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Objective: A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling oftetrapep-tide units Boc-Leu-Pro-Trp-Leu-Ome and Boc-Ile-Ala-Ala-Gly-Ome after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment.Methods: Solution phase technique was adopted for the synthesis of cyclooctapeptide--sarcodactylamide.Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz.Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-Ome and Ala-Gly-Ome.Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method.The structure of synthesized cyclopolypeptide was elucidated by FTIR,1H NMR,13C NMR,FABMS spectral data and elemental analysis.The newly synthesized peptide was evaluated for dif-ferent pharmacological activities including antimicrobial,anthelmintic and cytotoxic activities.Results: Synthesis of sarcodac-tylamide was accomplished with >78% yield utilizing dicyclohexylcarbodiimide (DCC) as coupling agent.Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines,in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis,Pontoscotex corethruses and Eudrilus sp.Moreover,cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa,in comparison to standard drugs griseofulvin and ciprofloxacin.Conclusion: Solution phase technique employing DCC and triethylamine (TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide.N-methyl morpholine (NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine. 相似文献
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Kiran Hasija 《Indian journal of clinical biochemistry : IJCB》2002,17(1):12-19
Changes in erythrocyte membrane glycoproteins during, leukaemia were investigated in one hundred patients. Control group contained
normal ones. The total protein and protein bound total carbohydrates (neutral sugars) in the glycoproteins extracted from
the erythrocyte membrane showed significant reduction in total protein and protein bound total carbohydrates before radiotherapy.
However, after the radiotherapy there was further reduction in total protein by 10.41% whereas there was increase in total
carbohydrates by 9.98%. Qualitative analysis reveals that with the help of lectins one can pin point the sugars which appear
or disappear due to leukaemia. The test could be of a diagnostic value. 相似文献
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Kiran?SarvabhotlaEmail author Prasad?Pingali Vasudeva?Varma 《Information Retrieval》2011,14(3):337-353
With the growth of social media, document sentiment classification has become an active area of research in this decade. It
can be viewed as a special case of topical classification applied only to subjective portions of a document (sources of sentiment).
Hence, the key task in document sentiment classification is extracting subjectivity. Existing approaches to extract subjectivity
rely heavily on linguistic resources such as sentiment lexicons and complex supervised patterns based on part-of-speech (POS)
information. This makes the task of subjective feature extraction complex and resource dependent. In this work, we try to
minimize the dependency on linguistic resources in sentiment classification. We propose a simple and statistical methodology
called review summary (RSUMM) and use it in combination with well-known feature selection methods to extract subjectivity.
Our experimental results on a movie review dataset prove the effectiveness of the proposed methodology. 相似文献
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Information use is defined as the application of acquired and transmitted information in the decision making of an organization at the strategic and tactical levels. The purpose of the research is to investigate how information use architecture impacts information load and usability at the operational level of manufacturing where machines, humans and the production processes are information users. A new approach to information load is introduced which takes all the characteristics of information use (tacit, mechanical, paper and digitized) and possibilities of users (machine, operator and process) into consideration. Information use nodes are conceptualized building blocks for information use architecture which impact information load and usability. The results suggest that information use load is sensitive to information encoding/decoding. A combination of the federated and integrated information use architectures tends to result in a low information use load and can become a strategic tool for waste reduction. How information usability relates to load varies depending on the usability characteristic in view. The major conclusion is that a holistic approach to information systems includes the consideration of information use architecture which is an important factor in the management of information load and usability at the operational level. 相似文献
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Fahd Kiran Miah Shah J. Ahmed Khandakar Venkatraman Sitalakshmi Miao Yuan 《Education and Information Technologies》2021,26(4):4027-4048
Education and Information Technologies - This paper proposes an integrated research framework that takes advantage of the similarities of design science research (DSR) and Design-based research... 相似文献
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Animating critical action learning: process-based leadership and management development 总被引：3，自引：3，他引：0
Increasing attention is focusing on the value of critical approaches to enhancing leadership and management development processes. This paper examines how a critical action learning perspectives can be harnessed to produce valuable learning and development through critically reflective practise. Critical action learning approaches not only explore underlying power and control issues, but actively engage in an examination of political and cultural processes affecting leadership development. The aims of this paper are to explore approaches to critical action learning, to elucidate its principal features, to highlight how it can be applied in leadership and management development contexts and, finally, to illuminate some of the complexities and challenges of working with critical action learning in practice. 相似文献
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Anuradha Bharosay Vivek Vikram Bharosay Kiran Saxena Meena Varma 《Indian journal of clinical biochemistry : IJCB》2018,33(2):178-183
This study was undertaken to evaluate the role of serum neuron specific enolase (NSE) in prediction of disability and neurological worsening in hypertensive ischemic cerebrovascular stroke. 80 hypertensive ischemic stroke patients diagnosed by a neurologist as per WHO definition along with radiological findings suggestive of cerebrovascular stroke and differentiating from hemorrhagic stroke and 60 controls having essential hypertension coming to hospital because of regular checkup or headache but with no neurological disease were included in the study. Neurological disability was assessed by NIHSS at the time of admission (within 72 h from the onset of stroke) and on 7th day after admission and cases were categorized into mild, moderate and severe disability. Venous blood samples were drawn within 72 h from the onset of symptoms. The samples were processed as per the laboratory protocol. The serum NSE samples were analyzed using an enzyme immunoassay based on the sandwich technique. We observed raised serum NSE in hypertensive ischemic stroke (17.4 ± 5.4 ng/ml) with significant association between different hypertensive groups than in hypertensive controls (9.1 ± 0.75 ng/ml). Greater degree of disability was observed in hypertensive stroke patients with raised serum NSE and hypertensive patients with mean serum NSE level of 22.9 ± 3.6 ng/ml and dyslipidemia had greater probability of neurological worsening as compared to those with mean serum NSE level of 12.7 ± 1.2 ng/ml. Serum NSE levels can serve as a peripheral indicator of neuronal damage and assist in the prediction of disability and clinical outcome in hypertensive cerebrovascular ischemic stroke patients. 相似文献