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1.
Sports Health ; : 19417381241231631, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38532528

ABSTRACT

CONTEXT: While current literature has explored the outcomes of athletes who return to sport (RTS) after anterior cruciate ligament (ACL) injuries, less is known about the outcomes of those who are unsuccessful in returning to sport. OBJECTIVE: To determine the rate of athletes who did not RTS after primary ACL reconstruction (ACLR) and to identify the specific subjective reasons for failure to RTS. DATA SOURCES: A comprehensive search of the PubMed/MEDLINE, Scopus, and Web of Science databases was conducted through April 2021. STUDY SELECTION: Eligible studies included those explicitly reporting the rate of failure for RTS after ACLR as well as providing details on reasons for athletes' inability to return; 31 studies met the inclusion criteria. STUDY DESIGN: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Level 2 to 4. DATA EXTRACTION: The reasons for failure to RTS referred to in our study are derived from those established previously in the studies included. Data were collected on the number of athletes, mean age, mean follow-up time, type of sport played, failure to RTS rate, and specific reasons for failure to return. RESULTS: The weighted rate of failure to RTS after ACLR was 25.5% (95% CI, 19.88-31.66). The estimated proportion of psychosocial-related reasons cited for failure to RTS was significantly greater than knee-related reasons for failure RTS (55.4% vs 44.6%, P < 0.01). The most cited reason for failure to RTS was fear of reinjury (33.0%). CONCLUSION: This study estimates the rate of failure to RTS after ACLR to be 25.5%, with the majority of athletes citing fear of reinjury as the major deterrent for returning to sports. We highlight how factors independent of surgical outcomes may impact an athlete's ability to return to play given that the predominant reason for no RTS after ACLR was unrelated to the knee.

2.
World Neurosurg ; 184: 322-330.e1, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38342177

ABSTRACT

BACKGROUND: In recent years, the use of intraoperative computer tomography-guided (CT-guided) navigation has gained significant popularity among health care providers who perform minimally invasive spine surgery. This review aims to identify and analyze trends in the literature related to the widespread adoption of CT-guided navigation in spine surgery, emphasizing the shift from conventional fluoroscopy-based techniques to CT-guided navigation. METHODS: Articles pertaining to this study were identified via a database review and were hierarchically organized based on the number of citations. An "advanced document search" was performed on September 28th, 2022, utilizing Boolean search operator terms. The 25 most referenced articles were combined into a primary list after sorting results in descending order based on the total number of citations. RESULTS: The "Top 25" list for intraoperative CT-guided navigation in spine surgery cumulatively received a total of 2742 citations, with an average of 12 new citations annually. The number of citations ranged from 246 for the most cited article to 60 for the 25th most cited article. The most cited article was a paper by Siewerdsen et al., with 246 total citations, averaging 15 new citations per year. CONCLUSIONS: Intraoperative CT-guided navigation is 1 of many technological advances that is used to increase surgical accuracy, and it has become an increasingly popular alternative to conventional fluoroscopy-based techniques. Given the increasing adoption of intraoperative CT-guided navigation in spine surgery, this review provides impactful evidence for its utility in spine surgery.


Subject(s)
Surgery, Computer-Assisted , Humans , Surgery, Computer-Assisted/methods , Spine/diagnostic imaging , Spine/surgery , Tomography, X-Ray Computed/methods , Minimally Invasive Surgical Procedures , Fluoroscopy/methods
3.
Stud Health Technol Inform ; 310: 1176-1180, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38270000

ABSTRACT

Given the importance of telemedicine in improving healthcare access for underserved patients, professional students need experience using virtual clinical workflows. We developed an educational workshop with (1) readings, (2) a knowledge assessment test, (3) dermatology and teledermatology lectures, (5) a telemedicine simulation with a standardized patient, and (6) a debriefing session. The simulation included a "hybrid" workflow with live videoconferencing and store-and-forward image review. We measured student performance using three American Association of Medical Colleges (AAMC) Telemedicine Competencies for medical education. Ninety-eight medical and physician assistant students completed this workshop between 2021 and 2022, and 80% were entrustable or approaching entrustment in each competency. Some students struggled with data collection and technology use. Our results suggest that this workshop offers a practical and generalizable way to teach about multiple virtual workflows and strengthen students' telemedicine competencies.


