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51.

Background

Posttraumatic pseudoaneurysms (PAs) have been recognized as the cause of delayed hemorrhage complicated with nonoperative management (NOM), although the need for intervention in patients with small-sized PAs and the relationship between the occurrence of PAs and bed-rest has been also unclear.

Objectives

The purpose of this study was to investigate the clinical history of small-sized PAs (less than 10 mm in diameter) which occurred in abdominal solid organs, and to analyze the relationship between the occurrence of PAs and early mobilization from bed.

Methods

Sixty-two patients who were successfully managed with NOM were investigated. Mobilization within three days post-injury was defined as “early mobilization” and bed-rest lasting over three days was defined as “late mobilization.” A comparison of the clinical factors, including the duration of bed-rest between patients with and without PAs detected by follow-up CT was performed. Furthermore, a multiple logistic regression model analysis on the occurrence of PAs was performed.

Results

PAs were detected in 7 of the 62 patients. The One patient with PAs measuring larger than 10 mm received trans-arterial embolization, and the remaining six patients with PAs smaller than 10 mm were managed conservatively. Consequently, no delayed hemorrhage occurred, and the PAs spontaneously disappeared in all of the six patients managed without intervention. The multiple regression model analysis revealed that early mobilization was not a significant factor predicting new-onset PAs.

Conclusions

Small PAs can be expected to disappear spontaneously. Moreover, early mobilization is not a significant risk factor for the occurrence of PAs.  相似文献   
52.

Background & Aims

It has been suggested that amino acid (aa) substitution at position 70 from arginine (70R) to glutamine (70Q) in the genotype 1b hepatitis C virus (HCV) core protein is associated with insulin resistance and worse prognosis. However, the precise mechanism is still unclear. The aim of this study was to investigate the impact of the substitution at position 70 in HCV core protein on adipokine production by murine and human adipocytes.

Methods

The influence of treatment with HCV core protein (70R or 70Q) on adipokine production by both 3T3-L1 and human adipocytes were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and triglyceride content was also analyzed. The effects of toll-like receptor (TLR)2/4 inhibition on IL-6 production by 3T3-L1 induced by HCV core protein were examined.

Results

IL-6 production was significantly increased and adiponectin production was reduced without a change in triglyceride content by treatment with 70Q compared to 70R core protein in both murine and human adipocytes. IL-6 induction of 3T3-L1 cells treated by 70Q HCV core protein was significantly inhibited with anti-TLR2 antibody by 42%, and by TLR4 inhibitor by 40%.

