The ancient cardioprotective mechanisms of ACE2 bestow SARS-CoV-2 with a wide host range

SARS-CoV-2 infects a broader range of mammalian species than previously anticipated, suggesting there may be additional unknown hosts wherein the virus can evolve and potentially circumvent effective vaccines. We find that SARS-CoV-2 gains a wide host range by binding ACE2 sites essential for ACE2 carboxypeptidase activity. Six mutations found only in rodent species immune to SARS-CoV-2 are sufficient to abolish viral binding to human and dog ACE2. This is achieved through context-dependent mutational effects (intramolecular epistasis) conserved despite ACE2 sequence divergence between species. Across mammals, this epistasis generates sequence-function diversity, but through structures all bound by SARS-CoV-2. Mutational trajectories to the mouse conformation not bound by SARS-CoV-2 are blocked, by single mutations functionally deleterious in isolation, but compensatory in combination, explaining why human polymorphisms at these sites are virtually non-existent. Closed to humans, this path was opened to rodents via permissive cardiovascular phenotypes and ancient increases to ACE2 activity, serendipitously granting SARS-CoV-2 immunity. This reveals how ancient evolutionary trajectories are linked with unprecedented phenotypes such as COVID-19 and suggests extreme caution should be taken to monitor and prevent emerging animal reservoirs of SARS-CoV-2. One sentence summaryA conserved mechanism essential for ACE2 catalytic activity is exploited by SARS-CoV-2 binding, allowing the virus to infect a wide range of species.

ACE2 and TMPRSS2 are expressed on the human ocular surface, suggesting susceptibility to SARS-CoV-2 infection

Purpose Conjunctival signs and symptoms are observed in a subset of patients with COVID-19, and SARS-CoV-2 has been detected in tears, raising concerns regarding the eye both as a portal of entry and carrier of the virus. The purpose of this study was to determine whether ocular surface cells possess the key factors required for cellular susceptibility to SARS-CoV-2 entry/infection.Methods We analyzed human post-mortem eyes as well as surgical specimens for the expression of ACE2 (the receptor for SARS-CoV-2) and TMPRSS2, a cell surface-associated protease that facilitates viral entry following binding of the viral spike protein to ACE2.Results Across all eye specimens, immunohistochemical analysis revealed expression of ACE2 in the conjunctiva, limbus, and cornea, with especially prominent staining in the superficial conjunctival and corneal epithelial surface. Surgical conjunctival specimens also showed expression of ACE2 in the conjunctival epithelium, especially prominent in the superficial epithelium, as well as the substantia propria. All eye and conjunctival specimens also expressed TMPRSS2. Finally, western blot analysis of protein lysates from human corneal epithelium obtained during refractive surgery confirmed expression of ACE2 and TMPRSS2.Conclusions Together, these results indicate that ocular surface cells including conjunctiva are susceptible to infection by SARS-CoV-2, and could therefore serve as a portal of entry as well as a reservoir for person-to-person transmission of this virus. This highlights the importance of safety practices including face masks and ocular contact precautions in preventing the spread of COVID-19 disease.Competing Interest StatementThe authors have declared no competing interest.View Full Text

