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排序方式: 共有254条查询结果,搜索用时 15 毫秒
1.
Dasgupta S Bhattacharya-Chatterjee M O'Malley BW Chatterjee SK 《Journal of cellular biochemistry》2006,97(5):1036-1051
In an orthotopic murine model of head and neck cancer, combined subcutaneous and intratumoral vaccination with recombinant vaccinia virus expressing interleukin-2 (rvv-IL-2) induced significant tumor regression early on therapy. However, its efficacy was restricted by recurrent tumor growth and loco-regional metastases. In this study, we explored the mechanism of tumor metastasis. We compared the levels of expression of a number of molecules involved in tumor metastasis, which included transforming growth factor-beta1 (TGF-beta1), E-cadherin, matrix metalloproteinases (MMPs): MT1-MMP, MMP-2, MMP-9, their tissue inhibitors (TIMPs): TIMP-1/TIMP-2, and pro-angiogenic factors CD31, VEGF-R2, and iNOS between primary and metastatic tumors by real-time RT-PCR and immunohistochemistry. We detected spontaneous lymph node and tongue metastasis. Metastasis was delayed in rvv-IL-2 treated mice. Cultured tumor cells expressed negligible amount of TGF-beta1. Untreated or metastatic tumors, on the other hand, expressed high levels of TGF-beta1 and secreted TGF-beta1 in the sera of tumor-bearing mice. Levels of TGF-beta1 in the sera suddenly jumped at the time when tumor metastasis started. In the metastatic tumors, levels of MT1-MMP, MMP-2, and MMP-9 were significantly elevated (P < 0.001), while levels of TIMP-1/TIMP-2 and E-cadherin were decreased (P < 0.001) compared to control or primary tumors. Levels of CD31, VEGF-R2, and iNOS were also significantly elevated in the metastatic lesions (P < 0.001). The concurrence of high levels of TGF-beta1 in the sera, expression of proteins involved in metastasis and initiation of metastasis suggested possible role of TGF-beta1 in on setting the metastatic cascade in this model. 相似文献
2.
Hadj S. Aoued Soma Sannigrahi Sarah C. Hunter Nandini Doshi Zakia S. Sathi Anthony W. S. Chan Hasse Walum Brian G. Dias 《Genes, Brain & Behavior》2020,19(4)
Salient sensory environments experienced by a parental generation can exert intergenerational influences on offspring. While these data provide an exciting new perspective on biological inheritance, questions remain about causes and consequences of intergenerational influences of salient sensory experience. We previously showed that exposing male mice to a salient olfactory experience, like olfactory fear conditioning, resulted in offspring demonstrating a sensitivity to the odor used to condition the paternal generation and possessing enhanced neuroanatomical representation for that odor. In this study, we first injected RNA extracted from sperm of male mice that underwent olfactory fear conditioning into naïve single‐cell zygotes and found that adults that developed from these embryos had increased sensitivity and enhanced neuroanatomical representation for the odor (Odor A) with which the paternal male had been conditioned. Next, we found that female, but not male offspring sired by males conditioned with Odor A show enhanced consolidation of a weak single‐trial Odor A + shock fear conditioning protocol. Our data provide evidence that RNA found in the paternal germline after exposure to salient sensory experiences can contribute to intergenerational influences of such experiences, and that such intergenerational influences confer an element of adaptation to the offspring. In so doing, our study of intergenerational influences of parental sensory experience adds to existing literature on intergenerational influences of parental exposures to stress and dietary manipulations and suggests that some causes (sperm RNA) and consequences (behavioral flexibility) of intergenerational influences of parental experiences may be conserved across a variety of parental experiences. 相似文献
3.
Shrivastava Vineeta Savarimuthu Arockiasamy Patil Manoj Sarkar Purbasha Hadole Sainath Dasgupta Santanu 《Plant Cell, Tissue and Organ Culture》2021,144(2):359-370
Plant Cell, Tissue and Organ Culture (PCTOC) - Jatropha curcas is an undomesticated crop and its plantations did not meet commercial expectation due to absence of high yielding commercial line with... 相似文献
4.
Sarkar Monaj Kumar Kar Amrita Jayaraman Adithyan Shanmugam Karthi Vadivel Vellingiri Mahapatra Santanu Kar 《Molecular biology reports》2021,48(6):5327-5334
Molecular Biology Reports - Myricitrin, a naturally occurring flavonoid in Madhuca longifolia, possesses several medicinal properties. Even though our earlier work revealed its role against the... 相似文献
5.
