Rare DNA variants in the brain-derived neurotrophic factor gene increase risk for attention-deficit hyperactivity disorder: a next-generation sequencing study

Attention-deficit hyperactivity disorder (ADHD) is a prevalent and highly heritable disorder of childhood with negative lifetime outcomes. Although candidate gene and genome-wide association studies have identified promising common variant signals, these explain only a fraction of the heritability of ADHD. The observation that rare structural variants confer substantial risk to psychiatric disorders suggests that rare variants might explain a portion of the missing heritability for ADHD. Here we believe we performed the first large-scale next-generation targeted sequencing study of ADHD in 152 child and adolescent cases and 188 controls across an a priori set of 117 genes. A multi-marker gene-level analysis of rare (<1% frequency) single-nucleotide variants (SNVs) revealed that the gene encoding brain-derived neurotrophic factor (BDNF) was associated with ADHD at Bonferroni corrected levels. Sanger sequencing confirmed the existence of all novel rare BDNF variants. Our results implicate BDNF as a genetic risk factor for ADHD, potentially by virtue of its critical role in neurodevelopment and synaptic plasticity.

GWAS meta-analysis reveals novel loci and genetic correlates for general cognitive function: a report from the COGENT consortium

The complex nature of human cognition has resulted in cognitive genomics lagging behind many other fields in terms of gene discovery using genome-wide association study (GWAS) methods. In an attempt to overcome these barriers, the current study utilized GWAS meta-analysis to examine the association of common genetic variation (~8M single-nucleotide polymorphisms (SNP) with minor allele frequency ⩾1%) to general cognitive function in a sample of 35 298 healthy individuals of European ancestry across 24 cohorts in the Cognitive Genomics Consortium (COGENT). In addition, we utilized individual SNP lookups and polygenic score analyses to identify genetic overlap with other relevant neurobehavioral phenotypes. Our primary GWAS meta-analysis identified two novel SNP loci (top SNPs: rs76114856 in the CENPO gene on chromosome 2 and rs6669072 near LOC105378853 on chromosome 1) associated with cognitive performance at the genome-wide significance level (P<5 × 10^-8). Gene-based analysis identified an additional three Bonferroni-corrected significant loci at chromosomes 17q21.31, 17p13.1 and 1p13.3. Altogether, common variation across the genome resulted in a conservatively estimated SNP heritability of 21.5% (s.e.=0.01%) for general cognitive function. Integration with prior GWAS of cognitive performance and educational attainment yielded several additional significant loci. Finally, we found robust polygenic correlations between cognitive performance and educational attainment, several psychiatric disorders, birth length/weight and smoking behavior, as well as a novel genetic association to the personality trait of openness. These data provide new insight into the genetics of neurocognitive function with relevance to understanding the pathophysiology of neuropsychiatric illness.

Silver nanoparticles in the environment: Sources, detection and ecotoxicology

The environmental impact of silver nanoparticles (AgNP) has become a topic of interest recently, this is due to the fact that AgNPs have been included in numerous consumer products including textiles, medical products, domestic appliances, food containers, cosmetics, paints and nano-functionalised plastics. The production, use and disposal of these AgNP containing products are potential routes for environmental exposure. These concerns have led to a number of studies investigating the release of particles from nano-functionalised products, the detection of the particles in the aquatic environment and the potential environmental toxicology of these AgNPs to aquatic organisms. The overall aim of this review is to examine methods for the capture and detection of AgNPs, potential toxicity and transmission routes in the aquatic environment.

