Geminiviruses cause substantial crop yield losses worldwide. The replication initiator protein (Rep) encoded by geminiviruses is indispensable for geminiviral replication. The Rep protein encoded by beet severe curly top virus (BSCTV, genus Curtovirus, family Geminiviridae) induces VARIANT IN METHYLATION 5 (VIM5) expression in Arabidopsis leaves upon BSCTV infection. VIM5 functions as a ubiquitination-related E3 ligase to promote the proteasomal degradation of methyltransferases, resulting in reduction of methylation levels in the BSCTV C2-3 promoter. However, the specific domains of Rep responsible for VIM5 induction remain poorly characterized. Although Rep proteins from several geminiviruses act as viral suppressors of RNA silencing (VSRs), whether BSCTV Rep also possesses VSR activity remains to be illustrated. In this study, we employed a transient expression system in the 16c-GFP transgenic and the wild-type Nicotiana benthamiana plants to analyze the VSR and the VIM5-inducing activities of different truncated Rep proteins haboring distinct domains. We found that the N-terminal domain (amino acids 1-180) of Rep suppressed GFP silencing in 16c-GFP transgenic N. benthamiana leaves. The minimal N-terminal fragment (amino acids 1-104) induced VIM5 expression upon co-infiltration, while C-terminal truncations lacked VIM5-inducing activity. Our results indicate that the N-terminal domain of Rep encoded by BSCTV mediates the suppression of RNA silencing and induces VIM5 expression. Thus, our findings contribute to a better understanding of interactions between geminiviral Rep and plant hosts.
Geminiviridae/genetics* ; Nicotiana/metabolism* ; Arabidopsis/metabolism* ; RNA Interference ; Viral Proteins/metabolism* ; Arabidopsis Proteins/metabolism* ; Plants, Genetically Modified/metabolism* ; Protein Domains ; Plant Diseases/virology* ; Methyltransferases/metabolism* ; Ubiquitin-Protein Ligases/metabolism* ; DNA Helicases/genetics*

Objective To investigate the effect of ventilation with different tidal volumes on respiratory mechanics and haemodynamics in children with severe pneumonia.Methods A total of 104 children with severe pneumonia were divided into the control group and the observation group using a random number table method,with 52 cases in each group.Both groups underwent mechanical ventilation treatment.The control group was treated with conventional tidal volume of 10-12 mL/kg,while the observation group was given a low tidal volume of 6-8 mL/kg.The respiratory mechanics indicators,hemodynamic indicators and inflammatory factor indicators before and after treatment were compared between the two groups.Results After treatment,the airway resistance(AR)and airway closing pressure(AOP)were lower in the observation group than those of the control group(P＜0.05),and pulmonary dynamic compliance(Cdyn)was higher in the observation group than that of the control group(P＜0.05).There were no significant differences in heart rate(HR),mean arterial pressure(MAP)and central venous pressure(CVP)after treatment between the two groups(P＜0.05).After treatment,the levels of interleukin(IL)-6,IL-8 and tumor necrosis factor-α(TNF-α)were all lower in the observation group than those in the control group(P＜0.05).Conclusion Small tidal volume mechanical ventilation is effective in improving the respiratory mechanics of children with severe pneumonia without causing large fluctuations in their hemodynamics.At the same time,it can reduce the level of inflammatory factors in the organism.

