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1.
Environ Res ; 217: 114621, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36347396

RESUMO

The rapid industrialization of the world is disparagingly manipulating our environment and natural ecosystem. The researchers are taking keen interest to invent novel material as photocatalyst for non-degradable organic pollutants. Solar energy-driven practices employing semiconductors are a novel approach towards wastewater remediation. Here in, we successfully synthesized a vigorous photocatalysts comprising of g-C3N4 and doped ZnO-W/M (M = Co, Ce, Yb, Sm) by co-precipitation followed by metals doping via calcination approach. The structural, morphological, and photocatalytic applications for organic pollutants of synthesized heterostructure nanocomposites were examined by XRD, FTIR, SEM, EDX and UV visible spectrophotometer. Diffraction peaks attributed to both g-C3N4 and ZnO-W were detected in the XRD spectra. The FTIR spectra also inveterate the formation of g-C3N4/ZnO-W/M composites. The SEM images reveal an agglomerated morphology and EDS analysis also confirmed close contact between g-C3N4, ZnO-W and doped metals. The abridged energy band gap of g-C3N4/ZnO-W/M (M = Ce, Yb, Sm, Co) nanocomposites calculated via Tauc plot are 2.68, 2.88, 3.24 and 3.29 eV respectively. Narrowing of bandgap is considered an imperative triumph for the degradation of industrial effluents. The photocatalytic activity was performed against four different dyes and follows the trend Ce > Yb > Sm > Co. The recyclability tests were carried out for different dyes and no substantial catalytic activity loss was observed even after the fourth experimental run, which proves that reported ternary heterojunctions exhibit high mechanical stability and reusability.The species trapping experiment exposed that generated h+ are the principal active specie for dye photodegradation reactions. This work disseminates a novel photocatalyst for the removal of synthetic dyes.


Assuntos
Nanocompostos , Óxido de Zinco , Óxido de Zinco/química , Ecossistema , Catálise , Nanocompostos/química , Corantes
2.
Sensors (Basel) ; 23(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36850954

RESUMO

Fifth generation (5G) is a recent wireless communication technology in mobile networks. The key parameters of 5G are enhanced coverage, ultra reliable low latency, high data rates, massive connectivity and better support to mobility. Enhanced coverage is one of the major issues in the 5G and beyond 5G networks, which will be affecting the overall system performance and end user experience. The increasing number of base stations may increase the coverage but it leads to interference between the cell edge users, which in turn impacts the coverage. Therefore, enhanced coverage is one of the future challenging issues in cellular networks. In this survey, coverage enhancement techniques are explored to improve the overall system performance, throughput, coverage capacity, spectral efficiency, outage probability, data rates, and latency. The main aim of this article is to highlight the recent developments and deployments made towards the enhanced network coverage and to discuss its future research challenges.

3.
Health Info Libr J ; 40(1): 103-108, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36722458

RESUMO

This Regular Feature is based on a PhD study assessing the level of health literacy among university students in Pakistan. A cross-sectional survey was carried out using the validated European Health Literacy Survey (HLS-EU-Q) and non-parametric tests used to analyse data with the aim of determining the influence of personal determinants on health literacy skills. The findings of the study concluded that the population had a low health literacy level with limited skills in accessing, understanding, appraising and applying information for health care. Gender, age, and native languages, all had a statistically significant influence on health literacy skills. Practical implications are presented for the role of university libraries in supporting the development of health literacy in their undergraduate student populations are presented, including the need for the provision of health information in native languages.


