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The Bacteroides are a numerically dominant genus of the human intestinal microbiota. These organisms harbor a rare bacterial pathway for incorporation of exogenous fucose into capsular polysaccharides and glycoproteins. The infrequency of glycoprotein synthesis by bacteria prompted a more detailed analysis of this process. Here, we demonstrate that Bacteroides fragilis has a general O-glycosylation system. The proteins targeted for glycosylation include those predicted to be involved in protein folding, protein-protein interactions, peptide degradation as well as surface lipoproteins. Protein glycosylation is central to the physiology of B. fragilis and is necessary for the organism to competitively colonize the mammalian intestine. We provide evidence that general O-glycosylation systems are conserved among intestinal Bacteroides species and likely contribute to the predominance of Bacteroides in the human intestine.
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Proteínas Bacterianas/metabolismo , Bacteroides fragilis/fisiología , Glicoproteínas/metabolismo , Intestinos/microbiología , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Bacteroides/fisiología , Vida Libre de Gérmenes , Glicoproteínas/análisis , Glicoproteínas/genética , Glicosilación , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Polisacáridos Bacterianos/metabolismoRESUMEN
GLI1-altered mesenchymal tumors are an emerging entity in soft tissue pathology. In the head and neck region, they are most commonly in the tongue. Limited published data indicate a propensity for local recurrence, regional spread, and distant metastasis in both GLI1-rearranged and GLI1-amplified tumors. The purpose of this report is to present the rare case of a GLI1-amplified spindle cell tumor of the orbit and a focused review of the literature. A 54-year-old woman presented with proptosis, eye pain, and ocular motility restriction in the left eye. Imaging demonstrated a tumor occupying the superomedial intraconal orbit that was distinct from the extraocular muscles, optic nerve, and globe. The tumor was totally resected with a combined open transorbital and endoscopic, endonasal approach. Pathological analysis demonstrated a spindled and epithelioid mesenchymal tumor with diffuse nuclear GLI1 expression. PCR-based, next*-generation sarcoma fusion panel was negative for GLI1 fusions, including GLI1::ACTB fusions; however, DDIT3 breaks apart fluorescence in situ hybridization (FISH), which can be used as a surrogate for GLI1 alterations due to proximity to 12q13.3, showing amplification. Post-operatively, the patient had recovered visual acuity. She received adjuvant radiation therapy (60 Gy in 30 fractions). Surveillance for recurrence, regional spread, and distant metastasis has been negative at a 6-month follow-up. Ultimately, we report the first case of a GLI1-amplified mesenchymal neoplasm of the intraconal orbit managed with gross total resection via a combined approach followed by adjuvant radiation therapy.
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BACKGROUND: miR-346 was identified as an activator of Androgen Receptor (AR) signalling that associates with DNA damage response (DDR)-linked transcripts in prostate cancer (PC). We sought to delineate the impact of miR-346 on DNA damage, and its potential as a therapeutic agent. METHODS: RNA-IP, RNA-seq, RNA-ISH, DNA fibre assays, in vivo xenograft studies and bioinformatics approaches were used alongside a novel method for amplification-free, single nucleotide-resolution genome-wide mapping of DNA breaks (INDUCE-seq). RESULTS: miR-346 induces rapid and extensive DNA damage in PC cells - the first report of microRNA-induced DNA damage. Mechanistically, this is achieved through transcriptional hyperactivation, R-loop formation and replication stress, leading to checkpoint activation and cell cycle arrest. miR-346 also interacts with genome-protective lncRNA NORAD to disrupt its interaction with PUM2, leading to PUM2 stabilisation and its increased turnover of DNA damage response (DDR) transcripts. Confirming clinical relevance, NORAD expression and activity strongly correlate with poor PC clinical outcomes and increased DDR in biopsy RNA-seq studies. In contrast, miR-346 is associated with improved PC survival. INDUCE-seq reveals that miR-346-induced DSBs occur preferentially at binding sites of the most highly-transcriptionally active transcription factors in PC cells, including c-Myc, FOXA1, HOXB13, NKX3.1, and importantly, AR, resulting in target transcript downregulation. Further, RNA-seq reveals widespread miR-346 and shNORAD dysregulation of DNA damage, replication and cell cycle processes. NORAD drives target-directed miR decay (TDMD) of miR-346 as a novel genome protection mechanism: NORAD silencing increases mature miR-346 levels by several thousand-fold, and WT but not TDMD-mutant NORAD rescues miR-346-induced DNA damage. Importantly, miR-346 sensitises PC cells to DNA-damaging drugs including PARP inhibitor and chemotherapy, and induces tumour regression as a monotherapy in vivo, indicating that targeting miR-346:NORAD balance is a valid therapeutic strategy. CONCLUSIONS: A balancing act between miR-346 and NORAD regulates DNA damage and repair in PC. miR-346 may be particularly effective as a therapeutic in the context of decreased NORAD observed in advanced PC, and in transcriptionally-hyperactive cancer cells.
