Early deficits in an in vitro striatal microcircuit model carrying the Parkinson's GBA-N370S mutation

Understanding medium spiny neuron (MSN) physiology is essential to understand motor impairments in Parkinson's disease (PD) given the architecture of the basal ganglia. Here, we developed a custom three-chambered microfluidic platform and established a cortico-striato-nigral microcircuit partially recapitulating the striatal presynaptic landscape in vitro using induced pluripotent stem cell (iPSC)-derived neurons. We found that, cortical glutamatergic projections facilitated MSN synaptic activity, and dopaminergic transmission enhanced maturation of MSNs in vitro. Replacement of wild-type iPSC-derived dopamine neurons (iPSC-DaNs) in the striatal microcircuit with those carrying the PD-related GBA-N370S mutation led to a depolarisation of resting membrane potential and an increase in rheobase in iPSC-MSNs, as well as a reduction in both voltage-gated sodium and potassium currents. Such deficits were resolved in late microcircuit cultures, and could be reversed in younger cultures with antagonism of protein kinase A activity in iPSC-MSNs. Taken together, our results highlight the unique utility of modelling striatal neurons in a modular physiological circuit to reveal mechanistic insights into GBA1 mutations in PD.

Tau depletion in human neurons mitigates Aβ-driven toxicity

Alzheimer's disease (AD) is an age-related neurodegenerative condition and the most common type of dementia, characterised by pathological accumulation of extracellular plaques and intracellular neurofibrillary tangles that mainly consist of amyloid-β (Aβ) and hyperphosphorylated tau aggregates, respectively. Previous studies in mouse models with a targeted knock-out of the microtubule-associated protein tau (Mapt) gene demonstrated that Aβ-driven toxicity is tau-dependent. However, human cellular models with chronic tau lowering remain unexplored. In this study, we generated stable tau-depleted human induced pluripotent stem cell (iPSC) isogenic panels from two healthy individuals using CRISPR-Cas9 technology. We then differentiated these iPSCs into cortical neurons in vitro in co-culture with primary rat cortical astrocytes before conducting electrophysiological and imaging experiments for a wide range of disease-relevant phenotypes. Both AD brain derived and recombinant Aβ were used in this study to elicit toxic responses from the iPSC-derived cortical neurons. We showed that tau depletion in human iPSC-derived cortical neurons caused considerable reductions in neuronal activity without affecting synaptic density. We also observed neurite outgrowth impairments in two of the tau-depleted lines used. Finally, tau depletion protected neurons from adverse effects by mitigating the impact of exogenous Aβ-induced hyperactivity, deficits in retrograde axonal transport of mitochondria, and neurodegeneration. Our study established stable human iPSC isogenic panels with chronic tau depletion from two healthy individuals. Cortical neurons derived from these iPSC lines showed that tau is essential in Aβ-driven hyperactivity, axonal transport deficits, and neurodegeneration, consistent with studies conducted in Mapt-/- mouse models. These findings highlight the protective effects of chronic tau lowering strategies in AD pathogenesis and reinforce the potential in clinical settings. The tau-depleted human iPSC models can now be applied at scale to investigate the involvement of tau in disease-relevant pathways and cell types.

Calcium dysregulation combined with mitochondrial failure and electrophysiological maturity converge in Parkinson's iPSC-dopamine neurons

Parkinson's disease (PD) is characterized by a progressive deterioration of motor and cognitive functions. Although death of dopamine neurons is the hallmark pathology of PD, this is a late-stage disease process preceded by neuronal dysfunction. Here we describe early physiological perturbations in patient-derived induced pluripotent stem cell (iPSC)-dopamine neurons carrying the GBA-N370S mutation, a strong genetic risk factor for PD. GBA-N370S iPSC-dopamine neurons show an early and persistent calcium dysregulation notably at the mitochondria, followed by reduced mitochondrial membrane potential and oxygen consumption rate, indicating mitochondrial failure. With increased neuronal maturity, we observed decreased synaptic function in PD iPSC-dopamine neurons, consistent with the requirement for ATP and calcium to support the increase in electrophysiological activity over time. Our work demonstrates that calcium dyshomeostasis and mitochondrial failure impair the higher electrophysiological activity of mature neurons and may underlie the vulnerability of dopamine neurons in PD.

P-414 Ultrastructural and functional defects in cilia of endometrial glands from women with reproductive failure

Study question

Do endometrial gland factors influence pregnancy success?

Summary answer

Increased proportion of cilia defects during the window of implantation in endometrial glands from women with reproductive failure compared to controls

What is known already

Endometrial glands are important for embryo implantation and successful pregnancy. There is an unmet clinical need to relate endometrial gland structure to function, identify markers for reproductive failure and targets for therapeutic interventions. Ciliated epithelial cells in the endometrium are a distinct cell type with a particular cell transcriptomic signature. Cilia defects have been reported in endometrial glands from women with reproductive failure however, a quantitative study of cilia defects in endometrial glands is yet to be established.

Study design, size, duration

An observational study comparing women with subfertility, recurrent pregnancy loss and controls

Participants/materials, setting, methods

Endometrial samples were collected during the implantation period from fertile controls (n = 10), women with subfertility (n = 11) and women with recurrent pregnancy loss (n = 15). Ciliated cells in endometrial glands were imaged by transmission electron microscopy and the proportion of cilia defects were quantified and compared between study groups. Endometrial glands were isolated from endometrial biopsies and the cilia beat frequency of ciliated cells was quantified by high-speed video analysis.

