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11.
Takao Imai Noriaki Takeda Mahito Ito Koji Nakamae Hideki Sakae Hiromu Fujioka Takeshi Kubo 《Otology & neurotology》2006,27(3):362-366
OBJECTIVE: To show the positional nystagmus in a patient who had suffered from benign paroxysmal positional vertigo (BPPV) that was thought to be caused by involvement of the anterior semicircular canal (ASCC) (A-BPPV). STUDY DESIGN: Retrospective case report. SETTING: City hospital. PATIENT: The present study reports a rare case of A-BPPV in a 41-year-old woman. CASE REPORT: The patient is 41-year-old woman who developed a positional vertigo after playing volleyball on March 22, 2005 and consulted our hospital the next day. When left Dix-Hallpike maneuver was performed, she showed a positional nystagmus of which fast phase direction of the torsional component was clockwise while that of the vertical component was downward. We plotted the slow phase eye velocity of the positional nystagmus during the left Dix-Hallpike maneuver on three-dimensional coordinates that showed the axis of the positional nystagmus to be perpendicular to the plane of the right ASCC. CONCLUSION: These results suggested that the patient was suffering from A-BPPV. 相似文献
12.
Mitogenic activity of lipopolysaccharide (LPS), concanavalin A (Con A), phorbol myristate acetate (PMA) and phytohemagglutinin (PHA) were investigated using spleen cells prepared from C57BL/6 mice orally pretreated with one of five kampohozai extracts (Shosaikoto, Daisaikoto, Hochuekkito, Juzendaihoto and Tokishakuyakusan). Shosaikoto and Daisaikoto elevated the mitogenic activity of LPS and reduced those of Con A. The mitogenic activities of PMA and PHA were elevated by low doses of Shosaikoto and Daisaikoto and suppressed by high doses. Juzendaihoto and Tokishakuyakusan showed no effect on the mitogenic activity of LPS and Con A, but increased those of PMA and PHA. Hochuekkito increased the mitogenic activity of LPS, Con A, PMA and PHA. In the absence of mitogens, these five kampohozais showed no mitogenic activity. These results indicate that the kampohozais used in this experiment appear to possess the immunomodulating or immunostimulating activities that might be expected from clinical experiences in Japan and China. 相似文献
13.
Erk pathways negatively regulate matrix mineralization 总被引:1,自引:0,他引:1
Skeletal mineralization is an important step regulating the mechanical properties of the calcified tissues, but molecular events underlying mineralization still remain elusive. We examined the role of extracellular signal-regulated kinase (Erk) pathways in matrix mineralization of osteogenic cells both in vitro and in vivo. Matrix mineralization by preosteocytic MLO-A5 cells and osteoblastic MC3T3-E1 cells was increased by either PD98059 Mek inhibitor treatment or adenovirus vector-mediated dominant negative Ras (Ras(DN)) expression and was suppressed by Erk activation by platelet-derived growth factor (PDGF) treatment or constitutively active Mek1 (Mek(CA)) expression. Administration of adenovirus vectors carrying Ras(DN) gene onto the calvaria of 1-day-old mice increased the mineralization of the tissues, while that of the Mek(CA) adenovirus suppressed it. These results suggest that the Erk pathway is a negative regulator of the matrix mineralization both in vitro and in vivo. 相似文献
14.
Tanaka S 《American journal of nephrology》2007,27(5):466-478
Bone integrity is maintained through a balance between bone formation and bone resorption, and osteoclasts are primary cells involved in bone resorption. Recent studies have revealed an essential role of macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappa-B ligand (RANKL) in the development of osteoclasts, and detailed molecular cascades that induce osteoclast differentiation, activation and apoptosis have been clarified. Osteoclasts are involved in various pathologic conditions, such as osteoporosis, rheumatoid arthritis and tumor-induced bone disease, which are characterized by abnormal bone resorption, and the finding of RANKL has provided us a good therapeutic target for such pathologic conditions. 相似文献
15.
