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1.
Nat Commun ; 15(1): 1251, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341437

RESUMO

Organismal functional strategies form a continuum from slow- to fast-growing organisms, in response to common drivers such as resource availability and disturbance. However, whether there is synchronisation of these strategies at the entire community level is unclear. Here, we combine trait data for >2800 above- and belowground taxa from 14 trophic guilds spanning a disturbance and resource availability gradient in German grasslands. The results indicate that most guilds consistently respond to these drivers through both direct and trophically mediated effects, resulting in a 'slow-fast' axis at the level of the entire community. Using 15 indicators of carbon and nutrient fluxes, biomass production and decomposition, we also show that fast trait communities are associated with faster rates of ecosystem functioning. These findings demonstrate that 'slow' and 'fast' strategies can be manifested at the level of whole communities, opening new avenues of ecosystem-level functional classification.


Assuntos
Biodiversidade , Ecossistema , Biomassa , Agricultura , Solo
2.
Liver Int ; 43(12): 2668-2679, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37534777

RESUMO

BACKGROUND AND AIMS: The presence of significant liver fibrosis associated with non-alcoholic steatohepatitis (NASH) is regarded as the major prognostic factor in non-alcoholic fatty liver disease (NAFLD). Identification of patients at risk for NASH with significant fibrosis is therefore important. Although the established fibrosis score FIB-4 is suitable to exclude advanced fibrosis, it does not allow the prediction of significant fibrosis in NAFLD patients. We therefore evaluated whether the hepatokine fibroblast growth factor 21 (FGF21), a regulator of glucose and lipid metabolism, might identify 'at-risk NASH' in NAFLD. METHODS: FGF21 levels were assessed by enzyme-linked immunosorbent assay in sera from an exploration (n = 137) and a validation (n = 88) cohort of biopsy-proven NAFLD patients with different disease activity and fibrosis stages. In addition, we evaluated whether the use of FGF21 could improve risk stratification in NAFLD patients with low (<1.3) or intermediate (1.3-2.67) FIB-4. RESULTS: FGF21 levels could significantly discriminate between NASH and non-alcoholic fatty liver (NAFL) patients, even in the absence of diabetes. Moreover, patients with NASH and fibrosis ≥F2 showed significantly higher FGF21 levels compared to NAFLD patients without significant fibrosis. Significantly elevated FGF21 levels could even be detected in NAFLD patients with NASH and significant fibrosis despite low or intermediate FIB-4. CONCLUSION: Serological FGF21 detection might allow the identification of NAFLD patients at risk and improves patient stratification in combination with FIB-4.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Cirrose Hepática/patologia , Fibrose , Medição de Risco , Fígado/patologia , Biópsia
3.
J Autoimmun ; 138: 103057, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37224732

RESUMO

The forkhead family transcription factor (FOXP3) is an essential regulator for the development of regulatory T cells (Tregs) and orchestrates both suppressive function and Treg lineage identity. Stable expression of FOXP3 enables Tregs to maintain immune homeostasis and prevent autoimmunity. However, under pro-inflammatory conditions, FOXP3 expression in Tregs can become unstable, leading to loss of suppressive function and conversion into pathogenic T effector cells. Therefore, the success of adoptive cell therapy with chimeric antigen receptor (CAR) Tregs is highly dependent on the stability of FOXP3 expression to ensure the safety of the cell product. To warrant the stable expression of FOXP3 in CAR-Treg products, we have developed an HLA-A2-specific CAR vector that co-expresses FOXP3. The transduction of isolated human Tregs with the FOXP3-CAR led to an increase in the safety and efficacy of the CAR-Treg product. In a hostile microenvironment, under pro-inflammatory and IL-2-deficient conditions, FOXP3-CAR-Tregs showed a stable expression of FOXP3 compared to Control-CAR-Tregs. Furthermore, additional exogenous expression of FOXP3 did not induce phenotypic alterations and dysfunctions such as cell exhaustion, loss of functional Treg characteristics or abnormal cytokine secretion. In a humanized mouse model, FOXP3-CAR-Tregs displayed an excellent ability to prevent allograft rejection. Furthermore, FOXP3-CAR-Tregs revealed coherent Treg niche-filling capabilities. Overexpression of FOXP3 in CAR-Tregs has thereby the potential to increase the efficacy and reliability of cellular products, promoting their clinical use in organ transplantation and autoimmune diseases.