Subject(s)
Students , Telemedicine , Humans , Workflow , Educational Status , Computer Simulation
4.
Stud Health Technol Inform ; 310: 1201-1205, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38270005

ABSTRACT

While medication reconciliation is necessary to reduce errors, it is often challenging to gather an accurate history in the clinic. Telemedicine offers a relative advantage over clinic and hospital-based interviews by enabling the clinician to inspect the home environment, review pill bottles, and identify social determinants affecting adherence, such as financial instability. To be effective, however, clinicians must be trained in best-practice interview methods and the proper use of telemedicine. There is very little information in the literature describing the best strategies for teaching students or measuring competencies in telemedicine. Therefore, we created an educational module with a telemedicine simulation and an evaluation rubric. We piloted this module with 48 medical and physician assistant students. Most students could complete a virtual interview and gather a medication history. However, only half identified an over-the-counter medication missing from the list. Most students were either entrustable or approaching entrustment in the six telemedicine competencies measured in this simulation. This simulation is valuable for teaching students about medication reconciliation, using telemedicine to close gaps in access to care, and identifying health-related social needs affecting medication adherence.


Subject(s)
Medication Reconciliation , Telemedicine , Humans , Social Determinants of Health , Students , Educational Status
5.
J Arthroplasty ; 2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38220028

ABSTRACT

BACKGROUND: Postoperative infection is a devastating complication of total joint arthroplasty (TJA). Perioperative use of dexamethasone in patients who have diabetes mellitus (DM) remains controversial due to concern for increased infection risk. This study aimed to evaluate the association between dexamethasone and infection risk among patients who have DM undergoing TJA. METHODS: This was a retrospective cohort study conducted on adult patients who underwent primary, elective total knee arthroplasty (TKA) or total hip arthroplasty (THA) between January 2016 and December 2021 using a large national database. We identified 110,568 TJA patients (TKA: 66.6%; THA: 33.4%), 31.0% (34,298) of which had DM. Patients who received perioperative dexamethasone were compared to those who did not. The primary end points were the 90-day risk of postoperative periprosthetic joint infection, surgical site infection (SSI), and other non-SSI (urinary tract infection, pneumonia, sepsis). RESULTS: When modeling the association between dexamethasone exposure and study outcomes while accounting for the interaction between dexamethasone and morning blood glucose levels, dexamethasone administration conferred no increased odds of postoperative periprosthetic joint infection nor SSI in diabetics. However, dexamethasone significantly lowered the adjusted odds of other postoperative infections in diabetic patients (TKA: adjusted odds ratio = 09, 95% confidence interval = 0.8 to 1.0, P = .030; THA: adjusted odds ratio = 0.7, 95% confidence interval = 0.6 to 0.9, P = .001); specifically in patients with morning blood glucose levels between 110 to 248 mg/dL in TKA and ≤ 172 mg/dL in THA. CONCLUSIONS: This study provides strong evidence against withholding dexamethasone in diabetic patients undergoing TJA based on concern for infection. Instead, short-course perioperative dexamethasone reduced infection risk in select patients. The narrative surrounding dexamethasone should shift away from questions about whether dexamethasone is appropriate for diabetic patients, and instead focus on how best to optimize its use.

