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BackgroundThe prolonged presence of infectious severe acute respiratory syndrome coronavirus (SARS-CoV-2) in deceased coronavirus disease 2019 (COVID-19) patients has been reported. However, infectious virus titers have not been determined. Such information is important for public health, death investigation, and handling corpses.AimThe aim of this study was to assess the level of SARS-CoV-2 infectivity in COVID-19 corpses.MethodsWe collected 11 nasopharyngeal swabs and 19 lung tissue specimens from 11 autopsy cases with COVID-19 in 2021. We then investigated the viral genomic copy number by real-time reverse transcription-polymerase chain reaction and infectious titers by cell culture and virus isolation.ResultsInfectious virus was present in 6 of 11 (55%) cases, 4 of 11 (36%) nasopharyngeal swabs, and 9 of 19 (47%) lung specimens. The virus titers ranged from 6.00E + 01 plaque-forming units (PFU)/mL to 2.09E + 06 PFU/g. In all cases in which an infectious virus was found, the time from death to discovery was within 1 day and the longest postmortem interval was 13 days.ConclusionCOVID-19 corpses may have high titers of infectious virus after a long postmortem interval (up to 13 days). Therefore, appropriate infection control measures must be taken when handling corpses.

Objective: The mental health issues of personnel dealing with the deceased at times of disasters is a problem and techniques are needed that allow for real-time, easy-to-use stress checks. We have studied techniques for measuring mental state using voice analysis which has the benefit of being non-invasive, easy-to-use, and can be performed in real-time. For this study, we used voice measurement to determine the stress experienced during body identification training workshops for dentists. We studied whether or not stress levels were affected by having previous experience with body identification either in actual disaster settings or during training. Design: Since participants training using actual dead bodies in particular are expected to suffer higher stress exposure, we also assessed their mental state pre- and post-training using actual dead bodies. Results: The results confirmed marked differences in the mental state between before and after training in participants without any actual experience, between participants who engaged in training using manikins before actual dead bodies and participants who did not. Conclusions: These results suggest that, in body identification training, the level of stress when coming into contact with dead bodies varies depending on participants’ experience and the training sequence. Moreover, it is believed that voice-based stress assessment can be conducted in the limited time during training sessions and that it can be usefully implemented in actual disaster response settings.

We show theoretically and experimentally that accurate transport measurements are possible even within the short time provided by pulsed magnetic fields. For this purpose, a new method has been devised, which removes the noise component of a specific frequency from the signal by taking a linear combination of the results of numerical phase detection using multiple integer periods. We also established a method to unambiguously determine the phase rotation angle in AC transport measurements using a frequency range of tens of kilohertz. We revealed that the dominant noise in low-frequency transport measurements in pulsed magnetic fields is the electromagnetic induction caused by mechanical vibrations of wire loops in inhomogeneous magnetic fields. These results strongly suggest that accurate transport measurements in short-pulsed magnets are possible when mechanical vibrations are well suppressed.

Swelling characteristics of hydrogen storage alloy (HSA) with hydrogen content change were experimentally determined. Its kinetic behavior is important for an HSA actuator which is driven by the volume change of the HSA in a hydrogen atmosphere. Although hydrogen absorption characteristics of the alloy are expected to be strongly related to the actuator performance, it is difficult to clarify the relationship using the previous HSA actuators which consist of plural materials. In this paper, the authors investigated the swelling ratio and the response time of palladium powder in a hydrogen atmosphere. As a result, the swelling ratio increased with hydrogen absorption amount. The response time increased with hydrogen pressure during pressurization, while it was independent of pressure. It was revealed from reaction kinetics that a rate-limiting step was diffusion and interfacial reaction during the pressurization and the evacuation, respectively. Thus, the swelling property of palladium is determined from its hydrogen absorption behavior, which suggests the HSA actuator can be designed based on hydrogen storage characteristics.

