Ökonomische Aspekte einer EU-Richtlinie zur Versicherungsvermittlung

„Was lange währt wird endlich gut“ ist eine Hoffnung, die freilich häufig trügt. Die bekannte Empfehlung der EG-Kommission über Versicherungsvermittler führte weder in der gesetzten Dreijahresfrist für einen Bericht an die Kommission noch danach zu einer entsprechenden rechtlichen Regelung in Deutschland. Auch die Deregulierung des deutschen Versicherungsmarktes im Jahre 1994, die in der bis heute nicht verstummten Fachdiskussion verbreitet als ein gewichtiges Argument für eine Regulierung der Versicherungsvermittlung vorgetragen wurde, hat nicht zu einer Änderung Anlass gegeben. Zur Zeit wird in Brüssel an einem Vorschlag für eine „Richtlinie des Europäischen Parlaments und des Rates über Versicherungsvermittlung“ gearbeitet, der am 26. November 2001 zu einem politischen Agreement geführt hat. Dieser Vorschlag ist Anlass für die folgenden Ausführungen, die jedoch nicht auf eine detaillierte Kritik einzelner Formulierungen von geplanten Vorschriften gerichtet ist. Dazu erscheint es in diesem Stadium der Vorbereitungen und in Anbetracht einer ganzen Reihe von Optionen der Mitgliedstaaten für die Konkretisierung der Regelungen bei der Transformation in nationales Recht, noch zu früh. Vielmehr sollen wirtschaftliche Beobachtungen und allgemeinere theoretische Überlegungen, die für eine eher grundsätzliche Beurteilung von Bedeutung sind, erörtert werden. --

Some histochemical observations on the telencephalon of the bullfrog, Rana catesbeiana shaw

The histochemically determined distribution of acetylcholinesterase, monoamine oxidase and succinate dehydrogenase in the telencephalon of the bullfrog supports the classically recognized divisions of the pallium and subpallium. Analysis also corroborates the following gernerally recognized anuran-amniotic homologies: anuran medial pallium to amniotic medial cortex anuran septal nuclei to amniotic septal nuclei, anuran striatum to amniotic corpus striatum. On topographical and histochemical criteria the ventrocaudal and basomedial portions of the anuran telencephalon are considered possible homologues to the mammalian amygdala. It is suggested that two divisions can be recognized: a pars lateralis which may be homologous to the mammalian cortico-medial group. And a pars medialis which may be homologous to the mammalian baso-lateral group. Further analysis suggests, particularly when viewed in the light of recent experimental anatomical studies, that the anuran lateral pallium consists of a pars dorsalis and a pars ventralis. The pars dorsalis may be the reptilian homologue of the dorsal cortex and the pars ventralis may be the field homologue of both the reptilian piriform cortex and the dorsal ventricular ridge.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49994/1/901570403_ftp.pd

Vakoverstijgend onderwijs op het Gymnasium

Teaching and Teacher Learning (ICLON

Vakoverstijgend onderwijs op het gymnasium

Teaching and Teacher Learning (ICLON

Nerve growth factor is expressed by postmitotic avian retinal horizontal cells and supports their survival during development in an autocrine mode of action.

Cell death in the developing retina is regulated, but so far little is known about what factors regulate the cell death. Several neurotrophic factors and receptors, including the neurotrophins and Trk receptors, are expressed during the critical time. We have studied the developing avian retina with respect to the role of nerve growth factor (NGF) in these processes. Our starting point for the work was that NGF and its receptor TrkA are expressed in a partially overlapping pattern in the inner nuclear layer of the developing retina. Our results show that TrkA and NGF-expressing cells are postmitotic. The first NGF-expressing cells were found on the vitreal side of the central region of E5.5–E6 retina. This pattern changed and NGF-expressing cells identified as horizontal cells were later confined to the external inner nuclear layer. We show that these horizontal cells co-express TrkA and NGF, unlike a subpopulation of amacrine cells that only expresses TrkA. In contrast to the horizontal cells, which survive, the majority of the TrkA-expressing amacrine cells die during a period of cell death in the inner nuclear layer. Intraocular injections of NGF protein rescued the dying amacrine cells and injection of antisense oligonucleotides for NGF that block its synthesis, caused death among the TrkA-expressing horizontal cells, which normally would survive. Our results suggest that NGF supports the survival of TrkA expressing avian horizontal cells in an autocrine mode of action in the retina of E10-E12 chicks. The cells co-express TrkA and NGF and the role for NGF is to maintain the TrkA-expressing horizontal cells. The TrkA-expressing amacrine cells are not supported by NGF and subsequently die. In addition to the effect on survival, our results suggest that NGF plays a role in horizontal cell plasticity

