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991.
Short interfering RNA (siRNA) is a potent activator of the mammalian innate immune system. When considering possible clinical applications of siRNA for humans, the adverse immunostimulatory effects must also be taken into account. Here, we show that atelocollagen-mediated systemic delivery of siRNA without chemical modifications did not cause any immunostimulation in both animals and human peripheral blood mononuclear cells (PBMCs), even if the siRNA harbored an interferon (IFN)-inducible sequence. In contrast, systemic delivery of immunostimulatory RNA (isRNA)-mediated by a cationic lipid (such as Invivofectamine) induced potent type-I IFNs and inflammatory cytokines. Regarding the mechanism by which the isRNA/atelocollagen complex avoided adverse effects on immunostimulation, we revealed that this complex was not incorporated into PBMCs. On the other hand, Invivofectamine delivered isRNA into PBMCs. The use of either atelocollagen or Invivofectamine as a vehicle elicited significant and undistinguishable therapeutic effects in a contact hypersensitivity (CHS) inflammatory model mouse, when we intravenously injected the siRNA targeting monocyte chemoattractant protein-1 as the complex. For the goal of realizing siRNA-based medicines for humans, atelocollagen is an excellent and promising delivery vehicle, and it has the useful advantage of evading detection by the "radar" of innate immunity.  相似文献   
992.
Interleukin-4 receptor α (IL-4Rα) chain is highly expressed on the surface of various human solid tumors. We designed a novel hybrid peptide termed IL-4Rα-lytic peptide that targets the IL-4Rα chain. The IL-4Rα-lytic peptide contains a target moiety to bind to IL-4Rα and a cellular toxic lytic peptide that selectively kills cancer cells. The anticancer activity of the IL-4Rα-lytic peptide was evaluated in vitro and in vivo. It was found that the IL-4Rα-lytic peptide has cytotoxic activity in cancer cell lines expressing IL-4Rα, determined by quantitative real-time PCR. The IC(50) ratios of the lytic peptide to the IL-4Rα-lytic peptide correlated well with the expression levels of IL-4Rα on cancer cells (r = 0.80). In addition, IL-4Rα-lytic peptide administered either intratumoraly or intravenously significantly inhibited tumor growth in xenograft model of human pancreatic cancer (BXPC-3) in mice. These results indicate that the IL-4Rα-lytic peptide generated in this study has a potent and selective anticancer potential against IL-4Rα-positive solid cancers.  相似文献   
993.
The 17 beta-hydroxysteroid dehydrogenases (17 beta HSDs) play an important role in the regulation of intracellular levels of biologically active sex steroid hormones in various human tissues. To date, eight distinctive 17 beta HSD enzymes have been cloned and characterized in humans. Among these isoenzymes, 17 beta HSD type 2 (17 beta HSD2) catalyses the conversion of testosterone into androstenedione and/or oestradiol into oestrone in various tissues, and it has thus been suggested to be involved in the biological inactivation of these sex steroids. The human gastrointestinal tract and liver are considered as the principle sites of inactivation and metabolism of various forms of orally administered sex steroids. We therefore examined 17 beta HSD2 expression and activity in human adult non-pathological gastrointestinal tract in order to clarify further the biological significance of this enzyme. A total of 80 specimens (40 from males and 40 from females) of normal oesophageal, stomach, duodenal, ileal, colonic and rectal tissues were examined for immunohistochemistry. Altogether, 17 tissue specimens were used for enzyme assay, and eight for RNA analysis. 17 beta HSD2 activity was detected in the stomach, duodenum, ileum, colon and rectum. 17 beta HSD2 mRNA was most abundant in the small intestine. 17 beta HSD2 immunoreactivity was localized almost exclusively to the absorptive epithelium, which may be involved in the inactivation of excessive endogenous and exogenous active sex steroids. Results from the present study thus suggest that the human gastrointestinal tract is an important sex steroid metabolizing organ in humans.  相似文献   
994.
The Gyro Pump C1E3 incorporates a doublepivot bearing system as a completely sealless centrifugal pump. The male pivot is made of alumina ceramic, and the female is made of polyethylene. Therefore, the durability of this pump depends upon morphological changes of the female polyethylene pivots, which we examined after clinical usage in the present study. We examined 30 pumps, which were used for cardiopulmonary bypass (CPB), in terms of weight, depth, and surface roughness of the female polyethylene pivots. To determine changes caused by clinical use, we also examined 10 pumps of the same lot numbers with the pumps clinically used and stocked in the factory. There were no significant changes in weight of top and bottom pivots. Also, there was no significant difference in depth and surface roughness of the top pivots. However, there was a significant increase in depth and a decrease in surface roughness of the bottom pivots from clinical use. The results revealed that the bottom pivot, rather than the top pivot, is subject to mechanical deformation by clinical use of the Gyro Pump for CPB. Since morphological changes of the bottom pivot may result from spinning of the impeller at the bottom contact phase, the magnetic coupling distance may need to be increased to obtain more stable spinning of the impeller in a routine CPB.  相似文献   
995.
