Location of Pulmonary Mycobacteria Tuberculosis and Effectiveness of Various Dextrazide Compositions in Treatment of Mice with BCG-Induced Granulomatosis.

The study examined effectiveness of liposomal form of dextrazide (inhaled or intraperitoneal), free dextrazide (intraperitoneal), and isoniazid (intraperitoneal) in the treatment of BALB/c mice with BCG-induced granulomatosis. The mice were infected with mycobacteria tuberculosis 3 months prior to onset of treatment. The preparations under examinations were administered twice a week over 2 months. The decrease of the number and size of macrophagal granulomas in mice BCG-induced granulomatosis during treatment was determined by the number of living mycobacteria tuberculosis in these granulomas. The most effective treatment was achieved with liposomal form of dextrazide (a conjugate of oxidized dextran with isonicotinic acid hydrazide). Macrophages with captured mycobacteria tuberculosis, dextrazide, and dextrazide-loaded liposomes can be incorporated into granulomas. The antimycobacterial effect of dextrazide is an important factor preventing the destructive processes in granulomas and organs via a decrease in the prodestructive potential of lysosomes in macrophages realized after their migration from granulomas.

Efficacy of Inhalations of Antituberculous Compositions with Different Length of Experimental Therapy Course in Mice.

The study compared antituberculous efficacy of individual or combined administration of "free" isoniazid and liposomal form of dextrazide (a composition consisted of isoniazid and oxidized dextran) inhaled in standard (15 mg/kg) or low (3 mg/kg) dose. The therapy started 1 month after contamination of outbred ICR male mice with Mycobacterium tuberculosis strain H37Rv. Combined inhalation of liposomal form of dextrazide and isoniazid in the low dose was most effective against mycobacterium tuberculosis due to diminished prodestructive pulmonary effect and a low hepatotoxicity. A minor prodestructive effect of this combination was observed starting from 1.5 month after the onset of therapy (12 inhalations, 2 times a week), and it augmented after 24 inhalations administered during 3 months.

Chemical Reprogramming of Somatic Cells in Neural Direction: Myth or Reality?

In in vitro experiments on cultures of human multipotent stem cells from the human bonearrow and dental pulp, we studied direct reprogramming towards neuro-glial lineage cells using a cocktail of small molecules. Reprogramming by the previously published protocol (with a cocktail containing ß-mercaptoethanol, LIF, VPA, CHIR99021, and RepSox) and by the optimized protocol (VPA, RG108, А83-01, dorsomorphin, thiazovivin, CHIR99021, forskolin, and Isx9) allows obtaining cells with immunophenotypic and genetic signs of neural stem cells. However, neither the former, nor the optimized protocols allowed preparing neural progenitors capable of adequate terminal differentiation from both bone marrow-derived mesenchymal stem cells and nestin-positive neural crest-derived mesenchymal stem cells. Real-time PCR demonstrated the expression of some neurogenesis markers, but neural stem cell-specific expression pattern was not observed. The findings lead us to a conclusion that reprogramming with small molecules without additional factors modifying gene expression does not allow reproducible production of human neural stem cell-like progenitors that can be used as the source of neural tissue for the regenerative therapy.

Tissue Engineered Neural Constructs Composed of Neural Precursor Cells, Recombinant Spidroin and PRP for Neural Tissue Regeneration.

