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11.
Although there are at least 13 interferon-alpha (IFN-alpha) subtypes in humans, interactions between the subtypes remain unknown. To understand IFN-alpha interactions, we examined the antiproliferative activities and the receptor binding affinities of different combinations of IFN-alpha2 and IFN-alpha8 using six renal cell carcinoma (RCC) cell lines. Although IFN-alpha8 was the more potent subtype, synergistic and antagonistic antiproliferative effects were also observed in certain combinations of IFN-alpha2 and IFN-alpha8. To analyze the interactions between IFN-alpha2 and IFN-alpha8, the receptor-binding kinetics of different combinations of IFN-alpha2 and IFN- alpha8 to the IFN-alpha receptors, IFNAR-1 or IFNAR-2, were measured using a surface plasmon resonance-based biosensor. Unexpectedly, the receptor binding kinetics to IFNAR-2 but not to IFNAR-1 were mutually related to antiproliferative activity and increase in the binding speed (K(a)) for IFNAR-2. Moreover, we observed the increased fluorescence intensity (FI) of biotin-labeled IFN-alpha8 to IFNAR-2 by receptor binding inhibition assay with unlabeled IFN-alpha2 but not the other combinations. These findings indicate that the binding manner of IFN-alpha8 for IFNAR-2 is different from that of IFN-alpha2, suggesting that binding of IFN-alpha8 rather than binding of IFN-alpha2 to IFNAR-2 leads to activation and subsequent antiproliferative activity despite the same antiviral activity in RCC.  相似文献   
12.
BACKGROUND: The RING-H2 finger protein RBX1 (ROC1/HRT1) is a common subunit of SKP1-CDC53/CUL1-F-box (SCF), other cullins and von Hippel-Lindau (VHL) tumour suppressor E3 ubiquitin ligase complexes. RBX1 protein sequences are highly conserved in various species, including yeasts, Drosophila melanogaster, mice and humans. In Saccharomyces cerevisiae, RBX1 is essential for the G1/S transition. RESULTS: Caenorhabditis elegans RBX1 is strongly expressed in early embryos and in the gonad, including meiotic cells. Depletion of RBX1 by RNA-mediated interference (RNAi) caused pronounced defects in the first meiotic division. Several irregular phenotypes were identified in embryos that escaped from meiotic arrest: defects in mitotic chromosomal condensation and segregation, abnormal chromosome bridges, giant nuclei, abnormal cortical protrusion, multinucleate cells and defects in germ cell proliferation. Moreover, histone H3 phosphorylation at Ser10 and Ser28 was significantly reduced in these embryos. The histone H3 phosphorylation defect of embryos was rescued by the additional depletion of protein phosphatase 1 (GLC7alpha/beta) by RNAi. CONCLUSION: These results indicate that the RBX1 protein participates in diverse functions relevant to chromosome metabolism and cell cycle control.  相似文献   
13.
A case of polypoid carcinosarcoma of the esophagus is presented. Histologically the bulk of the tumor consisted of a sarcomatous tissue having large foci of osseous and cartilagenous differentiation and infiltrating deeply the wall, whereas a superficially, invasive squamous cell carcinoma associated with insitu carcinoma was located at the base and luminal surface of the polypoid tumor. Intermingling of the carcinomatous and sarcomatous elements was found only in areas where they appeared to be collided. Ultrastructurally the sarcomatous portion contained cells with fibroblastic features but with no typical epithelial characteristics. Immunoperoxidase staining of the paraffinembedded histologic sections for keratin proteins revealed, however, some positive spindle cells indicative of epithelial nature in the sarcomatous area, but the great majority of the sarcoma cells were devoid of keratin. These combined findings strongly suggest that the sarcomatous component in our case of true carcinosarcoma is derived from mesenchymal transformation (metaplasia) of the squamous carcinoma cells. The findings were discussed in light of the previous pertinent literature. ACTA PATHOL, JPN. 34: 669–678, 1984.  相似文献   
14.
