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INTRODUCTION: Plain radiographs are a globally ubiquitous means of investigation for injuries to the musculoskeletal system. Despite this, initial interpretation remains a challenge and inaccuracies give rise to adverse sequelae for patients and healthcare providers alike. This study sought to address the limited, existing meta-analytic research on the initial reporting of radiographs for skeletal trauma, with specific regard to diagnostic accuracy of the most commonly injured region of the appendicular skeleton, the lower limb. METHOD: A prospectively registered, systematic review and meta-analysis was performed using published research from the major clinical-science databases. Studies identified as appropriate for inclusion underwent methodological quality and risk of bias analysis. Meta-analysis was then performed to establish summary rates for specificity and sensitivity of diagnostic accuracy, including covariates by anatomical site, using HSROC and bivariate models. RESULTS: A total of 3887 articles were screened, with 10 identified as suitable for analysis based on the eligibility criteria. Sensitivity and specificity across the studies were 93.5% and 89.7% respectively. Compared with other anatomical subdivisions, interpretation of ankle radiographs yielded the highest sensitivity and specificity, with values of 98.1% and 94.6% respectively, and a diagnostic odds ratio of 929.97. CONCLUSION: Interpretation of lower limb skeletal radiographs operates at a reasonably high degree of sensitivity and specificity. However, one in twenty true positives is missed on initial radiographic interpretation and safety netting systems need to be established to address this. Virtual fracture clinic reviews and teleradiology services in conjunction with novel technology will likely be crucial in these circumstances.
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Extremidad Inferior , Humanos , Extremidad Inferior/diagnóstico por imagen , Radiografía , Sensibilidad y EspecificidadRESUMEN
Improvements in immunosuppression have modified short-term survival of deceased-donor allografts, but not their rate of long-term failure. Mismatches between donor and recipient HLA play an important role in the acute and chronic allogeneic immune response against the graft. Perfect matching at clinically relevant HLA loci does not obviate the need for immunosuppression, suggesting that additional genetic variation plays a critical role in both short- and long-term graft outcomes. By combining patient data and samples from supranational cohorts across the United Kingdom and European Union, we performed the first large-scale genome-wide association study analyzing both donor and recipient DNA in 2094 complete renal transplant-pairs with replication in 5866 complete pairs. We studied deceased-donor grafts allocated on the basis of preferential HLA matching, which provided some control for HLA genetic effects. No strong donor or recipient genetic effects contributing to long- or short-term allograft survival were found outside the HLA region. We discuss the implications for future research and clinical application.
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Estudio de Asociación del Genoma Completo , Trasplante de Riñón , Donantes de Tejidos , Receptores de Trasplantes , Adulto , Replicación del ADN , Femenino , Genotipo , Supervivencia de Injerto/inmunología , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Trasplante HomólogoRESUMEN
OBJECTIVE: Hyperuricaemia and gout are well-recognized complications of diuretic use. The aim of this study was to examine the clinical and genetic features of diuretic-associated gout. METHODS: Participants (n = 1365) fulfilling the 1977 ARA gout classification criteria, recruited from primary and secondary care, attended a study visit that included a detailed clinical assessment. Use of diuretic therapy was recorded during the study visit, and was confirmed by electronic dispensing data [n = 426 (31.2%) on diuretics]. Gout-associated single nucleotide polymorphisms were genotyped. Clinical and genetic features of diuretic-associated gout were analysed using a case-control study design (diuretics vs no diuretics). RESULTS: In the diuretic group there were more women, higher rates of comorbid conditions, higher BMI and lower estimated glomerular filtration rate compared with those not taking diuretics. Gout disease duration, frequency of gout flares and presence of tophi were similar in the two groups. Patients on diuretics had higher age of gout presentation and higher recorded serum urate. The ABCG2 rs2231142 risk allele was present less frequently in the diuretic group (36.1%) compared with those not on diuretics (47.6%, P = 1.2 × 10(-4)). The differences in ABCG2 were observed in both men and women with gout. CONCLUSION: Diuretic-associated gout represents a medically complex condition. Although age of gout onset is later and serum urate concentrations are higher in those on diuretics, other clinical features of gout are similar. The observed differences in the ABCG2 risk allele frequency suggest that some genetic factors play a less dominant role in diuretic-associated gout compared with primary gout.
