Safety and efficacy of a programmed cell death 1 inhibitor combined with oxaliplatin plus S-1 in patients with Borrmann large type III and IV gastric cancers

BACKGROUND Gastric cancer(GC)is the fifth most common and the fourth most lethal malignant tumour in the world.Most patients are already in the advanced stage when they are diagnosed,which also leads to poor overall survival.The effect of posto-perative adjuvant chemotherapy for advanced GC is unsatisfactory with a high rate of distant metastasis and local recurrence.AIM To investigate the safety and efficacy of a programmed cell death 1(PD-1)inhibitor combined with oxaliplatin and S-1(SOX)in the treatment of Borrmann large type III and IV GCs.METHODS A retrospective analysis(IRB-2022-371)was performed on 89 patients with Borrmann large type III and IV GCs who received neoadjuvant therapy(NAT)from January 2020 to December 2021.According to the different neoadjuvant treatment regimens,the patients were divided into the SOX group(61 patients)and the PD-1+SOX(P-SOX)group(28 patients).RESULTS The pathological response(tumor regression grade 0/1)in the P-SOX group was significantly higher than that in the SOX group(42.86%vs 18.03%,P=0.013).The incidence of ypN0 in the P-SOX group was higher than that in the SOX group(39.29%vs 19.67%,P=0.05).The use of PD-1 inhibitors was an independent factor affecting tumor regression grade.Meanwhile,the use of PD-1 did not increase postoperative complications or the adverse effects of NAT.CONCLUSION A PD-1 inhibitor combined with SOX could significantly improve the rate of tumour regression during NAT for patients with Borrmann large type III and IV GCs.

Comparison of RFFIT Tests with Different Standard Sera and Testing Procedures

The World Health Organization (WHO) standard assay for determining antibody level is the rapid fluorescent focus inhibition test (RFFIT) and is used to determine the degree of immunity after vaccination against rabies. To compare the difference in RFFIT results between the laboratories of The National Institute of Infectious Disease in Japan (NIID) and the Chinese Centre for Disease Control (CCDC) as well the influence of the choice of standard serum (STD) for the detection, the two laboratories detection methods were simultaneously manipulated by RFFIT. The reference serums used in NIID and the WHO standard serum used in CCDC were compared in the same RFFIT detection to determine the titer of four sera samples C1, S1, S2 and S4 in parallel, and the titers of the detected sera samples were calculated using the standard formula for neutralizing antibody titer. No significant difference was found in RFFIT methods from the two laboratories and the RFFIT testing procedures of the two laboratories have good consistency. However, different titers were obtained with the tentative internal standard serum (TI-STD) produced by adjusting to 2.0 IU of WHO standard serum in NIID and the WHO STD. The titer determined with the TI-STD was higher than that determined with WHO STD, This difference appears to be significant and requires further investigation.

Preparation and Identification of Anti-rabies Virus Monoclonal Antibodies

To provide a foundation for the development of rapid and specific methods for the diagnosis of rabies virus infection, anti-rabies virus monoclonal antibodies were prepared and rabies virus nucleoprotein and human rabies virus vaccine strain (PV strain) were used as immunogens to immunize 6-8 week old female BALB/c mice. Spleen cells and SP2/0 myeloma cells were fused according to conventional methods: the monoclonal cell strains obtained were selected using the indirect immunofluorescence test; this was followed by preparation of monoclonal antibody ascitic fluid; and finally, systematic identification of subclass, specificity and sensitivity was carried out. Two high potency and specific monoclonal antibodies against rabies virus were obtained and named 3B12 and 4A12, with ascitic fluid titers of 1:8000 and 1:10000, respectively. Both belonged to the IgG2a subclass. These strains secrete potent, stable and specific anti-rabies virus monoclonal antibodies, which makes them well suited for the development of rabies diagnosis reagents.

