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131.
132.
Grimwade D Outram SV Flora R Ings SJ Pizzey AR Morilla R Craddock CF Linch DC Solomon E 《Cancer research》2002,62(16):4730-4735
The nature of hemopoietic progenitors subject to leukemic transformation in acute myeloid leukemia (AML) has not been clearly defined. To address this issue, we have used DNase I hypersensitivity assays to study the chromatin structure surrounding the T-lineage-affiliated CD2 gene in the acute promyelocytic subtype of AML (APL). Upstream and downstream flanking regions of CD2 were found to be hypersensitive to DNase I in primary APL blasts, with an identical pattern of hypersensitive sites to those detected in cells of T-lineage. All of the sites were confirmed to be inaccessible to DNase I in B-lineage leukemia cells. The demonstration of T-cell-associated chromatin features in primary APL blasts has implications for the origin of APL that may arise in more primitive progenitors than previously considered to be the case. 相似文献
133.
Travis LB Gospodarowicz M Curtis RE Clarke EA Andersson M Glimelius B Joensuu T Lynch CF van Leeuwen FE Holowaty E Storm H Glimelius I Pukkala E Stovall M Fraumeni JF Boice JD Gilbert E 《Journal of the National Cancer Institute》2002,94(3):182-192
BACKGROUND: Lung cancer is a frequent cause of death in patients cured of Hodgkin's disease, but the contributions of chemotherapy, radiotherapy, and smoking are not well described. We quantified the risk of treatment-associated lung cancer, taking into account tobacco use. METHODS: Within a population-based cohort of 19 046 Hodgkin's disease patients (diagnosed from 1965 through 1994), a case-control study of lung cancer was conducted. The cumulative amount of cytotoxic drugs, the radiation dose to the specific location in the lung where cancer developed, and tobacco use were compared for 222 patients who developed lung cancer and for 444 matched control patients. All statistical tests were two-sided. RESULTS: Treatment with alkylating agents without radiotherapy was associated with increased lung cancer risk (relative risk [RR] = 4.2; 95% confidence interval [CI] = 2.1 to 8.8), as was radiation dose of 5 Gy or more without alkylating agents (RR = 5.9; 95% CI = 2.7 to 13.5). Risk increased with both increasing number of cycles of alkylating agents and increasing radiation dose (P for trend <.001). Among patients treated with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP), risk increased with cumulative amounts of mechlorethamine and procarbazine (P<.001) when evaluated separately. Statistically significantly elevated risks of lung cancer were apparent within 1-4 years after treatment with alkylating agents, whereas excess risk after radiotherapy began 5 years after treatment and persisted for more than 20 years. Risk after treatment with alkylating agents and radiotherapy together was as expected if individual excess risks were summed. Tobacco use increased lung cancer risk more than 20-fold; risks from smoking appeared to multiply risks from treatment. CONCLUSIONS: Past treatments with alkylating agents and radiation therapy for Hodgkin's disease were associated with an increased risk of lung cancer in a dose-dependent and additive fashion. The precise risk estimates, however, should be interpreted cautiously, given the possible residual and enhancing effects of tobacco. 相似文献
134.
Tsirigotis P Venetis E Rontogianni D Dervenoulas J Kontopidou F Apostolidis P 《Leukemia research》2002,26(10):965-966
A 67-year-old woman was admitted for investigation of pancytopenia. Bone marrow biopsy was compatible with myelodysplastic syndrome (MDS) with fibrosis. For the next 20 months the patient received transfusions of packed red cells, while a 3-month-trial of erythropoetin was unsuccesful. She was then treated with thalidomide 400mg per day. During the next months, a gradual rise in Hb value was noticed and the patient eventually became transfusion independent. Repeat bone marrow biopsy revealed a significant decrease on the degree of fibrosis. Thalidomide has shown excellent results in the treatment of multiple myeloma probably due to its anti-angiogenic activity. It is possible that in our patient thalidomide acted as an anti-fibrotic agent. It will be very interesting to test this novel activity of thalidomide in a large number of patients. 相似文献
135.
