Carbomer Hydrogels with Microencapsulated α-Tocopherol: Focus on the Biocompatibility of the Microcapsules, Topical Application Attributes, and In Vitro Release Study.

The microencapsulation of α-tocopherol based on the complex coacervation of low-molecular-weight chitosan (LMWC) and sodium lauryl ether sulphate (SLES) without harmful crosslinkers can provide biocompatible carriers that protect it from photodegradation and air oxidation. In this study, the influence of the microcapsule wall composition on carrier performance, compatibility with a high-water-content vehicle for topical application, and release of α-tocopherol were investigated. Although the absence of aldehyde crosslinkers decreased the encapsulation efficiency of α-tocopherol (~70%), the variation in the LMWC/SLES mass ratio (2:1 or 1:1) had no significant effect on the moisture content and microcapsule size. The prepared microcapsule-loaded carbomer hydrogels were soft semisolids with pseudoplastic flow behavior. The integrity of microcapsules embedded in the hydrogel was confirmed by light microscopy. The microcapsules reduced the pH, apparent viscosity, and hysteresis area of the hydrogels, while increasing their spreading ability on a flat inert surface and dispersion rate in artificial sweat. The in vitro release of α-tocopherol from crosslinker-free microcapsule-loaded hydrogels was diffusion-controlled. The release profile was influenced by the LMWC/SLES mass ratio, apparent viscosity, type of synthetic membrane, and acceptor medium composition. Better data quality for the model-independent analysis was achieved when a cellulose nitrate membrane and ethyl alcohol 60% w/w as acceptor medium were used.

Development of Lipid-Based Gastroretentive Delivery System for Gentian Extract by Double Emulsion-Melt Dispersion Technique.

Gentian (Gentiana lutea L., Gentianaceae) root extract (GRE) is used for the treatment of gastrointestinal disorders. However, its bioactive potential is limited in conventional forms due to the low bioavailability and short elimination half-life of the dominant bioactive compound, gentiopicroside. The aim of study was to encapsulate GRE in the lipid-based gastroretentive delivery system that could provide high yield and encapsulation efficiency, as well as the biphasic release of gentiopicroside from the tablets obtained by direct compression. Solid lipid microparticles (SLM) loaded with GRE were prepared by freeze-drying double (W/O/W) emulsions, which were obtained by a multiple emulsion-melt dispersion technique, with GRE as the inner water phase, Gelucire® 39/01 or 43/01, as lipid components, with or without the addition of porous silica (Sylysia® 350) in the outer water phase. Formulated SLM powders were examined by SEM and mercury intrusion porosimetry, as well as by determination of yield, encapsulation efficiency, and flow properties. Furthermore, in vitro dissolution of gentiopicroside, the size of the dispersed systems, mechanical properties, and mucoadhesion of tablets obtained by direct compression were investigated. The results have revealed that SLM with the macroporous structure were formulated, and, consequently, the powders floated immediately in the acidic medium. Formulation with porous silica (Sylysia® 350) and Gelucire® 43/01 as a solid lipid was characterized with the high yield end encapsulation efficiency. Furthermore, the mucoadhesive properties of tablets obtained by direct compression of that formulation, as well as the biphasic release of gentiopicroside, presence of nanoassociates in dissolution medium, and optimal mechanical properties indicated that a promising lipid-based gastroretentive system for GRE was developed.

Chitosan/Sodium Dodecyl Sulfate Complexes for Microencapsulation of Vitamin E and Its Release Profile-Understanding the Effect of Anionic Surfactant.

Microencapsulation of bioactive substances is a common strategy for their protection and release rate control. The use of chitosan (Ch) is particularly promising due to its abundance, biocompatibility, and interaction with anionic surfactants to form complexes of different characteristics with relevance for use in microcapsule wall design. In this study, Ch/sodium dodecyl sulfate (SDS) microcapsules, without and with cross-linking agent (formaldehyde (FA) or glutaraldehyde (GA)), were obtained by the spray drying of vitamin E loaded oil-in-water emulsion. All of the microcapsules had good stability during the drying process. Depending on the composition, their product yield, moisture content, and encapsulation efficiency varied between 11-34%, 1.14-1.62%, and 94-126%, respectively. SEM and FTIR analysis results indicate that SDS as well as cross-linkers significantly affected the microcapsule wall properties. The profiles of in vitro vitamin E release from the investigated microcapsules fit with the Korsmeyer-Peppas model (r2 > 0.9). The chemical structure of the anionic surfactant was found to have a significant effect on the vitamin E release mechanism. Ch/SDS coacervates may build a microcapsule wall without toxic crosslinkers. This enabled the combined diffusion/swelling based release mechanism of the encapsulated lipophilic substance, which can be considered favorable for utilization in food and pharmaceutical products.

Study of vitamin E microencapsulation and controlled release from chitosan/sodium lauryl ether sulfate microcapsules.

Potential benefit of microencapsulation is its ability to deliver and protect incorporated ingredients such as vitamin E. Microcapsule wall properties can be changed by adding of coss-linking agents that are usually considered toxic for application. The microcapsules were prepared by a spray-drying technique using coacervation method, by depositing the coacervate formed in the mixture of chitosan and sodium lauryl ether sulfate to the oil/water interface. All obtained microcapsules suspensions had slightly lower mean diameter compared to the starting emulsion (6.85 ± 0.213 µm), which shows their good stability during the drying process. The choice and absence of cross-linking agents had influence on kinetics of vitamin E release. Encapsulation efficiency of microcapsules without cross-linking agent was 73.17 ± 0.64 %. This study avoided the use of aldehydes as cross-linking agents and found that chitosan/SLES complex can be used as wall material for the microencapsulation of hydrophobic active molecules in cosmetic industry.

