Objective: Cervical cancer is the second most common cancer among women worldwide, and over 85% of cervical cancers occur in developing countries such as China. Lack of resources for nationwide cervical cancer screening in China makes vaccination against oncogenic strains of HPV particularly important. Knowledge of age at sexual debut and sexual behavior is essential prior to implementation of a national vaccination program. Methods and materials: A cross-sectional epidemiologic survey was conducted across 21 urban and rural sites in China to assess age at sexual debut and sexual behavior. 98.6% of the 11,852 recruited women aged 15-59 years were included in the analysis. Data were collected using a short, nurse-administered questionnaire and analyzed using standard descriptive statistics and survival analysis. Results: In urban areas, more than ten percent of the 15-19 year old age group were already sexually active at the time of interview; this number increased to nearly 44% in the 20-24 year old age group. Chinese young women with an occupation were more likely to be sexually active compared to female students of the same age, irrespective of area of residence. The crude median sexual debut age for the youngest age group was 17 years, earlier than the sexual debut age reported by older cohorts. Younger age cohorts had an earlier menarche age than older cohorts and were more likely to have more sexual partners than older women, and more likely to have partners with more than one female partner. Conclusion: There is a trend towards earlier sexual debut and riskier sexual behaviors in younger age groups of Chinese women. These findings suggest that HPV vaccination of women between the ages of 13 and 15 years, before the completion of national compulsory education, is likely to contribute to the prevention of HPV infection and cervical cancer in China.

The silver(I) complex,[Ag(C(5)H(3)BrNO(3)S)](n), was obtained by reaction of AgNO(3) and 5-bromopyridine-3-sulfonic acid. The Ag(I) ion is coordinated by an O(3)N donor set in a slightly distorted tetra-hedral geometry. The Ag(I) ions are linked by μ(4)-5-bromo-pyridine-3-sulfonate ligands, forming a layer parallel to (100). The layers are further connected via C-H⋯Br hydrogen-bonding inter-actions into a three-dimensional supra-molecular network. The Ag⋯Ag separation is 3.0159 (6) Å, indicating the presence of argentophilic inter-actions.

Objective To determine whether aquaporin-4 (AQP4) regulates acute lesions, delayed lesions, and the associated microglial activation after cryoinjury to the brain. Methods Brain cryoinjury was applied to AQP4 knockout (KO) and wild-type mice. At 24 h and on days 7 and 14 after cryoinjury, lesion volume, neuronal loss, and densities of microglia and astrocytes were determined, and their changes were compared between AQP4 KO and wild-type mice. Results Lesion volume and neuronal loss in AQP4 KO mice were milder at 24 h following cryoinjury, but worsened on days 7 and 14, compared to those in wild-type mice. Besides, microglial density increased more, and astrocyte proliferation and glial scar formation were attenuated on days 7 and 14 in AQP4 KO mice. Conclusion AQP4 deficiency ameliorates acute lesions, but worsens delayed lesions, perhaps due to the microgliosis in the late phase.

G protein-coupled receptor 17 (GPR17), the new P2Y-like receptor, is phylogenetically related to the P2Y and cysteinyl leukotriene receptors, and responds to both uracil nucleotides and cysteinyl leukotrienes. GPR17 has been proposed to be a damage sensor in ischemic stroke; however, its role in brain inflammation needs further detailed investigation. Here, we extended previous studies on the spatiotemporal profiles of GPR17 expression and localization, and their implications for brain injury after focal cerebral ischemia. We found that in the ischemic core, GPR17 mRNA and protein levels were upregulated at both 12-24 h and 7-14 days, but in the boundary zone the levels increased 7-14 days after reperfusion. The spatiotemporal pattern of GPR17 expression well matched the acute and late (subacute/chronic) responses in the ischemic brain. According to previous findings, in the acute phase, after ischemia (24 h), upregulated GPR17 was localized in injured neurons in the ischemic core and in a few microglia in the ischemic core and boundary zone. In the late phase (14 days), it was localized in microglia, especially in activated (ED1-positive) microglia in the ischemic core, but weakly in most microglia in the boundary zone. No GPR17 was detectable in astrocytes. GPR17 knockdown by a small interfering RNA attenuated the neurological dysfunction, infarction, and neuron loss at 24 h, and brain atrophy, neuron loss, and microglial activation at 14 days after reperfusion. Thus, GPR17 might mediate acute neuronal injury and late microgliosis after focal cerebral ischemia.

