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91.
Ririko Takeda Takeshi Ogura Hidetoshi Ooigawa Goji Fushihara Shin-ichiro Yoshikawa Daisuke Okada Ryuichiro Araki Hiroki Kurita 《Clinical neurology and neurosurgery》2013
Objective
Early hematoma expansion is a known cause of morbidity and mortality in patients with intracerebral hemorrhage (ICH). The goal of this study was to identify clinical predictors of ICH growth in the acute stage.Materials and methods
We studied 201 patients with acute (<6 h) deep ganglionic ICH. Patients underwent CT scan at baseline and hematoma expansion (>33% or >12.5 ml increase) was determined on the second scan performed within 24 h. Fourteen clinical and neuroimaging variables (age, gender, GCS at admission, hypertension, diabetes mellitus, kidney disease, stroke, hemorrhagic, antiplatelet use, anticoagulant use, hematoma density heterogeneity, hematoma shape irregularity, hematoma volume and presence of IVH) were registered. Additionally, blood pressure was registered at initial systolic BP (i-SBP) and systolic BP 1.5 h after admission (1.5 h-SBP). The discriminant value of the hematoma volume and 1.5 h-SBP for hematoma expansion were determined by the receiver operating characteristic (ROC) curves. Factors associated with hematoma expansion were analyzed with multiple logistic regression.Results
Early hematoma expansion occurred in 15 patients (7.0%). The cut-off value of hematoma volume and 1.5 h-SBP were determined to be 16 ml and 160 mmHg, respectively. Hematoma volume above 16 ml (HV > 16) ([OR] = 5.05, 95% CI 1.32–21.36, p = 0.018), hematoma heterogeneity (HH) ([OR] = 7.81, 95% CI 1.91–40.23, p = 0.004) and 1.5 h-SBP above 160 mmHg (1.5 h-SBP > 160) ([OR] = 8.77, 95% CI 2.33–44.56, p = 0.001) independently predicted ICH expansion. If those three factors were present, the probability was estimated to be 59%.Conclusions
The presented model (HV > 16, HH, 1.5 h-SBP > 160) can be a practical tool for prediction of ICH growth in the acute stage. Further prospective studies are warranted to validate the ability of this model to predict clinical outcome. 相似文献92.
PVA hydrogels with anisotropic structures have many biomedical applications; however, the hydrophilicity of PVA nanofibers degrades their mechanical properties, and the residual unreacted chemical crosslinkers are disadvantageous for medical use. Therefore, maintaining the stability of aqueous solutions without using crosslinkers is essential while synthesizing electrospun anisotropic PVA nanofibers. Herein, we developed a novel fabrication method for synthesizing tough, anisotropic, and chemical-crosslinker-free nanofibrous cryogels composed of poly(vinyl alcohol) (PVA) and glycerol (Gly) via electrospinning in conjunction with freeze–thawing treatment. Wide-angle X-ray diffraction, attenuated total reflection Fourier-transform infrared spectroscopy, and differential scanning calorimetry analysis revealed an enhanced crystallinity of the PVA and hydrogen bonds in the PVA/Gly nanofibers after freeze–thawing, thereby leading to improved stability of the PVA/Gly nanofiber in water. The scanning electron microscopy observation and tensile tests revealed that the addition of Gly improved both the orientation and the mechanical properties. The values of the toughness parallel and vertical to the fiber axis direction were 4.20 ± 0.63 MPa and 2.17 ± 0.27 MPa, respectively, thus revealing the anisotropy of this mechanical property. The PVA/Gly nanofibrous cryogel consisted of physically crosslinked biocompatible materials featuring toughness and mechanical anisotropy, which are favorable for medical applications including tissue engineering.Fabrication of tough, anisotropic, and chemical crosslinker-free nanofibrous cryogels made from poly(vinyl alcohol) and glycerol via electrospinning in conjunction with freeze-thawing treatment which would be favorable for medical applications. 相似文献
93.
