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51.
The authors examined urine specimens from 30 patients with multiple myeloma (MM) to determine the usefulness of cytodiagnostic urinalysis in evaluating such patients. Nine patients had clinical evidence of renal failure. In six of these nine patients (67%), or 20% of all patients, the urine sediment contained unique "MM-casts." These were characterized by a waxy to granular matrix surrounded by reactive, syncytial, giant cells with occasional renal cells embedded in the cast matrix. These casts were not observed in urine specimens from patients with normal renal function. Renal biopsy in two patients with MM-casts confirmed that cytologic diagnosis of "MM-kidney." The patient groups with or without MM-casts were comparable with respect to age, sex, and clinical stage of disease. In contrast, those with MM-casts were more likely to have clinical evidence of renal disease (100% vs. 13%), Bence Jones proteinuria (100% vs. 35%), hypercalcemia (50% vs. 8%), and hyperuricemia (50% vs. 4%). The two groups could not be distinguished reliably by urine physicochemical determinations. However, there were marked differences in the frequency of microscopic abnormalities. All patients with MM-cast formation excreted other pathologic casts as well and had evidence of tubular injury, while five of six had evidence of ischemic necrosis. This compared with 17%, 13%, and 21%, respectively, of those without MM-casts. Thus, cytodiagnostic urinalysis is of value in distinguishing MM-kidney from the numerous other causes of renal failure in patients with MM.  相似文献   
52.
To increase the likelihood of finding genetic variation conferring liability to eating disorders, we measured over 100 attributes thought to be related to liability to eating disorders on affected individuals from multiplex families and two cohorts: one recruited through a proband with anorexia nervosa (AN; AN cohort); the other recruited through a proband with bulimia nervosa (BN; BN cohort). By a multilayer decision process based on expert evaluation and statistical analysis, six traits were selected for linkage analysis (1): obsessionality (OBS), age at menarche (MENAR), and anxiety (ANX) for quantitative trait locus (QTL) linkage analysis; and lifetime minimum body mass index (BMI), concern over mistakes (CM), and food-related obsessions (OBF) for covariate-based linkage analysis. The BN cohort produced the largest linkage signals: for QTL linkage analysis, four suggestive signals: (for MENAR, at 10p13; for ANX, at 1q31.1, 4q35.2, and 8q13.1); for covariate-based linkage analyses, both significant and suggestive linkages (for BMI, one significant [4q21.1] and three suggestive [3p23, 10p13, 5p15.3]; for CM, two significant [16p13.3, 14q21.1] and three suggestive [4p15.33, 8q11.23, 10p11.21]; and for OBF, one significant [14q21.1] and five suggestive [4p16.1, 10p13.1, 8q11.23, 16p13.3, 18p11.31]). Results from the AN cohort were far less compelling: for QTL linkage analysis, two suggestive signals (for OBS at 6q21 and for ANX at 9p21.3); for covariate-based linkage analysis, five suggestive signals (for BMI at 4q13.1, for CM at 11p11.2 and 17q25.1, and for OBF at 17q25.1 and 15q26.2). Overlap between the two cohorts was minimal for substantial linkage signals.  相似文献   
53.
Stromal cells direct local differentiation of regulatory dendritic cells   总被引:11,自引:0,他引:11  
Svensson M  Maroof A  Ato M  Kaye PM 《Immunity》2004,21(6):805-816
CD11c(hi) dendritic cells (DC) play an essential role during the initiation of cell-mediated immunity. Recently, CD11c(lo)CD45RB(hi) DC with regulatory properties have been described. However, the origins of regulatory DC are poorly understood. Here, we show that spleen-derived stromal cells promote selective development of CD11c(lo)CD45RB(+) IL-10-producing regulatory DC from lineage-negative c-kit(+) progenitor cells. These DC have the capacity to suppress T cell responses and induce IL-10-producing regulatory T cells in vitro and to induce antigen-specific tolerance in vivo. Furthermore, stromal cells from mice infected with Leishmania donovani more effectively supported differentiation of these highly potent regulatory DC. The ability of tissue stromal cells to direct the development of DC with a regulatory phenotype thus provides a new mechanism for local immune regulation.  相似文献   
54.
Experimental analysis of the annotation of promoters in the public database   总被引:4,自引:0,他引:4  
The ability to identify and examine promoter elements is important to researchers who wish to understand how gene expression is regulated in normal and pathological states. Unfortunately, the number of human promoters that have been directly experimentally defined is small. In order to determine if promoter sequences can be identified by simply aligning mRNA and genomic sequences, we have used a reporter gene assay to assess the promoter activity of the immediate 5' region flanking 38 mRNAs mapping to chromosome 21. For comparison, we have measured the activities of 19 sequences not thought to be promoters and 39 sequences taken from the Eukaryotic Promoter Database. Our results suggest that alignment of reference mRNAs to genomic sequence allows promoters to be identified for at least 75% of genes. These data provide the first empirical evidence that the current state of annotation of the genome is sufficient to allow molecular geneticists to correctly identify promoter sequences for most genes for which reference mRNA and genomic sequences are available.  相似文献   
55.
