The Platysma Contraction Pattern in Healthy Adults: A Vector Analysis Study.

BACKGROUND: The platysma muscle's role in lower face dynamics is complex. Multiple insertion points to soft-tissue structures at various levels in the lower face create a multifaceted contraction pattern. To avoid adverse effects in cosmetic procedures when targeting the platysma, its anatomy and physiology must be understood. Clinical observations hint at a bidirectional contraction pattern. METHODS: Eighteen healthy volunteers (13 women and five men) with a mean age of 44.2 ± 10.1 years were enrolled. Skin displacement vector analysis was used on maximal platysma contraction to characterize and calculate the movement of the neck and lower face skin. RESULTS: In all of the participants, a bidirectional movement of the skin was observed: the skin of the lower face and inferior to the jawline moved caudally, whereas the skin of the lower neck moved cephalad. Both movements converged at a line situated at 54% ± 10% and 55% ± 8% of the length between the clavicle and the inferior base of the ear lobe in men and women, respectively ( P = 0.70). CONCLUSIONS: The platysma is a bidirectional muscle with a line of convergence. Whereas the superior portion acts as lip depressor, the lower portion elevates the skin of the upper chest and lower neck. This transition can explain some of the clinically observed adverse effects of neuromodulation of the neck area. It can potentially direct neuromodulation injections to focus above the convergence line to better address lower face descent.

Chemoenzymatic Synthesis of 3'-Deoxy-3',4'-didehydro-cytidine triphosphate (ddhCTP).

3'-Deoxy-3',4'-didehydro-cytidine triphosphate (ddhCTP) is a novel antiviral molecule produced by the enzyme viperin during the early stages of the innate immune response. ddhCTP has been shown to act as a chain terminator of flavivirus RNA-dependent RNA polymerases. To date, synthesis of ddhCTP requires complicated synthetic protocols or isolation of the enzyme viperin to catalyze the production of ddhCTP from CTP. Recombinant viperin approaches preclude the production of highly pure ddhCTP (free of contaminants such as CTP), whereas the chemical synthesis involves techniques or equipment not readily available to most laboratories. Herein, we describe the chemoenzymatic synthesis of ddhCTP, starting from commercially available ddhC. We utilize these methods to produce milligram quantities of ddhCTP, ddhCDP, and ddhCMP. Using purified semisynthetic ddhCTP and fully synthetic ddhCTP, we also show ddhCTP does not inhibit NAD+-dependent enzymes such as glyceraldehyde 3-phosphate dehydrogenase, malate dehydrogenase, or lactate dehydrogenase, contrary to a recent report.

SARS-CoV-2 multi-antigen protein microarray for detailed characterization of antibody responses in COVID-19 patients.

Antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) target multiple epitopes on different domains of the spike protein, and other SARS-CoV-2 proteins. We developed a SARS-CoV-2 multi-antigen protein microarray with the nucleocapsid, spike and its domains (S1, S2), and variants with single (D614G, E484K, N501Y) or double substitutions (N501Y/Deletion69/70), allowing a more detailed high-throughput analysis of the antibody repertoire following infection. The assay was demonstrated to be reliable and comparable to ELISA. We analyzed antibodies from 18 COVID-19 patients and 12 recovered convalescent donors. The S IgG level was higher than N IgG in most of the COVID-19 patients, and the receptor-binding domain of S1 showed high reactivity, but no antibodies were detected against the heptad repeat domain 2 of S2. Furthermore, antibodies were detected against S variants with single and double substitutions in COVID-19 patients who were infected with SARS-CoV-2 early in the pandemic. Here we demonstrated that the SARS-CoV-2 multi-antigen protein microarray is a powerful tool for detailed characterization of antibody responses, with potential utility in understanding the disease progress and assessing current vaccines and therapies against evolving SARS-CoV-2.

Intravenous Lidocaine in Chronic Neuropathic Pain: A Systematic Review.

