Comparison of pretreatment techniques for single-cell RNA sequencing of airway aspirate specimens / 中华微生物学和免疫学杂志

Objective:To investigate the appropriate pretreatment methods for single cell RNA sequencing of airway aspirate cells.Methods:Four fresh airway aspirate specimens were collected from four patients with acute respiratory tract infections. These specimens were digested with airway aspirate digester and prepared into single cell suspension. The cells were used for library construction directly (DE), or fixed with 10×Genomics Chromium Next GEM Single Cell Fixed RNA Sample Preparation Kit and then mixed to construct the library (DF), or cryopreserved, thawed, fixed (FF) before mixed to construct the library. All three methods were treated with oil emulsion using 10 4 cells and subjected to single-cell sequencing using the 10×Genomics platform. The number of obtained cells, data quality, annotated cell types and expression of marker genes were analyzed. Differences in the expression of highly variable genes (HVGs) of the same cell subsets obtained by the three pretreatment methods were compared using Pearson correlation. Expression of the differentially expressed genes in the same cell subpopulation obtained by different pretreatment methods was also compared. The correlation of the expression of differentially expressed genes between the same cell subsets obtained by the three pretreatment methods was analyzed by Pearson correlation. Results:The median numbers of single cells obtained using DE, FF and DF methods were 2 733, 1 140 and 5 897 ( P>0.05). The unique molecular identifiers were higher than 500. The median numbers of genes obtained using the three methods were 801, 887 and 1 259 ( P>0.05). The cells with novelty score over 0.8 accounted for 99%, 87% and 93%, respectively. There were nine cell subsets obtained by the three methods, including squamous cells, secretory cells, ciliated cells, T cells, B cells, macrophages, plasma cells and neutrophils. DF and FF methods could obtain more basal cells with specific high expression of keratin 5 than DE method. The differentially expressed and highly variable genes in the same cell subsets obtained by the three pretreatment methods showed high consistency in their expression with a significant correlation ( P<0.001). Conclusions:Under the same sequencing data volume, the quality of data obtained from fixed airway aspirate single-cell suspensions using the method of probe hybridization and transcriptome sequencing was comparable to that obtained directly from fresh cells. This method was more suitable for the pretreatment of clinical samples used for single-cell RNA sequencing.

A resting-state functional MRI study on amplitude of low-frequency fluctuation and functional connectivity alteration of parkinson′s disease with apathy / 中华放射学杂志

Objective:To investigate the alterations of amplitude of low frequency fluctuation (ALFF) and functional connectivity (FC) in patients with Parkinson′s disease (PD) with apathy.Methods:From May 2016 to August 2019, PD patients and age-, gender-and education level-matched healthy controls (HC) in the First Affiliated Hospital of Nanjing Medical University were prospectively recruited. The clinical and resting-state functional MRI (rs-fMRI) data of PD patients and HC were analyzed. According to the Starkstein Apathy Scale (SAS) scores, PD patients were divided into PD with apathy (PD-A) group and PD without apathy (PD-NA) group. Rs-fMRI images were processed by DPABI based on MATLAB. ALFF values were calculated and the standard ALFF (zALFF) were obtained. ANOVA and Post-Hoc t test were performed to compare the differences in local brain activity among the three groups. The brain regions with significant different zALFF values were selected as the seeds to calculate the FC values of the whole brain. The associations between FC values and the SAS scores were performed using pearson correlation analyses. Results:A total of 75 PD patients (50 males, 25 females, aged from 44 to 88 years) and 41 HC (25 males, 16 females, aged from 54 to 72 years) were enrolled. There were 42 patients in the PD-A group and 33 patients in the PD-NA group. Significant differences were found in zALFF values among the PD-A, PD-NA and HC groups ( P<0.05). After Post-Hoc t test, compared with the HC group, zALFF values were significantly increased in the right middle frontal gyrus in the PD-A group ( P<0.05) and significantly decreased in the left precuneus in the PD-NA group; The zALFF values of the right middle frontal gyrus and left precuneus in the PD-A group were significantly higher than those in PD-NA group ( P<0.05). Brain regions with different zALFF values were used as seeds for whole-brain FC. Compared with PD-NA group, FC values between the right middle frontal gyrus and bilateral precuneus, left superior frontal gyrus and its medial side, left middle frontal gyrus, left angular, left anterior cingulate gyrus, left posterior cingulate gyrus, left parahippocampal gyrus were significantly decreased in the PD-A group ( P<0.05). Additionally, FC values of PD patients between the right middle frontal gyrus with the left precuneus, the left superior frontal gyrus and its medial side, and the left middle frontal gyrus were negatively correlated with SAS scores ( r=-0.31, -0.30 and -0.34, both P<0.05). Conclusion:PD-A and PD-NA patients have different brain functional activities and connections in the frontal lobe, parietal lobe and limbic system, suggesting that apathy in PD may be associated with the abnormal functional connections of the frontal-parietal cortical circuit and the frontal-limbic-striatal loop.