Masayuki Kyomoto Toru Moro Yoshio Takatori Sakae Tanaka Kazuhiko Ishihara 《Clinical orthopaedics and related research》2015,473(3):942-951
Background
Modifying the surface and substrate of a crosslinked polyethylene (CLPE) liner may be beneficial for high wear resistance as well as high oxidative stability and excellent mechanical properties, which would be useful in contributing to the long-term performance of orthopaedic bearings. A grafted poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) layer on a vitamin E-blended crosslinked PE (HD-CLPE[VE]) surface may provide hydrophilicity and lubricity without compromising the oxidative stability or mechanical properties.Questions/purposes
(1) Will the modifications (PMPC grafting and vitamin E blending) affect the lubrication characteristics of the CLPE surface? (2) Will the modifications affect wear resistance? (3) Will the modifications affect fatigue resistance?Methods
We investigated the effects of surface and substrate modifications (PMPC grafting and vitamin E blending) on the wear and fatigue fracture of thin CLPE samples. For each of the untreated and PMPC-grafted CLPE surfaces with and without vitamin E blended (four groups), wettability and lubricity surface analyses were conducted as well as multidirectional wear and impact-to-wear tests using a pin-on-disk testing machine.Results
The water wettability and lubricity (CLPE [mean ± 95% confidence interval]: 23.2° ± 1.8°, 0.005 ± 0.001; HD-CLPE[VE]: 26.0° ± 2.3°, 0.009 ± 0.003) of the PMPC-grafted surfaces were greater (p < 0.001) than that (CLPE: 90.3° ± 1.2°, 0.067 ± 0.015; HD-CLPE[VE]: 90.8° ± 2.0°, 0.063 ± 0.008) of the untreated surface regardless of vitamin E additives. It was observed that the PMPC grafting (CLPE: 0.23 ± 0.06 mg; HD-CLPE[VE]: 0.05 ± 0.10 mg) was associated with reduced gravimetric wear (CLPE: 0.53 ± 0.08 mg, p = 0.004 HD-CLPE[VE]: 0.23 ± 0.07 mg, p = 0.038) in the multidirectional wear test. The PMPC-grafted surface characteristics did not appear to affect the impact fatigue resistance regardless of vitamin E blending.Conclusions
PMPC grafting improved the surface hydrophilicity and lubricity, and it reduced the gravimetric wear in terms of multidirectional sliding. It did not result in differences in terms of the impact-to-unidirectional sliding regardless of vitamin E blending. Further research is needed to evaluate the wear resistance of PMPC-grafted HD-CLPE(VE) in long-term hip simulator tests under normal and severe conditions, which may offer useful clues to the possible performance of these materials in vivo.Clinical Relevance
Our preliminary in vitro findings suggest that some improvement in the wear performance of crosslinked polyethylene acetabular liners in total hip arthroplasty could be obtained using PMPC grafting. Further research is needed to evaluate the wear resistance of PMPC-grafted HD-CLPE(VE) in long-term hip simulator tests under normal and severe conditions, which may offer useful clues to the possible performance of these materials in vivo. 相似文献16.
Yohei Kawaguchi Masayuki Nakao Kenshiro Omura Naoya Iwamoto Hiroki Ozawa Yasuto Kondo Junji Ichinose Yosuke Matsuura Sakae Okumura Mingyon Mun 《Journal of thoracic disease》2020,12(12):7218
BackgroundIt is critical to have an accurate measurement of solid tumor size in order to predict the invasiveness of small lung adenocarcinomas. Some lesions cannot be measured accurately via High-resolution computed tomography (HRCT) due to their irregular shape and unclear borders. For this reason, we evaluated the relative efficacy of three-dimensional (3D) CT for predicting invasive adenocarcinoma.MethodsWe evaluated 195 patients with clinical stage IA adenocarcinomas, including 109 with lesions documented as invasive that were surgically resected at our institute during 2017. All lesions were categorized as either (I) lesions that were difficult to evaluate (i.e., hazy lesions; HL) or (II) more typical lesions (TL). The relationships between solid tumor size as determined by HRCT, solid tumor volume as determined by 3D CT and pathologic diagnosis were evaluated.ResultsFifty-seven patients (29%) were diagnosed with HL. We set the cut-off value for the solid volume at 225 mm3 as predictive for invasive adenocarcinoma. When evaluating all 195 patients as a group, the accuracy, sensitivity, and specificity based on the solid tumor volume were similar to those based on the solid tumor size. When we limit our analysis to the HL group, the specificity based on solid tumor volume (65.5%) was higher than that based on solid tumor size (44.8%) with a difference that approached statistical significance (P=0.070).Conclusions3D CT was equivalent to HRCT for predicting invasive adenocarcinoma and may be particularly useful for diagnosing lesions that are difficult to evaluate on HRCT. 相似文献
17.
