Navigating job and cancer demands during treatment: A qualitative study of ovarian cancer patients.

OBJECTIVE: Our objective was to obtain perspectives from ovarian cancer patients on job demands, cancer demands, and workplace or cancer resources and strategies to manage the cancer-work interface using the cancer-work management conceptual framework. METHODS: We recruited ovarian cancer patients receiving systemic therapy who screened positive for financial distress using Comprehensive Score for Financial Toxicity <26. Interviews were conducted with participants about their costs of care, including employment concerns. Interviews were recorded, transcribed verbatim, and analyzed by three researchers using an inductive thematic analysis. RESULTS: Of 22 participants, the average age was 57 years old, 36% were Black, 68% had income <$40,000, 41% had public insurance, and 68% were being treated for recurrent disease. Job demands included decreased productivity, inability to return to work, and worry about losing a job or employer-based health insurance coverage. Cancer demands included physical and cognitive limitations due to cancer treatment and reliance on caregivers, especially for transportation. Workplace resources/strategies including having a supportive employer, modifying job responsibilities, and utilizing family medical leave. Cancer care resources/strategies included planning appointments ahead of time and utilizing resources, such as disability. CONCLUSIONS: Cancer care teams should consider screening patients for employment concerns; streamline care to minimize the side effects, time, and transportation demands of treatment on patients and caregivers; maximize utilization of available resources; and proactively communicate with employers to accommodate patients and caregivers who want or need to work.

Multi-center bonds as resonance hybrids: A real space perspective.

The concept of distinct bonds within molecules has proven to be successful in rationalizing chemical reactivity. However, bonds are not a well-defined physical concept, but rather vague entities, described by different and often contradicting models. With probability density analysis, which can-in principle-be applied to any wave function, bonds are recovered as spin-coupled positions within most likely electron arrangements in coordinate space. While the wave functions of many systems are dominated by a single electron arrangement that is built from two-center two-electron bonds, some systems require several different arrangements to be well described. In this work, a range of these multi-center bonded molecules are classified and investigated with probability density analysis. The results are compared with valence bond theory calculations and data from collision-induced dissociation experiments.

Modulating medial prefrontal cortex activity using real-time fMRI neurofeedback: Effects on reality monitoring performance and associated functional connectivity.

Neuroimaging studies have found 'reality monitoring', our ability to distinguish internally generated experiences from those derived from the external world, to be associated with activity in the medial prefrontal cortex (mPFC) of the brain. Here we probe the functional underpinning of this ability using real-time fMRI neurofeedback to investigate the involvement of mPFC in recollection of the source of self-generated information. Thirty-nine healthy individuals underwent neurofeedback training in a between groups study receiving either Active feedback derived from the paracingulate region of the mPFC (21 subjects) or Sham feedback based on a similar level of randomised signal (18 subjects). Compared to those in the Sham group, participants receiving Active signal showed increased mPFC activity over the course of three real-time neurofeedback training runs undertaken in a single scanning session. Analysis of resting state functional connectivity associated with changes in reality monitoring accuracy following Active neurofeedback revealed increased connectivity between dorsolateral frontal regions of the fronto-parietal network (FPN) and the mPFC region of the default mode network (DMN), together with reduced connectivity within ventral regions of the FPN itself. However, only a trend effect was observed in the interaction of the recollection of the source of Imagined information compared with recognition memory between participants receiving Active and Sham neurofeedback, pre- and post- scanning. As such, these findings demonstrate that neurofeedback can be used to modulate mPFC activity and increase cooperation between the FPN and DMN, but the effects on reality monitoring performance are less clear.

De-escalation of axillary surgery in breast cancer patients treated in the neoadjuvant setting: a Dutch population-based study.