Assuntos
Letramento em Saúde , Humanos , Paquistão , Estudos Transversais , Prevalência , Inquéritos e Questionários , Estudantes
4.
Vet Med (Praha) ; 68(6): 238-245, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37982002

RESUMO

The present study was aimed at measuring the concentration of aflatoxin M1 (AFM1) in the milk of Holstein Friesian cows, its effect on the milk quality and seasonal trends, as well as to investigate the efficacy of a commercial clay-based toxin binder. For this purpose, milk samples from dairy cows (n = 72) were collected and assayed for AFM1 before employing a clay-based toxin binder. The milk samples (n = 72) were collected from selected animals, revealing that 69.4% of the milk samples had AFM1 levels above the United States permissible limit (0.5 µg/kg). The incidence of AFM1 in milk during the winter and summer was 82.5% and 53.1%, respectively. Owing to the presence of AFM1, the level of milk fat, solids-not-fat, and protein were found to be low. Subsequently, the affected animals were divided into two groups, i.e., AFM1 positive control (n = 10) and the experimental group (n = 40). The experimental group of animals were fed the clay-based toxin binder at 25 g/animal/day. A progressive decrease of 19.8% in the AFM1 levels was observed on day 4 and on day 7 (53.6%) in the treatment group. Furthermore, the fat, solids-non-fat and protein increased significantly in the milk. In conclusion, a high level of AFM1 contamination occurs in the milk in Pakistan, affecting the quality of the milk production. Clay-based toxin binders may be used to ensure the milk quality and to protect the animal and consumer health.

5.
Vet Med (Praha) ; 68(10): 385-391, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38028205

RESUMO

Enzootic bovine leucosis is caused by bovine leukaemia virus (BLV), a Deltaretrovirus belonging to the family Retroviridae. BLV causes huge economic losses to the dairy industry in the form of decreased milk production, premature culling, and poor reproductive performance of the animals. The aim of the present study was to determine the seroprevalence of BLV infection in buffalo in two districts of Punjab, Pakistan. A total of 384 samples were collected and analysed using a commercial indirect enzyme-linked immunosorbent assay (ELISA) to investigate the seroprevalence of BLV through the detection of the anti-BLV gp51 antibody. A predesigned data questionnaire proforma was employed to find out the association of risk factors with disease. Overall, 18.2% of buffaloes were seropositive for BLV in the study population. The results revealed a significant association (P < 0.05) of age with BLV infection. Furthermore, milk yield and pregnancy had a significant association with the seroprevalence of BLV infection in buffalo whereas no significant association was found with sex, breeding, and health status. Biochemical and oxidative stress markers revealed a significant decrease in liver enzymes alanine transaminase (ALT) and aspartate transaminase (AST), glutathione peroxidase (GPX), and superoxide dismutase (SOD) in seropositive animals as compared to healthy animals. It is concluded that BLV has a considerable prevalence in buffalo in Punjab, Pakistan and there is a dire need to investigate the disease epidemiology at both national and international levels and strategies should be developed to implement an effective control program.

6.
Chem Rec ; 22(7): e202100280, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34921492

RESUMO

The rapid development of flexible and wearable optoelectronic devices, demanding the superior, reliable, and ultra-long cycling energy storage systems. But poor performances of electrode materials used in energy devices are main obstacles. Recently, single-atom catalysts (SACs) are considered as emerging and potential candidates as electrode materials for battery devices. Herein, we have discussed the recent methods for the fabrication of SACs for rechargeable metal-air batteries, metal-CO2 batteries, metal-sulfur batteries, and other batteries, following the recent advances in assembling and performance of these batteries by using SACs as electrode materials. The role of SACs to solve the bottle-neck problems of these energy storage devices and future perspectives are also discussed.

