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61.
Yukito Ichinose Hiroshi Asoh Tokujiro Yano Hideki Yokoyama Takashi Inoue Kohsuke Tayama Takashi Ueda Eiji Takai 《Surgery today》1995,25(9):811-815
An experimental study was conducted to determine whether pericardial fat tissue could induce neovascularization and produce cytokines related to tissue repair. Neovascularization was examined using chick chorioallantoic membranes. Pieces of pericardial fat tissue, omentum, and intercostal muscle were individually placed on a number of chorioallantoic membranes and neovascularization induced by each material was assayed 6 days after the implantation. The intensity of neovascularization was in the order of pericardial fat omentum > muscle. Cytokines, such as interleukin 1 (IL-1) and , tumor necrosis factor- (TNF), interferon- (IFN-), and interleukin 6 (IL-6) were assayed in a culture supernatant of pericardial fat tissue. The latter was obtained 24h after the addition of lipopolysaccharide (LPS) following various incubation times. All cytokines other than IFN are known to play a part in tissue repair, whereas IFN is negatively related to tissue repair because it inhibits fibroblast growth. The pericardial fat tissue incubated with LPS produced a certain amount of IL-1 on day 1, and TNF on days 1 and 8, whereafter these values decreased to an undetectable level. Irrespective of the addition of LPS, a large amount of IL-6 was observed in the supernatant of pericardial fat tissue and it was detectable until day 29. On the contrary, INF was not detected at any assay time. These observations suggest that a pericardial fat pad flap could possibly be beneficial in the prevention of bronchopleural fistula after pulmonary resection. 相似文献
62.
Komine Y Tanaka NK Yano R Takai S Yuasa S Shiroishi T Tsuchiya K Yamamori T 《Brain research. Molecular brain research》1999,66(1-2):1-13
We have characterized a novel type of non-coding RNA which consists of tandem repeats of similar sequences, approximately 0.9 kb in size. This RNA, termed Bsr (brain specific repetitive) RNA, is encoded at a single locus (6 q31-->q32) in the rat genome, where 100 to 150 copies of the 0.9 kb sequences are repeated in tandem. Bsr RNA is preferentially expressed in the rat central nervous system (CNS), especially in phylogenetically old structures, such as the pareo- and archicortex, amygdala, thalamus and hypothalamus. In the developing brains, Bsr RNA is expressed in the subsets of differentiating cells but not in proliferating cells. Despite the finding that Bsr RNA appears to be conserved only among the Rattus species, the specific expression pattern of Bsr RNA suggests that it might have some role in the rat CNS. 相似文献
63.
Murata T Omata N Fujibayashi Y Waki A Sadato N Yoshida S Yano R Yoshimoto M Yonekura Y 《Journal of neural transmission (Vienna, Austria : 1996)》1999,106(11-12):1075-1087
Fresh rat brain slices were incubated with 2-deoxy-2-[18F]-fluoro-D-glucose ([18F]FDG) in oxygenated Krebs-Ringer solution at 36 degrees C, and serial two-dimensional time-resolved images of [18F]FDG uptake were obtained from these specimens on imaging plates. The fractional rate constant (= k3*) of [18F]FDG proportional to the cerebral glucose metabolic rate (CMRglc) was evaluated by applying the Gjedde-Patlak graphical method to the image data. With hypoxia loading (oxygen deprivation) or glucose metabolism inhibitors acting on oxidative phosphorylation, the k3* value increased dramatically suggesting enhanced glycolysis. After relieving hypoxia < or = 10-min, the k3* value returned to the pre-loading level. In contrast, with > or = 20-min hypoxia only partial or no recovery was observed, indicating that irreversible neuronal damage had been induced. However, after loading with tetrodotoxin (TTX), the k3* value also decreased but returned to the pre-loading level even after 70-min TTX-loading, reflecting a transient inhibition of neuronal activity. This technique provides a new means of quantifying dynamic changes in the regional CMRglc in living brain slices in response to various interventions such as hypoxia and neurotoxic chemical-loading as well as determining the viability and prognosis of brain tissues. 相似文献
64.
