Genome-wide investigation of the LARP gene family: focus on functional identification and transcriptome profiling of ZmLARP6c1 in maize pollen.

BACKGROUND: The La-related proteins (LARPs) are a superfamily of RNA-binding proteins associated with regulation of gene expression. Evidence points to an important role for post-transcriptional control of gene expression in germinating pollen tubes, which could be aided by RNA-binding proteins. RESULTS: In this study, a genome-wide investigation of the LARP proteins in eight plant species was performed. The LARP proteins were classified into three families based on a phylogenetic analysis. The gene structure, conserved motifs, cis-acting elements in the promoter, and gene expression profiles were investigated to provide a comprehensive overview of the evolutionary history and potential functions of ZmLARP genes in maize. Moreover, ZmLARP6c1 was specifically expressed in pollen and ZmLARP6c1 was localized to the nucleus and cytoplasm in maize protoplasts. Overexpression of ZmLARP6c1 enhanced the percentage pollen germination compared with that of wild-type pollen. In addition, transcriptome profiling analysis revealed that differentially expressed genes included PABP homologous genes and genes involved in jasmonic acid and abscisic acid biosynthesis, metabolism, signaling pathways and response in a Zmlarp6c1::Ds mutant and ZmLARP6c1-overexpression line compared with the corresponding wild type. CONCLUSIONS: The findings provide a basis for further evolutionary and functional analyses, and provide insight into the critical regulatory function of ZmLARP6c1 in maize pollen germination.

Diagnosis of Mild-to-moderate Idiopathic Median Neuropathy at the Carpal Tunnel Based on Signs and Symptoms is Discordant From Diagnosis Based on Electrodiagnostic Studies and Ultrasound.

BACKGROUND: Although idiopathic median neuropathy at the carpal tunnel (IMNCT) is objective and verifiable, distinction of normal and abnormal nerves is imprecise and probabilistic. The associated symptoms and signs (carpal tunnel syndrome [CTS]) vary, particularly for nonsevere (mild and moderate) median neuropathy. Discordance between diagnosis of mild or moderate median neuropathy at the carpal tunnel using symptoms and signs and diagnosis based on objective tests is a measure of the potential for overdiagnosis and overtreatment. QUESTION/PURPOSE: What is the difference in the estimated prevalence of mild-to-moderate IMNCT using nonsevere signs and symptoms compared with the estimated prevalence using electrodiagnostic studies (EDS) and ultrasound (US)? METHODS: We used data from an existing cross-sectional data registry. To create this registry, between January 2014 and January 2019, we considered all new adult English-speaking people who had an EDS that included the median nerve or people with a diagnosis of CTS who did not have surgery yet. A small and unrecorded number of people declined participation. The cross-sectional area of the median nerve at the distal wrist crease using US in people who already had EDS was measured. People with a diagnosis of CTS underwent both EDS and US. The six signs and symptoms of Carpal Tunnel Syndrome 6 (CTS-6, a validated tool to estimate the probability of IMNCT using ratings of symptoms and signs of CTS) were recorded. This resulted in a registry of 185 participants; we excluded 75 people for obvious, severe IMNCT (defined as nonrecordable nerve conduction velocity, thenar atrophy, or greater than 5 mm 2-point discrimination). Three of the 110 qualifying patients had missing information on ethnicity or race, but we accounted for this in our final analysis. Without a reference standard, as is the case with IMNCT, latent class analysis (LCA) can be used to establish the probability that an individual has specific pathophysiologic findings. LCA is a statistical method that identifies sets of characteristics that tend to group together. This technique has been used, for example, in diagnosing true scaphoid fractures among suspected fractures based on a combination of demographic, injury, examination, and radiologic variables. The prevalence of mild-to-moderate IMNCT was estimated in two LCAs using four signs and symptoms characteristic of mild-to-moderate IMNCT, as well as EDS and US measures of median neuropathy. RESULTS: The estimated prevalence of mild-to-moderate IMNCT based on signs and symptoms was 73% (95% CI 62% to 81%), while the estimated prevalence using EDS and US measurements was 51% (95% CI 37% to 65%). CONCLUSION: The notable discordance of 22% between the estimated prevalence of mild-to-moderate IMNCT using signs and symptoms and prevalence based on EDS and US criteria, and the overlapping CIs of the probability estimations, indicate considerable uncertainty and a corresponding notable potential for underdiagnosis or overdiagnosis. When signs and symptoms suggest mild-to-moderate median neuropathy and surgery is being considered, patients and clinicians might consider additional testing, such as EDS or US, to increase the probability of actual median neuropathy that can benefit from surgery. We might benefit from a more accurate and reliable diagnostic strategy or tool for mild-to-moderate IMNCT; this might be the focus of a future study. LEVEL OF EVIDENCE: Level III, diagnostic study.