FEP-based screening prompts drug repositioning against COVID-19

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global crisis. There is no therapeutic treatment specific for COVID-19. It is highly desirable to identify potential antiviral agents against SARS-CoV-2 from existing drugs available for other diseases and, thus, repurpose them for treatment of COVID-19. In general, a drug repurposing effort for treatment of a new disease, such as COVID-19, usually starts from a virtual screening of existing drugs, followed by experimental validation, but the actual hit rate is generally rather low with traditional computational methods. Here we report a new virtual screening approach with accelerated free energy perturbation-based absolute binding free energy (FEP-ABFE) predictions and its use in identifying drugs targeting SARS-CoV-2 main protease (Mpro). The accurate FEP-ABFE predictions were based on the use of a new restraint energy distribution (RED) function designed to accelerate the FEP-ABFE calculations and make the practical FEP-ABFE-based virtual screening of the existing drug library possible for the first time. As a result, out of twenty-five drugs predicted, fifteen were confirmed as potent inhibitors of SARS-CoV-2 Mpro. The most potent one is dipyridamole (Ki=0.04 M) which has showed promising therapeutic effects in subsequently conducted clinical studies for treatment of patients with COVID-19. Additionally, hydroxychloroquine (Ki=0.36 M) and chloroquine (Ki=0.56 M) were also found to potently inhibit SARS-CoV-2 Mpro for the first time. We anticipate that the FEP-ABFE prediction-based virtual screening approach will be useful in many other drug repurposing or discovery efforts. Significance StatementDrug repurposing effort for treatment of a new disease, such as COVID-19, usually starts from a virtual screening of existing drugs, followed by experimental validation, but the actual hit rate is generally rather low with traditional computational methods. It has been demonstrated that a new virtual screening approach with accelerated free energy perturbation-based absolute binding free energy (FEP-ABFE) predictions can reach an unprecedently high hit rate, leading to successful identification of 16 potent inhibitors of SARS-CoV-2 main protease (Mpro) from computationally selected 25 drugs under a threshold of Ki = 4 M. The outcomes of this study are valuable for not only drug repurposing to treat COVID-19, but also demonstrating the promising potential of the FEP-ABFE prediction-based virtual screening approach.

Application of the superior thyroid artery peak systolic velocity in differentiating Graves′ disease from autoimmune thyroiditis / 中华内科杂志

Objective@#To evaluate the clinical value of the superior thyroid artery peak systolic velocity (STA-PSV) for the differential diagnosis of autoimmune thyrotoxicosis.@*Methods@#A total of 301 patients with newly diagnosed thyrotoxicosis and without any anti-thyroid drug intervention were collected from the Department of Endocrinology and Metabolism, Peking University People′s Hospital from Jan. 2015 to Oct. 2018. Among them, 241 patients were with Graves′ disease (GD) and 60 patients were with autoimmune thyroiditis (AIT). STA-PSV, thyroid function and thyrotropin receptor antibody (TRAb) were determined. A multiple linear regression was used to identify factors associated with STA-PSV. A receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to evaluate the discriminating ability of STA-PSV to GD.@*Results@#STA-PSV leves in GD group were significantly higher than those in AIT group [61.00 (41.00, 86.50) cm/s vs. 34.50 (25.25, 46.00) cm/s, P<0.001]. The ROC curve analysis showed that the AUC was 0.790 (95%CI 0.734-0.845), and 49.5cm/s was the optimal cutoff point for the diagnosis of GD, in which the sensitivity was 64.3% and the specificity was 83.3%. In all patients with thyrotoxicosis, multiple linear regression analyses showed free thyroxine (FT4) (β=0.371, 95%CI 0.005-0.010, P<0.001) and TRAb (β=0.138, 95%CI 0.001-0.014, P=0.035) were positively associated with STA-PSV.@*Conclusions@#The STA-PSV is positively associated with FT4 and TRAb levels, and it is a helpful marker in differential diagnosis between GD and AIT.

Application of the superior thyroid artery peak systolic velocity in differentiating Graves′ disease from autoimmune thyroiditis / 中华内科杂志

Objective:To evaluate the clinical value of the superior thyroid artery peak systolic velocity (STA-PSV) for the differential diagnosis of autoimmune thyrotoxicosis.Methods:A total of 301 patients with newly diagnosed thyrotoxicosis and without any anti-thyroid drug intervention were collected from the Department of Endocrinology and Metabolism, Peking University People′s Hospital from Jan. 2015 to Oct. 2018. Among them, 241 patients were with Graves′ disease (GD) and 60 patients were with autoimmune thyroiditis (AIT). STA-PSV, thyroid function and thyrotropin receptor antibody (TRAb) were determined. A multiple linear regression was used to identify factors associated with STA-PSV. A receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to evaluate the discriminating ability of STA-PSV to GD.Results:STA-PSV leves in GD group were significantly higher than those in AIT group [61.00 (41.00, 86.50) cm/s vs. 34.50 (25.25, 46.00) cm/s, P<0.001]. The ROC curve analysis showed that the AUC was 0.790 (95 %CI 0.734-0.845), and 49.5cm/s was the optimal cutoff point for the diagnosis of GD, in which the sensitivity was 64.3% and the specificity was 83.3%. In all patients with thyrotoxicosis, multiple linear regression analyses showed free thyroxine (FT 4) (β=0.371, 95 %CI 0.005-0.010, P<0.001) and TRAb (β=0.138, 95 %CI 0.001-0.014, P=0.035) were positively associated with STA-PSV. Conclusions:The STA-PSV is positively associated with FT 4 and TRAb levels, and it is a helpful marker in differential diagnosis between GD and AIT.