Assuntos
Doenças Autoimunes , Receptores de Antígenos Quiméricos , Animais , Humanos , Camundongos , Doenças Autoimunes/genética , Doenças Autoimunes/terapia , Doenças Autoimunes/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Reprodutibilidade dos Testes , Linfócitos T Reguladores
4.
J Clin Med ; 11(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956017

RESUMO

Background: Non-alcoholic steatohepatitis (NASH) and fibrosis are the main prognostic factors in non-alcoholic fatty liver disease (NAFLD). The FIB-4 score has been suggested as an initial test for the exclusion of progressed fibrosis. However, increasing evidence suggests that also NASH patients with earlier fibrosis stages are at risk of disease progression, emphasizing the need for improved non-invasive risk stratification. Methods: We evaluated whether the apoptosis biomarker M30 can identify patients with fibrotic NASH despite low or intermediate FIB-4 values. Serum M30 levels were assessed by ELISA, and FIB-4 was calculated in an exploration (n = 103) and validation (n = 100) cohort of patients with histologically confirmed NAFLD. Results: The majority of patients with low FIB-4 (cut-off value < 1.3) in the exploration cohort revealed increased M30 levels (>200 U/L) and more than 80% of them had NASH, mostly with fibrosis. NASH was also detected in all patients with intermediate FIB-4 (1.3 to 2.67) and elevated M30, from which ~80% showed fibrosis. Importantly, in the absence of elevated M30, most patients with FIB-4 < 1.3 and NASH showed also no fibrosis. Similar results were obtained in the validation cohort. Conclusions: The combination of FIB-4 with M30 enables a more reliable identification of patients at risk for progressed NAFLD and might, therefore, improve patient stratification.

5.
Br J Haematol ; 196(3): 681-689, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34617271

RESUMO

Sporadic Burkitt lymphoma (BL) is the most frequent tumour of children and adolescents but a rare subtype of lymphomas in adults. To date most molecular data have been obtained from lymphomas arising in the young. Recently, Epstein-Barr virus (EBV) positive and negative BL in young patients was shown to differ in molecular features. In the present study, we present a large age-overarching cohort of sporadic BL (n = 162) analysed by immunohistochemistry, translocations of MYC proto-oncogene, basic helix-loop-helix transcription factor (MYC), B-cell leukaemia/lymphoma 2 (BCL2) and B-cell leukaemia/lymphoma 6 (BCL6) and by targeted sequencing. We illustrate an age-associated inter-tumoral molecular heterogeneity in this disease. Mutations affecting inhibitor of DNA binding 3, HLH protein (ID3), transcription factor 3 (TCF3) and cyclin D3 (CCND3), which are highly recurrent in paediatric BL, and expression of sex determining region Y-box transcription factor 11 (SOX11) declined with patient age at diagnosis (P = 0·0204 and P = 0·0197 respectively). In contrast, EBV was more frequently detected in adult patients (P = 0·0262). Irrespective of age, EBV-positive sporadic BL showed significantly less frequent mutations in ID3/TCF3/CCND3 (P = 0·0088) but more often mutations of G protein subunit alpha 13 (GNA13; P = 0·0368) and forkhead box O1 (FOXO1; P = 0·0044) compared to EBV-negative tumours. Our findings suggest that among sporadic BL an EBV-positive subgroup of lymphomas increases with patient age that shows distinct pathogenic features reminiscent of EBV-positive endemic BL.


