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41.
Kallmann’s syndrome is a rare genetic disorder due to abnormal migration of olfactory axons and gonadotropin releasing hormone producing neurons, characterized by hypogonadism and anosmia. The prevalence of Kallmann’s syndrome is 1:10,000 to 1:60,000 with a male to female ratio of 5:1. The inheritance of Kallmann’s syndrome may be X-linked, autosomal recessive or autosomal dominant with variable penetrance, mutation involving KAL-1 and KAL-2 gene respectively. We report a case of Kallmann’s syndrome in a 19-year-old boy with characteristic clinical, biochemical and MRI findings.  相似文献   
42.
Abnormal choline phospholipid metabolism is associated with oncogenesis and tumor progression. We have investigated the effects of targeting choline phospholipid metabolism by silencing two glycerophosphodiesterase genes, GDPD5 and GDPD6, using small interfering RNA (siRNA) in two breast cancer cell lines, MCF‐7 and MDA‐MB‐231. Treatment with GDPD5 and GDPD6 siRNA resulted in significant increases in glycerophosphocholine (GPC) levels, and no change in the levels of phosphocholine or free choline, which further supports their role as GPC‐specific regulators in breast cancer. The GPC levels were increased more than twofold during GDPD6 silencing, and marginally increased during GDPD5 silencing. DNA laddering was negative in both cell lines treated with GDPD5 and GDPD6 siRNA, indicating absence of apoptosis. Treatment with GDPD5 siRNA caused a decrease in cell viability in MCF‐7 cells, while GDPD6 siRNA treatment had no effect on cell viability in either cell line. Decreased cell migration and invasion were observed in MDA‐MB‐231 cells treated with GDPD5 or GDPD6 siRNA, where a more pronounced reduction in cell migration and invasion was observed under GDPD5 siRNA treatment as compared with GDPD6 siRNA treatment. In conclusion, GDPD6 silencing increased the GPC levels in breast cancer cells more profoundly than GDPD5 silencing, while the effects of GDPD5 silencing on cell viability/proliferation, migration, and invasion were more severe than those of GDPD6 silencing. Our results suggest that silencing GDPD5 and GDPD6 alone or in combination may have potential as a new molecular targeting strategy for breast cancer treatment. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
43.
This work describes the development and testing of poly(ethylene glycol) (PEG) hydrogels with independently controlled dimensions of wide and deep macrochannels for their ability to promote alignment of skeletal myoblasts and myoblast differentiation. A UV-photopatterned thiol-ene mold was employed to produce long channels, which ranged from ~40 to 200 μm in width and from ~100 to 200 μm in depth, within a PEG-RGD hydrogel. Skeletal myoblasts (C2C12) were successfully cultured multiple cell layers deep within the channels. Decreasing channel width, increasing channel depth and, interestingly, increasing cell layer away from the channel base all contributed to a decreased interquartile range of cell angle relative to the long axis of the channel wall, indicating improved cell alignment. Differentiation of skeletal myoblasts into myotubes was confirmed by gene expression for myoD, myogenin and MCH IIb, and myotube formation for all channel geometries, but was not dependent on channel size. Qualitatively, myotubes were characteristically different, as myotubes were larger and had more nuclei in larger channels. Overall, our findings demonstrate that relatively large features, which do not readily facilitate cell alignment in two dimensions, promote cell alignment when presented in three dimensions, suggesting an important role for three-dimensional spatial cues.  相似文献   
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The objective of this study was to compare the morphological and chemical composition of bone graft (BG) and coral graft (CG) as well as their osteogenic differentiation potential using rabbit mesenchymal stem cells (rMSCs) in vitro. SEM analysis of BG and CG revealed that the pores in these grafts were interconnected, and their micro-CT confirmed pore sizes in the range of 107-315 µm and 103-514 µm with a total porosity of 92% and 94%, respectively. EDS analysis indicated that the level of calcium in CG was relatively higher than that in BG. FTIR of BG and CG confirmed the presence of functional groups corresponding to carbonyl, aromatic, alkyl, and alkane groups. XRD results revealed that the phase content of the inorganic layer comprised highly crystalline form of calcium carbonate and carbon. Atomic force microscopy analysis showed CG had better surface roughness compared to BG. In addition, significantly higher levels of osteogenic differentiation markers, namely, alkaline phosphatase (ALP), Osteocalcin (OC) levels, and Osteonectin and Runx2, Integrin gene expression were detected in the CG cultures, when compared with those in the BG cultures. In conclusion, our results demonstrate that the osteogenic differentiation of rMSCs is relatively superior in coral graft than in bone graft culture system.  相似文献   
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Platelet activation and thrombus formation have been implicated to be detrimental for intraportal pancreatic islet transplants. The platelet-specific collagen receptor glycoprotein VI (GPVI) plays a key role in thrombosis through cellular activation and the subsequent release of secondary mediators. In aggregometry and in a microfluidic dynamic assay system modeling flow in the portal vein, pancreatic islets promoted platelet aggregation and triggered thrombus formation, respectively. While platelet GPVI deficiency did not affect the initiation of these events, it was found to destabilize platelet aggregates and thrombi in this process. Interestingly, while no major difference was detected in early thrombus formation after intraportal islet transplantation, genetic GPVI deficiency or acute anti-GPVI treatment led to an inferior graft survival and function in both syngeneic mouse islet transplantation and xenogeneic human islet transplantation models. These results demonstrate that platelet GPVI signaling is indispensable in stable thrombus formation induced by pancreatic islets. GPVI deficiency resulted in thrombus destabilization and inferior islet engraftment indicating that thrombus formation is necessary for a successful intraportal islet transplantation in which platelets are active modulators.  相似文献   
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Dental implantology is the state of the art technique to replace missing teeth. Implant stability of implant jeopardizes its longevity and success of treatment. This study evaluates the implant stability of implant before and after 4 months of the implant placement, but before prosthetically loading it. Ten two-stage implants of Life care and Nobel Biocare dental implants were placed in 20 patients. Digital OPG was taken on the day of implant placement. After 4 months, at the time of second stage surgery, the implant stability was evaluated by the Periotest instrument. Four months after the implant placement, Periotest evaluation showed a mean of 1.9, which indicated that implants were well osseointegrated and stable. Even before prosthetically loading the two-stage implant, crestal bone loss of 0.6–0.9 mm occurred around the implant. The smooth polished collar design of the implant may have contributed to crestal bone loss.  相似文献   
50.
Recent experiments on monoaminergic neurons have shown that neurotransmission can originate from somatic release. However, little is known about the quantity of monoamine available to be released through this extrasynaptic pathway or about the intracellular dynamics that mediate such release. Using three-photon microscopy, we directly imaged serotonin autofluorescence and investigated the total serotonin content, release competence, and release kinetics of somatic serotonergic vesicles in the dorsal raphe neurons of the rat. We found that the somata of primary cultured neurons contain a large number of serotonin-filled vesicles arranged in a perinuclear fashion. A similar distribution is also observed in fresh tissue slice preparations obtained from the rat dorsal raphe. We estimate that the soma of a cultured neuron on an average contains about 9 fmoles of serotonin in about 450 vesicles (or vesicle clusters) of < or =370 nm average diameter. A substantial fraction (>30%) of this serotonin is released with a time scale of several minutes by K(+)-induced depolarization or by para-chloroamphetamine treatment. The amount of releasable serotonin stored in the somatic vesicles is comparable to the total serotonin content of all the synaptic vesicles in a raphe neuron, indicating that somatic release can potentially play a major role in serotonergic neurotransmission in the mammalian brain.  相似文献   
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