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1.
Microb Pathog ; 179: 106093, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37004966

RESUMO

Opportunistic pathogenic bacteria and their pathogenicity linked with biofilm infections become a severe issue as they resist the actions of multiple antimicrobial drugs. Naturally derived drugs having antibiofilm properties are more effective than chemically synthesized drugs. The plant derived essential oils are a rich source of phytoconstituents with widespread pharmacological values. In the present investigation, a major phytoconstituent, 2-Phenyl Ethyl Methyl Ether (PEME) of Kewda essential oil extracted from the flowers of Pandanus odorifer was explored for its prospective antimicrobial and anti-biofilm properties against ESKAPE pathogenic bacterial strains, Staphylococcus aureus and MTCC 740. The minimum inhibitory concentration (MIC) of PEME was found to be 50 mM against the tested bacterial strains. A gradual decrease in biofilm production was observed when PEME was treated with the sub-MIC concentration. The reduction in biofilm formation was noticeable from qualitative assay i.e., Congo Red Agar Assay (CRA) and further quantified by crystal violet staining assay. The decline in exopolysaccharides production was quantified, with the highest inhibition against MTCC 740 with a decrease of 71.76 ± 4.56% compared to untreated control. From the microscopic analysis (light and fluorescence microscopic method), PEME exhibited inhibitory effect on biofilm formation on the polystyrene surface. The in silico studies stated that PEME could invariably bind to biofilm associated target proteins. Further, transcriptomic data analysis suggested the role of PEME in the down-regulation of specific genes, agrA, sarA, norA and mepR, which are critically associated with bacterial virulence, biofilm dynamics and drug resistance patterns in S. aureus. Further, qRT-PCR analysis validated the role of PEME on biofilm inhibition by relative downregulation of agrA, sarA, norA and mepR genes. Further, advanced in silico methodologies could be employed in future investigations to validate its candidature as promising anti-biofilm agent.


Assuntos
Anti-Infecciosos , Éteres Metílicos , Óleos Voláteis , Infecções Estafilocócicas , Humanos , Óleos Voláteis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus , Estudos Prospectivos , Infecções Estafilocócicas/microbiologia , Biofilmes , Anti-Infecciosos/farmacologia , Bactérias , Éteres Metílicos/farmacologia , Testes de Sensibilidade Microbiana
2.
Cell Mol Neurobiol ; 41(2): 279-292, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32318899

RESUMO

Epilepsy is a neurological disorder characterized by the occurrence of spontaneous and recurrent seizures. In post-traumatic epilepsy (PTE), the mechanism of epileptogenesis is very complex and seems to be linked with voltage-gated ion channels. Dehydroepiandrosterone (DHEA), a neurosteroid have shown beneficial effect against various neurological disorders. We investigated antiepileptic effect of DHEA with respect to expression of voltage-gated ion channels subtypes in iron-induced epilepsy. Iron (FeCl3) solution was intracartically injected to induce epilepsy in rats and DHEA was intraperitoneally administered for 21 days. Results showed markedly increased epileptiform seizures activity along with up-regulation of Nav1.1 and Nav1.6, and down-regulation of Cav2.1α at the mRNA and protein level in the cortex and hippocampus of epileptic rats. Moreover, the study demonstrated that these channels subtypes were predominantly expressed in the neurons. DHEA treatment has countered the epileptic seizures, down-regulated Nav1.1 and Nav1.6, and up-regulated Cav2.1α without affecting their cellular localization. In conclusion, the present study demonstrates antiepileptic potential of DHEA, escorted by regulation of Nav1.1, Nav1.6, and Cav2.1α subtypes in the neurons of iron-induced epileptic rats.


