SLC6A3 coding variant Ala559Val found in two autism probands alters dopamine transporter function and trafficking

Emerging evidence associates dysfunction in the dopamine (DA) transporter (DAT) with the pathophysiology of autism spectrum disorder (ASD). The human DAT (hDAT; SLC6A3) rare variant with an Ala to Val substitution at amino acid 559 (hDAT A559V) was previously reported in individuals with bipolar disorder or attention-deficit hyperactivity disorder (ADHD). We have demonstrated that this variant is hyper-phosphorylated at the amino (N)-terminal serine (Ser) residues and promotes an anomalous DA efflux phenotype. Here, we report the novel identification of hDAT A559V in two unrelated ASD subjects and provide the first mechanistic description of its impaired trafficking phenotype. DAT surface expression is dynamically regulated by DAT substrates including the psychostimulant amphetamine (AMPH), which causes hDAT trafficking away from the plasma membrane. The integrity of DAT trafficking directly impacts DA transport capacity and therefore dopaminergic neurotransmission. Here, we show that hDAT A559V is resistant to AMPH-induced cell surface redistribution. This unique trafficking phenotype is conferred by altered protein kinase C β (PKCβ) activity. Cells expressing hDAT A559V exhibit constitutively elevated PKCβ activity, inhibition of which restores the AMPH-induced hDAT A559V membrane redistribution. Mechanistically, we link the inability of hDAT A559V to traffic in response to AMPH to the phosphorylation of the five most distal DAT N-terminal Ser. Mutation of these N-terminal Ser to Ala restores AMPH-induced trafficking. Furthermore, hDAT A559V has a diminished ability to transport AMPH, and therefore lacks AMPH-induced DA efflux. Pharmacological inhibition of PKCβ or Ser to Ala substitution in the hDAT A559V background restores AMPH-induced DA efflux while promoting intracellular AMPH accumulation. Although hDAT A559V is a rare variant, it has been found in multiple probands with neuropsychiatric disorders associated with imbalances in DA neurotransmission, including ADHD, bipolar disorder, and now ASD. These findings provide valuable insight into a new cellular phenotype (altered hDAT trafficking) supporting dysregulated DA function in these disorders. They also provide a novel potential target (PKCβ) for therapeutic interventions in individuals with ASD.

Lubricin is Required for the Structural Integrity and Post-natal Maintenance of TMJ

The Proteoglycan 4 (Prg4) product lubricin plays essential roles in boundary lubrication and movement in limb synovial joints, but its roles in temporomandibular joint (TMJ) are unclear. Thus, we characterized the TMJ phenotype in wild-type and Prg4(-/-) mouse littermates over age. As early as 2 weeks of age, mutant mice exhibited hyperplasia in the glenoid fossa articular cartilage, articular disc, and synovial membrane. By 1 month of age, there were fewer condylar superficial tenascin-C/Col1-positive cells and more numerous apoptotic condylar apical cells, while chondroprogenitors displayed higher mitotic activity, and Sox9-, Col2-, and ColX-expressing chondrocyte zones were significantly expanded. Mutant subchondral bone contained numerous Catepsin K-expressing osteoclasts at the chondro-osseous junction, increased invasive marrow cavities, and suboptimal subchondral bone. Mutant glenoid fossa, disc, synovial cells, and condyles displayed higher Hyaluronan synthase 2 expression. Mutant discs also lost their characteristic concave shape, exhibited ectopic chondrocyte differentiation, and occasionally adhered to condylar surfaces. A fibrinoid substance of unclear origin often covered the condylar surface. By 6 months of age, mutant condyles displayed osteoarthritic degradation with apical/mid-zone separation. In sum, lubricin exerts multiple essential direct and indirect roles to preserve TMJ structural and cellular integrity over post-natal life.

