Effects of Cold Stimulation on Mitochondrial Activity and VEGF Expression in vitro

We aimed to clarify the effects of cold stimulation at various temperatures on mitochondrial activity and vascular endothelial growth factor (VEGF) expression in vitro. Human fibroblast, human mesenchymal stem cell, and rat skeletal muscle myoblast cell lines were used. For each cell type, cells were divided into 4 groups and stimulated in various cold temperatures (0, 4, 17 and 25°C) 3 times for 15 min each by placement on crushed ice or floating on cold water set at each temperature. Control cells were subjected to warm water at 37°C. Factors related to mitochondrial activity, mitochondrial DNA copy numbers, and VEGF expression were analyzed 24 h after the last cold stimulation. In all cell types, significant increases of factors related to mitochondrial activity and mitochondrial DNA copy numbers were seen in the 4°C and 17°C-stimulated cells compared with control cells. In rat skeletal muscle cells stimulated at 4°C, VEGF expression significantly increased compared to the control cells. Our data suggest that cold stimulation at certain temperatures promotes mitochondrial activity, biogenesis and VEGF expression.

Pedometer-Based Behavioral Change Program Can Improve Dependency in Sedentary Older Adults: A Randomized Controlled Trial

BACKGROUND

Recent studies suggested that pedometer-based walking programs are applicable to older adults.

OBJECTIVES

The purpose of this study was to evaluate the use of pedometer in sedentary older adults to improve physical activity, fear of falling, physical performance, and leg muscle mass.

DESIGN

This was a pilot randomized controlled trial (RCT).

SETTING AND PARTICIPANTS

Eighty-seven community dwelling sedentary older adults living in Japan.

INTERVENTION

The intervention group (n=43) received a pedometer-based behavioural change program for 6 months, while the control group (n=44) did not. The participants in the intervention group were instructed to increase their mean daily steps by 10% each month. Thus, at the end of 6 months, participants in the intervention group were expected to have 77 % more daily steps than their baseline step counts. Written activity logs were monthly averaged to determine whether the participants were achieving their goal.

MEASUREMENTS

Outcome measures were physical activity, fear of falling, physical performances, and leg muscle mass.

RESULTS

In this 6-month trial 40 older adults (93%) completed the pedometer protocol with good adherence. In the intervention group, average daily steps were increased by 83.4% (from 20311323 to 3726 1607) during the study period, but not in the control group (from 20471698 to 22671837). The pedometer-based behavioral change program was more effective to improve their physical activity, fear of falling, locomotive function, and leg muscle mass than control (P<0.05).

CONCLUSION

These results suggested that the pedometer-based behavioral change program can effectively improve the physical activity, fear of falling, physical performance, and leg muscle mass in sedentary older adults.

Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses

It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.

Multi-site Study of Diffusion Metric Variability: Characterizing the Effects of Site, Vendor, Field Strength, and Echo Time using the Histogram Distance

MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.

C5-azobenzene-functionalized locked nucleic acid uridine: isomerization properties, hybridization ability, and enzymatic stability

Oligonucleotides (ONs) modified with a locked nucleic acid (LNA) are widely used in the fields of therapeutics, diagnosis, and nanotechnology. There have been significant efforts towards developing LNA analogues bearing modified bridges to improve their hybridization ability, nuclease resistance, and pharmacokinetic profiles. Moreover, nucleobase modifications of LNA are useful strategies for the functionalization of ONs. Modifications of the C5-position of pyrimidine nucleobases are particularly interesting because they enable predictable positioning of functional groups in the major groove of the duplex. Here we report the synthesis of C5-azobenzene-functionalized LNA uridine (LNA-U(Az)) and properties of LNA-U(Az)-modified ONs, including isomerization properties, hybridization ability, and enzyme stability. LNA-U(Az) in ON is photo-isomerized effectively and reversibly by irradiation at 365 nm (trans to cis) and 450 nm (cis to trans). LNA-U(Az)-modified ONs show RNA-selective hybridization ability despite the large hydrophobic azobenzene moiety extending into the major groove of the duplex. The enzymatic stability of LNA-U(Az)-modified ONs is higher than that of natural and LNA-modified ONs with or without photo-irradiation. Our results indicate that LNA-U(Az) holds promise for RNA targeting and photo-switchable technologies.

