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1.
J Biol Chem ; 295(27): 9223-9243, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32414843

RESUMO

Skp1, a subunit of E3 Skp1/Cullin-1/F-box protein ubiquitin ligases, is modified by a prolyl hydroxylase that mediates O2 regulation of the social amoeba Dictyostelium and the parasite Toxoplasma gondii The full effect of hydroxylation requires modification of the hydroxyproline by a pentasaccharide that, in Dictyostelium, influences Skp1 structure to favor assembly of Skp1/F-box protein subcomplexes. In Toxoplasma, the presence of a contrasting penultimate sugar assembled by a different glycosyltransferase enables testing of the conformational control model. To define the final sugar and its linkage, here we identified the glycosyltransferase that completes the glycan and found that it is closely related to glycogenin, an enzyme that may prime glycogen synthesis in yeast and animals. However, the Toxoplasma enzyme catalyzes formation of a Galα1,3Glcα linkage rather than the Glcα1,4Glcα linkage formed by glycogenin. Kinetic and crystallographic experiments showed that the glycosyltransferase Gat1 is specific for Skp1 in Toxoplasma and also in another protist, the crop pathogen Pythium ultimum The fifth sugar is important for glycan function as indicated by the slow-growth phenotype of gat1Δ parasites. Computational analyses indicated that, despite the sequence difference, the Toxoplasma glycan still assumes an ordered conformation that controls Skp1 structure and revealed the importance of nonpolar packing interactions of the fifth sugar. The substitution of glycosyltransferases in Toxoplasma and Pythium by an unrelated bifunctional enzyme that assembles a distinct but structurally compatible glycan in Dictyostelium is a remarkable case of convergent evolution, which emphasizes the importance of the terminal α-galactose and establishes the phylogenetic breadth of Skp1 glycoregulation.


Assuntos
Galactose/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Dictyostelium/metabolismo , Proteínas F-Box/metabolismo , Glucosiltransferases/metabolismo , Glicoproteínas/metabolismo , Glicosilação , Glicosiltransferases/metabolismo , Hidroxilação , Hidroxiprolina/metabolismo , Filogenia , Pró-Colágeno-Prolina Dioxigenase/genética , Prolil Hidroxilases/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Proteínas Ligases SKP Culina F-Box/fisiologia , Toxoplasma/metabolismo
2.
Epidemiol Infect ; 146(4): 450-457, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29397049

RESUMO

An outbreak of enterohaemorrhagic Escherichia coli O157 occurred in multiple prefectures of Japan in November 2009. We conducted two case-control studies with trace-back and trace-forward investigations to determine the source. The case definition was met by 21 individuals; 14 (66.7%) were hospitalised, but no haemolytic uraemic syndrome, acute encephalopathy or deaths occurred. Median age was 23 (range 12-48) years and 14 cases were male (66.7%). No significant associations with food were found in a case-control study by local public health centres, but our matched case-control study using Internet surveys found that beef hanging tender (or hanger steak), derived from the diaphragm of the cattle, was significantly associated with illness (odds ratio = 15.77; 95% confidence interval, 2.00-124.11). Pulsed-field gel electrophoresis analysis of isolates from patients and the suspected food showed five different patterns: two in faecal and food samples, and another three in patient faecal samples only, although there were epidemiological links to the meat consumed at the restaurants. Trace-back investigation implicated a common food processing company from outside Japan. Examination of the logistics of the meat processing company suggested that contamination did not occur in Japan. We concluded that the source of the outbreak was imported hanging tender. This investigation revealed that Internet surveys could be useful for outbreak investigations.


Assuntos
Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/isolamento & purificação , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Internet , Carne Vermelha/microbiologia , Adolescente , Adulto , Animais , Estudos de Casos e Controles , Criança , Eletroforese em Gel de Campo Pulsado , Fezes/microbiologia , Feminino , Manipulação de Alimentos , Microbiologia de Alimentos , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Restaurantes
3.
J Immunol ; 192(7): 3011-20, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24574498

