PTFOS: Flexible and Absorbable Intracranial Electrodes for Magnetic Resonance Imaging

Intracranial electrocortical recording and stimulation can provide unique knowledge about functional brain anatomy in patients undergoing brain surgery. This approach is commonly used in the treatment of medically refractory epilepsy. However, it can be very difficult to integrate the results of cortical recordings with other brain mapping modalities, particularly functional magnetic resonance imaging (fMRI). The ability to integrate imaging and electrophysiological information with simultaneous subdural electrocortical recording/stimulation and fMRI could offer significant insight for cognitive and systems neuroscience as well as for clinical neurology, particularly for patients with epilepsy or functional disorders. However, standard subdural electrodes cause significant artifact in MRI images, and concerns about risks such as cortical heating have generally precluded obtaining MRI in patients with implanted electrodes. We propose an electrode set based on polymer thick film organic substrate (PTFOS), an organic absorbable, flexible and stretchable electrode grid for intracranial use. These new types of MRI transparent intracranial electrodes are based on nano-particle ink technology that builds on our earlier development of an EEG/fMRI electrode set for scalp recording. The development of MRI-compatible recording/stimulation electrodes with a very thin profile could allow functional mapping at the individual subject level of the underlying feedback and feed forward networks. The thin flexible substrate would allow the electrodes to optimally contact the convoluted brain surface. Performance properties of the PTFOS were assessed by MRI measurements, finite difference time domain (FDTD) simulations, micro-volt recording, and injecting currents using standard electrocortical stimulation in phantoms. In contrast to the large artifacts exhibited with standard electrode sets, the PTFOS exhibited no artifact due to the reduced amount of metal and conductivity of the electrode/trace ink and had similar electrical properties to a standard subdural electrode set. The enhanced image quality could enable routine MRI exams of patients with intracranial electrode implantation and could also lead to chronic implantation solutions

The Prevalence and Characteristics of Older Japanese Adults with Polypharmacy, Based on Regionally Representative Health Insurance Claims Data

We aimed to clarify the prevalence of polypharmacy among elderly individuals in Japan. We used the data obtained from a large-scale population-based representative database of health insurance claims in a single prefecture in Japan. We examined all of the outpatient and pharmaceutical health insurance claims for National Health Insurance and those for Late-stage Elderly Health Insurance in Nagasaki Prefecture, Japan between April and June 2016. When two or more claim forms were issued for a patient in a single month, we combined the data and identified the number of prescribed drugs for each person. The definition of polypharmacy is a the prescription of six or more drugs per month. We investigated the prevalence of polypharmacy among the beneficiaries of the two insurance systems. Of the 605,406 beneficiaries of the 2 insurance systems, 121,033 (20.0%) patients with polypharmacy were identified. The prevalence of polypharmacy increased with age, especially among the beneficiaries aged > 85 years, with about half of the beneficiaries having polypharmacy status. About half of the people aged > 85 years in the database had polypharmacy status. When a drug is prescribed to an elderly individual, it is necessary to consider the possibility of polypharmacy-related problems

