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991.
992.
Polymerase chain reaction-based diagnosis of bone marrow involvement in 170 cases of non-Hodgkin lymphoma 总被引:4,自引:0,他引:4
BACKGROUND: Up to the current time, diagnosis of bone marrow (BM) involvement in non-Hodgkin lymphoma (NHL) has been based on morphologic findings. Polymerase chain reaction (PCR) for antigen receptor gene rearrangements has the potential to increase the detection sensitivity of minimal degrees of BM involvement. The authors therefore assessed PCR-based clonalities of BM concurrently with morphology from 170 cases with NHL and evaluated the usefulness of comparative analysis of clonalities between bilateral BMs and the lymph node and the clinical significance of PCR based clonalities of BM. METHODS: Bilateral BM clot sections of 170 cases and 47 lymph nodes were tested for immunoglobulin heavy chain gene rearrangement or T-cell receptor gamma gene rearrangement according to the B- or T-lineage of the lymph node. RESULTS: When compared with morphology, the results of PCR showed an unexpectedly low positive concordance rate of 61.0% for B-cell NHL and 57.1% for T-cell NHL. When the clonality of BM was compared with that of lymph nodes in B-cell NHL, bilateral clonalities of BM showed high concordance with the clonality of the lymph nodes. PCR-based clonality did not show significant impact on survival. CONCLUSIONS: Morphology remains the gold standard in the evaluation of BM involvement by NHL. Although the comparative analysis of BM clonality and that of the lymph nodes is considered a valuable tool that increases the reliability of clonality, PCR-based clonality of BM does not significantly add to the sensitivity of diagnosing BM involvement by NHL. 相似文献
993.
Asiatic acid,a triterpene,induces apoptosis through intracellular Ca2+ release and enhanced expression of p53 in HepG2 human hepatoma cells 总被引:3,自引:0,他引:3
Asiatic acid (AA), a triterpene, decreased viability and induced apoptosis of HepG2 human hepatoma cells in a dose-dependent manner. AA also markedly increased intracellular Ca(2+) level, which was blocked by TMB-8 and dantrolene, intracellular Ca(2+) release blockers, but not by EGTA, an extracellular Ca(2+) chelator. Moreover, AA-induced apoptosis was significantly suppressed by treatment with TMB-8 and dantrolene, suggesting that intracellular Ca(2+) release may play an essential role in the AA-induced apoptosis. In addition, AA profoundly increased protein level of p53, which was also inhibited by BAPTA/AM, an intracellular Ca(2+) chelator, TMB-8 and dantrolene. Treatment with A23187, a Ca(2+) ionophore, or thapsigargin, a Ca(2+)-ATPase inhibitor, alone enhanced p53 nuclear accumulation, indicating that p53 accumulation is dependent on intracellular Ca(2+) increase. Furthermore, the viability of Hep3B, p53-null cells, was much higher than that of HepG2, p53-wild type cells, when treated with AA. Taken together, these results suggest that AA induced apoptosis through increased intracellular Ca(2+), which, in turn, enhanced p53 expression in HepG2 cells. These results further suggest that AA may be a valuable agent for the therapeutic intervention of human hepatomas. 相似文献
994.
995.
Huh WK Gomez-Navarro J Arafat WO Xiang J Mahasreshti PJ Alvarez RD Barnes MN Curiel DT 《Gynecologic oncology》2001,83(2):370-377
OBJECTIVE: The transfer of tumor suppressor genes has been shown to revert the malignant phenotype. In this regard, bax is a pro-apoptotic molecule that also functions as a tumor suppressor. The purpose of this study was to evaluate bax as a gene therapeutic in the context of cervical cancer. METHODS: Efficiency of viral transduction in cervical cancer cell lines and primary cervical cancer cells was evaluated with an adenoviral vector encoding green fluorescent protein and luciferase, respectively. We generated a recombinant adenoviral vector that encodes the bax gene under inducible conditions. To this end, expression of this pro-apoptotic gene was controlled by a Cre-LoxP system. Following infection with the recombinant bax adenovirus, the viability of cervical cancer cell lines and primary cervical cancer cells was evaluated using crystal violet staining and FACS analysis. Apoptotic cell death was monitored using annexin V staining. RESULTS: High levels of viral infection were observed in all cervical cancer cell lines (>85%) and primary cervical cancer cells. Significant cytotoxicity was seen in all cervical cancer cells lines and, more importantly, patient-derived primary cervical cancer cells. Moreover, bax-mediated cell death occurred via an apoptotic pathway. CONCLUSIONS: Our results indicate that a bax recombinant adenoviral vector causes cell death mediated via an apoptotic pathway in multiple cervical cancer cell lines and primary cervical cancer cells. These data suggest that bax may be a candidate for human gene therapy in the setting of cervical carcinoma. 相似文献
996.
The last 40 years, beginning with the first TIROS (television infrared observational satellite) launched on 1 April 1960, has seen an explosion of earth environmental satellite systems and their capabilities. They can provide measurements in globe encircling arrays or small select areas, with increasing resolutions, and new capabilities. Concurrently there are expanding numbers of existing and emerging infectious diseases, many distributed according to areal patterns of physical conditions at the earth's surface. For these reasons, the medical and remote sensing communities can beneficially collaborate with the objective of making needed progress in public health activities by exploiting the advances of the national and international space programs. Major improvements in applicability of remotely sensed data are becoming possible with increases in the four kinds of resolution: spatial, temporal, radiometric and spectral, scheduled over the next few years. Much collaborative research will be necessary before data from these systems are fully exploited by the medical community. 相似文献
997.
