A bacterial effector manipulates plant metabolism, cell death, and immune responses via independent mechanisms.

Bacterial pathogens inject effector proteins inside plant cells to manipulate cellular functions and achieve a successful infection. The soil-borne pathogen Ralstonia solanacearum (Smith), the causal agent of bacterial wilt disease, secretes > 70 different effectors inside plant cells, although only a handful of them have been thoroughly characterized. One of these effectors, named RipI, is required for full R. solanacearum pathogenicity. RipI associates with plant glutamate decarboxylases (GADs) to promote the accumulation of gamma-aminobutyric acid (GABA), which serves as bacterial nutrient. In this work, we found that RipI can also suppress plant immune responses to bacterial elicitors, which seems to be unrelated to the ability of RipI to induce GABA accumulation and plant cell death. A detailed characterization of the RipI features that contribute to its virulence activities identified two residues at the C-terminal domain that mediate RipI interaction with plant GADs and the subsequent promotion of GABA accumulation. These residues are also required for the appropriate homeostasis of RipI in plant cells and the induction of cell death, although they are partially dispensable for the suppression of plant immune responses. Altogether, we decipher and uncouple the virulence activities of an important bacterial effector at the biochemical level.

A bacterial type III effector targets plant vesicle-associated membrane proteins.

The soilborne bacterial pathogen Ralstonia solanacearum is one of the most destructive plant pathogens worldwide, and its infection process involves the manipulation of numerous plant cellular functions. In this work, we found that the R. solanacearum effector protein RipD partially suppressed different levels of plant immunity triggered by R. solanacearum elicitors, including specific responses triggered by pathogen-associated molecular patterns and secreted effectors. RipD localized in different subcellular compartments in plant cells, including vesicles, and its vesicular localization was enriched in cells undergoing R. solanacearum infection, suggesting that this specific localization may be particularly relevant during infection. Among RipD-interacting proteins, we identified plant vesicle-associated membrane proteins (VAMPs). We also found that overexpression of Arabidopsis thaliana VAMP721 and VAMP722 in Nicotiana benthamiana leaves promoted resistance to R. solanacearum, and this was abolished by the simultaneous expression of RipD, suggesting that RipD targets VAMPs to contribute to R. solanacearum virulence. Among proteins secreted in VAMP721/722-containing vesicles, CCOAOMT1 is an enzyme required for lignin biosynthesis, and mutation of CCOAOMT1 enhanced plant susceptibility to R. solanacearum. Altogether our results reveal the contribution of VAMPs to plant resistance against R. solanacearum and their targeting by a bacterial effector as a pathogen virulence strategy.

Predictive Value of Exercise Blood Pressure Changes for Orthostatic Hypotension in Patients With Parkinson’s Disease

Background@#and Purpose Orthostatic hypotension (OH) is common in patients with Parkinson’s disease (PD). Early recognition OH is required with sensitive assessments. The purpose of this study was to determine whether blood pressure (BP) changes during exercise can predict the occurrence of OH in PD. @*Methods@#This prospective cohort study included 80 consecutive patients with PD. All patients agreed to participate in a baseline evaluation and cardiopulmonary exercise test (CPET).According to the initial active standing test (AST), those without OH (PD-nonOH) at baseline had their AST results followed up for 6 months. The main outcome was defined as whether patients without OH at baseline would develop OH after 6 months. Logistic regression analysis was applied to identify the relevant variables. A nomogram was constructed based on clinical features and identified variables. The concordance index (C-index) and area under the receiver operating characteristic curve (AUC) were used to evaluate the accuracy and predictive ability of the nomogram, respectively. @*Results@#CPET results indicated that peak load, peak heart rate, heart rate recovery at 1 min, and systolic BP change (ΔSBP) were lower in those with OH than in the PD-nonOH group (p<0.05) at baseline. Logistic regression analysis indicated that peak load and ΔSBP during CPET had significant effects on OH (p<0.05). Age, sex, peak load, and ΔSBP were used to construct the nomogram model (C-index=0.761). The prediction model had an AUC of 0.782 (95% confidence interval=0.649–0.889) and a specificity and sensitivity of 70.0% and 81.8%, respectively. @*Conclusions@#This study has identified predictive factors for OH development in patients with PD. CPET could be used as a complementary examination to identify patients at a high risk of OH.

