All about Pharmacognosy

All about Pharmacognosy

Archive for November, 2011

The preventive effect of N-butanol fraction of Nigella sativa on ethylene glycol-induced kidney calculi in rats

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Mousa-Al-Reza Hadjzadeh, Abolfazl Khajavi Rad, Ziba Rajaei, Maryam Tehranipour, Nahid Monavar

Pharmacognosy Magazine 2011 7(28):338-343

Background: The current study was carried out to determine whether the aqueous-ethanolic extract or the butanolic fraction of Nigella sativa (NS) seeds could prevent or reduce calculi aggregation in experimental calcium oxalate nephrolithiasis in Wistar rats. Materials and Methods: Male Wistar rats were randomly divided into 5 groups: group A received tap drinking water for 28 days. Groups B, C, D and E received 1% ethylene glycol for induction of calcium oxalate (CaOx) calculus formation for 28 days. Rats in groups C, D and E also received aqueous-ethanolic extract of NS, N-butanol fraction and N-butanol phase remnant of NS, respectively, in drinking water at a dose of 250 mg/kg for 28 days. Urine concentration of oxalate, citrate, and calcium on days 0, 14, and 28, and also serum concentration of magnesium and calcium on days 0 and 28, were measured. On day 29, kidneys were removed for histopathologic study and examined for counting the calcium oxalate deposits in 10 microscopic fields. Result: Treatment of rats with N-butanol fraction and N-butanol phase remnant of NS significantly reduced the number and size of kidney calcium oxalate deposits compared with ethylene glycol group. Urinary concentration of oxalate in all experimental groups increased compared with control group on days 14 and 28, whereas the urine citrate concentration was lower in all experimental groups compared with control group on days 14 and 28. Conclusion: N-butanol fraction and N-butanol phase remnant of NS showed a beneficial effect on calcium oxalate deposition in the rat kidney. Therefore, the butanolic fraction of NS may be suggested for prevention of calcium oxalate calculi in humans.

Written by Mousa-Al-Reza Hadjzadeh

November 30th, 2011 at 12:00 am

Determination of 5-hydroxymethyl-2-furaldehyde of crude and processed fructus corni in freely moving rats using in vivo microdialysis sampling and liquid chromatography

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Enhong Ouyang, Chengrong Zhang, Xiaomeng Li

Pharmacognosy Magazine 2011 7(28):271-276

Background: Fructus Corni is derived from the dry ripe sarcocarp of Cornus officinalis Sieb. et Zucc. 5-hydroxymethyl-2-furaldehyde (5-HMF) is an important active composition of the Fructus Corni. However, there have been no reports on the concentration of 5-HMF in freely moving rats using microdialysis coupled with HPLC. Materials and Methods: The concentration of 5-HMF in free-moving rats after intra-gastric (i.g.) administration of the water extract of Fructus Corni and JZP was analyzed by microdialysis coupled with high-performance liquid chromatographic (HPLC). Results: Results demonstrated that the concentration of 5-HMF in microdialysate was 1.4951 μg/l, but higher in rat microdialysate after i.g. administration of the aqueous extract of JZP (5.2662 μg/l). Conclusion: This method is proved to be rapid, accurate and simple. Real-time in vivo monitoring the concentration of 5-HMF provides the theoretical basis for further explaining the processing mechanism of Fructus Corni.

Written by Enhong Ouyang

November 30th, 2011 at 12:00 am

Antioxidative effects of cinnamomi cortex: A potential role of iNOS and COX-II

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Jin-Won Chung, Jeong-Jun Kim, Sung-Jin Kim

Pharmacognosy Magazine 2011 7(28):314-319

Background: Cinnamomi cortex has wide varieties of pharmacological actions such as anti-inflammatory action, anti-platelet aggregation, and improving blood circulation. In this study, we tested to determine whether the Cinnamomi cortex extract has antioxidant activities. Materials and Methods: Antioxidative actions were explored by measuring free radical scavenging activity, NO levels, and reducing power. The mechanism of antioxidative action of Cinnamomi cortex was determined by measuring iNOS and COX-II expression in lipopolysaccharide (LPS) stimulated Raw cells. Results: Seventy percent methanolic extract of Cinnamomi cortex exerted significant 1,1-diphenyl–2–picrylhydrazyl (DPPH) free radicals and NO scavenging activities in a dose-dependent manner. More strikingly, the Cinnamomi cortex extract exerted dramatic reducing power activity (13-fold over control). Production of iNOS induced by LPS was significantly inhibited by the Cinnamomi cortex extract, suggesting that it inhibits NO production by suppressing iNOS expression. Additionally, COX-2 induced by LPS was dramatically inhibited by the Cinnamomi cortex extract. Conclusion: These results suggest that 70% methanolic extract of Cinnamomi cortex exerts significant antioxidant activity via inhibiting iNOS and COX-II induction.

Written by Jin-Won Chung

November 30th, 2011 at 12:00 am

Is statistical significance a relevant tool for assessing clinical significance?

