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1.
J Affect Disord ; 339: 237-255, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37437729

RESUMO

BACKGROUND: Depression is one of the most common mental disorders and a leading cause of disability worldwide. In adults, depression is characterized by decreased vagal activity (vagally-mediated heart rate variability; vmHRV), while vmHRV is inversely correlated with depressive symptoms. In children/adolescents, a 2016 synthesis (4 studies, 259 individuals) found similarly decreased vmHRV in clinical depression, but no significant association between depressive symptoms and vmHRV (6 studies, 2625 individuals). Given the small number of studies previously considered for synthesis and the rapidly growing evidence base in this area, a meta-analytic update was warranted. METHOD: A previous review was updated by a systematic literature search to identify studies that (a) compared vmHRV in clinically depressed children/adolescents with non-depressed controls and (b) reported associations between vmHRV and depression severity. RESULTS: The search update identified 5 additional studies for group comparison (k = 9 studies in total, n = 608 individuals in total) and 15 additional studies for correlational meta-analysis (k = 21 studies in total, n = 4224 individuals in total). Evidence was found for lower resting-state vmHRV in clinically depressed children/adolescents compared to healthy controls (SMD = -0.593, 95 % CI [-1.1760; -0.0101], I2 = 90.92 %) but not for a significant association between vmHRV and depressive symptoms (r = -0.053, 95 % CI [-0.118; 0.012], I2 = 65.77 %). Meta-regression revealed a significant association between depressive symptoms and vmHRV as a function of sex. LIMITATIONS: The samples considered are highly heterogeneous. Data on the longitudinal association between vmHRV and depression are currently lacking. CONCLUSION: The present findings support the use of vmHRV as a biomarker for clinical depression in children/adolescents.

2.
J Bone Miner Res ; 37(9): 1761-1774, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35689447

RESUMO

The formation of the bone marrow cavity is a prerequisite for endochondral ossification. In reviews and textbooks, it is occasionally reported that osteoclasts are essential for bone marrow cavity formation removing hypertrophic chondrocytes. Mice lacking osteoclasts or having functionally defective osteoclasts have osteopetrotic bones, yet they still form a bone marrow cavity. Here, we investigated the role of osteoclasts and macrophages in bone marrow cavity formation during embryogenesis. Macrophages can assist osteoclasts in matrix removal by phagocytosing resorption byproducts. Rank-deficient mice, lacking osteoclasts, and Pu.1-deficient mice, lacking monocytes, macrophages, and osteoclasts, displayed a delay in bone marrow cavity formation and a lengthening of the zone of hypertrophic chondrocytes. F4/80-positive monocyte/macrophage numbers increased by about fourfold in the bone marrow cavity of E18.5 Rank-deficient mice. Based on lineage-tracing experiments, the majority of the excess F4/80 cells were derived from definitive hematopoietic precursors of the fetal liver. In long bones of both Rank-/- and Pu.1-/- specimens, Mmp9-positive cells were still present. In addition to monocytes, macrophages, and osteoclasts, Ctsb-positive septoclasts were lost in Pu.1-/- specimens. The mineralization pattern was altered in Rank-/- and Pu.1-/- specimens, revealing a significant rise in transverse-oriented mineralized structures. Taken together, our findings imply that early on during bone marrow cavity formation, osteoclasts facilitate the entry of blood vessels and later the turnover of hypertrophic chondrocytes, whereas macrophages appear to play no major role. Furthermore, the absence of septoclasts in Pu.1-/- specimens suggests that septoclasts are either derived from Pu.1-dependent precursors or require PU.1 activity for their differentiation. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Medula Óssea , Osteoclastos , Animais , Células da Medula Óssea , Osso e Ossos , Diferenciação Celular , Desenvolvimento Embrionário , Macrófagos , Camundongos
3.
J Bone Miner Res ; 37(7): 1335-1351, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35560108