Genotype and Phenotype of α-Thalassemia Fusion Gene in Huadu District of Guangzhou, Guangdong Province of China / 中国实验血液学杂志

OBJECTIVE@#To explore the carrier rate, genotype and phenotype of α-thalassemia fusion gene in Huadu district of Guangzhou, Guangdong province of China, and provide data reference for the prevention and control of thalassemia.@*METHODS@#A total of 10 769 samples who were screened for thalassemia in Maternal and Child Health Hospital of Huadu District from July 2019 to November 2020 were analyzed retrospectively. Blood cell analysis and hemoglobin (Hb) electrophoresis were performed. Thalassemia genes were analyzed by gap-PCR and PCR-reverse dot blot hybridization (PCR-RDB).@*RESULTS@#A total of 9 cases with α-thalassemia fusion gene were detected in 10 769 samples (0.08%). There were 7 cases with fusion gene heterozygote, 1 case with compound of α-thalassemia fusion gene and Hb G-Honolulu, 1 case with compound of α-thalassemia fusion gene and Hb QS. The MCV results of 4 samples of blood cell analysis were within the reference range, the Hb A2 value of 1 case was decreased, and there were no other abnormalities found.@*CONCLUSION@#The α-thalassemia fusion gene is common in Huadu district of Guangzhou, and heterozygotes are more common, and current screening methods easily lead to misdiagnosis.

Combined micro-apical surgery and vital pulp therapy in mandibular second molars with external root resorption caused by impacted teeth / 华西口腔医学杂志

OBJECTIVES@#This study aimed to establish a new treatment of the mandibular second molars with external root resorption caused by impacted teeth to preserve the affected teeth and their vital pulps.@*METHODS@#For mandibular second molars clinically diagnosed as external root resorption caused by impacted teeth, debridement and removal of the root at the resorption site via micro-apical surgery and direct capping of the pulp with bioactive material on the surface of the root amputation via vital pulp therapy were performed immediately after the impacted teeth were extracted.@*RESULTS@#The external root resorption of the affected tooth was ceased. It was asymptomatic with intact crown, normal pulp, periapical alveolar bone reconstruction, normal periodontal ligament, continuous bone sclerosis, and no periapical translucency in radiographic examination at the 1-year postoperative follow-up, thus showing good prognosis.@*CONCLUSIONS@#Simultaneous combination of micro-apical surgery and vital pulp therapy after extraction of impacted teeth could successfully preserve mandibular second molars with ERR caused by impacted teeth and their vital pulps.

Effect of dental follicles in minimally invasive open-eruption technique of labially impacted maxillary central incisors / 华西口腔医学杂志

OBJECTIVES@#To summarize the open-eruption technique of impacted anterior maxillary teeth, this study reports a technically improved operation on surgical exposure based on dental follicles and evaluates post-treatment periodontal health considering the effect of dental follicles.@*METHODS@#Patients who underwent open-eruption technique with unilateral labially impacted maxillary central incisors were selected. The impacted teeth were assigned to the experimental group, and the contralateral unimpacted maxillary central incisors were assigned to the control group. In the surgical exposure, the new technique makes use of dental follicles to manage the soft tissue, so as to preserve soft tissue for better aesthetic results and healthier periodontal tissue. Tooth length, root length, alveolar bone loss, and alveolar bone thickness were recorded after the therapy.@*RESULTS@#A total of 17 patients with unilateral maxillary central incisor impaction were successfully treated. The tooth length and root length of the two groups showed a statistically significant difference between the impacted and homonym teeth, with a shorter length in the impacted tooth (P<0.05). More labial alveolar bone loss was found in the experimental group compared with that in the control group (P<0.05). The outcomes of the cementoenamel junction width, pa- latal alveolar bone loss, and alveolar bone thickness did not indicate statistical significance between the experimental and control groups (P>0.05).@*CONCLUSIONS@#In the surgical exposure, the new technique uses dental follicles to manage the soft tissue and preserve it for better aesthetic results and healthier periodontal tissues.

