Lung adenocarcinoma promotion by air pollutants.

A complete understanding of how exposure to environmental substances promotes cancer formation is lacking. More than 70 years ago, tumorigenesis was proposed to occur in a two-step process: an initiating step that induces mutations in healthy cells, followed by a promoter step that triggers cancer development1. Here we propose that environmental particulate matter measuring ≤2.5 µm (PM2.5), known to be associated with lung cancer risk, promotes lung cancer by acting on cells that harbour pre-existing oncogenic mutations in healthy lung tissue. Focusing on EGFR-driven lung cancer, which is more common in never-smokers or light smokers, we found a significant association between PM2.5 levels and the incidence of lung cancer for 32,957 EGFR-driven lung cancer cases in four within-country cohorts. Functional mouse models revealed that air pollutants cause an influx of macrophages into the lung and release of interleukin-1ß. This process results in a progenitor-like cell state within EGFR mutant lung alveolar type II epithelial cells that fuels tumorigenesis. Ultradeep mutational profiling of histologically normal lung tissue from 295 individuals across 3 clinical cohorts revealed oncogenic EGFR and KRAS driver mutations in 18% and 53% of healthy tissue samples, respectively. These findings collectively support a tumour-promoting role for  PM2.5 air pollutants  and provide impetus for public health policy initiatives to address air pollution to reduce disease burden.

Recommendations for laboratory workflow that better support centralised amalgamation of genomic variant data: findings from CanVIG-UK national molecular laboratory survey.

BACKGROUND: National and international amalgamation of genomic data offers opportunity for research and audit, including analyses enabling improved classification of variants of uncertain significance. Review of individual-level data from National Health Service (NHS) testing of cancer susceptibility genes (2002-2023) submitted to the National Disease Registration Service revealed heterogeneity across participating laboratories regarding (1) the structure, quality and completeness of submitted data, and (2) the ease with which that data could be assembled locally for submission. METHODS: In May 2023, we undertook a closed online survey of 51 clinical scientists who provided consensus responses representing all 17 of 17 NHS molecular genetic laboratories in England and Wales which undertake NHS diagnostic analyses of cancer susceptibility genes. The survey included 18 questions relating to 'next-generation sequencing workflow' (11), 'variant classification' (3) and 'phenotypical context' (4). RESULTS: Widely differing processes were reported for transfer of variant data into their local LIMS (Laboratory Information Management System), for the formatting in which the variants are stored in the LIMS and which classes of variants are retained in the local LIMS. Differing local provisions and workflow for variant classifications were also reported, including the resources provided and the mechanisms by which classifications are stored. CONCLUSION: The survey responses illustrate heterogeneous laboratory workflow for preparation of genomic variant data from local LIMS for centralised submission. Workflow is often labour-intensive and inefficient, involving multiple manual steps which introduce opportunities for error. These survey findings and adoption of the concomitant recommendations may support improvement in laboratory dataflows, better facilitating submission of data for central amalgamation.

The effect of NK3-Saporin injection within the arcuate nucleus on puberty, the LH surge, and the response to Senktide in female sheep†.

The timing of puberty onset is reliant on increased gonadotropin-releasing hormone (GnRH). This elicits a corresponding increase in luteinizing hormone (LH) due to a lessening of sensitivity to the inhibitory actions of estradiol (E2). The mechanisms underlying the increase in GnRH release likely involve a subset of neurons within the arcuate (ARC) nucleus of the hypothalamus that contain kisspeptin, neurokinin B (NKB), and dynorphin (KNDy neurons). We aimed to determine if KNDy neurons in female sheep are critical for: timely puberty onset; the LH surge; and the response to an intravenous injection of the neurokinin-3 receptor (NK3R) agonist, senktide. Prepubertal ewes received injections aimed at the ARC containing blank-saporin (control, n = 5) or NK3-saporin (NK3-SAP, n = 6) to ablate neurons expressing NK3R. Blood samples taken 3/week for 65 days following surgery were assessed for progesterone to determine onset of puberty. Control ewes exhibited onset of puberty at 33.2 ± 3.9 days post sampling initiation, whereas 5/6 NK3-SAP treated ewes didn't display an increase in progesterone. After an artificial LH surge protocol, surge amplitude was lower in NK3-SAP ewes. Finally, ewes were treated with senktide to determine if an LH response was elicited. LH pulses were evident in both groups in the absence of injections, but the response to senktide vs saline was similar between groups. These results show that KNDy cells are necessary for timely puberty onset and for full expresson of the LH surge. The occurrence of LH pulses in NK3-SAP treated ewes may indicate a recovery from an apulsatile state.

