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p53 point mutations in primary human gastric carcinomas   总被引:12,自引:0,他引:12  
Summary p53 point mutations in primary gastric carcinomas were analyzed by performing cDNA deoxynucleotide sequencing of the gene. Out of 16,9 (56.3%) primary gastric carcinoma cases, including early cancer, showed one or more p53 point mutations in their open-reading frame, and 4 out of 9 cases had a p53 point mutation within highly conserved domains. The characteristics of the p53 mutation spectrum observed in primary tumors were (a) frequent mutation at an A:T pair (50%, 7 out of 14 mutations), (b) high transversion incidence (29%, 4 out of 14 mutations), (c) no transition at CpG, and (d) no G:C to T:A transversion. Our results suggest that p53 mutation is a common event in gastric carcinoma occurring from the early stage of progression with its specific mutation spectrum.Abbreviation PCR-SSCP polymerase chain reaction single-strand conformation polymorphism  相似文献   
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We report a case of a ruptured aneurysm in the anterior superior pancreaticoduodenal artery (PDA) with hypovolemic shock managed successfully by superselective transcatheter arterial embolization of the aneurysm. A75-year-old male presented to our hospital with hematemesis and melena. On admission, he was in shock. Angiography showed an aneurysm about 1?cm in diameter in the anterior superior PDA. However, extravasation of contrast medium was not seen owing to hypovolemic shock. A catheter was inserted into the aneurysm, and superselective microcoil embolization of the PDA aneurysm was successfully achieved. After the microcoil was inserted into the aneurysm itself, it was observed that duodenal vascularity and pancreaticoduodenal arcades were preserved and aneurysm was not present. There was no complication such as necrosis or abscess formation in the pancreas. The patient recovered and is doing well after 18 months of follow-up. Superselective transcatheter arterial embolization should be considered as the initial treatment of choice for all peripancreatic aneurysms.  相似文献   
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The brain tends to associate specific features of stimuli across sensory modalities. The pitch of a sound is for example associated with spatial elevation such that higher-pitched sounds are felt as being “up” in space and lower-pitched sounds as being “down.” Here we investigated whether changes in the pitch of sounds could be effective for visual motion perception similar to those in the location of sounds. We demonstrated that only sounds that alternate in up/down location induced illusory vertical motion of a static visual stimulus, while sounds that alternate in higher/lower pitch did not induce this illusion. The pitch of a sound did not even modulate the visual motion perception induced by sounds alternating in up/down location. Interestingly, though, sounds alternating in higher/lower pitch could become a driver for visual motion if they were paired in a previous exposure phase with vertical visual apparent motion. Thus, only after prolonged exposure, the pitch of a sound became an inducer for upper/lower visual motion. This occurred even if during exposure the pitch and location of the sounds were paired in an incongruent fashion. These findings indicate that pitch–space correspondence is not so strong to drive or modulate visual motion perception. However, associative exposure could increase the saliency of pitch–space relationships and then the pitch could induce visual motion perception by itself.  相似文献   
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Kaposi's sarcoma‐associated herpesvirus (KSHV), the etiologic agent of Kaposi's sarcoma, causes malignancies frequently in patients with acquired immunodeficiency syndrome. In the United States and Europe, KSHV infection is common among men who have sex with men. However, the seroprevalence of KSHV among men who have sex with men in Japan is unknown. In the present study, the seroprevalence of KSHV was investigated among 230 men who have sex with men and 400 age‐ and area of residence‐matched men (controls) using a mixed‐antigen (KSHV‐encoded K8.1, open reading frame 59, 65, and 73 proteins) enzyme‐linked immunosorbent assay and an immunofluorescence assay. Among the Japanese men who have sex with men, serological assays revealed that 27 (11.7%) were seropositive for KSHV; 20 (5%) of the men in the control group were also KSHV seropositive. The seroprevalence of KSHV among men who have sex with men was significantly higher than in the control group (odds ratio = 2.52, 95% confidence intervals = 1.38–4.62, P = 0.0019, Chi‐square test). Infection with the human immunodeficiency virus, Treponema pallidum, or hepatitis B and C virus did not correlate with KSHV infection. Furthermore, the association of KSHV seropositivity with specific sexual activities was not statistically significant. In conclusion, a higher KSHV seroprevalence was found among Japanese men who have sex with men than among the controls, suggesting that the circulation of KSHV infection is more efficient among men who have sex with men in Japan than among men who do not engage in such sexual activities. J. Med. Virol. 85: 1046–1052, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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BackgroundAnti-inflammatory therapy targeting interleukin (IL)-1β reduced cardiovascular events in a randomized trial. We evaluated the relationship between IL-1β mRNA expression in epicardial adipose tissue (EAT) and clinically-assessed coronary atherosclerosis on computed tomography (CT).MethodsWe studied 45 patients before cardiac surgery (coronary artery bypass grafting [CABG], n ?= ?18; non-CABG, n ?= ?27). EAT volume, the coronary calcium score (CCS), and the presence of non- and/or partially-calcified coronary plaques (NCPs) and high-risk coronary plaques (HRPs; minimum CT density <30 Hounsfield units and vascular remodeling index >1.1) on CT angiography were assessed. EAT samples were obtained during cardiac surgery. IL-1β mRNA expression in EAT was measured using quantitative real-time PCR and normalized to that of β-actin in each patient.ResultsThere was no difference in IL-1β mRNA levels between patients who were scheduled for CABG and non-CABG surgery or among subgroups based on the CCS. However, patients with NCPs (median [interquartile range], 4.1[2.0-11.6]E-4 versus 1.8[0.6-4.5]E-4, p ?= ?0.024) and HRP (7.6[3.0-20.4]E-4 versus 1.9[0.7-4.3]E-4, p ?= ?0.0023) had higher IL-1β mRNA levels than those without these plaques. On multivariate analysis adjusted for age, sex, coronary risk factors, statin therapy, CCS, and EAT volume, the presence of HRPs was significantly correlated with elevated IL-1β mRNA levels in EAT (β ?= ?0.39, p ?= ?0.047).ConclusionOur data suggest a contribution of EAT to coronary atherosclerosis through molecular behavior, such as IL-1β gene expression, which may be a new therapeutic target.  相似文献   
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Motor imagery is defined as an act wherein an individual contemplates a mental action of motor execution without apparent action. Mental practice executed by repetitive motor imagery can improve motor performance without simultaneous sensory input or overt output. We aimed to investigate cerebral hemodynamics during motor imagery and motor execution of a self-feeding activity using chopsticks. This study included 21 healthy right-handed volunteers. The self-feeding activity task comprised either motor imagery or motor execution of eating sliced cucumber pickles with chopsticks to examine eight regions of interest: pre-supplementary motor area, supplementary motor area, bilateral prefrontal cortex, premotor area, and sensorimotor cortex. The mean oxyhemoglobin levels were detected using near-infrared spectroscopy to reflect cerebral activation. The mean oxyhemoglobin levels during motor execution were significantly higher in the left sensorimotor cortex than in the supplementary motor area and the left premotor area. Moreover, significantly higher oxyhemoglobin levels were detected in the supplementary motor area and the left premotor area during motor imagery, compared to motor execution. Supplementary motor area and premotor area had important roles in the motor imagery of self-feeding activity. Moreover, the activation levels of the supplementary motor area and the premotor area during motor execution and motor imagery are likely affected by intentional cognitive processes. Levels of cerebral activation differed in some areas during motor execution and motor imagery of a self-feeding activity. This study was approved by the Ethical Review Committee of Nagasaki University(approval No. 18110801) on December 10, 2018.  相似文献   
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