Establishment of Advanced Regulatory Innovation for Clinical Trials Transformation (ARICTT): a multi-stakeholder public-private partnership-based organization to accelerate the transformation of clinical trials

Clinical trials have evolved with digital technologies and tend towards patient-centricity. A multi-stakeholder approach is needed to address the emerging complexities in clinical trials. In particular, the introduction of digital technologies and an emphasis on patient-centricity are the major trends in clinical trials. In response, we established a public-private partnership-based organization named Advanced Regulatory Innovation for Clinical Trials Transformation (ARICTT). Eleven organizations in total, from academia, industry, and regulatory agencies, participate in ARICTT. Based on multi-stakeholder collaboration from academia, industry, and government/regulatory bodies, we collected and prioritized current topics in clinical trials based on an internal survey. We established a three-year roadmap with axes that were termed trend, goal, structure, theme, topic, and method. In addition, we planned the development of recommendations based on real-world cases with feasibility studies. We developed appropriate organizational structure to fulfill the roadmap of ARICTT. The selected topics were decentralized clinical trials during the first year, followed by the three topics that were awarded the highest priority according to the internal survey: advances in the informed consent process, supporting sites using digital technology, and an effective recruitment strategy. We developed a case-based recommendation paper presenting an overview of the regulatory landscape and practical considerations with explanatory cases. We also designed and conducted fully decentralized trials to evaluate considerations in real-world settings for the selected topics. Overall engagement and communication were supported by the online platform and annual symposiums. In conclusion, we established a multi-stakeholder, public-private partnership-based organization to accelerate the transformation of clinical trials.

Safety, Tolerability, and Pharmacokinetics of a Novel Macrocyclic Gadolinium-Based Contrast Agent, HNP-2006, in Healthy Subjects

OBJECTIVES

Gadolinium-based contrast agents (GBCAs) are indispensable in contrast-enhanced magnetic resonance imaging. A higher risk of gadolinium deposition in linear GBCAs required the introduction of macrocyclic GBCAs with a stable molecular structure. We conducted the first-in-human study to evaluate the safety, tolerability, and pharmacokinetics (PKs) of HNP-2006, a novel macrocyclic GBCA, in healthy male subjects.

MATERIALS AND METHODS

A randomized, placebo-controlled, double-blind, single-ascending dose study was conducted. Subjects received either a single intravenous bolus injection of HNP-2006 or its matching placebo with a treatment-to-placebo ratio of 6:2 at the dose level of 0.02, 0.05, 0.1, 0.2, and 0.3 mmol/kg. Safety was assessed through routine clinical assessments. Blood sampling and urine collection were performed up to 72 hours postdose for PK assessments. Noncompartmental methods were used to calculate PK parameters, and a population PK model was constructed.

RESULTS

Overall, 40 subjects completed the study. Fourteen subjects reported 22 treatment-emergent adverse events (TEAEs). The severity of all TEAEs was mild, and the HNP-2006 dose was associated with the incidence of TEAEs. The most common TEAEs included nausea and dizziness, which occurred within an hour of administration. HNP-2006 was rapidly eliminated by urinary excretion with a half-life of 1.8-2.0 hours and showed a dose-proportional PK. A 2-compartment model had the best fit with the population PK analysis.

CONCLUSIONS

A single intravenous dose of HNP-2006 was well-tolerated and safe up to 0.30 mmol/kg. HNP-2006 was rapidly excreted in urine and exhibited dose-independent PK profiles.

The landscape of decentralized clinical trials (DCTs): focusing on the FDA and EMA guidance

Decentralized clinical trials (DCTs) consist of off-site trial-related procedures referred to as decentralized elements. We aimed to provide an overview of the landscape of DCTs by comparing regulatory guidance reports and analyzing decentralized elements from clinical trial registries. Two guidance reports on DCTs published by the U.S. Food and Drug Administration and the European Medicines Agencies were summarized and analyzed. Both guidance publications commonly emphasized an assessment of the appropriateness of decentralized elements along 2 axes: patient safety and data integrity. DCT cases were identified from ClinicalTrials.gov by searching with 6 keywords: decentralized, remote, mobile, digital, virtual, and hybrid. Cases where the keyword was used in a non-DCT context, such as digital flexor tendon, were excluded by means of natural language processing. A total of 4,874 trials were identified as DCT cases, with annual increases, especially after 2020. The most common keywords were 'mobile' and 'digital' (36.2% and 24.8%, respectively). Interventions in the DCT cases were analyzed by means of a network analysis. Behavioral and technological tokens were frequently combined, such as 'rehabilitation' and 'app.' Drugs were used in only 1.8% of the DCT cases. Of these, most drugs had been approved previously (96.8%) and were in oral formulation (67.2%). Most of the DCT cases identified in this study involved simple interventions and low-risk drugs. These characteristics were in accordance with the common recommendations in the DCT guidance publications.

Evaluation of Food Effect on the Pharmacokinetics of Velufenacin, a New Muscarinic Receptor Antagonist, in Healthy Subjects

Velufenacin (DA-8010) is a new muscarinic receptor antagonist under development for the treatment of overactive bladder. This study aimed to evaluate the effect of food on the pharmacokinetics (PK) and safety of velufenacin in healthy subjects. A randomized, open-label, single-dose, 4-sequence, 4-treatment, 4-period crossover study was conducted. Subjects received a single oral dose of velufenacin 2.5 or 5 mg in a fasted or fed (high-fat meal) state in each period with a 7-day washout. PK parameters including maximum plasma concentration (Cmax ) and area under the concentration-time curve from time 0 to the last measurable point were compared between the fed and fasted states. Twenty-seven subjects completed the study. The mean area under the concentration-time curve from time 0 to the last measurable point of the velufenacin 2.5 and 5 mg doses under the fed condition showed a 1.5- and 1.3-fold increase, respectively, compared to the fasted condition. The corresponding values for Cmax were a 2.3- and 2.0-fold increase, respectively. The time to reach Cmax was comparable regardless of the dose or food intake, showing median values of 4.5-5.0 hours. These results suggest a modest increase of velufenacin absorption by food intake. Velufenacin was generally safe and well tolerated at the 2.5 and 5 mg doses regardless of food.

Feasibility study for a fully decentralized clinical trial in participants with functional constipation symptoms

Decentralized clinical trials (DCTs) leverage digital technologies to reduce dependency on study sites and intermediaries. DCT should be balanced with accessibility and data reliability while meeting regulatory requirements. Here, we conducted a pilot study for functional constipation symptoms to investigate the feasibility of DCT. The study was an open, fully remote, randomized clinical trial in participants who had functional constipation symptoms. Electronic consent was obtained remotely, and study volunteers were screened through web-based questionnaires. Subjects were randomized to either receive Lactobacillus and vitamin C supplements or vitamin C alone in a 1:1 ratio, which were delivered directly to subjects. Subjects kept track of bowel diaries daily during the 1-week baseline and 2-week treatment period using mobile applications. Bowel symptoms and the validity of the records were descriptively evaluated. A total of 30 subjects were randomized and completed the study. A total of 26.7% of subjects resided outside of the metropolitan area. Two-week Lactobacillus treatments increased the number of defecations (+0.80 vs. +0.46 times per week) and decreased the defecation time (-3.94 h vs. -1.62 h) compared to the comparator group. Overall, 67.1% of bowel diary records were completed in accordance with the schedule whereas 32.9% were not. Implementation of DCTs can facilitate geographic accessibility but should be guaranteed for data reliability. Prompt detection of errors and response using objective metrics would be required.

