Virtual screening, molecular docking, molecular dynamics and quantum chemical studies on (2-methoxy-4-prop-2-enylphenyl) N-(2-methoxy-4-nitrophenyl) carbamate: a novel inhibitor of hepatocellular carcinoma

HDAC protein is associated with hepatocellular carcinoma. Different medicinal plants were selected for this study to analyze the inhibitory efficacy against the target protein, HDAC. Using virtual screening, we filtered out the best compounds, and molecular docking (XP) was carried out for the top compounds which filtered out. The molecular docking results showed that the title compound (2-methoxy-4-prop-2-enylphenyl) N-(2-methoxy-4-nitrophenyl) carbamate (MEMNC) has the highest docking score of about -7.7 kcal/mol against the targeted protein histone deacetylase (HDAC) compared with the other selected phytocompounds. From the molecular dynamics analysis, the RMSD and RMSF plots depicted the overall stability of the protein-ligand complex. Toxicity properties show the acceptable range of various kinds of toxicity that were predicted using the ProTox-II server. In addition, DFT quantum chemical and physicochemical properties of the MEMNC molecule were reported. Initially, the molecular structure of the MEMNC molecule was optimized and harmonic vibrational frequencies were calculated using DFT/B3LYP method with a cc-pVTZ basis set using Gaussian 09 program. The calculated vibrational wavenumber values were assigned based on Potential Energy Distribution calculations using the VEDA 4.0 program and correlated well with the previous literature values. The molecule has bioactivity as a result of intramolecular charge transfer interactions, as demonstrated by frontier molecular orbital analysis. Molecular electrostatic potential surface and Mulliken atomic charge distribution analyses validate the reactive sites of the molecule. Thus, the title compound can be used as a potential inhibitor of HDAC protein, which paves the way for designing novel drugs to treat Hepatocellular carcinoma.Communicated by Ramaswamy H. Sarma.

Porous chitosan-infused graphitic carbon nitride nanosheets for potential microbicidal and photo-catalytic efficacies

Supply of safe drinking water is a high-risk challenge faced internationally. Hybrid technologies involving nanomaterials can offer possible solutions to this research involving natural biopolymers. Porous chitosan with a high specific surface area has promising properties but its use as a membrane component in water purification is still rarely reported. Graphitic carbon nitride (g-C₃N₄) is a carbon nitride allotrope with a graphene-like layered structure that gifts unfamiliar physicochemical properties due to the presence of s-triazine fragments. It is a metal-free semiconductor with a band gap of ~2.7 eV to ~3.7 eV; which shows better visible light-activated photocatalyst properties. This work aims at synthesizing graphitic carbon nitride-biopolymer composite and exploring its properties in the field of wastewater treatment. The samples were synthesized via a soft chemical process with urea, as the source material. The flake-like morphology is displayed in the microstructural SEM image. The composition of the material was analyzed using EDS. Thermogram shows that the material is stable up to 500 °C and also confirms the formation of graphitic carbon nitride. In XRD spectra the intensity reduction shows the chitosan inclusion at the nitride site. The band gap of the prepared material was identified to be 2.3, 2.4 eV. The structural properties were analyzed using Fourier Transform Infrared Spectrometer and Raman spectroscopy. FTIR spectra and Raman spectra indicate the stretching vibration modes of CN and CN heterocycles and chitosan inclusion in the carbon nitride network. The photocatalytic activity was done in sunlight and a UV lamp with different dyes for doped and undoped g-C₃N₄. The doped (Porous/Non-porous chitosan) g-C₃N₄ showed faster dye degradation in sunlight compared to UV light. A biomolecular interaction study was done using Bovine serum albumin. It shows the material interaction with the BSA protein. The anti-microbial activity was performed on the Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli by disk diffusion method, the chitosan doped g-C₃N₄ showed good inhibitions against bacterial growth. The current work reveals the impact of nanoscale chitosan nanostructures doped on the optical, microstructural, catalytic, and antimicrobial properties of g-C₃N₄ nanosheets. This work provides new research options for nanocomposite-based photocatalytic nanomaterial g-C₃N₄ so that the quality of contaminated water could be improved.

