DOM Recent Discoveries

Recent Discoveries


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Development and Validation of a Mucosal Impedance Contour Analysis System to Distinguish Esophageal Disorders.

Development and Validation of a Mucosal Impedance Contour Analysis System to Distinguish Esophageal Disorders.

Gastroenterology. 2019 Jan 31;:

Authors: Patel DA, Higginbotham T, Slaughter JC, Aslam M, Yuksel E, Katzka D, Gyawali CP, Mashi M, Pandolfino J, Vaezi MF

Abstract
BACKGROUND: Diagnostic testing for chronic esophageal disorders rely on histopathology analysis of biopsies or uncomfortable transnasal catheters or wireless pH monitoring, which capture abnormal intraluminal refluxate. We therefore developed a balloon mucosal impedance (MI) catheter system that instantly detects changes in esophageal mucosal integrity during endoscopy over a long segment of the esophagus. We performed a prospective study to evaluate the ability of a balloon-incorporated MI catheter to detect and evaluate esophageal disorders, including gastroesophageal reflux disease (GERD) and eosinophilic esophagitis (EoE).
METHODS: We performed a prospective study of 69 patients undergoing esophagogastroduodenoscopy with or without wireless pH monitoring. Patients were classified as having GERD (erosive esophagitis or abnormal pH; n = 24), EoE (confirmed with pathology analysis of tissues from both distal and proximal esophagus; n = 21), or non-GERD (normal results from esophagogastroduodenoscopy and pH tests; n = 24). Receiver operating characteristic curves (ROC) and area under the ROC curve (AUC) were used to compare the accuracy of balloon MI in diagnosis. Probabilities of assignment to each group (GERD, non-GERD, or EoE) were estimated using multinomial logistic regression. Association between MI patterns and diagnoses were validated using data from patients seen at 3 separate institutions.
RESULTS: MI pattern along the esophageal axis differed significantly (p <0.01) among patients with GERD, EoE and non-GERD. Patients with non-GERD had higher MI values along all measured segments. The MI pattern for GERD was easily distinguished from that of EoE: in patients with GERD, MI values were low in the distal esophagus and normalized along the proximal esophagus, whereas in patients with EoE, measurements were low in all segments of the esophagus. Intercept and rate of rise of MI value (slope) as distance increased from the squamo-columnar junction identified patients with GERD with an AUC = 0.67, patients with EoE with an AUC of 0.84, and patients with non-GERD with an AUC = 0.83 in the development cohort. One patient had an adverse event (reported mild chest pain after the procedure) and was discharged from the hospital without further events.
CONCLUSIONS: We developed a balloon MI catheter system that instantly detects changes in esophageal mucosal integrity during endoscopy and found it to be safe and able to identify patients with GERD, EoE, or non-GERD. We validated our findings in a separate cohort for patients.

PMID: 30711626 [PubMed - as supplied by publisher]

Endosomolytic polymersomes increase the activity of cyclic dinucleotide STING agonists to enhance cancer immunotherapy.

Endosomolytic polymersomes increase the activity of cyclic dinucleotide STING agonists to enhance cancer immunotherapy.

Nat Nanotechnol. 2019 Jan 21;:

Authors: Shae D, Becker KW, Christov P, Yun DS, Lytton-Jean AKR, Sevimli S, Ascano M, Kelley M, Johnson DB, Balko JM, Wilson JT

Abstract
Cyclic dinucleotide (CDN) agonists of stimulator of interferon genes (STING) are a promising class of immunotherapeutics that activate innate immunity to increase tumour immunogenicity. However, the efficacy of CDNs is limited by drug delivery barriers, including poor cellular targeting, rapid clearance and inefficient transport to the cytosol where STING is localized. Here, we describe STING-activating nanoparticles (STING-NPs)-rationally designed polymersomes for enhanced cytosolic delivery of the endogenous CDN ligand for STING, 2'3' cyclic guanosine monophosphate-adenosine monophosphate (cGAMP). STING-NPs increase the biological potency of cGAMP, enhance STING signalling in the tumour microenvironment and sentinel lymph node, and convert immunosuppressive tumours to immunogenic, tumoricidal microenvironments. This leads to enhanced therapeutic efficacy of cGAMP, inhibition of tumour growth, increased rates of long-term survival, improved response to immune checkpoint blockade and induction of immunological memory that protects against tumour rechallenge. We validate STING-NPs in freshly isolated human melanoma tissue, highlighting their potential to improve clinical outcomes of immunotherapy.

PMID: 30664751 [PubMed - as supplied by publisher]

Author Correction: Assembly of a pan-genome from deep sequencing of 910 humans of African descent.

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Author Correction: Assembly of a pan-genome from deep sequencing of 910 humans of African descent.

Nat Genet. 2019 Jan 15;:

Authors: Sherman RM, Forman J, Antonescu V, Puiu D, Daya M, Rafaels N, Boorgula MP, Chavan S, Vergara C, Ortega VE, Levin AM, Eng C, Yazdanbakhsh M, Wilson JG, Marrugo J, Lange LA, Williams LK, Watson H, Ware LB, Olopade CO, Olopade O, Oliveira RR, Ober C, Nicolae DL, Meyers DA, Mayorga A, Knight-Madden J, Hartert T, Hansel NN, Foreman MG, Ford JG, Faruque MU, Dunston GM, Caraballo L, Burchard EG, Bleecker ER, Araujo MI, Herrera-Paz EF, Campbell M, Foster C, Taub MA, Beaty TH, Ruczinski I, Mathias RA, Barnes KC, Salzberg SL

Abstract
In the version of this article initially published, the statement "there are no pan-genomes for any other animal or plant species" was incorrect. The statement has been corrected to "there are no reported pan-genomes for any other animal species, to our knowledge." We thank David Edwards for bringing this error to our attention. The error has been corrected in the HTML and PDF versions of the article.