RESUMO

Osteoarthritis (OA) is a common degenerative disease of the joint, with a complex multifactorial not yet fully understood etiology. Over the past years, the Wnt signaling pathway has been implicated in osteoarthritis. In a recent genomewide association study (GWAS), the chromosomal location on chromosome 1, linked to the Wnt3a-Wnt9a gene locus, was identified as the most significant locus associated with a thumb osteoarthritis endophenotype. Previously, it was shown that WNT9a is involved in maintaining synovial cell identity in the elbow joint during embryogenesis. Here, we report that the conditional loss of Wnt9a in the Prx1-Cre expressing limb mesenchyme or Prg4-CreER expressing cells predispositions the mice to develop spontaneous OA-like changes with age. In addition, the trabecular bone volume is altered in these mice. Similarly, mice with a conditional loss of Wnt4 in the limb mesenchyme are also more prone to develop spontaneously OA-like joint alterations with age. These mice display additional alterations in their cortical bone. The combined loss of Wnt9a and Wnt4 increased the likelihood of the mice developing osteoarthritis-like changes and enhanced disease severity in the affected mice. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Osteoartrite , Proteínas Wnt , Proteína Wnt4 , Animais , Osso e Ossos/metabolismo , Osso Cortical/metabolismo , Mesoderma/metabolismo , Camundongos , Osteoartrite/genética , Proteínas Wnt/genética , Via de Sinalização Wnt/genética , Proteína Wnt4/genética
4.
Pneumologie ; 76(5): 340-344, 2022 May.
Artigo em Alemão | MEDLINE | ID: mdl-34704238

RESUMO

BACKGROUND: To reduce the exposure of young people to smoking scenes in films, the World Health Organization has recommended classifying films with smoking scenes as unsuitable for children and adolescents. AIM: To examine the question whether this recommendation is being implemented in Germany and the USA by comparing the ratings for films with and without smoking scenes in both countries. METHOD: The selection criterion for the films was the box office result in German theaters in 2019. The 50 most successful US productions and the 50 most successful productions from Germany were content analyzed. The questions raised were: (1) how high the proportion of smoke-free films was in these two film samples, and (2) how high the proportion of films with smoking scenes was that were classified as unsuitable for young people. All films with an age rating below 16 years were considered suitable for children and adolescents. RESULTS: A total of 52 of the 100 films were smokefree. The rate was 64 % for US productions, compared to 40 % for German productions (p = 0.016). According to the German Self-regulatory Organization for the Cinema (FSK) rating system, 87 % of the films were suitable for young people. Overall, the proportion of smokefree films was higher for films suitable for young people than for films not suitable for young people (56 % vs. 23 %; p = 0.025). Of the 48 films with smoking, the FSK classified 79 % as suitable for minors. With regard to the age ratings for films with smoking scenes, there was no difference between the MPAA and FSK ratings for the top 50 US productions. CONCLUSIONS: Neither the USA nor Germany has implemented the recommendation of the World Health Organization to protect young people from smoking scenes in films in a satisfactory manner. In Germany, films with smoking scenes are largely classified as suitable for minors.


Assuntos
Menores de Idade , Filmes Cinematográficos , Adolescente , Criança , Alemanha , Humanos , Fumar/epidemiologia , Organização Mundial da Saúde
5.
J Bone Miner Res ; 36(10): 2039-2052, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34155688

RESUMO

In hypertrophic chondrocytes, ß-catenin has two roles. First, it locally suppresses the differentiation of osteoclasts at the chondro-osseous junction by maintaining the pro-osteoclastic factor receptor activator of NF-κB ligand (RANKL) at low levels. Second, it promotes the differentiation of osteoblast-precursors from chondrocytes. Yet, ß-catenin is a dual-function protein, which can either participate in cell-cell adherens junctions or serve as a transcriptional co-activator in canonical Wnt signaling interacting with T-cell factor/lymphoid enhancer-binding factor (TCF/LEF) transcription factors. Hence, whenever studying tissue-specific requirements of ß-catenin using a conventional conditional knockout approach, the functional mechanisms underlying the defects in the conditional mutants remain ambiguous. To decipher mechanistically which of the two molecular functions of ß-catenin is required in hypertrophic chondrocytes, we used different approaches. We analyzed the long bones of newborn mice carrying either the null-alleles of Lef1 or Tcf7, or mice in which Tcf7l2 was conditionally deleted in the hypertrophic chondrocytes, as well as double mutants for Lef1 and Tcf7l2, and Tcf7 and Tcf7l2. Furthermore, we analyzed Ctnnb1 mutant newborns expressing a signaling-defective allele that retains the cell adhesion function in hypertrophic chondrocytes. None of the analyzed Tcf/Lef single or double mutants recapitulated the previously published phenotype upon loss of ß-catenin in hypertrophic chondrocytes. However, using this particular Ctnnb1 allele, maintaining cell adhesion function, we show that it is the co-transcriptional activity of ß-catenin, which is required in hypertrophic chondrocytes to suppress osteoclastogenesis and to promote chondrocyte-derived osteoblast differentiation. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Condrócitos , beta Catenina , Animais , Diferenciação Celular , Condrócitos/metabolismo , Camundongos , Osteoclastos/metabolismo , Fatores de Transcrição TCF , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
6.
Cell Death Dis ; 12(5): 494, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33990546

