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15 jugendliche Inhaftierte einer Entlassungsabteilung nahmen an einem Modellunterstützten Rollentraining in schwierigen Situationen nach der Entlassung teil. Videoaufnahmen von nicht geübten Szenen wurden im Paarvergleich von Ratern auf die Besserung des Rollenspielverhaltens beurteilt. Die Ergebnisse sprechen für eine Verhaltensbesserung, die auf das Modellunterstützte Rollentraining zurückgeführt werden kann.
Durch BeDbachtungen und Beurteilungen wurde die Durchführbarkeit und Wirksamkeit einer MethDde zur Beeinflussung der Behandlungsbereitschaft bei 30 jugendlichen Strafgefangenen unter zwei VDllzugsbedingungen geprüft. Die MethDde erwies sich bei dieser Stichprobe als durchführbar und erschien darüber hinaus allenfalls in der Anfangsphase geeignet, therapeutische KDntakte bei Therapieunwilligen anzubahnen. Milieutherapeutische Bedingungen im StrafvDllzug waren förderlich für die anfangs auftretenden pO'sitiven Effekte.
No abstract available
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Vogelzwerge des Waldes
(1964)
No abstract available
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Vögel am Roten Meer
(1965)
No abstract available
No abstract available
1. Scorpions can orient menotactically to horizontal air currents (Fig. 1). 2. Changing the wind velocity from 0,05-0,1 m/sec to 3--5 m/sec has no influence on the menotactic angle kept by an anemomenotactic oriented scorpion (Fig. 2). 3. The receptors percieving the direction of air currents are the trichobothria. 4. Orientation to horizon landmarks, anemomenotactic and astromenotactic orientation does not exclude each other but complete themthelves mutually: a) A scorpion orienting to horizon landmarks learns the corresponding anemomenotactic and astromenotactic angle (Fig. 4). b) While orienting anemomenotactically (which is normally the main means of orientation when landmarks are absent) they continously learn new astromenotactical angles (Fig. 5), thus compensating for the movement of the moon or sun which can not be compensated otherwise. c) Short calms and short changes of wind direction can be overcome by astrotaxis.
Werben und Drohen gehören zu den Verhaltensweisen mit Mitteilungswert, die besonders häufig - im Dienste ihrer SignalIunktion umgestaltet - zu Auslösern werden. Solche Auslöser, seien es nun besondere Bewegungsweisen und/oder spezielle morphologische Strukturen, sind an das Individuum gebunden. Eine optische Werbung oder ein Drohen mit körperfremden Mitteln, stellvertretend für ein Individuum, galt bislang als Privileg des Menschen. Die folgenden Ausführungen werden aber zeigen, daß auch andere Lebewesen derartige "Aushängeschilder" gebrauchen.
Insects have evolved an astonishing array of defences to ward off enemies. Well-known and widespread is the regurgitation of oral secretions (OS), fluids that repel attacking predators. In herbivores, the effectiveness of OS has been ascribed so far to the presence of deterrent secondary metabolites sequestered from the host plant. This notion implies, however, that generalists experience less protection on plants with low amounts of secondary metabolites or with compounds ineffective against potential enemies. Resolving the dilemma, we describe a novel defence mechanism that is independent of deterrents as it relies on the OS’ intrinsic detergent properties. The OS of Spodoptera exigua (and other species) was found to be highly amphiphilic and well capable of wetting the hydrophobic cuticle of predatory ants. As a result, affected ants stopped attacking and engaged in extensive cleansing. The presence of surfactants was sufficient to explain the defensive character of herbivore OS. We hypothesize that detergency is a common but unrecognised mode of defence which provides a base level of protection that may or may not be further enhanced by plant-derived deterrents. Our study also proves that insects ‘invented’ the use of defensive surfactants long before modern agriculture had started applying them as insecticides.
Introduction Although symptomatic therapy is available for Parkinson's disease, patients and relatives are faced with continuous severe psychological problems. These psychological problems include: 1. lack of emotional expression, 2. bradephrenia, 3. depression, 4. lack of motivation,S. social anxiety, 6. stress induced increase of symptoms. The first four of these may be at least in part due to the dopamine deficiency. However, even as part of the primary symptoms they have social and communicative impact for patients and relatives. Social anxiety and stress induced increase of symptoms on the other hand clearly result from an interaction of somatic and psychological factors. Social anxiety mainly develops in Parkinson I s disease as an indirect consequence of the motor symptoms. Patients are afraid of being negatively evaluated in the public, of receiving negative comments etc. Thus r social withdrawal increases and the improvement of neurological symptoms following drug treatment may not be fully exploited on the psychosocial level. Stress induced increase of motor symptoms is a commonly observed phenomenon in Parkinson's disease. Even minor stressors, mainly social in nature, can have extreme effects and may elicit or increase tremor or rigidity. A patient can be well in one moment, but unable to move in the next when being aware that he has to leave the house in an hour. Given this situation, patients and relatives have to develop strategies fo~ an emotional balance in the presence of a continuous confrontation with the direct and indirect consequences of the disease. A precondition for developing new psychologically based strategies is an optimwn medical treatment. The integrated approach for neurological and psychological support has the following goals: 1. improving medical treatment for the individual patient, 2. improving psychological coping and psychosocial adaptation for patients and relatives, and 3. evaluating and improving medical and psychological therapy. CONCLUSION Psychological intervention can provide considerable help for a substantial part of Parkinson patients. The main target is coping with stressful social situations. Relaxation and cognitive restructuring together with situational behavioral analysis and training of social skills specifically adapted to the disease are" the main strategies. Various problems remain open at the moment, like the maintenance of motivation which is especially critical for Parkinson patients. Parkins on 's disease is a neurological disease with a known pathological substrate and a therapy which is effective at least for several years on a symptomatic level. The symptoms are tightly connected with psychological emotional and cognitive processes. Moreover, patients and relatives have to cope with symptoms which strongly influence social interaction. And they have to cope together with this situation over a period of ten or twenty years. Thus not only for the patient but also for the health of the relatives, psychological aid is urgently needed. We suggest to integrate psychological approach into the neurological diagnosis and treatment.
Parkinson und Demenz
(1993)
Auf der Delegierten-Konferenz der dPV in Hannover waren eine Reihe von Fragen wr Demenz im Zusammenhang mit dem Morbus Parkinson gestellt worden, zu denen hier Stellung genommen werden soll. Die Fragen und Antworten sind jeweil mit einem ? für die Fragen und einem ! für die Antworten gekennzeichnet.
A video protocolling and retrieval system for the analysis of behaviour. Rec~nt developments in the data processing and video technologies have enabled the desIgn of automatic systems for the handling of video software. The system for the protocoIling and retrieval of audiovisual data (PRA VDA) described here has been developed for applications in behavioural observation and analysis. The facilities available, including time coding, search routines and automatic editing are explained and the advantages of computer aided operation are dealt with. Current applications of the system are briefly discussed.
In this study, the influence of partnership on depression and coping with Parkinson's disease has been investigated. Twentythree single female patients, 46 married patients (23 female, 23 male) with unimpaired partnership and 42 patients (21 female, 21 male) whose partnership had worsened since the onset of disease, were compared with regard to depression and self reported extent of psychosocial distress. Single female patients tended to have higher depression scores than patients in a stable partnership, especially in items concerning personal worthlessness and senselessness of life. Patients differed in the extent of distress concerning social behavior, psychological problems/anxiety and efficiency. Within the group of single female patients two subgroups emerged: (1) patients with low extent of distress in all aspects; (2) patients who were highly distressed by psychological problems and physical disability but weakly distressed from social interaction. Male and female patients living in a stable partnership reported only a generally low to moderate extent of distress. More than half of the male and female patients who reported an impairment of their relationship also had scores of moderate to severe depression. These patients also had the h~ghest extent of distress in each ofthe aspects assessed. The results are dicussed with regard to possible interactive effects ofthe disease, quality of the partnership and availability of coping strategies.
