Architecture of the Medial Smooth Muscle of the Arterial Vessels in the Normal Human Brain: A Scanning Electron-Microscopic Study

The architecture of the medial smooth muscle of arterial vessels in normal human brains was investigated using scanning electron microscopy. We could divide the arterial vessels into four subdivisions according to the number of the circular muscle cells. The arteries ( \u3e 100 μm in diameter) had 4-20 layers of circular smooth muscle cells; individual circular muscle cells were spindle-shaped and occasionally had branches at their ends. Multidirectional muscle cells were observed in the medio-adventitial border only at the branching sites in large arteries (\u3e300 μm), but at both branching and non-branching sites in the small arteries (100-300 μm). The nonterminal arterioles (30-100 μm) had 2-3 layers of circular muscle cells; most of the circular muscle cells had nodular or rod-like processes at their branched ends. Multidirectional muscle cells were most frequently observed in the medio-adventitial border in this subdivision at both branching and non-branching sites. The terminal arterioles (10-30 μm) had a single layer of circular muscle cells. Multipolar (stellate in appearance) smooth muscle cells were mainly seen in the medio-adventitial border at branching sites. The precapillary arterioles (7-10 μm) had a single layer of branched muscle cells; individual muscle cells had 2-4 circular branches on both sides of the central bulges

Effect of eldecalcitol, an active vitamin D analog, on hip structure and biomechanical properties: 3D assessment by clinical CT.

The effects of an active vitamin D analog, eldecalcitol (ELD), on bone mineral density (BMD), bone geometry, and biomechanical properties of the proximal femur were investigated by using clinical CT. The subjects - a subgroup of a recent randomized, double-blind study comparing anti-fracture efficacy of ELD with alfacalcidol (ALF) - constituted 193 ambulatory patients with osteoporosis (189 postmenopausal women and 4 men aged 52-85years, average±SD: 70.9±6.92years) enrolled at 11 institutions. Multidetector-row CT data was acquired at baseline and at completion of 144weeks\u27 treatment. Cross-sectional densitometric and geometric parameters of the femoral neck were derived from three-dimensional CT data. Biomechanical properties including cross-sectional moment of inertia (CSMI), section modulus (SM) and buckling ratio (BR) of the femoral neck, and CSMI of the femoral shaft were also calculated. We found that, 1) with respect to the femoral neck cross-sectional parameters (total bone), in the ALF group, volumetric BMD (vBMD) decreased but bone mass was maintained and cross-sectional area (CSA) increased. In contrast, ELD maintained vBMD with a significant increase in bone mass and a trend toward increased CSA. 2) With respect to the femoral neck cross-sectional parameters (cortex), cortical thickness decreased in the ALF group, but was maintained in the ELD group. In the ALF group, vBMD and bone mass increased, and CSA was maintained. In the ELD group, vBMD, CSA, and bone mass increased. 3) With respect to the biomechanical properties of the femoral neck, ELD improved CSMI and SM to a greater extent than did ALF. BR increased in both the ALF and ELD groups. 4) With respect to the femoral shaft parameters, overall the results of bone geometry and CSMI of the femoral shaft were very consistent with the results for the femoral neck; however, cortical vBMD of the femoral shaft decreased significantly in both the ELD and ALF groups. In conclusion, our longitudinal analysis of hip geometry by clinical CT revealed the unexpected potential of ELD to increase cortical CSA, vBMD, and bone mass, and to maintain cortical thickness, probably through the more potent effect of ELD in mitigating endocortical bone resorption than ALF. By improving the biomechanical properties of the proximal femur, ELD may have the potential to reduce the risk of hip fractures

The Search for a Primordial Magnetic Field

Magnetic fields appear wherever plasma and currents can be found. As such, they thread through all scales in Nature. It is natural, therefore, to suppose that magnetic fields might have been formed within the high temperature environments of the big bang. Such a primordial magnetic field (PMF) would be expected to arise from and/or influence a variety of cosmological phenomena such as inflation, cosmic phase transitions, big bang nucleosynthesis, the cosmic microwave background (CMB) temperature and polarization anisotropies, the cosmic gravity wave background, and the formation of large-scale structure. In this review, we summarize the development of theoretical models for analyzing the observational consequences of a PMF. We also summarize the current state of the art in the search for observational evidence of a PMF. In particular we review the framework needed to calculate the effects of a PMF power spectrum on the CMB and the development of large scale structure. We summarize the current constraints on the PMF amplitude $B_\lambda$ and the power spectral index $n_B$ and discuss prospects for better determining these quantities in the near future.Comment: 40 pages, 13 figures, Accepted for Physics Reports 23 Feb 2012. Available online 3 March 2012. In press, corrected proo

