Induction of HSPA4 and HSPA14 by NBS1 overexpression contributes to NBS1-induced in vitro metastatic and transformation activity

<p>Abstract</p> <p>Background</p> <p>Nijmegen breakage syndrome (NBS) is a chromosomal-instability syndrome associated with cancer predisposition, radiosensitivity, microcephaly, and growth retardation. The NBS gene product, NBS1 (p95) or nibrin, is a part of the MRN complex, a central player associated with double-strand break (DSB) repair. We previously demonstrated that NBS1 overexpression contributes to transformation through the activation of PI 3-kinase/Akt. NBS1 overexpression also induces epithelial-mesenchymal transition through the Snail/MMP2 pathway.</p> <p>Methods</p> <p>RT-PCR, Western blot analysis, <it>in vitro </it>migration/invasion, soft agar colony formation, and gelatin zymography assays were performed.</p> <p>Results</p> <p>Here we show that heat shock protein family members, A4 and A14, were induced by NBS1 overexpression. siRNA mediated knockdown of HSPA4 or HSPA14 decreased the <it>in vitro </it>migration, invasion, and transformation activity in H1299 cells overexpressing NBS1. However, HSPA4 or HSPA14 induced activity was not mediated through MMP2. NBS1 overexpression induced the expression of heat shock transcription factor 4b (HSF4b), which correlated with the expression of HSPA4 and HSPA14.</p> <p>Conclusion</p> <p>These results identify a novel pathway (NBS1-HSF4b-HSPA4/HSPA14 axis) to induce migration, invasion, and transformation, suggesting the activation of multiple signaling events induced by NBS1 overexpression.</p

Hidden non-collinear spin-order induced topological surface states

Rare-earth monopnictides are a family of materials simultaneously displaying complex magnetism, strong electronic correlation, and topological band structure. The recently discovered emergent arc-like surface states in these materials have been attributed to the multi-wave-vector antiferromagnetic order, yet the direct experimental evidence has been elusive. Here we report the observation of non-collinear antiferromagnetic order with multiple modulations using spin-polarized scanning tunneling microscopy. Moreover, we discover a hidden spin-rotation transition of single-to-multiple modulations 2 K below the Neel temperature. The hidden transition coincides with the onset of the surface states splitting observed by our angle-resolved photoemission spectroscopy measurements. Single modulation gives rise to a band inversion with induced topological surface states in a local momentum region while the full Brillouin zone carries trivial topological indices, and multiple modulation further splits the surface bands via non-collinear spin tilting, as revealed by our calculations. The direct evidence of the non-collinear spin order in NdSb not only clarifies the mechanism of the emergent topological surface states, but also opens up a new paradigm of control and manipulation of band topology with magnetism.Comment: 32 pages, 4 figures, 10 extended figure

Influenza Pandemics: Past, Present and Future

Influenza A virus is well known for its capability for genetic changes either through antigen drift or antigen shift. Antigen shift is derived from reassortment of gene segments between viruses, and may result in an antigenically novel virus that is capable of causing a worldwide pandemic. As we trace backwards through the history of influenza pandemics, a repeating pattern can be observed, namely, a limited wave in the first year followed by global spread in the following year. In the 20th century alone, there were three overwhelming pandemics, in 1918, 1957 and 1968, caused by H1N1 (Spanish flu), H2N2 (Asian flu) and H3N2 (Hong Kong flu), respectively. In 1957 and 1968, excess mortality was noted in infants, the elderly and persons with chronic diseases, similar to what occurred during interpandemic periods. In 1918, there was one distinct peak of excess death in young adults aged between 20 and 40 years old; leukopenia and hemorrhage were prominent features. Acute pulmonary edema and hemorrhagic pneumonia contributed to rapidly lethal outcome in young adults. Autopsies disclosed multiple-organ involvement, including pericarditis, myocarditis, hepatitis and splenomegaly. These findings are, in part, consistent with clinical manifestations of human infection with avian influenza A H5N1 virus, in which reactive hemophagocytic syndrome was a characteristic pathologic finding that accounted for pancytopenia, abnormal liver function and multiple organ failure. All the elements of an impending pandemic are in place. Unless effective measures are implemented, we will likely observe a pandemic in the coming seasons. Host immune response plays a crucial role in disease caused by newly emerged influenza virus, such as the 1918 pandemic strain and the recent avian H5N1 strain. Sustained activation of lymphocytes and macrophages after infection results in massive cytokine response, thus leading to severe systemic inflammation. Further investigations into how the virus interacts with the host's immune system will be helpful in guiding future therapeutic strategies in facing influenza pandemics

Changes in preventive care utilisation and its influencing factors among Chinese adults before and after the healthcare reform: cross-sectional evidence from the China Health and Nutrition Survey in 2004-2015.