1. Die Feistkäfer Pimelia grossa, P. tenuicornis, der Mehlkäfer Tenebrio molitor, die Mistkäfer Geotrupes silvaticus und G. stercorarius konnen sich unter entsprechenden Bedingungen rein anemomenotaktisch orientieren (Abb. 1-8). Sie bevorzugen Laufwinkel, die in relativ enge Winkelbereiche rechts und links der beiden Grundrichtungen führen (Abb. 3, 4, 26). 2. Die Bevorzugung bestimmter Winkelgrößen andert sich bei Geotrupes nicht gesetzmig mit der Tageszeit, der Temperatur (im Bereich 18-28° C) oder dem Fütterungszustand (Abb. 8-11). 3. Die untere Grenze der Windstärke, die eine menotaktische Einstellung ermöglicht, liegt für die Mistkäfer bei etwa 0,15 m/sec, für die Feistkäfer bei etwa 0,4 m/sec. Die obere Grenze befindet sich bei Geschwindigkeiten, die den Käfern ein Vorwärtskommen unmöglich machen. 4. Bei der menotaktischen Einstellung wird nur die Reizrichtung nicht aber die Reizstarke bewertet (Abb. 13-15). 5. Die Kontinuitat des Luftstroms ist keine Voraussetzung für die anemomenotaktische Orientierung: Die Käfer orientieren sich auch nach kurzen Windstößen (Abb. 17, 19, 21). Während der Windstille kommt es zu regelhaften Abweichungen von dem bei Wind eingehaltenen Kurs (Abb. 18). Das Ausmaß dieser Abweichungen wird nach häufigen Windunterbrechungen stark verringert (Abb. 20). 6. Gegen Turbulenzen des Luftstroms, wie sie über unebenem Untergrund entstehen, ist die Anemomenotaxis der Käfer nicht sehr anfällig (Abb. 22). 7. Die Sinnesorgane, die dem intakten Käfer die Windrichtungsbestimmung ermöglichen, sprechen auf Bewegungen im Pedicellus-Flagellumgelenk an. Ein Verlust der Endkolben hat beim Mistkäfer keinen Einfluß auf die Richtungs- und Winkelgrößenwahl, auch die Streuung wird nicht signifikant größer. 2 Flagellenglieder pro Antenne ermöglichen bei Windgeschwindigkeiten um oder über 1 m/sec noch eine anemomenotaktische Orientierung (Tabelle 3). 8. Bei 3 Mistkäfern, deren Fühler 4 Wochen bzw. 4 Monate vor dem Versuch entfernt worden waren, konnte wieder eine Orientierung nach der Windrichtung nachgewiesen werden (Abb. 23, Tabelle 1). 9. Die Kafer konnen Laufwinkel intramodal vierdeutig transponieren (z.B. Abb. 28, 29). Am deutlichsten tritt diese Fähigkeit bei Versuchsneulingen zutage, deren Laufe rein fluchtmotiviert sind: Sie wählen normalerweise denjenigen der 4 möglichen Laufwinkel, der der Aufsetzrichtung am nächsten liegt (vgl. Abb. 25, 26). 10. Die Existenz und die Wirkungsrichtung eines Drehkommandos, sowie die Beteiligung beider Grundorientierungen an der Anemomenotaxis werden nachgewiesen (Abb. 31). Die Fähigkeit, eine gleichbleibende Drehkommandogröße (die nie zu einer stärkeren Abweichung als 90° von einer Grundrichtung führen kann) mit verschiedenem Vorzeichen der Drehrichtung versehen zu konnen und die Möglichkeit zur Taxisumkehr (Abb. 32) erklären die orientierungsphysiologische Seite des vierdeutigen intramodalen Transponierens. 11. Versuchsergebnisse, die Aussagen uber den physiologischen Mechanismus der Anemomenotaxis der Käfer zulassen, sprechen für einen Kompensationsmechanismus. Die gegen die Kompensationstheorie der Menotaxis (JANDER, 1957) vorgebrachten Argumente werden im Rahmen der bisherigen Resultate kurz diskutiert. 12. Die möglichen biologischen Bedeutungen der Anemomenotaxis werden besprochen. Es wird angenommen, daß sie beim Appetenzverhalten des nach geruchlichen Schlüsselreizen "suchenden" Käfers ihre biologisch wichtigste Aufgabe erfüllt. Sie kann auch die basalen Aufgaben einer Raumorientierung übernehmen und so z.B. kompaßtreue Fluchtkurse steuern.
No abstract available
The effects of 19 meals of different caloric content on slides on palatability and hypothetical duration of consumption were investigated in 7 patients with anorexia nervosa, 17 patients with bulimia nervosa at the beginning and after 8 weeks of hospital treatment. Nine healthy females served as controls. At the beginning of treatment, palatability of low caloric food was significantly higher and hypothetical duration of consumption of high caloric food was significantly longer in patients when compared to controls. After 8 weeks, in the patients palatability of low caloric food had decreased. Dislike for high caloric food remained stable in anorexics.
Fünf Jahre nach der programmatischen Aufforderung von ISRAEL & TAJFEL (1972), mit dem Datensammeln aufzuhören und die theoretische Konfrontation zu suchen, stellt sich die Frage, ob der "Wind der Veränderung" (GRAUMANN, 1975) in der "Europäischen Sozialpsychologie" inzwischen kräftig geblasen hat. Uns interessierte speziell, wie sich heute das Verhältnis von Theorie zu Empirie und von Grundlagen zu Anwendungen einem wohl an Sozialpsychologie interessierten, nicht aber auf Sozialpsychologie spezialisierten deutschen Psychologen darstellt: Ändert sich dieses Verhältnis von "Ost nach West", d.h. von deutschsprachigen über nicht deutschsprachige "europäische" zu "amerikanischen" Veröffentlichungen? Ausserdem fragten wir, ob sich unterschiedliche thematische Sch werpunkte ausfindig machen lassen.
No abstract available
In einem Lemexperiment beurteilten 10 Vpn als Empfiinger die Blicksignale einer Person, die als Sender fungierte. Die Diskriminierungsleistung der Empfanger verbesserte sich als Folge von feedback-Informationen. Die verbesserte Leistung war unabhangig von der Sehscharfe und korrelierte nicht mit Extraversion und Neurotizismus. Fur Zielpunkte des Blicks, die weiter vom Gesicht entfemt waren, war die Leistung am Anfang schlechter und die Leistungsverbesserung ausgepragter. Die Ergebnisse werden im Hinblick auf eine gro6ere Genauigkeit bei der Beobachtung der Variablen 'Blick-Verhalten' diskutiert, was fUr Untersuchungen liber non-verbales Verhalten wichtig ist. FUr Beobachter werden Trainings-Programme vorgeschlagen, bei denen RUckmeldungen liber die tatsachliche Blickrichtung des Senders vermittelt werden konnen. Resume Au cours d'une experience sur l'apprentissage, 10 sujets se comportant comme des recepteurs ont juge les signaux du regard d'un envoyeur. En fournissant de la retroaction quant a la vraie direction du regard on a obtenu un apprentissage dans le sens d'une amelioration de la performance discriminatoire: l'amelioration etait independante de l'acuite visuelle des recepteurs et n'6tait pas correlative a l'extraversion ou au caractere nevrose des sujets. Au debut la performance etait plus mediocre et le progres dans l'apprentissage meilleur dans le cas des points de fixation qui etaient les plus eloignes du visage. On discute des resultats en vue d'ameliorer la precision des observateurs sur la variable 'comportement du regard' important dans les etudes sur la communication nonverbale. On propose un entralnement prealable des observateurs, entrainement qui permet une retroaction explicite quant a la vraie direction du regard.
