Особенности школьной организационной культуры

Рассматривается основное содержание понятия «школьная организационная культура», функции и потенциал использования организационной культуры в общеобразовательных учреждениях. Выявляются особенности школьной организационной культуры. Обосновывается взаимосвязь организационной культуры и социально-психологического климата общеобразовательного учреждени

Representative AFM images of individual, dissociated IC cells.

<p>AFM error signal (1) and height (2) images of four morphologically different cells (A–D) are presented. For possible cell type specification, the reader is referred to Chapter 3.2, AFM results. Arrowhead and asterisk denote the nucleus. Scale bar: 20 µm.</p

Dissociated Neurons and Glial Cells Derived from Rat Inferior Colliculi after Digestion with Papain

<div><p>The formation of gliosis around implant electrodes for deep brain stimulation impairs electrode–tissue interaction. Unspecific growth of glial tissue around the electrodes can be hindered by altering physicochemical material properties. However, in vitro screening of neural tissue–material interaction requires an adequate cell culture system. No adequate model for cells dissociated from the inferior colliculus (IC) has been described and was thus the aim of this study. Therefore, IC were isolated from neonatal rats (P3<b>_</b>5) and a dissociated cell culture was established. In screening experiments using four dissociation methods (Neural Tissue Dissociation Kit [NTDK] T, NTDK P; NTDK PN, and a validated protocol for the dissociation of spiral ganglion neurons [SGN]), the optimal media, and seeding densities were identified. Thereafter, a dissociation protocol containing only the proteolytic enzymes of interest (trypsin or papain) was tested. For analysis, cells were fixed and immunolabeled using glial- and neuron-specific antibodies. Adhesion and survival of dissociated neurons and glial cells isolated from the IC were demonstrated in all experimental settings. Hence, preservation of type-specific cytoarchitecture with sufficient neuronal networks only occurred in cultures dissociated with NTDK P, NTDK PN, and fresh prepared papain solution. However, cultures obtained after dissociation with papain, seeded at a density of 2<b>×</b>10⁴ cells/well and cultivated with Neuro Medium for 6 days reliably revealed the highest neuronal yield with excellent cytoarchitecture of neurons and glial cells. The herein described dissociated culture can be utilized as in vitro model to screen interactions between cells of the IC and surface modifications of the electrode.</p></div

Oxygen treatment scheme.

<p>Oxygen treatment scheme.</p

Synoptic representation of the proteolytic enzymes used for dissociation.

<p><i>Each assay includes at least two independent preparations with 2–10 wells;</i></p><p><i>w/ = with DNase I.</i></p><p><i>w/o = without DNase I.</i></p

Proliferation of HBO-treated cells.

<p>The effect of hyperbaric oxygen (HBO) treatment on the proliferation of NIH3T3 fibroblasts (A), genetically modified NIH3T3/BDNF fibroblasts (B) and MSCs (C) is depicted. HBO was applied at three different pressures: 1.0 bar (red circle and line), 1.5 bar (blue square and line) and 2.0 bar (orange triangle and line). Both NIH3T3 and NIH3T3/BDNF fibroblasts show a highly significantly increased cell number compared to the control cells (normoxic and normobaric conditions (NOR), green inverted triangle and line) after five consecutive HBO treatments. By contrast, the proliferation of MSCs started to decrease after five consecutive HBO treatments with 2.0 bar until the end of ten treatments in comparison to NOR. Values are given as mean ± standard error of the mean (SEM); N = 3, n = 3. Asterisks indicate the significance of cell numbers of the different used pressures compared to the normoxic control. Statistical assessment was performed using one-way ANOVA with Bonferroni’s multiple comparison test (n.s. = not significant; *p < 0.05; **p < 0.01; ***p < 0.001).</p

Fluorescence images of different antibodies for glial cell characterization.

<p>Papain digested cells were labelled with GFAP (red) and MAG (green) and are depicted in the first row. Positive staining for GFAP as well as MAG discriminate astrocytes as well as oligodendrocytes, respectively. A second astrocytic marker (S100, red) was also tested in combination with TUJ1 (green) and presented in the second row. Positive staining for S100 confirmed previously obtained results with GFAP (second row). Two different magnifications are presented in the left (20×; scale bar: 100 µm) and right column (40×; scale bar: 50 µm).</p

Results^$ obtained from the screening experiments for seeding densities.

<p><i>CP: cultivation period;</i></p><p><i>SD: seeding density.</i></p>$<p><i>For a better overview, only results from one preparation were shown for 5 days of cultivation.</i></p>§<p><i>spheroidal morphology with no or short neurites (restricted neuronal morphology);</i></p><p><i><u>Confluency:</u> rated confluency in per cent; optical evaluation of the whole well under bright-field conditions using a 40-fold magnification;</i></p><p><i><u>Cell debris, conglomerates, and neuronal yield</u>.</i></p><p><i>−: no debris, conglomerates, or neurons;</i></p><p><i>+: poor amount; +(+): poor-middle;</i></p><p><i>++: middle amount; ++(+): middle-high;</i></p><p><i>+++: high amount.</i></p

Fluorescent images from the testing of proteolytic enzymes.

<p>Cells digested either with trypsin (15 min: first row) or papain (30 min: second row and 90 min: third row) were triturated without (left column) and with DNase I (right column). Merged pictures of cells labelled with TUJ1 antibody (green) and GFAP antibody (red) were depicted. When comparing all depicted conditions, an improved cytoarchitecture with high neuronal (and glial) yield was obtained in cultures dissociated with papain for 30 min without DNase I. Scale bar: 100 µm.</p

Immunocytochemical results of different dissociation protocols and media.

<p>Improved neuronal yield and branching was observed in cells cultivated for 5 days with MACS® Neuro Medium (right column). By contrast, cells cultivated with Panserin 401 (left column) showed less branching with prominent neurite fragmentation (A, E). IC tissue was dissociated with different protocols: NTDK T (A, B), NTDK P (C, D) and NTDK PN (E, F) as well as SGN-protocol (G, H). After fixation and labelling with TUJ1 (green), poor neuronal yield was obtained after dissociation with NTDK T independent from the cultivation medium. Scale bar: 100 µm.</p