Scaffold hopping refers to computer-aided screening for active compounds with different structures against the same receptor to enrich privileged scaffolds, which is a topic of high interest in organic and medicinal chemistry. However, most approaches cannot efficiently predict the potency level of candidates after scaffold hopping. Herein, we identified potent PDE5 inhibitors with a novel scaffold via a free energy perturbation (FEP)-guided scaffold-hopping strategy, and FEP shows great advantages to precisely predict the theoretical binding potencies ΔG _FEP between ligands and their target, which were more consistent with the experimental binding potencies ΔG _EXP (the mean absolute deviations | Δ G FEP - Δ G EXP |  < 2 kcal/mol) than those ΔG _MM-PBSA or ΔG _MM-GBSA predicted by the MM-PBSA or MM-GBSA method. Lead L12 had an IC₅₀ of 8.7 nmol/L and exhibited a different binding pattern in its crystal structure with PDE5 from the famous starting drug tadalafil. Our work provides the first report via the FEP-guided scaffold hopping strategy for potent inhibitor discovery with a novel scaffold, implying that it will have a variety of future applications in rational molecular design and drug discovery.

Cranial Nerves ; Humans ; Lymphoma ; Nervous System Malformations

Angiofibroma/surgery* ; Endoscopy ; Humans ; Nasopharyngeal Neoplasms/surgery* ; Retrospective Studies

Emergencies refer to those events that cause serious social harm, including natural disasters and public health events, and require emergency response. Medical rescue team is the main emergency rescue team. While carrying out the rescue mission, they are under great pressure both physically and mentally due to the unadaptability of the rescue environment, the lack of protective materials, overwork and other reasons, often resulting in fear, tension, anxiety, pessimism, self-blame and even acute stress disorder. Without timely and effective psychological support, long-term psychological problems such as post-traumatic stress disorder will remain after the event. Comprehensive psychological support includes psychological measurement of the whole rescue process, team formation before rescue and detailed psychological support intervention training, self-relaxation during rescue, basic life and safety guarantee, drug treatment, online psychological assistance, withdrawal of stressors after rescue and lifestyle reconstruction.

OBJECTIVE: To knockout ADRB2 gene rapidly and efficiently in human primary T cells by using CRISPR/Cas9 technology and multiple sgRNAs strategy. METHODS: Six paired-sgRNAs, which were designed to target the 5' constitutive coding exons of ADRB2 gene, were cloned into pGL3-U6-sgRNA-PGK-Puro vector separately. The expre-ssion vectors containing the single sgRNAs were constructed and transiently co-transfected into HEK-293T cell line with Cas9 expression vector. The sgRNA-mediated cleavage efficiency was tested by T7EN I digestion assay. Concatenating four highly efficient paired sgRNAs were cloned into pGL3-U6-sgRNA-ccdB-EF1α-Puro expression vector. The reco-mbinant plasmid allows the cells to express 4 sgRNAs, which target different sites on the ADRB2 genomic locus. The cleavage efficiency and mutation model were tested by T7EN I digest assay and T-A cloning technique. Multiple sgRNAs plasmid and Cas9 plasmid was transiently transferred into human primary T cells by electroporation. Flow cytometry (FCM) was used to detect the knockout efficiency of β2 adrenergic receptor (β2-AR). RESULTS: The results of T7EN I digestion and TA cloning sequencing showed that the multiple sgRNAs strategy could obtain more abundant mutation types and higher gene editing efficiency than single sgRNA. In addition to the deletion and insertion of bases, large fragment DNA deletions and inversions could be observed. All of the random 10 TA clones for detection were genetically modified, thus the mutation efficiency was as high as 100%. FCM assay showed that 43.09% of the cells in the control T cells were β2-AR positive, but the proportion of β2-AR positive cells in the multiple sgRNAs electrotransformed T cells decreased to 25.61%. CONCLUSION A method, which is simple and operable, for knocking out β2-AR in human primary T cells has been established preliminarily. The results are helpful for the further study of the role of β2-AR in human T cells.
CRISPR-Cas Systems ; Gene Editing ; Gene Knockout Techniques ; Humans ; RNA, Guide ; Receptors, Adrenergic, beta-2 ; genetics ; T-Lymphocytes

