Optimizing Recombinant Cas9 Expression: Insights from E. coli BL21(DE3) Strains for Enhanced Protein Purification and Genome Editing.

The CRISPR-Cas9 system is a revolutionary tool in genetic engineering, offering unprecedented precision and efficiency in genome editing. Cas9, an enzyme derived from bacteria, is guided by RNA to edit DNA sequences within cells precisely. However, while CRISPR-Cas9 presents notable benefits and encouraging outcomes as a molecular tool and a potential therapeutic agent, the process of producing and purifying recombinant Cas9 protein remains a formidable hurdle. In this study, we systematically investigated the expression of recombinant SpCas9-His in four distinct Escherichia coli (E. coli) strains (Rosetta2, BL21(DE3), BL21(DE3)-pLysS, and BL21(DE3)-Star). Through optimization of culture conditions, including temperature and post-induction time, the BL21(DE3)-pLysS strain demonstrated efficient SpCas9 protein expression. This study also presents a detailed protocol for the purification of recombinant SpCas9, along with detailed troubleshooting tips. Results indicate successful SpCas9 protein expression using E. coli BL21(DE3)-pLysS at 0.5 mM IPTG concentration. Furthermore, the findings suggest potential avenues for further enhancements, paving the way for large-scale Cas9 production. This research contributes valuable insights into optimizing E. coli strains and culture conditions for enhanced Cas9 expression, offering a step forward in the development of efficient genome editing tools and therapeutic proteins.

Speech production and perception data collection in R: A tutorial for web-based methods using speechcollectr.

This tutorial is designed for speech scientists familiar with the R programming language who wish to construct experiment interfaces in R. We begin by discussing some of the benefits of building experiment interfaces in R-including R's existing tools for speech data analysis, platform independence, suitability for web-based testing, and the fact that R is open source. We explain basic concepts of reactive programming in R, and we apply these principles by detailing the development of two sample experiments. The first of these experiments comprises a speech production task in which participants are asked to read words with different emotions. The second sample experiment involves a speech perception task, in which participants listen to recorded speech and identify the emotion the talker expressed with forced-choice questions and confidence ratings. Throughout this tutorial, we introduce the new R package speechcollectr, which provides functions uniquely suited to web-based speech data collection. The package streamlines the code required for speech experiments by providing functions for common tasks like documenting participant consent, collecting participant demographic information, recording audio, checking the adequacy of a participant's microphone or headphones, and presenting audio stimuli. Finally, we describe some of the difficulties of remote speech data collection, along with the solutions we have incorporated into speechcollectr to meet these challenges.

Desmosomes at a glance.

Desmosomes are relatives of ancient cadherin-based junctions, which emerged late in evolution to ensure the structural integrity of vertebrate tissues by coupling the intermediate filament cytoskeleton to cell-cell junctions. Their ability to dynamically counter the contractile forces generated by actin-associated adherens junctions is particularly important in tissues under high mechanical stress, such as the skin and heart. Much more than the simple cellular 'spot welds' depicted in textbooks, desmosomes are in fact dynamic structures that can sense and respond to changes in their mechanical environment and external stressors like ultraviolet light and pathogens. These environmental signals are transmitted intracellularly via desmosome-dependent mechanochemical pathways that drive the physiological processes of morphogenesis and differentiation. This Cell Science at a Glance article and the accompanying poster review desmosome structure and assembly, highlight recent insights into how desmosomes integrate chemical and mechanical signaling in the epidermis, and discuss desmosomes as targets in human disease.

Making Choices: A Multi-institutional, Longitudinal Cohort Study Assessing Changes in Treatment Outcome Valuation for Low-Risk Thyroid Cancer.

