Genome sequence analyses identify novel risk loci for multiple system atrophy

Multiple system atrophy (MSA) is an adult-onset, sporadic synucleinopathy characterized by parkinsonism, cerebellar ataxia, and dysautonomia. The genetic architecture of MSA is poorly understood, and treatments are limited to supportive measures. Here, we performed a comprehensive analysis of whole genome sequence data from 888 European-ancestry MSA cases and 7,128 controls to systematically investigate the genetic underpinnings of this understudied neurodegenerative disease. We identified four significantly associated risk loci using a genome-wide association study approach. Transcriptome-wide association analyses prioritized USP38-DT, KCTD7, and lnc-KCTD7-2 as novel susceptibility genes for MSA within these loci, and single-nucleus RNA sequence analysis found that the associated variants acted as cis-expression quantitative trait loci for multiple genes across neuronal and glial cell types. In conclusion, this study highlights the role of genetic determinants in the pathogenesis of MSA, and the publicly available data from this study represent a valuable resource for investigating synucleinopathies.

Clinical Rating Scales for Urinary Symptoms in Parkinson Disease: Critique and Recommendations

Background

The prevalence of lower urinary tract symptoms (LUTS) is high in Parkinson's disease (PD). These problems negatively affect quality of life and include both storage and voiding problems. The International Parkinson and Movement Disorder Society established a task force to review clinical rating scales/questionnaires for the assessment of urinary symptoms in PD.

Methods

According to prespecified criteria, these scales/questionnaires were classified as "Recommended" or "Recommended with caveats" when clinimetric properties were satisfactory for Recommended status but had not been assessed specifically in PD, "Suggested" or "Listed." These assessments were applied to rate scales as screening tools for the diagnosis of LUTS and for the rating of symptom severity.

Results

Among scales that included LUTS but focused on overall autonomic or non-motor symptoms in PD, no scale reached the clinimetric rigor to be designated as Recommended or Recommended with caveats, but some were Suggested for either diagnostic screening tools or severity measures. Among primary urological scales, most are well validated in urological setting, but none was validated specifically in PD. DAN-PSS (Danish PSS), ICIQ (International Consultation for Incontinence Questionnaire)-MLUTS (Male Lower Urinary Tract Symptoms), OABq, OABq-SF (ICIQ-OABqol), OAB-V8 (as screening tool), and OABSS (OAB Symptom Score) met criteria for Recommended with caveats.

Conclusion

The Task Force does not recommend the development of a new scale. However, all above-mentioned questionnaires need to be studied further and specifically validated in PD.

New insights into orthostatic hypotension in multiple system atrophy: a European multicentre cohort study

OBJECTIVES

Orthostatic hypotension (OH) is a key feature of multiple system atrophy (MSA), a fatal progressive neurodegenerative disorder associated with autonomic failure, parkinsonism and ataxia. This study aims (1) to determine the clinical spectrum of OH in a large European cohort of patients with MSA and (2) to investigate whether a prolonged postural challenge increases the sensitivity to detect OH in MSA.

METHODS

Assessment of OH during a 10 min orthostatic test in 349 patients with MSA from seven centres of the European MSA-Study Group (age: 63.6 ± 8.8 years; disease duration: 4.2 ± 2.6 years). Assessment of a possible relationship between OH and MSA subtype (P with predominant parkinsonism or C with predominant cerebellar ataxia), Unified MSA Rating Scale (UMSARS) scores and drug intake.

RESULTS

187 patients (54%) had moderate (> 20 mm Hg (systolic blood pressure (SBP)) and/or > 10 mm Hg (diastolic blood pressure (DBP)) or severe OH (> 30 mm Hg (SBP) and/or > 15 mm Hg (DBP)) within 3 min and 250 patients (72%) within 10 min. OH magnitude was significantly associated with disease severity (UMSARS I, II and IV), orthostatic symptoms (UMSARS I) and supine hypertension. OH severity was not associated with MSA subtype. Drug intake did not differ according to OH magnitude except for antihypertensive drugs being less frequently, and antihypotensive drugs more frequently, prescribed in severe OH.

