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41.
Fluorescence in situ hybridization investigation of cutaneous lesions in acute promyelocytic leukemia. 总被引:1,自引:0,他引:1
Joanna E Wrede Uma Sundram Sabine Kohler Athena M Cherry Daniel A Arber Tracy I George 《Modern pathology》2005,18(12):1569-1576
Cutaneous manifestations of acute promyelocytic leukemia are rare but well documented. Skin biopsies of leukemia can be difficult to confirm using morphology alone, and paraffin section immunophenotyping is not specific in separating acute promyelocytic leukemia from other acute myeloid leukemias involving the skin or inflammatory conditions, such as Sweet's syndrome and all-trans retinoic acid-associated genital ulcers, which may mimic leukemia cutis. Fluorescence in situ hybridization has been shown to be a fast and effective method of detecting the PML/RARA fusion gene characteristic of acute promyelocytic leukemia in fresh blood and bone marrow samples. Fluorescence in situ hybridization has also been demonstrated to be effective in detecting other chromosomal rearrangements in paraffin-embedded tissue. This retrospective study of cutaneous lesions from four patients with acute promyelocytic leukemia evaluates the utility of performing fluorescence in situ hybridization to confirm the presence of cutaneous manifestations of acute promyelocytic leukemia in formalin-fixed, paraffin-embedded skin biopsies. All patients had previous bone marrow findings of acute promyelocytic leukemia with characteristic morphology, immunophenotype, and cytogenetic studies, which detailed the presence of the t(15;17)(q22;q12) rearrangement. Two skin biopsies showed an infiltrate of blastic cells involving the dermis in a diffuse pattern and one biopsy had a perivascular/periadnexal pattern. The fourth case, involving the scrotum, showed a predominant neutrophilic infiltrate diffusely involving the dermis and epidermis with a subset of blastic cells. Nuclei were extracted from core biopsies of the formalin-fixed paraffin-embedded tissue and fluorescence in situ hybridization was performed using a dual color, dual fusion PML / RARA probe. All cases showed evidence of the t(15;17) rearrangement, with 90, 79, 51 and 16% positive signal patterns, each well above background limits. Fluorescence in situ hybridization appears to be a robust technique to detect cutaneous manifestations of acute promyelocytic leukemia in formalin-fixed paraffin-embedded skin biopsies. 相似文献
42.
Preferences towards quinine sulfate (QS) and dextrose (DEX) were tested in purelines and reciprocal crosses of two lines of chickens that had undergone 22 generations of selection for high and low juvenile body weight. Parental line-F1 comparisons provided evidence for non-additive genetic variation for hedonic sensitivity towards QS and DEX, though in opposite directions. Additive genetic variation appeared to influence the preference ratios for both stimuli at super-threshold concentrations. These results are discussed with regard to their evolutionary implications. 相似文献
43.
Schrader TJ Langlois I Soper K Cherry W 《Teratogenesis, carcinogenesis, and mutagenesis》2002,22(6):425-441
Bisphenol A (4,4'-isopropylidenediphenol) is a common component of polycarbonate plastics and epoxy resins. Since bisphenol A-containing plastics and resins have found uses in food-contact items, its potential migration into foodstuffs and possible health consequences have been the focus of many recent studies. However, the potential mutagenic activation of bisphenol A by nitrosylation has received little attention. Incubation of bisphenol A with sodium nitrite under acidic conditions produced a yellow-brown product. When nitrosylated bisphenol A was tested in the Ames Salmonella/microsome assay at 100 ng to 1 mg/plate, dose-dependent increases in mutagenicity were found in both TA98 and TA100 Salmonella strains. These results indicated the presence of a direct-acting mutagenic activity causing both frameshift and base pair mutations, respectively. When compared to colony formation in untreated controls, the addition of rat liver S9 for metabolic activation had little influence on revertant colony formation. Unreacted bisphenol A dissolved in DMSO, acidic buffer, or inactivated nitrosylation solution showed negligible mutagenicity. When the nature of the mutagenic changes was examined using the Ames II trade mark Assay, a variety of base pair changes was found including T:A to A:T - S9, G:C to A:T +/- S9,C:G to A:T +/- S9 and C:G to G:C +/- S9. Bisphenol A also induced frameshift mutations at G:C sites. In addition, the presence of electrophiles was shown by the production of an intensely coloured orange-red product upon incubation of nitrosylated bisphenol A with the nucleophile 4-(4'-nitrobenzyl)pyridine. These findings suggest that migration of bisphenol A into nitrite containing foodstuffs, or its ingestion in the presence of nitrite, could lead to the formation of mutagenic compounds. 相似文献
44.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent. 相似文献
45.
