Biological control of Magnaporthe oryzae using natively isolated Bacillus subtilis G5 from Oryza officinalis roots.

Rice blast, caused by Magnaporthe oryzae, is a major threat to global rice production causing significant crop losses and impacting grain quality. The annual loss of rice production due to this disease ranges from 10% to 30%. The use of biologically controlled strains, instead of chemical pesticides, to control plant diseases has become a research hotspot. In this study, an antagonistic endophytic bacterial strain was isolated from the roots of Oryza officinalis using the traditional isolation and culture methods. A phylogenetic tree based on 16S RNA and whole-genome sequencing identified isolate G5 as a strain of Bacillus subtilis. This isolate displayed strong antagonistic effects against different physiological strains of M. oryzae. After co-culture in LB medium for 7 days, the inhibition rates of the mycelial growth of four strains of M. oryzae, ZB15, WH97, Guy11, and T-39800E were 98.07 ± 0.0034%, 98.59 ± 0.0051%, 99.16 ± 0.0012%, and 98.69 ± 0.0065%, respectively. Isolate G5 significantly inhibited the formation of conidia of M. oryzae, with an inhibition rate of 97% at an OD600 of 2. Isolate G5 was able to provide 66.81% protection against rice blast under potted conditions. Whole-genome sequencing revealed that the genome size of isolate G5 was 4,065,878 bp, including 4,182 coding genes. Using the anti-SMASH software, 14 secondary metabolite synthesis gene clusters were predicted to encode antifungal substances, such as fengycin, surfactin, and bacilysin. The G5 isolate also contained genes related to plant growth promotion. These findings provide a theoretical basis for expounding the biocontrol mechanisms of this strain and suggest further development of biogenic agents that could effectively inhibit rice blast pathogen growth and reduce crop damage, while being environmentally friendly, conducive to ecological development, and a sustainable alternative to chemical pesticides. This study also enriches the relevant research on endophytes of wild rice, which proves that wild rice is a valuable microbial resource bank.

[Analysis of the outcomes of squamous cell carcinoma of maxillary sinus with 3 different comprehensive treatments].

PURPOSE: To study the medium or long-term survival rates of different methods used in the treatment of advanced squamous cell carcinoma of the maxillary sinus (SCMS). METHODS: Patients were treated by one of the following methods: 231 patients were treated with induction chemotherapy, followed by radical resection and radiotherapy (CSR); 128 patients were treated with preoperative irradiation (RS), and 87 patients underwent adjuvant radiotherapy (RSR). A total of 446 cases of SCMS from June 1985 to December 2008 were managed with unscheduled application of the above 3 kinds of treatment options. The dose of 231 patients with CSR and 128 patients with RS was 60-70 Gy/30-35 times/5-7 week and 40-50 gy/20-25 times/4-5 week, respectively. Dose in RSR accounted for half of that in CSR. The number of cases undergoing total resection of maxilla, subtotal resection of maxilla and extended excision of maxilla were 299, 111 and 36, respectively (13 cases had orbital exenteration). The number of patients with therapeutic radical neck dissection, functional neck dissection and supraomohyoid neck dissection were 49, 73 and 56, respectively. The data was analyzed with SPSS16.0 software package. RESULTS: Five-year survival rate in 446 cases was 45.96% (205/446), and 220 patients died of tumors, among which 84.09% (185/220) of death were due to local recurrences. The 5-year survival rate of CSR, RS, and RSR were 45.88% (106/23), 46.09% (59/128) and 45.97% (40/87), respectively; Totally 83.33% of CSR, 85.71% of RS and 83.72% of RSR died of local recurrences. There was no significant difference in the survival rates among CSR, RS and RSR. CONCLUSIONS: Unscheduled comprehensive treatment have a higher 5-year survival rate in this advanced SCMS. Elective neck irradiation and neck dissection are necessary for medium or advanced squamous cell carcinoma of maxillary sinus.

[Grade IV myelosuppression after induction chemotherapy of TPF on oral cancer: clinical analysis of 29 cases].

PURPOSE: To observe and evaluate the clinical features and treatment strategies of IV myelosuppression after induction chemotherapy of oral mucosa squamous cell carcinoma under conventional dosage. METHODS: Twenty-nine patients of oral mucosa squamous cell carcinoma pathologically diagnosed between 2006 and 2012 were enrolled into this study. The patients received induction chemotherapy with docetaxel-cisplatin-5-fluorouracil (TPF) and suffered from grade IV myelosuppression. Regulations and treatment strategies of the bone marrow myelosuppression were analyzed, retrospectively. RESULTS: Twenty-nine cases had bone marrow suppression 9-14 days after induction chemotherapy, and the median time was 10 days, with a "U"-shaped fluctuation pattern. There were 26 cases with colony-stimulating factor(CSF) therapy completing treatment according to the schedule and 2 cases were required to radiotherapy because of unsatisfied effect of CSF therapy. One case died and the death rate after chemotherapy was 0.68% in this group. CONCLUSIONS: The incidence of grade IV myelosuppression is normal and fatal. This study shows the starting time of the "U"-shaped fluctuation and the necessaries of adding CSF therapy at the same time. The emergency treatment of myelosuppression should be used including single disinfected ward mouthwash and therapy of CSF drug.