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71.
Akihisa Okumura Masaharu Hayashi Keiko Shimojima Mitsuru Ikeno Tomohisa Uchida Jun‐ichi Takanashi Nobuhiko Okamoto Ken Hisata Hiromichi Shoji Akira Saito Toru Furukawa Tetsuko Kishida Toshiaki Shimizu Toshiyuki Yamamoto 《Neuropathology》2013,33(5):553-560
We report a case of an infant with unique and unreported combinations of brain anomalies. The patient showed distinctive facial findings, severe delay in psychomotor development, cranial nerve palsy and seizures. Brain magnetic resonance imaging performed at 5 days of age revealed complex brain malformations, including heterotopia around the mesial wall of lateral ventricles, dysmorphic cingulate gyrus, and enlarged midbrain tectum. The patient unexpectedly died at 13 months of age. Postmortem pathological findings included a polymicrogyric cingulate cortex, periventricular nodular heterotopia, basal ganglia and thalamic anomalies, and dysmorphic midbrain tectum. Potential candidate genes showed no abnormalities by traditional PCR‐based sequencing. Whole‐exome sequencing confirmed the presence of novel gene variants for filamin B (FLNB), guanylate binding protein family member 6, and chromosome X open reading frame 59, which adapt to the autosomal recessive mode or X‐linked recessive mode. Although immunohistochemical analysis confirmed the expression of FLNB protein in the vessel walls and white matter in autopsied specimens, there may be functional relevance of the compound heterozygous FLNB variants during brain development. 相似文献
72.
Yoshifumi Horie Nobuhiko Kanazawa Chiho Takahashi Norihisa Tatarazako Taisen Iguchi 《Journal of applied toxicology : JAT》2020,40(6):804-814
Bisphenol A (BPA), a very important raw material in the plastics industry, is an endocrine-disrupting chemical in teleost fish. Although BPA induces testis-ova and sex reversal in teleost fish species, the molecular mechanism remains unclear. We evaluated the effects of BPA (measured concentrations: 45, 92, 326, 1030 and 3406 μg/L) on Japanese medaka (Oryzias latipes) using OECD TG234 (2011, Fish Sexual Development Test, OECD Guidelines for the Testing of Chemicals, Section 2). BPA at 1030 and 3406 μg/L induced testis-ova and sex reversal with female-type secondary sexual characteristics in XY males at 30 and 60 days posthatching (dph). Then we examined the BPA effect on the expression of sex differentiation genes related to the testis-ova and sex reversal in XY medaka. BPA exposure (1030 and 3406 μg/L) suppressed gsdf mRNA expression and increased cyp19a1a mRNA expression in XY individuals at stage 38 and 30 dph, although foxl2 mRNA expression showed no change. Interestingly, the concentration of BPA that suppressed gsdf mRNA expression at the larval stage was consistent with that needed to induce testis-ova and sex reversal. These results suggest that the gsdf gene at the embryonic stage can be used as a useful biomarker for predicting the impact of estrogenic endocrine-disrupting chemicals on sexual differentiation in Japanese medaka. 相似文献
73.
Hip range‐of‐motion (ROM) is less than normal after rotational acetabular osteotomy for developmental dysplasia of the hip: A simulated ROM analysis 下载免费PDF全文
Hidetoshi Hamada Masaki Takao Ichiro Nakahara Takashi Sakai Takashi Nishii Nobuhiko Sugano 《Journal of orthopaedic research》2016,34(2):217-223
The optimal reorientation of the acetabulum for developmental dysplasia of the hip (DDH) is unknown in terms of hip range‐of‐motion (ROM). The simulated ROMs of 52 DDHs after rotational acetabular osteotomy (RAO) with several patterns of femoral head coverage and those of 73 normal hips were analyzed using computer models reconstructed from CT images. After RAO with a lateral center edge angle (LCEA) of 30° and an anterior center edge angle (ACEA) of 55° producing coverage similar to that of normal hips, the maximal flexion and maximal internal rotation at 110° flexion with 20° adduction were significantly smaller than those of the normal group. To achieve ROMs after RAO similar to those of the normal group, an LCEA of 30° with an ACEA of 45°, an LCEA of 25° with an ACEA of 45° to 50°, and an LCEA of 20° with an ACEA of 50° could be preferred angles to target, even though they provided smaller coverage than that of normal hips. After RAO producing femoral head coverage similar to that of normal hips, the maximal flexion and the maximal internal rotation at 110° flexion with 20° adduction were significantly smaller than those of the normal group. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:217–223, 2016. 相似文献
74.