OBJECTIVE: To evaluate the relative importance of treatment outcomes to patients with low-risk thyroid cancer (TC). SUMMARY BACKGROUND DATA: Overuse of total thyroidectomy (TT) for low-risk TC is common. Emotions from a cancer diagnosis may lead patients to choose TT resulting in outcomes that do not align with their preferences. METHODS: Adults with clinically low-risk TC enrolled in a prospective, multi-institutional, longitudinal cohort study from 11/2019-6/2021. Participants rated treatment outcomes at the time of their surgical decision and again 9 months later by allocating 100 points amongst 10 outcomes. T-tests and Hotelling's T 2 statistic compared outcome valuation within and between subjects based on chosen extent of surgery (TT vs. lobectomy). RESULTS: Of 177 eligible patients, 125 participated (70.6% response) and 114 completed the 9-month follow-up (91.2% retention). At the time of the treatment decision, patients choosing TT valued the risk of recurrence more than those choosing lobectomy and the need to take thyroid hormone less ( P <0.05). At repeat valuation, all patients assigned fewer points to cancer being removed and the impact of treatment on their voice, and more points to energy levels ( P <0.05). The importance of the risk of recurrence increased for those who chose lobectomy and decreased for those choosing TT ( P <0.05). CONCLUSION: The relative importance of treatment outcomes changes for patients with low-risk TC once the outcome has been experienced to favor quality of life over emotion-related outcomes. Surgeons can use this information to discuss the potential for asthenia or changes in energy levels associated with total thyroidectomy.

Do biological control agents adapt to local pest genotypes? A multiyear test across geographic scales.

Parasite local adaptation has been a major focus of (co)evolutionary research on host-parasite interactions. Studies of wild host-parasite systems frequently find that parasites paired with local, sympatric host genotypes perform better than parasites paired with allopatric host genotypes. In contrast, there are few such tests in biological control systems to establish whether biological control parasites commonly perform better on sympatric pest genotypes. This knowledge gap prevents the optimal design of biological control programs: strong local adaptation could argue for the use of sympatric parasites to achieve consistent pest control. To address this gap, we tested for local adaptation of the biological control bacterium Pasteuria penetrans to the root-knot nematode Meloidogyne arenaria, a global threat to a wide range of crops. We measured the probability and intensity of P. penetrans infection on sympatric and allopatric M. arenaria over the course of 4 years. Our design accounted for variation in adaptation across scales by conducting tests within and across fields, and we isolated the signature of parasite adaptation by comparing parasites collected over the course of the growing season. Our results are largely inconsistent with local adaptation of P. penetrans to M. arenaria: in 3 of 4 years, parasites performed similarly well in sympatric and allopatric combinations. In 1 year, however, infection probability was 28% higher for parasites paired with hosts from their sympatric plot, relative to parasites paired with hosts from other plots within the same field. These mixed results argue for population genetic data to characterize the scale of gene flow and genetic divergence in this system. Overall, our findings do not provide strong support for using P. penetrans from local fields to enhance biological control of Meloidogyne.

Longitudinal changes in depression and anxiety during the COVID-19 pandemic and the impact of COVID-related factors.

OBJECTIVE: This study is an investigation of five specific COVID-related stressors and their longitudinal impact on adult depression and anxiety. METHOD: A total of 592 adults comprised the initial sample at Time 1 in April/May 2020. Follow-ups were conducted about a month later, again in March 2021 and then in March 2022. RESULTS: Applied linear mixed effect models showed a significant decrease in mean depression scores and anxiety scores from Time 1 to both Times 3 and 4. Neither change over time in anxiety or depression were found to be related to COVID diagnosis, COVID hospitalization, or COVID death. Self-quarantine was related to changes over time in both depression and anxiety, and household quarantine was related to changes over time in depression. CONCLUSION: While the fallout of the pandemic continues, it is important to understand how these factors may be affecting mental health to better understand where intervention is necessary.

Therapeutic Singing and Semi-Occluded Vocal Tract Exercises for Individuals with Parkinson's Disease: A Randomized Controlled Trial of a Single Session Intervention.