High expression in maize pollen correlates with genetic contributions to pollen fitness as well as with coordinated transcription from neighboring transposable elements.

In flowering plants, gene expression in the haploid male gametophyte (pollen) is essential for sperm delivery and double fertilization. Pollen also undergoes dynamic epigenetic regulation of expression from transposable elements (TEs), but how this process interacts with gene expression is not clearly understood. To explore relationships among these processes, we quantified transcript levels in four male reproductive stages of maize (tassel primordia, microspores, mature pollen, and sperm cells) via RNA-seq. We found that, in contrast with vegetative cell-limited TE expression in Arabidopsis pollen, TE transcripts in maize accumulate as early as the microspore stage and are also present in sperm cells. Intriguingly, coordinate expression was observed between highly expressed protein-coding genes and their neighboring TEs, specifically in mature pollen and sperm cells. To investigate a potential relationship between elevated gene transcript level and pollen function, we measured the fitness cost (male-specific transmission defect) of GFP-tagged coding sequence insertion mutations in over 50 genes identified as highly expressed in the pollen vegetative cell, sperm cell, or seedling (as a sporophytic control). Insertions in seedling genes or sperm cell genes (with one exception) exhibited no difference from the expected 1:1 transmission ratio. In contrast, insertions in over 20% of vegetative cell genes were associated with significant reductions in fitness, showing a positive correlation of transcript level with non-Mendelian segregation when mutant. Insertions in maize gamete expressed2 (Zm gex2), the sole sperm cell gene with measured contributions to fitness, also triggered seed defects when crossed as a male, indicating a conserved role in double fertilization, given the similar phenotype previously demonstrated for the Arabidopsis ortholog GEX2. Overall, our study demonstrates a developmentally programmed and coordinated transcriptional activation of TEs and genes in pollen, and further identifies maize pollen as a model in which transcriptomic data have predictive value for quantitative phenotypes.

Nerve Conditions of the Upper Limb: How Not to Miss or Mismanage.

There are several issues associated with nerve compression syndromes of the upper limb; ultrasonography is a useful diagnostic tool. The orthopaedic surgeon should know how to evaluate and treat patients who do not obtain expected relief following carpal or cubital tunnel release, and also be knowledgeable about the workup and evaluation of patients with conditions of debatable pathology and treatment, such as radial tunnel syndrome or pronator syndrome. Recent studies on suprascapular neuropathy include discussions about the pathophysiology and etiology of the condition, its natural history, and who might benefit from surgery.

A cost-effective maize ear phenotyping platform enables rapid categorization and quantification of kernels.