RESUMO

Agonists and antagonists of the canonical Wnt signaling pathway are modulators of pathological aspects of rheumatoid arthritis (RA). Their activity is primarily modifying bone loss and bone formation, as shown in animal models of RA. More recently, modulation of Wnt signaling by the antagonist Sclerostin has also been shown to influence soft-tissue-associated inflammatory aspects of the disease pointing towards a role of Wnt signaling in soft-tissue inflammation as well. Yet, nothing is known experimentally about the role of Wnt ligands in RA. Here we provide evidence that altering Wnt signaling at the level of a ligand affects all aspects of the rheumatoid arthritic disease. WNT9a levels are increased in the pannus tissue of RA patients, and stimulation of synovial fibroblasts (SFB) with tumor necrosis factor (TNF) leads to increased transcription of Wnt9a. Loss of Wnt9a in a chronic TNF-dependent RA mouse model results in an aggravation of disease progression with enhanced pannus formation and joint destruction. Yet, loss of its activity in the acute K/BxN serum-transfer induced arthritis (STIA) mouse model, which is independent of TNF signaling, has no effect on disease severity or progression. Thus, suggesting a specific role for WNT9a in TNF-triggered RA. In synovial fibroblasts, WNT9a can activate the canonical Wnt/ß-catenin pathway, but it can also activate P38- and downregulate NFκB signaling. Based on in vitro data, we propose that loss of Wnt9a creates a slight proinflammatory and procatabolic environment that boosts the TNF-mediated inflammatory response.


Assuntos
Artrite Reumatoide/metabolismo , Proteínas Wnt/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Transgênicos
7.
Cell Res ; 30(10): 885-901, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32686768

RESUMO

Osteosarcoma (OS) is the most frequent primary malignant bone tumor in urgent need of better therapies. Using genetically modified mouse models (GEMMs), we demonstrate that Wnt signaling promotes c-Fos-induced OS formation via the actions of the collagen-modifying enzyme Loxl2. c-Fos/AP-1 directly regulates the expression of the Wnt ligands Wnt7b and Wnt9a in OS cells through promoter binding, and Wnt7b and Wnt9a in turn promote Loxl2 expression in murine and human OS cells through the transcription factors Zeb1 and Zeb2. Concordantly, inhibition of Wnt ligand secretion by inactivating the Wnt-less (Wls) gene in osteoblasts in c-Fos GEMMs either early or in a therapeutic setting reduces Loxl2 expression and progression of OS. Wls-deficient osteosarcomas proliferate less, are less mineralized and are enriched in fibroblastic cells surrounded by collagen fibers. Importantly, Loxl2 inhibition using either the pan-Lox inhibitor BAPN or a specific inducible shRNA reduces OS cell proliferation in vitro and decreases tumor growth and lung colonization in murine and human orthotopic OS transplantation models. Finally, OS development is delayed in c-Fos GEMMs treated with BAPN or with specific Loxl2 blocking antibodies. Congruently, a strong correlation between c-FOS, LOXL2 and WNT7B/WNT9A expression is observed in human OS samples, and c-FOS/LOXL2 co-expression correlates with OS aggressiveness and decreased patient survival. Therefore, therapeutic targeting of Wnt and/or Loxl2 should be considered to potentiate the inadequate current treatments for pediatric, recurrent, and metastatic OS.


Assuntos
Aminoácido Oxirredutases/metabolismo , Regulação Neoplásica da Expressão Gênica , Osteossarcoma/metabolismo , Via de Sinalização Wnt , Animais , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos C57BL
8.
Curr Osteoporos Rep ; 17(3): 129-137, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30949840

RESUMO

PURPOSE OF REVIEW: The goal of the review is to summarize the current knowledge on the process of chondrocyte-to-osteoblast transdifferentiation during endochondral bone formation and its potential implications in fracture healing and disease. RECENT FINDINGS: Lineage tracing experiments confirmed the transdifferentiation of chondrocytes into osteoblasts. More recent studies lead to the discovery of molecules involved in this process, as well as to the hypothesis that these cells may re-enter a stem cell-like phase prior to their osteoblastic differentiation. This review recapitulates the current knowledge regarding chondrocyte transdifferentiating into osteoblasts, the developmental and postnatal events where transdifferentiation appears to be relevant, and the molecules implicated in this process.


