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21.
Cylindrospermopsis raciborskii is a central bloom-forming cyanobacteria. However, despite its ecological significance, little is known of its interactions with the phages that infect it. Currently, only a single sequenced genome of a Cylindrospermopsis-infecting phage is publicly available. Here we describe the isolation and characterization of Cr-LKS3, a second phage infecting Cylindrospermopsis. Cr-LKS3 is a siphovirus with a higher genome similarity to prophages within heterotrophic bacteria genomes than to any other cyanophage/cyano-prophage, suggesting that it represents a novel cyanophage group. The function, order and orientation of the 72 genes in the Cr-LKS3 genome are highly similar to those of Escherichia virus Lambda (hereafter Lambda), despite the very low sequence similarity between these phages, showing high evolutionary convergence despite the substantial difference in host characteristics. Similarly to Lambda, the genome of Cr-LKS3 contains various genes that are known to be central to lysogeny, suggesting it can enter a lysogenic cycle. Cr-LKS3 has a unique ability to infect a host with a dramatically different GC content, without carrying any tRNA genes to compensate for this difference. This ability, together with its potential lysogenic lifestyle shed light on the complex interactions between C. raciborskii and its phages.  相似文献   
22.
Carboxylic acids play an important role in both aerobic and anaerobic metabolic pathways of both the snail and the parasite. Monitoring the effects of infection by schistosome on Biomphalaria alexandrina carboxylic acids metabolic profiles represents a promising additional source of information about the state of metabolic system. We separated and quantified pyruvic, fumaric, malic, oxalic, and acetic acids using ion-suppression reversed-phase high performance liquid chromatography (HPLC) to detect correlations between these acids in both hemolymph and digestive gland gonad complex (DGG's) samples in a total of 300 B. alexandrina snails (150 infected and 150 controls) at different stages of infection. The results showed that the majority of metabolite pairs did not show significant correlations. However, some high correlations were found between the studied acids within the control group but not in other groups. More striking was the existence of reversed correlations between the same acids at different stages of infection. Some possible explanations of the underlying mechanisms were discussed. Ultimately, however, further data are required for resolving the responsible regulatory events. These findings highlight the potential of metabolomics as a novel approach for fundamental investigations of host-pathogen interactions as well as disease surveillance and control.  相似文献   
23.
Four series of pyrazolylbenzenesulfonamide derivatives were synthesized and evaluated for their anti-inflammatory activity using cotton pellet induced granuloma and carrageenan-induced rat paw edema bioassays. Moreover, COX-1 and COX-2 inhibitory activity, ulcerogenic effect and acute toxicity were also determined. Furthermore, the target compounds were screened for their in-vitro antimicrobial activity against Eischerichia coli, Staphylococcus aureus and Candida albicans. Compounds 4-(3-Phenyl-4-cyano-1H-pyrazol-1-yl)benzenesulfonamide 9a and 4-(3-Tolyl-4-cyano-1H-pyrazol-1-yl)benzenesulfonamide 9b were not only found to be the most active dual anti-inflammatory antimicrobial agents in the present study with good safety margin and minimal ulcerogenic effect but also exhibited good selective inhibitory activity towards COX-2. A docking pose for 9a and 9b separately in the active site of the human COX-2 enzyme was also obtained. Therefore, these compounds would represent a fruitful matrix for the development of dual anti-inflammatory antimicrobial candidates with remarkable COX-2 selectivity.  相似文献   
24.
Xanthine oxidase (XO), purified from buttermilk was subjected to modification with N-phenylmaleimide, p-toluene-sulfonyl chloride, and 2-mercaptobenzimidazole. Spectrophotometric monitoring of the enzyme before and after treatment with these modifiers are presented. The results show that the interaction of XO with the modifiers was accompained by a change in UV absorption, as compared with untreated enzyme. The data indicate that these modifiers caused conformational changes in the polypeptide chain of milk XO due to interaction of these modifiers with sulfahydryl and/or hydroxyl groups. Moreover, the modifiers induce uptake inhibition of milk XO and appeared to be dependant upon either the concentration or incubation time.  相似文献   
25.
Precise identification of infarcted myocardial tissue is of importance in diagnostic and interventional cardiology. A three-dimensional, catheter-based endocardial electromechanical mapping technique was used to assess the ability of local endocardial impedance in delineating the exact location, size, and border of canine myocardial infarction. Electromechanical mapping of the left ventricle was performed in a control group (n = 10) and 4 wk after left anterior descending coronary artery ligation (n = 10). Impedance, bipolar electrogram amplitude, and endocardial local shortening (LS) were quantified. The infarcted area was compared with the corresponding regions in controls, revealing a significant reduction in impedance values [infarcted vs. controls: 168.8 +/- 11. 7 and 240.7 +/- 22.3 Omega, respectively (means +/- SE), P < 0.05] bipolar electrogram amplitude (1.8 +/- 0.2 mV, 4.4 +/- 0.7 mV, P < 0. 05), and LS (-2.36 +/- 1.6%, 11.9 +/- 0.9%, P < 0.05). The accuracy of the impedance maps in delineating the location and extent of the infarcted region was demonstrated by the high correlation with the infarct area (Pearson's correlation coefficient = 0.942) and the accurate identification of the infarct borders in pathology. By accurately defining myocardial infarction and its borders, endocardial impedance mapping may become a clinically useful tool in differentiating healthy from necrotic myocardial tissue.  相似文献   
26.
