Tadalafil Nanoemulsion Mists for Treatment of Pediatric Pulmonary Hypertension via Nebulization

Oral tadalafil (TD) proved promising in treating pediatric pulmonary arterial hypertension (PAH). However, to ensure higher efficacy and reduce the systemic side effects, targeted delivery to the lungs through nebulization was proposed as an alternative approach. This poorly soluble drug was previously dissolved in nanoemulsions (NEs). However, the formulations could not resist aqueous dilution, which precluded its dilution with saline for nebulization. Thus, the current study aimed to modify the previous systems into dilutable TD-NEs and assess their suitability for a pulmonary application. In this regard, screening of various excipients was conducted to optimize the former systems; different formulations were selected and characterized in terms of physicochemical properties, nebulization performance, stability following sterilization, and biocompatibility. Results showed that the optimal system comprised of Capmul-MCM-EP:Labrafac-lipophile (1:1) (w/w) as oil, Labrasol:Poloxamer-407 (2:1) (w/w) as surfactant mixture (S_mix) and water. The optimum formulation P2_TD resisted aqueous dilution, exhibited reasonable drug loading (2.45 mg/mL) and globule size (25.04 nm), acceptable pH and viscosity for pulmonary administration, and could be aerosolized using a jet nebulizer. Moreover, P2_TD demonstrated stability following sterilization and a favorable safety profile confirmed by both in-vitro and in-vivo toxicity studies. These favorable findings make P2_TD promising for the treatment of pediatric PAH.

P–265 Investigating the nanotoxicity of solid silica nanoparticles in gametes following in vitro exposure

Study question

Do solid silica nanoparticles qualify as a new research tool for the in vitro transfer of compounds into gametes prior to Assisted Reproductive Technology (ART).

Summary answer

Solid silica nanoparticles (SSNPs) could be used as an intra-gamete delivery system to deliver therapeutic biomolecules into gametes prior to ART.

What is known already

Sperm-mediated gene transfer (SMGT) results in the production of transgenic embryos; however, the success rate of this technique is low. Nanoparticles are an efficient intra-cellular delivery system in vitro. Naturally cell-secreted nanoparticles are involved in the development of gametes. Mesoporous silica nanoparticles have been shown to carry large amounts of compounds and to interact with gametes without toxic effects, thus providing an alternative to naturally secreted nanoparticles. However, this technique is associated with some limitations, such as the size of these nanoparticles. SSNPs can be synthesised on a smaller nanoscale, thus providing higher potential to penetrate gametes and delivering biomolecules.

Study design, size, duration

This was an experimental in vitro study that investigated the effects of SSNPs on the motility of boar sperm and the degeneration of hamster oocytes, as determined by ooplasm shrinkage.

Participants/materials, setting, methods

SSNPs (20 nm) were conjugated with fluorescein diacetate–5-maleimide (FDA5M), a fluorescent protein. FDA5M-labelled SSNPS were incubated with boar sperm (N = 3) at 10 and 30µg/ml/107 sperm for four-hours. Motility parameters were assessed by computer-assisted sperm analysis (CASA). Binding potential was evaluated by fluorescent microscopy. Hamster oocytes (7 oocytes/group) were incubated with FDA5M-labelled SSNPs at 100, 150, and 300µg/ml, for two-hours; ooplasm shrinkage was evaluated. Time/matched control sperm was incubated in phosphate-buffered saline and oocytes in KSOM.

Main results and the role of chance

Exposure to FDA5M-labelled SSNPs did not affect total or progressive sperm motility (P = 0.6735 and 0.9606, respectively), average-path velocity or straight-line velocity after 4-hours of incubation (P = 0.7459 and 0.8696, respectively) compared to controls. SSNPs at 10 µg/ml significantly increased sperm curvilinear velocity after 1-hour (P = 0.0495) and linearity and straightness after 4-hours (P = 0.0389 and 0.0312, respectively). SSNPs at 30 µg/ml significantly increased sperm linearity after 3- and 4-hours (P = 0.0384 and 0.005, respectively). The proportion of sperm showing green fluorescence was significantly higher in the 30µg/ml dose of SSNPs than the 10µg/ml dose after 4-hours (P < 0.00001). In oocytes, the zona pellucida remained morphologically intact and the ooplasm exhibited green fluorescence. The ooplasm of 42% of the oocytes at 300µg/ml showed ooplasm shrinkage (a sign of degeneration); no oocytes showed shrinkage at doses of 100 and 150µg/ml of SSNPs. The green fluorescence in the sperm head and the ooplasm indicated the ability of SSNPs to spontaneously interact non-invasively with these gametes either by surface association or by cell-internalisation. This could provide a safe and non-invasive intra-gamete delivery system for research purposes and clinical therapy. This system could be used to deliver specific agents into gametes prior to ART to improve outcomes.