[Genetic counselling and testing in pulmonary arterial hypertension - A consensus statement on behalf of the International Consortium for Genetic Studies in PAH - French version]

Pulmonary arterial hypertension (PAH) is a rare disease that can be caused by (likely) pathogenic germline genomic variants. In addition to the most prevalent disease gene, BMPR2 (bone morphogenetic protein receptor 2), several genes, some belonging to distinct functional classes, are also now known to predispose to the development of PAH. As a consequence, specialist and non-specialist clinicians and healthcare professionals are increasingly faced with a range of questions regarding the need for, approaches to and benefits/risks of genetic testing for PAH patients and/or related family members. We provide a consensus-based approach to recommendations for genetic counselling and assessment of current best practice for disease gene testing. We provide a framework and the type of information to be provided to patients and relatives through the process of genetic counselling, and describe the presently known disease causal genes to be analysed. Benefits of including molecular genetic testing within the management protocol of patients with PAH include the identification of individuals misclassified by other diagnostic approaches, the optimisation of phenotypic characterisation for aggregation of outcome data, including in clinical trials, and importantly through cascade screening, the detection of healthy causal variant carriers, to whom regular assessment should be offered.

Risk improvement and adverse kidney outcomes in patients with chronic kidney disease: findings from KNOW-CKD

BACKGROUND

Many trials have attempted to slow the progression of chronic kidney disease (CKD) by modifying specific risk factors, but without achieving satisfactory results. We aimed to evaluate the association between the degree of improvement in multiple risk factors and adverse kidney outcomes.

METHODS

This was a prospective observational study of 839 patients with CKD G3-G4. The main predictors were the number of improved risk factors between baseline and year one as follows: a decrease in proteinuria, systolic blood pressure, phosphate, and uric acid, and an increase in hemoglobin and bicarbonate from the baseline status to out of the target range. The primary outcome was a composite one, including CKD progression (50% decline in eGFR or kidney replacement therapy) and all-cause death.

RESULTS

Patients whose risk factors eventually improved had more unfavorable baseline profiles of the six considered factors. During 3097.8 person-years of follow-up (median 3.5 years per patient), the composite outcome occurred in 48.0% of patients (incidence rate, 13.0 per 100 person-years). Compared with an improvement of no risk factors, the adjusted HRs (95% CI) for improvement of 1 and ≥ 2 risk factors were 0.96 (0.76-1.22) and 0.53 (0.37-0.75), respectively. The association was not affected by diabetic status or CKD severity. Among the risk factors, proteinuria accounted for the greatest contribution to CKD progression.

CONCLUSIONS

In patients with CKD G3-G4, improvement in multiple factors was associated with a decreased risk of CKD progression, suggesting the importance of multifactorial risk management.

Pharmacokinetics, safety and tolerability of valbenazine in Korean CYP2D6 normal and intermediate metabolizers

Valbenazine is a selective vesicular monoamine transporter 2 (VMAT2) inhibitor approved for tardive dyskinesia treatment by the US Food and Drug Administration; its major active metabolite (NBI-98782) is a 45-fold more potent inhibitor of VMAT2 than the parent drug. This study aimed to evaluate the pharmacokinetics (PKs), safety, and tolerability and the effect of cytochrome P450 2D6 (CYP2D6) genotypes to the PKs after the administration of valbenazine in Korean participants. A randomized, double-blind, placebo-controlled, single- and multiple-dose study was conducted in healthy Korean male participants. The single-dose study was conducted for both 40 and 80 mg valbenazine and the multiple dose study was conducted for 40 mg. After a 1-week washout, the 40 mg dose group participants received valbenazine 40 mg or placebo once daily for 8 days. Serial blood samples were collected up to 96 h postdose for PK analysis. The CYP2D6 genotypes of the participants were retrospectively analyzed. A total of 50 participants were randomized, and 43 and 20 participants completed the single- and multiple-dose phases of the study, respectively. After single doses, the PK characteristics of valbenazine and its metabolites were similar between the 40 and 80 mg dose groups. After multiple doses, the mean accumulation ratios of valbenazine and NBI-98782 were ~1.6 and 2.4, respectively. Plasma concentrations of valbenazine and NBI-98782 were similar between CYP2D6 normal and intermediate metabolizers. Valbenazine was well-tolerated in healthy Koreans, and its PK characteristics were similar to results previously reported in Americans.

Being small for gestational age is not an independent risk factor for mortality in neonates with congenital diaphragmatic hernia: a multicenter study

BACKGROUND

Congenital diaphragmatic hernia (CDH) accounts for 8% of all major congenital anomalies. Neonates who are small for gestational age (SGA) generally have a poorer prognosis. We sought to identify risk factors and variables associated with outcomes in neonates with CDH who are SGA in comparison to neonates who are appropriate for gestational age (AGA).

METHODS

We used the multicenter Diaphragmatic Hernia Research & Exploration Advancing Molecular Science (DHREAMS) study to include neonates enrolled from 2005 to 2019. Chi-squared or Fisher's exact tests were used to compare categorical variables and t tests or Wilcoxon rank sum for continuous variables. Cox model analyzed time to event outcomes and logistic regression analyzed binary outcomes.

RESULTS

589 neonates were examined. Ninety were SGA (15.3%). SGA patients were more likely to be female (p = 0.003), have a left sided CDH (p = 0.05), have additional congenital anomalies and be diagnosed with a genetic syndrome (p < 0.001). On initial single-variable analysis, SGA correlated with higher frequency of death prior to discharge (p < 0.001) and supplemental oxygen requirement at 28 days (p = 0.005). Twice as many SGA patients died before repair (12.2% vs 6.4%, p = 0.04). Using unadjusted Cox model, the risk of death prior to discharge among SGA patients was 1.57 times the risk for AGA patients (p = 0.029). There was no correlation between SGA and need for ECMO, pulmonary hypertensive medication at discharge or oxygen at discharge. After adjusting for confounding variables, SGA no longer correlated with mortality prior to discharge or incidence of unrepaired defects but remained significant for oxygen requirement at 28 days (p = 0.03).

CONCLUSION

Infants with CDH who are SGA have worse survival and poorer lung function than AGA infants. However, the outcome of SGA neonates is impacted by other factors including gestational age, genetic syndromes, and particularly congenital anomalies that contribute heavily to their poorer prognosis.

Concomitant Mitochondrial Diabetes and Myopathy Mistook for Complications of Immunosuppressants After Kidney Transplant

Posttransplant diabetes mellitus, presenile deafness, and myopathy are not commonly accompanied symptoms after kidney transplant. We report the case of a 48-year-old woman with diabetes mellitus, sensorineural hearing loss, and severe myopathy without neuropathy after deceased donor kidney transplant. ShehadamitochondrialDNApointmutation at position 3243 (A>G), and mitochondrial diseases such as maternally inherited diabetes deafness or mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodeswere suspected.Diabetes andother symptoms following kidney transplant can often be overlooked as complications of immunosuppressants taken after kidney transplant. However, in patients without a known cause of their symptoms, appropriate examinations and consultation for other diseases, including genetic diseases, should be considered.

Racial and Ethnic Differences in BRCA1/2 and Multigene Panel Testing Among Young Breast Cancer Patients

Genetic testing for hereditary breast and ovarian cancer (HBOC) is recommended for breast cancer patients diagnosed at age ≤ 50 years. Our objective was to examine racial/ethnic differences in genetic testing frequency and results among diverse breast cancer patients. A retrospective cohort study among women diagnosed with breast cancer at age ≤ 50 years from January 2007 to December 2017 at Columbia University in New York, NY. Among 1503 diverse young breast cancer patients, nearly half (46.2%) completed HBOC genetic testing. Genetic testing completion was associated with younger age, family history of breast cancer, and earlier stage, but not race/ethnicity or health insurance status. Blacks had the highest frequency of pathogenic/likely pathogenic (P/LP) variants (18.6%), and Hispanics and Asians had the most variants of uncertain significance (VUS), 19.0% and 21.9%, respectively. The percentage of women undergoing genetic testing increased over time from 15.3% in 2007 to a peak of 72.8% in 2015. Over the same time period, there was a significant increase in P/LP and VUS results. Due to uncertainty about the clinical implications of P/LP variants in moderate penetrance genes and VUSs, our findings underscore the need for targeted genetic counseling education, particularly among young minority breast cancer patients.