OBJECTIVES: A systematic review of original research articles was conducted to evaluate the safety and efficacy of lidocaine infusion in the treatment of adult patients with chronic neuropathic pain. MATERIALS AND METHODS: Original research from 1970 to September 2021 describing adult patients with chronic neuropathic pain receiving at least 1 dose of intravenous lidocaine was included. Extracted data included study design, sample size, patient demographics and comorbidities, etiology and duration of pain, pain intensity scores, time to pain resolution, lidocaine dose and administration frequency, lidocaine serum concentration, and adverse events. Each study was evaluated for level of evidence using the 2017 American Association of Neurology classification system. RESULTS: Twenty-seven studies evaluating lidocaine infusion treatment in chronic neuropathic pain met inclusion criteria. One class I study was identified for patients with neuropathic pain due to spinal cord injury . Two Class II studies were identified, one describing neuropathic pain due to peripheral nerve injury and another due to diabetic neuropathy. Across all studies, study design, participants, and experimental interventions were heterogenous with wide variation. DISCUSSION: This qualitative review found insufficient, heterogenous evidence and therefore no recommendation can be made for lidocaine infusion treatment in patients with chronic neuropathic pain due to spinal cord injury, peripheral nerve injury, diabetic neuropathy, postherpetic neuralgia, or complex regional pain syndrome type II. Larger randomized, double-blind, placebo-controlled studies are required to further establish the efficacy of lidocaine infusion in patients with these etiologies of chronic neuropathic pain.

Serum electrolyte concentrations and skeletal muscle excitability in vivo.

OBJECTIVE: Multi-fibre muscle velocity recovery cycle (MVRC) assessment is a well-tolerated method of evaluating sarcolemmal excitability in vivo that shows promise as a research tool and biomarker. MVRC parameters correlate with venous electrolyte concentrations in myopathies. We sought to determine the nature of any such relationships in individuals without muscle disease. METHODS: Tibialis anterior MVRCs were recorded and electrolyte concentrations measured from two groups of healthy volunteers. After studying a single measure cohort (n = 65, one recording/person), we studied a repeated measures cohort (n = 4, eight recordings/person) to better study intra-individual relationships using repeated measures correlation (rmcorr). RESULTS: In the single measure cohort, no significant correlations were present between MVRC parameters and electrolyte levels after accounting for age. In the repeated measures cohort, the relative refractory period (P < 0.01) and stimulus frequency measures (P < 0.01) correlated positively with potassium levels. Multiple late supernormality group measures correlated negatively with bicarbonate levels (P < 0.01). CONCLUSIONS: MVRC measures that vary with the resting muscle membrane potential correlate with venous potassium concentrations, as in myopathies. Late supernormality measures correlate with bicarbonate levels. SIGNIFICANCE: Determination of serum electrolyte levels may inform the interpretation of MVRC study results if variation in concentrations is anticipated to be significant.

Single-Dilution COVID-19 Antibody Test with Qualitative and Quantitative Readouts.

The coronavirus disease 2019 (COVID-19) global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to place an immense burden on societies and health care systems. A key component of COVID-19 control efforts is serological testing to determine the community prevalence of SARS-CoV-2 exposure and quantify individual immune responses to prior SARS-CoV-2 infection or vaccination. Here, we describe a laboratory-developed antibody test that uses readily available research-grade reagents to detect SARS-CoV-2 exposure in patient blood samples with high sensitivity and specificity. We further show that this sensitive test affords the estimation of viral spike-specific IgG titers from a single sample measurement, thereby providing a simple and scalable method to measure the strength of an individual's immune response. The accuracy, adaptability, and cost-effectiveness of this test make it an excellent option for clinical deployment in the ongoing COVID-19 pandemic.IMPORTANCE Serological surveillance has become an important public health tool during the COVID-19 pandemic. Detection of protective antibodies and seroconversion after SARS-CoV-2 infection or vaccination can help guide patient care plans and public health policies. Serology tests can detect antibodies against past infections; consequently, they can help overcome the shortcomings of molecular tests, which can detect only active infections. This is important, especially when considering that many COVID-19 patients are asymptomatic. In this study, we describe an enzyme-linked immunosorbent assay (ELISA)-based qualitative and quantitative serology test developed to measure IgG and IgA antibodies against the SARS-CoV-2 spike glycoprotein. The test can be deployed using commonly available laboratory reagents and equipment and displays high specificity and sensitivity. Furthermore, we demonstrate that IgG titers in patient samples can be estimated from a single measurement, enabling the assay's use in high-throughput clinical environments.