PURPOSE: An overall trend is observed towards de-escalation of axillary surgery in patients with breast cancer. The objective of this study was to evaluate this trend in patients treated with neoadjuvant systemic therapy (NST). METHODS: Patients with cT1-4N0-3 breast cancer treated with NST (2006-2016) were selected from the Netherlands Cancer Registry. Patients were classified by clinical node status (cN) and type of axillary surgery. Uni- and multivariable logistic regression analyses were performed to determine the clinicopathological factors associated with performing ALND in cN+ patients. RESULTS: A total of 12,461 patients treated with NST were identified [5830 cN0 patients (46.8%), 6631 cN+ patients (53.2%)]. In cN0 patients, an overall increase in sentinel lymph node biopsy (SLNB) only (not followed by ALND) was seen from 11% in 2006 to 94% in 2016 (p < 0.001). SLNB performed post-NST increased from 33 to 62% (p < 0.001). In cN+ patients, an overall decrease in ALND was seen from 99% in 2006 to 53% in 2016 (p < 0.001). Age (OR 1.01, CI 1.00-1.02), year of diagnosis (OR 0.47, CI 0.44-0.50), HER2-positive disease (OR 0.62, CI 0.52-0.75), clinical tumor stage (T2 vs. T1 OR 1.32, CI 1.06-1.65, T3 vs. T1 OR 2.04, CI 1.58-2.63, T4 vs. T1 OR 6.37, CI 4.26-9.50), and clinical nodal stage (N3 vs. N1 OR 1.65, CI 1.28-2.12) were correlated with performing ALND in cN+ patients. CONCLUSIONS: ALND decreased substantially over the past decade in patients treated with NST. Assessment of long-term prognosis of patients in whom ALND is omitted after NST is urgently needed.

Novel defect in phosphatidylinositol 4-kinase type 2-alpha (PI4K2A) at the membrane-enzyme interface is associated with metabolic cutis laxa.

Inherited cutis laxa, or inelastic, sagging skin is a genetic condition of premature and generalised connective tissue ageing, affecting various elastic components of the extracellular matrix. Several cutis laxa syndromes are inborn errors of metabolism and lead to severe neurological symptoms. In a patient with cutis laxa, a choreoathetoid movement disorder, dysmorphic features and intellectual disability we performed exome sequencing to elucidate the underlying genetic defect. We identified the amino acid substitution R275W in phosphatidylinositol 4-kinase type IIα, caused by a homozygous missense mutation in the PI4K2A gene. We used lipidomics, complexome profiling and functional studies to measure phosphatidylinositol 4-phosphate synthesis in the patient and evaluated PI4K2A deficient mice to define a novel metabolic disorder. The R275W residue, located on the surface of the protein, is involved in forming electrostatic interactions with the membrane. The catalytic activity of PI4K2A in patient fibroblasts was severely reduced and lipid mass spectrometry showed that particular acyl-chain pools of PI4P and PI(4,5)P2 were decreased. Phosphoinositide lipids play a major role in intracellular signalling and trafficking and regulate the balance between proliferation and apoptosis. Phosphatidylinositol 4-kinases such as PI4K2A mediate the first step in the main metabolic pathway that generates PI4P, PI(4,5)P2 and PI(3,4,5)P3 . Although neurologic involvement is common, cutis laxa has not been reported previously in metabolic defects affecting signalling. Here we describe a patient with a complex neurological phenotype, premature ageing and a mutation in PI4K2A, illustrating the importance of this enzyme in the generation of inositol lipids with particular acylation characteristics.

Gas phase dynamics, conformational transitions and spectroscopy of charged saccharides: the oxocarbenium ion, protonated anhydrogalactose and protonated methyl galactopyranoside.

