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1.
Front Cell Dev Biol ; 10: 1052098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467415

RESUMO

The incidence of new cancer cases is expected to increase significantly in the future, posing a worldwide problem. In this regard, precision oncology and its diagnostic tools are essential for developing personalized cancer treatments. Digital pathology (DP) is a particularly key strategy to study the interactions of tumor cells and the tumor microenvironment (TME), which play a crucial role in tumor initiation, progression and metastasis. The purpose of this study was to integrate data on the digital patterns of reticulin fiber scaffolding and the immune cell infiltrate, transcriptomic and epigenetic profiles in aggressive uterine adenocarcinoma (uADC), uterine leiomyosarcoma (uLMS) and their respective lung metastases, with the aim of obtaining key TME biomarkers that can help improve metastatic prediction and shed light on potential therapeutic targets. Automatized algorithms were used to analyze reticulin fiber architecture and immune infiltration in colocalized regions of interest (ROIs) of 133 invasive tumor front (ITF), 89 tumor niches and 70 target tissues in a total of six paired samples of uADC and nine of uLMS. Microdissected tissue from the ITF was employed for transcriptomic and epigenetic studies in primary and metastatic tumors. Reticulin fiber scaffolding was characterized by a large and loose reticular fiber network in uADC, while dense bundles were found in uLMS. Notably, more similarities between reticulin fibers were observed in paired uLMS then paired uADCs. Transcriptomic and multiplex immunofluorescence-based immune profiling showed a higher abundance of T and B cells in primary tumor and in metastatic uADC than uLMS. Moreover, the epigenetic signature of paired samples in uADCs showed more differences than paired samples in uLMS. Some epigenetic variation was also found between the ITF of metastatic uADC and uLMS. Altogether, our data suggest a correlation between morphological and molecular changes at the ITF and the degree of aggressiveness. The use of DP tools for characterizing reticulin scaffolding and immune cell infiltration at the ITF in paired samples together with information provided by omics analyses in a large cohort will hopefully help validate novel biomarkers of tumor aggressiveness, develop new drugs and improve patient quality of life in a much more efficient way.

2.
J Pathol ; 258(4): 426-436, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36169332

RESUMO

Endometrial tumors show substantial heterogeneity in their immune microenvironment. This heterogeneity could be used to improve the accuracy of current outcome prediction tools. We assessed the immune microenvironment of 235 patients diagnosed with low-grade, early-stage endometrial cancer. Multiplex quantitative immunofluorescence was carried out to measure CD8, CD68, FOXP3, PD-1, and PD-L1 markers, as well as cytokeratin (CK), on tissue microarrays. Clustering results revealed five robust immune response patterns, each associated with specific immune populations, cell phenotypes, and cell spatial clustering. Most samples (69%) belonged to the immune-desert subtype, characterized by low immune cell densities. Tumor-infiltrating lymphocyte (TIL)-rich samples (4%) displayed high CD8+ T-cell infiltration, as well as a high percentage of CD8/PD-1+ cells. Immune-exclusion samples (19%) displayed the lowest CD8+ infiltration combined with high PD-L1 expression levels in CK+ tumor cells. In addition, they demonstrated high tumor cell spatial clustering as well as increased spatial proximity of CD8+ /PD-1+ and CK/PD-L1+ cells. FOXP3 and macrophage-rich phenotypes (3% and 4% of total samples) displayed relatively high levels of FOXP3+ regulatory T-cells and CD68+ macrophages, respectively. These phenotypes correlated with clinical outcomes, with immune-exclusion tumors showing an association with tumor relapse. When compared with prediction models built using routine pathological variables, models optimized with immune variables showed increased outcome prediction capacity (AUC = 0.89 versus 0.78) and stratification potential. The improved prediction capacity was independent of mismatch repair protein status and adjuvant radiotherapy treatment. Further, immunofluorescence results could be partially recapitulated using single-marker immunohistochemistry (IHC) performed on whole tissue sections. TIL-rich tumors demonstrated increased CD8+ T-cells by IHC, while immune-exclusion tumors displayed a lack of CD8+ T-cells and frequent expression of PD-L1 in tumor cells. Our results demonstrate the capability of the immune microenvironment to improve standard prediction tools in low-grade, early-stage endometrial carcinomas. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Antígeno B7-H1 , Neoplasias do Endométrio , Humanos , Feminino , Linfócitos T CD8-Positivos , Receptor de Morte Celular Programada 1/metabolismo , Recidiva Local de Neoplasia/patologia , Linfócitos do Interstício Tumoral , Microambiente Tumoral , Prognóstico , Neoplasias do Endométrio/patologia , Fatores de Transcrição Forkhead/metabolismo , Biomarcadores Tumorais/metabolismo
3.
Chest ; 162(5): 1006-1016, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35714708

