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Transcriptional regulation in metazoans occurs through long-range genomic contacts between enhancers and promoters, and most genes are transcribed in episodic "bursts" of RNA synthesis. To understand the relationship between these two phenomena and the dynamic regulation of genes in response to upstream signals, we describe the use of live-cell RNA imaging coupled with Hi-C measurements and dissect the endogenous regulation of the estrogen-responsive TFF1 gene. Although TFF1 is highly induced, we observe short active periods and variable inactive periods ranging from minutes to days. The heterogeneity in inactive times gives rise to the widely observed "noise" in human gene expression and explains the distribution of protein levels in human tissue. We derive a mathematical model of regulation that relates transcription, chromosome structure, and the cell's ability to sense changes in estrogen and predicts that hypervariability is largely dynamic and does not reflect a stable biological state.
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Regulação da Expressão Gênica/fisiologia , Expressão Gênica/fisiologia , Transcrição Gênica/fisiologia , Receptor alfa de Estrogênio/metabolismo , Estrogênios , Expressão Gênica/genética , Humanos , Modelos Teóricos , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/metabolismo , Análise de Célula Única/métodos , Transcrição Gênica/genética , Ativação Transcricional/fisiologia , Fator Trefoil-1/genéticaRESUMO
The hormone-stimulated glucocorticoid receptor (GR) modulates transcription by interacting with thousands of enhancers and GR binding sites (GBSs) throughout the genome. Here, we examined the effects of GR binding on enhancer dynamics and investigated the contributions of individual GBSs to the hormone response. Hormone treatment resulted in genome-wide reorganization of the enhancer landscape in breast cancer cells. Upstream of the DDIT4 oncogene, GR bound to four sites constituting a hormone-dependent super enhancer. Three GBSs were required as hormone-dependent enhancers that differentially promoted histone acetylation, transcription frequency, and burst size. Conversely, the fourth site suppressed transcription and hormone treatment alleviated this suppression. GR binding within the super enhancer promoted a loop-switching mechanism that allowed interaction of the DDIT4 TSS with the active GBSs. The unique functions of each GR binding site contribute to hormone-induced transcriptional heterogeneity and demonstrate the potential for targeted modulation of oncogene expression.
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Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Dexametasona/farmacologia , Elementos Facilitadores Genéticos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Receptores de Glucocorticoides/agonistas , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais , Fatores de Transcrição/genéticaRESUMO
Butterfly color patterns provide visible and biodiverse phenotypic readouts of the patterning processes. Although the secreted ligand WntA has been shown to instruct the color pattern formation in butterflies, its mode of reception remains elusive. Butterfly genomes encode four homologs of the Frizzled-family of Wnt receptors. Here, we show that CRISPR mosaic knockouts of frizzled2 (fz2) phenocopy the color pattern effects of WntA loss of function in multiple nymphalids. Whereas WntA mosaic clones result in intermediate patterns of reduced size, fz2 clones are cell-autonomous, consistent with a morphogen function. Shifts in expression of WntA and fz2 in WntA crispant pupae show that they are under positive and negative feedback, respectively. Fz1 is required for Wnt-independent planar cell polarity in the wing epithelium. Fz3 and Fz4 show phenotypes consistent with Wnt competitive-antagonist functions in vein formation (Fz3 and Fz4), wing margin specification (Fz3), and color patterning in the Discalis and Marginal Band Systems (Fz4). Overall, these data show that the WntA/Frizzled2 morphogen-receptor pair forms a signaling axis that instructs butterfly color patterning and shed light on the functional diversity of insect Frizzled receptors.
