Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to un...Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to undergo a step-wise oscillation. The hierarchic structures composed of both large and small domains were obtained. The mechanism of the periodic formation of hierarchic structures was also demonstrated.展开更多
The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed ...The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods.展开更多
In any multi-cellular organism, the balance between cell division and cell death maintains a constant cell number. Both cell division cycle and cell death are highly regulated events. Whether the cell will proceed thr...In any multi-cellular organism, the balance between cell division and cell death maintains a constant cell number. Both cell division cycle and cell death are highly regulated events. Whether the cell will proceed through the cycle or not, depends upon whether the conditions required at the checkpoints during the cycle are fulfilled. In higher eucaryotic cells, such as mammalian cells, signals that arrest the cycle usually act at a G1 checkpoint. Cells that pass this restriction point are committed to complete the cycle. Regulation of the GI phase of the cell cycle is extremely complex and involves many different families of proteins such as retinoblastoma family cyclin dependent kinases, cyclins, and cyclic kinase inhibitors.展开更多
Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cycli...Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cyclin D cdk4,cyclin D cdk6 complex and have been implicated in a wide variety of cancer types,including the germline of patients with familial melanoma.In order to investigate and compare the status of p16,p15 gene in primary tumors and cell lines,we examined 357 primary tumors and 29 cell lines derived from diverse tumor types.In addition to analysis of these primary tumors and cell lines,blood specimens from 91 patients either with sporadic multiple cancers or from cancer prone families were also analyzed.The data showed the following:1)Homozygous deletions of p16,p15 were comparatively rare and far less common than previously reported,although hemizygous deletions were observed in a significant fraction of many tumor types;2)the incidence of p16,p15 deletions(either homozygous deletions or heterozygous deletions)varied significantly among different tumor types;3)most deletions involved in both p16 and p15 genes;4)sequence variations in the coding sequence of p16,p15 were comparatively rare among these tumor types,though mutations and polymorphisms were identified;5)some tumors which showed LOH at 9p,containing p16 and p15 gene,did not show deletions or point mutations in the p16,p15 gene.6)In a subset of retinoblastoma and osteosarcoma where no Rb gene mutations were present a significant fraction was found to contain p16,p15 gene deletions.展开更多
[Objective] This study aimed to research the effect of metallothionein on cell cycle, apoptosis rate and subsets distribution of lymphocytes in peripheral blood of dairy cows under heat stress, so as to perfect the re...[Objective] This study aimed to research the effect of metallothionein on cell cycle, apoptosis rate and subsets distribution of lymphocytes in peripheral blood of dairy cows under heat stress, so as to perfect the regulative mechanism re- searches of MT to anti-heat stress. [Method] Twenty lactating Chinese Holstein cows were randomly divided into four groups (A, B, C and D), and injected with 0, 4.0, 8.0 and 12.0 mg Zn-metallothionein, respectively by intravenous route. Blood sam- ples were collected at 1", 16~, 31~, 46~ and 61~ day, and the dynamic changes of cell cycle, apoptosis rate and subsets distribution of lymphocytes were determined. [Result] The apoptosis rate of cells in group B and C was lower than those in group A by 26.63% (P〉0.05) and 24.84% (P〉0.05) respectively. The number of cells in the Gc/G1 phage in trial groups was increased and the number of cells in the S and GJM phages tended to decrease, but there were no significant differences (P〉 0.05). The number of CD3~ T cell in three trial groups was greater than those in group A by 7.02% (P〉0.05), 5.45% (P〉0.05) and 3.85% (P〉0.05) respectively, while the number of CD4~ T cell in trial groups was higher than those in control group by 31.04% (P〈0.05), 35.68% (P〈0.05) and 39.34% (P〈0.05) respectively. The number of CD8' T cell and the levels of CD4*/CD8~ in trial groups were increased observ- ably, but significant difference (P〈0.05) was observed in the levels of CD4~/CD8~ between groups A and C only. It demonstrated that exogenous Zn-metallothionein can decrease apoptosis rate, improve cell cycle and regulate subsets distribution of lymphocytes in dairy cattle in a dose-dependent manner. [Conclusion] This study will provide scientific basis for safe utilization of MT in dairy industry.展开更多