Assuntos
Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/etiologia , Suscetibilidade a Doenças , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/fisiologia , Mutação , Adolescente , Adulto , Fatores Etários , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Linfoma de Burkitt/diagnóstico , Transformação Celular Viral , Criança , Pré-Escolar , Análise Mutacional de DNA , Infecções por Vírus Epstein-Barr/virologia , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Front Immunol ; 12: 705485, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305946

RESUMO

Therapeutics that block tumor necrosis factor (TNF), and thus activation of TNF receptor 1 (TNFR1) and TNFR2, are clinically used to treat inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease and psoriasis. However, TNFR1 and TNFR2 work antithetically to balance immune responses involved in inflammatory diseases. In particular, TNFR1 promotes inflammation and tissue degeneration, whereas TNFR2 contributes to immune modulation and tissue regeneration. We, therefore, have developed the monovalent antagonistic anti-TNFR1 antibody derivative Atrosimab to selectively block TNFR1 signaling, while leaving TNFR2 signaling unaffected. Here, we describe that Atrosimab is highly stable at different storage temperatures and demonstrate its therapeutic efficacy in mouse models of acute and chronic inflammation, including experimental arthritis, non-alcoholic steatohepatitis (NASH) and experimental autoimmune encephalomyelitis (EAE). Our data support the hypothesis that it is sufficient to block TNFR1 signaling, while leaving immune modulatory and regenerative responses via TNFR2 intact, to induce therapeutic effects. Collectively, we demonstrate the therapeutic potential of the human TNFR1 antagonist Atrosimab for treatment of chronic inflammatory diseases.


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Fatores Imunológicos/farmacologia , Receptores Tipo I de Fatores de Necrose Tumoral/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia
7.
Cell Death Dis ; 12(8): 736, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312366

RESUMO

Hepatocellular carcinoma (HCC) represents a global health challenge with limited therapeutic options. Anti-angiogenic immune checkpoint inhibitor-based combination therapy has been introduced for progressed HCC, but improves survival only in a subset of HCC patients. Tyrosine-kinase inhibitors (TKI) such as sorafenib represent an alternative treatment option but have only modest efficacy. Using different HCC cell lines and HCC tissues from various patients reflecting HCC heterogeneity, we investigated whether the sorafenib response could be enhanced by combination with pro-apoptotic agents, such as TNF-related apoptosis-inducing ligand (TRAIL) or the BH3-mimetic ABT-737, which target the death receptor and mitochondrial pathway of apoptosis, respectively. We found that both agents could enhance sorafenib-induced cell death which was, however, dependent on specific BH3-only proteins. TRAIL augmented sorafenib-induced cell death only in NOXA-expressing HCC cells, whereas ABT-737 enhanced the sorafenib response also in NOXA-deficient cells. ABT-737, however, failed to augment sorafenib cytotoxicity in the absence of BIM, even when NOXA was strongly expressed. In the presence of NOXA, BIM-deficient HCC cells could be in turn strongly sensitized for cell death induction by the combination of sorafenib with TRAIL. Accordingly, HCC tissues sensitive to apoptosis induction by sorafenib and TRAIL revealed enhanced NOXA expression compared to HCC tissues resistant to this treatment combination. Thus, our results suggest that BH3-only protein expression determines the treatment response of HCC to different sorafenib-based drug combinations. Individual profiling of BH3-only protein expression might therefore assist patient stratification to certain TKI-based HCC therapies.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Sorafenibe/uso terapêutico , Apoptose/efeitos dos fármacos , Proteína 11 Semelhante a Bcl-2/metabolismo , Compostos de Bifenilo/farmacologia , Carcinoma Hepatocelular/patologia , Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Antígeno Ki-67/metabolismo , Neoplasias Hepáticas/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Nitrofenóis/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sorafenibe/farmacologia , Sulfonamidas/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia
8.
Nat Commun ; 12(1): 3918, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168127

RESUMO

Land-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity.


Assuntos
Biodiversidade , Ecossistema , Plantas , Microbiologia do Solo , Agricultura , Animais , Europa (Continente) , Cadeia Alimentar , Florestas , Pradaria , Herbivoria , Insetos
9.
Arch Toxicol ; 94(10): 3527-3539, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651653

RESUMO

Amiodarone is a widely used antiarrhythmic drug that can cause the development of steatohepatitis as well as liver fibrosis and cirrhosis. The molecular mechanisms of amiodarone-mediated liver injury remain largely unknown. We therefore analyzed amiodarone-mediated hepatocellular injury in patients with chronic heart failure, in primary hepatocytes and HepG2 cells. We found that amiodarone-treated patients with chronic heart failure revealed significantly higher serum levels of caspase-cleaved keratin-18, an apoptosis biomarker, compared to healthy individuals or patients not receiving amiodarone. Furthermore, amiodarone treatment of hepatocytes resulted in apoptosis associated with lipid accumulation and ER-stress induction. Liver cell steatosis was accompanied by enhanced de novo lipogenesis which, after reaching peak levels, declined together with decreased activation of ER stress. The decline of amiodarone-mediated lipotoxicity was associated with protective autophagy induction. In contrast, in hepatocytes treated with the autophagy inhibitor chloroquine as well as in autophagy gene (ATG5 or ATG7)-deficient hepatocytes, amiodarone-triggered toxicity was increased. In conclusion, we demonstrate that amiodarone induces lipid accumulation associated with ER stress and apoptosis in hepatocytes, which is mirrored by increased keratin-18 fragment serum levels in amiodarone-treated patients. Autophagy reduces amiodarone-mediated lipotoxicity and could provide a therapeutic strategy for protection from drug-induced liver injury.


Assuntos
Amiodarona/efeitos adversos , Autofagia , Doença Hepática Induzida por Substâncias e Drogas , Hepatócitos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Idoso , Antiarrítmicos/efeitos adversos , Apoptose/efeitos dos fármacos , Sistemas CRISPR-Cas , Sobrevivência Celular , Células Cultivadas , Cloroquina/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Técnicas de Inativação de Genes , Células Hep G2 , Humanos , Queratina-18/sangue , Masculino
10.
Cell Death Dis ; 11(3): 212, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32235829

RESUMO

Non-alcoholic fatty liver disease (NAFLD) shows an increasing prevalence and is associated with the development of liver fibrosis and cirrhosis as the major risk factors of liver-related mortality in this disease. The therapeutic possibilities are limited and restricted to life style intervention, since specific drugs for NAFLD are unavailable so far. TNFα has been implicated as a major pathogenic driver of NAFLD. TNFα-mediated liver injury occurs mainly via TNF-receptor-1 (TNFR1) signaling, whereas TNFR2 mediates protective pathways. In this study, we analyzed the therapeutic effects of a novel antibody, which selectively inhibits TNFR1 while retaining protective TNFR2 signaling in a high-fat diet (HFD) mouse model of NAFLD. Mice were fed with HFD for 32 weeks and treated with anti-TNFR1-antibody or control-antibody for the last 8 weeks. We then investigated the mechanisms of TNFR1 inhibition on liver steatosis, inflammatory liver injury, insulin resistance and fibrosis. Compared to control-antibody treatment, TNFR1 inhibition significantly reduced liver steatosis and triglyceride content, which was accompanied by reduced expression and activation of the transcription factor SREBP1 and downstream target genes of lipogenesis. Furthermore, inhibition of TNFR1 resulted in reduced activation of the MAP kinase MKK7 and its downstream target JNK, which was associated with significant improvement of insulin resistance. Apoptotic liver injury, NAFLD activity and alanine aminotransferase (ALT) levels, as well as liver fibrosis significantly decreased by anti-TNFR1 compared to control-antibody treatment. Thus, our results suggest selective TNFR1 inhibition as a promising approach for NAFLD treatment.


Assuntos
Fígado Gorduroso/terapia , Cirrose Hepática/terapia , Hepatopatia Gordurosa não Alcoólica/terapia , Fator 1 Associado a Receptor de TNF/antagonistas & inibidores , Animais , Fígado Gorduroso/genética , Humanos , Cirrose Hepática/genética , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/genética
11.
Sci Total Environ ; 710: 136352, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31927290