RESUMO

BACKGROUND: Excessive inflammation is pathogenic in the pneumonitis associated with severe COVID-19. Neutrophils are among the most abundantly present leukocytes in the inflammatory infiltrates and may form neutrophil extracellular traps (NETs) under the local influence of cytokines. NETs constitute a defense mechanism against bacteria, but have also been shown to mediate tissue damage in a number of diseases. RESEARCH QUESTION: Could NETs and their tissue-damaging properties inherent to neutrophil-associated functions play a role in the respiratory failure seen in patients with severe COVID-19, and how does this relate to the SARS-CoV-2 viral loads, IL-8 (CXCL8) chemokine expression, and cytotoxic T-lymphocyte infiltrates? STUDY DESIGN AND METHODS: Sixteen lung biopsy samples obtained immediately after death were analyzed methodically as exploratory and validation cohorts. NETs were analyzed quantitatively by multiplexed immunofluorescence and were correlated with local levels of IL-8 messenger RNA (mRNA) and the density of CD8+ T-cell infiltration. SARS-CoV-2 presence in tissue was quantified by reverse-transcriptase polymerase chain reaction and immunohistochemistry analysis. RESULTS: NETs were found in the lung interstitium and surrounding the bronchiolar epithelium with interindividual and spatial heterogeneity. NET density did not correlate with SARS-CoV-2 tissue viral load. NETs were associated with local IL-8 mRNA levels. NETs were also detected in pulmonary thrombi and in only one of eight liver tissues. NET focal presence correlated negatively with CD8+ T-cell infiltration in the lungs. INTERPRETATION: Abundant neutrophils undergoing NETosis are found in the lungs of patients with fatal COVID-19, but no correlation was found with viral loads. The strong association between NETs and IL-8 points to this chemokine as a potentially causative factor. The function of cytotoxic T-lymphocytes in the immune responses against SARS-CoV-2 may be interfered with by the presence of NETs.


Assuntos
COVID-19 , Armadilhas Extracelulares , Humanos , Armadilhas Extracelulares/fisiologia , SARS-CoV-2 , Linfócitos T Citotóxicos , Interleucina-8 , Pulmão , Neutrófilos/patologia , RNA Mensageiro/metabolismo
4.
Front Cell Dev Biol ; 9: 670185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34150764

RESUMO

The invasive tumor front (the tumor-host interface) is vitally important in malignant cell progression and metastasis. Tumor cell interactions with resident and infiltrating host cells and with the surrounding extracellular matrix and secreted factors ultimately determine the fate of the tumor. Herein we focus on the invasive tumor front, making an in-depth characterization of reticular fiber scaffolding, infiltrating immune cells, gene expression, and epigenetic profiles of classified aggressive primary uterine adenocarcinomas (24 patients) and leiomyosarcomas (11 patients). Sections of formalin-fixed samples before and after microdissection were scanned and studied. Reticular fiber architecture and immune cell infiltration were analyzed by automatized algorithms in colocalized regions of interest. Despite morphometric resemblance between reticular fibers and high presence of macrophages, we found some variance in other immune cell populations and distinctive gene expression and cell adhesion-related methylation signatures. Although no evident overall differences in immune response were detected at the gene expression and methylation level, impaired antimicrobial humoral response might be involved in uterine leiomyosarcoma spread. Similarities found at the invasive tumor front of uterine adenocarcinomas and leiomyosarcomas could facilitate the use of common biomarkers and therapies. Furthermore, molecular and architectural characterization of the invasive front of uterine malignancies may provide additional prognostic information beyond established prognostic factors.

