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2.
Phys Rev Lett ; 126(1): 015703, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480771

RESUMO

We present results from the SPring-8 Angstrom Compact free electron LAser facility, where we used a high intensity (∼10^{20} W/cm^{2}) x-ray pump x-ray probe scheme to observe changes in the ionic structure of silicon induced by x-ray heating of the electrons. By avoiding Laue spots in the scattering signal from a single crystalline sample, we observe a rapid rise in diffuse scattering and a transition to a disordered, liquidlike state with a structure significantly different from liquid silicon. The disordering occurs within 100 fs of irradiation, a timescale that agrees well with first principles simulations, and is faster than that predicted by purely inertial behavior, suggesting that both the phase change and disordered state reached are dominated by Coulomb forces. This method is capable of observing liquid scattering without masking signal from the ambient solid, allowing the liquid structure to be measured throughout and beyond the phase change.

3.
Phys Rev Lett ; 126(17): 175503, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988455

RESUMO

In situ femtosecond x-ray diffraction measurements and ab initio molecular dynamics simulations were performed to study the liquid structure of tantalum shock released from several hundred gigapascals (GPa) on the nanosecond timescale. The results show that the internal negative pressure applied to the liquid tantalum reached -5.6 (0.8) GPa, suggesting the existence of a liquid-gas mixing state due to cavitation. This is the first direct evidence to prove the classical nucleation theory which predicts that liquids with high surface tension can support GPa regime tensile stress.

4.
Clin Exp Dermatol ; 37(2): 128-31, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21883402

RESUMO

A 47-year-old-man presented with rashes on his trunk and limbs, and a diagnosis of parapsoriasis was made. Ten years later, the rashes had progressed gradually to form plaques and tumours. Gene rearrangement studies revealed monoclonality of the T-cell receptor ß-chain (TCR-Jß)1 gene, and results of flow cytometry and immunohistochemical examination confirmed a diagnosis of epidermotropic CD8+ cytotoxic T-cell lymphoma. The clinical course of the disease remained indolent for some time, but about 2 years later, neutrophilic pustules formed on the surface of the skin lesions, and tumours developed in the patient's testes. Using flow cytometry, emergence of CD7+ cells was found. The patient died the following year of respiratory failure due to brain herniation. On postmortem examination, CD8+ tumour cells were found in the brain. This case demonstrates an unusually protracted indolent phase in a patient with cutaneous aggressive epidermotropic CD8+ cytotoxic T-cell lymphoma; its transition into the aggressive phase was accompanied by emergence of CD7+ cells and formation of neutrophilic pustules.


Assuntos
Antígenos CD7/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfoma Cutâneo de Células T/patologia , Dermatopatias Vesiculobolhosas/patologia , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/imunologia , Progressão da Doença , Evolução Fatal , Humanos , Linfoma Cutâneo de Células T/imunologia , Masculino , Pessoa de Meia-Idade , Dermatopatias Vesiculobolhosas/imunologia , Neoplasias Cutâneas/imunologia
5.
Nat Commun ; 12(1): 2679, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976145

RESUMO

Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1µm) over a large field of view (>1 mm2). After the evolution of a Rayleigh-Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations.

