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1.
Mar Pollut Bull ; 200: 116126, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38330813

ABSTRACT

The present study assessed the trophic status of a medium-sized microtidal estuary, Rushikulya, India using a combination of mutimetric trophic indices (TRIX, TRBIX) and a machine learning approach (Random Forest). A total of 108 samples were considered to build a predictive model for chlorophyll a (Chl a) and 17 response water variables by observing two annual periods (2021-2023) at six sampling sites. Mean values of TRIX (5.04 ± 0.72) and TRBIX (0.17 ± 0.08) reflected that the estuary has a moderate degree of eutrophication with 'good' water quality and 'biomass saturated'. However, the threshold of TRIX represents a transition state from 'moderate' to 'high' eutrophic. Random Forest model reflected that no apparent association between Chl a and water turbidity above 30 NTU and eutrophication in the estuary fluctuated mainly due to PO43--P along with electrical conductivity. Linear statistical correlations showed high correlation between Chl a and conductivity and a negative correlation between Chl a and dissolved oxygen, unlike PO43--P.


Subject(s)
Environmental Monitoring , Estuaries , Chlorophyll A , Random Forest , Water Quality , Eutrophication , Chlorophyll/analysis
2.
Front Microbiol ; 14: 1173986, 2023.
Article in English | MEDLINE | ID: mdl-37152724

ABSTRACT

Introduction: The perennial grass-legume cropping system benefits soil because of its high biomass turnover, cover cropping nature, and different foraging behaviors. We investigated the response of soil organic carbon (SOC) pools and their stock to organic and inorganic nutrient management in the Guinea grass and legume (cowpea-Egyptian clover) cropping system. Methods: Depth-wise soil samples were collected after harvesting the Egyptian clover. Based on the ease of oxidation with chromic acid, different pools of SOC oxidizable using the Walkley-Black C method, very labile, labile, less labile, non-labile; and dissolved organic C (DOC), microbial biomass C (MBC), and total organic C (TOC) in soils were analyzed for computing several indices of SOC. Result and discussion: After 10 years of crop cycles, FYM and NPKF nutrient management recorded greater DOC, MBC, SOC stocks, and C sequestration than the NPK. Stocks of all SOC pools and carbon management index (CMI) decreased with soil depth. A significant improvement in CMI, stratification ratio, sensitivity indices, and sustainable yield index was observed under FYM and NPKF. This grass-legume intercropping system maintained a positive carbon balance sequestered at about 0.8Mg C ha-1 after 10 years without any external input. Approximately 44-51% of the applied carbon through manure was stabilized with SOC under this cropping system. The DOC, MBC, and SOC in passive pools were identified for predicting dry fodder yield. This study concludes that the application of organics in the perennial grass-legume inter cropping system can maintain long-term sustainability, enhance the C sequestration, and offset the carbon footprint of the farm enterprises.

3.
Environ Sci Pollut Res Int ; 30(29): 73185-73201, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37184785

ABSTRACT

Anthropogenic activities impacted the ecological health of rivers by altering the physical habitat and water flow as well as by pollution. Monitoring of biotic groups for gauging the river health is a prerequisite for assessing the extent of degradation and formulating management guidelines for river restoration. An assessment using fish-based index of biotic integrity (IBI) was carried out in the Central Indian river, Tapti, for probing its health status. For the multimetric index, twelve metrics were adopted under five categories: taxonomic richness, habitat composition, tolerance indicators, species resilience, and trophic composition. Among the studied sites, Betul in the upper stretch was selected as the reference site for River Tapti, which almost meets the upper expectation of the metrics explored. Continuous scoring method was applied to evaluate the biotic integrity in the selected sites of the river. The IBI score based on the pooled fish abundance data in River Tapti ranged from 33 to 60. Assessment of the ecological health revealed that three-fourth of the river stretch was moderately impaired (25-50% of impairment) and the most deteriorated site was Kamrej with 45% of impairment which might be due to its location in the urban area with high influx of domestic sewage and industrial effluents. The IBI scores were plotted and compared with an independent estimate of water quality. The CCA with environmental and IBI variables revealed higher correlation with each other and the functional groups such as carnivores, herbivores, and fishes with high population doubling time (PDT) were found in close association with nitrate-N, total alkalinity, and specific conductivity. The study urges the need for the adoption of proper management and mitigation measures to restore the health and wealth of aquatic ecosystem.