Conclusions

Our study suggests that extracellular HCV core protein with substitution at position 70 enhanced IL-6 production and reduced adiponectin production from visceral adipose tissue, which can cause insulin resistance, hepatic steatosis, and ultimately development of HCC.  相似文献   
53.
ABSTRACT. Here we report a genetically confirmed case of Creutzfeldt-Jakob disease with a prion protein gene codon 180 mutation presenting atypical magnetic resonance imaging findings. The present case exhibited an acute onset and lateralized neurologic signs, and progressive cognitive impairment. No myoclonus or periodic synchronous discharges on electroencephalography were observed. Diffusion-weighted images revealed areas of high signal intensity in the right frontal and temporal cortices at onset that extended to the whole cortex and basal ganglia of the right cerebral hemisphere at 3 months. Although the cerebrospinal fluid (CSF) was initially negative for neuron specific enolase, tau protein, 14–3–3 protein, and abnormal prion protein, the CSF was positive for these brain-derived proteins at 3 months after onset.  相似文献   
54.
The newly characterized cytokine IL-38 (IL-1F10) belongs to the IL-1 family of cytokines. Previous work has demonstrated that IL-38 inhibited Candida albicans-induced IL-17 production from peripheral blood mononuclear cells. However, it is still unclear whether IL-38 is an inflammatory or an anti-inflammatory cytokine. We generated anti-human IL-38 monoclonal antibodies in order to perform immunohistochemical staining and an enzyme-linked immunosorbent assay. While human recombinant IL-38 protein was not cleaved by recombinant caspase-1, chymase, or PR3 in vitro, overexpression of IL-38 cDNA produced a soluble form of IL-38 protein. Furthermore, immunohistochemical analysis showed that synovial tissues obtained from RA patients strongly expressed IL-38 protein. To investigate the biological role of IL-38, C57BL/6 IL-38 gene-deficient (?/?) mice were used in an autoantibody-induced rheumatoid arthritis (RA) mouse model. As compared with control mice, IL-38 (?/?) mice showed greater disease severity, accompanied by higher IL-1β and IL-6 gene expression in the joints. Therefore, IL-38 acts as an inhibitor of the pathogenesis of autoantibody-induced arthritis in mice and may have a role in the development or progression of RA in humans.  相似文献   
55.
The infectious agents of the transmissible spongiform encephalopathies are composed of amyloidogenic prion protein, PrPSc. Real-time quaking-induced conversion can amplify very small amounts of PrPSc seeds in tissues/body fluids of patients or animals. Using this in vitro PrP-amyloid amplification assay, we quantitated the seeding activity of affected human brains. End-point assay using serially diluted brain homogenates of sporadic Creutzfeldt–Jakob disease patients demonstrated that 50% seeding dose (SD50) is reached approximately 1010/g brain (values varies 108.79–10.63/g). A genetic case (GSS-P102L) yielded a similar level of seeding activity in an autopsy brain sample. The range of PrPSc concentrations in the samples, determined by dot-blot assay, was 0.6–5.4 μg/g brain; therefore, we estimated that 1 SD50 unit was equivalent to 0.06–0.27 fg of PrPSc. The SD50 values of the affected brains dropped more than three orders of magnitude after autoclaving at 121°C. This new method for quantitation of human prion activity provides a new way to reduce the risk of iatrogenic prion transmission.  相似文献   
56.
Creutzfeldt-Jakob disease (CJD) is a transmissible, fatal, neurodegenerative disease in humans. Recently, various drugs have been reported to be useful in the treatment of CJD; however, for such treatments to be useful it is essential to rapidly and accurately diagnose CJD. 124 CJD patients and 87 with other diseases causing rapid progressive dementia were examined. Cerebral spinal fluid (CSF) from CJD patients was analyzed by 2D-PAGE and the protein expression pattern was compared with that from healthy subjects. One of three CJD-specific spots was found to be fatty acid binding protein (FABP), and heart-type FABP (H-FABP) was analyzed as a new biochemical marker for CJD. H-FABP ELISA results were compared between CJD patients and patients with other diseases (n = 211). Visual readout accuracy of the Rapicheck® H-FABP test panel for CSF was analyzed using an independent measure of CSF H-FABP concentration. The distribution of H-FABP in the brains of CJD patients was examined by immunohistochemistry. ELISA sensitivity and specificity were 90.3% and 92.9%, respectively, and Rapicheck® H-FABP sensitivity and specificity were 87.9% and 96.0%, respectively. ELISA and Rapicheck® H-FABP assays provided comparable results for 14-3-3 protein and total tau protein. Elevated H-FABP levels were associated with an accumulation of abnormal prion protein, astrocytic gliosis, and neuronal loss in the cerebral cortices of CJD patients. In conclusion, Rapicheck® H-FABP of CSF specimens enabled quick and frequent diagnosis of CJD. H-FABP represents a new biomarker for CJD distinct from 14-3-3 protein and total tau protein.  相似文献   
57.