6.
J Exp Med ; 173(6): 1441-9, 1991 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2033370

RESUMO

Mice homozygous for the gene lpr develop marked lymphadenopathy and a spectrum of autoantibodies closely resembling that of human systemic lupus erythematosus. The unusual T cell phenotype of the expanded lymphocyte population and the T-dependence of several antibodies in this strain have suggested that primary T cell abnormalities underlie the autoimmune syndrome. Using double chimeras, we now show that expression of the lpr gene in B cells is absolutely necessary for autoantibody production. Combinations of anti-Thy 1.2 + C' treated bone marrow from congenic strains of C57BL/6 mice, differing only at the immunoglobulin heavy chain (Igh) and lpr loci, were transferred into lethally irradiated B6/lpr mice. Double chimerism was documented by allotype-specific surface IgD and IgM immunofluorescence assay of peripheral blood and by allotype-specific enzyme-linked immunosorbent assay for total IgM in serum. Despite the presence of both +/+ and lpr B cells, IgM and IgG2a anti-chromatin as well as IgM anti-IgG were entirely the products of lpr B cells. Total serum IgG2a and IgG1 were also dominated by the lpr phenotype but not to the same extent. A similar experiment using B6/lpr-Igha recipients confirmed these findings. Additional experiments in which B6/lpr recipients were infused with ratios of donor bone marrow favoring B6.C20 +/+ over B6/lpr showed that even though +/+ B cells were overrepresented, autoantibodies were only of the lpr allotype. In addition, in the presence of lpr B cells, normal B cells showed little response to an exogenous, T cell-dependent antigen. The data thus indicate that lpr B cells manifest an intrinsic abnormality which is essential for autoantibody production in the lpr model.


Assuntos
Autoanticorpos/imunologia , Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Animais , Transplante de Medula Óssea , Camundongos , Camundongos Endogâmicos , Quimera por Radiação , Linfócitos T/imunologia , Trinitrobenzenos/imunologia
8.
Rev Sci Instrum ; 90(5): 053303, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31153246

RESUMO

The ion-production efficiency of a newly developed singly charged ion source (SCIS) has been investigated to discuss the possibility of it being used in an isotope separation on-line system that provides 11C ions for heavy-ion cancer therapy with simultaneous verification of the irradiation field using positron emission tomography. The SCIS uses a low-energy hollow electron beam to produce singly charged carbon ions efficiently. To deliver sufficient 11C ions to the treatment room from a limited amount of 11C molecules, which are produced from a boron compound target and proton-beam irradiation via the 11B(p,n)11C reaction, the SCIS must have high ion-production efficiency. To realize this high efficiency, the SCIS was designed using a three-dimensional particle-in-cell code in previous work. With the fabricated SCIS, we performed experiments to measure the efficiency of producing CO2 + ions from nonradioactive 12CO2 molecules and C+ ions from nonradioactive 12CH4 molecules. We found that the SCIS achieved efficiencies of εC+ =4×10-3 (0.4%) for C+ production and εCO2 + =0.107 (10.7%) for CO2 + production.


Assuntos
Radioisótopos de Carbono/uso terapêutico , Radioterapia com Íons Pesados , Neoplasias/radioterapia , Radioquímica/métodos , Desenho de Equipamento , Radioquímica/instrumentação
9.
Oncogene ; 26(38): 5626-34, 2007 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-17334388

RESUMO

c-Myc N-terminal conserved domains, MbI and MbII, are essential for c-Myc-mediated transformation and transactivation. These domains recruit the STAGA (SPT3-TAF9-GCN5-acetyltransferase) coactivator complex, but not TFTC (TATA-binding protein-free TAF-containing) to the target gene promoter. Although components of this complex are well conserved between yeast and mammals, four mammalian orthologs of yeast SPT8, SPT20, SGF11 and SGF29 remain to be identified. Here, we isolated a rat ortholog of yeast SGF29, a component of yeast SAGA (SPT-ADA-GCN5-acetyltransferase) complex. Both rat (r) SGF29 and c-myc mRNAs were overexpressed in five out of the eight tested rodent tumor cells. rSGF29 directly interacted with rADA3 and co-immunoprecipitated with two other TFTC/STAGA components, rGCN5 and rSPT3. rSGF29 was recruited to the c-Myc target gene promoters together with c-Myc, and it activated c-Myc target gene expressions. Downregulation of rSGF29 suppressed the expression of c-Myc target genes and inhibited anchorage-independent growth and tumorigenicity and lung metastasis of rat hepatoma K2 cells when injected into nude mice. These results show that rSGF29 is a novel component of TFTC/STAGA complexes and could be involved in the c-Myc-mediated malignant transformation.