Progress of the Journal of the Balkan Union of Oncology in the second decade of its existence.

PURPOSE: To investigate the progress of the Journal of the Balkan Union of Oncology (JBUON) in the second decade of its existence. METHODS: We investigated 10 volumes of JBUON, consisting of 42 issues, with regard to the number and category of articles, the contribution of authors from Balkan and non-Balkan countries, and the (co)authorship in published articles. RESULTS: In period 2006-2015, 1407 articles of different categories were published in JBUON. Most were original articles. In 2009, JBUON became listed in Science Citation Index (SCI) database and gained impact factor (IF). After that, the values of some investigated parameters (e.g. submission rate, total number of papers and the number of original articles) correlated with constant rise of the IF value. CONCLUSION: During the second decade of JBUON the journal has been gradually progressing in regard to the submission rate, the percentage of original papers, contribution of more countries other than Balkan countries, and the number of authors per article. This progress is the consequence of indexing in the SCI list in 2009, and to steadily rise of the IF value.

Importance of being indexed in important databases--effect on the quantity of published articles in JBUON.

PURPOSE: To investigate the dynamics of indexing the Journal of the Balkan Union of Oncology (JBUON) in important biomedical databases, the effects on the quantity and type of published articles, and also the countries of the (co)authors of these papers. METHODS: The process of the JBUON indexing started with EMBASE/Excerpta Medica, followed in 2006 (PUBMED/MEDLINE) and continued every second year in other important biomedical databases, until 2012 when JBUON became Open Access Journal (for even more information please visit www.jbuon.com). Including the next two years for monitoring the effect of the last indexing, we analyzed 9 volumes consisting of 36 issues that were published from January 2006 to December 2014, with regard to the number and category of articles, the contribution of authors from Balkan and non-Balkan countries, and the (co)authorship in the published articles. RESULTS: In the period 2006-2014, 1165 articles of different categories were published in J BUON. The indexing progress of JBUON immediately increased the submission rate, and enlarged the number of publications, original papers in particular, in every volume of JBUON. Authors from Balkan countries contributed in 80.7% of all articles. The average number of coauthors per original article grew slowly and was higher at the end of the investigated period than at the start (6.6 and 5.8, respectively). CONCLUSION: The progressing covering of JBUON in important biomedical databases and its visibility on international level attracted the attention of a large readership, and submission rate and the number of published articles grew significantly, particularly the number of original papers. This is the most important consequence of the editorial policy which will hopefully lead to even more progress of JBUON in the near future.

Multiauthorship and false authorship: why worrying about this?

Authorship and authorship abuse are in the focus of interest of all main actors in the publication game--authors, reviewers and editors of scientific journals. Along with the steady rise of the number of publications, the number of coauthors in multiauthored papers raises even more, some of them being undeserved authors. Because publication is the main way for evaluating scientists, authorship is prone to abuse, and thus the false/undeserved/gift authorship emerges. This dilutes the responsibility and damages the publication enterprise, thus initiating a constant struggle of scientific community against this type of scientific dishonesty. In this paper, several prevention and corrective measures with the aim to diminish such a dishonest behavior of authors are described.

Effects of a short-term differently dosed aerobic exercise on maximum aerobic capacity in breast cancer survivors: a pilot study.

BACKGROUND/AIM: Regular physical activity and exercise improves quality of life and possibly reduces risk of disease relapse and prolongs survival in breast cancer survivors. The aim of this study was to evaluate the impact of a 3-week moderate intensity aerobic training, on aerobic capacity (VO2max) in breast cancer survivors. METHODS: A prospective, randomized clinical study included 18 female breast cancer survivors in stage I-IIIA, in which the primary treatment was accomplished at least 3 months before the study inclusion. In all the patients VO2max was estimated using the Astrand's protocol on a bicycle-ergometer (before and after 3 weeks of training), while subjective assessment of exertion during training were estimated by the Category-Ratio RPE Scale. Each workout lasted 21 minutes: 3 minutes for warm-up and cool-down each and 15 min of full training, 2 times a week. The workload in the group E1 was predefined at the level of 45% to 65% of individual VO2max, and in the group E2 it was based on subjective evaluation of exertion, at the level marked 4-6. Data on the subjective feeling of exertion were collected after each training course in both groups. RESULTS: We recorded a statistically significant improvement in VO2max in both groups (E1--11.86%; E2--17.72%), with no significant differences between the groups. The workload level, determined by the percent of VO2max, was different between the groups E1 and E2 (50.47 +/- 7.02% vs 55.58 +/- 9.58%), as well as subjective perception of exertion (in the groups E1 and E2, 11.6% and 41.6% of training, respectively, was graded in the mark 6). CONCLUSION: In our group of breast cancer survivors, a 3-week moderate intensity aerobic training significantly improved the level of VO2max.

[Fraud in biomedical literature].

The basic ethical principles in science are internationally recognised in all disciplines of science. The first among these is honesty--both towards oneself and towards others. The betrayal of this principle can be seen as deviant behaviour, which may result in the most serious violation of the high ethical standards of science--scientific fraud. Fraudulent behaviour in biomedical sciences is particularly damaging, since all diagnostic and treatment decisions are based on what is published in medical literature. The betrayers of science undermine, to a great extent, the public trust in science, and may destroy the confidence scientists have in each other as well, which is a grave danger to science itself. In this article, several high profile cases of scientific fraud--involving falsification, fabrication of data, and plagiarism--are described. The damaging effect they had on both science and the scientific community led to the codification of the concept of Good Scientific Practice (GSP)--an international quality standard for designing, conducting, recording, and reporting research. The concept of GSP sets internationally valid benchmarks for quality assurance, and also provides safeguards against scientific dishonesty and fraud.