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2.
Phys Rev Lett ; 120(26): 265701, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30004754

RESUMO

In this work, we monitor the onset of nonthermal melting in single-crystal silicon by implementing an x-ray pump-x-ray probe scheme. Using the ultrashort pulses provided by the Linac Coherent Light Source (SLAC) and a custom-built split-and-delay line for hard x rays, we achieve the temporal resolution needed to detect the onset of the transition. Our data show no loss of long-range order up to 150±40 fs from photoabsorption, which we interpret as the time needed for the electronic system to equilibrate at or above the critical nonthermal melting temperature. Once such equilibration is reached, the loss of long-range atomic order proceeds inertially and is completed within 315±40 fs from photoabsorption.

3.
Br J Dermatol ; 177(5): 1367-1375, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28380264

RESUMO

BACKGROUND: Plasmacytoid dendritic cells (pDCs) are a subset of dendritic cells specialized in the production of type I interferon (IFN-α/ß) and involved in various cutaneous inflammatory and autoimmune disorders, such as cutaneous lupus erythematosus (CLE) and vitiligo. Heat shock proteins (HSPs) are molecular chaperones essential for maintaining cellular functions, but they can act as a danger signal during inflammation. OBJECTIVES: To decipher the role of HSP70 in the production of IFN-α by pDCs in CLE and vitiligo. METHODS: Expression of HSP70 and CD123+ pDCs was analysed by immunohistochemistry or immunofluorescence in CLE and vitiligo skin samples. Flow cytometry was performed to analyse expression of HSP70 receptors, activation markers on pDCs and DNA uptake by pDCs in the presence of HSP70. The impact of HSP70 on DNA-induced IFN-α secretion by pDCs was evaluated by enzyme-linked immunosorbent assay (ELISA). The effect of IFN-α on chemokine (C-X-C motif) ligand 9 (CXCL9)/10 gene and protein expression by keratinocytes was determined by real-time polymerase chain reaction and ELISA. RESULTS: Infiltration of pDCs in CLE and progressive vitiligo was primarily located in the epidermis, close to keratinocytes expressing HSP70. In vitro experiments revealed that the pDCs expressing HSP70 receptor Lox-1 (lectin-like oxidized low-density lipoprotein-receptor-1) were able to aggregate HSP70. Exogenous HSP70 induced activation of pDCs and increased the uptake of exogenous DNA. Furthermore, HSP70 potentiated DNA-induced IFN-α production by pDCs. Finally, IFN-α induced expression of CXCL9 and CXCL10 by keratinocytes. CONCLUSIONS: These data demonstrate that interaction between HSP70 and pDCs in CLE and vitiligo is a prerequisite for the enhancement of IFN-α production, and could be an interesting target.


Assuntos
Células Dendríticas/metabolismo , Proteínas de Choque Térmico HSP70/fisiologia , Interferon-alfa/biossíntese , Lúpus Eritematoso Cutâneo/etiologia , Vitiligo/etiologia , Adulto , Idoso , Células Cultivadas , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Feminino , Humanos , Queratinócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Receptor Toll-Like 9/agonistas , Adulto Jovem
4.
Sci Total Environ ; 916: 169703, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38228238

RESUMO

We present a glacial-related lake inventory for a region spanning 41.5° - 47° S in Patagonian Andes, where information on past glacier lake outburst floods (GLOF's) has hitherto remained significantly underreported. Analyzing remotely sensed images, we obtained data on 702 glacial-related lakes. Through detailed geomorphic assessments and manual supervision, we revised current inventories and added 35 GLOFs triggered from moraine/bedrock dammed lakes failures. The regional GLOF inventory presented contains information on 71 historical failures of moraine/bedrock dammed glacial lakes. From this database we analyzed outburst timing and managed to constrain 37 events occurrences within a period of 1 year. Around 40 % of them have occurred since the early 2000's, most of them originating from lakes probably formed as a delayed response to the glacial retreat imposed by the end of the Little Ice Age. On the other hand, we analyzed meteorological conditions for a sub-set of 10 events constrained within a 10-days period, finding a strong link between atmospheric rivers, cut-off lows impacting the southern Andes, and GLOFs. Only one case is likely to have been triggered by a Mw 4.9 earthquake. Based on topographic potential for avalanching, we estimated GLOF hazard potential, recognizing at least 3 subregions with high hazard, which moreover can be highly susceptible to climate conditions that regionally affect GLOF occurrence.

