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1.
RSC Adv ; 14(17): 11900-11907, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38623285

RESUMO

Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycles and high rates due to electrode degradations. In this prospective, an effective strategy is employed to develop advanced electrode materials for lithium-ion batteries (LIBs). In the present work, a mesoporous Co3O4@CdS hybrid sructure is developed and investigated as anode for LiBs. The hybrid structure owning porous nature and large specific surface area, provides an opportunity to boost the lithium storage capabilities of Co3O4 nanorods. The Co3O4@CdS electrode delivers an initial discharge capacity of 1292 mA h g-1 at 0.1C and a very stable reversible capacity of 760 mA h g-1 over 200 cycles with a capacity retention rate of 92.7%. In addition, the electrode exhibits excellent cyclic stability even after 800 cycles and good rate performance as compared to previously reported electrodes. Moreover, density functional theory (DFT) and electrochemical impedance spectroscopy (EIS) confirm the enhanced kinetics of the Co3O4@CdS electrode. The efficient performance of the electrode may be due to the increased surface reactivity, abundant active sites/interfaces for rapid Li+ ion diffusion and the synergy between Co3O4 and CdS NPs. This work demonstrates that Co3O4@CdS hybrid structures have great potential for high performance batteries.

2.
Future Med Chem ; 16(6): 497-511, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38372209

RESUMO

Background: Unsymmetrical thioureas 1-20 were synthesized and then characterized by various spectroscopy techniques such as UV, IR, fast atom bombardment (FAB)-MS, high-resolution FAB-MS, 1H-NMR and 13C-NMR. Methods: Synthetic compounds 1-20 were tested for their ability for antioxidant, lipoxygenase and xanthine oxidase activities. Results: Compounds 1, 2, 9, 12 and 15 exhibited strong antioxidant potential, whereas compounds 1-3, 9, 12, 15 and 19 showed good to moderate lipoxygenase activity. Ten compounds demonstrated moderate xanthine oxidase inhibition. Conclusion: Compound 15 displayed the highest potency among the series, exhibiting good antioxidant, lipoxygenase and xanthine oxidase activities. Theoretical calculations using density functional theory and molecular docking studies supported the experimental findings, indicating the potential of the synthesized compounds as potent antioxidants, lipoxygenases and xanthine oxidase agents.


Assuntos
Antioxidantes , Lipoxigenase , Antioxidantes/química , Simulação de Acoplamento Molecular , Xantina Oxidase/química , Xantina Oxidase/metabolismo , Inibidores Enzimáticos/química , Tioureia/farmacologia , Tioureia/química , Relação Estrutura-Atividade
3.
RSC Adv ; 14(1): 529-537, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38173575

RESUMO

To identify potential scaffolds to treat gastritis and oxidative stress, 2-aryl-1H-naphtho[2,3-d]imidazole derivatives (1-15) were synthesized. The synthesis was conveniently carried out by condensing 2,3-diaminonaphthalene with variously substituted aldehydes to yield 15 new 2-aryl-1H-naphtho[2,3-d]imidazole derivatives. Structures of all synthesized compounds were elucidated using MS and NMR spectroscopic techniques. Compounds containing an imidazole moiety have continued to spark interest in the field of medicinal chemistry due to their unique properties. In continuation of this statement, to further explore the biological potential of these types of compounds, newly synthesized imidazole derivatives were evaluated for their inhibitory potential against urease and antioxidant activities. Compounds 4 and 11 were identified as the most potent urease inhibitors in the series, with IC50 values of 34.2 ± 0.72 and 42.43 ± 0.65 µM, respectively. Compounds 1, 3, 6, 11, and 15, with EC50 values in the range of 37-75 µg ml-1, showed significant antioxidant activity. Molecular docking studies of the selected synthesized compounds 3, 4, 9, and 11 were also performed to determine their binding interaction with the jack bean urease. Through docking studies, it was revealed that all the compounds that showed good inhibitory potential against urease fit well within the protein's binding pocket. Furthermore, ADME analysis was carried out to explore the drug-likeness properties of the compounds. The findings of the present work revealed that compounds 4 and 11 could be better options to treat gastritis and associated oxidative stress.