PMID: 30647471 [PubMed - as supplied by publisher]

Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use.

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Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use.

Nat Genet. 2019 Jan 14;:

Authors: Liu M, Jiang Y, Wedow R, Li Y, Brazel DM, Chen F, Datta G, Davila-Velderrain J, McGuire D, Tian C, Zhan X, 23andMe Research Team, HUNT All-In Psychiatry, Choquet H, Docherty AR, Faul JD, Foerster JR, Fritsche LG, Gabrielsen ME, Gordon SD, Haessler J, Hottenga JJ, Huang H, Jang SK, Jansen PR, Ling Y, Mägi R, Matoba N, McMahon G, Mulas A, Orrù V, Palviainen T, Pandit A, Reginsson GW, Skogholt AH, Smith JA, Taylor AE, Turman C, Willemsen G, Young H, Young KA, Zajac GJM, Zhao W, Zhou W, Bjornsdottir G, Boardman JD, Boehnke M, Boomsma DI, Chen C, Cucca F, Davies GE, Eaton CB, Ehringer MA, Esko T, Fiorillo E, Gillespie NA, Gudbjartsson DF, Haller T, Harris KM, Heath AC, Hewitt JK, Hickie IB, Hokanson JE, Hopfer CJ, Hunter DJ, Iacono WG, Johnson EO, Kamatani Y, Kardia SLR, Keller MC, Kellis M, Kooperberg C, Kraft P, Krauter KS, Laakso M, Lind PA, Loukola A, Lutz SM, Madden PAF, Martin NG, McGue M, McQueen MB, Medland SE, Metspalu A, Mohlke KL, Nielsen JB, Okada Y, Peters U, Polderman TJC, Posthuma D, Reiner AP, Rice JP, Rimm E, Rose RJ, Runarsdottir V, Stallings MC, Stančáková A, Stefansson H, Thai KK, Tindle HA, Tyrfingsson T, Wall TL, Weir DR, Weisner C, Whitfield JB, Winsvold BS, Yin J, Zuccolo L, Bierut LJ, Hveem K, Lee JJ, Munafò MR, Saccone NL, Willer CJ, Cornelis MC, David SP, Hinds DA, Jorgenson E, Kaprio J, Stitzel JA, Stefansson K, Thorgeirsson TE, Abecasis G, Liu DJ, Vrieze S

Abstract
Tobacco and alcohol use are leading causes of mortality that influence risk for many complex diseases and disorders1. They are heritable2,3 and etiologically related4,5 behaviors that have been resistant to gene discovery efforts6-11. In sample sizes up to 1.2 million individuals, we discovered 566 genetic variants in 406 loci associated with multiple stages of tobacco use (initiation, cessation, and heaviness) as well as alcohol use, with 150 loci evidencing pleiotropic association. Smoking phenotypes were positively genetically correlated with many health conditions, whereas alcohol use was negatively correlated with these conditions, such that increased genetic risk for alcohol use is associated with lower disease risk. We report evidence for the involvement of many systems in tobacco and alcohol use, including genes involved in nicotinic, dopaminergic, and glutamatergic neurotransmission. The results provide a solid starting point to evaluate the effects of these loci in model organisms and more precise substance use measures.

PMID: 30643251 [PubMed - as supplied by publisher]

Genome-wide meta-analysis identifies new loci and functional pathways influencing Alzheimer's disease risk.

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Genome-wide meta-analysis identifies new loci and functional pathways influencing Alzheimer's disease risk.

Nat Genet. 2019 Jan 07;:

Authors: Jansen IE, Savage JE, Watanabe K, Bryois J, Williams DM, Steinberg S, Sealock J, Karlsson IK, Hägg S, Athanasiu L, Voyle N, Proitsi P, Witoelar A, Stringer S, Aarsland D, Almdahl IS, Andersen F, Bergh S, Bettella F, Bjornsson S, Brækhus A, Bråthen G, de Leeuw C, Desikan RS, Djurovic S, Dumitrescu L, Fladby T, Hohman TJ, Jonsson PV, Kiddle SJ, Rongve A, Saltvedt I, Sando SB, Selbæk G, Shoai M, Skene NG, Snaedal J, Stordal E, Ulstein ID, Wang Y, White LR, Hardy J, Hjerling-Leffler J, Sullivan PF, van der Flier WM, Dobson R, Davis LK, Stefansson H, Stefansson K, Pedersen NL, Ripke S, Andreassen OA, Posthuma D

Abstract
Alzheimer's disease (AD) is highly heritable and recent studies have identified over 20 disease-associated genomic loci. Yet these only explain a small proportion of the genetic variance, indicating that undiscovered loci remain. Here, we performed a large genome-wide association study of clinically diagnosed AD and AD-by-proxy (71,880 cases, 383,378 controls). AD-by-proxy, based on parental diagnoses, showed strong genetic correlation with AD (rg = 0.81). Meta-analysis identified 29 risk loci, implicating 215 potential causative genes. Associated genes are strongly expressed in immune-related tissues and cell types (spleen, liver, and microglia). Gene-set analyses indicate biological mechanisms involved in lipid-related processes and degradation of amyloid precursor proteins. We show strong genetic correlations with multiple health-related outcomes, and Mendelian randomization results suggest a protective effect of cognitive ability on AD risk. These results are a step forward in identifying the genetic factors that contribute to AD risk and add novel insights into the neurobiology of AD.

PMID: 30617256 [PubMed - as supplied by publisher]

Myeloid-Specific Deletion of Epsins 1 and 2 Reduces Atherosclerosis by Preventing LRP-1 Downregulation.

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Myeloid-Specific Deletion of Epsins 1 and 2 Reduces Atherosclerosis by Preventing LRP-1 Downregulation.