Individuals with Parkinson's disease (PD) experience speech and voice-related symptoms that diminish communication and quality of life. Semi-occluded vocal tract (SOVT) exercises are targeted interventions that, when combined with the positive psychosocial benefits of therapeutic group singing (TGS), may affect outcomes. The purpose of this study was to explore the effectiveness of SOVT exercises, specifically straw phonation combined with TGS, to improve voice quality and mood for individuals with PD. We used a true experimental pretest-posttest between-subjects design (i.e., randomized controlled trial) facilitated by a board-certified music therapist. All participants (N = 27) were randomly assigned to one of three groups (a) straw phonation combined with TGS (SP + TGS, n = 10), (b) TGS (n = 10), and (c) speaking-only control group (n = 7). Participants completed voice recordings for acoustic measures and the Visual Analogue Mood Scale for mood analysis before and after a 30-min intervention. The results demonstrated significant improvement in voice quality evidenced by decreasing Acoustic Voice Quality Index scores following a single session for both SP + TGS and TGS intervention groups when compared to the control. Happiness scores improved in the experimental groups when compared to control. Although not statistically significant, participants in the experimental groups (SP + TGS, TGS) demonstrated better mean mood scores on happiness, anxiety, and angry when compared to control, indicating a positive psychological response to the singing interventions. Overall, this study indicated the effectiveness of SP + TGS and TGS as promising therapeutic interventions for voice quality and mood in individuals with PD.

The Knowledge Translation of Early Cerebral Palsy (KiTE CP) Study: Implementing Screening Among a High-Risk Prospective Cohort of Australian Infants.

OBJECTIVE: To describe the implementation of the international guidelines for the early diagnosis of cerebral palsy (CP) and engagement in the screening process in an Australian cohort of infants with neonatal risk factors for CP. STUDY DESIGN: Prospective cohort study of infants with neonatal risk factors recruited at <6 months corrected age from 11 sites in the states of Victoria, New South Wales, and Queensland, Australia. First, we implemented a multimodal knowledge translation strategy including barrier identification, technology integration, and special interest groups. Screening was implemented as follows: infants with clinical indications for neuroimaging underwent magnetic resonance imaging and/or cranial ultrasound. The Prechtl General Movements Assessment (GMA) was recorded clinically or using an app (Baby Moves). Infants with absent or abnormal fidgety movements on GMA videos were offered further assessment using the Hammersmith Infant Neurological Examination (HINE). Infants with atypical findings on 2/3 assessments met criteria for high risk of CP. RESULTS: Of the 597 infants (56% male) recruited, 95% (n = 565) received neuroimaging, 90% (n = 537) had scorable GMA videos (2% unscorable/8% no video), and 25% (n = 149) HINE. Overall, 19% of the cohort (n = 114/597) met criteria for high risk of CP, 57% (340/597) had at least 2 normal assessments (of neuroimaging, GMA or HINE), and 24% (n = 143/597) had insufficient assessments. CONCLUSIONS: Early CP screening was implemented across participating sites using a multimodal knowledge translation strategy. Although the COVID-19 pandemic affected recruitment rates, there was high engagement in the screening process. Reasons for engagement in early screening from parents and clinicians warrant further contextualization and investigation.

Are Family Factors Differentially Associated with Externalizing Symptoms Among Youth with Perinatally Acquired HIV?

Youth with perinatally-acquired HIV (PHIV) face unique psychosocial stressors. They are at risk for externalizing problems, including symptoms of oppositional defiant disorder, conduct disorder (CD), and attention-deficit/hyperactivity disorder (ADHD), as well as risk-taking behaviors, such as substance use (SU). Although family factors have been differentially associated with externalizing and SU behaviors based on youth sex in prior research, there is a dearth of literature considering these processes among youth with PHIV. Participants included 314 youth with PHIV (M = 12.88 years, SD = 3.08 years; 50.80% male; 85.30% Black or Latinx). Boys exhibited higher levels of ADHD symptoms than girls. Among boys, lower levels of consistency in discipline were associated with higher CD symptoms. Lower levels of family cohesion were associated with higher levels of SU among girls, and higher levels of CD symptoms across youth sex. Findings support the need for family-focused behavioral interventions among youth with PHIV.

