Isolation of Distinct Networks Driving Action and Cognition in Psychomotor Processes

BACKGROUND

Psychomotor disturbances are observed across psychiatric disorders and often manifest as psychomotor slowing, agitation, disorganized behavior, or catatonia. Psychomotor function includes both cognitive and motor components, but the neural circuits driving these subprocesses and how they relate to symptoms have remained elusive for centuries.

METHODS

We analyzed data from the HCP-EP (Human Connectome Project for Early Psychosis), a multisite study of 125 participants with early psychosis and 58 healthy participants with resting-state functional magnetic resonance imaging and clinical characterization. Psychomotor function was assessed using the 9-hole pegboard task, a timed motor task that engages mechanical and psychomotor components of action, and tasks assessing processing speed and task switching. We used multivariate pattern analysis of whole-connectome data to identify brain correlates of psychomotor function.

RESULTS

We identified discrete brain circuits driving the cognitive and motor components of psychomotor function. In our combined sample of participants with psychosis (n = 89) and healthy control participants (n = 52), the strongest correlates of psychomotor function (pegboard performance) (p < .005) were between a midline cerebellar region and left frontal region and presupplementary motor area. Psychomotor function was correlated with both cerebellar-frontal connectivity (r = 0.33) and cerebellar-presupplementary motor area connectivity (r = 0.27). However, the cognitive component of psychomotor performance (task switching) was correlated only with cerebellar-frontal connectivity (r = 0.19), whereas the motor component (processing speed) was correlated only with cerebellar-presupplementary motor area connectivity (r = 0.15), suggesting distinct circuits driving unique subprocesses of psychomotor function.

CONCLUSIONS

We identified cerebellar-cortical circuits that drive distinct subprocesses of psychomotor function. Future studies should probe relationships between cerebellar connectivity and psychomotor performance using neuromodulation.

A preliminary choroid plexus volumetric study in individuals with psychosis

The choroid plexus (ChP) is part of the blood-cerebrospinal fluid barrier, regulating brain homeostasis and the brain's response to peripheral events. Its upregulation and enlargement are considered essential in psychosis. However, the timing of the ChP enlargement has not been established. This study introduces a novel magnetic resonance imaging-based segmentation method to examine ChP volumes in two cohorts of individuals with psychosis. The first sample consists of 41 individuals with early course psychosis (mean duration of illness = 1.78 years) and 30 healthy individuals. The second sample consists of 30 individuals with chronic psychosis (mean duration of illness = 7.96 years) and 34 healthy individuals. We utilized manual segmentation to measure ChP volumes. We applied ANCOVAs to compare normalized ChP volumes between groups and partial correlations to investigate the relationship between ChP, LV volumes, and clinical characteristics. Our segmentation demonstrated good reliability (.87). We further showed a significant ChP volume increase in early psychosis (left: p < .00010, right: p < .00010) and a significant positive correlation between higher ChP and higher LV volumes in chronic psychosis (left: r = .54, p = .0030, right: r = .68; p < .0010). Our study suggests that ChP enlargement may be a marker of acute response around disease onset. It might also play a modulatory role in the chronic enlargement of lateral ventricles, often reported in psychosis. Future longitudinal studies should investigate the dynamics of ChP enlargement as a promising marker for novel therapeutic strategies.

Hippocampal Subfield Volumes Predict Disengagement from Maintenance Treatment in First Episode Schizophrenia

OBJECTIVES

Disengagement from treatment is common in first episode schizophrenia (FES) and is associated with poor outcomes. Our aim was to determine whether hippocampal subfield volumes predict disengagement during maintenance treatment of FES.

METHODS

FES patients were recruited from sites in Boston, New York, Shanghai, and Changsha. After stabilization on antipsychotic medication, participants were randomized to add-on citalopram or placebo and followed for 12 months. Demographic, clinical and cognitive factors at baseline were compared between completers and disengagers in addition to volumes of hippocampal subfields.

RESULTS

Baseline data were available for 95 randomized participants. Disengagers (n = 38, 40%) differed from completers (n = 57, 60%) by race (more likely Black; less likely Asian) and in more alcohol use, parkinsonism, negative symptoms and more impairment in visual learning and working memory. Bilateral dentate gyrus (DG), CA1, CA2/3 and whole hippocampal volumes were significantly smaller in disengagers compared to completers. When all the eight volumes were entered into the model simultaneously, only left DG volume significantly predicted disengagement status and remained significant after adjusting for age, sex, race, intracranial volume, antipsychotic dose, duration of untreated psychosis, citalopram status, alcohol status, and smoking status (P < .01). Left DG volume predicted disengagement with 57% sensitivity and 83% specificity.