Targeting potential receptor molecules in non-small cell lung cancer (NSCLC) using in silico approaches

Introduction: Non-Small Cell Lung Cancer is the most prevalent type of cancer in lung cancer. Chemotherapy, radiation therapy, and other conventional cancer treatments have a low success rate. Thus, creating new medications is essential to halt the spread of lung cancer. Methods: In this study bioactive nature of lochnericine against Non-Small Cell Lung Cancer (NSCLC) was analyzed using various computational approaches such as quantum chemical calculations, molecular docking, and molecular dynamic simulation. Furthermore, the MTT assay shows the anti-proliferation activity of lochnericine. Results and Discussion: Using Frontier Molecular Orbital (FMO), the calculated band gap energy value associated with bioactive compounds and the molecule's potential bioactivity is confirmed. The H38 hydrogen atom and O1 oxygen atom in the molecule are effectively electrophilic, and potential nucleophilic attack sites were confirmed through analysis of the Molecular electrostatic potential surface. Furthermore, the electrons within the molecule were delocalized, which confers bioactivity on the title molecule and was authorized through Mulliken atomic charge distribution analysis. A molecular docking study revealed that lochnericine inhibits non-small cell lung cancer-associated targeted protein. The lead molecule and targeted protein complex were stable during molecular dynamics simulation studies till the simulation period. Further, lochnericine demonstrated remarkable anti-proliferative and apoptotic features against A549 lung cancer cells. The current investigation powerfully suggests that lochnericine is a potential candidate for lung cancer.

Molecular docking and dynamic simulations of Ocimum basilicum compounds against HCC and structural, vibrational, quantum, and chemical investigation of campesterol

Hepatocellular carcinoma (HCC) is a pervasive type of liver malignant growth and the third-driving reason for disease-related overall mortality with an expanding pervasiveness worldwide. Besides, no successful treatment can be utilized on patients with the cutting-edge or metastatic illness. Some of the natural therapeutics are paved the way for developing potential inhibitors for many types of cancer. Ocimum basilicum is one of the most well-known herbs, which contains numerous therapeutic properties and is widely used for various health issues. This study focused on its valuable medicinal property against HCC via in silico approach. Bioactive constituents from O. basilicum is subjected to molecular docking and dynamics study for 100 ns against the HCC targets (FGFR1, FGFR2, FGFR3, and FGFR4), and the selected lead compounds showed better interactions, docking score, obeys Lipinski's rule of five, highest occupied molecular orbital, lowest unoccupied molecular orbital hypothesis, protein-complex stability throughout the simulation period and the pharmacophoric features were analysed. Out of selected seven compounds, Campesterol revealed its potential therapeutic activity (Docking score - FGFR1 - 8.59 Kcal/Mol, FGFR2 - 7.11 Kcal/Mol, FGFR3 - 10.53 Kcal/Mol and FGFR4 - 9.17 Kcal/Mol, respectively. And also, it maintains good stability with the targets without any fluctuations. So, we concluded our findings that Campesterol is considered as, such a promising and potential inhibitor for HCC.Communicated by Ramaswamy H. Sarma.

Classification of Effect on Real Estates in Mumbai During Covid-19

At the point when the global pandemic hit, we saw one of the greatest monetary accidents in late history. With crashes in the securities exchange and irregularities in all business sectors and ventures, one thing that never appears to change is the increment in worth of homes. This pandemic had made the land area take a significant misfortune. The sentiment scores of the real estate partners had arrived at an unequalled low score of 31. The crash of the real estate put many companies and brokers into bankruptcy. People stopped investing in real estate while others withdrew any sort of the ongoing investments. The conditions worsened with the second wave. The second wave, unlike the first, had a significantly higher death rate and spread very quickly instilling fear in the minds of the people. This became a factor in the huge economic crash that this pandemic has provided. The government has been desperately looking for measures to come back stronger but have failed. This called for research into this domain and start predictions with various models to help prepare for any foreseeing losses/crashes. Within the past 10 years, the housing market has gotten more and more modest with houses that used to be affordable being valued at absurdly high amounts. This increase in value has seen a reduction in home proprietorship percentage in proportion to populace of the country. Our project aims to project values for real estate in the absence of covid. The difference in values are analyzed and generalized. Furthermore, solutions to improve the current condition will also be given.

An anxious relationship between Autism Spectrum Disorder and Gut Microbiota: A tangled chemistry?

Autism spectrum disorder (ASD) is a serious multifactorial neurodevelopmental disorder often accompanied by strained social communication, repetitive behaviour, immune dysregulation, and gastrointestinal (GI) issues. Recent studies have recorded a link between dysbiosis in the gut microbiota (gm) and the primary stages of ASD. A bidirectional connection (also called microbiota-gut-brain-axis) exchanges information between the gut bacteria and central nervous system. When the homeostasis of the microenvironment of the gut is dysregulated, it causes oxidative stress, affecting neuronal cells and neurotransmitters, thereby causing neurodevelopmental disorders. Studies have confirmed a difference in the constitution of gut bacteria among ASD cases and their controls. Numerous studies on animal models of ASD have shown altered gm and its association with abnormal metabolite profile and altered behaviour phenotype. This process happens due to an abnormal metabolite production in gm, leading to changes in the immune system, especially in ASD. Hence, this review aims to question the current knowledge on gm dysbiosis and its related GI discomforts and ASD behavioural symptoms and shed light on the possible therapeutic approaches available to deal with this situation. Thereby, though it is understood that more research might be needed to prove an association or causal relationship between gm and ASD, therapy with the microbiome may also be considered as an effective strategy to combat this issue.

