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113.
Fava G Ueno Y Glaser S Francis H Demorrow S Marucci L Marzioni M Benedetti A Venter J Vaculin B Vaculin S Alpini G 《American journal of physiology. Cell physiology》2007,292(4):C1467-C1475
The role of the thyroid hormone agonist 3,3',5 L-tri-iodothyronine (T3) on cholangiocytes is unknown. We evaluated the in vivo and in vitro effects of T3 on cholangiocyte proliferation of bile duct-ligated (BDL) rats. We assessed the expression of 1-, 2-, 1-, and 2-thyroid hormone receptors (THRs) by immunohistochemistry in liver sections from normal and BDL rats. BDL rats were treated with T3 (38.4 µg/day) or vehicle for 1 wk. We evaluated 1) biliary mass and apoptosis in liver sections and 2) proliferation in cholangiocytes. Serum-free T3 levels were measured by chemiluminescence. Purified BDL cholangiocytes were treated with 0.2% BSA or T3 (1 µM) in the absence/presence of U-73122 (PLC inhibitor) or BAPTA/AM (intracellular Ca2+ chelator) before measurement of PCNA protein expression by immunoblots. The in vitro effects of T3 (1 µM) on 1) cAMP, IP3, and Ca2+ levels and 2) the phosphorylation of Src Tyr139 and Tyr530 (that, together, regulate Src activity) and ERK1/2 of BDL cholangiocytes were also evaluated. 1-, 2-, 1-, and 2-THRs were expressed by bile ducts of normal and BDL rats. In vivo, T3 decreased cholangiocyte proliferation of BDL rats. In vitro, T3 inhibition of PCNA protein expression was blocked by U-73122 and BAPTA/AM. Furthermore, T3 1) increased IP3 and Ca2+ levels and 2) decreased Src and ERK1/2 phosphorylation of BDL cholangiocytes. T3 inhibits cholangiocyte proliferation of BDL rats by PLC/IP3/Ca2+-dependent decreased phosphorylation of Src/ERK1/2. Activation of the intracellular signals triggered by T3 may modulate the excess of cholangiocyte proliferation in liver diseases. cholestasis; cholangiopathies; hyperplasia; intrahepatic biliary epithelium; mitosis 相似文献
114.
Jorit JL Meesters Ann Bremander Stefan Bergman Ingemar F Petersson Aleksandra Turkiewicz Martin Englund 《Arthritis research & therapy》2014,16(5)
Introduction
Depression is frequent in ankylosing spondylitis (AS) patients. However, epidemiological data about the potential increase in risk are lacking. This study compares the rate of doctor-diagnosed depression in a well defined cohort of AS patients to the general population seeking care.Methods
The Skåne Healthcare Register comprises healthcare data of each resident in Region Skåne, Sweden (population 1.2 million), including ICD-10 diagnoses. Using physician coded consultation data from years 1999 to 2011, we calculated depression consultation rates for all AS patients. We obtained standardized depression-rate ratios by dividing the observed depression rate in AS patients by the expected rate based on the corresponding age- and sex-specific rates of depression in the general population seeking care. A ratio >1 equals a higher rate of depression among AS patients.Results
The AS cohort consisted of 1738 subjects (65% men) with a mean age of 54 years. The reference population consisted of 967,012 subjects. During the 13-year observation period 10% (n = 172) of the AS cohort had a doctor-diagnosed depression compared to 6% (n = 105) to be expected. The standardized estimate of depression-rate ratio was 1.81 (95% confidence interval 1.44 to 2.24) in women men and 1.49 (1.20 to 1.89) in men.Conclusions
The rate of doctor-diagnosed depression is increased about 80% in female and 50% in male AS patients. Future challenges are to timely identify and treat the AS patients who suffer from depression. 相似文献115.
Background
The leukocyte common antigen related receptor (LAR) protein has been shown to modulate the signal transduction of a number of different growth factors, including insulin and insulin-like growth factor 1. Splice variants exhibit differing roles and are expressed according to tissue type and developmental stage. 相似文献116.
Esther Heikens Masja Leendertse Lucas M Wijnands Miranda van Luit-Asbroek Marc JM Bonten Tom van der Poll Rob JL Willems 《BMC microbiology》2009,9(1):19-7
Background
Enterococcus faecium has globally emerged as a cause of hospital-acquired infections with high colonization rates in hospitalized patients. The enterococcal surface protein Esp, identified as a potential virulence factor, is specifically linked to nosocomial clonal lineages that are genetically distinct from indigenous E. faecium strains. To investigate whether Esp facilitates bacterial adherence and intestinal colonization of E. faecium, we used human colorectal adenocarcinoma cells (Caco-2 cells) and an experimental colonization model in mice. 相似文献117.