Variation in patient position and impact on carbon-ion scanning beam distribution during prostate treatment

OBJECTIVE

We assessed the impact of changes in patient position on carbon-ion scanning beam distribution during treatment for prostate cancer.

METHODS

68 patients were selected. Carbon-ion scanning dose was calculated. Two different planning target volumes (PTVs) were defined: PTV1 was the clinical target volume plus a set-up margin for the anterior/lateral sides and posterior side, while PTV2 was the same as PTV1 minus the posterior side. Total prescribed doses of 34.4 Gy [relative biological effectiveness (RBE)] and 17.2 Gy (RBE) were given to PTV1 and PTV2, respectively. To estimate the influence of geometric variations on dose distribution, the dose was recalculated on the rigidly shifted single planning CT based on two dimensional-three dimensional rigid registration of the orthogonal radiographs before and after treatment for the fraction of maximum positional changes.

RESULTS

Intrafractional patient positional change values averaged over all patients throughout the treatment course were less than the target registration error = 2.00 mm and angular error = 1.27°. However, these maximum positional errors did not occur in all 12 treatment fractions. Even though large positional changes occurred during irradiation in all treatment fractions, lowest dose encompassing 95% of the target (D95)-PTV1 was >98% of the prescribed dose.

CONCLUSION

Intrafractional patient positional changes occurred during treatment beam irradiation and degraded carbon-ion beam dose distribution. Our evaluation did not consider non-rigid deformations, however, dose distribution was still within clinically acceptable levels.

ADVANCES IN KNOWLEDGE

Inter- and intrafractional changes did not affect carbon-ion beam prostate treatment accuracy.

Epithelial-mesenchymal status renders differential responses to cisplatin in ovarian cancer

Chemoresistance to platinums, such as cisplatin, is of critical concern in the treatment of ovarian cancer. Recent evidence has linked epithelial-mesenchymal transition (EMT) as a contributing mechanism. The current study explored the connection between cellular responses to cisplatin and EMT in ovarian cancer. Expression microarrays were utilized to estimate the EMT status as a binary phenotype, and the transcriptional responses of 46 ovarian cancer cell lines to cisplatin were measured at dosages equivalent to 50% growth inhibition. Phenotypic responses to cisplatin were quantified with respect to cell number, proliferation rate and apoptosis, and then compared with the epithelial or mesenchymal status. Ovarian cancer cell lines with an epithelial status exhibited higher resistance to cisplatin treatment in the MTS assay than those with a mesenchymal status. Pathway analyses revealed the induction of G1/S- and S-phase genes (P=0.001) and the activation of multiple NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) downstream genes (P=0.0016) by cisplatin selectively in epithelial-like cell lines. BrdU incorporation and Caspase-3/7 release assays confirmed impaired apoptosis in epithelial-like ovarian cancer cells. In clinical samples, we observed resistance to single platinum treatment and the selective activation of the NF-κB pathway by platinum in ovarian cancers with an epithelial status. Overall, our results suggest that, in epithelial-like ovarian cancer cells, NF-κB activation by cisplatin may lead to defective apoptosis, preferential proliferation arrest and a consequential decreased sensitivity to cisplatin.

Impact of treatment planning with deformable image registration on dose distribution for carbon-ion beam lung treatment using a fixed irradiation port and rotating couch

OBJECTIVE

When using a fixed irradiation port, treatment couch rotation is necessary to increase beam angle selection. We evaluated dose variations associated with positional morphological changes to organs.

