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41.
The use of 19F spectroscopy and diffusion-weighted MRI to evaluate differences in gene-dependent enzyme prodrug therapies. 总被引:4,自引:0,他引:4
Daniel A Hamstra Kuei C Lee Joseph M Tychewicz Victor D Schepkin Bradford A Moffat Mark Chen Kenneth J Dornfeld Theodore S Lawrence Thomas L Chenevert Brian D Ross Juri T Gelovani Alnawaz Rehemtulla 《Molecular therapy》2004,10(5):916-928
To evaluate noninvasive measures of gene expression and tumor response in a gene-dependent enzyme prodrug therapy (GDEPT), a bifunctional fusion gene between Saccharomyces cerevisiae cytosine deaminase (CD) and Haemophilus influenzae uracil phosphoribosyltransferase (UPRT) was constructed. CD deaminates 5-fluorocytosine (5FC) to 5-fluorouracil (5FU), and UPRT subsequently converts 5FU to fluorouridine monophosphate, and both of these reactions can be monitored noninvasively in vitro and in vivo using 19F magnetic resonance spectroscopy (MRS). Following transient transfection the CD-UPRT fusion protein exhibited both UPRT and CD enzymatic activities as documented by 19F MRS. In addition, an increase in CD activity and thermal stability was witnessed for the fusion protein compared to native CD. Stable expression of CD-UPRT in 9L glioma cells increased both 5FC and 5FU sensitivity in vitro compared to CD-expressing and wild-type 9L cells. Noninvasive 19F MRS of both CD and UPRT gene function in vivo demonstrated that in animals bearing CD-expressing tumors there was limited conversion of 5FC to 5FU with no measurable accumulation of cytotoxic fluorinated nucleotides (F-nucs). In contrast, CD-UPRT-expressing tumors had increased CD gene activity with a threefold higher intratumoral accumulation of 5FU and significant generation of F-nucs. Finally, CD-UPRT yielded increased efficacy in an orthotopic animal model of high-grade glioma. More importantly, early changes in cellular water mobility, which are felt to reflect cellular death, as measured by diffusion-weighted MRI, were predictive of both durable response and increased animal survival. These results demonstrate the increased efficacy of the CD-UPRT GDEPT compared to CD alone both biochemically and in a preclinical model and validate both 19F MRS and diffusion-weighted MRI as tools to assess gene function and therapeutic efficacy. 相似文献
42.
Presented in this report is a modified arthroscopic approach to acromioclavicular joint reconstruction via suture and allograft fixation. An arthroscopic approach is used to expose the base of the coracoid by use of electrocautery. After an open distal clavicle excision is performed, clavicular and coracoid tunnels are created under arthroscopic visualization as previously described by Wolf and Pennington. The myotendinous end of a semitendinosus allograft is sutured to a Spider plate (Kinetikos Medical, San Diego, CA). The tendinous end of the graft is prepared with a running baseball stitch. A Nitinol wire with a loop end (Arthrex, Naples, FL) is used to pass 2 free FiberTape sutures (Arthrex) and the leading sutures from the tendinous end of the graft through the clavicular and coracoid tunnels, exiting out the anterior portal. One of the FiberTape sutures is retrieved with a grasper and passed over the anterior aspect of the distal clavicle. The second FiberTape suture and the allograft are passed over the distal end of the resected clavicle. While the acromioclavicular joint is held reduced, the FiberTape sutures are tied to the plate and the allograft is tensioned medially until the plate is embedded against the superior surface of the clavicle. The tendinous end of the graft is secured to the superior surface of the clavicle with a Bio-tenodesis screw (Arthrex) medial to the clavicular tunnel. 相似文献
43.
Berman Brian MD PhD Flores Javier MD † Pariser David MD ‡ Pariser Robert MD ‡ Araujo Tami de MD Ramirez Claudia C. MD 《Dermatologic surgery》2005,31(2):135-138
BACKGROUND Dermatologic procedures often cause some degree of pain. A self-warming patch containing lidocaine and tetracaine (L/T) was developed to provide topical local anesthesia prior to painful procedures.
OBJECTIVES To evaluate the safety and efficacy of a self-warming L/T patch to provide anesthesia in adult patients undergoing minor dermatologic procedures.
METHODS An active or placebo study drug was placed on adults 30 minutes prior to minor dermatologic surgical procedures in a prospectively randomized, double-blinded manner. Subcutaneous lidocaine injection was available during the procedure as a rescue medication if requested by the subject. Immediately following the procedure, the subjects, the investigator, and an independent observer rated pain intensity and adverse events were recorded.
RESULTS Patient-reported pain intensity was significantly lower in the L/T patch group ( p < .001 ). Investigators and an independent observer rated the pain in the L/T patch group to be less than in the placebo patch group ( p = .004 and p < .001 , respectively). Forty-nine percent of patients in the placebo group required rescue subcutaneous lidocaine compared with 22% in the L/T patch study group ( p = .008 ). One patient in the L/T patch group reported a transient moderate burning sensation.
CONCLUSION The self-warming L/T patch was effective in providing clinically useful local anesthesia for minor dermatologic procedures in adult patients.
ZARS, INC., PROVIDED SUPPORT VIA A SPONSORED RESEARCH GRANT TO THE UNIVERSITY OF MIAMI. 相似文献
OBJECTIVES To evaluate the safety and efficacy of a self-warming L/T patch to provide anesthesia in adult patients undergoing minor dermatologic procedures.
METHODS An active or placebo study drug was placed on adults 30 minutes prior to minor dermatologic surgical procedures in a prospectively randomized, double-blinded manner. Subcutaneous lidocaine injection was available during the procedure as a rescue medication if requested by the subject. Immediately following the procedure, the subjects, the investigator, and an independent observer rated pain intensity and adverse events were recorded.