Screening and identification of potential inhibitor for visceral leishmaniasis (VL) through computational analysis

Aim

The aim of this investigation is to detect potential inhibitor for visceral leishmaniasis through computational analysis.

Background

Leishmaniasis is categorized as a vector born pathogenic infection prevalent in tropical, subtropical, and in Mediterranean zones spread by intra-macrophage protozoa. The clinical syndrome of leishmaniasis is divided into the following type’s namely cutaneous leishmaniasis, mucocutaneous leishmaniasis, visceral leishmaniasis, and dermal leishmaniasis. Trypanothione synthetase is a key enzyme involving in glutathione biosynthesis as well as hydrolysis. Trypanothione is one of the promising drug targets for parasites. Parasites are inimitable with concern to their dependence on trypanothione to regulate intracellular thiol-redox balance in fighting against oxidative stress and biochemical anxiety. However, trypanothione synthetase was presumed as the target therapeutic alternate in VL therapy.

Objective

The important objective of this current investigation is to identify or analyze the potential inhibitor for V. leishmaniasis through computational approaches which include virtual screening, molecular docking, ADME prediction, and molecular dynamic simulation.

Methods

An investigation was performed to develop a 3D protein structure, using computational screening among associated similar structured proteins from popular compound database banks such as Specs, Maybridge, and Enamine, to detect novel staging with a series of validation for emerging innovative drugs molecules. Modeled protein ligand complex was further analyzed to know the binding ability of the complex. Molecular dynamics were performed to ascertain its stability at 50 ns.

Results

Trypanothione synthetase overall ability in the outcome of series of analysis. Among three database compounds screened, the compound from the Specs database exhibited the better protein-ligand docking scores and fulfilled the drug-like properties through ADMET analysis, and the docked complexes had better stability throughout the simulation. Besides, the other two database leads fulfilled the pharmacological properties, and the complexes were stable in the simulation.

Conclusion

By analyzing the various compounds from different databases, we concluded that the Specs database compound exhibits potential activity against the target protein and is considered a promising inhibitor for trypanothione synthetase.

DeepCompNet: A Novel Neural Net Model Compression Architecture

The emergence of powerful deep learning architectures has resulted in breakthrough innovations in several fields such as healthcare, precision farming, banking, education, and much more. Despite the advantages, there are limitations in deploying deep learning models in resource-constrained devices due to their huge memory size. This research work reports an innovative hybrid compression pipeline for compressing neural networks exploiting the untapped potential of z-score in weight pruning, followed by quantization using DBSCAN clustering and Huffman encoding. The proposed model has been experimented with state-of-the-art LeNet Deep Neural Network architectures using the standard MNIST and CIFAR datasets. Experimental results prove the compression performance of DeepCompNet by 26x without compromising the accuracy. The synergistic blend of the compression algorithms in the proposed model will ensure effortless deployment of neural networks leveraging DL applications in memory-constrained devices.

The Current Understanding on Langerhans' Cells and Its Role in Oral Lesions

OBJECTIVE

Description of Langerhans' cells (LCs) as an important antigen-presenting cells responsible for detecting the antigens, recruiting T-cells, and thereby initiating the immune response. An adequate response of the mucosal immune system is essential to protect the mucosa against pathological conditions. Hence, a detailed review was planned about this unique antigen-presenting cell.

METHODS

A literature search of the electronic databases included the MEDLINE, EBSCOHOST, PUBMED, and hand searches of references retrieved were undertaken using the following MeSH terms "Langerhans cells," "LCs in Oral Lichen Planus," "Langerhans cell histiocytosis," "LCs and HIV," "LCs in Periodontitis."

RESULTS

LCs are present suprabasally in the epithelium of oral mucosa and in the epidermis of the skin. The role played by LCs though not fully elucidated, but several research studies indicate that these cells are involved in the pathogenesis of many oral diseases. In this article, the historical perspective, structure, function, origin, and phenotypic expressions of LCs are discussed in detail. The current understanding on the role of LCs in various oral lesions and its immunological characteristics are discussed.

CONCLUSION

LCs act as immune mediator cells, tumor cells, vectors of infected cells, and phagocytic cells. Further studies could bolster the knowledge about the role of Langerhans cells in the immune response of various oral diseases and thereby provide diagnostic tools and help for prognostic evaluation. This review illuminates the pivotal role of Langerhans cells and its immune surveillance as a "Sentinels" of the oral mucosa.