Abstract P1-13-16: Women commencing with anastrozole, letrozole or tamoxifen: The impact of comorbidity and demographics on initial choice

Background: Australian clinical guidelines recommend post-surgical endocrine therapy for all women with early, hormone-dependent breast cancer. Guidelines specify tamoxifen as first-line therapy for pre-menopausal women, and either tamoxifen or an aromatase inhibitor for post-menopausal women depending on their risk of recurrence which is based on tumour size and other prognostic indicators. Tamoxifen and the aromatase inhibitors have different side effect profiles and therefore comorbidity may also influence choice of therapy. We examined comorbidities, and the clinical and demographic characteristics of women initiated on different endocrine therapies for breast cancer in Australian practice.

Method: We identified the first dispensing of tamoxifen, anastrozole or letrozole for women diagnosed with invasive breast cancer in the 45 and Up Study between January 2003 and December 2009 (n = 1383). Unit-level pharmacy and medical service claims, hospital separations, and Cancer Registry records were linked to self-reported data to determine menopause status at diagnosis, tumour size, age, change in subsidy restrictions, and specified comorbidities which may affect choice of therapy (i.e. arthritis, endometrial cancer, osteoporosis, thromboembolism). Chi-square tests and multivariate generalised linear models were used to compare the characteristics of post-menopausal women initiated on different therapies.

Results: The majority of pre-menopausal women commenced therapy with tamoxifen (93%). Tamoxifen was the predominant therapy for post-menopausal women with tumours ≤1cm (54%), and anastrozole most common for those with larger tumours (49%). Post-menopausal women with osteoporosis were less likely to commence an aromatase inhibitor compared with tamoxifen (anastrozole RR = 0.7, 95%CI = 0.5-0.9, P = 0.019; letrozole RR = 0.6, 95%CI = 0.3-0.9, P = 0.033) and those with arthritis were 1.6-times more likely to commence with letrozole than anastrozole (95%CI = 1.6-2.3, P = 0.004). Tamoxifen was more likely to be initiated in women with large tumours who also had comorbid arthritis or were aged ≥75 years. Changes in subsidy restrictions were associated with significant increases in the proportion of post-menopausal women commencing an aromatase inhibitor rather than tamoxifen (anastrozole RR = 7.0; letrozole RR = 18.5).

Conclusions: The findings show clinical guidelines regarding endocrine therapies are being followed in Australian practice, particularly in relation to menopause status and tumour size as a recurrence risk factor. The findings also indicate there is interplay of comorbidity and choice of therapy for older women and those with arthritis or osteoporosis.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-13-16.

Abstract P5-14-12: Cosmetic outcome is better after intraoperative radiotherapy compared with external beam radiotherapy: An objective assessment of patients from a randomized controlled trial

The randomised controlled TARGeted Intraoperative radioTherapy (TARGIT) Trial has demonstrated non-inferiority between the novel technique of TARGIT (intra-operative radiotherapy with Intrabeam ®) and conventional whole-breast external beam radiotherapy (EBRT) in women with early breast cancer, in terms of the primary outcome measure of risk of local relapse within the treated breast. As there are very low recurrence rates, cosmesis becomes an increasingly important outcome of breast conserving treatment with both surgery and radiotherapy. This study was performed to determine if the single high dose of TARGIT compared with EBRT leads to impaired cosmesis.

A validated, objective assessment software tool for evaluation of cosmetic outcome was used. Frontal digital photographs were taken at baseline (before radiotherapy) and annually thereafter for up to five years. The photographs were analysed by BCCT.core which produces a composite score based on symmetry, colour and scar.

A total of 342 patients were assessed, all over 50 years old with a median age at baseline of 64 years (IQR 59 to 68). The BCCT.core scores were dichotomised into Excellent and Good (EG), and Fair and Poor (FP). There were statistically significant increases in the odds of having an outcome of EG for patients in the TARGIT group compared with the EBRT group at year 1 (OR = 2.07, 95%CI 1.12 to 3.85, p = 0.021) and year 2 (OR = 2.11, 95%CI 1.0 to 4.45, p = 0.05).

