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881.
Ayan Pradhan Aniruddha Bagchi Soumita De Sneha Mitra Shibabrata Mukherjee Parasar Ghosh 《Free radical research》2019,53(7):768-779
Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disorder wherein the contributory role of oxidative stress has been established in the synovial fluid. As availability of synovial fluid is limited, this study aimed to evaluate in the peripheral blood of patients with RA, the relationship if any, between the extent of oxidative stress in terms of generation of reactive oxygen species (ROS) in neutrophils, plasma NADPH oxidase and myeloperoxidase activity with markers of oxidative damage, circulating cytokines and disease activity score (DAS28). In patients with RA, neutrophils in peripheral blood demonstrated an enhanced generation of ROS, coupled with depletion of free radical scavenging activity. Furthermore, the NADPH oxidase and myeloperoxidase activity was enhanced as were markers of damage. There was a positive correlation between the DAS 28 and generation of ROS, NADPH oxidase and myeloperoxidase activity as also with oxidative stress mediated protein carbonylation. Patients with RA demonstrated an increase in proinflammatory (IL-17, IL-23, and IFN-γ) and some anti-inflammatory (IL-4, IL-5, and TGF-β) cytokines. Although the levels of IL-17 correlated positively with generation of ROS, myeloperoxidase, markers of protein damage and DAS28, IL-23 correlated positively only with protein damage, and negatively with free radical scavenging activity. Importantly, incubation of neutrophils from healthy donors with plasma or SF from patients with RA translated into an enhanced generation of ROS, along with an elevation of intracellular proinflammatory cytokines. Taken together, in patients with RA, circulating neutrophils mediated a shift in the oxidant/antioxidant balance favouring the former, which translated into protein damage and contributed towards disease progression. 相似文献
882.
Swatkoski S Gutierrez P Ginter J Petrov A Dinman JD Edwards N Fenselau C 《Journal of proteome research》2007,6(11):4525-4527
Microwave-accelerated proteolysis using acetic acid has been shown to occur specifically on either or both sides of aspartate residues. This chemical cleavage is applied to the yeast ribosome proteome to evaluate its suitability for incorporation into high-throughput automated workflows. Peptide product mixtures were analyzed using either an HPLC-ESI-LTQ-Orbitrap or an HPLC-MALDI-TOF2. The peptides were readily identified, using MASCOT with a modified enzyme rule, and provided information about 73% of the proteome. Implications are considered of the extended length and the presence of multiple basic residues in these peptides. 相似文献
883.
Gene expression programs of human smooth muscle cells: tissue-specific differentiation and prognostic significance in breast cancers
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Chi JT Rodriguez EH Wang Z Nuyten DS Mukherjee S van de Rijn M van de Vijver MJ Hastie T Brown PO 《PLoS genetics》2007,3(9):1770-1784
Smooth muscle is present in a wide variety of anatomical locations, such as blood vessels, various visceral organs, and hair follicles. Contraction of smooth muscle is central to functions as diverse as peristalsis, urination, respiration, and the maintenance of vascular tone. Despite the varied physiological roles of smooth muscle cells (SMCs), we possess only a limited knowledge of the heterogeneity underlying their functional and anatomic specializations. As a step toward understanding the intrinsic differences between SMCs from different anatomical locations, we used DNA microarrays to profile global gene expression patterns in 36 SMC samples from various tissues after propagation under defined conditions in cell culture. Significant variations were found between the cells isolated from blood vessels, bronchi, and visceral organs. Furthermore, pervasive differences were noted within the visceral organ subgroups that appear to reflect the distinct molecular pathways essential for organogenesis as well as those involved in organ-specific contractile and physiological properties. Finally, we sought to understand how this diversity may contribute to SMC-involving pathology. We found that a gene expression signature of the responses of vascular SMCs to serum exposure is associated with a significantly poorer prognosis in human cancers, potentially linking vascular injury response to tumor progression. 相似文献
884.