China launched its health reform in 2009. This study aimed to assess changes in preventive care utilisation (PCU) and its relationship with the healthcare reform. A cross-sectional study using demographic characteristics, socioeconomic status, environmental factors, and lifestyle and health status data of adults from five waves (2004-2015) of the China Health and Nutrition Survey (CHNS) was conducted. Multilevel mixed-effects logistic regression models were used. Data were derived from urban and rural communities of nine provinces in China. Data were obtained from five waves of the CHNS, with 9960 participants in 2004, 9888 in 2006, 10 286 in 2009, 9709 in 2011, and 10 628 in 2015. The primary outcome was PCU. PCU in 2004-2015 among adults was 3.29%, 3.13%, 3.77%, 4.95% and 2.73%, respectively. Whether before or after the health reform, having a history of disease and female gender were positive influencing factors of PCU. Before 2009, PCU was significantly associated with gender, income, medical insurance status and region. Age, medical insurance status, history of drinking and education level significantly affected PCU in 2009-2011. Having medical insurance was no longer a positive influencing factor of PCU, while high income had a negative effect on PCU, in 2011-2015. PCU from 2004 to 2015 was low and the health reform in China may lack sustainable effect on PCU. Further studies on how to ensure sustainability of PCU are necessary, and further reforms on preventive care services should be aimed at different ages, rural areas and participants without history of disease.This research was funded by the Chongqing Federation of Social Science Circles (no. 2017ZDYY24) and was supported by the Top Notch Talent Students’ programme of Chongqing Medical University (BJRC201804)

Surface Charge Induced Dirac Band Splitting in a Charge Density Wave Material (TaSe4)2I

(TaSe4)2I, a quasi-one-dimensional (1D) crystal, shows a characteristic temperature-driven metal-insulator phase transition. Above the charge density wave (CDW) temperature Tc, (TaSe4)2I has been predicted to harbor a Weyl semimetal phase. Below Tc, it becomes an axion insulator. Here, we performed angle-resolved photoemission spectroscopy (ARPES) measurements on the (110) surface of (TaSe4)2I and observed two sets of Dirac-like energy bands in the first Brillion zone, which agree well with our first-principles calculations. Moreover, we found that each Dirac band exhibits an energy splitting of hundreds of meV under certain circumstances. In combination with core level measurements, our theoretical analysis showed that this Dirac band splitting is a result of surface charge polarization due to the loss of surface iodine atoms. Our findings here shed new light on the interplay between band topology and CDW order in Peierls compounds and will motivate more studies on topological properties of strongly correlated quasi-1D materials.Comment: 18 pages, 4 figures. Comments are welcom

Application of Copper Electrochemical Deposition for the Metallization of Micropores

According to established routes for the microporous metallization of printed circuit boards (PCB), electroless copper plating using glyoxylic acid as a reducing agent and copper electroplating in a citrate bath were used for microporous metallization with PCB distributing micropores as a template. The results show that electroless copper plating using glyoxylic acid as a reducing agent and copper electroplating in a citrate bath can be successfully applied to the microporous metallization of PCB. After an electric conducting treatment of the micropores by electroless copper plating the copper deposited as fine grains and attached to the inner walls of the micropores. The copper deposit was also found in the loose grain arrangement and the leak plating area. Immediately after thickening treatment by copper electroplating, the resistance toward the copper coating of the inner wall decreased notably. The ratio of the copper electroplating rates at the inner and outer micropores was found to be 0.8:1.0. The copper electrodeposit fully covered the surface of the inner wall including the leak plating area, which means that the electroplated copper grains have a certain sideway growing ability. The copper coating on the inner wall was continuous, compact, and adhesive. This coating highly enhanced the conductivity of the interconnected PCB.National Natural Science Foundation of China[20873114, 20833005, 21021002]; National Key Basic Research Program of China[2009CB930703