To characterize the preclinical pharmacokinetics, tissue distribution and excretion profiles of exendin-4 in healthy Wistar rats were studied. Exendin-4 was radioiodinated by the IODOGEN (1,3,4,6-tetrachloro-3 alpha,...To characterize the preclinical pharmacokinetics, tissue distribution and excretion profiles of exendin-4 in healthy Wistar rats were studied. Exendin-4 was radioiodinated by the IODOGEN (1,3,4,6-tetrachloro-3 alpha, 6 alphadiphenylglucoluril) method. Pharrnacokinetic properties of ^125I-exendin-4 were examined after a single s.c. and i.v. injection, respectively. Tissue distri- bution and urinary, fecal, and biliary excretion patterns of ^125I-exendin-4 were also investigated following a single s.c. injection. Exendin-4 was rapidly distributed and cleared with t1/2 of (0.48 ± 0.03) h after a single i.v. injection. Following a single s.c. administration, exendin-4 exhibited rapid and considerable absorption with Tmax of (0.25± 0.02) h and declined with the elimination t1/2 of(1.28± 0.14) h. The absolute bioavailability was (65.5 ± 10.2) %. The radioactivity was widely distributed and rapidly diminished in most tissues. The kidney contained the highest radioactivity and the distribution of ^125I-exendin-4 to the brain was minimal. The major elimination route was urinary excretion. The pharmacokinetic properties of exendin-4 obtained from the present study closely matched those reported in previous studies in rats. Pharmacokinetics profiles of exendin-4 in rats are warranted for the design of future clinical trials.展开更多
Sn was used to replace Al in Co38Ni34Al28 alloy. The microstructure and microhardness of Co38Ni34Al28-xSnx (x=0, 1, 2, 3) magnetic shape memory alloys were investigated at different heat treatment temperatures (137...Sn was used to replace Al in Co38Ni34Al28 alloy. The microstructure and microhardness of Co38Ni34Al28-xSnx (x=0, 1, 2, 3) magnetic shape memory alloys were investigated at different heat treatment temperatures (1373 K, 1473 K, and 1573 K) for 2 h. The results show that more Sn substitution reduces the content of γ-phase and a partial phase of martensite can be obtained in Co38Ni34Al28-xSnx (x=1, 2, 3) alloys after treatment at 1573 K for 2 h. The maximum martensite phase appears when 2% Al is substituted by Sn. The reverse martensitic transformation temperature of Co38Ni34Al28-xSnx alloys increases at x=1 and 2, then decreases as x=3. As the content of Sn and the temperature increase, the microhardness will increase.展开更多
AIM: To study the response to infliximab in pediatric inflammatory bowel disease (IBD), as reflected in fecal calprotectin levels. METHODS: Thirty-six pediatric patients with IBD [23 Crohn's disease (CD), 13 ulcer...AIM: To study the response to infliximab in pediatric inflammatory bowel disease (IBD), as reflected in fecal calprotectin levels. METHODS: Thirty-six pediatric patients with IBD [23 Crohn's disease (CD), 13 ulcerative colitis (UC); median age 14 years] were treated with infliximab. Fecal calprotectin was measured at baseline, and 2 and 6 wk after therapy, and compared to blood inflammatory markers. Maintenance medication was unaltered until the third infusion but glucocorticoids were tapered off if the patient was doing well. RESULTS: At introduction of infliximab, median fecal calprotectin level was 1150 μg/g (range 54-6032 μg/g). By week 2, the fecal calprotectin level had declined to amedian 261 μg/g (P < 0.001). In 37% of the patients, fecal calprotectin was normal (< 100 μg/g) at 2 wk. By week 6, there was no additional improvement in the fecal calprotectin level (median 345 μg/g). In 22% of the patients, fecal calprotectin levels increased by week 6 to pretreatment levels or above, suggesting no response (or a loss of early response). Thus, in CD, the proportion of non-responsive patients by week 6 seemed lower, because only 9% showed no improvement in their fecal calprotectin level when compared to the respective figure of 46% of the UC patients (P < 0.05). CONCLUSION: When treated with infliximab, fecal calprotectin levels reflecting intestinal inflammation normalized rapidly in one third of pediatric patients suggesting complete mucosal healing.展开更多
Toni Morrison's fiction may arguably be characterized as postmodern discourse on memory, history and culture. In her novels, the Nobel laureate frequently returns to the past to search for answers to the questions sh...Toni Morrison's fiction may arguably be characterized as postmodern discourse on memory, history and culture. In her novels, the Nobel laureate frequently returns to the past to search for answers to the questions she poses about African American realities in the contemporary United States. In doing so, Morrison often creates alternative histories or, more specifically, a usable past----one that allows her to engage in a literary (re-)construction of the Black historical and cultural material which traditional histories have chosen to ignore or disremember. Therefore, as a present-day writer of African American