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1.
Heliyon ; 6(6): e04106, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32529077

RESUMO

Pyrroles are an exciting class of organic compounds with immense medicinal activities. This manuscript presents the structural and quantum mechanical studies of 1-(2-aminophenyl) pyrrole using X-Ray diffraction and various spectroscopic methods like Infra-Red, Raman, Ultra-violet and Fluorescence spectroscopy and its comparison with theoretical simulations. The single-crystal X-ray diffraction values and optimized geometry parameters also were within the agreeable range. A fully relaxed potential energy scan revealed the stability of the possible conformers of this molecule. We present the density functional theory results and assignment of the vibrational modes in the infrared spectrum. The experimental and scaled simulated vibrations matched when density functional theory simulations (B3LYP functional with 6-311++G∗∗). The electronic spectrum was simulated using time-dependent density functional theory with CAM-B3LYP functional in dimethylsulphoxide solvent. The fluorescence spectrum of the compound was studied at different excitation wavelengths in the dimethylsulphoxide solvent. The stability of the molecule by intramolecular electron transfer by hyperconjugation was studied with the natural bond orbital analysis. Frontier molecular orbitals and molecular electrostatic potentials of the compound gave an idea about the reactive behaviour of the compounds. Prediction of activity spectral studies followed by docking analysis indicated that the molecule is active against arylacetonitrilase inhibitor.

2.
Pak J Biol Sci ; 20(2): 82-91, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29022998

RESUMO

BACKGROUND: Caffeine, 1, 3, 7-trimethylxanthine is one of the xanthine derivatives that are for the most part utilized as a part of solutions as diuretics. The Cu (II) complexes have been synthesized from the N-heterocyclic carbene ligands. MATERIALS AND METHODS: The Cu (II) NHC complexes were characterized using analytical and spectral techniques. Antibacterial and antifungal activities of the Cu (II) NHC complexes were determined using the reported techniques. The SOD activity was assayed using nitrobluetetrazolium as O2 scavenger. RESULTS: The X-band ESR spectra of the copper complexes in DMSO solution at 300 and 77 K were recorded and their salient features are reported. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species, Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by serial dilution method. CONCLUSION: The Cu (II) complexes exhibit square planar geometry. A comparative study of inhibition values of the individual metals and their complexes indicate that the complexes exhibit higher antimicrobial activity than the individual metals. Superoxide dismutase and reducing power activities of the copper complexes have also been studied. Depending on the molecular structure, the Cu (II) NHC complex possess promising SOD mimetic activities. Further we are trying to explore more biological properties of Cu (II) NHC complexes in vitro and in vivo.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Cafeína/síntese química , Cafeína/farmacologia , Cobre/química , Cobre/farmacologia , Xantinas/síntese química , Xantinas/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Cafeína/análogos & derivados , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/farmacologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Mimetismo Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Superóxido Dismutase/química
3.
Indian J Sex Transm Dis AIDS ; 35(1): 43-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24958986

RESUMO

Cutaneous metastasis from an internal organ malignancy is rare and as, the presenting sign of malignancy is an uncommon phenomenon. Their presence, signals a poor prognosis. We report a case of 50-year-old female who was referred to sexually transmitted diseases - out patient department, with complaints of multiple genital ulcers to rule out sexually transmitted infections. After thorough evaluation, she was found to be a case of carcinoma cervix with metastatic squamous cell carcinomatous deposits on external genitalia. This case was unique because of relatively asymptomatic nature of internal malignancy and atypical presentation of carcinoma cervix as cutaneous metastasis.

