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BACKGROUND/AIMS: As conditional knockout mice for stat3 are impaired in liver regeneration after partial hepatectomy while those for gp130 have defects in early STAT3 phosphorylation but have normal DNA synthesis, late STAT3 phosphorylation induced independently of gp130 seems to be essential for liver regeneration. Since HGF and EGF can activate STAT3 via gp130-independent MET and EGFR, respectively, we assumed that these factors account for STAT3-dependent liver regeneration. Here, we investigated this hypothesis by introducing suppressor of cytokine signaling (SOCS)-1 and SOCS3, potent negative regulators of STAT3 signaling, selectively in hepatocytes. METHODS: We generated recombinant adenoviruses expressing socs1 and socs3. RESULTS: Hepatocytes infected with socs1-virus lacked STAT3 phosphorylation in response to IL-6 and HGF, while cells infected with socs3-virus lacked the response to all of IL-6, HGF and EGF, indicating that those SOCS proteins differently regulate EGFR signaling. Mice infected with socs3-virus exhibited severe and persistent impairment while those with socs1-virus showed only delayed regeneration, indicating requirement of both MET and EGFR signalings. CONCLUSIONS: These results clearly demonstrated that MET- and EGFR-mediated STAT3 signalings cooperatively contribute to liver regeneration and could provide new insights into tissue homeostasis.  相似文献   
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A recently developed method to quantitate prothrombin in plasma uses the carinactivase-1 (CA-1) method. The present study was designed to establish the reference value by the CA-1 method in the neonatal period and to explore the effect of gestational age, birth weight, concurrent diseases, and vitamin K administration on the prothrombin levels. We enrolled 78 consecutive neonates. The gestational ages ranged from 28 to 41 weeks, and the birth weight ranged from 850 to 3750 g. Twenty-nine infants had concurrent diseases, and the others (n = 49) were healthy. A 300 microL blood sample was drawn into a plastic syringe containing 60 U freeze-dried buffered heparin. Prothrombin levels did not differ between appropriate-for-date (AFD) and light-for-date (LFD) babies (p = 0.090) or between groups with and without concurrent diseases (p = 0.210). In healthy AFD babies, prothrombin levels correlated with gestational age (r = 0.465, p = 0.003) and birth weight (r = 0.458, p = 0.003). In healthy low-birth-weight infants (n = 14) and those with concurrent diseases (n = 17), the changes after vitamin K administration were not significant. The CA-1 method is of clinical use in monitoring coagulation during the early neonatal period.  相似文献   
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Microcystins, which are cyclic heptapeptides produced by some cyanobacterial species from algal blooms, strongly inhibit serine/threonine protein phosphatase and are known as hepatotoxins. Microcystins have many structural variations, yet insufficient information is available on the differences in the cytotoxic potentials among the structural variants. In this study, the cytotoxicities of 16 microcystin variants at concentrations of 0.03–10 μg/mL to primary cultured rat hepatocytes were determined by measuring cellular ATP content, and subsequently determined by their 50% inhibitory concentration (IC50). Differences in the amino acid constituents were associated with differences in cytotoxic potential. [d-Asp3, Z-Dhb7] microcystin-LR exhibited the strongest cytotoxicity at IC50 of 0.053 μg/mL among the microcystin variants tested. Furthermore, [d-Asp3, Z-Dhb7] microcystin-HtyR was also highly cytotoxic. These results suggest that both d-Asp and Z-Dhb residues are important in determining the cytotoxic potential of microcystin variants.  相似文献   
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BACKGROUND: The positron emission tomography (PET) with F18 17beta-estradiol (FES) has good imaging for assessment of estrogen receptor in breast cancer. CASE: We report on a 30-year-old woman who desired to preserve her fertility with well-differentiated endometrial adenocarcinoma. Before hormone treatment was started, FES-PET showed increased uptake of endometrium, magnetic resonance imaging (MRI) showed thickness and F-18 fluorodeoxyglucose (FDG)-PET showed increased uptake. FES-PET after 3 months showed remaining FES uptake, but there were no abnormal findings on MRI and FDG-PET. Hysteroscopy showed remaining adenocarcinoma. After additional treatment, FES-PET showed a therapeutic response, and hysteroscopy showed no abnormal finding. CONCLUSIONS: To our knowledge, this is the first report that FES-PET has the potential to provide more useful information than did FDG-PET about the hormone therapy.  相似文献   
88.
Open in a separate windowOBJECTIVESTo clarify survival outcomes and prognostic factors of patients receiving epidermal growth factor receptor (EGFR) - tyrosine kinase inhibitors (TKIs) as first-line treatment for postoperative recurrence.METHODSA retrospective chart review was performed to identify consecutive patients who received EGFR-TKIs as first-line treatment for postoperative recurrence of non-small-cell lung cancer (NSCLC) harbouring EGFR gene mutations at our institution between August 2002 and October 2020. Therapeutic response, adverse events, progression-free survival (PFS) and overall survival (OS) were investigated. Survival outcomes were assessed using the Kaplan–Meier analysis. The Cox proportional hazards model was used for univariable and multivariable analyses.RESULTSSixty-four patients were included in the study. The objective response and disease control rates were 53% and 92%, respectively. Grade 3 or greater adverse events were noted in 4 (6.3%) patients, including 1 patient (1.6%) of interstitial pneumonia. The median follow-up period was 28.5 months (range 3–202 months). The total number of events was 43 for PFS and 23 for OS, respectively. The median PFS was 18 months, and the median OS was 61 months after EGFR-TKI treatment. In multivariable analysis, osimertinib showed a tendency to prolong PFS [hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.12–1.1; P = 0.071], whereas the micropapillary component was significantly associated with shorter OS (HR 2.1, 95% CI 1.02–6.9; P = 0.045).CONCLUSIONSEGFR-TKIs as first-line treatment appeared to be a reasonable treatment option in selected patients with postoperative recurrent EGFR-mutated NSCLC. Osimertinib and the micropapillary component may be prognostic factors.  相似文献   
89.
Objective We recently reported a novel score for the detection of glomerular filtration rate (GFR) overestimation using a creatinine-based equation. We examined the utility of this score in patients with cardiovascular/renal diseases and diabetes mellitus. Methods We enrolled 1,425 patients (65±15 years old; 37% women) who were admitted to our hospital for the management of cardiovascular and renal diseases and their risk factors. Overestimation of the GFR (OE) was defined as a creatinine-based GFR (eGFRcre) ≥120% of the cystatin C-based estimated GFR. The OE score was calculated as the sum of the scores for the body weight, hemoglobin concentration, and blood urea nitrogen (BUN)/serum creatinine (Scr), totaling 1 point if the body weight was <63.0 kg in men or <42.0 kg in women, 1 point if the hemoglobin concentration was <12.4 g/dL in men or <11.0 g/dL in women, and 1 point if the BUN/Scr was >26.5. Results The proportion of patients with OE was 14.2%. The score predicted OE with a sensitivity of 70.8% and a specificity of 99.6%, and the sensitivity was increased in patients ≥75 years old (88.3%) and decreased in diabetics (58.6%). When patients were divided into subgroups by the total score, the frequencies of OE were 8% (59/754), 14% (72/502), 38% (58/151), and 72% (13/18) in patients with scores of 0, 1, 2, and 3, respectively. Conclusion The OE score is useful for detecting elderly cases of cardiovascular and renal diseases in which eGFRcre overestimates the GFR, although its utility is limited in diabetics.  相似文献   
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