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81.
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy. A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous 13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18). Results The overall positive ratios were as follows: HIF-1α, 74% of adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and 100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%; GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than in mucinous adenocarcinomas. Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared with mucinous tumors is related to the difference in their histological characteristics.  相似文献   
82.

Background

To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease.

Methods

PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome).

Results

Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5–86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10–107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05–30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases.

Conclusions

Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation.  相似文献   
83.
BackgroundAlthough oxitropium bromide is used clinically as an anticholinergic drug (i.e., parasympathetic antagonist) to relax airway smooth muscle, we examined whether it has or does not have any effects on diaphragm muscle.MethodsThree treatment sets, an oxitropium bromide inhalation only group, an oxitropium bromide inhalation plus endotoxin injection group (in vivo) and an oxitropium bromide incubation group (in vitro) were studied as to diaphragm muscle contractile properties.ResultsOxitropium bromide inhalation shifted force-frequency curves upward at 2 h after inhalation (p < 0.05) and inhibited the decrease of force-frequency curves due to endotoxin injection in vivo. Incubation with oxitropium bromide of untreated diaphragm muscle and diaphragm muscle injected with endotoxin did not increase the force-frequency curves dose-dependently in vitro; however, it caused both types of muscle to be fatigue resistant.ConclusionsWe speculate that the increment of muscle contractility with the inhalation of oxitropium bromide was induced by the antagonization of musucarinic acetylcholine receptors (mAChR). In addition, the changes of fatigue resistance provoked by oxitropium bromide, which also is speculated to antagonize mAChR, may be beneficial in the treatment of patients with COPD.  相似文献   
84.
Abstract

Different approaches have been developed to improve the scaffold properties that provide structural support and biological interaction to achieve the desired environment for tissue regeneration. We previously reported that addition of human fibroblast growth factor 18 (hFGF18) to acryloyl group-modified cholesterol-bearing pullulan (CHPOA) nanogel-crosslinked (NanoClik) hydrogels that contain human bone morphogenetic protein 2 (hBMP2) stabilized bone healing in mouse calvarial defect model. In this study, we evaluated the use of disc-shaped dried nanogel-crosslinked gel as carriers of growth factors in order to seek possible clinical application in future. Both conventionally-dried NanoClik disc and nanogel-crosslinked porous (NanoCliP) disc made by freeze-drying that contained the growth factors induced bone healing but not as much as with NanoClik hydrogel application but addition of RGD peptides (RGD-NanoCliP disc) improved the healing. All type of discs showed the same biphasic ovalbumin-Alexa Fluor 488 protein release profile in vitro, an initial burst followed by a gradual sustained release more than one week, which was confirmed in vivo. Histological analysis showed remarkable new bone formation with more calcification in RGD-NanoCliP disc with the growth factors and the osteogenesis appeared to begin in the dura mater in contact with the disc. These observations suggest: (1) the fitness of the durable discs to the bone defect is a critical factor for bone healing, which is supplemented by addition of RGD peptides, (2) the porosity is suitable for osteoblast recruitment, (3) growth factor release pattern of the CHPOA nanogel based gels is ideal for bone healing.  相似文献   
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The regulation of uterine and circulating peripheral blood natural killer (NK) cells has been associated with reproductive immunology such as recurrent pregnancy losses, implantation failures, or preeclampsia. Preeclampsia is a hypertensive disorder of pregnancy characterized by increased blood pressure accompanied by proteinuria and is a major cause of maternal and fetal mortality. Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. The relation of NCRs to reproduction is not fully characterized yet. The different profile of NCRs expression may suggest presence of abnormal regulation of NK cell in women with reproductive failures. Pregnant women with preeclampsia carry immunological abnormalities of NCRs on peripheral blood NK cells during pregnancy. The lower expression of NKp46+ NK cells in women with preeclampsia may account for the higher production of NK1 cytokine that is known as NK1 shift in pregnant women with preeclampsia. Evaluation of NKp46 on peripheral blood NK cells may be applicable to find the onset of preeclampsia. In this review, various expressions of NK cell surface markers including NCRs on NK cells, NK cell cytotoxicity, and production of cytokines and angiogenic factors by NK cells were reviewed in relation to preeclampsia.  相似文献   
88.
Lysophosphatidic acid (LPA) mediates a wide range of biological responses with G protein-coupled transmembrane receptors (LPA receptors). So far, at least six types of LPA receptors (LPA receptor-1 (LPA1) to LPA6) have been identified. Recently, it has been reported that LPA3 indicates opposite effects on cellular functions of cancer cells. In the present study, to assess a biological role of LPA3 on cell migration ability of colon cancer cells, we generated LPA receptor-3 (LPAR3) knockdown (HCT-sh3-3) cells from HCT116 and measured cell motile and invasion activities. In motility assay with a cell culture insert, HCT-sh3-3 cells showed significantly high cell motile activity, compared with control cells. For invasion assay, the filter was coated with Matrigel. The invasive activity of HCT-sh3-3 cells was significantly higher than that of control cells. Furthermore, we also examined the effects of LPAR3 knockdown on the interaction between colon cancer cells and endothelial F-2 cells. When F-2 cells were cultured with serum-free DMEM containing a supernatant from HCT-sh3-3 cells, the cell growth rate and migration activity of F-2 cells were significantly stimulated, associating with the elevated expressions of vascular endothelial growth factor (VEGF)-A and VEGF-C genes in HCT-sh3-3 cells. These results suggest that LPA3 may act as a negative regulator on cell motile and invasive abilities of colon cancer HCT116 cells.  相似文献   
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