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D Alter

Publications and source records attributed to D Alter.

7 recordsLinked to original sources
PubMed2000

Cytogenetic study of a patient with infant acute lymphoblastic leukemia using GTG-banding and chromosome painting.

Numerical and structural chromosomal abnormalities occur in up to 90% of cases of childhood acute lymphoblastic leukemia (ALL). Two-thirds of these abnormalities are recurrent. The most common abnormalities are pseudodiploidy and t(1;19), occurring 40 and 5-6% of the time. Hyperdiploidy has the best prognosis, with an 80-90% 5-year survival. The 4;11 translocation has the worst prognosis, with a 10-35% 5-year survival. We report a patient with infant acute lymphoblastic leukemia and nonrecurrent rearrangements of chromosomes 10 and 11. Structural rearrangements between chromosomes 10 and 11 have been observed in 0.5% of all cases of childhood ALL with cytogenetic abnormalities. The identification of the apparently unique structural abnormalities was achieved using fluorescent in situ hybridization (FISH) with chromosome 10- and chromosome 11-specific painting probes as an adjunct to conventional cytogenetics. As is often the case, suboptimal preparations often preclude unequivocal identification of complex rearrangements by conventional banding techniques. The cytogenetic diagnosis of our patient was established as 46,XY, der(10)-t(10;11)(p15;q14)t(10;11)(q25;p11), der(11)t(10;11)(p15;q14)t(10;11)-(q25;p11). The benefits of FISH serve to increase the resolution of detection for chromosomal abnormalities and the understanding of the pathogenic mechanisms of childhood ALL.

Child↗
PubMed1997

Test performance in systemic sclerosis: anti-centromere and anti-Scl-70 antibodies.

PURPOSE: To determine the sensitivity and specificity of anti-centromere (ACA) and anti-Scl-70 antibodies in systemic sclerosis (SSc). METHODS: Four-hundred ninety-seven English language articles published from 1966 to 1994 were identified by structured MEDLINE search. Articles in which either ACA or anti-Scl-70 antibodies were measured in both SSc patients and a non-SSc control group were reviewed and rated using a previously published diagnostic testing scale. Reported sensitivity and specificity from each study was converted into a 2 x 2 table, and combined across studies to calculate summary rates for each antibody. Author's clinical classification criteria for SSc served as the gold standard for disease diagnosis. RESULTS: In 30 articles that fulfilled inclusion criteria, ACA were found in 441 of 1,379 SSc patients (sensitivity 32%, range 17% to 56%). This increased to 57% (332 of 585) in patients with the limited cutaneous, or CREST, subset of SSc (IcSSc). Anti-Scl-70 antibodies were found in 366 of 1,074 SSc patients (sensitivity 34%, range 3% to 75%), and this increased slightly to 40% in patients with the diffuse cutaneous form of SSc (dcSSc). Both antibodies were measured in 670 patients, and either test was positive in 58% (range 29% to 86%), but in only 3 patients were both antibodies present. The specificity of each antibody was high, but varied by control group. ACA were present in 5% and anti-Scl-70 antibodies were present in 2% of patients with other connective tissue diseases, but fewer than 1% of disease free controls had either antibody present. CONCLUSIONS: As individual diagnostic tests in SSc, both ACA and anti-Scl-70 antibodies are highly specific. Each performs somewhat better as discriminators of clinical subsets for patients in whom a diagnosis of SSc has already been established. Clinicians can rely on a positive test result as being specific in the detection of disease, but 40% of SSc patients are likely to have neither antibody present, and a negative result does not exclude the diagnosis. Measurement of these antibodies should be considered secondary to the clinical features when making a diagnosis of SSc.

Antibodies, Antinuclear↗
PubMed1994

Comparison of the Howmedica and Synthes military external fixation frames.

To direct the U.S. military purchase of deployable external fixation gear, a project was designed to compare the biomechanical properties and ease of clinical application of military external fixators developed by Synthes and Howmedica. The project assessed (a) ease of application, (b) biomechanics, (c) heat stability, and (d) product line compatibility. Pretrained general surgery residents were provided with fresh cadaver limbs with simulated grade IIIB tibial fractures and 5-cm middiaphyseal defects. All chose the Howmedica Ultra-X for its ease of application but, on manual testing, noted that the Synthes Trauma-Fix was more stable. The frames were biomechanically tested in a previously validated model with strictly controlled parameters. The Howmedica Ultra-X demonstrated only 75% of the compressive stiffness, 29% of the anteroposterior bending stiffness, and 51% of the torsional stiffness of the Synthes Trauma-Fix. The Ultra-X failed to withstand steam sterilization and was significantly weaker than, and incompatible with, Howmedica's commercially available product. The Trauma-Fix demonstrated no statistically significant difference from Synthes' commercially available product. The Howmedica Ultra-X is unsuitable for military external fixation: The biomechanical properties are not equivalent to those of the unilateral Hoffmann frame, it is incompatible with commercially available Howmedica external fixators, and it fails to withstand heat sterilization.

Biomechanical Phenomena↗