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Borboletas , Pigmentação , Animais , Pigmentação/genética , Borboletas/genética , Borboletas/metabolismo , Transdução de Sinais/genética , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Asas de Animais/metabolismoRESUMO
Extra-intestinal pathogenic Escherichia coli (ExPEC) belong to a critical priority group of antibiotic resistant pathogens. ExPEC establish gut reservoirs that seed infection of the urinary tract and bloodstream, but the mechanisms of gut colonisation remain to be properly understood. Ucl fimbriae are attachment organelles that facilitate ExPEC adherence. Here, we investigated cellular receptors for Ucl fimbriae and Ucl expression to define molecular mechanisms of Ucl-mediated ExPEC colonisation of the gut. We demonstrate differential expression of Ucl fimbriae in ExPEC sequence types associated with disseminated infection. Genome editing of strains from two common sequence types, F11 (ST127) and UTI89 (ST95), identified a single nucleotide polymorphism in the ucl promoter that changes fimbriae expression via activation by the global stress-response regulator OxyR, leading to altered gut colonisation. Structure-function analysis of the Ucl fimbriae tip-adhesin (UclD) identified high-affinity glycan receptor targets, with highest affinity for sialyllacto-N-fucopentose VI, a structure likely to be expressed on the gut epithelium. Comparison of the UclD adhesin to the homologous UcaD tip-adhesin from Proteus mirabilis revealed that although they possess a similar tertiary structure, apart from lacto-N-fucopentose VI that bound to both adhesins at low-micromolar affinity, they recognize different fucose- and glucose-containing oligosaccharides. Competitive surface plasmon resonance analysis together with co-structural investigation of UcaD in complex with monosaccharides revealed a broad-specificity glycan binding pocket shared between UcaD and UclD that could accommodate these interactions. Overall, our study describes a mechanism of adaptation that augments establishment of an ExPEC gut reservoir to seed disseminated infections, providing a pathway for the development of targeted anti-adhesion therapeutics.
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Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Adesinas Bacterianas/metabolismo , Adesinas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Infecções por Escherichia coli/metabolismo , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli Extraintestinal Patogênica/metabolismo , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Humanos , Enteropatias , Polissacarídeos/metabolismoRESUMO
In multiple myeloma (MM), advancements in treatments and toxicity management have enhanced survival rates. This, coupled with shifting age demographics in MM, necessitates an updated understanding of infection risks in MM patients compared to the general population. Using Swedish population-based registries, we investigated the incidence of infections in 8,672 Swedish symptomatic MM patients diagnosed 2008-2021 and 34,561 matched controls. Overall, MM patients had a 5-fold risk (hazard ratio (HR) = 5.30; 95%, Confidence Interval = CI 5.14-5.47) of developing any clinically significant infection compared to matched controls. Bacterial infections represented a 5-fold (HR 4.88; CI 4.70-5.07) increased risk, viral and fungal infections 7-fold compared to controls. The 1st year after MM diagnosis the risk of infections compared to controls was 7 -fold (HR 6.95; CI 6.61-7.30) and remained elevated up to 5 years after the myeloma diagnosis. The risk of infection compared to controls remained 5-fold in MM patients with follow-up till 2022. Preceding MM diagnosis, the risk compared to matched controls was significantly increased up to four years before MM diagnosis (HR1.16; CI 1.05-1.28). Among MM patients, 8% had died within 2 months of diagnosis and infection contributed to 32% of all deaths. After 1 year, 20% MM patients had died, and infection-related mortality was 27%. Our data constitute the largest population-based study to date on the risk of infections compared to the normal population in the era of modern MM therapies and confirms that infections still represent a major threat to patients and underscores importance of preventive strategies.
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ABSTRACT: Fractures of the hyoid bone, particularly the greater horns, and thyroid cartilage (superior horns) are known to be associated with hanging deaths. Depending on the literature, the frequency of these fractures varies from 0% to 83%. The mechanism underlying these fractures is believed to be direct compression or indirect traction from the ligature. The relationship of these structures with the cervical spine cannot be visualized with traditional internal examination, due to obstruction by surrounding soft tissue. Postmortem computed tomography scan offers an unobscured view of the relationship of the laryngohyoid structures with the cervical spine.We aim to illustrate the phenomenon of displacement of the laryngohyoid structures associated with fractures of the horns. In our case reports, the laryngohyoid structures were displaced, not only superiorly and posteriorly, but also in 2 of the cases, by tilting, when the suspension point was at the posterior or posterolateral aspect of the neck. This displacement had caused the greater horns of the hyoid bone and superior horns of the thyroid cartilage to be approximated against the cervical spine, particularly the transverse processes. We believe that, in these circumstances, the fractures were caused by pressure of the horns of the laryngohyoid structures against the cervical spine.