Assuntos
Condrócitos/citologia , Consolidação da Fratura/fisiologia , Osteoblastos/citologia , Osteogênese/fisiologia , Diferenciação Celular , Humanos
9.
Genes Cells ; 24(4): 307-317, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30801848

RESUMO

Mutations in the human receptor tyrosine kinase ROR2 are associated with Robinow syndrome (RRS) and brachydactyly type B1. Amongst others, the shortened limb phenotype associated with RRS is recapitulated in Ror2-/- mutant mice. In contrast, Ror1-/- mutant mice are viable and show no limb phenotype. Ror1-/- ;Ror2-/- double mutants are embryonic lethal, whereas double mutants containing a hypomorphic Ror1 allele (Ror1hyp ) survive up to birth and display a more severe shortened limb phenotype. Both orphan receptors have been shown to act as possible Wnt coreceptors and to mediate the Wnt5a signal. Here, we analyzed genetic interactions between the Wnt ligand, Wnt9a, and Ror2 or Ror1, as Wnt9a has also been implicated in skeletal development. Wnt9a-/- single mutants display a mild shortening of the long bones, whereas these are severely shortened in Ror2-/- mutants. Ror2-/- ;Wnt9a-/- double mutants displayed even more severely shortened long bones, and intermediate phenotypes were observed in compound Ror2;Wnt9a mutants. Long bones were also shorter in Ror1hyp/hyp ;Wnt9a-/- double mutants. In addition, Ror1hyp/hyp ;Wnt9a-/- double mutants displayed a secondary palate cleft phenotype, which was not present in the respective single mutants. Interestingly, 50% of compound mutant pups heterozygous for Ror2 and homozygous mutant for Ror1 also developed a secondary palate cleft phenotype.


Assuntos
Fissura Palatina/genética , Epistasia Genética , Deformidades Congênitas dos Membros/genética , Mutação , Osteogênese/genética , Proteínas Wnt/genética , Animais , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase
10.
Genet Med ; 20(1): 76-82, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28640237

RESUMO

PurposeTo facilitate ethically acceptable and practically successful health care-embedded biobanking, the attitudes and understanding of patients and their motivation to participate need to be explored.MethodsA questionnaire study was conducted among 760 outpatients of a northern German university hospital to assess their awareness of, and motivation for giving broad consent to health care-embedded biobanking, also addressing the issue of feedback on individual-level research findings.ResultsThe overall willingness to give broad consent was high (86.9%) in our study, even though the subjective and objective understanding of patients was found to be only modest. Most participants who consented did so for prosocial reasons (altruism, solidarity, reciprocity, gratitude), whereas self-interest or worries about disadvantages played only a marginal role. Better objective understanding was associated with both a greater demand for feedback on individual research findings and a higher willingness to consent. Intermittent modification of the information material provided by the hospital led to significantly improved objective understanding.ConclusionPatient willingness to give broad consent to health care-embedded biobanking is high, with prosocial reasons driving decision making more than factual knowledge and approval or disapproval of specific consent elements. Future efforts to improve the information material used in health care-embedded biobanking should therefore emphasize prosocial reasons to consent.


Assuntos
Bancos de Espécimes Biológicos , Conhecimentos, Atitudes e Prática em Saúde , Consentimento Livre e Esclarecido , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Compreensão , Tomada de Decisões , Feminino , Humanos , Consentimento Livre e Esclarecido/ética , Consentimento Livre e Esclarecido/psicologia , Masculino , Pessoa de Meia-Idade , Motivação , Inquéritos e Questionários , Obtenção de Tecidos e Órgãos/ética , Adulto Jovem
11.
Appl Environ Microbiol ; 83(22)2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28887422