Germline mismatch repair (MMR) gene analyses from English NHS regional molecular genomics laboratories 1996-2020: development of a national resource of patient-level genomics laboratory records.

OBJECTIVE: To describe national patterns of National Health Service (NHS) analysis of mismatch repair (MMR) genes in England using individual-level data submitted to the National Disease Registration Service (NDRS) by the NHS regional molecular genetics laboratories. DESIGN: Laboratories submitted individual-level patient data to NDRS against a prescribed data model, including (1) patient identifiers, (2) test episode data, (3) per-gene results and (4) detected sequence variants. Individualised per-laboratory algorithms were designed and applied in NDRS to extract and map the data to the common data model. Laboratory-level MMR activity audit data from the Clinical Molecular Genetics Society/Association of Clinical Genomic Science were used to assess early years' missing data. RESULTS: Individual-level data from patients undergoing NHS MMR germline genetic testing were submitted from all 13 English laboratories performing MMR analyses, comprising in total 16 722 patients (9649 full-gene, 7073 targeted), with the earliest submission from 2000. The NDRS dataset is estimated to comprise >60% of NHS MMR analyses performed since inception of NHS MMR analysis, with complete national data for full-gene analyses for 2016 onwards. Out of 9649 full-gene tests, 2724 had an abnormal result, approximately 70% of which were (likely) pathogenic. Data linkage to the National Cancer Registry demonstrated colorectal cancer was the most frequent cancer type in which full-gene analysis was performed. CONCLUSION: The NDRS MMR dataset is a unique national pan-laboratory amalgamation of individual-level clinical and genomic patient data with pseudonymised identifiers enabling linkage to other national datasets. This growing resource will enable longitudinal research and can form the basis of a live national genomic disease registry.

Germline predisposition to haematological malignancies: Best practice consensus guidelines from the UK Cancer Genetics Group (UKCGG), CanGene-CanVar and the NHS England Haematological Oncology Working Group.

The implementation of whole genome sequencing and large somatic gene panels in haematological malignancies is identifying an increasing number of individuals with either potential or confirmed germline predisposition to haematological malignancy. There are currently no national or international best practice guidelines with respect to management of carriers of such variants or of their at-risk relatives. To address this gap, the UK Cancer Genetics Group (UKCGG), CanGene-CanVar and the NHS England Haematological Oncology Working Group held a workshop over two days on 28-29th April 2022, with the aim of establishing consensus guidelines on relevant clinical and laboratory pathways. The workshop focussed on the management of disease-causing germline variation in the following genes: DDX41, CEBPA, RUNX1, ANKRD26, ETV6, GATA2. Using a pre-workshop survey followed by structured discussion and in-meeting polling, we achieved consensus for UK best practice in several areas. In particular, high consensus was achieved on issues regarding standardised reporting, variant classification, multidisciplinary team working and patient support. The best practice recommendations from this meeting may be applicable to an expanding number of other genes in this setting.

Neurocognitive and emotional factors predict pain-related healthcare utilization in children with sickle cell disease.