Journal of Prevention - This paper has two goals regarding cultural rigor, defined as privileging cultural ways of knowing and being as a means to achieving health and well-being for future... 相似文献
46.
A technique for eliminating allele specific amplification failure during DNA amplification of heterozygous cells for preimplantation diagnosis 总被引:6,自引:5,他引:6
Advances in techniques of molecular biology have made possible the
amplification of specific genes from single cells. This has a major
clinical application in preimplantation diagnosis of monogenic disorders.
However, the incidence of allele specific amplification failure (allele
drop out) in heterozygous single cells can lead to misdiagnosis and the
transfer of affected embryos. Few studies have been done to investigate the
actual cause of allele drop out, although some investigators have succeeded
in reducing but not eliminating it. Here we report the efficiency of
amplifying both alleles in heterozygous cells lysed according to two
different protocols. A total of 177 heterozygous cells from carriers of
cystic fibrosis (CF) and haemoglobin C (HbC) were lysed using two different
lysis buffers. Interestingly none of the cells that were lysed with sodium
dodecyl sulphate/proteinase K showed any example of allele specific
amplification failure whereas in those lysed by KOH/dithiothreitol it was
present in 17.6 and 4.7% of the CF and HbC cells respectively. Our results
suggest that the phenomenon of allele specific amplification failure is at
least in part dependent on the lysis buffer used.
相似文献
47.
Triantafilou K Triantafilou M Wilson KM Cherry RJ Fernandez N 《Human immunology》1999,60(11):1101-1112
The intracellular and cell-surface heterotypic associations of HLA-DR in the presence and absence of the invariant chain were investigated. Simultaneous confocal microscopy imaging of the Golgi apparatus and HLA-DR molecules revealed that cells transfected only with HLA-DR and not the invariant chain or HLA-DM, accumulate class II molecules mostly in the Golgi apparatus, proximal to the cell nucleus. In contrast, in cells transfected with both HLA-DR and the invariant chain, or HLA-DR, the invariant chain and HLA-DM, the class II molecules are more evenly distributed in intracellular compartments. Confocal microscopy and flow cytometry revealed that in the absence of the invariant chain, a greater number of HLA-DR molecules are transported to the cell surface. Biochemical experiments and nonequilibrium pH gradient electrophoresis revealed that HLA-DR associates with surface invariant chain in the presence of HLA-DM. In cells that lack HLA-DM, no cell-surface association of HLA-DR and Ii was observed. Taken together, these results reveal two separate and distinct functions for surface and intracellular invariant chain subsets. The intracellular invariant chain "arrests" the class II molecules in the endocytic pathway. In contrast, cell-surface invariant chain associates with class II molecules at the cell surface, possibly playing a role in recycling empty class II molecules or as an accessory molecule. 相似文献
48.
49.
Men working with zirconium compounds at one site in the Northof England have been monitored since 1975 to evaluate effectson the lung of exposure (mainly<10mg/m3) over many years.Chest radiographs (in 1975, 1978, and 1982) and lung functionmeasurements (from 1975–1988) were carried out on allmen (178) known to have worked with the compounds and an estimateof cumulative exposure was computed from job title and likelyexposures in each era. No evidence was found that zirconiumexposure resulted in abnormal chest radiographs or impairedpulmonary function. Received 21 April 1995 Accepted 25 January 1996 相似文献
50.
RINA SRIVASTAVA VW TILAK S MUKHERJEE JD YADAV 《Medical Journal Armed Forces India》1996,52(4):233-235
In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control 相似文献