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1.
Phys Rev Lett ; 129(2): 027002, 2022 Jul 08.
Article En | MEDLINE | ID: mdl-35867432

Superconductivity in infinite-layer nickelates holds exciting analogies with that of cuprates, with similar structures and 3d-electron count. Using resonant inelastic x-ray scattering, we studied electronic and magnetic excitations and charge density correlations in Nd_{1-x}Sr_{x}NiO_{2} thin films with and without an SrTiO_{3} capping layer. We observe dispersing magnons only in the capped samples, progressively dampened at higher doping. We detect an elastic resonant scattering peak in the uncapped x=0 compound at wave vector (∼⅓,0), remindful of the charge order signal in hole doped cuprates. The peak weakens at x=0.05 and disappears in the superconducting x=0.20 film. The role of the capping on the electronic reconstruction far from the interface remains to be understood.

3.
J Eur Acad Dermatol Venereol ; 24(7): 756-62, 2010 Jul.
Article En | MEDLINE | ID: mdl-20028442

Tattoos are common phenomena in the western world and the demand for their removal has become widespread in the recent years. The introduction of quality-switched lasers has provided an effective removal method that is increasingly being exploited by tattoo studios themselves. Dermatologists, however, are frequently confronted with complications and side effects of tattoo removals that were performed by non-professionals. The objective of this study is to assess potential risks and pitfalls of laser tattoo removal when performed by medical laymen. The methods followed are systematic and evidence-based review of the literature. Four major problem areas were identified: rare but potentially severe allergic or toxic effects of decomposition products of the tattoo pigments; bodily harm caused by out-of-specification usage of the laser devices; malignant disease that is obscured within the area of a tattoo and requires meticulous dermatological diagnosis; and insufficient pre-operative consultation of patients about the risks, side effects and realistic expectations on the therapeutic outcome. We came to a conclusion that tattoo laser removal by medical laymen is unacceptable from the point of view of patient safety and the laws need to ban this practice swiftly.


Forensic Medicine , Tattooing , Humans , Laser Therapy/adverse effects
4.
Toxicol Lett ; 147(1): 35-43, 2004 Feb 28.
Article En | MEDLINE | ID: mdl-14700526

Genotoxic combination effects of oxidative stress (induced by H2O2) and eight nongenotoxic environmental chemicals (4-chloroaniline, 2,3,4,6-tetrachlorophenol, lindane, 2,4-dichloroacetic acid (2,4-D), m-xylene, glyphosate, nitrilotriacetic acid and n-hexanol) were determined in human fibroblasts. Genotoxicity was measured quantitatively by the single cell gel electrophoresis assay. The nongenotoxic chemicals were used in non cytotoxic concentrations. H2O2 was used in concentrations producing low (50 microM) and no cytotoxicity (40 microM). All environmental chemicals acted in a synergistic way with H2O2 except DMSO which effectively inhibited H2O(2)-induced DNA damage. The most effective enhancers were 4-chloroaniline, 2,3,4,6-tetrachlorophenol, m-xylene, and n-hexanol. Synergistic effects of hexanol/H2O2 were still evident at a concentration of 0.09 noec (no observed effect concentration). In contrast to synergistic DNA damage in the cell antagonism was found measuring DNA breakage in isolated PM2 DNA. From the results we concluded that synergisms between H2O2 and nongenotoxic chemicals may be a general phenomenon which is not observed on the level of isolated DNA.


DNA Damage , Environmental Pollutants/toxicity , Fibroblasts/drug effects , Hydrogen Peroxide/toxicity , Mutagens/toxicity , Oxidative Stress , Cell Line , Cell Survival/drug effects , Comet Assay , Dose-Response Relationship, Drug , Drug Synergism , Fibroblasts/metabolism , Humans
5.
Onkologie ; 24 Suppl 1: 49-58, 2001 Feb.
Article De | MEDLINE | ID: mdl-11441311

