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101.
AIMS: A novel blood purification material that we previously reported as a superantigen- and cytokine-adsorbing device (SCAD) was evaluated for its ability to adsorb unbound, unconjugated bilirubin (UUBil) in vitro and in vivo. METHODS: In albumin-containing buffer, UUBil was dissolved and circulated through the SCAD column. Also, bilirubin was infused into low-body weight newborn piglets and hemoperfused for 3 h over SCAD columns. RESULTS: In albumin-containing buffer, concentration of bilirubin decreased from 34 to 0.6 mg/dL within 5 h and the SCAD fiber turned brown, indicating that bilirubin was adsorbed onto the surface of the adsorbent and was not degraded during the circulation. Using the hyperbilirubinemia swine, clearances of total bilirubin (TBil), direct bilirubin (DBil), and indirect bilirubin (IdBil) were significantly higher (P<0.01) in the SCAD group compared with the control group. The clearances of TBil, DBil, and IdBil at 3 h after the initiation of the bilirubin infusion were 0.47, 0.53, and 0.45 mL/min, respectively, at a blood flow rate of 2.5 mL/min, and this result indicates that almost 20% of bilirubins were adsorbed to the SCAD column in a single passage. CONCLUSION: These results provide initial evidence that SCAD treatment is effective in the removal of UUBil and can be performed safely in newborn animals.  相似文献   
102.
Recently, fasting has been spotlighted from a healthcare perspective. However, the de-tailed biological mechanisms and significance by which the effects of fasting confer health benefits are not yet clear. Due to certain advantages of the zebrafish as a vertebrate model, it is widely utilized in biological studies. However, the biological responses to nutrient metabolism within zebrafish skeletal muscles have not yet been amply reported. Therefore, we aimed to reveal a gene expression profile in zebrafish skeletal muscles in response to fasting-refeeding. Accordingly, mRNA-sequencing and bioinformatics analysis were performed to examine comprehensive gene expression changes in skeletal muscle tissues during fasting-refeeding. Our results produced a novel set of nutrition-related genes under a fasting-refeeding protocol. Moreover, we found that five genes were dramatically upregulated in each fasting (for 24 h) and refeeding (after 3 h), exhibiting a rapid response to the provided conditional changes. The assessment of the gene length revealed that the gene set whose expression was elevated only after 3 h of refeeding had a shorter length, suggesting that nutrition-related gene function is associated with gene length. Taken together, our results from the bioinformatics analyses provide new insights into biological mechanisms induced by fasting-refeeding conditions within zebrafish skeletal muscle.  相似文献   
103.
A tyrosine kinase adaptor protein containing pleckstrin homology and SH2 domains (APS) is rapidly and strongly tyrosine phosphorylated by insulin receptor kinase upon insulin stimulation. The function of APS in insulin signaling has heretofore remained unknown. APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. Plasma insulin levels during fasting and in the intraperitoneal glucose tolerance test were lower in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin. However, overexpression of wild-type or dominant-negative APS in 3T3L1 adipocytes did not affect insulin receptor numbers, phosphorylations of insulin receptor, insulin receptor substrate-1, or Akt and mitogen-activated protein kinase. The glucose uptake and GLUT4 translocation were not affected by insulin stimulation in these cells. Nevertheless, the insulin-stimulated glucose transport in isolated adipocytes of APS(-/-) mice was increased over that of APS(+/+) mice. APS(-/-) mice also showed increased serum levels of leptin and adiponectin, which might explain the increased insulin sensitivity of adipocytes.  相似文献   
104.
The underlying purpose of this commentary and position paper is to achieve evidence-based recommendations on prevention of work-related musculoskeletal disorders (MSDs). Such prevention can take different forms (primary, secondary and tertiary), occur at different levels (i.e. in a clinical setting, at the workplace, at national level) and involve several types of activities. Members of the Scientific Committee (SC) on MSDs of the International Commission on Occupational Health (ICOH) and other interested scientists and members of the public recently discussed the scientific and clinical future of prevention of (work-related) MSDs during five round-table sessions at two ICOH conferences (in Cape Town, South Africa, in 2009, and in Angers, France, in 2010). Approximately 50 researchers participated in each of the sessions. More specifically, the sessions aimed to discuss new developments since 1996 in measures and classification systems used both in research and in practice, and agree on future needs in the field. The discussion focused on three questions: At what degree of severity does musculoskeletal ill health, and do health problems related to MSDs, in an individual worker or in a group of workers justify preventive action in occupational health? What reliable and valid instruments do we have in research to distinguish ??normal musculoskeletal symptoms?? from ??serious musculoskeletal symptoms?? in workers? What measures or classification system of musculoskeletal health will we need in the near future to address musculoskeletal health and related work ability? Four new, agreed-upon statements were extrapolated from the discussions: 1. Musculoskeletal discomfort that is at risk of worsening with work activities, and that affects work ability or quality of life, needs to be identified. 