The purpose of this study was to formulate topically effective controlled release ophthalmic acetazolamide liposomal formulations. Reverse-phase evaporation and lipid film hydration methods were used for the preparation of reverse-phase evaporation (REVs) and multilamellar (MLVs) acetazolamide liposomes consisting of egg phosphatidylcholine (PC) and cholesterol (CH) in the molar ratios of (7:2), (7:4), (7:6), and (7:7) with or without stearylamine (SA) or dicetyl phosphate (DP) as positive and negative charge inducers, respectively. The prepared liposomes were evaluated for their entrapment efficiency and in vitro release. Multilamellar liposomes entrapped greater amounts of drug than REVs liposomes. Drug loading was increased by increasing CH content as well as by inclusion of SA. Drug release rate showed an order of negatively charged > neutral > positively charged liposomes, which is the reverse of the data of drug loading efficiency. Physical stability study indicated that approximately 89%, 77%, and 69% of acetazolamide was retained in positive, negative, and neutral MLVs liposomal formulations up to a period of 3 months at 4 degrees C. The intraocular pressure (IOP)-lowering activity of selected acetazolamide liposomal formulations was determined and compared with that of plain liposomes and acetazolamide solution. Multilamellar acetazolamide liposomes revealed more prolonged effect than REVs liposomes. The positively charged and neutral liposomes exhibited greater lowering in IOP and a more prolonged effect than the negatively charged ones. The positive multilamellar liposomes composed of PC:CH:SA (7:4:1) molar ratio showed the maximal response, which reached a value of -7.8 +/- 1.04 mmHg after 3 hours of topical administration.

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The objective was to develop a microemulsion formulation for the transdermal delivery of testosterone. Microemulsion formulations were prepared using oleic acid as the oil phase, Tween20 as a surfactant, Transcutol as cosurfactant, and water. The microemulsions were characterized visually, with the polarizing microscope, and by dynamic light scattering. In addition, the pH, conductivity (sigma) and viscosity (eta) of the formulations were measured. Moreover, differential scanning calorimetry and diffusion-ordered nuclear magnetic resonance spectroscopy were used to study the formulations investigated. Conductivity measurements revealed, as a function of the weight fraction of the aqueous phase, the point at which the microemulsion made the transition from water-in-oil to bicontinuous. Alterations in the microstructure of the microemulsions, following incorporation of testosterone, have been evaluated using the same physical parameters (pH, sigma and eta) and via Fourier-transform infrared spectroscopy (FT-IR), (1)H NMR and (13)C NMR. These methods were also used to determine the location of the drug in the colloidal formulation. Finally, testosterone delivery from selected formulations was assessed across porcine skin in vitro in Franz diffusion cells. The physical parameter determinations, combined with the spectroscopic studies, demonstrated that the drug was principally located in the oily domains of the microemulsions. Testosterone was delivered successfully across the skin from the microemulsions examined, with the highest flux achieved (4.6+/-0.6microgcm(-2)h(-1)) from a formulation containing 3% (w/v) of the active drug and the composition (w/w) of 16% oleic acid, 32% Tween20, 32% Transcutol and 20% water. The microemulsions considered offer potentially useful vehicles for the transdermal delivery of testosterone.

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This research determined the uptake of individual components of topically applied microemulsions into the stratum corneum (SC) and assessed their molecular effects on skin barrier function. The microemulsions comprised oleic acid, Tween20, Transcutol and water. The effects of selected formulations, and of the individual components, on the conformational order of the SC intercellular lipids, and on SC hydration, were assessed by infrared spectroscopy. Measurements were made as a function of SC depth by progressively tape-stripping the membrane in the normal way. SC uptake of microemulsion components was quantified via extraction and analysis of the collected tape strips. SC hydration increased in proportion to the water content of the microemulsion. Each of the microemulsion components penetrated into the SC, but to different extents. Oleic acid decreased the conformational order of the SC lipids, and induced some phase separation, as revealed by the frequency shifts and peak areas of the absorbances associated with -CH(2) symmetric and asymmetric stretching vibrations. Tween20 extracted some of the SC intercellular lipids. In summary, SC structure was perturbed by all components of the microemulsions, and the degree of the effects detected was proportional to the level of the respective component present in the skin.

Background Prior acute coronary syndrome (ACS) registries in Saudi Arabia might not have accurately described the true demographics and cardiac care of patients with ACS. We aimed to evaluate the clinical characteristics, management, and outcomes of a representative sample of patients with acute myocardial infarction (AMI) in Saudi Arabia. Methods We conducted a 1-month snap-shot, prospective, multi-center registry study in 50 hospitals from various health care sectors in Saudi Arabia. We followed patients for 1 month and 1 year after hospital discharge. Patients with AMI included those with or without ST-segment elevation (STEMI or NSTEMI, respectively). This program survey will be repeated every 5 years. Results Between May 2015 and January 2017, we enrolled 2233 patients with ACS (mean age was 56 [standard deviation = 13] years; 55.6% were Saudi citizens, 85.7% were men, and 65.9% had STEMI). Coronary artery disease risk factors were high; 52.7% had diabetes mellitus and 51.2% had hypertension. Emergency Medical Services (EMS) was utilized in only 5.2% of cases. Revascularization for patients with STEMI included thrombolytic therapy (29%), primary percutaneous coronary intervention (PCI); (42.5%), neither (29%), or a pharmaco-invasive approach (3%). Non-Saudis with STEMI were less likely to undergo primary PCI compared to Saudis (35.8% vs. 48.7%; respectively, p <0.001), and women were less likely than men to achieve a door-to-balloon time of <90 min (42% vs. 65%; respectively, p = 0.003). Around half of the patients with NSTEMI did not undergo a coronary angiogram. All-cause mortality rates were 4%, 5.8%, and 8.1%, in-hospital, at 1 month, and at 1 year, respectively. These rates were significantly higher in women than in men. Conclusions There is an urgent need for primary prevention programs, improving the EMS infrastructure and utilization, and establishing organized ACS network programs. AMI care needs further improvement, particularly for women and non-Saudis.