The association of BMI and physical activity on acetabular dysplasia in children

BACKGROUND

Acetabular dysplasia is an important pre-disposing factor for osteoarthritis of the hip. However, it is not completely known how acetabular dysplasia develops during childhood.

OBJECTIVE

To study the prevalence of acetabular dysplasia and its association with body mass index (BMI) and physical activity in 9 year old children.

DESIGN

The population for this cross-sectional study was drawn from the ongoing prospective cohort study: Generation R. 9,778 mothers with a delivery date from March 2002 until January 2006 were enrolled. In a random subgroup of these children Dual-energy X-ray absorptiometry (DXA) scanning was performed at age 9.

EXPOSURES

BMI, standardized for the Dutch population and categorized in four groups based on extended international Obesity Task Force cut-offs: underweight, normal, overweight and obesity. Physical activity was based on time spent on playing outdoors, playing sports and walking/cycling to school.

MAIN OUTCOMES AND MEASURES

The degree of acetabular dysplasia was determined with the centre-edge angle (CEA) and acetabular depth-width ratio (ADR) in DXA images of the hip.

RESULTS

1,188 DXA images of children's hips were available for analysis. The median age of the children was 9.86 years. Prevalence of dysplasia and mild dysplasia was respectively 6.3%; 25.6% with CEA and 4.8%; 25.0% with ADR. BMI was negatively associated with mild dysplasia (OR 0.80 CI 0.71-0.90). Obese children showed less mild dysplasia compared to normal children (OR 0.48 CI 0.24-0.97) in unadjusted analysis. Physical activity represented by walking to school showed a statistically significant negative association with mild dysplasia (OR 0.87 CI 0.76-0.99). After adjustment for age, ethnicity, sex, first born, breech presentation, birthweight, gestational age and Caesarean section, the patterns of association with dysplasia remained for both BMI and physical activity.

CONCLUSIONS

In this study, being overweight and light physical activity were negatively associated with the development of (mild) acetabular dysplasia at the age of 9 years.

ORE identifies extreme expression effects enriched for rare variants

MOTIVATION

Non-coding rare variants (RVs) may contribute to Mendelian disorders but have been challenging to study due to small sample sizes, genetic heterogeneity and uncertainty about relevant non-coding features. Previous studies identified RVs associated with expression outliers, but varying outlier definitions were employed and no comprehensive open-source software was developed.

RESULTS

We developed Outlier-RV Enrichment (ORE) to identify biologically-meaningful non-coding RVs. We implemented ORE combining whole-genome sequencing and cardiac RNAseq from congenital heart defect patients from the Pediatric Cardiac Genomics Consortium and deceased adults from Genotype-Tissue Expression. Use of rank-based outliers maximized sensitivity while a most extreme outlier approach maximized specificity. Rarer variants had stronger associations, suggesting they are under negative selective pressure and providing a basis for investigating their contribution to Mendelian disorders.

AVAILABILITY AND IMPLEMENTATION

ORE, source code, and documentation are available at https://pypi.python.org/pypi/ore under the MIT license.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Abstract P5-09-01: Racial/ethnic differences in BRCA1/2 and multigene panel testing among young breast cancer patients

Background: Breast cancer (BC) patients diagnosed at age 50 and under are recommended to have germline genetic testing for hereditary BC due to a high likelihood of carrying a pathogenic mutation in a moderate or high penetrance risk gene. Completion of genetic testing among racial/ethnic minorities, particularly multigene panel testing, is understudied. We examined predictors of completion of BRCA1/2 and multigene panel testing among women with early onset BC and assessed racial/ethnic differences in genetic testing completion and results.

Methods: We performed a retrospective cohort study of 1370 BC patients diagnosed at &lt;50 years of age at Columbia University Medical Center (CUMC) from January 2007-December 2016.Data on socio-demographics, clinical factors, and genetic testing completion and results were collected from the medical record. We conducted descriptive statistics and univariate and multivariable logistic regression models.

Results: Our study population had a median age of 44 years (range, 19-50); 44% non-Hispanic white, 24% Hispanic, 13% non-Hispanic black, 10% Asian, 9% other; 61% private insurance, 22% Medicaid, 17% other. Nearly half of the women (N=607; 44.3%) had genetic testing performed. In the multivariable regression model, genetic testing completion was less likely with increasing age at diagnosis (odds ratio [OR]=0.93; 95% confidence interval [CI]=0.91-0.95) and stage 0 or 4 BC compared to stage 1 (OR=0.67; 95% CI=0.46-0.97 and OR=0.35; 95% CI=0.19-0.64, respectively). Completion of genetic testing was more likely with a family history of BC (OR=5.55; 95% CI=3.92-7.87). Genetic testing completion did not vary by race/ethnicity or insurance coverage. Across all racial/ethnic groups, the frequency of pathogenic/likely pathogenic variants identified was 13.0% and 10.5% had at least 1 variant of uncertain significance (VUS). The highest VUS frequency was among Asians (21.2%). The percentage of women undergoing genetic testing increased over time from 18.5% in 2007 and reached a peak of 69.3% in 2015. From 2007 to 2016, the percentage of pathogenic/likely pathogenic variants detected increased from 3.4% to 9.1% and the VUS frequency rose from 3.4% to 13.3% with increasing use of panel testing.

Frequency of pathogenic variants and VUS among women ≤ 50 years diagnosed with BC at CUMC (2007-2016) Pathogenic variantsVUSTotal81 (5.9%)74 (5.4%)BRCA144 (3.2%)10 (0.7%)BRCA221 (1.5%)10 (0.7%)ATM3 (0.2%)9 (0.6%)CHEK23 (0.2%)8 (0.5%)Other variants detected in: APC, BARD1, BRIP1, CDH1, CDKN2A, MEN1, MLH1, MRE11A, MSH2, MSH6, MUTYH, NBN, NF1, PALB2, PHOX2B, PMS2, POLE, PTEN, RAD50, RAD51C, SDHA, STK11, TP53

Conclusions and Relevance: Nearly half of the women with early onset BC had genetic testing. We did not observe disparities in genetic testing by race/ethnicity or insurance coverage. Genetic testing completion, as well as the frequency of pathogenic/likely pathogenic variants and VUS detection, increased over time as panel testing replaced BRCA1/2 testing. Counseling on the likelihood of obtaining uncertain results should be provided to all patients undergoing hereditary BC genetic testing, particularly to racial/ethnic minorities.

Citation Format: Trivedi MS, Jones T, Jiang X, Underhill ML, Bose S, Silverman T, Chung WK, Kukafka R, Crew KD. Racial/ethnic differences in BRCA1/2 and multigene panel testing among young breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-09-01.

