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1.
Pak J Pharm Sci ; 35(4(Special)): 1251-1260, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36218104

RESUMO

Meloxicam (MEL) is an oxicam derivative with low water solubility that is useful in the treatment of colorectal cancer (CRC) as a COX-2 inhibitor. MEL-loaded HPMC micro particles were fabricated using an oil-in-oil (o/o) emulsion solvent evaporation (ESE) method. FTIR, XRD, particle size analysis, DSC, SEM and in vitro dissolution investigation were utilized to evaluate the produced micro particles physiochemically. Finally, rabbits were used as animal models in an in vivo pharmacokinetic study to assess the MEL concentration in the plasma of rabbits. Pure MEL, F1 and F2 were given to rabbits by a single dose for in vivo pharmacokinetic investigations. The XRD and DSC results confirmed the transformation of MEL from its crystalline nature to the amorphous state in micro particles. The formulations F1 and F2 particle sizes were determined 92.43µm and 163.26µm, respectively. The prepared micro particles had a smooth, non-porous and spherical surface. In comparison to the pure drug (22.4%), the F1 and F2 cumulative drug release (%) was 86.19% and 79.57%, respectively. Pure MEL, F1 and F2 have estimated Cmax values of 7.21, 25.41 and 22.38µg/mL, respectively. MEL had a half-life of 19.98 hours, which rose to 22.19 hours and 24.75 hours for F1 and F2, respectively. MEL, F1 and F2 had AUC0-α values of 116.034, 445.95 and 462.72µg/mL*h, respectively. Considering these aspects, MEL-loaded HPMC micro particles may have the potential to better the delivery and control the release of drug that is not easily dissolved in water which could lead to improved therapeutic efficacy and limited side effects.


Assuntos
Inibidores de Ciclo-Oxigenase 2 , Água , Animais , Emulsões , Derivados da Hipromelose/química , Meloxicam , Metilcelulose , Tamanho da Partícula , Coelhos , Solubilidade , Solventes
2.
PLoS One ; 17(4): e0267306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35468155

RESUMO

The study aimed to fabricate and evaluate Meloxicam (MLX) loaded Hydroxypropyl Methylcellulose (HPMC) microparticles for colon targeting because MLX is a potent analgesic used in the treatment of pain and inflammation associated with colorectal cancer (CRC). Nevertheless, its efficiency is limited by poor solubility and gastrointestinal tracts (GIT) associated side effects. Seventeen formulations of MLX loaded HPMC microparticles were fabricated by the oil-in-oil (O/O)/ emulsion solvent evaporation (ESE) technique. A 3-factor, 3-level Box Behnken (BBD) statistical design was used to estimate the combined effects of the independent variables on the dependent variables (responses), such as the percent yield (R1), the entrapment efficiency (EE) (R2), mean particle size (R3) and in vitro percentage of cumulative drug release (R4). For physicochemical characterization FTIR, XRD, DSC, and SEM analyses were performed. Biocompatibility and non-toxicity were confirmed by in-vivo acute oral toxicity determination. The percentage yield and EE were 65.75-90.71%, and 70.62-88.37%, respectively. However, the mean particle size was 62.89-284.55 µm, and the in vitro cumulative drug release percentage was 74.25-92.64% for 24 hours. FTIR analysis showed that the composition of the particles was completely compatible, while XRD analysis confirmed the crystalline nature of the pure drug and its transition into an amorphous state after formulation. DSC analysis revealed the thermal stability of the formulations. The SEM analysis showed dense spherical particles. The toxicity study in albino rabbits showed no toxicity and was found biocompatible. The histopathological evaluation showed no signs of altered patterns. Results of this study highlighted a standard colonic drug delivery system with the ability to improve patient adherence and reduce GIT drug-associated side effects in CRC treatment.


