Selective Induction of Molecular Assembly to Tissue-Level Anisotropy on Peptide-Based Optoelectronic Cardiac Biointerfaces.

The conduction efficiency of ions in excitable tissues and of charged species in organic conjugated materials both benefit from having ordered domains and anisotropic pathways. In this study, a photocurrent-generating cardiac biointerface is presented, particularly for investigating the sensitivity of cardiomyocytes to geometrically comply to biomacromolecular cues differentially assembled on a conductive nanogrooved substrate. Through a polymeric surface-templated approach, photoconductive substrates with symmetric peptide-quaterthiophene (4T)-peptide units assembled as 1D nanostructures on nanoimprinted polyalkylthiophene (P3HT) surface are developed. The 4T-based peptides studied here can form 1D nanostructures on prepatterned polyalkylthiophene substrates, as directed by hydrogen bonding, aromatic interactions between 4T and P3HT, and physical confinement on the nanogrooves. It is observed that smaller 4T-peptide units that can achieve a higher degree of assembly order within the polymeric templates serve as a more efficient driver of cardiac cytoskeletal anisotropy than merely presenting aligned -RGD bioadhesive epitopes on a nanotopographic surface. These results unravel some insights on how cardiomyocytes perceive submicrometer dimensionality, local molecular order, and characteristics of surface cues in their immediate environment. Overall, the work offers a cardiac patterning platform that presents the possibility of a gene modification-free cardiac photostimulation approach while controlling the conduction directionality of the biotic and abiotic components.

Quality of life issues in patients with bone metastases: A systematic review.

INTRODUCTION: Bones are frequent sites of metastatic disease, observed in 30-75% of advanced cancer patients. Quality of life (QoL) is an important endpoint in studies evaluating the treatments of bone metastases (BM), and many patient-reported outcome tools are available. The primary objective of this systematic review was to compile a list of QoL issues relevant to BM and its interventions. The secondary objective was to identify common tools used to assess QoL in patients with BM, and the QoL issues they fail to address. METHODS: A search was conducted on Ovid MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases between 1946 and 27 January 2023 with the keywords "bone metastases", "quality of life", and "patient reported outcomes". Specific QoL issues in original research studies and the QoL tools used were extracted. RESULTS: The review identified the QoL issues most prevalent to BM in the literature. Physical and functional issues observed in patients included pain, interference with ambulation and daily activities, and fatigue. Psychological symptoms, such as helplessness, depression, and anxiety were also common. These issues interfered with patients' relationships and social activities. Items not mentioned in existing QoL tools were related to newer treatments of BM, such as pain flare, flu-like symptoms, and jaw pain due to osteonecrosis. CONCLUSIONS: This systematic review highlights that QoL issues for patients with BM have expanded over time due to advances in BM-directed treatments. If they are relevant, additional treatment-related QoL issues identified need to be validated prospectively by patients and added to current assessment tools.

Evaluation of Real and Perceived Risk to Health Care Workers Caring for Patients With the Omicron Variant of the SARS-CoV-2 Virus in Surgery and Obstetrics.

OBJECTIVES: The Omicron variant of the SARS-CoV-2 virus is described as more contagious than previous variants. We sought to assess risk to health care workers (HCWs) caring for patients with COVID-19 in surgical/obstetrical settings, and the perception of risk among this group. METHODS: From January to April 2022, reverse transcription polymerase chain reaction was used to detect the presence of SARS-CoV-2 viral ribonucleic acid in patient, environmental (floor, equipment, passive air) samples, and HCWs' masks (inside surface) during urgent surgery or obstetrical delivery for patients with SARS-CoV-2 infection. The primary outcome was the proportion of HCWs' masks testing positive. Results were compared with our previous cross-sectional study involving obstetrical/surgical patients with earlier variants (2020-2021). HCWs completed a risk perception electronic questionnaire. RESULTS: Eleven patients were included: 3 vaginal births and 8 surgeries. In total, 5/108 samples (5%) tested positive (SARS-CoV-2 Omicron) viral ribonucleic acid: 2/5 endotracheal tubes, 1/22 floor samples, 1/4 patient masks, and 1 nasal probe. No samples from the HCWs' masks (0/35), surgical equipment (0/10), and air (0/11) tested positive. No significant differences were found between the Omicron and 2020/21 patient groups' positivity rates (Mann-Whitney U test, P = 0.838) or the level of viral load from the nasopharyngeal swabs (P = 0.405). Nurses had a higher risk perception than physicians (P = 0.038). CONCLUSION: No significant difference in contamination rates was found between SARS-CoV-2 Omicron BA.1 and previous variants in surgical/obstetrical settings. This is reassuring as no HCW mask was positive and no HCW tested positive for COVID-19 post-exposure.