BACKGROUND: Youth with sickle cell disease (SCD) experience increased rates of neurocognitive and emotional difficulties. Cross-sectional studies suggest neurocognitive and emotional functioning are associated with health outcomes in SCD. We investigated whether neurocognitive and emotional factors predicted future pain-related healthcare utilization in children with SCD. PROCEDURE: Total 112 youth with SCD between ages 7 and 16 years reported sociodemographics and completed measures of neurocognitive functioning and emotional well-being. The number of emergency department (ED) visits and hospitalizations for pain 1 and 3 years after enrollment were determined by chart review. RESULTS: The mean age of participants was 10.61 years (standard deviation = 2.91), with most being female (n = 65; 58%). Eighty-three (74%) participants had either HbSS or HbSß0 thalassemia. Regression analyses showed that attention significantly predicted ED visits and hospitalizations for pain at 1 and 3 years after enrollment (all p-values ≤ .017), such that poorer attention was associated with higher healthcare utilization. Lower emotional quality of life also predicted more ED visits for pain at 3 years (b = -.009, p = .013) and hospitalizations for pain at 3 years (b = -.008, p = .020). CONCLUSIONS: Neurocognitive and emotional factors are associated with subsequent healthcare use in youth with SCD. Poor attentional control might limit implementation of strategies to distract from pain or could make disease self-management behaviors more challenging. Results also highlight the potential impact of stress on pain onset, perception, and management. Clinicians should consider neurocognitive and emotional factors when developing strategies to optimize pain-related outcomes in SCD.

Feasibility and preliminary efficacy of the Balance Program to reduce pain-related disability in pediatric sickle cell disease.

BACKGROUND: Sickle cell disease (SCD) pain is associated with functional impairment, and treatment is often limited to pharmacological approaches with unwanted side effects. Although behavioral interventions exist for non-SCD pain populations, interventions designed to address pain-related impairment in SCD are lacking. METHODS: Twenty youth (9-17 years) with SCD completed a four-week telemedicine pain intervention (NCT04388241). Participants and caregivers completed baseline and post-intervention PROMIS pain measures and the Treatment Evaluation Inventory-Short Form (TEI-SF). Descriptive analyses assessed feasibility and acceptability. Reliable Change Index analyses assessed for significant post-intervention changes in pain functioning. Paired t test analyses compared baseline and post-intervention opioid prescription fills. RESULTS: All participants completed at least one treatment session. Eighteen (90%) youth completed all sessions. Youth (100%) and caregivers (94%) rated the intervention as moderately or highly acceptable on the TEI-SF. Forty-seven percent of caregivers and 44% of youth reported reliably significant improvements in pain interference after the intervention (median T-score differences: 24.8 and 23.5, respectively). Sixty-five percent of caregivers (T-score improvement difference: 19.3) and 31% of youth (T-score improvement difference: 32) reported improvements in pain behaviors. There was no significant difference in opioid prescription fills pre- and post-intervention (P > 0.05). CONCLUSIONS: The Balance Program is feasible, highly acceptable, and can be delivered remotely to reduce barriers to care. Approximately half of youth and caregivers reported significant declines in pain interference following the intervention, with substantial improvements in functioning for treatment responders. Behavioral pain interventions are important adjunctive treatments to uniquely address functional impairment associated with acute and chronic pain in SCD.

Children's Oncology Group's 2023 blueprint for research: Behavioral science.

As survival rates for childhood cancer have improved, there has been increasing focus on identifying and addressing adverse impacts of cancer and its treatment on children and their families during treatment and into survivorship. The Behavioral Science Committee (BSC) of the Children's Oncology Group (COG), comprised of psychologists, neuropsychologists, social workers, nurses, physicians, and clinical research associates, aims to improve the lives of children with cancer and their families through research and dissemination of empirically supported knowledge. Key achievements of the BSC include enhanced interprofessional collaboration through integration of liaisons into other key committees within COG, successful measurement of critical neurocognitive outcomes through standardized neurocognitive assessment strategies, contributions to evidence-based guidelines, and optimization of patient-reported outcome measurement. The collection of neurocognitive and behavioral data continues to be an essential function of the BSC, in the context of therapeutic trials that are modifying treatments to maximize event-free survival, minimize adverse outcomes, and optimize quality of life. In addition, through hypothesis-driven research and multidisciplinary collaborations, the BSC will also begin to prioritize initiatives to expand the systematic collection of predictive factors (e.g., social determinants of health) and psychosocial outcomes, with overarching goals of addressing health inequities in cancer care and outcomes, and promoting evidence-based interventions to improve outcomes for all children, adolescents, and young adults with cancer.