7.
Molecules ; 26(21)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34771081

RESUMO

Heteroatom doping is considered an efficient strategy when tuning the electronic and structural modulation of catalysts to achieve improved performance towards renewable energy applications. Herein, we synthesized a series of carbon-based hierarchical nanostructures through the controlled pyrolysis of Co-MOF (metal organic framework) precursors followed by in situ phosphidation. Two kinds of catalysts were prepared: metal nanoparticles embedded in carbon nanotubes, and metal nanoparticles dispersed on the carbon surface. The results proved that the metal nanoparticles embedded in carbon nanotubes exhibit enhanced ORR electrocatalytic performance, owed to the enriched catalytic sites and the mass transfer facilitating channels provided by the hierarchical porous structure of the carbon nanotubes. Furthermore, the phosphidation of the metal nanoparticles embedded in carbon nanotubes (P-Co-CNTs) increases the surface area and porosity, resulting in faster electron transfer, greater conductivity, and lower charge transfer resistance towards ORR pathways. The P-Co-CNT catalyst shows a half-wave potential of 0.887 V, a Tafel slope of 67 mV dec-1, and robust stability, which are comparatively better than the precious metal catalyst (Pt/C). Conclusively, this study delivers a novel path for designing multiple crystal phases with improved catalytic performance for energy devices.

8.
Molecules ; 26(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34577105

RESUMO

Granulosa cells (GCs) are essential for follicular growth, development, and atresia. The orexin-A (OXA) neuropeptide is widely involved in the regulation of various biological functions. OXA selectively binds to orexin receptor type 1 (OX1R) and mediates all its biological actions via OX1R. This study aimed to explore the expression of OXA and OX1R and their regulatory role in GCs proliferation, cell cycle progression, apoptosis, oocyte maturation, and underlying molecular mechanisms of these processes and elucidate its novel signaling pathway. Western blotting and RT-qPCR showed that OXA and OX1R were expressed during different developmental stages of GCs, and siRNA transfection successfully inhibited the expression of OX1R at the translational and transcriptional levels. Flow cytometry revealed that OX1R knockdown upregulated GCs apoptosis and triggered S-phase arrest in cell cycle progression. RT-qPCR and Western blotting showed significantly reduced expression of Bcl-2 and elevated expression of Bax, caspase-3, TNF-α, and P21 in OX1R-silenced GCs. Furthermore, the CCK-8 assay showed that knockdown of OX1R suppressed GCs proliferation by downregulating the expression of PCNA, a proliferation marker gene, at the translational and transcriptional levels. Western blotting revealed that knockdown of OX1R resulted in a considerable decrease of the phosphorylation level of the AKT and ERK1/2 proteins, indicating that the AKT/ERK1/2 pathway is involved in regulating GCs proliferation and apoptosis. In addition, OX1R silencing enhanced the mRNA expression of GDF9 and suppressed the mRNA expression of BMP15 in mouse GCs. Collectively, these results reveal a novel regulatory role of OXA in the development of GCs and folliculogenesis by regulating proliferation, apoptosis, and cell cycle progression. Therefore, OXA can be a promising therapeutic agent for female infertility.


Assuntos
Células da Granulosa/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Orexinas/fisiologia , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Ciclo Celular/genética , Ciclo Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Regulação para Baixo/genética , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/fisiologia , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Receptores de Orexina/genética , Receptores de Orexina/metabolismo , Orexinas/metabolismo , Folículo Ovariano/efeitos dos fármacos , Cultura Primária de Células
9.
Pak J Pharm Sci ; 32(5): 2003-2010, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31813864

