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111.
Siva S. Panda Mohamed A. Ibrahim Said A. El‐Feky Alan R. Katritzky 《Journal of peptide science》2013,19(2):110-117
Nα‐Boc‐Nim‐(4‐toluenesulfonyl‐l ‐histidylbenzotriazole) enables convenient acylation of N‐, O‐, S‐, and C‐nucleophiles with no detectable racemization. We report efficient syntheses of novel histidine‐containing di‐, tri‐, and tetra‐peptides and models for the preparation of potentially biologically active histidine N‐, O‐, S‐, and C‐conjugates. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
112.
Solid state production of polygalacturonase and xylanase by Trichoderma species using cantaloupe and watermelon rinds 总被引:1,自引:0,他引:1
Saleh A. Mohamed Abdulrahman L. Al-Malki Jalaluddin A. Khan Saleh A. Kabli Saleh M. Al-Garni 《Journal of microbiology (Seoul, Korea)》2013,51(5):605-611
Different solid state fermentation (SSF) sources were tested such as cantaloupe and watermelon rinds, orange and banana peels, for the production of polygalacturonase (PG) and xylanase (Xyl) by Trichoderma harzianum and Trichoderma virens. The maximum production of both PG and Xyl were obtained by T. harzianum and T. virnes grown on cantaloupe and watermelon rinds, respectively. Time course, moisture content, temperature, pH, supplementation with carbon and nitrogen sources were optimized to achieve the maximum production of both PG and Xyl of T. harzianum and T. virens using cantaloupe and watermelon rinds, respectively. The maximum production of PG and Xyl of T. harzianum and T. virens was recorded at 4–5 days of incubation, 50–66% moisture, temperature 28–35°C and pH 6–7. The influence of supplementary carbon and nitrogen sources was studied. For T. harzianum, lactose enhanced PG activity from 87 to 120 units/g solid, where starch and maltose enhanced Xyl activity from 40 to 55–60 units/g solid for T. virnes. Among the nitrogen sources, ammonium sulphate, ammonium nitrate, yeast extract and urea increased PG activity from 90 to 110–113 units/g solid for T. harzianum. Similarly, ammonium chloride, ammonium sulphate and yeast extract increased Xyl activity from 45 to 55–70 units/g solid for T. virens. 相似文献
113.
Abdel‐Maaboud I. Mohamed Osama H. Abdelmageed Hesham Salem Dalia M. Nagy Mahmoud A. Omar 《Luminescence》2013,28(3):345-354
A validated simple and sensitive spectrofluorimetric method was developed for the determination of chlorpromazine hydrochloride, promethazine hydrochloride, trifluperazine hydrochloride, thioridazine hydrochloride, perazine maleate and oxomemazine. The method was based on condensation of malonic acid/acetic anhydride (MAA) under the catalytic effect of the tertiary amine moiety of the studied phenothiazines to provide a deep yellow to brown colour with green florescence. Relative fluorescence intensity of the products was measured at λexc 398 nm and λem 432 nm. Different variables affecting the reaction were studied and optimized. The method was successfully applied for the determination of the studied drugs in commercial dosage forms. The lower detection limits allowed the application of this method for the determination of the compounds in plasma as an example of a biological fluid. In addition, the method was considered specific for the determination of tertiary amines in the presence of primary and secondary amines; as a result, it was deemed suitable for the determination of the cited drugs in the presence of their degradation products resulting from N‐dealkylation or oxidation of the corresponding sulphoxides or sulphones. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
114.
Mohamed F. Abdel-Megeed Mohamed A. Saleh Youssef L. Aly Ibrahim M. Abdo 《Nucleosides, nucleotides & nucleic acids》2013,32(9-10):1985-1996
Abstract A series of some new acetylated S-glycosides of 2-thioxoquinazolin-4-ones, their thiono analogues and 3,1-benzothazin-2,4-dithione derivatives, including a D-glucose and a D-galactose derivatives and a D-xylose, and an L-arabinose derivatives have been synthesized. The conformation and configuration of these carbohydrate derivatives were determined by analysing their 1H and 13C NMR chemical shifts and coupling constants. The biological activity of these compounds has been studied. 相似文献
115.
Mohamed I. Elzagheid Mikko Oivanen Karel D. Klika Bryan C. N. M. Jones Richard Cosstick Harri Lönnberg 《Nucleosides, nucleotides & nucleic acids》2013,32(9):2093-2108
Abstract The course of hydrolysis of 3′-deoxy-3′-thioinosylyl-(3′ → 5′)-uridine (IspU) has been followed by HPLC over a wide pH-range. Two reactions of the internucleosidic thiophosphate linkage compete: (i) cleavage yielding thioinosine monophosphates and uridine, and (ii) isomerization to the 2′,5′-isomer of IspU. Under very acidic conditions, even acid-catalyzed depurination of the inosine moiety is observed. The stability of the thiophosphate linkage and the mechanisms of its rupture are discussed. 相似文献
116.
