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2.
Rev Sci Instrum ; 91(8): 083503, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-32872937

ABSTRACT

Coated glass targets are a key component of the Wendelstein 7-X laser blow-off system that is used for impurity transport studies. The preparation and analysis of these glass targets as well as their performance is examined in this paper. The glass targets have a high laser damage threshold and are coated via physical vapor deposition with µm thick films. In addition, nm-thin layers of Ti are used as an interface layer for improved ablation efficiency and reduced coating stress. Hence, the metallic or ceramic coating has a lateral homogeneity within 2% and contaminants less than 5%, being optimal for laser ablation processing. With this method, a short (few ms) and well defined pulse of impurities with about 1017 particles can be injected close to the last closed flux surface of Wendelstein 7-X. In particular, a significant amount of atoms with a velocity of about 1 km/s enters the plasma within 1 ms. The atoms are followed by a negligible concentration of slower clusters and macro-particles. This qualifies the use of the targets and applied laser settings for impurity transport studies with the laser blow-off system in Wendelstein 7-X.

3.
Vox Sang ; 112(6): 586-594, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28809049

ABSTRACT

BACKGROUND AND OBJECTIVES: The Spectra Optia® continuous mononuclear cell (CMNC apheresis) system has emerged as the preferred device in peripheral blood stem cell collections over the original two-step Spectra Optia® mononuclear cell (MNC apheresis) system. Until now, no comparative data were available for non-stimulated MNC collections that are required for immunotherapy. MATERIALS AND METHODS: We compared collection parameters and product composition for Spectra Optia MNC- as well as CMNC-apheresis systems in non-stimulated MNC collections from 35 registry donors intended for donor lymphocyte infusions. In a subsequent analysis, different centrifugation forces (determined as packing factor or PF) were investigated regarding target cell yield and contamination in 61 collections using the CMNC device only. RESULTS: Comparable collection efficiencies as well as target cell yields could be achieved with the Spectra Optia MNC- versus CMNC program. Similar numbers of MNC, T, B and NK cells could be collected with both devices. This led to a more than twofold lymphocyte recruitment from lymphatic tissue into the blood during apheresis. However, significantly more blood had to be processed with longer procedure time using the MNC program resulting in larger product volumes compared to the CMNC setting. Red blood cell and platelet (PLT) contamination were similar. Lowering the centrifugation force from PF4·5 to PF4·0 significantly reduced PLT contamination without affecting target cell yield in the product. CONCLUSION: The Spectra Optia® CMNC device using lower centrifugal force (PF4·0) showed similar target cell yield and composition as well as collection efficiencies with superior performance parameters and lower PLT contamination compared to the MNC setting.


Subject(s)
Leukapheresis/instrumentation , Leukocytes, Mononuclear , Blood Donors , Blood Platelets , Centrifugation , Erythrocytes , Humans , Immunotherapy , Leukapheresis/methods , Lymphocytes , Pilot Projects , Prospective Studies , Thrombocytopenia
4.
Eur Cell Mater ; 29: 177-88; discussion 188-9, 2015 Mar 04.
Article in English | MEDLINE | ID: mdl-25738585

ABSTRACT

Bone diseases such as osteoporosis, osteoarthritis and rheumatoid arthritis, impinge on the performance of orthopaedic implants by impairing bone regeneration. For this reason, the development of effective surface modifications supporting the ingrowth of implants in morbid bone tissue is essential. Our study is designed to elucidate if cells with restricted cell-function limiting adhesion processes benefit from plasma polymer deposition on titanium. We used the actin filament disrupting agent cytochalasin D (CD) as an experimental model for cells with impaired actin cytoskeleton. Indeed, the cell's capacity to adhere and spread was drastically reduced due to shortened actin filaments and vinculin contacts that were smaller. The coating of titanium with a positively charged nanolayer of plasma polymerised allylamine (PPAAm) abrogated these disadvantages in cell adhesion and the CD-treated osteoblasts were able to spread significantly. Interestingly, PPAAm increased spreading by causing enhanced vinculin number and contact length, but without significantly reorganising actin filaments. PPAAm with the monomer allylamine was deposited in a microwave-excited low-pressure plasma-processing reactor. Cell physiology was monitored by flow cytometry and confocal laser scanning microscopy, and the length and number of actin filaments was quantified by mathematical image processing. We showed that biomaterial surface modification with PPAAm could be beneficial even for osteoblasts with impaired cytoskeleton components. These insights into in vitro conditions may be used for the evaluation of future strategies to design implants for morbid bone tissue.