Assuntos
Canais de Cálcio/metabolismo , Desidroepiandrosterona/uso terapêutico , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Canais de Sódio/metabolismo , Animais , Canais de Cálcio/genética , Desidroepiandrosterona/farmacologia , Epilepsia/genética , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/metabolismo , Ferro , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Canais de Sódio/genética
3.
Plant Dis ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33761772

RESUMO

Wild species or crop wild relatives (CWRs) provide a unique opportunity to introduce novel traits and expand the genetic base of the cultivated pigeonpea (Bohra et al. 2010, 2020). Among the wild relatives of pigeonpea, Cajanus scarabaeoides is cross-compatible with cultivated pigeonpea (C. cajan). To identify the resistant sources for use in the pigeonpea breeding, the present study was conducted using 79 wild pigeonpea accessions at ICAR-Indian Institute of Pulses Research, Kanpur, India during 2016-17 and 2017-18 (Figures 1 a and b). The pigeonpea accessions belonged to three different genera Cajanus, Rhynchosia and Flemingia. During field scouting, seedlings were observed with foliar chlorosis and wilting (Fig. 2a). Infected stem tissue exhibited brown to black discoloration, followed by gradual plant drying, and ultimately plant death (Fig. 2b). Infected plants were collected from the field and pathological examination was performed in the laboratory conditions. Wilted plant parts were surface-disinfected with 1% sodium hypochlorite for two minutes and 5.0 mm size pieces of stem tissue were transferred to petri-dishes containing 90ml of Fusarium Specific Medium (FSM) (Nash and Snyder 1962) and incubated at 27oC. After 48 hrs of incubation, white to orange aerial mycelial growth was observed (Fig. 2c). The fungus was transferred to fresh FSM and purified by the single-spore technique (Choi et al. 1999). Macroconidia had four to six septa, slightly curved at the apex ranged from 20.0 to 25.0 × 3.0 to 5.5 µm (Fig. 2d). Microconidia were absent. The isolated fungus was putatively identified as belonging to the F. equiseti species complex based on colony morphology and macroconidia characteristics and size (Booth, 1977; Leslie and Summerell 2004). The pathogenicity test was conducted on 15-day old healthy seedlings of wild pigeonpea using 'root dip inoculation' and 'soil inoculation' technique (Haware and Nene 1994). Plant roots were immersed in a conidial suspension (6×106 conidia/ml water as determined by a hemocytometer) for 3-4 minutes (Marley and Hillocks 1996), while the roots of control plant were immersed in sterilized distilled water. A single spore culture of F. equiseti was grown on PDA-containing perti-dishes. Two actively grown mycelia discs (5 mm dia) from the periphery of 7-day old pure culture of F. equiseti were separately inoculated in 500 ml conical flasks containing 100g pigeonpea meal medium. The flasks were incubated at 28±2°C for 10 days. A fungus-soil mixture was prepared by mixing 200 g of inoculums with 2kg of autoclaved sand: soil mixture (3:7). Earthen pots having 15-cm diameter were sterilized by formalin (0.1%). These pots were then filled with fungus-soil mixture. Seeds sterilized with mercuric chloride (1%) were sown in each pot. Seeds sown in uninoculated pots served as control. Five seeds were sown in each pot with three replications. Disease symptoms developed 10 days after inoculation of wild pigeonpea plants in greenhouse. Symptoms were identical to those observed in the field. No symptoms were observed in control. Re-isolating the F. equiseti pathogen from the inoculated wild pigeonpea seedlings corroborated Koch's postulates. Reference cultures of three isolates of F. equiseti were deposited in Indian Type of Culture Collection (ITCC), Division of Plant Pathology, ICAR-Indian Agricultural Research Institute (IARI), New Delhi with the accession numbers ITCC8413, ITCC8414 and ITCC8415. Fungal genomic DNA was extracted through modified CTAB method (Murray and Thompson 1980). The ITS regions 1 and 2, including 5.8S ribosomal DNA (rDNA) region, and part of translation elongation factor 1-α (TEF) were amplified by using the ITS6F (GAAGGTGAAGTCGTAACAGG) and ITS4R (TCCTCCGCTTATTGATATGC) and tef (F: ATGGGTAAGGAAGACAAGAC; R: GGAAGTACCAGTGAATCATGTT) primers. BLASTn analysis of the sequences generated showed a 98.78% homology with F. equiseti. The sequences were deposited at GenBank (Accession numbers of ITS region: MF351849, MF351850, MF351851, and Tef region: MK259963, MK264345, MK264346). Phylogenetic analysis of the ITS and Tef region sequences revealed that all Fusarium isolates belong to the F. equiseti species complex and other available sequences of Fusarium spp. (Fig. 3). Occurrence of F. equiseti on various plant species is reported worldwide by several researchers (Liang et al. 2011; Ramachandra and Bhatt 2012; Prasad et al. 2017). To the best of our knowledge and based on the literature, this is the first report of wilt disease on wild pigeonpea in India, caused by F. equiseti (Corda) Sacc.