Risk Stratification in a Tertiary Care Spine Centre: Comparison Between STarTBack and OSPRO-YF Screening Tools.

Purpose: STarT Back Screening Tool and OSPRO-YF scales have been reported to be accurate tools for estimating risk for the development of persistent pain or prolonged disability in primary care settings. We performed a comparison of construct convergent and known-group validity and ceiling floor effect (CFE) of these tools using a common sample of patients seen at a tertiary care spine centre. Methods: This was a cross-sectional study of patients with and without a work-related back injury. The Hospital Anxiety and Depression Scale (HADS) was used as the reference outcome measure for convergent validity. For known-group validity, we examined the ability of the scales to differentiate between different levels of compensation, presence of non-organic signs, and work status. The CFE values were calculated. Results: Fifty consecutive injured workers were included along with 50 patients without an active compensation claim related to their low back pain. STarTBack and OSPRO-YF had moderate to high associations with the depression component of the HADS (0.69 to 0.77 respectively) with a statistically significant difference in favour of the OSPRO-YF. STarTBack's risk stratification categories were able to differentiate patients with a compensable injury, non-organic signs, and inability to work (p values ranging from 0.002 to < 0.001). The physical activity and work fear-avoidance beliefs constructs of the OSPRO-YF consistently outperformed other yellow flag constructs (p values ranging from 0.008 to < 0.001). The psychological sub-score of STarTBack showed a ceiling effect. There was a floor effect for the negative affect domain of OSPRO-YF. Neither total score had a floor or ceiling effect. Conclusions: STarTBack and OSPRO-YF are short screening tools with acceptable convergent and known-group construct validity and no floor or ceiling effect of their total score. Both tools could assist with the identification, evaluation, and management of psychological distress in patients presenting to tertiary care spine centres.

Objectif : l'outil de dépistage STarT Back et les échelles OSPRO-YF sont considérés comme des mécanismes précis pour estimer le risque d'apparition d'une douleur persistante ou d'une invalidité prolongée en soins primaires. Les chercheurs ont comparé la validité convergente de construit, la validité des groupes connus et l'effet plafond-plancher (EPP) de ces outils auprès d'un échantillon commun de patients suivis dans un centre tertiaire du rachis. Méthodologie : étude transversale de patients atteints ou non d'une blessure dorsale liée au travail. Les chercheurs ont utilisé l'échelle HADS (anxiété et dépression à l'hôpital) comme mesure de référence des résultats pour déterminer la validité convergente. Pour ce qui est de la validité des groupes connus, ils ont examiné la capacité des échelles à distinguer les divers taux d'indemnisation, la présence de signes non organiques et la situation d'emploi et ont calculé les valeurs de l'EPP. Résultats : cinquante (50) travailleurs blessés consécutifs ont participé à l'étude, de même que 50 patients n'ayant pas de réclamation d'indemnisation active liée à leur douleur lombaire. Les outils STarTBack et OSPRO-YF étaient dotés d'associations modérées à élevées avec l'élément « depression ¼ de l'échelle HADS (0,69 à 0,77. respectivement), et la différence en faveur de l'échelle OSPRO-YF était statistiquement significative. Les catégories de stratification du risque de l'outil STarTBack pouvaient distinguer les patients atteints d'une blessure justifiant une indemnisation, les signes non organiques et l'incapacité de travailler (valeurs p de 0,002 à < 0,001). Les construits de l'activité physique et des comportements d'appréhension ou d'évitement de l'échelle OSPRO-YF étaient constamment supérieurs aux autres construits de drapeau jaune (valeurs p de 0,008 à < 0,001). Le sous-score psychologique de l'outil STarTBack avait un effet plafond, tandis que le domaine d'affect négatif de l'échelle OSPRO-YF avait un effet plancher. Aucun des scores totaux n'avait d'effet plancher ou plafond. Conclusions : STarTBack et OSPRO-YF sont de courts outils de dépistage à la validité de construit convergente et de groupes connus et dont le score total n'a ni effet plancher ni effet plafond. Les deux outils pourraient contribuer à déterminer, à évaluer et à prendre en charge la détresse psychologique chez les parents qui consultent dans un centre tertiaire du rachis.

