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91.
The barley stem rust resistance gene Reaction to Puccinia graminis 1 (Rpg1), encoding a receptor-like kinase, confers durable resistance to the stem rust pathogen Puccinia graminis f. sp. tritici. The fungal urediniospores form adhesion structures with the leaf epidermal cells within 1 h of inoculation, followed by hyphae and haustorium formation. The RPG1 protein is constitutively expressed and not phosphorylated. On inoculation with avirulent urediniospores, it is phosphorylated in vivo within 5 min and subsequently degraded. Application of arginine-glycine-aspartic acid peptide loops prevented the formation of adhesion structures for spore attachment, the phosphorylation of RPG1, and germination of the viable spores. Arginine-glycine-aspartic acid affinity chromatography of proteins from the ungerminated avirulent rust spores led to the purification and identification of a protein with fibronectin type III and breast cancer type 1 susceptibility protein domains and a vacuolar protein sorting-associated protein 9 with a coupling of ubiquitin to endoplasmic reticulum degradation domain. Both proteins are required to induce in vivo phosphorylation and degradation of RPG1. Combined application of both proteins caused hypersensitive reaction on the stem rust-resistant cultivar Morex but not on the susceptible cultivar Steptoe. Expression studies indicated that mRNA of both genes are present in ungerminated urediniospores and are constitutively transcribed in sporelings, infected leaves, and haustoria in the investigated avirulent races. Evidence is presented that RPG1, in yeast, interacts with the two protein effectors from the urediniospores that activate cooperatively the stem rust resistance protein RPG1 long before haustoria formation.  相似文献   
92.
BACKGROUND: Diabetic retinopathy and proteinuria, manifestations of microvascular abnormalities, occur early in the course of diabetes mellitus; in contrast, macrovascular cardiovascular complications usually occur later. Retinal vessel characteristics may be informative about risk of cardiovascular disease in persons with diabetes. We evaluated this in a longitudinal cohort study of persons with type 1 diabetes. METHODS: The population consisted of persons with type 1 diabetes who were receiving care in 11 counties in Wisconsin. Subjects (n = 996) were examined at baseline (1980-1982), and 4, 10, 14, and 20 years later. Evaluations included medical history and measurements of height, weight, blood pressure, and glycosylated hemoglobin. Fundus photographs were graded for diabetic retinopathy at baseline, and the same photographs were graded later for the diameters of retinal blood vessels. At each examination, a history of cardiovascular disease events since the last examination (and prior to baseline) was obtained. Mortality was monitored yearly. RESULTS: The 20-year age-adjusted cumulative incidences were 18.1% for angina, 14.8% for myocardial infarction, and 5.9% for stroke. Severity of diabetic retinopathy was associated with angina and stroke. Arteriovenous ratio was associated with myocardial infarction. Of 273 deaths, 176 involved heart disease. The severity of retinopathy and arteriovenous ratio was associated with heart disease mortality. Nephropathy was more informative about the cardiovascular end points than were the blood vessel characteristics. CONCLUSIONS: Incidences of cardiovascular disease, including mortality, were common in people with type 1 diabetes during a 20-year interval. Retinal vascular characteristics were associated with these end points, but this association was confounded by nephropathy.  相似文献   
93.
Low reorganization free energies are necessary for fast electron transfer (ET) reactions. Hence, rational design of redox proteins with lower reorganization free energies has been a long-standing challenge, promising to yield a deeper understanding of the underlying principles of ET reactivity and to enable potential applications in different energy conversion systems. Herein we report studies of the intramolecular ET from pulse radiolytically produced disulfide radicals to Cu(II) in rationally designed azurin mutants. In these mutants, the copper coordination sphere has been fine-tuned to span a wide range of reduction potentials while leaving the metal binding site effectively undisrupted. We find that the reorganization free energies of ET within the mutants are indeed lower than that of WT azurin, increasing the intramolecular ET rate constants almost 10-fold: changes that are correlated with increased flexibility of their copper sites. Moreover, the lower reorganization free energy results in the ET rate constants reaching a maximum value at higher driving forces, as predicted by the Marcus theory.  相似文献   
94.