Subject(s)
Allylamine/pharmacology , Coated Materials, Biocompatible/pharmacology , Osteoblasts/drug effects , Polymers/pharmacology , Actin Cytoskeleton/drug effects , Actin Cytoskeleton/metabolism , Allylamine/chemistry , Cell Adhesion/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Coated Materials, Biocompatible/chemistry , Cytochalasin D/pharmacology , Humans , Microscopy, Confocal , Nucleic Acid Synthesis Inhibitors/pharmacology , Osteoblasts/metabolism , Polymers/chemistry , Surface Properties/drug effects , Titanium/chemistry , Vinculin/metabolism
5.
Anal Bioanal Chem ; 374(4): 720-3, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12397501

ABSTRACT

The oxidation of thin aluminium layers in a microwave plasma has been investigated to determine the kinetics of oxide growth. Thin Al-coatings were oxidized by means of a variety of gas mixtures, characterized by different partial pressures of oxygen, in microwave-induced plasmas of different power. To study the whole kinetic process the Al-metal and the oxide formed were investigated by means of a combination of grazing incidence X-ray reflectometry (GIXR) and grazing incidence X-ray diffractometry (GIXRD). XPS and FTIR spectroscopy confirmed the formation of stoichiometric Al(2)O(3). The alumina formed is X-ray amorphous. Quantitative description of oxide formation was achieved indirectly by determination of the decrease in the integrated intensity of the Al(111)-peak and the total thickness of the whole coating. These values enabled calculation of kinetic data. It was found that oxide growth was a combination of two simultaneous processes - diffusion and sputter processes. The diffusion coefficient D (cm(2) s(-1)) and the sputter rate S (nm s(-1)) were determined. The effect of the composition of the gas mixture, microwave power, and concentration of activated oxygen species on the oxidation process will be discussed. For calculation of the activation energy, E(A), of this plasma-enhanced diffusion process the temperature-dependence of D was investigated.

6.
Exp Dermatol ; 9(4): 248-51, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10949545

ABSTRACT

Cytokines are of major importance for the pathogenesis of cutaneous T-cell lymphomas (CTCL). Recent data suggested that IL-15 and IL-16 are survival/growth factors for the malignant T cells in these entities. To investigate the expression of IL-15 and IL-16 in mycosis fungoides (MF) and CD30+ pleomorphic T-cell lymphoma in vivo, we established a competitive RT-PCR technique. Analyzing skin biopsies from CTCL patients at different stages in comparison to psoriatic and healthy skin, we found IL-15 and IL-16 mRNA overexpression in both CTCL entities. Remarkably, there was some evidence for a stage-dependent increase during MF progression. We found only slight overexpression in early stage MF, when only few tumor cells are detectable within the infiltrates, whereas marked overexpression was found in more advanced lesions, which are characterized by a higher density of malignant cells. These results suggested that CTCL cells themselves might produce the cytokines. To further elucidate this hypothesis, two CTCL cell lines were analyzed but gave conflicting results. Therefore, the cellular origin of the IL-15 and IL-16 overexpression in CTCL remains unclear. Considering the significant overexpression of IL-15 and IL-16 and their biological capacities it is likely that these cytokines contribute to the tumor development. So, they might be involved in growth and skin homing of CTCL cells.


Subject(s)
Interleukin-15/metabolism , Interleukin-16/metabolism , Lymphoma, T-Cell, Cutaneous/immunology , Skin Neoplasms/immunology , Adult , Base Sequence , Case-Control Studies , DNA Primers/genetics , Gene Expression , Humans , Interleukin-15/genetics , Interleukin-16/genetics , Ki-1 Antigen/metabolism , Lymphoma, T-Cell, Cutaneous/etiology , Lymphoma, T-Cell, Cutaneous/pathology , Mycosis Fungoides/immunology , Psoriasis/immunology , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , Skin Neoplasms/etiology , Skin Neoplasms/pathology
7.
Arch Dermatol Res ; 292(4): 164-72, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10836609

ABSTRACT

IL-10 is a promising candidate for the treatment of cutaneous disorders. Antipsoriatic efficacy of systemic IL-10 treatment has been already demonstrated. This includes histomorphological changes in the epidermis, suggesting effects on keratinocytes. However, less is known about direct effects of IL-10 on this cell population, although effects are likely since IL-10 receptor expression on keratinocytes has been demonstrated recently. Therefore we analysed the effects of IL-10 on keratinocytes in vitro, using concentrations of human recombinant IL-10 corresponding to those detectable in plasma during therapy. Proliferation, cytokine formation (IL-6, IL-8, IL-1ra), and expression of surface molecules (MHC class I and II, costimulatory molecules CD80 and CD86, CD29, CD54, CD95) were measured in stimulated and unstimulated cells. Although stimulation influenced the expression levels of certain surface markers, no or only slight effects of IL-10 were found. In contrast considerable inhibitory effects of IL-10 on surface molecule expression and cytokine secretion by peripheral blood human monocytes were observed. Our results suggest that the antipsoriatic activity of IL-10 is rather caused by modulatory effects on circulating immune cells, which subsequently might infiltrate the skin, than by direct effects on human keratinocytes. Considering the remarkable antipsoriatic activity of IL-10 and the observation that IL-10 seem to act on peripheral blood mononuclear cells but not on keratinocytes provide further evidence that circulating immune cells play a key role in the pathology of psoriasis. Finally, our results argue against the value of IL-10 therapy in dermatoses strictly limited to keratinocyte involvement.


Subject(s)
Interleukin-10/pharmacology , Keratinocytes/drug effects , Antigens, CD/analysis , B7-1 Antigen/analysis , B7-2 Antigen , Cell Division/drug effects , Cells, Cultured , Cytokines/analysis , Dose-Response Relationship, Drug , HLA Antigens/analysis , Humans , Integrin beta1/analysis , Intercellular Adhesion Molecule-1/analysis , Keratinocytes/immunology , Membrane Glycoproteins/analysis , Monocytes/drug effects , Monocytes/immunology , Psoriasis/blood , Psoriasis/drug therapy , Psoriasis/immunology , Recombinant Proteins/pharmacology
8.
Exp Dermatol ; 9(1): 71-6, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10688378

ABSTRACT

Physiologically, B-lymphocytes are not present in the skin. Even in pathological situations they rarely occur. In contrast, primary cutaneous B-cell lymphomas (CBCL) are characterized by proliferation of B lymphocytes within the skin. This suggests the existence of a certain microenvironment supporting homing and expansion of clonal B cells. Cytokines were demonstrated to be involved in the pathogenesis of cutaneous lymphomas of T-cell origin. Cytokine expression in cutaneous B-cell lymphoma lesions, however, has not been investigated so far. Therefore, the mRNA level of several cytokines was analyzed in biopsies from 7 patients with CBCL and compared to pleomorphic T-cell lymphoma (n = 6), psoriasis (n = 9), and healthy skin (n = 7), using a competitive RT-PCR approach. An overexpression of TNF-alpha, IL-10, and IL-6 was found. Enhanced IL-8 mRNA expression was detected in 2/7 cases. The overexpression of IL-6 and IL-10 in CBCL might be of particular importance, since these cytokines are considered to support B-cell growth. Additionally, the overexpression of IL-10 may contribute to tumor progression since this immunosuppressive cytokine might be involved in downregulation of immunological tumor surveillance, in part by inhibiting type 1 cytokine formation. In fact, we did not detect IFN-gamma and IL-2 expression. Taken together, we found a cytokine pattern in CBCL lesions which might contribute to tumor B-cell growth.


