Unexpected mutations occurred in CRISPR/Cas9 edited Drosophila analyzed by deeply whole genomic sequencing.

CRISPR/Cas9 possesses the most promising prospects as a gene-editing tool in post-genomic researches. It becomes an epoch-marking technique for the features of speed and convenience of genomic modification. However, it is still unclear whether CRISPR/Cas9 gene editing can cause irreversible damage to the genome. In this study, we successfully knocked out the WHITE gene in Drosophila, which governs eye color, utilizing CRISPR/Cas9 technology. Subsequently, we conducted high-throughput sequencing to assess the impact of this editing process on the stability of the entire genomic profile. The results revealed the presence of numerous unexpected mutations in the Drosophila genome, including 630 SNVs (Single Nucleotide Variants), 525 Indels (Insertion and Deletion) and 425 MSIs (microsatellite instability). Although the KO (knockout) specifically occurred on chromosome X, the majority of mutations were observed on chromosome 3, indicating that this effect is genome-wide and associated with the spatial structure between chromosomes, rather than being solely limited to the location of the KO gene. It is worth noting that most of the mutations occurred in the intergenic and intron regions, without exerting any significant on the function or healthy of the animal. In addition, the mutations downstream of the knockout gene well beyond the upstream. This study has found that gene editing can lead to unexpected mutations in the genome, but most of these mutations are harmless. This research has deepened our understanding of CRISPR/Cas9 and broadened its application prospects.

Excavation and evaluation of adverse reaction signals of 4 kinds of imported PD- 1/PD-L1 inhibitors / 中国药房

OBJECTIVE To exc avate and evaluate the adverse reaction signals of 4 kinds of imported programmed cell death 1 （PD-1）and its ligand （PD-L1）inhibitors，and to guide rational drug use in clinic. METHODS OpenVigil 2.1 software was used to obtain the adverse event reports of four drugs as nivolumab ，pembrolizumab，atezolizumab and durvalumab from the first quarter of 2013 to the fourth quarter of 2020 in the US FDA adverse event reporting system. The reporting odds ratio and proportional reporting ratio were used for signal mining to evaluate new or potential adverse reaction signals. RESULTS A total of 46 840 reports of adverse events with PD- 1/PD-L1 inhibitors as the primary suspected drug were collected ，including 28 896 reports of nivolumab，13 298 reports of pembrolizumab ，3 398 reports of atezolizumab ，and 1 248 reports of durvalumab. From the general characteristics of these reports ，the gender distribution was more men than women ，and the age distribution was mainly in the range of 51-85 years old. The reporting year was mainly in the nearly 4-5 years，and the main reporting countries were the US and Japan，with“death”and“hospitalization or prolonged hospitalization ”as the main serious adverse events which were over 50％ of the whole of 4 kinds of adverse events. A total of 1 597 adverse reaction signals were obtained ，involving 26 systems，focusing on “benign，malignant and unspecified neoplasms （cystic and polypoid tumor ）”，“infections and infestations ”and“investigations”， etc. The analysis of the top 50 adverse reaction signals showed that the largest number of report was endocrine system disease ，the most frequency signal was “malignant neoplasm progression ”and the strongest adverse reaction signal was “radiation pneumonitis ”. And it was also found that 13 adverse reaction signals ，such as “radiation pneumonitis ”“cholangitis”“fulminant type 1 diabetes mellitus” “blood creatine phosphokinase increased ” “disseminated intravascular coagulation ”“cardiac failure ”and “cerebral infarction ”，etc.，were not reported in the drug instructions. CONCLUSIONS PD-1/PD-L1 inhibitors mediate a large number of adverse reaction signals，resulting in high safety risks in “benign，malignant and unspecified neoplasms （cystic and polypoid tumor ）”，“infections and infestations ”and “investigations”，etc. The newly discovered 13 adverse reaction signals ，such as “radiation pneumonitis ”“cholangitis”“blood creatine phosphokinase increased ”“cardiac failure ”and“cerebral infarction ”are of great significance for guiding rational drug use in clinic.

Genetic quality analysis of 24 domestic inbred mouse strains by microsatellite DNA / 中国比较医学杂志

Objective To analyze the genetic quality of 24 domestic inbred strains mice using microsatellite loci panel.Methods Previously selected 30 microsatellite loci of mouse with high polymorphism and more allele numbers were used to synthesize corresponding fluorescently-labeled primers.Then the genomic DNA samples of each mouse were amplified by PCR and the products were analyzed by STR scanning to genotype the inbred strains of mice.Results Out of the 24 inbred strains, 15 inbred strains showed the same genotype within one strain at 30 loci.Among different strains, microsatellite loci indicated polymorphism which could be used to distinguish different strains.However, the rest 9 strains demonstrated polymorphism within strains.Conclusions Our stuoly provides a useful microsatellite panel to detect genetic quality of inbred mice and distinguish different strains with the optimized microsatellite loci.

