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31.
Hematopoietic neoplasm coexpressing CD4 and CD56 includes a subset of acute myeloid leukemia with myelomonocytic differentiation, plasmacytoid monocyte tumor, and other immature hematopoietic neoplasms of undefined origin. Herein, we report a CD4+CD56+CD68+ hematopoietic tumor that was thought to be a tumor of plasmacytoid monocytes. This case is unique in the absence of accompanying myelomonocytic leukemia and the faint expression of cCD3 on the tumor cells. The patient was a 22-yr old man presented with multiple lymphadenopathy and an involvement of the bone marrow. Tumor cells were large and monomorphic with an angulated eosinophilic cytoplasm of moderate amount. Nuclei of most tumor cells were eccentric and round with one or two prominent nucleoli. Rough endoplasmic reticulum was prominent in electron microscopic examination. Tumor cells expressed CD4, CD7, CD10, CD45RB, CD56, CD68, and HLA-DR and were negative for CD1a, CD2, sCD3, CD5, CD13, CD14, CD20, CD33, CD34, CD43, CD45RA, TIA-1, S-100, and TdT. cCD3 was not detected in the immunostaining using paraffin tissue, but was faintly expressed in flow cytometry and immunostaining using a touch imprint slide. T-cell receptor gene rearrangement analysis and EBV in situ hybridization showed negative results. Cytochemically, myeloperoxidase, Sudan black B, and alpha naphthyl butyrate esterase were all negative.  相似文献   
32.
BACKGROUND: We recently described patients with soybean allergy mainly mediated by cross-reactivity to birch pollen allergens. A majority of those patients were reported to have peanut allergy. OBJECTIVE: We sought to study the occurrence of peanut allergy in patients allergic to birch pollen and characterized the Bet v 1-homologous peanut allergen Ara h 8. METHODS: Recombinant Ara h 8 was cloned with degenerated primers and expressed in Escherichia coli. Nine Swiss and 11 Dutch patients with peanut and birch pollen allergy and a positive double-blind, placebo-controlled food challenge result to peanut were investigated for IgE reactivity to birch pollen and purified peanut allergens and cross-reactivity between birch and peanut. Ara h 8 stability against digestion and roasting was assessed by means of RAST inhibition. The IgE cross-linking potency of Ara h 8 was tested on the basis of basophil histamine release. RESULTS: During double-blind, placebo-controlled food challenge, all patients experienced symptoms in the oral cavity, progressing to more severe symptoms in 40% of patients. CAP-FEIA detected recombinant (r) Ara h 8-specific IgE in 85%. IgE binding to Ara h 8 was inhibited by Bet v 1 in peanut extract immunoblotting and in RAST inhibition. In EAST inhibition recombinant rAra h 8 inhibited IgE binding to peanut in 4 of 7 tested patient sera. Antipeanut response was dominated by Ara h 8 in 12 of 17 tested patients. Furthermore, our results demonstrate a low stability of Ara h 8 to roasting and no stability to gastric digestion. Basophil histamine release with rAra h 8 was more than 20% in 5 of 7 tested sera. CONCLUSIONS: Peanut allergy might be mediated in a subgroup of our patients by means of cross-reaction of Bet v 1 with the homologous peanut allergen Ara h 8.  相似文献   
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34.
Atopic dermatitis is a common chronic, relapsing, pruritic ecematous skin condition with a predilection for the flexural areas and occurs in patients with a personal or family history of atopy. The aim of this study is to describe the profile of atopic dermatitis seen at the National Skin Centre in Singapore. A retrospective chart review was conducted of all the patients with atopic dermatitis seen during the first six months of 1994. There were 492 patients whose ages ranged from one month to 74 years with an equal sex ratio. The prevalence was 2%. The onset of the disease occurred before the age of 10 years in 61.2% of patients. In 13.6% of the patients, the onset was after the age of 21 years. Two hundred and fifty-four patients (52%) had "pure" atopic dermatitis without concomitant respiratory allergies. Two hundred and thirty-eight patients (48%) suffered from a "mixed" type, with 23% having allergic rhinitis, 12% having asthma and 13% having both asthma and allergic rhinitis. Two hundred and thirty-one patients (47%) had at least one first-degree family member with atropy: atopic dermatitis (17%), asthma (15%) and allergic rhinitis (15%). Most of the patients, 416 (84.5%), had subacute eczema at presentation. Ichthyosis vulgaris was present in 38 patients (8%) and pityriasis alba in 13 patients (3%). The most common infective complication was bacterial infection (impetiginized eczema, folliculitis, cellullitis) present in 95 patients (19%) followed by viral infections (eczema herpeticum, viral warts and molluscum contagiosum) in 17 patients (3%). Allergies were noted in 43 patients (9%) based on the history given. The most common was drug allergies (penicillin and co-trimoxazole) in 28 patients followed by food allergies in 11 patients. Common aggravating factors reported include heat, sweating, stress, thick clothing and grass intolerance. Most patients could be controlled with a fairly simple regimen of moisturizers, topical steroids and antibiotics for acute flares. Short courses of systemic steroids were used in 78 patients (16%). Three patients were treated with phototherapy, Two on UVAB and one on PUVA. The pattern of atopic dermatitis in Singapore is similar to that reported in the Western literature except for a lower prevalence and a significant proportion of adult onset atopic dermatitis.  相似文献   
35.