BACKGROUND: Long-term results are needed to evaluate chemotherapy regimens and prognostic factors in non-Hodgkin's lymphomas (NHL). We report the 10-year follow-up data of aggressive NHL classified according to the Kiel classification and treated with MACOP-B. PATIENTS AND METHODS: Between 1985 and 1991, 71 patients with aggressive NHL were treated in a single institution with MACOP-B and adjuvant radiotherapy as first-line therapy. NHL subtypes were classified according to the updated Kiel classification. Follow-up data were available until 1998. RESULTS: The overall survival (OS) at 10 years is 45% (confidence interval 33-57%), the progression-free survival 42% (30-54%), and the relapse-free survival of the 59 patients (82%) in complete remission is 52% (39-65%). The Kiel classification combined with the International Prognostic Index (IPI) identified diffuse large B-cell and anaplastic large T-cell lymphomas with IPI 0-2 as subgroups with very favorable prognosis after MACOP-B (OS 84% and 80% at 10 years). Late relapses (>2 years after therapy) did occur in these patients but had a good prognosis after second remission. Only 3 of 24 relapses were in the radiation field. Three patients died of toxicity, 1 during MACOP-B (1.3%). Risk factors for therapy-related death were age and pulmonary toxicity. Most patients suffered from chemotherapy-associated mucositis. Osteoporosis was a common late toxicity (39%). Three second cancers but no leukemias or myelodysplastic syndromes were observed during follow-up. CONCLUSIONS: MACOP-B in combination with adjuvant radiotherapy is highly effective in diffuse large B-cell or anaplastic large T-cell-lymphomas with IPI 0-2. Patients with IPI >2 or with centrocytic or secondary centroblastic B-cell or non-anaplastic T-cell lymphomas need more intensive therapy or novel approaches. Regarding the toxicity profile, MACOP-B should be replaced by VACOP-B.


Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Lymphoma, B-Cell/drug therapy , Lymphoma, T-Cell/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bleomycin/administration & dosage , Bleomycin/adverse effects , Combined Modality Therapy , Cyclophosphamide/administration & dosage , Cyclophosphamide/adverse effects , Disease-Free Survival , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Female , Follow-Up Studies , Humans , Leucovorin/administration & dosage , Leucovorin/adverse effects , Lymphoma, B-Cell/mortality , Lymphoma, B-Cell/pathology , Lymphoma, B-Cell/radiotherapy , Lymphoma, T-Cell/mortality , Lymphoma, T-Cell/pathology , Lymphoma, T-Cell/radiotherapy , Male , Methotrexate/administration & dosage , Methotrexate/adverse effects , Middle Aged , Neoplasm Staging , Prednisone/administration & dosage , Prednisone/adverse effects , Radiotherapy, Adjuvant , Retrospective Studies , Survival Rate , Vincristine/administration & dosage , Vincristine/adverse effects
8.
Anesth Analg ; 92(1): 112-7, 2001 Jan.
Article En | MEDLINE | ID: mdl-11133611

UNLABELLED: Supplemental oxygen maintained during and for 2 h after colon resection halves the incidence of nausea and vomiting. Whether supplemental oxygen restricted to the intraoperative period is sufficient remains unknown. Similarly, the relative efficacy of supplemental oxygen and ondansetron is unknown. We tested the hypothesis that intraoperative supplemental oxygen reduces the incidence of postoperative nausea and vomiting. Patients (n = 240) undergoing gynecological laparoscopy were given a standardized isoflurane anesthetic. After induction, they were randomly assigned to the following three groups: routine oxygen administration with 30% oxygen, balance nitrogen (30% Oxygen group), supplemental oxygen administration with 80% oxygen, balance nitrogen (80% Oxygen group), and Ondansetron 8 mg (immediately after induction), combined with 30% oxygen, balance nitrogen (Ondansetron group). The overall incidence of nausea and/or vomiting during the initial 24 postoperative h was 44% in the patients assigned to 30% oxygen and 30% in the Ondansetron group, but only 22% in those given 80% oxygen. The incidence was thus halved by supplemental oxygen and was significantly less than with 30% oxygen. There were, however, no significant differences between the 30% oxygen and ondansetron groups, or between the ondansetron and 80% oxygen groups. We conclude that supplemental oxygen effectively prevents postoperative nausea and vomiting after gynecological laparoscopic surgery; furthermore, ondansetron is no more effective than supplemental oxygen. IMPLICATIONS: Supplemental oxygen reduces the risk of postoperative nausea and vomiting (PONV) as well or better than 8 mg of ondansetron. Because oxygen is inexpensive and essentially risk-free, supplemental oxygen is a preferable method of reducing PONV.


