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41.
Toshiko Sawaguchi Patricia Franco Hazim Kadhim Jose Groswasser Martine Sottiaux Hiroshi Nishida Andre Kahn 《Pathophysiology》2004,10(3-4):223-228
Background: The Ki-67 antigen appears in all human proliferating cells during late G1, S, M and G2 phases of the cell cycle, but is consistently absent in the Go phase (noncycling) cells. The correlation between Ki-67 in the brainstem and sleep apnea in victims of the sudden infant death syndrome (SIDS) was investigated to elucidate cell kinetics in the brainstem of this condition, which is still the main cause of postneonatal infant death. Materials and methods: Twenty-six cases of SIDS occurred among 38 infants dying under 6 months of age in a cohort of 27,000 infants studied prospectively to characterize their sleep–wake behavior. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and duration of sleep apnea were analyzed. At autopsy, brainstem material was collected and immunohistochemistry for Ki-67 was carried out. The density of Ki-67-positive neurons was measured semiquantitatively. Correlation analyses were carried out between the density of Ki-67-positive neurons and the data on sleep apnea. Results: Except in two cases in SIDS victims and in one control, the detection of Ki-67 was negative. No correlation analysis between the Ki-67 and of sleep apnea was found. Conclusions: There were no abnormal cell kinetics detected by the demonstration of Ki-67 antigen in the brainstems of SIDS victims. 相似文献
42.
Active matrix metalloproteinases in the tear fluid of individuals with vernal keratoconjunctivitis 总被引:3,自引:0,他引:3
Kumagai N Yamamoto K Fukuda K Nakamura Y Fujitsu Y Nuno Y Nishida T 《The Journal of allergy and clinical immunology》2002,110(3):489-491
Corneal epithelial lesions distinguish vernal keratoconjunctivitis (VKC) from other ocular allergic diseases. Such lesions result from degradation of the corneal epithelial basement membrane, which comprises mostly type IV collagen and laminin. Matrix metalloproteinase 2 (MMP-2) and MMP-9 catalyze the degradation of these 2 extracellular matrix proteins. The possible role of MMP-2 and MMP-9 in the pathogenesis of corneal lesions associated with VKC was investigated by assaying tear fluid for the presence of these enzymes. Tear fluid was collected from 6 eyes of 6 patients with active VKC, 14 eyes of 14 patients with active allergic conjunctivitis, and 6 eyes of 6 nonallergic healthy volunteers. Gelatin zymography revealed that the tear fluid of healthy volunteers contained inactive proforms of both MMP-2 and MMP-9 but not the active forms of these enzymes. Active forms of MMP-2 or MMP-9 were detected in a minority of patients with allergic conjunctivitis. However, with the exception of one individual for whom active MMP-9 was not detected, tear fluid from all patients with VKC contained both proforms and active forms of MMP-2 and MMP-9. These results implicate MMP-2 and MMP-9 in the pathogenesis of corneal epithelial disorders associated with VKC. 相似文献
43.
Induction of Mucosal B-Cell Memory by Intranasal Immunization of Mice with Respiratory Syncytial Virus 总被引:1,自引:0,他引:1 下载免费PDF全文
Janine Valosky Haruka Hishiki Theoklis E. Zaoutis Susan E. Coffin 《Clinical and Vaccine Immunology : CVI》2005,12(1):171-179
The capacity of live or inactivated respiratory syncytial virus (RSV) to induce B-cell memory in respiratory-associated lymphoid tissues of mice was examined. Eight weeks after primary inoculation with either live or inactivated RSV, adult BALB/c mice were challenged with 4 × 105 PFU of RSV. Protection from viral shedding and mucosal production of RSV-specific antibodies were examined at various time points after challenge. We found that primary immunization with live, but not inactivated, RSV induced complete and durable protection upon challenge within the upper and lower respiratory tract. Also, primary immunization with live, but not inactivated, RSV enhanced the production of mucosal RSV-specific immunoglobulin A (IgA) upon challenge. Secondary mucosal IgA responses were characterized by (i) the early production of mucosal IgA by B cells that reside in organized nasal-associated lymphoid tissues, cervical lymph nodes, and bronchial lymph nodes, and (ii) the subsequent production of RSV-specific IgA by mucosal effector tissues, such as the tracheal lamina propria and lung. These findings suggest that primary infection of mice with live RSV might induce mucosal IgA-committed memory B cells. A greater understanding of the characteristics of RSA-specific mucosal memory B cells may facilitate the development of an RSV vaccine. 相似文献
44.
