The in vitro inhibitory effects of chrysophanol and physcion on CYP1B1 were explored,utilizing ethoxyresorufin as the substrate.The inhibition kinetics of CYP1B1 by these compounds were assessed with escalating doses ...The in vitro inhibitory effects of chrysophanol and physcion on CYP1B1 were explored,utilizing ethoxyresorufin as the substrate.The inhibition kinetics of CYP1B1 by these compounds were assessed with escalating doses of ethoxyresorufin.Both chrysophanol(IC_(50)(0.47±0.01)μmol·L^(-1))and physcion(IC_(50)(0.35±0.02)μmol·L^(-1))significantly reduce the catalytic efficiency of CYP1B1.The V_(max)and K_(m)values are determined to be(51.9912±10.0547)pmol·μg^(-1)(protein)·min^(-1) and(0.9663±0.2987)nmol·L^(-1)for chrysophanol,and(45.4227±1.9978)pmol·μg^(-1)(protein)·min^(-1) and(0.4367±0.0386)nmol·L^(-1)for physcion,respectively.Kinetic analysis reveals that chrysophanol and physcion exert mixed inhibitory effects on CYP1B1.This mixed inhibition is primarily characterized by the compounds’ability to competitively bind to the active sites of CYP1B1,as well as potentially through non-competitive mechanisms,thereby reducing the enzyme’s catalytic efficiency.Molecular docking studies are conducted to elucidate the interaction between anthraquinone derivatives and CYP1B1,indicating that these compounds may inhibit CYP1B1 activity by binding to their active sites.The demonstrated capacity of chrysophanol and physcion to inhibit CYP1B1 enzymatic function unveils a potential anticancer mechanism,advancing our comprehension of how the structure of anthraquinone derivatives correlates with CYP1B1 inhibition and paving the way for developing innovative cancer treatments.展开更多
Based on current research, the characteristics and action mechanism of biological nitrification inhibitors at home and abroad were reviewed by combining with the latest research progress. The application effects of bi...Based on current research, the characteristics and action mechanism of biological nitrification inhibitors at home and abroad were reviewed by combining with the latest research progress. The application effects of biological nitrification inhibitors on agricultural production were summarized. Research hotspot and achievements of biological nitrification inhibitors at home and abroad were summarized. The research direction in future was forecasted.展开更多
Gastric carcinoids(GCs),which originate from gastric enterochromaffin-like(ECL) mucosal cells and account for 2.4% of all carcinoids,are found increasingly in the course of upper gastrointestinal tract endoscopy.Curre...Gastric carcinoids(GCs),which originate from gastric enterochromaffin-like(ECL) mucosal cells and account for 2.4% of all carcinoids,are found increasingly in the course of upper gastrointestinal tract endoscopy.Current nosography includes those occurring in chronic conditions with hypergastrinemia,as the type 1 associated with chronic atrophic gastritis,and the type 2 associated with Zollinger-Ellison syndrome in multiple endocrine neoplasia type 1,and type 3,which is unrelated to hypergastrinemia and is frequently malignant,with distant metastases.The optimal clinical approach to GCs remains to be elucidated,depending upon type,size and number of carcinoids.While there is agreement concerning the treatment of type 3 carcinoids,for types 1 and 2,current possibilities include simple surveillance,endoscopic polypectomy,surgical excision,associated or not with surgical antrectomy,or total gastrectomy.Moreover,the recent introduction of somatostatin analogues represents a therapeutic option of possibly outstanding relevance.展开更多
Few clinical studies have demonstrated an anti-proliferative activity of somatostatin (SST) analogs in carcinoids. We report the case of a woman with liver metastases of neuroendocrine tumor and no evidence of the pri...Few clinical studies have demonstrated an anti-proliferative activity of somatostatin (SST) analogs in carcinoids. We report the case of a woman with liver metastases of neuroendocrine tumor and no evidence of the primary tumor. The liver metastases were characterized by high proliferation index, immunoreactiviy for somatostatin receptor (SSTR)-l, 2, 3 and 5 and positive octreoscan. Urinary 5-hydroxyindolacetic acid, serum serotonin and chromogranin A were elevated. Slow release lanreotide (SR-LAN) therapy for 3 mo controlled clinical and biochemical signs of carcinoid tumor and caused a clear-cut reduction in the diameter of two liver metastases and disappearance of another lesion, with further reduction after 6 and 18 mo. We demonstrated a clear-cut long-lasting anti-proliferative effect of SR-LAN on liver metastases of occult carcinoid with high proliferation index and immunoreactivity for SSTR-1, 2, 3, and 5. Immunohistochemistry for SSTRs could be a suitable method for the selection of patients with metastatic carcinoid that may benefit from SST analog therapy.展开更多
We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion.Somatostatin immunoneutralization increased both t...We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion.Somatostatin immunoneutralization increased both the total amylase and volume of pancreatic secretion.Cholecystokinin-A receptor antagonism abolished the stimulatory effect of somatostatin immunoneutralization.We conclude that somatostatin tonically inhibits pancreatic secretion in fasted rats via inhibition of the release or action of cholecystokinin.Furthermore,the source of these peptides is likely islet delta cells and intrapancreatic neurons,respectively.展开更多