METHODS

We retrospectively chose the data sets of ten patients with lung cancer who underwent respiratory-gated CT at three different couch rotation angles (0°, 20° and -20°). The respective CT data sets are referred to as CT0, CT20 and CT-20. Three treatment plans were generated as follows: in Plan 1, all compensating bolus designs and dose distributions were calculated using CT0. To evaluate the rotation effect without considering morphology changes, in Plan 2, the compensating boli designed using CT0 were applied to the CT±20 images. Plan 3 involved compensating boli designed using the CT±20 images. The accumulated dose distributions were calculated using deformable image registration (DIR).

RESULTS

A sufficient prescribed dose was calculated for the planning target volume (PTV) in Plan 1 [minimum dose received by a volume ≥95% (D95) > 95.8%]. By contrast, Plan 2 showed degraded dose conformation to the PTV (D95 > 90%) owing to mismatch of the bolus design to the morphological positional changes in the respective CT. The dose assessment results of Plan 3 were very close to those of Plan 1.

CONCLUSION

Dose distribution is significantly affected by whether or not positional organ morphology changes are factored into dose planning.

ADVANCES IN KNOWLEDGE

In treatment planning using multiple CT scans with different couch positions, it is mandatory to calculate the accumulated dose using DIR.

Effect of secondary particles on image quality of dynamic flat panels in carbon ion scanning beam treatment

OBJECTIVE

Real-time markerless tumour tracking using radiographic fluoroscopic imaging is one of the better solutions to improving respiratory-gated radiotherapy. However, particle beams cause secondary particles from patients, which could affect radiographs. Here, we evaluated the quality of radiographs during carbon ion pencil beam scanning (CPBS) irradiation for respiratory gating.

METHODS

A water phantom and chest phantom were used. The phantoms were irradiated with CPBS at 290 MeV n(-1) from orthogonal directions. Dose rates were 3.4 × 10(8), 1.14 × 10(8) and 3.79 × 10(7) particles per second. A dynamic flat panel detector (DFPD) was installed on the upstream (DFPD1) or downstream (DFPD2) side of the vertical irradiation port. DFPD images were acquired during CPBS at 15.00, 7.50 and 3.75 frames per second (fps). Charge on the DFPD was cleaned using fast readout technique every 30 fps. DFPD images were acquired during CPBS with radiographic exposure, and results with and without fast readout technique were compared.

RESULTS

Secondary particles were visualized as spots or streak-like shapes. Capture of secondary particles from the horizontal beam direction was lower with fast readout technique than without it. With regard to beam irradiation direction dependency, CPBS from the horizontal direction resulted in a greater magnitude of secondary particles reaching DFPD2 than reaching DFPD1. When CPBS was delivered from the vertical direction, however, the magnitude of secondary particles on both DFPDs was very similar.

CONCLUSION

Fast readout technique minimized the effect of secondary particles on DFPD images during CPBS.

ADVANCES IN KNOWLEDGE

This technique may be useful for markerless tumour tracking for respiratory gating.

Implementation of a target volume design function for intrafractional range variation in a particle beam treatment planning system

OBJECTIVE

Treatment planning for charged particle therapy in the thoracic and abdominal regions should take account of range uncertainty due to intrafractional motion. Here, we developed a design tool (4Dtool) for the target volume [field-specific target volume (FTV)], which accounts for this uncertainty using four-dimensional CT (4DCT).

METHODS

Target and normal tissue contours were input manually into a treatment planning system (TPS). These data were transferred to the 4Dtool via the picture archiving and communication system (PACS). Contours at the reference phase were propagated to other phases by deformable image registration. FTV was calculated using 4DCT on the 4Dtool. The TPS displays FTV contours using digital imaging and communications in medicine files imported from the PACS. These treatment parameters on the CT image at the reference phase were then used for dose calculation on the TPS. The tool was tested in single clinical case randomly selected from patients treated at our centre for lung cancer.

RESULTS

In this clinical case, calculation of dose distribution with the 4Dtool resulted in the successful delivery of carbon-ion beam at the reference phase of 95% of the prescribed dose to the clinical target volume (CTV). Application to the other phases also provided sufficient dose to the CTV.

