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31.
Tatsuo Yamazaki Shigeki Tomita Kazuhito Ichikawa Yuko Ono Fujiyuki Inaba Ichio Fukasawa Yasuo Imai Johji Imura Hirokazu Fukui Takahiro Fujimori Noriyuki Inaba 《Pathobiology》2006,73(4):176-182
OBJECTIVES: We investigated the relationship between P16-immunostaining patterns and clinicopathological factors in early uterine cervix cancers and assessed whether P16-immunostaining patterns predict the prognosis of the patients with early uterine cervix cancers. METHODS: Twenty-nine early squamous cell carcinoma (SCC) specimens of the uterus were examined using immunohistochemistry for P16 expression. The P16-immunostaining pattern was classified into two groups: the homogeneous type and the heterogeneous type. P16-immunostaining patterns were evaluated in different parts of the carcinoma in situ (CIS): the center of the tumor and the front interface of the infiltrating tumor. RESULTS: All specimens were of the homogeneous type in CIS. The P16-immunostaining pattern was significantly of the heterogeneous type in the front interface of the infiltrating tumor with lymphatic invasion, vascular invasion, lymph node metastasis, and recurrence. Regarding the P16-immunostaining patterns in the front interface of the infiltrating tumor, the patients with the heterogeneous type showed a significantly worse prognosis than the patients with the homogeneous type. CONCLUSIONS: The prognosis of patients with early uterine cervical SCC may be predicted by evaluating the P16-immunostaining pattern in the front interface of the infiltrating tumor. 相似文献
32.
Melanin pigmentation in mammalian skin and its hormonal regulation 总被引:37,自引:0,他引:37
Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social communication, and protection against harmful effects of solar radiation. Melanogenesis is under complex regulatory control by multiple agents interacting via pathways activated by receptor-dependent and -independent mechanisms, in hormonal, auto-, para-, or intracrine fashion. Because of the multidirectional nature and heterogeneous character of the melanogenesis modifying agents, its controlling factors are not organized into simple linear sequences, but they interphase instead in a multidimensional network, with extensive functional overlapping with connections arranged both in series and in parallel. The most important positive regulator of melanogenesis is the MC1 receptor with its ligands melanocortins and ACTH, whereas among the negative regulators agouti protein stands out, determining intensity of melanogenesis and also the type of melanin synthesized. Within the context of the skin as a stress organ, melanogenic activity serves as a unique molecular sensor and transducer of noxious signals and as regulator of local homeostasis. In keeping with these multiple roles, melanogenesis is controlled by a highly structured system, active since early embryogenesis and capable of superselective functional regulation that may reach down to the cellular level represented by single melanocytes. Indeed, the significance of melanogenesis extends beyond the mere assignment of a color trait. 相似文献
33.
Mice lacking smooth muscle calponin display increased bone formation that is associated with enhancement of bone morphogenetic protein responses 总被引:5,自引:0,他引:5
34.
Non-essential amino acid L-serine functions as a highly potent, glia-derived neurotrophic factor, because it is a precursor for syntheses of proteins, other amino acids, membrane lipids, and nucleotides, and also because its biosynthetic enzyme 3-phosphoglycerate dehydrogenase (3PGDH) is preferentially expressed in particular glial cells within the brain. Here we pursued 3PGDH expression in peripheral nerves and its change after crush injury. In the pathway of rat sciatic nerves, 3PGDH was selectively expressed in non-neuronal elements: Schwann sheaths and endoneurial fibroblasts in sciatic nerves, satellite cells in dorsal root ganglia, and astrocytes and oligodendrocytes in the spinal ventral horn. In contrast, 3PGDH was immunonegative in axons, somata of spinal motoneurons and ganglion cells, and endoneurial macrophages. One week after crush injury, 3PGDH was upregulated in the distal segment of injured nerves, where 3PGDH was intensified in activated Schwann cells and fibroblasts. 3PGDH was still negative in activated macrophages, which were instead associated or surrounded by activated Schwann cells with intensified 3PGDH. These results suggest that in the peripheral nervous system, these non-neuronal cells synthesize and may supply L-serine to satisfy metabolic demands for maintenance and regeneration of peripheral nerves and for proliferation and activation of macrophages upon nerve injury. 相似文献
35.
Hiroyuki Orita Manabu Fukasawa Shigeki Hirooka Takasi Minowa Hideaki Uchino Masahiko Washio 《Surgery today》1993,23(4):344-349
We evaluated the preventive effect of postischemic reperfusion injury by Nicorandil-Mg cardioplegia given just prior to reperfusion as terminal cardioplegia. Twenty seven dogs were placed on cardiopulmonary bypass and the aorta was cross-clamped for 90 min under hypothermic (17–19°C) cardioplegic arrest. The canine hearts were divided into three groups: in group A (n=10) the hearts were reperfused without any treatment; in group B (n=9) the hearts received coronary perfusion with Nicorandil-Mg solution (Nic, 8 mg/l; Mg, 20 mEq/l; glucose, 50 g/l) for 2 min just prior to reperfusion; and in group C (n=8) the hearts received coronary perfusion with Nicorandil-Mg free solution (glucose, 50g/l). During and after ischemia, the myocardial tissue PCO2 (t-PCO2) was continuously monitored by an ion-sensitive field effective transistor (ISFET) sensor. In addition, the myocardial tissue blood flow (TBF), oxygen consumption, and lactate flux were then calculated at 5, 10, 20, and 40 min of reperfusion. In the initial reperfusion period, Group B showed an improved TBF compared to group A and C (at 5 min, group B was 42.7±11.9; group A was 29.4±11.2, P<0.025; and group C was 33.9±9.2% of the preischemic control level, P<0.05). T-PCO2 in group B was significantly decreased at 5 min of reperfusion (group B, 127.5±22.5 42.5±9.7; group A, 117.5±23.0 85.2±17.4, P<0.001; group C, 122.3 mmHg 68.2±18.7 mmHg, P<0.01), and group B had a better metabolic recovery. These results suggest that terminal Nicorandil-Mg cardioplegia might reduce the rate of postischemic reperfusion injury. 相似文献
36.