Sebaceous carcinoma epidemiology, associated malignancies and Lynch/Muir-Torre syndrome screening in England from 2008 to 2018.

BACKGROUND: Sebaceous carcinomas (SC) may be associated with the cancer predisposition syndrome Muir-Torre/Lynch syndrome (MTS/LS), identifiable by SC mismatch repair (MMR) screening; however, there is limited data on MMR status of SC. OBJECTIVE: To describe the epidemiology of SC, copresentation of other cancers, and population level frequency of MMR screening in SC. METHODS: A population-based retrospective cohort study of SC patients in the National Cancer Registration and Analysis Service in England. RESULTS: This study included 1077 SC cases (739 extraocular, 338 periocular). Age-standardized incidence rates (ASIR) were higher in men compared with women, 2.74 (95% CI, 2.52-9.69) per 1,000,000 person-years for men versus 1.47 person-years (95% CI, 1.4-1.62) for women. Of the patients, 19% (210/1077) developed at least one MTS/LS-associated malignancy. MMR immunohistochemical screening was performed in only 20% (220/1077) of SC tumors; of these, 32% (70/219) of tumors were MMR deficient. LIMITATIONS: Retrospective design. CONCLUSIONS: Incorporation of MMR screening into clinical practice guidelines for the management of SC will increase the opportunity for MTS/LS diagnoses, with implications for cancer surveillance, chemoprevention with aspirin, and immunotherapy treatment targeted to MTS/LS cancers.

Cognitive Functioning and Educational Support Plans in Youth With Sickle Cell Disease.

Children with sickle cell disease (SCD) face academic challenges because of direct and indirect disease-related events. This study examined the proportion of youth with SCD with educational plans and whether cognitive functioning is associated with educational support. Ninety-one youth (7 to 16 y) with SCD completed the WISC-V; caregivers reported educational support (504 Plan/Individualized Education Program) and completed the Behavior Rating Inventory of Executive Function. χ2 square and t test analyses explored whether overall intelligence (full-scale intelligence quotient [FSIQ]), relative weaknesses in processing speed and working memory (> 1SD below FSIQ), and parent-reported executive functioning were associated with educational plans. Participants with a FSIQ<90 were more likely to have support (74%) compared with youth with a FSIQ≥90 (47%; P=0.012). Those with FSIQ≥90 and FSIQ=80 to 89 were less likely to have support (47%, 58%, respectively) compared with those with FSIQ≤79 (89%; P=0.004). Relative weaknesses in processing speed were associated with educational support (83% vs. 52%, P=0.018) as well as behavioral aspects of executive functioning (Ps<0.05). Despite universal eligibility for a 504 Plan, 42% of youth with SCD in our sample did not have educational support. Significant deficits in intellectual functioning, processing speed, and parent-observed executive functioning are associated with having a plan, but children with subtle deficits seem less likely to be identified for educational support.

A Randomized Controlled Trial of Working Memory Training in Pediatric Sickle Cell Disease.

