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1.
RSC Adv ; 14(22): 15455-15467, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38741952

RESUMEN

In this study, through the utilization of the sol-gel combustion tactic, gadolinium (Gd)-doped cerium oxide (CeO2), Ce1-xGdxO2 (x = 0.00, 0.10, 0.20 and 0.30 (GDC)) ceramics were attained. The synthesized GDC ceramics were investigated using X-ray diffraction (XRD) to scrutinize their crystal structures and phase clarities. The obtained GDC ceramics have a single-phase cubic structure and belong to the crystallographic space group fm3̄m (225). The measurement of the diffraction angle of each reflection and the subsequent smearing of the renowned Bragg's relation provided coarse d-interplanar spacings. The stacking fault (SF) values of pure and Gd-doped CeO2 ceramics were assessed. To muse the degree of preferred orientation (σ) of crystallites along a crystal plane (h k l), the texture coefficient (Ci) of each XRD peak of GDC ceramics is gauged. By determining the interplanar distance (dh k l), the Bravais theory sheds light on the material's development. By exploiting Miller indices for the prime (1 1 1) plane, the lattice constants of GDC ceramics and cell volumes were obtained. Multiple techniques were employed to ascertain the microstructural parameters of GDC ceramics. A pyrometer substantiated the density of GDC ceramics. The room temperature (RT) Fourier transform infrared (FTIR) spectra of both un-doped and Gd-doped CeO2 were obtained. The UV-vis-NIR spectrometer recorded the GDC ceramics' reflectance (R) spectra at RT. For both undoped and Gd-doped CeO2, the absorption coefficient (α) spectra showed two distinct peaks. The R-dependent refractive index (η) and the α-dependent extinction coefficient (k) were determined for all GDC samples. The optical band gap (Eg) was obtained by integrating the Tauc and Kubelka-Munk approaches for GDC ceramics. For each GDC sample, the imaginary (εi) and real (εr) dielectric constants, as well as the dissipation factor (tan δ), were determined local to the characteristic wavelength (λc). Calculations were made for the Urbach energy (EU) and Urbach absorption coefficient (α0) for GDC ceramics. The minimum and maximum values of optical (σo) and electrical (σe) conductivity for GDC ceramics were determined. The volume (VELF) and surface (SELF) energy loss functions, which depend on the constants εi and εr, were used to measure electrons' energy loss rates as they travel across the surface. Raman spectroscopy revealed various vibrational modes in GDC ceramics. Finally, the implications are discussed herein.

2.
ACS Appl Bio Mater ; 6(6): 2211-2225, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37289638

RESUMEN

The strategy of chemical coprecipitation is implemented to synthesize nanoparticles of pristine CuSe, 5 and 10% Ni-doped CuSe, and 5 and 10% Zn-doped CuSe. All of the nanoparticles are found to be near stoichiometric by the evaluation of X-ray energy using electron dispersion spectra, and the elemental mapping shows uniform distribution. By X-ray diffraction examination, all of the nanoparticles are identified as being single-phase and having a hexagonal lattice structure. Field emission microscopy with electrons in both scanning and transmission modes affirmed the spherical configuration of the nanoparticles. The crystalline nature of the nanoparticles is confirmed by the presence of spot patterns observed in the selected area electron diffraction patterns. The observed d value matches well with the d value of the CuSe hexagonal (102) plane. Findings from dynamic light scattering reveal the size distribution of nanoparticles. The nanoparticle's stability is investigated by ζ potential measurements. Pristine and Ni-doped CuSe nanoparticles exhibit ζ potential values in the preliminary stability band of ±10 to ±30 mV, while Zn-doped nanoparticles feature moderate stability levels of ±30 to ±40 mV. The potent antimicrobial effects of synthesized nanoparticles are studied against Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris, Enterobacter aerogenes, and Escherichia coli bacteria. The 2,2-diphenyl-1-picrylhydrazyl scavenging test is used to investigate the nanoparticle's antioxidant activities. The results showed the highest activity for control (Vitamin C) with an IC50 value of 43.6 µg/mL, while the lowest for Ni-doped CuSe nanoparticles with an IC50 value of 106.2 µg/mL. Brine shrimps are utilized for in vivo cytotoxicity evaluation of the synthesized nanoparticles, which demonstrates that 10% Ni- and 10% Zn-doped CuSe nanoparticles are more damaging on brine shrimp instead on other nanoparticles with a 100% mortality rate. The lung cancer cell line of human (A549) is used to investigate in vitro cytotoxicity. The results indicate that pristine CuSe nanoparticles are more effective in the context of cytotoxicity against the A549 cell lines, possessing an IC50 of 488 µg/mL. The particulars of the outcomes are explained in depth.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Humanos , Antioxidantes/farmacología , Antioxidantes/química , Nanopartículas del Metal/uso terapéutico , Nanopartículas del Metal/química , Antiinfecciosos/farmacología , Antiinfecciosos/metabolismo , Células A549 , Zinc/farmacología
3.
ACS Omega ; 6(40): 26533-26544, 2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34661008