This objective assessment of aesthetic outcome in patients from a randomised setting demonstrates that those treated with targeted intraoperative radiotherapy have a superior cosmetic result compared with those patients who received conventional whole-breast external beam radiotherapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-14-12.

Abstract S3-01: Breast cancer prevention using anastrozole in postmenopausal women at high risk

Background: Third generation aromatase inhibitors are the most effective endocrine treatment for hormone receptor positive breast cancer in postmenopausal women. Here, we assess the efficacy of anastrozole in postmenopausal women who do not have breast cancer, but are at high risk of developing the disease.

Methods: A multi-centre randomised placebo-controlled trial of 1mg/day oral anastrozole vs. matching placebo for five years was conducted in 3864 postmenopausal women at increased risk of breast cancer. The primary endpoint was the incidence of breast cancer (including ductal carcinoma in-situ (DCIS) and differences were assessed by the proportional hazards model. Detailed information on adverse events was collected.

Results: After a median follow up of 5.03 years, 125 breast cancers were recorded. A 53% reduction (95% CI (32-68%), P<0.0001) was seen in the anastrozole arm. Significant reductions were seen for all invasive (50%), oestrogen receptor positive invasive (58%) and in situ tumours (70%). Fractures were non-significantly higher (8.5% vs. 7.7%, P = 0.3) and musculoskeletal events were significantly higher in the anastrozole arm (1226 vs. 1124, RR = 1.10 (1.05-1.16)) but were very common in both arms (63.9% vs. 57.8%). Vasomotor symptoms were also increased with anastrozole (RR = 1.15 (1.08-1.22)). Cancers at other sites were significantly decreased (40 vs. 70, RR = 0.58 (0.39-0.85)). Deaths from breast cancer and other causes were similar in both arms.

Conclusions: Anastrozole is an effective agent for reducing breast cancer incidence in postmenopausal women at high risk. Anastrozole was well tolerated and side effects associated with oestrogen deprivation were only slightly higher than for placebo.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S3-01.

Lung clearance index and high-resolution computed tomography scores in primary ciliary dyskinesia

RATIONALE

Lung clearance index (LCI) is a more sensitive measure of lung function than spirometry in cystic fibrosis (CF) and correlates well with abnormalities in high-resolution computed tomography (HRCT) scanning. We hypothesized LCI would be equally sensitive to lung disease in primary ciliary dyskinesia (PCD).

OBJECTIVES

To test the relationships between LCI, spirometry, and HRCT in PCD and to compare them to the established relationships in CF.

METHODS

Cross-sectional study of 127 patients with CF and 33 patients with PCD, all of whom had spirometry and LCI, of which a subset of 21 of each had HRCT performed. HRCT was scored for individual features and these features compared with physiological parameters.

MEASUREMENTS AND MAIN RESULTS

Unlike in CF, and contrary to our hypothesis, there was no correlation between spirometry and LCI in PCD and no correlation between HRCT features and LCI or spirometry in PCD.

CONCLUSIONS

We show for the first time that HRCT, spirometry, and LCI have different relationships in different airway diseases and that LCI does not appear to be a sensitive test of airway disease in advanced PCD. We hypothesize that this results from dissimilarities between the components of large and small airway disease in CF and PCD. These differences may in part lead to the different prognosis in these two neutrophilic airway diseases.

Impact of an intervention nutrition program during prenatal on the weight of newborns from teenage mothers

INTRODUCTION

The nutritional care for teenage mothers had been studied as a factor that influences the course of pregnancy and neonatal outcomes, especially in birth weight.

OBJECTIVE

Evaluate the effect of a prenatal intervention nutrition program, with early start of the nutritional care and individualized attendance on teenage mother newborns' weight.