6.
J Arthroplasty ; 39(4): 1031-1035.e2, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37871859

ABSTRACT

BACKGROUND: Peripheral nerve injury (PNI) following revision total knee arthroplasty (rTKA) is a potentially devastating injury for patients. This study assessed the frequency of and risk factors for postoperative PNI following rTKA. METHODS: Patients who underwent rTKA from 2003 to 2015 were identified using the National Inpatient Sample. Demographics, medical histories, surgical details, and complications were compared between patients who sustained a PNI and those who did not to identify risk factors for the development of PNI after rTKA. RESULTS: Overall, 132,960 patients who underwent rTKA were identified, and 737 (0.56%) sustained a postoperative PNI. After adjusting for confounders, patients with a history of a spine condition (adjusted odds ratio [aOR]: 1.7, 95%-confidence interval 1.2 to 2.4, P = .003) and postoperative anemia (aOR: 1.3, 95%-CI: 1.1 to 1.5, P = .004) had higher risk of PNI following rTKA. Intraoperative periprosthetic fracture (aOR: 1.3, 0.78 to 2.2, P = .308), rheumatoid arthritis (aOR: 1.0, 95%-CI: 0.68 to 1.6, P = .865), and history of knee dislocation (aOR: 1.1, 95%-CI: 0.85 to 1.5, P = .412), were not significantly associated with higher risk for PNI. CONCLUSIONS: This study found a 0.56% incidence of PNI following rTKA, and patients who had preexisting spine conditions or postoperative anemia were at an increased risk for this complication. Orthopedic surgeons may use the results of this study to appropriately counsel patients on the potential for a PNI following rTKA.


Subject(s)
Anemia , Arthroplasty, Replacement, Knee , Peripheral Nerve Injuries , Humans , Arthroplasty, Replacement, Knee/adverse effects , Peripheral Nerve Injuries/epidemiology , Peripheral Nerve Injuries/etiology , Risk Factors , Incidence , Anemia/complications , Reoperation/adverse effects , Retrospective Studies
7.
J R Soc Interface ; 20(205): 20230177, 2023 08.
Article in English | MEDLINE | ID: mdl-37553992

ABSTRACT

With increasing evidence of electroreception in terrestrial arthropods, an understanding of receptor level processes is vital to appreciating the capabilities and limits of this sense. Here, we examine the spatio-temporal sensitivity of mechanoreceptive filiform hairs in detecting electrical fields. We first present empirical data, highlighting the time-varying characteristics of biological electrical signals. After which, we explore how electrically sensitive hairs may respond to such stimuli. The main findings are: (i) oscillatory signals (elicited by wingbeats) influence the spatial sensitivity of hairs, unveiling an inextricable spatio-temporal link; (ii) wingbeat direction modulates spatial sensitivity; (iii) electrical wingbeats can be approximated by sinusoidally modulated DC signals; and (iv) for a moving point charge, maximum sensitivity occurs at a faster timescale than a hair's frequency-based tuning. Our results show that electro-mechanical sensory hairs may capture different spatio-temporal information, depending on an object's movement and wingbeat and in comparison with aero-acoustic stimuli. Crucially, we suggest that electrostatic and aero-acoustic signals may provide distinguishable channels of information for arthropods. Given the pervasiveness of electric fields in nature, our results suggest further study to understand electrostatics in the ecology of arthropods and to reveal unknown ecological relationships and novel interactions between species.


Subject(s)
Arthropods , Animals , Movement , Electricity , Hair , Static Electricity
8.
Psychol Bull ; 149(1-2): 67-98, 2023.
Article in English | MEDLINE | ID: mdl-36913301

ABSTRACT

Past meta-analyses of the effects of priming on overt behavior have not examined whether the effects and processes of priming behavioral or nonbehavioral concepts (e.g., priming action through the word go and priming religion through the word church) differ, even though these possibilities are important to our understanding of concept accessibility and behavior. Hence, we meta-analyzed 351 studies (224 reports and 862 effect sizes) involving incidental presentation of behavioral or nonbehavioral primes, a neutral control group, and at least one behavioral outcome. Our random-effects analyses, which used the correlated and hierarchical effects model with robust variance estimation (Pustejovsky & Tipton, 2021; Tanner-Smith et al., 2016), revealed a moderate priming effect (d = 0.37) that remained stable across behavioral and nonbehavioral primes and across different methodological procedures and adjustments for possible inclusion/publication biases (e.g., sensitivity analyses from Mathur & VanderWeele, 2020; sensitivity analyses from Vevea & Woods, 2005). Although the findings suggest that associative processes explain both the effects of behavioral and nonbehavioral primes, lowering the value of a behavior weakened the effect only when the primes were behavioral. These findings support the possibility that even though both types of primes activate associations that promote behavior, behavioral (vs. nonbehavioral) primes may provide a greater opportunity for goals to control the effect of the primes. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