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Diuréticos/efectos adversos , Gota/inducido químicamente , Gota/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/sangre , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Adulto , Edad de Inicio , Anciano , Alelos , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Genotipo , Gota/sangre , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/sangre , Proteínas de Neoplasias/genética , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Ácido Úrico/sangreRESUMEN
A practical and highly effective one-pot synthesis of versatile heteroaryl ketones directly from carboxylic acids and heteroaryl halides under mild conditions is reported. This method does not require derivatization of carboxylic acids (preparation of acid chlorides, Weinreb amides, etc.) or the use of any additives/catalysts. A wide substrate scope of carboxylic acids with high functional group tolerance has also been demonstrated. The results reveal that the presence of an α-nitrogen on the halide substrate greatly improves the desired ketone formation.
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OBJECTIVES: MicroRNAs (miRNA) are small non-coding RNAs that function as post-transcriptional repressors of gene expression. We hypothesised that miRNA regulate gene expression of proinflammatory cytokines in response to monosodium urate (MSU) crystals. METHODS: We stimulated human monocytic THP-1 cells with MSU crystals and examined miRNA and proinflammatory cytokine gene expression. The effects of miR-146a overexpression were examined by transfecting THP-1 cells with miR-146a precursor. miR-146a expression was examined in the urate peritonitis model, in peripheral blood mononuclear cells from people with gout and control participants, and in gouty tophus samples. RESULTS: MSU crystals increased miR-146a expression in THP-1 cells, but not other miRNA implicated in interleukin (IL)-1ß regulation. Overexpression of miR-146a expression reduced MSU crystal-induced IL-1ß, tumour necrosis factor-α (TNFα), monocyte chemoattractant protein-1 (MCP-1) and IL-8 gene expression. In the urate peritonitis model, reduced miR-146a expression was observed during the acute inflammatory response to MSU crystal injection. In people with intercritical gout, peripheral blood mononuclear cells expressed significantly higher levels of miR-146a, compared with normouricaemic and hyperuricaemic control participants and those with acute gout flares. Expression of miR-146a was also observed in all tophus samples. CONCLUSIONS: Collectively, these data suggest that miR-146a is a transcriptional brake that is lost during the acute inflammatory response to MSU crystals.
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Gota/genética , MicroARNs/genética , Animales , Antioxidantes/farmacología , Estudios de Casos y Controles , Línea Celular , Modelos Animales de Enfermedad , Femenino , Expresión Génica/efectos de los fármacos , Gota/metabolismo , Humanos , Hiperuricemia/genética , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Masculino , Ratones , MicroARNs/efectos de los fármacos , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ácido Úrico/farmacologíaRESUMEN
BACKGROUND: The aim of this study was to compare the frequency and volume of dual energy CT (DECT) urate deposits in people with asymptomatic hyperuricaemia and symptomatic gout. METHODS: We analysed DECT scans of the feet from asymptomatic individuals with serum urate ≥540â µmol/L (n=25) and those with crystal proven gout without clinically apparent tophi (n=33). RESULTS: DECT urate deposits were observed in 6/25 (24%) participants with asymptomatic hyperuricaemia, 11/14 (79%) with early gout (predefined as disease duration ≤3â years) and 16/19 (84%) with late gout (p<0.001). DECT urate deposition was observed in both joints and tendons in the asymptomatic hyperuricaemia group, but significantly less frequently than in those with gout (p≤0.001 for both joint and tendon sites). The volume of urate deposition was also significantly lower in those with asymptomatic hyperuricaemia, compared with the early and the late gout groups (p<0.01 for both comparisons). Similar urate volumes were observed in the early and late gout groups. CONCLUSIONS: Although subclinical urate deposition can occur in people with asymptomatic hyperuricaemia, these deposits occur more frequently and at higher volumes in those with symptomatic gout. These data suggest that a threshold of urate crystal volume may be required before symptomatic disease occurs.
