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1.
K Ohno Y Morotomi K Harumoto M Ueda M Nakahira T Nakamura T Azuma T Moriuchi T Yoshida C Shiokawa T Nakaoka 《Zeitschrift für Kinderchirurgie》2006,16(3):155-159
AIM: Bone scintigraphy was performed to elucidate the effects of the Nuss procedure for pectus excavatum on the bony thorax. METHODS: Eight boys and 6 girls (5 - 24 years of age) underwent bone scintigraphy, using (99m)Tc-HMDP. Eleven patients were studied 5 to 21 days after the Nuss procedure; 6 were studied 20 to 24 months after the operation before bar removal. Three of 14 were studied twice after the Nuss procedure and before bar removal. RESULTS: In the early postoperative phase, RI accumulation was found at the sternum and ribs in only 1 of 6 patients under 9 years of age, whereas in all 5 older patients, RI had accumulated at the sternum. Scintigrams before bar removal revealed, regardless of age, hot spots at the lateral ribs in contact with the bar and at the costochondral junctions where the bar passed through the intercostal spaces. Furthermore, chest roentgenograms showed the deformed lateral ribs in contact with the bar. CONCLUSIONS: The Nuss procedure creates minute fractures at the sternum and the ribs, especially in older patients. The bar deforms the ribs and restrains the growth of the thorax. Furthermore, it constantly rubs against the ribs and can therefore cause late complications. Bone scintigraphy may determine the appropriate timing for bar removal. 相似文献
2.
Kawano S Morotomi T Toyono T Nakamura N Uchida T Ohishi M Toyoshima K Harada H 《Connective tissue research》2002,43(2-3):409-412
Rat incisors grow continuously throughout life. Producing a variety of dental epithelial cells is performed by stem cells located in the cervical loop of the incisor apex. To study the mechanisms for cell differentiation, we established a dental epithelial cell line (HAT-7) originating from a cervical loop epithelium of a rat incisor. Immunochemical studies showed that HAT-7 produced the cells expressing amelogenin, ameloblastin, or alkaline phosphatase (ALP). To illustrate a role of Notch signaling in the determinant of the cell fate, we examined expression patterns of Notch1 and Jagged1 in HAT-7 density dependently. At lower cell density, Notch1- or Jagged1-expressing cells were not seen. However, when they were fully confluent, cells began to express Notch1 or Jagged1 strongly. Some ALP-positive cells were almost consistent with Notch1-expressing cells but not Jagged1-expressing cells. These results suggested that the determinant of direction of differentiation was associated with Notch signaling pathway. 相似文献
3.
Biological properties and gene expression associated with metastatic potential of human osteosarcoma 总被引:4,自引:0,他引:4
Nakano T Tani M Ishibashi Y Kimura K Park YB Imaizumi N Tsuda H Aoyagi K Sasaki H Ohwada S Yokota J 《Clinical & experimental metastasis》2003,20(7):665-674
Lung metastasis has a great influence on the prognosis of patients with osteosarcoma. We previously established two high-metastatic
sublines, M112 and M132, from the HuO9 human osteosarcoma cell line by in vivo selection. In this study, we newly isolated a high-metastatic subline, H3, and three low-metastatic sublines, L6, L12 and
L13, from HuO9 by the dilution plating method. Three high-metastatic sublines produced more than 200 metastatic nodules in
the lung, while three low-metastatic sublines produced no or few nodules after injection of 2 × 106 cells into the tail vein of nude mice. There were significant differences in the motility and invasiveness between high-
and low-metastatic sublines, whereas the growth rates in vitro and the tumorigenicity in vivo showed no correlation with their metastatic abilities. Early adherence to culture plates was significantly lower in two of
three low-metastatic sublines, which occupied smaller surface areas on the culture plates than other sublines did. Comparison
of the expression of 637 cancer-related genes by cDNA microarray revealed that seven genes were differentially expressed between
high- and low-metastatic sublines. Among them, five genes (AXL, TGFA, COLL7A1, WNT5A, and MKK6) were associated with adherence, motility, and/or invasiveness. These results suggest that the differences in motility/invasiveness
and adhesive abilities are key determinants of lung metastasis in osteosarcoma.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Takagi A Matsuzaki T Sato M Nomoto K Morotomi M Yokokura T 《Medical microbiology and immunology》1999,188(3):111-116
The present study was designed to determine whether tumor induction by 3-methylcholanthrene (MC), a carcinogenic hydrocarbon,
can be inhibited by oral administration of Lactobacillus casei strain Shirota (LC). C3H/HeN mice were divided into four groups and assigned to the following treatments: treated with MC
and given control or LC-containing diet; treated with vehicle only and given control or LC-containing diet. MC (1 mg) was
injected intradermally at 7 weeks of age and the tumor incidence was monitored; LC was mixed into a diet at a concentration
of 0.05% (w/w) and the diet was fed from the day of MC injection throughout the study. Spleen cells were analyzed for the
immune parameters at 12 and 16 weeks after the MC injection. Oral feeding of mice with LC reduced tumor incidence (P < 0.05). MC treatment lowered the in vitro response to concanavalin A (Con A) of spleen cells, the secretion of interleukin-2
in spleen cell culture after stimulation of the cells with Con A and the proportions of CD3+, CD4+ and CD8+ splenic cells. However, the analysis of the spleen cells obtained from the mice treated with MC and given the LC-containing
diet revealed that these disrupted host immune parameters were maintained at the level of normal controls. These results suggest
that oral feeding of mice with LC inhibits MC-induced tumorigenesis by modulating the disrupted host immune responses during
MC carcinogenesis.
