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61.
Takahiro Matsui Akio Iwasa Masafumi Mimura Seiji Taniguchi Takao Sudo Yutaka Uchida Junichi Kikuta Hidetomo Morizono Rie Horii Yuichi Motoyama Eiichi Morii Shinji Ohno Yasujiro Kiyota Masaru Ishii 《Cancer science》2022,113(8):2916
Histopathological diagnosis is the ultimate method of attaining the final diagnosis; however, the observation range is limited to the two‐dimensional plane, and it requires thin slicing of the tissue, which limits diagnostic information. To seek solutions for these problems, we proposed a novel imaging‐based histopathological examination. We used the multiphoton excitation microscopy (MPM) technique to establish a method for visualizing unfixed/unstained human breast tissues. Under near‐infrared ray excitation, fresh human breast tissues emitted fluorescent signals with three major peaks, which enabled visualizing the breast tissue morphology without any fixation or dye staining. Our study using human breast tissue samples from 32 patients indicated that experienced pathologists can estimate normal or cancerous lesions using only these MPM images with a kappa coefficient of 1.0. Moreover, we developed an image classification algorithm with artificial intelligence that enabled us to automatically define cancer cells in small areas with a high sensitivity of ≥0.942. Taken together, label‐free MPM imaging is a promising method for the real‐time automatic diagnosis of breast cancer. 相似文献
62.
Iida T Yasuda M Miyazawa M Fujita M Osamura RY Hirasawa T Muramatsu T Murakami M Saito K Mikami M 《Archives of gynecology and obstetrics》2008,277(6):539-546
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry
in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy.
A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous
13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18).
Results The overall positive ratios were as follows: HIF-1α, 74% of
adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and
100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive
ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly
expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%;
GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical
expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than
in mucinous adenocarcinomas.
Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association
with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared
with mucinous tumors is related to the difference in their histological characteristics. 相似文献
63.
Shizukuishi K Watanabe H Narita H Kanaya S Kobayashi K Yamamoto T Tsukada M Iwanaga T Ikebuchi S Kusama K Tanaka M Namiki N Fuiimura Y Horikoshi A Inoue T Kusakabe K;Working Group of Ministry of Health Labour Welfare for Study about Fitness Management;of Medical Radioactive Waste 《Kaku igaku. The Japanese journal of nuclear medicine》2004,41(2):109-121
We conducted a questionnaire survey about radiation-safety management condition in Japanese nuclear medicine facilities to make materials of proposition for more reasonable management of medical radioactive waste. We distributed a questionnaire to institutions equipped with Nuclear Medicine facilities. Of 1,125 institutions, 642 institutes (52.8%) returned effective answers. The questionnaire covered the following areas: 1) scale of an institution, 2) presence of enforcement of radiotherapy, 3) system of a tank, 4) size and number of each tank, 5) a form of draining-water system, 6) a displacement in a radioactive rays management area, 7) a measurement method of the concentration of medical radioactive waste in draining water system, 8) planned and used quantity of radioisotopes for medical examination and treatment, 9) an average displacement of hospital for one month. In most institutions, a ratio of dose limitation of radioisotope in draining-water system was less than 1.0, defined as an upper limitation in ordinance. In 499 hospitals without facilities of hospitalization for unsealed radioisotope therapy, 473 hospitals reported that sum of ratios of dose limits in a draining-water system was less than 1.0. It was calculated by used dose of radioisotope and monthly displacement from hospital, on the premise that all used radioisotope entered in the general draining-water system. When a drainage including radioactivity from a controlled area join with that from other area before it flows out of a institution, it may be diluted and its radioactive concentration should be less than its upper limitation defined in the rule. Especially, in all institutions with a monthly displacement of more than 25,000 m3, the sum of ratio of the concentration of each radionuclide to the concentration limit dose calculated by used dose of radioisotope, indicated less than 1.0. 相似文献
64.
Shin Kobayashi Naoto Gotohda Toshio Nakagohri Shinichiro Takahashi Masaru Konishi Taira Kinoshita 《World journal of surgery》2009,33(2):312-317
Background Risk factors of surgical site infection (SSI) after hepatectomy under the guideline of Centers for Disease Control and Prevention
(CDC) are not well examined.
