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1.
Sci Total Environ ; 927: 171927, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556006

RESUMO

Rivers are important transport pathways for microplastics into the ocean, but they can also be potential sinks due to microplastic deposition in the sediments of the river bed and adjacent floodplains. In particular, floods can (re)mobilise microplastics from sediments and floodplains, (re)deposit and relocate them depending on the floodplain topography. The knowledge about fluvial microplastic input to floodplains, their spatial distribution and their fate in floodplain soils is limited. To investigate this topic, we sampled soil at a depth of 5-20 cm along three transects in three different Rhine floodplains. We analysed the soil samples in tandem with pyrolysis GC/MS and ATR- & µ-FPA-FTIR for their microplastic abundance and mass concentrations. To study the influence of flood frequency on the microplastic abundance in the three floodplains, we fitted a hydrodynamic flood model (MIKE 21, DHI, Hørsholm, Denmark) and related the results to the respective spatial microplastic distribution. We found similar microplastic distribution patterns in each floodplain. The highest microplastic abundance (8516-70,124 microplastics kg-1) and mass concentration (46.2-141.6 mg kg-1) were consistently found in the farthest transects from the Rhine in a topographical depression. This microplastic distribution pattern is detectable with both, pyrolysis GC/MS and FTIR. The strongest correlation between the results of both methods was found for small, abundant microplastic particles. Our results suggest that the spatial distribution of microplastics in floodplains is related to the combination of flood frequency and local topography, that ought to be explicitly considered in future studies conducted in floodplains. Finally, our results indicate that pyrolysis GC/MS and FTIR data are comparable under certain conditions, which may help in the decision for the analytical method and sampling design in future studies.

2.
Nat Commun ; 14(1): 5143, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612308

RESUMO

Replicative stress promotes genomic instability and tumorigenesis but also presents an effective therapeutic endpoint, rationalizing detailed analysis of pathways that control DNA replication. We show here that the transcription factor E2f4 recruits the DNA helicase Recql to facilitate progression of DNA replication forks upon drug- or oncogene-induced replicative stress. In unperturbed cells, the Trim33 ubiquitin ligase targets E2f4 for degradation, limiting its genomic binding and interactions with Recql. Replicative stress blunts Trim33-dependent ubiquitination of E2f4, which stimulates transient Recql recruitment to chromatin and facilitates recovery of DNA synthesis. In contrast, deletion of Trim33 induces chronic genome-wide recruitment of Recql and strongly accelerates DNA replication under stress, compromising checkpoint signaling and DNA repair. Depletion of Trim33 in Myc-overexpressing cells leads to accumulation of replication-associated DNA damage and delays Myc-driven tumorigenesis. We propose that the Trim33-E2f4-Recql axis controls progression of DNA replication forks along transcriptionally active chromatin to maintain genome integrity.


Assuntos
Predisposição Genética para Doença , RecQ Helicases , Humanos , Cromatina/genética , Equipamento de Proteção Individual , Carcinogênese , Transformação Celular Neoplásica
3.
Clin Oral Investig ; 27(10): 5841-5851, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37561212

RESUMO

OBJECTIVE: The objective of this clinical trial was to compare facial expressions (magnitude, shape change, time, and symmetry) before (T0) and after (T1) orthognathic surgery by implementing a novel method of four-dimensional (4D) motion capture analysis, known as videostereophotogrammetry, in orthodontics. METHODS: This prospective, single-centre, single-arm trial included a total of 26 adult patients (mean age 28.4 years; skeletal class II: n = 13, skeletal class III: n = 13) with indication for orthodontic-surgical treatment. Two reproducible facial expressions (maximum smile, lip purse) were captured at T0 and T1 by videostereophotogrammetry as 4D face scan. The magnitude, shape change, symmetry, and time of the facial movements were analysed. The motion changes were analysed in dependence of skeletal class and surgical movements. RESULTS: 4D motion capture analysis was feasible in all cases. The magnitude of the expression maximum smile increased from 15.24 to 17.27 mm (p = 0.002), while that of the expression lip purse decreased from 9.34 to 8.31 mm (p = 0.01). Shape change, symmetry, and time of the facial movements did not differ significantly pre- and postsurgical. The changes in facial movements following orthodontic-surgical treatment were observed independently of skeletal class and surgical movements. CONCLUSIONS: Orthodontic-surgical treatment not only affects static soft tissue but also soft tissue dynamics while smiling or lip pursing. CLINICAL RELEVANCE: To achieve comprehensive orthodontic treatment plans, the integration of facial dynamics via videostereophotogrammetry provides a promising approach in diagnostics. TRIAL REGISTRATION NUMBER: DRKS00017206.


Assuntos
Má Oclusão Classe III de Angle , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Adulto , Humanos , Cefalometria/métodos , Expressão Facial , Má Oclusão Classe III de Angle/cirurgia , Movimento , Procedimentos Cirúrgicos Ortognáticos/métodos , Estudos Prospectivos , Sorriso
4.
Int J Mol Sci ; 23(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35269711

RESUMO

Mesenchymal stem cells (MSCs) gain an increasing focus in the field of regenerative medicine due to their differentiation abilities into chondrocytes, adipocytes, and osteoblastic cells. However, it is apparent that the transformation processes are extremely complex and cause cellular heterogeneity. The study aimed to characterize differences between MSCs and cells after adipogenic (AD) or osteoblastic (OB) differentiation at the proteome level. Comparative proteomic profiling was performed using tandem mass spectrometry in data-independent acquisition mode. Proteins were quantified by deep neural networks in library-free mode and correlated to the Molecular Signature Database (MSigDB) hallmark gene set collections for functional annotation. We analyzed 4108 proteins across all samples, which revealed a distinct clustering between MSCs and cell differentiation states. Protein expression profiling identified activation of the Peroxisome proliferator-activated receptors (PPARs) signaling pathway after AD. In addition, two distinct protein marker panels could be defined for osteoblastic and adipocytic cell lineages. Hereby, overexpression of AEBP1 and MCM4 for OB as well as of FABP4 for AD was detected as the most promising molecular markers. Combination of deep neural network and machine-learning algorithms with data-independent mass spectrometry distinguish MSCs and cell lineages after adipogenic or osteoblastic differentiation. We identified specific proteins as the molecular basis for bone formation, which could be used for regenerative medicine in the future.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Adipogenia/genética , Diferenciação Celular/genética , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Proteômica
5.
J Adolesc Health ; 64(4S): S45-S51, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30914168

RESUMO

PURPOSE: Child marriages and unions can infringe upon adolescent and youth sexual and reproductive health (AYSRH). Interventions increasingly promote strategies to transform social norms or foster the agency of adolescent girls. Recent empirical studies call for further understanding of how social norms and agency interact in ways that influence these practices, especially in contexts where girls' agency is central. METHODS: A secondary cross-case analysis of three qualitative studies (in Brazil, Guatemala, Honduras) was conducted to inform the investigation of how norms and agency may relate in sustaining or mitigating child marriage. RESULTS: Social norms dictating how girls/young women and how men should act indirectly led to child marriages and unions. The data showed that (1) social norms regulated girls' acceptable actions and contributed to their exercise of "oppositional" agency; (2) social norms promoted girls' "accommodating" agency; and (3) girls exercised "transformative" agency to resist harmful social norms. CONCLUSIONS: Research should advance frameworks to conceptualize how social norms interact with agency in nuanced and context-specific ways. Practitioners should encourage equitable decision-making; offer confidential, adolescent-friendly AYSRH services; and address the social norms of parents, men and boys, and community members.


Assuntos
Tomada de Decisões , Casamento/psicologia , Normas Sociais , Adolescente , Adulto , Fatores Etários , Brasil , Criança , Feminino , Grupos Focais , Guatemala , Honduras , Humanos , Casamento/estatística & dados numéricos , Pessoa de Meia-Idade , Relações Pais-Filho , Pesquisa Qualitativa , Comportamento Sexual , Adulto Jovem
6.
Ann Hematol ; 91(10): 1579-86, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22752146

RESUMO

We analyzed the safety and efficacy of rituximab plus bendamustine (R-B) in elderly and frail patients with aggressive B-non-Hodgkin lymphoma (a-B-NHL). Few reports have as yet reported on R-B in a-B-NHL, albeit its value for indolent lymphoma vs. R-CHOP has impressively been shown. We assessed 20 consecutive patients with a-B-NHL receiving R-B as first-line or relapse treatment after (R)-CHOP in our department. Besides patient- and lymphoma-specific characteristics, comorbidity indices were determined. The median patient age was 72 years (51-86), the median Karnofsky performance status was 55 % (40-90 %), and according to the international prognostic index, 15 had high-intermediate or high-risk disease. The comorbidity indices revealed a median Kaplan-Feinstein index of 3 (range 1-3), Charlson comorbidity index of 4 (range 0-9), hematopoietic cell transplantation-specific comorbidity index of 3 (range 0-11), and Freiburg comorbidity index of 2 (range 0-2). Moreover, eight patients had echocardiographic and laboratory signs of cardiac insufficiency, all leading to R-B rather than R-CHOP treatment. The overall response rate was 55 %, with complete response and partial response rates of 20 and 35 %, respectively. In our frail and elderly patient cohort, R-B therapy was well-tolerated. Median progression free survival and overall survival were 8.3 months (95 % confidence interval [CI], 2.8--not reached [n.r.]) and 19.4 months (95 % CI, 4.6--n.r.), respectively. We conclude that R-B is a feasible and safe therapy option in a-B-NHL patients not qualifying for R-CHOP but needs to be further assessed in larger subsequent trials, these currently being under way.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Idoso Fragilizado , Linfoma de Células B/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cloridrato de Bendamustina , Tolerância a Medicamentos , Feminino , Seguimentos , Humanos , Linfoma de Células B/mortalidade , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Compostos de Mostarda Nitrogenada/administração & dosagem , Compostos de Mostarda Nitrogenada/efeitos adversos , Rituximab , Taxa de Sobrevida/tendências , Resultado do Tratamento
7.
Thromb Haemost ; 104(6): 1201-10, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20978712

RESUMO

Septins are cytoskeletal GTPases forming heteropolymeric complexes involved in processes characterised by active membrane movement such as cytokinesis, vesicle trafficking, and exocytosis. Septins are expressed in non-mitotic cells such as neurons and platelets. SEPT11 belongs to the SEPT6 group and was identified as interaction partner of SEPT5. We cloned and characterised novel SEPT11 variants and investigated interaction partners of SEPT11 in platelets and human umbilical vein endothelial cells. An endothelial cell library was used for cloning novel SEPT11 variants. Using Northern analysis the different SEPT11 transcripts were illustrated. Interaction studies were performed using yeast two-hybrid system, precipitation, FRET, and immunofluorescence microscopy. We demonstrate that SEPT11 partners with SEPT2, SEPT4 and SEPT7 using yeast two-hybrid system and precipitation. The interaction of SEPT11 with SEPT7 is also demonstrated by FRET. In addition to the known SEPT11 transcript (SEPT11_v1) we identified a novel SEPT11 variant (SEPT11_v2) as interaction partner of SEPT4 and SEPT7. Library screening of an endothelial cell library also revealed the presence of this novel SEPT11_v2 transcript. In addition, a third SEPT11 variant (SEPT11_v3) was identified. Expression of SEPT11_v1 and of SEPT11_v2 and SEPT11_v3 in human brain regions was investigated by Northern analysis. Further interaction partners of SEPT11 are characterised using immunofluorescence. Co-localisation of SEPT2, SEPT4, SEPT7 and SEPT11 with tubulin and transferrin receptor (endocytotic marker) is demonstrated. In addition, co-localisation of SEPT4 and SEPT11 with the vesicle-associated protein synaptobrevin 1 (VAMP1), but not clearly with actin, was shown. Only SEPT2 and SEPT7 definitely co-localised with actin, but not clearly with VAMP1.


Assuntos
Plaquetas/enzimologia , Células Endoteliais/enzimologia , Septinas/metabolismo , Actinas/metabolismo , Processamento Alternativo , Northern Blotting , Proteínas de Ciclo Celular/metabolismo , Clonagem Molecular , Transferência Ressonante de Energia de Fluorescência , Biblioteca Gênica , Humanos , Microscopia de Fluorescência , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Receptores da Transferrina/metabolismo , Septinas/genética , Tubulina (Proteína)/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Proteína 1 Associada à Membrana da Vesícula/metabolismo
8.
Hum Immunol ; 71(9): 916-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20538026

RESUMO

Cartilage hair hypoplasia (CHH) is an autosomal recessive disorder caused by mutations in the ribonuclease mitochondrial RNA-processing (RMRP) gene. Although its most constant feature is metaphyseal dysplasia with short stature, CHH is associated with extraskeletal defects such as thin hair, anemia, immunodeficiency, and increased incidence of lymphomas. The spectrum of immunologic phenotypes in CHH translates into clinical severity. Whereas T-cell deficiency may remain subclinical or may result in severe combined immunodeficiency or Omenn syndrome, humoral immunodeficiency has only rarely been noted in these patients. Here we report the diagnosis of CHH in a woman who presented with severe short stature and a full-blown antibody deficiency, clinically resembling common variable immunodeficiency. Sequencing of the RMRP gene revealed compound heterozygosity for two novel mutations (g.68_69delinsTT and g.76C>T). Despite the late onset of immunodeficiency in the patient, its clinical course was severe, and the patient died 3 years after the first diagnosis.


