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The aim of this study was to evaluate the effects of combining a porous poly(L-lactide-co-epsilon-caprolactone)/beta-tricalcium phosphate membrane and gelatin sponge incorporating basic fibroblastic growth factor (bFGF) on bone regeneration in mandibular ridges. Four full-thickness saddle-type defects (10 mm long x 5 mm deep) were symmetrically created in both edentulous mandibular alveolar ridges of 6 beagles. The dome-shaped membrane was secured to each defect site, and a gelatin sponge containing 200 microg bFGF was implanted on the left side of each defect (experimental group). Only the membranes (control group) were secured to the defect sites on the right. Three and 6 months later, 3 animals were killed. Bone regeneration was analyzed by soft X-ray photographs, micro-computed tomography (CT) images, and peripheral quantitative CT (pQCT), and then examined histologically. Soft X-ray examination revealed an increase in new bone volume in the experimental group 6 months postoperatively. pQCT showed that immature bone density was higher in the experimental group. Micro-CT images revealed well formed new bone along the original contour of the dome-shaped membrane in the experimental group. Histologically, inflammatory infiltration of tissue surrounding the membranes was slight. These results suggest that combining the poly(L-lactide-co-epsilon-caprolactone)/beta-tricalcium phosphate membrane and bFGF-gelatin sponge is promising for alveolar ridge reconstruction.  相似文献   
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VEGF-B primarily provides neuroprotection and improves survival in CNS-derived neurons. However, its actions on the peripheral nervous system have been less characterized. We examined whether VEGF-B mediates peripheral nerve repair. We found that VEGF-B induced extensive neurite growth and branching in trigeminal ganglia neurons in a manner that required selective activation of transmembrane receptors and was distinct from VEGF-A–induced neuronal growth. VEGF-B–induced neurite elongation required PI3K and Notch signaling. In vivo, VEGF-B is required for normal nerve regeneration: mice lacking VEGF-B showed impaired nerve repair with concomitant impaired trophic function. VEGF-B treatment increased nerve regeneration, sensation recovery, and trophic functions of injured corneal peripheral nerves in VEGF-B–deficient and wild-type animals, without affecting uninjured nerves. These selective effects of VEGF-B on injured nerves and its lack of angiogenic activity makes VEGF-B a suitable therapeutic target to treat nerve injury.Nerves can be damaged either through trauma or disease. Nerves from the peripheral nervous system (PNS) have significantly greater capacity to regenerate and reinnervate their original targets after injury, compared with nerves from the CNS. The successful regeneration of PNS neurons requires a number of intrinsic and extrinsic factors, as well as a permissive microenvironment for axonal regrowth (1). Among the numerous growth factors able to induce nerve regeneration, the family of VEGFs has been implicated as a potent mediator of developmental neurogenesis and adult nerve regeneration (24). VEGF-A is a well-characterized and potent angiogenic factor but is also a strong inducer of nerve growth. Several studies have demonstrated that both VEGF-A and -B are expressed during peripheral nerve injury (2, 5). In the setting of injury, VEGF-B plays a role in cell survival, nerve protection, and growth (5, 6). The survival effect of VEGF-B on brain cortical neurons, retinal neurons, and motor neurons in the spinal cord is indicative of its pleiotropic role (5). VEGF-B treatment reduced stroke volume in a middle cerebral artery ligation model and increased survival of retinal ganglion cells in an optic nerve crush injury model (7), and VEGF-B knockout mice suffered severe strokes and exacerbated retinal ganglion cell death in both injury models (79). VEGF-B has also been used with promising results in Parkinson’s disease (10) and amyotrophic lateral sclerosis models (11).Given the ability of VEGF-B to regulate both vascular endothelial cells (angiogenesis) as well as axonal growth and survival after injury, it is unclear whether VEGF-B exerts its effects on nerve regeneration through the increase in blood supply or through direct effects on nerve tissue. Indeed, specific studies on its role on peripheral neurons independent of its vascular role are lacking. We have previously reported that VEGF-A can stimulate trigeminal neuronal cell growth and enhance cornea nerve regeneration, resulting in anatomical and functional recovery of peripheral injured nerves independently of its angiogenic effects (12). Here we studied the neuro-regenerative potential of VEGF-B in an avascular model of peripheral nerve injury in mice and the signaling elements involved in the induction of nerve growth. Our results demonstrated tha (i) peripheral nerve regeneration is impaired in mice lacking VEGF-B, (ii) VEGF-B can restore the anatomic and function innervation of target tissues by induction of nerve growth and nerve regeneration, (iii) the effects of VEGF-B are specific for injured nerves and are independent of any vascular effect, and (iv) the effects of VEGF-B on nerve regeneration are distinct from those observed for VEGF-A.  相似文献   