In zwei Therapieeinrichtungen zur Drogen-Entwöhnungsbehandlung wurde bei 194 Dro- , genabhängigen untersucht, inwiefern Anamnesedaten und Persönlichkeits variablen eine Vorhersage der vorzeitigen Therapiebeendigung gestatten. Lediglich eine Variable wies für Patienten beider Behandlungseinrichtungen gleichermaßen prognostische Valenz auf: Patienten mit gerichtlicher Auflage schlossen die Therapie häufiger regulär ab als Patienten ohne Auflage. Oie Art der gerichtlichen Auflage oder auch die Dauer der noch ausstehenden Strafzeit korrelierten dagegen nicht mit der Art der Therapiebeendigung. Ansonsten gab es für beide Therapieeinrichtungen und für die verschiedenen Arten der vorzeitigen Beendigung (Entlassung bzw. Abbruch) unterschiedliche, manchmal auch entgegengesetzte, prognostische Kriterien. Ein Patient, der in einer Einrichtung abbruchgefährdet ist, kann in einer anderen Einrichtung gute Chancen haben, die Behandlung regulär abzuschließen. Aus der Literatur bekannte Kriterien wie zum Beispiel Alter und Schulbildung zeigten in dieser Studie nur in Abhängigkeit von der Einrichtung prognostische Valenz und dies spezifisch für Abbruch bzw. vorzeitige Entlassung. Andere Prädiktoren wie Geschlecht, psychische Auffälligkeiten und Depression korrelierten überhaupt nicht mit vorzeitiger Therapiebeendigung. Auch Patienten, die zu Beginn der Therapie als gering motiviert einzustufen sind, haben gute Chancen, die Behandlung regulär abzuschließen. Auf der Grundlage einer Diskriminanzanalyse der FPI-Items war eine vorzeitige Entlassung besser vorhersag bar als ein Therapieabbruch. Nach den Daten dieser Studie ist zu vermuten, daß bestimmte Kombinationen von Einrichtungs-, Therapeuten- und Patienten variablen einen Einfluß auf die Art der Therapiebeendigung haben.
1. Bei der Anemomenotaxis arbeiten die Windrichtungen perzipierenden, paarigen Sinnesorgane der Antennen - vermutlich die Johnstonschen Organe - als Synergisten zusammen. Der Ausfall der für die Windrichtung spezifischen afferenten Meldungen eines Fühlers führt zu einer Halbierung der Drehtendenzstärke (Abb.I-ll). Es konnten keine Anhaltspunkte gefunden werden, die auf eine direkte zentrale Kompensation dieses Effektes hinweisen. Verschiedene Arten der Ausschaltung, totalc (Abb.2) oder teilweise (Abb. 4) Amputation (bei der der Pedicellus unverletzt bleibt) oder Blockierung des Pedicellus-Flagellumgelenks durch Lackierung (Abb.3), bewirken dieselben Änderungen im Orientierungsverhalten. 2. Der einzelne Fühler fungiert bei der Anemomenotaxis als "zweisinniger Lenker". Ein Käfer mit nur einem Fühler ist - nach einer genügend langen Erholungszeit - noch fähig, die Windrichtung festzustellen und zu ihr eindeutige menotaktische Kurse zu steuern (vgl. z. B. Abb. 1, 9). Außerdem kann er sich wie ein intakter Käfer (Abb. 14) bei plötzlicher Anderung der Reizrichtung um den kleineren Winkelbetrag zu seiner Sollrichtung zurückdrehen (Abb. 15). 3. Zwischen Drehtendenzstärke und Reizrichtung besteht nach den Ergebnissen der Ausschaltversuche eine Sinusfunktion. Gleichgroße Rechts- oder Linksabweichungen des Käfers von der positiven oder negativen Grundrichtung werden von rechtem und linkem Fühler mit der gleichen Drehtendenzstärke bewertet (Abb. 13). Es ist deshalb naheliegend, anzunehmen, daß jeder Fühler bei der Reizrichtungsbewertung seinen Abweichungsbetrag von der nächsten der beiden Grundstellungen mißt. In einer Grundstellung befindet sich der Fühler jeweils dann, wenn sich der Käfer genau gegen oder mit dem Wind eingestellt hat. 4. Afferente Drehtendenz und efferentes Drehkommando sind Dreherregungsgrößen, die sich bei Einstellung des Sollwinkels durch ihre antagonistische Wirkung aufheben. Halbierung der Drehtendenzstärke durch Ausschaltung eines Fühlers führt demnach erwartungsgemäß zu einer Verdopplung der Drehkommandowirkung. Daraus und aus der Sinusförmigkeit der Drehtendenzstärkenkurve ergibt sich, daß Drehkommandogrößen, die beim intakten Käfer die Einhaltung von Menotaxiswinkeln von > 30° zur Folge haben, von der halbierten Drehtendenz nicht mehr kompensiert werden können. Die Käfer können dann Dauerrotationen vermeiden, indem sie das Drehkommando soweit abschwächen, daß es von der halbierten Drehtendenz wieder kompensiert wird (Abb. 8). 5. Standardabweichung und mittlere Laufwinkelgröße sind miteinander korreliert. Die Korrelation gilt in gleicher Weise für das intakte und das einseitig antennenamputierte Versuchstier. 6. Nach einer einseitigen Fühlerausschaltung bevorzugen Tenebrio molitor und Scaurus dubius anfänglich Laufrichtungen zur Seite der intakten Antenne hin. Bei allen VT-Arten nimmt die Neigung zum intramodalen Winkeltransponieren nach Fühlerausschaltung sehr stark zu (Abb. 12). 7. Den Grundorientierungen - positive und negative Anemotaxis - liegt, wie auch der Menotaxis, kein tropotaktischer Mechanismus der Fühlerverschaltung zugrunde. Anemotaxis und Anemomenotaxis unterscheiden sich lediglich dadurch, daß bei letzterer ein efferentes Drehkommando die Sollrichtung verstellt. 8. Die experimentellen Befunde werden im Hinblick auf den, der Anemomenotaxis zugrunde liegenden, physiologischen Mechanismus diskutiert: Sie lassen sich alle widerspruchslos mit einem Kompensationsmechanismus vereinen.
Unter den Krebsen ist als größerer Gruppe allein den Landasseln (Oniscoidea) eine Eroberung des Festlandes gelungen. Ihre Anpassung an das Landleben blieb aber bislang recht mangelhaft, z. B. fehlt ein wirksamer Verdunstungsschutz. Wie zu erwarten, bewohnen daher die meisten Landasselarten feuchte Lebensstätten. Zu den wenigen Ausnahmen zählt die Wüstenassel Hemilepistus reaumuri, die nordafrikanische und kleinasiatische Halbwüsten - stellenweise auch echte Wüstengebiete - besiedelt. Es sind vor allem Verhaltensanpassungen, die den Wüstenasseln in diesen während vieler Monate trockenheißen Extrembiotopen nicht nur ein Oberleben erlauben, sondern sie darüber hinaus noch vielerorts zum erfolgreichsten Faunenelement machen.
No abstract available
A novel chromatin configuration is described in lampbrush chromosomes of Pleurodeles waltlii oocytes which is different from transcriptionally inactive chromatin as weil as from the various forms of transcribed chromatin hitherto described. This novel type of chromatin is not arranged in Christmas tree-Iike configurations of densely packed lateral ribonucleoprotein (RNP) fibriIs but is characterized by a periodic alternating pattern of thick and thin regions which occur in clusters 01 some 10,000 repeats. Each thickened unit with an average length of 45 nm contains two c10sely spaced particles, the putative RNA polymerases, and each thickened unit is separated from the next one by a beaded chromatin spacer with a length of about 80 nm. This chromatin spacer contains on average two particles of approximately 14 nm in diameter, assumed to be nucleosomes. The thickened regions are interpreted to represent short transcriptional units containing approximately 130 base pairs of DNA which are separated from each other by nontranscribed spacers of 240-400 base pairs of DNA. The possibility is discussed that these transcriptional units represent 5S rRNA or tRNA genes.
No abstract available
No abstract available
This paper describes the influence of neuroleptic therapy on facial action in drug-naive schizophrenics. In a comparative study of medicated and unmedicated schizophrenic patients, the coordinates of 12 small light-reflecting points, attached to subjects' faces, were computer-recorded and analyzed automatically during a semistandardized clinical interview. In addition, facial activity in videotaped interviews was coded using the Facial Action Coding System (FACS). Each sample group comprised of eight patients with the DSMIII- R diagnostic criteria "schizophrenia" or "schizophreniform disorder". Subjects were studied on two occasions, one shortly after admission to the hospital, the other three weeks later. Group I was unmedicated during the first session, whereas group2 was medicated throughout the study. Three weeks after the start of medication, at the second interview, both recording methods showed a reduction in facial activity and facial expression across all subjects in group 1. The facial action of patients in group2, however, remained unchanged.