CONCLUSIONS

This is the largest study of OH in patients with MSA. Our data suggest that the sensitivity to pick up OH increases substantially by a prolonged 10 min orthostatic challenge. These results will help to improve OH management and the design of future clinical trials.

Supine hypertension in Parkinson's disease and multiple system atrophy

OBJECTIVE

Supine hypertension (SH) is a feature of cardiovascular autonomic failure that often accompanies orthostatic hypotension and may represent a negative prognostic factor in parkinsonian syndromes. Here we investigated the frequency rate as well as the clinical and tilt test correlates of SH in Parkinson's disease (PD) and multiple system atrophy (MSA).

METHODS

197 PD (33 demented) and 78 MSA (24 MSA-Cerebellar, 54 MSA-Parkinsonian) patients who had undergone a tilt test examination were retrospectively included. Clinical-demographic characteristics were collected from clinical records at the time of the tilt test examination.

RESULTS

SH (>140 mmHg systolic, >90 mmHg diastolic) occurred in 34 % of PD patients (n = 66, mild in 71 % of patients, moderate in 27 %, severe in 2 %) and 37 % of MSA ones (n = 29, mild in 55 % of patients, moderate in 17 %, severe in 28 %). No difference was observed in SH frequency between demented versus gender-, age- and disease duration-matched non-demented PD patients, or between patients with the parkinsonian (MSA-P) versus the cerebellar (MSA-C) variant of MSA. In PD, SH was associated with presence of cardiovascular comorbidities (p = 0.002) and greater systolic (p = 0.007) and diastolic (p = 0.002) orthostatic blood pressure fall. Orthostatic hypotension (p = 0.002), and to a lesser degree, lower daily dopaminergic intake (p = 0.01) and use of anti-hypertensive medications (p = 0.04) were associated with SH in MSA.

INTERPRETATION

One-third of PD and MSA patients suffer from mild to severe SH, independently of age, disease duration or stage. In PD, cardiovascular comorbidities significantly contribute to the development of SH, while in MSA, SH appears to reflect cardiovascular autonomic failure.

The natural history of multiple system atrophy: a prospective European cohort study

BACKGROUND

Multiple system atrophy (MSA) is a fatal and still poorly understood degenerative movement disorder that is characterised by autonomic failure, cerebellar ataxia, and parkinsonism in various combinations. Here we present the final analysis of a prospective multicentre study by the European MSA Study Group to investigate the natural history of MSA.

METHODS

Patients with a clinical diagnosis of MSA were recruited and followed up clinically for 2 years. Vital status was ascertained 2 years after study completion. Disease progression was assessed using the unified MSA rating scale (UMSARS), a disease-specific questionnaire that enables the semiquantitative rating of autonomic and motor impairment in patients with MSA. Additional rating methods were applied to grade global disease severity, autonomic symptoms, and quality of life. Survival was calculated using a Kaplan-Meier analysis and predictors were identified in a Cox regression model. Group differences were analysed by parametric tests and non-parametric tests as appropriate. Sample size estimates were calculated using a paired two-group t test.

FINDINGS

141 patients with moderately severe disease fulfilled the consensus criteria for MSA. Mean age at symptom onset was 56·2 (SD 8·4) years. Median survival from symptom onset as determined by Kaplan-Meier analysis was 9·8 years (95% CI 8·1-11·4). The parkinsonian variant of MSA (hazard ratio [HR] 2·08, 95% CI 1·09-3·97; p=0·026) and incomplete bladder emptying (HR 2·10, 1·02-4·30; p=0·044) predicted shorter survival. 24-month progression rates of UMSARS activities of daily living, motor examination, and total scores were 49% (9·4 [SD 5·9]), 74% (12·9 [8·5]), and 57% (21·9 [11·9]), respectively, relative to baseline scores. Autonomic symptom scores progressed throughout the follow-up. Shorter symptom duration at baseline (OR 0·68, 0·5-0·9; p=0·006) and absent levodopa response (OR 3·4, 1·1-10·2; p=0·03) predicted rapid UMSARS progression. Sample size estimation showed that an interventional trial with 258 patients (129 per group) would be able to detect a 30% effect size in 1-year UMSARS motor examination decline rates at 80% power.