4.
Microbiol Res ; 166(5): 419-29, 2011 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21237628

RESUMO

Cell wall bound calcium constitutes a significant fraction (25%) of total mycelia calcium in Neurospora crassa. Wall bound calcium increases as a function of growth and calcium concentration, while cell wall bound calcium decreases in Ca-free medium. Removal of wall bound calcium causes its rapid replacement from intracellular pool, inhibited by verapamil, nifedipine, concanamycin A, and wortmanin in a vacuolar mutant (Vma-5), but is unaffected by trifluoropyrazine, and calmidizoluim in a calcineurin mutant (Cnb-1) of N. crassa. Ca(2+) removal from surface with EGTA resulted in leakage of periplasmic enzymes invertase and alkaline phosphatase. Scanning and transmission electron microscopy revealed gross abnormalities represented by giant vacuoles. Toxic metal ions bound to wall fraction by displacing calcium. Our data underline the physiological importance of wall bound calcium in N. crassa.


Assuntos
Cálcio/metabolismo , Parede Celular/química , Parede Celular/fisiologia , Neurospora crassa/química , Neurospora crassa/fisiologia , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Homeostase , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Neurospora crassa/metabolismo , Neurospora crassa/ultraestrutura
5.
J Fluoresc ; 21(2): 563-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20931268

RESUMO

The new ligand 4-(isopropylbenzaldehyde)imidazo[4,5-f ][1,10]phenanthroline (ippip) and its complexes [Ru(phen)(2)(ippip)](2+)(1),[Co(phen)(2)(ippip)](3+)(2),[Ru(bpy)(2)(ippip)](2+)(3),[Co(bpy)(2)(ippip)](3+)(4)(bpy=2,2-bipyridine) and (phen=1,10-phenanthroline) were synthesized and characterized by ES(+)-MS, (1)H and (13)C NMR. The DNA binding properties of the four complexes were investigated by different spectrophotometric methods and viscosity measurements. The results suggest that complexes bind to calf thymus DNA (CT-DNA) through intercalation. When irradiated at 365 nm, the complexes promote the photocleavage of pBR322 DNA, and complex 1 cleaves DNA more effectively than 2, 3, 4 complexes under comparable experimental conditions. Furthermore, photocleavage studies reveal that singlet oxygen ((1)O(2)) plays a significant role in the photocleavage.


Assuntos
Cobalto/química , DNA/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Piridinas/química , Rutênio/química , Absorção , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Bovinos , Linhagem Celular Tumoral , DNA/química , Humanos , Desnaturação de Ácido Nucleico , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Processos Fotoquímicos , Espectrometria de Fluorescência , Estereoisomerismo , Especificidade por Substrato , Temperatura , Viscosidade
6.
J Fluoresc ; 21(3): 1155-64, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21181246

RESUMO

Three symmetric ligands 7-methyl dipyrido-[3,2-a;2',3'-c]phenazine (dppz-CH(3)), 7-nitro dipyrido-[3,2-a;2',3'-c]phenazine (dppz-NO(2)) and benzo[i]dipyrido-[3,2-a;2',3'-c]phenazine (dppn) and their ruthenium(II) complexes [Ru(en)(2)(L)][ClO(4)](2) (en= ethylenediamine), L= dppz-CH(3), dppz-NO(2) and dppn have been synthesized and characterized by IR, (1)H, (13)C NMR and Mass spectra. The interactions of these complexes with calf thymus DNA have been investigated by spectrophotometric, spectrofluorimetric, circular dichroism, viscosity and thermal denaturation studies. As the planar extension of the intercalative ligand increases, the interaction of the complex with DNA increases, indicating that the size and shape of the intercalalative ligand has a marked effect on the strength of interaction. The plot of log K versus log [Na(+)] yield a slope of -1.26, -1.53, -1.60 for the complexes 1, 2 and 3 respectively. These three complexes have been found to promote the cleavage of plasmid pBR 322 DNA upon irradiation.