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Asfixia , Fraturas Ósseas , Osso Hioide , Cartilagem Tireóidea , Tomografia Computadorizada por Raios X , Humanos , Osso Hioide/lesões , Osso Hioide/patologia , Osso Hioide/diagnóstico por imagem , Asfixia/patologia , Asfixia/etiologia , Cartilagem Tireóidea/lesões , Cartilagem Tireóidea/patologia , Cartilagem Tireóidea/diagnóstico por imagem , Masculino , Fraturas Ósseas/patologia , Fraturas Ósseas/diagnóstico por imagem , Lesões do Pescoço/patologia , Lesões do Pescoço/diagnóstico por imagem , Suicídio Consumado , Pessoa de Meia-Idade , Adulto , Feminino , Vértebras Cervicais/lesões , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologiaRESUMO
Neisseria gonorrhoeae has developed resistance to all previous antibiotics used for treatment. This highlights a crucial need for novel antimicrobials to treat gonococcal infections. We previously showed that carbamazepine (Cz), one of the most commonly prescribed antiepileptic drugs, can block the interaction between gonococcal pili and the I-domain region of human complement receptor 3 (CR3)-an interaction that is vital for infection of the female cervix. We also show that Cz can completely clear an established N. gonorrhoeae infection of primary human cervical cells. In this study, we quantified Cz in serum, saliva, and vaginal fluid collected from 16 women who were, or were not, regularly taking Cz. We detected Cz in lower reproductive tract mucosal secretions in the test group (women taking Cz) at potentially therapeutic levels using a competitive ELISA. Furthermore, we found that Cz concentrations present in vaginal fluid from women taking this drug were sufficient to result in a greater than 99% reduction (within 24 h) in the number of viable gonococci recovered from ex vivo, human, primary cervical cell infections. These data provide strong support for the further development of Cz as a novel, host-targeted therapy to treat gonococcal cervicitis.
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Epilepsia , Gonorreia , Humanos , Feminino , Reposicionamento de Medicamentos , Gonorreia/tratamento farmacológico , Neisseria gonorrhoeae , Carbamazepina/uso terapêutico , Carbamazepina/farmacologiaRESUMO
Cutaneous melanoma is one of the most aggressive and deadly types of skin cancer and rates of disease are continuing to increase worldwide. Currently, no serum biomarkers exist for the early detection of cutaneous melanoma. Normal human cells cannot make the sialic acid sugar, Neu5Gc, yet human tumor cells express Neu5Gc and Neu5Gc-containing glycoconjugates have been proposed as tumor biomarkers. We engineered a Neu5Gc-specific lectin based on the pentameric B-subunit of the Shiga toxigenic Escherichia coli subtilase cytotoxin, termed SubB2M. We have detected elevated Neu5Gc-containing biomarkers in the sera of ovarian and breast cancer patients in a highly sensitive surface plasmon resonance (SPR)-based assay using our SubB2M lectin. Here, we used the SubB2M-SPR assay to investigate Neu5Gc-containing glycoconjugates in the serum of cutaneous melanoma patients. We found elevated total serum Neu5Gc levels in primary (n = 24) and metastatic (n = 38) patients compared to cancer-free controls (n = 34). Serum Neu5Gc levels detected with SubB2M can distinguish cutaneous melanoma patients from cancer-free controls with high sensitivity and specificity as determined by ROC curve analysis. These data indicate that serum Neu5Gc-containing glycoconjugates are a novel class of biomarkers for cutaneous melanoma, particularly for primary melanoma, and have the potential to contribute to the early diagnosis of this disease.
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Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Ácidos Neuramínicos , Lectinas , Biomarcadores Tumorais , Glicoconjugados , Melanoma Maligno CutâneoRESUMO
BACKGROUND: Revisions of total knee arthroplasties (TKAs) may require revision of one or both tibial and femoral components. Our purpose was to examine the clinical and functional outcomes in 1- versus 2-component TKA revisions. METHODS: We identified 92 1-component (tibial or femoral) revisions at a single center. Our inclusion criteria were isolated revision of the tibial or femoral components with a minimum 2-year follow-up. The included cases were matched 1:2 with a control group of 2-component revisions (tibial and femoral) by age, body mass index, American Society of Anesthesiologists score, and indication for revision. We collected demographics, complications, operative times, any subsequent rerevisions, and functional outcome scores. RESULTS: The median follow-up time for the 1- and 2-component revision groups were 10 years (range, 3 to 17) and 8 years (range, 2 to 18), respectively. The most common complication after rerevision in both groups was stiffness at 9 of 92 (9.8%) and 9 of 170 (5.3%) in the 1- and 2-component groups, respectively (P = .20). The overall complication prevalence in the 1- and 2- component revision groups was similar 20 of 92 (22%) and 35 of 170 (21%), respectively (P = .87). Subsequent rerevisions for any indication were encountered in 12 of 92 (13.0%) of the 1-component and 18 of 170 (11%) in the 2-component groups (P = .69). There was no statistical difference in survivorship or functional outcomes scores between the groups. CONCLUSION: Our results showed that isolated revision of a single TKA component is an acceptable option, with comparable functional outcomes, complications, and survivorships when compared with both-component revision. As such, a 1-component revision should be considered where appropriate.