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Articulaciones del Pie/diagnóstico por imagen , Gota/diagnóstico por imagen , Hiperuricemia/diagnóstico por imagen , Tendones/diagnóstico por imagen , Ácido Úrico/sangre , Absorciometría de Fotón , Anciano , Enfermedades Asintomáticas , Estudios Transversales , Femenino , Pie/diagnóstico por imagen , Gota/sangre , Humanos , Hiperuricemia/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tomografía Computarizada por Rayos XRESUMEN
Phospho- and sphingolipids are crucial cellular and intracellular compounds. These lipids are required for active transport, a number of enzymatic processes, membrane formation, and cell signalling. Disruption of their metabolism leads to several diseases, with diverse neurological, psychiatric, and metabolic consequences. A large number of phospholipid and sphingolipid species can be detected and measured in human plasma. We conducted a meta-analysis of five European family-based genome-wide association studies (Nâ=â4034) on plasma levels of 24 sphingomyelins (SPM), 9 ceramides (CER), 57 phosphatidylcholines (PC), 20 lysophosphatidylcholines (LPC), 27 phosphatidylethanolamines (PE), and 16 PE-based plasmalogens (PLPE), as well as their proportions in each major class. This effort yielded 25 genome-wide significant loci for phospholipids (smallest P-valueâ=â9.88×10(-204)) and 10 loci for sphingolipids (smallest P-valueâ=â3.10×10(-57)). After a correction for multiple comparisons (P-value<2.2×10(-9)), we observed four novel loci significantly associated with phospholipids (PAQR9, AGPAT1, PKD2L1, PDXDC1) and two with sphingolipids (PLD2 and APOE) explaining up to 3.1% of the variance. Further analysis of the top findings with respect to within class molar proportions uncovered three additional loci for phospholipids (PNLIPRP2, PCDH20, and ABDH3) suggesting their involvement in either fatty acid elongation/saturation processes or fatty acid specific turnover mechanisms. Among those, 14 loci (KCNH7, AGPAT1, PNLIPRP2, SYT9, FADS1-2-3, DLG2, APOA1, ELOVL2, CDK17, LIPC, PDXDC1, PLD2, LASS4, and APOE) mapped into the glycerophospholipid and 12 loci (ILKAP, ITGA9, AGPAT1, FADS1-2-3, APOA1, PCDH20, LIPC, PDXDC1, SGPP1, APOE, LASS4, and PLD2) to the sphingolipid pathways. In large meta-analyses, associations between FADS1-2-3 and carotid intima media thickness, AGPAT1 and type 2 diabetes, and APOA1 and coronary artery disease were observed. In conclusion, our study identified nine novel phospho- and sphingolipid loci, substantially increasing our knowledge of the genetic basis for these traits.
