Background Custom genes have become a common resource in recombinant biology over the last 20 years due to the plummeting cost of DNA synthesis. These genes are often “optimized” to non-native sequences for overexpression in a non-native host by substituting synonymous codons within the coding DNA sequence (CDS). A handful of studies have compared native and optimized CDSs, reporting different levels of soluble product due to the accumulation of misfolded aggregates, variable activity of enzymes, and (at least one report of) a change in substrate specificity. No study, to the best of our knowledge, has performed a practical comparison of CDSs generated from different codon optimization algorithms or reported the corresponding protein yields. Results In our efforts to understand what factors constitute an optimized CDS, we identified that there is little consensus among codon-optimization algorithms, a roughly equivalent chance that an algorithm-optimized CDS will increase or diminish recombinant yields as compared to the native DNA, a near ubiquitous use of a codon database that was last updated in 2007, and a high variability of output CDSs by some algorithms. We present a case study, using KRas4B, to demonstrate that a median codon frequency may be a better predictor of soluble yields than the more commonly utilized CAI metric. Conclusions We present a method for visualizing, analyzing, and comparing algorithm-optimized DNA sequences for recombinant protein expression. We encourage researchers to consider if DNA optimization is right for their experiments, and work towards improving the reproducibility of published recombinant work by publishing non-native CDSs.

Adult Refsum disease (ARD) is a rare peroxisomal biogenesis disorder inherited in an autosomal recessive fashion and is often characterized by retinitis pigmentosa, cerebellar ataxia, and polyneuropathy. Many patients with ARD require diet modification, psychosocial support, and various specialist visits to manage their symptoms. In this study, we explored the quality of life in individuals with ARD by analyzing retrospective survey data collected by the Coordination of Rare Diseases at Sanford (CoRDS) Registry and Global Defeat Adult Refsum Everywhere (DARE) Foundation. Statistical tests used were frequencies, mean, and median. There were 32 respondents, ranging between 11 and 32 responses for each question. The mean age at diagnosis was 35.5 ± 14.5 years (range 6–64) with 36.4% male and 63.6% female respondents. The average age for retinitis pigmentosa diagnosis was 22.8 ± 15.7 years (range 2–61). Dieticians were the most frequently seen (41.7%) for management of low-phytanic-acid diets. Most participants exercise at least once per week (92.5%). Depression symptoms were reported in 86.2% of the participants. Early diagnosis of ARD is important for managing symptoms and preventing progression of visual impairment due to phytanic acid buildup. Interdisciplinary approach should be used for patients to address physical and psychosocial impairments of ARD.

Patient: Female, 31-year-old Final Diagnosis: Central diabetes insipidus Symptoms: Polydipsia • polyuria Medication: — Clinical Procedure: — Specialty: Endocrinology and Metabolic Objective: Unusual clinical course Background: Nephrogenic diabetes insipidus is a well-known adverse effect of lithium use. Albeit rare, there have also been documented cases of central diabetes insipidus (CDI) associated with lithium use. Case Report: A 31-year-old woman with a past medical history of bipolar disorder, managed with lithium 300 mg by mouth every day for 3 years, was assessed for a 1-year history of polyuria with accompanying polydipsia. During her initial hospital stay, her estimated urine output was more than 4 L per day. Initial labs showed elevated serum sodium (149 mmol/L; reference range 135–145), elevated serum osmolality (304 mOsm/kg; reference range 275–295), urine osmolality of 99 mOsm/kg (reference range 50–1200), and urine specific gravity (1.005; reference range 1.005–1.030). Lithium was at a subtherapeutic level of 0.05 mEq/L (reference range 0.6–1.2). Magnetic resonance imaging of the brain revealed no abnormalities of the pituitary gland. Two different occasions of desmopressin administration resulted in >50% increase in urine osmolality, confirming the diagnosis of CDI. Common causes of CDI, including trauma, tumors, and familial CDI, were ruled out and chronic lithium use was determined as the most probable cause for the patient’s CDI. Conclusions: CDI in the background of chronic lithium use is rarely reported. We present this case to consider CDI as a differential diagnosis when evaluating polyuria and hypernatremia in patients with long-term lithium use. These presentations warrant the consideration of both types of diabetes insipidus in the differential diagnoses.

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INTRODUCTION Point‐of‐care ultrasonography (POCUS) is commonly used in many modalities of medicine. However, there is a lack of standardized protocol for integrating POCUS into preclinical medical education. Previous literature has detailed the benefits of POCUS in clinical diagnoses and reasoning, but many medical students still lack exposure to POCUS. At California University of Science and Medicine (CUSM), medical students will be exposed to POCUS in their preclinical years. We aim to compare the confidence levels and ultrasound‐performance skills of medical students with and without prior videographic ultrasound exposure. Hypothesis Prior videographic ultrasound exposure will improve the confidence and ultrasound‐performance skills of medical students during a live ultrasound workshop compared to those without videographic exposure. Methods Participants will be divided into two groups. One group will watch a 5–10‐minute procedural video about ultrasound‐guided peripheral intravenous (IV) access prior to ultrasound training, while the other group will be ultrasound‐naive prior to ultrasound training. Ultrasound training will be led by three other medical students who are trained and approved by ultrasound physicians. After demonstrations, participants will practice ultrasound‐guided IV access on a practice pad. Instructors will grade students on the spot on their ability to perform ultrasound‐guided IV access correctly. The parameters measured will be proper positioning of the ultrasound probe, insertion of the needle, ultrasound probe movement, puncturing of the vein, and overall technique. The two study groups will then take surveys on their perceived performance and overall confidence levels. Results Results from participants will be scored using two measures. Firstly, their self‐reflection surveys will measure their level of confidence and perceived ultrasound‐performance skills. Secondly, on‐the‐spot grading by instructors will provide information on participants’ actual ultrasound‐performance skills. A standardized grading scheme will ensure fairness among different instructors and participants. Conclusion Comparison of the effectiveness of an additional videographic ultrasound component prior to live demonstration will be elucidated. This study will help create elements within existing ultrasound curriculae that will enhance the confidence and ultrasound‐performance skills of preclinical medical students.