Epidemiologic data suggest that early nutritional exposures may inflict persistent changes in the developing mammalian "super-organism" (i.e., the host and its residing microbiota). Such persistent modifications could predispose young adults to inflammatory bowel diseases (IBD). We recently observed that the dietary supplementation of four micronutrients to dams augmented colitis susceptibility in murine offspring in association with mucosal microbiota composition changes. In this study the effects of the four micronutrients on the microbiota of dams and female mice was examined. Additionally, age dependent microbiota composition shifts during pediatric development were delineated from the previous offspring data sets. Maternal and adult female microbiota did not separate secondary to the nutritional intervention. Significant microbiota composition changes occurred from postnatal day 30 (P30) to P90 at the level of 1 phylum and 15 genera. Most of these changes were absent or opposite in the maternally supplemented offspring. Nutritionally induced alterations in mucosal microbiota maturation may be contributors to colitis susceptibility in mammals.  相似文献   
95.
Summary The effect of 15-Deoxyspergualin, a novel drug which has been described to have anti-tumour activity, on allogeneic graft survival (Dark Agouti Lewis rats) after pancreatic islet transplantation was tested. A marked prolongation of graft survival could be shown using doses of 1.0, 2.5 and 5.0mg Deoxyspergualin/kg on day 0 until day +9 post transplantation. A maximum of 55.6 days (average) survival time was observed using 2.5mg/kg Deoxyspergualin compared to 5.2±0.6 days without immunosuppression. Using the chemiluminescence reaction of recipient monocytes after islet transplantation, a marked suppression of the monocyte system exceeding the treatment period could be observed. Since, in contrast to cyclosporin, B-cell toxicity could not be shown, the new drug seems to be a hopeful step towards successful allogeneic islet transplantation for treatment of diabetes.  相似文献   
96.
There is limited research on plaque characteristics of ST elevation myocardial infarction (STEMI) patients according to the gender and age. 280 Consecutive STEMI patients who underwent VH-IVUS imaging on culprit before percutaneous coronary intervention (PCI) were enrolled in this study. Women were significantly older than men (69.8 ± 10 vs. 55.9 ± 11.3, p < 0.001). After propensity matching, men had higher plaque burden (79.7 ± 7.8 vs. 73.7 ± 13.0 %, p = 0.010), more fibro-fatty tissue (12.8 ± 9.9 vs. 9.5 ± 6.8 %, p = 0.04) and less dense calcium than women (8.4 ± 5.8 vs. 12.3 ± 8.7 %, p = 0.007). Subgroups dividing by 50, 65, 75 years old, plaque burden was higher in elderly men aged 66–75 years compared to the young men aged less than 50 (75.5 ± 9.2 vs. 68.4 ± 10.1 %, p = 0.012). And middle aged men ranged 51–65 years showed significantly more plaque burden at minimal lumen area site than matched aged women (77.5 ± 8.0 vs. 69.0 ± 17.6 %, p = 0.012). Elderly women aged 66–75 years showed significantly more necrotic core (28.6 ± 7.3 %) and dense calcium (14.9 ± 7.5 %) compared to all the younger or matched subgroups of men. These differences in plaque composition are blunted in the very elderly of men and women aged over 75 years. The findings may explain the gender differences in clinical prognosis in STEMI patients.  相似文献   
97.
BackgroundRadial artery access has been shown to reduce mortality and bleeding events, especially in patients with acute coronary syndromes. Despite this, interventional cardiologists experienced in femoral artery access still prefer that route for percutaneous coronary intervention. Little is known regarding the merits of each vascular access in patients stratified by their risk of bleeding.MethodsPatients from the Global Leaders trial were dichotomized into low or high risk of bleeding by the median of the PRECISE-DAPT score. Clinical outcomes were compared at 30 days.ResultsIn the overall population, there were no statistical differences between radial and femoral access in the rate of the primary end point, a composite of all-cause mortality, or new Q-wave myocardial infarction (MI) (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.42-1.15). Radial access was associated with a significantly lower rate of the secondary safety end point, Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding (HR 0.55, 95% CI 0.36-0.84). Compared by bleeding risk strata, in the high bleeding score population, the primary (HR 0.47, 95% CI 0.26-0.85; P = 0.012; Pinteraction = 0.019) and secondary safety (HR 0.57, 95% CI 0.35-0.95; P = 0.030; Pinteraction = 0.631) end points favoured radial access. In the low bleeding score population, however, the differences in the primary and secondary safety end points between radial and femoral artery access were no longer statistically significant.ConclusionsOur findings suggest that the outcomes of mortality or new Q-wave MI and BARC 3 or 5 bleeding favour radial access in patients with a high, but not those with a low, risk of bleeding. Because this was not a primary analysis, it should be considered hypothesis generating.  相似文献   
98.
99.

