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111.
Loo LW Grove DI Williams EM Neal CL Cousens LA Schubert EL Holcomb IN Massa HF Glogovac J Li CI Malone KE Daling JR Delrow JJ Trask BJ Hsu L Porter PL 《Cancer research》2004,64(23):8541-8549
In this study, we performed high-resolution array comparative genomic hybridization with an array of 4153 bacterial artificial chromosome clones to assess copy number changes in 44 archival breast cancers. The tumors were flow sorted to exclude non-tumor DNA and increase our ability to detect gene copy number changes. In these tumors, losses were more frequent than gains, and gains in 1q and loss in 16q were the most frequent alterations. We compared gene copy number changes in the tumors based on histologic subtype and estrogen receptor (ER) status, i.e., ER-negative infiltrating ductal carcinoma, ER-positive infiltrating ductal carcinoma, and ER-positive infiltrating lobular carcinoma. We observed a consistent association between loss in regions of 5q and ER-negative infiltrating ductal carcinoma, as well as more frequent loss in 4p16, 8p23, 8p21, 10q25, and 17p11.2 in ER-negative infiltrating ductal carcinoma compared with ER-positive infiltrating ductal carcinoma (adjusted P values < or = 0.05). We also observed high-level amplifications in ER-negative infiltrating ductal carcinoma in regions of 8q24 and 17q12 encompassing the c-myc and c-erbB-2 genes and apparent homozygous deletions in 3p21, 5q33, 8p23, 8p21, 9q34, 16q24, and 19q13. ER-positive infiltrating ductal carcinoma showed a higher frequency of gain in 16p13 and loss in 16q21 than ER-negative infiltrating ductal carcinoma. Correlation analysis highlighted regions of change commonly seen together in ER-negative infiltrating ductal carcinoma. ER-positive infiltrating lobular carcinoma differed from ER-positive infiltrating ductal carcinoma in the frequency of gain in 1q and loss in 11q and showed high-level amplifications in 1q32, 8p23, 11q13, and 11q14. These results indicate that array comparative genomic hybridization can identify significant differences in the genomic alterations between subtypes of breast cancer. 相似文献
112.
Toxic proteins released from mitochondria in cell death 总被引:29,自引:0,他引:29
Saelens X Festjens N Vande Walle L van Gurp M van Loo G Vandenabeele P 《Oncogene》2004,23(16):2861-2874
A plethora of apoptotic stimuli converge on the mitochondria and affect their membrane integrity. As a consequence, multiple death-promoting factors residing in the mitochondrial intermembrane space are liberated in the cytosol. Pro- and antiapoptotic Bcl-2 family proteins control the release of these mitochondrial proteins by inducing or preventing permeabilization of the outer mitochondrial membrane. Once released into the cytosol, these mitochondrial proteins activate both caspase-dependent and -independent cell death pathways. Cytochrome c was the first protein shown to be released from the mitochondria into the cytosol, where it induces apoptosome formation. Other released mitochondrial proteins include apoptosis-inducing factor (AIF) and endonuclease G, both of which contribute to apoptotic nuclear DNA damage in a caspase-independent way. Other examples are Smac/DIABLO (second mitochondria-derived activator of caspase/direct IAP-binding protein with low PI) and the serine protease HtrA2/OMI (high-temperature requirement protein A2), which both promote caspase activation and instigate caspase-independent cytotoxicity. The precise mode of action and importance of cytochrome c in apoptosis in mammalian cells has become clear through biochemical, structural and genetic studies. More recently identified factors, for example HtrA2/OMI and Smac/DIABLO, are still being studied intensively in order to delineate their functions in apoptosis. A better understanding of these functions may help to develop new strategies to treat cancer. 相似文献
113.