NICU nurses' perceptions of nursing practice based on family-centered care

目的 : わが国では，1970年代終わりに新生児看護実践にfamily-centered careが取り入れられ始め，その後，family-centered developmental careの普及とともに，family-centeredであることに関心が向けられるようになった．しかし今日，NICU看護師が，自分自身のFCCに基づいた実践をどのように捉え，かつ，実践を困難にさせる理由をどのように捉えているかは十分明らかにされていない．そこで本研究では，FCCに基づいた看護実践に関するNICU看護師の認識を調査し，FCCを推進するための課題を考察することとした． 方法 : 無記名式の構成型質問紙調査を郵送法によって行った．対象者は日本新生児看護学会員674名とし，平成23年4月と平成24年5月に実施した．質問内容は，回答者の背景,FCCに基づいた看護実践，FCCに基づいた看護実践が困難な理由とした．分析は，基本統計量の算出，t検定，一元配置分散分析によって行った． 結果 : 340名から回答を得た(51.4%)．1)各基本概念の平均得点は，「心がけている」「実践している」とも，有意に「参加」が高く，「協働」が低かった．2)基本概念のいずれにおいても，「実践している」より「心がけている」の得点が有意に高かった．3)FCCに基づいた看護実践が困難な理由は，知識や実務の側面が上位を占め，最も多かったのは「医師，看護スタッフ・師長が，FCCの理念を実践化する方法を知らない」であった．4)FCCに基づいた看護実践が困難な理由は，年齢，総臨床経験年数NICU経験年数，他領域経験年数と関連した． 結論 : FCCの推進には，ガイドラインの作成および教育・訓練が重要な課題であることが考えられた．Objectives: Family-centered care was introduced into neonatal nursing practice in Japan at the end of the 1970s. It attracted much interest with the spread of family-centered development care. Today, however, what NICU nurses think about their practice based on FCC, and the reasons it is difficult to practice are not clearly understood. We therefore surveyed the perceptions of NICU nurses on nursing practice based on FCC, and discussed ways of promoting FCC. Methods: An anonymous structured question survey was sent by mail to 674 members of the Japan Academy of Neonatal Nursing in April 2011 and May 2012. Questions asked were on the respondents' background, nursing practice based on family-centered care, and reasons why practicing FCC was difficult. Data were descriptively analyzed and then a t - test and a one- way ANOVA were carried out. Results: 340 valid responses were received (51.4%). 1) Concerning practicing or being mindful of the basic concept of FCC, "participation" scored significantly highly, while the score for "collaboration" was low. 2) For all the basic concepts, the response "mindful" scored significantly higher than "practice". 3) As for the reasons why nursing practice based on FCC is difficult, most issues were related to knowledge and practice. The most frequent response was "doctors, nursing staff, and head nurses do not know how to practice the concept of FCC". 4) The difficulty of nursing practice based on FCC correlated with age and years of total clinical experience, NICU experience, and experience in other areas. Conclusion: Developing the Guidelines and providing education and training are considered necessary to promote nursing practice based on FCC.本研究は日本学術振興会科学研究費補助金基盤研究(B)22390430の助成を受けた研究の一部である

Radio-Frequency Safety Assessment of Stents in Blood Vessels During Magnetic Resonance Imaging

Purpose: The purpose of this study was to investigate the need for high-resolution detailed anatomical modeling to correctly estimate radio-frequency (RF) safety during magnetic resonance imaging (MRI). RF-induced heating near metallic implanted devices depends on the electric field tangential to the device (Etan). Etan and specific absorption rate (SAR) were analyzed in blood vessels of an anatomical model to understand if a standard gel phantom accurately represents the potential heating in tissues due to passive vascular implants such as stents.Methods: A numerical model of an RF birdcage body coil and an anatomically realistic virtual patient with a native spatial resolution of 1 mm3 were used to simulate the in vivo electric field at 64 MHz (1.5 T MRI system). Maximum values of SAR inside the blood vessels were calculated and compared with peaks in a numerical model of the ASTM gel phantom to see if the results from the simplified and homogeneous gel phantom were comparable to the results from the anatomical model. Etan values were also calculated in selected stent trajectories inside blood vessels and compared with the ASTM result.Results: Peak SAR values in blood vessels were up to ten times higher than those found in the ASTM standard gel phantom. Peaks were found in clinically significant anatomical locations, where stents are implanted as per intended use. Furthermore, Etan results showed that volume-averaged SAR values might not be sufficient to assess RF safety.Conclusion: Computational modeling with a high-resolution anatomical model indicated higher values of the incident electric field compared to the standard testing approach. Further investigation will help develop a robust safety testing method which reflects clinically realistic conditions

MRI Analysis of White Matter Myelin Water Content in Multiple Sclerosis: A Novel Approach Applied to Finding Correlates of Cortical Thinning