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MicroARNs , Neoplasias de la Próstata , ARN Largo no Codificante , Ciclo Celular , Daño del ADN , Humanos , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Próstata/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/genética , Factores de Transcripción/genéticaRESUMEN
BACKGROUND: The use of rifamycin antibiotics for TB prevention carries a risk of detrimental drug-drug interactions with concomitantly used ART. OBJECTIVES: To evaluate the interaction of the antiretroviral drug nevirapine in combination with 4 weeks of daily rifapentine and isoniazid for TB prevention in people living with HIV. METHODS: Participants were individuals enrolled in the BRIEF-TB study receiving nevirapine and randomized to the rifapentine/isoniazid arm of the study. Participants provided sparse pharmacokinetic (PK) sampling at baseline and weeks 2 and 4 for trough nevirapine determination. Nevirapine apparent oral clearance (CL/F) was estimated and the geometric mean ratio (GMR) of CL/F prior to and during rifapentine/isoniazid was calculated. RESULTS: Seventy-eight participants had evaluable PK data: 61 (78%) female, 51 (65%) black non-Hispanic and median (range) age of 40 (13-66) years. Median (IQR) nevirapine trough concentrations were: week 0, 7322 (5266-9302) ng/mL; week 2, 5537 (3552-8462) ng/mL; and week 4, 5388 (3516-8243) ng/mL. Sixty out of 78 participants (77%) had nevirapine concentrations ≥3000 ng/mL at both week 2 and 4. Median (IQR) nevirapine CL/F values were: week 0 pre-rifapentine/isoniazid, 2.03 (1.58-2.58) L/h; and during rifapentine/isoniazid, 2.62 (1.81-3.42) L/h. The GMR (90% CI) for nevirapine CL/F was 1.30 (1.26-1.33). CONCLUSIONS: The CL/F of nevirapine significantly increased with concomitant rifapentine/isoniazid. The decrease in nevirapine trough concentrations during rifapentine/isoniazid therapy suggests induction of nevirapine metabolism, consistent with known rifapentine effects. The magnitude of this drug-drug interaction suggests daily rifapentine/isoniazid for TB prevention should not be co-administered with nevirapine-containing ART.
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Fármacos Anti-VIH , Infecciones por VIH , Adolescente , Adulto , Anciano , Fármacos Anti-VIH/uso terapéutico , Antituberculosos/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Isoniazida/uso terapéutico , Masculino , Persona de Mediana Edad , Nevirapina/uso terapéutico , Rifampin/análogos & derivados , Adulto JovenRESUMEN
BACKGROUND: Breast cancer (BC) incidence in Australian women aged 45 to 64 years ('middle-aged') has tripled in the past 50 years, along with increasing alcohol consumption and obesity in middle-age women. Alcohol and obesity have been individually associated with BC but little is known about how these factors might interact. Chronic psychological stress has been associated with, but not causally linked to, BC. Here, alcohol could represent the 'missing link' - reflecting self-medication. Using an exploratory cross-sectional design, we investigated inter-correlations of alcohol intake and overweight/obesity and their association with BC incidence in middle-aged women. We also explored the role of stress and various lifestyle factors in these relationships. METHODS: We analysed population data on BC incidence, alcohol consumption, overweight/obesity, and psychological stress. A case control study was conducted using an online survey. Cases (n = 80) were diagnosed with BC and controls (n = 235) were women in the same age range with no BC history. Participants reported lifestyle data (including alcohol consumption, weight history) over consecutive 10-year life periods. Data were analysed using a range of bivariate and multivariate techniques including correlation matrices, multivariate binomial regressions and multilevel logistic regression. RESULTS: Ecological inter-correlations were found between BC and alcohol consumption and between BC and obesity but not between other variables in the matrix. Strong pairwise correlations were found between stress and alcohol and between stress and obesity. BMI tended to be higher in cases relative to controls across reported life history. Alcohol consumption was not associated with case-control status. Few correlations were found between lifestyle factors and stress, although smoking and alcohol consumption were correlated in some periods. Obesity occurring during the ages of 31 to 40 years emerged as an independent predictor of BC (OR 3.5 95% CI: 1.3-9.4). CONCLUSIONS: This study provides ecological evidence correlating obesity and alcohol consumption with BC incidence. Case-control findings suggest lifetime BMI may be important with particular risk associated with obesity prior to 40 years of age. Stress was ecologically linked to alcohol and obesity but not to BC incidence and was differentially correlated with alcohol and smoking among cases and controls. Our findings support prevention efforts targeting weight in women below 40 years of age and, potentially, lifelong alcohol consumption to reduce BC risk in middle-aged women.