RESUMO

Autoantibodies to dsDNA, produced by autoreactive plasma cells (PCs), are a hallmark of systemic lupus erythematosus and play a key role in disease pathogenesis. Recent data suggest that autoreactive PCs accumulate not only in lymphoid tissues, but also in the inflamed kidney in lupus nephritis. We hypothesized that the variable efficacy of anti-CD20 (rituximab)-mediated B cell depletion in systemic lupus erythematosus may be related to the absence of an effect on autoreactive PCs in the kidney. In this article, we report that an enrichment of autoreactive dsDNA Ab-secreting cells (ASCs) in the kidney of lupus-prone mice (up to 40% of the ASCs) coincided with a progressive increase in splenic germinal centers and PCs, and an increase in renal expression for PC survival factors (BAFF, a proliferation-inducing ligand, and IL-6) and PC attracting chemokines (CXCL12). Short-term treatment with anti-CD20 (4 wk) neither decreased anti-dsDNA nor IgG ASCs in different anatomical locations. However, long-term treatment (12 wk) significantly reduced both IgG- and dsDNA-specific ASCs. In addition, long-term treatment substantially decreased splenic germinal center and PC generation, and unexpectedly reduced the expression for PC survival factors in the kidney. These results suggest that prolonged B cell depletion may alter the PC survival niche in the kidney, regulating the accumulation and maintenance of autoreactive PCs.


Assuntos
Autoanticorpos/imunologia , Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Plasmócitos/imunologia , Animais , Anticorpos Antinucleares/imunologia , Anticorpos Antinucleares/metabolismo , Anticorpos Monoclonais Murinos/farmacologia , Antirreumáticos/farmacologia , Autoanticorpos/metabolismo , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Fator Ativador de Células B/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Sobrevivência Celular/imunologia , Quimiocina CXCL12/genética , Quimiocina CXCL12/imunologia , Quimiocina CXCL12/metabolismo , Feminino , Citometria de Fluxo , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Interleucina-6/genética , Interleucina-6/imunologia , Interleucina-6/metabolismo , Rim/imunologia , Rim/metabolismo , Rim/patologia , Lúpus Eritematoso Sistêmico/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NZB , Camundongos Endogâmicos , Microscopia de Fluorescência , Plasmócitos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rituximab , Baço/imunologia , Baço/metabolismo , Fatores de Tempo
4.
ESMO Open ; 9(4): 102981, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613908

RESUMO

BACKGROUND: Comprehensive genome profiling (CGP) serves as a guide for suitable genomically matched therapies for patients with cancer. However, little is known about the impact of the timing and types of cancer on the therapeutic benefit of CGP. MATERIALS AND METHODS: A single hospital-based pan-cancer prospective study (TOP-GEAR; UMIN000011141) was conducted to examine the benefit of CGP with respect to the timing and types of cancer. Patients with advanced solid tumors (>30 types) who either progressed with or without standard treatments were genotyped using a single CGP test. The subjects were followed up for a median duration of 590 days to examine therapeutic response, using progression-free survival (PFS), PFS ratio, and factors associated with therapeutic response. RESULTS: Among the 507 patients, 62 (12.2%) received matched therapies with an overall response rate (ORR) of 32.3%. The PFS ratios (≥1.3) were observed in 46.3% (19/41) of the evaluated patients. The proportion of subjects receiving such therapies in the rare cancer cohort was lower than that in the non-rare cancer cohort (9.6% and 17.4%, respectively; P = 0.010). However, ORR of the rare cancer patients was higher than that in the non-rare cancer cohort (43.8% and 20.0%, respectively; P = 0.046). Moreover, ORR of matched therapies in the first or second line after receiving the CGP test was higher than that in the third or later lines (62.5% and 21.7%, respectively; P = 0.003). Rare cancer and early-line treatment were significantly and independently associated with ORR of matched therapies in multivariable analysis (P = 0.017 and 0.004, respectively). CONCLUSION: Patients with rare cancer preferentially benefited from tumor mutation profiling by increasing the chances of therapeutic response to matched therapies. Early-line treatments after profiling increase the therapeutic benefit, irrespective of tumor types.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Neoplasias/genética , Neoplasias/tratamento farmacológico , Feminino , Medicina de Precisão/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Adulto , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão , Adulto Jovem , Doenças Raras/genética , Doenças Raras/tratamento farmacológico , Genômica/métodos
5.
Arthritis Rheum ; 64(2): 493-503, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21905015