CONCLUSION

The 4Dtool software allows the design of the target volume with consideration to intrafractional range variation and is now in routine clinical use at our institution.

ADVANCES IN KNOWLEDGE

Our alternative technique represents a practical approach to four-dimensional treatment planning within the current state of charged particle therapy.

Macro- and microstructural changes in patients with spinocerebellar ataxia type 6: assessment of phylogenetic subdivisions of the cerebellum and the brain stem

BACKGROUND AND PURPOSE

Site-specific degeneration patterns of the infratentorial brain in relation to phylogenetic origins may relate to symptoms in patients with spinocerebellar degeneration, but the patterns are still unclear. We investigated macro- and microstructural changes of the infratentorial brain based on phylogenetic origins and their correlation with symptoms in patients with spinocerebellar ataxia type 6.

MATERIALS AND METHODS

MR images of 9 patients with spinocerebellar ataxia type 6 and 9 age- and sex-matched controls were obtained. We divided the infratentorial brain on the basis of phylogenetic origins and performed an atlas-based analysis. Comparisons of the 2 groups and a correlation analysis assessed with the International Cooperative Ataxia Rating Scale excluding age effects were performed.

RESULTS

A significant decrease of fractional volume and an increase of mean diffusivity were seen in all subdivisions of the cerebellum and in all the cerebellar peduncles except mean diffusivity in the inferior cerebellar peduncle in patients compared with controls (P < .0001 to <.05). The bilateral anterior lobes showed the strongest atrophy. Fractional volume decreased mainly in old regions, whereas mean diffusivity increased mainly in new regions of the cerebellum. Reflecting this tendency, the International Cooperative Ataxia Rating Scale total score showed strong correlations in fractional volume in the right flocculonodular lobe and the bilateral deep structures and in mean diffusivity in the bilateral posterior lobes (r = 0.73 to ±0.87).

CONCLUSIONS

We found characteristic macro- and microstructural changes, depending on phylogenetic regions of the infratentorial brain, that strongly correlated with clinical symptoms in patients with spinocerebellar ataxia type 6.

FZD7 drives in vitro aggressiveness in Stem-A subtype of ovarian cancer via regulation of non-canonical Wnt/PCP pathway

Ovarian cancer (OC) can be classified into five biologically distinct molecular subgroups: epithelial-A (Epi-A), Epi-B, mesenchymal (Mes), Stem-A and Stem-B. Among them, Stem-A expresses genes relating to stemness and is correlated with poor clinical prognosis. In this study, we show that frizzled family receptor 7 (FZD7), a receptor for Wnt signalling, is overexpressed in the Stem-A subgroup. To elucidate the functional roles of FZD7, we used an RNA interference gene knockdown approach in three Stem-A cell lines: CH1, PA1 and OV-17R. Si-FZD7 OC cells showed reduced cell proliferation with an increase in the G0/G1 sub-population, with no effect on apoptosis. The cells also displayed a distinctive morphologic change by colony compaction to become more epithelial-like and polarised with smaller internuclear distances and increased z-axis height. Immunofluorescence (IF) staining patterns of pan-cadherin and β-catenin suggested an increase in cadherin-based cell–cell adhesion in si-FZD7 cells. We also observed a significant rearrangement in the actin cytoskeleton and an increase in tensile contractility in si-FZD7 OC cells, as evident by the loss of stress fibres and the redistribution of phospho-myosin light chain (pMLC) from the sites of cell–cell contacts to the periphery of cell colonies. Furthermore, there was reciprocal regulation of RhoA (Ras homolog family member A) and Rac1 (Ras-related C3 botulinum toxin substrate 1 (Rho family, small GTP-binding protein Rac1)) activities upon FZD7 knockdown, with a significant reduction in RhoA activity and a concomitant upregulation in Rac1 activity. These changes in pMLC and RhoA, as well as the increased TopFlash reporter activities in si-FZD7 cells, suggested involvement of the non-canonical Wnt/planar cell polarity (PCP) pathway. Selected PCP pathway genes (cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3), prickle homolog 4 (Drosophila) (PRICKLE4), dishevelled-associated activator of morphogenesis 1 (DAAM1), profilin 2 (PFN2), protocadherin 9 (PCDH9), protocadherin α1 (PCDHA1), protocadherin β17 pseudogene (PCDHB17), protocadherin β3 (PCDHB3), sprouty homolog 1 (SPRY1) and protein tyrosine kinase 7 (PTK7)) were found to be more highly expressed in Stem-A than non Stem-A subgroup of OC. Taken together, our results suggest that FZD7 might drive aggressiveness in Stem-A OC by regulating cell proliferation, cell cycle progression, maintenance of the Mes phenotype and cell migration via casein kinase 1ɛ-mediated non-canonical Wnt/PCP pathway.