Subject(s)
Ecosystem , Environmental Monitoring , Animals , Environmental Monitoring/methods , Rivers , Fishes , Health Status , India
4.
J Parasit Dis ; 46(1): 18-23, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35299923

ABSTRACT

The present paper deals with the infestation of freshwater fishes Labeo boggut, Oreochromis niloticus, Systomus sarana, and Xenentodon cancila by the parasitic isopods Alitropus typus and Tachaea spongillicola in Tapti, a westward freshwater flowing river of India. The isopods Alitropus typus H. Milne Edwards, 1840 and Tachaea spongillicola Stebbing, 1907 were identified with the taxonomic keys of Milne Edwards (1840) and Stebbing (1907), respectively. It is the first record of the infestation of parasitic isopods Alitropus typus, and Tachaea spongillicola in the freshwater fishes of river Tapti with new hosts' species Labeo boggut, Oreochromis niloticus, and Systomus sarana.

5.
Environ Sci Pollut Res Int ; 29(30): 45981-46002, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35157203

ABSTRACT

The present study illustrates a holistic account of zooplankton community dynamics in relation to physicochemical variables in the tidal creeks of Indian Sundarbans estuarine system. Eleven water variables and zooplankton samples were collected in a monthly basis from the six sampling locations between July 2016 and June 2018. Out of the 11 water parameters, seven parameters (temperature, salinity, dissolved oxygen, turbidity, PO4 - P, NO3 - N, and NO2 - N) varied significantly (p ≤ 0.05) among seasons. A total of 63 zooplankton taxa were recorded with the predominance of Copepoda. Permutational multivariate analysis of variance (PERMANOVA) depicted the significant variations of zooplankton population both spatially (F = 2.313; p = 0.001) and temporally (F = 6.107; p = 0.001). Out of the 41 species of Copepoda recorded, 14 species (Paracalanus parvus, Parvocalanus dubia, Bestiolina similis, Acrocalanus gibber, A. gracilis, Acartia erythraea, A. spinicauda, Pseudodiaptomus serricaudatus, P. annandalei, P. aurivilli, Oithona brevicornis, O. similis, Longipedia weberi and Microsetella norvegica) were indicated as "characterizing species" in the creek environment, which highlighted the euryhaline nature as well as broad range of thermal tolerance of these species. Acrocalanus longicornis, Eucalanus crassus, Candacia bradyi, and Acartia sewelli were specifically found in pre-monsoon; Euterpina acutiformis, Clytemnestrata rostrata, Acartia plumosa, and Canthocalanus pauper were specific to post-monsoon season, whereas Mesocyclops leuckarti, Temora turbinata, and Temora discaudata were found only during monsoon. Thus, it explains the limited period of existence, highlighting the temporal shift in species abundance in the creeks. Overall, the calculated mean value of α-diversity (d' = 4.07; H' = 2.31) indicated a "good" zooplankton diversity in the creeks. The biota-environmental relationship following canonical correspondence analysis revealed that variables, viz., water temperature, turbidity, and NO3 - N, were the explanatory variables during monsoon; pH and DO in post-monsoon; PO4 - P, SiO4 - Si, and salinity in pre-monsoon that explained the variations of zooplankton community compositions in the creeks. The variables (PO4 - P, NO3 - N, and SiO4 - Si) that are correlated to the zooplankton community implied their indirect effect on the distribution of zooplankton by supporting the phytoplankton succession and production in the mangrove-dominated creeks.


Subject(s)
Copepoda , Zooplankton , Animals , Environmental Monitoring , India , Phytoplankton , Seasons , Water
6.
ACS Omega ; 6(43): 28699-28709, 2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34746564

ABSTRACT

Interpenetrating polymer network (IPN)-based bead formulations were exploited by cross-linking different hydrophilic polymers in different combinations and at different ratios. Polyvinyl alcohol, xanthan gum, guar gum, gellan gum, and sodium alginate (Na-alginate) were used in this work as hydrophilic polymers to enhance the solubility of diclofenac sodium and also to target the delivery at preferred locations. IPN beads based on polysaccharides were prepared by the ionic gelation method. Differential scanning calorimetry, powder X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy data showed that the IPN microbeads solubilized and encapsulated the drug within the network. We found over 83% encapsulation efficiency of the drug delivery system for the drug, and this efficiency increased with the concentration of the polymer. Ex vivo experiments using the goat intestine revealed that the IPN microbeads were able to adhere to the intestinal epithelium, a mucoadhesive behavior that could be beneficial to the drug pharmacokinetics, while in vitro experiments in phosphate buffer showed that the IPN enabled significant drug release. We believe that these IPN microbeads are an excellent drug delivery system to solubilize drug molecules and ensure adhesion to the intestinal wall, thereby localizing the drug release to enhance bioavailability of poorly soluble drugs.

