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31.
To elucidate the early events of blood-borne metastasis under actual blood flow, real-time trafficking of RAW117 large cell lymphoma cells, namely parental RAW117-P and liver-metastatic RAW117-H10 cells, was investigated using positron emission tomography (PET). Both types of cells accumulated in the liver immediately after injection via the portal vein, and were eliminated from the liver time-dependently. The elimination rate of RAW117-H10 cells, however, was slower than that of RAW117-P cells, suggesting that RAW117-H10 cells interact more strongly with hepatic sinusoidal endothelium than the parental cells. This result correlated with the metastatic potential of these cells: RAW117-H10 cells metastasized in the liver to a greater extent than RAW117-P cells after injection via this route. To investigate the role of sialylglycoconjugates in the interaction of RAW117-H10 cells with the hepatic endothelium after injection via the portal vein, the trafficking of RAW117-H10 cells was examined after the cells had been treated with sialidase. The elimination rate of RAW117-H10 cells from liver was observed to be greatly accelerated by sialidase treatment. To elucidate what kind of sialylglycoconjugates is related to this phenomenon, we analyzed the distribution of sialyl Lewis A and sialyl Lewis X antigens of both sublines of RAW117 by using flow cytometry. RAW117-H10 cells were found to express a much higher level of sialyl Lewis A than RAW117-P cells, whereas the amount of sialyl Lewis X did not differ significantly. These findings suggest that some sialylglycoconjugates, perhaps sialyl Lewis A in particular, play an important role in the initial interaction of RAW117-H10 cells with the hepatic endothelium, leading to metastasis.  相似文献   
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In a 2-year carcinogenicity study of potassium iodide (KI) in F344/DuCrj rats, squamous cell carcinomas (SCCs) were observed in the salivary glands of 4/40 males and 3/40 females receiving 1000 ppm KI in the drinking water. Ductular proliferation with lobular atrophy was observed at high incidence in the submandibular glands of the high-dose animals, and squamous metaplasia was frequently evident within the proliferative ductules and the larger interlobular ducts. A transition from metaplasia to SCC was apparent. The results suggest that squamous metaplasia in proliferative ductules, occurring secondarily to lobular impairment induced by KI, may develop into SCCs via a non-genotoxic, proliferation-dependent mechanism.  相似文献   
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Gastric cancer (GC) continues to be a significant problem worldwide and is the third leading cause of cancer death. Armamentarium to treat GC whether it is potentially curable or metastatic (incurable) has changed little over the last decades with only two new agents being approved (trastuzumab and ramucirumab). Many relatively healthy patients after second-line therapy have limited and generally ineffective options. The recent The Cancer Genome Atlas analysis has uncovered four genotypes of GC; however, it is not sufficient to change our treatment strategies and more work needs to be done. The popular front-line regimen containing a platinum compound and a fluoropyrimidine is widely used for drug development and has worked well globally. Thus, this combination appears suitable for adding a biologic agent. The search for new classes of cytotoxics has almost stopped, but it is clear that cytotoxic therapy continues to contribute and it is here to stay. Biologic agents that modulate the immune system of the host appear promising along with many other biologics that can potentially inhibit signaling pathways that are often employed by GC cells. We will briefly describe the efforts that have targeted EGFR, mTOR, angiogenesis and MET pathways.  相似文献   
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Objective: To find a risk factor for “uncomplicated” preeclampsia (PE) comparing blood biochemical parameters between women with uncomplicated PE and healthy pregnant women in each trimester of pregnancy. Methods: A retrospective study was performed on 83 cases of uncomplicated PE, selected from 434 patients with PE, disregarding subjects with other complications relevant to hypertension during pregnancy. The study was limited to women with PE occurring in the third trimester, and records of blood biochemical parameters were evaluated. Controls were recruited from 108 healthy volunteers with normal singleton pregnancies. Results: A significant decrease in total protein was observed in the uncomplicated PE group in the second trimester prior to the onset of clinical symptoms. Conclusion: Hypoproteinemia during pregnancy may be a risk factor for this pathophysiology, and the maintenance of sufficient protein in early pregnancy could contribute to prophylaxis for women with uncomplicated PE.  相似文献   
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