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221.
The factors that explain the competition between intramolecular NO linkage photoisomerization and NO photorelease in five ruthenium nitrosyl complexes were investigated. By applying DFT-based methods, it was possible to characterize the ground states and lowest triplet potential energy surfaces of these species, and to establish that both photoisomerization and photorelease processes can occur in the lowest triplet state of each species. This work highlights the crucial role of the sideways-bonded isomer, a metastable state also known as the MS2 isomer, in the photochemical loss of NO, while the results obtained also indicate that the population of the triplet state of this isomer is compulsory for both processes and show how photoisomerization and photorelease interfere.
Graphical Abstract Illustration of the crucial role of the 3MS2 state in the photoreactivities of ruthenium nitrosyl complexes
  相似文献   
222.

Objectives

To assess the impact of a standardized pre-operative telephone checklist on the rate of late cancellations of ambulatory surgery (AMBUPROG trial).

Design

Multicenter, two-arm, parallel-group, open-label randomized controlled trial.

Setting

11 university hospital ambulatory surgery units in Paris, France.

Participants

Patients scheduled for ambulatory surgery and able to be reached by telephone.

Intervention

A 7-item checklist designed to prevent late cancellation, available in five languages and two versions (for children and adults), was administered between 7 and 3 days before the planned date of surgery, by an automated phone system or a research assistant. The control group received standard management alone.

Main Outcome Measures

Rate of cancellation on the day of surgery or the day before.

Results

The study population comprised 3900 patients enrolled between November 2012 and September 2013: 1950 patients were randomized to the checklist arm and 1950 patients to the control arm. The checklist was administered to 68.8% of patients in the intervention arm, 1002 by the automated phone system and 340 by a research assistant. The rate of late cancellation did not differ significantly between the checklist and control arms (109 (5.6%) vs. 113 (5.8%), adjusted odds ratio [95% confidence interval] = 0.91 [0.65–1.29], (p = 0.57)). Checklist administration revealed that 355 patients (28.0%) had not undergone tests ordered by the surgeon or anesthetist, and that 254 patients (20.0%) still had questions concerning the fasting state.

Conclusions

A standardized pre-operative telephone checklist did not avoid late cancellations of ambulatory surgery but enabled us to identify several frequent causes.

Trial Registration

ClinicalTrials.gov NCT01732159  相似文献   
223.

Objective

Both Premenstrual Syndrome (PMS) and Premenstrual Dysphoric Disorder (PMDD) might increase the risk of suicidal behavior. The aim of this study was to assess the relationship between personality dimensions specifically involved in suicidal vulnerability and PMS/PMDD.

Method

We collected data from 232 women consecutively hospitalized after a suicide attempt. We examined the relationship between impulsivity, aggressiveness/hostility, hopelessness, trait anger, affect intensity, emotional lability, and PMS/PMDD. Notably, we created an algorithm from the shortened Premenstrual Assessment form in order to assess PMDD status.

Results

The proportions of PMS and PMDD among female suicide attempters were 50% and 23% respectively. Women with PMS or PMDD were more likely to endorse most of these personality traits to than those without even after controlling for potential confounders. We found an impulsive-aggressive pattern of personality in women with PMS or PMDD, independently from the time of the menstrual cycle. Interestingly, trait anger remained associated with both PMS and PMDD independently of every other personality traits. The higher the anger level, the higher the risk was to suffer from both PMS and PMDD.

Conclusions

This study demonstrates a strong, independent association between PMS/PMDD and trait anger among a representative sample of female suicide attempters. It is of major interest for clinicians in view of addressing a substantial public health problem among women of reproductive age.  相似文献   
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This paper reports a quantitative genetics and genomic analysis of undesirable coat color patterns in goats. Two undesirable coat colors have routinely been recorded for the past 15 years in French Saanen goats. One fifth of Saanen females have been phenotyped “pink” (8.0%) or “pink neck” (11.5%) and consequently have not been included in the breeding program as elite animals. Heritability of the binary “pink” and “pink neck” phenotype, estimated from 103,443 females was 0.26 for “pink” and 0.21 for “pink neck”. Genome wide association studies (using haplotypes or single SNPs) were implemented using a daughter design of 810 Saanen goats sired by 9 Artificial Insemination bucks genotyped with the goatSNP50 chip. A highly significant signal (-log10pvalue = 10.2) was associated with the “pink neck” phenotype on chromosome 11, suggesting the presence of a major gene. Highly significant signals for the “pink” phenotype were found on chromosomes 5 and 13 (-log10p values of 7.2 and, 7.7 respectively). The most significant SNP on chromosome 13 was in the ASIP gene region, well known for its association with coat color phenotypes. Nine significant signals were also found for both traits. The highest signal for each trait was detected by both single SNP and haplotype approaches, whereas the smaller signals were not consistently detected by the two methods. Altogether these results demonstrated a strong genetic control of the “pink” and “pink neck” phenotypes in French Saanen goats suggesting that SNP information could be used to identify and remove undesired colored animals from the breeding program.  相似文献   
226.
ABSTRACT

The hydatidiform mole (HM) is a placental pathology of androgenetic origin. Placental villi have an abnormal hyperproliferation event and hydropic degeneration. Three situations can be envisaged at its origin: 1. The destruction/expulsion of the female pronucleus at the time of fertilization by 1 or 2 spermatozoa with the former being followed by an endoreplication of the male pronucleus leading to a complete hydatidiform mole (CHM) 2. A triploid zygote (fertilization by 2 spermatozoa) leading to a partial hydatidiform mole (PHM) but can also lead to haploid and diploid clones. The diploid clone may produce a normal fetus while the haploid clone after endoreplication generates a CHM 3. A nutritional defect during the differentiation of the oocytes or the deterioration of the limited oxygen pressure during the first trimester of gestation may lead to the formation of a HM.

