Association between electrodiagnosis and neuromuscular ultrasound in the diagnosis and assessment of severity of carpal tunnel syndrome.

BACKGROUND: Neuromuscular ultrasound plays an increasing role in diagnosing carpal tunnel syndrome (CTS). There are limited data supporting the correlation between the electrodiagnostic studies and ultrasound measurements in CTS. OBJECTIVE: To assess the association between different electrodiagnostic severities and ultrasound measurements of the median nerve in CTS. DESIGN: A retrospective cohort study. SETTING: An academic tertiary care center. PATIENTS: Patients 18 years or older evaluated with upper limb electrodiagnostic studies and neuromuscular ultrasound. MAIN OUTCOME MEASUREMENT: Ultrasound measurements of the median nerve cross-sectional area (CSA) at the wrist and the calculated wrist-to-forearm ratio (WFR) were compared with the electrodiagnostic severity (normal, mild, moderate, and severe). Mean analysis and analysis of variance test (α = 0.05) were performed to assess the association. RESULTS: A total of 1359 limbs were identified. There was a statistically significant association between electrodiagnostic severity of CTS and median nerve CSA at the wrist (p < .001), as well as the WFR (p < .001). The mean median nerve CSA at the wrist and WFR were 7.01 ± 2.06 mm2 (95% CI: 6.80-7.20) and 1.24 ± 0.36 (95% CI: 1.16-1.24) in electrodiagnostically normal median nerves, 10.47 ± 2.82 mm2 (95% CI: 10.25-10.75) and 2.06 ± 0.67 (95% CI: 2.04-2.16) in electrodiagnostically mild CTS, 12.95 ± 4.74 mm2 (95% CI: 12.41-13.59) and 2.49 ± 1.04 (95% CI: 2.37, 2.63) in electrodiagnostically moderate CTS, and 14.69 ± 5.38 mm2 (95% CI: 13.95-15.44) and 2.71 ± 1.02 (95% CI: 2.56-2.84) in electrodiagnostically severe CTS, respectively. CONCLUSION: This study suggests a direct association between electrodiagnostic severity and ultrasound measurements of the median nerve in patients with suspected CTS.

A high-quality draft genome sequence of Neonectria faginata, causative agent of beech bark disease of Fagus grandifolia.

The draft genome of Neonectria faginata was sequenced with Oxford Nanopore and Illumina 250 bp paired-end sequencing technologies. The assembled genome was 42.9 Mb distributed over 24 contigs, with N50 of 4.4 Mb and 98.6% BUSCO completeness. This genome sequence will aid in understanding N. faginata population structure and ecology.

Complete sternal-sparing left ventricular assist device implantation is associated with improved postoperative mobility.

Left ventricular assist device (LVAD) implantation via a complete sternal-sparing (CSS) technique is gaining interest due to several potential benefits. We hypothesized that the CSS approach for HeartMate 3 (HM3) LVAD implantation improves postoperative mobility and physical independence compared to full sternotomy (FS). We retrospectively reviewed patients who were implanted with a commercial HM3 at our institution from September 2017 to August 2018. The Activity Measure for Post-Acute Care short forms and Functional Independence Measure scores were used to assess the patient's physical limitations postoperatively. A total of 43 patients were included in the study: 27 (63%) CSS patients and 16 (37%) FS patients. At postoperative day 3, the CSS cohort demonstrated improved mobility based on Activity Measure for Post-Acute Care scores compared to the FS group; 40% of the CSS cohort versus 67% of the FS cohort remained 100% impaired. The CSS cohort also demonstrated greater postoperative independence in the Functional Independence Measure sit-to-stand metric with 78% of the CSS cohort achieving modified or complete independence by postoperative day 15 compared to only 21% of the FS patients. These early data suggest that the CSS approach for HM3 LVAD implantation improves postoperative mobility and functional independence compared to FS.

Dense nanolipid fluid dispersions comprising ibuprofen: Single step extrusion process and drug properties.

