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1.
Biol Lett ; 19(11): 20230253, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37935370

RESUMO

Animals frequently make adaptive decisions about what to prioritize when faced with multiple, competing demands simultaneously. However, the proximate mechanisms of decision-making in the face of competing demands are not well understood. We explored this question using brain transcriptomics in a classic model system: threespined sticklebacks, where males face conflict between courtship and territorial defence. We characterized the behaviour and brain gene expression profiles of males confronted by a trade-off between courtship and territorial defence by comparing them to males not confronted by this trade-off. When faced with the trade-off, males behaviourally prioritized defence over courtship, and this decision was reflected in their brain gene expression profiles. A distinct set of genes and biological processes was recruited in the brain when males faced a trade-off and these responses were largely non-overlapping across two brain regions. Combined, these results raise new questions about the interplay between the neural and molecular mechanisms involved in decision-making.


Assuntos
Smegmamorpha , Animais , Masculino , Smegmamorpha/genética , Territorialidade , Perfilação da Expressão Gênica
2.
Phys Rev Lett ; 122(3): 034801, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30735413

RESUMO

A tunable plasma-based energy dechirper has been developed at FLASHForward to remove the correlated energy spread of a 681 MeV electron bunch. Through the interaction of the bunch with wakefields excited in plasma the projected energy spread was reduced from a FWHM of 1.31% to 0.33% without reducing the stability of the incoming beam. The experimental results for variable plasma density are in good agreement with analytic predictions and three-dimensional simulations. The proof-of-principle dechirping strength of 1.8 GeV/mm/m significantly exceeds those demonstrated for competing state-of-the-art techniques and may be key to future plasma wakefield-based free-electron lasers and high energy physics facilities, where large intrinsic chirps need to be removed.

4.
Ann Oncol ; 28(1): 75-82, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27687306

RESUMO

Background: Lung adenocarcinomas (LUADs) lead to the majority of deaths attributable to lung cancer. We performed whole-exome sequencing (WES) and immune profiling analyses of a unique set of clinically annotated early-stage LUADs to better understand the pathogenesis of this disease and identify clinically relevant molecular markers. Methods: We performed WES of 108 paired stage I-III LUADs and normal lung tissues using the Illumina HiSeq 2000 platform. Ten immune markers (PD-L1, PD-1, CD3, CD4, CD8, CD45ro, CD57, CD68, FOXP3 and Granzyme B) were profiled by imaging-based immunohistochemistry (IHC) in a subset of LUADs (n = 92). Associations among mutations, immune markers and clinicopathological variables were analyzed using ANOVA and Fisher's exact test. Cox proportional hazards regression models were used for multivariate analysis of clinical outcome. Results: LUADs in this cohort exhibited an average of 243 coding mutations. We identified 28 genes with significant enrichment for mutation. SETD2-mutated LUADs exhibited relatively poor recurrence- free survival (RFS) and mutations in STK11 and ATM were associated with poor RFS among KRAS-mutant tumors. EGFR, KEAP1 and PIK3CA mutations were predictive of poor response to adjuvant therapy. Immune marker analysis revealed that LUADs in smokers and with relatively high mutation burdens exhibited increased levels of immune markers. Analysis of immunophenotypes revealed that LUADs with STK11 mutations exhibited relatively low levels of infiltrating CD4+/CD8+ T-cells indicative of a muted immune response. Tumoral PD-L1 was significantly elevated in TP53 mutant LUADs whereas PIK3CA mutant LUADs exhibited markedly down-regulated PD-L1 expression. LUADs with TP53 or KEAP1 mutations displayed relatively increased CD57 and Granzyme B levels indicative of augmented natural killer (NK) cell infiltration. Conclusion(s): Our study highlights molecular and immune phenotypes that warrant further analysis for their roles in clinical outcomes and personalized immune-based therapy of LUAD.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Adenocarcinoma/mortalidade , Adenocarcinoma de Pulmão , Biomarcadores Tumorais/análise , Análise Mutacional de DNA , Intervalo Livre de Doença , Exoma , Feminino , Seguimentos , Estudo de Associação Genômica Ampla , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Mutação , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais
5.
Ann Oncol ; 28(1): 83-89, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28177435

