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Functionalization of Ti64 via Direct Laser Interference Patterning and Its Influence on Wettability and Oxygen Bubble Nucleation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:2918-2929. [PMID: 38295345 PMCID: PMC10867896 DOI: 10.1021/acs.langmuir.3c02863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/30/2023] [Accepted: 01/04/2024] [Indexed: 02/02/2024]
Abstract
The nucleation of bubbles on solid surfaces is an important phenomenon in nature and technological processes like electrolysis. During proton-exchange membrane electrolysis, the nucleation and separation of the electrically nonconductive oxygen in the anodic cycle plays a crucial role to minimize the overpotential it causes in the system. This increases the efficiency of the process, making renewable energy sources and the "power-to-gas" strategy more viable. A promising approach is to optimize gas separation by surface functionalization in order to apply a more advantageous interface to industrial materials. In this work, the connection between the wettability and bubble nucleation of oxygen is investigated. For tailoring the wettability of Ti64 substrates, the direct laser interference patterning method is applied. A laser source with a wavelength of 1064 nm and a pulse duration of 12 ps is used to generate periodic pillar-like structures with different depths up to ∼5 μm. The resulting surface properties are characterized by water contact angle measurement, scanning electron microscopy, confocal microscopy, and X-ray photon spectroscopy. It was possible to generate structures with a water contact angle ranging from 20° up to nearly superhydrophobic conditions. The different wettabilities are validated based on X-ray photon spectroscopy and the different elemental composition of the samples. The results indicate that the surface character of the substrate adapts depending on the surrounding media and needs more time to reach a steady state for deeper structures. A custom setup is used to expose the functionalized surfaces to oxygen-oversaturated solutions. It is shown that a higher hydrophobicity of the structured surface yields a stronger interaction with the dissolved gas. This significantly enhances the oxygen nucleation up to nearly 350% by generating approximately 20 times more nucleation spots, but also smaller bubble sizes and a reduced detachment rate.
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Hydrogen Bubble Size Distribution on Nanostructured Ni Surfaces: Electrochemically Active Surface Area Versus Wettability. ACS APPLIED MATERIALS & INTERFACES 2023; 15:18290-18299. [PMID: 37010817 DOI: 10.1021/acsami.2c22231] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Emerging manufacturing technologies make it possible to design the morphology of electrocatalysts on the nanoscale in order to improve their efficiency in electrolysis processes. The current work investigates the effects of electrode-attached hydrogen bubbles on the performance of electrodes depending on their surface morphology and wettability. Ni-based electrocatalysts with hydrophilic and hydrophobic nanostructures are manufactured by electrodeposition, and their surface properties are characterized. Despite a considerably larger electrochemically active surface area, electrochemical analysis reveals that the samples with more pronounced hydrophobic properties perform worse at industrially relevant current densities. High-speed imaging shows significantly larger bubble detachment radii with higher hydrophobicity, meaning that the electrode surface area that is blocked by gas is larger than the area gained by nanostructuring. Furthermore, a slight tendency toward bubble size reduction of 7.5% with an increase in the current density is observed in 1 M KOH.
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On the design and development of foamed GO-hydrogel nanocomposite surfaces by ultra-short laser processing. NANOTECHNOLOGY 2023; 34:245701. [PMID: 36827699 DOI: 10.1088/1361-6528/acbeb4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 02/24/2023] [Indexed: 06/18/2023]
Abstract
Graphene oxide (GO) and reduced graphene oxide have outstanding qualities that could be exploited as reinforcement and antibacterial agents in a plethora of biomedical applications. In this contribution, it is reported the deployment of a polyacrylamide GO-hydrogel composite (GO@pAAm) which was photo-converted and structured by ultra-short laser irradiation using a direct laser writing (DLW) approach. The materials were characterized by Fourier Transform Infrared spectroscopy, scanning electron microscopy and confocal microscopy. The laser structure generates a multi-photo-induced effect: surface foaming and patterning, microdomains with enhanced selective water-swelling and effective GO photo-reduction. A first laser scan seems likely to induce the photo-reduction of GO and subsequent laser pulses trigger the structure/foaming. The photo-reduction of GO is evidenced by Raman spectroscopy by the relatively changing intensities of the D to G signals. Macroscopically by an increase in conductivity (decrease in sheet resistance fromRS-GO@pAAm= 304 ± 20 kΩ sq-1toRS-rGO@pAAm-DLW= 27 ± 8 kΩ sq-1) suggesting a reduction of the material measured by 4-Point-Probe.