Hirano K Kuratani K Fujiyoshi M Tashiro N Hayashi E Kinoshita M 《Neuroscience letters》2007,412(2):159-162
The taiep rat is a myelin mutant in which immobility episodes (IEs) can be induced in adult males by gripping. EEG recordings during gripping-induced IEs show a rapid eye movement (REM) sleep-like pattern, similar to that reported for narcolepsy-cataplexy suggesting that IEs represent a disorder of REM-sleep. An alpha(2) adrenoceptor agonist increases gripping-induced IEs, whereas alpha(2) antagonists decrease these. We have studied the effect of prazosin on IEs and the levels of alpha(1) adrenoceptors were evaluated in cerebro-cortical homogenates of taiep and control rats. Systemic administration of prazosin results in a significant increase in both the frequency and duration of gripping-induced IEs. Our results show that cerebro-cortical tissue is not an adequate candidate for the expression of cataplexy-like symptoms, but prazosin, an alpha(1) antagonist, is a potent inducer of gripping-induced immobility episodes in taiep rats. 相似文献
75.
Lesniak J Tokuda J Kikinis R Burghart C Hata N 《Physics in medicine and biology》2007,52(21):6427-6438
Organ motion compensation in image-guided therapy is an active area of research. However, there has been little research on motion tracking and compensation in magnetic resonance imaging (MRI)-guided therapy. In this paper, we present a method to track a moving organ in MRI and control an active mechanical device for motion compensation. The method proposed is based on MRI navigator echo tracking enhanced by Kalman filtering for noise robustness. We also developed an extrapolation scheme to resolve any discrepancies between tracking and device control sampling rates. The algorithm was tested in a simulation study using a phantom and an active mechanical tool holder. We found that the method is feasible to use in a clinical MRI scanner with sufficient accuracy (0.36 mm to 1.51 mm depending on the range of phantom motion) and is robust to noise. The method proposed may be useful in MRI-guided targeted therapy, such as focused ultrasound therapy for a moving organ. 相似文献
76.
Shimizu Tomofumi Shibuya Nobuhiko Narukawa Yuji Oshima Naohiro Hada Noriyasu Kiuchi Fumiyuki 《Journal of natural medicines》2018,72(1):181-191
Journal of Natural Medicines - Scutellaria root, the root of Scutellaria baicalensis Georgi, is a crude drug used for inflammatory diseases. In our previous report, the combination of flavonoids... 相似文献
77.
78.
79.
Naoyuki Maeda Kanako Okumura Emi Tanaka Tomokazu Suzuki Taku Miyasho Satoko Haeno Hiromi Ueda Nobuhiko Hoshi Hiroshi Yokota 《Environmental toxicology》2014,29(12):1452-1459
Reproductive toxicities and endocrine disruptions caused by chemicals in adult males are still poorly understood. It is our objectives to understand further details of the initial adverse effects leading severe testicular toxicities of a pharmaceutical endocrine disruptor, diethylstilbestrol (DES). Downregulations of both testicular regulatory proteins, such as the steroidogenic acute regulatory protein (StAR) and the peripheral benzodiazepine receptor (PBR), which play important roles in the transport of cholesterol into the mitochondria, and cytochrome P450 mediating the cholesterol side chain cleavage reaction (P450scc), were observed in the rat orally administered DES (340 μg/kg/2 days) for 2 weeks. We found that after only 1 week treatment with DES, the blood and testicular testosterone (TS) levels were drastically decreased without abnormalities of the StAR and PBR; however, the protein and mRNA levels of P450scc were diminished. Decrease in the conversion rate of cholesterol to pregnenolone was delayed in the in vitro assay using the testicular mitochondrial fraction from the rat treated with DES for 1 week. When the precursors in TS biosynthesis containing the testis were identified and determined by liquid chromatography‐mass spectrometry analysis, decreased levels of all precursors except cholesterol were observed. In conclusion, suppressed cytochrome P450scc expression in adult male rat was identified as an initial target of DES in testicular steroidogenesis disorder leading reproductive toxicities. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1452–1459, 2014. 相似文献
80.
Hiroshi Yoshida Tetsuya Shimizu Masato Yoshioka Nobuhiko Taniai 《Hepatology research》2021,51(3):251-262
Portal hypertension is most commonly caused by chronic liver disease. As liver damage progresses, portal pressure gradually elevates and hemodynamics of the portal system gradually change. In normal liver, venous returns from visceral organs join the portal trunk and flow into the liver (hepatopetal blood flow). As portal pressure increases due to liver damage, congestion of some veins of the visceral organ occurs (blood flow to and from). Finally, the direction of some veins (the left gastric vein in particular) of the visceral organ change (hepatofugal blood flow) and develop as collateral veins (portosystemic shunt) to reduce portal pressure. Therefore, esophagogastric varices serve as drainage veins for the portal venous system to reduce the portal pressure. In chronic liver disease, as intrahepatic vascular resistance is increased (backward flow theory) and collateral veins develop, adequate portal hypertension is required to maintain portal flow into the liver through an increase of blood flow into the portal venous system (forward flow theory). Splanchnic and systemic arterial vasodilatations increase the blood flow into the portal venous system (hyperdynamic state) and lead to portal hypertension and collateral formation. Hyperdynamic state, especially around the spleen, is detected in patients with portal hypertension. The spleen is a regulatory organ that maintains portal flow into the liver. In this review, surgical treatment, interventional radiology, endoscopic treatment, and pharmacotherapy for portal hypertension (esophagogastric varices in particular) are described based on the portal hemodynamics using schema. 相似文献