A Wearable Upper Extremity Rehabilitation Device for Inducing Arm Swing in Gait Training.

This paper presents the design and validation of a proof-of-concept prototype for a wearable rehabilitation device to incorporate arm swing during gait rehabilitation. Unlike current stationary exoskeletons used for rehabilitation of upper limbs' function, assisting arm swing during gait requires inducing faster arm flexion/extension movements while maintaining the users' arms unconstrained in other directions. We developed a portable and underactuated system with features such as a large workspace and backdrivability to induce arm swing. Its wide workspace allowed the wearers to easily move their arms in different directions without any constraints. A modified double parallelogram linkage (mDPL) is proposed to allow the device to mimic the natural workspace of an arm. Additionally, a pulley drive and weight compensation system were created to place the motor on the users' back reducing the hindering weight of the actuators on their arms. Our experiments demonstrated this arm-swing rehabilitator could successfully induce arm movements at different arm configurations with low (0.67 Hz) and high (1.1 Hz) frequencies corresponding to slow and fast walking.

Socioeconomic disparities in treatment and survival in patients with hypopharyngeal malignancy.

BACKGROUND: This retrospective study utilizes The Surveillance, Epidemiology, and End Results database to investigate socioeconomic factors leading to treatment disparities in hypopharyngeal malignancy. METHODS: Treatment was compared to National Cancer Care Network guidelines. Novel analyses, including logistic modeling, allowed survival analysis and identification of socioeconomic variables not previously considered in staging and management guidelines. RESULTS: Black and older patients, and residence in low-income areas predict lower likelihood of standard therapy (p < 0.05). Early-stage disease and standard therapy correlate with improved survival (p < 0.001). Medicaid, advanced age, advanced disease, and treatment outside of consensus guidelines correlated with lower survival (p < 0.0001). CONCLUSIONS: There are clear socioeconomic factors impacting treatment and survival in hypopharyngeal malignancies. Standard therapy affords superior survival rate. Black, low socioeconomic status, and older patients are less likely to receive standard therapy. Education and language isolation do not predict treatment or survival. Understanding these discrepancies is paramount to palliating disparities in healthcare.

Deciphering Knowledge and Opinions of Human Papillomavirus and Human Papillomavirus Vaccination for Facilitation of Point-of-Care Vaccination in Adults.

Importance: Human papillomavirus (HPV) vaccination rates remain significantly below rates for other common childhood vaccines, which has implications for future rates of HPV-associated oropharyngeal squamous cell carcinoma (OPSCC). Objective: To assess whether individuals who were aware of the association between HPV and OPSCC would be more likely to have been previously vaccinated. Design, Setting, and Participants: This survey study included patients aged 18 to 45 years who sought routine outpatient care at the otolaryngology clinic at Boston Medical Center from September 1, 2020, to May 19, 2021. A survey (HPV-Associated Head and Neck Cancer Epidemiology, Awareness and Demographics) [HEAD]) composed of validated questions to assess patient knowledge of HPV and HPV vaccination and barriers to vaccination was delivered to participants. The survey was paired with a novel point-of-care vaccination program housed within an otolaryngology department. Main Outcomes and Measures: The main outcome was prevalence of knowledge of the relationship between HPV infection and OPSCC based on survey responses. The association of knowledge of HPV-associated OPSCC with likelihood of having been vaccinated was assessed in the overall cohort and by demographic characteristics using multivariate logistic regression. Results: Of 405 patients given the survey, 288 (71.1%) responded. Of these patients, 271 (94.1%) had surveys included; 158 (58.3%) were female, and median age was 29 years (IQR, 24-35 years). The baseline vaccination rate in the surveyed population was low (26.6%; n = 72) overall (10.6% among men [12 of 113]; 37.9% among women [60 of 158]). Few participants understood the relationship between HPV infection and OPSCC (63 of 271 [23.3%]) or that HPV-associated OPSCC is the most common HPV-associated cancer type (9 of 121 [7.4%]). Compared with men, women were more likely to have been previously vaccinated (odds ratio [OR], 6.5; 95% CI, 3.0-13.9), more aware that HPV causes cancer (OR, 3.7; 95% CI, 1.9-7.1), and more likely to have heard about HPV and HPV vaccination from their health care practitioner (OR, 2.6; 95% CI, 1.2-5.7). Knowledge of the relationship between HPV infection and cancer and between HPV and OPSCC was associated with increased likelihood of having been vaccinated (HPV and cancer: OR, 4.1 [95% CI, 1.8-9.5]; HPV and OPSCC: OR, 3.7 [95% CI, 1.8-7.6]). Among 156 unvaccinated participants, 12 of 98 men (12.2%) and 7 of 131 women (5.3%) received point-of-care vaccination. Conclusions: Most participants in this survey study were unaware that HPV causes OPSCC. Understanding that HPV causes OPSCC was associated with increased likelihood of having been vaccinated. However, most patients surveyed were not informed of this relationship by their health care practitioners. Targeted education aimed at unvaccinated adults establishing the relationship between HPV infection and OPSCC, paired with point-of-care vaccination, may be an innovative strategy for increasing HPV vaccination rates in adults.

