Coronaviruses (CoVs) are generally associated with respiratory and enteric infections and have long been recognized as important pathogens of livestock and companion animals. Mouse hepatitis virus (MHV) is a widely studied model system for Coronavirus replication and pathogenesis. In this study, we created a MHV-A59 temperature sensitive (ts) mutant Wu"-ts18(cd) using the recombinant vaccinia reverse genetics system. Virus replication assay in 17C1-1 cells showed the plaque phenotype and replication characterization of constructed Wu"-ts18(cd) were indistinguishable from the reported ts mutant Wu"-ts 18. Then we cultured the ts mutant Wu"-ts 18(cd) at non-permissive temperature 39.5℃, which "forced" the ts recombinant virus to use second-site mutation to revert from a ts to a non-ts phenotype. Sequence analysis showed most of the revertants had the same single amino acid mutation at Nsp16 position 43. The single amino acid mutation at Nsp16 position 76 or position 130 could also revert the ts mutant Wu"-ts 18 (cd) to non-ts phenotype, an additional independent mutation in Nsp13 position 115 played an important role on plaque size. The results provided us with genetic information on the functional determinants of Nsp16. This allowed us to build up a more reasonable model of CoVs replication-transcription complex.

Thunder-fire wonder moxibustion is one of pressing moxibustion therapies and has a very good therapeutic effect on limb pains, furuncle-carbuncle and cold syndrome. To reveal the mechanism of clinical action of ancestors’ thunder-fire wonder moxibustion and seek the physical basis of its therapeutic advantage, this study, by a series of experiments, compared heat transfer regularities of thunder-fire wonder moxibustion versus pure moxa stick in simulated biological tissues under different conditions, preliminarily revealed heat radiation and heat transfer regularities of thunder-fire wonder moxibustion, tried to find pressing strength suitable for clinical operation of pressing moxibustion and had thoughts about changes in the clinical operation of past dynasties.

Objective To report our operative experience with aortic root replacement in 231 patients with aortic root aneurysm and discuss the current indications,methods,and surgical techniques.Methods Between January 1994 and August 1999,a group of 231 consecutive patients underwent aortic root replacement at our hospital,with 13 being treated on an emergency basis.There were 189 men and 42 women,ranging in age from 14 to 69 years.The diameter of the aneurysm varied from 4.5 to 11 cm.Among this group,145 had isolated aortic root aneurysms,65 suffered from DeBakey type Ⅰ aortic dissection,and the remaining 21 were diagnosed as having DeBakey type Ⅱ aortic dissection.Aortic valve regurgitation occurred in all cases.Aortic root replacement was performed with composite valved graft in 229 patients,and in 2 patients the aortic valve was preserved.Results The hospital mortality rate was 3.03%(7 patients).Early complications included re-exploration for bleeding in 6 patients,pericardial effusion in 9,as well as cerebral infarction,pleural effusion,and pneumothorax in 2 patients each.One hundred and seventy-five patients(78.12%)were followed up,with a mean follow-up time of 15.7 ± 13.1 months(range,2 weeks to 65 months).One patient died from lower-limb embolism and renal dysfunction 3 months postoperatively.Three patients died from postoperative anticoagulation accidents.The preoperative and postoperative mean left ventricular end-diastolic diameters were significantly different(68.1 ± 9.4 mm,range 54 to 112 mm;vs 54.8 ± 8.2 mm,range 38 to 88 mm;P＜0.001).Conclusions Once a diagnosis of acute aortic root dissecting aneurysm is made,the patient should undergo surgery as soon as possible if the general conditions permit.Aortic aneurysm without dissection or with chronic dissection should be operated if the diameter of the aneurysm is greater than 5 cm.

Objective To explore the methods of automatic identification of TCM terminology and to ex-pand the forms of natural language processing in TCM documents.Methods Based on the methods of conditional random field( CRF) , annotation and automatic identification on terms of symptoms, diseases, pulse-types and prescriptions recorded in Shanghan Lun as the research subjects, the effects of different combinations of the features, such as Chinese character itself, part of speech, word boundary and term category label, on identification of terminology were analyzed and the most effective combination was selected.Results The TCM terminology automatic identification model, combining with the features of Chinese character itself, part of speech, word boundary and term category label, had the precision of 85.00%, recall of 68.00%and F score of 75.56%.Conclusion The multi-features model of combi-nation of Chinese character itself, part of speech, word boundary and the term category label achieved the best identifying result in all combinations.

OBJECTIVETo analyze the relationship between the pathological features and 64-multislice spiral computed tomography (64-MSCT) findings of pulmonary nodules in autopsies from patients with coal workers' pneumoconiosis (CWP), to investigate the optimal imaging method for the distribution of pulmonary nodules, and to provide data for the establishment of CT diagnostic criteria for CWP.