Effect of pituitrin-water separation in laparoscopic removal of ovarian chocolate cyst and its effect on ovarian function / 中国基层医药

Objective@#To investigate the effect of pituitrin-water separation on hemoglobin and ovarian function in laparoscopic ovarian chocolate cyst removal.@*Methods@#From February 2018 to February 2019, 82 patients with ovarian chocolate cyst removed by laparoscopy were selected from the Second Affiliated Hospital of Wenzhou Medical University.They were randomly divided into observation group and control group according to the digital table, with 41 cases in each group.The control group underwent traditional laparoscopic tear-and-tear ovarian cyst removal, while the observation group underwent pituitrin-water separation.The changes of perioperative indicators, the decrease of hemoglobin (Hb) before and after operation, the positive rate of normal ovarian tissue on cyst wall and the number of normal follicles attached to cyst wall, the changes of serum hormone levels before and after operation were compared between the two groups.@*Results@#The amount of bleeding during operation in the observation group [(58.97±8.74)mL] was less than that in the control group [(118.93±24.21)mL], and the operation time in the observation group[(57.46±8.27)min] was shorter than that in the control group [(87.38±10.19)min] , the differences were ststistically significant between the two group(t=14.916, 14.598, all P<0.05). There was no statistically significant difference in the time of anal exhaust between the two groups (P>0.05). The decrease of Hb in the observation group [(0.71±0.16)g/L] was lower than that in the control group [(1.27±0.35)g/L] (t=9.318, P<0.05). The positive rate of normal ovarian tissue on cyst wall in the observation group (21.95%) was lower than that in the control group (56.10%), the number of normal follicles attached to the cyst wall in the observation group (2.65±0.49) was less than that in the control group (4.86±1.24) , the differences were ststistically significant between the two group(χ2=10.045, t=10.613, all P<0.05). The serum level of E2 [(398.21±17.84)pmol/L] in the observation group was higher than that in the control group [(367.83±15.21)pmol/L], while FSH [(6.72±0.28)mIU/mL] and LH [(5.23±0.38)mIU/mL] levels in the observation group were lower than those in the control group [(7.19±0.35)mIU/mL and (5.69±0.31)mIU/mL], the differences were ststistically significant between the two group (t=8.298, 6.714, 6.006, all P<0.05).@*Conclusion@#The method of pituitrin-water separation is effective in laparoscopic ovarian chocolate cyst removal, which can reduce the injury during operation, has little effect on hemoglobin and improve the ovarian reserve function of patients.

A case of ectopic adrenocorticotropic hormone syndrome caused by paraganglioma mimic dermatomyositis / 中华风湿病学杂志

Objective@#To improve the recognition of ectopic adrenocorticotropic hormone syndrome.@*Methods@#The diagnosis and treatment of a 43 years old female patient with multiorgan involvement mimic dermatomyositis was analyzed and discussed.@*Results@#The patient presented with fatigue, edema, skin pigmentation, neuropsychiatric abnormalities, hypertension, hypokalemia, hyperglycemia and other systemic involvement, was finally diagnosed with ectopic adrenocorticotropic hormone syndrome caused by paraganglioma of the anterior mediastinum. After surgical removal of the tumor, her clinical symptoms immediately relieved, meanwhile related hormone levels returned to normal.@*Conclusion@#Although paraganglioma-induced ectopic adrenocorticotropic hormone syndrome is rare in clinical practice, more attention should be paid to this specific situation.

