OBJECTIVE To investigate the regulatory effects of couplet medicinals of Atractylodes macrocephala-Aucklandia lappa on gut microbiota and short-chain fatty acids （SCFAs） in the diarrhea-type irritable bowel syndrome （IBS-D） rats with spleen deficiency. METHODS The IBS-D rat model with spleen deficiency was induced by intragastric administration of Senna alexandrina combined with restraint stimulation. The model rats were divided into model group， positive control group （pinaverium bromide 1.5 mg/kg）， A. macrocephala-A. lappa low-dose， medium-dose and high-dose groups （0.7， 1.4， 2.8 g/kg）， with 6 rats in each group. Another 6 healthy rats were taken as the blank control group. The blank control group and the model group were given normal saline intragastrically， and other groups were given relevant drug liquid intragastrically， once a day， for consecutive 14 days. The general characteristics of rats and fecal water content were observed， and intestinal sensitivity [evaluating by abdominal wall withdrawal reflex （AWR） threshold] and the intestinal propulsion rate were determined. The serum levels of 5- hydroxytryptamine（5-HT）and SP were detected， and the pathological changes of colon tissue were observed； the protein expressions of 5-HT-3 receptor（5-HT3R）， 5-HT4R and 5-HT transporter（SERT） in colon tissue of rats were detected. 16S rRNA sequencing was performed for the feces of rats in blank control group， model group and A. macrocephala-A. lappa high-dose group； the contents of acetic acid， propionic acid and butyric acid in the feces of the rats were determined. RESULTS Compared with the model group， the body weight after 7 and 14 days of medication， fecal water content， AWR threshold， and the protein expressions of 5-HT4R and SERT in colon tissue were increased significantly in the A. macrocephala-A. lappa medium-dose and high-dose groups （P＜0.05 or P＜0.01）； serum contents of 5-HT and SP， intestinal propulsion rate （except for A. macrocephala-A. lappa medium-dose group）， the protein expression of 5-HT3R in colon tissue were decreased significantly （P＜0.01）； diarrhea relief， mental state recovery， and partially recovery of the structure of colon tissue were all found； moreover， the diversity and species number of gut microbiota were reduced in A. macrocephala-A. lappa high-dose group and the content of butyric acid in fecal samples was significantly reduced （P＜0.05）. CONCLUSIONS The compatibility of A. macrocephala and A. lappa can improve intestinal motility and sensitivity of IBS-D model rats with spleen deficiency， and alleviate diarrhea. This may be related to improving changes in intestinal microbiota structure， reducing 5-HT expression and butyric acid content， and increasing 5-HT4R and SERT expression.

Video-based intelligent action recognition remains challenging in the field of computer vision.The review analyzes the state-of-the-art methods of video-based intelligent action recognition,including machine learning methods with handcrafted features,deep learning methods with automatically extracted features,and multi-information fusion methods.In addition,the important medical applications and limitations of these technologies in the past decade are introduced,and the interdisciplinary views on the future application to improve human health are also shared.

Objective:To characterize the biomechanics of distal dynamic locking and distal static locking of proximal femur bionic nails (PFBN) in fixation of intertrochanteric fractures by a finite element analysis.Methods:The CT image data from the hip to the upper tibia from an adult male volunteer were used to establish a three-dimensional model of the femur by Mimics 20.0 and Geomagic 2013 which was processed further into a model of Evans type I intertrochanteric fracture by software NX 12.0. With reference to the internal fixation parameters commonly used, 4 models of PFBN fixation were established: distal single transverse nail dynamic locking (model A), single oblique nail dynamic locking (model B), single nail static locking (model C) and double nail dynamic locking (model D). Abaqus 6.14 software was used to load and analyze the internal fixation stresses and displacements of fracture ends.Results:Under a 2100N loading, the peak stress was located upon the main nail in the 4 models. The smallest peak stress upon the main nail was in Model D (161.9 MPa), decreased by 15.9% compared with model A (192.5 MPa), by 15.6% compared with model B (191.9 MPa), and by 0.9% compared with model C (163.3 MPa). The peak stress upon the fixation screw was the largest in model A (95.3 MPa), the smallest in model B (91.5 MPa), and 91.5 MPa and 92.2 MPa in models C and D, respectively. The overall displacements of the implants, in a descending order, were 10.14 mm in model A, 10.10 mm in model B, 10.09 mm in model C, and 10.05 mm in model D. Similarly, the displacements of fracture ends were 0.125 mm in model A, 0.121 mm in model B, 0.110 mm in model C, and 0.098 mm in model D.Conclusion:Compared with dynamic locking, distal static locking of PFBN provides a better mechanical stability and reduces stress concentration upon internal fixation.