descent, Morrison attempts to reassemble all the fragmentary historical and cultural accounts available to her as a novelist and narrate them in the form of a convincing story. With regard to the above considerations, this article seeks to discuss some of the mechanisms employed by Morrison for weaving her postmodern, memory-filled narrative on the example of her eighth novel, Love (2003). In particular, the analysis focuses on the book's central figure, Bill Cosey, and his Southern ocean-side resort--both seen against the backdrop of the pre- and post-World War II racist America, followed by the 1960s decade of the Civil Rights Movement. Finally, it is also demonstrated how the author's use of split narrative as well as the "I" narrator-cum-character technique contribute to recounting in retrospect Love's main, historicized story---one viewed and judged from a present-time perspective.展开更多
Recently, proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. Although many proxy ring signature schemes have been pro-posed, there a...Recently, proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. Although many proxy ring signature schemes have been pro-posed, there are only two identity-based proxy ring signature schemes have been proposed until now, i. e., Cheng's scheme and Lang's scheme. It's unlucky that the two identity-based proxy ring signature schemes are unfeasible. This paper points out the reasons why the two identity-based proxy ring signature schemes are unfeasible. In order to design feasible and efficient identity-based proxy ring signature schemes from bilinear pairings, we have to search for other methods.展开更多
Objective: To investigate the effects of lithium on cognitive function and metabolism of Amyloid-beta Protein Precursor (APP) and tau phosphorylation in rats chronically exposed to aluminum. Methods: Twenty-four chron...Objective: To investigate the effects of lithium on cognitive function and metabolism of Amyloid-beta Protein Precursor (APP) and tau phosphorylation in rats chronically exposed to aluminum. Methods: Twenty-four chronically aluminum-exposed rats were randomly divided into 2 groups: a lithium-treatment group and a non-treatment group (n=12 per group). Lithium chloride was administered to the lithium-treatment group via gastric gavage daily for 6 weeks (200 mg/kg·d LiCl), while the non-treatment group was administered the same volume of sodium chloride by the same means. An additional control group (n=12) received no intervention. Memory function was evaluated by the Morris water maze test. Aβ was measured by immunohistochemical staining, while total APP, phosphorylated-tau protein, CDK5 and PP2A were determined by Western Blotting. Results: (1) Compared to the non-treatment group, the lithium-treatment group had a significantly shorter mean escape latency and a lower proportion of random navigation pattern in the spatial probe test (P<0.05). After the platform was taken away, the rats in the lithium-treatment group crossed the platform quadrant significantly more and stayed longer in the platform quadrant than those in the non-treatment group (P<0.05). (2) The number of Aβ positive neurons in the hippocampus and cortex was significantly less in the lithium-treatment group than in the non-treatment group (P<0.05), but the content of APP was not different between groups (P=0.730). (3) Phosphorylation of tau protein decreased significantly in the lithium-treatment group than that in the non-treatment group (P<0.05). The content of CDK5 in the lithium-treatment group was significantly less than that in the non-treatment group in the cortex and hippocampus, while there was no difference in the content of PP2A between the 2 groups. The expression of CDK5 was significantly correlated with phosphorylated tau (r=0.871, P=0.024) in the lithium-treatment group. Conclusion: Lithium may improve memory function in rats chronically exposed to aluminum by decreasing both the production of Aβ and tau phosphorylation, with the latter results from inhibiting expression of CDK5.展开更多
The calibration of paleoclimate proxies is one of the key problems in the study of paleoclimate at present. Historical documentary records of climate are suitable for calibration on dating and the climatic implication...The calibration of paleoclimate proxies is one of the key problems in the study of paleoclimate at present. Historical documentary records of climate are suitable for calibration on dating and the climatic implication of the proxy data in a climatological sense. A test calibration on correcting the Delingha tree ring precipitation series using Chinese historical documentary records shows that among the 44 extreme dry cases in 1401 1950 AD, 42 cases (or 95.5%) are believable. Thus the long series of Delingha rings-denoted precipitation is highly reliable. Another test to validate the monsoon intensity proxy data based on the Zhanjiang Huguangyan sediments using historical records indicates that the years of Lake Maar Ti content series-designated winter monsoon intensities are entirely opposite to historical documents- depicted years of harsh winters in 800-900 AD. As a result, serious doubt is raised about the climatic implication of this paleo-monsoon proxy series.展开更多