Hairs are often used for DNA analysis in criminal investigations. DNA analysis of hairs with root sheaths is easy in many cases, but analyses using only the shaft or tip of the hair are often difficult. Here we describe a suspected case of child abuse in which we were commissioned to perform DNA analysis. Among 100 hairs, PCR amplification was succeeded in 99 samples, and as a result of direct sequencing, mitochondrial DNA (mtDNA) of the 99 hairs were classified into 6 types. The most common type was the 8-base substitution type of 16,168T-16,172C-16,183C-16,189C-16,217C-16,249C-16,325C-16,390A, which was observed in 86 hairs. This corresponded to the type of the victim. Total 736 STRs (75.5%) in 975 loci of 65 hairs could be typed, and only an amelogenin locus was typed in another hair. All 15 loci were typed in 10 hairs. STR types of 65 (98.5%) in 66 hairs were consistent with that of the victim. From 10 naturally-shed hair of a person, only 37 STRs (30.8%) in 120 loci of 8 hairs were typed, and all 15 loci could not be typed in these hairs. This difference in success rates of STR analysis suggested strongly that the hairs in this case were not shed naturally but forcibly, and the relevance to child abuse was suspected.

The swelling ability of LaNi5 for application to hydrogen-storage-alloy (HSA) actuator is discussed through the measurement of the swelling ratio in hydrogen. The HSA actuator is driven by hydrogen pressure change causing the swelling of HSA. LaNi5 is one of the candidate materials for HSA actuators as well as palladium. Some prototypes of HSA actuators using LaNi5 have been fabricated, however, the kinetic swelling ability of LaNi5 itself has been not investigated. In this paper, the authors investigated the static and kinetic swelling ability of LaNi5 powder under hydrogen atmosphere. The results showed that the swelling ratio increased by 0.12 at the phase transition pressure. Response time decreased with an increase in the charged pressure during absorption, while it remained constant during discharge. Reaction kinetics revealed that these swelling behaviors were explained by hydrogen absorption and lattice expansion. The swelling ability of LaNi5 was also compared with that of palladium. The results show that LaNi5 swells 1.8 times more than palladium under 0.5 MPa. LaNi5 is suitable for an actuator driven repeatedly under more than the phase transition pressure. Palladium can be used for one-way-operation actuator even under 0.1 MPa since its response time during the evacuation was much longer than during the pressurization.

The epidemiology of patients with traumatic brain injury (TBI) has changed dramatically over recent decades as a result of rapid advances in aging societies. We assessed the influence of age on outcomes of patients with TBI and sought to identify prognostic factors for in-hospital mortality of TBI among elderly patients.Using a nationwide database, we analyzed data from 5651 patients with TBI. Univariate analysis was conducted to compare patient demographics, neurologic status on admission, radiologic findings, systemic complication rates, length of hospital stay, in-hospital mortality, and home discharge rates between elderly and nonelderly groups. Multivariable analysis was conducted to determine prognostic factors for in-hospital mortality among elderly patients.Overall in-hospital mortality was significantly higher in elderly patients (12.8% vs. 19.3%; P0.001). In-hospital mortality of elderly patients with mild TBI increased significantly at7 days after admission, whereas that of elderly patients with moderate or severe TBI was significantly higher immediately after admission. Age (odds ratio [OR], 1.62; P = 0.024), male sex (OR, 1.30; P = 0.004), Japan Coma Scale score on admission (OR, 5.95, P0.001), and incidence of acute subdural hematoma (OR, 1.89; P0.001) were associated with in-hospital mortality in elderly patients with TBI.Elderly patients with TBI showed significantly higher in-hospital mortality. Delayed increases in in-hospital mortality were observed among elderly patients with mild TBI. Level of consciousness on admission was the strongest predictor of in-hospital mortality among elderly patients.

