Enhancement of gene transduction efficiency in cancer cells using cationic liposome with hyperthermia.

We evaluated the effects of hyperthermia on the efficiency of gene transduction by using a cationic liposome to develop an efficient method for lipofection. We used Lewis lung carcinoma (LLC), NIH3T3, and A549 cell lines, with Lipofectamine reagent as the cationic liposome and the LacZ gene as the reporter gene. In LLC, co-incubation of the cationic liposome and plasmid DNA complex (lipoplex) with the cells for 2 h at 41 degrees C enhanced the efficiency of gene transduction approximately 1.4-fold compared to incubation for 2 h at 37 degrees C, as measured by X-gal staining and beta-galactosidase activity. In cell lines NIH3T3 and A549, the efficiency of gene transduction showed a tendency toward enhancement after 2 h co-incubation with lipoplex at 41 degrees C compared to that at 37 degrees C, as measured by X-gal staining. This is the first study to demonstrate the enhancement of gene transduction efficiency achieved by using a cationic liposome under conditions of hyperthermia. This method should prove useful for lipofection in other cancer cells.</p

Real-world management of treatment-naïve diabetic macular oedema : 2-year visual outcome focusing on the starting year of intervention from STREAT-DMO study

Background/aims To investigate the yearly change of real-world outcomes for best corrected visual acuity (BCVA) after 2-year clinical intervention for treatment-naïve diabetic macular oedema (DMO). Methods Retrospective analysis of aggregated, longitudinal medical records obtained from 27 retina specialised institutions in Japan from Survey of Treatment for DMO database. A total of 2049 treatment-naïve centre involving DMO eyes of which the initial intervention started between 2010 and 2015, and had been followed for 2 years, were eligible. As interventions, antivascular endothelial growth factor (VEGF) agents, local corticosteroids, macular photocoagulation and vitrectomy were defined. In each eye, baseline and final BCVA, the number of each intervention for 2 years was extracted. Each eye was classified by starting year of interventional treatment. Results Although baseline BCVA did not change by year, 2-year improvement of BCVA had been increased, and reached to +6.5 letters in the latest term. There is little difference among starting year about proportions of eyes which BCVA gained >15 letters, in contrast to those which lost >15 letters were decreased by year. The proportion of eyes receiving anti-VEGF therapy was dramatically increased, while those receiving the other therapies were gradually decreased. The proportion of eyes which maintained socially good vision of BCVA>20/40 has been increased and reached to 59.0% in the latest term. Conclusion For recent years, treatment patterns for DMO have been gradually but certainly changed; as a result, better visual gain, suppression of worsened eyes and better final BCVA have been obtained. Anti-VEGF therapy has become the first-line therapy and its injection frequency has been increasing

Real-world management of treatment-naïve diabetic macular oedema in Japan : two-year visual outcomes with and without anti-VEGF therapy in the STREAT-DME study

Background/Aims To investigate real-world outcomes for best-corrected visual acuity (BCVA) after 2-year clinical intervention for treatment-naïve, centr-involving diabetic macular oedema (DME). Methods Retrospective analysis of longitudinal medical records obtained from 27 institutions specialising in retinal diseases in Japan. A total of 2049 eyes with treatment-naïve DME commencing intervention between 2010 and 2015 who were followed for 2 years were eligible. Interventions for DME included anti-vascular endothelial growth factor (VEGF) therapy, local corticosteroid therapy, macular photocoagulation and vitrectomy. Baseline and final BCVA (logMAR) were assessed. Eyes were classified by the treatment pattern, depending on whether anti-VEGF therapy was used, into an anti-VEGF monotherapy group (group A), a combination therapy group (group B) and a group without anti-VEGF therapy (group C). Results The mean 2-year improvement of BCVA was −0.04±0.40 and final BCVA of >20/40 was obtained in 46.3% of eyes. Based on the treatment pattern, there were 427 eyes (20.9%) in group A, 807 eyes (39.4%) in group B and 815 eyes (39.8%) in group C. Mean improvement of BCVA was −0.09±0.39, –0.02±0.40 and −0.05±0.39, and the percentage of eyes with final BCVA of >20/40 was 49.4%, 38.9%, and 52.0%, respectively. Conclusion Following 2-year real-world management of treatment-naïve DME in Japan, BCVA improved by 2 letters. Eyes treated by anti-VEGF monotherapy showed a better visual prognosis than eyes receiving combination therapy. Despite treatment for DME being selected by specialists in consideration of medical and social factors, a satisfactory visual prognosis was not obtained, but final BCVA remained >20/40 in half of all eyes

A Simple Method for MR Elastography: A Gradient-Echo Type Multi-Echo Sequence

To demonstrate the feasibility of a novel MR elastography (MRE) technique based on a conventional gradient-echo type multi-echo MR sequence which does not need additional bipolar magnetic field gradients (motion encoding gradient: MEG), yet is sensitive to vibration. In a gradient-echo type multi-echo MR sequence, several images are produced from each echo of the train with different echo times (TEs). If these echoes are synchronized with the vibration, each readout\u27s gradient lobes achieve a MEG-like effect, and the later generated echo causes a greater MEG-like effect. The sequence was tested for the tissue-mimicking agarose gel phantoms and the psoas major muscles of healthy volunteers. It was confirmed that the readout gradient lobes caused an MEG-like effect and the later TE images had higher sensitivity to vibrations. The magnitude image of later generated echo suffered the T2 decay and the susceptibility artifacts, but the wave image and elastogram of later generated echo were unaffected by these effects. In in vivo experiments, this method was able to measure the mean shear modulus of the psoas major muscle. From the results of phantom experiments and volunteer studies, it was shown that this method has clinical application potential

Magnetic Resonance Elastography using an air ball-actuator

The purpose of this study was to develop a new technique for a powerful compact MR Elastography (MRE) actuator based on a pneumatic ball-vibrator. This is a compact actuator that generates powerful centrifugal force vibrations via high speed revolutions of an internal ball using compressed air. This equipment is easy to handle due to its simple principles and structure. Vibration frequency and centrifugal force are freely adjustable via air pressure changes (air flow volume), and replacement of the internal ball. In order to achieve MRI compatibility, all parts were constructed from non-ferromagnetic materials. Vibration amplitudes (displacements) were measured optically by a laser displacement sensor. From a bench test of displacement, even though the vibration frequency increased, the amount of displacement did not decrease. An essential step in MRE is the generationof mechanical waves within tissue via an actuator, and MRE sequences are synchronized to several phase offsets of vibration. In this system, the phase offset was detected by a four-channel optical-fiber sensor, and it was used as an MRI trigger signal. In an agarose gel phantom experiment, this actuator was used to make an MR elastogram. This study shows that the use of a ball actuator for MRE is feasible