Pakistan Journal of Pharmaceutical Sciences

Published by Faculty of Pharmacy and Pharmaceutical Sciences, University of Karachi

Online ISSN: 1011-601X

Articles


Table 1 : Comparison between EIN1 & EIN2 
Fig. 2: Concentration of CHL in Aqeous humour (µg/ml) Vs Time (minutes). 
Fig. 3: Time in days Vs %age of drug remained entrapped in niosomes. 
Preparation and characterization of chloramphenicol niosomes and comparison with chloramphnicol eye drops (0.5%w/v) in experimental conjunctivitis in albino rabbits
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January 2012

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Niosomes has gained tremendous popularity as ultimate drug carrier. Lot of research work is being carried out on preparation of niosomes for ophthalmic use having no significant effect on vision and its sustained release pattern. Chloramphenicol niosomes were prepared using two different ratios of cholesterol, drug and surfactant, termed as EIN-1, EIN-2 by ether injection method and their entrapment efficiency, particle size. The in vitro drug release pattern was observed for ten hours. The EIN-2 showed 90% entrapment and released 81% of entrapped drug after 10 hours. Zeta potential & viscosity were determined and in-vivo comparison was made with Chloramphenicol eye drops where it exhibited Cmax of 15 μ g/ml. Stability studies were done to determine shelf life. MIC of selected strain of S. aureus was also determined. EIN 2 niosomal suspension was compared with Chloramphenicol eye drops in experimental conjunctivitis in albino rabbits. In-vitro studies are encouraging as niosomes released about 75% of total entrapped drug by EIN-1 and 81% of total entrapped drug by EIN 2. In vivo study shows that niosomes released the drug in eye in acceptable range and showed a sustained release pattern without affecting the vision. Niosomes were found ultimate ophthalmic drug carriers capable to release drug in sustained and determined pattern.
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Synthesis and evaluation of Mannich bases of benzimidazo[1,2,c] quinazolin-6(5H)-thione for antimicrobial activity

October 2010

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151 Reads

The intermediate Benzimidazo[1,2-c] quinazolin-6(5H)-thione (1) was obtained by cyclization of 2-(2'-aminophenyl) benzimidazole with carbon disulfide. Mannich base (2a-d) of compound (1) was obtained on treatment with Para formaldehyde and secondary aliphatic amines, similarly treatment of (1) with different ketones afforded respective mannich bases (3 e-h). All derivatives synthesized were characterized from IR and 1HNMR spectral data's. Moderate anti bacterial activity was exhibited from 2a-d and from 3f, 3h against S. aureus, E. coli, and E. fecalis but very negligent activity were seen from these compounds when screened against P aeruginosa.

Table 1 : Biological activities of N-substituted bromoacetamides 
Synthesis, characterization and biological screening of N-substituted derivatives of 5-benzyl-1,3,4-oxadiazole-2yl-2″-sulfanyl acetamide

May 2013

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1,062 Reads

A series of new N-substituted derivatives of 5-benzyl-1, 3, 4-oxadiazole-2yl-2ꞌꞌ-sulfanyl acetamide (6a-n) were synthesized in three phases. The first phase involved the sequentially converting phenyl acetic acid into ester, hydrazide and finally cyclized in the presence of CS2 to afford 5-benzyl-1, 3, 4-oxadiazole-2-thiol. In the second phase N-substituted-2-bromoacetamides were prepared by reacting substituted amines with bromoacetyl bromide in basic media. In the third phase, 5-benzyl-1,3,4-oxadiazole-2-thiol was stirred with N-substituted-2-bromoacetamides in the presence of N,N-dimethyl formamide (DMF) and sodium hydride (NaH) to get the target compounds. Spectral techniques were used to confirm the structures of synthesized compounds. Synthesized compounds were screened against butyrylcho linesterase (BChE), acetylcholinesterase (AChE), and lipoxygenase enzymes (LOX) and were found to be relatively more active against acetylcholinesterase.

Synthesis, characterization and biological screening of 5-substituted-1,3,4-oxadiazole-2yl-N-(2-methoxy-5-chlorophenyl)- 2-sulfanyl acetamide

March 2013

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179 Reads

In the current study, a series of 5-substituted-1,3,4-oxadiazole-2yl-N-(2-methoxy-5-chlorophenyl)-2-sulfanyl acetamide was synthesized by converting variously substituted/unsubstituted aromatic organic acids successively into the corresponding esters, hydrazides and then 5-substituted-1,3,4-oxadiazole-2-thiols. Finally the target compounds were obtained by stirring 5-substituted-1,3,4-oxadiazole-2-thiols with N-(2-methoxy-5-chlorophenyl)-2-bromoacetamide in the presence of N,N-dimethyl formamide (DMF) and sodium hydride (NaH). The structures of the synthesized compounds were confirmed based on H-NMR, IR and mass spectral data. The synthesized compounds were screened against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase enzymes (LOX) and were found to be relatively more active against acetyl cholinesterase.

Spectrophotometric determination of natural indoles by complexing with 1,3,5-trinitrobenzene

February 1992

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49 Reads

A spectrophotometric method has been developed for the quantitative determination of some natural indoles by complexing with the electron acceptor 1,3,5-trinitrobenzene and measuring the absorbance in the region 460-529 nm. The RSD of the method is 2.5%. It is simple, rapid and convenient for the routine analysis of indole compounds.

Table 1: Serum S-100B levels (pg/ml) at the different time points in rabbits 
Caffeic acid phenethyl ester decreases the level of S-100B protein after middle cerebral after occlusion in rabbits

August 2009

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136 Reads

Effects of caffeic acid phenethyl ester (CAPE) on the serum S-100B levels were studied as an index for brain damage after permanent middle cerebral artery (MCA) occlusion in rabbits. Twenty rabbits were divided into four groups (n=5): control, sham, non-treatment and CAPE. The right MCA was occluded using a microsurgical procedure with bipolar coagulation and was then transected in non-treatment and CAPE groups. The rabbits in the sham group underwent a surgical procedure but the MCA was not occluded. No surgery was performed in the control group. CAPE was administered after MCA occlusion at the dose of 10 microg/kg, once a day intraperitoneally for 7 days in the CAPE group. Serum S-100B levels were determined on days 1, 2, 4 and 7. Serum S-100B level was significantly increased following permanent MCA occlusion. Posttreatment of CAPE significantly reduced the serum S-100B level. This study demonstrated that CAPE is capable of attenuating increased serum S-100B level induced by MCA occlusion in rabbits. CAPE may be useful as a neuroprotective agent.

Novel indium-111 labeled gastrin peptide analogues (MG-CL1-4): Synthesis and quality control

March 2013

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334 Reads

Radiolabeled neuropeptides are widely investigated to diagnose and therapy of tumors. These peptides get internalization after binding with particular receptors at the surface of cells and finally move to lysosome. Internalization into tumor cells helps in mapping the infected site. Minigastrin peptide analogues (MG-CL1-4) were synthesised and labeled with 111-In radioisotope under different sets of conditions for imaging CCk-2 receptor bearing tumors. Different parameters such as temperature (80-100°C), pH (4-12), incubation time (5-30 minutes) and dilution effect were investigated to get the maximum labeling yield and stability. The results indicated that MG-CL1-4 is successfully labeled with indium-111 at pH 4.5 with heating at 98°C for 15 minute. At these conditions i.e. heating, pH and incubation minimum oxidized and maximum labeling yield, more than 94 %, was obtained. The labeling stability was studied by incubating the radiolabeled complex for predefined time points in PBSA and blood serum. Results show that more than 90% radiolabeled MG-CL1-4 remained intact.

