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911.
Carnosic acid, a diterpene in rosemary, is considered to be beneficial in the prevention of chronic neurodegenerative diseases. Recently, it has been found that drugs with antiangiogenic activity lower the risk of neurodegenerative diseases. Thus it is of interest whether carnosic acid has antiangiogenic activity. In this study, carnosic acid suppressed microvessel outgrowth on ex vivo angiogenesis assay using a rat aortic ring at higher than 10 μM. The antiangiogenic effect of carnosic acid was found in angiogenesis models using human umbilical vein endothelial cells with regard to tube formation on reconstituted basement membrane, chemotaxis and proliferation. Although the carnosol in rosemary also suppressed angiogenesis, its effect was not more potent than that of carnosic acid in the ex vivo model. These results suggest that carnosic acid and rosemary extract can be useful in the prevention of disorders due to angiogenesis, and that their antiangiogenic effect can contribute to a neuroprotective effect.  相似文献   
912.
Lassa virus (LASV) is the causative agent of Lassa fever (LF), which presents as a lethal hemorrhagic disease in severe cases. LASV-induced hearing loss in survivors is a huge socioeconomic burden, however, the mechanism(s) leading to hearing loss is unknown. In this study, we evaluate in a mouse LF model the auditory function using auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) to determine the mechanisms underlying LASV-induced hearing loss. In the process, we pioneered measures of ABR and DPOAE tests in rodents in biosafety level 4 (BSL-4) facilities. Our T cell depletion studies demonstrated that CD4 T-cells play an important role in LASV-induced hearing loss, while CD8 T-cells are critical for the pathogenicity in the acute phase of LASV infection. Results presented in this study may help to develop future countermeasures against acute disease and LASV-induced hearing loss.  相似文献   
913.
Our laboratory has reported that central command blunts the sensitivity of the aortic baroreceptor-heart rate (HR) reflex at the onset of voluntary static exercise in conscious cats and spontaneous contraction in decerebrate cats. The purpose of this study was to examine whether central command attenuates the sensitivity of the carotid sinus baroreceptor-HR reflex at the onset of spontaneous, fictive motor activity in paralyzed, decerebrate cats. We confirmed that aortic nerve (AN)-stimulation-induced bradycardia was markedly blunted to 26 ± 4.4% of the control (21 ± 1.3 beats/min) at the onset of spontaneous motor activity. Although the baroreflex bradycardia by electrical stimulation of the carotid sinus nerve (CSN) was suppressed (P < 0.05) to 86 ± 5.6% of the control (38 ± 1.2 beats/min), the inhibitory effect of spontaneous motor activity was much weaker (P < 0.05) with CSN stimulation than with AN stimulation. The baroreflex bradycardia elicited by brief occlusion of the abdominal aorta was blunted to 36% of the control (36 ± 1.6 beats/min) during spontaneous motor activity, suggesting that central command is able to inhibit the cardiomotor sensitivity of arterial baroreflexes as the net effect. Mechanical stretch of the triceps surae muscle never affected the baroreflex bradycardia elicited by AN or CSN stimulation and by aortic occlusion, suggesting that muscle mechanoreflex did not modify the cardiomotor sensitivity of aortic and carotid sinus baroreflex. Since the inhibitory effect of central command on the carotid baroreflex pathway, associated with spontaneous motor activity, was much weaker compared with the aortic baroreflex pathway, it is concluded that central command does not force a generalized modulation on the whole pathways of arterial baroreflexes but provides selective inhibition for the cardiomotor component of the aortic baroreflex.  相似文献   
914.

Purpose

We evaluated the prevalence and characteristics of the defects of the lamina cribrosa (LC) in high myopia and glaucoma, and compared them with control eyes using swept-source optical coherence tomography (SS-OCT).