9.
J Theor Biol ; 558: 111357, 2023 02 07.
Article in English | MEDLINE | ID: mdl-36410450

ABSTRACT

The recent discovery that some terrestrial arthropods can detect, use, and learn from weak electrical fields adds a new dimension to our understanding of how organisms explore and interact with their environments. For bees and spiders, the filiform mechanosensory systems enable this novel sensory modality by carrying electric charge and deflecting in response to electrical fields. This mode of information acquisition opens avenues for previously unrealised sensory dynamics and capabilities. In this paper, we study one such potential: the possibility for an arthropod to locate electrically charged objects. We begin by illustrating how electrostatic interactions between hairs and surrounding electrical fields enable the process of location detection. After which we examine three scenarios: (1) the determination of the location and magnitude of multiple point charges through a single observation, (2) the learning of electrical and mechanical sensor properties and the characteristics of an electrical field through several observations, (3) the possibility that an observer can infer their location and orientation in a fixed and known electrical field (akin to "stellar navigation"). To conclude, we discuss the potential of electroreception to endow an animal with thus far unappreciated sensory capabilities, such as the mapping of electrical environments. Electroreception by terrestrial arthropods offers a renewed understanding of the sensory processes carried out by filiform hairs, adding to aero-acoustic sensing and opening up the possibility of new emergent collective dynamics and information acquisition by distributed hair sensors.


Subject(s)
Arthropods , Spiders , Bees , Animals , Arthropods/physiology , Spiders/physiology , Electricity , Hair/physiology
10.
AMIA Annu Symp Proc ; 2023: 474-483, 2023.
Article in English | MEDLINE | ID: mdl-38222442

ABSTRACT

In 2021, the Association of American Medical Colleges published Telehealth Competencies Across the Learning Continuum, a roadmap for designing telemedicine curricula and evaluating learners. While this document advances educators' shared understanding of telemedicine's core content and performance expectations, it does not include turn-key-ready evaluation instruments. At the University of Oklahoma School of Community Medicine, we developed a year-long telemedicine curriculum for third-year medical and second-year physician assistant students. We used the AAMC framework to create program objectives and instructional simulations. We designed and piloted an assessment rubric for eight AAMC competencies to accompany the simulations. In this monograph, we describe the rubric development, scores for students participating in simulations, and results comparing inter-rater reliability between faculty and standardized patient evaluators. Our preliminary work suggests that our rubric provides a practical method for evaluating learners by faculty during telemedicine simulations. We also identified opportunities for additional reliability and validity testing.


Subject(s)
Education, Medical, Undergraduate , Students, Medical , Telemedicine , Humans , Reproducibility of Results , Education, Medical, Undergraduate/methods , Telemedicine/methods , Students , Curriculum
11.
Obes Surg ; 32(12): 3973-3983, 2022 12.
Article in English | MEDLINE | ID: mdl-36198928

ABSTRACT

PURPOSE: Obesity is prevalent among economically disadvantaged and racially underrepresented populations. It has been suggested that socioeconomic factors, race, and lifestyle habits are important factors associated with weight loss and comorbidity remission after bariatric surgery. This study analyzes outcomes of bariatric surgery at a private hospital (PH) versus an affiliated safety-net hospital (SNH). METHODS: Retrospective review of laparoscopic sleeve gastrectomies (LSG) performed by the same surgeons at a PH and SNH in a large metropolitan setting. Demographics, socioeconomic status, insurance status, weight metrics, and perioperative outcomes were compared. A postoperative telephone survey was conducted to study dietary and lifestyle differences between cohorts. RESULTS: Of the 243 LSG performed, 141 (58%) occurred at PH versus 102 (42%) at SNH. Most patients at SNH were Hispanic, lower socioeconomic status, and had government-sponsored insurance. Based off the results from the postoperative telephone survey, there were no significant differences in dietary and lifestyle habits between both cohorts. Postoperative weight loss outcomes were similar across cohorts. The two groups had similar percent excess weight loss (EWL) at all time points up to 36 months and similar rates of failure to achieve 50% EWL at 12 months. However, patients at PH had greater resolution of diabetes and hypertension after surgery. CONCLUSION: Our study demonstrates outcomes after bariatric surgery are similar at a PH and its affiliated SNH. Despite differences in race and socioeconomic factors between the two cohorts, perioperative outcomes, short-term postoperative weight loss, and weight loss failure rates were equivalent between SNH and PH patients.