Limitations, reasons for caution

The SSNPs are non-biodegradable; it remains unknown as to how gametes or embryos might react with SSNPs over long time periods. The nanotoxicity of SSNPs has not yet been investigated over the long term. SSNPs have still to be tested with embryos to evaluate their effect on embryonic development.

Wider implications of the findings: SSNPs could be functionalised to target the nucleus of mammalian gametes and embryos to act as a carrier for oligonucleotides and genes to correct chromosomal abnormalities and to provide genetic therapy in these gametes and embryos to treat hereditary diseases before intra-uterine transfer.

Trial registration number

Not applicable

Community pharmacists' perceptions, awareness and practices regarding counterfeit medicines: a cross-sectional survey in Alexandria, Egypt

Background

Counterfeit medicines are a threat to public health and the national economy in Egypt. The many community pharmacists in the country could help prevent counterfeit medicines reaching the patient. Information on community pharmacists' perceptions of counterfeit medicines is lacking.

Aims

This study assessed the awareness, practices and perceptions of community pharmacists in Alexandria, Egypt with regard to counterfeit medicines. The aim was to identify gaps and inadequacies in pharmacy practice that might allow infiltration of counterfeit medicines in the legitimate medicine supply chain.

Methods

A cross-sectional study was conducted of 175 community pharmacists in Alexandria in 2014-2015. A semi-structured interview questionnaire was used to assess their perceptions, awareness and practices. The chi-squared test was used to assess the relationships between selected pharmacists' characteristics and their awareness, purchasing practice and training related to counterfeit medicines.

Results

Most pharmacists thought medicine counterfeiting was widespread in Egypt and that they could contribute to combatting the problem. However, most also lacked a clear perception of counterfeit medicines, an awareness of their danger to patients or the legislation to reduce them. Their procurement practices and detection of counterfeit medicines and handling of incidents of counterfeit medicines were inadequate. Pharmacists who thought counterfeit medicines were widespread or a health threat were significantly more likely to purchase medicines from certified sources (P < 0.05).

Conclusion

Pharmacists should be developed as a frontline resource to combat counterfeit medicines. To enhance their role, the pharmacy curriculum needs to be updated and continuing professional development activities mandated.

Intranasal Tadalafil nanoemulsions: formulation, characterization and pharmacodynamic evaluation

This study aims at improving the bioavailability of a poorly soluble phosphodiesterase-5 inhibitor; tadalafil (TD) via developing intranasal (IN) nanoemulsions (NEs). Optimum NE ingredients were selected based on solubility studies, emulsification tests, and phase diagram construction. Both o/w and w/o NEs were selected based on their drug loading capacity. Optimum formulations were subjected to physicochemical characterization and were assessed for nasal toxicity through biochemical analysis of tumor necrosis factor-α (TNF-α) and caspase-3 in rat nasal tissues. Pharmacodynamic study was performed via biochemical analysis of cyclic guanosine monophosphate (cGMP) in rat penis 2-h post-treatment and compared with oral suspension of Cialis® tablets. Optimum o/w and w/o NEs were successfully prepared using different ratios of Capmul-MCM-EP, Labrasol:Transcutol-HP (1:1) and water. Optimized formulations exhibited more than 4000-fold increase in TD solubility compared with its aqueous solubility. Both formulations were optically isotropic with the majority of globules in the nanometric-size range. Nasal toxicity study revealed no significant difference in values of TNF-α and caspase-3 between the NE-treated groups and the control group. Both TD-NEs succeeded to achieve a significant enhancement in cGMP levels. Our findings suggested that IN administration of the developed TD-NEs could provide a safe and effective alternative to TD oral delivery.