4.
Environ Monit Assess ; 196(2): 197, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265542

RESUMO

Poultry products such as meat and eggs are rich sources of proteins, vitamins, and minerals. It is a good indicator of healthy food. Keeping in view, the present study is designed to evaluate the prevalence of toxic heavy metals (lead, nickel, cadmium, and chromium) in chicken eggs and feed. For this purpose, five samples of egg and feed were collected from five different commercial markets in Skardu City. Each sample was prepared using the wet digestion method and analyzed using a flame atomic absorption spectrophotometer. The results showed that lead, nickel, and chromium were present in varying amounts in the feed and egg, with nickel being the most concentrated metal, followed by lead and chromium in egg samples, while the feed samples showed the highest concentration of chromium followed by lead and nickel. However, concentrations of selected heavy metals except cadmium were all above the permissible limit of the World Health Organization. The self-organizing map-artificial neural network is employed for the identification of patterns of heavy metals in chicken feed and egg samples. The lower left neurons of the maps showed higher heavy metal concentrations found in samples taken from Bazar, whereas the rest of the samples showed varied concentrations. A comparison of feed and egg concentrations showed that nickel concentration was lower in feed samples than in egg samples. The lead concentration decreased in eggs except in the Krasmathang feed sample. Chromium concentration presented a negative correlation due to the extremely high concentration found in the Bazar feed sample.


Assuntos
Galinhas , Chumbo , Animais , Níquel , Cádmio , Monitoramento Ambiental , Intoxicação por Metais Pesados , Redes Neurais de Computação , Cromo
5.
Nanoscale Adv ; 5(24): 6925-6934, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38059043

RESUMO

This article explores the properties of heat and mass transport for MHD Casson nanofluid flow between two horizontal plates by considering the Darcy-Forchheimer medium. The effects of a uniform inclined magnetic field are discussed numerically. A Darcy-Forchheimer medium is considered in the x-direction between two plates. The features of Brownian diffusive motion, porosity, friction, viscous dissipation, chemical reaction, and thermophoresis are also considered. The governing equations of the model are a system of partial differential equations. This system is converted into non-linear ordinary differential equations using suitable similarity functions. The numerical shooting technique is used to solve the attained boundary value problem. This numerical technique is endowed with the Runge-Kutta order four method and the Newton method. Graphs and tables depict different significant effects. It is observed that the effect of a magnetic field is inversely related to the fluid flow. Moreover, the porosity factor (λ) and the magnetic inclination (γ) are inversely related to the surface drag force (Cf) and the Nusselt number (Nu).

6.
Food Addit Contam Part B Surveill ; 16(1): 69-76, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35909386

RESUMO

Sudan dyes were investigated in branded and non-branded spices, commonly available in the markets of Karachi, Pakistan. High performance liquid chromatography (HPLC) with a variable wavelength detector (VWD) was applied to determine Sudan dyes I-IV. The non-branded samples had higher concentrations of Sudan dyes than the maximum limits of 0.1 mg/kg. The highest concentration of Sudan dye (I) was found in turmeric powder (8460 mg/kg) and the lowest concentration (1.50 mg/kg) of Sudan (IV) in Chaat Masala. This indicates that the use of non-branded spices is not safe, whereas no Sudan dye was found in the branded spice samples. Further studies regarding the higher carcinogenic risk posed by Sudan dye adulterated spices in Pakistan is strongly advised.