Main results and the role of chance

Our study reports a significant increase in the proportion of cilia ultrastructural defects in endometrial glands from women with subfertility versus fertile controls (P < 0.05). Cilia defects included microtubule disarrangement, transposition and loss of cilia inner dynein arm motor proteins. Ciliated cells in endometrial glands from women with recurrent pregnancy loss demonstrated a higher proportion of defects compared to fertile controls but this did not reach statistical significance (P = 0.07). A significant decrease in cilia beat frequency was reported in ciliated cells of endometrial glands from women with subfertility compared to fertile controls (P < 0.05).

Limitations, reasons for caution

This is an observational study with a relatively small sample size however, the participants in the study and control groups were matched for age, BMI and menstrual cycle characteristics.

Wider implications of the findings

This study quantified ultrastructural and functional differences of ciliated cells in endometrial glands from women with reproductive failure. Endometrial glands with perturbed cilia structure and function may be non-conductive to successful pregnancy. Differences in endometrial gland cilia could be used to identify a perturbed endometrium and develop targeted therapies.

Trial registration number

not applicable

Neurons derived from individual early Alzheimer's disease patients reflect their clinical vulnerability

Establishing preclinical models of Alzheimer's disease that predict clinical outcomes remains a critically important, yet to date not fully realized, goal. Models derived from human cells offer considerable advantages over non-human models, including the potential to reflect some of the inter-individual differences that are apparent in patients. Here we report an approach using induced pluripotent stem cell-derived cortical neurons from people with early symptomatic Alzheimer's disease where we sought a match between individual disease characteristics in the cells with analogous characteristics in the people from whom they were derived. We show that the response to amyloid-β burden in life, as measured by cognitive decline and brain activity levels, varies between individuals and this vulnerability rating correlates with the individual cellular vulnerability to extrinsic amyloid-β in vitro as measured by synapse loss and function. Our findings indicate that patient-induced pluripotent stem cell-derived cortical neurons not only present key aspects of Alzheimer's disease pathology but also reflect key aspects of the clinical phenotypes of the same patients. Cellular models that reflect an individual's in-life clinical vulnerability thus represent a tractable method of Alzheimer's disease modelling using clinical data in combination with cellular phenotypes.

Strategy for Safe Bronchoscopy during COVID pandemic

Aerosol generating procedures are avoided for COVID-19 patients to lower the risk of transmission to healthcare providers. However, when bronchoscopy is indicated, it remains unclear if the procedure performed under general anesthesia leads to contamination of the surroundings and if standard endoscopy reprocessing methods are effective in eradicating SARS-CoV-2. We share our experience of bronchoscopic retrieval of airway foreign body under general anesthesia in a patient tested positive for novel 2019 coronavirus disease (COVID 19). We focus on anesthesia techniques to minimise aerosolization.

Improving the WHO Surgical Safety Checklist sign-out

BACKGROUND

The WHO Surgical Safety Checklist has been shown to reduce perioperative morbidity and mortality worldwide. There is evidence to suggest that sign-out is the most poorly performed phase of the checklist as it coincides with a period of high workload for team members. This study aimed to see whether modification of this process might result in greater compliance.

METHODS

A controlled longitudinal (before and after) study was performed to evaluate the effect of a modified checklist sign-out on compliance in a single surgical department. Checklist quality was evaluated by measurement of checklist completion, active participation, and team member presence. Workload assessment was performed to identify the optimal moment for the sign-out process. The sign-out process was modified through an iterative multidisciplinary approach, informed by results from the workload assessment. Feedback was obtained through staff surveys.

RESULTS

A total of 185 operations were used, with an intervention group in vascular surgery and a control group in orthopaedics. The optimal timing for sign-out was identified as after final wound closure. The modified sign-out process improved active participation of team members (21 of 34 versus 31 of 34; P = 0.010). In the control group, complete compliance improved (48 of 76 versus 30 of 41; P = 0.041). However, active participation decreased (53 of 76 versus 19 of 41; P = 0.022). No differences were noted between groups in team member presence. Eighteen of 21 staff questioned viewed the modifications positively.

CONCLUSION

The optimal sign-out timing was identified as immediately after final wound closure prior to undraping the patient.

Prevention of docetaxel-associated febrile neutropenia with primary granulocyte colony-stimulating factor in Chinese metastatic hormone-sensitive and castration-resistant prostate cancer patients

INTRODUCTION

Asian prostate cancer (PC) patients are particularly susceptible to docetaxel-related febrile neutropenia (FN). We evaluated primary granulocyte colony-stimulating factor (GCSF) for preventing FN in Chinese patients with metastatic hormone-sensitive PC (mHSPC) and castration-resistant PC (mCRPC).

PATIENTS AND METHODS

Data from two cohorts of 377 Chinese patients with mHSPC (100; 26.5%) and mCRPC (277; 73.5%) treated with docetaxel at six public oncology centres were analysed with multivariate regression. Primary GCSF prophylaxis was defined as administration within 5 days of starting docetaxel. The primary outcome was FN within 21 days of the first docetaxel cycle (1st FN).

