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IntroductionA proper cavernous endothelial cell culture system would be advantageous for the study of the pathophysiologic mechanisms involved in endothelial dysfunction and erectile dysfunction (ED).AimTo establish a nonenzymatic technique, which we termed the “Matrigel‐based sprouting endothelial cell culture system,” for the isolation of mouse cavernous endothelial cells (MCECs) and an in vitro model that mimics in vivo situation for diabetes‐induced ED.MethodsFor primary MCEC culture, mouse cavernous tissue was implanted into Matrigel and sprouting cells from the tissue were subcultivated. To establish an in vitro model for diabetes‐induced ED, the primary cultured MCECs were exposed to a normal‐glucose (5 mmoL) or a high‐glucose (30 mmoL) condition for 48 hours.Main Outcome MeasuresThe purity of isolated cells was determined by fluorescence‐activated cell sorting analysis. MCECs incubated under the normal‐ or the high‐glucose condition were used for Western blot, cyclic guanosine monophosphate (cGMP) quantification, and in vitro angiogenesis assay.ResultsWe could consistently isolate high‐purity MCECs (about 97%) with the Matrigel‐based sprouting endothelial cell culture system. MCECs were subcultured up to the fifth passage and no significant changes were noted in endothelial cell morphology or purity. The phosphorylation of Akt and eNOS and the cGMP concentration were significantly lower in MCECs exposed to high glucose than in those exposed to normal glucose. MCECs exposed to the normal‐glucose condition formed well‐organized capillary‐like structures, whereas derangements in tube formation were noted in MCECs exposed to high glucose. The protein expression of transforming growth factor‐β1 (TGF‐β1) and phospho‐Smad2 was significantly increased by exposure to high glucose.ConclusionThe Matrigel‐based sprouting endothelial cell culture system is a simple, technically feasible, and reproducible technique for isolating pure cavernous endothelial cells in mice. An in vitro model for diabetic ED will be a valuable tool for evaluating the angiogenic potential of novel endogenous or synthetic modulators. Yin GN, Ryu J‐K, Kwon M‐H, Shin SH, Jin HR, Song K‐M, Choi MJ, Kang D‐Y, Kim WJ, and Suh J‐K. Matrigel‐based sprouting endothelial cell culture system from mouse corpus cavernosum is potentially useful for the study of endothelial and erectile dysfunction related to high‐glucose exposure. J Sex Med 2012;9:1777–1789.  相似文献   
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The computational fluid dynamics methods for the limited flow rate and the small dimensions of an intracranial artery stenosis may help demonstrate the stroke mechanism in intracranial atherosclerosis. We have modeled the high wall shear stress (WSS) in a severe M1 stenosis. The high WSS in the systolic phase of the cardiac cycle was well-correlated with a thick fibrous cap atheroma with enhancement, as was determined using high-resolution plaque imaging techniques in a severe stenosis of the middle cerebral artery.  相似文献   
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A case of bacteremia caused by Pediococcus acidilactici occurring in a patient with metastatic adenocarcinoma of the gallbladder is described. The bacteremia persisted despite an antimicrobial regimen of vancomycin, ciprofloxacin, metronidazole, and caspofungin. Within 36 h of switching the vancomycin to daptomycin (6 mg/kg per day), the bacteremia resolved and the patient improved clinically. Previous reports of human pediococcal infection are also reviewed.  相似文献   
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Nitric oxide (NO) is an important biomolecule for regulating various brain functions, such as the control of neurovascular tone. NO, however, cannot be stored inside cells where NO is produced and immediately diffuses through the cellular membrane and decays rapidly, which makes the detection of NO extremely hard in an in vivo setting. We constructed an amperometric NO nanosensor and utilized it to directly measure NO release in the living brain. The NO nanosensor uses nanopores (pores with an opening radii <500 nm) in which NO is oxidized at the porous platinum surface. The nanopore-based sensor was inserted vertically into the brains of anesthetized mice up to the end of the hippocampal CA 3 region, or to a depth of about 3 mm. The sensor was slowly advanced in the brain in 0.5 μm increments and in 0.05 s temporal steps. Different levels of NO release were monitored by the nanopore NO sensor during the course of the penetration. The hippocampal CA3 region had the highest level of NO release, which was followed by CA2 and CA1 of the hippocampus and the cortex. The levels of NO release were not uniformly distributed within the cortical and hippocampal areas of living brain. In sum, the nanopore-based NO sensor was able to grossly measure NO contents within living brain in real time and with high sensitivity. This study may provide good insights about the relationship between the distributions of NOS-immunoreactive neurons and the directly measured levels of NO release in brain.  相似文献   