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Tailored Laser Structuring of Tungsten Carbide Cutting Tools for Improving Their Tribological Performance in Turning Aluminum Alloy Al6061 T6. MATERIALS (BASEL, SWITZERLAND) 2023; 16:1205. [PMID: 36770212 PMCID: PMC9921853 DOI: 10.3390/ma16031205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/25/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
In times of societal development, sustainability has become a major concern for many manufacturers in the metal industries. In this context, surface texturing of cutting tools offers a promising approach in terms of reducing energy consumption and material waste. In this work, direct laser interference patterning is utilized for producing periodic line-like structures with spatial periods of 2.0 µm and 5.5 µm on rake-flank faces of cemented tungsten carbide cutting inserts. Structure depths up to 1.75 µm are reached by controlling the applied number of laser pulses. Turning experiments under lubricated conditions carried out on Al 6061 T6 parts with textured and untreated tools are performed to determine their tribological performances. The used textured cutting tools can effectively decrease machining forces up to 17% due to the corresponding improvement in frictional behavior at the tool/chip interface. Furthermore, the laser-processed tools produce thinner chips and decrease the surface roughness by 31% of the aluminum work piece.
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INVESTIGATING THE EFFECT OF INSPIRED OXYGEN FRACTION ON RIGHT VENTRICULAR 3D STRAIN DURING GENERAL ANAESTHESIA IN PATIENTS WITH STABLE CORONARY ARTERY DISEASE. J Cardiothorac Vasc Anesth 2022. [DOI: 10.1053/j.jvca.2022.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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Aviation Contrail Cirrus and Radiative Forcing Over Europe During 6 Months of COVID-19. GEOPHYSICAL RESEARCH LETTERS 2021; 48:e2021GL092771. [PMID: 34230716 PMCID: PMC8250229 DOI: 10.1029/2021gl092771] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/24/2021] [Accepted: 03/31/2021] [Indexed: 05/30/2023]
Abstract
The COVID-19 pandemic led to a 72% reduction of air traffic over Europe in March-August 2020 compared to 2019. Modeled contrail cover declined similarly, and computed mean instantaneous radiative contrail forcing dropped regionally by up to 0.7 W m-2. Here, model predictions of cirrus optical thickness and the top-of-atmosphere outgoing longwave and reflected shortwave irradiances are tested by comparison to Meteosat-SEVIRI-derived data. The agreement between observations and modeled data is slightly better when modeled contrail cirrus contributions are included. The spatial distributions and diurnal cycles of the differences in these data between 2019 and 2020 are partially caused by differences in atmospheric and surface conditions, particularly for solar radiation in the spring of 2020. Aviation signals become discernible in the observed differences of these data between 2019 and 2020 when subtracting numerical weather prediction model results that approximate the atmosphere and surface conditions without contrails.
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Hierarchical Microtextures Embossed on PET from Laser-Patterned Stamps. MATERIALS (BASEL, SWITZERLAND) 2021; 14:1756. [PMID: 33918342 PMCID: PMC8038280 DOI: 10.3390/ma14071756] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 12/19/2022]
Abstract
Nowadays, the demand for surface functionalized plastics is constantly rising. To address this demand with an industry compatible solution, here a strategy is developed for producing hierarchical microstructures on polyethylene terephthalate (PET) by hot embossing using a stainless steel stamp. The master was structured using three laser-based processing steps. First, a nanosecond-Direct Laser Writing (DLW) system was used to pattern dimples with a depth of up to 8 µm. Next, the surface was smoothed by a remelting process with a high-speed laser scanning at low laser fluence. In the third step, Direct Laser Interference Patterning (DLIP) was utilized using four interfering sub-beams to texture a hole-like substructure with a spatial period of 3.1 µm and a depth up to 2 µm. The produced stamp was used to imprint PET foils under controlled temperature and pressure. Optical confocal microscopy and scanning electron microscopy imaging showed that the hierarchical textures could be accurately transferred to the polymer. Finally, the wettability of the single- and multi-scaled textured PET surfaces was characterized with a drop shape analyzer, revealing that the highest water contact angles were reached for the hierarchical patterns. Particularly, this angle was increased from 77° on the untreated PET up to 105° for a hierarchical structure processed with a DLW spot distance of 60 µm and with 10 pulses for the DLIP treatment.
