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Protodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated. PD displayed strong growth inhibitory effect against HL-60 cells, but weak growth inhibitory effect on KATO III cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with PD, but not in KATO III cells treated with PD. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 75.2, 96.3, and 100% after a 3-day treatment with 2.5, 5, and 10 microM PD, respectively. The fragmentation by PD of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent in the HL-60 cells. These findings suggest that growth inhibition by PD of HL-60 cells results from the induction of apoptosis by this compound in HL-60 cells.  相似文献   
23.
To compare immunophenotypic and molecular features between Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) with c-myc rearrangements (c-mycR DLBCL), we analyzed 18 cases of B-cell non-Hodgkin's lymphoma with c-mycR that were confirmed by chromosomal and/or Southern blotting analyses. The cases were histologically classified into 10 BLs and five DLBCLs. The remaining three cases could not be classified because of suboptimal quality of the surgical materials. BLs were from five adults and five children, whereas all DLBCLs were from adults. BLs were positive for CD20 (10/10 cases examined), CD10 (9/10), Bcl-2 (1/9), and Bcl-6 (10/10), whereas they were negative for CD3 (0/10) and EBV (0/8), by Epstein-Barr virus (EBV) EBER-1 RNA in situ hybridization. c-MycR DLBCLs were positive for CD20 (5/5), CD10 (2/5), Bcl-2 (3/4), and Bcl-6 (4/4), whereas none of them were positive for CD3 and EBV. A mean of MIB-1 index (MIB-1+ cells/neoplastic cells, %) of BLs (98.1%) was higher than that of c-mycR DLBCLs (66.3%; P <.0001). Somatic mutation of immunoglobulin heavy-chain gene variable region (VH gene) in BLs (four cases) ranged from 0.7 to 4.9% with an average value of 2.3%, whereas those in DLBCLs (three cases) from 8.2 to 32.0% with an average value of 17.0%. It is, therefore, concluded that a growth fraction of nearly 100%, as well as a monotonous proliferation of medium-sized cells and c-myc(R), should be of value in the diagnosis of BL, which is probably different from c-myc(R) DLBCL. In addition, CD10+, Bcl-2-, and low frequency of mutation of the VH gene could be helpful for the histologic distinction of BL from (c-mycR) DLBCL.  相似文献   
24.
In order to clarify the histological and immunohistochemical characteristics of suppurative granuloma in abscess-forming granulomatous lymphadenitis (AGL), and the relation between AGL and cat scratch disease (CSD), 36 cases of AGL were studied. The combined results showed that there were two types of suppurative granulomas. The suppurative granulomas histologically revealed small lymphocytes of predominantly T cell phenotype distributed among the epithelioid histiocytes bordering central necrotic areas in the suppurative granulomas. These suppurative granulomas could be further subdivided into two groups, mainly those with and without the intermingling of large transformed cells of B-cell phenotypes: Type B granuloma with large transformed B cells and Type A without large transformed B cells. Both types of granulomas were observed in a varying degree in most cases. According to the predominant type of granulomas, 36 patients with AGL were further classified into two groups: Group I of Type A dominance and Group II of Type B dominance. Warthin-Starry (WS) silver stain positive bacteria, which are said to be a causative agent of CSD, were present in about 50% of both groups. No Brown-Hopps' Gram-positive bacteria, fungus, toxoplasma, Chlamydia or Bacillus Calmette-Guerin antigen were found in any case. Clinically, there was no significant difference between these two groups. On the other hand, the detection of WS-positive bacteria seemed to have some relationship with the duration of disease and the history of exposure to cats, and 70% of AGL cases occurred in autumn without a single concurrent epidemic.  相似文献   
25.
