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In May 2017 a patient attended the emergency department at a hospital in England, with a presumed allergic reaction. He was subsequently diagnosed with measles. There were seven further confirmed cases, five of whom had received two doses of MMR vaccine. This outbreak highlights the importance of not relying on vaccination status to rule out the diagnosis of measles. Epidemiological investigations of this outbreak were particularly challenging due to the highly infectious nature of the measles virus, and prevented full elucidation of either the source of this outbreak or the transmission pathways.
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Internal stresses in materials have a considerable effect on material properties including strength, fracture toughness, and fatigue resistance. The ENGIN-X beamline is an engineering science facility at ISIS optimized for the measurement of strain and stress using the atomic lattice planes as a strain gauge. Nowadays, the rapidly rising interest in the mechanical properties of engineering materials at low temperatures has been stimulated by the dynamic development of the cryogenic industry and the advanced applications of the superconductor technology. Here we present the design and discuss the test results of a new cryogenic sample environment system for neutron scattering measurements of internal stresses in engineering materials under a load of up to 100 kN and in the temperature range of 6 K to 300 K. Complete cooling of the system starting from the room temperature down to the base temperature takes around 90 min. Understanding of internal stresses in engineering materials at cryogenic temperatures is vital for the modelling and designing of cutting-edge superconducting magnets and other superconductor based applications.
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BACKGROUND: Blood-borne biomarkers for early detection of colorectal cancer (CRC) could markedly increase screening uptake. The aim of this study was to evaluate serum carcinoembryonic antigen (CEA), CYFRA21-1 and CA125 for the early detection of CRC in an asymptomatic cohort. METHODS: This nested case-control study within UKCTOCS used 381 serial serum samples from 40 women subsequently diagnosed with CRC, 20 women subsequently diagnosed with benign disease and 40 matched non-cancer controls with three to four samples per subject taken annually up to 4 years before diagnosis. CEA, CYFRA21-1 and CA125 were measured using validated assays and performance of markers evaluated for different pre-diagnosis time groups. RESULTS: CEA levels increased towards diagnosis in a third of all cases (half of late-stage cases), whereas longitudinal profiles were static in both benign and non-cancer controls. At a threshold of >5 ng ml(-1) the sensitivities for detecting CRC up to 1 and 4 years before clinical presentation were 25% and 13%, respectively, at 95% specificity. At a threshold of >2.5 ng ml(-1), sensitivities were 57.5% and 38.4%, respectively, with specificities of 81% and 83.5%. CYFRA21-1 and CA125 had no utility as screening markers and did not enhance CEA performance when used in combination. CEA gave average lead times of 17-24 months for test-positive cases. CONCLUSIONS: CEA is elevated in a significant proportion of individuals with preclinical CRC, but would not be useful alone as a screening tool. This work sets a baseline from which to develop panels of biomarkers which combine CEA for improved early detection of CRC.
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Antígenos de Neoplasias/sangre , Antígeno Ca-125/sangre , Antígeno Carcinoembrionario/sangre , Neoplasias Colorrectales/sangre , Detección Precoz del Cáncer , Queratina-19/sangre , Adulto , Anciano , Estudios de Casos y Controles , Neoplasias Colorrectales/diagnóstico , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana EdadRESUMEN
Circulating intercellular adhesion molecule-1 (ICAM-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) have been widely proposed as potential diagnostic biomarkers for pancreatic ductal adenocarcinoma (PDAC). We report on serum protein levels prior to clinical presentation of pancreatic cancer. Serum ICAM-1 and TIMP-1 were measured by ELISA in two casecontrol sets: 1) samples from patients diagnosed with pancreatic cancer (n = 40), chronic pancreatitis (n = 20), benign jaundice due to gall stones (n = 20) and healthy subjects (n = 20); 2) a preclinical set from the UK Collaborative Trial of Ovarian Cancer Screening biobank of samples collected from 27 post-menopausal women 012 months prior to diagnosis of pancreatic cancer and controls matched for date of donation and centre. Levels of ICAM-1 and TIMP-1 were significantly elevated in set 1 in PDAC patients with jaundice compared to PDAC patients without jaundice and both proteins were elevated in patients with jaundice due to gall stones. Neither protein was elevated in samples taken 012 months prior to PDAC diagnosis compared to non-cancer control samples. In conclusion, evaluation in pre-diagnosis samples discounts ICAM-1 and TIMP-1 as biomarkers for earlier diagnosis of pancreatic cancer. Failure to account for obstructive jaundice may have contributed to the previous promise of these candidate biomarkers. BIOLOGICAL SIGNIFICANCE: Pancreatic cancer is usually diagnosed when at an advanced stage which greatly limits therapeutic options. Biomarkers that could facilitate earlier diagnosis are urgently sought.
