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81.
Zhe Liang Viktor Demko Robert C. Wilson Kenneth A. Johnson Rafi Ahmad Pierre‐François Perroud Ralph Quatrano Sen Zhao Kamran Shalchian‐Tabrizi Marisa S. Otegui Odd‐Arne Olsen Wenche Johansen 《The Plant journal : for cell and molecular biology》2013,75(5):742-754
DEK1, the single calpain of land plants, is a member of the ancient membrane bound TML–CysPc–C2L calpain family that dates back 1.5 billion years. Here we show that the CysPc–C2L domains of land plant calpains form a separate sub‐clade in the DEK1 clade of the phylogenetic tree of plants. The charophycean alga Mesostigma viride DEK1‐like gene is clearly divergent from those in land plants, suggesting that a major evolutionary shift in DEK1 occurred during the transition to land plants. Based on genetic complementation of the Arabidopsis thaliana dek1‐3 mutant using CysPc–C2L domains of various origins, we show that these two domains have been functionally conserved within land plants for at least 450 million years. This conclusion is based on the observation that the CysPc–C2L domains of DEK1 from the moss Physcomitrella patens complements the A. thaliana dek1‐3 mutant phenotype. In contrast, neither the CysPc–C2L domains from M. viride nor chimeric animal–plant calpains complement this mutant. Co‐evolution analysis identified differences in the interactions between the CysPc–C2L residues of DEK1 and classical calpains, supporting the view that the two enzymes are regulated by fundamentally different mechanisms. Using the A. thaliana dek1‐3 complementation assay, we show that four conserved amino acid residues of two Ca2+‐binding sites in the CysPc domain of classical calpains are conserved in land plants and functionally essential in A. thaliana DEK1. 相似文献
82.
Daniel W. Nebert Kjell Wikvall Walter L. Miller 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1612)
There are 18 mammalian cytochrome P450 (CYP) families, which encode 57 genes in the human genome. CYP2, CYP3 and CYP4 families contain far more genes than the other 15 families; these three families are also the ones that are dramatically larger in rodent genomes. Most (if not all) genes in the CYP1, CYP2, CYP3 and CYP4 families encode enzymes involved in eicosanoid metabolism and are inducible by various environmental stimuli (i.e. diet, chemical inducers, drugs, pheromones, etc.), whereas the other 14 gene families often have only a single member, and are rarely if ever inducible or redundant. Although the CYP2 and CYP3 families can be regarded as largely redundant and promiscuous, mutations or other defects in one or more genes of the remaining 16 gene families are primarily the ones responsible for P450-specific diseases—confirming these genes are not superfluous or promiscuous but rather are more directly involved in critical life functions. P450-mediated diseases comprise those caused by: aberrant steroidogenesis; defects in fatty acid, cholesterol and bile acid pathways; vitamin D dysregulation and retinoid (as well as putative eicosanoid) dysregulation during fertilization, implantation, embryogenesis, foetogenesis and neonatal development. 相似文献
83.
H. William Johansen 《欧洲藻类学杂志》2013,48(1):79-86
Clearcut differences exist between the reproductive organs of Corallina and Jania. Fully formed spermatangial conceptacles in Corallina have low ceillings and pronounced beaks whereas in Jania they have high ceilings and lack beaks. Fusion cells in carposporophytic conceptacles are thin and broad in the former genus and thick and narrow in the latter. Tetrasporangial conceptacles have less capacity in Jania than in Corallina and the fertile areas in young conceptacles cover a smaller area. Haliptylon is changed from group to generic status and Corallina subulata is transferred to this genus. Haliptylon is characterised by conceptacles similar in all known respects to those of Jania, but the branching is pinnate, as in Corallina. From the available evidence it appears possible that organisms having Corallina-type conceptacles diverged phylogenetically long ago from those having Jania-type conceptacles. 相似文献
84.
85.