Assuntos
Colo , Sistemas de Liberação de Medicamentos , Animais , Sistemas de Liberação de Medicamentos/métodos , Humanos , Derivados da Hipromelose/química , Meloxicam , Coelhos , Solubilidade
3.
Pak J Pharm Sci ; 33(6(Supplementary)): 2767-2772, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33879435

RESUMO

Bovine serum albumin (BSA) is usually employed as a model protein because of being homologous with human serum albumin. Cysteine-34 of BSA has been oxidised with Ellman's reagent to produce BSA labelled with an Ellman's moiety (BSA-SE). The BSA-SE was then reacted with glutathione, N-acetylcysteine and D-penicillamine (D-pen). The two were able to release the Ellman's moiety bound at cysteine-34 while D-pen did not. Albumin labeled using Ellman's reagent was used to demonstrate the cleavage of a protein mixed disulphide. The kinetics of thiol disulfide interchange reactions involving formation of a chromophoric thiolate were determined by UV-visible spectroscopy. The reaction of thiolates with excess Ellman's reagent is used for quantitative estimation of thiol by measuring the absorption at λ, 412 nm. The disulfide exchange reactions occurring at Cys-34 of BSA was determined and the reduction of oxidized Cys-34 was studied in order to understand the reverse reaction. Spectroscopic evidence suggested that glutathione and N-acetylcysteine remove the label and produce BSA in a disulfide form. In contrast, D-pen reaction returned BSA to its thiolate form via mediation. It was observed that thio-disulfide exchange occurred at cysteine-34 labelled with Ellman's moiety. The implications to the redox status of plasma are discussed.


Assuntos
Dissulfetos/química , Ácido Ditionitrobenzoico/química , Soroalbumina Bovina/química , Compostos de Sulfidrila/química
4.
Pak J Pharm Sci ; 32(4): 1563-1570, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31608875

RESUMO

Herbal remedies like the Thymus serpyllum L. is useful in traditional medicine for the treatment of many diseases especially congestion, and bronchitis. The purpose of this study was to formulate a micro-emulsion, a gel and an ointment containing the plant hydro distilled thymus oil extracted from Thymus serpyllum L. collected from Ziarat, Balochistan. The prepared formulations were subjected to in-vitro and ex vivo study release, High performance Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC), to justify their suitability for topical use. The in-vitro and ex-Vivo release was studied using Franz Cells and using two different kinds of membrane synthetic dialysis cellulose membrane and natural rabbit skin and the amount of drug released was determined by HPLC at λ 274nm. The three formulations result obtained through dialysis cellulose membrane showed the faster release than the natural rabbit skin. However, the micro-emulsion, gel formulation showed the same release except ointment. The release from the above mentioned formulation can be arranged in the following descending order. micro-emulsion > Gel > Ointment. The best fit of release kinetics was achieved by Krosmeyer- Peppas, the TLC and HPLC identifies the Thymol, isolation and quantification of the marker. This study demonstrates that it is necessary to assess the impact of release and permeability pattern of different formulations. In vitro and ex-vivo diffusion cell experiments can be utilized to develop formulations of traditional medicines identifies.


Assuntos
Óleos de Plantas/administração & dosagem , Óleos de Plantas/farmacologia , Pele/efeitos dos fármacos , Thymus (Planta)/química , Administração Tópica , Animais , Celulose , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Diálise/instrumentação , Diálise/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Liberação Controlada de Fármacos , Emulsões/química , Emulsões/farmacocinética , Géis/química , Géis/farmacocinética , Masculino , Membranas Artificiais , Permeabilidade , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Coelhos , Timol/análise , Timol/farmacocinética
5.
Pak J Pharm Sci ; 31(4(Supplementary)): 1463-1467, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30058536