Establishment of a detection method for Helicobacter pylori in living Mongolian gerbil / 中国比较医学杂志

Objective To establish a detection technique for H.pylori(HP) infection in Mongolian gerbils using nested PCR technique.Methods H.pylori was cultured in vitro and inoculated into Mongolian gerbils.At the 10th week after infection, the HP in the gastric juice of Mongolian gerbil was detected by conventional PCR assay and the gastric juice, gastric mucosa, duodenal contents and colon stool were examined by nested PCR.Rapid urease test and ELISA were used to analyze the accuracy of the nested PCR assay.All of the PCR products were verified by sequencing.Results The positive rate of gastric juice detected by conventional PCR was 30%, while the positive rates of gastric juice, gastric mucosa, duodenal contents and colon stool detected by nested PCR were 100%, 100%, 90%, and 10%, respectively.The positive detection rates of rapid urease test and serum ELISA were 100% and 0%, respectively.Comparing the results of different methods, both the positive rates of gastric juice and gastric mucosa detected by nested PCR and the detection rate of rapid urease test were 100%, but the results of conventional PCR detection of gastric juice, the nested PCR detection result of stool in colon and of serum ELISA assay were lower than other methods.Conclusions Due to its high accuracy and sensitivity, the nested PCR assay of gastric juice can be used for the long-time detection of H.pylori infection in Mongolian gerbils, especially useful in the experiments of prevention and treatment of H.pylori infection.

The optimization scheme of Mongolian gerbils superovulation induced by PMSG and hCG / 中国比较医学杂志

Objective To optimize the scheme of Mongolian gerbil superovulation.Methods Based on the analysis of the animal-week-old, the dose and time interval of hormone, we got the best animal-week-old, dose and time interval of hormone for Mongolian gerbil superovulation.Results The 6 week old female Mongolian gerbils which injected of 10 IU PMSG and followed by 10 IU hCG in 70 hours later could get the best superovulation.We collected eggs at 16 hour after mate with male gerbils.The ovum pick-up rate reached 80%, the number of oocytes were 32.6 ±3.0, the number of the fertilized egg developed to 2-cell are 24.8 ±5.4.Conclusions This study summarizes the optimization scheme of Mongolian gerbil superovulation induced by PMSG and hCG and it supported the foundation for Mongolian gerbils embryo biotechnology.

Advances in development and application of Mongolian gerbil resource / 中国实验动物学报

Mongolian gerbil is a multifunctional laboratory anima1 resource with Chinese characteristics.It has many advantages for some research fields, and play an important role.The more biological characteristics of Mongolian ger-bils discovered with in-depth research will promote diverse application of this resoure.In this paper, we reviewed the devel-opment of application of Mongolian gerbils in taxonomy, parasitology, microbiology, cerebral ischemia, lipid metabolism, neurological diseases, and cancer researches.

Comparison of domestic idataubicin and imported daunorubicin on the treatment of acute leukemia / 白血病·淋巴瘤

Objective To compare the effect and toxicity of domestic idarubicin (IDA) and imported daunorubicin (DNR) in the treatment of acute leukemia (AL).Methods According to the random number table method,68 patients were randomly divided in IDA group with 35 patients and DNR group with 33 patients.In IDA group,the patients with acute myelocytic leukemia were treated following IA scheme (domestic idataubicin plus cytosine arabinoside) and the patients with acute lymphoblastic leukemia were treated following VICLP scheme (vincristine,domestic idataubicin,cyclophosphamide,lasparaginase and prednisone).In DNR group,the patients with acute myelocytic leukemia were treated following DA scheme (imported daunorubicin plus cytosine arabinoside) and the patients with acute lymphoblastic leukemia were treated following VDCLP scheme (vincristine,imported daunorubicin,cyclophosphamide,lasparaginase and prednisone).Results In IDA group,21 patients achieved a complete remission(CR),5 patients achieved a partial remission(PR),with a 74.2 ％ (26/35) remission rate (RR).In DNR group,the remission rate was 62.3 ％ (20/33).No differences of the remission rate was found between the two groups (t =0.89,P =0.50).17 patients were found remission over one year in IDA group,and 6 patients were in DNR group.The difference was statistically significant between the two groups (x2 =5.56,P =0.02).Conclusion IDA is more effective than DNR in AL treatment.The higher RR and longer remission time are found in IDA group than DNR group.IDA is effective and safe in the treatment of AL.

Transgene complete silencing may associate with rearrangement of retroviral vector / 生物医学工程学杂志

Transgene silencing is one of two major obstacles in both basic biomedical research for transgene and clinical practice of gene therapy. Based on the model of HT1080 cell clones, which transduced single copy of retroviral vector MGPN2, the mechanism of transgene silencing was explored in this investigation by a serial molecular techniques. In the HT1080 cell clone that absence of GFP protein synthesized, no significant aberration of epigenetic modification was detected, but the transcript size and the sequence changed that resulted in the reading frame shift. In addition to chromosomal position effect leading to transgene silencing, the transcript reading frame shift associated with retroviral vector rearrangements could induce complete silencing of transgene.

6-O-Angeloylenolin induces apoptosis through a mitochondrial/caspase and NF-kappaB pathway in human leukemia HL60 cells.

6-O-Angeloylenolin, a sesquiterpene lactone from Centipeda minima, has been known to have anti-tumor activity against human colorectum, liver, stomach, lung, and skin tumor cells. However, its molecular mechanism is still obscure and insufficient in in vivo tests. In this study, we demonstrated that 6-O-angeloylenolin could induce apoptosis in human leukemia HL60 cells through stimulating the generation of reactive oxygen species, decreasing mitochondrial trans-membrane potential (DeltaPsim) and activating caspase-3/7. We also found that 6-O-angeloylenolin could inhibit nuclear translocation of NF-kappaB and modulate the expression of Bcl-2 gene family. These results indicated that 6-O-angeloylenolin induces apoptosis by inhibition of NF-kappaB activation, modulation of Bcl-2 gene family expression and destruction of mitochondrial function. Furthermore, we confirmed that 6-O-angeloylenolin could obviously inhibit the solid cancer growth in Lewis lung cancer xenograft models.