Morten Bo Johansen Jose M. G. Izarzugaza S?ren Brunak Thomas Nordahl Petersen Ramneek Gupta 《PloS one》2013,8(7)
We have developed a sequence conservation-based artificial neural network predictor called NetDiseaseSNP which classifies nsSNPs as disease-causing or neutral. Our method uses the excellent alignment generation algorithm of SIFT to identify related sequences and a combination of 31 features assessing sequence conservation and the predicted surface accessibility to produce a single score which can be used to rank nsSNPs based on their potential to cause disease. NetDiseaseSNP classifies successfully disease-causing and neutral mutations. In addition, we show that NetDiseaseSNP discriminates cancer driver and passenger mutations satisfactorily. Our method outperforms other state-of-the-art methods on several disease/neutral datasets as well as on cancer driver/passenger mutation datasets and can thus be used to pinpoint and prioritize plausible disease candidates among nsSNPs for further investigation. NetDiseaseSNP is publicly available as an online tool as well as a web service: http://www.cbs.dtu.dk/services/NetDiseaseSNP 相似文献
86.
Label‐free analysis of human cerebrospinal fluid addressing various normalization strategies and revealing protein groups affected by multiple sclerosis 下载免费PDF全文
Jill A. Opsahl Marc Vaudel Astrid Guldbrandsen Elise Aasebø Vincent Van Pesch Diego Franciotta Kjell‐Morten Myhr Harald Barsnes Magnus Berle Øivind Torkildsen Ann C. Kroksveen Frode S. Berven 《Proteomics》2016,16(7):1154-1165
The aims of the study were to: (i) identify differentially regulated proteins in cerebrospinal fluid (CSF) between multiple sclerosis (MS) patients and non‐MS controls; (ii) examine the effect of matching the CSF samples on either total protein amount or volume, and compare four protein normalization strategies for CSF protein quantification. CSF from MS patients (n = 37) and controls (n = 64), consisting of other noninflammatory neurological diseases (n = 50) and non neurological spinal anesthetic subjects (n = 14), were analyzed using label‐free proteomics, quantifying almost 800 proteins. In total, 122 proteins were significantly regulated (p < 0.05), where 77 proteins had p‐value <0.01 or AUC value >0.75. Hierarchical clustering indicated that there were two main groups of MS patients, those with increased levels of inflammatory response proteins and decreased levels of proteins involved in neuronal tissue development (n = 30), and those with normal protein levels for both of these protein groups (n = 7). The main subgroup of controls clustering with the MS patients showing increased inflammation and decreased neuronal tissue development were patients suffering from chronic fatigue. Our data indicate that the preferable way to quantify proteins in CSF is to first match the samples on total protein amount and then normalize the data based on the median intensities, preferably from the CNS‐enriched proteins. 相似文献
87.
Purpose
This study aimed to investigate the mid- to long-term outcomes of cervical disc arthroplasty (CDA) versus anterior cervical discectomy and fusion (ACDF) for the treatment of 1-level or 2-level symptomatic cervical disc disease.Methods
Medline, Embase, and the Cochrane Central Register of Controlled Trials databases were searched to identify relevant randomized controlled trials that reported mid- to long-term outcomes (at least 48 months) of CDA versus ACDF. All data were analyzed by Review Manager 5.3 software. The relative risk (RR) and 95% confidence intervals (CIs) were calculated for dichotomous variables. The weighted mean difference (WMD) and 95%CIs were calculated for continuous variables. A random effect model was used for heterogeneous data; otherwise, a fixed effect model was used.Results
Eight prospective randomized controlled trials (RCTs) were retrieved in this meta-analysis, including 1317 and 1051 patients in CDA and ACDF groups, respectively. Patients after an ACDF had a significantly lower rate of follow-up than that after CDA. Pooled analysis showed patients in CDA group achieved significantly higher rates of overall success, Neck Disability Index (NDI) success, neurological success and significantly lower rates of implant/surgery-related serious adverse events and secondary procedure compared with that in ACDF group. The long-term functional outcomes (NDI, Visual Analog Scale (VAS) neck and arm pain scores, the Short Form 36 Health Survey physical component score (SF-36 PCS)), patient satisfaction and recommendation, and the incidence of superior adjacent segment degeneration also favored patients in CDA group with statistical difference. Regarding inferior adjacent segment degeneration, patients in CDA group had a lower rate without statistical significance.Conclusions
This meta-analysis showed that cervical disc arthroplasty was superior over anterior discectomy and fusion for the treatment of symptomatic cervical disc disease in terms of overall success, NDI success, neurological success, implant/surgery-related serious adverse events, secondary procedure, functional outcomes, patient satisfaction and recommendation, and superior adjacent segment degeneration. 相似文献88.