RESUMO

OBJECTIVE: To investigate the hypothesis that proteasome inhibition may have potential in the treatment of SLE, by targeting plasmacytoid dendritic cells (PDCs) and plasma cells, both of which are critical in disease pathogenesis. METHODS: Lupus-prone mice were treated with the nonselective proteasome inhibitors carfilzomib and bortezomib, the immunoproteasome inhibitor ONX 0914, or vehicle control. Tissue was harvested and analyzed by flow cytometry using standard markers. Nephritis was monitored by evaluation for proteinuria and by histologic analysis of kidneys. Serum anti-double-stranded DNA (anti-dsDNA) levels were measured by enzyme-linked immunosorbent assay (ELISA), and total IgG and dsDNA antibody-secreting cells (ASCs) by enzyme-linked immunospot assay. Human peripheral blood mononuclear cells or mouse bone marrow cells were incubated with Toll-like receptor (TLR) agonists and proteasome inhibitors, and interferon-α (IFNα) levels were measured by ELISA and flow cytometry. RESULTS: Early treatment of lupus-prone mice with the dual-targeting proteasome inhibitors carfilzomib or bortezomib or the immunoproteasome-specific inhibitor ONX 0914 prevented disease progression, and treatment of mice with established disease dramatically abrogated nephritis. Treatment had profound effects on plasma cells, with greater reductions in autoreactive than in total IgG ASCs, an effect that became more pronounced with prolonged treatment and was reflected in decreasing serum autoantibody levels. Notably, proteasome inhibition efficiently suppressed production of IFNα by TLR-activated PDCs in vitro and in vivo, an effect mediated by inhibition of both PDC survival and PDC function. CONCLUSION: Inhibition of the immunoproteasome is equally efficacious as dual targeting agents in preventing lupus disease progression by targeting 2 critical pathways in disease pathogenesis, type I IFN activation and autoantibody production by plasma cells.


Assuntos
Células Produtoras de Anticorpos/efeitos dos fármacos , Ácidos Borônicos/uso terapêutico , Interferon Tipo I/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Nefrite Lúpica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Inibidores de Proteases/uso terapêutico , Pirazinas/uso terapêutico , Animais , Células Produtoras de Anticorpos/imunologia , Autoanticorpos/imunologia , Ácidos Borônicos/farmacologia , Bortezomib , Progressão da Doença , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Nefrite Lúpica/imunologia , Camundongos , Oligopeptídeos/farmacologia , Inibidores de Proteases/farmacologia , Pirazinas/farmacologia
6.
Nat Genet ; 4(4): 361-6, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8401583

RESUMO

A variety of maps of the human genome have been constructed, including cloned DNA maps. We have isolated 40 of the 42 NotI sites that exist on the long arm of human chromosome 21, as NotI linking clones and constructed a complete NotI restriction map spanning the entire region. This map, which provides the most reliable ordering and distance estimation in the region from a pericentromeric locus to the terminus, demonstrates the usefulness of linking clone mapping for analysing human chromosomes.


Assuntos
Cromossomos Humanos Par 21 , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Mapeamento por Restrição , Animais , Clonagem Molecular , DNA/análise , DNA/genética , Ligação Genética , Marcadores Genéticos , Genoma Humano , Humanos , Células Híbridas , Camundongos
7.
Int J Oral Maxillofac Surg ; 50(11): 1413-1421, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33663900

RESUMO

The purpose of this study was to investigate the prognostic value of prognostic nutritional index (PNI) in oral squamous cell carcinoma (OSCC) patients and to undertake a comparative evaluation of the prognostic value of comparing PNI, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) in terms of prognostic utility. A retrospective study was conducted involving 203 consecutive patients with OSCC who were treated with radical surgery with curative intent. The PNI and systemic inflammatory response were developed, and their prognostic utility was evaluated. Kaplan-Meier curve analysis and log-rank testing showed that PNI (P< 0.001), NLR (P=0.011), PLR (P=0.013), and LMR (P=0.014) were significantly associated with overall survival. Multivariate analysis identified PNI as an independent prognostic factor for OSCC patients (P=0.029). In time-dependent receiver operating characteristic curve analysis, PNI was continuously superior to that of NLR, PLR, and LMR. In conclusion, this study suggested that PNI offered an independent prognostic biomarker in OSCC patients undergoing radical surgery. However, this study was small and retrospective, thus further investigations are needed to clarify the utility of PNI for tailor-made treatments in clinical settings.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/cirurgia , Humanos , Neoplasias Bucais/cirurgia , Neutrófilos , Avaliação Nutricional , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
8.
J Biol Chem ; 284(47): 32248-55, 2009 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-19801661

RESUMO

Factor VIIIa is comprised of A1, A2, and A3C1C2 subunits. Several lines of evidence have identified the A2 558-loop as interacting with factor IXa. The contributions of individual residues within this region to inter-protein affinity and cofactor activity were assessed following alanine scanning mutagenesis of residues 555-571 that border or are contained within the loop. Variants were expressed as isolated A2 domains in Sf9 cells using a baculovirus construct and purified to >90%. Two reconstitution assays were employed to determine affinity and activity parameters. The first assay reconstituted factor Xase using varying concentrations of A2 mutant and fixed levels of A1/A3C1C2 dimer purified from wild type (WT), baby hamster kidney cell-expressed factor VIII, factor IXa, and phospholipid vesicles to determine the inter-molecular K(d) for A2. The second assay determined the K(d) for A2 in factor VIIIa by reconstituting various A2 and fixed levels of A1/A3C1C2. Parameter values were determined by factor Xa generation assays. WT A2 expressed in insect cells yielded similar K(d) and k(cat) values following reconstitution as WT A2 purified from baby hamster kidney cell-expressed factor VIII. All A2 variants exhibited modest if any increases in K(d) values for factor VIIIa assembly. However, variants S558A, V559A, D560A, G563A, and I566A showed >9-fold increases in K(d) for factor Xase assembly, implicating these residues in stabilizing A2 association with factor IXa. Furthermore, variants Y555A, V559A, D560A, G563A, I566A, and D569A showed >80% reduction in k(cat) for factor Xa generation. These results identify residues in the 558-loop critical to interaction with factor IXa in Xase.