Machine learning models can predict subsequent publication of North American Spine Society (NASS) annual general meeting abstracts.

BACKGROUND CONTEXT: Academic meetings serve as an opportunity to present and discuss novel ideas. Previous studies have identified factors predictive of publication without generating predictive models. Machine learning (ML) presents a novel tool capable of generating these models. As such, the objective of this study was to use ML models to predict subsequent publication of abstracts presented at a major surgical conference. STUDY DESIGN/SETTING: Database study. METHODS: All abstracts from the North American Spine Society (NASS) annual general meetings (AGM) from 2013-2015 were reviewed. The following information was extracted: number of authors, institution, location, conference category, subject category, study type, data collection methodology, human subject research, and FDA approval. Abstracts were then searched on the PubMed, Google Scholar, and Scopus databases for publication. ML models were trained to predict whether the abstract would be published or not. Quality of models was determined by using the area under the receiver operator curve (AUC). The top ten most important factors were extracted from the most successful model during testing. RESULTS: A total of 1119 abstracts were presented, with 553 (49%) abstracts published. During training, the model with the highest AUC and accuracy metrics was the partial least squares (AUC of 0.77±0.05, accuracy of 75.5%±4.7%). During testing, the model with the highest AUC and accuracy was the random forest (AUC of 0.69, accuracy of 67%). The top ten features for the random forest model were (descending order): number of authors, year, conference category, subject category, human subjects research, continent, and data collection methodology. CONCLUSIONS: This was the first study attempting to use ML to predict the publication of complete articles after abstract presentation at a major academic conference. Future studies should incorporate deep learning frameworks, cognitive/results-based variables and aim to apply this methodology to larger conferences across other fields of medicine to improve the quality of works presented.

Comparison of major spine navigation platforms based on key performance metrics: a meta-analysis of 16,040 screws.

PURPOSE: The objective of this meta-analysis is to compare available computer-assisted navigation platforms by key performance metrics including pedicle screw placement accuracy, operative time, neurological complications, and blood loss. METHODS: A systematic review was conducted using major databases for articles comparing pedicle screw accuracy of computer-assisted navigation to conventional (freehand or fluoroscopy) controls via post-operative computed tomography. Outcome data were extracted and pooled by random-effects model for analysis. RESULTS: All navigation platforms demonstrated significant reduction in risk of breach, with Stryker demonstrating the highest accuracy compared to controls (OR 0.16 95% CI 0.06 to 0.41, P < 0.00001, I2 = 0%) followed by Medtronic. There were no significant differences in accuracy or most surgical outcome measures between platforms; however, BrainLab demonstrated significantly faster operative time compared to Medtronic by 30 min (95% CI - 63.27 to - 2.47, P = 0.03, I2 = 74%). Together, there was significantly lower risk of major breach in the navigation group compared to controls (OR 0.42, 95% CI 0.27-0.63, P < 0.0001, I2 = 56%). CONCLUSIONS: When comparing between platforms, Stryker demonstrated the highest accuracy, and Brainlab the shortest operative time, both followed by Medtronic. No significant difference was found between platforms regarding neurologic complications or blood loss. Overall, our results demonstrated a 60% reduction in risk of major breach utilizing computer-assisted navigation, coinciding with previous studies, and supporting its validity. This study is the first to directly compare available navigation platforms offering insight for further investigation and aiding in the institutional procurement of platforms. LEVEL 3 EVIDENCE: Meta-analysis of Level 3 studies.

Safety and Efficacy of Riluzole in Acute Spinal Cord Injury Study (RISCIS): A Multi-Center, Randomized, Placebo-Controlled, Double-Blinded Trial.