Es wird gezeigt, daß die digitale Sprachanalyse bei der Messung von Sprechpausen unter bestimmten Umständen Fehler aufweist. Am Beispiel von 16 standardisierten Interviews mit depressiven Patienten wurden Sprechpausen von Patienten und Interviewern nach zwei Methoden gemessen: mit einer einfachen manuellen Methode deren Interraterreliabilität bei .88 und höher lag und nach Methoden der digitalen Sprachverarbeitung. Die Ergebnisse beider Analysen wurden verglichen. Dabei zeigte sich, daß die manuelle Methode für Sprechpausen oberhalb 390 ms reliabel ist und gleiche oder bessere Ergebnisse bringt. Bei qualitativ schlechten Tonaufnahmen ist diese manuelle Methode vorteilhaft.
Nonverbal behavior, especially facial expression, appears as one of the most important means for communicating affective states. Studies on groups of psychiatric patients and control subjects are reported in which nonverbal behavior is analyzed from videotaped dialogues. Using a quantitative approach, results on facial behavior, speech, and gaze are described, which shed light on the expressive and communicative functions of nonverbal behavior. From longitudinal observations on depressed patients it emerged that individualspecific associations have to be taken into account for the relationship between expressive behavior and mood changes. The predominance of facial behavior in the speaker role of an individual found in patients and control groups points to the integrated communicative function of the verbal and nonverbal elements. However, recovered schizophrenic patients exhibited a dissociation of these elements. Implications for our understanding of nonverbal communications are discussed.
A rapid method for macroscopic and microscopic investigation of human CNS is proposed. After fonnalin fixation, gelatin or agarose embedding, and cryoprotective treatment, frozen human spinal cords, brainstems, or hemispheres can be serially cut into 0.7 mm thick slices. Stained with gallocyanin-chromalum, these slices facilitate cytoarchitectonic, neuropathologic, and quantitative examination. Regions of interest from parallel fonnalin-stored unstained slices can be embedded into paraffin and stained by any irnrnunocytologic and histologic stain compatible with fonnalin fixation and paraffin embedding.
Foliation of the cerebella of Sprague-Dawley rats (strain Han:SPRD) is more advanced than in Wistar rats (strain Chbb:THOM). The differences expressed as length of the granular layer in median sections were significant in lobules VIa, VIII, IX and X. The length of the other vermian lobules is generally higher in the former strain. With regard to the volume of the granular layer, the situation is reversed, indicating that the lateral extent and thickness of vermian lobules in Wistar rats (strain Chbb:THOM) is generally larger. These quantitative differences may express differences in cerebellar microcircuitry and fibre connections in the cortex of Wistar and Sprague-Dawley rats.
Validität und Reliabilität der Sprechkodierung einer Beobachtergruppe wurden in Abhängigkeit von der zeitlichen Auflösung untersucht. Die Validität wurde anhand der Übereinstimmung der Beobachter mit einem automatischen Sprachdetektor berechnet. Die Reliabilitätswerte für die Kodierung von Sprechen und Blikken ergaben sich aus der Übereinstimmung der Beobachter untereinander. Im wesentlichen zeigten sich folgende Ergebnisse: 1. Die Validität/Reliabilität der Sprechkodierung ist eine monotone, nichtlineare Funktion der gewählten Auflösung. Die systematischen Fehler, die auf Latenz und Trägheit der menschlichen Beobachter zurückgehen, werden bei einer Auflösung von 400 msec nahezu vollständig unterdrückt. 2. Weder bei der Erfassung des Sprech- noch des Blickverhaltens lassen sich Anzeichen für Observer-Drift feststellen. Trainierte und untrainierte Beobachter unterscheiden sich nicht signifikant. 3. Die Kodierung des Sprechverhaltens ist geringfügig reliabler als die des Blickverhaltens. Dieser Unterschied kann in der Praxis vernachlässigt werden.
Die Wirksamkeit des Modellernens im Klassenzimmer zur Veränderung der Prüfungsangst wurde bei 152 Knaben und 164 Mädchen der Klassen 5-8 einer Hauptschule untersucht. Den Schülern wurden die Angst-Skalen (TASe und GASC) von Sarason vorgelegt. Anhand der Fragebogenergebnisse wurden die Kinder den Kategorien "hochängstlich" (HA), "mittelängstlich" (MA) und "niedrigängstlich" (NA) zugeordnet. Für 3,5 Monate wurden die folgenden Paarbildungen (Banknachbarn) beibehalten: HA neben HA, MA und NA, NA neben NA und MA, sowie MA neben MA. Signifikante Verringerungen der Prüfungsangst ergaben sich bei hochängstlichen Schülern, die neben niedrig- bzw. mittelängstlichen Schülern saßen. Modellernen scheint ein praktikabler Weg zu sein, in der Schulsituation gezielt Prüfungsangst zu verringern.
An ordered NotI fragment map containing over 60 loci and encompassing approximately 17 Mb has been constructed for human chromosome band llpl5. Forty-two probes, including 11 NotI-linking cosmids, were subregionaUy mapped to llpl5 using a subset of the Jl-deletion hybrids. These and 23 other probes defining loci previously mapped to 11p15 were hybridized to genomic DNA digested with NotI and 5 other infrequently cleaving restriction enzymes and separated by pulsed-field gel electrophoresis. Thirty-nine distinct NotI fragments were detected encompassing approximately 85% of the estimated length of llp15. The predicted order of the gene loci used is cenMYODI- PTH-CALCA-ST5-RBTNI-HPX-HBB-RRMlTH/ INS!1GF2-H19-CTSD-MUC2-DRD4-HRAS-RNHtel. This map wiu allow higher resolution mapping of new Ilp15 markers, facilitate positional cloning of disease genes, and provide a framework for the physical mapping of llp15 in clone contigs.
The total number and the number of Purkinje cells per square millimeter of the surface of the cerebellar granular layer were measured in albino rats from two strains: Chbb-THOM-Wist and Han: SPRD. The total number of the Purkinje cells in the cerebellar vermian lobules L land L X with the exception of cells in the lobules VIb + c did not. differ significantly. Statistically significant differences were found between the individuals of the two rat strains and within single lobules of the cerebella concerning the cell density of Purkinje cells per square millimeter surface of the granular layer. The results suggest heterogeneity of the cerebellar cortex between cerebellar lobules and between albino rats derived from different strains.
PtK2 cells in which pore complex-mediated transport is blocked by microinjection early in mitosis of a monoclonal antibody (specific for an Mr 68000 pore complex glycoprotein) or of wheat germ agglutinin (WGA) complete cytokinesis. However, their nuclei remain stably arrested in a telophase-like organization characterized by highly condensed chromatin and the absence of nucleoli, indicating a requirement for pore-mediated transport for the reassembly of interphase nuclei. We have now examined this requirement more closely by monitoring the behavior of individual nuclear macromolecules in microinjected cells using immunofluorescence microscopy and have investigated the effect of microinjecting the antibody or WGA on cellular ultrastructure. The absence of nuclear transport did not affect the sequestration into daughter nuclei of components such as DNA, DNA topoisomerase I and the nucleolar protein fibrillarin that are carried through mitosis on chromosomes. On the other hand, lamins, snRNAs and the p68 pore complex glycoprotein, all cytoplasmic during mitosis, remained largely cytoplasmic in the telophase-arrested cells. Electron microscopy showed the nuclei to be surrounded by a doublelayered membrane with some inserted pore complexes. In addition, however, a variety of membranous structures with associated pore complexes was regularly noted in the cytoplasm, suggesting that chromatin may not be essential for the postmitotic formation of pore complexes. We propose that cellular compartmentalization at telophase is a two-step process. First, a nuclear envelope tightly encloses the condensed chromosomes, excluding non-selectively all macromolecules not associated with the chromosomes. Interphase nuclear organization is then progressively restored by selective pore complex-mediated uptake of nuclear proteins from the cytoplasm.