The impact of LDL-C/HDL-C ratio on severity of coronary artery disease and 2-year outcome in patients with premature coronary heart disease: results of a prospective, multicenter, observational cohort study / 中华心血管病杂志

Objective: To explore the relationship between low density lipoprotein cholesterol (LDL-C)/high density lipoprotein cholesterol (HDL-C) ratio with the severity of coronary artery disease and 2-yeat outcome in patients with premature coronary heart disease. Methods: This prospective, multicenter, observational cohort study is originated from the PROMISE study. Eighteen thousand seven hundred and one patients with coronary heart disease (CHD) were screened from January 2015 to May 2019. Three thousand eight hundred and sixty-one patients with premature CHD were enrolled in the current study. According to the median LDL-C/HDL-C ratio (2.4), the patients were divided into two groups: low LDL-C/HDL-C group (LDL-C/HDL-C≤2.4, n=1 867) and high LDL-C/HDL-C group (LDL-C/HDL-C>2.4, n=1 994). Baseline data and 2-year major adverse cardiovascular and cerebrovascular events (MACCE) were collected and analyzed in order to find the differences between premature CHD patients at different LDL-C/HDL-C levels, and explore the correlation between LDL-C/HDL-C ratio with the severity of coronary artery disease and MACCE. Results: The average age of the low LDL-C/HDL-C ratio group was (48.5±6.5) years, 1 154 patients were males (61.8%); the average age of high LDL-C/HDL-C ratio group was (46.5±6.8) years, 1 523 were males (76.4%). The number of target lesions, the number of coronary artery lesions, the preoperative SNYTAX score and the proportion of three-vessel coronary artery disease in the high LDL-C/HDL-C group were significantly higher than those in the low LDL-C/HDL-C group (1.04±0.74 vs. 0.97±0.80, P=0.002; 2.04±0.84 vs. 1.85±0.84, P<0.001; 13.81±8.87 vs. 11.70±8.05, P<0.001; 36.2% vs. 27.4%, respectively, P<0.001). Correlation analysis showed that there was a significant positive correlation between LDL-C/HDL-C ratio and preoperative SYNTAX score, the number of coronary artery lesions, the number of target lesions and whether it was a three-vessel coronary artery disease (all P<0.05). The 2-year follow-up results showed that the incidence of MACCE was significantly higher in the high LDL-C/HDL-C group than that in the low LDL-C/HDL-C group (6.9% vs. 9.1%, P=0.011). There was no significant difference in the incidence of all-cause death, cardiac death, myocardial infarction, stroke, revascularization and bleeding between the two groups. Cox multivariate regression analysis showed that the LDL-C/HDL-C ratio has no correlation with 2-year MACCE, death, myocardial infarction, revascularization, stroke and bleeding events above BARC2 in patients with premature CHD. Conclusion: High LDL-C/HDL-C ratio is positively correlated with the severity of coronary artery disease in patients with premature CHD. The incidence of MACCE of patients with high LDL-C/HDL-C ratio is significantly higher during 2 years follow-up; LDL-C/HDL-C ratio may be an indicator for evaluating the severity of coronary artery disease and long-term prognosis in patients with premature CHD.

Association between maternal gestational diabetes mellitus and the risk of autism spectrum disorder in offspring / 中国当代儿科杂志

