217 research outputs found

    Endogenous leukemia inhibitory factor protects photoreceptor cells against light-induced degeneration

    Get PDF
    PURPOSE: Expression of leukemia inhibitory factor (LIF) by a subset of MĂŒller glia cells has recently been implicated in an endogenous survival response to photoreceptor injury in a model of inherited retinal degeneration. To investigate whether such a LIF-controlled survival pathway might be commonly induced upon photoreceptor injury independently of the nature of the toxic stimulus, we analyzed the role of LIF during light-induced retinal degeneration. METHODS: Lif(+/-) and Lif(-/-) mice were exposed to 15,000 lx of white light for 2 h. Retinal morphology and rhodopsin content were analyzed nine days after light exposure. Gene expression studies were done using real-time PCR. Protein levels were determined by western blotting using specific antibodies. RESULTS: A lack of LIF reduced survival of photoreceptor cells after light exposure. In the absence of LIF several genes encoding molecules involved in the Janus kinase/signal transducer and activator of transcription (Jak/STAT) signaling pathway were not activated after light exposure. Presence or absence of LIF did not affect AKT (also known as protein kinase B, PKB) signaling and had only a mild effect on extracellular regulated kinase (ERK) phosphorylation. Stress-induced glial fibrillary acidic protein (GFAP) induction was minimal in the absence of LIF. CONCLUSIONS: Our results suggest that increased retinal expression of LIF is a general response to photoreceptor injury. Independent of the nature of the toxic insult (gene mutation, light), LIF may activate an endogenous rescue pathway that protects viable photoreceptor cells, leading to an increased photoreceptor survival in the stressed retina. This defense system may depend on the Jak/STAT pathway and may involve endothelin 2 (EDN2) but not (or only minimally) AKT and ERK1,2 signaling

    Levels of Structural Integration Mediate the Impact of Metacognition on Functioning in Non-affective Psychosis: Adding a Psychodynamic Perspective to the Metacognitive Approach

    Get PDF
    Synthetic metacognition is defined by integrative and contextualizing processes of discrete reflexive moments. These processes are supposed to be needed to meet intrapsychic as well as interpersonal challenges and to meaningfully include psychotic experience in a personal life narrative. A substantial body of evidence has linked this phenomenon to psychosocial functioning and treatment options were developed. The concept of synthetic metacognition, measured with the Metacognition Assessment Scale-Abbreviated (MAS-A), rises hope to bridge gaps between therapeutic orientations and shares valuable parallels to modern psychodynamic constructs, especially the 'levels of structural integration' of the Operationalized Psychodynamic Diagnosis (OPD-2). As theoretical distinctions remain, aim of this study was to compare the predictive value of both constructs with regard to psychosocial functioning of patients with non-affective psychoses, measured with the International Classification of Functioning, Disability and Health (MINI-ICF-APP). It was further explored if levels of structural integration (OPD-LSIA) would mediate the impact of metacognition (MAS-A) on function (MINI-ICF-APP). Expert ratings of synthetic metacognition (MAS-A), the OPD-2 'levels of structural integration' axis (OPD-LSIA), psychosocial functioning (MINI-ICF-APP) and assessments of general cognition and symptoms were applied to 100 individuals with non-affective psychoses. Whereas both, MAS-A and OPD-LSIA, significantly predicted MINI-ICF-APP beyond cognition and symptoms, OPD-LSIA explained a higher share of variance and mediated the impact of MAS-A on MINI-ICF-APP. Levels of structural integration, including the quality of internalized object representations and unconscious interpersonal schemas, might therefore be considered as valuable predictors of social functioning and as one therapeutic focus in patients with non-affective psychoses. Structural integration might go beyond and form the base of a person's actual reflexive and metacognitive capabilities. Psychotherapeutic procedures specific for psychoses may promote and challenge a patient's metacognitive capacities, but should equally take the need for maturing structural skills into account. Modern psychodynamic approaches to psychosis are shortly presented, providing concepts and techniques for the implicit regulation of interpersonal experience and aiming at structural integration in this patient group

    High-intensity interval training for overweight adolescents: program acceptance of a media supported intervention and changes in body composition

    Get PDF
    High-intensity interval training (HIIT) consists of short intervals of exercise at high intensity intermitted by intervals of lower intensity and is associated with improvement of body composition and metabolic health in adults. Studies in overweight adolescents are scarce. We conducted a randomized controlled trial in overweight adolescents to compare acceptance and attendance of HIIT with or without weekly motivational encouragement through text messages and access to a study website. HIIT was offered for six months (including summer vacation) twice a week (60 min/session). Participation rates were continuously assessed and acceptance was measured. Clinical parameters were assessed at baseline and after six months. Twenty-eight adolescents participated in this study (age 15.5 +/- 1.4; 54% female). The standard deviation score for body mass index over all participants was 2.33 at baseline and decreased by 0.026 (95% CI - 0.048 to 0.10) units, p = 0.49. Waist to height ratio was 0.596 at baseline and decreased by 0.013 (95% CI 0.0025 to 0.024), p = 0.023. Participation within the first two months ranged from 65% to 75%, but fell to 15% within the last three months. Attendance in the intervention group was 14% (95% CI - 8 to 37), p = 0.18, higher than the control group. Overall program content was rated as \"good\" by participants, although high drop-out rates were observed. Summer months constitute a serious problem regarding attendance. The use of media support has to be assessed further in appropriately powered trials