RESULTS

Primary GCSF was given to 71 (18.8%) patients. FN occurred in 61 patients (16.2%) including 37 (9.8%) during the first cycle. Among patients who developed 1st cycle FN (n = 37) or not (n = 340), 2 and 69 received primary GCSF (5.4 vs. 20.3%, P = .03). Primary GCSF was associated with an overall reduced risk of 1st cycle FN (odds ratio [OR] = 0.22; 95% confidence interval [CI]: 0.05-0.96, P = .04), and similar trends were observed in the mHSPC (OR = 0.36, P = .35) and mCRPC (OR = 0.16, P = .08) subgroups. Poor Eastern Cooperative Oncology Group performance status (>1) was associated with an increased risk of 1st FN (OR = 3.90; 95% CI: 1.66-9.13, P = .002).

CONCLUSIONS

To alleviate the risk of docetaxel-related FN, primary GCSF prophylaxis is suggested for Asian mCRPC and mHSPC patients, particularly those with poor performance status.

Electrospun nanofibers with surface oriented lamellar patterns and their potential applications

This work shows conclusively that lamellar surface patterns can be obtained with diverse ceramic compositions during electrospinning. The lamellar structure formation is governed by the creation of an outer shell during the thermal treatment of initially uniform cylindrical fibers, consisting of polymer and pre-ceramic compounds. By changing the polymer to pre-ceramic ratio in the electrospinning solution, we demonstrate for the first time a facile way to control the obtained surface structure and the orientation of the lamellas. Furthermore, the lamellar morphology was illustrated in seven different compositions. This report provides a new pathway to obtain unique surface patterns in metal-oxide nanofibers and demonstrates their utilization in different applications. Specifically, we demonstrate the prospect of utilizing Ni-Al-O fibers with lamellar structures as alternative Li-ion battery anodes. In addition, we show the potential of Fe-Al-O fibers as an effective catalyst material.

FRI0354 FACTORS AFFECTING SELF-REPORTED PHYSICAL CTIVITY IN PATIENTS WITH PSORIATIC ARTHRITIS

Background:

Despite the known benefits of exercise1, patients with osteoarthritis (OA) and rheumatoid arthritis (RA) are reported to have low levels of physical activity2. Exercise participation is not well studied in psoriatic arthritis (PsA) cohorts. This study aims to explore which factors predict exercise participation across cohorts and specifically in the PsA cohort.

Objectives:

The primary aim of this study was to determine which clinical factors were predictive of self- reported physical activity levels in patients with PsA. A secondary aim was to explore differences in self-reported physical activity levels amongst patients with PsA, OA and RA.

Methods:

Patients with the diagnosis of PsA, RA or OA are recruited prospectively at two tertiary hospital rheumatology clinics over 12 months. Demographic data is captured by the multi-dimensional health assessment questionnaire, the international physical activity questionnaire short form captures self-reported physical activity and self-efficacy for exercise (SEE) is assessed using the SEE scale. Clinical data including joint count, body mass index and co-morbidities including fibromyalgia are collected for all patients, in addition to PsA specific data including skin and enthesitis indices.

Results:

205 patients (PsA n=62, RA n=83, OA n=60) were recruited across two sites. There was no significant difference in self-reported physical activity between OA, RA and PsA cohorts. Fibromyalgia was present in 30% of each cohort. In patients with PsA, univariate analysis showed that co-existent fibromyalgia, age and self-efficacy for exercise were predictors of physical activity levels. Skin disease and enthesitis were not predictors of physical activity in the PsA cohort.

Table 1.

Univariate Analyses of effect of Clinical Features on Physical Activity levels in PsA

Non-exercisers versus ExercisersOR (95% CI)P-valueLEI1.35 (0.92-1.97)0.127PASI0.8 (0.6-1.07)0.133DLQI1.03 (0.92-1.16)0.589BMI0.97 (0.91-1.04)0.415DAS280.79 (0.55-1.14)0.205Concurrent Fibromyalgia4.46 (1.37-14.49)0.012Age1.05 (1.00-1.10)0.013Self-efficacy for exercise0.97 (0.95-0.99)0.019Pain1.17 (0.99-1.37)0.061Function1.3 (1.02-1.65)0.031Patient global1.14 (0.96-1.34)0.128Depression0.97 (0.51-1.84)0.930Table 2.

Multivariable Analysis on Physical Activity in PsA

Non-exercisers vs ExercisersOR (95% CI)P-valueConcurrent fibromyalgia5.1 (1.44-18.08)0.0117Age1.05 (1.00-1.11)0.0342

Conclusion:

In the PsA cohort, fibromyalgia and age were associated with lower levels of physical activity. DLQI, PASI, LEI did not predict physical activity in PsA. Multivariate analysis showed higher pain levels and lower self-efficacy scores were associated with lower physical activity across arthritis groups.

