Effect analysis of 847 nasopharyngeal carcinoma cases treated with intensity modulated radiation: Experience and suggestions.

OBJECTIVES: To identify the failure patterns and prognostic factors of nonmetastatic nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era. METHODS: Data on 847 patients with newly diagnosed, non-disseminated NPC treated by IMRT between 2012 and 2016 were retrospectively reviewed. Survival outcome, failure patterns and prognosis factors were analyzed. RESULTS: The 5-year local relapse-free survival, nodal relapse-free survival, distant metastasis-free survival, disease-free survival, and overall survival rates were 94.3%, 95.3%, 84.8%, 76.5% and 85.7%, respectively. The major local recurrence sites were the nasopharynx (91.5%, 43/47) and skull base (68.1%, 32/47); 39 patients had in-field failures, four had marginal failures, and four had out-field failures. Level IIb (62.2%, 23/37) was the most frequent regional recurrence site, followed by IIa (35.1%, 13/37) and retropharyngeal region (32.4%, 12/37); 35 cases had in-field failure alone, one had out-field failure alone, and one had both in- and out-field failure. TNM stage was the most significant factor for prognosis prediction. 402 (47.5%) patients had acute adverse events of grade 3 or 4; leukopenia (31.5%) and mucositis (26.7%) was the most common hematological and non-hematological event, respectively. Late complications were slight or moderate damages; xerostomia (647/847, 76.4%) and hearing impairment (422/847, 49.8%) remained the most troublesome. CONCLUSION: NPC patients treated with IMRT obtained satisfactory survival outcomes. The key failure pattern was distant metastasis. The main pattern of local-regional failure was in-field failure. Screening high risk patients with distant metastases and optimizing radiotherapy targets should be studied.

Insights into drought stress response mechanism of tobacco during seed germination by integrated analysis of transcriptome and metabolome.

Drought stress inhibits seed germination, plant growth and development of tobacco, and seriously affects the yield and quality of tobacco leaves. However, the molecular mechanism underlying tobacco drought stress response remains largely unknown. In this study, integrated analysis of transcriptome and metabolome was performed on the germinated seeds of a cultivated variety K326 and its EMS mutagenic mutant M28 with great drought tolerance. The result showed that drought stress inhibited seed germination of the both varieties, while the germination rate of M28 was faster than that of K326 under drought stress. Besides, the levels of phytohormone ABA, GA19, and zeatin were increased by drought stress in M28. Five vital pathways were identified through integrated transcriptomic and metabolomic analysis, including zeatin biosynthesis, aspartate and glutamate synthesis, phenylamine metabolism, glutathione metabolism, and phenylpropanoid synthesis. Furthermore, 20 key metabolites in the above pathways were selected for further analysis of gene modular-trait relationship, and then four highly correlated modules were found. Then analysis of gene expression network was carried out of Top30 hub gene of these four modules, and 9 key candidate genes were identified, including HSP70s, XTH16s, APX, PHI-1, 14-3-3, SCP, PPO. In conclusion, our study uncovered some key drought-responsive pathways and genes of tobacco during seeds germination, providing new insights into the regulatory mechanisms of tobacco drought stress response.

Design, synthesis and antimicrobial evaluation of novel benzoxazole derivatives.

The synthesis of (S)-2-(4-tert-butylphenoxy)-3-(benzoxazol-5-yl) propanoic acid derivatives (2a-k) were described and their in vitro antibacterial activities were determined against Gram-negative and -positive bacteria. These compounds were found to exert a broad spectrum of activity against the screened bacteria, but poor MIC values were found for Candida albicans fungi. Compound 2b bearing a hydrophobic aromatic tie was the most active derivative against all bacteria studied with MIC values ranging from 0.098 to 0.78 µg/mL. The activity of 2b against B. subtilis was 2-fold higher than Penicillin, and 8- to 510-fold higher than other control antibiotics.

Synthesis and antimicrobial evaluation of 3-methanone-6-substituted-benzofuran derivatives.

Seventeen benzofuran derivatives were synthesized and screened for their antibacterial activities against Escherichia coli, Staphylococcus aureus, Methicillin-resistant S. aureus, Bacillus subtilis, and Pseudomonas aeruginosa. Seven of them have showed excellent antibacterial activities compared to the positive controls (Cefotaxime and Sodium Penicillin). The substitutions at C-6 and C-3 positions of these derivatives were found to greatly impact on the antibacterial activity and strains specificity, respectively. Specifically, compounds bearing a hydroxyl group at C-6 (5a, 5b, 5c and 12) offered excellent antibacterial activities against all five above-mentioned strains (MIC(80) = 0.78-12.5 ug/mL), and those with imine (15) and (3, 4, 5-trimethoxyphenyl) methanone (7e), respectively, at C-3 position showed selective activity against S. aureus among five tested strains with great MIC(80) values (3.12-12.5 ug/mL).

Design, synthesis and antimicrobial activity of chiral 2-(substituted-hydroxyl)-3-(benzo[d]oxazol-5-yl)propanoic acid derivatives.

Chiral 2-(substituted-hydroxyl)-3-(benzo[d]oxazol-5-yl)propanoic acid derivatives were synthesized and their antibacterial activities were evaluated against fungus, Gram-negative and Gram-positive bacteria. In general, these compounds showed in vitro activities against all screened Gram-negative and Gram-positive bacteria, but poor MIC values for fungus Candida albicans. Remarkably, the (S)-configuration-substituted phenoxyl side chain on position 2 of propanoic acid exerted excellent antibacterial activity against all screened bacteria. Preliminary structure-activity studies revealed that the hydrophobic substitutes, para-tert-butyl (11r), para-phenyl (11s) and para-benzyloxy (11t) on the phenoxyl side chain displayed best activities against all Gram-negative and Gram-positive bacteria with MIC values between 1.56 and 6.25 µg/mL.

Synthesis and antimicrobial evaluation of new benzofuran derivatives.

Thirteen compounds, based on benzofuran skeleton bearing aryl substituents at its C-3 position through methanone linker, were synthesized and screened for their antibacterial and antifungal activities against four bacteria Escherichia coli, Staphylococcus aureus, Methicillin-resistant S.aureus, Bacillus subtilis, and a fungus Candida albicans. Four hydrophobic benzofuran analogs were found to exhibit favorable antibacterial activities (MIC(80) = 0.39-3.12 µg/mL), which were better than the control drugs.