Objective:To analyze the epidemiological and clinical features of infectious diseases of the central nervous system (CNS).Methods:A cross-sectional study and analysis were conducted to summarize the epidemiological and clinical characteristics of 9 918 patients with CNS infectious diseases, who were diagnosed and treated at 29 hospitals across China from January 1, 2001 to December 31, 2020. Data collected included demographic data, clinical manifestations, health economic indicators, and prognostic outcomes.Results:Among the 9 918 collected cases of CNS infectious diseases, 5 559 were male (56.0%) and 4 359 were female (44.0%), with an onset age of 38 (25, 53) years. Education level: slightly more junior high school education (2 651 cases, 26.7%), and less elementary school education and below (2 181 cases, 22.0%) were found. Occupational distribution: farmers were found predominant (3 215 cases, 32.4%), followed by workers (1 826 cases, 18.4%) and students (1 633 cases, 16.5%). Clinical manifestations: headache (6 074 cases, 61.2%), fever (5 869 cases, 59.2%) and positive meningeal irritation signs (2 273 cases, 22.9%) were the 3 most common clinical manifestations, followed by nausea and (or) vomiting (2 095 cases, 21.1%), impaired consciousness (2 077 cases, 20.9%), psychiatric symptom (1 866 cases, 18.8%) and epilepsy (1 627 cases, 16.4%), etc., and cranial nerve involvement was found in 669 cases (6.7%). Major pathogens included viruses in 6 814 cases (68.7%), Mycobacterium tuberculosis in 1 677 cases (16.9%), common bacteria in 864 cases (8.7%), fungi in 254 cases (2.6%), spirochetes of syphilis in 183 cases (1.8%), parasites in 121 cases (1.2%), and rickettsiae in 5 cases (0.1%). Urban-rural distribution: slightly more cases were found in the countryside (5 418 cases, 54.6%) than in the towns (4 500 cases, 45.4%). Distribution of onset by season: 2 412 cases (24.3%) fell ill in spring, 2 835 cases (28.6%) in summer, 2 187 cases (22.1%) in fall, and 2 484 cases (25.0%) in winter. Health economics: the duration of hospitalization was 15 (8, 27) days, and the cost of hospitalization was 1.53 (0.91, 3.02)×10 000 yuan. Prognosis: 9 531 cases (96.1%) were cured or improved, and 92 cases (0.9%) died. Conclusions:The pathogens responsible for CNS infectious diseases are predominantly viruses. Although the incidence is slightly higher during the summer months, the overall seasonal pattern is not particularly pronounced. These infections are more commonly observed in young and middle-aged males and present with a diverse range of clinical manifestations, contributing to a significant disease burden.

Objective To investigate the impact of the artificial intelligence iterative reconstruction (AIIR) algorithm on image quality in chest computed tomography (CT) at different radiation doses, and assess its value in reducing radiation dose during chest CT examinations. Methods A simulated chest phantom was scanned with 12 groups of tube voltages and milliampere-seconds, and the radiation dose was recorded for each group. The images of each group were reconstructed using seven methods: AIIR with noise levels 1-5, KARL iterative reconstruction, and filtered back projection (FBP). The CT values and standard deviations of soft tissue, thoracic vertebrae, pulmonary nodules, and the mediastinum were measured, with standard deviation representing image noise. Subjective evaluation of image quality was performed. The Friedman test was used to compare CT values among the seven reconstruction groups, a linear mixed model was employed for statistical analysis of image noise, and the Friedman test was also used for comparing subjective evaluation scores. Results The reconstruction algorithm, tube voltage, milliampere-seconds, and their interactions all showed statistically significant effects on image noise for the four tissues (F = 2.041-391.283, P < 0.05). Among the reconstruction algorithms, noise reduction capability decreased in the following order: AIIR levels 1-5, KARL, and FBP. The interaction between the reconstruction algorithm and tube voltage or milliampere-seconds indicated that AIIR exhibited improved noise reduction efficacy under low tube voltage and low milliampere-second conditions (|t| = 1.892-8.245, P < 0.05). In terms of subjective evaluation of image quality, there was no statistically significant difference among AIIR levels 3-5 (|Z| ≤ 0.567, P > 0.05), and the score of AIIR level 3 was significantly higher than those of AIIR level 1, AIIR level 2, FBP, and KARL level 2 (|Z| = 3.449-5.906, P < 0.05). Conclusion The AIIR reconstruction algorithm significantly reduced image noise in chest CT examinations. For improving image quality while maintaining image realism, AIIR level 3 is recommended, which can reduce the radiation dose by more than 75%. Furthermore, AIIR showed superior performance in noise reduction under low tube voltage and low milliampere-second conditions, demonstrating significant potential for reducing radiation dose.