Luteolin in the Management of Type 2 Diabetes Mellitus

Diabetes is an increasing pandemic and several million people are affectedbythis disease worldwide. The treatment of diabetes includes lifestyle modifications, oral antidiabetic drugs and insulin. The chronic use of oral antidiabetic drugs produces undesirable side effects. Hence safe alternative medicines are always sought after. Plant phytochemicals are the best alternatives as they possess a wide spectrum of pharmacological activities. Flavonoids are an important class of phytocomponent which is commonly present in fruits and vegetables. Luteolin belongs toflavone class of flavonoid which has multiple health benefitslike antioxidant, antidiabetic,anti-inflammatory and anti-cancer properties. Luteolin mediates several pharmacological actions of which the role of luteolin in the treatment of diabetes is well studied. In thisreview, the use of flavonoids as antidiabetic agents is discussed, with special reference to luteolin.Luteolin mediates its anti-diabetic potential by maintaining blood glucose levels and improving the sensitivity of body cells to insulin and these mode of actions have been discussed here.

Structural, optical, dielectric and antibacterial studies of Mn doped Zn0.96Cu0.04O nanoparticles

Zn(0.96-x)Cu0.04Mn(x)O (0⩽x⩽0.04) nanoparticles were synthesized by sol-gel method. The X-ray diffraction pattern indicated that doping of Mn and Cu did not change the ZnO hexagonal wurtzite structure. The Mn doped nanoparticles had smaller average crystallite size than un-doped Zn0.96Cu0.04O nanoparticles due to the distortion in the host ZnO lattice. This distortion prevented the subsequent growth and hence the size reduced by Mn doping. The changes in lattice parameters, average crystallite size, peak position and peak intensity confirmed the Mn substitution in Zn-Cu-O lattice. The Mn and Cu co-doping increased the charge carrier density in ZnO nanoparticles which led to increase the dielectric constant. The dielectric constant also varied by depend the size of the nanoparticles. The change in morphology by Mn-doping was studied by transmission electron microscope. The optical absorption and band gap were changed with respect to both compositional and size effects. The band gap was initially increased from 3.65 to 3.73 eV at 1% of Mn doping, while decreasing trend in band gap was noticed for further increase of Mn. The band gap was decreased from 3.73 to 3.48 eV when Mn concentration was increased from 2% to 4%. Presence of chemical bonding and purity of the nanoparticles were confirmed by FTIR spectra. The antibacterial study revealed that that the antibacterial activity of Zn0.96Cu0.04O is enhanced by Mn doping.

Immunomorphological patterns of cervical lymph nodes in oral squamous cell carcinoma

Context:

Squamous cell carcinoma (SCC) comprises 80% of the cancers of the oral cavity. Metastases to the cervical lymph nodes affects prognosis. Studying lymph node reactivity may help to understand host immune reaction against the tumor and thus influence prognosis.

Aims:

This study observed patterns of lymph node reactivity, metastases and grades of metastases in cervical lymph nodes and compared them with the histopathology of the primary tumor.

Materials and Methods:

Lymph nodes from 30 patients of oral squamous cell carcinoma (OSCC) were taken. 10 of these were well-differentiated SCC (WDSCC), 10 moderately differentiated SCC (MDSCC) and 10 poorly differentiated SCC (PDSCC). Four immunomorphological patterns were observed: lymphocyte predominance, germinal centre predominance, mixed pattern (sinus histiocytosis) and unstimulated pattern.

Statistical Analysis Used:

Chi square test.

Results:

The predominant lymph node reactive patterns were germinal centre predominance (79.27%), unstimulated pattern (14.63%) and lymphocyte predominance (6.10%). Positive nodes showed invasion in the form of islands (57.14%), cords (39.29%) and total replacement pattern (3.57%). Tumor involvement in positive nodes showed grade 3 invasion, (53.57%), grade 2 invasion (26.79%), grade 4 invasion (17.86%) and grade 1 invasion (1.79%). Statistically significant association was found between:

Lymph node reactive pattern and histopathological grade of primary tumor. Higher numbers of germinal centre predominance lymph nodes were found in WDSCC and MDSCC

Histopathological grade of primary tumor and the grade of lymph node invasion

Conclusions:

Immuno-morphological assessment of draining lymph nodes reflects the immune status of the patient with respect to metastases. This may facilitate identification of high and low risk patients and help in planning appropriate therapy for the high-risk patients.

Ameloblastoma: Cytopathologic profile of 12 cases and literature review

Background:

Fine-needle aspiration cytology (FNAC) has been used as a diagnostic tool in evaluating suspected lesions. It shows a high diagnostic accuracy for diagnosing salivary gland lesions.

Aim:

The aim of this study was to highlight FNAC as an effective diagnostic tool in the presumptive diagnosis of ameloblastoma.

