RESUMO
DNA methylation (DNAm) plays a determining role in neural cell fate and provides a molecular link between early-life stress and neuropsychiatric disease. Preterm birth is a profound environmental stressor that is closely associated with alterations in connectivity of neural systems and long-term neuropsychiatric impairment. The aims of this study were to examine the relationship between preterm birth and DNAm, and to investigate factors that contribute to variance in DNAm. DNA was collected from preterm infants (birth<33 weeks gestation) and healthy controls (birth>37 weeks), and a genome-wide analysis of DNAm was performed; diffusion magnetic resonance imaging (dMRI) data were acquired from the preterm group. The major fasciculi were segmented, and fractional anisotropy, mean diffusivity and tract shape were calculated. Principal components (PC) analysis was used to investigate the contribution of MRI features and clinical variables to variance in DNAm. Differential methylation was found within 25 gene bodies and 58 promoters of protein-coding genes in preterm infants compared with controls; 10 of these have neural functions. Differences detected in the array were validated with pyrosequencing. Ninety-five percent of the variance in DNAm in preterm infants was explained by 23 PCs; corticospinal tract shape associated with 6th PC, and gender and early nutritional exposure associated with the 7th PC. Preterm birth is associated with alterations in the methylome at sites that influence neural development and function. Differential methylation analysis has identified several promising candidate genes for understanding the genetic/epigenetic basis of preterm brain injury.
Assuntos
Encéfalo/fisiopatologia , Metilação de DNA/fisiologia , Imagem de Difusão por Ressonância Magnética , Epigenômica/métodos , Recém-Nascido Prematuro/fisiologia , Feminino , Humanos , Recém-Nascido , Masculino , Análise de Componente PrincipalRESUMO
Tumour necrosis factor-α (TNF) is a cytokine endowed with multiple functions, depending on the cellular and environmental context. TNF receptor engagement induces the formation of a multimolecular complex including the TNFR-associated factor TRAF2, the receptor-interaction protein kinase RIP1 and the cellular inhibitor of apoptosis cIAP1, the latter being essential for NF-κB activation. Here, we show that cIAP1 also regulates TNF-induced actin cytoskeleton reorganization through a cdc42-dependent, NF-κB-independent pathway. Deletion of cIAP1 prevents TNF-induced filopodia and cdc42 activation. The expression of cIAP1 or its E3-ubiquitin ligase-defective mutant restores the ability of cIAP1(-/-) MEFs to produce filopodia, whereas a cIAP1 mutant unable to bind TRAF2 does not. Accordingly, the silencing of TRAF2 inhibits TNF-mediated filopodia formation, whereas silencing of RIP1 does not. cIAP1 directly binds cdc42 and promotes its RhoGDIα-mediated stabilization. TNF decreases cIAP1-cdc42 interaction, suggesting that TNF-induced recruitment of cIAP1/TRAF2 to the receptor releases cdc42, which in turn triggers actin remodeling. cIAP1 also regulates cdc42 activation in response to EGF and HRas-V12 expression. A downregulation of cIAP1 altered the cell polarization, the cell adhesion to endothelial cells and cell intercalation, which are cdc42-dependent processes. Finally, we demonstrated that the deletion of cIAP1 regulated the HRas-V12-mediated transformation process, including anchorage-dependent cell growth, tumour growth in a xenograft model and the development of experimental metastasis in the lung.
Assuntos
Citoesqueleto de Actina/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Pseudópodes/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Animais , Western Blotting , Adesão Celular/fisiologia , Polaridade Celular/fisiologia , Modelos Animais de Doenças , Imunofluorescência , Células HEK293 , Xenoenxertos , Humanos , Imunoprecipitação , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Células NIH 3T3 , Invasividade Neoplásica/patologia , Transdução de Sinais/fisiologia , Ressonância de Plasmônio de Superfície , TransfecçãoRESUMO
Members of the inhibitor of apoptosis protein (IAP) family have demonstrated functions in cell death, cell signalling, cell migration and mitosis. Several of them are E3 enzymes in the ubiquitination of proteins that leads to their degradation by the proteosomal machinery. We previously reported that one of them, cellular inhibitor of apoptosis protein-1 (c-IAP1), migrated from the nucleus to the surface of the Golgi apparatus in cells undergoing differentiation. Here, we show that c-IAP1 is a client protein of the stress protein HSP90 beta. In three distinct cellular models, the two proteins interact and migrate from the nucleus to the cytoplasm along the differentiation process through a leptomycin B-sensitive pathway. Inhibition of HSP90 proteins by small chemical molecules and specific depletion of HSP90 beta isoform by siRNA both lead to auto-ubiquitination of c-IAP1 and its degradation by the proteasome machinery. This chaperone function of HSP90 towards c-IAP1 is specific of its beta isoform as specific depletion of HSP90alpha does not affect c-IAP1 content. Chemical inhibition of HSP90 or siRNA-mediated depletion of HSP90 beta both inhibit cell differentiation, which can be reproduced by siRNA-mediated depletion of c-IAP1. Altogether, these results suggest that HSP90 beta prevents auto-ubiquitination and degradation of its client protein c-IAP1, whose depletion would be sufficient to inhibit cell differentiation.
