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91.
After spinal cord injury (SCI), a complex cascade of events leads to tissue degeneration and a penumbra of cell death. Neuroprotective molecules to limit tissue loss are promising; however, intravenous delivery is limited by the blood-spinal cord barrier and short systemic half-life. Current local delivery strategies are flawed: bolus injection results in drug dispersion throughout the intrathecal (IT) space, and catheters/pumps are invasive and open to infection. Our laboratory previously developed a hydrogel of hyaluronan (HA) and methylcellulose (MC) (HAMC) that, when injected into the IT space, was safe and, remarkably, had some therapeutic benefit on its own. In order to test this new paradigm of local and sustained delivery, relative to conventional delivery strategies, we tested, for the first time, the in vivo efficacy of HAMC as an IT drug delivery system by delivering a known neuroprotective molecule, erythropoietin (EPO). In vitro studies showed that EPO was released from HAMC within 16 h, with 80% bioactivity maintained. When the material alone was injected in vivo, individual fluorescent labels on HA and MC showed that HA dissolved from the gel within 24 h, whereas the hydrophobically associated MC persisted in the IT space for 4-7 days. Using a clip compression injury model of moderate severity, HAMC with EPO was injected in the IT space and, in order to better understand the potential of this delivery system, compared to the therapeutic effect of both common delivery strategies-IT EPO and intraperitoneal EPO-and a control of IT HAMC alone. IT HAMC delivery of EPO resulted in both reduced cavitation after SCI and a greater number of neurons relative to the other delivery strategies. These data suggest that the localized and sustained release of EPO at the tissue site by HAMC delivery enhances neuroprotection. This new system of IT delivery holds great promise for the safe, efficacious, and local delivery of therapeutic molecules directly to the spinal cord. 相似文献
92.
93.
Yip Ronald ML Cheung Tommy T So Ho Chan Julia PS Ho Carmen TK Tsang Helen HL Yu Carrel KL Wong Priscilla CH 《Clinical rheumatology》2023,42(8):2013-2027
Clinical Rheumatology - Gout is one of the most common noncommunicable diseases in Hong Kong. Although effective treatment options are readily available, the management of gout in Hong Kong remains... 相似文献
94.
D Pathirana A Nast AD Ormerod N Reytan P Saiag CH Smith P Spuls B Rzany 《Journal of the European Academy of Dermatology and Venereology》2010,24(12):1458-1467
Background The development of evidence based guidelines is a demanding and time consuming process. Therefore it is important to share the knowledge and discuss the structure of these guidelines in detail. Objectives To present a method report on the development process of the European evidence based guidelines on the systemic treatment of psoriasis vulgaris with the aim to offer guidance to other guidelines groups with lesser experience and to critically appraise the methodology of the guidelines development process. Methods The guidelines are based on the previously evaluated literature from three European national evidence based guidelines and an additional systematic search and evaluation of new literature. Further steps included a structured consensus conference and a DELPHI procedure to develop the recommendations, as well as several internal and external reviews. All steps were coordinated by the Division of evidence based medicine in cooperation with a group of methodologists. Results A total of 114 studies were included, serving as base for the efficacy chapters of the intervention. The recommendations, based on the efficacy and the level of evidence of the included studies were discussed and finally consented by the guidelines group. After subsequent reviews the guidelines were presented to the European Dermatology Forum, European Academy of Dermatology and Venereology and Union Européenne des Médicins Spécialistes for approval and published in October 2009. Conclusion The development of European evidence based guidelines requires a coordinated structure which can be achieved by the integration of an experienced group of methodologists. Nevertheless further improvements are imaginable and might be considered for an update or other European evidence based guidelines. 相似文献
95.
96.