BackgroundAlthough the clinical outcomes of arthroscopic rotator cuff repair (ARCR) have been reported, few studies have focused on diabetic patients. We investigated and compared the clinical results of ARCR in patients with and without diabetes.MethodsThis retrospective study involved 195 consecutive patients who underwent ARCR from 2015 to 2018 in our hospital. Twenty-seven and 168 shoulders were assigned to diabetes and non-diabetes groups, respectively. Diabetic patients with poor control were preoperatively hospitalized for perioperative diabetic control. We evaluated range of motion (ROM), Japanese Orthopaedic Association shoulder (JOA) score, Constant Shoulder Score, and University of California, Los Angeles (UCLA) score preoperatively and at 6 months and 1 year post-ARCR. Rates of rotator cuff retear 1 year post-ARCR and preoperative and postoperative stiff shoulder were also evaluated. We compared the results between groups and analyzed them statistically. A p-value of <0.05 was considered statistically significant.ResultsPreoperative ROM, JOA score, Constant Shoulder Score and UCLA scores showed significant improvement at post-ARCR in both groups (p < 0.05). On comparing the groups, although preoperative JOA score and Constant Shoulder Score were significantly lower in diabetes group than in non-diabetes group (diabetic/non-diabetic group; 60.0/65.3 for JOA score; p = 0.003, 59.7/64.2 for Constant Shoulder Score; p = 0.003), there was no significant difference postoperatively (6 months post-ARCR; 88.0/89.7 for JOA score; p = 0.783, 88.1/88.6 for Constant Shoulder Score; p = 0.597, 1 year post-ARCR; 96.7/95.4 for JOA score; p = 0.238, 96.6/95.4 for Constant Shoulder Score; p = 0.248). Furthermore, preoperative and postoperative stiff shoulder and retear rates were not significantly different between groups (p = 0.152, p = 0.344, p = 0.347, and p = 0.563, respectively).ConclusionDiabetic patients showed comparable clinical results with non-diabetic patients post-ARCR. Perioperative diabetic control may be recommended for preoperatively uncontrolled diabetic patients.  相似文献   
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16.
Clinical and Experimental Nephrology - The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the...  相似文献   
17.
Alopecia is one of the common symptoms after high-dose radiation exposure. In our experiments, neonatal mice that received 7 Gy X-ray exhibited defects in overall hair growth, except for their cheeks. This phenomenon might suggest that some substances were secreted and prevented hair follicle loss in the infant tissues around their cheeks after radiation damage. In this study, we focused on exosome-like vesicles (ELV) secreted from cheek skin tissues and back skin tissues, as control, and examined their radiation protective effects on mouse fibroblast cell lines. We observed that ELV from irradiated cheek skin showed protective effects from radiation. Our results suggest that ELV from radiation-exposed cheek skin tissue is one of the secreted factors that prevent hair follicle loss after high-dose radiation.  相似文献   
18.
The impact of changes in nutritional status during hospitalization on prognosis in patients with heart failure with preserved ejection fraction (HFpEF) remains unknown. We examined the association between changes in the Geriatric Nutritional Risk Index (GNRI) and prognosis during hospitalization in patients with HFpEF stratified by nutritional status on admission. Nutritional status did and did not worsen in 348 and 349 of 697 patients with high GNRI on admission, and in 142 and 143 of 285 patients with low GNRI on admission, respectively. Kaplan–Meier analysis revealed no difference in risk of the composite endpoint, all-cause death, or heart failure admission between patients with high GNRI on admission whose nutritional status did and did not worsen. In contrast, patients with low GNRI on admission whose nutritional status did not worsen had a significantly lower risk of the composite endpoint and all-cause death than those who did. Multivariable analysis revealed that worsening nutritional status was independently associated with a higher risk of the composite endpoint and all-cause mortality in patients with low GNRI on admission. Changes in nutritional status during hospitalization were thus associated with prognosis in patients with malnutrition on admission, but not in patients without malnutrition among those with HFpEF.  相似文献   
19.
Transthyretin (TTR), the precursor protein for amyloidogenic TTR (ATTR) amyloidosis, forms tetramers and escapes glomerular filtration by binding with thyroxine and retinol-binding protein. However, variant TTRs are unstable as tetramers, so monomeric TTR has become the precursor protein of amyloid deposits, via protein misfolding. The aim of the study was to evaluate the utility of urinary TTR in the diagnosis of ATTRv amyloidosis. Urinary samples from healthy volunteers, ATTRv V50M amyloidosis patients, and asymptomatic carriers of the ATTRv V50M gene were analysed using ELISA. To analyse the different forms of TTR secreted to the urine, we performed Western blotting and mass spectrometry. Urinary TTR concentrations were significantly higher in the ATTRv V50M amyloidosis patients than they were in the healthy volunteers and asymptomatic carriers of the gene. Although the TTR concentrations were negligible in the healthy volunteers, they were correlated with disease progression and urinary albumin concentrations in the ATTRv V50M amyloidosis patients. The Western blotting and mass spectrometry revealed the presence of monomeric wild-type and variant TTRs in the urine. Urinary TTR concentrations may become a more sensitive biomarker of ATTRv progression than albumin.  相似文献   
20.
Phospholamban p.Arg14del is reported to cause hereditary cardiomyopathy with malignant ventricular tachycardia (VT) and advanced heart failure. However, the clinical courses of Japanese cardiomyopathy patients with phospholamban p.Arg14del remain uncharacterized. We identified five patients with this variant. All patients were diagnosed with dilated cardiomyopathy (DCM), developed end-stage heart failure and experienced VT requiring implantable cardioverter defibrillator discharge. Four patients survived after implantation of a left ventricular assist device (LVAD), while one patient who refused LVAD implantation died of heart failure. Based on the severe course of the disease, we propose genetic screening for phospholamban p.Arg14del in DCM patients.  相似文献   
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