Feedback Versus Compliments Versus Both in Suturing and Knot Tying Simulation: A Randomized Controlled Trial.

INTRODUCTION: Suturing is an expected skill for students graduating from health professions programs. Previous studies investigated student experience with teaching sessions utilizing constructive feedback versus compliments but did not investigate the combination of both. METHODS: In this parallel, randomized controlled trial, participants were divided into three groups: feedback (F), compliments (C), or feedback and compliments (FC). Participants received standardized instruction on simple interrupted suturing and two-handed knot-tying, and were videotaped performing this skill before and after the intervention. Performance was evaluated using a validated Objective Structured Assessment of Technical Skills (OSATS) instrument. Participants completed a preintervention and postintervention survey rating their task enjoyment and self-assessment of performance. Analysis was performed to determine differences between and within the groups using Kruskal-Wallis, Wilcoxon rank-sum, and Mann-Whitney U tests. RESULTS: A total of 31 students participated: 11 in C, 10 in F, and 10 in FC. The groups had similar preintervention OSATS scores. The F and FC groups demonstrated significant improvement in OSATS score after intervention, group C was not significantly different: F median of 11.25-19.75 points (P = 0.002); FC median of 11.75-21 points (P = 0.002); C median of 13-14 points (P = 0.2266). Between the groups FC and F both had significant performance improvement compared with C (P < 0.001 and P = 0.001 respectively). The FC group had a significantly higher rating of their enjoyment of the task on the postintervention survey compared with both the C and F groups with a median rating of 10 compared with 8 and 8 (P = 0.0052 and P = 0.0126, respectively). CONCLUSIONS: The combination of feedback and compliments was associated with improvement in performance on suturing and knot-tying similar to the feedback-only group. The FC group rated a higher level of enjoyment of the activity compared to feedback or compliments alone.

Excellent Response to Therapy Occurs for Most Patients With Thyroid Cancer Treated With Lobectomy.

INTRODUCTION: American Thyroid Association (ATA) Guidelines for Management of Thyroid Nodules and Thyroid Cancer indicate that thyroid lobectomy (TL) or total thyroidectomy (TT) are appropriate surgery for low- and intermediate-risk well-differentiated thyroid carcinoma. We sought to determine outcomes of TL or TT by ATA response to therapy (RTT) classification. METHODS: This is a single-institution retrospective cohort study of adults with unilateral suspicious or malignant thyroid nodules under 4 cm from January 2016 through December 2021. Our primary outcome was ATA RTT. RESULTS: During the study period, 118 met inclusion criteria: 37 (31%) underwent TL and 81 (69%) TT. Of the TL patients, 7 (19%) underwent completion thyroidectomy. Response to therapy (RTT) was similar with TT versus TL: excellent response 56 (69%) versus 30 (81%), indeterminate response 20 (25%) versus 5 (14%), and biochemically incomplete response 5 (6%) versus 2 (5%), P = 0.20. There were no differences between the groups for age, sex, race or ethnicity, tumor size, histologic type, or complications. Thyroidectomy (TT) was associated with multiple nodules 47% versus 22% for TL (P = 0.009), bilateral nodules 43% versus 16% (P = 0.004), central neck lymph nodes removed median 3 (interquartile range [IQR] 1-8) versus 0 (IQR 0-2) P < 0.001, lymph node metastases median 0 (IQR 0-1) versus 0 (0-0) P = 0.02. Median follow-up was 32.5 mo (IQR 17-56 mo) and was similar between the groups. CONCLUSIONS: Patients with TL for well-differentiated thyroid carcinoma without high-risk features have an RTT similar to patients undergoing TT. In this cohort, 81% of patients treated with TL have not required additional intervention.

Phables: from fragmented assemblies to high-quality bacteriophage genomes.

