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1.
Gastroenterology ; 165(2): 374-390, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37196797

RESUMO

BACKGROUND & AIMS: Elements of field cancerization, including atrophic gastritis, metaplasia, and dysplasia, promote gastric cancer development in association with chronic inflammation. However, it remains unclear how stroma changes during carcinogenesis and how the stroma contributes to progression of gastric preneoplasia. Here we investigated heterogeneity of fibroblasts, one of the most important elements in the stroma, and their roles in neoplastic transformation of metaplasia. METHODS: We used single-cell transcriptomics to evaluate the cellular heterogeneity of mucosal cells from patients with gastric cancer. Tissue sections from the same cohort and tissue microarrays were used to identify the geographical distribution of distinct fibroblast subsets. We further evaluated the role of fibroblasts from pathologic mucosa in dysplastic progression of metaplastic cells using patient-derived metaplastic gastroids and fibroblasts. RESULTS: We identified 4 subsets of fibroblasts within stromal cells defined by the differential expression of PDGFRA, FBLN2, ACTA2, or PDGFRB. Each subset was distributed distinctively throughout stomach tissues with different proportions at each pathologic stage. The PDGFRα+ subset expanded in metaplasia and cancer compared with normal, maintaining a close proximity with the epithelial compartment. Co-culture of metaplasia- or cancer-derived fibroblasts with gastroids showing the characteristics of spasmolytic polypeptide-expressing metaplasia-induced disordered growth, loss of metaplastic markers, and increases in markers of dysplasia. Culture of metaplastic gastroids with conditioned media from metaplasia- or cancer-derived fibroblasts also promoted dysplastic transition. CONCLUSIONS: These findings indicate that fibroblast associations with metaplastic epithelial cells can facilitate direct transition of metaplastic spasmolytic polypeptide-expressing metaplasia cell lineages into dysplastic lineages.


Assuntos
Mucosa Gástrica , Neoplasias Gástricas , Humanos , Mucosa Gástrica/patologia , Neoplasias Gástricas/patologia , Hiperplasia , Metaplasia/patologia , Fibroblastos/metabolismo
2.
PLoS Biol ; 17(8): e3000399, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31381560

RESUMO

Most models of cancer cell population expansion assume exponential growth kinetics at low cell densities, with deviations to account for observed slowing of growth rate only at higher densities due to limited resources such as space and nutrients. However, recent preclinical and clinical observations of tumor initiation or recurrence indicate the presence of tumor growth kinetics in which growth rates scale positively with cell numbers. These observations are analogous to the cooperative behavior of species in an ecosystem described by the ecological principle of the Allee effect. In preclinical and clinical models, however, tumor growth data are limited by the lower limit of detection (i.e., a measurable lesion) and confounding variables, such as tumor microenvironment, and immune responses may cause and mask deviations from exponential growth models. In this work, we present alternative growth models to investigate the presence of an Allee effect in cancer cells seeded at low cell densities in a controlled in vitro setting. We propose a stochastic modeling framework to disentangle expected deviations due to small population size stochastic effects from cooperative growth and use the moment approach for stochastic parameter estimation to calibrate the observed growth trajectories. We validate the framework on simulated data and apply this approach to longitudinal cell proliferation data of BT-474 luminal B breast cancer cells. We find that cell population growth kinetics are best described by a model structure that considers the Allee effect, in that the birth rate of tumor cells increases with cell number in the regime of small population size. This indicates a potentially critical role of cooperative behavior among tumor cells at low cell densities with relevance to early stage growth patterns of emerging and relapsed tumors.


Assuntos
Contagem de Células/métodos , Proliferação de Células/fisiologia , Neoplasias/metabolismo , Linhagem Celular Tumoral , Ecossistema , Humanos , Cinética , Modelos Biológicos , Modelos Teóricos
3.
Nature ; 535(7611): 299-302, 2016 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-27411635

RESUMO

The mechanisms underlying haematopoietic lineage decisions remain disputed. Lineage-affiliated transcription factors with the capacity for lineage reprogramming, positive auto-regulation and mutual inhibition have been described as being expressed in uncommitted cell populations. This led to the assumption that lineage choice is cell-intrinsically initiated and determined by stochastic switches of randomly fluctuating cross-antagonistic transcription factors. However, this hypothesis was developed on the basis of RNA expression data from snapshot and/or population-averaged analyses. Alternative models of lineage choice therefore cannot be excluded. Here we use novel reporter mouse lines and live imaging for continuous single-cell long-term quantification of the transcription factors GATA1 and PU.1 (also known as SPI1). We analyse individual haematopoietic stem cells throughout differentiation into megakaryocytic-erythroid and granulocytic-monocytic lineages. The observed expression dynamics are incompatible with the assumption that stochastic switching between PU.1 and GATA1 precedes and initiates megakaryocytic-erythroid versus granulocytic-monocytic lineage decision-making. Rather, our findings suggest that these transcription factors are only executing and reinforcing lineage choice once made. These results challenge the current prevailing model of early myeloid lineage choice.