2. We need to know our options of actions before identifying workers at risk (providing evidence-based medicine and applying the principle of best practice). 3. Classification systems and measures must include aspects such as the severity, frequency, and intensity of pain, as well as measures of impairment of functioning, which can help in prevention, treatment and prognosis. 4. We need to be aware of economic and/or socio-cultural consequences of classification systems and measures.  相似文献   
105.
BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in a wide variety of tumor cells, while it has no toxicity for the majority of normal cells.Therefore, TRAIL may be a suitable agent for anticancer therapy. We previously reported that a number of pancreatic cancer cell lines show resistance to TRAIL-induced apoptosis via overexpression of XIAP and FLIP. The present study was conducted to further examine TRAIL-based therapeutic strategies by aiming to restore functional apoptotic pathways in resistant pancreatic cancer cells. METHODS: In various pancreatic cancer cell lines, TRAIL-induced apoptosis was evaluated in the presence or absence of an XIAP-inhibitor (Smac peptide). Second, TRAIL-induced apoptosis was evaluated in TRAIL-resistant AsPC-1 cells with or without FLIP antisense. Third, the combined effect of Smac peptide and FLIP antisense was tested, and the activation of apoptosis-related caspases and poly (ADP-ribose) polymerase was evaluated. Finally, TRAIL-induced apoptosis was evaluated in the presence or absence of FLIP antisense and an XIAP inhibitor (embelin). RESULTS: Smac peptide enhanced TRAIL-induced apoptosis in a dose-dependent manner for several pancreatic cancer cell lines, but showed no effect on TRAIL-resistant AsPC-1 cells. Smac peptide alone had no influence on cell viability. TRAIL-induced apoptosis was restored in TRAIL-resistant AsPC-1 cells by exposure to FLIP antisense, which suppressed the expression of FLIP. The effect of TRAIL was augmented by the combination of FLIP antisense and Smac peptide. Similarly, TRAIL-induced apoptosis was restored by the combination of FLIP antisense and embelin. Activation of apoptotic caspases and cleavage of poly (ADP-ribose) polymerase was observed after sensitization of TRAIL-resistant pancreatic cancer cells. CONCLUSIONS: Pancreatic cancer cells gain resistance to TRAIL-induced apoptosis via expression of the antiapoptotic proteins XIAP and FLIP. Smac peptide and FLIP antisense could restore the apoptotic effect of TRAIL. An XIAP inhibitor, embelin, enhanced the effect of TRAIL in the presence of FLIP antisense. These findings may provide useful information for the development of TRAIL-based therapeutic strategies by restoring functional apoptotic pathways in resistant pancreatic cancer cells. In addition, a low molecular weight XIAP inhibitor like embelin could be a lead compound for the development of effective XIAP inhibitors.  相似文献   
106.
107.
Chromosomal and microsatellite instability in sporadic gastric cancer   总被引:5,自引:0,他引:5  
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers.  相似文献   
108.
Prostaglandins and thromboxanes are important modulators of airway physiology. The synthesis of these mediators depends on two isoforms of cyclooxygenase (COX), constitutive COX-1 and inducible COX-2. COX-2 expression has been observed in various inflammatory diseases, but not all aspects of the expression and the role of COX-2 in conditions of allergic inflammation such as asthma are clear. In the present study, we examined the 72-h kinetics of the expression of COX-isoform mRNA in ovalbumin-sensitized and -challenged guinea-pig lungs. The sensitized animals showed a robust and transient induction of COX-2 mRNA expression within 1 h after ovalbumin challenge, whereas their COX-1 mRNA levels remained unchanged. Upregulation of the level and activity of COX-2 protein followed the induction of COX-2 mRNA. Lung slices harvested from ovalbumin-challenged animals released more prostaglandin D(2) and prostaglandin E(2) spontaneously or in response to A23187 (10 microM) ex vivo than did those from unchallenged animals. This response was significantly blocked by the COX-2 selective inhibitors, NS-398 and JTE-522. In vivo administration of NS-398 significantly inhibited the accumulation of eosinophils and neutrophils in the lungs. In conclusion, de novo COX-2 expression during allergic inflammation modifies prostanoid synthesis in the lung and airway pathophysiology.  相似文献   
109.

