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101.
Blood smears stained with Wright-Giemsa were obtained from 124 patients with pathologically confirmed cutaneous T cell lymphoma (CTCL), 70 patients with various other cutaneous disorders, and ten healthy adult volunteers. These were examined in a blinded fashion for atypical lymphocytes with cerebriform nuclei (CLs), which were characterized further according to cell diameter. CLs, comprising up to 15% of lymphocytes in smears, were observed in 20% of the patients with benign dermatitis. CLs, comprising up to 89% of lymphocytes in smears, were found in 22%, 30%, 50%, and 96% of patients with patch, plaque, tumor, and erythrodermic CTCL, respectively. Large-diameter CLs (15 to 20 micron) were observed only in smears from patients with CTCL. Total CL counts above 15 per 100 lymphocytes and/or the presence of large CLs occurred in 33 of 49 (67%) patients with erythrodermic disease and in only two patients with other skin manifestations. Blood smears obtained at the time of cytogenetic studies indicated that a total CL count above 15% was the smear criterion that correlated best with the demonstration of a chromosomally abnormal malignant clone in the blood. The presence of large CLs per se, although also predictive of a malignant clone, was less useful. Multivariate survival analysis showed that the duration of disease before the blood smear and the proportion of large CLs within the total CL population were the covariates that correlated most significantly with survival. We speculate that the reduced survival of patients with increased proportions of large CLs in smears reflects the presence of polyploid malignant lymphocytes in the blood.  相似文献   
102.
Adhesion molecules play a role in the migration of hematopoietic progenitor cells and regulation of hematopoiesis. To study whether the mobilization process is associated with changes in expression of adhesion molecules, the expression of CD31, CD44, L-selectin, sialyl Lewisx, beta 1 integrins very late antigen 4 (VLA-4) and VLA-5, and beta 2 integrins lymphocyte function-associated 1 and Mac-1 was measured on either bone marrow (BM) CD34+ cells or on peripheral blood CD34+ cells mobilized with a combination of granulocyte colony- stimulating factor (G-CSF) and chemotherapy. beta 1 integrin VLA-4 was expressed at a significantly lower concentration on peripheral blood progenitor cells than on BM CD34+ cells, procured either during steady- state hematopoiesis or at the time of leukocytapheresis. No differences in the level of expression were found for the other adhesion molecules. To obtain insight in which adhesion molecules may participate in the homing of peripheral blood stem cells (PBSCs), the number of CD34+ cells expressing these adhesion molecules present in leukocytapheresis material was quantified and correlated with hematopoietic recovery after intensive chemotherapy in 27 patients. The number of CD34+ cells in the subset defined by L-selectin expression correlated significantly better with time to platelet recovery after PBSC transplantation (r = - .86) than did the total number of CD34+ cells (r = -.55). Statistical analysis of the relationship between the number of CD34+L-selectin+ cells and platelet recovery resulted in a threshold value for rapid platelet recovery of 2.1 x 10(6) CD34+ L-selectin+ cells/kg. A rapid platelet recovery (< or = 14 days) was observed in 13 of 15 patients who received > or = 2.1 x 10(6) CD34+ L-selectin+ cells/kg (median, 11 days; range, 7 to 16 days), whereas 10 of 12 patients who received less double positive cells had a relative slow platelet recovery (median, 20 days; range, 13 to 37 days). The L-selectin+ subpopulation of CD34+ cells also correlated better with time to neutrophil recovery (r = - .70) than did the total number of reinfused CD34+ cells (r = -.51). However, this latter difference failed to reach statistical significance. This study suggests that L-selectin is involved in the homing of CD34+ cells after PBSC transplantation.  相似文献   
103.
Chronic granulomatous disease (CGD) results from defects in the phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, central to which is the membrane-bound cytochrome b-245. The cytochrome is composed of two protein subunits, the larger (gp91-phox) being deficient in X-linked CGD. In this study, we have analyzed expression of the cytochrome subunits in B-cell lines from two autosomal CGD patients for whom the disease is caused by deficiency of p22-phox, the smaller subunit. We report the presence of a 65-kD precursor of gp91- phox in the membrane fraction of both p22-phox-deficient cell lines, corresponding to the core protein with N-linked carbohydrate side chains in the high mannose form. Expression of p22-phox in these cells resulted in functional correction of NADPH oxidase. In addition, gp91- phox in the reconstituted cells was processed to its terminally glycosylated form. These data suggest that the association of the 65-kD gp91-phox precursor with p22-phox is a prerequisite for processing of the carbohydrate side chains to the complex form in the Golgi. The detection of this precursor will enable characterization of mutations disrupting the subunit interaction (either naturally occurring or derived by in vitro mutagenesis) and so aid in structure-function analysis of cytochrome b-245. Reconstitution of p22-phox-deficient cells shows the potential of gene therapy for this autosomal form of CGD.  相似文献   
104.
The Philadelphia (Ph) translocation t(9;22)(q34;q11) occurs frequently in chronic myeloid leukemia (CML) but is less common in acute lymphoblastic leukemia (ALL) and rare in acute myeloid leukemia (AML). In most cases of CML and some cases of Ph+ ALL the protooncogene ABL from 9q34 is translocated to the breakpoint cluster region (bcr) of the BCR gene at 22q11 to form a chimeric gene encoding a novel 210-kd protein (P210 BCR-ABL) with enhanced tyrosine kinase activity. In other patients with Ph+ ALL and Ph+ AML, the breakpoint probably occurs in the first intron of the BCR gene; this results in a smaller chimeric gene which encodes a P190 BCR-ABL. We studied a patient with AML (FAB M6) arising de novo who had a "masked" Ph chromosome in association with extensive karyotypic changes. The leukemic cells initially showed rearrangement of the bcr, presence of a hybrid mRNA, and expression of the P210 BCR-ABL. These changes were absent in remission. These results support the concept that the BCR-ABL chimeric gene plays a crucial role in leukemogenesis but suggest that factors other than the position of the breakpoint in the BCR gene determine the lineage of the target cell for malignant transformation.  相似文献   
105.
Background: Off-pump Coronary Artery Bypass (OPCAB) has become the standard surgical treatment of Coronary Artery Disease in most centres in India. It is clear from the current evidence that, in certain patients, OPCAB offers advantages over conventional Coronary Artery Bypass Grafting (CABG). Experience of this procedure in the Armed Forces is highlighted.  相似文献   
106.
107.

