Purpose: Recently, dose calculations using mega‐voltage cone beam CT (MVCBCT) images have been reported. The dose volume histograms of the dose plan using MVCBCT images have been already compared to ...those of kilo‐voltage CT (kVCT) for clinical cases. In the reposts, comparisons of the plan dose were made, however, experimental dose verification has not performed yet. In this report, we experimentally evaluated the usefulness of the dose calculation using MVCBCT images. Method and Materials: First, we corrected the uniformity of CT number on MVCBCT images. Next, dose verification was performed in a homogeneous PMMA phantom. Dose at multiple points were calculated using corrected MVCBCT images and kVCT images. Then, the calculated dose was evaluated with a MOSFET detector. Finally, we performed similar dose verifications in an anthropomorphic phantom. To consider the positional accuracy and precision of the detector in the phantom, another series of measurement was repeatedly performed 3 times. Results: The relative dose differences between the calculated dose and the measured dose were obtained up to 3.2 % for both images in the PMMA phantom. The dose differences for corrected MVCBCT images agreed with those for the kVCT images within 1 %. Therefore, we confirmed the usefulness of proposed uniformity correction for MVCBCT images. On the other hand, for dose verifications in the anthropomorphic phantom, the average of the dose differences was 5.2 % for the corrected MVCBCT images and 4.3 % for the kVCT images. We can explain the differences by measurement error and setup error of the MOSFET detector. Reproducibility was up to 1.4 % among the series of measurement using the detector. Conclusion: The dose calculations using the corrected MVCBCT images agreed well with those using the kVCT images in the anthropomorphic phantom. We will apply the dose calculation using MVCBCT images to clinical situation.
In the current studies, we deposited ultra-thin hydroxyapatite films on a pure titanium substrate by pulsed laser deposition, and we examined the effects of these surfaces on rat bone marrow (RBM) ...cells. This method allowed deposition of 500-, 2000-, and 5000-Angstrom-thick hydroxyapatite films. X-ray diffraction showed that the amorphous films recrystallized to a hydroxyapatite crystal structure after annealing. The proliferation of RBM cells was unaffected by the hydroxyapatite films, but osteocalsin and alkaline phosphatase mRNA and protein levels were elevated in cells grown on 2000- and 5000-Angstrom-thick films. These results indicate that ultra-thin hydroxyapatite films generated by pulsed laser deposition are better at promoting osteogenesis than pure titanium surfaces.
We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sNN=200 GeV. The charged hadron is ...measured at midrapidity |eta|<0.35, and the energy is measured at large rapidity (-3.7<eta< -3.1, Au-going direction). An enhanced near-side angular correlation across | Delta eta|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v2 for inclusive charged hadrons at midrapidity up to pT=4.5 GeV/c. We also present the measurement of v2 for identified pi+ or - and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sNN=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.
Post-translational modification of histone N-tails affects eukaryotic gene activity. In Arabidopsis, the histone modification level correlates with gene activation and repression in vernalization and ...flowering processes, but there is little information on changes in histone modification status and nucleosome structure under abiotic stresses. We determined the temporal and spatial changes in nucleosome occupancy and levels of H3K4me3, H3K9ac, H3K14ac, H3K23ac and H3K27ac in the histone H3 N-tail on the regions of four Arabidopsis drought stress-inducible genes, RD29A, RD29B, RD20 and RAP2.4, under drought stress conditions by chromatin immunoprecipitation analysis. We found two types of regulatory mechanisms of nucleosome occupancy function in the drought stress response. For RD29A and RD29B genes, nucleosome occupancy of promoter regions is low compared with that of coding regions, and no notable nucleosome loss occurs under drought stress. In contrast, nucleosome density is gradually decreased in response to drought stress on RD20 and RAP2.4 genes. Enrichments of H3K4me3 and H3K9ac correlate with gene activation in response to drought stress in all four genes. Interestingly, establishment of H3K4me3 occurs after accumulation of RNAPII on the coding regions of RD29A and RAP2.4. Enrichment of H3K23ac and H3K27ac occurs in response to drought stress on the coding regions of RD29B, RD20 and RAP2.4, but not on the coding region of RD29A. Our results indicate that histone modifications on the H3 N-tail are altered with gene activation on the coding regions of drought stress-responsive genes under drought stress conditions and that several patterns of nucleosome changes function in the drought stress response.
Summary
Background Retinoids and active vitamin D3 analogues regulate the proliferation and differentiation of keratinocytes and are effective in the treatment of psoriasis. Retinoids are known to ...be effective against acne vulgaris through comedolysis. However, the comedolytic effect of active vitamin D3 analogues has not been reported.
Objectives To investigate whether maxacalcitol, one of the active vitamin D3 analogues, has a comedolytic effect by using spontaneously comedogenic rhino mice.
Methods Rhino mice were treated topically with tretinoin and maxacalcitol once daily for 2 and 4 weeks, respectively. The dermal side of the epidermal sheet was observed to determine the size of the utricle. Haematoxylin and eosin‐stained vertical sections were used to measure utricle diameter and density and to evaluate histological changes.
Results Maxacalcitol (25 μg g−1) and tretinoin (0·1%) significantly decreased the size and the diameter of the utricle after 1 week of treatment. However, maxacalcitol did not affect the density while tretinoin did have an effect. Histopathologically, maxacalcitol and tretinoin markedly induced epidermal hyperplasia accompanied by a minor accumulation of inflammatory cells in the dermis, with and without hypercornification, respectively.
Conclusions These results indicate that maxacalcitol has a prominent effect on comedolysis and that its mechanism of action may be different from that of retinoids.
To evaluate the effect of eyelid hygiene after cataract surgery on eyelid and ocular surface findings, subjective symptoms and visual function, including functional visual acuity (FVA) and higher ...order aberration, in a randomized controlled study.
Fifty patients who underwent cataract surgery at a single institution were involved. Twenty-five patients were instructed to wipe their eyelids twice a day from one to four weeks postoperatively, whereas the other 25 patients did not perform any eyelid hygiene. Optical measurement, FVA, meibomian glands, the grade of meibum, lid margin findings, fluorescein corneal staining findings, dry eye-related subjective symptoms and surgical satisfaction were assessed both preoperatively and one month postoperatively.
In the eyelid hygiene group, the visual maintenance ratio of FVA improved significantly (p = 0.048) and the higher order aberration of the 4th + 6th order deteriorated less (p = 0.027) compared with the control group. Multiple regression analyses showed that the change in visual maintenance ratio was associated with surgical satisfaction (p = 0.003), change in corneal staining score (p = 0.007), history of eye diseases (p = 0.029) and eyelid hygiene (p = 0.048).
Eyelid hygiene after cataract surgery may be effective for visual function measured with an FVA test.
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