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Consumo de Bebidas Alcohólicas/epidemiología , Neoplasias de la Mama/epidemiología , Obesidad/epidemiología , Australia/epidemiología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Incidencia , Estilo de Vida , Persona de Mediana Edad , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
INTRODUCTION: Serious health complications associated with excessive weight have been documented for pregnant women and their babies during pregnancy, birth and beyond. Whilst research has focused on identifying particular foods that can be either detrimental or essential for the developing baby, pregnant women's food choices are likely determined by broader considerations. This study examined social influences as represented in reports of descriptive and injunctive social norms related to healthy eating during pregnancy, and individual differences in mindfulness while eating, as important potential correlates of pregnant women's self-reported diet. METHODS: Pregnant women (N = 139) completed a questionnaire that measured self-reported consumption of healthy and unhealthy foods, descriptive and injunctive norms related to healthy eating during pregnancy and the Mindful Eating Questionnaire (MEQ). Hierarchical multiple regressions were conducted to assess the extent to which norms and mindful eating accounted for variance in consumption of both foods. RESULTS: No significant associations were observed between perceived social norms related to diet during pregnancy and self-reported dietary behaviour. Mindful eating was found to play a role in pregnant women's eating behaviour, with the awareness subscale of the MEQ significantly associated with healthy eating and the emotional subscale associated with unhealthy eating. Age was also associated with consumption of unhealthy foods; younger pregnant women reported consuming more unhealthy snacks and fast food meals. CONCLUSIONS: The associations between mindful eating and dietary behaviour suggests that improving mindfulness related to food consumption before and during pregnancy may provide a strategy to address excessive gestational weight gain.
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Conducta de Elección , Dieta/psicología , Preferencias Alimentarias/psicología , Atención Plena , Complicaciones del Embarazo , Normas Sociales , Adulto , Factores de Edad , Concienciación , Dieta Saludable , Ingestión de Alimentos/psicología , Emociones , Comida Rápida , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Complicaciones del Embarazo/etiología , Complicaciones del Embarazo/prevención & control , Mujeres Embarazadas/psicología , Autoinforme , Bocadillos , Encuestas y Cuestionarios , Aumento de Peso , Adulto JovenRESUMEN
Patients with antiphospholipid syndrome (APS) produce antiphospholipid antibodies (aPL) and develop vascular thrombosis that may occur in large or small vessels in the arterial or venous beds. On the other hand, many individuals produce aPL and yet never develop thrombotic events. Toll-like receptor 4 (TLR4) appears to be necessary for aPL-mediated prothrombotic effects in venous and microvascular models of thrombosis, but its role in arterial thrombosis has not been studied. Here, we propose that aPL alone are insufficient to cause thrombotic events in an arterial model of APS, and that a concomitant trigger of innate immunity (e.g. TLR4 activation) is required. We show specifically that anti-ß2-glycoprotein I (anti-ß2GPI) antibodies, a subset of aPL, accelerated thrombus formation in C57BL/6 wild-type, but not TLR4-deficient, mice in a ferric chloride-induced carotid artery injury model. These aPL bound to arterial and venous endothelial cells, particularly in the presence of ß2GPI, and to human TLR4 by enzyme-linked immunoassay. Arterial endothelium from aPL-treated mice had enhanced leukocyte adhesion, compared to control IgG-treated mice. In addition, aPL treatment of mice enhanced expression of tissue factor (TF) in leukocytes induced by the TLR4 ligand lipopolysaccharide (LPS). aPL also enhanced LPS-induced TF expression in human leukocytes in vitro. Our findings support a mechanism in which aPL enhance TF expression by leukocytes, as well as augment adhesion of leukocytes to the arterial endothelium. The activation of TLR4 in aPL-positive individuals may be required to trigger thrombotic events.