Nicotinamide phosphoribosyltransferase (NAMPT) is a key enzyme in the salvaging pathway for the synthesis of nicotinamide adenine dinucleotide (NAD) that is involved in cell metabolism and proliferation. NAMPT is normally absent in astrocyte but highly expressed in glioblastoma, suggesting that it may promote cell survival through synthesizing more NAD. In this report, we evaluated the effect of APO866, a potent inhibitor of NAMPT against C6 glioblastoma. We found that APO866 inhibited the growth of C6 glioblastoma cells with IC(50) in nano-molar range. APO866 depleted intracellular NAD, caused marked inhibition of ERK activation and induced G2/M cell-cycle arrest. The effects by APO866 were abrogated by nicotinamide mononucleotide (NMN), the direct product of NAMPT. Administration of U0126, an ERK1/2 inhibitor, inhibited cell growth but displayed no synergistic effect with APO866. Taken together, our results indicated that APO866 is a potent growth inhibitor against glioblastoma through targeting NAMPT.

Many biochemical processes in the growth cone finally target its biomechanical properties, such as stiffness and force generation, and thus permit and control growth cone movement. Despite the immense progress in our understanding of biochemical processes regulating neuronal growth, growth cone biomechanics remains poorly understood. Here, we combine different experimental approaches to measure the structural and mechanical properties of a growth cone and to simultaneously determine its actin dynamics and traction force generation. Using fundamental physical relations, we exploited these measurements to determine the internal forces generated by the actin cytoskeleton in the lamellipodium. We found that, at timescales longer than the viscoelastic relaxation time of τ = 8.5 ± 0.5 sec, growth cones show liquid-like characteristics, whereas at shorter time scales they behaved elastically with a surprisingly low elastic modulus of E = 106 ± 21 Pa. Considering the growth cone's mechanical properties and retrograde actin flow, we determined the internal stress to be on the order of 30 pN per μm(2). Traction force measurements confirmed these values. Hence, our results indicate that growth cones are particularly soft and weak structures that may be very sensitive to the mechanical properties of their environment.

RATIONALE Inactivation of the p66Shc adaptor protein confers resistance to oxidative stress and protects mice from aging-associated vascular diseases. However, there is limited information about the negative regulating mechanisms of p66Shc expression in the vascular system. Objective: In this study, we investigated the role of SIRT1, a class III histone deacetylase, in the regulation of p66Shc expression and hyperglycemia-induced endothelial dysfunction. METHODS AND RESULTS Expressions of p66Shc gene transcript and protein were significantly increased by different kinds of class III histone deacetylase (sirtuin) inhibitors in human umbilical vein endothelial cells and 293A cells. Adenoviral overexpression of SIRT1 inhibited high-glucose-induced p66Shc upregulation in human umbilical vein endothelial cells. Knockdown of SIRT1 increased p66Shc expression and also increased the expression levels of plasminogen activator inhibitor-1 expression, but decreased manganese superoxide dismutase expression in high-glucose conditions. However, knockdown of p66Shc significantly reversed the effects of SIRT1 knockdown. In addition, p66Shc overexpression significantly decreased manganese superoxide dismutase expression and increased plasminogen activator inhibitor-1 expression in high-glucose conditions, which were recovered by SIRT1 overexpression. Moreover, compared to streptozotocin-induced wild-type diabetic mice, endothelium-specific SIRT1 transgenic diabetic mice had decreased p66Shc expression at both the mRNA and the protein levels, improved endothelial function, and reduced accumulation of nitrotyrosine and 8-OHdG (markers of oxidative stress). We further found that SIRT1 was able to bind to the p66Shc promoter (-508 bp to -250 bp), resulting in a decrease in the acetylation of histone H3 bound to the p66Shc promoter region. CONCLUSION Our findings indicate that repression of p66Shc expression by SIRT1 contributes to the protection of hyperglycemia-induced endothelial dysfunction.