CONCLUSIONS

Smaller left DG was significantly associated with disengagement status over 12 months of maintenance treatment in patients with FES participating in a randomized clinical trial. If replicated, these findings may provide a biomarker to identify patients at risk for disengagement and a potential target for interventions.

Effect of citalopram on hippocampal volume in first-episode schizophrenia: Structural MRI results from the DECIFER trial

Hippocampal volume loss is prominent in first episode schizophrenia (FES) and has been associated with poor clinical outcomes and with BDNF genotype; antidepressants are believed to reverse hippocampal volume loss via release of BDNF. In a 12-month, placebo-controlled add-on trial of the antidepressant, citalopram, during the maintenance phase of FES, negative symptoms were improved with citalopram. We now report results of structural brain imaging at baseline and 6 months in 63 FES patients (34 in citalopram group) from the trial to assess whether protection against hippocampal volume loss contributed to improved negative symptoms with citalopram. Hippocampal volumetric integrity (HVI) did not change significantly in the citalopram or placebo group and did not differ between treatment groups, whereas citalopram was associated with greater volume loss of the right CA1 subfield. Change in cortical thickness was associated with SANS change in 4 regions (left rostral anterior cingulate, right frontal pole, right cuneus, and right transverse temporal) but none differed between treatment groups. Our findings suggest that minimal hippocampal volume loss occurs after stabilization on antipsychotic treatment and that citalopram's potential benefit for negative symptoms is unlikely to result from protection against hippocampal volume loss or cortical thinning.

AB1360-HPR A MODEL TO IMPROVE MINORITY PATIENT RECRUITMENT IN LUPUS CLINICAL TRIALS - THE AMERICAN COLLEGE OF RHEUMATOLOGY MIMICT PROJECT EXPERIENCE

Background:

In the US, African Americans and Latinos are underrepresented in lupus clinical trials (LCTs),1despite experiencing the greatest lupus disease burden.2,3Low participation in LCTs results in inadequate data on treatment effectiveness for minority patients, and fewer opportunities for better care and treatment options.1Only one percent of minority patients are referred to clinical trials each year.4Provider barriers to making referrals include limited time and unfamiliarity with lupus and LCT opportunities.4Using US fedral grant funds, the American College of Rheumatology (ACR) developed MIMICT, a two-part model with associated materials to address provider-side LCT referral barriers. The materials include a toolkit for clinical trial sites and an educational toolkit for providers.

Objectives:

Our objectives are to:

•Describe the US LCTs disparities.

•Discuss the research methodology to evaluate the two-part MIMICT model.

•Assess the feasibility of the model to increase minority involvement in clinical trials.

Methods:

We designed two studies to evaluate the MIMICT model.The first study used an online, pretest/posttest, two-group evaluation approach to assess the extent to which the educational toolkit increased providers‘ knowledge, attitudes, self-efficacy, and behavioral intentions to refer minority patients to clinical trial. We conducted the study in 2018 with primary care providers (PCPs) and again in 2019/2020 with speciality providers. The second study used a longitudinal, mised methods, case-study approach to explore the real-world use of the toolkits with clinical trial site teams at two university medical centers.

Results:

In the first study,among MIMCT-exposed PCPs, mean scores indicated statistical significance at p≤0.001 with more knowledge about referring [55.84 (sd=23.51) vs 41.76 (sd=19.98)], more self-efficacy to refer [55.00 (sd=37.22) vs. 37.99 (sd=34.42)], and more intentions to refer [61.36 (43.85) vs. 33.41 (41.16)] African American patients to LCTs among the treatment group than the control group, respectively. This presentation will discuss additional data comparing the study in 2018 and the study in 2019/2020 and look comparatively at outcomes across provider type.

In the second study, we found that the driver for successful engagemetn of providers and their subsequent use of the educational toolkit was the development of a trusting relationship between the clinical trial site teams and providers in the community. The development of trust took repeated and varied modes of contact, which we will discuss in-depth.

Conclusion:

The MIMICT educational toolkit increase knowledge, self-efficacy, and intentions to refer lupus patients to LCTs. However, building trust between LCT sites and local providers takes time and repeated outreach, but the potential benefits to medicine and minority health are substantial.

References:

[1]The Society for Women’s Health Research. (2011). Dialogues on diversifying clinical trials: successful strategies for engaging women and minorities in clinical trials. Washington, DC: Food and Drug Administration, Office of Women’s Health.

