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101.
MH Sun G Mechtersheimer P Moellera CH Herfarth MV Knebel Doeberitz HK Scharkert T Lehnert J Gebert 《World journal of gastroenterology : WJG》2000,6(3)
AIM To study the clonality of the esophageal carcinosarcoma by using molecular approaches.METHODS Two esophageal carcinosarcomas were included in the study. Tumor area from dysplasticlesion, squamout cell carcinoma, basaloid cell carcinoma and spindle cell elements were microdissectedseparately. Each element was analyzed with 14 microsatellite markers and direct sequenced for p53 gene andras gene mutation.RESULTS Both tumors displayed a typical histologic feature of carcinosarcoma. Both cases showed thedivergent differentiation by immunohistochemistry study. In case 1 the identical LOH at p53 and hMLH1 lociwas detected. The heterogenous LOH was detected only in carcinosarcoma at RB1 and BRCA1 loci, whilethe LOH at ACTC locus was seen only in sarcoma. The same mutation of the splice site of exon 6-intron 6displayed in the two tumor elements. In case 2, a coordinate LOH at RB locus was demonstrated in threetypes of tumor elements: sqamous carcinoma, basaloid carcinoma and spindle cell element. A heterogenousLOH was seen only in spindle cells at TAP1 locus. No mutation in exon 5-8 of p53 gene has been found incase 2. No mutation of K-ras gene was found.CONCLUSION Although the different differentiation, the two elements of esophageal carcinosarcoma mayhave a single clonality. The p53 gene mutation occurred before the two differentiation directions switched.The distinct molecular genotype can be determined through molecular biological analysis. The microsatelliteprofiling can serve as an approach to find out which genetic alteration occurs before or after thedifferentiation is determines. 相似文献
102.
This is the first report describing the efficacy of modafinil therapy for narcolepsy in patients in Taiwan. The purpose of this study was to compare the objective Multiple Sleep Latency Test (MSLT) and the subjective Epworth Sleepiness Scale (ESS) for evaluating the efficacy of modafinil in treating excessive daytime sleepiness in patients with narcolepsy in Taiwan. Ten consecutive patients with narcolepsy-with-cataplexy who were treated with 200 mg/day modafinil for more than 6 months at our sleep center between January 2003 and December 2007 were included in this study. This comparative study was prompted by the requirement of the Bureau of National Health Insurance in Taiwan that modafinil users need to be followed up with MSLTs every 6–12 months. The mean age at onset of narcolepsy onset in these 10 patients was 11.8 ± 3.3 years, and eight (80%) were male. We compared the differences in MSLT and ESS between baseline and follow-up at 6–12 months after starting modafinil therapy using paired t tests. ESS scores (p < 0.001) were considerably more sensitive than MSLT scores (p < 0.05) in documenting efficacy of modafinil and that the improvements in MSLT scores were minimal and remained in the pathologically sleepy range. These findings suggest that the ESS is a more sensitive and clinically meaningful tool to evaluate the efficacy of modafinil in narcolepsy. 相似文献
103.
104.
Bensinger WI; Weaver CH; Appelbaum FR; Rowley S; Demirer T; Sanders J; Storb R; Buckner CD 《Blood》1995,85(6):1655-1658
Peripheral blood stem cells (PBSCs) are widely used in autologous transplantation because of ease of collection and rapid hematopoietic reconstitution. However, PBSCs have rarely been used for allogeneic transplantation because of concerns about donor toxicities from cytokine administration and the theoretical increased risk of graft- versus-host-disease (GVHD) from the large number of T cells infused. Eight patients with advanced malignancies received allogeneic PBSC transplants from genotypically HLA-identical sibling donors. All donors received 5 days of recombinant human granulocyte colony-stimulating factor (rhG-CSF; 16 micrograms/kg/day) subcutaneously and were leukapheresed for 2 days. After treatment of the patient with total body irradiation and cyclophosphamide (n = 7) or etoposide, thiotepa, and cyclophosphamide (n = 1), PBSCs were infused immediately after collection and without modification. All patients received cyclosporine and either methotrexate (n = 6) or prednisone (n = 2) for GVHD prophylaxis, rhG-CSF was well tolerated with mild bone pain requiring acetaminophen occurring in two donors. All patients engrafted and in seven hematopoietic recovery was rapid, with 500 neutrophils/microL achieved by day 18 and 20,000 platelets/microL by day 12. Complete donor engraftment was documented by Y chromosome analysis in all four sex-mismatched donor-recipient pairs tested and by DNA analysis in two sex-matched pairs. One patient died on day 18 of veno-occlusive disease of the liver with engraftment but before chromosome analysis could be performed (results are pending in 1 patient). A second patient died of fungal infection 78 days after transplant. Grade 2 acute GVHD occurred in two patients and grade 3 GVHD occurred in one patient. One patient is 301 days from transplant in remission with chronic GVHD; the remaining five patients are alive and disease free 67 to 112 days after transplantation. Preliminary results indicate that allogeneic PBSCs mobilized by rhG-CSF can provide rapid hematologic recovery without an appreciably greater incidence of acute GVHD than would be expected with marrow. Further follow-up is required to determine the incidence of chronic GVHD and any potential beneficial effects on relapse after transplant. 相似文献
105.
