Long-term follow-up and prognostic analysis of parotid tumors in children and adolescents.

Objectives: The objective of this study is to summarize the clinical characteristics, treatment, and prognosis of parotid tumors in children and adolescents. Methods: Fifty-three children and adolescents diagnosed with parotid gland tumors were included. Survival was evaluated using the Kaplan-Meier method. Log-rank test and multivariate analysis were used to analyze the association between clinical factors and recurrence. Results: Of the 53 patients, 30 cases were benign and 23 cases were malignant. All patients underwent surgery. Patients with malignant tumors with high-risk factors received radiotherapy or chemotherapy. The median follow-up time was 61 months. Of these, 1 patient with benign tumor and 5 patients with malignant tumors recurred. Of the patients with malignant tumors, 2 developed distant metastases and 2 died. The 5-year overall survival (OS) and 5-year locoregional recurrence-free survival (LRFS) rates for benign tumors were 100.0% and 92.9%, respectively, whereas the 5-year OS and 5-year LRFS rates for malignant tumors were 94.4% and 72.5%, respectively. The log-rank univariate test showed that tumor size >3.5 cm (p = .056), distant metastasis (p = .056), and stage III and IV (p = .032) were associated with recurrence. However, multivariate analysis did not show the above factors to be independent prognostic factors for LRFS. Conclusion: Surgery for benign tumors depends on the location and size. Surgery for malignant parotid tumors depends mainly on the stage, grade, pathological type, and recurrence. Prophylactic lymph node dissection is required for high-grade tumors. Radiotherapy or chemotherapy for children needs more research. Both benign and malignant tumors have high survival rates after active treatment. Level of evidence: Level 2.

An analysis of health-related quality of life in children and adolescents after parotidectomy based on patient-reported outcomes.

PURPOSE: To assess health-related quality of life (HRQoL) and its influencing factors in these pediatric patients undergoing parotidectomy. METHODS: This was a cross-sectional study that included 37 children and adolescents (≤ 19 years) with parotid gland tumors who were treated in Sichuan Cancer Hospital between January 2006 and November 2021. HRQoL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30). The Wilcoxon rank sum test was used to analyze the factors influencing patients' HRQoL. RESULTS: 37 children and adolescents were included in the study, including 22 cases of benign tumors and 15 cases of malignant tumors. All patients underwent surgery, and some patients with malignant tumors received radiotherapy or chemotherapy. Malignancy, permanent facial palsy, and Frey syndrome were associated with worse HRQoL in children and adolescents with parotid gland tumors. Radiotherapy and no cervical lymph node dissection were associated with worse HRQoL in pediatric patients with malignancy. The surgical approach of parotid is not a factor influencing HRQoL. CONCLUSION: Factors associated with HRQoL in children and adolescents with parotid gland tumors include pathological types, permanent facial palsy, and Frey syndrome. In addition, factors affecting patients with malignancy include lateral lymph node dissection and radiotherapy.

Psychometric properties of the Career Adapt-Abilities Scale-Short Form: evidence from Chinese elite athletes.

Objectives: The present study aimed to examine the psychometric properties of the Chinese version of the Career Adapt-Abilities Scale-Short Form (CAAS-SF) among a sample of Chinese elite athletes. Methods: A sample of Chinese elite athletes (n = 770) was invited to participate in this study. First, the factor structure of the Chinese version of the CAAS-SF was examined, and six measurement models (CFA, H-CFA, B-CFA, ESEM, H-ESEM, and B-ESEM) were constructed and compared. Second, the internal consistency reliability of the Chinese version of the CAAS-SF was examined. Finally, structural equation modeling (SEM) was employed to assess the nomological validity of the Chinese version of the CAAS-SF. Results: The results showed that the hierarchical ESEM (H-ESEM) model best represented the factor structure of the CAAS-SF among Chinese elite athletes. It suggests that the higher-order factor of career adaptability explains the four distinctive but interrelated specific factors of concern, control, curiosity, and confidence. Cronbach's alpha coefficients (0.84-0.90), composite reliability (0.81-0.96), and coefficient omega hierarchical (0.855-0.94) of the Chinese version of the CAAS-SF were larger than the cutoff values, which suggest satisfactory reliability. The results of the SEM revealed that the higher-order factor of career adaptability was positively associated with career decision self-efficacy (ß = 0.676, p < 0.001). This result is consistent with previous findings (r = 0.65, p < 0.01) and provided support for the nomological validity of the CAAS-SF among Chinese elite athletes. Conclusion: The findings of the present study indicated that the Chinese version of the CAAS-SF displayed satisfactory reliability and validity and could be used to assess the career adaptability of Chinese elite athletes. In addition, the total score of the CAAS-SF is suggested to be used in future research and practical works.

