Amyloid pathology fingerprint differentiates post-traumatic stress disorder and traumatic brain injury

INTRODUCTION: Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are risk factors for early onset of Alzheimer's disease (AD) and may accelerate the progression rate of AD pathology. As amyloid-beta (Aβ) plaques are a hallmark of AD pathology, we hypothesized that TBI and PTSD might increase Aβ accumulation in the brain. METHODS: We examined PET and neuropsychological data from Vietnam War veterans compiled by the US Department of Defense Alzheimer's Disease Neuroimaging Initiative, to examine the spatial distribution of Aβ in male veterans' who had experienced a TBI and/or developed PTSD. Subjects were classified into controls, TBI only, PTSD only, and TBI with PTSD (TBI_PTSD) groups and data were analyzed using both voxel-based and ROI-based approaches. RESULTS: Compared to controls, all three clinical groups showed a pattern of mainly increased referenced standard uptake values (SUVR) for the amyloid tracer [18F]-AV45 PET, with rank order PTSD > TBI_PTSD > TBI > Control, and same rank order was seen in the deficits of cognitive functions. SUVR increase was observed in widespread cortical regions of the PTSD group; in white matter of the TBI_PTSD group; and cerebellum and precuneus area of the TBI group, in contrast with controls. The [18F]-AV45 SUVR correlated negatively with cerebrospinal fluid (CSF) amyloid levels and positively with the CSF tau concentrations. CONCLUSION: These results suggest that both TBI and PTSD are substantial risk factors for cognition decline and increased Aβ deposition resembling that in AD. In addition, both PTSD and TBI_PTSD have a different pathways of Aβ accumulation

GUIDELINES FOR GENETIC COUNSELLING AND TESTING FOR HEREDITARY BREAST AND OVARIAN CANCER

Tijekom posljednjih desetljeća svjedoci smo velikog napretka u izvedivosti i kliničkoj iskoristivosti genetičkog testiranja kod nasljednih karcinoma. Nasljedni karcinomi dojke i jajnika najčešće su posljedica mutacija u genima BRCA1 i BRCA2. Ovim smjernicama obuhvatili smo kriterije za upućivanje pacijenata na genetičko savjetovanje i testiranje; kriterije za upućivanje zdravih pojedinaca na prediktivno testiranje ako nije moguće testiranje oboljelog člana obitelji; postupak genetičkog savjetovanja prije i nakon testiranja; nalaz testiranja, kategorije nalaza i razine rizika; preporuke za daljnje praćenje osoba s povišenim rizikom; kemoprevenciju i profilaktičku kirurgiju kod nositelja/-ica patogenih mutacija gena BRCA 1 i BRCA 2; očuvanje reproduktivne funkcije u žena oboljelih od raka dojke i nositeljica mutacija BRCA i pristanak informiranog bolesnika na genetičko testiranje. Smjernice su namijenjene svim specijalistima koji su na bilo koji način uključeni u zbrinjavanje oboljelih od nasljednih karcinoma dojke i jajnika, a sastavila ih je radna skupina prema podacima iz relevantne medicinske literature te kliničkim iskustvima članova radne skupine.The last few decades have witnessed a great progress in feasibility and clinical utilization of genetic testing for hereditary cancers. Hereditary breast and ovarian cancers are most often the result of BRCA1 and BRCA2 gene mutations. In these guidelines we have covered: the criteria for referral of patients to genetic counselling and testing; the criteria for referral of healthy family members to predictive testing in the event when there is no possibility of testing the patient; the process of genetic counselling before and after testing; test results, their categories and risk levels; recommendations for monitoring of individuals with an increased risk; chemoprevention and prophylactic surgery for carriers of BRCA1 and BRCA2 gene mutations; preservation of reproductive function in women with breast cancer and in carriers of BRCA mutations; and informed consent for genetic testing. The guidelines are intended for all specialists who are in any way involved in the care of patients with hereditary breast and ovarian cancer, and are compiled by the working group according to the data from the relevant medical literature and from clinical experience of the members of the working group