Suitability of Gelucire 50/13 for controlled release formulation of salbutamol sulphate

January 2012

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344 Reads

Gelucire 50/13 (G50/13) was assessed to develop controlled release formulation of salbutamol sulphate (SBL) a highly water soluble drug by semisolid matrix filling capsule technique. Drug release profiles of SBL release by using G50/13 and its blends with other hydrophilic or hydrophobic materials were investigated. Lipid matrix formulations prepared with increasing amount of polymer showed a substantial decrease in release rate of the drug while increasing drug amount in fixed polymer concentration did not significantly affect the release profile. Polyethylene glycol 6000 caused an increased water uptake resulting in fast erosion of the matrix whereas cetostearyl alcohol and stearic acid caused retardation in drug release. These findings confirm that a considerable amount of Gelucire is required alone or in combination with hydrophobic substances in order to sustain the release profiles of water soluble drugs. More linear profile was obtained by using matrix comprising Gelucire/stearic acid blend in more than 85% that was comparable to standard, Ventolin SR tablet. The test formulation showed a significant decrease at pH 1.0 and the drug release rate increased at high stirring speed. Moreover, short term stability of controlled release test formulation indicated slight increase in dissolution rate at high temperature.

Table 1 : Radical scanenging activity and total phenol and flavonoids contents in peels and tissues of 13 most commonly used citrus spp. 
Antioxidant activity, phenol and flavonoid contents of 13 Citrus species peels and tissues

August 2009

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19,189 Reads

Methanolic extracts of 13 commercially available citrus spp., peels and tissues growing in Iran were investigated for their antioxidant activity by DPPH method. IC50 for antioxidant activity ranged from 0.6-3.8 mg ml(-1). Total phenolic content of the citrus spp. samples (based on folin Ciocalteu method) varied from 66.5 to 396.8 mg gallic acid equivalent/g of extract and flavonoids content (based on colorimetric AlCl3 method) varied from 0.3 to 31.1 mg quercetin equivalent/g of extract. There were no correlation between the total phenolic and/or flavonoids contents and antioxidant activity in tissues and/or peels.

Fig. 1: Changes in BW over 14 days in male (a) and female (b) mice after a single oral FRE treatment. 
Table 1 : Changes in absolute and relative organ weights in male mice after a single oral FRE treatment 
Table 2 : Changes in absolute and relative organ weights observed in female mice after a single oral FRE treatment 
Fig. 4: Histopathological changes in the spleen. 
Single-dose oral toxicity of fermented rice extracts (FREs): A 14-day observation

January 2014

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207 Reads

The aim of present research was to determine the acute oral toxicity of fermented rice extracts (FREs), in female and male ICR mice. To investigate the toxicity and identify target organs, FREs were orally administered once to male and female ICR mice at doses of 0 (vehicle control), 500, 1000, or 2000 mg/kg body weight (BW). Effects on mortality, BW, and clinical signs were monitored over 14 days, including changes in the weights and histopathological characteristics of 14 organs, as described in the Korea Food and Drug Administration (KFDA) Guidelines (2009-116, 2009). No treatment-related mortality was observed during the 14-day observation period in either gender. In addition, no FRE-related change was observed in BW or organ weight (OW), clinical indicators, or histopathological findings in this study. Our results suggest that the FRE is non-toxic in mice and is therefore likely to be safe for clinical use. The approximate LD and LD50 in mice after single oral dose of FRE are greater than 2000 mg/kg in female and male ICR mice. Additionally, no specific target organ or negative clinical indicator was detected in this study.

Table 2 : Properties of the prepared granules and Lamivudine USP tablets. 
Effect of starch 1500 as a binder and disintegrant in lamivudine tablets prepared by high shear wet granulation

November 2008

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14,290 Reads

High shear wet granulation is a preferred manufacturing method of tablets. It allowed for rapid production of compressible granulations. The resultant granulation characteristics depend on a combination of formulation properties and processing parameters. Fully pregelatinized starches are currently being used as binders in wet granulated formulations. But due to the gelatinization, much of the disintegration properties are lost. Partially pregelatinized starches (starch 1,500) have a mixture of properties of both native and fully gelatinized starches; made them useful as both a binder and a disintegrant in wet granulated formulations. Starch 1,500 performed as an excellent binder producing a granulation that was compressible and produced lamivudine tablets of improved hardness and friability compared with those prepared with povidone. The formulation of lamivudine tablets with starch 1,500 exceeded the disintegration and dissolution performance of the povidone formulation that utilized a super disintegrant. High shear wet granulation is also well suited for the use of partially pregelatinized starches.

Bacteriocin (BAC-IB17): screening, isolation and production from Bacillus subtilis KIBGE IB-17

January 2012

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2,420 Reads

Bacteriocins are peptides produced by a variety of different microbes and have antimicrobial activity against closely related species. These antimicrobial agents are gaining more and more attention as an alternative therapeutics not only in pharmaceutical but also as a preservative in food industries. In this study several bacterial strains were isolated from soil and screened for bacteriocin production. Among them, one strain identified as Bacillus subtilis KIBGE IB-17 on the basis of taxonomic studies and confirmed by 16S rDNA analysis. This newly isolated strain showed antibacterial activity against several Gram positive and Gram negative bacteria. Different concentrations of tryptone, yeast extract and NaCl and physiochemical factors such as temperature, pH and incubation period were selected as variables for maximum production of bacteriocin by using agar well diffusion method and significant effects of variables were observed on the production of Bac-IB17. A newly designed modified TY medium showed maximum bacteriocin production containing 1.0% tryptone, 0.5% yeast extract and 0.5% NaCl. Maximum Bac-IB17 production was observed at 37° after 24 hours with initial medium pH 7.0. Bacillus subtilis KIBGE IB-17 is capable of producing a bacteriocin at a wide range of pH and temperature that makes it an ideal strain that can be used for the production of bacteriocin on industrial scale level. The identification and production of such bacteriocin like compound against a wide spectrum of microbial species is very important for food and pharmaceutical industry.

Antimicrobial spectrum, production and mode of action of staphylococcin 188 produced by Staphylococcus aureus 188

February 2004

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123 Reads

Staphylococcus aureus 188 has been shown to produce bacteriocin-like inhibitory substance known as staphylococcin 188. It has a broad-activity spectrum against Micrococcus luteus, Streptococcus pneumoniae, Streptococcus faecalis, Streptococcus viridans, Corynebacterium diphtheriae and several staphylococcus species. The arbitrary unit of staphylococcin 188 against Micrococcus luteus was 1280 AU/mL. Its production with simultaneous measurement of activity was monitored and was found to produce maximum amount of staphylococcin after 7 hours of incubation. Mode of action of the staphylococcin 188 on the sensitive cells was bactericidal rather than bacterioloytic.

5-HT-1A receptor responsiveness following subchronic administration of buspirone

November 2006

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64 Reads

Anxiety and its disorders have long been known to be familial. Anxiety levels are associated with low social connectedness and high environmental threats. Studies provide evidence that anxiety disorders may be link to malfunctioning of serotonin neurotransmission. The present study is designed to monitor serotonin-1A (5-HT-1A) receptor responsiveness following subchronic administration of a serotonergic anxiolytic buspirone. Administration of 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT) at a dose of 0.25 mg/kg produced comparable syndrome in repeated saline and repeated buspirone injected rats. Cage crossings were significantly lower in repeatedly buspirone injected rats. Decreases in 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) levels were higher in saline than buspirone injected rats. Result suggests that following long term administration of buspirone somatodendritic and postsynaptic 5-HT-1A receptors are desensitized. Role of serotonin 1A receptors in the treatment of anxiety is discussed.