Riluzole is a sodium-glutamate antagonist that attenuates neurodegeneration in amyotrophic lateral sclerosis (ALS). It has shown favorable results in promoting recovery in pre-clinical models of traumatic spinal cord injury (tSCI) and in early phase clinical trials. This study aimed to evaluate the efficacy and safety of riluzole in acute cervical tSCI. An international, multi-center, prospective, randomized, double-blinded, placebo-controlled, adaptive, Phase III trial (NCT01597518) was undertaken. Patients with American Spinal Injury Association Impairment Scale (AIS) A-C, cervical (C4-C8) tSCI, and <12 h from injury were randomized to receive either riluzole, at an oral dose of 100 mg twice per day (BID) for the first 24 h followed by 50 mg BID for the following 13 days, or placebo. The primary efficacy end-point was change in Upper Extremity Motor (UEM) scores at 180 days. The primary efficacy analyses were conducted on an intention to treat (ITT) and completed cases (CC) basis. The study was powered at a planned enrolment of 351 patients. The trial began in October 2013 and was halted by the sponsor on May 2020 (and terminated in April 2021) in the face of the global COVID-19 pandemic. One hundred ninety-three patients (54.9% of the pre-planned enrolment) were randomized with a follow-up rate of 82.7% at 180 days. At 180 days, in the CC population the riluzole-treated patients compared with placebo had a mean gain of 1.76 UEM scores (95% confidence interval: -2.54-6.06) and 2.86 total motor scores (CI: -6.79-12.52). No drug-related serious adverse events were associated with the use of riluzole. Additional pre-planned sensitivity analyses revealed that in the AIS C population, riluzole was associated with significant improvement in total motor scores (estimate: standard error [SE] 8.0; CI 1.5-14.4) and upper extremity motor scores (SE 13.8; CI 3.1-24.5) at 6 months. AIS B patients had higher reported independence, measured by the Spinal Cord Independence Measure score (45.3 vs. 27.3; d: 18.0 CI: -1.7-38.0) and change in mental health scores, measured by the Short Form 36 mental health domain (2.01 vs. -11.58; d: 13.2 CI: 1.2-24.8) at 180 days. AIS A patients who received riluzole had a higher average gain in neurological levels at 6 months compared with placebo (mean 0.50 levels gained vs. 0.12 in placebo; d: 0.38, CI: -0.2-0.9). The primary analysis did not achieve the predetermined end-point of efficacy for riluzole, likely related to insufficient power. However, on pre-planned secondary analyses, all subgroups of cervical SCI subjects (AIS grades A, B and C) treated with riluzole showed significant gains in functional recovery. The results of this trial may warrant further investigation to extend these findings. Moreover, guideline development groups may wish to assess the possible clinical relevance of the secondary outcome analyses, in light of the fact that SCI is an uncommon orphan disorder without an accepted neuroprotective treatment.

Key Stakeholder Perceptions of Standard vs. Total Cost of Ownership: A Procurement Analysis for Orthopaedic-Powered Instruments.

This study compares standard procurement methodology (SPM) with total cost of ownership (TCO) methodology for the procurement of orthopaedic-powered instruments. The authors conducted semi-structured standardized interviews with key hospital procurement stakeholders following consolidated criteria for reporting qualitative research. Of the 33 hospital procurement stakeholders interviewed, all (100%) reported that SPM would be easier to use than TCO. However, only six (18%) preferred SPM over TCO. Barriers to the adoption of TCO emerged as a theme. Creating TCO frameworks can help to simplify the process for procurement agents and facilitate its adoption in the healthcare sector.

Development and validation of a radiofrequency ablation treatment planning system for vertebral metastases.

PURPOSE: Bone-targeted radiofrequency ablation (RFA) is widely used in the treatment of vertebral metastases. While radiation therapy utilizes established treatment planning systems (TPS) based on multimodal imaging to optimize treatment volumes, current RFA of vertebral metastases has been limited to qualitative image-based assessment of tumour location to direct probe selection and access. This study aimed to design, develop and evaluate a computational patient-specific RFA TPS for vertebral metastases. METHODS: A TPS was developed on the open-source 3D slicer platform, including procedural setup, dose calculation (based on finite element modelling), and analysis/visualization modules. Usability testing was carried out by 7 clinicians involved in the treatment of vertebral metastases on retrospective clinical imaging data using a simplified dose calculation engine. In vivo evaluation was performed in a preclinical porcine model (n = 6 vertebrae). RESULTS: Dose analysis was successfully performed, with generation and display of thermal dose volumes, thermal damage, dose volume histograms and isodose contours. Usability testing showed an overall positive response to the TPS as beneficial to safe and effective RFA. The in vivo porcine study showed good agreement between the manually segmented thermally damaged volumes vs. the damage volumes identified from the TPS (Dice Similarity Coefficient = 0.71 ± 0.03, Hausdorff distance = 1.2 ± 0.1 mm). CONCLUSION: A TPS specifically dedicated to RFA in the bony spine could help account for tissue heterogeneities in both thermal and electrical properties. A TPS would enable visualization of damage volumes in 2D and 3D, assisting clinicians in decisions about potential safety and effectiveness prior to performing RFA in the metastatic spine.

