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101.
Streptoverticillium kashmirense AF1 with the ability to degrade a natural polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was isolated from municipal sewage sludge by soil burial technique. The PHBV film was degraded by the action of extracellular enzymes secreted by the microorganisms. Degradation of PHBV was evident by the formation of clear zones of hydrolysis on the polymer containing mineral salt agar plates. The extent of PHBV degradation increased up to 30 days of incubation. Maximum production of PHBV depolymerase was observed both at pH 8 and pH 7, 45 °C, 1% substrate concentration and in the presence of lactose as an additional carbon source. Two types of extracellular PHBV depolymerases were purified fromS. kashmirense AF1 by gel permeation chromatography using Sephadex G-75. The molecular weights of the two proteins were found to be 35 and 45 kDa approximately, as determined by SDS-PAGE. The results of the Sturm test also showed more CO2 production as a result of PHBV degradation, in the test as compared to control. The present findings indicated the degradation capabilities ofS. kashmirense AF1.  相似文献   
102.
Calligonolides A (1) and B (2), two new butanolides, and a new steroidal ester, 3, have been isolated from the whole plant of Calligonum polygonoides, together with four known compounds, tetracosan-4-olide, beta-sitosterol and its glucoside, and ursolic acid. Their structures were elucidated by spectroscopic and mass-spectrometric studies. Compounds 1-3 showed moderate inhibitory potential against lipoxygenase from soybean.  相似文献   
103.
We recently reported the disruption of the inner mitochondrial membrane peptidase 2-like (IMMP2L) gene by a chromosomal breakpoint in a patient with Gilles de la Tourette syndrome (GTS). In the present study we sought to identify genetic variation in IMMP2L, which, through alteration of protein function or level of expression might contribute to the manifestation of GTS. We screened 39 GTS patients, and, due to the localization of IMMP2L in the critical region for the autistic disorder (AD) locus on chromosome 7q (AUTS1), 95 multiplex AD families; however, no coding mutations were found in either GTS or AD patients. In addition, no parental-specific expression of IMMP2L was detected in somatic cell hybrids containing human chromosome 7 and human cell lines carrying a maternal uniparental disomy for chromosome 7 (mUPD7). Despite the fact that no deleterious mutations in IMMPL2 (other than the inverted duplication identified previously) were identified in either GTS or AD, this gene cannot be excluded as a possible rare cause of either disorder.  相似文献   
104.

Surface plasmon polariton (SPP) waves are the most extensively studied waves among various types of surface waves because they are easy to excite and have been used in many optical applications particularly for plasmonic communication, sensing, and harvesting solar energy. In all these applications, especially on-chip plasmonic communication, scattering can be an important issue to deal with. Therefore, this paper aimed to theoretically inspect the scattering pattern of SPP waves from a perfect electric conductor (PEC) cylindrical scatterer. The cylindrical wave approach is used to solve the scattering problem by a cylindrical object placed below a metallic layer. The scattering is investigated thoroughly by changing the size of the scatterer and its distance from the interface along which the SPP wave is excited. As the size of the scatterer increases, the scattering increases significantly. On the other hand, when the distance of the scatterer from the interface is increased, the scattered field becomes small. Two-dimensional field maps are produced for the incident angle at which SPP is excited. Numerical results are also presented for other incident angles to make a comparison. Furthermore, the forward and backward far-fields are significantly enhanced if the SPP wave is scattered in comparison with when the SPP wave is not present.

  相似文献   
105.
Cluster Computing - HPC or super-computing clusters are designed for executing computationally intensive operations that typically involve large scale I/O operations. This most commonly involves...  相似文献   
106.
Plant and Soil - Abiotic stresses are threatening wheat productivity across the globe, which is often associated with nutrient deficiencies. Zinc (Zn) is involved in many physiological processes of...  相似文献   
107.
Chiral considerations are found to be very much relevant in various aspects of forensic toxicology and pharmacology. In forensics, it has become increasingly important to identify the chirality of doping agents to avoid legal arguments and challenges to the analytical findings. The scope of this study was to develop an liquid chromatography–mass spectrometry (LCMS) method for the enantiomeric separation of typical illicit drugs such as ephedrines (ie, 1S,2R(+)‐ephedrine and 1R,2S(?)‐ephedrine) and pseudoephedrine (ie, R,R(?)‐pseudoephedrine and S,S(+)‐pseudoephedrine) by using normal phase chiral liquid chromatography–high‐resolution mass spectrometry technique. Results show that the Lux i‐amylose‐1 stationary phase has very broad and balancing‐enantio‐recognition properties towards ephedrine analogues, and this immobilized chiral stationary phase may offer a powerful tool for enantio‐separation of different types of pharmaceuticals in the normal phase mode. The type of mobile phase and organic modifier used appear to have dramatic influences on separation quality. Since the developed method was able to detect and separate the enantiomers at very low levels (in pico grams), this method opens easy access for the unambiguous identification of these illicit drugs and can be used for the routine screening of the biological samples in the antidoping laboratories.  相似文献   
108.
Epidemiology and molecular typing of Candida isolates from burn patients   总被引:2,自引:0,他引:2  
This study, spread over a span of 2 years describes Candida infections in burn patients of an Indian hospital. A total of 220 burn patients were monitored and Candida could be isolated from 138 patients. A total of 228 different Candida species were obtained from various body locations of these patients. Species identification revealed that Candida albicans was the most predominant (45) followed by Candida tropicalis(33), Candida glabrata (13.5), C. parapsilosis (4), C. krusei (2.75) and C. kefyr (1.75). DNA fingerprinting of all C. albicans isolates was done by using CARE-2 probe. Fingerprinting analyses of all the C. albicans strains revealed that strains collected from different patients were different. It is noteworthy that patients with disseminated candidiasis had a similar, but unique strain isolated from all body locations, suggesting a possibility that commensal isolates might be turning pathogenic. Taken together, this is probably the first ever detailed survey of Candidainfections in burn patients in India and is expected to lead to better clinical management of this group of patients.  相似文献   
109.
Arp2/3 is a negative regulator of growth cone translocation   总被引:6,自引:0,他引:6  
Arp2/3 is an actin binding complex that is enriched in the peripheral lamellipodia of fibroblasts, where it forms a network of short, branched actin filaments, generating the protrusive force that extends lamellipodia and drives fibroblast motility. Although it has been assumed that Arp2/3 would play a similar role in growth cones, our studies indicate that Arp2/3 is enriched in the central, not the peripheral, region of growth cones and that the growth cone periphery contains few branched actin filaments. Arp2/3 inhibition in fibroblasts severely disrupts actin organization and membrane protrusion. In contrast, Arp2/3 inhibition in growth cones minimally affects actin organization and does not inhibit lamellipodia protrusion or de novo filopodia formation. Surprisingly, Arp2/3 inhibition significantly enhances axon elongation and causes defects in growth cone guidance. These results indicate that Arp2/3 is a negative regulator of growth cone translocation.  相似文献   
110.
Paeoninol and paeonin C, oligostilbene and monoterpene galactoside, have been isolated from the methanolic extract of the fruits of Paeonia emodi. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition, 4-hydroxybenzoic acid 3, gallic acid 4 and methyl gallate 5 have also been reported for the first time from this species. Compounds 1 and 2 have displayed potent inhibitory potential against enzyme lipoxygenase in a concentration-dependent fashion with the IC(50) values 0.77 and 99.5 microM, along with ABTS(.+) radical quenching activity with IC(50) values of 147.5 and 498.2 microM, respectively.  相似文献   
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