Assuntos
Carcinoma Hepatocelular/patologia , Histona Acetiltransferases/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Northern Blotting , Western Blotting , Células COS , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Chlorocebus aethiops , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Histona Acetiltransferases/genética , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Camundongos , Camundongos Nus , Oligonucleotídeos Antissenso/genética , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Ativação Transcricional , Transfecção , Carga Tumoral , Técnicas do Sistema de Duplo-Híbrido
10.
Rev Sci Instrum ; 89(11): 113302, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30501292

RESUMO

A singly charged ion source (SCIS) has been designed using a newly developed three-dimensional particle-in-cell (PIC) code. The SCIS is to be used in an isotope separation on-line (ISOL) system that provides 11C ions for heavy-ion cancer therapy with simultaneous verification of the dose distribution using positron emission tomography. The SCIS uses low-energy electron beams to produce singly charged carbon ions efficiently and maintain a high vacuum in the ISOL system. Because the SCIS has to realize a production efficiency of 1% if its carbon ions are to be used in the ISOL system, a suitable design for the SCIS was investigated by using the developed PIC code to study the beam trajectories of the electrons and extracted ions. The simulation results show that hollow electron beams are produced in the designed SCIS resulting in a high effective electron current. The results also predict that the designed SCIS would realize ion-production efficiencies (IPEs) of ε SCIS ≃ 6.7% for C O 2 + production from CO2 gas and ε SCIS ≃ 0.1% for C+ production from CH4 gas. Moreover, to examine the validity of the developed code and confirm that the SCIS was able to be designed appropriately, the space-charge-limited current of the electron gun and the total IPE obtained by adding the IPEs of each ion were compared between the experiment and the simulation.

11.
Sci Rep ; 8(1): 16407, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30401885

RESUMO

High resolution X-ray imaging is crucial for many high energy density physics (HEDP) experiments. Recently developed techniques to improve resolution have, however, come at the cost of a decreased field of view. In this paper, an innovative experimental detector for X-ray imaging in the context of HEDP experiments with high spatial resolution, as well as a large field of view, is presented. The platform is based on coupling an X-ray backligther source with a Lithium Fluoride detector, characterized by its large dynamic range. A spatial resolution of 2 µm over a field of view greater than 2 mm2 is reported. The platform was benchmarked with both an X-ray free electron laser (XFEL) and an X-ray source produced by a short pulse laser. First, using a non-coherent short pulse laser-produced backlighter, reduced penumbra blurring, as a result of the large size of the X-ray source, is shown. Secondly, we demonstrate phase contrast imaging with a fully coherent monochromatic XFEL beam. Modeling of the absorption and phase contrast transmission of X-ray radiation passing through various targets is presented.

12.
J Clin Invest ; 95(2): 852-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7860769

RESUMO

The immunopathology of human T cell lymphotropic virus type 1 (HTLV-I) uveitis was addressed by using T cell clones (TCC) established from the intraocular fluid of patients with HTLV-I uveitis. Proviral DNA of HTLV-I was identified in 55 out of 94 (59%) or 13 out of 36 (36%) TCC from the ocular fluid or the peripheral blood of these patients, respectively. Most of HTLV-I-infected TCC had a CD3+ CD4+ CD8- phenotype. HTLV-I infection on TCC was confirmed by analysis of the viral mRNA, nucleotide sequence, virus-associated proteins, and virus particles. HTLV-I-infected TCC, but not HTLV-I negative TCC, constitutively produced high amounts of IL-6 (1,336 +/- 1,050 pg/ml) and TNF-alpha (289 +/- 237 pg/ml) in the absence of any stimuli. HTLV-I-infected TCC from the ocular lesion also constitutively produced high amounts of IL-1 alpha (12,699 pg/ml), IL-2 (61 pg/ml), IL-3 (428 pg/ml), IL-8 (1,268 pg/ml), IL-10 (28 pg/ml), IFN-gamma (5,095 pg/ml), and GM-CSF (2,886 pg/ml). Hydrocortisone, a drug effective in vivo for the treatment of HTLV-I uveitis, severely depressed cytokine production in vitro in most cases. In summary, the results demonstrated direct evidence of HTLV-I infection of the eye and suggest that cytokines produced by HTLV-I-infected T cells are responsible for the intraocular inflammation in patients with HTLV-I uveitis.