Assuntos
Corantes , Especiarias , Corantes/análise , Especiarias/análise , Paquistão , Contaminação de Alimentos/análise , Cromatografia Líquida de Alta Pressão/métodos , Compostos Azo/análise
7.
Nanotechnology ; 33(37)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35749132

RESUMO

The detection of cholesterol is very crucial in clinical diagnosis for rapid and accurate monitoring of multiple disease-biomarkers. There is a great need for construction of a highly reliable and stable electrocatalyst for the efficient detection of cholesterol. In this work, mesoporous NiCo2S4nanoflakes of enhanced electrochemical properties are prepared through a facile hydrothermal approach. The developed nanoflakes modified nickel foam electrode exhibits outstanding electrocatalytic properties for the detection of cholesterol with high selectivity. The electrode displays excellent sensitivity of 8623.6µA mM-1cm-2, in the wide linear range from 0.01 to 0.25 mM with a low detection limit of 0.01µM. In addition, NiCo2S4structure reveals good thermal stability and reproducibility over a period of 8 weeks. Moreover, the nanoflakes show good response for detection of cholesterol in real samples. Our results demonstrate the potential use of NiCo2S4as a catalyst for the development of cost-effective electrochemical sensors for medical and industrial applications.


Assuntos
Técnicas Eletroquímicas , Níquel , Colesterol , Técnicas Eletroquímicas/métodos , Eletrodos , Níquel/química , Reprodutibilidade dos Testes
8.
Nanotechnology ; 33(2)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34598172

RESUMO

The development of a reliable non-enzymatic multi-analyte biosensor is remained a great challenge for biomedical and industrial applications. In this prospective, rationally designed electrode materials having voltage switchable electrocatalytic properties are highly promising. Here, we report vanadium doped ZnO engineered nanostructures (Zn1-xVxO where 0 ≤ x ≤ 0.1) which exhibit voltage switchable electrocatalytic properties for accurate measurements of glucose and hydrogen peroxide. Microstructures and chemical analysis show that the oxygen vacancies in the material can be tuned by controlling the stoichiometric ratios which play key role for voltage dependent measurements of different analytes. The developed Zn1-xVxO nanostructures exhibit outstanding sensing ability for binary analytes with a high selectivity, low detection limit, thermal stability and long-term stability. The Zn0.9V0.1O/glassy carbon (GC) electrode shows 3-fold increase in reproducible sensitivity for both glucose (655.24µA mM-1cm-2) and H2O2(13309.37µA mM-1cm-2) as compared to the pristine ZnO/GC electrode. Moreover, the electrode also shows good response for human blood serum and commercially available samples. The results demonstrate that defect engineering is a promising route for the development of cost-effective non-enzymatic multi-analyte sensors for practical applications.

9.
Cureus ; 13(7): e16435, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34414051

RESUMO

Adaptive coping strategies are used to reduce stress in patients undergoing cardiac surgery. These strategies have a major role in physical health, psychological health, quality of life and also affect an individual's response to the disease. The current study was conducted to comprehend the impact of coping strategies on the quality of life of patients suffering from cardiac disease. A purposive convenient sampling method was used to collect data from different hospitals in South Punjab. We applied Carver's Brief Coping Orientation to Problem Experienced (Brief COPE) inventory and the WHO quality of life scale. A cross-sectional research design was proposed for the study. The findings of the study showed that coping strategies and quality of life are associated with each other, and the use of emotion-focused and problem-focused coping strategies have a significant impact on patients experiencing cardiac surgery. Demographic details of patients also revealed the differences in both variables. Implications and future recommendations have also been discussed.

10.
Bioorg Chem ; 108: 104638, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33508679

RESUMO

A series of nineteen (1-19) indole-based-thiadiazole derivatives were synthesized, characterized by 1HNMR, 13C NMR, MS, and screened for α-glucosidase inhibition. All analogs showed varied α-glucosidase inhibitory potential with IC50 value ranged between 0.95 ± 0.05 to 13.60 ± 0.30 µM, when compared with the standard acarbose (IC50 = 1.70 ± 0.10). Analogs 17, 2, 1, 9, 7, 3, 15, 10, 16, and 14 with IC50 values 0.95 ± 0.05, 1.10 ± 0.10, 1.30 ± 0.10, 1.60 ± 0.10, 2.30 ± 0.10, 2.30 ± 0.10, 2.80 ± 0.10, 4.10 ± 0.20 and 4.80 ± 0.20 µM respectively showed highest α-glucosidase inhibition. All other analogs also exhibit excellent inhibitory potential. Structure activity relationships have been established for all compounds primarily based on substitution pattern on the phenyl ring. Through molecular docking study, binding interactions of the most active compounds were confirmed. We further studied the kinetics study of analogs 1, 2, 9 and 17 and found that they are Non-competitive inhibitors.