Methods Hospital records of consecutive patients who underwent hepatectomy without biliary reconstruction for liver cancers were reviewed
retrospectively. Prophylactic antibiotics were given to patients just before skin incision and every 3 hours during the operations.
Clinicopathological factors were compared between patients who developed SSI and those without it.
Results There were 405 patients identified, and the incidence of SSI was 23 cases (5.8%). In multivariate analysis, intraoperative
bowel injury, blood loss >2000 ml, and age older than 65 years were significant risk factors of SSI after hepatectomy.
Conclusions Prophylactic antibiotics were necessary only during the operation for most patients who underwent hepatectomy without biliary
reconstruction. However, patients with intraoperative bowel injury, blood loss >2000 ml, and age older than 65 years are at
risk to develop SSI and might need additional administration of prophylactic antibiotics after surgery. 相似文献
65.
Takashi Tsukahara Masaru Tamura Hiromichi Yamazaki Hideyuki Kurihara Shigeru Matsuzaki 《Journal of cancer research and clinical oncology》1992,118(3):171-175
Summary The effects of -difluoromethylornithine (DFMO), radiation and the therapy of their combination were investigated in rats bearing G-XII glioma. DFMO treatment as well as radiation therapy prolonged the survival period when compared to the results in non-treated control rats. The combination therapy showed a greater effect on the survival rate than the single therapies, the effect being additive. The concentration of putrescine, spermidine, andN
1-acetylspermidine in tumor tissues was lowered by DFMO, while that of spermine was slightly elevated. Radiation decreased the concentration of all the polyamines, putrescine, spermidine, spermine andN
1-acetylspermidine. The concomitant treatment with DFMO and radiation further decreased the concentrations of putrescine andN
1-acetylspermidine in tumor tissues. The survival period of glioma-bearing rats is inversely correlated with the tissue levels of putrescine plusN
1-acetylspermidine.Abbreviations DFMO
-difluoromethylornithine
- BrdUrd
bromodeoxyuridine 相似文献
66.
Takahiro Hayashi Masaru Miyataka Akio Kimura Mitsugu Taniguchi Atsuhiro Kurooka Hiroshi Yabushita Takashi Kiyoshima Hajime Nakamura Yutaka Hirano Kinji Ishikawa 《Circulation journal》2005,69(4):420-426
BACKGROUND: Many patients with acute myocardial infarction will still die after admission. Recent trends in hospital mortality were analyzed to identify aspects that need improvement. METHODS AND RESULTS: A total of 1,247 patients admitted to Kinki University School of Medicine within 24 h of the onset of infarction were analyzed between 1975 and 2001. The percentage of patients discharged with 100% occlusion decreased gradually from 31.3% during 1975-1982 to 2.1% during 1998-2001, while those with 50% stenosis or less gradually increased from 12.5% to 82.5% during the same period (trends: p < 0.01). The cardiac death rate was 17.1% in 1975-1982, and 7.7% in 1998-2001, showing a significant decrease with time (p < 0.01). This decrease was particularly marked among those admitted within 6 h of the onset of infarction. Death due to cardiac rupture decreased significantly with time (p < 0.001). In contrast, the non-cardiac death rate, amounting to 2.2% on average, did not decline. CONCLUSIONS: Cardiac deaths due to acute myocardial infarction have decreased markedly of late. However, patients must be admitted within 6 h of the onset of infarction to benefit from this improvement. More effort should be made to improve the general care of patients in order to reduce the incidence of non-cardiac death. 相似文献
67.
Eitetsu Tei Hideki Yamamoto Takuya Watanabe Akira Miyazaki Toshio Nakadate Nobumasa Kato Masaru Mimura 《Growth hormone & IGF research》2008,18(1):47-54
OBJECTIVE: Insulin-like growth factor-I (IGF-I) deficiency may be involved in cognitive deficits seen with aging and in neurodegenerative diseases such as Alzheimer's disease (AD). This study was aimed at investigating whether non-responder to donepezil could be predicted using decreased serum levels of IGF-I in AD patients. DESIGN: This study involved 106 elderly subjects: 50 patients with AD and 56 age-matched controls without dementia. In patients with AD, donepezil was given orally 3 mg/day for 4 weeks and 5 mg/day for another 12 weeks. AD patients were divided into responders and non-responders based on the changes in mini-mental state examination (MMSE) scores before and 16 weeks after treatment with donepezil. Serum levels of IGF-I and atherogenic biomarkers were determined. RESULTS: Before treatment with donepezil, there was a significant positive correlation between serum IGF-I levels and the MMSE scores in all subjects. Serum IGF-I levels and the MMSE scores were significantly lower in AD patients than in non-demented controls and were the lowest in non-responders to donepezil. Atherogenic biomarkers (LDL cholesterol, triglycerides, lipoprotein(a), lipid peroxide, apolipoprotein E, and glucose levels) did not differ significantly among these groups. On multiple logistic regression, non-responders to donepezil showed decreased serum IGF-I levels <110 ng/ml and MMSE scores <15 points before treatment. CONCLUSIONS: These findings suggest that decreased levels of serum IGF-I combined with MMSE scores before treatment could predict non-responders to donepezil among AD patients, which may be a simple and practical method for selecting patients expected to show a response to treatment. 相似文献
68.