References:

[1]Der Ananian C, Wilcox S, Watkins K, Saunders RP, Evans AE. (2008). Factors Associated with Exercise Participation in Adults with Arthritis.Journal of Aging and Physical Activity, 16: 125-143

[2]Wilcox S, Der Ananian C, Abbott J, Vrazel J, Ramsey C, Sharpe PA, Brady T. (2006). Perceived Exercise Barriers, Enablers, and Benefits Among Exercising and Nonexercising Adults With Arthritis: Results from a Qualitative Study.Arthritis & Rheumatism, 55(4): 616-627

Acknowledgments:

Joseph Descallar

Dana Georgevsky

Dr Michael Oliffe

Dr Diana Chessman

Department of Rheumatology, Liverpool Hospital NSW Australia

Department of Rheumatology, Westmead Hospital NSW Australia

Disclosure of Interests:

None declared

Prevention of docetaxel-associated febrile neutropenia with primary granulocyte colony-stimulating factors (GCSF) in Chinese metastatic hormonal-sensitive (mHSPC) and castration-resistant prostate cancer (mCRPC)

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Background: Plenty reports suggest Asian prostate cancer patients are more susceptible to docetaxel-related febrile neutropenia (FN). However, primary GCSF prophylaxis is currently not recommended by international guidelines for patients with mCRPC or mHSPC when docetaxel is administered. Therefore, we aim to evaluate the potential benefit of primary GCSF in preventing the potentially life-threatening FN for Chinese mHSPC and mCRPC treated with docetaxel. Methods: Two cohorts (2003-2012 & 2015-2018) that consisted of Chinese patients with mHSPC and mCRPC who had docetaxel at six public oncology centres in Hong Kong were grouped and analysed. Primary GCSF was defined as its administration within 5 days of beginning docetaxel, and its use was at the discretion of oncologists. The primary outcome was FN within 21 days of first cycle of docetaxel (1st FN). Multivariable regression analysis was used. Results: A total of 377 metastatic prostate cancer (mHSPC, n=100 (26%); mCRPC, n=277 (73%)) patients with docetaxel treatment was identified. Primary GCSF was given in 71 (18%) patients. The baseline characteristics were balanced between groups with and without primary GCSF. FN was happened in 61 patients (16%), with 37 (9%) of them at 1st cycle. Primary GCSF were administered in 2 and 69 patients with and without 1st FN, respectively (5.4% vs 20.3%, p=0.03). Primary GCSF was associated with reduced risk of 1st FN (odds ratio (OR), 0.22; 95% CI 0.05 - 0.96; p=0.04) in overall, and a similar trend was observed in both mHSPC (OR, 0.36; p=0.35) and mCRPC (OR, 0.16, p=0.08) subgroups. Besides, among various clinical parameters, poor performance status (ECOG 2-3) was associated with increased risk of 1st FN (OR, 3.90, 95% CI 1.66 – 9.13, p=0.002). Conclusions: Primary GCSF prophylaxis is suggested for Asian mCRPC and mHSPC patients, particularly those with poor performance status, to alleviate the risk of docetaxel-related febrile neutropenia.

Student-Run Clinic Association: The Next Generation of Health System Collaboration

The Student-Run Clinic Association (SRCA) is a pan-Canadian effort to develop new student-run clinics and scale the operation of existing clinics. Student-run clinics utilize a multidisciplinary team of health professional students to provide accessible primary care services to vulnerable and marginalized populations under the supervision of qualified and licensed healthcare providers. The SRCA plays an integral role in building the infrastructure necessary for student-run clinics to be sustainable and scalable across the country. The outcome of our initiative is to enhance equitable, high-quality care to underserved populations in Canada, while simultaneously providing future healthcare providers with experience serving this population.

Direct costs of overdiagnosed asthma: a longitudinal, population-based cohort study in British Columbia, Canada

OBJECTIVES

A current diagnosis of asthma cannot be objectively confirmed in many patients with physician-diagnosed asthma. Estimates of resource use in overdiagnosed cases of asthma are necessary to measure the burden of overdiagnosis and to evaluate strategies to reduce this burden. We assessed differences in asthma-related healthcare resource use between patients with a confirmed asthma diagnosis and those with asthma ruled out.

DESIGN

Population-based, prospective cohort study.

SETTING

Participants were recruited through random-digit dialling of both landlines and mobile phones in the province of British Columbia, Canada.

PARTICIPANTS

We included 345 individuals ≥12 years of age with a self-reported physician diagnosis of asthma. The diagnosis of asthma was reassessed at the end of 12 months of follow-up using a structured algorithm, which included a bronchodilator reversibility test, methacholine challenge test, and if necessary medication tapering and a second methacholine challenge test.

PRIMARY AND SECONDARY OUTCOME MEASURES

Self-reported annual asthma-related direct healthcare costs (2017 Canadian dollars), outpatient physician visits and medication use from the perspective of the Canadian healthcare system.

RESULTS

Asthma was ruled out in 86 (24.9%) participants. The average annual asthma-related direct healthcare costs for participants with confirmed asthma were $C497.9 (SD $C677.9) and for participants with asthma ruled out, $C307.7 (SD $C424.1). In the adjusted analyses, a confirmed diagnosis was associated with higher direct healthcare costs (relative ratio (RR)=1.60, 95% CI 1.14 to 2.22), increased rate of specialist visits (RR=2.41, 95% CI 1.05 to 5.40) and reliever medication use (RR=1.62, 95% CI 1.09 to 2.35), but not primary care physician visits (p=0.10) or controller medication use (p=0.11).

CONCLUSIONS

A quarter of individuals with a physician diagnosis of asthma did not have asthma after objective re-evaluation. These participants still consumed a significant amount of asthma-related healthcare resources. The population-level economic burden of asthma overdiagnosis could be substantial.