INTERPRETATION

Our prospective dataset provides new insights into the evolution of MSA based on a follow-up period that exceeds that of previous studies. It also represents a useful resource for patient counselling and planning of multicentre trials.

Neurogenic orthostatic hypotension: pathophysiology, evaluation, and management

Neurogenic orthostatic hypotension is a distinctive and treatable sign of cardiovascular autonomic dysfunction. It is caused by failure of noradrenergic neurotransmission that is associated with a range of primary or secondary autonomic disorders, including pure autonomic failure, Parkinson’s disease with autonomic failure, multiple system atrophy as well as diabetic and nondiabetic autonomic neuropathies. Neurogenic orthostatic hypotension is commonly accompanied by autonomic dysregulation involving other organ systems such as the bowel and the bladder. In the present review, we provide an overview of the clinical presentation, pathophysiology, epidemiology, evaluation and management of neurogenic orthostatic hypotension focusing on neurodegenerative disorders.

[Atypical Parkinson syndromes--recent advances in diagnosis and therapy]

The term "atypical Parkinson syndromes" usually encompasses the following diseases: multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). The differential diagnosis is still a challenge even for a movement disorders specialist, not least because of the distinct therapeutic approaches and disease prognosis. The aim of this review is to provide an overview of current diagnostic criteria and therapeutic approaches and to cite recent findings from clinical and experimental studies.

The Movement Disorders task force review of dysautonomia rating scales in Parkinson's disease with regard to symptoms of orthostatic hypotension

Orthostatic hypotension is defined as a blood pressure fall of > 20 mm Hg systolic and/or 10 mm Hg diastolic within 3 minutes of an upright position. The Movement Disorders Society commissioned a task force to assess existing clinical rating scales addressing symptoms of orthostatic hypotension in Parkinson's disease. Seven neurologists and a clinimetrician assessed each scale's previous use and critiqued its clinimetric properties. A scale was "recommended" if it had been applied to populations of patients with Parkinson's disease, with data on its use in studies beyond the group that developed the scale, and was found to be clinimetrically valid. A scale was considered "suggested" if it had been applied to Parkinson's disease, but only 1 of the other criteria was applied. A scale was "listed" if it met only 1 criterion. Symptoms of orthostatic hypotension are generally assessed in scales on wider autonomic or nonmotor symptoms. Some scales designed to detect orthostatic hypotension-related symptoms provide information on their severity: the AUTonomic SCale for Outcomes in PArkinson's Disease and the COMPosite Autonomic Symptom Scale met criteria for recommended with some limitations; the Novel Non-Motor Symptoms Scale and the Orthostatic Grading Scale were classified as suggested. The Self-completed Non-Motor Symptoms Questionnaire for Parkinson's Disease was classified as suggested as a tool for screening orthostatic symptoms. However, these and the listed scales need further validation and application before they can be recommended for clinical use in patients with Parkinson's disease.

Excessive daytime sleepiness in multiple system atrophy (SLEEMSA study)

BACKGROUND

Sleep disorders are common in multiple system atrophy (MSA), but the prevalence of excessive daytime sleepiness (EDS) is not well known.

OBJECTIVE

To assess the frequency and associations of EDS in MSA.

DESIGN

Survey of EDS in consecutive patients with MSA and comparison with patients with Parkinson disease (PD) and individuals without known neurologic disease.

SETTING

Twelve tertiary referral centers.

PARTICIPANTS

Eighty-six consecutive patients with MSA; 86 patients with PD matched for age, sex, and Hoehn and Yahr stage; and 86 healthy subject individuals matched for age and sex.

MAIN OUTCOME MEASURES

Epworth Sleepiness Scale (ESS), modified ESS, Sudden Onset of Sleep Scale, Tandberg Sleepiness Scale, Pittsburgh Sleep Quality Index, disease severity, dopaminergic treatment amount, and presence of restless legs syndrome.

