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81.
We analyzed the serial changes in serum pancreatic enzyme activities by transcatheter arterial embolization (TAE) in 20 hepatoma patients with liver cirrhosis in an attempt to evaluate the incidence of the pancreatic tissue damage by TAE. Serum amylase activities increased in two (10%) cases, elastase 1 levels in six (30%) cases, and trypsin and pancreatic secretory trypsin inhibitor (PSTI) levels in each of five (25%) cases. Consequently, TAE resulted in the elevation of at least more than one serum pancreatic enzyme in eitht (40%) of 20 cases, although none had clinical symptoms related to pancreatitis When the adverse effect on the pancreatic tissue was compared among 6 cases of the superselective TAE and 14 cases of the nonsuperselective TAE, which were perfomed from the segmental and the nonsegmental hepatic arteries, respectively, the elevation of serum pancreatic enzymes was caused only by nonsuperselective TAE, not by superselective TAE. The volumes of Spongel and lipiodol used or the injected doses of the anticancer agent mitomycin C were not different between the two groups. These results indicate that TAE for the treatment of hepatoma frequently causes pancreatic tissue damage, and the position of the inserted catheter tip is very important to avoid the pancreatic tissue damage by TAE.  相似文献   
82.
Transport of new quinolone antibacterial agents (quinolones) at the blood-brain barrier (BBB) was studied in vitro by using immortalized rat brain capillary endothelial cells RBEC1, and in vivo by using the brain perfusion method in rats and multidrug-resistant mdr1a/1b gene-deficient mice. The permeability coefficient of grepafloxacin measured by brain perfusion was increased by an excess of unlabeled grepafloxacin, suggesting a participation of a saturable BBB efflux system. Uptake coefficients of [(14)C]grepafloxacin, [(14)C]sparfloxacin, and [(14)C]levofloxacin by RBEC1 cells at the steady state were increased in the presence of the unlabeled quinolones. The steady-state uptake of [(14)C]grepafloxacin was increased in the presence of various quinolones. Brain distributions of [(14)C]grepafloxacin and [(14)C]sparfloxacin evaluated in terms of the brain-to-plasma free concentration ratio in mdr1a/1b gene-deficient mice were significantly higher than those in wild-type mice, demonstrating an involvement of P-glycoprotein as the efflux transporter. Anionic compounds, including 4, 4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) and genistein, increased the steady-state uptake of [(14)C]grepafloxacin by RBEC1 cells. Because [(14)C]grepafloxacin was transported by multidrug resistance-associated protein (MRP), in MRP1-overexpressing cells and because RBEC1 and primary cultured brain capillary endothelial cells expressed MRP1, this protein may be an additional efflux transporter for quinolones. Furthermore, the permeability coefficient of [(14)C]grepafloxacin across the BBB was increased by DIDS or in the absence of bicarbonate ions in the brain perfusion method. DIDS or bicarbonate ion did not affect MRP1 function. Accordingly, the brain distribution of quinolones is restricted by the action of multiple efflux transporters, including P-glycoprotein, MRP1, and an unknown anion exchange transporter.  相似文献   
83.
A comprehensive approach to understand the mechanical behavior of materials involves costly and time-consuming experiments. Recent advances in machine learning and in the field of computational material science could significantly reduce the need for experiments by enabling the prediction of a material’s mechanical behavior. In this paper, a reliable data pipeline consisting of experimentally validated phase field simulations and finite element analysis was created to generate a dataset of dual-phase steel microstructures and mechanical behaviors under different heat treatment conditions. Afterwards, a deep learning-based method was presented, which was the hybridization of two well-known transfer-learning approaches, ResNet50 and VGG16. Hyper parameter optimization (HPO) and fine-tuning were also implemented to train and boost both methods for the hybrid network. By fusing the hybrid model and the feature extractor, the dual-phase steels’ yield stress, ultimate stress, and fracture strain under new treatment conditions were predicted with an error of less than 1%.  相似文献   
84.

Aim

The enhanced liver fibrosis (ELF) test is a noninvasive method for diagnosing hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). This multicenter cohort study aimed to evaluate the accuracy of the ELF test and compare it with other noninvasive tests in Japan.

Methods

We analyzed 371 Japanese patients with biopsy-proven NAFLD. We constructed area under the receiver operator characteristic curves (AUROC) to determine the diagnostic accuracies of the ELF test, the Mac-2-binding protein glycosylation isomer (M2BPGi), the Fibrosis-4 (FIB-4) index, and combinations of these indices.

