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101.
102.
Serum lipid, lipoprotein, apolipoprotein, and sterol profiles were studied in 22 patients with senile dementia of the Alzheimer type (SDAT) and 29 patients with vascular dementia (VD). Levels of high density lipoprotein-cholesterol (HDL-C) were lower in both patients groups of SDAT and VD than in control group. Apolipoprotein AI and AII are two major proteins in HDL. In this study, apolipoprotein AI levels were normal, but apolipoprotein AII levels were lower in the patient groups, especially in the VD group, than in the control group. Lipoprotein(a) levels were higher in both patient groups, especially in the VD group. There were no differences of cholesterol, cholesterol precursors (desmosterol and lathosterol), and plant sterols (campesterol and beta-sitosterol) among the three groups. Murine apolipoprotein AII is a serum precursor of murine senile amyloid protein, and the apolipoprotein AII variant with proline-->glutamine substitution at position 5 in the serum of accelerated senescence-prone mice is identical to the murine senile amyloid fibril protein from amyloid-deposited tissues of these mice. In human SDAT and VD, the reason for the low level of apolipoprotein AII remains unclear.  相似文献   
103.
N Uemura  K Ozawa  A Tojo  K Takahashi  A Okano  H Karasuyama  K Tani  S Asano 《Blood》1992,80(12):3198-3204
Since the ras family of proto-oncogenes is supposed to be involved in leukemogenesis by point-mutational activation, we studied the effect of the activated ras gene on the growth of a murine interleukin-3 (IL-3)-dependent cell line, FDC-P2. The human activated c-H-ras gene was transfected into FDC-P2 cells by electroporation using a high-level expression vector, BMGhph, which contains a partial DNA sequence from bovine papillomavirus (BPV) and a hygromycin B (hmB)-resistant gene as a selectable marker. The transformed FDC-P2 cells showed a high incidence of IL-3-independent growth and tumorigenicity in nude mice. These clones did not express or secrete IL-3, suggesting the acquisition of IL-3 independence by a nonautocrine mechanism. The high incidence of autonomous growth may be due to the use of the BMG vector, because (1) the activated ras gene in pBR322 vector (pHs-49) was not so efficient in the induction of IL-3 independence, (2) the c-H-ras genome copies per cell increased in number up to about 50 copies by using the BMG vector, and (3) cotransfection with the activated ras gene and the BPV gene in separate plasmids partly enhanced the incidence of autonomous growth without increasing the copy number of the ras gene compared with transfection with the activated ras gene alone. The present study supports the idea that the activation of ras gene is an important step in malignant transformation of hematopoietic cells and suggests that the BPV gene products may cooperate with ras gene activation probably by affecting the cellular genes that may be involved in multistep leukemogenesis. The BMG vector may be useful to test the transforming ability of oncogenes whose oncogenic potential is relatively low.  相似文献   
104.
105.
We have reported that the differentiation-inducing factor (DIF) is present in conditioned medium of mouse osteoblast-like cell (MC3T3-E1) cultures. In the present study, the DIF from conditioned medium of MC3T3-E1 cells was partially purified and its biologic activity was examined. The DIF was purified by monitoring the induction of phagocytic activity of mouse myeloblastic leukemia cells (M1). The DIF induced differentiation of not only M1 cells but also mouse myelomonocytic cells (WEHI-3). Furthermore, the DIF increased the in vitro bone-resorbing activity and the osteoclast number in mouse calvaria. The increases were inhibited by the addition of either salmon calcitonin or indomethacin. When mouse bone marrow cells were cultured with the DIF for 8 days, formation of osteoclast-like multinucleated cells was stimulated dose dependently. The DIF from MC3T3-E1 cells appeared to be different from interleukin-1 (IL-1), tumor necrosis factor (TNF), and transforming growth factor beta (TGF-beta). These results suggest that the DIF partially purified from osteoblast-like cell cultures stimulates osteoclastic bone resorption by promoting differentiation and fusion of osteoclast progenitors to form multinucleated osteoclasts.  相似文献   
106.
The changes of cellular protein spots in human stomach carcinomas (Exp 4, H-111) and colon carcinomas (SW403, SW480) implanted into nude mice were examined after administration of MMC. The results were as follows. 1) Exp4 histologically showed pleomorphism after treatment by MMC. In other tumors no changes in histological features were shown. 2) The most remarkable decreases of p protein spots in Exp4, and moderate decreases of protein spots in SW403 and SW480 were admitted, contrasting to no changes in the pattern of protein spots in H-111. 3) The decreases of protein spots in the tumors were related to the sensitivities to MMC. 4) Regrowth tumors in Exp4 which were survived after administration of MMC revealed similar protein spots patterns and histological features to those in control tumors. 5) The changes in protein spots in the liver and kidney derived from normal mice were also examined. In these, protein spots patterns showed no changes after administration of MMC. These results suggest that the cellular protein sports were decreased in accordance with effect of MMC in the tumors.  相似文献   
107.
Summary An esthesioneuroblastoma in a 16-year-old male was studied ultrastructurally and immunohistochemically, using antiserum against tyrosine hydroxylase (TH), a rate-limiting enzyme in the catecholamine-synthesizing pathway. Tumor cells were fairly uniform in appearance, showing scantly cosinophilic cytoplasm and round to oval hyperchromatic nuclei, and were arranged in nests and cords of various sizes. Ultrastructurally, individual tumor cells had well-developed cell organelles including polyribosomes, microtubules, intermediate filaments, centrioles, Golgi apparatus and mitochondria. Secretory-like granules were occasionally found, predominantly in the cell processes. Immunohistochemically, many tumor cells were shown to be immunoreactive for TH. This finding strongly suggested that the present tumor was capable of producing catecholamines and that it might be derived from certain sympathetic neuronal cell nests in the superior nasal cavity.  相似文献   
108.
The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI.  相似文献   
109.
Prosthetic valve endocarditis (PVE) caused by Candida species is associated with high morbidity and mortality. A combination of surgical resection and antifungal drug therapy is the golden standard for treatment, yet surgical intervention is not possible in all cases of Candida PVE. We report a case of PVE due to Candida albicans cured by medical treatment alone. This case suggests that, in some instances, Candida PVE can be managed medically with antifungal therapy. Such a conservative approach should be applied with caution and necessitates very close follow-up on a long-term basis.  相似文献   
110.
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.  相似文献   
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