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Biomarcadores de Tumor/sangre , Carcinoma Ductal Pancreático , Molécula 1 de Adhesión Intercelular/sangre , Neoplasias Pancreáticas , Inhibidor Tisular de Metaloproteinasa-1/sangre , Adulto , Carcinoma Ductal Pancreático/sangre , Carcinoma Ductal Pancreático/diagnóstico , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/diagnósticoRESUMEN
Interleukin-6 (IL-6) is an important pro-inflammatory cytokine involved in many autoimmune and inflammatory diseases. We have shown previously that a region from -5307 to -5202 bp upstream of the IL-6 transcriptional start site is responsible for basal IL-6 gene expression, and that there were DNA-binding proteins involved from electrophoretic mobility shift assay (EMSA) and transient expression experiments. Here we have combined surface plasmon resonance technology with mass spectrometry analysis and have identified nuclear proteins bound to this region. HNRNPA1 and HNRNPA2B1 were found consistently. EMSA supershift and chromatin immunoprecipitation assays confirmed the involvement of HNRNPA1, but not of HNRNPA2B1. Knocking down the HNRNPA1 expression by small interfering RNA resulted in reduced IL-6 transcriptional activity as assessed from transfection experiments using reporter constructs, mRNA and protein measurements. Overexpression of HNRNPA1 cDNA increased IL-6 mRNA expression. This regulation was dependent on the presence of the sequence from -5307 to -5202 bp of the IL-6 gene. Thus, HNRNPA1 is a novel transcriptional regulator of IL-6 expression, acting via the 5'-flanking sequence of the gene.
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Región de Flanqueo 5' , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Interleucina-6/genética , Transcripción Genética , Regulación hacia Arriba , Células HeLa , Ribonucleoproteína Nuclear Heterogénea A1 , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/genética , Humanos , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismoAsunto(s)
Infecciones por Adenovirus Humanos/complicaciones , Trasplante de Corazón/efectos adversos , Herpes Simple/complicaciones , Trasplante de Riñón/efectos adversos , Fallo Hepático Agudo/virología , Infecciones Oportunistas/complicaciones , Adulto , Ciliopatías , Resultado Fatal , Femenino , Cardiopatías Congénitas/cirugía , Herpesvirus Humano 2 , Humanos , Inmunosupresores/efectos adversos , Enfermedades Renales Quísticas/cirugía , Amaurosis Congénita de Leber/cirugía , Masculino , Persona de Mediana Edad , Atrofias Ópticas Hereditarias/cirugíaRESUMEN
BACKGROUND: Biliary tract cancer (BTC) and benign biliary strictures can be difficult to differentiate using standard tumour markers such as serum carbohydrate antigen 19-9 (CA19-9) as they lack diagnostic accuracy. METHODS: Two-dimensional difference gel electrophoresis and tandem mass spectrometry were used to profile immunodepleted serum samples collected from cases of BTC, primary sclerosing cholangitis (PSC), immunoglobulin G4-associated cholangitis and healthy volunteers. The serum levels of one candidate protein, leucine-rich α-2-glycoprotein (LRG1), were verified in individual samples using enzyme-linked immunosorbent assay and compared with serum levels of CA19-9, bilirubin, interleukin-6 (IL-6) and other inflammatory markers. RESULTS: We report increased LRG1, CA19-9 and IL-6 levels in serum from patients with BTC compared with benign disease and healthy controls. Immunohistochemical analysis also demonstrated increased staining of LRG1 in BTC compared with cholangiocytes in benign biliary disease. The combination of receiver operating characteristic (ROC) curves for LRG1, CA19-9 and IL-6 demonstrated an area under the ROC curve of 0.98. In addition, raised LRG1 and CA19-9 were found to be independent predictors of BTC in the presence of elevated bilirubin, C-reactive protein and alkaline phosphatase. CONCLUSION: These results suggest LRG1, CA19-9 and IL-6 as useful markers for the diagnosis of BTC, particularly in high-risk patients with PSC.
