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Radiation-induced gastrointestinal (GI) tract toxicity halts radiotherapy and degrades the prognosis of cancer patients. Physical activity defined as “any bodily movement produced by skeletal muscle that requires energy expenditure” is a beneficial lifestyle modification for health. Here, we investigate whether walking, a low-intensity form of exercise, could alleviate intestinal radiation injury. Short-term (15 days) walking protected against radiation-induced GI tract toxicity in both male and female mice, as judged by longer colons, denser intestinal villi, more goblet cells, and lower expression of inflammation-related genes in the small intestines. High-throughput sequencing and untargeted metabolomics analysis showed that walking restructured the gut microbiota configuration, such as elevated Akkermansia muciniphila, and reprogramed the gut metabolome of irradiated mice. Deletion of gut flora erased the radioprotection of walking, and the abdomen local irradiated recipients who received fecal microbiome from donors with walking treatment exhibited milder intestinal toxicity. Oral gavage of A. muciniphila mitigated the radiation-induced GI tract injury. Importantly, walking did not change the tumor growth after radiotherapy. Together, our findings provide novel insights into walking and underpin that walking is a safe and effective form to protect against GI syndrome of patients with radiotherapy without financial burden in a preclinical setting.

Huoxiang (Agastache rugosa, family Labiatae) is used as a traditional Chinese medicine. In 2017, Huoxiang with stunted, chlorotic, and mosaic symptoms were found in Haidian District of Beijing, China. To identify the causal agent(s), total RNA of symptomatic leaves was extracted and further analyzed by high-throughput sequencing (HTS). Sequence analyses revealed nine contigs with high nucleotide sequence identity (93%–100%) with tomato yellow leaf curl virus (TYLCV) from the genus Begomovirus, family Geminiviridae and seventeen contigs with high nucleotide sequence identity (85%–100%) with cucumber mosaic virus (CMV) from the genus Cucumovirus, family Bromoviridae. To confirm the HTS results, RT-PCR was performed with TYLCV-specific primers and CMV-specific primers, respectively. Two fragments of 651 bp (GenBank accession No. MG775386) and 657 bp (MG754206) were obtained, respectively. Sequencing and BLASTn analysis revealed that the 651 bp fragment shared 100% nucleotide identity with TYLCV isolate ZJHZ (MF590742), and the 657 bp fragment shared 98.9% nucleotide identity with CMV strain K (AF127977). To our knowledge, this is the first report of TYLCV and CMV infecting A. rugosa.

Constant laccase activities were detected in culture supernatant of newly isolated basidiomycete Trametes gallica. Tryptone and glucose have great effects on the production of laccase. Two laccase isoenzymes (Lac I and Lac II) produced by T. gallica were purified to homogeneity (51- and 50-fold, respectively) by gel filtration chromatography, anion exchange chromatography, and improved native PAGE, with an overall yield of 24.8%. Lac I and Lac II from this fungus are glycoproteins with 3.6% and 4% carbohydrate content, the same molecular masses (by SDS-PAGE) of 60 kDa, and the pI of 3.1 and 3.0, respectively. Native gel electrophoresis indicates that the two laccases have different migration ratios. Lac I and Lac II have the same optimal pH of 3.0 on 2,6-dimethoxyphenol (DMP), pH 2.2 on 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and of pH 4.0 on guaiacol. The highest rate of ABTS oxidation for both laccases was reached at 70 degrees C. Both laccases are stable from pH 6 to 9, retaining 88-90% activity after 24 hr incubation, and show good stability when incubated at temperatures lower than 40 degrees C. The Km values of Lac I for ABTS, DMP, and guaiacol are 0.118 x 10(-2), 0.420, and 0.405 mM, respectively; the Km values of Lac II for ABTS, DMP, and guaiacol are 0.086 x 10(-2), 0.41, and 0.40 mM, respectively. Their N-terminal sequences are determined and show strong similarity with those from other basidiomycetes. Graphite-furnace atomic absorption analysis revealed that both laccases have four copper atoms per protein molecule, but they have no type I copper signal at around 600 nm and a type III copper signal near 330 nm. Cyanide, azide, and halides completely inhibit the enzyme activity, whereas EDTA has less inhibition.