Objective To compare image quality and clinical usefulness between single breath-hold three-dimensional magnetic resonance cholangiopancreatography with compressed sensing(3D BH-CS-MRCP)and with gradient and spin-echo(3D BH-GRASE-MRCP)and conventional three-dimensional breath-triggered magnetic resonance cholangiopancreatography(3D RT-MRCP).Methods A retrospective analysis was performed in 48 patients(26 males and 22 females,mean age of 53.14±15.19 years),who underwent 3D BH-GRASE-MRCP,3D BH-CS-MRCP and 3D RT-MRCP from September to December 2023.Pancreaticobiliary duct visibility,motion artifacts,background suppression,and overall image quality were scored on a 5-point scale by two radiologists.The relative contrast ratio of three bile duct segmentations(common bile duct,left and right intrahepatic bile ducts)were calculated,and the acquisition time of the three sequences was recorded.Friedman test with a post-hoc test was performed to compare image acquisition time,qualitative and quantitative results.Results The acquisition time was significantly shorter in the two breath-hold groups than for conventional 3D RT-MRCP(P＜0.001).There were no significant differences in overall image quality,motion artifacts,common bile duct and primary branch of intrahepatic bile duct among the three groups.The relative contrast ratio,intrahepatic biliary secondary branch visibility and background suppression score of 3D RT-MRCP and BH-CS-MRCP were significantly higher than those of BH-GRASE-MRCP(P＜0.01).The pancreatic duct(proximal,middle,distal)visibility score of 3D RT-MRCP was significantly better than that of BH-GRASE-MRCP(P=0.002,0.043,0.001),but the gallbladder and gallbladder duct visibility score of BH-GRASE-MRCP was higher than that of 3D RT-MRCP(P=0.036).There was no significant difference between 3D RT-MRCP and BH-CS-MRCP scores except for the middle and distal pancreatic duct visibility.Conclusion Breath-hold 3D MRCP with GRASE and CS can give us feasible options for pancreaticobiliary diagnosis,which significantly shortens the acquisition time without reducing the overall image quality.Compared with BH-GRASE-MRCP,BH-CS-MRCP has better consistency in pancreaticobiliary duct visibility and background suppression.

Objective To investigate the effect of ventilation with different tidal volumes on respiratory mechanics and haemodynamics in children with severe pneumonia.Methods A total of 104 children with severe pneumonia were divided into the control group and the observation group using a random number table method,with 52 cases in each group.Both groups underwent mechanical ventilation treatment.The control group was treated with conventional tidal volume of 10-12 mL/kg,while the observation group was given a low tidal volume of 6-8 mL/kg.The respiratory mechanics indicators,hemodynamic indicators and inflammatory factor indicators before and after treatment were compared between the two groups.Results After treatment,the airway resistance(AR)and airway closing pressure(AOP)were lower in the observation group than those of the control group(P＜0.05),and pulmonary dynamic compliance(Cdyn)was higher in the observation group than that of the control group(P＜0.05).There were no significant differences in heart rate(HR),mean arterial pressure(MAP)and central venous pressure(CVP)after treatment between the two groups(P＜0.05).After treatment,the levels of interleukin(IL)-6,IL-8 and tumor necrosis factor-α(TNF-α)were all lower in the observation group than those in the control group(P＜0.05).Conclusion Small tidal volume mechanical ventilation is effective in improving the respiratory mechanics of children with severe pneumonia without causing large fluctuations in their hemodynamics.At the same time,it can reduce the level of inflammatory factors in the organism.