High-throughput phenotyping systems are powerful, dramatically changing our ability to document, measure, and detect biological phenomena. Here, we describe a cost-effective combination of a custom-built imaging platform and deep-learning-based computer vision pipeline. A minimal version of the maize (Zea mays) ear scanner was built with low-cost and readily available parts. The scanner rotates a maize ear while a digital camera captures a video of the surface of the ear, which is then digitally flattened into a two-dimensional projection. Segregating GFP and anthocyanin kernel phenotypes are clearly distinguishable in ear projections and can be manually annotated and analyzed using image analysis software. Increased throughput was attained by designing and implementing an automated kernel counting system using transfer learning and a deep learning object detection model. The computer vision model was able to rapidly assess over 390 000 kernels, identifying male-specific transmission defects across a wide range of GFP-marked mutant alleles. This includes a previously undescribed defect putatively associated with mutation of Zm00001d002824, a gene predicted to encode a vacuolar processing enzyme. Thus, by using this system, the quantification of transmission data and other ear and kernel phenotypes can be accelerated and scaled to generate large datasets for robust analyses.

Use of Ultrasound in Patients With Carpal Tunnel Syndrome: A Cost-Effective Solution to Reduce Delays in Surgical Care.

PURPOSE: Currently, electrodiagnostic testing, which comprises electromyogram (EMG) and nerve conduction studies (NCS), is the most commonly used method for confirming the clinical diagnosis of carpal tunnel syndrome (CTS). Electromyogram and NCS can be costly, can require multiple visits, may induce anxiety, and may be painful for patients. The purpose of this study was to determine whether replacing EMG/NCS with ultrasound (US), performed by the treating surgeon, to diagnose CTS decreases time to surgery and the number of office visits. METHODS: We retrospectively reviewed a database that consisted of patients who presented to our department with numbness and/or tingling in the hand(s). We assessed the patients' histories for any subsequent carpal tunnel release, dates of diagnosis, dates of surgery, the number of CTS-related medical visits, and diagnostic methods employed. A fellowship-trained hand surgeon performed US examination, and the patients were referred for EMG/NCS testing. We collected data prior to surgery using the Boston Carpal Tunnel Questionnaire to evaluate symptom severity scale and functional status scale scores. We performed linear regression to assess differences in the time to surgery and the number of medical visits prior to carpal tunnel release. RESULTS: Patients who had the diagnosis confirmed by the surgeon using US (n = 34) underwent surgical intervention 3-4 weeks earlier, with 1.8 fewer medical visits on average than the number of medical visits for those who had their diagnosis confirmed using EMG/NCS (n = 98). CONCLUSIONS: If a confirmatory method for the diagnosis of CTS is required or desired by the treating surgeon, surgeon-conducted US might have an impact on the efficiency of care for patients with CTS. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

Team working part 9: dealing with frustration.

John Fowler, Educational Consultant, explores ways to enhance teamwork.

From staff nurse to nurse consultant: Team working part 8: the multidisciplinary team.

John Fowler, Educational Consultant, explores ways to enhance teamwork.

Does Patient Sex Affect Ultrasound Cutoff Values for Severity Grading of Carpal Tunnel Syndrome?

PURPOSE: A growing body of evidence supports ultrasound (US) as an alternative first-line confirmatory test for carpal tunnel syndrome (CTS). Recent studies have demonstrated a correlation of US cross-sectional area with electrodiagnostic (EDX)-determined severity; however, it is unclear whether patient sex affects the cutoff values used for determining severity. The purpose of this study was to determine if patient sex affects US graded severity when using EDX as the reference standard. METHODS: A cohort of 367 women and 46 men, aged 18-90 years, from 1 orthopedic hand surgeon's practice underwent EDX and US. Distal motor latency and distal sensory latency of the median nerve were recorded. Severity was classified using a modified Bland severity scale. The US measurements of the cross-sectional area of the median nerve at the wrist crease were acquired by a fellowship-trained hand surgeon. Separate receiver operator characteristic curve analyses of the male and female groups were performed for US cutoff values. RESULTS: The cutoff value in both the female (F) and male (M) patients was 11 mm2 for mild (area under the curve = 0.76 F; 0.78 M), 12 mm2 for moderate (area under the curve = 0.75 F; 0.73 M), and 13 mm2 for severe (area under the curve = 0.75 F; 0.71 M) CTS. The sensitivity of the cutoffs for mild, moderate, and severe CTS in the female and male groups was 49% and 56%, 44% and 50%, and 49% and 44%, respectively. The specificity of the cutoffs for mild, moderate, and severe CTS in the female and male groups was 75% and 79%, 74% and 82%, and 83% and 78%, respectively. CONCLUSIONS: Patient sex does not appear to have a significant impact on the determination of CTS severity graded using US cutoff values. Ultrasound can be used to grade the severity of CTS with a 75% to 85% specificity but low sensitivity. A cutoff value of 13 mm2 can be used to classify CTS as severe. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