AIM: To investigate the relationship of changes in expression of marker genes in functional categories or molecular networks comprising one functional category or multiple categories in progression of hepatic fibrosis...AIM: To investigate the relationship of changes in expression of marker genes in functional categories or molecular networks comprising one functional category or multiple categories in progression of hepatic fibrosis in hepatitis C (HCV) patients. METHODS: Marker genes were initially identified using DNA microarray data from a rat liver fibrosis model. The expression level of each fibrosis associated marker gene was analyzed using reverse transcription-polymerase chain reaction (RT-PCR) in clinical biopsy specimens from HCV-positive patients (n = 61). Analysis of changes in expression patterns and interactions of marker genes in functional categories was used to assess the biological mechanism of fibrosis. RESULTS: The profile data showed several biological changes associated with progression of hepatic fibrosis. Clustered genes in functional categories showed sequential changes in expression. Several sets of clustered genes, including those related to the extracellular matrix (ECM), inflammation, lipid metabolism, steroid metabolism, and some transcription factors important for hepatic biology showed expression changes in the immediate early phase (F1/F2) of fibrosis. Genes associated with aromatic amino acid (AA) metabolism, sulfur-containing AA metabolism and insulin/ Wnt signaling showed expression changes in the middle phase (F2/F3), and some genes related to glucose metabolism showed altered expression in the late phase of fibrosis (F3/F4). Therefore, molecular networks showing serial changes in gene expression are present in liver fibrosis progression in hepatitis C patients. CONCLUSION: Analysis of gene expression profiles from a perspective of functional categories or molecular networks provides an understanding of disease and suggests new diagnostic methods. Selected marker genes have potential utility for biological identification of advanced fibrosis.展开更多
Yan Shigu, a famous linguist, scribe and historian of the Tang Dynasty, is most famous as a linguist. Since he has no monograph on linguistics, his main thoughts lie in books like Han Shu Zhu. His achievements in ling...Yan Shigu, a famous linguist, scribe and historian of the Tang Dynasty, is most famous as a linguist. Since he has no monograph on linguistics, his main thoughts lie in books like Han Shu Zhu. His achievements in linguistics make a big difference in the history of Chinese linguistics.展开更多
This paper describes optimization process of nozzle cup based on a device for contactless code marking to rough and contaminated surfaces--semiautomatic code marker. During tests using the CFD (computational fluid dy...This paper describes optimization process of nozzle cup based on a device for contactless code marking to rough and contaminated surfaces--semiautomatic code marker. During tests using the CFD (computational fluid dynamics) software different geometry of nozzle cups were compared by such parameters as pressure, velocity and direction of flow. Goal of digital experiments was to find sprayer nozzle geometry that can keep stream of paint in diameter of 10 mm on 10-20 mm distance. Main problem is to avoid low-pressure regions around the stream. The optimal geometry of nozzle cup is designed to get adjusted code dimensions on given distance展开更多
Inter individual differences in the metabolism of antimalarials could be due to polymorphism of NAT2 gene. The authors determined the genotypic frequencies of single nucleotide polymorphism (SNP) of NAT2 gene and it...Inter individual differences in the metabolism of antimalarials could be due to polymorphism of NAT2 gene. The authors determined the genotypic frequencies of single nucleotide polymorphism (SNP) of NAT2 gene and it's implication in antimalarial treatment during a vitamin A and zinc supplementation intervention in children aged 6 to 24 months. Children were deparasitized with artesunate-amodiaquine (ASAQ)-toddler 50/135 mg. Pharmacovigilance was done for 40 days, adverse events recorded and blood was spotted on filter paper for DNA extraction by chelex method. PCR-RFLP was performed with restriction enzymes KpnI, TaqI, and BamHl for detection of SNPs of NAT2. Allelic frequencies and phenotypes were compared between participants with or without adverse drug events. The prevalence of fast, slow and intermediate acetylators was 55%, 30% and 11% respectively. There was a significant association (P = 0.035) between NAT2 slow acetylators (and susceptibility to develop skin rash. No significant difference was observed between fast and slow acetylators and susceptibility to develop fever, anorexia, cough and common cold. Slow acetylators were more susceptible, (P = 0.011) to develop any adverse event The NAT2 slow acetylator phenotype was the most predominant and individuals with this phenotype were more significantly susceptible to develop adverse events to ASAQ.展开更多
