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851.
We have screened new drugs with a view to developing effective drugs against glutamate-induced excitotoxicity. In the present work, we show effects of a new drug, 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride against glutamate-induced excitotoxicity in primary rat glial cultures. Pretreatment of glial cells with 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride for 2 h significantly protected glial cells against glutamate-induced excitotoxicity in a time- and dose-dependent manner with an optimum concentration of 100 μM. The drug significantly reduced production of proinflammatory cytokines, tumor necrosis factor-α, and interlukin-1β in glutamate-induced excitotoxicity. The drug also prevented glutamate-induced intracellular Ca2+ influx and reduced the subsequent overproduction of nitric oxide and reactive oxygen species. Furthermore, the drug preserved the mitochondrial potential and inhibited the overproduction of cytochrome c. In addition, the drug effectively attenuated the protein level changes of β-catenin and glycogen synthase kinase-3β. These results suggest that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride effectively protected primary cultures of rat glial cells against glutamate-induced excitotoxicity.  相似文献   
852.
In this study, we observed the effects of lipopolysaccharide (LPS) on neurodegeneration and immune response in the hippocampus. LPS is a gram-negative bacterial cell surface proteoglycan and known as a bacterial endotoxin. For this, we investigated the optimal concentration of LPS influencing the ICR mouse hippocampus to measure the LPS receptor, e.g., toll-like receptor 4 (TLR4), expression in mouse hippocampal homogenates. TLR4 expression was significantly and prominently increased in the hippocampal homogenates of the LPS (1 mg/kg)-treated group. Next, we examined pro-inflammatory response in the hippocampus using cyclooxygenase-2 (COX-2, a marker for inflammatory response) immunohistochemistry after LPS treatment. COX-2 immunoreactivity was significantly increased in the endothelium of blood vessels in the hippocampus 6 h after LPS treatment, judging from double immunofluorescence study with platelet-derived endothelial cell adhesion molecule-1 (PECAM-1, a marker for endothelial cells): it decreased 12 h and disappeared 24 h after LPS treatment. In addition, the ionized calcium-binding adapter molecule 1 (Iba-1)-immunoreactive (+) microglia were morphologically activated in the mouse hippocampus after LPS treatment. At 24 h after LPS treatment, Iba-1+ microglia of activated forms were abundant in the hippocampus. However, NeuN (a neuron-specific soluble nuclear antigen)+ neurons were not significantly changed in the hippocampus after LPS treatment. Fluoro-jade B (a marker for neuronal degeneration)+ cells were not detected in the hippocampus at any time after LPS treatment. In addition, there were no significant differences in permeability of blood–brain barriers at any time points after LPS treatment. In brief, our results indicate that intraperitoneal administration of 1 mg/kg LPS effectively induces LPS receptor (TLR4) expression in the hippocampus, and the treatment increases corticosterone levels, inflammation in the blood vessels, and microglial activation in the hippocampus without any neuronal damage.  相似文献   
853.
Small nucleolar RNAs (snoRNAs) and small Cajal body-specific RNAs (scaRNAs) are non-coding RNAs whose main function in eukaryotes is to guide the modification of nucleotides in ribosomal and spliceosomal small nuclear RNAs, respectively. Full-length sequences of Arabidopsis snoRNAs and scaRNAs have been obtained from cDNA libraries of capped and uncapped small RNAs using RNA from isolated nucleoli from Arabidopsis cell cultures. We have identified 31 novel snoRNA genes (9 box C/D and 22 box H/ACA) and 15 new variants of previously described snoRNAs. Three related capped snoRNAs with a distinct gene organization and structure were identified as orthologues of animal U13snoRNAs. In addition, eight of the novel genes had no complementarity to rRNAs or snRNAs and are therefore putative orphan snoRNAs potentially reflecting wider functions for these RNAs. The nucleolar localization of a number of the snoRNAs and the localization to nuclear bodies of two putative scaRNAs was confirmed by in situ hybridization. The majority of the novel snoRNA genes were found in new gene clusters or as part of previously described clusters. These results expand the repertoire of Arabidopsis snoRNAs to 188 snoRNA genes with 294 gene variants.  相似文献   
854.
The inulinase gene (INU1) from Kluyveromyces marxianus NCYC2887 strain was overexpressed by using GAL10 promotor in a △gal80 strain of Saccharomyces cerevisiae. The inulinase gene lacking the original signal sequence was fused in-frame to mating factor alpha signal sequence for secretory expression. Use of the △gal80 strain allowed the galactose-free induction of inulinase expression using a glucose-only medium. Shake flask cultivation in YPD medium produced 34.6 U/ml of the recombinant inulinase, which was approximately 13-fold higher than that produced by K. marxianus NCYC2887. It was found that the use of the △gal80 strain improved the expression of inulinase in the recombinant S. cerevisiae in both the aerobic and the anaerobic condition by about 2.9- and 1.7-fold, respectively. 5 L fed-batch fermentation using YPD medium was performed under aerobic condition with glucose feeding, which resulted in the inulinase production of 31.7 U/ml at OD600 of 67. Ethanol fermentation of dried powder of Jerusalem artichoke, an inulin-rich biomass, was also performed using the recombinant S. cerevisiae expressing INU1 and K. marxianus NCYC2887. Fermentation in a 5L scale fermentor was carried out at an aeration rate of 0.2 vvm, an agitation rate of 300 rpm, and the pH was controlled at 5.0. The temperature was maintained at 30degrees C and 37degrees C, respectively, for the recombinant S. cerevisiae and K. marxianus. The maximum productivities of ethanol were 59.0 and 53.5 g/L, respectively.  相似文献   
855.

