Environmental pollution is closely linked to the occurrence and development of cancer. Chemical carcinogens are the most important environmental factors causing cancer in humans. Among them, persistent organic pollutants (POPs) are characterized by their widespread distribution, persistence, and bioaccumulation. Research on the carcinogenic effects of POPs has received considerable attention in recent years. This article reviewed the internal exposure, association with cancer risk, and potential carcinogenic mechanisms of five typical classes of POPs in the environment, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), per- and poly-fluoroalkyl substances (PFAS), brominated flame retardants (BFRs), and short-chain chlorinated paraffins (SCCPs). These five types of POPs have distinct carcinogenic mechanisms, including interfering with cell proliferation cycle, altering epigenetic inheritance, promoting oxidative stress, altering energy metabolism, and affecting immune function. The development of cancer is the result of interaction between intrinsic genetic factors and external environmental factors. In addition to focusing on how environmental POPs affect the genetic material of organisms, it is also important to consider their effects on the tumor microenvironment, including tumor immunity and angiogenesis. Understanding these effects is crucial for guiding future efforts in pollution control and precision medicine in cancer treatment.

BACKGROUND:Studies have shown that both Panax notoginseng saponins and concentrated growth factor can promote fracture healing,but there are few studies addressing their combined effects on fracture healing.Panax notoginseng saponins may accelerate fracture healing by promoting the release of concentrated growth factor-related factors over a certain period of time. OBJECTIVE:To study the effect of Panax notoginseng saponins on concentrated growth factor release and fracture healing in rats. METHODS:Eighteen 8-week-old Sprague-Dawley rats were numbered and randomly divided into three groups:Panax notoginseng saponins group,model control group and blank group.Panax notoginseng saponins group was fed with Panax notoginseng saponins for 2 weeks.Model control group was given 2 mL of normal saline for 2 weeks and blank group was fed normally.Concentrated growth factor was obtained by the centrifugation method both from the Panax notoginseng saponins group and model control group.After 1 week of normal feeding,all animals underwent modeling for femoral fracture.The Panax notoginseng saponins group and the model control group were implanted with autologous concentrated growth factor,and then the release concentration of growth factors at different time points(1 hour,1,3,5,7,9 and 11 days)were measured by ELISA.Fracture healing was assessed based on postoperative X-ray and hematoxylin-eosin staining of bone tissues. RESULTS AND CONCLUSION:Compared with the model control group,the Panax notoginseng saponins group had higher release concentrations of vascular endothelial growth factor A and transforming growth factor β at 7,9,and 11 days,Platelet-derived growth factor BB at 5,9,and 11 days,and basic fibroblast growth factor at 1-11 days(P<0.01).X-ray examinations indicated that fracture healing in the Panax notoginseng saponins group was better than that in the model control group,and fracture healing in these two groups was better than that in the blank group at 2 months after surgery.Hematoxylin-eosin staining results found that the constituent osteocyte density in the Panax notoginseng saponins group was greater than that in the model control group,and the constituent osteocyte density in these two groups was better than that in the blank group.These findings indicate that Panax notoginseng saponins can increase the concentration of concentrated growth factor-related factors.After intervention with Panax notoginseng saponins,concentrated growth factors are more advantageous in promoting fracture healing in rats.