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Anticuerpos Antifosfolípidos/inmunología , Trombosis/inmunología , Receptor Toll-Like 4/inmunología , Animales , Anticuerpos Monoclonales de Origen Murino/inmunología , Síndrome Antifosfolípido/inmunología , Adhesión Celular/fisiología , Endotelio Vascular/metabolismo , Femenino , Humanos , Inmunidad Innata , Leucocitos/inmunología , Lipopolisacáridos/inmunología , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Tromboplastina/inmunología , beta 2 Glicoproteína I/antagonistas & inhibidores , beta 2 Glicoproteína I/inmunologíaRESUMEN
The International Knockout Mouse Consortium (IKMC) developed high throughput gene trapping and gene targeting pipelines that produced mostly conditional mutations of more than 18,500 genes in C57BL/6N mouse embryonic stem (ES) cells which have been archived and are freely available to the research community as a frozen resource. From this unprecedented resource more than 6,000 mutant mouse strains have been produced by the IKMC and mostly the International Mouse Phenotyping Consortium (IMPC). In addition, a cre-driver resource was established including 250 inducible cre-driver mouse strains in a C57BL/6 background. Complementing the cre-driver resource, a collection of comprising 27 cre-driver rAAVs has also been produced. The resources can be easily accessed at the IKMC/IMPC web portal (www.mousephenotype.org). The IKMC/IMPC resource is a standardized reference library of mouse models with defined genetic backgrounds that enables the analysis of gene-disease associations in mice of different genetic makeup and should therefore have a major impact on biomedical research.
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OBJECTIVES: Tenofovir disoproxil fumarate (TDF) is increasingly used in the highly active antiretroviral therapy (HAART) regimens of pregnant women, but limited data exist on the pregnancy pharmacokinetics of chronically dosed TDF. This study described tenofovir pharmacokinetics during pregnancy and postpartum. METHODS: International Maternal Pediatric and Adolescent AIDS Clinical Trials (IMPAACT) P1026s is a prospective, nonblinded pharmacokinetic study of HIV-infected pregnant women that included a cohort receiving 300 mg TDF once daily. Steady-state 24-hour pharmacokinetic profiles were measured at the second and third trimesters, postpartum, and in maternal and umbilical cord samples collected at delivery. Tenofovir was measured by liquid chromatography-mass spectrometry (LC-MS). The target area under the concentration versus time curve from time 0 to 24 h post dose (AUC) was ≥ 1.99 µg h/mL (nonpregnant historical control 10th percentile). RESULTS: The median tenofovir AUC was decreased during the second (1.9 µg h/mL) and third (2.4 µg h/mL; P = 0.005) trimesters versus postpartum (3.0 µg h/mL). Tenofovir AUC exceeded the target for two of four women (50%) in the second trimester, 27 of 37 women [73%; 95% confidence interval (CI) 56%, 86%] in the third trimester, and 27 of 32 women (84%; 95% CI 67%, 95%) postpartum (P > 0.05). Median second/third-trimester troughs were lower (39/54 ng/mL) than postpartum (61 ng/mL). Median third-trimester weight was greater for subjects below the target AUC versus those above the target (97.9 versus 74.2 kg, respectively; P = 0.006). The median ratio of cord blood to maternal concentrations was 0.88. No infants were HIV infected. CONCLUSIONS: This study found lower tenofovir AUC and troughs during pregnancy. Transplacental passage with chronic TDF use during pregnancy was high. Standard TDF doses appear to be appropriate for most HIV-infected pregnant women but therapeutic drug monitoring with dose adjustment should be considered in pregnant women with high weight (> 90 kg) or inadequate HIV RNA response.