Seasonal variation of biochemical components in clam(Saxidomus purpuratus Sowerby 1852) was investigated from March 2012 to February 2013 in relation to environmental condition of Sanggou Bay and the reproductive cycl...Seasonal variation of biochemical components in clam(Saxidomus purpuratus Sowerby 1852) was investigated from March 2012 to February 2013 in relation to environmental condition of Sanggou Bay and the reproductive cycle of clam.According to the histological analysis,the reproductive cycle of S.purpuratus includes two distinctive phases:a total spent and inactive stage from November to January,and a gametogenesis stage,including ripeness and spawning,during the rest of the year.Gametes were generated at a low temperature(2.1℃) in February.Spawning took place once a year from June to October.The massive spawning occurred in August when the highest water temperature and chlorophyll a level could be observed.The key biochemical components(glycogen,protein and lipid) in five tissues(gonad,foot,mantle,siphon and adductor muscle) were analyzed.The glycogen content was high before gametogenesis,and decreased significantly during the gonad development in the gonad,mantle and foot of both females and males,suggesting that glycogen was an important energy source for gonad development.The protein and lipid contents increased in the ovary during the gonad development,demonstrating that they are the major organic components of oocytes.The lipid and protein contents decreased in the testis,implying that they can provide energy and material for spermatogenesis.The results also showed that protein stored in the mantle and foot could support the reproduction after the glycogen was depleted.展开更多
Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproduc...Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproductive cycle of A. pectinata can be divided into two phases, inactive stage and gametogenesis, which were equally and significantly influenced by seawater temperature and food availability. Gametogenesis began in late autumn(October), and completed in June and July. Spawning took place in August, coinciding with the highest water temperature and the richest phytoplankton. The significantly high glycogen content in adductor muscles sustained throughout the late active and ripeness stages, but plummeted during spawning and inactive stages. The protein content in female gonads exhibited a synchronous increase along with oocyte diameter and lipid content, suggesting that the female gonads could accumulate protein and lipid for vitelline in A. pectinata. Furthermore, the RNA/DNA ratio was found to be a useful index to indicate the level of gonad maturation in both males and females. The findings of the present study provided a foundation for the fishery resource administration and the aquaculture development of this species.展开更多
Objective: To explore the possible mechanisms of growth regression of human androgen dependent prostate carcinoma cells caused by androgen withdrawal. Methods: After 24 h of treatment with 1 × 10-9 mol/L dihydrot...Objective: To explore the possible mechanisms of growth regression of human androgen dependent prostate carcinoma cells caused by androgen withdrawal. Methods: After 24 h of treatment with 1 × 10-9 mol/L dihydrotestosterone (DHT), the expression of phosphorylated ERK proteins and cell cycle regulation molecules including CDK2, CDK4, CDK6 and P27kip1 in human androgen dependent prostate carcinoma cell line LNCaP was measured by Western blot analysis 0 h, 8 h and 24 h of after androgen withdrawal. Human androgen independent prostate carcinoma cell line PC-3 was also examined as control. Results: Down-regulation of phosphorylated ERK, CDK2, CDK4 and CDK6 and up-regulation of P27kip1 were found initially in LNCaP cell line 8 h after androgen withdrawal. The levels of phosphorylated ERK and CDKs decreased continuously and reached the lowest after 24 h, while continuous elevation of P27kip1 was detected thereafter to 24 h. No expression change of phosphorylated ERK, CDKs and P27kip1 were detected in PC-3 cell line. Conclusion: The androgen withdrawal can cause ERKs activation decrease and cell cycle regulation molecules changes, which may be one of the mechanisms for inhibited growth of androgen dependent prostate carcinoma after androgen ablation by either operative or medicine methods.展开更多
From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive c...From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica.展开更多
