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1.
2.
The association between diabetes and hepatocellular carcinoma: a systematic review of epidemiologic evidence. 总被引:2,自引:0,他引:2
Hashem B El-Serag Howard Hampel Fariba Javadi 《Clinical gastroenterology and hepatology》2006,4(3):369-380
BACKGROUND & AIMS: We conducted a systematic review and a meta-analysis to estimate the magnitude and determinants of association between diabetes and hepatocellular carcinoma (HCC). METHODS: MEDLINE searches were conducted for published full studies (between January 1966 and February 2005) that provided risk estimates and met criteria concerning the definition of exposure and outcomes. Two investigators independently performed standardized search and data abstraction. Unadjusted and adjusted odds ratios for individual outcomes were obtained or calculated for each study and were synthesized using a random-effects model. RESULTS: A total of 26 studies met our inclusion and exclusion criteria. Among 13 case-control studies, diabetes was associated significantly with HCC in 9 studies (pooled odds ratio, 2.5; 95% confidence interval, 1.8-3.5). Among 13 cohort studies, diabetes was associated significantly with HCC in 7 studies (pooled risk ratio, 2.5; 95% confidence interval, 1.9-3.2). The results were relatively consistent in different populations, different geographic locations, and a variety of control groups. The significant association between HCC and diabetes was independent of alcohol use or viral hepatitis in the 10 studies that examined these factors. Few studies adjusted for diet and obesity. CONCLUSIONS: Diabetes is associated with an increased risk for HCC. However, more research is required to examine issues related to the duration and treatment of diabetes, and confounding by diet and obesity. 相似文献
3.
CARLOS HOYO-VADILLO JOS PREZ-URIZAR FRANCISCO J. L
PEZ-MU
OZ 《The Journal of pharmacy and pharmacology》1995,47(6):462-465
In this work we show that the pain-induced functional impairment model (PIFIR) can be used with cannulated rats as a useful procedure for pharmacokinetic/pharmacodynamic modelling. This model evaluates analgesia by measuring motor impairment of the right limb after intra-articular administration of uric acid. Time of contact with a rotating cylinder is referred to the control limb. We studied the pharmacokinetic and pharmacodynamics of naproxen after six peroral doses to Wistar rats, and we examined the adjuvant action of caffeine with naproxen. Surgery and blood sampling did not produce any difference on functional impairment either in rats without uric acid or in the dysfunction produced by uric acid. The relation between naproxen plasma concentration and the analgesic effect was obtained with few rats. Caffeine alone did not produce any significant modification in functional impairment but the co-administration significantly increased the effect of naproxen. Plasma levels of naproxen did not change when caffeine was co-administered. The PIFIR model with blood sampling is a suitable method for pharmacokinetic/pharmacodynamic relationship studies and is specially useful to characterize drug-drug interactions. 相似文献
4.
Gropp E Shanabrough M Borok E Xu AW Janoschek R Buch T Plum L Balthasar N Hampel B Waisman A Barsh GS Horvath TL Brüning JC 《Nature neuroscience》2005,8(10):1289-1291
Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis. 相似文献
5.
Johansson A Hampel H Faltraco F Buerger K Minthon L Bogdanovic N Sjögren M Zetterberg H Forsell L Lilius L Wahlund LO Rymo L Prince JA Blennow K 《Neuroscience letters》2003,340(1):69-73
Recent studies show linkage between Alzheimer's disease (AD) and two loci on chromosome 10. The cell division cycle 2 (cdc2) gene is located close to one of the chromosome 10 markers, and is a candidate gene for AD since it is involved in the pathogenesis of AD. We sequenced coding exons and flanking intronic sequences and the promoter region on the cdc2 gene and found three new single nucleotide polymorphisms (SNPs). We analyzed 272 Caucasian AD cases, 160 controls and 70 cases with frontotemporal dementia (FTD) for these SNPs. Homozygosity for one of the SNPs (Ex6+7I/D) was more frequent in both AD and FTD cases than in controls. In the combined tauopathy (AD and FTD) group the odds ratio (OR) was 1.77 (95% CI 1.19-2.63) for the Ex6+7II genotype. Our findings suggest that the Ex6+7I allele is associated with tauopathies, both AD and FTD. 相似文献
6.
Genetic ablation of FLRT3 reveals a novel morphogenetic function for the anterior visceral endoderm in suppressing mesoderm differentiation 总被引:1,自引:0,他引:1
Joaquim Egea Christian Erlacher Eloi Montanez Ingo Burtscher Satoru Yamagishi Martin Heß Falko Hampel Rodrigo Sanchez Maria Teresa Rodriguez-Manzaneque Michael R. Bsl Reinhard Fssler Heiko Lickert Rüdiger Klein 《Genes & development》2008,22(23):3349-3362
During early mouse development, the anterior visceral endoderm (AVE) secretes inhibitor and activator signals that are essential for establishing the anterior–posterior (AP) axis of the embryo and for restricting mesoderm formation to the posterior epiblast in the primitive streak (PS) region. Here we show that AVE cells have an additional morphogenetic function. These cells express the transmembrane protein FLRT3. Genetic ablation of FLRT3 did not affect the signaling functions of the AVE according to the normal expression pattern of Nodal and Wnt and the establishment of a proper AP patterning in the epiblast. However, FLRT3−/− embryos showed a highly disorganized basement membrane (BM) in the AVE region. Subsequently, adjacent anterior epiblast cells displayed an epithelial-to-mesenchymal transition (EMT)-like process characterized by the loss of cell polarity, cell ingression, and the up-regulation of the EMT and the mesodermal marker genes Eomes, Brachyury/T, and FGF8. These results suggest that the AVE acts as a morphogenetic boundary to prevent EMT and mesoderm induction in the anterior epiblast by maintaining the integrity of the BM. We propose that this novel function cooperates with the signaling activities of the AVE to restrict EMT and mesoderm induction to the posterior epiblast. 相似文献
7.
