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51.
Munekazu Naito Shuichi Hirai Hayato Terayama Ning Qu Shogo Hayashi Naoyuki Hatayama Hideto Kawamura Takashi Nakano Masahiro Itoh 《Medical molecular morphology》2014,47(1):21-30
Neonatal estrogen treatment (NET) induces morphological changes in male reproductive organs. NET with β-estradiol 17-cypionate is reported to induce inflammation with stromal-epithelial abnormalities in the prostate and seminal vesicles in post-pubertal mice. The aim of this study was to investigate the histopathology of the testis, ductuli efferentes, epididymis, and vas deferens in mice after NET with β-estradiol 17-cypionate. No morphological changes in these organs were observed until 4 weeks after NET. However, some inflammatory cells were found in epididymis and vas deferens 6 weeks after NET. Eight weeks after NET, inflammatory cells spread to the ductuli efferentes and inflammation was severe from 6 to 12 weeks after NET. Inflammatory cells were never seen in the whole testis, but cystic dilatation of the rete testes with spermatogenic disturbance was found around the mediastinum testis. Many inflammatory cells emigrated into the lumen of the epididymis, resulting in complete absence of spermatozoa in the vas deferens. Most of the inflammatory cells penetrating into the epithelial layers of epididymal ducts were neutrophils. These results indicate that in post-pubertal mice, NET with β-estradiol 17-cypionate induces inflammation in the ductuli efferentes, epididymis, and vas deferens, but not in the testis, provoking obstructive azoospermia. 相似文献
52.
Akane Yu Hayato Niiyama Shinya Kondo Akiko Yamamoto Ryusuke Suzuki 《Journal of biomaterials science. Polymer edition》2013,24(8):1015-1026
We developed a novel wound dressing composed of a hyaluronic acid (HA) and collagen (Col) spongy sheet containing epidermal growth factor (EGF) or basic fibrolast growth factor (bFGF) by freeze-drying method (EGF-wound dressing or bFGF-wound dressing, respectively). A wound dressing without any growth factor was prepared as a control in a similar manner as above (C-wound dressing). Intermolecular cross-linkage between Col molecules was induced by UV irradiation. The release behavior of free HA from the wound dressing was investigated using a C-wound dressing. The weight of C-wound dressing after 1 day, 3, 5, and 7?days of incubation on top of a Col gel sheet at the air–water interface (wound surface model) was 55, 36, 30, and 19% of the original weight, respectively. Most free HA and a part of Col was released from the cross-linked Col network in the wound dressing during incubation, as the original Col content in the wound dressing was 33%. Next, fibroblast proliferation was assessed in conventional culture medium preconditioned by immersion of a piece of C-, EGF-, or bFGF-wound dressing, i.e. C-conditioned medium, EGF-conditioned medium, or bFGF-conditioned medium. Cell proliferation in C-conditioned medium increased to approximately the same level as that in conventional medium. Cell proliferation in EGF- and bFGF-conditioned medium was 1.9 times and 2.6 times greater than that in conventional medium after 7?days of cultivation, respectively. Finally, cytokine production of fibroblasts was assessed in a wound surface model using a fibroblast-incorporating Col gel sheet (cultured dermal substitute [CDS]). CDS was elevated to the air–medium interface, on which each wound dressing was placed and cultured for 7?days. Fibroblasts in CDS covered with EGF-wound dressing released 3.6 times more vascular endothelial growth factor (VEGF) and 4.6 times more hepatocyte growth factor (HGF) when compared with the C-wound dressing. Fibroblasts in CDS covered with bFGF-wound dressing released 10.2 times more VEGF and 6.3 times more HGF when compared with the C-wound dressing. This finding indicates that bFGF-wound dressing can facilitate more effectively the VEGF and FGF production compared with EGF-wound dressing. 相似文献
53.
Shin‐ichi Nakatsuka M.D Ph.D Teruaki Nagano M.D Hayato Kimura M.D Ph.D Tadasuke Nagatomo C.T Yuriko Urase M.T Koji Hashimoto M.D Ph.D 《Diagnostic cytopathology》2013,41(1):67-70
The patient is a 75‐year‐old man with axillary lymphadenopathy presenting an indurated papule on his buttock. Touch imprint cytology of the biopsied axillary lymph node revealed the monotonous appearance of medium‐sized tumor cells. The nuclei had a slightly irregular contour, finely dispersed chromatin, and a conspicuous nucleolus. Some tumor cells had intracytoplasmic microvacuoles. Immunohistochemistry of the imprint specimens showed that the tumor cells were positive for CD56 and CD123. Histological diagnosis of the lesion was blastic plasmacytoid dendritic cell neoplasm (BPDCN). Epstein‐Barr virus‐encoded RNAs were not detected in the tumor cells. Neither immunoglobulin heavy chain genes nor T‐ cell receptor genes was clonally rearranged. BPDCN should be strongly considered during the differential diagnosis of CD56‐positive neoplasms of the skin. We demonstrated a possible contribution of the cytomorphological and immunohistochemical findings of the touch imprint specimens to the diagnosis of BPDCN. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc. 相似文献
54.