Assuntos
Diferenciação Celular/fisiologia , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Isoformas de Proteínas/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Proteínas de Choque Térmico HSP90/genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Macrófagos/citologia , Macrófagos/fisiologia , Isoformas de Proteínas/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismoRESUMO
Members of the inhibitor of apoptosis protein (IAP) family have demonstrated functions in cell death, cell signalling, cell migration and mitosis. Several of them are E3 enzymes in the ubiquitination of proteins that leads to their degradation by the proteosomal machinery. We previously reported that one of them, cellular inhibitor of apoptosis protein-1 (c-IAP1), migrated from the nucleus to the surface of the Golgi apparatus in cells undergoing differentiation. Here, we show that c-IAP1 is a client protein of the stress protein HSP90ß. In three distinct cellular models, the two proteins interact and migrate from the nucleus to the cytoplasm along the differentiation process through a leptomycin B-sensitive pathway. Inhibition of HSP90 proteins by small chemical molecules and specific depletion of HSP90ß isoform by siRNA both lead to auto-ubiquitination of c-IAP1 and its degradation by the proteasome machinery. This chaperone function of HSP90 towards c-IAP1 is specific of its ß isoform as specific depletion of HSP90α does not affect c-IAP1 content. Chemical inhibition of HSP90 or siRNA-mediated depletion of HSP90ß both inhibit cell differentiation, which can be reproduced by siRNA-mediated depletion of c-IAP1. Altogether, these results suggest that HSP90ß prevents auto-ubiquitination and degradation of its client protein c-IAP1, whose depletion would be sufficient to inhibit cell differentiation.Cell Death and Differentiation advance online publication, 1 February 2008; doi:10.1038/sj.cdd.4402320.
RESUMO
Trauma-induced hematomas of the limbs usually resorb without sequelae. In certain circumstances which are not fully understood, the hematoma may expand progressively, eventually leading to the development of a tumor-like mass in the soft tissues. We report the case of a chronic expanding hematoma observed in the right soleus muscle of a 75-year-old man. The mass grew +9 cm compared with the other side over a period of two to three years with no notion of recent trauma. Surgical biopsy disclosed a thick capsule containing "chocolate pus". Pathology and cytology examination led to the diagnosis of pseudo-tumor calcinosis subsequent to a hematoma which the patient had developed 34 years earlier when as a mountain guide he had experienced a tear of the soleus muscle. Local care required complete resection of the soleus muscle. The patient was able to resume activities without pain. Well described in the literature, encapsulated hematoma of the limbs is not well known in France. This case illustrated the potentially long latency period (34 years in our patient). Pathologically similar to tumor calcinosis, chronic expanding hematoma should be entertained as a possible diagnosis in a patient with a longstanding mass and a history of past trauma. The differential diagnosis with sarcoma is established by magnetic resonance imaging which reveals a peripheral low intensity signal on T1 and T2 sequences.
Assuntos
Hematoma/diagnóstico , Músculo Esquelético , Doenças Musculares/diagnóstico , Idoso , Doença Crônica , Progressão da Doença , Humanos , Perna (Membro) , Masculino , Fatores de TempoRESUMO
Solid phase adsorption of headspace vapours was used to trap occluded solvent residues contained in 41 heroin and 54 cocaine samples, seized in Switzerland between 1994 and 1996, onto activated charcoal. The residues were eluted with carbon disulphide and analysed by GC-FID. Identification was confirmed by GC-MS. The detection limits between 2-15 ppm were determined empirically on a w/w basis for 250-300 mg powder samples. Twelve and 16 solvents were identified in the heroin and cocaine samples respectively. It was possible to relate cocaine samples to each other, but heroin comparisons proved more problematical. Trends and geographic variation in solvent use are considered and recommendations are made with respect to the control of certain solvents frequently encountered in heroin and cocaine samples.
