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1.
Entropy (Basel) ; 24(11)2022 Nov 19.
Article in English | MEDLINE | ID: mdl-36421550

ABSTRACT

This paper establishes a close relationship among the four information theoretic problems, namely Campbell source coding, Arikan guessing, Huleihel et al. memoryless guessing and Bunte and Lapidoth tasks' partitioning problems in the IID-lossless case. We first show that the aforementioned problems are mathematically related via a general moment minimization problem whose optimum solution is given in terms of Renyi entropy. We then propose a general framework for the mismatched version of these problems and establish all the asymptotic results using this framework. The unified framework further enables us to study a variant of Bunte-Lapidoth's tasks partitioning problem which is practically more appealing. In addition, this variant turns out to be a generalization of Arikan's guessing problem. Finally, with the help of this general framework, we establish an equivalence among all these problems, in the sense that, knowing an asymptotically optimal solution in one problem helps us find the same in all other problems.

2.
Biomater Adv ; 134: 112592, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35527134

ABSTRACT

The present study demonstrates lignin (L), fragments of lignin (FL), and oxidized fragmented lignin (OFL) as templates for the synthesis of zinc oxide nanoparticles (ZnO NPs) viz., lignin-ZnO (L-ZnO), hierarchical FL-ZnO, and OFL-ZnO NPs. The X-ray diffraction patterns confirmed the formation of phase pure ZnO NPs with a hexagonal wurtzite structure. Electron microscopy confirmed the hierarchical structures with one-dimensional arrays of ZnO NPs with an average particle diameter of 40 nm. The as-synthesized L-ZnO, FL-ZnO, and OFL-ZnO NPs were tested in-vitro for growth and virulence inhibition (morphogenesis and biofilm) in Candida albicans. L-ZnO, FL-ZnO, and OFL-ZnO NPs all inhibited growth and virulence. Growth and virulence inhibitions were highest (more than 90%, respectively at 125, 31.2, and 62.5 µg/mL) in presence of FL-ZnO NPs, indicating that the hierarchical FL-ZnO NPs were potent growth and virulence inhibiting agent than non-hierarchical ZnO NPs. Furthermore, the real-time polymerase chain (RT-PCR) was used to study the virulence inhibition molecular mechanisms of L-ZnO, FL-ZnO, and OFL-ZnO NPs. RT-PCR results showed that the downregulation of phr1, phr2, efg1, hwp1, ras1, als3 and als4, and the upregulation of bcy1, nrg1, and tup1 genes inhibited the virulence in C. albicans. Lastly, we also performed in-vitro test cell cytotoxicity on the cell line, mouse embryo 3T3L1, and in-vivo toxicity on Rats, which showed that FL-ZnO NPs were biocompatible and nontoxic.


Subject(s)
Biofilms , Candida albicans , Nanoparticles , Zinc Oxide , Animals , Biofilms/drug effects , Candida albicans/metabolism , Lignin , Mice , Nanoparticles/chemistry , Rats , Zinc Oxide/pharmacology
3.
Bioorg Chem ; 120: 105597, 2022 03.
Article in English | MEDLINE | ID: mdl-35033817

ABSTRACT

The significance of B-RAF in the promotion of cell proliferation and motility was explored by the researchers in the past. However, in 2002, several researchers found that mutation in B-RAF leads to cancer. Extensive research on B-RAF mutations suggested B-RAF V600E mutation as a critical predictive, prognostic and diagnostic biomarker in numerous cancers such as melanoma, thyroid, and colorectal cancers. Based on the significance of B-RAF kinase and associated mutation, the present review will give a brief overview about structure and functions of B-RAF enzyme, its role in different types of cancer, available drugs in the market for B-RAF inhibition, chemical classification and SAR studies of reported investigational B-RAF inhibitors in patented and non-patented literature during last decade. The SAR provided for all the reported inhibitors will help researchers to gain knowledge about the possible structural features required for selective B-RAF inhibition. This insightful analysis of B-RAF will certainly help researchers to develop novel anticancer agents in the future.