Alpha galactosidase A activity in Parkinson's disease

Glucocerebrosidase (GCase, deficient in Gaucher disease) enzymatic activity measured in dried blood spots of Parkinson's Disease (PD) cases is within healthy range but reduced compared to controls. It is not known whether activities of additional lysosomal enzymes are reduced in dried blood spots in PD. To test whether reduction in lysosomal enzymatic activity in PD is specific to GCase, we measured GCase, acid sphingomyelinase (deficient in Niemann-Pick disease types A and B), alpha galactosidase A (deficient in Fabry), acid alpha-glucosidase (deficient in Pompe) and galactosylceramidase (deficient in Krabbe) enzymatic activities in dried blood spots of PD patients (n = 648) and controls (n = 317) recruited from Columbia University. Full sequencing of glucocerebrosidase (GBA) and the LRRK2 G2019S mutation was performed. Enzymatic activities were compared between PD cases and controls using t-test and regression models adjusted for age, gender, and GBA and LRRK2 G2019S mutation status. Alpha galactosidase A activity was lower in PD cases compared to controls both when only non-carriers were included (excluding all GBA and LRRK2 G2019S carriers and PD cases with age-at-onset below 40) [2.85 μmol/l/h versus 3.12 μmol/l/h, p = 0.018; after controlling for batch effect, p = 0.006 (468 PD cases and 296 controls)], and when including the entire cohort (2.89 μmol/l/h versus 3.10 μmol/l/h, p = 0.040; after controlling for batch effect, p = 0.011). Because the alpha galactosidase A gene is X-linked, we stratified the analyses by sex. Among women who were non-carriers of GBA and LRRK2 G2019S mutations (PD, n = 155; control, n = 194), alpha galactosidase A activity was lower in PD compared to controls (2.77 μmol/l/h versus 3.10 μmol/l/h, p = 0.044; after controlling for a batch effect, p = 0.001). The enzymatic activity of acid sphingomyelinase, acid alpha-glucosidase and galactosylceramidase was not significantly different between PD and controls. In non-carriers, most lysosomal enzyme activities were correlated, with the strongest association in GCase, acid alpha-glucosidase, and alpha galactosidase A (Pearson correlation coefficient between 0.382 and 0.532). In a regression model with all five enzymes among non-carriers (adjusted for sex and age), higher alpha galactosidase A activity was associated with lower odds of PD status (OR = 0.54; 95% CI:0.31-0.95; p = 0.032). When LRRK2 G2019S PD carriers (n = 37) were compared to non-carriers with PD, carriers had higher GCase, acid sphingomyelinase and alpha galactosidase A activity. We conclude that alpha galactosidase A may have a potential independent role in PD, in addition to GCase.

Suspected Frequent Relapsing IgG4-related Lung Disease in Kidney Transplant Patient: A Case Report

Besides the initial description of IgG4-related pancreatic disease, other sites are now commonly involved. However, occurrence of IgG4-related disease is rare in organ transplanted patients. A 57-year-old man who received a kidney transplantation presented with recurrent dyspnea on exertion. A computed tomography scan of the chest revealed bilateral interlobular septal thickening and multiple tubular and branching small nodular lesions in the right upper lobe, and mass-like consolidation of the left middle lobe. Despite no elevation of serum IgG4 level, a percutaneous core needle biopsy on consolidative mass showed interstitial fibrosis and infiltration of IgG4-positive plasma cells to be more than > 20 per high power field. After treatment with glucocorticoids and rituximab, the consolidative mass of the left middle lobe disappeared.

Diagnostic exome sequencing in children: A survey of parental understanding, experience and psychological impact

Clinical exome sequencing (CES) is increasingly being used as an effective diagnostic tool in the field of pediatric genetics. We sought to evaluate the parental experience, understanding and psychological impact of CES by conducting a survey study of English-speaking parents of children who had diagnostic CES. Parents of 192 unique patients participated. The parent's interpretation of the child's result agreed with the clinician's interpretation in 79% of cases, with more frequent discordance when the clinician's interpretation was uncertain. The majority (79%) reported no regret with the decision to have CES. Most (65%) reported complete satisfaction with the genetic counseling experience, and satisfaction was positively associated with years of genetic counselor (GC) experience. The psychological impact of CES was greatest for parents of children with positive results and for parents with anxiety or depression. The results of this study are important for helping clinicians to prepare families for the possible results and variable psychological impact of CES. The frequency of parental misinterpretation of test results indicates the need for additional clarity in the communication of results. Finally, while the majority of patients were satisfied with their genetic counseling, satisfaction was lower for new GCs, suggesting a need for targeted GC training for genomic testing.

Abstract P4-06-19: Understanding factors associated with uptake of BRCA genetic testing among Orthodox Jewish women using a mixed-methods approach

Background: The prevalence of BRCA1/2 mutations among Ashkenazi Jews is 1 in 40. Compared to family history-based BRCA testing, population-based testing has been shown to detect more mutation carriers in this population. Orthodox Jews (OJ) are the largest and fastest-growing Jewish population in NY and represent a spectrum of observance including Modern Orthodox, Yeshivish, and Chassidic. This understudied population has unique social, cultural, and religious factors that may influence BRCA genetic testing. We examined factors influencing BRCA genetic testing decision-making and uptake among OJ women.

Methods: Using a mixed-methods approach, we conducted a cross-sectional online survey and 4 focus groups among OJ women in 5 communities in the NY/NJ area. The online survey included items on demographics, breast cancer risk factors, and validated measures of genetic testing intention/knowledge, breast cancer worry/risk perception, stigma, and religious/cultural factors affecting medical decision-making. Descriptive statistics and bivariate and multivariable logistic regression models were conducted. We conducted 4 focus groups with purposive sampling of women who responded to the survey. The qualitative analysis of the semi-structured focus group discussions further explored factors affecting BRCA genetic testing uptake.

Results: Among 321 evaluable survey participants, median age was 47 years (range, 25-82); 55.8% were Modern Orthodox, 30.5% Yeshivish, and 2.8% Chassidic; 84% were married; 6.2% and 0.6% had a history of breast and ovarian cancer, respectively. Although 57.6% had a masters or doctoral degree, only 37.7% had adequate genetic testing knowledge. Nearly 20% of the surveyed women had undergone BRCA genetic testing. After adjusting for known confounders, women who met family history criteria for BRCA genetic testing were nearly 10 times more likely to undergo genetic testing. Modern Orthodox compared to non-Modern Orthodox women and married compared to unmarried women were more likely to undergo genetic testing (odds ratio [OR]=2.31, 95% confidence interval [CI]=1.03-5.17; OR=3.49, 95% CI=1.03-11.80, respectively). Compared to Modern Orthodox women, non-Modern Orthodox women were more likely to consult with a rabbi or religious figure when considering genetic testing and other medical decisions. The focus group participants (N=31) confirmed the importance of rabbinic consultation in medical decision-making. Although stigma was not associated with genetic testing uptake in our survey data, it emerged as a prominent factor in decision-making among focus group participants due to its potential impact on marriageability and family.

Conclusions: We found that non-Modern Orthodox and unmarried women are less likely to seek BRCA genetic testing. Among non-Modern Orthodox women, rabbinic consultation was an important factor in genetic testing decision-making. By understanding the religious and cultural issues regarding genetic testing in the OJ community and by engaging faith-based leaders, we can develop culturally sensitive interventions designed to enhance knowledge and informed choice about BRCA genetic testing, which may facilitate the implementation of population-based genetic screening among Ashkenazi Jews.

Citation Format: Trivedi MS, Colbeth H, Yi H, Vanegas A, Starck R, Chung WK, Appelbaum PS, Kukafka R, Schechter I, Crew KD. Understanding factors associated with uptake of BRCA genetic testing among Orthodox Jewish women using a mixed-methods approach [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-06-19.

Association of the missense variant p.Arg203Trp in PACS1 as a cause of intellectual disability and seizures

Graphical abstract key: ADHD, attention deficit hyperactivity disorder; ASD, atrial septal defect; DD, developmental delay; EEG, electroencephalogram; Ht, height; ID, intellectual disability; OCD, obsessive-compulsive disorder; OFC, open fontanelle; PDA, patent ductus arteriosis; PFO, patent foramen ovale; VSD, ventricular septal defect; Wt, weight.

