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31.
Hypoxia increases the expression of enamel genes and cytokines in an ameloblast‐derived cell line 下载免费PDF全文
Rivan Sidaly Maria A. Landin Zhenhe Suo Malcolm L. Snead Ståle P. Lyngstadaas Janne E. Reseland 《European journal of oral sciences》2015,123(5):335-340
The aim of this study was to investigate the effect of hypoxic conditions on the expression of enamel genes and on the secretion of alkaline phosphatase (ALP), lactate dehydrogenase (LDH), cytokines, and interleukins by an ameloblast‐derived cell line. Murine ameloblast‐derived cells (LS‐8 cells) were exposed to 1% oxygen for 24 and 48 h and harvested after 1, 2, 3, and 7 d. The effect of culture in hypoxic conditions on the expression of structural enamel matrix genes and on the secretion of cytokines and interleukins, as well as ALP and LDH, into the cell‐culture medium was calculated relative to the expression and secretion of these factors by untreated cells (controls) at each time point. Hypoxia increased expression of the structural enamel matrix genes amelogenin (Amelx), ameloblastin (Ambn), and enamelin (Enam), and the enamel protease matrix metalloproteinase‐20 (Mmp20). Expression of hypoxia‐inducible factor 1‐alpha (Hif1α), and secretion of several vascularization factors and pro‐inflammatory factors, were increased after 24 and 48 h of hypoxia. The ALP activity was reduced after 24 and 48 h of hypoxia, whereas the LDH level in the cell‐culture medium was higher after 24 h of hypoxic conditions compared with 48 h. In conclusion, hypoxic exposure may disrupt the controlled fine‐tuned expression and processing of enamel genes, and promote the secretion of pro‐inflammatory factors. 相似文献
32.
Janne Pleidrup Andersen Liselotte R. Norup Tina S. Dalgaard Lisa Rothwell Pete Kaiser Anders Permin 《Avian pathology》2013,42(3):276-282
In chickens, the nematode Ascaridia galli is found with prevalences of up to 100% causing economic losses to farmers. No avian nematode vaccines have yet been developed and detailed knowledge about the chicken immune response towards A. galli is therefore of great importance. The objective of this study was to evaluate the induction of protective immune responses to A. galli soluble antigen by different immunization routes. Chickens were immunized with a crude extract of A. galli via an oral or intra-muscular route using cholera toxin B subunit as adjuvant and subsequently challenged with A. galli. Only chickens immunized via the intra-muscular route developed a specific A. galli antibody response. Frequencies of γδ T cells in spleen were higher 7 days after the first immunization in both groups but only significantly so in the intra-muscularly immunized group. In addition, systemic immunization had an effect on both Th1 and Th2 cytokines in caecal tonsils and Meckel's diverticulum. Thus both humoral and cellular immune responses are inducible by soluble A. galli antigen, but in this study no protection against the parasite was achieved. 相似文献
33.
Sonita Afschar Janne M. Toivonen Julia Marianne Hoffmann Luke Stephen Tain Daniela Wieser Andrew John Finlayson Yasmine Driege Nazif Alic Sahar Emran Julia Stinn Jenny Froehlich Matthew D. Piper Linda Partridge 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(5):1321-1326
34.
Sillanaukee P Kääriäinen J Sillanaukee P Poutanen P Seppä K 《Alcoholism, clinical and experimental research》2002,26(9):1359-1364
Background To study the occurrence and documentation of substance use related outpatient visits in specialized health care.
Methods The diagnosis recorded in retrospective discharge data in Tampere University Hospital for 6 years was compared with the prospective data gathered from separately completed forms added during an 8-week period to every outpatient's discharge data. In this form, the relation of substance use and the actual reason for the consultation were specifically elicited.
Results On the basis of diagnoses, retrospectively, 0.4% (6,666 of 1,555,898) of outpatient visits were caused by substance use. In the prospective part of the study, 5.6% of visits (1,401/25,014) were related to substance use. Retrospective study demonstrated 2% prevalence of substance use, whereas prospective study showed 36% substance use–related visits at the emergency room. According to the retrospective discharge data, alcohol-related organ damages were the major reason for substance use–related outpatient visits. In the prospective study, the proportion of acute traumas was most prevalent.
Conclusions Our study indicates that substance use–related visits often remain undetected in specialized health care. Substance use–related visits were underdocumented/undetected in the emergency room. Using a simple separate form could dramatically increase the detection of substance use–related visits. 相似文献
Methods The diagnosis recorded in retrospective discharge data in Tampere University Hospital for 6 years was compared with the prospective data gathered from separately completed forms added during an 8-week period to every outpatient's discharge data. In this form, the relation of substance use and the actual reason for the consultation were specifically elicited.
Results On the basis of diagnoses, retrospectively, 0.4% (6,666 of 1,555,898) of outpatient visits were caused by substance use. In the prospective part of the study, 5.6% of visits (1,401/25,014) were related to substance use. Retrospective study demonstrated 2% prevalence of substance use, whereas prospective study showed 36% substance use–related visits at the emergency room. According to the retrospective discharge data, alcohol-related organ damages were the major reason for substance use–related outpatient visits. In the prospective study, the proportion of acute traumas was most prevalent.
Conclusions Our study indicates that substance use–related visits often remain undetected in specialized health care. Substance use–related visits were underdocumented/undetected in the emergency room. Using a simple separate form could dramatically increase the detection of substance use–related visits. 相似文献
35.
Julia Forstenpointner MD Violetta C. Oberlojer MD Dennis Naleschinski MD Johanna Höper MD Stephanie M. Helfert MD Andreas Binder MD PhD Janne Gierthmühlen MD PhD Ralf Baron MD PhD 《Pain practice》2018,18(6):758-767
Cold hyperalgesia is a common side effect of oxaliplatin treatment; still, the pathophysiological and molecular mechanisms as well as the contribution of different primary afferent fiber systems are unclear. Therefore, patients with oxaliplatin‐induced acute neuropathy with (n = 6) and without (n = 7) cold hyperalgesia were tested by applying a preferential blockade of peripheral myelinated A‐fiber afferents in combination with quantitative sensory testing. Additionally, an interview‐based questionnaire assessed the severity of symptoms and the impact on daily activities. Results indicate a deficit of cold perception in patients without cold hyperalgesia compared to patients with cold hyperalgesia prior to A‐fiber blockade. In patients with cold hyperalgesia, a preferential blockade of A‐fibers abolished cold hyperalgesia. This suggests that oxaliplatin‐induced cold hyperalgesia is mediated by A‐fibers and that a deficit in A‐fiber function might prevent the development of cold hyperalgesia. The work supports findings in rodents and in human sural nerve biopsies indicating that oxaliplatin interferes with axonal ion conductance in intact A‐fibers by sensitizing potassium and/or sodium channels. Drugs that act on these molecular targets might be of potential value to treat oxaliplatin‐induced cold hyperalgesia. 相似文献
36.
E Katriina Tarkiainen Aleksi Tornio Mikko T Holmberg Terhi Launiainen Pertti J Neuvonen Janne T Backman Mikko Niemi 《British journal of clinical pharmacology》2015,80(5):1131-1138
Aim
The aim of the present study was to investigate the effects of the carboxylesterase 1 (CES1) c.428G > A (p.G143E, rs71647871) single nucleotide variation (SNV) on the pharmacokinetics of quinapril and enalapril in a prospective genotype panel study in healthy volunteers.Methods
In a fixed-order crossover study, 10 healthy volunteers with the CES1 c.428G/A genotype and 12 with the c.428G/G genotype ingested a single 10 mg dose of quinapril and enalapril with a washout period of at least 1 week. Plasma concentrations of quinapril and quinaprilat were measured for up to 24 h and those of enalapril and enalaprilat for up to 48 h. Their excretion into the urine was measured from 0 h to 12 h.Results
The area under the plasma concentration–time curve from 0 h to infinity (AUC0–∞) of active enalaprilat was 20% lower in subjects with the CES1 c.428G/A genotype than in those with the c.428G/G genotype (95% confidence interval of geometric mean ratio 0.64, 1.00; P = 0.049). The amount of enalaprilat excreted into the urine was 35% smaller in subjects with the CES1 c.428G/A genotype than in those with the c.428G/G genotype (P = 0.044). The CES1 genotype had no significant effect on the enalaprilat to enalapril AUC0–∞ ratio or on any other pharmacokinetic or pharmacodynamic parameters of enalapril or enalaprilat. The CES1 genotype had no significant effect on the pharmacokinetic or pharmacodynamic parameters of quinapril.Conclusions
The CES1 c.428G > A SNV decreased enalaprilat concentrations, probably by reducing the hydrolysis of enalapril, but had no observable effect on the pharmacokinetics of quinapril. 相似文献37.
Janne Hukkanen Johanna Puurunen Tuulia Hy?tyl?inen Markku J Savolainen Aimo Ruokonen Laure Morin-Papunen Matej Ore?i? Terhi Piltonen Juha S Tapanainen 《British journal of clinical pharmacology》2015,80(3):473-479
Aims
Atorvastatin is known to both inhibit and induce the cytochrome P450 3A4 (CYP3A4) enzyme in vitro. Some clinical studies indicate that atorvastatin inhibits CYP3A4 but there are no well-controlled longer term studies that could evaluate the inducing effect of atorvastatin. We aimed to determine if atorvastatin induces or inhibits CYP3A4 activity as measured by the 4β-hydroxycholesterol to cholesterol ratio (4βHC : C).Methods
In this randomized, double-blind, placebo-controlled 6 month study we evaluated the effects of atorvastatin 20 mg day−1 (n = 15) and placebo (n = 14) on oxysterol concentrations and determined if atorvastatin induces or inhibits CYP3A4 activity as assessed by the 4βHC : C index. The respective 25-hydroxycholesterol and 5α,6α-epoxycholesterol ratios were used as negative controls.Results
Treatment with atorvastatin decreased 4βHC and 5α,6α-epoxycholesterol concentrations by 40% and 23%, respectively. The mean 4βHC : C ratio decreased by 13% (0.214 ± 0.04 to 0.182 ± 0.04, P = 0.024, 95% confidence interval (CI) of the difference –0.0595, –0.00483) in the atorvastatin group while no significant change occurred in the placebo group. The difference in change of 4βHC : C between study arms was statistically significant (atorvastatin –0.032, placebo 0.0055, P = 0.020, 95% CI of the difference –0.069, –0.0067). The ratios of 25-hydroxycholesterol and 5α,6α-epoxycholesterol to cholesterol did not change.Conclusions
The results establish atorvastatin as an inhibitor of CYP3A4 activity. Furthermore, 4βHC : C is a useful index of CYP3A4 activity, including the conditions with altered cholesterol concentrations. 相似文献38.
Noriaki Moriyama Teemu Laakso Peter Raivio Sebastian Dahlbacka Eeva-Maija Kinnunen Tatu Juvonen Antti Valtola Annastiina Husso Maina P. Jalava Tuomas Ahvenvaara Tuomas Tauriainen Jarkko Piuhola Asta Lahtinen Matti Niemelä Timo Mäkikallio Marko Virtanen Pasi Maaranen Markku Eskola Mika Laine 《The Canadian journal of cardiology》2021,37(1):37-46
BackgroundThe data on acute kidney injury (AKI) in patients without chronic kidney disease (CKD) after transcatheter aortic valve replacement (TAVR) are limited. The study sought to compare the incidence of AKI and its impact on 5-year mortality after TAVR and surgical aortic valve replacement (SAVR) in patients without CKD.MethodsThis registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m2. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. For sensitivity analysis, propensity-score matching between TAVR and SAVR was performed.ResultsThe study included 4555 consecutive patients (TAVR, n = 1215 and SAVR, n = 3340) without CKD. Propensity-score matching identified 542 pairs. Patients who underwent TAVR had a significantly lower incidence of AKI in comparison to those who underwent SAVR (unmatched 4.7% vs 16.4%, P < 0.001, multivariable analysis: odds ratio, 0.29, 95% confidence interval [CI], 0.20-0.41; matched 5.9% vs 19.0%, P < 0.001). Patients with AKI had significantly increased 5-year mortality compared with those without AKI (unmatched 36.0% vs 19.1%, log-rank P < 0.001; matched 36.3% vs 24.0%, log-rank P < 0.001). The adjusted hazard ratios for 5-year mortality were 1.58 (95% CI, 1.20-2.08) for AKI grade 1, 3.27 (95% CI, 2.09-5.06) for grade 2, and 4.82 (95% CI, 2.93-8.04) for grade 3.ConclusionsTAVR in patients without CKD was associated with a significantly less frequent incidence of AKI compared with SAVR. AKI significantly increased the risk of 5-year mortality after either TAVR or SAVR, and increasing severity of AKI was incrementally associated with 5-year mortality. 相似文献
39.
40.
Chipanta David Pettifor Audrey Edwards Jessie Giovenco Danielle Topazian Hillary Mariko Bray Rachel M. Millington Monique C. Estill Janne Keiser Olivia Justman Jessica E. 《AIDS and behavior》2022,26(9):3068-3078
AIDS and Behavior - We aimed to measure social protection coverage among the general population, women and men living with HIV (WLHIV, MLHV), female and male sex workers (FSW, MSW), men who have... 相似文献