RESULTS Patient-reported pain intensity was significantly lower in the L/T patch group ( p < .001 ). Investigators and an independent observer rated the pain in the L/T patch group to be less than in the placebo patch group ( p = .004 and p < .001 , respectively). Forty-nine percent of patients in the placebo group required rescue subcutaneous lidocaine compared with 22% in the L/T patch study group ( p = .008 ). One patient in the L/T patch group reported a transient moderate burning sensation.
CONCLUSION The self-warming L/T patch was effective in providing clinically useful local anesthesia for minor dermatologic procedures in adult patients.
ZARS, INC., PROVIDED SUPPORT VIA A SPONSORED RESEARCH GRANT TO THE UNIVERSITY OF MIAMI. 相似文献
44.
Noah Simmons Ognjen Brborovic Tozija Fimka Brian D Robie David L Bull Mome Spasovski Edward L Baker 《JPHMP》2005,11(4):351-356
The political disintegration of former Yugoslavia inaugurated in 1991 resulted in the decentralization of health systems in the federation's successor nation-states. Efforts by the Open Society Institute improved public health planning and management needs consequent to health sector changes. Beginning in Croatia in 2001, the Institute developed ongoing collaborations between Andrija Stampar School of Public Health and the US Centers for Disease Control and Prevention. In 2003 and 2004, it expanded its project to include the republics of Macedonia and of Serbia and Montenegro. 相似文献
45.
Five strains of infectious bronchitis virus isolated from commercial chickens from the state of Pennsylvania, USA during the years 1998 and 1999 were studied. The strains were selected for cross-challenge in specific pathogen free chickens and virus neutralization in chick embryos on the basis of partial S1 sequence amino acid identity values. The partial sequences analysed spanned the hypervariable amino terminus region of S1 from amino acid residues 48 to 219, based on the Beaudette strain. Using their S1 identity values, the strains represented a continuum of genetic, and thus antigenic, relationships. When compared with strain PA/5083/99, strain PA/Wolgemuth/98 had high sequence identity (96%) followed by PA/171/99 (85%), PA/5344/98 (70%) and PA/1220/98 (34%). The method of Archetti and Horsfall was used for calculating antigenic relatedness values of virus neutralization tests. The same formula was also applied to the percentage protection values of cross-challenge tests to derive protective relatedness values among the strains. The antigenic relatedness values, protective relatedness values, and the partial S1 sequence identity values were then analysed. The findings indicated partial S1 sequence identity values were more strongly correlated with protective relatedness values and than antigenic relatedness values. 相似文献
47.
OBJECTIVES: Radiopacity is a desirable property for most intra-oral materials. There are established ISO and ANSI/ADA protocols for determining radiopacity using film-based radiography. However, these methods are not always followed by researchers. This study aims to adapt those procedures by using digital radiography, a simplified stepwedge, and examine the effects of target distance and exposure time choice. METHODS: One millimetre thick samples of three dental materials were prepared by placing the materials into a 1.00 mm thick washer sandwiched between two glass slides. The samples were digitally radiographed alongside a stepwedge of aluminum alloy 1100 with an X-ray unit at 70 kVp using five different target distance/exposure time combinations. For each combination, the grey scale values of various thicknesses of the stepwedge were converted into absorbencies and plotted against their thickness. These plots were then linearly regressed in order to correlate absorbance with a thickness of aluminum for each target distance/exposure time combination. The absorbencies of each sample were then converted into radiopacities using these correlations. RESULTS: The correlations between the absorbance of the stepwedge and its thickness were highly linear. This linearity allows the correlation to be accurately deduced from fewer data points than required by the ISO and ANSI/ADA protocols. Varying exposure time did not significantly affect the mean radiopacity measured at a target distance of 30 cm. Varying the target distance did not significantly affect the measured radiopacity as long as the samples were properly exposed. SIGNIFICANCE: A simplified, consistent digital method for determining radiopacity is presented. 相似文献
48.
49.
Shook B. A. Wells M. J. Rapini R. P. Cohos E. 《世界核心医学期刊文摘》2006,2(8):41-41
作者报道2例确诊的慢性丙肝病毒感染患者合并获得性大疱性表皮松解症(EBA)。两例患者临床上均表现为典型EBA,包括皮肤脆性增加及自发和继发于外伤后发生皮肤水疱,继而以粟丘疹和瘢痕愈合。EBA常常是一种免疫状态改变或低下的疾病。还需进一步研究在这两例患者中和一般情况下丙肝病毒是否诱发EBA。 相似文献
50.
The aim of the present study was to determine whether patients with bronchiectasis and nontuberculous mycobacteria (NTM) have a higher prevalence of Aspergillus-related lung disease. A series of 30 consecutive patients with bronchiectasis and NTM (cases) were compared with 61 patients with bronchiectasis and no evidence of NTM (controls). Aspergillus serology and computerised tomography of the thorax were used to identify Aspergillus-related lung diseases, including aspergilloma, allergic bronchopulmonary aspergillosis and chronic necrotising pulmonary aspergillosis. The rate of positive Aspergillus serology was higher in cases with NTM disease compared with controls (10 out of 30 versus six out of 61). The radiological features of Aspergillus-related lung disease were also more common among patients with NTM disease than controls (six out of 30 versus none out of 61). This association between NTM disease and Aspergillus-related lung disease remained significant after adjustment for confounding effects of age and lung function (adjusted odds ratio 5.1, 95% confidence interval 1.5-17.0). Patients with bronchiectasis and nontuberculous mycobacterial disease have a higher prevalence of coexisting Aspergillus-related lung disease than patients with bronchiectasis and without nontuberculous mycobacteria. Identification of Aspergillus-related lung disease is important as prognosis amongst undetected cases is invariably poor. 相似文献