A one-step process to introduce both the aromatic and aliphatic primary amino groups with high chemoselectivity was developed. Triplet state acetone abstracts the hydrogen atoms from both the C--H ...bond of the polymeric film substrate and the O--H bond of phenol which is the building block and the amino group carrier. As a result, two kinds of free radicals, confined carbon-centered chain radicals of the polymer substrate and mobile oxygen-centered phenoxy radicals, were generated. Then the C--O bonds were formed by the coupling reaction between these two kinds of free radicals, p-Tyrarnine and p-aminophenol were used as amino carriers. The successful introduction of amino groups onto LDPE, BOPP and PET film substrates was demonstrated by measurements of water contract angle （CA）, ultraviolet spectra （UV）, X-ray photoelectron spectroscopy （XPS） and fluorescent microscopy. The processing factors, such as the UV-light intensity and irradiation time, concentrations of p-tyramine and p-aminophenol, and the ratio of acetone/water were investigated. The optimized process parameters are as follows： UV light intensity 9500 ~tW/cm2; irradiation time 18 min for BOPP and LDPE, 22 min for PET; the ratio of acetone/water = 1; and concentration ofp-tyramine and p-aminophenol 15% for BOPP and LDPE, 1% for PET. Based on the UV absorbance, the amino groups on the polymeric substrates were estimated to be in the range of 6.3 × 10-6-9.5 × 10-6 mmol/mm2.
Budding yeast Cdc13-Stnl-Tenl （CST） complex plays an essential role in telomere protection and maintenance, and has been proposed to be a telomere-specific replication protein A （RPA）-like complex. ...Previous genetic and structural studies revealed a close resemblance between Stnl-Tenl and RPA32-RPA14. However, the relationship between Cdc13 and RPA70, the largest subunit of RPA, has remained unclear. Here, we report the crystal structure of the N-terminal OB （oligonucleotide/oligosaccharide binding） fold of Cdc13. Although Cdc13 has an RPA70-1ike domain organization, the structures of Cdc130B folds are significantly different from their counterparts in RPA70, suggesting that they have distinct evolutionary origins. Furthermore, our structural and biochemical analyses revealed unexpected dimerization by the N-terminal OB fold and showed that homodimerization is probably a conserved feature of all Cdc13 proteins. We also uncovered the structural basis of the interaction between the Cdc13 N-terminal OB fold and the catalytic subunit of DNA polymerase a （Poll）, and demonstrated a role for Cdc13 dimerization in Poll binding. Analysis of the phenotypes of mutants defective in Cdc13 dimerization and Cdc13-Poll interaction revealed multiple mechanisms by which dimerization regulates telomere lengths in vivo. Collectively, our findings provide novel insights into the mechanisms and evolution of Cdc13.
BACKGROUNDSialolithiasis is one of the most common salivary gland disorders, most commonly affecting the submandibular gland. Submandibular sialolithiasis can be treated using non-invasive ...conservative measures and invasive treatments. Treatment selection was based on the ductal system anatomy and the size and location of the stones. This study aimed to review the updates on sialolithiasis treatment and compare the different management strategies of the variables. CASE SUMMARYThis report presents a case of a long-term, rare, and giant sialolithiasis within the submandibular gland parenchyma for 30 years in an older adult. Our patient presented with painless right submandibular swelling. Computed tomography revealed a calcified mass measuring 35 mm × 20 mm within the right submandibular gland. In this case, the infection and fibrosis of the affected gland and size of the stone did not provide us with other alternatives except for the excision of the involved gland. Thus, right submandibular sialoadenectomy was performed via the transcervical approach. After the surgery, the patient recovered without any complaints, side effects, or complications. CONCLUSIONTailored management is important for preserving gland function, maintaining low risk, and reducing patient discomfort.
Age, gender, and perinatal infection are associated with hepatocarcinogenesis. The influence of perinatal transmission in chronic hepatitis B virus infection between genders at different ages is not ...well documented.
A consecutive series of individuals who had general check-ups and three groups of relatives of patients with hepatocellular carcinoma were analyzed. Siblings of index cases and children of female index cases represented groups with high perinatal transmission, while children of male index cases represented a low perinatal transmission group.
A total of 45,035 individuals who had general check-ups and 14,513 first degree relatives of patients with hepatocellular carcinoma were included. The families of patients with hepatocellular carcinoma included 4,455 siblings of index cases, 7,111 children of male index cases, and 2,947 children of female index cases. The prevalence of hepatitis B surface antigen (HBsAg) was high in groups with high perinatal infection and in men. Gender differences in the prevalence of HBsAg diminished in children of female index cases and siblings of index cases, and in all groups after the age of 60 years. The prevalence of HBsAg declined with increasing age in all groups, with the highest decline in male siblings of index cases ( 1.37% per year) and the lowest in female children of male index cases ( 0.05% per year) in the 35-59 year-old period. Hepatitis C antibody was higher in women (5.7%) than in men (4.0%) in the general check-up group.
