By solution culture experiment, three wheat genotypes (Ttiticum aestivum L.) and two oilseed rape genotypes (Brassica napus L.) differing in Mn efficiency under Mn-deficient conditions were used to study mechanisms of...By solution culture experiment, three wheat genotypes (Ttiticum aestivum L.) and two oilseed rape genotypes (Brassica napus L.) differing in Mn efficiency under Mn-deficient conditions were used to study mechanisms of the difference in Mn efficiency between wheat and oilseed rape. The results showed that there were significant differences in the abilities of MnIV reduction and acidification in root rhizosphere between the two species. Compared with wheat, oilseed rape had much higher reducing capacity and intensity of rhizosphere acidification under Mn-deficient conditions. Moreover, the higher ratio of functional leaves Mn/old leaves Mn in oilseed rape than in wheat was also an important factor for the different Mn efficiencies between the two species.展开更多
AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was desi...AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was designed as a prospective, randomized and controlled clinical trial. Forty two patients after portal hypertension surgery were randomly assigned into 2 groups: control group (n = 20) and supplemental group (adding Gin and rhGH, n = 22). Every patient received isocaloric and isonitrogenous standard total parenteral nutrition (TPN) starting 3 d after surgery for 7 d. Blood samples were obtained before surgery and at the 3rd and 10th day postoperatively. Host immunity was evaluated by measuring levels of CD4, CD8, CD4/CD8, IgG, IgM and IgA, and the inflammatory responses were determined by assessing IL-2, TNF-α and C-reactive protein (CRP) levels. Intestinal permeability and integrity was evaluated by L/M test and histological examination, respectively. RESULTS: On postoperative d 10, CD4, CD4/CD8, IgG and IL-2 levels in supplemental group were significantly higher than those in control group (33.7±5.5 vs 31.0 ± 5.4, P 〈 0.05, (1.17±0.32 vs 1.05 ± 0.15, P 〈 0.05, 13.94±1.09 vs 12.33±1.33, P 〈 0.05, and 368.12 ± 59.25 vs 318.12 ± 45.65, P 〈 0.05, respectively), whereas the increase in serum TNF-α concentration was significantly reduced (41.02 ± 27.56 vs 160.09 ± 35.17, P 〈 0.05). The increase in L/M ratio was significantly lower in the supplemental group than in the control group (0.0166 ± 0.0017 vs 0.0339 ± 0.0028, P 〈 0.05). Moreover, mucosal integrity in the supplemental group was better than in the control group.CONCLUSION: Postoperative administration of TPN supplemented with Gin and rhGH in patients after portal hypertension surgery improves immune function, modulates inflammatory response, prevents the intestinal mucous membrane from atrophy and preserves intestinal integrity.展开更多
AIM: To investigate the effect of (-)-epigallocatechin-3-gallate (EGCG) on growth of gastric cancer and its possible mechanism. METHODS: Heterotopic tumors were induced by subcutaneously injection of SGC-7901 ce...AIM: To investigate the effect of (-)-epigallocatechin-3-gallate (EGCG) on growth of gastric cancer and its possible mechanism. METHODS: Heterotopic tumors were induced by subcutaneously injection of SGC-7901 cells in nude mice. Tumor growth was measured by calipers in two dimensions. Tumor angiogenesis was determined with tumor microvessel density (MVD) by immunohistology. Vascular endothelial growth factor (VEGF) protein level and activation of signal transducer and activator of transcription 3 (Star3) were examined by Western blotting. VEGF mRNA expression was determined by RT-PCR and VEGF release in tumor culture medium by ELISA. VEGF-induced cell proliferation was studied by MTT assay, cell migration by gelatin modified Boyden chamber (Transwell) and in vitro angiogenesis by endothelial tube formation in Matrigel. RESULTS: Intraperitoneal injection of EGCG inhibited the growth of gastric cancer by 60.4%. MVD in tumor tissues treated with EGCG was markedly reduced. EGCG treatment reduced VEGF protein level in vitro and in vivo. Secretion and mRNA expression of VEGF in tumor cells were also suppressed by EGCG in a dose-dependent manner. This inhibitory effect was associated with reduced activation of Star3, but EGCG treatment did not change the total Star3 expression. EGCG also inhibited VEGF-induced endothelial cell proliferation, migration and tube formation. CONCLUSION: EGCG inhibits the growth of gastric cancer by reducing VEGF production and angiogenesis, and is a promising candidate for anti-angiogenic treatment of gastric cancer.展开更多