RESUMO

Thallium has been shown to significantly influence various tissues of living organisms; Exposure to Thallium can disturb mitochondrial function, degenerate neurons, and interfere with the function of critical metabolic enzymes and co-enzymes. Glutathione (GSH) an essential biomarker is considered a key factor in harnessing the thallium toxicity. In the present study the interaction of Thallium (Thallium Chloride) and glutathione was investigated spectro-photo-metrically in aqueous media. The renowned Elman's experimental protocol was followed at a wavelength of 412nm for Glutathione quantification in each sample. The pH of each sample was maintained at 7.6 using Phosphate buffer during the entire course of the experiment. A concentration as well as time dependent depletion of glutathione after exposure to various concentration of Thallium metal was observed, revealing chemical interaction between the metal and glutathione. The exact mechanism of interaction of Thallium and glutathione is still to be investigated. However, this piece of research suggests that a decrease in the concentration of Glutathione may be due to Thallium-GSH abduct or oxidize glutathione (GSSG) formation. This study was performed in-vitro as a model of in vivo.


Assuntos
Glutationa/análise , Tálio/análise , Tálio/farmacologia , Água/análise , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Espectrofotometria Ultravioleta , Tálio/metabolismo , Água/metabolismo
6.
Pak J Pharm Sci ; 31(2(Suppl.)): 727-731, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29625947

RESUMO

Glutathione is an essential antioxidant of living organism that provides a primary protection against metals toxicity. A significant amount of glutathione is present in blood erythrocytes, plasma and liver hepatocytes to protect them from oxidative damage from both external and internal oxidants. Metalo-element palladium has numerous pharmacological, clinical and toxicological compensations, like palladium is used as anti-viral, anti-bacterial, neuro-protective and anti-tumor agent. However studies have also indicated some mild to serious toxic effects of palladium metallo-elements. In the presence study the interaction of palladium inorganic salt and organic complex with glutathione (GSH) content of liver homogenate was examined spectro-photometrically. 20% (w/v) liver homogenate was prepared of the collected liver of rabbit in 5% TCA (tri-chloro-acetic acid) solution and 1mm EDTA, using a potter-eveljhem homogenizer with motor driven Teflon pestle. The GSH content quantification was carried out by Elman's method. Our finding showed that there was a depletion of GSH content by both palladium inorganic salts and organic complexes, concentrations wise as well as with time elapse as level of GSH content decrease from (43.6% to 72.62%) with Palladium Nitrate and from (24.09 to 59.5%) with Bis-benzonitrile Palladium II Chloride as compared to control, and further dropped with time incubation from 0-90 minutes from (49.7 to 87.1%), with Palladium Nitrate and from (29.3% to 67.6%) respectively. The result showed that the effect of both inorganic salt of palladium was more enhanced as compare to its organic complex. It was suggested from our finding that the depletion in the glutathione content of liver homogenate may be due to oxidation of glutathione or due to glutathione metal abduct formation by both inorganic salt and organic complex of palladium. This study in situ is a model of in vivo.


Assuntos
Glutationa/metabolismo , Fígado/metabolismo , Compostos Organometálicos/toxicidade , Paládio/toxicidade , Animais , Coelhos
7.
Pak J Pharm Sci ; 31(1): 213-219, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29348106

RESUMO

The metalloelement Palladium has a number of potential Pharmaco-clinical advantages. Palladium compounds have antiviral, antibacterial, neuroprotective and antitumor properties. However studies have also indicated some mild to serious toxic effects of Palladium metalloelements. Biothiols are important antioxidants that provide protection against metals toxicity. The interaction of metalloelements with biothiols can provide valuable information about the level of toxicity of the metalloelements and about the protective role of biothiols thereof. In this piece of work the effect of salt and complexes of Palladium on the status of different thiols (GSH, NAC, and D-Pen) in aqueous medium, were examined, The thiol quantification was carried out using Elman's method through UV-visible spectrophotometry and 1H- NMR. Results of the study performed in aqueous medium showed that level of different thiols depleted after the addition of the inorganic salts and organic complexes of Palladium. The mechanism of interaction of Palladium with thiols was examined using H-NMR. The results indicate that the depletion in the level of thiols may be due to 1:1 or 1:2 conjugation of Palladium with thiols. These conjugation reactions further suggest that the Palladium have xenobiotic nature causing oxidative stress and thiols play their role in detoxification and biotransformation of these metalloelements.


