A gas chromatography mass spectrometry (GC-MS) method has been developed and fully validated for the simultaneous determination of natural borneol (NB) and its metabolite, camphor, in rat plasma. Following a single liquid-liquid extraction, the analytes were separated using an HP-5MS capillary column (0.25 mm ? 30 m ? 0.25μm) and analyzed by MS in the selected ion monitoring mode. Selected ion monitor (m/z) of borneol, camphor and internal standard was 95, 95 and 128, respectively. Linearity, accuracy, precision and extraction recovery of the analytes were all satisfactory. The method was successfully applied to pharmacokinetic studies of NB after oral administration to Wistar rats.

PD-1 and CTLA-4 antibodies offer great hope for cancer immunotherapy. However, many patients are incapable of responding to PD-1 and CTLA-4 blockade and show low response rates due to insufficient immune activation. The combination of checkpoint blockers has been proposed to increase the response rates. Besides, antibody drugs have disadvantages such as inclined to cause immune-related adverse events and infiltration problems. In this study, we developed a cyclic peptide C25 by using Ph.D.-C7C phage display technology targeting LAG-3. As a result, C25 showed a relative high affinity with human LAG-3 protein and could effectively interfere the binding between LAG-3 and HLA-DR (MHC-II). Additionally, C25 could significantly stimulate CD8 T cell activation in human PBMCs. The results also demonstrated that C25 could inhibit tumor growth of CT26, B16 and B16-OVA bearing mice, and the infiltration of CD8 T cells was significantly increased while FOXP3 Tregs significantly decreased in the tumor site. Furthermore, the secretion of IFN- by CD8 T cells in spleen, draining lymph nodes and especially in the tumors was promoted. Simultaneously, we exploited T cells depletion models to study the anti-tumor mechanisms for C25 peptide, and the results combined with MTT assay confirmed that C25 exerted anti-tumor effects CD8 T cells but not direct killing. In conclusion, cyclic peptide C25 provides a rationale for targeting the immune checkpoint, by blockade of LAG-3/HLA-DR interaction in order to enhance anti-tumor immunity, and C25 may provide an alternative for cancer immunotherapy besides antibody drugs.

OBJECTIVE To investigate the effects of individualized dosing regimen on blood trough concentration of vancomycin and renal function in critically ill patients. METHODS According to relevant guidelines and the results of Vancomycin Calculator， clinical pharmacists formulated an individualized dosing regimen of vancomycin including loading dose and maintenance dose for critically ill patients based on the two independent variables of body weight and creatinine clearance rate. Using the method of retrospective study， patients who were admitted to the department of intensive care unit （ICU） of the Second Affiliated Hospital of Guangzhou Medical University and used the regimen from July 2018 to December 2021 were selected as the trial group， and patients who were treated with vancomycin and received blood drug concentration monitoring in ICU from January 2015 to June 2018 were recruited in the control group. The difference in trough concentration distribution and the incidence of acute kidney injury （AKI） after medication were compared between the two groups， the change of serum creatinine before and after medication in the trial group was analyzed. RESULTS Totally 197 patients were included in the trial group and 144 patients were in the control group. There was no significant difference between the two groups in the clinical information （gender， age， body weight， acute physiology and chronic health evaluation Ⅱ score， the proportion of patients with renal insufficiency， etc.） （P＞0.05）. The proportions of major infection sites （including lung， urinary， abdominal， blood and central nervous system） and treatment type （target or empirical treatment） also had no significant difference between the two groups （P＞0.05）. There was no significant difference in the attainment rate of ideal trough concentration （15-20 μg/mL） and the proportion of patients with trough concentration　＞20 μg/mL between the two groups （P＞0.05）， while the attainment rate of target trough concentration （10-20 μg/mL） and the proportion of patients with trough concentration ＜10 μg/mL were significantly different between the two groups （P＜0.05）. The attainment rate of target trough concentration in patients with chronic renal insufficiency in trial group was significantly higher than that in control group （P＜0.05）. There was no significant difference in the incidence of AKI and vancomycin-associated AKI between the two groups （P＞0.05）. In the trial group with medication duration ≥7 days ， the level of serum creatinine on the 7th day of treatment was increased significantly， compared with that on the 3rd day of treatment （P＜0.05）. CONCLUSIONS This individualized dosing regimen can improve the attainment rate of target trough concentration of vancomycin in critically ill patients， especially those with chronic renal insufficiency， during the first standardized monitoring， and not increase the risk of renal injury compared with previous empirical medication.

Tryptophan 2,3-dioxygnease 2 (TDO2) is specific for metabolizing tryptophan to kynurenine (KYN), which plays a critical role in mediating immune escape of cancer. Although accumulating evidence demonstrates that TDO2 overexpression is implicated in the development and progression of multiple cancers, its tumor-promoting role in esophageal squamous cell carcinoma (ESCC) remains unclear. Here, we observed that TDO2 was overexpressed in ESCC tissues and correlated significantly with lymph node metastasis, advanced clinical stage, and unfavorable prognosis. Functional experiments showed that TDO2 promoted tumor cell proliferation, migration, and colony formation, which could be prevented by inhibition of TDO2 and aryl hydrocarbon receptor (AHR). Further experimentation demonstrated that TDO2 could promote the tumor growth of KYSE150 tumor-bearing model, tumor burden of C57BL/6 mice with ESCC induced by 4-NQO, enhance the expression of phosphorylated AKT, with subsequent phosphorylation of GSK3

Developing new therapeutic agents for cancer immunotherapy is highly demanding due to the low response ratio of PD-1/PD-L1 blockade in cancer patients. Here, we discovered that the novel immune checkpoint VISTA is highly expressed on a variety of tumor-infiltrating immune cells, especially myeloid derived suppressor cells (MDSCs) and CD8⁺ T cells. Then, peptide C1 with binding affinity to VISTA was developed by phage displayed bio-panning technique, and its mutant peptide VS3 was obtained by molecular docking based mutation. Peptide VS3 could bind VISTA with high affinity and block its interaction with ligand PSGL-1 under acidic condition, and elicit anti-tumor activity in vivo. The peptide DVS3-Pal was further designed by d-amino acid substitution and fatty acid modification, which exhibited strong proteolytic stability and significant anti-tumor activity through enhancing CD8⁺ T cell function and decreasing MDSCs infiltration. This is the first study to develop peptides to block VISTA/PSGL-1 interaction, which could act as promising candidates for cancer immunotherapy.