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.

Objective:Patients with Laryngopharyngeal Reflux（LPR） have chronic inflammation of the laryngeal mucosa leading to a high response state in the larynx, which may make the vocal fold movement too fast. This paper discusses the characteristics of vocal fold movement and voice onset by analyzing laryngeal high-speed videoendoscopy in patients with LPR. Methods:Forty patients with LPR were enrolled as LPR group. The diagnostic criteria of LPR included positive reflux symptom index（RSI） and reflux syndrome score（RFS） to identify suspected LPR, objective oropharyngeal DX pH monitoring was carried out, and positive Ryan index indicated reflux. According to age and sex matching, 40 healthy volunteers were selected as the normal group. Laryngeal high-speed videoendoscopy, and the vocal fold motion and vibration parameters, including vocal fold adduction time, vocal fold abduction time, vocal fold vibration onset mode（vocal onset time and mode） and the opening quotient of vocal fold vibration cycle. Statistical analysis was performed using SPSS 25.0. Results:The time of vocal fold adduction in LPR group（mean 225.81ms） was less than that in normal group（mean 277.01 ms）, and the difference was statistically significant（P<0.05）. There was no significant difference in adduction time between LPR group and normal group（P>0.05）. The vocal onset time in LPR group was significantly longer than that in normal group（P<0.05）. High speed video endoscope showed that there were 17 patients with hard onset in LPR group and 8 patients with hard onset in normal group, the difference was statistically significant（P<0.05）. There was no significant difference in the open quotient of vocal fold vibration between LPR group and normal group（P>0.05）. The vocal fold abduction time in LPR group（mean 372.92 ms） was less than that in normal group（mean 426.98ms）, but the difference was not statistically significant（P>0.05）. The time difference of bilateral abduction of vocal fold in LPR group was significantly higher than that in normal group（P<0.05）. Conclusion:The larynx of LPR patients is in a high response state, the vocal fold moves faster, and it is more likely to have a hard vocal onset. These may result in voice dysfunction.
Humans ; Vocal Cords/physiopathology* ; Laryngopharyngeal Reflux/diagnosis* ; Laryngoscopy/methods* ; Male ; Video Recording ; Female ; Middle Aged ; Adult ; Voice/physiology* ; Case-Control Studies ; Vibration

Objective To investigate the differential metabolites of lymph node metastasis in pancreatic ductal carcinoma (PDAC) and provide new ideas for the pathogenesis, early diagnosis and treatment of metastatic pancreatic cancer. Methods Forty serum specimens of patients with pancreatic ductal carcinoma were collected and divided into lymph node metastasis group (18 cases) and non-metastasis group (22 cases). Thirty-one serum specimens were also collected from the healthy control group. Liquid chromatographytandem mass spectrometry was used to analyze the differential metabolites and metabolic pathways between patients with PDAC and healthy controls as well as between lymph node metastasis and non-metastasis groups. Results Principal component analysis and partial least squares-discriminant analysis revealed statistically significant differences in metabolites and metabolic pathways between patients with PDAC and the healthy controls and between lymph node metastasis and non-metastasis groups. The differences in profiles were also statistically significant. Seventy-six different metabolites and 11 metabolic pathways were screened between patients with PDAC and the healthy controls, among which phenylalanine metabolism and histidine metabolism were the two most influential metabolic pathways. Four different metabolites were screened between lymph node metastasis and non-metastasis groups, and the expression of ethopropazine and phenylalanine were upregulated but the expression of tetrahydrodeoxycorticosterone and oxprenolol were downregulated. Conclusion Metabolites are significantly altered in the lymph node metastasis group of patients with PDAC compared with the non-metastasis group. Ethopropazine, phenylalanine, tetrahydrodeoxy corticosterone, and oxprenolol are potential biomarkers of lymph node metastasis in patients with PDAC.

This study explores the application effect of the case-based teaching method based on Xuexitong learning platform in the online teaching of Digestive System, and analyzes the learner's emotional experience, learning behavior, and learning effect in the case-based online teaching. The results of the study show that the case-based online teaching model based on Xuexitong learning platform improves students' online learning interest, and the students have good emotional experience, high learning enthusiasm, good classroom interaction, enhanced self-learning ability before and after class, and good learning effect. In addition, precise teaching can be used for individual students who are not enthusiastic about online learning.