Objective To evaluate the bioequivalence between recombinant human growth hormone （rhGH） for reconstitution, and two dosages of liquid formulation of rhGH [ （151U） 5mg or （301U） lOmg per 3ml ]. Methods The study...Objective To evaluate the bioequivalence between recombinant human growth hormone （rhGH） for reconstitution, and two dosages of liquid formulation of rhGH [ （151U） 5mg or （301U） lOmg per 3ml ]. Methods The study drugs were tested in a randomized, single-blind and three-period crossover studies in 24 healthy male subjects. The three drugs were administered by subcutaneous injection at a dose of O. 21U/kg body weight. A continuous somatostatin infusion was given in order to suppress the secretion of endogenous GH. The ve- nous blood samples were drawn at different time points to test the serum concentration of GH. The pharmacokinetic parameters were analyzed by statistical methods. Results 90% confidence intervals （CI） of AUC0-24h among three products were all within 80% - 125% interval （ 103. 4% - 116. 5%, 105. 7% - 119. 6% and 91.9% - 103. 7%, respectively）, and the Cls of C,~ among three products were all within 70% - 143% interval （91.9% - 114. 0%, 103. 7% -127. 2% and 81.6% -97. 4%, respectively）. There was no statisitical difference of tmax among all the three products. Conclusion These data demonstrate that there is bioequivalence between rhGH for reconstitution and two liquid formulations of rhGH.展开更多
Malaria is a disease that has drawn worldwide attention due to the alarming rise of mortality rates particularly in third world countries. During the Plasmodium parasite intraerythrocytic life cycle, metabolic process...Malaria is a disease that has drawn worldwide attention due to the alarming rise of mortality rates particularly in third world countries. During the Plasmodium parasite intraerythrocytic life cycle, metabolic processes include the formation of hemozoin or malaria pigment. This pigment functions in the prevention of oxygen radical-mediated damage to the parasite. Drugs targeting hemozoin formation such as chloroquine and amodaquine are effective and are still used, but recently Plasmodium parasites have become resistant to these drugs, especially against chloroquine. In this study we looked at the potential use of two heterocyclic pyrimidine derivatives as anti-malaria drugs; 2,4-Diamino-6-Mercaptopyrimidine （DAMP） and 2-Mercaptopyrimidine （2-MP）. These compounds bear various coordination sites that enable them to react with metal ions to form coordination compounds. We used two methods for testing the inhibition of ferriprotoporphyrin IX （FP） biomineralisation： semi-quantitative microassay used by Deharo, and a quantitative assay used by G. Blaner and M. Akkawi. We report here the finding that （DAMP） has an in vitro inhibitory effect on I%hematin formation at concentrations and magnitude of nearly similar order to that of chloroquine, 2-MP was found to be effective but to a lower degree than DAMP.展开更多
基金Supported by the Heilongjiang Administration of Traditional Chinese Medicine(ZHY2020-078)the Education Department of Heilongjiang Province(SJGY20210830)。
文摘The in vitro inhibitory effects of chrysophanol and physcion on CYP1B1 were explored,utilizing ethoxyresorufin as the substrate.The inhibition kinetics of CYP1B1 by these compounds were assessed with escalating doses of ethoxyresorufin.Both chrysophanol(IC_(50)(0.47±0.01)μmol·L^(-1))and physcion(IC_(50)(0.35±0.02)μmol·L^(-1))significantly reduce the catalytic efficiency of CYP1B1.The V_(max)and K_(m)values are determined to be(51.9912±10.0547)pmol·μg^(-1)(protein)·min^(-1) and(0.9663±0.2987)nmol·L^(-1)for chrysophanol,and(45.4227±1.9978)pmol·μg^(-1)(protein)·min^(-1) and(0.4367±0.0386)nmol·L^(-1)for physcion,respectively.Kinetic analysis reveals that chrysophanol and physcion exert mixed inhibitory effects on CYP1B1.This mixed inhibition is primarily characterized by the compounds’ability to competitively bind to the active sites of CYP1B1,as well as potentially through non-competitive mechanisms,thereby reducing the enzyme’s catalytic efficiency.Molecular docking studies are conducted to elucidate the interaction between anthraquinone derivatives and CYP1B1,indicating that these compounds may inhibit CYP1B1 activity by binding to their active sites.The demonstrated capacity of chrysophanol and physcion to inhibit CYP1B1 enzymatic function unveils a potential anticancer mechanism,advancing our comprehension of how the structure of anthraquinone derivatives correlates with CYP1B1 inhibition and paving the way for developing innovative cancer treatments.
基金Supported by Tibet Natural Science Foundation(ZJ2014068)School-level Key Project of Tibet Vocational Technical College(2012L07)~~
文摘Based on current research, the characteristics and action mechanism of biological nitrification inhibitors at home and abroad were reviewed by combining with the latest research progress. The application effects of biological nitrification inhibitors on agricultural production were summarized. Research hotspot and achievements of biological nitrification inhibitors at home and abroad were summarized. The research direction in future was forecasted.