In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a popul...In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects .4.japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments (light:dark (LD) cycles at 0:24, 3:21, 6:18, 9:15, 12:12, 15:9, 18:6, 21:3, and 24:0 under 500Ix) to 60 individuals (29.73±0.23 g) per treatment (with 3 replicates). The enviroramental conditions were set as: water temperature = 16.9±0.3℃, dissolved oxygen〉6.0 rag/L, ammonia〈0.3 mg/L, pH=7.8-8.2, and salinity=30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus (viz. the animals emerged and fed at night and sheltered during the day) were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate (DR) of the animals emerging at "daytime" increased with lengthening "light time" (except for the LD 3:21 cycle). We also found that there was no significant difference in mean DR per day under LD cycles of 6:18, 9:15, 15:9, and 12:12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0:24 and 3:21, and significantly higher than for those under LD cycles of 18:6, 21:3 and 24:0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus.展开更多
OBJECTIVE To investigate cyclin D1 expression in peripheral lung cancers and its relationship with CT signs and prognosis. METHODS Cyclin D1 expression in peripheral lung cancers and its relationship with the CT imagi...OBJECTIVE To investigate cyclin D1 expression in peripheral lung cancers and its relationship with CT signs and prognosis. METHODS Cyclin D1 expression in peripheral lung cancers and its relationship with the CT imaging and prognosis were analyzed retrospectively by means of SP immunohistochemistry and spiral CT scanning in 92 patients with peripheral lung cancer verified by pathology. RESULTS Cyclin D1 expression was related to deep lobulation,spiculate protuberance,short thin spinules sign and mediastina lymph node metastasis.Cyclin D1 expression was not related to tumor size,cavity,pleural indentation,histological type,differentiation,tumor TNM stage,age or sex.Cyclin D1 was a negative prognostic factor whose over-expression indicated a poor prognosis. CONCLUSION Cyclin D1 expression may play an important role in the occurrence,progress and CT scan results of lung cancers.Cyclin D1 was a negative factor whose over-expression implied a poor prognosis.Detection of the cyclin D1 and observation of the CT scan can be considered as indexes of clinical diagnosis and prognostic evaluation.展开更多
In this paper, the authors used the Princeton Ocean Model (POM) to simulate the seasonal evolu- tions of circulation and thermal structure in the Yellow Sea. The simulated circulation showed that the Yellow Sea Warm C...In this paper, the authors used the Princeton Ocean Model (POM) to simulate the seasonal evolu- tions of circulation and thermal structure in the Yellow Sea. The simulated circulation showed that the Yellow Sea Warm Current (YSWC) was a compensation current of monsoon-driven current, and that in winter, the YSWC became stronger with depth, and could flow across the Bohai Strait in the north. Sensitivity and control- ling tests led to the following conclusions. In winter, the direction of the Yellow Sea Coastal Current in the sur- face layer was controlled partly by tide instead of wind. In summer, a cyclonic horizontal gyre existed in the middle and eastern parts of the Yellow Sea below 10 m. The downwelling in upper layer and upwelling in lower layer were somehow similar to Hu et al. (1991) conceptual model. The calculated thermal structure showed an obvious northward extending YSWC tongue in winter, its position and coverage of the Yellow Sea Cold Water Mass in summer.展开更多
Plants become photosynthetic through de-etiolation, a developmental process regulated by red/far-red light-absorbing phytochromes and blue/ultraviolet A light-absorbing cryptochromes. Genetic screens have identified i...Plants become photosynthetic through de-etiolation, a developmental process regulated by red/far-red light-absorbing phytochromes and blue/ultraviolet A light-absorbing cryptochromes. Genetic screens have identified in the last decade many far-red light signaling mutants and several red and blue light signaling mutants, suggesting the existence of distinct red, far-red, or blue light signaling pathways downstream of phytochromes and cryptochromes. However, genetic screens have also identified mutants with defective de-etiolation responses under multiple wavelengths. Thus, the opti- mal de-etiolation responses of a plant depend on coordination among the different light signaling pathways. This review intends to discuss several recently identified signaling components that have a potential role to integrate red, far-red, and blue light signalings. This review also highlights the recent discoveries on proteolytic degradation in the desensitization of light signal transmission, and the tight connection of light signaling with photoperiodic flowering and circadian rhythm. Studies on the controlling mechanisms of de-etiolation, photoperiodic flowering, and circadian rhythm have been the fascinating topics in Arabidopsis research. The knowledge obtained from Arabidopsis can be readily applied to food crops and ornamental species, and can be contributed to our general understanding of signal perception and transduction in all organisms.展开更多
