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1.
Sci Rep ; 12(1): 22060, 2022 Dec 21.
Article in English | MEDLINE | ID: mdl-36543839

ABSTRACT

We studied the structural, chemical, and magnetic properties of Ti/Au/Co/Ni layered systems subjected to plasma oxidation. The process results in the formation of NiO at the expense of metallic Ni, as clearly evidenced by X-ray photoelectron spectroscopy, while not affecting the surface roughness and grain size of the Co/Ni bilayers. Since the decrease of the thickness of the Ni layer and the formation of NiO increase the perpendicular magnetic anisotropy, oxidation may be locally applied for magnetic patterning. Using this approach, we created 2D heterostructures characterized by different combinations of magnetic properties in areas modified by plasma oxidation and in the regions protected from oxidation. As plasma oxidation is an easy to use, low cost, and commonly utilized technique in industrial applications, it may constitute an improvement over other magnetic patterning methods.

2.
Sensors (Basel) ; 22(22)2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36433447

ABSTRACT

This paper presents a new approach to the structural integration of piezoceramics into thin-walled steel components for condition-monitoring applications. The procedure for integrating the sensors into metal components is described, and their functionality is experimentally examined with a 2 mm-thick steel sheet. The signal quality of the produced sensors is investigated in a frequency range from 100 Hz to 50,000 Hz and is compared with the results of piezo patches and strain gauges under the same conditions. The results show that due to a higher signal-to-noise ratio and a better coherence, the structurally integrated piezoceramics and the piezo patches are more qualified sensors for vibration measurement in the examined frequency range than the strain gauges. The measurements also indicate that the patches provide higher amplitudes for the frequency range up to 20 kHz. Beyond that, up to 40 kHz, the integrated sensors supplied higher amplitudes. The better signal quality in different frequency ranges as well as the different manufacturing and application methods can be interpreted as an advantage or disadvantage depending on the boundary conditions of the condition-monitoring system. In summary, structural integrated piezoceramics extend the options of monitoring technology.

3.
Materials (Basel) ; 14(5)2021 Mar 05.
Article in English | MEDLINE | ID: mdl-33807937

ABSTRACT

The ability to induce and control the perpendicular magnetic anisotropy (PMA) of ferromagnetic layers has been widely investigated, especially those that offer additional functionalities (e.g., skyrmion stabilization, voltage-based magnetization switching, rapid propagation of domain walls). Out-of-plane magnetized ferromagnetic layers in direct contact with an oxide belong to this class. Nowadays, investigation of this type of system includes antiferromagnetic oxides (AFOs) because of their potential for new approaches to applied spintronics that exploit the exchange bias (EB) coupling between the ferromagnetic and the AFO layer. Here, we investigate PMA and EB effect in NiO/Co/Au and NiO/Co/NiO layered systems. We show that the coercive and EB fields increase significantly when the Co layer is coupled with two NiO layers, instead of one. Surrounding the Co layer only with NiO layers induces a strong PMA resulting in an out-of-plane magnetized system can be obtained without a heavy metal/ferromagnetic interface. The PMA arises from a significant surface contribution (0.74 mJ/m2) that can be enhanced up to 0.99 mJ/m2 by annealing at moderate temperatures (~450 K). Using field cooling processes for both systems, we demonstrate a wide-ranging control of the exchange bias field without perturbing other magnetic properties of importance.

4.
Materials (Basel) ; 14(6)2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33802017

ABSTRACT

The current article proposes a concept for the additive manufacturing of rubber components using extrusion-based 3D printing, in which an additional medium is added to ensure the maintenance of shape within the elastomeric structure during the additive manufacturing process and in the subsequent vulcanization process. Specific requirements for the dimensional stabilization of the media were defined and suitable media were derived. Silicone rubber, molding sand, and plaster were examined in experimental vulcanization tests for their suitability as possible media with regard to shape retention. Selected rubber geometries made of NBR were embedded in these media to undergo the vulcanization process. The results show a significant influence of the media on the heating times. All media were able to ensure that the rubber geometries maintained their shape during vulcanization. Nevertheless, some side effects were found. The silicone rubber did not cure properly around the rubber sample. Therefore, it was difficult to remove it from the rubber after vulcanization. The molding sand caused an increased surface roughness on the rubber. Plaster changed the glossy surfaces at the beginning to a matte one after vulcanization and residuals were difficult to remove. However, all media can serve as stabilization media with specific changes.