Darouiche RO Hampel OZ Boone TB Raad II 《International journal of antimicrobial agents》1997,8(4):243-247
The main objective of this study was to examine the antimicrobial activity and durability of a novel indwelling bladder catheter impregnated with minocycline and rifampin. Thirty antimicrobial-impregnated bladder catheters were inserted transurethrally in spinal cord-injured patients and removed, in six groups of five catheters each, at 3, 7, 10, 14, 17 or 21 days. Removed catheters had detectable zones of inhibition against two different clinical isolates of each of the 10 tested uropathogens (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter diversus, Enterococcus faecalis, Enterococcus faecium, Staphylococcus saprophyticus and Candida albicans) for greater than 14 days after catheter insertion. The residual zones of inhibition and levels of antimicrobial agents in removed catheters were both inversely related to the duration of catheter placement. Minocycline and rifampin were undetectable in serum and urine. These results support the ongoing efforts for examining the clinical efficacy of these experimental bladder catheters. 相似文献
8.
Teipel SJ Hampel H Pietrini P Alexander GE Horwitz B Daley E Möller HJ Schapiro MB Rapoport SI 《Archives of neurology》1999,56(4):467-473
BACKGROUND: Positron emission tomographic studies of patients with Alzheimer disease (AD) suggest a loss of metabolic functional interactions between different cortical regions. Atrophy of the corpus callosum as the major tract of intracortical connective fibers may reflect decreased cortical functional integration in AD. OBJECTIVES: To investigate whether regional atrophy of the corpus callosum is correlated with regional reductions of cortical glucose metabolism, as shown by positron emission tomography, and whether primary white matter degeneration is a possible cofactor of corpus callosum atrophy in AD. PATIENTS AND METHODS: We measured total and regional cross-sectional areas of the corpus callosum on midsagittal magnetic resonance imaging scans from 12 patients with AD and 15 age-matched control subjects. Regional cerebral metabolic rates for glucose in cortical lobes were measured by positron emission tomography using fludeoxyglucose F 18. White matter hyperintensities were rated in T2-weighted magnetic resonance imaging scans. RESULTS: The total cross-sectional area of corpus callosum was significantly reduced in patients with AD, with the most prominent changes in the rostrum and splenium and relative sparing of the body of the corpus callosum. Frontal and parietal lobe metabolism was correlated with the truncal area of the corpus callosum in AD. The ratios of frontal to parietal and of frontal to occipital metabolism were correlated with the ratio of anterior to posterior corpus callosum area in the group with AD. White matter hyperintensities did not correlate with corpus callosum atrophy in the patients with AD. CONCLUSION: The regional pattern of corpus callosum atrophy correlated with reduced regional glucose metabolism independently of primary white matter degeneration in the patients with AD. 相似文献
9.
Padberg F Zwanzger P Thoma H Kathmann N Haag C Greenberg BD Hampel H Möller HJ 《Psychiatry research》1999,88(3):163-171
In previous studies, fast repetitive transcranial magnetic stimulation (rTMS) with a frequency > 1 Hz demonstrated substantial antidepressant effects compared to sham rTMS. However, it is not clear whether fast rTMS is superior to slow rTMS (frequency < or = 1 Hz) which is safe at therapeutically promising higher intensities. The aim of this double-blind study was to compare the action of fast, slow and sham rTMS. Eighteen patients with pharmacotherapy-resistant major depression were randomized to receive fast (10 Hz), slow (0.3 Hz) or sham rTMS with 250 stimuli/day for 5 successive days. rTMS was applied at 90% motor threshold intensity to the left dorsolateral prefrontal cortex. Scores on the Hamilton Depression Rating Scale (HDRS), but not on the Montgomery-Asberg Depression Rating Scale (MADRS), showed a statistically significant time x group interaction with a reduction of 19% after slow rTMS. However, the effect was clinically marginal and not reflected by self-rating scores. Verbal memory and reaction performance were not impaired after rTMS, and there was even a statistically significant time x group interaction with improvement of verbal memory performance after fast rTMS. In conclusion, this study further supported the safety of rTMS but does not show any clinically meaningful antidepressant efficacy of rTMS at 250 daily stimuli over 5 days in pharmacotherapy-refractory major depression. 相似文献
10.
Hampel B Malisan F Niederegger H Testi R Jansen-Dürr P 《Experimental gerontology》2004,39(11-12):1713-1721
Aging of human cells can be reproduced in monolayer cultures, revealing the phenotype of replicative senescence. It was shown that diploid human fibroblasts enter a stable growth arrest phenotype at the end of their lifespan and, in particular, these cells are resistant to various apoptotic stimuli. In contrast, human endothelial cells from the umbilical vein (HUVEC) acquire a proapoptotic phenotype when reaching senescence and this probably results from reactive oxygen species (ROS) induced damage and associated signaling. Ceramides were shown to accumulate in senescent fibroblasts and are also known as potent regulators of apoptotic cell death. To further study age-associated changes in proneness to apoptosis between fibroblasts and endothelial cells, both cell types were challenged by administration of exogenous ceramide and apoptotic cell death was determined. While ceramide can efficiently induce apoptosis in both young and senescent cells of either histotype, quantitative evaluation of the data show that senescent fibroblasts are more resistant to apoptosis induction when compared to their young counterparts, whereas in the case of endothelial cells proneness for apoptosis is increased in senescent cells. Together, these data suggest significant differences in the regulation of apoptosis associated with senescence in fibroblasts and endothelial cells. 相似文献