RESUMO

Background: Lung squamous cell carcinoma (LUSC) accounts for 20­30% of non-small cell lung cancers (NSCLCs). There are limited treatment strategies for LUSC in part due to our inadequate understanding of the molecular underpinnings of the disease. We performed whole-exome sequencing (WES) and comprehensive immune profiling of a unique set of clinically annotated early-stage LUSCs to increase our understanding of the pathobiology of this malignancy. Methods: Matched pairs of surgically resected stage I-III LUSCs and normal lung tissues (n = 108) were analyzed by WES. Immunohistochemistry and image analysis-based profiling of 10 immune markers were done on a subset of LUSCs (n = 91). Associations among mutations, immune markers and clinicopathological variables were statistically examined using analysis of variance and Fisher's exact test. Cox proportional hazards regression models were used for statistical analysis of clinical outcome. Results: This early-stage LUSC cohort displayed an average of 209 exonic mutations per tumor. Fourteen genes exhibited significant enrichment for somatic mutation: TP53, MLL2, PIK3CA, NFE2L2, CDH8, KEAP1, PTEN, ADCY8, PTPRT, CALCR, GRM8, FBXW7, RB1 and CDKN2A. Among mutated genes associated with poor recurrence-free survival, MLL2 mutations predicted poor prognosis in both TP53 mutant and wild-type LUSCs. We also found that in treated patients, FBXW7 and KEAP1 mutations were associated with poor response to adjuvant therapy, particularly in TP53-mutant tumors. Analysis of mutations with immune markers revealed that ADCY8 and PIK3CA mutations were associated with markedly decreased tumoral PD-L1 expression, LUSCs with PIK3CA mutations exhibited elevated CD45ro levels and CDKN2A-mutant tumors displayed an up-regulated immune response. Conclusion(s): Our findings pinpoint mutated genes that may impact clinical outcome as well as personalized strategies for targeted immunotherapies in early-stage LUSC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Mutação , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Estudos de Coortes , Seguimentos , Humanos , Imuno-Histoquímica , Imunofenotipagem , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Medicina de Precisão , Sequenciamento do Exoma
6.
Phys Rev Lett ; 118(21): 214801, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28598675

RESUMO

Plasma-based accelerators offer the possibility to drive future compact light sources and high-energy physics applications. Achieving good beam quality, especially a small beam energy spread, is still one of the major challenges. Here, we propose to use a periodically modulated plasma density to shape the longitudinal fields acting on an electron bunch in the linear wakefield regime. With simulations, we demonstrate an on-average flat accelerating field that maintains a small beam energy spread.

8.
BMC Oral Health ; 16(1): 93, 2016 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-27604238

RESUMO

BACKGROUND: Using photographs of occlusal surfaces instead of extracted teeth for the detection of caries can be useful in multicenter studies or education. Using a panel of observers, ICDAS scores on teeth or photographs were evaluated against the histological gold standard. The hypothesis was that both outcomes were equivalent. METHODS: Four examiners with different experience in ICDAS scored photographs of occlusal surfaces of 100 extracted teeth on a monitor using ICDAS criteria. Two of the examiners had previously scored extracted teeth prior to photography. Digital images of histological sections of the teeth were observed by all examiners and consensus scores were given for each investigation site (gold standard). Kappa statistics and Spearman correlation coefficients as well as repeated measure ANOVA were performed. ROC curves were constructed for each examiner and the areas under the ROC-curves (AUC) of both scoring techniques (extracted teeth, digital images) were compared (α = 0.05). RESULTS: Intra- and inter-rater kappa for ICDAS on teeth were 0.81-0.94 and on photographs 0.54-0.88, respectively. Correlation with histology was 0.58- 0.61 for the teeth and 0.50-0.62 for the photographs. AUC of ICDAS scores of extracted teeth (mean 0.89) were slightly higher than those for photographs (mean 0.84). However, both AUC values were not statistically significant (p = 0.38). CONCLUSION: Using photographs to assess occlusal surfaces with the ICDAS criteria was not statistically different from scoring the extracted teeth.


Assuntos
Cárie Dentária , Fotografação , Extração Dentária , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Phys Rev Lett ; 114(5): 054801, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25699448

RESUMO

The Linac Coherent Light Source has added a self-seeding capability to the soft x-ray range using a grating monochromator system. We report the demonstration of soft x-ray self-seeding with a measured resolving power of 2000-5000, wavelength stability of 10(-4), and an increase in peak brightness by a factor of 2-5 across the photon energy range of 500-1000 eV. By avoiding the need for a monochromator at the experimental station, the self-seeded beam can deliver as much as 50-fold higher brightness to users.

