Therapeutic Efficacy of Great Plantain (Plantago major L.) in the Treatment of Second-Degree Burn Wounds: A Case-Control Study

BACKGROUND

Great plantain (Plantago major L. or P.major) is a medicinal plant that is available all around the world. The whole plant has several bioactive compounds including terpenoids, flavonoids, phenolic compounds, alkaloids, fatty acids, iridoid glycosides, polysaccharides, and vitamins. Scientific studies have recognized several medical benefits like wound healing, anti-inflammatory, antimicrobial, antiulcerative, and antioxidative agents. The wound-healing capacity of this plant has been investigated under in vivo and ex vivo conditions. In the current study, we aim to compare the therapeutic effect of the P.major extract with 1% sulfadiazine on the healing of second-degree burn wounds.

METHOD

Second-degree burn victims were included in our study. The investigation and control group, respectively, received P. major ointment 10% and silver sulfadiazine ointment 1%. The bacterial culture from the wound site was taken on days 3, 7, 10, 13, and last day of hospitalization. Patients' subjective complaints were obtained through the visual analog scale (VAS). All patients were treated and evaluated in the hospital.

RESULT

Among the 15 patients, 11 were male, and the mean age was 33.3 years. The average complete healing duration was 11.73 vs. 13 days in the P. major and control group, respectively (P=0.166). On the third day, infection control was similar between the two groups, and on the seventh day, all bacterial cultures were negative. Although there was a significant reduction in pain scores during the recovery time, no significant differences in pain reduction were noted between the two groups (P=0.849).

CONCLUSION

We showed that P.major ointment is a safe and suitable herbal compound in the treatment of second-degree burn wounds that not only has wound-healing properties but also is an analgesic and antimicrobial compound.

An Evidence-Based Review on Medicinal Value of Clays in Traditional Persian Medicine

The use of earths and clays for medical purposes dates back to antiquity. In recent years, there has been an increasing interest in researches on traditional remedies in the hope of discovering new drug. Iran is an ancient country with a medical backbone acquired from the experiences of ancient Persian scholars, who had made a great contribution to the development of the medical sciences. Many medical and pharmaceutical books by early Persian scientists still exist and may have the potential of leading researchers to new drug discoveries. Owing to the emergence of new and antimicrobial-resistant infections, present-day medicine has recently begun focusing on medicinal earths and clays especially as mineral antimicrobials. The current study is, therefore, aimed at gathering information regarding medicinal clays in traditional Persian medicine (TPM). Five main Persian materia medica with the key word 'tin' (clay) and current databases such as PubMed, Scopus, ScienceDirect, and Google Scholar were searched by key words 'white, green, red, maroon, violet, black, grey and pink clays' and 'pharmacological effects'. Twenty three clays were found in Persian manuscripts. Although their mineralogical compositions are unknown, different pharmacological properties have been attributed to these mineral medicaments. Clay's properties were widely used in medieval times for the treatment of infections to poisoning. They were also used in compound formulations, possibly for their pharmaceutical formulation modifying effects. Modern scientific proofs have also been found in many of the medicinal clays reported in Persian manuscripts. Although many of the reported clays are still unknown, their characterization may lead to new medicinal developments. Novel analytical methods available today make it possible to elucidate the chemical compositions of these minerals as parameters responsible for their medicinal effects.

Nicotinamide loaded functionalized solid lipid nanoparticles improves cognition in Alzheimer's disease animal model by reducing Tau hyperphosphorylation

BACKGROUND

Nicotinamide is considered to be effective in halting the Alzheimer's disease progression. The body could absorb a limited amount of nicotinamide at a time, requiring multiple doses through a day. To overcome such an obstacle which reduces the patient compliance, a sustained/controlled delivery system could be useful.

METHOD

Nicotinamide loaded solid lipid nanoparticles (SLN) were prepared and functionalized with polysorbate 80 (S80), phosphatidylserine (PS) or phosphatidic acid (PA). The acquired particles were characterized and evaluated in respect of their cytotoxicity, biodistribution, and in vivo effectiveness through the different routes of administration.