OBJECTIVE: Youth with sickle cell disease (SCD) are at risk for neurocognitive deficits including problems with working memory (WM), but few interventions to improve functioning exist. This study sought to determine the feasibility and efficacy of home-based, digital WM training on short-term memory and WM, behavioral outcomes, and academic fluency using a parallel group randomized controlled trial design. METHODS: 47 children (7-16 years) with SCD and short-term memory or WM difficulties were randomized to Cogmed Working Memory Training at home on a tablet device (N = 24) or to a standard care Waitlist group (N = 23) that used Cogmed after the waiting period. Primary outcomes assessed in clinic included performance on verbal and nonverbal short-term memory and WM tasks. Secondary outcomes included parent-rated executive functioning and tests of math and reading fluency. RESULTS: In the evaluable sample, the Cogmed group (N = 21) showed greater improvement in visual WM compared with the Waitlist group (N = 22; p = .03, d = 0.70 [CI95 = 0.08, 1.31]). When examining a combined sample of participants, those who completed ≥10 training sessions exhibited significant improvements in verbal short-term memory, visual WM, and math fluency. Adherence to Cogmed was lower than expected (M = 9.07 sessions, SD = 7.77), with 19 participants (41%) completing at least 10 sessions. Conclusions: Visual WM, an ability commonly affected by SCD, is modifiable with cognitive training. Benefits extended to verbal short-term memory and math fluency when patients completed a sufficient training dose. Additional research is needed to identify ideal candidates for training and determine whether training gains are sustainable and generalize to real-world outcomes.

Neurocognitive and psychological effects of persistent pain in pediatric sickle cell disease.

BACKGROUND: Pain is a major complication of sickle cell disease (SCD), spanning vaso-occlusive crises and persistent pain. Although it is known that persistent pain is associated with considerable impairment in youth without SCD, little is known about the functional effects of persistent pain in SCD. The current study aimed to (a) characterize persistent pain in youth with SCD and (b) determine the extent to which youth with SCD and persistent pain differ in disease morbidity, functional impairment, and neurocognitive and psychological functioning. PROCEDURE: Eighty-nine participants (ages 7-16) and caregivers completed questionnaires (BRIEF [Behavior Rating Inventory of Executive Function], Conners-3 [Conners-third edition], and PedsQL™-SCD Module, where PedsQL is Pediatric Quality of Life Inventory). Participants completed neurocognitive tests WISC-V [Wechsler Intelligence Scale for Children-fifth edition], WJ-III [Woodcock Johnson Tests of Achievement-third edition], and WIAT-III [Wechsler Individual Achievement Test-third edition]). Youth were classified as having persistent pain if they reported daily pain for 7 days. Chi-square and independent sample t-test analyses were used to assess group differences (those with vs without persistent pain). RESULTS: Patients with persistent pain (n = 18) reported lower health-related quality of life (P = .000). Caregivers were more likely to rate youth with persistent pain as having lower planning/organization abilities (P = .011) and clinically elevated symptoms of defiance/aggression and oppositional defiance (Ps = .00; .01). Patients with persistent pain demonstrated poorer working memory (P = .023) and processing speed (P = .027), and fewer demonstrating reading fluency abilities in the average or above range (P = .026). CONCLUSIONS: Youth with SCD and persistent pain are at risk for psychosocial and neurocognitive impairments, suggesting that persistent pain may be an important indicator of disease burden. Furthermore, disease management may be enhanced by assessing cognitive and psychosocial functioning and incorporating interdisciplinary treatments addressing impairment associated with persistent pain.

Views of parents of children with sickle cell disease on pre-implantation genetic diagnosis.

Pre-implantation genetic diagnosis (PGD) is an option for parents who have a child with sickle cell disease (SCD) to have another child without SCD. We conducted a survey of 19 parents with at least one child with SCD to investigate views on PGD. Before education, 44% of parents were aware of PGD. All parents rated PGD education as important. All parents considering another child also reported interest in using PGD if insurance covered its costs. Parents who have a child with SCD appear to be interested in PGD and educational tools informing this group about PGD should be developed.

Cognitive Abilities Moderate the Effect of Disease Severity on Health-Related Quality of Life in Pediatric Sickle Cell Disease.