The effect of Batroxobin expression of neural cell adhesion molecule (NCAM) in left temporal ischemic rats with spatial memory disorder was investigated by means of Morri's water maze and immunohistochemical metho...The effect of Batroxobin expression of neural cell adhesion molecule (NCAM) in left temporal ischemic rats with spatial memory disorder was investigated by means of Morri's water maze and immunohistochemical methods. The results showed that the mean reaction time and distance of temporal ischemic rats for searching a goal were significantly longer than those of sham-operated rats and at the same time NCAM expression of left temporal ischemic region was significantly increased. However, the mean reaction time and distance of Batroxobin-treated rats were shorter and they used normal strategies more often and earlier than those of ischemic rats. The number of NCAM immune reactive cells of Batroxobin-treated rats was more than that of ischemic group. In conclusion, Batroxobin can improve spatial memory disorder of temporal ischemic rats and the regulation of the expression of NCAM is probably related to the neuroprotective mechanism.展开更多
A rapid and sensitive fluorescence labeling method was developed and validated for the microanalysis of a sulfated polysaccharide drug,namely propylene glycol alginate sodium sulfate(PSS), in rat plasma. Fluorescein i...A rapid and sensitive fluorescence labeling method was developed and validated for the microanalysis of a sulfated polysaccharide drug,namely propylene glycol alginate sodium sulfate(PSS), in rat plasma. Fluorescein isothiocyanate(FITC) was selected to label PSS, and 1, 6-diaminohexane was used to link PSS and FITC in order to prepare FITC-labeled PSS(F-PSS) through a reductive amination reaction. F-PSS was identified by UV-Vis, FT-IR and 1H-NMR spectrum. The cell stability and cytotoxicity of F-PSS were tested in Madin-Darby canine kidney(MDCK) cells. The results indicated that the labeling efficiency of F-PSS was 0.522% ± 0.0248% and the absolute bioavailability was 8.39%. F-PSS was stable in MDCK cells without obvious cytotoxicity. The method was sensitive and reliable; it showed a good linearity, precision, recovery and stability. The FITC labeling method can be applied to investigating the absorption and metabolism of PSS and other polysaccharides in biological samples.展开更多
In order to monitor the deformations of modern constructions a local 3D network was usually being established at the surrounding area. The centering error, of both the instrument and targets, causes significant uncert...In order to monitor the deformations of modern constructions a local 3D network was usually being established at the surrounding area. The centering error, of both the instrument and targets, causes significant uncertainties in the determination of the x, y, z coordinates of the network's points. In order to assure precise centering for both the instrument and targets, not only for the accessible but also for the inaccessible network's points, a prototype way of marking is being implied. A special semi-permanent portable metallic stand (Photo 1) was manufactured for marking the accessible points. The stand provides forced instrument centering of the order of_+0, lmm. It is light enough to carry, it accelerates and facilitates the centering and leveling of the instrument as well as it eliminates the time needed for the measurements. The applied laboratory checks in order to certify the suitability of its use and the provided accuracy are being described. For the inaccessible points special targets were used. The targets were put in permanent attachments (Photos 7-8), which were also manufactured. Useful conclusions were drawn when these special accessories were used in to a 3D network, which was established for the monitoring of a new football stadium. Two measurement phases were carried out. The first one is with the stadium empty and the second one is when it was crowded (about 32000 people) during a significant football match.展开更多
Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical ...Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(< 10 k Da at 24 h). In summary, HP-chitosan has excellent bioavailability and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.展开更多
