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Background: To identify patients at low risk of synchronous bone metastasis who should not receive bone scans when initially diagnosed with nasopharyngeal carcinoma (NPC). Methods: In total, 6652 patients were enrolled in the training cohort and 1919 patients in the multicenter external validation cohort. Logistic regression analyses were performed to assess independent predictors of synchronous bone metastasis for the nomogram model. Results: After risk stratification, 46.3% (3081/6652) patients were separated into the low‐risk group with an incidence of 0.71% for synchronous bone metastasis. The odds ratio of the intermediate and high‐risk groups was 5.61 and 23.82 times that of the low‐risk group, respectively. For patients with high EBV DNA, we recommend routine screening for N2‐3 female patients, but that all male subgroups are screened. Conclusions: Bone scans should not be routine. Patients in the low‐risk group should not be screened, which would avoid excessive radiation and economize iatrical resource. [ABSTRACT FROM AUTHOR]

Background: To develop a common follow‐up strategy for appropriate imaging examination at an appropriate time for nasopharyngeal carcinoma (NPC). Methods: Independent prognostic factors were identified by Cox regression analysis, and a nomogram model was developed. Random survival forest (RSF) model was constructed to depict probability of disease failure during a 5‐year follow‐up and establish a reasonable risk‐based follow‐up strategy. Results: The nomogram model finally categorized the patients into three risk groups. RSF model demonstrated distribution trends for local and regional recurrences, bone metastasis, liver metastasis, and lung metastasis of NPC. Adequate imaging at follow‐up should be considered between 10 and 21 months for patients at moderate‐risk of recurrence or metastasis and 7–36 months for those at high‐risk. Conclusions: The temporal distribution of incidence rates of recurrence or metastasis varied among different risk groups. We recommend implementing a focused and targeted imaging surveillance intervention at appropriate times to improve its efficiency and reduce costs. [ABSTRACT FROM AUTHOR]

The mechanism for general base catalyzed solvolysis of dimethylphenylphenoxysilane involves base-catalyzed removal of proton from the attacking solvent molecule with simultaneous formation of silicon-oxygen bond. The reaction is characteristics of a true general base catalysis and not of specific base general acid catalysis. The relationship between structure-reactivity and a positive cross-interaction coefficient confirm the true general base catalysis mechanism.

General acid catalysis, general base catalysis and bifunctional catalysis of the trifluoroethanolysis of dimethyphenylphenoxysilane occur by a similar mechanism. The transition state for general base catalysis is the same as that for bifunctional catalysis except for the assistance of the leaving group by a trifluoroethanol molecule. The trifluoroethanol molecule stabilizes the phenoxide oxygen negative charge by hydrogen bonding. In acid-catalyzed reaction, trifluoroethanol molecules assist one another by hydrogen bonding as the nucleophile oxygen-silicon bond is formed.

Freeze-thaw cycle damage is one of the main diseases of buildings in cold regions which seriously affects the normal performance of buildings and the safety of long-term use. Under the condition of freeze-thaw cycle for concrete bridge cracks different freeze-thaw cycles were set up and several different crack repair methods were provided to test the freeze-thaw cycle and mechanical properties of concrete blocks and study the crack reinforcement effect then the relationship between the number of freeze-thaw cycles and the crack repair method is obtained. The experimental results show that with the increase of freeze-thaw cycles the carbon fiber cloth and epoxy resin have good effect on repairing cracks the five repair methods have obvious advantages over the control group in terms of mechanical properties and show good resistance to freeze-thaw damage. [ABSTRACT FROM AUTHOR]

The analysis of gene function in mature and activated natural killer cells has been hampered by the lack of model systems for Cre-mediated recombination in these cells. Here we have investigated the utility of GzmbCre for recombination of loxp sequences in these cells predicated on the observation that Gzmb mRNA is highly expressed in mature and activated natural killer cells. Using two different reporter strains we determined that gene function could be investigated in mature natural killer cells after GzmbCre mediated recombination in vitro in conditions that lead to natural killer cell activation such as in the cytokine combination of interleukin 2 and interleukin 12. We demonstrated the utility of this model by creating GzmbCre;Rosa26IKKbca mice in which Cre-mediated recombination resulted in expression of constitutively active IKKβ, which results in activation of the NFκB transcription factor. In vivo and in vitro activation of IKKβ in natural killer cells revealed that constitutive activation of this pathway leads to natural killer cell hyper-activation and altered morphology. As a caveat to the use of GzmbCre we found that this transgene can lead to recombination in all hematopoietic cells the extent of which varies with the particular loxp flanked allele under investigation. We conclude that GzmbCre can be used under some conditions to investigate gene function in mature and activated natural killer cells. [ABSTRACT FROM AUTHOR]