METHODSCadaveric lung specimens were collected from 7 CWP patients. All of them were men, aged 42∼77 years (mean, 60.00±13.00 years), and their dust exposure time was 5∼30 years (mean, 15.4±8.01 years). The cadaveric lung specimens were treated by aeration, sectioning, and immobilization and were then examined by coronary 64-MSCT. The primitive images were reconstructed into the maximumintensity projection (MIP) images (slice thickness: 3 mm, 5 mm, and 8 mm). The sensitivities of imaging methods with different slice thickness were evaluated based on the pathology and anatomy of local pulmonary nodules, and the correlation between pathological results and radiological findings was analyzed.

RESULTSThere were significant differences between the stages determined by pathological examination and high-kV chest radiography (before death) (χ(2) = 4.667, P < 0.05; kappa value = 0.167, P < 0.05). A total of 271 nodules were found in all pathological sections, including peribronchovascular nodules (27, 9.9%), centrilobular nodules (67, 24.6%), interlobular nodules (65, 24.3%), nodules within 5 mm from the pleura (45, 16.5%), pleural plaque-like nodules on the lateral chest wall (45, 16.5%), and nodules on the interlobar pleura (22, 8.1%). The likelihood ratio was the highest (0.981) between 5-mm MIP images and pathological results according to the chi-square test.

CONCLUSIONThe stage of pulmonary nodules determined by pathological examination is significantly different from that determined by high-kV chest radiography. The 5-mm MIP images of 64-MSCT provide a good reflection of the local pathology and anatomy of pulmonary nodules in CWP patients.

Aged ; Anthracosis ; pathology ; Coal ; Coal Mining ; Dust ; Humans ; Lung ; pathology ; Male ; Middle Aged ; Pleural Diseases ; pathology ; Tomography, Spiral Computed

Objective:To explore the resistance to protease inhibitors (PI), nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and integrase inhibitors (INSTIs) of HIV-1 CRF55_01B and the transmission of drug-resistant strains among HIV-1 CRF55_01B infected patients before antiviral treatment in China.Methods:HIV-1 RNA was extracted from plasma samples of the patients infected with CRF55_01B in the national surveillance of HIV drug resistance before antiviral treatment in 2018. A 1 056 bp gene fragment of protease/reverse transcriptase (PR/RT) region and an 846 bp gene fragment of integrase (IN) region were obtained and sequenced. Drug resistance was analyzed by using all drugs included in the Stanford University HIV db Program, HIV-1 molecular network analysis was performed with software HIV-TRACE and polymorphism mutations of CRF55_01B integrase gene region were analyzed.Results:A total of 178 samples from 26 provinces, municipalities and autonomous regions in China were analyzed, and 170 sequences of CRF55_01B PR/RT region and 170 sequences of IN region of corresponding samples were obtained. The drug resistance rate was 15.3% (26/170). The drug resistance rates of PIs, NRTIs, NNRTIs and INSTIs were 1.2% (2/170), 1.2% (2/170), 15.3% (26/170), 0.6% (1/170), respectively. The level of drug resistance was mostly low. NNRTIs drug resistance mutations were mainly V179D/E co-appeared with other mutations, and 84.1% (143/170) of the infected patients carrying V179D/E alone showed potential drug resistance. INSTIs drug resistance mutation was G163R, and showed low resistance to EVG and RAL. The molecular network access rate was 30.0%(51/170)according to the 0.9% gene distance threshold. The resistant strains were transmitted between men with homosexual transmission and heterosexually transmitted people, and both carried resistant mutations E138G and V179E. In the integrase region, CRF55_01B and CRF01_AE and B subtypes showed high mutation frequency difference in 5 sites (T215A、G134N、I135V, K136R and L101I/V).Conclusions:Before antiviral treatment, CRF55_01B infected patients in China had a high resistance to NNRTIs. Strains carrying both E138G and V179E resistance mutations were transmitting in clusters. The prevalence of CRF55_01B integrase inhibitor resistant strains is low, but some genetic polymorphisms with high mutation rate in the integrase gene region have potential influence on drug sensitivity. The influence of drug resistance of new recombinant strains on antiviral therapy in China needs to be further monitored and analyzed.

We report a complete genomic sequence of rare isolates (minor genotype) of the SARS-CoV from SARS patients in Guangdong, China, where the first few cases emerged. The most striking discovery from the isolate is an extra 29-nucleotide sequence located at the nucleotide positions between 27,863 and 27,864 (referred to the complete sequence of BJ01) within an overlapped region composed of BGI-PUP5 (BGI-postulated uncharacterized protein 5) and BGI-PUP6 upstream of the N (nucleocapsid) protein. The discovery of this minor genotype, GD-Ins29, suggests a significant genetic event and differentiates it from the previously reported genotype, the dominant form among all sequenced SARS-CoV isolates. A 17-nt segment of this extra sequence is identical to a segment of the same size in two human mRNA sequences that may interfere with viral replication and transcription in the cytosol of the infected cells. It provides a new avenue for the exploration of the virus-host interaction in viral evolution, host pathogenesis, and vaccine development.
Base Sequence ; China ; Cluster Analysis ; Gene Components ; Genetic Variation ; Genome, Viral ; Genotype ; Molecular Sequence Data ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; SARS Virus ; genetics ; Sequence Analysis, DNA ; Severe Acute Respiratory Syndrome ; genetics