MOTIVATION: Microbial communities have a profound impact on both human health and various environments. Viruses infecting bacteria, known as bacteriophages or phages, play a key role in modulating bacterial communities within environments. High-quality phage genome sequences are essential for advancing our understanding of phage biology, enabling comparative genomics studies and developing phage-based diagnostic tools. Most available viral identification tools consider individual sequences to determine whether they are of viral origin. As a result of challenges in viral assembly, fragmentation of genomes can occur, and existing tools may recover incomplete genome fragments. Therefore, the identification and characterization of novel phage genomes remain a challenge, leading to the need of improved approaches for phage genome recovery. RESULTS: We introduce Phables, a new computational method to resolve phage genomes from fragmented viral metagenome assemblies. Phables identifies phage-like components in the assembly graph, models each component as a flow network, and uses graph algorithms and flow decomposition techniques to identify genomic paths. Experimental results of viral metagenomic samples obtained from different environments show that Phables recovers on average over 49% more high-quality phage genomes compared to existing viral identification tools. Furthermore, Phables can resolve variant phage genomes with over 99% average nucleotide identity, a distinction that existing tools are unable to make. AVAILABILITY AND IMPLEMENTATION: Phables is available on GitHub at https://github.com/Vini2/phables.

PP2A-B55alpha controls keratinocyte adhesion through dephosphorylation of the Desmoplakin C-terminus.

Critical for the maintenance of epidermal integrity and function are attachments between intermediate filaments (IF) and intercellular junctions called desmosomes. The desmosomal cytoplasmic plaque protein desmoplakin (DP) is essential for anchoring IF to the junction. DP-IF interactions are regulated by a phospho-regulatory motif within the DP C-terminus controlling keratinocyte intercellular adhesion. Here we identify the protein phosphatase 2A (PP2A)-B55α holoenzyme as the major serine/threonine phosphatase regulating DP's C-terminus and consequent intercellular adhesion. Using a combination of chemical and genetic approaches, we show that the PP2A-B55α holoenzyme interacts with DP at intercellular membranes in 2D- and 3D- epidermal models and human skin samples. Our experiments demonstrate that PP2A-B55α regulates the phosphorylation status of junctional DP and is required for maintaining strong desmosome-mediated intercellular adhesion. These data identify PP2A-B55α as part of a regulatory module capable of tuning intercellular adhesion strength and a candidate disease target in desmosome-related disorders of the skin and heart.

Transcriptional profiling of rare acantholytic disorders suggests common mechanisms of pathogenesis.

Darier, Hailey-Hailey, and Grover diseases are rare acantholytic skin diseases. While these diseases have different underlying causes, they share defects in cell-cell adhesion in the epidermis and desmosome organization. To better understand the underlying mechanisms leading to disease in these conditions, we performed RNA-seq on lesional skin samples from patients. The transcriptomic profiles of Darier, Hailey-Hailey, and Grover diseases were found to share a remarkable overlap, which did not extend to other common inflammatory skin diseases. Analysis of enriched pathways showed a shared increase in keratinocyte differentiation, and a decrease in cell adhesion and actin organization pathways in Darier, Hailey-Hailey, and Grover diseases. Direct comparison to atopic dermatitis and psoriasis showed that the downregulation in actin organization pathways was a unique feature in the acantholytic skin diseases. Furthermore, upstream regulator analysis suggested that a decrease in SRF/MRTF activity was responsible for the downregulation of actin organization pathways. Staining for MRTFA in lesional skin samples showed a decrease in nuclear MRTFA in patient skin compared with normal skin. These findings highlight the significant level of similarity in the transcriptome of Darier, Hailey-Hailey, and Grover diseases, and identify decreases in actin organization pathways as a unique signature present in these conditions.

The body positivity movement is not all that positive on TikTok: A content analysis of body positive TikTok videos.

This analysis examined the content of 342 body positive videos on TikTok. Videos were gathered by searching #body positivity and coded for diversity, positive body image messages, negative appearance-focused messages, other relevant themes, and contradictory messaging. Results demonstrate that body positivity videos on TikTok often portrayed young, White women with unrealistic beauty ideals. Approximately 93% of the videos embodied Western culturally based beauty ideals somewhat or to a great extent, while 32% of the videos portrayed larger bodies. Only 32.2% of the videos contained explicit positive body image messaging, and negative appearance-focused themes or objectifying content was rare. Contradictory messaging was not present. Overall, body positive videos on TikTok rarely displayed features aligned with positive body image and promoted unrealistic beauty ideals but also rarely included explicit negative appearance-focused messaging. Future research examining effects of exposure to body positivity messaging on TikTok, in comparison to other social media platforms, is warranted.

