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1.
Widespread occurrence of AP in amyloidotic tissues. An immunohistochemical observation 总被引:1,自引:0,他引:1
T Shirahama M Skinner J D Sipe A S Cohen 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,48(3):197-206
Plasma (P)-component of amyloid (AP or SAP), while not an integral part of the amyloid fibril, has been considered to be intimately associated with virtually every different type of amyloid. In the present study, we evaluated the distribution of AP in the organs frequently involved in two forms of human systemic amyloidosis (AA and AF) and in mouse AA amyloidosis, by use of immunohistochemistry with anti-AP. Although the amyloid deposits generally showed moderate reactions with anti-AP, they were not always clearly distinguished from the surrounding non-amyloid tissue elements which often stained as well. The basement membrane often showed even stronger reaction to anti-AP than the adjacent amyloid deposits, and liver sections demonstrated such a high overall reaction to anti-AP that the anti-AP reaction on the amyloid deposits was often obscurred. The present results suggest that the binding between AP and the amyloid fibril may not be monospecific, that AP by this technique occurs rather widely throughout the body, and therefore that anti-AP may not be considered as specific a marker for amyloid deposits in immunohistochemical and perhaps other studies as well. 相似文献
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3.
Differential expression of the amyloid SAA 3 gene in liver and peritoneal macrophages of mice undergoing dissimilar inflammatory episodes 总被引:3,自引:0,他引:3
H Rokita T Shirahama A S Cohen R L Meek E P Benditt J D Sipe 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(11):3849-3853
The three active serum amyloid A (SAA) genes of mice, SAA 1, SAA 2, and SAA 3, are coordinately expressed in liver during acute and chronic inflammatory stimulation and experimental amyloidosis. The genes, primarily SAA 3, are also expressed extrahepatically. The apoprotein SAA 2 is the precursor of the amyloid A (AA) fibril protein that is deposited as insoluble fibrils extracellularly in spleen and other organs when amyloidosis occurs secondarily to inflammation. The exact cause of AA fibril formation is unknown. Amyloid enhancing factor is a high m.w. glycoprotein extracted from amyloidotic organs. Administration of amyloid enhancing factor alters experimental inflammation to bring about accelerated deposition of amyloid A fibrils first in spleen and later in other organs. In this study, hepatic and extrahepatic expression of the SAA genes were compared during accelerated amyloidosis relative to inflammation uncomplicated by amyloidosis. Differences in kinetics and pattern of SAA gene expression by resident peritoneal macrophages and liver were detected during four dissimilar inflammatory episodes. Macrophages expressed the SAA 3 gene solely, and to a greater extent in chronic than in acute inflammation. In accelerated amyloid induction, macrophage SAA 3 expression increased as SAA 1 and SAA 2 expression in liver decreased. However, alpha-1-acid glycoprotein expression remained elevated throughout the course of amyloid induction. The greatly increased expression of the SAA 3 gene by macrophages and decreased expression of the SAA 1 and SAA 2 genes in liver during amyloidosis, suggests that altered SAA gene expression may play a pathogenetic role in experimental amyloid deposition. 相似文献
4.
