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1.
Bradykinin-stimulated prostacyclin synthesis in porcine aortic endothelial cells was enhanced by pretreatment of the cells with pertussis toxin or islet-activating protein (IAP) for 5 hr or longer. Although ADP-ribosylation of a protein with a molecular weight of 41–42 kD in the cell membranes was completed by 3 hr after the addition of IAP into the incubation medium, there was good correlation between enhancement of bradykinin-induced prostacyclin synthesis and ADP-ribosylation of the IAP substrate over a wide range of IAP concentrations. Furthermore, even if IAP was removed from the incubation medium at 3 hr, bradykinin-induced prostaglandin synthesis at 24 hr was still potentiated. Cycloheximide and actinomycin D enhanced bradykinin-induced prostacyclin synthesis and apparently blocked the effect of IAP. Since this result suggested the involvement of an inhibitor protein(s) of prostacyclin synthesis in the IAP effect, we studied the effect of IAP on the level of lipocortin I which is known to inhibit phospholipase A2. Western and Northern blot analyses revealed that IAP decreased the amounts of protein and mRNA of lipocortin I. These results suggest that the enhancement of bradykinin-induced prostacyclin synthesis by IAP is associated with a decrease in the level of lipocortin I.  相似文献   
2.
Background Fusobacterium nucleatum (F. nucleatum) is a gut microbe implicated in gastrointestinal tumorigenesis. Predicting the chemotherapeutic response is critical to developing personalised therapeutic strategies for oesophageal cancer patients. The present study investigated the relationship between F. nucleatum and chemotherapeutic resistance in oesophageal squamous cell carcinoma (ESCC).Methods We examined the relationship between F. nucleatum and chemotherapy response in 120 ESCC resected specimens and 30 pre-treatment biopsy specimens. In vitro studies using ESCC cell lines and co-culture assays further uncovered the mechanism underlying chemotherapeutic resistance.Results ESCC patients with F. nucleatum infection displayed lesser chemotherapeutic response. The infiltration and subsistence of F. nucleatum in the ESCC cells were observed by transmission electron microscopy and laser scanning confocal microscopy. We also observed that F. nucleatum modulates the endogenous LC3 and ATG7 expression, as well as autophagosome formation to induce chemoresistance against 5-FU, CDDP, and Docetaxel. ATG7 knockdown resulted in reversal of F. nucleatum-induced chemoresistance. In addition, immunohistochemical studies confirmed the correlation between F. nucleatum infection and ATG7 expression in 284 ESCC specimens.Conclusions F. nucleatum confers chemoresistance to ESCC cells by modulating autophagy. These findings suggest that targeting F. nucleatum, during chemotherapy, could result in variable therapeutic outcomes for ESCC patients.Subject terms: Tumour biomarkers, Oesophageal cancer  相似文献   
3.

Background  

This study investigated issues related to initial stability after stem fixation. Finite element models of the AI-Hip cementless stem were constructed for computer simulation.  相似文献   
4.
Dynamic magnetic resonance imaging (dynamic MRI) was used to examine the synovial membrane in the knee joints of 15 patients with rheumatoid arthritis (RA) in order to investigate the relationship between pathological and MRI findings. Signal intensities in the regions of interest (ROI), identified as the synovial membrane of the suprapatellar pouch, were measured on MR images. Signal intensities at various times after the injection of contrast medium Gd–diethylenetriaminopentoacetic acid (Gd–DTPA) were normalized relative to the signal intensity at 80s, and designated as the normalized signal intensity (NSI). Pathological findings were quantified, and the types of inflamed synovial membrane were classified as either acute or chronic. A significant difference in NSI was observed between acute and chronic types (P 0.05). Dynamic MRI was capable of classifying acute and chronic RA by measuring NSI 20s after contrast medium injection. Dynamic MRI was therefore shown to be useful for assessing regional synovial inflammation.  相似文献   
5.
Radiofrequency ablation (RFA) is increasingly being used for the treatment of intrathoracic malignancies. Although RFA has been found to be promising in the treatment of lung metastases from some types of neoplasms, little is known concerning its clinical significance in the treatment of pulmonary metastasis from esophageal squamous cell carcinoma (ESCC). This retrospective study evaluated the feasibility, safety, and effectiveness of computed tomography‐guided RFA for pulmonary metastasis from ESCC. A series of 10 ESCC patients with 17 pulmonary tumors were included. Correct placement of the ablation device into the target tumor proved to be feasible in all tumors (100%). The mean visual analog scale score, with values that ranged from 0 (no pain) to 10 (worst pain possible), was 1. This suggested that this procedure was well tolerated. No procedure‐related deaths occurred. A pneumothorax needing drainage was a major complication in two patients. Local control of ablated tumor lasting for at least 1 year was achieved in 10 (83%) of 12 assessable tumors. Although locoregional recurrences developed in two tumors, these lesions could be recontrolled by repeat treatment with RFA. Three patients died of recurrent disease. The predicted 1‐ and 2‐year overall survival rates after lung RFA were 77.8% and 62.2%, respectively. Percutaneous computed tomography‐guided RFA yielded relatively high levels of local control in patients with pulmonary metastases from ESCC and was associated with an acceptable level of complications. It was concluded that a prospective study will be necessary to evaluate the effectiveness of a combination of systemic therapy and RFA for ESCC lung metastases.  相似文献   
6.
Cognitive impairment has long been recognized as a complication of chronic kidney disease. However, there is little information available regarding regional cerebral blood flow (rCBF) in patients with peritoneal dialysis (PD). Therefore, we evaluated rCBF using brain single photon emission computed tomography (SPECT). We conducted a cross‐sectional study in our hospital. Eighteen consecutive PD patients who could visit the hospital by themselves without any history of stroke were examined by Technetium‐99 m‐labeled ethylcrysteinate dimer brain SPECT. An easy Z‐score imaging system (eZIS) was used to compare rCBF in PD patients with those in age‐matched healthy controls. We also evaluated cognitive dysfunction with the mini‐mental state examination (MMSE) questionnaire. Only one patient showed an MMSE score of 18 points, and the remaining 14 patients were considered as normal (MMSE ≥ 27), and three patients were considered to have mild cognitive impairment (24 ≤ MMSE ≤ 26). In all patients, rCBF in the posterior cingulated gyri, precunei, and parietal cortices was significantly decreased. The ratio of the reduction of rCBF in each region relative to that of rCBF across the whole brain correlated positively with the PD duration (r = 0.559; P < 0.05). The serum β2‐microglobulin level was significantly higher in patients who had a higher ratio of rCBF reduction compared with those with lower ratios. In conclusion, all PD patients in the present study had decreased rCBF irrespective of MMSE scores.  相似文献   
7.