[2]Falasinnu, T., Chaichian, Y., Bass, M. B., & Simard, J. F. (2018). The representation of gender and race/ethnic groups in randomized clinical trials of individuals with sytemic lupus erythematosus.Current Rheumatology Reports, 20(4).

[3]Pons-Estel, G. J., Alarcon, G. S., Scofield, L., Reinlib, L., & Cooper, G. S. (2010). Understanding the epidemiological progression of systemic lupus erythematosus.Seminars in Arthritis and Rheumatism, 39(4).

[4]Korieth, K. (2016). Engaging healthcare providers as research facilitators.The CenterWatch Monthly, 23,1-5.

Disclosure of Interests:

None declared

Regional GABA Concentrations Modulate Inter-network Resting-state Functional Connectivity

Coordinated activity within and differential activity between large-scale neuronal networks such as the default mode network (DMN) and the control network (CN) is a critical feature of brain organization. The CN usually exhibits activations in response to cognitive tasks while the DMN shows deactivations; in addition, activity between the two networks is anti-correlated at rest. To address this issue, we used functional MRI to measure whole-brain BOLD signal during resting-state and task-evoked conditions, and MR spectroscopy (MRS) to quantify GABA and glutamate concentrations, in nodes within the DMN and CN (MPFC and DLPFC, respectively) in 19 healthy individuals at 3 Tesla. We found that GABA concentrations in the MPFC were significantly associated with DMN deactivation during a working memory task and with anti-correlation between DMN and CN at rest and during task performance, while GABA concentrations in the DLPFC weakly modulated DMN-CN anti-correlation in the opposite direction. Highlighting specificity, glutamate played a less significant role related to brain activity. These findings indicate that GABA in the MPFC is potentially involved in orchestrating between-network brain activity at rest and during task performance.

Air pollution and hippocampal atrophy in first episode schizophrenia

Air pollution has recently been linked to central nervous system (CNS) diseases, possibly mediated by inflammation and oxidative stress. Hippocampal atrophy in individuals with first episode schizophrenia (FES) has also been associated with biomarkers of inflammation and oxidative stress, whereas hippocampal atrophy was not observed in matched healthy controls with similar biomarker levels of inflammation and oxidative stress. Fine particulate matter (PM2.5), one component of air pollution, is most strongly implicated in CNS disease. The present study examined the association between PM2.5 and hippocampal volume in individuals with FES who participated in a 52-week placebo-controlled clinical trial of citalopram added to clinician-determined antipsychotic treatment at four sites in the US and China. Left hippocampal volumetric integrity (LHVI; inversely related to atrophy) was measured at baseline and week 52 using an automated highly-reliable algorithm. Mean annual PM2.5 concentrations were obtained from records compiled by the World Health Organization. The relationships between baseline LHVI and PM2.5 and change in LHVI and PM2.5 were evaluated using regression analyses. 89 participants completed imaging at baseline and 46 participants completed imaging at week 52. Mean annual PM2.5 was significantly associated with both baseline LHVI and change in LHVI after controlling for age, sex, baseline LHVI, duration of untreated psychosis and baseline antipsychotic medication dose. Air pollution may contribute to the progression of hippocampal atrophy after a first episode of illness, but these findings should be considered preliminary since other unmeasured factors may have differed between cities and contributed to the observed effect.

The life-course approach to vaccination: Harnessing the benefits of vaccination throughout life

Vaccination beyond childhood brings significant benefits at the individual, community and socio-economic levels. Despite this, immunisation programmes often fail to deliver the vaccines which could protect those at risk of vaccine-preventable diseases. In this commentary, we argue that the benefits of vaccination beyond childhood must be more widely understood and furthermore, that action must be taken by policymakers, healthcare professionals and patient and civil society organisations to ensure that the benefits of vaccination are fully realised. We outline five areas where change is needed to ensure vaccination across the life-course becomes truly embedded in national immunisation programmes. This includes investing in robust data collection and analysis; ensuring coordinated, multidisciplinary leadership from the top; engaging healthcare professionals; changing public perceptions of vaccination; and integrating vaccination into schools and workplaces.

Lessons from an online vaccine communication project

Most members of the general public use the internet to research health topics. However, the quality of vaccine-related material available online is mixed and internet search engines often bring web users to low-quality anti-vaccine websites. We present a case study of a pro-vaccine information hub launched in 2011. Vaccines Today provides high-quality information about vaccines and diseases, expert interviews, answers to frequently asked questions, parent/patient stories and videos/infographics. Twitter, Facebook, YouTube and Instagram are used to share this content and to engage with various online audiences. This Commentary outlines what works in online communication about vaccines and offers proposals for improving the impact of online vaccine advocacy. The value of networking to boost visibility and search engine ranking is emphasised. Furthermore, we present the case for the sharing and application of best practice in online communication.