RESUMO

Increasing water scarcity and rapid socio-economic development are driving farmers in Asia to transform traditionally flooded rice cropping systems into non-flooded crop production. The management of earthworms in non-flooded rice fields appears to be a promising strategy to support residue recycling and mitigate greenhouse gas (GHG) emissions triggered by residue amendment. We conducted a field experiment on non-flooded rainfed rice fields, with and without residue amendment. In-situ mesocosms were inoculated with endogeic earthworms (Metaphire sp.), with either low (ET1: 150 individuals m-2), or high density (ET2: 450 individuals m-2), and a control (ET0: no earthworms). We measured GHG emissions (methane (CH4); nitrous oxide (N2O); carbon dioxide (CO2)) twice a week during the cropping season with static chambers. Effects of earthworms on yield and root growth were additionally assessed. Earthworms offset the enormous increase of CH4 emissions induced by straw amendment (from 4.6 ± 5 to 75.3 ± 46 kg CH4-C ha-1 in ET0). Earthworm activity significantly reduced CH4 release, particularly at ET2, by more than one-third (to 22 ± 15 kg CH4-C ha-1). In contrast, earthworm inoculation did not affect N2O emission. Straw amendment more than doubled the global warming potential (GWP). Earthworms reduced GWP by 39% at low (ET1) and 55% at high densities (ET2). Earthworm activity reduced root mass density under conditions of straw amendment but did not affect yield. Earthworms can significantly reduce detrimental effects of rice crop residue amendment on GHG release under upland rice production. Organic carbon (C) might be preserved in earthworm casts and thereby limit C availability for CH4 production. At the same time, earthworm activity might increase methanotrophic CH4 consumption, due to improved soil aeration or less root exudates. Consequently, earthworms have a strong potential for regulating ecosystem functions related to rice straw decomposition, nutrient allocation and thus GHG reduction.


Assuntos
Gases de Efeito Estufa , Oligoquetos , Oryza , Agricultura , Animais , Ásia , Aquecimento Global , Metano , Óxido Nitroso , Solo
12.
Sci Rep ; 9(1): 10197, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308442

RESUMO

Rice growing requires highly destructive and highly invasive field management negatively affecting soil biota and its functions. We aimed to compare taxonomic and functional trait compositions of soil macrofauna at different stages of rice cropping cycles in the three temperate rice-growing regions in Russia. Samples were collected in 2016 at four different biotopes in each region: flooded rice paddies; upland crops planted one year after flooded rice; rice paddy bunds; and relatively undisturbed seminatural control grasslands. Collected soil macrofauna were allocated to different traits according to their feeding preferences, vertical distribution, mobility and flood tolerance. The lowest macrofaunal abundance across all regions was observed in rice paddies. Cultivation of upland crops after paddy flooding consistently decreased the abundance of resident macrofauna, but not that of mobile soil macrofauna. In the upland crops, the abundance of belowground and mobile belowground macrofauna was significantly higher than that in control grasslands. The abundance of aboveground phytophages was significantly lower in the upland crops than in control sites. Flood-associated taxa showed low colonization ability after the paddies were drained. In contrast, representatives of other traits recorded in flooded fields increased their abundance at the next stage of crop rotation, demonstrating high resilience within an entire rice-growing system, including bunds. This finding indicates a high potential of seminatural grasslands and especially bunds as sources of rapid restoration of soil macrofauna functional diversity in rice-growing agroecosystems, thus maintaining the sustainability of soil food webs in the rice paddies.


Assuntos
Agricultura/métodos , Oryza/microbiologia , Microbiologia do Solo , Produtos Agrícolas/microbiologia , Ecossistema , Solo/química
14.
J Infect Dis ; 213(5): 746-54, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26503984

RESUMO

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and associated complications such as liver cirrhosis and hepatocellular carcinoma. Interferons (IFNs) are crucial for HCV clearance and a sustained virological response (SVR), but a significant proportion of patients do not respond to IFNα. The underlying mechanisms of an insufficient IFN response remain largely unknown. In this study, we found that patients responding to IFNα with viral clearance had significantly higher serum levels of TNF-related apoptosis inducing ligand (TRAIL), compared with patients who failed to control HCV. In addition, upon direct IFNα exposure, peripheral blood mononuclear cells (PBMCs) from patients with SVR upregulated TRAIL, as well as IFN-γ and the chemokines CXCL9 and CXCL10, much more strongly than cells from patients with antiviral treatment failure. As a possible mechanism of the stronger IFNα-induced cytokine response, we identified higher levels of expression and phosphorylation of the transcription factor STAT1 in PBMCs from patients with SVR. Increased TRAIL expression additionally involved the NF-κB and JNK signaling pathways. Thus, SVR in chronic HCV infection is associated with a strong IFNα-induced cytokine response, which might allow for the early prediction of treatment efficacy in HCV infection.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Adulto , Citocinas/genética , Feminino , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Leucócitos Mononucleares , Fígado/metabolismo , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Masculino , Pessoa de Meia-Idade , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/fisiologia , Falha de Tratamento
15.
PLoS One ; 10(7): e0134402, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26225556

RESUMO

Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil) on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices.


