Most Azole-Susceptible Isolates of Aspergillus fumigatus in Hokkaido, Japan are Clustered with Worldwide Strains That Do Not Have Tandem Repeats in Cyp51A Promoter.

In this study, we analyzed Aspergillus fumigatus short tandem repeat patterns of 106 strains isolated from the outdoor air, clinical specimens, and king penguins (Aptenodytes patagonicus) with aspergillosis in Japan, and compared them with those of 668 strains from AfumID (including six isolates from Japan). The results showed that the isolates were classified into three major groups. Group II contained most of the azole-resistant strains with 34- and 46-bp tandem repeats in cyp51A promoter. As in our previous study, OKH50 and Env1 strains were classified in Group II. Most of the azole-susceptible strains obtained in Japan were classified in Group III.

[Detection of Gamma-Ray Irradiation History of Dried Plant-Based Foods via the Analysis of 5,6-Dihydrothymidine].

Irradiation is widely used worldwide to sterilize and kill insects in food, and prevent the germination of agricultural products. However, in Japan, food irradiation is prohibited except to prevent potato sprouting. Herein, 5,6-dihydrothymidine (DHdThd) residue-a damaged nucleoside generated from the thymidine (dThd) residue in DNA contained in food upon irradiation-was used as a detection indicator. Eight dried plant-based food samples were gamma ray-irradiated in the range from 3.2 to 8.3 kGy. Subsequently, DNA was extracted from the irradiated sample and digested into nucleosides by the three enzymes, and the test solution was analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Evidently, in all samples, the concentration ratio of DHdThd to dThd in the test solution (DHdThd/dThd) was dependent on the irradiation dose; moreover, during storage under frozen conditions for at least 890 d post-irradiation, this concentration ratio was equal to that immediately after irradiation. The irradiation histories of the eight types of dried plant-based food samples were correctly detected.

Semi-quantitative evaluation of chest computed tomography for coronavirus disease 2019 in a critical care unit: A case-control study.

The spread of abnormal opacity on chest computed tomography (CT) has been reported as a predictor of coronavirus disease 2019 (COVID-19) severity; however, the relationship between CT findings and prognosis in patients with severe COVID-19 remains unclear. The objective of this study was to evaluate the extent of abnormal opacity on chest CT and its association with prognosis in patients with COVID-19 in a critical care medical center, using a simple semi-quantitative method. This single-center case-control study included patients diagnosed with severe COVID-19 pneumonia who were admitted to a critical care center. The diagnosis of COVID-19 was based on positive results of a reverse transcription polymerase chain reaction test. All patients underwent non-contrast whole-body CT upon admission. Six representative axial chest CT images were selected for each patient to evaluate the extent of lung lesions. The percentage of the area involved in the representative CT images was visually assessed by 2 radiologists and scored on 4-point scale to obtain the bedside CT score, which was compared between patients who survived and those who died using the Mann-Whitney U test. A total of 63 patients were included in this study: 51 survived and 12 died after intensive treatment. The inter-rater reliability of bedside scores between the 2 radiologists was acceptable. The median bedside CT score of the survival group was 12.5 and that of the mortality group was 16.5; the difference between the 2 groups was statistically significant. The degree of opacity can be easily scored using representative CT images in patients with severe COVID-19 pneumonia, without sophisticated software. A greater extent of abnormal opacity is associated with poorer prognosis. Predicting the prognosis of patients with severe COVID-19 could facilitate prompt and appropriate treatment.

Use of intravascular hypo- and hyper-attenuation on non-contrast-enhanced computed tomography in diagnosing acute septic thrombophlebitis.

Septic thrombi, such as those observed in pylephlebitis and Lemierre's syndrome, are characterized by portal vein thrombosis and venous thrombosis with bacterial infection. Although radiographic findings of septic thrombus on contrast-enhanced computed tomography have been well described, no report has described the characteristics of non-contrast-enhanced computed tomography. We describe a case series of septic thrombophlebitis exhibiting intravascular hypo- and hyper-attenuation on non-contrast-enhanced computed tomography. These radiographic features reflect the pathophysiology of septic thrombus, and therefore, it is important and useful to evaluate thrombus attenuation on non-contrast-enhanced computed tomography.