5.
Br J Cancer ; 124(6): 1138-1149, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33402737

RESUMO

BACKGROUND: Adoptive immunotherapy with tumour-infiltrating lymphocytes (TIL) may benefit from the use of selective markers, such as PD-1, for tumour-specific T-cell enrichment, and the identification of predictive factors that help identify those patients capable of rendering tumour-reactive TILs. We have investigated this in ovarian cancer (OC) patients as candidates for TIL therapy implementation. METHODS: PD-1- and PD-1+ CD8 TILs were isolated from ovarian tumours and expanded cells were tested against autologous tumour cells. Baseline tumour samples were examined using flow cytometry, multiplexed immunofluorescence and Nanostring technology, for gene expression analyses, as well as a next-generation sequencing gene panel, for tumour mutational burden (TMB) calculation. RESULTS: Tumour-reactive TILs were detected in half of patients and were exclusively present in cells derived from the PD-1+ fraction. Importantly, a high TIL density in the fresh tumour, the presence of CD137+ cells within the PD-1+CD8+ TIL subset and their location in the tumour epithelium, together with a baseline T-cell-inflamed genetic signature and/or a high TMB, are features that identify patients rendering tumour-reactive TIL products. CONCLUSION: We have demonstrated that PD-1 identifies ovarian tumour-specific CD8 TILs and has uncovered predictive factors that identify OC patients who are likely to render tumour-specific cells from PD-1+ TILs.


Assuntos
Biomarcadores Tumorais/genética , Linfócitos T CD8-Positivos/imunologia , Regulação Neoplásica da Expressão Gênica , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Ovarianas/patologia , Receptor de Morte Celular Programada 1/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Seguimentos , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Fenótipo , Prognóstico , Estudos Retrospectivos
6.
Cancers (Basel) ; 12(11)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126649

RESUMO

The use of PD-1/PD-L1 checkpoint inhibitors in advanced NSCLC is associated with longer survival. However, many patients do not benefit from PD-1/PD-L1 blockade, largely because of immunosuppression. New immunotherapy-based combinations are under investigation in an attempt to improve outcomes. Id1 (inhibitor of differentiation 1) is involved in immunosuppression. In this study, we explored the potential synergistic effect of the combination of Id1 inhibition and pharmacological PD-L1 blockade in three different syngeneic murine KRAS-mutant lung adenocarcinoma models. TCGA analysis demonstrated a negative and statistically significant correlation between PD-L1 and Id1 expression levels. This observation was confirmed in vitro in human and murine KRAS-driven lung cancer cell lines. In vivo experiments in KRAS-mutant syngeneic and metastatic murine lung adenocarcinoma models showed that the combined blockade targeting Id1 and PD-1 was more effective than each treatment alone in terms of tumor growth impairment and overall survival improvement. Mechanistically, multiplex quantification of CD3+/CD4+/CD8+ T cells and flow cytometry analysis showed that combined therapy favors tumor infiltration by CD8+ T cells, whilst in vivo CD8+ T cell depletion led to tumor growth restoration. Co-culture assays using CD8+ cells and tumor cells showed that T cells present a higher antitumor effect when tumor cells lack Id1 expression. These findings highlight that Id1 blockade may contribute to a significant immune enhancement of antitumor efficacy of PD-1 inhibitors by increasing PD-L1 expression and harnessing tumor infiltration of CD8+ T lymphocytes.