Assuntos
Inibidores de Glicosídeo Hidrolases/farmacologia , Indóis/farmacologia , Simulação de Acoplamento Molecular , Tiadiazóis/farmacologia , alfa-Glucosidases/metabolismo , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Indóis/química , Estrutura Molecular , Saccharomyces cerevisiae/enzimologia , Relação Estrutura-Atividade , Tiadiazóis/síntese química , Tiadiazóis/química
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 247: 119064, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091739

RESUMO

Surface adsorption of a dipeptide L-alanyl-L-tryptophan (Ala-Trp) on gold nanoparticles reduced by citrate (CT) and borohydride (BH) ions was investigated by a surface-enhanced Raman scattering (SERS) technique. Two distinct SERS spectra of Ala-Trp depending on the types of gold nanoparticles were observed, and the vibrational assignments were based on the density functional theory simulations and the previous SERS results of Trp. Ala-Trp mainly adsorbs through the amine group on CT gold nanoparticles with a perpendicular orientation of the indole ring to the surface. In contrast, the adsorption occurs via the π electrons of the indole ring on the BH gold surfaces while maintaining a flat geometry of the indole ring to the surface. The amide I band of Ala-Trp was observed only with the CT gold colloids in acidic and neutral conditions where partial surface adsorption via the amide group is expected.


Assuntos
Ouro , Nanopartículas Metálicas , Análise Espectral Raman , Adsorção , Dipeptídeos , Propriedades de Superfície , Triptofano
12.
Cureus ; 12(10): e11105, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33240701

RESUMO

Objective To observe spirometry and its correlation with postoperative pulmonary complications in cardiac surgery patients. Study design Prospective observational study Place and duration of the study Chaudhary Pervaiz Elahi Institute of Cardiology (CPEIC) Multan, from January 1, 2017, to June 30, 2020 Methodology Written informed consent was taken from 357 patients. Spirometry was performed in all the patients using the conventional method. Baseline data, including gender, age, body mass index (BMI), living area, smoking history, known lung illness, six-minute walk distance, predicted forced vital capacity (FVC) %, predicted forced expiratory volume in one second (FEV1) %, and type of the procedure such as aortic valve replacement (AVR), coronary artery bypass grafting (CABG), double-valve replacement (DVR), and mitral valve replacement (MVR) were documented for all the patients. Outcome data included postoperative ICU length of stay (LOS), respiratory failure, respiratory infection, atelectasis, and mortality. Results The most common procedure was CABG and MVR proceeded by n=254 (71.1%) and n=83 (23.2%) patients, respectively. Postoperative complications, such as respiratory failure, respiratory infection, and atelectasis, was noted in n=29 (8.1%), n=28 (7.8 %), and n=127 (35.6 %) patients, respectively, while n=5 (1.4%) patients died. Conclusion Deranged pulmonary function tests (PFTs) are associated with poor prognosis following elective cardiac surgery in terms of postoperative pulmonary complications such as pulmonary infection, respiratory failure, and atelectasis. There is a significant difference in percentage predicted of FVC and FEV1 in patients who developed atelectasis and respiratory tract infection.