Further evidence that de novo missense and truncating variants in ZBTB18 cause intellectual disability with variable features

Identification of rare genetic variants in patients with intellectual disability (ID) has been greatly accelerated by advances in next generation sequencing technologies. However, due to small numbers of patients, the complete phenotypic spectrum associated with pathogenic variants in single genes is still emerging. Among these genes is ZBTB18 (ZNF238), which is deleted in patients with 1q43q44 microdeletions who typically present with ID, microcephaly, corpus callosum (CC) abnormalities, and seizures. Here we provide additional evidence for haploinsufficiency or dysfunction of the ZBTB18 gene as the cause of ID in five unrelated patients with variable syndromic features who underwent whole exome sequencing revealing separate de novo pathogenic or likely pathogenic variants in ZBTB18 (two missense alterations and three truncating alterations). The neuroimaging findings in our cohort (CC hypoplasia seen in 4/4 of our patients who underwent MRI) lend further support for ZBTB18 as a critical gene for CC abnormalities. A similar phenotype of microcephaly, CC agenesis, and cerebellar vermis hypoplasia has been reported in mice with central nervous system-specific knockout of Zbtb18. Our five patients, in addition to the previously described cases of de novo ZBTB18 variants, add to knowledge about the phenotypic spectrum associated with ZBTB18 haploinsufficiency/dysfunction.

De novo loss of function mutations in KIAA2022 are associated with epilepsy and neurodevelopmental delay in females

Intellectual disability (ID) affects about 3% of the population and has a male gender bias. Of at least 700 genes currently linked to ID, more than 100 have been identified on the X chromosome, including KIAA2022. KIAA2022 is located on Xq13.3 and is expressed in the developing brain. The protein product of KIAA2022, X‐linked Intellectual Disability Protein Related to Neurite Extension (XPN), is developmentally regulated and is involved in neuronal migration and cell adhesion. The clinical manifestations of loss‐of‐function KIAA2022 mutations have been described previously in 15 males, born from unaffected carrier mothers, but few females. Using whole‐exome sequencing, we identified a cohort of five unrelated female patients with de novo probably gene damaging variants in KIAA2022 and core phenotypic features of ID, developmental delay, epilepsy refractory to treatment, and impaired language, of similar severity as reported for male counterparts. This study supports KIAA2022 as a novel cause of X‐linked dominant ID, and broadens the phenotype for KIAA2022 mutations.

Characterizing cognitive control abilities in children with 16p11.2 deletion using adaptive 'video game' technology: a pilot study

Assessing cognitive abilities in children is challenging for two primary reasons: lack of testing engagement can lead to low testing sensitivity and inherent performance variability. Here we sought to explore whether an engaging, adaptive digital cognitive platform built to look and feel like a video game would reliably measure attention-based abilities in children with and without neurodevelopmental disabilities related to a known genetic condition, 16p11.2 deletion. We assessed 20 children with 16p11.2 deletion, a genetic variation implicated in attention deficit/hyperactivity disorder and autism, as well as 16 siblings without the deletion and 75 neurotypical age-matched children. Deletion carriers showed significantly slower response times and greater response variability when compared with all non-carriers; by comparison, traditional non-adaptive selective attention assessments were unable to discriminate group differences. This phenotypic characterization highlights the potential power of administering tools that integrate adaptive psychophysical mechanics into video-game-style mechanics to achieve robust, reliable measurements.

Abstract P2-09-23: Factors associated with BRCA genetic testing intention and uptake among Orthodox Jewish women

Background: Ashkenazi Jews have a 1 in 40 prevalence of carrying a BRCA1/2 mutation, mainly due to 3 founder mutations. Prior literature suggests that population-based genetic testing among Ashkenazi Jews is cost-effective and may detect over 50% more mutation carriers than family history-based screening. Orthodox Jewish women are an understudied population with unique social, cultural, and religious factors that may influence BRCA genetic testing. The aim of our study was to examine factors associated with BRCA genetic testing intention/uptake among the Orthodox Jewish community.

Methods: A one-time online survey was distributed to Orthodox Jewish women by 3 shuls from Washington Heights, NY (53% response rate) and through additional referrals. The questionnaire obtained information regarding demographics, breast cancer risk factors, genetic testing knowledge, decision self-efficacy, perceived breast cancer risk, breast cancer worry, and religious and cultural factors affecting medical decision-making. The Tyrer-Cuzick model was used to calculate lifetime breast cancer risk and accurate risk perception was defined as within +/-10% of actual lifetime risk. Descriptive statistics and multivariable logistic regression models were used to identify independent predictors of genetic testing intention/uptake.

Results: Among 342 evaluable participants, median age was 26 years (range, 19-77); 92% were Ashkenazi and 8% Ashkenazi/Sephardi; 98% had a college education, including 47% with post-graduate degrees. Despite being highly educated, only 54% of women had adequate genetic testing knowledge. Median lifetime breast cancer risk was 16% (range, 2.3-60.9) and only 44% had accurate breast cancer risk perceptions. Although 48% had a family history of breast cancer and 16% had a relative that tested positive for BRCA1/2 mutation, only 5% had undergone BRCA testing while 48% had the intention of undergoing genetic testing. Higher lifetime breast cancer risk, high decision self-efficacy regarding genetic testing, overestimation of breast cancer risk, and increased breast cancer worry were associated with genetic testing intention/uptake. The most important factors in the decision to have BRCA testing were to help prevent dying of cancer (55%), to help prevent getting cancer (54%), and effect on children (40%).

Multivariable analysis of factors associated with BRCA genetic testing intention/uptake OR95% CIp-valueDecision Self-Efficacy (range, 0 [not confident] - 4 [very confident])1.41.02-1.980.038Actual Lifetime Breast Cancer Risk (range, 0 - 100%)1.11.03-1.100.0005Accuracy in Breast Cancer Risk Perception   Accurate (referent)1.0--Underestimate1.20.50-2.850.691Overestimate2.61.45-4.610.001Breast Cancer Worry (range, 1 [none] - 7 [worry all of the time])1.51.18-1.980.001

Conclusions: By understanding the religious and cultural issues regarding genetic testing in the Orthodox Jewish community, we can develop targeted interventions designed to enhance decision self-efficacy and improve accuracy of breast cancer risk perceptions to decrease unnecessary worry. This may in turn increase informed decision-making about BRCA genetic testing and implementation of cancer prevention strategies among Ashkenazi Jews.

Citation Format: Trivedi MS, Tang EY, Kukufka R, Chung WK, David R, Respler L, Leifer S, Schechter I, Crew KD. Factors associated with BRCA genetic testing intention and uptake among Orthodox Jewish women. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-09-23.

Relationship between M100 Auditory Evoked Response and Auditory Radiation Microstructure in 16p11.2 Deletion and Duplication Carriers

BACKGROUND AND PURPOSE

Deletion and duplication of chromosome 16p11.2 (BP4-BP5) have been associated with developmental disorders such as autism spectrum disorders, and deletion subjects exhibit a large (20-ms) delay of the auditory evoked cortical response as measured by magnetoencephalography (M100 latency). The purpose of this study was to use a multimodal approach to test whether changes in white matter microstructure are associated with delayed M100 latency.

MATERIALS AND METHODS

Thirty pediatric deletion carriers, 9 duplication carriers, and 39 control children were studied with both magnetoencephalography and diffusion MR imaging. The M100 latency and auditory system DTI measures were compared between groups and tested for correlation.

RESULTS

In controls, white matter diffusivity significantly correlated with the speed of the M100 response. However, the relationship between structure and function appeared uncoupled in 16p11.2 copy number variation carriers. The alterations to auditory system white matter microstructure in the 16p11.2 deletion only partially accounted for the 20-ms M100 delay. Although both duplication and deletion groups exhibit abnormal white matter microstructure, only the deletion group has delayed M100 latency.

CONCLUSIONS

These results indicate that gene dosage impacts factors other than white matter microstructure, which modulate conduction velocity.

Laparoscopic internal fixation is a viable alternative option for continuous ambulatory peritoneal dialysis catheter insertion

Purpose

One of the major drawbacks of peritoneal dialysis (PD) is catheter migration and dysfunction. Preventing catheter migration is one of the main concerns. We compared laparoscopic internal fixation method with open surgical method for catheter migration rates.