Circ Res. 2018 Dec 31;:

Authors: Brophy ML, Dong Y, Tao H, Yancey PG, Song K, Zhang K, Wen A, Wu H, Lee Y, Malovichko MV, Sithu SD, Wong S, Yu L, Kocher O, Bischoff J, Srivastava S, Linton MF, Ley K, Chen H

Abstract
RATIONALE: Atherosclerosis is in part caused by immune and inflammatory cell infiltration into the vascular wall, leading to enhanced inflammation and lipid accumulation in the aortic endothelium. Understanding the molecular mechanisms underlying this disease is critical for the development of new therapies. Our recent studies demonstrate that epsins, a family of ubiquitin-binding endocytic adaptors, are critical regulators of atherogenicity. Given the fundamental contribution lesion macrophages make to fuel atherosclerosis, whether and how myeloid specific epsins promote atherogenesis is an open and significant question.
OBJECTIVE: We will determine the role of myeloid specific epsins in regulating lesion macrophage function during atherosclerosis.
METHODS AND RESULTS: We engineered myeloid cell-specific epsins double knockout mice (LysM-DKO) on an ApoE-/- background. On Western diet, these mice exhibited marked decrease in atherosclerotic lesion formation, diminished immune and inflammatory cell content in aortas, and reduced necrotic core content but increased smooth muscle cell content in aortic root sections. Epsins deficiency hindered foam cell formation and suppressed pro-inflammatory macrophage phenotype but increased efferocytosis and anti-inflammatory macrophage phenotype in primary macrophages. Mechanistically, we show that epsins loss specifically increased total and surface levels of LRP-1, an efferocytosis receptor with anti-atherosclerotic properties. We further show that epsin and LRP-1 interact via epsin's Ubiquitin Interacting Motif (UIM) domain. Oxidized LDL treatment increased LRP-1 ubiquitination, subsequent binding to epsin, and its internalization from the cell surface, suggesting that epsins promote the ubiquitin-dependent internalization and downregulation of LRP-1. Crossing ApoE-/-/LysM-DKO mice onto an LRP-1 heterozygous background restored, in part, atherosclerosis, suggesting that epsin-mediated LRP-1 downregulation in macrophages plays a pivotal role in propelling atherogenesis.
CONCLUSIONS: Myeloid epsins promote atherogenesis by facilitating pro-inflammatory macrophage recruitment and inhibiting efferocytosis in part by downregulating LRP-1, implicating that targeting epsins in macrophages may serve as a novel therapeutic strategy to treat atherosclerosis.

PMID: 30595089 [PubMed - as supplied by publisher]

Varicose Veins Reach New Heights.

Varicose Veins Reach New Heights.

Circulation. 2018 Dec 18;138(25):2881-2883

Authors: Wells QS

PMID: 30566011 [PubMed - in process]

Antibiotic allergy.

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Antibiotic allergy.

Lancet. 2018 Dec 14;:

Authors: Blumenthal KG, Peter JG, Trubiano JA, Phillips EJ

Abstract
Antibiotics are the commonest cause of life-threatening immune-mediated drug reactions that are considered off-target, including anaphylaxis, and organ-specific and severe cutaneous adverse reactions. However, many antibiotic reactions documented as allergies were unknown or not remembered by the patient, cutaneous reactions unrelated to drug hypersensitivity, drug-infection interactions, or drug intolerances. Although such reactions pose negligible risk to patients, they currently represent a global threat to public health. Antibiotic allergy labels result in displacement of first-line therapies for antibiotic prophylaxis and treatment. A penicillin allergy label, in particular, is associated with increased use of broad-spectrum and non-β-lactam antibiotics, which results in increased adverse events and antibiotic resistance. Most patients labelled as allergic to penicillins are not allergic when appropriately stratified for risk, tested, and re-challenged. Given the public health importance of penicillin allergy, this Review provides a global update on antibiotic allergy epidemiology, classification, mechanisms, and management.

PMID: 30558872 [PubMed - as supplied by publisher]

Transmission of drug-resistant tuberculosis in HIV-endemic settings.

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Transmission of drug-resistant tuberculosis in HIV-endemic settings.

Lancet Infect Dis. 2018 Dec 13;:

Authors: Khan PY, Yates TA, Osman M, Warren RM, van der Heijden Y, Padayatchi N, Nardell EA, Moore D, Mathema B, Gandhi N, Eldholm V, Dheda K, Hesseling AC, Mizrahi V, Rustomjee R, Pym A

Abstract
The emergence and expansion of the multidrug-resistant tuberculosis epidemic is a threat to the global control of tuberculosis. Multidrug-resistant tuberculosis is the result of the selection of resistance-conferring mutations during inadequate antituberculosis treatment. However, HIV has a profound effect on the natural history of tuberculosis, manifesting in an increased rate of disease progression, leading to increased transmission and amplification of multidrug-resistant tuberculosis. Interventions specific to HIV-endemic areas are urgently needed to block tuberculosis transmission. These interventions should include a combination of rapid molecular diagnostics and improved chemotherapy to shorten the duration of infectiousness, implementation of infection control measures, and active screening of multidrug-resistant tuberculosis contacts, with prophylactic regimens for individuals without evidence of disease. Development and improvement of the efficacy of interventions will require a greater understanding of the factors affecting the transmission of multidrug-resistant tuberculosis in HIV-endemic settings, including population-based molecular epidemiology studies. In this Series article, we review what we know about the transmission of multidrug-resistant tuberculosis in settings with high burdens of HIV and define the research priorities required to develop more effective interventions, to diminish ongoing transmission and the amplification of drug resistance.

PMID: 30554996 [PubMed - as supplied by publisher]

Advances in the understanding of Mycobacterium tuberculosis transmission in HIV-endemic settings.