A novel lesion-mask free method based on a gamma mixture model was applied to myelin water fraction (MWF) maps to estimate the association between cortical thickness and myelin content, and how it differs between relapsing-remitting (RRMS) and secondary-progressive multiple sclerosis (SPMS) groups (135 and 23 patients, respectively). It was compared to an approach based on lesion masks. The gamma mixture distribution of whole brain, white matter (WM) MWF was characterized with three variables: the mode (most frequent value) m1 of the gamma component shown to relate to lesion, the mode m2 of the component shown to be associated with normal appearing (NA) WM, and the mixing ratio (λ) between the two distributions. The lesion-mask approach relied on the mean MWF within lesion and within NAWM. A multivariate regression analysis was carried out to find the best predictors of cortical thickness for each group and for each approach. The gamma-mixture method was shown to outperform the lesion-mask approach in terms of adjusted R2, both for the RRMS and SPMS groups. The predictors of the final gamma-mixture models were found to be m1 (β = 1.56, p \u3c 0.005), λ (β = −0.30, p \u3c 0.0005) and age (β = −0.0031, p \u3c 0.005) for the RRMS group (adjusted R2 = 0.16), and m2 (β = 4.72, p \u3c 0.0005) for the SPMS group (adjusted R2 = 0.45). Further, a DICE coefficient analysis demonstrated that the lesion mask had more overlap to an ROI associated with m1, than to an ROI associated with m2 (p \u3c 0.00001), and vice versa for the NAWM mask (p \u3c 0.00001). These results suggest that during the relapsing phase, focal WM damage is associated with cortical thinning, yet in SPMS patients, global WM deterioration has a much stronger influence on secondary degeneration. Through these findings, we demonstrate the potential contribution of myelin loss on neuronal degeneration at different disease stages and the usefulness of our statistical reduction technique which is not affected by the typical bias associated with approaches based on lesion masks

X-ray Spectral Study of the extended emission,'the Cap', located 11.6 kpc above the disk of M82

The extended X-ray emission from 'the Cap' region located 11' (11.6 kpc) above the disk of the starburst galaxy M82 has been observed with Suzaku and XMM-Newton. Owing to the good energy resolution and the large collecting area of the XIS on Suzaku, combined with similar properties of the EPIC instrument on XMM-Newton, we have clearly detected K-shell emission lines from O VII, O VIII, Ne X, Mg XI, Mg XII and the Fe-L complex. Two optically-thin thermal plasma components are required to fit the observed X-ray spectra. We have determined the metal abundances of O, Ne, Mg, Si and Fe in this region for the first time. Their metal abundance ratios agree well with those of metal-poor stars and the model prediction of metals synthesized by type-II supernovae, but they are not consistent with the metallicities of type-Ia supernovae. This result is support for the idea that the origin of the metals in the Cap is type-II supernovae explosions occurring in the starburst regions in the M82 galaxy. We discuss the possible contribution from sputtered dust grains to the metals in the Cap. An emission line consistent with the C VI transition of n=4 to 1 at 0.459 keV is marginally detected, although it is not statistically significant at the 99% confidence level; the presence of this line would suggest charge-exchange processes in the Cap.Comment: 16 pages, 10 figuer

Reversible visual disturbance due to cryptococcal uveitis in a non-HIV individual.

A 52-year-old man without underlying diseases visited a local hospital with symptoms of memory deficit and mild headache. Radiological examination of the brain with computed tomography (CT) revealed hydrocephalus. Etiology was not revealed by cerebrospinal fluid (CSF) analysis and a ventricular-atrial (V-A) shunt was installed. The patient had congestion and dacryorrhea of the right eye and uveitis was diagnosed three months after placement of the V-A shunt. The serum cryptococcal antigen (CrAg) tested positive at a titration of 64 times. Additionally, samples of the right eye anterior chamber aqueous humor (ACAH), cerebrospinal fluid (CSF) and prostate fluid were positive for Cryptococcus antigen at a titration of 128 times. In addition, Cryptococcus neoformans var. grubii was isolated from the peripheral blood, CSF and ACAH, resulting in a diagnosis of disseminated cryptococcosis. Fluconazole (FLCZ) at 800 mg/day was administered for the first two days, followed by a 400 mg/day maintenance dose. After six months of treatment, his visual power recovered. This is a rare case of disseminated cryptococcosis involving uveitis, which was successfully treated by FLCZ. Disseminated cryptococcosis should be considered in cases with mild symptoms and V-A shunt installation for hydrocephalus

