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排序方式: 共有262条查询结果,搜索用时 31 毫秒
251.
Over the globe, the incidence of glioblastoma multiforme (GM) is very low, that is, 1–4 cases per 100,000, but it is fatal and cancer grows very fast inside the brain tissues, namely astrocytes and oligodendrocytes. Because of the rapid growth, it is difficult to halt the dissemination of tumor in adjacent tissues. Although temozolomide (TMZ) is a currently approved standard of care, it develops resistance over the period. Therefore, there is a need to develop a novel drug delivery system. In this work, authors have developed platelets as drug delivery carriers-loaded with quercetin (QCT) for targeting GM. The effect of QCT and QCT-platelet was assessed on the U373-MG cell line. Natural human platelets were used as carriers for drug loading and drug delivery. Platelets possess an open canalicular system that allows the uptake of drug molecules in the platelet cytoplasm. The study showed that the maximum encapsulation efficiency of QCT-platelet was 93.96 ± 0.12% and the maximum drug release in 24 h was 76.26 ± 0.13% in-vitro at pH 5.5 that mimics the tumor microenvironment. In this work, there is a three-fold enhancement of solubility of QCT. The cytotoxic activity of QCT-platelets was studied in the U373-MG human astrocytoma glioblastoma cell line and the cell viability was 14.52 ± 1.53% after 48 h. Thus, platelets were proved as good carriers for therapeutic moieties and can be effectively used to target the glioblastoma tumor in the near future. 相似文献
252.
Gold nanoclusters (AuNCs) are potential carrier system for bioactive like proteins and peptides used in various therapeutics against various ailments. Neuropeptide Y (NPY) is consists of 36 amino acids used to treat depression, obesity, epilepsy, and so on. but possess instability at higher temperatures causing its limited usage. The present study focused on the NPY-decorated AuNCs prepared using desolvation reduction technique and optimized through randomized hybrid design. ATR-FTIR, 1H NMR and CD spectroscopic studies confirmed the AuNCs structure interaction with NPY. The optimized NPY-decorated AuNCs possessed 85.6 ± 2.08% of entrapment efficiency with 85.32 ± 7.55% of NPY release for 24 h. It displayed dose-dependent cell cytotoxicity, IC50 value of 0.7 ± 0.05 μg mL-1 and apoptosis of 68.48 ± 7.35% with controlled cell migration causing G0G1 cell arrest by penetrating cancer cell membrane on MCF-7 cell line. Furthermore, the AuNCs caused surface disruption of the cancerous cell further interrupting the protein synthesis by MAPK pathway leading to cell death. The AuNCs were stable for 3 months at 25 ± 2°C due to steric hindrance. Hence, NPY-decorated AuNCs were found to be effective on MCF-7 cell line with a significant anti-apoptotic effect, further emerging as a novel therapeutic delivery system in the management of breast cancer. 相似文献
253.
Tumor microenvironment (TME) comprising cellular and non-cellular components is a major source of cancer hallmarks. Notably, angiogenesis responsible for normal physiological remodeling process can otherwise harness vessel abnormalities during tumorigenesis eliciting severe therapeutic inefficiency. Currently, FDA approved antiangiogenic drugs have only shown modest clinical success owing to tumor hypoxia, antiangiogenic therapeutic resistance, and limited knowledge in understanding TME. In order to overcome these limitations, targeting angiogenesis combined with immunosuppressive TME could offer potential therapeutic opportunities. Indeed, these therapeutic approaches can be further revisited with the advent of nanotechnology that can target the key cellular components of TME and tumor cells more precisely. Synergetic targeting without eliciting systemic toxicity achieved by integration of antiangiogenic and immunotherapy in a single nanoplatform is vital for therapeutic success. In this review, we will discuss the most promising nanotechnological advancements oriented to modulate the immunosuppressive TME in association with antiangiogenic therapy that has gained immense popularity in cancer treatment. 相似文献
254.
Badgujar Vivek C. Badgujar Kirtikumar C. Yeole Pravin M. Bhanage Bhalchandra M. 《Bioprocess and biosystems engineering》2017,40(10):1463-1478
Bioprocess and Biosystems Engineering - The present work deals with the designing of biocompatible hybrid blend of cellulosic copolymers made of hydroxypropyl methylcellulose (HMC) and chitosan... 相似文献
255.