Assuntos
Fator IXa/química , Fator VIIIa/química , Alanina/química , Animais , Catálise , Linhagem Celular , Cricetinae , Dimerização , Inibidores Enzimáticos/farmacologia , Insetos , Cinética , Mutagênese , Mutação , Fenótipo , Ligação Proteica , Estrutura Terciária de Proteína
9.
J Synchrotron Radiat ; 16(Pt 3): 391-4, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19395804

RESUMO

100 ps time-resolved X-ray solution-scattering capabilities have been developed using multilayer optics at the beamline NW14A, Photon Factory Advanced Ring, KEK. X-ray pulses with an energy bandwidth of DeltaE/E = 1-5% are generated by reflecting X-ray pulses (DeltaE/E = 15%) through multilayer optics, made of W/B(4)C or depth-graded Ru/C on silicon substrate. This tailor-made wide-bandwidth X-ray pulse provides high-quality solution-scattering data for obtaining photo-induced molecular reaction dynamics. The time-resolved solution scattering of CH(2)I(2) in methanol is demonstrated as a typical example.


Assuntos
Dispositivos Ópticos , Síncrotrons/instrumentação , Difração de Raios X/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade , Raios X
10.
Tissue Cell ; 41(1): 79-84, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18722634

RESUMO

To investigate formation of the three primary germ layers in mouse embryoid bodies (EBs), we observed changes in structure and gene expression over a 7-day culture period. We compared these changes using two methods for EB formation: hanging drop (HD) and static suspension culture (SSC). Light microscopy showed that a stratified columnar epithelial layer developed on the surface of EBs formed using the HD method. From Day 3 in culture, ultrastructural changes occurred in the aligned cellular membranes. Condensation of actin filaments was followed by formation of complicated adherent junctions and dilatation of intercellular canaliculi containing well-developed microvilli. These changes were more marked in EBs formed by the HD method than the SSC method. On Day 5 of culture, Brachyury gene expression, a marker for mesoderm formation, was detected only with the HD method. Nestin, an ectoderm marker, and Foxa2, an endoderm marker, were expressed with both methods. These results suggest that in EBs formed with the HD method, actin formation and Brachyury gene expression mark the transition from two to three primary germ layers. Additionally, the HD method promotes more rapid and complete development of mouse EBs than does the SSC method. While the SSC method is simple and easy to use, it needs improvement to form more complete EBs.


Assuntos
Desenvolvimento Embrionário/genética , Células-Tronco Embrionárias/fisiologia , Células-Tronco Embrionárias/ultraestrutura , Regulação da Expressão Gênica no Desenvolvimento , Citoesqueleto de Actina/fisiologia , Citoesqueleto de Actina/ultraestrutura , Animais , Biomarcadores , Linhagem Celular , Ectoderma/embriologia , Ectoderma/fisiologia , Ectoderma/ultraestrutura , Endoderma/embriologia , Endoderma/fisiologia , Endoderma/ultraestrutura , Junções Intercelulares/fisiologia , Junções Intercelulares/ultraestrutura , Mesoderma/embriologia , Mesoderma/fisiologia , Mesoderma/ultraestrutura , Camundongos , Microscopia Eletrônica de Transmissão
11.
Int J Sports Med ; 30(6): 426-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19199215

RESUMO

To assess oxidative stress (OS) induced by endurance exercise, concentrations of serum reactive oxygen species (ROS) were determined in 70 Japanese male amateur runners completing a two-day ultra-marathon race. Serum ROS levels were analyzed at three time points: before the race (baseline), after the 1st day race (mid-race), and after the 2nd day race (goal) (post-race). The means (SE) of ROS were 151.4(3.7) (U. CARR.), 168.7(4.4), and 156.8(4.4), respectively. Significant positive trends were noted between age and serum ROS concentrations at the three race points (p<0.05 for all). After adjusting for age, BMI and average monthly running distance, the baseline serum ROS concentrations were positively associated with completion times of the first-day race, in particular (p<0.05), suggesting that the concentrations may predict physical performance. The ROS production increased at mid-race (p<0.05), but the levels returned to baseline levels at post-race, indicating that an antioxidant defense system may develop post-race to reduce OS.