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Fármacos Anti-VIH/farmacocinética , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/farmacocinética , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Tenofovir/farmacocinética , Adolescente , Adulto , Fármacos Anti-VIH/uso terapéutico , Área Bajo la Curva , Femenino , Infecciones por VIH/metabolismo , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1 , Humanos , Masculino , Periodo Posparto , Embarazo , Complicaciones Infecciosas del Embarazo/metabolismo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Tenofovir/uso terapéutico , Adulto JovenRESUMEN
The human gut symbiont Bacteroides fragilis has a general protein O-glycosylation system in which numerous extracytoplasmic proteins are glycosylated at a three amino acid motif. In B. fragilis, protein glycosylation is a fundamental and essential property as mutants with protein glycosylation defects have impaired growth and are unable to competitively colonize the mammalian intestine. In this study, we analysed the phenotype of B. fragilis mutants with defective protein glycosylation and found that the glycan added to proteins is comprised of a core glycan and an outer glycan. The genetic region encoding proteins for the synthesis of the outer glycan is conserved within a Bacteroides species but divergent between species. Unlike the outer glycan, an antiserum raised to the core glycan reacted with all Bacteroidetes species tested, from all four classes of the phylum. We found that diverse Bacteroidetes species synthesize numerous glycoproteins and glycosylate proteins at the same three amino acid motif. The wide-spread conservation of this protein glycosylation system within the phylum suggests that this system of post-translational protein modification evolved early, before the divergence of the four classes of Bacteroidetes, and has been maintained due to its physiological importance to the diverse species of this phylum.
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Proteínas Bacterianas/metabolismo , Bacteroidetes/genética , Bacteroidetes/metabolismo , Glicoproteínas/metabolismo , Polisacáridos/metabolismo , Secuencia Conservada , Genes Bacterianos , Glicosilación , Redes y Vías MetabólicasRESUMEN
BACKGROUND: There is solid evidence of the long term efficacy of deep brain stimulation of the globus pallidus pars interna in the treatment of generalised dystonia. However there are conflicting reports concerning whether certain subgroups gain more benefit from treatment than others. We analysed the results of a series of 60 cases to evaluate the effects of previously proposed prognostic factors including dystonia aetiology, dystonia phenotype, age at onset of dystonia, and duration of dystonia prior to treatment. METHODS: 60 patients with medically intractable primary or secondary generalised dystonia were treated with deep brain stimulation of the globus pallidus pars interna during the period 1999-2010 at the Department of Neurosurgery in Oxford, UK. Patients were assessed using the Burke-Fahn-Marsden (BFM) Dystonia Rating Scale prior to surgery, 6 months after implantation and thereafter at 1 year, 2 years and 5 years follow-up. RESULTS: The group showed mean improvements in the BFM severity and disability scores of 43% and 27%, respectively, by 6 months, and this was sustained. The results in 11 patients with DYT gene mutations were significantly better than in non-genetic primary cases. The results in 12 patients with secondary dystonia were not as good as those seen in non-genetic primary cases but there remained a significant beneficial effect. Age of onset of dystonia, duration of disease prior to surgery, and myoclonic versus torsional disease phenotype had no significant effect on outcome. CONCLUSIONS: The aetiology of dystonia was the sole factor predicting a better or poorer outcome from globus pallidus pars interna stimulation in this series of patients with generalised dystonia. However even the secondary cases that responded the least well had a substantial reduction in BFM scores compared with preoperative clinical assessments, and these patients should still be considered for deep brain stimulation.