Methods

One hundred fifty-nine eyes of 108 participants were divided into four subgroups; high myopia with glaucoma (MG, 67 eyes of 46 subjects), glaucoma without high myopia (G, 22 eyes of 13 subjects), high myopia without glaucoma (M, 35 eyes of 29 subjects), and a control group with neither glaucoma nor high myopia (C, 35 eyes of 20 subjects). The LC defects were identified and located using a standardized protocol in serial horizontal OCT scans. The prevalence rates of the defects were compared among the groups. Demographic and ocular factors were compared between eyes with and without defects.

Results

LC defects were observed in one eye (0.03%) in the C group, 8 eyes (22.9%) in the M group, 11 eyes (50%) in the G group, and 28 eyes (41.8%) in the MG group. The prevalence rates of the defects differed significantly among the groups (P = 0.0009). Most eyes with defects in the G and MG groups (79.5%) had damage in the corresponding visual hemifields. Other factors such as visual acuity, intraocular pressure, axial length, refractive error, disc ovality, or parapapillary atrophy area did not differ significantly between eyes with and without LC defects.

Conclusions

High myopia and glaucoma significantly increased the risk of LC damage. The LC damage in non-glaucomatous highly myopic eyes may at least partly explain the increased risk of developing glaucoma in myopic eyes.  相似文献   
915.

Background

Glycosylation is an important and universal post-translational modification for many proteins, and regulates protein functions. However, simple and rapid methods to analyze glycans on individual proteins have not been available until recently.

Methods/Principal Findings

A new technique to analyze glycopeptides in a highly sensitive manner by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using the liquid matrix 3AQ/CHCA was developed recently and we optimized this technique to analyze a small amount of transmembrane protein separated by SDS-PAGE. We used the MALDI-MS method to evaluate glycosylation status of membrane-type 1 matrix metalloproteinase (MT1-MMP). O-glycosylation of MT1-MMP is reported to modulate its protease activity and thereby to affect cancer cell invasion. MT1-MMP expressed in human fibrosarcoma HT1080 cells was immunoprecipitated and resolved by SDS-PAGE. After in-gel tryptic digestion of the protein, a single droplet of the digest was applied directly to the liquid matrix on a MALDI target plate. Concentration of hydrophilic glycopeptides within the central area occurred due to gradual evaporation of the sample solution, whereas nonglycosylated hydrophobic peptides remained at the periphery. This specific separation and concentration of the glycopeptides enabled comprehensive analysis of the MT1-MMP O-glycosylation.

Conclusions/Significance

We demonstrate, for the first time, heterogeneous O-glycosylation profile of a protein by a whole protein analysis using MALDI-MS. Since cancer cells are reported to have altered glycosylation of proteins, this easy-to-use method for glycopeptide analysis opens up the possibility to identify specific glycosylation patterns of proteins that can be used as new biomarkers for malignant tumors.  相似文献   
916.

Background

Recent studies have revealed relative frequency and characteristic phenotype of two major causative factors for Silver-Russell syndrome (SRS), i.e. epimutation of the H19-differentially methylated region (DMR) and uniparental maternal disomy 7 (upd(7)mat), as well as multilocus methylation abnormalities and positive correlation between methylation index and body and placental sizes in H19-DMR epimutation. Furthermore, rare genomic alterations have been found in a few of patients with idiopathic SRS. Here, we performed molecular and clinical findings in 138 Japanese SRS patients, and examined these matters.

Methodology/Principal Findings

We identified H19-DMR epimutation in cases 1–43 (group 1), upd(7)mat in cases 44–52 (group 2), and neither H19-DMR epimutation nor upd(7)mat in cases 53–138 (group 3). Multilocus analysis revealed hyper- or hypomethylated DMRs in 2.4% of examined DMRs in group 1; in particular, an extremely hypomethylated ARHI-DMR was identified in case 13. Oligonucleotide array comparative genomic hybridization identified a ∼3.86 Mb deletion at chromosome 17q24 in case 73. Epigenotype-phenotype analysis revealed that group 1 had more reduced birth length and weight, more preserved birth occipitofrontal circumference (OFC), more frequent body asymmetry and brachydactyly, and less frequent speech delay than group 2. The degree of placental hypoplasia was similar between the two groups. In group 1, the methylation index for the H19-DMR was positively correlated with birth length and weight, present height and weight, and placental weight, but with neither birth nor present OFC.

