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101.
Jessica Gabler Jürgen Wittmann Martina Porstner Harald Renz Hans‐Martin Jäck Melanie Abram Michael Zemlin 《European journal of immunology》2013,43(11):3028-3037
Plasma cells can survive for long periods and continuously secrete protective antibodies, but plasma cell production of autoantibodies or transformation to tumor cells is detrimental. Plasma cell survival depends on exogenous factors from the surrounding microenvironment, and largely unknown intracellular mediators that regulate cell homeostasis. Here we investigated the contribution of the microRNA 24–3p (miR‐24–3p) to the survival of human plasma cells under the influence of IL‐6 and SDF‐1α (stromal cell derived factor 1), both of which are bone marrow survival niche mediators. Deep sequencing revealed a strong expression of miR‐24–3p in primary B cells, plasma blasts, plasma cells, and in plasmacytoma cells. In vitro studies using primary cells and the plasmacytoma cell line RPMI‐8226 revealed that (i) expression of miR‐24–3p mediates plasma cell survival, (ii) miR‐24–3p is upregulated by IL‐6 and SDF‐1α, (iii) IL‐6 mediates cell survival under ER stress conditions via miR‐24–3p expression, and (iv) IL‐6‐induced miR‐24–3p expression depends on the activity of the MAP kinase Erk1/2. These results suggest a direct connection between an external survival signal and an intracellular microRNA in regulating plasma cell survival. miR‐24–3p could therefore be a promising target for new therapeutic strategies for autoimmune and allergic diseases and for multiple myeloma. 相似文献
102.
Young adults more accurately remember own-age than older faces. We tested whether this own-age bias (OAB) is reduced by increased experience. Young experts (geriatric nurses) and controls performed a recognition experiment with young and old faces. Critically, while control participants demonstrated better memory for young faces, no OAB was observed in the experts. Event-related potentials revealed larger N170 and P2 amplitudes for young than old faces in both groups, suggesting no group differences during early perceptual processing. At test, N250 repetition effects were more anteriorily distributed for own- than other-age faces in control participants, whereas experts showed no corresponding effects. A larger late positive component (LPC) for old than young faces was observed in controls, but not in experts. Larger LPCs may reflect prolonged stimulus processing compromising memory retrieval. In sum, experience with other-age faces does not affect early perceptual processing, but modulates later stages related to memory retrieval. 相似文献
103.
Dirk L. Christensen Jeanette Eis Andreas W. Hansen Melanie W. Larsson David L. Mwaniki Beatrice Kilonzo 《Annals of human biology》2013,40(2):232-249
Background: Obesity is increasing rapidly in Africa, and may not be associated with the same changes in body composition among different ethnic groups in Africa.Objective: To assess abdominal visceral and subcutaneous fat thickness, prevalence of obesity, and differences in body composition in rural and urban Kenya.Subjects and methods: In a cross-sectional study carried out among Luo, Kamba and Maasai in rural and urban Kenya, abdominal visceral and subcutaneous fat thicknesses were measured by ultrasonography. Height and weight, waist, mid-upper arm circumferences, and triceps skinfold thickness were measured. Body mass index (BMI), arm fat area (AFA) and arm muscle area (AMA) were calculated.Results: Among 1430 individuals (58.3% females) aged 17–68 years, abdominal visceral and subcutaneous fat, BMI, AFA and waist circumference (WC) increased with age, and were highest in the Maasai and in the urban population. AMA was only higher with increasing age among males. The prevalence of overweight (BMI ≥ 25) (39.8% vs. 15.8%) and obesity (BMI ≥ 30) (15.5% vs. 5.1%) was highest in the urban vs. rural population.Conclusion: Abdominal visceral and subcutaneous fat thickness was higher with urban residency. A high prevalence of overweight and obesity was found. The Maasai had the highest overall fat accumulation. 相似文献
104.
Melanie Piller Inge L. Werkman Evan A. Brown Andrew J. Latimer Sarah Kucenas 《The Journal of neuroscience》2021,41(25):5353
Oligodendrocyte progenitor cells (OPCs) are specified from discrete precursor populations during gliogenesis and migrate extensively from their origins, ultimately distributing throughout the brain and spinal cord during early development. Subsequently, a subset of OPCs differentiates into mature oligodendrocytes, which myelinate axons. This process is necessary for efficient neuronal signaling and organism survival. Previous studies have identified several factors that influence OPC development, including excitatory glutamatergic synapses that form between neurons and OPCs during myelination. However, little is known about how glutamate signaling affects OPC migration before myelination. In this study, we use in vivo, time-lapse imaging in zebrafish in conjunction with genetic and pharmacological perturbation to investigate OPC migration and myelination when the GluR4A ionotropic glutamate receptor subunit is disrupted. In our studies, we observed that gria4a mutant embryos and larvae displayed abnormal OPC migration and altered dorsoventral distribution in the spinal cord. Genetic mosaic analysis confirmed that these effects were cell-autonomous, and we identified that voltage-gated calcium channels were downstream of glutamate receptor signaling in OPCs and could rescue the migration and myelination defects we observed when glutamate signaling was perturbed. These results offer new insights into the complex system of neuron-OPC interactions and reveal a cell-autonomous role for glutamatergic signaling in OPCs during neural development.SIGNIFICANCE STATEMENT The migration of oligodendrocyte progenitor cells (OPCs) is an essential process during development that leads to uniform oligodendrocyte distribution and sufficient myelination for central nervous system function. Here, we demonstrate that the AMPA receptor (AMPAR) subunit GluR4A is an important driver of OPC migration and myelination in vivo and that activated voltage-gated calcium channels are downstream of glutamate receptor signaling in mediating this migration. 相似文献
105.
