Coronavirus infection can cause serious respiratory and digestive system diseases in hu-mans and animals.In recent years,the frequent outbreaks and newly outbreaks of coronavirus in-fection have threatened global public health and the development of livestock and poultry.Howev-er,the development of anti-coronavirus drugs and vaccines was restricted due to the insufficient understanding of the mechanisms of coronavirus pathogenesis and cross species transmission.Re-verse genetic manipulation technology is a powerful tool in virological research,which can be used for the study of pathogenesis mechanisms,replication mechanisms and function analysis of protein.It is also be used in the development of attenuated or gene labeled vaccines,and antiviral drugs.Due to the large genome and complex structure of the coronavirus,the reverse genetic manipulation technology of coronavirus has been lagging for a long time.With the continuous updating of molec-ular biology methods,various new construction strategies have emerged.This article focuses on the construction strategy of the reverse genetic operating system for coronavirus,as well as its applica-tion in virus transmission and pathogenic mechanisms,and development of vaccines,which will provide favorable tools for the prevention and control of the coronavirus infection.

As a novel and promising antitumor target, AXL plays an important role in tumor growth, metastasis, immunosuppression and drug resistance of various malignancies, which has attracted extensive research interest in recent years. In this study, by employing the structure-based drug design and bioisosterism strategies, we designed and synthesized in total 54 novel AXL inhibitors featuring a fused-pyrazolone carboxamide scaffold, of which up to 20 compounds exhibited excellent AXL kinase and BaF3/TEL-AXL cell viability inhibitions. Notably, compound 59 showed a desirable AXL kinase inhibitory activity (IC₅₀: 3.5 nmol/L) as well as good kinase selectivity, and it effectively blocked the cellular AXL signaling. In turn, compound 59 could potently inhibit BaF3/TEL-AXL cell viability (IC₅₀: 1.5 nmol/L) and significantly suppress GAS6/AXL-mediated cancer cell invasion, migration and wound healing at the nanomolar level. More importantly, compound 59 oral administration showed good pharmacokinetic profile and in vivo antitumor efficiency, in which we observed significant AXL phosphorylation suppression, and its antitumor efficacy at 20 mg/kg (qd) was comparable to that of BGB324 at 50 mg/kg (bid), the most advanced AXL inhibitor. Taken together, this work provided a valuable lead compound as a potential AXL inhibitor for the further antitumor drug development.

Objective The present study aimed to establish a bone mineral density (BMD) reference database in China and to investigate the prevalence of osteoporosis in Chinese adults aged 50 years and older using dual energy X-ray absorptiometry (DXA). Method A total of 75321 examineers over 25 years old who underwent health checkups in 7 health check centers between 2008 and 2018 were included. All centers used a GE Lunar-DXA system to measure BMD of the lumbar spine (L1-L4), femoral neck, and total femur. The same European Spine Phantom (ESP) was used for scanning 10 times at every center, a regression equation was generated, and BMD data were cross-calibrated in each center. Peak BMD and standard deviation (SD) were identified according to 5-year age groups, and T scores were calculated based on the peak BMD and SD. Osteoporosis was defined according to the World Health Organization criteria. The prevalence of osteoporosis was standardized based on 2010 national census data for the Chinese population. Result The mean BMD values decreased with age, were highest in North China, followed by Northeast China, East China, and Southwest China, respectively, and increased with body mass index. Males aged 20-30 years and females aged 35-40 years had peak BMD values. Peak BMD values of the lumbar spine, femoral neck, and total femur were 1.09 g/cm2, 0.97 g/cm2, and 0.97 g/cm2 in males, and 1.11 g/cm2, 0.84 g/cm2, and 0.88 g/cm2 in females, respectively. Among all scanned sites, the prevalence of osteoporosis was highest in the femoral neck in males (4.58％) and in the lumbar spine in females (23.38％). The age-standardized prevalence of osteoporosis at any site was 6.46％ in males and 29.13％ in females aged 50 years and older. Based on the 2010 national census data, 10879115 males and 49286542 females currently have osteoporosis. Conclusion Mean BMD values varied according to geographic region, body mass index, age group, and sex in Chinese adults. The age-standardized prevalence of osteoporosis was 6.46％ in males and 29.13％ in females aged 50 years and older.