7.
Opt Express ; 28(20): 28924-28941, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114801

RESUMO

We investigate the coherence of plasma-based soft X-ray laser (XRL) for different conditions that can alter the electron density in the gain region. We first measure the source temporal coherence in amplified spontaneous emission (ASE) mode. We develop a data analysis procedure to extract both its spectral width and pulse duration. These findings are in agreement with the spectral line shape simulations and seeded operation experimental results. Utilizing the deduced spectral width and pulse duration in a one-dimensional Bloch-Maxwell code, we reproduce the experimental temporal coherence properties of the seeded-XRL. Finally, we demonstrate efficient lasing in ASE and seeded mode at an electron density two times higher than the routine conditions. In this regime, using Bloch-Maxwell modeling, we predict the pulse duration of the seeded XRL to be ∼500fs.

8.
Mod Pathol ; 33(12): 2507-2519, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32591586

RESUMO

The precise nature of the local immune responses in lung tuberculosis (TB) granulomas requires a comprehensive understanding of their environmental complexities. At its most basic level, a granuloma is a compact, organized immune aggregate of macrophages surrounded by myeloid, B and T cells. We established two complementary multiplex immunolabeling panels to simultaneously evaluate the myeloid and lymphocytic contexture of 14 human lung TB granulomas in formalin-fixed paraffin-embedded tissue samples. We observed diverse CD3+ and CD8+ T-cell and CD20+ B lymphocyte compositions of the granuloma immune environment and a relatively homogeneous distribution of all myeloid cells. We also found significant associations between CD8+ T-cell densities and the myeloid marker CD11b and phagocytic cell marker CD68. In addition, significantly more CD68+ macrophages and CD8+ T cells were found in Mycobacterium tuberculosis-infected granulomas, as detected by Ziehl-Neelsen staining. FOXP3 expression was predominately found in a small subset of CD4+ T cells in different granulomas. As the success or failure of each granuloma is determined by the immune response within that granuloma at a local and not a systemic level, we attempted to identify the presence of reactive T cells based on expression of the T-cell activation marker CD137 (4-1BB) and programmed cell death-1 (PD-1). Only a small fraction of the CD4+ and CD8+ T cells expressed PD-1. CD137 expression was found only in a very small fraction of the CD4+ T cells in two granulomas. Our results also showed that multinucleated giant cells showed strong PD-L1 but not CTLA-4 membrane staining. This study offers new insights into the heterogeneity of immune cell infiltration in lung TB granulomas, suggesting that each TB granuloma represents a unique immune environment that might be independently influenced by the local adaptive immune response, bacterial state, and overall host disease status.


Assuntos
Imunidade Adaptativa , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Microambiente Celular/imunologia , Imunofluorescência , Granuloma/imunologia , Imunofenotipagem , Pulmão/imunologia , Mycobacterium tuberculosis/imunologia , Células Mieloides/imunologia , Tuberculose Pulmonar/imunologia , Adulto , Idoso , Biomarcadores/análise , Granuloma/microbiologia , Interações Hospedeiro-Patógeno , Humanos , Pulmão/microbiologia , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Fenótipo , Tuberculose Pulmonar/microbiologia , Adulto Jovem
9.
J Occup Environ Med ; 61(9): 729-734, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31274675

RESUMO

OBJECTIVE: Our aim was to measure the association of burnout syndrome with insulin resistance in the context of a workplace health intervention. METHODS: One-year intervention program (2015 to 2016) within a university workplace. Participants (n=55) were categorized by the presence or absence of burnout syndrome at baseline using the Maslach Burnout Inventory. Insulin resistance was calculated by the triglyceride glucose index (TyG). The Mediterranean Diet adherence score and several fitness tests were completed by the participants. RESULTS: Although participants with prevalent burnout syndrome at baseline improved their physical fitness and diet scores more than participants without burnout syndrome, multiple linear regression analyses showed that participants with prevalent burnout syndrome at baseline had increased TyG index compared with participants without burnout syndrome (ß=0.18; 95% CI, 0.01 to 0.34). CONCLUSION: Burnout syndrome may be associated with insulin resistance, despite improvements in diet and fitness.


