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51.
Gamsizkan M Demiriz M Karslioğlu Y Günhan O 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2007,29(3):153-158
OBJECTIVE: Early stage mycosis fungoides (MF) may be indistinguishable from some inflammatory dermatoses (IDs) histopathologically. Various morphologic features of lymphocytes in epidermis and dermis may help to differentiate early-stage MF from other IDs. STUDY DESIGN: We studied 25 cases of early-stage MF and 30 cases of various IDs with prominent exocytosis. The following nuclear variables were measured on dermal and epidermal lymphocytes in MF and IDs (control) groups: nuclear area and perimeter, area convex hull, perimeter convex hull, diameter equivalent circle, minimum feret, maximum feret and form factor. All measurements were done using routinely prepared and hematoxylin-eosin-stained slides. RESULTS: There were statistically significant differences (p < 0.01) for all of the morphometric variables between early-stage MF and IDs. CONCLUSION: Our results revealed that the nuclear contour irregularities of intraepidermal lymphocytes are higher than those of dermal lymphocytes in MF. Their nuclear geometry is also different. Comparison of the nuclear features of intraepidermal with dermal lymphocytes may provide additional support in the diagnosis of early-stage MF. 相似文献
52.
Synchronization of cell death in a dinoflagellate population is mediated by an excreted thiol protease 总被引:3,自引:0,他引:3
Vardi A Eisenstadt D Murik O Berman-Frank I Zohary T Levine A Kaplan A 《Environmental microbiology》2007,9(2):360-369
Regulated programmed cell death (PCD) processes have been documented in several phytoplankton species and are hypothesized to play a role in population dynamics. However, the mechanisms leading to the coordinated collapse of phytoplankton blooms are poorly understood. We showed that the collapse of the annual bloom of Peridinium gatunense, an abundant dinoflagellate in Lake Kinneret, Israel, is initiated by CO2 limitation followed by oxidative stress that triggers a PCD-like cascade. We provide evidences that a protease excreted by senescing P. gatunense cells sensitizes younger cells to oxidative stress and may consequently trigger synchronized cell death of the population. Ageing of the P. gatunense cultures was characterized by a remarkable rise in DNA fragmentation and enhanced sensitivity to H2O2. Exposure of logarithmic phase (young) cultures to conditioning media from stationary phase (old) cells sensitized them to H2O2 and led to premature massive cell death. We detected the induction of specific extracellular protease activity, leupeptin-sensitive, in ageing cultures and in lake waters during the succession of the P. gatunense bloom. Partial purification of the conditioned media revealed that this protease activity is responsible for the higher susceptibility of young cells to oxidative stress. Inhibition of the protease activity lowered the sensitivity to oxidative stress, whereas application of papain to logarithmic phase P. gatunense cultures mimicked the effect of the spent media and enhanced cell death. We propose a novel mechanistic framework by which a population of unicellular phytoplankton orchestrates a coordinated response to stress, thereby determine the fate of its individuals. 相似文献
53.
A combination of gene expression ranking and co‐expression network analysis increases discovery rate in large‐scale mutant screens for novel Arabidopsis thaliana abiotic stress genes
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54.
In this study, effects of different starches (tapioca (TS), wheat (WS), corn (CS), potato (PS), modified corn (MCS) and modified
potato (MPS)) and gums (xanthan gum (XG), guar gum (GG), alginate (A), salep (S), locust bean gum (LBG) and carrageen (C))
on the rheological properties of model hot chocolate beverage were studied. Swelling power (SP) of the starches and water
absorption capacity (WAC) of the gums were determined. Hot chocolate beverages showed pseudoplastic behaviour. Ostwald de
Waele model accurately described flow behaviour of each beverage sample. K, n, R
2 values for Ostwald model were in the range of 4.8–160.3 mPa.sn, 0.5117–0.9745, 0.9972–0.9998, respectively. The highest synergic effect in the model was observed between the interaction
of MCS and XG. The XG-PS, XG-TS, XG-CS combinations showed the highest K and viscosity values, respectively. 相似文献
55.
Mehmet Zeynel Cilek Satoshi Hirohata Omer Faruk Hatipoglu Hiroko Ogawa Toru Miyoshi Junko Inagaki Takashi Ohtsuki Hiroshi Harada Shigeshi Kamikawa Shozo Kusachi Yoshifumi Ninomiya 《Cell biology international》2011,35(1):1-8
ADAMTS1 (a disintegrin and metalloproteinase with thrombospondin motifs 1) is an early immediate gene. We have previously reported that ADAMTS1 was strongly induced by hypoxia. In this study, we investigated whether ADAMTS1 promoter‐driven reporter signal is detectable by acute hypoxia. We constructed the GFP (green fluorescent protein) expression vector [AHR (acute hypoxia‐response sequence)‐GFP] under the control of ADAMTS1 promoter and compared it with the constitutive GFP‐expressing vector under the control of CMV (cytomegalovirus promoter‐GFP). We transduced AHR‐GFP and examined whether GFP signals can be detected under the acute hypoxia. When the human umbilical vein [HUVEC (human umbilical vein endothelial cells)] was transduced under normoxia, there were few GFP signals, while CMV‐GFP showed considerable GFP signals. When HUVEC was stimulated with hypoxia, GFP signals from AHR‐GFP gene were induced under hypoxic conditions. Notably, the GFP signals peaked at 3 h under hypoxia. In ischaemic hind limb model, transduced AHR‐GFP showed hypoxic induction of GFP signals. In summary, we have demonstrated that the AHR system induced the reporter gene expression by acute hypoxia, and its induction is transient. This is the first report showing the unique acute hypoxia‐activated gene expression system. 相似文献
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58.
Oxidant/antioxidant parameters and their relationship with medical treatment in multiple myeloma 总被引:3,自引:0,他引:3
Kuku I Aydogdu I Bayraktar N Kaya E Akyol O Erkurt MA 《Cell biochemistry and function》2005,23(1):47-50
Multiple myeloma (MM) is a neoplastic disorder characterized by monoclonal multiplying of plasma cells. Although radiation, environmental factors, viruses and other factors have been suggested as potential causes of the disease, the aetiopathogenesis of MM is still obscure. This clinical study was designed to investigate the role of reactive oxygen species (ROS) in the aetiopathogenesis of the disease and the possible relationships between treatment and ROS production. For this purpose, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities as well as plasma nitric oxide (NO) and malondialdehyde (MDA) levels were measured in 14 MM patients newly diagnosed at stage III. The relationship between the above-mentioned parameters and vincristine-adriamycin-dexamethasone (VAD) therapy were also investigated in the same patients. All the enzyme activities and the parameters of oxidative stress were found to be significantly reduced after VAD therapy. These findings suggest that ROS may be involved in the aetiopathogenesis of MM. Further investigations with a larger cohort of MM patients are needed to provide definitive data about the role of ROS in MM and the alternative therapeutic approaches to MM. 相似文献
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