RESULTS

The optimum sizes of 112 ± 1.6 nm, 124 ± 0.8 nm, and 137 ± 1.05 nm were acquired for S80-, PS-, and PA-functionalized SLNs, respectively. The in vitro cytotoxicity on SH-SY5Y cell line showed the safety of formulations except for S80-functionalized SLNs. Biodistribution study of SLNs has proved the benefits of functionalization in improving the brain delivery. The results of spatial and memory test, i.e. Morris water maze, and also histopathology and biochemical tests demonstrated the effectiveness of i.p. injection of PS -functionalized SLNs in improving the cognition, preserving the neuronal cells and reducing tau hyperphosphorylation in a rat model of Alzheimer's disease.

CONCLUSION

The acquired PS-functionalized SLN could be a potential brain delivery system. Loaded with nicotinamide, an HDAC inhibitor, it could ameliorate the cognition impairment of rats more effectively than the conventional administration of nicotinamide, i.e. oral, in the early stage of Alzheimer's disease. Graphical abstract ᅟ.

Application of Response Surface Method for Preparation, Optimization, and Characterization of Nicotinamide Loaded Solid Lipid Nanoparticles

Purpose: Solid lipid nanoparticles (SLNs) have been proven to possess pharmaceutical advantages. They have the ability to deliver hydrophilic drugs through lipid membranes of the body. However, the loading of such drugs into SLNs is challenging. Hydrophilic nicotinamide, a histone deacetylase inhibitor, is used to establish SLNs with enhanced encapsulation efficiency by using statistical design.

Methods: The possible effective parameters of these particles’ characteristics were determined using pre-formulation studies and preliminary tests. Afterwards, the Response Surface Method (RSM) was utilized to optimize the preparation condition of SLNs. The effect of the amount of lipid, drug, surfactant, and the mixing apparatus were studied on particle size, zeta potential, and encapsulation efficiency of the obtained particles. The acquired particles were characterized in respect of their morphology, in vitro release profile, and cytotoxicity.

Results: According to this study, all the dependant variables could be fitted into quadratic models. Particles of 107 nm with zeta potential of about -40.9 and encapsulation efficiency of about 36% were obtained under optimized preparation conditions; i.e. with stearic acid to phospholipon® 90G ratio of 7.5 and nicotinamide to sodium taurocholate ratio of 14.74 using probe sonication. The validation test confirmed the model’s suitability. The release profile demonstrated the controlled release profile following the initial burst release. Neither the nicotinamide nor the SLNs showed toxicity under the evaluated concentrations.

Conclusion: The acquired results suggested the suitability of the model for designing the delivery system with a highly encapsulated water soluble drug for controlling its delivery.

Aqueous Concentration of Tranexamic Acid after 5% and 10% Eyedrop Administration

Purpose

To determine whether topical tranexamic acid can provide acceptable therapeutic concentration in the aqueous humor.

Methods

A total of 47 patients with cataract as the sole eye disease who have been scheduled for cataract operation received one drop of tranexamic acid 5% solution at various time intervals prior to operation (from 15 minutes to 9 hours). Two patients received 10% solution of the drug. Paracentesis of the anterior chamber was done and the aqueous humor was aspirated in the operation room. The aqueous samples were analyzed using high-performance liquid chromatography method with the limit of quantification around 0.1 μg/mL. Systemic and ocular side effects were evaluated.

Results

Aqueous concentrations of tranexamic acid was higher than 1.5 μg/mL up to 160 minutes after administration of a single drop of 5% solution of the drug and then declined to an average concentration of 1 μg/mL at 300 minutes which persisted up to 9 hours after administration. In two patients for whom a single drop of 10% tranexamic acid solution was used, aqueous concentrations of 2.72 and 2.90 μg/mL were detected 60 minutes after administration. None of the patients experienced ocular or systemic side effects.

Conclusions

Topical administration of tranexamic acid is effective in yielding therapeutic intraocular concentrations of drug without any ocular or systemic toxicity.