RESUMEN

A simple hydrothermal route is employed to synthesize pure copper indium disulfide (CIS) and CIS nanoparticles (NPs) mediated by various natural plant extracts. The plant extracts used to mediate are Azadirachta indica (neem), Ocimum sanctum (basil), Cocos nucifera (coconut), Aloe vera (aloe), and Curcuma longa (turmeric). The tetragonal unit cell structure of as-synthesized NPs is confirmed by X-ray diffraction. The analysis by energy-dispersive X-rays shows that all the samples are near-stoichiometric. The morphologies of the NPs are confirmed by high-resolution scanning and transmission modes of electron microscopy. The thermal stability of the synthesized NPs is determined by thermogravimetric analysis. The optical energy band gap is determined from the absorption spectra using Tauc's equation. The antimicrobial activity analysis and the estimation of the minimum inhibitory concentration (MIC) value of the samples are performed for Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Enterobacter aerogenes, and Staphylococcus aureus pathogens. It shows that the aloe-mediated CIS NPs possess a broad inhibitory spectrum. The best inhibitory effect is observed against S. aureus, whereas the least effect was exhibited against P. vulgaris. The least MIC value is found for aloe-mediated CIS NPs (0.300 mg/mL) against S. aureus, P. aeruginosa, and E. aerogenes, along with basil-mediated NPs against E. coli. The antioxidant activity study showed that the IC50 value to inhibit the scavenging activity is maximum for the control (vitamin C) and minimum for pure CIS NPs. The in vivo cytotoxicity study using brine shrimp eggs shows that the pure CIS NPs are more lethal to brine shrimp than the natural extract-mediated CIS NPs. The in vitro cytotoxicity study using the human lung carcinoma cell line (A549) shows that the IC50 value of turmeric extract-mediated CIS NPs is minimum (15.62 ± 1.58 µg/mL). This observation reveals that turmeric extract-mediated CIS NPs are the most potent in terms of cytotoxicity toward the A549 cell line.

4.
Bioorg Med Chem Lett ; 29(11): 1423-1429, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30940396

RESUMEN

Indole- and azaindole-based glyoxylyl amide derivatives have been described as HIV-1 attachment inhibitors (AIs) that act by blocking the interaction between the viral gp120 coat protein and the human host cell CD4 receptor. As part of an effort to more deeply understand the role of the indole/azaindole heterocycle in the expression of antiviral activity, a survey of potential replacements was conducted using parallel synthesis methodology. The design and optimization was guided by a simple 2-dimensional overlay based on an overall planar topography between the indole/azaindole and C-7 substituents that had been deduced from structure-activity studies leading to the discovery of temsavir (3). 2-Substituted naphthalene- and quinoline-derived chemotypes emerged as the most interesting prototypes, with C-5 and C-6 substituents enhancing antiviral potency. Despite the fact that neither of these chemotypes incorporated a H-bond donor that has been shown to engage the side chain carboxylate of Asp113 in gp120, the antiviral potency of several analogues met or exceeded that of 3, demonstrating that engaging Asp113 is not a prerequisite for potent antiviral activity.