The male gametogenic cycle, spawning season, first sexual maturity, and the biological minimum size in male Ruditapes philippinarum were investigated by qualitative and quantitative reproductive analyses. In the study...The male gametogenic cycle, spawning season, first sexual maturity, and the biological minimum size in male Ruditapes philippinarum were investigated by qualitative and quantitative reproductive analyses. In the study of the male gametogenic cycle by qualitative histological analysis, the gametogenic cycle in male individuals can be classified into five successive stages: (1) early active stage, (2) late active stage, (3) ripe stage, (4) partially spawned stage, and (5) spent and inactive stage. Monthly changes in the gonad index in males measured by qualitative analysis showed a similar pattern to the male gametogenic cycle. In the study of the male gametogenic cycle by quantitative statistical analysis, monthly changes in the portions (%) of areas occupied by the testis areas to total tissue areas showed a rapid increase in March, and reached the maximum in May-June. And also monthly changes in the portions (%) of areas occupied by the spermatogenic stages to the testis area showed a maximum in May and gradually decreased from June to October. Therefore, this species showed a unimodal gametogenic cycle during the year, and the number of spawning seasons occurred once per year, from June to October, with a peak spawning between July and August. The percentage at the first sexual maturity of male clams ranging from 15.1-20.0 mm in shell length was 64.7%, and that of all individuals ranging from over 25.1 mm in shell length was 100%. The biological minimum size (shell lengths at 50% of sexual maturity (RMs0)) of male mature clams that was fitted to an exponential equation was 17.16 mm (considered to be 1 year old). Because harvesting clams less than 17.16 mm in shell length could potentially cause a drastic reduction in recruitment, a measure indicating a prohibitory fishing size should be enacted for adequate fisheries management.展开更多
文摘Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to undergo a step-wise oscillation. The hierarchic structures composed of both large and small domains were obtained. The mechanism of the periodic formation of hierarchic structures was also demonstrated.
文摘The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods.
文摘In any multi-cellular organism, the balance between cell division and cell death maintains a constant cell number. Both cell division cycle and cell death are highly regulated events. Whether the cell will proceed through the cycle or not, depends upon whether the conditions required at the checkpoints during the cycle are fulfilled. In higher eucaryotic cells, such as mammalian cells, signals that arrest the cycle usually act at a G1 checkpoint. Cells that pass this restriction point are committed to complete the cycle. Regulation of the GI phase of the cell cycle is extremely complex and involves many different families of proteins such as retinoblastoma family cyclin dependent kinases, cyclins, and cyclic kinase inhibitors.
文摘Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cyclin D cdk4,cyclin D cdk6 complex and have been implicated in a wide variety of cancer types,including the germline of patients with familial melanoma.In order to investigate and compare the status of p16,p15 gene in primary tumors and cell lines,we examined 357 primary tumors and 29 cell lines derived from diverse tumor types.In addition to analysis of these primary tumors and cell lines,blood specimens from 91 patients either with sporadic multiple cancers or from cancer prone families were also analyzed.The data showed the following:1)Homozygous deletions of p16,p15 were comparatively rare and far less common than previously reported,although hemizygous deletions were observed in a significant fraction of many tumor types;2)the incidence of p16,p15 deletions(either homozygous deletions or heterozygous deletions)varied significantly among different tumor types;3)most deletions involved in both p16 and p15 genes;4)sequence variations in the coding sequence of p16,p15 were comparatively rare among these tumor types,though mutations and polymorphisms were identified;5)some tumors which showed LOH at 9p,containing p16 and p15 gene,did not show deletions or point mutations in the p16,p15 gene.6)In a subset of retinoblastoma and osteosarcoma where no Rb gene mutations were present a significant fraction was found to contain p16,p15 gene deletions.