c-axis oriented Si3N4 ceramics were fabricated by applying a low static magnetic field. Conventionally, c-axis oriented Si3N4 ceramics are fabricated using a rotating magnetic field of over 10 T considering the anisotropy and the magnitude of diamagnetic susceptibility between c- and a-axes. In this work, multilayered-graphene was used for orienting rod-like β-Si3N4 particles as graphene exhibits a high diamagnetic anisotropy. The multilayered-graphene was coated with their orientation on the surface of rod-like β-Si3N4 particles by using a mechanical treatment process. As a result, the c-axis of multilayered-graphene-coated β-Si3N4 particles were oriented parallel direction to the applied magnetic field even at 0.4 T. In addition, c-axis oriented Si3N4 ceramics were fabricated successfully by adding a small quantity of multilayered-graphene-coated β-Si3N4 particles as seeds. The thermal conductivity of the c-axis oriented Si3N4 ceramics prepared with a magnetic field of 0.4 T exhibited anisotropy with a higher value achieved in the c-axis oriented direction.

In Japan, dental charting following a disaster is performed by handwriting the information on a paper-based dental chart before manual input into a computer database. Even if available, radiographic facial or intraoral images, regardless of whether they are analogue or digital, must be stored separately from the dental chart. To create a comprehensive and more permanent database accessible worldwide, we developed a system employing digital pens with image microprocessors. This system digitizes and records characters and drawings as they are being handwritten on a microdotted-paper-based post-mortem dental chart. Data stored in the built-in memory of the digital pen are transferred to a computer or tablet via Bluetooth. Using a cognitive wireless router, the information is relayed to a remote data centre. Radiographic and other images are also transferred into the same folder under a unique ID number. After several practical field tests, the system was employed at a landslide disaster in Hiroshima ...

As cerebrovascular anastomosis is performed in moist conditions that may impede precise manipulations, surgeons must undergo extensive preoperative training. We developed a simple moist-condition training method. It involves placing a free-floating inner platform hosting an artery from a chicken wing in an outer container filled with tap water to just below the specimen. Trainees performed anastomosis under magnification. Training sessions mimicked difficulties encountered during operations such as poor visibility of the lumen and problems handling the sutures. A retrospective comparison of 100 wet- and 100 dry-condition training sessions for end-to-side anastomoses with 8 stitches showed that under moist condition the time required for the entire procedure was significantly longer (17.8 ± 2.1 vs. 15.3 ± 2.1 min, p < 0.01) and the incidence of wrong stitching was greater (0.38 vs. 0%, p = 0.04). In 8 cases after introducing moist-condition training, the time required in superficial temporal artery to middle cerebral artery bypass surgery was significantly shorter than 8 cases before introducing the training (32.3 ± 5.6 min vs. 48.3 ± 15.9 min, p = 0.01). Incidence of wrong stitches was less in cases after introducing moist-condition training (2.7 vs. 7.4%, p = 0.10). Those indicate that moist-condition training is a useful and practical step and a bridge between training for basic manipulations under dry conditions and actual surgery.

We performed electric polarization P, dielectric constant ϵ and magnetization M measurements on the perfect triangular-lattice antiferromagnet RbFe(MoO4)2 in high magnetic fields B applied along the c-axis. Whereas M(B) at T=1.5 K monotonically increases with B up to the saturation at B s = 21 T , P(B) disappears about 14 T, far below the saturation point. In a field range 13 ≤ B ≤ 14 T , the temperature variation of ϵ shows a double peak structure below 2.8 K, indicating two successive transitions. These results strongly suggest the presence of a new high-field phase; the magnetic structure changes from a low-field conical state having chirality to a high-field coplanar non-collinear structure without chirality. The obtained phase diagram is in agreement with a theoretical prediction on XY-like Heisenberg spin triangular lattice antiferromagnets.

