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61.
BACKGROUNDS: Fibroblast growth factor 8-isoform b (FGF8b) has been detected in human clinical sex-organ related cancers including hormone-refractory prostate cancer. There are, however, few relevant experimental models. A murine monoclonal anti-FGF8 antibody, KM1334, has been shown to neutralize FGF8b and inhibit the growth of androgen-dependent mouse mammary SC-3 cells in vitro and in vivo. In the present study, we evaluated the anti-tumor activity of KM1334 against androgen-dependent and -independent progression of FGF8b-expressing human prostate cancer xenografts. METHODS: FGF8b cDNA was transfected into androgen-dependent human prostate cancer cell line LNCaP, and its xenograft tumors were established subcutaneously in SCID mice with or without castration. KM1334 at the dose of 400 microg/head was injected twice weekly. RESULTS: FGF8b-expressing LNCaP cells secreted FGF8b, showed enhanced level of Erk1/2 phosphorylation, and showed more potent growth properties than mock-expressing cells in vitro and in vivo. KM1334 reduced these properties in vitro, inhibited tumorigenecity in vivo (T/C=0.33), and showed anti-tumor activity against established tumors (T/C=0.47) of FGF8b-expressing cells. FGF8b-expressing LNCaP tumors were androgen-dependent. However, they recurred as androgen-independent FGF8b positive tumors after castration. KM1334 also inhibited the growth of established FGF8b-expressing tumors in the androgen-independent states (T/C=0.47). CONCLUSIONS: These results indicate that humanized monoclonal antibodies, conserving the paratope of KM1334, are a promising candidate for therapy of FGF8b-expressing clinical prostate cancers. Follow-up studies using xenograft models with clinical FGF8b-expressing tumors are required to validate these early findings.  相似文献   
62.
We report a successful complex mitral valve plasty using port access minimally invasive cardiac surgery for congenital mitral regurgitation that presented as an abnormality of the subvalvular apparatus. A 16-year-old male patient received a diagnosis of mitral regurgitation resulting from tethering of the anterior mitral leaflet and posterior mitral leaflet caused by an abnormality in papillary muscle insertion and a hypoplastic chordae tendineae. The posterior leaflet was closely tethered to the tips of the papillary muscle with essentially no chordae tendineae. The flexibility of the leaflet was restored by surgically removing the abnormal chordae, and reconstruction of chordae tendinae of the anterior leaflet was carried out using three loops and of the posterior leaflet using one loop with a loop technique method. As an additional procedure for persistent regurgitation, an edge-to-edge technique to the posterior commissure side was performed, after which the mitral regurgitation disappeared.  相似文献   
63.
We report herein a case of spontaneous rupture of the pancreaticoduodenal artery (PDA) associated with obstruction of the common hepatic artery. A 68-year-old man was admitted to our hospital following the sudden onset of severe upper abdominal pain. Computed tomography revealed a large mass formation in the peritoneal cavity. Hemorrhagic shock rapidly developed during the initial evaluation, necessitating an exploratory laparotomy to be performed in the emergency room. This revealed a large hematoma in the retroperitoneal space, and a ruptured PDA was sutured. Postoperative angiography showed obstruction of the common hepatic artery and also suggested that the source of the bleeding was the PDA. Thus, a diagnosis of spontaneous rupture of a PDA aneurysm associated with occlusion of the common hepatic artery was made. Following this case report, we discuss the development of true aneurysms of the PDA and the treatment of ruptured true PDA aneurysms resulting in shock. Received: September 18, 2000 / Accepted: July 17, 2001  相似文献   
64.
BACKGROUND: Ischemia/reperfusion (I/R) injury is closely associated with tissue damage in various organs, as well as in kidney transplants. Erythropoietin (EPO) has been shown to have a cytoprotective effect against hypoxia. We examined the effect of EPO against renal I/R injury and the underlying mechanism. METHODS: Human umbilical vein endothelial cells and human renal proximal tubular epithelial cells were cultured under hypoxic conditions with various EPO concentrations at 37 degrees C and examined the mechanism of cell proliferation by EPO. Moreover, to demonstrate the renoprotective effect in vivo, we treated Sprague-Dawley rats with 100 IU/kg EPO every 2 days for 2 weeks (a total of 6 doses). One day after the last injection, the operations to produce renal I/R injury (bilateral renal occlusion for 60 min) were done, and rats were killed at the end of the reperfusion period (24 hr and 72 hr after reperfusion began). RESULTS: First, we demonstrated in vitro that EPO increased hypoxia inducible factor-1alpha (HIF-1alpha) expression and stimulated proliferation of both cells under hypoxic conditions. Next, we demonstrated in vivo that EPO treatment increased the number of HIF-1alpha-positive cells, and markedly induced the expression of vascular endothelial growth factor messenger RNA. Using pimonidazole, a molecular probe that detects hypoxia, we found that EPO markedly attenuated tubular hypoxia, and reduced the number of terminal transferase dUTP nick end labeling-positive apoptotic cells and alpha-smooth muscle actin-positive interstitial cells. CONCLUSIONS: We suggested a novel HIF-1alpha induction pathway by EPO under hypoxic conditions. Thus, EPO may protect the kidneys against ischemia reperfusion injury by activating HIF-1alpha.  相似文献   
65.

