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81.
Identification of the self-incompatibility locus F-box protein-containing complex in Petunia inflata
The polymorphic S-locus regulating self-incompatibility (SI) in Petunia contains the S-RNase gene and a number of S-locus F-box (SLF) genes. While penetrating the style through the stigma, a pollen tube takes up all S-RNases, but only self S-RNase inhibits pollen tube growth. Recent evidence suggests that SLFs produced by pollen collectively interact with and detoxify non-self S-RNases, but none can interact with self S-RNase. An SLF may be the F-box protein component of an SCF complex (containing Cullin1, Skp1 and Rbx1), which mediates ubiquitination of protein substrates for degradation by the 26S proteasome. However, the precise nature of the complex is unknown. We used pollen extracts of a transgenic plant over-expressing GFP-fused S2-SLF1 (SLF1 of S 2-haplotype) for co-immunoprecipitation (Co-IP) followed by mass spectrometry (MS). We identified PiCUL1-P (a pollen-specific Cullin1), PiSSK1 (a pollen-specific Skp1-like protein) and PiRBX1 (an Rbx1). To validate the results, we raised transgenic plants over-expressing PiSSK1:FLAG:GFP and used pollen extracts for Co-IP–MS. The results confirmed the presence of PiCUL1-P and PiRBX1 in the complex and identified two different SLFs as the F-box protein component. Thus, all but Rbx1 of the complex may have evolved in SI, and all SLFs may be the F-box component of similar complexes. 相似文献
82.
83.
Chih-Wei Wang Yi-Jui Liu Yi-Hsiung Lee Dueng-Yuan Hueng Hueng-Chuen Fan Fu-Chi Yang Chun-Jen Hsueh Hung-Wen Kao Chun-Jung Juan Hsian-He Hsu 《PloS one》2014,9(7)
Purpose
To investigate the performance of hematoma shape, hematoma size, Glasgow coma scale (GCS) score, and intracerebral hematoma (ICH) score in predicting the 30-day mortality for ICH patients. To examine the influence of the estimation error of hematoma size on the prediction of 30-day mortality.Materials and Methods
This retrospective study, approved by a local institutional review board with written informed consent waived, recruited 106 patients diagnosed as ICH by non-enhanced computed tomography study. The hemorrhagic shape, hematoma size measured by computer-assisted volumetric analysis (CAVA) and estimated by ABC/2 formula, ICH score and GCS score was examined. The predicting performance of 30-day mortality of the aforementioned variables was evaluated. Statistical analysis was performed using Kolmogorov-Smirnov tests, paired t test, nonparametric test, linear regression analysis, and binary logistic regression. The receiver operating characteristics curves were plotted and areas under curve (AUC) were calculated for 30-day mortality. A P value less than 0.05 was considered as statistically significant.Results
The overall 30-day mortality rate was 15.1% of ICH patients. The hematoma shape, hematoma size, ICH score, and GCS score all significantly predict the 30-day mortality for ICH patients, with an AUC of 0.692 (P = 0.0018), 0.715 (P = 0.0008) (by ABC/2) to 0.738 (P = 0.0002) (by CAVA), 0.877 (P<0.0001) (by ABC/2) to 0.882 (P<0.0001) (by CAVA), and 0.912 (P<0.0001), respectively.Conclusion
Our study shows that hematoma shape, hematoma size, ICH scores and GCS score all significantly predict the 30-day mortality in an increasing order of AUC. The effect of overestimation of hematoma size by ABC/2 formula in predicting the 30-day mortality could be remedied by using ICH score. 相似文献84.
