618 research outputs found
Genetic heterogeneity in infantile spasms
Infantile spasms (IS) is a developmental and epileptic encephalopathy with heterogeneous etiologies including many genetic causes. Genetic studies have identified pathogenic variants in over 30 genes as causes of IS. Many of these genetic causes are extremely rare, with only one reported incidence in an individual with IS. To better understand the genetic landscape of IS, we used targeted sequencing to screen 42 candidate IS genes and 53 established developmental and epileptic encephalopathy genes in 92 individual with IS. We identified a genetic diagnosis for 7.6% of our cohort, including pathogenic variants in KCNB1 (n = 2), GNA01 (n = 1), STXBP1 (n = 1), SLC35A2 (n = 1), TBLIXR1 (n = 1), and K1F1A (n = 1). Our data emphasize the genetic heterogeneity of IS and will inform the diagnosis and management of individuals with this devastating disorder.Peer reviewe
Validation of loci at 2q14.2 and 15q21.3 as risk factors for testicular cancer.
Testicular germ cell tumor (TGCT), the most common cancer in men aged 18 to 45 years, has a strong heritable basis. Genome-wide association studies (GWAS) have proposed single nucleotide polymorphisms (SNPs) at a number of loci influencing TGCT risk. To further evaluate the association of recently proposed risk SNPs with TGCT at 2q14.2, 3q26.2, 7q36.3, 10q26.13 and 15q21.3, we analyzed genotype data on 3,206 cases and 7,422 controls. Our analysis provides independent replication of the associations for risk SNPs at 2q14.2 (rs2713206 at P = 3.03 × 10-2; P-meta = 3.92 × 10-8; nearest gene, TFCP2L1) and rs12912292 at 15q21.3 (P = 7.96 × 10-11; P-meta = 1.55 × 10-19; nearest gene PRTG). Case-only analyses did not reveal specific associations with TGCT histology. TFCP2L1 joins the growing list of genes located within TGCT risk loci with biologically plausible roles in developmental transcriptional regulation, further highlighting the importance of this phenomenon in TGCT oncogenesis
Pulses of Class I PI3kinase activity identify the release and recapture of prey from neutrophil phagosomes
Class I PI3kinases coordinate the delivery of microbicidal effectors to the phagosome by forming the phosphoinositide lipid second messenger, phosphatidylinositol (3, 4, 5)-trisphosphate (PIP3). However, the dynamics of PIP3 in neutrophils during a bacterial infection are unknown. We have therefore developed an in vivo, live zebrafish infection model that enables visualisation of dynamic changes in Class 1 PI3kinases (PI3K) signalling on neutrophil phagosomes in real-time. We have identified that on approximately 12% of neutrophil phagosomes PHAkt-eGFP, a reporter for Class 1 PI3K signalling, re-recruits in pulsatile bursts. This phenomenon occurred on phagosomes containingstructurally and morphologically distinct prey, including Staphylococcus aureus and Mycobacterium abscessus, and was dependent on the activity of the Class 1 PI3K isoform, PI3kinase γ. Detailed imaging suggested that ‘pulsing phagosomes’ represent neutrophils transiently reopening and reclosing phagosomes. This finding challenges the concept that phagosomes remain closed after preyengulfment and we propose that neutrophils occasionally use this alternative pathway of phagosome maturation to release phagosome contents and/or to restart phagosome maturation if digestion has stalle
Toll-like receptor orchestrates a tumor suppressor response in non-small cell lung cancer
Targeting early-stage lung cancer is vital to improve survival. However, the mechanisms and components of the early tumor suppressor response in lung cancer are not well understood. In this report, we study the role of Toll-like receptor 2 (TLR2), a regulator of oncogene-induced senescence, which is a key tumor suppressor response in premalignancy. Using human lung cancer samples and genetically engineered mouse models, we show that TLR2 is active early in lung tumorigenesis, where it correlates with improved survival and clinical regression. Mechanistically, TLR2 impairs early lung cancer progression via activation of cell intrinsic cell cycle arrest pathways and the proinflammatory senescence-associated secretory phenotype (SASP). The SASP regulates non-cell autonomous anti-tumor responses, such as immune surveillance of premalignant cells, and we observe impaired myeloid cell recruitment to lung tumors after Tlr2 loss. Last, we show that administration of a TLR2 agonist reduces lung tumor growth, highlighting TLR2 as a possible therapeutic target.F.R.M. is funded by a Wellcome Trust clinical research fellowship through the Edinburgh Clinical Academic Track (ECAT) program (203913/Z/16/Z), a Wellcome Trust-ISSF3 award (IS3-R1.07 20/21), and a Wellcome Trust iTPA award (209710/Z/17/Z). J.C.A. core lab funding was received from Cancer Research UK (C47559/A16243, Training and Career Development Board – Career Development Fellowship), the University of Edinburgh (Chancellor’s Fellowship), and the Ministry of Science and Innovation of the Government of Spain (Proyecto PID2020-117860GB-100 financiado por MCIN/AEI/10.13039/501100011033). S.W. is supported by a Cancer Research UK senior fellowship (A29576). J.C. is supported by a Wellcome Trust clinical lectureship through the ECAT program (203913/Z/16/Z). M.M. is supported by a CRUK Edinburgh Centre Award (C157/A25140). S.V. and J.F.P. are funded by National Institute on Aging (NIA) grants (R01AG 68048-1 and UG3CA 268103-1)
Fine-mapping identifies multiple prostate cancer risk loci at 5p15, one of which associates with TERT expression