Targeting DNA polymerase ß elicits synthetic lethality with mismatch repair deficiency in acute lymphoblastic leukemia.

Mismatch repair (MMR) deficiency has been linked to thiopurine resistance and hypermutation in relapsed acute lymphoblastic leukemia (ALL). However, the repair mechanism of thiopurine-induced DNA damage in the absence of MMR remains unclear. Here, we provide evidence that DNA polymerase ß (POLB) of base excision repair (BER) pathway plays a critical role in the survival and thiopurine resistance of MMR-deficient ALL cells. In these aggressive resistant ALL cells, POLB depletion and its inhibitor oleanolic acid (OA) treatment result in synthetic lethality with MMR deficiency through increased cellular apurinic/apyrimidinic (AP) sites, DNA strand breaks and apoptosis. POLB depletion increases thiopurine sensitivities of resistant cells, and OA synergizes with thiopurine to kill these cells in ALL cell lines, patient-derived xenograft (PDX) cells and xenograft mouse models. Our findings suggest BER and POLB's roles in the process of repairing thiopurine-induced DNA damage in MMR-deficient ALL cells, and implicate their potentials as therapeutic targets against aggressive ALL progression.

Genome-wide mapping of protein-DNA damage interaction by PADD-seq.

Protein-DNA damage interactions are critical for understanding the mechanism of DNA repair and damage response. However, due to the relatively random distributions of UV-induced damage and other DNA bulky adducts, it is challenging to measure the interactions between proteins and these lesions across the genome. To address this issue, we developed a new method named Protein-Associated DNA Damage Sequencing (PADD-seq) that uses Damage-seq to detect damage distribution in chromatin immunoprecipitation-enriched DNA fragments. It is possible to delineate genome-wide protein-DNA damage interactions at base resolution with this strategy. Using PADD-seq, we observed that RNA polymerase II (Pol II) was blocked by UV-induced damage on template strands, and the interaction declined within 2 h in transcription-coupled repair-proficient cells. On the other hand, Pol II was clearly restrained at damage sites in the absence of the transcription-repair coupling factor CSB during the same time course. Furthermore, we used PADD-seq to examine local changes in H3 acetylation at lysine 9 (H3K9ac) around cisplatin-induced damage, demonstrating the method's broad utility. In conclusion, this new method provides a powerful tool for monitoring the dynamics of protein-DNA damage interaction at the genomic level, and it encourages comprehensive research into DNA repair and damage response.

Effects of replication domains on genome-wide UV-induced DNA damage and repair.

Nucleotide excision repair is the primary repair mechanism that removes UV-induced DNA lesions in placentals. Unrepaired UV-induced lesions could result in mutations during DNA replication. Although the mutagenesis of pyrimidine dimers is reasonably well understood, the direct effects of replication fork progression on nucleotide excision repair are yet to be clarified. Here, we applied Damage-seq and XR-seq techniques and generated replication maps in synchronized UV-treated HeLa cells. The results suggest that ongoing replication stimulates local repair in both early and late replication domains. Additionally, it was revealed that lesions on lagging strand templates are repaired slower in late replication domains, which is probably due to the imbalanced sequence context. Asymmetric relative repair is in line with the strand bias of melanoma mutations, suggesting a role of exogenous damage, repair, and replication in mutational strand asymmetry.

Nucleotide excision repair: a versatile and smart toolkit.

Nucleotide excision repair (NER) is a major pathway to deal with bulky adducts induced by various environmental toxins in all cellular organisms. The two sub-pathways of NER, global genome repair (GGR) and transcription-coupled repair (TCR), differ in the damage recognition modes. In this review, we describe the molecular mechanism of NER in mammalian cells, especially the details of damage recognition steps in both sub-pathways. We also introduce new sequencing methods for genome-wide mapping of NER, as well as recent advances about NER in chromatin by these methods. Finally, the roles of NER factors in repairing oxidative damages and resolving R-loops are discussed.

Psychometric Properties of the Chinese Translated Athlete Burnout Questionnaire: Evidence From Chinese Collegiate Athletes and Elite Athletes.