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Estimulación Encefálica Profunda , Distonía/terapia , Adolescente , Adulto , Edad de Inicio , Anciano , Niño , Estimulación Encefálica Profunda/efectos adversos , Distonía/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto JovenRESUMEN
The international literature shows that the demography of cystic fibrosis (CF) is changing, with patients increasingly surviving into adulthood. As they age, patients with CF become more susceptible to specific non-pulmonary chronic diseases. In this study, adult data from the CF Registry of Ireland (CFRI) was used to determine the prevalence and associated features of these diseases. 104 (25.7%) adults had diabetes versus 13 (2.9%) children (p < 0.001). Liver disease was present in 47 (11.6%) adults and 26 (5.7%) children (p = 0.002). 173 (42.7%) adults had bone disease versus 25 (5.5%) children (p < 0.001). Adults with one non-pulmonary chronic disease, for example liver disease, were more likely to have another (p = 0.002), those with diabetes and bone disease had a higher number of hospital admissions in the last 12 months (p < 0.001 for both) and higher rates of depression (p = 0.046 and p = 0.049, respectively). These results highlight a number of challenges for the Irish healthcare system.
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Enfermedades Óseas/epidemiología , Fibrosis Quística/epidemiología , Diabetes Mellitus/epidemiología , Hepatopatías/epidemiología , Adolescente , Adulto , Factores de Edad , Enfermedades Óseas/genética , Enfermedad Crónica , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Diabetes Mellitus/genética , Femenino , Genotipo , Humanos , Irlanda/epidemiología , Hepatopatías/genética , Masculino , Persona de Mediana Edad , Prevalencia , Sistema de Registros , Adulto JovenRESUMEN
Breast cancer (BC) is the most diagnosed cancer in women worldwide. In estrogen receptor (ER)-positive disease, anti-estrogens and aromatase inhibitors (AI) improve patient survival; however, many patients develop resistance. Dysregulation of apoptosis is a common resistance mechanism; thus, agents that can reinstate the activity of apoptotic pathways represent promising therapeutics for advanced drug-resistant disease. Emerging targets in this scenario include microRNAs (miRs). To identify miRs modulating apoptosis in drug-responsive and -resistant BC, a high-throughput miR inhibitor screen was performed, followed by high-content screening microscopy for apoptotic markers. Validation demonstrated that miR-361-3p inhibitor significantly increases early apoptosis and reduces proliferation of drug-responsive (MCF7), plus AI-/antiestrogen-resistant derivatives (LTED, TamR, FulvR), and ER- cells (MDA-MB-231). Importantly, proliferation-inhibitory effects were observed in vivo in a xenograft model, indicating the potential clinical application of miR-361-3p inhibition. RNA-seq of tumour xenografts identified FANCA as a direct miR-361-3p target, and validation suggested miR-361-3p inhibitor effects might be mediated in part through FANCA modulation. Moreover, miR-361-3p inhibition resulted in p53-mediated G1 cell cycle arrest through activation of p21 and reduced BC invasion. Analysis of publicly available datasets showed miR-361-3p expression is significantly higher in primary breast tumours vspaired normal tissue and is associated with decreased overall survival. In addition, miR-361-3p inhibitor treatment of BC patient explants decreased levels of miR-361-3p and proliferation marker, Ki67. Finally, miR-361-3p inhibitor showed synergistic effects on BC growth when combined with PARP inhibitor, Olaparib. Together, these studies identify miR-361-3p inhibitor as a potential new treatment for drug-responsive and -resistant advanced BC.
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Neoplasias de la Mama , MicroARNs , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Resistencia a Antineoplásicos/genética , MicroARNs/genética , MicroARNs/metabolismo , Antagonistas de Estrógenos/farmacología , Inhibidores de la Aromatasa/farmacología , Inhibidores de la Aromatasa/uso terapéutico , Apoptosis/genética , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Línea Celular TumoralRESUMEN
Among bacterial species demonstrated to have protein O-glycosylation systems, that of Bacteroides fragilis and related species is unique in that extracytoplasmic proteins are glycosylated at serine or threonine residues within the specific three-amino acid motif D(S/T)(A/I/L/M/T/V). This feature allows for computational analysis of the proteome to identify candidate glycoproteins. With the criteria of a signal peptidase I or II cleavage site or a predicted transmembrane-spanning region and the presence of at least one glycosylation motif, we identified 1021 candidate glycoproteins of B. fragilis. In addition to the eight glycoproteins identified previously, we confirmed that another 12 candidate glycoproteins are in fact glycosylated. These included four glycoproteins that are predicted to localize to the inner membrane, a compartment not previously shown to include glycosylated proteins. In addition, we show that four proteins involved in cell division and chromosomal segregation, two of which are encoded by candidate essential genes, are glycosylated. To date, we have not identified any extracytoplasmic proteins containing a glycosylation motif that are not glycosylated. Therefore, based on the list of 1021 candidate glycoproteins, it is likely that hundreds of proteins, comprising more than half of the extracytoplasmic proteins of B. fragilis, are glycosylated. Site-directed mutagenesis of several glycoproteins demonstrated that all are glycosylated at the identified glycosylation motif. By engineering glycosylation motifs into a naturally unglycosylated protein, we are able to bring about site-specific glycosylation at the engineered sites, suggesting that this glycosylation system may have applications for glycoengineering.
