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61.
Ulrich Gergs Peter Boknik Igor B. BuchwalowLarissa Fabritz Nicole Gründker Dana KucerovaMarek Matus Franziska WernerWilhelm Schmitz Joachim Neumann 《International journal of cardiology》2012,154(2):116-121
Background
Protein phosphatase 5 (PP5) a serine/threonine phosphatase is ubiquitously expressed in mammalian tissues including the heart, but its physiological role in the heart is still unknown. Therefore, we used a transgenic mouse model to get a first insight into the cardiac role of PP5.Methods and results
We generated transgenic mice with cardiac myocyte specific overexpression of PP5. Successful overexpression of PP5 was demonstrated by Western blotting, immunohistochemistry and enhanced arachidonic acid-stimulated protein phosphatase activity in transgenic hearts. Cardiac function was examined on the level of isolated cardiac myocytes, isolated organs and in intact animals. Whereas Ca2+ transients and cell shortening remained unchanged, L-type Ca2+ currents were decreased in isolated cardiac myocytes from transgenic mice. Ventricular contractility was reduced in isolated perfused hearts under basal conditions and after β-adrenergic stimulation. In intact animals, echocardiography revealed increased left ventricular diameters and decreased contractility and invasively measured hemodynamic performance by left ventricular catheterization demonstrated a reduced response to β-adrenergic stimulation in transgenic mice compared to wild type.Conclusions
Overexpression of PP5 affected contractility and β-adrenergic signaling in the hearts of transgenic mice. Taken together, these findings are indicative of a regulatory role of PP5 in cardiac function. 相似文献62.
Jain P Javdan M Feger FK Chiu PY Sison C Damle RN Bhuiya TA Sen F Abruzzo LV Burger JA Rosenwald A Allen SL Kolitz JE Rai KR Chiorazzi N Sherry B 《Haematologica》2012,97(4):599-607
Background
The levels and clinical relevance of Th17 cells and other interleukin-17-producing cells have not been analyzed in chronic lymphocytic leukemia. The objective of this study was to quantify blood and tissue levels of Th17 and other interleukin-17-producing cells in patients with this disease and correlate blood levels with clinical outcome.Design and Methods
Intracellular interleukin-17A was assessed in blood and splenic mononuclear cells from patients with chronic lymphocytic leukemia and healthy subjects using flow cytometry. Interleukin-17A-producing cells were analyzed in formalin-fixed, paraffin-embedded spleen and lymph node sections using immunohistochemistry and immunofluorescence.Results
The absolute numbers of Th17 cells in peripheral blood mononuclear cells and the percentages of Th17 cells in spleen cell suspensions were higher in patients with chronic lymphocytic leukemia than in healthy subjects; in six out of eight paired chronic lymphocytic leukemia blood and spleen sample comparisons, Th17 cells were enriched in spleen suspensions. Circulating Th17 levels correlated with better prognostic markers and longer overall survival of the patients. Two “non-Th17” interleukin-17-expressing cells were identified in chronic lymphocytic leukemia spleens: proliferating cells of the granulocytic lineage and mature mast cells. Granulocytes and mast cells in normal spleens did not express interleukin-17. Conversely, both chronic lymphocytic leukemia and healthy lymph nodes contained similar numbers of interleukin-17+ mast cells as well as Th17 cells.Conclusions
Th17 cells are elevated in chronic lymphocytic leukemia patients with better prognostic markers and correlate with longer survival. Furthermore, non-Th17 interleukin-17A-expressing cells exist in chronic lymphocytic leukemia spleens as maturing granulocytes and mature mast cells, suggesting that the microenvironmental milieu in leukemic spleens promotes the recruitment and/or expansion of Th17 and other IL-17-expressing cells. The pathophysiology of Th17 and non-Th17-interleukin-producing cells in chronic lymphocytic leukemia and their distributions and roles in this disease merit further study. 相似文献63.
Udo Dannlowski Harald Kugel Franziska Huber Anja Stuhrmann Ronny Redlich Dominik Grotegerd Katharina Dohm Christina Sehlmeyer Carsten Konrad Bernhard T. Baune Volker Arolt Walter Heindel Pienie Zwitserlood Thomas Suslow 《Human brain mapping》2013,34(11):2899-2909
Major depression has been repeatedly associated with amygdala hyper‐responsiveness to negative (but not positive) facial expressions at early, automatic stages of emotion processing using subliminally presented stimuli. However, it is not clear whether this “limbic bias” is a correlate of depression or represents a vulnerability marker preceding the onset of the disease. Because childhood maltreatment is a potent risk factor for the development of major depression in later life, we explored whether childhood maltreatment is associated with amygdalar emotion processing bias in maltreated but healthy subjects. Amygdala responsiveness to subliminally presented sad and happy faces was measured by means of fMRI at 3 T in N = 150 healthy subjects carefully screened for psychiatric disorders. Childhood maltreatment was assessed by the 25‐item childhood trauma questionnaire (CTQ). A strong association of CTQ‐scores with amygdala responsiveness to sad, but not happy facial expressions emerged. This result was further qualified by an interaction of emotional valence and CTQ‐scores and was not confounded by trait anxiety, current depression level, age, gender, intelligence, education level, and more recent stressful life‐events. Childhood maltreatment is apparently associated with detectable changes in amygdala function during early stages of emotion processing which resemble findings described in major depression. Limbic hyper‐responsiveness to negative facial cues could be a consequence of the experience of maltreatment during childhood increasing the risk of depression in later life. Limitation: the present association of limbic bias and maltreatment was demonstrated in the absence of psychopathological abnormalities, thereby limiting strong conclusions. Hum Brain Mapp 34:2899–2909, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
64.