OBJECTIVES@#To explore the association between maternal gestational diabetes mellitus (GDM) exposure and the development of autism spectrum disorder (ASD) in offspring.@*METHODS@#A case-control study was conducted, recruiting 221 children with ASD and 400 healthy children as controls. Questionnaires and interviews were used to collect information on general characteristics of the children, socio-economic characteristics of the family, maternal pregnancy history, and maternal disease exposure during pregnancy. Multivariate logistic regression analysis was used to investigate the association between maternal GDM exposure and the development of ASD in offspring. The potential interaction between offspring gender and maternal GDM exposure on the development of ASD in offspring was explored.@*RESULTS@#The proportion of maternal GDM was significantly higher in the ASD group compared to the control group (16.3% vs 9.4%, P=0.014). After adjusting for variables such as gender, gestational age, mode of delivery, parity, and maternal education level, maternal GDM exposure was a risk factor for ASD in offspring (OR=2.18, 95%CI: 1.04-4.54, P=0.038). On the basis of adjusting the above variables, after further adjusting the variables including prenatal intake of multivitamins, folic acid intake in the first three months of pregnancy, and assisted reproduction the result trend did not change, but no statistical significance was observed (OR=1.94, 95%CI: 0.74-5.11, P=0.183). There was an interaction between maternal GDM exposure and offspring gender on the development of ASD in offspring (P<0.001). Gender stratified analysis showed that only in male offspring of mothers with GDM, the risk of ASD was significantly increased (OR=3.67, 95%CI: 1.16-11.65, P=0.027).@*CONCLUSIONS@#Maternal GDM exposure might increase the risk of ASD in offspring. There is an interaction between GDM exposure and offspring gender in the development of ASD in offspring.

Exploring the protective mechanism of Tibetan medicine Potentilla anserine on cyclophosphamide-induced myelosuppression based on metabonomics technology / 药学学报

The study aims to explore the effects and mechanisms of water extract of Potentilla anserina (PA) on myelosuppression mice induced by cyclophosphamide based on metabonomics. The myelosuppressive mouse model was established by injected with cyclophosphamide and treated with water extract of PA. Thymus and spleen indexes, peripheral hemogram and bone marrow nucleated cells of each group was detected. Bone marrow pathology analysis was performed by hematoxylin-eosin staining. The levels of interleukin 3 (IL-3), interleukin 6 (IL-6), erythropoietin (EPO), granulocyte colony stimulating factor (GM-CSF), malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) in serum were measured. The changes of biomarkers and related metabolic pathways were analyzed by UPLC-Q-TOF/MS-based metabonomics. Animal experiments were approved by the Animal Ethics Committee of Southwest Minzu University. The high doses of PA could significantly improve the decrease of white blood cell (WBC), red blood cell (RBC) counts and hemoglobin (HGB) levels of mice induced by cyclophosphamide (P < 0.05), and significantly increase the number of nucleated cells and the area of hematopoietic tissue in femoral bone marrow. The medium and high doses of PA could significantly improve the serum levels of SOD, CAT, MDA, IL-6 and GM-CSF (P < 0.05), and have no significant effect on the expression of IL-3 and EPO (P > 0.05). Serum metabolomics analysis showed that the aqueous extracts of PA could alleviate myrosuppression by regulating the aminoacyl-tRNA, valine, leucine and isoleucine biosynthesis mediated by 13 different metabolites such as valine, leucine, asparagine and hydroxyisohexic acid. PA improve the inhibition of hematopoietic function in myelosuppression mouse, and its mechanisms may be related to anti-oxidation and promoting the expression of hematopoietic-related cytokines and regulating the related metabolic pathways.

Prognosis of patients planned and unplanned admission to the intensive care unit after surgery: a comparative study / 中华危重病急救医学