Assuntos
Antibacterianos/síntese química , Medições Luminescentes , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , DNA/metabolismo , Dano ao DNA/efeitos dos fármacos , Etilenodiaminas/química , Ligantes , Fenazinas/química , Rutênio/química
7.
Pediatr Blood Cancer ; 52(7): 881-3, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19165887

RESUMO

We report a rare case of cellular fetal rhabdomyoma in a 9-year-old male, in the unusual location of right lower thigh. These tumors are more common in the head and neck region; and this case the second such case to be reported in the thigh. Fetal rhabdomyoma is a benign tumor of the skeletal muscle, showing varying degrees of skeletal muscle maturation. The present report discusses the histopathological features, the differential diagnosis and the importance of making the correct diagnosis for proper management of this rare entity.


Assuntos
Extremidade Inferior/patologia , Rabdomioma/patologia , Criança , Humanos , Extremidade Inferior/embriologia , Masculino , Rabdomioma/embriologia
8.
Biochem Biophys Res Commun ; 356(3): 622-8, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17374526

RESUMO

Efforts to clone amyloidogenic proteins in the cells often have resulted in cell death. We report successful cloning and expression of recombinant human islet amyloid polypeptide (hIAPP) in cultured mammalian cells. Amylin gets secreted, forms fibrils that are toxic to target cells like beta cells of rat and human. The study involves cloning of full-length amylin in fluorescent protein vector followed by transfection into mammalian cells. The transfected cells with recombinant human amylin, secrete the translated protein corresponding to 37-amino acid native mature IAPP. The mature IAPP secreted out of the cell is purified and characterized by MALDI-TOF/TOF-MS and Western blotting. Purified IAPP forms fibrils as seen by Thioflavin-T fluorescence and AFM, and these fibrils were cytotoxic towards pancreatic cell line RIN5mf cells.


Assuntos
Amiloide/genética , Amiloide/biossíntese , Animais , Benzotiazóis , Células CHO , Células COS , Sobrevivência Celular , Células Cultivadas , Chlorocebus aethiops , Clonagem Molecular , Cricetinae , Cricetulus , Escherichia coli/metabolismo , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Microscopia de Força Atômica , Ratos , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tiazóis , Transfecção
9.
Chem Biodivers ; 3(11): 1219-29, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17193235

RESUMO

A series of mixed-ligand ruthenium(II) complexes of the type [Ru(en)(2)bpy](2+) (bpy=2,2-bipyridine; 1), [Ru(en)(2)phen](2+) (phen=1,10-phenantroline; 2), [Ru(en)(2)IP](2+) (IP=imidazo[4,5-f][1,10]phenanthroline; 3), and [Ru(en)(2)PIP](2+) (PIP=2-phenylimidazo[4,5-f][1,10]phenanthroline; 4) have been isolated and characterized by UV/VIS, IR, and (1)H-NMR spectral methods. The binding of the complexes with calf thymus DNA has been investigated by absorption, emission spectroscopy, viscosity measurements, DNA melting, and DNA photo-cleavage. The spectroscopic studies together with viscosity measurements and DNA melting studies support that complexes 1 and 2 bind to CT DNA (=calf thymus DNA) by groove mode. Complex 2 binds more avidly to CT DNA than complex 1, complexes 3 and 4 bind to CT DNA by intercalation mode, 4 binds more avidly to CT DNA than 3. Noticeably, the four complexes have been found to be efficient photosensitisers for strand scissions in plasmid DNA.


Assuntos
DNA/química , Etilenodiaminas/química , Rutênio/química , Animais , Sítios de Ligação , Bovinos , Química/métodos , Íons , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Químicos , Conformação de Ácido Nucleico , Fármacos Fotossensibilizantes/farmacologia , Espectrofotometria Infravermelho/métodos , Espectrofotometria Ultravioleta/métodos , Timo/química
10.
Can J Microbiol ; 52(12): 1247-54, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17473894