Team working part 2: Team meetings.

John Fowler, Educational Consultant, explores the pitfalls of meetings, and how to make the most of them.

Team working part 5: Everyone is valuable.

John Fowler, Educational Consultant, explores how to survive your nursing career.

From staff nurse to nurse consultant.

John Fowler, Educational Consultant, explores ways to enhance teamwork.

Team working part 3: leading a team.

John Fowler, Educational Consultant, explores the qualities that enhance leadership in clinical practice.

Team working part 4: managing a team.

John Fowler, Educational Consultant, explores the skills required to successfully manage a team.

From staff nurse to nurse consultant: Team working part 7: developing a positive ethos.

John Fowler, Educational Consultant, explores ways to enhance teamwork.

Team working part 1: Nursing is a team profession.

John Fowler, Educational Consultant, explores how to survive your nursing career.

From staff nurse to nurse consultant: Academic essays part 7: demonstrating depth of writing.

John Fowler, Educational Consultant, explores academic writing.

Academic essays part 8: managing the literature.

John Fowler, Educational Consultant, explores academic writing.

Effect of Insurance Type on Access to Orthopedic Care for Pediatric Trigger Thumb.

PURPOSE: To assess the effect of type of insurance coverage on the ability of a pediatric patient to obtain an outpatient orthopedic appointment for trigger thumb. METHODS: A list of 200 orthopedic practices in 4 states were contacted and presented with a fictitious 3-year-old patient with trigger thumb. The patient was presented as having Blue Cross Blue Shield Insurance during the first call and Medicaid during the second call. Data regarding whether an appointment was offered or denied were recorded. RESULTS: Of the 200 practices, 81 were excluded, 22 because they did not answer the calls, 25 needed the patient's social security number, 19 needed medical records, 5 had no hand surgeon in the practice, and 10 would not see any children at all. Of the 119 practices included in the analysis, the private insurance patient was able to get an appointment 51.3% of the time whereas the Medicaid patient was able to get an appointment in 26.9% of instances. CONCLUSIONS: There is a significant effect of insurance status on the ability of pediatric patients with trigger thumb to obtain outpatient orthopedic appointments. CLINICAL RELEVANCE: Pediatric patients with Medicaid face greater barriers to accessing proper care for trigger thumb than patients with private insurance.

Elbow Biomechanics: Bony and Dynamic Stabilizers.

The elbow positions the hand in a stable manner relative to the trunk while allowing flexion and extension as well as forearm rotation at varying shoulder positions. Its ability to perform this task without joint subluxation is accomplished through a combination of bony congruency, ligamentous restraint, and dynamic stabilization. This article reviews the bony and dynamic contributors to elbow stability and kinematics. Bony stability is conferred through the morphology of the humeroulnar, humeroradial, and radioulnar joints. Depending on the arm position relative to the trunk and the degree of elbow flexion, the bony contribution will vary. Dynamic elbow stabilizers confer stability through the activation of various muscles that cross the elbow. These forces help resist valgus and varus forces and may also increase bony stability by generating compressive forces. The goal of this article is to review the literature surrounding the biomechanics of bony and dynamic stabilizers of the elbow while drawing clinically relevant biomechanical observations.