Assuntos
Esgotamento Profissional/complicações , Resistência à Insulina , Adulto , Estudos Transversais , Diabetes Mellitus Tipo 2 , Feminino , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Local de Trabalho
10.
Opt Express ; 24(13): 14260-70, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27410582

RESUMO

Development of efficient soft x-ray laser plasma amplifiers adapted to seeded operation, requires a better control over amplifier transverse spatial extent, brilliance control and gain lifetime. Here it is shown that pumping the plasma amplifier with one long and two short pump pulses (1L2S) provides advantages in terms of control for the specified parameters in the case of Ni-like Ag x-ray laser. Also, significant tunability of the gain lifetime in the 1L2S pumping scheme for Ne-like Ti x-ray laser is observed. Direct harmonics seeding and chirped harmonics seeding amplification approaches may benefit from the control of the gain lifetime, in terms of better use of the pump energy and as a way to reduce the amplified spontaneous emission in x-ray lasers.

11.
Cancer Lett ; 370(2): 165-76, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26546046

RESUMO

Metastasis involves a series of changes in cancer cells that promote their escape from the primary tumor and colonization to a new organ. This process is related to the transition from an epithelial to a mesenchymal phenotype (EMT). Recently, some authors have shown that migratory cells with an EMT phenotype share properties of cancer stem cells (CSCs), which allow them to form a new tumor mass. The type II transmembrane serine protease TMPRSS4 is highly expressed in some solid tumors, promotes metastasis and confers EMT features to cancer cells. We hypothesized that TMPRSS4 could also provide CSC properties. Overexpression of TMPRSS4 reduces E-cadherin and induces N-cadherin and vimentin in A549 lung cancer cells, supporting an EMT phenotype. These changes are accompanied by enhanced migration, invasion and tumorigenicity in vivo. TMPRSS4 expression was highly increased in a panel of lung cancer cells cultured as tumorspheres (a typical assay to enrich for CSCs). H358 and H441 cells with knocked-down TMPRSS4 levels were significantly less able to form primary and secondary tumorspheres than control cells. Moreover, they showed a lower proportion of ALDH+ cells (examined by FACS analysis) and lower expression of some CSC markers than controls. A549 cells overexpressing TMPRSS4 conferred the opposite phenotype and were also more sensitive to the CSC-targeted drug salinomycin than control cells, but were more resistant to regular chemotherapeutic drugs (cisplatin, gemcitabine and 5-fluorouracil). Analysis of 70 NSCLC samples from patients revealed a very significant correlation between TMPRSS4 expression and CSC markers ALDH (p = 0.0018) and OCT4 (p = 0.0004), suggesting that TMPRSS4 is associated with a CSC phenotype in patients' tumors. These results show that TMPRSS4, in addition to inducing EMT, can also promote CSC features in lung cancer; therefore, CSC-targeting drugs could be an appropriate treatment for TMPRSS4+ tumors.


Assuntos
Aldeído Desidrogenase/análise , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Proteínas de Membrana/fisiologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Serina Endopeptidases/fisiologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Proteínas de Membrana/análise , Proteínas de Membrana/antagonistas & inibidores , Invasividade Neoplásica , Células-Tronco Neoplásicas/fisiologia , Fator 3 de Transcrição de Octâmero/análise , Proteínas Proto-Oncogênicas c-akt/fisiologia , Serina Endopeptidases/análise
12.
Opt Lett ; 39(21): 6102-5, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25361289

RESUMO

We have investigated a new scheme for laser plasma transient collisional soft x-ray lasers based on the use of an additional laser to produce the preplasma. Soft x-ray emission measurements made for different solid targets are presented and discussed. A significant enhancement of the SXRL emission as compared to double-pulse single-beam grazing incidence (DGRIP) using the same pump laser is reported for 13.9- and 32.6-nm SXRL wavelengths.

