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1.
Use of E. coli strains with phenotypes Rec+ and Rec- asrecipients in intergenera crosses confirmed the supposition put forward by the authors formerly that new chromosomal markers in transconjugantes originated due to Psuedomonas aeruginosa. These chromosomal markers were transferred together with plasmid R conditioning the conjugation, and maintained without being built-into E. coli chromosome. Between the arg+ marker and the plasmid R18 there existed labile physical connection demonstrable only under definite conditions of recombinant selection.  相似文献   
2.
The experimental data of previous papers are considered as a basis for the hypothesis about intraneuronal system controlled by cyclic nucleotides and changing the membrane permeability upon creating the generatory potential. This system is suggested to be an extremal molecular regulator in which the price of action per single operation approximates the physical limit. The electro-mechanical intraneuronal system is capable of solving multidimensional physical problems by means of molecular "digital" hypersound holo-gram coded by DNA molecular text which is an image of functions of target search.  相似文献   
3.
Beyond its role in cellular homeostasis, autophagy plays anti‐ and promicrobial roles in host–microbe interactions, both in animals and plants. One prominent role of antimicrobial autophagy is to degrade intracellular pathogens or microbial molecules, in a process termed xenophagy. Consequently, microbes evolved mechanisms to hijack or modulate autophagy to escape elimination. Although well‐described in animals, the extent to which xenophagy contributes to plant–bacteria interactions remains unknown. Here, we provide evidence that Xanthomonas campestris pv. vesicatoria (Xcv) suppresses host autophagy by utilizing type‐III effector XopL. XopL interacts with and degrades the autophagy component SH3P2 via its E3 ligase activity to promote infection. Intriguingly, XopL is targeted for degradation by defense‐related selective autophagy mediated by NBR1/Joka2, revealing a complex antagonistic interplay between XopL and the host autophagy machinery. Our results implicate plant antimicrobial autophagy in the depletion of a bacterial virulence factor and unravel an unprecedented pathogen strategy to counteract defense‐related autophagy in plant–bacteria interactions.  相似文献   
4.
Vesicle trafficking plays an important role in cell division, establishment of cell polarity, and translation of environmental cues to developmental responses. However, the molecular mechanisms regulating vesicle trafficking remain poorly understood. Here, we report that the evolutionarily conserved caspase-related protease separase (EXTRA SPINDLE POLES [ESP]) is required for the establishment of cell polarity and cytokinesis in Arabidopsis thaliana. At the cellular level, separase colocalizes with microtubules and RabA2a (for RAS GENES FROM RAT BRAINA2a) GTPase-positive structures. Separase facilitates polar targeting of the auxin efflux carrier PIN-FORMED2 (PIN2) to the rootward side of the root cortex cells. Plants with the radially swollen4 (rsw4) allele with compromised separase activity, in addition to mitotic failure, display isotropic cell growth, perturbation of auxin gradient formation, slower gravitropic response in roots, and cytokinetic failure. Measurements of the dynamics of vesicle markers on the cell plate revealed an overall reduction of the delivery rates of KNOLLE and RabA2a GTPase in separase-deficient roots. Furthermore, dissociation of the clathrin light chain, a protein that plays major role in the formation of coated vesicles, was slower in rsw4 than in the control. Our results demonstrate that separase is a key regulator of vesicle trafficking, which is indispensable for cytokinesis and the establishment of cell polarity.  相似文献   
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6.

Background

Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.

Methods

Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.

Results

Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.

Conclusions

Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.

Trial Registration

ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/  相似文献   
7.
Russian Journal of Genetics - The results of the study of chromosomal aberrations and micronuclei in blood lymphocytes, as well as micronuclei in buccal epithelium cells of 50 untreated men with...  相似文献   
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Effects of medium viscosity on kinetic parameters of poly(U) hydrolysis catalyzed by RNase from Bac. intermedius 7P (binase) were studied in solutions of sucrose (4-50 wt. %) and glycerol (35-62 wt. %) in Tris--sodium acetate buffer (pH 7.5) at 25 degreesC. The rate constant of reaction kcat was practically unchanged over a wide range of viscosities (1-15 cP for sucrose and 2.5-3 cP for glycerol). In glycerol solutions, kcat slightly increased with viscosity increase from 4 to 10 cP. Addition of NaCl to the buffer medium resulted in an inhibitory effect of Na+ on kcat, prevented by 50% sucrose or 60% glycerol. It is concluded that binase-catalyzed poly(U) cleavage occurs through a "tense"-substrate mechanism, similarly to reactions catalyzed by alpha-chymotrypsin, trypsin, and laccase.  相似文献   
10.
Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr   相似文献   
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