Materials and Methods:

A total of 12 cases of ameloblastoma sampled by FNAC retrieved from the archives of the Oral Pathology Department were retrospectively studied. The smears were alcohol-fixed and stained with hematoxylin and eosin. All the 12 cases of FNAC had subsequent corresponding surgical incisional biopsy or excision specimens.

Results:

Cytologically, seven cases were diagnosed as benign odontogenic tumor more in favor of ameloblastoma. All the 12 fine-needle aspiration cases were given a histopathologic work-up and diagnosed as ameloblastomas. Of these, the seven cytologically diagnosed benign odontogenic lesions were also confirmed to be ameloblastoma by both incisional biopsy as well as surgical excision.

Conclusion:

It was deduced from the above results that FNAC helps potentially in diagnosing ameloblastoma.

Molecular characterization of a proteolysis-resistant lipase from Bacillus pumilus SG2

Proteolysis-resistant lipases can be well exploited by industrial processes which employ both lipase and protease as biocatalysts. A proteolysis resistant lipase from Bacillus pumilus SG2 was isolated, purified and characterized earlier. The lipase was resistant to native and commercial proteases. In the present work, we have characterized the lip gene which encodes the proteolysis-resistant lipase from Bacillus pumilus SG2. The parameters and structural details of lipase were analysed. The lip gene consisted of 650 bp. The experimental molecular weight of SG2 lipase was nearly double that of its theoretical molecular weight, thus suggesting the existence of the functional lipase as a covalent dimer. The proteolytic cleavage sites of the lipase would have been made inaccessible by dimerisation, thus rendering the lipase resistant to protease.

Comparison of routine decalcification methods with microwave decalcification of bone and teeth

INTRODUCTION

The microwave oven has been used quite often for tissue processing, but there are very few studies describing its use in decalcification of bone or teeth. In this study we have attempted to decalcify bone and teeth using a microwave oven and compare the process and results with conventional decalcification methods.

AIMS AND OBJECTIVES

The objectives of the study were to determine and compare routine decalcification with microwave decalcification of bone and teeth using 5% nitric acid, 5% formic acid, and 14% ethylenediaminetetraacetic acid (EDTA) with respect to speed of decalcification, preservation of tissue structure and staining efficacy.

MATERIALS AND METHODS

In our study the total sample size used for both routine and microwave decalcification was 30 premolar teeth and 30 pieces of condyles. The three solutions were dilute nitric acid (5%), formic acid (5%), and EDTA (14%). Each set consisting of the same type of premolars and condyles in each of the three decalcifying solutions were used in both manual method and microwave method.

RESULTS

The results in the present study confirmed the fact that the microwave method using nitric acid was indeed the fastest decalcifying method needing just about 2 days for condyle and 4 days for premolars, compared with routine decalcification. The results also showed that the overall histological picture was good with EDTA and formic acid irrespective of the methods used. In the routine method, nitric acid gave poor cellular detail when compared with microwave method.

CONCLUSION

With our study we conclude that microwave oven decalcification is faster than routine decalcification irrespective of the decalcifying agents used. The tissue preservation and staining efficacy was good in microwave nitric acid decalcification compared to routine nitric acid decalcification. Both formic acid and EDTA show good tissue preservation and staining efficacy irrespective of the method used.

Vibrational assignment of the spectral data, molecular dipole moment, polarizability, first hyperpolarizability, HOMO-LUMO and thermodynamic properties of 5-nitoindan using DFT quantum chemical calculations

The vibrational spectra of 5-nitroindan (NI) was computed using B3LYP methodology with 6-31G(*) and 6-31G(**) basis sets. The FTIR and FT-Raman spectra were recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1) respectively. A similarity was achieved between the observed and calculated frequencies by refinement of the scale factors. The (1)H and (13)CNMR chemical shifts results were also compared with the experimental values. The Mulliken charges, the values of electric dipole moment (μ) of the molecule were computed using DFT calculations. The first order hyperpolarizability (β0) and related properties (β, α0, and Δα) of both are calculated using B3LYP method on the finite-field approach. The electronic properties HOMO and LUMO energies are calculated. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound were calculated.

Density functional theory, comparative vibrational spectroscopic studies, HOMO-LUMO, first hyperpolarizability analyses of 2-fluoro 5-nitrotoluene and 2-bromo 5-nitrotoluene

This work deals with the vibrational spectra of 2-fluoro 5-nitrotoluene and 2-bromo 5-nitrotoluene by quantum chemical calculations. The solid phase FTIR and FT-Raman spectra of the title compounds were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The spectra were interpreted with the aid of normal co-ordinate analysis based on density functional theory (DFT) using standard B3LYP/6-31G(*) basis set for the most optimized geometry. The vibrational frequencies are calculated and scaled values are compared with experimental FTIR and FT-Raman spectra. The scaled theoretical wave numbers showed very good agreement with the experimental ones. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. (13)C and (1)H NMR chemical shifts results are compared with the experimental values.