Desensitization of pre and post synaptic 5-HT-1A receptor responses following long term consumption of sugar rich diet: Implications for sugar-induced obesity

November 2008

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163 Reads

The present study concerns the effectiveness of a selective 5-hydroxytryptamine (5-HT)-1A receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) in long term sugar diet treated rats. Male albino wistar rats were divided into control and test groups. Test animals were given sugar (5 g/10 ml water) orally for three weeks. Food intakes and body weight of all rats were measured weekly. After three weeks control and test animals were further divided into two groups i.e. saline injected and drug injected. 8-OH-DPAT at a dose of 0.25mg/Kg was injected to a group of normal diet treated and another group of sugar diet treated rats. Other two groups were injected with saline. 5-HT syndrome and food intakes at 2h and 4h were monitored. Then animals were decapitated to collect brain samples for the estimation of 5-HT and 5-hydroxyindole acetic acid (5-HIAA) levels by HPLC-EC method. We observed that weekly cumulative food intakes increased and body weights decreased in sugar diet treated rats. 8-OH-DPAT produced hyperactivity syndrome in both control and sugar treated rats. But these values were smaller in sugar diet than normal diet treated rats. Hyperphagic effects of 8-OH-DPAT were greater in normal diet than sugar diet treated rats. 5-HT and 5-HIAA levels were not altered. The results suggesting a desensitization of pre as well as postsynaptic 5-HT-1A receptors in rats treated with sugar diet are discussed in the context of a role of sugar diet in the precipitation of obesity and other neuropsychiatric illnesses.

Serotonin-1A receptor responsiveness in stress and following adaptation to stress

May 2007

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47 Reads

Stress is one of the environmental factors that may predispose psychiatric illness such as, depression. Stress may come from external environment in the form of stimuli such as heat, cold, loud noise and lack of oxygen. A deficiency of serotonin (5-hydroxytryptamine; 5-HT) is described in human depression. Parallel studies on experimental animals show that exposure to an uncontrollable stress inducing situation elicits behavioral deficits and increases serotonin metabolism in the brain. Stress-induced behavioral deficits and the increases of brain serotonin did not occur when the stress was administered repeatedly for 5 days, suggesting adaptation has occurred. The present study shows that responses to 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT), a selective 5-HT 1A agonist decreased following exposure to single stress and the decreases were normalized following adaptation to stress. The drug 8-OH-DPAT was also found to attenuate stress-induced behavioral deficits. The results are discussed in the context of stress-induced psychiatric disorder such as, depression and its treatment by 5-HT 1A agonist.

The derivatives of 3-(1H-benzikmidazole-2) propanoic acid synthesis and analgetic and anti inflammatory activity

February 1989

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15 Reads

Several derivatives of 3-(1H-benzimidazole-2) propanoic acid (Procodazol) were prepared using some aldehydes by the condensation reaction. The resulting products were lactam and acid derivatives. According to the spectral studies it was found that the hydrogen atoms of the 3-methylene group of 3-(1H-benzimidazole-2) propanoic acid take part in the reaction. 3-(2'-(Acetoxyphenyl) methylene)-2, 3-dihydro-1H-pyrrole (1, 2a) benzimidazole lone (3c) was found to possess some analgetic properties.

Exercise preconditioning reduces ischemia reperfusion-induced focal cerebral infarct volume through Up-regulating the expression of HIF-1α.

March 2015

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43 Reads

To study the effect and mechanism of exercise preconditioning on focal cerebral ischemia reperfusion induced cerebral infarction via rat model; Sixty Sprague Dawley rats were divided into three groups at random: ischemia reperfusion group (IR, n=24), sham group (sham, n=12) and exercise preconditioning group (EP, n=24). Group EP carried out moderate exercise preconditioning for 4 weeks (swimming with non-weight bearing, 60 minutes/day, 6 days/week), Rats in Group EP and IR were established cerebral ischemia reperfusion injury model by Zea Longa's thread method. The cerebral infarct volume in rat of different group was evaluated after 2%TTC staining, expression of HIF-1α in rats' brain was detected by real-time RT-PCR, immunohistochmeistry method and western blot. No cerebral infarction and significant expression of HIF-1α in Group sham. Compared with Group IR, there was smaller infarct volume and stronger HIF-1α expression in Group EP (P<0.05). Moderate exercise preconditioning reduces ischemia reperfusion induced focal cerebral infarct volume through up-regulating the expression of HIF-1α.

The effect of sodium hyaluronate treating knee osteoarthritis on synovial fluid interleukin -1β and clinical treatment mechanism

January 2015

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43 Reads

In order to explore the influence of sodium hyaluronate on knee osteoarthritis (KOA) patients synovial fluid interleukin -1β (IL-1β) and analyze its clinical mechanism, this study analyzed 40 cases of KOA patients in our hospital's orthopaedic department, randomly divided them into two groups: Sodium hyaluronate group (group A) and normal saline group (group B), each consists 20 patients. Besides, we selected another 20 patients as normal control group. Group A treated knee joint cavity by injecting sodium hyaluronate, and group B injected knee joint cavity in equal amount of normal saline, once a week for five weeks. Collect respectively knee joint synovial fluid in patients of group A and group B before treatment and after five weeks of treatment, detect the content of knee joint synovial fluid IL-1βin of all the three groups by using enzyme linked immunosorbent assay (ELISA). We can conclude that (1) IL-1β content of knee joint synovial fluid in KOA patients before treatment was significantly higher than healthy people; (2) IL-1β content of group A knee joint synovial fluid after treatment was significantly reduced than before treatment, there was no significant difference for group BIL-1β content before and after treatment; (3) there was no significant difference between group A knee joint synovial fluid IL-1β content after treatment and healthy people. Thus it can be proved that content of IL-1β in knee joint synovial fluid KOA patients is higher than healthy people; sodium hyaluronate can reduce the content of IL-1β in synovial joints and can be effective in the treatment of knee osteoarthritis.

Rapid colorimetric assay of diclofenac sodium tablets using 4-carboxyl-2,6-dinitrobenzene diazonium ion (CDNBD)

April 2006

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2,400 Reads

This study describes a novel simple, rapid and sensitive colorimetric assay method for diclofenac sodium tablets. The method is based on a simple aromatic ring derivatization technique using newly developed 4-carboxyl-2, 6-dinitrobenzenediazonium ion (CDNBD) as chromogenic derivatizing reagent with subsequent formation of an azo dye. The diazo coupling reaction was carried out between CDNBD and diclofenac. Optimization studies for time and temperature was conducted using the method of steepest ascent. The UV absorption spectrum was recorded and the stoichiometric ratio for the drug and reagent was done by continuous variation method. Optimal calibration range was fixed (1-way ANOVA) and then the method was applied to dosage form analysis. Comparison of dosage form analysis was done with the BP HPLC method. The diazo coupling reaction is very fast and optimization studies established an optimal reaction immediately after mixing the reaction mixture in a vortex mixer for 10 sec. A new absorption maximum (lambdamax) at 470 nm was selected as analytical wavelength. The assays were linear over 1.35-10.8 microg/ml of diclofenac and the reaction required a 2:1 reagent/drug stoichiometric ratio. The new method has a low limit of detection of 0.27 microg/ml, and was reproducible over a three-day assessment of precision (RSD 2.31%). The method has been successfully applied to the assay of diclofenac sodium slow-release tablets and found to be of equivalent accuracy (p>0.05) with the official (B.P 1998) HPLC method. The new method has distinct advantages of speed, simplicity, sensitivity, and more affordable instrumentation and could find application as a rapid analytical method for diclofenac sodium tablets.