Antiemetics/therapeutic use , Ondansetron/therapeutic use , Oxygen/administration & dosage , Postoperative Nausea and Vomiting/prevention & control , Serotonin Antagonists/therapeutic use , Adult , Dose-Response Relationship, Drug , Drinking , Eating , Female , Gynecologic Surgical Procedures/adverse effects , Humans , Intraoperative Care , Laparoscopy/adverse effects , Multivariate Analysis
9.
Spat Vis ; 13(2-3): 201-14, 2000.
Article En | MEDLINE | ID: mdl-11198232

Based on an information theoretical approach, we investigate feature selection processes in saccadic object and scene analysis. Saccadic eye movements of human observers are recorded for a variety of natural and artificial test images. These experimental data are used for a statistical evaluation of the fixated image regions. Analysis of second-order statistics indicates that regions with higher spatial variance have a higher probability to be fixated, but no significant differences beyond these variance effects could be found at the level of power spectra. By contrast, an investigation with higher-order statistics, as reflected in the bispectral density, yielded clear structural differences between the image regions selected by saccadic eye movements as opposed to regions selected by a random process. These results indicate that nonredundant, intrinsically two-dimensional image features like curved lines and edges, occlusions, isolated spots, etc. play an important role in the saccadic selection process which must be integrated with top-down knowledge to fully predict object and scene analysis by human observers.


Data Interpretation, Statistical , Motion Perception/physiology , Pattern Recognition, Visual/physiology , Saccades/physiology , Adult , Computer Simulation , Fixation, Ocular/physiology , Humans , Image Processing, Computer-Assisted , Reference Values , Video Recording
10.
Free Radic Res ; 29(1): 25-34, 1998 Jul.
Article En | MEDLINE | ID: mdl-9733019

The isomers n- and iso-butyraldehyde (BuA) in combination with Cu(II) induced single and double strand breaks in PM2 DNA, whereas the aldehydes, or Cu(II) alone had only negligible effect. The DNA damage was the result of radical oxidations of the aldehydes under formation of Cu(I). Cu(I) formation was independent of molecular oxygen. Extensive DNA degradation was only observed in the presence of molecular oxygen. Characterization of DNA damage pointed to different ultimate DNA damaging species. While catalase and neocuproine inhibited strand break formation induced by iso-BuA/Cu(II) to a high degree, these inhibitors were less effective in the n-BuA/Cu(II) reaction. On the other hand, sodium azide showed a high strand break inhibition in the n-BuA/Cu(II) reaction, but low inhibition in the iso-BuA/Cu(II) reaction. 2-Deoxyguanosine was hydroxylated in the 8-position by iso-BuA/Cu(II) but little reaction occurred with n-BuA/Cu(II). Chemiluminescence was detected during both BuA/Cu(II) reactions, whereby the intensity of the luminescence signal was 3.5-fold higher for n-BuA/Cu(II) than for iso-BuA/Cu(II). We suppose that the copper(II)-driven oxidation of n- and iso-BuA proceeds via different pathways with different DNA damaging consequences. Whereas the oxidation of iso-BuA mainly results in damage by .OH-radicals, the oxidation of n-BuA may lead to a radical reaction chain whereby excited states are involved and the resulting DNA-damaging species are not .OH-radicals.


Aldehydes/chemistry , Copper/chemistry , DNA Damage/drug effects , 8-Hydroxy-2'-Deoxyguanosine , Aldehydes/metabolism , Aldehydes/pharmacology , Copper/metabolism , Copper/pharmacology , DNA/chemistry , DNA/drug effects , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/chemistry , Deoxyguanosine/metabolism , Oxidation-Reduction
11.
Toxicol Lett ; 94(3): 159-66, 1998 Feb.
Article En | MEDLINE | ID: mdl-9609318

Malondialdehyde (MDA) is a product of lipid peroxidation (LPO). In combination with CuCl2 MDA induced single strand breaks in PM2 DNA whereas MDA or CuCl2 alone had no effect. Cu(II) oxidized MDA by a radical mechanism under formation of Cu(I). DNA strand break induction was inhibited by catalase (98%), neocuproine (76%) and DMSO (61%). The synergistic damaging effect of MDA and Cu(II) was also demonstrated in human fibroblasts measured by alkaline elution. The combination MDA/CuCl2 caused extensive DNA breakage while neither MDA nor CuCl2 alone induced DNA damage within the cell. Synergistic cytotoxic effects were observed 18 h after a simultaneous treatment of the cells with MDA and CuCl2 for 1 h.