Sensitivity and Specificity Estimation for the Clinical Diagnosis of Highly Pathogenic Avian Influenza in the Egyptian Participatory Disease Surveillance Program

Many developing countries lack sufficient resources to conduct animal disease surveillance. In recent years, participatory epidemiology has been used to increase the cover and decrease the costs of surveillance. However, few diagnostic performance assessments have been carried out on participatory methods. The objective of the present study was to estimate the diagnostic performance of practitioners working for the Community-Based Animal Health and Outreach (CAHO) program, which is a participatory disease surveillance system for the detection of highly pathogenic avian influenza outbreaks in Egypt. CAHO practitioners' diagnostic assessment of inspected birds was compared with real-time reverse-transcriptase polymerase chain reaction (RRT-PCR) test results at the household level. Diagnostic performance was estimated directly from two-by-two tables using RRT-PCR as a reference test in two different scenarios. In the first scenario, only results from chickens were considered. In the second scenario, results for all poultry species were analyzed. Poultry flocks in 916 households located in 717 villages were inspected by CAHO practitioners, who collected 3458 bird samples. In the first scenario, CAHO practitioners presented sensitivity (Se) and specificity (Sp) estimates of 40% (95% confidence interval [CI]: 21%-59%) and 92% (95% CI: 91%-94%), respectively. In the second scenario, diagnostic performance estimates were Se = 47% (95% CI: 29%-65%) and Sp = 88% (95% CI: 86%-90%). A significant difference was observed only between Sp estimates (P < 0.01). Practitioners' diagnostics and RRT-PCR results were in very poor agreement with kappa values of 0.16 and 0.14 for scenarios 1 and 2, respectively. However, the use of a broad case definition, the possible presence of immunity against the virus in replacement birds, and the low prevalence observed during the survey would negatively affect the practitioners' performance.

Self-emulsifying preconcentrates of daidzein–phospholipid complex: design, in vitro and in vivo appraisal

Aim: Self-emulsifying phospholipid-complex preconcentrates (SEPPs) were fabricated to improve oral bioavailability of daidzein (DAI), an anticancer drug with challenging amphiphobic nature and extensive presystemic metabolism. Methods: DAI–phosphatidylcholine complex was prepared to enhance DAI lipophilicity and loading in SEPPs. The physicochemical characteristics and the pharmacokinetic behavior in rats were studied. Results: Surfactant-free SEPP (plain DAI:Phosal® 53MCT complex) was monodisperse upon aqueous dilution with nanorange globule size (485 ± 15 nm). Compared with drug suspension, it showed enhanced drug release and 2.38-fold enhanced oral bioavailability with minimized drug-induced intestinal irritation. Addition of 30% surfactant/co-surfactant mixture did not show any significant difference in drug release rate or absorption profile. Conclusion: The highly safe surfactant-free SEPP could be an effective approach to improve DAI oral bioavailability.

Circulation of avian influenza H5N1 in live bird markets in Egypt

The poultry meat trade in Egypt depends mainly on live bird markets (LBMs) because of insufficient slaughterhouses, lack of marketing infrastructure, and cultural preference for consumption of freshly slaughtered poultry. There are two types of LBMs in Egypt: retail shops and traditional LBMs where minimal, if any, food safety standards or veterinary inspection are implemented. Before January 2009, LBMs were considered to be a missing link in the epidemiology of avian influenza in Egypt. This incited us to initiate this surveillance to better understand the perpetuation of H5N1 and the risk of infection in poultry markets. Seventy-one out of 573 (12.4%) examined LBMs were positive for the H5N1 subtype by real-time--quantitative polymerase chain reaction (RT-qPCR) from January to April 2009. Where a 70.4% detection rate from LBMs had waterfowl only as a solitary sold species, a 26.8% detection rate from LBMs had waterfowl mixed with chicken and/or turkey, and 2.8% from LBMs had only turkey. Higher incidence, 40.8%, of positive LBMs was recorded during the cold month of February and concentrated mainly in the highly populated Nile Delta. These findings revealed wide circulation of H5N1 avian influenza virus in LBMs in Egypt, which poses a threat to public health and the poultry industry. Long-term control measures are required, and routine surveillance of bird markets should be conducted year-round.

