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Yuki Matsumoto Mikiko Kobayashi Kunihiko Shingu Ayako Tateishi Maki Ohya Kenji Sano Tatsuya Negishi Shohei Shigeto Tatsuya Kobayashi Yosuke Hara Yukinari Kakizawa Hiroyuki Kanno 《Neuropathology》2020,40(5):507-514
Pleomorphic xanthoastrocytomas (PXAs) are rare low-grade astrocytic tumors that typically present as superficial nodular cystic tumors of the cerebrum attached to the leptomeninx. Histologically, they are pleomorphic, hypercellular glial neoplasms. Despite the presence of microscopic pleomorphism, patients’ postoperative prognosis is generally good. Anaplastic PXAs (APXAs) have a high mitotic index and patients with APXAs have a worse prognosis than patients with PXAs. Here, we report an autopsy case of APXA initially diagnosed as PXA. After gross total resection, the tumor recurred and was diagnosed as an APXA; thereafter, the patient died. An autopsy revealed that the tumor had relapsed at the primary site and had spread to the leptomeningeal space while concurrently invading the cerebrum including the periventricular area forming multifocal lesions. The histological findings of the autopsy were similar to those for epithelioid glioblastoma (EGBM) and small cell glioblastoma (SCGBM). In particular, the periventricular area with multifocal lesions was composed of SCGBM-like cells. It has been shown that multifocal lesions are frequently identified in patients with SCGBM. This is the first histopathologically confirmed case of APXA-related tumor presenting with periventricular extension and multifocal lesion formation. The periventricular extension might be a feature of PXAs and APXAs. However, suspected periventricular spread on imaging in past cases of PXAs and APXAs might instead represent the malignant transformation of these tumors to glioblastoma-like high-grade tumors, which often show SCGBM-like histological patterns. 相似文献
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Vesicular swelling in the cervical region (VSC) is occasionally observed among human embryos around Carnegie stage (CS) 21. However, its mechanism and significance in fetal development are unclear. The present study aimed to analyze the relation of development of VSC with jugular lymph sac (JLS) formation. Serial histological sections that were digitalized from 14 embryos at CS20 and CS21 stored at the Kyoto Collection were used for the analysis. Subcutaneous edema and enlargement of the subarachnoid space were found to cause VSC. No obvious abnormalities in cranial regions that may be related to the VSC were detected on histological sections. Three-dimensional reconstructions revealed the following: (a) the JLS was located bilaterally at the levels between the first and fourth cervical vertebrae; (b) the JLS was pyramidal in shape; and (c) no severe deformity and/or malformation was found in all samples. The JLS was not connected to the subcutaneous tissue and subarachnoid space in all samples. The mean volume of the JLS increased nine-times from CS20 (0.02 mm3 in VSC [−] group) to CS21 (0.18 mm3 in VSC [−] group). The mean volume of the JLS was comparable between the VSC [−] and VSC (+) groups at both CS20 and CS21. A moderate correlation was observed between VSCd and the mean volume of the JLS in both groups at CS20 (R2 = 0.75) and CS21 (R2 = 0.56). In conclusion, the dynamics of the lymphatic system at the cervical region may contribute to VSC observed around CS21. © 2019 Japanese Teratology Society 相似文献
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Dengue is the most common arboviral infection globally, but its pathogenesis is poorly explored. Vascular endothelial growth factor (VEGF) has an essential role in the host defense against viral infection. However, not much information is available regarding its status in dengue patients from the eastern zone of India. In the present investigation, the level of VEGF was investigated for its possible utility as a dengue severity marker. Accordingly, confirmed dengue cases were enrolled during 2016-2018. Serum from all the study subjects was subjected to the standard enzyme-linked immunosorbent assay test for VEGF analysis. In addition, we assessed the association of VEGF to dengue severity. The study revealed that VEGF titers (P < .0001) were significantly increased in severe dengue (SD) patients in contrast to those with a milder form of dengue. An association was obtained between VEGF and increased SGOT (r = 0.517 with P < .0001) while VEGF had a negative correlation with platelets in SD patients (r = −0.331 with P = .001). Enhanced VEGF titers along with decreased platelets had a good association with SD. The investigation revealed that high VEGF titers are novel indicators of dengue severity. However, our results must be verified in a study evaluating a larger number of dengue patients. 相似文献
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Shimamura Junichi Nishimura Takashi Mizuno Toshihide Takewa Yoshiaki Tsukiya Tomonori Inatomi Ayako Katagiri Nobumasa Ando Masahiko Umeki Akihide Akiyama Daichi Arakawa Mamoru Ono Minoru Tatsumi Eisuke 《Journal of artificial organs》2019,22(4):348-352
Journal of Artificial Organs - The purpose of this study was to observe and clarify the interventricular dysscynchrony caused by continuous-flow left ventricular assist device (CF-LVAD) support... 相似文献