OBJECTIVES: The use of anticholinergic drugs in the elderly may lead to negative events such as falls, delirium, urinary retention and cognitive decline, and the higher the number of anticholinergic drugs use, the more such negative events occur. This study aims to analyze the risk factors associated with the prescription of total anticholinergic drugs in elderly outpatients and evaluate the rationality of anticholinergic drugs, and to provide a reference for reducing the adverse effects of anticholinergic drugs. METHODS: A list of drugs with anticholinergic activity based on the Beers criteria was established. The basic information (such as age and gender), clinical diagnosis, and medications of elderly outpatient were extracted from hospital electronic medical records, and the Anticholinergic Cognitive Burden (ACB) Scale was used to calculate the anticholinergic burden for each patient. Logistic regression analysis was used to identify the potential risk factors for the occurrence of problems such as multiple medication and insomnia. RESULTS: A total of 1 840 prescriptions for elderly patients were reviewed. Of these patients, ACB score was more than or equal to 1 in 648 (35.22%) patients. Number of prescription medication (95% CI: 1.221 to 1.336) and insomnia (95% CI: 3.538 to 6.089) were independent factors affecting ACB scores (both P<0.01). Medications for patients of ACB scores were most commonly treated with the central nervous system drugs (such as alprazolam and eszopiclone) and for the cardiovascular system drugs (such as metoprolol and nifedipine). CONCLUSIONS There is a high rate of ACB drugs use in geriatric patients, and the clinical focus should be on multiple medication prescriptions, especially on the central nervous system drugs (such as alprazolam and eszopiclone) and cardiovascular system drugs (such as metoprolol and nifedipine). The prescription review should be emphasized to reduce adverse reactions to anticholinergic drugs in elderly patients.
Humans ; Aged ; Cholinergic Antagonists/adverse effects* ; Outpatients ; Metoprolol ; Alprazolam ; Eszopiclone ; Nifedipine ; Sleep Initiation and Maintenance Disorders ; Risk Factors

Objective:To investigate the immune effects of Clostridium difficile toxoid B (CdtB) vaccine formulated with different mucosal adjuvants through microneedle immunization, and to provide ideas for the prevention and treatment of Clostridium difficile infection. Methods:CdtB vaccine was prepared with purified Clostridium difficile toxin B(TcdB) after formaldehyde detoxification. Female BALB/c mice were immunized with different doses of vaccine alone or in combination with mucosal adjuvants. The titers of specific serum IgG and fecal IgA were detected at 0 d, 7 d, 14 d, 28 d and 42 d after immunization. The protective effects of CdtB vaccine were evaluated by cell neutralization assay and Clostridium difficile challenge infection. Results:(1) With the increase of immune dose, the mice immunized with CdtB vaccine alone by microneedle not only produced better serum specific IgG, but also had higher level of IgA in feces. (2) When the mice were immunized with CdtB vaccine containing LT or CTB adjuvant by microneedle, the trend of serum specific IgG titer in each group increased with the increase of immune dose, especially in the group containing LT adjuvant. There were significant differences in the trend of specific IgA titer in feces between the adjuvant groups and the group without adjuvant, but the adjuvant effect was not obvious. (3) No significant difference in serum IgG titer was observed between the mice immunized with 10 μg CdtB by microneedle or intraperitoneal injection, but microneedle immunization significantly increased fecal IgA level. (4) The neutralization titers of specific antibodies in mouse serum after immunization and the test results of challenge protection in mice confirmed that the use of CdtB vaccine had certain protective effects.Conclusions:CdtB vaccine had better immune effects in mice through microneedle immunization, but the adjuvant effects of LT and CTB were not significant.

Objective:This study aims to explore the pathogenic roles of protein S-nitrosylation modification in the development of severe acute pancreatitis, and provide new insights into the molecular mechanisms driving acute pancreatitis development.Methods:Thirty two Sprague Dawley (SD) rats were randomly divided into sham operation group, mild acute pancreatitis (MAP) group, severe acute pancreatitis (SAP) group and SAP + N-nitro-L-arginine methyl ester (L-NAME) group (treated with nitric oxide synthase inhibitor), 8 rats in each group. All rats were sacrificed to take blood from heart and pancreatic tissues 24 h after model construction. Total protein S-nitrosylation modification level in pancreatic tissues was quantitated by the biotin-switch method, followed by histological evaluation via hematoxylin and eosin (HE) staining. The serum endotoxin, D-lactic acid, diamine oxidase, interleukin-6 and tumor necrosis factor-ɑ(TNF-ɑ), amylase, alanine aminotransferase, urea nitrogen and calcium ions in rat were detected. Pearson correlation analysis was used to analyze the correlation between each index and protein S-nitrosylation.Results:Compared with the sham operation group, the modification level of protein S-nitrosylation in pancreatic tissue of MAP group increased significantly ( P<0.05); Compared with MAP group, the modification level of protein S-nitrosylation in pancreatic tissue of SAP group increased significantly ( P<0.05); Compared with SAP group, the modification level of protein S-nitrosylation in pancreatic tissue of SAP + L-NAME group decreased significantly ( P<0.05). HE staining showed that the degree of pancreatic necrosis and inflammatory cell infiltration in SAP + L-NAME group were significantly weaker than those in SAP group. The concentrations of serum endotoxin, diamine oxidase, D-lactic acid, IL-6 and TNF-ɑ, amylase, alanine aminotransferase, and urea nitrogen in the MAP group were significantly higher than those in the sham operation group (all P<0.05); The above indexes in SAP group were significantly higher than those in MAP group and sham operation group (all P<0.05); The above indexes in SAP + L-NAME group were significantly lower than those in SAP group (all P<0.05). The serum IL-6 and TNF-ɑ levels in rats with acute pancreatitis were positively correlated with protein S-nitrosylation in pancreatic tissue (all P<0.05). Conclusions:Protein S-nitrosylation modification plays essential roles in the development and progression of severe acute pancreatitis.

