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121.
122.
Powdery mildew is the most widespread disease of pea (Pisum sativum L.) and causes severe economic losses worldwide. Recessively inherited er1 powdery mildew resistance, successfully used for decades in pea breeding programs, has recently been shown to originate from the loss of function of the PsMLO1 gene. Five er1 alleles, each corresponding to a different PsMLO1 null mutation, have been characterized to date in pea germplasm. In order to aid er1 selection, we aimed to identify functional markers which target PsMLO1 polymorphisms directly responsible for the resistant phenotype. Highly informative cleaved amplified polymorphic sequence (CAPS), derived cleaved amplified polymorphic sequence (dCAPS), sequence tagged site (STS) and high-resolution melting (HRM) markers were developed which enable the selection of each of the five er1 alleles. Taken together, the results described here provide a powerful tool for breeders, overcoming limitations of previously reported er1-linked markers due to the occurrence of recombination with the resistance locus and/or the lack of polymorphism between parental genotypes. The HRM marker er1-5/HRM54 reported here, targeting a mutagenesis-induced er1 allele recently described by us, does not require manual processing after PCR amplification, and is therefore suitable for large-scale breeding programs based on high-throughput automated screening.  相似文献   
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124.

Background

Dental agenesis is the most common, often heritable, developmental anomaly in humans. Although WNT10A gene mutations are known to cause rare syndromes associated with tooth agenesis, including onycho-odontodermal dysplasia (OODD), Schöpf-Schulz-Passarge syndrome (SSPS), hypohidrotic ectodermal dysplasia (HED), and more than half of the cases of isolated oligodontia recently, the genotype-phenotype correlations and the mode of inheritance of WNT10A mutations remain unclear. The phenotypic expression with WNT10A mutations shows a high degree of variability, suggesting that other genes might function with WNT10A in regulating ectodermal organ development. Moreover, the involvement of mutations in other genes, such as EDA, which is also associated with HED and isolated tooth agenesis, is not clear. Therefore, we hypothesized that EDA mutations interact with WNT10A mutations to play a role in tooth agenesis. Additionally, EDA, EDAR, and EDARADD encode signaling molecules in the Eda/Edar/NF-κB signaling pathways, we also checked EDAR and EDARADD in this study.

Methods

WNT10A, EDA, EDAR and EDARADD were sequenced in 88 patients with isolated oligodontia and 26 patients with syndromic tooth agenesis. The structure of two mutated WNT10A and two mutated EDA proteins was analyzed.

Results

Digenic mutations of both WNT10A and EDA were identified in 2 of 88 (2.27%) isolated oligodontia cases and 4 of 26 (15.38%) syndromic tooth agenesis cases. No mutation in EDAR or EDARADD gene was found.

Conclusions

WNT10A and EDA digenic mutations could result in oligodontia and syndromic tooth agenesis in the Chinese population. Moreover, our results will greatly expand the genotypic spectrum of tooth agenesis.  相似文献   
125.
This study aims to evaluate the effects of Remifemin (isopropanolic extract of Cimicifuga Racemosa) on postmenopausal osteoporosis. 120 female Sprague-Dawley rats were randomly assigned to four groups: sham surgery with vehicle, ovariectomy with vehicle, ovariectomy with estradiol valerate, or ovariectomy with Remifemin. Daily oral administrations of the vehicle, estradiol valerate, or Remifemin began 2 weeks after surgery and lasted to 4, 8, or 12 weeks. Ten rats in each group were sacrificed at each timestep with assessment of bone mineral density, trabecular bone structure, and biomechanical parameters of the femur and lumbar vertebra. Bone turnover markers were evaluated 12 weeks after surgery. Both drugs prevented bone density loss in the distal end of the femur and preserved the trabecular bone structure in both the lumbar vertebra and distal end of the femur following ovariectomy. Both drugs protected bone stiffness at the tested regions and reduced bone reabsorption in ovariectomized rats. The preventive effects of Remifemin against bone-loss can rival those of estradiol valerate if treatment duration is adequately extended. In conclusion, Remifemin may demonstrate equivalent effects to estradiol valerate in terms of preventing postmenopausal osteoporosis.  相似文献   
126.

Background

The world’s first reported patient infected with avian influenza H7N9 was treated at the Fifth People’s Hospital of Shanghai. Shortly thereafter, several other cases emerged in the local area. Here, we describe the detailed epidemiological and clinical data of 6 cases of avian influenza H7N9.

Methods and Findings

We analyzed the epidemiologic and clinical data from clustered patients infected with H7N9 in the Minhang District of Shanghai during a 2-week period. Of the 6 patients, 2 were from a single family. In addition, 3 patients had a history of contact with poultry; however, all 6 patients lived in the proximity of 2 food markets where the H7N9 virus was detected in chickens and pigeons. The main symptoms were fever, cough, and hemoptysis. At onset, a decreased lymphocyte count and elevated creatine kinase, lactate dehydrogenase, procalcitonin, and C-reactive protein levels were observed. As the disease progressed, most patients developed dyspnea and hypoxemia. Imaging studies revealed lung consolidation and multiple ground-glass opacities in the early stage, rapidly extending bilaterally. All patients were treated with oseltamivir tablets beginning on days 3–8 after onset. The main complications were as follows: acute respiratory distress syndrome (ARDS; 83.3%), secondary bacterial infection (66.7%), pleural effusion (50%), left ventricular failure (33.3%), neuropsychiatric symptoms (33.3%), and rhabdomyolysis (16.7%). Of the 6 patients, 4 died of ARDS, with 2 patients recovering from the infection.

