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This study presents new evidence on the relationship between dividend announcements and stock price responses, and provides a more comprehensive empirical analysis than that previously found in the literature. We simultaneously test several competing theories regarding the information content of dividends using two types of announcements: dividend initiations and specially designated dividends. The results of our analyses provide strong support for the single signal, cash-flow signalling hypothesis and only weak support for the John and Lang (1991) and multiple signal, cash-flow signalling model. Supporting evidence is also presented for the predictions of the free-cash flow hypothesis. (Reprinted by permission of the publisher.)

Insiders take their companies private to exploit their knowledge of the true value of the firms. Proof of this motivation is the pattern of abnormal net-buying engaged by insiders of companies taken private by management before the decision to go private is announced. This activity does not occur in companies taken private by a third party. Another proof is the inconsistency of the relationship between insider trading and the level of free cash as well as past tax liabilities.

In recent years, peroxisome proliferator-activated receptor-γ (PPARγ) activation by selective agonists has been emerged as a new and promising strategy for ovarian cancer therapy and prevention. Here, an integrated screening protocol that combined computational protein-ligand binding analysis and cell-based reporter-gene assay was performed against >180,000 biogenic compounds (primary and secondary metabolites) to discover novel potent PPARγ agonists. The screening integrated empirical non-binder exclusion, high-throughput molecular docking, fast affinity scoring, and molecular dynamics simulations to identify promising candidates. Consequently, 12 hits were tested in vitro, from which one and three compounds were found to have high and moderate agonistic potencies for PPARγ with EC values at nanomolar and micromolar levels, respectively. Structural bioinformatics analysis revealed a variety of chemical interactions, such as hydrogen bonds, van der Waals contacts, and hydrophobic forces at PPARγ complex interface with the newly identified agonists, conferring both high stability and strong specificity to PPARγ-agonist binding. [ABSTRACT FROM AUTHOR]

Evidence of significant insider selling prior to seasoned equity offering announcements is presented.

On the basis of analyzing the characteristics and the structure for a power transformer, the calculation model of main insulation electric field (EF) is established. Then, the numerical calculation and influencing factors analysis of the winding end electric field are done by using finite element calculation software. Thus the distribution of main insulation electric field and maximum electric field stress are obtained respectively. Through the comparison of calculation results and the insulation tests of products, the rationality of the calculation methods is examined mutually. Therefore, an efficient analysis method is provided for the insulation design of power transformer. [ABSTRACT FROM AUTHOR]

By using cis-3-hexenyl acetate as standard chemical, the electroantennogram (EAG) responses of Maruca testulalis (Lepidoptera, Pyralididae) to plant volatiles and sex pheromone were investigated. Both the males and the females of M. testulalis showed strong EAG responses to the volatiles, but no significant difference was observed under most test concentrations. Among the test nine plant volatiles, the males and females had greater difference in the shape of EAG response to trans-2-hexenal, and their maximum EAG relative response to high concentration trans-2-hexenal was 250% and 260%, respectively. No obvious EAG responses were observed to the cedrene and cedrol from cowpea Vigna unguiculata floral. Both the male and the female moths showed clear EAG responses to sex pheromone, and significant difference was detected between males and females. The maximum EAG relative response of the males to (E10, E12)-16 CHO, a main component of sex pheromone, was 250%, while that of the females was only 53%. The difference in the EAG responses between the males and females reflected the difference in the structure, function and behavior of the males and females olfactory system. [ABSTRACT FROM AUTHOR]

Documents persistent shifts in the relationship between stock returns and dividend yields over bull and bear markets. Nature of shift relative to the January effect; Distinction in the performance of dividend yield during each market; Use of time varying relationship between dividend yield and stock return in explaining results of earlier studies.