Protonated intermediates are postulated to be involved in the rate determining step of many sugar reactions. This paper presents a study of protonated sugar species, isolated in the gas phase, using a combination of infrared multiple photon dissociation (IRMPD) spectroscopy, classical ab initio molecular dynamics (AIMD) and quantum mechanical vibrational self-consistent field (VSCF) calculations. It provides a likely identification of the reactive intermediate oxocarbenium ion structure in a d-galactosyl system as well as the saccharide pyrolysis product anhydrogalactose (that suggests oxocarbenium ion stabilization), along with the spectrum of the protonated parent species: methyl d-galactopyranoside-H+. Its vibrational fingerprint indicates intramolecular proton sharing. Classical AIMD simulations for galactosyl oxocarbenium ions, conducted in the temperature range ∼300-350 K (using B3LYP potentials on-the-fly) reveal efficient transitions on the picosecond timescale. Multiple conformers are likely to exist under the experimental conditions and along with static VSCF calculations, they have facilitated the identification of the individual structural motifs of the galactosyl oxocarbenium ion and protonated anhydrogalactose ion conformers that contribute to the observed experimental spectra. These results demonstrate the power of experimental IRMPD spectroscopy combined with dynamics simulations and with computational spectroscopy at the anharmonic level to unravel conformer structures of protonated saccharides, and to provide information on their lifetimes.

Systemic Exosomal Delivery of shRNA Minicircles Prevents Parkinsonian Pathology.

The development of new therapies to slow down or halt the progression of Parkinson's disease is a health care priority. A key pathological feature is the presence of alpha-synuclein aggregates, and there is increasing evidence that alpha-synuclein propagation plays a central role in disease progression. Consequently, the downregulation of alpha-synuclein is a potential therapeutic target. As a chronic disease, the ideal treatment will be minimally invasive and effective in the long-term. Knockdown of gene expression has clear potential, and siRNAs specific to alpha-synuclein have been designed; however, the efficacy of siRNA treatment is limited by its short-term efficacy. To combat this, we designed shRNA minicircles (shRNA-MCs), with the potential for prolonged effectiveness, and used RVG-exosomes as the vehicle for specific delivery into the brain. We optimized this system using transgenic mice expressing GFP and demonstrated its ability to downregulate GFP protein expression in the brain for up to 6 weeks. RVG-exosomes were used to deliver anti-alpha-synuclein shRNA-MC therapy to the alpha-synuclein preformed-fibril-induced model of parkinsonism. This therapy decreased alpha-synuclein aggregation, reduced the loss of dopaminergic neurons, and improved the clinical symptoms. Our results confirm the therapeutic potential of shRNA-MCs delivered by RVG-exosomes for long-term treatment of neurodegenerative diseases.

Working memory moderates the association between condom use intentions and behavior among moderate-to-heavy drinking men who have sex with men.

Men who have sex with men (MSM) are a high-risk population for HIV infection and this risk is increased for those who consume alcohol. Condomless anal intercourse (CAI) is the central transmission risk factor for this population. This study examined whether individual differences in working memory moderated the association between intentions to use condoms and the frequency of CAI among MSM who engaged in anal intercourse over a subsequent 6-week period. Moderate- and heavy-drinking MSM (n = 207) completed questionnaires regarding alcohol use and condom use intentions and an operation span task to assess working memory at baseline. Participants then completed 6 weeks of morning surveys via a mobile phone app to assess anal intercourse frequency with and without condoms. Negative binomial regression analyses showed that the association between intentions to use condoms and episodes of CAI during the monitoring period was moderated by working memory such that intentions predicted CAI for those high in working memory but not those low in working memory. These results support the view that self-reported intentions may be less-likely to translate into health behaviors among those with poorer executive functioning skills.

Excision of both pretreatment marked positive nodes and sentinel nodes improves axillary staging after neoadjuvant systemic therapy in breast cancer.