Stem cell factor retards differentiation of normal human erythroid progenitor cells while stimulating proliferation 总被引:5,自引:12,他引:5
Stem cell factor (SCF), the ligand for the c-kit tyrosine kinase receptor, markedly stimulates the accumulation of erythroid progenitor cells in vitro. We now report that SCF delays erythroid differentiation among the progeny of individual erythroid progenitors while greatly increasing the proliferation of these progeny. These effects appear to be independent of an effect on maintenance of cell viability. Highly purified day-6 erythroid colony-forming cells (ECFC), consisting mainly of colony-forming units-erythroid (CFU-E), were generated from human peripheral blood burst-forming units-erythroid (BFU-E). Addition of SCF to the ECFC in serum-free liquid culture, together with erythropoietin (EP) and insulin-like growth factor 1 (IGF-1), resulted in a marked increase in DNA synthesis, associated with a delayed peak in cellular benzidine positivity and a delayed incorporation of 59Fe into hemoglobin compared with cultures without SCF. In the presence of SCF, the number of ECFC was greatly expanded during this culture period, and total production of benzidine-positive cells plus hemoglobin synthesis were ultimately increased. To determine the effect of SCF on individual ECFC, single-cell cultures were performed in both semisolid and liquid media. These cultures demonstrated that SCF, in the presence of EP and IGF-1, acted on single cells and their descendants to delay erythroid differentiation while substantially stimulating cellular proliferation, without an enhancement of viability of the initial cells. This was also evident when the effect of SCF was determined using clones of ECFC derived from single BFU-E. Our experiments demonstrate that SCF acts on individual day-6 ECFC to retard erythroid differentiation while simultaneously providing enhanced proliferation by a process apparently independent of an effect on cell viability or programmed cell death. 相似文献
106.
T Wenzel S M?rsdorf I Sibitz J F Schenck H Griengl W Erdlenbruch W Heinrich B Krischek P Birner J Harenberg 《Seminars in thrombosis and hemostasis》1999,25(1):117-121
In correlation with increased life expectancy of patients, quality of life (QOL) has become a factor of increasing interest by the patient himself and also of importance in health-care planning and recruitment of financial resources. In this context, self-monitoring of long-term anticoagulant treatment might be a strategy that could mean a step forward in health-related as well as general life satisfaction for patients participating in self-monitoring programs. Also, the new strategy of increased home-control of anticoagulant treatment illustrates the complexity of multiple factors that can lead to changes in the subjective feeling and objective aspects of QOL. Our intention in a pilot study was to probe the feasibility of QOL research and relevant factors of influence by retrospectively evaluating data from two groups of outpatients seen in a large treatment center. The high frequency (n = 8 in sample 2) of disturbed sleep as a simple screening indicator stresses the probable importance of undetected depression, which might require treatment and could confound research as to QOL. Instruments to measure QOL in oral anticoagulation self-monitoring should therefore be adapted to the heterogeneous structure of factors in the target population, and include psychological parameters, especially in regard to health-related locus of control and mood. 相似文献
107.
108.
Human burst-forming units-erythroid need direct interaction with stem cell factor for further development 总被引:6,自引:3,他引:6
To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation. 相似文献
109.
Red cells stored in saline-adenine-glucose-mannitol (SAGM) medium were rejuvenated by incubation with phosphoenolpyruvate (PEP) under conditions that can be achieved easily in ordinary blood banking. Regeneration of 2,3 diphosphoglycerate (2,3 DPG) and adenine nucleotides of stored red cells was dependent on the pH of the incubation medium and the incubation time. In red cells stored for 3 and 5 weeks, the optimal pH and incubation time for regeneration of 2,3 DPG and adenine nucleotides were 5.8 and 90 minutes and 6.1 and 60 minutes, respectively. During the incubation of red cells with PEP, methemoglobin was formed; it increased when the medium pH was below 6.0 and the incubation time exceeded 60 minutes. We conclude that incubation at a medium pH of 6.1 for 60 minutes is optimal for the rejuvenation of stored red cells with PEP. Under such incubation conditions, the concentrations of 2,3 DPG and adenine nucleotides in red cells stored for 5 weeks were restored to normal without methemoglobin formation. 相似文献
110.
Jian-Hua Li Tuo Chen Hao Xing Rui-Dong Li Cong-Huan Shen Quan-Bao Zhang Yi-Feng Tao Zheng-Xin Wang 《Hepatobiliary & pancreatic diseases international : HBPD INT》2023,22(3):245-252
Background: Liver transplantation(LT) is the “cure” therapy for patients with hepatocellular carcinoma(HCC). However, some patients encounter HCC recurrence after LT. Unfortunately, there is no effective methods to identify the LT patients who have high risk of HCC recurrence and would benefit from adjuvant targeted therapy. The present study aimed to establish a scoring system to predict HCC recurrence of HCC patients after LT among the Chinese population, and to evaluate whether these patients... 相似文献