5.
Article in English | MEDLINE | ID: mdl-33612835

ABSTRACT

BACKGROUND AND AIM: Placental Growth Factor (PlGF) plays a crucial role in angiogenesis and was identified as a potential prognostic biomarker in various types of cancer. Therefore, we evaluated the diagnostic accuracy and prognostic value of PlGF serum concentration in patients with clear cell renal cell carcinoma (ccRCC). PATIENTS AND METHODS: A total of 49 patients subjected to partial or radical nephrectomy for ccRCC [localized without relapse (lccRCC; n=31), localized with later relapse (rccRCC; n=8), primary metastatic cancer (mccRCC; n=10); median of follow-up 4.4 years] were enrolled in a prospective study to assess the significance of PlGF serum concentration. PlGF was measured prior to surgery and 3 months postoperatively. Our control group consisted of 38 healthy subjects. RESULTS: PlGF serum concentration was significantly higher in ccRCC compared to controls (P=0.002). The cut-off value of PlGF concentration for the risk of ccRCC was determined at 12.71 pg/mL (AUC=0.729; P=0.0001). Prior to surgery, among ccRCC subgroups, significantly higher PlGF concentration was detected in mccRCC compared to lccRCC (P=0.002). Postoperatively, we observed a tendency to higher PlGF serum concentration in rccRCC compared to lccRCC subgroup, however without significance (P=0.17). The cut-off value for the risk of relapse was 11.41 pg/mL (AUC=0.792; P=0.0003). In subjects with localized ccRCC with PlGF concentration below 11.41 pg/mL 3-years cancer specific survival was 93% compared to 61% in subject with concentration above the cut-off value (P=0.018). CONCLUSION: Based on our findings, PlGF serum concentration seems to be a useful biomarker in diagnostics and prediction of prognosis in ccRCC.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Biomarkers , Carcinoma, Renal Cell/diagnosis , Female , Humans , Neoplasm Recurrence, Local/diagnosis , Placenta Growth Factor , Prognosis , Prospective Studies
6.
Sci Rep ; 11(1): 1041, 2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33441724

ABSTRACT

Recent results showed that the ferrimagnetic compensation point and other characteristic features of Tb/Co ferrimagnetic multilayers can be tailored by He+ ion bombardment. With appropriate choices of the He+ ion dose, we prepared two types of lattices composed of squares with either Tb or Co domination. The magnetization reversal of the first lattice is similar to that seen in ferromagnetic heterostructures consisting of areas with different switching fields. However, in the second lattice, the creation of domains without accompanying domain walls is possible. These domain patterns are particularly stable because they simultaneously lower the demagnetizing energy and the energy associated with the presence of domain walls (exchange and anisotropy). For both lattices, studies of magnetization reversal show that this process takes place by the propagation of the domain walls. If they are not present at the onset, the reversal starts from the nucleation of reversed domains and it is followed by domain wall propagation. The magnetization reversal process does not depend significantly on the relative sign of the effective magnetization in areas separated by domain walls.

7.
Polymers (Basel) ; 12(10)2020 Oct 01.
Article in English | MEDLINE | ID: mdl-33019723

ABSTRACT

The dissemination and use of additive processes are growing rapidly. Nevertheless, for the material class of elastomers made of vulcanizable rubber, there is still no technical solution for producing them using 3D printing. Therefore, this paper deals with the basic investigations to develop an approach for rubber printing. For this purpose, a fused deposition modeling (FDM) 3D printer is modified with a screw extruder. Tests are carried out to identify the optimal printing parameters. Afterwards, test prints are performed for the deposition of rubber strands on top of each other and for the fabrication of simple two-dimensional geometries. The material behavior during printing, the printing quality as well as occurrences of deviations in the geometries are evaluated. The results show that the realization of 3D rubber printing is possible. However, there is still a need for research to stabilize the layers during the printing process. Additionally, further studies are necessary to determine the optimum parameters for traverse speed and material discharge, especially on contours.