Loo VS Diaz T Gadelha AM Campos DP Pilloto JH Brandao PS Grinsztejin B Veloso dos Santos VG 《AIDS care》2004,16(7):834-840
The objective of the paper was to compare provider practices in prescribing antiretroviral (ARV) drug regimens and use of laboratory monitoring at three health care facilities and to determine whether Brazilian national guidelines are being followed. A retrospective, cross-sectional survey was employed. We selected a sequential sample of patients on ARV therapy who registered at three health care facilities in Rio de Janeiro, Brazil, during 2001. We abstracted 2001 patient visit data from medical records using standardized data forms. Provider practice was compared to the 2000 Brazil national guidelines for ARV use. Providers who prescribed recommended or acceptable regimens were considered as having conformed to guidelines. Only 2% of patient records (N=984) reported use of inappropriate regimens as defined by the Brazil 2000 national ARV guidelines. Forty-nine per cent of patients at the Evandro Chagas hospital, 17% of those at Hospital Geral, and 57% of those at Centro da Saude were prescribed recommended therapies. Twenty per cent of patients seen at the public district hospital received dual ARV therapy, an acceptable regimen at the time. Although the national guidelines do not provide recommendations on laboratory monitoring, during the 1 year study period a majority of patients had at least one CD4+ cell count (92%) or viral load measurement (86%). Providers' practices in prescribing ARV regimens at these Rio de Janeiro facilities conform to national guidelines. Physicians would benefit from Brazilian ARV guidelines which incorporate the international consensus on the frequency of laboratory monitoring appropriate for patients in resource-constrained settings. 相似文献
114.
115.
Loo SK Fisher SE Francks C Ogdie MN MacPhie IL Yang M McCracken JT McGough JJ Nelson SF Monaco AP Smalley SL 《Molecular psychiatry》2004,9(5):485-493
Attention-deficit/hyperactivity disorder (ADHD) and reading disability (RD) are common highly heritable disorders of childhood, which frequently co-occur. Data from twin and family studies suggest that this overlap is, in part, due to shared genetic underpinnings. Here, we report the first genome-wide linkage analysis of measures of reading ability in children with ADHD, using a sample of 233 affected sibling pairs who previously participated in a genome-wide scan for susceptibility loci in ADHD. Quantitative trait locus (QTL) analysis of a composite reading factor defined from three highly correlated reading measures identified suggestive linkage (multipoint maximum lod score, MLS>2.2) in four chromosomal regions. Two regions (16p, 17q) overlap those implicated by our previous genome-wide scan for ADHD in the same sample: one region (2p) provides replication for an RD susceptibility locus, and one region (10q) falls approximately 35 cM from a modestly highlighted region in an independent genome-wide scan of siblings with ADHD. Investigation of an individual reading measure of Reading Recognition supported linkage to putative RD susceptibility regions on chromosome 8p (MLS=2.4) and 15q (MLS=1.38). Thus, the data support the existence of genetic factors that have pleiotropic effects on ADHD and reading ability--as suggested by shared linkages on 16p, 17q and possibly 10q--but also those that appear to be unique to reading--as indicated by linkages on 2p, 8p and 15q that coincide with those previously found in studies of RD. Our study also suggests that reading measures may represent useful phenotypes in ADHD research. The eventual identification of genes underlying these unique and shared linkages may increase our understanding of ADHD, RD and the relationship between the two. 相似文献
116.
Fleck MP Chaves ML Poirier-Littré MF Bourdel MC Loo H Guelfi JD 《The Journal of nervous and mental disease》2004,192(2):103-110
Among various research strategies for depression, the cross-cultural approach is a useful tool to investigate depressive disorders. The Hamilton Rating Scale for Depression was applied to 130 depressed inpatients in France and Brazil. Items were factorized by principal component analysis with Varimax rotation using the Kaiser or simulation method for factor sorting. Three factors were obtained in France, and four in Brazil. The first factor includes the core symptoms of depression in both samples. Qualitative and quantitative differences appeared in the anxiety factor between Brazilian and French samples. Insomnia items appeared as another factor for both groups. A limitation of this study is that it was conducted with small inpatient samples. Principal component analysis of the Hamilton Rating Scale for Depression for depressive inpatients in these two countries showed a similar structure. Differences observed were in the way anxiety items were distributed. 相似文献
117.