Geographic Diversity Among Otolaryngology Residency Programs.

OBJECTIVE: To analyze geographic trends in the otolaryngology residency match. DESIGN: Cross-sectional study of 116 otolaryngology residency programs, including 1657 residents. SETTING: Internet. PARTICIPANTS: Medical school, undergraduate institution, and hometown of otolaryngology residents in the academic year 2019 to 2020 were recorded from programs' websites. Six military programs and 1 program in Puerto Rico were excluded. RESULTS: Of 1402 residents, 784 (55.9%) and 556 (39.6%) matched in the same region as their medical school for general and specific divisions, respectively. Residency programs in the South, Northeast, and Midwest had significantly more residents who went to medical school in the same division (p-value <0.02). 17.9% (252 of 1402) of residents matched at their same medical institution or an affiliated program, while 34.8% (208 of 597) and 44.8% (268 of 597) of residents matched at a division with no previous affiliation for general and specific divisions, respectively. CONCLUSIONS: Programs in the South, Midwest, and Northeast are more likely to have residents who graduated from medical schools in these respective divisions, while programs in the West are more likely to have residents who graduated from medical schools outside this division. Over a third of residents matched at programs in divisions with no previous affiliation. This information may be useful for applicants in deciding on application strategies and for programs seeking to improve their diversity.

The effects of forearm movements on human gait during walking with various self-selected speeds.

The forearms significantly contribute to the upper extremity movements and, consequently, whole-body responses during locomotion. The purpose of this study is to provide a more in-depth understanding of the mechanism controlling forearm movements during walking by comprehensively investigating the effects of the forearms on the lower and upper limb movements. Such an understanding can provide critical information for the design and control of robotic upper-limb prostheses. Twelve healthy young participants were recruited to compare their gait during (1) natural walking, (2) walking while wearing a pair of artificial passive forearms and having their actual forearms restrained by orthopedic braces, and (3) walking with only having their forearms restrained by the braces (i.e., no artificial forearms). While the passive forearms in condition 2 were to determine if the forearm movements were passively or actively controlled, condition 3 was to account for the effects of restraining the forearms in condition 2. The participants' lower-limb joint angles and spatiotemporal parameters remained unchanged across the three conditions while walking at their normal and fast self-selected gait speeds. However, significant decreases were observed in the shoulder and trunk angles, the interlimb coordination, and the shoulder-trunk correlations when walking with the artificial forearms. These observations were in tandem with the increased muscle activity of the biceps, trapeziuses, and posterior deltoids, which controlled the shoulder motion and trunk rotation during walking with the artificial forearms across both normal and fast self-selected speeds. Although not significant, the metabolic energy analysis of five participants revealed an increase during walking with artificial forearms. The results support the idea that the body actively controls the forearm movements through the shoulder and trunk rotations to mitigate the undesired disturbances induced by the passive forearm movements during locomotion.