13.
Cureus ; 12(2): e6851, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32181086

RESUMO

Objective To compare the effect of incentive spirometry with Acapella (Smiths Medical Inc, Carlsbad, California) in physiotherapy after coronary artery bypass surgery. Methods A randomized controlled trial comparing incentive spirometry with Acapella was conducted in the intensive care unit of Chaudhary Pervaiz Elahi Institute of Cardiology (CPEIC) Multan. The study began from December 2017 to August 2019 after getting approval from the ethical committee of the hospital. Informed written consent was taken from all 270 patients who were included in the study. Patients who underwent coronary artery bypass graft (CABG) were divided into two groups by the lottery method. The primary end-point of the study was to check the blood gases on Day 3 after the procedure at room air and compare it with the baseline and with blood gases immediately after the procedure. SPSS 23 (IBM Corp., Armonk, NY) was used to analyze the data of this study. For qualitative variables in data such as gender, place of living, patients with any comorbidities, and education status were statistically analyzed in percentage and frequencies. For numerical variables, such as age, body mass index, blood gases values, distance covered in a six-minute walk test, and spirometry values were analyzed and statistically measured as mean and standard deviation. A P-value of less than .05 was considered significant. Results The mean partial pressure of oxygen (PaO2) of incentive spirometry was 58.1±2.31 and 67.2±3.24 after extubation and after three days, respectively. While the PaO2 of Acapella was 56.3±3.43 and 66.4±3.54 after extubation and after three days, respectively. The mean PCO2 of incentive spirometry was 41.4±3.26 and 36.1±2.11 after extubation and after three days, respectively. While the partial pressure of carbon dioxide (PCO2) of Acapella was 39.4±2.55 and 37.5±3.58 after extubation and after three days, respectively. The differences were statistically significant at p-value ≤0.05. Conclusion It was concluded that both Acapella and incentive spirometry treatment after coronary artery bypass graft improved blood gases.

14.
Chem Commun (Camb) ; 56(15): 2336-2339, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31990284

RESUMO

Vibrational modes and tip enhanced Raman spectroscopy (TERS) of a new carbon allotrope, cyclo[18]carbon (C18), were studied by density functional theory. A silver cluster tip was used to probe the interaction with C18, which is dependent on the distance and the atomically resolved positions. The TERS images show the position of the C[triple bond, length as m-dash]C bonds, as observed in a recent experimental report.

15.
Nat Prod Res ; 34(16): 2315-2318, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30587037

RESUMO

The present work deals with the biological and phytochemical studies on Capparis decidua (Forssk) Edgew from Cholistan desert of Pakistan. Aerial and floral parts of C. decidua were collected and dried under shade. Powdered materials of each part of C. decidua were extracted with methanol separately, followed by phytochemical studies. Hexane fraction of aerial parts of the C. decidua obtained after solvent-solvent extraction was purified through repeated column chromatography by increasing order of polarity. Four compounds were purified and identified as simiarenol (1), lupeol (2), taraxerol (3) and ß-sitosterol (4). Simiarenol and lupeol were isolated for the first time from genus Capparis. The structures of these compounds were established by comparing the spectroscopic data (1H NMR, 13C NMR, IR, UV & Mass spectrometry) reported in literature. The structure of 1 was further confirmed by XRD analysis. Anti-bacterial activities of crude methanolic extracts were determined against 13 bacterial strains (MIC 250-1000 µg/mL). α-Glucosidase and urease inhibitory activities of pure compounds were also determined. Compounds 1, 2 and 4 showed α-glucosidase inhibition with IC50 at 96.12 ± 0.12, 65.28 ± 0.13 and 128.14 ± 0.17 µM, respectively.


Assuntos
Capparis/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Clima Desértico , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Estrutura Molecular , Paquistão , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Sitosteroides/química , Sitosteroides/isolamento & purificação
16.
Med Chem ; 16(6): 826-840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31195949

RESUMO

BACKGROUND: Results of our previous studies on antiglycation activity, and the noncytotoxicity of 2-mercapto benzothiazoles, encouraged us to further widen our investigation towards the identification of leads against diabetes mellitus. METHODS: 33 derivatives of 2-mercapto benzothiazoles 1-33 were evaluated for in vitro α- glucosidase inhibitory activity. Mode of inhibition was deduced by kinetic studies. To predict the interactions of 2-mercapto benzothiazole derivatives 1-33 with the binding pocket of α-glucosidase enzyme, molecular docking studies were performed on the selected inhibitors. RESULTS: Compounds 2-4, 6-7, 9-26, 28 and 30 showed many folds potent α-glucosidase inhibitory activity in the range of IC50 = 31.21-208.63 µM, as compared to the standard drug acarbose (IC50 = 875.75 ± 2.08 µM). It was important to note that except derivative 28, all other derivatives were also found previously to have antiglycating potential in the range of IC50 = 187.12-707.21 µM. CONCLUSION: A number of compounds were identified as dual nature as antiglycating agent and α- glucosidase inhibitors. These compounds may serve as potential lead candidates for the management of diabetes mellitus.