BACKGROUND: Alveolar rhabdomyosarcoma (RMS) has a high risk for local and distal failure. Multimodal management of a patient with alveolar RMS of the cervix uteri is outlined. CASE: A 39-year-old woman suffered from alveolar RMS of the cervix without involvement of uterus and parametrium. She was treated with total hysterectomy and left salpingo-oophorectomy. Systemic chemotherapy and pelvic irradiation were also offered. She remains in clinical remission 3 years after presentation. CONCLUSION: Postoperative chemotherapy and irradiation could be effective treatments for alveolar rhabdomyosarcoma of the cervix in adult patients. 相似文献
118.
119.
Ladas JG Yu F Loo R Davis JL Coleman AL Levinson RD Holland GN 《Investigative ophthalmology & visual science》2001,42(11):2584-2588
PURPOSE: To determine whether there is a relationship between the aqueous humor protein level and outflow facility in patients with uveitis. METHODS: Aqueous humor protein levels were determined by laser flare photometry, and outflow facility was determined by Schiotz tonography. RESULTS: Thirty patients with uveitis and 10 control subjects were studied. Outflow facility was lower in patients with uveitis (0.21 +/- 0.12 microl/min x mm Hg) than in control subjects (0.33 +/- 0.05 microl/min x mm Hg, P < 0.001). Patients with uveitis and laser flare photometry results (flare) more than 20 photon units/msec (n = 21) had a lower outflow facility (0.17 +/- 0.07 microl/min x mm Hg) than patients with uveitis and flare less than 20 photon units/msec (n = 9, 0.32 +/- 0.14 microl/min x mm Hg, P = 0.004). Furthermore, no difference was identified between outflow facility in patients with active uveitis (those who had anterior chamber cells) and flare less than 20 photon units/msec and outflow in control subjects. In patients with uveitis, there was a linear correlation between flare and outflow facility (r = -0.50, P = 0.005). There was no relationship between flare measurements and either intraocular pressure or aqueous humor cell levels when scored with a clinical, semiquantitative system. CONCLUSIONS: Outflow facility is significantly reduced in patients with uveitis who have high aqueous humor protein levels. Outflow facility appears to be normal in patients with active uveitis whose flare levels are low, and therefore the association between flare and outflow facility does not appear to be an indirect reflection of elevated anterior chamber cells. It is possible that elevated aqueous humor protein levels contribute to the development of uveitic glaucoma in some individuals by decreasing aqueous humor outflow facility, although a causal relationship cannot be established on the basis of this study. 相似文献
120.
The effects of dietary supplementation with either sucrose or starch (50 g/kg regular food for 2 weeks) on central 5-hydroxytryptamine (5HT; serotonin) release were investigated in freely-moving rats. It has been suggested that the amount of transmitter that serotoninergic neurons release might be altered by food intake. We monitored the effects of sucrose and starch on concentrations of extracellular 5HT, its metabolite 5-hydroxyindoleacetic acid (5HIAA), gamma-aminobutyric acid (GABA) and dopamine in the hippocampus, using in vivo microdialysis. The major finding was that baseline levels of extracellular hippocampal 5HT in rats with ad libitum access to food supplemented with sucrose were significantly higher compared with the starch control group. We then verified that sucrose supplementation affected the potency of S(+)fenfluramine to increase hippocampal 5HT levels. In both groups of rats, acute intraperitoneal injection (1 mg/kg) of this anorectic drug induced a response curve of the extracellular hippocampal 5HT levels, with a shape that corresponded with earlier data for different brain areas often using up to 10-fold higher doses of S(+)fenfluramine. Nevertheless, we showed that throughout the experiment the absolute values of the sucrose response curve remained higher than in the starch group. On the other hand, S(+)fenfluramine exerted longer lasting effects in the starch group, as compared with the sucrose group. Significant decreases in levels of extracellular hippocampal 5HIAA levels following S(+)fenfluramine administration were simultaneously observed. A practical implication of the present findings is that dietary sucrose may bias the results of studies investigating brain serotoninergic mechanisms and the effects of (anorectic) drugs interacting with 5HT systems in the hippocampus. 相似文献