Balamuthia mandrillaris is a free-living ameba that causes granulomatous amebic encephalitis in both immunocompromised and immunocompetent individuals. Because of a lack of pathognomonic symptoms and the difficulty in recognizing amebas in biopsied tissues, most cases are not diagnosed or effectively treated, leading to a >95% mortality. We report here on five cases of balamuthiasis that were diagnosed by indirect immunofluorescence (IIF) staining of serum for anti-Balamuthia antibodies (titer > or = 1:128) and confirmed by IIF of unstained brain tissue sections and/or detection of amebas in hematoxylin-eosin-stained slides. Additionally, we have used the PCR for the detection of mitochondrial 16S rRNA gene DNA from the ameba in clinical specimens such as brain tissue and cerebrospinal fluid (CSF) from individuals with Balamuthia encephalitis. Balamuthia DNA was successfully detected by the PCR in clinical samples from all five individuals. It was detected in brain tissue from three cases, in CSF from three cases, and in one of two samples of lung tissue from two individuals, but not in two samples of kidney tissue tested. One sample of unfixed brain tissue was culture positive for Balamuthia. In order to test the sensitivity of the PCR for detection of Balamuthia DNA, CSF specimens from two individuals negative for amebic infection were spiked with Balamuthia amebas. We found that it was possible to detect Balamuthia DNA in the PCR mixtures containing mitochondrial DNA from 1 to as little as 0.2 ameba per reaction mixture. A single Balamuthia ameba contains multiple mitochondrial targets; thus, 0.2 ameba represents multiple targets for amplification and is not equivalent to 0.2 of an ameba as a target.  相似文献   
26.
A completely infarcted lymph node is an unusual event. However, lymph node infarction should alert the pathologist to the considerable likelihood of malignant lymphoma. We report two unusual cases of acute myeloid leukemia presenting with granulocytic sarcoma at disease onset with a lymph node lesion exhibiting extensive lymph node infarction. The infarcted tissue contained numerous eosinophilic cell ghosts. There were some islands of degenerated, pyknotic medium-sized nuclei resembling lymphoblasts present in the necrotic area. By immunohistochemistry, these medium sized cells were CD3-, CD20-, CD34+, CD43+, CD45RO-, CD68-, CD79a- and myeloperoxidase+ in both cases. Differentiation of granulocytic sarcoma from malignant lymphomas is important for adequate therapy. The present cases indicate that granulocytic sarcoma should be added to the list of differential diagnoses for lymph node infarction.  相似文献   
27.
There is disagreement among researchers concerning whether glutamatergic N-methyl-D-aspartate (NMDA) receptors play a role in constructing spatial representations. Therefore, the authors reexamined the effects of the NMDA antagonist on a spatial discrimination task using rats in a water pool. The authors confirmed that MK-801 impaired acquisition of the spatial discrimination task (Experiment 1). When rats were pretrained before drug treatment, MK-801 induced learning deficits in the novel environment but not in the familiar environment (Experiment 2). Moreover, in a familiar environment, MK-801 did not impair spatial learning, even when the task was completely novel for the rats (Experiment 3). These results suggest that NMDA receptors play an important role in the construction of spatial representations but not in the use of them.  相似文献   
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29.
A 51 -year-old woman with mixed growth hormone (GH) cell-prolactin (PRL) cell pituitary adenoma is presented. She had clinical signs due to hypersecretion of GH and PRL. Resected tissue was studied immunohistochemically and morphologically. The serial sections revealed that GH and α-subunit were co-localized in most cells, while GH and PRL were localized in different cells.  相似文献   
30.
A case of nonfunctioning parathyroid carcinoma in a 69-year-old female has been studied by light and electron microscopy. The tumor, located on the left side of the anterior neck, was well encapsulated by connective tissue but showed invasion to the capsule and to the thyroid. The tumor cells exhibited a trabecular arrangement surrounded by capillary networks but focally showed several ductal structures. They were polygonal in shape, had a large nucleus showing frequent mitosis and poor cytoplasm containing glycogen. Some tumor cells had clear and abundant cytoplasm, and resembled water-clear cells of the parathyroid. Immunohistochemically, no thyroglobulin was demonstrated in the tumor tissue. Electronmicroscopically, the tumor cells with high N/C ratio contained poorly developed cell organelles and abundant glycogen particles. They were poor in secretory granules and had no conglomeration of lipid. Desmosomes and tonoflbrils were observed. The ratio of the reported number of nonfunctioning parathyroid carcinoma to that of functioning one in Japan was compared with that in western countries. No difference of the ratio was found between these two, when identical criteria were employed.  相似文献   
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