Nibedita Mukherjee Samrat Mondol Anish Andheria Uma Ramakrishnan 《Conservation Genetics》2007,8(6):1465-1470
Conservation and management of rare and elusive species requires accurate data on presence or absence. In such cases, molecular
genetics based species identification approaches can prove invaluable, especially in conjuncture with non-invasive DNA sampling.
However, non-invasive sources yield DNA in low concentration that is degraded, which could result in false negatives for species
identification. In this paper, we developed a set of primers for PCR-based species identification of tigers. Our results reveal
high rates (upto 90%) of species identification for both fresh (less than 48 h) and old (between 7 days and 3 months) fecal
samples from the field. Experiments reveal that multiplex PCR (amplifying more than one genomic region) results in an increase
in conclusive species identification (and a consequent decrease in the number of false negatives) from 55% to 89% for old
fecal samples. We demonstrate that this increased success is because we experimentally overcome the problems of low DNA template
quantity (using the multiplex PCR kit, increases species identification from 55% to 72%) and low template DNA quality (two
sets of primers increase the species identification success from 72% to 89%). We recommend that multiplex PCR based methods
be used (in conjuncture with species specific primers) for other rare and elusive species since such methods will potentially
significantly decrease error in species identification. 相似文献
885.
Tisha Joy Henian Cao Graeme Black Rayaz Malik Valentine Charlton-Menys Robert A Hegele Paul N Durrington 《Orphanet journal of rare diseases》2007,2(1):1-10
Hereditary chronic pancreatitis (HCP) is a very rare form of early onset chronic pancreatitis. With the exception of the young age at diagnosis and a slower progression, the clinical course, morphological features and laboratory findings of HCP do not differ from those of patients with alcoholic chronic pancreatitis. As well, diagnostic criteria and treatment of HCP resemble that of chronic pancreatitis of other causes. The clinical presentation is highly variable and includes chronic abdominal pain, impairment of endocrine and exocrine pancreatic function, nausea and vomiting, maldigestion, diabetes, pseudocysts, bile duct and duodenal obstruction, and rarely pancreatic cancer. Fortunately, most patients have a mild disease. Mutations in the PRSS1 gene, encoding cationic trypsinogen, play a causative role in chronic pancreatitis. It has been shown that the PRSS1 mutations increase autocatalytic conversion of trypsinogen to active trypsin, and thus probably cause premature, intrapancreatic trypsinogen activation disturbing the intrapancreatic balance of proteases and their inhibitors. Other genes, such as the anionic trypsinogen (PRSS2), the serine protease inhibitor, Kazal type 1 (SPINK1) and the cystic fibrosis transmembrane conductance regulator (CFTR) have been found to be associated with chronic pancreatitis (idiopathic and hereditary) as well. Genetic testing should only be performed in carefully selected patients by direct DNA sequencing and antenatal diagnosis should not be encouraged. Treatment focuses on enzyme and nutritional supplementation, pain management, pancreatic diabetes, and local organ complications, such as pseudocysts, bile duct or duodenal obstruction. The disease course and prognosis of patients with HCP is unpredictable. Pancreatic cancer risk is elevated. Therefore, HCP patients should strongly avoid environmental risk factors for pancreatic cancer. 相似文献
886.
Background
Recent developments in metabolic engineering and the need for expanded compatibility required for co-expression studies, underscore the importance of developing new plasmid vectors with properties such as stability and compatibility. 相似文献887.
The present study was designed to develop and compare acyclovir containing nano-vesicular liposomes and niosomes based on cholesterol, soya L-alpha-lecithin and nonionic surfactant, span 20. The effort was made to study in vitro whether acyclovir-loaded nanovesicles could sustain the release of the drug by increasing residence time and thus, acyclovir could reduce its dose-related systemic toxicity. There were good vesicular distributions in both of the niosomes and the liposomes. The obtained vesicles were within 1 microm and about 35% of them were within a size of 100 nm. The percentage of drug loading varied and the niosomal vesicles contained more drug as compared with the liposomes. When the in vitro drug release was compared, it was found that the liposomes released about 90% drug in 150 min whereas the drug release was just 50% from the niosomal vesicles in 200 min. Again, the niosomes showed better stability compared with the liposomes. Thus, niosome could be a better choice for intravenous delivery of acyclovir. 相似文献
888.