Puerariae Lobatae Radix (Gegen in Chinese) is the dried root of Pueraria lobata, a semiwoody, perennial, and leguminous vine native to China. Puerarin is one of the effective components of isoflavones isolated from the root of Pueraria lobata. Previous studies showed that extracts derived from the root of Pueraria lobata possessed antihypertensive effect. Our study is to investigate whether puerarin contributes to prevention of stroke by improving cerebral microcirculation in rats. Materials and Methods. Video microscopy and laser Doppler perfusion imaging on the pia mater were used to measure the diameter of microvessel and blood perfusion in 12-week old spontaneously hypertensive rats (SHRs) and age-matched normotensive WKY rats. Histological alterations were observed by hematoxylin and eosin staining, and microvessel density in cerebral tissue was measured by immunohistochemical analysis with anti-Factor VIII antibody. Cell proliferation was detected by [(3)H]-TdR incorporation, and activities of p42/44 mitogen activated protein kinases (p42/44 MAPKs) were detected by western blot analysis in cultured cerebral microvascular endothelial cells (MECs). Results. Intravenous injection of puerarin relaxed arterioles and increased the blood flow perfusion in the pia mater in SHRs. Puerarin treatment for 14 days reduced the blood pressure to a normal level in SHRs (P < 0.05) and increased the arteriole diameter in the pia mater significantly as compared with vehicle treatment. Arteriole remodeling, edema, and ischemia in cerebral tissue were attenuated in puerarin-treated SHRs. Microvessel density in cerebral tissue was greater with puerarin than with vehicle treatment. Puerarin-treated MECs showed greater proliferation and p42/44 MAPKs activities than vehicle treatment. Conclusions. Puerarin possesses effects of antihypertension and stroke prevention by improved microcirculation in SHRs, which results from the increase in cerebral blood perfusion both by arteriole relaxation and p42/44 MAPKs-mediated angiogenesis.

Objective: To estimate the associations of psychosocial factors with work-related musculoskeletal disorders (WMSDs), providing scientific evidence for targeted strategies for the prevention of WMSDs in Chinese coal miners., Methods: A total of 500 coal miners were consecutively enrolled to this cross-sectional study. The prevalence of WMSDs was assessed using the Standardized Nordic Questionnaire. Logistic regression analyses were conducted to estimate the associations between psychosocial factors and WMSDs., Results: Among coal miners, of 277 coal miners, 61% self-reported WMSDs in a 12-month period. Especially, back pain was the most frequent musculoskeletal symptom. WMSDs were statistically correlated with high job demands (OR = 1.3, 95%CI: 1.3 ∼ 3.5), low job control (OR = 1.6, 95%CI: 1.0 ∼ 2.4), low level of interpersonal relations (OR = 1.9, 95%CI: 1.2 ∼ 3.0) and low job satisfaction (OR = 1.6, 95%CI: 1.0 ∼ 2.4)., Conclusion: The results of this study demonstrate psychosocial factors were associated with WMSDs among coal miners, and psychosocial factors be considered for the prevention of WMSDs.

Objective: To explore the prevalence characteristics and influence factors related to occupation and individuals for musculoskeletal disorders of workers in Chinese mines., Methods: In a cross-sectional study of 1900 coal miners from a coal mine, the Standardized Nordic Questionnaire was used to assess the musculoskeletal disorders, and logistic regression analysis was performed to analyze the correlation between the occupational factor and he musculoskeletal disorders., Results: During the past year, 1205 miners of 1537 miners (78.4%) complained of the musculoskeletal disorders. The morbidity of lumbago was 59.5%. The morbidity of the musculoskeletal disorders in different body sites of the miners increased significantly with age (P < 0.05). The morbidity of the musculoskeletal disorders in the underground workers was significantly higher than that in the ground workers. According to logistic regression analysis, the repetitive operation and awkward posture were the risk factors for the musculoskeletal disorders in neck, shoulder and upper limbs; the repetitive operation, moving heavy substance and stooping posture were related significantly to lumbago; the musculoskeletal disorders in lower limbs were associated with the long standing and awkward posture., Conclusion: There is significant correlation between the occupational factors and the musculoskeletal disorders for coal miners.

