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71.
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   
72.
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   
73.
Two rare variants of HLA-A locus antigens, tentatively called HLA-A2K and HLA-A9HH, were serologically identified in the Japanese population. A2K and A9HH showed short reaction patterns of a series of anti-A2 and anti-A9 sera, respectively. The latter variant also reacted with some anti-A2 sera. Nucleotide sequences of full-length cDNAs for A2K and A9HH were determined. The results revealed that both antigens are encoded by previously undescribed alleles. The nucleotide sequence of the allele for A2K was identical to that of A*0207 except for a single nucleotide difference in exon 3. The nucleotide sequence of the allele for A9HH was identical to that of A*2402 except for two nucleotides in exon 2. These two nucleotides are shared by all the reported A2 alleles. These sequencing results the allele for A9HH were consistent with the serological cross-reactivity of A9HH with some anti-A2 sera.  相似文献   
74.
75.
Malignant histiocytosis. A report of three cases.   总被引:1,自引:0,他引:1  
Three cases of malignant histiocytosis were immunohistochemically studied. The cases included the following three patients: a 38-year-old man, a 44-year-old man, and a girl aged 5 years 9 months. All three patients died within 3 months of hospitalization. They had a high fever (temperature over 38.5 degrees C), lymph node swelling, hepatosplenomegaly, and pancytopenia. Blastoid and hemophagocytic cells proliferated in the bone marrow and lymph nodes, especially in the sinuses of the latter. We diagnosed malignant histiocytosis in the three cases based on clinical features, extremely poor prognoses, and the morphologic features and growth pattern of blastoid and hemophagocytic cells. Blastoid and hemophagocytic cells expressed phenotype Mac-387+/KP1+/lysozyme+/polyclonal CD3+. The Mac-387 and KP1 antigens and lysozyme are markers for monocytes/macrophages, and polyclonal CD3 is a marker for T lymphocytes. Therefore, we suggest that a certain number of cases of malignant histiocytosis have a biphenotypic nature, namely, the T cell and macrophage, although many cases of malignant histiocytosis have been reported as expressing only T-lymphocyte antigens.  相似文献   
76.
Saliva contains a number of proteins and glycoproteins that protect oral tissues, but little is known about the role of human saliva in innate immunity. Here we showed that human major salivary gland cells constitutively expressed a bacterial pattern recognition receptor, CD14, by immunohistochemistry. Human salivary gland cells in culture express CD14 mRNA and a 55-kDa CD14 protein in, but not on the cells, and secrete a soluble form with the same molecular mass. Human whole saliva contains a 55-kDa CD14, and the concentration of parotid saliva was 10-fold higher than whole saliva, which is comparable to that of serum CD14. Levels of CD14 in unstimulated whole and parotid saliva were unchanged before and after a meal and between unstimulated and stimulated saliva, indicating that saliva CD14 is constitutively secreted into the oral cavity. In contrast, lipopolysaccharide (LPS)-binding protein was below the detectable level. The saliva CD14 is functionally active in that it mediated the activation of CD14-lacking intestinal epithelial cells by LPS in a Toll-like receptor 4-dependent manner. These results suggested that saliva CD14 is important for the maintenance of oral health and possibly intestinal homeostasis.  相似文献   
77.
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT.  相似文献   
78.
A case of the syndrome of sea-blue histiocyte is presented in a 53-year-old Japanese woman, which is the first recorded case in Japan. The patient had hepatosplenomegaly, bleeding manifestations, mild thrombocytopenia, fatty metamorphosis and cirrhosis of the liver, as well as abnormal serum lipid profiles. Her parents were consanguineous and her maternal grandmother with hepatomegaly died of hepatic failure. Histologically, peculiar histiocytes containing numerous, intracytoplasmic sea-blue stained granules on May-Giemsa stain were demonstrated in biopsy materials of the bone marrow, lymph node and liver. The sea-blue granules in these histiocytes proved to have histochemical staining characteristics of lipogenic ceroid-like pigment. Ultrastructurally, these granules showed membrane-bound, pleomorphic inclusions of heterogeneous nature, including electron-dense amorphous or variegatedly osmiophilic, frequently laminated materials. Enzyme cytochemically, localization of acid phosphatase activity was demonstrated in and around the intracytoplasmic inclusions. With regard to the pathogenesis of the sea-blue histiocytes in this case, it may be suggested that the existence of the abnormality in lipid metabolism plays an important role in intralysosomal ceroidogenesis in these histiocytes.  相似文献   
79.
In the present study, 13 cases of a peculiar gall-bladder granuloma characterized by marked proliferation of ceroid-fllled brown histiocytes were pathomorphologically, histochemically and ultrastructurally examined to define the pathologic features of such a lesion previously undescribed in the literature. The lesion grossly showed a granulomatous appearance of yellow brown to dark brown color developing in the wall of gall-bladder. Histologically, there was proliferation of histiocytes containing abundant brown pigment granules In their cytoplasm. The pigment granules proved to have staining characteristics closely resembling those of lipogenic ceroid-like pigment. Ultrastructurally, these granules showed membrane-bound, pleomorphic osmiophilic inclusions of heterogenous materials. With regard to the pathogenesis of this granuloma, it may be suggested that lipid components of bile juice, particularly unsaturated fatty acids and phospholipids, play an Important role as a source of ceroidogenesis In the proliferating histiocytes.  相似文献   
80.
Postsynaptic potentials (PSPs) with long latencies were evoked in cat hindlimb motoneurons by stimulation of the distal stump of a cut ventral root. Measurements of their latency and the threshold in the responsible afferent fibers showed that they were produced mainly by the activity of the unmyelinated fibers in the ventral root that enter the spinal cord through the dorsal root. Patterns of PSPs evoked in flexor and extensor motoneurons by ventral root stimulation were similar to those observed in the flexion reflex.  相似文献   
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