8.
Micromachines (Basel) ; 11(4)2020 Apr 07.
Article in English | MEDLINE | ID: mdl-32272618

ABSTRACT

This paper demonstrates that the electrical properties of suspended graphene nanomesh (GNM) can be tuned by systematically changing the porosity with helium ion beam milling (HIBM). The porosity of the GNM is well-controlled by defining the pitch of the periodic nanopores. The defective region surrounding the individual nanopores after HIBM, which limits the minimum pitch achievable between nanopores for a certain dose, is investigated and reported. The exponential relationship between the thermal activation energy (EA) and the porosity is found in the GNM devices. Good EA tuneability observed from the GNMs provides a new approach to the transport gap engineering beyond the conventional nanoribbon method.

9.
Eur Urol Focus ; 6(6): 1190-1194, 2020 11 15.
Article in English | MEDLINE | ID: mdl-30661943

ABSTRACT

BACKGROUND: The European School of Urology (ESU) and EAU Section of Uro-Technology (ESUT) started hands-on-training (HOT) sessions in 2007 along with structured European Basic Laparoscopic Urological Skills (EBLUS) examinations in 2013. EBLUS includes an online theoretical course, HOT by expert tutors on a set of dry-lab exercises, and finally a standardised examination for skill assessment and certification. OBJECTIVE: To analyse the results and predictors of success from the EBLUS examinations that were conducted during the European Urology Residents Education Programme (EUREP) and other international and national dedicated ESU events. DESIGN, SETTING, AND PARTICIPANTS: ESU has been delivering EBLUS courses and examinations over the past 6 yr (2013-2018) in more than 40 countries worldwide. Trainees were asked about their laparoscopic background (procedures assisted/performed) and about the availability of HOT or simulator/box trainer in their facility. Apart from the online theoretical course, 4 HOT tasks [(1) peg transfer, (2) pattern cutting, (3) single knot tying, and (4) clip and cut] with its quality assessment of depth perception, bimanual dexterity, and efficiency were a part of the assessment and were considered critical to pass the EBLUS examination. RESULTS AND LIMITATIONS: A total of 875 EBLUS examinations were delivered (EUREP, n=385; other ESU events, n=490), with complete data available for 533 (61%) participants among which 295 (55%) passed the examinations. Pass rate increased on a yearly basis from 35% to 70% (p<0.001) and was similar between EUREP (56%) and other ESU/ESUT events (55%). The significant predictors of success were passing tasks 1 [odds ratio (OR): 869.9, 95% confidence interval (CI): 89.6-8449.0, p<0.001] and 2 (OR: 3045.0, 95% CI: 99.2-93 516.2, p<0.001) of the examinations. A limitation of EBLUS was its inability to provide more advanced training such as wet-lab or cadaveric training. CONCLUSIONS: Over the past few years more trainees have passed the European Basic Laparoscopic Urological Skills (EBLUS) examinations. Trainees who spend more time on laparoscopic procedures demonstrated a better performance and pass rate. We found almost no difference between the EBLUS results collected from EUREP and other ESU/ESUT events, which confirms the robustness of the training and examinations conducted worldwide. PATIENT SUMMARY: Training in laparoscopy helps trainees pass the European Basic Laparoscopic Urological Skills (EBLUS) examinations, reflected by an increase in the pass rate over the past 6 yr. Our results also confirm the robustness of EBLUS training and examinations worldwide.


Subject(s)
Biomedical Technology/education , Clinical Competence , Educational Measurement , Laparoscopy/education , Urologic Surgical Procedures/education , Urology/education , Europe , Humans , Schools, Medical , Time Factors
10.
Small ; 15(46): e1903025, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31573772

ABSTRACT

The predicted quasiparticle energy gap of more than 1 eV in sub-6 nm graphene nanoribbons (GNRs) is elusive, as it is strongly suppressed by the substrate dielectric screening. The number of techniques that can produce suspended high-quality and electrically contacted GNRs is small. The helium ion beam milling technique is capable of achieving sub-5 nm patterning; however, the functional device fabrication and the electrical characteristics are not yet reported. Here, the electrical transport measurement of suspended ≈6 nm wide mono- and bilayer GNR functional devices is reported, which are obtained through sub-nanometer resolution helium ion beam milling with controlled total helium ion budget. The transport gap opening of 0.16-0.8 eV is observed at room temperature. The measured transport gap of the different edge orientated GNRs is in good agreement with first-principles simulation results. The enhanced electron-electron interaction and reduced dielectric screening in the suspended quasi-1D GNRs and anti-ferromagnetic coupling between opposite edges in the zigzag GNRs substantiate the observed large transport gap.