No abstract available
No abstract available
The arrangement of genes of precursor molecules for ribosomal RNA (pre-rRNA) in primary nuclei from two green algae species, Acetabularia mediterranea and A. major, has been analyzed in an electron microscope study. The pattern of transcriptional units in individual strands of nucleolar chromatin was investigated using spread and positively stained preparations. The rDNA pattern is not uniform but differs in different strands. The predominant type of nucleolar chromatin exhibits a high degree of homogeneity in the sequence of matrix units (intercepts covered with fibrilst hat contain the pre-rRNA) and fibril-free spacer intercepts. Substantial differences, however, are observed between the patterns in different strands. In addition, there is evidence in some strands for intraaxial heterogeneity of both spacer and matrix units. The following major types can be distinguished: type la, ca. 2 micrometer long matrix units, extremely short spacer intercepts in A. mediterranea (ca. 1 micrometer long ones in A. major), completely homogeneous distribution; type Ib, as type la but with intercalated, isolated, significantly shorter and/or longer matrix units; type lIa, matrix unit sizes as in type la, but much longer spacer intercepts, high degree of homogeneity; type Ill, largely heterogeneous arrangements of matrix and spacer units of varying sizes. The matrix unit data are compared with the sizes of pre-rRNA as determined by polyacrylamide gelelectrophoresis under denaturing and non-denaturing conditions. The findings are discussed in relation to recent observations in amphibia and insects and with respect to current concepts of the species-specificity of rDNA arrangements.
Antibody against tubulin from porcine brain was used to evaluate the immunological cross reactivity of tubulin from a variety of animal and plant cells. Indirect immunofluorescence microscopy revealed microtubule-containing structures including cytoplasmic microtubules, spindle microtubules, cilia and fIagella. Thus tubulin from diverse species of both mammals and plants show immunological cross-reactivity with tubulin from porcine brain. Results obtained by immunofluorescence microscopy are whenever possible compared with previously known ultrastructural results obtained by electron microscopy.
The organization of the extrachromosomal nucleolar material in oocytes of two insect species with different ovary types, the house cricket Acheta domesticus (panoistic ovary) and the water beetle Dytiscus marginalis (meroistic ovary), was studied with light and electron microscopic techniques. Stages early in oogenesis were compared with fully vitellogenic stages (mid-to-Iate diplotene). The arrangement of the nucleolar material undergoes a marked change from a densely aggregated to a dispersed state. The latter was characterized by high transcriptional activity. In spread and positively stained preparations of isolated nucleolar material, a high frequency of small circular units of transcribed rDNA was observed and rings with small numbers (1-5) of pre-rRNA genes were predominant. The observations suggest that the "extra DNA body" observed in early oogenic stages of both species represents a dense aggregate of numerous short circular units of nucleolar chromatin, with morphological subcomponents identifiable in ultrathin sections. These apparently remain in close association with the chromosomal nucleolar organizer(s). The observations further indicate that the individual small nucleolar subunit circles dissociate and are dispersed as actively transcribed rDNA units later in diplotene. The results are discussed in relation to principles of the ultrastructural organization of nucleoli in other cell types as well as in relation to possible mechanisms of gene amplification.
The morphology of two forms of transcription ally active chromatin, the nucleoli and the loops of lampbrush chromosomes, has been examined after fixation in situ or after isolation and dispersion of the material in media of low ionic strengths, using a variety of electron microscopic preparation techniques (e.g. spread preparations with positive or negative staining or without any staining at all, with bright and dark field illumination, with autoradiography, after pretreatment of the chromatin with specific detergents such as Sarkosyl NL-30; transmission and scanning transmission electron microscopy of ultrathin sections). Nucleolar chromatin and chromosomes from oocytes of various amphibia and insects as well as from green algae of the family of the Dasycladaceae were studied in particular detail. The morphology of transcriptional units that are densely packed with lateral ribonucleoprotein fibrils, indicative of great transcriptional activity, was compared with that of chromatin of reduced lateral fibril density, including stages of drug-induced inhibition. The micrographs showed that under conditions which preserve the nucleosomal organization in condensed chromatin studied in parallel, nucleosomes are not recognized in transcriptionally active chromatin. This holds for the transcribed regions as well as for apparently untranscribed (i.e. fibril-free) regions interspersed between ('spacer') and/or adjacent to transcribed genes and for the fibril-free regions within transcriptional units of reduced fibril density. In addition, comparison oflengths of repeating units of isolated rDNA with those observed in spread nucleolar chromatin indicated that this DNA is not foreshortened and packed into nucleosomal structures. Granular particles which were observed, at irregular frequencies and in variable patterns, in some spacer regions, did not result in a proportional shortening of the spacer axis, and were found to be resistant to detergent treatment effective in removing most of the chromatin associated proteins including histones. Thus, these particles behave like RNA polymerases rather than nucleosomes. It is suggested that structural changes from nucleosomal packing to an extended form of DNA are involved in the transcriptional activation of chromatin.
Available data on the occurrence and expression of somatic histone HI during oogenesis and early embryogenesis of Xenopus laevis are contradictory. In particular the reported presence of a large storage pool of histone HIA in oocytes is difficult to reconcile with the high transcriptional activity of all gene classes in this specific cell type. In the present study we have used polyclonal antibodies raised against somatic Xenopus histone HI (HIA and HIA/B) for combined immunoblotting experiments to quantitate HI pools and immunolocalization studies to visualize chromosome- bound HI. Both approaches failed to detect soluble or chromosomal histone HI in vitellogenic oocytes, eggs, and cleavage-stage embryos up to early blastula. In addition, chromatin assembled in Xenopus egg extract was also negative for histone HI as revealed by immunofluorescence microscopy. Lampbrush chromosomes not only lacked histone HI but also the previously identified histone HI-like B4 protein (Smith et al., 1988, Genes Dev. 2,1284-1295). In contrast, chromosomes of eggs and early embryos fluoresced brightly with anti-B4 antibodies. Our results lend further support to the view that histone HI expression is developmentally regulated during Xenopus oogenesis and embryogenesis similar to what is known from other species.
Nach homoplastischer Transplantation von larvalen Gonaden mit Fettkiirper in die vordere Leibeshiihle wiichst nur der Fettkiirper an der Leber an, so daB die Gonade nur indirekt mit dem Wirtsgewebe verbunden ist. Die Differenzierung der Gametogonien folgt der Normogenese, bei Ovartransplantationen entwickeln sich Auxocyten. Nach spatestens 27 Tagen ist die Blutversorgung wiederhergestellt. Homo- und autoplastische Transplantationen von Gonaden oh ne Fettkiirper ergeben fUr die Gametogonien eine vollig andere Entwicklung. Sind die Gonaden mit breiter Fliiche angewachsen, liiBt si ch bereits 7 Tage p.o. im Bereich der Kontaktzone Gonade-Leber die Karyolyse der Gametogonienkerne feststellen. Nach 3--4 Wochen stellt das Transplantat eine bindegewebige Zyste ohne Geschlechtszellen dar. Erythrozyten zeigen die Vaskularisation an. 1st nur ein Teil der Gonade mit der Leber verwachsen, zeigt der frei gebliebene Abschnitt eine normale Struktur mit Mitosen der Gametogonien. Die Degeneration der Geschlechtszellen hiingt offenbar von ihrer Lage zum extragonadalen Gewebe ab.
Transcribed nucleolar chomatin, including the spacer regions interspersed between the rRNA genes, is different from the bulk of nontranscribed chromatin in that the DNA of these regions appears to be in an extended (B) conformation when examined by electron microscopy. The possibility that this may reflect artificial unfolding of nucleosomes during incubation in very low salt buffers as routinely used in such spread preparations has been examined by studying the influence of various ion concentrations on nucleolar chromatin structure. Amplified nucleolar chromatin of amphibian oocytes (Xenopus laevis, Pleurodeles waltlii, Triturus cristatus) was spread in various concentrations of NaCl (range 0 to 20 mM). Below 1 mM salt spacer chromatin frequently revealed a variable number of irregularly shaped beads, whereas above this concentration the chromatin axis appeared uniformly smooth. At all salt concentrations studied, however, the length distribution of spacer and gene regions was identical. Preparations fixed with glutaraldehyde instead of formaldehyde, or unftxed preparations, were indistinguishable in this respect. The observations indicate that (i) rDNA spacer regions are not compacted into nucleosomal particles and into supranucleosomal structures when visualized at chromatin stabilizing salt concentrations (e.g., 20 mM NaCl), and (ii) spacer DNA is covered by a uniform layer of proteins of unknown nature which, at very low salt concentrations (below 1 mM NaCl), can artificially give rise to the appearance of small granular particles of approximately nucleosome-like sizes. These particles, however, are different from nucleosomes in that they do not foreshorten the associated spacer DNA. The data support the concept of an altered nucleohistone conformation not only in transcribed chromatin but also in the vicinity of transcriptional events.