Objectives. To determine whether the number of CAG repeats in the androgen receptor gene is enhanced in patients with idiopathic azoospermia.Methods. Using the polymerase chain reaction, the number of CAG repeats was assayed in 41 patients with idiopathic azoospermia and in 48 normozoospermic fertile men.Results. In the control group, the CAG repeat length ranged from 17 to 30 (mean 23.9 ± 2.9); in the azoospermic group, the CAG repeat length ranged from 20 to 34 (mean 26.5 ± 3.5). The difference between the two groups was statistically significant (P = 0.0013). None of the men in the control group had a CAG repeat length greater than 31; four of the azoospermic men had 34 CAG repeats.Conclusions. Results suggest that an increase in the number of CAG repeats in the androgen receptor gene to 31 or greater may be associated with the etiology of at least some cases of idiopathic azoospermia. 相似文献
65.
Long-term efficacy of immunization against hepatitis B virus in infants at high-risk analyzed by polymerase chain reaction. 总被引:1,自引:0,他引:1
H Kato K Nakata K Hamasaki D Hida H Ishikawa T Aritomi K Nakao Y Kato M Yano K Eguchi 《Vaccine》1999,18(7-8):581-587
Perinatal transmission of hepatitis B virus (HBV) is a common cause of chronic infection. In the present study, we evaluated the long-term efficacy of immunization against HBV in infants at high-risk, by using polymerase chain reaction (PCR). Two hundred and fifty-one infants received hepatitis B immunoglobulin at birth and a course of hepatitis B vaccine within 6 months of age between 1981 and 1993. Of 251 infants, 203 (81%) and 97 (39%) were followed until 1 and 4-6 years of age, respectively. HBV-DNA was detected by PCR in 74 (36%) of 203 children at 1 year of age, while the prevalence rate of children positive for HBV-DNA decreased to 14 (14%) of 97 children at 4-6 years of age, including 2 children who had the breakthrough variants of HBV. Our results indicate that most of HBV infections occur early, during the first year, and that immunization against HBV effectively protects infants at high-risk against viral transmission, at least up to 4-6 years of age. 相似文献
66.
67.
Scopolamine Effects on Visual Information Processing, Attention, and Event-Related Potential Map Latencies 总被引:6,自引:0,他引:6
Daniel Brandeis Hilary Naylor Roy Halliday Enoch Callaway Lovelle Yano 《Psychophysiology》1992,29(3):315-335
We measured performance and event-related brain potential (ERP) map latencies in 12 subjects during four visual discrimination tasks to compare the timing of scopolamine effects on information processing and attention. "Topographic component recognition" found ERP map latencies at times of best fit with a component model map. This "common topography" criterion minimized topographic differences among conditions to facilitate latency interpretations. Scopolamine slowed N1 latency in all tasks, and P3 and reaction time in some tasks. The drug delayed responses to easy targets more than to hard targets. It also induced a disproportionate N1 delay for unilateral high spatial frequency gratings. Both effects reflect a scopolamine-induced impairment when processing targets that usually capture attention. Scopolamine also impaired accuracy for unilateral high spatial frequency gratings, and for gratings presented at probable locations, confirming and extending previous findings. Scopolamine-induced P1 and N1 delays showed that visual processing was affected. Several results were inconsistent with a serial stage model. We suggest that scopolamine both delays selected processes and impairs a processing mode based on automatic capture of attention, inducing more serial processing. 相似文献
68.
An objective and quantitative method for the evaluation of the quality of megavoltage portal images was developed by applying receiver operating characteristic analysis. On the basis of therapeutic use of portal images, setup errors were employed as "signals" in this experimental study that compared the original portal films with digitized images. Six readers observed 104 portal images of a chest phantom, half of which were "abnormal" (ie, had setup errors). Digital images (2,048 x 2,048 matrix) were enhanced by means of histogram equalization and then printed with a laser printer for observation. The readers showed a higher discrimination capacity with the digitally enhanced images, although a statistically significant improvement was not demonstrated. The present method of assessment of image quality proved to be both simple and clinically reasonable. 相似文献
69.