Assuntos
Benzotiazóis/química , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Cinética , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Saccharomyces cerevisiae/enzimologia , Relação Estrutura-Atividade , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
17.
J Ayub Med Coll Abbottabad ; 31(3): 359-363, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31535506

RESUMO

BACKGROUND: Irreversible hydrocolloid impression materials have been a staple in dentistry and useful for the fabrication of dental prosthesis. Gagging is most commonly experienced during maxillary impression making, which may affect the clinical management of the patient. Different techniques have been described to alleviate this problem. One of them is mixing lignocaine local anesthetic solution in irreversible hydrocolloid impression material before making the impression. The objective of this study was to evaluate the effect of lignocaine addition in irreversible hydrocolloid impression on the properties of irreversible hydrocolloid impression materials. METHODS: Irreversible hydrocolloid was mixed with water (Control group) or water and adrenalin (Lidocaine hydrochloride) (Experimental group). Compressive strength, tear strength and setting time were measured according to ISO1567 and ANSI/ADA specifications 18. The structural analysis of both groups was also evaluated by Fourier Transform Infrared Spectroscopy (FTIR). RESULTS: In the experimental group, insignificant decrease was observed in compressive and tear strength of irreversible hydrocolloid (p>0.05). There was significant (p<0.05) increase in setting time of irreversible hydrocolloid impression material. FTIR analysis indicated no change in chemistry of irreversible hydrocolloid before and after setting. CONCLUSIONS: Addition of lignocaine in irreversible hydrocolloid impression material may result in control of gag reflex without affecting its mechanical and chemical properties.


Assuntos
Anestésicos Locais/química , Coloides/química , Materiais para Moldagem Odontológica/química , Lidocaína/química , Humanos , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Bioorg Chem ; 79: 34-45, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29723741

RESUMO

Nicotinic and isonicotinic thiosemicarbazide or hydrazine carbothioamides 3-27 were synthesized and the structures of synthetic compounds were elucidated by various spectroscopic techniques such as EI-MS, 1H-, and 13C NMR. Synthetic derivatives were evaluated for their urease inhibitory activity which revealed that except few all derivatives demonstrated excellent inhibition in the range of IC50 values of 1.21-51.42 µM as compared to the standard thiourea (IC50 = 21.25 ±â€¯0.13 µM). Among the twenty-five synthetic derivatives nineteen 1-5, 7, 8, 10, 12, 14-18, 20-22, 24-27 were found to be more active showing IC50 values between 1.13 and 19.74 µM showing superior activity than the standard. Limited structure-activity relationship demonstrated that the positions of substituent as well as position of nitrogen in pyridine ring are very important for inhibitory activity of this class of compound. To verify these interpretations, in silico study was also performed. A good correlation was obtained between the biological evaluation of active compounds and docking study.


Assuntos
Inibidores Enzimáticos/química , Ácidos Isonicotínicos/química , Ácidos Nicotínicos/química , Tiossemicarbazonas/química , Canavalia/enzimologia , Domínio Catalítico , Inibidores Enzimáticos/síntese química , Ácidos Isonicotínicos/síntese química , Simulação de Acoplamento Molecular , Estrutura Molecular , Ácidos Nicotínicos/síntese química , Relação Estrutura-Atividade , Tiossemicarbazonas/síntese química , Urease/química
19.
Med Chem ; 14(1): 86-101, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28641525

