Search Results - (Author, Cooperation:T. Moritz)

2014-10-03

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Cell Separation ; *Cell Transplantation ; Cytokine Receptor Common beta Subunit/deficiency/*genetics ; Female ; *Genetic Therapy ; Lung/*cytology/metabolism/pathology ; Macrophages, Alveolar/*metabolism/*transplantation ; Male ; Mice ; Oligonucleotide Array Sequence Analysis ; Phenotype ; Pulmonary Alveolar Proteinosis/genetics/pathology/*therapy ; Time Factors

1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

By application of a recently developed method allowing analysis of gibberellins (GAs) in mg amounts of tissue, the effect of photoperiod on levels of GAs in shoot tips of individual seedlings of the woody species Salix pentandra was studied. In elongating long day-grown seedlings, maximum levels of GA1 were found 5–20 mm below the apex, approximately twice the levels in other segments. After exposure of plants to 5 or 15 short days, the levels of GA1 were about 50% lower within this specific region of the stem, as compared with seedlings grown under long days. Short day-induced cessation of shoot elongation also correlated with overall declines in the levels of GA53, GA19, GA20 and GA8, Within each photoperiodic treatment the levels of these GAs were generally relatively similar throughout the upper 35 mm of stems. No differences in internode lengths or in lengths of pith or epidermal cells were found in plants grown under long days compared with those exposed to 5 short days. In both cases, cells in mitosis were observed in the subapical stem tissues of shoot tips. After 15 short days, stem elongation was completed, and dividing cells were generally not found in the subapical part of the stem. However, short day exposure did not prevent elongation of internodes and cells differentiated before the treatment was started. Thus, the localised decrease in level of GA1 in shoot tips under short days precedes the morphological and anatomical changes connected with the short day-induced cessation of elongation growth. This supports the hypothesised role for GA1 in photoperiodic control of shoot elongation in S. pentandra.

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1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

Extracts of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) shoots were purified by reversed and normal phase HPLC; gibberellin (GA)-like compounds detected by radioimmunoassay with antibodies against GA4 and the Tan-ginbozu dwarf rice micro-drop biossay were analyzed by GC-MS. Three major components were identified as GA4, GA7, and GA9 while smaller amounts of GA1, GA3 and putative GA9-glucosyl ester were also present.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

A potent mitogen for T lymphocytes of various species has recently been isolated from the supernatant of cultured Mycoplasma arthritidis organisms (MAS). In the mouse, reactivity to this mitogen has been observed to be controlled by the I-E subregion of the major histocompatibility complex. We have analysed the responses of spleen cells from several inbred rat strains covering practically all known haplotypes of the major histocompatibility complex of the rat (RT1). Unlike in the mouse, all of these responded well to MAS, except for the BN rat strain, which is a low responder to all T-cell mitogens, including phytohaemagglutinin and concanavalin A. This unresponsiveness, however, appeared to be unrelated to the RT1 haplotype, since LEW.1N rats carrying the same RT1u haplotype as BN animals responded well. Mice of the strain C57BL/6 are non-responders to MAS, but—as previously shown—their spleen cell responses can be reconstituted by the addition of 2-mercaptoethanol. No such reconstitution was observed for the low responsiveness of BN rat spleen cells. Stimulation with MAS induced high titres of interferon (presumably gamma interferon) in spleen cells from all rat strains tested. Spleen cells from BN rats produced lower interferon activities than those from other strains.

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1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

This report succinctly summarizes a number of experiments in which human leucocytes were activated by the mitogen in the supernatant of cultured Mycoplasma arthritidis (MAS). Lymphocytes from a large number of donors were found to be reactive when the two parameters of lymphoproliferation and of production of gamma interferon were analysed. Lymphocytes of cord blood origin were also reactive in lymphoproliferation. Their interferon production was low, but this has been established previously for mitogens in general. During the course of the studies, different batches of MAS were tested, including most recently a purified preparation. All of these were active. Removal of accessory cells adherent to nylon wool column abolished MAS reactivity, whereas it has little effect on lymphoproliferation induced by phytohaemagglutinin (PHA). MAS reactivity was also strongly reduced when monoclonal anti-HLA-DR antibodies were added to the leucocyte cultures.