Objective To compare image quality and clinical usefulness between single breath-hold three-dimensional magnetic resonance cholangiopancreatography with compressed sensing(3D BH-CS-MRCP)and with gradient and spin-echo(3D BH-GRASE-MRCP)and conventional three-dimensional breath-triggered magnetic resonance cholangiopancreatography(3D RT-MRCP).Methods A retrospective analysis was performed in 48 patients(26 males and 22 females,mean age of 53.14±15.19 years),who underwent 3D BH-GRASE-MRCP,3D BH-CS-MRCP and 3D RT-MRCP from September to December 2023.Pancreaticobiliary duct visibility,motion artifacts,background suppression,and overall image quality were scored on a 5-point scale by two radiologists.The relative contrast ratio of three bile duct segmentations(common bile duct,left and right intrahepatic bile ducts)were calculated,and the acquisition time of the three sequences was recorded.Friedman test with a post-hoc test was performed to compare image acquisition time,qualitative and quantitative results.Results The acquisition time was significantly shorter in the two breath-hold groups than for conventional 3D RT-MRCP(P＜0.001).There were no significant differences in overall image quality,motion artifacts,common bile duct and primary branch of intrahepatic bile duct among the three groups.The relative contrast ratio,intrahepatic biliary secondary branch visibility and background suppression score of 3D RT-MRCP and BH-CS-MRCP were significantly higher than those of BH-GRASE-MRCP(P＜0.01).The pancreatic duct(proximal,middle,distal)visibility score of 3D RT-MRCP was significantly better than that of BH-GRASE-MRCP(P=0.002,0.043,0.001),but the gallbladder and gallbladder duct visibility score of BH-GRASE-MRCP was higher than that of 3D RT-MRCP(P=0.036).There was no significant difference between 3D RT-MRCP and BH-CS-MRCP scores except for the middle and distal pancreatic duct visibility.Conclusion Breath-hold 3D MRCP with GRASE and CS can give us feasible options for pancreaticobiliary diagnosis,which significantly shortens the acquisition time without reducing the overall image quality.Compared with BH-GRASE-MRCP,BH-CS-MRCP has better consistency in pancreaticobiliary duct visibility and background suppression.

Objective:To analyze the epidemiological and clinical features of infectious diseases of the central nervous system (CNS).Methods:A cross-sectional study and analysis were conducted to summarize the epidemiological and clinical characteristics of 9 918 patients with CNS infectious diseases, who were diagnosed and treated at 29 hospitals across China from January 1, 2001 to December 31, 2020. Data collected included demographic data, clinical manifestations, health economic indicators, and prognostic outcomes.Results:Among the 9 918 collected cases of CNS infectious diseases, 5 559 were male (56.0%) and 4 359 were female (44.0%), with an onset age of 38 (25, 53) years. Education level: slightly more junior high school education (2 651 cases, 26.7%), and less elementary school education and below (2 181 cases, 22.0%) were found. Occupational distribution: farmers were found predominant (3 215 cases, 32.4%), followed by workers (1 826 cases, 18.4%) and students (1 633 cases, 16.5%). Clinical manifestations: headache (6 074 cases, 61.2%), fever (5 869 cases, 59.2%) and positive meningeal irritation signs (2 273 cases, 22.9%) were the 3 most common clinical manifestations, followed by nausea and (or) vomiting (2 095 cases, 21.1%), impaired consciousness (2 077 cases, 20.9%), psychiatric symptom (1 866 cases, 18.8%) and epilepsy (1 627 cases, 16.4%), etc., and cranial nerve involvement was found in 669 cases (6.7%). Major pathogens included viruses in 6 814 cases (68.7%), Mycobacterium tuberculosis in 1 677 cases (16.9%), common bacteria in 864 cases (8.7%), fungi in 254 cases (2.6%), spirochetes of syphilis in 183 cases (1.8%), parasites in 121 cases (1.2%), and rickettsiae in 5 cases (0.1%). Urban-rural distribution: slightly more cases were found in the countryside (5 418 cases, 54.6%) than in the towns (4 500 cases, 45.4%). Distribution of onset by season: 2 412 cases (24.3%) fell ill in spring, 2 835 cases (28.6%) in summer, 2 187 cases (22.1%) in fall, and 2 484 cases (25.0%) in winter. Health economics: the duration of hospitalization was 15 (8, 27) days, and the cost of hospitalization was 1.53 (0.91, 3.02)×10 000 yuan. Prognosis: 9 531 cases (96.1%) were cured or improved, and 92 cases (0.9%) died. Conclusions:The pathogens responsible for CNS infectious diseases are predominantly viruses. Although the incidence is slightly higher during the summer months, the overall seasonal pattern is not particularly pronounced. These infections are more commonly observed in young and middle-aged males and present with a diverse range of clinical manifestations, contributing to a significant disease burden.