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Genoma Humano , Estudio de Asociación del Genoma Completo , Fosfolípidos , Esfingolípidos , Población Blanca/genética , Grosor Intima-Media Carotídeo , Bases de Datos Genéticas , delta-5 Desaturasa de Ácido Graso , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/genética , Sitios Genéticos , Humanos , Fosfolípidos/sangre , Fosfolípidos/genética , Polimorfismo de Nucleótido Simple , Esfingolípidos/sangre , Esfingolípidos/genéticaRESUMEN
BACKGROUND: Speciality training in oral and maxillofacial pathology (OMFP) across the world would be aided by guidance on a generic curriculum and training programme that all countries could use as a template. In order to facilitate this, we require an understanding of the various forms which OMFP training takes across the world. METHODS: We sent a questionnaire to OMF pathologists in the 42 countries represented in the IAOP membership, via their Regional Councillor. The questionnaire included detailed demographics, entry requirements, specialty training program and facilities/resources. RESULTS: Replies were received from 22/42 countries (52%). OMFP is a dental/dental and medical speciality in 72%, and in 92% of those, this is recognised by a licensing board. Training was undertaken in an academic environment in 85% (with many offering a further academic qualification) and the median length of training was 4 years. General/anatomical pathology training is mandated in 85% of programs and a common core of general sub-specialities was identified. An end of training assessment was conducted in 80% of programs with most including written, practical and oral elements. Training program directors and educational supervisors were in place in 12/16 programs and, in most, Quality Assurance of training was externally monitored. In only one country was the number of trainees linked to workforce planning. CONCLUSIONS: Training in OMFP varies across the world. However, we feel there is sufficient commonality for the development of an agreed indicative framework on education and training in Oral and Maxillofacial Pathology, perhaps under the auspices of the IAOP.
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Patología Bucal/educación , Especialidades Odontológicas/educación , Acreditación , Competencia Clínica , Curriculum , Evaluación Educacional/métodos , Humanos , Internacionalidad , Licencia en Odontología , Licencia Médica , Patología Bucal/normas , Garantía de la Calidad de Atención de Salud , Facultades de Odontología , Facultades de Medicina , Especialidades Odontológicas/normas , Encuestas y CuestionariosRESUMEN
The antioxidant glutathione (GSH) plays a critical role in maintaining intracellular redox homeostasis but in tumors the GSH biosynthetic pathway is often dysregulated, contributing to tumor resistance to radiation and chemotherapy. Glutamate-cysteine ligase (GCL) catalyzes the first and rate-limiting reaction in GSH synthesis, and enzyme function is controlled by GSH feedback inhibition or by transcriptional upregulation of the catalytic (GCLC) and modifier (GCLM) subunits. However, it has recently been reported that the activity of GCLC and the formation of GCL can be modified by reactive aldehyde products derived from lipid peroxidation. Due to the susceptibility of GCLC to posttranslational modifications by reactive aldehydes, we examined the potential for 2-deoxy-D-ribose (2dDR) to glycate GCLC and regulate enzyme activity and GCL formation. 2dDR was found to directly modify both GCLC and GCLM in vitro, resulting in a significant inhibition of GCLC and GCL enzyme activity without altering substrate affinity or feedback inhibition. 2dDR-mediated glycation also inhibited GCL subunit heterodimerization and formation of the GCL holoenzyme complex while not causing dissociation of pre-formed holoenzyme. This PTM could be of particular importance in glioblastoma (GBM) where intratumoral necrosis provides an abundance of thymidine, which can be metabolized by thymidine phosphorylase (TP) to form 2dDR. TP is expressed at high levels in human GBM tumors and shRNA knockdown of TP in U87 GBM cells results in a significant increase in cellular GCL enzymatic activity.