·AIM: To evaluate a deep learning - assisted diagnostic system with an artificial intelligence for the detection of diabetic retinopathy (DR). ·METHODS:A total of 186 patients (372 eyes) with diabetes were recruited from January to July 2017. Discrepancies between manual grades and artificial intelligence results were sent to a reading center for arbitration. The sensitivity and specificity in the detection of DR were determined by comparison with artificial intelligence diagnostic system and experts human grading. ·RESULTS:Based on manual grades, the results as follows:non DR (NDR) in 42 eyes (11.3%), 330 eyes (88.7%) in different stages of DR. Among 330 DR eyes, there were mild non proliferative DR (NPDR) in 62 eyes (16.7%), moderate NPDR in 55 eyes (14.8%), severe NPDR in 155 eyes (41.7%), and proliferative DR (PDR) in 58 eyes (15. 6%). Based on artificial intelligence diagnostic system, the results were as follows: NDR in 38 eyes (10.2%),PDR in 44 eyes (11.8%), others were NPDR. The sensitivity and specificity of artificial intelligence diagnostic system, compared with human expert grading, for the detection of any DR were 0.82 and 0.91, and the kappa value was 0.77 (x2=20.39, P<0.05). ·CONCLUSION:This study shows that a deep learning-assisted diagnostic system with an artificial intelligence for grading diabetic retinopathy is a reliable alternative to diabetic retinopathy assessment, thus the use of this system may be a valuable tool in evaluating the DR.

Background: Automated peritoneal dialysis (APD) can cater to individual needs, provide treatment while asleep, take into account the adequacy of dialysis, and improve the quality of life. Currently, independent research and development of APD machines made in China are more conducive to patients. A randomized, multicenter, crossover study was conducted by comparing an APD machine made in China with an imported machine. The safety, effectiveness, and manipulability of the two machines were compared. Methods: Two hundred and sixty patients who underwent peritoneal dialysis (PD) on a regular basis in 18 centers between August 2015 and February 2016 were included. The inclusion criteria include age ≥18 years and PD ≥30 days. The exclusion criteria were as follows: hemodialysis; exit site or tunnel infection; and peritonitis ≤30 days. The patients were randomly divided into Group A, who were first treated with a FM machine made in China, then changed to an imported machine; and Group B, who were treated using the reverse sequence. APD treatment was performed with 10 L/10 h and 5 cycles of exchange. After 72 h, the daily peritoneal Kt/V, the accuracy of the injection rate, accuracy of the injection temperature, safety, and manipulability of the machine were assessed. Noninferiority test was conducted between the two groups. Results: The daily peritoneal Kt/V in the APD machine made in China and the imported APD machine were 0.17 (0.14, 0.25) and 0.16 (0.13, 0.23), respectively. There was no significant difference between the groups (Z = 0.15, P = 0.703). The lower limit of the daily Kt/V difference between the two groups was 0.0069, which was greater than the noninferiority value of -0.07 in this study. The accuracy of the injection rate and injection temperature was 89.7% and 91.5%, respectively, in the domestic APD machine, which were both slightly better than the accuracy rates of 84.0% and 86.8% in the imported APD machine (89.7% vs. 84.0%, P = 0.2466; 91.5% vs. 86.8%, P = 0.0954). Therefore, the APD machine made in China was not inferior to the imported APD machine. The fuselage of the imported APD machine was space-saving, while the APD machine made in China was superior with respect to body mobility, man-machine dialog operation, alarm control, and patient information recognition. Conclusions: The FM machine made in China was not inferior to the imported APD machine. In addition, the FM machine made in China had better operability. Trial Registration Clinicaltrials.gov, NCT02525497; https://clinicaltrials.gov/ct2/results?cond=&term=NCT02525497&cntry=& state=&city=&dist=.
Adult ; China ; Cross-Over Studies ; Female ; Humans ; Male ; Middle Aged ; Multicenter Studies as Topic ; Peritoneal Dialysis ; adverse effects ; instrumentation ; methods ; Quality of Life ; Temperature

