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81.
Assessment of aldehyde dehydrogenase in viable cells 总被引:3,自引:4,他引:3
Jones RJ; Barber JP; Vala MS; Collector MI; Kaufmann SH; Ludeman SM; Colvin OM; Hilton J 《Blood》1995,85(10):2742-2746
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations. 相似文献
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83.
Erik P A van Iperen Suthesh Sivapalaratnam S Matthijs Boekholdt G Kees Hovingh Stephanie Maiwald Michael W Tanck Nicole Soranzo Jonathan C Stephens Jennifer G Sambrook Marcel Levi Willem H Ouwehand John JP Kastelein Mieke D Trip Aeilko H Zwinderman 《European journal of human genetics : EJHG》2014,22(6):809-813
In recent years, multiple loci dispersed on the genome have been shown to be associated with coronary artery disease (CAD). We investigated whether these common genetic variants also hold value for CAD prediction in a large cohort of patients with familial hypercholesterolemia (FH). We genotyped a total of 41 single-nucleotide polymorphisms (SNPs) in 1701 FH patients, of whom 482 patients (28.3%) had at least one coronary event during an average follow up of 66 years. The association of each SNP with event-free survival time was calculated with a Cox proportional hazard model. In the cardiovascular disease risk factor adjusted analysis, the most significant SNP was rs1122608:G>T in the SMARCA4 gene near the LDL-receptor (LDLR) gene, with a hazard ratio for CAD risk of 0.74 (95% CI 0.49–0.99; P-value 0.021). However, none of the SNPs reached the Bonferroni threshold. Of all the known CAD loci analyzed, the SMARCA4 locus near the LDLR had the strongest negative association with CAD in this high-risk FH cohort. The effect is contrary to what was expected. None of the other loci showed association with CAD. 相似文献
84.
Katherine JP Schwenger Johane P Allard 《World journal of gastroenterology : WJG》2014,20(7):1712-1723
Non-alcoholic fatty liver disease(NAFLD)ranges from simple steatosis to nonalcoholic steatohepatitis(NASH),leading to fibrosis and potentially cirrhosis,and it is one of the most common causes of liver disease worldwide.NAFLD is associated with other medical conditions such as metabolic syndrome,obesity,cardiovascular disease and diabetes.NASH can only be diagnosed through liver biopsy,but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis,reducing the need for liver biopsy and risk to patients.Disease progression varies between individuals and is linked to a number of risk factors.Mechanisms involved in the pathogenesis are associated with diet and lifestyle,influx of free fatty acids to the liver from adipose tissue due to insulin resistance,hepatic oxidative stress,cytokines production,reduced very low-density lipoprotein secretion and intestinal microbiome.Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD.Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial.Omega 3 polyunsaturated fatty acids and statins may offer additional benefits.Bariatric surgery should be considered in morbidly obese patients.More research is needed to assess the impact of these treatments on a long-term basis.The objective of this article is to briefly review the diagnosis,management and treatment of this disease in order to aid clinicians in managing these patients. 相似文献
85.
Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes. 相似文献
86.
87.
Gaelle Thierry Olivier Pichon Annaig Briand Damien Poulain Yves Sznajer Albert David Cédric Le Caignec 《European journal of medical genetics》2013,56(1):46-49
Unbalanced insertional translocations are a rare cause of intellectual disability. An unbalanced insertional translocation is a rare chromosomal imbalance, which may result from a balanced insertional translocation present in a phenotypically normal parent. We report here three brothers with intellectual disability, short stature, microcephaly, craniofacial anomalies and small testes. Since their parents and their sister were all phenotypically normal, the pattern of the family suggested an X-linked mode of inheritance. Surprisingly, we identified by array comparative genomic hybridization (aCGH) and fluorescent in situ hybridization (FISH) in the three brothers an 8q22.3q23.2 deletion resulting from a balanced insertional translocation present in their healthy father. The deletion encompassed the ZFPM2 gene known to be involved in gonadal development, which is consistent with the small testes and abnormal endocrine dosages in the affected brothers. The present report also illustrates that parental analyses by aCGH or qPCR methods are not sufficient when a de novo deletion or duplication is identified in an affected child and that FISH analysis should be performed on metaphase spreads in both parents to deliver an accurate genetic counseling. 相似文献
88.
Tam JS Barbeschi M Shapovalova N Briand S Memish ZA Kieny MP 《The Lancet infectious diseases》2012,12(3):231-239
Public health research is essential for the development of effective policies and planning to address health security and risks associated with mass gatherings (MGs). Crucial research topics related to MGs and their effects on global health security are discussed in this review. The research agenda for MGs consists of a framework of five major public health research directions that address issues related to reducing the risk of public health emergencies during MGs; restricting the occurrence of non-communicable and communicable diseases; minimisation of the effect of public health events associated with MGs; optimisation of the medical services and treatment of diseases during MGs; and development and application of modern public health measures. Implementation of the proposed research topics would be expected to provide benefits over the medium to long term in planning for MGs. 相似文献
89.
90.
Research on the regulation and function of ascending noradrenergic, dopaminergic, serotonergic, and cholinergic systems has focused on the organization and function of individual systems. In contrast, evidence describing co-activation and interactions between multiple neuromodulatory systems has remained scarce. However, commonalities in the anatomical organization of these systems and overlapping evidence concerning the post-synaptic effects of neuromodulators strongly suggest that these systems are recruited in concert; they influence each other and simultaneously modulate their target circuits. Therefore, evidence on the regulatory and functional interactions between these systems is considered essential for revealing the role of neuromodulators. This postulate extends to contemporary neurobiological hypotheses of major neuropsychiatric disorders. These hypotheses have focused largely on aberrations in the integrity or regulation of individual ascending modulatory systems, with little regard for the likely possibility that dysregulation in multiple ascending neuromodulatory systems and their interactions contribute essentially to the symptoms of these disorders. This review will paradigmatically focus on neuromodulator interactions in the PFC and be further constrained by an additional focus on their role in cognitive functions. Recent evidence indicates that individual neuromodulators, in addition to their general state-setting or gating functions, encode specific cognitive operations, further substantiating the importance of research concerning the parallel recruitment of neuromodulator systems and interactions between these systems. 相似文献