Formulation of a topical sun protection cream for people with albinism

The aim of this investigation was to design and develop a sun protection product for people with albinism that is affordable, applicable to their specific skin condition, and provide them with the maximum sun protection possible. To achieve the required Sun Protection Factor value of > 20, simple creams were combined with very fine inorganic oxides (zinc oxide and titanium dioxide) and organic sunscreen filters (2-ethylhexyl cinnamate and octyl methoxycinnamate). These combinations also ensured high UVA/UVB protection ratios. The physical stability and change in Sun Protection Factor were for products stored for 8 weeks at 25°C (60% RH) and 45°C (75% RH) were also determined. Hypoallergenic and physically stable product(s) were formulated with SPF values between 20 to 30 and UVA/UVB ratios above 0.8 by combining simple cream formulations with fine particle inorganic oxides and organic UV protection agents. This approach offered an opportunity to formulate broad-spectrum sunscreen products that met the needs of albinos.Keywords: sun protection cream, sun protection factor, albinismThe East and Central African Journal of Pharmaceutical Sciences Vol. 7(3) 2006: 60-6

Optimal 10-aminoartemisinins with potent transmission-blocking capabilities for new artemisinin combination therapies–activities against blood stage P. falciparum including PfKI3 C580Y mutants and liver stage P. berghei parasites

We have demonstrated previously that amino-artemisinins including artemiside and artemisone in which an amino group replaces the oxygen-bearing substituents attached to C-10 of the current clinical artemisinin derivatives dihydroartemisinin (DHA), artemether and artesunate, display potent activities in vitro against the asexual blood stages of Plasmodium falciparum (Pf ). In particular, the compounds are active against late blood stage Pf gametocytes, and are strongly synergistic in combination with the redox active drug methylene blue. In order to fortify the eventual selection of optimum amino-artemisinins for development into new triple combination therapies also active against artemisinin-resistant Pf mutants, we have prepared new amino-artemisinins based on the easily accessible and inexpensive DHA-piperazine. The latter was converted into alkyl- and aryl sulfonamides, ureas and amides. These derivatives were screened together with the comparator drugs DHA and the hitherto most active amino-artemisinins artemiside and artemisone against asexual and sexual blood stages of Pf and liver stage P. berghei (Pb) sporozoites. Several of the new amino-artemisinins bearing aryl-urea and -amide groups are potently active against both asexual, and late blood stage gametocytes (IC50 0.4-1.0 nM). Although the activities are superior to those of artemiside (IC50 1.5 nM) and artemisone (IC50 42.4 nM), the latter are more active against the liver stage Pb sporozoites (IC50 artemisone 28 nM). In addition, early results indicate these compounds tend not to display reduced susceptibility against parasites bearing the Pf Kelch 13 propeller domain C580Y mutation characteristic of artemisinin-resistant Pf. Thus, the advent of the amino-artemisinins including artemiside and artemisone will enable the development of new combination therapies that by virtue of the amino-artemisinin component itself will possess intrinsic transmission-blocking capabilities and may be effective against artemisinin resistant falciparum malaria.Supplementary Table 1 | In vitro activities of selected amino-artemisinins against liver stage P. berghei, dose response curves and cytotoxicities.Supplementary Material comprises experimental details for synthesis and characterization data of the amino-artemisinins, and dose response curves for the in vitro P. berghei sporozoite stage efficacy assays recorded in Excel format in CDD Vault: UCSD CDD_Vault_Export_RESULTS_KDE_03-25-2019.This work was funded by the South African Medical Research Council (MRC) Flagship Project MALTB-Redox with funds from National Treasury under its Economic Competitiveness and Support Package to RH (MRC-RFA-UFSP-01-2013), the South African MRC Strategic Health Innovation Partnership (SHIP) grant, a South African MRC Collaborative Center for Malaria Research grant and South African National Research Foundation grants (UID 84627) to L-MB and to RH (UIDs 90682 and 98934). EW was supported by grants from the NIH (R01 AI090141-02), and Medicines for Malaria Venture, Geneva.http://www.frontiersin.org/Chemistryam2020BiochemistryGeneticsMicrobiology and Plant Patholog