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Bacteroides fragilis/química , Biología Computacional/métodos , Secuencia Conservada , Glicosilación , Proteoma , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Ácido Aspártico Endopeptidasas , Proteínas Bacterianas , Bacteroides fragilis/metabolismo , Sitios de Unión , Proteínas de la Membrana , Mutagénesis Sitio-Dirigida , Serina EndopeptidasasRESUMEN
BACKGROUND: The neutrophil lymphocyte ratio (NLR) has prognostic value in patients with a variety of cancers. Many chemotherapeutic trial databases hold information on white cell and neutrophil counts only. The aim of the present study was to compare the prognostic value of the NLR with a derived score (dNLR), composed of white cell and neutrophil counts. METHODS: Patients (n=27,031) who were sampled incidentally between 2000 and 2007 for neutrophil, lymphocyte and white cell counts, and also had a diagnosis of cancer (Scottish Cancer Registry), were identified. Of this group, 12,118 patients who had been sampled within 2 years of their cancer diagnosis were studied. RESULTS: On follow-up, there were 7366 deaths, of which 6198 (84%) were cancer deaths. The median time from blood sampling to diagnosis was 2.1 months. The area under the receiver-operating characteristic (ROC) curve for cancer-specific survival was 0.650 for the NLR and 0.640 for the dNLR. The NLR and dNLR were independently associated with survival in all cancers studied (all P<0.001). The optimal thresholds, on the basis of hazard ratios and area under the curve, were 4 : 1 for the NLR and 2 : 1 for the dNLR. CONCLUSION: The results of the present study show that the dNLR has similar prognostic value to the NLR. Therefore, the universally available dNLR is to be commended for use in the risk stratification of patients undergoing chemotherapy.
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Recuento de Leucocitos , Recuento de Linfocitos , Neoplasias/sangre , Neutrófilos/inmunología , Anciano , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , PronósticoRESUMEN
OBJECTIVE: To report outcomes in a recent series of pregnancies in women with pulmonary hypertension (PH). DESIGN: Retrospective case note review. SETTING: Tertiary referral unit (Chelsea and Westminster and Royal Brompton Hospitals). SAMPLE: Twelve pregnancies in nine women with PH between 1995 and 2010. METHODS: Multidisciplinary review of case records. MAIN OUTCOME MEASURES: Maternal and neonatal mortality and morbidity. RESULTS: There were two maternal deaths (1995 and 1998), one related to pre-eclampsia and one to arrhythmia. Maternal morbidity included postpartum haemorrhage (five cases), and one post-caesarean evacuation of a wound haematoma. There were no perinatal deaths, nine live births and three first-trimester miscarriages. Mean birthweight was 2197 g, mean gestational age was 34 weeks (range 26-39), and mean birthweight centile was 36 (range 5-60). Five babies required admission to the neonatal intensive care unit, but were all eventually discharged home. All women were delivered by caesarean section (seven elective and two emergency deliveries), under general anaesthetic except for one emergency and one elective caesarean performed under regional block. CONCLUSIONS: Maternal and fetal outcomes for women with PH may be improving. However, the risk of maternal mortality remains significant, so that early and effective counselling about contraceptive options and pregnancy risks should continue to play a major role in the management of such women when they reach reproductive maturity.