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Neoplasias del Sistema Biliar/diagnóstico , Antígeno CA-19-9/sangre , Colangitis Esclerosante/diagnóstico , Colangitis/diagnóstico , Glicoproteínas/sangre , Interleucina-6/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVES: This study aims to establish three-dimensional (3D) cell culture models of human ovarian and endometrial cancers and to compare biological and morphological characteristics of these models with those of two-dimensional (2D) models of the same cell lines and the primary tumours. METHODS: 3D models of ovarian and endometrial cancer cell cultures were established using a Rotary Cell Culture System. Immunohistochemical profiling and differential proteomics were used to characterize biological characteristics of multicellular spheroids (MCS) formed from these cultures. These were compared to characteristics of the same cells established in 2D and of the primary tumours from which the cell lines were derived. RESULTS: MCSs from 3D cell cultures appeared histologically similar to the primary tumours. Immunohistochemical profiling of multiple markers, including CA125, BCL2 and p53, showed that patterns of protein expression in MCSs resemble those of the primary tumours. Proteomic profiling identified several differentially expressed protein markers between 2D and 3D cultures. These included prohibitin, which was down-regulated in 3D cultures suggesting cells proliferate less compared to 2D cultures; and VDAC1 and annexin 4, which were up-regulated in 3D cultures suggesting greater levels of apoptosis in 3D compared to 2D models. CONCLUSION: Establishing 3D models of cancer cell lines is likely to be of value for studying the molecular and biological mechanisms of ovarian/endometrial tumour progression and for testing novel molecular targets for cancer therapy.
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Neoplasias Endometriales/patología , Modelos Biológicos , Neoplasias Ováricas/patología , Esferoides Celulares/metabolismo , Esferoides Celulares/patología , Biomarcadores de Tumor/metabolismo , Antígeno Ca-125/metabolismo , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Proliferación Celular , Células Clonales/química , Células Clonales/metabolismo , Células Clonales/patología , Electroforesis en Gel Bidimensional , Células Epiteliales/citología , Células Epiteliales/metabolismo , Femenino , Humanos , Queratina-7/metabolismo , Antígeno Ki-67/metabolismo , Invasividad Neoplásica , Proteoma/análisis , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Esferoides Celulares/química , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
The three isoforms of the adaptor protein Shc play diverse roles in cell signalling. For example, the observation of p46 Shc in the nuclei of hepatocellular carcinoma cells suggests a function quite distinct from the better characterised cytoplasmic role. Ligands responsible for the transport of various Shc isoforms into organelles such as the nucleus have yet to be reported. To identify such ligands a far western approach was used to determine the p52 Shc interactome. The Ran-GTPase nuclear transport protein was identified and found to bind to p52 Shc in vitro with low micromolar affinity. Co-immunoprecipitation, pull down and fluorescence lifetime imaging microscopy experiments in stable cells confirmed cellular interaction and nuclear localisation. The nuclear transport factor protein NTF2, which functions in cohort with Ran, was shown to form a complex with both RAN and Shc, suggesting a mechanism for Shc entry into the nucleus as part of a tertiary complex.
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Núcleo Celular/metabolismo , Complejos Multiproteicos/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas Adaptadoras de la Señalización Shc/metabolismo , Proteína de Unión al GTP ran/metabolismo , Animales , Far-Western Blotting , Perros , Proteína Adaptadora GRB2/genética , Proteína Adaptadora GRB2/metabolismo , Humanos , Células Jurkat , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Isoformas de Proteínas/genética , Proteínas Adaptadoras de la Señalización Shc/genética , Transducción de Señal/fisiología , Proteína de Unión al GTP ran/genéticaRESUMEN
The success or not of ladybirds as biological control agents is dependent on both their foraging behaviour and their individual survival rates. The former is a function of the habitats they utilise; the latter, a consequence of their reproductive strategy. Egg clustering was investigated in two ladybird species, Aphidecta obliterata, a conifer specialist, and Adalia bipunctata, an arboreal woodland generalist. The effect of oviposition substrate (filter papers vs. spruce needles) on clutch size and oviposition preference was also tested. Adalia bipunctata laid significantly more eggs than A. obliterata. The size of egg clusters laid by the two coccinellids varied between species and substrate types. Adalia bipunctata laid larger egg clusters than A. obliterata, with batches reaching a maximum size of 32 eggs on spruce and 41 eggs on paper, while those of A. obliterata contained a maximum of 5 eggs on spruce and 9 eggs on paper. Of the clusters laid by A. obliterata, 18.6% of those on paper and 21.4% of those on spruce contained only a single egg, whereas a minimum of two eggs per cluster were laid by A. bipunctata. Smaller clusters were laid on the spruce cuttings by both species when compared with those laid on the filter paper, but A. obliterata laid significantly more eggs on spruce than on the filter paper (77% vs. 23%), whilst A. bipunctata laid significantly more eggs on the filter paper (91%). It is suggested that coccinellid eggs are more likely to be washed off spruce needles than broad leaves and that, by laying smaller egg clusters on spruce, A. obliterata reduces this risk. Adalia bipunctata usually lays its eggs on the underside of broad leaved trees and thus does not face this risk and thus can lay larger egg clusters. No differences in cannibalism rates were found between the two species. These findings have implications for the use of ladybirds as biological control agents in spruce forests.