Effects of COVID-19 on telemedicine practice patterns in outpatient otolaryngology.

OBJECTIVE: Otolaryngology is considered high risk for Coronavirus Disease 2019 (COVID-19) exposure and spread. This has led to a transition to telemedicine and directly impacts patient volume, evaluation and management practices. The objective of this study is to determine the impact of COVID-19 on patient characteristics in relation to outpatient attendance, ancillary testing, medical therapy, and surgical decision making. METHODS: A retrospective case series at an academic medical center was performed. Outpatient appointments from October 2019 (pre-COVID) and March 16-April 10, 2020 (COVID) were analyzed. Prevalence rates and odds ratios were used to compare demographics, visit characteristics, ancillary tests, medication prescribing, and surgical decisions between telemedicine and in-person visits, before and during COVID. RESULTS: There was a decrease in scheduled visits during the COVID timeframe, for both in-person and telemedicine visits, with a comparable proportion of no-shows. There was a higher overall percentage of Hispanic/Latino patients who received care during the COVID timeframe (OR = 1.43; 95% CI = 1.07-1.90) in both groups, although primary language was not significantly associated with attendance. There were fewer ancillary tests ordered (OR = 0.54) and more medications prescribed (OR = 1.59) during COVID telemedicine visits compared with pre-COVID in-person visits. CONCLUSION: COVID-19 has rapidly changed the use of telemedicine. Telemedicine can be used as a tool to reach patients with severe disease burden. Continued healthcare reform, expanded access to affordable care, and efficient use of resources is essential both during the current COVID-19 pandemic and beyond. LEVEL OF EVIDENCE: IV.

A novel excitatory network for the control of breathing.

Breathing must be tightly coordinated with other behaviours such as vocalization, swallowing, and coughing. These behaviours occur after inspiration, during a respiratory phase termed postinspiration. Failure to coordinate postinspiration with inspiration can result in aspiration pneumonia, the leading cause of death in Alzheimer's disease, Parkinson's disease, dementia, and other neurodegenerative diseases. Here we describe an excitatory network that generates the neuronal correlate of postinspiratory activity in mice. Glutamatergic-cholinergic neurons form the basis of this network, and GABA (γ-aminobutyric acid)-mediated inhibition establishes the timing and coordination relative to inspiration. We refer to this network as the postinspiratory complex (PiCo). The PiCo has autonomous rhythm-generating properties and is necessary and sufficient for postinspiratory activity in vivo.The PiCo also shows distinct responses to neuromodulators when compared to other excitatory brainstem networks. On the basis of the discovery of the PiCo, we propose that each of the three phases of breathing is generated by a distinct excitatory network: the pre-Bötzinger complex, which has been linked to inspiration; the PiCo, as described here for the neuronal control of postinspiration; and the lateral parafacial region (pF(L)), which has been associated with active expiration, a respiratory phase that is recruited during high metabolic demand.

Quantifying the π-Stacking Interactions in Nitroarene Binding Sites of Proteins.

Stacking interactions in nitroarene binding sites of proteins were studied through analyses of structures in the protein data bank (PDB), as well as DFT and ab initio computations applied to model systems. Stacked dimers of mono-, di-, and trinitrobenzene with the amino acid side chains histidine (His), phenylalanine (Phe), tyrosine (Tyr), and tryptophan (Trp) were optimized at the B97-D/TZV(2d,2p) level of theory. Binding energies for the global minimum dimer geometries were further refined at the estimated CCSD(T)/aug-cc-pVTZ level of theory. The results show that the interactions between aromatic amino acids and nitroarenes are very strong (up to -14.6 kcal mol(-1)), and the regiochemistry of the nitro substituents plays a significant role in the relative monomer orientations and strength of the interaction. In contrast to model stacked benzene dimers, effects of nitro substituents in stacking complexes with aromatic amino acid side chains are not perfectly additive. This is attributed to direct interactions of the nitro substituents with functional groups in the amino acid side chain. Overall, the strength of stacking interactions with these nitrobenzenes follows the order Trp > Tyr > Phe ≈ His. We also analyzed nitroarene binding sites in the PDB. Out of 216 selected crystal structures containing nitroarene ligands, 191 have nearby aromatic residues, providing 65 examples of π-stacking interactions involving a nitroarene. Of these, the representations of the different aromatic amino acids (Trp > Tyr > Phe > His) are correlated with the strength of model complexes of nitroarenes, with the exception of His. B97-D computations applied to complexes extracted from these crystal structures reveal that π-stacking interactions between the nitroarene and aromatic amino acid side chains exhibit a broad range of strengths, with many contributing significantly to binding.