Assuntos
Citocinas/biossíntese , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/patologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Linfócitos T/imunologia , Uveíte/imunologia , Uveíte/patologia , Adulto , Humor Aquoso/imunologia , Sequência de Bases , Síndrome de Behçet/imunologia , Síndrome de Behçet/patologia , Síndrome de Behçet/virologia , Primers do DNA , Feminino , Expressão Gênica/efeitos dos fármacos , Genes env , Genes pX , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/ultraestrutura , Humanos , Hidrocortisona/farmacologia , Interferon gama/biossíntese , Interleucinas/biossíntese , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Viral/análise , Linfócitos T/patologia , Uveíte/virologia
13.
Mol Cell Biol ; 20(6): 1956-69, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10688643

RESUMO

To identify the intracellular signals which increase the adhesiveness of leukocyte function-associated antigen 1 (LFA-1), we established an assay system for activation-dependent adhesion through LFA-1/intercellular adhesion molecule 1 ICAM-1 using mouse lymphoid cells reconstituted with human LFA-1 and then introduced constitutively active forms of signaling molecules. We found that the phorbol myristate acetate (PMA)-responsive protein kinase C (PKC) isotypes (alpha, betaI, betaII, and delta) or phosphatidylinositol-3-OH kinase (PI 3-kinase) itself activated LFA-1 to bind ICAM-1. H-Ras and Rac activated LFA-1 in a PI 3-kinase-dependent manner, whereas Rho and R-Ras had little effect. Unexpectedly, Rap1 was demonstrated to function as the most potent activator of LFA-1. Distinct from H-Ras and Rac, Rap1 increased the adhesiveness independently of PI 3-kinase, indicating that Rap1 is a novel activation signal for the integrins. Rap1 induced changes in the conformation and affinity of LFA-1 and, interestingly, caused marked LFA-1/ICAM-1-mediated cell aggregation. Furthermore, a dominant negative form of Rap1 (Rap1N17) inhibited T-cell receptor-mediated LFA-1 activation in Jurkat T cells and LFA-1/ICAM-1-dependent cell aggregation upon differentiation of HL-60 cells into macrophages, suggesting that Rap1 is critically involved in physiological processes. These unique functions of Rap1 in controlling cellular adhesion through LFA-1 suggest a pivotal role as an immunological regulator.


Assuntos
Antígeno-1 Associado à Função Linfocitária/metabolismo , Transdução de Sinais , Proteínas rap1 de Ligação ao GTP/metabolismo , Animais , Células HL-60 , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Células Jurkat , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C/metabolismo
14.
Rev Sci Instrum ; 87(2): 02B509, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932062

RESUMO

A new singly charged ion source using electron impact ionization has been developed to realize an isotope separation on-line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive (11)C ion beams. Low-energy electron beams are used in the electron impact ion source to produce singly charged ions. Ionization efficiency was calculated in order to decide the geometric parameters of the ion source and to determine the required electron emission current for obtaining high ionization efficiency. Based on these considerations, the singly charged ion source was designed and fabricated. In testing, the fabricated ion source was found to have favorable performance as a singly charged ion source.