Conclusions/Significance

The results are grossly consistent with the previously reported data, although the frequency of epimutations is lower in the Japanese SRS patients than in the Western European SRS patients. Furthermore, the results provide useful information regarding placental hypoplasia in SRS, clinical phenotypes of the hypomethylated ARHI-DMR, and underlying causative factors for idiopathic SRS.  相似文献   
917.
Hatano high- and low-avoidance (HAA and LAA) rats have been genetically selected on the basis of their two-way active avoidance behavior, and have been shown to differ in other behavioral and hormonal parameters. Since close interconnections among the nervous, endocrine and immune systems have been well documented, these two strains might possess differences in aspects of immunological action. In Experiment 1, plasma levels of IgG, IgM, complement 3 (C3), classical pathway hemolytic complement (CH50) and beta(2)-microglobulin were compared between males of the two strains at 5 and 24 weeks of age. Plasma levels of IgG and CH50 were lower in LAA than HAA rats at 5 weeks of age, whereas those differences disappeared at 24 weeks of age. There were no differences between the two strains in plasma levels of IgM, C3 and beta(2)-microglobulin. In Experiment 2, antibody production to sheep red blood cells (SRBC) and mitogen-induced lymphocyte proliferation were compared between 12-week-old males of the two strains. Antibody responses in the PFC assay, plasma anti-SRBC-IgM levels and spleen weights were higher in LAA than HAA rats. LPS-induced lymphocyte proliferation was greater in LAA than HAA rats. It was concluded that HAA rats show earlier development of immunological development, but that antibody production and mitotic response of B lymphocytes may be more pronounced in adult LAA than HAA rats. The strain differences observed in the immunological response may indicate the usefulness of using Hatano rats in studies of behavioral-immunological relationships.  相似文献   
918.
Dresden G protein-coupled receptor (D-GPCR) is one of orphan G protein-coupled receptors (GPCR). Here we report the identification of the ligands and the characterization of D-GPCR. We investigated over 5000 compounds to evoke the response mediated by D-GPCR and identified 3-methyl-valeric acid and 4-methyl-valeric acid as agonists using a cAMP assay. It is of interest that they dramatically enhanced the intracellular cAMP accumulation and the CRE-luciferase activity in CHO-K1 cells and HEK293 cells expressing the chimeric protein of D-GPCR with a rhodopsin-tag at its N-terminus. Our results established new characteristics of D-GPCR as an olfactory receptor. First, agonists of D-GPCR belong to odorants. Second, D-GPCR mRNA is expressed in the olfactory bulb. In addition, D-GPCR was reported to have similar sequences and its genome locus nearby other olfactory receptors. These results suggest D-GPCR is an olfactory receptor.  相似文献   
919.
Enterostatin (APGPR) is a pentapeptide released from its precursor protein, procolipase. We found for the first time that enterostatin has memory-enhancing activity. Enterostatin enhanced memory consolidation after central or oral administration at a dose of 10 nmol/mouse or 300 mg/kg, respectively, in a step-through type passive avoidance test in mice. The memory-enhancing activity of enterostatin was inhibited by pretreatment with lorglumide, an antagonist for cholecystokinin 1 (CCK1) receptor. However, enterostatin had no affinity for CCK receptors. These results suggest that enterostatin improves memory retention through CCK release.  相似文献   
920.
An Aspergillus saitoi protease preparation, Molsin, was found to contain beta-glucosidase as well as protease activities. Application of Molsin to soybean curd improved its functionality by converting the contained isoflavone glycosides to their aglycones through beta-glucosidase, and also modified the rheological property into a creamy consistency through protease. The enzymatically modified soybean curd was characterized by a ductility flow having no particular rupture point.  相似文献   
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