Computer-mediated measurement and subjective ratings of white matter hyperintensities in vascular dementia: relationships to neuropsychological performance

White matter hyperintensities (WMHs) are frequently found on MRI studies of vascular dementia (VaD) patients. As several studies have demonstrated that WMHs are often associated with severity of illness, cognitive impairment, and functional decline, the accurate and reliable measurement of WMHs on MRI is an important, yet often overlooked, prerequisite for accurate interpretation of neuroimaging studies. Using a sample of 39 VaD patients, we evaluated the reliability and validity of a visual ordinal rating scale and a computer-mediated thresholding technique to evaluate WMHs. Results indicated the computer-mediated technique had slightly stronger inter-rater reliability than the visual ordinal rating scale. Furthermore, the computer-mediated thresholding technique was correlated with measures of neuropsychological functioning believed to be compromised in VaD (i.e., psychomotor speed, executive functioning) while the visual rating scale was not. Results suggest that this computer-mediated thresholding technique is superior to visual ratings of WMHs.     

Feasibility of Respiratory Triggering for MR-Guided Microwave Ablation of Liver Tumors Under General Anesthesia

We obtained clear and reproducible MR fluoroscopic images and temperature maps for MR image-guided microwave ablation of liver tumors under general anesthesia without suspending the artificial ventilation. Respiratory information was directly obtained from air-way pressure without a sensor on the chest wall. The trigger signal started scanning of one whole image with a spoiled gradient echo sequence. The delay time before the start of scanning was adjusted to acquire the data corresponding to the k-space center at the maximal expiratory phase. The triggered images were apparently clearer than the nontriggered ones and the location of the liver was consistent, which made targeting of the tumor easy. MR temperature images, which were highly susceptible to the movement of the liver, during microwave ablation using a proton resonance frequency method, could be obtained without suspending the artificial ventilation. Respiratory triggering technique was found to be useful for MR fluoroscopic images and MR temperature monitoring in MR-guided microwave ablation of liver tumors under general anesthesia.     

Weight loss in adults with Down syndrome and with dementia in Alzheimer's disease

An association between weight loss and Alzheimer's disease has been established in the general population but little information is available regarding this association in people with intellectual disabilities. A 4-year longitudinal study of adults with Down syndrome with and without Alzheimer's disease was undertaken. Age-associated weight loss was seen in virtually all older adults with Down syndrome. A significant association between weight loss and Alzheimer's disease was found for older adults with Down syndrome. This study highlights important research and clinical issues regarding weight loss and nutrition in Down syndrome adults with dementia.     

Ocular pathology in acquired immunodeficiency syndrome

Gross and microscopic ocular findings were prospectively studied in 38 human immunodeficiency virus (HIV)-seropositive subjects undergoing postmortem examination. Pathologic lesions were detected in 27 patients (71%), with 67% of the abnormal findings detected only microscopically. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article.     

Racial and ethnic differences in survival of children with acute lymphoblastic leukemia

Black children with acute lymphoblastic leukemia (ALL) have poor outcomes, but limited information is available for children from other racial and ethnic backgrounds, such as Hispanic and Asian. We undertook a retrospective cohort study of children with ALL treated on Children's Cancer Group therapeutic protocols to determine outcomes by racial and ethnic backgrounds of patients treated with contemporary risk-based therapy. In total, 8447 children (white, n = 6703; Hispanic, n = 1071; black, n = 506; and Asian, n = 167) with newly diagnosed ALL between 1983 and 1995 were observed for a median of 6.5 years. Analysis of disease outcome was measured as overall survival (OS) and event-free survival (EFS) and was adjusted for known predictors of outcome including clinical features, disease biology, socioeconomic status, and treatment era (1983-1989 vs 1989-1995). There was a statistically significant difference in survival by ethnicity (P <.001). Five-year EFS rates were: Asian, 75.1% +/- 3.5%; white, 72.8% +/- 0.6%; Hispanic, 65.9% +/- 1.5%; and black, 61.5% +/- 2.2%. Multivariate analysis revealed that when compared with white children, black and Hispanic children had worse outcomes and Asian children had better outcomes after adjusting for known risk factors. The poorer outcomes among black children were most apparent among patients with standard-risk features (relative risk [RR], 2.0; 95% confidence interval [CI], 1.6-2.5), whereas poorer outcomes in Hispanic children (RR, 1.4; 95% CI, 1.2-1.6) were most evident among patients with high-risk features. Asian children had better outcomes than all racial and ethnic groups among high-risk patients, particularly in the recent era (5-year EFS, 90.9% +/- 6.1%). Racial and ethnic differences in OS and EFS persist among children with ALL who receive contemporary risk-based therapy. Future studies should focus on reasons-perhaps compliance or pharmacogenetics-for those differences.     

