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161.
Agrobacterium VirD2 protein interacts with plant host cyclophilins   总被引:7,自引:0,他引:7       下载免费PDF全文
Agrobacterium tumefaciens induces crown gall tumors on plants by transferring a nucleoprotein complex, the T-complex, from the bacterium to the plant cell. The T-complex consists of T-DNA, a single-stranded DNA segment of the tumor-inducing plasmid, VirD2, an endonuclease covalently bound to the 5′ end of the T-DNA, and perhaps VirE2, a single-stranded DNA binding protein. The yeast two-hybrid system was used to screen for proteins interacting with VirD2 and VirE2 to identify components in Arabidopsis thaliana that interact with the T-complex. Three VirD2- and two VirE2-interacting proteins were identified. Here we characterize the interactions of VirD2 with two isoforms of Arabidopsis cyclophilins identified by using this analysis. The VirD2 domain interacting with the cyclophilins is distinct from the endonuclease, omega, and the nuclear localization signal domains. The VirD2–cyclophilin interaction is disrupted in vitro by cyclosporin A, which also inhibits Agrobacterium-mediated transformation of Arabidopsis and tobacco. These data strongly suggest that host cyclophilins play a role in T-DNA transfer.  相似文献   
162.

Background and objectives

Treatment of congenital nephrotic syndrome (CNS) and steroid–resistant nephrotic syndrome (SRNS) is demanding, and renal prognosis is poor. Numerous causative gene mutations have been identified in SRNS that affect the renal podocyte. In the era of high–throughput sequencing techniques, patients with nongenetic SRNS frequently escape the scientific interest. We here present the long-term data of the German CNS/SRNS Follow-Up Study, focusing on the response to cyclosporin A (CsA) in patients with nongenetic versus genetic disease.

Design, setting, participants, & measurements

Cross–sectional and longitudinal clinical data were collected from 231 patients with CNS/SRNS treated at eight university pediatric nephrology units with a median observation time of 113 months (interquartile range, 50–178). Genotyping was performed systematically in all patients.

Results

The overall mutation detection rate was high at 57% (97% in CNS and 41% in SRNS); 85% of all mutations were identified by the analysis of three single genes only (NPHS1, NPHS2, and WT1), accounting for 92% of all mutations in patients with CNS and 79% of all mutations in patients with SRNS. Remission of the disease in nongenetic SRNS was observed in 78% of patients after a median treatment period of 2.5 months; 82% of nongenetic patients responded within 6 months of therapy, and 98% of patients with nongenetic SRNS and CsA–induced complete remission (normalbuminemia and no proteinuria) maintained a normal renal function. Genetic SRNS, on the contrary, is associated with a high rate of ESRD in 66% of patients. Only 3% of patients with genetic SRNS experienced a complete remission and 16% of patients with genetic SRNS experienced a partial remission after CsA therapy.