Methods

From January 2008 to August 2009, PD catheters were inserted by laparoscopic fixation (LF) method in 22 patients and by open surgery (OS) in 32 patients. Clinical data were reviewed retrospectively. The frequency of migration, peritonitis, and other complications were compared. Catheter and patient survival rates were also compared.

Results

The mean age and sex ratio were not different between groups. Mean follow-up duration was 29.1 months in LF group and 26.1 months in OS group. More patients in LF group (27.3%) had history of laparotomy than in OS group (3.1%) (P = 0.01). The mean operation time was significantly longer in LF group (101.6 ± 30.4 minutes) than in OS group (72.4 ± 26.03 minutes) (P = 0.00). The cumulative incidence of catheter migration was 65.6% in OS group and 13.6% in LF group (P = 0.00). Migration-free catheter survival was higher in LF group (P = 0.001). There were no differences in complication rates between groups. Overall catheter survival was similar (P = 0.93). Patient survival rate at 2 years was not different (P = 0.13).

Conclusion

Laparoscopic internal fixation of continuous ambulatory peritoneal dialysis catheter significantly reduces migration rates without any addition of complications. Also, laparoscopic technique did not incur patient morbidity or mortality despite the requirement for general endotracheal anesthesia and longer operation time. Therefore, internal fixation can be afforded safely in patients with previous abdominal surgery as either a salvage or preventive measure in patients with repeated catheter migration.

Metastatic sarcomatoid carcinoma to liver and bone marrow in renal transplant recipient: due to exacerbation of quiescent renal cancer? A case report

Sarcomatoid carcinoma is a rare tumor with rapid growth and a poor prognosis. A 60-year-old man underwent kidney transplantation. Three months after transplantation, multiple tumors were found in the liver and bone, and the patient died several days later. Pathological examination of liver and bone marrow biopsies revealed metastatic sarcomatoid carcinoma. Pretransplantation, the patient's workup was positive only for mild thrombocytopenia and a complicated cyst with peripheral rim calcification (Bosniak IIF) in the right kidney. Retrospectively, we found the abdominal computed tomography film, which had been examined at another hospital 6 years previously. The calcified complicated cyst was a 3-cm enhancing solid mass in the right kidney, suggesting renal cell cancer. It is possible that the cancer developed from the calcified complicated cyst. In this case, immunosuppressants may have altered malignant cell proliferation, invasion, and the form of metastasis.

Six-Minute Walk Test demonstrates motor fatigue in spinal muscular atrophy

BACKGROUND

In spinal muscular atrophy (SMA), weakness, decreased endurance, and fatigue limit mobility. Scales have been developed to measure function across the wide spectrum of disease severity. However, these scales typically are observer dependent, and scores are based on sums across Likert-scaled items. The Six-Minute Walk Test (6MWT) is an objective, easily administered, and standardized evaluation of functional exercise capacity that has been proven reliable in other neurologic disorders and in children.

METHODS

To study the performance of the 6MWT in SMA, 18 ambulatory participants were evaluated in a cross-sectional study. Clinical measures were 6MWT, 10-m walk/run, Hammersmith Functional Motor Scale-Expanded (HFMSE), forced vital capacity, and handheld dynamometry. Associations between the 6MWT total distance and other outcomes were analyzed using Spearman correlation coefficients. A paired t test was used to compare the mean distance walked in the first and sixth minutes.

RESULTS

The 6MWT was associated with the HFMSE score (r = 0.83, p < 0.0001), 10-m walk/run (r = -0.87, p < 0.0001), and knee flexor strength (r = 0.62, p = 0.01). Gait velocity decreased during successive minutes in nearly all participants. The average first minute distance (57.5 m) was significantly more than the sixth minute distance (48 m) (p = 0.0003).

CONCLUSION

The Six-Minute Walk Test (6MWT) can be safely performed in ambulatory patients with spinal muscular atrophy (SMA), correlates with established outcome measures, and is sensitive to fatigue-related changes. The 6MWT is a promising candidate outcome measure for clinical trials in ambulatory subjects with SMA.

Expanding CEP290 mutational spectrum in ciliopathies

Ciliopathies are an expanding group of rare conditions characterized by multiorgan involvement, that are caused by mutations in genes encoding for proteins of the primary cilium or its apparatus. Among these genes, CEP290 bears an intriguing allelic spectrum, being commonly mutated in Joubert syndrome and related disorders (JSRD), Meckel syndrome (MKS), Senior-Loken syndrome and isolated Leber congenital amaurosis (LCA). Although these conditions are recessively inherited, in a subset of patients only one CEP290 mutation could be detected. To assess whether genomic rearrangements involving the CEP290 gene could represent a possible mutational mechanism in these cases, exon dosage analysis on genomic DNA was performed in two groups of CEP290 heterozygous patients, including five JSRD/MKS cases and four LCA, respectively. In one JSRD patient, we identified a large heterozygous deletion encompassing CEP290 C-terminus that resulted in marked reduction of mRNA expression. No copy number alterations were identified in the remaining probands. The present work expands the CEP290 genotypic spectrum to include multiexon deletions. Although this mechanism does not appear to be frequent, screening for genomic rearrangements should be considered in patients in whom a single CEP290 mutated allele was identified.

Validity of interferon-γ-release assays for the diagnosis of latent tuberculosis in haemodialysis patients

Haemodialysis patients are at higher risk of developing active tuberculosis (TB) infection. However, tuberculin skin tests (TST) have limitations and the diagnostic usefulness of interferon-γ-release assays (IGRAs) remains unclear in immunocompromised hosts including haemodialysis patients. Haemodialysis patients were enrolled from a dialysis centre in Korea, an intermediate TB-burden country with a high bacille Calmette-Guérin (BCG) vaccination rate. The QuantiFERON-Gold TB In tube test (QFT) and the T-SPOT TB test (TSPOT) were performed, along with the TST. We stratified patients to low- and high-risk groups, according to the risk factors for latent TB. Association between each of the three diagnostic tests and the risk of latent TB was analysed. One hundred and sixty-seven patients were enrolled. The positive rates for the TST, the QFT and TSPOT were 23.5, 45.9 and 60.4%, respectively. Previous BCG vaccination increased the TST-positive rate in the low-risk group (OR 4.438), whereas it affected neither QFT nor TSPOT. The positive QFT rates were 41.2 and 62.5% in the low- and high-risk groups, respectively. The QFT was associated with the high-risk group (OR 2.578), whereas the TST was not. The positive TSPOT rates were 58.9 and 65.7% in the low- and high-risk groups, respectively. The frequency of indeterminate results was higher for the QFT (12.6%) compared with the TSPOT (4.8%). In conclusion, the IGRAs can be useful for the diagnosis of latent TB infection in haemodialysis patients.

Photocatalytic oxidation of polycyclic aromatic hydrocarbons: intermediates identification and toxicity testing

Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic pollutants and their low water solubility limits their degradation in aqueous solution. The presence of water-miscible solvent such as acetone can increase the water solubility of PAHs, however acetone will also affect the degradation of PAH. In this study the effects of acetone on the photocatalytic degradation efficiency and pathways of 5 selected PAHs, namely naphthalene (2 rings), acenaphthylene (3 rings), phenanthrene (3 rings), anthracene (3 rings) and benzo[a]anthracene (4 rings) were investigated. The Microtox toxicity test was used to determine whether the PCO system can completely detoxify the parental PAHs and its intermediates. The addition of 16% acetone can greatly alter the degradation pathway of naphthalene and anthracene. Based on intermediates identified from degradation of the 5 PAHs, the location of parental PAHs attacked by reactive free radicals can be correlated with the localization energies of different positions of the compound. For toxicity analysis, irradiation by UV light was found to induce acute toxicity by generating intermediates/degradation products from PAHs and possibly acetone. Lastly, all PAHs (10 mg l(-1)) can be completely detoxified by titanium dioxide (100 mg l(-1)) within 24h under UVA irradiation (3.9 mW cm(-2)).

