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91.
ObjectiveNeuropsychiatric lupus (NPSLE), a manifestation of the autoimmune disease systemic lupus erythematosus (SLE), is characterized by psychiatric symptoms including anxiety and depression and upregulated autoantibodies. The B6.Nba2 spontaneous mouse model develops SLE, but has not previously been tested for NPSLE.MethodsWe investigated the NPSLE phenotype in male and female B6.Nba2 mice (n = 12 each) and age- and sex-matched B6 controls (n = 10 each) via behavioral assessments for anxiety, depression, and memory deficits. Serum anti-dsDNA, anti-nRNP, anti-DWEYS peptide reactive IgG autoantibody levels and soluble TWEAK levels were determined by ELISA. Hippocampal regions were stained for activated microglia and neurons.ResultsBoth male and female B6.Nba2 mice showed elevated anti-dsDNA IgG, anti-nRNP IgG and anti-DWEYS reactive antibodies, elevated serum soluble TWEAK levels, and a strong anxiety and depression phenotype (p < 0.05–0.0001). Male B6.Nba2 mice developed this phenotype at a slightly older age than females. Female B6.Nba2 mice displayed reduced numbers of neurons in the hippocampal region compared to female B6 controls (p < 0.05).ConclusionThe B6.Nba2 mouse model recapitulates many known NPSLE phenotypes, making it a promising model to investigate the development of NPSLE in the context of SLE. 相似文献
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Zahra Hassannejad Shayan Abdollah Zadegan Alexander R. Vaccaro Vafa Rahimi-Movaghar Omid Sabzevari 《Injury》2019,50(2):278-285
Background
The complex pathophysiological events occurring after traumatic spinal cord injuries (TSCI) make this devastating trauma still incurable. Peptide amphiphile (PA) hydrogels are nanobiomaterials displaying desirable properties for application in regenerative medicine because they are absorbable, injectable, allowing biofunctionalization, controlling release of trophic factors and mimic extracellular matrix (ECM). In this study, we explored the potentiality of the IKVAV-functionalized PA hydrogel to provide a permissive environment for cell migration and growth as well as sustained release of BDNF at the lesion after severe compression injury model.Methods
The IKVAV-functionalized PA was synthesized by automated solid-phase approach and its secondary structure was evaluated by Circular dichroism (CD) spectroscopy. The potential of IKVAV-functionalized PA to self-assemble into nanofibers and hydrogel formation were assessed using transmission electron microscopy (TEM). Release profiles of BDNF from hydrogel and the bioactivity of the released BDNF from hydrogel were determined using ELISA and DRG bioassay, respectively. Severe spinal cord injury was induced using clip compression at T7-T8 vertebral segment. Twenty four hours post-injury the animals were treated by either IKVAV PA hydrogel, BDNF-loaded IKVAV PA hydrogel, BDNF solution or saline. Two and six weeks later, animals were sacrificed and the lesion site was evaluated based on GFAP, CD68 and ß III tubulin immunoreactivity. Also, locomotor recovery was assessed during 6 weeks using Basso, Beattie, Bresnahan (BBB) scoring test.Results
The IKVAV PA arranged into nanofibrous structure and provided a sustained release of BDNF over 21 days while preserved the bioactivity of BDNF. Also, BDNF loading influenced the hydrogel nanostructure resulting in aligned orientation of nanofibers. Injection of BDNF-loaded IKVAV PA hydrogel resulted in a considerable axon preservation and astrogliosis reduction at 6 weeks post-injury without showing any inflammatory reaction. However, the BBB score was not statistically different between different treatment groups.Conclusion
Although the locomotor functional recovery was not observed in this study, the axon preservation and minimal inflammation in animals treated with BDNF-incorporated hydrogel indicate the potentiality of the designed intervention for further evaluations in the path of developing efficient therapies for severe spinal cord injury. 相似文献93.
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ABSTRACTGrowing trees on farmland continues to be a promising land-use option for smallholders in Indonesia as they look to diversify their enterprises beyond the main agricultural sector. While most smallholders integrate trees into their farming systems, selling timber and other tree products has usually been infrequent and opportunistic. Because of this infrequent trade, most smallholders rarely adopt silvicultural practices that would increase the commercial value of their trees. A research project trialled an alternative approach to forestry extension in Indonesia, known as the Master TreeGrower (MTG) training course. The MTG training courses used a farmer-centred approach to teach smallholders about forest science and took participants to market hubs so they could better understand how different forest products were valued by traders. The MTG training approach was trialled in 2014 in five districts in Indonesia and involved 118 smallholders and 27 non-farmers as course participants. This article reports on a recent evaluation of the MTG training courses held about three years earlier to explore the enduring impacts of the training approach and whether it can be scaled-out to other areas of Indonesia. The evaluation data were collected via focus group discussions (FGDs), in-depth interviews, household surveys and observations at three project sites: Pati (Central Java), Gunungkidul (Yogyakarta) and Bulukumba (South Sulawesi). A questionnaire was distributed among the participants of the FGDs to assess the extent different knowledge and skills of tree management that had been adopted by them following the MTG courses. The evaluation of the MTG approach revealed that the courses were effective in increasing smallholders’ knowledge of commercial forestry and their silvicultural skills. Many participants were more active with silviculture and planned to invest further in commercial forestry following the MTG training. In effect, the MTG training appeared to change the hearts and minds of the farmers about how commercial forestry could enhance their livelihoods. 相似文献
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