109 research outputs found
Unruptured Saccular Aneurysm Arising from the Fenestrated A1 Segment of the Anterior Cerebral Artery: Report of 2 Cases
Some cases of aneurysms originating from the fenestrated A1 segment of the anterior cerebral artery (ACA) have been reported, but the pitfalls of the surgical procedure have not been well determined. We herein report 2 cases of a saccular aneurysm arising from the fenestrated A1 segment. Case 1 was a 72-year-old man incidentally diagnosed with an unruptured left ACA aneurysm on magnetic resonance imaging (MRI). Cerebral angiography revealed a saccular aneurysm arising from the proximal end of the left A1 segment. He underwent surgical clipping via the left pterional approach. The aneurysm originated from the proximal bifurcation of the fenestrated left A1 segment. A fenestrated ring clip was applied to obliterate the aneurysmal neck and one small fenestrated trunk, preserving the other fenestrated trunk and perforators around the fenestration. Case 2 was a 73-year-old man incidentally diagnosed with an unruptured ACA aneurysm on MRI. Cerebral angiography revealed a saccular aneurysm arising from the proximal end of the fenestrated left A1 segment. He underwent surgical clipping via the interhemispheric approach. The aneurysm originated from the proximal bifurcation of the fenestrated left A1 segment. A fenestrated ring clip was applied to obliterate the aneurysmal neck and one hypoplastic fenestrated trunk, preserving the other fenestrated trunk and perforators around the aneurysm. Detailed intraoperative evaluations of the anatomical structure and hemodynamics around the fenestration are important. The intentional obliteration of a fenestrated trunk and application of fenestrated clips need to be considered in difficult cases in order to expose the aneurysmal neck
Identification of amino acids in antigen-binding site of class II HLA proteins independently associated with hepatitis B vaccine response
Background & aimsGenetic factors in class II human leukocyte antigen (HLA) have been reported to be associated with inter-individual variation in hepatitis B virus (HBV) vaccine response. However, the mechanism underlying the associations remains elusive. In particular, the broad linkage disequilibrium in HLA region complicates the localization of the independent effects of genetic variants. Thus, the present study aimed to identify the most probable causal variations in class II HLA loci involved in the immune response to HBV vaccine.MethodsWe performed a case-control study to assess whether HLA-DRB1, -DQB1, and -DPB1 4-digit alleles were associated with the response to primary HBV vaccination in 574 healthy Japanese students. To identify causative variants, we next assessed independently associated amino acid variants in these loci using conditional logistic regression analysis. Furthermore, to clarify the functional effects of these variants on HLA proteins, we performed computational structural studies.ResultsHLA-DRB1∗01:01, HLA-DRB1∗08:03, HLA-DQB1∗05:01, and HLA-DPB1∗04:02 were significantly associated with sufficient response, whereas HLA-DPB1∗05:01 was associated with poor response. We then identified amino acids independently associated with sufficient response, namely, leucine at position 26 of HLA-DRβ1 and glycine-glycine-proline-methionine at positions 84–87 of HLA-DPβ1. These amino acids were located in antigen-binding pocket 4 of HLA-DR and pocket 1 of HLA-DP, respectively, which are important structures for selective binding of antigenic peptides. In addition, the detected variations in HLA-DP protein were responsible for the differences in the electrostatic potentials of the pocket, which can explain in part the sufficient/poor vaccine responses.ConclusionHLA-DRβ1 position 26 and HLA-DPβ1 positions 84–87 are independently associated with anti-HBs production against HBV vaccine. Our results suggest that HBsAg presentation through these HLA pocket structures plays an important role in the inter-individual variability of HBV vaccination
Ethylene Glycol Monomethyl Ether–Induced Toxicity Is Mediated through the Inhibition of Flavoprotein Dehydrogenase Enzyme Family
