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1.
Functional magnetic resonance imaging (fMRI) based on blood oxygen level-dependent (BOLD) contrast has become an invaluable tool in the assessment of in vivo neuronal activation. Quantification of the BOLD response is determined by the hemodynamic and metabolic changes that occur in response to brain stimulation. However, these changes may vary by changes in insulin, a hormone known to be vasoactive in some tissues. To determine if insulin has an effect on fMRI, we measured the BOLD response to a visual stimulus in five normal volunteers in which insulin was first suppressed and then brought to a high physiological concentration. In addition, we also examined the effect of insulin on activation of the visual cortex as measured by the visual-evoked potential (VEP). We found that the BOLD response measured in the presence of insulin (serum insulin=236+/-29 pmol/L) was significantly lower (P<0.001) than that measured in its absence (serum insulin=8+/-2 pmol/L). Insulin was without effect on P100 amplitude or latency acquired in the presence or absence of insulin in 28 subjects using the same stimulus as that used for the fMRI experiments. Our observations suggest that insulin may have effects on cerebral blood flow and/or metabolism that affect the BOLD signal that are independent of its effects on neuronal activation identified by event related potentials (ERP). These findings highlight the complexity that must be considered when interpreting differences in fMRI responses between groups of subjects that differ in insulin concentration and/or insulin sensitivity.  相似文献   
2.
Yun SI  Kim SY  Choi WY  Nam JH  Ju YR  Park KY  Cho HW  Lee YM 《Virus research》2003,96(1-2):129-140
We have determined the complete nucleotide and deduced amino acid sequences of the Japanese encephalitis virus (JEV) strain K87P39, isolated from a pool of circulating Culex tritaeniorhynchus mosquitoes in Korea. In comparison with 27 fully sequenced JEV genomes currently available, we found that the 10968-nucleotide RNA genome of K87P39 has a nine-nucleotide deletion in the 3' nontranslated variable region and that its single open reading frame has a total of eight amino acid substitutions. The K87P39 isolate is highly similar to other JEV isolates, and homology ranges from 97.9 to 89.0% at the nucleotide level, and 99.1 to 96.7% at the deduced amino acid level. Phylogenetic analyses using the full-length sequence of the 27 available JEV genomes showed that the K87P39 strain is most closely related to six Chinese SA14 derivatives and that it is distantly related to the Australian FU, Korean K94P05 and Japanese Ishikawa strains. In addition, we also found that phylogenetic relationships based on the full-length genome are highly similar to those based on the E gene, indicating that phylogenetic analysis of the E gene will be useful for studying the genetic relationships among JEV isolates. We therefore performed a more extensive E gene-based phylogenetic analysis on a selection of 70 JEV isolates available from GenBank, which represent a temporally and geographically wide variety of JEV strains.  相似文献   
3.
Somatic cell nuclear transfer (scNT) is a useful way to create cloned animals. However, scNT clones exhibit high levels of phenotypic instability. This instability may be due to epigenetic reprogramming and/or genomic damage in the donor cells. To test this, we produced transgenic pig fibroblasts harboring the truncated human thrombopoietin (hTPO) gene and used them as donor cells in scNT to produce first-generation (G1) cloned piglets. In this study, 2,818 scNT embryos were transferred to 11 recipients and five G1 piglets were obtained. Among them, a clone had a dimorphic facial appearance with severe hypertelorism and a broad prominent nasal bridge. The other clones looked normal. Second-generation (G2) scNT piglets were then produced using ear cells from a G1 piglet that had an abnormal nose phenotype. We reasoned that, if the phenotypic abnormality of the G1 clone was not present in the G2 and third-generation (G3) clones, or was absent in the G2 clones but reappeared in the G3 clones, the phenotypic instability of the G1 clone could be attributed to faulty epigenetic reprogramming rather than to inherent/accidental genomic damage to the donor cells. Blastocyst rates, cell numbers in blastocyst, pregnancy rates, term placenta weight and ponderal index, and birth weight between G1 and G2 clones did not differ, but were significantly (P < 0.05) lower than control age- and sex-matched piglets. Next, we analyzed global methylation changes during development of the preimplantation embryos reconstructed by donor cells used for the production of G1 and G2 clones and could not find any significant differences in the methylation patterns between G1 and G2 clones. Indeed, we failed to detect the phenotypic abnormality in the G2 and G3 clones. Thus, the phenotypic abnormality of the G1 clone is likely to be due to epigenetic dysregulation. Additional observations then suggested that expression of the hTPO gene in the transgenic clones did not appear to be the cause of the phenotypic abnormality in the G1 clones and that the abnormality was acquired by only a few of the G1 clone's cells during its gestational development.  相似文献   
4.
Journal of Neurology - To define the prevalence and characteristics of single ocular motor nerve palsy (OMNP) associated with positive serum anti-GQ1b antibody. We performed a prospective...  相似文献   
5.
