Assessment of penetration of Ascorbyl Tetraisopalmitate into biological membranes by molecular dynamics

The present work, involves the simulation of the transport of a vitamin C derivative, Ascorbyl Tetraisopalmitate (ATI), through human skin by molecular dynamics. Percutaneous absorption of the ATI molecule through the infundibulum, an important route of absorption into the hair follicle of the human skin, has been modeled and compared with the stratum corneum membrane. The comparative study was done, using molecular dynamics with Martini force field. In infundibulum, a single ATI molecule require more time to penetrate, and the data obtained suggested that a high concentration of ATI molecule accelerated the process of penetration. In conclusion, the ATI molecule was found to have more affinity towards the stratum corneum as compared towards the infundibulum and it followed a straight pathway to penetrate (until 600 ns of simulation). In infundibulum, it showed less affinity, more mobility and followed a lateral pathway. Thus, this work contributes to a better understanding of the different molecular interactions during percutaneous absorption of active molecules in these two different types of biological membranes.The authors acknowledge financial support from the Brazilian agencies CAPES, Finep and Fapesp (Project FINEP 01.10.0661-00, FAPESP 2011/13250-0, FAPESP 2013/17247-9, FAPESP 2014/05975-2, CAPES 88887068264/2014-00), of Institute of Research and Development, University of Vale Paraíba

Lipid nanoparticles loaded with iridoid glycosides: development and optimization using experimental factorial design

Lipid nanoparticles based on multiple emulsion (W/O/W) systems are suitable for incorporating hydrophilic active substances, including iridoid glycosides. This study involved optimization of composition of lipid nanoparticles, incorporation of active compounds (aucubin and catalpol), evaluation of stability of the resulting nanocarriers, and characterization of their lipid matrix. Based on 32 factorial design, an optimized dispersion of lipid nanoparticles (solid lipid:surfactant4.5:1.0 wt.%) was developed, predisposed for the incorporation of iridoid glycosides by emulsification-sonication method. The encapsulation efficiency of the active substances was determined at nearly 90% (aucubin) and 77% (catalpol). Regarding the stability study, room temperature was found to be the most suitable for maintaining the expected physicochemical parameter values (particle size |± 30 mV|). Characterization of the lipid matrix confirmed the nanometer size range of the resulting carriers (below 100 nm), as well as the presence of the lipid in the stable form.M.D. wishes to acknowledge the Erasmus+ programme for financial support in the organization of traineeship at the University of Coimbra, Portugal.info:eu-repo/semantics/publishedVersio

Cancer incidence and mortality in Greater Poland Province in 2006 – Report

Greater Poland is a region of high cancer risk in Poland. Standardized rates for cancer incidence among man and woman are the highest in Poland. Standardized rates for cancer deaths are also very high (4th place for men and 2nd for woman).When analysing the absolute numbers of cases and deaths among men in Greater Poland for last eight years, we observe increase of cases number by 16,14% and deaths by 10,85%.Most common cancer incidence sites in Greater Poland for man are: lung, colorectum and prostate. Among woman breast, colorectum and lung.Most common cancer deaths sites in men are: lung, colorectum and stomach. Among woman breast, lung and colorectum.When analysing standardized rates for malignant tumors morbidity and mortality among men and women, we see clearly that increase of number of new cancer cases and deaths is determined first of all by ageing in Greater Poland population.Lung cancer in Greater Poland is situated in first three most common cancer sites by incidence and mortality. Region has a medium lung cancer incidence and mortality compare to other voivodships. In analyzed period (1999–2006) lung cancer incidence and mortality among men has decreased. Unfortunately the same trend is not observed among women.High breast cancer incidence is very typical for Greater Poland. Analysis of standardized rates shows that Greater Poland is on 3rd place by breast cancer incidence and on the 4th place by breast cancer mortality. The most important and at the same time the cheapest method to eliminate tumors is prophylactics and screening

Comparing the delivery to the hair bulb of two fluorescent molecules of distinct hydrophilicities by different nanoparticles and a serum formulation

The follicular route is an important drug penetration pathway in any topical application, either concerning dermatological and cosmetic skin treatments or any transdermal administration regimen. Efficient transport into follicles will depend on drug inherent properties but also on the chosen vehicle. The main study goal was to compare several systems for the delivery to the hair bulb of two fluorescent molecules of different water affinities: the hydrophobic Nile Red and the quite similar but hydrophilic Nile Blue. Three common nanoparticle types were compared in terms of encapsulation efficiency and stability: liposomes, ethosomes and polymeric nanoparticles. A liquid serum-like formulation was also developed, adjusting the final ethanol amount to the type of dye to be solubilized. Then, this formulation and the nanoparticle systems that successfully passed characterization and stability stages were further studied on their ability to reach the bulb. The serum formulation was able to deliver, both drug models, to deeper follicular regions than nanoparticles. Attending to the envisioned zone target of the follicle, the simplest approach proved to be the best choice from all the systems tested in this work. Nonetheless, nanocarriers and the inherent complexity of their manufacturing processes may be justified under very specific requirements.The author Cristiana Costa would like to acknowledge his PhD scholarship funded by Portuguese Foundation for Science and Technology (FCT) (SFRH/BD/139522/2018). The author Bruno Fernandes would like to acknowledge his PhD scholarship funded by FCT (SFRH/BD/131824/2017). The author Diana Guimarães would like to acknowledge his PhD scholarship funded by FCT (SFRH/BD/140321/2018). This study was supported by the FCT under the scope of BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Mikro- i nanocząstki lipidowe jako nośniki roksytromycyny do mieszków włosowych

promotor: Krzysztof Cal

Collagen and Its Derivatives Serving Biomedical Purposes: A Review

Biomaterials have been the subject of extensive research, and their applications in medicine and pharmacy are expanding rapidly. Collagen and its derivatives stand out as valuable biomaterials due to their high biocompatibility, biodegradability, and lack of toxicity and immunogenicity. This review comprehensively examines collagen from various sources, its extraction and processing methods, and its structural and functional properties. Preserving the native state of collagen is crucial for maintaining its beneficial characteristics. The challenges associated with chemically modifying collagen to tailor its properties for specific clinical needs are also addressed. The review discusses various collagen-based biomaterials, including solutions, hydrogels, powders, sponges, scaffolds, and thin films. These materials have broad applications in regenerative medicine, tissue engineering, drug delivery, and wound healing. Additionally, the review highlights current research trends related to collagen and its derivatives. These trends may significantly influence future developments, such as using collagen-based bioinks for 3D bioprinting or exploring new collagen nanoparticle preparation methods and drug delivery systems