The development of biocompatible composite materials is in high demand in many fields such as biomedicine, bioengineering, and biotechnology. In this study, two series of poly (D,L-lactide) and poly (ε-caprolactone)-based films filled with neat and modified with poly (glutamic acid) (PGlu) nanocrystalline cellulose (NCC) were prepared. An analysis of scanning electron and atomic force microscopies’ results shows that the modification of NCC with poly (glutamic acid) favored the better distribution of the nanofiller in the polymer matrix. Investigating the ability of the developed materials to attract and retain calcium ions led to the conclusion that composites containing NCC modified with PGlu induced better mineralization from model solutions than composites containing neat NCC. Moreover, compared to unmodified NCC, functionalization with PGlu improved the mechanical properties of composite films. The subcutaneous implantation of these composite materials into the backs of rats and the further histological investigation of neighboring tissues revealed the better biocompatibility of polyester materials filled with NCC–PGlu.

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The manufacturing of modern scaffolds with customized geometry and personalization has become possible due to the three‐dimensional (3D) printing technique. A novel type of 3D‐printed scaffolds for bone tissue regeneration based on poly(ε‐caprolactone) (PCL) filled with nanocrystalline cellulose modified by poly(glutamic acid) (PGlu‐NCC) has been proposed in this study. The 3D printing set‐ups were optimized in order to obtain homogeneous porous scaffolds. Both polymer composites and manufactured 3D scaffolds have demonstrated mechanical properties suitable for a human trabecular bone. Compression moduli were in the range of 334–396 MPa for non‐porous PCL and PCL‐based composites, and 101–122 MPa for porous scaffolds made of the same materials. In vitro mineralization study with the use of human mesenchymal stem cells (hMSCs) revealed the larger Ca deposits on the surface of PCL/PGlu‐NCC composite scaffolds. Implantation of the developed 3D scaffolds into femur of the rabbits was carried out to observe close and delayed effects. The histological analysis showed the lowest content of immune cells and thin fibrous capsule, revealing low toxicity of the PCL/PGlu‐NCC scaffolds seeded with rabbit MSCs (rMSCs) to the surrounding tissues. The most pronounced result on the generation of new bone tissue after implantation of PCL/PGlu‐NCC + rMSCs scaffolds was detected by both microcomputed tomography and histological analysis. Around 33% and 55% of bone coverage were detected for composite 3D scaffolds with adhered rMSCs after 1 and 3 months of implantation, respectively. This achievement can be a result of synergistic effect of PGlu, which attracts calcium ions, and stem cells with osteogenic potential.

Проведен анализ статистических показателей заболеваемости туберкулезом различных локализаций в Российской Федерации за 2001-2016 гг. с акцентом на гендерные и возрастные особенности. Показано влияние ВИЧ-инфекции на уровень заболеваемости туберкулезом. Приведены и обобщены данные о внелегочных локализациях специфического процесса, дано описание сложностей их официальной регистрации, ограничивающих достоверность эпидемиологического анализа, и представлена расчетная картина заболеваемости.