Genetic diversity in Egyptian and Italian goat breeds measured with microsatellite polymorphism

Seven microsatellite markers were used to study genetic diversity of three Egyptian (Egyptian Baladi, Barki and Zaraibi) and two Italian (Maltese and Montefalcone) goat breeds. The microsatellites showed a high polymorphic information content (PIC) of more than 0.5 in most of the locus-breed combinations and indicated that the loci were useful in assessing within- and between-breed variability of domestic goat (Capra hircus). The expected heterozygosity of the breeds varied from 0.670 to 0.792. In the geographically wider distributed Egyptian Baladi breed there were indications for deviations from random breeding. Analysis of genetic distances and population structure grouped the three Egyptian goat breeds together, and separated them from the two Italian breeds. The studied Mediterranean breeds sampled from African and European populations seem to have differentiated from each other with only little genetic exchange between the geographically isolated populations.

Towards a universal dissolution medium for carbamazepine

The aim of this study was to develop a dissolution medium for assessment of various carbamazepine (CBZ) formulations with different strengths. The design of a system inhibiting transformation of the anhydrous CBZ (CBZ A) to the dihydrate form (CBZ D), with minimum surface-active properties and suitable sink was investigated. The effect of pH, different concentrations of sodium lauryl sulphate (SLS), polyvinylpyrrolidone (PVP), and methyl cellulose (MC) on dissolution rate, solubility, dissolution solubility, and polymorphic transformation of CBZ was assessed. Solution-mediated transformation of CBZ A into CBZ D was monitored using optical microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. Results showed that different strengths (100, 200, 400 mg) of the same CBZ tablet formulation exhibited different dissolution patterns, in 1% SLS (USP system). Such differences were reduced in 0.5% SLS solution which provided sufficient sink for up to 200 mg CBZ. It was also shown that solubility of CBZ A could not be detected in the media under study (water, SGF, SIF, and SLS solutions) due to its rapid transformation into CBZ D. The use of 3% PVP solution protected CBZ A from conversion for 75 min, while 0.01% MC completely inhibited the transformation up to 24 h. Therefore, a medium consisting of 0.5% SLS and 0.01% MC was selected. The medium provided: a) protection against transformation of CBZ A to CBZ D, b) increased solubility of CBZ A (204 mg % compared to 128 mg % of CBZ D in 0.5% SLS), c) suitable sink for up to 400 mg CBZ and d) overlapping dissolution profiles of various strengths of the same CBZ formulation. The suggested system may be a step in the way of solving CBZ dissolution problems that forced the USP to specify two similar dissolution tests with two different limits for conventional 200 mg CBZ tablets.

Study of In‐Vitro Release Characteristics of Carbamazepine Extended Release Semisolid Matrix Filled Capsules Based on Gelucires

Various extended release carbamazepine (CBZ) formulations have been developed previously, in order to reduce the frequency of dosing in chronic therapy and to decrease the variability in drug plasma concentration. In the present study, the suitability of different grades of Gelucires (G, glyceride based excipients) to formulate CBZ extended release capsules by the application of semisolid matrix (SSM) filling capsule technology was investigated. The possible modification of CBZ release kinetics by using Gelucire blends or inclusion of hydrophilic additives in the SSM was studied. The effect of ageing on some selected formulations was also evaluated, using scanning electron microscopy and differential thermal analysis. Twenty-one capsule formulations were prepared and assessed for their release characteristics. The mechanism of drug release from the test formulations was studied. The following results were obtained: a) Release data could not be correlated to the melting point (mp) of Gelucires used, pointing to relative lipophilicity of the base as a more important determinant of drug release. Among Gelucire grades having melting points higher than 37 degrees C, the release rate proved to be highly dependent on the HLB value and matrix composition. b) CBZ release occurred by different mechanisms, including matrix disintegration, diffusion and or erosion depending on the vehicle employed. c) Zero order release profiles of CBZ were obtained from SSM-based on G50/13, G53/10 and their blends in ratios higher than 1:1 and G53/10 containing croscarmellose sodium. d) The ageing study revealed that these latter formulations, except those based on G50/13, also showed high dissolution stability during one year of shelf ageing. e) PVP, as a polymorphic transformation inhibitor, can be used to reduce the storage-induced changes of some grades of Gelucires. From the above data, it can be concluded that different grades of Gelucires and their blends as well as hydrophilic additives could be successfully used to formulate CBZ extended release SSM filled capsules with various release kinetics.