Objective To evaluate the application value of the three-point localization method in improving the quality and efficiency of four-chamber view acquisition in cardiac magnetic resonance(CMR)imaging.Methods A total of 215 patients who underwent four-chamber view in CMR imaging from January 2022 to October 2023 were retrospectively enrolled and divided into two groups.The control group(n=109)received traditional localization method while the study group(n=106)received three-point localization method.The image quality of mitral valve,tricuspid valve and cruciform structure in four-chamber view images were assessed by two radiologists using a Likert 4-piont scale.The time-consumption from scout imaging to the finish of four-chamber view imaging was recorded.Constituent data and numeral data were compared by Chi-square test and two-sample t test,respectively.Kappa test was used to analyze the inter-observer consistency.Results There were no significant inter-group differences in gender,age,disease profile,or the radiographers'experience.The mean quality scores of the mitral valve,tricuspid valve and cruciform structure in the control group and the study group were 3.44±0.64 and 3.63±0.49(P=0.023),3.43±0.67 and 3.53±0.60(P=0.202),3.71±0.49 and 3.83±0.35(P=0.047),respectively.The image quality score was higher in the study group than in the control group,with the differences in mitral valve and cruciform structure reaching statistical significance.The time-consumption for obtaining four-chamber view for the control group and the study group was 11.67±3.49 minutes and 7.212±1.83 minutes,respectively,with statistically significant differences(P＜0.001).Conclusion Compared with the traditional localization method,the three-point localization method provides better image quality in four-chamber view imaging with shortened imaging time.

Objective To evaluate the factors affecting urinary stone detection rate using virtual unenhanced(VUE)images obtained from triphasic dual-energy CT urography(DECTU)based on Logistic regression analysis.Methods For this study,150 patients who had suspected urinary stone and underwent triphasic DECTU were included.The true unenhanced(TUE)images were reconstructed as 120 kVp-like images,and VUE images at the portal venous phase[VUE(VP)]and excretory phase[VUE(EP)]were obtained using iodine removal technique from portal venous and excretory phase DECTU images,respectively.Two readers independently evaluated the above three types of images,and recorded the number of urinary stones,their anatomical locations,and whether there was residual iodine on the VUE images.Stone size and CT number were recorded only on the TUE images.Stone size,CT number,anatomical location,and iodine contrast agent were included in univariate and multivariate Logistic regression analyses to evaluate the factors affecting urinary stone detection rate using VUE images.Thresholds for detecting urinary stones on VUE images were determined using receiver operating characteristics(ROC)analysis.Results We detected 304 stones on TUE images,while the detection rates were 92.4％and 71.4％when using VUE(VP)and VUE(EP)images,respectively.Stone size and CT number were important factors influencing urinary stone detection rate using VUE(VP)and VUE(EP)images(P＜0.01).The area under curve(AUC)of using stone size and CT number for detecting stones using the VUE(VP)images was up to 0.96,and as threshold values,stones with size larger than 3.52 mm and CT number greater than 469 HU were found to have high accuracy.However,the AUC decreased to 0.88 when we combined stone size,CT number and anatomical location using the VUE(EP)images.In addition,different contrast agents did not affect the detection rate of stones on the VUE(EP)images(P=0.57).The stone detection rate in the kidney was significantly lower than those on the VUE(EP)images(P＜0.001).Conclusion VUE(VP)images provide better stone detection.Stone size and CT number have significant impacts on the stone detection rate using VUE images.The lower stone detection rate in the kidney on the VUE(EP)images is related to the residual iodine.