Assuntos
Acetilcisteína/química , Glutationa/química , Paládio/química , Penicilamina/química , Vanádio/química , Oxirredução , Paládio/toxicidade , Soluções , Vanádio/toxicidade
8.
Pak J Pharm Sci ; 30(6(Supplementary)): 2405-2410, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29188777

RESUMO

Thiol groups are extensively present across biological systems being found in range of small molecules (e.g. Glutathione, Homo-cysteine) and proteins (e.g. albumin, haemo-globin). Albumin is considered to be a major thiol containing protein present in circulating Plasma. Albumin contains a single thiolate group located at cysteine-34(cys-34) at its active site. Albumin also binds a wide variety of metals and metals complexes at various sites around the protein. Usually heavy metals are preferentially attached with the thiol group of albumin. The binding of heavy metals at cys-34 provides a mechanism by which the residence time of potentially toxic species in the body can be increased. In this research we have assessed the oxidative modification of and metal binding capacity of cys-34 with heavy metals Palladium and Vanadium to investigate the ease with which it is possible to effect disulfide-thiol exchange at this sites/or remove a metal bound at this position. Both the metals were treated with albumin and then the albumin metals (Pd and V) complexes were treated with small thoil molecules like Glutathione, Cysteine and D-Penicillamine. Our finding showed that the albumin thiol group retained the metals with itself by forming some strong bonding with the Thiols group, it is concluded from this finding that if by chance both the metals enter the living system; strongly disturb the chemistry and physiological function of this bio-molecule.


Assuntos
Acetilcisteína/metabolismo , Quelantes/metabolismo , Complexos de Coordenação/metabolismo , Glutationa/metabolismo , Paládio/metabolismo , Penicilamina/metabolismo , Soroalbumina Bovina/metabolismo , Compostos de Sulfidrila/metabolismo , Vanádio/metabolismo , Sítios de Ligação , Oxirredução , Ligação Proteica
9.
Mol Pharm ; 14(11): 4019-4031, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-29047275

RESUMO

Clofazimine (CFZ) is highly active against mycobacterium, including resistant Mycobacterium tuberculosis, but its therapeutic efficacy via the oral route is limited by severe adverse effects, poor aqueous solubility, and slow onset of action. Pulmonary delivery of CFZ is an attractive alternative to target mycobacterium-harboring alveolar macrophages. This study explores the use of air jet milling to develop a respirable, cost-effective CFZ formulation. Jet milled CFZ was readily dispersed from an off-the-shelf dry powder inhaler without the need for additional excipients or carrier particles. Additionally, milled CFZ was internalized by J774.A1 alveolar macrophages within 8 h, with evidence of intracellular biotransformation of the CFZ crystals and macrophage sequestration by 24 h. Less macrophage toxicity was noted in comparison to solubilized drug. Compared to macrophage uptake rate, dissolution of milled CFZ was limited, thereby potentially reducing systemic absorption and subsequent side effects. These results suggest that jet milling is an effective manufacturing method in the development of a CFZ formulation for pulmonary delivery and alveolar macrophage targeting.


Assuntos
Antituberculosos/química , Clofazimina/química , Excipientes/química , Antituberculosos/farmacologia , Clofazimina/farmacologia , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Tuberculose/metabolismo
10.
Pak J Pharm Sci ; 29(2): 381-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27087067