Subject(s)
Bariatric Surgery , Laparoscopy , Obesity, Morbid , Humans , Obesity, Morbid/surgery , Laparoscopy/methods , Gastrectomy/methods , Weight Loss , Bariatric Surgery/methods , Retrospective Studies , Social Class , Treatment Outcome
12.
Stud Health Technol Inform ; 294: 775-779, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35612202

ABSTRACT

Simulations offer a safe environment for health professional training and the opportunity to predictably and consistently introduce events or variables that may be rare or dangerous in a live setting. Exposing trainees to unanticipated events during simulations can improve their ability to adapt and improvise. The COVID-19 pandemic accelerated the adoption of telehealth worldwide and highlighted the need for better training in health professional schools. In the United States, the Association of American Medical Colleges (AAMC) published new telehealth competency standards in 2021. The AAMC stated that health care providers should be aware of the risks of technology failures, capable of troubleshooting them, and lead systems interventions to improve safety. However, the AAMC does not provide guidance on the specific failures or solutions. In this study, we developed a set of technology failures that can be simulated in a telehealth curriculum. We incorporated one technology failure into a simulated telehealth encounter and gathered students' (N = 53) feedback on the exercise. Students' feedback was overwhelmingly positive. They agreed that integrating technology failures into telehealth simulations provides important practice managing these events during clinical encounters. While telehealth is an important healthcare delivery modality that can improve access-to-care, it is imperative to train medical students to navigate technology failures so that can adeptly manage these issues in clinical practice.


Subject(s)
COVID-19 , Students, Medical , Telemedicine , COVID-19/epidemiology , Humans , Pandemics , Technology , United States
13.
Stud Health Technol Inform ; 294: 953-954, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35612255

ABSTRACT

We developed a teledermatology simulation to give medical and physician assistant students practice with live videoconferencing and store-and-forward workflows. The simulation included (1) pre-session reading; (2) a brief teledermatology didactic; (3) a simulated encounter with a standardized patient; and (4) faculty-led debriefs. The faculty observed students during the simulation and distributed a post-session learner satisfaction survey. Although students had mixed feelings about the simulation, 88% said the workshop met or exceeded expectations.


Subject(s)
Dermatology , Skin Diseases , Telemedicine , Delivery of Health Care , Humans , Students , Videoconferencing
14.
J R Soc Interface ; 19(188): 20220053, 2022 03.
Article in English | MEDLINE | ID: mdl-35317646

ABSTRACT

Recent investigations highlight the possibility of electroreception within arthropods through charged mechanosensory hairs. This discovery raises questions about the influence of electrostatic interaction between hairs and surrounding electrical fields within this sensory modality. Here, we investigate these questions by studying electrostatic coupling in arrays of hairs. We establish the notion of sensitivity contours that indicate regions within which point charges deflect hairs beyond a given threshold. We then examine how the contour's shape and size and the overall hair behaviour change in response to variations in the coupling between hairs. This investigation unveils synergistic behaviours whereby the sensitivity of hairs is enhanced or inhibited by neighbouring hairs. The hair spacing and ratio of a system's electrical parameters to its mechanical parameters influence this behaviour. Our results indicate that electrostatic interaction between hairs leads to emergent sensory properties for biologically relevant parameter values. The analysis raises new questions around the impact of electrostatic interaction on the current understanding of sensory hair processes, such as acoustic sensing, unveiling new sensory capabilities within electroreception such as amplification of hair sensitivity and location detection of charges in the environment.