10.
Br J Cancer ; 110(6): 1545-51, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24481402

RESUMO

BACKGROUND: Transforming growth factor ß-induced protein (TGFBI) is a secreted protein that mediates cell anchoring to the extracellular matrix. This protein is downregulated in lung cancer, and when overexpressed, contributes to apoptotic cell death. Using a small series of stage IV non-small cell lung cancer (NSCLC) patients, we previously suggested the usefulness of TGFBI as a prognostic and predictive factor in chemotherapy-treated late-stage NSCLC. In order to validate and extend these results, we broaden the analysis and studied TGFBI expression in a large series of samples obtained from stage I-IV NSCLC patients. METHODS: TGFBI expression was assessed by immunohistochemistry in 364 completely resected primary NSCLC samples: 242 adenocarcinomas (ADCs) and 122 squamous cell carcinomas (SCCs). Kaplan-Meier curves, log-rank tests and the Cox proportional hazards model were used to analyse the association between TGFBI expression and survival. RESULTS: High TGFBI levels were associated with longer overall survival (OS, P<0.001) and progression-free survival (PFS, P<0.001) in SCC patients who received adjuvant platinium-based chemotherapy. Moreover, multivariate analysis demonstrated that high TGFBI expression is an independent predictor of better survival in patients (OS: P=0.030 and PFS: P=0.026). CONCLUSIONS: TGFBI may be useful for the identification of a subset of NSCLC who may benefit from adjuvant therapy.


Assuntos
Neoplasias Pulmonares/metabolismo , Fator de Crescimento Transformador beta1/biossíntese , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Idoso , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Quimioterapia Adjuvante , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Prognóstico , Texas/epidemiologia , Fator de Crescimento Transformador beta1/genética , Resultado do Tratamento
11.
Ann Oncol ; 25(6): 1184-92, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24669013

RESUMO

BACKGROUND: Malignant pleural mesothelioma (MPM) is a lethal neoplasm exhibiting resistance to most treatment regimens and requires effective therapeutic options. Though an effective strategy in many cancer, targeted therapy is relatively unexplored in MPM because the therapeutically important oncogenic pathways and networks in MPM are largely unknown. MATERIALS AND METHODS: We carried out gene expression microarray profiling of 53 surgically resected MPMs tumors along with paired normal tissue. We also carried out whole transcriptomic sequence (RNA-seq) analysis on eight tumor specimens. Taqman-based quantitative Reverse-transcription polymerase chain reaction (qRT-PCR), western analysis and immunohistochemistry (IHC) analysis of mitotic arrest deficient-like 1 (MAD2L1) was carried out on tissue specimens. Cell viability assays of MPM cell lines were carried out to assess sensitivity to specific small molecule inhibitors. RESULTS: Bioinformatics analysis of the microarray data followed by pathway analysis revealed that the mitotic spindle assembly checkpoint (MSAC) pathway was most significantly altered in MPM tumors with upregulation of 18 component genes, including MAD2L1 gene. We validated the microarray data for MAD2L1 expression using quantitative qRT-PCR and western blot analysis on tissue lysates. Additionally, we analyzed expression of the MAD2L1 protein by IHC using an independent tissue microarray set of 80 MPM tissue samples. Robust clustering of gene expression data revealed three novel subgroups of tumors, with unique expression profiles, and showed differential expression of MSAC pathway genes. Network analysis of the microarray data showed the cytoskeleton/spindle microtubules network was the second-most significantly affected network. We also demonstrate that a nontaxane small molecule inhibitor, epothilone B, targeting the microtubules have great efficacy in decreasing viability of 14 MPM cell lines. CONCLUSIONS: Overall, our findings show that MPM tumors have significant deregulation of the MSAC pathway and the microtubule network, it can be classified into three novel molecular subgroups of potential therapeutic importance and epothilone B is a promising therapeutic agent for MPM.


