5,044 research outputs found
Ein neuer AufschluĂ im Ăberschiebungsgebiet des sĂŒdlichen HĂŒggel-Vorlandes
Im Steinbruch der Fa. SCHĂNHOFF, am Westrand des Silberberges (TK 25, BI. 3713 Hasbergen, R 342800/H 578695), wird Dolomitstein der Zechstein-Zeit, wahrscheinlich des Leine-Zyklus (HARMS 1981) abgebaut. In den letzten Jahren wurde der Abbau nach Nordwesten verlagert
Coping with Childbirth: Brain Structural Associations of Personal Growth Initiative
Major life events require psychological adaptations and can be accompanied by
brain structural and functional changes. The goal of the current study was to
investigate the association of personal growth initiative (PGI) as a form of
proactive coping strategy before childbirth, with gray matter volume after
delivery. Childbirth is one of the few predictable major life events, which,
while being one of the most positive experiences for many, is also accompanied
by multidimensional stress for the mother. Previous research has shown that
high stress is associated with reductions in gray matter volume in limbic
cortices as well as the prefrontal cortex (PFC). We hypothesized that PGI
before childbirth is positively related to gray matter volume after delivery,
especially in the ventromedial PFC (vmPFC). In a prospective study, 22 first-
time mothers answered questionnaires about their PGI level 1 month before
birth (T1) and 1 month after delivery (T2). Four months after giving birth, a
follow-up assessment was applied with 16 of these mothers (T3). Structural
brain data were acquired at both postpartal measurement occasions. Voxel-based
morphometry was used to correlate prenatal PGI levels with postpartal gray
matter volume. Higher PGI levels before delivery were positively associated
with larger gray matter volume in the vmPFC directly after childbirth.
Previous structural neuroimaging research in the context of major life events
focused primarily on pathological reactions to stress (e.g., post-traumatic
stress disorder; PTSD). The current study gives initial indications that
proactive coping may be positively associated with gray matter volume in the
vmPFC, a brain region which shows volumetric reductions in PTSD patients
Comparative study of physiological skin parameters affecting percutaneous penetration in different mammalian species
1\. Deckblatt
2\. Druckgenehmigung
3\. Widmung
4\. Inhaltsverzeichnis
5\. AbkĂŒrzungen
6\. Einleitung
7\. LiteraturĂŒbersicht
8\. Fragestellung und Zielsetzung
9\. Eigene Untersuchungen
10\. Diskussion
11\. Zusammenfassung
12\. Summary
13\. Literaturverzeichnis
14\. Danksagung
16\. Eidesstattliche ErklÀrungDie perkutane Penetration topisch applizierter Substanzen ist ein Prozess, der
maĂgeblich von den hautphysiologischen Gegebenheiten eines Organismus abhĂ€ngt.
Dabei ist das AusmaĂ der Penetration innerhalb der verschiedenen Tierarten
sehr variabel. In der vorliegenden Arbeit wurden die Morphologie und
Verteilung der Haarfollikel, sowie die Zusammensetzung der interzellulÀren
Lipidmatrix, vergleichend innerhalb verschiedener Haustier- und
Versuchstierspezies analysiert. Im ersten Teil wurde die
Haarfollikelmorphologie, sowie die Dichte der Follikel, mit Hilfe der
Follikelbiopsie durch Cyanacrylat (CSSB) analysiert. Es wurde gezeigt, dass
GröĂe und Verteilung der Follikel speziesabhĂ€ngig variieren. Hund und
Meerschweinchen besitzen die gröĂte SpeicherkapazitĂ€t in den Haarfollikeln.