Abstract： Objective　To elucidate the antigenic antibody reaction of recombinant expression of non-structural protein 1 (NS1) of Japanese encephalitis (JE) virus with various mosquito-borne flaviviruses, including JE virus, and the antigenic antibody reaction of serum samples of patients infected with JE virus in acute stage. Methods　In this study, Escherichia coli prokaryotic expression vector (pET) system was used to recombinant express Japanese encephalitis virus NS1 gene. Western Blot assay was performed to detect the antibody responses of the recombinantly expressed protein against a variety of mosquito-transmitted flaviviruses, including JE virus, as well as antigen-antibody reactions of serum from patients with acute JE virus infection. Results　The NS1 gene expression product of JE virus (P3 strain) was in the form of an inclusion body, and the denatured and renatured expression product was displayed as a single band in the denatured gel (polyacrylamide gel electrophoresis, PAGE), with a molecular weight of about 45 000. The results of further antigen-antibody analysis showed that the antigen/antibody hybridization reaction of the expression product with polyclonal or monoclonal antibody of JE virus (mosquito isolates, encephalitis isolates) and serum samples of patients with acute JE virus infection could be completely consistent. The recombinant product showed negative antigen/antibody hybridization reactions with mosquito-transmitted flaviviruses, such as dengue virus and yellow fever virus polyclonal antibodies, but positive reactions with polyclonal antibodies to West Nile virus and Murray Valley encephalitis virus. Conclusions　In this study, the recombinant expression of the NS1 protein of JE virus was successfully obtained, and the antigen/antibody reaction between the recombinant protein and samples of patients infected with mosquito-borne flavivirus and JE virus was analyzed. The study results provide important basic data for elucidating the antigen-antibody reaction between the NS1 protein of JE virus and mosquito-borne flavivirus. The recombinant expression protein obtained in this study provides an important material basis for further research on the function of JE virus NS1 protein.

Thioredoxin reductase (TrxR) is one class of the most important antioxidant selenoproteins and is involved in regulating tumor genesis and progression. It has been reported that naphthoquinones can target and inhibit TrxR1 activity therefore produce reactive oxygen species (ROS) mediated by TrxR1, resulting into cellular redox imbalance and making the naphthoquinone compounds to become potential antitumor chemotherapy drugs. The purpose of this work is to explore the interaction between TrxR1 and menadione using biochemical and mass-spectrometric (MS) analyses, to further reveal the detailed mechanisms of TrxR1-mediated naphthoquinone reduction and inhibition of TrxR1 by naphthoquinone compounds. Using the site-directed mutagenesis and recombinantly expressed TrxR1 variants, we measured the steady-state kinetic parameters of menadione reduction mediated by TrxR1 and its variants, performed the inhibition analysis of menadione on TrxR1 activity, and eventually identified the interaction between menadione and TrxR1 through MS analysis. We found that Sec-to-Cys mutation at residue of 498 significantly enhanced the efficiency of TrxR1-mediated menadione reduction, though the Sec⁴⁹⁸ is capable to catalyze the menadione reduction, indicating that TrxR1-mediated menadione reduction is dominantly in a Se-independent manner. Mutation experiments showed that Cys⁴⁹⁸ is mainly responsible for menadione catalysis in comparison to Cys⁴⁹⁷, while the N-terminal Cys⁶⁴ is slightly stronger than Cys⁵⁹ regarding the menadione reduction. LC-MS results detected that TrxR1 was arylated with one molecule of menadione, suggesting that menadione irreversibly modified the hyper-reactive Sec residue at the C-terminus of selenoprotein TrxR1. This study revealed that TrxR1 catalyzes the reduction of menadione in a Se-independent manner meanwhile its activity is irreversibly inhibited by menadione. Hereby it will be useful for the research and development of naphthoquinone anticancer drugs targeting TrxR1.
Catalysis ; Drug Development ; Oxidation-Reduction ; Thioredoxin Reductase 1/metabolism* ; Vitamin K 3/metabolism*

Objective To study the antigen-specific immune response induced by the graphene oxide (GO) in mice.Methods OVA-loaded GO nano-immunocomplexes (GO-OVA) were prepared by co-incubation of nano GO with model antigen ovalbumin (OVA).Nano GO was characterized by atomic force microscopy and laser particle sizeanalyzer.The cytotoxicity of GO to mouse bone marrow dendritic cells (BMDCs) was detected by cell counting kit (CCK-8).The GO-OVA uptake of BMDCs were observed by fluorescent staining.C57BL/6 mice were divided into OVA group,aluminum adjuvant OVA (Al-OVA) group and GO-OVA group (6 mice in each group) by body weight for in vivo immunization.The levels of OVA-specific antibody IgG (total IgG,IgG1,and IgG2a) in serum of mice were detected by enzyme-linked immunosorbent assay (ELISA).The T lymphocyte subsets in spleen and inguinal lymph nodes of mice were detected by flow cytometry.Results The average particle size of the prepared nano GO was (294.34±4.68) nm,and the polydispersity coefficient was 0.208.Nano GO has less toxicity to mouse BMDCs.The results of in vitro experiments indicated that GO-OVA nanovaccine can be efficiently internalized by mouse BMDCs.The antigen-specific IgG antibodies induced by the GO-OVA was similar to that of aluminum adjuvant and the difference was not statistically significant (P＞0.05),and the Th1-type response was predominant.The proportions of CD4+ and CD8+ T lymphocytes in the spleen and inguinal lymph nodes in GO-OVA group were significantly higher than those in OVA and Al-OVA groups,and the differences were statistically significant (all P＜0.05).Conclusions GO-OVA nano-immunocomplexes can induce both humoral and cellular immune responses in mice,which provides basis for the development of novel vaccine vectors and adjuvants.