Study on Compound Musk in the treatment of hypertensive cerebral hemorrhage after operation / 中国医师进修杂志

Objective:To investigate the efficacy of Compound Musk combined with nimodipine combined with minimally invasive surgery in the treatment of hypertensive cerebral hemorrhage and the effects on serum inflammation, stress and apoptosis.Methods:Prospective research methods was used. A total of 118 patients with hypertensive intracerebral hemorrhage who received treatment in the First Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine from March 2017 to January 2021 were randomly divided into control group and Compound Musk group (59 cases in each group). After minimally invasive surgery, patients in the control group were treated with nimodipine on the basis of conventional treatment, while patients in the Compound Musk group were treated with compound musk on the basis of the control group. After 2 weeks, the efficacy was evaluated and the levels of serum inflammatory indexes, oxidative stress indexes and apoptosis indexes were measured.Results:The total effective rate in Compound Musk group was higher than that in control group: 98.3% (58/59) vs. 88.1% (52/59), and the difference was statistically significant ( P<0.05). After 2 weeks of treatment, serum inflammatory indexes including nuclear factor-κB (NF-κB), interleukin-1β (IL-1β), matrix metalloproteinase-3 (MMP-3), matrix metalloproteinase-9 (MMP-9); apoptosis indexes including soluble Fas receptor (sFas), soluble Fas ligand (sFAS-L); oxidative stress indexes including advanced oxidation protein products (AOPP), malondialdehyde (MDA) decreased, and some oxidative stress indexes including glutathione peroxidase (GSH-Px), catalase (CAT) increased. The levels of the above inflammatory indexes, apoptosis indexes and oxidative stress indexes in Compound Musk group were lower than those in control group, NF-κB: (18.96 ± 2.17) ng/L vs. (24.10 ± 3.23) ng/L, IL-1β: (12.88 ± 1.74) ng/L vs. (15.19 ± 1.63) ng/L, MMP-3: (5.62 ± 0.95) ng/L vs. (7.97 ± 0.86) ng/L, MMP-9: (7.07 ± 0.86) ng/L vs. (9.26 ± 1.13) ng/L, sFas: (3.24 ± 0.38) μg/L vs. (4.19 ± 0.53) μg/L, sFas-L: (209.17 ± 24.39) ng/L vs. (288.54 ± 37.61) ng/L, AOPP: (10.76 ± 1.84) μg/L vs. (13.51 ± 2.09) μg/L, MDA: (2.87 ± 0.32) μmol/L vs. (3.45 ± 0.34) μmol/L, and the differences were statistically significant ( P<0.05). Some of the above oxidative stress indexes were higher than those in control group, GSH-Px: (3 274.91 ± 376.09) U/L vs. (2 854.19 ± 325.22) U/L, CAT: (60.82 ± 7.43) U/L vs. (52.17 ± 6.48) U/L, the differences were statistically significant ( P<0.05). During treatment, there was no significant difference in the incidence of rash, diarrhea, drug-induced liver and myocardial injury between two groups ( P>0.05). Conclusions:Compound Musk has a positive effect on improving the curative effect and internal environment of patients with hypertensive intracerebral hemorrhage after minimally invasive surgery, and will not increase the occurrence of serious adverse reactions.