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Neoplasias Encefálicas/metabolismo , Desoxirribosa/metabolismo , Resistencia a Antineoplásicos , Glioblastoma/metabolismo , Glucosa/metabolismo , Glutamato-Cisteína Ligasa/metabolismo , Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/patología , Catálisis , Línea Celular Tumoral , Electroforesis en Gel de Poliacrilamida , Glioblastoma/enzimología , Glioblastoma/patología , Humanos , Cinética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Sphingolipids have essential roles as structural components of cell membranes and in cell signalling, and disruption of their metabolism causes several diseases, with diverse neurological, psychiatric, and metabolic consequences. Increasingly, variants within a few of the genes that encode enzymes involved in sphingolipid metabolism are being associated with complex disease phenotypes. Direct experimental evidence supports a role of specific sphingolipid species in several common complex chronic disease processes including atherosclerotic plaque formation, myocardial infarction (MI), cardiomyopathy, pancreatic beta-cell failure, insulin resistance, and type 2 diabetes mellitus. Therefore, sphingolipids represent novel and important intermediate phenotypes for genetic analysis, yet little is known about the major genetic variants that influence their circulating levels in the general population. We performed a genome-wide association study (GWAS) between 318,237 single-nucleotide polymorphisms (SNPs) and levels of circulating sphingomyelin (SM), dihydrosphingomyelin (Dih-SM), ceramide (Cer), and glucosylceramide (GluCer) single lipid species (33 traits); and 43 matched metabolite ratios measured in 4,400 subjects from five diverse European populations. Associated variants (32) in five genomic regions were identified with genome-wide significant corrected p-values ranging down to 9.08x10(-66). The strongest associations were observed in or near 7 genes functionally involved in ceramide biosynthesis and trafficking: SPTLC3, LASS4, SGPP1, ATP10D, and FADS1-3. Variants in 3 loci (ATP10D, FADS3, and SPTLC3) associate with MI in a series of three German MI studies. An additional 70 variants across 23 candidate genes involved in sphingolipid-metabolizing pathways also demonstrate association (p = 10(-4) or less). Circulating concentrations of several key components in sphingolipid metabolism are thus under strong genetic control, and variants in these loci can be tested for a role in the development of common cardiovascular, metabolic, neurological, and psychiatric diseases.
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Esfingolípidos/sangre , Población Blanca/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , delta-5 Desaturasa de Ácido Graso , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Linaje , Polimorfismo de Nucleótido Simple , Adulto JovenRESUMEN
Glutamate cysteine ligase (GCL) catalyzes the rate-limiting step in the formation of the cellular antioxidant glutathione (GSH). The GCL holoenzyme consists of two separately coded proteins, a catalytic subunit (GCLC) and a modifier subunit (GCLM). Both GCLC and GLCM are controlled transcriptionally by a variety of cellular stimuli, including oxidative stress. This study addresses post-translational control of GCL activity, which increased rapidly in human lymphocytes following oxidative stress. Activation of GCL occurred within minutes of treatment and without any change in GCL protein levels and coincided with an increase in the proportion of GCLC in the holoenzyme form. Likewise, GCLM shifted from the monomeric form to holoenzyme and higher molecular weight species. Normal rat tissues also showed a distribution of monomeric and higher molecular weight forms. Neither GCL activation, nor the formation of holoenzyme, required a covalent intermolecular disulfide bridge between GCLC and GCLM. However, in immunoprecipitation studies, a neutralizing epitope associated with enzymatic activity was protected following cellular oxidative stress. Thus, the N-terminal portion of GCLC may undergo a change that stabilizes the GCL holoenzyme. Our results suggest that a dynamic equilibrium exists between low and high activity forms of GCL and is altered by transient oxidative stress. This provides a mechanism for the rapid post-translational activation of GCL and maintenance of cellular GSH homeostasis.
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Glutamato-Cisteína Ligasa/metabolismo , Glutatión/metabolismo , Homeostasis/fisiología , Estrés Oxidativo/fisiología , Transcripción Genética/fisiología , Animales , Disulfuros/metabolismo , Activación Enzimática/fisiología , Holoenzimas/metabolismo , Humanos , Células Jurkat , Linfocitos/enzimología , Ratones , Especificidad de Órganos/fisiología , Estructura Terciaria de Proteína , RatasRESUMEN
Genes for height have gained interest for decades, but only recently have candidate genes started to be identified. We have performed linkage analysis and genome-wide association for height in approximately 4000 individuals from five European populations. A total of five chromosomal regions showed suggestive linkage and in one of these regions, two SNPs (rs849140 and rs1635852) were associated with height (nominal P = 7.0 x 10(-8) and P = 9.6 x 10(-7), respectively). In total, five SNPs across the genome showed an association with height that reached the threshold of genome-wide significance (nominal P < 1.6 x 10(-7)). The association with height was replicated for two SNPs (rs1635852 and rs849140) using three independent studies (n = 31 077, n=1268 and n = 5746) with overall meta P-values of 9.4 x 10(-10) and 5.3 x 10(-8). These SNPs are located in the JAZF1 gene, which has recently been associated with type II diabetes, prostate and endometrial cancer. JAZF1 is a transcriptional repressor of NR2C2, which results in low IGF1 serum concentrations, perinatal and early postnatal hypoglycemia and growth retardation when knocked out in mice. Both the linkage and association analyses independently identified the JAZF1 region affecting human height. We have demonstrated, through replication in additional independent populations, the consistency of the effect of the JAZF1 SNPs on height. Since this gene also has a key function in the metabolism of growth, JAZF1 represents one of the strongest candidates influencing human height identified so far.
