Tobacco mosaic virus (TMV) causes significant yield loss in susceptible crops irrigated with contaminated water. However, detection of TMV in water is difficult owing to extremely low concentrations of the virus. Here, we developed a simple method for the detection and quantiifcation of TMV in irrigation water. TMV was reliably detected at concentrations as low as 10 viral copies/μL with real-time PCR. The sensitivity of detection was further improved using polyethylene glycol 6000 (PEG6000, MW 6000) to concentrate TMV from water samples. Among the 28 samples from Shaanxi Province examined with our method, 17 were tested positive after virus concentration. Infectivity of TMV in the original water sample as well as after concentration was conifrmed using PCR. The limiting concentration of TMV in water to re-infect plants was determined as 102 viral copies/mL. The method developed in this study offers a novel approach to detect TMV in irrigation water, and may provide an effective tool to control crop infection.

Objective To detect the serum levels of CC chemokine receptor 2(CCR2)and C-reactive pro-tein(CRP)in stroke patients,and analyze their relationship with the severity of stroke associated pneumonia and their clinical significance.Methods A total of 78 patients with stroke associated pneumonia who were di-agnosed and treated in the hospital from October 2022 to February 2023 were collected as the study group,ac-cording to the severity of pneumonia,the study group was divided into mild group(31 cases),moderate group(29 cases),and severe group(18 cases),78 stroke patients who did not develop pneumonia were included into control group.Pearson method was applied to analyze the correlation between serum CCR2 and CRP levels in stroke associated pneumonia patients.Multivariate Logistic regression was applied to analyze the factors influ-encing the occurrence of stroke associated pneumonia.Receiver operating characteristic(ROC)curve was ap-plied to analyze the diagnostic value of serum CCR2 and CRP for stroke associated pneumonia.Results The National Institute of Health stroke scale(NIHSS)score,serum CCR2,and CRP levels in the study group were obviously higher than those in the control group(P<0.05).The levels of serum CCR2 and CRP increased with the aggravation of pneumonia(P<0.05).The levels of serum CCR2 and CRP in the study group were positively correlated(r=0.799,P<0.05).NIHSS score,CCR2,and CRP levels were risk factors for stroke associated pneumonia in stroke patients(P<0.05).The area under the curve(AUC)for the diagnosis of stroke associated pneumonia using serum CCR2 and CRP alone was 0.873 and 0.888,respectively,and the AUC for the combined detection of the two was 0.936,the combined detection of the two was superior to the individual detection of serum CCR2 and CRP(Zcombination-CCR2=1.987,Zcombination-CRP=1.832,P=0.041,0.047).Conclusion Serum CCR2 and CRP are closely related to the severity of stroke associated pneumonia,and their combined detection has high diagnostic value for stroke associated pneumonia.

Objective To explore the difference in gut microbiota composition between patients with obstructive sleep apnea(OSA)and healthy individuals and the role of gut microbiota in the pathogenesis of OSA.Methods Thirty-nine patients with OSA admitted to our hospital between May and December,2022 and 20 healthy individuals were enrolled in this study.Stool samples were collected from all the participants for analysis of microbiome composition using 16S rRNA high-throughput sequencing analysis.The alpha diversity,beta diversity,and species difference were determined between the two groups and marker species analysis and metabolic pathway function prediction analysis were performed.Results The species diversity(Shannon and Simpson)indexes,richness(observed species)and evenness(Pielou)of gut microbiota were significantly lower in OSA patients than in the healthy individuals(P<0.05).The OSA patients had also a significantly lowered community diversity(P<0.05)with different gut microbial communities from those of the healthy individuals shown by increased relative abundance of potentially pathogenic bacteria such as Pseudomonas and Monocytogenes(P<0.05).LEfSe analysis showed that the abundance of 23 species of gut microbiota differed significantly between the two groups and the OSA patients had significant increases in the abundance of Pseudomonas,Meganomonas,and Fusobacterium(P<0.05).The differential marker flora affected host homeostasis.Random Forest and ROC curve analyses confirmed that Pseudomonas could be used as important biomarkers for a differential diagnosis.Metabolic pathway function prediction analysis showed that biosynthesis function had the greatest contribution to maintaining gut microbiota homeostasis,and Pseudomonas affected the occurrence and progression of OSA by participating in aromatic bioamine degradation and ketogluconic acid metabolic pathway.Conclusion OSA patients have obvious gut microbiota disturbances,and Pseudomonas may affect the development of OSA by participating in substance metabolism to serve as the potential target gut bacteria for OSA treatment.