Material Basis and Pharmacological Action of Tongxie Yaofang： A Review / 中国实验方剂学杂志

Tongxie Yaofang， also known as Baizhu Shaoyaosan， was first recorded in Danxi's Experiential Therapy （《丹溪心法》） by ZHU Danxi in the Yuan dynasty. It is composed of Atractylodis Macrocephalae Rhizoma， Paeoniae Radix Alba， Citri Reticulatae Pericarpium， and Saposhnikoviae Radix， and serves as the representative prescription for the treatment of painful diarrhea. It has the functions of tonifying the spleen， emolliating the liver， relieving pain， and checking diarrhea， and is mainly used in the treatment of gastrointestinal diseases such as irritable bowel syndrome （IBS） and ulcerative colitis （UC）. In addition， it is effective in treating gastrointestinal disorders with mental and psychological abnormalities， as well as obstinate anorexia in children， depression syndrome， and respiratory diseases. Experimental research and clinical practice have shown that Tongxie Yaofang has multi-component， multi-pathway， and multi-target characteristics in the treatment of diseases. The mechanism of Tongxie Yaofang in treating diseases is mainly attributed to anti-inflammation， immune function regulation， intestinal hypersensitivity improvement， emotion regulation， etc. Monoterpene glycosides， flavonoids， chromones， lactones， and other components contained play an important therapeutic role. The research on the systems biology of Tongxie Yaofang， such as metabolomics， proteomics， and network pharmacology， provides a scientific basis for clarifying its mechanism of action and expanding its clinical application. However， there are still some problems to be solved， such as difficulty in combining diseases and syndromes and lack of in-depth systematic research. Through the retrieval and collation of relevant literature， this paper systematically reviewed the material basis， pharmacological effects， and systems biology research of Tongxie Yaofang， aiming to lay a foundation for in-depth research on its mechanism in treating diseases and rational application in clinical practice.

Anti-colorectal Cancer Mechanism of Zuojinwan and Its Main Monomer Components： A Review / 中国实验方剂学杂志

Zuojinwan is a classic Chinese medicine prescription recorded in the Danxi's Experiential Therapy， with Coptidis Rhizoma and Euodiae Fructus in a ratio of 6 ∶ 1. It can treat symptoms such as liver fire hypochondriac pain， stomach duct pain， vomiting， and acid swallowing. There are many pharmacological studies on Zuojinwan in modern times， especially in the digestive tract， but the prescription also has its unique effect on digestive tract cancer， and its anti-tumor studies mainly focus on colorectal cancer and gastric cancer. Colorectal cancer is the third most common type of cancer in the world and the second deadliest malignancy. At present， a number of studies have shown that the basic pharmacological studies of anti-colorectal cancer by Zuojinwan include the proliferation， apoptosis， invasion， energy metabolism， epigenetics， and drug resistance of colorectal cancer. Alkaloids are the main active ingredients of Zuojinwan， such as berberine， evodiamine， coptisine， palmatine， and rutaecarpine. Compared with the effect of Zuojinwan on colorectal cancer， studies on the effect of berberine and evodiamine on tumor angiogenesis， tumor-promoting inflammation， and intestinal flora are carried out， except the studies on the resistance of berberine and the effect of evodiamine on energy metabolism. In addition， coptisine， palmatine， and rutaecarpine can regulate the proliferation， apoptosis， and metastasis of colorectal cancer cells， the proliferation and apoptosis of colorectal cancer cells， tumor-promoting inflammatory response， and the proliferation， migration， and invasion of colorectal cancer cells， respectively. Moreover， other studies have shown that the combination of berberine and evodiamine can have a synergistic effect on the growth， migration， and invasion of colorectal cancer cells and can reduce the cardiac toxicity induced by evodiamine. Therefore， this paper summarizes the studies on the anti-colorectal cancer mechanism of Zuojinwan and its main monomer components in recent years， so as to provide a theoretical basis for future clinical research and development of new high-efficiency and low-toxicity anti-colorectal cancer drugs and lay a solid foundation for clinical practice.