15.
Rev Sci Instrum ; 87(2): 02C110, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932120

RESUMO

There is a desire that a carbon-ion radiotherapy facility will produce various ion species for fundamental research. Although the present Kei2-type ion sources are dedicated for the carbon-ion production, a future ion source is expected that could provide: (1) carbon-ion production for medical use, (2) various ions with a charge-to-mass ratio of 1/3 for the existing Linac injector, and (3) low cost for modification. A prototype compact electron cyclotron resonance (ECR) ion source, named Kei3, based on the Kei series has been developed to correspond to the Kei2 type and to produce these various ions at the National Institute of Radiological Sciences (NIRS). The Kei3 has an outer diameter of 280 mm and a length of 1120 mm. The magnetic field is formed by the same permanent magnet as Kei2. The movable extraction electrode has been installed in order to optimize the beam extraction with various current densities. The gas-injection side of the vacuum chamber has enough space for an oven system. We measured dependence of microwave frequency, extraction voltage, and puller position. Charge state distributions of helium, carbon, nitrogen, oxygen, and neon were also measured.


Assuntos
Carbono , Íons , Campos Magnéticos , Radioterapia/instrumentação , Radioterapia/métodos
16.
Clin Cancer Res ; 6(12): 4663-73, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11156218

RESUMO

The objectives of the present study were to determine the safety of locoregional administration of autologous lymphocytes stimulated with autologous tumor cells and interleukin (IL) 2 in vitro and to find laboratory markers to predict either clinical toxicity or clinical response. Eleven patients with advanced (n = 4) or recurrent (n = 7) esophageal cancers received the locoregional administration of these activated lymphocytes every 2 weeks for two to nine times (mean, 5.6 times), and mean numbers of the administered cells were 0.8 x 10(9) cells per treatment. The activated lymphocytes that were pretested for their surface markers and CTL activity were endoscopically injected into primary tumor sites (n = 4) or directly injected into metastatic lymph nodes (n = 2), pleural (n = 4) or ascitic (n = 1) regions. Grade 3 hypotension, grade 2 diarrhea, and grade 1 fever were observed in 1, 1, and 6 patients, respectively, and there was no adverse effect in the remaining three patients. The clinical outcome was as follows: one, complete response (CR); three, partial response (PR); two, stable response (SR); and five, progressive disease (PD). CTL activity in the administered cells was observed in 5 of the 11 patients (1 CR, 3 PR, and 1 PD) and was not observed in the remaining 6 patients (2 SR and 4 PD). Percentages of CD16+ cells in the peripheral blood of the responder group (CR+PR) significantly increased when compared with those before treatment or with those of the nonresponder group before as well as after treatment. Because the clinical toxicity was moderate and tolerable, this new method of locoregional immunotherapy will be applicable for use in treatment of patients with advanced and recurrent esophageal cancers. Both CTL activity in the administered cells and the percentages of CD16+ cells in the peripheral blood may be useful laboratory markers for predicting of clinical response.


Assuntos
Neoplasias Esofágicas/terapia , Imunoterapia , Idoso , Biomarcadores , Células Cultivadas , Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/patologia , Humanos , Imunoterapia/efeitos adversos , Interleucina-2/uso terapêutico , Fígado/patologia , Linfonodos/imunologia , Linfonodos/metabolismo , Linfonodos/patologia , Linfócitos/imunologia , Linfócitos/metabolismo , Pessoa de Meia-Idade , Receptores de IgG/sangue , Recidiva , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas
17.
Clin Cancer Res ; 7(12): 3950-62, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11751487

RESUMO

The tumor-rejection antigen SART3 possesses two antigenic epitopes (SART3(109-118) and SART3(315-323)) capable of inducing HLA-A24-restricted and tumor-specific CTLs. To determine its safety and ability to generate antitumor immune responses, 12 patients with advanced colorectal cancer were administered s.c. vaccinations of these peptides. No severe adverse events were associated with the vaccinations. Significant levels of increased cellular immune responses to both HLA-A24+ colon cancer cells and the vaccinated peptide were observed in the postvaccination peripheral blood mononuclear cells in 7 of 11 and 7 of 10 patients tested, respectively, and the higher responses were observed in those patients vaccinated with the highest dose (3 mg/injection) of the peptides. These results encourage further development of SART3 peptide vaccine for colorectal cancer patients.