Effects of a 1.5 T time-varying magnetic field on cell volume regulation of bovine adrenal chromaffin cells in hyposmotic media

Effects of a time-varying magnetic field on cell volume regulation by hyposmotic stress in cultured bovine adrenal chromaffin cells were examined. Through regulatory volume decrease (RVD), cell volume of chromaffin cells that were incubated in a hypotonic medium initially increased, reached a peak and finally recovered to the initial value. Two hour exposure to a magnetic field and addition of cytochalasin D increased peak value and delayed return to initial value. Intracellular F-actin contents initially decreased but returned to normal levels after 10 sec. Two hour exposure to the magnetic field and addition of cytochalasin D continuously reduced the F-actin content. Results suggest that exposure to the magnetic field stimulated disruption of the actin cytoskeleton and that the disruption delayed the recovery to the volume prior to osmotic stress

Molecular biomarkers in the context of focal therapy for prostate cancer: Recommendations of a delphi consensus from the focal therapy society

BACKGROUND: Focal therapy (FT) for prostate cancer (PCa) is promising. However, long-term oncological results are awaited and there is no consensus on follow-up strategies. Molecular biomarkers (MB) may be useful in selecting, treating and following up men undergoing FT, though there is limited evidence in this field to guide practice. We aimed to conduct a consensus meeting, endorsed by the Focal Therapy Society, amongst a large group of experts, to understand the potential utility of MB in FT for localized PCa. METHODS: A 38-item questionnaire was built following a literature search. The authors then performed three rounds of a Delphi Consensus using DelphiManager, using the GRADE grid scoring system, followed by a face-to-face expert meeting. Three areas of interest were identified and covered concerning MB for FT, 1) the current/present role; 2) the potential/future role; 3) the recommended features for future studies. Consensus was defined using a 70% agreement threshold. RESULTS: Of 95 invited experts, 42 (44.2%) completed the three Delphi rounds. Twenty-four items reached a consensus and they were then approved at the meeting involving (N.=15) experts. Fourteen items reached a consensus on uncertainty, or they did not reach a consensus. They were re-discussed, resulting in a consensus (N.=3), a consensus on a partial agreement (N.=1), and a consensus on uncertainty (N.=10). A final list of statements were derived from the approved and discussed items, with the addition of three generated statements, to provide guidance regarding MB in the context of FT for localized PCa. Research efforts in this field should be considered a priority. CONCLUSIONS: The present study detailed an initial consensus on the use of MB in FT for PCa. This is until evidence becomes available on the subject

A comparative study of PET images among different PET scanners for detection infinitesimal radioactivity

[Purpose]Detectingthe distribution of positron emitter generated by nuclear fragmentationreaction in carbon ion beam therapy (auto-activation) applied at Heavy IonMedical Accelerator in Chiba (HIMAC) by means of positron emission tomography(PET) is novel method for therapy quality assurance especially assessingirradiated area. In clinical auto-activation PET settings, we have experienceda significant difference of image quality between LSO-based PET system andBGO-based PET system. Therefore, we planned and performed some phantomexperiments to compare PET scanner performance to image infinitesimalradioactivity. [Methods]Four different PET scanners were used; EXACT HR+,Biograph 16 HiRez (CTI-Siemens), SET-3000 GX/T (Shimadzu corp.) and jPET D4which provides four-layer-depth-of-interaction (DOI) measurement. The crystaldetector materials of each PET scanner were as follows: BGO, LSO, GSO and GSOwith DOI, respectively. A phantom was filled with 18F solution, and scannedevery 6hr until its radioactivity was decayed to the level of the infinitesimalradioactivity generated in clinical auto-activation PET settings. After CT scanor transmission scan for attenuation correction, emission scan was acquired for40min in 3D mode. The emission images were reconstructed by either FBP or OSEM.Reconstructed images were evaluated by visually.[Result]Image quality of thephantom became worse according to the decay of 18F. In particular, imagequality degraded severely when scanned with LSO-based PET system compared tothe others. GSO-based PET system improved the image of infinitesimal radioactivitybetter compared to that of BGO-PET system, because sensitivity of GSO-based PETsystem was 2-fold-higher than BGO-based PET system. Additionally, jPET D4 whichwas one of GSO-based PET system performed best in image quality for 18F phantomstudy due to high sensitivity derived from DOI measurement. The randomcoincidence events of LSO-based PET system were 1M counts when itsradioactivity was almost equally to clinical auto-activation settings, whilethe true coincidence was 0.2M counts. The true/random ratio was 24.3%, bycontrast, that of other PET systems was 99.9%. The reason why serious imagedegradation occurred when scanned with LSO-based PET system might be due topresence of 176Lu in LSO crystals[Conclusion]According to analysis of coincidenceevents, LSO-based PET system was not suitable for detecting infinitesimalradioactivity due to intrinsic radioactivity of 176Lu. An evaluation of imagequality suggested that high sensitive PET system, like jPET D4, was necessaryto detect infinitesimal radioactivity. To image the auto-activation using PETscanner, we must take characteristics of crystals and sensitivity of PET systeminto consideration.EANM Annual Congress 201