OBJECTIVE@#To compare and analyze the effect of unplanned versus planned admission to the intensive care unit (ICU) on the prognosis of high-risk patients after surgery, so as to provide a clinical evidence for clinical medical staff to evaluate whether the postoperative patients should be transferred to ICU or not after surgery.@*METHODS@#The clinical data of patients who were transferred to ICU after surgery admitted to the Affiliated Hospital of Guizhou Medical University from January to December in 2021 were retrospectively analyzed, including gender, age, body mass index, past history (whether combined with hypertension, diabetes, pulmonary disease, cardiac disease, renal failure, liver failure, hematologic disorders, tumor, etc.), acute physiology and chronic health evaluation II (APACHE II), elective surgery, pre-operative hospital consultation, length of surgery, worst value of laboratory parameters within 24 hours of ICU admission, need for invasive mechanical ventilation (IMV), duration of IMV, length of ICU stay, total length of hospital stay, ICU mortality, in-hospital mortality, and survival status at 30th day postoperative. The unplanned patients were further divided into the immediate transfer group and delayed transfer group according to the timing of their ICU entrance after surgery, and the prognosis was compared between the two groups. Cox regression analysis was used to find the independent risk factors of 30-day mortality in patients transferred to ICU after surgery.@*RESULTS@#Finally, 377 patients were included in the post-operative admission to the ICU, including 232 in the planned transfer group and 145 in the unplanned transfer group (42 immediate transfers and 103 delayed transfers). Compared to the planned transfer group, patients in the unplanned transfer group had higher peripheral blood white blood cell count (WBC) at the time of transfer to the ICU [×109/L: 10.86 (7.09, 16.68) vs. 10.11 (6.56, 13.27)], longer total length of hospital stay [days: 23.00 (14.00, 34.00) vs. 19.00 (12.00, 29.00)], and 30-day post-operative mortality was higher [29.66% (43/145) vs. 17.24% (40/232)], but haemoglobin (Hb), arterial partial pressure of carbon dioxide (PaCO2), oxygenation index (PaO2/FiO2), and IMV requirement rate were lower [Hb (g/L): 95.00 (78.00, 113.50) vs. 98.00 (85.00, 123.00), PaCO2 (mmHg, 1 mmHg ≈ 0.133 kPa): 36.00 (29.00, 41.50) vs. 39.00 (33.00, 43.00), PaO2/FiO2 (mmHg): 197.00 (137.50, 283.50) vs. 238.00 (178.00, 350.25), IMV requirement rate: 82.76% (120/145) vs. 93.97% (218/232)], all differences were statistically significant (all P < 0.05). Kaplan-Meier survival curve showed that the 30-day cumulative survival rate after surgery was significantly lower in the unplanned transfer group than in the planned transfer group (Log-Rank test: χ2 = 7.659, P = 0.006). Univariate Cox regression analysis showed that unplanned transfer, APACHE II score, whether deeded IMV at transfer, total length of hospital stay, WBC, blood K+, and blood lactic acid (Lac) were associated with 30-day mortality after operation (all P < 0.05). Multifactorial Cox analysis showed that unplanned transfer [hazard ratio (HR) = 2.45, 95% confidence interval (95%CI) was 1.54-3.89, P < 0.001], APACHE II score (HR = 1.03, 95%CI was 1.00-1.07, P = 0.031), the total length of hospital stay (HR = 0.86, 95%CI was 0.83-0.89, P < 0.001), the need for IMV on admission (HR = 4.31, 95%CI was 1.27-14.63, P = 0.019), highest Lac value within 24 hours of transfer to the ICU (HR = 1.17, 95%CI was 1.10-1.24, P < 0.001), and tumor history (HR = 3.12, 95%CI was 1.36-7.13, P = 0.007) were independent risk factors for patient death at 30 days post-operative, and the risk of death was 2.45 times higher in patients unplanned transferred than in those planned transferred. Subgroup analysis showed that patients in the delayed transfer group had significantly longer IMV times than those in the immediate transfer group [hours: 43.00 (11.00, 121.00) vs. 17.50 (2.75, 73.00), P < 0.05].@*CONCLUSIONS@#The 30-day mortality, WBC and total length of hospital stay were higher in patients who were transferred to ICU after surgery, and PaO2/FiO2 was lower. Unplanned transfer, oncology history, use of IMV, APACHE II score, total length of hospital stay, and Lac were independent risk factors for patient death at 30 days postoperatively, and patients with delayed transfer to ICU had longer IMV time.

miR-144 negatively regulates the effect of CCNB1 protein on the biological behavior of hepatoma cells.