The importance of the patient voice in vaccination and vaccine safety-are we listening?

Much has been written about the patient-physician relationship over the years. This relationship is essential in maintaining trust in the complex arena of modern diagnostic techniques, treatment and prevention, including vaccines and vaccine safety. However, a great deal of this material was written from the viewpoint of clinicians and academics. The patient voice may be positive or negative, fragmented or complex. Information sources are weighed and treated differently, according to the value system and risk perceptions of the individual. In post-trust societies, when people have less confidence in health authorities, communication needs to be more than a paternalistic top-down process. Notions of empowerment and individual patient choice are becoming crucial in medical care. The 'voice of the patient', which includes healthy individuals receiving vaccines, needs to be heard, considered and addressed. With respect to childhood immunizations, this will be the voice of the parent or caregiver. The key to addressing any concerns could be to listen more and to develop a communication style that is trust-based and science-informed. Regulatory agencies are encouraging clinical and patient-reported outcomes research under the umbrella of personalized medicine, and this is an important step forward. This paper attempts to reflect the paradigm shift towards increasing attention to the patient voice in vaccination and vaccine safety.

The Global Meningococcal Initiative: global epidemiology, the impact of vaccines on meningococcal disease and the importance of herd protection

INTRODUCTION

The 2015 Global Meningococcal Initiative (GMI) meeting discussed the global importance of meningococcal disease (MD) and its continually changing epidemiology. Areas covered: Although recent vaccination programs have been successful in reducing incidence in many countries (e.g. Neisseria meningitidis serogroup [Men]C in Brazil, MenA in the African meningitis belt), new clones have emerged, causing outbreaks (e.g. MenW in South America, MenC in Nigeria and Niger). The importance of herd protection was highlighted, emphasizing the need for high vaccination uptake among those with the highest carriage rates, as was the need for boosters to maintain individual and herd protection following decline of immune response after primary immunization. Expert commentary: The GMI Global Recommendations for Meningococcal Disease were updated to include a recommendation to enable access to whole-genome sequencing as for surveillance, guidance on strain typing to guide use of subcapsular vaccines, and recognition of the importance of advocacy and awareness campaigns.

Insensible water loss from the Jostra Quadrox D oxygenator: an in vitro study

Extracorporeal membrane oxygenation (ECMO) has been shown to improve outcomes in neonatal patients with respiratory and/or cardiac failure. Insensible water loss is defined as water loss via evaporation from the skin and respiration. Fluid and electrolyte balance are a primary concern and very challenging in the neonatal patient population. Hypernatremia can result from untreated insensible water loss, leading to possible cerebral complications. A new type of fiber used in the Jostra Quadrox D oxygenator has recently been approved for use in the United States of America. This oxygenator uses a polymethylpentene closed hollow-fiber technology and has been approved for six hours of continuous use by the Federal Drug Administration. The closed hollow-fiber technology may be advantageous for extended use due to the fact that it is a true membrane and plasma leakage will not occur across its surface. The Jostra Quadrox D is an adult-sized oxygenator with a surface area of 1.8 M2. The aim of this study is to discover what the insensible water loss will be from the Jostra Quadrox D when used at blood flows which would mimic those used for a neonatal ECMO patient. The median insensible water loss from the Quadrox D oxygenator at a gas flow rate of two liters per minute(LPM) was 4.0 ± 0.2 ml/hour, at five LPM was 9.8 ± 0.4 ml/hour and at 10 LPM was 20.6 ± 0.7 ml/hour. The daily evaporative water loss from the Jostra Quadrox D can be estimated to be 48.0 ± 2.1 ml for each LPM of sweep gas with a normal saline pump flow rate of 500 ml/min.

The Core Brain Region for Face Processing in Schizophrenia Lacks Face Selectivity

BACKGROUND

Face perception impairment in schizophrenia has long been recognized. However, brain mechanisms underlying this socially important perceptual deficit are not well understood. Previous magnetic resonance imaging (MRI) studies have shown that patients have altered structure in brain regions responsible for processing face information, but functional properties of these brain regions are not clearly determined. A key functional property of the face-processing system--face selectivity--has yet to be evaluated in schizophrenia.

METHODS

We used functional MRI (fMRI) to examine face selectivity of 3 core face-processing regions--fusiform face area (FFA), occipital face area (OFA), and superior temporal sulcus (STS)--in schizophrenia patients (n = 24) and healthy controls (n = 23). To disassociate face-specific processing from general perceptual processing, we compared cortical activations during performance of perceptually equated face and tree detection tasks.