Dense nanolipid fluid (DNLF) dispersions are highly concentrated aqueous dispersions of lipid nanocarriers (LNCs) with more than 1015 lipid particles per cubic centimeter. Descriptions of dense nanolipid fluid dispersions in the scientific literature are rare, and they have not been used to encapsulate drugs. In this paper we describe the synthesis of DNLF dispersions comprising ibuprofen using a recently described twin-screw extrusion process. We report that such dispersions are stable, bind ibuprofen tightly and yet provide high transdermal drug permeation. Ibuprofen DNLF dispersions prepared according to the present study provide up to five times greater flux of the pharmacologically active S-ibuprofen isomer through human skin than a commercially available racemic ibuprofen emulsion product. We demonstrate scaling up the twin-screw extrusion method to pilot production for a stable, highly permeating ibuprofen DNLF composition based on excipients approved by the US FDA for use in topical products as a key step towards development of a commercially viable, FDA approvable topical ibuprofen medicine to treat osteoarthritis, which has never before been accomplished.

One-step extrusion of concentrated lidocaine lipid nanocarrier (LNC) dispersions.

Lipid nanocarriers (LNCs) have been successfully produced by many methods including high pressure homogenization, sonication and microemulsification, but it remains very difficult to produce dispersions with greater than 30% LNCs, volume average particle diameter less than 150 nm, and concentration of drugs useful for topical products. This research is the first to propose and demonstrate extrusion to manufacture highly concentrated drug containing LNC dispersions continuously and economically in a single step. By treating crude emulsions in a twin-screw extruder which has sections for homogenizing, mixing and fast-cooling inside the extruder, lidocaine-loaded LNC dispersions were successfully generated with lipid concentration up to 60% and particle diameters less than 50 nm. Electrical conductivity and birefringence measurements indicate that in the lidocaine system, lamellar microemulsions are intermediate structures and compositions with low lipid concentrations that do not present evidence of lamellar structures fail to give nanoparticles when processed. This paper also presents a new method for measuring kinetics of drug release from nanoparticles based on pH stat titration. Sufficiently precise data from pH stat titration allows determination of rate laws for release occurring on a time scale of minutes versus hours or days. The release rate of lidocaine from extruded 35% lipid nanoparticles was constant (zero order release kinetics) through the first hour (40% of drug release), a valuable property for drug delivery.

Characterization of mating type genes in heterothallic Neonectria species, with emphasis on N. coccinea, N. ditissima, and N. faginata.

Neonectria ditissima and N. faginata are canker pathogens involved in an insect-fungus disease complex of American beech (Fagus grandifolia) in North America commonly known as beech bark disease (BBD). In Europe, both N. ditissima and N. coccinea are involved in BBD on European beech (Fagus sylvatica). Field observations across the range of BBD indicate ascospores to be the dominant spore type in the environment. Several studies report a heterothallic (self-sterile) mating strategy for Neonectria fungi, but one study reported homothallism (self-fertility) for N. ditissima. As such, investigations into mating strategy are important for understanding both the disease cycle and population genetics of Neonectria. This is particularly important in the United States given that over time N. faginata dominates the BBD pathosystem despite high densities of nonbeech hosts for N. ditissima. This study utilized whole-genome sequences of BBD-associated Neonectria spp. along with other publicly available Neonectria and Corinectria genomes and in vitro mating assays to characterize mating type (MAT) locus and confirm thallism for select members of Neonectria and Corinectria. MAT gene-specific primer pairs were developed to efficiently characterize the mating types of additional single-ascospore strains of N. ditissima, N. faginata, and N. coccinea and several other related species lacking genomic data. These assays also confirmed the sexual compatibility among N. ditissima strains from different plant hosts. Maximum likelihood phylogenetic analyses of both MAT1-1-1 and MAT1-2-1 sequences recovered trees with similar topology to previously published phylogenies of Neonectria and Corinectria. The results of this study indicate that all Neonectria and Corinectria tested are heterothallic based on our limited sampling and, as such, thallism cannot help explain the inevitable dominance of N. faginata in the BBD pathosystem.

Drought and plant litter chemistry alter microbial gene expression and metabolite production.

Drought represents a significant stress to microorganisms and is known to reduce microbial activity and organic matter decomposition in Mediterranean ecosystems. However, we lack a detailed understanding of the drought stress response of microbial decomposers. Here we present metatranscriptomic and metabolomic data on the physiological response of in situ microbial communities on plant litter to long-term drought in Californian grass and shrub ecosystems. We hypothesised that drought causes greater microbial allocation to stress tolerance relative to growth pathways. In grass litter, communities from the decade-long ambient and reduced precipitation treatments had distinct taxonomic and functional profiles. The most discernable physiological signatures of drought were production or uptake of compatible solutes to maintain cellular osmotic balance, and synthesis of capsular and extracellular polymeric substances as a mechanism to retain water. The results show a clear functional response to drought in grass litter communities with greater allocation to survival relative to growth that could affect decomposition under drought. In contrast, communities on chemically more diverse and complex shrub litter had smaller physiological differences in response to long-term drought but higher investment in resource acquisition traits across precipitation treatments, suggesting that the functional response to drought is constrained by substrate quality. Our findings suggest, for the first time in a field setting, a trade off between microbial drought stress tolerance, resource acquisition and growth traits in plant litter microbial communities.