Afferents to the optic tectum of the leopard frog: An HRP study

Folowing unilateral HRP injections in the optic tectum of Ran pipiens , HRP - positive cells were seen in three pretectal nuclei: bilaterally in the dorsal posterior nucleus; in the dorsal half of the ipsilateral posterior nucleus; and ipsilaterally in the large-celled pretectal nucleus. HRP -positive cells were also seen ipsilaterally in the anterodorsal, posterodorsal and posteroventral tegmental fields, the nucleus isthmi, and the dorsal gray columns of the cervical spinal cord; bilaterally in the suprapeduncular nucleus, a paramedian cell group dorsal to the interpeduncular nucleus; and in the deep layers of the contralateral tectum. In addition, evidence for a bilateral ventral preopto-tectal projection was seen in half the experimental animals. No tectal afferents from telencephalic or rostral thalamic areas were seen. Both the ascending and descending tectal efferent fibers were also filled with reaction product. The pale reaction indicative of terminating tectal efferents was seen in the dorsal pretectum, partially overlapping the lateral nucleus and uncinate neuropil; in the core of nucleus isthmi; and in the superior olive.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49999/1/901730202_ftp.pd

Evolution of the amniote basal ganglia

Recent findings indicate that the basal ganglia of amniotes, i.e. modern birds, reptiles and mammals, contain similar neuronal subpopulations, as defined by the transmitters these neurons use and their connections. These data suggest that the evolution of the basal ganglia has been much more conservative than once believed and that this region of the forebrain performs a similar motor role in birds, reptiles and mammals. The basal ganglia of birds and reptiles, however, differ from those of mammals in that they appear to have their major influence over motor functions by an output to the tectum via the pretectum. In contrast, the mammalian basal ganglia are thought to have their major influence over motor functions by an output to the motor cortex via the thalamus.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24712/1/0000133.pd

The distribution of enkephalinlike immunoreactivity in the telencephalon of the adult and developing domestic chicken

Immunohistochemical techniques were used to determine the distribution of enkephalinlike immunoreactivity in the telencephalon of chicken. The densest accumulation of enkephalinergic neurons and fibers was observed within the paleostriatal complex, the avian equivalent of the mammalian basal ganglia. Numerous small enkephalinergic neurons were observed in both lobus parolfactorius (LPO) and the paleostriatum augmentatum (PA), the two components of the small-celled portion of the paleostriatal complex. The enkephalinergic neurons of LPO-PA appeared to give rise to a dense plexus of enkephalinergic fibers within the large-celled zone of the paleostriatal complex, the paleostriatum primitivum (PP). The distribution of enkephalin within the avian paleostriatial complex, when compared to the distribution of enkephalin within the mammalian basal ganglia, supports previous proposals that PP is comparable to the mammalian globus pallidus and that PA-LPO are comparable to the caudate-putamen (Karten and Dubbeldam, '73; Kitt and Brauth, '81; Parent and Olivier, '70; Reiner et al., '83). Observations on the development of enkephalinlike immunoreactivity within the chicken paleostriatal complex also support the suggestion that the major component nuclei of the avian paleostriatal complex have correspondents within the mammalian basal ganglia. Enkephalinlike immunoreactivity was also observed within cell bodies and fibers in other portions of the avian telencephalon. Within the ventrolateral telencephalon, the nucleus accumbens, nucleus of the diagonal band, and tuberculum olfactorium contained enkephalinergic cell bodies and fibers while only enkephalinergic fibers were observed in the portion of the avian telencephalon that has been termed the ventral paleostriatum (Kitt and Brauth, '81; Reiner et al., '83). Within the medial wall of the telencephalon, enkephalinergic fibers were observed in the lateral septal nucleus, while enkephalinergic cell bodies and fibers were observed in the parahippocampal area. Little enkephalinlike immunoreactivity was observed dorsal to the paleostriatal complex except in the hyperstriatum dorsale. Within the hyperstriatum dorsale, a band of enkephalinergic neurons appeared to give rise to an overlying parallel band of dense enkephalinergic fibers. The distribution of enkephalinlike immunoreactivity within the avian telencephalon thus shows remarkable similarity to that seen in the mammalian telencephalon. The largest accumulation of enkephalinlike immunoreactivity within the telencephalon of both vertebrate classes appears to be found within the ventrolateral wall of the telencephalon, including the basal ganglia. In comparison, much less enkephalinlike immunoreactivity is observed in either the mammalian neocortex or in the avian correspondent of mammalian neocortex.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50024/1/902280210_ftp.pd

Palmitoleic acid prevents palmitic acid-induced macrophage activation and consequent p38 MAPK-mediated-skeletal muscle insulin resistance

Obesity and saturated fatty acid (SFA) treatment are both associated with skeletal muscle insulin resistance (IR) and increased macrophage infiltration. However, the relative effects of SFA and unsaturated fatty acid (UFA)-activated macrophages on muscle are unknown. Here, macrophages were treated with palmitic acid, palmitoleic acid or both and the effects of the conditioned medium (CM) on C2C12 myotubes investigated. CM from palmitic acid-treated J774s (palm-mac-CM) impaired insulin signalling and insulin-stimulated glycogen synthesis, reduced Inhibitor κBα and increased phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase in myotubes. p38 MAPK inhibition or siRNA partially ameliorated these defects, as did addition of tumour necrosis factor-α blocking antibody to the CM. Macrophages incubated with both FAs generated CM that did not induce IR, while palmitoleic acid-mac-CM alone was insulin sensitising. Thus UFAs may improve muscle insulin sensitivity and counteract SFA-mediated IR through an effect on macrophage activation