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The accumulation of abnormal prion protein (PrPSc) produced by the structure conversion of PrP (PrPC) in the brain induces prion disease. Although the conversion process of the protein is still not fully elucidated, it has been known that the intramolecular chemical bridging in the most fragile pocket of PrP, known as the “hot spot,” stabilizes the structure of PrPC and inhibits the conversion process. Using our original structure-based drug discovery algorithm, we identified the low molecular weight compounds that predicted binding to the hot spot. NPR-130 and NPR-162 strongly bound to recombinant PrP in vitro, and fragment molecular orbital (FMO) analysis indicated that the high affinity of those candidates to the PrP is largely dependent on nonpolar interactions, such as van der Waals interactions. Those NPRs showed not only significant reduction of the PrPSc levels but also remarkable decrease of the number of aggresomes in persistently prion-infected cells. Intriguingly, treatment with those candidate compounds significantly prolonged the survival period of prion-infected mice and suppressed prion disease-specific pathological damage, such as vacuole degeneration, PrPSc accumulation, microgliosis, and astrogliosis in the brain, suggesting their possible clinical use. Our results indicate that in silico drug discovery using NUDE/DEGIMA may be widely useful to identify candidate compounds that effectively stabilize the protein.Electronic supplementary materialThe online version of this article (10.1007/s13311-020-00903-9) contains supplementary material, which is available to authorized users.  相似文献   
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目的:分析胃癌大肠转移的X线钡灌肠表现。方法:104例胃癌入院术前检查发现结肠转移或胃癌术后转移入院治疗的病例。分析钡灌肠初次发现大肠转移征象的年龄、发现胃癌原发病变距初次发现大肠转移的间隔时间、转移病变的发生部位和病变造成的X线钡灌肠图像上的肠管变形和粘膜面的改变。结果:104例胃癌结肠转移,男67例,女37例。胃癌术前检查中发现结肠转移者32例,术后发现的大肠转移中,多数转移发生在手术后3年内(占91.3%)。胃癌原发灶的肉眼形态BorrmannⅢ型(28例)和BorrmannⅣ型(65例)者占89.4%,组织学中以低分化腺癌和印戒细胞癌为主要成分者占91.3%。X线钡灌肠检查显示大肠转移的好发部位为横结肠(80),其次为直肠(50)。转移灶可累及多节段肠管,其中横结肠中1/3段(47),横结肠左1/3(44),横结肠右1/3(39)和直肠腹膜返折之上(39)。X线显示肠管单侧变形者227处,双侧变形者96处。黏膜面表现为梳齿状黏膜纹聚集改变253处,颗粒结节状改变23处,外压性改变20处,弥漫性改变62处。结论:胃癌大肠转移的好发部位为横结肠和直肠,结肠黏膜面的梳齿状黏膜纹聚集为胃癌大肠转移的主要X线钡剂灌肠表现。  相似文献   
4.
Changes in the distribution of hyaluronic acid in the developing human retina were investigated histochemically with alcian blue staining and theStreptomyces hyaluronidase digestion method using 56 human embryos and fetuses ranging from 5 to 41 weeks of gestational age. Hyaluronic acid was first detected in the inner layer of the retina at 12 weeks. The site of accumulation extended towards the outer layer by 20 weeks. At the neonatal stage, longitudinal fibers, possibly the processes of Müller cells, were proved to contain hyaluronic acid. These findings suggest that Müller cells produce hyaluronic acid transiently from 12 weeks’ gestation to the neonatal stage.  相似文献   
5.
OBJECTIVE: Immediate loss of thrombomodulin activity in the endothelium of vein grafts has been demonstrated during 90 min exposure to arterial circulation; this loss of activity is ascribed as an important cause of early thrombosis. Conventional ex vivo gene transfection after vein harvest cannot cover this acute period immediately after implantation. We have established a highly efficient non-viral gene therapy protocol utilizing modified transferrin receptor-facilitated gene transfer. Using this technique, we examined whether in vivo thrombomodulin gene therapy, directed to the endothelium of rat veins 2 days prior to grafting, may prevent thromboresistance impairment of vein grafts under simulated arterial circulation. METHODS: Abdomen of SD rat was opened and cationic liposome:transferrin:thrombomodulin gene complexes or the vector without DNAs were applied to the inferior vena cava of rats while blood flow was reduced by proximal and distal clamping. After 2 days, the transfected veins were harvested and thrombomodulin expression and thromboresistance properties determined before and after exposure to an artificial circuit. RESULTS: The trial of gene transfection using variable doses of DNAs confirmed that 7.5 microg of total DNAs was the most efficient quantity for thrombomodulin gene transfection to IVCs, although accompanying an increase of gene expression in other downstream organs. By transfection of the thrombomodulin gene in IVCs, the generation capacity of activated protein C in venous endothelium increased three-fold compared with veins treated with vector alone (P<0.01). Under simulated arterial circulation, perfusion of veins treated with vector alone decreased thrombomodulin activity to 36% of preperfused levels (P<0.01), whereas transfected grafts preserved the activity at normal vein endothelium levels even after perfusion. Consequently, the increase in endothelial thrombin activity induced by simulated arterial circulation was markedly attenuated in transfected veins (P<0.01), while immunohistochemistry confirmed the preservation of endothelial lining. CONCLUSIONS: Transferrin receptor-facilitated in vivo gene transfer to the inferior vena cava resulted in sufficient thrombomodulin gene expression immediately after graft implantation and subsequent maintenance of thromboresistance even after exposure to arterial pressure. Although further studies are needed, the present results suggest the possibility of gene therapy targeting acute phases of vein graft disease.  相似文献   
6.