Francisco Gómez Real Laura Pérez Barrionuevo Karl Franklin Eva Lindberg Randi Jacobsen Bertelsen Bryndís Benediktsdóttir Bertil Forsberg Thorarinn Gislason Rain J?gi Ane Johannessen Ernst Omenaas Eirunn Saure Vivi Schlünssen Trude Duelien Skorge Kjell Torén Antonio Pérez Saavedra ?istein Svanes Anne Nordrehaug ?str?m Christer Janson Cecilie Svanes 《PloS one》2016,11(1)
Background
There is little knowledge about how oral and respiratory health is interrelated even though the mucosa of the oral cavity and airways constitutes a continuum and the exposures to these are partly similar.Aims
To investigate whether gum bleeding is related to asthma, respiratory symptoms and self-reported COPD.Methods
A postal questionnaire including questions about respiratory and oral health was sent to general population samples in seven Northern European centres. In 13,409 responders, gum bleeding when brushing teeth was reported always/often by 4% and sometimes by 20%. Logistic regressions accounted for age, smoking, educational level, centre and gender. Effects of BMI, cardio-metabolic diseases, early life factors, gastro-oesophageal reflux, dental hygiene, nasal congestion, and asthma medication were addressed.Results
Gum bleeding always/often was significantly associated with ≥3 asthma symptoms (OR 2.58, 95% CI 2.10–3.18), asthma (1.62 [1.23–2.14]) and self-reported COPD (2.02 [1.28–3.18]). There was a dose-response relationship between respiratory outcomes and gum bleeding frequency (≥3 symptoms: gum bleeding sometimes 1.42 [1.25–1.60], often/always 2.58 [2.10–3.18]), and there was no heterogeneity between centres (pheterogeneity = 0.49). None of the investigated risk factors explained the associations. The observed associations were significantly stronger among current smokers (pinteraction = 0.004).Conclusions
A consistent link between gum bleeding and obstructive airways disease was observed, not explained by common risk factors or metabolic factors. We speculate that oral pathogens might have unfavourable impact on the airways, and that the direct continuity of the mucosa of the oral cavity and the airways reflects a pathway that might provide novel opportunities for interventions. 相似文献89.
90.
Pre‐adapting parasitic phages to a pathogen leads to increased pathogen clearance and lowered resistance evolution with Pseudomonas aeruginosa cystic fibrosis bacterial isolates 下载免费PDF全文
V‐P. Friman D. Soanes‐Brown P. Sierocinski S. Molin H. K. Johansen M. Merabishvili J‐P. Pirnay D. De Vos A. Buckling 《Journal of evolutionary biology》2016,29(1):188-198
Recent years have seen renewed interest in phage therapy – the use of viruses to specifically kill disease‐causing bacteria – because of the alarming rise in antibiotic resistance. However, a major limitation of phage therapy is the ease at with bacteria can evolve resistance to phages. Here, we determined whether in vitro experimental coevolution can increase the efficiency of phage therapy by limiting the resistance evolution of intermittent and chronic cystic fibrosis Pseudomonas aeruginosa lung isolates to four different phages. We first pre‐adapted all phage strains against all bacterial strains and then compared the efficacy of pre‐adapted and nonadapted phages against ancestral bacterial strains. We found that evolved phages were more efficient in reducing bacterial densities than ancestral phages. This was primarily because only 50% of bacterial strains were able to evolve resistance to evolved phages, whereas all bacteria were able to evolve some level of resistance to ancestral phages. Although the rate of resistance evolution did not differ between intermittent and chronic isolates, it incurred a relatively higher growth cost for chronic isolates when measured in the absence of phages. This is likely to explain why evolved phages were more effective in reducing the densities of chronic isolates. Our data show that pathogen genotypes respond differently to phage pre‐adaptation, and as a result, phage therapies might need to be individually adjusted for different patients. 相似文献