METHODS

Not randomized study of intervention performed with 746 teenage mothers (14 to 19 years old), subdivided in historic control group (GI; n= 542) and intervention group (GII; n= 204). The dependent variable was the low birth weight (LBW). The independent variables assessed were: sociodemographic (mother age, skin color, instruction level and sanitation conditions), anthropometric (mother's height, pre-gestational nutritional study and adequacy of gestational weight gain), obstetric (gestational age in first prenatal consultation, number of pregnancies, childbirths and abortions, interdelivery and inter-gestational intervals), prenatal attendance (number of prenatal and nutritional attendance consultations) and conditions of the newborn (birth weight and duration of the pregnancy). Data were analyzed by Poisson regression with robust variance.

RESULTS

The average of maternal age at delivery was 17,5 years old (standard deviation 1,59). The percentage of LBW considerably reduced from 11,3% in GI to 2,9% in GII (p < 0,001). We observed in the multivariate model that the teenage mothers who have not received the intervention presented 3,5 more prevalence (GI, RP adjusted 3,5; IC95% 1,49-8,44) to give birth to a low weight newborn.

CONCLUSION

The participation of the teenage mother in the prenatal nutrition care program proposed here contributed to the reduction of the low weight of newborns.

The association between different night shiftwork factors and breast cancer: a case-control study

BACKGROUND

Research on the possible association between shiftwork and breast cancer is complicated because there are many different shiftwork factors, which might be involved including: light at night, phase shift, sleep disruption and changes in lifestyle factors while on shiftwork (diet, physical activity, alcohol intake and low sun exposure).

METHODS

We conducted a population-based case-control study in Western Australia from 2009 to 2011 with 1205 incident breast cancer cases and 1789 frequency age-matched controls. A self-administered questionnaire was used to collect demographic, reproductive, and lifestyle factors and lifetime occupational history and a telephone interview was used to obtain further details about the shiftwork factors listed above.

RESULTS

A small increase in risk was suggested for those ever doing the graveyard shift (work between midnight and 0500 hours) and breast cancer (odds ratio (OR)=1.16, 95% confidence interval (CI)=0.97-1.39). For phase shift, we found a 22% increase in breast cancer risk (OR=1.22, 95% CI=1.01-1.47) with a statistically significant dose-response relationship (P=0.04). For the other shiftwork factors, risks were marginally elevated and not statistically significant.

CONCLUSION

We found some evidence that some of the factors involved in shiftwork may be associated with breast cancer but the ORs were low and there were inconsistencies in duration and dose-response relationships.

Factors influencing stethoscope cleanliness among clinical medical students

This study aims to identify current stethoscope hygiene habits and attitudes in a UK medical school setting. Students completed a questionnaire using Likert-scale questions and free-text answers. A total of 308 questionnaires were completed from a potential 750 students (41%); 22.4% of respondents had never cleaned their stethoscope and only 3.9% cleaned their stethoscope after every patient. Significant correlations were identified between cleaning frequency and: others acting as role models (P = 0.001), students having confidence in how to clean stethoscopes (P = 0.001), and students thinking cleaning was important (P = 0.01), thereby highlighting inadequate education and role models as potential problems.

External validity of randomized controlled trials of glycaemic control and vascular disease: how representative are participants?

AIMS

To describe the proportion of people with Type 2 diabetes living in Scotland who meet eligibility criteria for inclusion in several large randomized controlled trials of glycaemic control to inform physicians and guideline developers about the generalizibility of trial results.

METHODS

A literature review was performed to identify large trials assessing the impact of glycaemic control on risk of macrovascular disease. Inclusion and exclusion criteria from each trial were applied to data on the population of people with a diagnosis of Type 2 diabetes living in Scotland in 2008 (n = 180,590) in a population-based cross-sectional study and the number and proportion of people eligible for each trial was determined.

RESULTS

Seven trials were identified. The proportion of people with Type 2 diabetes who met the eligibility criteria for the trials ranged from 3.5 to 50.7%. Trial participants were younger at age of diagnosis of diabetes and at time of trial recruitment than in the Scottish study population. The application of upper age criteria excluded the largest proportion of patients, with up to 39% of people with Type 2 diabetes ineligible for a trial with the most stringent criteria based on age alone.