Phables: from fragmented assemblies to high-quality bacteriophage genomes.

Microbial communities influence both human health and different environments. Viruses infecting bacteria, known as bacteriophages or phages, play a key role in modulating bacterial communities within environments. High-quality phage genome sequences are essential for advancing our understanding of phage biology, enabling comparative genomics studies, and developing phage-based diagnostic tools. Most available viral identification tools consider individual sequences to determine whether they are of viral origin. As a result of the challenges in viral assembly, fragmentation of genomes can occur, leading to the need for new approaches in viral identification. Therefore, the identification and characterisation of novel phages remain a challenge. We introduce Phables, a new computational method to resolve phage genomes from fragmented viral metagenome assemblies. Phables identifies phage-like components in the assembly graph, models each component as a flow network, and uses graph algorithms and flow decomposition techniques to identify genomic paths. Experimental results of viral metagenomic samples obtained from different environments show that Phables recovers on average over 49% more high-quality phage genomes compared to existing viral identification tools. Furthermore, Phables can resolve variant phage genomes with over 99% average nucleotide identity, a distinction that existing tools are unable to make. Phables is available on GitHub at https://github.com/Vini2/phables.

Adapting CBT for youth anxiety: Flexibility, within fidelity, in different settings.

Anxiety disorders are common in youth, associated with impairments in daily functioning, and often persist into adulthood when untreated. Cognitive behavioral therapy (CBT) for youth anxiety is a well-established intervention and has been modified to fit several treatment settings. Despite decades of results supporting the efficacy of CBT, there is a large gap in access to this treatment and a need to consider how it can best be administered flexibly to increase uptake and personalization. We first discuss the core components of treatment for CBT through the lens of the Coping Cat treatment. Next, we review the empirical findings regarding adjustments made for CBT for youth anxiety delivered (a) in schools, (b) in community settings, (c) through telehealth, (d) through online computer programs, and (e) by caregivers at home. In each setting, we provide specific suggestions for how to implement CBT with flexibility while maintaining fidelity.

Effects of preharvest factors on antidiabetic potential of some foods and herbal plants.

Diabetes is a metabolic disorder with no definite treatment, but it can be controlled by changing lifestyle and diet. Consumption of high-fiber and nutrient-rich foods including vegetables have been shown to reduce risks of obesity and Type II Diabetes Mellitus (T2DM). Also, many herbal plants have been associated with reduced risks of T2DM because of their composition of secondary metabolites. Antioxidant activities of some secondary metabolites have potent inhibitory effects against inflammation linked with insulin resistance and oxidative stress. More than 800 known medicinal plants are used to control diabetes and its relevant complications. However, variations in preharvest factors including plant genotype, growing medium properties, climatic factors, and management practices can influence plant growth and their accumulation of phytochemicals with health-promoting properties. However, the effects of these preharvest factors on the antidiabetic properties of plant secondary metabolites are neither explicit nor easily accessible in the literature. Therefore, this review aims to document recent studies that reported on under-exploited medicinal plants with antidiabetic properties. We reviewed several important preharvest factors that can potentially affect the synthesis of phytoconstituents which possess antidiabetic properties. This review will help identify gaps for future research in phytomedicine and functional foods.

Factors Associated With Persistent Post-transplant Hyperparathyroidism After Index Renal Transplantation.