Objective: Complications that can arise from sickle cell disease (SCD) have the potential to negatively affect health-related quality of life (HRQL). SCD manifests in varying degrees of severity, but effects on HRQL are not uniform. Cognitive abilities influence HRQL in other pediatric groups, potentially through variability in treatment adherence and psychological coping. This study examined the effect of SCD severity on HRQL and explored cognitive abilities as a moderator of this relationship. Methods: A total of 86 children and adolescents with SCD (ages 7-16 years) completed a cognitive assessment (Wechsler Scale of Intelligence for Children, Fifth Edition), and primary caregivers rated their child's SCD severity and HRQL (PedsQL Sickle Cell Disease Module). A hierarchical linear regression was conducted to evaluate the interactive effect of SCD severity and cognitive functioning on HRQL. Results: Caregiver-rated SCD severity predicted HRQL and cognitive abilities interacted with disease severity to influence HRQL. Youth with milder SCD and cognitive abilities in the average range or higher demonstrated significantly better HRQL compared with youth with mild SCD but below average cognitive abilities. Youth with more severe disease appeared to exhibit similarly low levels of HRQL, with only a minimal influence of cognitive abilities. Conclusions: Cognitive factors modify the effect of SCD severity on HRQL, particularly among youth with milder forms of SCD. Future studies are warranted to clarify the role of cognitive abilities in determining HRQL. Clinicians should monitor youth with milder forms of SCD and limited cognitive abilities for worsening HRQL and opportunities to provide support around disease self-management.

Mutations in APOPT1, encoding a mitochondrial protein, cause cavitating leukoencephalopathy with cytochrome c oxidase deficiency.

Cytochrome c oxidase (COX) deficiency is a frequent biochemical abnormality in mitochondrial disorders, but a large fraction of cases remains genetically undetermined. Whole-exome sequencing led to the identification of APOPT1 mutations in two Italian sisters and in a third Turkish individual presenting severe COX deficiency. All three subjects presented a distinctive brain MRI pattern characterized by cavitating leukodystrophy, predominantly in the posterior region of the cerebral hemispheres. We then found APOPT1 mutations in three additional unrelated children, selected on the basis of these particular MRI features. All identified mutations predicted the synthesis of severely damaged protein variants. The clinical features of the six subjects varied widely from acute neurometabolic decompensation in late infancy to subtle neurological signs, which appeared in adolescence; all presented a chronic, long-surviving clinical course. We showed that APOPT1 is targeted to and localized within mitochondria by an N-terminal mitochondrial targeting sequence that is eventually cleaved off from the mature protein. We then showed that APOPT1 is virtually absent in fibroblasts cultured in standard conditions, but its levels increase by inhibiting the proteasome or after oxidative challenge. Mutant fibroblasts showed reduced amount of COX holocomplex and higher levels of reactive oxygen species, which both shifted toward control values by expressing a recombinant, wild-type APOPT1 cDNA. The shRNA-mediated knockdown of APOPT1 in myoblasts and fibroblasts caused dramatic decrease in cell viability. APOPT1 mutations are responsible for infantile or childhood-onset mitochondrial disease, hallmarked by the combination of profound COX deficiency with a distinctive neuroimaging presentation.

Pathogenic variants in HTRA2 cause an early-onset mitochondrial syndrome associated with 3-methylglutaconic aciduria.