High sensitivity immunolocalization of double and single-stranded DNA by a monoclonal antibody
(1987)
A monoclonal antibody (AK 30-10) is described which specifically reacts with DNA both in double and single-stranded forms but not with other molecules and structures, including deoxyribonucleotides and RNAs. When used in immunocytochemical experiments on tissue sections and permeabilized cultured cells, this antibody detects DNA-containing structures, even when the DNA is present in very small amounts. Examples of high resolution detection include the DNA present in amplified extrachromosomal nucleoli, chromomeres of lampbrush chromosomes, mitochondria, chloroplasts and mycoplasmal particles. In immunoelectron microscopy using the immunogold technique, the DNA was localized in distinct substructures such as the "fibrillar centers" of nucleoli and certain stromal centers in chloroplasts. The antibody also reacts with DNA of chromatin of living cells, as shown by microinjection into cultured mitotic cells and into nuclei of amphibian oocytes. The potential value and the limitations of immunocytochemical DNA detection are discussed.
No abstract available
Dications 1 derived from 2,2-bipyridine are found to exist as fully reversible two step redox systems with persistent radical ions (SEM) of high thermodynamic stability, if the bridge X forces the two pyridine rings into co planar positions. The well known derivative 1a (Diquat R) is now complemented by the boronium ions 1c and 1e -1g., as shown by voltammetry and the uv spectra of the corresponding radicals.
Using a monoclonal antibody (No-194) we have identified, in Xenopus laevis and other amphibia, an acidic protein of M, 40,000 (ribocharin) which is specifically associated with the granular component of the nucleolus and nucleoplasmic 65S particles. These particles contain the nuclear 28S rRNA and apparently represent the precursor to the large ribosomal subunit in nucleocytoplasmic transit. By immunoelectron microscopy ribocharin has been localized in the granular component of the nucleolus and in interchromatin granules. During mitosis ribocharin-containing particles are associated with surfaces of chromosomes and are recollected in the reconstituting nucleoli in late telophase. We suggest that ribocharin is a specific component of precursor particles of the large ribosomal subunit, which dissociates from the 65S particle before passage through the nuclear envelope, and is reutilized in ribosome biogenesis.
A non-radioactive in situ hybridization method is described for the localization of transcription units of defined genes to lateral loops of Xenopus laevis lampbrush chromosomes. Two Xenopus cONA probes were used encoding the nucleolar protein N038/ B23 and cytokeratin 1(8). Both proteins are known to be synthesized in Xenopus oocytes, and Northern blot analysis revealed the presence of the corresponding mRNAs in different oogenic stages. The probes were enzymatically labeled with biotin-dCTP and hybridized to lampbrush chromosomes. The sites of hybridization were detected either by indirect immunofluorescence microscopy using rabbit antibodies against biotin and fluorescein-conjugated antirabbit IgG or enzymatically using peroxidase-conjugated streptavi din. The probe encoding the nucleolar protein hybridized to two sets of lateral loops on different bivalents, the cytokeratin probe to at least four. Our finding that each probe hybridized to more than one chromosomal locus may reflect the tetraploid nature of the Xenopus laevis genome or results from cross-hybridization to other transcriptionally active members of the N038/ B23-nucleoplasmin or the cytokeratin-Iamin gene families. The method described should facilitate further in situ hybridization studies with appropriate genomic clones in order to map specific DNA sequences to defined loop regions and to come to a better understanding of the relationship between loop organization and gene transcription unit.
Many nuclear proteins are released into the cytoplasm at prometaphase and are transported back into the daughter nuclei at the end of mitosis. To determine the role of this reentry in nuclear remodelling during early interphase, we experimentally manipulated nuclear protein uptake in dividing cells. Recently we and others have shown that signal-dependent, pore complex-mediated uptake of nuclear protein is blocked in living cells on microinjection of the lectin wheat germ agglutinin (WGA), or of antibodies such as PI1 that are directed against WGA-binding pore complex glycoproteins. In the present study, we microinjected mitotic PtKz cells with WGA or antibody PIt and followed nuclear reorganization of the daughter cells by immunofluorescence and electron microscopy. The inhibitory effect on nuclear protein uptake was monitored by co-injection of the karyophilic protein nucleoplasmin. When injected by itself early in mitosis, nucleoplasmin became sequestered into the daughter nuclei as they entered telophase. In contrast, nucleoplasmin was excluded from the daughter nuclei in the presence of WGA or antibody PI1 . Although PtKz cells with blocked nuclear protein uptake completed cytokinesis, their nuclei showed a telophaselike organization characterized by highly condensed chromatin surrounded by a nuclear envelope containing a few pore complexes. These findings suggest that pore complexes become functional as early as telophase, in close coincidence with nuclear envelope reformation. They further indicate that the extensive structural rearrangement of the nucleus during the telophase-G1 transition is dependent on the influx of karyophilic proteins from the cytoplasm through the pore complexes, and is not due solely to chromosome- associated components.
In order to investigate the DNA localization within Ehrlich tumor cell nucleoli during mitosis, two recent immunocytochemical methods using either an anti-DNA or an anti-bromodeoxyuridine (BrdU) monoclonal antibody have been applied. In both cases, the immunogold labeling has been performed on ultrathin sections of cells embedded either in Lowicryl K4M or in Epon, respectively. Identical results are observed with both immunocytochemical approaches. In the interphase nucleolus, besides the labeling of the perinucleolar chromatin shell and of its intranucleolar invaginations which penetrate into the nucleolar body and often terminate at the fibrillar centers, a few gold particles are also preferentially found towards the peripheral region of the fibrillar centers. In contrast, the dense fibrillar component and the granular component are never labeled. During mitosis, the fibrillar centers persist at the chromosomal nucleolus organizing regions (NOR's) and can be selectively stained by the silver method. However, these metaphase fibrillar centers are no longer decorated by the DNA- or BrdU antibodies. These results indicate that until the end of prophase, rRNA genes are present inside the fibrillar center material, disappear during metaphase and reappear in reconstituting nucleoli during telophase. Thus, fibrillar centers appear to represent structures sui generis, which are populated by rRNA genes only when the nucleolus is functionally active. In segregated nucleoli after actinomycin D treatment, the DNA labeling is exclusively restricted to the perinucleolar chromatin blocks. These findings also suggest that the DNA content of the fibrillar center material varies according to the rRNA transcription level of the cells. The results are discussed in the light of the present knowledge of the functional organization of the nucleolus.
Motoneurons innervating the skeletal musculature were among the first neurons shown to require the presence of their target cells to develop appropriatelyl,2. But the characterization of molecules allowing motoneuron survival has been difficult. Ciliary neurotrophic factor prevents the death of motoneurons3-6, but its gene is not expressed during development7. Although the presence of a neurotrophin receptor on developing motoneurons8-1O has suggested a role for neurotrophins, none could be shown to promote motoneuron survival in vitro3. We report here that brainderived neurotrophic factor can prevent the death of axotomized motoneurons in newborn rats, suggesting a role for this neurotrophin for motoneuron survival in vivo.
We have been studying a population of bipotential glial progenitor cells in the perinatal rat optic nerve and brain in an attempt to understand how cells choose between alternative fates in the developing mammalian central nervous system (CNS). This cell population gives rise initially to oligodendrocytes and then to type-2 astrocytes1 both of which apparently collaborate in sheathing axons in the CNS2,3. In vitro studies suggest that oligodendrocyte differentiation is the constitutive pathway of development for the oligodendrocyte-type-2-astrocyte (O-2A) progenitor cell4,5, whereas type-2 astrocyte differentiation depends on a specific inducing protein6. This protein is present in the developing optic nerve when type-2 astrocytes are differentiating and can induce 0-2A progenitor cells in vitro to express glial fibrillary acidic protein (GFAP)6, a marker of astrocyte differentiation7. Here we show that the type-2-astrocyte-inducing protein is similar or identical to ciliary neutrotrophic factor (CNTF)8,9, which promotes the survival of some types of peripheral neurons in vitro8, including ciliary ganglion neurons8,10. This suggests that CNTF, in addition to its effect on neurons, may be responsible for triggering type-2 astrocyte differentiation in the developing CNS.
