Fluorescent in situ hybridization in routinely processed bone marrow aspirate clot and core biopsy sections.

Fluorescent in situ hybridization (FISH) is a technique which complements conventional cytogenetic banding analysis by allowing the evaluation of cells in interphase as well as metaphase. This technique has been used to study air-dried peripheral blood and bone marrow aspirate smears. We have applied the FISH technique to study routinely processed sections of bone marrow aspirate clot and decalcified core biopsy specimens, fixed in either formalin or B5 and embedded in paraffin. We evaluated 28 specimens (8 aspirate clot and 20 core biopsy sections) for chromosome 8 copy number, studied previously by conventional cytogenetics, and found the following distribution: 15 with disomy, 11 with trisomy, and 2 with tetrasomy. Using a chromosome 8 alpha-satellite probe, we detected fluorescent hybridization signals in 18 of 28 specimens (64%); 6 of 8 (75%) aspirate clot sections, and 12 of 20 (60%) core biopsy sections. Ten of 13 (77%) B5-fixed and 8 of 15 (53%) formalin-fixed specimens had hybridizing signals. Specimen age was a significant factor; 10 of 11 (91%) specimens processed within the last 6 months showed signals, in contrast with 8 of 17 (47%) specimens older than 6 months. In the positive specimens, 200 cells were analyzed in areas where individual cells could be identified. In the disomic specimens, two signals per cell were seen in 34 to 66% of the cells. Rare cells (0-2%) with three signals were detected. In the trisomic specimens, three signals per cell were seen in 19 to 46% of the cells. In the tetrasomic specimens, four signals per cell were seen in 15 to 25% of the cells. We conclude that the FISH technique may be useful in the detection of numerical chromosomal abnormalities such as trisomy and tetrasomy 8 in routinely processed bone marrow aspirate clot and decalcified core biopsy sections.     

Malignant schwannoma with melanocytic and neuroepithelial differentiation in an infant with congenital giant melanocytic nevus: A complex neurocristopathy

We describe an infant girl, born with a pigmented giant nevus, who developed a malignant schwannoma in the retroperitoneum at 16 months of age. At birth the nevus covered over 50% of her body and histologically was a compound nevus with extension into the deep dermis surrounding dermal appendages. The malignant schwannoma was biphasic with areas composed of spindle and round cells. Ultrastructurally, the majority of the tumor cells exhibited a Schwann cell phenotype, but neuroepithelial and melanocytic cells were identified as well. We believe that this constellation of findings represents a form of neurocristopathy. Neurocristopathy, as defined by Bolande (Hum Pathol 5:409–429, 1974), is a disease that results from aberrations in the migration, growth, or cytodifferentiation of neural crest tissues. These diseases may be simple (a singular pathologic process, usually localized) or complex (multiple neuroectodermal lesions). We report this case because the occurrence of retroperitoneal malignant schwannoma arising in a 16-month-old infant born with a pigmented giant nevus is unique, and may represent a previously undescribed form of a complex neurocristopathy.     

Plasma phenylalanine concentrations are associated with hepatic iron content in a murine model for phenylketonuria

Individuals with phenylketonuria (PKU) have been reported to have altered trace mineral status. In this study, we evaluated in a murine PKU model whether protein level and level of phenylalanine (PHE) restriction could modulate iron, copper, and zinc status. Fifty-four male weanling PKU and control mice were assigned to receive for 56 days an elemental low or normal protein diet; PKU mice also were assigned to receive PHE restriction (treated) or no restriction (untreated). PHE-restricted mice consumed a prescribed dietary PHE to maintain plasma PHE concentrations between 120 and 480 micromol/L. PHE-unrestricted and control mice received equal amounts of dietary PHE. Intestinal and hepatic copper, iron, and zinc were measured at day 56 and fecal minerals measured at baseline and day 56. Mean plasma PHE concentrations were significantly greater in PKU PHE-unrestricted versus PKU PHE-restricted mice and control mice. Mean intestinal weights when normalized for body weight were significantly greater in PKU mice versus control mice. PKU PHE-unrestricted mice had significantly lower hepatic copper and zinc than PKU PHE-restricted mice, and significantly greater hepatic iron than control and PKU PHE-restricted mice. PKU PHE-unrestricted mice on a low protein diet had hepatic iron concentrations about 1.5 times that of the other mice. Fecal iron concentrations in all mice were significantly greater at day 56 than at baseline. No animal group effects or protein level effects were found for fecal copper, iron, or zinc contents. We conclude that hyperphenylalaninemia alters the metabolism of iron, copper, and zinc in PKU mice.     

Apoptotic rate in peripheral T-cell lymphomas. A study using a tissue microarray with validation on full tissue sections

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of non-Hodgkin lymphomas with a wide spectrum of clinicopathologic features, and apoptosis mechanisms may have a role in lymphomagenesis. We assessed apoptotic rate (AR) in 112 PTCLs using a tissue microarray developed in our laboratory and a modified terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. The mean AR was 1.47% +/- 1.38% for the entire group of PTCLs (range, 0.06%-5.15%), and AR varied significantly among different tumor types. In mycosis fungoides, the mean AR was 0.74%; angioimmunoblastic T-cell lymphoma, 1.02%; PTCL, not otherwise specified, 1.38%; cutaneous anaplastic large cell lymphoma (ALCL), 1.41%; anaplastic lymphoma kinase protein (ALK)-negative ALCL, 1.43%; extranodal natural killer/T-cell lymphoma of nasal type, 2.04%; ALK-positive ALCL, 2.95%; and enteropathy-type T-cell lymphoma, 3.06%. Mean AR was higher in PTCL with large cell vs small/medium cell morphologic features (1.66% +/- 1.1% vs 0.99% +/- 1.0%). In a subset of 33 PTCLs, the tissue microarray results comparedfavorably with those obtained in full tissue sections. We conclude that the highest ARs in PTCLs are found in enteropathy-type T-cell lymphoma and ALK-positive ALCL, and that AR can be assessed reliably by using a tissue microarray.     