Liver cancer poses a great threat to the life safety of patients, which is a common malignant tumor worldwide. This study aims to explore the effect of miR-144 negatively regulating CCNB1 on the biological behavior of liver cancer cells, including the proliferation, apoptosis and migration of liver cancer cells, so as to provide a sufficient biological basis for the treatment of liver cancer. A 3 armour hospital at the records of 100 patients with liver cancer in 2015-2019 as the research object, and resection of the liver cancer cells and tissue adjacent to carcinoma as the research samples, using polymerase chain reaction (PCR) for the organization of miR-144 gene and detect CCNB1 protein expression level, and by using a technique called RNA interference to silence the CCNB1 gene, and try to transfer by transfection CCNB1 protein, thus all kinds of biological behaviour of hepatocellular carcinoma cells. The liver tissue of miR-144 is low, the level of gene expression CCNB1 protein expression level is higher, the expression level in liver cancer cells directly influences the curative effect of hepatocellular carcinoma patients, the miR-144 gene can negative regulation CCNB1 protein, through this kind of negative adjustment to the biological behavior of liver cancer cells have a profound impact.

Correlation between intraplaque hemorrhage and new-onset embolic cerebral infarction after basilar artery angioplasty or stenting / 国际脑血管病杂志

Objective:To investigate the correlation between intraplaque hemorrhage (IPH) and new-onset embolic cerebral infarction after basilar artery angioplasty or stenting.Methods:Consecutive patients with severe basilar atherosclerotic stenosis underwent basilar artery angioplasty or stenting in the Department of Neurology, Guangdong Provincial Hospital of Chinese Medicine from January 2015 to February 2022 were retrospectively enrolled. High resolution magnetic resonance vessel wall imaging (HRMR-VWI) and diffusion-weighted imaging (DWI) were performed within one week before procedure, and brain DWI or CT examination was performed within 72 h after procedure to determine the patients with new-onset embolic cerebral infarction.Results:A total of 32 patients were enrolled in the analyze. IPH existed in 10 patients with basilar artery culprit plaque, and 5 had new-onset embolic cerebral infarction after procedure. The incidence of embolic cerebral infarction in the IPH group was significantly higher than that in the non-IPH group (50% vs. 0%; P=0.001). The proportion of patients with IPH in the embolic cerebral infarction group was significantly higher than that in the non-embolic cerebral infarction group (100% vs. 18.5%; P=0.001). Conclusion:IPH may be associated with new-onset embolic cerebral infarction after basilar artery angioplasty or stenting.

Intervention effect of job rotation on wrist work-related musculoskeletal disorders of physical therapists / 中国职业医学

@#Objective - （ ） To evaluate the effect of job rotation on pain in wrist work related musculoskeletal disorders WMSDs （ ）Methods of physical therapists PTs . A total of 100 PTs from nine medical institutions were selected as the research subjects ， using judgment sampling method and they were divided into control group and intervention group by stratified random sampling ， method with 50 person in each group. The individuals in control group perform routine works. People in the intervention group were rotated between posts or added mobile shift replacements in daily work for 30 minutes. The duration of intervention was ， ， （ ） once a day five days a week for ten weeks. Visual Analogue Scale VAS score and pain duration were used as the evaluation ， indexes of intervention effect. The changes of indexes before intervention five weeks and ten weeks after intervention were Results ， compared between the two groups. Before intervention there was no significant difference in the VAS score and pain （ P ） duration between the control group and the intervention group all >0.05 . There was no significant difference in VAS score （ P ） and pain duration among the control group at three time points after intervention all >0.05 . The VAS score of PTs in the （P ）， intervention group at ten weeks was lower than that in the control group at the same time point <0.05 and it was lower than （ P ） that before intervention and at five weeks of intervention in the same group all <0.05 . The pain duration of PTs in the （ P ）， intervention group was lower than that in the control group at five and ten weeks after intervention all <0.05 and was lower （ P ） Conclusion ， than that before intervention at the same group all <0.05 . Rotating schedule can relieve WMSDs of PTs and the effect of intervention for ten weeks is more effective than that of intervention for five weeks.