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1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

Short photoperiod induces growth cessation in seedlings of Norway spruce (Picea abies (L.] Karst.). Application of different gibberellins (GAS) to seedlings growing under a short photoperiod show that GA9 and GA20 can not induce growth. In contrast application of GA, and GA4 induced shoot elongation. The results indicate that 3β-hydroxylation of GA9 to GA4 and of GA20 to GA1 is under photoperiodic control. To confirm that conclusion, both qualitative and quantitative analyses of endogenous GAs were performed. GA1, GA3, GA4, GA7, GA9, GA12, GA15, GA15, GA20, GA29, GA34 and GA51 were identified by combined gas chromatography-mass spectrometry in shoots of Norway spruce seedlings. The effect of photoperiod on GA levels was determined by using deuterated and 14C-labelled GAs as intermal standards. In short days, the amounts of GA9, GA4 and GA1 are less than in plants grown in continuous light. There is no significant difference in the amounts of GA3, GA12, and GA20 between the different photoperiods. The lack of accumulation of GA9 and GA20 under short days is discussed.

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1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

In the temperate-zone woody species Salix pentandra elongation growth is regulated by the photoperiod. Long days sustain active growth, whereas short days induce cessation of apical growth, which is a prerequisite for winter hardening. It is shown that this is correlated to quantitative changes in levels of endogenous GA19 GA20, and GA1. Within two short days the amount of the active GA1 and its immediate precursor GA20, decreased markedly in young leaves us well as in stem tissue. Also, the amount of GA19, declined, but the decrease was delayed relative to that of GA1 and GA20. The ability of S. pentandra seedlings to respond to exogenous GA19, decreased with increasing numbers of short days. Observations that support the hypothesis that the level of GA1 in S. pentandra is regulated by the photoperiod in a quantitative mode with conversion of GA19, to GA20, being one target for control.Different distribution of GAs in various plant parts was observed. The level of GA was higher in young leaves than in other plant parts, and the amount of GA19 was 5–10 times higher in stem tissue than in leaves and roots. The ratios of GA8 to GA1 and GA20, were higher in roots as compared with other parts, as rods contained very low levels of GA1 and GA20, but amounts of GA20 comparable with other parts.

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1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

The application of gibberellin A4/7 (GA4/7) to the stem of previous-year (1-year-old) terminal shoots of Scots pine (Pinus sylvestris) seedlings has been observed to stimulate cambial growth locally, as well as at a distance in the distal current-year terminal shoot, but the distribution and metabolic fate of the applied GA4/7, as well as the pathway of endogenous GA biosynthesis in this species, has not been investigated. As a first step, we analysed for endogenous GAs and monitored the transport and metabolism of labelled GAs 4, 9 and 20. Endogenous GAs from the elongating current-year terminal shoot of 2-year-old seedlings were purified by column chromatography and high-performance liquid chromatography and analysed by combined gas chromatography-mass spectrometry (GC-MS). GAs 1, 3, 4, 9, 12 and 20 were identified in the stem, and GAs 1, 3 and 4 in the needles, by full-scan mass spectrometry (GAs 1, 3, 4, 9 and 12) or selected-ion monitoring (GA20) and Kovats retention index. Tritiated and deuterated GA4, GA9 or GA20 were applied around the circumference at the midpoint of the previous-year terminal shoot, and metabolites were extracted from the elongating current-year terminal shoot, the application point, and the 1-year-old needles and the cambial region above and below the application point. After purification, detection by liquid scintillation spectrometry and analysis by GC-MS, it was evident that, for each applied GA, unmetabolised [2H2]GA and [3H]radioactivity were present in every seedling part analysed. Most of the radioactivity was retained at the application point when [3H]GA9 and [3H]GA20 were applied, whereas the largest percentage of radioactivity derived from [3H]GA4 was recovered in the current-year terminal shoot. It was also found that [2H2]GA9 was converted to [2H2]GA20 and to both [2H2]GA4 and [2H2]GA1, [2H2]GA4 was metabolised to [2H2]GA1, and [2H2]GA20 was converted to [2H2]GA29. The data indicate that for Pinus sylvestris shoots (1) GAs applied laterally to the outside of the vascular system of previous-year shoots not only are absorbed and translocated extensively throughout the previous-year and current-year shoots, but also are readily metabolised, (2) the GA metabolic pathways found are closely related to the endogenous GAs identified, and (3) GA9 metabolism follows two distinctly different routes: in one, GA9 is converted to GA1 through GA4, and in the other it is converted to GA20, which is then metabolised to GA29. The results suggest that the late 13-hydroxylation pathway is an important route for GA biosynthesis in shoots of Pinus sylvestris, and that the stimulation of cambial growth in Scots pine by exogenous GA4/7 may be due to its conversion to GA1, rather than to it being active per se.