Salvage palmar fasciectomy after initial treatment with collagenase clostridium histolyticum.

BACKGROUND: Collagenase clostridium histolyticum was approved for clinical use in 2010 and has become an accepted treatment modality for Dupuytren's contracture. Because longitudinal experience with injectable collagenase remains limited, the effect of treatment on future surgery is not well defined. METHODS: A retrospective review of the senior author's practice from February of 2010 through March of 2014 was performed. Eleven patients were identified who had digital or palmar fasciectomy after at least one previous injection of collagenase clostridium histolyticum. Cases were reviewed for functional outcomes and operative difficulty. RESULTS: Seven metacarpophalangeal joints and 12 proximal interphalangeal joints in 11 patients were treated. Nine of the 11 patients were referred to the senior author after collagenase clostridium histolyticum injections by other hand surgeons; two patients had previous injections by the senior author. The average interval between most recent injection and salvage fasciectomy was 12 months. Intraoperative findings demonstrated disruption of normal architecture and areolar tissue, with extensive scar in the dissection planes after previous injection. Mean preoperative/postinjection joint contracture for metacarpophalangeal and proximal interphalangeal joints was 42 and 60 degrees, respectively; after surgery, joint contractures were 0 and 21 degrees, respectively. Significant improvement in postoperative range of motion was seen for both metacarpophalangeal and proximal interphalangeal joints after palmar fasciectomy. CONCLUSIONS: Collagenase clostridium histolyticum injections may produce a deeply scarred bed and increase the technical difficulty of salvage fasciectomy. However, results of palmar fasciectomy are comparable to those of primary fasciectomy even in the setting of recurrent or progressive disease. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Anion-π interactions and positive electrostatic potentials of N-heterocycles arise from the positions of the nuclei, not changes in the π-electron distribution.

We show that the positive electrostatic potentials and molecular quadrupole moments characteristic of π-acidic azines, which underlie the ability of these rings to bind anions above their centres, arise from the position of nuclear charges, not changes in the π-electron density distribution.

Toward a more complete understanding of noncovalent interactions involving aromatic rings.

Noncovalent interactions involving aromatic rings, which include π-stacking interactions, anion-π interactions, and XH-π interactions, among others, are ubiquitous in chemical and biochemical systems. Despite dramatic advances in our understanding of these interactions over the past decade, many aspects of these noncovalent interactions have only recently been uncovered, with many questions remaining. We summarize our computational studies aimed at understanding the impact of substituents and heteroatoms on these noncovalent interactions. In particular, we discuss our local, direct interaction model of substituent effects in π-stacking interactions. In this model, substituent effects are dominated by electrostatic interactions of the local dipoles associated with the substituents and the electric field of the other ring. The implications of the local nature of substituent effects on π-stacking interactions in larger systems are discussed, with examples given for complexes with carbon nanotubes and a small graphene model, as well as model stacked discotic systems. We also discuss related issues involving the interpretation of electrostatic potential (ESP) maps. Although ESP maps are widely used in discussions of noncovalent interactions, they are often misinterpreted. Next, we provide an alternative explanation for the origin of anion-π interactions involving substituted benzenes and N-heterocycles, and show that these interactions are well-described by simple models based solely on charge-dipole interactions. Finally, we summarize our recent work on the physical nature of substituent effects in XH-π interactions. Together, these results paint a more complete picture of noncovalent interactions involving aromatic rings and provide a firm conceptual foundation for the rational exploitation of these interactions in a myriad of chemical contexts.