Genomic and transcriptomic analysis unveils population evolution and development of pesticide resistance in fall armyworm Spodoptera frugiperda

The fall armyworm (FAW), Spodoptera frugiperda, is a destructive pest native to America and has recently become an invasive insect pest in China. Because of its rapid spread and great risks in China, understanding of FAW genetic background and pesticide resistance is urgent and essential to develop effective management strategies. Here, we assembled a chromosome-level genome of a male FAW (SFynMstLFR) and compared re-sequencing results of the populations from America, Africa, and China. Strain identification of 163 individuals collected from America, Africa and China showed that both C and R strains were found in the American populations, while only C strain was found in the Chinese and African populations. Moreover, population genomics analysis showed that populations from Africa and China have close relationship with significantly genetic differentiation from American populations. Taken together, FAWs invaded into China were most likely originated from Africa. Comparative genomics analysis displayed that the cytochrome p450 gene family is extremely expanded to 425 members in FAW, of which 283 genes are specific to FAW. Treatments of Chinese populations with twenty-three pesticides showed the variant patterns of transcriptome profiles, and several detoxification genes such as AOX, UGT and GST specially responded to the pesticides. These findings will be useful in developing effective strategies for management of FAW in China and other invaded areas.

The GABA transaminase GabT is required for full virulence of Ralstonia solanacearum in tomato.

The utilization of plant gamma-aminobutyric acid (GABA) is essential for the pathogenicity of the bacterial plant pathogen Ralstonia solanacearum. A knockout mutant in the GABA transaminase-encoding gene gabT is unable to utilize GABA as a nutrient and its ability to cause disease in plants is strongly compromised. However, the proximity of the gabD gene (encoding a succinate semialdehyde dehydrogenase) in the same operon raises the question of whether an impact on the gabD gene underlies or contributes to the virulence attenuation of the ΔgabT mutant. In this work, we use genetic complementation to show that the expression of the gabT gene is able to rescue the impaired virulence of the ΔgabT knockout mutant in tomato plants, confirming that the gabT-encoded GABA transaminase is indeed required for full virulence of R. solanacearum in a natural host plant.

Enhancing nitrate and phosphorus removal from stormwater in a fold-flow bioretention system with saturated zones.

The traditional bioretention systems possess a remarkably low nitrogen and phosphorus removal effect. The removal rate fluctuates greatly, and even appears as negative removal of nitrogen and phosphorus. Four simulated bioretention experimental columns with different bilayer media, packing composition and structure were constructed. Based on the traditional fillers, the modified composite fillers with hydroxy-aluminum and modified vermiculite sludge particle (HAVSP) were added. The traditional filler (C1) and the modified composite filler (C2) were added respectively, moreover saturated zones were set up to enhance the effect of nitrogen and phosphorus removal. Removal of nutrients from experimental columns by simulated runoff efficiency was evaluated and compared. In addition, the effect of media depth on phosphorus retention and denitrifying enzyme activity in bioretention columns was also evaluated. The experimental column #2 filled with C2 had the optimum removal effect on TP (93.70%), however, the removal effect of TP by filling C1 experimental columns was insufficient (57.36%). Designed to remove nitrate (NO3--N) and total nitrogen, the experimental column #4 showed the best performance (83.54% and 92.15%, respectively). In this study, we propose a fold-flow bioretention system by filling HAVSP in combination with saturated zones. The runoff water quality can be effectively improved, and a new bioretention cell configuration can be provided for efficient stormwater treatment.

Tomato Stem Injection for the Precise Assessment of Ralstonia solanacearum Fitness in Planta.

Ralstonia solanacearum is a soil-borne pathogen with worldwide distribution that causes bacterial wilt disease in more than 250 plant species. R. solanacearum invades plants through the roots, reaches the vascular system, and colonizes the whole plant by moving through the xylem, where it eventually replicates rapidly, causing plant death. Usual assays to measure the virulence of R. solanacearum under laboratory conditions rely on soil-drenching inoculation followed by observation and scoring of disease symptoms. Here, we describe a protocol to assess the replication of R. solanacearum following injection into tomato stems. This protocol includes four major steps: 1) growth of tomato plants; 2) R. solanacearum injection into tomato stems; 3) collection of tomato xylem samples and bacterial quantitation; and 4) data analysis and representation. This method bypasses the natural penetration process of the pathogen, thus minimizing variation associated with stochastic events during bacterial invasion, and provides a sensitive and accurate measurement of bacterial fitness inside xylem vessels.