BACKGROUND: Marking the axilla with radioactive iodine seed and sentinel lymph node (SLN) biopsy have been proposed for axillary staging after neoadjuvant systemic therapy in clinically node-positive breast cancer. This study evaluated the identification rate and detection of residual disease with combined excision of pretreatment-positive marked lymph nodes (MLNs) together with SLNs. METHODS: This was a multicentre retrospective analysis of patients with clinically node-positive breast cancer undergoing neoadjuvant systemic therapy and the combination procedure (with or without axillary lymph node dissection). The identification rate and detection of axillary residual disease were calculated for the combination procedure, and for MLNs and SLNs separately. RESULTS: At least one MLN and/or SLN(s) were identified by the combination procedure in 138 of 139 patients (identification rate 99·3 per cent). The identification rate was 92·8 per cent for MLNs alone and 87·8 per cent for SLNs alone. In 88 of 139 patients (63·3 per cent) residual axillary disease was detected by the combination procedure. Residual disease was shown only in the MLN in 20 of 88 patients (23 per cent) and only in the SLN in ten of 88 (11 per cent), whereas both the MLN and SLN contained residual disease in the remainder (58 of 88, 66 per cent). CONCLUSION: Excision of the pretreatment-positive MLN together with SLNs after neoadjuvant systemic therapy in patients with clinically node-positive disease resulted in a higher identification rate and improved detection of residual axillary disease.

ANTECEDENTES: En el cáncer de mama con ganglios positivos clínicamente tras el tratamiento neoadyuvante sistémico, se ha propuesto la utilización de iodo radioactivo (Marking Axilla with Radioactive Iodine, MARI) y de la biopsia de ganglio linfático centinela para la estadificación axilar. En este estudio se evaluó la tasa de identificación y detección de enfermedad residual cuando se combinó la exéresis de los ganglios linfáticos marcados antes del tratamiento (marked lymph nodes, MLN) junto con los ganglios centinela (sentinel lymph nodes, SLN). MÉTODOS: Se realizó un análisis retrospectivo multicéntrico de pacientes con cáncer de mama con ganglios positivos clínicamente que se sometieron a tratamiento neoadyuvante sistémico y en las que se combinaron ambas técnicas (con o sin disección axilar). Se calcularon las tasas de identificación y detección de enfermedad residual axilar para MLN y SLN por separado y en conjunto. RESULTADOS: En 138/139 pacientes se identificaron ≥ 1 MLN y/o SLN combinando ambas técnicas (tasa de identificación del 99,3%). La tasa de identificación fue de 92,8% para MLN y del 87,8% para SLN. Combinando ambas técnicas se detectó enfermedad axilar residual en 88/139 (63,3%) pacientes. Se detectó enfermedad residual en 20/88 (22,7%) pacientes utilizando únicamente MLN, en 10/88 (11,4%) pacientes utilizando únicamente SLN y en 58/88 (65,9%) combinando ambas técnicas. CONCLUSIÓN: La exéresis conjunta de los ganglios marcados con iodo radioactivo antes del tratamiento neoadyuvante sistémico y de los ganglios centinela después del tratamiento en pacientes con cN+ logró una tasa de identificación más alta y una mejor detección de la enfermedad axilar residual.

Type II PI4-kinases control Weibel-Palade body biogenesis and von Willebrand factor structure in human endothelial cells.

Weibel-Palade bodies (WPBs) are endothelial storage organelles that mediate the release of molecules involved in thrombosis, inflammation and angiogenesis, including the pro-thrombotic glycoprotein von Willebrand factor (VWF). Although many protein components required for WPB formation and function have been identified, the role of lipids is almost unknown. We examined two key phosphatidylinositol kinases that control phosphatidylinositol 4-phosphate levels at the trans-Golgi network, the site of WPB biogenesis. RNA interference of the type II phosphatidylinositol 4-kinases PI4KIIα and PI4KIIß in primary human endothelial cells leads to formation of an increased proportion of short WPB with perturbed packing of VWF, as exemplified by increased exposure of antibody-binding sites. When stimulated with histamine, these cells release normal levels of VWF yet, under flow, form very few platelet-catching VWF strings. In PI4KIIα-deficient mice, immuno-microscopy revealed that VWF packaging is also perturbed and these mice exhibit increased blood loss after tail cut compared to controls. This is the first demonstration that lipid kinases can control the biosynthesis of VWF and the formation of WPBs that are capable of full haemostatic function.