Objective To explore the difference in gut microbiota composition between patients with obstructive sleep apnea(OSA)and healthy individuals and the role of gut microbiota in the pathogenesis of OSA.Methods Thirty-nine patients with OSA admitted to our hospital between May and December,2022 and 20 healthy individuals were enrolled in this study.Stool samples were collected from all the participants for analysis of microbiome composition using 16S rRNA high-throughput sequencing analysis.The alpha diversity,beta diversity,and species difference were determined between the two groups and marker species analysis and metabolic pathway function prediction analysis were performed.Results The species diversity(Shannon and Simpson)indexes,richness(observed species)and evenness(Pielou)of gut microbiota were significantly lower in OSA patients than in the healthy individuals(P<0.05).The OSA patients had also a significantly lowered community diversity(P<0.05)with different gut microbial communities from those of the healthy individuals shown by increased relative abundance of potentially pathogenic bacteria such as Pseudomonas and Monocytogenes(P<0.05).LEfSe analysis showed that the abundance of 23 species of gut microbiota differed significantly between the two groups and the OSA patients had significant increases in the abundance of Pseudomonas,Meganomonas,and Fusobacterium(P<0.05).The differential marker flora affected host homeostasis.Random Forest and ROC curve analyses confirmed that Pseudomonas could be used as important biomarkers for a differential diagnosis.Metabolic pathway function prediction analysis showed that biosynthesis function had the greatest contribution to maintaining gut microbiota homeostasis,and Pseudomonas affected the occurrence and progression of OSA by participating in aromatic bioamine degradation and ketogluconic acid metabolic pathway.Conclusion OSA patients have obvious gut microbiota disturbances,and Pseudomonas may affect the development of OSA by participating in substance metabolism to serve as the potential target gut bacteria for OSA treatment.

Objective To investigate the diagnostic value of serum soluble fms-like tyrosine kinase 1(sFlt-1)and soluble differentiation cluster 14(sCD14)in stroke-associated pneumonia(SAP).Methods A total of 67 SAP patients admitted to the hospital from March 2022 to January 2023 were selected as the study group,and 50 stroke patients without pneumonia during the same period were selected as the control group.Enzyme-linked immunosorbent assay was used to measure serum sFlt-1 and sCD14 levels.Pearson correlation analysis was used to analyze the correlation between serum sFlt-1,sCD14 levels and clinical data.Multivariate Logistic regression was used to analyze the influencing factors of SAP in patients with stroke.Receiver operating char-acteristic(ROC)curve was used to analyze the diagnostic value of serum sFlt-1 and sCD14 levels in predicting SAP in patients with stroke.Results The serum levels of sFlt-1 and sCD14 in SAP patients were higher than those in stroke patients without pneumonia and stroke patients with pneumonia alone(P＜0.05).SAP in stroke patients was associated with age,atrial fibrillation,heart failure,aspiration,dysphagia,brain stem stroke,proton pump inhibitor use,fever,cough,dyspnea,low-density lipoprotein cholesterol,procalcitonin(PCT),C-reactive protein,white blood cell count,national institutes of health stroke scale(NIHSS)score,clinical pulmonary infection(CPIS)score(P＜0.05).Correlation analysis showed that serum sFlt-1 level was positively correlated with sCD14(r=0.439,P＜0.001),and serum sFlt-1 and sCD14 levels were positively correlated with NIHSS score and CPIS score(P＜0.05).Multivariate Logistic regression analysis showed that sFlt-1,sCD14,proton pump inhibitor use,PCT,dysphagia,and age were the influencing factors of SAP in stroke patients(P＜0.05).ROC curve results showed that the area under the curve of serum sFlt-1 and sCD14 combined to evaluate SAP in stroke patients was higher than that of single detection(ZsFlt-1-combined=2.194,P=0.028,ZscD14-combined=2.310,P=0.002).Conclusion The serum levels of sFlt-1 and sCD14 are in-creased in SAP patients,and the combination of the two has a good diagnostic value for predicting the occur-rence of SAP.

Objective: To evaluate the efficiency of maxillary expansion with clear aligners and to analyze the possible influence factors. Methods: Thiry-one clear aligner cases (Invisalign) with maxillary expansion were enrolled in this study. The three-dimensional (3D) digital models of pre-treatment, planned in Clincheck software and post-treatment were collected. Upper dental arch width, buccal inclination of posterior teeth, and the expansion efficiency (expansion acquired/expansion planned) were measured and calculated. The impact of factors such as planned buccal inclination, planned expansion amount, attachment, and the mode of expansion on the expansion efficiency were analyzed. Results: The increases of upper arch width in canine, 1st and 2nd premolar, 1st and 2nd molar were (2.0±1.3), (2.8±1.5), (3.0±1.4), (1.8±1.0) and 0.5 (0.1, 1.1) mm, with their efficiency of 68%, 70%, 68%, 55% and 29%, respectively. The posterior teeth showed significantly more buccal inclination than the planned position (P<0.05). However, the most buccally inclined tooth detected in 1st molars was only 3.1°±3.9°. When the planned inter-molar width increase was less than 2 mm (n=15), the expansion efficiency of premolars was higher compared with those cases with the planned inter-molar width increase more than 2 mm (n=16, P<0.05). The planned buccal inclination, attachments, and the expansion mode had no significant effect on the expansion efficiency (P>0.05). Conclusions The expansion of maxillary arch with clear aligners was achieved by the buccal movement of the posterior teeth with limited buccal inclination. The efficiency of expansion declines from 1st premolars to second molars. The planned inter-molar width had a significant influence on the efficiency of premolar expansion.