6.
Ann Dermatol Venereol ; 140(10): 635-40, 2013 Oct.
Artigo em Francês | MEDLINE | ID: mdl-24090895

RESUMO

BACKGROUND: Large-cell transformation in mycosis fungoides [MF] is associated with an aggressive clinical course and poor survival. In addition to tumour progression, infectious complications may be the cause of death. We report a case of aseptic pustular dermatosis in transformed MF that very quickly became aggressive and was followed by rapid death of the patient. PATIENTS AND METHODS: A 47-year-old man presented with disseminated CD30+ transformed MF skin tumours refractory to chemotherapy for nine consecutive months. Ten days after a first course of dexamethasone, cytarabine and carboplatin, he was hospitalized for febrile neutropenia. Following this episode of neutropenia, he developed a febrile pustular rash disseminated on the tumours and on plaques, associated with marked neutrophilic leucocytosis. Bacteriological and mycological skin and blood samples were negative. Tumour biopsies showed a dermal infiltrate of CD30+ T-cells corresponding to the transformed MF, mixed with neutrophils. The pustule biopsies revealed intra-epidermal pustules and dermal-epidermal infiltration of neutrophils. The pustular eruption regressed with corticosteroids. Despite a last line of treatment with romidepsin, the patient died 6 weeks after the "neutrophilic" event. DISCUSSION: Episodes of neutrophilic dermatosis [ND] are frequently seen in haematological disease and some substances can induce a variant form of eccrine hidradenitis. However, our patient's presentation was different, without the appearance of "classic" ND but rather diffuse pustular lesions carrying a poor prognosis, which was followed by rapid death. Once the hypothesis of infectious complications has been ruled out, treatment is based on systemic corticosteroids associated with specific treatment of the lymphoma.


Assuntos
Micose Fungoide/complicações , Síndrome de Sweet/etiologia , Corticosteroides/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Depsipeptídeos/uso terapêutico , Progressão da Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Evolução Fatal , Neutropenia Febril/induzido quimicamente , Neutropenia Febril/complicações , Neutropenia Febril/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Micose Fungoide/tratamento farmacológico , Invasividade Neoplásica , Neutrófilos/patologia , Pancitopenia/etiologia , Polietilenoglicóis/uso terapêutico , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Síndrome de Sweet/patologia , Vincristina/administração & dosagem , Vincristina/efeitos adversos
10.
Sci Rep ; 10(1): 15024, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929148

RESUMO

Newly developed millennial δ13C larch tree-ring chronology from Siberia allows reconstruction of summer (July) vapor pressure deficit (VPD) changes in a temperature-limited environment. VPD increased recently, but does not yet exceed the maximum values reconstructed during the Medieval Warm Anomaly. The most humid conditions in the Siberian North were recorded in the Early Medieval Period and during the Little Ice Age. Increasing VPD under elevated air temperature affects the hydrology of these sensitive ecosystems by greater evapotranspiration rates. Further VPD increases will significantly affect Siberian forests most likely leading to drought and forest mortality even under additional access of thawed permafrost water. Adaptation strategies are needed for Siberian forest ecosystems to protect them in a warming world.

11.
Struct Dyn ; 7(2): 024301, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32161776

RESUMO

The conversion of light into usable chemical and mechanical energy is pivotal to several biological and chemical processes, many of which occur in solution. To understand the structure-function relationships mediating these processes, a technique with high spatial and temporal resolutions is required. Here, we report on the design and commissioning of a liquid-phase mega-electron-volt (MeV) ultrafast electron diffraction instrument for the study of structural dynamics in solution. Limitations posed by the shallow penetration depth of electrons and the resulting information loss due to multiple scattering and the technical challenge of delivering liquids to vacuum were overcome through the use of MeV electrons and a gas-accelerated thin liquid sheet jet. To demonstrate the capabilities of this instrument, the structure of water and its network were resolved up to the 3 rd hydration shell with a spatial resolution of 0.6 Å; preliminary time-resolved experiments demonstrated a temporal resolution of 200 fs.