11.
Eur Urol Focus ; 5(6): 1152-1156, 2019 11.
Article in English | MEDLINE | ID: mdl-29550077

ABSTRACT

BACKGROUND: The European School of Urology (ESU) started the European Urology Residents Education Programme (EUREP) in 2003 for final year urology residents, with hands-on training (HOT) added later in 2007. OBJECTIVE: To assess the geographical reach of EUREP, trainee demographics, and individual quality feedback in relation to annual methodology improvements in HOT. DESIGN, SETTING, AND PARTICIPANTS: From September 2014 to October 2017 (four EUREP courses) several new features have been applied to the HOT format of the EUREP course: 1:1 training sessions (2015), fixed 60-min time slots (2016), and standardised teaching methodology (2017). The resulting EUREP HOT format was verified by collecting and prospectively analysing the following data: total number of participants attending different HOT courses; participants' age; country of origin; and feedback obtained annually. RESULTS AND LIMITATIONS: A total of 796 participants from 54 countries participated in 1450 HOT sessions over the last 4 yr. This included 294 (20%) ureteroscopy (URS) sessions, 237 (16.5%) transurethral resection (TUR) sessions, 840 (58%) basic laparoscopic sessions, and 79 (5.5%) intermediate laparoscopic sessions. While 712 residents (89%) were from Europe, 84 (11%) were from non-European nations. Of the European residents, most came from Italy (16%), Germany (15%), Spain (15%), and Romania (8%). Feedback for the basic laparoscopic session showed a constant improvement in scores over the last 4 yr, with the highest scores achieved last year. This included feedback on improvements in tutor rating (p=0.017), organisation (p<0.001), and personal experience with EUREP (p<0.001). Limitations lie in the difficulties associated with the use of an advanced training curriculum with wet laboratory or cadaveric courses in this format, although these could be performed in other training centres in conjunction with EUREP. CONCLUSIONS: The EUREP trainee demographics show that the purpose of the course is being achieved, with excellent feedback reported. While European trainees dominate the demographics, participation from a number of non-European countries suggests continued ESU collaboration with other national societies and wider dissemination of simulation training worldwide. PATIENT SUMMARY: In this paper we look at methodological improvements and feedback for the European Urology Residents Education Programme hands-on-training over the last 4 yr.


Subject(s)
Internship and Residency/standards , Ureteroscopy/education , Urologic Surgical Procedures/education , Urology/education , Adult , Cadaver , Clinical Competence/statistics & numerical data , Curriculum/statistics & numerical data , Europe/epidemiology , Germany/epidemiology , Humans , Italy/epidemiology , Laparoscopy/education , Middle Aged , Romania/epidemiology , Simulation Training/methods , Spain/epidemiology , Transurethral Resection of Prostate/education
12.
Nanomaterials (Basel) ; 8(10)2018 Oct 10.
Article in English | MEDLINE | ID: mdl-30308934

ABSTRACT

Here, we systematically investigated the influence of ion bombardment with different fluences on the strength and direction of the exchange bias coupling in Au/Co/NiO systems with perpendicular magnetic anisotropy of the Co layer. We found that the direction of the exchange bias coupling can be reversed as a result of ion bombardment performed in an external magnetic field which is in the opposite direction to the magnetic field applied during film deposition. Moreover, the strength of the exchange bias coupling can be tailored by varying the ion fluence. These results show behaviors similar to the results found for systems of ferromagnetic layers with in-plane anisotropy. Our experimental work, supported by a two-energy-level model, demonstrates that exchange bias coupling can be tuned in a layered system with perpendicular magnetic anisotropy using ion bombardment.