RESULTS

Mean (SD) ESS scores were comparable in MSA (7.72 [5.05]) and PD (8.23 [4.62]) but were higher than in healthy subjects (4.52 [2.98]) (P < .001). Excessive daytime sleepiness (ESS score >10) was present in 28% of patients with MSA, 29% of patients with PD, and 2% of healthy subjects (P < .001). In MSA, in contrast to PD, the amount of dopaminergic treatment was not correlated with EDS. Disease severity was weakly correlated with EDS in MSA and PD. Restless legs syndrome occurred in 28% of patients with MSA, 14% of patients with PD, and 7% of healthy subjects (P < .001). Multiple regression analysis (with 95% confidence intervals obtained using nonparametric bootstrapping) showed that sleep-disordered breathing and sleep efficiency predicted EDS in MSA and amount of dopaminergic treatment and presence of restless legs syndrome in PD.

CONCLUSIONS

More than one-quarter of patients with MSA experience EDS, a frequency similar to that encountered in PD. In these 2 conditions, EDS seems to be associated with different causes.

Study of microbial contamination and dosing accuracy of oral dispensers

BACKGROUND AND OBJECTIVE

The optimal administration of liquid medications requires accurate dose delivery. This is particularly important in the treatment of infants and children, as well as elderly people, who are more sensitive to dosage errors. Previous studies revealed significant dosage inaccuracies with measuring spoons. Oral syringes are therefore generally recommended instead. There is no data on the efficacy of standard cleaning techniques, and consequently on the degree of microbial contamination associated with the repeated use of oral syringes. This study aimed to investigate the level and types of microorganisms found in oral dispensers subjected to simulated in-use conditions. In addition, the dosing accuracy of the oral dispensers is compared with that of measuring spoons supplied and designed for use with specific medications.

METHODS

Exadoral 5 mL oral dispensers from B. Braun Melsungen AG (Melsungen, Germany) were subjected to simulated in-use conditions and microbial assay. Six different liquid medications representing different substance classes were included. The test lasted 4-15 days with two to four doses withdrawn according to dosage recommendations. Dosing accuracy was assessed using six representative amoxicillin suspensions available on the German market after withdrawing 1.25, 2.5 and 5 mL that correspond to ¼, ½ and full measuring spoons.

RESULTS AND DISCUSSION

Low counts of Micrococcus luteus, Micrococcus lylae, Staphylococcus epidermidis, Staphylococcus chromogenes as well as Bacillus species and Candida lusitaniae may contaminate the interior surface of the oral dispenser, but the microbial count was below the accepted limit of microbial counts permissible for drinking water over the whole test period. Hence, oral dispensers may be considered safe, provided that cleaning procedures are followed exactly. Moreover, oral dispensers, although not specifically designed for the tested medication, showed much higher dosing accuracy in comparison with the specifically designed measuring spoons.

CONCLUSION

The present study revealed that oral dispensers are accurate measuring devices for the safe administration of liquid medication. Pharmacists and physicians should encourage their patients to use oral dispensers routinely in practice.

Hosts as ecological traps for the vector of Lyme disease

Vectors of infectious diseases are generally thought to be regulated by abiotic conditions such as climate or the availability of specific hosts or habitats. In this study we tested whether blacklegged ticks, the vectors of Lyme disease, granulocytic anaplasmosis and babesiosis can be regulated by the species of vertebrate hosts on which they obligately feed. By subjecting field-caught hosts to parasitism by larval blacklegged ticks, we found that some host species (e.g. opossums, squirrels) that are abundantly parasitized in nature kill 83-96% of the ticks that attempt to attach and feed, while other species are more permissive of tick feeding. Given natural tick burdens we document on these hosts, we show that some hosts can kill thousands of ticks per hectare. These results indicate that the abundance of tick vectors can be regulated by the identity of the hosts upon which these vectors feed. By simulating the removal of hosts from intact communities using empirical models, we show that the loss of biodiversity may exacerbate disease risk by increasing both vector numbers and vector infection rates with a zoonotic pathogen.