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Correction to: Prognostic impact of gross tumor volume during radical radiochemotherapy of locally advanced non-small cell lung cancer-results from the NCT03055715 multicenter cohort study of the Young DEGRO Trial Group. Strahlenther Onkol 2021; 197:560-561. [PMID: 33674905 PMCID: PMC8154766 DOI: 10.1007/s00066-021-01750-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Prognostic impact of gross tumor volume during radical radiochemotherapy of locally advanced non-small cell lung cancer-results from the NCT03055715 multicenter cohort study of the Young DEGRO Trial Group. Strahlenther Onkol 2021; 197:385-395. [PMID: 33410959 PMCID: PMC8062351 DOI: 10.1007/s00066-020-01727-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 11/30/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND In radical radiochemotherapy (RCT) of inoperable non-small-cell lung cancer (NSCLC) typical prognostic factors include T- and N-stage, while there are still conflicting data on the prognostic relevance of gross tumor volume (GTV) and particularly its changes during RCT. The NCT03055715 study of the Young DEGRO working group of the German Society of Radiation Oncology (DEGRO) evaluated the prognostic impact of GTV and its changes during RCT. METHODS A total of 21 university centers for radiation oncology from five different European countries (Germany, Switzerland, Spain, Belgium, and Austria) participated in the study which evaluated n = 347 patients with confirmed (biopsy) inoperable NSCLC in UICC stage III A/B who received radical curative-intent RCT between 2010 and 2013. Patient and disease data were collected anonymously via electronic case report forms and entered into the multi-institutional RadPlanBio platform for central data analysis. GTV before RCT (initial planning CT, GTV1) and at 40-50 Gy (re-planning CT for radiation boost, GTV2) was delineated. Absolute GTV before/during RCT and relative GTV changes were correlated with overall survival as the primary endpoint. Hazard ratios (HR) of survival analysis were estimated by means of adjusted Cox regression models. RESULTS GTV1 was found to have a mean of 154.4 ml (95%CI: 1.5-877) and GTV2 of 106.2 ml (95% CI: 0.5-589.5), resulting in an estimated reduction of 48.2 ml (p < 0.001). Median overall survival (OS) was 18.8 months with a median of 22.1, 20.9, and 12.6 months for patients with high, intermediate, and low GTV before RT. Considering all patients, in one survival model of overall mortality, GTV2 (2.75 (1.12-6.75, p = 0.03) was found to be a stronger survival predictor than GTV1 (1.34 (0.9-2, p > 0.05). In patients with available data on both GTV1 and GTV2, absolute GTV1 before RT was not significantly associated with survival (HR 0-69, 0.32-1.49, p > 0.05) but GTV2 significantly predicted OS in a model adjusted for age, T stage, and chemotherapy, with an HR of 3.7 (1.01-13.53, p = 0.04) per 300 ml. The absolute decrease from GTV1 to GTV2 was correlated to survival, where every decrease by 50 ml reduced the HR by 0.8 (CI 0.64-0.99, p = 0.04). There was no evidence for a survival effect of the relative change between GTV1 and GTV2. CONCLUSION Our results indicate that independently of T stage, the re-planning GTV during RCT is a significant and superior survival predictor compared to baseline GTV before RT. Patients with a high absolute (rather than relative) change in GTV during RT show a superior survival outcome after RCT.
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Evaluation of Two Fosphenytoin Loading Dose Regimens and Monitoring in Infants and Neonates Less Than Six Months of Age. J Pediatr Pharmacol Ther 2020; 25:617-622. [PMID: 33041716 DOI: 10.5863/1551-6776-25.7.617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES The objectives of the study were to compare the free serum concentrations after different fosphenytoin loading dose strategies in patients younger than 6 months old and to investigate the frequency of seizure cessation following a loading dose of fosphenytoin. METHODS This retrospective cohort study included neonates and infants admitted to a 150-bed children's hospital between August 1, 2014, and February 1, 2018. Patients were included if they were younger than 6 months old and had a postload free phenytoin serum concentration collected during the specified time frame. Patients were identified through a database query screening for the inclusion criteria. Patients were separated into 2 groups with the 15 mg/kg group as per protocol and the 20 mg/kg group as noted in common practice. Data collection included demographic information, fosphenytoin dose, time of administration of the fosphenytoin loading dose, time of sampling, free phenytoin serum concentration results, concomitant antiepileptic agents, albumin serum concentration, and total bilirubin serum concentration. RESULTS Forty-one patients were included for analysis, 12 in the 15 mg/kg group and 29 in the 20 mg/kg group. The average free phenytoin concentration after the loading dose was 2.45 ± 0.54 mg/L in the 15 mg/kg group and 2.52 ± 0.66 mg/L in the 20 mg/kg group. Seizure cessation after the fosphenytoin loading dose was achieved in 3 of 12 (25%) patients in the 15 mg/kg group and in 13 of 29 (45%) patients in the 20 mg/kg group (p = 0.305). CONCLUSIONS The study demonstrates that a traditional range of fosphenytoin loading dose (15-20 mg/kg) led to elevated postloading dose free phenytoin serum concentrations in the majority of patients with a seizure cessation rate of approximately 39%. The question remains as to what the optimal dose and target concentration should be in this patient population to achieve the best efficacy without risking associated toxicities.
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Abstract
Purpose This consensus statement from the Breast Cancer Working Group of the German Society for Radiation Oncology (DEGRO) aims to define practical guidelines for accelerated partial-breast irradiation (APBI). Methods Recent recommendations for relevant aspects of APBI were summarized and a panel of experts reviewed all the relevant literature. Panel members of the DEGRO experts participated in a series of conferences, supplemented their clinical experience, performed a literature review, and formulated recommendations for implementing APBI in clinical routine, focusing on patient selection, target definition, and treatment technique. Results Appropriate patient selection, target definition for different APBI techniques, and basic rules for appropriate APBI techniques for clinical routine outside of clinical trials are described. Detailed recommendations for APBI in daily practice, including dose constraints, are given. Conclusion Guidelines are mandatory to assure optimal results of APBI using different techniques.