Priyabrata Mukherjee Resham Bhattacharya Nancy Bone Yean K Lee Chitta Ranjan Patra Shanfeng Wang Lichun Lu Charla Secreto Pataki C Banerjee Michael J Yaszemski Neil E Kay Debabrata Mukhopadhyay 《Journal of nanobiotechnology》2007,5(1):1-13
Background
Neuroblastoma, a frequently occurring solid tumour in children, remains a therapeutic challenge as existing imaging tools are inadequate for proper and accurate diagnosis, resulting in treatment failures. Nanoparticles have recently been introduced to the field of cancer research and promise remarkable improvements in diagnostics, targeting and drug delivery. Among these nanoparticles, quantum dots (QDs) are highly appealing due to their manipulatable surfaces, yielding multifunctional QDs applicable in different biological models. The biocompatibility of these QDs, however, remains questionable. 相似文献889.
Mukherjee A Soyal SM Fernandez-Valdivia R DeMayo FJ Lydon JP 《Genesis (New York, N.Y. : 2000)》2007,45(10):639-646
Through an established gene-targeting strategy, reverse tetracycline-dependent transactivator (rtTA) was targeted downstream of the murine progesterone receptor (PR) promoter. Mice were generated in which one (PR(+/rtTA)) or both (PR(rtTA/rtTA)) PR alleles harbor the rtTA insertion. The PR(+/rtTA) and PR(rtTA/rtTA) knockins exhibit phenotypes identical to the normal and the progesterone receptor knockout mouse, respectively. Crossed with the TZA reporter, which carries the TetO-LacZ responder transgene, the PR(+/rtTA)/TZA and PR(rtTA/rtTA)/TZA bigenics exhibit doxycycline-induced beta-galactosidase activity specifically in progesterone responsive target tissues such as the mammary gland, uterus, ovary, and pituitary gland. In the case of the PR(+/rtTA)/TZA mammary epithelium, dual immunofluorescence demonstrated that PR expression and doxycycline-induced beta-galactosidase activity colocalized; beta-galactosidase was not detected in the absence of doxycycline. Although both the PR(+/rtTA) and PR(rtTA/rtTA) knockins represent innovative animal models with which to further query progesterone's mechanism of action in vivo, the PR(rtTA/rtTA) mouse in particular promises to provide unique insight into the paracrine mechanism of action, which underpins progesterone's involvement in mammary morphogenesis with obvious implications for extending our understanding of this steroid's role in breast cancer progression. 相似文献
890.
Sterol, protein and lipid trafficking in Chinese hamster ovary cells with Niemann-Pick type C1 defect 总被引:2,自引:0,他引:2
We studied the trafficking of sterols, lipids and proteins in Niemann-Pick type C (NPC) cells. The NPC is an inherited disorder involving the accumulation of sterol and lipids in modified late-endosome/lysosome-like storage organelles. Most sterol accumulation studies in NPC cells have been carried out using low-density lipoprotein (LDL) as the sterol source, and it has been shown that sterol efflux from late endosomes is impaired in NPC cells. In this study, we used a fluorescent sterol analog, dehydroergosterol, which can be quickly and efficiently delivered to the plasma membrane. Thus, we were able to study the trafficking kinetics of the non-LDL-derived sterol pool, and we found that dehydroergosterol accumulates in the storage organelles over the course of several hours in NPC cells. We also found that dialkylindocarbocyanine lipid-mimetic analogs that recycle efficiently from early endosomes in wild-type cells are targeted to late endosomal organelles in NPC cells, and transferrin receptors recycle slowly and inefficiently in NPC cells. These data are consistent with multiple trafficking defects in both early and late endosomes in NPC cells. 相似文献