An xQTL map integrates the genetic architecture of the human brain's transcriptome and epigenome

We report a multi-omic resource generated by applying quantitative trait locus (xQTL) analyses to RNA sequence, DNA methylation and histone acetylation data from the dorsolateral prefrontal cortex of 411 older adults who have all three data types. We identify SNPs significantly associated with gene expression, DNA methylation and histone modification levels. Many of these SNPs influence multiple molecular features, and we demonstrate that SNP effects on RNA expression are fully mediated by epigenetic features in 9% of these loci. Further, we illustrate the utility of our new resource, xQTL Serve, by using it to prioritize the cell type(s) most affected by an xQTL. We also reanalyze published genome wide association studies using an xQTL-weighted analysis approach and identify 18 new schizophrenia and 2 new bipolar susceptibility variants, which is more than double the number of loci that can be discovered with a larger blood-based expression eQTL resource.

Reversal of Phenotypic Abnormalities by CRISPR/Cas9-Mediated Gene Correction in Huntington Disease Patient-Derived Induced Pluripotent Stem Cells

Huntington disease (HD) is a dominant neurodegenerative disorder caused by a CAG repeat expansion in HTT. Here we report correction of HD human induced pluripotent stem cells (hiPSCs) using a CRISPR-Cas9 and piggyBac transposon-based approach. We show that both HD and corrected isogenic hiPSCs can be differentiated into excitable, synaptically active forebrain neurons. We further demonstrate that phenotypic abnormalities in HD hiPSC-derived neural cells, including impaired neural rosette formation, increased susceptibility to growth factor withdrawal, and deficits in mitochondrial respiration, are rescued in isogenic controls. Importantly, using genome-wide expression analysis, we show that a number of apparent gene expression differences detected between HD and non-related healthy control lines are absent between HD and corrected lines, suggesting that these differences are likely related to genetic background rather than HD-specific effects. Our study demonstrates correction of HD hiPSCs and associated phenotypic abnormalities, and the importance of isogenic controls for disease modeling using hiPSCs.

Randomised clinical trial: the clinical efficacy and safety of an alginate-antacid (Gaviscon Double Action) versus placebo, for decreasing upper gastrointestinal symptoms in symptomatic gastroesophageal reflux disease (GERD) in China

BACKGROUND

There is a paucity of large-scale studies evaluating the clinical benefit of the Gaviscon Double Action (DA) alginate-antacid formulation for treating gastroesophageal reflux disease (GERD) symptoms.

AIM

Randomised double-blind placebo-controlled parallel-group study to evaluate efficacy and safety of Gaviscon DA in reducing heartburn, regurgitation and dyspepsia symptoms in individuals with mild-to-moderate GERD in China.

METHODS

Participants with symptomatic GERD (n = 1107) were randomised to receive Gaviscon DA or placebo (two tablets four times daily) for seven consecutive days. The primary endpoint compared the change in Reflux Disease Questionnaire (RDQ) score for the GERD (heartburn + regurgitation) dimension between Gaviscon DA and placebo. Secondary endpoints compared the change in RDQ scores for individual heartburn, regurgitation and dyspepsia dimensions, overall treatment evaluation (OTE) scores and incidence of adverse events (AEs).

RESULTS

Mean RDQ GERD scores: 2.51 for Gaviscon DA and 2.50 for placebo at baseline; 1.25 for Gaviscon DA and 1.46 for placebo post treatment. Gaviscon DA was statistically superior to placebo in reducing GERD and dyspepsia RDQ scores [least-squares mean (LSM) difference: GERD -0.21, P < 0.0001; dyspepsia -0.18, P = 0.0004], despite a substantial placebo response. The Gaviscon DA group reported more favourable overall treatment responses than the placebo group across all OTE categories (P < 0.0001). Superior relief of GERD symptoms was observed both in those with non-erosive and those with erosive reflux disease (LSM difference -0.14 [P = 0.038] and -0.29 [P < 0.0001] respectively). Incidence of AEs was similar in both groups.

CONCLUSION

Gaviscon DA tablets provide effective and safe reduction in acid reflux and dyspepsia symptoms in Chinese individuals with mild-to-moderate GERD. ClinicalTrials.gov: NCT01869491.

Hybrid phase-change plasmonic crystals for active tuning of lattice resonances

Tunable lattice resonances are demonstrated in a hybrid plasmonic crystal incorporating the phase-change material Ge2Sb2Te5 (GST) as a 20-nm-thick layer sandwiched between a gold nanodisk array and a quartz substrate. Non-volatile tuning of lattice resonances over a range Δλ of about 500 nm (1.89 µm to 2.27 µm) is achieved experimentally via intermediate phase states of the GST layer. This work demonstrates the efficacy and ease of resonance tuning via GST in the near infrared, suggesting the possibility to design broadband non-volatile tunable devices for optical modulation, switching, sensing and nonlinear optical devices.

Enhancement of waste activated sludge anaerobic digestion by a novel chemical free acid/alkaline pretreatment using electrolysis

Anaerobic digestion of waste activated sludge (WAS) is relatively poor due to hydrolysis limitations. Acid and alkaline pretreatments are effective in enhancing hydrolysis leading to higher methane yields. However, chemical costs often prohibit full-scale application. In this study, 12 V two-chamber electrolysis using an anion exchange membrane alters sludge pH without chemical dosing. pH dropped from 6.9 to 2.5 in the anode chamber and increased to 10.1 in the cathode chamber within 15 h. The volatile suspended solids solubilisation of WAS was 31.1% in the anode chamber and 34.0% in the cathode chamber. As a result, dissolved chemical oxygen demand increased from 164 to 1,787 mg/L and 1,256 mg/L in the anode and cathode chambers, respectively. Remixing of sludge from the two chambers brought the pH back to 6.5, hence no chemical neutralisation was required prior to anaerobic digestion. Methane yield during anaerobic digestion at 20 d retention time was 31% higher than that of untreated sludge. An energy balance assessment indicated that the non-optimised process could approximately recover the energy (electricity) expended in the electrolysis process. With suitable optimisation of treatment time and voltages, significant energy savings would be expected in addition to the benefit of decreased sludge volume.