Conclusions

An outbreak of H7N9 infection occurred in the Minhang District of Shanghai that easily progressed to acute respiratory distress syndrome. Two cases showed family aggregation, which led us to identify the H7N9 virus and indicated that human transmission may be involved in the spread of this infection.  相似文献   
127.

Background

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, substantially reduces wheat grain yield and quality worldwide. Proteins play important roles in defense against the fungal infection. This study characterized differentially expressed proteins between near-isogenic lines (NILs) contrasting in alleles of Fhb1, a major FHB resistance gene in wheat, to identify proteins underlining FHB resistance of Fhb1.

Methods

The two-dimensional protein profiles were compared between the Fusarium-inoculated spikes of the two NILs collected 72 h after inoculation. The protein profiles of mock- and Fusarium-inoculated Fhb1+NIL were also compared to identify pathogen-responsive proteins.

Results

Eight proteins were either induced or upregulated in inoculated Fhb1+NIL when compared with mock-inoculated Fhb1+NIL; nine proteins were either induced or upregulated in the Fusarium-inoculated Fhb1+NIL when compared with Fusarium-inoculated Fhb1NIL. Proteins that were differentially expressed in the Fhb1+NIL, not in the Fhb1NIL, after Fusarium inoculation included wheat proteins for defending fungal penetration, photosynthesis, energy metabolism, and detoxification.

Conclusions

Coordinated expression of the identified proteins resulted in FHB resistance in Fhb1+NIL. The results provide insight into the pathway of Fhb1-mediated FHB resistance.  相似文献   
128.

Background

Previous meta-analyses that compared the outcome of SILC and CLC have not presented consistent conclusions. This meta-analysis was performed after adding many recent RCTs, to clarify this issue.

Methods

Relevant articles published in English were identified by searching PubMed, Embase, Web of Knowledge, and the Cochrane Controlled Trial Register from January 1997 to February 2013. Reference lists of the retrieved articles were reviewed to identify additional articles. Primary outcomes (postoperative pain scores, cosmetic score, and length of incision) and secondary outcomes (operating time, blood loss, conversion rates, postoperative complications, postoperative hospital stay, time to initial oral intake, and time to resume work) were pooled. Quantitative variables were calculated using the weighted mean difference (WMD), and qualitative variables were pooled using odds ratios (OR).

Results

25 appropriate RCTs were identified from 2128 published articles. 1841 patients were treated, 944 with SILC and 897 with CLC. SILC was superior to CLC in cosmetic score (WMD = 1.155, P<0.001), shorter length of incision (WMD = -3.285, P = 0.029), and postoperative pain within 12 h (VAS in 3-4 h, WMD = -0.704, P = 0.026; VAS in 6-8 h, WMD = -0.613, P = 0.010). CLC was superior to SILC in operating time (OT) (WMD = 13.613, P<0.001) and need of additional instruments (OR = 7.448, P<0.001). Other secondary outcomes were similar.

Conclusions

SILC offered a better cosmetic result and less postoperative pain for patients with uncomplicated cholelithiasis or polypoid lesions of the gallbladder. However, SILC was associated with a longer OT and required additional instruments.  相似文献   
129.
130.
In the biological pretreatment process, white-rot fungi are mostly used to degrade lignin and carbohydrates in lignocellulosic biomass. In this study, water-soluble hemicelluloses were recovered from birch wood (Betula alnoides) decayed by white-rot fungi (Ganoderma lucidum C7016) for different durations up to 16 weeks. Accordingly, the dimethyl sulfoxide (DMSO)-soluble hemicelluloses were isolated from the untreated birch wood as a comparison. Results showed that the fungal-degraded polysaccharides were acidic hemicelluloses having a high content of uronic acids ranging from 20.6 to 22.5 %. Gel permeation chromatography analysis demonstrated that the recovered water-soluble hemicelluloses had a lower average molecular weight (M w, 15,990–27,560 g?mol?1) than that of the DMSO-soluble hemicelluloses (M w , 33,960 g?mol?1). Fourier transform infrared spectroscopy, scanning electron microscopy, one- and two-dimensional nuclear magnetic resonance spectroscopy also revealed significantly changes between those of fungal degraded and DMSO-soluble hemicelluloses. It was proposed that the hemicelluloses with low molecular weights were easily removed from wood by fungal degradation. This research revealed the changes of hemicelluloses in fungal degradation in the natural environment, which may enable the exploration of novel methods in bioconversion of lignocellulosic biomass for the production of biofuels and biopolymers, in addition to the development of new and better ways to protect wood from biodegradation by microorganisms.  相似文献   
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