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61.
Chronic myelocytic leukemia (CML) may display a lymphoproliferative phase (lymphoid blast crisis) that is generally of B cell phenotype. Since lymphoproliferative disorders may occur following bone marrow transplantation (BMT), it may be difficult to distinguish posttransplant relapse of CML lymphoid blast crisis from de novo lymphoproliferation. Lymphoid blast crisis cells from a patient with CML displayed immunoglobulin heavy chain gene (C mu) rearrangement before BMT. Following BMT the patient developed a lymphoproliferative disorder involving multiple organs. Clonal rearrangement of C mu was demonstrated in several involved tissues. The rearranged C mu restriction fragment was distinct from that displayed before BMT. Additionally, rearrangement of the breakpoint cluster region (bcr) was demonstrated in the pretransplant blast crisis sample, but not in the posttransplant lymphoproliferation samples, thus confirming that these lymphoproliferative disorders were distinct. Molecular genetic techniques offer powerful diagnostic tools for monitoring the course of patients with CML undergoing BMT. 相似文献
62.
A Hirsch F Windhausen JG Tijssen AJ Oude Ophuis WJ van der Giessen PM van der Zee JH Cornel FW Verheugt RJ de Winter 《European heart journal》2009,30(6):645-654
AIMS: In several observational studies, revascularization is associated with substantial reduction in mortality in patients with non-ST-segment elevation acute coronary syndrome (nSTE-ACS). This has strengthened the belief that routine early angiography would lead to a reduction in mortality. We investigated the association between actual in-hospital revascularization and long-term outcome in patients with nSTE-ACS included in the ICTUS trial. METHODS AND RESULTS: The study population of the present analysis consists of ICTUS participants who were discharged alive after initial hospitalization. The ICTUS trial was a randomized, controlled trial in which 1200 patients were randomized to an early invasive or selective invasive strategy. The endpoints were death from hospital discharge until 4 year follow-up and death or spontaneous myocardial infarction (MI) until 3 years. Among 1189 patients discharged alive, 691 (58%) underwent revascularization during initial hospitalization. In multivariable Cox regression analyses, in-hospital revascularization was independently associated with a reduction in 4 year mortality and 3 year event rate of death or spontaneous MI: hazard ratio (HR) 0.59 [95% confidence interval (CI) 0.37-0.96] and 0.46 (95% CI 0.31-0.68). However, when intention-to-treat analysis was performed, no differences in cumulative event rates were observed between the early invasive and selective invasive strategies: HR 1.10 (95% CI 0.70-1.74) for death and 1.27 (95% CI 0.88-1.85) for death or spontaneous MI. CONCLUSION: The ICTUS trial did not show that an early invasive strategy resulted in a better outcome than a selective invasive strategy in patients with nSTE-ACS. However, similar to retrospective analyses from observational studies, actual revascularization was associated with lower mortality and fewer MI. Whether an early invasive strategy leads to a better outcome than a selective invasive strategy cannot be inferred from the observation that revascularized patients have a better prognosis in non-randomized studies. 相似文献
63.
We wished to examine the role of transforming growth factor-beta (TGF- beta) in the regulation of human lymphoma cell growth. The RL cell line is an immunoglobulin M (IgM)+, IgD+ B lymphoma cell line, which does not constitutively express receptors for TGF-beta, and thus has lost the ability to respond to the inhibitory effects of TGF-beta. We demonstrate here that anti-Ig antibodies can efficiently upregulate the expression of TGF-beta receptors and promote sensitivity to growth inhibition by TGF-beta. Furthermore, because TGF-beta has been shown to function in late G1 of the cell cycle, we examined the ability of TGF- beta to modulate two tumor suppressor proteins known to be critical regulators of the G1/S transition, Rb and p53. Rb is a 105- to 110-kD phosphoprotein, which has been shown to maintain its growth suppressive function when it is found in the hypophosphorylated state. Wild-type p53 is a 53-kD phosphoprotein that appears to be important in preventing cell-cycle progression and promoting apoptosis in cells with DNA damage, whereas mutant p53 can overcome those functions. We show here that TGF-beta treatment of phorbol myristate acetate (PMA) or anti- Ig-activated RL cells results in growth inhibition through a dual effect on Rb and mutant p53. After TGF-beta treatment, we observe a predominance of Rb in the hypophosphorylated, growth suppressive form. In addition, we show a decrease in levels of mRNA and protein for mutant p53. We also show that, although these changes are sufficient to halt progression through the cell cycle, the cells do not appear to undergo extensive programmed cell death following 72 hours of TGF-beta treatment. Thus, although these lymphoma cells maintain the capacity to be negatively growth regulated by TGF-beta, the ability of TGF-beta to induce apoptosis must be independently controlled. 相似文献
64.