Asunto(s)
Fármacos Anti-VIH/farmacología , VIH-1/efectos de los fármacos , Indoles/farmacología , Acoplamiento Viral/efectos de los fármacos , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/química , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Humanos , Indoles/síntesis química , Indoles/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad
5.
Bioorg Med Chem Lett ; 28(21): 3463-3471, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30290989

RESUMEN

An unprecedented series of organometallic HCV (hepatitis C virus) NS5A (nonstructural 5A protein) replication complex inhibitors that incorporates a 1,1'-ferrocenediyl scaffold was explored. This scaffold introduces the elements of linear flexibility and non-planar topology that are unconventional for this class of inhibitors. Data from 2-D NMR spectroscopic analyses of these complexes in solution support an anti (unstacked) arrangement of the pharmacophoric groups. Several complexes demonstrate single-digit picomolar in vitro activity in an HCV genotype-1b replicon system. One complex to arise from this investigation (10a) exhibits exceptional picomolar activity against HCV genotype 1a and 1b replicons, low hepatocellular cytotoxicity, and good pharmacokinetic properties in rat.


Asunto(s)
Antivirales/farmacología , Bencimidazoles/farmacología , Compuestos Ferrosos/farmacología , Hepacivirus/efectos de los fármacos , Metalocenos/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Replicación Viral/efectos de los fármacos , Animales , Antivirales/síntesis química , Antivirales/química , Antivirales/farmacocinética , Bencimidazoles/síntesis química , Bencimidazoles/química , Bencimidazoles/farmacocinética , Línea Celular Tumoral , Compuestos Ferrosos/síntesis química , Compuestos Ferrosos/química , Compuestos Ferrosos/farmacocinética , Humanos , Macaca fascicularis , Masculino , Metalocenos/síntesis química , Metalocenos/química , Metalocenos/farmacocinética , Microsomas Hepáticos/metabolismo , Estructura Molecular , Ratas Sprague-Dawley , Relación Estructura-Actividad
6.
J Hand Surg Asian Pac Vol ; 22(3): 371-375, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28774234

RESUMEN

Carpometacarpal fracture dislocations of the hand are a relatively uncommon injury. The injury is difficult to diagnose because of the gross swelling of the hand. The diagnosis of this unusual form of injury requires a high index of suspicion, vigilant examination and high-quality radiography. This article reports a case of young male grieved with dislocation of all carpometacarpal (CMC) joints due to motor vehicle collision. Standard radiographs and CT scan revealed dorsal dislocations of second to fourth CMC joints, volar fracture dislocation of fifth carpometacarpal joint, fracture dislocation of CMC joint of thumb and dorsal dislocation of the trapezoid. Patient was treated with closed manipulation and percutaneous pinning with multiple K - wires. Follow up radiographs showed adequate reduction and fracture union. Intensive postoperative physiotherapy is vital for achieving a good outcome.


Asunto(s)
Articulaciones Carpometacarpianas/lesiones , Fractura-Luxación/diagnóstico por imagen , Fractura-Luxación/cirugía , Fijación Interna de Fracturas , Fracturas Múltiples/diagnóstico por imagen , Fracturas Múltiples/cirugía , Adulto , Hilos Ortopédicos , Humanos , Masculino , Radiografía , Tomografía Computarizada por Rayos X
7.
Appl Biochem Biotechnol ; 178(8): 1630-51, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26749293