This study was performed to investigate the mechanism involved in a decrease in the serum glucose of golden hamsters infected with plerocercoids of Spirometra erinacei. The concentration of glucagon, the activity of glucose-6-phosphatase in the liver, and the in vivo incorporation of 2-deoxyd-[1,2-3H]glucose into various organs increased in plerocercoid-infected hamsters compared with controls. Furthermore, the serum from the plerocercoid-infected hamsters enhanced the in vitro incorporation of [U-14C]glucose into adipose tissues, compared with control serum. The serum levels of immunoreactive insulin and somatomedin associated with nonsuppressible insulin-like activity in experimental animals, however, were not significantly different from those in controls. Therefore, we conclude that the decrease in serum glucose associated with plerocercoid infection is not the result of a decrease in gluconeogenesis, but the result of an increased utilization of glucose in the peripheral tissues. 相似文献
45.
Yoshimitsu Fukushima Keiko Wakui Toshiro Nishida Yasuo Ueoka 《American journal of medical genetics. Part A》1991,40(4):485-487
We report on a boy with the blepharophimosis sequence and de novo, apparently balanced reciprocal translocation between 3q23 and 4p15.2 [46, XY,t(3;4)(q23;p15.2)de novo]. Possible assignment of this autosomal dominant disorder is discussed. A 3q23 band is a more preferable gene locus of the blepharophi mosis sequence, based on the comparison of clinical manifestations between 4p- and 3q-syndromes. 相似文献
46.
Kai K Nasu K Nakamura S Fukuda J Nishida M Miyakawa I 《Molecular human reproduction》2002,8(2):176-180
Human endometrial stromal cells (ESC) can produce a variety of chemokines, especially after inflammatory stimulation. Interferon-gamma-inducible protein-10 (IP-10) is a potent chemoattractant for lymphocytes, and belongs to the family of non-ELR CXC chemokines. The expression of IP-10 in ESC after stimulation with interferon-gamma (IFN-gamma), interleukin-1 beta (IL-1 beta), tumour necrosis factor-alpha (TNF-alpha), or lipopolysaccharide (LPS) was evaluated using an enzyme-linked immunosorbent assay and Northern blot analysis. A small amount of IP-10 protein was detected in the culture media of unstimulated ESC. The expression of IP-10 mRNA was detected in ESC. IFN-gamma, IL-1 beta, TNF-alpha and LPS significantly stimulated the expression of IP-10 mRNA and protein in ESC. These results suggest that the production of IP-10 by ESC is regulated by inflammatory mediators. The modulation of IP-10 concentrations in the local environment may contribute to the normal and pathological processes of human reproduction by regulating leukocyte trafficking in the endometrium. 相似文献
47.
48.
Histopathological characterization of aortic intimal sarcoma with multiple tumor emboli 总被引:2,自引:0,他引:2
Nishida N Yutani C Ishibashi-Ueda H Tsukamoto Y Ikeda Y Nakamura Y 《Pathology international》2000,50(11):923-927
A case of aortic intimal sarcoma with multiple tumor emboli and distal metastasis is reported. All metastasis (adrenal, spleen) were via the arteries. This case also had independent lung cancer. Macroscopically, the aortic tumor did not form a bulged mass, but had linear ulceration with abundant mural thrombi. Poorly cohesive large atypical cells were seen in the intima of the abdominal aorta without invasion into the media. Tumor cells were disseminated into the mural thrombi on the aorta and embolized its branches. In the metastatic tumor or tumor emboli of the distal artery, there were not only large atypical cells, but also the foci of spindle-shaped cells or epithelioid differentiation. Tumor cells in the aorta were immunohistochemically positive for only vimentin. Muscle-specific actin was positive focally for spindle-shaped cells of tumor emboli and metastatic tumors. Furthermore, cytokeratin-positive cells were scatteredly seen. All tumor cells were negative for factor VIII and did not have a histologic or phenotypic analogy with lung cancer. The primary intimal sarcoma in the present case was of undifferentiated non-endothelial intimal stromal cell origin, and may have had multipotential for differentiation. Investigation of the metastatic site was useful for recognizing the features of this tumor. 相似文献
49.
50.
Nishida S Sasaki Y Murakami I Watanabe T Tootell RB 《Journal of neurophysiology》2003,90(5):3242-3254
Psychophysical findings have revealed a functional segregation of processing for 1st-order motion (movement of luminance modulation) and 2nd-order motion (e.g., movement of contrast modulation). However neural correlates of this psychophysical distinction remain controversial. To test for a corresponding anatomical segregation, we conducted a new functional magnetic resonance imaging (fMRI) study to localize direction-selective cortical mechanisms for 1st- and 2nd-order motion stimuli, by measuring direction-contingent response changes induced by motion adaptation, with deliberate control of attention. The 2nd-order motion stimulus generated direction-selective adaptation in a wide range of visual cortical areas, including areas V1, V2, V3, VP, V3A, V4v, and MT+. Moreover, the pattern of activity was similar to that obtained with 1st-order motion stimuli. Contrary to expectations from psychophysics, these results suggest that in the human visual cortex, the direction of 2nd-order motion is represented as early as V1. In addition, we found no obvious anatomical segregation in the neural substrates for 1st- and 2nd-order motion processing that can be resolved using standard fMRI. 相似文献