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Canibalismo , Tamaño de la Nidada , Escarabajos/fisiología , Ecosistema , Oviposición/fisiología , Animales , Áfidos , Peso Corporal/fisiología , Femenino , Larva/fisiología , Óvulo , PiceaRESUMEN
The telomeric class III region of the major histocompatibility complex is gene dense, but apart from the three tumour necrosis factor (TNF) superfamily members (TNF, lymphotoxin alpha and lymphotoxin beta) little is known of the expression and function of the majority of the genes. Recent genetic studies in autoimmune diseases, particularly rheumatoid arthritis (RA), have suggested a human leukocyte antigen (HLA)-DR-independent disease effect in this region. To gain further insights into these associations, we used lipopolysaccharide-stimulated human macrophages to examine inducible mRNA expression and genotype-phenotype relationships for genes in this region. Following stimulation in addition to the expected induction of TNF mRNA, a 14-fold increase of ATP6V1G2 at 18 h (P<0.001) was seen, whereas B-associated transcript (BAT)2 (P<0.001) and leucocyte-specific transcript (LST)1 (P<0.001) were both downregulated. By genotyping single-nucleotide polymorphisms spanning a 70 kb interval centred on the TNF locus, we constructed haplotypes and determined associated expression profiles for 10 genes in the cluster using quantitative real-time polymerase chain reaction. Overexpression of BAT1 mRNA was associated with carriers of a haplotype containing the LST1 marker transmitted to RA cases in a family study and also DRB1(*)15 associated with susceptibility to nephritis in systemic lupus erythematosus. The implications of our findings for the understanding of genetic associations with disease susceptibility in this region are discussed.
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Enfermedades Autoinmunes/genética , Perfilación de la Expresión Génica , Predisposición Genética a la Enfermedad , Complejo Mayor de Histocompatibilidad/genética , Familia de Multigenes/genética , ARN Mensajero/metabolismo , Cartilla de ADN , Genotipo , Haplotipos/genética , Humanos , Lipopolisacáridos , Fenotipo , Polimorfismo de Nucleótido Simple , ARN Mensajero/genética , Telómero/genéticaRESUMEN
The effects and persistence of oviposition-deterring semiochemical cues from conspecific and heterospecific larval tracks on the oviposition rate of Aphidecta obliterata (Linnaeus) females were investigated. In addition, the effects of varying aphid prey density were considered and also whether any resulting response originated from differential nutritional status of females and/or due to aphid odour stimuli. The existence of oviposition responses to conspecific egg chemicals was also considered. Gravid A. obliterata females were deterred from oviposition by conspecific larval tracks and the effect was density dependent. Females actively avoided searching in these contaminated areas. Tracks induced a significant effect on oviposition for up to three days. Heterospecific tracks of the coccinellid Adalia bipunctata (Fabricius) or the chrysopid Chrysoperla carnea (Stephens) did not induce any oviposition response in A. obliterata females. Increasing aphid density induced increased oviposition rate in A. obliterata females. Nutritional status of females was an important factor in the relationship between aphid density and oviposition rate, but aphid associated cues (odours) were not. There was an inhibitory effect of extracts of conspecific egg-surface chemicals on oviposition by A. obliterata females. In the field, cannibalism, competition and limited food availability represent the major threats to egg and larval survival. Patch quality assessment mechanisms enable females to lay eggs at sites where offspring survival is maximized. Oviposition-deterring semiochemicals tend to promote more even distribution of predators over prey patches.