RESUMEN

The present study describes grafting of zinc oxide (ZnO) nanoparticles with polyethyleneimine (PEI) followed by modification with glutraldehyde used as the bridge for binding the enzyme to support. The prepared nanocomposites were then characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy, utilized for synthesis of geranyl acetate in n-hexane. Among all the three prepared nanocomposites (ZnO + PEI, ZnO + PEI + SAA, ZnO + PEI + GLU), Candida rugosa lipase immobilized on ZnO-PEI-GLU was found to be best for higher ester synthesis. The operating conditions that maximized geranyl acetate resulted in the highest yield of 94 % in 6 h, molar ratio of 0.1:0.4 M (geraniol/vinyl acetate) in the presence of n-hexane as reaction medium. Various kinetic parameters such as V max, K i(G), K m(G), and K m(VA) were determined using nonlinear regression analysis for order bi-bi mechanism. The kinetic study showed that reaction followed order bi-bi mechanism with inhibition by geraniol. Activation energy (E a ) was found to be lower for immobilized lipase (12.31 kJ mol(-1)) than crude lipase (19.04 kJ mol(-1)) indicating better catalytic efficiency of immobilized lipase. Immobilized biocatalyst demonstrated 2.23-fold increased catalytic activity than crude lipase and recycled 20 times. The studies revealed in this work showed a promising perspective of using low-cost nanobiocatalysts to overcome the well-known drawbacks of the chemical-catalyzed route.


Asunto(s)
Acetatos/síntesis química , Biotransformación , Enzimas Inmovilizadas/química , Lipasa/química , Terpenos/síntesis química , Acetatos/química , Monoterpenos Acíclicos , Candida/enzimología , Catálisis , Enzimas/química , Cinética , Nanopartículas/química , Solventes/química , Terpenos/química , Óxido de Zinc/química
8.
J Indian Soc Periodontol ; 20(4): 460-463, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28298831

RESUMEN

The Whale's tail technique performed to obtain maximum interdental papilla fill in the anterior region after placement of bone grafts. This study aims to assess the clinical efficacy of this new technique. This report describes a series of three cases with a probing depth of 6-7 mm in the maxillary anterior teeth and their treatment with Whale's tail technique to obtain regeneration and maximum papilla preservation. The cases in this report showed a pocket depth reduction of 3-4mm and a clinical attachment gain of 3-4mm. The application of the "Whale's tail" flap leads to clinically significant improvement of hard and soft tissue conditions and allows regeneration of wide intrabony defects involving the maxillary anterior teeth with notable interdental diastemas, maintaining interproximal tissue to recreate a functional attachment with esthetic results.

9.
Antimicrob Agents Chemother ; 57(7): 3168-77, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23629709

RESUMEN

Treatment of hepatitis C patients with direct-acting antiviral drugs involves the combination of multiple small-molecule inhibitors of distinctive mechanisms of action. ACH-806 (or GS-9132) is a novel, small-molecule inhibitor specific for hepatitis C virus (HCV). It inhibits viral RNA replication in HCV replicon cells and was active in genotype 1 HCV-infected patients in a proof-of-concept clinical trial (1). Here, we describe a potential mechanism of action (MoA) wherein ACH-806 alters viral replication complex (RC) composition and function. We found that ACH-806 did not affect HCV polyprotein translation and processing, the early events of the formation of HCV RC. Instead, ACH-806 triggered the formation of a homodimeric form of NS4A with a size of 14 kDa (p14) both in replicon cells and in Huh-7 cells where NS4A was expressed alone. p14 production was negatively regulated by NS3, and its appearance in turn was associated with reductions in NS3 and, especially, NS4A content in RCs due to their accelerated degradation. A previously described resistance substitution near the N terminus of NS3, where NS3 interacts with NS4A, attenuated the reduction of NS3 and NS4A conferred by ACH-806 treatment. Taken together, we show that the compositional changes in viral RCs are associated with the antiviral activity of ACH-806. Small molecules, including ACH-806, with this novel MoA hold promise for further development and provide unique tools for clarifying the functions of NS4A in HCV replication.