4.
Monaldi Arch Chest Dis ; 92(2)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34526725

RESUMO

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 has varied manifestation with multisystem involvement. Acute coronary syndrome in COVID-19 as a result of stent thrombosis is an uncommon entity and is often due to hypercoagulable state. A 40-year-old male was referred to us with acute onset chest pain. He also reported fever, sore throat and dry cough for six days which mandated testing for COVID-19 which turned out to be positive. He had a prior history of coronary artery disease with a drug eluting stent implanted two years back. An electrocardiogram was suggestive of acute anterior wall myocardial infarction while echocardiogram revealed hypokinesia of left anterior descending (LAD) artery territory. Coronary angiogram revealed non-occlusive thrombus in proximal LAD stent. A Thrombolysis in Myocardial Infarction (TIMI) III flow was restored following balloon angioplasty with a non-compliant balloon and use of glycoprotein (GP) IIb-IIIa receptor antagonist. A diagnosis of very late stent thrombosis subsequent to COVID-19 was made.


Assuntos
COVID-19 , Stents Farmacológicos , Trombose , Adulto , COVID-19/complicações , Teste para COVID-19 , Stents Farmacológicos/efeitos adversos , Humanos , Masculino , Inibidores da Agregação Plaquetária , SARS-CoV-2 , Stents/efeitos adversos , Trombose/diagnóstico por imagem , Trombose/etiologia
5.
J Org Chem ; 85(12): 8166-8175, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32453563

RESUMO

The first global method for the preparation of 3-phosphorylated-pyrroles, -furans, -thiophenes, and 4-phosphorylated 2,5-dihydropyridazines is reported. To achieve this, the first protocol for the direct synthesis of α-phosphorylated 1,4-diketones has been developed through a carbene-catalyzed Stetter reaction of vinylphosphonates and aldehydes. This is the first synthetic method for accessing 4-phosphorylated 2,5-dihydropyridazines. This process is metal-free and produces multifunctionalized heterocycles.

6.
J Org Chem ; 85(15): 10175-10181, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32662643

RESUMO

The stereoselective oxidative rearrangement of disubstituted unactivated olefins has been achieved using a hypervalent iodine(III) reagent. The aryl group undergoes 1,2-migration to give tert-α-arylated aldehydes (as acetals). The preparation of these aldehydes/acetals, especially containing a tert-benzylic stereocenter, has remained challenging. This migration-based method provides a complementary approach over the known α-substitution-based methods for accessing this class of molecules.

7.
Chemosphere ; 359: 142288, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38750729

RESUMO

Helicoverpa armigera, a ubiquitous polyphagous pest, poses a significant threat to global agriculture, causing substantial economic losses and demonstrating resistance to synthetic pesticides. This study investigates the potential of emamectin benzoate (EMB), an avermectin derivative, as an effective control agent against H. armigera. The larvae of the NBII-MP-NOC-01 strain of H. armigera were reared on an artificial diet. The impact of dietary EMB was examined on four midgut enzymes; alanine aminotransferase (ALT), aspartate aminotransferase (AST), acid phosphatase (ACP), and alkaline phosphatase (ALP). Results showed a dose-dependent and time-dependent reduction in ALT and AST activity, while an initial increase and subsequent decline in ACP and ALP activity at higher EMB concentrations. Computational modelling of enzyme structures and molecular docking studies revealed differential binding of EMB with the midgut enzymes. The strongest interaction was observed between EMB and ALT residues, contrasting with weakest interactions observed with AST. The study also showed that decreased activity of transaminases in H. armigera caused by EMB may be because of stability-activity trade-off, while in phosphatases reverse may be the case. This research provides crucial insights into the biochemical responses and the intricate insecticide-enzyme interactions in H. armigera caused by EMB exposure. This study lays the foundation for further research aimed at developing environmentally friendly approaches for managing H. armigera, addressing the challenges associated with conventional pesticides.