Semisolid matrix filled capsules: an approach to improve dissolution stability of phenytoin sodium formulation

Seven semisolid fill bases were selected for the formulation of 24 capsule formulations, each containing 100 mg of phenytoin sodium. The fill materials were selected based on the water absorption capacity of their mixtures with phenytoin sodium. The fill matrices included lipophilic bases (castor oil, soya oil, and Gelucire (G) 33/01), amphiphilic bases (G 44/14 and Suppocire BP), and water-soluble bases (PEG 4000 and PEG 6000). The drug:base ratio was 1:2. Excipients such as lecithin, docusate sodium, and poloxamer 188 were added to some formulations. The dissolution rate study indicated that formulations containing lipophilic and amphiphilic bases showed the best release profiles. These are F4 (castor oil-1% docusate sodium); F10 (castor oil-3% poloxamer 188); F14 (G33/01-10% lecithin); F17 (G33/01-1% docusate sodium), and F20 (Suppocire BP). Further, the dissolution stability of the five formulations above was assessed by an accelerated stability study at 30 degrees C and 75% RH using standard Epanutin capsules for comparison. The study included the test and standard capsules either packed in the container of marketed Epanutin capsules (packed) or removed from their outer pack (unpacked). Release data indicated superior release rates of castor oil based formulations (F4 and F10) relative to standard capsules in both the unpacked and packed forms. For instance, the extent of drug release at 30 min after 1 month was 91% for F4 and F10 and 20% for standard capsules. Drug release from packed capsules after 6 months storage was 88% for both formulations F4 and F10 and 35% for standard capsules. In conclusion, the pharmaceutical quality of phenytoin sodium capsules can be improved by using a semisolid lipophilic matrix filled in hard gelatin capsules.

Infections in children under 5 years old and latrine cleanliness

The aim of this study is to assess the cleanliness of the latrine and its relation to occurrence of disease in children under 5 years old. A stratified random sample of 1327 households was conducted in 11 villages in Upper Egypt. It included a sub-sample of 541 children under 5 years living in households with latrines. The latrine cleanliness was assessed and its relationship to disease occurrence within a period of 2 weeks. Thirty-three percent (33.1%) of children under 5 years old with latrines in their household had infections, compared to 28.3% of those without latrines in the house. Infection with diarrhoea was found most in houses with latrine and water tap. A relation was found between latrine cleanliness score and presence of flies, house building material and maternal education, but none with occurrence of infection in children under 5 years old within a period of 2 weeks.

Study of serum copper and zinc in cases of hyperemesis gravidarum

The dehydration, electrolyte and metabolic changes which occur in hyperemesis gravidarum are well recognized. The aim of this paper was to study the changes in serum copper and zinc and their correlation with the changes in serum electrolytes that occur in patients with hyperemesis gravidarum. Serum copper, zinc, sodium and potassium and urinary chloride were measured in 30 patients suffering from hyperemesis gravidarum and compared to the levels in 10 normal pregnant women in their first trimester. There was no significant change in serum copper or zinc in patients with hyperemesis compared to normal pregnant women. Also, there was no significant correlation between the changes in the level of these trace elements and the decrease which occurred in serum sodium and potassium and urinary chloride.

Effect of aspirin on gastric acid secretion in the rat

The effects of aspirin on gastric acid and sodium have been studied in a perfused rat stomach preparation. In the pentagastrin-stimulated stomach, as intraluminal aspirin concentration increased, there was a significant fall in acid output together with a significant decrease in the loss of sodium from the gastric lumen. It was concluded that these observations were due to a back-diffusion effect resulting from disruption of the gastric mucosal barrier rather than parietal cell inhibition