    Das ILZNAWI-Modell: Inklusive LernzugÀnge im naturwissenschaftlichen Unterricht. Zur Planbarkeit von Individualisierung und Kooperation am Gemeinsamen Gegenstand

    Get PDF
    Der Beitrag stellt das im Rahmen des Projekts „Reckahner Modelle zur inklusiven Unterrichtsplanung“ (REMI) entwickelte ILZNAWI-Modell („Inklusive LernzugĂ€nge im naturwissenschaftlichen Unterricht“) vor. Es dient dazu, den Gemeinsamen Gegenstand im naturwissenschaftlichen Unterricht inklusionsförderlich und heterogenitĂ€tssensibel auszudifferenzieren und bildet auf Grundlage eines weiten InklusionsverstĂ€ndnisses gestufte LernzugĂ€nge und Abstraktionsgrade ab. Der Artikel gibt einen Überblick ĂŒber diesbezĂŒglich bestehende Forschungsprojekte und Unterrichtskonzepte, leitet hieraus die Notwendigkeit fĂŒr das Modell ab und anschließend dessen Entwicklung theoretisch her. Anhand ausgewĂ€hlter Stufenmodelle fĂŒr die FĂ€cher Biologie, Physik und Chemie wird die Planungsanwendung konkretisiert. In einer Unterrichtssequenz zur Evolution des Menschen werden Möglichkeiten zur Verbindung von Individualisierung und Kooperation aufgezeigt. Weitere Umsetzungsideen der FĂ€cher Chemie und Physik verdeutlichen die Bandbreite an Nutzungsmöglichkeiten des Modells. (DIPF/Orig.

    Stat5 determines the development of mammary alveolar cells

    Get PDF
    Functional development of mammary epithelium during pregnancy depends on prolactin signaling. However, the underlying molecular and cellular events are not fully understood. We examined the specific contributions of the prolactin receptor (PrlR) and the signal transducers and activators of transcription 5a and 5b (referred to as Stat5) in the formation and differentiation of mammary alveolar epithelium. PrlR- and Stat5-null mammary epithelia were transplanted into wild-type hosts, and pregnancy-mediated development was investigated at a histological and molecular level. Stat5-null mammary epithelium developed ducts but failed to form alveoli, and no milk protein gene expression was observed. In contrast, PrlR-null epithelium formed alveoli-like structures with small open lumina. Electron microscopy revealed undifferentiated features of organelles and a perturbation of cell–cell contacts in PrlR- and Stat5-null epithelia. Expression of NKCC1, an Na-K-Cl cotransporter characteristic for ductal epithelia, and ZO-1, a protein associated with tight junction, were maintained in the alveoli-like structures of PrlR- and Stat5-null epithelia. In contrast, the Na-Pi cotransporter Npt2b, and the gap junction component connexin 32, usually expressed in secretory epithelia, were undetectable in PrlR- and Stat5- null mice. These data demonstrate that signaling via the PrlR and Stat5 is critical for the proliferation and differentiation of mammary alveoli during pregnancy

    Smash the Paywalls: Workflows und Werkzeuge fĂŒr den grĂŒnen Weg des Open Access

    Get PDF
    Der Beitrag diskutiert Bedeutung, praktisches Potenzial und konkrete Herausforderungen von bibliothekarischen Serviceangeboten fĂŒr den grĂŒnen Weg des Open Access. Er adressiert Einrichtungen, die einen Zweitveröffentlichungsservice auf- bzw. ausbauen wollen und prĂ€sentiert mögliche Workflows und Werkzeuge. Im Fokus stehen Möglichkeiten der Gewinnung von Autor*innen und der Akquise von Publikationsdaten, rechtliche Grundlagen fĂŒr Zweitveröffentlichungen sowie die einzelnen Schritte hin zu einer Zweitveröffentlichung. Zudem werden Hinweise fĂŒr die Automatisierung von einzelnen Prozessen gegeben. Dem Beitrag angehĂ€ngt sind vier Checklisten, die im Alltag herangezogen werden können

    Signal transducer and activator of transcription (Stat) 5 controls the proliferation and differentiation of mammary alveolar epithelium

    Get PDF
    Functional development of mammary epithelium during pregnancy depends on prolactin signaling. However, the underlying molecular and cellular events are not fully understood. We examined the specific contributions of the prolactin receptor (PrlR) and the signal transducers and activators of transcription 5a and 5b (referred to as Stat5) in the formation and differentiation of mammary alveolar epithelium. PrlR- and Stat5-null mammary epithelia were transplanted into wild-type hosts, and pregnancy-mediated development was investigated at a histological and molecular level. Stat5-null mammary epithelium developed ducts but failed to form alveoli, and no milk protein gene expression was observed. In contrast, PrlR-null epithelium formed alveoli-like structures with small open lumina. Electron microscopy revealed undifferentiated features of organelles and a perturbation of cell–cell contacts in PrlR- and Stat5-null epithelia. Expression of NKCC1, an Na-K-Cl cotransporter characteristic for ductal epithelia, and ZO-1, a protein associated with tight junction, were maintained in the alveoli-like structures of PrlR- and Stat5-null epithelia. In contrast, the Na-Pi cotransporter Npt2b, and the gap junction component connexin 32, usually expressed in secretory epithelia, were undetectable in PrlR- and Stat5-null mice. These data demonstrate that signaling via the PrlR and Stat5 is critical for the proliferation and differentiation of mammary alveoli during pregnancy
    • 

    corecore