1,753 research outputs found
Molecular population genetics and gene expression analysis of duplicated CBF genes of Arabidopsis thaliana
<p>Abstract</p> <p>Background</p> <p><it>CBF/DREB </it>duplicate genes are widely distributed in higher plants and encode transcriptional factors, or CBFs, which bind a DNA regulatory element and impart responsiveness to low temperatures and dehydration.</p> <p>Results</p> <p>We explored patterns of genetic variations of <it>CBF1, -2</it>, and -<it>3 </it>from 34 accessions of <it>Arabidopsis thaliana</it>. Molecular population genetic analyses of these genes indicated that <it>CBF2 </it>has much reduced nucleotide diversity in the transcriptional unit and promoter, suggesting that <it>CBF2 </it>has been subjected to a recent adaptive sweep, which agrees with reports of a regulatory protein of <it>CBF2</it>. Investigating the ratios of K<sub>a</sub>/K<sub>s </sub>between all paired <it>CBF </it>paralogus genes, high conservation of the AP2 domain was observed, and the major divergence of proteins was the result of relaxation in two regions within the transcriptional activation domain which was under positive selection after <it>CBF </it>duplication. With respect to the level of <it>CBF </it>gene expression, several mutated nucleotides in the promoters of <it>CBF3 </it>and <it>-1 </it>of specific ecotypes might be responsible for its consistently low expression.</p> <p>Conclusion</p> <p>We concluded from our data that important evolutionary changes in <it>CBF1, -2</it>, and -<it>3 </it>may have primarily occurred at the level of gene regulation as well as in protein function.</p
NOVA, a Noncommutative-ring Based Unbalanced Oil and Vinegar Signature Scheme with Key-randomness Alignment
In this paper, we propose a noncommutative-ring based unbalanced oil and vinegar signature scheme with key-randomness alignment: NOVA (Noncommutative Oil and Vinegar with Alignment). Instead of fields or even commutative rings, we show that noncommutative rings can be used for algebraic cryptosystems. At the same or better level of security requirement, NOVA has a much smaller public key than UOV (Unbalanced Oil and Vinegar), which makes NOVA practical in most situations. We use Magma to actually implement and give a detailed security analysis against known major attacks
A Simple Noncommutative UOV Scheme
In this paper, we propose a simple noncommutative-ring based UOV signature scheme with key-randomness alignment: Simple NOVA, which can be viewed as a simplified version of NOVA[48]. We simplify the design of NOVA by skipping the perturbation trick used in NOVA, thus shortens the key generation process and accelerates the signing and verification. Together with a little modification accordingly, this alternative version of NOVA is also secure and may be more suitable for practical uses. We also use Magma to actually implement and give a detailed security analysis against known major attacks
MetaSquare: An integrated metadatabase of 16S rRNA gene amplicon for microbiome taxonomic classification
MOTIVATION: Taxonomic classification of 16S ribosomal RNA gene amplicon is an efficient and economic approach in microbiome analysis. 16S rRNA sequence databases like SILVA, RDP, EzBioCloud and HOMD used in downstream bioinformatic pipelines have limitations on either the sequence redundancy or the delay on new sequence recruitment. To improve the 16S rRNA gene-based taxonomic classification, we merged these widely used databases and a collection of novel sequences systemically into an integrated resource.
RESULTS: MetaSquare version 1.0 is an integrated 16S rRNA sequence database. It is composed of more than 6 million sequences and improves taxonomic classification resolution on both long-read and short-read methods.
AVAILABILITY AND IMPLEMENTATION: Accessible at https://hub.docker.com/r/lsbnb/metasquare_db and https://github.com/lsbnb/MetaSquare.