[Validation Study on an Improved Quantitative Method for Aflatoxins in Foods].

As an analytical method for aflatoxins in foods, the analytical method based on the notification by the director of the Food Safety Department, Pharmaceutical and Food Safety Bureau, Ministry of Health, Labour and Welfare (August 16, 2011) has been established. In order to improve the operability and analytical performance of the conventional method, this study aimed to construct an improved method that optimized selection of immunoaffinity column (IAC) and purifying condition, and omitted evaporation after the purification with IAC. In the recovery test performed by adding 2.5 ng/g of aflatoxin B1, B2, G1 and G2 standard solutions into 9 kinds of food samples, the improved method achieved the established target values: 77.0-99.7% of recovery, 1.7-5.6% of intra-assay coefficient of validation, and 0.9-3.6% of inter-assay of coefficient of variation, respectively. The improved method also achieved 4.3-10.5% greater recovery and 1.5 hours shorter preparation time than the conventional one. These results indicate applicability of the improved method for 9 kinds of foods and its efficacy as an analytical method for aflatoxins in foods.

Exteriorization of Petrous Bone Cholesteatoma by Endonasal Endoscopic Approach: A Case Report.

A 61-year-old woman presented with diplopia and headache. The patient had a longstanding history of petrous bone cholesteatoma (PBC) on the left side and had undergone multiple surgeries to address it. Computed tomography (CT) revealed a radiolucent lesion with bony destruction in the left petrous apex. Magnetic resonance imaging of the lesion revealed a hypointense area on T1-weighted images and a hyperintense area on T2-weighted and abnormal diffusion-weighted images. A diagnosis of recurrent petrous apex cholesteatoma was made. The patient was treated by exteriorization using an endoscopic endonasal approach. The patient is in remission and doing well. The ideal treatment of PBC is complete excision, though exteriorization using an endoscopic endonasal approach is considered a second option when excision is not possible.

MRI imaging features of HIV-related central nervous system diseases: diagnosis by pattern recognition in daily practice.

With the advent of antiretroviral therapy (ART), the prognosis of people infected with human immunodeficiency virus (HIV) has improved, and the frequency of HIV-related central nervous system (CNS) diseases has decreased. Nevertheless, mortality from HIV-related CNS diseases, including those associated with ART (e.g., immune reconstitution inflammatory syndrome) remains significant. Magnetic resonance imaging (MRI) can improve the outlook for people with HIV through early diagnosis and prompt treatment. For example, HIV encephalopathy shows a diffuse bilateral pattern, whereas progressive multifocal leukoencephalopathy, HIV-related primary CNS lymphoma, and CNS toxoplasmosis show focal patterns on MRI. Among the other diseases caused by opportunistic infections, CNS cryptococcosis and CNS tuberculosis have extremely poor prognoses unless diagnosed early. Immune reconstitution inflammatory syndrome shows distinct MRI findings from the offending opportunistic infections. Although distinguishing between HIV-related CNS diseases based on imaging alone is difficult, in this review, we discuss how pattern recognition approaches can contribute to their early differentiation.

Quantification of Intracellular Thiols by HPLC-Fluorescence Detection.

Biothiols, such as cysteine and glutathione, play important roles in various intracellular reactions represented by the redox equilibrium against oxidative stress. In this study, a method for intracellular thiol quantification using HPLC-fluorescence detection was developed. Thiols were derivatized with a thiol-specific fluorescence derivatization reagent, viz. ammonium 7-fluoro-2,1,3-benzoxadiazole-4-sulfonate (SBD-F), followed by reversed-phase separation on an InertSustain AQ-C18 column. Six different SBD-thiols (homocysteine, cysteine, cysteinylglycine, γ-glutamylcysteine, glutathione, and N-acetylcysteine as an internal standard) were separated within 30 min using a citric buffer (pH 3.0)/MeOH mobile phase. The calibration curves of all the SBD-thiols had strong linearity (R2 > 0.999). Using this developed method, the thiol concentrations of human chronic myelogenous leukemia K562 cell samples were found to be 5.5-153 pmol/1 × 106 cells. The time-dependent effect of a thiol scavenger, viz. N-ethyl maleimide, on intracellular thiol concentrations was also quantified. This method is useful for elucidating the role of intracellular sulfur metabolism.