Li SS  Xue WC  Khoo US  Ngan HY  Chan KY  Tam IY  Chiu PM  Ip PP  Tam KF  Cheung AN 《Histopathology》2005,46(3):307-313
AIMS: To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues. METHODS AND RESULTS: Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50). CONCLUSIONS: In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients.  相似文献   
36.
AIMS: To investigate whether prognosis in micropapillary urothelial carcinoma is related to the proportion of the micropapillary component (MPC), and to identify the immunohistochemical features of MPC. METHODS AND RESULTS: This study presents a clinicopathological analysis of 20 patients with micropapillary urothelial carcinoma of the bladder with cystectomy specimens for evaluation. Tumours were stratified on the extent of MPC: focal, <10%; moderate, 10-50%; extensive, >50%; and this was correlated with tumour stage and prognosis. Sixteen males and four females were aged 56-81 years (mean 69 years). All cases had high-grade morphology in the micropapillary carcinoma and typical urothelial carcinoma. All cases with extensive MPC (n = 4) were of a high pathological stage (pT3 or pT4) and died of disease (DOD) or other causes. Eighty percent with moderate MPC (eight of 10 cases) were pT3 or pT4 and 50% DOD or are alive with disease. Eighty-four percent with focal MPC (five of six cases) were pT1 or pTa. In high-stage cases, the most invasive component was MPC. High-stage cases had an 85% risk of being advanced at presentation with micropapillary carcinoma. All pT2 or lower stage cases had micropapillary carcinoma on prior transurethral resections of bladder tumour (TURB). High-stage carcinomas had 30% and 54%, respectively, of surface MPC and urothelial carcinoma in situ, in comparison with 85% and 28% in lower stage carcinomas. Immunohistochemical staining was similarly positive in MPC and typical urothelial carcinoma with cytokeratin (CK)7, CK20, epithelial membrane antigen, carcinoembryonic antigen and cytokeratin 34betaE12. CA125 staining was seen only in MPC in 43% of cases. CONCLUSIONS: Micropapillary urothelial carcinoma is a high-grade carcinoma in which the prognosis is related to the proportion and location of the MPC. Cases with moderate or extensive MPC are at high risk of being advanced at presentation. Cases with <10% MPC and surface MPC have a high chance of detection at an early stage. The morphology and immunohistochemical profile of the MPC suggest that it is a form of glandular differentiation in urothelial carcinoma.  相似文献   
37.
Hormone-independent growth and invasiveness represent phenotypic properties acquired during early progression of breast cancer. We compared human mammary adenocarcinoma cells, MCF-7, which are estrogen-dependent and poorly metastatic, with the estrogen-independent and highly metastatic subline, MCF7/LCC1, with regard to expression of tissue-degrading factors of the matrix metalloproteinase (MMP)-and urokinase (uPA)-dependent degradative pathways, as well as for their in vitro invasive properties. Both cell lines showed low constitutive mRNA expression of the MMP inhibitor TIMP-1. Baseline expression of TIMP-2 mRNA was also very low in MCF-7 cells, whereas the MCF7/LCC1 level was much higher (~10- fold). Furthermore, both cell lines revealed low constitutive capacity to migrate in an in vitro invasion assay. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 nM) induced the mRNAs for TIMP-1 as well as for MMP-1, MMP-9, the uPA receptor, and the uPA inhibitor PAI-1, am ongst which only the responses of MMP-9 and PAI-1 were cell-specific. The mRNA levels of MMP-9 and PAI-1 were ~10-fold and ~15-fold higher in MCF7/LCC1 cells compared to MCF-7 cells. The secretion of immuno-reactive PAI-1 was considerably elevated (. 20-fold) in TPA-treated MCF7/LCC1 cells, whereas the TPA-dependent level of 92-kDa MMP-9 was only ~2-fold higher in MCF7/LCC1 cells than in MCF-7 cells. In both cell lines treatment with TPA was associated with an increase (~10-fold) in in vitro migration, which in the MCF7/LCC1 cells was significantly attenuated by a reconstituted basement membrane extract (Matrigel). These data suggest that TPA-responsive in vitro invasive properties that are probably associ-ated with PAI-1 expression may co-vary with progression from hormone-dependent to -independent breast cancer. © Rapid Science 1998  相似文献   
38.