Subject(s)
Antineoplastic Agents , Melanoma , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Humans , Mutation , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins B-raf
4.
J Sep Sci ; 44(15): 2982-2995, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34085766

ABSTRACT

Endocrine disrupting chemicals are chemicals that interfere with any aspect of the endocrine system. Several natural and synthetic chemicals, including pesticides, have been identified as endocrine disruptors, which potentially inhibit the reproductive activity of the hormonal system. The pervasive occurrence with trace level concentrations and extensive variety are the reported characteristics of these chemicals. In this study, a dispersive liquid-liquid microextraction method coupled with gas chromatography and mass spectrometry for the determination of eight potential endocrine disruptor pesticides (Lindane, Diazinon, Fenitrothion, Malathion, Aldrin, α-Endosulfan, ß-Endosulfan, Methoxychlor) in bovine milk samples was developed. Several parameters that can influence the extraction efficiency were studied. Under optimized conditions, the calibration curves of all eight analytes presented coefficient of determination higher than 0.998 (range level of 2.0-1000 ng/mL). The limits of detection and quantification ranged from 0.90 to 5.00 ng/mL and 2.50 to 15.0 ng/mL, respectively.


Subject(s)
Endocrine Disruptors/analysis , Gas Chromatography-Mass Spectrometry/methods , Liquid Phase Microextraction/methods , Milk/chemistry , Pesticides/analysis , Animals , Cattle , Limit of Detection , Solvents/chemistry
5.
RSC Adv ; 9(5): 2484-2492, 2019 Jan 18.
Article in English | MEDLINE | ID: mdl-35520531

ABSTRACT

In the present study, we demonstrated the use of fragmented lignin in the synthesis of a hierarchical-type structure of ZnO nanorods. Lignin was isolated from bagasse by the microwave assisted method and its fragmentation was achieved in alkaline conditions along with hydrogen peroxide. Lignin and fragmented lignin were purified by crystallisation followed by column chromatography and characterized by UV-visible spectroscopy, Frontier infra-red spectroscopy (FTIR), 1H-NMR and high resolution mass spectroscopy (HRMS). Fragmented lignin was utilized as a template for the synthesis of ZnO nanorods, which were characterized by powder XRD, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-DRS for the determination of crystal structure, particle morphology and band gap. XRD of the ZnO samples revealed a hexagonal wurtzite structure. The morphology of ZnO without fragmented lignin showed agglomerated nanoparticles and with fragmented lignin, a self-assembled hierarchical nanostructure due to nanorods of 30 nm diameter and 200-500 nm length was observed. The fragmented lignin showed a pronounced effect on the particle size and morphology of ZnO nanoparticles. We measured the response of the hierarchical ZnO nanostructure (50 ppm) for sensing NH3 in terms of change in voltage across known resistance. We observed the response and recovery upon introduction of the analyte ammonia gas at 175 °C.

6.
Am J Med Sci ; 354(5): 467-470, 2017 11.
Article in English | MEDLINE | ID: mdl-29173357

ABSTRACT

BACKGROUND: The objective of this study was to assess the albumin cobalt binding (ACB) test in a cohort of type 2 diabetes patients. The ACB test is a simple, inexpensive, sensitive and robust test that could have important clinical application in detecting complications of type 2 diabetes mellitus. MATERIALS AND METHODS: We tested patients with type 2 diabetes without any clinically detectable complications or without any other comorbid conditions for serum ACB levels along with an equal number of age- and sex-matched healthy control subjects. ACB levels were compared after the patients with diabetes were investigated for various complications using standard statistical tests of significance. RESULTS: A total of 100 patients with type 2 diabetes were studied with age- and sex-matched healthy control subjects. Of the 100 patients, 78 had different complications on detailed laboratory testing. The patients with complications had significantly higher ACB test results when compared to the patients with diabetes without complications and to that of the control subjects (0.62 ± 0.04, 0.42 ± 0.07, 0.30 ± 0.05absorbance units (ABSU)/mL, respectively. P < 0.001). All values in diabetics were significantly higher than that of controls. CONCLUSIONS: The serum ACB test is a sensitive indicator of complications developed in type 2 diabetes mellitus. Patients may be followed up with ACB results to detect early complications in this disease.