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SP-0250 Lessons learnt from a young head of department. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)30670-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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A nano-carrier platform for the targeted delivery of nature-inspired antimicrobials using Engineered Water Nanostructures for food safety applications. Food Control 2018; 96:365-374. [PMID: 32132770 DOI: 10.1016/j.foodcont.2018.09.037] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Despite the progress in the area of food safety, foodborne diseases still represent a massive challenge to the public health systems worldwide, mainly due to the substantial inefficiencies across the farm-to-fork continuum. Here, we report the development of a nano-carrier platform, for the targeted and precise delivery of antimicrobials for the inactivation of microorganisms on surfaces using Engineered Water Nanostructures (EWNS). An aqueous suspension of an active ingredient (AI) was used to synthesize iEWNS, with the 'i' denoting the AI used in their synthesis, using a combined electrospray and ionization process. The iEWNS possess unique, active-ingredient-dependent physicochemical properties: i) they are engineered to have a tunable size in the nanoscale; ii) they have excessive electric surface charge, and iii) they contain both the reactive oxygen species (ROS) formed due to the ionization of deionized (DI) water, and the AI used in their synthesis. Their charge can be used in combination with an electric field to target them onto a surface of interest. In this approach, a number of nature-inspired antimicrobials, such as H2O2, lysozyme, citric acid, and their combination, were used to synthesize a variety of iEWNS-based nano-sanitizers. It was demonstrated through foodborne-pathogen-inactivation experiments that due to the targeted and precise delivery, and synergistic effects of AI and ROS incorporated in the iEWNS structure, a pico- to nanogram-level dose of the AI delivered to the surface using this nano-carrier platform is capable of achieving 5-log reductions in minutes of exposure time. This aerosol-based, yet 'dry' intervention approach using iEWNS nano-carrier platform offers advantages over current 'wet' techniques that are prevalent commercially, which require grams of the AI to achieve similar inactivation, leading to increased chemical risks and chemical waste byproducts. Such a targeted nano-carrier approach has the potential to revolutionize the delivery of antimicrobials for sterilization in the food industry.
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Human nasal mucosal C-reactive protein responses after inhalation of ultrafine welding fume particles: positive correlation to systemic C-reactive protein responses. Nanotoxicology 2018; 12:1130-1147. [DOI: 10.1080/17435390.2018.1498930] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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OC-0329: Predictive value of GTV in radiotherapy of NSCLC - early results of the NCT03055715 trial. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)30639-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Systemic serum amyloid A as a biomarker for exposure to zinc and/or copper-containing metal fumes. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2018; 28:84-91. [PMID: 28176762 DOI: 10.1038/jes.2016.86] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 12/06/2016] [Indexed: 06/06/2023]
Abstract
Zinc- and copper-containing welding fumes increase systemic C-reactive protein (CRP). The aim of this study was to investigate the performance of the biomarkers serum amyloid A (SAA) and soluble vascular cell adhesion molecule-1 (VCAM-1) in this regard. Fifteen male subjects were exposed under controlled conditions to welding fumes containing either zinc, or copper, or copper and zinc for 6 h. Plasma samples were collected before, 6 and 24 h after start of exposure and biomarkers therein were measured by electrochemiluminescent assay. For each exposure, systemic concentrations of systemic SAA, but not VCAM-1, increased significantly at 24 h after exposure start compared with baseline ("copper only": P=0.0005, "zinc only": P=0.027, "copper and zinc": P=0.001). SAA showed a wider range of concentrations than did CRP and its levels increased up to 19-fold after welding fume exposure. The recognition of copper as a potential harmful component in welding fumes, also independent from zinc, deserves further consideration. SAA might represent a new sensitive biomarker for potential subclinical sterile inflammation after inhalation of copper- and/or zinc-containing welding fumes. As elevations of CRP and SAA protein have both been linked to a higher risk for cardiovascular disease, these findings might particularly be important for long-term welders.
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OC-0086: Perioperative interstitial high-dose-rate (HDR) brachytherapy for the treatment of recurrent keloids. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)30530-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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[Description of a Multidimensional Health Program for Informal Caregivers]. DAS GESUNDHEITSWESEN 2016; 80:S51-S56. [PMID: 27756085 DOI: 10.1055/s-0042-112814] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The aim of this study is to describe the concept of a prevention program for informal caregivers and its fit into stress theory and quality criteria. The program combines a 4-day group intervention outside the home with individual professional care in familiar domestic surroundings (family health care for persons with high burden, home training for specific care aspects). The program applies strategies focusing on problems and emotions. The program can be financed by social security funds. The 4-day respite service closes a gap in health services for informal caregivers.