7.
Molecules ; 26(9)2021 Apr 25.
Article in English | MEDLINE | ID: mdl-33923006

ABSTRACT

Phosphine-borane complexes are novel chemical entities with preclinical efficacy in neuronal and ophthalmic disease models. In vitro and in vivo studies showed that the metabolites of these compounds are capable of cleaving disulfide bonds implicated in the downstream effects of axonal injury. A difficulty in using standard in silico methods for studying these drugs is that most computational tools are not designed for borane-containing compounds. Using in silico and machine learning methodologies, the absorption-distribution properties of these unique compounds were assessed. Features examined with in silico methods included cellular permeability, octanol-water partition coefficient, blood-brain barrier permeability, oral absorption and serum protein binding. The resultant neural networks demonstrated an appropriate level of accuracy and were comparable to existing in silico methodologies. Specifically, they were able to reliably predict pharmacokinetic features of known boron-containing compounds. These methods predicted that phosphine-borane compounds and their metabolites meet the necessary pharmacokinetic features for orally active drug candidates. This study showed that the combination of standard in silico predictive and machine learning models with neural networks is effective in predicting pharmacokinetic features of novel boron-containing compounds as neuroprotective drugs.


Subject(s)
Boranes/chemistry , Machine Learning , Neuroprotective Agents/chemistry , Phosphines/chemistry , Blood-Brain Barrier/drug effects , Boranes/pharmacology , Computer Simulation , Humans , Neuroprotection/drug effects , Neuroprotective Agents/pharmacology , Phosphines/pharmacology , Protein Binding/drug effects
8.
Pharm Nanotechnol ; 9(1): 36-50, 2021.
Article in English | MEDLINE | ID: mdl-33319695

ABSTRACT

Poly (lactic-co-glycolic acid) (PLGA) is a versatile synthetic polymer comprehensively used in the pharmaceutical sector because of its biocompatibility and biodegradability. These benefits lead to its application in the area of nanoparticles (NPs) for drug delivery for over thirty years. This article offers a general study of the different poly (lactic-co-glycolic acid) nanoparticles (PNPs), preparation methods such as emulsification-solvent evaporation, coacervation, emulsification solvent diffusion, dialysis, emulsification reverse salting out, spray drying nanoprecipitation, and supercritical fluid technology, from the methodological point of view. The physicochemical behavior of PNPs, including morphology, drug loading, particle size and its distribution, surface charge, drug release, stability as well as cytotoxicity study and cellular uptake, are briefly discussed. This survey additionally coordinates to bring a layout of the significant uses of PNPs in different drug delivery system over the three decades. At last, surface modifications of PNPs and PLGA nanocomplexes (NCs) are additionally examined.


Subject(s)
Glycols , Nanoparticles , Drug Carriers , Drug Delivery Systems , Glycolates , Polylactic Acid-Polyglycolic Acid Copolymer
9.
Int J Biol Macromol ; 130: 645-654, 2019 Jun 01.
Article in English | MEDLINE | ID: mdl-30797807

ABSTRACT

This study aimed to develop and characterize the calcium alginate films loaded with diclofenac sodium and other hydrophilic polymers with different degrees of cross-linking obtained by external gelation process. To the formed films different physicochemical evaluation were performed which showed an initial character of the films. The films produced by this external gelation process were found thicker (0.031-0.038 mm) and stronger (51.9-52.9 MPa) but less elastic (2.3%) than those non-cross-linked films (0.029 mm; 39.7 MPa; 4.4%). The lower water vapor permeability (WVP) values of the films were obtained where maximum level of crosslinking occurs. Composite films can be cross-linked in presence of external crosslinking agent to improve the quality of the produced matrices for various uses. The characterization of the film was performed using Differential Scanning Calorimetry (DSC) and Fourier-Transform Infrared Spectroscopy (FT-IR) analysis. The Scanning Electron Microscopy (SEM) study showed the morphology of treated composite films. The kinetic release studies showed a sustained release of the drug from the formulated films as it can be prolonged in composite film. The prepared biodegradable Ca-Alginate bio-composite film may be of clinical importance for its therapeutic benefit.