37.
Takafumi Ichida Masashi Kato Akihito Hayakawa Shinichi Ito Shigeki Mori Tomomi Sato Souichi Sugitani Hiroshi Sato Masashi Watanabe Hitoshi Asakura 《Cancer chemotherapy and pharmacology》1994,33(Z1):S74-S78
Prior injection of an anticancer agent and Lipiodol mixture is a key point for the treatment of hepatocellular carcinoma (HCC). We therefore prepared a new, improved emulsion of Lipiodol containing a high dose ofcis-diamminedichloroplatinum (CDDP) and epirubicin by replacing the ionic contrast medium (Urografin 67) with a nonionic contrast medium (Iopamidol; Iopamiron 300) and adding phosphatidyl choline. This CDDP-epirubicin-Lipiodol emulsion (CELE) was examined pharmacologically and chemically with the following results. The size of these particles is less than 10 m (diameter) for up to 24 h; the release of 28%–34% of the CDDP and 80%–90% of the epirubicin was estimated in the dissolution test, and 85% of the CDDP and 35% of the epirubicin was retained in the organs in the moment calculation. CELE was injected into 58 HCC patients via a celiac angiographic catheter. In 36 of these patients, the CELE injection was followed by transcatheter arterial embolization (TAE) therapy. Following the administration of CELE as one-shot injection therapy for stage IV HCC, the 1-year survival rate was 59% and the 2-year survival rate was 27%. Moreover, in patients (stage II, 12; stage III, 8; stage IV, 16) who received CELE and subsequently underwent TAE therapy, the 1-year survival rate was 90% and the 2-year survival rate was 67%. The nonionic contrast medium with Lipiodol forms finer emulsified particles, and these particles are more capable of penetrating into the tumor. In addition, the greater pharmacological stability of these particles provides a slow-release effect and prolonged stability of their shape. Finally, theoretically, the use of two major anticancer agents such as CDDP and epirubicin showed a greater clinical effect in the treatment of HCC than either our earlier suspension or a single anticancer agent.Work presented at the Third International Symposium on Treatment of Liver Cancer, Seoul, Korea, 12–13 February 1993 相似文献
38.
Motonobu Kameyama Kiichi Ishiwata Yuji Tsurumi Jun Itoh Kiyotaka Sato Ryuichi Katakura Takashi Yoshimoto Jun Hatazawa Masatoshi Ito Tatsuo Ido 《Journal of neuro-oncology》1995,23(1):53-61
Summary Positron emission tomography was used to investigate the metabolism of nucleic acids by18F-fluoro-2-deoxyuridine (18F-FUdR) in 22 patients with gliomas. Sixteen cases of high grade glioma clearly demonstrated a region of high activity with a differential absorption rate (DAR) of 0.64 ± 0.34. Six cases of low grade glioma failed to reveal a positive image of the tumor and the DAR in tumor was 0.21 ± 0.042 (p < 0.01). This PET-18F-FUdR study succeeded in differentiating high and low grade gliomas from the view point of nucleic acid metabolism. 相似文献
39.
Total Esophagectomy versus Proximal Esophagectomy for Esophageal Cancer at the Cervicothoracic Junction 总被引:1,自引:0,他引:1
Fujita H Kakegawa T Yamana H Sueyoshi S Hikita S Mine T Tanaka Y Ishikawa H Shirouzu K Mori K Inoue Y Tanabe HY Kiyokawa K Tai Y Inutsuka H 《World journal of surgery》1999,23(5):486-491
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic
junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two
groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy
with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy
resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy
compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy
(total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different
between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper
mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or
without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients. 相似文献
40.
Shigeki Wakiyama Katsuhiko Yanaga Yuji Soejima Takashi Nishizaki Tomoharu Yoshizumi Keizo Sugimachi 《Transplant international》1996,9(4):359-363
We studied the significance of N-acetyl--glucosaminidase (-NAG) and type III procollagen peptide (P-III-P) in the effluent of rodent hepatic grafts. After total hepatectomy, the livers were preserved in chilled, lactated Ringer's solution and then divided into five groups (n=10 each): group 1, 4 h preservation only; group 2, 4 h preservation and rewarming; group 3, 6 h preservation only; group 4, 6 h preservation and rewarming; and group 5, minimal preservation only. The -NAG of groups 2 and 4 was significantly higher than that of groups 1 and 3 (0.98±0.5 U/l vs 0.21±0.12 U/l; P<0.01 and 1.76±0.67 U/l vs 0.38±0.25 U/l, respectively; P<0.01), while that of group 4 was significantly higher than that of group 2 (1.76±0.67 U/l vs 0.98±0.50 U/l; P<0.05). The P-III-P of group 4 was significantly higher than that of group 2 (0.133±0.008 U/ml vs 0.110±0.015 U/ml; P<0.01). We conclude that -NAG is a novel parameter of parenchymal and nonparenchymal cells, while P-III-P reflects the integrity of the hepatic sinusoidal extracellular matrix. 相似文献