Hiroji Shinkawa Shigekazu Takemura Takahiro Uenishi Masayuki Sakae Kazunori Ohata Yorihisa Urata Kazuhisa Kaneda Akinori Nozawa Shoji Kubo 《Surgery today》2013,43(3):276-283
Purpose
Malnutrition has been considered a risk factor for the development of a surgical site infection (SSI). The aim of this study was to determine the relationship between preoperative nutritional screening scores and the development of SSI after pancreaticoduodenectomy.Methods
We examined 64 patients who had undergone pancreaticoduodenectomy. Their clinical data, nutritional risk index (NRI), and nutritional risk screening 2002 (NRS-2002) score were recorded. SSIs were diagnosed according to the definitions of wound infection established by the Center for Disease Control and Prevention and were confirmed by a microbiological examination. Data were analyzed using the Fisher exact probability method and a multivariate logistic regression analysis.Results
SSIs developed in 21 patients (33 %). Eleven patients had wound infections, and 14 patients had an intra-abdominal abscess. A univariate analysis of perioperative factors revealed that a pancreatic fistula, the NRS-2002, and the NRI were significantly associated with the development of SSI (p < 0.05). The multivariate logistic regression analysis revealed that a pancreatic fistula and the NRI were independent risk factors for SSI. By analyzing the pre- and intra-operative factors after excluding the 11 patients with pancreatic fistulas, the NRI was still an independent risk factor for SSI.Conclusion
The present study showed the NRI to be an independent factor for predicting the risk of SSI after pancreaticoduodenectomy. 相似文献18.
Kosuke Uehara Hirotaka Chikuda Yoshimi Higurashi Kiyofumi Ohkusu Katsushi Takeshita Atsushi Seichi Sakae Tanaka 《International journal of surgery case reports》2013,4(12):1107-1109
INTRODUCTIONAbiotrophia species have been referred to as nutritionally variant streptococci because of their fastidious nutritional requirements for growth. Abiotrophia species are difficult to identify with conventional solid culture.PRESENTATION OF CASEA 48-year-old woman was admitted to our hospital with severe low back pain and body temperature of 38.2 °C. Magnetic resonance imaging revealed edema and contrast enhancement of the L4 and L5 vertebral bodies with high signal intensity in the L3-4 and L4-5 intervertebral discs on the T2-weighted images. The patient underwent needle biopsy of the L3-4 disk. Cultures of disk biopsy samples and blood yielded gram positive cocci in short chains with scanty growth on chocolate agar. Further subculture with supplemented medium and subsequent 16S ribosomal RNA gene sequencing identified the pathogen as Abiotrhophia adiacens. The patient was treated with intravenous ampicillin. At 6-month follow-up, the patient was free of symptoms.DISCUSSIONCausative microorganisms remain unidentified in 25–40% of spinal infection cases. Abiotrophia species grow poorly on conventional solid media, and require pyridoxal or thiol group supplementation. Use of Brucella HK agar or GAM agar plate is helpful for detection of Abiotrophia species. We first confirmed the diagnosis by direct identification of Abiotrophia adiacens from infected disk. Abiotrophia species are one of the major pathogens of infective endocarditis accounting for 5% of cases. Considering their fastidious nature, it is likely that most cases of Abiotrophia discitis are falsely classified as culture-negative discitis; therefore, their role in pyogenic discitis may be underestimated.CONCLUSIONSubculture using nutritionally supplemented media is crucial for their identification. 相似文献
19.
Nakada H Sakae T LeGeros RZ LeGeros JP Suwa T Numata Y Kobayashi K 《Implant dentistry》2007,16(3):281-289
PURPOSE: It is now well known that implant surface properties affect osseointegration. Grit-blasting with abrasives and coating by plasma are methods to modify implant surfaces. This study aimed to compare the direction of new bone formation associated with three types of surfaces. MATERIALS AND METHODS: Titanium (Ti) alloy rods grit-blasted with alumina abrasive (Group 1, G1), with apatitic abrasive (Group 2, G2), and with apatitic abrasive and plasma-sprayed with hydroxyapatite (Group 3, G3) were implanted in surgically created defects in tibias of New Zealand white rabbits for 2 and 4 weeks. After sacrifice, the implants and surrounding bones were obtained and analyzed using back scattered imaging. RESULTS: Differences in patterns of bone formation among the groups were observed: originating from the cortical bone towards the implant surface (Type A), surrounding the implant (Type B) and originating from the medullary cavity (Type C). G1 and G3 showed Types A and B while G2 exhibited Types A, B and C. After 4 weeks, greater amount of new bone was observed in G2 group compared with those in G1 and G3 groups. CONCLUSIONS: This study demonstrated that patterns of bone formation are influenced by methods of surface modification. 相似文献
20.
Nagata Kosei Oshima Yasushi Nakamoto Hideki Sakamoto Ryuji Ohtomo Nozomu Izuka Masaaki Nakajima Koji Yoshimoto Takahiko Fujii Tomoko Matsudaira Ko Tanaka Sakae Oka Hiroyuki 《European spine journal》2020,29(6):1435-1444
European Spine Journal - To investigate the psychometric properties of the Japanese version of the Core Outcome Measures Index-Back (COMI-Back), only recently published according to the established... 相似文献