Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil （5-FU） in patients with advanced breast cancer. Methods Twenty...Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil （5-FU） in patients with advanced breast cancer. Methods Twenty-seven patients with breast cancer received repeated doses of 1 255 mg·m^-2 of capecitabine twice daily for 7 d. Blood, tumor, and adjacent healthy tissue samples were collected. The concentrations of capecitabine and its metabolite 5-FU were determined by HPLC. The concentration-time profiles of capecitabine and 5-FU were fitted by pharmacokinetic model. The tissue distribution factors for capecitabine and 5-FU, and the AUC ratios of 5-FU to capecitabine in plasma, tumor or adjacent healthy tissue, were calculated with pharmacokinetic parameters, respectively. Results The Ka of capecitabine was 1.17 h^-1 in plasma, 0. 46 h^-1 in tumor tissue, and 0. 61 h^-1 in healthy tissue. The AUCs of capecitabine were 2. 557 1 μg·mL^-1 ·h, 1. 629 2 μg·g^-1·h and 2. 085 0 μg·g^-1· h, and T1/2 was 0. 782 3 h, 1. 528 1 h and 1. 289 6 h in plasma, tumor, and healthy tissue, respectively. The AUCs of 5-FU were 0.418 7 μg·mL^-1 h, 1.671 7 μg·g^-1·h and 1.020 8 μg·g^-1·h; the T1/2 was 0. 631 3 h ,1.204 1 h and 1.031 2 h in plasma, tumor, and healthy tissue, respectively. The tissue distribution factors of capecitabine were 0. 637 1 in tumor （AUCcap-Tumor/AUCcap-plasma） and 0. 851 4 in healthy tissue （AUCcap-HT/AUCcap-plasma . The tissue distribution factors of 5-FU were 3. 992 6 in tumor （AUC5-FU-Tumor/AUC5-FU-plasma） and 2. 438 0 in healthy tissue （AUC5-FU-HT/AUC5-FU-plasma）. The AUC ratios of 5-FU to capecitabine were 0. 1637, 1. 0261, and 0. 489 5 in plasma, tumor, and healthy tissue, respectively. Conclusion The simulation curves for the disposition of capecitabine and its metabolite 5-FU in plasma and tissue basically describe the activation process of capecitabine metabolizing to 5-FU and 5-FU elimination. There are similar distributions for capecitabine in plasma, tumor, and healthy tissue. The exposure of 5-FU in tumor was found to be 3. 992 6 times greater than that in plasma and 2. 438 0 times greater than that in healthy tissue. Capecitabine may metabolize preferentially to 5- FU in tumor tissue after oral administration.展开更多
The purpose of this study is to characterize the tissue distribution, excretion and pharmacokinetics profiles of R-hap in healthy Wistar rats. R-hap was radiolabeled by the IODO-GEN method. Tissue distribution and uri...The purpose of this study is to characterize the tissue distribution, excretion and pharmacokinetics profiles of R-hap in healthy Wistar rats. R-hap was radiolabeled by the IODO-GEN method. Tissue distribution and urinary, fecal and biliary excretion patterns of ^125I-R-hap were investigated following a single i.v. bolus injection. Pharmacokinetics properties of ^125I-R-hap were also examined after a single i.v. bolus injection. The trichloroacetic acid （TCA） precipitated radioactivity was widely distributed and rapiclly diminished in most tissues. Kidney contained the highest radioactivity among all organs and the distribution of ^125I-R-hap to fat was minimal. The cumulative excretion of ^125I-R-hap reached 71.81% ± 2.15% of the administered radioactivity at 48 h and 94.71% ± 1.50% at 120 h. Urinary excretion was the dominant route of elimination following i.v. administration, as 80.64% ± 1.47% and 14.07% ± 0.95% of administered radioactivity were recovered in urine and feces, respectively, in intact rats over 120 h. The mean areas under the plasma concentration-time curve was （8818.4 ± 576.1） Bq/h/mL. The results of tissue distribution, excretion and pharmacokinetics of R-hap in rats provided biopharmaceutical basis for the design of future clinical trials.展开更多
AIM： To study the expression of trefoil factor 1 （TFF1） and TFF2 in precancerous condition and gastric cancer and to explore the relationship between TFFs and tumorigenesis, precancerous condition and gastric cance...AIM： To study the expression of trefoil factor 1 （TFF1） and TFF2 in precancerous condition and gastric cancer and to explore the relationship between TFFs and tumorigenesis, precancerous condition and gastric cancer. METHODS： The expression of TFF1 and TFF2 was immunohistochemically analyzed in paraffin-embedded samples from 140 patients including 35 cases of chronic superficial gastritis （CSG）, 35 cases of gastric ulcer （GU）, 35 cases of chronic atrophic gastritis （CAG） and 35 cases of gastric cancer （GC）. RESULTS： TFF1 and TFF2 were located in cytoplasm of gastric mucous cells. In CSG, GU, CAG and GC, the level of TFF1 expression had a decreased tendency （P〈 0.05）. The expression of TFF2 was higher in GU than in CSG, but the difference was not significant. The expression of TFF2 also had a decreased tendency in GU, CAG, and GC （P〈 0.05）. CONCLUSION： The reduced expression of TFF1 and TFF2 in precancerous conditions and gastric cancer may be associated with the proliferation and malignant transformation of gastric mucosa. More investigations are needed to explore the mechanism of TFFs and the relationship between TFFs and gastric cancer.展开更多
