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Altered matrix degradation may be playing a role in the development of initial mesangial expansion and subsequent glomerulosclerosis in persons with heroin abuse. We studied whether morphine, a metabolite of heroin, had any effect on lysosomal content of cathepsin B and L in mesangial cells. Morphine (10–6 M) increased (P<0.01) mesangial cathepsin B and L activity (control, 22.1+2.2 vs. morphine, 31.4+1.4 mol NMec/g protein,N=5). Morphine (10–6 M) also increased (P<0.01) glomerular cathepsin B and L activity (control, 0.1+0.01 vs. morphine, 2.2±0.2 pmol NMec/g protein,N=3). This effect of morphine occurred in a dose-dependent manner. These results suggest that morphine enhances cathepsin B and L activity in mesangial cells and isolated glomeruli. This effect of morphine may enhance capacity of mesangial cells to degrade increased amount of mesangial macromolecules. 相似文献
53.
Susan De Santi Ph.D. Mony J. de Leon Ed.D. Antonio Convit M.D. Chaim Tarshish M.S. Henry Rusinek Ph.D. Wai Hon Tsui M.S. Elia Sinaiko Ph.D. Gene-Jack Wang M.D. Elsa Bartlet Ph.D. Nora Volkow M.D. 《The Psychiatric quarterly》1995,66(4):357-370
While many neuropsychological studies have demonstrated age-related performance alterations in tests thought to reflect frontal and temporal lobe function, there is little direct observation and comparison of these hypothesized brain changesin vivo. The cerebral glucose metabolism of frontal, temporal, and cerebellar regions was examined in 40 young (
=27.5±4.9) and 31 elderly (
=67.6 ± 8.8) normal males using PET-FDG. Univariate analysis showed age-related metabolic reductions in all frontal and temporal lobe regions. The reductions ranged from 13%–24% with the greatest changes in the frontal lobes. Multiple regression analyses showed a stronger age relationship with frontal lobe than with temporal lobe metabolism. The dorsal lateral frontal lobe was the region that appears to change most within the frontal lobes. Examination of the temporal lobe showed that age contributed equally to the metabolic variance of both the lateral temporal lobe and hippocampus. These results suggest that age-related metabolic changes exist in both frontal and temporal lobes and that the frontal lobe change is greater. 相似文献
54.
Emmanuel Le Poul Nora Laaris Edith Doucet Anne-Marie Laporte Michel Hamon Laurence Lanfumey 《Naunyn-Schmiedeberg's archives of pharmacology》1995,352(2):141-148
Electrophysiological and autoradiographic approaches were used to assess possible changes in 5-hydroxytryptamine (serotonin) 5-HT1A receptors in the rat dorsal raphe nucleus after a subchronic treatment with fluoxetine or paroxetine, two specific serotonin reuptake inhibitors with antidepressant properties. Fluoxetine or paroxetine were injected daily (5 mg/kg, i.p.) for various time periods up to 21 days. Electrophysiological recordings performed 24 h after the last injection showed that the potency of the 5HT1A receptor agonist, 8-OH-DPAT, to depress the firing of serotoninergic neurons in the dorsal raphe nucleus within brain stem slices was significantly reduced as early as after a 3-day treatment with either drug. The proportion of recorded neurons showing desensitization of somatodendritic 5-HT1A autoreceptors increased along the treatment from 40% on the 3rd day to 60–80% on the 21st day. At no time during the treatment, was the specific binding of [3H]8-OHDPAT (agonist radioligand) or [3H] WAY-100 635 (antagonist radioligand) to 5-HT1A receptors modified in the dorsal raphe nucleus or in other brain areas, suggesting that neither the density nor the coupling of these receptors to G-proteins were probably altered in rats injected with fluoxetine or paroxetine for up to 21 days.These results show that adaptive desensitization of somatodendritic 5-HT1A autoreceptors within the dorsal raphe nucleus can already be detected after a 3-day treatment with selective serotonin reuptake inhibitors. Rather than the desensitization per se, it may be the progressive increase in the number of serotoninergic neurons with desensitized 5-HT1A autoreceptors which plays a critical role in the (slowly developing) antidepressant action of these drugs. 相似文献
55.