Received: 14 April 1999 相似文献
5.
Intestinal Enzyme Activities in Germfree, Conventional, and Gnotobiotic Rats Associated with Indigenous Microorganisms 下载免费PDF全文
Various enzyme activities involved in the active transport system, glycolysis, and digestion were assayed in various parts of the gastrointestinal tracts of germfree, conventional, and gnotobiotic rats associated with indigenous bacteria. The activity levels of alkaline phosphatase, glucose 6-phosphatase, adenosine triphosphatase, and disaccharidases in the upper small intestine were highest in all parts of the gastrointestinal tracts of various kinds of gnotobiotic, conventional, and germfree rats. Alkaline phosphatase, glucose 6-phosphatase, and adenosine triphosphatase activities in the upper small intestine of germfree rats were, respectively, 2.3-, 2.9-, and 1.7-fold higher than those in conventional rats. Similar to the results of these enzymes, sucrase, maltase, trehalase, and lactase activities in the upper small intestine of germfree rats were, respectively, 1.6-, 1.5-, 2.3-, and 1.8-fold higher than those in conventional rats. In various gnotobiotic rats, enzyme activity levels were intermediate between those in germfree and conventional rats. These findings suggest that those enzymatic activities are strongly depressed by the association with the indigenous microorganisms in the epithelial mucosa of the upper small intestine of rats. The levels of pyruvate kinase, hexokinase, and lactate dehydrogenase activities were highest, respectively, in the stomach, cecum, and the upper small intestine and cecum in all parts of the gastrointestinal tracts in various kinds of gnotobiotic, conventional, and germfree rats. It was also shown that six kinds of gastrointestinal bacteria, including lactobacilli, significantly depressed the enzyme activity levels to levels between those of the germfree and conventional rats in the upper small intestine of gnotobiotic rats. 相似文献
6.
Distribution of indigenous bacteria in the digestive tract of conventional and gnotobiotic rats. 总被引:9,自引:3,他引:9 下载免费PDF全文
The localization and population levels of the indigenous bacterial flora of conventional rats were investigated by cultural and histological techniques. Lactobacilli predominate in the stomach and upper part of the small intestine and associate with keratinized cells of the nonglandular portion of stomach. Mixtures of varying complexity of pure cultures of indigenous bacteria were inoculated into germfree rats. The distribution of these bacteria was examined to investigate the effect of lactobacilli in controlling the composition of other bacterial species in each portion of the digestive tract. In the stomach and the upper part of the small intestine, lactobacilli controlled the population levels of other bacterial species. In the lower part of the small intestine, not only lactobacilli but also the anaerobes which colonized the large bowel influenced the population levels of other bacterial types. Staphylococci isolated from a conventional rat colonized specifically the keratinized cells of the nonsecreting epithelium of the stomach when the rats were free from lactobacilli. This colonization was not observed after inoculation of lactobacilli into the rats. 相似文献
7.