通道S1–S4显著的动态变化而非静止状态是香草素类配体激活TRPV1的关键因素

瞬时受体电位香草素1(TRPV1)通道参与了哺乳动物体内许多重要的生理和病理过程,对其门控机制的全面了解有助于为相关疾病的治疗干预提供可能.近年来冷冻电子显微镜(cryo-EM)技术在结构生物学中取得了惊人的成果,所有TRPV亚型(TRPV1±6)的高分辨率结构也得到了解析:它们都具有高度保守的6个跨膜(TM)结构域(S1±S6),与电压门控离子通道(VGICs)相似.并且,在结合了香草素激动剂(辣椒素或树脂毒素)的TRPV1通道开放结构中,TM螺旋S1±S4形成一束,保持静止状态,这也证明了TRP和VGICs通道功能和门控机制的差异.然而,本研究认为S1±S4的动态变化而非静止是辣椒素激活TRPV1的必要条件.通过荧光非天然氨基酸结合和电压钳荧光测量分析,本研究直接观察到辣椒素结合后S1±S4域的运动.电压钳荧光测量法(VCF)所识别位点的化学修饰、单通道记录、细胞凋亡分析和对一种新激动剂PSFL828作用的探索,共同证实了这种协调的S1±S4运动在辣椒素介导的TRPV1激活中的重要作用.这项研究提出了一个新的见解:与冷冻电镜结构研究的结论不同,香草素激动剂在TRPV1激活过程中也需要S1±S4运动.本文重新定义香草素类激动剂的门控过程并发现了新的非香草素类激动剂,为开发TRPV1调节剂提供了新策略.

Human rabies in China:evidence-based suggestions for improved case detection and data gathering

Background:China still suffers heavily from rabies,although reported human cases continue to decrease year over year.There are far fewer laboratory-confirmed human cases than clinically diagnosed cases,which is a big problem that needs to be addressed.In this report,we summarize analyses of all specimens from human cases tested in our laboratory over the past 15 years,in order to promote laboratory diagnosis of rabies.Methods:From 2005 to 2019,a total of 271 samples from 164 suspected rabies cases were collected from local hospitals by the local Centers for Disease Control and Prevention(CDCs)in China.Saliva,cerebrospinal fluid(CSF),serum(blood)and urine were collected for ante-mortem diagnosis,and brain tissue,neck skin tissue and cornea were collected for post-mortem diagnosis.All of the specimens were tested by reverse transcription-polymerase chain reaction(RT-PCR),and brain tissues were also tested using fluorescent antibody test(FAT).The number of positive test results obtained using different fluids or tissues,and at different stages of the disease,were compared using a chi-square test and a more effective sampling program is recommended.Results:As the national reference laboratory for rabies surveillance in China,our laboratory has tested 271 samples from 164 suspected rabies cases collected by local CDCs since 2005.We found that saliva gave the highest number of positive test results(32%),compared with CSF and other fluids.We also found that serum or blood specimens collected in the last 3 days of life can test positive by RT-PCR.Conclusions:Serum or blood samples collected in the last 3 days of a patient’s life can be used to measure viral RNA,which means that serum samples,as well as saliva and CSF,can be used to detect viral RNA for anti-mortem diagnosis of rabies.Because of our findings,we have modified our“National Surveillance Project for Human Rabies”,by adding the collection and testing of serum samples from the end of the survival period.This will improve our national surveillance and laboratory diagnosis of human rabies.

Establishment of a Chinese street rabies virus library and its application for detecting neutralizing activity

Background:The injection of rabies immune globulin(RIG)is of the utmost importance in the management of category III exposures to rabies-suspect animals.Because of the high cost and limited availability of existing RIG,one possible replacement for RIG is monoclonal antibodies(MAbs)against the rabies virus(RABV).Consequently,it is necessary to determine the neutralizing activity of the MAbs against rabies viruses,especially street rabies virus.However,the method to detect the neutralizing activity of MAbs against street rabies virus remains undefined.Methods:To establish a method for detecting the neutralizing activity of MAbs against street rabies virus,we constructed a library consisting of 12 strains of street RABV from 11 provinces in China.Using this street RABV library and the Reed-Muench formula,we established a method for detecting the neutralizing titer of the MAbs.The reliability and repeatability of the method were evaluated by repeatedly measuring the neutralizing activity of a MAb and a post vaccination serum.Results:A total of 12 strains of street RABV were chosen for inclusion in the street RABV library,which covered six Chinese lineages(China I-China VI)and grew to high titers in N2A cells(>105 FFD50/ml).On the basis of the library,we constructed the method to detect the neutralizing activity of the MAbs.The results of repeatedly measuring the MAbs and positive serum showed excellent reliability and repeatability of the method established in this study.Conclusions:This study established a street RABV library reflecting the epidemiological features of Chinese rabies viruses,which provides a platform for detecting the neutralizing activity of MAbs against rabies viruses circulating in China.