Evidence of human papilloma virus infection and its epidemiology in esophageal squamous cell carcinoma

AIM： To look for the evidence of human papilloma virus （HPV） infection in esophageal squamous cell carcinomas （ESCC） and to investigate the potential role and epidemiology of HPV infection in the pathogenesis of esophageal carcinomas in Henan emigrants. METHODS： Papilloma virus （PV） and HPV were determined by UltrasensiveTM S-P immunohistochemistry （IHC） and in situ hybridization （ISH） in esophageal carcinoma tissues （82 cases） and the normal mucosa （40 cases）. RESULTS： IHC revealed that the positive rate of PV was 75.0%, 68.18% and 72.5% respectively while the HPV （16/18-E6） positive rate was 45.0%, 36.36%, 37.5%, respectively in esophageal carcinoma tissue specimens from Henan emigrants,the local citizens and patients in Hubei Cancer Hospital. The PV and HPV （16/18-E6） were negative in all normal esophageal mucosa specimens. No correlation was found between HPV in esophageal squamous cell carcinoma tissues and in grade 1-3 esophageal squamous cell carcinoma cells. In situ hybridization showed that the HPV （16/18） DNA positive rate was 30.0%, 31.8%, 25.0%, respectively in the 3 groups of samples. No positive hybridization signal was found in 40 normal esophageal mucosa specimens. The positive rate of HPV （16/18） DNA in the esophageal carcinoma specimens was significantly higher than that in normal mucosa specimens （P〈0.05）. The positive rate was not different among the 3 groups of esophageal carcinoma tissue specimens （P〉0.05）.CONCLUSION： HPV infection is high in esophageal carcinoma of Henan emigrants, local residents and patients in Hubei Cancer Hospital. HPV is closely related with esophageal squarnous cell carcinoma. HPV infection may play an important role in esophageal squarnous cell carcinoma.

Different coalescence sources of light nucleus production in Au-Au collisions at √sNN=3 GeV

We study the production of light nuclei in the coalescence mechanism of Au-Au collisions at midrapidity at √sNN=3GeV.We derive analytic formulas of the momentum distributions of two bodies,three bodies,and four nucleons coalescing into light nuclei and naturally explain the transverse momentum spectra of the deuteron(d),triton(t),helium-3(3He),and helium-4(4He).We reproduce data on the yield rapidity densities,yield ratios,and averaged transverse momenta of d,t,3He,and 4He and provide the proportions of contributions from different coalescence sources for t,3He,and 4He in their production.We find that besides nucleon coalescence,nucleon+nucleus coalescence and nucleus+nucleus coalescence may play requisite roles in light nucleus production in Au-Au collisions at √sNN=3 GeV.

Green Synthesis of Chemically Recyclable Polyesters via Dehydrogenative Copolymerization of Diols

Preparation of chemically recyclable polyesters by ring-opening polymerization(ROP)has made a considerable progress over the past few years.However,this method involves cumbersome synthesis and minimal functional diversity of cyclic monomers.Therefore,it is of great significance to develop novel polymerization methods for direct polymerization of commercially available monomers to prepare recyclable polyesters with versatile functionalities.In present work,we report dehydrogenative copolymerization of commercialα,ω-diols to afford high molecular weight chemically recyclable aliphatic copolyesters(65.7 kg·mol^(-1))by using commercially available Milstein catalyst precursor.The thermal properties of the obtained copolymers could be finely tuned by simply adjusting the feeding ratio of two monomers.The incorporation of aliphatic or aromatic rings into polyester mainchain via copolymerization of 1,10-decanediol with 1,4-cyclohexanedimethanol and 1,4-benzenedimethanol could significantly improve the thermal properties of the resulting copolymers.More importantly,the obtained copolyesters were able to completely depolymerize back to original diols via hydrogenation by the same catalyst in solvent-free and mild conditions,thus offering a green and cost-effective route toward the preparation of widely used polyesters.

Different production sources of light nuclei in ultra-relativistic heavy-ion collisions

We systematically study different production sources of light nuclei in ultra-relativistic heavy-ion collisions with a new method, an exclusive quark combination model + an inclusive hadron recombination model. We take deuterons and ~3 He produced in Pb-Pb collisions at ■= 2.76 TeV as examples to show the contribution of different production sources by studying their rapidity densities dN/dy, yield ratios and transverse momentum(PT)spectra just after hadronization and at the final kinetic freeze-out. We find that about a half of d and a fourth of ~3 He created just after hadronization can survive after the hadronic evolution process. Nucleons from A resonance decays make a much larger contribution to the regeneration of light nuclei at the hadronic phase stage, and this contribution is about 77% and 90% for d and ~3 He, respectively, calculated at the final kinetic freeze-out. In addition, we give an explanation for the constant behaviors of yield ratios d/p and ~3 He/p as a function of the averaged charged multiplicity in Pb-Pb collisions and also provide a possible explanation for the observation that d/p in Pb-Pb collisions is larger by a factor of about two than in pp collisions at LHC energies.