect of PAMAM encapsulating curcumin with naked curcumin on the T47D breast cancer cell line. Materials and Methods: Cytotoxic effects of PAMAM dendrimers encapsulating curcumin and curcumin alone were investigated by MTT assay. After treating cells with different concentrations of both curcumin alone and curcumin encapsulated for 24h, telomerase activity was determined by TRAP assay. Results: While PAMAM dendrimers encapsulating curcumin had no cytotoxicity on cancer cells, they decreased the $IC_{50}$ for proliferation and also increased the inhibitory effect on telomerase activity. Conclusions: Considering the non-toxicity in addition to effectiveness for enhancing curcumin anticancer properties, dendrimers could be considered good therapeutic vehicles for this hydrophobic agent.

Estimation of Genetic Variation in Holstein Young Bulls of Iran AI Station Using Molecular Markers

Rahimi, G.,Nejati-Javaremi, A.,Saneei, D.,Olek, K. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.4

Genetic profiles of Iranian Holstein young bulls at the national artificial insemination station were determined on the basis of individual genotypes at 13 ISAG's recommended microsatellites, the most useful markers of choice for parentage identification. In the present study a total of 119 individuals were genotyped at 13 microsatellite loci and for possible parent-offspring combinations. A high level of genetic variation was evident within the investigated individuals as assessed from various genetic diversity measures. The mean number of observed alleles per microsatellite marker was 9.15 and the number of effective alleles as usual was less than the observed values (4.03). The average observed and expected heterozygosity values were 0.612 and 0.898, respectively. The mean polymorphic information content (PIC) value (0.694) further reflected a high level of genetic variability. The average exclusion of probability (PE) of the 13 markers was 0.520, ranging from 0.389 to 0.788. The combined exclusion of probability was 0.999, when 13 microsatellite loci were used for analysis in the individual identification system. Inbreeding was calculated as the difference between observed and expected heterozygosity. Observed homozygosity was less than expected which reflects inbreeding of -3.7% indicating that there are genetic differences between bull-sires and bull-dams used to produce young bulls. The results obtained from this study demonstrate that the microsatellite DNA markers used in the present DNA typing are useful and sufficient for individual identification and parentage verification without accurate pedigree information.

Influence of nano-silica on the failure mechanism of concrete specimens

Amin Nazerigivi,Hamid Reza Nejati,Abdolhadi Ghazvinian,Alireza Najigivi 사단법인 한국계산역학회 2017 Computers and Concrete, An International Journal Vol.19 No.4

Failure of basic structures material is usually accompanied by expansion of interior cracks due to stress concentration at the cracks tip. This phenomenon shows the importance of examination of the failure behavior of concrete structures. To this end, 4 types of mortar samples with different amounts of nano-silica (0%, 0.5%, 1%, and 1.5%) were made to prepare twelve 50×50×50 mm cubic samples. The goal of this study was to describe the failure and micro-crack growth behavior of the cement mortars in presence of nano-silica particles and control mortars during different curing days. Failure of mortar samples under compressive strength were sensed with acoustic emission technique (AET) at different curing days. It was concluded that the addition of nano-silica particles could modify failure and micro-crack growth behavior of mortar samples. Also, monitoring of acoustic emission parameters exposed differences in failure behavior due to the addition of the nanoparticles. Mortar samples of nano-silica particles revealed stronger shear mode characteristics than those without nanoparticles, which revealed high acoustic activity due to heterogeneous matrix. It is worth mentioning that the highest compressive strength for 3 and 7 test ages obtained from samples with the addition of 1.5% nano-silica particles. On the other hand maximum compressive strength of 28 curing days obtained from samples with 1% combination of nano-silica particles.

Physicochemical Characteristics of Fe₃O₄ Magnetic Nanocomposites Based on Poly(N-isopropylacrylamide) for Anti-cancer Drug Delivery

Davaran, Soodabeh,Alimirzalu, Samira,Nejati-Koshki, Kazem,Nasrabadi, Hamid Tayefi,Akbarzadeh, Abolfazl,Khandaghi, Amir Ahmad,Abbasian, Mojtaba,Alimohammadi, Somayeh Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Background: Hydrogels are a class of polymers that can absorb water or biological fluids and swell to several times their dry volume, dependent on changes in the external environment. In recent years, hydrogels and hydrogel nanocomposites have found a variety of biomedical applications, including drug delivery and cancer treatment. The incorporation of nanoparticulates into a hydrogel matrix can result in unique material characteristics such as enhanced mechanical properties, swelling response, and capability of remote controlled actuation. Materials and Methods: In this work, synthesis of hydrogel nanocomposites containing magnetic nanoparticles are studied. At first, magnetic nanoparticles ($Fe_3O_4$) with an average size 10 nm were prepared. At second approach, thermo and pH-sensitive poly (N-isopropylacrylamide -co-methacrylic acid-co-vinyl pyrrolidone) (NIPAAm-MAA-VP) were prepared. Swelling behavior of co-polymer was studied in buffer solutions with different pH values (pH=5.8, pH=7.4) at $37^{\circ}C$. Magnetic iron oxide nanoparticles ($Fe_3O_4$) and doxorubicin were incorporated into copolymer and drug loading was studied. The release of drug, carried out at different pH and temperatures. Finally, chemical composition, magnetic properties and morphology of doxorubicin-loaded magnetic hydrogel nanocomposites were analyzed by FT- IR, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM). Results: The results indicated that drug loading efficiency was increased by increasing the drug ratio to polymer. Doxorubicin was released more at $40^{\circ}C$ and in acidic pH compared to that $37^{\circ}C$ and basic pH. Conclusions: This study suggested that the poly (NIPAAm-MAA-VP) magnetic hydrogel nanocomposite could be an effective carrier for targeting drug delivery systems of anti-cancer drugs due to its temperature sensitive properties.