Impact of different guidewires on the implantation depth using the largest self-expandable TAVI device

BackgroundThe deployment process of the largest self-expandable device (STHV-34) during transcatheter aortic valve implantation (TAVI) might be challenging due to stabilization issues. Whether the use of different TAVI-guidewires impact the procedural success and outcome is not well-known. Therefore, we sought to evaluate the impact of non-Lunderquist (NLu) vs. the Lunderquist (Lu) guidewires during TAVI using the STHV-34 on the procedural and 30-day outcomes.MethodsThe primary study endpoint was defined as the final implantation depth (ID) depending on the selected guidewire strategy. Key secondary endpoints included VARC-3-defined complications.ResultsThe study cohort included 398 patients of four tertiary care institutions, of whom 79.6% (317/398) had undergone TAVI using NLu and 20.4% (81/398) using Lu guidewires. Baseline characteristics did not substantially differ between NLu and Lu patients. The average ID was higher in the Lu cohort (NLu vs. Lu: −5.2 [−7.0–(−3.5)] vs. −4.5 [−6.0–(−3.0)]; p = 0.022*). The optimal ID was reached in 45.0% of patients according to former and only in 20.1% according to nowadays best practice recommendations. There was no impact of the guidewire use on the 30-day outcomes, including conduction disturbances and pacemaker need (NLu vs. Lu: 15.1 vs. 18.5%; p = 0.706).ConclusionThe use of the LunderquistTM guidewire was associated with a higher ID during TAVI with the STHV-34 without measurable benefits in the 30-day course concerning conduction disturbances and associated pacemaker need. Whether using different guidewires might impact the outcome in challenging anatomies should be further investigated in randomized studies under standardized conditions

Effect of Chemical Mutagens and Carcinogens on Gene Expression Profiles in Human TK6 Cells

Characterization of toxicogenomic signatures of carcinogen exposure holds significant promise for mechanistic and predictive toxicology. In vitro transcriptomic studies allow the comparison of the response to chemicals with diverse mode of actions under controlled experimental conditions. We conducted an in vitro study in TK6 cells to characterize gene expression signatures of exposure to 15 genotoxic carcinogens frequently used in European industries. We also examined the dose-responsive changes in gene expression, and perturbation of biochemical pathways in response to these carcinogens. TK6 cells were exposed at 3 dose levels for 24 h with and without S9 human metabolic mix. Since S9 had an impact on gene expression (885 genes), we analyzed the gene expression data from cells cultures incubated with S9 and without S9 independently. The ribosome pathway was affected by all chemical-dose combinations. However in general, no similar gene expression was observed among carcinogens. Further, pathways, i.e. cell cycle, DNA repair mechanisms, RNA degradation, that were common within sets of chemical-dose combination were suggested by clustergram. Linear trends in dose–response of gene expression were observed for Trichloroethylene, Benz[a]anthracene, Epichlorohydrin, Benzene, and Hydroquinone. The significantly altered genes were involved in the regulation of (anti-) apoptosis, maintenance of cell survival, tumor necrosis factor-related pathways and immune response, in agreement with several other studies. Similarly in S9+ cultures, Benz[a]pyrene, Styrene and Trichloroethylene each modified over 1000 genes at high concentrations. Our findings expand our understanding of the transcriptomic response to genotoxic carcinogens, revealing the alteration of diverse sets of genes and pathways involved in cellular homeostasis and cell cycle control

Dose-dependent influence of genetic polymorphisms on DNA damage induced by styrene oxide, ethylene oxide and gamma-radiation.

Styrene oxide (SO), ethylene oxide (EO) and gamma-radiation (G) are agents with a well-described metabolism and genotoxicity. EPHX1 and GSTs play an important role in the detoxification of electrophiles and oxidative stress. Enzymes involved in base excision repair (hOGG1, XRCC1), in rejoining single strand breaks (XRCC1) and in repair of cross-links and chromosomal double strand breaks (XRCC3) might have an impact on genotoxicity as well. In this study we assessed the dose-dependent effect of genetic polymorphisms in biotransforming (EPHX (Tyr113/His113 and His139/Arg139), GSTP1 (Ile105/Val105), GSTM1 and GSTT1) and DNA repair enzymes (hOGG1 (Ser326/Cys326), XRCC1 (Arg194/Trp194, Arg280/His280, Arg399/Gln399), XRCC3 (Thr241/Met241)) on the induced genotoxicity. Peripheral blood mononuclear cells from 20 individuals were exposed to 3 doses per agent (+control). Genotoxicity was evaluated by measuring comet tail length (TL) and micronucleus frequencies in binucleated cells (MNCB). Dose-dependent DNA damage was found for all agents and end-points, with the exception of MNCB induced by EO. Repeated measure ANOVA revealed a significant contribution of hOGG1 and XRCC3 genotypes to the inter-individual variability of TL and MNCB in cells exposed to EO and G. Homozygous hOGG1326 wild cells showed significantly lower EO-induced TL than the heterozygous cells. Significantly higher TL and MNCB were found in EO-exposed cells carrying the XRCC3(241)Met variant and the influence on TL was more pronounced at higher dose. In G-irradiated cells, TL was significantly higher in the hOGG1326 homozygous wild types compared with mutated genotypes. The influence of hOGG1326 on TL was borderline dose-dependent. We conclude that the influence of genetic polymorphisms of enzymes involved in DNA repair on induced genotoxicity depends on exposure dose

Acquiring symptoms in response to odors: a learning perspective on multiple chemical sensitivity

In this chapter, a learning account is discussed as a potential explanation for the symptoms in multiple chemical sensitivity. Clinical evidence is scarce and anecdotal. A laboratory model provides more convincing results. After a few breathing trials containing CO2-enriched air as an unconditioned stimulus in a compound with harmless odor substances as conditioned stimuli, subjective symptoms are elicited and respiratory behavior is altered by the odors only. Also, mental images can become conditioned stimuli to trigger subjective symptoms. The learning effects cannot be explained by a response bias or by conditioned arousal, and they appear to involve basic associative processes that do not overlap with aware cognition of the relationship between the odors and the CO2 inhalation. Learned symptoms generalize to new odors and they can be eliminated in a Pavlovian extinction procedure. In accordance with clinical findings, neurotic subjects and psychiatric cases are more vulnerable to learning subjective symptoms in response to odors. Consistent with a learning account, cognitive-behavioral treatment techniques appear to produce beneficial results in clinical cases. Several criticisms and unresolved questions regarding the potential role of learning mechanisms are discussed.status: publishe

Influence of genetic polymorphisms on biomarkers of exposure and genotoxic effects in styrene-exposed workers.

A study on 44 workers exposed to styrene and 44 matched referents was performed in order to examine the influence of genetic polymorphisms in biotransformation and DNA repair enzymes on the levels of N-terminal hemoglobin adducts and genotoxicity biomarkers. Urinary mandelic acid concentration averaged 201.57 mg/g creatinine +/-148.32 in exposed workers, corresponding to a calculated average airborne styrene exposure of 9.5 ppm +/-9.6. Individuals with a high level of N-terminal valine adducts had higher levels of DNA damage, as evaluated by the Comet assay (r = 0.29, P = 0.008). Frequencies of micronucleated mononucleated lymphocytes (MNMC) (0.71 +/- 0.88 vs 0.11 +/- 0.20, P<0.0001), micronucleated binucleated lymphocytes (MNBC) (3.93 +/- 2.75 vs 2.65 +/- 1.94, p = 0.02) and micronucleated nasal epithelial cells (0.52 +/- 0.49 vs 0.23 +/- 0.31, p = 0.04) differed significantly between the exposed and referent groups. In the whole group of 88 individuals, higher frequencies of MNMC were found in individuals possessing the XRCC3 Met(241) allele and those individuals with the XRCC1 Gln( (399) ) allele showed higher frequencies of MNMC and MNCB. In vitro DNA repair capacity, as measured by residual DNA strand breaks in peripheral blood leukocytes after a styrene oxide challenge, was also influenced by styrene exposure, with an apparent induction of early repair mechanisms associated with the intensity of recent exposure and a reduction of late (24 h) repair capacity that was associated with the duration of employment. After 1 h of repair, lower levels of residual DNA damage were found in individuals possessing GSTT1 (P = 0.043). After 24 h of repair, lower residual DNA damage was found in individuals homozygous for XRCC1 Arg(194) (P = 0.013). Multivariate regression analysis indicated that the duration of exposure, smoking habits and polymorphisms of XRCC1 at codon 399 were important variables affecting the genotoxic responses. Our data suggest that DNA damage is formed in workers exposed to low concentrations of styrene, and that genotypes of metabolising and DNA-repair genes are important for the assessment of individual genotoxic risk to styrene. The in vitro DNA repair phenotype assay might be a valuable method to estimate the susceptibility of workers

Effect of chemical mutagens and carcinogens on gene expression profiles in human TK6 cells.