Cytomorphology and sonographic features of ectopic thymic tissue diagnosed in paediatric FNA biopsies.

INTRODUCTION: Ectopic thymic tissue can arise as an asymptomatic neck mass, which may be detected on imaging studies. The aim of this study was to determine the incidence of ectopic thymic tissue in paediatric FNAs and to the correlate clinical, radiological and cytomorphological findings. METHODS: FNAs in children with neck and mediastinal lesions performed between January 2012 and July 2016 were reviewed for cases of ectopic thymus. These were then evaluated and correlated with the cytology findings. RESULTS: Of 739 FNAs, 13 (1.8%) cases from 11 patients showed ectopic thymic tissue. The targeted lesions were in the thyroid (n = 7), submandibular region (n = 1), superior mediastinum (n = 1) and paratracheal region (n = 1). The most common indication was for microcalcifications concerning for papillary thyroid carcinoma on ultrasound (n = 6). Imaging findings included fusiform lesions with linear and punctuate bright echoes. The cytology evaluation showed small lymphocytes with discohesive epithelioid cells in most cases, and proteinaceous fluid in the cystic case. There were rare macrophages and Hassall's corpuscles. Flow cytometry and/or immunostains were performed in all cases, supporting thymic origin. CONCLUSION: Ectopic thymic tissue is rarely present as a neck mass or thyroid nodule on FNA biopsy. The ultrasound imaging findings reveal a well-defined fusiform lesion with punctate bright echoes that could be misinterpreted as papillary thyroid carcinoma. The aspirates show a small lymphoid population, immunophenotypically compatible with thymic T-cells, in addition to scattered epithelial cells. Therefore, knowledge of the typical ultrasonographic and cytopathological features can help make a definitive diagnosis and avoid more invasive procedures in paediatric patients.

Spanish version validation of the Marihuana Motives Measure in a drug-consuming adolescent sample. / Propiedades psicométricas de la versión española del Marihuana Motives Measure en población adolescente consumidora.

INTRODUCTION: Cannabis is the illicit drug mostly widely consumed by adolescents in Spain. The understanding of consumption motives is an important factor for intervention. In Spain, there are no available instruments for their evaluation, hence, the goal of this paper is to study the psychometric properties of the Marihuana Motives Measure (MMM) in a sample of adolescent consumers. MATERIAL AND METHOD: Firstly, translation and back-translation was performed. A total of 228 adolescent consumers of cannabis were evaluated. Factorial analysis was conducted, and the reliability of the total scores and of each scale of the questionnaire was studied through Cronbach's alpha. Test-retest reliability was analyzed through interclass correlations. Validity evidence of the MMM was examined through correlations between current cannabis use, subjective consumption effects measured with the Addiction Research Center Inventory (ARCI), and personality measured with the Millon Adolescent Clinical Inventory (MACI). RESULTS: High reliability was observed in total score of the MMM (Cronbach α = .86), and high and moderate reliability for each of the five factors obtained in the factorial analysis of the MMM, Social = .82, Enhancement = .72, Coping = .83, Expansion = .74, and Conformity = .64. Significant correlations were also observed between cannabis consumption motives and subjective effects, and between consumption motives and personality. CONCLUSION: The Spanish version of the MMM shows a similar factorial structure as the one obtained by the original author, and its measures are reliable and valid for the study of cannabis consumption motives in adolescent consumer population.