Association of angiotensin II type 2 receptor gene A1818T polymorphism with progression of immunoglobulin A nephropathy in Korean patients

We determined the relationship between the progression of immunoglobulin A nephropathy (IgAN) and the A1818T polymorphism in intron 2 of Angiotensin II type 2 receptor (AT2R) gene, which might play protective roles in the pathogenesis of IgAN. Patients with biopsy-proven IgAN were recruited from the registry of the Progressive REnal disease and Medical Informatics and gEnomics Research (PREMIER) which was sponsored by the Korean Society of Nephrology. A1818T polymorphism of AT2R gene was analyzed with PCR-RFLP method and the association with the progression of IgAN, which was defined as over 50% increase in baseline serum creatinine level, was analyzed with survival analysis. Among the 480 patients followed for more than 10 months, the group without T allele had significantly higher rates of progression of IgAN than the group with T allele (11.4% vs. 3.9%, p=0.024), although there were no significant differences in the baseline variables such as initial serum creatinine level, the degree of proteinuria, and blood pressure. In the Cox's proportional hazard model, the hazard ratio of disease progression in the patients with T allele was 0.221 (95% confidence interval for Exp(B): 0.052-0.940, p=0.041) compared to that of without T allele. In conclusion, A1818T polymorphism of AT2R gene was associated with the progression of IgAN.

A novel mutation in NDUFS4 causes Leigh syndrome in an Ashkenazi Jewish family

Leigh syndrome is a neurodegenerative disorder of infancy or childhood generally due to mutations in nuclear or mitochondrial genes involved in mitochondrial energy metabolism. We performed linkage analysis in an Ashkenazi Jewish (AJ) family without consanguinity with three affected children. Linkage to microsatellite markers D5S1969 and D5S407 led to evaluation of the complex I gene NDUFS4, in which we identified a novel homozygous c.462delA mutation that disrupts the reading frame. The resulting protein lacks a cAMP-dependent protein kinase phosphorylation site required for activation of mitochondrial respiratory chain complex I. In a random sample of 5000 healthy AJ individuals, the carrier frequency of the NDUFS4 mutation c.462delA was 1 in 1000, suggesting that it should be considered in all AJ patients with Leigh syndrome.

Pulmonary artery hypertension in a child with MELAS due to a point mutation of the mitochondrial tRNA((Leu)) gene (m.3243A>G)

Although linked with cardiac dysfunction, the association of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) and pulmonary artery hypertension (PAH) has not been previously described. PAH and right ventricular heart failure were identified by echocardiography in a 3-year-old boy with a history of hypotonia, microcephaly and developmental delay. He initially presented with a 10-day history of dyspnoea, dependent oedema and reduced oral intake. Lactic acidosis was noted on serial arterial blood sampling and cerebrospinal fluid. Muscle biopsy demonstrated cytochrome-c oxidase-positive 'ragged-red' fibres consistent with MELAS; subsequent analyses revealed the m.3243A>G point mutation most commonly associated with MELAS. The mutation was heteroplasmic, representing 92% of the total mtDNA from a lung sample. Nitric oxide and epoprostenol were administered without significant clinical or echocardiographic improvement of his PAH. A 'mitochondrial cocktail' including biotin, riboflavin, carnitine and coenzyme Q10 also was provided. Five months after presentation, he developed seizures; MRI imaging of his brain demonstrated multiple focal lesions. His clinical status worsened with increasing cardiopulmonary failure. He died two months later. Although therapy for both MELAS and PAH remains limited, recent investigations suggest a beneficial role for l-arginine in both conditions, implying a possible common pathophysiology. Mitochondrial diseases such as MELAS should be considered in cases of idiopathic PAH, particularly when associated with multisystem involvement including short stature, hearing loss, renal dysfunction, retinopathy, diabetes mellitus, migraines, seizures, ophthalmoplegia, fatigability and weakness.

Adsorption of copper ion on magnetite-immobilised chitin

The adsorption of Cu2+ from aqueous solution by magnetite-immobilised chitin (MC) was studied in batch mode. Two conventional adsorbents, cation exchange resin (CER) and activated carbon (AC) were used for the comparison. The physicochemical parameters including pH, concentration of adsorbent, temperature and initial Cu2+ concentration were optimised. Under the optimised conditions, the removal efficiencies of Cu2+ for MC, CER and AC were 91.67, 93.36 and 89.16%, respectively. In addition, the removal capacities of Cu2+ for MC, CER and AC were 56.71, 74.84 and 6.55 mg/g, respectively. The adsorption isotherm studies indicated that the adsorptive behaviour of Cu2+ on three adsorbents could be well described by the Langmuir model. The maximum adsorption capacities (qmax) for MC, CER and AC were 53.19, 89.29 and 5.82 mg/g, respectively. The applicability of the kinetic model has been investigated for MC. Experimental results indicated that a pseudo-second-order reaction model provided the best description of the data with a correlation coefficient 0.999 for different initial Cu2+ concentrations. The rate constants were also determined. Various thermodynamic parameters such as standard free energy (DeltaG 0), enthalpy (DeltaH 0) and entropy (DeltaS 0) were calculated for predicting the adsorption nature of MC. The results indicated that this system was a spontaneous and endothermic process.

Photocatalytic degradation of di(2-ethylhexyl)phthalate adsorbed by chitin A

Di(2-ethylhexyl)phthalate (DEHP) is a ubiquitous environmental contaminant due to its extensive use as a plasticiser and its persistence. Currently, there is no cost-effective treatment method for its removal from industrial wastewater. In a previous study, DEHP was effectively adsorbed from aqueous solution by biosorption onto chitinous materials. Biosorption can pre-concentrate DEHP from the aqueous phase for further treatment. As biosorption cannot degrade DEHP, in this study the degradation (and detoxification) of DEHP adsorbed onto chitinous material by photocatalytic oxidation (PCO) is attempted. PCO relies on hydroxyl radical (.OH), which is a strong oxidising agent, for the oxidative degradation of pollutants. It is a non-selective process which can degrade DEHP adsorbed onto chitinous material. The first part of this study is the optimisation of the degradation of adsorbed DEHP by PCO. Adsorption was carried out in the physicochemical conditions optimised in the previous study, with 500 mg/L chitin A and 40 mg/L DEHP at initial pH 2, 22+/-2 degrees C and 150 rpm agitation for 5 min. After optimisation of PCO, a 61% removal efficiency of 10 mg/L of DEHP was achieved within 45 min under 0.65 mW/cm2 of UV-A with 100 mg/L TiO2, and 10 mM of H2O2 at initial pH 12. The optimisation study showed that UV-A and TiO(2) are essential for the degradation of DEHP by PCO. The degradation intermediates/products were identified by GC-MS analysis. GC-MS results showed that the di(2-ethylhexyl) side chain was first degraded, producing phthalates with shorter side chains. Further reaction produced phathalic anhydride and aliphatic compounds such as alkanol and ester. The toxicities of parental and degradation intermediates in the solution phase and on chitinous materials were followed by the Microtox test. Results indicated that toxicity can be removed after 4 h treatment by PCO. Thus the decontamination of DEHP by integrating biosorption and PCO is feasible.

Association of K121Q polymorphism in ENPP1 (PC-1) with BMI in Caucasian and African-American adults

OBJECTIVE

To test for association of the ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) K121Q polymorphism with body mass index (BMI) and diabetes in a large sample of Caucasians and African-Americans by selectively genotyping individuals at the extremes of the phenotypic distribution.

