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91.
PURPOSE: Bioluminescent imaging permits sensitive in vivo detection and quantification of cells engineered to emit light. We developed a bioluminescent human renal cancer cell line for in vitro and in vivo studies. MATERIAL AND METHODS: The 2 human renal cell carcinoma cell lines SN12-C and SN12-L1 were stably transfected to constitutively express luciferase using a retroviral shuttle. The bioluminescent signal was correlated with tumor cell numbers in vitro. Parental and transfected cells were compared by growth kinetics and histology. Tumor burden after heterotopic injection in immune deficient mice was monitored up to 39 days. The kinetics of the bioluminescent signal was evaluated for 1 to 60 minutes following luciferin injection. RESULTS: Bioengineered renal cancer cell lines stably expressed luciferase. The growth kinetics of the cells in vitro and the histology of tumors resulting from implantation of these cells were unaffected by retroviral transfection with the luciferase gene. As few as 1,000 cells could be reliably detected. The intensity of the bioluminescent signal correlated with the number of tumor cells in vitro. Photon emission in vivo and ex vivo correlated significantly with tumor weight at sacrifice. After intraperitoneal injection of luciferin there was a time dependent change in the intensity of the bioluminescent signal with maximum photon emission at 20 minutes (optimal 17 to 25). CONCLUSIONS: Luciferase transfected human renal cancer lines allow reliable, rapid, noninvasive and longitudinal monitoring of tumor growth in vivo. The ability to assess tumor development in vivo with time is economical and effective compared to end point data experiments.  相似文献   
92.
Heart complications are among the serious problems of patients with β-thalassemia intermedia. This study aimed to evaluate myocardial function in these patients. Clinical parameters and both standard Doppler and pulsed Doppler tissue imaging parameters were compared in 51 β-thalassemia intermedia patients (mean age, 17.05 ± 5.8 years) and 20 normal subjects (mean age, 17.81 ± 7.35 years, p = 0.98). In 11 patients (21.5%), pulmonary artery hypertension was detected. M-mode echocardiographic findings such as ejection fraction and fractional shortening did not show statistically significant changes (p > 0.005). Pulsed Doppler showed a significant difference in the early (E) to late diastolic (A) velocity ratio of the tricuspid and mitral valve between the patients and the control subjects (p < 0.05). In the pulsed tissue Doppler study, the peak systolic velocity of the septum (Ss), the peak atrial velocity of the septum (Aas), the peak systolic velocity of the tricuspid annulus (St), the peak early diastolic velocity of the tricuspid annulus (Eat), and the peak late diastolic velocity of the tricuspid annulus (Aat) were increased significantly (p < 0.05). The pulse tissue Doppler of the lateral mitral annulus did not change significantly (p > 0.005). The peak systolic velocity of the posterior wall and the peak late diastolic velocity of the anterior wall changed significantly (p < 0.05). This study showed that β-thalassemia intermedia patients with normal M-mode and two-dimensional echocardiography had statistically significant changes in pulsed Doppler and pulsed tissue Doppler imaging.  相似文献   
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International Ophthalmology - To evaluate the outcomes and complications of simultaneous silicon oil removal (SOR) and phacoemulsification and intra ocular lens implantation. In this retrospective...  相似文献   
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Cigarette smoke is the major risk factor for the development of chronic obstructive pulmonary disease (COPD). Macrophages are suggested to orchestrate the chronic inflammatory response and tissue destruction associated with COPD by secreting interleukin (IL)-8, a major neutrophil chemoattractant. The combination of inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists are increasingly used as maintenance therapy in patients with COPD. The aim of this study was to determine whether combined fluticasone propionate, a corticosteroid, and salmeterol, a long-acting beta(2)-adrenoceptor agonist, can suppress IL-8 production by human macrophages. To mimic resident macrophages in the lung, human monocytes were cultured for 5 days in medium containing Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) and Macrophage Colony Stimulating Factor (M-CSF). In human Monocyte-Derived Macrophages, we found that cigarette smoke medium strongly enhanced IL-8 release in a time- and concentration-dependent manner. IL-8 release by cigarette smoke was significantly suppressed in a concentration-dependent manner by fluticasone and salmeterol. Coincubation of the drugs potentiated the inhibitory effect on cigarette smoke medium-induced IL-8 production and longer preincubation times resulted in more IL-8 inhibition. Interestingly, preincubation of cells with suboptimal concentration of salmeterol for 4 h before fluticasone administration for 30 min potentiates the inhibitory effect of fluticasone on IL-8 release. In conclusion, combination therapy may provide benefits over monotherapy for the treatment of COPD patients.  相似文献   
96.
Various molecular methods have been used for the rapid identification of mycobacterial species. In this survey, evaluation of antibiotic resistance and PCR-restriction fragment length polymorphism analysis (PRA) of the hsp65 gene was carried out for identification of non-tuberculosis mycobacteria (NTM) isolates from different clinical specimens. Forty-eight different mycobacterial isolates were selected and followed by the conventional and PRA of hsp65 for species identification. The antibiotic susceptibility test was carried out according to standard methods. A 439 bp PCR product of hsp65 in all selected isolates was amplified and digested with the BstEII and HaeIII restriction enzymes. The restriction fragment length polymorphism (RFLP) patterns were analyzed for species identification. Using PRA for 48 mycobacterial selected isolates, including 15 M. tuberculosis, one M. bovis and all 32 isolates of NTM, revealed 11 different species among the NTM isolates. The most frequent NTM isolates were M. kansasii, M. gordonae III, M. marinum, M. chelonae, M. scrofluaceum and M. gastri. In most cases, the PRA results were perfectly in accordance with the classical biochemical method. Combination of resistance to rifampin and isoniazid was present among M. kansasi, M. gordoniae III, M. scrofluaceum, M. chelonae, M. marinum, M. gastri, M. gordoniae II and M. trivale isolates. A high incidence of co-resistance to six, five, four and three anti-TB drugs was observed in 18.5%, 9.1%, 6.6% and 11.7% of all NTM isolates, respectively. Our results showed that PRA, in comparison with classical methods, is rapid and accurate enough for the identification of mycobacterial species from LJ medium. Additionally, we found that in Iran we have a highly diverse population of NTM isolates among patients suspected of having TB.  相似文献   
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Interactive, mobile, AGIle and novel education (IMAGINE) is a conceptual framework to help students with disabilities (SwD) participate more in the physical space and become more engaged in school. IMAGINE recommends and reminds students, and allows them to make requests of key learning resources (LRs). The goal of IMAGINE is to provide SwD with the location and time for attending a LR that is most optimal with respect to their learning style and preference, learning performance and other activities. IMAGINE will be a means through which SWD will be provided with tailored recommendations with respect to their daily activities to improve learning outcomes. A pilot was conducted with SwD who used IMAGINE’s navigation and wayfinding functionality, and the subjects reported that it aligns well with their needs. Preliminary results suggest that after completing a training and using the tool, SwD reported that they are more likely to use the tool and their participation may increase as a result. In contrast to before the trial, the SwD were also able to better describe the tool’s benefits and how to improve its functionality after using the tool for four weeks.
  • Implications for Rehabilitation
  • The IMAGINE tool may be a means through which SwD can be provided with tailored recommendations with respect to their daily activities to improve learning outcomes.

  • PWD should be involved (as research study participants and research study team members) in the design and development of tools like IMAGINE to improve participation.

  • IMAGINE and similar tools may not only encourage better learning outcomes, but also more physical participation in the community, and could be used across education and employment settings.

  相似文献   
100.
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