Expression level of valosin-containing protein is strongly associated with progression and prognosis of gastric carcinoma. 总被引:9,自引:0,他引:9
Shinji Yamamoto Yasuhiko Tomita Yoshihiko Hoshida Shuji Takiguchi Yoshiyuki Fujiwara Takushi Yasuda Masahiko Yano Shoji Nakamori Masato Sakon Morito Monden Katsuyuki Aozasa 《Journal of clinical oncology》2003,21(13):2537-2544
PURPOSE: Valosin-containing protein (VCP; also known as p97) was shown to be associated with antiapoptotic function and metastasis via activation of nuclear factor kappa-B signaling pathway. In this study, association of VCP expression with recurrence of gastric carcinoma (GC), in which lymphatic vessels are the main route of spread, was examined. PATIENTS AND METHODS: VCP expression in 330 patients with GC (242 males and 88 females) with ages ranging from 26 to 81 years (median, 60 years) was analyzed by immunohistochemistry, in which staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. RESULTS: Ninety-four (28.7%) patient cases showed level 1 and 233 patient cases (71.3%) showed level 2 VCP expression. Patients with level 2 expression showed higher rates of large tumor size (P <.0001), undifferentiated histologic subtype (P <.05), presence of vascular and lymphatic invasion (P <.0001 for both), presence of lymph node metastasis (P <.0001), deep tumor invasion (P <.0001), and poorer disease-free and overall survivals (P <.0001 for both) compared with those with level 1 VCP expression. Multivariate analysis revealed VCP expression level as an independent prognosticator for disease-free and overall survival. VCP level was an indicator for disease-free and overall survival in the early (pT1; P <.01 and P <.05, respectively) and advanced (pT2-4; P <.05 for both) group of pathologic tumor-node-metastasis system classification. CONCLUSION: The prognostic significance of VCP expression level in GC was demonstrated. 相似文献
70.
Reduced MLH1 expression after chemotherapy is an indicator for poor prognosis in esophageal cancers.
Kentaro Kishi Yuichiro Doki Masahiko Yano Takushi Yasuda Yoshiyuki Fujiwara Syuji Takiguchi Sontae Kim Ichiro Higuchi Morito Monden 《Clinical cancer research》2003,9(12):4368-4375
PURPOSE: Loss of function or expression of the mismatch repair gene MLH1 has been implicated in experimentally acquired resistance to cisplatin (CDDP) and other anticancer agents. The clinical significance of MLH1 expression was evaluated in advanced thoracic squamous cell carcinoma of the esophagus (ESCC) treated by neoadjuvant chemotherapy. EXPERIMENTAL DESIGN: We investigated MLH1 and P53 expression by immunohistochemistry in the surgical specimens of 107 patients who had undergone preoperative chemotherapy using CDDP along with 5-FU and ADM. These findings were correlated with the clinical outcome for this treatment. Biopsy samples before chemotherapy in 20 of these patients, and another 43 surgical specimens without chemotherapy, were also examined as control samples. RESULTS: In surgical specimens of ESCC, low MLH1 expression was not frequent without chemotherapy, whereas it was commonly observed after chemotherapy (14 versus 37%, P = 0.0057). Comparison between samples before and after chemotherapy revealed that MLH1 expression was unchanged during chemotherapy in 12 of 20 patients (60%) but was from high to low in 8 of 20 patients (40%). In the surgical specimen after neoadjuvant chemotherapy, MLH1 expression was not correlated with any clinicopathological factors, including the response to chemotherapy. However, low MLH1 showed poorer prognosis than high MLH1 (5-year survival 40.6 versus 19.3%, P = 0.0393), and in multivariate analysis, MLH1 was an independent prognostic factor for this multimodal treatment, following lymph node metastasis and clinical response to chemotherapy. Positive p53 expression, which was not affected by chemotherapy, was weakly associated with a poor response and clinical outcome, although this trend was not significant. CONCLUSIONS: In advanced ESCC, expression of MLH1 is reduced during CDDP-based chemotherapy, and this may partly account for poor postoperative survival. 相似文献