文摘Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil （5-FU） in patients with advanced breast cancer. Methods Twenty-seven patients with breast cancer received repeated doses of 1 255 mg·m^-2 of capecitabine twice daily for 7 d. Blood, tumor, and adjacent healthy tissue samples were collected. The concentrations of capecitabine and its metabolite 5-FU were determined by HPLC. The concentration-time profiles of capecitabine and 5-FU were fitted by pharmacokinetic model. The tissue distribution factors for capecitabine and 5-FU, and the AUC ratios of 5-FU to capecitabine in plasma, tumor or adjacent healthy tissue, were calculated with pharmacokinetic parameters, respectively. Results The Ka of capecitabine was 1.17 h^-1 in plasma, 0. 46 h^-1 in tumor tissue, and 0. 61 h^-1 in healthy tissue. The AUCs of capecitabine were 2. 557 1 μg·mL^-1 ·h, 1. 629 2 μg·g^-1·h and 2. 085 0 μg·g^-1· h, and T1/2 was 0. 782 3 h, 1. 528 1 h and 1. 289 6 h in plasma, tumor, and healthy tissue, respectively. The AUCs of 5-FU were 0.418 7 μg·mL^-1 h, 1.671 7 μg·g^-1·h and 1.020 8 μg·g^-1·h; the T1/2 was 0. 631 3 h ,1.204 1 h and 1.031 2 h in plasma, tumor, and healthy tissue, respectively. The tissue distribution factors of capecitabine were 0. 637 1 in tumor （AUCcap-Tumor/AUCcap-plasma） and 0. 851 4 in healthy tissue （AUCcap-HT/AUCcap-plasma . The tissue distribution factors of 5-FU were 3. 992 6 in tumor （AUC5-FU-Tumor/AUC5-FU-plasma） and 2. 438 0 in healthy tissue （AUC5-FU-HT/AUC5-FU-plasma）. The AUC ratios of 5-FU to capecitabine were 0. 1637, 1. 0261, and 0. 489 5 in plasma, tumor, and healthy tissue, respectively. Conclusion The simulation curves for the disposition of capecitabine and its metabolite 5-FU in plasma and tissue basically describe the activation process of capecitabine metabolizing to 5-FU and 5-FU elimination. There are similar distributions for capecitabine in plasma, tumor, and healthy tissue. The exposure of 5-FU in tumor was found to be 3. 992 6 times greater than that in plasma and 2. 438 0 times greater than that in healthy tissue. Capecitabine may metabolize preferentially to 5- FU in tumor tissue after oral administration.
基金National Natural Sciences Foundation of China(Grant No.30371669)National High Technology Research and Development Program of China(863 Program,Grant No.2003AA2Z347B).
文摘The purpose of this study is to characterize the tissue distribution, excretion and pharmacokinetics profiles of R-hap in healthy Wistar rats. R-hap was radiolabeled by the IODO-GEN method. Tissue distribution and urinary, fecal and biliary excretion patterns of ^125I-R-hap were investigated following a single i.v. bolus injection. Pharmacokinetics properties of ^125I-R-hap were also examined after a single i.v. bolus injection. The trichloroacetic acid （TCA） precipitated radioactivity was widely distributed and rapiclly diminished in most tissues. Kidney contained the highest radioactivity among all organs and the distribution of ^125I-R-hap to fat was minimal. The cumulative excretion of ^125I-R-hap reached 71.81% ± 2.15% of the administered radioactivity at 48 h and 94.71% ± 1.50% at 120 h. Urinary excretion was the dominant route of elimination following i.v. administration, as 80.64% ± 1.47% and 14.07% ± 0.95% of administered radioactivity were recovered in urine and feces, respectively, in intact rats over 120 h. The mean areas under the plasma concentration-time curve was （8818.4 ± 576.1） Bq/h/mL. The results of tissue distribution, excretion and pharmacokinetics of R-hap in rats provided biopharmaceutical basis for the design of future clinical trials.
文摘AIM： To study the expression of trefoil factor 1 （TFF1） and TFF2 in precancerous condition and gastric cancer and to explore the relationship between TFFs and tumorigenesis, precancerous condition and gastric cancer. METHODS： The expression of TFF1 and TFF2 was immunohistochemically analyzed in paraffin-embedded samples from 140 patients including 35 cases of chronic superficial gastritis （CSG）, 35 cases of gastric ulcer （GU）, 35 cases of chronic atrophic gastritis （CAG） and 35 cases of gastric cancer （GC）. RESULTS： TFF1 and TFF2 were located in cytoplasm of gastric mucous cells. In CSG, GU, CAG and GC, the level of TFF1 expression had a decreased tendency （P〈 0.05）. The expression of TFF2 was higher in GU than in CSG, but the difference was not significant. The expression of TFF2 also had a decreased tendency in GU, CAG, and GC （P〈 0.05）. CONCLUSION： The reduced expression of TFF1 and TFF2 in precancerous conditions and gastric cancer may be associated with the proliferation and malignant transformation of gastric mucosa. More investigations are needed to explore the mechanism of TFFs and the relationship between TFFs and gastric cancer.