CT imaging features of bronchiolar adenoma / 中华放射学杂志

Objective:To investigate the CT characteristics of bronchiolar adenoma (BA) in order to improve the understanding of the disease and to increase the accuracy of preoperative diagnosis.Methods:The clinical, imaging and pathological data of 69 patients with BA confirmed by surgical resection and pathology at Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences from December 2018 to November 2020 were retrospectively reviewed. The type, the location and the size of the lesions, the distance from the lesion to the adjacent pleura, as well as the morphological characteristics including lobulation, spiculation, bubble lucency and pleural indentation were analyzed and recorded. The follow-up CT data were also reviewed.Results:Among 69 BAs, pre-operation chest CT displayed visible lesion in 25 cases, and showed negative in 44 cases. According to the lesion density, the 25 BAs on CT images were classified into solid type ( n=8), ground-glass type ( n=8), cystic type ( n=6) and cyst type ( n=3). There were 15 lesions in the right lung (1 in the upper, 2 in the middle and 12 in the lower lobe) and 10 lesions in the left lung (5 in the upper and 5 in the lower lobe). Ten lesions were found adjacent to the pleura. As for the other 15 cases, the distance between the lesion and the adjacent pleura was (10±7) mm. Calcification was displayed in one cystic type BA case. The maximum diameter of 25 BAs were 4.4-30.3 mm, with the median value of 9.6 mm. The lobulation, spiculation, bubble lucency, and pleural indentation of lesions were detected in 20, 11, 12, and 6 cases. In total there were 11 patients received the preoperative follow-up CT, and 4 cases showed enlargement in diameter (including 2 cases of solid type, 1 of ground-glass type and 1 of cystic type). The growth rate was 0.43-2.14 mm/year, with the median value of 1.67 mm/year. Imaging signs including spiculation ( n=1), bubble lucency ( n=1) and lobulation ( n=1) were newly discovered on the preoperative follow-up CT. Postoperative follow-up CT was performed in 13 cases, without any recurrence or metastasis found. Conclusions:CT imaging features of BA usually display as a single pulmonary solid or ground-glass nodule, and also can be presented as cystic or cyst type in several cases. Lesions can appear the lobulation, spiculation and bubble lucency, with calcification rarely found. A few of BA cases can enlarge during follow-up.

Expert consensus on nucleic acid amplification test of respiratory pathogens in children / 中华实用儿科临床杂志

Acute respiratory tract infection is the most common infectious disease in children, which seriously threatens children′s health.Rapid and accurate etiological diagnosis is of great significance for the clinical treatment and control of these diseases.Pathogen nucleic acid test was applied and became the main method of respiratory tract infection diagnosis for its high sensitivity and specificity.To regulate the application of pathogen nucleic acid amplification test in respiratory tract infection in children, improve the diagnosis level, expert consensus on nucleic acid amplification test of respiratory pathogens in children was prepared to guide the application and promote pathogens diagnosis ability.

Aging-elevated inflammation promotes DNMT3A R878H-driven clonal hematopoiesis

Aging-elevated DNMT3A R882H-driven clonal hematopoiesis (CH) is a risk factor for myeloid malignancies remission and overall survival. Although some studies were conducted to investigate this phenomenon, the exact mechanism is still under debate. In this study, we observed that DNMT3A R878H bone marrow cells (human allele: DNMT3A R882H) displayed enhanced reconstitution capacity in aged bone marrow milieu and upon inflammatory insult. DNMT3A R878H protects hematopoietic stem and progenitor cells from the damage induced by chronic inflammation, especially TNFα insults. Mechanistically, we identified that RIPK1-RIPK3-MLKL-mediated necroptosis signaling was compromised in R878H cells in response to proliferation stress and TNFα insults. Briefly, we elucidated the molecular mechanism driving DNMT3A R878H-based clonal hematopoiesis, which raises clinical value for treating DNMT3A R882H-driven clonal hematopoiesis and myeloid malignancies with aging.

An ultrapotent RBD-targeted biparatopic nanobody neutralizes broad SARS-CoV-2 variants

