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991.
Breast cancer is a malignancy that affects mostly females and is among the most lethal types of cancer. The ligand-functionalized nanoparticles used in the nano-drug delivery system offer enormous potential for cancer treatments. This work devised a promising approach to increase drug loading efficacy and produce sustained release of 5-fluorouracil (5-FU) and Ganoderic acid (GA) as model drugs for breast cancer. Chitosan, aptamer, and carbon quantum dot (CS/Apt/COQ) hydrogels were initially synthesized as a pH-sensitive and biocompatible delivery system. Then, CS/Apt/COQ NPs loaded with 5-FU-GA were made using the W/O/W emulsification method. FT-IR, XRD, DLS, zeta potentiometer, and SEM were used to analyze NP's chemical structure, particle size, and shape. Cell viability was measured using MTT assays in vitro using the MCF-7 cell lines. Real-time PCR measured cell apoptotic gene expression. XRD and FT-IR investigations validated nanocarrier production and revealed their crystalline structure and molecular interactions. DLS showed that nanocarriers include NPs with an average size of 250.6 nm and PDI of 0.057. SEM showed their spherical form, and zeta potential studies showed an average surface charge of +37.8 mV. pH 5.4 had a highly effective and prolonged drug release profile, releasing virtually all 5-FU and GA in 48 h. Entrapment efficiency percentages for 5-FU and GA were 84.7±5.2 and 80.2 %±2.3, respectively. The 5-FU-GA-CS-CQD-Apt group induced the highest cell death, with just 57.9 % of the MCF-7 cells surviving following treatment. 5-FU and GA in CS-CQD-Apt enhanced apoptotic induction by flow cytometry. 5-FU-GA-CS-CQD-Apt also elevated Caspase 9 and downregulated Bcl2. Accordingly, the produced NPs may serve as pH-sensitive nano vehicles for the controlled release of 5-FU and GA in treating breast cancer.  相似文献   
992.
I Seif  J De Maeyer-Guignard 《Gene》1986,43(1-2):111-121
A new murine alpha interferon gene, MuIFN-alpha I9, isolated from a BALB/c genomic clone, was characterized. It encodes a mature polypeptide of 167 amino acids (aa), presenting from 77 to 86% homology with the seven other MuIFN-alpha I aa sequences previously described. When compared to the latter, pre-IFN-alpha I9 has 13 distinctive aa, and, remarkably, ten of these occur in pairs. The coding region, fused to the SV40 early promoter and introduced into COS monkey cells, directed the transient secretion of an acid-stable functional IFN of 18-21 kDa. The production in this system reached levels of 300 000 units per 0.15 ml. A comparison of the aa sequence of different murine, rat, bovine, and human alpha and beta IFNs revealed certain common features allowing us to propose a putative secondary structure of the IFN proteins. A detailed analysis of results previously published by us and by others showed that the MuIFN-alpha I9 gene is, together with a least twelve other MuIFN-alpha I genes, located on chromosome 4.  相似文献   
993.

Label-free detection of biomarkers has been recently noticed and optical biosensors showed great potential to be the method of choice in such situation. Here, we used glancing angle deposition (GLAD) method in which silver nano-columns stabilized by a self-assembled monolayer (SAM) of 11-mercaptoundecanoic acid (MUA) and 6-mercaptohexanol to investigate the capability of localized surface plasmon resonance (LSPR)–based silver nanochips to detect prostate-specific antigen (PSA). Using different standard solutions of PSA, limit of detection (LOD) of the nano-sensors has been calculated to be 850 pg/ml. The selectivity of the nano-sensors has also been evaluated. We showed that these nano-sensors could detect PSA in clinically acceptable sensitivity and specificity without any complicated laboratory equipment.

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994.