SGT1 is not required for plant LRR-RLK-mediated immunity.

Plant immune signalling activated by the perception of pathogen-associated molecular patterns (PAMPs) or effector proteins is mediated by pattern-recognition receptors (PRRs) and nucleotide-binding and leucine-rich repeat domain-containing receptors (NLRs), which often share cellular components and downstream responses. Many PRRs are leucine-rich repeat receptor-like kinases (LRR-RLKs), which mostly perceive proteinaceous PAMPs. The suppressor of the G2 allele of skp1 (SGT1) is a core immune regulator required for the activation of NLR-mediated immunity. In this work, we examined the requirement of SGT1 for immune responses mediated by several LRR-RLKs in both Nicotiana benthamiana and Arabidopsis. Using complementary genetic approaches, we found that SGT1 is not limiting for early PRR-dependent responses or antibacterial immunity. We therefore conclude that SGT1 does not play a significant role in bacterial PAMP-triggered immunity.

PCNA Confers the Conversion of Hepatitis B Virus Relaxed Circular DNA to Covalently Closed Circular DNA by Its DNA Binding Domain / 中国生物化学与分子生物学报

Chronic hepatitis B virus (HBV) infection is a primary cause for liver cancer. And the main challenge of curing hepatitis B is the elimination of the stable covalently closed circular DNA (cccDNA) of the viral genome. The formation of HBV cccDNA requires the filling of single-stranded region and the ligation of nicks in relaxed circular DNA (rcDNA) strands. Previously, our group reported that proliferating cell nuclear antigen (PCNA) was involved in the formation of HBV cccDNA. However, the underlying mechanism of the conversion of HBV rcDNA to cccDNA is poorly understood. In the present study, we aim to explore the mechanism by which PCNA contributes to the conversion of HBV rcDNA to cccDNA. Our data showed that PCNA was involved in the process of HBV rcDNA repair. The knockout of PCNA by the CRISPR/Cas9 system remarkably blocked the conversion of HBV rcDNA to cccDNA, while the ectopic expression of PCNA could effectively rescue the event (P<0. 001). Knockout of PCNA significantly slowed down the conversion kinetics of HBV rcDNA to cccDNA (P<0. 01). Mechanically, the DNA binding domain of PCNA was required for the process of HBV rcDNA repair to cccDNA (P<0. 01). Thus, we conclude that PCNA confers the conversion of HBV rcDNA to cccDNA by its DNA binding domain. Clinically, PCNA might serve as a novel target for antiviral therapy.

Slug Inhibits Proliferation of Cervical Cancer Cells Through Down-regulating CDH3/β-catenin/C-myc Expression / 肿瘤防治研究

Objective To investigate the related mechanism of Slug inhibiting the proliferation of cervical cancer cell through CDH3/β-catenin/C-myc. Methods SiHa cells with stable Slug expression were screened. The expression of CDH3 in Slug-overexpressed SiHa cell was detected by RNA-sequence, Real-time PCR, Western blot and immunocytochemistry. The expression of CDH3 in SiHa and HeLa cells were detected by Western blot and immunocytochemistry. The protein level of CDH3 was up-regulated in HeLa cells or rescued in SiHa-Slug cells by transient transfection of CDH3 expression vector. The protein levels of β-catenin and C-myc were detected by Western blot, the cell growth was detected by cell counting and CCK-8 assays. Luciferase reporter assay and chromatin immunoprecipitation assay (ChIP) were performed to detect the effect of Slug on regulating the promoter region of CDH3. Results SiHa cell line with stable Slug expression was successfully constructed. Slug overexpression inhibited CDH3 expression in SiHa cells. CDH3 promoted cell proliferation and up-regulated the protein level of β-catenin and C-myc in HeLa and SiHa-Slug cells. Slug could recognize and bind to the E-boxes in the CDH3 promoter region and inhibited the transcription of CDH3 in SiHa cells. Conclusion Slug could inhibit the expression of β-catenin and C-myc by inhibiting CDH3 transcription in SiHa cells, and then attenuate the growth of SiHa cells.