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Áfidos/crecimiento & desarrollo , Conducta Apetitiva/fisiología , Escarabajos/fisiología , Oviposición/fisiología , Análisis de Varianza , Animales , Áfidos/química , Señales (Psicología) , Femenino , Larva/fisiología , Oviposición/efectos de los fármacos , Óvulo/química , Control Biológico de Vectores/métodos , Densidad de Población , Conducta Predatoria , Olfato/fisiología , Especificidad de la Especie , Factores de TiempoRESUMEN
Microarray analysis offers a powerful tool for studying the mechanisms of cellular transformation, although the correlation between mRNA and protein expression is largely unknown. In this study, a microarray analysis was performed to compare transcription in response to overexpression of the ErbB-2 receptor tyrosine kinase in a model mammary luminal epithelial cell system, and in response to the ErbB-specific growth factor heregulin beta1. We sought to validate mRNA changes by monitoring changes at the protein level using a parallel proteomics strategy, and report a surprisingly high correlation between transcription and translation for the subset of genes studied. We further characterised the identified targets and relate differential expression to changes in the biological properties of ErbB-2-overexpressing cells. We found differential regulation of several key cell cycle modulators, including cyclin D2, and downregulation of a large number of interferon-inducible genes, consistent with increased proliferation of the ErbB-2-overexpressing cells. Furthermore, differential expression of genes involved in extracellular matrix modelling and cellular adhesion was linked to altered adhesion of these cells. Finally, we provide evidence for enhanced autocrine activation of MAPK signalling and the AP-1 transcription complex. Together, we have identified changes that are likely to drive proliferation and anchorage-independent growth of ErbB-2- overexpressing cancer cells.
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Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica , Genes erbB-2 , Glándulas Mamarias Humanas/citología , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/biosíntesis , Receptor ErbB-2/biosíntesis , Ciclo Celular , División Celular , Transformación Celular Neoplásica , Células Epiteliales/fisiología , Femenino , Humanos , Biosíntesis de Proteínas , Proteómica , ARN Mensajero/análisis , Transducción de Señal , Transcripción GenéticaRESUMEN
Mapping of disease susceptibility loci within the MHC has been partly hampered by the high degree of polymorphism of the HLA genes and the high level of linkage disequilibrium (LD) between markers within the MHC region. It is therefore important to identify new markers and determine the level of LD between HLA alleles and non-HLA genes. The NOTCH4 gene lies at the centromeric end of the MHC class III region, approximately 335 kb telomeric of the DRB1 locus. The encoded protein is an oncogene that is important in regulating vascular development and remodelling. A recent report has linked polymorphisms within NOTCH4 with risk of developing schizophrenia. We have investigated if coding polymorphisms exist within this gene and have identified three single nucleotide polymorphisms; a synonomous T to C transition at +1297 (HGBASE accession number SNP000064386), a synonomous A to G transition at +3061 (SNP000064387) and an A to G transition at +3063 which results in a replacement of glycine with aspartic acid at amino acid 279 (SNP000064388). The allele frequencies of +1297T, +3061A and +3063G were 0.65, 0.66 and 0.66, respectively. Linkage disequilibrium was detected both between these markers and with MHC alleles. These findings can be used in the fine mapping of disease susceptibility alleles within the MHC.