The effect of pressure pad location of spinal orthosis on the treatment of adolescent idiopathic scoliosis (AIS)

Patient with moderate AIS is usually prescribed with spinal orthosis aiming to mechanically support and prevent the spine from further deterioration. In the conventional fitting method, pre-brace X-ray is the main reference, thus, the pressure pad of spinal orthosis may not be accurately located to the strategic areas because the spinal deformities could change 3-dimensionally once pressure pad is applied. A high correlation (r > 0.98) between Cobb's angle and spinous process angle (SPA) was found in the recent studies. With the advancements of 3D clinical ultrasound (3D CUS), tracing SPA along a scoliotic spine becomes possible and this can be used to estimate Cobb's angle. This study aimed to evaluate the effect of pressure pad location of spinal orthosis in the treatment of AIS and 3D CUS was used to trace SPA for estimation of Cobb's angle. The in-brace X-rays were assessed for confirmation of treatment effectiveness. The subjects were divided into ultrasound-guided fitting group A (n=21) and conventional fitting group B (n=22). In the group A, pressure pads were tested at 5 locations - the prescribed location as in the conventional fitting (referred to the pre-brace X-ray), and 1 cm and 2 cm above and below the prescribed location, and 3D CUS was applied to trace the SPA in these 5 pad locations, and the pad location with the lowest estimated Cobb's angle was selected in the final fitting. The assessments of in-brace X-rays showed that the mean Cobb's angle of group A decreased from 28.9° (pre-brace) to 18.6° (immediate in-brace) while the mean Cobb's angle of group B decreased from 27.1° (pre-brace) to 22.5° (immediate in-brace). There was a significant difference (p < 0.05) in the correction of Cobb's angle between the two groups. The results showed that accurate pressure pad location does play an important role in the reduction of Cobb's angle and 3D CUS can be considered as a non-invasive and effective assessment tool to improve orthotic treatment of AIS.

Lattice resonances in antenna arrays for liquid sensing in the terahertz regime

Terahertz antenna arrays supporting narrow lattice resonances are proposed as an alternative sensor-on-chip approach to liquid sensing. An array of metallic rectangular antennas fabricated on a polyethylene naphthalate (PEN) substrate is used to demonstrate the sensing of a number of fluids. Good agreement is shown between experiment and simulation with Q-factors of around 20 and a figure-of-merit (FOM) of 3.80 being achieved. Liquid sensing with antenna arrays is simple both in terms of fabrication and setup. The working frequency can be tuned with a suitable choice of substrates and array parameters. The nature of the lattice resonance means that the whole sample is used to provide the conditions required for resonance occurrence, eliminating the need to preferentially locate the sample in small areas of high field concentration. The antenna arrays could also potentially be coupled with a microfluidic system for in situ sensing or used in a reflection setup.

Broadband multi-layer terahertz metamaterials fabrication and characterization on flexible substrates

Microscopic split-ring-resonator (SRR) arrays are fabricated on 100 μm thick polyethylene naphthalate (PEN) films by femtosecond laser micro-lens array (MLA) lithography. The transmission properties of these metamaterials are characterized by THz Time Domain Spectroscopy (THz-TDS). Tunable resonance responses can be achieved by changing SRR structural design parameters. By stacking 2D PEN metamaterial films with different frequency responses together, a broadband THz filter with full width at half maximum (FWHM) of 0.38 THz is constructed. The bandwidth of the resonance response increases up to 4.2 times as compared to the bandwidths of single layer metamaterials. Numerical simulation reveals that SRR layers inside the multi-layer metamaterials are selectively excited towards specific frequencies within the broadband response. Meanwhile, more than one SRR layers respond to the chosen frequencies, resulting in the enhancement of the resonance properties. The multi-layer metamaterials provide a promising way to extend SRR based metamaterial operating region from narrowband to broadband with a tunable feature.

Generation of pronounced Fano resonances and tuning of subwavelength spatial light distribution in plasmonic pentamers

Arrays of plasmonic pentamers consisting of five metallic nano-disks were designed and fabricated to achieve a pronounced Fano Resonance with polarization-independent far-field spectral response at normal incidence due to the structure symmetry of pentamers. A mass-spring coupled oscillator model was applied to study plasmon interactions among the nano-disks. It was found that the direction of the excitation light polarization can flexibly tune the spatial localization of near-field energy at sub-wavelength scales while the collective optical properties are kept constant. It can lead to a selective storage of excited energy down to sub-20 nm gap at a normal incident with a single light source.

Innovative practice. applying academic psychosmatic medicine in rural California

Background

Imperial County is designated as medically underserved and one of the poorest counties in CA. Our practice started in 1994 and serves the gap between the County Mental Health Services (CMHS) that treats the severely and chronically ill and the general medical community that faces the unmet need of specialty care for “less” severe patients.

Methods

A plan was started to provide both psychiatric care and liaison activities. The community has 2 community general hospitals. Contracts were established with CMHS and private insurers to assure coverage of services. The plan was extended to dialysis units and long term facilities. Systematic collection of consult data was started in 1998.