In countries with poor medical health care system, moles (mainly the CHM) can become invasive or, in rare cases, lead to gestational choriocarcinomas.  相似文献   
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229.
The biomass productivity of the energy willow Salix viminalis as a short-rotation woody crop depends on organ structure and functions that are under the control of genome size. Colchicine treatment of axillary buds resulted in a set of autotetraploid S. viminalis var. Energo genotypes (polyploid Energo [PP-E]; 2n = 4x = 76) with variation in the green pixel-based shoot surface area. In cases where increased shoot biomass was observed, it was primarily derived from larger leaf size and wider stem diameter. Autotetraploidy slowed primary growth and increased shoot diameter (a parameter of secondary growth). The duplicated genome size enlarged bark and wood layers in twigs sampled in the field. The PP-E plants developed wider leaves with thicker midrib and enlarged palisade parenchyma cells. Autotetraploid leaves contained significantly increased amounts of active gibberellins, cytokinins, salicylic acid, and jasmonate compared with diploid individuals. Greater net photosynthetic CO2 uptake was detected in leaves of PP-E plants with increased chlorophyll and carotenoid contents. Improved photosynthetic functions in tetraploids were also shown by more efficient electron transport rates of photosystems I and II. Autotetraploidization increased the biomass of the root system of PP-E plants relative to diploids. Sections of tetraploid roots showed thickening with enlarged cortex cells. Elevated amounts of indole acetic acid, active cytokinins, active gibberellin, and salicylic acid were detected in the root tips of these plants. The presented variation in traits of tetraploid willow genotypes provides a basis to use autopolyploidization as a chromosome engineering technique to alter the organ development of energy plants in order to improve biomass productivity.Energy security and climate change as global problems urge increased efforts to use plants as renewable energy sources both for power generation and transportation fuel production. Selected wood species, such as willows (Salix spp.), can be cultivated as short-rotation coppice for the rapid accumulation of biomass and reduction of CO2 emission. Coppicing reinvigorates shoot growth, resulting in a special woody plant life cycle that differs from natural tree development, which takes decades. In this cultivation system, small stem cuttings are planted at high densities (15,000–25,000 ha−1). In the soil, these dormant wood cuttings first produce roots and shoots that emerge from reactivated buds. During the first year, the growing shoots mature to woody stems. In the winter, these stems are cut back, and in the following spring, the cut stumps develop multiple shoots. The short-rotation coppice plantations are characterized by a very short, 2- to 3-year rotation, and the most productive varieties can produce up to 15 tons of oven-dried wood per hectare per year (Cunniff and Cerasuolo, 2011). The high-density willow plantations can also be efficiently used for heavy metal or organic phytoremediation, as reviewed by Marmiroli et al. (2011).The biomass productivity of shrub willows is largely dependent on coppicing capability, early vigorous growth, shoot growth rate and final stem height, root system size, photosynthetic efficiency, formation and composition of woody stems, water and nutrient use, as well as abiotic and biotic stress tolerance. Genetic improvement of all these traits can be based on broad natural genetic resources represented by more than 400 species in the genus Salix. More than 200 species have hybrid origins, and ploidy levels vary from diploid up to dodecaploid (Suda and Argus, 1968; Newsholme, 1992). In addition to molecular marker-assisted clone selection, intraspecific and interspecific crosses have been shown to further extend genetic variability in breeding programs for biomass yield (Karp et al., 2011).During natural diversification and artificial crossings of Salix spp., the willow genomes frequently undergo polyploidization, resulting in triploid or tetraploid allopolyploids. In triploid hybrids, both heterosis and ploidy can contribute to the improved biomass yield (Serapiglia et al., 2014). While the alloploid triploids have attracted considerable attention in willow improvement, the potentials of autotetraploid willow genotypes have not been exploited so far. As shown for other short-rotation wood species (poplar [Populus spp.], black locust [Robinia pseudoacacia], Paulownia spp., and birch [Betula spp.]), doubling the chromosome set by colchicine treatment can cause significant changes in organ morphology or growth parameters (Tang et al., 2010; Cai and Kang, 2011; Harbard et al., 2012; Mu et al., 2012; Wang et al., 2013a, 2013b). In several polyploidization protocols, the in vitro cultured tissues are exposed to different doses of colchicine or other inhibitors of mitotic microtubule function, and plantlets are differentiated from polyploid somatic cells (Tang et al., 2010; Cai and Kang, 2011). Alternatively, seeds or apical meristems of germinating seedlings can be treated with a colchicine solution (Harbard et al., 2012). Allotetraploids of poplar were produced by zygotic chromosome doubling that was induced by colchicine and high-temperature treatment (Wang et al., 2013a).Since tetraploid willow plants with 2n = 4x = 76 chromosomes are expected to represent novel genetic variability, especially for organ development and physiological parameters, a polyploidization project was initiated that was based on a highly productive diploid energy willow (S. viminalis var. Energo). Colchicine treatment of reactivated axillary buds of the in vitro-grown energy willow plantlets resulted in autotetraploid shoots and, subsequently, plants. For comparison of diploid and tetraploid variants of willow plants, digital imaging of green organs and roots was used for phenotyping. Among the tetraploid lines, genotypes were identified with improved biomass production, better photosynthetic parameters, and altered organ structure and hormone composition. The new tetraploid willow variants produced can serve as a unique experimental material to uncover key factors in biomass production in this short-rotation energy plant. In the future, these plants can also serve as crossing partners of diploid lines for the production of novel triploid energy willow genotypes.  相似文献   
230.
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