Observational Study of Associations between Voriconazole Therapeutic Drug Monitoring, Toxicity, and Outcome in Liver Transplant Patients

The aim of this study was to investigate the variability of the voriconazole plasma level and its relationships with clinical outcomes and adverse events among liver transplant recipients to optimize the efficacy and safety of their treatment. Liver transplant recipients treated with voriconazole were included, and voriconazole trough levels were quantified by a validated high-performance liquid chromatography method. Cytochrome P450 genotypes for CYP2C19 were evaluated in allograft liver tissues. A total of 832 voriconazole trough levels from 104 patients were measured. Proven, probable, and possible invasive fungal infections were reported for 8/104 (7.7%), 42/104 (40.4%), and 54/104 (51.9%) patients, respectively. Receiver operating characteristic (ROC) curve analysis indicated that trough concentrations of ≥1.3 μg/ml minimized the incidence of treatment failure (95% confidence interval [CI], 0.68 to 0.91 μg/ml) (P < 0.001) and that those of <5.3 μg/ml minimized the incidence of any adverse events (95% CI, 0.83 to 0.97 μg/ml) (P < 0.001). Voriconazole trough levels were significantly higher for heterozygous extensive metabolizers, poor metabolizers, and individuals receiving coadministration with proton pump inhibitors. For ultrarapid metabolizers, oral administration of voriconazole, and concomitant use of glucocorticoids, voriconazole blood concentrations were significantly reduced. Furthermore, there was no statistically significant association of patient age, weight, or gender or coadministration of tacrolimus and cyclosporine with the voriconazole trough level. In conclusion, the results of our analysis indicate large inter- and intraindividual variabilities of voriconazole concentrations in liver transplant recipients. Voriconazole trough concentrations of ≥1.3 μg/ml and <5.3 μg/ml are optimal for treatment and for minimization of adverse events. Optimization of drug efficacy and safety requires the use of rational doses for voriconazole therapy.

Development, evaluation and optimization of superparamagnetite nanoparticles prepared by co-precipitation method

Magnetic nanoparticles (MNPs) are of high interest due to their application in medical fields, in particular for theranostics. Specific properties required for such particles include high magnetization, appropriate size and stability. Biocompatible magnetically soft magnetite particles (Fe₃O₄) have been investigated for biological purposes. The intrinsic instability of these nanoparticles and their susceptibility to the oxidization in air, are limitations for their applications. Various methods have been described for synthesis of these nanoparticles among which co-precipitation method is widely experimented. In order to illustrate the synthesis of MNPs elaborately, the effect of different factors on particle formation were studied. The particles morphology, stability, paramagnetic effect, chemical structure and cytotoxicity were evaluated. Particles of 58 and 60 nm obtained by oleic acid coated (OMNPs) and citric acid coated (CMNPs) magnetite nanoparticles respectively. Transmission electron microscopy images exhibited the real sizes are 15 and 13 nm. Magnetic saturations of these nanoparticles were 72 and 68 emu/g which is suitable for medical applications. Both OMNPs and CMNPs were non-toxic to the SK-Br-3 and MCF-7 cells in the concentrations of <2.5 μg/mL. Since these particles exhibit relatively high magnetic saturation, low dose of such material would be required; therefore, these NPs seem to be suitable for theranostics.

Nanoparticles of Chitosan Loaded Ciprofloxacin: Fabrication and Antimicrobial Activity

Purpose: Chitosan is a natural mucoadhesive polymer with antibacterial activity. In the present study, chitosan (CS) nanoparticles were investigated as a vehicle for delivery of antibiotic, ciprofloxacin hydrochloride. Methods: Ionotropic gelation method was used for preparation chitosan nanoparticles. The effects of various factors including concentration of CS, concentration of tripolyphosphate (TPP), and homogenization rate on the size of nanoparticles were studied. The effects of various mass ratios of CS to ciprofloxacin hydrochloride on the encapsulation efficiency of nanoparticles were assessed. Results: The particles prepared under optimal condition of 0.45% CS concentration, 0.45% TPP concentration and homogenizer rate at 6000 rpm, had 72 nm diameter. In these particles with 1:0.5 mass ratio of CS to ciprofloxacin hydrochloride, the encapsulation efficiency was 23%. The antibacterial activity of chitosan nanoparticles and ciprofloxacin-loaded nanoparticles against E.coli and S.aureus was evaluated by calculation of minimum inhibitory concentration (MIC). Results showed that MIC of ciprofloxacin loaded chitosan nanoparticles was 50% lower than that of ciprofloxacin hydrochloride alone in both of microorganism species. Nanoparticles without drug exhibited antibacterial activity at higher concentrations and MIC of them against E.coli and S.aureus was 177 and 277 µg/ml, respectively. Conclusion: Therefore chitosan nanoparticles could be applied as carrier for decreasing the dose of antibacterial agents in the infections.