Lazzaro Repetto Lucia Fratino Riccardo A Audisio Antonella Venturino Walter Gianni Marina Vercelli Stefano Parodi Denise Dal Lago Flora Gioia Silvio Monfardini Matti S Aapro Diego Serraino Vittorina Zagonel 《Journal of clinical oncology》2002,20(2):494-502
PURPOSE: To appraise the performance of Comprehensive Geriatric Assessment (CGA) in elderly cancer patients (> or = 65 years) and to evaluate whether it could add further information with respect to the Eastern Cooperative Oncology Group performance status (PS). PATIENTS AND METHODS: We studied 363 elderly cancer patients (195 males, 168 females; median age, 72 years) with solid (n = 271) or hematologic (n = 92) tumors. In addition to PS, their physical function was assessed by means of the activity of daily living (ADL) and instrumental activities of daily living (IADL) scales. Comorbidities were categorized according to Satariano's index. The association between PS, comorbidity, and the items of the CGA was assessed by means of logistic regression analysis. RESULTS: These 363 elderly cancer patients had a good functional and mental status: 74% had a good PS (ie, lower than 2), 86% were ADL-independent, and 52% were IADL-independent. Forty-one percent of patients had one or more comorbid conditions. Of the patients with a good PS, 13.0% had two or more comorbidities; 9.3% and 37.7% had ADL or IADL limitations, respectively. By multivariate analysis, elderly cancer patients who were ADL-dependent or IADL-dependent had a nearly two-fold higher probability of having an elevated Satariano's index than independent patients. A strong association emerged between PS and CGA, with a nearly five-fold increased probability of having a poor PS (ie, > or = 2) recorded in patients dependent for ADL or IADL. CONCLUSION: The CGA adds substantial information on the functional assessment of elderly cancer patients, including patients with a good PS. The role of PS as unique marker of functional status needs to be reappraised among elderly cancer patients. 相似文献
136.
We report two patients, one with sternal cleft, haemangiomas, supraumbilical midline raphe and the other with a sternal cleft, haemangiomas, coarctation of the aorta with a right aortic arch. 相似文献
137.
De Flora S; Camoirano A; Bagnasco M; Bennicelli C; Corbett GE; Kerger BD 《Carcinogenesis》1997,18(3):531-537
Estimates of the overall reducing capacity of hexavalent chromium(VI) in
some human body compartments were made by relating the specific reducing
activity of body fluids, cell populations or organs to their average
volume, number, or weight. Although these data do not have absolute
precision or universal applicability, they provide a rationale for
predicting and interpreting the health effects of chromium(VI). The
available evidence strongly indicates that chromium(VI) reduction in body
fluids and long-lived non-target cells is expected to greatly attenuate its
potential toxicity and genotoxicity, to imprint a threshold character to
the carcinogenesis process, and to restrict the possible targets of its
activity. For example, the chromium(VI) sequestering capacity of whole
blood (187-234 mg per individual) and the reducing capacity of red blood
cells (at least 93-128 mg) explain why this metal is not a systemic
toxicant, except at very high doses, and also explain its lack of
carcinogenicity at a distance from the portal of entry into the organism.
Reduction by fluids in the digestive tract, e.g. by saliva (0.7-2.1 mg/day)
and gastric juice (at least 84- 88 mg/day), and sequestration by intestinal
bacteria (11-24 mg eliminated daily with feces) account for the poor
intestinal absorption of chromium(VI). The chromium(VI) escaping reduction
in the digestive tract will be detoxified in the blood of the portal vein
system and then in the liver, having an overall reducing capacity of 3300
mg. These processes give reasons for the poor oral toxicity of chromium(VI)
and its lack of carcinogenicity when introduced by the oral route or
swallowed following reflux from the respiratory tract. In terminal airways
chromium(VI) is reduced in the epithelial lining fluid (0.9-1.8 mg) and in
pulmonary alveolar macrophages (136 mg). The peripheral lung parenchyma has
an overall reducing capacity of 260 mg chromium(VI), with a slightly higher
specific activity as compared to the bronchial tree. Therefore, even in the
respiratory tract, which is the only consistent target of chromium(VI)
carcinogenicity in humans (lung and sinonasal cavities), there are barriers
hampering its carcinogenicity. These hurdles could be only overwhelmed
under conditions of massive exposure by inhalation, as it occurred in
certain work environments prior to the implementation of suitable
industrial hygiene measures.