13.
Nanotechnology ; 29(23): 235605, 2018 Jun 08.
Article in English | MEDLINE | ID: mdl-29557785

ABSTRACT

Carbon nanoscrolls (CNS) with their open ended morphology have recently attracted interest due to the potential application in gas capture, biosensors and interconnects. However, CNS currently suffer from the same issue that have hindered widespread integration of CNTs in sensors and devices: formation is done ex situ, and the tubes have to be placed with precision and reliability-a difficult task with low yield. Here, we demonstrate controlled in situ formation of electrically contacted CNS from suspended graphene nanoribbons with slight tensile stress. Formation probability depends on the length to width aspect ratio. Van der Waals interaction between the overlapping layers fixes the nanoscroll once formed. The stability of these CNSs is investigated by helium nano ion beam assisted in situ cutting. The loose stubs remain rolled and mostly suspended unless subject to a moderate helium dose corresponding to a damage rate of 4%-20%. One CNS stub remaining perfectly straight even after touching the SiO2 substrate allows estimation of the bending moment due to van der Waals force between the CNS and the substrate. The bending moment of 5400 eV is comparable to previous theoretical studies. The cut CNSs show long-term stability when not touching the substrate.

14.
ACS Appl Mater Interfaces ; 10(12): 10362-10368, 2018 Mar 28.
Article in English | MEDLINE | ID: mdl-29485851

ABSTRACT

Graphene nanomesh (GNM) is formed by patterning graphene with nanometer-scale pores separated by narrow necks. GNMs are of interest due to their potential semiconducting characteristics when quantum confinement in the necks leads to an energy gap opening. GNMs also have potential for use in phonon control and water filtration. Furthermore, physical phenomena, such as spin qubit, are predicted at pitches below 10 nm fabricated with precise structural control. Current GNM patterning techniques suffer from either large dimensions or a lack of structural control. This work establishes reliable GNM patterning with a sub-10 nm pitch and an < 4 nm pore diameter by the direct helium ion beam milling of suspended monolayer graphene. Due to the simplicity of the method, no postpatterning processing is required. Electrical transport measurements reveal an effective energy gap opening of up to ∼450 meV. The reported technique combines the highest resolution with structural control and opens a path toward GNM-based, room-temperature semiconducting applications.

15.
Scand J Urol ; 51(2): 114-119, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28635569

ABSTRACT

OBJECTIVE: The aim of this study was to construct a stratification model based on early postoperative kinetics of prostate-specific antigen (PSA) to select the most suitable high-risk patients for early intervention after radical prostatectomy (RP). MATERIALS AND METHODS: The study evaluated 205 men who had undergone RP without any adjuvant treatment. All of the patients had positive surgical margins, extracapsular extension and/or seminal vesicle invasion. The patients underwent multiple ultrasensitive PSA measurements on days 14, 30, 60 and 90 after RP, and subsequently at 3 month intervals. The ability of particular PSA measurements to predict biochemical recurrence (BCR) was assessed using the area under the curve (AUC). A sequential mathematical decision procedure was constructed to create a stratification model. RESULTS: During the median follow-up of 45.9 months, 106 patients (51%) experienced BCR. Prediction of BCR in terms of the AUC for PSA measurements on days 14, 30, 60 and 90 after the surgery was 0.61, 0.70, 0.80 and 0.82, respectively. In the multivariate analysis, only PSA after RP remained as a predictor of progression-free survival (p < 0.001). The stratification model based on calculated cut-off values for PSA on day 30 (0.068 ng/ml) and PSA on day 60 (0.015 ng/ml) reduced the potential overtreatment rate by 37%. CONCLUSIONS: The results imply that ultrasensitive PSA values obtained very early after RP correlate with the presence of recurrent disease in high-risk patients. Incorporating these readily available variables into risk stratification models may help to individualize the administration of adjuvant radiotherapy and thus to minimize overtreatment.