Assuntos
Neoplasias Pulmonares/genética , Pontos de Checagem da Fase M do Ciclo Celular/genética , Mesotelioma/genética , Microtúbulos/patologia , Neoplasias Pleurais/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Western Blotting , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Análise por Conglomerados , Análise Mutacional de DNA , Epotilonas/farmacologia , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Mesotelioma Maligno , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pleurais/patologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos , Transcriptoma , Moduladores de Tubulina/farmacologia
13.
Phys Rev Lett ; 111(18): 184801, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24237525

RESUMO

Modern, high-brightness electron beams such as those from plasma wakefield accelerators and free-electron laser linacs continue the drive to ever-shorter bunch durations. In low-charge operation (~20 pC), bunches shorter than 10 fs are reported at the Linac Coherent Light Source (LCLS). Though suffering from a loss of phase information, spectral diagnostics remain appealing as compact, low-cost bunch duration monitors suitable for deployment in beam dynamics studies and operations instrumentation. Progress in middle-infrared (MIR) imaging has led to the development of a single-shot, MIR prism spectrometer to characterize the corresponding LCLS coherent beam radiation power spectrum for few-femtosecond scale bunch length monitoring. In this Letter, we report on the spectrometer installation as well as the temporal reconstruction of 3 to 60 fs-long LCLS electron bunch profiles using single-shot coherent transition radiation spectra.

14.
Biomed Phys Eng Express ; 9(6)2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37591227

RESUMO

The combination of magnetic resonance (MR) imaging and linear accelerators (linacs) into MR-Linacs enables continuous MR imaging and advanced gated treatments of patients. Previously, a dose-rate transient (∼8% reduced dose rate during the initial 0.5 s of each beam) was identified for a Viewray MRIdian MR-Linac (Klavsenet al2022Radiation Measurement106759). Here, the dose-rate transient is studied in more detail at four linacs of the same type at different hospitals. The implications of dose-rate transients were examined for gated treatments. The dose-rate transients were investigated using dose-per pulse measurements with organic plastic scintillators in three experiments: (i) A gated treatment with the scintillator placed in a moving target in a dynamic phantom, (ii) a gated treatment with the same dynamic conditions but with the scintillator placed in a stationary target, and (iii) measurements in a water-equivalent material to examine beam quality deviations at a dose-per-pulse basis. Gated treatments (i) compared with non-gated treatments with a static target in the same setup showed a broadening of accumulated dose profiles due to motion (dose smearing). The linac with the largest dose-rate transient had a reduced accumulated dose of up to (3.1 ± 0.65) % in the center of the PTV due to the combined dose smearing and dose-rate transient effect. Dose-rate transients were found to vary between different machines. Two MR-Linacs showed initial dose-rate transients that could not be identified from conventional linearity tests. The source of the transients includes an initial change in photon fluence rate and an initial change in x-ray beam quality. For gated treatments, this caused a reduction of more than 1% dose delivered at the central part of the beam for the studied, cyclic-motion treatment plan. Quality assurance of this effect should be considered when gated treatment with the Viewray MRIdian is implemented clinically.


Assuntos
Fótons , Plásticos , Humanos , Frequência Cardíaca , Movimento (Física) , Imagens de Fantasmas
15.
Hippocampus ; 22(3): 516-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21254303

RESUMO

Norepinephrine (NE) has been shown to facilitate learning and memory by modulating synaptic plasticity in the hippocampus in vivo. During memory consolidation, transiently stored information is transferred from the hippocampus into the cortical mantle. This process is believed to depend on the generation of sharp wave-ripple complexes (SPW-Rs), during which previously stored information might be replayed. Here, we used rat hippocampal slices to investigate neuromodulatory effects of NE on SPW-Rs, induced by a standard long-term potentiation (LTP) protocol, in the CA3 and CA1. NE (10-50 µM) dose-dependently and reversibly suppressed the generation of SPW-Rs via activation of α1 adrenoreceptors, as indicated by the similar effects of phenylephrine (100 µM). In contrast, the unspecific ß adrenoreceptor agonist isoproterenol (2 µM) significantly increased the incidence of SPW-Rs. Furthermore, ß adrenoreceptor activation significantly facilitated induction of both LTP and SPW-Rs within the CA3 network. Suppression of SPW-Rs by NE was associated with a moderate hyperpolarization in the majority of CA3 pyramidal cells and with a reduction of presynaptic Ca(2+) uptake in the stratum radiatum. This was indicated by activity-dependent changes in [Ca(2+) ](o) and Ca(2+) fluorescence signals, by changes in the paired pulse ratio of evoked EPSPs and by analysis of the coefficient of variance. In the presence of NE, repeated high frequency stimulation (high-frequency stimulation (HFS)) failed to induce SPW-Rs, although SPW-Rs appeared following washout of NE. Together, our data indicate that the NE-mediated suppression of hippocampal SPW-Rs depends on α1 adrenoreceptor activation, while their expression and activity-dependent induction is facilitated via ß1-adrenoreceptors.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Norepinefrina/farmacologia , Células Piramidais/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Estimulação Elétrica , Feminino , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiologia , Células Piramidais/fisiologia , Ratos , Ratos Wistar , Receptores Adrenérgicos alfa 1/fisiologia
16.
Ann Oncol ; 23(1): 78-85, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21430184