Objective. To explore the role of insulin-like growth factor 1 (IGF-1)gene expression abnormality in neurotrophic causes of diabetic peripheral neurophathy.Methods. Diabetes was induced in Sprague Dawley rats by allox...Objective. To explore the role of insulin-like growth factor 1 (IGF-1)gene expression abnormality in neurotrophic causes of diabetic peripheral neurophathy.Methods. Diabetes was induced in Sprague Dawley rats by alloxan. The parameters were measured as follows: IGF-1 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR); IGF-1 peptide by enzyme-linked immunosorbent assay (ELISA); electrophysiological parameters of nerves by evoked electromyogram; morphometric evaluation of sciatic nerves under light microscope and transmission electron microscope.Results. During early diabetic stage, IGF-1 mRNA [(0.430±0.031)vs. (0.370±0.016), P <0.01,(0.430 ± 0.031 ) vs. (0.280 ± 0.010) , P <0.001, respectively], IGF - 1 peptide contents [ (38.44 ± 3.60)ng/mgvs. (30.06±2.41) ng/mg, P <0.01, (38.44±3.6) ng/mgvs. (3.71 +2.70) ng/mg, P <0.001,respectively] in sciatic nerve tissue reduced in diabetic rats with hyperglycemia and varied with severity of diabetic state when compared with non-diabetic control rats, and further gradually down-regulated in the diabetic rats with duration of diabetes [IGF-1 mRNA (0. 320 ± 0. 021) ~ (0. 230 + 0. 060); IGF-1 peptide (28.80 ± 3.30) ~(19. 51 + 1.80)ng/mg]. Furthermore, they correlated with nerve functional (sensory nerve conduction velocity:r = 0. 741, P <0. 001; amplitude ofevokedpotential: r = 0. 716, P <0. 001, respectively)andstructuralabnormality (axonal areas r = 0. 81, P < 0. 001 ) of sciatic nerve. No difference was found in the above parameters between diabetic rats with euglycemia and non-diabetic control group.Conclusion. IGF-1 gene expression in tissues was down-regulated from early diabetic stage, and varied with the severity and duration of diabetic state. The decrement in IGF-1 level might contribute to the initiation and development of diabetic neuropathy via autocrine or paracrine pathway.展开更多
AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-...AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-1 was inoculated subcutaneously into the back of nude mice. When tumor nodules were grown as large as about 5 mmx5 mm days after inoculation, the mice were randomly divided into 3 groups (6 mice in each group). Group Ⅰ served as untreated control group. Group Ⅱ received an intratumoral injection of a combination of human cytomegalovirus promoter-6C (pCMV-6C) and lipofectamine 2000. Group Ⅲ received an intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000. The rate of tumor growth was compared among these three groups. The expression of SSTR2 in these tumors was detected by immunohistochemistry and Western-blot. Apoptosis index (AI) in these tumors was examined by using TUNEL in situ. RESULTS: Intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000 resulted in the expression of SSTR2 protein. The tumor size and weight in group Ⅲ (0.318±0.098 cm3, and 0.523±0.090 g, respectively) were significantly lower than those in group I (2.058±0.176 cms, and 1.412±0.146 g, respectively) and group Ⅱ (2.025±0.163 cm3, and 1.365±0.116 g, respectively) (P<0.05) The AI in group Ⅲ (1.47±0.13%) was significantly higher than that in groupⅠ(0.56±0.09%) and group Ⅱ (0.57±0.11%) (P<0.05). But there were no significant differences between groups Ⅰ and Ⅱ. CONCLUSION: Our data demonstrate that re-expression of SSTR2 gene has antitumor effects on experimental pancreatic cancer. Restoration of SSTR2 gene expression through gene transfer in vivo might be a potential gene therapy strategy for human pancreatic cancer.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
Hexarelin, a synthetic growth hormone-releasing peptide, can bind to and activate the growth hormone secretagogue receptor (GHSR) in the brain similar to its natural analog ghrelin. However, the peripheral distribut...Hexarelin, a synthetic growth hormone-releasing peptide, can bind to and activate the growth hormone secretagogue receptor (GHSR) in the brain similar to its natural analog ghrelin. However, the peripheral distribution of GHSR in the heart and blood vessels suggests that hexarelin might have direct cardiovascular actions beyond growth hormone release and neuroendocrine effects. Furthermore, the non-GHSR CD36 had been demonstrated to be a specific cardiac receptor for hexarelin and to mediate its cardioprotective effects. When compared with ghrelin, hexarelin is chemically more stable and functionally more potent. Therefore, it may be a promising therapeutic agent for some car-diovascular conditions. In this concise review, we discuss the current evidence for the cardiovascular action of hexarelin.展开更多