Diets enriched with fat, especially unsaturated fat, promote experimental pancreatic carcinogenesis, but little is known of the effects of individual fatty acids. The effect of stearic and oleic acid on pancreatic fatty acids and atypical acinar cell nodules (preneoplastic lesions) was studied in 14-day-old weanling male Leeds strain rats (n = 60) given the carcinogen azaserine. Rats were allocated to one of six groups: untreated controls (n = 10), 20% stearic acid diet (n = 10), 20% oleic acid diet (n = 10), carcinogen alone (n = 10), carcinogen plus 20% stearic acid diet (n = 10) or carcinogen plus 20% oleic acid diet (n = 10). Azaserine was administered by intraperitoneal injection in a dose of 30 mg/kg at 2, 3 and 4 weeks of age. When total lipid extracts of pancreas were examined, there was an increase in stearic acid in the stearic acid fed group and an increase in oleic acid in the oleic acid fed group, irrespective of carcinogen treatment. The relative content of all other pancreatic fatty acids was suppressed by feeding oleic acid. At 26 weeks, the number and volumetric indices of pancreatic atypical acinar cell nodules was increased only in rats given azaserine and oleic acid. The enhancing effect of oleic acid on pancreatic carcinogenesis may be associated with pancreatic fatty acid changes.  相似文献   
39.
BACKGROUND: The p21WAF1/CIP1 gene mediates growth arrest by inhibiting G1 cyclin dependent kinases and has been considered as a downstream effector of the tumour suppressor gene p53. AIM: To analyse the role of p21WAF1/CIP1 in gestational trophoblastic disease. METHODS: The immunohistochemical expression of p21WAF1/CIP1 gene was measured in 33 placentas, 28 partial hydatidiform moles, 54 complete hydatidiform moles, and 13 choriocarcinomas in paraffin wax embedded tissue. The results were correlated with p53 (DO7) and Ki67 (MIB1) immunoreactivity as well as clinical progress. RESULTS: p21WAF1/CIP1 immunoreactivity was found predominantly in the nuclei of the syncytiotrophoblasts. p21WAF1/CIP1 protein expression correlated with gestational age in normal placentas (p = 0.0001) but not in hydatidiform moles (p = 0.89). Complete hydatidiform moles and choriocarcinomas had a significantly higher p21WAF1/CIP1 expression compared with normal placentas and partial hydatidiform moles (p < 0.001); there was no difference between placentas and partial hydatidiform moles. No correlation between p21WAF1/CIP1 expression and either the proliferation (Ki67) index (p = 0.34) or p53 protein accumulation (p = 0.68) was demonstrated. There was no significant difference (p > 0.05) in p21WAF1/CIP1 expression between the 17 patients who developed persistent gestational trophoblastic disease and those who did not. CONCLUSIONS: This study suggests that p21WAF1/CIP1 expression in trophoblastic disease may be induced by a p53 independent pathway. The proliferative activity of gestational trophoblastic diseases might not be determined solely by the control of the cell cycle operated by p21WAF1/CIP1. p21WAF1/CIP1 expression is not an accurate prognostic indicator of gestational trophoblastic disease.  相似文献   
40.
H J Ree  M E Kadin 《Cancer》1985,56(2):333-338
The authors studied the occurrence of peanut agglutinin (PNA)-binding cells in paraffin-embedded specimens of 145 patients with Hodgkin's disease (HD). The staining reaction of lymphocytes was consistently negative. A positive staining reaction was observed in two types of cells: macrophage-histiocytes (M-H), and Reed-Sternberg (R-S) cells and their variants. Diffuse or globular cytoplasmic staining was found in M-H, which was easily distinguished from a unique "cell surface and cytoplasmic" staining pattern of R-S and related cells. Thus defined, M-H were numerous in lymphocyte depletion and mixed cellularity, less common in lymphocyte predominance, and least frequent in the nodular sclerosis type. Numerous M-H correlated with B-symptoms and a poor response to therapy. Among the asymptomatic patients with localized disease at presentation, the presence of large numbers of M-H was associated with a high incidence of relapse within 2 years of therapy. These findings suggest that the number of non-neoplastic M-H in HD may be an important determinant in the clinical presentation and course of disease. Peanut agglutinin staining may be useful for the detection of M-H in routine diagnosis and classification of HD, which has not been feasible by conventional methods.  相似文献   
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