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Desequilibrio de Ligamiento , Complejo Mayor de Histocompatibilidad/genética , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas/genética , Receptores de Superficie Celular , Humanos , Receptor Notch4 , Receptores NotchRESUMEN
Alopecia areata is an inflammatory hair loss disease with a major genetic component. The presence of focal inflammatory lesions with perifollicular T-cell infiltrates reflects the importance of local cytokine production in the pathogenesis. In addition to its fundamental pro-inflammatory role, the interleukin-1 (IL-1) system has major effects on hair growth regulation in vitro, with the inhibitory actions of IL-1alpha and IL-1beta being opposed by the receptor antagonist IL-1ra. The novel interleukin-1 like molecule 1 (IL-1L1) which has greatest gene sequence homology with IL1RN, the gene encoding IL-1ra, is another potential IL-1 antagonist. In view of previous studies suggesting a significant role for IL1RN polymorphisms in the pathogenesis of autoimmune/inflammatory disease, we have analysed polymorphisms of IL-1ra (IL1RN+2018) and its homologue IL-1L1 (IL1L1+4734) in a case-control association study on 165 patients and a large number of matched controls. Homozygosity for the rare allele of IL1RN (IL1RN*2) was significantly associated with alopecia areata [odds ratio (OR) = 1.89, 95% CI (1.09, 3.28); P = 0.02], confirming our previous findings of significant association with the IL1RN variable number tandem repeat (VNTR). The results also revealed a novel association involving a polymorphism of the interleukin-1 receptor antagonist homologue IL1L1 at position + 4734, IL1RN+2018, and alopecia areata. The effect of a genotype combining three copies of the rare alleles at the IL1RN and IL1L1 loci conferred a more than additive increase in the risk of disease compared to IL1RN+2018 or IL1L1+4734 alone [OR 3.37 (1.60, 7.06); P = 0.002], suggesting possible synergy between the IL1RN and IL1L1 genes. This effect was stronger in patients with severe disease (alopecia totalis/universalis) [OR 4.62 (1.87, 11.40), P = 0.0022], and in those with early age at onset (< 20 years) [OR = 6.38 (2.64, 15.42), P = 0.0002]. Our results suggest that these polymorphisms within IL1RN and IL1L1 themselves or a gene in linkage disequilibrium with IL1RN and IL1L1 predispose to the more severe forms of alopecia areata.
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Alopecia Areata/genética , Interleucinas/genética , Sialoglicoproteínas/genética , Adulto , Epistasis Genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Homología de SecuenciaRESUMEN
The phosphoinositide 3-kinase (PI3K) family of enzymes is recruited upon growth factor receptor activation and produces 3' phosphoinositide lipids. The lipid products of PI3K act as second messengers by binding to and activating diverse cellular target proteins. These events constitute the start of a complex signaling cascade, which ultimately results in the mediation of cellular activities such as proliferation, differentiation, chemotaxis, survival, trafficking, and glucose homeostasis. Therefore, PI3Ks play a central role in many cellular functions. The factors that determine which cellular function is mediated are complex and may be partly attributed to the diversity that exists at each level of the PI3K signaling cascade, such as the type of stimulus, the isoform of PI3K, or the nature of the second messenger lipids. Numerous studies have helped to elucidate some of the key factors that determine cell fate in the context of PI3K signaling. For example, the past two years has seen the publication of many transgenic and knockout mouse studies where either PI3K or its signaling components are deregulated. These models have helped to build a picture of the role of PI3K in physiology and indeed there have been a number of surprises. This review uses such models as a framework to build a profile of PI3K function within both the cell and the organism and focuses, in particular, on the role of PI3K in cell regulation, immunity, and development. The evidence for the role of deregulated PI3K signaling in diseases such as cancer and diabetes is reviewed.
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Diferenciación Celular/fisiología , Transformación Celular Neoplásica/genética , Homeostasis/fisiología , Inmunidad , Fosfatidilinositol 3-Quinasas/fisiología , Transducción de Señal/inmunología , Animales , Activación Enzimática , Regulación Enzimológica de la Expresión Génica , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/fisiología , Metabolismo de los Lípidos , Fosfatidilinositol 3-Quinasas/química , Fosfatidilinositol 3-Quinasas/genética , Sistemas de Mensajero Secundario , Transducción de Señal/fisiologíaRESUMEN
The 3-phosphorylated inositol lipids fulfill roles as second messengers by interacting with the lipid binding domains of a variety of cellular proteins. Such interactions can affect the subcellular localization and aggregation of target proteins, and through allosteric effects, their activity. Generation of 3-phosphoinositides has been documented to influence diverse cellular pathways and hence alter a spectrum of fundamental cellular activities. This review is focused on the 3-phosphoinositide lipids, the synthesis of which is acutely triggered by extracellular stimuli, the enzymes responsible for their synthesis and metabolism, and their cell biological roles. Much knowledge has recently been gained through structural insights into the lipid kinases, their interaction with inhibitors, and the way their 3-phosphoinositide products interact with protein targets. This field is now moving toward a genetic dissection of 3-phosphoinositide action in a variety of model organisms. Such approaches will reveal the true role of the 3-phosphoinositides at the organismal level in health and disease.