Copper/toxicity , DNA Damage , DNA, Single-Stranded/drug effects , DNA, Viral/drug effects , Fibroblasts/drug effects , Malondialdehyde/toxicity , Administration, Topical , Anti-Inflammatory Agents/pharmacology , Bacteriophages/genetics , Cell Survival , Cells, Cultured , Chelating Agents/pharmacology , Copper/analysis , Dimethyl Sulfoxide/pharmacology , Drug Synergism , Humans , Phenanthrolines/pharmacology
12.
Neurosci Lett ; 228(3): 155-8, 1997 Jun 13.
Article En | MEDLINE | ID: mdl-9218631

Orientation selectivity is a basic property of neurones in the visual cortex of higher vertebrates. Such neurones can be seen to act as 'feature detectors', which provide an efficient cortical representation of the outside world. More recently, the removal of correlations between the signals of cortical neurones has been suggested as suitable theoretical concept for explaining the development of receptive fields. Corresponding neural network simulations yielded oriented 'receptive field' structures resembling those observed by neurophysiologists. The findings suggest that the 'decorrelation approach' can provide a causal relationship between characteristics of the physical world and brain function. However, we were able to reveal a basic deficit of the decorrelation approach which we illustrate by the construction of two artificial 'worlds', a 'Gaussian' one and an 'orientation-only' one. We show that, according to the decorrelation approach, oriented environmental features would be neither necessary nor sufficient for the development of oriented receptive fields. Thus the link between environmental structure and cortical orientation selectivity still awaits a theoretical explanation.


Neural Networks, Computer , Orientation/physiology , Visual Cortex/physiology , Environment , Image Processing, Computer-Assisted , Models, Neurological , Visual Fields
13.
Spat Vis ; 11(1): 107-15, 1997.
Article En | MEDLINE | ID: mdl-9304760

IPRS is a freely available software system which consists of about 250 library functions in C, and a set of application programs. It is designed to run under UNIX and comes with full source code, system manual pages, and a comprehensive user's and programmer's guide. It is intended for use by researchers in human vision, pattern recognition, image processing, machine vision and machine learning.


Image Processing, Computer-Assisted/methods , Pattern Recognition, Visual , Software , Humans , Microcomputers
14.
Bone Marrow Transplant ; 20(9): 787-8, 1997 Nov.
Article En | MEDLINE | ID: mdl-9384483

We report a case of metastatic gastrointestinal leiomyosarcoma treated with high-dose combination chemotherapy and autologous peripheral blood stem cell transplantation. After incomplete surgical resection, enteral, peritoneal and hepatic involvement remained. Postoperatively, standard-dose chemotherapy with etoposide, ifosfamide, cisplatin and epirubicine, and high-dose chemotherapy with the same agents (carboplatin replacing cisplatin) was given. Treatment was well tolerated and the patient remains in complete remission at 36+ months. We conclude that high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation may be of use as treatment for inoperable residual disease after resection of the primary lesion in gastrointestinal and other soft tissue sarcomas.


Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hematopoietic Stem Cell Transplantation , Leiomyosarcoma/therapy , Stomach Neoplasms/therapy , Adult , Carboplatin/therapeutic use , Combined Modality Therapy , Epirubicin/therapeutic use , Etoposide/therapeutic use , Female , Humans , Ifosfamide/therapeutic use , Leiomyosarcoma/pathology , Stomach Neoplasms/pathology
16.
Free Radic Res ; 24(5): 325-32, 1996 May.
Article En | MEDLINE | ID: mdl-8733936

The aliphatic n-butyr-and n-valeraldehyde as well as the aromatic benz- and anisaldehyde induced DNA strand breaks in PM2 DNA in the presence of CuCl2. Neither aldehydes nor CuCl2 alone showed DNA breakage properties. The maximum of single strand breaks (SSBs) induced by the combination of CuCl2 and aldehydes was dependent on the CuCl2-concentration. The aliphatic aldehydes induced SSBs and double strand breaks (DSBs) at lower concentrations than aromatic aldehydes when optimal CuCl2 concentration were used. Catalase and neocuproine nearly completely inhibited strand break formation induced by aromatic aldehydes/CuCl2. The prevention of strand breaks induced by aliphatic aldehydes/CuCl2 was less effective. While the inhibition by neocuproine was only 25%, catalase was totally ineffective. In all aldehydes/CuCl2 mixtures the formation of Cu(I) was observed. The results point to different DNA damaging species produced during redox reactions of aromatic and aliphatic aldehydes in combination with CuCl2.