This study evaluated the outcomes and prognostic factors for breast cancer according to initial lymph node (LN) status. Among patients with LN-negative breast cancer, we also focused on the prognostic value of estrogen receptor (ER) status.Medical records were retrospectively reviewed for 715 patients who underwent curative surgery for breast cancer between January 2005 and December 2015 at a single Korean institution. We evaluated factors that were associated with metastasis-free survival (MFS) according to LN status.Among the 715 patients (age: 28–87 years), 458 patients (64.1%) did not have axillary LN metastasis. Relative to patients without LN metastasis, patients with LN metastasis had larger tumor sizes and higher histological grades. Among patients with no LN metastasis, ER positivity was associated with non-significantly poorer MFS than ER negativity (mean survival: 138.90 months vs. 146.99 months, p = .17), and patients with LN-negative ER-positive disease had MFS rates of 91.7% at 5 years and 74.5% at 10 years. Among patients with LN-negative ER-positive disease, a poor prognosis was significantly associated with larger tumor size (≥2 cm, P = .03) and older age (≥50 years, P = .03).These results indicate that the risk of metastasis increases over time for patients with LN-negative ER-positive breast cancer, and especially for older patients or patients with larger tumors.  相似文献   
6.
The aim of this study was to assess the effect of idiopathic Optic perineuritis on the retinal nerve fiber layer, and determine the ability of optical coherence tomography to evaluate retinal nerve fiber loss after idiopathic Optic perineuritis. Four patients were assessed in this study. In all cases, average retinal nerve fiber layer was significantly thinner in the affected eye in comparison with the normal reference value and with the value for the contralateral normal eye at 12 months after the onset of optic perineuritis. Our study revealed that retinal nerve fiber layer loss occurs in idiopathic optic nerve sheath inflammation.  相似文献   
7.
8.
Ecotoxicology - We investigated the effects of nanoscale zero-valent iron (nZVI) that has been widely used for groundwater remediation on a terrestrial crop, Medicago sativa (Alfalfa), and...  相似文献   
9.
Chemically synthesized small interfering RNA (siRNA) has been used as an anti-coxsackievirus B3 (CVB3) agent. Herein, we investigated whether vector-derived short hairpin RNAs (shRNA) targeting CVB3 can exert antiviral activities, prior to their further application to viral vector system for efficient in vivo administration. Employing transient transfection assays to in vivo mouse models as well as to in vitro Cos-7 cell cultures, we directly demonstrated the potential antiviral activity of shRNAs following challenges with infectious CVB3. Of the six shRNAs that we designed, three prevented cell death from CVB3 infection by suppressing viral replication and viral production in Cos-7 cells. These were shRNA 2, which targeted the capsid protein VP1, and shRNAs 4 and 5, which targeted two different regions of the RNA-dependent RNA polymerase 3D. Furthermore, shRNAs 2 and 5 also exerted strong antiviral effects in viral replication in vivo, accompanied by attenuated pancreatic tissue damage. Through this direct evaluation system we addressed the development and application of vector-derived shRNAs as an anti-CVB3 agent, revealing new target sequences.  相似文献   
10.
OBJECTIVE: The coxsackie and adenovirus receptor (CAR) and the decay-accelerating factor (DAF) are receptors for coxsackievirus B3 (CVB3), which is known as the major cause of human viral myocarditis. We investigated the potential for therapeutic use of soluble virus receptor fusion proteins. METHODS: We designed and generated a novel virus receptor trap (hCAR-hDAF:Fc) consisting of both CVB3 receptors and the Fc portion of human IgG1 and evaluated its antiviral effects in experimental CVB3 myocarditis. RESULTS: Among four soluble virus receptor fusion proteins (hCAR:Fc, hDAF:Fc, hCAR-hDAF:Fc and hDAF-hCAR:Fc), hCAR:Fc and hCAR-hDAF:Fc in the supernatant of transfected cells neutralized echovirus, adenovirus, and various serotypes of CVB in a dose-dependent manner. Both soluble viral receptor proteins bound to the VP0 and VP1 capsid proteins of CVB3. The in vivo efficacy of viral receptor proteins was evaluated by intramuscular injection of plasmid (hCAR:Fc or hCAR-hDAF:Fc) followed by electroporation in a murine model of CVB3 myocarditis. Serum levels of the virus receptor proteins increased relative to baseline values from day 3 and peaked on day 14 at 12.9-fold for hCAR:Fc and 7.1-fold for hCAR-hDAF:Fc. The 3-week survival rate was significantly higher in hCAR-hDAF:Fc-treated mice (61%) than in hCAR:Fc-treated mice (29%) and in controls (15%; p<0.05). Myocardial inflammation, fibrosis, and myocardial virus titers were all significantly reduced in the hCAR:Fc and hCAR-hDAF:Fc groups compared to the controls. CONCLUSION: Our soluble virus receptor trap, hCAR-hDAF:Fc, attenuated viral infection, myocardial inflammation, and fibrosis, resulting in higher survival rates in mice with coxsackieviral myocarditis. Furthermore, it consists exclusively of human components, and we demonstrated that this soluble virus receptor trap may be used as a potential candidate for a novel therapeutic agent for the treatment of acute viral myocarditis during the viremic phase.  相似文献   
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