Fig. 1: Plasma testosterone concentrations in control (n=4), DMSO (n=4) and treated (n=4) groups at day 1, 7, 14 and 21. 
Fig. 4: Photomicrograph of T.S. of adult rat testes (100X) showing effect of 2,8-Dimercapto-6hydroxypurine on spermatogenesis in single seminiferous tubule after 21 days treatment. (a) Control (b) Treated (c) DMSO; (Sp) Spermatogonia, (PS) Primary spermatocyte, (SS) Secondary spermatocyte, (SC) Sertoli cell, (S) Spermatozoa. 
Effect of i.p antithyroid drug 2,8-Dimercapto-6-hydroxypurine administration (20 mg/kg) on tunica thickness, seminiferous tubule diameter, seminiferous tubule epithelial height in seminiferous tubule of treated (n=4) and DMSO (n=4) as compared to control (n=4), after 21 days.
Effect of an anti-thyroid drug, 2,8-Dimercapto-6-hydroxy purine on reproduction in male rats

April 2012

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123 Reads

This histomorphological study is designed to evaluate the peripheral action of 2,8-Dimercapto-6-hydroxypurine (an antithyroid drug) on male reproductive system. The drug was administered as i.p. injection for 21 days to investigate its role on morphology of intratesticular cells and plasma testosterone level. Adult male rats (n=12), divided into three groups i.e. control, dimethylsulphoxide (DMSO) and 2,8-Dimercapto-6-hydroxypurine treated groups and treated with saline, DMSO and 2,8-Dimercapto-6-hydroxypurine for 21 consecutive days respectively. Blood samples were collected at day 1, 7, 14 and 21 and analyzed by using EIA systems. All the animals were scarified on 22nd day and testicular tissues were studied by histomorphpological assesment. 2,8-Dimercapto-6-hydroxypurine caused a significant decrease (P<0.0001) in mean testicular cell population, testicular cell diameter and resulted in arrested spermatogenesis. A significant decrease (P<0.0001) was observed in mean Sertoli and Leydig cell population and diameter in treated group. Similarly a significant decrease was observed in plasma testosterone levels at days 1, 7 and 14 (P<0.05) and further decrease by day 21 (P<0.01) of drug treatment. The present study suggests that 2,8-Dimercapto-6-hydroxypurine is a negative modulator of reproductive system as it suppressed the plasma testosterone level and proliferation of different testicular cell types in adult male rats.

Bioavailability study of tablet Bezafibrate 200 mg (Lipocor)

February 2002

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533 Reads

In order to determine the ultimate quality of any formulated dosage form and rationalize the therapeutic plan as well as to individualize the prescription, in vivo measurement of drug is the modem and specialized expertise of the clinical/research area of pharmacy practice, which provides effectiveness and assures the safety of drugs. All pharmacological, therapeutic or toxic responses are subject to reaching of drug at the site of action through connective tissue. Other than physico chemical properties of drug, there are numerous factors from manufacturing process to biochemical behaviour of the individual which resist in the absorption, distribution, metabolism and elimination of drugs in the biological system. Bezafibrate Tablet 200 mg (Lipocor) an oral conventional formulation manufactured by Efroze Chemical Industries (Pvt.) Ltd. was investigated for bioavailability followed by pharmacokinetic studies on adult, male, healthy, human local population. For this purpose, a sensitive, specific and validated method was used for the estimation of bezafibrate in blood. HPLC was performed on a reversed phase C18 column (flow rate 1.5 ml/min, UV = 230 nm) with 0.02 M buffer of KH2PO4 (Adjusted pH 3.5 with Phosphoric Acid) and Methanol (40: 60) whereas extraction of the drug from the plasma was carried out by deproteinization of plasma according to classical method described in previous studies (Obaid A. et al., 1999). Peak level (Tmax) of Bezafibrate Tablet 200 mg (Lipocor) was observed at about 1.42 +/- 0.53 hours after the dose and practically free Bezafibrate Tablet 200 mg (Lipocor) could be detected in blood after 9 hours. Cmax of the investigated formulation of Lipocor register mark or target was 1732 +/- 374.2 ng/ml. Area under curve (AUC) was 5198.65 +/- 1231.8 ng. hr/ml.

Staphylococcal resistance against five groups of life saving antibiotics in the year 2003-2005

November 2013

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58 Reads

In the year 2003 to 2005 a prospective study was conducted to find out the predominance of Staphylococcus (Staphylococcus aureus) resistance pattern in opposition to five life saving antibiotics as these are the sole agents to treat critically ill patients in hospitals. During the period of two years almost 2500 samples of bacterial culture were taken from different pathological laboratories and hospitals in Karachi. Among these 1500 were Gram positive cocci and 1000 samples were identified as Staphylococcus aureus. Life saving antibiotics were taken from five different groups and by mean of disk diffusion technique antibiogram of Staphylococcus aureus against these antibiotic were determined. During the course of study imipenem showed 11%, amikacin exhibited 58%, cefipime showed 31%, vancomycin and piperacillin/tazobactam displayed 24% resistance against Staphylococcus aureus. Imipenem was found to be most effective against Staphylococcus aureus.Resistance to other antibiotics developed quickly in Staphylococcus aureus collected from clinical areas where these antimicrobial agents are extensively used.

Fig. 1 : Agarose gel electrophoresis of restriction digestion products for ecNOS codon 298. Lane 1, 100 bp DNA ladder. Lane 2-9, restricted PCR products of ACS patients and controls. 
Association of Endothelial Nitric Oxide Synthase (eNOS) gene polymorphism (Gin 298 Asp) with coronary artery disease in subjects from Multan, Pakistan

March 2014

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304 Reads

Acute Coronary Syndrome (ACS) is the most common disease and cause of mortality in both genders across the world and certain risk factors i.e. age, gender, smoking, diabetes, hypertension, drugs usage, weight etc are known to be associated with the disease. The aim of this study was to find if there is any correlation exists between ACS and hereditary genetic defect in endothelial nitric oxide synthase (ecNOS) gene as eNOS generates Nitric oxide in blood vessels and regulates the vascular tone hence directly affecting the cardiovascular function. Single nucleotide polymorphism (SNP) (Glu 298 Asp) in ecNOS was determined in 280 subjects, from Southern Punjab (in Pakistan) population, including (160 ACS patients and 120 healthy controls) by PCR-RFLP method and genotype was correlated with various risk factors as well as with serum cholesterol and triglyceride levels. Our results indicated that the genotype Glu 298 Asp was not associated with ACS but when various studied parameters were compared among patients suffering from various forms of ACS and their healthy controls, it was observed that age (45-55 years) (P = 0.05), gender (male) (P < 0.001), education (P<0.001), family history (P=0.03), hypertension (P<0.001), diabetes (P<0.01) and smoking habit (P = 0.03) were the significantly different parameters among them and may be associated with the incidence of cardiovascular disease. Cholesterol (161.5±79 mg/dL) level was found to be higher in patients (P = 0.04) than controls while triglyceride remained unaffected (P = 0.87) in both groups.