Earthquake-related anomalous electromagnetic phenomena have been reported in various frequency ranges over the past few decades. Investigation of the anomalous propagation of VHF transmitter waves is a promising approach to short-term prediction and crustal activity monitoring. Anomalous propagation is believed to be generated by disturbances of the atmosphere above the epicenter or along the propagation path prior to large earthquakes. Consequently, over-the-horizon propagation has been received. A recent study shows that the appearance of anomalies was significantly enhanced within 5 days of earthquakes with M ≥4.8. However, there is no information on the scattering location, that is, on the direction of wave arrival. Therefore, a simple interferometer system for VHF radio waves to identify the space-time position of earthquake-related atmospheric disturbances has been developed and installed at Chiba University. This paper describes the newly developed interferometer system and presents the results of fundamental tests to evaluate the performance of the new interferometer at Chiba. Data on over-the-horizon propagation of VHF radio waves obtained from 1-year continuous measurement at Chiba are described. These are possible radio duct propagations and possible earthquake-related anomalous propagations. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(1): 16–24, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22303

The deuteration-induced effect on the Fermi surface (FS) topology of V was investigated by the synchrotron-based Compton scattering technique with 115 keV X-rays. The three-dimensional occupation number density (OND) of α-VD 0.64 single crystal and V single crystal was reconstructed by the directional Compton profiles along 13–18 directions. The observed OND shows that the FS topology of α-VD 0.64 .differs from that of V at Γ, N, and H points in the crystal momentum space, which are hole position for V. This indicates that electrons that originate from deuterium modify the upper part of the host metal d bands (3rd and 4th bands) at the Fermi level E F , and forms the metal–hydrogen bonding states with the lower part of the host metal d band (1st band).

We have installed a shift register system of ex- tensive air show (EAS) particles in a compact EAS array built on the rooftop of the Faculty of Engineering building in the campus of Okayama University of Science and be- ing operated since April 2006 as part of Large Area Air Shower (LAAS) experiments , in order to register each ar- rival time of EAS particles within 5µs. Detector simulations based on the database obtained from one of the standard cos- mic ray propagation simulator in the atmosphere (AIRES) have also been carried out and the procedures to estimate the primary cosmic ray energy from the Linsley's method have been developed and examined. Applying Linsley's method to the EAS data obtained by our EAS arrays and the simula- tion results, we derived the energy spectrum from 10 16 eV to 10 19.5 eV. Consequently, we obtained the power-law index of 3.2(+0.46 0.8) in the primary energy range of 10 16 eV to 10 18.5 eV, and obtained that a change around 10 18 eV ap- peared if not taking account of the zenith angle distribution of primary cosmic rays. We compared the obtained energy spectrum with other experimental data above 10 16 eV ener- gies, and showed the two components of power-law energy spectra well described our data. We also showed the im- provement of energy resolution by applying the restriction of zenith angle of primary cosmic rays in our simulation re

Earthquake-related anomalous electromagnetic phenomena have been reported in various frequency ranges in a few decades. Investigation on the anomalous propagation of VHF transmitter waves is one of promising approaches on the short-term prediction and crustal activity monitoring. The anomalous propagation is considered to be generated by disturbances of the atmosphere above the epicenter or along the propagation path prior to large earthquakes. Consequently, over-horizontal propagation has been received. A recent study shows that the appearance of anomalies was significantly enhanced within 5 days before earthquakes with M ≥ 4.8. However, there is no information on the scattered place, that is, the direction of wave arrival. Therefore, a simple interferometer system for VHF radio wave to identify the position between space-time of earthquake-related atmospheric disturbances has been developed and installed at Chiba University. In this paper, we will show you the developed interferometer system and results of fundamental tests to evaluate the performance of developed and installed interferometer at Chiba. In addition, facts on invisible propagation of VHF radio wave obtained from 1-year continuous measurement at Chiba are described in this paper. Those are possible radio duct propagations and possible earthquake-related anomalous propagations.

Al-doped ZnO (AZO) films were deposited on fused silica glass substrates unheated or heated at 200 °C by reactive dc sputtering using a Zn–Al alloy target with mid-frequency pulsing (50 kHz) and the plasma control unit with a feedback system of the optical emission intensity of the atomic O* line at 777 nm to control oxygen gas flow. The stable and reproducible depositions were successfully carried out in the transition region. The deposition rates attained in this study were about 10–20 times higher than the one by conventional sputtering using oxide targets. The AZO films with the lowest resistivity of 3.8 × 10− 4 Ω cm was deposited on the substrate heated at 200 °C with a sputter power of 4 kW, where the deposition rate was 385 nm/min.