Fast analysis using pillar array columns: Quantification of branched-chain α-keto acids in human plasma samples.

Branched-chain α-keto acids (BCKAs, namely, α-ketoisovaleric acid (KIV), α-ketoisocaproic acid (KIC), and α-keto-ß-methylvaleric acid (KMV)) are related to many diseases such as myeloid leukemia, liver cancer, and diabetes mellitus. A rapid quantitative analytical method for BCKAs using pillar array columns was developed. α-Keto acids were labeled with 1,2-diamino-4,5-methylenedioxybenzene (DMB), followed by their separation on octadecylsilane-treated pillar array columns with MeOH/H2O as the mobile phase. Five DMB-labelled α-keto acids including the internal standard were separated in 160 s. The lower limits of quantification for DMB-α-keto acids were 2-5 µM. The intra- and interday precisions were 2.9-6.6 % and 5.2-10.7 %, respectively. The developed method was applied to BCKA quantification in human plasma samples; KIV, KIC, and KMV concentrations were determined to be 13.8, 24.2, and 15.2 µM, respectively. The method realized rapid, sensitive, and precise analysis of BCKAs and can be applied for clinical diagnosis.

Improvement of the diagnostic accuracy for intracranial haemorrhage using deep learning-based computer-assisted detection.

PURPOSE: To elucidate the effect of deep learning-based computer-assisted detection (CAD) on the performance of different-level physicians in detecting intracranial haemorrhage using CT. METHODS: A total of 40 head CT datasets (normal, 16; haemorrhagic, 24) were evaluated by 15 physicians (5 board-certificated radiologists, 5 radiology residents, and 5 medical interns). The physicians attended 2 reading sessions without and with CAD. All physicians annotated the haemorrhagic regions with a degree of confidence, and the reading time was recorded in each case. Our CAD system was developed using 433 patients' head CT images (normal, 203; haemorrhagic, 230), and haemorrhage rates were displayed as corresponding probability heat maps using U-Net and a machine learning-based false-positive removal method. Sensitivity, specificity, accuracy, and figure of merit (FOM) were calculated based on the annotations and confidence levels. RESULTS: In patient-based evaluation, the mean accuracy of all physicians significantly increased from 83.7 to 89.7% (p < 0.001) after using CAD. Additionally, accuracies of board-certificated radiologists, radiology residents, and interns were 92.5, 82.5, and 76.0% without CAD and 97.5, 90.5, and 81.0% with CAD, respectively. The mean FOM of all physicians increased from 0.78 to 0.82 (p = 0.004) after using CAD. The reading time was significantly lower when CAD (43 s) was used than when it was not (68 s, p < 0.001) for all physicians. CONCLUSION: The CAD system developed using deep learning significantly improved the diagnostic performance and reduced the reading time among all physicians in detecting intracranial haemorrhage.

Liquid-Chromatographic Methods for Carboxylic Acids in Biological Samples.

Carboxyl-bearing low-molecular-weight compounds such as keto acids, fatty acids, and other organic acids are involved in a myriad of metabolic pathways owing to their high polarity and solubility in biological fluids. Various disease areas such as cancer, myeloid leukemia, heart disease, liver disease, and lifestyle diseases (obesity and diabetes) were found to be related to certain metabolic pathways and changes in the concentrations of the compounds involved in those pathways. Therefore, the quantification of such compounds provides useful information pertaining to diagnosis, pathological conditions, and disease mechanisms, spurring the development of numerous analytical methods for this purpose. This review article addresses analytical methods for the quantification of carboxylic acids, which were classified into fatty acids, tricarboxylic acid cycle and glycolysis-related compounds, amino acid metabolites, perfluorinated carboxylic acids, α-keto acids and their metabolites, thiazole-containing carboxylic acids, and miscellaneous, in biological samples from 2000 to date. Methods involving liquid chromatography coupled with ultraviolet, fluorescence, mass spectrometry, and electrochemical detection were summarized.