基金Supported by grants from the National Science Foundation of China(31072053,30671516)Natural Science Foundation of Hunan Province,China(11JJ2014)Specialized Research Fund for the Doctoral Program of Higher Education,Ministry of Education,China(20104320110001)
文摘[Objective] This study aimed to research the effect of metallothionein on cell cycle, apoptosis rate and subsets distribution of lymphocytes in peripheral blood of dairy cows under heat stress, so as to perfect the regulative mechanism re- searches of MT to anti-heat stress. [Method] Twenty lactating Chinese Holstein cows were randomly divided into four groups (A, B, C and D), and injected with 0, 4.0, 8.0 and 12.0 mg Zn-metallothionein, respectively by intravenous route. Blood sam- ples were collected at 1", 16~, 31~, 46~ and 61~ day, and the dynamic changes of cell cycle, apoptosis rate and subsets distribution of lymphocytes were determined. [Result] The apoptosis rate of cells in group B and C was lower than those in group A by 26.63% (P〉0.05) and 24.84% (P〉0.05) respectively. The number of cells in the Gc/G1 phage in trial groups was increased and the number of cells in the S and GJM phages tended to decrease, but there were no significant differences (P〉 0.05). The number of CD3~ T cell in three trial groups was greater than those in group A by 7.02% (P〉0.05), 5.45% (P〉0.05) and 3.85% (P〉0.05) respectively, while the number of CD4~ T cell in trial groups was higher than those in control group by 31.04% (P〈0.05), 35.68% (P〈0.05) and 39.34% (P〈0.05) respectively. The number of CD8' T cell and the levels of CD4*/CD8~ in trial groups were increased observ- ably, but significant difference (P〈0.05) was observed in the levels of CD4~/CD8~ between groups A and C only. It demonstrated that exogenous Zn-metallothionein can decrease apoptosis rate, improve cell cycle and regulate subsets distribution of lymphocytes in dairy cattle in a dose-dependent manner. [Conclusion] This study will provide scientific basis for safe utilization of MT in dairy industry.
基金supported by the grants from National Marine Public Welfare Research Program (201305005)Scientific and Technical Supporting Program (2011BA D13B01)National Natural Science Foundation of China (41276138)
文摘Seasonal variation of biochemical components in clam(Saxidomus purpuratus Sowerby 1852) was investigated from March 2012 to February 2013 in relation to environmental condition of Sanggou Bay and the reproductive cycle of clam.According to the histological analysis,the reproductive cycle of S.purpuratus includes two distinctive phases:a total spent and inactive stage from November to January,and a gametogenesis stage,including ripeness and spawning,during the rest of the year.Gametes were generated at a low temperature(2.1℃) in February.Spawning took place once a year from June to October.The massive spawning occurred in August when the highest water temperature and chlorophyll a level could be observed.The key biochemical components(glycogen,protein and lipid) in five tissues(gonad,foot,mantle,siphon and adductor muscle) were analyzed.The glycogen content was high before gametogenesis,and decreased significantly during the gonad development in the gonad,mantle and foot of both females and males,suggesting that glycogen was an important energy source for gonad development.The protein and lipid contents increased in the ovary during the gonad development,demonstrating that they are the major organic components of oocytes.The lipid and protein contents decreased in the testis,implying that they can provide energy and material for spermatogenesis.The results also showed that protein stored in the mantle and foot could support the reproduction after the glycogen was depleted.
基金supported by grants from the Scientific and Technical Supporting Program (No. 2011BAD13B01)the National Marine Public Welfare Research Program (No. 201305005)Doctoral Program of Ministry of Education of China (No. 20130132110009)
文摘Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproductive cycle of A. pectinata can be divided into two phases, inactive stage and gametogenesis, which were equally and significantly influenced by seawater temperature and food availability. Gametogenesis began in late autumn(October), and completed in June and July. Spawning took place in August, coinciding with the highest water temperature and the richest phytoplankton. The significantly high glycogen content in adductor muscles sustained throughout the late active and ripeness stages, but plummeted during spawning and inactive stages. The protein content in female gonads exhibited a synchronous increase along with oocyte diameter and lipid content, suggesting that the female gonads could accumulate protein and lipid for vitelline in A. pectinata. Furthermore, the RNA/DNA ratio was found to be a useful index to indicate the level of gonad maturation in both males and females. The findings of the present study provided a foundation for the fishery resource administration and the aquaculture development of this species.