Mitochondrial diseases collectively represent one of the most heterogeneous group of metabolic disorders. Symptoms can manifest at any age, presenting with isolated or multiple-organ involvement. Advances in next-generation sequencing strategies have greatly enhanced the diagnosis of patients with mitochondrial disease, particularly where a mitochondrial aetiology is strongly suspected yet OXPHOS activities in biopsied tissue samples appear normal. We used whole exome sequencing (WES) to identify the molecular basis of an early-onset mitochondrial syndrome-pathogenic biallelic variants in the HTRA2 gene, encoding a mitochondria-localised serine protease-in five subjects from two unrelated families characterised by seizures, neutropenia, hypotonia and cardio-respiratory problems. A unifying feature in all affected children was 3-methylglutaconic aciduria (3-MGA-uria), a common biochemical marker observed in some patients with mitochondrial dysfunction. Although functional studies of HTRA2 subjects' fibroblasts and skeletal muscle homogenates showed severely decreased levels of mutant HTRA2 protein, the structural subunits and complexes of the mitochondrial respiratory chain appeared normal. We did detect a profound defect in OPA1 processing in HTRA2-deficient fibroblasts, suggesting a role for HTRA2 in the regulation of mitochondrial dynamics and OPA1 proteolysis. In addition, investigated subject fibroblasts were more susceptible to apoptotic insults. Our data support recent studies that described important functions for HTRA2 in programmed cell death and confirm that patients with genetically-unresolved 3-MGA-uria should be screened by WES with pathogenic variants in the HTRA2 gene prioritised for further analysis.

A recurrent mitochondrial p.Trp22Arg NDUFB3 variant causes a distinctive facial appearance, short stature and a mild biochemical and clinical phenotype.

BACKGROUND: Isolated Complex I deficiency is the most common paediatric mitochondrial disease presentation, associated with poor prognosis and high mortality. Complex I comprises 44 structural subunits with at least 10 ancillary proteins; mutations in 29 of these have so far been associated with mitochondrial disease but there are limited genotype-phenotype correlations to guide clinicians to the correct genetic diagnosis. METHODS: Patients were analysed by whole-exome sequencing, targeted capture or candidate gene sequencing. Clinical phenotyping of affected individuals was performed. RESULTS: We identified a cohort of 10 patients from 8 families (7 families are of unrelated Irish ancestry) all of whom have short stature (<9th centile) and similar facial features including a prominent forehead, smooth philtrum and deep-set eyes associated with a recurrent homozygous c.64T>C, p.Trp22Arg NDUFB3 variant. Two sibs presented with primary short stature without obvious metabolic dysfunction. Analysis of skeletal muscle from three patients confirmed a defect in Complex I assembly. CONCLUSIONS: Our report highlights that the long-term prognosis related to the p.Trp22Arg NDUFB3 mutation can be good, even for some patients presenting in acute metabolic crisis with evidence of an isolated Complex I deficiency in muscle. Recognition of the distinctive facial features-particularly when associated with markers of mitochondrial dysfunction and/or Irish ancestry-should suggest screening for the p.Trp22Arg NDUFB3 mutation to establish a genetic diagnosis, circumventing the requirement of muscle biopsy to direct genetic investigations.

Sudden adult death syndrome in m.3243A>G-related mitochondrial disease: an unrecognized clinical entity in young, asymptomatic adults.

AIMS: To provide insight into the mechanism of sudden adult death syndrome (SADS) and to give new clinical guidelines for the cardiac management of patients with the most common mitochondrial DNA mutation, m.3243A>G. These studies were initiated after two young, asymptomatic adults harbouring the m.3243A>G mutation died suddenly and unexpectedly. The m.3243A>G mutation is present in ∼1 in 400 of the population, although the recognized incidence of mitochondrial DNA (mtDNA) disease is ∼1 in 5000. METHODS AND RESULTS: Pathological studies including histochemistry and molecular genetic analyses performed on various post-mortem samples including cardiac tissues (atrium and ventricles) showed marked respiratory chain deficiency and high levels of the m.3243A>G mutation. Systematic review of cause of death in our m.3243A>G patient cohort showed the person-time incidence rate of sudden adult death is 2.4 per 1000 person-years. A further six cases of sudden death among extended family members have been identified from interrogation of family pedigrees. CONCLUSION: Our findings suggest that SADS is an important cause of death in patients with m.3243A>G and likely to be due to widespread respiratory chain deficiency in cardiac muscle. The involvement of asymptomatic relatives highlights the importance of family tracing in patients with m.3243A>G and the need for specific cardiac arrhythmia surveillance in the management of this common genetic disease. In addition, these findings have prompted the derivation of cardiac guidelines specific to patients with m.3243A>G-related mitochondrial disease. Finally, due to the prevalence of this mtDNA point mutation, we recommend inclusion of testing for m.3243A>G mutations in the genetic autopsy of all unexplained cases of SADS.