Subject(s)
Alginates/chemistry , Biocompatible Materials/chemistry , Biopolymers/chemistry , Drug Carriers/chemistry , Chemical Phenomena , Drug Delivery Systems , Hydrogen-Ion Concentration , Materials Testing , Mechanical Phenomena , Spectrum Analysis
10.
Curr Drug Deliv ; 15(6): 795-817, 2018.
Article in English | MEDLINE | ID: mdl-29336262

ABSTRACT

BACKGROUND: In the study of lipid vesicular carriers in permeation enhancement of drug molecules across skin after the success story of liposomes, ethosomes are a recent addition. There are a number of published reviews but still, there is a lack of reviews representing various aspects in a systematic way with a detailed description of current research works. This review serves to fill this deficiency along with special emphasize on its preparation methods and applications. METHODS: Information was collected from previously published literatures which were represented after analysis in terms of various aspects such as principles, composition, preparation, mechanism of penetration, modified forms, characterization, marketed preparations and its applications. RESULT: This review is represented in an informative and easily understandable way. Basic principles and background were covered in the introduction section. Composition section contains the basic components of formulations along with the impact of various parameters on the characterization of the ethosome. A detailed discussion of all the methods along with their own utility is elaborately provided. Various aspects of characterization studies of ethosomes are also discussed. Therapeutic and cosmetic applications of ethosomes are also outlined here. CONCLUSION: In spite of having a excellent permeation-enhancing and targeted drug release profile, ethosome suffers from limited commercialization. Various challenges regarding their commercialization and product development are also discussed in this review with an objective of acting as a directional route for the researchers.


Subject(s)
Lipids/chemistry , Animals , Drug Carriers/chemistry , Humans , Liposomes/chemistry
11.
Endocrinology ; 159(3): 1303-1327, 2018 03 01.
Article in English | MEDLINE | ID: mdl-29300860

ABSTRACT

Retinoid X receptor (RXR) occupies a central position within the nuclear receptor superfamily, serving as an obligatory partner to numerous other nuclear receptors, including vitamin D receptor (VDR). In the current study, we examined whether phosphorylation of RXRα at serine 260 affects VDR/RXR and VDR interacting protein (DRIP) 205 coactivator recruitment, interactions, and binding of the VDR/human RXRα (hRXRα)/DRIP205 complex to chromatin. Serine 260 is a critical amino acid on the hRXRα that is located in close spatial proximity to regions of coactivator and corepressor interactions. Using fluorescence resonance energy transfer and immunofluorescence studies, we showed that the physical interaction between hRXRα and DRIP205 coactivator was impaired in human keratinocytes with the ras oncogene (HPK1Aras) or transfected with the wild-type hRXRα. Furthermore, the nuclear colocalization of VDR/DRIP205, hRXRα/DRIP205, and VDR/hRXRα/DRIP205 complex binding to chromatin is impaired in the HPK1Aras cells when compared with the normal human keratinocytes (HPK1A cells). However, transfection with the nonphosphorylatable hRXRα (S260A) mutant or treatment with the mitogen-activated protein kinase (MAPK) inhibitor UO126 rescued their nuclear localization, interaction, and binding of the complex to chromatin in the HPK1Aras cells. In summary, we have demonstrated, using highly specific intracellular tagging methods in live and fixed cells, important alterations of the vitamin D signaling system in cancer cells in which the ras-raf-MAPK system is activated, suggesting that specific inhibition of this commonly activated pathway could be targeted therapeutically to enhance vitamin D efficacy.