Asunto(s)
Antivirales/farmacología , Proteínas Portadoras/antagonistas & inhibidores , Hepacivirus/efectos de los fármacos , Feniltiourea/análogos & derivados , Proteínas no Estructurales Virales/antagonistas & inhibidores , Animales , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Hepacivirus/fisiología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Feniltiourea/farmacología , ARN Viral/biosíntesis , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacos
10.
Antivir Ther ; 17(8): 1533-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22976492

RESUMEN

BACKGROUND: ACH-1625 is a linear peptidomimetic inhibitor that non-covalently binds to HCV NS3 protease with high potency and specificity. Short-term monotherapy of HCV genotype-1 infection with ACH-1625 was found to be safe and resulted in ≥3.3 log(10) IU/ml mean viral load reduction. These viral load decay data were analysed to compare HCV dynamics with prior reports and estimate the antiviral efficiency of ACH-1625. METHODS: Drug efficiency was estimated by analysing the viral decay following initiation of up to 5 days of monotherapy with ACH-1625 in 36 chronically infected HCV genotype-1 patients. During this monotherapy study, ACH-1625 was administered either twice-a-day for 4.5 days or once daily for 5 days at 5 different dose levels in 36 patients. RESULTS: A sharp viral decay during the first 48 h following the initiation of ACH-1625 treatment afforded high drug efficiency estimates (≥0.9934). In addition, an increase in the estimated drug efficiency was observed with increasing ACH-1625 dose. The observed anti-HCV response was fairly uniform in this proof-of-concept study across the population of 36 patients. CONCLUSIONS: Estimates of the treatment-independent viral kinetics parameters were consistent with prior reports and the estimated drug efficiency of ACH-1625 monotherapy was very high (≥0.9934) in fasted and fed states.


Asunto(s)
Antivirales/uso terapéutico , Inhibidores de la Proteasa del VIH/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Algoritmos , Antivirales/administración & dosificación , Antivirales/farmacocinética , Genotipo , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/farmacocinética , Hepacivirus/fisiología , Humanos , Cinética , Modelos Biológicos , Carga Viral
11.
ACS Med Chem Lett ; 3(3): 222-6, 2012 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-24900458

RESUMEN

A novel class of bicyclo[3.1.0]hexanylpiperazine neuropeptide Y (NPY) Y1 antagonists has been designed and synthesized. Scatchard binding analysis showed these compounds to be noncompetitive with [(125)I]PYY binding to the Y1 receptor. The most potent member, 1-((1α,3α,5α,6ß)-6-(3-ethoxyphenyl)-3-methylbicyclo[3.1.0]hexan-6-yl)-4-phenylpiperazine (2) had an IC50 = 62 nM and displayed excellent oral bioavailability in rat (% F po = 80), as well as good brain penetration (B/P ratio = 0.61). In a spontaneous nocturnal feeding study with male Sprague-Dawley rats, 2 significantly reduced food intake during a 12 h period.

12.
Antimicrob Agents Chemother ; 55(6): 2860-71, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21464250

RESUMEN

ACH-702, a novel isothiazoloquinolone (ITQ), was assessed for antibacterial activity against a panel of Gram-positive and Gram-negative clinical isolates and found to possess broad-spectrum activity, especially against antibiotic-resistant Gram-positive strains, including methicillin-resistant Staphylococcus aureus (MRSA). For Gram-negative bacteria, ACH-702 showed exceptional potency against Haemophilus influenzae, Moraxella catarrhalis, and a Neisseria sp. but was less active against members of the Enterobacteriaceae. Good antibacterial activity was also evident against several anaerobes as well as Legionella pneumophila and Mycoplasma pneumoniae. Excellent bactericidal activity was observed for ACH-702 against several bacterial pathogens in time-kill assays, and postantibiotic effects (PAEs) of >1 h were evident with both laboratory and clinical strains of staphylococci at 10 × MIC and similar in most cases to those observed for moxifloxacin at the same MIC multiple. In vivo efficacy was demonstrated against S. aureus with murine sepsis and thigh infection models, with decreases in the number of CFU/thigh equal to or greater than those observed after vancomycin treatment. Macromolecular synthesis assays showed specific dose-dependent inhibition of DNA replication in staphylococci, and biochemical analyses indicated potent dual inhibition of two essential DNA replication enzymes: DNA gyrase and topoisomerase IV. Additional biological data in support of an effective dual targeting mechanism of action include the following: low MIC values (≤0.25 µg/ml) against staphylococcal strains with single mutations in both gyrA and grlA (parC), retention of good antibacterial activity (MICs of ≤0.5 µg/ml) against staphylococcal strains with two mutations in both gyrA and grlA, and low frequencies for the selection of higher-level resistance (<10⁻¹°). These promising initial data support further study of isothiazoloquinolones as potential clinical candidates.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Quinolonas/farmacología , Tiazoles/farmacología , Inhibidores de Topoisomerasa II , Animales , Replicación del ADN/efectos de los fármacos , Topoisomerasa de ADN IV/antagonistas & inhibidores , Femenino , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Quinolonas/farmacocinética , Staphylococcus aureus/efectos de los fármacos , Tiazoles/farmacocinética
13.
J Med Chem ; 54(9): 3418-25, 2011 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-21443219