In the first two-thirds of The Golden Notebook (1962), the theme of the crack-up or breakdown is elaborated in the novels representation of national and global politics. Soviet-inspired communism, European coloniali...In the first two-thirds of The Golden Notebook (1962), the theme of the crack-up or breakdown is elaborated in the novels representation of national and global politics. Soviet-inspired communism, European colonialism and emperialism, Britain society, and national liberation struggles in the Third World are disintegrating, collapsing, crumbling, and fragmenting, under the pressures both internal and external. The last third of the novel relocates the crack-up in the person, [...], of Anna herself. In this paper, the author attempts to show that L The Golden Notebook on the central theme of "Breakdown, Fragmentation, and Disintegration", essing has written which shows that sometimes when people "crack-up", it is a way of self-healing. This theme finds an expression in the novel and this paper shows how Anna Wulf, the protagonist, tries to deal with her inner self-divisions, what part is played by each of Anna's four notebooks in her struggle to integrate her fragmented inner world and personality, what enables the notebooks to come together in the golden notebook at the end of the novel, and finally, how about her relationships to others, especially to Saul Green, contribute to her "crack-up" and "self-healing"展开更多
基金National High Technology 863 Project (Grant No. 2003AA2Z347B)
文摘To characterize the preclinical pharmacokinetics, tissue distribution and excretion profiles of exendin-4 in healthy Wistar rats were studied. Exendin-4 was radioiodinated by the IODOGEN (1,3,4,6-tetrachloro-3 alpha, 6 alphadiphenylglucoluril) method. Pharrnacokinetic properties of ^125I-exendin-4 were examined after a single s.c. and i.v. injection, respectively. Tissue distri- bution and urinary, fecal, and biliary excretion patterns of ^125I-exendin-4 were also investigated following a single s.c. injection. Exendin-4 was rapidly distributed and cleared with t1/2 of (0.48 ± 0.03) h after a single i.v. injection. Following a single s.c. administration, exendin-4 exhibited rapid and considerable absorption with Tmax of (0.25± 0.02) h and declined with the elimination t1/2 of(1.28± 0.14) h. The absolute bioavailability was (65.5 ± 10.2) %. The radioactivity was widely distributed and rapidly diminished in most tissues. The kidney contained the highest radioactivity and the distribution of ^125I-exendin-4 to the brain was minimal. The major elimination route was urinary excretion. The pharmacokinetic properties of exendin-4 obtained from the present study closely matched those reported in previous studies in rats. Pharmacokinetics profiles of exendin-4 in rats are warranted for the design of future clinical trials.
基金Projects (50771037, 50371020) supported by the National Natural Science Foundation of ChinaProject (2011B090400485) supported by the Combination Project for Guangdong Province and the Ministry of Education, China
文摘Sn was used to replace Al in Co38Ni34Al28 alloy. The microstructure and microhardness of Co38Ni34Al28-xSnx (x=0, 1, 2, 3) magnetic shape memory alloys were investigated at different heat treatment temperatures (1373 K, 1473 K, and 1573 K) for 2 h. The results show that more Sn substitution reduces the content of γ-phase and a partial phase of martensite can be obtained in Co38Ni34Al28-xSnx (x=1, 2, 3) alloys after treatment at 1573 K for 2 h. The maximum martensite phase appears when 2% Al is substituted by Sn. The reverse martensitic transformation temperature of Co38Ni34Al28-xSnx alloys increases at x=1 and 2, then decreases as x=3. As the content of Sn and the temperature increase, the microhardness will increase.
基金Supported by The Finnish Pediatric Research Foundationthe Pivikki and Sakari Sohlberg Foundation+1 种基金the Mary and Georg C Ehrnrooth Foundationthe Helsinki University Central Hospital Research Fund
文摘AIM: To study the response to infliximab in pediatric inflammatory bowel disease (IBD), as reflected in fecal calprotectin levels. METHODS: Thirty-six pediatric patients with IBD [23 Crohn's disease (CD), 13 ulcerative colitis (UC); median age 14 years] were treated with infliximab. Fecal calprotectin was measured at baseline, and 2 and 6 wk after therapy, and compared to blood inflammatory markers. Maintenance medication was unaltered until the third infusion but glucocorticoids were tapered off if the patient was doing well. RESULTS: At introduction of infliximab, median fecal calprotectin level was 1150 μg/g (range 54-6032 μg/g). By week 2, the fecal calprotectin level had declined to amedian 261 μg/g (P < 0.001). In 37% of the patients, fecal calprotectin was normal (< 100 μg/g) at 2 wk. By week 6, there was no additional improvement in the fecal calprotectin level (median 345 μg/g). In 22% of the patients, fecal calprotectin levels increased by week 6 to pretreatment levels or above, suggesting no response (or a loss of early response). Thus, in CD, the proportion of non-responsive patients by week 6 seemed lower, because only 9% showed no improvement in their fecal calprotectin level when compared to the respective figure of 46% of the UC patients (P < 0.05). CONCLUSION: When treated with infliximab, fecal calprotectin levels reflecting intestinal inflammation normalized rapidly in one third of pediatric patients suggesting complete mucosal healing.