Subject(s)
Arthropods , Animals , Electricity , Hair , Mechanoreceptors/physiology
15.
AMIA Annu Symp Proc ; 2022: 700-708, 2022.
Article in English | MEDLINE | ID: mdl-37128368

ABSTRACT

Educators must provide controlled scenarios for health professional students to develop patient safety competencies related to telemedicine, including when and how to escalate care. We developed a telepsychiatry workshop to give students experience with a high-stakes mental health condition. The workshop included (1) pre-session readings; (2) didactics on mood disorders and telepsychiatry; (3) a motivational interviewing exercise; (4) a simulated telemedicine encounter; and (5) a faculty-led group debrief. We evaluated teaching effectiveness using a competency assessment with three scales: (1) medical knowledge; (2) interpersonal and communication skills; and (3) telemedicine competencies. Between 0 and 59% of students were entrustable for each telemedicine competency. Our workshop demonstrates how to teach students about the safe use of telehealth technology and provides practice triaging mental health conditions commonly encountered in primary care and mental health telemedicine clinics.


Subject(s)
Psychiatry , Suicide , Telemedicine , Humans , Curriculum , Psychiatry/education , Education, Medical, Graduate , Clinical Competence
16.
Open Access J Sports Med ; 12: 129-138, 2021.
Article in English | MEDLINE | ID: mdl-34512045

ABSTRACT

Anterior cruciate ligament reconstructions (ACLR) are a relatively common procedure in orthopedic sports medicine with an estimated 130,000 arthroscopic operations performed annually. Most procedures are carried out on an outpatient basis, and though success rates of ACLR are as high as 95%, pain remains the most common postoperative complication delaying patient discharge, and thereby increasing the costs associated with patient care. Despite the success and relative frequency of ACLR surgery, optimal and widely accepted strategies and regimens for controlling perioperative pain are not well established. In recent years, the paradigm of pain control has shifted from exclusively utilizing opiates and opioid medications in the acute postoperative period to employing other agents and techniques including nerve blocks, intra-articular and periarticular injections of local anesthetic agents, NSAIDs, and less commonly, ketamine, tranexamic acid (TXA), sedatives, gabapentin, and corticosteroids. More often, these agents are now used in combination and in synergy with one another as part of a multimodal approach to pain management in ACLR, with the goal of reducing postoperative pain, opioid consumption, and the incidence of delayed hospital discharge. The purpose of this review is to consolidate current literature on various agents involved in the management of postoperative pain following ACLR, including the role of classically used opiate and opioid medications, as well as to describe other drugs currently utilized in practice either individually or in conjunction with other agents as part of a multimodal regimen in pain management in ACLR.

17.
Sci Rep ; 11(1): 18171, 2021 09 13.
Article in English | MEDLINE | ID: mdl-34518584

ABSTRACT

Understanding how fish associate with habitats across marine landscapes is crucial to developing effective marine spatial planning (MSP) in an expanding and diversifying ocean economy. Globally, anthropogenic pressures impact the barely understood temperate mesophotic ecosystems and South Africa's remote Amathole shelf is no exception. The Kei and East London region encompass three coastal marine protected areas (MPAs), two of which were recently extended to the shelf-edge. The strong Agulhas current (exceeding 3 m/s), which runs along the narrow shelf exacerbates sampling challenges. For the first time, a remotely operated vehicle (ROV) surveyed fish and their associated habitats across the shelf. Results indicated fish assemblages differed between the two principle sampling areas, and across the shelf. The number of distinct fish assemblages was higher inshore and on the shelf-edge, relative to the mid-shelf. However, the mid-shelf had the highest species richness. Unique visuals of rare Rhinobatos ocellatus (Speckled guitarfish) and shoaling Polyprion americanus (wreckfish) were collected. Visual evidence of rhodolith beds, deep-water lace corals and critically endangered endemic seabreams were ecologically important observations. The ROV enabled in situ sampling without damaging sensitive habitats or extracting fish. This study provided information that supported the Amathole MPA expansions, which extended protection from the coast to beyond the shelf-edge and will guide their management. The data gathered provides baseline information for future benthopelagic fish and habitat monitoring in these new MPAs.