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Advances in the understanding of Mycobacterium tuberculosis transmission in HIV-endemic settings.

Lancet Infect Dis. 2018 Dec 13;:

Authors: Peters JS, Andrews JR, Hatherill M, Hermans S, Martinez L, Schurr E, van der Heijden Y, Wood R, Rustomjee R, Kana BD

Abstract
Tuberculosis claims more human lives than any other infectious disease. This alarming epidemic has fuelled the development of novel antimicrobials and diagnostics. However, public health interventions that interrupt transmission have been slow to emerge, particularly in HIV-endemic settings. Transmission of tuberculosis is complex, involving various environmental, bacteriological, and host factors, among which concomitant HIV infection is important. Preventing person-to-person spread is central to halting the epidemic and, consequently, tuberculosis transmission is now being studied with renewed interest. In this Series paper, we review recent advances in the understanding of tuberculosis transmission, from the view of source-case infectiousness, inherent susceptibility of exposed individuals, appending tools for predicting risk of disease progression, the biophysical nature of the contagion, and the environments in which transmission occurs and is sustained in populations. We focus specifically on how HIV infection affects these features with a view to describing novel transmission blocking strategies in HIV-endemic settings.

PMID: 30554995 [PubMed - as supplied by publisher]

Association Between Titin Loss-of-Function Variants and Early-Onset Atrial Fibrillation.

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Association Between Titin Loss-of-Function Variants and Early-Onset Atrial Fibrillation.

JAMA. 2018 Dec 11;320(22):2354-2364

Authors: Choi SH, Weng LC, Roselli C, Lin H, Haggerty CM, Shoemaker MB, Barnard J, Arking DE, Chasman DI, Albert CM, Chaffin M, Tucker NR, Smith JD, Gupta N, Gabriel S, Margolin L, Shea MA, Shaffer CM, Yoneda ZT, Boerwinkle E, Smith NL, Silverman EK, Redline S, Vasan RS, Burchard EG, Gogarten SM, Laurie C, Blackwell TW, Abecasis G, Carey DJ, Fornwalt BK, Smelser DT, Baras A, Dewey FE, Jaquish CE, Papanicolaou GJ, Sotoodehnia N, Van Wagoner DR, Psaty BM, Kathiresan S, Darbar D, Alonso A, Heckbert SR, Chung MK, Roden DM, Benjamin EJ, Murray MF, Lunetta KL, Lubitz SA, Ellinor PT, DiscovEHR study and the NHLBI Trans-Omics for Precision Medicine (TOPMed) Consortium

Abstract
Importance: Atrial fibrillation (AF) is the most common arrhythmia affecting 1% of the population. Young individuals with AF have a strong genetic association with the disease, but the mechanisms remain incompletely understood.
Objective: To perform large-scale whole-genome sequencing to identify genetic variants related to AF.
Design, Setting, and Participants: The National Heart, Lung, and Blood Institute's Trans-Omics for Precision Medicine Program includes longitudinal and cohort studies that underwent high-depth whole-genome sequencing between 2014 and 2017 in 18 526 individuals from the United States, Mexico, Puerto Rico, Costa Rica, Barbados, and Samoa. This case-control study included 2781 patients with early-onset AF from 9 studies and identified 4959 controls of European ancestry from the remaining participants. Results were replicated in the UK Biobank (346 546 participants) and the MyCode Study (42 782 participants).
Exposures: Loss-of-function (LOF) variants in genes at AF loci and common genetic variation across the whole genome.
Main Outcomes and Measures: Early-onset AF (defined as AF onset in persons <66 years of age). Due to multiple testing, the significance threshold for the rare variant analysis was P = 4.55 × 10-3.
Results: Among 2781 participants with early-onset AF (the case group), 72.1% were men, and the mean (SD) age of AF onset was 48.7 (10.2) years. Participants underwent whole-genome sequencing at a mean depth of 37.8 fold and mean genome coverage of 99.1%. At least 1 LOF variant in TTN, the gene encoding the sarcomeric protein titin, was present in 2.1% of case participants compared with 1.1% in control participants (odds ratio [OR], 1.76 [95% CI, 1.04-2.97]). The proportion of individuals with early-onset AF who carried a LOF variant in TTN increased with an earlier age of AF onset (P value for trend, 4.92 × 10-4), and 6.5% of individuals with AF onset prior to age 30 carried a TTN LOF variant (OR, 5.94 [95% CI, 2.64-13.35]; P = 1.65 × 10-5). The association between TTN LOF variants and AF was replicated in an independent study of 1582 patients with early-onset AF (cases) and 41 200 control participants (OR, 2.16 [95% CI, 1.19-3.92]; P = .01).
Conclusions and Relevance: In a case-control study, there was a statistically significant association between an LOF variant in the TTN gene and early-onset AF, with the variant present in a small percentage of participants with early-onset AF (the case group). Further research is necessary to understand whether this is a causal relationship.

PMID: 30535219 [PubMed - in process]

Breast Cancer Risk After Recent Childbirth: A Pooled Analysis of 15 Prospective Studies.

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Breast Cancer Risk After Recent Childbirth: A Pooled Analysis of 15 Prospective Studies.

