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941.
Structural variations (SVs) represent a major source of genetic diversity. However, the functional impact and formation mechanisms of SVs in plant genomes remain largely unexplored. Here, we report a nucleotide-resolution SV map of cucumber (Cucumis sativas) that comprises 26,788 SVs based on deep resequencing of 115 diverse accessions. The largest proportion of cucumber SVs was formed through nonhomologous end-joining rearrangements, and the occurrence of SVs is closely associated with regions of high nucleotide diversity. These SVs affect the coding regions of 1676 genes, some of which are associated with cucumber domestication. Based on the map, we discovered a copy number variation (CNV) involving four genes that defines the Female (F) locus and gives rise to gynoecious cucumber plants, which bear only female flowers and set fruit at almost every node. The CNV arose from a recent 30.2-kb duplication at a meiotically unstable region, likely via microhomology-mediated break-induced replication. The SV set provides a snapshot of structural variations in plants and will serve as an important resource for exploring genes underlying key traits and for facilitating practical breeding in cucumber.  相似文献   
942.
943.

Background

The optimal pacing rate during cardiac resynchronization therapy (CRT) is unknown. Therefore, we investigated the impact of changing basal pacing frequencies on autonomic nerve function, cardiopulmonary exercise capacity and self-perceived quality of life (QoL).

Methods

Twelve CRT patients with non-ischemic heart failure (NYHA class II–III) were enrolled in a randomized, double-blind, crossover trial, in which the basal pacing rate was set at DDD-60 and DDD-80 for 3 months (DDD-R for 2 patients). At baseline, 3 months and 6 months, we assessed sympathetic nerve activity by microneurography (MSNA), peak oxygen consumption (pVO2), N-terminal pro-brain natriuretic peptide (p-NT-proBNP), echocardiography and QoL.

Results

DDD-80 pacing for 3 months increased the mean heart rate from 77.3 to 86.1 (p = 0.001) and reduced sympathetic activity compared to DDD-60 (51±14 bursts/100 cardiac cycles vs. 64±14 bursts/100 cardiac cycles, p<0.05). The mean pVO2 increased non-significantly from 15.6±6 mL/min/kg during DDD-60 to 16.7±6 mL/min/kg during DDD-80, and p-NT-proBNP remained unchanged. The QoL score indicated that DDD-60 was better tolerated.

Conclusion

In CRT patients with non-ischemic heart failure, 3 months of DDD-80 pacing decreased sympathetic outflow (burst incidence only) compared to DDD-60 pacing. However, Qol scores were better during the lower pacing rate. Further and larger scale investigations are indicated.

Trial Registration

ClinicalTrials.gov NCT02258061  相似文献   
944.

Objective

To assess whether systematic follow-up by general practitioners (GPs) of cases of deliberate self-poisoning (DSP) by their patients decreases psychiatric symptoms and suicidal behaviour compared with current practice.

Design

Randomised clinical trial with two parallel groups.

Setting

General practices in Oslo and the eastern part of Akershus County.

Participants

Patients aged 18–75 years admitted to hospital for DSP. We excluded patients diagnosed with psychoses, without a known GP, those not able to complete a questionnaire, and patients admitted to psychiatric in-patient care or other institutions where their GP could not follow them immediately after discharge.

Intervention

The GPs received a written guideline, contacted the patients and scheduled a consultation within one week after discharge, and then provided regular consultations for six months. We randomised the patients to either intervention (n = 78) or treatment as usual (n = 98).

Main Outcome Measures

Primary outcome measure was the Beck Scale for Suicide Ideation (SSI). Secondary outcomes were Beck Depression Inventory (BDI) and Beck Hopelessness Scale (BHS), self-reported further self-harm and treatment for DSP in a general hospital or an emergency medical agency (EMA). We assessed patients on entry to the trial and at three and six months. We collected data from interviews, self-report questionnaires, and hospital and EMA medical records.

Results

There were no significant differences between the groups in SSI, BDI, or BHS mean scores or change from baseline to three or six months. During follow-up, self-reported DSP was 39.5% in the intervention group vs. 15.8% in controls (P = 0.009). Readmissions to general hospitals were similar (13% in both groups (P = 0.963), while DSP episodes treated at EMAs were 17% in the intervention group and 7% in the control group (P = 0.103).

Conclusion

Structured follow-up by GPs after an episode of DSP had no significant effect on suicide ideation, depression or hopelessness. There was no significant difference in repeated episodes of DSP in hospitals or EMAs. However, the total number of incidents of deliberate self-harm reported by the patients was significantly higher in the intervention group.

Trial registration

Trial registration ClinicalTrials.gov Identifier: NCT01342809  相似文献   
945.