15.
Heredity (Edinb) ; 85 Pt 5: 444-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11122422

RESUMO

The taxon Forficula auricularia L. (Dermaptera: Forficulidae) is a complex of two sibling species that differ in life history (number of clutches per year and imaginal diapause) and that have diverged at the molecular level. The study of a contact zone in the Pyrenean Mountains, using the PCR-RFLP method on two mitochondrial regions (the 16S rRNA and the Cytochrome Oxidase intergenic region), revealed the coexistence of the sibling species at intermediate altitude (1200 m) whereas at lower and higher altitudes only one species was found. An allozyme study, conducted simultaneously and based on four polymorphic loci (PGI1, AAT1, Est-P1 and Est-P2), showed no sign of nuclear introgression. The apparent lack of hybridization in the field is consistent with a postzygotic barrier observed in the laboratory (a nearly complete failure to produce F(1) hybrids). This contact zone is probably a sympatric zone between two genetically differentiated species.


Assuntos
Ortópteros/classificação , Ortópteros/genética , Polimorfismo Genético , Altitude , Animais , Cruzamentos Genéticos , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , França , Íntrons , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética
16.
J Immunol ; 167(11): 6559-67, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11714825

RESUMO

IL-17 is a proinflammatory cytokine, and its in vivo expression induces neutrophilia in mice. IL-17E is a recently described member of an emerging family of IL-17-related cytokines. IL-17E has been shown to bind IL-17Rh1, a protein distantly related to the IL-17R, suggesting that IL-17E probably possesses unique biological functions. In this study, we have identified the murine ortholog of IL-17E and developed transgenic mice to characterize its actions in vivo. Biological consequences of overexpression of murine (m)IL-17E, both unique to IL-17E and similar to IL-17, were revealed. Exposure to mIL-17E resulted in a Th2-biased response, characterized by eosinophilia, increased serum IgE and IgG1, and a Th2 cytokine profile including elevated serum levels of IL-13 and IL-5 and elevated gene expression of IL-4, IL-5, IL-10, and IL-13 was observed in many tissues. Increased gene expression of IFN-gamma in several tissues and elevated serum TNF-alpha were also noted. In addition, IL-17E induces G-CSF production in vitro and mIL-17E-transgenic mice had increased serum G-CSF and exhibit neutrophilia, a property shared by IL-17. Moreover, exposure to mIL-17E elicited pathological changes in multiple tissues, particularly liver, heart, and lungs, characterized by mixed inflammatory cell infiltration, epithelial hyperplasia, and hypertrophy. Taken together, these findings suggest that IL-17E is a unique pleiotropic cytokine and may be an important mediator of inflammatory and immune responses.


Assuntos
Quimiocinas CXC , Citocinas/biossíntese , Citocinas/genética , Transtornos do Crescimento/genética , Transtornos do Crescimento/imunologia , Peptídeos e Proteínas de Sinalização Intercelular , Interleucina-17/biossíntese , Interleucina-17/genética , Icterícia/genética , Icterícia/imunologia , Células Th2/imunologia , Células 3T3 , Sequência de Aminoácidos , Animais , Moléculas de Adesão Celular/biossíntese , Quimiocina CXCL1 , Fatores Quimiotáticos/biossíntese , Clonagem Molecular , Citocinas/isolamento & purificação , Citocinas/fisiologia , Eosinofilia/genética , Eosinofilia/imunologia , Regulação da Expressão Gênica/imunologia , Fator Estimulador de Colônias de Granulócitos/biossíntese , Substâncias de Crescimento/biossíntese , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Interleucina-13/sangue , Interleucina-17/isolamento & purificação , Interleucina-17/fisiologia , Interleucina-5/sangue , Icterícia/enzimologia , Leucocitose/genética , Leucocitose/imunologia , Fígado/enzimologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Neutrófilos/imunologia , Neutrófilos/patologia , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Ratos
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