The apicomplexan, obligate intracellular parasite Toxoplasma gondii orally infects humans and animals. The parasites cross the intestinal epithelium, invade leukocytes in the general circulation and then disseminate into the peripheral organs. The mechanism of extravasation of the infected leukocytes, however, remains poorly understood. It is known that adhesion of leukocytes to extracellular matrix (ECM) is an important factor in extravasation, and CD44 and ICAM-1 on the leukocyte surface are known receptors for hyaluronan (HA), an ECM component. In this study, we demonstrated up-regulation of CD44 and ICAM-1 expression on the surface of T. gondii-infected human monocytic THP-1 cells and fresh isolated human monocyte. T. gondii-infected THP-1 cells adhered more efficiently to immobilized HA than did non-infected cells. T. gondii-infected monocytes in the general circulation might preferentially adhere to the ECM and migrate out from blood vessels, so transporting parasites into the peripheral organs.  相似文献   
58.
In adaptive bone remodeling, it is believed that bone cells such as osteoblasts, osteocytes and osteoclasts can sense mechanical stimuli and modulate their remodeling activities. However, the mechanosensing mechanism by which these cells sense mechanical stimuli and transduce mechanical signals into intracellular biochemical signals is still not clearly understood. From the viewpoint of cell biomechanics, it is important to clarify the mechanical conditions under which the cellular mechanosensing mechanism is activated. The aims of this study were to evaluate a mechanical condition, that is, the local strain on the cell membrane, at the initiation point of the intracellular calcium signaling response to the applied mechanical stimulus in osteoblast-like MC3T3-E1 cells, and to investigate the effect of deformation velocity on the characteristics of the cellular response. To apply a local deformation to a single cell, a glass microneedle was directly indented to the cell and moved horizontally on the cell membrane. To observe the cellular response and the deformation of the cell membrane, intracellular calcium ions and the cell membrane were labeled using fluorescent dyes and simultaneously observed by confocal laser scanning microscopy. The strain distribution on the cell membrane attributable to the applied local deformation and the strain magnitude at the initiation point of the calcium signaling responses were analyzed using obtained fluorescence images. From two-dimensionally projected images, it was found that there is a local compressive strain at the initiation point of calcium signaling. Moreover, the cellular response revealed velocity dependence, that is, the cells seemed to respond with a higher sensitivity to a higher deformation velocity. From the viewpoint of cell biomechanics, these results provide us a fundamental understanding of the mechanosensing mechanism of osteoblast-like cells.  相似文献   
59.
The NET [noradrenaline (norepinephrine) transporter], an Na+/Cl--dependent neurotransmitter transporter, has several isoforms produced by alternative splicing in the C-terminal region, each differing in expression and function. We characterized the two major isoforms of human NET, hNET1, which has seven C-terminal amino acids encoded by exon 15, and hNET2, which has 18 amino acids encoded by exon 16, by site-directed mutagenesis in combination with NE (noradrenaline) uptake assays and cell surface biotinylation. Mutants lacking one third or more of the 24 amino acids encoded by exon 14 exhibited neither cell surface expression nor NE uptake activity, with the exception of the mutant lacking the last eight amino acids of hNET2, whose expression and uptake resembled that of the WT (wild-type). A triple alanine replacement of a candidate motif (ENE) in this region mimicked the influences of the truncation. Deletion of either the last three or another four amino acids of the C-terminus encoded by exon 15 in hNET1 reduced the cell surface expression and NE uptake, whereas deletion of all seven residues reduced the transport activity but did not affect the cell surface expression. Replacement of RRR, an endoplasmic reticulum retention motif, by alanine residues in the C-terminus of hNET2 resulted in a similar expression and function compared with the WT, while partly recovering the effects of the mutation of ENE. These findings suggest that in addition to the function of the C-terminus, the common proximal region encoded by exon 14 regulates the functional expression of splice variants, such as hNET1 and hNET2.  相似文献   
60.
In this study, in addition to the karyotype analysis, the chromosomal distributions of 5 S and 18 S rDNAs, and the Arabidopsis-type (T3AG3) telomeric sequences were detected by means of fluorescence in situ hybridization (FISH) to promote the information of chromosomal organization and evolution in the cultivated lettuce and its wild relatives, L. sativa, L. serriola, L. saligna and L. virosa. The karyotype analysis revealed the dissimilarity between L. virosa and the remaining species. In all four Lactuca species studied, one 5 S rDNA and two 18 S rDNA loci were detected. The simultaneous FISH of 5 S and 18 S rDNAs revealed that both rDNA loci of L. sativa, L. serriola and L. saligna were identical, however, that of L. virosa was different from the other species. These analyses indicate the closer relationships between L. sativa/L. serriola and L. saligna rather than L. virosa. Arabidopsis-type telomeric sequences were detected at both ends of their chromatids of all chromosomes not in the other regions. This observation suggests the lack of telomere-mediated chromosomal rearrangements among the Lactuca chromosomes.  相似文献   
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