The purpose of the study was to translate the athlete burnout questionnaire (ABQ) into Simplified Chinese and examine its psychometric properties in Chinese collegiate athletes and elite athletes. Firstly, the factor structure, internal consistency reliability and nomological validity of the Chinese translated ABQ was examined in a sample of Chinese collegiate athletes (n = 214, 58.9% females). Secondly, abovementioned psychometric properties were examined in a sample of Chinese elite athletes (n = 505, 52.7% females). Finally, measurement invariance of the Chinese translated ABQ was examined across the two samples. It was found that the 12-item three-correlated-factors model outperformed the one factor model and bi-factor model in collegiate athlete sample whereas the 12-item bi-factor model best represented the factor structure of the Chinese translated ABQ in elite athlete sample. Satisfactory internal consistency reliabilities of the Chinese translated ABQ were evidenced in the two samples. Nomological validity was also supported by the results of the two samples that the three subscales of the ABQ were significantly associated with its theoretically related variables. Results of multiple-group confirmatory factor analysis revealed that weak measurement invariance of the Chinese translated ABQ (three-correlated-factors model) was evidenced across the two samples. Collectively, results of this study indicated that the 12-item Chinese translated ABQ could be used for measuring burnout of Chinese collegiate and elite athletes. Significance and implication of the current study as well as recommendations for future study were discussed.

A new technique for genome-wide mapping of nucleotide excision repair without immunopurification of damaged DNA.

Nucleotide excision repair functions to protect genome integrity, and ongoing studies using excision repair sequencing (XR-seq) have contributed to our understanding of how cells prioritize repair across the genome. In this method, the products of excision repair bearing damaged DNA are captured, sequenced, and then mapped genome-wide at single-nucleotide resolution. However, reagent requirements and complex procedures have limited widespread usage of this technique. In addition to the expense of these reagents, it has been hypothesized that the immunoprecipitation step using antibodies directed against damaged DNA may introduce bias in different sequence contexts. Here, we describe a newly developed adaptation called dA-tailing and adaptor ligation (ATL)-XR-seq, a relatively simple XR-seq method that avoids the use of immunoprecipitation targeting damaged DNA. ATL-XR-seq captures repair products by 3'-dA-tailing and 5'-adapter ligation instead of the original 5'- and 3'-dual adapter ligation. This new approach avoids adapter dimer formation during subsequent PCR, omits inefficient and time-consuming purification steps, and is very sensitive. In addition, poly(dA) tail length heterogeneity can serve as a molecular identifier, allowing more repair hotspots to be mapped. Importantly, a comparison of both repair mapping methods showed that no major bias is introduced by the anti-UV damage antibodies used in the original XR-seq procedure. Finally, we also coupled the described dA-tailing approach with quantitative PCR in a new method to quantify repair products. These new methods provide powerful and user-friendly tools to qualitatively and quantitatively measure excision repair.

UdgX-Mediated Uracil Sequencing at Single-Nucleotide Resolution.

As an aberrant base in DNA, uracil is generated by either deoxyuridine (dU) misincorporation or cytosine deamination, and involved in multiple physiological and pathological processes. Genome-wide profiles of uracil are important for study of these processes. Current methods for whole-genome mapping of uracil all rely on uracil-DNA N-glycosylase (UNG) and are limited in resolution, specificity, and/or sensitivity. Here, we developed a UdgX cross-linking and polymerase stalling sequencing ("Ucaps-seq") method to detect dU at single-nucleotide resolution. First, the specificity of Ucaps-seq was confirmed on synthetic DNA. Then the effectiveness of the approach was verified on two genomes from different sources. Ucaps-seq not only identified the enrichment of dU at dT sites in pemetrexed-treated cancer cells with globally elevated uracil but also detected dU at dC sites within the "WRC" motif in activated B cells which have increased dU in specific regions. Finally, Ucaps-seq was utilized to detect dU introduced by the cytosine base editor (nCas9-APOBEC) and identified a novel off-target site in cellular context. In conclusion, Ucaps-seq is a powerful tool with many potential applications, especially in evaluation of base editing fidelity.

Genome-wide analysis of 8-oxo-7,8-dihydro-2'-deoxyguanosine at single-nucleotide resolution unveils reduced occurrence of oxidative damage at G-quadruplex sites.