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Gesundheitskompetenz von Rehabilitandinnen und Rehabilitanden in Berufsförderungswerken. DAS GESUNDHEITSWESEN 2016. [DOI: 10.1055/s-0036-1586705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Synthesis of Industrially Relevant Carbamates towards Isocyanates using Carbon Dioxide and Organotin(IV) Alkoxides. CHEMSUSCHEM 2016; 9:1586-1590. [PMID: 27319978 DOI: 10.1002/cssc.201600580] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Indexed: 06/06/2023]
Abstract
A straightforward phosgene-free synthesis of aromatic isocyanates and diisocyanates is disclosed. Theoretical investigations suggested that the insertion of carbon dioxide (CO2 ) by dialkyltin(IV) dialkoxides could be used to convert aromatic amines into aromatic mono- and dicarbamates. Here we show, that methyl phenylcarbamate (MPC) from aniline using organotin(IV) dimethoxide and CO2 can be formed in high yield of up to 92 %, experimentally corroborating the predictions of density functional theory (DFT) calculations. MPC was then separated from the tin oxide residues and converted into phenyl isocyanate. Furthermore, organotin(IV) alkoxides could be regenerated from the tin oxide residues and reused, paving the way for a continuous industrial process. Extension of the scope to the synthesis of diurethanes from toluene 2,4-diamine and 4,4'-methylenedianiline could potentially allow the efficient production of industrially relevant diisocyanates.
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Prognose und Verhinderung von Abbrüchen bei Qualifizierungen in der beruflichen Rehabilitation. REHABILITATION 2016; 55:157-66. [DOI: 10.1055/s-0042-103205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Inducible T-cell receptor expression in precursor T cells for leukemia control. Leukemia 2015; 29:1530-42. [PMID: 25652739 DOI: 10.1038/leu.2015.20] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 12/01/2014] [Accepted: 01/13/2015] [Indexed: 12/14/2022]
Abstract
Co-transplantation of hematopoietic stem cells with those engineered to express leukemia-reactive T-cell receptors (TCRs) and differentiated ex vivo into precursor T cells (preTs) may reduce the risk of leukemia relapse. As expression of potentially self-(leukemia-) reactive TCRs will lead to negative selection or provoke autoimmunity upon thymic maturation, we investigated a novel concept whereby TCR expression set under the control of an inducible promoter would allow timely controlled TCR expression. After in vivo maturation and gene induction, preTs developed potent anti-leukemia effects. Engineered preTs provided protection even after repeated leukemia challenges by giving rise to effector and central memory cells. Importantly, adoptive transfer of TCR-transduced allogeneic preTs mediated anti-leukemia effect without evoking graft-versus-host disease (GVHD). Earlier transgene induction forced CD8(+) T-cell development was required to obtain a mature T-cell subset of targeted specificity, allowed engineered T cells to efficiently pass positive selection and abrogated the endogenous T-cell repertoire. Later induction favored CD4 differentiation and failed to produce a leukemia-reactive population emphasizing the dominant role of positive selection. Taken together, we provide new functional insights for the employment of TCR-engineered precursor cells as a controllable immunotherapeutic modality with significant anti-leukemia activity.
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Reaktionen von cis-Crotonsäurederivaten mit Cyclopentadien in heterogener Phase/ Reaction between cis-Crotonic Acid Derivatives and Cyclopentadiene in the Heterogeneous Phase. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-1981-0722] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Diels-Alder reactions between cyclopenta-diene and cis-crotonic acid derivatives were examined in the absorbed phase on various surfaces. The results indicate considerable differences under these conditions in the relative yields of exo and endo isomers. On silica gel, montigel, and aluminium oxide the reactions give mainly endo isomers.
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Photoinduzierte Dechlorierungsreaktion an Dichlorbenzolen, Anilinen und Phenolen in Gegenwart von Protonendonatoren/ Photoinduced Dechlorination Reaction of Dichlorobenzenes, Chloroanilins and Chlorophenols in the Presence of Protondonors. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-1979-0125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Photokinetic experiments show that the dechlorination reaction of dichlorobenzenes, chloroanilins, and chlorophenols is dependent on nature of solvent, but undependent on oxygen. Quantum yields determined in n-hexane indicate that there is a strong deviation within the ortho, meta, and para products.
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Abstract
Dimerizations and reactions with water of pyrimidine bases are the primary steps held responsible for the deformation of DNA at short wavelengths in vitro and in vivo experiments. However the influence of oxygen in combination with water on the UV deformation at wavelengths representative for troposphere is evident from the observed data and both together are needed to change the DNA structure. The only plausible explanation for the effect of oxygen is the formation of reactive oxygen species during the UV irradiation of DNA. In the present work the deformation of DNA by different oxygen species like singlet oxygen (1O2), superoxideanion (O2
-), hydroxyradical (·OH), ozone (O3) and hydrogenperoxide (H2O2) is excluded with the help of chemical-trapping experiments. The photo-induced transformation proceeds via excited states of DNA. which react with groundstate oxygen to afford peroxide.