Purpose

Oral mucositis (OM) is one of the most uncomfortable adverse events experienced by cancer patients undergoing chemotherapy. Previous reports have revealed that the oral administration of an elemental diet (ED) may prevent OM. However, the incidence of OM has not been accurately determined by specialized diagnostic methods and the effects of an ED on OM remain unclear. We investigated the dose that could feasibly be administered and its effects with regard to the suppression of OM in esophageal cancer patients undergoing chemotherapy.

Methods

We performed a prospective multi-center feasibility study of the administration of an ED (160 g/day) with 2 cycles of docetaxel/cisplatin/5-FU (DCF) chemotherapy. We assessed compliance to the ED for 49 days and the incidence of OM according to the amount of the ED that was orally administered. The incidence of OM was graded by a dental specialist who was experienced in dental oncology using a central OM review system.

Results

Fourteen of 20 patients (70%) were able to complete the orally administered ED (160 g/day) during the course of chemotherapy. Three patients (15%) could not take the ED orally for 9, 14, and 21 days, respectively, while 1 patient (5%) took the ED orally at an average dose of 80 g/day for 35 days. The remaining 2 patients (10%) could not take the 80 g/day dose for 11 and 12 days, respectively. The incidence of grade?≥?2 OM in the ED completion group (15.4%, 2 of 13 patients) was significantly lower than that in the non-completion group (66.7%, 4 of 6 patients) (p?=?0.046).

Conclusions

An ED might be a one of the test treatment to reduce the incidence of OM in esophageal cancer patients treated with DCF and should be evaluated in further randomized study.

Clinical trial

The date of submission: Dec 08th, 2017.
  相似文献   
110.
BACKGROUND/AIMS: Serum concentrations of the 7S fragment of type IV collagen (7S collagen), amino-terminal propeptide of type III procollagen (PIIIP), and hyaluronic acid (HA) have been reported to serve as serologic markers of liver fibrosis in hepatitis and cirrhosis. We investigated whether these fibrosis markers reliably reflect histologic changes in the livers of patients with hepatocellular carcinoma. METHODOLOGY: Subjects included 165 patients undergoing liver resection for hepatocellular carcinoma. Most were seropositive for chronic hepatitis B or C. Histopathologic changes in liver tissue resected with the tumor were scored according to Knodell's histologic activity index. Serum was sampled for assays shortly before surgery. RESULTS: Significant correlations were found between hepatitis activity score and 7S collagen, PIIIP, and HA. Concentrations of 7S collagen differed significantly between activity grades, but differences were not significant for PIIIP or HA. Significant correlations were found between fibrosis staging score and all these three markers. When patients were divided according to activity grade, 7S collagen showed stronger correlation with fibrosis staging score than did PIIIP or HA. CONCLUSIONS: The 7S collagen fragment correlated more strongly than PIIIP or HA with stage and activity grade in patients with hepatocellular carcinoma. However, overlapping of results between histologically defined groups appeared to limit clinical diagnostic usefulness of all markers in individual patients.  相似文献   
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