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排序方式: 共有391条查询结果,搜索用时 15 毫秒
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
2.
Chantal Jeanne Beauchamp William Scott Chilton Patrice Dion Hani Antoun 《Applied microbiology》1990,56(1):150-155
This study was conducted to determine the capacities of 37 fungi to utilize various crown gall opines as their sole carbon and nitrogen source. One strain of Fusarium solani, two of Cylindrocarpon destructans, and six of Cylindrocarpon heteronema catabolized octopine, mannopine, octopinic acid, succinamopine, or a combination of these opines. One C. heteronema and one Fusarium dimerum strain grew only on succinamopine. None of the fungal isolates had the ability to grow on nopaline. The catabolism of opines by fungi was confirmed by the disappearance of the opine from the growth medium and by an increase in final mycelial dry weight with rising initial concentration of test substrate. This study thus shows that the catabolism of opines is not restricted to bacteria. 相似文献
3.
Litwin SB Mitra SK Von Colditz R Colditz JV Hamilton LB McManus T Jume'an HG Lazerson J 《Cardiovascular diseases》1981,8(3):364-371
The use of a fixed dosage schedule was compared with the use of activated clotting time (ACT) for determining heparin and protamine dosages during and after cardiopulmonary bypass disease. Use of the ACT resulted in a statistically significant increase in heparin dosage and a statistically significant reduction of postoperative blood loss. With ACT use, chest tubes were retained for a shorter period of time, and the incidence of serious postoperative hemorrhage was reduced from 44% to 18%. These results confirm the superiority of the ACT method for monitoring intraoperative anticoagulation in pediatric patients with congenital heart disease. 相似文献
4.
It is of an interest to document the molecular docking analysis of fluoroquinolones and other natural and synthetic compounds with the HCV NS3 helicase. Data shows that three fluoroquinolones interacted with the NS3 helicase in the catalytic region, targeting some of the amino acids known to play a crucial role in NS3 helicase activity. Similarly, binding energy shows that the fluoroquinolones were comparable to the thiazolpiperazinyl derivatives, while superior to several of the synthetic and natural derivatives. The results show three fluoroquinolones to be potent helicase inhibitors that can be repurposed as supplemental therapy against HCV especially in cases non-responsive to DAAAs. 相似文献
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Siti-Nazrina Camalxaman Nazariah Allaudin Zeenathul Yi-Wan Quah Hwei-San Loh Hassan Zuridah Homayoun Hani Abdul Rahman Sheikh-Omar Mohd Lila Mohd-Azmi 《In vitro cellular & developmental biology. Animal》2013,49(3):238-244
Endothelial cells have been implicated as key cells in promoting the pathogenesis and spread of cytomegalovirus (CMV) infection. This study describes the isolation and culture of rat brain endothelial cells (RBEC) and further evaluates the infectious potential of a Malaysian rat CMV (RCMV ALL-03) in these cultured cells. Brain tissues were mechanically fragmented, exposed to enzymatic digestion, purified by gradient density centrifugation, and cultured in vitro. Morphological characteristics and expression of von Willebrand factor (factor VIII-related antigen) verified the cells were of endothelial origin. RBEC were found to be permissive to the virus by cytopathic effects with detectable plaques formed within 7 d of infection. This was confirmed by electron microscopy examination which proved the existence of the viral particles in the infected cells. The susceptibility of the virus to these target cells under the experimental conditions described in this report provides a platform for developing a cell-culture-based experimental model for studies of RCMV pathogenesis and allows stimulation of further studies on host cell responses imposed by congenital viral infections. 相似文献
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Muhammad S. Nadeem Mohammed Razeeth Hani M. Z. Choudhry Firoz Anwar Mazin A. Zamzami Bibi N. Murtaza Fahad A. M. Al-Abbasi Mohammad I. Khan Abdul R. Shakoori 《Journal of cellular biochemistry》2020,121(1):125-134
Escherichia coli is frequently exploited for genetic manipulations and heterologous gene expression studies. We have evaluated the metabolic profile of E. coli strain BL21 (DE3) RIL CodonPlus after genetic modifications and subjecting to the production of recombinant protein. Three genetically variable E. coli cell types were studied, normal cells (susceptible to antibiotics) cultured in simple LB medium, cells harboring ampicillin-resistant plasmid pET21a (+), grown under antibiotic stress, and cells having recombinant plasmid pET21a (+) ligated with bacterial lactate dehydrogenase gene grown under ampicillin and standard isopropyl thiogalactoside (IPTG)-induced gene expression conditions. A total of 592 metabolites were identified through liquid chromatography-mass spectrometry/mass spectrometry analysis, feature and peak detection using XCMS and CAMERA followed by precursor identification by METLIN-based procedures. Overall, 107 metabolites were found differentially regulated among genetically modified cells. Quantitative analysis has shown a significant modulation in DHNA-CoA, p-aminobenzoic acid, and citrulline levels, indicating an alteration in vitamin K, folic acid biosynthesis, and urea cycle of E. coli cells during heterologous gene expression. Modulations in energy metabolites including NADH, AMP, ADP, ATP, carbohydrate, terpenoids, fatty acid metabolites, diadenosine tetraphosphate (Ap4A), and l -carnitine advocate major metabolic rearrangements. Our study provides a broader insight into the metabolic adaptations of bacterial cells during gene manipulation experiments that can be prolonged to improve the yield of heterologous gene products and concomitant production of valuable biomolecules. 相似文献
10.
Hani A. Gomaa 《Archives Of Phytopathology And Plant Protection》2013,46(11):1081-1087
Egg masses laid by Spodoptera littoralis mated female moths were extracted by petroleum ether (PE), ethanol (E) and Ringer's solution (RS). Egg-wash extracts were evaporated and the weights of crude materials were obtained. Different aqueous concentrations were made. The amount of extracted material increased as the weight of eggs used increased and vice versa. Coating Nerium oleander leaves with aqueous egg-wash extracts prepared from S. littoralis egg-masses deterred the mated conspecific female moths from ovipositing their eggs on treated leaves, as well as causing a decrease in the total number of deposited eggs per female during the moth's life span. The highest deterrent effect on conspecific female moths to oviposit their eggs was obtained after treatment of N. oleander leaves with PE or E egg-wash extract. The deterrent effects of the tested egg-wash extracts was concentration dependant; an increase in the concentration of any extract caused an obvious decrease in the number of deposited egg-masses and the total number of laid eggs on the treated N. oleander leaves. 相似文献