Objective: To explore the influence of carbon dioxide pneumoperitoneum-laparoscopic surgery on tumor cell seeding and metastases in endometrial cancer., Methods: Twenty patients with endometrial cancer who underwent laparoscopic surgery and 10 patients with endometrial cancer who underwent laparotomic surgery were enrolled. Each patient was in preoperative clinical StageIand the uterus size in each patient was less than 12 weeks of pregnancy. Carbon dioxide pneumoperitoneum was established and maintained with CO2 insufflation at 4 approximately 6 L/min and intraperitoneal pressure of 13 mmHg with an automatic pneumoperitoneum machine. Cytologic examination of peritoneal fluid(at the beginning and end of the operation), CO2 filtrated gas and the lavage fluid of instruments during the laparoscopic surgery were performed. The protein expressions of E-cadherin,beta-catenin,P-selectin,matrix metalloproteinase-2(MMP-2),vascular endothelial growth factor (VEGF),and CD44v6 in tumor tissues before and after the operation were detected by DAKO Envision., Results: There were no case of positive washing cytology in the peritoneal fluid,CO2 filtrated gas, and the lavage fluid of instruments during the laparoscopic surgery. The expressions of E-cadherin and beta-catenin proteins were obviously abnormal in endometrial cancer. The abnormal expressions of E-cadherin and beta-catenin protein between the pre- and post-operations were not significantly different in both the laparoscopic group and the laparotomic group(P>0.05).The changes of abnormal expressions of E-cadherin and beta-catenin protein were no statistical difference between the two groups(P>0.05). The positive protein expressions of P-selectin,MMP-2,VEGF,and CD44v6 were not significantly different between the pre- and post-operations both in the laparoscopic group and the laparotomic group(P>0.05),and there was also no significant difference between the laparoscopic group and the laparotomic group(P>0.05).The follow-up period in the laparoscopic group was 7 approximately 19 (14.25+/-3.65) months and 7 approximately 19 (13.10+/-4.23) months in the laparotomic group. One patient got infection in the urinary system in the laparoscopic group and one patient had lower extremity venous thrombosis in the laparoscopic group.No recurrence was detected in both groups., Conclusion: Laparoscopic surgery for endometrial cancer has no effect on protein expressions of E-cadherin,beta-catenin,P-selectin,MMP-2,VEGF,and CD44v6 in tumor tissues. No evidence has been found that CO2 pneumoperitoneum-laparoscopic surgery may favor endometrial cancer cell seeding and metastases.

The present study was aimed to investigate the effect of ischemic postconditioning (I-postC) on ischemia/reperfusion (I/R) injury and whether calreticulin (CRT) is involved in its intracellular signal transduction both in vivo and in cultured skeletal muscle cells. I/R injury in the right hind limb of healthy male Wistar rats was induced by clamping the right femoral artery, and the rats were randomly divided into 3 groups (n=16): I/R group (4-hour ischemia/12- or 24-hour reperfusion), ischemic preconditioning (IPC) group (3 cycles of 1-minute ischemia/1-minute reperfusion) and I-postC group (3 cycles of 5-minute reperfusion/5-minute ischemia). The left hind limb was used as control. Lactate dehydrogenase (LDH) activity in blood plasma, wet/dry weight ratio (W/D) and ultramicrostructure of skeletal muscle were detected 12 h or 24 h after reperfusion. Cultured skeletal muscle cells from neonatal Sprague-Dawley (SD) rat were divided into 6 groups: hypoxia/reoxygenation (H/R) group, hypoxic postconditioning (H-postC) group, hypoxic preconditioning (HPC) group, cyclosporine A (CsA) + H-postC group, CsA + H/R group and control group. H/R was produced by 2-hour hypoxia/24-hour reoxygenation. The survival rate and apoptotic rate of skeletal muscle cells in each group were measured. Western blot was used to detect the expressions of CRT and calcineurin (CaN). The results were as follows: (1) During in vivo experiment, compared with I/R, I-postC significantly decreased LDH activity and W/D, attenuated the ultramicrostructure injury of skeletal muscle and the apoptosis of nucleolus. 12 h and 24 h after reperfusion, compared with that in I/R group, the expression of CRT in I-postC group increased by 439% and 102%, respectively (P<0.05), and the expression of CaN increased by 196% and 63%, respectively (P<0.05). Correlation analysis indicated a positive correlation between CRT and CaN expressions (r=0.865, P<0.01). (2) In cultured skeletal muscle cells, H-postC attenuated cell injury induced by H/R. Compared with those in H/R group, CRT and CaN expressions in H-postC increased by 31.8% (P<0.05) and 6.02%, respectively. The protection of H-postC and CaN up-regulation were eliminated when CsA, the inhibitor of CaN, was added before H-postC. Both in vivo and in vitro results indicate that I-postC, similar as IPC, can protect the skeletal muscle against I/R injury, and its effects may be mediated by CRT and CaN up-regulation. The inhibition of CaN expression may also attenuate the protective effects of I-postC.