Characterization of the SARS-CoV-2 S Protein: Biophysical, Biochemical, Structural, and Antigenic Analysis.

Coronavirus disease 2019 (COVID-19) is a global health crisis caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and there is a critical need to produce large quantities of high-quality SARS-CoV-2 Spike (S) protein for use in both clinical and basic science settings. To address this need, we have evaluated the expression and purification of two previously reported S protein constructs in Expi293F and ExpiCHO-S cells, two different cell lines selected for increased protein expression. We show that ExpiCHO-S cells produce enhanced yields of both SARS-CoV-2 S proteins. Biochemical, biophysical, and structural (cryo-EM) characterizations of the SARS-CoV-2 S proteins produced in both cell lines demonstrate that the reported purification strategy yields high-quality S protein (nonaggregated, uniform material with appropriate biochemical and biophysical properties), and analysis of 20 deposited S protein cryo-EM structures reveals conformation plasticity in the region composed of amino acids 614-642 and 828-854. Importantly, we show that multiple preparations of these two recombinant S proteins from either cell line exhibit identical behavior in two different serology assays. We also evaluate the specificity of S protein-mediated host cell binding by examining interactions with proposed binding partners in the human secretome and report no novel binding partners and notably fail to validate the Spike:CD147 interaction. In addition, the antigenicity of these proteins is demonstrated by standard ELISAs and in a flexible protein microarray format. Collectively, we establish an array of metrics for ensuring the production of high-quality S protein to support clinical, biological, biochemical, structural, and mechanistic studies to combat the global pandemic caused by SARS-CoV-2.

Comparison of Skin Antiseptic Agents and the Role of 0.01% Hypochlorous Acid.

BACKGROUND: Hypochlorous acid (HA) has both anti-microbial and wound-healing properties with a growing role for utilization in pre-procedural care on the face. OBJECTIVES: The authors sought to compare the antiseptic property of 0.01% HA solution, 5% povidone iodine (PI), 4% chlorhexidine gluconate (CHG), and 70% isopropyl alcohol (IPA) antiseptic on facial skin. METHODS: This was a prospective single-center clinical trial. RESULTS: A total of 21 participants were recruited. Bacterial growth was seen in CHG (10%), IPA (71%), PI (81%), and HA (95%) of specimens (P < 0.001). CHG had less growth compared with HA (P = <0.001), IPA (P = <0.001), and PI (P = <0.001). No difference in bacterial growth was noted between HA and IPA (P = 0.063) or HA and PI (P = 0.25). Significant differences in mono-microbial and poly-microbial growth were seen between HA and IPA (P = 0.046) and HA and CHG (P = <0.001). Staphylococcus epidermidis grew less frequently in CHG (10%), followed by IPA (29%), PI (71%), and HA (71%). Staphylococcus capitis grew less frequently in CHG (0%), followed by PI (14%), HA (24%), and IPA (29%). CONCLUSIONS: CHG reduced the bacterial growth compared with HA, PI, and IPA. However, HA, PI, and IPA had insignificant differences in bactericidal effects. Our study provides a supporting role of HA to be considered as an antiseptic.

Development, clinical translation, and utility of a COVID-19 antibody test with qualitative and quantitative readouts.

The COVID-19 global pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to place an immense burden on societies and healthcare systems. A key component of COVID-19 control efforts is serologic testing to determine the community prevalence of SARS-CoV-2 exposure and quantify individual immune responses to prior infection or vaccination. Here, we describe a laboratory-developed antibody test that uses readily available research-grade reagents to detect SARS-CoV-2 exposure in patient blood samples with high sensitivity and specificity. We further show that this test affords the estimation of viral spike-specific IgG titers from a single sample measurement, thereby providing a simple and scalable method to measure the strength of an individual's immune response. The accuracy, adaptability, and cost-effectiveness of this test makes it an excellent option for clinical deployment in the ongoing COVID-19 pandemic.

Neuropathy in sporadic inclusion body myositis: A multi-modality neurophysiological study.