8-Oxo-7,8-dihydro-2'-deoxyguanosine (OG), one of the most common oxidative DNA damages, causes genome instability and is associated with cancer, neurological diseases and aging. In addition, OG and its repair intermediates can regulate gene transcription, and thus play a role in sensing cellular oxidative stress. However, the lack of methods to precisely map OG has hindered the study of its biological roles. Here, we developed a single-nucleotide resolution OG-sequencing method, named CLAPS-seq (Chemical Labeling And Polymerase Stalling Sequencing), to measure the genome-wide distribution of both exogenous and endogenous OGs with high specificity. Our data identified decreased OG occurrence at G-quadruplexes (G4s), in association with underrepresentation of OGs in promoters which have high GC content. Furthermore, we discovered that potential quadruplex sequences (PQSs) were hotspots of OGs, implying a role of non-G4-PQSs in OG-mediated oxidative stress response.

Single-nucleotide resolution analysis of nucleotide excision repair of ribosomal DNA in humans and mice.

The unique nucleolar environment, the repetitive nature of ribosomal DNA (rDNA), and especially the possible involvement of RNA polymerase I (RNAPI) in transcription-coupled repair (TCR) have made the study of repair of rDNA both interesting and challenging. TCR, the transcription-dependent, preferential excision repair of the template strand compared with the nontranscribed (coding) strand has been clearly demonstrated in genes transcribed by RNAPII. Whether TCR occurs in rDNA is unresolved. In the present work, we have applied analytical methods to map repair events in rDNA using data generated by the newly developed XR-seq procedure, which measures excision repair genome-wide with single-nucleotide resolution. We find that in human and mouse cell lines, rDNA is not subject to TCR of damage caused by UV or by cisplatin.

Genome-wide mapping of nucleotide excision repair with XR-seq.

Nucleotide excision repair is a versatile mechanism to repair a variety of bulky DNA adducts. We developed excision repair sequencing (XR-seq) to study nucleotide excision repair of DNA adducts in humans, mice, Arabidopsis thaliana, yeast and Escherichia coli. In this protocol, the excised oligomers, generated in the nucleotide excision repair reaction, are isolated by cell lysis and fractionation, followed by immunoprecipitation with damage- or repair factor-specific antibodies from the non-chromatin fraction. The single-stranded excised oligomers are ligated to adapters and re-immunoprecipitated with damage-specific antibodies. The DNA damage in the excised oligomers is then reversed by enzymatic or chemical reactions before being converted into a sequencing library by PCR amplification. Alternatively, the excised oligomers containing DNA damage, especially those containing irreversible DNA damage such as benzo[a]pyrene-induced DNA adducts, can be converted to a double-stranded DNA (dsDNA) form by using appropriate translesion DNA synthesis (TLS) polymerases and then can be amplified by PCR. The current genome-wide approaches for studying repair measure the loss of damage signal with time, which limits their resolution. By contrast, an advantage of XR-seq is that the repair signal is directly detected above a background of zero. An XR-seq library using the protocol described here can be obtained in 7-9 d.

Preparation and activity of glycosylated acetylsalicylic acid.

The glycosylated acetylsalicylic acid was prepared with bromo-α-d-galactose and acetylsalicylic acid. It indicated that the glycosylated acetylsalicylic acid had lower cytotoxicity than underivatized acetylsalicylic acid, and might selectively display anticancer activity in this situation that had enzyme or no enzyme.

Anomalous Capillary Rise under Nanoconfinement: A View of Molecular Kinetic Theory.

Understanding the capillary filling behaviors in nanopores is crucial for many science and engineering problems. Compared with the classical Bell-Cameron-Lucas-Washburn (BCLW) theory, anomalous coefficient is always observed because of the increasing role of surfaces. Here, a molecular kinetics approach is adopted to explain the mechanism of anomalous behaviors at the molecular level; a unified model taking account of the confined liquid properties (viscosity and density) and slip boundary condition is proposed to demonstrate the macroscopic consequences, and the model results are successfully validated against the published literature. The results show that (1) the effective viscosity induced by the interaction from the pore wall, as a function of wettability and the pore dimension (nanoslit height or nanotube diameter), may remarkably slow down the capillary filling process more than theoretically predicted. (2) The true slip, where water molecules directly slide on the walls, strongly depends on the wettability and will increase as the contact angle increases. In the hydrophilic nanopores, though, the magnitude may be comparable with the pore dimensions and promote the capillary filling compared with the classical BCLW model. (3) Compared with the other model, the proposed model can successfully predict the capillary filling for both faster or slower capillary filling process; meanwhile, it can capture the underlying physics behind these behaviors at the molecular level based on the effective viscosity and slippage. (4) The surface effects have different influence on the capillary filling in nanoslits and nanotubes, and the relative magnitude will change with the variation of wettability as well as the pore dimension.

Cisplatin-DNA adduct repair of transcribed genes is controlled by two circadian programs in mouse tissues.