Objective To investigate the relationship between expression of somatostatin receptors(SSTRs) and activation of rat hepatic stellate cell (HSC). Methods HSCs were isolated from rats by in situ perfusion and single-ste...Objective To investigate the relationship between expression of somatostatin receptors(SSTRs) and activation of rat hepatic stellate cell (HSC). Methods HSCs were isolated from rats by in situ perfusion and single-step density gradient centrifugation, and then SSTR1-5 mRNA levels in the differentiated first passage HSCs were detected by means of reverse transcription polymerase chain reaction. On the other hand, hepatic fibrosis was induced in adult male Sprague-Dawley rats by carbon tetrachloride intoxication, and the expression of SSTR1-5 in normal as well as fibrotic liver was measured by immunohistochemical staining. Results SSTR mR-NA and SSTR could not be found in freshly isolated rat HSCs and normal rat liver. But SSTR1-3 mRNA appeared as HSCs became wholly activated, and SSTR1-3 could also be identified on the membrane of activated HSCs in the peri-sinusoid space, fibrous septa, etc. Conclusion The expression of SSTR1-3 in the rat HSC is closely related to its activation. This may reflect one of the main negative regulation mechanisms in the course of HSC activation.展开更多
H. suaveolens (L.) Poit has been used in folk medicine revealing a wide pharmacological potential. This study aimed to evaluate the efficacy of the essential oil from 11. suaveolens leaves in inhibiting the growth o...H. suaveolens (L.) Poit has been used in folk medicine revealing a wide pharmacological potential. This study aimed to evaluate the efficacy of the essential oil from 11. suaveolens leaves in inhibiting the growth of A. flavus LM257 and synthesis of aflatoxins Bl and B2. The essential oil at 20, 40 and 80 laL/mL strongly reduced the biomass and spore germination ofA. flavus. A 100% inhibition was found at 40 μL/mL and 80μL/mL, while at 20 μL/mL the growth depressed over 50% for both tested parameters. The essential oil at all assayed concentrations totally inhibited the production of aflatoxin B1 and B2. From these results, the essential oil from 11. suaveolens leaves may be considered as an alternative and effective inhibitor ofA. flavus, in addition to offer some protective effect to the production of aflatoxins.展开更多
基金Project (No. 39425013) supported by the National Natural Science Foundation of China.
文摘By solution culture experiment, three wheat genotypes (Ttiticum aestivum L.) and two oilseed rape genotypes (Brassica napus L.) differing in Mn efficiency under Mn-deficient conditions were used to study mechanisms of the difference in Mn efficiency between wheat and oilseed rape. The results showed that there were significant differences in the abilities of MnIV reduction and acidification in root rhizosphere between the two species. Compared with wheat, oilseed rape had much higher reducing capacity and intensity of rhizosphere acidification under Mn-deficient conditions. Moreover, the higher ratio of functional leaves Mn/old leaves Mn in oilseed rape than in wheat was also an important factor for the different Mn efficiencies between the two species.
文摘AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was designed as a prospective, randomized and controlled clinical trial. Forty two patients after portal hypertension surgery were randomly assigned into 2 groups: control group (n = 20) and supplemental group (adding Gin and rhGH, n = 22). Every patient received isocaloric and isonitrogenous standard total parenteral nutrition (TPN) starting 3 d after surgery for 7 d. Blood samples were obtained before surgery and at the 3rd and 10th day postoperatively. Host immunity was evaluated by measuring levels of CD4, CD8, CD4/CD8, IgG, IgM and IgA, and the inflammatory responses were determined by assessing IL-2, TNF-α and C-reactive protein (CRP) levels. Intestinal permeability and integrity was evaluated by L/M test and histological examination, respectively. RESULTS: On postoperative d 10, CD4, CD4/CD8, IgG and IL-2 levels in supplemental group were significantly higher than those in control group (33.7±5.5 vs 31.0 ± 5.4, P 〈 0.05, (1.17±0.32 vs 1.05 ± 0.15, P 〈 0.05, 13.94±1.09 vs 12.33±1.33, P 〈 0.05, and 368.12 ± 59.25 vs 318.12 ± 45.65, P 〈 0.05, respectively), whereas the increase in serum TNF-α concentration was significantly reduced (41.02 ± 27.56 vs 160.09 ± 35.17, P 〈 0.05). The increase in L/M ratio was significantly lower in the supplemental group than in the control group (0.0166 ± 0.0017 vs 0.0339 ± 0.0028, P 〈 0.05). Moreover, mucosal integrity in the supplemental group was better than in the control group.CONCLUSION: Postoperative administration of TPN supplemented with Gin and rhGH in patients after portal hypertension surgery improves immune function, modulates inflammatory response, prevents the intestinal mucous membrane from atrophy and preserves intestinal integrity.