CONCLUSIONS

We found that many of the large trials of glycaemic control among people with Type 2 diabetes have limited external validity when applied to a population-based cohort of people with Type 2 diabetes. In particular, the age distribution of trial participants often does not reflect that of people with Type 2 diabetes in a contemporary British population.

Changes in physiological, functional and structural markers of cystic fibrosis lung disease with treatment of a pulmonary exacerbation

BACKGROUND

Clinical trials in cystic fibrosis (CF) have been hindered by the paucity of well characterised and clinically relevant outcome measures.

AIM

To evaluate a range of conventional and novel biomarkers of CF lung disease in a multicentre setting as a contributing study in selecting outcome assays for a clinical trial of CFTR gene therapy.

METHODS

A multicentre observational study of adult and paediatric patients with CF (>10 years) treated for a physician-defined exacerbation of CF pulmonary symptoms. Measurements were performed at commencement and immediately after a course of intravenous antibiotics. Disease activity was assessed using 46 assays across five key domains: symptoms, lung physiology, structural changes on CT, pulmonary and systemic inflammatory markers.

RESULTS

Statistically significant improvements were seen in forced expiratory volume in 1 s (p<0.001, n=32), lung clearance index (p<0.01, n=32), symptoms (p<0.0001, n=37), CT scores for airway wall thickness (p<0.01, n=31), air trapping (p<0.01, n=30) and large mucus plugs (p=0.0001, n=31), serum C-reactive protein (p<0.0001, n=34), serum interleukin-6 (p<0.0001, n=33) and serum calprotectin (p<0.0001, n=31).

DISCUSSION

We identify the key biomarkers of inflammation, imaging and physiology that alter alongside symptomatic improvement following treatment of an acute CF exacerbation. These data, in parallel with our study of biomarkers in patients with stable CF, provide important guidance in choosing optimal biomarkers for novel therapies. Further, they highlight that such acute therapy predominantly improves large airway parameters and systemic inflammation, but has less effect on airway inflammation.

Impact of glucose and acetate on the characteristics of the platelet storage lesion in platelets suspended in additive solutions with minimal plasma

BACKGROUND AND OBJECTIVES

Glucose and acetate have been proposed to be required elements in platelet storage media. This study investigated the role of these compounds on the varied elements that comprise the platelet storage lesion.

MATERIALS AND METHODS

For each replicate, four pooled and split ABO group-specific buffy coat-derived platelet concentrates were suspended in an in-house additive solution with minimal plasma and varying final concentrations of acetate or glucose. Units were sampled on days 2, 3, 6, 8 and 10 and tested for markers of platelet morphology, activation, function, metabolism and indicators of cell death.

RESULTS

The absence of glucose was associated with a decrease in ATP, falling to a mean of 1·1 ± 0·1 μmol/10(11) plts in units with no added glucose compared with 4·2 ± 0·6 μmol/10(11) plts (P < 0·001) in units with 30 mm glucose. As glucose became depleted, the decrease in ATP to levels below 3 μmol/10(11) plts was associated with an increase in both annexin V binding and intracellular free calcium. In units lacking exogenous acetate, ATP levels on day 10 were 5·2 ± 1·5 μmol/10(11) plts compared with 2·7 ± 0·9 μmol/10(11) plts in units with 56 mm acetate (P = 0·006). Higher concentrations of exogenous acetate were associated with a lower hypotonic shock response and higher surface expression of CD62P suggestive of a dose dependency.

CONCLUSION

Under current physical storage conditions, glucose appears necessary for the maintenance of platelets stored as concentrates in minimal volumes of plasma. The addition of acetate was associated with increased platelet activation and reduced ATP levels.

Reduction of vitamin A deficiency and anemia in pregnancy after implementing proposed prenatal nutritional assistance

INTRODUCTION

Micronutrient deficiency is an unquestionable public health problem, specially anemia and vitamin A deficiency (VAD). This is due to the collective dimension of these carencies, which reflects on morbimortality rates in the maternal and infant group.