Carbon Use Efficiency and Its Temperature Sensitivity Covary in Soil Bacteria.

The strategy that microbial decomposers take with respect to using substrate for growth versus maintenance is one essential biological determinant of the propensity of carbon to remain in soil. To quantify the environmental sensitivity of this key physiological trade-off, we characterized the carbon use efficiency (CUE) of 23 soil bacterial isolates across seven phyla at three temperatures and with up to four substrates. Temperature altered CUE in both an isolate-specific manner and a substrate-specific manner. We searched for genes correlated with the temperature sensitivity of CUE on glucose and deemed those functional genes which were similarly correlated with CUE on other substrates to be validated as markers of CUE. Ultimately, we did not identify any such robust functional gene markers of CUE or its temperature sensitivity. However, we found a positive correlation between rRNA operon copy number and CUE, opposite what was expected. We also found that inefficient taxa increased their CUE with temperature, while those with high CUE showed a decrease in CUE with temperature. Together, our results indicate that CUE is a flexible parameter within bacterial taxa and that the temperature sensitivity of CUE is better explained by observed physiology than by genomic composition across diverse taxa. We conclude that the bacterial CUE response to temperature and substrate is more variable than previously thought.IMPORTANCE Soil microbes respond to environmental change by altering how they allocate carbon to growth versus respiration-or carbon use efficiency (CUE). Ecosystem and Earth System models, used to project how global soil C stocks will continue to respond to the climate crisis, often assume that microbes respond homogeneously to changes in the environment. In this study, we quantified how CUE varies with changes in temperature and substrate quality in soil bacteria and evaluated why CUE characteristics may differ between bacterial isolates and in response to altered growth conditions. We found that bacterial taxa capable of rapid growth were more efficient than those limited to slow growth and that taxa with high CUE were more likely to become less efficient at higher temperatures than those that were less efficient to begin with. Together, our results support the idea that the CUE temperature response is constrained by both growth rate and CUE and that this partly explains how bacteria acclimate to a warming world.

Palmaris Longus Tendinopathy Diagnosed With Ultrasound: A Case Report.

This patient is a 52-year-old woman who was referred to the electrodiagnostic (EDX) laboratory for evaluation of pain and paresthesias of the left upper limb. The results of the EDX study were normal. However, ultrasound revealed tendinopathy of the palmaris longus tendon, manifested by increased hypoechogenicity, caliber, and tenderness in response to sonopalpation compared to the right side. To the authors' knowledge there are no reported cases of palmaris longus tendinopathy diagnosed with ultrasound. This case supports the use of point-of-care ultrasound to explore other possible causes of pathology in patients with paresthesias in the context of normal findings on an EDX study. LEVEL OF EVIDENCE: V.

Improving the Performance Time and Accuracy of Ultrasound-Guided Interventions: A Randomized Controlled Double-Blind Trial of the Line-of-Sight Approach and the "APPLES" Mnemonic.

OBJECTIVES: To determine whether the line-of-sight approach improved the performance time and accuracy of ultrasound (US)-guided needle placement targeting the subdeltoid bursa in a cadaver among novice operators compared to the side approach. A secondary objective was to determine whether participants thought the APPLES (angle, position, perpendicular, line up, entry, sweep) mnemonic was a helpful guide for performing the procedure. METHODS: Medical students and residents were randomized into either a line-of-sight or side approach group and then crossed over to the other group. The procedure time was determined by 2 blinded reviewers. A survey was administered to determine which method participants preferred and whether they thought the APPLES mnemonic was helpful. A paired t test was used to compare the performance time, and the McNemar test was used to compare the accuracy of the methods. RESULTS: Among the 110 participants, the performance time with the line-of-sight approach (mean, 14.4 seconds; SD, 9.95 seconds) was significantly decreased compared to the side approach (mean, 18.6 seconds; SD, 10.1 seconds; P = .00029). Additionally, participants who only hit the target using one method were more likely to hit the target in 30 seconds using the line-of-sight approach (P = .035). In total, 72.7% of participants preferred the line-of-sight approach over the side approach, and 88.2% of participants thought that APPLES mnemonic was useful. CONCLUSIONS: This study highlights the finding that positioning of the operator is important in performing US-guided interventions, and the line-of-sight approach may improve the performance time and accuracy among novice operators. Furthermore, the APPLES mnemonic serves as a useful educational tool for teaching US-guided interventional procedures.