文摘Toni Morrison's fiction may arguably be characterized as postmodern discourse on memory, history and culture. In her novels, the Nobel laureate frequently returns to the past to search for answers to the questions she poses about African American realities in the contemporary United States. In doing so, Morrison often creates alternative histories or, more specifically, a usable past----one that allows her to engage in a literary (re-)construction of the Black historical and cultural material which traditional histories have chosen to ignore or disremember. Therefore, as a present-day writer of African American descent, Morrison attempts to reassemble all the fragmentary historical and cultural accounts available to her as a novelist and narrate them in the form of a convincing story. With regard to the above considerations, this article seeks to discuss some of the mechanisms employed by Morrison for weaving her postmodern, memory-filled narrative on the example of her eighth novel, Love (2003). In particular, the analysis focuses on the book's central figure, Bill Cosey, and his Southern ocean-side resort--both seen against the backdrop of the pre- and post-World War II racist America, followed by the 1960s decade of the Civil Rights Movement. Finally, it is also demonstrated how the author's use of split narrative as well as the "I" narrator-cum-character technique contribute to recounting in retrospect Love's main, historicized story---one viewed and judged from a present-time perspective.
基金Supported by the National Natural Science Foundation of China (No.60432040).
文摘Recently, proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. Although many proxy ring signature schemes have been pro-posed, there are only two identity-based proxy ring signature schemes have been proposed until now, i. e., Cheng's scheme and Lang's scheme. It's unlucky that the two identity-based proxy ring signature schemes are unfeasible. This paper points out the reasons why the two identity-based proxy ring signature schemes are unfeasible. In order to design feasible and efficient identity-based proxy ring signature schemes from bilinear pairings, we have to search for other methods.
文摘Objective: To investigate the effects of lithium on cognitive function and metabolism of Amyloid-beta Protein Precursor (APP) and tau phosphorylation in rats chronically exposed to aluminum. Methods: Twenty-four chronically aluminum-exposed rats were randomly divided into 2 groups: a lithium-treatment group and a non-treatment group (n=12 per group). Lithium chloride was administered to the lithium-treatment group via gastric gavage daily for 6 weeks (200 mg/kg·d LiCl), while the non-treatment group was administered the same volume of sodium chloride by the same means. An additional control group (n=12) received no intervention. Memory function was evaluated by the Morris water maze test. Aβ was measured by immunohistochemical staining, while total APP, phosphorylated-tau protein, CDK5 and PP2A were determined by Western Blotting. Results: (1) Compared to the non-treatment group, the lithium-treatment group had a significantly shorter mean escape latency and a lower proportion of random navigation pattern in the spatial probe test (P<0.05). After the platform was taken away, the rats in the lithium-treatment group crossed the platform quadrant significantly more and stayed longer in the platform quadrant than those in the non-treatment group (P<0.05). (2) The number of Aβ positive neurons in the hippocampus and cortex was significantly less in the lithium-treatment group than in the non-treatment group (P<0.05), but the content of APP was not different between groups (P=0.730). (3) Phosphorylation of tau protein decreased significantly in the lithium-treatment group than that in the non-treatment group (P<0.05). The content of CDK5 in the lithium-treatment group was significantly less than that in the non-treatment group in the cortex and hippocampus, while there was no difference in the content of PP2A between the 2 groups. The expression of CDK5 was significantly correlated with phosphorylated tau (r=0.871, P=0.024) in the lithium-treatment group. Conclusion: Lithium may improve memory function in rats chronically exposed to aluminum by decreasing both the production of Aβ and tau phosphorylation, with the latter results from inhibiting expression of CDK5.