A comprehensive treatment for peritoneal metastases from gastric cancer with curative intent

Recently, Peritoneal Surface Oncology Group International (PSOGI) developed a novel comprehensive treatment consisting of cytoreductive surgery (CRS) and perioperative chemotherapy (POC) for the treatment of peritoneal metastases (PM) from gastric cancer with curative intent. This article reviews the results of this treatment and verifies its indication. In this strategy, peritoneal cancer index (PCI) is determined by laparoscopy, and a peritoneal port is placed. Neoadjuvant bidirectional intraperitoneal/systemic chemotherapy (NIPS) is performed for 3 cycles, and then laparotomy is performed. Cytoreductive surgery with peritonectomy procedures and hyperthermic intraperitoneal chemoperfusion (HIPEC) are performed. Multivariate analyses showed that completeness of cytoreduction, pathologic response to NIPS and PCI level and cytologic status after NIPS, as independent prognostic factors. PCI less than cut-off level after NIPS, negative cytology after NIPS, and positive response to NIPS were identified as the indications for comprehensive treatment. Patients who hold these criteria should be considered as the candidates for CRS and HIPEC.

Reversal of Pathological Features of Graves' Orbitopathy by Activation of Forkhead Transcription Factors, FOXOs

CONTEXT

Graves' orbitopathy (GO) is a disfiguring/distressing, inflammatory autoimmune condition. This intractable problem is caused by expansion of the orbital contents around the eye by excessive fat generation (adipogenesis) and overproduction of extracellular matrix components, especially hyaluronan (HA) from preadipocytes/fibroblasts (PFs). Current immunosuppressive/antiinflammatory treatments are largely ineffective and have unpleasant side effects, and a better therapeutic strategy through understanding GO-associated pathological features is needed.

OBJECTIVE

Previously we identified depot-specific HA synthase 2 regulation (HAS2; major source of HA), which facilitates orbit-specific HA accumulation during adipogenesis, and targeting phosphatidylinositol-3-kinase/mechanistic target of rapamycin-complex-1 pathways blocked both pathological features. The current study revealed low expression levels of Forkhead box O (FOXOs; critical downstream effectors of phosphatidylinositol-3-kinase) in orbital PFs through adipogenesis compared with sc levels. We aimed to dissect the role of FOXOs in GO pathogenesis to identify nonimmunosuppressive targets for GO treatment.

DESIGN/SETTING/PARTICIPANTS

Human orbital and sc primary PFs were treated with small interfering RNA/chemical inhibitor (AS1842856) of FOXOs or FOXO enhancer trifluoperazine hydrochloride (TFP; Food and Drug Administration approved drug), in serum-free medium for 24 hours, or TFP treatment in adipogenic medium for 15 days.

MAIN OUTCOME MEASURES

Quantitative PCR was used to measure HAS2 transcripts and the terminal adipogenesis differentiation marker lipoprotein lipase. HA accumulation in the medium was measured by an ELISA.

RESULTS

Substantially increased or decreased HAS2/HA production was observed by inhibiting (small interfering RNA or chemical inhibitor) or enhancing (TFP) FOXO expression, respectively. TFP treatment is also sufficient to counteract thyrotropin receptor-activated HAS2/HA production and block adipogenesis in orbital PFs.

CONCLUSIONS

FOXOs play a crucial repressor role in the regulation of HAS2/HA production and adipogenesis in orbital PFs. Our data reveal for the first time that resetting GO-associated pathological features through drug-targeted activation of FOXOs could provide a feasible nonimmunosuppressive therapeutic strategy for GO.

Fertility and genomics: comparison of gene expression in contrasting reproductive tissues of female cattle

To compare gene expression among bovine tissues, large bovine RNA-seq datasets were used, comprising 280 samples from 10 different bovine tissues (uterine endometrium, granulosa cells, theca cells, cervix, embryos, leucocytes, liver, hypothalamus, pituitary, muscle) and generating 260 Gbases of data. Twin approaches were used: an information–theoretic analysis of the existing annotated transcriptome to identify the most tissue-specific genes and a de-novo transcriptome annotation to evaluate general features of the transcription landscape. Expression was detected for 97% of the Ensembl transcriptome with at least one read in one sample and between 28% and 66% at a level of 10 tags per million (TPM) or greater in individual tissues. Over 95% of genes exhibited some level of tissue-specific gene expression. This was mostly due to different levels of expression in different tissues rather than exclusive expression in a single tissue. Less than 1% of annotated genes exhibited a highly restricted tissue-specific expression profile and approximately 2% exhibited classic housekeeping profiles. In conclusion, it is the combined effects of the variable expression of large numbers of genes (73%–93% of the genome) and the specific expression of a small number of genes (<1% of the transcriptome) that contribute to determining the outcome of the function of individual tissues.