An electronic medical record was established with specific fields designated for research purposes. Working in association with UCSD, we established a number of IRB approved protocols. In addition, we contracted with a number of pharmaceutical companies to become a research site for mult-center trials.

Results

Over 300 consultations were performed yearly. The most common consultations involved assessments of: elderly agitated patients, conservatorship evaluations and suicide attempts.

Conclusion

PM strategies added value in the provision of psychiatric services and contract negotiation in this rural community. Applying an academic model decreased the gap between CMHS and the medical community. Patients appeared satisfied to see the same psychiatrists at different treatment settings (i.e. general hospital, dialysis unit, NSF). All interventions were covered by the diverse payment sources.

Application of 3-D ultrasound in assisting the fitting procedure of spinal orthosis to patients with adolescent idiopathic scoliosis

Spinal orthosis is generally applied to the patients with adolescent idiopathic scoliosis (AIS) during puberty to mechanically support the spine and prevent further deterioration. However, the optimum location of pressure is not easy to be determined and the X-ray taken is not a real time presentation of the spinal curvature. With the advancement of clinical ultrasound, tracing spinal processes along a scoliotic spine becomes possible, which means spinous process angle (SPA) can be obtained from ultrasound images. Moreover, SPA is found to be highly correlated with Cobb's angle. Since the outcome of orthotic intervention for AIS is considered to be associated with accurate orthosis fitting, this study seeks to apply three-dimensional (3-D) ultrasound in the fitting procedure of spinal orthosis for patients with AIS. The accuracy of pressure pad location in brace can help to improve the effectiveness of spinal orthosis treatment. By means of the ultrasound assessments, spinous process angle is examined and used as the parameter to evaluate the optimal location for pressure pad. The intra-rater reliability [ICC (1, 3)] for using ultrasound to measure SPA is >0.9 (p<0.05). Furthermore, the correlation between Cobb's angle estimated from the measurement of SPA in 3-D ultrasound images and Cobb's angle measured from X-ray is highly significant (R=0.98, p<0.01). According to these findings, ultrasound can be further developed as a non-invasive real-time assessment tool for spinal curvature especially in fitting stage to improve the treatment effect of the spinal orthosis.

Chromosome translocations and fusion genes in breast cancer

Abstract #2021

Background: Little is known about chromosome translocations in the common epithelial cancers such as breast cancer, in spite of the central role played by translocations and consequent gene fusions in haematopoietic cancers.&#x2028; Methods: We present a comprehensive analysis by array painting of the chromosome translocations of four breast cancer cell lines, DU4475, HCC1806, HCC1187 and ZR-75-30. In array painting chromosomes are isolated by flow cytometry, amplified and hybridized to DNA microarrays. All breakpoints, totalling nearly 250, were mapped to at least 1Mb resolution and most balanced breakpoints were mapped to about 2kb resolution using custom oligonucleotide arrays. The remaining unbalanced breakpoints were mapped to around 20kb by identifying copy number steps in Affymetrix SNP6 array hybrizations obtained by the Sanger Institute's Cancer Genome Project. Breast tumours in parraffin section in tissue microarrays were screened by FISH to see whether selected breakpoints found in the cell lines are present in breast tumours.&#x2028; Results: We found at least 12 reciprocal translocations in the four cell lines, substantially more than expected, and many more rearrangements were balanced for at least one participating chromosome. Many of the breakpoints were within or adjacent to cancer-relevant genes, and three of the translocations have already been shown to form fusion transcripts, RIF1-PKD1L1, PUM1-TRERF1 and TAX1BP1-AHCY. For selected genes targetted by the translocations, about 100 breast tumours were screened for breaks. Breaks were found in two to six cases for several of the genes, confirming that some of them were broken in breast tumours. For example two cases of unbalanced breakage were identified in PKD1L1, and these were confirmed by array-CGH.&#x2028; Discussion: Our results suggest that breast cancers have fusion genes, and support the emerging view that chromosome rearrangements are likely to play a significant role in common epithelial cancers.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2021.

Herniation of caecum through the foramen of Winslow

The radiological features on plain abdominal imaging and CT in a case of caecal herniation through the foramen of Winslow is presented. This rare condition is associated with a high morbidity and mortality, which emphasizes the importance of accurate preoperative diagnosis.

