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The waste from nuclear power plants worldwide has to be isolated from humans and his environment for about 100 000 years to equal the levels of natural uranium. If, however, the long-lived actinides could be separated from the spent fuel and transmuted, then the isolation time could be shortened to about 1 000 years. It is known that one class of N-containing soft ligands has excellent extraction ability and selectivity for minor actinides (MA), the separation of MA/lanthanides(Ln) from high level waste has been expected. One of the limiting points to ensure a safe and stable long-term operation is the resistance against radiation of all chemicals involved in the systems due to the highly radioactive field and high nitric acid concentration. Derivatives of 2,6-bis(1,2,4-triazine-3-yl)pyridine(BTP), 6,6'-bis(1,2,4-triazin-3-yl)-2,2'-bipyridine(R-BTBP) and 2,9-bis(1,2,4-triazin-3-yl)-1,10-phenanthroline(R-BTPhen) were widely employed for trivalent minor actinoid and lanthanoid separation in the promising innovative Selective Actinide Extraction(i-SANEX) and Grouped Actinide Extraction(EURO-GANEX) processes. However, researches towards radiolytic stability of these N-donor ligands presented controversial results. Herein, researches on stability against γ-radiation or α-radiation of R-BTP, R-BTBP, R-BTPhen and 2,6-bis[1H-1,2,3-triazol-4-yl]-pyridine(PyTri) at different experimental conditions and solvent formulations are reviewed. In most cases, γ irradiations were performed using 60Co sources and α irradiation were performed using 241Am or 244Cm solution. The effects of molecular structure, dose and dose rate, contact between phases, oxygen content, different phase composition, acidity, diluent and phase modifier on the γ-radiation stability of these ligands are introduced. The performance and changes in the composition have been analyzed during the irradiation experiment by different techniques, such as Raman spectroscopy, HPLC-MS and ICP-MS, to determine the degradation of the organic or aqueous solvents. These data were used to provide critical insight into the fundamental radiolysis mechanisms responsible for the radiolytic stability of ligands. In general, degradation was slower in the presence of both organic and aqueous phases during irradiation for both the hydrophobic and hydrophilic ligands. However, different experimental conditions and solvent formulations may lead to different degradation paths and degradation rates, and these experimental results are not comparable. Moreover, it is generally accepted that simulate radiation conditions, usually 60Co, may exaggerate or underestimate the influence of radiation effects. The controversial results obtained demonstrate the importance of developing realistic irradiation experiments where different factors affecting the performance can be easily studied and isolated. The existing problems in the study of radiolytic stability are summarized, and the key research directions in this field are prospected.

Spermatogenesis in mammals is characterized by two waves of piRNA expression: one corresponds to classic piRNAs responsible for silencing retrotransponsons and the second wave is predominantly derived from nontransposon intergenic regions in pachytene spermatocytes, but the function of these pachytene piRNAs is largely unknown. Here, we report the involvement of pachytene piRNAs in instructing massive mRNA elimination in mouse elongating spermatids (ES). We demonstrate that a piRNA-induced silencing complex (pi-RISC) containing murine PIWI (MIWI) and deadenylase CAF1 is selectively assembled in ES, which is responsible for inducing mRNA deadenylation and decay via a mechanism that resembles the action of miRNAs in somatic cells. Such a highly orchestrated program appears to take full advantage of the enormous repertoire of diversified targeting capacity of pachytene piRNAs derived from nontransposon intergenic regions. These findings suggest that pachytene piRNAs are responsible for inactivating vast cellular programs in preparation for sperm production from ES.

Purpose: To characterize the alterations of intestinal bacteria and immunological function in patients with oral squamous cell carcinoma(OSCC) before and after treatment., Methods: From September 2020 to September 2021, 28 patients suffering OSCC and 10 healthy volunteers undergoing treatment at our hospital were enrolled in the study. Conventional treatment regimens were administered to OSCC patients and the changes in immune function, intestinal bacteria composition and short-chain fatty acids were measured 1 week before and 6 months after therapy. GraphPad Prism 9.0 software package was used for data analysis., Results: Immunological function measurements indicated significantly lower levels of lymphocyte subsets (including CD3 + , CD4 + , NK, CD4 + /CD8 + ) and immunoglobulins (including IgG, IgA, IgM) in the peripheral blood of OSCC patients before treatment compared to healthy volunteers (P<0.05), as well as remarkably lower levels of serum cytokines (including TNF-α、IL-4、IL-6) (P<0.05). Following 6 months of conventional treatment, there was an improvement in immune function in OSCC patients compared to all patients before treatment(P<0.05). Compared to healthy volunteers, the diversity of intestinal bacteria was decreased in OSCC patients before treatment, whereas the diversity of intestinal bacteria recovered in OSCC patients after conventional treatment. At the phylum, the distribution of Epsilonbacteraeota, Proteobacteria and Patescibacteria were significantly elevated and the concentration of Verrucomicrobia was decreased in OSCC patients before treatment compared to healthy volunteers(P<0.05). Intriguingly, convention therapy reversed the disturbance of intestinal bacteria, including downgrading levels of Epsilonbacteraeota, Proteobacteria and Patescibacteria and increasing levels of Verrucomicrobia(P<0.05). Short-chain fatty acids (including acetic acid, propionic acid and butyric acid) were present at a lower level in the intestine of OSCC patients before treatment and were elevated after conventional treatment., Conclusions: Conventional treatment remarkably enhances immune function, revitalizes the distribution of intestinal microflora, elevates the content of short-chain fatty acids in the intestine of OSCC patients, thereby improving the patients' health.