A compact extensive air shower (EAS) array of eight plastic scintillators viewed by HAMAMATSU H7195 photomultiplier tubes covering a total area of 2 m 2 is built in the rooftop of the Faculty of Technology building, Okayama University of Science, and operated since April 2006. We have installed a shift register system in our EAS array to record EAS particle arrival time within 5 μ s . We have also performed detector simulations based on the database obtained from the AIRES simulator and developed the procedures to estimate the primary cosmic ray energy from Linsley's method. Applying this method to our EAS data and the simulation result, we derived the energy spectrum from 10 16 to 10 19.5 eV . Consequently, we obtained the power-law index of − 3.2 ( + 0.46 − 0.8 ) in the primary energy range of 10 16 to 10 18.5 eV , and obtained that a change around 10 18 eV appeared if not taking account of the zenith angle distribution of primary cosmic rays. We also showed the improvement of energy resolution by applying the restriction of zenith angle of primary cosmic rays in our simulation, as well as the potential of Linsley's method with a mini array.

We have developed a practical urea monitor based on a chemiluminescent (CL) reaction of urea and hypobromous acid produced by electrolysis of sodium bromide (NaBr) for measuring urea concentration in spent dialysate at set intervals. A reagent containing 4×10-2 M hypobromous acid is produced by electrolysis of an electrolyte containing 5.9 M NaBr and 0.2 M sodium hydroxide (NaOH). Chemiluminescence is emitted by injection of spent hemodialysis fluid (0.11 ml) into the reagent, and the CL-intensity is measured by a photomultiplier tube using the photon counting technique. The CL-intensity is proportional to the 0.9th power of the urea concentration between 7×10-4 and 2×10-2 M. The urea monitor can determine the urea concentration in spent dialysate samples collected from the waste line of a dialyzer, and the time for the intermittent measurements including the cleaning cycle of the reaction chamber is 3 min. The urea concentrations measured by the monitor are in close agreement with those measured by the conventional enzyme colorimetric method using urease for the spent dialysate collected during a hemodialysis treatment, and the correlation coefficient is 0.93.

We have measured extensive air showers (EAS) with primary cosmic ray energies above PeV at multiple EAS observatories deployed in Japan since 1996. Each array has been located on the rooftops of buildings in the university campus, and has a GPS-disciplined 10 MHz oscillator to provide UTC time stamps for each EAS event with microsecond accuracies. We have carried out a search for simultaneous and parallel EAS events at multiple EAS sites, such as Gerasimova-Zatsepin events, by comparing the EAS arrival time stamp and directions between long baseline EAS arrays. We selected EAS pairs for which the time difference and angular distance were less than 15 ° and 5 msec respectively and then examined the angular distances of these events from the solar and lunar directions. Consequently, we conclude that we do not find any excesses of these events in the solar direction so far, as expected in the theoretical prediction of GZ effects. We found deficiencies of EAS pairs in the lunar direction, but its deviation is not significant.

The primary energy of cosmic rays in the energy region above 10 16 eV has been studied with the use of a compact extensive air shower (EAS) array which consists of 8 scintillation counters in 200m 2 area. We report on the simulation results for estimating the primary energy and its spectrum by using Linsley's method, and on the improvement of the determination accuracy of the primary energy by applying the zenith angle restricted observation of EAS muons with the new array as well as a brief description of the apparatus.

目的：顎関節脱臼は神経疾患に起因することがあるが，その認知度は低い．今回，脳卒中における顎関節脱臼の臨床像を明らかにし，患者管理に活用するため自験例を検討した． 方法：当センター歯科外来病歴データベースより該当症例を抽出・検討した． 結果：10例の成人脳卒中患者（片麻痺6例，四肢麻痺3例，運動麻痺なし1例）に顎関節脱臼がみられた．脱臼は片側性2例，両側性8例であった．脳卒中発症から12日∼9カ月（平均94.1日）で発症しており，9例は用手整復・外固定で寛解したが，1例は整復手術を要した． 結論：下顎骨を顎関節に引き上げる閉口筋は，咬筋・側頭筋・内側翼突筋であり，これらは核上部では両側支配の三叉神経運動枝に支配される．しかし片側脳卒中であっても閉口筋力が低下することはあり，閉口筋の機能には両側神経支配が揃うことが不可欠である．稀ながら顎関節脱臼が，脳卒中後の閉口筋力低下によることがあり，早期の発見・整復のためこれを銘記する必要がある．

