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Limited diversity of the protein D gene (hpd) among encapsulated and nonencapsulated Haemophilus influenzae strains. 下载免费PDF全文
Protein D is a surface-exposed lipoprotein of the gram-negative bacterium Haemophilus influenzae with affinity for human immunoglobulin D myeloma protein. The gene encoding protein D (hpd) in a serotype b strain of H. influenzae was cloned. Escherichia coli carrying the hpd gene bound human myeloma immunoglobulin D. Nucleotide sequence analysis identified an 1,092-bp open reading frame that was more than 99% identical to the hpd gene from a nontypeable H. influenzae strain. In the deduced amino acid sequences for protein D, only 2 of 364 amino acid residues differed. The restriction fragment length polymorphism of the hpd region in different strains was analyzed by Southern blot analyses of PstI- or EcoRI-digested genomic DNA from 100 H. influenzae strains. The analysis was performed by using isolated fragments of the cloned hpd gene, originating from the nontypeable H. influenzae 772, as probes. All strains tested had DNA sequences with a high degree of homology to the hpd probes. The analysis also showed that restriction endonuclease sites within the gene were more conserved than sites adjacent to the hpd gene. An interesting difference between type b strains and unencapsulated strains was observed. The majority of type b strains seem to have a 1.4-kbp DNA fragment upstream of the hpd gene that is absent in nontypeable strains. On the basis of the high degree of conservation of the hpd gene among H. influenzae strains, we conclude that protein D is a possible vaccine candidate. 相似文献
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Qunn L Takemura T Ikushima S Ando T Yanagawa T Akiyama O Oritsu M Tanaka N Kuroki T 《Virchows Archiv : an international journal of pathology》2002,441(3):271-278
Seventy-two cases of idiopathic pulmonary fibrosis (IPF) were examined from 2856 consecutive autopsy cases at the Japanese Red Cross Medical Center in Tokyo from 1973-1996. Primary lung cancer had arisen in 31 of 72 cases of IPF (43%), significantly higher than the incidence in cases without IPF (8.1%) and in the cases with non-IPF chronic lung diseases (11.9%). Hyperplastic epithelial foci in the honeycomb lesions of IPF cases were significantly more prominent in the lower than in the upper lobe, in cases with or without lung cancer, and they were more prominent in the lower lobe of IPF with than in those without cancer. The length of hyperplastic epithelial foci in the lower lobe of IPF cases was longer than that in interstitial pneumonia-associated with collagen vascular diseases. There was a higher PCNA labeling index of hyperplastic epithelial foci in IPF cases than in cases of interstitial pneumonia-associated with collagen vascular diseases. The PCNA labeling index was almost the same between smokers and nonsmokers with IPF. Overexpression of p53 was observed in hyperplastic epithelial foci in honeycomb lesion of IPF. DNA ploidy analysis of hyperplastic epithelial foci in the paraffin sections of 12 IPF cases revealed aneuploidy patterns in eight cases. These results strongly suggest that accelerated cell proliferation occurs in the honeycomb lesion of IPF, and that regenerative epithelia becomes susceptible to carcinogenic agents in addition to the smoking effect. 相似文献
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Yasuyuki Sumikawa Yuriko Ueki Akira Miyoshi Lei Cheng Min Yin Hai-Bo Shi Masuko Daitoku Sumikawa Takeshi Kono Toshiyuki Aoki Ichiro Katayama 《Arerugī》2007,56(10):1270-1275
BACKGROUND: The comparative studies of the prevalence of atopic dermatitis and skin barrier functions in Japanese and Chinese were performed. METHODS: Clinical investigations were performed in 68 elementary school students in Lhasa, Tibet Autonomous Region and 67 students in Yixing, Jiangsu Province in China, and 99 students in Nishinomiya, Hyogo in Japan. Transepidermal water loss (TEWL) and capacitance were measured. Questionary survey about bathing frequency was also performed for students in Lhasa, Yixing and Osaka. RESULT: The prevalence rate of atopic dermatitis was 0% in Lhasa, 2.63% in Yixing, 4.26% in Nishinomiya. TEWL of students in Nishinomiya was higher than that in Yixing and Lhasa. Capacitance of students in Lhasa was lower than that in Nishinomiya and Yixing. The frequency of taking a bath in Lhasa was about 2.2 times per month and fewer than that in Nishinomiya and Yixing. CONCLUSION: There was tendency that the prevalence of atopic dermatitis increased according to increase of TEWL. It was thought that more investigations are necessary whether the development of habitat and environment influence the prevalence of atopic dermatitis and skin barrier function. 相似文献
36.
硅凝胶人工晶体的生物相容性 总被引:3,自引:0,他引:3
本文参照国内外有关医用高分子材料的生物学评价试验方法,对国产医用级硅凝胶人工晶体作了系统的生物学评价。结果表明:硅凝胶人工晶体对眼及皮肤无刺激作用、无热原、无毒性、体外溶血率小于5%,对细胞生长有促进作用,长期植入皮下时,随植入时间延长,囊壁厚度逐渐变薄,炎性细胞反应30天基本消失。染色体及骨髓多染红细胞未受影响。因此,可以认为硅凝胶人工晶体有良好的生物相容性。 相似文献
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Bluestone AY Stewart M Lei B Kass IS Lasker J Abdoulaev GS Hielscher AH 《Journal of biomedical optics》2004,9(5):1063-1073
This is the second part of a two-part study that explores the feasibility of 3-D, volumetric brain imaging in small animals by optical tomographic techniques. In part 1, we demonstrated the ability to visualize global hemodynamic changes in the rat head in response to elevated levels of CO(2) using a continuous-wave instrument and model-based iterative image reconstruction (MOBIIR) algorithm. Now we focus on lateralized, monohemispherically localized hemodynamic effects generated by unilateral common carotid artery (CCA) occlusion. This illustrates the capability of our optical tomographic system to localize and distinguish hemodynamic responses in different parts of the brain. Unilateral carotid occlusions are performed in ten rodents under two experimental conditions. In the first set of experiments the normal systemic blood pressure is lowered to 50 mmHg, and on unilateral carotid occlusion, we observe an ipsilateral monohemispheric global decrease in blood volume and oxygenation. This finding is consistent with the known physiologic response to cerebral ischemia. In a second set of experiments designed to observe the spatial-temporal dynamics of CCA occlusion at normotensive blood pressure, more complex phenomena are observed. We find three different types of responses, which can be categorized as compensation, overcompensation, and noncompensation. 相似文献
39.
目的探讨高压氧对脑缺血再灌流脑皮层一氧化氮(NO)生成的影响及其对脑细胞的保护作用。方法采用沙土鼠双侧颈总动脉夹闭30min再灌流模型。用电化学及免疫细胞化学方法检测脑皮层一氧化氮生成、一氧化氮合酶(NOS)表达及神经细胞凋亡。结果缺血再灌流期沙土鼠脑皮层中NO的含量显著增加,3型NOS均有表达,缺血再灌流第2d,iNOS的表达最为明显,同时NO的生成达到高峰。缺血再灌流第1、2、3d,沙土鼠脑皮层均可见凋亡细胞,以第2、3d更为明显。高压氧暴露能明显抑制iNOS表达,减少NO生成,减轻神经细胞凋亡。结论高压氧能抑制沙土鼠脑缺血再灌流期脑皮层NO生成,减轻神经细胞凋亡,从而起到脑保护作用。 相似文献
40.