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Detection of (133)Xe from the Fukushima nuclear power plant in the upper troposphere above Germany. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2014; 132:94-99. [PMID: 24607612 DOI: 10.1016/j.jenvrad.2014.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 01/30/2014] [Accepted: 02/03/2014] [Indexed: 06/03/2023]
Abstract
After the accident in the Japanese Fukushima Dai-ichi nuclear power plant in March 2011 large amounts of radioactivity were released and distributed in the atmosphere. Among them were also radioactive noble gas isotopes which can be used as tracers to test global atmospheric circulation models. This work presents unique measurements of the radionuclide (133)Xe from Fukushima in the upper troposphere above Germany. The measurements involve air sampling in a research jet aircraft followed by chromatographic xenon extraction and ultra-low background gas counting with miniaturized proportional counters. With this technique a detection limit of the order of 100 (133)Xe atoms in liter-scale air samples (corresponding to about 100 mBq/m(3)) is achievable. Our results provide proof that the (133)Xe-rich ground level air layer from Fukushima was lifted up to the tropopause and distributed hemispherically. Moreover, comparisons with ground level air measurements indicate that the arrival of the radioactive plume at high altitude over Germany occurred several days before the ground level plume.
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Nasal levels of soluble IL-33R ST2 and IL-16 in allergic rhinitis: inverse correlation trends with disease severity. Clin Exp Allergy 2014; 43:1134-43. [PMID: 24074331 DOI: 10.1111/cea.12148] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 04/16/2013] [Accepted: 05/08/2013] [Indexed: 11/27/2022]
Abstract
BACKGROUND Serum levels of IL-16, IL-33 and the decoy receptor of IL-33, soluble ST2, are elevated in allergic rhinitis. Recent studies show that IL-16, soluble ST2 or anti-IL-33 reduce type 2 cytokines (such as IL-5) and eosinophilia in murine models of allergic asthma or allergic rhinitis respectively. OBJECTIVE In this study, we studied the release of IL-5, IL-16, IL-33 and soluble ST2 in allergic rhinitis patients after nasal allergen challenge and natural pollen exposure. METHODS The nasal lavages of 15 allergic and 14 non-allergic volunteers were collected during the pollen allergy season. In addition, six allergic volunteers underwent unilateral nasal allergen and control challenge out of season and nasal secretions and sera were collected. IL-5, IL-16, IL-33 and soluble ST2 in nasal secretions and sera were measured by electrochemiluminescent assay or ELISA, respectively. RESULTS Nasal IL-5, IL-16 and soluble ST2 levels were significantly increased in seasonally pollen exposed allergic volunteers compared to control subjects (P < 0.001, P = 0.018 and P = 0.002 respectively), whereas IL-33 remained undetectable. Nasal IL-16 showed a weak inverse correlation trend with nasal symptoms (r = -0.48, P = 0.07). Nasal soluble ST2 concentrations were inversely correlated with nasal symptoms (r = -0.61, P = 0.02) and positively correlated with IL-16 (r = 0.56, P = 0.03). Significant increases of nasal IL-5, IL-16 and ST2 but not IL-33 were observed after nasal allergen challenge. At 24 h after allergen challenge, local ST2 and IL-5 concentrations showed an inverse correlation trend (r = -0.83, P = 0.04). Serum levels of IL-5, IL-16 and soluble ST2 rose in at least five of six volunteers tested at 5 or 24 h post-challenge. CONCLUSIONS AND CLINICAL RELEVANCE The observed upregulation of soluble ST2 and IL-16 after nasal allergen challenge and during peak pollination season suggests potential regulatory roles of these cytokines in the inflammatory reaction in allergic rhinitis.
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Dynamics of Molecular Photoionization Studied by Zero Kinetics Energy Photoelectron Spectroscopy. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/bbpc.198800085] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Preparation and electrochemistry of modified polypyrrole films by anodic copolymerization techniques. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/masy.19870080107] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Health-related quality of life in elderly cancer patients, elderly non-cancer patients and an elderly general population. Eur J Cancer Care (Engl) 2009; 18:457-65. [PMID: 19473377 DOI: 10.1111/j.1365-2354.2008.00975.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Health-related quality of life (QoL) is a major topic within the care for cancer patients (CP). Compared with the general population (GP), QoL of CP is worse in most dimensions; however, only few data comparing QoL of CP with that of other patients have been provided so far. We determined QoL with the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire in hospitalized patients aged 60 years and older: 195 CP and 130 patients treated for other medical disorders (MP). In addition, data were compared with an age- and gender-stratified German GP. Explorative statistical analyses were performed. The CP aged >or=70 years compared with those aged 60-69 years had decreased QoL in two scales, physical and cognitive functioning, MP in four scales, physical and role functioning, fatigue and dyspnoea respectively. Compared with the GP, both CP and MP had worse QoL in almost all scales. The CP and MP differed in two of 15 scales only, with CP having lower scores in emotional functioning and more loss of appetite. In conclusion, reduced QoL in elderly CP compared with GP cannot solely be attributed to the diagnosis of cancer, but also to a medical disorder requiring inpatient hospital care.