Cysteinyl leukotrienes (CysLTs), potent inflammatory mediators, are released from ischemic brain, and may regulate ischemic injury through activating CysLT(1) and CysLT(2) receptors. The CysLT(1) receptor is closely associated with ischemic injury and post-ischemic repair; however, the CysLT(2) receptor-mediated responses remain unknown. Here, we investigated the spatiotemporal profiles and implications of CysLT(2) receptor expression and localization in rat brain after focal cerebral ischemia. CysLT(2) receptors were normally localized in astrocytes in the cortex and around the ventricles. After focal cerebral ischemia, CysLT(2) receptor expression was up-regulated in concert with neuronal and glial responses. In the acute phase (6-24 h), up-regulated CysLT(2) receptors were restricted to injured neurons in the ischemic core; while in the late phase (3-28 days), the up-regulation was restricted to hypertrophic microglia (ischemic core) and mainly localized in hypertrophic astrocytes (boundary zone). Thus, the spatiotemporal profiles of CysLT(2) receptor expression suggest that it plays regulatory roles in acute neuron injury, and astrocytosis and microgliosis in the late phase.

OBJECTIVE Recently, we reported that pranlukast, an antagonist of cysteinyl leukotriene receptor 1, attenuates ischemic injury in endothelial cells by decreasing reactive oxygen species (ROS) production and inhibiting nuclear factor-κB activation in a leukotriene-independent manner. In this study, we investigated the effect of pranlukast on oxidative stress injury induced by hydrogen peroxide (H2O2) in EA.hy926 cells, a human endothelial cell line, and the possible mechanisms. METHODS AND RESULTS We found that H2O2 reduced cell viability and increased lactate dehydrogenase release in a concentration- and time-dependent manner. Necrosis was the main death mode, and the necrotic rate increased 32% after exposure to 220 μM H2O2 for 4 hours. Pretreatment with pranlukast significantly ameliorated the reduced viability and the increased lactate dehydrogenase release and necrosis after exposure to H2O2. We next examined the mechanisms underlying the antinecrotic effects of pranlukast. The results showed that pranlukast attenuated excessive ROS production and ameliorated the reduced superoxide dismuase and glutathione peroxidase activity in EA.hy926 cells exposed to H2O2. Pranlukast also inhibited the collapse of mitochondrial membrane potential (MMP) induced by H2O2. Inhibition of ROS production by N-acetyl-l-cysteine, a powerful antioxidant, reduced MMP collapse and necrosis. Inhibition of MMP collapse by cyclosporine A, a mitochondrial permeability transition inhibitor, attenuated necrosis but failed to reduce ROS production. In addition, we found no expression of 5-lipoxygenase in EA.hy926 cells and zileuton, a 5-lipoxygenase inhibitor, did not affect the cellular injury induced by H2O2. CONCLUSION Pranlukast protects endothelial cells from H2O2-induced necrosis by inhibiting ROS-mediated collapse of mitochondrial membrane potential, and this is leukotriene-independent.

To determine the role of the phospholipase D (PLD) pathway in injury and survival of alveolar epithelial cells, A549 cells were exposed to H(2)O(2)(500 microM) which resulted in time-dependent injury and bi-phasic increase of PLD activity at 5 min and at 3 h, respectively. n-Butanol (0.5%) inhibited PLD activation, attenuated cell injury at 5 min of H(2)O(2) exposure, but enhanced injury at 3h of exposure. This activation was inhibited by treatment with catalase (500 units/ml). Exogenous phosphatidic acid mimicked the effects of PLD activation, and diphenyliodonium (NADPH oxidase inhibitor) reversed the decline in cell viability induced by H(2)O(2) exposure. Propranolol (phosphatidic acid phospholydrolase inhibitor) and quinacrine (phospholipase A2 inhibitor) had weak effects on H(2)O(2)-induced PLD activation but reversed H(2)O(2)-induced injury. We speculate that PLD activation at the initiation of H(2)O(2) exposure predominantly results in NAPDH oxidase activation, which mediates A549 cell injury, but turns to mediating cell survival as the H(2)O(2) attack continues, which might be mainly due to the accumulation of intracellular phosphatidic acid.