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Olfactory bulbectomy (OBX) in mice elicits impaired memory and cognitive functions. Here, we found that chronic oral administration of spiro[imidazo[1,2-a]pyridine-3,2-indan]-2(3H)-one (ZSET1446/ST101) (0.1-1 mg/kg/day), a novel cognitive enhancer, significantly improved memory deficits as assessed by Y-maze and novel object recognition tasks in OBX mice. Immunostaining of cholinergic neurons in the medial septum by using an anti-choline acetyltransferase antibody indicated that chronic ZSET1446 treatment did not rescue cholinergic neurons. However, chronic treatment significantly restored OBX-induced decreases both in calcium/calmodulin-dependent protein kinase II (CaMKII) and protein kinase C (PKC) phosphorylation without improving decreased extracellular signal-regulated kinase phosphorylation in the hippocampal CA1 region. Consistent with enhanced CaMKII and PKC phosphorylation, ZSET1446 treatment improved glutamate receptor 1 (Ser-831) phosphorylation in the hippocampal CA1 region. ZSET1446 treatment also significantly rescued impaired long-term potentiation (LTP) in the hippocampal CA1 region of OBX mice. Taken together, the cognition-enhancing effect of ZSET1446 is probably mediated in part by stimulation of CaMKII and PKC activities, which in turn rescue impaired hippocampal LTP in OBX mice.  相似文献   
23.
Adrenomedullin (AM) is a novel vasodilating peptide involved in the regulation of circulatory homeostasis and implicated in the pathophysiology of cardiovascular disease. We tested the hypothesis that AM also possesses angiogenic properties. Using laser Doppler perfusion imaging, we found that AM stimulated recovery of blood flow to the affected limb in the mouse hind-limb ischemia model. AM exerted this effect in part by promoting expression of vascular endothelial growth factor (VEGF) in the ischemic limb, and immunostaining for CD31 showed the enhanced flow to reflect increased collateral capillary density. By enhancing tumor angiogenesis, AM also promoted the growth of subcutaneously transplanted sarcoma 180 tumor cells. However, heterozygotic AM knockout mice (AM+/-) showed significantly less blood flow recovery with less collateral capillary development and VEGF expression than their wild-type littermates. Similarly, mice treated with AM22-52, a competitive inhibitor of AM, showed reduced capillary development, and growth of sarcoma 180 tumors was inhibited in AM+/- and AM22-52-treated mice. Notably, administration of VEGF or AM rescued blood flow recovery and capillary formation in AM+/- and AM22-52-treated mice. In cocultures of endothelial cells and fibroblasts, AM enhanced VEGF-induced capillary formation, whereas in cultures of endothelial cells AM enhanced VEGF-induced Akt activation. These results show that AM possesses novel angiogenic properties mediated by its ability to enhance VEGF expression and Akt activity. This may make AM a useful therapeutic tool for relieving ischemia; conversely, inhibitors of AM could be useful for clinical management of tumor growth.  相似文献   
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Methicillin-resistant Staphylococcus aureus (MRSA) is highly contagious. It is spread by direct contact with MRSA-infected people or objects. Healthcare workers' hands are the most common vehicle for the transmission of healthcare-associated pathogens from patient to patient and within the healthcare environment. The present study aimed to investigate the correlation between the incidence of MRSA among Staphylococcus aureus recovered from clinical culture and the use of alcohol-based hand rub solutions or gloves and antimicrobial use density (AUD). All data were examined every 6 months between January 2005 and June 2008. The increasing use of alcohol-based hand rub solutions was correlated with a decreasing incidence of recovery of MRSA from clinical cultures (r(2) = 0.58). A statistically significant (P < 0.05) correlation (r(2) = 0.68) was observed between glove use and the incidence of MRSA. On the other hand, we did not find any correlation between the AUD of each antibiotic group and the incidence of MRSA. Thus, we suggest that it is important to use not only alcohol-based hand rubs, but also gloves, because MRSA is transmitted from patient to patient by the hands of healthcare workers.  相似文献   
26.
A 68-year-old woman suffering from a left iliac tumor and severe back pain was admitted to another hospital in May 1999. The bone X-ray, CT scan and MRI demonstrated a 7 cm x 5 cm left iliac tumor with osteolysis and she was transferred to our hospital. Angiography demonstrated multiple hypervascular lesions in the left ilium, lumbar vertebrae, left ischium, left pubis and left rib. The tumor was resected and diagnosed as a plasmacytoma. Immunoelectrophoresis did not show any M-protein in the serum and urine, but the patient was diagnosed as having a non-secretory or low producing multiple myeloma because of the presence of 42.8% of abnormal plasma cells in the bone marrow aspirate. Her symptoms improved following 3 courses of MCNU-VMP therapy and the bone marrow plasma cells decreased to less than 5%. She was discharged and treated as an outpatient but relapsed and died of chemotherapy-resistant myeloma. We report this case because macro-angiogenesis in a multiple myeloma demonstrated by angiography is rare and interesting.  相似文献   
27.