Ann Intern Med. 2018 Dec 11;:

Authors: Nichols HB, Schoemaker MJ, Cai J, Xu J, Wright LB, Brook MN, Jones ME, Adami HO, Baglietto L, Bertrand KA, Blot WJ, Boutron-Ruault MC, Dorronsoro M, Dossus L, Eliassen AH, Giles GG, Gram IT, Hankinson SE, Hoffman-Bolton J, Kaaks R, Key TJ, Kitahara CM, Larsson SC, Linet M, Merritt MA, Milne RL, Pala V, Palmer JR, Peeters PH, Riboli E, Sund M, Tamimi RM, Tjønneland A, Trichopoulou A, Ursin G, Vatten L, Visvanathan K, Weiderpass E, Wolk A, Zheng W, Weinberg CR, Swerdlow AJ, Sandler DP

Abstract
Background: Parity is widely recognized as protective for breast cancer, but breast cancer risk may be increased shortly after childbirth. Whether this risk varies with breastfeeding, family history of breast cancer, or specific tumor subtype has rarely been evaluated.
Objective: To characterize breast cancer risk in relation to recent childbirth.
Design: Pooled analysis of individual-level data from 15 prospective cohort studies.
Setting: The international Premenopausal Breast Cancer Collaborative Group.
Participants: Women younger than 55 years.
Measurements: During 9.6 million person-years of follow-up, 18 826 incident cases of breast cancer were diagnosed. Hazard ratios (HRs) and 95% CIs for breast cancer were calculated using Cox proportional hazards regression.
Results: Compared with nulliparous women, parous women had an HR for breast cancer that peaked about 5 years after birth (HR, 1.80 [95% CI, 1.63 to 1.99]) before decreasing to 0.77 (CI, 0.67 to 0.88) after 34 years. The association crossed over from positive to negative about 24 years after birth. The overall pattern was driven by estrogen receptor (ER)-positive breast cancer; no crossover was seen for ER-negative cancer. Increases in breast cancer risk after childbirth were pronounced when combined with a family history of breast cancer and were greater for women who were older at first birth or who had more births. Breastfeeding did not modify overall risk patterns.
Limitations: Breast cancer diagnoses during pregnancy were not uniformly distinguishable from early postpartum diagnoses. Data on human epidermal growth factor receptor 2 (HER2) oncogene overexpression were limited.
Conclusion: Compared with nulliparous women, parous women have an increased risk for breast cancer for more than 20 years after childbirth. Health care providers should consider recent childbirth a risk factor for breast cancer in young women.
Primary Funding Source: The Avon Foundation, the National Institute of Environmental Health Sciences, Breast Cancer Now and the UK National Health Service, and the Institute of Cancer Research.

PMID: 30534999 [PubMed - as supplied by publisher]

Bone Marrow-Derived Proangiogenic Cells Mediate Pulmonary Arteriole Stiffening via Serotonin 2B Receptor Dependent Mechanism.

Bone Marrow-Derived Proangiogenic Cells Mediate Pulmonary Arteriole Stiffening via Serotonin 2B Receptor Dependent Mechanism.

Circ Res. 2018 Dec 07;123(12):e51-e64

Authors: Bloodworth NC, Clark CR, West JD, Snider JC, Gaskill C, Shay S, Scott C, Bastarache J, Gladson S, Moore C, D'Amico R, Brittain EL, Tanjore H, Blackwell TS, Majka SM, Merryman WD

Abstract
RATIONALE: Pulmonary arterial hypertension is a deadly disease of the pulmonary vasculature for which no disease-modifying therapies exist. Small-vessel stiffening and remodeling are fundamental pathological features of pulmonary arterial hypertension that occur early and drive further endovascular cell dysfunction. Bone marrow (BM)-derived proangiogenic cells (PACs), a specialized heterogeneous subpopulation of myeloid lineage cells, are thought to play an important role in pathogenesis.
OBJECTIVE: To determine whether BM-derived PACs directly contributed to experimental pulmonary hypertension (PH) by promoting small-vessel stiffening through 5-HT2B (serotonin 2B receptor)-mediated signaling.
METHODS AND RESULTS: We performed BM transplants using transgenic donor animals expressing diphtheria toxin secondary to activation of an endothelial-specific tamoxifen-inducible Cre and induced experimental PH using hypoxia with SU5416 to enhance endovascular injury and ablated BM-derived PACs, after which we measured right ventricular systolic pressures in a closed-chest procedure. BM-derived PAC lineage tracing was accomplished by transplanting BM from transgenic donor animals with fluorescently labeled hematopoietic cells and treating mice with a 5-HT2B antagonist. BM-derived PAC ablation both prevented and reversed experimental PH with SU5416-enhanced endovascular injury, reducing the number of muscularized pulmonary arterioles and normalizing arteriole stiffness as measured by atomic force microscopy. Similarly, treatment with a pharmacological antagonist of 5-HT2B also prevented experimental PH, reducing the number and stiffness of muscularized pulmonary arterioles. PACs accelerated pulmonary microvascular endothelial cell injury response in vitro, and the presence of BM-derived PACs significantly correlated with stiffer pulmonary arterioles in pulmonary arterial hypertension patients and mice with experimental PH. RNA sequencing of BM-derived PACs showed that 5-HT2B antagonism significantly altered biologic pathways regulating cell proliferation, locomotion and migration, and cytokine production and response to cytokine stimulus.
CONCLUSIONS: Together, our findings illustrate that BM-derived PACs directly contribute to experimental PH with SU5416-enhanced endovascular injury by mediating small-vessel stiffening and remodeling in a 5-HT2B signaling-dependent manner.

PMID: 30566041 [PubMed - in process]

Large-scale Genome-wide Association Study of East Asians Identifies Loci Associated With Risk for Colorectal Cancer.

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Large-scale Genome-wide Association Study of East Asians Identifies Loci Associated With Risk for Colorectal Cancer.