The expression of a tight junction (TJ) component protein, claudin-4, in the enteric neurons was investigated in the rat distal colon by immunohistochemistry and RT-PCR. Claudin-4 immunoreactivity was detected in almost all neurofilament-positive enteric neurons both of the submucosal and the myenteric plexuses, and both of the cell bodies and the neurofibers. The immunoreactivity of enteric neurons for claudin-4 was divided into two types: strongly and weakly positive neurons. Especially in the myenteric plexus, the stained neurons were classified by Dogiel's morphological classification of enteric neurons. The strongly stained claudin-4 positive neurons show Dogiel type II morphology, while the weakly stained claudin-4 positive neurons show Dogiel type I morphology. These immunohistochemical data were supported by mRNA expression in the muscle plus submucosa preparation containing the submucosal and myenteric plexuses, as well as mucosa preparation. The physiological function of claudin-4 expressed on enteric neurons is unclear up to now. It is however suggested that claudin-4 expressed on enteric neurons might play roles for the neural activity, for example as insulation between neurofibers. In conclusion, the present study clearly shows that claudin-4 is expressed by enteric neurons. This is the first evidence that the neuron itself expresses the TJ component protein, claudin-4, in the nervous system. 相似文献
94.
95.
Shoji F Yoshino I Takeshita M Sumiyoshi S Sueishi K Maehara Y 《Pathology, research and practice》2007,203(10):745-748
A patient presenting with Pancoast syndrome was definitely diagnosed to have pulmonary leiomyosarcoma. The patient underwent a right upper lobectomy combined with resection of the chest wall, including the 1st to 3rd ribs. The disease recurred rapidly at the local and distant sites. No previous reports about pulmonary sarcoma presenting as a Pancoast tumor were found in the literature. The possibility of primary pulmonary leiomyosarcoma should be considered, and early detection and surgical resection are necessary when a round or oval tumor with necrosis is observed in the apex of the lung. 相似文献
96.
Ishida-Okawara A Nagi-Miura N Oharaseki T Takahashi K Okumura A Tachikawa H Kashiwamura S Okamura H Ohno N Okada H Ward PA Suzuki K 《Experimental and molecular pathology》2007,82(2):220-226
We have established a mouse model which shows the symptoms of coronary arteritis after consecutive injections of CAWS, which is released from Candida albicans. In this study, we examined neutrophil activation in the initial period after CAWS injection intraperitoneally. During 10 min to 16 h after the injection, blood profiles and neutrophil functions were determined. At the same time, levels of inflammatory cytokines and chemokines in plasma were measured. Furthermore, level of ICAM-1 as a marker of lesion in arterial endothelial cells was measured. Counts of the peripheral leukocytes increased immediately after CAWS injection, especially involving neutrophil. In vitro sensitivity of neutrophils to stimuli was enhanced. Moreover, proinflammatory cytokines (IL-1beta, IL-12 and IL-6) increased in plasma initially followed by an increase in IL-10, G-CSF, MIP-2 and soluble ICAM-1. Locally, ICAM-1 message in arterial walls was significantly increased 16 h after CAWS injection. A decrease in C3 levels was observed in plasma, suggesting complement activation and consumption. In summary, neutrophil activation occurred after CAWS injection, followed by complement activation, and production of proinflammatory cytokines chemokines and G-CSF which may be involved in development of coronary arteritis. 相似文献
97.
Koki Inukai Shuji Noguchi Shin-ichiro Kimura Shigeru Itai Yasunori Iwao 《Journal of pharmaceutical sciences》2018,107(9):2514-2518
Macrolide antibiotics are widely used at clinical sites. Clarithromycin (CAM), a 14-membered macrolide antibiotic, was reported to gelate under acidic conditions. Gelation allows oral administration of acid-sensitive CAM without enteric coating by hindering the penetration of gastric fluid into CAM tablets. However, it is unknown whether this phenomenon occurs in other macrolide antibiotics. In this study, we examined the gelation ability of 3 widely used macrolide antibiotics, roxithromycin (RXM), erythromycin A, and azithromycin. The results indicated that not only CAM but also RXM gelated under acidic conditions. Erythromycin A and azithromycin did not gelate under the same conditions. Gelation of RXM delayed the disintegration of the tablet and release of RXM from the tablet. Disintegration and release were also delayed in commercial RXM tablets containing disintegrants. This study showed that 2 of the 4 macrolides gelated, which affects tablet disintegration and dissolution and suggests that this phenomenon might also occur in other macrolides. 相似文献
98.