A case of ectopic adrenocor ticotropic hormone syndrome caused by paraganglioma mimic dermatomyositis / 中华风湿病学杂志

Objective To improve the recognition of ectopic adrenocorticotropic hormone syndrome.Methods The diagnosis and treatment of a 43 years old female patient with multiorgan involvement mimic dermatomyositis was analyzed and discussed.Results The patient presented with fatigue,edema,skin pigmentation,neuropsychiatric abnormalities,hypertension,hypokalemia,hyperglycemia and other systemic involvement,was finally diagnosed with ectopic adrenocorticotropic hormone syndrome caused by paragang-lioma of the anterior mediastinum.After surgical removal of the tumor,her clinical symptoms immediately relieved,meanwhile related hormone levels returned to normal.Conclusion Although paraganglioma-induced ectopic adrenocorticotropic hormone syndrome is rare in clinical practice,more attention should be paid to this specific situation.

Effect of pituitrin-water separation in laparoscopic removal of ovarian chocolate cyst and its effect on ovarian function / 中国基层医药

Objective To investigate the effect of pituitrin-water separation on hemoglobin and ovarian func-tion in laparoscopic ovarian chocolate cyst removal.Methods From February 2018 to February 2019,82 patients with ovarian chocolate cyst removed by laparoscopy were selected from the Second Affiliated Hospital of Wenzhou Medical University.They were randomly divided into observation group and control group according to the digital table,with 41 cases in each group.The control group underwent traditional laparoscopic tear-and-tear ovarian cyst removal,while the observation group underwent pituitrin-water separation.The changes of perioperative indicators ,the decrease of hemoglobin (Hb) before and after operation ,the positive rate of normal ovarian tissue on cyst wall and the number of normal follicles attached to cyst wall ,the changes of serum hormone levels before and after operation were compared between the two groups.Results The amount of bleeding during operation in the observation group [(58.97 ±8.74)mL] was less than that in the control group [(118.93 ±24.21)mL],and the operation time in the observation group[(57.46 ±8.27) min] was shorter than that in the control group [(87.38 ±10.19) min] ,the differences were ststistically significant between the two group ( t ＝14.916,14.598,all P ＜0.05 ).There was no statistically significant difference in the time of anal exhaust between the two groups (P＞0.05).The decrease of Hb in the observation group [(0.71 ±0.16)g／L] was lower than that in the control group [(1.27 ±0.35) g／L] ( t＝9.318,P＜0.05).The positive rate of normal ovarian tissue on cyst wall in the observation group (21.95%) was lower than that in the control group (56.10%),the number of normal follicles attached to the cyst wall in the obser-vation group (2.65 ±0.49) was less than that in the control group (4.86 ±1.24) ,the differences were ststistically significant between the two group ( χ2 ＝10.045, t ＝10.613, all P ＜0.05).The serum level of E2 [( 398.21 ± 17.84)pmol／L] in the observation group was higher than that in the control group [(367.83 ±15.21) pmol／L], while FSH [(6.72 ±0.28)mIU／mL] and LH [(5.23 ±0.38)mIU／mL] levels in the observation group were lower than those in the control group [(7.19 ±0.35)mIU／mL and (5.69 ±0.31)mIU／mL],the differences were ststisti-cally significant between the two group (t＝8.298,6.714,6.006,all P＜0.05).Conclusion The method of pitui-trin-water separation is effective in laparoscopic ovarian chocolate cyst removal ,which can reduce the injury during operation,has little effect on hemoglobin and improve the ovarian reserve function of patients .