13.
Opt Lett ; 39(8): 2246-9, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24978964

RESUMO

An alternative, novel multiple pulse generation scheme was implemented directly after the optical compressor output of an x-ray pump laser. The new method uses a polarization sensitive thin film beam splitter and a half-wavelength wave plate for tuning the energy ratio in the multiple short pulses. Based on this method, an extensive study was made of the running parameters for a grazing incidence pumped silver x-ray laser (XRL) pumped with a long pulse of 145 mJ in 6 ns at 532 nm and up to 1.45 J in few picoseconds at 810 nm. Fivefold enhancement in the emission of the silver XRL was demonstrated using the new pump method.

14.
Opt Lett ; 38(20): 4011-4, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24321908

RESUMO

The wavefront of an injection-seeded soft x-ray laser beam generated by amplification of high-harmonic pulses in a λ=18.9 nm molybdenum plasma amplifier was measured by a Hartmann wavefront sensor with an accuracy of λ/32 root mean square (rms). A significant improvement in wavefront aberrations of 0.51±0.03λ rms to 0.23±0.01λ rms was observed as a function of plasma column length. The variation of wavefront characteristic as a function time delay between the injection of the seed and peak of soft x-ray amplifier pump was studied. The measurements were used to reconstruct the soft x-ray source and confirm its high peak brightness.

15.
Opt Lett ; 37(20): 4341-3, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23073456

RESUMO

To date, plasma-based soft x-ray lasers have demonstrated experimentally 1 µJ, 1 ps (1 MW) pulses. This Letter reports extensive study using time-dependant Maxwell-Bloch code of seeding millimeter scale plasmas that store more than 100 mJ in population inversion. Direct seeding of these plasmas has to overcome very strong amplified spontaneous emission (ASE) as well as prevent wake-field amplification. Below 100 nJ injected energy, seed produces pulses with picosecond duration. To overcome this limitation, a new scheme has been studied, taking advantage of a plasma preamplifier that dramatically increases the seed energy prior to entering the main plasma amplifier leading to ASE and wake-free, fully coherent 21.6 µJ, 80 fs pulses (0.27 GW).


Assuntos
Fenômenos Ópticos , Gases em Plasma , Raios X
16.
Opt Lett ; 35(4): 450-2, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20160780

RESUMO

This Letter reports on the optimization of a tabletop nickel-like molybdenum transient collisionally excited soft x-ray laser (SXRL) at 18.9 nm performed by a double-pulse single-beam grazing incidence pumping (DGRIP). This scheme allows for the first time, to our knowledge, the full control of the pump laser parameters including the pre-pulse duration optimally generating the SXRL amplifier under a grazing incidence. The single-beam geometry of the collinear double-pulse propagation guarantees the ideal overlap of the pre-pulse and main pulse from shot to shot resulting in a more efficient and highly stable SXRL output. SXRL energies up to 2.2 microJ are obtained with a total pump energy less than 1 J for several hours at a 10 Hz repetition rate without realignment under once optimized double pumping pulse parameters including energy ratio, time delay, pre-pulse and main pulse durations, and line focus width.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(5 Pt 2): 056408, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21230603

RESUMO

Plasma-based seeded soft-x-ray lasers have the potential to generate high energy and highly coherent short pulse beams. Due to their high density, plasmas created by the interaction of an intense laser with a solid target should store the highest amount of energy density among all plasma amplifiers. Our previous numerical work with a two-dimensional (2D) adaptive mesh refinement hydrodynamic code demonstrated that careful tailoring of plasma shapes leads to a dramatic enhancement of both soft-x-ray laser output energy and pumping efficiency. Benchmarking of our 2D hydrodynamic code in previous experiments demonstrated a high level of confidence, allowing us to perform a full study with the aim of the way for 10-100 µJ seeded soft-x-ray lasers. In this paper, we describe in detail the mechanisms that drive the hydrodynamics of plasma columns. We observed transitions between narrow plasmas, where very strong bidimensional flow prevents them from storing energy, to large plasmas that store a high amount of energy. Millimeter-sized plasmas are outstanding amplifiers, but they have the limitation of transverse lasing. In this paper, we provide a preliminary solution to this problem.


Assuntos
Hidrodinâmica , Lasers , Gases em Plasma , Elétrons , Modelos Teóricos , Raios X
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