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The efficacy of CS-834, a novel oral carbapenem, was assessed by using a murine model of pneumonia caused by penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae and was compared with those of oral cephems, i.e., cefteram pivoxil, cefpodoxime proxetil, cefdinir, and cefditoren pivoxil. Intranasal inoculation of 106 CFU of penicillin-susceptible or penicillin-resistant S. pneumoniae in the exponential growth phase induced pneumonia and bacteremia in ddY mice within 48 h. For the treatment of infections caused by the penicillin-susceptible strain the antibiotics were administered orally at 0.4, 2, and 10 mg/kg of body weight twice daily for 2 days beginning at 24 h after bacterial inoculation, and for the treatment of infections caused by a penicillin-resistant strain the antibiotics were administered at 2, 10, and 50 mg/kg twice daily for 2 days beginning at 24 h after bacterial inoculation. Among the antibiotics tested, CS-834 exhibited the most potent efficacy against both types of strains. Against infections caused by penicillin-susceptible S. pneumoniae, CS-834 at all doses significantly reduced the numbers of viable cells in both the lungs and blood. Cefpodoxime proxetil at all doses and cefteram pivoxil and cefditoren pivoxil at doses of 2 and 10 mg/kg showed comparable efficacies. Against infections caused by penicillin-resistant S. pneumoniae, CS-834 at doses of 10 and 50 mg/kg showed the most potent efficacy among the antibiotics tested, resulting in the maximum decrease in the numbers of viable cells in the lungs. Comparable efficacies were observed with cefteram pivoxil and cefpodoxime proxetil at doses of 50 mg/kg each. The concentration of CS-834 in the lungs and blood was higher than that of cefdinir and was lower than those of the other antibiotics tested, suggesting that the potent therapeutic efficacy of CS-834 reflects its strong activity against S. pneumoniae.  相似文献   
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The most frequent and representative nephrotic syndrome associated with collagen disease is encountered in patients suffering from lupus nephritis. Lupus nephritis is a glomerulonephritis, which discloses various localizations of immune complexes in the endothelium, mesangium and subepithelium. In addition, vasculitides complicated by nephrotic syndrome also show the deposition of immune complexes in their glomeruli, such as Henoch-Sch?nlein nephritis and cryoglobulinemic nephritis. The pathogenetic mechanisms of these nephrotic syndromes are explained as follows. The depositions of immune complexes in glomeruli causes proteinuria through a variety of mechanisms. Namely, subendothelial and mesangial immune deposits give capillary and mesangial injuries as well as inflammation that are mediated through activation of complements and cytokines, and subsequently leads to nephrotic-range proteinuria and impairment of renal function. On the other hand, subepithelial and intramembranous deposits disrupt the regulated arrangement of epithelial cells and slit diaphragms, and then disturb the slit diaphragms. The eventual dysfunction of slit diaphragms accordingly progresses to massive proteinuria even without capillary injury. Therefore, nephrotic syndrome associated with collagen disease or vasculitis is usually observed in lupus nephritis or vasculitis related to immune complex depositions, but is not observed in non-immune complex glomerulopathy or vasculopathy.  相似文献   
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Proinflammatory agents trypsin and mast cell tryptase cleave and activate PAR2, which is expressed on sensory nerves to cause neurogenic inflammation. Transient receptor potential A1 (TRPA1) is an excitatory ion channel on primary sensory nerves of pain pathway. Here, we show that a functional interaction of PAR2 and TRPA1 in dorsal root ganglion (DRG) neurons could contribute to the sensation of inflammatory pain. Frequent colocalization of TRPA1 with PAR2 was found in rat DRG neurons. PAR2 activation increased the TRPA1 currents evoked by its agonists in HEK293 cells transfected with TRPA1, as well as DRG neurons. Application of phospholipase C (PLC) inhibitors or phosphatidylinositol-4,5-bisphosphate (PIP(2)) suppressed this potentiation. Decrease of plasma membrane PIP(2) levels through antibody sequestration or PLC-mediated hydrolysis mimicked the potentiating effects of PAR2 activation at the cellular level. Thus, the increased TRPA1 sensitivity may have been due to activation of PLC, which releases the inhibition of TRPA1 from plasma membrane PIP(2). These results identify for the first time to our knowledge a sensitization mechanism of TRPA1 and a novel mechanism through which trypsin or tryptase released in response to tissue inflammation might trigger the sensation of pain by TRPA1 activation.  相似文献   
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A 12-week pilot controlled trial of a physical activity (PA) buddy program was designed for women with young children. Conducted in January 2015 through March 2016, 49 women (mean age = 36.4 ± 4.8 years) were randomized to one of two groups. Both conditions received an in-person session, weekly step goals based on their baseline number of steps, an accelerometer, and its mobile app. Only women assigned to the intervention group brought their buddies and exercised together at least once per week. Buddies also received an accelerometer and its mobile app. Among 47 women who completed the study, we found no significant difference between groups in changes in the mean number of daily steps for the prior week (p = 0.56). When women were categorized into three groups based on change in buddies’ PA, those with inactive buddies had significantly less change in number of steps than those with an active buddy and those in the control group (p < 0.018). Those with an active buddy also had higher friend social support scores for PA than the other two groups (= 0.05). Thus, to improve PA, creating a social environment in which women associate with active individuals may be necessary.  相似文献   
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