Evidence-based medicine: Metacarpal fractures.

LEARNING OBJECTIVES: After studying this article, the participant should be able to: (1) Determine the need for operative treatment of metacarpal fractures. (2) Describe the position of immobilization for nonoperative treatment of fifth metacarpal fractures. (3) Assess the differences between intramedullary pinning and transverse pinning of displaced metacarpal fractures. (4) Compare the advantages of plating and pinning for treatment of displaced metacarpal fractures. (5) Recognize appropriate timing and treatment of open metacarpal fractures. SUMMARY: The body of evidence regarding the treatment of metacarpal fractures continues to grow. Conservative management, closed reduction with percutaneous Kirschner wire fixation, intramedullary fixation, and open reduction and internal fixation with plates and/or screws are all accepted treatment modalities. The goal of this review is to highlight the most recent literature and the best evidence available for the management of metacarpal fractures.

Benchmark Torsional Potentials of Building Blocks for Conjugated Materials: Bifuran, Bithiophene, and Biselenophene.

The utility of π-conjugated oligomers and polymers continues to grow, and oligofurans, oligothiophenes, and oligoselenophenes have shown great promise in the context of organic electronic materials. Vital to the performance of these materials is the maintenance of planarity along the conjugated backbone. Consequently, there has been a great deal of work modeling the torsional behavior of these prototypical components of conjugated organic materials both in the gas and condensed phases. Such simulations generally rely on classical molecular mechanics force fields or density functional theory (DFT) potentials. Unfortunately, there is a lack of benchmark quality, converged ab initio torsional potentials for bifuran, bithiophene, and biselenophene against which these lower level theoretical methods can be calibrated. To remedy this absence, we present highly accurate torsional potentials for these three molecules based on focal point analyses. These potentials will enable the benchmarking and parametrization of DFT functionals and classical molecular mechanics force fields. Here, we provide an initial assessment of the performance of common DFT functional and basis set combinations, to identify methods that provide robust descriptions of the torsional behavior of these prototypical building blocks for conjugated systems.

CLOVES syndrome.

A cohort of patients with overgrowth syndromes has been identified with congenital lipomatous overgrowth, dysregulated fat deposits, and mixed vascular malformations. The acronym CLOVES was given on a heuristic basis to stand for congenital lipomatous overgrowth (CLO), vascular malformation (V), epidermal nevi (E), and scoliosis and spinal deformities (S). These patients have upper limb anomalies with variable phenotypes. Although hand anomalies alone cannot make the diagnosis, the foot, truncal, cutaneous and spinal anomalies are particularly diagnostic. CLOVES syndrome has emerged as a distinct clinical entity diagnosed by clinical and radiographic examinations. The overgrowth pattern is now easily distinguished from other overgrowth syndromes.

Current trends in the management of proximal interphalangeal joint injuries of the hand.

Injuries to the proximal interphalangeal joint are commonly encountered by the hand surgeon. Proper diagnosis and treatment are vital for optimal outcomes. Proper treatment of these injuries requires a working knowledge of the anatomy of the joint and an appreciation for principles for reduction, stabilization, and early rehabilitation to provide the best outcomes possible. Injuries can include fractures of the head of the proximal phalanx, dislocations, fracture dislocations, and fractures of the base of the middle phalanx. Similar to other aspects of plastic surgery, there is little high-level evidence guiding treatment and thus most treatment is based on level III or IV evidence. The goal for treatment of any injury around the proximal interphalangeal joint is to establish a congruent joint and allow for early motion. Stiffness and posttraumatic arthritis are common following these injuries. Salvage procedures are limited to arthrodesis and arthroplasty, neither of which can restore the normal function of the hand.

Current concepts in the evaluation and treatment of mallet finger injury.