Assuntos
Fosfatase Ácida , Alanina Transaminase , Fosfatase Alcalina , Aspartato Aminotransferases , Inseticidas , Ivermectina , Larva , Simulação de Acoplamento Molecular , Mariposas , Animais , Ivermectina/análogos & derivados , Ivermectina/toxicidade , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Inseticidas/toxicidade , Inseticidas/química , Inseticidas/metabolismo , Fosfatase Alcalina/metabolismo , Fosfatase Ácida/metabolismo , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Helicoverpa armigera
8.
Nat Prod Res ; : 1-9, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353041

RESUMO

Gandhamardan has a rich heritage of floristic diversity with undocumented medicinal plants, called Anukta Dravya having immense pharmacological values. Among them, Pittosporum napaulense (DC.) Rehder & E. H. Wilson is an important medicinal plant with widespread pharmacological importance. The antioxidant potential, antibacterial and antibiofilm activities of P. napaulense (DC.) were evaluated. The ethanolic extract showed the highest share of phenolic and flavonoid contents responsible for DPPH and ABTS radical scavenging activity with an IC50 of 5.58 and 5.28 µg/ml, respectively. In addition, the extracts also showed antibacterial and antibiofilm properties against multidrug-resistant bacterial strains, Staphylococcus aureus and Shigella sp. The biological activities of P. napaulense (DC.) bark could be attributed to the presence of phytoconstituents such as Malabaricone C, Borapetoside B, Kanzonol R. as evident from UPLC-Q-TOF-MS analysis. Based on the bioactivities; this plant could be explored for the development of potential therapeutic drug candidates against severe bacterial diseases.

9.
Braz J Microbiol ; 54(3): 2349-2360, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37584890

RESUMO

The present study was conducted to characterize the native plant growth-promoting rhizobacteria (PGPRs) from the pulse rhizosphere of the Bundelkhand region of India. Twenty-four bacterial isolates belonging to nineteen species (B. amyloliquefaciens, B. subtilis, B. tequilensis, B. safensis, B. haynesii, E. soli, E. cloacae, A. calcoaceticus, B. valezensis, S. macrescens, P. aeruginosa, P. fluorescens, P. guariconensis, B. megaterium, C. lapagei, P. putida, K. aerogenes, B. cereus, and B. altitudinis) were categorized and evaluated for their plant growth-promoting potential, antifungal properties, and enzymatic activities to identify the most potential strain for commercialization and wider application in pulse crops. Phylogenetic identification was done on the basis of 16 s rRNA analysis. Among the 24 isolates, 12 bacterial strains were gram positive, and 12 were gram negative. Among the tested 24 isolates, IIPRAJCP-6 (Bacillus amyloliquefaciens), IIPRDSCP-1 (Bacillus subtilis), IIPRDSCP-10 (Bacillus tequilensis), IIPRRLUCP-5 (Bacillus safensis), IIPRCDCP-2 (Bacillus subtilis), IIPRAMCP-1 (Bacillus safensis), IIPRMKCP-10 (Bacillus haynesii), IIPRANPP-3 (Bacillus amyloliquefaciens), IIPRKAPP-5 (Enterobacter soli), IIPRAJCP-2 (Enterobacter cloacae), IIPRDSCP-11 (Acinetobacter calcoaceticus), IIPRDSCP-9 (Bacillus valezensis), IIPRMKCP-3 (Seratia macrescens), IIPRMKCP-1 (Pseudomonas aeruginosa), IIPRCKPP-3 (Pseudomonas fluorescens), IIPRMKCP-9 (Pseudomonas guariconensis), IIPRMKCP-8 (Bacillus megatirium), IIPRMWCP-9 (Cedecea lapagei), IIPRKUCP-10 (Pseudomonas putida), IIPRAMCP-4 (Klebsiella aerogenes), IIPRCKPP-7 (Enterobacter cloacae), IIPRAMCP-5 (Bacillus cereus), IIPRSHEP-6 (Bacillus subtilis), IIPRRSBa89 (Bacillus altitudinis) bacterial isolates, IIPRMKCP-9, IIPRAJCP-6, IIPRMKCP-10, IIPRAMCP-5, IIPRSHEP-6, and IIPRMKCP-3 showed the maximum antagonistic activity against Fusarium oxysporum f. sp. ciceris (FOC), Fusarium oxysporum f. sp. lentis (FOL), and Fusarium udum (FU) causing wilt disease of chickpea, lentil, and pigeonpea, respectively, and maximum plant growth-promoting enzyme (phosphatase), plant growth hormone (IAA), and siderophore production show promising results under greenhouse conditions. This study is the first report of bacterial diversity in the pulse-growing region of India.