Assuntos
Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/sangue , Corrida/fisiologia , Adulto , Fatores Etários , Desempenho Atlético/fisiologia , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Resistência Física/fisiologia
12.
Oncogene ; 26(8): 1201-12, 2007 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-16924232

RESUMO

Double-stranded RNA-dependent protein kinase (PKR), a ubiquitously expressed serine/threonine kinase, has been implicated in the regulation or modulation of cell growth through multiple signaling pathways, but how PKR regulates tumor necrosis factor (TNF)-induced signaling pathways is poorly understood. In the present study, we used fibroblasts derived from PKR gene-deleted mice to investigate the role of PKR in TNF-induced activation of nuclear factor-kappaB (NF-kappaB), mitogen-activated protein kinases (MAPKs) and growth modulation. We found that in wild-type mouse embryonic fibroblast (MEF), TNF induced NF-kappaB activation as measured by DNA binding but deletion of PKR abolished this activation. This inhibition was associated with suppression of inhibitory subunit of NF-kappaB (IkappaB)alpha kinase (IKK) activation, IkappaBalpha phosphorylation and degradation, p65 phosphorylation and nuclear translocation, and NF-kappaB-dependent reporter gene transcription. TNF-induced Akt activation needed for IKK activation was also abolished by deletion of PKR. NF-kappaB activation was diminished in PKR-deleted cells transfected with TNF receptor (TNFR) 1, TNFR-associated death domain and TRAF2 plasmids; NF-kappaB activated by NF-kappaB-inducing kinase, IKK or p65, however, was minimally affected. Among the MAPKs, it was interesting that whereas TNF-induced c-Jun N-terminal kinase (JNK) activation was abolished, activation of p44/p42 MAPK and p38 MAPK was potentiated in PKR-deleted cells. TNF induced the expression of NF-kappaB-regulated gene products cyclin D1, c-Myc, matrix metalloproteinase-9, survivin, X-linked inhibitor-of-apoptosis protein (IAP), IAP1, Bcl-x(L), A1/Bfl-1 and Fas-associated death domain protein-like IL-1beta-converting enzyme-inhibitory protein in wild-type MEF but not in PKR-/- cells. Similarly, TNF induced the proliferation of wild-type cells, but this proliferation was completely suppressed in PKR-deleted cells. Overall, our results indicate that PKR differentially regulates TNF signaling; IKK, Akt and JNK were positively regulated, whereas p44/p42 MAPK and p38 MAPK were negatively regulated.


Assuntos
Proliferação de Células/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , eIF-2 Quinase/fisiologia , Animais , Apoptose , Ativação Enzimática , Deleção de Genes , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Quinase I-kappa B/metabolismo , MAP Quinase Quinase 4/metabolismo , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , eIF-2 Quinase/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Oncogene ; 26(10): 1385-97, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16953224

RESUMO

Constitutively activated nuclear factor-kappaB (NF-kappaB) has been associated with a variety of aggressive tumor types, including head and neck squamous cell carcinoma (HNSCC); however, the mechanism of its activation is not fully understood. Therefore, we investigated the molecular pathway that mediates constitutive activation of NF-kappaB in a series of HNSCC cell lines. We confirmed that NF-kappaB was constitutively active in all HNSCC cell lines (FaDu, LICR-LON-HN5 and SCC4) examined as indicated by DNA binding, immunocytochemical localization of p65, by NF-kappaB-dependent reporter gene expression and its inhibition by dominant-negative (DN)-inhibitory subunit of NF-kappaB (IkappaBalpha), the natural inhibitor of NF-kappaB. Constitutive NF-kappaB activation in HNSCC was found to be due to constitutive activation of IkappaBalpha kinase (IKK); and this correlated with constitutive expression of phosphorylated forms of IkappaBalpha and p65 proteins. All HNSCC showed the expression of p50, p52, p100 and receptor-interacting protein; all linked with NF-kappaB activation. The expression of constitutively active NF-kappaB in HNSCC is mediated through the tumor necrosis factor (TNF) signaling pathway, as NF-kappaB reporter activity was inhibited by DN-TNF receptor-associated death domain (TRADD), DN-TNF receptor-associated factor (TRAF)2, DN-receptor-interacting protein (RIP), DN-transforming growth factor-beta-activated kinase 1 (TAK1), DN-kappa-Ras, DN-AKT and DN-IKK but not by DN-TRAF5 or DN-TRAF6. Constitutive NF-kappaB activation was also associated with the autocrine expression of TNF, TNF receptors and receptor-activator of NF-kappaB and its ligand in HNSCC cells but not interleukin (IL)-1beta. All HNSCC cell lines expressed IL-6, a NF-kappaB-regulated gene product. Furthermore, treatment of HNSCC cells with anti-TNF antibody downregulated constitutively active NF-kappaB, and this was associated with inhibition of IL-6 expression and cell proliferation. Our results clearly demonstrate that constitutive activation of NF-kappaB is mediated through the TRADD-TRAF2-RIP-TAK1-IKK pathway, making TNF a novel target in the treatment of head and neck cancer.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , NF-kappa B/biossíntese , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Quinase I-kappa B/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Fator de Transcrição RelA , Fatores de Crescimento Transformadores/metabolismo
14.
Neuroscience ; 153(4): 1245-55, 2008 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-18440713

RESUMO

The activation of glial cells in the CNS has been suggested to be involved in abnormal pain sensation after peripheral nerve injury. Previous studies demonstrated phosphorylation of p38 mitogen-activated protein kinase (MAPK) in spinal cord glial cells after peripheral nerve injury, and such phosphorylation has been suggested to be involved in the development of neuropathic pain. The aim of this study was to examine the dorsal column nuclei for phosphorylation of p38 MAPK following peripheral nerve injury and to explore a possibility of its contribution to neuropathic pain. Immunohistochemical labeling for phosphorylated p38 (p-p38) MAPK was performed in histological sections of the rat spinal cord and medulla oblongata after the fifth lumbar (L5) spinal nerve ligation (SNL). The number of p-p38 MAPK-immunoreactive (IR) cells was significantly increased in the L5 dorsal horn and the gracile nucleus ipsilateral to the injury at days 3-21 after SNL. Double immunofluorescence labeling with cell-specific markers revealed that p-p38 MAPK-IR cells co-expressed OX-42, suggesting their microglial identity. Increased immunofluorescence labeling for OX-42 indicated that microglial cells were activated by SNL in the L5 dorsal horn and the gracile nucleus ipsilateral to the injury. Continuous infusion of a p38 MAPK inhibitor into the cisterna magna for 14 days beginning on the day of SNL suppressed the development of tactile allodynia, but not thermal hyperalgesia induced by nerve injury. These results demonstrate that SNL activates p38 MAPK pathway in microglia in the gracile nucleus as well as in the spinal cord dorsal horn. Activation of p38 MAPK in medullary microglia may contribute to the pathogenesis of neuropathic pain.


Assuntos
Hiperestesia/etiologia , Bulbo/metabolismo , Microglia/fisiologia , Doenças do Sistema Nervoso Periférico/complicações , Doenças do Sistema Nervoso Periférico/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Comportamento Animal , Antígeno CD11b/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Proteína Glial Fibrilar Ácida/metabolismo , Hiperestesia/tratamento farmacológico , Imidazóis/administração & dosagem , Masculino , Limiar da Dor/efeitos dos fármacos , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Fosfopiruvato Hidratase/metabolismo , Piridinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Nervos Espinhais/patologia , Fatores de Tempo
15.
Brain Res ; 1226: 33-8, 2008 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-18619576

RESUMO

The trigeminal ganglion (TG) and mesencephalic trigeminal tract nucleus (Mes5) were investigated in wild type and dystonia musculorum (dt) mice to study the effect of dystonin deficiency on primary sensory neurons in the trigeminal nervous system. At postnatal day 14, the number of TG neurons was markedly decreased in dt mice when compared to wild type mice (43.1% reduction). In addition, dystonin disruption decreased the number of sensory neurons which bound to isolectin B4, and contained calcitonin gene-related peptide or high-affinity nerve growth factor receptor TrkA. Immunohistochemistry for caspase-3 demonstrated that dystonin deficiency induced excess cell death of TG neurons during the early postnatal period. In contrast, Mes5 neurons were barely affected in dt mice. These data together suggest that dystonin is necessary for survival of nociceptors but not proprioceptors in the trigeminal nervous system.