基金supported in part by National Science Foundation of China(41075055)
文摘The calibration of paleoclimate proxies is one of the key problems in the study of paleoclimate at present. Historical documentary records of climate are suitable for calibration on dating and the climatic implication of the proxy data in a climatological sense. A test calibration on correcting the Delingha tree ring precipitation series using Chinese historical documentary records shows that among the 44 extreme dry cases in 1401 1950 AD, 42 cases (or 95.5%) are believable. Thus the long series of Delingha rings-denoted precipitation is highly reliable. Another test to validate the monsoon intensity proxy data based on the Zhanjiang Huguangyan sediments using historical records indicates that the years of Lake Maar Ti content series-designated winter monsoon intensities are entirely opposite to historical documents- depicted years of harsh winters in 800-900 AD. As a result, serious doubt is raised about the climatic implication of this paleo-monsoon proxy series.
文摘AIM: To investigate the relationship of changes in expression of marker genes in functional categories or molecular networks comprising one functional category or multiple categories in progression of hepatic fibrosis in hepatitis C (HCV) patients. METHODS: Marker genes were initially identified using DNA microarray data from a rat liver fibrosis model. The expression level of each fibrosis associated marker gene was analyzed using reverse transcription-polymerase chain reaction (RT-PCR) in clinical biopsy specimens from HCV-positive patients (n = 61). Analysis of changes in expression patterns and interactions of marker genes in functional categories was used to assess the biological mechanism of fibrosis. RESULTS: The profile data showed several biological changes associated with progression of hepatic fibrosis. Clustered genes in functional categories showed sequential changes in expression. Several sets of clustered genes, including those related to the extracellular matrix (ECM), inflammation, lipid metabolism, steroid metabolism, and some transcription factors important for hepatic biology showed expression changes in the immediate early phase (F1/F2) of fibrosis. Genes associated with aromatic amino acid (AA) metabolism, sulfur-containing AA metabolism and insulin/ Wnt signaling showed expression changes in the middle phase (F2/F3), and some genes related to glucose metabolism showed altered expression in the late phase of fibrosis (F3/F4). Therefore, molecular networks showing serial changes in gene expression are present in liver fibrosis progression in hepatitis C patients. CONCLUSION: Analysis of gene expression profiles from a perspective of functional categories or molecular networks provides an understanding of disease and suggests new diagnostic methods. Selected marker genes have potential utility for biological identification of advanced fibrosis.
文摘Yan Shigu, a famous linguist, scribe and historian of the Tang Dynasty, is most famous as a linguist. Since he has no monograph on linguistics, his main thoughts lie in books like Han Shu Zhu. His achievements in linguistics make a big difference in the history of Chinese linguistics.
文摘This paper describes optimization process of nozzle cup based on a device for contactless code marking to rough and contaminated surfaces--semiautomatic code marker. During tests using the CFD (computational fluid dynamics) software different geometry of nozzle cups were compared by such parameters as pressure, velocity and direction of flow. Goal of digital experiments was to find sprayer nozzle geometry that can keep stream of paint in diameter of 10 mm on 10-20 mm distance. Main problem is to avoid low-pressure regions around the stream. The optimal geometry of nozzle cup is designed to get adjusted code dimensions on given distance
文摘Inter individual differences in the metabolism of antimalarials could be due to polymorphism of NAT2 gene. The authors determined the genotypic frequencies of single nucleotide polymorphism (SNP) of NAT2 gene and it's implication in antimalarial treatment during a vitamin A and zinc supplementation intervention in children aged 6 to 24 months. Children were deparasitized with artesunate-amodiaquine (ASAQ)-toddler 50/135 mg. Pharmacovigilance was done for 40 days, adverse events recorded and blood was spotted on filter paper for DNA extraction by chelex method. PCR-RFLP was performed with restriction enzymes KpnI, TaqI, and BamHl for detection of SNPs of NAT2. Allelic frequencies and phenotypes were compared between participants with or without adverse drug events. The prevalence of fast, slow and intermediate acetylators was 55%, 30% and 11% respectively. There was a significant association (P = 0.035) between NAT2 slow acetylators (and susceptibility to develop skin rash. No significant difference was observed between fast and slow acetylators and susceptibility to develop fever, anorexia, cough and common cold. Slow acetylators were more susceptible, (P = 0.011) to develop any adverse event The NAT2 slow acetylator phenotype was the most predominant and individuals with this phenotype were more significantly susceptible to develop adverse events to ASAQ.