AIM To determine effective components of Ampelopsis grossedentata (Hand.-Mazz.) W.T.Wang under different breeding modes and to analyze the antioxidant enzyme activities.METHODS Single factor and orthogonal tests were adopted in screening the optimal extraction process of antioxidant enzymes and analyzing antioxidant enzyme activities of A.grossedentata under common cutting,two-phase cutting and tissue culture.Solvent extraction method was adopted in extracting the effective components of three breeding modes in stem leaves of A.grossedentata,whose contents were determined.RESULTS In three breeding modes,the content of polysaccharides in tissue culture seedling was the highest,while the contents of flavonoids and polyphenols in the two stage cutting seedlings were the highest.The optimal extraction process of antioxidant enzymes was determined to be 6.0 for pH,20 ℃ for processing temperature and 20 min for processing time.Antioxidant enzyme activities were in sequence of two stage cutting seedlings ＞ common cutting seedling ＞ tissue culture seedling.CONCLUSION Considering the contents of effective components and antioxidant enzyme activities,two stage cutting method is the best among 3 breeding modes.

Background:Functional dyspepsia (FD)with anxiety and gastric hypersensitivity is still one of the therapeutic difficulties in clinic. Gastrodin (Gas)may have dual effects of modulating gastric sensitivity and anxiety. Aims:To investigate the effect of Gas on gastric sensitivity and anxiety-like behavior in FD with anxiety-like gastric hypersensitivity in rats. Methods:Forty rats were randomly divided into control group,model group,buspirone group,low-dose Gas group and high-dose Gas group. Maternal separation,acute gastric irritation and restraint stress were sequentially performed to induce FD model with anxiety-like gastric hypersensitivity. At the 8th week,rats in control group and model group were intraperitoneally injected with 0. 9% NaCl solution 2. 0 mL/ kg,rats in buspirone group were given buspirone 3. 125 mg/kg,and rats in low- and high-dose Gas groups were given 62. 5,125. 0 mg/ kg Gas,respectively. The course was 7 days. Then elevated plus maze (EPM),open field test,abdominal withdrawal reflex (AWR)and electromyography (EMG) were performed. Results:Compared with control group,EPM test showed that proportions of open arms entries and duration were significantly decreased (P < 0. 01);open field test showed that virtual central grids duration (P < 0. 05),number of virtual grids climbed and times of lifting were significantly decreased (P < 0. 01);when gastric balloon dilatation pressure was equal or greater than 40 mm Hg,AWR score,area under ROC curve (AUC)of EMG was significantly increased in model group (P < 0. 05). Compared with model group,above-mentioned indices in low- and high-dose Gas groups were significantly ameliorated (P < 0. 05). Conclusions:Gas could influence the gastric sensitivity and anxiety-like behavior of the brain-stomach axis regulated anxiety-like gastric hypersensitivity in FD rat model.

Objective To establish an anxiety-like gastric hypersensitivity ( GHS) rat model of functional dyspep-sia induced by new sequential stress. Methods Twenty-six male 1-day-old Sprague-Dawley rat pups were randomly di-vided into control and model groups ( n=13 in each group) . The model rats received sequential stress from postnatal day 2:neonatal maternal separation (NMS), acute gastric irritation (AGI) and restraint stress (RS). The control rats were reared freely with their mothers without undergoing the sequential stress. From postnatal 8th week all rats started to receive elevated plus maze ( EPM ) , open field test ( OF ) , abdominal withdrawal reflex ( AWR ) and electromyographic test ( EMG) . Results EPM and OF experiments depicted that the model rats showed obvious anxiety-like behavior ( P<0. 05 or P<0. 01). AWR and EMG tests exhibited that the model rats had elevated gastric hypersensitivity to gastric distention (P<0. 05 or P<0. 01). Conclusions An anxiety-like GHS rat model of functional dyspepsia can be successfully estab-lished with our new method of sequential stress.