Since the prevalence and clinical characteristics of young-onset hypertension are still to be elucidated, we performed targeted-screening at an annual university health check-up for two consecutive years. Out of 16,464 subjects in 2003 and 17,032 in 2004 that were aged less than 30 years, 22 and 26 students (all males) exhibited high blood pressure (BP), respectively, on three occasions during casual BP measurements at the Tohoku University Health Center (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively). These students were asked to measure their BP at home, and 9 subjects in total were diagnosed as having essential hypertension (EH). The remaining students were diagnosed as having white coat hypertension (WCH). In 8 out of 9 EH students, their father and/or mother had also been treated with antihypertensive medication. Adjustment by attendance ratio for each BP measurement suggested that the incidence of EH was around 0.1% and that of hypertension (EH and WCH) was around 0.5% in university students aged less than 25 years, since most of the subjects and hypertensive students were between 18 and 24 years old. Body mass index of the EH, which was more than 25 kg/m2 (overweight), was significantly higher than that with WCH. In conclusion, the combination of repeated casual BP measurements and home BP effectively identified young-onset EH. The clinical parameters indicated that male gender, genetic background, and excessive weight were risk factors for young-onset hypertension.  相似文献   
7.
We report on a male patient with Pick disease who had shown severe white matter atrophy and dilatation of the lateral ventricle in the frontal lobe from an early stage. Upon admission to our hospital 2 years after disease onset, the patient showed apathy, and MRI revealed severe atrophy of the cortex and white matter of the frontal lobe. He died at age 74, 11 years after disease onset. Autopsy revealed severe atrophy of the frontal and temporal lobes, severe loss of white matter in the frontal lobe, dilatation of the lateral ventricles, and cortical thinning. Histopathological examination showed severe loss of myelinated fibers in the frontal white matter and severe neuronal loss with gliosis in the frontal and temporal cortices. Many Pick bodies were seen. Our patient had a rare case of Pick disease predominantly affecting the frontal lobe with severe involvement of the white matter from an early stage. This case suggests that myelinated fibers in the white matter as well as cerebral neurons are primarily affected in Pick disease.  相似文献   
8.
OBJECTIVE: The effect of tonicity changes in nebulizer solutions and irrigations on nasal mucosa is not well known. The present study aims to determine the basic mechanism of hypertonic solution on airway epithelial barrier. STUDY DESIGN AND SETTING: We investigated the electrical potential difference (PD) that is influenced by both active transport and the transepithelial electrical resistance of the epithelial mucosa in the human nose in vivo. The short circuit current (SCC) revealed net ion transport across the epithelium in the guinea pig trachea in vitro. Finally, the size dependency of macromolecules across the tracheal mucosa was determined in vitro using FITC-labeled dextrans of different sizes. RESULTS: PD was significantly decreased after topical application of hypertonic solution both in human and in guinea pig nose. SCC was significantly decreased after application of hypertonic solution. The transport of these dextrans from the basolateral to the apical side was not increased significantly after apical application of hypertonic saline. CONCLUSIONS: Hypertonic saline enhances the electrical permeability of the airway epithelial mucosa but not transport of macromolecule in the short term.  相似文献   
9.
A 28-year-old man complaining of myiodesopsia was given a diagnosis of uveitis. Subsequently he complained facial nerve palsy and enlargement of parotid gland. Heerfordt's syndrome was diagnosed based on the results of several examinations. Facial nerve palsy, enlargement of the parotid gland and uveitis were improved by systemic corticosteroid therapy. At present he is receiving systemic corticosteroid therapy, but numbness in the mouth, thought to be the involvement of the trigeminal nerve, remains. Systemic corticosteroid therapy is usually effective for most cases with Heerford's syndrome. On the other hand, there are some cases with the prolonged peripheral nerve involvement despite systemic corticosteroid therapy, as seen in this case. If peripheral nerve involvement is prolonged, it is necessary to consider small-fibre neuropathy as one possible cause.  相似文献   
10.
Serum levels of free insulin-like growth factor (IGF)-I were measured by immunoradiometric assay (IRMA) in fasting sera of 137 normal boys and 120 normal girls aged from 8 to 15 yr to study relationships between free IGF-I levels and ages, total IGF-I, IGF binding protein (IGFBP)-1, IGFBP-3, and acid-labile subunit (ALS) levels. In both sexes, serum free IGF-I levels and the ratios of free IGF-I to total IGF-I were significantly higher in the pubertal age groups than in the prepubertal age groups. Serum levels of free IGF-I showed a significant positive correlation with those of total IGF-I, IGFBP-3 and ALS, while they showed a significant negative correlation with those of IGFBP-1. These observations suggest that increase in serum free IGF-I levels during puberty is caused by a dramatic increase in total IGF-I, rather than IGFBP-3, and a decrease in IGFBP-1. Also, high free IGF-I levels may play an important role in pubertal growth spurt.  相似文献   
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