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Fosfatidilinositol 3-Quinasas/química , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositoles/metabolismo , 1-Fosfatidilinositol 4-Quinasa/química , 1-Fosfatidilinositol 4-Quinasa/metabolismo , Actinas/metabolismo , Androstadienos/química , Androstadienos/farmacología , Animales , Apoptosis/fisiología , Sitios de Unión , Proteínas Sanguíneas/química , Dominio Catalítico , División Celular/fisiología , Cromonas/química , Cromonas/farmacología , Citoesqueleto/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Morfolinas/química , Morfolinas/farmacología , Fosfohidrolasa PTEN , Fosfatidilinositoles/química , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfoproteínas/química , Monoéster Fosfórico Hidrolasas/metabolismo , Homología de Secuencia de Aminoácido , Proteínas Supresoras de Tumor/metabolismo , WortmaninaRESUMEN
OBJECTIVE: Elevated RANTES serum levels are present in polymyalgia rheumatica (PMR) patients with active disease. Chemokines may contribute to the inflammatory PMR process through their binding to CC chemokine receptor 5 (CCR5). The aim of this study was to examine if the 32 base pair deletion allele in CCR5 (CCR5 delta 32 allele) might be associated with PMR susceptibility and influence the disease outcome. METHODS: We enrolled 88 consecutive patients with PMR residing in the Reggio Emilia area (Italy) who had a follow-up duration of at least one year. As a control group we used 86 healthy blood donors from the same geographic area. The CCR5 genotype of all PMR patients and controls was studied by polymerase chain reaction amplification of the region which includes the 32 deletion (CCR5 delta 32). RANTES serum levels were measured by commercial ELISA kits in CCR5 delta 32 heterozygous and CCR5 homozygous PMR patients at diagnosis before starting corticosteroid therapy and again after 6 months of therapy, as well as in 28 healthy subjects over 50 years of age. RESULTS: Frequencies of the CCR5 and CCR5 delta 32 alleles in patients and controls did not differ significantly. Homozygosity for CCR5 delta 32 was not detected in PMR patients and was detected in only one of the controls. No significant differences were observed between the patients carrying the CCR5 delta 32 allele and those homozygous for the normal CCR5 allele when we compared sex, presence of distal synovitis and systemic signs and/or symptoms, initial and cumulative prednisone dose, duration of therapy, ESR at diagnosis, frequency of relapse/recurrence and RANTES serum levels at diagnosis and after 6 months of corticosteroids. CONCLUSION: These results indicate that the frequency of the 32 deletion of the CCR5 receptor was not significantly different between PMR patients and healthy controls, and this genotype does not appear to be associated with the susceptibility to or severity of PMR.
Asunto(s)
Polimorfismo Genético , Polimialgia Reumática/genética , Receptores CCR5/genética , Corticoesteroides/uso terapéutico , Anciano , Anciano de 80 o más Años , Alelos , Emparejamiento Base , Quimiocina CCL5/sangre , Femenino , Eliminación de Gen , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimialgia Reumática/tratamiento farmacológico , Valores de ReferenciaRESUMEN
Fibrosing alveolitis (FA) is characterized by persistent inflammation and elevated production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta), and interleukin-1 receptor antagonist (IL-1ra) in the lung. Single base variations at position +2018 in the IL-1ra gene (IL-1RN) and position -308 in the TNF-alpha gene (TNF-A) are overrepresented in other chronic inflammatory disease populations. We have tested the hypothesis that predisposition to FA may also be influenced by these polymorphisms by genotyping 88 cases and matched controls from England and 61 cases and 103 unmatched controls from Italy. The rarer allele for IL-1RN and TNF-A was designated allele 2 in each case. For IL-1RN allele 2, in the English group, the relative odds of FA were increased in homozygous subjects by an odds ratio (OR) of 10.2 (95% confidence intervals [CI], 1.26 to 81.4; p = 0.03) and for carriers by an OR of 1.85 (95% CI, 0.94 to 3.63; p = 0.075). In the Italian population, the risk of FA was increased, in IL-1RN allele 2 homozygotes (OR, 2.54; 95% CI, 0.68 to 9.50; p = 0.2) and in carriers (OR 2.40; 95% CI, 1.26 to 4.60; p = 0.008). Carriage of TNF-A allele 2 was also associated with increased risk of FA in the English (OR, 1.85; 95% CI, 0.94 to 3.63; p = 0.075) and Italian (OR, 2.50; 95% CI, 1.14 to 5.47; p = 0.022) populations. These data suggest IL-1RN (+2018) allele 2 and TNF-A (-308) allele 2 confer increased risk of developing FA and, therefore, that unopposed IL-1beta and/or excessive TNF-alpha may play a pathophysiologic role in this condition.