A Preliminary Study on the Safety of Anterolateral Approach Elbow Arthroscopy / 中国微创外科杂志

Objective To evaluate the anatomic relationships between the portals and radial nerve of three different operations of antrolateral approach elbow arthroscopy.Methods The dissections were pedormed in 10 formalin soaked adult cadaver elbows.The distances from the three different antrolateral portals to the radial nerve in extension and flexion 90° position were measured.The portal A was located at 3 cm distal and 1 cm anterior to the lateral epicondyle;the portal B was located at 2 cm distal and 2 cm anterior to the lateral epicondyle;the portal C,1 cm distal and 1 cm anterior to the lateral epicondyle.Results The nearest distances from the anterolateral portal A,B,and C to the radial nerve in extension position were (2.30 ± 0.95) mm,(3.00 ± 1.56) mm,and (3.60 ± 1.65) mm,with significant differences (F =11.097,P =0.001).Statistical difference in distances from the anterolateral portal to the radial nerve between portal A and C was found (P =0.006).No statistically significant difference was seen between A and B or B and C (PA-B =0.134,PB-c =0.072).The distances from the anterolateral portal A,B,and C to the radial nerve in flexion 90° position were (4.40 ± 2.01) mm,(6.10 ± 1.79) mm,and (7.90 ± 1.85) mm,with significant differences (F =54.775,P =0.000).There were statistically significant difference among the three approaches (PA-B =0.000,PA-c =0.000,PB-c =0.002).The distances increased when the position changed from extension to flexion 90° for portal A (t =-5.161,P =0.001),portal B (t=-8.188,P=0.000),and portal C (t =-10.167,P =0.000).Conclusion The anterolateral portal 1 cm distal and 1 cm anterior to the lateral epicondyle is the safest apporach.

Analgestic Effect of Scalp Nerve Block with Ropivacaine Hydrochloride at Different Time Points After Craniotomy / 医药导报

Objective To observe the effect of scalp nerve block ( SNB ) with ropivacaine hydrochloride at different time points on pain management after craniotomy. Methods Ninety patients undergoing craniotomy were randomly divided into 3 groups:group A, SNB conducted before surgery;group B, SNB conducted after surgery;group C, SNB conducted both before and after surgery, with 0. 5% of ropivacaine hydrochloride in each group. All patients received the same general anesthesia and diclofenac sodium were administered rectally as rescue analgesics. Sites and duration of surgeries, end-tidal sevoflurane concentration during incision, HR and SBP levels during the course of surgery and postoperative period, the VAS scores, GCS and Ramsay scores at 0. 5, 2, 4, 6, 12, 24, 48 h postoperatively, time of the first rescue appication analgesics and total consumption of rescue analgesics, the adverse effects, awareness under anesthesia were analyzed respectively, as well as local anesthesia relevant adverse events and time of wound healing. Results The end-tidal sevoflurane concentration was significantly decreased in group B (3. 19±0. 36)% as compared with group A (1. 81±0. 24)% and C (1. 77±0. 33)% (P0. 05);Compared with group A (600 mg), the consumption of rescue analgesics of group B (300 mg) and C (250 mg) were statistically lower (P0. 05);The relevant side effects were not different statistically, and there were no patients suffering from obvious awareness under anesthesia, pruritus, respiratory depression or local anesthesia relevant adverse effects. Conclusion SNB conducted before surgery can decrease the consumption of sevoflurane during incision, but has limited analgesic effects postoperatively. SNB conducted after surgery may provide transitional analgesia for neurosurgical patients undergoing craniotomy, while SNB conducted both before and after surgery does not show significantly longer analgesic time in postoperative pain management.

A meta-analysis of stroke risk in type 2 diabetic patients treated with sulfonylurea / 中华内分泌代谢杂志

Objective To investigate whether sulfonylurea ( SU) increases the risk of stroke in patients with type 2 diabetes mellitus(T2DM). Methods A systemic meta-analysis including 17 random control trails(RCT) was performed to compare the risk of stroke between type 2 diabetic patients treated with SUs and comparators. Results 1 612 articles were retrieved, and finally 17 articles were included. Patients receiving SUs treatment had a higher relative risk of stroke (RR 1. 35, 95% CI 1. 13-1. 60) than those who received comparators. The I2 statistic for heterogeneity between 17 trails was 0. 0%(P=0. 687). No major asymmetry appeared in the funnel plot and Begg′adjusted rank correlation test(kendall′s score=22, P=0. 387). Conclusion The use of SUs may raise the risk of stroke which is already high in patients with T2DM.

