Gene encoder: a feature selection technique through unsupervised deep learning-based clustering for large gene expression data

© 2020, Springer-Verlag London Ltd., part of Springer Nature. Cancer is a severe condition of uncontrolled cell division that results in a tumor formation that spreads to other tissues of the body. Therefore, the development of new medication and treatment methods for this is in demand. Classification of microarray data plays a vital role in handling such situations. The relevant gene selection is an important step for the classification of microarray data. This work presents gene encoder, an unsupervised two-stage feature selection technique for the cancer samples’ classification. The first stage aggregates three filter methods, namely principal component analysis, correlation, and spectral-based feature selection techniques. Next, the genetic algorithm is used, which evaluates the chromosome utilizing the autoencoder-based clustering. The resultant feature subset is used for the classification task. Three classifiers, namely support vector machine, k-nearest neighbors, and random forest, are used in this work to avoid the dependency on any one classifier. Six benchmark gene expression datasets are used for the performance evaluation, and a comparison is made with four state-of-the-art related algorithms. Three sets of experiments are carried out to evaluate the proposed method. These experiments are for the evaluation of the selected features based on sample-based clustering, adjusting optimal parameters, and for selecting better performing classifier. The comparison is based on accuracy, recall, false positive rate, precision, F-measure, and entropy. The obtained results suggest better performance of the current proposal

A Practical Catalyst-Free Synthesis of 6-Amino-4 Alkyl/Aryl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-carbonitrile in Aqueous Medium

A completely green and improved method for the synthesis of 6-amino-4-aryl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-carbonitriles by a four-component reaction of a mixture of ethyl acetoacetate, hydrazine hydrate, aldehyde, and malononitrile in boiling water is reported. Similar synthesis starting from aliphatic aldehydes was carried out in water: ethanol (1 : 1) at reflux temperature without using any catalyst

Synthesis of Polyfunctionalized 4H-Pyrans

Amberlyst A21 catalyzed one-pot three-component coupling of aldehyde and malononitrile with active methylene compounds such as acetylacetone and ethyl acetoacetate for the synthesis of pharmaceutically important polyfunctionalized 4H-pyrans has been reported. Simple experimental procedure, no chromatographic purification, no hazardous organic solvents, easy recovery and reusability of the catalyst, and room temperature reaction conditions are some of the highlights of this protocol for the synthesis of pharmaceutically relevant focused libraries

Cooperative catalysis of silica gel with physisorbed water in the synthesis of bis(indolyl)alkanes

877-883Silica gel catalyzed synthesis of bis(indolyl)alkane from the reaction of aldehyde and indole has been carried out. The fact that the reaction rate is slow with dried silica gel than that with moist silica gel suggest possible co-operative catalysis by water and silica gel to affect the transformation with excellent yield upon grinding at room temperature. This method for the synthesis of bis(indolyl)alkane has been found to be much better than many silica supported acid catalysts, since it requires no heating and has a much shorter reaction-time

Secondary laryngeal tuberculosis revisited

Introduction: Laryngeal tuberculosis is often misdiagnosed and is a highly contagious public health problem. The changing pattern of the clinical involvement of this disease poses a diagnostic challenge. The authors report four cases of laryngeal tuberculosis encountered in a short span of one month. Materials and Methods: All the four patients who presented to us with hoarseness had underlying active lesions in the lung. In spite of that they presented with mainly laryngeal symptoms and a multitude of findings on laryngeal examination. A diagnosis could be established owing to a high index of clinical suspicion, and due consideration given to the chest findings and positive sputum examination. The patients showed an excellent response to antituberculous therapy. Results and Conclusions: This study underlines the varied nature of laryngeal tuberculosis and the importance of addressing the hoarseness of a patient at the earliest, for the prompt diagnosis of this infectious condition

Amberlyst A21 Catalyzed Chromatography-Free Method for Multicomponent Synthesis of Dihydropyrano[2,3‑<i>c</i>]pyrazoles in Ethanol

Amberlyst A21 was found to be an extremely efficient catalyst for synthesis of a series of 6-amino-4-alkyl/aryl-3-methyl-2,4-dihydropyrano­[2,3-<i>c</i>]­pyrazole-carbonitriles by a four-component reaction of a mixture of ethyl acetoacetate, hydrazine hydrate, aldehyde, and malononitrile in ethanol at room temperature. The catalytic efficiency of Amberlyst A21 was compared with some other resin-bound free and anionic bases in order to ascertain the best catalyst for the said conversion. The catalyst was found to work extremely well also for acyclic/cyclic ketones to give corresponding dihydropyrano­[2,3-<i>c</i>]­pyrazoles or their spirocyclic variants. Easy recovery of the catalyst and its reusability, room temperature reaction conditions, short reaction time, excellent yields, no chromatographic purification, and evasion of environmentally hazardous solvents in the entire reaction process may make this protocol very useful for academia and industry