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Cyanobacterial clock proteins KaiA and KaiC are proposed as positive and negative regulators in the autoregulatory circadian kaiBC expression, respectively. Here, we show that activation of kaiBC expression by kaiA requires KaiC, suggesting a positive feedback control in the cyanobacterial clockwork. We found that robust circadian phosphorylation of KaiC. KaiA was essential for in vivo KaiC phosphorylation and activated in vitro KaiC autophosphorylation. These effects of KaiA were attenuated by the kaiA2 long period mutation. Both the long period phenotype and the abnormal KaiC phosphorylation in this mutant were suppressed by a previously undocumented kaiC mutation. We propose that KaiA-stimulated circadian KaiC phosphorylation is important for circadian timing.  相似文献   
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Solitary metastasis of a malignancy to the spleen is rare. We herein describe a case of splenic metastasis from early gastric cancer. A 76-year-old man underwent an endoscopic mucosal resection (EMR) for early gastric carcinoma in the cardia. Pathologically, the tumor showed invasion into the submucosal layer, and the stump of the surgical specimen appeared to be positive for malignant cells. He thus underwent a proximal gastrectomy with nodal dissection. One year later, serum carcinoembryonic antigen was elevated, and a splenic mass was detected by computed tomography and ultrasonography. Because the tumor increased in size very gradually and no metastatic lesions were detected at the other sites, we performed a splenectomy. The lesion was pathologically diagnosed as metastasis from the previous gastric carcinoma, and the patient remains healthy to date without recurrence, more than 2 years after the splenectomy. When solitary metastasis to the spleen is suspected during the postoperative follow-up of a patient with gastric cancer, a splenectomy is a potentially effective treatment.  相似文献   
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Autophagy is a complex of adaptive cellular response that enhances cancer cell survival in the face of cellular stresses such as chemotherapy. Recently, chloroquine diphosphate (CQ), a widely used antimalarial drug, has been studied as a potential inhibitor of autophagy. Here, we aimed to investigate the role of CQ in potentiating the effect of 5-fluorouracil (5-FU), the chemotherapeutic agent of first choice for the treatment of colorectal cancer, in an animal model of colon cancer. The mouse colon cancer cell line colon26 was used. For the in-vivo study, colon26 cells were injected subcutaneously into BALB/c mice, which were treated with saline as a control, CQ (50 mg/kg/day), 5-FU (30 mg/kg/day), or the combination therapy (CQ plus 5-FU). The tumor volume ratio and body weight were monitored. After the sacrifice, tumor tissue protein extracts and tumor sections were prepared and subjected to immunoblotting for the analysis of autophagy-related and apoptosis-related proteins, and the terminal transferase uridyl end labeling assay. The combination of CQ resulted in the inhibition of 5-FU-induced autophagy and a significant enhancement in the 5-FU-induced inhibition of tumor growth. Furthermore, the combination treatment of CQ and 5-FU resulted in a significant increase in the ratio of apoptotic cells compared with other treatments. The expression levels of the proapoptotic proteins, namely Bad and Bax, were increased by the CQ treatment in the protein extracts from tumors. Our findings suggest that the combination therapy of CQ and 5-FU should be considered as an effective strategy for the treatment of colorectal cancer.  相似文献   
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Chronic spontaneous urticaria, formerly also known as chronic idiopathic urticaria and chronic urticaria (CU), is more common than previously thought. At any time, 0.5-1% of the population suffers from the disease (point prevalence). Although all age groups can be affected, the peak incidence is seen between 20 and 40 years of age. The duration of the disease is generally 1-5 years but is likely to be longer in more severe cases, cases with concurrent angioedema, in combination with physical urticaria or with a positive autologous serum skin test (autoreactivity). Chronic spontaneous urticaria has major detrimental effects on quality of life, with sleep deprivation and psychiatric comorbidity being frequent. It also has a large impact on society in terms of direct and indirect health care costs as well as reduced performance at work and in private life. In the majority of patients, an underlying cause cannot be identified making a causal and/or curative treatment difficult. Nonsedating H?-antihistamines are the mainstay of symptomatic therapy, but treatment with licensed doses relieves symptoms effectively in < 50% of patients. Although guideline-recommended updosing up to fourfold increases symptom control in many patients, a substantial number of patients have only little benefit from H? -antihistamines. Consequently, there is a great need for new therapeutic strategies.  相似文献   
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Background  Disorders in the blood coagulation system are often associated with malignancy. Patients with colorectal cancer (CRC) have been shown to have abnormal data for various coagulation tests. Methods  We retrospectively analyzed the relation between the preoperative plasma fibrinogen level and tumor recurrence in 569 patients with CRC who underwent curative surgical resection and were followed up without adjuvant chemotherapy. Results  The plasma fibrinogen level showed a positive association with tumor recurrence, age, sex, T stage, and TNM classification. When divided with the median value, hyperfibrinogenemia is positively correlated with tumor recurrence, although it lost independence in the multivariate analysis. In the C-reactive protein (CRP)-negative population, hyperfibrinogenemia is independently correlated with tumor recurrence and recurrence-free survival. In contrast, hyperfibrinogenemia has no effect on recurrence in CRP-positive patients. Conclusions   Hyperfibrinogenemia is clinically relevant in tumor recurrence before a systemic inflammatory response and thus can be a useful predictor of recurrence in the preinflammatory stage of CRC.  相似文献   
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