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71.
Yasunari Nakamoto Shuichi Kaneko Masao Honda Masashi Unoura Jaehun Cheong Akihisa Harada Kouji Matsushima Kenichi Kobayashi Seishi Murakami 《Journal of medical virology》1994,42(4):374-379
The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc. 相似文献
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Toshio Morohoshi Tetsuya Hamamoto Toshiaki Kunimura Etsuko Yoshida Mikio Kanda Kenichi Funo Takehisa Nagayama Masayuki Maeda Shunji Araki 《Pathology international》1991,41(12):916-921
A rare case of splenic epidermoid cyst (SEC) of the pancreas discovered in a 32-year-old Japanese female is reported. The lesion, 5x6cm in size including caseous material and serous fluid in the lumen, was discovered by ultrasonography and computed tomography at the tail of the pancreas and was easily removed. Histopathologically, the cystic wall consisted of three components: the inside was lined by mature squamous epithelium with keratinization, the middle layer consisted of splenic pulp with a sinus structure, and the peripheral layer was dense fibrous connective tissue in which some involutional pancreatic ducts and islets were recognized. The literature about SEC of the pancreas is discussed in comparison with other types of epidermoid cyst including lymphoepithelial cyst and dermoid cyst in the pancreas. Acta Pathol Jpn 41: 916 921, 1991. 相似文献
75.
Sato Y Harada K Sudo Y Watanabe K Nakahama T Morimoto H Nakanuma Y 《Pathology international》2002,52(7):478-482
Autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) are representative autoimmune liver diseases in which hepatocytes and intrahepatic bile ducts, respectively, are selectively damaged by autoimmune mechanisms. Bile duct injury and loss is characteristic of PBC and chronic non-suppurative destructive cholangitis (CNSDC), in particular, is a histological hallmark of PBC. In this report, we present an unusual case of AIH accompanied by CNSDC-like bile duct injury in a 46-year-old woman. The patient's serum aminotransferase level was abnormally high. The serum levels of alkaline phosphatase, gamma-GTP and IgG were also elevated, but the IgM level was within normal limits. The titer of antismooth muscle antibody (SMA) was 1:80, while antinuclear autoantibody (ANA) and the M2 fraction of antimitochondrial antibody (AMA) were both negative. Liver biopsy disclosed CNSDC-like bile duct injuries and severe interface hepatitis and lobular hepatitis with perivenular zonal necrosis were observed. The aggregate score of the International Autoimmune Hepatitis Group corresponded to the category of probable AIH. Immunohistochemically, histocompatibility leukocyte antigen-DR, which is aberrantly expressed in the damaged bile ducts of PBC, was not found in the injured bile ducts of this case. Laboratory data were much improved by treatment with prednisone, but ursodeoxycholic acid was not effective. Although the possibility of an overlapping syndrome of AIH- and AMA-negative PBC could not be excluded, this case was diagnosed as AIH with CNSDC-like bile duct lesions. 相似文献
76.
Difference in antibody reactivity between complement fixation and immune adherence hemagglutination tests with virus antigens. 下载免费PDF全文
Complement-fixing (CF) immunoglobulin M antibody to infantile gastroenteritis virus (a rotavirus) did not show the reactivity of immune adherence hemagglutination (IAHA). Early immunoglobulin G CF antibody produced both in patients and in guinea pigs experimentally infected with Japanese encephalitis virus (a flavivirus) had weak reactivity in IAHA test. However, late antibody showed higher titers by IAHA than by CF. These results suggested that early antibodies with lower affinity are inefficient in the IAHA reaction. The implications of this study are: (i) a low ratio of IAHA/CF antibody titers in a serum suggests a recent rotavirus infection; (ii) the IAHA reaction is more type specific than the CF reaction for identifying the serotype of antigenically cross-reacting viruses with hyperimmune sera. 相似文献
77.
Honda T Ota H Arai K Hayama M Fujimoto K Yamazaki Y Haniuda M 《Virchows Archiv : an international journal of pathology》2002,441(1):47-52
The etiology of usual interstitial pneumonia (UIP), a progressive lung disease, remains unclear. We examined alveolar structure in UIP three-dimensionally. Lung biopsy specimens from five patients with idiopathic pulmonary fibrosis were used. Sections 150-microm thick were stained with elastica solution for elastic fibers, with alpha-smooth muscle actin antibody for myofibroblasts, with anti-Thomsen-Friedenreich antibody for type-II pneumocytes and with anti-CD34 antibody for blood vessels. We examined them three-dimensionally using a laser confocal microscope or light microscope. In the fibrotic lesions, the thick elastic fibers forming the alveolar framework were not particularly dense considering the reduction in alveolar volume. Near the fibrotic lesions, some of the thin elastic fibers in the alveolar wall were slightly sinuous and ended with rounded tips. Type-II pneumocytes had proliferated and were distributed uniformly over the alveolar surface. Smooth muscle actin filaments were detected only around the alveolar orifice. These findings show that in UIP destruction of the elastic fiber framework of the alveoli may lead to irreversible focal alveolar collapse after damage to the alveolar epithelial cells, and proliferation of type-II pneumocytes may be involved with this elastolysis. 相似文献
78.