Aldehydes/toxicity , Benzaldehydes/toxicity , Copper/pharmacology , DNA Damage , DNA, Viral/drug effects , Mutagens/toxicity , Molecular Structure , Reactive Oxygen Species/metabolism
17.
IEEE Trans Image Process ; 5(6): 1026-42, 1996.
Article En | MEDLINE | ID: mdl-18285189

Local intrinsic dimensionality is shown to be an elementary structural property of multidimensional signals that cannot be evaluated using linear filters. We derive a class of polynomial operators for the detection of intrinsically 2-D image features like curved edges and lines, junctions, line ends, etc. Although it is a deterministic concept, intrinsic dimensionality is closely related to signal redundancy since it measures how many of the degrees of freedom provided by a signal domain are in fact used by an actual signal. Furthermore, there is an intimate connection to multidimensional surface geometry and to the concept of ;Gaussian curvature'. Nonlinear operators are inevitably required for the processing of intrinsic dimensionality since linear operators are, by the superposition principle, restricted to OR-combinations of their intrinsically 1-D eigenfunctions. The essential new feature provided by polynomial operators is their potential to act on multiplicative relations between frequency components. Therefore, such operators can provide the AND-combination of complex exponentials, which is required for the exploitation of intrinsic dimensionality. Using frequency design methods, we obtain a generalized class of quadratic Volterra operators that are selective to intrinsically 2-D signals. These operators can be adapted to the requirements of the signal processing task. For example, one can control the "curvature tuning" by adjusting the width of the stopband for intrinsically 1-D signals, or the operators can be provided in isotropic and in orientation-selective versions. We first derive the quadratic Volterra kernel involved in the computation of Gaussian curvature and then present examples of operators with other arrangements of stop and passbands. Some of the resulting operators show a close relationship to the end-stopped and dot-responsive neurons of the mammalian visual cortex.

19.
Blood ; 85(9): 2482-9, 1995 May 01.
Article En | MEDLINE | ID: mdl-7537116

We explored the ex vivo alteration in the cytokine release of stimulated blood taken from healthy volunteers treated subcutaneously with 480 micrograms granulocyte colony-stimulating factor (G-CSF). In a double-blind, controlled, randomized study with 21 volunteers who received G-CSF once or twice 24 hours apart, we measured lipopolysaccharide (LPS)-inducible release of various cytokines and soluble receptors at different times after treatment. At day 1 after a single dose of G-CSF, mediator release was also initiated with muramyl dipeptide, Staphylococcus aureus enterotoxin A, lipoteichoic acid, streptolysin O, complement factor C5a, phytohemagglutinin, or phorbol myristate acetate. In blood from G-CSF-treated subjects, our major findings were (1) a maximal 12-fold increase in interleukin-1 receptor antagonist (IL-1ra) release and an increase of both the p55 and p75 soluble tumor necrosis factor (TNF) receptors; (2) a reduction in TNF release when using all the various stimuli described except LPS; (3) an increase in G-CSF and, to lesser extent, in IL-6, IL-8, and IL-10 release; and (4) an attenuation of interferon-gamma (IFN-gamma) and granulocyte-macrophage (GM)-CSF release. Our findings demonstrate that the major effect of G-CSF treatment is a change in the responsiveness of blood towards a variety of stimuli, which we interpret as a shift toward an antiinflammatory cytokine response.


Cytokines/metabolism , Granulocyte Colony-Stimulating Factor/pharmacology , Leukocytes, Mononuclear/drug effects , Acetylmuramyl-Alanyl-Isoglutamine/pharmacology , Adult , Cytokines/blood , Double-Blind Method , Enterotoxins/pharmacology , Female , Granulocyte Colony-Stimulating Factor/administration & dosage , Humans , Leukocyte Count/drug effects , Leukocytes, Mononuclear/metabolism , Lipopolysaccharides/pharmacology , Lymphocyte Activation/drug effects , Male , Teichoic Acids/pharmacology
20.
Toxicol In Vitro ; 9(5): 751-6, 1995 Oct.
Article En | MEDLINE | ID: mdl-20650153

A cytotoxicity assay to determine growth inhibition after a 1-hr treatment with xenobiotics in serum-free medium and subsequent re-incubation in serum-containing medium without test chemicals was characterized and optimized for cytotoxicity screening. Our results indicated that after treatment of human fibroblasts with the test chemicals a 44-hr re-incubation period is most suitable for measuring the growth inhibitory effects of a broad spectrum of chemicals. Applying the assay, the activity to inhibit growth by 10% (log IC(10)) correlated with the lipophilicity (specified as octanol-water partition coefficient = log K(ow)) of 19 xenobiotics. The linear regression coefficient was r = 0.91. This close correlation between toxicity and lipophilicity shows that the test, which avoids long-term incubation in serum-containing medium, is suitable for cytotoxicity screening and structure-activity analysis.

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