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Artroplastia do Joelho , Humanos , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Articulação do Joelho/cirurgia , Prótese do Joelho/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese , Falha de Prótese , Reoperação/efeitos adversos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The COVID-19 pandemic, the most significant public health crisis since the 1918-1919 influenza epidemic, is the first such event to occur since the development of modern transportation systems in the twentieth century. Many states across the U.S. imposed lockdowns in early spring 2020, which reduced demand for trips of various types and affected transportation systems. In urban areas, the shift resulted in a reduction in traffic volumes and an increase in bicycling and walking in certain land use contexts. This paper seeks to understand the changes occurring at signalized intersections as a result of the lockdown and the ongoing pandemic, as well as the actions taken in response to these impacts. The results of a survey of agency reactions to COVID-19 with respect to traffic signal operations and changes in pedestrian activity during the spring 2020 lockdown using two case study examples in Utah are presented. First, the effects of placing intersections on pedestrian recall (with signage) to stop pedestrians from pushing the pedestrian button are examined. Next, the changes in pedestrian activity at Utah signalized intersections between the first 6 months of both 2019 and 2020 are analyzed and the impact of land use characteristics is explored. Survey results reveal the importance of using technologies such as adaptive systems and automated traffic signal performance measures to drive decisions. While pedestrian pushbutton actuations decreased in response to the implementation of pedestrian recalls, many pedestrians continued to use the pushbutton. Pedestrian activity changes were also largely driven by surrounding land uses.
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BACKGROUND & AIMS: Obesity-associated inflammation is a key player in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). However, the role of macrophage scavenger receptor 1 (MSR1, CD204) remains incompletely understood. METHODS: A total of 170 NAFLD liver biopsies were processed for transcriptomic analysis and correlated with clinicopathological features. Msr1-/- and wild-type mice were subjected to a 16-week high-fat and high-cholesterol diet. Mice and ex vivo human liver slices were treated with a monoclonal antibody against MSR1. Genetic susceptibility was assessed using genome-wide association study data from 1,483 patients with NAFLD and 430,101 participants of the UK Biobank. RESULTS: MSR1 expression was associated with the occurrence of hepatic lipid-laden foamy macrophages and correlated with the degree of steatosis and steatohepatitis in patients with NAFLD. Mice lacking Msr1 were protected against diet-induced metabolic disorder, showing fewer hepatic foamy macrophages, less hepatic inflammation, improved dyslipidaemia and glucose tolerance, and altered hepatic lipid metabolism. Upon induction by saturated fatty acids, MSR1 induced a pro-inflammatory response via the JNK signalling pathway. In vitro blockade of the receptor prevented the accumulation of lipids in primary macrophages which inhibited the switch towards a pro-inflammatory phenotype and the release of cytokines such as TNF-É. Targeting MSR1 using monoclonal antibody therapy in an obesity-associated NAFLD mouse model and human liver slices resulted in the prevention of foamy macrophage formation and inflammation. Moreover, we identified that rs41505344, a polymorphism in the upstream transcriptional region of MSR1, was associated with altered serum triglycerides and aspartate aminotransferase levels in a cohort of over 400,000 patients. CONCLUSIONS: Taken together, our data suggest that MSR1 plays a critical role in lipid-induced inflammation and could thus be a potential therapeutic target for the treatment of NAFLD. LAY SUMMARY: Non-alcoholic fatty liver disease (NAFLD) is a chronic disease primarily caused by excessive consumption of fat and sugar combined with a lack of exercise or a sedentary lifestyle. Herein, we show that the macrophage scavenger receptor MSR1, an innate immune receptor, mediates lipid uptake and accumulation in Kupffer cells, resulting in liver inflammation and thereby promoting the progression of NAFLD in humans and mice.