Subject(s)
Diabetes Complications/diagnosis , Diabetes Mellitus, Type 2/complications , Adult , Aged , Biomarkers/metabolism , Cobalt/metabolism , Female , Humans , Male , Middle Aged , Serum Albumin, Human/metabolism
7.
J Parasit Dis ; 41(2): 557-561, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28615878

ABSTRACT

A total of 715 faecal sampleswere collected fromdairy animals ofeight tehsils ofBikaner district, Rajasthan during March 2015 to January 2016. An overall prevalence rate of 54.12 % was recorded for gastrointestinal helminthoses with highly statistical difference among dairy animals (p < 0.01). Quantitative analysis revealed mild to high severity of strongyle and Strongyloides sp. infections in cattle population, respectively whereas, mild severities of same infections were reported from the buffalo population of the region. Seasonal analysis revealed a non-significant difference with highest prevalence in rainy season (59.18 %). The tehsil wise analysis revealed a significant difference (p < 0.05) among tehsils with highest prevalence in Chhatargarh (69.70 %). Multivariate binary regression model revealed rainy season as the most favorable season and Chattargarh as the tehsil with maximum risk for GI helminth infections.On coproculture of positive samples, the nematode infections in decreasing order of prevalence were Haemonchus sp. (36.33 %); Oesophagostomum sp. (26.33 %); Strongyloides sp. (13.67 %); Trichostrongylus sp. (11.67 %); Bunostomum sp. (7.33 %) and Cooperia sp. (4.67 %). Thebaseline data on the prevalence of various GI Helminths of dairy animals generated in the current study would be of immense help in formulating control strategies against infections inBikaner district.

9.
Funct Integr Genomics ; 16(5): 557-66, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27492417

ABSTRACT

Genomic studies provide deeper insights into secondary metabolites produced by diverse bacterial communities, residing in various environmental niches. This study aims to understand the potential of a biosurfactant producing Bacillus sp. AM13, isolated from soil. An integrated approach of genomic and chemical analysis was employed to characterize the antibacterial lipopeptide produced by the strain AM13. Genome analysis revealed that strain AM13 harbors a nonribosomal peptide synthetase (NRPS) cluster; highly similar with known biosynthetic gene clusters from surfactin family: lichenysin (85 %) and surfactin (78 %). These findings were substantiated with supplementary experiments of oil displacement assay and surface tension measurements, confirming the biosurfactant production. Further investigation using LCMS approach exhibited similarity of the biomolecule with biosurfactants of the surfactin family. Our consolidated effort of functional genomics provided chemical as well as genetic leads for understanding the biochemical characteristics of the bioactive compound.


Subject(s)
Bacillus/genetics , Bacterial Proteins/metabolism , Peptide Synthases/genetics , Surface-Active Agents/metabolism , Bacillus/metabolism , Bacterial Proteins/biosynthesis , Bacterial Proteins/genetics , Genome, Bacterial , Genomics , Peptide Synthases/isolation & purification , Secondary Metabolism/genetics
10.
Public Health Nutr ; 19(5): 767-76, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26250989

ABSTRACT

OBJECTIVE: To assess trends in nutrient intakes and nutritional status of rural adult women (≥18-60 years) and the association of sociodemographic characteristics with overweight/obesity. DESIGN: Community-based cross-sectional studies carried out during 1975-79 to 2011-12 by the National Nutrition Monitoring Bureau (NNMB) were used. Anthropometric measurements such as height, weight and waist circumference, carried out during the surveys, were used. Association and logistic regression analyses between sociodemographic characteristics and overweight/obesity and abdominal obesity were conducted using a complex samples procedure. SETTING: Ten NNMB states of India. SUBJECTS: Non-pregnant and non-lactating rural women aged ≥18-60 years covered during the above periods from ten states in India. RESULTS: The prevalence of chronic energy deficiency has declined from 52 % during 1975-79 to 34 % during 2011-12, while that of overweight/obesity has increased from 7 % to 24 % during the same period. Median intakes of most of the nutrients have increased over the same period, although they were below recommended levels. The chance of overweight/obesity and abdominal obesity was significantly (P<0·01) higher among women aged 40-60 years, those belonging to Christian religion and other backward communities, women living in pucca houses, literate women, women engaged in service and business, and those having higher per capita income. CONCLUSIONS: Prevalence of chronic energy deficiency has declined significantly; however, overweight/obesity has increased during the same period. This increase in overweight/obesity may be attributed to increased consumption of fatty foods, sedentary lifestyle and improved socio-economic status. There is a need to educate the community about regular physical exercise, low intakes of fats and oils, and a balanced diet.


