Pain in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting the motor neurons. It leads to progressive limb weakness, dysphagia, dysarthria, and respiratory failure. Although ALS is described as a disease of “painless weakness,” more recent literature has revealed that pain is a prevalent part of the disease. Commonly, patients may report pain associated with ALS that can be described as either nociceptive, neuropathic, or spasticity/cramping. A thorough pain assessment in patients with ALS should always be undertaken. While evidence to support their use is largely lacking, anecdotal reports support several nonpharmacologic and pharmacologic treatment options that may be offered.

Top Ten Tips Palliative Care Clinicians Should Know About Strokes

Stroke is a common cause of long-term disability and death, which leaves many patients with significant and unique palliative care (PC) needs. Shared decision-making for patients with stroke poses distinct challenges due to the sudden nature of stroke, the uncertainty inherent in prognostication around recovery, and the common necessity of relying on surrogates for decision-making. Patients with stroke suffer from frequently underrecognized symptoms, which PC clinicians should feel comfortable identifying and treating. This article provides 10 tips for palliative clinicians to increase their knowledge and comfort in caring for this important population.

An Atypical and Multifactorial Acute Immune Polyradiculopathy: A Case Report

Clinical diagnosis often focuses on identifying the single cause of a patient's symptoms but it is becoming increasingly recognized that a subset of patients exist where 2 pathological entities coexist. These patients present a particular diagnostic challenge because the first "positive" diagnostic test is not the definitive stopping point in their evaluation. Here, we present the case of a 47-year-old woman with multiple cranial neuropathies and a polyradiculopathy. A significant pleocytosis in the cerebrospinal fluid sparked a broad evaluation which revealed pathologic evidence of sarcoidosis and molecular evidence of neurofascin (NF)-155 and NF-140 antibodies. The pathogenic contribution of these 2 pathologic entities, or interaction, to this patient's case is not clear. Nevertheless, the patient responded robustly to steroids and symptoms significantly improved. This case is a demonstration of the balance between Occam's razor and Hickam's dictum in clinical practice.

Appraisal of Health States Worse Than Death in Patients With Acute Stroke

Objective

To identify health states that patients with acute stroke deem worse than death and to explore potential predictors for these ratings.

Methods

This was a cross-sectional study involving patients admitted to an urban comprehensive stroke center with acute stroke. Participants were asked to rate 10 possible health states/functional outcomes as better or worse than death using a 5-point Likert scale. Principal component analysis (PCA) was used to reduce clusters of correlated ratings to summary components (factors). These components were then analyzed using linear regression to identify possible predictive variables.

Results

Eighty patients participated. The states deemed equal to or worse than death by the majority of participants were relying on a breathing machine (66%) or feeding tube (66%), persistent confusion (62%), inability to communicate with others (58%), and bowel/bladder incontinence (50%). PCA revealed 2 factors of correlated variables: factor 1 composed primarily of relying on a feeding tube or breathing machine, incontinence, chronic pain, and persistent confusion, and factor 2 composed primarily of using a wheelchair, being bedbound, living in a nursing home, and requiring help for activities of daily living. The only significant predictor found was race for factor 1, with black participants finding these states more preferable to death than white participants.

Discussion

A substantial number of patients found multiple common outcomes of stroke to be the same as or worse than death. This highlights the importance of realistic discussions about expected functional outcomes with patients and/or their surrogate decision makers when considering goals of care after stroke.

Detection of Pediatric Upper Extremity Motor Activity and Deficits With Accelerometry

IMPORTANCE

Affordable, quantitative methods to screen children for developmental delays are needed. Motor milestones can be an indicator of developmental delay and may be used to track developmental progress. Accelerometry offers a way to gather real-world information about pediatric motor behavior.

OBJECTIVE

To develop a referent cohort of pediatric accelerometry from bilateral upper extremities (UEs) and determine whether movement can accurately distinguish those with and without motor deficits.

DESIGN, SETTING, AND PARTICIPANTS

Children aged 0 to 17 years participated in a prospective cohort from December 8, 2014, to December 29, 2017. Children were recruited from Ranken Jordan Pediatric Bridge Hospital, Maryland Heights, Missouri, and Washington University School of Medicine in St Louis, St Louis, Missouri. Typically developing children were included as a referent cohort if they had no history of motor or neurological deficit; consecutive sampling and matching ensured equal representation of sex and age. Children with diagnosed asymmetric motor deficits were included in the motor impaired cohort.

EXPOSURES

Bilateral UE motor activity was measured using wrist-worn accelerometers for a total of 100 hours in 25-hour increments.

MAIN OUTCOMES AND MEASURES

To characterize bilateral UE motor activity in a referent cohort for the purpose of detecting irregularities in the future, total activity and the use ratio between UEs were used to describe typically developing children. Asymmetric impairment was classified using the mono-arm use index (MAUI) and bilateral-arm use index (BAUI) to quantify the acceleration of unilateral movements.