Background
Few studies have examined the association of rheumatoid arthritis (RA) with nontuberculosis mycobacterium (NTM) disease and pulmonary tuberculosis (PTB).Methods
We identified 29 131 patients with RA from the catastrophic illness registry who were diagnosed from 1998–2008; 116 524 patients without RA from inpatient data files were randomly frequency matched according to sex, age, and index year and used as a comparison group. Both groups were followed-up until the end of 2010 to measure the incidence of NTM disease and active PTB. We analyzed the risk of NTM disease and active PTB using the Cox proportional hazards regression models, controlling for sex, age, and Charlson comorbidity index (CCI).Results
The incidence of NTM disease was 4.22 times greater in the RA group than in the non-RA group (1.91 vs 0.45 per 10,000 person-years). The incidence of PTB was 2.99 times greater in the RA group than in the non-RA group (25.3 vs 8.46 per 10,000 person-years). After adjusting for age, sex, and CCI, the adjusted hazard ratios (HRs) of NTM disease and active PTB for the RA group were 4.17 (95% CI = 2.61–6.65) and 2.87 (95% CI = 2.55–3.23), respectively, compared with the non-RA group. In the first 2 years of follow-up, the RA group yielded corresponding adjusted HRs of 4.98 and 3.39 compared with the non-RA group. The follow-up time-specific RA group to the non-RA group HR of both the NTM disease and active PTB varied.Conclusion
This study can serve as a reference for clinical physicians to increase awareness regarding the detection of NTM disease and active PTB in RA patients among the any stage of the clinical course even without CCI. 相似文献85.
Li-Ting Kao Shih-Ping Liu Herng-Ching Lin Hsin-Chien Lee Ming-Chieh Tsai Shiu-Dong Chung 《PloS one》2014,9(12)
Background
Some studies suggested that psychological stress may be associated with the severity and duration of infectious diseases. In this population-based study, we investigated associations between depressive disorder (DD) and pneumonia outcomes in Taiwan with a large-scale database from the National Health Insurance.Methods
Our study defined 112,198 patients who were hospitalized with a principal diagnosis of pneumonia. We defined their admission date for treatment of pneumonia as the index date. Subsequently, we selected 2,394 patients with DD within 3 years prior to their index date and 11,970 matched patients without DD. We carried out separate conditional logistic regressions to explore the association of clinical pneumonia treatment outcome (ICU admission, use of mechanical ventilation, acute respiratory failure and in-hospital death) with previously diagnosed DD.Results
Patients with DD had a significantly higher probability of an intensive care unit admission (18.1% vs. 12.9%; p<0.001), need for mechanical ventilation (21.9% vs. 18.1%; p<0.001) and in-hospital death (10.4% vs. 9.0%; p = 0.025) than patients without DD. The study showed that pneumonia patients with DD were respectively 1.41- (95% CI: 1.25∼1.59, p<0.001), 1.28- (95% CI: 1.14∼1.43, p<0.001), and 1.17- times (95% CI: 1.01∼1.36, p = 0.039) greater odds of being admitted to the ICU, need for mechanical ventilation, and in-hospital death than patients without DD after adjusting for monthly income, urbanization level, geographic region and Charlson Comorbidity Index score.Conclusions
In conclusion, we found that pneumonia patients with DD were associated with poor treatment outcomes compared to patients without DD. 相似文献86.
Chih-Hao Tang Yun-Ren Lai Yi-Chung Chen Chen-Hsiu Li Yu-Fen Lu Hung-Yen Chen Huang-Wei Lien Chung-Hsiang Yang Chang-Jen Huang Chen-Yi Wang Cheng-Fu Kao Sheng-Ping L. Hwang 《Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms》2014,1839(6):425-437
AGR2 is a member of the protein disulfide isomerase (PDI) family, which is implicated in cancer cell growth and metastasis, asthma, and inflammatory bowel disease. Despite the contributions of this protein to several biological processes, the regulatory mechanisms controlling expression of the AGR2 gene in different organs remain unclear. Zebrafish anterior gradient 2 (agr2) is expressed in several organs, including the otic vesicles that contain mucus-secreting cells. To elucidate the regulatory mechanisms controlling agr2 expression in otic vesicles, we generated a Tg(− 6.0 k agr2:EGFP) transgenic fish line that expressed EGFP in a pattern recapitulating that of agr2. Double immunofluorescence studies were used to demonstrate that Agr2 and GFP colocalize in the semicircular canals and supporting cells of all sensory patches in the otic vesicles of Tg(− 6.0 k agr2:EGFP) embryos. Transient/stable transgenic analyses coupled with 5′-end deletion revealed that a 100 bp sequence within the − 2.6 to − 2.5 kbp region upstream of agr2 directs EGFP expression specifically in the otic vesicles. Two HMG-binding motifs were detected in this region. Mutation of these motifs prevented EGFP expression. Furthermore, EGFP expression in the otic vesicles was prevented by knockdown of the sox10 gene. This corresponded with decreased agr2 expression in the otic vesicles of sox10 morphants during different developmental stages. Electrophoretic mobility shift assays were used to show that Sox10 binds to HMG-binding motifs located within the − 2.6 to − 2.5 kbp region upstream of agr2. These results demonstrate that agr2 expression in the otic vesicles of zebrafish embryos is regulated by Sox10. 相似文献
87.