Gastroenterology. 2018 Dec 06;:

Authors: Lu Y, Kweon SS, Tanikawa C, Jia WH, Xiang YB, Cai Q, Zeng C, Schmit SL, Shin A, Matsuo K, Jee SH, Kim DH, Kim J, Wen W, Shi J, Guo X, Li B, Wang N, Zhang B, Li X, Shin MH, Li HL, Ren Z, Oh JH, Oze I, Ahn YO, Jung KJ, Conti DV, Schumacher FR, Rennert G, Jenkins MA, Campbell PT, Hoffmeister M, Casey G, Gruber SB, Gao J, Gao YT, Pan ZZ, Kamatani Y, Zeng YX, Shu XO, Long J, Matsuda K, Zheng W

Abstract
BACKGROUND & AIMS: Genome-wide association studies (GWASs) have associated approximately 50 loci with risk of colorectal cancer (CRC)-nearly one-third of these loci were initially associated with CRC in studies conducted in East Asian populations. We conducted a GWAS of East Asians to identify CRC risk loci and evaluate the generalizability of findings from GWAS of European populations to Asian populations METHODS: We analyzed genetic data from 22,775 patients with CRC (cases) and 47,731 individuals without cancer (controls) from 14 studies in the Asia Colorectal Cancer Consortium. First, we performed a meta-analysis of 7 GWAS (10,625 cases and 34,595 controls) and identified 46,554 promising risk variants for replication by adding them to the Multi-Ethnic Global Array (MEGA) for genotype analysis in 6445 cases and 7175 controls. These data were analyzed, along with data from additional 5705 cases and 5961 controls genotyped using the ONCOARRAY: We also obtained data from 57,976 cases and 67,242 controls of European descent. Variants at identified risk loci were functionally annotated and evaluated in correlation with gene expression levels.
RESULTS: A meta-analyses of all samples from people of Asian descent identified 13 loci and 1 new variant at a known locus (10q24.2) associated with risk of CRC at the genome-wide significance level of P<5 x 10-8. We did not perform experiments to replicate these associations in additional individuals of Asian ancestry. However, the lead risk variant in 6 of these loci was also significantly associated with risk of CRC in European descendants. A strong association (44%-75% increase in risk per allele) was found for 2 low-frequency variants: rs201395236 at 1q44 (minor allele frequency, 1.34%) and rs77969132 at 12p11.21 (minor allele frequency, 1.53%). For 8 of the 13 associated loci, the variants with the highest levels of significant association were located inside or near the protein-coding genes L1TD1, EFCAB2, PPP1R21, SLCO2A1, HLA-G, NOTCH4, DENND5B, and GNAS. For other inter-genic loci, we provided evidence for the possible involvement of the genes ALDH7A1, PRICKLE1, KLF5, WWOX, and GLP2R. We replicated findings for 41 of 52 previously reported risk loci.
CONCLUSIONS: We showed that most of the risk loci previously associated with CRC risk in individuals of European descent were also associated with CRC risk in East Asians. Furthermore, we identified 13 loci significantly associated with risk for CRC in Asians. Many of these loci contained genes that regulate the immune response, Wnt signaling to beta-catenin, prostaglandin E2 catabolism, and cell pluripotency and proliferation. Further analyses of these genes and their variants is warranted-particularly for the 8 loci for which the lead CRC risk variants were not replicated in persons of European descent.

PMID: 30529582 [PubMed - as supplied by publisher]

Phase I/II Study of Stem-Cell Transplantation Using a Single Cord Blood Unit Expanded Ex Vivo With Nicotinamide.

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Phase I/II Study of Stem-Cell Transplantation Using a Single Cord Blood Unit Expanded Ex Vivo With Nicotinamide.

J Clin Oncol. 2018 Dec 04;:JCO1800053

Authors: Horwitz ME, Wease S, Blackwell B, Valcarcel D, Frassoni F, Boelens JJ, Nierkens S, Jagasia M, Wagner JE, Kuball J, Koh LP, Majhail NS, Stiff PJ, Hanna R, Hwang WYK, Kurtzberg J, Cilloni D, Freedman LS, Montesinos P, Sanz G

Abstract
PURPOSE: Increasing the number of hematopoietic stem and progenitor cells within an umbilical cord blood (UCB) graft shortens the time to hematopoietic recovery after UCB transplantation. In this study, we assessed the safety and efficacy of a UCB graft that was expanded ex vivo in the presence of nicotinamide and transplanted after myeloablative conditioning as a stand-alone hematopoietic stem-cell graft.
METHODS: Thirty-six patients with hematologic malignancies underwent transplantation at 11 sites.
RESULTS: The cumulative incidence of neutrophil engraftment at day 42 was 94%. Two patients experienced secondary graft failure attributable to viral infections. Hematopoietic recovery was compared with that observed in recipients of standard UCB transplantation as reported to the Center for International Blood and Marrow Transplant Research (n = 146). The median time to neutrophil recovery was 11.5 days (95% CI, 9 to 14 days) for recipients of nicotinamide-expanded UCB and 21 days (95% CI, 20 to 23 days) for the comparator ( P < .001). The median time to platelet recovery was 34 days (95% CI, 32 to 42 days) and 46 days (95% CI, 42 to 50 days) for the expanded and the comparator cohorts, respectively ( P < .001). The cumulative incidence of grade 2 to 4 acute graft-versus-host disease (GVHD) at day 100 was 44%, and grade 3 and 4 acute GVHD at day 100 was 11%. The cumulative incidence at 2 years of all chronic GVHD was 40%, and moderate/severe chronic GVHD was 10%. The 2-year cumulative incidences of nonrelapse mortality and relapse were 24% and 33%, respectively. The 2-year probabilities of overall and disease-free survival were 51% and 43%, respectively.
CONCLUSION: UCB expanded ex vivo with nicotinamide shortens median neutrophil recovery by 9.5 days (95% CI, 7 to 12 days) and median platelet recovery by 12 days (95% CI, 3 to 16.5 days). This trial establishes feasibility, safety, and efficacy of an ex vivo expanded UCB unit as a stand-alone graft.