Assuntos
Cocaína , Resíduos de Drogas/análise , Heroína , Solventes/análise , Cromatografia Gasosa , Contaminação de MedicamentosRESUMO
The immunogenicity and safety of a combined diphtheria, tetanus, pertussis and Haemophilus influenzae type b-tetanus conjugate vaccine (DTP-PRP-T) was compared to the same combination obtained by the reconstitution of H. influenzae type b-tetanus conjugate vaccine lyophilized (PRP-T) with liquid diphtheria-tetanus-pertussis vaccine (DTP). Two hundred and sixty-two healthy infants were randomized to receive a intramuscular injection of 0.5 ml of one of the above combination vaccines at 2, 4 and 6 months of age, and a subgroup of 134 infants received a booster dose at 12 months. Serum antibody levels to each vaccine component were measured at ages 2, 6, 7, 12 and 13 months. Systemic and local reactions were assessed during the first 3 days after each injection by diary cards distributed to the parents. After the third dose and booster administered at 12 months of age, significant equivalence between the groups was observed, and the geometric mean titer of anti H. influenzae type b capsular polysaccharide (Hib-CP) antibodies were 5.9 and 32.6 micrograms ml-1 for the liquid combination group and 5.8 and 19.4 for the lyophilized group, respectively. After the third dose, anti-Hib-PC antibody levels of > or = 1.0 microgram ml-1 and 0.15 microgram ml-1 were seen in 94% and 100%, respectively, of the liquid combination group and 90 and 99%, respectively of the lyophilized group. After the booster dose, levels of > or = 1.0 microgram ml-1 were observed in 100% and 93.5% of the liquid combination group and the lyophilized combination group, respectively. Systemic and local reactions to the vaccination were generally mild and did not differ significantly between the groups. We conclude that the liquid combination of DTP-PRP-T is safe and at least as immunogenic as the lyophilized preparation. This liquid preparation, like other combined vaccines may be helpful for planning vaccination programs with a reduced number of injections.
Assuntos
Vacina contra Difteria, Tétano e Coqueluche/efeitos adversos , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Vacinas Anti-Haemophilus/efeitos adversos , Vacinas Anti-Haemophilus/imunologia , Toxoide Tetânico/efeitos adversos , Toxoide Tetânico/imunologia , Anticorpos Antibacterianos/biossíntese , Feminino , Liofilização , Humanos , Lactente , Masculino , Cloreto de Sódio/imunologia , Vacinas Conjugadas/efeitos adversos , Vacinas Conjugadas/imunologiaRESUMO
Aggressive fibromatosis of the breast is an uncommon benign disease. The clinical and X-Ray findings can simulate breast cancer. The diagnosis relies on histology. The typical feature of this disease is a locally aggressive but non metastasizing lesion with high recurrence rate. Treatment consists in wide excision. The role of radiation and drug therapy including antiestrogens has not been clearly established. Colonoscopy is indicated to research for an association with Gardner syndrome.
Assuntos
Neoplasias da Mama/diagnóstico , Fibromatose Agressiva/diagnóstico , Adulto , Biópsia , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Feminino , Fibromatose Agressiva/complicações , Fibromatose Agressiva/cirurgia , Síndrome de Gardner/complicações , Humanos , Mamografia , Pessoa de Meia-Idade , Fatores de Risco , Ultrassonografia MamáriaRESUMO
Expression of p35 from the DNA genome of Autographa californica nuclear polyhedrosis virus (AcMNPV) suppresses virus-induced apoptosis and promotes virus replication in Spodoptera frugiperda (SF21) cells. To examine the molecular mechanism by which p35 prevents apoptosis in insects, SF21 cells were stably transfected with p35. Neomycin-resistant cell lines that synthesized protein P35 were identified. Stable transfection with p35 protected SF21 cells from apoptosis induced by actinomycin D concentrations that caused apoptotic death of untransfected cells. Cellular expression of p35 also blocked apoptosis induced by infection with p35 null mutants and restored mutant replication to levels comparable to those of wild-type virus. In contrast, stable expression of the mammalian death suppressor bcl-2 failed to block actinomycin D- or AcMNPV-induced apoptosis. Thus, p35 was sufficient to prevent apoptosis, whereas bcl-2 was not, suggesting that the activities of the two nonhomologous death regulators are functionally distinct. Stable expression of the truncation mutant p35(1-76), containing the N terminus of p35, failed to block apoptosis. However, p35(1-76) interfered with p35 antiapoptotic activity, since stably transfected cells underwent apoptosis upon infection with wild-type AcMNPV. Despite normal levels of viral p35 transcription, P35 levels were selectively reduced during infection. Thus, p35(1-76) acted as a dominant inhibitor by directly or indirectly affecting the synthesis or stability of viral P35. These results suggested that the N terminus of P35 constitutes a functional domain which is required to interact with other proteins, possibly host invertebrate death regulators or P35 itself.
Assuntos
Apoptose , Nucleopoliedrovírus/genética , Transfecção , Proteínas Virais/biossíntese , Animais , Linhagem Celular , DNA/efeitos dos fármacos , DNA/isolamento & purificação , DNA/metabolismo , Dactinomicina/farmacologia , Teste de Complementação Genética , Immunoblotting , Proteínas Inibidoras de Apoptose , Cinética , Fases de Leitura Aberta , Fragmentos de Peptídeos/metabolismo , Plasmídeos , Proteínas Tirosina Quinases/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2 , RNA Viral/biossíntese , RNA Viral/isolamento & purificação , Mapeamento por Restrição , Spodoptera , beta-Galactosidase/biossínteseRESUMO
A high-performance affinity column containing immobilized modified GM1 (lyso-GM1) was used to study the binding of an endogenous human brain lectin (HBL) in comparison with other carbohydrate-binding proteins. The proteins are previously converted into biotinylated derivatives. Detection of biotinylated proteins in the eluates by a microtitre plate assay ensures good sensitivity. The maximum binding capacity of the adsorbent for HBL is obtained in Tris buffer supplemented with beta-mercaptoethanol. The binding is inhibitable by specific sugar. It is concluded that the use of immobilized glycolipids in analytical high-performance liquid affinity chromatographic methods may serve as models in the study of interactions between gangliosides and carbohydrate-binding proteins.
Assuntos
Gangliosídeos/química , Lectinas/química , Biotina/química , Química Encefálica , Toxina da Cólera/química , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Gangliosídeo G(M1)/química , Humanos , Lectinas de Plantas , Plantas/químicaRESUMO
In our report we describe an atypically sited thyroglossal cyst in a 67-year-old woman. The intrahyoid location is explained by one of the theories of the migration of the rudimentary thyroid during embryogenesis. The diagnosis was confirmed by CT.
Assuntos
Osso Hioide/diagnóstico por imagem , Cisto Tireoglosso/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Recidiva Local de NeoplasiaAssuntos
Instabilidade Articular/cirurgia , Traumatismos do Joelho/complicações , Ligamentos Articulares/lesões , Feminino , Seguimentos , Instabilidade Articular/etiologia , Articulação do Joelho/fisiologia , Ligamentos Articulares/cirurgia , Masculino , Movimento , Osteotomia/métodos , Ruptura , Tíbia/cirurgiaRESUMO
In the first experiment two groups (B and D) each of ten, 15-day-old chicks were fed for 33 days a diet supplemented with nosiheptide (20 g/t) and 2 groups (A and C) of 10 each a diet without medication. Groups A and B were inoculated with Salmonella typhimurium, var. copenhagen (variant resistant to nalidixic acid of the strain DVR 101) 5 days after treatment was started. At intervals of 2, 4, 6, 8, 10, 12, 14, 21, and 28 days postinoculation the following data were collected: the number of salmonella excreted per gram of feces, their duration and prevalence of excretion, and the proportion of salmonella resistant to 9 antibacterial agents commonly used in human and veterinary medicine, as well as their degree and spectrum of resistance. In the second experiment two groups of 10 chicks each were fed either a basal diet (control group) or a diet supplemented with nosiheptide at 20 g/t (treated group). Immediately before and at the end of treatment, the proportions of fecal coliforms, particularly E. coli, which were resistant to 11 commonly used antibacterial agents, and their degree and spectrum of resistance were determined in the 2 groups of chicks. All the strains isolated before treatment started were E. coli sensitive to the 11 antibacterial agents. The strains isolated at the end of treatment were coliforms otherthan E. coli (40% in the control group, 32% in the treated group) and E. coli (60 and 68%, respectively). Coliforms other than E. coli were, as is usual, resistant to ampicillin and sensitive to the other antibacterial agents. The E. coli strains were either sensitive to all the antibacterial agents or resistant to tetracycline and furazolidone (51.8% in the control group, 34.1% in the treated group), or resistant to furazolidone alone (3.7% in the control group, 5.8% in the treated group). In both experiments these determinations showed no appreciable differences between treated and untreated chicks.
Assuntos
Antibacterianos/farmacologia , Galinhas/microbiologia , Escherichia coli/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Ração Animal , Animais , Galinhas/metabolismo , Resistência Microbiana a Medicamentos , Fezes/microbiologia , Doenças das Aves Domésticas/microbiologia , Infecções por Salmonella/microbiologia , Salmonelose Animal , Tiazóis/farmacologiaRESUMO
Emericid is a new polyether polycyclic ionophore antibiotic excreted by Streptomyces hygroscopicus (DS 24 367). Active in vitro against Gram-positive bacteria, it is ineffective in vivo. At a 0.006-0.02% level in the diet it protects chickens and rabbits against coccidiosis.