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Estatura/genética , Ligamiento Genético , Estudio de Asociación del Genoma Completo , Proteínas de Neoplasias/genética , Proteínas Co-Represoras , Proteínas de Unión al ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Población Blanca/genéticaRESUMEN
Estimating individual genome-wide autozygosity is important both in the identification of recessive disease variants via homozygosity mapping and in the investigation of the effects of genome-wide homozygosity on traits of biomedical importance. Approaches have tended to involve either single-point estimates or rather complex multipoint methods of inferring individual autozygosity, all on the basis of limited marker data. Now, with the availability of high-density genome scans, a multipoint, observational method of estimating individual autozygosity is possible. Using data from a 300,000 SNP panel in 2618 individuals from two isolated and two more-cosmopolitan populations of European origin, we explore the potential of estimating individual autozygosity from data on runs of homozygosity (ROHs). Termed F(roh), this is defined as the proportion of the autosomal genome in runs of homozygosity above a specified length. Mean F(roh) distinguishes clearly between subpopulations classified in terms of grandparental endogamy and population size. With the use of good pedigree data for one of the populations (Orkney), F(roh) was found to correlate strongly with the inbreeding coefficient estimated from pedigrees (r = 0.86). Using pedigrees to identify individuals with no shared maternal and paternal ancestors in five, and probably at least ten, generations, we show that ROHs measuring up to 4 Mb are common in demonstrably outbred individuals. Given the stochastic variation in ROH number, length, and location and the fact that ROHs are important whether ancient or recent in origin, approaches such as this will provide a more useful description of genomic autozygosity than has hitherto been possible.
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Genoma Humano , Homocigoto , Linaje , Población Blanca/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Haplotipos , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The first detailed description of calcifying epithelial odontogenic tumor (CEOT) are ascribed to Jens Pindborg, but this tumor was described some years previously. Subsequently, CEOT was included in the 1971 WHO classification of odontogenic tumors and a since then number of variants have been described, which have added confusion to the diagnostic criteria. We aimed to survey the literature on the variants of CEOT, in parallel with a review of our single institution experience of CEOTs. Cases identified were collated, including available clinical, radiological and histological information and then reviewed, taking into account changes in the understanding and classifications of odontogenic tumors since initial diagnosis. We identified 26 cases from 1975 to 2017 for which histological material was available. Of these, only 13 (50%) showed the "classic" histological appearance, whilst two cases were identified as recognized variants. In 11 cases, other diagnoses or a differential diagnosis were preferred, with no agreed diagnosis in four of these. The proliferation fraction (Ki67) in the 10 cases tested was 2.1% ± 0.18. These findings illustrate the diagnostic challenges in this group of tumors and highlight the gaps in knowledge. Techniques, such as EWSR1 gene cytogenetic analysis, may be helpful in cases with clear cells. However, in other areas of controversy, including the non-calcifying and Langerhans cell rich variants, further investigation, perhaps utilizing sequencing technologies may be needed to refine the classification. Owing to the relative rarity of these lesions it would be beneficial if future work could be pursued as an international collaboration.