Subject(s)
Diet , Energy Intake , Nutritional Status , Obesity/epidemiology , Overweight/epidemiology , Rural Population , Adolescent , Adult , Body Height , Body Mass Index , Body Weight , Cross-Sectional Studies , Dietary Fats/administration & dosage , Exercise , Female , Humans , India/epidemiology , Logistic Models , Middle Aged , Nutrition Surveys , Prevalence , Socioeconomic Factors , Waist Circumference , Young Adult
11.
Int J Pharm Investig ; 5(4): 205-13, 2015.
Article in English | MEDLINE | ID: mdl-26682191

ABSTRACT

BACKGROUND: The aim of the present study was to formulate and optimize the self-emulsifying drug delivery systems (SEDDS) of nevirapine (NVP) by use of 2(2) factorial designs to enhance the oral absorption of NVP by improving its solubility, dissolution rate, and diffusion profile. SEDDS are the isotropic mixtures of oil, surfactant, co-surfactant and drug that form oil in water microemulsion when introduced into the aqueous phase under gentle agitation. MATERIALS AND METHODS: Solubility of NVP in different oils, surfactants, and co-surfactants was determined for the screening of excipients. Pseudo-ternary phase diagrams were constructed by the aqueous titration method, and formulations were developed based on the optimum excipient combinations with the help of data obtained through the maximum micro emulsion region containing combinations of oil, surfactant, and co-surfactant. The formulations of SEDDS were optimized by 2(2) factorial designs. RESULTS: The optimum formulation of SEDDS contains 32.5% oleic acid, 44.16% tween 20, and 11.9% polyethylene glycol 600 as oil, surfactant, and co-surfactant respectively. The SEDDS was evaluated for the following drug content, self-emulsification time, rheological properties, zeta potential, in vitro diffusion studies, thermodynamic stability studies, and in vitro dissolution studies. An increase in dissolution was achieved by SEDDS compared to pure form of NVP. CONCLUSION: Overall, this study suggests that the dissolution and oral bioavailability of NVP could be improved by SEDDS technology.

12.
Pharmacognosy Res ; 2(2): 107-12, 2010 Mar.
Article in English | MEDLINE | ID: mdl-21808550

ABSTRACT

Methanolic extracts of 6 wild edible mushrooms isolated from the Western Ghats of Karnataka were used in this study. Among the isolates (Lycoperdon perlatum, Cantharellus cibarius, Clavaria vermiculris, Ramaria formosa, Marasmius oreades, Pleurotus pulmonarius), only 4 showed satisfactory results. Quantitative analysis of bioactive components revealed that total phenols are the major bioactive component found in extracts of isolates expressed as mg of GAE per gram of fruit body, which ranged from 3.20 ± 0.05 mg/mL to 6.25 ± 0.08 mg/mL. Average concentration of flavonoid ranged from 0.40 ± 0.052 mg/mL to 2.54 ± 0.08 mg/mL; followed by very small concentration of ascorbic acid (range, 0.06 ± 0.01 mg/mL to 0.16 ± 0.01 mg/mL) in all the isolates. All the isolates showed high phenol and flavonoid content, but ascorbic acid content was found in traces. Antioxidant efficiency by inhibitory concentration on 1,1-Diphenly-2-picrylhydrazyl (DPPH) was found significant when compared to standard antioxidant like Buthylated hydroxyanisol (BHA). The concentration (IC(50)) ranged from 0.94 ± 0.27 mg/mL to 7.57 ± 0.21 mg/mL. Determination of antimicrobial activity profile of all the isolates tested against a panel of standard pathogenic bacteria and fungi indicated that the concentrations of bioactive components directly influence the antimicrobial capability of the isolates. Agar diffusion assay showed considerable activity against all bacteria. Minimum inhibitory concentration values of the extracts of 4 isolates showed that they are also active even in least concentrations. These results are discussed in relation to therapeutic value of the studied mushrooms.