Aortic valve lesions associated with alkaptonuria tend mostly to be due to aortic valve stenosis, while aortic valve regurgitation is only rarely observed. Herein, a case is reported of severe aortic valve regurgitation and a fibrous strand in a patient with alkaptonuria. A 65-year-old male, with a history of inferior myocardial infarction, presented with symptoms of congestive heart failure. Alkaptonuria was diagnosed based on urine coloration, skin pigmentation and ochronotic arthropathy in the vertebrae and hip. Grade IV aortic valve regurgitation with mild aortic valve stenosis and occlusive disease in the right coronary artery indicated a need for aortic valve replacement and coronary artery bypass grafting. Sclerotic change in the cusps, and shrinkage of the non-coronary cusp, impeded normal coaptation of the aortic valve, and the left-coronary cusp also had a fibrous strand suspending the free margin of the cusp from the aortic wall just above the commissure. The sclerotic change in the cusps, and shrinkage of the non-coronary cusp, appeared to be the causative lesion of aortic valve regurgitation, implying that cardiovascular ochronosis may cause aortic valve regurgitation. 相似文献
69.
Wingfield JC Hahn TP Maney DL Schoech SJ Wada M Morton ML 《General and comparative endocrinology》2003,131(2):143-158
The mountain white-crowned sparrow, Zonotrichia leucophrys oriantha, breeds in subalpine meadows throughout many mountainous regions of western North America. Mathematical analysis of 20 years of egg-laying dates at Tioga Pass, California (3030m elevation) indicated a highly predictable breeding season suggesting that precise environmental cues such as the annual change in day length were important for regulating reproductive function. Additionally, it appeared that there was sufficient yearly variation in the timing of breeding to suggest that other environmental cues may also be important for regulating adjustments in reproductive development and regression. Captive populations of Z. l. oriantha showed strong responses in gonadal development following transfer to longs days (15L 9D) and low temperature (5 degrees C) slowed down photoperiodically induced gonadal growth and subsequent regression, in both males and females. High temperature of 30 degrees C tended to accelerate gonadal development and regression whereas gonadal development was intermediate in a group exposed to 20 degrees C. Prior exposure to these temperature regimes while on short days (9L 15D) had no effect on body mass, fat, or plasma levels of luteinizing hormone (LH) and thyroid hormones. Curiously there was no effect of temperature on photoperiodically induced rises in LH in either sex despite marked effects on gonadal growth. Brood patch development was also enhanced in females exposed to 30 degrees C. Corticosterone levels measured in a subset of plasma samples from this experiment indicated no effect of temperature suggesting that the retarded gonadal development at 5 degrees C was not a result of thermal stress. Although there was a robust effect of photostimulation on thyroid hormone levels in blood of both sexes, temperature treatment had no effect on tri-iodothyronine (T3) concentrations. However, plasma levels of thyroxine (T4) were lower initially at 5 degrees C versus 20 and 30 degrees C treatments. This may be related to the protracted gonadal cycle at 5 degrees C versus the truncated gonadal cycle at 30 degrees C. Molt score, an indication of post-reproductive state and onset of photorefractoriness, was delayed in birds exposed to 5 degrees C. Body mass, and to a lesser extent fat score, tended to be lowest in birds exposed to 5 degrees C compared with those at 20 and 30 degrees C. These results demonstrate that ambient temperature significantly affected photoperiodically induced gonadal development and regression in these birds. The endocrine mechanisms underlying these effects require further study. 相似文献
70.