No abstract available
The survival and functional maintenance of spinal motoneurons, both during the period of developmental cell death and in adulthood, have been shown to be dependent on trophic factors. In vitro experiments have previously been used to identify several survival factors for motoneurons, including CNTF, UF, and members of the neurotrophin, FGF, and IGF gene families. Some of these factors have also been shown to be active in vivo, either on chick motoneurons during embryonic development or on lesioned facial and spinal motoneurons of the newborn rat. Here we demonstrate that lesioned newborn rat facial motoneurons can be rescued by NT-4/5, IGF-I, and UF. Furthermore, in contrast to chick motoneurons, the survival of isolated embryonic rat motoneurons can be maintained by the neurotrophins BDNF, NT-3, and NT-4/5. IGF-I and FGF-5 were also active in this system, each supporting more than 50% of the originally plated neurons. The responsiveness of motoneurons to multiple factors in vitro and in vivo suggests that motoneuron survival and function are regulated by the coordinated actions of members of different gene families.
After microinjection of antibodies against RNA polymerase I into the nuclei of cultured rat kangaroo (PtKz) and rat (RVF-SMC) cells alterations in nucleolar structure and composition were observed. These were detected by electron microscopy and double-label immunofluorescence microscopy using antibodies to proteins representative of the three major components of the nucleolus. The microinjected antibodies produced a progressive loss of the material of the dense fibrillar component (DFC) from the nucleoli which, at 4 h after injection, were transformed into bodies with purely granular component (GC) structure with attached fibrillar centers (FCs). Concomitantly, numerous extranucleolar aggregates appeared in the nucleoplasm which morphologically resembled fragments of the DFC and contained a protein (fibrillarin) diagnostic for this nucleolar structure. These observations indicate that the topological distribution of the material constituting the DFC can be experimentally influenced in interphase cells, apparently by modulating the transcriptional activity of the rRNA genes. These effects are different from nucleolar lesions induced by inhibitory drugs such as actinomycin D-dependent "nucleolar segregation". The structural alterations induced by antibodies to RNA polymerase I resemble, however, the initial events of nucleolar disintegration during mitotic prophase.
We showed previously that oligodendrocytes and their precursors require continuous signalling by protein trophic factors to avoid programmed cell death in culture. Here we show that three classes of such trophic factors promote oligodendrocyte survival in vitro: (1) insulin and insulin-like growth factors (IGFs), (2) neurotrophins, particularly neurotrophin-3 (NT -3), and (3) ciliary-neurotrophic factor (CNTF), leukemia inhibitory factor (LIF) and interleukin 6 (IL-6). A single factor, or combinations of factors within the same class, promote only short-term survival of oligodendrocytes and their precursors, while combinations of factors from different classes promote survival additively. Long-term survival of oligodendrocytes in vitro requires at least one factor from each class, suggesting that multiple signals may be required for long-term oligodendrocyte survival in vivo. We also show that CNTF promotes oligodendrocyte survival in vivo, that platelet-derived growth factor (PDGF) can promote the survival of oligodendrocyte precursors in vitro by acting on a novel, very high affinity PDGF receptor, and that, in addition to its effect on survival, NT-3 is a potent mitogen for oligodendrocyte precursor cells.
The cDNA for ciliary neurotrophic factor (CNTF), a polypeptide involved in the survival of motoneurons in mammals, has recently been cloned (Stöckli et al., Nature, 342, 920 - 923, 1989; Lin et al. Science, 246, 1023 - 1025, 1989). We have now localized the corresponding gene Cntf to chromosome 19 in the mouse, using an interspecific cross between Mus spretus and Mus musculus domesticus. The latter was carrying the gene wobbler (wr) for spinal muscular atrophy. DNA was prepared from backcross individuals and typed for the segregation of species-specific Cntf restriction fragments in relation to DNA markers of known chromosomal location. The M.spretus allele of Cntf cosegregated with chromosome 19 markers and mapped closely to Ly-1, to a region of mouse chromosome 19 with conserved synteny to human chromosome 11q. Cntf is not linked to wr, and the expression of CNTF mRNA and protein appears close to normal in facial and sciatic nerves, of affected (wr/wr) mice, suggesting that motoneuron degeneration of wobbler mice has its origin in defects other than reduced CNTF expression.
The ability of nerve growth factor to cause rapid activation of the Na+K+ pump of its responsive cells was examined by measuring the uptake of 86Rb+. A significant increase in 86Rb+ uptake in Ea chick dorsal root ganglion sensory neurons after NGF treatment was seen only if the cells had been damaged during the preparation procedure. Such damaged cells could not survive in culture in the presence of NGF, and undamaged cells that did survive in response to NGF exhibited no increased 86Rb+ uptake rate. Furthermore, cultured calf adrenal medullary cells did not show an increase in 86Rb+ uptake after treatment with NGF, although these cells respond to NGF with an increased synthesis of catecholaminergic enzymes. These results are incompatible with the hypothesis that the mechanism of action of NGF that promotes neuronal survival and enzyme induction results from an initial stimulation of the Na+K+ pump.
0-2A progenitor cells give rise to both oligodendrocytes and type-2 astrocytes in vitro. Whereas oligodendrocyte differentiation occurs constitutively, type-2 astrocyte differentiation requires extracellular signals, one of which is thought to be ciliary neurotrophic factor (CNTF). CNTF, however, is insufficient by itself to induce the development of stable type-2 astrocytes. In this report we show the following: (a) that molecules associated with the extracellular matrix (ECM) cooperate with CNTF to induce stable type-2 astrocyte differentiation in serumfree cultures. The combination of CNTF and the ECM-associated molecules thus mimics the effect of FCS, which has been shown previously to induce stable type-2 astrocyte differentiation in vitro. (b) Both the ECM-associated molecules and CNTF act directly on 0-2A progenitor cells and can induce them to differentiate prematurely into type-2 astrocytes. (c) ECM-associated molecules also inhibit oligodendrocyte differentiation, even in the absence of CNTF, but this inhibition is not sufficient on its own to induce type-2 astrocyte differentiation. (d) Whereas the effect of ECM on oligodendrocyte differentiation is mimicked by basic fibroblast growth factor (bFGF), the effect of ECM on type-2 astrocyte differentiation is not. (e) The ECM-associated molecules that are responsible for inhibitin~ oligodendrocyte differentiation and for cooperating with CNTF to induce type-2 astrocyte differentiation are made by non-glial cells in vitro. (f) Molecules that have these activities and bind to ECM are present in the optic nerve at the time type-2 astrocytes are thought to be developing.
More on motor neurons
(1992)
The ultrastructure of twO kinds of transcription ally active chromatin, the lampbrush chromosome loops and the nucleoli from amphibian oocytes and primary nuclei of the green alga Acetabularia, has been examined after manual isolation and dispersion in low salt media of slightly alkaline pH using various electron microscopic staining techniques (positive staining, metal shadowing, negative staining, preparation on positively charged films, etc.) and compared with the appearance of chromatin from various somatic cells (hen erythrocytes, rat hepatocytes, ClIltured murine sarcoma cells) prepared in parallel. While typical nucleosomes were revealed with all the techniques for chromatin from the latter three cell system, no nucleosomes were identified in either the lampbrush chromosome structures or the nucleolar chromatin. Nucleosomal arrays were absent not only in maximally fibril-covered matrix units but also in fibril-free regions between transcriptional complexes, including the apparent spacer intercepts between different transcriptional units. Moreover, comparisons of the length of the repeating units of rDNA in the transcribed state with those determined in the isolated rDNA and with the lengths of the first stable product of rDNA transcription, the pre-rRNA, demonstrated that the transcribed rDNA was not significantly shortened and/or condensed but rather extended in the transcriptional units. Distinct granules of about nucleosomal size which were sometimes found in apparent spacer regions as well as within matrix units of reduced fibril density were shown not to represent nucleosomes since their number per spacer unit was not inversely correlated with the length of the specific unit and also on the basis of their resistance to treatment with the detergent Sarkosyl NL-30. It is possible to structurally distinguish between transcriptionally active chromatin in which the DNA is extended in a non-nucleosomal form of chromatin and condensed, inactive chromatin within the typical nucleosomal package. The characteristic extended structure of transcriptionally active chromatin is found not only in the transcribed genes but also in non-transcribed regions within or between ("spacer") transcriptional units as well as in transcriptional units that are untranscribed amidst transcribed ones and/or have been inactivated for relatively short time. It is hypothesized that activation of transcription involves a transition from a nucleosomal to an extended chromatin organisation and that this structural transition is not specific for single "activated" genes but may involve larger chromatin regions, including adjacent untranscribed intercepts.