文摘Objective: To explore the possible mechanisms of growth regression of human androgen dependent prostate carcinoma cells caused by androgen withdrawal. Methods: After 24 h of treatment with 1 × 10-9 mol/L dihydrotestosterone (DHT), the expression of phosphorylated ERK proteins and cell cycle regulation molecules including CDK2, CDK4, CDK6 and P27kip1 in human androgen dependent prostate carcinoma cell line LNCaP was measured by Western blot analysis 0 h, 8 h and 24 h of after androgen withdrawal. Human androgen independent prostate carcinoma cell line PC-3 was also examined as control. Results: Down-regulation of phosphorylated ERK, CDK2, CDK4 and CDK6 and up-regulation of P27kip1 were found initially in LNCaP cell line 8 h after androgen withdrawal. The levels of phosphorylated ERK and CDKs decreased continuously and reached the lowest after 24 h, while continuous elevation of P27kip1 was detected thereafter to 24 h. No expression change of phosphorylated ERK, CDKs and P27kip1 were detected in PC-3 cell line. Conclusion: The androgen withdrawal can cause ERKs activation decrease and cell cycle regulation molecules changes, which may be one of the mechanisms for inhibited growth of androgen dependent prostate carcinoma after androgen ablation by either operative or medicine methods.
基金the National Marine Public Welfare Research Program(201205023)the Scientific and Technical Supporting Program(2011BAD13B03)
文摘From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica.
基金Supported by the National Natural Science Foundation of China (Nos. 30871931, 30771661)the National Key Technology Research and Development Program of China (Nos. 2006BAD09A01)the National Special Research Fund for Non-Profit Sector (No. 200905020)
文摘In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects .4.japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments (light:dark (LD) cycles at 0:24, 3:21, 6:18, 9:15, 12:12, 15:9, 18:6, 21:3, and 24:0 under 500Ix) to 60 individuals (29.73±0.23 g) per treatment (with 3 replicates). The enviroramental conditions were set as: water temperature = 16.9±0.3℃, dissolved oxygen〉6.0 rag/L, ammonia〈0.3 mg/L, pH=7.8-8.2, and salinity=30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus (viz. the animals emerged and fed at night and sheltered during the day) were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate (DR) of the animals emerging at "daytime" increased with lengthening "light time" (except for the LD 3:21 cycle). We also found that there was no significant difference in mean DR per day under LD cycles of 6:18, 9:15, 15:9, and 12:12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0:24 and 3:21, and significantly higher than for those under LD cycles of 18:6, 21:3 and 24:0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus.
基金grants from Natural Science Foundation of Guangdong,China (No.06301077)Administration of Tradi-tional Chinese Medicine of Guangdong,China (No.2060134)+1 种基金the Health Department Foun-dation of Guangdong,China (No.A2007421)the Shantou Technology Bureau Science Foundation of China (No.Shantou Govern-ment Technology[2006]85)
文摘OBJECTIVE To investigate cyclin D1 expression in peripheral lung cancers and its relationship with CT signs and prognosis. METHODS Cyclin D1 expression in peripheral lung cancers and its relationship with the CT imaging and prognosis were analyzed retrospectively by means of SP immunohistochemistry and spiral CT scanning in 92 patients with peripheral lung cancer verified by pathology. RESULTS Cyclin D1 expression was related to deep lobulation,spiculate protuberance,short thin spinules sign and mediastina lymph node metastasis.Cyclin D1 expression was not related to tumor size,cavity,pleural indentation,histological type,differentiation,tumor TNM stage,age or sex.Cyclin D1 was a negative prognostic factor whose over-expression indicated a poor prognosis. CONCLUSION Cyclin D1 expression may play an important role in the occurrence,progress and CT scan results of lung cancers.Cyclin D1 was a negative factor whose over-expression implied a poor prognosis.Detection of the cyclin D1 and observation of the CT scan can be considered as indexes of clinical diagnosis and prognostic evaluation.