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online
Acute immune thrombocytopenic purpura in an adolescent with 2009 novel H1N1 influenza A virus infection
AbstractAlthough both leukopenia and thrombocytopenia are not uncommon hematological findings among patients with novel 2009 H1N1 influenza virus infection, immune thrombocytopenic purpura has rarely been shown to be associated with this novel influenza A infection. Here, we describe a previously healthy adolescent who presented with fever, influenza-like symptoms and acute onset of generalized petechiae and active oral mucosa bleeding on the third day of his illness. Severe leukopenia and thrombocytopenia were found. There was neither malignancy nor blast cells found by bone marrow aspiration. Real-time reverse transcriptase polymerase chain reaction was positive for novel 2009 H1N1 influenza infection. Novel influenza-associated atypical immune thrombocytopenic purpura was diagnosed. The patient recovered uneventfully after oseltamivir and methylprednisolone therapy
Fluoroquinolones are associated with delayed treatment and resistance in tuberculosis: a systematic review and meta-analysis
SummaryBackgroundCurrent guidelines for treating community-acquired pneumonia recommend the use of fluoroquinolones for high-risk patients. Previous studies have reported controversial results as to whether fluoroquinolones are associated with delayed diagnosis and treatment of pulmonary tuberculosis (TB) and the development of fluoroquinolone-resistant Mycobacterium tuberculosis. We performed a systematic review and meta-analysis to clarify these issues.MethodsThe following databases were searched through September 30, 2010: PubMed, EMBASE, CINAHL, Cochrane Library, Web of Science, BIOSIS Previews, and the ACP Journal Club. We considered studies that addressed the issues of delay in diagnosis and treatment of TB and the development of resistance.ResultsNine eligible studies (four for delays and five for resistance issues) were included in the meta-analysis from the 770 articles originally identified in the database search. The mean duration of delayed diagnosis and treatment of pulmonary TB in the fluoroquinolone prescription group was 19.03 days, significantly longer than that in the non-fluoroquinolone group (95% confidence interval (CI) 10.87 to 27.18, p<0.001). The pooled odds ratio of developing a fluoroquinolone-resistant M. tuberculosis strain was 2.70 (95% CI 1.30 to 5.60, p=0.008). No significant heterogeneity was found among studies in the meta-analysis.ConclusionsEmpirical fluoroquinolone prescriptions for pneumonia are associated with longer delays in diagnosis and treatment of pulmonary TB and a higher risk of developing fluoroquinolone-resistant M. tuberculosis
Food Supplement 20070721-GX May Increase CD34+ Stem Cells and Telomerase Activity
Few rejuvenation and antiaging markers are used to evaluate food supplements. We measured three markers in peripheral blood to evaluate the antiaging effects of a food supplement containing placental extract. Samples were evaluated for CD34+ cells, insulin-like growth factor 1 (IGF1), and telomerase activity, which are all markers related to aging. To control the quality of this food supplement, five active components were monitored. In total, we examined 44 individuals who took the food supplement from 1.2 months to 23 months; the average number of CD34+ cells was almost 6-fold higher in the experimental group compared with the control group. Food supplement intake did not change serum IGF1 levels significantly. Finally, the average telomerase activity was 30% higher in the subjects taking this food supplement. In summary, our results suggest that the placental extract in the food supplement might contribute to rejuvenation and antiaging
Effects of Lower Limb Cycling Training on Different Components of Force and Fatigue in Individuals With Parkinson’s Disease
The strength of lower extremity is important for individuals to maintain balance and ambulation functions. The previous studies showed that individuals with Parkinson’s disease suffered from fatigue and strength loss of central origin. The purpose of this study was to investigate the effect of lower extremities’ cycling training on different components of force and fatigue in individuals with Parkinson’s disease. Twenty-four individuals (13 males, 11 females, mean age: 60.58 ± 8.21 years) diagnosed with idiopathic Parkinson’s disease were randomized into training and control groups. The maximum voluntary contraction (MVC) force, voluntary activation level (VA), and twitch force of knee extensors were measured using a custom-made system with surface electrical stimulation. The general, central, and peripheral fatigue indexes (GFI, CFI, and PFI) were calculated after a fatiguing cycling protocol. Subjects received 8 weeks of low resistance cycling training (training group) or self-stretching (control group) programs. Results showed that MVC, VA, and twitch force improved (p \u3c 0.05) only in the training group. Compared to the baseline, central fatigue significantly improved in the training group, whereas peripheral fatigue showed no significant difference in two groups. The cycling training was beneficial for individuals with Parkinson’s disease not only in muscle strengthening but also in central fatigue alleviation. Further in-depth investigation is required to confirm the effect of training and its mechanism on central fatigue
Refractory gastric variceal bleeding secondary to splenic vein occlusion associated with abdominal lymphadenopathy
SummarySplenic vein occlusion caused by abdominal lymphadenopathy is rare. We herein present the case of a 80-year-old man with refractory isolated gastric variceal bleeding in the absence of pancreatic or liver disease. Left-sided portal hypertension was confirmed by angiography, and para-aortic lymphadenopathy compressing the splenic vein was identified by serial abdominal computed tomography. Endoscopic sclerosing therapy failed to treat the recurring gastric variceal hemorrhage. Therefore, splenectomy was suggested and the patient was successfully treated. The patient had been variceal bleeding free for 12 months since the surgery. In patients with isolated gastric varices but without advanced liver disease, a variety of diagnostic techniques should be attempted to elucidate the nature of portal hypertension, and left-sided portal hypertension should be suspected. For those cases in which endoscopic treatment failed to treat refractory gastric variceal bleeding, splenectomy can be an effective option
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