Inhalable, large porous PLGA microparticles loaded with paclitaxel: preparation, in vitro and in vivo characterization

Large porous particles (LPPs) could be used as a useful carrier for non-invasive delivery to the deep lung. Pulmonary delivery of paclitaxel-loaded LPPs (PTX-LPPs) can help to eliminate the highly complicated and harmful solvent used in PTX parenteral formulations. PTX-LPPs with mass median aerodynamic diameter (MMAD) of 5.74 ± 0.09 μm, high encapsulation efficiency and good aerosolisation properties were produced using ammonium bicarbonate as porogen. Cytotoxicity of PTX-LPPs on A549 and Calu-6 cell lines was comparable with Free-PTX. Endotracheal administration of PTX-LPPs in rats exhibited PTX plasma concentration in the therapeutic range which lasted 4-fold longer than i.v. injection. The bioavailability was measured as 51 ± 7.1%. The lung targeting efficiency (Te) of PTX-LPPs was 11.9-fold higher than i.v. administration. PTX-LPPs could deliver a higher PTX to lung with a non-toxic plasma level in a longer duration which shows their pulmonary delivery suitability.

A Randomized Double Blind Clinical Trial on a Sabgh Formulation for Patients With Vitiligo

BACKGROUND

The cosmetic problem that vitiligo produces affects patients psychologically. Many patients with vitiligo are suggested to cover their white skin patches with cosmetic products. There are formulations in traditional Iranian pharmacy to color these white skin patches. In this study, one of these formulations was compared with a cosmetic formulation.

METHODS

Two groups of patients were selected. One group used a marketed formulation and other group used a traditional Iranian Pharmacy formulation. The quality of life of the patients was compared based on the Dermatology Life Quality Index Questionnaire.

RESULTS

Both interventions were associated with statistically improved Dermatology Life Quality Index scores over the 8-week intervention (P < .05), although the difference between the 2 was not statistically significant (P = .436).

CONCLUSION

Traditional Iranian Pharmacy formulation is effective in increasing the quality of life in vitiligo patients.

Armenian bole: a historical medicinal clay

The medical use of earths and minerals is probably as old as the history of mankind. Particular types of clays and earths are still being used worldwide as therapeutic agents in the folk medicine of different countries. From the 19th century, the medicaments included in countries' pharmacopeias whose exact pharmacological activity or the chemistry of their active components was not known gradually decreased in number, despite their popularity among patients. With today's analytical armamentarium it may be time to reconsider returning some of those compounds to pharmacopeias. By using modern techniques in the past two decades, researchers have studied the active components of healing clays and their pharmacological properties. Many of them possess valuable therapeutic properties which could be used in modern medicine in pharmaceutical dosage forms. Our knowledge about the medical substances that our ancestors used through centuries could be used today as an evidence base for further clinical and pharmacological research. One of these substances is Armenian bole. In this work we studied the historical perspective of its therapeutic use in different countries. Also a sample sold in the market in Iran was purchased and X-ray diffraction analysis was performed on it to find out its chemical composition.

Olfactory stimulation by vanillin prevents apnea in premature newborn infants

OBJECTIVE

Apnea is one of the most common problems in premature newborns. The present study aimed to determine the effect of olfactory stimulation by vanillin on prevention of apnea in premature newborns.

METHODS

In this randomized controlled trial, 36 premature newborns with the postnatal age of 2 days and weight under 2500 grams referred to the hospitals affiliated to Shiraz University of Medical Sciences, were selected through simple random sampling and allocated into control and experimental groups. The experimental group received olfactory stimulation by saturated vanillin solution, while the control group received no interventions. The newborns of both groups were continuously monitored for presence/absence of apnea and number of episodes of apnea as well as arterial blood oxygen saturation and heart rate for 5 days. The data were analyzed by independent Student t-test and repeat measure ANCOVA.