基金Supported by the grants from the National Natural Science Foundation of China, No. 30571833the Natural Science Foundation of Guangdong Province, China, No. 05001785
文摘AIM: To investigate the effect of (-)-epigallocatechin-3-gallate (EGCG) on growth of gastric cancer and its possible mechanism. METHODS: Heterotopic tumors were induced by subcutaneously injection of SGC-7901 cells in nude mice. Tumor growth was measured by calipers in two dimensions. Tumor angiogenesis was determined with tumor microvessel density (MVD) by immunohistology. Vascular endothelial growth factor (VEGF) protein level and activation of signal transducer and activator of transcription 3 (Star3) were examined by Western blotting. VEGF mRNA expression was determined by RT-PCR and VEGF release in tumor culture medium by ELISA. VEGF-induced cell proliferation was studied by MTT assay, cell migration by gelatin modified Boyden chamber (Transwell) and in vitro angiogenesis by endothelial tube formation in Matrigel. RESULTS: Intraperitoneal injection of EGCG inhibited the growth of gastric cancer by 60.4%. MVD in tumor tissues treated with EGCG was markedly reduced. EGCG treatment reduced VEGF protein level in vitro and in vivo. Secretion and mRNA expression of VEGF in tumor cells were also suppressed by EGCG in a dose-dependent manner. This inhibitory effect was associated with reduced activation of Star3, but EGCG treatment did not change the total Star3 expression. EGCG also inhibited VEGF-induced endothelial cell proliferation, migration and tube formation. CONCLUSION: EGCG inhibits the growth of gastric cancer by reducing VEGF production and angiogenesis, and is a promising candidate for anti-angiogenic treatment of gastric cancer.
基金This work was supported by the National Natural Sciences Foun-dation of China.This work was originally published in Chinese Journal of Internal Medicine (2001 40(2): 93-7)in Chinese.
文摘Objective. To explore the role of insulin-like growth factor 1 (IGF-1)gene expression abnormality in neurotrophic causes of diabetic peripheral neurophathy.Methods. Diabetes was induced in Sprague Dawley rats by alloxan. The parameters were measured as follows: IGF-1 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR); IGF-1 peptide by enzyme-linked immunosorbent assay (ELISA); electrophysiological parameters of nerves by evoked electromyogram; morphometric evaluation of sciatic nerves under light microscope and transmission electron microscope.Results. During early diabetic stage, IGF-1 mRNA [(0.430±0.031)vs. (0.370±0.016), P <0.01,(0.430 ± 0.031 ) vs. (0.280 ± 0.010) , P <0.001, respectively], IGF - 1 peptide contents [ (38.44 ± 3.60)ng/mgvs. (30.06±2.41) ng/mg, P <0.01, (38.44±3.6) ng/mgvs. (3.71 +2.70) ng/mg, P <0.001,respectively] in sciatic nerve tissue reduced in diabetic rats with hyperglycemia and varied with severity of diabetic state when compared with non-diabetic control rats, and further gradually down-regulated in the diabetic rats with duration of diabetes [IGF-1 mRNA (0. 320 ± 0. 021) ~ (0. 230 + 0. 060); IGF-1 peptide (28.80 ± 3.30) ~(19. 51 + 1.80)ng/mg]. Furthermore, they correlated with nerve functional (sensory nerve conduction velocity:r = 0. 741, P <0. 001; amplitude ofevokedpotential: r = 0. 716, P <0. 001, respectively)andstructuralabnormality (axonal areas r = 0. 81, P < 0. 001 ) of sciatic nerve. No difference was found in the above parameters between diabetic rats with euglycemia and non-diabetic control group.Conclusion. IGF-1 gene expression in tissues was down-regulated from early diabetic stage, and varied with the severity and duration of diabetic state. The decrement in IGF-1 level might contribute to the initiation and development of diabetic neuropathy via autocrine or paracrine pathway.
基金Supported by National Natural Science Foundation of China, No. 30271473
文摘AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-1 was inoculated subcutaneously into the back of nude mice. When tumor nodules were grown as large as about 5 mmx5 mm days after inoculation, the mice were randomly divided into 3 groups (6 mice in each group). Group Ⅰ served as untreated control group. Group Ⅱ received an intratumoral injection of a combination of human cytomegalovirus promoter-6C (pCMV-6C) and lipofectamine 2000. Group Ⅲ received an intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000. The rate of tumor growth was compared among these three groups. The expression of SSTR2 in these tumors was detected by immunohistochemistry and Western-blot. Apoptosis index (AI) in these tumors was examined by using TUNEL in situ. RESULTS: Intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000 resulted in the expression of SSTR2 protein. The tumor size and weight in group Ⅲ (0.318±0.098 cm3, and 0.523±0.090 g, respectively) were significantly lower than those in group I (2.058±0.176 cms, and 1.412±0.146 g, respectively) and group Ⅱ (2.025±0.163 cm3, and 1.365±0.116 g, respectively) (P<0.05) The AI in group Ⅲ (1.47±0.13%) was significantly higher than that in groupⅠ(0.56±0.09%) and group Ⅱ (0.57±0.11%) (P<0.05). But there were no significant differences between groups Ⅰ and Ⅱ. CONCLUSION: Our data demonstrate that re-expression of SSTR2 gene has antitumor effects on experimental pancreatic cancer. Restoration of SSTR2 gene expression through gene transfer in vivo might be a potential gene therapy strategy for human pancreatic cancer.
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Hexarelin, a synthetic growth hormone-releasing peptide, can bind to and activate the growth hormone secretagogue receptor (GHSR) in the brain similar to its natural analog ghrelin. However, the peripheral distribution of GHSR in the heart and blood vessels suggests that hexarelin might have direct cardiovascular actions beyond growth hormone release and neuroendocrine effects. Furthermore, the non-GHSR CD36 had been demonstrated to be a specific cardiac receptor for hexarelin and to mediate its cardioprotective effects. When compared with ghrelin, hexarelin is chemically more stable and functionally more potent. Therefore, it may be a promising therapeutic agent for some car-diovascular conditions. In this concise review, we discuss the current evidence for the cardiovascular action of hexarelin.
基金Supported by the Scientific Development Programs of Science and Technology Commission Foundation of Shanghai (004119047).
文摘Objective To investigate the relationship between expression of somatostatin receptors(SSTRs) and activation of rat hepatic stellate cell (HSC). Methods HSCs were isolated from rats by in situ perfusion and single-step density gradient centrifugation, and then SSTR1-5 mRNA levels in the differentiated first passage HSCs were detected by means of reverse transcription polymerase chain reaction. On the other hand, hepatic fibrosis was induced in adult male Sprague-Dawley rats by carbon tetrachloride intoxication, and the expression of SSTR1-5 in normal as well as fibrotic liver was measured by immunohistochemical staining. Results SSTR mR-NA and SSTR could not be found in freshly isolated rat HSCs and normal rat liver. But SSTR1-3 mRNA appeared as HSCs became wholly activated, and SSTR1-3 could also be identified on the membrane of activated HSCs in the peri-sinusoid space, fibrous septa, etc. Conclusion The expression of SSTR1-3 in the rat HSC is closely related to its activation. This may reflect one of the main negative regulation mechanisms in the course of HSC activation.
文摘H. suaveolens (L.) Poit has been used in folk medicine revealing a wide pharmacological potential. This study aimed to evaluate the efficacy of the essential oil from 11. suaveolens leaves in inhibiting the growth of A. flavus LM257 and synthesis of aflatoxins Bl and B2. The essential oil at 20, 40 and 80 laL/mL strongly reduced the biomass and spore germination ofA. flavus. A 100% inhibition was found at 40 μL/mL and 80μL/mL, while at 20 μL/mL the growth depressed over 50% for both tested parameters. The essential oil at all assayed concentrations totally inhibited the production of aflatoxin B1 and B2. From these results, the essential oil from 11. suaveolens leaves may be considered as an alternative and effective inhibitor ofA. flavus, in addition to offer some protective effect to the production of aflatoxins.