We have designed a novel two-component matrix (SPRPix) for the encapsulation of directly reprogrammed human neural precursor cells (drNPC). The matrix is comprised of 1) a solid anisotropic complex scaffold prepared by electrospinning a mixture of recombinant analogues of the spider dragline silk proteins - spidroin 1 (rS1/9) and spidroin 2 (rS2/12) - and polycaprolactone (PCL) (rSS-PCL), and 2) a "liquid matrix" based on platelet-rich plasma (PRP). The combination of PRP and spidroin promoted drNPC proliferation with the formation of neural tissue organoids and dramatically activated neurogenesis. Differentiation of drNPCs generated large numbers of ßIII-tubulin and MAP2 positive neurons as well as some GFAP-positive astrocytes, which likely had a neuronal supporting function. Interestingly the SPRPix microfibrils appeared to provide strong guidance cues as the differentiating neurons oriented their processes parallel to them. Implantation of the SPRPix matrix containing human drNPC into the brain and spinal cord of two healthy Rhesus macaque monkeys showed good biocompatibility: no astroglial and microglial reaction was present around the implanted construct. Importantly, the human drNPCs survived for the 3 month study period and differentiated into MAP2 positive neurons. Tissue engineered constructs based on SPRPix exhibits important attributes that warrant further examination in spinal cord injury treatment.

Development of a motor and somatosensory evoked potentials-guided spinal cord Injury model in non-human primates.

Background Nonhuman primates (NHP) may provide the most adequate (in terms of neuroanatomy and neurophysiology) model of spinal cord injury (SCI) for testing regenerative therapies, but bioethical considerations exclude their use in severe SCI. New Method A reproducible model of SCI at the lower thoracic level has been developed in Rhesus macaques. The model comprises surgical resection of 25% of the spinal cord in the projection of the dorsal funiculus and dorsolateral corticospinal pathways, controlled via registration of intraoperative evoked potentials (EPs). The animals were evaluated using the modified Hindlimb score, MRI, SSEP, and MEP over a time period of 8-12 weeks post-SCI, followed by histological examination. Results Complete disappearance of intraoperative EPs from distal hindlimb muscles without restoration within two weeks post-SCI was an indicator for irreversible disruption of the abovementioned pathways. As a result, controlled damage to the spinal cord was achieved in three NHPs, clinically manifested as irreversible lower monoplegia. No significant functional restoration was observed in these NHPs up to 12 weeks post-SCI. Demyelination of the damaged ascending tracts was detected. Disturbances in pelvic organ function were not observed in all animals. Comparison with existing methods The new method of EPs-guided SCI allows a more controlled and irreversible damage to the spinal cord compared with contusion and other transection approaches. Conclusions This method to induce complete SCI in NHP is well tolerated, reproducible and ethically acceptable: these are valuable attributes in a preclinical model that will hopefully help advance testing of new regenerative therapies in SCI.

Adult Neural Stem Cells: Basic Research and Production Strategies for Neurorestorative Therapy.

Over many decades, constructing genetically and phenotypically stable lines of neural stem cells (NSC) for clinical purposes with the aim of restoring irreversibly lost functions of nervous tissue has been one of the major goals for multiple research groups. The unique ability of stem cells to maintain their own pluripotent state even in the adult body has made them into the choice object of study. With the development of the technology for induced pluripotent stem cells (iPSCs) and direct transdifferentiation of somatic cells into the desired cell type, the initial research approaches based on the use of allogeneic NSCs from embryonic or fetal nervous tissue are gradually becoming a thing of the past. This review deals with basic molecular mechanisms for maintaining the pluripotent state of embryonic/induced stem and reprogrammed somatic cells, as well as with currently existing reprogramming strategies. The focus is on performing direct reprogramming while bypassing the stage of iPSCs which is known for genetic instability and an increased risk of tumorigenesis. A detailed description of various protocols for obtaining reprogrammed neural cells used in the therapy of the nervous system pathology is also provided.

Preventive efficacy of oxidized dextran and pathomorphological processes in mouse lungs in avian influenza A/H5N1.

Oxidized dextran (60 kDa) exerted a pronounced preventive effect in laboratory mice infected with avian influenza subtype H5N1 A/Goose/Krasnoozerskoye/627/05 virus, which manifested in a significant increase in mouse lifetime (by 24.4%) and a decrease in mortality rate (3.3-fold). This was probably related to significant alleviation of pathological changes in the lungs and severity of hemodynamic and inflammatory complications and early fibrosis [corrected].