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This work investigates the effects of interlayer hybrid fiber dispersion on the impact response of carbon-flax epoxy hybrid laminates at low carbon volume fractions, and benchmarks the mechanical performance enhancement against the non-hybrid flax epoxy. Five hybrid laminate stacking sequences with similar carbon-to-flax weight ratio were fabricated and subjected to low-velocity impact at three different energy values, generating non-perforated and perforated damage states. A virtual drop-weight impact test that models intralaminar failure based on continuum damage mechanics approach, and delamination using cohesive elements, was also implemented to evaluate the material behavior and damage development in the composites. Simulation results were then verified against experimental data. Results suggested that positioning stiffer carbon plies at the impact face does not necessarily lead to enhancement of the hybrid's impact properties. On the contrary, flax plies at the impacted side lead to significant improvement in impact resistance compared to the non-hybrid flax composite with similar thickness. Results of finite element analysis showed that carbon plies play a significant role in the hybrid laminate's energy absorption characteristics due to lower failure strain. [ABSTRACT FROM AUTHOR]

Background and Purpose: The effects of 4-O-methylhonokiol (MH), a constituent of Magnolia officinalis, were investigated on human prostate cancer cells and its mechanism of action elucidated.Experimental Approach: The anti-cancer effects of MH were examined in prostate cancer and normal cells. The effects were validated in vivo using a mouse xenograft model.Key Results: MH increased the expression of PPARγ in prostate PC-3 and LNCap cells. The pull-down assay and molecular docking study indicated that MH directly binds to PPARγ. MH also increased transcriptional activity of PPARγ but decreased NF-κB activity. MH inhibited the growth of human prostate cancer cells, an effect attenuated by the PPARγ antagonist GW9662. MH induced apoptotic cell death and this was related to G(0) -G(1) phase cell cycle arrest. MH increased the expression of the cell cycle regulator p21, and apoptotic proteins, whereas it decreased phosphorylation of Rb and anti-apoptotic proteins. Transfection of PC3 cells with p21 siRNA or a p21 mutant plasmid on the cyclin D1/ cycline-dependent kinase 4 binding site abolished the effects of MH on cell growth, cell viability and related protein expression. In the animal studies, MH inhibited tumour growth, NF-κB activity and expression of anti-apoptotic proteins, whereas it increased the transcriptional activity and expression of PPARγ, and the expression of apoptotic proteins and p21 in tumour tissues.Conclusions and Implication: MH inhibits growth of human prostate cancer cells through activation of PPARγ, suppression of NF-κB and arrest of the cell cycle. Thus, MH might be a useful tool for treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

Background and Purpose The effects of 4- O-methylhonokiol ( MH), a constituent of Magnolia officinalis, were investigated on human prostate cancer cells and its mechanism of action elucidated. Experimental Approach The anti-cancer effects of MH were examined in prostate cancer and normal cells. The effects were validated in vivo using a mouse xenograft model. Key Results MH increased the expression of PPARγ in prostate PC-3 and LNCap cells. The pull-down assay and molecular docking study indicated that MH directly binds to PPARγ. MH also increased transcriptional activity of PPARγ but decreased NF- κB activity. MH inhibited the growth of human prostate cancer cells, an effect attenuated by the PPARγ antagonist GW9662. MH induced apoptotic cell death and this was related to G0- G1 phase cell cycle arrest. MH increased the expression of the cell cycle regulator p21, and apoptotic proteins, whereas it decreased phosphorylation of Rb and anti-apoptotic proteins. Transfection of PC3 cells with p21 si RNA or a p21 mutant plasmid on the cyclin D1/ cycline-dependent kinase 4 binding site abolished the effects of MH on cell growth, cell viability and related protein expression. In the animal studies, MH inhibited tumour growth, NF- κB activity and expression of anti-apoptotic proteins, whereas it increased the transcriptional activity and expression of PPARγ, and the expression of apoptotic proteins and p21 in tumour tissues. Conclusions and Implication MH inhibits growth of human prostate cancer cells through activation of PPARγ, suppression of NF- κB and arrest of the cell cycle. Thus, MH might be a useful tool for treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