Assuntos
Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/uso terapêutico , Vacinas Anticâncer/imunologia , Neoplasias Colorretais/imunologia , Proteínas de Ligação a RNA/imunologia , Proteínas de Ligação a RNA/uso terapêutico , Adulto , Idoso , Antígenos de Neoplasias/efeitos adversos , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/uso terapêutico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Epitopos/imunologia , Feminino , Antígenos HLA-A/imunologia , Antígeno HLA-A24 , Humanos , Hipersensibilidade Imediata , Imunidade Celular , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas de Ligação a RNA/efeitos adversos , Taxa de Sobrevida , Fatores de Tempo
18.
J Leukoc Biol ; 65(6): 778-85, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10380899

RESUMO

Membrane-permeable proteasome inhibitors, lactacystin (LC) and N-acetyl-Leu-Leu-norleucinal (ALLN), but not calpain inhibitor Z-Leu-leucinal (ZLL), prevented LFA-1/ICAM-1-dependent cellular adhesion of TPA-stimulated HL-60 cells. These proteasome inhibitors affected neither the induction of monocytic differentiation nor the accompanying protein-tyrosine phosphorylation. They suppressed the increase in the avidity of LFA-1 to ICAM-1 without changing the expression of these molecules. Immunoblotting using monoclonal antibody FK-1, which reacts specifically with polyubiquitinated proteins, demonstrated that the proteasome inhibitors caused the drastic accumulation of the polyubiquitinated proteins in the membrane fraction of TPA-treated HL-60 cells. This indicates that accompanying activation of LFA-1, TPA induces the polyubiquitination of the membrane proteins, which are rapidly degraded by proteasomes. These data taken together show that proteolysis mediated by the ubiquitin-proteasome system is a prerequisite for the induction of LFA-1-dependent adhesion of HL-60 cells.


Assuntos
Cisteína Endopeptidases/fisiologia , Células HL-60/citologia , Molécula 1 de Adesão Intercelular/farmacologia , Antígeno-1 Associado à Função Linfocitária/farmacologia , Complexos Multienzimáticos/fisiologia , Ubiquitinas/fisiologia , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacologia , Adenosina Trifosfatases/antagonistas & inibidores , Afinidade de Anticorpos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Células HL-60/química , Células HL-60/efeitos dos fármacos , Humanos , Leupeptinas/farmacologia , Antígeno-1 Associado à Função Linfocitária/imunologia , Monócitos/citologia , Complexo de Endopeptidases do Proteassoma , Acetato de Tetradecanoilforbol/farmacologia , Tretinoína/farmacologia
20.
Rev Sci Instrum ; 86(12): 123303, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26724018

RESUMO

A (11)C molecular production/separation system (CMPS) has been developed as part of an isotope separation on line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive (11)C ion beams. In the ISOL system, (11)CH4 molecules will be produced by proton irradiation and separated from residual air impurities and impurities produced during the irradiation. The CMPS includes two cryogenic traps to separate specific molecules selectively from impurities by using vapor pressure differences among the molecular species. To investigate the fundamental performance of the CMPS, we performed separation experiments with non-radioactive (12)CH4 gases, which can simulate the chemical characteristics of (11)CH4 gases. We investigated the separation of CH4 molecules from impurities, which will be present as residual gases and are expected to be difficult to separate because the vapor pressure of air molecules is close to that of CH4. We determined the collection/separation efficiencies of the CMPS for various amounts of air impurities and found desirable operating conditions for the CMPS to be used as a molecular separation device in our ISOL system.


Assuntos
Radioisótopos de Carbono/química , Radioisótopos de Carbono/isolamento & purificação , Ciclotrons/instrumentação , Marcação por Isótopo/instrumentação , Geradores de Radionuclídeos/instrumentação , Refrigeração/instrumentação , Íons/síntese química , Íons/isolamento & purificação , Marcação por Isótopo/métodos , Refrigeração/métodos
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