Expressions of local renin-angiotensin system components in chondrocytes

In 2013, we reported that local reninangiotensin system (local RAS) components express during the hypertrophic differentiation of chondrocytes and can modulate it, using ATDC5 cell line that involves differentiation from mesenchymal stem cells to calcified hypertrophic chondrocytes. However, the expressions of local RAS components in normal chondrocytes have not been revealed yet. The purpose of this study is to examine the expression of the local RAS components in chondrocytes in vivo and the conditions allowing the expression. We stained five major regions of 8-week-old C57BL/6 adult mice in which chondrocytes exist, including epiphyseal plates and hyaline cartilages, with antibodies to local RAS components. We also examined the expression of local RAS components in the cultured bovine’s articular cartilage chondrocytes using quantitative reverse transcription polymerase chain reaction and western blot analysis. In result, hypertrophic chondrocytes of epiphyseal plates included in the tibia and the lamina terminals expressed local RAS components. However, hyaline chondrocytes, including the knee articular cartilages, the parenchyma of nasal septums and of the tracheal walls, did not express local RAS components. Cultured bovine’s articular cartilage chondrocytes also did not express local RAS components. However, inducing hypertrophy by administering interleukin-1β or tumor necrosis factor-α, the cultured articular chondrocytes also expressed angiotensin II type 1 receptor and angiotensin II type 2 receptor. In conclusion, local RAS components express particularly in chondrocytes which occur hypertrophy and do not in hyaline chondrocytes. The results are in accord with our previous in vitro study. We think this novel knowledge is important to investigate cartilage hypertrophy and diseases induced by hypertrophic changes like osteoarthritis.

Real-time image-processing algorithm for markerless tumour tracking using X-ray fluoroscopic imaging

OBJECTIVE

To ensure accuracy in respiratory-gating treatment, X-ray fluoroscopic imaging is used to detect tumour position in real time. Detection accuracy is strongly dependent on image quality, particularly positional differences between the patient and treatment couch. We developed a new algorithm to improve the quality of images obtained in X-ray fluoroscopic imaging and report the preliminary results.

METHODS

Two oblique X-ray fluoroscopic images were acquired using a dynamic flat panel detector (DFPD) for two patients with lung cancer. The weighting factor was applied to the DFPD image in respective columns, because most anatomical structures, as well as the treatment couch and port cover edge, were aligned in the superior-inferior direction when the patient lay on the treatment couch. The weighting factors for the respective columns were varied until the standard deviation of the pixel values within the image region was minimized. Once the weighting factors were calculated, the quality of the DFPD image was improved by applying the factors to multiframe images.

RESULTS

Applying the image-processing algorithm produced substantial improvement in the quality of images, and the image contrast was increased. The treatment couch and irradiation port edge, which were not related to a patient's position, were removed. The average image-processing time was 1.1 ms, showing that this fast image processing can be applied to real-time tumour-tracking systems.

CONCLUSION

These findings indicate that this image-processing algorithm improves the image quality in patients with lung cancer and successfully removes objects not related to the patient.

ADVANCES IN KNOWLEDGE

Our image-processing algorithm might be useful in improving gated-treatment accuracy.