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1.
World Neurosurg ; 181: 6-12, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37806520

RESUMO

BACKGROUND: Thirty years have passed since Kambin's first clinical series of lumbar disc herniations (LDH) treated by arthroscopic microdiscectomy. Despite several advances in this interim, sequestrated LDHs over the dorsal aspect of the dura, and high-grade up- or downward disc migration have been a relative limitation of the transforaminal endoscopic technique. The interlaminar window was the next step to deal with such highly migrated LDHs. Favorable outcomes were obtained in 70-90% of the patients in the long-term, but recurrence rates remained high (approximately 12%), and the approach could be limited by the size of the interlaminar window. Few relevant studies have addressed the role of translaminar full endoscopic technique for migrated LDHs. To describe an innovative modification of the translaminar full endoscopic approach with Tom Shidi needles. METHODS: This technical modification is presented in a detailed fashion for treating these challenging LDHs and illustrated through a clinical case. RESULTS: The patient underwent successful translaminar full endoscopic technique with complete pain resolution postoperatively. The postprocedural course was uneventful. A follow-up imaging showed no evidence of residual LDHs fragments. CONCLUSIONS: Translaminar full endoscopic technique with Tom Shidi needles is a promising modification of the previously presented interlaminar and translaminar endoscopic routes in the treatment of migrated LDHs to fasten surgical procedures and increase the safety of spinal canal manipulation.


Assuntos
Discotomia Percutânea , Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Discotomia Percutânea/métodos , Resultado do Tratamento , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Endoscopia/métodos , Estudos Retrospectivos
2.
Arch Microbiol ; 192(11): 883-92, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20717649

RESUMO

The fungus Phanerochaete flavido-alba is highly efficient in the oxidation of olive oil wastewater-derived polyphenols. This capability is largely due to the action of a multicopper-oxidase (MCO), encoded by the pfaL gene. We describe the sequence and organization of pfaL gene and the biochemical characterization and predicted 3D structural model of the encoded protein. pfaL gene organization and peptide sequence are highly similar to those of P. chrysosporium MCOs. However, PfaL is the first MCO in the Phanerochaete genus to show evident laccase activity. Phylogenetic analysis places PfaL in a differentiated sub-branch of ferroxidases. Protein structure analysis reveals close similarity of PfaL and ferroxidases and provides clues about the differences of activity between both types of enzymes. To summarize, P. flavido-alba laccase is the first enzyme in the novel and biochemically poorly defined group of "ferroxidases/laccases" that shows efficacious oxidation of laccase substrates, biotechnologically exploitable in bioremediation approaches.


Assuntos
Ceruloplasmina/metabolismo , Proteínas Fúngicas/metabolismo , Lacase/metabolismo , Oxirredutases/genética , Phanerochaete/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Biodegradação Ambiental , Ceruloplasmina/genética , Clonagem Molecular , Flavonoides/metabolismo , Proteínas Fúngicas/genética , Lacase/genética , Modelos Moleculares , Dados de Sequência Molecular , Phanerochaete/genética , Fenóis/metabolismo , Filogenia , Polifenóis , Alinhamento de Sequência , Especificidade por Substrato
3.
Methods Mol Biol ; 612: 97-126, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20033637

RESUMO

Although NK cells were originally identified as "naturally" active cells believed to follow a cell-autonomous activation program, it is now widely accepted that NK cells need to interact with dendritic cells for their full functional activation and for their homeostasis. In this chapter, we will provide an experimental guide to the analysis of NK cell/DC interactions in vitro and in vivo. We have put special emphasis on the recently developed mouse models allowing the inducible and specific ablation of various subsets of DCs and other myeloid cells.


Assuntos
Comunicação Celular , Células Dendríticas/citologia , Células Matadoras Naturais/citologia , Animais , Biomarcadores/metabolismo , Células da Medula Óssea/citologia , Linhagem Celular , Citocinas/metabolismo , Células Dendríticas/metabolismo , Engenharia Genética , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Espaço Intracelular/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Macrófagos/citologia , Camundongos , Modelos Biológicos , Células Mieloides/metabolismo , Coloração e Rotulagem , Receptores Toll-Like/metabolismo
4.
Environ Sci Technol ; 42(2): 584-9, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18284166

RESUMO

In view of compliance with increasingly stringent environmental legislation imposed by regional, national, and supranational (e.g., European Union) authorities, innovative environmental technologies for the treatment of dye-contaminated effluents are necessary in the color industry. In this study, effluents of an industrial dye producer were subjected to distinct treatment trains following an initial qualitative characterization. The effectiveness of ozonation and a treatment using white rot fungi (WRF) and their enzymes were compared with respect to parameters such as residual color, toxicity on human cells, and genotoxicity. A combined ozonation/WRF process was also investigated. The effluent exhibited significant toxicity that was reduced by only 10% through ozonation, whereas the fungal treatment achieved a 35% reduction. A combined treatment (ozone/WRF) caused an abatement of the toxicity by more than 70%. In addition, the initial genotoxicity of the effluent was still present after the ozone treatment, while it was completely removed through the fungal treatment.