Shin-ichiro Nitta Mari Hashimoto Yasuhiro Kazuki Shoko Takehara Hiraku Suzuki Mitsuo Oshimura Hidetaka Akita Kan Chiba Kaoru Kobayashi 《The AAPS journal》2018,20(3):61
Cytochrome P450 3A (CYP3A) enzymes metabolize approximately half of all drugs on the market. Since the endogenous compounds 4β-hydroxycholesterol (4β-HC) and 25-hydroxycholesterol (25-HC) are generated from cholesterol via CYP3A enzymes, we examined whether the plasma levels of 4β-HC and 25-HC reflect hepatic CYP3A4 activity by using a CYP3A-humanized mouse model, in which the function of endogenous Cyp3a was genetically replaced by human CYP3A. CYP3A-humanized mice have great advantages for evaluation of the relationship between hepatic CYP3A protein levels and plasma and hepatic levels of 4β-HC and 25-HC. Levels of CYP3A4 protein in the liver microsomes of CYP3A-humanized mice were increased by treatment with pregnenolone-16α-carbonitrile, a CYP3A inducer. Hepatic and plasma levels of 4β-HC and 25-HC normalized by cholesterol were significantly correlated with hepatic CYP3A4 protein levels. In addition, in vitro studies using human liver microsomes showed that the formation of 4β-HC was strongly inhibited by a CYP3A inhibitor, while the inhibitory effect of the CYP3A inhibition on the formation of 25-HC was weak. These results suggested that CYP3A mainly contributed to the formation of 4β-HC in human liver microsomes, whereas other factors may be involved in the formation of 25-HC. In conclusion, the in vivo studies using CYP3A-humanized mice suggest that plasma 4β-HC and 25-HC levels reflect hepatic CYP3A4 activity. Furthermore, taking the results of in vitro studies using human liver microsomes into consideration, 4β-HC is a more reliable biomarker of hepatic CYP3A activity. 相似文献
99.
100.
Yohei Sotsuka Soh Nishimoto Tomoko Tsumano Kenichiro Kawai Hisako Ishise Masao Kakibuchi Ryo Shimokita Taisuke Yamauchi Shin-ichiro Okihara 《Lasers in medical science》2014,29(3):1125-1129
Currently, laser radiation is used routinely in medical applications. For infrared lasers, bone ablation and the healing process have been reported, but no laser systems are established and applied in clinical bone surgery. Furthermore, industrial laser applications utilize computer and robot assistance; medical laser radiations are still mostly conducted manually nowadays. The purpose of this study was to compare the histological appearance of bone ablation and healing response in rabbit radial bone osteotomy created by surgical saw and ytterbium-doped fiber laser controlled by a computer with use of nitrogen surface cooling spray. An Ytterbium (Yb)-doped fiber laser at a wavelength of 1,070 nm was guided by a computer-aided robotic system, with a spot size of 100 μm at a distance of approximately 80 mm from the surface. The output power of the laser was 60 W at the scanning speed of 20 mm/s scan using continuous wave system with nitrogen spray level 0.5 MPa (energy density, 3.8?×?104 W/cm2). Rabbits radial bone osteotomy was performed by an Yb-doped fiber laser and a surgical saw. Additionally, histological analyses of the osteotomy site were performed on day 0 and day 21. Yb-doped fiber laser osteotomy revealed a remarkable cutting efficiency. There were little signs of tissue damage to the muscle. Lased specimens have shown no delayed healing compared with the saw osteotomies. Computer-assisted robotic osteotomy with Yb-doped fiber laser was able to perform. In rabbit model, laser-induced osteotomy defects, compared to those by surgical saw, exhibited no delayed healing response. 相似文献