Comparative morphometric study of AgNORs in variants of ameloblastoma

Aims:

To compare the area and number of AgNORs (silver stained nucleolar organizer regions) by morphometry between follicular and plexiform variants of ameloblastoma in order to analyze their cell proliferation rates.

Materials and Methods:

This retrospective study was carried out on 30 cases each of follicular and plexiform ameloblastoma. The sections were obtained and stained with silver staining technique to identify the nucleolar organizer regions. AgNORs were quantified using two parameters; manual tag for the number of AgNORs and area measurement using the image analyzer software, Image-Pro-Express.

Results:

Morphometric area measurements of AgNOR were significantly higher for Plexiform ameloblastoma (0.831μm²) than follicular ameloblastoma (0.528μm²). Enumeration of the number of AgNORs showed a significantly higher number of AgNOR for follicular ameloblastoma (1.71) than plexiform ameloblastoma (1.43). Among the groups studied, follicular ameloblastoma was more aggressive than plexiform ameloblastoma, as it showed smaller AgNOR area and higher AgNOR number.

Conclusion:

The combination of counting the number and measuring the area of AgNOR dots showed a significant overall difference between AgNOR profiles of follicular and plexiform variants of ameloblastoma.

A new serine protease from the leaves of Thespesia populnea

A serine protease was purified 6.9-fold from the leaves of Thespesia populnea using ammonium sulfate fractionation followed by CM-cellulose and Sephadex G-100 chromatography. The purified enzyme was named populnein and was characterized. It was made up of a single polypeptide, and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) analysis showed that the enzyme had a molecular mass of 14,518 Da. Inhibition of enzyme activity by phenyl methane sulfonyl fluoride indicates that populnein belongs to the class of serine proteases. The enzyme had appreciable pH and temperature stability. The activity of the enzyme was optimal at pH 8.0 and temperature 40°C. The enzyme was thermostable and retained 85% of its activity at 70°C after 1 hr. The enzyme was also resistant to autodigestion. The stabilization of the membrane of red blood cells exhibited by the protease populnein was found to be higher than for diclofenac. More studies are necessary to investigate the biological activity and applications of serine protease of T. populnea.

Antibacterial Activity of Fistulin: A Protease Inhibitor Purified from the Leaves of Cassia fistula

Plant protease inhibitors (PPIs) are one of the important components of a plant's defense machinery. PPIs are active against the insects and microbes which invade the plant. Cassia species possess anti-insecticidal and antimicrobial properties and this study was aimed at investigating the antibacterial efficacy of a PPI present in the leaves of Cassia fistula. A PPI, fistulin, was isolated from the leaves of C. fistula and purified by gel filtration chromatography. The antibacterial activity of the purified fistulin was studied against five bacterial strains, namely, Bacillus subtilis, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli. The PPI was found to be very active against S. aureus, E. coli, B. subtilis, and K. pneumonia, and its efficacy was comparable to the standard drug, streptomycin sulphate.

In Vitro α-Amylase Inhibitory Activity of the Leaves of Thespesia populnea

Postprandial hyperglycemia is a prime characteristic of diabetes mellitus and has been a focus in the therapy for diabetes. One of the therapeutic approaches which involve decreasing hyperglycemia aims at inhibiting the enzyme α-amylase. The leaves of T. populnea were studied for the presence of amylase inhibitors. The fractions obtained by successive fractionation using solvents of varying polarity were studied for the presence of primary and secondary metabolites. The total phenolic content of the different fractions was determined by HPLC and was correlated with their amylase inhibitory potential. Similarly, the protein content of the extracts was also estimated to understand the nature of the inhibitor present. This study shows that the leaves of T. populnea were effective in inhibiting α-amylase, thereby proving to be potential hyperglycemic agents.

Pongamia pinnata seed cake: a promising and inexpensive substrate for production of protease and lipase from Bacillus pumilus SG2 on solid-state fermentation

The production of a protease and a lipase from Bacillus pumilus SG2 on solid-state fermentation using Pongamia pinnata seed cake as substrate was studied. The seed cake was proved to be a promising substrate for the bacterial growth and the enzyme production. The initial pH, incubation time and moisture content were optimized to achieve maximal enzyme production. Maximum protease production was observed at 72 h and that of the lipase at 96 h of incubation. The production of protease (9840 U/g DM) and lipase (1974 U/g DM) were maximum at pH 7.0 and at 60% moisture content. Triton X-100 (1%) was proved to be an effective extractant for the enzymes and their optimal activity was observed at alkaline pH and at 60 C. The molecular mass of the protease and lipase was 24 and 40 kDa, respectively. Both the enzymes were found to be stable detergent additives. The study demonstrated that inexpensive and easily available Pongamia seed cake could be used for production of industrially important enzymes, such as protease and lipase.