Analysis of intracellular α-keto acids by HPLC with fluorescence detection.

Branched-chain keto acids and branched-chain amino acids are metabolites of branched-chain amino acid aminotransferases (BCATs), which catalyzes reversible transamination between them. We found that BCAT1 plays an important role in the progression of myeloid leukaemia, and a method for the analysis of intracellular α-keto acids including branched-chain keto acids was necessary to further investigate their role. In this study, we developed a method to analyze six α-keto acids (α-ketoglutaric acid (KG), pyruvic acid, α-ketobutyric acid, α-ketoisovaleric acid, α-ketoisocaproic acid, and α-keto-ß-methylvaleric acid) in K562 cells by HPLC with fluorescence detection, using 1,2-diamino-4,5-methylenedioxybenzene (DMB) as a derivatization reagent. Because split peaks of DMB-KG were observed when injection samples were too acidic, the derivatization solution was diluted with NaOH solution to obtain a single peak. Limits of detection and limits of quantification were 1.3-5.4 nM and 4.2-18 nM, respectively. Intracellular concentrations of α-keto acids were 1.55-316 pmol/1 × 106 K562 cells. The developed method realized reproducible and sensitive analysis of intracellular α-keto acids. Thus, the method could be used to elucidate the role of BCAT in myeloid leukaemia.

Silent susceptibility-weighted angiography to detect hemorrhagic lesions in the brain: a clinical and phantom study.

PURPOSE: To compare the effectiveness of silent susceptibility-weighted angiography (sSWAN), a new imaging technique with lower acoustic noise, with conventional susceptibility-weighted angiography (cSWAN) in the detection of intracranial hemorrhagic lesions. METHODS: We measured the acoustic and background noise during sSWAN and cSWAN imaging and calculated the contrast-to-noise ratio (CNR) of the phantom consisting of eight chambers with different concentrations of superparamagnetic iron oxide. In the clinical study, we calculated the CNRs of hemorrhagic lesions in 15 patients and evaluated the images for conspicuity and artifact on each sequence and scored them on a 4-point scale. We also evaluated whether hypointense areas observed on sSWAN or cSWAN increased in size from those on T2*-weighted imaging (T2*-WI). RESULTS: Acoustic noise for sSWAN (57.9 ± 0.32 dB [background noise 51.3 dB]) was significantly less than that for cSWAN (89.0 ± 0.22 dB [background noise 50.9 dB]). The CNRs of phantoms for sSWAN were slightly but not significantly lower than those for cSWAN (P = 0.18). The CNRs of hemorrhagic lesions did not show significant differences between sSWAN and cSWAN (P = 0.17). There were no significant differences between sSWAN and cSWAN with respect to the scores for conspicuity, artifact, and change in size of hypointense areas from T2*-WI. CONCLUSION: sSWAN is equivalent to cSWAN with respect to the image quality for the detection of hemorrhagic lesions but has lower acoustic noise.

Concentrations of total mercury and methylmercury in red snow crabs (Chionoecetes japonicus) caught off the coast of Japan.

The total mercury (T-Hg) and methylmercury (MeHg) concentrations in red snow crabs (Chionoecetes japonicus) caught off the coast of Japan were analyzed. The T-Hg concentration ranged from 0.03 to 0.56 mg/kg (mean: 0.21 mg/kg) in the raw muscle, and 0.02 to 0.74 mg/kg (mean: 0.27 mg/kg) in the boiled muscle. The MeHg concentration ranged from 0.04 to 0.54 mg/kg (mean: 0.20 mg/kg) in the raw muscle. The mean ratio of MeHg to T-Hg was 0.88. The crab body weight was found to significantly correlate with the concentrations of T-Hg (r = 0.488) and MeHg (r = 0.490) (p ≤ 0.01). For the general population in Japan, the intake of MeHg from eating red snow crab was estimated to be lower than 0.013 mg/week, which was less than one-sixth of the tolerable MeHg intake (0.08 mg/week).