Background and purpose:

We have previously shown that treatment with zinc plus cyclo-(His-Pro) (CHP) significantly stimulated synthesis of the insulin degrading enzyme and lowered plasma insulin and blood glucose levels, alongside improving oral glucose tolerance in genetically type 2 diabetic Goto-Kakizaki (G-K) rats and in aged obese Sprague-Dawley (S-D) rats. Thus, we postulated that zinc plus CHP (ZC) treatment might also improve body weight control in these rats. We therefore determined the effects of ZC treatment on body weights in both genetically diabetic, mature G-K rats and non-diabetic, obese S-D rats.

Experimental approach:

G-K rats aged 1.5–10 months and non-diabetic overweight or obese S-D rats aged 6–18 months were treated with 0–6 mg CHP plus 0–10 mg zinc·L−1 drinking water for 2–4 weeks, and changes in weight, serum leptin and adiponectin levels, food and water intakes were measured.

Key results:

The optimal dose of CHP (in combination with zinc) to reduce weight and plasma leptin levels and to increase plasma adiponectin levels was close to 0.1 mg·kg−1·day−1, in either mature G-K rats and aged overweight or obese S-D rats. Food and water intake significantly decreased in ZC treated rats in both aged S-D rats and mature G-K rats, but not in young S-D and G-K rats.

Conclusions and implications:

ZC treatment improved weight control and may be a possible treatment for overweight and obesity.  相似文献   
108.
„ Jede Blutung unbekannter Ursache kann eine erworbene H?mophilie sein“, erkl?rte Dr. Andreas Tiede, Hannover.  相似文献   
109.
The cytoplasmic domain of myelin protein zero (MPZ), the principal protein of peripheral myelin, undergoes phosphorylation on several serine residues and a tyrosine group that is maximal during peak nerve myelination. Mutations that could affect MPZ phosphorylation cause the inherited neuropathy, Charcot-Marie-Tooth disease Type 1B. To investigate a possible role for phosphorylation in regulation of MPZ trafficking within the cell, we expressed wild-type and mutated MPZ-enhanced green fluorescent protein (GFP) fusion proteins in cultured Schwann-like cells. Whereas wild-type protein is present almost entirely at the cell surface, mutation of serine 204 to alanine or at a nearby presumed PKC substrate motif (198RSTK201) causes 40-60% of protein to be retained in the cytoplasm. Mutation of S204 to aspartate, which introduces a permanent negative charge, also impairs MPZ movement to the plasma membrane. In contrast, tyrosine 191 mutation has no effect on MPZ cellular distribution. Simultaneous alteration of S204 and Y191 produces much less perturbation of MPZ trafficking than mutation of S204 alone. Colocalization studies showed that mutated MPZ-EGFP trapped in the cytoplasm associates with all organelles in the secretory pathway. Previous studies have shown that cytoplasmic mutations at serine, but not tyrosine phosphorylation sites, abolish MPZ adhesive properties. Our results suggest that this loss of adhesion may be due, at least in part, to a failure of sufficient MPZ to reach the cell surface and that this impaired trafficking is associated with deficient serine phosphorylation in the cytoplasmic domain.  相似文献   
110.
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