FINDINGS

The presence of apnea revealed to be significantly different between the two groups in the first, second, and fourth day of the study (P<0.05). The number of episodes of apnea during five days was also significantly different between the study groups (t=8.32, P<0.05). Using olfactory stimulation by vanillin caused a 3.1-fold decrease in apnea and the effect size was 0.72. Moreover, the two groups were significantly different regarding the arterial blood oxygen and heart rate during the study period (P<0.05).

CONCLUSION

This study indicated the beneficial effect of saturated vanillin solution on apnea; therefore, it may be used for prevention and treatment of apnea in premature infants. Further studies are needed to improve evidence-based practice in this regard.

Preparation and in-vitro characterization of tramadol-loaded carrier erythrocytes for long-term intravenous delivery

Objectives

The hypo-osmotic dialysis method was used for preparation of tramadol-loaded human intact erythrocytes. In response to rapid drug escape from the erythrocytes, a membrane cross-linker, glutaraldehyde, was used successfully.

Methods

The resulting carrier cells were validated in terms of the accuracy and precision of the whole drug loading procedure.

Key findings

The average loaded amount, entrapment efficiency and cell recovery were 1.9041 mg, 95.98% and 85.13%, respectively. The effects of different drug concentrations on loading parameters were studied with the concentration of 10 mg/ml selected as optimal. A series of in-vitro characteristics of carrier erythrocytes, including tramadol release behaviour, haematological indices, particle size distribution, scanning electron microscopy, and osmotic/turbulence fragilities were determined compared with the sham-entrapped and unloaded cells. The results of these in-vitro tests indicated that the erythrocytes did not undergo remarkable irreversible size and shape/topology changes, but the fragility of the membranes of the processed cells were increased.

Conclusions

The collective results of this study showed that the optimized method of entrapment was suitable for the encapsulation of tramadol in erythrocytes with the final carrier cells ready to enter the in-vivo animal studies as a promising long-circulating carrier for tramadol.

The effects of some permeability enhancers on the percutaneous absorption of lidocaine

Local anesthesia of the intact skin is difficult because of the barrier properties of skin to epicutaneous penetration of local anesthetic drugs. Using local anesthetics with combination of penetration enhancers could overcome this problem. The main objective of this study was to assess the effects of some permeability enhancers on the percutaneous permeation of lidocaine. The effect of polysorbate 80, polysorbate 20, dimethylsulfoxide (DMSO), tert-butyl cyclohexanol (TBCH), and alpha-terpinol in different concentrations and various ratios of lidocaine to enhancers was evaluated. The results showed that polysorbate 80 and polysorbate 20 has no detectable penetration enhancing effects in guinea pig skin mounted to diffusion cells. The same results were obtained to water/oil ratio and the type of oil phase (liquid paraffin vs. castor oil). Addition of DMSO to the previous formulations had a considerable enhancing effect. According to the data, the extent of lidocaine permeation was proportional to the concentration of DMSO in these formulations. The best results belonged to the addition of terpenes but interestingly there wasn't any linear relationship between the concentrations of alpha- terpinol/ or TBCH and the duration of antinociceptive effects of lidocaine. Based on the results of this study the ratio of 1: 4 from alpha- terpinol or TBCH to lidocaine results in a better antinociceptive effect and alpha- terpinol was the best one among of these compounds. This effect was proven with in vivo tail- immersion test to assess the antinociceptive effect of formulations which have shown more penetration.

The effect of polymer blends on release profiles of diclofenac sodium from matrices

The purpose of this study was to evaluate the effect of polymer blends on the in vitro release profile of diclofenac sodium. Several controlled release matrices of diclofenac sodium with different proportions of hydroxypropyl methylcellulose (HPMC; viscosity grade 60 and 500 mPa.s), carbopol 940 and lactose as a water soluble filler were prepared. The results showed that when HPMC (viscosity grade 60 mPa.s) alone was used as matrix former, diclofenac sodium was released fast but the release rate became slower with HPMC (viscosity grade 500 mPa.s) at higher polymer/drug ratios (more than 0.8:1). However in lower polymer/drug ratios (lower than 0.7:1) the release rate still was fast. The results showed that carbopol can extend the release time appreciably but the release profiles had considerable fluctuations, and drug release in first hours was slow but increased appreciably with time at the end of profiles. When an appropriate blend of HPMC (viscosity grade 60 or 500 mPa.s) and carbopol 940 was used, the drug release became more uniform and its kinetic approached to zero order and release fluctuations were diminished. The results with these polymer blends showed that it is possible to reduce the total amounts of polymer in each formulation. According to kinetic analysis data, drug release from these matrix tablets did not follow Fick's law of diffusion and the results were in agreement with the earlier reports.