RESULTS

Activation levels of the 3 putative face-processing regions during face detection did not differ between patients and controls, being similar for FFA and OFA and absent for STS. However, face selectivity, indexed by the difference in cortical activation between face and tree detection, was significantly reduced in patients for FFA, especially for low-contrast stimuli. FFA activation and perceptual performance during face detection were associated in patients.

CONCLUSIONS

These results show a lack of face-specific processing in the schizophrenic brain region presumably subserving face perception. This finding suggests boosting visual salience of face images as a potential therapeutic venue for improving face perception in this psychiatric disorder.

Similar changes in cognitions following cognitive-behavioral therapy or escitalopram for major depressive disorder: Implications for mechanisms of change

BACKGROUND

Psychosocial treatments and medications both have been shown to be effective in treating major depressive disorder. We hypothesized that cognitive-behavioral therapy (CBT) would outperform medication on measures of cognitive change.

METHODS

We randomized depressed individuals to 12 weeks of CBT (n = 15) or escitalopram (n = 11). In an intent-to-treat analysis (n = 26), we conducted a repeated measures analysis of variance to examine changes in depressive symptoms (ie, 17-item Hamilton Depression Rating Scale, Beck Depression Inventory), anhedonia (ie, Snaith-Hamilton Pleasure Scale), cognitive measures (ie, Dysfunctional Attitudes Scale, Automatic Thoughts Questionnaire, Perceived Stress Scale), and quality of life (ie, Quality of Life Enjoyment and Satisfaction Questionnaire) at 4 time points: baseline, week 4, week 8, and week 12. Treatment for both groups started at baseline, and patients received either 12 weeks of individual CBT or 12 weeks of escitalopram with flexible dosing (10 to 20 mg).

RESULTS

Collapsing the escitalopram and CBT groups, there were statistically significant pre-post changes on all outcome measures. However, there were no statistically significant differences between treatment groups on any of the outcome measures, including cognitive measures across time points.

CONCLUSIONS

Our results suggest that both CBT and escitalopram have similar effects across a variety of domains and that, in contrast to our a priori hypothesis, CBT and escitalopram were associated with comparable changes on cognitive measures.

Complexin2 modulates working memory-related neural activity in patients with schizophrenia

The specific contribution of risk or candidate gene variants to the complex phenotype of schizophrenia is largely unknown. Studying the effects of such variants on brain function can provide insight into disease-associated mechanisms on a neural systems level. Previous studies found common variants in the complexin2 (CPLX2) gene to be highly associated with cognitive dysfunction in schizophrenia patients. Similarly, cognitive functioning was found to be impaired in Cplx2 gene-deficient mice if they were subjected to maternal deprivation or mild brain trauma during puberty. Here, we aimed to study seven common CPLX2 single-nucleotide polymorphisms (SNPs) and their neurogenetic risk mechanisms by investigating their relationship to a schizophrenia-related functional neuroimaging intermediate phenotype. We examined functional MRI and genotype data collected from 104 patients with DSM-IV-diagnosed schizophrenia and 122 healthy controls who participated in the Mind Clinical Imaging Consortium study of schizophrenia. Seven SNPs distributed over the whole CPLX2 gene were tested for association with working memory-elicited neural activity in a frontoparietal neural network. Three CPLX2 SNPs were significantly associated with increased neural activity in the dorsolateral prefrontal cortex and intraparietal sulcus in the schizophrenia sample, but showed no association in healthy controls. Since increased working memory-related neural activity in individuals with or at risk for schizophrenia has been interpreted as 'neural inefficiency,' these findings suggest that certain variants of CPLX2 may contribute to impaired brain function in schizophrenia, possibly combined with other deleterious genetic variants, adverse environmental events, or developmental insults.

Relationship between sleep disturbance and depression, anxiety, and functioning in college students

BACKGROUND

Sleep disturbance (SD) has complex associations with depression, both preceding and following the onset and recurrence of depression. We hypothesized that students with depressive symptoms with SD would demonstrate a greater burden of comorbid psychiatric symptoms and functional impairment compared to students with depressive symptoms without SD.

