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991.
Summary Esorubicin (4 deoxydoxorubicin) is a new analogue of the anthracycline, doxorubicin. This compound lacks the hydroxyl group at 4 position on the amino sugar of the anthracycline. Phase II study was designed to determine the clinical response rate and to define the qualitative and quantitative toxicities of esorubicin in patients with adenocarcinoma of the pancreas. Fifty-eight patients with inoperable adenocarcinoma of the pancreas were entered on the study, 47 were evaluable for response, and 57 were evaluable for toxicity. The dose of esorubicin was 30 mg/m2 for good risk patients and 25 mg/m2 for poor risk patients every 21 days and administered IV push through a side arm of a running IV. Diphenhydramine, 50 mg is administered IM prior to the administration of the drug to block local venous reaction. Subsequent doses of esorubicin were modified according to granulocyte and platelet nadirs and the drug was not administered until recovery of platelets (> 100,000/ul) and wbc (> 3000/ul). Three partial responses, 20 stable, and 31 with increased disease were observed. Forty-seven had severe granulocytopenia (< 250), and two patients had severe thrombocytopenia (< 25,000). One patient experienced a decrease in left ventricular ejection fraction with a total dose of 180 mg/m2. The dose of esorubicin in this study demonstrated that the drug has minimal activity in adenocarcinoma of the pancreas but the toxicity is tolerable. Search should continue for single agents with activity in this disease. 相似文献
992.
S Katzav S Segal M Feldman 《International journal of cancer. Journal international du cancer》1984,33(3):407-415
To find out whether manipulation of H-2 expression on metastatic cells could alter their metastatic properties, we immunoselected in vivo H-2 antigen variants from a metastatic clone of the T10 sarcoma [originating in a (C57BL/6J X C3H.eB)FI mouse] and tested their metastatic capacity. The unselected metastatic cells (IE7) were previously found to express H-2Db and H-2Dk antigens, but they did not express the H-2K antigens of either parental haplotype. Transplantation of IE7 cells into C57BL/6J irradiated mice resulted in loss of H-2Dk expression and a reduction in H-2Db antigen density. Further transplantation of these cells into non-irradiated C57BL/6J mice led to a total loss of H-2 expression. The cells concomitantly lost their metastatic potency. Immunoselection of IE7 cells in C3H.eB irradiated and non-irradiated mice resulted in cells which were H-2Dk-positive but H-2Db-negative. Cells of these selected variants not only retained their metastatic potential, but in fact were far more metastatic than the unselected IE7 cells. Thus, changes in H-2 expression on tumor cells may alter their metastatic potential. In the case of T10 cells, H-2Dk expression seems to be directly involved in their metastatic capacity. 相似文献
993.
Thermic effect of food at rest, during exercise, and after exercise in lean and obese men of similar body weight. 总被引:1,自引:4,他引:1
K R Segal B Gutin A M Nyman F X Pi-Sunyer 《The Journal of clinical investigation》1985,76(3):1107-1112
The thermic effect of food at rest, during 30 min of cycle ergometer exercise, and after exercise was studied in eight lean (mean +/- SEM, 10 +/- 1% body fat, hydrostatically-determined) and eight obese men (30 +/- 2% body fat). The lean and obese mean were matched with respect to age, height, weight, and body mass index (BMI) to determine the relationship between thermogenesis and body composition, independent of body weight. All men were overweight, defined as a BMI between 26-34, but the obese had three times more body fat and significantly less lean body mass than the lean men. Metabolic rate was measured by indirect calorimetry under four conditions on separate mornings, in randomized order, after an overnight fast: 3 h of rest in the postabsorptive state; 3 h of rest after a 750-kcal mixed meal (14% protein, 31.5% fat, and 54.5% carbohydrate); during 30 min of cycling and for 3 h post exercise in the postabsorptive state; and during 30 min of cycling performed 30 min after the test meal and for 3 h post exercise. The thermic effect of food, which is the difference between postabsorptive and postprandial energy expenditure, was significantly higher for the lean than the obese men under the rest, post exercise, and exercise conditions: the increments in metabolic rate for the lean and obese men, respectively, were 48 +/- 7 vs. 28 +/- 4 kcal over 3 h rest (P less than 0.05); 44 +/- 7 vs. 16 +/- 5 kcal over 3 h post exercise (P less than 0.05); and 19 +/- 3 vs. 6 +/- 3 kcal over 30 min of exercise (P less than 0.05). The thermic effect of food was significantly negatively related to body fat content under the rest (r = -0.55), post exercise (r = -0.66), and exercise (r = -0.58) conditions. The results of this study indicate that for men of similar total body weight and BMI, body composition is a significant determinant of postprandial thermogenesis; the responses of obese are significantly blunted compared with those of lean men. 相似文献
994.