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Abstract
OBJECTIVE This study compared physiological differences between children diagnosed with migraine and their healthy peers. METHOD Physiological measures were obtained at baseline, after discussing an emotional stressor, and after a 5-min recovery period in 21 children with pediatric migraine and 32 healthy peers. Comparisons were also made on psychological measures investigating anxiety. RESULTS Children with migraine exhibited a significantly higher pulse rate compared to comparison children at rest, and higher diastolic blood pressure and higher low-frequency/high-frequency ratio after a 5-min recovery from an emotional stressor. Additionally, when anxiety was entered as a covariate, group differences after the 5-min recovery period were no longer significant. CONCLUSIONS Results suggest that relative to comparison children, children with migraine exhibit some physiological elevation at rest, as well as a prolonged physiological recovery period after an emotional stressor. Group differences after the 5-min recovery period suggest that children with migraine experience delayed sympathetic hyperarousal and prolonged sympathovagal imbalance. The treatment implications of these findings are discussed.
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Erratum: “Fetal dose estimates for radiotherapy during pregnancy-Case report of a young woman with medulloblastoma” [Med. Phys. 34, 2455 (2007)]. Med Phys 2008. [DOI: 10.1118/1.2979322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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TGF-beta1 Gene Polymorphism and Quality of Life in Prostate Cancer Patients Treated with Brachytherapy Seed Implantation. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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36
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Macrophage turnover kinetics in the lungs of mice infected with Streptococcus pneumoniae. Pneumologie 2007. [DOI: 10.1055/s-2007-1032294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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37
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Partial Volume Analysis Predicting Late Side Effects in LDR Brachytherapy of Prostate Cancer. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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38
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Real-Time PCR-Analyse für Östrogen-Rezeptor beta, Progesteronrezeptor und P-450-Aromatase im Menstrualblut – eine Pilotstudie über die Bedeutung des basalen Endometriums in der Pathogenese der Endometriose. Geburtshilfe Frauenheilkd 2007. [DOI: 10.1055/s-2007-989163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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SU-FF-T-335: Partial Volume Analysis in LDR Brachytherapy of Prostate Cancer - Comparison of Intraoperative Ultrasound Planning and Post Implant CT Dosimetry. Med Phys 2007. [DOI: 10.1118/1.2760998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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SU-FF-T-280: LDR Brachytherapy for Low Risk Prostate Cancer with I-125 - a Comparison of the Results with Loose Seeds From Two Different Producers. Med Phys 2007. [DOI: 10.1118/1.2760942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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SU-FF-T-234: Fetal Dose Estimates for Radiotherapy During Pregnancy - Case Report of a Young Woman with Medulloblastoma. Med Phys 2007. [DOI: 10.1118/1.2760895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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2314. Int J Radiat Oncol Biol Phys 2006. [DOI: 10.1016/j.ijrobp.2006.07.722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2587. Int J Radiat Oncol Biol Phys 2006. [DOI: 10.1016/j.ijrobp.2006.07.1000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Changes in leucocyte and lymphocyte subsets during tuberculosis treatment; prominence of CD3dimCD56+ natural killer T cells in fast treatment responders. Clin Exp Immunol 2006; 145:252-60. [PMID: 16879244 PMCID: PMC1809688 DOI: 10.1111/j.1365-2249.2006.03144.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The immune responses against pulmonary tuberculosis are still poorly defined. This study describes changes in leucocyte and lymphocyte subsets during treatment to find reliable immunological markers for the disease and treatment response. Flow cytometric peripheral blood immune phenotyping, routine haematology and sputum microbiology were performed on 21 HIV-negative adult tuberculosis (TB) patients with positive sputum cultures during therapy in comparison with 14 healthy purified protein derivative (PPD)-positive volunteers. Patients at diagnosis showed high absolute neutrophil and monocyte counts which fell during treatment but low lymphocyte subset counts which increased [except natural killer (NK) and NK T cells]. High counts of a population of CD3(dim)/CD56+ NK T cells at diagnosis correlated significantly with negative sputum culture after 8 weeks of treatment. A multivariate classification technique showed improved correlation when NK cells were taken into account. In conclusion, peripheral blood white cell counts change significantly during treatment and counts at diagnosis, especially CD3(dim)/CD56+ NK T cells, hold promise in predictive models of TB treatment response.