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Hepatopatia Gordurosa não Alcoólica , Animais , Anticorpos Monoclonais , Dieta Hiperlipídica/efeitos adversos , Estudo de Associação Genômica Ampla , Humanos , Inflamação/metabolismo , Lipídeos , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismoRESUMO
BACKGROUND & AIMS: Only a minority of excess alcohol drinkers develop cirrhosis. We developed and evaluated risk stratification scores to identify those at highest risk. METHODS: Three cohorts (GenomALC-1: n = 1,690, GenomALC-2: n = 3,037, UK Biobank: relevant n = 6,898) with a history of heavy alcohol consumption (≥80 g/day (men), ≥50 g/day (women), for ≥10 years) were included. Cases were participants with alcohol-related cirrhosis. Controls had a history of similar alcohol consumption but no evidence of liver disease. Risk scores were computed from up to 8 genetic loci identified previously as associated with alcohol-related cirrhosis and 3 clinical risk factors. Score performance for the stratification of alcohol-related cirrhosis risk was assessed and compared across the alcohol-related liver disease spectrum, including hepatocellular carcinoma (HCC). RESULTS: A combination of 3 single nucleotide polymorphisms (SNPs) (PNPLA3:rs738409, SUGP1-TM6SF2:rs10401969, HSD17B13:rs6834314) and diabetes status best discriminated cirrhosis risk. The odds ratios (ORs) and (95% CIs) between the lowest (Q1) and highest (Q5) score quintiles of the 3-SNP score, based on independent allelic effect size estimates, were 5.99 (4.18-8.60) (GenomALC-1), 2.81 (2.03-3.89) (GenomALC-2), and 3.10 (2.32-4.14) (UK Biobank). Patients with diabetes and high risk scores had ORs of 14.7 (7.69-28.1) (GenomALC-1) and 17.1 (11.3-25.7) (UK Biobank) compared to those without diabetes and with low risk scores. Patients with cirrhosis and HCC had significantly higher mean risk scores than patients with cirrhosis alone (0.76 ± 0.06 vs. 0.61 ± 0.02, p = 0.007). Score performance was not significantly enhanced by information on additional genetic risk variants, body mass index or coffee consumption. CONCLUSIONS: A risk score based on 3 genetic risk variants and diabetes status enables the stratification of heavy drinkers based on their risk of cirrhosis, allowing for the provision of earlier preventative interventions. LAY SUMMARY: Excessive chronic drinking leads to cirrhosis in some people, but so far there is no way to identify those at high risk of developing this debilitating disease. We developed a genetic risk score that can identify patients at high risk. The risk of cirrhosis is increased >10-fold with just two risk factors - diabetes and a high genetic risk score. Risk assessment using this test could enable the early and personalised management of this disease in high-risk patients.
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Predisposição Genética para Doença/classificação , Cirrose Hepática Alcoólica/diagnóstico , Medição de Risco/métodos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Estudos de Casos e Controles , Estudos de Coortes , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/fisiopatologia , Feminino , Estudo de Associação Genômica Ampla/métodos , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Humanos , Cirrose Hepática Alcoólica/etiologia , Cirrose Hepática Alcoólica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Medição de Risco/estatística & dados numéricosRESUMO
N -glycolylneuraminic acid (Neu5Gc), and its precursor N-acetylneuraminic acid (Neu5Ac), commonly referred to as sialic acids, are two of the most common glycans found in mammals. Humans carry a mutation in the enzyme that converts Neu5Ac into Neu5Gc, and as such, expression of Neu5Ac can be thought of as a 'human specific' trait. Bacteria can utilize sialic acids as a carbon and energy source and have evolved multiple ways to take up sialic acids. In order to generate free sialic acid, many bacteria produce sialidases that cleave sialic acid residues from complex glycan structures. In addition, sialidases allow escape from innate immune mechanisms, and can synergize with other virulence factors such as toxins. Human-adapted pathogens have evolved a preference for Neu5Ac, with many bacterial adhesins, and major classes of toxin, specifically recognizing Neu5Ac containing glycans as receptors. The preference of human-adapted pathogens for Neu5Ac also occurs during biosynthesis of surface structures such as lipo-oligosaccharide (LOS), lipo-polysaccharide (LPS) and polysaccharide capsules, subverting the human host immune system by mimicking the host. This review aims to provide an update on the advances made in understanding the role of sialic acid in bacteria-host interactions made in the last 5-10 years, and put these findings into context by highlighting key historical discoveries. We provide a particular focus on 'molecular mimicry' and incorporation of sialic acid onto the bacterial outer-surface, and the role of sialic acid as a receptor for bacterial adhesins and toxins.