Assuntos
Corantes , Mutagênicos , Ozônio/química , Polyporaceae/metabolismo , Poluentes Químicos da Água , Animais , Células CACO-2 , Corantes/química , Corantes/metabolismo , Corantes/toxicidade , Humanos , Lacase/metabolismo , Fígado/metabolismo , Mutagênicos/química , Mutagênicos/metabolismo , Mutagênicos/toxicidade , Oxidantes/química , Ratos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos
5.
Immunity ; 26(4): 503-17, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17398124

RESUMO

Natural killer (NK) cells are important effector cells in the control of infections. The cellular and molecular signals required for NK cell activation in vivo remain poorly defined. By using a mouse model for the inducible ablation of dendritic cells (DCs), we showed that the in vivo priming of NK cell responses to viral and bacterial pathogens required the presence of CD11c(high) DCs. After peripheral Toll-like receptor (TLR) stimulation, NK cells were recruited to local lymph nodes, and their interaction with DCs resulted in the emergence of effector NK cells in the periphery. NK cell priming was dependent on the recognition of type I IFN signals by DCs and the subsequent production and trans-presentation of IL-15 by DCs to resting NK cells. CD11c(high) DC-derived IL-15 was necessary and sufficient for the priming of NK cells. Our data define a unique in vivo role of DCs for the priming of NK cells, revealing a striking and previously unappreciated homology to T lymphocytes of the adaptive immune system.


Assuntos
Apresentação de Antígeno , Apresentação Cruzada , Células Dendríticas/imunologia , Interleucina-15/imunologia , Células Matadoras Naturais/imunologia , Animais , Antígeno CD11c/análise , Células Dendríticas/química , Interferon Tipo I , Listeriose/imunologia , Linfonodos/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos , Receptores de Antígenos de Linfócitos T , Transdução de Sinais
6.
Eur J Immunol ; 33(12): 3514-22, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14635062

RESUMO

A common feature of hematopoietic activating immunoreceptors resides in their association at the cell surface with transmembrane signaling adaptors. Several adaptors, such as the CD3 molecules, FcRgamma and KARAP/DAP12, harbor intracytoplasmic immunoreceptor tyrosine-based activation motifs (ITAM) that activate Syk-family protein tyrosine kinases. In contrast, another transmembrane adaptor, DAP10, bears a YxxM motif that delivers signals by activation of lipid kinase pathways. We show here that the human signal-regulatory protein SIRPbeta1 can associate with both DAP10 and KARAP/DAP12 in a model of RBL-2H3 cell transfectants. In association with KARAP/DAP12, SIRPbeta1 complexes are capable of inducing serotonin release and tumor necrosis factor (TNF) secretion. By contrast,in the absence of KARAP/DAP12, engagement of SIRPbeta1:DAP10 complexes does not lead to detectable serotonin release or TNF secretion by RBL-2H3 transfectants. However, triggering of SIRPbeta1:DAP10 complexes co-stimulates RBL-2H3 effector function induced by sub-optimal stimulation of the endogenous FcepsilonRI complex. Therefore, we report here a cellular model in which the association of a cell surface receptor with various signaling adaptors dictates the co-stimulatory or the direct stimulatory properties of the complex.


Assuntos
Antígenos de Diferenciação , Proteínas de Membrana/fisiologia , Receptores Imunológicos/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Linhagem Celular Tumoral , Dimerização , Humanos , Mastócitos/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Ratos , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/fisiologia , Receptores de Superfície Celular , Receptores de IgG/metabolismo , Receptores KIR , Transfecção
7.
J Exp Med ; 197(4): 437-49, 2003 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-12591902

