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International Journal of Peptide Research and Therapeutics - RFamide-related Peptide-3(RFRP-3) plays a key role in appetite regulation. The current study aimed to determine the effect of...  相似文献   
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The Collembola fauna of Iran is little known and no comprehensive examination of this group of Hexapoda is available for this region. The only notable work on Collembola was carried out by Cox (1982). Recently, studies on the Collembola fauna have started in several regions. In this paper, publications by different researchers are documented and the species that have been found in different regions of Iran until January 2013 are listed. At present, 112 species, belonging to 18 families and 57 genera are known from Iran.  相似文献   
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Glioblastoma multiform (GBM) is known as an aggressive glial neoplasm. Recently incorporation of mesenchymal stem cells with anti-tumor drugs have been used due to lack of immunological responses and their easy accessibility. In this study, we have investigated the anti-proliferative and apoptotic activity of atorvastatin (Ator) in combination of mesenchymal stem cells (MSCs) on GBM cells in vitro and in vivo. The MSCs isolated from rats and characterized for their multi-potency features. The anti-proliferative and migration inhibition of Ator and MSCs were evaluated by MTT and scratch migration assays. The annexin/PI percentage and cell cycle arrest of treated C6 cells were evaluated until 72 h incubation. The animal model was established via injection of C6 cells in the brain of rats and subsequent injection of Ator each 3 days and single injection of MSCs until 12 days. The growth rate, migrational phenotype and cell cycle progression of C6 cells decreased and inhibited by the interplay of different factors in the presence of Ator and MSCs. The effect of Ator and MSCs on animal models displayed a significant reduction in tumor size and weight. Furthermore, histopathology evaluation proved low hypercellularity and mitosis index as well as mild invasive tumor cells for perivascular cuffing without pseudopalisading necrosis and small delicate vessels in Ator?+?MSCs condition. In summary, Ator and MSCs delivery to GBM model provides an effective strategy for targeted therapy of brain tumor.

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The extracellular matrix of different mammalian tissues is commonly used as scaffolds in the field of tissue engineering. One of these tissues, which has frequently been studied due to its structural and biological features, is the small intestine submucosal membrane. These research are mainly done on the porcine small intestine. However, a report has recently been published about a scaffold produced from the submucosal layer of the ovine small intestine. In the present study, ovine small intestine submucosal (OSIS) was decellularized in a modified manner and its histological, morphological, and biomechanical properties were studied. Decellularization was performed in two phases: physical and chemical. In this method, a chloroform-methanol mixture, enzymatic digestion, and a constant dose of sodium dodecyl sulfate (SDS) was used in the least agitation time and its histological property and biocompatibility were evaluated in the presence of adipose tissue-derived stem cells (ADSCs); furthermore, ADSCs were isolated with a simple method (modified physical washing non-enzymatic isolation). The results were showed that the use of OSIS could be effective and operative. Mechanical properties, histological structure and shape, and glycosaminoglycan content were preserved. In the SDS-treated group, more than 90% of the native cells of tissue were deleted, and also in this group, no toxicity was observed and cell proliferation was supported, compared to the untreated group. Therefore, our results indicate that ADSCs seeded on OSIS scaffold could be used as a new approach in regenerative medicine as hybrid or hydrogel application.  相似文献   
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Despite many advances and optimization in colon cancer treatment, tumor recurrence and metastases make the development of new therapies necessary. Colon cancer stem cells (CCSCs) are considered as the main triggering factor of cancer progression, recurrence, and metastasis. CCSCs as a result of accumulated genetic and epigenetic alterations and also complex interconnection with the tumor microenvironment (TME) can evolve and convert to full malignant cells. Mounting evidence suggests that in cancer therapy both CCSCs and non-CCSCs in TME have to be regarded to break through the limitation of current therapies. In this regard, stem cell capabilities of some non-CCSCs may arise inside the TME condition. Therefore, a deep knowledge of regulatory mechanisms, heterogeneity, specific markers, and signaling pathways of CCSCs and their interconnection with TME components is needed to improve the treatment of colorectal cancer and the patient's life quality. In this review, we address current different targeted therapeutic options that target cell surface markers and signaling pathways of CCSCs and other components of TME. Current challenges and future perspectives of colon cancer personalized therapy are also provided here. Taken together, based on the deep understanding of biology of CCSCs and using three-dimensional culture technologies, it can be possible to reach successful colon cancer eradication and improvise combination targeted therapies against CCSCs and TME.  相似文献   
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Exposing to sub-lethal and low lethal doses of pesticides may cause changes in natural enemy behavioural, such as functional, response. In this study, the effects of chlorpyrifos, carbaryl, abamectin and spinosad were evaluated on the functional response of the Habrobracon hebetor to different densities of last instar larvae of Anagasta kuehniella Zeller. Young adult females of the parasitoid were exposed to LC30 of chlorpyrifos, carbaryl, abamectin and spinosad that were 0.32, 4.03, 3.05 and 17.51?mg a.i./l for 24?h, respectively. Host densities of 2, 4, 8, 16, 32 and 64 were offered to treated young females for 2?h in 10-cm Petri dishes and then the parasitism data were recorded. Experiments were conducted in eight replications. Functional response type was determined using logistic regression and the parameters were appraised by non-linear regression using statistical analysis software. Functional response was type Ш in control and insecticide treatments. Searching efficiency in control, chlorpyrifos-, carbaryl-, abamectin- and spinosad-treated wasps were 0.008?±?0.002, 0.002?±?0.0009, 0.0034?±?0.0013, 0.0076?±?0.002 and 0.0073?±?0.002?h?1and handling times were 1.38?±?0.1, 7.64?±?1.01, 3.3?±?0.315, 1.55?±?0.1 and 1.46?±?0.11?h, respectively. Chlorpyrifos and carbaryl had the highest effect on searching efficiency of H. hebetor. Spinosad and abamectin showed less adverse effect on the functional response parameters. Finally, after conducting the advanced field studies, spinosad and abamectin may be used as a compatible chemical material with biological control agent in integrated pest management programmes.  相似文献   
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Functionalized carbon nanotubes (CNTs) constitute a new class of nanostructured materials that have vast applications in CNT purification and separation, biosensing, drug delivery, etc. Hybrids formed from the functionalization of CNT with biological molecules have shown interesting properties and have attracted great attention in recent years. Of particular interest is the hybridization of single- or double-stranded nucleic acid (NA) with CNT. Nucleobases, as the building blocks of NA, interact with CNT and contribute strongly to the stability of the NA–CNT hybrids and their properties. In this work, we present a thorough review of previous studies on the binding of nucleobases with graphene and CNT, with a focus on the simulation works that attempted to evaluate the structure and strength of binding. Discrepancies among these works are identified, and factors that might contribute to such discrepancies are discussed.  相似文献   
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