Objectives

The aim of the study was to evaluate the long‐term response to antiretroviral treatment (ART) based on atazanavir/ritonavir (ATZ/r)‐, darunavir/ritonavir (DRV/r)‐, and lopinavir/ritonavir (LPV/r)‐containing regimens.

Methods

Data were analysed for 5678 EuroSIDA‐enrolled patients starting a DRV/r‐, ATZ/r‐ or LPV/r‐containing regimen between 1 January 2000 and 30 June 2013. Separate analyses were performed for the following subgroups of patients: (1) ART‐naïve subjects (8%) at ritonavir‐boosted protease inhibitor (PI/r) initiation; (2) ART‐experienced individuals (44%) initiating the new PI/r with a viral load (VL) ≤500 HIV‐1 RNA copies/mL; and (3) ART‐experienced patients (48%) initiating the new PI/r with a VL >500 copies/mL. Virological failure (VF) was defined as two consecutive VL measurements >200 copies/mL ≥24 weeks after PI/r initiation. Kaplan–Meier and multivariable Cox models were used to compare risks of failure by PI/r‐based regimen. The main analysis was performed with intention‐to‐treat (ITT) ignoring treatment switches.

Results

The time to VF favoured DRV/r over ATZ/r, and both were superior to LPV/r (log‐rank test; P < 0.02) in all analyses. Nevertheless, the risk of VF in ART‐naïve patients was similar regardless of the PI/r initiated after controlling for potential confounders. The risk of VF in both treatment‐experienced groups was lower for DRV/r than for ATZ/r, which, in turn, was lower than for LPV/r‐based ART.

Conclusions

Although confounding by indication and calendar year cannot be completely ruled out, in ART‐experienced subjects the long‐term effectiveness of DRV/r‐containing regimens appears to be greater than that of ATZ/r and LPV/r.
  相似文献   
100.
Graft-versus-host disease (GvHD) caused by alloreactive T cells within the graft is a major drawback of allogeneic BMT, but depletion of T cells leads to higher rates of relapse, opportunistic infections and graft failure. Therefore, selective removal of GvHD-inducing alloreactive T cells might be beneficial. We describe here the separation of alloresponsive T cells, based on carboxyfluorescein succimidyl ester labeling, in vitro allostimulation and FACS-sorting. In vivo effects of the separated cell populations were investigated in the context of allogeneic BMT in murine models: in vitro resting T cells were shown to survive in the allogeneic host and retain immunoreactivity against 'third-party' antigens. As demonstrated in two different transplantation models, elimination of proliferating cells significantly reduces GvHD but offers no advantages to using T-cell-depleted bone marrow alone concerning engraftment and tumor control. Transplanting T cells that proliferate in response to tumor antigens in vitro may narrow down the spectrum of antigens recognized by T cells and therefore reduce GvHD while maintaining graft-facilitating function and tumor control. Therefore, selecting tumor-reactive T cells on the basis of their proliferative response in vitro may be beneficial for the recipient, less time consuming than T-cell cloning and still reduce the extent of GvHD.  相似文献   
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