Fig 1 : Results of antimicrobial susceptibility patterns of five different antibiotics against Staphylococcus aureus. 
Fig 2 : Results of antimicrobial susceptibility patterns of five different antibiotics against Staphylococcus epidermidis. 
Bashir A, Mujahid TY, Jehan NAntibiotic resistance profile: isolation and characterization of clinical isolates of staphylococci from patients with community-acquired skin infections. Pak J Pharm Sci 20:299-304

November 2007

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399 Reads

Although most bacterial infections of the skin bear out to be minor in nature, a few such dermatologic entities are major, to the spot of yet being fatal. The mortality rate is usually up to 30% to 50% and depends upon the type of infection, original disease, and resistant type. In this study hundred and five bacterial strains were isolated from skin wounds, burns and acne patients from hospitals at different locations in the cosmopolitan city of Karachi. These bacterial strains were identified by conventional methods. Seventy two percent (72%) of total isolated organisms were found to be Staphylococcus aureus while the remaining thirty three percent (33%) were Staphylococcus epidermidis. The antibiotic resistance of identified organisms was carried out by disc-diffusion method with commercially available disc of five antibiotics having different mode of actions such as cell wall synthesis inhibitors, membrane permeability alternatives and DNA synthesis inhibitors. Staphylococcus aureus show more resistant to these antibiotics as compared to Staphylococcus epidermidis. The most effective antibiotic for Staphylococcus aureus is vancomycin showing 80.5% efficacy, then methicillin with 68.0% efficacy, erythromycin with 55.6% efficacy, novobiocin with 54.1% efficacy and then bacitracin with 25.0% efficacy. The most effective antibiotic for Staphylococcus epidermidis is methicillin showing 84.8% efficacy, then vancomycin with 81.2% efficacy, novobiocin with 63.6% efficacy, erythromycin with 42.4% efficacy and then bacitracin with 27.8% efficacy.

High-level expression of fusion peptide Dybowskin-2CDYa and hEGF in E. coli and its dual function

May 2014

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33 Reads

Dybowskin-2CDYa (Dy2), with a broad antimicrobial spectrum and low hemolytic feature, is a newly discovered type of antimicrobial peptides from Rana dybowskii. In order to get a dual function peptide which inhibits bacterial growth and promotes cell proliferation, we cloned the gene of Dy2and hEGF (human epidermal growth factor) into the prokaryotic expression vector pET-30a(+). With isopropyl-β-D-thiogalactoside (IPTG) induction, a 13.7KDa peptide with a 6×His tag was highly expressed in the form of inclusion in E. coli BL2l (DE3). SDS-PAGE and western-blot confirmed the expression of the fusion peptide hEGF-Dy2. Under the optimized condition of 1.0mmol/L IPTG induction and incubation time 4h at 37o, the yield of hEGF-Dy2reached 30mg/L following purification on nickel-nitrilotriacetic acid (Ni-NTA) metal affinity chromatography matrices. The purified fusion peptide showed significant antibacterial activities against Staphylococcus aureus, Escherichia coli O157, Pseudomonas aeruginosa and proliferating activities on NIH3T3. These results indicated that the fusion peptide might have a good prospect in therapy of trauma and burns.

Toxicity of crude neem extracts (N-4) and (N-9) against late 2nd instar larvae of Musca domestica L. (PCSIR strain)

February 1991

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18 Reads

The LD50 of crude neem extract (N-4) and (N-9) was found to be 4.80% and 0.47%, respectively. The range of mortality was found to be increasing (at 95% confidence limit) with increase in concentration of solution.

Synthesis, characterization and biological activity of some 1, 3,4-thiadiazol derivatives

October 2011

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60 Reads

Thiadiazoles are their derivatives exhibit a wide variety of pharmacological activities such as Antibacterial and anti-inflammatory. In the present study we have synthesized derivatives some 2,5 substituted 1,3,4- thiadiazoles. The structures of these synthesized compounds were confirmed by IR, NMR, and MASS spectra data. These compounds were evaluated for varies biological activities such as antibacterial and anti-inflammatory activity.

Clinical observation of 32 cases with transplantation of autologous bone marrow stem cells on diabetes and its complications

November 2014

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22 Reads

By observing the curative effect of autologous stem cells changes before and after the treatment, to explore the stem cell treatment of diabetes and its complications. 32 patients were type 2 diabetic patients with different complications. By intravenous injection of autologous stem cells, observe improving symptoms, signs and auxiliary examination of patients after three months. Evaluation index: glycated hemoglobin level; ankle brachial pressure index (ABI); limb electromyogram; 24h urine protein quantity. Diabetic complications of different systems and glycated hemoglobincan be effectively improved. This research and application of autologous bone marrow stem cell transplantation for treatment of type 2 diabetes chronic complications achieves certain results, non-toxic side effects occuring. Just only preliminary observes the clinical effect, a small sample size. We need to expand the sample and observation period further for the long-term efficacy and side effects.

3D protein structure prediction of influenza A virus based on optimization genetic algorithm

May 2014

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19 Reads

The 3D structure of close polymer is constituted by the interaction of close contact couples among amino acid residues. In this paper, 3D protein structure of influenza A virus was predicted. Twenty kinds of amino acid residues were divided into four categories according to the number of close contact couples. The stable structure with minimum energy was obtained by using optimization genetic algorithm. The HNXP 3D lattice model was established to predict the 3D protein structure. It can be concluded that the two kinds of structures are significantly similar by computing the similarity.

3-[(2-chloroquinolin-3-yl)methyl]quinazolin-4(3H)-ones as potential larvicidal agents

July 2013

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45 Reads

The larvicidal effect of series of 3-[(2-chloroquinolin-3-yl)methyl] uinazolin-4(3H)-ones, 5a-e, against Chironomus tentans Fabricius has been investigated. The results showed that tested compounds demonstrated strong larvicidal activity, and caused high percentage of mortality after 24 h at the doses of 40-100 g/ml, especially in the case of 3-[(2-chloro-8-methyquinolin-3-yl)methyl]quinazolin-4(3H)-one, 5b, that act as a promising larvicidal agent.

Computational study on the geometry optimization and excited - State properties of Riboflavin by ArgusLab 4.0.1

May 2013

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477 Reads

Riboflavin (vitamin B2) belongs to a group of respiratory enzymes that occur widely in animals and plants participating in vital oxidation- reduction processes in the body. A computational study was conducted on riboflavin by ArgusLab 4.0.1 to obtain the most active conformation of riboflavin and to analyze its excited-state properties. The best conformation of riboflavin was found to be -199.2173 kcal/mol which is the minimum potential energy calculated by geometry convergence function by ArgusLab software; performed according to Hartree-Fock calculation method. Electronic transition states (ground and excited), were also calculated and visualized by semi-empirical ZINDO method by ArgusLab from which molecular properties such as energies, wave function and dipole moments were established. All the results obtained from geometry optimization and excited-state properties lead us to delineate the active sites with charged groups of riboflavin to interact with the receptors. Such types of investigations are significant for drug-receptor interactions.

Computer aided conformational analysis of sulfonated azo dyes diammonium orange G (C16H10N2O7S2 (NH4) x 4H2O

August 2005

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39 Reads

The present work describes the conformational analysis of diammonium orange G (C16H10N2O7S2 (NH4) x 4H2O) by using Kitaigorodsky function. The minimum potential energy was found to be -0.0099839 at omega1 = 16 degrees and omega2 = 360 degrees.