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Ácido N-Acetilneuramínico , Ácidos Siálicos , Animais , Bactérias/genética , Bactérias/metabolismo , Humanos , Mamíferos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase , Ácidos Siálicos/metabolismo , Fatores de VirulênciaRESUMO
BACKGROUND AND AIMS: Only a minority of heavy drinkers progress to alcohol-associated cirrhosis (ALC). The aim of this study was to identify common genetic variants that underlie risk for ALC. APPROACH AND RESULTS: We analyzed data from 1,128 subjects of European ancestry with ALC and 614 heavy-drinking subjects without known liver disease from Australia, the United States, the United Kingdom, and three countries in Europe. A genome-wide association study (GWAS) was performed, adjusting for principal components and clinical covariates (alcohol use, age, sex, body mass index, and diabetes). We validated our GWAS findings using UK Biobank. We then performed a meta-analysis combining data from our study, the UK Biobank, and a previously published GWAS. Our GWAS found genome-wide significant risk association of rs738409 in patatin-like phospholipase domain containing 3 (PNPLA3) (odds ratio [OR] = 2.19 [G allele], P = 4.93 × 10-17 ) and rs4607179 near HSD17B13 (OR = 0.57 [C allele], P = 1.09 × 10-10 ) with ALC. Conditional analysis accounting for the PNPLA3 and HSD17B13 loci identified a protective association at rs374702773 in Fas-associated factor family member 2 (FAF2) (OR = 0.61 [del(T) allele], P = 2.56 × 10-8 ) for ALC. This association was replicated in the UK Biobank using conditional analysis (OR = 0.79, P = 0.001). Meta-analysis (without conditioning) confirmed genome-wide significance for the identified FAF2 locus as well as PNPLA3 and HSD17B13. Two other previously known loci (SERPINA1 and SUGP1/TM6SF2) were also genome-wide significant in the meta-analysis. GeneOntology pathway analysis identified lipid droplets as the target for several identified genes. In conclusion, our GWAS identified a locus at FAF2 associated with reduced risk of ALC among heavy drinkers. Like the PNPLA3 and HSD17B13 gene products, the FAF2 product has been localized to fat droplets in hepatocytes. CONCLUSIONS: Our genetic findings implicate lipid droplets in the biological pathway(s) underlying ALC.
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Predisposição Genética para Doença/genética , Cirrose Hepática Alcoólica/genética , Bases de Dados Genéticas , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
BACKGROUND: Normal human tissues do not express glycans terminating with the sialic acid N-glycolylneuraminic acid (Neu5Gc), yet Neu5Gc-containing glycans have been consistently found in human tumor tissues, cells and secretions and have been proposed as a cancer biomarker. We engineered a Neu5Gc-specific lectin called SubB2M, and previously reported elevated Neu5Gc biomarkers in serum from ovarian cancer patients using a Surface Plasmon Resonance (SPR)-based assay. Here we report an optimized SubB2M SPR-based assay and use this new assay to analyse sera from breast cancer patients for Neu5Gc levels. METHODS: To enhance specificity of our SPR-based assay, we included a non-sialic acid binding version of SubB, SubBA12, to control for any non-specific binding to SubB2M, which improved discrimination of cancer-free controls from early-stage ovarian cancer. We analysed 96 serum samples from breast cancer patients at all stages of disease compared to 22 cancer-free controls using our optimized SubB2M-A12-SPR assay. We also analysed a collection of serum samples collected at 6 monthly intervals from breast cancer patients at high risk for disease recurrence or spread. RESULTS: Analysis of sera from breast cancer cases revealed significantly elevated levels of Neu5Gc biomarkers at all stages of breast cancer. We show that Neu5Gc serum biomarker levels can discriminate breast cancer patients from cancer-free individuals with 98.96% sensitivity and 100% specificity. Analysis of serum collected prospectively, post-diagnosis, from breast cancer patients at high risk for disease recurrence showed a trend for a decrease in Neu5Gc levels immediately following treatment for those in remission. CONCLUSIONS: Neu5Gc serum biomarkers are a promising new tool for early detection and disease monitoring for breast cancer that may complement current imaging- and biopsy-based approaches.
