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61.
Rapid decline of chronic myeloid leukemic cells in long-term culture due to a defect at the leukemic stem cell level. 总被引:9,自引:0,他引:9 下载免费PDF全文
C Udomsakdi C J Eaves B Swolin D S Reid M J Barnett A C Eaves 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(13):6192-6196
In this report we describe a quantitative in vitro assay for the most primitive type of leukemic precursors yet defined in patients with chronic myeloid leukemia (CML). This assay is based on the recently described "long-term culture-initiating cell" (LTC-IC) assay for primitive normal human hematopoietic cells. Such cells, when cocultured with competent fibroblast feeder layers, give rise after a minimum of 5 weeks to multiple single and multilineage clonogenic progenitors detectable in secondary semisolid assay cultures. Similar cultures initiated by seeding a highly enriched source of leukemic cells from patients onto normal feeders showed the clonogenic cell output after 5 weeks to be linearly related to the input innoculum over a wide range down to limiting numbers of input cells, thus allowing absolute frequencies of leukemic LTC-ICs to be determined using standard limiting dilution analysis techniques. Leukemic LTC-IC concentrations in CML marrow were found to be decreased, on average to less than 10% of the normal LTC-IC concentration in normal marrow, but were greatly increased (up to greater than 10(5) times) in CML blood. Assessment of the number of clonogenic cells produced per leukemic LTC-IC by comparison to normal blood or marrow LTC-IC values showed this function to be unchanged in leukemic LTC-ICs [i.e., 3.1 +/- 0.4 clonogenic cells per CML LTC-IC (mean +/- SEM, n = 6) versus 3.7 +/- 1.2 (n = 3) and 4.3 +/- 0.4 (n = 5), respectively, for normal blood and marrow LTC-ICs]. In contrast, leukemic LTC-IC maintenance in LTC proved to be highly defective by comparison to normal LTC-IC of either blood or marrow origin. Thus, when cells from primary LTC were subcultured into secondary LTC-IC assays, leukemic LTC-IC rapidly declined (greater than 30-fold) within the first 10 days of culture, whereas normal LTC-IC numbers remained unchanged during this period. These findings illustrate how self-maintenance and differentiation events in primitive human hematopoietic cells can be differentially modulated by an oncogenic process and provide a framework for further studies of their manipulation, analysis, and therapeutic exploitation. 相似文献
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Birgitta Bergendal Merete Bakke Anita McAllister Lotta Sjögreen Pamela Åsten 《Acta odontologica Scandinavica》2014,72(8):578-584
Objective. The Nordic Orofacial Test-Screening (NOT-S) was developed as a comprehensive method to assess orofacial function. Results from the screening protocol have been presented in 11 international publications to date. This study reviewed these publications in order to compile NOT-S screening data and create profiles of orofacial dysfunction that characterize various age groups and disorders. Materials and methods. NOT-S results of nine reports meeting the inclusion criteria were reviewed. Seven of these studies not only provided data on the mean and range of total NOT-S scores, but also on the most common domains of orofacial dysfunction (highest rate of individuals with dysfunction scores), allowing the construction of orofacial dysfunction profiles based on the prevalence of dysfunction in each domain of NOT-S. Results. The compiled data comprised 669 individuals, which included healthy control subjects (n = 333) and various patient groups (n = 336). All studies reported differences between individuals with diagnosed disorders and healthy control subjects. The NOT-S data could measure treatment effects and provided dysfunction profiles characterizing the patterns of orofacial dysfunction in various diagnoses. Conclusions. This review corroborates previous results that the NOT-S differentiates well between patients and healthy controls and can also show changes in individuals after treatment. NOT-S could be used as a standard instrument to assess orofacial dysfunction, evaluate the outcomes of oral habilitation and rehabilitation and improve comparability in clinical practice and research. 相似文献
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Identification of functional prolactin (PRL) receptor gene expression: PRL inhibits lipoprotein lipase activity in human white adipose tissue 总被引:1,自引:0,他引:1
Ling C Svensson L Odén B Weijdegård B Edén B Edén S Billig H 《The Journal of clinical endocrinology and metabolism》2003,88(4):1804-1808