In vitro and in vivo activities of syn2836, syn2869, syn2903, and syn2921: new series of triazole antifungal agents

The in vitro and in vivo activities of four azole compounds belonging to a new series of 2(2,4-difluorophenyl)-3-(4-substituted piperazin-1-yl)-1-(1,2,4-triazol-1-yl) butanol antifungal agents is described. The compounds were selected from a library of azole compounds synthesized by our group. The in vitro activities of Syn2869, Syn2836, Syn2903, and Syn2921 against a panel of over 240 recently collected clinical isolates of yeast and molds were determined, and the results were compared with those obtained with fluconazole (FLC), itraconazole (ITC), and amphotericin B (AMB). The MICs at which 90% of the isolates were inhibited (MIC(90)s) for the four test compounds for strains of Candida spp. ranged from <0.048 to 0.78 microg/ml. All compounds were also active against FLC-resistant Candida albicans and other Candida sp. strains. Moreover, MIC(90)s for strains of Cryptococcus neoformans, Aspergillus spp., Trichophyton spp., and Microsporum spp. were also low and ranged from <0.048 to 0.39 microg/ml. The test compounds produced a fungistatic pattern during the time-kill kinetic studies. In vivo studies indicated that all four test compounds have good efficacies against C. albicans in a murine systemic infection model and significantly improved the survival rates of the infected mice. The results for Syn2903 were similar to those for FLC, while the other compounds were slightly less effective but had ranges of activities similar to the range of activity of ITC. The compounds were also evaluated against an Aspergillus fumigatus systemic infection. Syn2903 was also superior to ITC, whereas the efficacy data for the other compounds were similar to those for ITC. It was concluded from the data generated for this new series of azole compounds in the studies described above that further pharmacokinetic and toxicologic evaluations are warranted prior to selection of a candidate compound for preclinical testing.

High-performance liquid chromatographic assay for the determination of novel triazole antifungal agents in tissue. Application to tissue distribution studies

A simple and rugged reversed-phase high-performance liquid chromatographic method with ultraviolet absorbance detection at 263 nm was developed and validated for the analysis of novel triazole antifungal agents SYN-2869 and its derivatives in tissues. The method involved homogenization with 0.01 M phosphate buffer (pH 7.8) for lung, brain and spleen tissues. The liver and kidneys were homogenized with acetonitrile:acetone (1:1). The plasma proteins were precipitated with ice-cold acetonitrile and supernatent was evaporated to dryness. The reconstituted samples were injected onto an HPLC system. SYN-2869 was separated from the matrix components on a symmetry C(18) column using a aqueous mobile phase of acetonitrile and water with a flow rate of 1 mL/min. A step gradient of 40-80% acetonitrile eluted SYN-2869 and the internal standard (SYN-2506). The linear range was 0.5-10 microgram/g (r(2) > 0.99). The limit of quantitation was 0.5 microgram/g. The inter-day precision and accuracy for SYN 2869 standard concentration were from 2.6 to 7.4% and from -1.56 to +3.29%, respectively. The method was applied to tissue samples collected from single intravenous administration to mice to evaluate the distribution of these novel antifungal agents to different tissues.