PURPOSE: The aim of the study is to show that differences in platelet counts by ethnicity, sex, and age are not explained by environmental factors. METHODS: This is a cross-sectional population-based study of participants in the Third National Health and Nutrition Examination Survey. Our analytic sample included 12,142 participants, of whom 65% were women, 27% were non-Hispanic blacks, and 27% were Mexican Americans. We report weighted geometric mean platelet counts stratified by ethnicity, sex, and age and controlled for indicators of nutritional deficiencies and inflammation. RESULTS: The lowest mean platelet counts were in whites (260x10(3)/microL; 95% confidence interval [CI], 256-264), and the highest were in non-Hispanic blacks (281x10(3)/microL [95% CI, 276-286]). Older men and women of each ethnicity consistently had lower platelet counts than young adults; 60- to 69-year-olds had mean counts 7x10(3)/microL lower (p<0.001) and 70- to 90-year-olds had counts 18x10(3)/microL lower (p<0.001). Even controlling for iron deficiency, women had higher platelet counts than men (275x10(3)/microL; 95% CI, 271-279) versus 256x10(3)/microL (95% CI, 251-260; p<0.001). CONCLUSIONS: Platelet count differences by sex, ethnicity, and age are not explained by environmental covariates known to influence platelet count. 相似文献
995.
Garth Powis Alfred Gallegos Robert T. Abraham Curtis L. Ashendel Loen H. Zalkow Robert Dorr Katerina Dvorakova Sydney Salmon Steadman Harrison John Worzalla 《Cancer chemotherapy and pharmacology》1997,41(1):22-28
Purpose: Studies were conducted on oryzalin (3,5-dinitro-N,N-di(n-propyl)sulfanilamide), a widely used dinitroaniline sulfonamide herbicide, which was identified from plant extracts as an
inhibitor of mitogen- and growth factor-mediated intracellular free Ca2+ ([Ca2+]i) signalling in mammalian cells. Methods and Results: Oryzalin inhibited vasopressin, bradykinin and platelet-derived growth factor [Ca2+]i signalling in Swiss 3T3 fibroblasts with IC50 values of 14, 16 and 18 μM, respectively. 45Ca2+ uptake into nonmitochondrial stores of saponin-permeabilized Swiss 3T3 cells was inhibited by oryzalin with an IC50 of 34 μM. Oryzalin inhibited colony formation of HT-29 colon carcinoma cells with an IC50 of 8 μM and inhibited the growth of a number of other cancer cell lines and primary human tumors in vitro with IC50 values in the range 3 to 22 μM. A number of oryzalin analogues were studied and an association was found between the ability to inhibit [Ca2+]i signalling and inhibition of the growth of HT-29 human colon cancer cells (P=0.001) and of CCRF-CEM human leukemia cells (P=0.016). Oryzalin at doses up to 600 mg/kg administered orally or subcutaneously daily to mice for 3 to 10 days beginning
a day after tumor inoculation inhibited the growth of murine B16 melanoma by 63% but showed no appreciable activity when administered
subcutaneously or intraperitoneally to mice beginning a number of days after tumor inoculation against a variety of human
tumor xenografts. The peak plasma concentration of oryzalin following repeated subcutaneous administration of oryzalin at
600 mg/kg per day to mice was 37 μM and of its major metabolite N-depropyl oryzalin was 53 μM. Conclusion: It is unlikely that the absence of significant antitumor activity of oryzalin is a result of the inability to achieve adequate
plasma concentrations.