Subversion of Toll-like receptor signaling by a unique family of bacterial Toll/interleukin-1 receptor domain-containing proteins

Pathogenic microbes have evolved sophisticated molecular strategies to subvert host defenses. Here we show that virulent bacteria interfere directly with Toll-like receptor (TLR) function by secreting inhibitory homologs of the Toll/interleukin-1 receptor (TIR) domain. Genes encoding TIR domain containing-proteins (Tcps) were identified in Escherichia coli CFT073 (TcpC) and Brucella melitensis (TcpB). We found that TcpC is common in the most virulent uropathogenic E. coli strains and promotes bacterial survival and kidney pathology in vivo. In silico analysis predicted significant tertiary structure homology to the TIR domain of human TLR1, and we show that the Tcps impede TLR signaling through the myeloid differentiation factor 88 (MyD88) adaptor protein, owing to direct binding of Tcps to MyD88. Tcps represent a new class of virulence factors that act by inhibiting TLR- and MyD88-specific signaling, thus suppressing innate immunity and increasing virulence.

MMP-2/gelatinase A is a gene product of human adult articular chondrocytes and is increased in osteoarthritic cartilage

OBJECTIVE

Collagen fibril degeneration involves initially the cleavage within the triple helix by the collagenases (1 and 3), but then mainly involves also the gelatinases, of which gelatinase A (MMP-2) appears to play a central role in many tissues. The objective of this study was to determine the quantitative expression levels as well as the distribution in normal and osteoarthritic cartilage of gelatinase A and in cultured articular chondrocytes with and without stimulation by Il-1beta.

METHODS

Conventional and online PCR technology and immunohistochemistry were used to determine MMP-2 expression levels on the mRNA and protein level.

RESULTS

Conventional PCR analysis could demonstrate the presence of MMP-2 mRNA in normal and osteoarthritic chondrocytes. Online quantitative PCR confirmed the presence of MMP-2 mRNA expression in normal articular chondrocytes in vivo (and in vitro). An increase of 5x (p < 0.001) was observed in osteoarthritic cartilage in vivo. Of note, no significant up-regulation of gelatinase A was observed by Il-1beta in vitro. Immunostaining for gelatinase A confirmed the presence of MMP-2 with mono- and polyclonal antibodies in normal and osteoarthritic chondrocytes with somewhat higher levels observed in the latter.

CONCLUSIONS

The presented results confirm the increased expression of gelatinase A by osteoarthritic articular chondrocytes as previously described. Of note, also normal adult articular chondrocytes expressed significant amounts of gelatinase A in vivo and in vitro suggesting gelatinase A as being also involved in physiological collagen turnover in human adult articular cartilage.

MMP-8 is only a minor gene product of human adult articular chondrocytes of the knee

OBJECTIVE

The initial degradation of collagen fibrils during osteoarthritic cartilage destruction depends on the cleavage at the collagenase site, for which there exist three major candidate enzymes: collagenase 1 (MMP-1), collagenase 2 (MMP-8), and collagense 3 (MMP-13). The objective of this study was to determine the quantitative expression as well as distribution levels in normal and osteoarthritic cartilage and synovium and in cultured articular chondrocytes with and without stimulation by Il-1 beta.

METHODS

Conventional and online PCR technology and immunohistochemistry were used to determine MMP-8 expression levels on the mRNA and protein level.

RESULTS

Whereas conventional PCR analysis could demonstrate the presence of MMP-8 mRNA in normal and osteoarthritic chondrocytes, online quantitative PCR showed that only very minor amounts of MMP-8 mRNA expression is found in articular chondrocytes in vivo (and in vitro) and that there is no significant upregulation in osteoarthritic cartilage in vivo nor by Il-1 beta in vitro. The in vivo results were confirmed by the absence of significant protein staining with monoclonal antibodies for MMP-8 in normal and osteoarthritic chondrocytes.

CONCLUSIONS

The presented results confirm the presence of a very minor MMP-8 expression by articular chondrocytes, but clearly question the hypothesis that MMP-8 is a major cartilage matrix degrading protease and is involved in enhanced cartilage matrix breakdown in osteoarthritic cartilage degeneration or by Il-1 beta stimulation in vitro.

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Gunshot wound of the abdomen with cerebral embolization

A distinctly rare case of a bullet embolus to the internal carotid artery following an abdominal gunshot wound is reported. Unusual aspects of the case are discussed with references to the literature. Pathways the bullet may have traversed to reach its final location are proposed.