Objective To establish the cardiac arrest (CA) model in rats by modified transcutaneous electrical stimulation on epicardium. Methods This study was performed in the Emergency Medicine laboratory in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. After 10 Sprague-Dawley male rats weighing 330-380 g were anesthetized, two acupuncture needles connected to the anode and cathode of a stimulator were transcutaneously inserted into the epicardium as electrodes. The puncture points were located quantitatively according to the anatomical structure of the rat chest. The electrical stimulation was maintained for 3 minutes to induce ventricular fibrillation(VF). Cardiopulmonary resuscitation (CPR) included chest compressions, intravenous adrenaline and defi brillation operated at 6 min after a period of nonintervention. Results CA was induced after the implement of the effective electrical stimulation in all ten rats in this experiment. The average current intensity to induce VF was (1.80 ± 0.59) mA, the average time to induce CA was (5.07 ± 2.37)s,the average time of the total electrical stimulation was(187.50 ± 12.75)s and the total time of CA was 6 min. At the end of the electrical stimulation, 9 rats presented VF and 1 rat showed pulseless electrical activity. The restoration of spontaneous circulation was achieved in all 10 rats. The average time of CPR was(190.90±68.60) s, the mean numbers of defi brillation were(1.20 ± 0.63) , and he average number of adrenaline application were (1.20 ± 0.42) times. Neither visible hemorrhage on epicardium nor gross pulmonary congestion was observed. Conclusions The modified transcutaneous electrical stimulation on epicardium to produce CA model in rats is an easily applicable and effective technique. This model may provide an alternative for experimental research of CPR.

Objective:To establish a three-dimensional quantitative structure-activity relationship (3D-QSAR) model for thiazide 11β-hydroxy steroid dehydrogenase ( HSD) inhibitors in order to perform structure modification and find thiazide 11β-HSD inhibitors with more activity. Methods: The 3D-QSAR model of thiazine derivatives was constructed by the method of comparative molecular force field analysis, and the model was validated by using a molecular docking method. Results:An accurate 3D-QSAR model of 11β-HSD inhibitors was obtained (CoMFA:q2 =0. 346, r2 =0. 850, where q2 was the cross-validation coefficient and r2 was the non-cross validation coefficient) . Conclusion:The results provide important theoretical basis for the rational design of novel thiazide 11β-HSD inhibitors.

Background and objective Progesterone and adiponectin receptor family member 3 (PAQR3) is a recently discovered tumor suppressor gene,which affects the development of a tumor by inhibiting cell proliferation,cell malignant transformation,angiogenesis,and tumor metastasis.This study investigates the expression of PAQR3 in lung cancer and its clinical significance.Methods A total of 106 patients with lung cancer received surgical treatment in hospital,and adjacent normal tissues of these patients were utilized as control group.The diagnosis of all patients was confirmed through clinical pathology.The expression of PAQR3 protein was detected by immunohistochemistry in lung cancer and adjacent normal tissues.The clinical significance of its expression was also investigated.Results The positive expression rate of PAQR3 protein in lung cancer was lower than that in adjacent normal tissues (P＜0.01).The positive expression rate of PAQR3 protein was unrelated to age,tumor size,and gender,but it exhibited a significant relationship with the pathological type and differentiation,TNM staging,and lymph node metastasis (P＜0.05).Kaplan-Meier survival analysis showed that the five-year survival rate of patients with PAQR3 protein positive expression was higher than that in patients with negative expression (P=0.026).Conclusion The expression of PAQR3 protein significantly decreased in lung cancer,indicating that PAQR3 protein plays an important role in the pathogenesis of PAQR3 in lung cancer.

OBJECTIVETo investigate the expressions of serine-threonine kinase (Akt)/mammalian target of rapamycin (mTOR)/p70 S6K in oral squamous cell carcinoma (OSCC) and provide references for early diagnosis and prognosis evalua- tion of OSCC.

METHODSA total of 51 cases of OSCC, 10 cases of paracancerous mucosa, and 10 cases of normal oral mucosa were collected. The expressions of Akt/mTOR/p70 S6K in these cases were detected using the SP method of immunohisto- chemistry. The correlation between their expressions in OSCC was also analyzed.