The mallet finger is a frequently encountered fingertip injury that leads to extensor lag of the distal phalanx. Classification systems stratify these injuries as ranging from soft-tissue disruption of the extensor mechanism alone to those that have articular involvement and volar subluxation. The management of mallet finger injuries varies based on injury pattern and surgeon preference. These treatment options include splinting regimens, closed reduction and percutaneous pinning, and open reduction and internal fixation. Although the final goal of treatment is to establish a congruent joint, the efficacy of each treatment modality has been shown to vary.

Accelerating Ni(II) precatalyst initiation using reactive ligands and its impact on chain-growth polymerizations.

Nickel(II) complexes with varying reactive ligands, which were designed to selectively accelerate the initiation rate without influencing the propagation rate in the chain-growth polymerization of π-conjugated monomers, were investigated. Precatalysts with electronically varied reacting groups led to faster initiation rates and narrower molecular weight distributions. Computational studies revealed that the reductive elimination rates are largely modulated by the ability of the two reacting arenes to stabilize the increasing electron density on the catalyst during reductive elimination. Overall, these studies provide insight into a key mechanistic step of cross-coupling reactions (reductive elimination) and highlight the importance of initiation in controlled chain-growth polymerizations.

Broad Transferability of Substituent Effects in π-Stacking Interactions Provides New Insights into Their Origin.

Substituent effects in model stacked homodimers and heterodimers of benzene, borazine, and 1,3,5-triazine have been examined computationally. We show that substituent effects in these dimers are strongly dependent on the identity of the unsubstituted ring, yet are independent of the ring bearing the substituent. This supports the local, direct interaction model [J. Am. Chem. Soc. 2011, 133, 10262], which maintains that substituent effects in π-stacking interactions are dominated by through-space interactions of the substituents with the proximal vertex of the unsubstituted ring. In addition to dimers in which the unsubstituted ring is held constant, substituent effects are correlated in many other stacked dimers, including those in which neither the substituted nor unsubstituted rings are conserved. Whether substituent effects in a pair of dimers will be correlated is shown to hinge on the electrostatic components of the interaction energies, and the correlations are explained in terms of the interaction of the local dipole moments associated with the substituents and the electric fields of the unsubstituted rings. Overall, substituent effects are similar in two stacked dimers as long as the electric fields above the unsubstituted rings are similar, providing a more sound physical justification for the local, direct interaction model.

Aesthetic and functional satisfaction after monsplasty in the massive weight loss population.

BACKGROUND: The mons region is often affected by massive weight loss (MWL), with descent of the pubic area and residual adiposity. Thinning and resuspension are often performed concomitantly with abdominal contouring procedures. OBJECTIVES: Assess patient satisfaction, as well as functional and aesthetic results, after monsplasty in the MWL population. METHODS: The authors identified 54 consecutive female MWL patients (≥50 lbs) who had undergone abdominal contouring and completed at least 3 months of follow-up as potential subjects. Subjects were asked to complete a Mons Satisfaction Survey, either by phone or in person. Demographic and procedural data were collected from our prospective registry. Descriptive statistics were calculated with significance set at P value <.05. RESULTS: Thirty-one patients (57.8%) completed the survey. Average patient age was 46 ± 11.3 years. Mean maximum body mass index (BMI) was 52.0 ± 8.81 kg/m(2), mean current BMI was 31.0 ± 6.22 kg/m(2), and mean delta BMI was 20.7 ± 6.00 kg/m(2). Average pannus resection weight was 3.25 ± 2.03 kg. Visualization of the genitalia improved from 25.8% to 100% (P < .01). Patients rated the appearance of their mons as 3.18 ± 2.11 prior to surgery and 8.58 ± 1.73 after surgery (P < .001) on a scale of 1 to 10. Hygiene improved in 61.3% of patients, and sex life improved in 51.6%, with 32.3% of patients reporting increased genital sensitivity. Incontinence decreased from 22.6% to 12.9%, and 6 patients reported a change in urinary stream. CONCLUSIONS: Monsplasty at the time of abdominal contouring yields significant improvement in patient satisfaction levels and functional scores. With proper incisional design, monsplasty can be performed safely during abdominal contouring with high patient satisfaction to improve both form and function of the pubic region.