Subject(s)
Neoplasm Recurrence, Local/blood , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/surgery , Unnecessary Procedures/statistics & numerical data , Aged , Aged, 80 and over , Area Under Curve , Disease-Free Survival , Humans , Male , Middle Aged , Postoperative Period , Prostatectomy , Prostatic Neoplasms/radiotherapy , ROC Curve , Radiotherapy, Adjuvant , Risk Assessment/methods , Time Factors
16.
Microsc Microanal ; 23(4): 758-768, 2017 08.
Article in English | MEDLINE | ID: mdl-28487005

ABSTRACT

The recent technological advance of the gas field ion source (GFIS) and its successful integration into systems has renewed the interest in the focused ion beam (FIB) technology. Due to the atomically small source size and the use of light ions, the limitations of the liquid metal ion source are solved as device dimensions are pushed further towards the single-digit nanometer size. Helium and neon ions are the most widely used, but a large portfolio of available ion species is desirable, to allow a wide range of applications. Among argon and hydrogen, $${\rm N}_{2}^{{\plus}} $$ ions offer unique characteristics due to their covalent bond and their use as dopant for various carbon-based materials including diamond. Here, we provide a first look at the $${\rm N}_{2}^{{\plus}} $$ GFIS-FIB enabled imaging of a large selection of microscopic structures, including gold on carbon test specimen, thin metal films on insulator and nanostructured carbon-based devices, which are among the most actively researched materials in the field of nanoelectronics. The results are compared with images acquired by He+ ions, and we show that $${\rm N}_{2}^{{\plus}} $$ GFIS-FIB can offer improved material contrast even at very low imaging dose and is more sensitive to the surface roughness.

17.
Nanoscale ; 9(4): 1662-1669, 2017 Jan 26.
Article in English | MEDLINE | ID: mdl-28074959

ABSTRACT

The transformation of systematic vacuum and hydrogen annealing effects in graphene devices on the SiO2 surface is reported based on experimental and van der Waals interaction corrected density functional theory (DFT) simulation results. Vacuum annealing removes p-type dopants and reduces charged impurity scattering in graphene. Moreover, it induces n-type doping into graphene, leading to the improvement of the electron mobility and conductivity in the electron transport regime, which are reversed by exposing to atmospheric environment. On the other hand, annealing in hydrogen/argon gas results in smaller n-type doping along with a decrease in the overall conductivity and carrier mobility. This degradation of the conductivity is irreversible even the graphene devices are exposed to ambience. This was clarified by DFT simulations: initially, silicon dangling bonds were partially terminated by hydrogen, subsequently, the remaining dangling bonds became active and the distance between the graphene and SiO2 surface decreased. Moreover, both annealing methods affect the graphene channel including the vicinity of the metal contacts, which plays an important role in asymmetric carrier transport.

18.
Nanoscale ; 8(12): 6659-65, 2016 Mar 28.
Article in English | MEDLINE | ID: mdl-26948477

ABSTRACT

The direct growth of graphene on insulating substrate is highly desirable for the commercial scale integration of graphene due to the potential lower cost and better process control. We report a simple, direct deposition of nanocrystalline graphene (NCG) on insulating substrates via catalyst-free plasma-enhanced chemical vapor deposition at relatively low temperature of ∼800 °C. The parametric study of the process conditions that we conducted reveals the deposition mechanism and allows us to grow high quality films. Based on such film, we demonstrate the fabrication of a large-scale array of nanoelectromechanical (NEM) switches using regular thin film process techniques, with no transfer required. Thanks to ultra-low thickness, good uniformity, and high Young's modulus of ∼0.86 TPa, NCG is considered as a promising material for high performance NEM devices. The high performance is highlighted for the NCG switches, e.g. low pull-in voltage <3 V, reversible operations, minimal leakage current of ∼1 pA, and high on/off ratio of ∼10(5).