65.
Franziska Schreiber Regina Steil 《Journal of behavior therapy and experimental psychiatry》2013,44(2):158-164
Background and objectivesNegative distorted self-images (NSI) allegedly maintain social anxiety in adults suffering from social anxiety disorder (SAD). These NSI are activated in feared social situations and are often linked to past socially traumatic events. However, because empirical evidence on the presence and characteristics of such NSI in adolescents suffering from SAD is limited, the aim of the present study is to examine the nature of NSI in adolescent SAD patients.MethodsUsing a semi-structured interview, 31 adolescents with a primary diagnosis of SAD and 31 healthy adolescents (HA) who were matched for age and gender, completed a questionnaire set assessing the characteristics of NSI, social anxiety and depression.ResultsRelative to the HA-group, those suffering from SAD reported experiencing NSI significantly more frequently, more vividly, and with greater distress. No significant differences between the groups emerged regarding a link between the NSI and an autobiographical event. However, NSI were reported as more often having an observer-perspective in the SAD as compared to the HA-group. Hierarchical regression analysis revealed that certain characteristics of the NSI predict social anxiety beyond the influence of depression in adolescents with SAD.DiscussionNSI seem to be an important feature of adolescent SAD and phenomenological comparable to NSI in adults suffering from SAD.ConclusionsSpecific interventions aiming to correct NSI, which have proven to be highly effective in adults, should be developmentally-adapted and evaluated in future studies. 相似文献
66.
Seegers J Vos MA Flevari P Willems R Sohns C Vollmann D Lüthje L Kremastinos DT Floré V Meine M Tuinenburg A Myles RC Simon D Brockm?ller J Friede T Hasenfu? G Lehnart SE Zabel M;EUTrigTreat Clinical Study Investigators 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2012,14(3):416-422
67.
68.
Kari Bø Gunvor Hilde Jette Stær Jensen Franziska Siafarikas Marie Ellstrøm Engh 《International urogynecology journal》2013,24(12):2065-2070
Introduction and hypothesis
Theoretically, tight or strong pelvic floor muscles may impair the progress of labor and lead to instrumental deliveries. We aimed to investigate whether vaginal resting pressure, pelvic floor muscle strength, or endurance at midpregnancy affect delivery outcome.Methods
This was a prospective cohort study of women giving birth at a university hospital. Vaginal resting pressure, pelvic floor muscle strength, and endurance in 300 nulliparous pregnant women were assessed at mean gestational week 20.8 (±1.4) using a high precision pressure transducer connected to a vaginal balloon. Delivery outcome measures [acute cesarean section, prolonged second stage of labor (> 2 h), instrumental vaginal delivery (vacuum and forceps), episiotomy, and third- and fourth-degree perineal tear) were retrieved from the hospital’s electronic birth records.Results
Twenty-three women were lost to follow-up, mostly because they gave birth at another hospital. Women with prolonged second stage had significantly higher resting pressure than women with second stage less than 2 h; the mean difference was 4.4 cmH2O [95 % confidence interval (CI) 1.2–7.6], p?<?0.01, adjusted odds ratio 1.049 (95 % CI 1.011–1.089, p?=?0.012). Vaginal resting pressure did not affect other delivery outcomes. Pelvic floor muscle strength and endurance similarly were not associated with any delivery outcomes.Conclusions
While midpregnancy vaginal resting pressure is associated with prolonged second stage of labor, neither vaginal resting pressure nor pelvic floor muscle strength or endurance are associated with operative delivery or perineal tears. Strong pelvic floor muscles are not disadvantageous for vaginal delivery. 相似文献69.
Franziska Rausch Sarah EiflerAndrea Esser Christine EsslingerFrederike Schirmbeck Andreas Meyer-LindenbergMathias Zink 《Comprehensive psychiatry》2013
The identification of patients carrying an increased risk of psychosis is one of the most important demands in schizophrenia research. Currently used diagnostic instruments mainly focus on either attenuated psychotic symptoms and brief limited intermittent psychotic symptoms or solely cognitive basic symptoms. The “Early Recognition Inventory based on IRAOS” (ERIraos) has been developed as a comprehensive assessment of both symptom groups within one scale. We compared the results obtained by ERIraos with an international standard instrument, the “Comprehensive Assessment of At Risk Mental States” (CAARMS) and applied both scales in a sample of 121 outpatients positively tested on a screening checklist for at risk mental states (ARMS). Subsamples were classified as first episode of psychosis, late ARMS with prevalent attenuated psychotic symptoms and/or brief limited intermittent psychotic symptoms, earlier stages of ARMS presenting cognitive basic symptoms as well as a vulnerability group, also differing regarding mean age and psychosocial functioning. Our results point to a higher sensitivity of ERIraos compared to scales that mainly focus on attenuated psychotic symptoms and brief limited intermittent psychotic symptoms. A detailed assessment of cognitive basic symptoms seems to be important in early detection, might be an important focus for therapeutic interventions in ARMS patients and might sustain attempts to alleviate cognitive dysfunction in schizophrenia. 相似文献
70.