Smjernice za genetičko savjetovanje i testiranje na nasljedni rak dojke i jajnika [Guidelines for genetic counselling and testing for hereditary breast and ovarian cancer]

The last few decades have witnessed a great progress in feasibility and clinical utilization of genetic testing for hereditary cancers. Hereditary breast and ovarian cancers are most often the result of BRCA1 and BRCA2 gene mutations. In these guidelines we have covered: the criteria for referral of patients to genetic counselling and testing; the criteria for referral of healthy family members to predictive testing in the event when there is no possibility of testing the patient; the process of genetic counselling before and after testing; test results, their categories and risk levels; recommendations for monitoring of individuals with an increased risk; chemoprevention and prophylactic surgery for carriers of BRCA1 and BRCA2 gene mutations; preservation of reproductive function in women with breast cancer and in carriers of BRCA mutations; and informed consent for genetic testing. The guidelines are intended for all specialists who are in any way involved in the care of patients with hereditary breast and ovarian cancer, and are compiled by the working group according to the data from the relevant medical literature and from clinical experience of the members of the working group

Homeostatic regulation of the endoneurial microenvironment during development, aging and in response to trauma, disease and toxic insult

The endoneurial microenvironment, delimited by the endothelium of endoneurial vessels and a multi-layered ensheathing perineurium, is a specialized milieu intérieur within which axons, associated Schwann cells and other resident cells of peripheral nerves function. The endothelium and perineurium restricts as well as regulates exchange of material between the endoneurial microenvironment and the surrounding extracellular space and thus is more appropriately described as a blood–nerve interface (BNI) rather than a blood–nerve barrier (BNB). Input to and output from the endoneurial microenvironment occurs via blood–nerve exchange and convective endoneurial fluid flow driven by a proximo-distal hydrostatic pressure gradient. The independent regulation of the endothelial and perineurial components of the BNI during development, aging and in response to trauma is consistent with homeostatic regulation of the endoneurial microenvironment. Pathophysiological alterations of the endoneurium in experimental allergic neuritis (EAN), and diabetic and lead neuropathy are considered to be perturbations of endoneurial homeostasis. The interactions of Schwann cells, axons, macrophages, and mast cells via cell–cell and cell–matrix signaling regulate the permeability of this interface. A greater knowledge of the dynamic nature of tight junctions and the factors that induce and/or modulate these key elements of the BNI will increase our understanding of peripheral nerve disorders as well as stimulate the development of therapeutic strategies to treat these disorders

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

Tobacco and alcohol use are leading causes of mortality that influence risk for many complex diseases and disorders 1 . They are heritable 2,3 and etiologically related 4,5 behaviors that have been resistant to gene discovery efforts 6–11 . 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

Target genes, variants, tissues and transcriptional pathways influencing human serum urate levels.

Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.The Genotype-Tissue Expression (GTEx) Project was supported by the Common Fund of the Office of the Director of the National Institutes of Health, and by NCI, NHGRI, NHLBI, NIDA, NIMH, and NINDS. Variant annotation was supported by software resources provided via the Caché Campus program of the InterSystems GmbH to Alexander Teumer

Genetic diversity fuels gene discovery for tobacco and alcohol use

Tobacco and alcohol use are heritable behaviours associated with 15% and 5.3% of worldwide deaths, respectively, due largely to broad increased risk for disease and injury(1-4). These substances are used across the globe, yet genome-wide association studies have focused largely on individuals of European ancestries(5). Here we leveraged global genetic diversity across 3.4 million individuals from four major clines of global ancestry (approximately 21% non-European) to power the discovery and fine-mapping of genomic loci associated with tobacco and alcohol use, to inform function of these loci via ancestry-aware transcriptome-wide association studies, and to evaluate the genetic architecture and predictive power of polygenic risk within and across populations. We found that increases in sample size and genetic diversity improved locus identification and fine-mapping resolution, and that a large majority of the 3,823 associated variants (from 2,143 loci) showed consistent effect sizes across ancestry dimensions. However, polygenic risk scores developed in one ancestry performed poorly in others, highlighting the continued need to increase sample sizes of diverse ancestries to realize any potential benefit of polygenic prediction.Peer reviewe

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms