Browsing by Subject "IMPLANTATION"

Sort by: Order: Results:

Now showing items 1-20 of 30
  • Zhang, Shuo; Pakarinen, Olli Heikki; Backholm, Matilda; Djurabekova, Flyura; Nordlund, Kai; Keinonen, Juhani; Wang, T.S. (2018)
    In this work, we first simulated the amorphization of crystalline quartz under 50 keV Na-23 ion irradiation with classical molecular dynamics (MD). We then used binary collision approximation algorithms to simulate the Rutherford backscattering spectrometry in channeling conditions (RBS-C) from these irradiated MD cells, and compared the RBS-C spectra with experiments. The simulated RBS-C results show an agreement with experiments in the evolution of amorphization as a function of dose, showing what appears to be (by this measure) full amorphization at about 2.2 eV.atom(-1). We also applied other analysis methods, such as angular structure factor, Wigner-Seitz, coordination analysis and topological analysis, to analyze the structural evolution of the irradiated MD cells. The results show that the atomic-level structure of the sample keeps evolving after the RBS signal has saturated, until the dose of about 5 eV.atom(-1). The continued evolution of the SiO2 structure makes the definition of what is, on the atomic level, an amorphized quartz ambiguous.
  • Moriyama, Noriaki; Laakso, Teemu; Raivio, Peter; Dahlbacka, Sebastian; Kinnunen, Eeva-Maija; Juvonen, Tatu; Valtola, Antti; Husso, Annastiina; Jalava, Maina P.; Ahvenvaara, Tuomas; Tauriainen, Tuomas; Piuhola, Jarkko; Lahtinen, Asta; Niemelä, Matti; Mäkikallio, Timo; Virtanen, Marko; Maaranen, Pasi; Eskola, Markku; Savontaus, Mikko; Airaksinen, Juhani; Biancari, Fausto; Laine, Mika (2021)
    Background: The 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. Methods: This registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate Results: The 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. Conclusions: TAVR 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.
  • Maaranen, Pasi; Husso, Annastiina; Tauriainen, Tuomas; Lahtinen, Asta; Valtola, Antti; Ahvenvaara, Tuomas; Virtanen, Marko; Laakso, Teemu; Kinnunen, Eeva-Maija; Dahlbacka, Sebastian; Juvonen, Tatu; Mäkikallio, Timo; Jalava, Maina P.; Jaakkola, Jussi; Airaksinen, Juhani; Vasankari, Tuija; Rosato, Stefano; Savontaus, Mikko; Laine, Mika; Raivio, Peter; Niemelä, Matti; Mennander, Ari; Eskola, Markku; Biancari, Fausto (2019)
    Objective: To investigate the prognostic impact of red blood cell (RBC) transfusion on the outcome after transfemoral transcatheter aortic valve replacement (TAVR). Design: Nationwide, retrospective multicenter study. Setting: Five University Hospitals. Participants: The nationwide FinnValve registry included data from 2,130 patients who underwent TAVR for aortic stenosis from 2008 to 2017. After excluding patients who underwent TAVR through nontransfemoral accesses, 1,818 patients were selected for this analysis. Intervention: TAVR with or without coronary revascularization. Measurements and Main Results: RBCs were transfused in 293 patients (16.1%). Time-trend analysis showed that the rates of RBC transfusion decreased significantly from 27.5% in 2012 to 10.0% in 2017 (p <0.0001). Among 281 propensity score matched pairs, RBC transfusion was associated with higher 30-day mortality (7.1% v 0%, p <0.0001), late mortality (at 5-year, 59.1% v 43.3%, p = 0.008), as well as increased risk of acute kidney injury (17.0% v 4.4%, p <0.0001), renal replacement therapy (3.6% v 0.4, p <0.0001) and prolonged hospital stay (mean, 8.5 v 4.7 days, p <0.0001) compared with patients who did not receive blood transfusion. In the overall series, the risk of adverse events increased significantly with the increasing amount of transfused RBC units and when operation for excessive bleeding was necessary. Consistently with these findings, postoperative hemoglobin drop and nadir level were associated with higher early and late mortality. Conclusions: Patients who received blood transfusion after TAVR had an increased risk of early and late adverse events. These adverse effects were particularly evident with increasing amount of RBC transfusion and operations for excessive bleeding. (C) 2019 Elsevier Inc. All rights reserved.
  • Pätilä , Tommi; Miyagawa, Shigeru; Imanishi, Yukiko; Fukushima, Satsuki; Siltanen, Antti; Mervaala, Eero; Kankuri, Esko; Harjula, Ari; Sawa, Yoshiki (2015)
    Although cell therapy of the failing heart by intramyocardial injections of myoblasts to results in regenerative benefit, it has also been associated with undesired and prospectively fatal arrhythmias. We hypothesized that intramyocardial injections of myoblasts could enhance inflammatory reactivity and facilitate electrical cardiac abnormalities that can be reduced by epicardial myoblast sheet delivery. In a rat model of ischemic heart failure, myoblast therapy either by intramyocardial injections or epicardial cell sheets was given 2 weeks after occlusion of the coronary artery. Ventricular premature contractions (VPCs) were assessed, using an implanted three-lead electrocardiograph at 1, 7, and 14 days after therapy, and 16-point epicardial electropotential mapping (EEPM) was used to evaluate ventricular arrhythmogenicity under isoproterenol stress. Cardiac functioning was assessed by echocardiography. Both transplantation groups showed therapeutic benefit over sham therapy. However, VPCs were more frequent in the Injection group on day 1 and day 14 after therapy than in animals receiving epicardial or sham therapy (p <0.05 and p <0.01, respectively). EEPM under isoproterenol stress showed macroreentry at the infarct border area, leading to ventricular tachycardias in the Injection group, but not in the myoblast sheet- or sham-treated groups (p = 0.045). Both transplantation types modified the myocardial cytokine expression profile. In animals receiving epicardial myoblast therapy, selective reductions in the expressions of interferon gamma, interleukin (IL)-1 beta and IL12 were observed, accompanied by reduced infiltration of inflammatory CD11b- and CD68-positive leukocytes, compared with animals receiving myoblasts as intramyocardial injections. Intramyocardial myoblast delivery was associated with enhanced inflammatory and immunomodulatory reactivity and increased frequency of VPCs. In comparison to intramyocardial injection, the epicardial route may serve as the preferred method of skeletal myoblast transplantation to treat heart failure.
  • Boggavarapu, Nageswara Rao; Lalitkumar, Sujata; Joshua, Vijay; Kasvandik, Sergo; Salumets, Andres; Lalitkumar, Parameswaran Grace; Gemzell-Danielsson, Kristina (2016)
    The complexity of endometrial receptivity at the molecular level needs to be explored in detail to improve the management of infertility. Here, differential expression of transcriptomes in receptive endometrial glands and stroma revealed Ectonucleotide Pyrophosphatase/Phosphodiesterase 3 (ENPP3) as a progesterone regulated factor and confirmed by various methods, both at mRNA and protein level. The involvement of ENPP3 in embryo attachment was tested in an in vitro model for human embryo implantation. Interestingly, there was high expression of ENPP3 mRNA in stroma but not protein. Presence of N-glycosylated ENPP3 in receptive phase uterine fluid in women confirms its regulation by progesterone and makes it possible to use in a non-invasive test of endometrial receptivity.
  • Jahnukainen, Timo; Lauronen, Jouni; Raissadati, Alireza; Pihkala, Jaana I.; Ylinen, Elisa; Puntila, Juha Tapani; Salminen, Jukka T.; Pätilä, Tommi; Mattila, Ilkka P.; Jalanko, Hannu Jaakko (2019)
    Background: The appearance of human leukocyte antigen (HLA) antibodies after solid organ transplantation predisposes recipients to graft dysfunction. In theory, vascular homografts, which are widely used in children with congenital heart defects, may cause allosensitization. Material/Methods: In this single-center retrospective study, the presence of pre-existing HLA antibodies in pediatric heart trans- plant (HTx) recipients with a vascular homograft was evaluated in a cohort of 12 patients. HLA antibodies were screened before and after HTx and positive screening results were confirmed and identified using the Luminex (R) single antigen bead method. Endomyocardial biopsies (EMB) and coronary angiography studies were re-evaluated to assess the prevalence of acute rejections and coronary artery change in these patients. Results: At the time of HTx, 8 patients (67%) had HLA antibodies detected by the Luminex assay, none of which were heart donor specific (DSA). All patients had negative leukocyte crossmatch. One patient developed DSAs against homograft donor prior to HTx. After the HTx, 5 patients (42%) developed DSAs against the heart donor and 4 patients (40%) against the homograft donor. In 2 patients (17%), the antibodies were against both heart and homograft donors. The rejection rate or prevalence of coronary artery vasculopathy did not differ significantly between the homograft cohort and our historical controls. Conclusions: Our results suggest that the prevalence of DSAs against homograft donor prior to HTx is relatively rare. However, almost half of the patients developed DSAs against homograft post-HTx. The clinical importance of these antibodies warrants further studies.
  • Kukushkina, Viktorija; Modhukur, Vijayachitra; Suhorutsenko, Marina; Peters, Maire; Magi, Reedik; Rahmioglu, Nilufer; Velthut-Meikas, Agne; Altmae, Signe; Esteban, Francisco J.; Vilo, Jaak; Zondervan, Krina; Salumets, Andres; Laisk-Podar, Triin (2017)
    The inner uterine lining (endometrium) is a unique tissue going through remarkable changes each menstrual cycle. Endometrium has its characteristic DNA methylation profile, although not much is known about the endometrial methylome changes throughout the menstrual cycle. The impact of methylome changes on gene expression and thereby on the function of the tissue, including establishing receptivity to implanting embryo, is also unclear. Therefore, this study used genome-wide technologies to characterize the methylome and the correlation between DNA methylation and gene expression in endometrial biopsies collected from 17 healthy fertile-aged women from pre-receptive and receptive phase within one menstrual cycle. Our study showed that the overall methylome remains relatively stable during this stage of the menstrual cycle, with small-scale changes affecting 5% of the studied CpG sites (22,272 out of studied 437,022 CpGs, FDR <0.05). Of differentially methylated CpG sites with the largest absolute changes in methylation level, approximately 30% correlated with gene expression measured by RNA sequencing, with negative correlations being more common in 5 ' UTR and positive correlations in the gene 'Body' region. According to our results, extracellular matrix organization and immune response are the pathways most affected by methylation changes during the transition from pre-receptive to receptive phase.
  • Burwick, Richard M.; Lokki, A. Inkeri; Fleming, Sherry D.; Regal, Jean F. (2021)
  • Blackman, Daniel; Gabbieri, Davide; Del Blanco, Bruno Garcia; Kempfert, Jorg; Laine, Mika; Mascherbauer, Julia; Parma, Radoslaw; Tchetche, Didier (2021)
    Severe aortic stenosis patients with bicuspid anatomy have been excluded from the major transcatheter aortic valve replacement (TAVI) randomized clinical trials. As a result, there is no official recommendation on bicuspid TAVI. A panel of bicuspid experts was created to fill this gap. In this consensus statement, an algorithm is proposed to guide the choice of surgery or TAVI within this complex patient population, depending on aortic dilatation, age, surgical risk score, and anatomy. A step-by-step guide for sizing and positioning of the SAPIEN 3/Ultra TAVI bioprostheses is presented. Annular sizing remains the primary strategy in most bicuspid patients. However, some anatomies may require sizing at the supra-annular level, for which patients the panel recommends the circle method, a dedicated sizing and positioning approach for SAPIEN 3/Ultra. The consensus provides valuable pre-operative insights on the interactions between SAPIEN 3/Ultra and the bicuspid anatomy; understanding the valve-anatomy relationship is critical to avoid complications and to optimize outcomes for patients.
  • Biancari, Fausto; Dahlbacka, Sebastian; Juvonen, Tatu; Virtanen, Marko P.O.; Maaranen, Pasi; Jaakkola, Jussi; Laakso, Teemu; Niemelä, Matti; Tauriainen, Tuomas; Vento, Antti; Husso, Annastiina; Savontaus, Mikko; Laine, Mika; Mäkikallio, Timo; Raivio, Peter; Eskola, Markku; Rosato, Stefano; Anttila, Vesa; Airaksinen, Juhani; Valtola, Antti (2020)
    Aim The aim of this study was to assess the outcome of transcatheter aortic valve replacement (TAVR) in patients with cancer. Methods This is a retrospective study from the nationwide FinnValve registry on 2130 consecutive patients who underwent TAVR for severe AS from January 2008 to October 2017. Results In this cohort, 417 patients (19.6%) had history of cancer and 113 (5.3%) had an active malignancy at the time of TAVR. Patients with any malignancy had similar late mortality than patients without any malignancy (at 7 years, 65.1% vs. 59.3%, adjusted HR 1.105, 95%CI 0.892–1.369). At 7 years, cancer-related mortality was 22.5% among patients with preoperative cancer, and 11.0% in those without preoperative cancer (p 
  • Sand, Andrea E.; Ullah, Rafi; Correa, Alfredo A. (2019)
    The effects of incident energetic particles, and the modification of materials under irradiation, are governed by the mechanisms of energy losses of ions in matter. The complex processes affecting projectiles spanning many orders of magnitude in energy depend on both ion and electron interactions. Developing multi-scale modeling methods that correctly capture the relevant processes is crucial for predicting radiation effects in diverse conditions. In this work, we obtain channeling ion ranges for tungsten, a prototypical heavy ion, by explicitly simulating ion trajectories with a method that takes into account both the nuclear and the electronic stopping power. The electronic stopping power of self-ion irradiated tungsten is obtained from first-principles time-dependent density functional theory (TDDFT). Although the TDDFT calculations predict a lower stopping power than SRIM by a factor of three, our result shows very good agreement in a direct comparison with ion range experiments. These results demonstrate the validity of the TDDFT method for determining electronic energy losses of heavy projectiles, and in turn its viability for the study of radiation damage.
  • Saia, Francesco; Gandolfo, Caterina; Palmerini, Tullio; Berti, Sergio; Doshi, Sagar N.; Laine, Mika; Marcelli, Chiara; Piva, Tommaso; Ribichini, Flavio; De Benedictis, Mauro; Cardaioli, Francesco; Cannata, Stefano; Tarantini, Giuseppe (2020)
    Aims: The aim of this study was to evaluate 30-day safety and efficacy outcomes of transcatheter aortic valve implantation (TAVI) performed with the SAPIEN 3 Ultra system. Methods and results: The S3U registry is a physician-led, post-approval, multicentre, observational registry of transfemoral TAVI with the SAPIEN 3 Ultra. New features include an improved sealing skirt, a 14 Fr expandable sheath and a new delivery catheter. Overall, 139 consecutive patients at nine participating centres were enrolled. Mean age was 81.4 +/- 8.3 years, average STS score 3.8 +/- 2.4%. The vast majority (97.2%) underwent TAVI with local anaesthesia (28.8%) or conscious sedation (68.3%). Balloon predilatation was performed in 30 patients (21.6%), post-dilatation in three (2.2%). In-hospital, there were no cases of death, stroke, or conversion to open heart surgery. Major vascular complications occurred in three patients (2.2%), as well as major or life-threatening bleedings in three patients (2.2%). There were two moderate (1.4%) and no moderate/severe paravalvular leaks. Median length of stay after TAVI was three days (IQR 3-5 days). At 30 days, there were no deaths, MI, or strokes, and the incidence of new permanent pacemaker implantation was 4.4%. Conclusions: This first multicentre international experience of transfemoral TAVI with the SAPIEN 3 Ultra transcatheter heart valve shows good in-hospital and 30-day clinical outcomes.
  • Lindholm, Juha-Matti; Laine, Ilkka; Tuuminen, Raimo (2020)
    The present study estimated the 5-year cumulative probability of Nd:YAG laser posterior capsulotomy according to the diopter power of implanted hydrophobic acrylic intraocular lenses (IOLs). Data were retrospectively collected of 15,375 eyes having cataract surgery and in-the-bag implantation of hydrophobic acrylic monofocal IOLs at the Ophthalmology Unit of Kymenlaakso Central Hospital, Kotka, Finland between the years 2007 and 2016. The cumulative probability of Nd:YAG capsulotomy was calculated by Kaplan-Meier estimates, and potential risk factors were analyzed using the Cox proportional hazards model. The 5-year cumulative probability of Nd:YAG capsulotomy after cataract surgery was 27.4% (95% confidence interval (CI) 22.9-32.6%) for low-diopter (5-16.5 D) IOLs, 14.6% (13.8-15.5%) for mid-diopter (17-24.5 D) IOLs, and 13.6% (11.7-15.6%) for high-diopter (25-30 D) IOLs. A multivariate Cox regression analysis showed that low-diopter IOLs (HR 1.76; 95% CI 1.38-2.25; p <0.001) were associated with an increased risk of Nd:YAG capsulotomy compared to mid-diopter IOLs over the follow-up period after accounting for other predictors. Real-world evidence shows that low-diopter IOLs are associated with significantly higher risk of Nd:YAG capsulotomy within five years following implantation. Estimation should help in evaluating the risks of cataract surgery in myopic eyes.
  • Nammas, Wail; de Belder, Adam; Niemela, Matti; Sia, Jussi; Romppanen, Hannu; Laine , Mika; Karjalainen, Pasi P. (2017)
    Background: The BASE ACS trial demonstrated an outcome of titanium-nitride-oxide-coated bioactive stents (BAS) that was non-inferior to everolimus-eluting stents (EES) in patients presenting with acute coronary syndrome (ACS). We performed a post hoc analysis of elderly versus non-elderly patients from the BASE ACS trial. Methods: We randomized 827 patients (1:1) presenting with ACS to receive either BAS or EES. The primary end-point was major adverse cardiac events (MACE): a composite of cardiac death, non-fatal myocardial infarction (MI), or ischemia-driven target lesion revascularization (TLR). Follow-up was planned at 12 months and yearly thereafter for up to 7 years. Elderly age was defined as >= 65 years. Results: Of the 827 patients enrolled in the BASE ACS trial, 360 (43.5%) were elderly. Mean follow-up duration was 4.2 +/- 1.9 years. MACE was more frequent in elderly versus younger patients (19.7% versus 12.0%, respectively, p = 0.002), probably driven by more frequent cardiac death and non-fatal MI events (5.3% versus 1.5%, and 9.7% versus 4.5%, p = 0.002 and p = 0.003, respectively). The rates of ischemia-driven TLR were comparable (p > 0.05). In propensity score-matched analysis (215 pairs), only cardiac death was more frequent in elderly patients (6% versus 1.4%, respectively, p = 0.01). Diabetes independently predicted both MACE and cardiac death in elderly patients. Conclusions: Elderly patients treated with stent implantation for ACS had worse long-term clinical outcome, compared with younger ones, mainly due to a higher death rate. (C) 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.
  • Ilveskoski, Lotta; Taipale, Claudia; Holmstrom, Emil J.; Tuuminen, Raimo (2019)
    Background: The purpose of the study was to identify macular edema after cataract surgery in eyes with and without pseudoexfoliation syndrome. The study was a post-hoc analysis of a randomized, double-blind, prospective single-center study. Patients were enrolled between January 2016 and October 2016 as per the national guidelines for the management of cataract in the Department of Ophthalmology, Kymenlaakso Central Hospital, Kotka, Finland. Methods: One hundred and fifty-six eyes of 149 patients undergoing routine cataract surgery. Postoperatively anti-inflammatory medication was either dexamethasone (N = 78) or diclofenac (N = 78). Spectral domain optical coherence tomography imaging and laser flare meter measurement of the anterior chamber were conducted before surgery and at the control visit 28 days postoperatively. Results: Baseline variables were comparable between eyes with pseudoexfoliation syndrome (N = 32) and those without (N = 124), except for intraocular pressure (P = 0.002) and glaucoma medication (P <0.001). In patients having pseudoexfoliation syndrome, central retinal thickness increase (mean +/- standard error of the mean) was 63.3 +/- 35.5 mu m for dexamethasone and 17.6 +/- 5.8 mu m for diclofenac, compared to 28.9 +/- 8.0 mu m (P = NS) and 6.9 +/- 1.3 mu m (P = 0.014) in eyes without pseudoexfoliation syndrome, respectively. Aqueous flare at 28 days was 25.8 +/- 5.4 pu/ms for patients with pseudoexfoliation syndrome and 18.3 +/- 1.8 pu/ms for those without (P = 0.030). Best corrected visual acuity gain and best corrected visual acuity at 28 days were less in patients having pseudoexfoliation syndrome compared to those without (0.39 +/- 0.07 vs 0.59 +/- 0.03 decimals, P = 0.007; and 0.77 +/- 0.06 vs 0.92 +/- 0.03 decimals, P = 0.008, respectively). Conclusion: Eyes with pseudoexfoliation syndrome may be predisposed to an increased aqueous flare and macular edema after cataract surgery. This study outlines the need to determine the optimal anti-inflammatory medication after cataract surgery in patients with pseudoexfoliation syndrome.
  • Virtanen, Marko P. O.; Eskola, Markku; Savontaus, Mikko; Juvonen, Tatu; Niemelä, Matti; Laakso, Teemu; Husso, Annastiina; Jalava, Maina P.; Tauriainen, Tuomas; Ahvenvaara, Tuomas; Maaranen, Pasi; Kinnunen, Eeva-Maija; Dahlbacka, Sebastian; Laine, Mika; Mäkikallio, Timo; Valtola, Antti; Raivio, Peter; Rosato, Stefano; D'Errigo, Paola; Vento, Antti; Airaksinen, Juhani; Biancari, Fausto (2020)
    BackgroundThere is limited information on the longer-term outcome after transcatheter aortic valve replacement (TAVR) with new-generation prostheses compared to surgical aortic valve replacement (SAVR). The aim of this study was to compare the mid-term outcomes after TAVR with Sapien 3 and SAVR with Perimount Magna Ease bioprostheses for severe aortic stenosis.MethodsIn a retrospective study, we included patients who underwent transfemoral TAVR with Sapien 3 or SAVR with Perimount Magna Ease bioprosthesis between January 2008 and October 2017 from the nationwide FinnValve registry. Propensity score matching was performed to adjust for differences in the baseline characteristics. The Kaplan-Meir method was used to estimate late mortality.ResultsA total of 2000 patients were included (689 in the TAVR cohort and 1311 in the SAVR cohort). Propensity score matching resulted in 308 pairs (STS score, TAVR 3.52.2% vs. SAVR 3.52.8%, p=0.918). In-hospital mortality was 3.6% after SAVR and 1.3% after TAVR (p=0.092). Stroke, acute kidney injury, bleeding and atrial fibrillation were significantly more frequent after SAVR, but higher rate of vascular complications was observed after TAVR. The cumulative incidence of permanent pacemaker implantation at 4years was 13.9% in the TAVR group and 6.9% in the SAVR group (p=0.0004). At 4-years, all-cause mortality was 20.6% for SAVR and 25.9% for TAVR (p=0.910). Four-year rates of coronary revascularization, prosthetic valve endocarditis and repeat aortic valve intervention were similar between matched cohorts.Conclusions p id=Par The Sapien 3 bioprosthesis achieves comparable midterm outcomes to a surgical bioprosthesis with proven durability such as the Perimount Magna Ease. However, the Sapien 3 bioprosthesis was associated with better early outcome.Trial registration p id=Par Identifier: NCT03385915.
  • Hodille, E. A.; Byggmästar, J.; Safi, E.; Nordlund, K. (2019)
    The sputtering and reflection properties of wurtzite beryllium oxide (BeO) subjected to deuterium (D) ions bombardment at 300 K with ion energy between 10 eV and 200 eV is studied by classical molecular dynamics. Cumulative irradiations of wurtzite BeO show a D concentration threshold above which an 'unphysical dramatic' sputtering is observed. From the cumulative irradiations, simulation cells with different D concentrations are used to run non-cumulative irradiations at different concentrations. Using a D concentration close to the experimentally determined saturation concentration (0.12 atomic fraction), the simulations are able to reproduce accurately the experimental sputtering yield of BeO materials. The processes driving the sputtering of beryllium (Be) and oxygen (O) atoms as molecules are subsequently determined. At low irradiation energy, between 10 eV and 80 eV, swift chemical sputtering (SCS) is dominant and produces mostly ODz molecules. At high energy, the sputtered molecules are mostly BexOy molecules (mainly BeO dimer). Four different processes are associated to the formation of such molecules: the physical sputtering of BeO dimer, the delayed SCS not involving D ions and the detachment-induced sputtering. The physical sputtering of BeO dimer can be delayed if the sputtering event implies two interactions with the incoming ion (first interaction in its way in the material, the other in its way out if it is backscattered). The detachment-induced sputtering is a characteristic feature of the 'dramatic' sputtering and is mainly observed when the concentration of D is close to the threshold leading to this sputtering regime.