The wide transmission and host adaptation of SARS-CoV-2 have led to the rapid accumulation of mutations, posing significant challenges to the effectiveness of vaccines and therapeutic antibodies. Although several neutralizing antibodies were authorized for emergency clinical use, convalescent patients derived natural antibodies are vulnerable to SARS-CoV-2 Spike mutation. Here, we describe the screen of a panel of SARS-CoV-2 receptor-binding domain (RBD) targeted nanobodies (Nbs) from a synthetic library and the design of a biparatopic Nb, named Nb1-Nb2, with tight affinity and super wide neutralization breadth against multiple SARS-CoV-2 variants of concern. Deep-mutational scanning experiments identify the potential binding epitopes of the Nbs on the RBD and demonstrate that biparatopic Nb1-Nb2 has a strong escape resistant feature against more than 60 tested RBD amino acid substitutions. Using pseudovirion-based and trans-complementation SARS-CoV-2 tools, we determine that the Nb1-Nb2 broadly neutralizes multiple SARS-CoV-2 variants, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Lambda (C.37), Kappa (B.1.617.1) and Mu (B.1.621). Furthermore, a heavy chain antibody is constructed by fusing the human IgG1 Fc to Nb1-Nb2 (designated as Nb1-Nb2-Fc) to improve its neutralization potency, yield, stability and potential half-life extension. For the new Omicron variant (B.1.1.529) that harbors unprecedented multiple RBD mutations, Nb1-Nb2-Fc keeps a firm affinity (KD < 1.0x10-12 M) and strong neutralizing activity (IC50 = 0.0017 nM). Together, we developed a tetravalent biparatopic human heavy chain antibody with ultrapotent and broad-spectrum SARS-CoV-2 neutralization activity which highlights the potential clinical applications.

Analysis of viral RNA-host protein interactomes enables rapid antiviral drug discovery

RNA viruses including SARS-CoV-2, Ebola virus (EBOV), and Zika virus (ZIKV) constitute a major threat to global public health and society. The interactions between viral genomes and host proteins are essential in the life cycle of RNA viruses and thus provide targets for drug development. However, viral RNA-host protein interactions have remained poorly characterized. Here we applied ChIRP-MS to profile the interactomes of human proteins and the RNA genomes of SARS-CoV-2, EBOV, and ZIKV in infected cells. Integrated interactome analyses revealed interaction patterns that reflect both common and virus-specific host responses, and enabled rapid drug screening to target the vulnerable host factors. We identified Enasidenib as a SARS-CoV-2 specific antiviral agent, and Trifluoperazine and Cepharanthine as broad spectrum antivirals against all three RNA viruses. One Sentence SummaryInteractome analyses of host proteins and the SARS-CoV-2, EBOV, and ZIKV RNA genomes unveil viral biology and drug targets.

Ultrapotent SARS-CoV-2 neutralizing antibodies with protective efficacy against newly emerged mutational variants

Accumulating mutations in the SARS-CoV-2 Spike (S) protein can increase the possibility of immune escape, challenging the present COVID-19 prophylaxis and clinical interventions. Here, 3 receptor binding domain (RBD) specific monoclonal antibodies (mAbs), 58G6, 510A5 and 13G9, with high neutralizing potency blocking authentic SARS-CoV-2 virus displayed remarkable efficacy against authentic B.1.351 virus. Each of these 3 mAbs in combination with one neutralizing Ab recognizing non-competing epitope exhibited synergistic effect against authentic SARS-CoV-2 virus. Surprisingly, structural analysis revealed that 58G6 and 13G9, encoded by the IGHV1-58 and the IGKV3-20 germline genes, both recognized the steric region S470-495 on the RBD, overlapping the E484K mutation presented in B.1.351. Also, 58G6 directly bound to another region S450-458 in the RBD. Significantly, 58G6 and 510A5 both demonstrated prophylactic efficacy against authentic SARS-CoV-2 and B.1.351 viruses in the transgenic mice expressing human ACE2 (hACE2), protecting weight loss and reducing virus loads. These 2 ultrapotent neutralizing Abs can be promising candidates to fulfill the urgent needs for the prolonged COVID-19 pandemic.

Genome-wide CRISPR activation screen identifies novel receptors for SARS-CoV-2 entry

The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been endangering worldwide public health and economy. SARS-CoV-2 infects a variety of tissues where the known receptor ACE2 is low or almost absent, suggesting the existence of alternative pathways for virus entry. Here, we performed a genome-wide barcoded-CRISPRa screen to identify novel host factors that enable SARS-CoV-2 infection. In addition to known host proteins, i.e. ACE2, TMPRSS2 and NRP1, we identified multiple host components, among which LDLRAD3, TMEM30A and CLEC4G were confirmed as functional receptors for SARS-CoV-2. All these membrane proteins bind directly to spikes N-terminal domain (NTD). Their essential and physiological roles have all been confirmed in either neuron or liver cells. In particular, LDLRAD3 and CLEC4G mediate SARS-CoV-2 entry and infection in a fashion independent of ACE2. The identification of the novel receptors and entry mechanisms could advance our understanding of the multiorgan tropism of SARS-CoV-2, and may shed light on the development of the therapeutic countermeasures against COVID-19.