RESUMO

A series of cobalt(III) mixed ligand complexes of type [Co(en)2L]+3, where L is bipyridine, 1,10-phenanthroline, imidazole, methylimidazole, ethyleimidazole, dimethylimidazole, urea, thiourea, acetamide, thioacetamide, semicarbazide, thiosemicarbazide, or pyrazole, have been isolated and characterized. The structural elucidation of these complexes has been explored by using absorption, infrared, and 1H NMR nuclear magnetic resonance spectral methods. The infrared spectral data of all these complexes exhibit a band at 1450/cm and 1560-1590/cm, which correspond to C=C and C=N, a band at 575/cm for Co-N (en), and a band at 480/cm for Co-L (ligand). All these complexes were found to be potent antimicrobial agents. The antibacterial activity was studied in detail in terms of zone inhibition, minimum bactericidal, and time period of lethal action. Among all, complexes bipyridine, 1,10-phenanthroline, dimethylimidazole, and pyrazole, possess the highest antibacterial activity. Antifungal activity was done by disc-diffusion assay and 50% inhibitory concentrations that possess high antifungal activity.


Assuntos
Anti-Infecciosos/farmacologia , Cobalto/farmacologia , Etilenodiaminas/farmacologia , Compostos Organometálicos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Antifúngicos/química , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Cobalto/química , Etilenodiaminas/química , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Compostos Organometálicos/química , Fatores de Tempo
11.
Can J Microbiol ; 51(12): 1021-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16462860

RESUMO

To establish the relevance of the cell wall in metal ion transport, cobalt uptake was examined in Neurospora crassa. Cobalt taken up was largely surface bound (>90%), resulting in a release of calcium and magnesium. Surface-bound cobalt could not enter intracellular locations upon further incubation of mycelia in a metal-free medium. Saturation of the surface with one metal augured subsequent dose-dependent entry of a different metal into intracellular locations. In comparison with the cobalt-resistant mutant, the cobalt-sensitive strain of N. crassa bound less cobalt on the surface but with significant intracellular accumulation. Our results demonstrate the importance of the cell wall in metal transport, toxicity, and resistance in fungi.


Assuntos
Neurospora crassa/metabolismo , Fracionamento Celular , Parede Celular/metabolismo , Cobalto/metabolismo , Transporte de Íons , Mutação , Neurospora crassa/genética , Espectrofotometria Atômica
13.
Biometals ; 16(4): 529-37, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12779238

RESUMO

A cobalt-resistant wall-less mutant (slime) of Neurospora crassa was obtained by repeated sub-culturing of the sensitive wall-less mutant (W-sl) on agar medium containing toxic concentrations of cobalt. Resistance was stable on culturing Cor-sl on cobalt-free medium up to 15 weekly subcultures. Cor-sl is 10-fold more resistant to cobalt when compared to W-sl. It is also cross-resistant to Cu (10-fold) and Ni (3-fold). Cobalt accumulated by Cor-sl during growth and in short-term uptake experiments was lower when compared to W-sl. Cells previously loaded with cobalt was released into medium in both mutants, while in case of Cor-sl most of cobalt taken up (> 80%), was released back into the medium when compared to W-sl. Metabolic inhibitor (Sodium azide) and magnesium ions inhibited cobalt uptake in both the mutants. Fractionation of cell-free extracts showed that most of the cobalt (70%) taken up by Cor-sl was bound to an inducible protein fraction which bound to DEAE-Cellulose, while in W-sl only 20% of cobalt was associated with this fraction. Subcellular localization of cobalt in W-sl indicated most of it to be cytoplasmic (70%) while nuclei and mitochondria had 10% and 5% respectively. In case of Cor-sl, mitochondrial cobalt accounted for only 2% while no significant differences were noted for other fractions. Our data implicate both transport block and intracellular sequestration of cobalt to play a major role in resistance.


Assuntos
Parede Celular/fisiologia , Cobalto/farmacologia , Farmacorresistência Fúngica , Mutação/genética , Neurospora crassa/efeitos dos fármacos , Azidas/farmacologia , Transporte Biológico/efeitos dos fármacos , Cinética , Magnésio/farmacologia , Neurospora crassa/citologia , Neurospora crassa/genética
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