相似文献
138.
Proton MR spectroscopy in quantitative in vivo determination of fat content in human liver steatosis
Renata Longo Piero Pollesello Claudio Ricci Flora Masutti Bjarne J. Kvam Luisa Bercich Lory S. Croce Piergiovanni Grigolato Sergio Paoletti Benedetto De Bernard Claudio Tiribelli Ludovico Dalla Palma 《Journal of magnetic resonance imaging : JMRI》1995,5(3):281-285
To demonstrate that the lipid volume fraction In liver steatosis can be accurately estimated with in vivo hydrogen-1 magnetic resonance (MR) spectroscopy, the authors developed a calibration procedure based on in vitro MR spectroscopy of lipid extracts from steatotlc liver specimens. The lipid volume fractions determined with the calibration procedure were compared with the results of histomorphometry and with calibrated computed tomographic (CT) data. The volume fraction of fat determined with MR spectroscopy was in good agreement with the CT results, whereas histomorphometry underestimated the amount of hepatic fat. The results indicate that determination of the fat volume fraction in steatotic liver can be achieved noninvasively with MR spectroscopy. 相似文献
139.
D-Penicillamine (DPA), diethyldithiocarbamate (DDC), L-cysteine, ethylenediaminetetraacetic acid (EDTA), cyclohexylenediaminetetraacetic acid (CDTA), and diethylene triamine pentaacetic acid (DTPA) were compared for their efficacy to enhance urinary excretion of Pb, to reduce Pb concentration of body organs, and to restore the enhanced urinary excretion of delta-aminolevulinic acid (delta-ALA), the inhibited activities of blood delta-ALA dehydratase, and renal enzymes in Pb-administered rats (10 mg/kg, po, 4 weeks) with normal or experimentally damaged kidneys. The acute renal damage was induced by uranyl acetate (3 mg/kg, sc, once) prior to treatment with the chelators (0.3 mmol/kg, ip, twice) and evaluated by enhanced urinary excretion of diagnostic enzymes and inhibition in their renal activities. Among thiol chelators, DPA was the most effective followed by DDC in enhancing the urinary excretion of Pb, reducing the concentration of Pb in blood, kidneys and liver, and in restoring Pb-induced biological alterations in urine, blood, and kidneys. Among amino carboxylic acids, DTPA was the most effective and EDTA and CDTA were about equally potent in countering Pb toxicity. Protection was more marked in animals with normal kidneys than in those with acutely damaged kidneys. 相似文献
140.
Transplantation antigens were solubilized either from Sarcoma I (Sal) cells by aqueous autolysis, or from the spleens, lymph nodes and livers of normal A mice by aqueous autolysis followed by proteolysis with papain. The immunogenicity of these preparations was examined by their effect in modifying the rejection of Sal tumor allografts in C57BL/6 recipients and/ or by their capacity to induce the formation of cytotoxic lymphocytes in the spleens or lymph nodes of the immunized animals following a single intraperitoneal administration of the soluble antigen. Depending on the dose of antigen, and the interval between immunization and allografting, either tumor enhancement or accelerated tumor rejection was obtained. The latter was shown to be accompanied by cellular immunity, primarily in the lymph nodes of the sensitized animals; however, under certain conditions, cytotoxic lymphocytes were also detectable in the spleen. 相似文献