Molecular biomarkers in the context of focal therapy for prostate cancer: recommendations of a Delphi Consensus from the Focal Therapy Society

BACKGROUND: Focal therapy (FT) for prostate cancer (PCa) is promising. However, long-term oncological results are awaited and there is no consensus on follow-up strategies. Molecular biomarkers (MB) may be useful in selecting, treating and following up men undergoing FT, though there is limited evidence in this field to guide practice. We aimed to conduct a consensus meeting, endorsed by the Focal Therapy Society, amongst a large group of experts, to understand the potential utility of MB in FT for localized PCa. METHODS: A 38-item questionnaire was built following a literature search. The authors then performed three rounds of a Delphi Consensus using DelphiManager, using the GRADE grid scoring system, followed by a face-to-face expert meeting. Three areas of interest were identified and covered concerning MB for FT, 1) the current/present role; 2) the potential/future role; 3) the recommended features for future studies. Consensus was defined using a 70% agreement threshold. RESULTS: Of 95 invited experts, 42 (44.2%) completed the three Delphi rounds. Twenty-four items reached a consensus and they were then approved at the meeting involving (N.=15) experts. Fourteen items reached a consensus on uncertainty, or they did not reach a consensus. They were re-discussed, resulting in a consensus (N.=3), a consensus on a partial agreement (N.=1), and a consensus on uncertainty (N.=10). A final list of statements were derived from the approved and discussed items, with the addition of three generated statements, to provide guidance regarding MB in the context of FT for localized PCa. Research efforts in this field should be considered a priority. CONCLUSIONS: The present study detailed an initial consensus on the use of MB in FT for PCa. This is until evidence becomes available on the subject

Utilization of focal therapy for patients discontinuing active surveillance of prostate cancer: Recommendations of an international Delphi consensus

BackgroundWith the advancement of imaging technology, focal therapy (FT) has been gaining acceptance for the treatment of select patients with localized prostate cancer (CaP). We aim to provide details of a formal physician consensus on the utilization of FT for patients with CaP who are discontinuing active surveillance (AS).MethodsA 3-stage Delphi consensus on CaP and FT was conducted. Consensus was defined as agreement by ≥80% of physicians. An in-person meeting was attended by 17 panelists to formulate the consensus statement.ResultsFifty-six respondents participated in this interdisciplinary consensus study (82% urologist, 16% radiologist, 2% radiation oncology). The participants confirmed that there is a role for FT in men discontinuing AS (48% strongly agree, 39% agree). The benefit of FT over radical therapy for men coming off AS is: less invasive (91%), has a greater likelihood to preserve erectile function (91%), has a greater likelihood to preserve urinary continence (91%), has fewer side effects (86%), and has early recovery post-treatment (80%). Patients will need to undergo mpMRI of the prostate and/or a saturation biopsy to determine if they are potential candidates for FT. Our limitations include respondent's biases and that the participants of this consensus may not represent the larger medical community.ConclusionsFT can be offered to men coming off AS between the age of 60 to 80 with grade group 2 localized cancer. This consensus from a multidisciplinary, multi-institutional, international expert panel provides a contemporary insight utilizing FT for CaP in select patients who are discontinuing AS