256.
Pravin T. P. Kaumaya Susan Kobs-Conrad Young Hoon Seo Hyosil Lee Anne M. Vanbuskirk Ningguo Feng John F. Sheridan Vernon Stevens 《Journal of molecular recognition : JMR》1993,6(2):81-94
An ideal peptide vaccine should contain both B- and T-cell epitopes. Recognition of antigen by B cells is highly dependent on the three-dimensional conformation of the antigen whereas T cells recognize antigen only after it has been processed to release a peptide fragment which is bound to the major histocompatibility complex (MHC) class II molecule. However, T cells provide ‘help’ to B cells displaying the same processed, MHC-restricted from of the antigen, demonstrating that the T-cell response to a protein antigen is under genetic control. Thus, strategies for co-inclusion of T cell ‘helper’ epitopes with the B-cell determinant elicit immune responses that are in most cases genetically restricted to only one or a few alleles of the MHC with limited activity across divergent MHC class II haplotypes. This genetically restricted T cell stimulatory activity of peptides is a serious obstacle and consequently such constructs would be of limited practical value as a vaccine targeted to a majority of an outbred population. In the study described here, we have engineered tow peptides to encompass the sequences from the universally immunogenic tetanus toxoid (TT) epitope and the contraceptive vaccine candidate lactate dehydrogenase C4 (LDH-C4). We demonstrate the feasibility of using ‘promiscuous’ T-Cell epitopes colinearly constructed with a defined B-cell epitope to induce high titer antipeptide IgG antibodies specific for native protein antigen LDH-C4 in several inbred strains of mice, outbred mice and rabbits. There appears to be a strong correlation between the capacity for the hybrid peptides to be stimulatory for the corresponding T cells in C57BL/6 (H-2b) and C3H/HeJ (H-2k) mice and their ability to be immunogenic. This correlation, however, appears to break down in H-2d strains of mice since no antibodies were detected in BALB/c and barely detectable levels of antibodies in B10.D2 although activated T cells were detectable. Conversely, high titers of antipeptide antibodies are elicited in some strains (B10.BR) (H-2k); C57BL/10 (H-2k) without detectable IL-2 responses. Finally, we show that a determinant which was previously restricted to H-2k can be rendered immunogenic in H-2b with the ‘promiscuous’ TT epitope. Thus, certain haplotype-restricted immune responses can be bypassed, setting forth the ground work for the design of a universal vaccine by broadening the effective response in a larger number of individuals typically of the genetically diverse outbred human population. 相似文献
257.
Badgujar Vivek C. Badgujar Kirtikumar C. Yeole Pravin M. Bhanage Bhalchandra M. 《Bioprocess and biosystems engineering》2019,42(1):47-61
Bioprocess and Biosystems Engineering - The present work reports covalent immobilization of steapsin lipase (SL) on Immobead-350 support matrix (IMB) to make a robust biocatalytic system to work... 相似文献
258.
Reduced Pancreatic Exocrine Function and Organellar Disarray in a Canine Model of Acute Pancreatitis
Yuepeng Jin Yongyu Bai Qiang Li Pravin Avinash Bhugul Xince Huang Lewei Liu Liangliang Pan Haizhen Ni Bicheng Chen Hongwei Sun Qiyu Zhang Michael Hehir Mengtao Zhou 《PloS one》2016,11(2)
The aim of the present study was to investigate the pancreatic exocrine function in a canine model and to analyze the changes in organelles of pancreatic acinar cells during the early stage of acute pancreatitis (AP). AP was induced by retrograde injection of 5% sodium taurocholate (0.5 ml/kg) into the main pancreatic duct of dogs. The induction of AP resulted in serum hyperamylasemia and a marked reduction of amylase activity in the pancreatic fluid (PF). The pancreatic exocrine function was markedly decreased in subjects with AP compared with the control group. After the induction of AP, histological examination showed acinar cell edema, cytoplasmic vacuolization, fibroblasts infiltration, and inflammatory cell infiltration in the interstitium. Electron micrographs after the induction of AP revealed that most of the rough endoplasmic reticulum (RER) were dilated and that some of the ribosomes were no longer located on the RER. The mitochondria were swollen, with shortened and broken cristae. The present study demonstrated, in a canine model, a reduced volume of PF secretion with decreased enzyme secretion during the early stage of AP. Injury of mitochondria and dilatation and degranulation of RER may be responsible for the reduced exocrine function in AP. Furthermore, the present model and results may be useful for researching novel therapeutic measures in AP. 相似文献
259.