Effects of olive leaves extract on LDL oxidation induced-CUSO 4in vitro

July 2012

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194 Reads

Oxidation of low-density lipoprotein (LDL) has been strongly implicated in the pathogenesis of atherosclerosis. The use of some natural antioxidant and herbal medicine may lead to the inhibition of production of oxidized LDL and may decrease both the development and the progression of atherosclerosis. The aim of this study was to investigate the effects of Olive leaves ethanol extract (OLE) on LDL oxidation induced-CuSO(4) quantitatively in vitro. Low-density lipoprotein was incubated with CuSO(4) and the formation of conjugated dienes and thiobarbituric acid reactive substances (TBARS). Inhibition of this Cu-induced oxidation was studied in the presence of vitamin E and various concentration of OLE. It was demonstrated that OLE reduced the formation of conjugated dienes and TBARS of LDL against oxidation in vitro (p<0.05). The inhibitory effects of the OLE on LDL oxidation were dose-dependent at concentrations ranging from (2μg/ml) to (200μg/ml). Moreover, we compared effects of OLE on LDL oxidation with vitamin E as positive control. This study showed that OLE is a source of potent antioxidants and prevented the oxidation of LDL in vitro and it may be suitable for use in food and pharmaceutical applications.

Toxicity of nicotine derivatives and their effect on the protein pattern of 4th immature stage of red cotton stainer Dysdercus koenigii (Fabr) (Hemiptera: Pyrrochoridae)

February 1990

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10 Reads

Toxicity of Nicotine dust and Nicrotine cyanurate was observed against the 4th immature stage of Dysdercus koenigii (Fabr.) by injection method. Mortality rates were noted after 24 hours of treatments. LD50's were calculated as 7.2 microg/nymph and 9 microg/nymph for nicotine dust and nicotine cyanurate respectively. Changes in the flow of protein metabolites occur with higher and lower doses of both the compounds.

Hypoglycemic potential of tablet Metformin 500 mg (Glucophage & Metphage): a pharmacological end point evaluation

August 2003

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117 Reads

Quantitative determination of pharmacological response or clinical end point study is essential for successful evaluation of clinical pharmacology and Bioavailability/ Bioequivalence issues. Stride has been made for proper selection of a quality drug product from the various available therapeutic, which is the prime responsibility of Health care provider and specially pharmacist. Study was conducted in respect to investigate the Pharmacodynamics response, differences and individual variation of oral, Metphage (Metformin 500 mg tablet) as a test formulation manufactured by Efroze Chemical Industries (Pvt.) Ltd. and Glucophage (Metformin 500 mg tablet) as a reference formulation manufactured by Merck Marker. Blood glucose levels/hypoglycemic effect produced by both formulation were studied under cross over trial with respect to placebo/control treatment and result were discussed accordingly. There were no hypoglycemic episodes requiring medical intervention and/or pharmacologic therapy so the patients can easily manage it. Results of the study clearly suggest that formulation manufactured by Efroze Chemical Industries (Pvt.) Ltd. is near to the standard formulation and produced comparable results. No significant differences in pharmacodynamics was observed, however, minor differences might relate with inter individual variation in human volunteers and in different formulation as well as different pharmaceutical unit. Although this data assure the ultimate quality of Metformin 500 mg tablet manufactured by Efroze Chemical Industries (Pvt.) Ltd. but every Generic equivalent should be studied for assurance of safety and efficacy because life of patient is a matter of concern. Such type of study would provide better evaluation of the performance of a drug from a dosage form.

Tranilast attenuates TGF-β1-induced epithelial-mesenchymal transition in the NRK-52E cells

January 2014

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48 Reads

We previously reported that tranilast can halt the pathogenesis of chronic cyclosporine nephrotoxicity in rats via the transforming growth factor-α (TGF-α) /Smad pathway, an important signaling system involved in epithelial-mesenchymal transition (EMT), but the exact underlying cellular mechanisms are not yet clear. Thus, by selecting TGF-α1-induced normal rat kidney proximal tubular epithelial cells (NRK-52E) as a model, we demonstrated potential modifying effect of tranilast on EMT-induced by TGF-α1 in vitro. NRK-52E cells were incubated with the blank vehicle (Dulbecco's modified Eagle's medium and F-12 (DMEM/F12) added with 10% fetal bovine serum (FBS)), 10 ng/ml TGF-α1 alone or together with 100, 200 or 400μM tranilast for 48 h after incubation in medium containing 1% FBS for 24 h. Cell morphological changes were observed to confirm occurrence of EMT. Protein expressions of two typical markers of EMT, E-cadherin and α-smooth muscle actin (α-SMA), were assessed by western blotting and flow cytometry, respectively. Our results showed that TGF-α1 induced spindle-like morphological transition, the loss of E-cadherin protein and upregulation of expression of α-SMA. However, the TGF-α1-produced changes in cellular morphology, E-cadherin and α-SMA were inversed by tranlilast in concentration-dependent manner. Our findings indicate that tranilast can directly inhibit EMT. Thus, it may be implied that regulation of EMT be the target to prevent renal tubulointerstitial fibrosis.

Role of Ki-67 in acromegalic patients with hyperprolactinemia: Retrospective analysis in 61 Chinese Patients

March 2015

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16 Reads

To evaluate the specific characteristics in acromegalic patients with hyperprolactinemia by analyzing the differences between patients with different Ki-67 values. Between 2002 and 2010, a set of data on 61 patients undergoing transsphenoidal surgery was available at the Department of Neurosurgery, Provincial Hospital Affiliated to Shandong University. Patients were divided into Ki-67 >3% group and <3% group. A retrospective analysis of clinical, hormonal, immunohistochemical, and imaging was observed in all patients. There were no significant differences in age, gender, tumor size and apoplexy between the two groups. Time interval in Ki-67 ≥3% group was longer than <3% group (P=0.037). Patients in Ki-67 >3% group had a higher rate of invasiveness (P=0.048), higher incidences of diabetes mellitus (P=0.036), coarse facial features (P=0.048), large hands and feet (P=0.003), higher GH levels (P<0.05), higher diabetes insipidus rate (P<0.001), and more frequent recurrence (P=0.011) than Ki-67 <3% group. Patients with higher Ki-67 value harbored longer time interval, more aggressive tumors, more acromegaly manifestations, higher GH level, and higher recurrence than patients with lower Ki-67 value.

In vitro study of antigrowth capacity and antiacid capacity on Sreptococcus sobrinus 6715 of sorghum procyanidin dimers

May 2014

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18 Reads

The bacteria grow in oral cavity and product acids, which could induce dental caries. In this study, in order to obtain the relationship between procyanidin dimers from sorghum episperm (sorghum procyanidins, SPC) and its anticaries effect. The extract of SPC purified by macroporous resin was divided into three parts by gel chromatography, marked as GPC-1, GPC-2, and GPC-3 in order. The ESI-MS and MS/MS analysis indicated that the main composition of GPC-2 was procyanidin dimers. In addition, the capacities of antigrowth and antiacid on Sreptococcus sobrinus 6715 were analysised to investigate the effect of SPC dimers in protecting against dental caries. The results indicated that the minimum inhibitory concentration (MIC) of SPC dimers was 16 mg/mL. Furthermore, the SPC dimers had notable preventive effect < against the acid production of Sreptococcus sobrinus 6715 compared with the control group, which suppressed in a dose-dependent manner by pH decline. These findings indicated that SPC dimers had potential to be used as anticaries preventive medicine due to its strong capacity of antigrowth and antiacid.