Assuntos
Proteínas do Citoesqueleto/deficiência , Proteínas do Tecido Nervoso/deficiência , Nociceptores/metabolismo , Células Receptoras Sensoriais/metabolismo , Gânglio Trigeminal/citologia , Núcleos do Trigêmeo/citologia , Animais , Proteínas de Transporte , Caspase 3/metabolismo , Distonina , Regulação da Expressão Gênica/genética , Lectinas/metabolismo , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Receptor trkA/metabolismo
16.
Clin Neurophysiol ; 119(6): 1346-52, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18396453

RESUMO

OBJECTIVE: To test if motor imagery prevents the rest-induced suppression of anterior horn cell excitability. METHODS: Ten healthy subjects underwent two separate experiments, each consisting of stimulating the median nerve 100 times and recording F-waves from abductor pollicis brevis (APB) in three consecutive sessions: (1) after muscle exercise to standardize the baseline, (2) after immobilization of APB for 3h and (3) after muscle exercise to check recovery. We instructed the subject to volitionally relax APB in experiment 1 (relaxation task), and to periodically simulate thumb abduction without actual movement in experiment 2 (imagery task). RESULTS: F-wave persistence and amplitude declined after relaxation task and recovered quickly after exercise, but changed little with imagery task. F-wave latencies showed no change when analyzed individually. The frequency distribution of collective F-waves recorded from all subjects remained the same after relaxation task, but showed a shift toward longer latencies after imagery task. CONCLUSIONS: Mental imagery without overt motor output suffices to counter the effect of sustained volitional muscle relaxation, which would, otherwise, cause a reversible reduction in anterior horn cell excitability. SIGNIFICANCE: This finding documents the importance of central drive for spinal excitability, which affects F-wave studies of a paretic muscle.


Assuntos
Células do Corno Anterior/fisiologia , Potencial Evocado Motor/fisiologia , Imagens, Psicoterapia , Movimento (Física) , Córtex Motor/fisiologia , Inibição Neural/fisiologia , Adulto , Análise de Variância , Estimulação Elétrica/métodos , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Músculo Esquelético/efeitos da radiação , Inibição Neural/efeitos da radiação , Tempo de Reação/fisiologia , Relaxamento
17.
Sarcoidosis Vasc Diffuse Lung Dis ; 25(1): 15-20, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19070256

RESUMO

BACKGROUND AND AIM OF THE WORK: The causes of sarcoidosis are still unknown. Propionibacterial subspieces are thought to be one of the most likely sources of antigens. Here we attempted to measure the amount of propionibacterial DNA in bronchoalveolar lavage (BAL) cell samples from patients with sarcoidosis and other pulmonary diseases. METHODS: We examined BAL cells from 42 patients with sarcoidosis and 30 controls. Using quantitative polymerase chain reaction (PCR) for 16S rRNA of Propionibacterium acnes (P. acnes) and Propionibacterium granulosum (P. granulosum), we measured the amount of propionibacterial DNA in 500 ng of total DNA extracted from BAL cells from patients with sarcoidosis or other lung diseases. The correlation between clinical findings and the results of quantitative PCR were analyzed. RESULTS: The mean level of P. acnes DNA from patients with sarcoidosis was 59.9 genomes per 500 ng of total DNA, which was significantly higher than that in controls (20.7 genomes, p<0.000l). The mean level of P. granulosum DNA from patients with sarcoidosis was 1.2 genomes, which was similar to that in controls (1.0 +/-1.6 genomes, p=0.52). The number of genomes of P. acnes in BAL cells was correlated with the serum angiotensin-converting enzyme (ACE) level and the percentage of macrophages in BAL fluid from patients with sarcoidosis. CONCLUSIONS: The amount of P. acnes DNA in BAL cells from patients with sarcoidosis was significantly higher than that in BAL cells from patients with other pulmonary diseases. P. acnes may be involved in the pathogenesis of sarcoidosis.


Assuntos
Líquido da Lavagem Broncoalveolar/química , DNA Bacteriano/análise , Reação em Cadeia da Polimerase/métodos , Propionibacterium acnes/genética , Sarcoidose Pulmonar/microbiologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/microbiologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Propionibacterium/genética , Propionibacterium/isolamento & purificação , Propionibacterium acnes/isolamento & purificação , Estudos Retrospectivos , Sarcoidose Pulmonar/diagnóstico
18.
J Nutr Health Aging ; 22(1): 53-58, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29300422

RESUMO

OBJECTIVES: This study aimed to examine the interrelationships among occlusal support, dysphagia, malnutrition, and activities of daily living in aged individuals needing long-term care. DESIGN: Cross-sectional study and path analysis. SETTING: Long-term health care facilities, acute care hospitals, and the community. PARTICIPANTS: Three hundred and fifty-four individuals aged ≥ 65 years with dysphagia or potential dysphagia in need of long-term care. MEASUREMENTS: The modified Eichner Index, Dysphagia Severity Scale, Mini Nutritional Assessment Short Form, and Barthel index. RESULTS: The participants included 118 males and 236 females with a mean (standard deviation) age of 83 (8) years. A total of 216 participants had functional occlusal support with or without dentures. Of the total participants, 73 were within normal limits regarding the severity of dysphagia, 119 exhibited dysphagia without aspiration, and 162 exhibited dysphagia with aspiration. Only 34 had a normal nutritional status, while 166 participants were malnourished, and 154 were at risk of malnutrition. The median Barthel index score was 30. Path analysis indicated two important findings: occlusal support had a direct effect on dysphagia (standard coefficient = 0.33), and dysphagia was associated directly with malnutrition (standard coefficient = 0.50). Dysphagia and malnutrition were associated directly with impaired activities of daily living (standard coefficient = 0.57, 0.22). CONCLUSION: In aged individuals needing long-term care, occlusal support is associated directly with dysphagia and indirectly with malnutrition and activities of daily living via dysphagia.