Giorgadze TA Shiina N Baloch ZW Tomaszewski JE Gupta PK 《Diagnostic cytopathology》2004,31(5):300-306
Amyloid fat pad aspiration specimens for cases with a clinical suspicion of amyloid typically are stained with Congo red and examined by brightfield microscopy. Congophilia with apple-green birefringence by polarization microscopy (PM) is considered diagnostic for amyloid. Examination of Congo red-stained slides by fluorescent microscopy (FM) is considered by some to be a more sensitive detection method. In this study, we assessed the utility of this technique in cytopathology archival slides from abdominal fat pad aspirations previously stained with Congo red dye. Seventy-eight cases of abdominal fat pad aspirations collected during the last 5 yr and stained with the Congo red procedure were obtained from archival files. Additionally, 20 adipose tissue material slides prepared from the surgical pathology specimens were examined as controls. One representative smear was examined in each case using FM equipped with rhodamine excitation/absorption (540/570 nm) filters. Relevant clinical information was obtained in all cases. Twelve cases (15.4%) of the 78 fat pad aspiration cases were reported originally as positive by Congo red stain using polarization and apple-green birefringence as diagnostic criteria. On review, four cases were deemed unsatisfactory. By FM examination 29 of the 74 (39.2%) cases were reclassified as positive for amyloid. The results were confirmed by immunohistochemical stain for amyloid P protein and electron microscopy. A number of similar distinct fluorescence and immunohistochemical patterns were recognized in the positive cases. Minimally weak fluorescence in the adipose tissue was observed in the control cases. The use of FM in Congo red-stained fat pad smears can improve the detection of amyloid in cytology preparations. 相似文献
8.
Shizuya Saika Akira Ooshima Natsuko Hashizume Osamu Yamanaka Sai-ichi Tanaka Yuka Okada Sakae Kobata 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(6):347-353
Background: Minoxidil is an inhibitor of lysyl hydroxylase, an enzyme involved in collagen production, and decreases collagen production in vitro. We investigated the in vitro effects of minoxidil on behavior such as proliferation and migration of rabbit subconjunctival fibroblasts (SCFs). The ultrastructural effect of the drug on SCFs was also examined. Methods: Proliferation of SCFs and closure of the defect produced in monolayer cultures in the presence or absence of minoxidil was studied. The ultrastructure of SCFs treated with minoxidil was also examined. Results: Minoxidil inhibited SCF proliferation and the closure of the defect produced in monolayer cell sheets. Ultrastructural observations revealed extensive areas of irregularly dilated endoplasmic reticulum in cells treated with minoxidil, indicating the accumulation of protein, probably underhydroxylated collagen precursors, in the cisternae of endoplasmic reticulum. Conclusions: The results indicated that minoxidil attenuated cellular activities of SCFs such as proliferation and migration in vitro. The exact mechanism of the inhibitory effects of minoxidil on these cellular activities is unknown. The findings suggest that the drug might help to prevent bleb scarring after glaucoma filtering surgery. 相似文献
9.
10.
Takeshi Yamashina Ryu Ishihara Noriya Uedo Kengo Nagai Fumi Matsui Natsuko Kawada Takashi Oota Hiromitsu Kanzaki Masao Hanafusa Sachiko Yamamoto Noboru Hanaoka Yoji Takeuchi Koji Higashino Hiroyasu Iishi 《Digestive endoscopy》2012,24(4):220-225
Background and Aim: Limited data are available regarding the use of endoscopic submucosal dissection (ESD) for superficial esophageal cancers ≥50 mm in diameter. The aim of the present study was to investigate the safety and success of ESD for superficial esophageal cancers ≥50 mm. Methods: A total of 39 patients with superficial esophageal squamous cell carcinoma ≥50 mm were treated with ESD at Osaka Medical Center for Cancer and Cardiovascular Diseases between January 2004 and April 2011, and were analyzed in a retrospective study. Results: En bloc resection was achieved in all patients. One mediastinal emphysema without perforation occurred during the procedure. Stricture developed in 11 of 39 patients, requiring a median of five endoscopic balloon dilatation procedures. Thirty‐three clinical epithelial or lamina propria mucosal cancers were treated by ESD with curative intent, of which invasion into the muscularis mucosa or deeper was detected in seven and lymphovascular involvement in three. The en bloc resection rate was 100% with a tumor‐free margin achieved in 92% of lesions. The curative resection and complication rates during ESD were 70% and 2.5%, respectively. Conclusion: ESD achieved a high en bloc resection rate of 92% with a tumor‐free margin. Curative resection rate of ESD in patients with clinical epithelial or lamina propria mucosal cancers was not low at 70%. However, the risk of stricture must be taken into account when considering the use of ESD in lesions ≥50 mm. 相似文献