RESUMO

Hanseniaspora uvarum (anamorph Kloeckera apiculata) is a predominant yeast on wine grapes and other fruits and has a strong influence on wine quality, even when Saccharomyces cerevisiae starter cultures are employed. In this work, we sequenced and annotated approximately 93% of the H. uvarum genome. Southern and synteny analyses were employed to construct a map of the seven chromosomes present in a type strain. Comparative determinations of specific enzyme activities within the fermentative pathway in H. uvarum and S. cerevisiae indicated that the reduced capacity of the former yeast for ethanol production is caused primarily by an ∼10-fold-lower activity of the key glycolytic enzyme pyruvate kinase. The heterologous expression of the encoding gene, H. uvarumPYK1 (HuPYK1), and two genes encoding the phosphofructokinase subunits, HuPFK1 and HuPFK2, in the respective deletion mutants of S. cerevisiae confirmed their functional homology.IMPORTANCEHanseniaspora uvarum is a predominant yeast species on grapes and other fruits. It contributes significantly to the production of desired as well as unfavorable aroma compounds and thus determines the quality of the final product, especially wine. Despite this obvious importance, knowledge on its genetics is scarce. As a basis for targeted metabolic modifications, here we provide the results of a genomic sequencing approach, including the annotation of 3,010 protein-encoding genes, e.g., those encoding the entire sugar fermentation pathway, key components of stress response signaling pathways, and enzymes catalyzing the production of aroma compounds. Comparative analyses suggest that the low fermentative capacity of H. uvarum compared to that of Saccharomyces cerevisiae can be attributed to low pyruvate kinase activity. The data reported here are expected to aid in establishing H. uvarum as a non-Saccharomyces yeast in starter cultures for wine and cider fermentations.


Assuntos
Etanol/metabolismo , Proteínas Fúngicas/metabolismo , Genoma Fúngico , Hanseniaspora/genética , Hanseniaspora/metabolismo , Piruvato Quinase/metabolismo , Vitis/microbiologia , Fermentação , Proteínas Fúngicas/genética , Glicólise , Hanseniaspora/enzimologia , Piruvato Quinase/genética
12.
Front Cell Dev Biol ; 5: 20, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28361052

RESUMO

The long bones of vertebrate limbs form by endochondral ossification, whereby mesenchymal cells differentiate into chondrogenic progenitors, which then differentiate into chondrocytes. Chondrocytes undergo further differentiation from proliferating to prehypertrophic, and finally to hypertrophic chondrocytes. Several signaling pathways and transcription factors regulate this process. Previously, we and others have shown in chicken that overexpression of an activated form of Calcium/calmodulin-dependent kinase II (CaMKII) results in ectopic chondrocyte maturation. Here, we show that this is not the case in the mouse. Although, in vitro Mef2c activity was upregulated by about 55-fold in response to expression of an activated form of CaMKII (DACaMKII), transgenic mice that expressed a dominant-active form of CaMKII under the control of the Col2a1 regulatory elements display only a very transient and mild phenotype. Here, only the onset of chondrocyte hypertrophy at E12.5 is accelerated. It is also this early step in chondrocyte differentiation that is temporarily delayed around E13.5 in transgenic mice expressing the peptide inhibitor CaM-KIIN from rat (rKIIN) under the control of the Col2a1 regulatory elements. Yet, ultimately DACaMKII, as well as rKIIN transgenic mice are born with completely normal skeletal elements with regard to their length and growth plate organization. Hence, our in vivo analysis suggests that CaMKII signaling plays a minor role in chondrocyte maturation in mice.

13.
Vaccine ; 27(12): 1834-40, 2009 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-19200448

RESUMO

This study evaluates the forces involved in the adsorption of abagovomab onto an aluminium hydroxide adjuvant in interstitial fluid and the influences of interstitial fluid and its components on this process. Abagovomab is a monoclonal, anti-idiotypic antibody developed as an immunovaccine for the treatment of ovarian cancer. Partial elution of abagovomab by a change in ionic strength indicates that electrostatic interactions influenced adsorption. Studies on the role of phosphate and simulated interstitial fluid on the adsorption demonstrated that ligand exchange is the main force of adsorption. A comparison of the adsorption capacity of abagovomab in the formulation with that in an environment imitating the in vivo environment using simulated interstitial fluid showed the adsorption capacity to decrease, the more the conditions resemble the in vivo environment after subcutaneous or intramuscular administration.


Assuntos
Adjuvantes Imunológicos/química , Hidróxido de Alumínio/química , Anticorpos Monoclonais/química , Líquido Extracelular/química , Adsorção , Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais Murinos , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/química , Eletroquímica , Ensaio de Imunoadsorção Enzimática , Etilenoglicol/química , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Focalização Isoelétrica , Termodinâmica
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