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Polymorphismen im Östrogenrezeptor-α bei Patientinnen mit Endometriose. Geburtshilfe Frauenheilkd 2006. [DOI: 10.1055/s-2006-952181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Videocapsule endoscopy is useful for the diagnosis of intestinal lymphangiectasia. Dig Liver Dis 2006; 38:699-703. [PMID: 16527553 DOI: 10.1016/j.dld.2006.01.027] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Revised: 01/26/2006] [Accepted: 01/31/2006] [Indexed: 12/11/2022]
Abstract
We study two authentic cases of protein-losing enteropathy, the diagnosis of which was facilitated using Given M2A videocapsule endoscopy. The first case corresponded to a primary intestinal lymphangiectasia confirmed by jejunum biopsies and the second one to a protein-losing enteropathy with lymphatic abnormalities secondary to a chronic constrictive pericarditis. In the first case, the mucosa of jejunum presented with a diffuse oedematous aspect, whitish villi, white curved lines probably related to submucosal dilated lymphatics and lacteal juice. In the second case, capsule endoscopy showed oedematous aspect of jejunum mucosa associated with white curved lines similar to those observed in the first case. Videocapsule endoscopy is useful in cases of protein-losing enteropathy to identify presence of intestinal lymphangiectasia and to specify their localisation after ruling out other disorders liable to induce protein-losing gastrointestinal syndrome.
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Assessment Center zur Erfassung sozialer Kompetenzen in der beruflichen Rehabilitation, Güte und Nutzen des neuen Verfahrens ASKOR. DAS GESUNDHEITSWESEN 2006. [DOI: 10.1055/s-2006-948563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Evaluation of clinical parameters and estrogen receptor alpha gene polymorphisms for patients with endometriosis. Reproduction 2006; 131:153-61. [PMID: 16388018 DOI: 10.1530/rep.1.00787] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Endometriosis is a chronic inflammatory disease, which is especially found in women with subfertility problems with an incidence of up to 30%. The disease is considered an estrogen-dependent disorder, where DNA polymorphisms of the estrogen receptor α (ERα) in connection with endometriosis are controversially discussed. From a German population of women, clinical data associated with the disease, including the American Fertility Society (AFS) I–IV classification, and non-clinical parameters were evaluated statistically in endometriosis patients (n= 98) and in control women (n= 98) without endometriosis. Using a multivariate statistical analysis, significant associations of endometriosis with dysmenorrhea (P< 0.001) and allergies against medicaments (P= 0.042) were found. A positive trend between first grade family history of endometriosis and allergies against medicaments was also observed, suggesting a genetic relationship. From both collectives, DNA from peripheral blood was analyzed for the frequency of the ERα DNA polymorphisms Xba1 (A/G) and PvuII (T/C) in intron 1 and the ERα exonic DNA polymorphism (G229A) with an amino acid exchange (Gly77Ser) in the transactivation domain. DNA samples from endometriosis lesions and control tissues from the same collectives were also analyzed for the exonic G229A polymorphism. Only homozygote wild-type alleles for the polymorphism G229A were found, making it a rare polymorphism in mid-European individuals. Allele types for the PvuII and Xba1 polymorphisms were analyzed with the observed statistically significant clinical parameters and showed no significant association with endometriosis; however a trend with AFS IV was noted, which could contribute to lesion severity. In conclusion, the analyzed polymorphisms in the ERα do not have a functional role concerning specific clinical parameters associated with endometriosis.
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Abstract
All vertebrate embryos produce a specific erythroid cell population--primitive erythrocytes--early in development. These cells are characterized by expression of the specific embryonic haemoglobins. Many aspects of primitive erythropoiesis and the physiological function of primitive red cells are still enigmatic. Nevertheless, recent years have seen intensive efforts to characterize in greater detail the molecular events underlying the initiation of erythropoiesis in vertebrate embryos. Several key genes have been identified that are necessary for primitive and the subsequent definitive erythropoiesis, which differs in several aspect from primitive erythropoiesis. This review gives in its first part a short overview dealing with comparative aspects of primitive and early definitive erythropoiesis in higher and lower vertebrates and in the second part we discuss the physiological function of primitive red cells based mainly on results from mammalian and avian embryos.
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[Development of a new test for speech audiometry in children and results in CI children]. Laryngorhinootologie 2005; 84:738-43. [PMID: 16231241 DOI: 10.1055/s-2005-861375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Speech audiometry plays an important role for hearing evaluation in children. Hearing impaired children, such as those with cochlear implant (CI) who frequently undergo testing, learn the test words by heart. Furthermore, the standard tests use words of former time. PATIENTS AND METHODS Using the most frequently words of modern children's literature a speech assessment test was developed for children between 1 to 8 years. The material was first evaluated on normal hearing children. In a second step the phoneme and word perception scores of 35 CI children were measured using 60 - 100 dB SPL according to the most comfortable level (MCL) in free sound field. RESULTS The performance-intensity function for the single words were highly comparable with those of the Freiburger or Göttinger speech perception test. The average speech reception threshold in CI children was 44 % (test I), 36 % (test II), 63 % (test III) and 69 % (test IV), respectively. Compared to the Mainzer and Göttinger speech perception test the new words were more difficult to understand than those of the known tests. However, a statistically significant difference could be noted only for test II. CONCLUSIONS The new developed "Würzburger speech perception test" appears to be a useful additional tool for the evaluation of hearing impaired children in addition to the standard test procedures.
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