Characterization of toxicogenomic signatures of carcinogen exposure holds significant promise for mechanistic and predictive toxicology. In vitro transcriptomic studies allow the comparison of the response to chemicals with diverse mode of actions under controlled experimental conditions. We conducted an in vitro study in TK6 cells to characterize gene expression signatures of exposure to 15 genotoxic carcinogens frequently used in European industries. We also examined the dose-responsive changes in gene expression, and perturbation of biochemical pathways in response to these carcinogens. TK6 cells were exposed at 3 dose levels for 24 h with and without S9 human metabolic mix. Since S9 had an impact on gene expression (885 genes), we analyzed the gene expression data from cells cultures incubated with S9 and without S9 independently. The ribosome pathway was affected by all chemical-dose combinations. However in general, no similar gene expression was observed among carcinogens. Further, pathways, i.e. cell cycle, DNA repair mechanisms, RNA degradation, that were common within sets of chemical-dose combination were suggested by clustergram. Linear trends in dose-response of gene expression were observed for Trichloroethylene, Benz[a]anthracene, Epichlorohydrin, Benzene, and Hydroquinone. The significantly altered genes were involved in the regulation of (anti-) apoptosis, maintenance of cell survival, tumor necrosis factor-related pathways and immune response, in agreement with several other studies. Similarly in S9+ cultures, Benz[a]pyrene, Styrene and Trichloroethylene each modified over 1000 genes at high concentrations. Our findings expand our understanding of the transcriptomic response to genotoxic carcinogens, revealing the alteration of diverse sets of genes and pathways involved in cellular homeostasis and cell cycle control

Incidence, Risk Factors and Impact on Long-Term Outcome of Postoperative Delirium After Transcatheter Aortic Valve Replacement

Background: The aim of the present study was to analyze incidence, risk factors, and association with long-term outcome of postoperative delirium (POD) after transcatheter aortic valve replacement (TAVR). Methods: Six hundred and sixty one consecutive patients undergoing TAVR were prospectively enrolled from January 2016 to December 2017. POD was assessed regularly during ICU-stay using the CAM-ICU test. Results: The incidence of POD was 10.0% (n = 66). Patients developing POD were predominantly male (65%), had higher EuroSCORE II (5.4% vs. 3.9%; P = 0.041) and were more often considered frail (70% vs. 26%; P < 0.001). POD was associated with more peri-procedural complications including vascular complications (19.7 vs. 9.4; P = 0.017), bleeding (12.1 vs. 5.4%; P = 0.0495); stroke (4.5 vs. 0.7%; P = 0.025), respiratory failure requiring ventilation (16.7% vs. 1.8%; P < 0.001), and pneumonia (34.8% vs. 7.1%; P < 0.001). Consequently, patients with POD had significantly longer ICU- (7.9 vs. 3.2 days P < 0.001) and hospital-stay (14.9 vs. 9.0 days; P < 0.001), and higher in-hospital mortality (6.1 vs. 2.1%; P = 0.017). Logistic regression analysis identified male sex (odds ratio (OR) 2.2 [95% confidence interval (CI) 1.2-4.0); P = 0.012], atrial fibrillation [OR 3.0 (CI 1.6-5.6); P < 0.001], frailty [OR 4.3 (CI 2.4-7.9); P < 0.001], pneumonia [OR 4.4 (CI 2.3-8.7); P < 0.001], stroke [OR 7.0 (CI 1.2-41.6); P = 0.031], vascular complication [OR 2.9 (CI 1.3-6.3); P = 0.007], and general anesthesia [OR 2.0 (CI 1.0-3.7); P = 0.039] as independent predictors of POD. On Cox proportional hazard analysis POD emerged as a significant predictor of 2-year mortality [HR 1.89 (CI 1.06-3.36); P = 0.030]. Conclusion: POD is a frequent finding after TAVR and is significantly associated with reduced 2-year survival. Predictors of delirium include not only peri-procedural parameters like stroke, pneumonia, vascular complications and general anesthesia but also baseline characteristics as male sex, atrial fibrillation and frailty