文摘Gastric carcinoids(GCs),which originate from gastric enterochromaffin-like(ECL) mucosal cells and account for 2.4% of all carcinoids,are found increasingly in the course of upper gastrointestinal tract endoscopy.Current nosography includes those occurring in chronic conditions with hypergastrinemia,as the type 1 associated with chronic atrophic gastritis,and the type 2 associated with Zollinger-Ellison syndrome in multiple endocrine neoplasia type 1,and type 3,which is unrelated to hypergastrinemia and is frequently malignant,with distant metastases.The optimal clinical approach to GCs remains to be elucidated,depending upon type,size and number of carcinoids.While there is agreement concerning the treatment of type 3 carcinoids,for types 1 and 2,current possibilities include simple surveillance,endoscopic polypectomy,surgical excision,associated or not with surgical antrectomy,or total gastrectomy.Moreover,the recent introduction of somatostatin analogues represents a therapeutic option of possibly outstanding relevance.
基金Supported by the Grants From the Italian Ministry of University and Scientific and Technological Research (MIUR 2003069821-001 60%, 2003)
文摘Few clinical studies have demonstrated an anti-proliferative activity of somatostatin (SST) analogs in carcinoids. We report the case of a woman with liver metastases of neuroendocrine tumor and no evidence of the primary tumor. The liver metastases were characterized by high proliferation index, immunoreactiviy for somatostatin receptor (SSTR)-l, 2, 3 and 5 and positive octreoscan. Urinary 5-hydroxyindolacetic acid, serum serotonin and chromogranin A were elevated. Slow release lanreotide (SR-LAN) therapy for 3 mo controlled clinical and biochemical signs of carcinoid tumor and caused a clear-cut reduction in the diameter of two liver metastases and disappearance of another lesion, with further reduction after 6 and 18 mo. We demonstrated a clear-cut long-lasting anti-proliferative effect of SR-LAN on liver metastases of occult carcinoid with high proliferation index and immunoreactivity for SSTR-1, 2, 3, and 5. Immunohistochemistry for SSTRs could be a suitable method for the selection of patients with metastatic carcinoid that may benefit from SST analog therapy.
文摘We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion.Somatostatin immunoneutralization increased both the total amylase and volume of pancreatic secretion.Cholecystokinin-A receptor antagonism abolished the stimulatory effect of somatostatin immunoneutralization.We conclude that somatostatin tonically inhibits pancreatic secretion in fasted rats via inhibition of the release or action of cholecystokinin.Furthermore,the source of these peptides is likely islet delta cells and intrapancreatic neurons,respectively.
文摘Objective To evaluate the bioequivalence between recombinant human growth hormone （rhGH） for reconstitution, and two dosages of liquid formulation of rhGH [ （151U） 5mg or （301U） lOmg per 3ml ]. Methods The study drugs were tested in a randomized, single-blind and three-period crossover studies in 24 healthy male subjects. The three drugs were administered by subcutaneous injection at a dose of O. 21U/kg body weight. A continuous somatostatin infusion was given in order to suppress the secretion of endogenous GH. The ve- nous blood samples were drawn at different time points to test the serum concentration of GH. The pharmacokinetic parameters were analyzed by statistical methods. Results 90% confidence intervals （CI） of AUC0-24h among three products were all within 80% - 125% interval （ 103. 4% - 116. 5%, 105. 7% - 119. 6% and 91.9% - 103. 7%, respectively）, and the Cls of C,~ among three products were all within 70% - 143% interval （91.9% - 114. 0%, 103. 7% -127. 2% and 81.6% -97. 4%, respectively）. There was no statisitical difference of tmax among all the three products. Conclusion These data demonstrate that there is bioequivalence between rhGH for reconstitution and two liquid formulations of rhGH.
文摘Malaria is a disease that has drawn worldwide attention due to the alarming rise of mortality rates particularly in third world countries. During the Plasmodium parasite intraerythrocytic life cycle, metabolic processes include the formation of hemozoin or malaria pigment. This pigment functions in the prevention of oxygen radical-mediated damage to the parasite. Drugs targeting hemozoin formation such as chloroquine and amodaquine are effective and are still used, but recently Plasmodium parasites have become resistant to these drugs, especially against chloroquine. In this study we looked at the potential use of two heterocyclic pyrimidine derivatives as anti-malaria drugs; 2,4-Diamino-6-Mercaptopyrimidine （DAMP） and 2-Mercaptopyrimidine （2-MP）. These compounds bear various coordination sites that enable them to react with metal ions to form coordination compounds. We used two methods for testing the inhibition of ferriprotoporphyrin IX （FP） biomineralisation： semi-quantitative microassay used by Deharo, and a quantitative assay used by G. Blaner and M. Akkawi. We report here the finding that （DAMP） has an in vitro inhibitory effect on I%hematin formation at concentrations and magnitude of nearly similar order to that of chloroquine, 2-MP was found to be effective but to a lower degree than DAMP.