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Syed Wasif Gillani

Journal of Pharmaceutical Negative Results 2011 2(2):121-122

Written by Syed Wasif Gillani

November 25th, 2011 at 12:00 am

Design and one-pot synthesis of new α-aminophosphonates and antimicrobial activity

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Zahra Rezaei, Soghra Khabnadideh, Younes Ghasemi, Masomeh Fadaei, Zeinab Karimi

Journal of Pharmaceutical Negative Results 2011 2(2):78-86

Background: α-Aminophosphonates are bioisosters of amino acids and have several pharmacological effects. α-Aminophosphonates have been synthesized by various routes from reaction between an amine, an aldehyde, and phosphate compounds.
Materials and Methods: We synthesized 20 new α-aminophosphonates in the presence of FeCl3 in THF as a catalyst to facilitate the Manich-type reaction of aldehyde, amine and phosphite compounds to form the corresponding α-aminophosphonates in a one-pot, three-component reaction. In this study, the catalytic effect of ZnCl2 was also compared with FeCl3 in the synthesis of α-aminophosphonates. Results: The results showed that FeCl3 catalyzed the reaction in mild conditions to form α-aminophosphonates with high yields, but ZnCl2 did not give high yields of the compounds and the reaction took longer time in comparison to that taken by FeCl3 The chemical structures of all new compounds were confirmed by spectrophotometric methods (1HNMR, 13CNMR, IR). The compounds were investigated for antimicrobial activity against Escherichia coli, Bacillus subtilis, Salmonella typhi, Shigella sonnei, Proteus vulgaris, and Staphylococcus epidermidis. Conclusion: The new synthesized compounds did not show good antibacterial activity against the tested microorganisms

Written by Zahra Rezaei

November 25th, 2011 at 12:00 am

Insignificant difference between biofilm forming isolates of filtered water and non-filtered water

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Sangita Revdiwala, Summaiya Mulla, Nrupal Chevli

Journal of Pharmaceutical Negative Results 2011 2(2):110-114

Aim: Biofilm formation is a developmental process with intercellular signals that regulate growth. Biofilms contaminate catheters, ventilators, and medical implants; they act as a source of disease for humans, animals, and plants. In this study we have done a quantitative assessment of biofilm formation in bacterial isolates, associated with the drinking water distribution system, in tryptic soya broth, with different incubation times. Materials and Methods: The study was carried out on 104 samples of water from different systems. The bacterial isolates were processed as per the microtiter plate method with only tryptic soya broth, and with varying concentrations of glucose, and were observed in response to time. Results: Out of the total of 104 samples of water, 63 were found to be bacteriologically positive and 24 of them were biofilm formers. Enterobacter spp. and Pseudomonas were maximally found to be biofilm producing. Conclusion: Biofilm formation depends on adherence of bacteria to various surfaces. Overhead plastic tanks and metal taps were the most common sources being infected. We must have a regular policy to get them clean so as to have affordable and safe drinking water.

Written by Sangita Revdiwala

November 25th, 2011 at 12:00 am

Antacids incorporation in immediate release tablets failed to improve the stability of omeprazole in acidic media

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HV Chavda, TM Chaudhary, CN Patel

Journal of Pharmaceutical Negative Results 2011 2(2):73-77

Background: The stability of omeprazole (OMZ) decreases in acidic medium. In this investigation, attempts have been made to develop oral tablet containing antacids/buffers to increase the pH of dissolution media for certain time. Materials and Methods: Tablet formulations were prepared by the direct compression technique. For the selection of superdisintegrant, Croscarmellose sodium, used initially was replaced with other superdisintegrants. The prepared tablets were evaluated for hardness, weight variation, thickness, friability, drug content, disintegration time and in vitro drug release studies. During the in vitro drug release studies, the pH of dissolution media was measured. Results and Discussion: All batches showed very short disintegration time, within 0.5-2 min except F1 and S5. Batch F7 was able to provide the immediate drug release. The study showed that the incorporation of antacid improved the pH of dissolution media, but failed to maintain it. Even though the high quantities of antacids were incorporated; the stability of drug in media was not improved. Other superdisintegrants did not show any significant changes in drug release or disintegration time. Bath F7 was stable for the period of 6 months at 40 o C / 75 %RH. Conclusions: Incorporation of higher quantities of antacids failed to retain the stability of OMZ in acidic media.