Abnormalities of chromosome bands 15q13-15 in childhood acute lymphoblastic leukemia

BACKGROUND: Recurring breakpoints in chromosome bands 15q13-15 occur infrequently in leukemia. To the authors' knowledge, the clinical significance of these breakpoints in childhood acute lymphoblastic leukemia (ALL) has not been previously investigated. METHODS: Centrally reviewed karyotypes of children with newly diagnosed ALL enrolled on Children's Cancer Group protocols from 1988 to 1995 formed the basis of the current report. Statistical analyses used chi-square tests for homogeneity of proportions, and outcome was analyzed using life table methods and associated statistics. RESULTS: Of 1946 cases with centrally reviewed and accepted cytogenetic analyses, 23 cases (1%) had breakpoints in chromosome bands 15q13-15. Most patients with 15q13-15 breakpoints had standard risk ALL, although breakpoints in 15q13-15 occurred more frequently in infants than in older children. The majority of these patients (16 patients; 70%) had balanced 15q13-15 rearrangements. Additional chromosomal abnormalities not involving 15q included abnormal 12p, abnormal 9p, Philadelphia chromosome, deletion 6q, and an 11q23 breakpoint. Thirteen (57%) 15q13-15 breakpoints occurred in pseudodiploid karyotypes; five (22%) were in hyperdiploid karyotypes with 47-50 chromosomes; two (9%) were in hyperdiploid karyotypes with > 50 chromosomes; and three (13%) were in hypodiploid karyotypes. Of the 23 patients with 15q13-15 breakpoints, 21 were survivors, 18 survived event-free for 2.2-9.3 years, and 3 were alive 1 to 3 years after a relapse at time of writing. CONCLUSIONS: The current study suggests that genes at 15q13-15 may be involved in the leukemogenesis of some cases of childhood ALL, but that with current intensive therapy such aberrations do not confer increased risk of treatment failure.     

IL-13R(alpha)2, a decoy receptor for IL-13 acts as an inhibitor of IL-4-dependent signal transduction in glioblastoma cells

Interleukin (IL)-4 and IL-13 share the type II IL-4 receptor for cell signaling. We show that despite expressing the necessary signaling components, glioblastoma cells failed to respond to either IL-4 or IL-13. This was in part because of the expression of a high-affinity IL-13-binding transmembrane protein IL-13R(alpha)2 that inhibited IL-13-mediated Stat6 activation by acting as a decoy receptor. In contrast, normal human astrocytes that did not express the IL-13R(alpha)2 gene efficiently induced Stat6 activation in response to both IL-4 and IL-13. Transient expression of the IL-13R(alpha)2 transgene in nonexpressing heterologous cells inhibited not only IL-13- but also IL-4-mediated signal transduction and Stat6-responsive gene expression. The inhibition was likely mediated through the physical interaction between the short intracellular domain of the IL-13R(alpha)2 protein and the cytoplasmic domain of the IL-4R(alpha) chain that harbors the Stat6 docking sites. Thus, IL-13R(alpha)2 acts as an inhibitor of IL-4-dependent signal transduction pathways via a novel mechanism that is independent of ligand binding.     

Effect of endosulfan on antioxidants of freshwater fish Channa punctatus Bloch: 1. Protection against lipid peroxidation in liver by copper preexposure

Effect of a single exposure of endosulfan (5 ppb) on catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), and reduced glutathione (GSH) of liver, kidney, and gill of a freshwater fish (Channa punctatus Bloch) were evaluated after 24 h of treatment. Endosulfan exposure resulted in a significant induction (p < 0.05–0.001) of GPx, GST activity, and GSH levels in all the organs. However, CAT activity was found to be significantly decreased (p < 0.01–0.001). Lipid peroxidation (LPO) values were also determined in liver, kidney, and gill and a significant increase in LPO values (p < 0.05–0.01) was observed in all the organs. We also investigated whether preexposure to low concentration of copper (10 ppb) for 4 weeks has any protective effect against endosulfan-induced oxidative damage. In copper-acclimatized endosulfan-exposed fish, a significant decrease in GPx (p < 0.001), GST (p < 0.05), GSH (p < 0.001) levels, and LPO (p < 0.01) was observed in the liver, whereas CAT activity was increased significantly (p < 0.001). However, kidney and gill did not show any significant alterations in antioxidant levels. The results of this study demonstrate that endosulfan induces peroxidative damage in liver, kidney, and gill in response to which levels of antioxidant were modulated. However, when fish preacclimatized to copper were exposed to endosulfan, protection against oxidative damage was observed only in the liver. It is proposed that measurement of antioxidants in fish tissues may prove to be useful in biomonitoring of exposure to aquatic pollutants. Received: 28 November 2000/Accepted: 14 April 2001