117.
Mohamed Abou-El-Enein Andy Römhild Daniel Kaiser Carola Beier Gerhard Bauer Hans-Dieter Volk Petra Reinke 《Cytotherapy》2013,15(3):362-383
Background aimsAdvanced therapy medicinal products (ATMP) have gained considerable attention in academia due to their therapeutic potential. Good Manufacturing Practice (GMP) principles ensure the quality and sterility of manufacturing these products. We developed a model for estimating the manufacturing costs of cell therapy products and optimizing the performance of academic GMP-facilities.MethodsThe “Clean-Room Technology Assessment Technique” (CTAT) was tested prospectively in the GMP facility of BCRT, Berlin, Germany, then retrospectively in the GMP facility of the University of California-Davis, California, USA. CTAT is a two-level model: level one identifies operational (core) processes and measures their fixed costs; level two identifies production (supporting) processes and measures their variable costs. The model comprises several tools to measure and optimize performance of these processes. Manufacturing costs were itemized using adjusted micro-costing system.ResultsCTAT identified GMP activities with strong correlation to the manufacturing process of cell-based products. Building best practice standards allowed for performance improvement and elimination of human errors. The model also demonstrated the unidirectional dependencies that may exist among the core GMP activities. When compared to traditional business models, the CTAT assessment resulted in a more accurate allocation of annual expenses. The estimated expenses were used to set a fee structure for both GMP facilities. A mathematical equation was also developed to provide the final product cost.ConclusionsCTAT can be a useful tool in estimating accurate costs for the ATMPs manufactured in an optimized GMP process. These estimates are useful when analyzing the cost-effectiveness of these novel interventions. 相似文献
118.
Ishan Agarwal Sayantan Biswas Aaron M. Bauer Eli Greenbaum Todd R. Jackman Anslem De Silva 《分类学与生物多样性》2013,11(5):427-439
We evaluated the status of 16 of 22 recognized Sri Lankan Cnemaspis Strauch species, and flagged overlooked diversity with two mitochondrial (cyt b & ND2) and two nuclear markers (RAG1 & PDC) totalling 2829 base pairs. A fossil-calibrated timetree and sampling of other South Asian Cnemaspis provide insights into the diversification of the genus in peninsular India and Sri Lanka. Phylogenetic analyses consistently inferred two broad clades within South Asian Cnemaspis, with Sri Lankan species in two clades, which we call the podihuna and kandiana clades. Each Sri Lankan clade as a whole is sister to Indian taxa and nested within Indian lineages. Cnemaspis modigliani Das from Indonesia is a member of the kandiana clade. This suggests a minimum of two dispersal events between India and Sri Lanka and one between Sri Lanka/India and South-east Asia. South Asian Cnemaspis date back to at least the Eocene, in Sri Lanka to the early Miocene, with late Miocene diversification in the kandiana clade. All but one of the named species we sampled is likely to be valid, and 10 divergent unnamed lineages may warrant specific recognition. A resolution of Sri Lankan Cnemaspis taxonomy will require thorough sampling and the use of both morphological and molecular data. 相似文献
119.
The release of prothoracicotropic hormone, PTTH, or its blockade is the major endocrine switch regulating the developmental channel either to metamorphosis or to pupal diapause in the Chinese silk moth, Antheraea pernyi. We have cloned cDNAs encoding two types of serotonin receptors (5HTRA and B). 5HTRA-, and 5HTRB-like immunohistochemical reactivities (-ir) were colocalized with PTTH-ir in two pairs of neurosecretory cells at the dorsolateral region of the protocerebrum (DL). Therefore, the causal involvement of these receptors was suspected in PTTH release/synthesis. The level of mRNA5HTRB responded to 10 cycles of long-day activation, falling to 40% of the original level before activation, while that of 5HTRA was not affected by long-day activation. Under LD 16:8 and 12:12, the injection of dsRNA5HTRB resulted in early diapause termination, whereas that of dsRNA5HTRA did not affect the rate of diapause termination. The injection of dsRNA5HTRB induced PTTH accumulation, indicating that 5HTRB binding suppresses PTTH synthesis also. This conclusion was supported pharmacologically; the injection of luzindole, a melatonin receptor antagonist, plus 5th inhibited photoperiodic activation under LD 16:8, while that of 5,7-DHT, induced emergence in a dose dependent fashion under LD 12:12. The results suggest that 5HTRB may lock the PTTH release/synthesis, maintaining diapause. This could also work as diapause induction mechanism. 相似文献
120.