Normering van vakterminologie in die Raad vir Geesteswetenskaplike Navorsing

M.A. (Linguistics)Unlike in the natural sciences, the study fields of the social sciences are closely related and large areas overlap - with regard to the use of terminology as well. However there are also differences, and in an institution such as the Human Sciences Research Council (HSRC) which comprises a heterogeneous community of subject specialists, not only the different subjects fields are represented, but also the different schools of thought (universities). In order to conduct human sciences research, the subject specialists should communicate with one another within these subject fields, but also across the borders of the different human sciences disciplines. The aim of this study was to standardize selected human sciences terminology used in the HSRC in order to provide a source of such terminology to be used mainly by HSRC personnel, and to enhance communication in this way. A theoretical review of the fields of standardization and sUbject lexicography was given. The former field was subdivided into linguistic standardization, technical language standardization and organizational standardization, and a clear organizational standardization process was distinguished on the basis of the steps of collecting, submitting, processing and distributing terminology. The field of subject lexicography concerned technical dictionaries and terminology lists, and the issue of computerizing terminology was also dealt with. The organizational standardization process with respect to HSRC terminology was explained and problematic terms identified in the study were discussed. The terminology involved in the study had been collected over a number of years by the language practitioners at the Centre for Language Services eCLS) of the HSRC, recorded on cards and later entered into the computer. In the study the terminology was submitted to the various sUbject specialists in the HSRC for their comment and approval, and their comments were subsequently researched and discussed by the CLS. The next step in the standardization process involves the processing of the comments so that the terminology can be distributed in the form of a publication or by means of a computerized database. The use of standardized terminology in the HSRC can contribute greatly towards improving communication between subject specialists and if the computerized information is transferred to the National Term Bank of the National Terminology Services as planned, the standardized HSRC terminology can be of use outside the HSRC as well

Crystallization: Its Mechanisms and Pharmaceutical Applications

The crystallization of small-molecule drugs plays an important role in the pharmaceutical industry. Since many downstream industrial processes are heavily influenced by the crystalline properties of a drug, that is, crystal shape, size distribution, and polymorphic form, control over the crystallization process can facilitate manufacturing and testing. However, before the crystallization process can be controlled, an understanding of its underlying mechanisms is required. In this chapter, we will look at the thermodynamic driving force behind crystallization and how crystal nucleation and growth rates can be used to control the properties of the resulting crystals. Throughout the chapter, we give examples of how these control approaches can be applied in pharmaceutical research and industry to obtain crystals with desired properties. We then finish this chapter with a look at crystallization from the amorphous state, which differs from crystallization from solution and is a relevant topic in pharmaceutical sciences, since the preparation of an amorphous solid is a popular approach to enhancing the solubility of a drug

The stabilization of amorphous zopiclone in an amorphous solid dispersion

Zopiclone is a poorly soluble psychotherapeutic agent. The aim of this study was to prepare and characterize an amorphous form of zopiclone as well as the characterization and performance of a stable amorphous solid dispersion. The amorphous form was prepared by the well-known method of quenchcooling of the melt. The solid dispersion was prepared by a solvent evaporation method of zopiclone, polyvinylpyrrolidone-25 (PVP-25), and methanol, followed by freeze-drying. The physico-chemical properties and stability of amorphous zopiclone and the solid dispersion was studied using differential scanning calorimetry (DSC), infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), hot-stage microscopy (HSM), X-ray diffractometry (XRD), solubility, and dissolution studies. The zopiclone amorphous solid-state form was determined to be a fragile glass; it was concluded that the stability of the amorphous form is influenced by both temperature and water. Exposure of amorphous zopiclone to moisture results in rapid transformation of the amorphous form to the crystalline dihydrated form. In comparison, the amorphous solid dispersion proved to be more stable with increased aqueous solubilityNorth-West University, South Africa (Potchefstroom Campus) as well as the National Research Foundation (NRF) of South Afric

Different amorphous solid-state forms of roxithromycin: a thermodynamic and morphological study

The striking impact that different preparation methods have on the characteristics of amorphous solidstate forms has attracted considerable attention during the last two decades. The pursuit of more extensive knowledge regarding polyamorphism therefore continues. The aim of this study was firstly, to investigate the influence of different preparation techniques to obtain amorphous solid-state forms for the same active pharmaceutical ingredient, namely roxithromycin. The preparation techniques also report on a method utilizing hot air, which although it is based on a melt intermediary step, is considered a novel preparation method. Secondly, to conduct an in-depth investigation into any physico-chemical differences between the resulting amorphous forms and thirdly, to bring our findings into context with that of previous work done, whilst simultaneously discussing a well-defined interpretation for the term polyamorphism and propose a discernment between true polyamorphism and pseudo-polyamorphism/ atypical-polyamorphism. The preparation techniques included melt, solution, and a combination of solution-mechanical disruption as intermediary steps. The resulting amorphous forms were investigated using differential scanning calorimetry, X-ray powder diffraction, hot-stage microscopy, scanning electron microscopy, and vapor sorption. Clear and significant thermodynamic differences were determined between the four amorphous forms. It was also deduced from this study that different preparation techniques have a mentionable impact on the morphological properties of the resulting amorphous roxithromycin powders. Thermodynamic properties as well as the physical characteristics of the amorphous forms greatly governed other physico-chemical properties i.e. solubility and dissolutionNational Research Foundation (NRF) of South Africa(Grant no.: TTK13020718661); Centre of Excellence for Pharmaceutical Sciences (Pharmacen) at the North-West Univer- sity Potchefstroom, South Afric