RESUMEN

We investigated compounds related to the previously reported antistaphyloccocal agent AVE6971 in an effort to attenuate inhibition of hERG potassium channel current that has been noted for this and related antibacterial drug classes. While most modifications of the original thiophene group compromised antibacterial activity, one selenophene analogue displayed (i) improved activity against the primary target enzyme DNA gyrase, (ii) similar activities against a panel of MRSA clinical isolates, and (iii) reduced hERG channel inhibition.


Asunto(s)
Antibacterianos/síntesis química , Compuestos de Organoselenio/síntesis química , Piperidinas/síntesis química , Quinolinas/síntesis química , Staphylococcus aureus/efectos de los fármacos , Inhibidores de Topoisomerasa II/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Línea Celular Tumoral , Topoisomerasa de ADN IV/antagonistas & inhibidores , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/enzimología , Compuestos de Organoselenio/química , Compuestos de Organoselenio/farmacología , Piperidinas/química , Piperidinas/farmacología , Quinolinas/química , Quinolinas/farmacología , Staphylococcus aureus/enzimología , Estereoisomerismo , Relación Estructura-Actividad , Tiofenos/síntesis química , Tiofenos/química , Tiofenos/farmacología , Inhibidores de Topoisomerasa II/química , Inhibidores de Topoisomerasa II/farmacología
14.
J Med Chem ; 54(9): 3268-82, 2011 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-21425851

RESUMEN

A series of 7-(3'-substituted)pyrrolidino-8-methoxyisothiazoloquinolone (ITQ) analogues were prepared, and their antibacterial potency against methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli were compared. Many of these analogues had MIC ≤ 0.25 µg/mL against quinolone-resistant MRSA strains. The stereochemical preference was explored for a series of 1''-methyl-3'-aminomethylpyrrolidine analogues. Antibacterial activity was generally more favorable with 3'-R, 1''-S configuration. Substitution on the 3'-aminomethyl nitrogen tended to decrease activity, while potency was maintained with disubstitution or aryl substitution at the 1''-carbon. The 7-[(R)-3-((S)-1-aminoethyl)pyrrolidin-1-yl] analogue (6a(R,S)) and the (R)-7-[3-(2-aminopropan-2-yl)pyrrolidin-1-yl] analogue (7a(R)) were found to be the ITQs with the most promising antibacterial profiles. The MICs of these select ITQs versus a panel of clinical MRSA strains were determined, and the ITQs were found to have 8- to 16-fold greater potency than linezolid. These analogues were also evaluated for inhibition of the target enzymes, topoisomerase IV and DNA gyrase, from both wild-type and multidrug resistant strains. The ITQs were up to >30 times more inhibitory against these targets than the fluoroquinolone moxifloxacin.


