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61.
Monocytes in a familial monocyte disorder, a recently recognized primary immunodeficiency syndrome, with impaired phagocytic functions were studied for their ability to produce interleukin 1 (IL-1) as well as the surface property. Monocytes from two children (siblings) with the disorder possessed CD11b, CD13, CD14, CD33, Ia and LFA-1/Mac-1/p150,95 beta subunit antigens as determined by flow cytometry. Electron microscopic cytochemistry showed that the monocytes had surface glycoproteins reactive with four representative lectins. The IL-1 production by monocytes was assayed in the two patients and compared with that in six children with primary immunodeficiency syndromes and some monocyte abnormalities; three had congenital neutropenia, two had hyper-IgE syndrome, and one had defective monocyte chemotaxis. Monocyte culture supernatants were prepared with stimulation by lipopolysaccharide or silica, and their IL-1 activity was measured by the mouse thymocyte-proliferation assay. The patients' monocytes were defective in IL-1 production: the values were less than 1.0% of the control monocyte values (n = 12) and were in contrast with those of congenital neutropenia monocytes of 186.2% to 204.3%. These results demonstrate a familial monocyte disorder which is characteristic among the immunodeficiency syndromes with regard to the defective IL-1 production and the impaired phagocytic functions.  相似文献   
62.
Dedifferentiated adenoid cystic carcinomas are a recently defined, rare variant of adenoid cystic carcinomas characterized histologically by two components: conventional low-grade adenoid cystic carcinoma and high-grade "dedifferentiated" carcinoma. We examined six cases and analyzed their clinicopathologic profiles, including immunohistochemical features and p53 gene alterations. The 6 patients (3 men and 3 women) had a mean age of 46.8 years (range, 34-70 y). The mean size of the tumors was 3.5 cm (range, 1.7-6 cm). The submandibular gland, maxillary sinus, and nasal cavity were involved in 2 cases each. Postoperatively, 5 patients had local recurrence and 5 developed metastatic disease. Five patients died of disease at a mean of 33.7 months after diagnosis (range, 6-69 mo), and one other was alive with disease at 60 months. Histologically, the conventional low-grade adenoid cystic carcinoma component of the tumors consisted of a mixture of cribriform and tubular patterns with scant solid areas. The high-grade dedifferentiated carcinoma component was either a poorly differentiated adenocarcinoma (4 cases) or undifferentiated carcinoma (2 cases). Three tumors were studied immunohistochemically. Myoepithelial markers were expressed in low-grade adenoid cystic carcinoma but not in the dedifferentiated component. In 2 cases, diffusely positive p53 immunoreactivity together with HER-2/neu overexpression was restricted to the dedifferentiated component. Loss of pRb expression was demonstrated only in the dedifferentiated component of the 1 other case. The Ki-67-labeling index was higher in the dedifferentiated component than in the low-grade adenoid cystic carcinoma component. Furthermore, molecular analysis of 2 cases demonstrated the loss of heterozygosity at p53 microsatellite loci, accompanied by p53 gene point mutation, only in the dedifferentiated carcinoma component of 1 case, which was positive for p53 immunostaining. These results indicate that dedifferentiated adenoid cystic carcinoma is a highly aggressive tumor. Because of frequent recurrence and metastasis, the clinical course is short, similar to that of adenoid cystic carcinomas with a predominant solid growth pattern. Limited evidence suggests that p53 abnormalities in combination with HER-2/neu overexpression or loss of pRb expression may have a role in dedifferentiation of adenoid cystic carcinoma.  相似文献   
63.
Summary Nineteen hybridomas producing monoclonal antibodies (MAbs) against the structural proteins of strain 58–17, a subgroup B field strain of respiratory syncytial virus (RSV) isolated in Japan, were obtained by fusion of X 63 myeloma cells with spleen cells from BALB/c mice immunized with the virus-infected HEp-2 cells. Seven clones were found to produce antibodies against the fusion protein (F), five against the large glycoprotein (G), five against the nucleoprotein (NP) and two against the 22k protein by radioimmunoprecipitation assay. By competitive binding assay with the MAbs, at least seven, two, three and one epitopes were defined on the F, G, NP and 22k protein components of subgroup B strain, respectively. Of these epitopes, three, two and one epitopes on the F, G and NP components were different from subgroup A strain, respectively. Fifty-three other field strains of subgroup B isolated in Sapporo, Japan, during nine epidemic years from 1980 to 1989, were examined for reactivity with the MAbs by ELISA. Different reactivity to one anti-NP antibody suggested that the 53 strains can be divided into three groups (B-a: 26 strains, B-b: 26 strains, and one other strain). The dominant strain prevailing during the 1984 to 1988 epidemic years had changed from B-a to B-b. All of the 53 subgroup B strains reacted similarly with the other 18 MAbs.  相似文献   
64.