Effect of dextran 70 blood substitute on diazepam binding by human serum albumin

August 1997

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11 Reads

Diazepam binding studies with dextran 70 and human serum albumin (HSA) were carried out using centrifugation and a membrane ultrafiltration technique to separate the drug protein complex and the free microsolute. The molecular filtration method was found to be precise and reproducible with very little variations. The binding of diazepam to dextran was significant but considerably smaller when compared with the extensive binding of diazepam to HSA. The results of these studies demonstrate that diazepam binding of HSA is altered in the presence of dextran. Diazepam binds to dextran resulting in displacement of diazepam from albumin binding sites. The contributing effect of dextran to overall diazepam binding increased as the dextran concentration increased and the HSA concentration decreased. However, the net result of HSA dilution with dextran 70 was still an increase in the percent free diazepam. Various concentrations of dextran 70 significantly displaced HSA bound diazepam in all the mixtures studied.

Pharmacokinetic differences of some generic tablet gliclazide 80 mg on Pakistani population

February 2004

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500 Reads

The goal of rational drug therapy is to produce a desired pharmacological response in an acceptable and predictable manner while minimizing the occurrence of undesired events. The Pharmacokinetics of different generics of tablet gliclazide 80 mg was investigated on healthy (10 x 2), Pakistani subjects. For this exploration an open-label, randomized, two-period crossover (Balanced in Complete Block Design) study, was conducted The out come of the said study suggests that all generics were found analogous regarding pharmacokinetic behavior in-spite of having different excipients, concentration of excipients, sources of raw material, manufacturing process, machinery, resources and also inter individual variation of the study. Results of the study also undoubtedly advocate that generics manufactured in different manufacturing units of Pakistan are near to the standard formulation and produce comparable results. No significant differences in pharmacokinetics parameters were observed, however, minor differences might narrate with inter individual variation in human volunteers and in different generic as well as different pharmaceutical unit.

Formulation and in vitro evaluation of clotrimazole gel containing almond oil and Tween 80 as penetration enhancer for topical application

May 2013

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5,421 Reads

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.

Carbopol 934, 940, and Ultrez 10 as viscosity modifiers of palm olein ester based nano-scaled emulsion containing ibuprofen

January 2013

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951 Reads

Micro-emulsions and sometimes nano-emulsions are well known candidates to deliver drugs locally. However, the poor rheological properties are marginally affecting their acceptance pharmaceutically. This work aimed to modify the poor flow properties of a nano-scaled emulsion comprising palm olein esters as the oil phase and ibuprofen as the active ingredient for topical delivery. Three Carbopol ® resins: 934, 940 and Ultrez 10, were utilized in various concentrations to achieve these goals. Moreover, phosphate buffer and triethanolamine solutions pH 7.4 were used as neutralizing agents to assess their effects on the gel-forming and swelling properties of Carbopol ® 940. The addition of these polymers caused the produced nano-scaled emulsion to show a dramatic droplets enlargement of the dispersed globules, increased intrinsic viscosity, consistent zeta potential and transparent-to-opaque change in appearance. These changes were relatively influenced by the type and the concentration of the resin used. Carbopol ® 940 and triethanolamine appeared to be superior in achieving the proposed tasks compared to other materials. The higher the pH of triethanolamine solution, the stronger the flow-modifying properties of Carbopol ® 940. Transmission electron microscopy confirmed the formation of a well-arranged gel network of Carbopol ® 940, which was the major cause for all realized changes. Later in vitro permeation studies showed a significant decrease in the drug penetration, thus further modification using 10% w/w menthol or limonene as permeation promoters was performed. This resulted in in vitro and in vivo pharmacodynamics properties that are comparably higher than the reference chosen for this study.

Fig. 2: FTIR Spectra of A: Nateglinide B: Sodium Alginate C: HPMC D: Carbopol-940 E: Nateglinide loaded microspheres made with sodium alginate F: Nateglinide loaded microspheres made with sodium alginate plus carbopo-940l G: Nateglinide loaded microspheres made with sodium alginate plus HPMC. 
Table 2 : Mean particle size, % Yield and Percentage Entrapment Efficiency of Microspheres 
Fig. 3: DSC Thermograms of A: Nateglinide, B: Sodium Alginate, C: HPMC, D: Carbopol-940, E: Nateglinide loaded microspheres made with sodium alginate, F: Nateglinide loaded microspheres made with sodium alginate plus HPMC, G: Nateglinide loaded microspheres made with sodium alginate plus carbopol-940. 
Table 3 : Micromeritics analysis of microspheres 
Table 4 : Values of correlation coefficient for the fit of various kinetic models 
Formulation and in vitro evaluation of Nateglinide microspheres using HPMC and carbopol-940 polymers by ionic gelation method

November 2013

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1,086 Reads

This study involves the design and characterization of Nateglinide (NAT) microspheres to enhance patient compliance. Ionic gelation technique was used to prepare Nateglinide Microspheres by using rate controlling polymers Carbopol-940 and Hydroxypropylmethyl cellulose (HPMC). Shape and surface were evaluated with Scanning electron microscopy (SEM). Percentage Yield, Particle size analysis, Encapsulating Efficiency, Micromeritic analysis, Fourier Transform Infra-Red Spectroscopy (FTIR), Differential Scanning Colorimetry (DSC) were done for characterization of Microspheres. Drug release studies were performed at pH 1.2 and 7.2 using USP dissolution type-II apparatus and release rates were analyzed by the application of different pharmacokinetic models. The size of microspheres was found to be varied from 781μm to 853μm. Rheological studies proved excellent flow behavior while percentage yield was found to be varied from 72% to 79%. Absence of drug-polymers interactions was confirmed from FTIR and DSC results. The microspheres prepared with sodium alginate showed cracks while microspheres obtained from blend of Carbopol-940 plus sodium alginate were smooth and spherical. Maximum entrapment efficiency (71.4%) was achieved for Microspheres with Carbopol-940. The greater retardation in drug release was observed for microspheres containing Carbopol-940 and release pattern followed Higuchi kinetics model and negligible drug release was observed at pH 1.2.

Table 1 : Four reported DMSA complexes
Fig. 2 : TLC of Tc-DMSA on TLC plate in various solvent systems. 
Fig 3 : Stability of Tc-DMSA Kits stored at various temperatures. 
Fig. 4 : Kidney uptake of 99m Tc-DMSA. 
Preparation and evaluation of (99m)Tc-DMSA lyophilized kit for renal imaging

May 2013

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1,399 Reads

Dimercaptosuccinic acid (DMSA) has been evaluated and used with technetium 99m ((99m)Tc) in imaging of kidneys. DMSA lyophilized kits were prepared and radiolabelled with (99m)Tc. Paper and thin-layer chromatography have been employed using various eluent systems for the radiochemical analysis, percentage labeling and binding capacity of (99m)Tc-DMSA. Female albino rabbits were used for this study. Biological data obtained after intravenous injection of radiolabelled DMSA to female albino rabbits revealed 32.42% uptake and long retention time in the kidneys. On the basis of animal biodistribution data, it is suggested that DMSA when labeled with (99m)Tc is useful complex for renal imaging and can be successfully applied as a diagnostic tool in nuclear medicine. Clinical biodistribution and radiation dosimetry studies are planned in future.