Rho-associated kinase (ROCK) is a downstream effector of small Rho-GTPases, and phosphorylates several substrates to regulate cell functions, including actin cytoskeletal reorganization and cellular motility. Endothelial-mesenchymal transformation (EMT) is a critical event in the formation of valves and septa during cardiogenesis. It has been reported that ROCK plays an important role in the regulation of endocardial cell differentiation and migration during mouse cardiogenesis (Zhao and Rivkees [2004] Dev. Biol. 275:183-191). Immunohistochemistry showed that, during chick cardiogenesis, ROCK1 and -2 were expressed in the transforming and migrating endothelial/mesenchymal cells in the outflow tract (OT) and atrioventricular (AV) canal regions from which valvuloseptal endocardial cushion tissue would later develop. Treatment with Y27632, a specific ROCK inhibitor, of cultured AV explants or AV endothelial monolayers of stage 14-minus heart (preactivated stage for EMT) on three-dimensional collagen gel perturbed the seeding of mesenchymal cells into the gel lattice. In these experiments, Y27632 did not suppress the expression of an early transformation marker, smooth muscle alpha-actin. Moreover, Y27632 inhibited the mesenchymal invasion in stage 14-18 AV explants, in which endothelial cells had committed to undergo EMT. ML-9, a myosin light chain kinase inhibitor, also inhibited the mesenchymal invasion in cultured AV explants. These results suggest that ROCKs have a critical role in the mesenchymal cell invasion/migration that occurs at the late onset of EMT.  相似文献   
28.
Blue rubber bleb nevus syndrome (BRBNS) is a rare disorder showing venous malformations in the skin and gastrointestinal tract, and other internal organs. We encountered a patient with BRBNS in whom hemangiomas of the uterine cervix appeared during pregnancy. This was apparently the first reported occurrence. To avoid unexpected bleeding from hemangiomas, patients with BRBNS should be examined repeatedly for hemangiomas of the birth canal, and special care should be taken in deciding the mode of delivery.  相似文献   
29.
Intrahepatic bile ducts (IHBDs) are indispensable for transporting bile secreted from hepatocytes to the hepatic duct. The biliary epithelial cells (BECs) of the IHBD arise from bipotent hepatoblasts around the portal vein, suggesting the portal mesenchyme is essential for their development. However, except for Notch or Activin/TGF-beta signaling molecules, it is not known which molecules regulate IHBD development. Here, we found that FGF receptors and BMP4 are specifically expressed in the developing IHBD and the hepatic mesenchyme, respectively. Using a mesenchyme-free culture of liver bud, we showed that bFGF and FGF7 induce the hepatoblasts to differentiate into BECs, and that BMP4 enhances bFGF-induced BEC differentiation. The extracellular matrix (ECM) components in the hepatic mesenchyme induced BEC differentiation. Forced expression of a constitutively active form of the FGF receptor partially induced BEC differentiation markers in vivo. These data strongly suggest that bFGF and FGF7 promote BEC differentiation cooperatively with BMP4 and ECMs in vivo.  相似文献   
30.
Type 2 diabetes mellitus is a complex metabolic disorder in which endogenous sex hormones may contribute to sex-dependent etiologies. We hypothesized that genetic variants related to type 2 diabetes mellitus might differ between men and women. We thus performed a large-scale association study to identify gene polymorphisms associated with type 2 diabetes mellitus in men and women separately. The study population comprised 4854 unrelated Japanese individuals (2688 men, 2166 women), including 1490 subjects with type 2 diabetes mellitus (969 men, 521 women). The genotypes for 16 gene polymorphisms were determined with a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Multivariable logistic regression analysis with adjustment for age, body mass index, and smoking status revealed that the T-->G (3' UTR) polymorphism of the thrombospondin 2 gene (THBS2), the -603A-->G polymorphism of the coagulation factor III gene (F3), and the G-->T (intron 2) polymorphism of the adipocyte, C1Q, and collagen domain containing (adiponectin) gene (ADIPOQ) were significantly associated with the prevalence of type 2 diabetes mellitus in men, and that the A-->G (Arg160Gly) polymorphism of the paraoxonase 1 gene (PON1) was significantly associated with this condition in women. A stepwise forward selection procedure demonstrated that genotypes of THBS2, F3, and ADIPOQ were significant determinants of type 2 diabetes mellitus in men, and that genotype of PON1 significantly affected this condition in women. Genotyping of these polymorphisms may prove informative for assessment of the genetic component of type 2 diabetes mellitus for men and women separately.  相似文献   
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