Background

Enzyme replacement therapy (ERT) with α-galactosidase A (α-Gal A) is currently the most effective therapeutic strategy for patients with Fabry disease, a lysosomal storage disease. However, ERT has limitations of a short half-life, requirement for frequent administration, and limited efficacy for patients with renal failure. Therefore, we investigated the efficacy of recombinant adeno-associated virus (rAAV) vector-mediated gene therapy for a Fabry disease mouse model and compared it with that of ERT.

Methods

A pseudotyped rAAV2/8 vector encoding α-Gal A cDNA (rAAV2/8-hAGA) was prepared and injected into 18-week-old male Fabry mice through the tail vein. The α-Gal A expression level and globotriaosylceramide (Gb3) levels in the Fabry mice were examined and compared with Fabry mice with ERT. Immunohistochemical and ultrastructural studies were conducted.

Results

Treatment of Fabry mice with rAAV2/8-hAGA resulted in the clearance of accumulated Gb3 in tissues such as liver, spleen, kidney, heart, and brain with concomitant elevation of α-Gal A enzyme activity. Enzyme activity was elevated for up to 60 weeks. In addition, expression of the α-Gal A protein was identified in the presence of rAAV2/8-hAGA at 6, 12, and 24 weeks after treatment. α-Gal A activity was significantly higher in the mice treated with rAAV2/8-hAGA than in Fabry mice that received ERT. Along with higher α-Gal A activity in the kidney of the Fabry mice treated with gene therapy, immunohistochemical studies showed more α-Gal A expression in the proximal tubules and glomerulus, and less Gb3 deposition in Fabry mice treated with this gene therapy than in mice given ERT. The α-gal A gene transfer significantly reduced the accumulation of Gb3 in the tubules and podocytes of the kidney. Electron microscopic analysis of the kidneys of Fabry mice also showed that gene therapy was more effective than ERT.