Yoshihito Uchida Masamitsu Nakao Shohei Tsuji Hayato Uemura Jun-ichi Kouyama Kayoko Naiki Daisuke Motoya Kayoko Sugawara Nobuaki Nakayama Yukinori Imai Tomoaki Tomiya Satoshi Mochida 《Journal of medical virology》2020,92(3):329-338
The significance of switching of the nucleos(t)ide analog used to treat patients with hepatitis B virus (HBV) from entecavir (ETV) to tenofovir alafenamide fumarate (TAF) is uncertain. The subjects of this study were 159 patients with HBV who received treatment with ETV followed by TAF. Among these patients, serial changes in the HBV marker levels were monitored in 92 patients in whom the serum HBsAg levels were ≥100 IU/mL during the 48-week period immediately before and after the switching. A questionnaire survey for medication compliance was performed in 127 patients. The serum HBsAg levels (log IU/mL) decreased by 0.041 during the ETV treatment period and by 0.068 during the TAF administration period. The degree of reduction was higher during the TAF administration period than during the ETV administration period in patients without cirrhosis (P = .030), patients with genotype B HBV (P = .014), and patients with undetectable serum HBcrAg (P = .038). Multivariate analysis revealed the HBV genotype (B vs C; odds ratio, 3.400; P = .025) and serum aspartate aminotransferase level (every 1+; 1.111; P = .015) at the time of switching as factors influencing the treatment efficacy. Thirty-six patients (28%) responded that the number of days that they forgot to take the drug decreased after the drug switching, and 77 patients (61%) reported feeling satisfied with the drug switching. Switching of the nucleos(t)ide analog used from ETV to TAF may be useful in the treatment of patients with HBV infection, as it is associated with both a decrease in the serum HBsAg level and improvement of the medication compliance. 相似文献
55.
Production and release of infectious hepatitis C virus from human liver cell cultures in the three-dimensional radial-flow bioreactor 总被引:5,自引:0,他引:5
Aizaki H Nagamori S Matsuda M Kawakami H Hashimoto O Ishiko H Kawada M Matsuura T Hasumura S Matsuura Y Suzuki T Miyamura T 《Virology》2003,314(1):16-25
Lack of efficient culture systems for hepatitis C virus (HCV) has been a major obstacle in HCV research. Human liver cells grown in a three-dimensional radial-flow bioreactor were successfully infected following inoculation with plasma from an HCV carrier. Subsequent detection of increased HCV RNA suggested viral replication. Furthermore, transfection of HCV RNA transcribed from full-length cDNA also resulted in the production and release of HCV virions into supernatant. Infectivity was shown by successful secondary passage to a new culture. Introduction of mutations in RNA helicase and polymerase regions of HCV cDNA abolished virus replication, indicating that reverse genetics of this system is possible. The ability to replicate and detect the extracellular release of HCV might provide clues with regard to the persistent nature of HCV infection. It will also accelerate research into the pathogenicity of HCV, as well as the development of prophylactic agents and new therapy. 相似文献
56.
Fumi Tashiro Masami Kanai‐Azuma Satsuki Miyazaki Masahiro Kato Tomofumi Tanaka Shuichi Toyoda Eiji Yamato Hayato Kawakami Tatsushi Miyazaki Jun‐Ichi Miyazaki 《Genes to cells : devoted to molecular & cellular mechanisms》2010,15(8):813-828
In a search for genes specifically expressed in mouse embryonic stem cells, we identified one we called Ces5. We found that it corresponded to the Ooep gene, which was recently reported to be expressed specifically in oocytes. Mouse Ces5/Ooep, also called Moep19 or Floped, encoded a 164‐amino acid protein, which was detected in the cytoplasm of developing and mature oocytes and in embryos throughout the preimplantation period. To examine its function, we carried out targeted disruption of this gene. The Ces5/Ooep‐null mice were grossly normal, but the females were infertile. Although the ovaries and ovulation appeared normal, the embryos from Ces5/Ooep‐null females mated with wild‐type males showed developmental arrest at the two‐ or four‐cell stage. In addition, their first cleavage was considerably delayed and often asymmetrical. Thus, Ces5/Ooep is a maternal‐effect gene. By electron microscopy, we found that the eggs from Ces5/Ooep‐null females lacked oocyte cytoplasmic lattices (CPLs), which have long been predicted to function as a storage form for components that are maternally contributed to the early embryo. Further analysis showed that CES5/OOEP was directly associated with the CPLs. These results indicate that CES5/OOEP is an essential component of the CPLs and is required for embryonic development at the maternal‐zygotic stage transition. 相似文献
57.