Asunto(s)
Antibacterianos/síntesis química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pirrolidinas/síntesis química , Quinolonas/síntesis química , Tiazoles/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Topoisomerasa de ADN IV/antagonistas & inhibidores , Farmacorresistencia Bacteriana Múltiple , Escherichia coli/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Pirrolidinas/química , Pirrolidinas/farmacología , Quinolonas/química , Quinolonas/farmacología , Estereoisomerismo , Relación Estructura-Actividad , Tiazoles/química , Tiazoles/farmacología , Inhibidores de Topoisomerasa II
15.
ACS Med Chem Lett ; 2(3): 224-9, 2011 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24900306

RESUMEN

The iminothiazolidinone BMS-858 (2) was identified as a specific inhibitor of HCV replication in a genotype 1b replicon assay via a high-throughput screening campaign. A more potent analogue, BMS-824 (18), was used in resistance mapping studies, which revealed that inhibitory activity was related to disrupting the function of the HCV nonstructural protein 5A. Despite the development of coherent and interpretable SAR, it was subsequently discovered that in DMSO 18 underwent an oxidation and structural rearrangement to afford the thiohydantoin 47, a compound with reduced HCV inhibitory activity. However, HPLC bioassay fractionation studies performed after incubation of 18 in assay media led to the identification of fractions containing a dimeric species 48 that exhibited potent antiviral activity. Excision of the key elements hypothesized to be responsible for antiviral activity based on SAR observations reduced 48 to a simplified, symmetrical, pharmacophore realized most effectively with the stilbene 55, a compound that demonstrated potent inhibition of HCV in a genotype 1b replicon with an EC50 = 86 pM.

16.
J Indian Med Assoc ; 108(6): 365, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21121387

RESUMEN

A review of 25 cases of heel pain treated conservatively with phonophoresis, using the anti-inflammatory gel containing a combination of flufenamic acid, salicylic acid and mucopolysaccharide polysulphate is being reported here. The purpose of the study was to assess the effectiveness of a noninvasive procedure called phonophoresis in treating hell pain. It involved usage of ultrasound waves to deliver anti-inflammatory drugs to the painful site. The heel pain subsided in all the cases and did not recur for a period of one year till last reviewed indicating the definite role of phonophoresis in heel pain.


Asunto(s)
Fascitis Plantar/tratamiento farmacológico , Talón , Fonoforesis/métodos , Antiinflamatorios/uso terapéutico , Combinación de Medicamentos , Femenino , Ácido Flufenámico/uso terapéutico , Geles , Glicosaminoglicanos/uso terapéutico , Humanos , Masculino , Ácido Salicílico/uso terapéutico , Resultado del Tratamiento
17.
J Virol ; 84(1): 482-91, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19812153

RESUMEN

Using a cell-based replicon screen, we identified a class of compounds with a thiazolidinone core structure as inhibitors of hepatitis C virus (HCV) replication. The concentration of one such compound, BMS-824, that resulted in a 50% inhibition of HCV replicon replication was approximately 5 nM, with a therapeutic index of >10,000. The compound showed good specificity for HCV, as it was not active against several other RNA and DNA viruses. Replicon cells resistant to BMS-824 were isolated, and mutations were identified. A combination of amino acid substitutions of leucine to valine at residue 31 (L31V) and glutamine to leucine at residue 54 (Q54L) in NS5A conferred resistance to this chemotype, as did a single substitution of tyrosine to histidine at amino acid 93 (Y93H) in NS5A. To further explore the region(s) of NS5A involved in inhibitor sensitivity, genotype-specific NS5A inhibitors were used to evaluate a series of genotype 1a/1b hybrid replicons. Our results showed that, consistent with resistance mapping, the inhibitor sensitivity domain also mapped to the N terminus of NS5A, but it could be distinguished from the key resistance sites. In addition, we demonstrated that NS5A inhibitors, as well as an active-site inhibitor that specifically binds NS3 protease, could block the hyperphosphorylation of NS5A, which is believed to play an essential role in the viral life cycle. Clinical proof of concept has recently been achieved with derivatives of these NS5A inhibitors, indicating that small molecules targeting a nontraditional viral protein like NS5A, without any known enzymatic activity, can also have profound antiviral effects on HCV-infected subjects.