RESUMO

The aims of the present investigation were to assess the antibacterial, antifungal, enzyme inhibition and hemolytic activities of various fractions of Rhynchosia pseudo-cajan Cambess. The methanolic extract of the plant was dissolved in the water (distilled) and then partitioned with the n-hexane, chloroform, EtOAc and n-BuOH sequentially. Antibacterial activity was checked against Escherichia coli, Pasturella multocida, Bacillus subtilis and Staphylococcus aureus by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Chloroform and ethyl acetate soluble fractions showed good activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. These fractions also showed good MIC values. The n-butanol soluble and remaining aqueous fraction also showed good activity against some strains. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the disc diffusion method using fluconazole, a standard antifungal drug, as positive control. Chloroform, n-butanol and ethyl acetate soluble fraction showed good activity only against G. lucidum. Enzyme inhibition studies were done against four enzymes i.e. α-glucosidase, butyrylcholinesterase, acetyl cholinesterase and lipoxygenase. Aqueous fraction possessed very good activity against α-glucosidase, even greater than acarbose, a reference standard drug. Its IC50 value was found as 29.81±0.12 µg/ml as compared to acarbose having IC50 38.62±0.04 µg/ml. Chlroform and ethyl acetate soluble fractions also showed good activity against α-glucosidase. Ethyl acetate soluble and remaining aqueous fractions showed good activity against lipoxygenase. All the studied fractions showed very less toxicity i.e. <2.5%.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Fabaceae/química , Hemólise/efeitos dos fármacos , Hemolíticos/farmacologia , Extratos Vegetais/farmacologia , 1-Butanol/química , Bactérias/efeitos dos fármacos , Clorofórmio/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Fungos/efeitos dos fármacos , Hexanos/química , Testes de Sensibilidade Microbiana/métodos , Fitoterapia/métodos
10.
Pak J Pharm Sci ; 32(5): 1957-1964, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31813858

RESUMO

The present study comprises the synthesis of a new series of benzenesulfonamides derived from N-sulfonation of 2-(4-methoxyphenyl)-1-ethanamine (1). The synthesis was initiated by the reaction of 2-(4-methoxyphenyl)-1-ethanamine (1) with benzenesulfonyl chloride (2), to yield N-(4-methoxyphenethyl)benzenesulfonamide (3). This parent molecule 3 was subsequently treated with various alkyl/aralkyl halides (4a-j) in N,N-dimethylformamide (DMF) and in the presence of a weak base lithium hydride (LiH) to obtain various N-(alkyl/aralkyl)-N-(4-methoxyphenethyl) benzenesulfonamides (5a-j). The characterization of these derivatives was carried out by spectroscopic techniques like IR, 1H-NMR, and 13C-NMR. Elemental analysis also supported this data. The biofilm inhibitory action of all the synthesized compounds was carried out on Escherichia coli and some of the compounds were identified to be very suitable inhibitors of this bacterial strain. Furthermore, the molecules were also tested for their cytotoxicity behavior to assess their utility as less cytotoxic therapeutic agents.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Biofilmes/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/química , Benzenossulfonamidas
11.
Microb Pathog ; 102: 133-142, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27916692

RESUMO

Neutralization of bacterial cell surface potential using nanoscale materials is an effective strategy to alter membrane permeability, cytoplasmic leakage, and ultimate cell death. In the present study, an attempt was made to prepare biogenic silver nanoparticles using biomolecules from the aqueous rhizome extract of Coptis Chinensis. The biosynthesized silver nanoparticles were surface modified with chitosan biopolymer. The prepared silver nanoparticles and chitosan modified silver nanoparticles were cubic crystalline structures (XRD) with an average particle size of 15 and 20 nm respectively (TEM, DLS). The biosynthesized silver nanoparticles were surface stabilized by polyphenolic compounds (FTIR). Coptis Chinensis mediated silver nanoparticles displayed significant activity against E. coli and Bacillus subtilus with a zone of inhibition 12 ± 1.2 (MIC = 25 µg/mL) and 18 ± 1.6 mm (MIC = 12.50 µg/mL) respectively. The bactericidal efficacy of these nanoparticles was considerably increased upon surface modification with chitosan biopolymer. The chitosan modified biogenic silver nanoparticles exhibited promising activity against E. coli (MIC = 6.25 µg/mL) and Bacillus subtilus (MIC = 12.50 µg/mL). Our results indicated that the chitosan modified silver nanoparticles were promising agents in damaging bacterial membrane potential and induction of high level of intracellular reactive oxygen species (ROS). In addition, these nanoparticles were observed to induce the release of the high level of cytoplasmic materials especially protein and nucleic acids into the media. All these findings suggest that the chitosan functionalized silver nanoparticles are efficient agents in disrupting bacterial membrane and induction of ROS leading to cytoplasmic leakage and cell death. These findings further conclude that the bacterial-nanoparticles surface potential modulation is an effective strategy in enhancing the antibacterial potency of silver nanoparticles.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/administração & dosagem , Prata , Antibacterianos/química , Bactérias/metabolismo , Bactérias/ultraestrutura , Potenciais da Membrana/efeitos dos fármacos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
12.
Acta Chim Slov ; 64(1): 159-169, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28380217