Conclusions

The rAAV2/8-hAGA mediated α-Gal A gene therapy provided improved efficiency over ERT in the Fabry disease mouse model. Furthermore, rAAV2/8-hAGA-mediated expression showed a greater effect in the kidney than ERT.
  相似文献   
856.
Phosphorylated extracellular signal-regulated kinase (pERK) mediates neuronal synaptic plasticity, long-term potentiation, and learning and memory in the hippocampus. In this study, we examined pERK1/2 immunoreactivity and its protein level in the gerbil hippocampus at various ages. In the postnatal month 1 (PM 1) group, very weak pERK1/2 immunoreactivity was detected in the hippocampus. In the CA1 region, pERK1/2 immunoreactivity was considerably increased in the stratum pyramidale in the PM 6 group. Thereafter, pERK1/2 immunoreactivity was decreased. In the CA2/3 region, pERK1/2 immunoreactivity increased in an age-dependent manner until PM 12. Thereafter, numbers of pERK1/2-immunoreactive neurons were decreased. However, in the mossy fiber zone, pERK1/2 immunostaining became stronger with age. In the dentate gyrus, a few pERK1/2-immunoreactive cells were observed until PM 12. In the PM 18 and 24 groups, numbers of pERK1/2-immunoreactive cells were increased, especially in the polymorphic layer. In Western blot analysis, pERK1/2 level in the gerbil hippocampus was increased with age. These results indicate that total pERK1/2 levels are increased in the hippocampus with age. However pERK1/2 immunoreactivity in subregions of the gerbil hippocampus was changed with different pattern during normal aging.  相似文献   
857.
Yi DK  Sun IC  Ryu JH  Koo H  Park CW  Youn IC  Choi K  Kwon IC  Kim K  Ahn CH 《Bioconjugate chemistry》2010,21(12):2173-2177
Herein, we developed matrix metalloprotease (MMP) sensitive gold nanorods (MMP-AuNR) for cancer imaging and therapy. It was feasible to absorb NIR laser and convert into heat as well as visualize MMP activity. We showed the possibility of gold nanorods as a hyperthermal therapeutic agent and MMP sensitive imaging agent both in vitro and in vivo condition. The results suggested potential application of MMP-AuNR for simultaneous cancer diagnosis and therapy.  相似文献   
858.
Previously, three extracellular proteases, Vpr, PepT, and subtilisin were identified from Bacillus subtilis KCTC 3014. To confirm the activity of Vpr, two recombinant Vpr proteins, full Vpr with TTG (pGST-fTTG-Vpr) and full Vpr with ATG (pGST-fATG-Vpr) as an initiation codon were expressed using a pGEX-2T vector encoding glutathione S-transferase (GST) in Escherichia coli. Vpr was produced in two forms, occurring as four spots on a 2-DE gel, 68 and 75 kDa proteins with similar pI values (4.0 ∼ 4.5). Activity was detected in a fibrin zymography at the expected molecular size of 68 kDa (mature form) processed from full Vpr. However, the recombinant 75 kDa of GST-fVpr did not exhibit activity. Replacement of the TTG codon with ATG led to 1.9-fold increased enzyme activity in 68 kDa. Interestingly, the expression of GSTVpr resulted in the proteolytic degradation of the protein and no GST fusion Vpr protein was detected.  相似文献   
859.
In situ hybridization methods enable the mapping of mRNA expression within intact biological samples. With current approaches, it is challenging to simultaneously map multiple target mRNAs within whole-mount vertebrate embryos, representing a significant limitation in attempting to study interacting regulatory elements in systems most relevant to human development and disease. Here, we report a multiplexed fluorescent in situ hybridization method based on orthogonal amplification with hybridization chain reactions (HCR). With this approach, RNA probes complementary to mRNA targets trigger chain reactions in which fluorophore-labeled RNA hairpins self-assemble into tethered fluorescent amplification polymers. The programmability and sequence specificity of these amplification cascades enable multiple HCR amplifiers to operate orthogonally at the same time in the same sample. Robust performance is achieved when imaging five target mRNAs simultaneously in fixed whole-mount and sectioned zebrafish embryos. HCR amplifiers exhibit deep sample penetration, high signal-to-background ratios and sharp signal localization.  相似文献   
860.
Life history theory views reproduction as an outcome of resource allocation. The allocation of resources such as parental investments of time, energy and material resources involves trade-offs between number of offspring and timing of reproduction. Within the framework of mammalian parental investment, the outstanding feature of human reproduction is the high level of paternal care. Although empirical evidence suggests that human paternal investment may have evolved as a reproductive strategy to reduce infant and child mortality rates, the effects of actual paternal investment, including allocating time to child care, on female reproductive decisions have received relatively little attention. We examined the trade-off from two perspectives using a representative sample of married South Korean women aged 20–44 in 2005 (n=977). First, paternal investment in domestic labor, including child care and housework, was expected to be associated with women's preference regarding future reproduction. Second, relative paternal investment was expected to increase women's preference for future reproduction, especially among employed women. We found that increased paternal investment in child care and housework remarkably enhanced women's intention to have a second child, especially among employed women. In addition, although family members provide a low percentage of child care in South Korea, such help is likely to be a useful resource for second childbirth among employed women. Somewhat expectedly, older age and longer time since first birth had negative effects on women's second-child intention. There is growing evidence that, in the lowest fertility societies, paternal investment may be an essential resource for promoting future reproductive behavior of women, especially employed women.  相似文献   
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