Introducción: El cannabis es la sustancia ilegal que más consumen los adolescentes españoles. Entender los motivos de consumo es un factor importante para la intervención. Actualmente no existe en España un instrumento para su evaluación. El objetivo del presente trabajo es estudiar las propiedades psicométricas de la versión española del cuestionario Marihuana Motives Measure (MMM) en una población de adolescentes consumidores. Material y Métodos: Se llevó a cabo una traducción y retrotraducción del MMM. Un total de 228 adolescentes consumidores de cánnabis fueron evaluados. Se realizó un análisis factorial y se estudió la fiabilidad de la puntuación total y de cada una de las escalas del cuestionario a partir del Alfa de Cronbach. El estudio de la evidencia de validez del MMM se realizó mediante el examen de las correlaciones entre el uso actual de cánnabis, los efectos subjetivos del consumo través del cuestionario ARCI (Addiction Research Center Inventory) y la personalidad, mediante el cuestionario MACI (Millon Adolescent Clinical Inventory). Resultados: Se observó una alta fiabilidad de la puntuación total del MMM (Alfa de Cronbach= 0,86) y entre alta y moderada para cada uno de los cinco factores obtenidos al realizar el análisis factorial del MMM, Social = 0,82; Enhancement = 0,72; Coping = 0,83; Expansion = 0,74; Conformity = 0,64. Además, se observaron correlaciones significativas tanto entre motivos de consumo de cannabis y efectos subjetivos, así como entre motivos de consumo y personalidad. Conclusiones: La versión española del MMM muestra una estructura factorial similar a la obtenida por el autor original y sus medidas resultan fiables y válidas para el estudio de los motivos de consumo de cánnabis en población adolescente consumidora.

Prognosis of residual axillary disease after neoadjuvant chemotherapy in clinically node-positive breast cancer patients: isolated tumor cells and micrometastases carry a better prognosis than macrometastases.

PURPOSE: The aim of this study was to compare disease-free survival (DFS) and overall survival (OS) between clinically node-positive breast cancer patients, treated with neoadjuvant chemotherapy (NAC), with axillary pathologic complete response (ypN0), residual axillary isolated tumor cells or micrometastases (ypNitc/mi), and residual axillary macrometastases (ypN1-3). METHODS: All patients diagnosed with clinically node-positive primary invasive breast cancer treated with NAC and subsequent axillary lymph node dissection between 2005 and 2008 were retrospectively analyzed. Data were obtained from the Netherlands Cancer Registry. Patients were stratified by final pathological axillary status: ypN0, ypNitc/mi, or ypN1-3. The main outcome measures DFS and OS were analyzed using Kaplan-Meier survival analysis. Uni- and multivariable cox regression analyses were used to determine independent predictors for DFS and OS. RESULTS: A total of 1347 patients were included. Pathologic nodal status was ypN0 in 22.2%, ypNitc/mi in 3.8%, and ypN1-3 in 74.0% of patients. Overall, 5-year DFS was 57.8% and mean OS was 7.4 years. DFS and OS were comparable between ypN0 and ypNitc/mi (HR 1.38 (0.40-4.79, p = 0.613) and HR 0.92 (0.27-3.09, p = 0.889), respectively), but significantly different between ypN0 and ypN1-3 (HR 1.78 (1.06-3.00, p = 0.031) and HR 1.70 (1.07-2.71, p = 0.026), respectively). CONCLUSIONS: Clinically node-positive patients, treated with NAC, with axillary nodal status ypN0 or ypNitc/mi carry similar prognosis regarding DFS and OS. Axillary nodal status ypN1-3 is associated with a less favorable prognosis. Future studies should consider ypN0 and ypNitc/mi as one entity.

Systematic review and meta-analysis of the diagnostic accuracy of ductoscopy in patients with pathological nipple discharge.