Sahabuddin Sarwardi Prashanta Kumar Mandal Santanu Ray 《Journal of biological physics》2013,39(4):701-722
A three-component model consisting on one-prey and two-predator populations is considered with a Holling type II response function incorporating a constant proportion of prey refuge. We also consider the competition among predators for their food (prey) and shelter. The essential mathematical features of the model have been analyzed thoroughly in terms of stability and bifurcations arising in some selected situations. Threshold values for some parameters indicating the feasibility and stability conditions of some equilibria are determined. The range of significant parameters under which the system admits different types of bifurcations is investigated. Numerical illustrations are performed in order to validate the applicability of the model under consideration. 相似文献
6.
Pal S Ghosh S Mandal C Kohla G Brossmer R Isecke R Merling A Schauer R Schwartz-Albiez R Bhattacharya DK Mandal C 《Glycobiology》2004,14(10):859-870
Sialic acids as terminal residues of oligosaccharide chains play crucial roles in several cellular recognition events. Exploiting the selective affinity of Achatinin-H toward N-acetyl-9-O-acetylneuraminic acid-alpha2-6-GalNAc, we have demonstrated the presence of 9-O-acetylated sialoglycoproteins (Neu5,9Ac(2)-GPs) on lymphoblasts of 70 children with acute lymphoblastic leukemia (ALL) and on leukemic cell lines by fluorimetric HPLC and flow cytometric analysis. This study aims to assess the structural aspect of the glycotope of Neu5,9Ac(2)-GPs(ALL) and to evaluate whether these disease-specific molecules can be used to monitor the clinical outcome of ALL. The Neu5,9Ac(2)-GPs(ALL) were affinity-purified, and three distinct leukemia-specific molecular determinants (135, 120, and 90 kDa) were demonstrated by SDS-PAGE, western blotting, and isoelectric focusing. The carbohydrate epitope of Neu5,9Ac(2)-GPs(ALL) was confirmed by using synthetic sialic acid analogs. The enhanced presence of anti-Neu5,9Ac(2)-GP(ALL) antibody in ALL patients prompted us to develop an antigen-ELISA using purified Neu5,9Ac(2)-GPs(ALL) as coating antigens. Purified antigen was able to detect leukemia-specific antibodies at presentation of disease, which gradually decreased with treatment. Longitudinal monitoring of 18 patients revealed that in the early phase of the treatment patients with lower anti-Neu5,9Ac(2)-GPs showed a better prognosis. Minimal cross-reactivity was observed in other hematological disorders (n = 50) like chronic myeloid leukemia, acute myelogenous leukemia, chronic lymphocytic leukemia, and non-Hodgkin's lymphoma as well as normal healthy individuals (n = 21). This study demonstrated the potential of purified Neu5,9Ac(2)-GPs(ALL) as an alternate tool for detection of anti-Neu5,9Ac(2)-GP antibodies to be helpful for diagnosis and monitoring of childhood ALL patients. 相似文献
7.
Co-ordinated expression of multiple enzymes in different subcellular compartments in plants 总被引:4,自引:0,他引:4
Santanu Dasgupta Glenn B. Collins Arthur G. Hunt 《The Plant journal : for cell and molecular biology》1998,16(1):107-116
A gene expression system designed for coordinated expression of multiple genes in plants and their targeting to specified subcellular locations was tested. A series of genes encoding polyproteins containing the tobacco vein mottling virus (TVMV) NIa proteinase along with two other reporter genes (those encoding the Escherichia coli acetate kinase (ACK) and Tn9 chloramphenicol acetyl transferase (CAT) enzymes) were assembled. The respective coding sequences of these genes were separated by a TVMV NIa proteinase recognition sequence. In addition, in some instances, chloroplast targeting information (a transit peptide (TP) from a pea rbcS gene) was incorporated into the polyprotein. We found that the NIa proteinase can be used to express, as individual polypeptides, the ACK and CAT proteins, and that these proteins retain enzymatic activity. Polyproteins with the structure TP-NIa-ACK-CAT or TP-ACK-CAT-NIa failed to yield chloroplast-localized ACK and CAT proteins, although the latter did give rise to a chloroplast-localized ACK-CAT polyprotein. These results indicate that the NIa proteinase acts in cis more rapidly than transport of proteins into the chloroplast, but that chloroplast localization can take place before complete processing of the polyprotein. Polyproteins with the structures ACK-NIa-TP-CAT and TP-ACK-NIa-TP-CAT yielded appropriately processed and targeted ACK and CAT. Our results show that subcellular localization signals can be effectively recognized in the context of a polyprotein, and they suggest an appropriate strategy for simultaneous engineering of multiple subcellular compartments in plants. 相似文献
8.