Masanori Kasahara Toshinao Takenouchi Kazumasa Ogasawara Hitoshi Ikeda Tsuguyo Okuyama Naoshi Ishikawa Junko Moriuchi Akemi Wakisaka Yuko Kikuchi Miki Aizawa Takehisa Kaneko Noboru Kashiwagi Yasuharu Nishimura Takehiko Sasazuki 《Immunogenetics》1983,17(5):485-495
To study the gene products of the HLA complex, we produced two monoclonal antibodies, termed HU-18 and HU-23. They were active in complement-dependent cytotoxicity and detected B-cell alloantigens encoded by a locus (or loci) linked to HLA. When three types of HLA-DR4 homozygous B-cell lines with different HLA-D specificities were tested for reactivity with HU-18 and HU-23, they displayed distinct reaction patterns depending on the HLA-D specificities they possessed: EBV-Wa (HLA-DYT homozygous), negative for both HU-18 and HU-23; KT2 and KOB (HLA-DKT2 homozygous), positive only for HU-18; and ER (HLA-Dw4 homozygous), positive for both. These differential reaction patterns were further confirmed by testing against a panel of 17 HLA-DR4-positive peripheral blood lymphocytes with known HLA-D specificities. Thus, these monoclonal antibodies allow us to identify HLA-DYT, HLA-DKT2, and HLA-Dw4 solely by serologic methods. This is the first clearcut serologic identification of these three HLA-DR4-associated HLA-D specificities, which have been indistinguishable by conventional serology and identified only by cellular techniques. It is hoped that immunochemical investigations using HU-18 and HU-23 will advance our understanding of the HLA-D region on a molecular level. 相似文献
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Akira Nomura Yuko Yamazaki Takashi Tsuji Yukishige Kawasaki Shoji Tanaka 《Experimental cell research》1996,227(2):256
For all biological particles such as cells or cellular organelles, there are three-dimensional coordinates representing the centroid or center of gravity. These coordinates and other numerical parameters such as volume, fluorescence intensity, surface area, and shape are referred to in this paper as geometric properties, which may provide critical information for the clarification ofin situmechanisms of molecular and cellular functions in living organisms. We have established a method for the elucidation of these properties, designated the three-dimensional labeling program (3DLP). Algorithms of 3DLP are so simple that this method can be carried out through the use of software combinations in image analysis on a personal computer. To evaluate 3DLP, it was applied to a 32-cell-stage sea urchin embryo, double stained with FITC for cellular protein of blastomeres and propidium iodide for nuclear DNA. A stack of optical serial section images was obtained by confocal laser scanning microscopy. The method was found effective for determining geometric properties and should prove applicable to the study of many different kinds of biological particles in three-dimensional space. 相似文献
8.
Takeshi Minami Masayo Ichii Yoshiyuki Tohno Setsuko Tohno Masako Utsumi Masa-oki Yamada Yuko Okazaki 《Biological trace element research》1996,55(1-2):199-205
The purpose of this study was to determine the extent of aluminum (Al) accumulation in the human aorta and cerebral arteries.
The Al contents in the aortae and in the cerebral arteries from 23 human subjects was determined by inductively coupled plasma
atomic emission spectrophotometry (ICP-AES). The subjects' age range was 45–99-yr-old; 15 of the subjects were males and 8
were females. Al was detected in twelve aortae and in six cerebral arteries, when the entire specimen was analyzed. Two specimens
where Al was found in the cerebral arteries contained no Al in the aorta. No relationship to the subject's sex was found.
When related to age, two groups were established. Group L (45–75 yr old) and group H (>75 yr old), which exhibited aortal
Al concentrations of 33.3 and 72.7%, respectively. When the aortic wall was dissected into the tunica intima, media, and adventitia,
Al was found mainly in the tunica media. In the aorta, significant relationships were found between Al and phosphorus (P)
levels (r=0.801,p<0.01) and between Al and calcium (Ca) (r=0.661,p<0.05). We have concluded that Al accumulation is age-dependent and that it occurs both in the aorta and in the cerebral artery.
In the aorta, accumulation occurs mainly in the tunica media. Both P and Ca appear to enhance aortal Al accumulation. 相似文献
9.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba. 相似文献
10.
Stable isotopic structure of aquatic ecosystems 总被引:1,自引:0,他引:1
Isotopic, biogeochemical and ecological structure can provide a new dimension for understanding material flows, and the simultaneous
function and structure of an ecosystem. Distributions ofδ
13C andδ
15N for biogenic substances in the Nanakita river estuary involving Gamo lagoon in Japan were investigated to construct isotope
biogeochemical and ecological structure for assessing fate and transfer of organic matter, and food web structure. The isotopic
framework of the ecosystem was successfully described in aδ
15N–δ
13C map. In this estuary the variations of isotope ratios of biogenic substances were clearly explained by the mixing of land-derived
organic matter, and marine-derived organic matter.
A trophic-level effect of15N enrichment was clearly observed. Organisms were classified into three groups depending upon the contribution of land-derived
organic matter in a food chain. Almost all biota except mollusca in the lagoon depend on organic matter of marine origin.
The contributions of both land and marine organic matter were comparable for mollusca in the lagoon. 相似文献