Electronic Resource

1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

The effect of photoperiod on metabolism of 16,17-[3H2]GA19, and 1.2-[3H2]GA1 applied to intact seedlings of Salix pentandra, was investigated. No difference was found in conversion of 16,17-[3H2]GA19 to 16,17-[3H2]GA20, and 16,17-[3H2]GA1, or in metabolism of 1,2-[3H2]GA1 to [3H]GA8 between plants grown in continuous light and plants exposed for 14 days to a 12-h photoperiod. Also, leaf discs from plants grown in long or short days, converted 16,17-[3H2]GA19 both in light and darkness. These data on metabolism of 16,17-[3H2]GA19, contrast with previous results, which have indicated a photoperiodic control of the metabolism of GA19 to GA20 in S. pentandra.Presence of these applied labelled GAs and their metabolites in different parts of seedlings was recorded, after application to intact seedlings as well as to isolated plant parts. When 16,17-[3H2]GA19 was applied through the roots of intact plants, the relative amounts of 16,17-[3H2]GA1 present in leaves and shoot apices were higher than in roots and stems. In corresponding experiments with 1,2-[3H2]GA1, relatively higher amounts of [3H2]GA8 were found in roots and stems than in leaves and shoot apices. Twenty-four hours after application of 16,17-[3H2]GA19 to isolated plant parts, 16,17-[3H2]GA20 and 16,17-[3H2]GA1 were found in leaves and roots, but not in internodes. Incubation of isolated plant parts with 1,2-[3H2]GA1 for 24 h resulted in presence of [3H]GA8 in all parts.The results mentioned above were obtained by monitoring metabolites by HPLC with on-line radio counting. The conversions of 17-[2H2]GA19 to 17-[2H2]GA20 and 17-[2H2]GA1 in shoot apices and whole seedlings, and of 17-[2H2]GA8 in whole seedlings, were confirmed by GC-MS.

Electronic Resource

1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

Gibberellins GA1, GA8. GA19. GA29. GA20 and GA56 (2-epi-GA8). were identified by combined gas chromatography-mass spectrometry in root extracts of elongating Salix pentandra L. seedlings. The presence of GA8 was also demonstrated for the first time in S. pentandra shoots. The levels of GA1, GA8, GA19, GA20 in shoot tissue and in roots were estimated by selected ion monitoring. While the amounts of GA8 and GA19 were similar in both plant parts. the levels of the biologically active GA1 and its immediate precursor GA20. were found to be much lower in roots than in shoots.

Electronic Resource

1432-0851

Springer Online Journal Archives 1860-2000

Medicine

Summary A phase I study with recombinant human tumor necrosis factor α (rhuTNF-α; Knoll AG, Ludwigshafen, FRG) in patients with advanced malignant disease was undertaken to evaluate drug toxicity (organ specifity, time course, predictability, reversibility, maximal tolerated dose), effectiveness, antigenicity and pharmacokinetics. TNF was administered as a test dose followed by daily i.v. infusions for 5 days, every 3 weeks (single i.v. infusion lasting 10 min, TNF dissolved in 50 ml 5% human albumin). Dosage was increased in groups of 3 or 4 patients from 0.04 mg/m2 to 0.28 mg/m2. A total of 19 patients with different cancers, including seven large-bowel carcinomas, three chronic myelogenous leukemias, three hypernephromas, two small-cell lung cancers, one malignant melanoma, one malignant lymphoma, one rhabdomyosarcoma and one fibrosarcoma were treated. Major side-effects were chills and fever (maximum 40.4°C, median 38.7°C, 19/19), headache (12/19), nausea and vomiting (12/19) and pronounced (〉20%) hypotension (4/19). Acute side-effects could be diminished by paracetamol or indomethacin pretreatment, and with one possible exception no tachyphylaxis to TNF was noted. Mild renal toxicity was seen during TNF treatment. Pharmacokinetic studies showed a serum half-life (t 1/2) ranging from 11 min to 17 min for doses from 0.04 mg/m2 to 0.16 mg/m2 and prolonged clearance with t 1/2 ranging from 54 min to 70 min in the 0.20–0.28 mg/m2 dose range. No objective antitumor effects were observed in this phase I study.