RESULTSThe positive expressions ofp-Akt, p-mTOR, and p70 S6K in OSCC were significantly higher than those in normal oral mucosa and paracancerous mucosa. The expressions of p-Akt, p-mTOR, and p70 S6K in OSCC were not correlated with age, gender, and clinical stage; by comparison, these expressions were correlated with lymph node metastasis and pathological grade. Strong positive correlations were also observed between the expressions ofp-Akt, p-mTOR, and p70 S6K in OSCC.

CONCLUSIONAkt/mTOR/p70 S6K signaling molecules exhibit active expressions in OSCC and may be implicated in the occurrence and development of OSCC.

Aged ; Animals ; Humans ; Mouth Neoplasms ; Neoplasms, Squamous Cell ; Phosphorylation ; Protein Kinases ; Protein-Serine-Threonine Kinases ; Proto-Oncogene Proteins c-akt ; Ribosomal Protein S6 Kinases, 70-kDa ; Signal Transduction ; Sirolimus ; TOR Serine-Threonine Kinases

Objective To investigate the effects of the head peripheral nerve block on remifentanil consumption and postoperative pain in patients undergoing craniocerebral surgery. Methods 80 patients under general anesthesia undergoing supratentorial craniocerebral surgery were randomly divided into two groups:the head peripheral nerve block combined intravenous anesthesia group (group S, 40 cases) and the simple intravenous anesthesia group (group C, 40 cases). After anesthesia induction intubation, the patients in group S received the head peripheral nerve block with 0.596% ropivacaine mesylate injection,including supraorbital nerve, supratrochlear nerve , auriculotemporal nerve , great occipital nerve and lesser occipital nerve , as well as regional nerve on the corresponding position of the bilateral head nails. Haemodynamic index of the operations was measured;drug consumption during operation and VAS pain score at 0. 5, 2, 6, 12, 24 and 48 h after surgery were recorded. Results Compared with group C, the values of SBP, DBP, HR had a significant decrease at head-nail insertion and the latter stage in group S(P<0.05). The remifentanil consumption and VAS scores had a significant decrease in group S (P < 0.05). Conclution Head peripheral nerve block before operation could enhance anesthesic analgesia, reduce the remifentanil consumption and postoperative pain in patients undergoing craniocerebral surgery.

Objective To investigate the expressions of serine-threonine kinase (Akt)/ mammalian target of rapamycin (mTOR)/p70 S6K in oral squamous cell carcinoma (OSCC) and provide references for early diagnosis and prognosis evalua-tion of OSCC. Methods A total of 51 cases of OSCC, 10 cases of paracancerous mucosa, and 10 cases of normal oral mucosa were collected. The expressions of Akt/mTOR/p70 S6K in these cases were detected using the SP method of immunohisto-chemistry. The correlation between their expressions in OSCC was also analyzed. Results The positive expressions of p-Akt, p-mTOR, and p70 S6K in OSCC were significantly higher than those in normal oral mucosa and paracancerous mucosa. The expressions of p-Akt, p-mTOR, and p70 S6K in OSCC were not correlated with age, gender, and clinical stage; by comparison, these expressions were correlated with lymph node metastasis and pathological grade. Strong positive correlations were also observed between the expressions of p-Akt, p-mTOR, and p70 S6K in OSCC. Conclusion Akt/mTOR/p70 S6K signaling molecules exhibit active expressions in OSCC and may be implicated in the occurrence and development of OSCC.

Aim To observe the effects of pituitrin ad- ministrated intravenously on electrocardiogram (ECG), and the effects of taurine on the ECG changes induced by pituitrin in conscious unrestrained rats. Methods ECG(leadⅡ)was recorded telemetrically and analyzed with Data Science International (DSI, USA); the changes of the ECG T wave and the heart rate at different times after the intravenous(iv) injection of pituitrin with or without intraperitoneal (ip) pre-administration of taurine were observed and calculated. Results ① Pituitrin 0.25～4.0 U?kg -1 dose-dependently elevated the ECG T wave; the T wave values were increased 0.75～3.42 times over the values before pituitrin, and the maximal effect appeared at 15 s after the injection. ② TAU 100, 200 or 400 mg?kg -1,injected intraperitoneally 30 min before the pituitrin, inhibited the T wave elevation and heart rate decrease induced by intravenous injection of pituitrin; compared with NS+pituitrin group, T wave elevation(mV) was decreased from 1.77?0.165 to 1.60?0.13(P