To encapsulate piperine (Pip), as a poor water-soluble bioactive compound, zein-sodium caseinate-xanthan gum (Z-SG-XG) nanocomplex was prepared as a colloidal delivery system. The effect of different parameters involved in complexation process, including concentration of proteins, polysaccharide, and Pip on the encapsulation efficiency of Pip, particle size and stability of the nanocomplexes was investigated. Powders obtained by freeze-drying of the colloidal solution had relatively uniform particles compared to those obtained from conventional drying system and showed well redispersibility in water. At the optimal condition, a stable and homogeneous nanocomplex with a mean particle size of 145.9 ± 2.7 nm, PDI of 0.27 ± 0.01, and ζ-potential of −39.7 ± 1.3 mV was obtained. The antioxidant activity of Pip was significantly improved by encapsulation into the Z-SC-XG nanocomplex. Also, the in vitro release of Pip from the synthesized nanocomplexes in phosphate-buffer saline (PBS) solution and simulated gastrointestinal fluids (SGIF) was investigated and the release kinetic was studied as well. The Pip/Z-SG-XG nanocomplex showed a slower release in SGIF compared to the free Pip and nanoparticles without XG and SC, while its antioxidant activity was remarkable. Results suggested a possible utilization of Z-SC-XG nanocomplex for improving the water solubility, bioavailability and storage stability of Pip.

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995.
Tropisetron exerts a protective effect against cardiac complications, particularly cardiac hypertrophy. Oxidative stress and apoptosis are the main contributors to the pathogenesis of cardiac hypertrophy. Sirtuins, a family of histone deacetylases, are connected to cellular oxidative stress signaling and antioxidant defense. Sirtuins are also linked to apoptosis which is an important mechanism in the progression of cardiac hypertrophy to heart failure. Literature also suggests that tropisetron impedes apoptosis, partly mediated through an antioxidant mechanism. Therefore, we examined if tropisetron fights cardiac hypertrophy by adjusting sirtuin family proteins (Sirts) and components of mitochondrial death pathway, Bcl-associated X (BAX), Bcl-2-associated death promoter (BAD). Male Sprague–Dawley rats got divided into four groups, including control (Ctl), tropisetron (Trop), cardiac hypertrophy (Hyp), and hypertrophic rats under tropisetron treatment (Hyp + Trop). Pathological cardiac hypertrophy was induced by surgical abdominal aortic constriction (AAC). The increased expression of brain natriuretic peptide (BNP) in the Hyp group confirms the cardiac hypertrophy establishment. The mRNA levels of SIRT1, SIRT3, SIRT7, and BAD also upregulated in the hypertrophic group (p < 0.001). Postoperational administration of tropisetron for 3 weeks lowered the increased expression of BNP (p < 0.05) and BAD (p < 0.001), though the reduction of BAX expression was statistically insignificant (p > 0.05). Tropisetron treatment also restored the normal level of SIRT1/3/7 genes expression in the Hyp + Trop group (p < 0.05). Present findings suggest that tropisetron can suppress cardiomyocyte hypertrophy progression to heart failure by counteracting BNP, SIRT1, SIRT3, Sirt7, and BAD overexpression-mediated apoptosis in a rat model of cardiac hypertrophy.  相似文献   
996.
A computational method is developed to allow molecular dynamics simulations of biomembrane systems under realistic ionic gradients and asymmetric salt concentrations while maintaining the conventional periodic boundary conditions required to minimize finite-size effects in an all-atom explicit solvent representation. The method, which consists of introducing a nonperiodic energy step acting on the ionic species at the edge of the simulation cell, is first tested with illustrative applications to a simple membrane slab model and a phospholipid membrane bilayer. The nonperiodic energy-step method is then used to calculate the reversal potential of the bacterial porin OmpF, a large cation-specific β-barrel channel, by simulating the I-V curve under an asymmetric 10:1 KCl concentration gradient. The calculated reversal potential of 28.6 mV is found to be in excellent agreement with the values of 26–27 mV measured from lipid bilayer experiments, thereby demonstrating that the method allows realistic simulations of nonequilibrium membrane transport with quantitative accuracy. As a final example, the pore domain of Kv1.2, a highly selective voltage-activated K+ channel, is simulated in a lipid bilayer under conditions that recreate, for the first time, the physiological K+ and Na+ concentration gradients and the electrostatic potential difference of living cells.  相似文献   
997.
Molecular Biology Reports - Prodiginines are bacterial red polypyrrole pigments and multifaceted secondary metabolites. These agents have anti-proliferative, immunosuppressive, antimicrobial, and...  相似文献   
998.
Today, bacterial cellulose has received a great deal of attention for its medical applications due to its unique structural properties such as high porosity, good fluid uptake, good strength, and biocompatibility. This study aimed to fabricate and study bacterial cellulose/graphitic carbon nitride/nettles/trachyspermum nanocomposite by immersion and PVA/BC/g-C3N4/nettles/trachyspermum nanofiber by electrospinning method as a wound dressing. The g-C3N4 and g-C3N4 solution were synthesized and then were characterized using Fourier transform infrared, X-ray diffraction, Zeta Potential, and scanning electronic microscope analyzes. Also, the antibacterial properties of the synthesized materials were proved by gram-positive and gram-negative bacteria using the minimum inhibitory concentration method. Besides, the toxicity, migration, and cell proliferation results of the synthesized materials on NIH 3T3 fibroblasts were evaluated using MTT and scratch assays and showed that the BC/PVA/g-C3N4/nettles/trachyspermum composite not only had no toxic effect on cells but also contributed to cell survival, cell migration, and proliferation has done. To evaluate the mechanical properties, a tensile strength test was performed on PVA/BC/g-C3N4/nettles/trachyspermum nanofibers, and the results showed good strength of the nanocomposite. In addition, in vivo assay, the produced nanofibers were used to evaluate wound healing, and the results showed that these nanofibers were able to accelerate the wound healing process so that after 14 days, the wound healing percentage showed 95%. Therefore, this study shows that PVA/BC/g-C3N4/nettles/trachyspermum nanofibers effectively inhibit bacterial growth and accelerate wound healing.  相似文献   
999.
Majed  Ali  Raji  Fatemeh  Miri  Ali 《Cluster computing》2022,25(1):401-416