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Neoplasias da Mama , Biomarcadores Tumorais , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Recidiva Local de Neoplasia , Ácidos Neuramínicos/metabolismoRESUMO
The extent to which climate change causes significant societal disruption remains controversial. An important example is the decline of the Akkadian Empire in northern Mesopotamia â¼4.2 ka, for which the existence of a coincident climate event is still uncertain. Here we present an Iranian stalagmite record spanning 5.2 ka to 3.7 ka, dated with 25 U/Th ages that provide an average age uncertainty of 31 y (1σ). We find two periods of increased Mg/Ca, beginning abruptly at 4.51 and 4.26 ka, and lasting 110 and 290 y, respectively. Each of these periods coincides with slower vertical stalagmite growth and a gradual increase in stable oxygen isotope ratios. The periods of high Mg/Ca are explained by periods of increased dust flux sourced from the Mesopotamia region, and the abrupt onset of this dustiness indicates threshold behavior in response to aridity. This interpretation is consistent with existing marine and terrestrial records from the broad region, which also suggest that the later, longer event beginning at 4.26 ka is of greater regional extent and/or amplitude. The chronological precision and high resolution of our record indicates that there is no significant difference, at decadal level, between the start date of the second, larger dust event and the timing of North Mesopotamia settlement abandonment, and furthermore reveals striking similarity between the total duration of the second dust event and settlement abandonment. The Iranian record demonstrates this region's threshold behavior in dust production, and its ability to maintain this climate state for multiple centuries naturally.
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Mudança Climática/história , Mudança Social/história , Cálcio/análise , Poeira/análise , História Antiga , Humanos , Magnésio/análise , Meteorologia/métodos , Oriente Médio , Isótopos de Oxigênio/análiseRESUMO
Leukocidin ED (LukED) is a pore-forming toxin produced by Staphylococcus aureus, which lyses host cells and promotes virulence of the bacteria. LukED enables S. aureus to acquire iron by lysing erythrocytes, which depends on targeting the host receptor Duffy antigen receptor for chemokines (DARC). The toxin also targets DARC on the endothelium, contributing to the lethality observed during bloodstream infection in mice. LukED is comprised of two monomers: LukE and LukD. LukE binds to DARC and facilitates hemolysis, but the closely related Panton-Valentine leukocidin S (LukS-PV) does not bind to DARC and is not hemolytic. The interaction of LukE with DARC and the role this plays in hemolysis are incompletely characterized. To determine the domain(s) of LukE that are critical for DARC binding, we studied the hemolytic function of LukE-LukS-PV chimeras, in which areas of sequence divergence (divergence regions, or DRs) were swapped between the toxins. We found that two regions of LukE's rim domain contribute to hemolysis, namely residues 57-75 (DR1) and residues 182-196 (DR4). Interestingly, LukE DR1 is sufficient to render LukS-PV capable of DARC binding and hemolysis. Further, LukE, by binding DARC through DR1, promotes the recruitment of LukD to erythrocytes, likely by facilitating LukED oligomer formation. Finally, we show that LukE targets murine Darc through DR1 in vivo to cause host lethality. These findings expand our biochemical understanding of the LukE-DARC interaction and the role that this toxin-receptor pair plays in S. aureus pathophysiology.