基金Contribution No. 4616 from Institute of Oceanology, CAS. Project No.40406025 supported by NSFC.
文摘In this paper, the authors used the Princeton Ocean Model (POM) to simulate the seasonal evolu- tions of circulation and thermal structure in the Yellow Sea. The simulated circulation showed that the Yellow Sea Warm Current (YSWC) was a compensation current of monsoon-driven current, and that in winter, the YSWC became stronger with depth, and could flow across the Bohai Strait in the north. Sensitivity and control- ling tests led to the following conclusions. In winter, the direction of the Yellow Sea Coastal Current in the sur- face layer was controlled partly by tide instead of wind. In summer, a cyclonic horizontal gyre existed in the middle and eastern parts of the Yellow Sea below 10 m. The downwelling in upper layer and upwelling in lower layer were somehow similar to Hu et al. (1991) conceptual model. The calculated thermal structure showed an obvious northward extending YSWC tongue in winter, its position and coverage of the Yellow Sea Cold Water Mass in summer.
文摘Plants become photosynthetic through de-etiolation, a developmental process regulated by red/far-red light-absorbing phytochromes and blue/ultraviolet A light-absorbing cryptochromes. Genetic screens have identified in the last decade many far-red light signaling mutants and several red and blue light signaling mutants, suggesting the existence of distinct red, far-red, or blue light signaling pathways downstream of phytochromes and cryptochromes. However, genetic screens have also identified mutants with defective de-etiolation responses under multiple wavelengths. Thus, the opti- mal de-etiolation responses of a plant depend on coordination among the different light signaling pathways. This review intends to discuss several recently identified signaling components that have a potential role to integrate red, far-red, and blue light signalings. This review also highlights the recent discoveries on proteolytic degradation in the desensitization of light signal transmission, and the tight connection of light signaling with photoperiodic flowering and circadian rhythm. Studies on the controlling mechanisms of de-etiolation, photoperiodic flowering, and circadian rhythm have been the fascinating topics in Arabidopsis research. The knowledge obtained from Arabidopsis can be readily applied to food crops and ornamental species, and can be contributed to our general understanding of signal perception and transduction in all organisms.
文摘The male gametogenic cycle, spawning season, first sexual maturity, and the biological minimum size in male Ruditapes philippinarum were investigated by qualitative and quantitative reproductive analyses. In the study of the male gametogenic cycle by qualitative histological analysis, the gametogenic cycle in male individuals can be classified into five successive stages: (1) early active stage, (2) late active stage, (3) ripe stage, (4) partially spawned stage, and (5) spent and inactive stage. Monthly changes in the gonad index in males measured by qualitative analysis showed a similar pattern to the male gametogenic cycle. In the study of the male gametogenic cycle by quantitative statistical analysis, monthly changes in the portions (%) of areas occupied by the testis areas to total tissue areas showed a rapid increase in March, and reached the maximum in May-June. And also monthly changes in the portions (%) of areas occupied by the spermatogenic stages to the testis area showed a maximum in May and gradually decreased from June to October. Therefore, this species showed a unimodal gametogenic cycle during the year, and the number of spawning seasons occurred once per year, from June to October, with a peak spawning between July and August. The percentage at the first sexual maturity of male clams ranging from 15.1-20.0 mm in shell length was 64.7%, and that of all individuals ranging from over 25.1 mm in shell length was 100%. The biological minimum size (shell lengths at 50% of sexual maturity (RMs0)) of male mature clams that was fitted to an exponential equation was 17.16 mm (considered to be 1 year old). Because harvesting clams less than 17.16 mm in shell length could potentially cause a drastic reduction in recruitment, a measure indicating a prohibitory fishing size should be enacted for adequate fisheries management.