Data availability represents one of the primary functionalities of any cloud storage system since it ensures uninterrupted access to data. A common solution used by service providers that increase data availability and improve cloud performance is data replication. In this paper, we present a dynamic data replication strategy that is based on a hybrid peer-to-peer cloud architecture. Our proposed strategy selects the most popular data for replication. To determine the proper nodes for storing popular data, we employ not only the feature specifications of storage nodes, but also the relevant structural positions in the cloud network. Our simulation results show the impact of using features such as data popularity, and structural characteristics in improving network performance and balancing the storage nodes, and reducing user response time.

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1000.
Cell-based immunotherapies have been selected for the front-line cancer treatment approaches. Among them, CAR-T cells have shown extraordinary effects in hematologic diseases including chemotherapy-resistant acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), and non-Hodgkin lymphoma (NHL). In this approach, autologous T cells isolated from the patient''s body genetically engineered to express a tumor specific synthetic receptor against a tumor antigen, then these cells expanded ex vivo and re-infusion back to the patient body. Recently, significant clinical response and high rates of complete remission of CAR T cell therapy in B-cell malignancies led to the approval of Kymriah and Yescarta (CD19-directed CAR-T cells) were by FDA for treatment of acute lymphoblastic leukemia and diffuse large B-cell lymphoma. Despite promising therapeutic outcomes, CAR T cells also can elicit the immune-pathologic effects, such as Cytokine Release Syndrome (CRS), Tumor Lysis Syndrome (TLS), and on-target off-tumor toxicity, that hampered its application. Ineffective control of these highly potent synthetic cells causes discussed potentially life-threatening toxicities, so researchers have developed several mechanisms to remote control CAR T cells. In this paper, we briefly review the introduced toxicities of CAR-T cells, then describe currently existing control approaches and review their procedure, pros, and cons.  相似文献   
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