INTRODUCTION: Secondary hyperparathyroidism (SHP) is common in end-stage renal disease and may progress to persistent post-transplant hyperparathyroidism (PTHP) following renal transplantation (RT). We sought to describe the frequency and determine factors associated with the incidence of PTHP for patients undergoing RT at a single institution that restricts RT for patients with uncontrolled SHP with a parathyroid hormone (PTH) of >800pg/mL at time of initial transplant evaluation. METHODS: We conducted a single-institution retrospective study of adults undergoing index RT from 2012 to 2020 who had a calcium and PTH level within 12 mo prior to RT and at least 6 mo following RT. PTHP was defined as calcium of >10 mg/dL with an elevated PTH > 88pg/mL at six or more months following RT. Univariate analysis and multivariable logistic regression were performed for factors associated with developing PTHP. RESULTS: We identified 1110 patients with RT, 65 were excluded for prior RT, 549 did not have a pre-RT and post-RT calcium, and PTH laboratories for inclusion, yielding 496 for analysis. Following RT, 39 patients (7.9%) developed PTHP, compared to those who did not develop PTHP; these patients had significantly higher pre-RT PTH, pre-RT calcium, and frequency of calcimimetic therapy. In multivariable logistic regression factors significantly associated with PTHP were pre-RT calcium of more than 10 mg/dL with an odds ratio (OR) of 3.57 (95% confidence interval [CI] 1.52-8.39, P = 0.003) and pre-RT calcimimetic therapy with an OR 1.30 (95% CI 1.06-2.85, P = 0.041). Compared with patients who had a pre-RT PTH of less than 200 pg/mL, a PTH of 200-399 pg/mL increased risk of PTHP with an OR of 4.52 (95% CI 1.95-21.5, P = 0.048) and a PTH of > 400 pg/mL increased risk of PTHP with an OR of 7.17 (95% CI 1.47-34.9, P = 0.015). In this cohort, 11 patients (28.2%) with PTHP underwent parathyroidectomy (PTx) at a mean of 1.4 y post-RT (standard deviation 0.87). CONCLUSIONS: For patients required to have a PTH < 800pg/mL for initial transplant candidacy, the subsequent incidence of PTHP is relatively low at 7.9%. Risk factors for PTHP include higher pre-RT calcium and PTH levels and pre-RT calcimimetic therapy. PTx remains underused in the treatment of PTHP. Further study is warranted to determine the optimal PTH cutoff for transplant candidacy and recommendation for PTx in patients requiring calcimimetic therapy for SHP.

Cross-Suturing is Effective for Teaching Suturing Skills: A Randomized, Controlled Trial.

INTRODUCTION: Basic suturing is a skill expected from graduating medical students. A proposed concept to increase suturing competency is to integrate art by mixing cross-stitching with suturing. We hypothesize that students trained with "cross-suturing" would improve suturing performance. METHODS: We performed a randomized controlled trial of preclinical medical students using an art-based cross-stitching method intervention compared with conventional suturing. Both groups were provided with an introductory suturing video. Assessment of simple interrupted suturing were conducted preintervention and postintervention, and at 2-wk follow-up with a video review by blinded expert raters using the American College of Surgeons basic suturing and knot tying performance rating tool. Students completed a self-assessment of proficiency, confidence, and anxiety. Statistical analysis was performed using unpaired t-tests. RESULTS: A total of 16 preclinical medical students participated. Self-assessment and objective suturing performance were comparable in the preintervention measurements. The intervention group showed significant improvement compared to the control group with median (interquartile range) self-assessment scores 9 (8.5-9) compared with 6.5 (6-7.5) (P < 0.01) and objective performance scores of 25.25 (22.75-27) compared with 16.5 (14.5-18.5) (P < 0.01). The intervention group showed retained skills at the 2-wk follow up with no differences in self-assessment or objective suturing scores immediately postintervention compared with two-wk follow-up with self-assessment scores of 9 (8.5-9) versus 9 (8-9) at 2 wk (P = 0.16) and objective performance score of 25.25 (22.75-27) versus 24.75 (23.5-26.5) at 2 wk (P = 0.29). CONCLUSIONS: The cross-suturing intervention improved suturing skills in this cohort. This low-cost approach to medical student surgical education should be explored on a larger scale.