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41.
Xanthomonas albilineans, the causative agent of leaf scald disease (LSD), colonizes the vascular system of sugarcane (Saccharum spp. hybrids). In this study X. albilineans strains from 28 countries were differentiated by using two methods of amplified fragment length polymorphism (AFLP). In the manual procedure, AFLP reactions were performed on 57 X. albilineans strains and after selective amplification using radiolabelled primers, the resulting products were separated using polyacrylamide gel electrophoresis. The autoradiographs were analyzed using GelCompar version 4.1 software (Applied Maths) to construct dendograms from similarity matrices. Fluorescent AFLP (FAFLP) was also employed on 52 X. albilineans strains using three fluorescently labelled primer combinations (automated AFLP). The FAFLP data was converted to a binary format using the Genemapper Software 3.7 (Applied Biosystems). Thereafter, dendograms were generated using the NTSYSpc. Software (USA). Distinct AFLP profiles were produced for the majority of the strains and were found to be useful in differentiating X. albilineans strains from various geographical locations. Fingerprints unique to each strain were reproducibly obtained and may be used to create a database for use in the identification of the various X. albilineans strains. It can be also concluded from the results obtained that the FAFLP has considerable technical advantages compared with the manual AFLP and also that the FAFLP is more sensitive than AFLP using radiolabelled primers in differentiating X. albilineans.  相似文献   
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A simple and efficient method for the synthesis of optically active γ-azidoalcohols is described. The lipase catalyzed kinetic resolutions of acetates of γ-azidoalcohols in aqueous as well as organic media have been studied. The enantiomerically pure γ-azidoalcohols obtained by the kinetic resolution in high enantiopurity have been utilized towards the synthesis of enantiomeric pairs of anti-depressant drugs, fluoxetine and duloxetine.  相似文献   
43.
Hemolin, a member of the immunoglobulin protein superfamily, functions in Lepidoptera as an opsonin in defence against potential pathogens and seems to play a role in tissue morphogenesis. We show that hemolin gene is expressed in several organs of Galleria mellonella larvae, including the nervous system and the silk glands. The expression in the silk glands of the wandering larvae and their isolated abdomens is enhanced within 6 h after an injection of bacteria, lipopolysaccharides, or peptidoglycans. The magnitude of silk gland response to bacterial challenge is similar to that seen in the fat body. A profound rise of hemolin expression without bacterial inoculation occurs in the silk glands of isolated abdomens when they are induced to pupate by a topical application of 20-hydroxyecdysone (20E). The induction of pupation is associated with silk gland programming for disintegration by apoptosis and phagocytosis. Administration of a juvenile hormone agonist prevents pupation and abolishes the stimulatory 20E effect on the hemolin expression. Hemolin protein can be immunodetected in the silk glands as well as in the spun-out cocoon silk. The results suggest that silk glands are a component of the insect immune system and that hemolin may mark the apoptic cells for the elimination by hemocytes.  相似文献   
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Lessertia frutescens L., commonly known as cancer-bush, is a medicinally reputed plant species indigenous to southern Africa. Field leaf extracts of this species are known to exhibit many curative properties. However, little is known about the bioactive compounds that are present in in vitro leaf extracts and seed extracts. The objective of this study was to verify the presence of and quantify l-canavanine, gamma amino butyric acid (GABA), arginine and d-pinitol in the seeds, field leaves and in vitro leaves of L. frutescens using gas and liquid chromatography. Methanolic extracts of in vitro leaves, field leaves and seeds were used. MRM chromatograms were recorded for l-canavanine and arginine using tandem mass spectrometry. GC chromatograms were recorded for GABA and d-pinitol using gas chromatography. d-Pinitol was found to be most abundant and was 14.75 and 18.17 mg/g in in vitro and field leaf extracts respectively, followed by GABA (7.29 and 3.48 mg/g), arginine (7.08 and 0.35 mg/g) and l-canavanine (0.55 and 0.08 mg/g). In the seed extracts, GABA content was found to be the highest (1.69 mg/g) followed by l-canavanine (0.37 mg/g), then d-pinitol (0.25 mg/g), and arginine (0.02 mg/g). In vitro leaves had higher quantities of all compounds, except for d-pinitol. This study therefore highlights the potential of bulking in vitro leaves for the extraction of the medicinal compounds, l-canavanine and GABA.  相似文献   
46.
Heat stroke (HS) is a serious civilian and military health issue. Due to the limited amount of experimental data available in humans, this study was conducted on a mouse mathematical model fitted on experimental data collected from mice under HS conditions, with the assumption there is good agreement among mammals. Core temperature (T(c)) recovery responses in a mouse model consist of hypothermia and delayed fever during 24 h of recovery that represent potential biomarkers of HS severity. The objective of this study was to develop a simulation model of mouse T(c) responses and identify optimal treatment windows for HS recovery using a three-dimensional predictive heat transfer simulation model. Several bioenergetic simulation variables, including nonlinear metabolic heat production (W/m3), temperature-dependent convective heat transfer through blood mass perfusion (W/m3), and activity-related changes in circadian T(c) were used for model simulation. The simulation results predicted the experimental data with few disparities. Using this simulation model, we tested a series of ambient temperature treatment strategies to minimize hypothermia and delayed fever to accelerate HS recovery. Using a genetic algorithm, we identified eight time segments (ambient temperature = 27, 30, 31, 29, 28, 28, 27, 26°C) of 110 min total duration that optimized HS recovery in our model simulation.  相似文献   
47.
A general mathematical framework has been proposed in this work for scheduling of a multiproduct and multipurpose facility involving manufacturing of biotech products. The specific problem involves several batch operations occurring in multiple units involving fixed processing time, unlimited storage policy, transition times, shared units, and deterministic and fixed data in the given time horizon. The different batch operations are modeled using state‐task network representation. Two different mathematical formulations are proposed based on discrete‐ and continuous‐time representations leading to a mixed‐integer linear programming model which is solved using General Algebraic Modeling System software. A case study based on a real facility is presented to illustrate the potential and applicability of the proposed models. The continuous‐time model required less number of events and has a smaller problem size compared to the discrete‐time model. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1221–1230, 2014  相似文献   
48.
Nicotinamide N-methyltransferase (NNMT) has been linked to obesity and diabetes. We have identified a novel nicotinamide (NA) analog, compound 12 that inhibited NNMT enzymatic activity and reduced the formation of 1-methyl-nicotinamide (MNA), the primary metabolite of NA by ~80% at 2?h when dosed in mice orally at 50?mg/kg.  相似文献   
49.
The air mycoflora of six indoor environments in Madras city (India) has been investigated by sampling air with an Andersen sampler and a Burkard personal sampler. Forty-eight species assignable to 24 genera were recorded by Andersen sampler. Spores belonging to 14 genera in addition toPenicillium andAspergillus were identified from Burkard trap slides. Species ofAspergillus, Penicillium, Mucor andRhizopus were most frequently isolated in considerable numbers. As a single genusAspergillus ranked first followed byPenicillium at some sites, andCladosporium at some other sites. The predominance ofPenicillium andAspergillus was also confirmed by Burkard trap data. Spores belonging toGanoderma, Nigrospora, Epicoccum, andTetraploa were recorded only by Burkard sampler, thereby suggesting the necessity of using two complimentary spore traps, cultural and non-cultural, in any aerobiological investigation.  相似文献   
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