Assuntos
Endorribonucleases/genética , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/genética , Adulto , Agamaglobulinemia/sangue , Idade de Início , Anticorpos/sangue , Anticorpos/imunologia , Sequência de Bases/genética , Medula Óssea/patologia , Bronquiectasia/patologia , Líquido da Lavagem Broncoalveolar/microbiologia , Evolução Fatal , Feminino , Transtornos do Crescimento/patologia , Cabelo/anormalidades , Cabelo/imunologia , Cabelo/patologia , Deformidades Congênitas da Mão/patologia , Doença de Hirschsprung/complicações , Doença de Hirschsprung/genética , Doença de Hirschsprung/imunologia , Doença de Hirschsprung/patologia , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/patologia , Contagem de Linfócitos , Masculino , Mutação/genética , Osteocondrodisplasias/complicações , Osteocondrodisplasias/congênito , Osteocondrodisplasias/genética , Osteocondrodisplasias/imunologia , Osteocondrodisplasias/patologia , Pneumonia/imunologia , Pneumonia/patologia , Doenças da Imunodeficiência Primária , Sepse/imunologia , Sepse/patologia , Esplenomegalia/patologia
9.
J Immunol ; 182(6): 3349-56, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19265111

RESUMO

Tolerogenic dendritic cells (DC) play an important role in maintaining peripheral T cell tolerance in steady-state conditions through induction of anergic, IL-10-producing T cells with suppressive properties. ICOS, an activation-induced member of the CD28 family on T cells, is involved in the induction of IL-10, which itself could contribute to induction of anergy and development of suppressive T cells. Therefore, we analyzed the functional role of ICOS in the differentiation process of human CD4(+) T cells upon their interaction with tolerogenic DC. We compared the functional properties of CD4(+) T cells from healthy volunteers and ICOS-deficient patients after stimulation with tolerogenic DC. We report that induction of T cell anergy and suppressive capacity is completely blocked after knockdown of ICOS expression in T cells as well as after blocking of ICOS-ICOS ligand interaction in DC/T cell cocultures. Moreover, CD4(+) T cells from ICOS-deficient patients were completely resistant to anergy induction and differentiation into suppressive T cells even after supplementation of IL-10. Furthermore, ICOS/ICOS ligand interaction stabilizes IL-10R expression on T cells and thus renders them sensitive to IL-10 effects. Taken together, these results indicate a crucial role for ICOS in the induction of peripheral tolerance maintained by tolerogenic DC mediated mostly via an IL-10-independent mechanism.


Assuntos
Antígenos de Diferenciação de Linfócitos T/fisiologia , Anergia Clonal/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Antígenos de Diferenciação de Linfócitos T/genética , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Anergia Clonal/genética , Técnicas de Cocultura , Imunodeficiência de Variável Comum/genética , Imunodeficiência de Variável Comum/imunologia , Imunodeficiência de Variável Comum/patologia , Células Dendríticas/patologia , Técnicas de Silenciamento de Genes , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis , Interleucina-10/fisiologia , Ativação Linfocitária/genética , Linfócitos T/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
10.
Clin Immunol ; 122(2): 156-62, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17137841

RESUMO

Common Variable Immunodeficiency (CVID) patients who are seropositive for anti-IgA antibodies have a predisposition for anaphylactoid reactions to intravenous immunoglobulin replacement therapy (IVIG). Among 88 CVID patients, we identified eight with IgG anti-IgA antibodies (9%). All eight completely lacked IgA (<0.0009 g/l). Five of them had a history of anaphylactoid reactions to IVIG. However, four of these five patients tolerated subcutaneous immunoglobulin replacement therapy (SCIG). To identify predisposing factors for anti-IgA antibodies and related anaphylactoid reactions, we analyzed the clinical and immunological phenotype of affected patients. All eight IgG anti-IgA-positive patients lacked IgA(+) B cells in peripheral blood. Moreover, CVID patients with retained class-switched CD27(pos) IgM(neg) IgD(neg) memory B cells (Freiburg classification group II) and total IgA deficiency seem to have an increased risk for developing anti-IgA antibodies. In seven of the eight patients, lymphoproliferation was observed (most prominently nodular lymphatic hyperplasia), two had granulomatous disease, and two showed autoimmune phenomena.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Imunodeficiência de Variável Comum/diagnóstico , Imunodeficiência de Variável Comum/terapia , Imunoglobulina A/imunologia , Adulto , Anafilaxia/imunologia , Imunodeficiência de Variável Comum/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulinas Intravenosas , Masculino , Pessoa de Meia-Idade
11.
Int Arch Allergy Immunol ; 140(4): 342-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16757923