Subject(s)
Keratinocytes/metabolism , Mediator Complex/metabolism , Neoplasms/drug therapy , Receptors, Calcitriol/metabolism , Retinoid X Receptors/metabolism , Vitamin D/therapeutic use , Cell Nucleus/chemistry , Cell Transformation, Neoplastic , Chromatin/metabolism , DNA/metabolism , Genes, ras , Humans , Keratinocytes/ultrastructure , Mediator Complex/analysis , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Phosphorylation , Receptors, Calcitriol/analysis , Retinoid X Receptors/analysis , Serine/metabolism , Signal Transduction
12.
ACS Med Chem Lett ; 8(2): 251-255, 2017 Feb 09.
Article in English | MEDLINE | ID: mdl-28197321

ABSTRACT

Lomibuvir (1) is a non-nucleoside, allosteric inhibitor of the hepatitis C virus NS5B polymerase with demonstrated clinical efficacy. Further development efforts within this class of inhibitor focused on improving the antiviral activity and physicochemical and pharmacokinetic properties. Recently, we reported the development of this series, leading to compound 2, a molecule with comparable potency and an improved physicochemical profile relative to 1. Further exploration of the amino amide-derived side chain led to a series of lactam derivatives, inspired by the X-ray crystal structure of related thiophene carboxylate inhibitors. This series, exemplified by 12f, provided 3-5-fold improvement in potency against HCV replication, as measured by replicon assays. The synthesis, structure-activity relationships, in vitro ADME characterization, and in vivo evaluation of this novel series are discussed.

13.
Mater Sci Eng C Mater Biol Appl ; 69: 598-608, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27612752

ABSTRACT

In the present investigation, simplex lattice mixture design was applied for formulation development and optimization of a controlled release dosage form of ketoprofen microspheres consisting polymers like ethylcellulose and Eudragit(®)RL 100; when those were formed by oil-in-oil emulsion solvent evaporation method. The investigation was carried out to observe the effects of polymer amount, stirring speed and emulsifier concentration (% w/w) on percentage yield, average particle size, drug entrapment efficiency and in vitro drug release in 8h from the microspheres. Analysis of variance (ANOVA) was used to estimate the significance of the models. Based on the desirability function approach numerical optimization was carried out. Optimized formulation (KTF-O) showed close match between actual and predicted responses with desirability factor 0.811. No adverse reaction between drug and polymers were observed on the basis of Fourier transform infrared (FTIR) spectroscopy and Differential scanning calorimetric (DSC) analysis. Scanning electron microscopy (SEM) was carried out to show discreteness of microspheres (149.2±1.25µm) and their surface conditions during pre and post dissolution operations. The drug release pattern from KTF-O was best explained by Korsmeyer-Peppas and Higuchi models. The batch of optimized microspheres were found with maximum entrapment (~90%), minimum loss (~10%) and prolonged drug release for 8h (91.25%) which may be considered as favourable criteria of controlled release dosage form.


Subject(s)
Chemistry, Pharmaceutical/methods , Ketoprofen/pharmacology , Microspheres , Polymers/chemistry , Analysis of Variance , Calorimetry, Differential Scanning , Drug Liberation , Kinetics , Microscopy, Electron, Scanning , Models, Theoretical , Particle Size , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared , Statistics as Topic , Surface Properties
14.
J Med Chem ; 59(13): 6293-302, 2016 07 14.
Article in English | MEDLINE | ID: mdl-27366941

ABSTRACT

The hepatitis C viral proteins NS3/4A protease, NS5B polymerase, and NS5A are clinically validated targets for direct-acting antiviral therapies. The NS5B polymerase may be inhibited directly through the action of nucleosides or nucleotide analogues or allosterically at a number of well-defined sites. Herein we describe the further development of a series of thiophene carboxylate allosteric inhibitors of NS5B polymerase that act at the thumb pocket 2 site. Lomibuvir (1) is an allosteric HCV NS5B inhibitor that has demonstrated excellent antiviral activity and potential clinical utility in combination with other direct acting antiviral agents. Efforts to further explore and develop this series led to compound 23, a compound with comparable potency and improved physicochemical properties.


Subject(s)
Antiviral Agents/pharmacology , Drug Discovery , Hepacivirus/drug effects , Thiophenes/pharmacology , Viral Nonstructural Proteins/antagonists & inhibitors , Allosteric Regulation/drug effects , Antiviral Agents/chemical synthesis , Antiviral Agents/chemistry , Cyclohexanols/chemistry , Cyclohexanols/pharmacology , Dose-Response Relationship, Drug , Hepacivirus/enzymology , Microbial Sensitivity Tests , Models, Molecular , Molecular Structure , Structure-Activity Relationship , Thiophenes/chemical synthesis , Thiophenes/chemistry , Viral Nonstructural Proteins/metabolism , Virus Replication/drug effects
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