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41.
Huntington disease (HD) is a well-defined autosomal dominant neurodegenerative disease caused by CAG repeat expansions in HD gene. There are a significant number of HD cases where this mutation was not found and such cases are named HD-like phenotype (HDL). This article reports 48 patients with HDL phenotype. Patients were analyzed on the presence of mutations in prion (PrP), ferritin and junctophilin-3 (JP-3) genes. None of the patients showed the presence of the mutation in analyzed genes. This could suggest that there is some other gene/genes where the mutation can cause the disease with clinical features of HD.  相似文献   
42.
In this study we analyzed proliferative activity of myeloma cells and a possible correlation with selected clinical data, histological features and survival in 59 patients with newly diagnosed multiple myeloma (27 females and 32 males, mean age 62 years). Imunohistochemical method was applied using Ki-67 antibody on B5-fixed and paraffin-embedded bone marrow specimens to evaluate growth fraction of myeloma cells. Clinical staging was done according to the Durie-Salmon classification (4 patients had stage I disease, 16 patients stage II and 39 patients stage III). The number of Ki-67+ myeloma cells ranged from 1% to 36% (mean value 7%). In 39 of 59 patients (66.1%) number of Ki-67+ cells was less than 10% (cases with low proliferative index). Ki-67 expression significantly correlated with the clinical stage, beta2-microglobulin level, plasma cell morphology, volume of myeloma infiltration and the extent of osteolytic lesions. Patients with increased proliferative index (Ki-67+ cells > or = 10%) showed a significantly shorter survival compared to those with low proliferative index (14 months vs. 36 months, p = 0.023). However, this difference was not shown in multivariate analysis, particularly due to the high correlation between proliferative activity and plasma cell morphology and the volume of myeloma infiltration.  相似文献   
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Dynamic contrast-enhanced MRI (DCEMRI) data were acquired from metastatic and nonmetastatic tumors in rodents to follow the uptake and washout of a low-molecular-weight contrast agent (Gd-DTPA) and a contrast agent with higher molecular weight (P792). The concentration vs. time curves calculated for the tumor rims and centers were analyzed using the two-compartment model (TCM) and a newly developed empirical mathematical model (EMM). The EMM provided improved fits to the experimental data compared to the TCM. Parameters derived from the empirical model showed that the contrast agent washout rate was significantly slower in metastatic tumors than in nonmetastatic tumors for both Gd-DTPA (P < 0.03) and P792 (P < 0.04). The effects of the tumor on blood flow in "normal" tissue immediately adjacent to the tumors were evident: Gd-DTPA uptake and washout rates were much lower in muscle near the tumor (P < 0.05) than normal muscle farther from the tumor. The results suggest that accurate fits of DCEMRI data provide kinetic parameters that distinguish between metastatic and relatively benign cancers. In addition, a comparison of the dynamics of Gd-DTPA and P792 provides information regarding the microenvironment of tumors.  相似文献   
45.
BACKGROUND: The underlying mechanisms of N-methyl-3,4-methylenedioxyamphetamine--MDMA--induced hepatotoxicity are still unknown. The aim of this study was to evaluate hepatic oxido-reductive status in the rats liver after the single and repeated administration of MDMA. METHODS: MDMA was dissolved in distilled water and administered in the doses of 5 mg, 10 mg, 20 mg, and 40 mg/kg. The animals from the acute experiment were treated per os with the single dose of the appropriate solution, through the orogastric tube. The animals from the chronic experiment were treated per os, with the doses of 5, 10, or 20 mg/kg of MDMA every day during 14 days. The control groups were treated with water only. Eight hours after the last dose, the animals were sacrificed, dissected, their livers were rapidly removed, frozen and stored at -70 degrees C until the moment of analysis. The parameters of oxidative stress in the crude mitochondrial fractions of the livers were analyzed. RESULTS: Superoxide dismutase (SOD) activity increased in the livers of the animals that were treated with single doses of MDMA. Chronically treated animals showed the increased SOD activity only after the highest dose (20 mg/kg). The content of reduced glutathione decreased in both groups, but the depletion was much more expressed after the single administration. Lipid peroxidation index increased in dose-dependent manner in both groups, being much higher after the single administration. CONCLUSION: The increased index of lipid peroxidation and the decreased reduced glutathione levels suggested that MDMA application induced the state of oxidative stress in the liver. These changes were much more expressed after the single administration of MDMA.  相似文献   
46.
The effects of different concentrations of N(G)-nitro-L-arginine methyl ester (L-NAME) (0.3, 1, 3, and 10 mM), a non-selective inhibitor of NOS, on the effect of aminophylline on the isometric contraction of the isolated rat hemidiaphragm were investigated. The muscle contractions were induced by direct subtetanic electrical stimulation. Aminophylline (0.36 - 3.60 mM) produced a typical concentration-dependent increase in both parameters of the isometric contraction: tension developed (Td) and the maximum rate of rise of tension (dT/dt max). The second series of additions of aminophylline produced a more pronounced effect. L-NAME (0.3, 1, 3, and 10 mM, 30 min of incubation without stimulation) itself did not change Td and dT/dt max. However, L-NAME (1, 3, and 10 mM) produced a statistically significant potentiation of the effect of aminophylline on Td and dT/dt max.  相似文献   
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48.
BACKGROUND: During short-term storage of hematopoietic cells (HCs) at 4°C a substantial decline in number and in functional capacity of progenitors occurs after 3 days. We hypothesized that physiologic O2 and CO2 concentrations of hematopoietic tissue microenvironment (approx. 3% O2 and approx. 6% CO2) could improve cell viability and functionality during storage at 4°C.
STUDY DESIGN AND METHODS: Mobilized peripheral blood (PB) CD34+ cells from multiple myeloma or non-Hodgkin's lymphoma patients were stored in flasks containing air (approx. 20% O2 and approx. 0.05% CO2) or 3% O2/6% CO2 atmosphere, for 3, 5, and 7 days at 4°C. The total number of cells, the number of cells in G0 or G1 phase of cell cycle, and the apoptosis rate were determined. The functional capacity of stored cells was assessed by the capacity of progenitors to form colonies in methylcellulose (colony-forming cells [CFCs]) and of stem cells to repopulate the bone marrow (BM) of immunodeficient mice (SCID-repopulating cell [SRC] assay).
RESULTS: The total number of viable cells and cells in G1 phase as well as the number of total CFCs were significantly higher at 3% O2/6% CO2 than in air at all time points. Cells in G0 phase and SRC were equally preserved in both conditions.
CONCLUSION: Atmosphere with low O2 and high CO2 concentration (3% O2/6% CO2) in hypothermia (+4°C) during 7 days of storage prevents cell damage and preserves a high number of functional HSCs and progenitors mobilized in PB by granulocyte–colony-stimulating factor.  相似文献   
49.
Familial hairy cell leukemia (HCL) occurs rarely. So far, 26 familial instances of HCL (in 12 families) have been reported in the literature. The consistent human leukocyte antigen (HLA) linkage could not be established in most cases of familial HCL. History of exposure to organic chemicals or employment in woodworking or farming was noted in only two out of 11 affected families. We present two familial cases of HCL as well as a thorough literature review. An influence of HLA or farming themselves on a predisposition to HCL remains unproven but does not rule out an HLA-linked and as yet unidentified gene responsible for increased disease susceptibility. HCL in families is unlikely to be due to random patterning, but there are insufficient data so far to decisively incriminate either HLA-related or environmental causative factors.  相似文献   
50.
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