Results

In patients with F0/F1/F2/F3/F4 fibrosis, the median values of the ELF test were 8.98/9.56/10.39/10.92/11.41, respectively. The AUROCs of the ELF test for patients with F0 versus F1–4, F0–1 versus F2–4, F0–2 versus F3–4, and F0–3 versus F4 fibrosis were 0.825/0.817/0.802/0.812, respectively. The AUROCs of the ELF test were greater than those of the FIB-4 index and M2BPGi at each fibrosis stage. Respective low and high cut-off values yielded sensitivities and specificities for predicting advanced fibrosis (≥F3) of 91.1% and 50.8%, and 38.5% and 92.8%, respectively. For F3 or F4 fibrosis, the combined values from the ELF test and FIB-4 index showed a sensitivity of 98.5%, and the combined values from the ELF test and M2BPGi assay showed a specificity of 97.5%.

Conclusions

In Japan, the ELF test predicts NAFLD-related fibrosis from its early stages. The diagnostic ability of the ELF test was not inferior to that of other indices, and the combined values of ELF plus other indices were more accurate.  相似文献   
85.
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87.
In this study, we compared a recently developed PCR-restriction fragment length polymorphism (PCR-RFLP) assay with pulsed-field gel electrophoresis (PFGE) using three different Shiga toxin-producing Escherichia coli (STEC) strains to understand whether repeated subculture in vitro and prolonged storage at room temperature affect the RFLP patterns of STEC. The PFGE profiles of the STEC strains changed by 1 to 8 fragments after repeated subculture and prolonged storage; one strain was no longer clonal after repeated subculture compared to the original isolate according to the Tenover criteria. In contrast, RFLP patterns obtained by PCR-RFLP were identical after repeated subculture and prolonged storage. These data clearly indicate that the PCR-RFLP assay which is based on the diversity of region V, a regulatory region of Stx-phage, was not affected by repeated subculture and prolonged storage and is a more practical and reliable method for molecular typing of STEC strains.  相似文献   
88.
Plectin is a linker protein that interacts with intermediate filaments and β4 integrin in hemidesmosomes of the epidermal basement membrane zone (BMZ). Type XVII collagen (COL17) has been suggested as another candidate plectin binding partner in hemidesmosomes. Here, we demonstrate that plectin–COL17 binding helps to maintain epidermal BMZ organization. We identified an epidermolysis bullosa (EB) simplex patient as having markedly diminished expression of plectin and COL17 in skin. The patient is compound heterozygous for sequence variants in the plectin gene (PLEC); one is a truncation and the other is a small in‐frame deletion sequence variant. The in‐frame deletion is located in the putative COL17‐binding domain of plectin and abolishes the plectin–COL17 interaction in vitro. These results imply that disrupted interaction between plectin and COL17 is involved in the development of EB. Our study suggests that protein–protein binding defects may underlie EB in patients with unidentified disease‐causing sequence variants.  相似文献   
89.
Plectin is a cytoskeletal linker protein which has a long central rod and N‐ and C‐terminal globular domains. Mutations in the gene encoding plectin (PLEC) cause two distinct autosomal recessive subtypes of epidermolysis bullosa: EB simplex (EBS) with muscular dystrophy (EBS‐MD), and EBS with pyloric atresia (EBS‐PA). Previous studies have demonstrated that loss of full‐length plectin with residual expression of the rodless isoform leads to EBS‐MD, whereas complete loss or marked attenuation of expression of full‐length and rodless plectin underlies the more severe EBS‐PA phenotype. However, muscular dystrophy has never been identified in EBS‐PA, not even in the severe form of the disease. Here, we report the first case of EBS associated with both pyloric atresia and muscular dystrophy. Both of the premature termination codon‐causing mutations of the proband are located within exon 32, the last exon of PLEC. Immunofluorescence and immunoblot analysis of skin samples and cultured fibroblasts from the proband revealed truncated plectin protein expression in low amounts. This study demonstrates that plectin deficiency can indeed lead to both muscular dystrophy and pyloric atresia in an individual EBS patient. © 2010 Wiley‐Liss, Inc.  相似文献   
90.
Recently, we reported that a centrally acting non-narcotic antitussive (cough suppressant drug), tipepidine produces an antidepressant-like effect in the forced swimming test in rats. Because pharmacological properties of tipepidine apparently differ from those of typical antidepressants developed to date, we speculated that caramiphen, another centrally acting antitussive, has an antidepressant-like effect. That effect of caramiphen was studied in rats using the forced swimming test. Caramiphen at 20 and 40 mg/kg i.p. significantly reduced immobility. At 40 mg/kg i.p., it increased climbing behavior. Even at 40 mg/kg, this drug had no effect on locomotor activity. Results suggest that a centrally acting antitussive possessing inhibition of GIRK channels has an antidepressant-like effect.  相似文献   
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