Objective To study the maturation and activation effects of hyaluronic acid (HA) modified polymer nanoparticles co-delivering adjuvants and antigens on mouse bone marrow dendritic cells (BMDCs). Methods HA-modified polylactic acid-glycolic acid copolymer (PLGA) and cationic lipid DOTAP were used as nanocarriers (DOTAP-PLGA) to co-deliver adjuvant CpG with model antigen ovalbumin (OVA). In the drug-loaded nanocarriers, CpG was covalently bound to the surface of HA, and OVA was physically blended into DOTAP-PLGA nanocarriers. The nanoparticles were characterized by transmission electron microscopy and dynamic light scattering. The in vitro release of CpG and OVA in the nanoparticles was investigated. The uptake and distribution of nanoparticles in mouse BMDCs were studied by flow cytometry and laser scanning confocal microscopy. The maturation and cytokine expression of mouse BMDCs were evaluated by flow cytometry and enzyme-linked immunosorbent assay, respectively. Results The CpG-HA-OVA-PLGA nanoparticles loading CpG and OVA were prepared. The average particle size was (305.1±2.2) nm and the polydispersity index was 0.203. A core-shell structure of the nanoparticles modified by HA was clearly observed by transmission electron microscopy. Cellular experiment results showed that CpG-HA-OVA-PLGA nanoparticles could be efficiently uptaken by mouse BMDCs, and promote lysosomal release of CpG and cytoplasmic delivery of antigen OVA. Compared with free OVA group and free OVA+CpG group, the CpG-HA-OVA-PLGA nanoparticles significantly up-regulated the expression of co-stimulatory molecules CD86 and CD40 (all P<0.01), major histocompatibility complex I (MHC-I) (P<0.01), and cytokine tumor necrosis factor-α (TNF-α) (P<0.01). Conclusions HA-modified CpG and OVA nanoparticle co-delivery vectors can effectively promote the maturation and activation of dendritic cells, which provides a basis for the development of novel vaccine vectors for the co-delivery of antigens and adjuvants.

At present,the AIDS epidemic situation in college students is becoming more and more serious.In view of the particularity of colleges students and the lack of professional team for AIDS prevention and control in colleges and universities,there exists ethical issues when carry out the prevention and control for AIDS in colleges and universities such as the ethical issue in publicity and education,the ethical issue in AIDS behavioral intervention,the ethical issue in the consultation and detection for AIDS.This paper suggests that it should confront the current situation of AIDS prevention and control,improve the professional level of carrying out AIDS prevention and control,adhere to the necessary principles of AIDS prevention and control,and explore a new mode to construct AIDS prevention and control in colleges and universities.