METHODS

During a mental health screening, 287 undergraduate students endorsed symptoms of depression (Beck Depression Inventory [BDI] ≥ 13) and filled out the following self-report measures: demographic questionnaire, BDI, Anxiety Symptom Questionnaire-intensity and frequency (ASQ), Beck Hopelessness Scale (BHS), Beck Anxiety Inventory (BAI), Quality of Life Enjoyment and Satisfaction Questionnaire (QLESQ), and the Massachusetts General Hospital Cognitive and Physical Functioning Questionnaire (CPFQ). SD was measured using the BDI sleep item #16 dichotomized (score 0: no SD; or score > 0: some SD).

RESULTS

Students with depressive symptoms and SD (n = 220), compared to those without SD (n = 67), endorsed significantly more intense and frequent anxiety and poorer cognitive and physical functioning. Students with depressive symptoms with and without SD did not significantly differ in depressive severity, hopelessness, or quality of life.

CONCLUSIONS

College students with depressive symptoms with SD may experience a greater burden of comorbid anxiety symptoms and hyperarousal, and may have impairments in functioning, compared to students with depressive symptoms without SD. These findings require replication.

An unusual presentation of an ectopic third molar in the condylar region

We describe the case of a 53-year-old patient who presented with an intermittent discharging sinus on his face which, following a number of investigations, was found to be secondary to an ectopic third molar in the condylar region. The ectopic tooth was surgically removed with complete resolution of the facial swelling. This case highlights the possibility of dental pathology presenting with completely unrelated signs and symptoms, and the importance of the clinician maintaining an open mind when it comes to the differential diagnosis of such a presentation.

Alternative Approaches To Target the COX-2 Pathway To Reduce Breast Cancer Metastasis

Background: The cyclooxygenase-2 (COX-2) enzyme is highly expressed in breast cancer and is associated with a poorer prognosis. Past efforts have focused on targeting the COX-2 enzyme with pharmacologic COX-2 inhibitors including celecoxib and rofecoxib. Recent safety concerns have led us to test the hypothesis that targeting downstream members of the COX-2 pathway will be more efficacious and safer. The principle COX-2 product in tumors is prostaglandin E2 (PGE2) which mediates cellular effects by binding to four distinct G-protein-coupled receptors designated EP1, EP2, EP3 and EP4.Materials and Methods: Using pharmacologic and genetic approaches and a preclinical model of metastatic, triple-negative (ER, PR, Her-2 negative) breast cancer, we have examined the role of EP4 and EP1 in malignant behavior. We determined the effect of antagonizing either EP1 or EP4 with the pharmacologic antagonists AH23848, ONO-AE3-208 or SC19220 on metastatic ability of line 66.1 or line 410.4 mammary tumor cells injected into syngeneic Balb/cByJ female mice and compared efficacy of receptor antagonists to either a COX-2 inhibitor (celecoxib) or a dual COX-1/COX-2 inhibitor (indomethacin). We also reduced the expression of either receptor by tranducing tumor cells with specific shRNAs and determined the effect of EP gene silencing on metastatic potential. Using mice with specific deletions of immune effector cells, we also examined the role of host immunity in controlling tumor metastasis.Results: Inhibition of EP4 receptor signaling with the selective EP4 antagonists AH23848 or ONO-AE3-208 limits breast cancer metastasis to the same degree as achieved with a COX inhibitor. Likewise, gene silencing of EP4 with a vector expressing EP4 siRNA also limits metastatic capacity. The therapeutic effect of EP4 blockade is compromised in mice lacking functional Natural Killer cells and NK-mediated lysis of mammary tumor cells is enhanced in the presence of EP4 antagonists. Conversely, blocking EP1 with either the pharmacologic antagonist SC19220 or by gene-silencing promotes tumor metastasis. The expansion of tumors implanted into the mammary fat pad was not affected by modulating EP expression levels, indicating that EP1 functions as a suppressor of metastasis. Interestingly, breast tumors from African-American women express significantly less EP1 than tumors from Caucasian women, suggesting that EP1 could contribute to breast cancer disparities. Ongoing studies are evaluating the relationship of EP expression to long term survival.Discussion: These data support the hypothesis that therapeutic targeting of EP4 may be an alternative approach to the use of COX inhibitors to limit metastatic disease. The mechanism of metastasis control is likely to involve activation of Natural Killer cells. Shifting the balance towards activation of the metastasis suppressor EP1 could be an additional means to reduce breast cancer metastasis.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6140.