Background

Epidermal growth factor receptor (EGFR) signaling is one of the most promising targets for molecular-targeted therapies in esophageal squamous cell carcinoma (ESCC). Thus, the molecular diagnosis of KRAS and BRAF mutations is clinically important in therapeutic decision making. However, the frequency of KRAS and BRAF mutations in ESCCs remains inconclusive because of the limited sample sizes of previous studies (all N ≤ 80). Pyrosequencing is a nonelectrophoretic nucleotide extension sequencing technology that can be used for mutation testing.

Methods

The frequency of KRAS and BRAF mutations was examined using a nonbiased database of 203 resected ESCCs and a high-throughput pyrosequencing assay.

Results

The validity of the KRAS pyrosequencing method was initially demonstrated by detection of all 4 types of KRAS mutations [c.35G>T (codon 12 GGT>GTT), c.35G>A (codon 12 GGT>GAT), c.34G>T (codon 12 GGT>TGT), c.38G>A mutation (codon 13 GGC>GAC)], which had been previously diagnosed using Scorpion-ARMS technology, in 9 colon cancer tissues (9 of 9; 100 %). Similar results were demonstrated for BRAF mutational status in 3 colon cancer cell lines (HCT116, Colo201, and HT29), which were validated by Sanger dideoxy sequencing. Subsequently, the KRAS mutation was found to be extremely rare (1 of 203; 0.5 %), and the BRAF mutation was absent (0 of 203; 0 %), in the dataset of 203 ESCCs.

Conclusions

These results suggest that KRAS and BRAF mutations play a limited role in the development of ESCC and that mutation analysis is not useful as a screening test for sensitivity to anti-EGFR therapy in ESCC.
  相似文献   
8.
9.

Background

Although a survival benefit of neoadjuvant treatment for patients with esophageal cancer has been highlighted, the influence of neoadjuvant treatment on the nutritional status of patients with esophageal cancer is not well understood.

Methods

Changes in body composition parameters were assessed in 30 patients who underwent neoadjuvant chemotherapy (NAC) comprising docetaxel, cisplatin, and 5-fluorouracil followed by esophagectomy from August 2009 to April 2013. Body composition was evaluated before and after NAC using multifrequency bioelectrical impedance analysis (InBody 720; Biospace, Tokyo, Japan). Postoperative complications were graded according to the Clavien-Dindo classification.

Results

Twenty-three postoperative events occurred in 16 patients. A decrease in body protein was observed in 13 patients (43.3 %), while skeletal muscle (SM), body cell mass (BCM), and fat-free mass (FFM) declined in 11 patients (36.7 %) during NAC. Changes in these four parameters during chemotherapy significantly differed between patients with postoperative complications and those without: protein, ?1.6 ± 0.9 versus +4.4 ± 2.1 kg (P = 0.01); SM, ?1.3 ± 1.1 versus +4.7 ± 2.4 kg (P = 0.02); BCM, ?2.4 ± 1.6 versus +3.8 ± 2.2 kg (P = 0.03); and FFM, ?1.4 ± 1.4 versus +4.3 ± 2.3 kg (P = 0.04).

Conclusions

Changes in body composition parameters are possible predictive markers of postoperative complications after esophagectomy after NAC. Further analysis is needed to clarify whether nutritional intervention improves such parameters and thus contributes to reduced postoperative morbidity.  相似文献   
10.
BACKGROUND AND AIM: In order to evaluate loss of the p53 gene more precisely, we performed dual-color fluorescence in situ hybridization (dual-color FISH) for chromosome 17 and p53 gene together with DNA polymorphism analysis of the p53 gene in hepatocellular carcinoma (HCC). METHODS: Dual-color FISH using probes specific for the centromere of chromosome 17 and the p53 gene was performed for 41 HCC and DNA polymorphism analysis was also performed for them. RESULTS: Of the 34 HCC tested by dual-color FISH, 20 had loss of at least one p53 gene (58.8%). In contrast, of the 32 HCC tested by DNA polymorphism analysis, 23 gave informative results, among which only eight had loss of heterozygosity (LOH) of the p53 gene (34.8%). Notably, among 14 cases positive for loss of the p53 gene by dual-color FISH, seven cases were negative for LOH of the p53 gene. Moreover, dual-color FISH revealed that the percentage of cells that lost at least one p53 gene increased as the HCC became less differentiated (P < 0.01), whereas LOH did not reveal any such correlation. CONCLUSIONS: These data suggest that loss of the p53 gene was present in a considerable number of HCC, and diversity of the p53 gene aberration increases with progression of HCC. Dual-color FISH is an effective method for detection of p53 gene aberration, and it can provide new insight into oncogenesis in HCC.  相似文献   
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