SUBJECTS

Subsets comprising the extremes of the BMI distribution (10th-20th and above the 90th BMI percentile for Caucasians and between the 10th-30th and above the 80th percentile for African-Americans) from a group of 10,260 Caucasian and 2268 African-American adults participating in New York Cancer Project were studied.

METHODS

Subjects were genotyped for the ENPP1 K121Q polymorphism by pyrosequencing and tested for association with BMI and diabetes by regression analysis.

RESULTS

Regression analysis with BMI as the dependent variable demonstrated a significant association (P = 0.02) of genotype at K121Q with BMI, with no significant race-by-genotype interaction (P = 0.30). Compared with Q/Q or Q/K individuals, the K/K individuals had a BMI approximately 1.3 kg/m2 higher, without effects of age, gender or race. By logistic regression analysis, the K121Q alleles had no significant effect on diabetes status (P = 0.37) in obese subjects.

CONCLUSION

In both Caucasians and African-Americans, the K121 polymorphism in ENPP1 was associated with increased BMI, but not with diabetes.

Effects of radiation therapy on the lung: radiologic appearances and differential diagnosis

Radiation-induced lung disease (RILD) due to radiation therapy is common. Radiologic manifestations are usually confined to the lung tissue within the radiation port and are dependent on the interval after completion of treatment. In the acute phase, RILD typically manifests as ground-glass opacity or attenuation or as consolidation; in the late phase, it typically manifests as traction bronchiectasis, volume loss, and scarring. However, the use of oblique beam angles and the development of newer irradiation techniques such as three-dimensional conformal radiation therapy can result in an unusual distribution of these findings. Awareness of the atypical manifestations of RILD can be useful in preventing confusion with infection, recurrent malignancy, lymphangitic carcinomatosis, and radiation-induced tumors. In addition, knowledge of radiologic findings that are outside the expected pattern for RILD can be useful in diagnosis of infection or recurrent malignancy. Such findings include the late appearance or enlargement of a pleural effusion; development of consolidation, a mass, or cavitation; and occlusion of bronchi within an area of radiation-induced fibrosis. A comprehensive understanding of the full spectrum of these manifestations is important to facilitate diagnosis and management in cancer patients treated with radiation therapy.

Down-regulation of MHC class I expression in human neuronal stem cells using viral stealth mechanism

Due to their unique capacity for self-renewal in addition to their ability to differentiate into cells of all neuronal lineages, neuronal stem cells (NSCs) are promising candidates for cell replacement therapy in neuronal injury and neurodegenerative diseases. However, there are few studies on immune rejection, which is one of the main problems facing successful stem cell therapy. In order to determine if human NSC might be rejected after transplantation the MHC expression level was examined in the HB1.F3 cell line, which has previously been shown to exhibit NSC properties. The results showed low expression levels of the MHC class I molecules on the surfaces of these cells. A dramatic increase in the MHC class I expression level was observed when the cells were treated with IFN-gamma, TNF-alpha, and IL-1beta, alone or in combination. The maximum induction of MHC class I protein expression was observed at above 20ng/ml IFN-gamma 48h after the treatment. The apparent additive effects of TNF-alpha and IL-1beta in combination on the maximum induction of MHC class I expression exerted by IFN-gamma treatment were not observed. The MHC class I levels elevated by IFN-gamma were sustained for 72h after withdrawing the IFN-gamma. Therefore, this study introduced human cytomegalovirus (hCMV) US genes, which are known to be able to reduce the MHC class I expression level on the cell surface after infection, into HB1.F3 cells. The cells transfected with the hCMV US2, US3, US6 or US11 genes showed 20-50% reduction in the MHC class I expression level compared with the mock-transfected cells. These results suggest that NSC expresses high levels of the MHC class I proteins, and unless they are modified, might be rejected upon transplantation. In addition, the various viral stealth mechanisms can be exploited for stem cell transplantation.

Mini-incision total hip replacement--surgical technique and early results

PURPOSE

To compare the results of mini-incision total hip replacement (MITHR) to the standard posterior approach and evaluate the advantages and disadvantages of MITHR.

METHODS

60 patients with osteoarthritis of the hip underwent total hip replacement utilising a mini-incision technique. They were compared to a matched cohort of patients who received the standard posterior approach. The average follow-up period was 14 months. The patients were compared with respect to the length of the incision, surgical time, intra-operative blood loss, narcotic requirements, length of hospital stay, requirement for walking aids, Harris hip score, and complications.

RESULTS

The length of the skin incision for MITHR, at an average of 9.2 cm, was half that of the standard approach. Statistically significant differences were found between the 2 groups in terms of intra-operative blood loss, length of hospital stay, and use of walking aids, all in favour of MITHR. There were no differences between the two approaches with regard to operating time, narcotic requirements, or Harris hip score. There were no cases of component malpositioning or major complications in the MITHR group.

CONCLUSION

Uncemented total hip replacement can be effectively performed through a smaller incision utilising MITHR without increased risk of complications. Significant benefits include less intra-operative blood loss, shorter hospitalisation, and cosmesis.

In vitro assessment of proximal polyethylene contact surface areas and stresses in mobile bearing knees

Wear of the polyethylene (PE) insert in total knee arthroplasty remains a significant problem. The generation of biologically active wear particles may ultimately affect implant longevity through osteolysis or premature/catastrophic PE failure. The rate and pattern of wear is influenced by many factors, including component geometry and individual loading conditions, which determine the contact surface area and kinematics of the reconstructed knee. Contact areas and stresses at the proximal femoral-PE insert interface and distal PE-tibial interface contact surface areas were measured in nine mobile bearing total knee designs at 0, 30, 60, 90 and 110 degrees of flexion at 3600 N (5 x body weight) using a standardized test method. Proximal and, to a lesser degree, distal interface contact area footprints decreased significantly with increasing flexion angle based on the conformity of the designs, resulting in a corresponding increase in the mean and peak stresses.

Surface roughness of the proximal and distal bearing surface of mobile bearing total knee prostheses

Proximal and distal articulations surface roughness measurements were done on 8 mobile bearing knee designs immediately after removal from sterile packaging. Roughness parameters Ra and Rp based on ISO 97, representing mean deviation from the smooth surface line and mean peak to smooth surface line, were recorded using a contact surface profilometer at 10 random sites in the anteroposterior and mediolateral direction on the femoral and tibial metal components and the proximal and distal surface of the ultra-high molecular weight polyethylene (PE) inserts. No differences were found for surface roughness values for the metal components. Surface roughness values were greater for the distal PE bearing surfaces compared with the proximal PE bearing surfaces for each design tested. The roughness values for the PE inserts showed a directional dependence. Complex kinematics of mobile bearing knees coupled with this rougher distal interface could influence the rate of generation of wear particles and total volume of particles produced especially in the early postoperative period.

A meta-analytic investigation of linkage and association of common leptin receptor (LEPR) polymorphisms with body mass index and waist circumference

METHODS

We analyzed data pooled from nine studies on the human leptin receptor (LEPR) gene for the association of three alleles (K109R, Q223R and K656N) of LEPR with body mass index (BMI; kg/m(2)) and waist circumference (WC). A total of 3263 related and unrelated subjects from diverse ethnic backgrounds including African-American, Caucasian, Danish, Finnish, French Canadian and Nigerian were studied. We tested effects of individual alleles, joint effects of alleles at multiple loci, epistatic effects among alleles at different loci, effect modification by age, sex, diabetes and ethnicity, and pleiotropic genotype effects on BMI and WC.

RESULTS

We found that none of the effects were significant at the 0.05 level. Heterogeneity tests showed that the variations of the non-significant effects are within the range of sampling variation.

CONCLUSIONS

We conclude that, although certain genotypic effects could be population-specific, there was no statistically compelling evidence that any of the three LEPR alleles is associated with BMI or WC in the overall population.