Phytochemical screening and in vitro amylase inhibitory effect of the leaves of Breynia retusa

This study was proposed based on the folklore claim and on the scarcity of scientific evidence from the literature for the medicinal uses of Breynia retusa. The aim of the present study was to analyse the phytochemical constituents of the leaves of B. retusa. The fractions obtained by successive fractionation using solvents of varying polarity were studied for the presence of primary and secondary metabolites and the total phenolic content of the different fractions were determined by HPLC. The results of the study support the traditional acclaim of the therapeutic uses of B. retusa. The potential of B. retusa to inhibit alpha-amylase, a prime enzyme involved in carbohydrate metabolism was analysed and it was observed that the ethyl acetate and methanolic extract of the leaves of B. retusa possessed in vitro amylase inhibitory activity.

Activity of Superoxide Dismutase and Catalase in Fenugreek (Trigonella foenum-graecum) in Response to Carbendazim

Fenugreek (Trigonella foenum-graecum) is an annual herb, used as a spice and traditionally as medicine. Fenugreek finds its uses in treating hyperglycemia, hyperlipidemia and disorders of gastro-intestinal and cardiovascular systems. Fenugreek cultivation in India is affected by fungal diseases like root-rot and damping-off and fungicides like carbendazim are used to overcome these infections. Fungicides play both positive and negative role in plants; fungicides protect plants from diseases and also exert oxidative stress simultaneously. This report is on the response of antioxidants, superoxide dismutase and catalase in fenugreek seeds and plants treated to different concentrations of carbendazim.

Barnacle cement: an etchant for stainless steel 316L?

Localized corrosion of stainless steel beneath the barnacle-base is an unsolved issue for the marine industry. In this work, we clearly bring out for the first time the role of the barnacle cement in acting as an etchant, preferentially etching the grain boundaries, and initiating the corrosion process in stainless steel 316L. The investigations include structural characterization of the cement and corroded region, and also chemical characterization of the corrosion products generated beneath the barnacle-base. Structural characterization studies using scanning electron microscopy (SEM) reveals the morphological changes in the cement structure across the interface of the base-plate and the substrate, modification of the steel surface by the cement and the corrosion pattern beneath the barnacle-base. Fourier transform infrared spectroscopy (FTIR) of the corrosion products show that they are composed of mainly oxides of iron thereby implying that the corrosion is aerobic in nature. A model for the etching and corrosion mechanism is proposed based on our observations.

Barnacle cement: An etchant for stainless steel 316L?

Localized corrosion of stainless steel beneath the barnacle-base is an unsolved issue for the marine industry. In this work, we clearly bring out for the first time the role of the barnacle cement in acting as an etchant, preferentially etching the grain boundaries, and initiating the corrosion process in stainless steel 316L. The investigations include structural characterization of the cement and corroded region, and also chemical characterization of the corrosion products generated beneath the barnacle-base. Structural characterization studies using scanning electron microscopy (SEM) reveals the morphological changes in the cement structure across the interface of the base-plate and the substrate, modification of the steel surface by the cement and the corrosion pattern beneath the barnacle-base. Fourier transform infrared spectroscopy (FTIR) of the corrosion products show that they are composed of mainly oxides of iron thereby implying that the corrosion is aerobic in nature. A model for the etching and corrosion mechanism is proposed based on our observations.

Concomitant production of protease and lipase by Bacillus Licheniformis VSG1: Production, purification and characterization

This study was aimed at producing protease and lipase simultaneously on a common medium by Bacillus licheniformis VSG1, which was isolated from a tannery effluent. The effect of media composition with respect to protein source, lipid source and emulsifier on the production of protease and lipase was analysed. Both those enzymes were produced under optimized conditions like pH, temperature and incubation time. The enzyme mixture comprising of both protease and lipase was purified by ammonium sulphate precipitation, dialysis and gel filtration chromatography to obtain 20-fold pure enzymes. The purified enzyme mixture was characterized to determine the optimum pH and temperature of protease and lipase, the response of the enzymes to inhibitors, additives and solvents. The molecular weight of both the enzymes was determined as 40 kDa on SDS-PAGE. The concomitant production of protease and lipase and the purification of both the enzymes in a single mixture have industrial significance, as many industrial processes use both protease and lipase together.