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   
66.
Owing to the severe shortage of cadaveric grafts in Japan, we have performed ABO-incompatible living donor kidney transplantation since 1989. This study assessed short- and long-term outcomes in 441 patients who received ABO-incompatible living donor kidney transplants between January 1989 and December 2001. We compared our results with historical data from 1055 recipients of living kidney transplantation. Overall patient survival rates 1, 3, 5, 7, and 9 years after ABO-incompatible transplantation were 93%, 89%, 87%, 85%, and 84%, respectively. Corresponding overall graft survival rates were 84%, 80%, 71%, 65%, and 59%. After ABO-incompatible transplantation, graft survival rates were significantly higher in patients 29 years or younger than in those 30 years or older and in patients who received anticoagulation therapy than in those who did not receive such therapy. There were no significant differences between A-incompatible and B-incompatible recipients with respect to clinical outcomes. The graft survival rate at 1 year in the historical controls was slightly but not significantly higher than that in our recipients of ABO-incompatible transplants. We conclude that long-term outcome in recipients of ABO-incompatible living kidneys is excellent. Transplantation of ABO-incompatible kidneys from living donors is a radical, but effective treatment for end-stage renal disease.  相似文献   
67.
This study reports the results for 10 patients with recurrent hemarthrosis after knee joint arthroplasty. The average interval between arthroplasty and the first instance of hemarthrosis was at 26 months, and the average number of hemarthroses per patient was 3.8. In 3 patients, the bleeding responded to simple conservative measures. The remaining 7 needed surgery; there were 6 arthroscopic synovectomies and 1 polyethylene revision. Impingement of the proliferative synovium was observed in only 2 patients during surgical intervention. In the 2 patients in whom arthroscopic management was successful, another procedure with an electric coagulator, in addition to a formal synovectomy, was performed. The use of a coagulator may be helpful for direct coagulation when arthroscopic management is selected, although open synovectomy is curative in most cases.  相似文献   
68.
We investigated whether mesenchymal stem cells (MSCs) in synovial fluid (SF) increased in the knee with degenerated cartilage and osteoarthritis. SF was obtained from the knee joints of 22 patients with anterior cruciate ligament (ACL) injury during ACL reconstruction, and cartilage degeneration was evaluated arthroscopically. SF was also obtained from the knee joints of 6 healthy volunteers, 20 patients with mild osteoarthritis, and 26 patients with severe osteoarthritis, in which the grading was evaluated radiographically. The cell component in the SF was cultured for analyses. Synovium (SYN) and bone marrow (BM) were also harvested during total knee arthroplasties. The MSC number in SF was correlated with the cartilage degeneration score evaluated by arthroscopy. The MSC number in the SF was hardly noticed in normal volunteers, but it increased in accordance with the grading of osteoarthritis. Though no significant differences were observed regarding surface epitopes, or differentiation potentials, the morphology and gene profiles in SF MSCs were more similar to those in SYN MSCs than in BM MSCs. We listed 20 genes which were expressed higher in both SYN MSCs and SF MSCs than in BM MSCs, and 3 genes were confirmed by quantitative RT-PCR. MSCs in SF increased along with degenerated cartilage and osteoarthritis.  相似文献   
69.

Background

The tissue-protective effects of erythropoietin (EPO) have been extensively investigated, and EPO administration can raise the hemoglobin (Hb) concentration. Recently, we reported that carbamylated erythropoietin (CEPO) protected kidneys from ischemia-reperfusion injury as well as EPO.

Methods

To investigate the clinical applications of CEPO, we next evaluated the long-term therapeutic effect of CEPO using a tubulointerstitial model rat. We randomized remnant kidney model rats to receive saline, EPO, or CEPO for 8?weeks.

Results

CEPO- and EPO-treated rats had improved serum creatinine levels compared with saline-treated remnant kidney model rats, although the Hb level was significantly increased in EPO-treated rats. Two-photon microscopy revealed that EPO/CEPO significantly ameliorated tubular epithelial cell damage assessed by endocytosis. In addition, CEPO or EPO protected endothelial cells with a sustained blood flow rate. EPO or CEPO suppressed the number of TUNEL-positive apoptotic cells with weak ??SMA staining. Furthermore, PCR analysis demonstrated that TGF-?? and type I collagen expression was attenuated in EPO- or CEPO-treated rats, accompanied by a significant decrease in interstitial fibrosis.

Conclusion

We established a long-term therapeutic approach to protect tubulointerstitial injury with CEPO, and thus, the therapeutic value of this approach warrants further attention and preclinical studies.  相似文献   
70.
BACKGROUND: Nephrotoxic glomerulonephritis is induced by the administration of antibody against the glomerular basement membrane (GBM). We demonstrated previously that Fc receptors for immunoglobulin G (IgG) (FcgammaR) play crucial roles in the induction of accelerated nephrotoxic glomerulonephritis by using FcRgamma-deficient (-/-) mice. Since FcRgamma-/- mice lack the cell surface expression of two activating FcgammaRs, FcgammaRI and FcgammaRIII. The present study aims to identify the FcgammaR responsible for the induction of nephrotoxic glomerulonephritis. METHODS: Accelerated anti-GBM glomerulonephritis was induced in FcgammaRI-/-, FcgammaRIII-/-, and FcRgamma-/- mice by preimmunization with rabbit IgG followed by inoculation of rabbit anti-GBM antibody. Histologic analysis and immunostaining of renal sections were performed. RESULTS: FcgammaRI-/- mice as well as wild-type mice showed severe glomerulonephritis with hypernitremia by the administration of anti-GBM antibody. In contrast, FcgammaRIII-/- mice showed much milder renal involvement, similar to FcRgamma-/- mice. Histologically, FcgammaRI-/- mice showed intracapillary proliferation, glomerular thrombosis, and crescent formation, whereas FcgammaRIII-/- mice showed only glomerular hypercellular changes. The depositions of anti-GBM antibodies, autologous antibodies and complement C3 along the GBM were equally observed among all three FcR-/- mouse types by immunostaining. CONCLUSIONS: Accelerated nephrotoxic glomerulonephritis is induced predominantly through FcgammaRIII but not FcgammaRI.  相似文献   
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