Associations between single nucleotide polymorphisms (SNPs) at 5p15 and multiple cancer types have been reported. We have previously shown evidence for a strong association between prostate cancer (PrCa) risk and rs2242652 at 5p15, intronic in the telomerase reverse transcriptase (TERT) gene that encodes TERT. To comprehensively evaluate the association between genetic variation across this region and PrCa, we performed a fine-mapping analysis by genotyping 134 SNPs using a custom Illumina iSelect array or Sequenom MassArray iPlex, followed by imputation of 1094 SNPs in 22 301 PrCa cases and 22 320 controls in The PRACTICAL consortium. Multiple stepwise logistic regression analysis identified four signals in the promoter or intronic regions of TERT that independently associated with PrCa risk. Gene expression analysis of normal prostate tissue showed evidence that SNPs within one of these regions also associated with TERT expression, providing a potential mechanism for predisposition to disease
Pathogenic MAST3 Variants in the STK Domain Are Associated with Epilepsy
Objective: The MAST family of microtubule-associated serine–threonine kinases (STKs) have distinct expression patterns in the developing and mature human and mouse brain. To date, only MAST1 has been conclusively associated with neurological disease, with de novo variants in individuals with a neurodevelopmental disorder, including a mega corpus callosum. Methods: Using exome sequencing, we identify MAST3 missense variants in individuals with epilepsy. We also assess the effect of these variants on the ability of MAST3 to phosphorylate the target gene product ARPP-16 in HEK293T cells. Results: We identify de novo missense variants in the STK domain in 11 individuals, including 2 recurrent variants p.G510S (n = 5) and p.G515S (n = 3). All 11 individuals had developmental and epileptic encephalopathy, with 8 having normal development prior to seizure onset at \u3c2 years of age. All patients developed multiple seizure types, 9 of 11 patients had seizures triggered by fever and 9 of 11 patients had drug-resistant seizures. In vitro analysis of HEK293T cells transfected with MAST3 cDNA carrying a subset of these patient-specific missense variants demonstrated variable but generally lower expression, with concomitant increased phosphorylation of the MAST3 target, ARPP-16, compared to wild-type. These findings suggest the patient-specific variants may confer MAST3 gain-of-function. Moreover, single-nuclei RNA sequencing and immunohistochemistry shows that MAST3 expression is restricted to excitatory neurons in the cortex late in prenatal development and postnatally. Interpretation: In summary, we describe MAST3 as a novel epilepsy-associated gene with a potential gain-of-function pathogenic mechanism that may be primarily restricted to excitatory neurons in the cortex. ANN NEUROL 2021;90:274–284
Management of cutaneous metastases using electrochemotherapy
Background. Cutaneous metastases may cause considerable discomfort as a consequence of ulceration, oozing, bleeding and pain. Electrochemotherapy has proven to be highly effective in the treatment of cutaneous metastases. Electrochemotherapy utilises pulses of electricity to increase the permeability of the cell membrane and thereby augment the effect of chemotherapy. For the drug bleomycin, the effect is enhanced several hundred-fold, enabling once-only treatment. The primary endpoint of this study is to evaluate the efficacy of electrochemotherapy as a palliative treatment. Methods. This phase II study is a collaboration between two centres, one in Denmark and the other in the UK. Patients with cutaneous metastases of any histology were included. Bleomycin was administered intratumourally or intravenously followed by application of electric pulses to the tumour site. Results. Fifty-two patients were included. Complete and partial response rate was 68% and 18%, respectively, for cutaneous metastases <3 cm and 8% and 23%, respectively, for cutaneous metastases >3 cm. Treatment was well-tolerated by patients, including the elderly, and no serious adverse events were observed. Conclusions. ECT is an efficient and safe treatment and clinicians should not hesitate to use it even in the elderly
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
A framework for secondary cognitive and motor tasks in dual-task gait testing in people with mild cognitive impairment
Background: Cognition is a key factor in the regulation of normal walking and dual-task gait assessment is an accepted method to evaluate the relationship. The objective of this study was to create a framework for task complexity of concurrent motor and cognitive tasks with gait in people with mild cognitive impairment (MCI).
Methods: Community-dwelling people with MCI (n = 41, mean age = 76.20 ± 7.65 years) and cognitively normal controls (n = 41, mean age = 72.10 ± 3.80 years) participated in this study. Gait velocity was collected using an instrumented walkway under one single task and six combined tasks of motor and cognitive activities. The cognitive cost was the difference between the single gait task and each of the concurrent motor and cognitive challenges. A repeated two-way measure ANOVA assessed the effect of cognitive group and walking test condition for each gait task test.
Results: Gait velocity was significantly slower in the MCI group under all tasks. For both groups, the concurrent motor task of carrying a glass of water conferred a challenge not different from the cognitive task of counting backwards by ones. Performance of the complex cognitive task of serial seven subtractions reduced gait velocity in both groups, but produced a greater change in the MCI group (31.8%).
Conclusions: Not all concurrent tasks challenge cognition-motor interaction equivalently. This study has created a framework of task difficulty which allows for the translation of dual-task test conditions to future research and clinical practice to ensure the accuracy of assessing patient deficits and risk
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