The Iron Discrepancy in Elliptical Galaxies after ASCA

We present estimates for the iron content of the stellar and diffused components of elliptical galaxies, as derived respectively from integrated optical spectra and from ASCA X-ray observations. A macroscopic discrepancy emerges between the expected iron abundances in the hot interstellar medium (ISM) and what is indicated by the X-ray observations, especially when allowance is made for the current iron enrichment by Type Ia supernovae. This strong discrepancy, that in some extreme instances may be as large as a factor of $\sim 20$, calls into question our current understanding of supernova enrichment and chemical evolution of galaxies. We discuss several astrophysical implications of the inferred low iron abundances in the ISM, including the chemical evolution of galaxies and cluster of galaxies, the evolution of gas flows in ellipticals, and the heating of the intracluster medium. Some of the consequences appear hard to accept, and in the attempt to avoid some of these difficulties we explore ways of hiding or diluting iron in the ISM of ellipticals. None of these possibilities appears astrophysically plausible, and we alternatively rise the question of the reliability of iron-L line diagonostic tools. Various thin plasma emission models are shown to give iron abundances that may differ significantly, especially at low temperatures (kT \lsim 1 keV). From a collection of ASCA and other X-ray observatory data, it is shown that current thin plasma codes tend to give very low iron abundances when the temperature of the objects is below $\sim 1$ keV. We conclude that -- besides rethinking the chemical evolution of galaxies -- one should also consider the possibility that existing thin plasma models may incorporate inaccurate atomic physics for the ions responsible for the iron-L complex.Comment: 39 pages, TeX file, 5 figures, Accepted for publication in the Ap

Search for Oxygen Emission from Warm-Hot Intergalactic Medium around A2218 with Suzaku

We searched for redshifted O emission lines from the possible warm-hot intergalactic medium (WHIM) surrounding the cluster of galaxies A2218 at z=0.1756 using the XIS instrument on Suzaku. This cluster is thought to have an elongated structure along the line of sight based on previous studies. We studied systematic uncertainties in the spectrum of the Galactic emission and in the soft X-ray response of the detectors due to the contamination building up on the XIS filters. We detected no significant redshifted O lines, and set a tight constraint on the intensity with upper limits for the surface brightness of OVII and OVIII lines of 1.1 x 10^-7 and 3.0 x 10^-7 photons cm^-2 s^-1 arcmin^-2, respectively. These upper limits are significantly lower than the previously reported fluxes from the WHIM around other clusters of galaxies. We also discuss the prospect for the detection of the WHIM lines with Suzaku XIS in the future.Comment: 12 pages, 13 figures. Accepted for publication in PASJ Suzaku special issue (Vol.59, No.SP1

Altered Energy Homeostasis and Resistance to Diet-Induced Obesity in KRAP-Deficient Mice

Obesity and related metabolic disorders have become leading causes of adult morbidity and mortality. KRAP (Ki-ras-induced actin-interacting protein) is a cytoskeleton-associated protein and a ubiquitous protein among tissues, originally identified as a cancer-related molecule, however, its physiological roles remain unknown. Here we demonstrate that KRAP-deficient (KRAP−/−) mice show enhanced metabolic rate, decreased adiposity, improved glucose tolerance, hypoinsulinemia and hypoleptinemia. KRAP−/− mice are also protected against high-fat diet-induced obesity and insulin resistance despite of hyperphagia. Notably, glucose uptake in the brown adipose tissue (BAT) in KRAP−/− mice is enhanced in an insulin-independent manner, suggesting that BAT is involved in altered energy homeostasis in KRAP−/− mice, although UCP (Uncoupling protein) expressions are not altered. Of interest is the down-regulation of fatty acid metabolism-related molecules, including acetyl-CoA carboxylase (ACC)-1, ACC-2 and fatty acid synthase in the liver of KRAP−/− mice, which could in part account for the metabolic phenotype in KRAP−/− mice. Thus, KRAP is a novel regulator in whole-body energy homeostasis and may be a therapeutic target in obesity and related diseases