A survey of different high resolution visualization modes of a volumetric object with applications

Summary In view of the variety of 3D representation techniques, a clinical study was carried out in order to evaluate their respective usefulness. It appears that a single technique cannot be claimed to be valid for all clinical situations and that a combination of representations brings more relevant information. Among the different techniques a clear delineation must be established between those which allow the accurate definition of landmarks (multiplanar reformation, surface representation), and those which do not (integral shading, reconstructed radiology). The main point is the possibility to recognize anatomical landmarks on these latter modes and to choose oblique cut planes in relation to them. Visualization quality is strongly dependent upon the acquisition protocol which must provide a spatial resolution as isotropic as possible.

---

Une revue de différents modes de visualisation en haute résolution d'un objet volumique avec des applications

Résumé Face à la variété des techniques de représentation 3D une étude clinique a été conduite pour évaluer leurs utilités respectives. Il apparait qu'une technique unique ne peut pas convenir à toutes les situations cliniques et qu'une combinaison de différents modes de présentation apporte une information plus pertinente. Parmi les différentes techniques une distinction claire doit être établie entre celles qui autorisent la prise de repères précis (reformatage multiplanaire, représentation de surface), et celles qui ne le permettent pas (ombrage intégral, radiologie reconstruite). Le point principal est la possibilité de reconnaître des repères anatomiques sur ces derniers modes et de choisir des plans de coupe en relation avec eux. La qualité de la visualisation dépend étroitement du protocole d'acquisition qui doit fournir une résolution aussi isotrope que possible.

     

Inverse association between skin response to aeroallergens and Schistosoma mansoni infection

BACKGROUND: Helminthic infections and allergic disease are highly prevalent in many areas of the world. It is known that IgE antibodies are involved in the pathogenesis of both helminthiasis and atopy. However, the consequences of the presence of helminthic infections in atopic patients are still not completely understood. METHODS: Subjects infected by Schistosoma mansoni with more than 200 eggs/g of feces (n = 42) and uninfected subjects (n = 133) were selected from an endemic area of schistosomiasis. The history of allergy and results of the immediate hypersensitivity prick tests with inhalant allergen extracts were registered. Total IgE and IgE specific to S. mansoni and aeroallergens were measured in serum by ELISA. RESULTS: The proportion of individuals with a positive skin test to allergens was higher in the uninfected group (24.3%) than in the group with more than 200 eggs/g of feces (4.8%). The odds of atopy (defined as a positive test for at least one of the antigens) were 5 times higher (odds ratio = 7.0; 95% confidence interval = 1.6-31.1%; p = 0.01) in the uninfected group, after taking into account the potential influence of gender and age. While there was a tendency for higher total and S. mansoni-specific IgE levels in infected patients, an opposite trend, that is higher aeroallergen-specific IgE, was observed in uninfected subjects. CONCLUSIONS: There was a strong and statistically significant inverse association between the immediate skin test response to common aeroallergens and infection by S. mansoni. The results indicate that immediate hypersensitivity reactions may be suppressed in S. mansoni-infected individuals.     

Functional consequences of ROMK mutants linked to antenatal Bartter's syndrome and implications for treatment

The antenatal variant of Bartter's syndrome is an autosomal recessive kidney disease characterized by polyhydramnios, premature delivery, hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous, having been linked recently to mutations in an ATP- sensitive, renal outer medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl co-transporter, NKCC2. We characterized four of the mutations reported in three heterozygous ROMK variants of antenatal Bartter's and found that each expressed a distinct phenotype in Sf9 cells. One mutation expressed normal function and appears to be an allelic polymorphism. The other three mutations produced channels with significantly reduced K+fluxes. However, the mechanisms in each case were different and reflected abnormalities in phosphorylation, proteolytic processing or protein trafficking. The different mechanisms may be important in the design of appropriate therapy for patients with this disease.      

Oncornaviruses produced by murine leukemia cells in culture.

Leukemia cells from mice of the AKR and C58 strains produced leukemia viruses (MuLV) in culture that failed to induce syncytia in the XC plaque assay (XC^?), were poorly infectious for mouse embryo fibroblasts, and yielded low levels of infectious progeny upon the establishment of infection. In host range analysis the majority of these viruses were N-ecotropic, although one leukemia cell line also produced xenotropic MuLV. Viral isolates from five different leukemia cell lines were oncogenic upon inoculation into newborn AKR mice. In contrast, viruses that occurred in high titer in the tissues and sera of normal AKR mice were not oncogenic in vivo and in culture they efficiently induced (with N-ecotropism) syncytia in the XC plaque assay (XC⁺). These findings demonstrate that the transforming agent for spontaneous leukemogenesis differs in biological properties from the endogenous MuLV that is commonly observed in mice of high leukemic strains.