A combined segmenting and non-segmenting approach to signal quality estimation for ambulatory photoplethysmography

Continuous cardiac monitoring of healthy and unhealthy patients can help us understand the progression of heart disease and enable early treatment. Optical pulse sensing is an excellent candidate for continuous mobile monitoring of cardiovascular health indicators, but optical pulse signals are susceptible to corruption from a number of noise sources, including motion artifact. Therefore, before higher-level health indicators can be reliably computed, corrupted data must be separated from valid data. This is an especially difficult task in the presence of artifact caused by ambulation (e.g. walking or jogging), which shares significant spectral energy with the true pulsatile signal. In this manuscript, we present a machine-learning-based system for automated estimation of signal quality of optical pulse signals that performs well in the presence of periodic artifact. We hypothesized that signal processing methods that identified individual heart beats (segmenting approaches) would be more error-prone than methods that did not (non-segmenting approaches) when applied to data contaminated by periodic artifact. We further hypothesized that a fusion of segmenting and non-segmenting approaches would outperform either approach alone. Therefore, we developed a novel non-segmenting approach to signal quality estimation that we then utilized in combination with a traditional segmenting approach. Using this system we were able to robustly detect differences in signal quality as labeled by expert human raters (Pearson's r = 0.9263). We then validated our original hypotheses by demonstrating that our non-segmenting approach outperformed the segmenting approach in the presence of contaminated signal, and that the combined system outperformed either individually. Lastly, as an example, we demonstrated the utility of our signal quality estimation system in evaluating the trustworthiness of heart rate measurements derived from optical pulse signals.

The one and the many: effects of the cell adhesion molecule pathway on neuropsychological function in psychosis

BACKGROUND

Genetic studies of single gene variants have been criticized as providing a simplistic characterization of the genetic basis of illness risk that ignores the effects of other variants within the same biological pathways. Of candidate biological pathways for schizophrenia (SZ), the cell adhesion molecule (CAM) pathway has repeatedly been linked to both psychosis and neurocognitive dysfunction. Here we tested, using risk allele scores derived from the Schizophrenia Psychiatric Genome-Wide Association Study Consortium (PGC-SCZ), whether alleles within the CAM pathway were correlated with poorer neuropsychological function in patients.

METHOD

In total, 424 patients with psychosis were assessed in areas of cognitive ability typically found to be impaired in SZ: intelligence quotient, memory, working memory and attentional control. CAM pathway genes were identified using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Alleles within these genes identified as significantly associated with SZ risk in the PGC-SCZ were then used to calculate a CAM pathway-based polygenic risk allele score for each patient and these scores were tested for association with cognitive ability.

RESULTS

Increased CAM pathway polygenic risk scores were significantly associated with poorer performance on measures of memory and attention, explaining 1-3% of variation on these measures. Notably, the most strongly associated single nucleotide polymorphism (SNP) in the CAM pathway (rs9272105 within HLA-DQA1) explained a similar amount of variance in attentional control, but not memory, as the polygenic risk analysis.

CONCLUSIONS

These data support a role for the CAM pathway in cognitive function, both at the level of individual SNPs and the wider pathway. In so doing these data highlight the value of pathway-based polygenic risk score studies as well as single gene studies for understanding SZ-associated deficits in cognition.

Possible targets for nonimmunosuppressive therapy of Graves' orbitopathy

CONTEXT

Graves' orbitopathy (GO) is caused by expansion of the orbital contents by excess adipogenesis and overproduction of hyaluronan (HA). Immunosuppressive and antiinflammatory treatments of GO are not always effective and can have side effects, whereas targeting GO-associated tissue remodeling might be a more logical therapeutic strategy. Previously we reported that signaling cascades through IGF1 receptor and thyrotropin receptor within orbital preadipocytes/fibroblasts drove adipogenesis and HA production. Our current study combined the stimulation of IGF1 receptor and thyrotropin receptor increase of HA accumulation, which we hypothesize is by activation of phosphatidylinositol 3-kinase (PI3K)-1A/PI3K1B, respectively. The central aim of this study was to investigate whether PI3K/mammalian target of rapamycin complex 1 (mTORC1) inhibitors affected adipogenesis and/or HA production within orbital preadipocyte/fibroblasts.