Kuo-Hsiang Chuang Yuan-Chin Hsieh I-Shiuan Chiang Chih-Hung Chuang Chien-Han Kao Ta-Chun Cheng Yeng-Tseng Wang Wen-Wei Lin Bing-Mae Chen Steve R. Roffler Ming-Yii Huang Tian-Lu Cheng 《PloS one》2014,9(7)
Developing a high-throughput method for the effecient selection of the highest producing cell is very important for the production of recombinant protein drugs. Here, we developed a novel transiently protein-anchored system coupled with fluorescence activated cell sorting (FACS) for the efficient selection of the highest producing cell. A furin cleavage peptide (RAKR) was used to join a human anti-epithelial growth factor antibody (αEGFR Ab) and the extracellular-transmembrane-cytosolic domains of the mouse B7-1 antigen (B7). The furin inhibitor can transiently switch secreted αEGFR Ab into a membrane-anchored form. After cell sorting, the level of membrane αEGFR Ab-RAKR-B7 is proportional to the amount of secreted αEGFR Ab in the medium. We further selected 23 αEGFR Ab expressing cells and demonstrated a high correlation (R2 = 0.9165) between the secretion level and surface expression levels of αEGFR Ab. These results suggested that the novel transiently protein-anchored system can easily and efficiently select the highest producing cells, reducing the cost for the production of biopharmaceuticals. 相似文献
88.
Anthony OHare Daniel Balaz David M. Wright Carl McCormick Stanley McDowell Hannah Trewby Robin A. Skuce Rowland R. Kao 《PLoS computational biology》2021,17(6)
Multi-host pathogens are particularly difficult to control, especially when at least one of the hosts acts as a hidden reservoir. Deep sequencing of densely sampled pathogens has the potential to transform this understanding, but requires analytical approaches that jointly consider epidemiological and genetic data to best address this problem. While there has been considerable success in analyses of single species systems, the hidden reservoir problem is relatively under-studied. A well-known exemplar of this problem is bovine Tuberculosis, a disease found in British and Irish cattle caused by Mycobacterium bovis, where the Eurasian badger has long been believed to act as a reservoir but remains of poorly quantified importance except in very specific locations. As a result, the effort that should be directed at controlling disease in badgers is unclear. Here, we analyse densely collected epidemiological and genetic data from a cattle population but do not explicitly consider any data from badgers. We use a simulation modelling approach to show that, in our system, a model that exploits available cattle demographic and herd-to-herd movement data, but only considers the ability of a hidden reservoir to generate pathogen diversity, can be used to choose between different epidemiological scenarios. In our analysis, a model where the reservoir does not generate any diversity but contributes to new infections at a local farm scale are significantly preferred over models which generate diversity and/or spread disease at broader spatial scales. While we cannot directly attribute the role of the reservoir to badgers based on this analysis alone, the result supports the hypothesis that under current cattle control regimes, infected cattle alone cannot sustain M. bovis circulation. Given the observed close phylogenetic relationship for the bacteria taken from cattle and badgers sampled near to each other, the most parsimonious hypothesis is that the reservoir is the infected badger population. More broadly, our approach demonstrates that carefully constructed bespoke models can exploit the combination of genetic and epidemiological data to overcome issues of extreme data bias, and uncover important general characteristics of transmission in multi-host pathogen systems. 相似文献
89.