BACKGROUND: Invasive surgery remains the standard for diagnosis of pathological nipple discharge (PND). Only a minority of patients with nipple discharge and an unsuspicious finding on conventional breast imaging have cancer. Ductoscopy is a minimally invasive alternative for evaluation of PND. This systematic review and meta-analysis was designed to evaluate the diagnostic accuracy of ductoscopy in patients with PND. METHODS: A systematic search of electronic databases for studies addressing ductoscopy in patients with PND was conducted. Two classification systems were assessed. For DSany , all visualized ductoscopic abnormalities were classified as positive, whereas for DSsusp , only suspicious findings were considered positive. After checking heterogeneity, pooled sensitivity and specificity of DSany and DSsusp were calculated. RESULTS: The search yielded 4642 original citations, of which 20 studies were included in the review. Malignancy rates varied from 0 to 27 per cent. Twelve studies, including 1994 patients, were eligible for meta-analysis. Pooled sensitivity and specificity of DSany were 94 (95 per cent c.i. 88 to 97) per cent and 47 (44 to 49) per cent respectively. Pooled sensitivity and specificity of DSsusp were 50 (36 to 64) and 83 (81 to 86) per cent respectively. Heterogeneity between studies was moderate to large for sensitivity (DSany : I2 = 17·5 per cent; DSsusp : I2 = 37·9 per cent) and very large for specificity (DSany : I2 = 96·8 per cent; DSsusp : I2 = 92·6 per cent). CONCLUSION: Ductoscopy detects about 94 per cent of all underlying malignancies in patients with PND, but does not permit reliable discrimination between malignant and benign findings.

Pathogenetic mechanisms of amyloid A amyloidosis.

Systemic amyloid A (AA) amyloidosis is a serious complication of chronic inflammation. Serum AA protein (SAA), an acute phase plasma protein, is deposited extracellularly as insoluble amyloid fibrils that damage tissue structure and function. Clinical AA amyloidosis is typically preceded by many years of active inflammation before presenting, most commonly with renal involvement. Using dose-dependent, doxycycline-inducible transgenic expression of SAA in mice, we show that AA amyloid deposition can occur independently of inflammation and that the time before amyloid deposition is determined by the circulating SAA concentration. High level SAA expression induced amyloidosis in all mice after a short, slightly variable delay. SAA was rapidly incorporated into amyloid, acutely reducing circulating SAA concentrations by up to 90%. Prolonged modest SAA overexpression occasionally produced amyloidosis after long delays and primed most mice for explosive amyloidosis when SAA production subsequently increased. Endogenous priming and bulk amyloid deposition are thus separable events, each sensitive to plasma SAA concentration. Amyloid deposits slowly regressed with restoration of normal SAA production after doxycycline withdrawal. Reinduction of SAA overproduction revealed that, following amyloid regression, all mice were primed, especially for rapid glomerular amyloid deposition leading to renal failure, closely resembling the rapid onset of renal failure in clinical AA amyloidosis following acute exacerbation of inflammation. Clinical AA amyloidosis rarely involves the heart, but amyloidotic SAA transgenic mice consistently had minor cardiac amyloid deposits, enabling us to extend to the heart the demonstrable efficacy of our unique antibody therapy for elimination of visceral amyloid.

Class I major histocompatibility complex, the trojan horse for secretion of amyloidogenic ß2-microglobulin.

To form extracellular aggregates, amyloidogenic proteins bypass the intracellular quality control, which normally targets unfolded/aggregated polypeptides. Human D76N ß2-microglobulin (ß2m) variant is the prototype of unstable and amyloidogenic protein that forms abundant extracellular fibrillar deposits. Here we focus on the role of the class I major histocompatibility complex (MHCI) in the intracellular stabilization of D76N ß2m. Using biophysical and structural approaches, we show that the MHCI containing D76N ß2m (MHCI76) displays stability, dissociation patterns, and crystal structure comparable with those of the MHCI with wild type ß2m. Conversely, limited proteolysis experiments show a reduced protease susceptibility for D76N ß2m within the MHCI76 as compared with the free variant, suggesting that the MHCI has a chaperone-like activity in preventing D76N ß2m degradation within the cell. Accordingly, D76N ß2m is normally assembled in the MHCI and circulates as free plasma species in a transgenic mouse model.

Clusterin regulates ß-amyloid toxicity via Dickkopf-1-driven induction of the wnt-PCP-JNK pathway.