Circular RNA Vaccines against SARS-CoV-2 and Emerging Variants

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its emerging variants of concern (VOC), such as Delta (B.1.617.2) and Omicron (B.1.1.529), has continued to drive the worldwide pandemic. Therefore, there is a high demand for vaccines with enhanced efficacy, high thermostability, superior design flexibility, and fast manufacturing speed. Here, we report a circular RNA (circRNA) vaccine that encodes the trimeric RBD of SARS-CoV-2 Spike protein. Without the need of nucleotide modification, 5-capping or 3-polyadenylation, circRNA could be rapidly produced via in vitro transcription and is highly thermostable whether stored in naked or lipid-nanoparticle (LNP)-encapsulated format. LNP-encapsulated circRNARBD elicited potent neutralizing antibodies and T cell responses, providing robust protection against Beta (B.1.351) and native viruses in mice and rhesus macaques, respectively. Notably, circRNA vaccine enabled higher and more durable antigen production than 1m{Psi}-modified mRNA vaccine, eliciting a higher proportion of neutralizing antibodies and stronger Th1-biased immune responses. Importantly, we found that circRNARBD-Omicron vaccine induced effective neutralizing antibodies against only Omicron but not Delta variant. By contrast, circRNARBD-Delta could elicit high level of neutralizing antibodies against both Delta and Omicron. Following two doses of either native- or Delta-specific vaccination, circRNARBD-Delta, but not Omicron or Beta vaccines, could effectively boost the neutralizing antibodies against both Delta and Omicron variants. These results suggest that circRNARBD-Delta is a favorable choice for vaccination to provide a broad-spectrum protection against the current variants of concern of SARS-CoV-2.

The curative effect of suture anchor in the treatment of ankle joint fracture with distal tibiofibular syndesmosis injury / 中华骨科杂志

Objective:To investigate the curative effect of suture anchor in the treatment of ankle joint fracture complicated with distal tibiofibular syndesmosis injury.Methods:From January 2017 to August 2019, data of 65 patients with Weber C type ankle fracture combined with posterior malleolus fracture in our hospital who underwent surgical treatment were retrospectively analyzed and were divided into two groups according to the treatment method of injury: suture-anchor repair group (suture-anchor was used to repair the anterior inferior tibiofibular ligament) and screw fixation group (cortical bone screw was used to fix the tibiofibular syndesmosis). Among them, 17 cases were treated with suture-anchors to repair the anterior inferior tibiafibular ligament, including 7 males, 10 females, 11 left and 6 right. In the Lauge-Hanson subgroup, there were 10 cases of pronation external rotation (PER), and 7 cases of pronation abduction (PA). The mean age was 43.76±15.83 years old. Forty-eight patients were treated with cortical screw fixation, including 33 males, 15 females, 34 left and 14 right. In the Lauge-Hanson subgroup, there were 30 cases of PER, and 18 cases of PA. The mean age was 39.90±13.57 years old. The differences in operation time, number of fluoroscopy, quality of reduction and postoperative complications were compared between the two groups. The ankle joint function was compared at 16 weeks postoperatively and at the last follow-up. The ankle joint function score was based on the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score.Results:All the 65 patients were followed up and the average follow-up time of 65 cases was 16.88±4.46 months. All the fractures were clinically healed 12-16 weeks after operation. The operative time of screw fixation group was 123.71±41.36 min, and the number of fluoroscopy was 25.17±16.29 times, while the operative time of suture-anchor repair group was 99.94±24.16 min and the number of fluoroscopy was 16.26±10.58 times. The difference between the two groups was statistically significant ( t=2.048, 2.175; P=0.045, 0.033). In the screw fixation group, the mean anterior and posterior distance of the tibiofibular syndesmosis was 3.15±1.35 mm, and 6.48±1.43 mm, respectively. In the suture-anchor repair group, the mean anterior distance of the syndesmosis was 2.06±1.47 mm, and the mean posterior distance of the syndesmosis was 6.76±1.78 mm. There was statistically significant difference in the distance of anterior distance of the syndesmosis ( t=3.328, P=0.002), while there was no statistically significant difference in the posterior distance of the syndesmosis ( t=0.701, P=0.486). The incidence of postoperative complications was 16.67% (8/48) in the screw fixation group and 5.88% (1/17) in the suture-anchor repair group, which was no statistically different ( χ2=1.282, P=0.258). The excellent and good rates of AOFAS ankle-hindfoot scores were 91.67% (44/48) in the screw fixation group and 88.24% (15/17) in the suture-anchor repair group at 16 weeks; 95.83% (46/48) in the screw fixation group and 94.12% (16/17) in the suture-anchor repair group at the last follow-up. There was no significant difference ( P >0.05). Conclusion:Compare with screw fixation in the treatment of acute distal tibiofibular syndesmosis injury, suture-anchor repair of anterior inferior tibiofibular ligament is a safe and effective method. It can increase the anatomical reduction rate of anterior distance of the syndesmosis, and reduce the operation time without increasing the incidence of complications.