Pravin B. Sehgal Huijuan Yuan Mia F. Scott Yan Deng Feng-Xia Liang Andrzej Mackiewicz 《The Journal of biological chemistry》2020,295(52):18023
Type I and III interferons induce expression of the “myxovirus resistance proteins” MxA in human cells and its ortholog Mx1 in murine cells. Human MxA forms cytoplasmic structures, whereas murine Mx1 forms nuclear bodies. Whereas both HuMxA and MuMx1 are antiviral toward influenza A virus (FLUAV) (an orthomyxovirus), only HuMxA is considered antiviral toward vesicular stomatitis virus (VSV) (a rhabdovirus). We previously reported that the cytoplasmic human GFP-MxA structures were phase-separated membraneless organelles (“biomolecular condensates”). In the present study, we investigated whether nuclear murine Mx1 structures might also represent phase-separated biomolecular condensates. The transient expression of murine GFP-Mx1 in human Huh7 hepatoma, human Mich-2H6 melanoma, and murine NIH 3T3 cells led to the appearance of Mx1 nuclear bodies. These GFP-MuMx1 nuclear bodies were rapidly disassembled by exposing cells to 1,6-hexanediol (5%, w/v), or to hypotonic buffer (40–50 mosm), consistent with properties of membraneless phase-separated condensates. Fluorescence recovery after photobleaching (FRAP) assays revealed that the GFP-MuMx1 nuclear bodies upon photobleaching showed a slow partial recovery (mobile fraction: ∼18%) suggestive of a gel-like consistency. Surprisingly, expression of GFP-MuMx1 in Huh7 cells also led to the appearance of GFP-MuMx1 in 20–30% of transfected cells in a novel cytoplasmic giantin-based intermediate filament meshwork and in cytoplasmic bodies. Remarkably, Huh7 cells with cytoplasmic murine GFP-MuMx1 filaments, but not those with only nuclear bodies, showed antiviral activity toward VSV. Thus, GFP-MuMx1 nuclear bodies comprised phase-separated condensates. Unexpectedly, GFP-MuMx1 in Huh7 cells also associated with cytoplasmic giantin-based intermediate filaments, and such cells showed antiviral activity toward VSV. 相似文献
260.
AbstractIn the present study, Isoptericola variabilis strain UD-6 isolated from alkaline hot spring of Unapdev, Maharashtra, India was assessed for its biobleaching activity by hydrolytic enzymes on rice straw pulp. Results of primary and secondary screening manifested that it was a multi-enzyme producer, competent to produce amylase, cellulase, mannanase, pectinase, and xylanase at 9.73, 4.11, 6.26, 8.42, and 6.61?IU?ml?1 in fermentation conditions, respectively. Maximum activity of all enzymes was gained at thermal temperature (50–55?°C), alkaline condition (pH 8–9), under 5?mM KCl and 5?mM NaCl salt concentration. In compatibility testing, activities of all enzymes were spectacularly reduced when they utilized with chemicals of pulp bleaching. Results of rice straw pulp bleaching was effectual when pulp was initially bleached with mannanase, pectinase, and xylanase enzymes (Es) for 90?min and then with diluted chemicals (DC) for further 90?min instead of their separate use. Treatment of rice straw pulp with Es?+?DC, enhanced the release of reducing sugars, hydrophobic compounds, and phenolic compounds, whereas Kappa number was reduced. Overall, the results of the present study indicated that pre-bleaching of pulp with hydrolytic enzymes obtained from I. variabilis strain UD-6 helps to minimize chemicals used in the bleaching process and make it more sustainable for pulp and paper industries as well as for the environment. 相似文献