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1.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
5.
Effects of a brisk walk on lipoprotein lipase activity and plasma triglyceride concentrations in the fasted and postprandial states 总被引:3,自引:0,他引:3
This study aimed to determine whether changes in plasma heparin-releasable lipoprotein lipase (LPL) activity following a brisk
walk were associated with decreases in fasting and/or postprandial triglyceride (TG) concentrations. Two groups of pre-menopausal
women participated. In one group (fasting study group, n=10), TG concentrations and post-heparin plasma LPL activity were measured in the fasted state on two occasions: ~18 h after
a 2-h treadmill walk at 50% maximal oxygen uptake (exercise trial); and after a day of no exercise (control trial). The other
group (postprandial study group, n=9) undertook two oral fat tolerance tests (blood samples taken fasting and for 6 h after a high-fat meal), with plasma LPL
activity measured 6 h after meal ingestion. Pre-conditions were the same as for the fasting study group (i.e. control and
prior exercise). Prior exercise reduced fasting TG concentrations by 23 (7)% (fasting study group) [mean (SEM)] and by 18
(9)% (postprandial study group) (both P<0.05), and the postprandial TG response by 23 (6)% (postprandial study group) (P<0.01). Plasma LPL activity was not significantly increased by exercise in either the fasting or postprandial study groups.
However, exercise-induced changes in both fasting and postprandial LPL activity were significantly correlated with the respective
exercise-induced changes in fasting TG concentration and the postprandial TG response (r=−0.70 and −0.77 respectively, P<0.05 for both). These data suggest that increased LPL activity may contribute to the hypotriglyceridaemic effect of moderate
exercise, although other mechanisms are also likely to be involved.
Electronic Publication 相似文献
6.
Hart TC; Bowden DW; Bolyard J; Kula K; Hall K; Wright JT 《Human molecular genetics》1997,6(13):2279-2284
Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a
highly penetrant autosomal dominant trait that is characterized by variable
clinical expression. The principal clinical features include kinky/curly
hair in infancy, enamel hypoplasia, taurodontism, as well as increased
thickness and density of cranial bones. Possible genetic linkage has been
reported for TDO with the ABO blood group locus, but the gene defect
remains unknown. We have identified four multiplex families (n = 63, 39
affected, 24 unaffected) from North Carolina segregating TDO. We previously
have excluded a major locus for TDO in the ABO region for these families.
Utilizing a genome-wide search strategy, we obtained conclusive evidence
for linkage of the TDO syndrome locus to markers on chromosome 17q21
(D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic
heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7
cM chromosomal segment flanked by D17S932 and D17S941. This finding
represents the first step towards isolation and cloning of the TDO gene.
Identification of this gene has important implications for understanding
normal and abnormal craniofacial development of hair, teeth and bone.
相似文献
7.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
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The importance of the extracellular matrix (ECM) in epithelial-mesenchymal interactions in developing organisms is well established. Proteoglycans and interstitial collagens are required for the growth, morphogenesis, and differentiation of epithelial organs and the distribution of these molecules has been described. However, much less is known about other ECM macromolecules in developing epithelial organs. We used confocal microscopy to examine the distribution of laminin, heparan sulfate (BM-1) proteoglycan, fibronectin, and collagen types I, IV, and V, in mouse embryonic salivary glands. Organ rudiments were isolated from gestational day 13 mouse embryos and cultured for 24, 48, or 72 hours. Whole mounts were stained by indirect immunofluorescence and then examined using a Zeiss Laser Scan Microscope. We found that each ECM component examined had a distinct distribution and that the distribution of some molecules varied with culture time. Laminin was mainly restricted to the basement membrane. BM-1 proteoglycan was concentrated in the basement membrane and also formed a fine network throughout the mesenchyme. Type IV collagen was mainly located in the basement membrane of the epithelium, but it was also present throughout the mesenchyme. Type V collagen was distributed throughout the mesenchyme at 24 hours, but at 48 hours was principally located in the basement membrane. Type I collagen was distributed throughout the mesenchyme at all culture times, and accumulated in the clefts and particularly at the epithelial-mesenchymal interface as time in culture increased. Fibronectin was observed throughout the mesenchyme at all times. 相似文献
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