OBJECTIVE: Sporadic inclusion body myositis (sIBM) has been associated with neuropathy. This study employs nerve excitability studies to re-examine this association and attempt to understand underlying pathophysiological mechanisms. METHODS: Twenty patients with sIBM underwent median nerve motor and sensory excitability studies, clinical assessments, conventional nerve conduction testing (NCS) and quantitative thermal threshold studies. These results were compared to established normal controls, or results from a normal cohort of older control individuals. RESULTS: Seven sIBM patients (35%) demonstrated abnormalities in conventional NCS, with ten patients (50%) demonstrating abnormalities in thermal thresholds. Median nerve motor and sensory excitability differed significantly in sIBM patients when compared to normal controls. None of these neurophysiological markers correlated significantly with clinical markers of sIBM severity. CONCLUSION: A concurrent neuropathy exists in a significant proportion of sIBM patients, with nerve excitability studies revealing changes possibly consistent with axolemmal depolarization or concurrent neuronal adaptation to myopathy. Neuropathy in sIBM does not correlate with muscle disease severity and may reflect a differing tissue response to a common pathogenic factor. SIGNIFICANCE: This study affirms the presence of a concurrent neuropathy in a large proportion of sIBM patients that appears independent of the severity of myopathy.

Shared Mental Models Among Clinical Competency Committees in the Context of Time-Variable, Competency-Based Advancement to Residency.

PURPOSE: To evaluate response process validity evidence for clinical competency committee (CCC) assessments of first-year residents on a subset of General Pediatrics Entrustable Professional Activities (EPAs) and milestones in the context of a national pilot of competency-based, time-variable (CBTV) advancement from undergraduate to graduate medical education. METHOD: Assessments of 2 EPAs and 8 milestones made by the trainees' actual CCCs and 2 different blinded "virtual" CCCs for 48 first-year pediatrics residents at 4 residency programs between 2016 and 2018 were compared. Residents had 3 different training paths from medical school to residency: time-variable graduation at the same institution as their residency, time-fixed graduation at the same institution, or time-fixed graduation from a different institution. Assessments were compared using ordinal mixed-effects models. RESULTS: Actual CCCs assigned residents higher scores than virtual CCCs on milestones and one EPA's supervision levels. Residents who graduated from a different institution than their residency received lower milestone ratings than either group from the same institution; CBTV residents received higher ratings on one milestone (ICS4) and similar ratings on all others compared with non-CBTV residents who completed medical school at the same institution. CONCLUSIONS: First-year residents who graduated from CBTV medical school programs were assessed as having the same level of competence as residents who graduated from traditional medical school programs, but response process evidence suggests that members of CCCs may also draw on undocumented personal knowledge of the learner to draw conclusions about resident competence.

Characterization of the SARS-CoV-2 S Protein: Biophysical, Biochemical, Structural, and Antigenic Analysis.

Coronavirus disease 2019 ( COVID-19 ) is a global health crisis caused by the novel severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ), and there is a critical need to produce large quantities of high-quality SARS-CoV-2 Spike ( S ) protein for use in both clinical and basic science settings. To address this need, we have evaluated the expression and purification of two previously reported S protein constructs in Expi293F ™ and ExpiCHO-S ™ cells, two different cell lines selected for increased expression of secreted glycoproteins. We show that ExpiCHO-S ™ cells produce enhanced yields of both SARS-CoV-2 S proteins. Biochemical, biophysical, and structural ( cryo-EM ) characterization of the SARS-CoV-2 S proteins produced in both cell lines demonstrate that the reported purification strategy yields high quality S protein (non-aggregated, uniform material with appropriate biochemical and biophysical properties). Importantly, we show that multiple preparations of these two recombinant S proteins from either cell line exhibit identical behavior in two different serology assays. We also evaluate the specificity of S protein-mediated host cell binding by examining interactions with proposed binding partners in the human secretome. In addition, the antigenicity of these proteins is demonstrated by standard ELISAs, and in a flexible protein microarray format. Collectively, we establish an array of metrics for ensuring the production of high-quality S protein to support clinical, biological, biochemical, structural and mechanistic studies to combat the global pandemic caused by SARS-CoV-2.