AIM: The aim of the present in-vitro study was to combine directly the Canal Leader handpiece (SET, Olching, Germany) with the electronic apex locators ROOT ZX (Morita, Kyoto, Japan) and JUSTY (Yoshida, Tokyo, Japan) to find out whether the working length values thus obtained were identical to those resulting from the combination of the same electronic devices with hand files. METHODOLOGY: A total of 50 natural extracted teeth with single canals and mature apices were used. A radiograph was used as a control and the distance from the radiographic apex to the tip of the file was measured and compared with the results of the electronic length determination. RESULTS: For both electronic devices the differences amongst the distribution of the measurements were not statistically significant under the specified conditions (P > 0.05), indicating that the measurements with hand files and with the Canal Leader were identical for the majority of the cases. CONCLUSIONS: Under the conditions of this study the working length of canals obtained with electronically assisted hand files were similar to those obtained with the electronically assisted mechanical handpiece Canal Leader. 相似文献
97.
Nimodipine, a calcium channel blocker, is known to increase cerebral blood flow. In the present study, the authors investigated the effect of nimodipine on spinal cord blood flow in normal rats. Cardiovascular parameters, including mean systemic arterial blood pressure, cardiac output, and heart rate, were recorded during infusion of nimodipine in a dose-response fashion. The experiment was a randomized blind study in which four groups of five rats received different doses of nimodipine (0.001, 0.01, 0.05, and 0.10 mg/kg) intravenously over 30 minutes, and a control group of five rats received only the diluent. The hydrogen clearance and thermodilution techniques were used to measure spinal cord blood flow and cardiac output, respectively. The 0.05-mg/kg dose of nimodipine caused the largest increase in spinal cord blood flow, with a 40% increase over the preinfusion level, although there was a 25% reduction in mean arterial pressure. The 0.10-mg/kg dose did not increase spinal cord blood flow more than the 0.05-mg/kg dose, most likely due to the concomitant 37% reduction in mean arterial pressure. Cardiac output was significantly increased by the 0.05- and 0.10-mg/kg doses secondary to the drop in total peripheral resistance. The increase in spinal cord blood flow produced by nimodipine lasted approximately 20 minutes after the termination of the infusion. Thus, nimodipine at a dose of 0.05 mg/kg markedly increased blood flow in the normal spinal cord even though there were major changes in mean systemic arterial pressure and cardiac output. Further research is required to determine whether this drug might be beneficial in treating ischemic states of the spinal cord, such as posttraumatic ischemia. 相似文献
98.
目的 探讨延续性护理在心脏瓣膜置换术患者中的应用效果.方法 选取2017年1月—2019年1月在四川省德阳市人民医院接受心脏瓣膜置换术治疗的80例瓣膜性心脏病患者作为研究对象,随机分为观察组和对照组各40例.出院后对照组不进行主动护理,观察组采用延续性护理,对两组患者干预前后服药依从性、生活质量及心功能进行比较分析.结果 出院时两组服药依从性、生活质量及心功能比较差异无统计学意义(P>0.05),出院后6个月观察组服药依从性、生活质量及心功能均优于对照组,差异有统计学意义(P<0.05).结论 延续性护理应用于心脏瓣膜置换术出院患者中可提高患者服药依从性,提升患者生活质量及心功能恢复,值得临床借鉴推广. 相似文献
99.
To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants.
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
Methodology:
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
Results:
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
Conclusions:
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
100.
S. F. Varavi M.D. D.C.H. J. R. Kamat MD. D.CH M. K. Joshi M.D. D.C.H. Dr. P. W. Kandoth M.D. D.C.H. 《Indian journal of pediatrics》1982,49(5):665-669
Immunoglobulins were estimated in the cerebrospinal fluid from 70 cases of nervous system diseases. Thirty childern with evidence of C.N.S. irritation without infection served as controls. The immunoglobulins were higher in cases with C.N. S infections. Within this group meningeal involvement (tubercular and pyogenic) resulted in a significant rise in IgG compared to viral encephalitis. The proportion of immunoglobulin in the CSF protein can be helpful in distinguishing TBM from PM. 相似文献