Assuntos
Antifúngicos , Fusarium , Antifúngicos/farmacologia , Rizosfera , Filogenia , Bacillus subtilis/genética , Reguladores de Crescimento de Plantas , Pseudomonas aeruginosa , Doenças das Plantas/microbiologia
10.
Parasitol Res ; 111(1): 173-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22231268

RESUMO

The extracts from the peels of Citrus limetta were prepared using hexane and petroleum ether as the solvents. The larvicidal potential of each extract was assessed against dengue fever vector, Aedes aegypti, and malarial vector, Anopheles stephensi, by evaluating the toxicity effects on early fourth instars. Both the extracts were found effective against both the species. The bioassay with hexane extracts resulted in LC(50) values of 132.45 and 96.15 ppm against A. stephensi and A. aegypti, respectively; while the petroleum ether extracts from the C. limetta peels showed LC(50) values of 244.59 and 145.50 ppm, respectively. It revealed that the hexane extracts possessed 1.9-fold more larvicidal potential against A. stephensi and 1.5-fold more efficacy against A. aegypti as compared to the extracts obtained using petroleum ether as solvent. The data further revealed that the extracts were 1.4-1.7 times more effective against A. aegypti as compared to A. stephensi. The qualitative phytochemical study of the extracts showed the presence of terpenoids and flavonoids as the common phytochemical constituents in the extracts suggesting their possible role in the toxicity. Other constituents tested were not detected except alkaloids which were found to be present only in the petroleum ether extract. Further studies are needed to isolate and identify the active principles involved, their mode of action, formulated preparations for enhancing potency and stability, toxicity, and effects on non-target organisms and the environment. This could help in formulating efficient strategies for mosquito control.


Assuntos
Aedes/efeitos dos fármacos , Anopheles/efeitos dos fármacos , Citrus/química , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Alcaloides/análise , Animais , Feminino , Flavonoides/análise , Frutas/química , Índia , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Análise de Sobrevida , Terpenos/análise
11.
Indian J Exp Biol ; 50(2): 101-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22670472

RESUMO

L-deprenyl is considered to protect against age-related cognitive deficits by improving long-term learning/memory in the aged brain. The CA1 and CA3 hippocampal areas are the sites at which initial learning and memory processes occur. Chronic deprenyl treatment significantly augmented the basal electrical firing rate (multiple-unit action potentials), and Na+, K(+)-ATPase and protein kinase C activities of both CA1 and CA3 indicating that the drug increased the excitability of CA1 and CA3. The increase, however, was much greater in CA1 than in CA3 suggesting that deprenyl can improve longer-term learning in aged animals by its excitability-enhancing action in CA1. The drug also countered the ageing-related loss of hippocampal protein kinase C activity.


Assuntos
Envelhecimento/fisiologia , Região CA1 Hipocampal/efeitos dos fármacos , Região CA3 Hipocampal/efeitos dos fármacos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Proteína Quinase C/metabolismo , Selegilina/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Potenciais de Ação/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Animais , Região CA1 Hipocampal/enzimologia , Região CA1 Hipocampal/fisiologia , Região CA3 Hipocampal/enzimologia , Região CA3 Hipocampal/fisiologia , Eletroencefalografia , Aprendizagem/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Análise de Regressão
12.
Front Physiol ; 13: 1031285, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311240