  • Stepanjuk, Artjom; Koel, Mariann; Pook, Martin; Saare, Merli; Jääger, Kersti; Peters, Maire; Krjutskov, Kaarel; Ingerpuu, Sulev; Salumets, Andres (2019)
    Research question: How does mucin MUC20 expression change during the menstrual cycle in different cell types of human endometrium? Design: Study involved examination of MUC20 expression in two previously published RNA-seq datasets in whole endometrial tissue (n = 10), sorted endometrial epithelial (n = 44) or stromal (n = 42) cell samples. RNA-Seq results were validated by quantitative reverse transcription polymerase chain reaction (qRT-PCR) in whole tissue (n = 10), sorted epithelial (n = 17) and stromal (n = 17) cell samples. MUC20 protein localization and expression were analysed in human endometrium by immunohistochemical analysis of intact endometrial tissue (n = 6) and also Western blot of cultured stromal and epithelial cells (n = 2). Results: MUC20 is differentially expressed in the endometrium between the pre-receptive and receptive phases. We show that MUC20 is predominantly expressed by epithelial cells of the receptive endometrium, both at the mRNA (RNA-Seq, P = 0.005; qRT-PCR, P = 0.039) and protein levels (Western blot; immunohistochemistry, P = 0.029). Conclusion: Our results indicate MUC20 as a novel marker of mid-secretory endometrial biology. We propose a model of MUC20 function in the hepatocyte growth factor (HGF)-activated mesenchymal-epithelial transition (MET) receptor signalling specifically in the receptive phase. Further investigations should reveal the precise function of MUC20 in human endometrium and the possible connection between MUC20 and HGF-activated MET receptor signalling. MUC20 could potentially be included in the list of endometrial receptivity markers after further clinical validation.
  • Khatun, Masuma; Sorjamaa, Anna; Kangasniemi, Marika; Sutinen, Meeri; Saio, Tuuia; Liakka, Annikki; Lehenkari, Petri; Tapanainen, Juha S.; Vuolteenaho, Olli; Chen, Joseph C.; Lehtonen, Siri; Piltonen, Terhi T. (2017)
    Objective Intrinsic inflammatory characteristics play a pivotal role in stem cell recruitment and homing through migration where the subsequent change in niche has been shown to alter these characteristics. The bone marrow mesenchymal stem cells (bmMSCs) have been demonstrated to migrate to the endometrium contributing to the stem cell reservoir and regeneration of endometrial tissue. Thus, the aim of the present study was to compare the inflammation-driven migration and cytokine secretion profile of human bmMSCs to endometrial mesenchymal stem cells (eMSCs) and endometrial fibroblasts (eSFs). Materials and methods The bmMSCs were isolated from bone marrow aspirates through culturing, whereas eMSCs and eSFs were FACS-isolated. All cell types were tested for their surface marker, proliferation profiles and migration properties towards serum and inflammatory attractants. The cytokine/chemokine secretion profile of 35 targets was analysed in each cell type at basal level along with lipopolysaccharide (LPS)-induced state. Results Both stem cell types, bmMSCs and eMSCs, presented with similar stem cell surface marker profiles as well as possessed high proliferation and migration potential compared to eSFs. In multiplex assays, the secretion of 16 cytokine targets was detected and LPS stimulation expanded the cytokine secretion pattern by triggering the secretion of several targets. The bmMSCs exhibited higher cytokine secretion of vascular endothelial growth factor (VEGF)A, stromal cell-derived factor-1 alpha (SDF)-1 alpha, interleukin-1 receptor antagonist (IL-1RA), IL-6, interferon-gamma inducible protein (IP)-10, monocyte chemoattractant protein (MCP)1, macrophage inflammatory protein (MIP) 1 alpha and RANTES compared to eMSCs and/or eSFs after stimulation with LPS. The basal IL-8 secretion was higher in both endometrial cell types compared to bmMSCs. Conclusion Our results highlight that similar to bmMSCs, the eMSCs possess high migration activity while the differentiation process towards stromal fibroblasts seemed to result in loss of stem cell surface markers, minimal migration activity and a subtler cytokine profile likely contributing to normal endometrial function