Stephen Lutz Carol Spence Edward Chow Nora Janjan Stephen Connor 《Journal of clinical oncology》2004,22(17):3581-3586
PURPOSE: Radiation oncologists and hospice professionals both provide end-of-life care for oncology patients, and little has been written about the interface between these two groups of specialists. Hospice professionals were surveyed to assess the perceived need for palliative radiotherapy in the hospice setting, to investigate factors that limit the access of hospice patients to radiotherapy, and to suggest areas of future collaboration on education, research, and patient advocacy. PATIENTS AND METHODS: Members of the National Hospice and Palliative Care Organization (NHPCO) and American Society for Therapeutic Radiology and Oncology jointly authored a questionnaire to investigate the beliefs of hospice professionals toward the use of radiotherapy for oncology patients in hospice. The questionnaire was distributed to all NHPCO member institutions, and the results were compiled and statistically analyzed. RESULTS: Four hundred eighty of more than 1,800 surveyed facilities responded to the questionnaire. The findings suggest that the majority of hospice professionals feel that radiotherapy is important in palliative oncology and that radiotherapy is widely available in the United States. Yet less than 3% on average of hospice patients served by hospices responding to the survey actually received radiotherapy in 2002. The most common barriers to radiotherapy in hospice care include radiotherapy expense, transportation difficulties, short life expectancy, and educational deficiencies between the specialties. CONCLUSION: Multiple barriers act to limit the use of palliative radiotherapy in hospice care. Finding ways to surmount these obstacles will provide opportunity for improvement in the end-of-life care of cancer patients. 相似文献
56.
Steven J Skates Nora Horick Yinhua Yu Feng-Ji Xu Andrew Berchuck Laura J Havrilesky Henk W A de Bruijn Ate G J van der Zee Robert P Woolas Ian J Jacobs Zhen Zhang Robert C Bast 《Journal of clinical oncology》2004,22(20):4059-4066
PURPOSE: In CA-125-based ovarian cancer screening trials, overall specificity and screening sensitivity of ultrasound after an elevated CA-125 exceeded 99.6% and 70%, respectively, thereby yielding a positive predictive value (PPV) exceeding 10%. However, sensitivity for early-stage disease was only 40%. This study aims to increase preoperative sensitivity for early-stage ovarian cancer while maintaining the annual referral rate to ultrasound at 2% by combining information across CA-125II, CA 15-3, CA 72-4, and macrophage colony-stimulating factor (M-CSF). For direct comparisons between marker panels, all sensitivity results correspond to a 98% fixed first-line specificity (referral rate 2%). PATIENTS AND METHODS: Logistic regression, classification tree, and mixture discriminant analysis (MDA) models were fit to a training data set of preoperative serum measurements (63 patients, 126 healthy controls) from one center. Estimates from the training set applied to an independent validation set (60 stage I to II patients, 98 healthy controls) from two other centers provided unbiased estimates of sensitivity. RESULTS: Preoperative sensitivities for early-stage disease of the optimal panels were 45% for CA-125II; 67% for CA-125II and CA 72-4; 70% for CA-125II, CA 72-4, and M-CSF; and 68% for all four markers (latter two results using MDA). CONCLUSION: Efficiently combining information on CA-125II, CA 72-4, and M-CSF significantly increased preoperative early-stage sensitivity from 45% with CA-125II alone to 70%, while maintaining 98% first-line specificity. Screening trials with these markers using MDA followed by referral to ultrasound may maintain previously high levels of specificity and PPV, while significantly increasing early-stage screening sensitivity. MDA is a useful, biologically justified method for combining biomarkers. 相似文献
57.
Haptoglobin-alpha subunit as potential serum biomarker in ovarian cancer: identification and characterization using proteomic profiling and mass spectrometry. 总被引:24,自引:0,他引:24
Bin Ye Daniel W Cramer Steven J Skates Steven P Gygi Vanessa Pratomo Lanfei Fu Nora K Horick Larry J Licklider John O Schorge Ross S Berkowitz Samuel C Mok 《Clinical cancer research》2003,9(8):2904-2911
PURPOSE: The objective of this study was to identify and characterize new serum biomarkers in ovarian cancer patients using mass spectrometric protein profiling and specific immunological assays. Experimental Design: Serum samples from 80 cancer patients and 91 healthy women were analyzed by surface enhanced laser desorption and ionization-mass spectrometry (MS) profiling. A candidate biomarker was purified by affinity chromatography, and its sequence was determined by liquid chromatography-tandem MS. An antibody was generated from the synthesized peptide for quantitative validation in the cases and controls. CA125 was determined and compared with the same set of specimens. RESULTS: Using surface enhanced laser desorption and ionization, we found a serum biomarker at approximately 11700 Da, which had peak intensity significantly higher in cases (1.366) compared with controls (0.208, P = 0.002), and subsequently identified this as the alpha chain of haptoglobin. ELISA indicated that Hp-alpha was =2-fold higher in cancer serum compared with normal, benign tumor, and other gynecological cancers (P < 0.05) and had 64% sensitivity at 90% specificity alone and 91% sensitivity and 95% specificity if combined with CA125. CONCLUSIONS: Haptoglobin-derived alpha subunit is a potential marker for ovarian cancer that is complementary to CA125. MS-based protein profiling is a valuable tool for screening protein markers and useful to detect post-translational modification of tumor-associated proteins or abnormal metabolic products. However, confirmation of protein identity with specific antibodies is crucial for clinical application and functional studies. 相似文献
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59.