Investigation and analysis of an extensive skin injury to the back caused by accidental irradiation in interventional procedure / 中华放射医学与防护杂志

Objective:To carry out investigation and analysis of an extensive skin radiation injury to the back accidentally caused by interventional procedure and to explore the problems faced in the event with emphasis on avoiding the reoccurance of similar events in the future.Methods:The data were collected by consulting the patient′s detailed medical history, collecting and analyzing clinical diagnosis and treatment data, tracking and observing their clinical manifestations and signs. The patient′s peripheral blood samples were also collected, together with the biological dose estimated and the equipment data collected on the site of the interventional treatment hospital.Results:The whole body dose to the patient was estimated to be 0.95 Gy. The typical values of kerma rate of radiation incident on the body surface due to fluoroscopic procedures were 373.5 mGy/min in subtraction modality and 47.8 mGy/min in fluoroscopy modality, respectively. The annual effective dose to the interventional radiologist was 20.51 mSv due to his operation in long-time radiation exposure conditions, higher than 3.09 mSv for other interventional radiologists with similar workload in the same department. The whole body and local clinical manifestations of the patients were in line with radiation injury. No clear diagnosis has been obtained in several hospitals, nor can obvious treatment outcomes be obsevered.Conclusion:Combined with the biological dose estimation result and clinical manifestations, the case was diagnosed as degree Ⅳ skin radiation injury. Radiation injury is closely related to whether the operation is conducted according to the standard and the output dose of X-ray machine. Non-specialized hospitals should strengthen clinical diagnosis and treatment of radiation injury.

Research progress on host restriction factors of respiratory viruses / 中华实用儿科临床杂志

Respiratory viruses can cause a variety of serious respiratory infections and diseases of tissues and organs outside the respiratory tract, raising a potentially severe threat to the society.Virus replication and survival rely on the internal mechanism of host cells, and the latter also produce a variety of restriction factors that target viral invasion, genome transcription and replication, and assembly and release to block viral infection.Herein, this study reviewed the research progress of the antiviral effects of the host restriction factors of common respiratory viruses and their underlying mechanisms.

Corilagin inhibits SARS-CoV-2 replication by targeting viral RNA-dependent RNA polymerase

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has become one major threat to human population health. The RNA-dependent RNA polymerase (RdRp) presents an ideal target of antivirals, whereas nucleoside analogs inhibitor is hindered by the proofreading activity of coronavirus. Herein, we report that corilagin (RAI-S-37) as a non-nucleoside inhibitor of SARS-CoV-2 RdRp, binds directly to RdRp, effectively inhibits the polymerase activity in both cell-free and cell-based assays, fully resists the proofreading activity and potently inhibits SARS-CoV-2 infection with a low 50% effective concentration (EC

Exploring early prevention and control of COVID-19 outbreak based on system dynamics model analysis / 浙江大学学报·医学版