Asunto(s)
Hepacivirus/efectos de los fármacos , Tiazolidinas/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Sustitución de Aminoácidos , Antivirales/química , Antivirales/farmacología , Dominio Catalítico , Línea Celular , Evaluación Preclínica de Medicamentos/métodos , Genotipo , Humanos , Fosforilación/efectos de los fármacos , Replicón/efectos de los fármacos , Tiazolidinas/uso terapéutico , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacos
18.
J Indian Med Assoc ; 107(3): 173, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19810388

RESUMEN

A case of iatrogenic hypercalcaemia in a 63-year-old female presenting with low back pain and tingling and numbness in both lower limbs off and on is presented here along with a brief discussion of literature. The purpose of this case reporting is to highlight how vitamins can be dangerous if prescribed inadvertently.


Asunto(s)
Calcitriol/efectos adversos , Calcio/efectos adversos , Hipercalcemia/inducido químicamente , Conservadores de la Densidad Ósea/efectos adversos , Conservadores de la Densidad Ósea/uso terapéutico , Calcitonina/uso terapéutico , Calcitriol/uso terapéutico , Calcio/farmacocinética , Calcio/uso terapéutico , Diuréticos/uso terapéutico , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Furosemida/uso terapéutico , Humanos , Hipercalcemia/sangre , Hipercalcemia/tratamiento farmacológico , Enfermedad Iatrogénica , Dolor de la Región Lumbar/tratamiento farmacológico , Persona de Mediana Edad
19.
Bioorg Med Chem Lett ; 19(17): 5136-9, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19632112

RESUMEN

1-(4-Benzoylpiperazin-1-yl)-2-(1H-indol-3-yl)ethane-1,2-dione (1a) has been characterized as an inhibitor of HIV-1 attachment that interferes with the interaction of viral gp120 with the host cell receptor CD4. In previous studies, the effect of indole substitution pattern on antiviral activity was probed. In this Letter, the effect of structural variation of the benzamide moiety is described, a study that reveals the potential or the phenyl moiety to be replaced by five-membered heterocyclic rings and a restricted tolerance for the introduction of substituents to the phenyl ring.


Asunto(s)
Fármacos Anti-VIH/química , Benzamidas/química , Proteína gp120 de Envoltorio del VIH/antagonistas & inhibidores , Inhibidores de Fusión de VIH/química , Indoles/química , Piperazinas/química , Acoplamiento Viral/efectos de los fármacos , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/farmacología , Benzamidas/síntesis química , Benzamidas/farmacología , Línea Celular , Proteína gp120 de Envoltorio del VIH/metabolismo , Inhibidores de Fusión de VIH/síntesis química , Inhibidores de Fusión de VIH/farmacología , Humanos , Indoles/síntesis química , Indoles/farmacología , Piperazinas/síntesis química , Piperazinas/farmacología , Relación Estructura-Actividad
20.
Bioorg Med Chem Lett ; 19(7): 1977-81, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19251416

RESUMEN

The effects of introducing simple halogen, alkyl, and alkoxy substituents to the 4, 5, 6 and 7 positions of 1-(4-benzoylpiperazin-1-yl)-2-(1H-indol-3-yl)ethane-1,2-dione, an inhibitor of the interaction between HIV gp120 and host cell CD4 receptors, on activity in an HIV entry assay was examined. Small substituents at C-4 generally resulted in increased potency whilst substitution at C-7 was readily tolerated and uniformly produced more potent HIV entry inhibitors. Substituents deployed at C-6 and, particularly, C-5 generally produced a modest to marked weakening of potency compared to the prototype. Small alkyl substituents at N-1 exerted minimal effect on activity whilst increasing the size of the alkyl moiety led to progressively reduced inhibitory properties. These studies establish a basic understanding of the indole element of the HIV attachment inhibitor pharmacophore.


Asunto(s)
Inhibidores de Fusión de VIH/química , Inhibidores de Fusión de VIH/farmacología , VIH-1/efectos de los fármacos , Indoles/farmacología , Acoplamiento Viral/efectos de los fármacos , Animales , Línea Celular , Perros , Proteína gp120 de Envoltorio del VIH/metabolismo , Infecciones por VIH/prevención & control , Humanos , Indoles/química , Indoles/farmacocinética , Ratas , Relación Estructura-Actividad
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