Cisplatin is a major cancer chemotherapeutic drug. It kills cancer cells by damaging their DNA, mainly in the form of Pt-d(GpG) diadducts. However, it also has serious side effects, including nephrotoxicity and hepatotoxicity that limit its usefulness. Chronotherapy is taking circadian time into account during therapy to improve the therapeutic index, by improving efficacy and/or limiting toxicity. To this end, we tested the impact of clock time on excision repair of cisplatin-induced DNA damage at single-nucleotide resolution across the genome in mouse kidney and liver. We found that genome repair is controlled by two circadian programs. Repair of the transcribed strand (TS) of active, circadian-controlled genes is dictated by each gene's phase of transcription, which falls across the circadian cycle with prominent peaks at dawn and dusk. In contrast, repair of the nontranscribed strand (NTS) of all genes, repair of intergenic DNA, and global repair overall peaks at Zeitgeber time ZT08, as basal repair capacity, which is controlled by the circadian clock, peaks at this circadian time. Consequently, the TS and NTS of many genes are repaired out of phase. As most cancers are thought to have defective circadian rhythms, these results suggest that future research on timed dosage of cisplatin could potentially reduce damage to healthy tissue and improve its therapeutic index.

Extraction, characterisation and antioxidant activity of polysaccharides from Chinese watermelon.

Extraction and antioxidant activity of polysaccharides from the Chinese watermelon was investigated. The polysaccharides were obtained by hot water extraction, ethanol precipitation, and deproteinization with HCl, respectively. The molecular weight was 3.02 × 104. It showed by high performance liquid chromatography (HPLC) and TLC that Chinese watermelon polysaccharides consisted of six monosaccharides, namely glucose, galactose, mannose, xylose, arabinose, and rhamnose. The polysaccharides contained the ß-glycosidic bond. Moreover, it was proved that the polysaccharides had high scavenging ability to superoxide anions.

RNA polymerase II is released from the DNA template during transcription-coupled repair in mammalian cells.

In mammalian cells, bulky DNA adducts located in the template but not the coding strand of genes block elongation by RNA polymerase II (RNAPII). The blocked RNAPII targets these transcription-blocking adducts to undergo more rapid excision repair than adducts located elsewhere in the genome. In excision repair, coupled incisions are made in the damaged DNA strand on both sides of the adduct. The fate of RNAPII in the course of this transcription-coupled repair (TCR) pathway is unclear. To address the fate of RNAPII, we used methods that control transcription to initiate a discrete "wave" of elongation complexes. Analyzing genome-wide transcription and repair by next-generation sequencing, we identified locations of elongation complexes and transcription-repair coupling events in genes throughout the genome. Using UV-exposed human skin fibroblasts, we found that, at the dose used, a single wave of elongation complexes was blocked within the first 25 kb of genes. TCR occurred where the elongation complexes were blocked, and repair was associated with the dissociation of these complexes. These results indicate that individual elongation complexes do not engage in multiple rounds of TCR with successive lesions. Our results are consistent with a model in which RNAPII is dissociated after the dual incision of the transcription-blocking lesion, perhaps by Cockayne syndrome group B translocase, or during the synthesis of a repair patch.

Preparation, deproteinization, characterisation, and antioxidant activity of polysaccharide from cucumber (Cucumis saticus L.).

Preparation, deproteinization and antioxidant activity of polysaccharide from cucumber (Cucumis saticus L.) were investigated. The crude cucumber polysaccharide was extracted by hydrothermal method. It showed that the trichloroacetic acid (TCA) method had the higher deproteinization percentage, but a little higher polysaccharide loss percentage than the CaCl2 method. The cucumber polysaccharide is linked by the ß-glycosidic linkage. It consisted of d-glucose, d-mannose, d-galactose, l-rhamnose, d-xylose, l-arabinose, d-glucuronic acid, and d-galacturonic acid. Their mole ratio was 6.00:4.03:8.31:2.82:2.75:6.60:1.05:5.79. Moreover, it proved that the cucumber polysaccharide had high scavenging ability to superoxide anions.

Molecular mechanisms and genomic maps of DNA excision repair in Escherichia coli and humans.

Nucleotide excision repair is a major DNA repair mechanism in all cellular organisms. In this repair system, the DNA damage is removed by concerted dual incisions bracketing the damage and at a precise distance from the damage. Here, we review the basic mechanisms of excision repair in Escherichia coli and humans and the recent genome-wide mapping of DNA damage and repair in these organisms at single-nucleotide resolution.