Changes in masseter muscle fibers by liquid diet rearing in rabbits and recovery by chewing of solid diet.

OBJECTIVE: To investigate the effects of liquid diet on the development of masseter muscle fibers and whether the changes in the masseter muscle can be recovered by chewing of solid diet. DESIGN: Masseter muscles from 40 rabbits (solid- and liquid-diet groups, n = 30; unweaned group, n = 5; recovery group, n = 5) were histochemically examined at 4, 12, 18, and 33 weeks after birth. Six fiber types (I, IC, IIC, IIA, IIAB, and IIB) were distinguished via mATPase staining. Muscle fiber diameter and fiber type composition were measured and compared between groups. RESULTS: In the liquid diet group, the diameter of types IIAB (solid group: 81.7 µm, liquid group: 60.9 µm) and IIB (solid group: 89.3 µm, liquid group: 68.8 µm) and the fiber type composition of type I (solid group: 18.4%, liquid group: 9.6%) decreased significantly at 33 weeks of age. In the recovery group, the fiber type composition of type I fibers recovered to 16.5%, while no recovery of type IIAB (56.6 µm) and IIB (64.6 µm) fiber diameter was observed. CONCLUSIONS: Liquid diet caused atrophy of muscle fibers and an increase in the proportion of fast-twitch fibers. Although the diameter and ratio of slow-twitch fibers were recovered by chewing of solid diet, recovery was not observed for fast-twitch fibers. Our findings are relevant for dental medicine as it explored the possibility of masticatory muscle function recovery by hard food.

Quantitative susceptibility mapping (QSM) evaluation of infantile neuroaxonal dystrophy.

We present the first case of twins with infantile neuroaxonal dystrophy evaluating brain iron deposition using quantitative susceptibility mapping (QSM). A 6-year-old boy who was normal at birth had psychomotor regression and hypotonia from 2-years-old. Brain MRI showed low intensity areas in globus pallidus (GP) and substantia nigra (SN) on T 2* weighted imaging. QSM values of GP and SN were 0.19 and 0.29 ppm, respectively. His twin brother showed almost the same imaging findings. Follow-up MRI revealed increase of QSM value in GP and SN.

Estimation of Irradiation Doses of Raw Beef Liver Samples using 5,6-Dihydrothymidine as an Irradiation Marker.

The quantities of (5S)- and (5R)-5,6-dihydrothymidine (total DHdThd) in frozen beef liver samples were compared between those irradiated by an electron beam (EB) and those subjected to γ-irradiation. DNA extracted from the samples was enzymatically digested to nucleosides and analyzed by liquid chromatography-tandem mass spectrometry for total DHdThd and 2'-deoxythymidine (dThd). Total DHdThd was formed radiospecifically and dose-dependently and the dose-response curves of the ratio of total DHdThd to dThd (total DHdThd/dThd) were similar for both the EB- and γ-irradiated samples. The total DHdThd/dThd was stable after long-term storage (4 months) at -20 °C and the followed heat treatment in a microwave oven. The total DHdThd/dThd could be a robust marker and is equally effective at quantitating both EB- and γ-ray irradiation history. The irradiation doses of raw beef liver samples were estimated using the dose-response curves of the total DHdThd/dThd of other irradiated samples. The ratio of the estimated dose to the actual dose was 0.74-1.30 in the irradiation range of 4.67-7.62 kGy.

Trichostatin A modulates cellular metabolism in renal cell carcinoma to enhance sunitinib sensitivity.