A 56-year-old Japanese man underwent total gastrectomy with lymph-node dissection for a gastric tumor. In the oral rim of the excised large ulcerated tumor, a small nodular mass demonstrated a unique histology of a carcinosarcoma composed of more than three distinctive components. A major part of the large ulcerated tumor tissue consisted of conventional tubular adenocarcinoma, with the coincidental focal distribution of solid cell nests of poorly differentiated or neuroendocrine cell (small cell) carcinoma. Sarcoma cells were another of the constituents of the small nodular tumor with atypical spindle-shaped cells. All the excised lymph-node metastasis demonstrated the histology of tubular adenocarcinoma. In the sarcoma cells, many of the lineage-specific immunohistochemical markers were negative. Only vimentin was positive. Electron microscopy revealed that the neuroendocrine cell carcinoma contained cells with abundant small aggregations of neurosecretory-type granules in their cellular cytoplasm. Primitive cellular junctions and incomplete basal lamina were seen in the sarcoma cells. No transitional or hybrid-type cells were seen between carcinoma and sarcoma cells. The interfaces between the cancer cell nests and the proliferation of sarcoma cells are clearly discerned. It was speculated that the unique histology of carcinosarcoma might have progressed from the conventional type of pre-existing advanced tubular adenocarcinoma.  相似文献   
65.
Intrahepatic biliary tree with either florid duct lesions or a moderate to severe degree of the duct loss in four livers with chronic hepatic diseases other than primary biliary cirrhosis were studied with histometric and serial section observations. Florid duct lesions, distributed segmentally in the liver, were found in one case with incomplete septal cirrhosis and one case with idiopathic portal hypertension. The florid duct lesions including marked plasma cell infiltration and occasional periductal granulomas, were not associated with any bile duct loss in the two cases. The duct lesions were reversible in one case during a long clinical course. On the other hand, a moderate to severe bile duct loss with biliary epithelial degeneration and necrosis was associated with no or little periductal inflammatory cell infiltration in one other case with chronic intrahepatic cholestasis, probably drug-induced, and in one case with idiopathic portal hypertension. Although florid duct lesions and bile duct loss were important diagnostic features of primary biliary cirrhosis, one of them was observed to develop independently in severely diseased livers, not consistent with a diagnosis of primary biliary cirrhosis, sclerosing cholangitis or intrahepatic bile duct paucity syndrome.  相似文献   
66.
Even though cigarette smoking has been shown to suppress immune responses in the lungs, little is known about the effect of cigarette smoke components on respiratory infections. In the present study, the effects of cigarette smoke condensate (CSC) on bacterial replication in alveolar macrophages and the immune responses of macrophages to infection were examined. Furthermore, a possible immunotherapeutic effect of epigallocatechin gallate (EGCg), a major form of tea catechins, on the CSC-induced suppression of antimicrobial activity and immune responses of alveolar macrophages was also determined. The treatment of murine alveolar macrophage cell line (MH-S) cells with CSC significantly enhanced the replication of Legionella pneumophila in macrophages and selectively down-regulated the production of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) induced by bacterial infection. The treatment of macrophages with EGCg not only overcame the CSC-induced suppression of antimicrobial activity but also strengthened the resistance of macrophages to infection. EGCg also markedly up-regulated the CSC-suppressed IL-6 and TNF-α production by macrophages in response to infection. The results of exogenous TNF-α treatment and neutralization treatment with anti-TNF-α and anti-gamma-interferon (IFN-γ) antibodies and the determination of IFN-γ mRNA levels indicate that CSC-suppressed macrophages can be activated by EGCg to inhibit L. pneumophila growth by up-regulation of TNF-α and IFN-γ production. Thus, this study revealed that CSC selectively alters the immune responses of macrophages to L. pneumophila infection and leads to an enhancement of bacterial replication in macrophages. In addition, the tea catechin EGCg can diminish such suppressive effects of CSC on alveolar macrophages.  相似文献   
67.