RESUMO

Aedes aegypti is responsible for the global spread of several ailments such as chikungunya, dengue, yellow fever, and Zika. The use of synthetic chemicals is the primary intervention in mosquito management. However, their excessive utilization resulting in the spread of toxic ingredients in the environment and posing threats to beneficial organisms has prompted the recommendation for the use of biologically synthesized nanocomposites as a promising approach for vector control. Silver nanocomposites were synthesized using leaf (AL-AgNCs) and stem (AS-AgNCs) extracts of Achyranthes aspera. The early fourth instars of A. aegypti were exposed to lethal doses of these nanocomposites to evaluate their effects on larval development, behavior, morphology, and mid-gut histoarchitecture. The cellular damage and deposition of nanocomposite residues in the mid-gut were studied using light and transmission electron microscopy. The A. aspera silver nanocomposite (AA-AgNC)-exposed larvae exhibited dose-dependent extended duration of development and diminished adult emergence, but did not exhibit modified behavior. Intense damage to the cuticle membrane and slight contraction in the internal membrane of anal papillae were noticed. Morphologically, the mid-gut appeared disorganized, darkly pigmented, and shrunk. Histological investigations of the mid-gut revealed significantly disordered internal architecture with lysed cells, damaged peritrophic membrane and microvilli, disintegrated epithelial layer, and a ruptured and displaced basement membrane. Visualization of the larval mid-gut through TEM showed severe cellular damage and aggregation of black spots, indicating the deposition of silver particles released by AA-AgNCs. The investigations revealed the bio-efficacy of A. aspera-mediated AgNCs against A. aegypti inducing stomach and contact toxicity in the larvae. The utilization of AA-AgNCs is recommended for A. aegypti management as a safe and effective intervention.

13.
Nanotechnology ; 22(46): 465701, 2011 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-22024967

RESUMO

This paper deals with the preparation of graphene oxide-ferrofluid-cement nanocomposites to evaluate the electromagnetic interference (EMI) shielding effectiveness (SE) in the 8.2-12.4 GHz frequency range. It has been observed that incorporation of graphene oxide (30 wt%) along with an appropriate amount of ferrofluid in the cement matrix leads to a shielding effectiveness of 46 dB (>99% attenuation).The presence of graphene oxide and ferrofluid in the cement leads to strong polarizations and magnetic losses that consequently result in higher shielding effectiveness compared to pristine cement. The resulting nanocomposites have shown Shore hardness of 54 and dc conductivity of 10.40 S cm( - 1). SEM reveals the homogeneous dispersion of graphene oxide and ferrofluid in the cement matrix.

14.
Epilepsy Behav ; 19(3): 264-71, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20801087

RESUMO

In the study described here, the antiepileptic effect of dehydroepiandrosterone (DHEA) treatment on iron-induced focal epileptiform activity in the rat brain was investigated. DHEA is a neuroactive corticosteroid hormone synthesized both in the adrenal cortex and in the brain. Its antioxidant properties are well known. As oxidative stress seems to play a major role in epileptogenesis in the iron-induced model of posttraumatic epilepsy, it was of interest to examine whether DHEA would exert antiepileptic activity. DHEA at a dose of 30 mg/kg/day administered intraperitoneally for 7, 14, and 21 days to iron-induced epileptic rats prevented epileptiform electrophysiological activity. Morris water maze and open-field tests on iron-induced epileptic rats revealed that DHEA also prevented behavioral alterations related to epileptiform activity. Thus, DHEA attenuated the cognitive defects produced by epileptic activity. Moreover, alterations in epileptogenesis-related biochemical parameters-lipid peroxidation, protein oxidation and Na(+), K(+)-ATPase (sodium pump) activity--were also countered by DHEA.