Shedding of distinct cryptic epitope (HU177) in sera of melanoma patients

8550

Background: Our preclinical data suggest that a newly identified cryptic epitope HU177 within collagen regulates endothelial and tumor cell adhesion in-vitro and angiogenesis and tumor growth in-vivo. We investigated whether 1) HU177 shedding can be measured in melanoma patients’ sera, and 2) if HU177 concentration correlates with clinicopathological features, recurrence and survival. Methods: Sera from 291 melanoma patients (primary Stage I, n=140; II n=41; III n=29; recurrent/metastatic n=81) and 30 normal volunteers prospectively enrolled at the NYU School of Medicine were analyzed for HU177 epitope concentration (ng/ml) by ELISA. Microtiter plates were incubated overnight with monoclonal antibody (anti-HU177 epitope). Patients’ sera and standards (denatured type-IV collagen) were added in duplicate followed by dilutions of biotinylated anti-collagen type IV polyclonal and HRP-labeled anti-biotin antibodies with multiple washes after each incubation. Absorbance was monitored at 400 nm. Results: The mean concentration of anti-HU177 epitope was 5.8 ng/ml (range 0.1 to 139.8). Normal volunteers were 1.6±0.3 (mean ± SEM). A significant correlation was observed between HU177 concentration and tumor thickness in patients who presented with primary melanoma (=1.00 mm, n=113, 3.8±0.4; 1.01–3.99 mm, n=72, 8.9 ±2.1; =4.00 mm, n=22, 10.3±2.2; P=0.003 by ANOVA test) and nodular melanoma histological subtype (nodular, n=47, 10.5±3.1; superficial spreading, n=95, 4.4±0.5; others, n=68, 6.0±2.1; P=0.02, ANOVA). Multivariate analysis confirmed the independent correlation between higher HU177 concentration and nodular subtype after controlling for tumor thickness (P=0.04). Primary patients with ulcerated melanomas and those who developed recurrences both showed higher HU177 epitope levels, however, the difference was not significant (P>0.05). Conclusions: This is the first study on HU177 epitope shedding in melanoma patients. Data demonstrate the clinical feasibility of HU177 testing in melanoma patients’ sera and suggest that HU177 epitope shedding correlates with thicker primary melanomas. Longer follow-up is required to better define the prognostic value of HU177 epitope shedding in melanoma patients.

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Modulation of prostacyclin and thromboxane secretion by cytotrophoblasts from normal and pre-eclamptic human pregnancies

We and others have previously observed an imbalance in cytotrophoblast secretion of the vasoactive prostanoids prostacyclin and thromboxane A(2) in pre-eclampsia. To examine the effects of potential modulators of this imbalance, cytotrophoblasts isolated from normal and pre-eclamptic pregnancies were incubated in the presence of lipopolysaccharide, the calcium ionophore A23187, tumour necrosis factor alpha, or interleukin 1beta, with or without the cyclo-oxygenase inhibitor, indomethacin. Further incubations included the drugs tranylcypromine, a prostacyclin synthetase inhibitor (0.1, 10 microM ), or the thromboxane synthetase inhibitor, pirmagrel (0.001, 1 microM ). Results showed that cytotrophoblasts from pre-eclamptic pregnancies had increased thromboxane production and significant stimulation of prostacyclin production by lipopolysaccharide and calcium ionophore. Lipopolysaccharide stimulated thromboxane production in normal cytotrophoblasts, while indomethacin almost completely inhibited production of both prostanoids. Tranylcypromine mildly inhibited prostacyclin production in normal cytotrophoblasts only, whereas pirmagrel strongly inhibited thromboxane production in a dose-related manner, with reciprocal increase in prostacyclin production occurring in cytotrophoblasts from pre-eclamptic pregnancies. This study confirmed that cytotrophoblasts from pre-eclamptic women had increased thromboxane production and showed that pirmagrel, at the relatively low dose of 0.001 microM, was able to normalize the imbalance of thromboxane and prostacylin production and may therefore warrant further investigation as a treatment for pre-eclampsia.

Poliovirus 3C protease-mediated degradation of transcriptional activator p53 requires a cellular activity

Infection of HeLa cells with poliovirus leads to rapid shut-off of host cell transcription by RNA polymerase II. Previous results have suggested that both the basal transcription factor TBP (TATA-binding protein) and transcription activator proteins such as CREB (cyclic AMP-responsive element-binding protein) and Oct-1 (the octamer-binding factor) are cleaved by the viral-encoded protease, 3C(Pro). Here we demonstrate that the transcriptional activator (and tumor suppressor) p53 is degraded by the viral protease 3C both in vivo and in vitro. Unlike other transcription factors that are directly cleaved by 3C(pro), degradation of p53 requires a HeLa cell activity in addition to 3C(Pro). The degradation of p53 by 3C(Pro) does not appear to involve the ubiquitin pathway of protein degradation. Vaccinia virus infection of HeLa cells leads to inactivation of the cellular activity required for 3C(Pro)-mediated degradation of p53. The vaccinia-encoded protein (CrmA) is known to inhibit caspase I (ICE protease) that converts inactive IL-1beta to an active secreted form. Incubation of HeLa cells with caspase I inhibitor Z-VAD-fmk does not interfere with 3C(Pro)-mediated degradation of p53. The cellular activity present in extracts of HeLa cells can be fractionated through phosphocellulose. A partially purified fraction that elutes at 0.6 M KCl from phosphocellulose contains the activity that degrades p53 in a 3C(Pro)-dependent manner. These results suggest that both poliovirus-encoded protease 3C(Pro) and a cellular activity are required for the degradation of p53 observed in cells infected with poliovirus.

A proapoptotic peptide for the treatment of solid tumors

We have designed a novel peptide, DP1, which is able to mediate significant induction of apoptosis in solid tumors by local injection. This peptide, comprised of a protein transduction domain (PTD), PTD-5, fused to an antimicrobial peptide, (KLAKLAK)2, was able to trigger rapid apoptosis in a variety of cell lines in vitro, including MCA205 murine fibrosarcomas and human head and neck tumors. Furthermore, direct injection of DP1 into day 7 established MCA205 tumors in C57BL/6 mice resulted in the induction of tumor apoptosis and subsequent reduction in tumor volume. These results suggest that DP1 may be used clinically to treat accessible solid tumors or as an adjuvant therapy in conjunction with radiotherapy, standard chemotherapy, immunotherapy, or surgical debulking.