Background: Thyroid cancer (TC), the most common endocrine malignant tumor, is increasingly causing a huge threat to our health nowadays., Methods: To explore the tumorigenesis mechanism of thyroid cancer, we identified that long intergenic non-coding RNA-00891 (LINC00891) was upregulated in TC using the Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and local databases. LINC00891 expression was correlated with histological type and lymph node metastasis (LNM). The high expression of LINC00891 could serve as a diagnostic marker for TC and its LNM. In vitro experiments demonstrated that LINC00891 knockdown could inhibit cell proliferation, migration, invasion and prompt apoptosis and G1 arrest of TC cells. We also investigated the related mechanisms of LINC00891 promoting TC progression using RNA sequencing, Gene Set Enrichment Analysis, and Western blotting., Results: Our experiments demonstrated that LINC00891 promoted TC progression via the EZH2-SMAD2/3 signaling axis. In addition, overexpression of EZH2 could reverse the suppressive epithelial-to-mesenchymal transition (EMT) caused by LINC00891 knockdown., Conclusion: In conclusion, the LINC00891/EZH2/SMAD2/3 regulatory axis participated in tumorigenesis and metastasis of thyroid cancer, which may provide a novel target for treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

China is the largest chili pepper producing country, and Hebei Province stands out as the forth with planting area at about 1500 km2 in China. Pepper (Capsicum annuum L.) is susceptible to Colletotrichum spp. infection during its growth, which seriously affects production yield and quality. In September 2020, widespread anthracnose was observed on pepper in Hebei (115.48° N, 38.77° E), China. Necrotic lesions on pepper fruits were suborbcular, sunken, with acervuli arranged in the middle of lesion (e-Xtra 1A). To perform fungal isolation, small tissue with 0.3 cm2 in size at the symptomatic tissue margin was surface disinfested with 75% ethanol for 10 s, and 0.1% HgCl2 for 40 s, then washed three times with sterile ddH2O. Fragments were placed on potato dextrose agar (PDA) amended with 100 mg·L-1 chloramphenicol and incubated at 28 ºC under darkness for 4 days. One of the strains of Colletotrichum spp., named HQY157, was purified by single-spore isolation, then used for morphological characterization, phylogenetic analysis, and pathogenicity tests. Colonies presented light grey aerial mycelium, occasionally mixed with gray-black strips, and the reverse was similar to the surface on PDA (e-Xtra 1B). Conidia were smooth-walled, aseptate, straight with obtuse to slightly rounded ends, 17.3-28.5 × 3.1-7.4 μm (n=50) (e-Xtra 1C). For molecular identification, the internal transcribed spacer (ITS) region, partial sequences of actin (ACT), β-tublin (TUB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and chitin synthase (CHS) were sequenced using the specific primers (Weir et al. 2012). Sequences were deposited in GenBank with the following accession numbers OM317600-OM317604. A Maximum-Likelihood phylogenetic tree was constructed, based on the concatenated sequences (ACT, CHS, GAPDH, TUB, and ITS) of HQY157 and other closely matching Colletotrichum species obtained from GenBank, by using MEGA-X. It showed that HQY157 was grouped with the C. sojae with bootstrap values of 100% (e-Xtra 2). To confirm the pathogenicity, surface-sterilized healthy pepper fruits and healthy fruits with wounds (deal with a sterile toothpick after surface-sterilized) were then inoculated with 2 μL of conidial suspension (106 conidia/mL). The fruits inoculated with 2 μL sterile distilled water were taken as negative controls. After inoculation, the fruits were kept in a plastic box with sterilized filter paper moistened with sterilized water, and maintained at 25°C in the dark. The experiment was repeated three times. Anthracnose symptoms were observed 7 days after inoculation on the wounded pepper fruits, whereas the unwounded and negative control fruits remained symptomless (e-Xtra 1D). Colletotrichum sojae was re-isolated from the infected pepper fruits and identified by morphological and molecular analysis, fulfilling Koch's postulates. Colletotrichum sojae occurs mainly on Fabaceae plants such as Glycine max, Medicago sativa, Phaseolus vulgaris, and Vigna unguiculata (Damm et al. 2019, Talhinhas and Baroncelli, 2021), and Panax quinquefolium (Guan et al. 2021). To our knowledge, this is the first report of C. sojae causing anthracnose on pepper in China. This study provided crucial information for epidemiologic studies and appropriate control strategies for this chili pepper disease.