Assuntos
Anticonvulsivantes/uso terapêutico , Encéfalo/efeitos dos fármacos , Desidroepiandrosterona/uso terapêutico , Epilepsia/patologia , Epilepsia/prevenção & controle , Análise de Variância , Animais , Modelos Animais de Doenças , Eletroencefalografia/métodos , Epilepsia/induzido quimicamente , Epilepsia/fisiopatologia , Comportamento Exploratório/efeitos dos fármacos , Ferro/efeitos adversos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Análise de Regressão , ATPase Trocadora de Sódio-Potássio/metabolismo , Fatores de Tempo
15.
Biodegradation ; 21(6): 967-78, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20401684

RESUMO

Four different bacterial strains were isolated from pulp and paper mill sludge in which one alkalotolerant isolate (LP1) having higher capability to remove color and lignin, was identified as Bacillus sp. by 16S RNA sequencing. Optimization of process parameters for decolorization was initially performed to select growth factors which were further substantiated by Taguchi approach in which seven factors, % carbon, % black liquor, duration, pH, temperature, stirring and inoculum size, at two levels, applying L-8 orthogonal array were taken. Maximum color was removed at pH 8, temperature 35°C, stirring 200 rpm, sucrose (2.5%), 48 h, 5% (w/v) inoculum size and 10% black liquor. After optimization 2-fold increase in color and lignin removal from 25-69% and 28-53%, respectively, indicated significance of Taguchi approach in decolorization and delignification of lignin in pulp and paper mill effluent. Enzymes involved in the process of decolorization of effluent were found to be xylanase (54 U/ml) and manganese peroxidase (28 U/ml). Treated effluent was also evaluated for toxicity by Comet assay using Saccharomyces cerevisiae MTCC 36 as model organism, which indicated 58% reduction after treatment by bacterium.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Álcalis/farmacologia , Bactérias/isolamento & purificação , Resíduos Industriais/análise , Papel , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Análise de Variância , Bacillus/efeitos dos fármacos , Bacillus/enzimologia , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Cor , Ensaio Cometa , DNA Bacteriano/análise , Lignina/metabolismo , Dados de Sequência Molecular , Filogenia , Reprodutibilidade dos Testes , Poluentes Químicos da Água/toxicidade
16.
Chem Commun (Camb) ; 56(52): 7155-7158, 2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32462158

RESUMO

N-heterocyclic carbene (NHC) catalyzed direct access to enantioenriched 4-phosphorylated δ-lactones from ß-phosphorylenones and enals has been achieved. The sterically demanding ß-phosphonate-substituted enones, having competing regiomeric reaction centres, have remained elusive so far in intermolecular cycloaddition reactions under NHC catalysis. All the products were obtained in excellent yield and enantioselectivity. These phosphorylated δ-lactones could be transformed into challenging multi-functionalized chiral esters and amides loaded with a ß-ketophosphonate functionality.

17.
Int J Biol Macromol ; 122: 127-136, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30340003

RESUMO

In order to optimize drug action, new drug formulations have been developed based upon the prodrug approach. This study was inspired by the increasing interest in the field of macromolecular prodrugs and Piroxicam maleate was used as a model drug. A total of five prodrugs were synthesized using beta cyclodextrin, chitosan, pectin, egg albumin, bovine serum albumin. The synthesized conjugates were characterized on the basis of UV, IR and NMR techniques. In-vitro hydrolysis studies were carried out at pH 1.2, pH 7.4, pH 9.0 and in 80% human plasma followed by in-vivo evaluation of analgesic, anti-inflammatory and anti-ulcerogenic potential. The extent of hydrolysis was found to be proportional to increase in pH. Beta cyclodextrin conjugate was found to possess significant analgesic activity whereas chitosan conjugate was found to be the best anti-inflammatory. Pectin conjugate provided maximum protection against ulcers.


Assuntos
Albuminas/química , Quitosana/química , Pectinas/química , Piroxicam/química , Piroxicam/farmacologia , Estômago/efeitos dos fármacos , beta-Ciclodextrinas/química , Animais , Bovinos , Técnicas de Química Sintética , Citoproteção/efeitos dos fármacos , Composição de Medicamentos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Masculino , Camundongos , Piroxicam/síntese química , Piroxicam/metabolismo , Pró-Fármacos/metabolismo , Ratos , Estômago/citologia , Úlcera Gástrica/prevenção & controle
18.
Curr Top Med Chem ; 19(10): 812-830, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30977454