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Hipertensión Pulmonar/complicaciones , Complicaciones del Embarazo/terapia , Resultado del Embarazo , Adulto , Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/mortalidad , Femenino , Humanos , Mortalidad Materna , Preeclampsia/mortalidad , Embarazo , Estudios Retrospectivos , Adulto JovenRESUMEN
The ICH E9(R1) addendum on Estimands and Sensitivity Analyses in Clinical Trials has introduced a new estimand framework for the design, conduct, analysis, and interpretation of clinical trials. We share Pharmaceutical Industry experiences of implementing the estimand framework in the first two years since the final guidance became available with key lessons learned and highlight what else needs to be done to continue the journey in embedding the estimand framework in clinical trials. Emerging best practices and points to consider on strategies for implementing a new estimand thinking process are provided. Whilst much of the focus of implementing ICH E9(R1) to date has been on defining estimands, we highlight some of the important aspects relating to the choice of statistical analysis methods and sensitivity analyses to ensure estimands can be estimated robustly with minimal bias. In particular, we discuss the implications if complete follow-up is not possible when the treatment policy strategy is being used to handle intercurrent events. ICH E9(R1) was introduced just before the start of the COVID-19 pandemic, but a positive outcome from the pandemic has been an acceleration in the adoption of the estimand framework, including differentiating intercurrent events related or not related to the pandemic. In summary, much has been learned on the estimand journey and continued sharing of case studies will help to further advance the understanding and increase awareness across all clinical researchers of the estimand framework.
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Tratamiento Farmacológico de COVID-19 , Medicina , Interpretación Estadística de Datos , Humanos , Pandemias , Proyectos de InvestigaciónRESUMEN
Xylose is rarely described as a component of bacterial glycans. UDP-xylose is the nucleotide-activated form necessary for incorporation of xylose into glycans and is synthesized by the decarboxylation of UDP-glucuronic acid (UDP-GlcA). Enzymes with UDP-GlcA decarboxylase activity include those that lead to the formation of UDP-xylose as the end product (Uxs type) and those synthesizing UDP-xylose as an intermediate (ArnA and RsU4kpxs types). In this report, we identify and confirm the activities of two Uxs-type UDP-GlcA decarboxylases of Bacteroides fragilis, designated BfUxs1 and BfUxs2. Bfuxs1 is located in a conserved region of the B. fragilis genome, whereas Bfuxs2 is in the heterogeneous capsular polysaccharide F (PSF) biosynthesis locus. Deletion of either gene separately does not result in the loss of a detectable phenotype, but deletion of both genes abrogates PSF synthesis, strongly suggesting that they are functional paralogs and that the B. fragilis NCTC 9343 PSF repeat unit contains xylose. UDP-GlcA decarboxylases are often annotated incorrectly as NAD-dependent epimerases/dehydratases; therefore, their prevalence in bacteria is underappreciated. Using available structural and mutational data, we devised a sequence pattern to detect bacterial genes encoding UDP-GlcA decarboxylase activity. We identified 826 predicted UDP-GlcA decarboxylase enzymes in diverse bacterial species, with the ArnA and RsU4kpxs types confined largely to proteobacterial species. These data suggest that xylose, or a monosaccharide requiring a UDP-xylose intermediate, is more prevalent in bacterial glycans than previously appreciated. Genes encoding BfUxs1-like enzymes are highly conserved in Bacteroides species, indicating that these abundant intestinal microbes may synthesize a conserved xylose-containing glycan.
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Bacteroides fragilis/enzimología , Carboxiliasas/metabolismo , Bacteroides fragilis/metabolismo , Western Blotting , Carboxiliasas/genética , Cromatografía Líquida de Alta Presión , Biología Computacional , Electroforesis en Gel de Poliacrilamida , Genoma Bacteriano/genética , Polisacáridos Bacterianos/metabolismo , Xilosa/metabolismoRESUMEN
PPARgamma is a nuclear receptor that has a dominant regulatory role in differentiation of cells of the adipose lineage, and has recently been shown to be expressed in the colon. We show here that PPARgamma is expressed at high levels in both well- and poorly-differentiated adenocarcinomas, in normal colonic mucosa and in human colon cancer cell lines. Ligand activation of this receptor in colon cancer cells causes a considerable reduction in linear and clonogenic growth, increased expression of carcinoembryonic antigen and the reversal of many gene expression events specifically associated with colon cancer. Transplantable tumors derived from human colon cancer cells show a significant reduction of growth when mice are treated with troglitazone, a PPARgamma ligand. These results indicate that the growth and differentiation of colon cancer cells can be modulated through PPARgamma.