Ethylene glycol monomethyl ether (EGME) is a widely used industrial solvent known to cause adverse effects to human and other mammals. Organs with high metabolism and rapid cell division, such as testes, are especially sensitive to its actions. In order to gain mechanistic understanding of EGME-induced toxicity, an untargeted metabolomic analysis was performed in rats. Male rats were administrated with EGME at 30 and 100 mg/kg/day. At days 1, 4, and 14, serum, urine, liver, and testes were collected for analysis. Testicular injury was observed at day 14 of the 100 mg/kg/day group only. Nearly 1900 metabolites across the four matrices were profiled using liquid chromatography-mass spectrometry/mass spectrometry and gas chromatography-mass spectrometry. Statistical analysis indicated that the most significant metabolic perturbations initiated from the early time points by EGME were the inhibition of choline oxidation, branched-chain amino acid catabolism, and fatty acid β-oxidation pathways, leading to the accumulation of sarcosine, dimethylglycine, and various carnitine- and glycine-conjugated metabolites. Pathway mapping of these altered metabolites revealed that all the disrupted steps were catalyzed by enzymes in the primary flavoprotein dehydrogenase family, suggesting that inhibition of flavoprotein dehydrogenase–catalyzed reactions may represent the mode of action for EGME-induced toxicity. Similar urinary and serum metabolite signatures are known to be the hallmarks of multiple acyl-coenzyme A dehydrogenase deficiency in humans, a genetic disorder because of defects in primary flavoprotein dehydrogenase reactions. We postulate that disruption of key biochemical pathways utilizing flavoprotein dehydrogenases in conjugation with downstream metabolic perturbations collectively result in the EGME-induced tissue damage
Development of a novel artificial intelligence algorithm to detect pulmonary nodules on chest radiography
Background: In this study, we aimed to develop a novel artificial intelligence (AI) algorithm to support pulmonary nodule detection, which will enable physicians to efficiently interpret chest radiographs for lung cancer diagnosis. Methods: We analyzed chest X-ray images obtained from a health examination center in Fukushima and the National Institutes of Health (NIH) Chest X-ray 14 dataset. We categorized these data into two types: type A included both Fukushima and NIH datasets, and type B included only the Fukushima dataset. We also demonstrated pulmonary nodules in the form of a heatmap display on each chest radiograph and calculated the positive probability score as an index value. Results: Our novel AI algorithms had a receiver operating characteristic (ROC) area under the curve (AUC) of 0.74, a sensitivity of 0.75, and a specificity of 0.60 for the type A dataset. For the type B dataset, the respective values were 0.79, 0.72, and 0.74. The algorithms in both the type A and B datasets were superior to the accuracy of radiologists and similar to previous studies. Conclusions: The proprietary AI algorithms had a similar accuracy for interpreting chest radiographs when compared with previous studies and radiologists. Especially, we could train a high quality AI algorithm, even with our small type B data set. However, further studies are needed to improve and further validate the accuracy of our AI algorithm
Comparison of low temperature adaptation ability in three native and two hybrid strains of the rotifer Brachionus plicatilis species complex
The low temperature adaptation ability of five selected strains of the Brachionus plicatilis species complex, i.e., three native strains [ Japanese (NH1L), Australian, German] and two hybrid strains [♀NH1L and ♂Australian (N × A) and ♀NH1L and ♂German (N × G),was investigated in terms of life history traits, reproductive characteristics, and mobility under different thermal conditions (12 and 25 °C). The life history traits of these five strains included a longer lifespan, reproduction period and generation times at 12 °C than at 25 °C, combined with reduced lifetime egg and offspring production. At 12 °C, the intrinsic rate of natural increase was higher in NH1L and N × A strains. Reproductive characteristics determined at 12 °C by batch culture showed active population growth for NH1L and N × G strains, while no resting egg production was observed in all of the strains tested. The ratio of swimming rotifers at 12 °C was monitored every hour for 6 h (short term) and every day for 10 days (long term). In the short-term study there was a 81% ratio of swimming rotifers of the NH1L strain, while other strains exhibited low swimming ratios (75% swimming ratio from the initial day of the study. These results suggest that outcrossing of rotifer strains is useful to obtain live food resources for the larviculture of cold water fish
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