High-resolution melt analysis for the detection of a mutation associated with permethrin resistance in a population of scabies mites

Permethrin as a topical acaricide cream is widely used to treat scabies. The neuronal voltage-sensitive sodium channel (Vssc), necessary for the generation of action potentials in excitable cells, is the target of pyrethroid acaricides such as permethrin. Pyrethroid resistance has been linked to specific mutations in the Vssc gene. Following the partial sequencing of the Vssc gene in the scabies mite Sarcoptes scabiei (L.) (Astigmata: Sarcoptidae), we compared Vssc gene sequences from permethrin-sensitive and -tolerant S. scabiei var. canis Gerlach mites, and identified a G to A single nucleotide polymorphism (SNP) in permethrin-tolerant mites resulting in an amino acid change from glycine to aspartic acid in domain III S6. The mutation is in a region of the gene where mutations have been identified in a range of pyrethroid-resistant arthropods. Results of in vitro permethrin exposure assays showed that survival rates for mites bearing the mutation were similar to those previously reported for mites from human subjects where clinical tolerance to permethrin had been observed. A real-time polymerase chain reaction-high-resolution melt (PCR-HRM) assay was developed to detect this SNP. This assay provides a useful methodology for screening for this and other mutations associated with permethrin resistance in scabies mite populations and thus facilitates surveillance for acaricide resistance.

Response to ciclosporin treatment in Ethiopian and Nepali patients with severe leprosy Type 1 reactions

Leprosy type 1 reactions (T1R) are immune-mediated events with inflammation of peripheral nerves and skin. We report the clinical outcomes of a closely monitored open prospective trial in which eight Nepali and 33 Ethiopian patients with T1Rs were treated with an Indian generic formulation of ciclosporin (Cn; 5-7.5 mg/kg/day) for 12 weeks and followed up for 24 weeks after starting treatment. Outcomes were measured using a clinical severity score. Among the Nepalis, 75-100% improved in all acute clinical parameters; 67-100% patients maintained improvement, except for those with acute sensory nerve impairment among whom 67% relapsed after stopping treatment. The skin lesions of all Ethiopians on 5 mg/kg/day of Cn improved and 50-60% had peripheral nerve function improvement. Most Ethiopians needed a higher dose of Cn to improve nerve impairment and neuritis, and 50-78% of them developed worse clinical severity scores when Cn was stopped. Four Ethiopians and two Nepalis developed elevated serum creatinine levels on 7.5 mg/kg/day Cn, and three (9%) Ethiopians developed treatable hypertension. This suggests that Cn monotherapy is an effective treatment for severe T1R with few adverse effects. A dose of 5 mg/kg/day seems efficacious in Nepalis, but a higher dose may be required in Ethiopian patients.

Livestock welfare product claims: The emerging social context

An increasing number of product claims about food animal welfare or well-being have appeared in the global food industry and global market in recent years. These claims have significant consequences for producers, processors, transporters, retailers, consumers, and the animals themselves. Furthermore, recent restructuring of the global food industry has altered the power relationships of various actors. Regulation of the industry is moving toward greater private control, and the power of retailers has dramatically increased. The changing structure of the industry carries implications both in terms of how standards are created and in terms of the types of standards themselves. The purpose of this article is to provide a greater understanding of how these product claims are made, their implications, and the challenges they present.

Quantitative detection of protein expression in single cells using droplet microfluidics

We demonstrate that single cells can be controllably compartmentalized within aqueous microdroplets; using such an approach we perform high-throughput screening by detecting the expression of a fluorescent protein in individual cells with simultaneous measurement of droplet size and cell occupancy.

WITHDRAWN: Multi-center evaluation of analytical performance of the microparticle enzyme immunoassay for sirolimus

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Clin. Biochem. 39 (2006) 378-386, doi:10.1016/j.clinbiochem.2006.01.017. The duplicate article has therefore been withdrawn. This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.

Vasopressin and oxytocin secretion in response to the consumption of ecstasy in a clubbing population

Despite the common use of MDMA (ecstasy) in the UK, the mechanism underlying associated potentially fatal cerebral oedema is unclear. We used a new experimental approach working directly with clubbers to perform a study on 30 (17 male) experienced clubbers (mean 6.6 years of clubbing). Pre- and post-clubbing measurements were performed to compare plasma levels of pituitary hormones (vasopressin, oxytocin), plasma and urine osmolality, urinary pH, and plasma sodium and urea. Ecstasy consumption was confirmed by using urinary drug screening pre- and post-clubbing. MDMA was detected in the urine samples of 17 subjects, three of which tested positive during pre-clubbing tests. Mean plasma vasopressin concentration increased in the MDMA group (1.28 +/- 0.29 to 1.43 +/- 0.41 pmol/l), but fell in other participants (1.23 +/- 0.42 to 1.16 +/- 0.0.34 pmol/l). Similarly, mean plasma oxytocin concentrations increased after ingestion of MDMA (2.02 +/- 0.29 to 2.43 +/- 0.24 pmol/l), but fell in the group that did not use MDMA (2.17 +/- 0.36 pmol/l to 1.89 +/- 0.37 pmol/l). There was a significant group by time interaction for plasma osmolality and plasma sodium (p = 0.001 and p = 0.003, respectively) and between change in urinary osmolality (p < 0.001) and MDMA use, with the pattern of change being consistent with the induction of inappropriate vasopressin secretion (also known as SIADH) by MDMA. This report demonstrates SIADH in ecstasy-using "clubbers", which has important clinical implications.

