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排序方式: 共有235条查询结果,搜索用时 15 毫秒
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MK McKenna BW Gachuki SS Alhakeem KN Oben VM Rangnekar RC Gupta S Bondada 《Cancer biology & therapy》2015,16(7):1088-1098
Withaferin A (WA), a withanolide from the plant, Ashwagandha (Withania somnifera) used in Ayurvedic medicine, has been found to be valuable in the treatment of several medical ailments. WA has been found to have anticancer activity against various solid tumors, but its effects on hematological malignancies have not been studied in detail. WA strongly inhibited the survival of several human and murine B cell lymphoma cell lines. Additionally, in vivo studies with syngeneic-graft lymphoma cells suggest that WA inhibits the growth of tumor but does not affect other proliferative tissues. We demonstrate that WA inhibits the efficiency of NF-κB nuclear translocation in diffuse large B cell lymphomas and found that WA treatment resulted in a significant decrease in protein levels involved in B cell receptor signaling and cell cycle regulation. WA inhibited the activity of heat shock protein (Hsp) 90 as reflected by a sharp increase in Hsp70 expression levels. Hence, we propose that the anti-cancer effects of WA in lymphomas are likely due to its ability to inhibit Hsp90 function and subsequent reduction of critical kinases and cell cycle regulators that are clients of Hsp90. 相似文献
104.
Photosynthetic electron transport in genetically altered photosystem II reaction centers of chloroplasts.
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R A Roffey J H Golbeck C R Hille R T Sayre 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(20):9122-9126
Using a cotransformation system to identify chloroplast transformants in Chlamydomonas reinhardtii, we converted histidine-195 of the photosystem II reaction center D1 protein to a tyrosine residue. The mutants were characterized by a reduced quantum efficiency for photosynthetic oxygen evolution, which varied in a pH-dependent manner, a reduced capacity to oxidize artificial donors to photosystem II, and P680+ reduction kinetics (microsecond) that were essentially similar to wild type. In addition, a dark-stable radical was detected by ESR in mutant photosystem II particles but not in wild-type particles. This radical was similar in g value and lineshape to chlorophyll or carotenoid cations but could have arisen from a tyrosine-195 cation. The ability of the photosystem II trap (P680+) to oxidize tyrosine residues suggests that the mutant tyrosine residue could be used as a redox-sensitive probe to investigate the environment around the photosystem II trap. 相似文献
105.
Transplantation of enriched and purged peripheral blood progenitor cells from a single apheresis product in patients with non-Hodgkin's lymphoma 总被引:1,自引:2,他引:1
Negrin RS; Kusnierz-Glaz CR; Still BJ; Schriber JR; Chao NJ; Long GD; Hoyle C; Hu WW; Horning SJ; Brown BW 《Blood》1995,85(11):3334-3341
High-dose chemotherapy with or without radiotherapy followed by autologous transplantation of hematopoietic progenitor cells is an effective treatment for patients with high-risk or relapsed non- Hodgkin's lymphoma. Chemotherapy and/or hematopoietic growth factors have been used to mobilize progenitor cells in the peripheral blood for transplantation. However, the mobilized blood cell products have been found to be frequently contaminated with tumor cells, and techniques have not been developed to purge tumor cells from these products. In addition, the minimum number of hematopoietic progenitor cells required for engraftment has not yet been fully elucidated. We treated 21 patients with a single infusion of cyclophosphamide (4 g/m2) followed by daily administration of granulocyte colony-stimulating factor (G- CSF). After recovery of the white blood cell count, a single 3-hour apheresis collection was performed. The apheresis product was then applied to a discontinuous Percoll gradient. The low-density fractions resulting from this separation procedure were enriched for CD34+ progenitor cells (total cell yield, 19.5%; CD34+ cell recovery, 81.2%). These enriched cellular products were treated with a panel of anti-B cell or anti-T cell monoclonal antibodies and complement in an effort to remove residual tumor cells. After treatment of the patient with myeloablative therapies, the enriched and purged cells were reinfused. Hematologic recovery was rapid, with median neutrophil engraftment in 10 days [absolute neutrophil count (ANC), greater than 0.5 x 10(9)/L] and 11 days (ANC, greater than 1.0 x 10(9)/L). Median platelet transfusion independence required 13 days. The rapidity of multilineage engraftment correlated with the number of CD34+ cells per kilogram that were infused. Patients who received more than 2 x 10(6) CD34+ cells per kilogram had rapid hematologic engraftment, whereas those patients transplanted with less than 2 x 10(6) CD34+ cells per kilogram had slower platelet recovery. Modeling studies using a lymphoma cell line with a t(14; 18) chromosomal translocation demonstrated the successful removal of tumor cells assayed using the polymerase chain reaction (PCR) after the processing and purging. Four of the 21 patients had PCR- detectable lymphoma cells in the bone marrow and peripheral blood; however, the enriched and purged blood products reinfused in all four did not contain detectable tumor cells.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
106.