19.
Tumour Biol ; 36(3): 2121-6, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25407489

ABSTRACT

The receptor for advanced glycation end products (RAGE) and its ligands are involved in the pathogenesis of cancer. Glyoxalase I (GLO1) is an enzyme which detoxifies advanced glycation end product (AGE) precursors. The aim of the study was to find out the relationship between four polymorphisms (single nucleotide polymorphism, SNP) of the RAGE gene (AGER) and one SNP of the GLO1 gene and clear cell renal cancer (ccRCC). All polymorphisms (rs1800625 RAGE -429T/C, rs1800624 -374T/A, rs3134940 2184A/G, rs2070600 557G/A (G82S), and GLO1 rs4746 419A/C(E111A)) were determined by PCR-RFLP in 214 patients with ccRCC. A group of 154 healthy subjects was used as control. We found significant differences in the allelic and genotype frequencies of GLO1 E111A (419A/C) SNP between patients and controls-higher frequency of the C allele in ccRCC-58.6 vs. 44.5% in controls, OR (95% CI) 1.77 (1.32-2.38), p = 0.0002 (corrected p = 0.001); OR (95% CI) CC vs. AA 2.76 (1.5-4.80), p = 0.0004 (corrected p = 0.002); and AC+CC vs. AA 2.03 (1.23-3.30), p = 0.0034 (corrected p = 0.017). High aggressiveness of the tumor (grade 4) was associated with the presence of C allele RAGE -429T/C SNP (original p = 0.001, corrected p = 0.005) and G allele RAGE 2184A/G SNP (p < 0.001 and p < 0.005), and for genotypes RAGE -429CC (original p = 0.008, corrected p = 0.04) and RAGE 2184GG SNP (original p = 0.005, corrected p = 0.025). Our results demonstrate the link of E111A GLO1 SNP to the presence of the tumor and the connection of RAGE -429T/C and 2184A/G SNPs with the aggressiveness of the tumor. Further studies are required, especially with respect to potential therapeutic implications.


Subject(s)
Carcinoma, Renal Cell/genetics , Glycation End Products, Advanced/genetics , Kidney Neoplasms/genetics , Lactoylglutathione Lyase/genetics , Receptor for Advanced Glycation End Products/genetics , Alleles , Gene Frequency , Genotype , Humans , Middle Aged , Polymorphism, Single Nucleotide
20.
BMC Urol ; 14: 79, 2014 Oct 02.
Article in English | MEDLINE | ID: mdl-25277310

ABSTRACT

BACKGROUND: It is well recognized that the presence of positive surgical margins (PSM) after radical prostatectomy (RP) adversely affects cancer specific outcomes and recent evidence from randomized trials supports the use of adjuvant radiotherapy in these cases. However, not all of the patients with PSM develop disease recurrence and the policy of adjuvant radiation could result in considerable over-treatment. We investigated the ability of early postoperative prostate specific antigen (PSA) and PSA decline rates to stratify the risk of disease progression during the first weeks after the surgery thereby allowing adequate time for planning eventual adjuvant therapy. METHODS: We studied 116 consecutive patients with the finding of PSM after RP for localized prostate cancer between 2001 and 2012. No patients were treated with radiation or hormonal therapy. An intensive postoperative PSA monitoring using ultrasensitive assay started first at day 14 after the surgery, then at day 30, 60, 90 and 180, and subsequently in 3 monthly intervals. Biochemical recurrence (BCR) presented the failure of surgical treatment and it was defined as PSA ≥0.2 ng/ml. The ability of PSA decline parameters to predict BCR was assessed using Cox regression model and area under the curve (AUC) calculation. RESULTS: Overall 55 (47%) patients experienced BCR during median follow-up of 31.4 months (range 6-69). Preoperative PSA, pathologic Gleason sum and pathologic grade failed to reveal any association with observation of BCR. Postoperative PSA levels achieved significant predictive accuracy already on day 30 (AUC 0.74). PSA >0.073 ng/ml at day 30 increased significantly the risk of BCR (HR 4.35, p < 0.001). Predictive accuracy was significantly exceeded on day 60 (AUC 0.84; p < 0.001), while further enhancements on day 90 (AUC 0.84) and 180 (AUC 0.91) were not significant. CONCLUSIONS: The level of ultrasensitive PSA yields valuable information about the prostatectomy outcome already at the first month after the surgery and should aid risk stratification in patients with PSM. Patients not likely to experience subsequent disease progression may be spared the toxicity of immediate adjuvant radiotherapy.


Subject(s)
Postoperative Period , Prostate-Specific Antigen/blood , Prostatectomy , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Aged , Disease Progression , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Recurrence, Local , Prostatic Neoplasms/blood , Radiotherapy, Adjuvant , Risk Factors
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