RESULTS

A total of 216 children enrolled, and 185 children were included in analysis. Of these, 156 were typically developing, with mean (SD) age 9.1 (5.1) years and 81 boys (52.0%). There were 29 children in the motor impaired cohort, with mean (SD) age 7.4 (4.4) years and 16 boys (55.2%). The combined MAUI and BAUI (mean [SD], 0.86 [0.005] and use ratio (mean [SD], 0.90 [0.008]) had similar F1 values. The area under the curve was also similar between the combined MAUI and BAUI (mean [SD], 0.98 [0.004]) and the use ratio (mean [SD], 0.98 [0.004]).

CONCLUSIONS AND RELEVANCE

Bilateral UE movement as measured with accelerometry may provide a meaningful metric of real-world motor behavior across childhood. Screening in early childhood remains a challenge; MAUI may provide an effective method for clinicians to measure and visualize real-world motor behavior in children at risk for asymmetrical deficits.

Identification of a critical cysteine in EcoRI DNA methyltransferase by mass spectrometry

EcoRI DNA methyltransferase (MTase) is rapidly inactivated by N-ethylmaleimide with concomitant incorporation of 2 mol of N-ethyl[2-3H]maleimide/mol of functional monomer. Preincubation of the enzyme with either S-adenosylmethionine or DNA reduces the rate of activity loss, whereas preincubation with DNA and the S-adenosylmethionine analog sinefungin completely protects the enzyme from inactivation. An endo proteinase Glu-C digest of N-ethyl[2-3H]maleimide-modified enzyme was prepared and separated by high pressure liquid chromatography. Modified and unmodified cysteine-containing peptides were located and identified by radioactivity, mass spectrometry, and tandem mass spectrometry. In the absence of any ligands, cysteines 25, 116, and 223 are modified by N-ethylmaleimide; in the presence of DNA and sinefungin, Cys-223 is essentially unmodified. Thus, N-ethylmaleimide modification of Cys-223 in EcoRI DNA MTase is responsible for the loss of enzyme activity. Cys-223 is preceded by Asn, and this (or Cys-Asn) occurs with high frequency in adenine and cytosine (N-4) DNA MTases. Direct involvement of cysteine in methyl transfer reactions to adenine N-6 and cytosine N-4 is supported by the similarity of the reactions catalyzed by adenine N-6 and cytosine N-4 DNA MTases, the frequent presence of Asn-flanking Cys, and the importance of Cys-223 to EcoRI MTase function.

Identification of peptides involved in S-adenosylmethionine binding in the EcoRI DNA methylase. Photoaffinity laveling with 8-azido-S-adenosylmethionine

The Mr 38,050 monomeric EcoRI DNA methylase is part of a bacterial restriction-modification system. The methylase transfers the methyl group from S-adenosylmethionine (AdoMet) to the second adenine in the double-stranded DNA sequence 5'-GAATTC-3'. We have used the radiolabeled photoaffinity analog 8-azido-S-adenosylmethionine (8-N3-AdoMet) to identify peptides at the AdoMet binding site in the binary methylase-cofactor analog complex. The dissociation constants in the absence of DNA for the analog and AdoMet are 12.9 and 4.8 microM, respectively. The apparent kcat and Km values, obtained with the double-stranded DNA substrate 5'-CGCGAATTCGCG-3', are 5.0 s-1 and 0.710 microM (8-N3-AdoMet) and 4.3 s-1 and 0.335 microM (AdoMet). Photolabeling by 8-N3-AdoMet occurs upon irradiation with ultraviolet light and is inhibited by AdoMet. Digestion of the adducted methylase with subtilisin generated several radiolabeled peptides. Peptide sequencing from independent photolabeling experiments revealed two radiolabeled peptides containing amino acids 206-212 and 213-221. Instability of the adducted peptides precluded assignment of modified amino acids.

Ecori DNA methylase activity is eliminated upon histidine residue modification

The E. coli EcoRI DNA methylase activity is completely eliminated in five minutes upon incubation with the histidine residue specific reagent diethyl pyrocarbonate. In that two moles of N-ethoxyformylimidazole per mole of methylase are detected spectroscopically upon inactivation and activity is not restored by hydroxylamine, it is likely that activity loss is due to double modification of a single histidine residue. This information is critical in determining the enzymatic mechanism, causes of the pH-activity curve, designing protein mutants and interpreting previous structure-function data.

Slow viscous flow in a syringe

The slow viscous flow in a syringe is modeled by the quasi-steady axisymmetric Stokes equation with a point sink for the needle hole. The governing equations are approximated using nonstandard finite difference formulas optimized for the boundary conditions, and solved numerically using a SOR technique. Streamlines and pressure profiles are computed for a variety of syringe configurations.