Mit der Kalkulation des follikulÀren Volumens existieren nun Daten, die die
ReservoirkapazitÀt der Follikel von Tieren nÀher charakterisieren. Mit der
follikulĂ€ren OberflĂ€che, die auch als VergröĂerung der ResorptionsflĂ€che zu
verstehen ist, wurde ein Parameter gefunden, dem im Hinblick auf die kutane
PermeabilitĂ€t die gröĂte Bedeutung beigemessen werden muss. Es wurde gezeigt,
dass ein direkter Zusammenhang zwischen der PermeabilitÀt der Haut von Tieren
und der FollikeloberflÀche besteht. Damit muss den Follikeln beim Kaninchen
und beim Hund die gröĂte Bedeutung beigemessen werden, wĂ€hrend fĂŒr den Affen
und das Schwein wurden die geringsten Werte ermittelt wurden. Die Vermessung
der Haarfollikel durch die CSSB Technik bringt erstmalig, ĂŒber den bisherigen
Stand der Literatur hinausgehende, objektive Parameter hervor, die die
Morphologie der Follikel bei Tieren exakter beschreiben. Im zweiten Teil der
Arbeit wurde die Zusammensetzung der interzellulÀren Stratum corneum Lipide
bei verschiedenen Tierarten untersucht. Die Anteile der Hauptkomponenten
Cholesterol, Ceramide, freie FettsÀuren und Cholesterolester wurden in der
isolierten Stratum corneum Lipidmatrix verschiedener Spezies analysiert. Der
Vergleich der Zusammensetzung, sowie der VerhÀltnisse der vier Lipidklassen
zueinander mit der HautpermeabilitÀt der einzelnen Tiere zeigt deren Bedeutung
fĂŒr das speziesabhĂ€ngige unterschiedliche Penetrationsverhalten. FĂŒr jede der
vier untersuchten Spezies wurde in dieser Arbeit ein charakteristisches
Ceramidmuster nachgewiesen. Einen weiteren neuen Ansatz fĂŒr das VerstĂ€ndnis
der Rolle der Lipidzusammensetzung in der perkutanen Penetration bietet
möglicherweise das Cholesterol Ceramid VerhĂ€ltnis, das erstmals fĂŒr eine
Tierart evaluiert wurde. Damit bietet die vorliegende Arbeit neue grundlegende
AnsĂ€tze fĂŒr das VerstĂ€ndnis der perkutanen Penetration bei Tieren. Die
BerĂŒcksichtigung der erfassten morphologischen Unterschiede trĂ€gt entscheidend
zur Optimierung individuell an die einzelne Tierart angepasster topischer
Medikamente bei. SchlieĂlich werden mit den vorliegenden Daten weitere
Argumente geliefert, dass der Einsatz der Labornager, sowie des Kaninchens als
Ersatzmodelle fĂŒr die Haut des Menschen in Ermangelung vergleichbarer
hautphysiologischer Kriterien nicht empfohlen werden kann. DemgegenĂŒber stehen
Schwein und Affe, deren Haut sowohl aus morphologischer Sicht der
Haarfollikel, als auch hinsichtlich der Lipidkomposition des SC der Haut des
Menschen am Àhnlichsten und kann demnach gut als Ersatzmodell eingesetzt
werden.Skin physiology significantly influences percutaneous penetration and varies
among mammalian species. The two major routes that substances pass through the
skin are the follicular and the intercellular pathways. Both routes were
investigated in animals. Hair follicle morphology and distribution were
analysed using cyanoacrylate skin surface biopsies (CSSB). CSSB analysis of
hair follicles revealed objective parameters characterizing hair follicle
morphology in mammalian species for the first time. The follicular volume is a
novel parameter describing reservoir capacity of hair follicles in animal
species. It was proven that follicular surface and skin permeability are
directly linked. For the first time, a comprehensive study involving numerous
species and individuals demonstrated that individual hair follicle morphology
is a key point for the understanding of skin permeability and follicular
penetration. The four major components of the intercellular stratum corneum
lipids: cholesterol, ceramides, free fatty acids and cholesterolester were
analysed. The ratios of the four major lipid classes regarding skin
permeability were examined. Four animal species were investigated: pigs and
for the first time dogs, cats and rabbits. A characteristic species-dependent
pattern of ceramides, representing the composition of the different ceramide
classes, was proven to exist in stratum corneum lipid matrix. A further
approach for understanding the relevance of the stratum corneum lipid
composition is represented by the cholesterol-ceramide ratio. Thus, a
correlation of lipid composition and skin permeability as demonstrated in
human beings has been established in the four species. This study provides
fundamental knowledge for the understanding of percutaneous penetration of
animal species. The measurement of species-specific follicle parameters allows
the calculation of the follicular reservoir capacity and resorption for
substances applied to the skin and more accurately estimates follicular
penetration. This knowledge is of particular relevance in the processing of
topical drugs. The development of individually adapted drugs in veterinary
medicine can be optimized if morphological differences among the species are
adequately considered. Finally, the data in this work contributes to the
evidence-based recommendation that laboratory animals such as mice, rats,
guinea pigs and rabbits are not appropriate models for human skin research.
The porcine pinna appears to be the most appropriate pragmatic experimental
paradigm for the exploration of human skin pharmacolog
The Relationship Between Law and Sin in Romans 7
It is the purpose of this thesis to develop an answer to the question, \u27\u27What is the relationship between law and sin in Romans 7? It is important to note that this inquiry is based on two presuppositions. The first is that there really is a relationship between law and sin in Romans 7. The second is that Romans 7 can validly be studied in the light of that relationship. The second assumption is based on the first and is more significant, because it determines the method to be used in answering the problem to which this thesis proposes to address itself. It is this second presupposition which makes it unnecessary to present a detailed exegesis of every aspect of Romans 7 within this dissertation. Our method will consist, therefore, in defining the terms law and sin as they are used by Paul and proceeding from there to show how law and sin interact when they meet in man
Der Einfluss von Exporten auf die betriebliche Entwicklung
Exporte gelten als Wachstumsmotor der deutschen Wirtschaft und werden von der Wirtschaftspolitik auf vielfĂ€ltige Weise gefördert. Doch fĂŒhrt die Förderung der Aufnahme von Handelsbeziehungen mit dem Ausland durch Betriebe, die bislang nicht exportierten, wirklich zu einem Wachstum der ProduktivitĂ€t in der deutschen Wirtschaft? Oder werden besonders produktive Betriebe von sich aus zu Exporteuren und mĂŒssen nicht gefördert werden? Dies ist eine sehr interessante Frage fur die Wirtschaftspolitik und ihr soll in dieser Arbeit nachgegangen werden.export-led growth, trade, productivity, firm heterogeneity
1,25-Dihydroxyvitamin D3-induced differentiation in a human promyelocytic leukemia cell line (HL-60): receptor-mediated maturation to macrophage-like cells.