13.
BMC Complement Altern Med ; 4: 11, 2004 Aug 13.
Article in English | MEDLINE | ID: mdl-15310392

ABSTRACT

BACKGROUND: The major damaging factor during and after the ischemic/hypoxic insult is the generation of free radicals, which leads to apoptosis, necrosis and ultimately cell death. Rubia cordifolia (RC), Fagonia cretica linn (FC) and Tinospora cordifolia (TC) have been reported to contain a wide variety of antioxidants and have been in use in the eastern system of medicine for various disorders. However, their mechanism of action was largely unknown. We therefore selected these herbs for the present study to test their neuroprotective ability and the associated mechanism in rat hippocampal slices subjected to oxygen-glucose deprivation (OGD). METHODS: Hippocampal Slices were subjected to OGD (oxygen glucose deprivation) and divided into 3 groups: control, OGD and OGD + drug treated. Cytosolic Cu-Zn superoxide dismutase (Cu-Zn SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), nitric oxide (NO) was measured as nitrite (NO2) in the supernatant and protein assays were performed in the respective groups at various time intervals. EPR was used to establish the antioxidant effect of RC, FC and TC with respect to superoxide anion (O2.-), hydroxyl radicals (. OH), nitric oxide (NO) radical and peroxynitrite anion (ONOO) generated from pyrogallol, menadione, DETA-NO and Sin-1 respectively. RT-PCR was performed for the three groups for GCLC, iNOS, Cu-Zn SOD and GAPDH gene expression. RESULTS: All the three herbs were effective in elevating the GSH levels, expression of the gamma-glutamylcysteine ligase and Cu-Zn SOD genes. The herbs also exhibited strong free radical scavenging properties against reactive oxygen and nitrogen species as studied by electron paramagnetic resonance spectroscopy. In addition all the three herbs significantly diminished the expression of iNOS gene after 48 hours which plays a major role in neuronal injury during hypoxia/ischemia. CONCLUSIONS: RC, FC and TC therefore attenuate oxidative stress mediated cell injury during OGD and exert the above effects at both the cytosolic as well as at gene expression level and may be an effective therapeutic tool against ischemic brain damage.


Subject(s)
Brain Ischemia/therapy , Hippocampus/metabolism , Neuroprotective Agents/pharmacology , Plant Preparations/pharmacology , Rubia , Tinospora , Zygophyllaceae , Animals , Antioxidants/metabolism , Brain Ischemia/metabolism , Gene Expression , Glucose/metabolism , Glutathione/metabolism , In Vitro Techniques , Male , Nitric Oxide Synthase/metabolism , Nitrogen/metabolism , Oxygen/metabolism , Phytotherapy , Plant Proteins/metabolism , Rats , Rats, Wistar , Reactive Oxygen Species/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Superoxide Dismutase/metabolism , Up-Regulation
15.
Chem Commun (Camb) ; (18): 2014-5, 2002 Sep 21.
Article in English | MEDLINE | ID: mdl-12357756

ABSTRACT

Highly dispersed zirconium oxide species on silica exhibit fine structure in phosphorescence emission spectra showing the vibration energy of the photoactive Zr-O-Si linkage to be 955 cm-1, and the species promotes the photoinduced non-oxidative methane coupling at room temperature.

16.
J Parasitol ; 78(1): 77-81, 1992 Feb.
Article in English | MEDLINE | ID: mdl-1738073

ABSTRACT

Four antigenic preparations, viz. salivary gland antigen (SG Ag), whole tick extract antigen (WTE Ag) and 30,000-g supernatant fraction, and pellet of WTE Ag (TES Ag and TEP Ag, respectively), were made from partially fed adult female Hyalomma anatolicum anatolicum. Four groups of 5 rabbits each were immunized with the antigens, and a fifth group was kept as control. Following challenge with adult H. a. anatolicum, a significant decrease in engorgement weight and egg mass weight and an increase in engorgement period and preoviposition period were observed in WTE Ag-immunized rabbits. Similar results were observed with TES Ag and SG Ag, except that change in the engorgement period was insignificant. However, none of the tick parameter measurements showed significant changes with TEP Ag. None of the antigens produced significant changes in the percentage of engorgement or oviposition period of the challenged ticks. Thus, WTE Ag was the most effective in altering tick performances.


Subject(s)
Antigens/immunology , Immunization , Tick Infestations/immunology , Ticks/immunology , Animals , Female , Male , Oviposition , Rabbits , Reproduction , Tick Infestations/parasitology , Tick Infestations/prevention & control , Ticks/physiology
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