Interspecies comparison of pharmacokinetics of the novel triazole antifungal agent SYN-2869 and its derivatives

The pharmacokinetics and distribution in tissue of several novel triazole antifungal agents were studied in different animal species in order to select an appropriate lead compound. The purpose of the study was also to determine species differences in pharmacokinetics for SYN azoles to select the most appropriate species for secondary efficacy and toxicological evaluation of the selected compound. SYN-2836, SYN-2869, SYN-2903, and SYN-2921 were rapidly absorbed into the systemic circulation and reached maximum concentrations (C(max)s) of 7.31 +/- 2.53, 6.29 +/- 0.85, 6.16 +/- 0.39, and 3.41 +/- 0.34 microg/ml, respectively, in BALB/c mice after administration of an oral dose of 50 mg/kg of body weight, with bioavailability being greater than 45% in all mice. The areas under the concentration-time curve from time zero to infinity (AUC(0-infinity)s) after administration of a single intravenous dose of 20 mg/kg to mice varied between 25.0 and 63.6 microg. h/ml. The half-life was in the range of 4.5 to 6 h. In Sprague-Dawley rats there was no significant difference in AUC(0-infinity) after administration of a single intravenous dose of 20 mg/kg, but on oral administration, the bioavailability of SYN-2836 was extremely low, while that of SYN-2869 was only 14.7%. In New Zealand White rabbits the C(max) and the time to reach C(max) for SYN-2836 and SYN-2869 after administration of a single oral dose of 50 mg/kg were similar. There were significant differences in AUC(0-infinity) and half-life between SYN-2836 and SYN-2869. On the other hand, in beagle dogs the C(max) and AUC(0-infinity) of SYN-2836 after administration of a single oral dose of 30 mg/kg were 4.82 +/- 1.54 microg/ml and 41.8 +/- 15.7 microg. h/ml, respectively, which were threefold higher than those of SYN-2869. The concentrations of the SYN compounds in tissue indicated that the AUC(0-infinity)s of SYN-2836, SYN-2869, SYN-2903, and SYN-2921 in mouse lungs were significantly different from each other. The ratios of the concentrations of the SYN azoles in lungs to those in plasma were also significantly different from those for itraconazole. Among the SYN azoles the highest concentration in the lungs was found for SYN-2869. The higher level of distribution of SYN-2869 into lung tissue was considered to contribute to the potent efficacy in respiratory tract infection models compared with the potency of itraconazole. Significant differences in the pharmacokinetics of these compounds were observed in different animal species, and selection of an animal model for further evaluation was based on results obtained from these studies.

High-performance liquid chromatographic analysis of new triazole antifungal agent SYN-2869 and its derivatives in plasma

A simple reversed-phase high-performance liquid chromatography (HPLC) method with UV detection was developed and validated for the quantitation of SYN-2869, a novel triazole antifungal agent and its analogs in rat plasma. The method involved a simple precipitation of plasma protein with acetonitrile (1:10 ratio). The reconstituted sample after evaporation to dryness was injected onto a HPLC column. SYN-2869 and its analogs were separated from the matrix components on a symmetry C18 column using an aqueous mobile phase of acetonitrile and water with a flow rate of 1 ml min(-1). A step gradient of 40-80% acetonitrile eluted all four compounds. The run time was 30 min. The linear range was 0.5 10 microg ml(-1)(r2 > 0.999). The limit of quantitation was 0.5 microg ml(-1). The inter-day precision and accuracy for SYN-2869 standard concentration were from 1.9 to 8.5% and from 1.4 to +/- 4.40%, respectively. The precision and accuracy of intra-day quality control samples were from 4.6 to 5.2% and from 4.6 to 12%, respectively.

Biopharmaceutical evaluation of a tablet dosage form made from ethyl cellulose encapsulated aspirin particles

Ethyl cellulose encapsulated aspirin particles, suitable for preparation of direct compression tablets were prepared by the solvent evaporation method. Ethyl acetate was used as a solvent for the polymer in combination with a saturated solution of aspirin as the dispersing medium to prevent partitioning and drug loss. This resulted in a high yield of free-flowing, non-aggregated particles. In vitro-in vivo evaluations of the experimental aspirin tablets (made by direct compression of ethyl cellulose encapsulated particles) and three different commercial aspirin products (a conventional tablet, a timed-release tablet, and a timed-release caplet) were undertaken. Comparison of the dissolution in acidic media at pH 1.2 showed different release profiles for these products. While the conventional tablet and the timed-release caplet showed the highest and the lowest rate of release, respectively; the timed-release tablet and the experimentally made tablet revealed an intermediate rate and very similar release profiles. The cumulative urinary excretion data collected in a complete crossover study, using five healthy subjects further indicated that the experimental tablet has an in vivo availability identical to that of the timed-release tablet.