To explore early prevention and control of coronavirus disease 2019 （COVID-19） outbreak based on system dynamics model analysis. The data of early outbreak of COVID-19 were collected from the World Health Organization，covering countries of the China，United States，United Kingdom，Australia，Serbia and Italy. The susceptible-exposed-infected-recovered （SEIR） model was generalized and then its parameters were optimized. According to the parameters in the basic infection number expression，the sensitivity in the system dynamics model was used to quantitatively analyze the influence of the protection rate，infection rate and average quarantine time on the early spread of the outbreak. Based on the analysis results，targeted prevention and control measures for the early outbreak of COVID-19 were proposed. The generalized SEIR model had a good fit for the early prediction and evaluation of COVID-19 outbreaks in six countries. The spread of COVID-19 was mainly affected by the protection rate，infection rate and average quarantine time. The improvement of the protection rate in the first ays was the most important:the greater the protection rate，the fewer the number of confirmed cases. The infection rate in the first 5 days was the most critical:the smaller the infection rate，the fewer the number of confirmed cases. The average quarantine time in the first 5 days was very important:the shorter the average quarantine time，the fewer the number of confirmed cases. Through the comparison of key parameters of six countries，Australia and China had implemented strict epidemic prevention policies，which had resulted in good epidemic prevention effects. In the early stage of the outbreak，it is necessary to improve the protection rate，shorten the average quarantine time，and implement strict isolation policies to curb the spread of COVID-19.

The Rhinolophus affinis bat ACE2 and multiple animal orthologs are functional receptors for bat coronavirus RaTG13 and SARS-CoV-2

Bat coronavirus (CoV) RaTG13 shares the highest genome sequence identity with SARS-CoV-2 among all known coronaviruses, and also uses human angiotensin converting enzyme 2 (hACE2) for virus entry. Thus, SARS-CoV-2 is thought to have originated from bat. However, whether SARS-CoV-2 emerged from bats directly or through an intermediate host remains elusive. Here, we found that Rhinolophus affinis bat ACE2 (RaACE2) is an entry receptor for both SARS-CoV-2 and RaTG13, although RaACE2 binding to the receptor binding domain (RBD) of SARS-CoV-2 is markedly weaker than that of hACE2. We further evaluated the receptor activities of ACE2s from additional 16 diverse animal species for RaTG13, SARS-CoV, and SARS-CoV-2 in terms of S protein binding, membrane fusion, and pseudovirus entry. We found that the RaTG13 spike (S) protein is significantly less fusogenic than SARS-CoV and SARS-CoV-2, and seven out of sixteen different ACE2s function as entry receptors for all three viruses, indicating that all three viruses might have broad host rages. Of note, RaTG13 S pseudovirions can use mouse, but not pangolin ACE2, for virus entry, whereas SARS-CoV-2 S pseudovirions can use pangolin, but limited for mouse, ACE2s enter cells. Mutagenesis analysis revealed that residues 484 and 498 in RaTG13 and SARS-CoV-2 S proteins play critical roles in recognition of mouse and human ACE2. Finally, two polymorphous Rhinolophous sinicus bat ACE2s showed different susceptibilities to virus entry by RaTG13 and SARS-CoV-2 S pseudovirions, suggesting possible coevolution. Our results offer better understanding of the mechanism of coronavirus entry, host range, and virus-host coevolution.

Identification of Cross-Reactive CD8+ T Cell Receptors with High Functional Avidity to a SARS-CoV-2 Immunodominant Epitope and Its Natural Mutant Variants

Despite the growing knowledge of T cell responses and their epitopes in COVID-19 patients, there is a lack of detailed characterizations for T cell-antigen interactions and T cell functions. Using a peptide library predicted with HLA class I-restriction, specific CD8+ T cell responses were identified in over 75% of COVID-19 convalescent patients. Among the 15 SARS-CoV-2 epitopes identified from the S and N proteins, N361-369 (KTFPPTEPK) was the most dominant epitope. Importantly, we discovered 2 N361-369-specific T cell receptors (TCRs) with high functional avidity, and they exhibited complementary cross-reactivity to reported N361-369 mutant variants. In dendritic cells (DCs) and the lung organoid model, we found that the N361-369 epitope could be processed and endogenously presented to elicit the activation and cytotoxicity of CD8+ T cells ex vivo. Our study evidenced potential mechanisms of cellular immunity to SARS-CoV-2, illuminating natural ways of viral clearance with high relevancy in the vaccine development.