Cancer is primarily a disease of older adults. However, little data is available on the clinical features of cervical cancer in elderly patients. We investigated the trends in incidence and clinical features associated with cervical cancer among the elderly in Korea during the period of 1993-2002. We obtained data from the National Cervical Cancer Incidence Database, which was constructed in collaboration with the Korea Central Cancer Registry (KCCR) and Korea Gynecologic Cancer Registry (KGCR). A total of 44 191 women with cervical cancer were diagnosed between 1993 and 2002. Patients were divided into three groups based on age: /=70 years (Group 3). During this period, upward incidence trends were noted in Group 3 while constant and downward incidence trends were noted in Groups 1 and 2, respectively. Pooled analysis across years revealed that squamous cell carcinoma and advanced stage (IIB, III, and IV) were more common in Group 3 than in Groups 1 and 2. With regard to primary treatments in the elderly patients, surgery appeared to be performed increasingly despite the fact that advanced stage (IIB, III, and IV) was more common in Group 3 than in Groups 1 and 2. Our findings suggest that the incidence of cervical cancer in the elderly is increasing in Korea, while it is decreasing overall. The current health service must emphasize education for the elderly about cervical cancer prevention while concentrating on screening. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Asian Indian men are reported to have a higher incidence of coronary heart disease than men of other ethnic groups worldwide. Among the many hypotheses, one possible risk factor may be related to their dietary habits. This study estimated the plasma concentrations of fatty acids, antioxidant vitamins, and selenium in Indians and Chinese of Singapore. METHODS: The study population consisted of 145 Indian men and 147 Chinese men ages 26 to 79 y from a cross-sectional survey, the National University of Singapore Heart Study. RESULTS: Our findings indicated that Indians had lower plasma concentrations of docosahexanoic acid (3.07% versus 3.54%, P < 0.001), alpha-linolenic acid (0.48% versus 0.57%, P < 0.001), and total omega-3 fatty acids (4.71% versus 5.27%, P < 0.001) than did the Chinese. Arachidonic acid was higher in Indians (4.83%) than in the Chinese (4.51%, P = 0.007). The ratio of omega-3 acid to omega-6 fatty acid was also lower in Indians (0.15) than in the Chinese (0.16, P = 0.007). There were no significant differences in the concentrations of monounsaturated fatty acids, but saturated fatty acids were higher in Indians (39.17%) than in the Chinese (38.28%, P < 0.001). Analysis of vitamins A, C, and E showed no significant differences between Indians (0.67, 5.72, and 13.04 mg/L, respectively) and Chinese (0.68, 6.48, and 12.71 mg/L, respectively); however, serum concentration of selenium in Indians (117.49 microg/L) was significantly lower than in the Chinese (126.72 microg/L, P < 0.001). CONCLUSION: The results suggest that lower plasma concentrations of omega-3 fatty acids and selenium and higher concentrations of arachidonic acid and saturated fatty acids in Indians may reflect lower intakes of marine foods and, as a consequence, higher susceptibility to coronary heart disease. [ABSTRACT FROM AUTHOR]

Objectives: To quantify the improvement in health outcomes in patients after total knee replacement (TKR).Methods: This was a two-year non-randomized prospective observational study in knee osteoarthritis (OA) patients undergone TKR. Patients were interviewed one week before, six months after, and two years after surgery using a standardized questionnaire including the SF-36, the Oxford Knee Score (OKS), and the Knee Society Clinical Rating Scale (KSS). A generalized estimating equation (GEE) model was used to estimate the magnitudes of the changes with and without the adjustment of age, ethnicity, BMI, and years with OA.Results: A total of 298 (at baseline), 176 (at six-months), and 111 (at two-years) eligible patients were included in the analyses. All the scores changed significantly over time, with the exception of SF-36 social functioning, vitality, and mental health. With the adjustment of covariates, the magnitude of changes in these scores was similar to those without the adjustment.Conclusions: Both general and knee-specific physical functioning had been significantly improved after TKR, while other health domains have not been substantially improved after the surgery. [ABSTRACT FROM AUTHOR]