The human-derived promyelocytic leukemia cell line, HL-60, is known to differentiate into mature myeloid cells in the presence of 1,25-dihydroxyvitamin D3 (1,25[OH]2D3). We investigated differentiation by monitoring 1,25(OH)2D3-exposed HL-60 cells for phagocytic activity, ability to reduce nitroblue tetrazolium, binding of the chemotaxin N-formyl-methionyl-leucyl-[3H]phenylalanine, development of nonspecific acid esterase activity, and morphological maturation of Wright-Giemsa-stained cells. 1,25(OH)2D3 concentrations as low as 10(-10) M caused significant development of phagocytosis, nitroblue tetrazolium reduction, and the emergence of differentiated myeloid cells that had morphological characteristics of both metamyelocytes and monocytes. These cells were conclusively identified as monocytes/macrophages based upon their adherence to the plastic flasks and their content of the macrophage-characteristic nonspecific acid esterase enzyme. The estimated ED50 for 1,25(OH)2D3-induced differentiation based upon nitroblue tetrazolium reduction and N-formyl-methionyl-leucyl-[3H]phenylalanine binding was 5.7 X 10(-9) M. HL-60 cells exhibited a complex growth response with various levels of 1,25(OH)2D3: less than or equal to 10(-10) M had no detectable effect, 10(-9) M stimulated growth, and greater than or equal to 10(-8) M sharply inhibited proliferation. We also detected and quantitated the specific receptor for 1,25(OH)2D3 in HL-60 and HL-60 Blast, a sub-clone resistant to the growth and differentiation effects of 1,25(OH)2D3. The receptor in both lines was characterized as a DNA-binding protein that migrated at 3.3S on high-salt sucrose gradients. Unequivocal identification was provided by selective dissociation of the 1,25(OH)2D3-receptor complex with the mercurial reagent, p-chloromercuribenzenesulfonic acid, and by a shift in its sedimentation position upon complexing with anti-receptor monoclonal antibody. On the basis of labeling of whole cells with 1,25(OH)2[3H]D3 in culture, we found that HL-60 contains approximately 4,000 1,25(OH)2D3 receptor molecules per cell, while the nonresponsive HL-60 Blast is endowed with approximately 8% of that number. The concentration of 1,25(OH)2D3 (5 X 10(-9) M) in complete culture medium, which facilitates the saturation of receptors in HL-60 cells, is virtually identical to the ED50 for the sterol's induction of differentiation. This correspondence, plus the resistance of the relatively receptor-poor HL-60 Blast, indicates that 1,25(OH)2D3-induced differentiation of HL-60 cells to monocytes/macrophages is occurring via receptor-mediated events
Mutagenicity testing with transgenic mice. Part I: Comparison with the mouse bone marrow micronucleus test
As part of a larger literature study on transgenic animals in mutagenicity testing, test results from the transgenic mutagenicity assays (lacI model; commercially available as the Big Blue(Âź )mouse, and the lacZ model; commercially available as the MutaâąMouse), were compared with the results on the same substances in the more traditional mouse bone marrow micronucleus test. 39 substances were found which had been tested in the micronucleus assay and in the above transgenic mouse systems. Although, the transgenic animal mutation assay is not directly comparable with the micronucleus test, because different genetic endpoints are examined: chromosome aberration versus gene mutation, the results for the majority of substances were in agreement. Both test systems, the transgenic mouse assay and the mouse bone marrow micronucleus test, have advantages and they complement each other. However, the transgenic animal assay has some distinct advantages over the micronucleus test: it is not restricted to one target organ and detects systemic as well as local mutagenic effects
What makes a thriver? Unifying the concepts of posttraumatic and postecstatic growth
The thriver model is a novel framework that unifies the concepts of
posttraumatic and postecstatic growth. According to the model, it is not the
quality of an event, but the way it is processed, that is critical for the
occurrence of post-event growth. The model proposes that meaning making,
supportive relationships, and positive emotions facilitate growth processes
after positive as well as traumatic experiences. The tenability of these
propositions was investigated in two dissimilar cultures. In Study 1,
participants from the USA (n = 555) and India (n = 599) answered an extended
version of the Social Readjustment Rating Scale to rank the socioemotional
impact of events. Results indicate that negative events are perceived as more
impactful than positive ones in the USA, whereas the reverse is true in India.
In Study 2, participants from the USA (n = 342) and India (n = 341) answered
questions about the thriver model's main components. Results showed that
posttraumatic and postecstatic growth are highly interrelated. All elements of
the thriver model were key variables for the prediction of growth. Supportive
relationships and positive emotions had a direct effect on growth, while
meaning making mediated the direct effect of major life events
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