Stefan Clerens Charisa D. Cornellison Santanu Deb-Choudhury Ancy Thomas Jeffrey E. Plowman Jolon M. Dyer 《Journal of Proteomics》2010,73(9):1722-1731
The wool proteome has been largely uncharted due to a lack of database coverage, poor protein extractability and dynamic range issues. Yet, investigating correlations between wool physical properties and protein content, or characterising UV-, heat- or processing-induced protein damage requires the availability of an identifiable and identified proteome.In this study we have achieved unprecedented wool proteome identification through a strategy of comprehensive data acquisition, iterative protein identification/validation and concurrent augmentation of the sequence database. Data acquisition comprised a range of different hyphenated MS techniques including LC–MS/MS, LC–MALDI, 2D-LC–MS/MS and SDS-PAGE LC–MS. Using iterative searching of databases and search result combination using ProteinScape, a systematic expansion of identifiable proteins in the sequence database was achieved. This was followed by extensive validation and rationalisation of the protein identifications. In total, 72 complete and 30 partial ovine-specific protein sequences were added to the database, and 113 wool proteins were identified.Enhanced access to ovine-specific protein identification and characterisation will facilitate all wool fibre protein chemistry and proteomics research. 相似文献
9.
Background
In farm animals, there is no suitable cell line available to understand liver-specific functions. This has limited our understanding of liver function and metabolism in farm animals. Culturing and maintenance of functionally active hepatocytes is difficult, since they survive no more than few days. Establishing primary culture of hepatocytes can help in studying cellular metabolism, drug toxicity, hepatocyte specific gene function and regulation. Here we provide a simple in vitro method for isolation and short-term culture of functionally active buffalo hepatocytes.Results
Buffalo hepatocytes were isolated from caudate lobes by using manual enzymatic perfusion and mechanical disruption of liver tissue. Hepatocyte yield was (5.3±0.66)×107 cells per gram of liver tissue with a viability of 82.3±3.5%. Freshly isolated hepatocytes were spherical with well contrasted border. After 24 hours of seeding onto fibroblast feeder layer and different extracellular matrices like dry collagen, matrigel and sandwich collagen coated plates, hepatocytes formed confluent monolayer with frequent clusters. Cultured hepatocytes exhibited typical cuboidal and polygonal shape with restored cellular polarity. Cells expressed hepatocyte-specific marker genes or proteins like albumin, hepatocyte nuclear factor 4α, glucose-6-phosphatase, tyrosine aminotransferase, cytochromes, cytokeratin and α1-antitrypsin. Hepatocytes could be immunostained with anti-cytokeratins, anti-albumin and anti α1-antitrypsin antibodies. Abundant lipid droplets were detected in the cytosol of hepatocytes using oil red stain. In vitro cultured hepatocytes could be grown for five days and maintained for up to nine days on buffalo skin fibroblast feeder layer. Cultured hepatocytes were viable for functional studies.Conclusion
We developed a convenient and cost effective technique for hepatocytes isolation for short-term culture that exhibited morphological and functional characteristics of active hepatocytes for studying gene expression, regulation, hepatic genomics and proteomics in farm animals. 相似文献10.
Lauren?D.?Quinn Kaitlin?C.?Straker Jia?Guo S.?Kim Santanu?Thapa Gary?Kling D.?K.?Lee Thomas?B.?VoigtEmail author 《Bioenergy Research》2015,8(3):1081-1100
Given the mandated increases in fuel production from alternative sources, limited high-quality production land, and predicted climate changes, identification of stress-tolerant biomass crops will be increasingly important. However, existing literature largely focuses on the responses of a small number of crops to a single source of abiotic stress. Here, we provide a much-needed review of several types of stress likely to be encountered by biomass crops on marginal lands and under future climate scenarios: drought, flooding, salinity, cold, and heat. The stress responses of 17 leading biomass crops of all growth habits (e.g., perennial grasses, short-rotation woody crops, and large trees) are summarized, and we identify several that could be considered “all purpose” for multiple stress types. Importantly, we note that some of these crops are or could become invasive in some landscapes. Therefore, growers must take care to avoid dissemination of plants or propagules outside of cultivation. 相似文献