文摘The effect of Batroxobin expression of neural cell adhesion molecule (NCAM) in left temporal ischemic rats with spatial memory disorder was investigated by means of Morri's water maze and immunohistochemical methods. The results showed that the mean reaction time and distance of temporal ischemic rats for searching a goal were significantly longer than those of sham-operated rats and at the same time NCAM expression of left temporal ischemic region was significantly increased. However, the mean reaction time and distance of Batroxobin-treated rats were shorter and they used normal strategies more often and earlier than those of ischemic rats. The number of NCAM immune reactive cells of Batroxobin-treated rats was more than that of ischemic group. In conclusion, Batroxobin can improve spatial memory disorder of temporal ischemic rats and the regulation of the expression of NCAM is probably related to the neuroprotective mechanism.
基金supported in part by programs of Qingdao Science and Technology Project (11-2-3-73-jh)Shandong Science and Technology Project (2011GSF 11815)Special Fund for Marine Scientific Research in the Public Interest (201005024)
文摘A rapid and sensitive fluorescence labeling method was developed and validated for the microanalysis of a sulfated polysaccharide drug,namely propylene glycol alginate sodium sulfate(PSS), in rat plasma. Fluorescein isothiocyanate(FITC) was selected to label PSS, and 1, 6-diaminohexane was used to link PSS and FITC in order to prepare FITC-labeled PSS(F-PSS) through a reductive amination reaction. F-PSS was identified by UV-Vis, FT-IR and 1H-NMR spectrum. The cell stability and cytotoxicity of F-PSS were tested in Madin-Darby canine kidney(MDCK) cells. The results indicated that the labeling efficiency of F-PSS was 0.522% ± 0.0248% and the absolute bioavailability was 8.39%. F-PSS was stable in MDCK cells without obvious cytotoxicity. The method was sensitive and reliable; it showed a good linearity, precision, recovery and stability. The FITC labeling method can be applied to investigating the absorption and metabolism of PSS and other polysaccharides in biological samples.
文摘In order to monitor the deformations of modern constructions a local 3D network was usually being established at the surrounding area. The centering error, of both the instrument and targets, causes significant uncertainties in the determination of the x, y, z coordinates of the network's points. In order to assure precise centering for both the instrument and targets, not only for the accessible but also for the inaccessible network's points, a prototype way of marking is being implied. A special semi-permanent portable metallic stand (Photo 1) was manufactured for marking the accessible points. The stand provides forced instrument centering of the order of_+0, lmm. It is light enough to carry, it accelerates and facilitates the centering and leveling of the instrument as well as it eliminates the time needed for the measurements. The applied laboratory checks in order to certify the suitability of its use and the provided accuracy are being described. For the inaccessible points special targets were used. The targets were put in permanent attachments (Photos 7-8), which were also manufactured. Useful conclusions were drawn when these special accessories were used in to a 3D network, which was established for the monitoring of a new football stadium. Two measurement phases were carried out. The first one is with the stadium empty and the second one is when it was crowded (about 32000 people) during a significant football match.
基金financially supported by National High Technology Research and Development Program of China(863 Program,Grant No.2007AA091603)
文摘Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(< 10 k Da at 24 h). In summary, HP-chitosan has excellent bioavailability and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.
文摘In the first two-thirds of The Golden Notebook (1962), the theme of the crack-up or breakdown is elaborated in the novels representation of national and global politics. Soviet-inspired communism, European colonialism and emperialism, Britain society, and national liberation struggles in the Third World are disintegrating, collapsing, crumbling, and fragmenting, under the pressures both internal and external. The last third of the novel relocates the crack-up in the person, [...], of Anna herself. In this paper, the author attempts to show that L The Golden Notebook on the central theme of "Breakdown, Fragmentation, and Disintegration", essing has written which shows that sometimes when people "crack-up", it is a way of self-healing. This theme finds an expression in the novel and this paper shows how Anna Wulf, the protagonist, tries to deal with her inner self-divisions, what part is played by each of Anna's four notebooks in her struggle to integrate her fragmented inner world and personality, what enables the notebooks to come together in the golden notebook at the end of the novel, and finally, how about her relationships to others, especially to Saul Green, contribute to her "crack-up" and "self-healing"