RESUMO

The aim of the research work was to synthesize different biologically active carbamate derivatives bearing 2-furoyl-1-piperazine and having modest toxicity. The synthesis was completed as a multiple sequence. The structural confirmation of all the synthesized compounds was obtained by EI-MS, IR and 1H-NMR spectral data. The enzyme inhibition and antibacterial potential of the synthesized compounds was evaluated. To find the utility of the prepared compounds as possible therapeutic agents their cytotoxicity was also checked. All the compounds were active against acetylcholinesterase enzyme, especially 12 and 14 showed very good inhibitory potential relative to Eserine, a reference standard. Almost all the compounds showed good activities against both Gram-positive and Gram-negative bacterial strains.


Assuntos
Antibacterianos/farmacologia , Carbamatos/síntese química , Carbamatos/farmacologia , Piperazinas/química , Acetilcolinesterase/efeitos dos fármacos , Butirilcolinesterase/efeitos dos fármacos , Carbamatos/química , Hemólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho
13.
Pak J Pharm Sci ; 29(4): 1307-15, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27393454

RESUMO

The biological potential of N'-substituted-2-(5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-ylthio)acetohydrazide (8a-p) has been evaluated against bacterial strains of Gram-negative and Gram-positive bacteria. The multistep synthesis involved the conversion of 3-chlorobenzoic acid (1) to ethyl 3-chlorobenzoate (2), 3-chlorobenzohydrazide (3), 5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-thiol (4), ethyl 2-(5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-ylthio) acetate (5) and 2-(5-(3-chlorophenyl)-1,3,4-Oxadiazol-2-ylthio)acetohydrazide (6). The last step involved the reaction of 6 and aryl aldehydes, 7a-p, in methanol to synthesize the Schiff bases, 8a-p, with better yields. The structures of all the molecules were corroborated by spectral analysis. The Schiff bases were further evaluated for the antibacterial activity and found to be moderately good inhibitors of bacterial strains of Gram-bacteria.


Assuntos
Antibacterianos/síntese química , Hidrazinas/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Hidrazinas/química , Hidrazinas/farmacologia
14.
Pak J Pharm Sci ; 29(3): 801-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27166551

RESUMO

A new series of N-substituted derivatives of 2-{(5-phenyl-1,3,4-Oxadiazol-2-yl)sulfanyl}acetamides was synthesized. The synthesis was carried out by converting benzoic acid (1) into ethyl benzoate (2), benzohydrazide (3) and then 5-pheny-1,3,4-Oxadiazol-2-thiol (4) step by st0ep. The target compounds 6a-p were synthesized by reaction of compound 4 with equimolar ratios of different N-alkyl/aryl substituted 2-bromoacetamide (5a-p) in the presence of DMF and sodium hydride (NaH). The spectral (EI-MS, IR, (1)H-NMR) characterization of all the synthesized compounds reveal their successful synthesis. The compounds were also screened for antimicrobial & hemolytic activity and most of them were found to be active against the selected microbial species at variable extent relative to reference standards. But 6h was the most active against the selected panel of microbes. This series showed less toxicity and may be considered for further biological screening and application trial except 6m, possessing higher cytotoxicity.