Assuntos
Atividades Cotidianas , Transtornos de Deglutição/epidemiologia , Dentaduras/estatística & dados numéricos , Assistência de Longa Duração/estatística & dados numéricos , Desnutrição/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Transtornos de Deglutição/complicações , Transtornos de Deglutição/fisiopatologia , Ingestão de Alimentos , Feminino , Avaliação Geriátrica/métodos , Hospitais , Humanos , Vida Independente , Pacientes Internados , Assistência de Longa Duração/métodos , Masculino , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Estado Nutricional , Ajuste Oclusal , Reprodutibilidade dos Testes , Inquéritos e Questionários
19.
J Clin Invest ; 99(7): 1645-50, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9120008

RESUMO

Heat shock protein 70 (HSP70) has been reported to be involved in the myocardial self-preservation system. To obtain the evidence that HSP70 plays a direct role in the protection from myocardial ischemia-reperfusion injury, rat hearts were transfected with human HSP70 gene by intracoronary infusion of hemagglutinating virus of Japan (HVJ)-liposome containing human HSP70 gene. The control hearts were infused with HVJ-liposome without the HSP70 gene. The hearts from whole-body heat-stressed or nontreated rats were also examined. Western blot and immunohistochemical analysis showed that apparent overexpression of HSP70 occurred in the gene transfected hearts and that gene transfection might be more effective for HSP70 induction than heat stress. In Langendorff perfusion, better functional recovery as well as less creatine phosphokinase leakage after ischemia were obtained in the gene transfected hearts with HSP70 than in the control or nontreated hearts. Furthermore, the gene transfected hearts showed better functional recovery than the heat-stressed hearts. These results indicated that overexpressed HSP70 plays a protective role in myocardial injury, suggesting the possibility that gene transfection with HSP70 may become a novel method for myocardial protection through enforcing the self-preservation systems.


Assuntos
Proteínas de Choque Térmico HSP70/fisiologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Western Blotting , Proteínas de Choque Térmico HSP70/genética , Humanos , Imuno-Histoquímica , Isquemia Miocárdica/terapia , Ratos , Ratos Sprague-Dawley , Transfecção
20.
Brain Res ; 1153: 98-102, 2007 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-17466283

RESUMO

The effect of neonatal masseteric nerve transection on primary proprioceptors was examined in the mesencephalic trigeminal tract nucleus (Mes5) of the rat. At 72 h to 21 days after the injury, the number of Mes5 neurons decreased on the side ipsilateral to the transection. The means+/-SD of percentage proportion of ipsilateral/contralateral neurons at 72 h and 21 days were 69.9+/-7.5% and 58.2+/-14.6%, respectively. The application of brain-derived neurotrophic factor to the proximal stump of the masseteric nerve delayed the loss of Mes5 neurons at 72 h after the injury; the mean numbers+/-SD of ipsilateral and contralateral Mes5 neurons in injured animals with BDNF application was 553.6+/-61.9 and 558.4+/-55.3, respectively. Saline application had no effect on the injury-induced loss of Mes5 neurons; i.e., the mean numbers+/-SD of ipsilateral and contralateral Mes5 neurons were 367.3+/-72.5 and 543+/-33.5, respectively. These findings indicate that trigeminal primary proprioceptors are sensitive to the neonatal injury. The survival of proprioceptors during early postnatal period is probably dependent upon brain-derived neurotrophic factor in the trigeminal nervous system.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Músculo Masseter/inervação , Doenças do Sistema Nervoso Periférico/patologia , Núcleos do Trigêmeo/fisiopatologia , Animais , Animais Recém-Nascidos , Axotomia/métodos , Contagem de Células/métodos , Feminino , Lateralidade Funcional , Masculino , Neurônios/metabolismo , Parvalbuminas/metabolismo , Doenças do Sistema Nervoso Periférico/etiologia , Ratos , Fatores de Tempo , Núcleos do Trigêmeo/patologia
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