BACKGROUND: The next clinical frontier in the therapeutics of ischemic heart disease may involve the development and delivery of specific molecules and cells into the myocardium. The aim of the present study was to evaluate the efficiency and safety of the MyoStar injection catheter (Biosense-Webster Inc.) that has recently been developed to deliver molecules and cells to the myocardium. The 8 Fr (110 cm length) catheter comprises a navigation sensor with a 27 gauge needle at the distal tip. METHODS: Mouse myogenic cells (C2) were delivered to a tissue culture dish through different modalities: a standard laboratory pipette, a syringe needle (27 gauge) and the injection catheter. The cells were counted and monitored for growth and differentiation in the tissue culture immediately after delivery and two, three and six days later. Cells that were injected through a regular syringe needle or through the injection catheter demonstrated the same capacity to proliferate in tissue culture up to six days. RESULTS: The behavior of the cells in culture (fusion) was identical for the cells delivered to the tissue culture by a pipette or by the injection catheter. CONCLUSION: The results of the present study indicate that delivery of cells through the MyoStar injection catheter is a method with no significant loss or adverse effects to the cells along the path of the catheter. The catheter, which possesses both injection and navigation capabilities, can be used to deliver cell therapy to patients with ischemic heart disease.  相似文献   
27.
The amino acid pattern — free and bound — ofCaulerpa prolifera plants was studied. Maximum values for the total free amino acids were observed during periods of minimum growth, while minimum values occurred during periods of maximum growth of the alga. The bound amino acids showed a reverse trend.  相似文献   
28.
The human genetic diseases associated with many factors, one of these factors is the non-synonymous Single Nucleotide Variants (nsSNVs) cause single amino acid change with another resulting in protein function change leading to disease. Many computational techniques have been released to expect the impacts of amino acid alteration on protein function and classify mutations as pathogenic or neutral. Here in this article, we assessed the performance of eight techniques; FATHMM, SIFT, Provean, iFish, Mutation Assessor, PANTHER, SNAP2, and PON- P2 using a VaribenchSelectedPure dataset of 2144 pathogenic variants and 3777 neutral variants extracted from the free standard database “Varibench.” The first five techniques achieve (45.60–83.75) % specificity, (52.64–94.13) % sensitivity, (51.00–88.90) % AUC, and (49.76–88.24) % ACC on whole dataset, while all eight techniques achieve (36.54–77.88) % specificity, (50.00–75.00) % sensitivity, (51.00–76.40) % AUC, and (25.00–77.78) % ACC on random sample dataset. We also created a Meta classifier (CSTJ48) that combines FATHMM, iFish, and Mutation Assessor. It registers 96.33% specificity, 86.07% sensitivity, 91.20% AUC, and 91.89 ACC. By comparing the results, it's clear that FATHMM gives the highest performance over the seven individual techniques, where it achieves 83.75% and 77.88% specificity, 94.13%, and 75.00% sensitivity, 88.90% and 76.40% AUC, and 88.24% and 77.78% ACC on whole and random sample dataset, respectively. Also, the launched Meta classifier (CSTJ48) is outperforming over all the eight individual tools that compared here.  相似文献   
29.
The effect of different light intensities on growth, and the amino acid, fat and sugar concentrations ofCaulerpa prolifera (Foerskal) Lamouroux were studied. The results showed that 2,500 lux was the optimum light intensity for growth coupled with a minimum in total free amino acids and maximum in peptides, total soluble sugars and total lipids. Any deviations above or below the optimum light intensity caused a drop in all components studied.  相似文献   
30.
Spodoptera frugiperda is a highly polyphagous migratory lepidopteran pest species. It causes infestation in crops leading to the severe crop losses. Being a new invasive parasite, its susceptibility to insecticides needs to be explored; and therefore, there is an urgent need to develop the potent insecticides for the effective control of this insect pest. To attain the crop sustainability, the antifeedant, toxicity and nutritional effects on larvae of Spodoptera frugiperda were studied with six mono- and eight bis- substituted chalcones. The antifeedant activity was calculated when 50% of the larvae control ate 50% of the diet through the FR factor. Toxicity was assessed through larval, pupal mortality and the emergence of adults and nutritional effects with consumption rates (IC), growth (GR) and consumption efficiency (EIC). The bis-chalcones 6b, 6e, 6f and 6h caused lethal effect on S. frugiperda in the first larval stages, being 6b the most toxic (85%). Adults who survived showed malformations and decreased size, which led to death. The larvae fed with aggregate in the bis-chalcones diet: 6b, 6e and 6f had the highest percentage of intake and the poorest conversion of nutrient absorption (ECI), which suggests that the larva metabolizes food for energy and results in a decrease of growth and death in early stages. Bis-chalcones showed more toxicity than mono-chalcones and 6b causes the most toxic and dietary change.  相似文献   
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