Assuntos
Acetamidas/síntese química , Acetamidas/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Desenho de Fármacos , Hemolíticos/síntese química , Hemolíticos/farmacologia , Oxidiazóis/síntese química , Oxidiazóis/farmacologia , Acetamidas/toxicidade , Anti-Infecciosos/toxicidade , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Relação Dose-Resposta a Droga , Hemólise/efeitos dos fármacos , Hemolíticos/toxicidade , Humanos , Espectrometria de Massas , Estrutura Molecular , Oxidiazóis/toxicidade , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
15.
Pak J Pharm Sci ; 29(1): 27-34, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26826837

RESUMO

The most emerging class among the heterocyclic compounds is 1,3,4-oxadiazoles for their diverse biological activities. In the present research work, piperonylic acid (1) was converted consecutively into corresponding ester (2), hydrazide (3) and 1,3,4-oxadiazole (4) through intermolecular cyclization. The synthesized compound 4 was subjected further to S-alkylation/aralkylation, using alkyl/aralkyl halides (5a-m) and S-substituted-1,3,4-oxadiazole derivatives were synthesized (6a-m). The structure elucidation of the synthesized molecules was processed through (1)H-NMR, IR and mass spectral data. The antibacterial activity showed these molecules moderately good inhibitors of gram-negative and gram-positive bacteria.


Assuntos
Antibacterianos/síntese química , Oxidiazóis/síntese química , Antibacterianos/farmacologia , Oxidiazóis/farmacologia , Relação Estrutura-Atividade
16.
Pak J Pharm Sci ; 27(6): 1739-45, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25362587

RESUMO

Sulfonamides are adherent to a biologically dynamic category of compounds and are under consideration of many organic synthetic researches to synthesize pharmacologically important compounds. In this demonstrated research work, a benignant series of chlorinated sulfonamides were synthesized and screened against different enzymes. These various chlorinated sulfonamides (3a-i) were set up by pairing of different substituted anilines (2a-i) with 4-chlorobenzenesulfonyl chloride (1) under basic pH in an aqueous media. The structures of the synthesized chlorinated sulfonamides were furnished by 1H-NMR, IR & EI-MS. The different enzymes used for the evaluation of bioactivity of all the synthesized compounds were urease, butyrylcholinesterase (BChE) and lipoxygenase (LOX). All the compounds exhibited good inhibitory activities against these enzymes but the strong activity was shown against BChE and hence can be employed for discovery of 'lead' compounds against Alzheimer's disease (AD).


Assuntos
Inibidores da Colinesterase/síntese química , Sulfonamidas/síntese química , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores de Lipoxigenase/síntese química , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Urease/antagonistas & inibidores
17.
Pak J Pharm Sci ; 27(2): 271-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24577914

RESUMO

Coumarins have much importance in dyes, drugs, perfumes and pesticides. In the demonstrated research work, a benignant series of chlorinated coumarins was synthesized and screened against different enzymes. First, 6-Chloro-7-hydroxy-4-methyl-2H-chromen-2-one (3) was geared up by the reaction of 4-chlororesorcinol (1) and ethyl acetoacetate (2) in the presence of concentrated H(2)SO(4). Second, various O-substituted derivatives of chlorinated coumarins, 5a-j, were set up by pairing different alkyl/aralkyl halides, 4a-j, with 3 in the presence of NaH in DMF as solvent. The structures of all the synthesized compounds were clarified through spectral analysis using EI-MS, IR and (1)H-NMR. The different enzymes used for the evaluation of bioactivity of all the synthesized compounds were acetyl cholinesterase (AChE), butyryl cholinesterase (BChE) and lipoxygenase (LOX). The most proficient activity was shown against both cholinesterase enzymes.


Assuntos
Cumarínicos/síntese química , Cumarínicos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Cromatografia em Camada Fina , Halogenação , Indicadores e Reagentes , Inibidores de Lipoxigenase/síntese química , Inibidores de Lipoxigenase/farmacologia , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
18.
Pak J Pharm Sci ; 27(3): 517-24, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24811811