Oleanolic acid (OA), a naturally occurring triterpenoid, exhibits potential antitumor activity in many tumor cell lines. Gallbladder carcinoma is the most common malignancy of the biliary tract, and is a highly aggressive tumor with an extremely poor prognosis. Unfortunately, the effects of OA on gallbladder carcinoma are unknown. In this study, we investigated the effects of OA on gallbladder cancer cells and the underlying mechanism. The results showed that OA inhibits proliferation of gallbladder cancer cells in a dose-dependent and time-dependent manner on MTT and colony formation assay. A flow cytometry assay revealed apoptosis and G0/G1 phase arrest in GBC-SD and NOZ cells. Western blot analysis and a mitochondrial membrane potential assay demonstrated that OA functions through the mitochondrial apoptosis pathway. Moreover, this drug inhibited tumor growth in nude mice carrying subcutaneous NOZ tumor xenografts. These data suggest that OA inhibits proliferation of gallbladder cancer cells by regulating apoptosis and the cell cycle process. Thus, OA may be a promising drug for adjuvant chemotherapy in gallbladder carcinoma.

Objective: To compare the urinary 1-hydroxypyrene (1-OHP) concentrations between coke oven workers and non-occupational exposed individuals and to investigate the possible impact factors., Methods: Spot end-of-shift urine samples were collected in 265 coke oven workers and spot morning urine samples in 226 non-occupational exposed individuals. External exposure levels and possible confounding factors were assessed by environmental polycyclic aromatic hydrocarbons (PAH) monitoring and uniform questionnaire, and the urinary 1-OHP concentrations determined by high performance liquid chromatography (HPLC), were used to compare the different urinary 1-OHP levels between different research populations and to explore the effects of several factors such as external exposure levels, smoking habits, alcohol consumptions, age and body mass index (BMI)., Results: The urinary 1-OHP concentrations in coke oven workers were significantly higher than those in non-occupational exposed individuals (13.49, 6.56, 1.38 and 0.35 micromol/mol creatinine for topside workers, side-oven workers, bottom side workers and references, respectively, P < 0.001; the same trends for the percentage of the level over 2.3 micromol/mol creatinine: 94.81%, 84.73%, 35.09% and 0.88%, P < 0.001). The control individuals who smoked over 20 cigarettes per day possessed higher urinary 1-OHP concentrations than the non-smokers (adjusted geometric mean: 0.47 and 0.31 micromol/mol creatinine, respectively, P < 0.05). Alcohol drinking references possessed lower urinary 1-OHP levels than the non-drinkers (adjusted geometric mean: 0.33 and 0.47 micromol/mol creatinine, respectively, P < 0.05)., Conclusion: Coke oven workers should be exposed to a high level of urinary 1-OHP, especially for topside workers and side-oven workers. Background urinary 1-OHP levels in non-occupational exposed individuals should be related to smoking habits and alcohol consumptions.

Objective: To study the characteristics of occupational exposure of polycyclic aromatic hydrocarbons (PAHs) in coke oven workers., Methods: Samples were collected individually and PAHs concentration in the ambient air were assayed by high performance liquid chromatography (HPLC) and toxic equivalency factors (TEFs) were introduced to assess the carcinogenic potency., Results: The levels of PAHs occupational exposure in oven workers at topside was higher than at side oven and bottom oven (P < 0.05). Non-carcinogenic PAHs were more than 70% of total PAHs and benzo[a]pyrene accounted for 65.5% approximately 72.4% of total benzo[a]pyrene equivalents. Total occupational exposure level of PAHs in coke oven workers was positively related to the content of benzo[a]pyrene and pyrene, respectively (r(2) = 0.84, r(2) = 0.94, P < 0.05)., Conclusion: Coke oven workers were exposed to a high level of PAHs which possessed some extent of carcinogenic potency, and benzo[a]pyrene is the chief carcinogenic substance.