Although sunitinib is the first-line drug for progressive renal cell carcinoma (RCC), most patients experience its tolerance. One possible way of overcoming drug resistance is combination therapy. Epigenetic modifier is one of the candidate drug group. A recent evidence suggests that cell metabolism is regulated by epigenetic mechanisms. Epigenetic abnormalities lead to changes in metabolism and may contribute to drug resistance and progression of RCC. Consequently, we investigated whether trichostatin A (TSA), a potent histone-deacetylase (HDAC) inhibitor, alters sunitinib-induced cytotoxicity and metabolism in RCC cells at epigenetic regulatory concentrations. Combined metabolome and transcriptome analysis suggested that TSA impacts on energy productive metabolic pathways, such as those involving TCA cycle and nucleotide metabolism especially for increase of hyperphosphorylated form. Combination of sunitinib and TSA increased cell death with PARP cleavage, an early marker of mitochondrial apoptosis, whereas receptor tyrosine kinase signaling, which is the target of sunitinib, was not altered by TSA. Finally, the established sunitinib resistant-RCC cell (786-O Res) was also exposed to sunitinib and TSA combination, resulting in significant growth inhibition. In summary, it was suggested that TSA reduces sunitinib resistance by triggering intracellular metabolome shifts regarding energy metabolism, that is the first recognized mechanism as an HDAC inhibitor.

Multiple blood flow measurements before and after carotid artery stenting via phase-contrast magnetic resonance imaging: An observational study.

After carotid artery stenting, the procurement of information about blood flow redistribution among brain-feeding arteries and its time trend is essential to understanding a patient's physiological background and to determine their care regimen. Cerebral blood flow has been measured twice following carotid artery stenting in few previous studies, with some discrepancies in the results. The purpose of this study was to measure cerebral blood flow at multiple time points after carotid artery stenting, and to elucidate the time trend of cerebral blood flow and redistribution among arteries. Blood flow rates in 11 subjects were measured preoperatively, at one day, one week, and about three months, respectively after carotid artery stenting by using phase-contrast magnetic resonance imaging. The target vessels were the bilateral internal carotid arteries, the basilar artery, and the bilateral middle cerebral arteries. Lumen was semi-automatically defined using an algorithm utilizing pulsatility. The results showed that blood flow rates in the stented internal carotid artery and the ipsilateral middle cerebral artery increased following carotid artery stenting. Blood flow rates in the contralateral internal carotid artery and the basilar artery gradually declined, and they were lower than the preoperative values at three months after stenting. The sum of blood flow rates of the bilateral internal carotid arteries and the basilar artery increased after carotid artery stenting, and then decreased over the next three months. There was no significant change in the blood flow rate in the contralateral middle cerebral artery. From these results, it was concluded that redistribution among the bilateral internal carotid arteries and the basilar artery occurs after carotid artery stenting, and that it takes months thereafter to reach another equilibrium.

Comparative study of pulsed-continuous arterial spin labeling and dynamic susceptibility contrast imaging by histogram analysis in evaluation of glial tumors.

PURPOSE: Arterial spin labeling (ASL) is a non-invasive perfusion technique that may be an alternative to dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) for assessment of brain tumors. To our knowledge, there have been no reports on histogram analysis of ASL. The purpose of this study was to determine whether ASL is comparable with DSC-MRI in terms of differentiating high-grade and low-grade gliomas by evaluating the histogram analysis of cerebral blood flow (CBF) in the entire tumor. METHODS: Thirty-four patients with pathologically proven glioma underwent ASL and DSC-MRI. High-signal areas on contrast-enhanced T1-weighted images or high-intensity areas on fluid-attenuated inversion recovery images were designated as the volumes of interest (VOIs). ASL-CBF, DSC-CBF, and DSC-cerebral blood volume maps were constructed and co-registered to the VOI. Perfusion histogram analyses of the whole VOI and statistical analyses were performed to compare the ASL and DSC images. RESULTS: There was no significant difference in the mean values for any of the histogram metrics in both of the low-grade gliomas (n = 15) and the high-grade gliomas (n = 19). Strong correlations were seen in the 75th percentile, mean, median, and standard deviation values between the ASL and DSC images. The area under the curve values tended to be greater for the DSC images than for the ASL images. CONCLUSIONS: DSC-MRI is superior to ASL for distinguishing high-grade from low-grade glioma. ASL could be an alternative evaluation method when DSC-MRI cannot be used, e.g., in patients with renal failure, those in whom repeated examination is required, and in children.