Based on amino acid score of food, this article presents an "Amino Acid Score Difference (AASD) " for protein quality evaluation, the minus value of AASD representing the limiting amino acid and its number re- presenting the degree. The minus value in one food can be compensated by the positive value in another when we directly select the rational couple for amino acid complementation in diet. In addition, a calculation formula is introduced for amino acid complementation in two kinds of food or in mixed diet including many foods. It gives an effective means in evaluating the nutritional value of protein in foods and planning an ideal diet by selecting foods on the basis of amino acid complementation

Objective:To investigate the efficacy and safety of fractionated stereotactic radiotherapy (FSRT) based on linear accelerator for small volume brain metastases.Methods:A total of 21 patients with small volume brain metastases who received FSRT from August 2020 to June 2022 were enrolled as subjects, including 45 lesions. Small-volume brain metastases were defined as ≤3 cm in diameter and ≤6 cm 3 in volume, and the dose/fractionation scheme was 27-30 Gy/3 F or 30-40 Gy/5 F. Three months after radiotherpy, the efficacy of FSRT in small brain metastases and the incidence of radiation brain injury were evaluated, and the incidence of radiation brain injury in subgroup analysis was performed according to the diameter, volume, dose/fractionation scheme, biological effective dose (BED) 10, and location of lesions. Results:Twenty-four lesions (53.33%, 24/45) were evaluated as complete response, another 13 lesions (28.89%, 13/45) were evaluated as partial response, and in the remaining 8 lesions (17.78%, 8/45) were evaluated as stable disease. The local control rate was 100% (45/45), the objective remission rate was 82.22% (37/45), and the intracranial distant progression rate was 23.81% (5/21). During the treatment and follow-up, there were 7 lesions (15.56%, 7/45) of radiation-induced brain injury, and the incidence of symptomatic radiation-induced brain injury was 11.11% (5/45). Subgroup analysis showed that the incidence of radiation brain injury in the group with a lesion diameter of 2-3 cm was higher than that with a lesion diameter of <2 cm group, with a statistically significant difference [80.00% (4/5) vs. 7.50% (3/40), χ2=12.69, P<0.001]; the incidence rate of radiation brain injury in the group with lesion volume of 4-6 cm 3 was higher than that with lesion volume of <4 cm 3 group, with a statistically significant difference [57.14% (4/7) vs. 7.89% (3/38), χ2=7.49, P=0.006]. There was no significant difference in the incidence of radiation brain injury between the dose/fractionation scheme of lesions 27-30 Gy/3 F and 30-40 Gy/5 F [9.52% (2/21) vs. 20.83% (5/24), χ2=0.40, P=0.527]. There was no significant difference in the incidence of radiation brain injury between the BED 10<60 Gy and ≥60 Gy [28.57% (2/7) vs. 13.16% (5/38), χ2=0.22, P=0.641]. There was no significant difference in the incidence of radiation brain injury between the lesions in the same lobe and the single or multiple lesions in different lobes [28.57% (4/14) vs. 9.68% (3/31), χ2=1.38, P=0.240) . Conclusion:FSRT based on linear accelerator is effective for small volume brain metastases. Brain metastases with the diameter <2 cm or volume <4 cm 3 are associated with a lower incidence of radiation brain injury than that of lesions with the diameter of 2-3 cm or volume of 4-6 cm 3.

Objective:To evaluate clinical efficacy of adjuvant radiotherapy (RT) for central neurocytoma (CN) after surgical resection.Methods:Clinical data of 136 CN patients admitted to Beijing Tiantan Hospital and Xuanwu Hospital from January 2001 to December 2020 were retrospectively analyzed. Preliminary interventions consisted of craniotomy (gross total resection, subtotal resection and partial resection, the latter two belonging to incomplete resection) and postoperative radiotherapy. Three-dimensional conformal or intensity-modulated radiotherapy was adopted, with a median radiotherapy dose of 54 Gy. Post-recurrence treatment included salvage surgery and radiotherapy. The overall survival (OS) and progression-free survival (PFS) were analyzed using the Kaplan-Meier method. Univariate analysis was performed by log-rank test to evaluate the effect of each prognostic factor on OS and PFS. The effects of multiple prognostic factors on PFS and OS were assessed by Cox regression model.Results:The median age was 28 years (range: 6-66 years). The median follow-up was 94.5 months (12-237 months). Among all patients, 79 cases underwent total resection, and 68 of them received adjuvant radiotherapy. Thirty-eight patients underwent subtotal resection, and 37 of them were treated with adjuvant radiotherapy. Sixteen patients received partial resection and adjuvant radiotherapy. Three cases received biopsy and postoperative radiotherapy. Among all patients, 3 cases died, including 2 from tumor recurrence and 1 from postoperative complication. Eight patients had recurrences during follow-up. Among them, 7 patients had recurrences at the primary site,1 had tumor dissemination to the spinal cord. The 5- and 10-year OS rates were 98.5% and 96.8%, and the 5- and 10-year PFS rates were 95.3% and 91.6% for the in the entire cohort. In the gross total resection without radiotherapy group, the 5- and 10-year PFS rates were 90.9% and 90.9%, and 96.6% and 96.6% in the gross total resection + radiotherapy group ( P=0.338). The 5- and 10-year OS rates were 100% and 100% in the gross total resection without radiotherapy group, and 98.5% and 98.5% in the gross total resection + radiotherapy group ( P=0.693). The 10-year PFS rates between the gross total resection±radiotherapy group and the incomplete resection+radiotherapy group was 95.8% vs. 90.3% ( P=0.368), and the 10-year OS rate was 98.6% vs. 94.7% ( P=0.436). Multivariate analysis showed that tumor site, degree of surgical resection, adjuvant radiotherapy and age exerted no significant effects on PFS and OS. A total of 81 patients had late neurotoxicities, including 69 cases at grade 1, 9 cases at grade 2, and 3 cases at grade 3. And 64.2% (52/81 cases) of patients suffered from short-term memory impairment. Conclusions:Gross total resection alone yields high efficacy for CN. Postoperative radiotherapy is not required. Incomplete resection combined with postoperative adjuvant radiotherapy can achieve equivalent clinical efficacy to gross total resection.