Received: 24 December 1996 / Accepted: 20 March 1997 相似文献
996.
Ron Epelbaum Channa Shalitin Ruth Segal Clari Valansi Ida Arselan David Faraggi Michelle Leviov Menahem Ben-Shahar Nissim Haim 《Pathology oncology research : POR》1998,4(4):271-276
A novel serum 21 kDa haptoglobin-related protein (Hpr) was investigated in patients with malignant lymphoma, to evaluate its
correlation with clinical and histologic features at presentation and its possible role as a tumor marker for patient outcome.
One hundred fifty eight serum samples were taken from 88 patients with non-Hodgkin’s lymphoma (n=58) and Hodgkin’s disease
(n=30) at presentation and in the course of follow-up. Sera from 61 healthy volunteers served as normal controls. Serum Hpr
levels in the lymphoma patients (median 430xl03 u/ml, range 0-4000xl03) were significantly higher than in the control group (median 68xl03 u/ml, range 0-180xl03) (p=0.0001). Higher median Hpr values were detected in patients with advanced disease (p=0.013), “B” symptoms (p=0.029) and
in males (p=0.053). There was also a significant correlation between Hpr and erythrocyte sedimentation rate (p=0.028). Serial
determinations showed a significant decrease of the initial Hpr values obtained after treatment in 41 patients, 38 of whom
achieved complete remission. In the follow-up period additional Hpr measurements were taken from 17 patients. Three of them
eventually relapsed, and showed increased Hpr levels at the time of relapse. Hpr levels remained low in 11 of 14 patients
who maintained complete remission, and increased in three. In conclusion, serum Hpr is a new serum tumor marker of potential
use in the clinical setting of lymphoma.
This work is dedicated to the memory of Dr. Arie H. Bartal, a dedicated oncologist and friend. This work was supported by
Chemotech Thechnologies Ltd., by grant no. 3676 from the Chief Scientist’s Office of the Ministry of Health, Israel, and by
the Fund for Promotion of Research in the Technion. 相似文献
997.
Phthalates rapidly increase production of reactive oxygen species in vivo: role of Kupffer cells 总被引:7,自引:0,他引:7
Rusyn I Kadiiska MB Dikalova A Kono H Yin M Tsuchiya K Mason RP Peters JM Gonzalez FJ Segal BH Holland SM Thurman RG 《Molecular pharmacology》2001,59(4):744-750
The role of oxidants in the mechanism of tumor promotion by peroxisome proliferators remains controversial. The idea that induction of acyl-coenzyme A oxidase leads to increased production of H(2)O(2), which damages DNA, seems unlikely; still, free radicals might be important in signaling in specialized cell types such as Kupffer cells, which produce mitogens. Because hard evidence for increased oxidant production in vivo after treatment with peroxisome proliferators is lacking, the spin-trapping technique and electron spin resonance spectroscopy were used. Rats were given di(2-ethylhexyl) phthalate (DEHP) acutely. The spin trapping agent alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone was also given and bile samples were collected for 4 h. Under these conditions, the intensity of the six-line radical adduct signal increased to a maximum value of 2.5-fold 2 h after administration of DEHP, before peroxisomal oxidases were induced. Furthermore, DEHP given with [(13)C(2)]dimethyl sulfoxide produced a 12-line electron spin resonance spectrum, providing evidence that DEHP stimulates (*)OH radical formation in vivo. Furthermore, when rats were pretreated with dietary glycine, which inactivates Kupffer cells, DEHP did not increase radical signals. Moreover, similar treatments were performed in knockout mice deficient in NADPH oxidase (p47(phox) subunit). Importantly, DEHP increased oxidant production in wild-type but not in NADPH oxidase-deficient mice. These data provide evidence for the hypothesis that the molecular source of free radicals induced by peroxisome proliferators is NADPH oxidase in Kupffer cells. On the contrary, radical adduct formation was not affected in peroxisome proliferator-activated receptor alpha knockout mice. These observations represent the first direct, in vivo evidence that phthalates increase free radicals in liver before peroxisomal oxidases are induced. 相似文献
998.