Objective: To investigate if perlecan (PN) is involved in the myocardial protection of basic fibroblast growth factor (bFGF) in acute myocardial infarction., Methods: Twenty-four Wistar rats were randomized into 3 groups: myocardial infarction group (MI group, n = 8, undergoing ligation of the descending anterior branch of the left coronary artery), bFGF + MI group (n = 10, injected with bFGF into the border myocardium between the infracted and non- infracted areas immediately after the ligation of the descending anterior branch), and sham operation group (n = 6, undergoing sham operation and injection of normal saline). 24 h, 14 days, and 28 days after the operation the hemodynamic parameters, infarct size, and microvessel density (MVD) were observed. The hearts were taken out, RT-PCR was used to detect the mRNA expression of PN, and Western blotting was used to detect the expression of focal adhesion kinase (FAK) and p38 mitogen-activated protein kinase (MAPK) phosphorylation., Results: In the bFGF + MI group, the +dp/dt and -dp/dt were improved markedly, the infarct size was significantly smaller, the MVD value was higher than those of the MI group on day 14 and day 28; the perlecan mRNA expression was higher in the infarct marginal area and interior zone; and the expression of FAK and the p38MAPK phosphorylation were up-regulated in the marginal zone of the bFGF group., Conclusion: bFGF is useful in promoting ischemic myocardial angiogenesis; reducing the size of infracted myocardium, and improving the ventricular function in acute myocardial infarction. Perlecan participates in the cardiac protection induced by bFGF. The relevant pathway is related to up-regulation of FAK and p38MAPK.

To evaluate the significance of antithyroid antibodie levels, five hundred and twenty-six patients with thyroid diseases and 292 health subjects from Yuci District, Shanxi Province, China, were studied. Serum levels were determined for thyroid hormone receptor antibody (TRAb), microsomal antibody (TMAb) and thyroglobulin antibody (TGAb). Among patients, the percentages for nodular goiter and thyroid adenoma, Graves' disease, and Hashimoto's thyroiditis are 44.1%, 19.6% and 17.7%, respectively. The ratios of female to male were 2.0 to 15.6. Antibody-positive patients for TMAb, TGAb and TRAb were detectable as 94.6%, 76.3% and 20.4% for Hashimoto's thyroiditis, and 40.0%, 30.0% and 90.3% for Graves's disease. In conclusion, the high levels of the TRAb in Graves' disease, and those of the TGAb/TMAb in Hashimoto's thyroiditis and idiopathic hypothyroidism are meaningful for characterizing the epidemiological basis of the diseases and for using as prognostic indicators for the relapse in individual patients.

Both in vivo and cultured cardiomyocyte experiments were performed to investigate the alteration of expression of calreticulin (CRT) during the delayed cardioprotection induced by hypoxic preconditioning (HPC) and the intracellular signal transduction mechanisms of the alteration. (1) Wistar rats were randomly divided into three groups: sham operation group (Sham), myocardial infarction (MI) group induced by left coronary artery ligation and HPC+MI group (4-hour HPC 24 h before MI). Twenty-four hours, 14 d and 28 d after left coronary artery ligation, myocardial function, infarction size and the area at risk were measured. Western blot was used to detect the expression of CRT, the activity of p38 mitogen-activated protein kinase (MAPK) and stress-activated protein kinase (SAPK). (2) Cultured cardiomyocytes from neonatal Sprague-Dawley (SD) rat were divided into six groups: hypoxia/reoxygenation (H/R), HPC, HPC+H/R, p38 MAPK inhibitor SB203580+HPC+H/R (SB+HPC+H/R), SAPK inhibitor SP600125+HPC+H/R (SP+HPC+H/R) and control. Survival rate and apoptosis rate of cardiomyocytes 6 h after H/R and activities of lactate dehydrogenase (LDH) in culture medium in each group were measured. Western blot was used to detect the expression of CRT and activities of p38 MAPK and SAPK. The results are as follows: (1) During in vivo experiment, compared with MI group, HPC significantly improved +dp/dt(max) and -dp/dt(max), reduced infarction size and the area at risk. HPC dramatically changed the expression of CRT. CRT expression in HPC+MI group was 206% of that in MI group (P<0.05) 24 h after infarction, especially in the area at risk. However, 28 d after operation, the expression of CRT decreased by 57%. Correlation analysis indicated a positive correlation between CRT expression and myocardial function (r=0.9867, P<0.05), and negative correlation between CRT expression and infarction size (r=-0.9709, P<0.05). (2) In cultured cardiomyocytes, HPC attenuated cell injury induced by H/R. CRT expression increased moderately to 222% of control (P<0.05) during HPC, but increased dramatically to 503% of control (P<0.05) after H/R. HPC reduced H/R-induced CRT up-regulation to 56% of that in H/R group (P<0.05). Correlation analysis indicated that CRT expression induced by HPC had a positive correlation with p38 MAPK activity (r=0.9021, P<0.05), but a negative correlation with SAPK activity (r=-0.8211, P<0.05). Both in vivo and in vitro results indicate that HPC protects myocardium from ischemia or H/R injury. p38 MAPK is possibly involved in the up-regulation of CRT induced by HPC, while SAPK has a negative influence.