Clinical features and serum antinuclear antibodies in 230 Danish patients with systemic sclerosis 总被引:5,自引:2,他引:5
Jacobsen S; Halberg P; Ullman S; Van Venrooij WJ; Hoier-Madsen M; Wiik A; Petersen J 《Rheumatology (Oxford, England)》1998,37(1):39-45
The objective was to investigate the relationship between the presence of
different types of antinuclear antibodies (ANA) in patients with systemic
sclerosis (SSc) and the presence of clinical features. Sera from 230
patients with SSc were tested for the presence of ANA, including
anticentromere antibodies (ab), antitopoisomerase I ab, anti- U1 RNP ab and
antinucleolar ab, including anti-Th RNP, anti-U3 RNP and anti-U17 RNP.
Clinical features were registered prospectively in a clinical database.
Eighty-two per cent of the patients were women. The median age was 58 yr
(45-67, quartiles) and median age at disease onset was 44 (30-55) yr. ANA
were found in 86% of the patients (anticentromere: 34%; antitopoisomerase
I: 14%; anti-U1 RNP: 6.5%; antinucleolar total: 16%; anti-Th RNP: 2.2%;
anti-U3 RNP: 3.5%; anti- U17 RNP: 0%). Anticentromere ab were found to be
related to a high prevalence of calcinosis, telangiectasia, digital ulcers,
acrosclerosis, primary biliary cirrhosis, isolated reduction of pulmonary
diffusing capacity, and a low prevalence of radiological evidence of
pulmonary fibrosis. Antitopoisomerase I ab were associated with a high
prevalence of digital joint deformity, distal osteolysis, radiological
signs of pulmonary fibrosis, a low prevalence of calcinosis and late onset
of disease. Anti-U1 RNP ab were related to a high prevalence of arthritis
and myositis, a low prevalence of calcinosis, and early disease onset. The
presence of antinucleolar ab, including anti-U3 RNP and anti-Th RNP, was
not significantly related to any particular clinical features in this
study; possibly due to the small number of patients with these ab. The
presence of anticentromere, antitopoisomerase I and anti-U1 RNP ab in the
serum was also found to have previously described clinical correlations in
a group of Danish SSc patients.
相似文献
65.
Purified populations of natural killer (NK) cells were obtained from mice with severe combined immune deficiency (SCID). SCID spleen cells were cultured and activated with recombinant human interleukin-2 (rhIL- 2) in vitro. The activated NK cells were then transferred with syngeneic BALB/c bone marrow cells (BMC) and rhIL-2 into lethally irradiated syngeneic recipients to determine their effect on long-term hematopoietic reconstitution. On analysis, the transfer of rhIL-2- activated NK cells along with BMC resulted in significant increases in splenic and BM hematopoietic progenitor cells when compared with those for mice not receiving NK cells. Histologic and flow cytometric analysis showed a marked increase in granulocytic and megakaryocytic lineage cells present in the spleens of the mice receiving activated NK cells. Analysis of the peripheral blood indicated that the transfer of activated NK cells with BMC also significantly improved platelet and total white blood cell counts, with increases in segmented neutrophils. Erythroid recovery was not affected. Finally, lethally irradiated mice receiving activated NK cells and rhIL-2 along with limiting numbers of syngeneic BMC showed a marked increase in survival rate. These results show that the use of populations enriched for activated NK cells after syngeneic BM transplantation (BMT) has a profound enhancing effect on engraftment primarily affecting megakaryocytic and granulocytic cell reconstitution. Therefore, the transfer of activated NK cells and rhIL- 2 may be of clinical use to promote hematopoietic reconstitution after BMT. 相似文献
66.