The metastatic properties of the methylcholanthrene-induced T-10 sarcoma tumor variants which originated in C3H x C57Bl/6 F1 mice are correlated with the relative expression of class I major histocompatibility complex antigens. Both the nonmetastatic and the highly metastatic clones were found to lack the H-2K region-controlled H-2Kb and H-2Kk antigens. However, the nonmetastatic clones express only the H-2Db molecule whereas the metastatic clones express both the H-2Db and the H-2Dk molecules. Transfection of the highly metastatic lines with cloned H-2K genes (Kb, Kk) reduced their tumorigenicity and abolished the formation of metastasis in syngeneic mice, while the transfection of the nonmetastatic lines with cloned H-2Dk genes resulted in shifting the cells to the metastatic phenotype. The present study is aimed to investigate the expression of protooncogenes in the T-10 fibrosarcoma lines that exhibit distinct metastatic properties in correlation with the expressed H-2 antigens. The major oncogene which showed differential expression in the T-10 clones is Ki-ras. The amounts of specific Ki-ras messenger RNA and the Ki-ras Mr 21,000 protein are expressed in elevated levels in the H-2Dk-negative nonmetastatic clones in comparison with a low level of expression in the H-2Dk-positive highly metastatic clones. Expression of H-2K antigens following transfection with cloned H-2K genes had no effect on the expressed Ki-ras oncogene in the T-10 clones. However, transfection of the nonmetastatic cells with the cloned H-2Dk gene resulted in shifting of the cells to a highly metastatic phenotype and in reduction of the expressed c-Ki-ras oncogene. 相似文献
999.
Eric H. Kraut Tom Fleming Mark Segal James A. Neidhart Brent C. Behrens John MacDonald 《Investigational new drugs》1991,9(1):95-96
Summary Twenty-three patients with advanced pancreatic adenocarcinoma were treated with Pibenzimol utilizing a daily intravenous schedule for five days. There were no objective responses seen. The major toxicity was pancreatic with grade 3 hyperglycemia in eleven patients. Pibenzimol is inactive in patients with advanced pancreatic adenocarcinoma.
Address for offprints: Southwest Oncology Group (SWOG-8800), Operations Office, 5430 Fredericksburg Road, Suite #618, San Antonio, Texas 78229-6197, USA 相似文献
1000.
J L Segal M S Pathak J P Hernandez P L Himber S R Brunnemann R S Charter 《Pharmacotherapy》1999,19(6):713-723
STUDY OBJECTIVE: To determine the effects of the long-term administration of 4-aminopyridine (4-AP) on sensorimotor function in humans with long-standing spinal cord injury (SCI). DESIGN: Randomized, open-label, active-treatment control, dosage-blinded study. SETTING: University-affiliated, tertiary-level care, Department of Veterans Affairs Medical Center. PATIENTS: Twenty-one healthy men and women outpatients suffering from traumatic SCI (14 tetraplegic, 7 paraplegic) for 2 years or more. INTERVENTIONS: Dosages of an immediate-release formulation of 4-AP were titrated. At 3 months, 16 subjects were receiving 4-AP 30 mg/day (high dose); 5 subjects were receiving 4-AP 6 mg/day (low dose) and served as an active-treatment control group. MEASUREMENTS AND MAIN RESULTS: Composite motor and sensory scores had statistically significant increases at 3 months. Maximal expiratory pressure, maximal inspiratory pressure, forced vital capacity, and forced expiratory volume in 1 second showed clinically meaningful and/or statistically significant increases among patients receiving 4-AP 30 mg/day. These subjects also had significant decreases in spasticity (modified Ashworth Scale). Serial biochemical profiles and electroencephalographs were unchanged from baseline, and no clinically significant drug toxicity was encountered. CONCLUSIONS: Long-term oral administration of immediate-release 4-AP was associated with improvement in and recovery of sensory and motor function, enhanced pulmonary function, and diminished spasticity in patients with long-standing SCI. 4-Aminopyridine appears to be safe and relatively free from toxicity when administered orally over 3 months. Each patient who received immediate-release 4-AP 30 mg/day showed a response in one or more of the outcome measures. 相似文献