Optimization of process parameters for the extraction of chromium (VI) by emulsion liquid membrane using response surface methodology

The emulsion liquid membrane technique was used for the extraction of hexavalent chromium ions from aqueous solution of waste sodium dichromate recovered from the pharmaceutical industry wastewater. The liquid membrane used was composed of kerosene oil as the solvent, Span-80 as the surfactant and potassium hydroxide as internal reagent. Trioctyl amine and Aliquat-336 were used as carriers. The emulsion stability was carried out at different surfactant concentration, agitation speed and emulsification time. Statistical experimental design was applied for the optimization of process parameters for the extraction of chromium by emulsion liquid membrane. The effects of process parameters namely, agitation speed, membrane to emulsion (M/E) ratio and carrier concentration on the extraction of chromium were optimized using a response surface method. The optimum conditions for the extraction of chromium (VI) using response surface methodology for Trioctyl amine were: agitation speed--201.369rpm, M/E ratio--0.5887% (v/v) and carrier concentration--4.0932% (v/v) and for Aliquat-336: agitation speed--202.097 rpm, M/E ratio--0.5873% (v/v) and carrier concentration --3.9211% (v/v). At the optimized condition the maximum chromium extraction was found to be 89.2% and 96.15% using Trioctyl amine and Aliquat-336, respectively.

Laryngeal schwannomas-case reports with rare presentations

Schwannomas also known as Neurilemmomas are benign encapsulated, slow growing perineural tumours of Neuro-ectodermal origin that arise from the sheet of schwann cells. Two cases are being presented due to their rarity and in both cases the diagnosis was arrived at after the excision of the tumour.

Identification of a high frequency of chromosomal rearrangements in the centromeric regions of prostate cancer patients

The aim of the present investigation was to study the major chromosomal aberrations (CA) like deletion, translocation, inversion and mosaic in prostate cancer patients of Tamilnadu, Southern India. Totally 45 blood samples were collected from various hospitals in Tamilnadu, Southern India. Equal numbers of normal healthy subjects were chosen after signing a consent form. Volunteers provided blood samples (5 ml) to establish leukocyte cultures. Cytogenetic studies were performed by using Giemsa-banding technique and finally the results were ensured by spectral karyotyping (SKY) technique. In the present investigation, major CA like deletion, translocation, inversion and mosaic were identified in experimental subjects. Results showed frequent CA in chromosomes 1, 3, 5, 6, 7, 9, 13, 16, 18 and X. In comparison with experimental subjects, the control subjects exhibited very low levels of major CA (P<0.05). In the present study, the high frequency of centromeric rearrangements indicates a potential role for mitotic irregularities associated with the centromere in prostate cancer tumorigenesis. Identification of chromosome alterations may be helpful in understanding the molecular basis of the disease in better manner.

Structural plasticity and enzyme action: crystal structures of mycobacterium tuberculosis peptidyl-tRNA hydrolase

Peptidyl-tRNA hydrolase cleaves the ester bond between tRNA and the attached peptide in peptidyl-tRNA in order to avoid the toxicity resulting from its accumulation and to free the tRNA available for further rounds in protein synthesis. The structure of the enzyme from Mycobacterium tuberculosis has been determined in three crystal forms. This structure and the structure of the enzyme from Escherichia coli in its crystal differ substantially on account of the binding of the C terminus of the E. coli enzyme to the peptide-binding site of a neighboring molecule in the crystal. A detailed examination of this difference led to an elucidation of the plasticity of the binding site of the enzyme. The peptide-binding site of the enzyme is a cleft between the body of the molecule and a polypeptide stretch involving a loop and a helix. This stretch is in the open conformation when the enzyme is in the free state as in the crystals of M. tuberculosis peptidyl-tRNA hydrolase. Furthermore, there is no physical continuity between the tRNA and the peptide-binding sites. The molecule in the E. coli crystal mimics the peptide-bound enzyme molecule. The peptide stretch referred to earlier now closes on the bound peptide. Concurrently, a channel connecting the tRNA and the peptide-binding site opens primarily through the concerted movement of two residues. Thus, the crystal structure of M. tuberculosis peptidyl-tRNA hydrolase when compared with the crystal structure of the E. coli enzyme, leads to a model of structural changes associated with enzyme action on the basis of the plasticity of the molecule.

Cloning, expression, purification, crystallization and preliminary X-ray analysis of peptidyl-tRNA hydrolase from Mycobacterium tuberculosis

Peptidyl-tRNA hydrolase catalyses the cleavage of the ester link between the peptide and the tRNA in peptidyl-tRNAs that, for various reasons, have dropped off the translating ribosomes. This enzyme from Mycobacterium tuberculosis has been crystallized in three related but distinct forms: P2(1)2(1)2(1), unit-cell parameters a = 36.30, b = 61.85, c = 73.97 A, P2(1), a = 35.83, b = 73.79, c = 59.79 A, beta = 92.3 degrees , and P2(1)2(1)2(1), a = 35.84, b = 57.06, c = 72.59 A. X-ray data have been collected from all three forms.