BACKGROUND/AIMS: Pancreatic cancer is extremely refractory even to aggressive treatments including surgery, resulting in early metastasis and/or local recurrence. We investigated changes in serum tumor marker CA 19-9 levels during preoperative radiotherapy in conjunction with initial treatment failure. METHODOLOGY: Twenty-three patients presenting with localized disease and an increased serum CA 19-9 level, who were slated to undergo pancreatectomy and/or intraoperative radiotherapy following preoperative radiotherapy were reviewed. CA 19-9 response, the ratio of post-radiotherapy level before laparotomy to pre-radiotherapy level, was analyzed in relation to disease-control time and survival. RESULTS: Eleven patients revealed metastasis at restaging or laparotomy; 12 patients (52%) completed aggressive treatments. Initial failure was identified at the liver (52%), peritoneum (52%), or local site (26%) with a median disease-control time of 91 days; 7 patients showed combined failure. All but 1 patient died of cancer with a median survival time of 264 days. CA 19-9 response (range: 0-1185%) did not correlate with disease-control time or survival; 8 progressive-disease patients (> 140% response), however, showed significantly shorter disease-control time than 15 nonprogressive-disease patients (< or = 140% response). CONCLUSIONS: CA 19-9 monitoring is useful in preoperative radiotherapy for identifying patients who will not benefit by succeeding aggressive treatments by predicting early metastasis.  相似文献   
996.
We report a 69‐year‐old man with double cancers in the common bile duct. One cancer was located between the superior and middle parts of the bile duct, while the other cancer was in the inferior part of the bile duct. Pylorus‐preserving pancreatoduodenectomy was performed. There was no communication between the two cancers in either the mucosal layer or the subepithelial layer. On pathological examination, the upper cancer was diagnosed as poorly differentiated adenocarcinoma, while the lower one was found to be moderately differentiated adenocarcinoma. We analyzed loss of heterozygosity (LOH), using microsatellite markers on five chromosomal arms, in both the upper and the lower cancers. Both cancers showed common regions of LOH at 5q, 6q, 9p, 17p, and 18q, whereas the upper cancer showed one additional region of LOH at 8p, thus suggesting progression, due to the acquisition of the additional LOH, in the upper cancer. No LOH was observed in the region between the two cancers. The presence of one additional LOH in the upper cancer suggests that the upper cancer was a metastasis of the lower one.  相似文献   
997.
Background. As of December 1997, more than 170 000 patients in Japan were receiving hemodialysis, 30% to 50% of whom were waiting for a kidney transplant. However, in contrast to the situation in the United States and Europe, kidney transplantation is uncommon, because of the small number of cadaveric kidneys that are donated. As a result, living-related kidney transplantation is performed in as many patients as possible, even in ABO-incompatible cases. Methods. We statistically analyzed the data for 167 ABO-incompatible living donor kidney transplantations that were carried out between January 1989 and December 1997. Results. The overall patient survival rates at 1, 3, 5, and 7 years after transplantation were 90.2%, 90.2%, 88.0%, and 84.8%, respectively, with respective overall graft survival rates of 79.6%, 76.1%, 66.3%, and 56.5%. Conclusions. ABO-incompatible living kidney transplantation is an effective radical treatment for endstage renal disease (ESRD). Received: June 30, 2000 / Accepted: February 22, 2001  相似文献   
998.
A 4-year-old boy with Sotos syndrome had repeated urinary tract infections. Complete right ureteral duplication and bilateral vesicoureteral reflux were, diagnosed, and anti-reflux surgery was performed. This child also had elevated serum creatine kinase levels and atypical absence seizures. The associations of ureteral duplication, continuously elevated serum creatine kinase level, and atypical absence seizure have not been reported previously in Sotos syndrome. Received: March 1, 2001 / Accepted: June 18, 2001  相似文献   
999.
Esophageal metastasis from primary breast cancer is an unusual manifestation. We recently treated a patient with dysphagia, whose breast cancer had been treated in the distant past. A 70-year-old woman had been followed regularly in our outpatient clinic for 14 years after her primary breast cancer treatment, with no apparent tumor recurrence. After 2 years absence, she consulted our clinic with progressive dysphagia. Contrast esophagography and endoscopic examination with ultrasonography revealed a protruding submucosal tumor that was histopathologically diagnosed as esophageal metastasis of breast cancer. Radiation therapy involving a total of 60 Gy in combination with aromatase inhibitor was given. The patient’s dysphagia was greatly relieved, concomitant with marked improvement of the stenotic lesion on imaging. Since treatment for recurrent breast cancer is generally palliative, systemic (chemo- and/or endocrine-) therapy in combination with radiotherapy is the first-line option for esophageal metastasis of breast cancer.  相似文献   
1000.

Purpose  

5-S-Glutathionyl-N-β-alanyl-3,4-dihydroxyphenylalanine (5-S-GAD) is a novel antibacterial substance purified from Sarcophaga peregrina (flesh fly) that has both a radical scavenging activity and antioxidative activity. This is a report of an investigation of the effect of 5-S-GAD (eyedrops) on UVB-induced cataracts in rats.  相似文献   
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