Temporal correlation between atmospheric anomalies and earthquakes has recently been verified statistically through measuring VHF FM radio waves transmitted beyond the line-of-sight. In order to locate the sources of such atmospheric anomalies, we developed a VHF interferometer system (bistatic-radar type) capable of finding the arrival direction of FM radio waves scattered possibly by earthquake-related atmospheric anomalies. In general, frequency modulation of FM radio waves produces ambiguity of arrival direction. However, our system, employing high-sampling rates of the order of kHz, can precisely measure the arrival direction of FM radio waves by stacking received signals.

The present study proposes a method for improving an existing technique used for extracting the centerlines of coronary arteries with calcifications on CTA. Through the use of the improved centerline extraction method, CPR images could be depicted accurately. In the proposed method, two dynamic range compression algorithms using two ITC for blood vessel regions and calcification regions were employed. Two dynamic range compressed CTA images obtained from the two ITC were then subtracted. After that, automatic tracing to determine the centerline for creating CPR images was performed using 3D image processing equipment. The usefulness of our proposed method was confirmed by using simulated CTA of the coronary artery with calcification. We also applied the proposed method to CTA images of 39 branches in 18 cases, and to 48 segments. Our experimental results showed that automatic tracing software pre-installed in the workstation could accurately determine the centerline of the coronary artery without being affected by the existence of calcification. Furthermore, an experienced radiological technologist evaluated the CPR images obtained by the proposed method. The results showed that most created CPR images could be used as diagnostic images after a minor revision performed manually.

Object Plaque hemorrhage in carotid atherosclerosis promotes plaque progression, resulting in cerebrovascular disease. Hypoxia inducible factor–1α (HIF-1α) induces angiogenesis via the expression of vascular endothelial growth factor (VEGF) and E26 transformation-specific–1 (Ets-1). The authors investigated human carotid plaques to determine whether these hypoxia-inducible angiogenic proteins play a major role in intraplaque angiogenesis and hemorrhage. Methods The expression of HIF-1α, VEGF, and Ets-1 was analyzed using immunohistochemistry and Western blotting in 29 human carotid plaques obtained at carotid endarterectomy. The authors investigated the relationship between plaque characteristics and clinical symptoms. Results A higher incidence of plaque hemorrhage was observed in plaques associated with symptoms than in those without symptoms (p = 0.03). Hypoxia-inducible factor–1α, VEGF, and Ets-1 coexisted in the deep layer of plaque, where angiogenesis was remarkably developed; the expression levels of HIF-1α, VEGF, and Ets-1 were significantly enhanced in the main lesion of the plaque (p < 0.01). Symptomatic plaques showed higher expression of VEGF (p = 0.04) than asymptomatic plaques. Plaques with hemorrhage showed a higher incidence of plaque ulcer (p = 0.001) and higher expression of Ets-1 (p = 0.03) than those without hemorrhage. Moreover, significantly increased expressions of VEGF (p = 0.01) and Ets-1 (p = 0.006) were observed in plaques with not only hemorrhages but also ulcers and severe stenosis. Conclusions The findings in this study suggest that hypoxia-inducible angiogenic proteins in human carotid atherosclerosis promote intraplaque angiogenesis, which can induce plaque hemorrhage and progression.

The Large Area Air Shower (LAAS) group has been performing a network observation of extensive air showers (EAS) by using compact arrays. According to J. Linsley, the primary energy of EAS can be estimated from the spread of the arrival times of EAS particles, even with a small array. A shift register system for clocking the arrival times was installed in an array (OUS1) which is located in Okayama University of Science. Analyzing the OUS1 data, we obtained the primary energies of large air showers.