Conclusions

The efficacy of CsA is high in nonhereditary SRNS, with an excellent prognosis of renal function in the large majority of patients. CsA should be given for a minimum period of 6 months in these patients with nongenetic SRNS. In genetic SRNS, response to CsA was low and restricted to exceptional patients.  相似文献   
163.
OBJECTIVE: Preeclampsia is a serious complication in pregnancy with an increased future cardiovascular risk for both mother and newborn. Recently, low levels of endogenous soluble receptor for advanced glycation endproducts (esRAGE) have been associated with increased cardiovascular risk. In the current study, we investigated esRAGE serum levels in patients with preeclampsia as compared to healthy gestational age-matched controls. METHODS: esRAGE was quantified by enzyme-linked immunosorbent assay in controls and patients with preeclampsia during pregnancy (control: n = 20, preeclampsia: n = 16) and 6 months after delivery (control: n = 19, preeclampsia: n = 15). Furthermore, esRAGE was correlated to clinical and biochemical measures of renal function, glucose and lipid metabolism, as well as inflammation. RESULTS: During pregnancy, median maternal serum esRAGE concentrations were more than three-fold higher in patients with preeclampsia (200 ng/l) than in controls (63 ng/l) (P < 0.01). Furthermore, esRAGE levels positively correlated with age, blood pressure, creatinine, adiponectin, and C-reactive protein, whereas a negative correlation existed with fasting insulin and the homeostasis model assessment of insulin resistance index. In multivariate analyses, homeostasis model assessment of insulin resistance and C-reactive protein independently predicted esRAGE serum levels and explained 44% of the variation in esRAGE concentrations. Surprisingly, median esRAGE concentrations 6 months after delivery were significantly lower in former patients with preeclampsia (270 ng/l) than in controls (342 ng/l) in contrast to the results obtained during pregnancy. CONCLUSION: We showed that maternal esRAGE concentrations are significantly increased in patients with preeclampsia during pregnancy. Here, insulin sensitivity and inflammatory status independently predict serum esRAGE levels.  相似文献   
164.
165.
The aim of this study was to assess the impact of ciprofloxacin, clindamycin, and placebo administration on culturable Gram-negative isolates and the antibiotic resistance genes they harbor. Saliva and fecal samples were collected from healthy human volunteers before and at intervals, up to 1 year after antibiotic administration. Samples were plated on selective and nonselective media to monitor changes in different colony types or bacterial species. Following ciprofloxacin administration, there was a decrease of Escherichia coli in feces and after clindamycin administration a decrease of Bacteroides in feces and Leptotrichia in saliva, which all returned to pretreatment levels within 1 to 4 months. Ciprofloxacin administration also resulted in an increase in ciprofloxacin-resistant Veillonella in saliva, which persisted for 12 months. Additionally, 949 aerobic and anaerobic isolates purified from ciprofloxacin- and clindamycin-containing plates were screened for the presence of resistance genes. Resistance gene carriage was widespread in isolates from all three treatment groups, and no association was observed between genes and antibiotic administration. Although the anaerobic component of the microbiota was not a major reservoir of aerobe-associated antimicrobial resistance (AMR) genes, we detected the sulfonamide resistance gene sul2 in anaerobic isolates. The longitudinal nature of the study allowed identification of distinct Escherichia coli clones harboring multiple resistance genes, including one carrying an extended-spectrum β-lactamase blaCTX-M group 9 gene, which persisted in the gut for up to 4 months. This study provided insight into the effects of antibiotic administration on healthy microbiota and the diversity of resistance genes harbored therein.  相似文献   
166.
We evaluated the monthly distribution of rotavirus diarrhea in a cohort of children 12–24 months of age followed as part of a diarrhea clinical trial in a peri-urban community of Lima. We observed a peak of rotavirus diarrhea in the winter months and a decrease in rotavirus prevalence after the introduction of the rotavirus vaccine in Peru.  相似文献   
167.
The prevention of hospital acquired pressure ulcers in critically ill patients remains a significant clinical challenge. The aim of this trial was to investigate the effectiveness of multi‐layered soft silicone foam dressings in preventing intensive care unit (ICU) pressure ulcers when applied in the emergency department to 440 trauma and critically ill patients. Intervention group patients (n = 219) had Mepilex® Border Sacrum and Mepilex® Heel dressings applied in the emergency department and maintained throughout their ICU stay. Results revealed that there were significantly fewer patients with pressure ulcers in the intervention group compared to the control group (5 versus 20, P = 0·001). This represented a 10% difference in incidence between the groups (3·1% versus 13·1%) and a number needed to treat of ten patients to prevent one pressure ulcer. Overall there were fewer sacral (2 versus 8, P = 0·05) and heel pressure ulcers (5 versus 19, P = 0·002) and pressure injuries overall (7 versus 27, P = 0·002) in interventions than in controls. The time to injury survival analysis indicated that intervention group patients had a hazard ratio of 0·19 (P = 0·002) compared to control group patients. We conclude that multi‐layered soft silicone foam dressings are effective in preventing pressure ulcers in critically ill patients when applied in the emergency department prior to ICU transfer.  相似文献   
168.
Targeting Notch signaling in autoimmune and lymphoproliferative disease   总被引:1,自引:0,他引:1  
Patients with autoimmune lymphoproliferative syndrome (ALPS) and systemic lupus erythematosis (SLE) have T-cell dysregulation and produce abnormal, activated T lymphocytes and an atypical peripheral T-cell population, termed double negative T cells (DNTs). T-cell functions, including DNT transition in T-cell development and T-cell activation, are critically dependent on Notch signaling. We hypothesized that inhibiting Notch signaling would be effective in ALPS and SLE by reducing the production of abnormal DNTs and by blocking aberrant T-cell activation. We tested this hypothesis using murine models of ALPS and SLE. Mice were randomized to treatment with the notch pathway inhibitor (gamma-secretase inhibitor), N-S-phenyl-glycine-t-butyl ester (DAPT), or vehicle control. Response to treatment was assessed by measurement of DNTs in blood and lymphoid tissue, by monitoring lymph node and spleen size with ultrasound, by quantifying cytokines by bead-array, by ELISA for total IgG and anti-double-stranded DNA (dsDNA) specific antibodies, and by histopathologic assessment for nephritis. We found a profound and statistically significant decrease in all disease parameters, comparing DAPT-treated mice to controls. Using a novel dosing schema, we avoided the reported toxicities of gamma-secretase inhibitors. Inhibiting the Notch signaling pathway may thus present an effective, novel, and well-tolerated treatment for autoimmune and lymphoproliferative diseases.  相似文献   
169.
Riedel thyroiditis is a rare fibrosing disorder characterized by extension of the fibroinflammatory process beyond the thyroid capsule. Due to the nature of this lesion, fine‐needle aspiration often yields scant material and may be interpreted as non‐diagnostic. In this report, we describe cytologic features that allow the cytopathologist to favor a diagnosis of Riedel thyroiditis, thereby guiding appropriate further work‐up and management. Diagn. Cytopathol. 2015;43:747–750. © 2015 Wiley Periodicals, Inc.  相似文献   
170.
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