106.
Liu Nian Chen Xiao Kimm Melanie A. Stechele Matthias Chen Xueli Zhang Zhimin Wildgruber Moritz Ma Xiaopeng 《Journal of molecular medicine (Berlin, Germany)》2021,99(10):1385-1398
Journal of Molecular Medicine - Inflammation is the phenotypic form of various diseases. Recent development in molecular imaging provides new insights into the diagnostic and therapeutic evaluation... 相似文献
107.
Melanie Fhrenbach Rami Abou Jamra Arndt Borkhardt Triantafyllia Brozou Petra Muschke Bernt Popp Linda K. Rey Jrg Schaper Harald Surowy Martin Zenker Christiane Zweier Dagmar Wieczorek Silke Redler 《Clinical genetics》2021,99(1):199-207
Ververi‐Brady syndrome (VBS, # 617982) is a rare developmental disorder, and loss‐of‐function variants in QRICH1 were implicated in its etiology. Furthermore, a recognizable phenotype was proposed comprising delayed speech, learning difficulties and dysmorphic signs. Here, we present four unrelated individuals with one known nonsense variant (c.1954C > T; p.[Arg652*]) and three novel de novo QRICH1 variants, respectively. These included two frameshift mutations (c.832_833del; p.(Ser278Leufs*25), c.1812_1813delTG; p.(Glu605Glyfs*25)) and interestingly one missense mutation (c.2207G > A; p.[Ser736Asn]), expanding the mutational spectrum. Enlargement of the cohort by these four individuals contributes to the delineation of the VBS phenotype and suggests expressive speech delay, moderate motor delay, learning difficulties/mild ID, mild microcephaly, short stature and notable social behavior deficits as clinical hallmarks. In addition, one patient presented with nephroblastoma. The possible involvement of QRICH1 in pediatric cancer assumes careful surveillance a key priority for outcome of these patients. Further research and enlargement of cohorts are warranted to learn about the genetic architecture and the phenotypic spectrum in more detail. 相似文献
108.
Isao Ohsawa Daisuke Honda Yusuke Suzuki Tomoo Fukuda Keisuke Kohga Eishin Morita Shinichi Moriwaki Osamu Ishikawa Yoshihiro Sasaki Masaki Tago Greg Chittick Melanie Cornpropst Sharon C. Murray Sylvia M. Dobo Eniko Nagy Sharon Van Dyke Lacy Reese Jessica M. Best Heather Iocca Phil Collis William P. Sheridan Michihiro Hide 《Allergy》2021,76(6):1789-1799
109.
Melanie Marsh Stephanie M. Lauden John D. Mahan Lydia Schneider Laura Saldivar Nina Hill Christopher Diaz Mahmoud Abdel-Rasoul Suzanne Reed 《Patient education and counseling》2021,104(5):1200-1205
ObjectiveThere are few opportunities in medical education dedicated to learning skills for effective communication in life altering patient scenarios. We therefore aimed to develop and assess a longitudinal advanced communication curriculum for pediatric residents using patient feedback and deliberate practice.MethodsPediatric residents at a large academic center were randomized into 2 groups. The intervention group received 6 educational sessions from 2019 to 2020, parent feedback of performance via the Communication Assessment Tool (CAT), and monthly communication tips. Communication skills of both groups were assessed at the end of the intervention.ResultsWe collected 937 CAT assessments on 36 first-year residents. The intervention group demonstrated statistically significant improvement in communication skills from pre to post assessment (p = 0.0063, (odds ratio (OR) 1.76, 95 % confidence interval (CI) [1.17, 2.63]) compared to the control group (p = 0.080, OR 1.41, 95 % CI [0.96, 2.05]).ConclusionsThere are patient and self-identified performance gaps in communication skills for pediatric residents, underscoring the need for formalized curricula dedicated to these skills.Practice implicationsOur study highlights the value of deliberate practice and the integration of family feedback as an educational tool in communication skills development. 相似文献
110.
Jenelle M. Slavin-Mulford Luke R. Amerson Lylli A. Cain Mark J. Hilsenroth Melanie M. Wilcox Michelle B. Stein 《Clinical psychology & psychotherapy》2021,28(6):1550-1561
This study examines the construct validity of the Social Cognition and Object Relations Scale–Global Rating Method (SCORS-G; Westen, 1995; see also Stein & Mulford, 2018) by exploring the degree of convergence across different narrative sources (i.e., early memories [EM] and psychotherapy narratives [PT]) in relation to patient- and therapist-rated psychotherapy process measures. Using a university-based outpatient sample (n = 81), we found limited convergence for SCORS-G ratings across narrative type. First, paired t tests showed that the means for six of the eight SCORS-G dimensions differed significantly between the EM and PT narratives with the majority having a large magnitude of effect. Moreover, despite 29 significant correlations between a SCORS-G dimension and either an alliance or session quality variable, only two of the eight SCORS-G dimensions significantly correlated with the same process variable across narrative type (e.g., patient-rated session depth with SCORS-G Self Esteem [SE] and Identity and Coherence of Self [ICS]). Importantly, the high degree of theoretical coherence in the associations that emerged between the SCORS-G dimensions and the process variables suggest that the lack of convergence was not due to limited validity of the SCORS-G. Instead, the results underscore the importance of multi-method assessment techniques by highlighting that the manner in which a narrative is elicited will impact the object relational content patients provide. Future research and clinical implications related to the SCORS-G, alliance and psychotherapy process are discussed. 相似文献