During lactation serum levels of prolactin (PRL) are elevated, and the activity of lipoprotein lipase (LPL) is decreased in the adipose tissue and increased in the mammary gland. However, PRL has been suggested to affect the adipose tissue in an indirect fashion during lactation. In the present study, we demonstrated expression of four PRL receptor (PRLR) mRNA isoforms (L, I, S1(a), and S1(b)) in human sc abdominal adipose tissue and breast adipose tissue using RT-PCR/Southern blot analysis. In addition, L-PRLR [relative molecular mass (M(r)) 90,000] and I-PRLR (M(r) 50,000) protein expression was detected in human sc abdominal adipose tissue and breast adipose tissue using immunoblot analysis. Two additional protein bands with the molecular weight M(r) 40-35,000 were also detected. The direct effect of PRL on the regulation of LPL activity in human abdominal adipose tissue cultured in vitro was investigated. PRL (500 ng/ml) reduced the LPL activity in human adipose tissue to 31 +/- 7.7%, compared with control. GH (100 ng/ml) also reduced the LPL activity, to 45 +/- 8.6%, compared with control. In agreement with previous studies, cortisol increased the LPL activity and GH inhibited cortisol-induced LPL activity. Furthermore, we found that PRL also inhibited the cortisol-induced LPL activity. Taken together, these results demonstrate a direct effect of PRL, via functional PRLRs, in reducing the LPL activity in human adipose tissue, and these results suggest that LPL might also be regulated in this fashion during lactation. 相似文献
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Species-specific DNA probes were used to determine the presence of Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas (Bacteroides) gingivalis, Prevotella intermedia, Treponema denticola. Eikenella corrodens, Fusobacterium nucleatum , and Wolinella recta in subgingival plaque from deep pockets/sites of patients with advanced periodontitis. The subjects were 20 patients with severe adult periodontitis, 13 men and 7 women (mean age 45.6 ± 6.7 yr). For each subject, 9–10 subgingival sites with the deepest probing depths from each quadrant were sampled by the paper point method, a total of 198 sites, with mean probing depth 7.2 ± 1.6 mm and clinical attachment level 9.5 ± 2.7 mm. A.a . was present in at least one site in 75% of the subjects; P. gingivalis was found in 95%; P. intermedia and W. recta were found in 90%, respectively; and T. denticola, E. corrodens , and F. nucleatum were found in all subjects. In the 198 samples, A.a . was detected in 25.8%, P. gingivalis in 51.5%, P. intermedia in 64.1%, T. denticola in 60.6%, E. corrodens in 72.9%, F. nucleatum in 74.7%, and W. recta in 65.7%. The predominant combination was the simultaneous presence of P. intermedia, T. denticola, E. corrodens, F. nucleatum , and W. recta in 89.5% of the subjects and 46.8% of the sites. Of these sites, 51.1% showed the combined presence of P. gingivalis and 28.4% that of both A.a . and P. gingivalis . None of the seven bacteria could be detected in 14.4% of the total sites sampled. The present study indicates that severe destructive adult periodontitis is a multibacterial infection and that certain combinations of periodontopathogens seein to be important in the pathogenesis of the disease. 相似文献
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Cigarette smoking,snuff use and alcohol drinking: coexisting risk behaviours for oral health in young males 总被引:1,自引:0,他引:1
Wickholm S Galanti MR Söder B Gilljam H 《Community dentistry and oral epidemiology》2003,31(4):269-274
OBJECTIVES: The use of oral moist snuff (snus) is widespread among Swedish men, but little is known about the use in adolescents. The aim of this study was to describe patterns of snuff dipping, smoking and alcohol drinking in a sample (n = 6287) of 9th grade male students participating in a census survey in the Stockholm region. RESULTS: About 20% of the sample reported use of snus, and more than two-thirds of snus users were also cigarette smokers. Among current nonusers of tobacco (66% of the sample), 14% reported frequent binge drinking, in contrast to 49% among current exclusive cigarette smokers, 60% among exclusive snus users and 69% among users of both cigarettes and snus. The estimated mean annual consumption of alcohol was 5-10 times higher among tobacco users than among nonusers, with users of snus consuming more alcohol than smokers. Compared to non- or minimal drinkers, heavy alcohol drinkers had a disproportionately higher risk to report snus use, after adjustment for smoking behaviour (OR = 16.7, 95% CI 12.9-21.7). When the analysis was restricted to users of only one type of tobacco, heavy drinkers were twice as likely to report snus, rather than cigarette, use. CONCLUSIONS: Both tobacco use and alcohol drinking have been independently associated with a variety of pathological oral conditions in adults. These behaviours coexist in early adolescence. Their effect on oral health need to be investigated in prospective studies and should be of concern to the dental professionals. 相似文献
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