本实验采用性腺摘除或经假摘除手术的两性SD大鼠,其中部分动物分别予以睾酮(T)或雌二醇(E_2),观察它们在急性饥饿或非饥饿状态下血清T_4、TSH与T浓度变化。结果提示急性饥饿可使雄鼠甲状腺合成或分泌T_4和性腺分泌睾酮减少,从而不完全地抑制了雄激素所介导的对垂体TSH分泌的兴奋作用。外源性T替代虽然可以使去势雄鼠血清T浓度恢复正常,但却无兴奋TSH分泌的作用;饥饿组去势雄鼠接受外源性T后血清TSH更为减少。提示外源性T可抑制此组雄鼠垂体TSH合成及(或)释放。 相似文献
67.
68.
Sjors FPJ Coppus Jose I Emparanza Julie Hadley Regina Kulier Susanne Weinbrenner Theodoros N Arvanitis Amanda Burls Juan B Cabello Tamas Decsi Andrea R Horvath Marcin Kaczor Gianni Zanrei Karin Pierer Katarzyna Stawiarz Regina Kunz Ben WJ Mol Khalid S Khan 《BMC medical education》2007,7(1):1-10
Background
Little research has been conducted to investigate role stress experienced by faculty members in medical schools in developing countries. This becomes even more important when the process of reform in medical education has already taken place, such as the case of Iran. The objectives of this study were to investigate and assess the level and source of role-related stress as well as dimensions of conflict among the faculty members of Iranian medical schools. Variables like the length of academic work, academic rank, employment position, and the departments of affiliation were also taken into consideration in order to determine potentially related factors.Methods
A survey was conducted at three different ranks of public medical schools. The validated Organizational Role Stress Scale was used to investigate the level of role stress and dimensions of role conflict among medical faculty members. The response rate was 66.5%.Results
The findings show that role stress was experienced in high level among almost all faculty members. All three studied medical schools with different ranks are threatened with relatively the same levels of role stress. Specific differences were found among faculty members from different disciplines, and academic ranks. Also having permanent position and the length of services had significant correlation with the level of role stress. The major role- related stress and forms of conflict among faculty members were role overload, role expectation conflict, inter-role distance, resource inadequacy, role stagnation, and role isolation.Conclusion
The most role-related stressors and forms of conflict among faculty members include too many tasks and everyday work load; conflicting demands from colleagues and superiors; incompatible demands from their different personal and organizational roles; inadequate resources for appropriate performance; insufficient competency to meet the demands of their role; inadequate autonomy to make decision on different tasks; and a feeling of underutilization. The findings of this study can assist administrators and policy makers to provide an attractive working climate in order to decrease side effects and consequences of role stress and to increase productivity of faculty members. Furthermore, understanding this situation can help to develop coping strategies in order to reduce role-related stress. 相似文献69.
Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder, occurring predominantly in women. We studied by flow cytofluorimetry the T cell subsets in men and women with ITP and compared them with healthy sex-matched volunteers. In healthy controls, women were found to have higher proportions of T helper/inducer (Th/i) and lower T suppressor/cytotoxic (Ts/c) lymphocytes and consequently higher Th/i:Ts/c ratios than men. Accordingly, in clinical surveys, patients and controls should be matched for sex for proper comparisons. In patients with ITP in its active phase, an imbalance in T cell subsets was found in both sexes. The perturbation was more severe in women who had a marked decrease in number and proportion of Th/i lymphocytes and an increase in the proportion of Ts/c lymphocytes, whereas in men only, the proportion of Th/i lymphocytes was decreased. When patients with active disease were compared to those with ITP in remission, the decrease in Th/i subsets still persisted in both sexes but the Ts/c subset in women had returned to normal proportions. Therefore, the immune imbalance in ITP is more marked in women than men; imbalances in both Th/i and Ts/c are present in women while Ts/c appears not to be involved in men. 相似文献
70.
SL Dorman SM Graham J Paniker S Phalira WJ Harrison 《Malawi medical journal : the journal of Medical Association of Malawi》2014,26(4):119-123