METHODS

Human orbital preadipocytes were treated with/without inhibitors, LY294002 (PI3K1A/mTORC1), AS-605240 (PI3K1B), or PI103 (PI3K1A/mTORC1) in serum-free medium for 24 hours or cultured in adipogenic medium for 15 days. Quantitative PCR was used to measure hyaluronan synthases (HAS2) transcripts and the terminal adipogenesis differentiation marker lipoprotein lipase. HA accumulation in the medium was measured by an ELISA.

RESULTS

Unlike AS-605240, both LY294002 (10 μM) and PI-103 (5 μM) significantly decreased HAS2 transcripts/HA accumulation and adipogenesis. Because PI-103 and LY294002 are dual PI3K/mTOR inhibitors, we investigated the inhibition of mTORC1 (rapamycin 100 nM), which significantly decreased adipogenesis but had no effect on HAS2 transcripts/HA, implicating PI3K-1A in the latter.

CONCLUSIONS

The combined inhibition of PI3K1A and mTORC1 signaling in vitro decreased both HA accumulation and adipogenesis. Because PI3K and mTOR inhibitors are clinically used to treat other conditions, they have the potential to be repositioned to be used as an alternative nonimmunosuppressive therapy of GO.

'There's no place like home': perceptions of home-based HIV testing in Lesotho

HIV testing has the potential to reduce HIV transmission by identifying and counseling individuals with HIV, reducing risk behaviors, linking persons with HIV to care and earlier treatment, and reducing perinatal transmission. In Lesotho, a high HIV prevalence country in which a large proportion of the population has never tested for HIV, home-based testing (HBT) may be an important strategy to increase HIV testing. We identified factors influencing acceptability of HIV prevention strategies among a convenience sample of 200 pregnant or post-partum Basotho women and 30 Basotho men. We first conducted cross-sectional surveys, followed by key informant interviews with all 30 men and focus group discussions with a sub-set of 62 women. In total, 82% of women reported positive perceptions of HBT; women and men viewed HBT as a potential way to increase testing among men and saw the home as a comfortable, supportive environment for testing and counseling couples and families together. Potential barriers to HBT uptake included concerns about confidentiality, privacy, coercion to test, conflict within the family and fear of HIV/AIDS-associated stigma. Participants emphasized community mobilization and education as important elements of HBT.

Montreal prognostic score: estimating survival of patients with non-small cell lung cancer using clinical biomarkers

Background:

For evidence-based medical practice, well-defined risk scoring systems are essential to identify patients with a poor prognosis. The objective of this study was to develop a prognostic score, the Montreal prognostic score (MPS), to improve prognostication of patients with incurable non-small cell lung cancer (NSCLC) in everyday practice.

Methods:

A training cohort (TC) and a confirmatory cohort (CC) of newly diagnosed patients with NSCLC planning to receive chemotherapy were used to develop the MPS. Stage and clinically available biomarkers were entered into a Cox model and risk weights were estimated. C-statistics were used to test the accuracy.

Results:

The TC consisted of 258 patients and the CC consisted of 433 patients. Montreal prognostic score classified patients into three distinct groups with median survivals of 2.5 months (95% confidence interval (CI): 1.8, 4.2), 8.2 months (95% CI: 7.0, 9.4) and 18.2 months (95% CI: 14.0, 27.5), respectively (log-rank, P<0.001). Overall, the C-statistics were 0.691 (95% CI: 0.685, 0.697) for the TC and 0.665 (95% CI: 0.661, 0.670) for the CC.

Conclusion:

The MPS, by classifying patients into three well-defined prognostic groups, provides valuable information, which physicians could use to better inform their patients about treatment options, especially the best timing to involve palliative care teams.