Electronic Resource

1432-0584

Springer Online Journal Archives 1860-2000

Medicine

Conclusion The influence of IFN on cellular differentiation is well established in a variety of in vitro models such as Friend erythroleukemia, HL-60 cells or monocyte-macrophage differentiation. The exact effect of interferon, however, differs in special experimental situations. Enhancement of inhibition of terminal differentiation is possible, special subtypes of IFN may act only in a certain model and the effect is sometimes markedly dose dependent. The biochemical basis for the differentiation inducing activity of IFN is unknown, but studies reviewed here suggest that mechanisms different from those inducing the antiviral state are operative. Modulation of oncogene expression may be involved in some differentiation models. Various chemical substances (e. g. TPA, DMSO, retinoic acid) act synergistically with IFN in vitro. Furthermore, it appears that in vivo cellular differentiation processes are regulated by a combined action of IFN and other endogenously produced protein substances. IFN has already been shown to be effective in a small number of malignancies such as hairy cell leukemia, CML, renal carcinoma or non-Hodgkin lymphoma while it shows no or very limited effect in most solid tumors. The exact mechanism of IFN action and the proper dosage for clinical use, however, are still far from being settled. If these problems can be solved, IFN treatment, possibly as part of a multiple agent therapy, may turn out to be useful in future cancer therapy.

Electronic Resource

1432-0584

TNF α ; IFN α-2b ; Leukocytes ; Cortisol ; ACTH ; CML

Springer Online Journal Archives 1860-2000

Medicine

Summary During long-term interferon α-2b (IFN) therapy of Philadelphia chromosome-positive chronic myelogenous leukemia (CML) patients, short-term effects of tumor necrosis factor α (TNF) on peripheral leukocyte counts, as well as cortisol and corticotropin (ACTH) release were studied. TNF (40–160μg/m2) was given as a 2-h infusion on 5 consecutive days every 3 weeks, in addition to s.c. daily IFN injections (4 mio U/m2), to four (two male/two female) patients, who had been treated for more than 8 months with IFN and additionally for 0–7 months with TNF. Leukocyte counts, cortisol, and ACTH were determined at 30-min intervals between 4 p.m. and midnight. Profiles were determined the day before and on day 1 of TNF therapy. Leukocyte numbers decreased 30 min after start of TNF administration and increased 30–60 min later with a rebound until the next TNF application. The increase of leukocyte counts was due mostly to neutrophil granulocytes. ACTH levels increased 30 min, cortisol 60 min, and leukocyte counts 90 min after start of TNF infusion. Metopirone, an inhibitor of cortisol synthesis given to one patient, suppressed the TNF-induced stimulation of cortisol secretion and subsequent increase of leukocyte counts, while ACTH blood levels were enhanced. It was concluded that leukocyte count increases after TNF/IFN administration might be related to TNF-evoked cortisol secretion.

Electronic Resource

1432-1335

Key words Retroviral vector ; Green fluorescent protein ; Gene therapy ; Internal promoter

Springer Online Journal Archives 1860-2000

Medicine

Abstract Purpose: Although gene transfer with retroviral vectors has already been applied to patients as part of clinical protocols, low expression of transgenes in target cells still remains a problem. Therefore, we compared various retroviral vectors using different promoters and backbones for expression of the enhanced green fluorescent protein (EGFP) reporter gene in fibroblasts and CD34+ cells. Methods: The N2A retroviral vector was used to test expression from the herpes simplex virus thymidine kinase promoter (vector N2A-TK-EGFP), a human phosphoglycerate kinase promoter (vector N2A-PGK-EGFP), and the SV40 promoter (vector N2A-SV-EGFP). Additional constructs used the spleen focus-forming virus (SFFV) long terminal repeat (LTR) as promoter and expressed EGFP alone (vector SFβ1-EGFP) or EGFP and a downstream (vector SFβ1-EGFP-IRES) or upstream (vector SFβ1-IRES-EGFP) internal ribosomal entry site. Results: For NIH 3T3 cells the fluorescence-activated cell sorting analysis revealed that the most active internal promoter was the SV40 promoter in the vector N2A-SV-EGFP (mean fluorescence intensity, MFI, 66.7 ± 0.4), followed by N2A-PGK-EGFP (26.3 ± 1.8 MFI), and N2A-TK-EGFP (4.8 ± 0.1 MFI). Expression from the SFβ1-EGFP vector (82.6 ± 6.7 MFI) and the SFβ1-EGFP-IRES vector (102.8 ± 6.2 MFI) was higher than from SFβ1-IRES-EGFP vector (15.5 ± 1.8 MFI). In human CD34-positive cells, the EGFP expression from all vectors was considerably lower than in fibroblasts with the SFβ1-EGFP vector still being four- to fivefold more active than the internal promoters tested. Conclusion: The SFFV LTR seems to allow a high expression of transgenes, as long as the transgene is not expressed downstream of an internal ribosomal entry site. Internal promoters may be useful for targeted gene expression in specific cell types, but the reduced level of expression from some internal promoters has to be taken into consideration.

Electronic Resource

1432-2048

Caffeine ; Catabolism pathways ; Coffea ; Purine alkaloids

Springer Online Journal Archives 1860-2000

Biology

Abstract In a study of purine alkaloid catabolism pathways in coffee,14C-labelled theobromine, caffeine, theophylline and xanthine were incubated with leaves ofCoffea arabica. Incorporation of label into14CO2 was determined and methanol-soluble metabolites were analysed by high-performance liquid chromatography-radiocounting. The data obtained demonstrate catabolism of caffeine → theophylline → 3-methylxanthine → xanthine. Xanthine is degraded further by the conventional purine catabolism pathway to CO2 and NH3 via uric acid, allantoin and allantoic acid. The conversion of caffeine to theophylline is the rate-limiting step in purine alkaloid catabolism and provides a ready explanation for the high concentration of endogenous caffeine found inC. arabica leaves. Although theobromine is converted primarily to caffeine, a small portion of the theobromine pool appears to be degraded to xanthine by a caffeine-independent pathway. In addition to being broken down to CO2, via the purine catabolism pathway, xanthine is metabolised to 7-methylxanthine. Metabolism of [2-14C]xanthine byC. arabica leaves in the presence of 5 mM allopurinol results in very large increases in incorporation of radioactivity into 7-methylxanthine as degradation of the substrate via the purine catabolism pathway is blocked. The identity of 7-methylxanthine in these studies was confirmed by gas chromatography-mass spectrometry analysis.

Electronic Resource

1573-4854

functionally graded materials ; pore size gradient ; centrifugal deposition ; microwave drying ; critical point drying

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Abstract Thin self-supporting ceramic TiO2-layers with a graded pore structure were prepared by using centrifugal deposition of powders and sols with different particle size distributions from mixed, diluted suspensions. During the evaporation drying step the layers have a strong tendency to warping and crack-formation because of the resulting difference in the capillary pressure in the upper and the bottom side pores. Four drying methods were investigated concerning their suitability for diminishing or eliminating capillary forces and for the production of planar, crack-free dried specimens. The drying techniques used in the experiments are briefly introduced. It should be emphasized that the most successful drying method for the layers mentioned above is a combination of microwave drying and subsequent critical point drying.

Electronic Resource

1435-8107

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract Prohexadione, a gibberellin (GA) biosynthesis inhibitor, was applied in ethanol around the circumference at the midpoint of the previous year terminal shoot of dormant Pinus sylvestris seedlings. After cultivating the seedlings under environmental conditions favorable for growth for 10 weeks, longitudinal and cambial growth were measured, and the endogenous levels of GA1, GA3, GA4, GA9, and indole-3-acetic acid (IAA) were determined by combined gas chromatography-mass spectrometry, using deuterated GAs and [13C6]IAA as internal standards. Prohexadione application inhibited elongation and xylem and phloem production in the current year terminal shoot and xylem production in the previous year terminal shoots. Concomitantly, in both ages of shoots the cambial region contents of GA1; GA3, and GA4 were decreased, whereas the level of GA9 was increased. However, the IAA content was not altered in the terminal bud on the current year terminal shoot or in the cambial region of the current year or previous year terminal shoots. The results provide additional evidence that: (1) GAs are involved in the regulation of cambial growth, as well as longitudinal growth, in Pinus sylvestris shoots; (2) they act directly, rather than indirectly, by altering the IAA level; and (3) the GA9 → GA4 → GA1 pathway is a major route of GA biosynthesis in conifer species.

Electronic Resource

1573-4803

Springer Online Journal Archives 1860-2000

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Abstract The topic of this work is the investigation of the sintering process of thin self-supporting ceramic layers with a gradient in the particle size and pore size distribution. These graded titania layers were produced by zentrifugal deposition from mixed sol powder mixtures with wide particle size distributions. The graded structure causes strong deformations of the layers during the drying and the sintering step. Finite element simulations were used to describe the deformation behaviour during sintering. The results were compared with the parpage of real layers. Furthermore, a possibility to suppress a sintering deformation is shown with the help of experimental and simulated data. The sintered layers were charakterized by SEM, AFM, gas adsorption and roughness measurements. Quantitative image analysis of polished cross-sections and AFM investigations of ion beam cutted slopes were used for detecting the run of the pore size gradient within the layers.

Electronic Resource

2018-04-03

American Physical Society (APS)

1098-0121

1095-3795

Physics

Superfluidity and superconductivity