Objective To establish and evaluate a rapid detection method for SARS-CoV-2 based on reverse transcriptase-recombinase aided amplification(RT-RAA)combined with the clustered regularly interspaced short palindromic repeats(CRISPR)/Cas12a system.Methods RT-RAA primers and CRISPR-derived RNA(crRNA)were designed based on the nucleocapsid(N)gene of SARS-CoV-2 from NCBI database.The detection system was optimized with magnesium acetate(MgAc)concentration,RT-RAA reaction tempera-ture and time and LbCas12a reaction temperature.The sensitivity and specificity of the method were evaluated using recombinant plas-mids(100-106 copies/μL)and other respiratory pathogens.The RT-RAA-CRISPR/Cas12a method was compared with RT-PCR by tes-ting 70 clinical samples in parallel.Results The optimized RT-RAA-CRISPR/Cas12a assay could detect SARS-CoV-2 within 50 min at 37 ℃.The limit of detection was 10 copies/μL for the fluorescence-based method and 1×102 copies/μL for the lateral flow assay.The method specifically detected SARS-CoV-2 without cross-reactivity to other respiratory pathogens.The results of testing 70 clinical samples using RT-RAA-CRISPR/Cas12a showed agreement of 100％with those of RT-PCR.Conclusion The established RT-RAA-CRISPR/Cas12a assay for SARS-CoV-2 detection is rapid,cost-effective,highly sensitive and specific.It can be performed by less experienced personnel and no expensive equipment is required,thus it may provide a new approach for rapid clinical diagnosis and large-scale on-site screening of SARS-CoV-2.

Pain is a defensive response to body injury or potential injury, and is also the most common clinical manifestations in orthopedic trauma. Pain is critical to determine the causes of injury and therapeutic plans in the diagnosis and treatment of orthopedic trauma. Post-traumatic acute and chronic pain not only brings physical pain to patients, but also induces a variety of complications. Moreover, improper evaluation and management of pain can easily lead to missed diagnosis and misdiagnosis, thus prolonging the treatment cycle and affecting the quality of life. At present, the management of pain has no normative standard in the diagnosis and management of orthopedic trauma. Academician Zhang Yingze′s team has summarized the pain characteristics of various orthopedic trauma patients, traced back to the sources, and conduced the innovative concept of "pain" to get the melon to address issues such as insufficient pain assessment, incomplete etiology analysis and inadequate diagnostic thinking, hoping to achieve rapid and accurate diagnosis and early treatment. The authors elaborate on the connotation of the innovative concept of "pain" to get the melon and its application in clinical orthopedic trauma, aiming to explore the application value of this innovative concept, achieve rapid and accurate diagnosis of orthopedic trauma and provide a reference for formulating reasonable diagnosis and treatment programs.

Due to the failure of multiple translational researches, Stroke Therapy Academic Industry Roundtable (STAIR) recommends the use of large animal models of focal cerebral ischemia for preclinical researches. Especially, stroke treatment has currently entered a new era of vascular recanalization. Large animals commonly used in acute ischemic stroke models include dogs, swine, sheep, and non-human primates, which can be used to simulate various aspects of cerebral ischemia and reperfusion (vascular recanalization) in patients. Although large animals have significant advantages due to their proximity to humans in anatomy and physiology, there are also issues with anatomical and physiological specificity and ethical limitations. This article summarizes the large animal ischemic stroke models prepared by craniotomy and endovascular intervention, hoping to help researchers select the most appropriate large animal ischemic stroke model, and then promote the development of stroke translational research.

Because the clinical studies of neuroprotective drugs ended in failure, the Stroke Treatment Academy Industry Roundtable recommended the use of non-human primates for preclinical research on stroke. Non-human primates are the bridge between basic experiment and clinical research, and the experimental results are of great reference value. However, non-human primate stroke models have a variety of neurological deficits and behavioral evaluation methods, and the scoring methods also have their own emphases. It is easy to have differences in the evaluation, or there are deficiencies in the scale itself, resulting in inaccurate scoring, which directly affects the experimental results and the implementation of subsequent research. This article summarizes the neurological deficits and behavioral evaluation methods of non-human primate stroke model.