Effects of RNA interference of FABP5 on subcutaneous tumor of human hepatocellular carcinoma cell line HepG2 transplanted in nude mice / 中国病理生理杂志

AIM:To investigate the effect of recombinant lentiviral vector for RNA interference (RNAi) on the expression of fatty acid-binding protein 5 (FABP5) gene in hepatocellular carcinoma HepG2 cells and tumor formation in nude mice.METHODS:RNAi lentiviral vector was used in the experiment.Human hepatocellular carcinoma HepG2 cells were divided into 3 groups:the HepG2 cells in experimental group were transfected with the recombinant lentivirirus vector LV-shRNA-FABP5, the cells in negative control group were transfected with a control lentiviral vector LV-shRNA-NC, and the cells in normal control group were without any treatment.The nude mice were randomly divided into 3 groups.The growth of the transplanted tumor cells in the nude mice was observed.The tumor growth curve, volume and weight were de-termined 4 weeks after the cell inoculation.The expression of FABP5 was detected by real-time PCR, Western blot and im-munohistochemical staining.RESULTS:Transfection of the lentiviral vector FABP5-shRNA obviously reduced FABP5 ex-pression in the HepG2 cells.Tumor formation was all positive in the 3 groups of the nude mice inoculated with the tumor cells.Compared with normal control group and negative control group, the tumor growth slowed significantly in experimental group with smaller volume and weight.FABP5 expression in the transplanted tumor tissues was significantly down-regulated at mRNA and protein levels in experimental group as compared with normal control group and negative control group. CONCLUSION:RNAi-induced down-regulation of FABP5 effectively inhibits the growth of transplanted hepatocellular carcinoma, suggesting that FABP5 gene may be an effective target for gene therapy in treating liver cancer.

Effects of RNA interference targeting CDC25a gene on proliferation of human liver cancer HepG2 cells / 中国病理生理杂志

[ ABSTRACT] AIM:To investigate the effect of silencing cell division cycle 25a ( CDC25a) gene on the prolifera-tion of human hepatoma HepG2 cells.METHODS:CDC25a gene in human hepatoma HepG2 cells was silenced by RNA interference.Real-time PCR was applied to detect the expression of CDC25a, cyclin E and CDK2 at mRNA levels in the HepG2 cells.Western blotting was applied to detect the expression of CDC25a at protein level.In addition, MTT assay, Giemsa staining and flow cytometry were used to measure the proliferation of human hepatoma HepG2 cells.RESULTS:The expression of CDC25a at mRNA and protein levels in RNA silence group was lower than those in negative control group and normal control group (P<0.05).The mRNA expression of cyclin E and CDK2 in silence group was lower than that in negative control group and normal control group (P<0.05).The cell proliferation in silence group was lower than that in negative control group and normal control group ( P<0.05) .The results of flow cytometry revealed that the cells in silence group were blocked in G1 phase.CONCLUSION:Infection of LV-CDC25a-RNAi recombinant to the HepG2 cells effec-tively inhibits the CDC25a gene expression and the proliferation of human hepatoma cells, and arrests the cells in G1 phase, suggesting that CDC25a gene may be a key target for the treatment of liver cancer.

Preparation and antibacterial capacity of artificial skin loaded with nanoparticles silver using bacterial cellulose / 生物医学工程学杂志

In the present paper, in-situ preparation of silver nanoparticles have been conducted in 3D network structure of BC membrane through liquid phase chemical deoxidization method. The characterization of products was investigated using scanning electron microscopy (SEM), infrared spectroscopy (IR), energy dispersion spectrometry (SEM-EDS). The absorbing water capacity and preserving water capacity of substitutes and the antibacterial capacities of antibacterial agent-loaded artificial skin were tested. The results showed the silver nanoparticles were approximately spherical particles with an average diameter of 45nm, and were noted to have excellent sterilizing efficacy the efficiency of against Escherichia coli, yeast and Candida albicans.