Females were less susceptible to become HBsAg carriers if HBV was not transmitted during the perinatal period. The prevalence of HBsAg declined significantly in high perinatal infection groups, implying that neonatal tolerance does not endure.
The example of the preparation ofnano- and micro-scaled, coral-shaped and core-shell topological morphology of copolyethylene particles promoted by the novel heterogeneous non-metallocene catalyst ...（m-CH3PhO）TiC13/carbon nanotubes （CNTs） was reported. Mass fraction of titanium component of the catalyst was 4.0 wt% determined by ICP analysis. The catalyst system can effectively catalyze polymerization of ethylene and eopolymerization of ethylene with 1-hexene. Morphological examination of the obtained polymer particles was carried out by scanning electron microscope （SEM） and high resolution transmission electron microscope （HR-TEM） technique. The results revealed that the morphology of the nascent copolyethylene particles looked like coral shape with size in micro-scaled and featured the core-shell structure consisting of CNTs as the core and copolyethylene as the shell.
The selective cationic polymerization of isobutylene （IB） initiated by a BF3-cyclohexanol （CL） complex was carried out from the mixed Ca fraction feed containing the 4C saturated and unsaturated ...hydrocarbons at -20℃. The effects of CL concentration, BF3 concentration, solvent for preparing BF3·CL complex and polymerization time on the chemical structure of end groups, number-average molecular weight （Mn） and molecular weight distribution （MWD, Mw/Mn） of the resulting polymers were investigated. The experimental results indicate that the BF3·CL complex initiating system exhibited an extremely high selectivity toward the cationic polymerization of IB in the mixed C4 fraction feed and low molecular weight （Mn = 900-3600） polyisobutylenes （PIBs） with large proportion of exo-double bond end groups were obtained. The exo-double bond content in PIB chain ends increased by increasing CL concentration or by decreasing solvent polarity in initiating system, BF3 concentration and polymerization time. The M, and MWD of the resulting PIBs were dependent on the concentrations of CL and BF3. Highly reactive PIBs with around 90 mol% of exo-double bonds were successfully synthesized by the selective polymerization of IB from the mixed Ca fraction feed, providing a potentially practical process for its simplicity and low costs.
γδ T cells are a distinct subgroup of T cells that bridge the innate and adaptive immune system and can attack cancer cells in an MHC-unrestricted manner. Trials of adoptive γδ T cell transfer in ...solid tumors have had limited success. Here, we show that DNA methyltransferase inhibitors (DNMTis) upregulate surface molecules on cancer cells related to γδ T cell activation using quantitative surface proteomics. DNMTi treatment of human lung cancer potentiates tumor lysis by ex vivo-expanded Vδ1-enriched γδ T cells. Mechanistically, DNMTi enhances immune synapse formation and mediates cytoskeletal reorganization via coordinated alterations of DNA methylation and chromatin accessibility. Genetic depletion of adhesion molecules or pharmacological inhibition of actin polymerization abolishes the potentiating effect of DNMTi. Clinically, the DNMTi-associated cytoskeleton signature stratifies lung cancer patients prognostically. These results support a combinatorial strategy of DNMTis and γδ T cell-based immunotherapy in lung cancer management.
The treatment of hepatocellular carcinoma (HCC) is particularly challenging due to the inherent tumoral heterogeneity and easy resistance towards chemotherapy and immunotherapy. Arsenic trioxide ...(ATO) has emerged as a cytotoxic agent effective for treating solid tumors, including advanced HCC. However, its effectiveness in HCC treatment remains limited, and the underlying mechanisms are still uncertain. Therefore, this study aimed to characterize the effects and mechanisms of ATO in HCC. By evaluating the susceptibilities of human and murine HCC cell lines to ATO treatment, we discovered that HCC cells exhibited a range of sensitivity to ATO treatment, highlighting their inherent heterogeneity. A gene signature comprising 265 genes was identified to distinguish ATO-sensitive from ATO-insensitive cells. According to this signature, HCC patients have also been classified and exhibited differential features of ATO response. Our results showed that ATO treatment induced reactive oxygen species (ROS) accumulation and the activation of multiple cell death modalities, including necroptosis and ferroptosis, in ATO-sensitive HCC cells. Meanwhile, elevated tumoral immunogenicity was also observed in ATO-sensitive HCC cells. Similar effects were not observed in ATO-insensitive cells. We reported that ATO treatment induced mitochondrial injury and mtDNA release into the cytoplasm in ATO-sensitive HCC tumors. This subsequently activated the cGAS-STING-IFN axis, facilitating CD8
T cell infiltration and activation. However, we found that the IFN pathway also induced tumoral PD-L1 expression, potentially antagonizing ATO-mediated immune attack. Additional anti-PD1 therapy promoted the anti-tumor response of ATO in ATO-sensitive HCC tumors. In summary, our data indicate that heterogeneous ATO responses exist in HCC tumors, and ATO treatment significantly induces immunogenic cell death (ICD) and activates the tumor-derived mtDNA-STING-IFN axis. These findings may offer a new perspective on the clinical treatment of HCC and warrant further study.
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