PMID: 30523748 [PubMed - as supplied by publisher]

Association of Oral Anticoagulants and Proton Pump Inhibitor Cotherapy With Hospitalization for Upper Gastrointestinal Tract Bleeding.

Association of Oral Anticoagulants and Proton Pump Inhibitor Cotherapy With Hospitalization for Upper Gastrointestinal Tract Bleeding.

JAMA. 2018 Dec 04;320(21):2221-2230

Authors: Ray WA, Chung CP, Murray KT, Smalley WE, Daugherty JR, Dupont WD, Stein CM

Abstract
Importance: Anticoagulant choice and proton pump inhibitor (PPI) cotherapy could affect the risk of upper gastrointestinal tract bleeding, a frequent and potentially serious complication of oral anticoagulant treatment.
Objectives: To compare the incidence of hospitalization for upper gastrointestinal tract bleeding in patients using individual anticoagulants with and without PPI cotherapy, and to determine variation according to underlying gastrointestinal bleeding risk.
Design, Setting, and Participants: Retrospective cohort study in Medicare beneficiaries between January 1, 2011, and September 30, 2015.
Exposures: Apixaban, dabigatran, rivaroxaban, or warfarin with or without PPI cotherapy.
Main Outcomes and Measures: Hospitalizations for upper gastrointestinal tract bleeding: adjusted incidence and risk difference (RD) per 10 000 person-years of anticoagulant treatment, incidence rate ratios (IRRs).
Results: There were 1 643 123 patients with 1 713 183 new episodes of oral anticoagulant treatment included in the cohort (mean [SD] age, 76.4 [2.4] years, 651 427 person-years of follow-up [56.1%] were for women, and the indication was atrial fibrillation for 870 330 person-years [74.9%]). During 754 389 treatment person-years without PPI cotherapy, the adjusted incidence of hospitalization for upper gastrointestinal tract bleeding (n = 7119) was 115 per 10 000 person-years (95% CI, 112-118). The incidence for rivaroxaban (n = 1278) was 144 per 10 000 person-years (95% CI, 136-152), which was significantly greater than the incidence of hospitalizations for apixaban (n = 279; 73 per 10 000 person-years; IRR, 1.97 [95% CI, 1.73-2.25]; RD, 70.9 [95% CI, 59.1-82.7]), dabigatran (n = 629; 120 per 10 000 person-years; IRR, 1.19 [95% CI, 1.08-1.32]; RD, 23.4 [95% CI, 10.6-36.2]), and warfarin (n = 4933; 113 per 10 000 person-years; IRR, 1.27 [95% CI, 1.19-1.35]; RD, 30.4 [95% CI, 20.3-40.6]). The incidence for apixaban was significantly lower than that for dabigatran (IRR, 0.61 [95% CI, 0.52-0.70]; RD, -47.5 [95% CI,-60.6 to -34.3]) and warfarin (IRR, 0.64 [95% CI, 0.57-0.73]; RD, -40.5 [95% CI, -50.0 to -31.0]). When anticoagulant treatment with PPI cotherapy (264 447 person-years; 76 per 10 000 person-years) was compared with treatment without PPI cotherapy, risk of upper gastrointestinal tract bleeding hospitalizations (n = 2245) was lower overall (IRR, 0.66 [95% CI, 0.62-0.69]) and for apixaban (IRR, 0.66 [95% CI, 0.52-0.85]; RD, -24 [95% CI, -38 to -11]), dabigatran (IRR, 0.49 [95% CI, 0.41-0.59]; RD, -61.1 [95% CI, -74.8 to -47.4]), rivaroxaban (IRR, 0.75 [95% CI, 0.68-0.84]; RD, -35.5 [95% CI, -48.6 to -22.4]), and warfarin (IRR, 0.65 [95% CI, 0.62-0.69]; RD, -39.3 [95% CI, -44.5 to -34.2]).
Conclusions and Relevance: Among patients initiating oral anticoagulant treatment, incidence of hospitalization for upper gastrointestinal tract bleeding was the highest in patients prescribed rivaroxaban, and the lowest for patients prescribed apixaban. For each anticoagulant, the incidence of hospitalization for upper gastrointestinal tract bleeding was lower among patients who were receiving PPI cotherapy. These findings may inform assessment of risks and benefits when choosing anticoagulant agents.

PMID: 30512099 [PubMed - in process]

ACC/AHA Versus ESC Guidelines for Diagnosis and Management of Peripheral Artery Disease: JACC Guideline Comparison.

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ACC/AHA Versus ESC Guidelines for Diagnosis and Management of Peripheral Artery Disease: JACC Guideline Comparison.

J Am Coll Cardiol. 2018 Dec 04;72(22):2789-2801

Authors: Kithcart AP, Beckman JA

Abstract
Peripheral artery disease is a common yet underdiagnosed cause of morbidity worldwide. Significant recent advances in management have resulted in new guideline creation for the diagnosis and management of peripheral artery disease in the United States and Europe. Here, we analyze each set of guidelines with special attention to those areas where the 2 groups disagree. Both groups emphasize the importance of risk factor reduction, including smoking cessation, lipid lowering, blood pressure management, and glucose control. The U.S. guidelines place additional attention on lifestyle factors, including regular physical activity and supervised exercise. The European guidelines offer a number of recommendations for revascularization in patients with limb-threatening ischemia. Both agree that more evidence is needed to understand which patients are at highest risk for tissue loss. A consistent charge to each committee fostering a similar approach to available data and more randomized studies would align recommendations across both organizations.

PMID: 30497565 [PubMed - in process]

Human islets expressing HNF1A variant have defective β cell transcriptional regulatory networks.

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Human islets expressing HNF1A variant have defective β cell transcriptional regulatory networks.