RESUMO

BACKGROUND: Despite the availability of a variety of antibacterial agents, re-emergence of pathogenic bacteria is still a serious medical concern. So, identification of new, safer, and selective antibacterial agents is the key interest in the medicinal chemistry research. METHOD: To explore the antimicrobial activity of coumarin-3-carboxamides for a range of bacterial and fungal strains, twenty eight derivatives were synthesized by the reaction of coumarin-3-carboxylic acid with a variety of aniline derivatives in the presence of 1,1'-carbonyldiimidazole (CDI). All compounds were structurally characterized by different spectroscopic techniques EI-MS, HREI-MS, 1H-NMR, 13C-NMR, and evaluated for antimicrobial activities (antibacterial and antifungal). RESULTS: A number of compounds showed good to weak antibacterial activity against various strains of Gram-positive and Gram-negative bacteria. Amongst them, compound 28 displayed noticeable inhibition against five strains of Gram-positive (Bacillus subtilis, Corynebacterium xerosis, Staphylococcus aureus, Streptococcus faecalis, and MRSA) and four strains of Gram-negative bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogene, and Shigella dysenteria). However, none of the compounds showed antifungal activity against tested fungi. MIC values were determined for most of the active compounds 2, 15, and 28 against particular bacterial cultures. In silico studies were performed on the most active compound 28 in order to specify and verify the target for antibacterial activity of synthetic coumarin-3-carboxamide derivatives. The cytotoxicity of these compounds on mammalian cells is unknown yet but we are planning to carry out research on the cytotoxic aspect of these compounds in future. CONCLUSION: The newly identified compounds may serve as lead molecules for the future research regarding the identification of new antibacterial agents.


Assuntos
Amidas/farmacologia , Antibacterianos/farmacologia , Cumarínicos/farmacologia , Imidazóis/química , Amidas/síntese química , Amidas/química , Antibacterianos/síntese química , Antibacterianos/química , Cumarínicos/síntese química , Cumarínicos/química , Relação Dose-Resposta a Droga , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
20.
J Hered ; 108(6): 597-607, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28498961

RESUMO

The snow leopard, Panthera uncia, is an elusive high-altitude specialist that inhabits vast, inaccessible habitat across Asia. We conducted the first range-wide genetic assessment of snow leopards based on noninvasive scat surveys. Thirty-three microsatellites were genotyped and a total of 683 bp of mitochondrial DNA sequenced in 70 individuals. Snow leopards exhibited low genetic diversity at microsatellites (AN = 5.8, HO = 0.433, HE = 0.568), virtually no mtDNA variation, and underwent a bottleneck in the Holocene (∼8000 years ago) coinciding with increased temperatures, precipitation, and upward treeline shift in the Tibetan Plateau. Multiple analyses supported 3 primary genetic clusters: (1) Northern (the Altai region), (2) Central (core Himalaya and Tibetan Plateau), and (3) Western (Tian Shan, Pamir, trans-Himalaya regions). Accordingly, we recognize 3 subspecies, Panthera uncia irbis (Northern group), Panthera uncia uncia (Western group), and Panthera uncia uncioides (Central group) based upon genetic distinctness, low levels of admixture, unambiguous population assignment, and geographic separation. The patterns of variation were consistent with desert-basin "barrier effects" of the Gobi isolating the northern subspecies (Mongolia), and the trans-Himalaya dividing the central (Qinghai, Tibet, Bhutan, and Nepal) and western subspecies (India, Pakistan, Tajikistan, and Kyrgyzstan). Hierarchical Bayesian clustering analysis revealed additional subdivision into a minimum of 6 proposed management units: western Mongolia, southern Mongolia, Tian Shan, Pamir-Himalaya, Tibet-Himalaya, and Qinghai, with spatial autocorrelation suggesting potential connectivity by dispersing individuals up to ∼400 km. We provide a foundation for global conservation of snow leopard subspecies, and set the stage for in-depth landscape genetics and genomic studies.


Assuntos
Especiação Genética , Variação Genética , Genética Populacional , Panthera/genética , Animais , Ásia , Teorema de Bayes , Análise por Conglomerados , DNA Mitocondrial/genética , Repetições de Microssatélites , Panthera/classificação , Filogeografia , Análise de Sequência de DNA
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