Assuntos
Diferenciação Celular , Linhagem da Célula , Fator de Transcrição GATA1/metabolismo , Células Mieloides/citologia , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo , Animais , Eritrócitos/citologia , Retroalimentação Fisiológica , Feminino , Genes Reporter , Granulócitos/citologia , Hematopoese , Células-Tronco Hematopoéticas/citologia , Masculino , Megacariócitos/citologia , Camundongos , Modelos Biológicos , Monócitos/citologia , Reprodutibilidade dos Testes , Análise de Célula Única , Processos Estocásticos
4.
Sedimentology ; 68(6): 2365-2396, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34690376

RESUMO

Remobilization and deformation of surficial subaqueous slope sediments create turbidites and soft sediment deformation structures, which are common features in many depositional records. Palaeoseismic studies have used seismically-induced turbidites and soft sediment deformation structures preserved in sedimentary sequences to reconstruct recurrence patterns and - in some cases - allow quantifying rupture location and magnitude of past earthquakes. However, current understanding of earthquake-triggered remobilization and deformation lacks studies targeting where these processes take place, the subaqueous slope and involving direct comparison of sedimentary fingerprint with well-documented historical earthquakes. This study investigates the sedimentary imprint of six megathrust earthquakes with varying rupture characteristics in 17 slope sediment cores from two Chilean lakes, Riñihue and Calafquén, and evaluates how it links to seismic intensity, peak ground acceleration, bracketed duration and slope angle. Centimetre-scale stratigraphic gaps ranging from ca 1 to 20 cm - caused by remobilization of surficial slope sediment - were identified using high-resolution multi-proxy core correlation of slope to basin cores, and six types of soft sediment deformation structures ranging from ca 1 to 25 cm thickness using high-resolution three-dimensional X-ray computed tomography data. Stratigraphic gaps occur on slope angles of ≥2.3°, whereas deformation already occurs from slope angle 0.2°. The thickness of both stratigraphic gaps and soft sediment deformation structures increases with slope angle, suggesting that increased gravitational shear stress promotes both surficial remobilization and deformation. Seismic shaking is the dominant trigger for surficial remobilization and deformation at the studied lakes. Total remobilization depth correlates best with bracketed duration and is highest in both lakes for the strongest earthquakes (M w ca 9.5). In lake Riñihue, soft sediment deformation structure thickness and type correlate best with peak ground acceleration providing the first field-based evidence of progressive soft sediment deformation structure development with increasing peak ground acceleration for soft sediment deformation structures caused by Kelvin-Helmholtz instability. The authors propose that long duration and low frequency content of seismic shaking favours surficial remobilization, whereas ground motion amplitude controls Kelvin-Helmholtz instability-related soft sediment deformation structure development.

5.
Nat Methods ; 14(4): 403-406, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28218899

RESUMO

Differentiation alters molecular properties of stem and progenitor cells, leading to changes in their shape and movement characteristics. We present a deep neural network that prospectively predicts lineage choice in differentiating primary hematopoietic progenitors using image patches from brightfield microscopy and cellular movement. Surprisingly, lineage choice can be detected up to three generations before conventional molecular markers are observable. Our approach allows identification of cells with differentially expressed lineage-specifying genes without molecular labeling.


Assuntos
Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Imagem com Lapso de Tempo/métodos , Animais , Área Sob a Curva , Biomarcadores/metabolismo , Diferenciação Celular , Linhagem da Célula , Técnicas de Introdução de Genes , Aprendizado de Máquina , Masculino , Camundongos Mutantes , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/genética , Transativadores/metabolismo
6.
Liver Int ; 40(8): 1872-1882, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32378295

RESUMO

BACKGROUND & AIMS: Approximately one-third of patients with non-alcoholic fatty liver disease (NAFLD) show signs of mild-to-moderate iron overload. The impact of histological iron deposition on the clinical course of patients with NAFLD has not been established. METHODS & RESULTS: For this retrospective study, 299 consecutive patients with biopsy-proven NAFLD and a mean follow-up of 8.4 (±4.1; range: 0.3-18.0) years were allocated to one of four groups according to presence of hepatic iron in the reticuloendothelial system (RES) and/or hepatocytes (HC): 156 subjects (52%) showed no stainable iron (NONE), 58 (19%) exclusively reticuloendothelial (xRES), 19 (6%) exclusively hepatocellular (xHC) and 66 (22%) showed a mixed (HC/RES) pattern of iron deposition. A long-term analysis for overall survival, hepatic, cardiovascular or extrahepatic-malignant events was conducted. Based on multivariate Cox proportional hazards models any reticuloendothelial iron was associated with fatal and non-fatal hepatic events. Specifically, xRES showed a cause-specific hazard ratio (csHR) of 2.4 (95%-CI, 1.0-5.8; P = .048) for hepatic as well as cardiovascular fatal and non-fatal events combined (csHR 3.2; 95%-CI, 1.2-8.2; P = .015). Furthermore, the mixed HC/RES iron pattern showed a higher rate of combined hepatic fatal and non-fatal events (csHR 3.6; 95%-CI, 1.4-9.5; P = .010), while xHC iron deposition was not associated with any defined events. CONCLUSIONS: The presence of reticuloendothelial-accentuated hepatic iron distribution patterns is associated with detrimental long-term outcomes reflected in a higher rate of both liver-related and cardiovascular fatal and non-fatal events.


Assuntos
Sobrecarga de Ferro , Hepatopatia Gordurosa não Alcoólica , Humanos , Ferro , Fígado , Estudos Retrospectivos
7.
Geophys Res Lett ; 46(11): 6015-6023, 2019 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-31423037

RESUMO

Strong earthquakes at active ocean margins can remobilize vast amounts of surficial slope sediments and dynamically strengthen the margin sequences. Current process understanding is obtained from resulting event deposits and low-resolution shear strength data, respectively. Here we directly target a site offshore Japan where both processes are expected to initiate, that is, at the uppermost part (15 cm) of a sedimentary slope sequence. Based on a novel application of short-lived radionuclide data, we identified, dated, and quantified centimeter-scale gaps related to surficial remobilization. Temporal correlation to the three largest regional earthquakes attest triggering by strong earthquakes (M w >8). Also, extremely elevated shear strength values suggest a strong influence of seismic strengthening on shallow sediments. We show that despite enhanced slope stability by seismic strengthening, earthquake-induced sediment transport can occur through surficial remobilization, which has large implications for the assessment of turbidite paleoseismology and carbon cycling at active margins.

8.
Liver Int ; 38(7): 1188-1197, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29197145

RESUMO

BACKGROUND & AIMS: Excellent efficacy and safety profile of second-generation DAA combinations improved treatment of chronic hepatitis C (HCV) as well as in HCV recurrence after orthotopic liver transplantation (OLT). The need of ribavirin addition is under debate as anaemia and decreased renal function are prevalent in transplant cohorts. The aim of this study was thus to assess safety and long-term efficacy of RBV-free DAA combinations in HCV-recurrent patients after OLT. PATIENTS & METHODS: A total of 62 OLT recipients (male: 50%/81%; age: 60.7 ± 8.5 years [mean ± SD]; GT - 1: 48, GT - 3: 9, GT - 4: 5; cirrhosis: 34%/55% [7%/21% decompensated], fibrosing cholestatic hepatitis: 1%/2%) received RBV-free treatment with second-generation DAA combinations: sofosbuvir (SOF)/daclatasvir (DCV): 42%/68%, SOF/simeprevir (SMV): 10%/16%, SOF/ledipasvir (LDV): 6%/10% and PrOD: 4%/7%. RESULTS: Data of at least 96 weeks of FUP after treatment cessation (mean: 120; up to 167 weeks) were analysed. All patients showed on-treatment response. By intention-to-treat (ITT) analysis, SVR12 was 97% (60/62, GT-1a: 11/11 [100%]; 1b: 33/34 [97%]; 1g: 1/1 [100%]; subtype not specified: 2/2 [100%]; GT3a: 9/9 [100%]; GT4: 4/5 [80%]) compared to SVR96 of 89% (55/62). No late relapses occurred. In total, 16 severe adverse events occurred, including two newly diagnosed carcinoma (lung cancer, hepatocellular carcinoma). Six patients died; one at treatment week 24 (HCV-RNA undetectable) and five during treatment-free FUP and after achieving SVR (SVR4: N = 1, SVR12: N = 3, after SVR96: N = 1 respectively). Reasons for death were: multi-organ failure (N = 4), impaired graft function (N = 1) and unknown (N = 1). CONCLUSION: RBV-free DAA combinations for the treatment of HCV recurrence after OLT are highly efficacious and well tolerated. Our long-term data show that viral eradication is durable but not necessarily translated into beneficial long-term clinical outcome.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Transplante de Fígado , Idoso , Áustria , Benzimidazóis/uso terapêutico , Carbamatos , Carcinoma Hepatocelular/virologia , Quimioterapia Combinada , Feminino , Fluorenos/uso terapêutico , Seguimentos , Hepacivirus/genética , Hepatite C Crônica/complicações , Hepatite C Crônica/mortalidade , Humanos , Imidazóis/uso terapêutico , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Pirrolidinas , Recidiva , Ribavirina , Simeprevir/uso terapêutico , Sofosbuvir/uso terapêutico , Resposta Viral Sustentada , Valina/análogos & derivados
9.
Liver Int ; 38(6): 1028-1035, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29136329

RESUMO

BACKGROUND: The introduction of direct-acting antivirals (DAA) has increased sustained virological response (SVR) rates in patients with advanced liver disease and chronic hepatitis C(CHC)infection. At present, data on clinical outcome and long-term durability of viral eradication after successful DAA therapy are scarce. AIM: To evaluate the long-term success of viral eradication in patients with advanced fibrosis or cirrhosis treated with DAAs. METHODS: Five hundred and fifty-one patients with advanced fibrosis (n = 158) or cirrhosis (CPS-A:317,CPS-B/C:76) and SVR after interferon and ribavirin-free DAA therapy treated between October 2013 and April 2016 were studied with a median follow-up of 65.6 (13.0-155.3) weeks. Only patients without hepatocellular carcinoma (HCC) at baseline and without liver transplantation were included. RESULTS: Twelve patients (2.2%) died during follow-up: the mortality rate was 0.6% in F3, 2.2% in CPS-A and 5.3% in CPS-B/C patients (P = .08). During follow-up 36 patients with cirrhosis (9.1%) developed a liver related event, including 16 with de-novo HCC (4.1%). Seven patients were transplanted at a median of 9.7 (range 3.8-21.7) months after EOT. History of decompensation was significantly associated with liver related events during follow-up (HR 7.9; 95% CI 2.7-22.6; P < .001), and with mortality (HR 5.5; 95% CI 1.5-20.2, P = .01). CONCLUSIONS: Eradication of HCV by DAA therapy was durable irrespective of the DAA combination used. Most of the cured patients had an excellent long-term clinical prognosis. Nevertheless, the risk of new occurrence of HCC remains worrisome and thus regular surveillance is obligatory even after clinical stabilization and improvement of the patient.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/complicações , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Idoso , Áustria , Carcinoma Hepatocelular/virologia , Feminino , Seguimentos , Hepatite C Crônica/mortalidade , Humanos , Interferons , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Ribavirina , Resposta Viral Sustentada
10.
Phys Biol ; 14(3): 036001, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28198357

RESUMO

Accessing gene expression at a single-cell level has unraveled often large heterogeneity among seemingly homogeneous cells, which remains obscured when using traditional population-based approaches. The computational analysis of single-cell transcriptomics data, however, still imposes unresolved challenges with respect to normalization, visualization and modeling the data. One such issue is differences in cell size, which introduce additional variability into the data and for which appropriate normalization techniques are needed. Otherwise, these differences in cell size may obscure genuine heterogeneities among cell populations and lead to overdispersed steady-state distributions of mRNA transcript numbers. We present cgCorrect, a statistical framework to correct for differences in cell size that are due to cell growth in single-cell transcriptomics data. We derive the probability for the cell-growth-corrected mRNA transcript number given the measured, cell size-dependent mRNA transcript number, based on the assumption that the average number of transcripts in a cell increases proportionally to the cell's volume during the cell cycle. cgCorrect can be used for both data normalization and to analyze the steady-state distributions used to infer the gene expression mechanism. We demonstrate its applicability on both simulated data and single-cell quantitative real-time polymerase chain reaction (PCR) data from mouse blood stem and progenitor cells (and to quantitative single-cell RNA-sequencing data obtained from mouse embryonic stem cells). We show that correcting for differences in cell size affects the interpretation of the data obtained by typically performed computational analysis.


Assuntos
Crescimento Celular , Tamanho Celular , Perfilação da Expressão Gênica/métodos , Expressão Gênica , RNA Mensageiro/metabolismo , Biologia Computacional , Modelos Genéticos
11.
Hum Mol Genet ; 23(14): 3883-90, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24556216

RESUMO

Genome-wide association studies (GWAS) have revealed genetic determinants of iron metabolism, but correlation of these with clinical phenotypes is pending. Homozygosity for HFE C282Y is the predominant genetic risk factor for hereditary hemochromatosis (HH) and may cause liver cirrhosis. However, this genotype has a low penetrance. Thus, detection of yet unknown genetic markers that identify patients at risk of developing severe liver disease is necessary for better prevention. Genetic loci associated with iron metabolism (TF, TMPRSS6, PCSK7, TFR2 and Chr2p14) in recent GWAS and liver fibrosis (PNPLA3) in recent meta-analysis were analyzed for association with either liver cirrhosis or advanced fibrosis in 148 German HFE C282Y homozygotes. Replication of associations was sought in additional 499 Austrian/Swiss and 112 HFE C282Y homozygotes from Sweden. Only variant rs236918 in the PCSK7 gene (proprotein convertase subtilisin/kexin type 7) was associated with cirrhosis or advanced fibrosis (P = 1.02 × 10(-5)) in the German cohort with genotypic odds ratios of 3.56 (95% CI 1.29-9.77) for CG heterozygotes and 5.38 (95% CI 2.39-12.10) for C allele carriers. Association between rs236918 and cirrhosis was confirmed in Austrian/Swiss HFE C282Y homozygotes (P = 0.014; ORallelic = 1.82 (95% CI 1.12-2.95) but not in Swedish patients. Post hoc combined analyses of German/Swiss/Austrian patients with available liver histology (N = 244, P = 0.00014, ORallelic = 2.84) and of males only (N = 431, P = 2.17 × 10(-5), ORallelic = 2.54) were consistent with the premier finding. Association between rs236918 and cirrhosis was not confirmed in alcoholic cirrhotics, suggesting specificity of this genetic risk factor for HH. PCSK7 variant rs236918 is a risk factor for cirrhosis in HH patients homozygous for the HFE C282Y mutation.


Assuntos
Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Cirrose Hepática/genética , Proteínas de Membrana/genética , Subtilisinas/genética , Idoso , Feminino , Genoma Humano , Estudo de Associação Genômica Ampla , Hemocromatose/complicações , Hemocromatose/patologia , Proteína da Hemocromatose , Homozigoto , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
12.
Liver Int ; 36(1): 119-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26256590

RESUMO

BACKGROUND & AIMS: Liver biopsy (LB) is performed if non-invasive work-up of liver disease is inconclusive. The examination of liver tissue occasionally reveals normal histology. Long-term follow-up of such patients has not been performed. METHODS: We identified a total 70 subjects from our LB database with elevated liver tests and normal liver histology after a mean of 90.5 ± 52.3 (range 15-216) months and conducted reassessment of medical history, physical examination, laboratory testing, ultrasound, transient elastography and LB if indicated. RESULTS: At follow-up examination, 15 (7 females (f)/8 males (m); 21.4%) subjects had normal liver tests and no further evidence of liver disease. A subset of 37 (29 f/8 m; 52.9%) subjects had persistently elevated liver tests without evidence indicating progressive liver disease but the cause thereof remained unexplained also at the follow-up visit. Three (0 f/3 m; 4.3%) subjects had consumed excessive alcohol with indicators of alcoholic liver disease. Eleven subjects (4 f/7 m; 15.7%) had developed steatosis on ultrasound examination along with weight gain and/or biochemical features of the metabolic syndrome. In addition, three (2 f/1 m) patients developed autoimmune hepatitis, one female presented with primary biliary cirrhosis. One male was diagnosed with cholangiocellular carcinoma 3 months after the initial evaluation. CONCLUSION: The clinical course of most patients was benign, but in approximately 20% of the subjects a liver disease developed. Particular attention should be given to autoimmune liver diseases in subjects with positive autoantibodies. In addition, lifestyle factors such as weight gain and alcohol consumption were associated with the manifestation of liver diseases.


Assuntos
Consumo de Bebidas Alcoólicas , Hepatite Autoimune , Hepatopatias Alcoólicas , Hepatopatias , Fígado/patologia , Aumento de Peso , Adulto , Áustria/epidemiologia , Feminino , Seguimentos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/epidemiologia , Humanos , Hepatopatias/diagnóstico , Hepatopatias/epidemiologia , Hepatopatias/patologia , Hepatopatias Alcoólicas/diagnóstico , Hepatopatias Alcoólicas/epidemiologia , Testes de Função Hepática/métodos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Transpl Int ; 29(9): 999-1007, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27203857

RESUMO

DAA-based regimens for chronic hepatitis C infection encourage treatment of "difficult-to-treat" cohorts. This study investigated efficacy and safety of DAA-based regimens in HCV patients on dialysis or postkidney or liver/kidney transplantation. Twenty-five patients treated with DAA combinations were evaluated: 10 were on dialysis (eight: hemodialysis, two: peritoneal dialysis), eight were kidney transplant recipients, and seven were liver/kidney transplant recipients. Except for one patient treated with daclatasvir ([DCV]/60 mg/QD)/simeprevir ([SMV]/150 mg/QD), the others received sofosbuvir-based regimens ([SOF];400 mg/QD) combined with SMV:eight, DCV:13 or either ledipasvir ([LDV]90 mg/QD), ribavirin ([RBV];weight based) or pegylated interferon/RBV. HCV-RNA was determined by Abbott RealTime (LLOQ]:12 IU/ml) or Roche AmpliPrep/COBAS TaqMan assay (LLOQ:15 IU/ml); treatment response evaluated every 4 weeks, at the end of treatment, and 4 and 12 weeks thereafter. Twenty-four (96%) patients achieved SVR 12/24 (ITT-analysis). Mean treatment duration was 15.1 ± 5.1 weeks (±SD), and two patients terminated prematurely - both reached SVR12. Six patients were hospitalized due to complications of underlying disease. One patient achieved SVR24 but was re-infected (week 27). Kidney function remained stable; serum creatinine increased in only one patient - SOF was reduced to 400 mg/48 h. Treatment with DAA combinations in renally impaired HCV patients is highly effective and well tolerated. These findings call for further controlled trials and data from real-life cohorts.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Transplante de Rim , Insuficiência Renal/cirurgia , Adulto , Idoso , Benzimidazóis/uso terapêutico , Carbamatos , Estudos de Coortes , Quimioterapia Combinada , Feminino , Fluorenos/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/cirurgia , Humanos , Imidazóis/uso terapêutico , Imunossupressores/uso terapêutico , Rim/patologia , Testes de Função Renal , Fígado/patologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Pirrolidinas , RNA Viral/genética , Diálise Renal , Simeprevir/uso terapêutico , Sofosbuvir/uso terapêutico , Valina/análogos & derivados
14.
Phys Chem Chem Phys ; 18(6): 4994-5004, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26812175

RESUMO

Pump-probe transient extinction spectroscopy was used to analyze 355 nm picosecond laser heating-induced phenomena in 60 nm-diameter aqueous gold nanoparticles (AuNPs) under a high pressure of 60 MPa. Kinetic spectroscopy revealed that a supercritical layer surrounding the AuNP nucleated with a lifetime of approximately 1 ns during its dynamic expansion and decay for a fluence of 19.6 mJ cm(-2). Moreover, in the post-mortem transmission electron micrographs we observed a number of fragments, a small percentage of size-reduced cores, and erupted particles among the intact particles after 60 shots, suggesting that evaporation occurred under laser illumination. The particle temperature calculation indicated that evaporation begins with a liquid droplet AuNP surrounded by a supercritical layer at temperatures below the boiling point of gold. By applying high pressure, we obtained a clear picture of the evaporation event, which was not possible at ambient pressure because bubble formation caused particle temperatures to rise uncontrollably. In this study, we shed light on the critical role of the supercritical layer formed around the AuNP under high pressure during laser-induced evaporation.

15.
J Hepatol ; 63(1): 156-63, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25678388

RESUMO

BACKGROUND & AIMS: The earliest characteristic alterations of the liver pathology in Wilson disease (WD) include steatosis, which is sometimes indistinguishable from non-alcoholic fatty liver disease (NAFLD). Steatosis in WD may reflect copper-induced mitochondrial dysfunction. A genetic polymorphism in rs738409, in the patatin-like phospholipase domain-containing 3 gene (PNPLA3), is strongly associated with appearance of in NAFLD. This study evaluated the role of PNPLA3 and hepatic copper content for development of steatosis in patients with WD. METHODS: Liver biopsies obtained at diagnosis and the PNPLA3 genotype were analyzed in 98 Caucasian patients with WD (male: 52 [53.1%]; mean age: 27.6 years [CI 95%: 24.8-30.4, range: 5.8-61.5]). Steatosis was graded as percentage of lipid containing hepatocytes by an expert hepatopathologist unaware of the results of genetic testing. RESULTS: Moderate/severe steatosis (>33% of hepatocytes) was observed in 28 patients (pediatric: n=13/26 [50.0%], adult: n=15/72 [20.8%]; p=0.01). Forty-six patients (46.9%; pediatric: n=7, adult: n=39; p=0.022) had cirrhosis. Multivariate logistic regression identified PNPLA3 G allele (OR: 2.469, CI 95%: 1.203-5.068; p=0.014) and pediatric age (OR: 4.348; 1.577-11.905; p=0.004) as independent variables associated with moderate/severe steatosis. In contrast, hepatic copper content did not impact on moderate/severe steatosis (OR: 1.000, CI 95%: 1.000-1.001; p=0.297). CONCLUSIONS: Steatosis is common in WD and the PNPLA3 G allele contributes to its pathogenesis. The role of hepatic copper concentration and ATP7B mutations in steatosis development deserve further investigations.


Assuntos
Cobre/metabolismo , DNA/genética , Degeneração Hepatolenticular/genética , Lipase/genética , Fígado/metabolismo , Proteínas de Membrana/genética , Mutação , Adolescente , Adulto , Alelos , Biópsia , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Genótipo , Degeneração Hepatolenticular/metabolismo , Degeneração Hepatolenticular/patologia , Humanos , Lipase/metabolismo , Fígado/patologia , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Adulto Jovem
16.
Optom Vis Sci ; 92(4 Suppl 1): S40-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25756341

RESUMO

PURPOSE: Hereditary hyperferritinemia cataract syndrome (HHCS) is a rare autosomal dominant hereditary disease, characterized by hyperferritinemia but with absence of body iron excess and early onset of bilateral cataracts. Although 5- to 20-fold increased serum ferritin concentrations have been reported in HHCS patients, data of ferritin levels in aqueous humor have not been obtained. We therefore aimed to investigate the ferritin levels in aqueous humor and serum and further present histological and ultrastructural data of the lens. METHODS: During cataract extraction and intraocular lens implantation, aqueous humor and lens aspirate of a 37-year-old HHCS patient were obtained from both eyes. Ferritin levels in serum and aqueous humor were quantitatively analyzed via immunoassays in the HHCS patient and healthy control subjects (n = 6). Lens aspirate in HHCS was analyzed histologically and at the ultrastructural level. Further, genetic mutation screening by polymerase chain reaction and DNA sequencing in blood was performed. RESULTS: Serum ferritin levels in the control group were 142.2 ± 38.7 µg/L, whereas in the HHCS patient, this parameter was excessively increased (1086 µg/L). Analysis of ferritin in aqueous humor revealed 6.4 ± 3.8 µg/L in normal control subjects and 146.3 µg/L (OD) and 160.4 µg/L (OS) in the HHCS patient. DNA analysis detected a C>A mutation on position +18, a T>G mutation on position +22, a T>C mutation on position +24, and a T>G polymorphism on position +26 in the iron-responsive element of the light-chain ferritin (L-ferritin) gene. CONCLUSIONS: In the HHCS patient, a 23-fold (OD) to 25-fold (OS) increased aqueous humor ferritin level was detected. Therefore, the formation of bilateral cataract in HHCS is most likely a result of elevated aqueous humor ferritin. In addition, a novel mutation in this rare disease in the iron-responsive element of L-ferritin gene is reported.


Assuntos
Humor Aquoso/metabolismo , Catarata/congênito , Ferritinas/sangue , Distúrbios do Metabolismo do Ferro/congênito , Adulto , Catarata/metabolismo , Análise Mutacional de DNA , Ferritinas/genética , Humanos , Imunoensaio , Distúrbios do Metabolismo do Ferro/metabolismo , Implante de Lente Intraocular , Cristalino/patologia , Masculino , Mutação , Facoemulsificação , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
17.
Liver Int ; 34(3): 388-95, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23870067

RESUMO

BACKGROUND: In chronic hepatitis C (CHC), steatosis is associated with fibrosis and impaired response to antiviral therapy. Recently, a polymorphism of single nucleotide polymorphism SNP rs2645424 of farnesyl diphosphate farnesyl transferase 1 (FDFT1) was identified in NAFLD/NASH as a possible causal link to steatosis and fibrosis progression. SNP rs738409 in the adiponutrin gene (PNPLA3) is a well described factor for steatosis. This study evaluated the relation of these SNPs on steatosis, fibrosis and treatment response in CHC. METHODS: The SNPs rs738409478 and rs2645424 were determined by real-time PCR in 478 patients with CHC (m/f: 314/164; mean age: 44.9 ± 10.7; GT1: 387, GT4: 91) who completed treatment with peg-IFN-α-2a/ribavirin. All had a pretreatment liver biopsy. Steatosis and fibrosis were graded by board-certified pathologists according to Brunt and METAVIR respectively. RESULTS: The distribution of FDFT1 rs2645424 was GG: 186 (38.9%), AG: 222 (46.4%) and AA: 70 (14.6%) and of the rs738409 PNPLA3 allele: CC: 269 (56.3%), CG: 177 (37.0%) and GG: 32 (6.7%). Overall, FDTF1 polymorphism was not linked to the extent of steatosis or fibrosis. However, in patients without steatosis the AA genotype was associated with advanced fibrosis [AA: 8/20 (40.0%), AG: 6/70 (8.5%), GG: 9/57 (16.1%), P = 0.003]. In contrast, the minor PNPLA3 allele was associated with both steatosis and advanced fibrosis (P < 0.001). Both SNPs did not influence treatment response. CONCLUSION: The minor allele in FDFT1 was associated with advanced fibrosis in the non-steatotic but not in the steatotic subgroup. This may reflect different metabolic pathways in fibrosis progression for steatotic and non-steatotic patients with CHC.


Assuntos
Farnesil-Difosfato Farnesiltransferase/genética , Fígado Gorduroso/patologia , Hepatite C Crônica/genética , Cirrose Hepática/patologia , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Antivirais/uso terapêutico , Progressão da Doença , Feminino , Genótipo , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Fatores de Risco
18.
BMC Complement Altern Med ; 14: 115, 2014 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-24679099

RESUMO

BACKGROUND: Complementary and alternative medicine is often used by patients with malignant glioma. Although several interactions of various alternative agents with chemotherapy are known, none has been described for temozolomide so far. CASE PRESENTATION: We report the case of severe liver toxicity with jaundice during radiochemotherapy with temozolomide likely due to interaction with a popular Chinese herbal formula after surgery for glioblastoma. After cessation of the herbal formula as well as the chemotherapy liver enzymes slowly normalized. Due to tumor progression the patient was retreated with temozolomide for 5 cycles without toxicity. Because of further progression combination treatment of bevacizumab and irinotecan was started and again no liver toxicity was observed. CONCLUSIONS: We conclude that the observed toxicity with jaundice was probably caused by an interaction of this popular Chinese formula and temozolomide. This is the first report about a relevant interaction of temozolomide and any herbal formula.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas , Dacarbazina/análogos & derivados , Medicamentos de Ervas Chinesas/efeitos adversos , Glioblastoma/tratamento farmacológico , Interações Ervas-Drogas , Fígado/patologia , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Bevacizumab , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Terapia Combinada , Dacarbazina/uso terapêutico , Progressão da Doença , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Irinotecano , Pessoa de Meia-Idade , Fitoterapia/efeitos adversos , Temozolomida
19.
mSphere ; 9(1): e0033723, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38170974

RESUMO

Deep-sea and subseafloor sedimentary environments host heterotrophic microbial communities that contribute to Earth's carbon cycling. However, the potential metabolic functions of individual microorganisms and their biogeographical distributions in hadal ocean sediments remain largely unexplored. In this study, we conducted single-cell genome sequencing on sediment samples collected from six sites (7,445-8,023 m water depth) along an approximately 500 km transect of the Japan Trench during the International Ocean Discovery Program Expedition 386. A total of 1,886 single-cell amplified genomes (SAGs) were obtained, offering comprehensive genetic insights into sedimentary microbial communities in surface sediments (<1 m depth) above the sulfate-methane transition zone along the Japan Trench. Our genome data set included 269 SAGs from Atribacterota JS1, the predominant bacterial clade in these hadal environments. Phylogenetic analysis classified SAGs into nine distinct phylotypes, whereas metagenome-assembled genomes were categorized into only two phylotypes, advancing JS1 diversity coverage through a single cell-based approach. Comparative genomic analysis of JS1 lineages from different habitats revealed frequent detection of genes related to organic carbon utilization, such as extracellular enzymes like clostripain and α-amylase, and ABC transporters of oligopeptide from Japan Trench members. Furthermore, specific JS1 phylotypes exhibited a strong correlation with in situ methane concentrations and contained genes involved in glycine betaine metabolism. These findings suggest that the phylogenomically diverse and novel Atribacterota JS1 is widely distributed in Japan Trench sediment, playing crucial roles in carbon cycling within the hadal sedimentary biosphere.IMPORTANCEThe Japan Trench represents tectonically active hadal environments associated with Pacific plate subduction beneath the northeastern Japan arc. This study, for the first time, documented a large-scale single-cell and metagenomic survey along an approximately 500 km transect of the Japan Trench, obtaining high-quality genomic information on hadal sedimentary microbial communities. Single-cell genomics revealed the predominance of diverse JS1 lineages not recoverable through conventional metagenomic binning. Their metabolic potential includes genes related to the degradation of organic matter, which contributes to methanogenesis in the deeper layers. Our findings enhance understanding of sedimentary microbial communities at water depths exceeding 7,000 m and provide new insights into the ecological role of biogeochemical carbon cycling in the hadal sedimentary biosphere.


Assuntos
Bactérias , Microbiota , Japão , Filogenia , Bactérias/genética , Microbiota/genética , Genômica , Água , Carbono , Metano
20.
J Hepatol ; 59(5): 964-71, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23850877

RESUMO

BACKGROUND & AIMS: Single nucleotide polymorphisms (SNPs) in the inosine triphosphate pyrophosphatase (ITPA) gene protect patients from ribavirin induced anemia. To investigate other possible protective cofactors, gender differences were analyzed in patients with HCV genotype 1. METHODS: Hemoglobin levels at baseline (Hb0) and the decline after 4 weeks of treatment (HbΔ4) were analyzed in 308 chronic hepatitis C patients participating in 5 Austrian trials (n=308, age 43.9 ± 11.1, male:185, female:123, BMI 25.3 ± 3.9, no cirrhosis: n=259, liver cirrhosis: n=49). All patients were treated with 180 µg peginterferon-alpha 2a and ribavirin [1000-1200 mg/d; females: mean (95% CI) 15.8 mg/kg (15.4-16.2); males 14.3 (14.1-14.5); p<0.001]. The SNPs rs6051702, rs1127354, rs7270101 and IL28B rs12979860 were analyzed by the StepOnePlus Real time PCR System. RESULTS: 188 were major alleles homozygotes; 95 (30.8%) carried the minor allele (C) of rs6051702, 47 (15.3%) of rs1127354 (A), and 69 (22.4%) of rs7270101 (C). The overall Hb0 was 14.8 g/dl (14.6-14.9) [mean (95%CI); females 13.7 (13.5-13.9); males 15.5; 15.3-15.6; p<0.001]. The overall HbΔ4 was greater in major allele homozygotes [2.8 g/dl (2.6-3.0)] than in minor allele carriers [1.6 (1.4-1.9); p<0.001]. Irrespective of the ITPA genotypes HbΔ4 was smaller in female [2.0 (1.7-2.2)] than in male patients [2.6 (2.4-2.8); p<0.001] and among females in premenopausal [1.5 (1.3-1.8)] than in postmenopausal patients [2.7 (2.3-3.1); p<0.001]. CONCLUSIONS: Irrespective of the protective effect of ITPA mutations, premenopausal females less likely develop ribavirin induced anemia.


Assuntos
Anemia/induzido quimicamente , Hepatite C Crônica/tratamento farmacológico , Polimorfismo de Nucleotídeo Único/genética , Pirofosfatases/genética , Ribavirina/efeitos adversos , Ribavirina/uso terapêutico , Fatores Sexuais , Adulto , Alelos , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Genótipo , Homozigoto , Humanos , Interferon-alfa/uso terapêutico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Pré-Menopausa/fisiologia , Proteínas Recombinantes/uso terapêutico
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