RESUMO

Investigation of toxicological effect of various metals is the field of interest for toxicological scientists since four to five decades and especially the toxicological effect of those drugs containing metals and there use is common because there is no other choice except to use these metal containing drugs. Inorganic as well as organic salts of lithium are commonly used in prophylaxis and treatments of many psychiatric disorders. The aim of the present study was to see the difference between the effect of organic and inorganic salt of lithium commonly used in psychiatric disorders on the GSH of human blood plasma. It is the scientific fact that ionic dissociation of organic and inorganic salts of any metal is always quite different hence to prove this fact, the effect of lithium citrate (organic salt of lithium) and lithium carbonate (inorganic salt of lithium) was investigated on human blood plasma GSH to find the difference between the effect of two. Ellman's method was used for the quantification of glutathione contents in plasma. It was found that lithium citrate decrease plasma GSH contents less than lithium carbonate indicating that organic salts of lithium are safe than inorganic salts of lithium when are used in psychiatric disorders. Further to analyze the effect of organic and inorganic salt of lithium on blood plasma GSH with the increase in incubation time was also evaluated and was found that both concentration and time dependent effect of organic salt of lithium shows that this salt has decreased plasma GSH contents of human blood less than inorganic salt of lithium either by promoting oxidation of GSH into GSSG or by lithium glutathione complex formation. These results suggest the physicians that the use of organic lithium salts is much safer than inorganic salts of lithium in terms of depletion of blood plasma GSH contents.


Assuntos
Citratos/sangue , Glutationa/sangue , Carbonato de Lítio/sangue , Psicotrópicos/sangue , Biomarcadores/sangue , Citratos/toxicidade , Relação Dose-Resposta a Droga , Dissulfeto de Glutationa/sangue , Humanos , Carbonato de Lítio/toxicidade , Psicotrópicos/toxicidade , Medição de Risco , Fatores de Tempo
11.
Pak J Pharm Sci ; 29(1): 89-95, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26826820

RESUMO

Toxicities of heavy metals is a burning issue and a topic of interest among the toxicologists throughout the world. Metals are always in use of man since long but in recent years the use of cadmium has increased in the form of various cadmium compounds such as cadmium compounds as stabilizers in plastic pipe industries and in the preparations of different alloys etc. Cadmium is even used in phosphate fertilizers and thus comes directly or indirectly in contact with human eatables like crops, vegetables and fruits. Once it is absorbed it affects almost all the organs and systems of human body especially blood components and kidneys. Always the chemical reactions of different chemicals are dependent on some influential factors, among these factors the effect of pH and temperature of the media in which these chemicals interact with each other are very much important. Keeping in view this fact we have evaluated the effect of cadmium nitrate tetra hydrate on GSH of human plasma and cytosolic fraction. Estimation of thiol was done by Ellman's modified method and was found that the interaction of cadmium nitrate tetra hydrate and GSH of these blood components was more at a pH and temperature, which were near to physiological pH and temperature of human body. This fact was proved as the estimated thiol concentration left after the interaction of cadmium nitrate tetra hydrate and thiol of these blood components was minimum at pH and temperature near to human blood pH and temperature. We concluded that the possible reason for depletion of GSH of these blood components was conversion of GSH into Cd(SG) (2) and/or GSSG formation.


Assuntos
Cádmio/toxicidade , Citosol/metabolismo , Glutationa/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Temperatura
12.
Pak J Pharm Sci ; 28(6): 2075-81, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26639500

RESUMO

Cadmium intake is associated with oxidative stress that causes depletion of intracellular as well as extra cellular reduced glutathione. There is strong evidence indicating that reactive oxygen species and reactive nitrogen species generated in the presence of cadmium could be responsible for its toxic effects in many cells and tissues. Depletion of reduced glutathione in various cells, especially in T and B-lymphocytes, causes extreme damage to the antioxidant defense system of body. The aim of this research work was to investigate the metabolic changes that occur in T and B lymphocytes after their incubation with organ cadmium diacetate by using Ellman's spectrophotometric method of thiol quantification. The results of the present study indicate that cadmium depleted T and B lymphocytes GSH to a harmful extent. It is proposed that this depletion is due to the bivalent cadmium glutathione complex formation, oxidation of reduced glutathione (GSH) to its oxidized form, or both.