Written by HV Chavda

November 25th, 2011 at 12:00 am

Sodium nitrite therapy fails to improve tissue perfusion in a mouse model of hind limb ischemia: Slight differences in methodology may be responsible casting suspicion on the reliability and predictive value of this model

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Jeff S McKee, Benjamin D Brooks

Journal of Pharmaceutical Negative Results 2011 2(2):99-106

Background: The nude mouse model of hind limb ischemia is used to evaluate human-derived, cell-based therapeutics intended to promote tissue perfusion. The criticism of the mouse model of hind limb ischemia is the absence of a well-characterized positive control. The suitability of sodium nitrite (NaNO 2 ) was evaluated. The rationale for doing so was based on a report that NaNO 2 induced unprecedented tissue perfusion in wild-type mice using a similar model. The objective was to evaluate NaNO 2 to improve tissue perfusion in nude mice as well as their wild-type counterparts. Materials and Methods: The mice underwent surgically induced, unilateral hind limb ischemia, and received either NaNO 2 or a vehicle intraperitoneally, twice daily, for seven days. Hind limb tissue perfusion was evaluated on days one, four, seven, and fourteen post-surgery. Results: No increase in tissue perfusion was observed in the nude or wild-type mice treated with NaNO 2 when compared with the vehicle. Nude mice exhibited significantly lower tissue perfusion compared to wild-type mice, irrespective of the treatment. Conclusions: NaNO 2 failed to increase tissue perfusion and, therefore, did not appear suitable for use as a positive control in this model. This is in stark contrast to a previous report indicating that NaNO 2 significantly increased tissue perfusion in wild-type mice using a similar model. The exact cause is not known, but is probably due to differences in methodology employed between laboratories. The lower tissue perfusion in nude mice is a novel finding, suggesting this strain may have less pre-existing collateral vessels and/or a reduced capacity to form new vessels as compared to wild-type mice.

Written by Jeff S McKee

November 25th, 2011 at 12:00 am

Effort toward the single pot synthesis of 6-(Biphenyl-4-yl)-2-[2-(indol-1-yl)ethyl]-4,5-dihydropyridazin-3(2H)-one from 6-(Biphenyl-4-yl)-2-[2-(indol-1-yl)ethyl]-4,5-dihydropyridazin-3(2H)-one

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Mohammad Asif, Anita Singh, Lakshmayya

Journal of Pharmaceutical Negative Results 2011 2(2):69-72

Background: Many synthetic heterocyclic compounds are known to have different biological activities. Pyridazine and its derivatives are the important six membered heterocyclic compounds containing two N-hetero atoms. The pyridazine moiety is an important structural feature of many biologically active compounds. Pyridazine derivatives show diverse pharmacological properties. Aims and Objectives of the Study: The goal of this study, Pyridazine hold considerable interest relative to the preparation of organic intermediates and physiologically active compounds also. On the basis of its important in reported literature, we synthesized the 6-(Biphenyl-4-yl)-2-[2-(indol-1-yl)ethyl]-4,5-dihydropyridazin-3(2H)-one from 6-(Biphenyl-4-yl)-2-[2-(indol-1-yl)ethyl]-4,5-dihydro pyridazin-3(2H)-one in single step or pot reaction. Results : The important Observations and concrete implications of the study. The result showed that the compound 6-(Biphenyl-4-yl)-2-[2-(indol-1-yl) ethyl]-4,5-dihydropyridazin-3(2H)-one was not prepared by this method. The synthesis of compound has been confirmed by the spectral analysis namely IR, 1H NMR and Mass spectroscopy.

Written by Mohammad Asif

November 25th, 2011 at 12:00 am

Reporting of sample size and power in negative clinical trials published in Indian medical journals

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Jaykaran , Preeti Yadav, ND Kantharia

Journal of Pharmaceutical Negative Results 2011 2(2):87-90

Background and Aim: It is observed that negative clinical trials published in medical journals are poor in reporting of sample size calculation, various components of calculation of sample size. It is also observed that they are underpowered to detect the actual difference between the treatment outcomes. Because of scarcity of these data for Indian medical journals we designed this study to critically analyze the Indian medical journals for reporting of sample size, components of sample size and power. We calculated post hoc power for 30% and 50% difference between the treatment outcomes. Materials and Methods: All the negative clinical trials published in five Indian medical journals (Indian Journal of Pharmacology (IJP), Indian Pediatrics (IP), Indian Journal of Dermatology (IJD), Indian Journal of Dermatology, Vanereology and Leprology (IJDVL), and Journal of Postgraduate Medicine (JPGM)), between 2001 and 2008, were analyzed by each author for reporting of the sample size and components of the sample size. Post hoc power for 30% and 50% differences between the outcome was calculated by G Power software. All data were expressed as frequency, percentages, and 95% confidence interval around the percentages with the help of SPSS ver. 17. Results: The median sample size was observed to be 33 (range 9-85). Power was calculated in 28 (41.1%, 95% CI 30.2% to 53%) trials. The sample size was not calculated in 34 (50%, 95% CI 38.4% to 61.5%) trials. The full sample size was calculated in only 2 (2.9%, 95% CI 0.8% to 10.1%) trials. Post hoc power above 80% for 30% of difference was reported in 3 (4.4%, 95% CI 1.5% to 12%) trials and for 50% difference in outcome it was reported in 42 (61.7%, 95% CI 49.8% to 72.3) trials. Conclusion: Negative clinical trials published in five Indian journals are poor in reporting of sample size calculation. It is also observed that most of trials are underpowered to see the 30% and 50% difference between the outcomes. There is a need to generate more awareness regarding the sample size and power calculation

Written by Jaykaran

November 25th, 2011 at 12:00 am

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