BACKGROUND: The Shipman Inquiry recommended mortality rate monitoring if it could be 'shown to be workable' in detecting a future mass murderer in general practice. AIM: To examine the effectiveness of cumulative sum (CUSUM) charts, cross-sectional Shewhart charts, and exponentially-weighted, moving-average control charts in mortality monitoring at practice level. DESIGN OF STUDY: Analysis of Scottish routine general practice data combined with estimation of control chart effectiveness in detecting a 'murderer' in a simulated dataset. METHOD: Practice stability was calculated from routine data to determine feasible lengths of monitoring. A simulated dataset of 405,000 'patients' was created, registered with 75 'practices' whose underlying mortality rates varied with the same distribution as case-mix-adjusted mortality in all Scottish practices. The sensitivity of each chart to detect five and 10 excess deaths was examined in repeated simulations. The sensitivity of control charts to excess deaths in simulated data, and the number of alarm signals when control charts were applied to routine data were estimated. RESULTS: Practice instability limited the length of monitoring and modelling was consequently restricted to a 3-year period. Monitoring mortality over 3 years, CUSUM charts were most sensitive but only reliably achieved >50% successful detection for 10 excess deaths per year and generated multiple false alarms (>15%). CONCLUSION: At best, mortality monitoring can act as a backstop to detect a particularly prolific serial killer when other means of detection have failed. Policy should focus on changes likely to improve detection of individual murders, such as reform of death certification and the coroner system.  相似文献   
56.
AIM: We describe a case of Aggressive Digital Papillary Adenocarcinoma, a rare skin neoplasm with acral location. RESULTS: The patient, a 66 year old man, presented with an ulcerated mass of the fifth toe of the left foot, 4.4 cm in size. Histologically the tumour was characterized by a solid-cystic structure, with extensive papillary component, comedo necrosis and focal eccrine differentiation. Immunohistochemistry showed diffuse positivity for cytokeratins AE1/AE3 and 7, and, focal staining for Muscle Specific Actin, Vimentin and EMA. Chest CT scan showed the presence of a single pulmonary node, whose cytological features were consistent with a metastatic disease. CONCLUSIONS: The clinico-pathological features of the present are similar to those previously reported in the literature and confirms the aggressive nature of this neoplasm.  相似文献   
57.
For the presentation of Leishmania promastigotes to polyclonal CD4+ T cells, a processing period within activated macrophages of 3-4 h is required. Presentation can be inhibited by both chloroquine and brefeldin A (BFA), the latter implicating a requirement for newly synthesized MHC class II molecules. This inhibition is both reversible and specific, in that BFA did not inhibit mixed lymphocyte reaction stimulation by these infected macrophages. Immunogold labeling demonstrated that class II was associated with the parasite-containing phagolysosome. The level of class II was not significantly altered in BFA-treated cells in the time period studied, suggesting that antigen may exist the phagolysosome and interact with class II in another cellular compartment.  相似文献   
58.
59.
Processing of antigen for recognition by class II-restricted CD4+ T cells occurs within acidic compartments of the antigen-presenting cell. The exact nature of this compartment has yet to be precisely defined, however, but may vary depending upon the cell type studied and the antigen used. The acidic compartments of macrophages are also responsible for the degradation of ingested micro-organisms and play host to others which are adapted to an intracellular existance. To determine whether the phagolysosome (PL) formed in activated macrophages after ingestion of Leishmania parasites is also a site for entry of antigen into the class II presentation pathway, we have used the approach of genetic transformation. Hence, Leishmania were transfected with the genes for the protein antigens ovalbumin (OVA) and β-galactosidase (β-gal) and after infection were able to deliver these antigens specifically into the PL. Delivery of antigen to this site resulted in the ability of infected macrophages to present these antigens to antigen-specific CD4+ T cells. After taking into account the absolute levels of antigen uptake by macrophages, a 4-h processing period for OVA delivered by this or a soluble route led to equivalent levels of T cell activation. Unlike macrophages pulsed with soluble OVA, those with PL-targeted OVA still retained the ability to stimulate T cells after a 24-h processing period. This enhanced lifespan of antigen in macrophages corresponded to the kinetics of degradation of the parasite, suggesting slow release of antigen into the processing pathway. β-gal presentation from the PL was tenfold less efficient under the same conditions. In addition to providing the first information on antigen processing in a protozoan PL, these studies highlight the usefulness of genetically transformed parasites for these types of studies.  相似文献   
60.
In recent years, fine-needle-aspiration biopsies (FNA) have been widely used in the evaluation of renal masses, with false-positive FNA data being very uncommon. We present a case report of a 76-yr-old man with a 16-cm renal cyst and what was interpreted as an isolated calcified mural nodule. Following drainage of the main cyst fluid, FNA biopsy showed atypical cell clusters thought to be positive for malignancy. Subsequent surgery failed to disclose either a residual mural nodule or evidence of malignancy. Immunoperoxidase studies performed on both the cell block and actual cyst wall suggested that the abnormal cells were histiocytes. The diagnostic pitfalls of this case, along with a review of pertinent literature, are discussed. Diagn Cytopathol 1994; 11:380–384. © 1994 Wiley-Liss, Inc.  相似文献   
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