Assuntos
Acetatos/toxicidade , Linfócitos B/efeitos dos fármacos , Cádmio/toxicidade , Glutationa/metabolismo , Compostos Organometálicos/toxicidade , Linfócitos T/efeitos dos fármacos , Linfócitos B/metabolismo , Relação Dose-Resposta a Droga , Humanos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Linfócitos T/metabolismo , Fatores de Tempo
13.
Pak J Pharm Sci ; 28(4 Suppl): 1523-32, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26431664

RESUMO

IL-28Rα and IL10Rß collectively construct a fully functional hetero-dimeric receptor for type III interferons (IFNs). IL-28Rα is the private chain for type III IFNs since their involvement in any other pathway has not been reported yet and they are highly expressed in response to certain viral attack or cancers. IL-28Rα is specific in their expression pattern and it expresses within few cell types only. The regulatory mechanisms governing the expression of IL-28Rα at the molecular level are not completely known yet and need to be scrutinized at primary levels. In the present study, various in-silico techniques were applied and it was observed that AP1-2, STAT 1-6, P-53, LyF-1 (lymphoid transcription factor), c-Jun, PU.1, CREB (cAMP response element-binding), PLAG (pleotropic adenoma gene), MYOD (myoblast determination protein 1), NOFL and KLFS as transcription factors that are selected with preference. Interestingly AP-2, c-Jun, LyF-1, STAT, NF-Y and P53 have also been reported in literature recently as some of the key regulatory elements as well. Based on the fact that interlinking between different interferon stimulation genes (ISGs) is also not very clear and induction of one type of interferon can affect the efficacy of the other, we found that IFN-λ4 induction can increase the expression of IL-28Rα, similar to IFN-λ3 but contrary to type I IFNs, which has either no effect on the expression of IL-28Rα or can down regulate its expression at higher concentrations (data not published).


Assuntos
Regulação da Expressão Gênica , Polimorfismo de Nucleotídeo Único , Receptores de Citocinas/genética , Sítios de Ligação , Simulação por Computador , Humanos
14.
Pak J Pharm Sci ; 28(2): 457-64, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25730780

RESUMO

Arsenic is a major threat to large part of the population due to its carcinogenic nature. The toxicity of Arsenic varies with its chemical form and oxidation states. Glutathione (GSH), a major intra-cellular tripeptide plays a major role in arsenic detoxification. The present study was designed to provide insight into the extent of changes in GSH level by inorganic arsenic in the form of Arsenic trioxide (ATO) and organic arsenic in the form of nitro benzene arsenic acid (NBA). Lymphocytes (T.cells and B.cells) were investigated for determination of change in GSH metabolic status caused by arsenic. The depletion of GSH level positively correlated with increasing arsenic concentration and time of incubation. The decline in GSH level was consistent with increasing pH and physiological temperature. Our findings show that changes in GSH status produced by Arsenic could be due to adduct (As-(SG)3) formation. This change in GSH metabolic status provides information regarding mechanism of toxicity of inorganic and organic arsenicals. These findings are important for the rational design of antidote for the prevention of arsenic induced toxicity.


Assuntos
Arseniatos/toxicidade , Intoxicação por Arsênico/metabolismo , Linfócitos B/efeitos dos fármacos , Glutationa/metabolismo , Óxidos/toxicidade , Linfócitos T/efeitos dos fármacos , Trióxido de Arsênio , Arsenicais , Linfócitos B/metabolismo , Humanos , Linfócitos T/metabolismo
15.
Pak J Pharm Sci ; 27(6): 1789-98, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25362603