Subject(s)
Cytokines/genetics , Lymphoma, B-Cell/immunology , Skin Neoplasms/immunology , Adult , Gene Expression , Humans , Immunohistochemistry , Inflammation Mediators/metabolism , Interleukin-10/genetics , Interleukin-6/genetics , Interleukin-8/genetics , Lymphoma, B-Cell/genetics , Lymphoma, B-Cell/pathology , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Tumor Necrosis Factor-alpha/genetics
9.
Geburtshilfe Frauenheilkd ; 53(2): 105-7, 1993 Feb.
Article in German | MEDLINE | ID: mdl-8385048

ABSTRACT

A pregnant woman with post-term birth developed a varicella rash on the day, when birth was to be initiated. The date was then postponed, until varicella zoster virus (VZV) IgG-antibodies could be proved in the mother, so as to allow the child to achieve an adequate diaplacental passive immunisation. Cesarean section was performed on the 7th day after the rash, but a comparison of the child's blood (from the umbilical cord) with the mother's blood showed, that the VZV antibodies developed by the mother during this time were only present in a tenfold reduced amount in the child. Antibodies to herpes simplex virus, already present in the mother's blood before the VZV infection, also increased because of the close relationship of the virus to VZV. Similar to the VZV antibodies, these antibodies did not increase in the baby as in the mother. Our results show that maternal antibodies are not transferred rapidly to the baby, and therefore it seems reasonable, that in the case of chickenpox at the time of delivery, the birth should be delayed, not only until seroconversion in the mother's blood, but - if possible - a few days longer.


Subject(s)
Antibodies, Viral/analysis , Chickenpox/immunology , Herpesvirus 3, Human/immunology , Immunity, Maternally-Acquired/immunology , Maternal-Fetal Exchange/physiology , Pregnancy Complications, Infectious/immunology , Adult , Cesarean Section , Female , Humans , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Infant, Newborn , Male , Pregnancy , Pregnancy Trimester, Third , Pregnancy, Prolonged/immunology , Reoperation
10.
Acta Endocrinol (Copenh) ; 128(1): 24-8, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8447191

ABSTRACT

Urinary GH excretion reflects average plasma levels. Using a highly sensitive sandwich enzyme immunoassay we determined GH concentrations in the 24 h accumulated urine samples of 54 healthy persons (aged 1.5-90 years), 8 acromegalic patients, 4 acromegalic patients after enucleation of a GH-producing adenoma, 8 patients with partial hypopituitarism and in first morning urine and 12 h accumulated daytime urine of 4 healthy children and 3 children with growth failure. GH secretion is age-dependent, with high rates between ages 1 and 20 (ages 0-20 years: 10.4 ng/g creatinine +/- 6.3 vs age > 20-75 years: 3.1 ng/g creatinine +/- 1.6). An age-dependent increase in urinary GH is found in the pubertal age group (10 ng/24 h +/- 6.8 vs prepubertal group: 4.6 ng/24 h +/- 2.95). GH excretion of patients with acromegaly differs significantly from healthy subjects (72 ng/24 h +/- 49 vs 3.9 ng/24 h +/- 2.3). After a successful operation, acromegalic patients do not differ from the collective norm. Six of 8 patients with partial hypopituitarism show lower GH concentrations in urine than healthy subjects (1.2 ng/l +/- 0.2 vs 2.6 ng/l +/- 1.2), but daily GH output does not differ, since significantly more urine is then excreted. At night, healthy children secrete significantly more GH than during the day (night: 0.16 ng.kg-1 x (12 h)-1 +/- 0.02 vs day: 0.07 ng.kg-1 x (12 h)-1 +/- 0.03), while output is the same for GH-deficient children. Both groups have similar GH daytime output, but GH-deficient children have significantly less nocturnal output.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Acromegaly/urine , Dwarfism/urine , Growth Hormone/urine , Hypopituitarism/urine , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Circadian Rhythm , Diuresis , Female , Humans , Immunoenzyme Techniques , Infant , Male , Middle Aged , Radioimmunoassay , Regression Analysis , Sex Factors
11.
Clin Investig ; 70(5): 396-402, 1992 May.
Article in English | MEDLINE | ID: mdl-1600349