RESUMO

Activation of CD4(+) T cells is governed by interplay between stimulatory and inhibitory receptors; predominance of stimulatory signals favors autoimmune reactions. In patients with rheumatoid arthritis, expression of the critical costimulatory molecule, CD28, is frequently lost. Instead, CD4(+)CD28(null) T cells express killer immunoglobulin-like receptors (KIRs) with a preferential expression of the stimulatory receptor, CD158j. The frequency of CD4(+)CD28(null) T cells in rheumatoid arthritis (RA) correlates with the risk for more severe disease. Moreover, the KIR2DS2 gene, which encodes for CD158j, is a genetic risk factor for rheumatoid vasculitis. CD158j signals through the adaptor molecule, KARAP/DAP12, to positively regulate cytotoxic activity in NK cells. However, the majority of CD4(+)CD28(null) T cell clones lacked the expression of KARAP/DAP12. Despite the absence of KARAP/DAP12, CD158j was functional and augmented interferon-gamma production after T cell receptor stimulation. Cross-linking of CD158j resulted in selective phosphorylation of c-Jun NH(2)-terminal protein kinase (JNK) and its upstream kinase, MKK4 that led to the expression of ATF-2 and c-Jun, all in the absence of extracellular signal-regulated kinase (ERK)1/2 phosphorylation. Mutation of the lysine residue within the transmembrane domain of CD158j abolished JNK activation, suggesting that an alternate adaptor molecule was being used. CD4(+)CD28(null) T cells expressed DAP10 and inhibition of phosphatidylinositol 3-kinase, which acts downstream of DAP10, inhibited JNK activation; however, no interaction of DAP10 with CD158j could be detected. Our data suggest that CD158j in T cells functions as a costimulatory molecule through the JNK pathway independent of KARAP/DAP12 and DAP10. Costimulation by CD158j may contribute to the autoreactivity of CD4(+)CD28(null) T cells in RA.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , MAP Quinase Quinase 4 , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Receptores Imunológicos/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Sítios de Ligação , Ativação Enzimática , Humanos , Interferon gama/biossíntese , Proteínas Quinases JNK Ativadas por Mitógeno , Células Jurkat , Proteínas de Membrana/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-jun/metabolismo , Receptores de Antígenos de Linfócitos T/fisiologia , Receptores KIR , Transcrição Gênica
8.
Nat Immunol ; 3(12): 1142-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12426565

RESUMO

Optimal lymphocyte activation requires the simultaneous engagement of stimulatory and costimulatory receptors. Stimulatory immunoreceptors are usually composed of a ligand-binding transmembrane protein and noncovalently associated signal-transducing subunits. Here, we report that alternative splicing leads to two distinct NKG2D polypeptides that associate differentially with the DAP10 and KARAP (also known as DAP12) signaling subunits. We found that differential expression of these isoforms and of signaling proteins determined whether NKG2D functioned as a costimulatory receptor in the adaptive immune system (CD8+ T cells) or as both a primary recognition structure and a costimulatory receptor in the innate immune system (natural killer cells and macrophages). This strategy suggests a rationale for the multisubunit structure of stimulatory immunoreceptors.


Assuntos
Células Matadoras Naturais/imunologia , Ativação Linfocitária/imunologia , Splicing de RNA/imunologia , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Humanos , Ativação Linfocitária/genética , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Subunidades Proteicas/genética , Subunidades Proteicas/imunologia , Receptores de Células Matadoras Naturais , Transdução de Sinais/genética , Transdução de Sinais/imunologia
9.
Eur J Immunol ; 32(9): 2653-63, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12207350

RESUMO

KARAP/DAP12 is a broadly distributed transmembrane signaling polypeptide with an immunoreceptor tyrosine-based activation motif, and is non-covalently associated with a variety of activating surface receptors. We report here the characterization of transgenic mice that overexpress KARAP/DAP12 polypeptides in both myeloid and lymphoid compartments. KARAP/DAP12-transgenic mice present, in a transgene dose-dependent manner, a complex phenotype characterized by two independent and spontaneous hematological abnormalities: (i) a severe lymphopenia and (ii) a massive inflammatory syndrome associated with neutrophilia and lung infiltration by multinucleated macrophages. These myeloid abnormalities observed in KARAP/DAP12-transgenic mice indicate that KARAP/DAP12-driven signals are critically involved in inflammation, and constitute an essential target to control the resolution of inflammatory disorders based on monocytes/macrophages and neutrophils.


Assuntos
Inflamação/genética , Linfopenia/genética , Macrófagos/patologia , Neutrófilos/patologia , Receptores Imunológicos/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Medula Óssea/metabolismo , Medula Óssea/patologia , Expressão Gênica , Predisposição Genética para Doença , Hematopoese , Humanos , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Pulmão/patologia , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Linfopenia/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Choque Séptico/induzido quimicamente , Choque Séptico/imunologia , Choque Séptico/patologia , Síndrome de Emaciação/genética , Síndrome de Emaciação/patologia
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