Suzuki S Matsui T Imuta H Uenoyama M Yura H Ishihara M Kawakami M 《Medical & biological engineering & computing》2008,46(7):709-714
We developed a novel method for non-contact monitoring of stress-induced autonomic activation through the back of a chair, using a compact 24 GHz microwave radar (8 x 5 x 3 cm), without large-scale equipment and placing a heavy burden on the monitored individual. Following a silent period of 120 s, audio stimuli using a composite tone of 2,120 and 2,130 Hz sine-waves at 95 dB were conducted for 120 s. From dorsal, LF/HF of HRV reflecting sympatho-vagal balance was determined by microwave radar with the maximum entropy method using eight volunteers (mean age 23 +/- 1 years). Mean LF/HF measured by non-contact and contact (using electrocardiography for reference) methods during audio stimuli increased 34 and 37%, respectively, as compared with those of the silent period. Maximum cross-correlations between contact and non-contact measurements averaged 0.73 +/- 0.10. Our method appears to be promising for future monitoring of stress-induced autonomic activation of operators and may reduce stress-induced accidents. 相似文献
58.
Anti‐inflammatory effect of enzymatic hydrolysate of corn gluten in an experimental model of colitis
Miyako Mochizuki Hayato Shigemura Noboru Hasegawa 《The Journal of pharmacy and pharmacology》2010,62(3):389-392
Objectives Intestinal bacteria are thought to be involved in the initiation and perpetuation of inflammatory bowel diseases. Prebiotics (non‐digestable dietary carbohydrate) have beneficial properties that alter the intestinal flora and contain glutamine‐rich protein. Glutamine significantly decreases indices of inflammation. In this study, an enzymatic hydrolysate of corn gluten (EHCG) was administered by gavage to Sprague‐Dawley rats fed an elemental diet to determine whether EHCG can ameliorate experi‐ mental colitis. Methods Colitis was induced by intrarectal administration of 2,4,6‐trinitrobenzene sulfonic acid after 10 days' daily oral administration of EHCG at 100 and 300 mg/kg. Macroscopic damage was assessed using a scoring system. The mucosa homogenate was sonicated and myeloperoxidase activity and histamine levels measured. Key findings Treatment with EHCG significantly decreased the severity of injury and reduced myeloperoxidase activity and histamine levels in the distal colon mucosa. Conclusions EHCG may have therapeutic benefit as a supplement in enteral nutrition for patients with inflammatory bowel diseases. 相似文献
59.
Masayuki Yokoyama Hayato Anazawa Akeo Takahashi Shohei Inoue Kazunori Kataoka Nobuhiko Yui Yasuhisa Sakurai 《Macromolecular chemistry and physics.》1990,191(2):301-311
Novel segmented multiblock copolymers ( 7 ) were synthesized by linking poly(ethylene oxide) (PEO) blocks with poly(β-benzyl L -aspartate)(PBLA) blocks via urethane and urea bonds, which were formed by the reaction of 4,4′-methylenediphenyl isocyanate ( 5 ) with the terminal hydroxyl groups of α-hydro-ω-hydroxypoly(oxyethylene) ( 4 ) and the terminal amino groups of poly(β-benzyl L -aspartate)-block-iminohexamethyleneimino-block-poly(β-benzyl L -aspartate) ( 3 ) [prepared from 1,6-hexanediamine ( 1 ) and β-benzyl L -aspartate N-carboxy anhydride ( 2 )], respectively. Membranes with various water contents were obtained from these copolymers by changing the lengths of the PEO and PBLA segments. The study of the permeation of 1-phenyl-1,2-ethanediol, vitamin B12 and myoglobin through the membranes showed a high dependency of the permeability on the molecular weight of the solutes. 相似文献
60.
We report a case of neuromyelitis optica (NMO) with an unusual pattern of remyelination in the spinal cord. A Japanese woman complained of pain and numbness in the left thumb at the age of 36 years. She mainly presented with optic and spinal symptoms and was initially diagnosed as multiple sclerosis (MS). Her bilateral eyesight decreased, which led to light perception only in the right eye. She became unable to walk without a wheelchair. In spite of steroid pulse therapy, plasma exchange therapy and immunosuppressive therapy, her symptoms gradually worsened. After 33 years of a relapsing–remitting course, she died of septic urinary tract infection at the age of 69 years. Autopsy revealed prominent demyelination in the optic tract and the spinal cord. The optic nerve showed extensive demyelination accompanied by axon depletion. The spinal cord lesions were found in C8 to L2 level (contiguous 15 segments), especially Th5 to Th11 level. The thoracic spinal cord showed extensive remyelination spreading from the entry zone of peripheral nerves to the central portion. Regenerative myelin showed immunopositivity for Schwann/2E, a marker of Schwann cells and myelin of the peripheral nervous system. Expressions of glial fibrillary acidic protein and aquaporin 4 (AQP4) were weakened in the area of Schwann cell remyelination, suggesting that the essential pathogenesis of this case was disturbance of astrocytes. Inhibition of gliosis probably led to cystic cavities, and destruction of basal lamina may have permitted Schwann cells of peripheral nerves to enter the spinal cord and proliferate within empty spaces. Compared with the optic tract and the spinal cord lesions, a large part of the brain plaques was vague and inactive. We pathologically diagnosed this case as NMO for optic neuritis, myelitis, a contiguous spinal cord lesion and loss or decrease of AQP4 expression. 相似文献