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231.
Mundle SD; Venugopal P; Cartlidge JD; Pandav DV; Broady-Robinson L; Gezer S; Robin EL; Rifkin SR; Klein M; Alston DE; Hernandez BM; Rosi D; Alvi S; Shetty VT; Gregory SA; Raza A 《Blood》1996,88(7):2640-2647
Our previous studies using in situ end labeling (ISEL) of fragmented DNA revealed extensive apoptotic cell death in the bone marrows (BM) of patients with myelodysplastic syndromes (MDS) involving both stromal and hematopoietic cells. In the present report we show greater synthesis of interleukin-1 beta (IL-1 beta) in 4 hour cultures of density separated BM aspirate mononuclear (BMAM) cells from MDS patients as compared to the cultures of normal BM from healthy donors or lymphoma patients (1.7 +/- 0.37 pg/10(5) cells, n = 29 v 0.42 +/- 0.24 pg/10(5) cells, n = 11, respectively, P = .049). Further, these amounts of IL-1 beta in MDS showed a significant correlation with the extent of apoptosis detected by ISEL in corresponding plastic embedded BM biopsies (r = .480, n = 30, P = .007). In contrast normal BMs did not show any correlation between the two (r = .091, n = 12, P = .779). No significant correlation was found between the amounts of IL-1 beta and % S-phase cells (labeling index; LI%) in MDS determined in BM biopsies using immunohistochemistry following in vivo infusions of iodo- and/or bromodeoxyuridine. Neither anti-IL-1 beta antibody nor IL-1 receptor antagonist blocked the apoptotic death of BMAM cells in 4 hour cultures (n = 5) determined by ISEL (apoptotic index; AI%), although the latter led to a dose-dependent accumulation of active IL-1 beta in the culture supernatants. On the other hand, a specific tetrapetide- aldehyde inhibitor of ICE significantly retarded the apoptotic death of BMAM cells at 1 mumol/L in 5/6 MDS cases studied (AI% = 2.99 +/- 0.30 in controls v 1.58 +/- 0.40 with ICE-inhibitor, P = .05) and also reduced the levels of active IL-1 beta synthesized (5.59 +/- 2.63 v 2.24 +/- 0.93 pg/10(6) cells, respectively). In normal cells, neither IL-1 blockers nor the ICE inhibitor showed any effect on the marginal increase in apoptosis observed in 4 hour cultures. Our data thus suggest a possible involvement of an ICE-like protease in the intramedullary apoptotic cell death in the BMs of MDS patients. 相似文献
232.
Lyman SD; Seaberg M; Hanna R; Zappone J; Brasel K; Abkowitz JL; Prchal JT; Schultz JC; Shahidi NT 《Blood》1995,86(11):4091-4096
The flt3 ligand is a growth factor that stimulates the proliferation of hematopoietic progenitor and stem cells. We established a sensitive enzyme-linked immunosorbent assay (ELISA) to measure the concentration of flt3 ligand in plasma or serum from normal individuals, as well as in patients with hematopoietic disorders. Concentrations of flt3 ligand in plasma or serum from normal individuals were quite low: only 12% (7 of 60) of normal individuals had flt3 ligand levels above 100 pg/mL (the limit of detection). In contrast, 86% (19 of 22) of samples from patients with Fanconi anemia and 100% (eight of eight) of samples from patients with acquired aplastic anemia had plasma or serum levels above 100 pg/mL. Mean plasma or serum concentrations (calculated by assigning a value of 0 pg/mL to any sample reading below the level of detection) were as follows: normal volunteers, 14 pg/mL; patients with Fanconi anemia, 1,331 pg/mL; and patients with acquired aplastic anemia, 460 pg/mL. Concentrations of flt3 ligand in blood are, therefore, specifically elevated to a level that may be physiologically relevant in hematopoietic disorders with a suspected stem cell component. The elevated flt3 ligand concentrations in these individuals may be part of a compensatory hematopoietic response to boost the level of progenitor cells. 相似文献
233.
背景与目的氧化应激是血管疾病发病机制中重要的病原学因素。我们假设:氧化应激可以预测健康人群中的早期动脉粥样硬化。为此,本研究调查了氧化应激标志物和早期动脉粥样硬化之间的关系。方法用超声检测140个不吸烟、无动脉粥样硬化的健康者颈动脉内膜中膜厚度。通过测量血浆中 相似文献
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238.
Low-temperature storage of bone marrow in nitrogen vapor-phase refrigerators: decreased temperature gradients with an aluminum racking system 总被引:1,自引:0,他引:1
Large temperature gradients may exist in nitrogen vapor-phase refrigerators. Cryopreserved cells stored at higher levels may be considerably warmer than those stored closer to the liquid nitrogen reservoir. To decrease this temperature gradient, racking systems constructed of aluminum were placed in marrow storage refrigerators. The higher heat conductivity of aluminum resulted in a vapor-phase temperature gradient of only 5.9 degrees C at 22.5 inches above the liquid, as compared to the gradient of 86 degrees C seen with steel frames in a similar refrigerator. Temperature fluxes were minimal with lid opening or nitrogen filling. The thicker frame size and loss of the lowest storage level resulted in a storage capacity 63 percent of that achievable with steel frames and liquid immersion. Consumption of nitrogen was estimated to be 174 to 220 percent of the static usage in this model of refrigerator with 6 inches of nitrogen, but comparable to the consumption expected with full immersion of the racking system, regardless of frame construction. These data demonstrate the feasibility of achieving very low, stable, cryogenic temperatures in a vapor-phase refrigerator. 相似文献
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Lesny P; Killick SR; Tetlow RL; Robinson J; Maguiness SD 《Human reproduction update》1998,4(4):440-445
This study was designed to assess junctional zone contractions(JZ) during cycles of in-vitro fertilization (IVF) and embryotransfer in oocyte donors exposed to a long protocol regimefor ovarian stimulation. Real-time transvaginal ultrasound andadvanced audio-visual and computer technology were used to evaluatethe contraction pattern, frequency and velocity. At the timeof down-regulation JZ contractions were not observed. After7 days of superovulation all patients displayed cervico-fundal,fundo-cervical and random contractions. Cervico-fundal wavesdominated the picture at the time of human chorionic gonadotrophininjection. However, the activity was strongest on the day ofoocyte retrieval. At the time the percentage of opposing wavesincreased and fundo-cervical waves disappeared. The highestwave frequency and velocity (4.29±0.68 waves/min and2.73±0.54 mm/s respectively) were observed at the timeof oocyte retrieval. All patients had some JZ activity on days2, 3, and 4 after oocyte retrieval but regular wave-like contractilitygradually decreased and only single random movements were seenon day 4 after oocyte retrieval. In conclusion, JZ activitythroughout the IVF cycle is more exaggerated when compared tothe results reported from observations of the natural cyclebut follows a similar pattern. This fact can probably be explainedby the vastly different hormone levels. Higher JZ activity andcorrespondingly increased mobility of the endometrium may impairits receptivity and affect implantation. 相似文献