Assuntos
Irrigação Agrícola , Biodegradação Ambiental , Oryza/crescimento & desenvolvimento , Animais , Invertebrados/metabolismo
16.
Eur J Cancer ; 51(12): 1596-602, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26048456

RESUMO

Squamous cell cancer of the head and neck (SCCHN) is a frequent aggressive malignancy with limited therapeutic options. Increasing evidence suggests that mammalian target of rapamycin (mTOR)-inhibitors might be effective in advanced SCCHN. However, non-invasive biomarkers for early prediction of treatment efficacy are not established in SCCHN. Highly proliferating tumours are characterised by enhanced cell turnover which is associated with enhanced apoptosis. During apoptosis of epithelial cells caspases cleave cytokeratin (CK)-18 can be detected in the blood. In this study we analysed sera from patients with relapsed or metastatic SCCHN patients who have been treated with temsirolimus for caspase-cleaved and total (caspase-cleaved and uncleaved) CK-18 by enzyme-linked immunosorbent assays (ELISAs). In addition, caspase-3 activity was detected by luminometric substrate assay. SCCHN patients revealed higher serum levels of those biomarkers compared to healthy controls. Importantly, patients with short progression-free survival (PFS) showed higher serum levels of caspase-3 activity compared to patients with longer PFS (⩾ 2months). Caspase-3 activity is inversely correlated with PFS. A cut-off value for caspase-3 activity was determined that correctly predicted PFS <2months with a sensitivity of 86% and a specificity of 67%. These data demonstrate that detection of serum caspase-3 activity might be a useful non-invasive biomarker for early identification of SCCHN patients not responding to treatment with novel targeted therapies such as mTOR-inhibitors.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/tratamento farmacológico , Caspases/sangue , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Sirolimo/análogos & derivados , Idoso , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/enzimologia , Intervalo Livre de Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sirolimo/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço
17.
Hepatology ; 60(4): 1346-55, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24913549

RESUMO

UNLABELLED: Acute liver failure (ALF) represents a life-threatening situation characterized by sudden and massive liver cell death in the absence of preexisting liver disease. Although most patients require liver transplantation to prevent mortality, some recover spontaneously and show complete liver regeneration. Because of the rarity of this disease, the molecular mechanisms regulating liver regeneration in ALF patients remain largely unknown. In this study, we investigated the role of microRNAs (miRs) that have been implicated in liver injury and regeneration in sera from ALF patients (n = 63). Patients with spontaneous recovery from ALF showed significantly higher serum levels of miR-122, miR-21, and miR-221, compared to nonrecovered patients. In liver biopsies, miR-21 and miR-221 displayed a reciprocal expression pattern and were found at lower levels in the spontaneous survivors, whereas miR-122 was elevated in both serum and liver tissue of those patients. As compared to nonrecovered patients, liver tissue of spontaneous survivors revealed not only increased hepatocyte proliferation, but also a strong down-regulation of miRNA target genes that impair liver regeneration, including heme oxygenase-1, programmed cell death 4, and the cyclin-dependent kinase inhibitors p21, p27, and p57. CONCLUSION: Our data suggest that miR-122, miR-21, and miR-221 are involved in liver regeneration and might contribute to spontaneous recovery from ALF. Prospective studies will show whether serological detection of those miRNAs might be of prognostic value to predict ALF outcome.


Assuntos
Falência Hepática Aguda/fisiopatologia , Regeneração Hepática/fisiologia , MicroRNAs/fisiologia , Recuperação de Função Fisiológica/fisiologia , Adulto , Biomarcadores/sangue , Biópsia , Estudos de Casos e Controles , Proliferação de Células , Feminino , Hepatócitos/patologia , Humanos , Fígado/patologia , Falência Hepática Aguda/sangue , Falência Hepática Aguda/mortalidade , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Taxa de Sobrevida
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