18.
J Theor Biol ; 530: 110871, 2021 12 07.
Article in English | MEDLINE | ID: mdl-34411607

ABSTRACT

We study the mechanics of mechanoreceptor hairs in response to electro- and acousto-stimuli to expand the theory of tuning within filiform mechano-sensory systems and show the physical, biological and parametric feasibility of electroreception in comparison to aerodynamic sensing. We begin by analysing two well-known mechanosensory systems, the MeD1 spider trichobothria and the cricket cercal hair, offering a systematic appraisal of the physics of mechanosensory hair motion. Then we explore the biologically relevant parameter space of mechanoreceptor hairs by varying each oscillator parameter, thereby extending the theory to general arthropods. In doing so, we readily identify combinations of parameters for which a hair shows an enhanced or distinct response to either electric or aerodynamic stimuli. Overall, we find distinct behaviours in the two systems with novel insight provided through the parameter-space analysis. We show how the parameter space and balance of parameters therein of the resonant spider system are organised to produce a highly tuneable hair system through variation of hair length, whilst the broader parameter space of the non-resonant cricket system responds equally to a wider range of driving frequencies with increased capacity for high temporal resolution. From our analysis, we hypothesise the existence of two distinct types of mechanoreceptive system: the general system where hairs of all lengths are poised to detect both electro- and acousto- stimuli, and a stimuli-specific system where the sensitivity and specificity of the hairs to the different stimuli changes with length.


Subject(s)
Arthropods , Animals , Hair , Mechanoreceptors , Motion , Static Electricity
19.
Angew Chem Int Ed Engl ; 60(34): 18660-18665, 2021 08 16.
Article in English | MEDLINE | ID: mdl-33856106

ABSTRACT

A key aim of biocatalysis is to mimic the ability of eukaryotic cells to carry out multistep cascades in a controlled and selective way. As biocatalytic cascades get more complex, reactions become unattainable under typical batch conditions. Here a number of continuous flow systems were used to overcome batch incompatibility, thus allowing for successful biocatalytic cascades. As proof-of-principle, reactive carbonyl intermediates were generated in situ using alcohol oxidases, then passed directly to a series of packed-bed modules containing different aminating biocatalysts which accordingly produced a range of structurally distinct amines. The method was expanded to employ a batch incompatible sequential amination cascade via an oxidase/transaminase/imine reductase sequence, introducing different amine reagents at each step without cross-reactivity. The combined approaches allowed for the biocatalytic synthesis of the natural product 4O-methylnorbelladine.


Subject(s)
Alcohol Oxidoreductases/metabolism , Amines/metabolism , Biological Products/metabolism , Amines/chemistry , Biocatalysis , Biological Products/chemistry , Molecular Structure
20.
Nat Chem ; 13(2): 140-148, 2021 02.
Article in English | MEDLINE | ID: mdl-33380742

ABSTRACT

Finding faster and simpler ways to screen protein sequence space to enable the identification of new biocatalysts for asymmetric synthesis remains both a challenge and a rate-limiting step in enzyme discovery. Biocatalytic strategies for the synthesis of chiral amines are increasingly attractive and include enzymatic asymmetric reductive amination, which offers an efficient route to many of these high-value compounds. Here we report the discovery of over 300 new imine reductases and the production of a large (384 enzymes) and sequence-diverse panel of imine reductases available for screening. We also report the development of a facile high-throughput screen to interrogate their activity. Through this approach we identified imine reductase biocatalysts capable of accepting structurally demanding ketones and amines, which include the preparative synthesis of N-substituted ß-amino ester derivatives via a dynamic kinetic resolution process, with excellent yields and stereochemical purities.


Subject(s)
High-Throughput Screening Assays/methods , Oxidoreductases/isolation & purification , Amination/drug effects , Amines/chemistry , Biocatalysis , Imines/metabolism , Ketones/chemistry , Oxidoreductases/metabolism , Stereoisomerism
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