In humans with B-cell malignancies, the presence of monoclonal B lymphocytes (clonal proliferation) can be detected by comparing the fluorescence intensity distributions of lymphocytes stained with anti- kappa and anti-lambda reagents. The sensitivity of previously described single-color immunofluorescence techniques to low levels of clonal excess is limited by background from cytophilic immunoglobulins on non- B cells and by the low proportion of circulating B cells in individuals with minimal disease. We have used two-color immunofluorescence and B- cell gating to develop an improved assay that avoids false positives due to non-B cells, without requiring restrictive light scatter gates that may exclude true positives. This method is sensitive to 0.2% monoclonal B cells admixed with fresh normal lymphocytes, to 0.6% monoclonal B cells admixed with normal lymphocytes that have been stored for up to 72 hours, and readily detects 1% monoclonal cells in patient specimens. The two color B-cell gated assay offers sensitivity equivalent to the single-color assay and improved specificity for detection of low levels of clonal excess. 相似文献
107.
108.
Mohammad Al-Mahdi Al-Karagholi Hashmat Ghanizada Cherie Amalie Waldorff Nielsen Assan Ansari Christian Gram Samaria Younis Mark B Vestergaard Henrik BW Larsson Lene Theil Skovgaard Faisal Mohammad Amin Messoud Ashina 《Journal of cerebral blood flow and metabolism》2021,41(6):1328
Glibenclamide inhibits sulfonylurea receptor (SUR), which regulates several ion channels including SUR1-transient receptor potential melastatin 4 (SUR1-TRPM4) channel and ATP-sensitive potassium (KATP) channel. Stroke upregulates SURl-TRPM4 channel, which causes a rapid edema formation and brain swelling. Glibenclamide may antagonize the formation of cerebral edema during stroke. Preclinical studies showed that glibenclamide inhibits KATP channel-induced vasodilation without altering the basal vascular tone. The in vivo human cerebrovascular effects of glibenclamide have not previously been investigated.In a randomized, double-blind, placebo-controlled, three-way cross-over study, we used advanced 3 T MRI methods to investigate the effects of glibenclamide and KATP channel opener levcromakalim on mean global cerebral blood flow (CBF) and intra- and extracranial artery circumferences in 15 healthy volunteers. Glibenclamide administration did not alter the mean global CBF and the basal vascular tone. Following levcromakalim infusion, we observed a 14% increase of the mean global CBF and an 8% increase of middle cerebral artery (MCA) circumference, and glibenclamide did not attenuate levcromakalim-induced vascular changes. Collectively, the findings demonstrate the vital role of KATP channels in cerebrovascular hemodynamic and indicate that glibenclamide does not inhibit the protective effects of KATP channel activation during hypoxia and ischemia-induced brain injury. 相似文献
109.
Janet BW Williams Amy Ellis Arthur Middleton Kenneth A Kobak 《Annals of general psychiatry》2007,6(1):24
Background
While primary care physicians play a pivotal role in the treatment of depression, collaboration between primary care and psychiatry in clinical research has been limited. Primary care settings provide unique opportunities to improve the methodology of psychiatric clinical trials, by providing more generalizable and less treatment-resistant patients. We examined the feasibility of identifying, recruiting, screening and assessing primary care patients for psychiatric clinical trials using high-quality videoconferencing in a mock clinical trial. 相似文献110.