Objective: To explore the effect of simvastatin on the cell cycle and caspase-3 expression in human omental preadipocytes., Methods: The preadipocytes were randomly divided into a blank group, a 10(-5) mol/L simvastatin group, and a 10(-4) mol/L simvastatin group. Each group was incubated with different concentrations of simvastatin for 48 hours. MTT method was used to analyze the effect of simvastatin on the proliferation. Distribution of the cell cycle was measured by flow cytometric. Caspase-3 expression was examined by cyto- immunochemistry., Results: After being induced to differentiate for 16 days the human omental preadipocytes developed to mature adipocyte penotypes with lipid droplet. Simvastatin 10(-4) mol/L had significant anti-proliferation effect. Flow cytometric analysis showed the cell cycle was blocked in G0/G1 phase and caspase-3 positive cells increased dramatically., Conclusion: Simvastatin may block the cells in G0/G1 phase, and induce caspase-3 expression, which may trigger apoptosis.

Objective: To investigate the inhibition of HPV18E6 gene in HeLa cell transfected with plasmid expressing human papilloma virus 18 E6 (HPV18E6) short hairpin RNA (shRNA)., Methods: We synthesized two HPV18E6 shRNA frames and sub-cloned them into pSUPER which can express shRNA in mammalian cells to construct pE6-1shRNA and pE6-2shRNA which were mutant in E6 shRNA frame. The pE6-1shRNA, pE6-2shRNA and pcDNA3.1 were co-transfected into HeLa cells by cationic liposome respectively and the positive transfectants were selected by G418. The HPV18E6 mRNA and protein expression level was detected by semi-quantitative RT-PCR and streptavidin-peroxidase conjugated method (SP) to assay the inhibitory effects of pE6shRNA., Results: We successfully constructed several new HeLa cell lines transfected with pE6-1shRNA and pE6-2shRNA. In the HeLa cells without transfection and the HeLa cells transfected with pE6-1shRNA plasmid, the HPV18E6 mRNA levels were 1.14 +/- 0.45, 0.76 +/- 0.28 respectively, and the difference of HPV18E6 mRNA levels was significant (P < 0.05). The inhibition efficiency of HPV18E6 gene mRNA was 33.3% and the HPV18E6 protein levels were declined after transfection with pE6-1shRNA. In the HeLa cells transfected with pE6-2shRNA and pSUPER plasmids, HPV18E6 mRNA and protein expression levels were not different from those in wild HeLa cells., Conclusions: The pE6-1shRNA plasmid can inhibit HPV18E6 expression in HeLa cells, which is persistent, specific and heritable.

Objective: To investigate the quantities of human papillomavirus (HPV) 16 E6 gene and to study its relationship with the expression of survivin in cervical carcinoma., Methods: In 148 patients including cervical intraepithelial neoplasia (CIN), cervical carcinoma and chronic cervicitis, the quantities of HPV 16 E6 gene were detected by semiquantitative polymerase chain reaction (PCR); and the expressions of survivin were measured by immunohistochemical streptavidin-biotin peroxidase (SP) assay., Results: The quantities of HPV 16 E6 gene were 0.3 +/- 0.4, 0.6 +/- 0.4, 1.8 +/- 0.6 and 2.4 +/- 0.6, and expression rates of survivin were 7%, 31%, 63% and 84% respectively in chronic cervicitis, CIN I, CIN II-III and cervical cancer tissues. The quantities of HPV 16 E6 gene and the expressions of survivin tended to increase along with the tumor progression (P < 0.05). The quantities of HPV16 E6 gene and the expressions of survivin of CIN I, II-III or cervical cancer were significantly higher than that of chronic cervicitis or CIN I (P < 0.01). Positive rank correlation between the quantities of HPV16 E6 gene and the expression of survivin was observed in cervical carcinoma (gamma(s) = 0.62, P < 0.05)., Conclusions: The quantities of HPV16 E6 gene appear to be associated with an increased risk of developing cervical cancer. Survivin overexpression might play an important role in the process of cervical carcinoma.