Sarcolemmal depolarization in sporadic inclusion body myositis assessed with muscle velocity recovery cycles.

OBJECTIVE: To study patients with sporadic inclusion body myositis (sIBM) with muscle velocity recovery cycles (MVRC) to assess muscle membrane excitability, pathophysiological mechanisms and potential biomarkers of this disorder. METHODS: MVRC were recorded from 20 individuals with sIBM from tibialis anterior (TA) and rectus femoris (RF) muscles. Excitability parameters were compared with MVRC data obtained from 22 normal controls >50 years. RESULTS: Muscle relative refractory period was prolonged in both TA (6.4 ms vs 4.4 ms, P < 0.001) and RF (7.1 ms vs 3.9 ms, P < 0.001) of sIBM affected muscle when compared to controls. Early supernormality was reduced in both TA (3.6% vs 8.8% P = 0.001) and in RF (mean 5.4% vs 13% P < 0.001). Late supernormality was only decreased significantly in sIBM affected TA (1.8% vs 3.6% P = 0.001) but not in RF. No consistent correlations between MVRC parameters and clinical markers of sIBM disease severity were found. CONCLUSION: The resting sarcolemmal muscle membrane potential of sIBM muscle is depolarized relative to that of normal controls, which may be related to intramuscular amyloid deposition in sIBM. SIGNIFICANCE: Sarcolemmal depolarization may play a role in muscle dysfunction and weakness observed in sIBM patients.

Physiological differences in sarcolemmal excitability between human muscles.

INTRODUCTION: The sarcolemmal resting membrane potential (RMP) affects muscle excitability, contractility, and force generation. However, there are limited In vivo data on the normal RMP of the human sarcolemma between muscles. We hypothesize that the in vivo RMP may differ between human muscles with different physiological roles. METHODS: Muscle velocity recovery cycles were recorded from a proximal antigravity muscle, the rectus femoris, and compared with paired recordings from a distal non-antigravity muscle, the tibialis anterior, in 34 normal individuals. RESULTS: Significant differences in muscle relative refractory period (3.55 millseconds vs 3.87 milliseconds, P = .002), early supernormality (14.22% vs 10.50%, P < .0001), and late supernormality (5.43% vs 3.50%, P < .0001) were observed. DISCUSSION: The results strongly suggest a less negative RMP in tibialis anterior vs rectus femoris and attest to intermuscle differences in normal excitability and physiology. This novel finding employing an in vivo methodology highlights the need for muscle-specific normative data in future studies.

Association of Shadowing Program for Undergraduate Premedical Students with Improvements in Understanding Medical Education and Training.

OBJECTIVE: Physician shadowing has become ubiquitous to the premedical experience. However, students without connections to a medical professional are oftentimes forced to reach out to physicians independently from a program. Subsequently, these inquiries may go unanswered as they oftentimes appear unsolicited. The primary goals in the design and development of our program were to increase access to a clinical observership experience at our academic institution utilizing resident physicians as primary supervisors. METHODS: In January 2017, the Educational Shadowing Program (ESP) was established at our institution wherein undergraduate students could shadow within the Pediatric Continuity Clinic (PCC) staffed by pediatric resident physicians. ESP undergraduates shadowed the residents as they performed their history taking and physical exams and as they presented their patients to the attending physicians. Between patient encounters, the students assisted the residents in their administrative work which was completed as needed. ESP students were surveyed at their first orientation meeting and during the final case conference. RESULTS: The pre-participation survey showed that none of the student participants strongly agreed to having a good understanding of what the job of a resident physician entails. By the end of their 30 weeks, the proportion of participants with a strongly perceived understanding increased significantly. The proportion of student respondents that strongly agreed with their understanding of the physician-patient interaction also improved significantly over the study period, from 33% to 78%. Seventy-two percent of the residents surveyed agreed or strongly agreed that they enjoyed having the undergraduates in the clinic, affirming the positive effects of the program on the resident physicians. Forty-five percent of residents agreed or strongly agreed that the undergraduates improved their workflow in the clinic. CONCLUSION: This study demonstrates that establishing an undergraduate shadowing program in a busy academic pediatric clinic that involves resident physicians can be an overall positive experience for all participants. Fostering premedical student interest in pediatric care and primary care can possibly lead to more physician commitment to these fields, potentially helping to alleviate impending physicians in these specialties.