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Tumores Odontogénicos/patología , Neoplasias Cutáneas/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Genome-wide association (GWA) studies have identified around 20 common genetic variants influencing the risk of type 2 diabetes (T2D). Likewise, a number of variants have been associated with diabetes-related quantitative glycaemic traits, but to date the overlap between these genes and variants has been low. The majority of genetic studies have focused on fasting plasma glucose levels; however, this measure is highly variable. We have conducted a GWA meta-analysis of glycated haemoglobin (HbA1(C) ) levels within three healthy nondiabetic populations. This phenotype provides an estimate of mean glucose levels over 2-3 months and is a more stable predictor of future diabetes risk. Participants were from three isolated populations: the Orkney Isles in the north of Scotland, the Dalmatian islands of Vis, and Korcula in Croatia (total of 1782 nondiabetic subjects). Association was tested in each population and results combined by meta-analysis. The strongest association was with the TCF7L2 gene (rs7903146, P= 1.48 × 10â»7). This is also the strongest common genetic risk factor for T2D but it has not been identified in previous genome-wide studies of glycated haemoglobin.
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Diabetes Mellitus Tipo 2/genética , Estudio de Asociación del Genoma Completo , Hemoglobina Glucada/genética , Proteína 2 Similar al Factor de Transcripción 7/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Croacia/epidemiología , Diabetes Mellitus Tipo 2/sangre , Femenino , Genotipo , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Escocia/epidemiología , Adulto JovenRESUMEN
UNLABELLED: Drug-induced liver injury (DILI) is a challenging problem in drug development and clinical practice. Patient susceptibility to DILI is multifactorial, making these reactions difficult to predict and prevent. Clinical observations have suggested that concurrent bacterial and viral infections represent an important risk factor in determining patient susceptibility to developing adverse drug reactions, although the underlying mechanism is not clear. In the present study, we employed the viral RNA mimetic (polyinosinic-polycytidylic acid [polyI:C]) to emulate viral infection and examined its effect on halothane-induced liver injury. Although pretreatment of mice with polyI:C attenuated halothane hepatotoxicity due to its inhibitory effect on halothane metabolism, posttreatment significantly exacerbated liver injury with hepatocellular apoptosis being significantly higher than that in mice treated with polyI:C alone or halothane alone. The pan-caspase inhibitor z-VAD-fmk suppressed liver injury induced by polyI:C/posthalothane cotreatment, suggesting that the increased hepatocyte apoptosis contributes to the exacerbation of liver injury. Posttreatment with polyI:C also caused activation of hepatic Kupffer cells (KCs) and natural killer (NK) cells and upregulated multiple proapoptotic factors, including tumor necrosis factor-alpha (TNF-alpha), NK receptor group 2, member D (NKG2D), and Fas ligand (FasL). These factors may play important roles in mediating polyI:C-induced hepatocyte apoptosis. CONCLUSION: This is the first study to provide evidence that concurrent viral infection can inhibit cytochrome (CYP)450 activities and activate the hepatic innate immune system to proapoptotic factors. DILI may be attenuated or exacerbated by pathogens depending on the time of infection.