Multi-center evaluation of analytical performance of the microparticle enzyme immunoassay for sirolimus

OBJECTIVES

This study evaluated the analytical characteristics of the new Abbott microparticle enzyme immunoassay (MEIA) for sirolimus.

DESIGN AND METHODS

The protocol consisted of nine sections: evaluation of antibody specificity, linearity, detection limit, quantification limit, endogenous interferents, exogenous interferents, precision, proficiency testing panel, and method comparison.

RESULTS

The mean analytical detection limit was 0.68 microg/L. The sirolimus concentration corresponding to a total CV of 20% was 1.5 microg/L. Linearity of response was demonstrated across the dynamic range of the assay. Total precision (CVs) at QC control levels from 5 to 22 microg/L ranged from 5.7 to 12.6%. Assay standardization was found to be in good agreement with LC/MS/MS as compared with target values for spiked sirolimus proficiency samples from an international sirolimus proficiency testing program. Good correlations (R values) of the immunoassay were observed in comparisons to LC/MS/MS. R values tended to be lower in comparisons with LC/UV methods. Across both LC-based methods and all study sites, there was approximately 25% overall positive slope bias due to cross reactivity of the MEIA antibody to metabolites of sirolimus. The assay cross-reactivity to metabolites of sirolimus parent drug ranged from 6 to 63%. Assay interferences were minimal with the exception of hematocrit, which presented a negative relationship to measured sirolimus concentration.

CONCLUSIONS

The MEIA demonstrated acceptable analytical characteristics for use for routine monitoring of sirolimus immunosuppressive therapy, and is a viable alternative to HPLC-based methods for sirolimus monitoring.

A methodology for the evaluation of disinfection technologies

There are several concerns associated with the use of chlorine for potable water disinfection. These are the resistance of certain pathogens, the formation of toxic disinfection by-products and the adverse effects on aesthetic water quality. Owing to these concerns the water industry is continually reviewing alternative disinfection technologies. A methodology has been devised that will aid the water industry in evaluating the potential of these technologies. The methodology uses seven criteria to evaluate the technologies, these are: inactivation efficiency, disinfection byproduct (DBP) formation, toxicity, aesthetic water quality, cost, scalability and residual maintenance. Each criterion is assessed by associated questions in order of importance in accordance with a protocol. The criteria are evaluated using UK water quality regulations as standards. Ultraviolet (UV) disinfection was used as an example to demonstrate the methodology. UV was shown to meet all the criteria apart from the provision of a residual disinfectant. Several other disinfection technologies were evaluated using the methodology. Direct electrochemical disinfection and mixed oxidant generators were identified as having the most potential for replacing chlorination.

Genetic epidemiology of Sarcoptes scabiei (Acari: Sarcoptidae) in northern Australia

Utilising three hypervariable microsatellite markers we have previously shown that scabies mites on people are genetically distinct from those on dogs in sympatric populations in northern Australia. This had important ramifications on the formulation of public health control policies. In contrast phylogenetic analyses using mitochondrial markers on scabies mites infecting multiple animal hosts elsewhere in the world could not differentiate any genetic variation between mite haplotype and host species. Here we further analyse the intra-specific relationship of Sarcoptes scabiei var. hominis with S. scabiei var. canis by using both mitochondrial DNA and an expanded nuclear microsatellite marker system. Phylogenetic studies using sequences from the mitochondrial genes coding for 16S rRNA and Cytochrome Oxidase subunit I demonstrated significant relationships between S. scabiei MtDNA haplotypes, host species and geographical location. Multi-locus genotyping using 15 microsatellite markers substantiated previous data that gene flow between scabies mite populations on human and dog hosts is extremely rare in northern Australia. These data clearly support our previous contention that control programs for human scabies in endemic areas with sympatric S. scabiei var. hominis and var. canis populations must focus on human-to-human transmission. The genetic division of dog and human derived scabies mites also has important implications in vaccine and diagnostic test development as well as the emergence and monitoring of drug resistance in S. scabiei in northern Australia.