J Clin Invest. 2018 Dec 03;:

Authors: Haliyur R, Tong X, Sanyoura M, Shrestha S, Lindner J, Saunders DC, Aramandla R, Poffenberger G, Redick SD, Bottino R, Prasad N, Levy SE, Blind RD, Harlan DM, Philipson LH, Stein RW, Brissova M, Powers AC

Abstract
Using an integrated approach to characterize the pancreatic tissue and isolated islets from a 33-year-old with 17 years of type 1 diabetes (T1D), we found that donor islets contained β cells without insulitis and lacked glucose-stimulated insulin secretion despite a normal insulin response to cAMP-evoked stimulation. With these unexpected findings for T1D, we sequenced the donor DNA and found a pathogenic heterozygous variant in the gene encoding hepatocyte nuclear factor-1α (HNF1A). In one of the first studies of human pancreatic islets with a disease-causing HNF1A variant associated with the most common form of monogenic diabetes, we found that HNF1A dysfunction leads to insulin-insufficient diabetes reminiscent of T1D by impacting the regulatory processes critical for glucose-stimulated insulin secretion and suggest a rationale for a therapeutic alternative to current treatment.

PMID: 30507613 [PubMed - as supplied by publisher]

Discovery of common and rare genetic risk variants for colorectal cancer.

Discovery of common and rare genetic risk variants for colorectal cancer.

Nat Genet. 2018 Dec 03;:

Authors: Huyghe JR, Bien SA, Harrison TA, Kang HM, Chen S, Schmit SL, Conti DV, Qu C, Jeon J, Edlund CK, Greenside P, Wainberg M, Schumacher FR, Smith JD, Levine DM, Nelson SC, Sinnott-Armstrong NA, Albanes D, Alonso MH, Anderson K, Arnau-Collell C, Arndt V, Bamia C, Banbury BL, Baron JA, Berndt SI, Bézieau S, Bishop DT, Boehm J, Boeing H, Brenner H, Brezina S, Buch S, Buchanan DD, Burnett-Hartman A, Butterbach K, Caan BJ, Campbell PT, Carlson CS, Castellví-Bel S, Chan AT, Chang-Claude J, Chanock SJ, Chirlaque MD, Cho SH, Connolly CM, Cross AJ, Cuk K, Curtis KR, de la Chapelle A, Doheny KF, Duggan D, Easton DF, Elias SG, Elliott F, English DR, Feskens EJM, Figueiredo JC, Fischer R, FitzGerald LM, Forman D, Gala M, Gallinger S, Gauderman WJ, Giles GG, Gillanders E, Gong J, Goodman PJ, Grady WM, Grove JS, Gsur A, Gunter MJ, Haile RW, Hampe J, Hampel H, Harlid S, Hayes RB, Hofer P, Hoffmeister M, Hopper JL, Hsu WL, Huang WY, Hudson TJ, Hunter DJ, Ibañez-Sanz G, Idos GE, Ingersoll R, Jackson RD, Jacobs EJ, Jenkins MA, Joshi AD, Joshu CE, Keku TO, Key TJ, Kim HR, Kobayashi E, Kolonel LN, Kooperberg C, Kühn T, Küry S, Kweon SS, Larsson SC, Laurie CA, Le Marchand L, Leal SM, Lee SC, Lejbkowicz F, Lemire M, Li CI, Li L, Lieb W, Lin Y, Lindblom A, Lindor NM, Ling H, Louie TL, Männistö S, Markowitz SD, Martín V, Masala G, McNeil CE, Melas M, Milne RL, Moreno L, Murphy N, Myte R, Naccarati A, Newcomb PA, Offit K, Ogino S, Onland-Moret NC, Pardini B, Parfrey PS, Pearlman R, Perduca V, Pharoah PDP, Pinchev M, Platz EA, Prentice RL, Pugh E, Raskin L, Rennert G, Rennert HS, Riboli E, Rodríguez-Barranco M, Romm J, Sakoda LC, Schafmayer C, Schoen RE, Seminara D, Shah M, Shelford T, Shin MH, Shulman K, Sieri S, Slattery ML, Southey MC, Stadler ZK, Stegmaier C, Su YR, Tangen CM, Thibodeau SN, Thomas DC, Thomas SS, Toland AE, Trichopoulou A, Ulrich CM, Van Den Berg DJ, van Duijnhoven FJB, Van Guelpen B, van Kranen H, Vijai J, Visvanathan K, Vodicka P, Vodickova L, Vymetalkova V, Weigl K, Weinstein SJ, White E, Win AK, Wolf CR, Wolk A, Woods MO, Wu AH, Zaidi SH, Zanke BW, Zhang Q, Zheng W, Scacheri PC, Potter JD, Bassik MC, Kundaje A, Casey G, Moreno V, Abecasis GR, Nickerson DA, Gruber SB, Hsu L, Peters U

Abstract
To further dissect the genetic architecture of colorectal cancer (CRC), we performed whole-genome sequencing of 1,439 cases and 720 controls, imputed discovered sequence variants and Haplotype Reference Consortium panel variants into genome-wide association study data, and tested for association in 34,869 cases and 29,051 controls. Findings were followed up in an additional 23,262 cases and 38,296 controls. We discovered a strongly protective 0.3% frequency variant signal at CHD1. In a combined meta-analysis of 125,478 individuals, we identified 40 new independent signals at P < 5 × 10-8, bringing the number of known independent signals for CRC to ~100. New signals implicate lower-frequency variants, Krüppel-like factors, Hedgehog signaling, Hippo-YAP signaling, long noncoding RNAs and somatic drivers, and support a role for immune function. Heritability analyses suggest that CRC risk is highly polygenic, and larger, more comprehensive studies enabling rare variant analysis will improve understanding of biology underlying this risk and influence personalized screening strategies and drug development.

PMID: 30510241 [PubMed - as supplied by publisher]