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Halotano/toxicidad , Hígado/efectos de los fármacos , Poli I-C/farmacología , Clorometilcetonas de Aminoácidos/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Inhibidores de Caspasas , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Proteína Ligando Fas/metabolismo , Femenino , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Macrófagos del Hígado/inmunología , Macrófagos del Hígado/fisiología , Ratones , Ratones Endogámicos BALB C , Poli I-C/toxicidad , Factores de Tiempo , Factor de Necrosis Tumoral alfa/fisiologíaRESUMEN
The glutathione (GSH) antioxidant defense system plays a central role in protecting mammalian cells against oxidative injury. Glutamate cysteine ligase (GCL) is the rate-limiting enzyme in GSH biosynthesis and is a heterodimeric holoenzyme composed of catalytic (GCLC) and modifier (GCLM) subunits. As a means of assessing the cytoprotective effects of enhanced GSH biosynthetic capacity, we have developed a protein transduction approach whereby recombinant GCL protein can be rapidly and directly transferred into cells when coupled to the HIV TAT protein transduction domain. Bacterial expression vectors encoding TAT fusion proteins of both GCL subunits were generated and recombinant fusion proteins were synthesized and purified to near homogeneity. The TAT-GCL fusion proteins were capable of heterodimerization and formation of functional GCL holoenzyme in vitro. Exposure of Hepa-1c1c7 cells to the TAT-GCL fusion proteins resulted in the time- and dose-dependent transduction of both GCL subunits and increased cellular GCL activity and GSH levels. A heterodimerization-competent, enzymatically deficient GCLC-TAT mutant was also generated in an attempt to create a dominant-negative suppressor of GCL. Transduction of cells with a catalytically inactive GCLC(E103A)-TAT mutant decreased cellular GCL activity in a dose-dependent manner. TAT-mediated manipulation of cellular GCL activity was also functionally relevant as transduction with wild-type GCLC(WT)-TAT or mutant GCLC(E103A)-TAT conferred protection or enhanced sensitivity to H(2)O(2)-induced cell death, respectively. These findings demonstrate that TAT-mediated transduction of wild-type or dominant-inhibitory mutants of the GCL subunits is a viable means of manipulating cellular GCL activity to assess the effects of altered GSH biosynthetic capacity.
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Glutamato-Cisteína Ligasa/metabolismo , Glutatión/biosíntesis , Oxidantes/toxicidad , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular , Regulación Enzimológica de la Expresión Génica , Glutamato-Cisteína Ligasa/genética , Ratones , Mutación , Subunidades de ProteínaRESUMEN
We report an SAR study of MC4R analogs containing spiroindane heterocyclic privileged structures. Compound 26 with N-Me-1,2,4-triazole moiety possesses exceptional potency at MC4R and potent anti-obesity efficacy in a mouse model. However, the efficacy is not completely mediated through MC4R. Additional SAR studies led to the discovery of compound 32, which is more potent at MC4R. Compound 32 demonstrates MC4R mediated anti-obesity efficacy in rodent models.
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Obesidad/tratamiento farmacológico , Receptor de Melanocortina Tipo 4/agonistas , Triazoles/farmacología , Animales , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados , Estructura Molecular , Ratas , Receptor de Melanocortina Tipo 4/genética , Relación Estructura-Actividad , Triazoles/química , Triazoles/uso terapéuticoRESUMEN
We report a series of potent and selective MC4R agonists based on spiroindane amide privileged structures for potential treatments of obesity. Among the synthetic methods used, Method C allows rapid synthesis of the analogs. The series of compounds can afford high potency on MC4R as well as good rodent pharmacokinetic profiles. Compound 1r (MK-0489) demonstrates MC4R mediated reduction of food intake and body weight in mouse models. Compound 1r is efficacious in 14-day diet-induced obese (DIO) rat models.
Asunto(s)
Amidas/química , Fármacos Antiobesidad/química , Obesidad/tratamiento farmacológico , Pirrolidinas/química , Receptor de Melanocortina Tipo 4/agonistas , Compuestos de Espiro/química , Amidas/farmacocinética , Amidas/uso terapéutico , Animales , Fármacos Antiobesidad/farmacocinética , Fármacos Antiobesidad/uso terapéutico , Peso Corporal/efectos de los fármacos , Humanos , Ratones , Ratones Noqueados , Pirrolidinas/farmacocinética , Pirrolidinas/uso terapéutico , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 4/metabolismo , Compuestos de Espiro/farmacocinética , Compuestos de Espiro/uso terapéutico , Relación Estructura-ActividadRESUMEN
We report the design, synthesis and properties of spiroindane based compound 1, a potent, selective, orally bioavailable, non-peptide melanocortin subtype-4 receptor agonist. Compound 1 shows excellent erectogenic activity in the rodent models.