Thin section electron microscopy of Actinomycin D treated Tetrahymena cells and amphibian oocytes (Xenopus laevis, Triturus aZpestris) reveal no reduction in the central granules in the nuclear pore complexes. Possible reasons for the diversity between these results and earlier observations using negatively stained isolated nuclear envelopes from the same objects are discussed. The results clearly show that the presence of central granules within the nuclear pores does neither depend on nuclear RNA synthesis nor does indicate nucleocytoplasmic RNA transport. This conclusion leads to a reconsideration of the nature of the central granule. The functioning of the central granule of the nuclear pore complexes is further discussed in connection with recent studies on the ultrastructure of various types of cisternal pores.
A small fraction of HeLa cells within an exponentially growing culture showed cisternal differentiations, such as cytoplasmic as well as intranuclear annulate lamellae and special smooth surfaced endoplasmic reticulum aggregates with a typical "Cotte de maillet" appearance. Additionally, clusters of dense granules were observed in the cytoplasm which were often associated with polysomes and strongly resembled the so-called "heavy bodies" known in particular in diverse oocytes. The functional meaning of these structures is discussed. Moreover, it is deduced from the ultrastructural identity of the pore complexes in the nuclear envelope and the cytoplasmic and intranuclear annulate lamellae that the pore complex material with its highly ordered arrangement is not a structure characteristic for nucleocytoplasmically migrating material, but rather is a general structural expression of a tight binding of ribonucleoprotein (RNP) to cisternal membranes. The pore complexes are thought of as representing sites of a RNP-storage. A similar functioning is hypothesized for the "heavy body"like aggregates. To the current hypotheses on the formation of annulate lamellae and the nuclear envelope, which are based on the concept of membrane continuities and constancies, the alternative view of a self assembly mechanism of membrane constituents on nucleoprotein structures is added.
We examined the potential role of fibroblast growth factor 5 (FGF-5) as a target-derived trophic factor for spinal motoneurons. Northern analysis of total RNA from rat skeletal muscle revealed an FGF-5 mRNA transcript both during the period of embryonic motoneuron death and in the adult. Recombinant human FGF-5 supported the survival of highly enriched cultures of embryonic chick motoneurons. Significant proportions of the motoneuron survival activity of rat skeletal muscle extracts could be immunoprecipitated using an antiserum to FGF-5. The immunoprecipitable activity was present in soluble and matrix-bound forms in embryonic muscle, but bound exclusively to the extracellular matrix in adult muscle. These results, along with the secretory nature of FGF-5, suggest that FGF-5 may act as a target-derived trophic factor for motoneurons.
CILIARY neurotrophic factor (CNTF) supports the survival of embryonic motor neurons in vitro and in vivo and prevents lesion-mediated degeneration of rat motor neuron~ during early post-natal stages. Here we report that CNTF greatly reduces all the functional and morphological changes in pmnlpmn mice5, an autosomal recessive mutant leading to progressive caudo-cranial motor neuron degeneration. The first manifestations of progressive motor neuronopathy in homozygous pmnl pmn mice become apparent in the hind limbs at the end of the third post-natal week and all the mice die up to 6 or 7 weeks after birth from respiratory paralysis. Treatment with CNTF prolongs- survival- and greatly Impoves motor function of these mice. Moreover, morphological manifestations, such as loss of motor axons in the phrenic nerve and degeneration of facial motor neurons, were greatly reduced by CNTF, although the treatment did not start until the first symptoms of the disease had already become apparent and substantial degenerative changes were already present. The protective and restorative effects of CNTF in this mouse mutant give new perspectives for the treatment of human degenerative motor neuron diseases with CNTF.
Primary (giant) nuclei of the green algae Acetabularia mediterranea and A. major were studied by light and electron microscopy using in situ fixed material as well as manually isolated nuclear components. In addition, cytochemical reactions of nuclear structures and biochemical determinations of nuclear and cytoplasmic RNA and of genome DNA content were performed. The data obtained and the structures observed are interpreted as demonstralions of transcriptional activities of different gene classes. The most prominent class is the nucleolar cistrons of precursors of ribosomal RNA which occur highly repeated in clusters in the form of regularly alternating intercepts on deoxyribonucleoprotein axes of transcribed rDNA, the fibril-covered matrix units, and the fibril-free "spacer" segments. A description and a classification of the various structural complexes which seem to represent transcriptional activities is given. Quantitative evaluations of these arrangements are presented. The morphology and the dimensions of such structures are compared with the RNA molecular weight determinations and with the corresponding data reported from various animal cell systems. It is suggested that the formation of the giant nucleus is correlated with, and probably due to, an enormous amplification of transcriptionally active rDNA and packing of the extrachromosomal copies into the large nucleolar aggregate bodies.
Ciliary Neurotrophic Factor
(1994)
Electron-opaque material is shown in the perinuclear cisternae of various cell types to connect the inner and outer nuclear membrane faces. Similar bridges were observed between the outer nuclear membrane and the outer mitochondrial membrane. The intracisternal bridges of the nuclear envelope appear to be important for the structural stability of the perinuclear cisterna. Stable structural linkage of mitochondria to the outer nuclear membrane might be relevant to the understanding of the characteristic juxtanuclear accumulation of mitochondria and also provide arguments for the discussions of certain biochemical activities found in nuclear and nuclear membrane fractions.
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Ciliary neurotrophic factor (CNTF) influences the levels of choline acetyltransferase (ChAT) and tyrosine hydroxylase (TH) in cultures of dissociated sYmpathetic neurons from newborn rats. In the presence of CNTF both the total and specific activity of ChAT was increased 7 d after culture by 15- and 18-fold, respectively, as compared to cultures kept in the absence of CNTF. Between 3 and 21 d in culture in the presence of CNTF . the total ChAT activity increased by a factor of >100. Immunotitration demonstrated that the elevated ChAT levels were due to an increased number of enzyme molecules. In contrast to the increase in ChAT levels, the total and specific activity levels' of TH were decreased by 42 and 36 %, respectively, after 7 d in culture. Half-maximal effects for both ChAT increase and TH decrease were obtained at CNTF concentrations of rvO.6 ng and maximal levels were reached at I ng of CNTF per milliliter of medium. The effect of CNTF on TH and ChAT levels were seen in serum-containing medium as well as in serum-free medium. CNTF was shown to have only a small effect on the long-term s.urviVal of rat sympathetic neurons. We therefore concluded that the effects of CNTF on ChAT and TH are not due to selective survival of cells that acquire cholinergic traits in vitro, but are rather due to the induction of cholinergic differentiation of noradrenergic sympathetic neurons.
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Vorwort (Das Kind (1991) 10)
(1991)
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Vorwort (Das Kind (1992) 11)
(1992)
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Vorwort (Das Kind (1993) 14)
(1993)
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Vorwort (Das Kind (1993) 13)
(1993)
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Vorwort (Das Kind (1991) 9)
(1991)
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Vorwort (Das Kind (1994) 15)
(1994)
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Vorwort (Das Kind (1994) 16)
(1994)
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Vorwort (Das Kind (1988) 4)
(1988)
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Vorwort (Das Kind (1989) 5)
(1989)
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Vorwort (Das Kind (1989) 6)
(1989)
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Vorwort (Das Kind (1990) 8)
(1990)
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Vorwort (Das Kind (1990) 7)
(1990)
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