Mycobacterium avium complex (MAC) frequently disseminates in AIDS patients, where the gastrointestinal tract is a major target organ. While ascites in AIDS patients is common, peritonitis secondary to MAC is rare. We describe the first case of MAC peritonitis in an AIDS patient without underlying cirrhosis, portal hypertension, chylous ascites or peritoneal dialysis. This case highlights the need to be aware of atypical presentations of MAC disease in AIDS patients with a history of disseminated MAC, even those who compliantly take highly active antiretroviral therapy. 相似文献
998.
The feasibility and safety of fluoroscopy-guided percutaneous intramyocardial gene injection in porcine heart 总被引:6,自引:0,他引:6
Gwon HC Jeong JO Kim HJ Park SW Lee SH Park SJ Huh JE Lee Y Kim S Kim DK 《International journal of cardiology》2001,79(1):77-88
BACKGROUND: Catheter-based transendocardial gene injection would be useful for the delivery of genes into the heart. We examined the feasibility and safety of percutaneous intramyocardial gene injections with fluoroscopic guidance alone. METHODS: We performed the procedure through an 8F arterial sheath inserted into the left carotid artery. In protocol 1, a mixture of India ink and normal saline was injected through a needle injection catheter in six pigs. We monitored blood pressure and ECG continuously during the procedure. Echocardiography, left ventriculography, and coronary angiography were performed. All pigs were sacrificed 2 days later and hearts were harvested. In protocol 2, a mixture of India ink and plasmid encoding CAT gene was injected in the same manner in eight pigs. Myocardial tissue was obtained 7 days after the procedure to assess gene expression. In protocol 3, four pigs were intentionally needle-perforated in the ventricular wall and were observed for 7 days. RESULTS: In protocol 1, there was no significant hemodynamic changes or serious arrhythmias during the procedure. Echocardiography and angiography revealed no evidence indicating pericardial effusion or wall motion abnormalities. Harvested hearts revealed one intramyocardial hematoma in a total of 36 injection sites. In protocol 2, the gene expression could be identified in 39 sites out of 48 injections after 7 days. In protocol 3, no animal showed signs indicating cardiac tamponade during the observation period. CONCLUSIONS: Our data suggest that fluoroscopy-guided percutaneous intramyocardial gene injection is a feasible and safe procedure, with no indication of associated significant hemodynamic changes, arrhythmias, or mortality. 相似文献
999.
Huh JI Calvo A Stafford J Cheung M Kumar R Philp D Kleinman HK Green JE 《Oncogene》2005,24(5):790-800
Cancer growth and progression is often critically influenced by the production of vascular endothelial growth factor (VEGF), a key mediator of angiogenesis. VEGF produced by tumor cells stimulates endothelial cell growth through the binding and activation of the KDR/Flk-1 receptor (VEGFR-2) on endothelial cells. Recently, some human breast cancer epithelial cells have been shown to express VEGF receptors, suggesting a potential autocrine-mediated growth stimulation of a subset of cancers by VEGF. We demonstrate that mammary tumors in the C3(1)/Tag transgenic model express VEGF and VEGF receptors and tumor growth is stimulated by this autocrine mechanism. GW654652, an indazolylpyrimidine, is a VEGFRs tyrosine kinase inhibitor that dramatically reduces both angiogenesis and tumor cell growth in this model, as demonstrated using both in vitro and in vivo assays. GW654652 significantly decreased cell proliferation and induced apoptosis in human umbilical vein endothelial cells and M6 mammary tumor cells derived from C3(1)/Tag (Tag: simian virus 40 T-antigen) transgenic mice. A 75% reduction in VEGF-induced angiogenesis was observed with GW654652 using the chick chorioallantoic membrane assay, whereas GW654652 produced an approximately 85% reduction in angiogenesis as assessed by the Matrigel plug assay. A profound inhibitory effect on tumor growth in the C3(1)/Tag transgenic model of human breast cancer was observed with oral administration of GW654652 as measured by delayed tumor onset, decreased multiplicity, reduced tumor volume, and extended animal survival. The antitumor effects of GW654652 were associated with reduced tumor vascularization and no apparent toxicity. Tumor growth, however, rapidly advanced following cessation of treatment. This is the first demonstration that a VEGF receptor inhibitor, GW654652, has a strong inhibitory effect on angiogenesis and tumor progression in a transgenic model of mammary cancer, suggesting that this is a useful approach for preclinical testing of such agents. 相似文献
1000.
Alzheimer's disease versus dementia with Lewy bodies: cerebral metabolic distinction with autopsy confirmation 总被引:16,自引:0,他引:16
Seeking antemortem markers to distinguish Dementia with Lewy bodies (DLB) and Alzheimer's disease (AD), we examined brain glucose metabolism of DLB and AD. Eleven DLB patients (7 Lewy body variant of AD [LBVAD] and 4 pure diffuse Lewy body disease [DLBD]) who had antemortem position emission tomography imaging and autopsy confirmation were compared to 10 autopsy-confirmed pure AD patients. In addition, 53 patients with clinically-diagnosed probable AD, 13 of whom later fulfilled clinical diagnoses of DLB, were examined. Autopsy-confirmed AD and DLB patients showed significant metabolic reductions involving parietotemporal association, posterior cingulate, and frontal association cortices. Only DLB patients showed significant metabolic reductions in the occipital cortex, particularly in the primary visual cortex (LBVAD -23% and DLBD -29% vs AD -8%), which distinguished DLB versus AD with 90% sensitivity and 80% specificity. Multivariate analysis revealed that occipital metabolic changes in DLB were independent from those in the adjacent parietotemporal cortices. Analysis of clinically diagnosed probable AD patients showed a significantly higher frequency of primary visual metabolic reduction among patients who fulfilled later dinical criteria for DLB. In these patients, occipital hypometabolism preceded some clinical features of DLB. Occipital hypometabolism is a potential antemortem marker to distinguish DLB versus AD. 相似文献