Objective: To investigate the effect of HPV16E6 DNA vaccines on inducing the antitumor immune response to cervix carcinoma in vivo., Methods: We prepared pCB/HPV16E6 DNA vaccines to prevent and treat 615 modle mice transplanted E6 + U14 in vivo respectively. Survival and tumor sizes of all mice were recorded and their lymphnodes and lung's metastases were detected by microscopic observation. The cytotoxicity of the spleen T cells of those mice immuned with HPV E6 DNA vaccines against the E6 U14 and U14 was detected by MTT assay., Results: HPV16 E6 DNA vaccines prevented the transplanted tumor growth effectively in inbred strain mice and cured some tumor-bearing mice (P < 0. 001). Pathological results showed that the number of lymphodes with metastases foci decreased in the preventing group (P < 0.05). HPV16 E6 DNA vaccines induced special and higher cytotoxicity T lymphocytes against the E6 + U14 (P < 0.001)., Conclusion: HPV16 E6 DNA vaccines can induce antitumor immune protection of the mice against E6 + U14 cells, suggesting that the vaccines may be effective in preventing and treating cervix cancer after an operation.

Aim: To investigate the effects of human urotensin II (hUII) on in vivo pia mater microcirculation in rats., Methods: Adult SD rats were randomly assigned to the following groups: control, sodium chloride injection (NS), UII(10(-6) mol/L), noradrenaline (NA, 10(-6) mol/L), and UII (10(-6) mol/L) + NA (10(-6) mol/L) groups. For recording of microcirculation images in pia mater, skull windows were performed and mounted on the stage of an intravital microscope equipped with a TV camera. Video images of microcirculation were stored by a video cassette recorder. Temporal changes in internal diameter and microcirculatory velocity of microvessels were measured by computer using the Image Pro software. The blood flow in cerebral tissues were measured with PIMII laser Doppler perfusion Imager (Lisca, Sweden)., Results: The internal diameters of arterioles and venules in control group were (35.4 +/- 3.6) microm and (40.6 +/- 8.5) microm, respectively. In UII group, the arterioles and venules contracted immediately after treated with UII and up to the peak at 1 min, the internal diameters of arterioles and venules were (25.6 +/- 3.4) microm and (23.4 +/- 3.3) microm, respectively (P < 0.05). Both microcirculatory velocity in arterioles and venules had no significant changes in UII group (P > 0.05). The blood flow in meninges increased 1 min after treated with UII and up to high peak at 5 min (3.5 +/- 0.4 perfusion unit vs. control 2.3 +/- 0.6, P < 0.05)., Conclusion: hUII can contract microvessels in pia mater of rats and increase microcirculatory blood perfusion to cerebral tissue involved.

Objective: To detect the expression of transforming growth factor-beta 1(TGF-beta 1) in epithelial neoplasms and its clinicopathologic features and prognosis., Methods: TGF-beta 1 expression was detected in 77 cases of epithelial ovarian neoplasms by SABC immunohistochemistry (including 21 benign tissues, 7 borderline tissues, and 49 epithelial ovarian cancer tissues), and they were compared with 14 normal ovarian tissues., Results: 1. The positive rate of TGF-beta 1 expression was 71.42% in the normal ovary, 76.19% in benign tissues, 4/7 in borderline tissues and 38.78% in epithelial ovarian cancer tissues. 2. TGF-beta 1 expression was associated with the grade, the FIGO stage, and the histologic type of the patients with epithelial ovarian cancer (P < 0.05)., Conclusion: The expression of TGF-beta 1 may play an important role in the progression of epithelial ovarian cancer and may be related to the prognosis of epithelial ovarian cancers.