OBJECTIVE

to evaluate the impact of a proposal for prenatal nutritional assistance, comparing the prevalence of anemia and VAD, in pre-intervention (GI) and intervention (GII) groups.

METHODS

this is a prospective intervention study in a cohort of pregnant women. The GI group was made up of 225 the GII group of 208 pregnant adults and their respective newborns, attended a Public Maternity Ward in Rio de Janeiro, Brazil. Concentration of hemoglobin was used to diagnose anemia and a standardized interview to diagnose night blindness (XN).

RESULTS AND CONCLUSION

after adjusting for confounding variables, through logistic regression, the protective effect of intervention at the onset of anemia (OR = 0.420; IC 95% = 0.251-0.702), with a significant reduction in prevalence, of 28.4% in the GI to 16.8% in the GII, also observed at the onset of XN (OR = 0.377; IC95% = 0.187- 0.759), with a reduction in prevalence of 18.7 % in the GI to 6.2% in the GII. Nutritional intervention has a beneficial effect on maternal health, reducing nutritional deficiencies most prevalent during pregnancy and the impact of these on the obstetric ailment.

Making hard choices easier: a prospective, multicentre study to assess the efficacy of a fertility-related decision aid in young women with early-stage breast cancer

BACKGROUND

Fertility is a priority for many young women with breast cancer. Women need to be informed about interventions to retain fertility before chemotherapy so as to make good quality decisions. This study aimed to prospectively evaluate the efficacy of a fertility-related decision aid (DA).

METHODS

A total of 120 newly diagnosed early-stage breast cancer patients from 19 Australian oncology clinics, aged 18-40 years and desired future fertility, were assessed on decisional conflict, knowledge, decision regret, and satisfaction about fertility-related treatment decisions. These were measured at baseline, 1 and 12 months, and were examined using linear mixed effects models.

RESULTS

Compared with usual care, women who received the DA had reduced decisional conflict (β=-1.51; 95%CI: -2.54 to 0.48; P=0.004) and improved knowledge (β=0.09; 95%CI: 0.01-0.16; P=0.02), after adjusting for education, desire for children and baseline uncertainty. The DA was associated with reduced decisional regret at 1 year (β=-3.73; 95%CI: -7.12 to -0.35; P=0.031), after adjusting for education. Women who received the DA were more satisfied with the information received on the impact of cancer treatment on fertility (P<0.001), fertility options (P=0.005), and rated it more helpful (P=0.002), than those who received standard care.

CONCLUSION

These findings support widespread use of this DA shortly after diagnosis (before chemotherapy) among younger breast cancer patients who have not completed their families.

Evolving fisher kernels for biological sequence classification

Fisher kernels have been successfully applied to many problems in bioinformatics. However, their success depends on the quality of the generative model upon which they are built. For Fisher kernel techniques to be used on novel problems, a mechanism for creating accurate generative models is required. A novel framework is presented for automatically creating domain-specific generative models that can be used to produce Fisher kernels for support vector machines (SVMs) and other kernel methods. The framework enables the capture of prior knowledge and addresses the issue of domain-specific kernels, both of which are current areas that are lacking in many kernel-based methods. To obtain the generative model, genetic algorithms are used to evolve the structure of hidden Markov models (HMMs). A Fisher kernel is subsequently created from the HMM, and used in conjunction with an SVM, to improve the discriminative power. This paper investigates the effectiveness of the proposed method, named GA-SVM. We show that its performance is comparable if not better than other state of the art methods in classifying secretory protein sequences of malaria. More interestingly, it showed better results than the sequence-similarity-based approach, without the need for additional homologous sequence information in protein enzyme family classification. The experiments clearly demonstrate that the GA-SVM is a novel way to find features with good performance from biological sequences, that does not require extensive tuning of a complex model.