RESUMO

BACKGROUND: The aim of this study is to investigate the prognostic role of phosphorylated AMP-activated protein kinase (pAMPK) in surgically resected non-small-cell lung cancer (NSCLC). METHODS: Immunohistochemical staining of pAMPK was carried out on tissue microarrays containing 463 samples obtained from patients with NSCLC and correlated with clinicopathological characteristics and survival. RESULTS: pAMPK expression levels were significantly higher in never smokers versus former smokers versus current smokers (P=0.045). A positive pAMPK expression was associated with increased overall survival (OS) and recurrence-free survival (RFS) (P=0.0009 and P=0.0007, respectively). OS and RFS were statistically superior in pAMPK-positive than in pAMPK-negative patients with adenocarcinoma (ADC; median OS: 5.6 and 4.2 years, respectively, P=0.0001; median RFS: 5.0 and 2.4 years, respectively, P=0.001), whereas they were similar in those patients with squamous cell carcinoma. Multivariate analysis confirmed that pAMPK positivity was associated with OS [hazard ratio (HR)=0.574, 95% confidence interval (CI) 0.418-0.789, P=0.0006) and RFS (HR=0.608, 95% CI 0.459-0.807, and P=0.0006), independent of clinical covariates. CONCLUSIONS: High pAMPK expression levels are associated with increased survival in patients with NSCLC, especially those with ADC. Our results support further evaluation of AMP-activated protein kinase as a potential prognostic and therapeutic target for lung cancer.


Assuntos
Proteínas Quinases Ativadas por AMP/biossíntese , Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Modelos de Riscos Proporcionais , Análise Serial de Tecidos
17.
Phys Rev Lett ; 108(3): 034801, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22400747

RESUMO

We report on the successful experimental generation of electron bunches with ramped current profiles. The technique relies on impressing nonlinear correlations in the longitudinal phase space using a superconducing radio frequency linear accelerator operating at two frequencies and a current-enhancing dispersive section. The produced ~700-MeV bunches have peak currents of the order of a kilo-Ampère. Data taken for various accelerator settings demonstrate the versatility of the method and, in particular, its ability to produce current profiles that have a quasilinear dependency on the longitudinal (temporal) coordinate. The measured bunch parameters are shown, via numerical simulations, to produce gigavolt-per-meter peak accelerating electric fields with transformer ratios larger than 2 in dielectric-lined waveguides.


Assuntos
Eletricidade , Elétrons , Aceleradores de Partículas , Simulação por Computador , Lasers , Dinâmica não Linear
18.
Ultraschall Med ; 33(5): 474-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23070933

RESUMO

PURPOSE: Ultrasound elastography by acoustic radiation force impulse imaging (ARFI) is used in adults for non invasive measurement of liver stiffness, indicating liver diseases like fibrosis. To establish ARFI in children and adolescents we determined standard values of healthy liver tissue and analysed potentially influencing factors. MATERIALS AND METHODS: 132 patients between 0 and 17 years old were measured using ARFI. None of them had any liver disease or any other disease that could affect the liver secondarily. All patients had a normal ultrasound scan, a normal BMI and normal liver function tests. The mean value of all ARFI measurements was calculated and potentially influencing factors were analysed. RESULTS: The mean value of all ARFI elastography measurements was 1.16 m/sec (SD ±â€Š0.14 m/sec). Neither age (p = 0.533) nor depth of measurement (p = 0.066) had no significant influence on ARFI values, whereas a significant effect of gender was found with lower ARFI values in females (p = 0.025), however, there was no significant interaction between age groups (before or after puberty) and gender (p = 0.276). There was an interlobar difference with lower values in the right liver lobe compared to the left (p = 0.036) and with a significantly lower variance (p < 0.001). Consistend values were measured by different examiners (p = 0.108), however, the inter examiner variance deviated significantly (p < 0.001). CONCLUSION: ARFI elastography is a reliable method to measure liver stiffness in children and adolescents. In relation to studies which analyse liver diseases, the standard value of 1.16 m/sec (±â€Š0.14 m/sec) allows a differentiation of healthy versus pathological liver tissue.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Fígado/diagnóstico por imagem , Adolescente , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Cirrose Hepática/diagnóstico por imagem , Masculino , Valor Preditivo dos Testes , Valores de Referência
19.
J Exp Med ; 190(8): 1103-14, 1999 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-10523608