The compact extensive air shower (EAS) array which consists of 8 scintillation counters, and the solid iron magnet spectrometer (the Okayama muon telescope) have been used to measure energy spectrum of muons in EAS from January 2004 in Okayama University. We compared the result of the muon energy spectrum tagged by EAS trigger signals with EAS simulations which agreed with higher energy hadronic interaction models such as QGSJET and SYBILL, and lower energy hadronic ones such as Hillas Splitting Algorithm, GHEISHA and UrQMD, in order to verify the influence of the hadronic interaction model upon properties of EAS particles, especially the energy spectrum of muons.

We measure the atmospheric muon flux and the charge ratio using the OKAYAMA telescope. It is a solid iron core magnet spectrometer. We report the results of the muon flux and the charge ratio using the maximum likelihood and deconvolution techniques.

The magnetic field effects on DNA electrophoresis have been investigated under the gradient and the homogeneous magnetic fields. The electrophoretic distance of the DNA is different between them. The increase and decrease in the electrophoretic velocity are discovered in the gradient magnetic fields. The acceralation and decceralation of DNA are observed in the negative and positive gradients of the magnetic fields, respectively. The results are discussed with the magnetic force and a new separation method of DNAs is suggested.

The efficacy of individual chemotherapy based on chemosensitivity has scarcely been studied.We examined the chemosensitivites for four anticancer agents - 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3 (2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), carboplatin, cisplatin, and etoposide - of 43 malignant astrocytic tumors (21 anaplastic astrocytomas and 22 glioblastomas) by using a collagen gel matrix assay, and we also determined the survival periods of the tumor-bearing patients. The chemosensitivity was evaluated in terms of the growth inhibition rate, using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) method.For the anaplastic astrocytomas, the mean growth inhibitory rate was 33.2% with cisplatin, 37.2% with carboplatin, 28.0% with ACNU, and 24.8% with etoposide. For the glioblastomas, these rates were 36.9%, 42.3%, 23.2%, and 34.8%, respectively. The median overall and progression-free survivals of anaplastic astrocytoma-bearing patients who had undergone chemotherapy with two anticancer drugs, both of which showed significant anticancer activity (growth inhibitory rate30%) were significantly longer than those of the patients who had been treated with two drugs, one or both of which did not show significant anticancer activity. On the other hand, there was no significant difference in the overall or the progression-free survivals in the two corresponding groups of glioblastoma-bearing patients.The collagen gel matrix assay is clinically useful to determine in vitro chemosensitivity that reflects in vivo chemosensitivity. Individual chemotherapy for malignant astrocytic tumors, based on chemosensitivity data, could contribute to longer survival, particularly in anaplastic astrocytoma-bearing patients.

A 64-year-old man presented with a rare sporadic hemangioblastoma arising in the left optic nerve manifesting as left visual disturbance gradually progressive over 5 years. Magnetic resonance imaging revealed a well-enhanced mass in the left optic nerve. Partial resection of the tumor was performed via the frontoorbital approach. The histological diagnosis was optic nerve hemangioblastoma. Hemangioblastoma must be considered in the differential diagnosis of optic nerve tumors even in the absence of other lesions associated with von Hippel-Lindau disease.

A 27-year-old man presented with a very rare spinal epidural mass associated with recurrence of acute lymphocytic leukemia (ALL) manifesting as acute progressive neurological deficits. The patient presented with shoulder pain and ambulatory difficulties 3 years after remission of ALL treated by bone marrow transplantation. Magnetic resonance imaging revealed an epidural mass extending from C-7 to T-3, which compressed the cord and extended to the intervertebral foramen along the roots. After decompression surgery, the symptoms dramatically improved. Histological examination showed clusters of immature lymphocytes consistent with recurrence of leukemia, so chemotherapy and radiation therapy were carried out. At 1 year after the operation, no local mass expansion or systemic progression of leukemia had occurred. Leukemic mass must be considered in the differential diagnosis of spinal epidural mass, even in patients with ALL.