RESUMO

The developing resistance in fungi has become a key challenge, which is being faced nowadays with the available antifungal agents in the market. Further search for novel compounds from different sources has been explored to meet this problem. The current review describes and highlights recent advancement in the antifungal drug aspects from plant and marine based sources. The current available antifungal agents act on specific targets on the fungal cell wall, like ergosterol synthesis, chitin biosynthesis, sphingolipid synthesis, glucan synthesis etc. We discuss some of the important anti-fungal agents like azole, polyene and allylamine classes that inhibit the ergosterol biosynthesis. Echinocandins inhibit ß-1, 3 glucan synthesis in the fungal cell wall. The antifungals poloxins and nikkomycins inhibit fungal cell wall component chitin. Apart from these classes of drugs, several combinatorial therapies have been carried out to treat diseases due to fungal resistance. Recently, many antifungal agents derived from plant and marine sources showed potent activity. The renewed interest in plant and marine derived compounds for the fungal diseases created a new way to treat these resistant strains which are evident from the numerous literature publications in the recent years. Moreover, the compounds derived from both plant and marine sources showed promising results against fungal diseases. Altogether, this review article discusses the current antifungal agents and highlights the plant and marine based compounds as a potential promising antifungal agents.


Assuntos
Antifúngicos/farmacologia , Bactérias/química , Fungos/efeitos dos fármacos , Phaeophyceae/química , Plantas/química , Poríferos/química , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Fungos/química , Humanos , Testes de Sensibilidade Microbiana
19.
Brain Res Bull ; 153: 181-190, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31472186

RESUMO

Epilepsy is a neurological disorder characterized by the prevalence of spontaneous and recurrent seizures. Oxidative stress has been recognized as an intrinsic mechanism for the initiation and progression of epilepsy. In the present study, we investigated the neuroprotective effect of dehydroepiandrosterone (DHEA) against iron-induced epilepsy in rats. Animals were made epileptic by intracortical injection of FeCl3 (5 µl of 100 mM), and DHEA (30 mg/kg b. wt., for 7, 14, and 21 days) was administered intraperitoneally. The results showed electrophysiological alterations, excessive oxidative damage, diminished antioxidant defence and induction of apoptosis in the cortex and hippocampus of epileptic rats. Expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase-1 (NQO-1) was downregulated in both brain regions. While, DHEA treatment for 14 and 21 days has counteracted oxidative stress, reduced neuronal apoptosis and improved electrophysiological changes along with upregulation of Nrf2, HO-1, and NQO-1. In conclusion, our findings demonstrate that neuroprotective effect of DHEA against iron-induced epilepsy might be escorted by the alleviation of oxidative stress through Nrf2-mediated signal pathway.


Assuntos
Apoptose/efeitos dos fármacos , Desidroepiandrosterona/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Desidroepiandrosterona/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Heme Oxigenase-1/metabolismo , Hipocampo/efeitos dos fármacos , Ferro/metabolismo , Masculino , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Oxirredução , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Indian J Exp Biol ; 46(12): 852-4, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19245184

RESUMO

Influence of exogenously administered dehydroepiandrosterone (DHEA) on the activity of Na+ K+ ATPase was investigated in synaptosomal fraction from cerebral cortex, cerebellum, hippocampus and medulla regions of brain of 12 and 22 months old rats. DHEA was administered daily at the dose of 30 mg/kg/body wt, intraperitonially (ip) in both the age groups of rats for 1 month. Results showed that Na+ K+ ATPase activity, increased in DHEA treated rats in both the age groups. In terms of per cent increase, 22 months old animals showed significant increase in Na+ K+ ATPase activity in the synaptosomal fraction of all the four brain regions than in 12 months old DHEA-treated rats. This showed that exogenous DHEA modulated the activity of Na+ K+ ATPase and also protected the age-related loss of membrane integrity and functions. It was concluded that exogenous DHEA might be beneficial in terms of neuroprotection against age-related loss of Na+ K+ ATPase mediated brain functions like learning and memory.


Assuntos
Envelhecimento/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/farmacologia , Inibidores Enzimáticos/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Inibidores Enzimáticos/administração & dosagem , Masculino , Ratos , Ratos Wistar , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores
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