RESUMO

Diclofenac sodium (DCL-Na) conventional oral tablets exhibit serious side effects when given for a longer period leading to noncompliance. Controlled release matrix tablets of diclofenac sodium were formulated using simple blending (F-1), solvent evaporation (F-2) and co-precipitation techniques (F-3). Ethocel® Standard 7 FP Premium Polymer (15%) was used as a release controlling agent. Drug release study was conducted in 7.4 pH phosphate buffer solutions as dissolution medium in vitro. Pharmacokinetic parameters were evaluated using albino rabbits. Solvent evaporation technique was found to be the best release controlling technique thereby prolonging the release rate up to 24 hours. Accelerated stability studies of the optimized test formulation (F-2) did not show any significant change (p<0.05) in the physicochemical characteristics and release rate when stored for six months. A simple and rapid method was developed for DCL-Na active moiety using HPLC-UV at 276nm. The optimized test tablets (F-2) significantly (p<0.05) exhibited peaks plasma concentration (cmax=237.66±1.98) and extended the peak time (tmax=4.63±0.24). Good in-vitro in vivo correlation was found (R(2)=0.9883) against drug absorption and drug release. The study showed that once-daily controlled release matrix tablets of DCL-Na were successfully developed using Ethocel® Standard 7 FP Premium.


Assuntos
Celulose/análogos & derivados , Diclofenaco/química , Polímeros/química , Animais , Celulose/química , Química Farmacêutica , Preparações de Ação Retardada , Diclofenaco/administração & dosagem , Éteres , Masculino , Polímeros/farmacocinética , Coelhos , Solubilidade , Comprimidos
16.
Pak J Pharm Sci ; 26(6): 1181-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24191324

RESUMO

Interferon Lambda (IFN-λ) is a type III interferon which belongs to a novel family of cytokines and possesses antiviral and antitumor properties. It is unique in its own class of cytokines; because of the specificity towards its heterodimer receptors and its structural similarities with cytokines of other classes. This renders IFN-λ a better choice for the treatment against many diseases including viral hepatitis and human coronavirus (HCoV-EMC). The present study describes a computational approach known as relative synonymous codon usage (RSCU); used to enhance the expression of IFN-λ protein in a eukaryotic expression system. Manually designed and commercially synthesized IFN-λ gene was cloned into pET-22b expression plasmid under the control of inducible T7-lac promoter. Maximum levels of IFN-λ expression was observed with 0.4 mM IPTG in transformed E. coli incubated for 4 hours in LB medium. Higher concentrations of IPTG had no or negative effect on the expression of IFN-λ. This synthetically over expressed IFN-λ can be tested as a targeted treatment option for viral hepatitis after purification.


Assuntos
Códon , Escherichia coli/genética , Genes Sintéticos , Interferons/genética , Clonagem Molecular , Expressão Gênica
17.
Pak J Pharm Sci ; 26(3): 617-22, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23625439

RESUMO

Achieving a desirable percutaneous absorption of drug molecule is a major concern in formulating dermal and transdermal products. The use of penetration enhancers could provide a successful mean for this purpose. The aim of this study was to develop Clotrimazole gel and to evaluate the effect of almond oil and tween 80 (in different concentrations), on the permeation of drug through rabbit skin in vitro. In order to investigate the effect of penetration enhancers used in this study on the permeation of Clotrimazole through sections of excised rabbit skin, Franz diffusion cell was employed. Sample solution was withdrawn at specific time interval up to 24 h. Significant difference in permeation among the eight formulations was seen in the study. The permeation profile of various formulations also showed that the added enhancers in individual batches affected the permeation of the drug. Drug permeation increased with increased concentration of Tween 80 and decreased concentration of almond oil. Furthermore, almond oil combined with tween 80 showed synergistic effect. The clotrimazole gels were successfully formulated and could be beneficial for topical use.


Assuntos
Clotrimazol/administração & dosagem , Clotrimazol/química , Géis/química , Óleos de Plantas/química , Polissorbatos/administração & dosagem , Polissorbatos/química , Administração Tópica , Animais , Química Farmacêutica/métodos , Géis/administração & dosagem , Permeabilidade , Coelhos , Absorção Cutânea
18.
Pak J Pharm Sci ; 26(1): 131-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23261738