Objective:To synthesize 177Lu-prostate-specific membrane antigen (PSMA)-617 with domestic 177Lu (made in China), and explore its optimal labeling condition, biodistribution, stability, and safety. Methods:177Lu-PSMA-617 was prepared with domestic 177Lu by a manual method. The optimal labeling condition, radiochemical purity, stability ( in vivo and in vitro), lipid-water partition coefficient, and plasma protein binding rate were determined. The uptake rate of 177Lu-PSMA-617 was evaluated by using 22RV1 cells. Biodistribution and SPECT/CT imaging were performed on normal mice with imported 177Lu-PSMA-617 as control group. The blood routine test was performed to evaluate the safety. Results:The best labeling result of domestic 177Lu-PSMA-617 can be obtained under the following conditions: pH=4.5, 100 ℃ for 30 min. And the radiochemical purity was ≥99%. The product was stable in vivo and in vitro, with the radiochemical purity >95% in 72 h. The plasma protein binding rate was (35.3±5.3)%, the lipid-water partition coefficient was -2.27±0.06, and the specific uptake rate of domestic 177Lu-PSMA-617 by 22RV1 cells reached the highest in 1 h ((7.58±0.84)%), which was slightly lower than the imported 177Lu-PSMA-617 ((7.86±0.96)%), but there was no significant difference between them ( t=-0.439, P>0.05). The distribution and SPECT/CT imaging of normal mice showed that domestic and imported 177Lu-PSMA-617 in blood were cleared quite fast, and both of them were excreted mainly through the kidneys. No obvious adverse reactions were found in the toxicity test of domestic and imported 177Lu-PSMA-617. There was no obvious abnormality in blood routine and liver and kidney metabolism. Conclusion:The domestic 177Lu-PSMA-617 has many advantages, such as qualified quality control, good biological properties and safety, which support its potential application value in diagnosis of prostatic neoplasms.

A retrospective analysis was performed on the clinical data of a child with X-linked hyper IgM syndrome (XHIGM) with cholangiectasis as a major manifestation in Children′s Hospital of Fudan University in March 2017.The patient was a 4-year-old boy who was admitted to the hospital due to repeated diarrhea for half a year and yellow skin for 5 days.No abnormalities were found in his fetal period and birth history; The patient had 2 severe pneumonias and suppurative infection of the left axillary lymph node in infancy.Physical examination revealed delayed physical development, severe malnutrition, moderately stained yellow, lymphadenopathy and hepatomegaly.Laboratory examinations showed elevated leukocyte, eosinophils and C-reactive protein, low hemoglobin and albumin, high gamma-glutamyl transpeptidase (GGT), low IgG and normal IgM.Imaging examination revealed diffuse expansion of intrahepatic and extrahepatic bile ducts.Hepatic pathology showed hyperplasia in the bile canaliculus and some fibrous tissues around the large bile ducts.High-throughput sequencing identified a pathogenic mutation in the XHIGM gene CD 40LG (exon5 c. 506A>G, p.Y169C), with his mother as a carrier.After admission, the patient was given anti-infection, diet adjustment, albumin, intravenous immunoglobulin and ursodeoxycholic acid.The patient was discharged after the improvement in his condition.This case suggested that in addition to the common infection characteristics, XHIGM can also be manifested as diffuse intrahepatic, extrahepatic cholangiectasis and significantly elevated eosinophil.c.506A>G mutation in CD 40LG was the pathogenic mutation of this disease.

Objective    To investigate the characteristics and prognostic value of cellular immune function in severe patients with coronavirus disease 2019 (COVID-19). Methods    A cohort study was conducted to collect the clinical data of 119 severe patients admitted to the Renmin Hospital of Wuhan University (Eastern District) including 60 males (50.4%) and 59 females (49.6%), with an average age of 60.9±14.2 years. The primary endpoint of follow-up was death in the hospital, and the disease outcome classification was the secondary endpoint of follow-up within 30 days after admission. We analyzed the correlation between cellular immune function and COVID-19 prognosis. Results     A total of 22 patients died during this process, and 47 patients were severe/critical during the follow-up period. The counts of CD3+, CD4+, CD8+, and CD19+ in the primary endpoint events were significantly different between the survival group and the death group (all P<0.05). The counts of CD3+, CD4+, CD8+, CD19+ in the secondary endpoint events were significantly different between the normal group and the severe/critical group (all P<0.05). The results of the receiver operating characteristic (ROC) curve showed that the area under the cellular immune function curve of dead patients and severe/critical patients had good predictive value (all P<0.05). Conclusion    Cell immune function has good clinical and prognostic value for COVID-19.