Characterization of acinar airspace involvement in asthmatic patients by using inert gas washout and hyperpolarized (3)helium magnetic resonance.

BACKGROUND: The multiple-breath inert gas washout parameter acinar ventilation heterogeneity (Sacin) is thought to be a marker of acinar airway involvement but has not been validated by using quantitative imaging techniques in asthmatic patients. OBJECTIVE: We aimed to use hyperpolarized (3)He diffusion magnetic resonance at multiple diffusion timescales and quantitative computed tomographic (CT) densitometry to determine the nature of acinar airway involvement in asthmatic patients. METHODS: Thirty-seven patients with asthma and 17 age-matched healthy control subjects underwent spirometry, body plethysmography, multiple-breath inert gas washout (with the tracer gas sulfur hexafluoride), and hyperpolarized (3)He diffusion magnetic resonance. A subset of asthmatic patients (n = 27) underwent quantitative CT densitometry. RESULTS: Ninety-four percent (16/17) of patients with an increased Sacin had Global Initiative for Asthma treatment step 4 to 5 asthma, and 13 of 17 had refractory disease. The apparent diffusion coefficient (ADC) of (3)He at 1 second was significantly higher in patients with Sacin-high asthma compared with that in healthy control subjects (0.024 vs 0.017, P < .05). Sacin correlated strongly with ADCs at 1 second (R = 0.65, P < .001) but weakly with ADCs at 13 ms (R = 0.38, P < .05). ADCs at both 13 ms and 1 second correlated strongly with the mean lung density expiratory/inspiratory ratio, a CT marker of expiratory air trapping (R = 0.77, P < .0001 for ADCs at 13 ms; R = 0.72, P < .001 for ADCs at 1 second). CONCLUSION: Sacin is associated with alterations in long-range diffusion within the acinar airways and gas trapping. The precise anatomic nature and mechanistic role in patients with severe asthma requires further evaluation.

Feasibility of Home-Based Computerized Working Memory Training With Children and Adolescents With Sickle Cell Disease.

BACKGROUND: Children with sickle cell disease (SCD) are at increased risk for neurocognitive deficits, yet the literature describing interventions to ameliorate these problems and promote academic achievement is limited. We evaluated the feasibility and preliminary efficacy of a home-based computerized working memory (WM) training intervention (Cogmed) in children with SCD. PROCEDURE: Youth with SCD between the age of 7 and 16 years completed an initial neuropsychological assessment; those with WM deficits were loaned an iPad on which they accessed Cogmed at home. Participants were instructed to work on Cogmed 5 days each week for 5 weeks (25 training sessions). We examined Cogmed usage characteristics and change on WM assessment scores following the intervention. RESULTS: Of the 21 participants (M age = 11.38, SD = 2.78; Mdn age = 10.00, interquartile range [IQR] = 5.00; 52% female) screened, 60% exhibited WM deficits (n = 12) and received the intervention and 50% (n = 6) completed Cogmed. The mean number of sessions completed was 15.83 (SD = 7.73; Mdn = 17.00, IQR = 16.00); females were more likely to complete Cogmed, χ(2) (1) = 6.00, P = 0.01. Participants who reported lower SCD-related pain impact completed more sessions (r = 0.71, P = 0.01). Children who completed Cogmed exhibited improvements in verbal WM, visuospatial short-term memory, and visuospatial WM. CONCLUSIONS: Initial findings suggest Cogmed is associated with WM improvement in youth with SCD; however, adherence was lower than expected. Home-based WM interventions may ameliorate SCD-related WM deficits but strategies are needed to address barriers to program completion.