OVER 2,000 years ago,silk was the symblol of China;1,000 ago,porcelain was the symblol of China;500 years ago,tea was the symblol of China;today,with human beings’increasing awarness in ecological preservation,the gi...OVER 2,000 years ago,silk was the symblol of China;1,000 ago,porcelain was the symblol of China;500 years ago,tea was the symblol of China;today,with human beings’increasing awarness in ecological preservation,the giant panda has become a symblol of China.In 1869,the French naturalist Armand David discovered the giant panda in Ya’an,and since then,the flagship species of biodiversity conservation has since stepped onto the world stage.展开更多
Glucagon is a potent glucose-elevating hormone that is secreted by pancreaticα-cells.While well-controlled glucagon secretion plays an important role in maintaining systemic glucose homeostasis and preventing hypogly...Glucagon is a potent glucose-elevating hormone that is secreted by pancreaticα-cells.While well-controlled glucagon secretion plays an important role in maintaining systemic glucose homeostasis and preventing hypoglycaemia,it is increasingly apparent that defects in the regulation of glucagon secretion contribute to impaired counter-regulation and hyperglycaemia in diabetes.It has therefore been proposed that pharmacological interventions targeting glucagon secretion/signalling can have great potential in improving glycaemic control of patients with diabetes.However,despite decades of research,a consensus on the precise mechanisms of glucose regulation of glucagon secretion is yet to be reached.Second messengers are a group of small intracellular molecules that relay extracellular signals to the intracellular signalling cascade,modulating cellular functions.There is a growing body of evidence that second messengers,such as cAMP and Ca^(2+),play critical roles inα-cell glucose-sensing and glucagon secretion.In this review,we discuss the impact of second messengers onα-cell electrical activity,intracellular Ca^(2+)dynamics and cell exocytosis.We highlight the possibility that the interaction between different second messengers may play a key role in the glucose-regulation of glucagon secretion.展开更多
Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments.Current un...Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments.Current understanding of reconnection phenomena at Mercury is rooted in the MESSENGER mission.However,direct detection of reconnection remains rare.Here,we aim to assess the limitations of MESSENGER in detecting reconnection in Mercury’s space and to discuss key issues of reconnection that will be addressed by BepiColombo,including the dynamics of magnetic flux ropes,particle acceleration,density asymmetric reconnection,IMF-driven near-tail structures,and potential modes of magnetospheric convection.展开更多
Objective: To study the multidrug resistance (MDR) mechanism of lung resistance protein (LRP) gene in hepatocellular carcinoma (HCC), and the relations among the expression of the LRP gene and clinicopathologic featur...Objective: To study the multidrug resistance (MDR) mechanism of lung resistance protein (LRP) gene in hepatocellular carcinoma (HCC), and the relations among the expression of the LRP gene and clinicopathologic features, the influence of α-fetoprotein (AFP), and prognosis of patients who received adjuvant chemotherapy after resection of HCC. Methods: The expression of the LRP gene encoding LRP and mRNA LRP was detected in tissues from 54 untreated patients with HCC, adjacent tissues from 24 patients with HCC and archival paraffin-embedded tissues from 12 patients with posthepatitic cirrhosis. The relationship between the LRP gene expression and the change of AFP level was analyzed in the 24 postoperative HCC patients whose AFP was measured after 2 weeks. All of the HCC patients were followed up. Results: The percentage of positive expression of LRP and mRNA LRP in the 3 tissues was 61.1%, 33.3%, 16.7%, and 75.9%, 37.5%, 33.3% respectively. There was significant difference between the untreated HCC tissue and other tissues (P<0.05). No difference existed between the LRP gene expression and clinicopathologic findings, age, sex, and tumor size (P>0.05), but the expression was related to the degree of differentiation of HCC (P<0.05). The effective rate of AFP in the LRP gene positive expression group or in postoperative chemotherapeutic patients was very lower than that in the negative group (P<0.05). Although the mean survival time of postoperative HCC patients in negative LRP gene expression group was longer than that of positive group, there was no difference between them (P<0.05). Conclusion: LRP gene expression is related to MDR of HCC and initiates the intrinsic MDR. Detection of LRP gene expression is of great guiding significance in accessing chemotherapeutic resistance of HCC. As an index to chemotherapy of HCC, detection of LRP expression provides evidence for making individual chemotherapeutic treatment,and reversing MDR in HCC. Although LRP gene expression correlates with the tumor differential degree (P<0.05), it perhaps does not relate with the prognosis of HCC patients.展开更多
Today there is significant information indicating an effect of prolactin on the prostate gland. It has been shown to be involved in mechanisms leading to the synthesis of some proteins such as PSA and cathepsin D, syn...Today there is significant information indicating an effect of prolactin on the prostate gland. It has been shown to be involved in mechanisms leading to the synthesis of some proteins such as PSA and cathepsin D, synthesis of citrate and accumulation of zinc. Also, at the behavioral level, prolactin is known to control some aspects of reproduction, including documentation on the physiology of the prostate and the possibility to trigger pathologies in this sex gland. Although the later still is not clear, there is a correlation between the level of prolactin and the presence of prostate pathologies. Thus, the aim of this review is to show how prolactin is involved in the progression of some pathologies of this male sexual gland.展开更多
文摘OVER 2,000 years ago,silk was the symblol of China;1,000 ago,porcelain was the symblol of China;500 years ago,tea was the symblol of China;today,with human beings’increasing awarness in ecological preservation,the giant panda has become a symblol of China.In 1869,the French naturalist Armand David discovered the giant panda in Ya’an,and since then,the flagship species of biodiversity conservation has since stepped onto the world stage.
基金EFSD European Research Programme on New Targets for Type 2 Diabetes(Grant/Award Number:96406)Diabetes UK RD Lawrence Fellowship(Grant/Award Number:14/0005128)。
文摘Glucagon is a potent glucose-elevating hormone that is secreted by pancreaticα-cells.While well-controlled glucagon secretion plays an important role in maintaining systemic glucose homeostasis and preventing hypoglycaemia,it is increasingly apparent that defects in the regulation of glucagon secretion contribute to impaired counter-regulation and hyperglycaemia in diabetes.It has therefore been proposed that pharmacological interventions targeting glucagon secretion/signalling can have great potential in improving glycaemic control of patients with diabetes.However,despite decades of research,a consensus on the precise mechanisms of glucose regulation of glucagon secretion is yet to be reached.Second messengers are a group of small intracellular molecules that relay extracellular signals to the intracellular signalling cascade,modulating cellular functions.There is a growing body of evidence that second messengers,such as cAMP and Ca^(2+),play critical roles inα-cell glucose-sensing and glucagon secretion.In this review,we discuss the impact of second messengers onα-cell electrical activity,intracellular Ca^(2+)dynamics and cell exocytosis.We highlight the possibility that the interaction between different second messengers may play a key role in the glucose-regulation of glucagon secretion.
基金supported by the National Natural Science Foundation of China(42174217).
文摘Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments.Current understanding of reconnection phenomena at Mercury is rooted in the MESSENGER mission.However,direct detection of reconnection remains rare.Here,we aim to assess the limitations of MESSENGER in detecting reconnection in Mercury’s space and to discuss key issues of reconnection that will be addressed by BepiColombo,including the dynamics of magnetic flux ropes,particle acceleration,density asymmetric reconnection,IMF-driven near-tail structures,and potential modes of magnetospheric convection.
文摘Objective: To study the multidrug resistance (MDR) mechanism of lung resistance protein (LRP) gene in hepatocellular carcinoma (HCC), and the relations among the expression of the LRP gene and clinicopathologic features, the influence of α-fetoprotein (AFP), and prognosis of patients who received adjuvant chemotherapy after resection of HCC. Methods: The expression of the LRP gene encoding LRP and mRNA LRP was detected in tissues from 54 untreated patients with HCC, adjacent tissues from 24 patients with HCC and archival paraffin-embedded tissues from 12 patients with posthepatitic cirrhosis. The relationship between the LRP gene expression and the change of AFP level was analyzed in the 24 postoperative HCC patients whose AFP was measured after 2 weeks. All of the HCC patients were followed up. Results: The percentage of positive expression of LRP and mRNA LRP in the 3 tissues was 61.1%, 33.3%, 16.7%, and 75.9%, 37.5%, 33.3% respectively. There was significant difference between the untreated HCC tissue and other tissues (P<0.05). No difference existed between the LRP gene expression and clinicopathologic findings, age, sex, and tumor size (P>0.05), but the expression was related to the degree of differentiation of HCC (P<0.05). The effective rate of AFP in the LRP gene positive expression group or in postoperative chemotherapeutic patients was very lower than that in the negative group (P<0.05). Although the mean survival time of postoperative HCC patients in negative LRP gene expression group was longer than that of positive group, there was no difference between them (P<0.05). Conclusion: LRP gene expression is related to MDR of HCC and initiates the intrinsic MDR. Detection of LRP gene expression is of great guiding significance in accessing chemotherapeutic resistance of HCC. As an index to chemotherapy of HCC, detection of LRP expression provides evidence for making individual chemotherapeutic treatment,and reversing MDR in HCC. Although LRP gene expression correlates with the tumor differential degree (P<0.05), it perhaps does not relate with the prognosis of HCC patients.
文摘Today there is significant information indicating an effect of prolactin on the prostate gland. It has been shown to be involved in mechanisms leading to the synthesis of some proteins such as PSA and cathepsin D, synthesis of citrate and accumulation of zinc. Also, at the behavioral level, prolactin is known to control some aspects of reproduction, including documentation on the physiology of the prostate and the possibility to trigger pathologies in this sex gland. Although the later still is not clear, there is a correlation between the level of prolactin and the presence of prostate pathologies. Thus, the aim of this review is to show how prolactin is involved in the progression of some pathologies of this male sexual gland.