Claudia T Guimaraes Christiano C Simoes Maria Marta Pastina Lyza G Maron Jurandir V Magalhaes Renato CC Vasconcellos Lauro JM Guimaraes Ubiraci GP Lana Carlos FS Tinoco Roberto W Noda Silvia N Jardim-Belicuas Leon V Kochian Vera MC Alves Sidney N Parentoni 《BMC genomics》2014,15(1)
Background
Aluminum (Al) toxicity is an important limitation to food security in tropical and subtropical regions. High Al saturation on acid soils limits root development, reducing water and nutrient uptake. In addition to naturally occurring acid soils, agricultural practices may decrease soil pH, leading to yield losses due to Al toxicity. Elucidating the genetic and molecular mechanisms underlying maize Al tolerance is expected to accelerate the development of Al-tolerant cultivars.Results
Five genomic regions were significantly associated with Al tolerance, using 54,455 SNP markers in a recombinant inbred line population derived from Cateto Al237. Candidate genes co-localized with Al tolerance QTLs were further investigated. Near-isogenic lines (NILs) developed for ZmMATE2 were as Al-sensitive as the recurrent line, indicating that this candidate gene was not responsible for the Al tolerance QTL on chromosome 5, qALT5. However, ZmNrat1, a maize homolog to OsNrat1, which encodes an Al3+ specific transporter previously implicated in rice Al tolerance, was mapped at ~40 Mbp from qALT5. We demonstrate for the first time that ZmNrat1 is preferentially expressed in maize root tips and is up-regulated by Al, similarly to OsNrat1 in rice, suggesting a role of this gene in maize Al tolerance. The strongest-effect QTL was mapped on chromosome 6 (qALT6), within a 0.5 Mbp region where three copies of the Al tolerance gene, ZmMATE1, were found in tandem configuration. qALT6 was shown to increase Al tolerance in maize; the qALT6-NILs carrying three copies of ZmMATE1 exhibited a two-fold increase in Al tolerance, and higher expression of ZmMATE1 compared to the Al sensitive recurrent parent. Interestingly, a new source of Al tolerance via ZmMATE1 was identified in a Brazilian elite line that showed high expression of ZmMATE1 but carries a single copy of ZmMATE1.Conclusions
High ZmMATE1 expression, controlled either by three copies of the target gene or by an unknown molecular mechanism, is responsible for Al tolerance mediated by qALT6. As Al tolerant alleles at qALT6 are rare in maize, marker-assisted introgression of this QTL is an important strategy to improve maize adaptation to acid soils worldwide.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-153) contains supplementary material, which is available to authorized users. 相似文献90.
Mycena kentingensis, a new luminous mushroom, was discovered in the tropical forest of Kenting National Park in Taiwan. The pileus of M. kentingensis is 3–8 mm in diameter and emits green light in the dark. The dorsal surface of the pileus is covered with short and white spines. The lamellae are nearly free. The stipe is puberulous with a white basal disc about 2 mm broad. Cheilocystidia are clavate to obpyriform, 16–40?×?4–8 μm, and have dense excrescences on the upper half or two-thirds of the cell. The pileus lacks cherocyte, and the stipe lacks caulocystidium. To further identify the species by the DNA barcode method, the internal transcribed spacer (ITS) DNA sequence of M. kentingensis was amplified by polymerase chain reaction, sequenced, and searched for in the GenBank. The hit with the maximum score was an uncultured fungus clone KFRI2121 (accession number HQ662846) with 88 % sequence identity. For those ITS sequences associated with Latin binominal names in the GenBank, the hit with the maximum score was Mycena stylobates with 87 % sequence identity. Phylogenetic analyses by Bayesian and maximum likelihood methods showed that M. kentingensis is close to M. stylobates and M. adscendens. To develop its culture method, mycelia of M. kentingensis were isolated. The optimal temperature for mycelial growth on potato-dextrose agar (PDA) medium was 24 °C. Commercial compost with the addition of 20 % rice bran and 50 % water was appropriate for fruit-body formation. The new species of Mycena kentingensis brings the total of luminous fungi in the world to 74 species. 相似文献