RESUMO

This piece of research work present the toxicological impact of varied concentrations of palladium nitrate [Pd (NO3)2] by changing the chemical status of glutathione and the way how glutathione plays its role in detoxification and conjugation processes of [Pd (NO(3))(2))] in whole blood components (plasma and cytosolic fraction). The impact of different concentration of [Pd (NO3)2] on reduced glutathione level in whole blood component (plasma and cytosolic fraction) were measured spectrophotometrically following Standard Ellman's method. Compared with control sample, significant decrease in the GSH content in whole blood components (plasma and cytosolic fraction) was obtained with various concentrations (100µM-1000µM) of palladium nitrate. Depleted GSH level was more pronounced with time incubation period (0-90) minutes. These finding shows that changes in the GSH status produced by palladium nitrate could either be due to palladium nitrate and glutathione( Pd-SG) complex formation or by conversion of reduce glutathione (2GSH + Pd(+2) - GSSG). This change in the GSH metabolic status provides information regarding the mechanism of palladium, in blood components.


Assuntos
Glutationa/sangue , Paládio/toxicidade , Citosol/metabolismo , Relação Dose-Resposta a Droga , Humanos , Paládio/sangue , Espectrofotometria , Fatores de Tempo
19.
Pak J Pharm Sci ; 25(4): 883-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23010010

RESUMO

Barium has important role in the field of medical sciences, but it has been found in various studies that barium can cause numerous toxic effects. Studies have proven the strong affinity of the metalloelements for the sulfhydryl group (SH), present in reduced glutathione (GSH) and other biological molecules. In this context, the study about the possible interaction of BaCl(2) with glutathione in whole blood components was of interest, as an indication about the extent of barium toxicity and the role of glutathione in the conjugation and detoxification of the metalloelement barium. The concentration dependent and time dependent effect of BaCl(2) on the level of GSH in plasma and cytosolic fraction in whole blood was investigated, following Ellman's method. It was found that BaCl(2) causes a decrease in the GSH level, which is more pronounced with increasing concentration of BaCl(2) and with time incubation as well. The observed effect GSH concentration may be presumably due to production of oxidized glutathione (GSSG) or then due to barium-glutathione (GS-Ba-SG) conjugate formation.


Assuntos
Compostos de Bário/toxicidade , Cloretos/toxicidade , Glutationa/sangue , Adulto , Compostos de Bário/sangue , Coleta de Amostras Sanguíneas , Fracionamento Celular , Cloretos/sangue , Citosol/metabolismo , Relação Dose-Resposta a Droga , Dissulfeto de Glutationa/sangue , Humanos , Masculino , Plasma/metabolismo , Fatores de Tempo
20.
Pak J Pharm Sci ; 25(3): 549-53, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22713940

RESUMO

Metallo-elements including Vanadium (V) have strong affinity for sulfhydryl (-SH) groups in biological molecules including Glutathione (GSH) in tissues. Because of this fact it was of interest to further investigate the interaction of Ammonium Vanadate [NH(4)VO(3)] with Glutathione as a biomarker of toxicity and the role of Glutathione in the detoxification and conjugation pr(o)Cesses in whole blood components including plasma and cytosolic fraction. Effects of different concentrations of Ammonium Vanadate [NH(4)VO(3)] on the level of reduced Glutathione in whole blood components (Plasma and Cytosolic fraction) were examined. GSH depletion in plasma and cytosolic fraction was Ammonium Vanadate's concentration-dependent. Depleted GSH level was more pronounced with more incubation time period. These findings show that changes in the GSH status produced by Ammonium Vanadate could be due to either by adduct formation of Vanadium and glutathione i.e. (V-SG) or by increased production of oxidized Glutathione (2GSH +V(+5) → GSSG). This change in GSH metabolic status provides some information regarding the mechanism of toxicity by Ammonium Vanadate and the protective role of glutathione.


Assuntos
Glutationa/sangue , Vanadatos/toxicidade , Biomarcadores/sangue , Citosol/metabolismo , Relação Dose-Resposta a Droga , Glutationa/fisiologia , Dissulfeto de Glutationa/metabolismo , Humanos , Vanadatos/metabolismo
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