Objective:To investigate the consistency of Velum, Oropharygneal, Tongue base, Epiglottis (VOTE) scores between two surgeons with similar clinical experience in obstructive sleep apnea hypopnea syndrome (OSAHS) patients with different degree of disease, and to analyze the influencing factors leading to the difference in score.Methods:This was a cross-sectional study. 64 preoperative drug-induced sleep endoscopy (DISE) videos of OSAHS patients during December 2014 to July 2018, from Nanfang Hospital, Southern Medical University were analyzed. The VOTE score was assessed single-blind by two similar experienced surgeons, and the Kappa value between the two scorers was calculated by the third researcher. According to the characteristics of the case, Fisher's exact test or chi-square test method was used to further explore the factors that influenced the consistency.Results:Sixty-four patients were divided into four groups according to the severity of the disease, including mild (7 cases), moderate (30 cases), severe(18 cases), and extremely severe (9 cases). The scores evaluated between two researchers were analysed for consistency. For mild patients, the two scorers were completely consistent in the configuration and degree of obstruction in the velum and epiglottis (Kappa=1). There was no agreement on whether obstruction or not, obstructed configuration, obstructed degree of the oropharynx and tongue base, and presence of velum and epiglottis obstruction. For moderate patients, the two scorers had a good consistency in the configuration and degree of the velum (0.61≤Kappa≤0.80), and there was no consistency in the evaluation of the degree of tongue base and epiglottis ( P>0.05). The consistency of the remaining obstructed conditions in the four planes was generally or moderate (0.21≤Kappa≤0.60). For patients with severe OSAHS, the two raters were completely consistent in the evaluation of palatopharyngeal and epiglottic planes for the presence of obstruction, but there was no consistency in the degree of obstruction. Although the degree of obstruction in the oropharyngeal plane can be assessed with good consistency, the consistency of whether the plane was blocked or not was generally not high. In the assessment of other obstructive conditions in the four planes of severe patients, the agreement between the two scorers was moderate or generally. For extremely severe patients, the two scorers were completely consistent in the evaluation of the velum obstruction, but there was no consistency in the degree of obstruction of the oropharynx and tongue base, and the obstruction configuration and degree of the epiglottis. The evaluation of other obstructed conditions in the four planes is good or moderate. Among the patients with severe OSAHS, the difference in the assessment of obstruction of the oropharynx was associated with tonsil size ( P<0.05). Conclusion:When physicians with similar clinical experience scored VOTE, the consistency of whether the velum and oropharyngeal planes are obstructed is related to the severity of the disease. Better consistency is observed among more severe OSAHS patients. The reason for the poor consistency of the oropharyngeal plane in severe OSAHS patients OSAHS is due to the difference of the tonsils size. For severe OSAHS patients with small tonsils, the assessment of whether the oropharynx is obstructed should be more cautious.

For ICU patients, a structured dental assessment and recording system can effectively prevent adverse nursing events caused by tooth loss, and eliminate the potential risk of patients' safety. In addition, the structured recording system can effectively speed up nursing document input, facilitate compliance and acceptance of dental assessment improve work efficiency and quality, and eventually improve the informationization management of nursing.

Objective: To investigate the history, risk factors for prognosis of malignant biliary stricture (MBS) patients receiving conservative therapy after endoscopic retrograde cholangiopancreatography(ERCP) and to set up a predictive model for overall survival (OS). Methods: MBS patients who underwent ERCP and conservative therapy in Xijing Hospital and PLA No.451 Hospital from January 2009 to December 2013 were enrolled to the present study. Predictive factors associated with OS were identified in the training cohort by stepwise multivariate Cox regression analysis. A predictive model was then developed and externally validated in the validation cohort. Results: Between January 2009 and December 2013, 152 and 149 patients were eligible to the training and validation cohort respectively. In the training cohort, tumors were mainly originated from bile duct (33.6%), pancreas (23.5%) or ampulla (20.4%). 76.3% (116/152) patients died during the observation period. The median OS for the training population was 5.0 months (3.9-6.2 months). CA19-9≥1 000 U/mL, non-ampulla tumor, metastasis, pre-ERCP total bilirubin≥7 mg/dL and hilar stricture were identified as independent predictive factors of poor OS (all P<0.05). Based on these factors, the COMTH predictive model was developed. The median OS of patients with COMTH>8 in the training and validation cohorts were both 3.0 months, which were significantly shorter than those with COMTH≤8 (10.0 and 6.9 months in the training and validation cohorts respectively, both P<0.001). Conclusion The prognosis of MBS patients undergoing ERCP is poor. The survival chance of patients with COMTH>8 is even more dismal.