Although the mechanism of Aß action in the pathogenesis of Alzheimer's disease (AD) has remained elusive, it is known to increase the expression of the antagonist of canonical wnt signalling, Dickkopf-1 (Dkk1), whereas the silencing of Dkk1 blocks Aß neurotoxicity. We asked if clusterin, known to be regulated by wnt, is part of an Aß/Dkk1 neurotoxic pathway. Knockdown of clusterin in primary neurons reduced Aß toxicity and DKK1 upregulation and, conversely, Aß increased intracellular clusterin and decreased clusterin protein secretion, resulting in the p53-dependent induction of DKK1. To further elucidate how the clusterin-dependent induction of Dkk1 by Aß mediates neurotoxicity, we measured the effects of Aß and Dkk1 protein on whole-genome expression in primary neurons, finding a common pathway suggestive of activation of wnt-planar cell polarity (PCP)-c-Jun N-terminal kinase (JNK) signalling leading to the induction of genes including EGR1 (early growth response-1), NAB2 (Ngfi-A-binding protein-2) and KLF10 (Krüppel-like factor-10) that, when individually silenced, protected against Aß neurotoxicity and/or tau phosphorylation. Neuronal overexpression of Dkk1 in transgenic mice mimicked this Aß-induced pathway and resulted in age-dependent increases in tau phosphorylation in hippocampus and cognitive impairment. Furthermore, we show that this Dkk1/wnt-PCP-JNK pathway is active in an Aß-based mouse model of AD and in AD brain, but not in a tau-based mouse model or in frontotemporal dementia brain. Thus, we have identified a pathway whereby Aß induces a clusterin/p53/Dkk1/wnt-PCP-JNK pathway, which drives the upregulation of several genes that mediate the development of AD-like neuropathologies, thereby providing new mechanistic insights into the action of Aß in neurodegenerative diseases.

C-reactive protein is essential for innate resistance to pneumococcal infection.

No deficiency of human C-reactive protein (CRP), or even structural polymorphism of the protein, has yet been reported so its physiological role is not known. Here we show for the first time that CRP-deficient mice are remarkably susceptible to Streptococcus pneumoniae infection and are protected by reconstitution with isolated pure human CRP, or by anti-pneumococcal antibodies. Autologous mouse CRP is evidently essential for innate resistance to pneumococcal infection before antibodies are produced. Our findings are consistent with the significant association between clinical pneumococcal infection and non-coding human CRP gene polymorphisms which affect CRP expression. Deficiency or loss of function variation in CRP may therefore be lethal at the first early-life encounter with this ubiquitous virulent pathogen, explaining the invariant presence and structure of CRP in human adults.

Systemic exosomal siRNA delivery reduced alpha-synuclein aggregates in brains of transgenic mice.

Alpha-synuclein (α-Syn) aggregates are the main component of Lewy bodies, which are the characteristic pathological feature in Parkinson's disease (PD) brain. Evidence that α-Syn aggregation can be propagated between neurones has led to the suggestion that this mechanism is responsible for the stepwise progression of PD pathology. Decreasing α-Syn expression is predicted to attenuate this process and is thus an attractive approach to delay or halt PD progression. We have used α-Syn small interfering RNA (siRNA) to reduce total and aggregated α-Syn levels in mouse brains. To achieve widespread delivery of siRNAs to the brain we have peripherally injected modified exosomes expressing Ravies virus glycoprotein loaded with siRNA. Normal mice were analyzed 3 or 7 days after injection. To evaluate whether this approach can decrease α-Syn aggregates, we repeated the treatment using transgenic mice expressing the human phosphorylation-mimic S129D α-Syn, which exhibits aggregation. In normal mice we detected significantly reduced α-Syn messenger RNA (mRNA) and protein levels throughout the brain 3 and 7 days after treatment with RVG-exosomes loaded with siRNA to α-Syn. In S129D α-Syn transgenic mice we found a decreased α-Syn mRNA and protein levels throughout the brain 7 days after injection. This resulted in significant reductions in intraneuronal protein aggregates, including in dopaminergic neurones of the substantia nigra. This study highlights the therapeutic potential of RVG-exosome delivery of siRNA to delay and reverse brain α-Syn pathological conditions.