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1.
Local community participation and ex situ conservation has the potential to assist the recovery of the endangered Egyptian tortoise, Testudo kleinmanni. We initiated an in situ community‐based conservation and research program from a captive population of T. kleinmanni. We used a captive population of the Egyptian tortoise to train a member of the local community as a research technician and used his indigenous tracking skills and knowledge of the area to collect activity and dietary data on 28 captive tortoises. We overcame problems with illiteracy by creating a data sheet based on symbols and numbers. This data sheet allowed us to use the indigenous knowledge of various people from the community, and employ them in the future. Our local community approach to data collection, in conjunction with a craft program, made the conservation of the Egyptian tortoise more rewarding to the local community by providing a more sustainable form of income than collecting animals for the pet trade. Our multidimensional approach (local community participation as research technicians, craft program, and trust building) for gaining local support eventually led to the rediscovery of wild Egyptian tortoises in North Sinai, which was significant, as this species was presumed extinct in Egypt. We have now shifted our focus to in situ conservation, using the research and local capacity building template developed from this captive population study. Our template can be used by zoos and conservation organizations with small budgets and collections of native species in natural habitats to create similar captive research programs that can be applied to in situ conservation. Zoo Biol 26:397–406, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
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The title compound, 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione (C24H22N2O2S), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a?=?19.7799(13) Å, b?=?6.7473(4) Å, c?=?15.7259(9) Å and β?=?103.416(5)°. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31G(d), 6–31 + G(d,p) and LANL2DZ basis sets, and compared with the experimental data. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 5°. Besides, molecular electrostatic potential, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were investigated by theoretical calculations.  相似文献   
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Objective

To determine the effect of laser needle-knife on PI-3K, AKT and VEGF mRNA expression of vertebral arteries in a rabbit model of cervical spondylotic arteriopathy (CSA) and the mechanism of action involved.

Methods

Forty healthy general-grade rabbits were divided into a normal control group, model group, acupuncture group, and laser needle-knife group (n?=?10 rabbits per group), and the CSA rabbit model was established in all but groups but the normal control group. CSA model rabbits in the acupuncture group were treated by acupuncture at the Fengchi (GB 20) and Cervical Jiaji (EX-B 2) points, whereas rabbits in the laser needle-knife group were treated with laser needle-knife targeting the Jiaji points near the C5 spinous process. Rabbits in the normal control and model groups were fixed using similar methods. Behavioral characteristics of all rabbits were evaluated before and after treatment. Peak systolic velocity (PSV) of the right carotid and vertebral arteries in each group were examined using beside B ultrasound, and PI-3K, AKT, VEGF mRNA expression in vertebral arteries were determined by real-time PCR.

Results

The behavioral signs of rabbits were improved after treatment in both the acupuncture and laser needle-knife groups. In comparison with control group, PSV of right carotid arteries in acupuncture group and laser needle-knife group were enhanced significantly (P?<?0.05 and P?<?0.01), PSV of right vertebral arteries in acupuncture group and laser needle-knife group were enhanced significantly too (P?<?0.01 and P?<?0.05). PI-3K mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group (P?<?0.01, P?<?0.05). AKT mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group (P?<?0.01). VEGF mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group too (P?<?0.01, P?<?0.05). No significant differences were found in PI-3K, AKT and VEGF mRNA expression levels among acupuncture and laser needle-knife groups (P?>?0.05).

Conclusion

Laser needle-knife could effectively intervene the mRNA expression of PI-3K, AKT and VEGF, this may be one of the mechanisms of the effect of laser needle-knife in treating CSA in rabbits.  相似文献   
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Human cardiac progenitor cells (hCPC) improve heart function after autologous transfer in heart failure patients. Regenerative potential of hCPCs is severely limited with age, requiring genetic modification to enhance therapeutic potential. A legacy of work from our laboratory with Pim1 kinase reveals effects on proliferation, survival, metabolism, and rejuvenation of hCPCs in vitro and in vivo. We demonstrate that subcellular targeting of Pim1 bolsters the distinct cardioprotective effects of this kinase in hCPCs to increase proliferation and survival, and antagonize cellular senescence. Adult hCPCs isolated from patients undergoing left ventricular assist device implantation were engineered to overexpress Pim1 throughout the cell (PimWT) or targeted to either mitochondrial (Mito-Pim1) or nuclear (Nuc-Pim1) compartments. Nuc-Pim1 enhances stem cell youthfulness associated with decreased senescence-associated β-galactosidase activity, preserved telomere length, reduced expression of p16 and p53, and up-regulation of nucleostemin relative to PimWT hCPCs. Alternately, Mito-Pim1 enhances survival by increasing expression of Bcl-2 and Bcl-XL and decreasing cell death after H2O2 treatment, thereby preserving mitochondrial integrity superior to PimWT. Mito-Pim1 increases the proliferation rate by up-regulation of cell cycle modulators Cyclin D, CDK4, and phospho-Rb. Optimal stem cell traits such as proliferation, survival, and increased youthful properties of aged hCPCs are enhanced after targeted Pim1 localization to mitochondrial or nuclear compartments. Targeted Pim1 overexpression in hCPCs allows for selection of the desired phenotypic properties to overcome patient variability and improve specific stem cell characteristics.  相似文献   
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The Abeta (amyloid‐beta) peptide is derived from the sequential cleavage of AbetaPP (amyloid‐beta precursor protein) by two enzymes, the β‐ and γ‐secretases. The major β‐secretase, identified as the novel transmembrane aspartic protease BACE1 (beta site APP‐cleaving enzyme 1), mediates the primary amyloidogenic cleavage of AbetaPP and initiates the production of Abeta. It has been implicated in the proteolytic processing of another substrate, namely ST6Gal1 (β galactoside α2,6‐sialyltransferase 1), which is the major α2,6‐sialyltransferase responsible for the broad synthesis of glycoproteins and glycolipids. The present study investigated the effect of overexpression of AbetaPP on expression and secretion of ST6Gal1 in skeletal muscle cells by inducing overexpression of wild‐type full‐length 751‐AbetaPP in the mouse myogenic cell line C2C12. Expression and secretion of the ST6Gal1 enzyme were analysed by Western blot and/or immunofluorescence staining. The results of our study demonstrated that AbetaPP overexpression in C2C12 cells increased the expression and the secretion of ST6Gal1 enzyme in vitro.  相似文献   
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Genetic variations of microRNA encoding genes influence various sorts of diseases by modifying the expression or activity of microRNAs. MicroRNA 146a is an epigenetic regulator of immune response through controlling the type I interferon (IFN) and nuclear factor kappa B (NF-κB) pathways. Genetic variations of microRNA 146a impact the susceptibility to systemic lupus erythematosus (SLE) and its clinical presentations. This study aimed to investigate the polymorphisms of microRNA-146a gene (rs2431697 and rs57095329) in patients with SLE and its association with disease activity. Sixty-five patients with SLE and 40 apparently healthy controls were enrolled in this study. Patients were subjected to history taking, clinical examination, and disease activity evaluation by SLEDAI score. The microRNA-146a variants were determined by allele discrimination real-time PCR method in all participants. We found a statistically significant association between rs2431697 T allele and SLE (P-value?<?0.05), but there was no significant association between rs57095329 and SLE. The T/T genotype of microRNA-146a rs2431697 was associated with lupus nephritis, higher disease activity, and autoantibodies production. The microRNA-146a rs2431697 T allele could be a potential risk factor that contributes to SLE susceptibility, development of lupus nephritis, and disease activity.

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