Species associations overwhelm abiotic conditions to dictate the structure and function of wood-decay fungal communities.

Environmental conditions exert strong controls on the activity of saprotrophic microbes, yet abiotic factors often fail to adequately predict wood decomposition rates across broad spatial scales. Given that species interactions can have significant positive and negative effects on wood-decay fungal activity, one possibility is that biotic processes serve as the primary controls on community function, with abiotic controls emerging only after species associations are accounted for. Here we explore this hypothesis in a factorial field warming- and nitrogen-addition experiment by examining relationships among wood decomposition rates, fungal activity, and fungal community structure. We show that functional outcomes and community structure are largely unrelated to abiotic conditions, with microsite and plot-level abiotic variables explaining at most 19% of the total variability in decomposition and fungal activity, and 2% of the variability in richness and evenness. In contrast, taxonomic richness, evenness, and species associations (i.e., co-occurrence patterns) exhibited strong relationships with community function, accounting for 52% of the variation in decomposition rates and 73% in fungal activity. A greater proportion of positive vs. negative species associations in a community was linked to strong declines in decomposition rates and richness. Evenness emerged as a key mediator between richness and function, with highly even communities exhibiting a positive richness-function relationship and uneven communities exhibiting a negative or null response. These results suggest that community-assembly processes and species interactions are important controls on the function of wood-decay fungal communities, ultimately overwhelming substantial differences in abiotic conditions.

Fungi exposed to chronic nitrogen enrichment are less able to decay leaf litter.

Saprotrophic fungi are the primary decomposers of plant litter in temperate forests, and their activity is critical for carbon (C) and nitrogen (N) cycling. Simulated atmospheric N deposition is associated with reduced fungal biomass, shifts in fungal community structure, slowed litter decay, and soil C accumulation. Although rarely studied, N deposition may also result in novel selective pressures on fungi, affecting evolutionary trajectories. To directly test if long-term N enrichment reshapes fungal responses to N, we isolated decomposer fungi from a long-term (28 yr) N-addition experiment and used a common garden approach to compare growth rates and decay abilities of isolates from control and N-amended plots. Both growth and decay were significantly altered by long-term exposure to N enrichment. Changes in growth rates were idiosyncratic, as different species grew either more quickly or more slowly after exposure to N, but litter decay by N isolates was consistent and generally lower compared to control isolates of the same species, a response not readily reversed when N isolates were grown in control (low N) environments. Changes in fungal responses accompany and perhaps drive previously observed N-induced shifts in fungal diversity, community composition, and litter decay dynamics.

Cryogenic electron microscopy study of nanoemulsion formation from microemulsions.

We examine a process of preparing oil-in-water nanoemulsions by quenching (diluting and cooling) precursor microemulsions made with nonionic surfactants and a cosurfactant. The precursor microemulsion structure is varied by changing the concentration of the cosurfactant. Water-continuous microemulsions produce initial nanoemulsion structures that are small and simple, mostly unilamellar vesicles, but microemulsions that are not water-continuous produce initial nanoemulsion structures that are larger and multilamellar. Examination of these structures by cryo-electron microscopy supports the hypothesis that they are initially vesicular structures formed via lamellar intermediate structures, and that if the lamellar structures are too well ordered they fail to produce small simple structures.

User's guide to a randomized trial about an orthopaedic implant.

Evidence-based orthopaedic surgery emphasizes the need to properly appraise the available literature to evaluate the efficacy of therapeutic interventions before accepting them into daily practice. A properly designed and well-conducted randomized controlled trial provides a very high level of evidence on which to guide clinical decisions in orthopaedic surgery. The purpose of this article is to assist orthopaedic surgeons with this process, focusing on critically reviewing randomized controlled trials.