RESUMO

BACKGROUND/AIMS: Common variable immunodeficiency (CVID) is the most common primary immunodeficiency. With respect to underlying defects it comprises a heterogeneous group of deficiencies. For some patients, distinct phenotypical abnormalities have been described, e.g. partial CD40L deficiency or complete ICOS deficiency. For the diagnosis of CD40L deficiency, a rapid whole blood flow cytometric method has been described several years ago. We aimed to determine if the same method can be used to diagnose ICOS deficiency. METHODS: Whole blood from 8 healthy volunteers was stimulated for 4 and 20 h with phorbol 12-myristate 13-acetate (PMA) and ionomycin. Induction of ICOS expression was analyzed on CD8-CD3+ lymphocytes using three-color flow cytometry. Blood from a patient with diagnosed ICOS deficiency was also analyzed. RESULTS: Whole-blood stimulation with PMA and ionomycin for 20 h resulted in a significant induction of ICOS expression on CD8-CD3+ lymphocytes in healthy volunteers. Four-hour incubation also demonstrated ICOS upregulation but to a much lower extent. In CD8-CD3+ lymphocytes from an ICOS-deficient patient, no ICOS expression could be induced following 20 h of stimulation. CONCLUSION: ICOS expression can be analyzed using a rapid whole blood flow cytometric test.


Assuntos
Antígenos de Diferenciação de Linfócitos T/sangue , Imunodeficiência de Variável Comum/sangue , Citometria de Fluxo/métodos , Antígenos CD/sangue , Antígenos de Diferenciação de Linfócitos T/metabolismo , Complexo CD3/sangue , Linfócitos T CD8-Positivos/química , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Imunodeficiência de Variável Comum/patologia , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis , Ionomicina/farmacologia , Lectinas Tipo C , Acetato de Tetradecanoilforbol/farmacologia
12.
Thromb Haemost ; 91(5): 959-66, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15116257

RESUMO

Septins are a family of GTP-binding proteins, which are essential for active membrane movement such as cytokinesis and vesicle trafficking. In non-dividing cells (such as platelets and neurons) septins are implicated in exocytosis. Platelets from a SEPT5 knockout mouse showed an altered serotonin secretion and platelet aggregation, suggesting that SEPT5 is involved in secretion in platelets. Septins form complexes consisting of multiple septin polypeptides. Using the yeast two-hybrid system we had demonstrated that SEPT5 partners with SEPT8. The aim of this study was to identify other interaction partners of the human platelet septin SEPT8. Using the yeast two-hybrid system with SEPT8 as bait protein we identified the human septin SEPT4 as an interaction partner of SEPT8. The interaction between SEPT4 and SEPT8 was confirmed by immunoprecipitation. Expression analysis revealed that SEPT4 is also expressed in human platelets. Thus, SEPT4 is the third described platelet septin besides SEPT5 and SEPT8. Transmission electron microscopy of platelets revealed that SEPT8 and SEPT4 are localized surrounding alpha-granules (as it had been shown for the septin SEPT5) suggesting that the three septins may be components of the septin complex in platelets and contribute in such a way to platelet biology. Activation of platelets by agonists resulted in the translocation of SEPT4 and SEPT8 to the platelet surface indicating a possible functional role of these proteins in platelet granular secretion.


Assuntos
Plaquetas/química , Proteínas do Citoesqueleto/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Proteínas de Membrana/metabolismo , Mapeamento de Interação de Proteínas , Plaquetas/fisiologia , Plaquetas/ultraestrutura , Proteínas do Citoesqueleto/fisiologia , GTP Fosfo-Hidrolases/fisiologia , Biblioteca Gênica , Humanos , Substâncias Macromoleculares , Proteínas de Membrana/fisiologia , Ligação Proteica , Transporte Proteico , Vesículas Secretórias/química , Septinas , Técnicas do Sistema de Duplo-Híbrido
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