Step-sections of 96 whole kidneys from 50 chronic hemodialysis patients were subjected to a histopathological and quantitative investigation with regard to the development of renal neoplastic lesions. The range of hemodialysis duration was from 1 to 222 months. A total of 349 renal cell adenomas were found in 41 cases (82%). They were commonly multiple and present bilaterally. Renal cell carcinomas were evident in four cases (8%), with hemodialysis durations of 54, 57, 112 and 222 months. The incidence of adenomas increased in a hemodialysis duration-dependent manner, indicating a high risk of renal cell tumor development in chronic hemodialysis patients. Furthermore, acquired cystic disease of the kidney (ACDK) was also observed in 12 cases (24.0%), where the mean hemodialysis period was 143.4 ± 48.0 months. This value was significantly longer than that of non-ACDK cases (P < 0.001). There was, however, no clear relationship between the appearance of ACDK and renal cell tumors. The present results underline the necessity for attention to possible neoplasia of the kidney in patients on long-term hemodialysis.  相似文献   
68.
The case to be reported is that of a 72-year-old woman with isolated adrenocorticotropic hormone (ACTH) deficiency, who complained of anorexia and generalized malaise. The secretions of human growth hormone(HGH), prolactin (PRL), luteinizing hormone (LH), follicle stimulating hormone (FSH), and thyroid stimulating hormone (TSH) were all within normal limit. In spite of the extremely low level of Cortisol, the plasma level of AGTH would not rise sufficiently, but a marked response of Cortisol to AGTH stimulation was recognizaed. The postmortem examination revealed a decrease In basophilic or PAS-positive cells of the anterior pituitary gland which also showed a selective loss of AGTH-secreting cells over immunohistochemical study. Electron microscope could easily visualize somatotroph, mammotroph, thyrotroph, FSH- and LH-gonadtroph, but corticotroph was difficult to be discerned. Adrenocortical cells demonstrated atrophy and degeneration, for which the zona fasciculata and zona reticularis were narrowed. The zona glomerulosa was slightly enlarged In width.  相似文献   
69.
Using the plasma membrane fraction isolated from rabbit liver (RLPM), we detected non-species specific IgG antibody against liver cell surface membrane in the sera from the patients with chronic liver diseases. The sea were treated with dithiothreitol and iodoacetamide, and absorbed with sufficient amount of actin isolated from rabbit striated muscles. The antibody was detected by incubation of RLPM with the treated and absorbed sera and subsequent determination of IgG bound to RLPM by 125I-staphylococcal protein A. It was found mainly in the patients with autoimmune hepatitis (12 of 28) and liver cirrhosis (eight of 24). It occurred more frequently in HBsAg negative liver cirrhosis than in HBsAg positive forms (six of 13 vs two of 11). The frequency of the antibody was low in chronic hepatitis except autoimmune hepatitis, and primary biliary cirrhosis. Thus the antibody against RLPM was an immunological marker of autoimmune hepatitis and HBsAg negative liver cirrhosis. The occurrence did not correlate with those of anti-smooth muscle antibody, anti-nuclear antibody and anti-mitochondrial antibody. In two cases of autoimmune hepatitis, the antibody against RLPM decreased with clinical improvement induced by corticosteroids.  相似文献   
70.
In the present study, small volumes of plasma were used for the measurement of bromvalerylurea (BVU), its metabolite, 3-methylbutyrylurea (MVU), and bromide in carbon tetrachloride (CCl4)-treated rats by HPLC-UV and energy dispersive X-ray spectrometry. A liquid-liquid extraction system was also investigated. BVU and MVU were extracted from 100 microl plasma samples in a single-step involving deproteination with 1 M hydrochloric acid using ethenzamide as internal standard. Samples were separated by HPLC in an acetonitrile-8 mM potassium dihydrogenphosphate buffer (35:65, v/v) mobile phase at a flow-rate of 0.4 ml/min on a 15 cm octadecylsilyl column at room temperature. Analytes were detected at a wavelength of 210 nm. The limits of quantitation for BVU, MVU and bromide are 0.1, 0.1 and 50 microg/ml, respectively. The intra-day accuracies over the range of concentrations were 95.8 to 121.1%, 97.2 to 119.7% and 96.2 to 105.8% for BVU, MVU and bromide, respectively. The inter-day accuracies were 97.7 to 115.1%, 98.3 to 111.6% and 98.3 to 102.9% for BVU, MVU and bromide, respectively. The absolute recoveries using tert.-butyl methyl ether are 96-98% for BVU and 95-98% for MVU. The decline in the plasma concentrations of BVU in olive oil-treated rats fitted a one-compartment model and the plasma MVU level reached a peak at around 1.5-2 h and then decreased gradually. The elimination of BVU in CCl4 (1 ml/kg)-treated rats was delayed and MVU production was less than that in the olive oil-treated group. However, there was no difference in the plasma levels of bromide between CCl4-treated rats and control rats. rights reserved.  相似文献   
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