RESUMO

Herpes simplex virus type 1 (HSV1), a large DNA-containing virus, is endemic in all human populations investigated. After infection of mucocutaneous surfaces, HSV1 establishes a latent infection in nerve cells. Recently, it was demonstrated that HSV1 can also infect activated T lymphocytes. However, the consequences of T cell infection for viral pathogenesis and immunity are unknown. We have observed that in contrast to the situation in human fibroblasts, in human T cell lines antigen presentation by major histocompatibility complex class I molecules is not blocked after HSV1 infection. Moreover, HSV1 infection of T cells results in rapid elimination of antiviral T cells by fratricide. To dissect the underlying molecular events, we used a transgenic mouse model of HSV1 infection to demonstrate that CD95 (Apo-1, Fas)-triggered apoptosis is essential for HSV1-induced fratricide, whereas tumor necrosis factor (TNF) also contributes to this phenomenon but to a lesser extent. By contrast, neither TRAIL (TNF-related apoptosis-inducing ligand) nor perforin were involved. Finally, we defined two mechanisms associated with HSV1-associated fratricide of antiviral T cells: (a) T cell receptor-mediated upregulation of CD95 ligand and (b) a viral "competence-to-die" signal that renders activated T lymphocytes susceptible to CD95 signaling. We propose that induction of fratricide is an important immune evasion mechanism of HSV1, helping the virus to persist in the host organism throughout its lifetime.


Assuntos
Herpesvirus Humano 1/imunologia , Ativação Linfocitária/imunologia , Linfócitos T Citotóxicos/virologia , Animais , Apoptose/imunologia , Proteínas Reguladoras de Apoptose , Proteína Ligante Fas , Citometria de Fluxo , Genes MHC Classe I/imunologia , Herpesvirus Humano 1/patogenicidade , Humanos , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Necrose Tumoral alfa/imunologia , Receptor fas/imunologia
20.
Am J Ind Med ; 53(7): 724-32, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20187010

RESUMO

BACKGROUND: Sensitivity to beryllium was investigated among workers at an aluminum smelter in Norway as a consequence of the findings in an occupational exposure survey. METHODS: Three hundred and sixty-two employees and 31 reference persons were tested for sensitization to beryllium with the beryllium lymphocyte proliferation test (BeLPT) based on specifications by the US Department of Energy in 2001. The results are reported as abnormal, borderline, or normal. RESULTS: One person (0.28%) from the aluminum smelter was found to have abnormal results in two separate blood samples and is sensitized to beryllium. Three other persons had one abnormal test that was not confirmed by a second test. One person in the reference group had one abnormal and one normal test result. No borderline samples were detected. None of the employees with one or more abnormal sample results had pot room asthma. The sensitized individual worked in a Soederberg line in 1972-1974. The beryllium concentration in the work atmosphere is estimated to have been similar as today (0.1-0.3 microg/m(3)), but work routines, etc. would cause higher total exposures. CONCLUSIONS: Only one sensitized person of 362 is in line with what is found in other studies in the aluminum industry. The low number, compared with the beryllium handling industry, may be attributable to lower work atmosphere concentrations, beryllium speciation effects, or use of respiratory protection equipment. Pot room asthma does not appear to be associated with beryllium sensitization.


Assuntos
Berílio/efeitos adversos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional , Adulto , Poluição do Ar , Alumínio , Berílio/sangue , Biomarcadores/sangue , Feminino , Humanos , Masculino , Metalurgia , Pessoa de Meia-Idade , Noruega , Doenças Profissionais/sangue
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