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1.
Based on its proven anabolic effects on bone in osteoporosis patients, recombinant parathyroid hormone (PTH1-34) has been evaluated as a potential therapy for skeletal repair. In animals, the effect of PTH1-34 has been investigated in various skeletal repair models such as fractures, allografting, spinal arthrodesis and distraction
osteogenesis. These studies have demonstrated that intermittent PTH1-34 treatment enhances and accelerates the skeletal repair process via a number of mechanisms, which include effects on mesenchymal
stem cells, angiogenesis, chondrogenesis, bone formation and resorption. Furthermore, PTH1-34 has been shown to enhance bone repair in challenged animal models of aging, inflammatory arthritis and glucocorticoid-induced
bone loss. This pre-clinical success has led to off-label clinical use and a number of case reports documenting PTH1-34 treatment of delayed-unions and non-unions have been published. Although a recently completed phase 2 clinical trial of PTH1-34 treatment of patients with radius fracture has failed to achieve its primary outcome, largely because of effective healing
in the placebo group, several secondary outcomes are statistically significant, highlighting important issues concerning the
appropriate patient population for PTH1-34 therapy in skeletal repair. Here, we review our current knowledge of the effects of PTH1-34 therapy for bone healing, enumerate several critical unresolved issues (e.g., appropriate dosing regimen and indications)
and discuss the long-term potential of this drug as an adjuvant for endogenous tissue engineering. 相似文献
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Edward Harrison 《BMJ (Clinical research ed.)》1916,1(2888):645-647
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Transcriptional regulatory network triggered by oxidative signals configures the early response mechanisms of japonica rice to chilling stress 总被引:3,自引:0,他引:3
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J.M.M. AdamsA.B. Ross K. AnastasakisE.M. Hodgson J.A. GallagherJ.M. Jones I.S. Donnison 《Bioresource technology》2011,102(1):226-234
To avoid negative impacts on food production, novel non-food biofuel feedstocks need to be identified and utilised. One option is to utilise marine biomass, notably fast-growing, large marine ‘plants’ such as the macroalgal kelps. This paper reports on the changing composition of Laminaria digitata throughout it growth cycle as determined by new technologies. The potential of Laminaria sp. as a feedstock for biofuel production and future biorefining possibilities was assessed through proximate and ultimate analysis, initial pyrolysis rates using thermo-gravimetric analysis (TGA), metals content and pyrolysis gas chromatography-mass spectrometry.Samples harvested in March contained the lowest proportion of carbohydrate and the highest ash and alkali metal content, whereas samples harvested in July contained the highest proportions of carbohydrate, lowest alkali metals and ash content. July was therefore considered the most suitable month for harvesting kelp biomass for thermochemical conversion to biofuels. 相似文献
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Ralf Heinrich Peter Bräunig Ismeni Walter Henning Schneider Edward A. Kravitz 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2000,186(7-8):617-629
In the American lobster (Homarus americanus) the biogenic amines serotonin and octopamine appear to play important and opposite roles in the regulation of aggressive behavior, in the establishment and/or maintenance of dominant and subordinate behavioral states and in the modulation of the associated postural stances and escape responses. The octopamine-containing neurosecretory neurons in the thoracic regions of the lobster ventral nerve cord fall into two morphological subgroups, the root octopamine cells, a classical neurohemal group with release regions along second thoracic roots, and the claw octopamine cells, a group that selectively innervates the claws. Cells of both subgroups have additional sets of endings within neuropil regions of ganglia of the ventral nerve cord. Octopamine neurosecretory neurons generally are silent, but when spontaneously active or when activated, they show large overshooting action potentials with prominent after-hyperpolarizations. Autoinhibition after high-frequency firing, which is also seen in other crustacean neurosecretory cells, is readily apparent in these cells. The cells show no spontaneous synaptic activity, but appear to be excited by a unitary source. Stimulation of lateral or medial giant axons, which excite serotonergic cells yielded no response in octopaminergic neurosecretory cells and no evidence for direct interactions between pairs of octopamine neurons, or between the octopaminergic and the serotonergic sets of neurosecretory neurons was found. 相似文献
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