Suzuki H Uchiyama M Tagaya H Ozaki A Kuriyama K Aritake S Shibui K Tan X Kamei Y Kuga R 《Sleep》2004,27(8):1486-1490
STUDY OBJECTIVES: There is a long-standing controversy surrounding the existence of dream experiences during non-rapid eye movement (NREM) sleep. Previous studies have not answered the question whether this "NREM dream" originates from the NREM sleep mechanism because the subject might simply be recalling experiences from the preceding rapid eye movement (REM) sleep. METHODS: We scheduled 11 healthy men to repeat 20-minute nap trials separated by 40-minute periods of enforced wakefulness across a period of 3 days. At the end of the nap trial, each participant answered questions regarding the formal aspects of his dream experiences during the nap trial, using the structured interviews. RESULTS: We obtained a total of 172 dream reports after naps containing REM sleep (REM naps) and 563 after naps consisting of only NREM sleep (NREM naps). Dream reports from NREM naps were less remarkable in quantity, vividness, and emotion than those from REM naps and were obtained more frequently during the morning hours when the occurrences of REM sleep were highest. CONCLUSIONS: These results suggest that the polysomnographic manifestations of REM sleep are not required for dream experiences but that the mechanisms driving REM sleep alter experiences during NREM sleep in the morning. A subcortical activation similar to REM sleep may occur in human NREM sleep during the morning when REM sleep is most likely to occur, resulting in dream experiences during NREM sleep. 相似文献
79.
Implantation study of a novel hydroxyapatite/collagen (HAp/col) composite into weight-bearing sites of dogs 总被引:2,自引:0,他引:2
Itoh S Kikuchi M Takakuda K Nagaoka K Koyama Y Tanaka J Shinomiya K 《Journal of biomedical materials research》2002,63(5):507-515
A hydroxyapatite/type I collagen (HAp/Col) composite, aligning hydroxyapatite nanocrystals along collagen molecules, has been prepared. The biocompatibility, osteoconductive activity, and efficacy as a carrier of rhBMP-2 of this novel biomaterial implanted in the weight-bearing site have been examined. The HAp/Col implants (15 mm in diameter and 20 mm in length) with a surface cross-linked layer containing rhBMP-2 (0 or 400 microg/ml) were implanted into bone defects of tibiae in three beagle dogs and fixed according to the Ilizarov method. As a control, bone defects of 20 mm in two beagle dogs did not receive implants, and the dogs were allowed to walk using an Ilizarov extraskeletal fixator. The specimens were removed from one dog in each group after 12 weeks. Also, the Ilizarov fixators in the rhBMP-treated dogs were removed after 12 weeks, after which full weight bearing started. The specimens were further taken out after 18 and 24 weeks in the rhBMP-treated and non-rhBMP-treated dogs, and after 24 weeks in the control group. The change of bone mineral density, as well as radiological and histological findings, suggest that the implants are able to induce bone remodeling units and are a superior carrier of rhBMP-2 due to the stimulation of early callus and new bone formation. 相似文献
80.
BDNF increases release probability and the size of a rapidly recycling vesicle pool within rat hippocampal excitatory synapses 总被引:2,自引:1,他引:2
William J. Tyler Xiao-lei Zhang Kenichi Hartman Jochen Winterer Wolfgang Muller Patric K. Stanton Lucas Pozzo-Miller 《The Journal of physiology》2006,574(3):787-803
Exerting its actions pre-, post- and peri-synaptically, brain-derived neurotrophic factor (BDNF) is one of the most potent modulators of hippocampal synaptic function. Here, we examined the effects of BDNF on a rapidly recycling pool (RRP) of vesicles within excitatory synapses. First, we estimated vesicular release in hippocampal cultures by performing FM4-64 imaging in terminals impinging on enhanced green fluorescent protein (eGFP)-labelled dendritic spines – a hallmark of excitatory synapses. Consistent with a modulation of the RRP, BDNF increased the evoked destaining rate of FM4-64 only during the initial phase of field stimulation. Multiphoton microscopy in acute hippocampal slices confirmed these observations by selectively imaging the RRP, which was loaded with FM1-43 by hyperosmotic shock. Slices exposed to BDNF showed an increase in the evoked and spontaneous rates of FM1-43 destaining from terminals in CA1 stratum radiatum, mostly representing excitatory terminals of Schaffer collaterals. Variance-mean analysis of evoked EPSCs in CA1 pyramidal neurons further confirmed that release probability is increased in BDNF-treated slices, without changes in the number of independent release sites or average postsynaptic quantal amplitude. Because BDNF was absent during dye loading, imaging, destaining and whole-cell recordings, these results demonstrate that BDNF induces a long-lasting enhancement in the probability of transmitter release at hippocampal excitatory synapses by modulating the RRP. Since the endogenous BDNF scavenger TrkB-IgG prevented the enhancement of FM1-43 destaining rate caused by induction of long-term potentiation in acute hippocampal slices, the modulation of a rapidly recycling vesicle pool may underlie the role of BDNF in hippocampal long-term synaptic plasticity. 相似文献