Objective Decline in cognitive function caused by diabetes has become a research hotpots.The article aims to explore the relationship between serums regulated upon activation normal T cell expressed and secreted(RANTES) and cognitive dysfunction of newly diognosed T2DM patients, and provide a new way of prevention and treatment for newly diagnosed T2DM patients with cognitive dysfunction.Methods We retrospectively analyzed the general information and clinical biochemical indexes of the 123 patients who were first diagnosed of T2DM from March 2015 to September 2016 in Tangshan Worker''s Hospital.The levels of serum RANTES were measured by enzyme-linked immunosorbent assay (ELISA), and the cognitive function of all patients was assessed by Mini-mental State Examinatlon(MMSE)and Repeatable Battery for the Assessment of Neuropsyehologic Status(RBANS).Finally, newly diognosed T2DM patients were divided into T2DM non-cognitive disorder group and T2DM cognitive disorder group according to the MMSE score.We analyzed whether there are differences among general information,serum RANTES level and RBANS cognitive function score of two group patients.The correlations of RANTES with general information and cognitive scores were analyzed by single factor correlation and multiple stepwise regression analysis.Results ①The level of serum RANTESin T2DM cognitive disorder group[(2.62±0.37)mmol/L] was significantly higher compared to that in T2DM noncognitive disorder group[(2.29±0.36)mmol/L], and there was significant difference(P<0.001).②The instant memory,visual span,attention,delayed memory score and RBANS score of T2DM cognitive disorder group were(70.90±14.71)、(92.90±15.50)、(87.80±16.45)、(88.02±14.28)、(82.92±11.07), which were significant declined compared to those of T2DM non-cognitive disorder group [(85.28±13.97),(104.18±12.69),(101.51±12.94),(96.42±10.30),(95.84±9.94)], and there was significant difference (P≤0.05).There was no statistically significant difference between the two groups′ verbal function score [(96.08±7.87),(99.31±9.83)] (P=0.056).③The RANTES was negatively correlated with the total score of instant memory, visual span, verbal function, delayed memory score and RBANS score in T2DM patients(the valuue of r were-3.48、-2.35、-2.01、-3.02、-4.17).Conclusion There was a significant correlation between serum RANTES level and cognitive dysfunction, and elevated serum RANTES level could be used as an important indicator for monitoring newly diognosed T2DM patients with cognitive dysfunction.

Objective To explore the impact of authentic leadership on silence behavior of nurses and test the mediating effect of organizational support. Methods The 354 valid questionnaires were collected using the a cross-sectional survey with Authentic Leadership Questionnaire, Perceived Organizational Support Scale and Silence Behavior Scale between September to November in 2015, using the multiple line hierarchical regression analysis to test the relationship between variables. Results Authentic leadership could significantly promote the perceived organizational support of subordinate nurses (β= 0.543, P<0.01), which in turn, significantly restrain silence behavior of subordinate nurses (β=-0.323, P<0.01), the perceived organizational support completely mediate the relationship between authentic leadership and silence behavior (β=0.175, P<0.01). Conclusions By constructing the supporting work environment, authentic leadership can eliminates nurses′ voice worry, motivates the voice motivation and efficiency, in turn to break the silence. This article propose the action mechanisms from three perspectives.

Objective To establish a Chinese hamster model of babesia infection, to find the changing pattern of organs and biochemical parameters in Chinese hamster infected with Babesia, and to promote the detection and treatment of babesiosis.Methods Healthy 5-week old Chinese hamsters were infected by intraperitoneal injection of blood containing Babesia.Blood samples were collected at 0, 2, 4, 6, 8, 10, 12, 14, 16, 23, 30, and 37 days after infection from 5 hamsters at each time point.Blood smears were prepared to detect the parasites using Giemsa staining.ELISA assay was employed to test the IL-2 concentration.The blood biochemical indexes were detected using an automatic biochemical analyzer.DNA was extracted from the whole blood and REAL-TIME RCR was performed to determine the reproduction of Babesia.Aftert the animals were sacrificed, the heart, lung, spleen, liver, and kidney were taken to analyze the changes of organ coefficients.Results The highest level of Babesia in the hamsters occurred on day 4 after the Babesia injection, and then showing a decreasing tendency.However, there was a transient increase on the 12th day after infection.The liver and spleen displayed most extensive response to the infection showing hepatomegaly and splenomegaly, but the variation of heart and kidneys coefficients was within the norm.There were prominent changes of blood cells, especially leucocytes, with two peaks at day 10 and 23 after the Babesia infection.The peak changes of blood biochemical indexes occurred at day 12 after infection.The concentration of serum IL-2 reached a peak on the 10th day after infection.Conclusions The Chinese hamsters display typical characteristics of tick-borne diseases such as hepatomegaly and splenomegaly.The immunological system is activated along with the infection and reaches a highest stage in the second week.Afterwards the Babesia can live in the hamster body for a long period of time.The results of this study provide useful information supporting further studies on the detection, treatment and prevention of Babesiosis.