Table 1 : Biodistribution of 99m Tc-NHADG in Swiss Webstar mice bearing mammary carcinoma (%ID/g) b 
Scheme 1: Synthesis of N-(2-Hydroxybenzyl)-2-amino-2deoxy-D-glucose 3. Reagents: (a) salicylaldehyde; (b) NaHCO 3 ; (c) NaBH 4
Synthesis, characterization and bioevaluation of technetium-99m labeled N-(2-Hydroxybenzyl)-2-amino-2-deoxy-D-glucose as a tumor imaging agent

March 2013

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151 Reads

N-(2-Hydroxybenzyl)-2-amino-2-deoxy-D-glucose (NHADG) was synthesized by conjugation of salicylaldehyde to glucosamine. The obtained compound was well characterized via different analytical techniques. Labeling of the synthesized compound with technetium-99m (Tc) in pertechnetate form (Tc O4-) was carried out via chelation reaction in the presence of stannous chloride dihydrate. Maximum radiochemical yield of Tc-NHADG complex (99%) was obtained by using 1 mg NHADG, 200 μg SnCl.2HO, at pH 9.5 and reaction time of 15 min. The radiochemical purity of the Tc-NHADG complex was measured by Instant Thin Layer Chromatography (ITLC) and Paper Chromatography (PC), without any notable decomposition at room temperature over a period of 4h. The biological evaluation results show that the Tc labeled NHADG conjugate is able to specifically target mammary carcinoma in mice models, thus highlighting its potential as an effective Tc labeled glucose-derived agent for tumor imaging.

Fig. 1: Lymph node of dissected rabbit  
Fig. 2: Surface-modified Re 2 S 7 nanoparticles: Modification of surface through surface active thiol group by using L-cysteine ethyl ester  
In house development of (99m)Tc-Rhenium sulfide colloidal nanoparticles for sentinel lymph node detection

March 2013

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267 Reads

In this study, rhenium sulfide colloidal nanoparticles were developed as radiopharmaceutical for sentinel lymph node detection. We directly used rhenium sulfide as a starting material for the preparation of colloidal nanoparticles. UV-visible spectrophotometry was used for characterization of in house developed colloidal particles. The size distribution of radioactive particles was studied by using membrane filtration method. The percentage of radiolabeled colloidal nanoparticles was determined by paper chromatography (PC). The study also includes in vitro stability, protein binding in human blood and bioevaluation in a rabbit model. The results indicate that 77.27 ± 3.26 % particles of size less than 20nm (suitable for lymphoscintigraphy) were radiolabeled. Tc labeled rhenium sulfide labeling efficacy with the radiometal is 98.5 ± 0.5%, which remains considerably stable beyond 5h at room temperature. Furthermore, it was observed that 70.2 ± 1.3% radiolabeled colloid complex showed binding with the blood protein. Bioevaluation results show the remarkable achievement of our radiopharmaceutical. The in house prepared Tc labeled rhenium sulfide colloidal nanoparticles reached the sentinel node within 15 min of post injection. These results indicate that Tc labeled rhenium sulfide colloid nanoparticles kit produced by a novel procedure seems of significant potential as a feasible candidate for further development to be used in clinical practice.

Table 1 : 1 H-NMR data of the ligand
Fig. 2: Schematic diagram shows the probable sites of hydrolysis in the ligand thiophene-2-carboxaldehyde ethylene diamine-N-dione (A) and the technetium complex (B). The hydrolysis of (B) results in a compound of uncertain structure (C), with a vacant coordination site X, which may loosely coordinate solvent molecules.  
Fig. 3: FTIR spectra of thiophene-2-carboxaldehyde ethylene diamine-N-dione.  
Fig. 4: Structure of ligand.  
Synthesis, characterization and biodistribution of novel amine thiophene 99mTc labeled complex

April 2012

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482 Reads

(99m)Tc-labeled amine thiophene ligand might be a potential candidate for brain imaging. The purpose was to investigate the uptake of a radiolabeled drug in the brain. In this study, a tetradentate amine-thiophene-dione ligand was synthesized by the reaction of thiophene-2-carboxaldehyde with ethane-1,2-diamine and reducing with NaBH(4). The ligand system was characterized by elemental analysis, FTIR and 1H NMR. Radiolabeling of the complex with (99m)Tc was performed by reducing with stannous ions. The radiochemical purity of the radiolabeled drug was determined by paper chromatography (PC) and instant thin layer chromatography (ITLC). Bioevaluation of the (99m)Tc complex was studied in rabbits. The yield of the final product was 4.42 g (60%) and the characterization data confirmed the synthesis of the final product. The efficacy of radiolabeling was >98%. A significant uptake was observed in the brain which retained significantly upto 4h. The data indicate that the proposed system may be suitable for brain imaging in future clinical applications.

Table 1: Binding of radiometal-drug complex (%) in phosphate buffers and octanol 
Table 2 : I.D/G (injected dose per gram) of radiolabeled 99m Tc-5-flourouracil in various organs of mice
Development of 99mTc-5-fluorouracil as a potential tumor diagnostic agent

March 2013

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132 Reads

5-Fluorouracil is a well know drug for chemotherapy of various types of cancer. In the present study, we radiolabeled 5-fluorouracil with Tc for a diagnostic study of cancer. After successful labeling of the drug we performed an animal study to evaluate the potential of this radiopharmaceutical as a tumor diagnostic agent. The results showed 98.1 ± 1.2% labeling efficacy of 5-fluorouracil with Tc. The in vitro stability of the radiolabeled drug at room temperature at 4 hr of post-labeling was >96.5 ± 0.4%. The binding of the radiolabeled drug with plasma proteins was 66.6 ± 3%. Partition coefficient results showed that this drug is hydrophilic in nature. Biodistribution study in rabbit models displayed faint uptake in liver. Both kidney and bladder were prominent as excretory route of the labeled drug. Bioevaluation was performed in Swiss Webster mice having naturally developed tumor. Mice were dissected, uptake of drug in various organs was studied and results showed prominent uptake in liver and tumor. Tumor was further investigated by histopathological study.

Preparation, characterization and release of verapmil hydrochloride from polycaprolactone/acrylic acid (PCL/AA) hydrogels

October 2011

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1,040 Reads

In this study pH sensitive, biocompatible and controlled released hydrogels were prepared and their localized drug delivery effect was analyzed. Polycaprolactone and acrylic acid (PCL/AA) were reacted by free radical polymerization and developed inter penetrating polymeric network (IPN) hydrogels. Benzylperoxide was used as initiator and N, N methylenebisacrylamide [NNMBisAm] was employed as a cross-linking agent. Different concentrations of monomer, polymer and cross-linking agent were used and the reaction parameters were optimized. The obtained PCL/AA hydrogels were fully characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) that determined the polymer structure, its morphology and strength respectively. Verapamil, a calcium channel blocker was loaded by incubation of polymerization method. Controlled release Verapamil hydrogel was developed due to its low solubility; low permeability and having very short half life of 1.2-2 h. The dynamic swelling, equilibrium swelling and drug release were carried out in a buffer solution of pH 1.2, 4.5 and 6.8. Concentration of Acrylic acid showed direct, while Polycaprolactone inverse relation to swelling and drug release due to their hydrophilic and hydrophobic nature respectively. Cross-linking agent also had the contrary effect on swelling. Diffusion coefficient (D) of hydrogels was determined by using Flory-Rehner theory. Drug release and swelling data were analyzed by different kinetic models, like Zero order, First order, Higuchi, Korsmeyer's and Peppas. The release and diffusion was best described by the first order kinetics where n value was <0.5 for all the formulations indicating Fickian drug release mechanism.

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