Objective

In this study, we examined the concentration of serum immunoglobulin free light chains (FLCs) in systemic lupus erythematosus (SLE) patients and investigated its association with various disease parameters in order to evaluate the role of FLCs as a potential biomarker in SLE. Furthermore, FLCs’ association with Epstein-Barr virus (EBV) antibodies was examined.

Methods

Using a nephelometric assay, κFLC and λFLC concentrations were quantified in sera from 45 SLE patients and 40 healthy controls. SLE patients with renal insufficiency were excluded in order to preclude high concentrations of serum FLCs due to decreased clearance.

Results

Serum FLC concentrations were significantly elevated in SLE patients compared to healthy controls (p<0.0001) also after adjusting for Ig levels (p<0.0001). The concentration of serum FLCs correlated with a global disease activity (SLE disease activity index (SLEDAI)) score of the SLE patients (r = 0.399, p = 0.007). Furthermore, concentrations of FLCs correlated with titers of dsDNA antibodies (r = 0.383, p = 0.009), and FLC levels and SLEDAI scores correlated in the anti-dsDNA-positive SLE patients, but not in anti-dsDNA-negative SLE patients. Total immunoglobulin (IgG and IgA) concentrations correlated with FLC concentrations and elevated FLC levels were additionally shown to associate with the inflammatory marker C-reactive protein and also with complement consumption determined by low C4 in SLE patients. Collectively, results indicated that elevated serum FLCs reflects increased B cell activity in relation to inflammation. SLE patients had an increased seropositivity of EBV-directed antibodies that did not associate with elevated FLC concentrations. An explanation for this could be that serum FLC concentrations reflect the current EBV activity (reactivation) whereas EBV-directed antibodies reflect the extent of previous infection/reactivations.

Conclusion

SLE patients have elevated concentrations of serum FLCs that correlate with global disease activity scores and especially serologic markers for active disease. These findings are suggestive of circulating FLCs having potential as a new supplementary serologic biomarker in SLE.  相似文献   
946.
947.
The article investigates how the concept of victimhood is constructed within debates on transnational prostitution and trafficking, and how representations of victimhood intersect with representations of the person/self, class, ethnicity, gender and nationality. Using research findings based on observation and interviews with women from post-Soviet societies involved in prostitution in Norway, we discuss how the women embrace, resist or rework dominant representations of migrant prostitution and attendant notions of victimhood, as well as how they relate to multiple notions of the person/self, femininity and nation through their handling of the stigma of prostitution  相似文献   
948.
In the filamentous ascomycete Neurospora tetrasperma, a large (approx. 7 Mbp) region of suppressed recombination surrounds the mating-type (mat) locus. While the remainder of the genome is largely homoallelic, this region of recombinational suppression, extending over 1500 genes, is associated with sequence divergence. Here, we used microarrays to examine how the molecular phenotype of gene expression level is linked to this divergent region, and thus to the mating type. Culturing N. tetrasperma on agar media that induce sexual/female or vegetative/male tissue, we found 196 genes significantly differentially expressed between mat A and mat a mating types. Our data show that the genes exhibiting mat-linked expression are enriched in the region genetically linked to mating type, and sequence and expression divergence are positively correlated. Our results indicate that the phenotype of mat A strains is optimized for traits promoting sexual/female development and the phenotype of mat a strains for vegetative/male development. This discovery of differentially expressed genes associated with mating type provides a link between genotypic and phenotypic divergence in this taxon and illustrates a fungal analogue to sexual dimorphism found among animals and plants.  相似文献   
949.
Gall midges are important pests in many crops. In fruit, they are difficult to control due to their life cycle, which takes place partially within the fruit. Here, we provide the first successful laboratory experiment to infect pear gall midge (Contarinia pyrivora) with the insect pathogenic fungus Metarhizium brunneum. We developed a procedure for sampling larvae, maintaining them in the laboratory and subjecting them to the fungus. We demonstrated that dipping larvae in a fungus suspension or adding a fungus suspension to the soil result in significant fungus induced mortality of the pear gall midge. An immune response in treated larvae was recorded proving that there was a real pathogenesis. Finally, we discuss next steps and a strategy for field experiments.  相似文献   
950.
Four halogenated cyclopropane derivatives with a side chain containing a primary (1 and 2) or secondary (3 and 4) alcohol moiety were subject to kinetic resolution catalyzed by lipases. Two of them containing secondary alcohol groups gave excellent results with Candida antarctica lipase B with E-values around 1000. Two enantiopure alcohols and two enantiopure butanoates are described: (1S,1S)-1-(2′,2′-dichloro-3′,3′-dimethylcyclopropyl) ethanol (3), the corresponding (1R,1R)-butanoate (3b) and (1S,1S)-1-(1′-methyl-2′,2′-dibromocyclopropyl) ethanol (4) and the corresponding (1R,1R)-butanoate (4b).  相似文献   
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