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Proteínas de Bactérias , Sistema do Grupo Sanguíneo Duffy , Eritrócitos , Exotoxinas , Proteínas Hemolisinas , Receptores de Superfície Celular , Staphylococcus aureus , Animais , Humanos , Camundongos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sistema do Grupo Sanguíneo Duffy/química , Sistema do Grupo Sanguíneo Duffy/genética , Sistema do Grupo Sanguíneo Duffy/metabolismo , Eritrócitos/química , Eritrócitos/metabolismo , Exotoxinas/química , Exotoxinas/genética , Exotoxinas/metabolismo , Domínios Proteicos , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Staphylococcus aureus/química , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismoRESUMO
BACKGROUND & AIMS: The protease plasmin is an important wound healing factor, but it is not clear how it affects gastrointestinal infection-mediated damage, such as that resulting from Clostridioides difficile. We investigated the role of plasmin in C difficile-associated disease. This bacterium produces a spore form that is required for infection, so we also investigated the effects of plasmin on spores. METHODS: C57BL/6J mice expressing the precursor to plasmin, the zymogen human plasminogen (hPLG), or infused with hPLG were infected with C difficile, and disease progression was monitored. Gut tissues were collected, and cytokine production and tissue damage were analyzed by using proteomic and cytokine arrays. Antibodies that inhibit either hPLG activation or plasmin activity were developed and structurally characterized, and their effects were tested in mice. Spores were isolated from infected patients or mice and visualized using super-resolution microscopy; the functional consequences of hPLG binding to spores were determined. RESULTS: hPLG localized to the toxin-damaged gut, resulting in immune dysregulation with an increased abundance of cytokines (such as interleukin [IL] 1A, IL1B, IL3, IL10, IL12B, MCP1, MP1A, MP1B, GCSF, GMCSF, KC, TIMP-1), tissue degradation, and reduced survival. Administration of antibodies that inhibit plasminogen activation reduced disease severity in mice. C difficile spores bound specifically to hPLG and active plasmin degraded their surface, facilitating rapid germination. CONCLUSIONS: We found that hPLG is recruited to the damaged gut, exacerbating C difficile disease in mice. hPLG binds to C difficile spores, and, upon activation to plasmin, remodels the spore surface, facilitating rapid spore germination. Inhibitors of plasminogen activation might be developed for treatment of C difficile or other infection-mediated gastrointestinal diseases.
Assuntos
Clostridioides difficile/efeitos dos fármacos , Enterocolite Pseudomembranosa/etiologia , Enterocolite Pseudomembranosa/patologia , Plasminogênio/farmacologia , Esporos Bacterianos/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Humanos , Intestino Delgado , Camundongos , Camundongos Endogâmicos C57BLRESUMO
INTRODUCTION: Sustained high alcohol intake is necessary but not sufficient to produce alcohol-related cirrhosis. Identification of risk factors, apart from lifetime alcohol exposure, would assist in discovery of mechanisms and prediction of risk. METHODS: We conducted a multicenter case-control study (GenomALC) comparing 1,293 cases (with alcohol-related cirrhosis, 75.6% male) and 754 controls (with equivalent alcohol exposure but no evidence of liver disease, 73.6% male). Information confirming or excluding cirrhosis, and on alcohol intake and other potential risk factors, was obtained from clinical records and by interview. Case-control differences in risk factors discovered in the GenomALC participants were validated using similar data from 407 cases and 6,573 controls from UK Biobank. RESULTS: The GenomALC case and control groups reported similar lifetime alcohol intake (1,374 vs 1,412 kg). Cases had a higher prevalence of diabetes (20.5% (262/1,288) vs 6.5% (48/734), P = 2.27 × 10-18) and higher premorbid body mass index (26.37 ± 0.16 kg/m2) than controls (24.44 ± 0.18 kg/m2, P = 5.77 × 10-15). Controls were significantly more likely to have been wine drinkers, coffee drinkers, smokers, and cannabis users than cases. Cases reported a higher proportion of parents who died of liver disease than controls (odds ratio 2.25 95% confidence interval 1.55-3.26). Data from UK Biobank confirmed these findings for diabetes, body mass index, proportion of alcohol as wine, and coffee consumption. DISCUSSION: If these relationships are causal, measures such as weight loss, intensive treatment of diabetes or prediabetic states, and coffee consumption should reduce the risk of alcohol-related cirrhosis.
Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Café , Diabetes Mellitus/epidemiologia , Cirrose Hepática Alcoólica/epidemiologia , Uso da Maconha/epidemiologia , Obesidade/epidemiologia , Fumar/epidemiologia , Chá , Bebidas Alcoólicas , Austrália/epidemiologia , Estudos de Casos e Controles , Feminino , França/epidemiologia , Alemanha/epidemiologia , Humanos , Modelos Logísticos , Masculino , Anamnese , Pessoa de Meia-Idade , Fatores de Risco , Suíça , Reino Unido/epidemiologia , Estados Unidos/epidemiologia , VinhoRESUMO
Inhibition of the NLRP3 inflammasome is a promising strategy for the development of new treatments for inflammatory diseases. MCC950 is a potent and specific small-molecule inhibitor of the NLRP3 pathway, but its molecular target is not defined. Here, we show that MCC950 directly interacts with the Walker B motif within the NLRP3 NACHT domain, thereby blocking ATP hydrolysis and inhibiting NLRP3 activation and inflammasome formation.