RESUMO

A new series of N-aryl/aralkyl substitued-2"-[(phenylsulfonyl)(piperidin-1-yl)amino]acetamide (7a-k) was synthesized. These derivatives were geared up by the pairing of benzenesulfonyl chloride (4) with 1-aminopiperidine (5) under dynamic pH control in aqueous media to afford parent compound N-(Piperidin-1-yl) benzenesulfonamide (6), followed by the substitution at nitrogen atom with different electrophiles N-aryl/aralkyl-substituted-2-bromoacetamides (3a-k) in the presence of sodium hydride (NaH) and N,N-Dimethylformamide (DMF) to give a new series of N-substituted derivatives of acetamide (7a-k) bearing piperidine moiety. All the synthesized compounds were confirmed on the basis of IR, EIMS and (1)H-NMR spectral data. The synthesized compounds were evaluated against acetylcholinesterase and butyrylcholinesterase (AChE and BChE) respectively and lipoxygenase (LOX) enzymes. Almost all the synthesized compounds displayed promising activity but few of them remained inactive against lipoxygenase enzymes.


Assuntos
Acetamidas/síntese química , Inibidores da Colinesterase/síntese química , Inibidores de Lipoxigenase/síntese química , Acetamidas/farmacologia , Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores de Lipoxigenase/farmacologia , Relação Estrutura-Atividade
19.
PLoS One ; 19(3): e0299106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38457393

RESUMO

The primary objective of this research is to develop a mathematical model, analyze the dynamic occurrence of thermal shock and exploration of how thermal memory with moving line impact of heat transfer within biological tissues. An extended version of the Pennes equation as its foundational framework, a new fractional modelling approach called the Prabhakar fractional operator to investigate and a novel time-fractional interpretation of Fourier's law that incorporates its historical behaviour. This fractional operator has multi parameter generalized Mittag-Leffler kernel. The fractional formulation of heat flow, achieved through a generalized fractional operator with a non-singular type kernel, enables the representation of the finite propagation speed of heat waves. Furthermore, the dynamics of thermal source continually generates a linear thermal shock at predefined locations within the tissue. Introduced the appropriate set of variables to transform the governing equations into dimensionless form. Laplace transform (LT) is operated on the fractional system of equations and results are presented in series form and also expressed the solution in the form of special functions. The article derives analytical solutions for the heat transfer phenomena of both the generalized model, in the Laplace domain, and the ordinary model in the real domain, employing Laplace inverse transformation. The pertinent parameter's influence, such as α, ß, γ, a0, b0, to gain insights into the impact of the thermal memory parameter on heat transfer, is brought under consideration to reveal the interesting results with graphical representations of the findings.


Assuntos
Algoritmos , Temperatura Alta , Modelos Teóricos
20.
Chemosphere ; 349: 140729, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37989439

RESUMO

Respecting the basic need of clean and safe water on earth for every individual, it is necessary to take auspicious steps for waste-water treatment. Recently, metal-organic frameworks (MOFs) are considered as promising material because of their intrinsic features including the porosity and high surface area. Further, structural tunability of MOFs by following the principles of reticular chemistry, the MOFs can be functionalized for the high adsorption performance as well as adsorptive removal of target materials. However, there are still some major concerns associated with MOFs limiting their commercialization as promising adsorbents for waste-water treatment. The cost, toxicity and regenerability are the major issues to be addressed for MOFs to get insightful results. In this article, we have concise the current strategies to enhance the adsorption capacity of MOFs during the water-treatment for the removal of toxic dyes, pharmaceuticals, and heavy metals. Further, we have also discussed the role of metallic nodes, linkers and associated functional groups for effective removal of toxic water pollutants. In addition to conformist overview, we have critically analyzed the MOFs as adsorbents in terms of toxicity, cost and regenerability. These factors are utmost important to address before commercialization of MOFs as adsorbents for water-treatment. Finally, some future perspectives are discussed to give directions for potential research.


Assuntos
Estruturas Metalorgânicas , Metais Pesados , Poluentes da Água , Purificação da Água , Estruturas Metalorgânicas/química , Metais Pesados/química , Corantes , Purificação da Água/métodos , Adsorção
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