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The shortage of donor organs occasionally mandates the use of hepatic allografts from anti-HBc (+) donors. HBIG and/or lamivudine are recommended for the prevention of de novo HBV infection in naive patients, but there are attendant problems, such as mutant strain emergence and high cost. Active immunization presents a better alternative than the use of HBIG or lamivudine, if it can be proven to be effective. Accordingly, we investigated the outcome of HBV vaccination in pediatric hepatic transplant recipients. Between July 1999 and October 2001, 19 pediatric recipients were administered HBV vaccinations after liver transplantation at Seoul National University Hospital. Nine patients received a graft from anti-HBc (+) donors and 10 from anti-HBc (-) donors. When steroid was withdrawn, recombinant HBV vaccine was administered. The median follow-up period after vaccination was 10.0 +/- 5.2 months. Seventeen of the 19 patients showed a positive response to vaccination. In 9 patients who received grafts from anti-HBc (+) donors, 2 patients showed no response, 4 patients low response (peak HBsAb titer <1,000 IU/L), and 3 patients high response (peak HBsAb titer >/=1,000 IU/L). De novo HBV infection developed in 1 of 2 patients who showed no response to vaccination. In 10 patients who received grafts from anti-HBc (-) donors, 5 showed a low response and 5 a high response. In conclusion, HBV vaccination in pediatric patients after liver transplantation appeared to exhibit some effectiveness at protecting young children that received a graft from anti-HBc (+) donors from de novo HBV infection.  相似文献   
99.
Sulfonylureas are widely used as an antidiabetic drug. In the present study, the effects of sulfonylurea administered supraspinally on immobilization stress-induced blood glucose level were studied in ICR mice. Mice were once enforced into immobilization stress for 30 min and returned to the cage. The blood glucose level was measured 30, 60, and 120 min after immobilization stress initiation. We found that intracerebroventricular (i.c.v.) injection with 30 µg of glyburide, glipizide, glimepiride or tolazamide attenuated the increased blood glucose level induced by immobilization stress. Immobilization stress causes an elevation of the blood corticosterone and insulin levels. Sulfonylureas pretreated i.c.v. caused a further elevation of the blood corticosterone level when mice were forced into the stress. In addition, sulfonylureas pretreated i.c.v. alone caused an elevation of the plasma insulin level. Furthermore, immobilization stress-induced insulin level was reduced by i.c.v. pretreated sulfonylureas. Our results suggest that lowering effect of sulfonylureas administered supraspinally against immobilization stress-induced increase of the blood glucose level appears to be primarily mediated via elevation of the plasma insulin level.  相似文献   
100.
The purpose of this study was to examine the prognostic significance of insulin‐like growth factor‐1 receptor (IGF‐1R) expression alone and in relation to the expression of the MET‐ receptor and the MET‐homologous receptor RON, in classical Hodgkin's lymphoma (cHL). Tumour samples from patients with cHL (n = 202; median age 37.5 years) were analysed retrospectively for IGF‐R1, MET or RON expression by immunohistochemistry using tissue microarrays. The median follow‐up time was 3.7 years (range, 0.1–20 years). Twenty‐nine patients (14.3%) expressed IGF‐1R protein in Hodgkin/Reed–Sternberg (HRS) cells, which was associated with a better overall survival (OS) (= 0.036). IGF‐1R expression was closely associated with MET receptor expression and low level of lactate dehydrogenase. In patients with cHL receiving doxorubicin, bleomycin, vinblastine and dacarbazine, those expressing IGF‐1R showed a trend towards better OS and event‐free survival than IGF‐1R‐negative patients (= 0.129 and = 0.115 respectively), but statistical significance was not reached. This study suggests that IGF‐1R expression could be associated with better clinical outcome in cHL but is significantly associated with the expression of MET receptor.  相似文献   
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