Sara Di Toro Giulio Zanaroli Giovanna Cristina Varese Valeria Filipello Marchisio Fabio Fava 《International biodeterioration & biodegradation》2008,62(2):153-161
The biodegradability of two commercial diesel fuels, i.e., Diesel and HiQ Diesel, herewith designated as G1 and G2, respectively, spiked to an agricultural soil at 10 g kg−1 was studied under aerobic slurry-phase conditions in the absence and in the presence of Enzyveba, i.e., a characterized commercial source of microorganisms and nutrients. A quite similar hydrocarbon composition was displayed by G1 and G2, which were found to be both extensively and almost completely biodegraded under all conditions after 4.5 months of treatment with a remarkable depletion of initial soil ecotoxicity, in particular in the G2 spiked one. The addition of Enzyveba resulted in a higher availability of cultivable specialized bacteria and fungi in the reactors but this only resulted in a slight intensification of soil bioremediation, probably because of the high contents of nutrients and indigenous specialized microorganisms of the soil. A faster biodegradation of hydrocarbons and a more rapid and extensive depletion of initial ecotoxicity were generally observed in the soil reactors spiked with G2 with respect to those spiked with G1 probably for the G2 content of additives capable of improving hydrocarbons bioavailability. 相似文献
118.
Makris N Gasic GP Kennedy DN Hodge SM Kaiser JR Lee MJ Kim BW Blood AJ Evins AE Seidman LJ Iosifescu DV Lee S Baxter C Perlis RH Smoller JW Fava M Breiter HC 《Neuron》2008,60(1):174-188
The structural effects of cocaine on neural systems mediating cognition and motivation are not well known. By comparing the thickness of neocortical and paralimbic brain regions between cocaine-dependent and matched control subjects, we found that four of 18 a priori regions involved with executive regulation of reward and attention were significantly thinner in addicts. Correlations were significant between thinner prefrontal cortex and reduced keypresses during judgment and decision making of relative preference in addicts, suggesting one basis for restricted behavioral repertoires in drug dependence. Reduced effortful attention performance in addicts also correlated with thinner paralimbic cortices. Some thickness differences in addicts were correlated with cocaine use independent of nicotine and alcohol, but addicts also showed diminished thickness heterogeneity and altered hemispheric thickness asymmetry. These observations suggest that brain structure abnormalities in addicts are related in part to drug use and in part to predisposition toward addiction. 相似文献
119.
120.
Di Gioia D Michelles A Pierini M Bogialli S Fava F Barberio C 《Journal of applied microbiology》2008,104(1):231-242
Aims: Isolation and characterization of new bacterial strains capable of degrading nonylphenol ethoxylates (NP n EO) with a low ethoxylation degree, which are particularly recalcitrant to biodegradation.
Methods and Results: Seven aerobic bacterial strains were isolated from activated sludges derived from an Italian plant receiving NP n EO-contaminated wastewaters after enrichment with a low-ethoxylated NP n EO mixture. On the basis of 16S rDNA sequence, the strains were positioned into five genera: Ochrobactrum , Castellaniella , Variovorax , Pseudomonas and Psychrobacter . Their degradation capabilities have been evaluated on two commercial mixtures, i.e. Igepal CO-210 and Igepal CO-520, the former rich in low ethoxylated congeners and the latter containing a broader spectrum of NP n EO, and on 4- n -nonylphenol (NP). The strains degraded Igepal CO-210, Igepal CO-520 and 4- n -NP all applied at the initial concentration of 100 mg l−1 , by 35–75%, 35–90% and 15–25%, respectively, after 25 days of incubation.
Conclusions: Some of the isolated strains, in particular the Pseudomonas strains BCb12/1 and BCb12/3, showed interesting degradation capabilities towards low ethoxylated NP n EO congeners maintaining high cell vitality.
Significance and Impact of the Study: Increased knowledge of bacteria involved in NP n EO degradation and the possibility of using the isolated strains in tailored process for a tertiary biological treatment of effluents of wastewater treatment plants. 相似文献
Methods and Results: Seven aerobic bacterial strains were isolated from activated sludges derived from an Italian plant receiving NP n EO-contaminated wastewaters after enrichment with a low-ethoxylated NP n EO mixture. On the basis of 16S rDNA sequence, the strains were positioned into five genera: Ochrobactrum , Castellaniella , Variovorax , Pseudomonas and Psychrobacter . Their degradation capabilities have been evaluated on two commercial mixtures, i.e. Igepal CO-210 and Igepal CO-520, the former rich in low ethoxylated congeners and the latter containing a broader spectrum of NP n EO, and on 4- n -nonylphenol (NP). The strains degraded Igepal CO-210, Igepal CO-520 and 4- n -NP all applied at the initial concentration of 100 mg l
Conclusions: Some of the isolated strains, in particular the Pseudomonas strains BCb12/1 and BCb12/3, showed interesting degradation capabilities towards low ethoxylated NP n EO congeners maintaining high cell vitality.
Significance and Impact of the Study: Increased knowledge of bacteria involved in NP n EO degradation and the possibility of using the isolated strains in tailored process for a tertiary biological treatment of effluents of wastewater treatment plants. 相似文献