ABSTRACT

Endocrine functions were examined in 21 patients with mitochondrial myopathies presenting with chronic progressive external ophthalmoplegia and other additional neurological and multisystemic symptoms. Ten patients had the features of the Kearns-Sayre syndrome. Deletions of the mitochondrial DNA were found in 4 out of 5 patients examined. Fourteen patients, including 3 with deletions of the mitochondrial DNA, had various and often multiple endocrine abnormalities: 6 patients were of short stature, 3 had irregular menstrual cycles, 3 had undersized testicles, 5 showed an insufficient rise of growth hormone following the administration of growth-hormone-releasing hormone, 4 showed an insufficient rise in FSH after administration of gonadotropin-releasing hormone, 5 had manifest diabetes mellitus, 3 showed an impaired glucose tolerance, and 2 patients had subnormal serum levels of parathormone in combination with hypocalcaemia. One patient additionally had Klinefelter's syndrome with a kariotype 47, XXY and increased levels of FSH and LH, subnormal levels of testosterone and subnormal testicular volume. The occurrence of endocrine defects correlated with the duration of disease. The data demonstrate that endocrine abnormalities are frequently associated with mitochondrial myopathy, indicating that this multisystemic disease also involves various endocrine tissues.


Subject(s)
Endocrine Glands/physiopathology , Mitochondria, Muscle/ultrastructure , Neuromuscular Diseases/physiopathology , Ophthalmoplegia/physiopathology , Adult , Calcium/metabolism , Dwarfism/physiopathology , Female , Glucose/metabolism , Hormones/analysis , Humans , Hypogonadism/physiopathology , Kearns-Sayre Syndrome/physiopathology , Male , Middle Aged , Neuromuscular Diseases/pathology , Pituitary Function Tests
12.
Horm Res ; 37(4-5): 171-5, 1992.
Article in English | MEDLINE | ID: mdl-1490659

ABSTRACT

For several years, it has been possible to determine renin by a direct RIA. In the present study, plasma active renin concentration (PRC) was related to plasma renin activity (PRA) and aldosterone as a function of a standardized posture test. Using PRC, our target was to define the shortest necessary test duration. The three parameters were examined in 10 healthy male subjects (22-34 years old). Salt balance was determined in 24-hour urine, and plasma potassium and sodium were measured. Volunteers were hospitalized for 1 night, and at 8 a.m. the next morning they were subjected to the following postural changes: 3 h active orthostasis and 3 h recumbency. Frequent blood samples were taken. Orthostasis induced a significant rise in PRC, PRA and aldosterone already after 15 min. PRC and PRA reached a maximum level after 90 min of orthostasis and remained relatively stable, while aldosterone reached its highest level already after 30 min and then gradually decreased. Significant correlations were found between PRA and PRC (p < 0.001), between PRC and aldosterone (p < 0.001), and between PRA and aldosterone (p < 0.001). The PRC/PRA ratio changed during the course of the test, especially in supine subjects. When subjects returned to the supine position, all the parameters measured began a continual decrease. There were no significant changes in serum potassium and sodium levels throughout the duration of the test.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Posture , Renin/blood , Adult , Aldosterone/blood , Humans , Kinetics , Male , Potassium/blood , Potassium/urine , Sodium/blood , Sodium/urine , Supine Position
13.
Acta Biol Med Ger ; 39(6): 671-9, 1980.
Article in German | MEDLINE | ID: mdl-7456930

ABSTRACT

The construction and operation of a measuring device containing an enzyme electrode is described. Glucose oxidase is enclosed in an acrylamide film by means of photopolymerization. The maximal increase of the anodic current of the H2O2 being formed in the enzyme reaction serves as measuring signal. The device gives for diluted serum and blood correlation coefficients above 0,99 according to the methods given in the German Pharmacopeia 7. The measuring time for each specimen is roughly 90 s, the serial variation coefficient 2%.


Subject(s)
Blood Glucose/analysis , Electrodes , Enzymes, Immobilized , Glucose Oxidase , Humans , Penicillium/enzymology
14.
15.
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