Effectiveness of Electroconvulsive Therapy in Patients With Major Depressive Disorder and Comorbid Borderline Personality Disorder.

OBJECTIVE: Previous research suggests that electroconvulsive therapy (ECT)-the criterion standard for the treatment of severe depression-is not as effective when the patient has comorbid borderline personality disorder (BPD). The ECT outcomes of patients with and without BPD were compared in a retrospective chart review to test this claim. METHODS: We enrolled 137 patients with a diagnosis of major depressive disorder who completed the McLean Screening Instrument for Borderline Personality Disorder. Twenty-nine patients had positive screening scores for BPD. The difference in Patient Health Questionnaire (PHQ-9) scores before and after ECT was compared between patients with and without BPD. Follow-up PHQ-9 scores determined after treatment were collected and analyzed. RESULTS: Electroconvulsive therapy equally improved symptoms of depression as measured by PHQ-9 score in both patients who screened positive and patients who screened negative for BPD. No difference in the increase in PHQ-9 scores between these 2 groups was noted 1 month after treatment (P = 0.19). CONCLUSIONS: These data showed that a positive BPD screen does not necessarily predict a poorer response to ECT, nor does it predict greater symptom recurrence after ECT. This does not suggest that ECT is necessarily an appropriate treatment for major depressive disorder in patients with a comorbid BPD, given the limitations of screening instruments.

Effect of In-Class vs Online Education on Sexual Health Communication Skills in First-Year Medical Students: a Pilot Study.

OBJECTIVE: Online education is effective for knowledge acquisition, but its effect on clinical skill development is not well characterized. We aimed to compare communication skills of 50 first-year medical students who learned to assess and treat patients through an online learning module vs an in-class lecture. METHODS: Twenty-six students were randomized to learn about antidepressant-induced sexual dysfunction in class and 24 learned the same content through an online module. Students were individually observed conducting an interview with a standardized patient with antidepressant-induced sexual dysfunction. Students were assessed by faculty raters blinded to the student's learning mode. Standardized patients were asked about their willingness to have the student as their physician. RESULTS: More students who learned in class vs online demonstrated appropriate verbal empathy (18 [69%] vs 8 [33%]; P = 0.01), defined as completing each task in the "verbal empathy" assessment domain, as measured by a faculty rater. Other assessed variables were not significantly different. Standardized patients' willingness (vs unwillingness; P = 0.01) to have the student as their physician was associated with the demonstration (by faculty appraisal) of a number of basic skills: using open-ended questions, asking one question at a time, using gender-neutral terminology when asking about the patient's relationship, and using appropriate sexual-health terminology. CONCLUSIONS: This study, although limited by a single-site design and the small number of participants, offers preliminary evidence that, if confirmed, may suggest that in-class learning from a psychiatrist (vs from an online module) is associated with greater verbal empathy in the assessment of SSRI-related sexual dysfunction.

The outcome of patients with cultured pathogens at time of nonunion surgery.

The purpose of this study is to evaluate incidence, preoperative laboratory markers, and outcomes of patients who positively cultured pathogens (PCP) at time of surgery for long bone fracture nonunion. Two-hundred and eighty-eight patients were enrolled in a trauma study on long bone nonunion. Two-hundred and sixteen of those 288 patients were cultured at the time of fracture nonunion surgery. Laboratory data were collected prior to intervention and infectious laboratory markers ordered on patients suspected for infection. Patients were followed for one year. Wound complications, antibiotic use, healing, function, and re-admission for further surgery were assessed. Cultures returned positive on 59 patients (representing 20.5% of the 288 patient cohort or 27.3% of the 216 patients cultured in the operative suite). More PCP's (47.5%; 28 of 59) developed wound complications, with greater mean antibiotic duration and more frequent returns to the OR averaging 1.3 procedures per patient. Twelve-month follow-up was obtained on 249 of the 288 (86.5%) and PCPs reported globally worse function. Patients who PCP at the time of operative management for long bone nonunion was a prognostic indicator of poorer long-term functional outcomes.