Literature review on the use of methoxyflurane in the management of pain in cancer-related procedures.

INTRODUCTION: Self-administered methoxyflurane, also known as Penthrox, at a sub-anesthetic dose is a short-term, fast-acting, and safe analgesic that may provide suitable pain relief for cancer patients. This review aims to compile the existing evidence on methoxyflurane and its efficacy in reducing pain during cancer-related procedures. METHODS: A literature search was conducted through OVID Medline and Embase. The search was limited to articles published between 2012 and 2021 and studies were included if they assessed the efficacy of methoxyflurane to reduce pain in cancer-related procedures. All types of cancer were included. RESULTS: The literature search yielded seven studies published between 2012 and 2021. The studies analyzed assessed methoxyflurane use in prostate biopsy, colonoscopy, removal of brachytherapy rods, and bone marrow biopsy. Various research designs were employed, including three randomized controlled trials, two prospective observational studies, one retrospective, and one non-randomized controlled trial. In all, methoxyflurane has a demonstrated ability to reduce pain in these procedures. CONCLUSION: In the limited studies available in evaluating the efficacy of methoxyflurane for reducing procedural pain during cancer-related procedures, all have demonstrated clinical equivalency or superiority. Pain relief appears to be equivalent however methoxyflurane overcomes the standard limitations of respiratory sedation and has demonstrated quicker procedural recovery times than traditional sedation methods. The accumulated data to date supports the use of methoxyflurane which can supplement or supplant current methods of analgesia in cancer-related procedures.

Patient-Reported Outcomes Following Surgery for Lumbar Disc Herniation: Comparison of a Universal and Multitier Health Care System.

STUDY DESIGN: Ambispective cohort study. OBJECTIVE: Canada has a government-funded universal health care system. The United States utilizes a multitier public and private system. The objective is to investigate differences in clinical outcomes between those surgically treated for lumbar disc herniation in a universal health care and multitier health system. METHODS: Surgical lumbar disc herniation patients enrolled in the Canadian Spine Outcome Research Network (CSORN) were compared with the surgical cohort enrolled in the Spine Patients Outcome Research Trial (SPORT) study. Baseline demographics and spine-related patient-reported outcomes (PROs) were compared at 3 months and 1 year post-operatively. RESULTS: The CSORN cohort consisted of 443 patients; the SPORT cohort had 763 patients. Patients in the CSORN cohort were older (46.4 ± 13.5 vs 41.0 ± 10.8, P < .001) and were more likely to be employed (69.5% vs 60.3%, P = .003). The CSORN cohort demonstrated significantly greater rates of satisfaction after surgery at 3 months (87.2% vs 64.8%, P < .0001) and 1 year (85.6% vs 69.6%, P < .0001). Improvements in back and leg pain followed similar trajectories in the two cohorts, but there was less improvement on ODI in the CSORN cohort (P < .01). On multivariable logistic regression, the CSORN cohort was a significant independent predictor of patient satisfaction at 1-year follow-up (P < .001). CONCLUSIONS: Despite less improvement on ODI, patients enrolled in CSORN, as part of a universal health care system, reported higher rates of satisfaction at 3 months and 1 year post-operatively compared to patients enrolled within a multitier health system.

A Dedicated Orthopaedic Trauma Room Improves Efficiency While Remaining Financially Net Positive.

OBJECTIVES: To determine the impact of dedicated orthopaedic trauma room (DOTR) implementation on operating room efficiency and finances. DESIGN: Retrospective cost-analysis. SETTING: Single midsized academic-affiliated community hospital in Toronto, Canada. PARTICIPANTS: All patients that underwent the most frequently performed orthopaedic trauma procedures (hip hemiarthroplasty, open reduction internal fixation of the ankle, femur, elbow and distal radius), over a 4-year period from 2016 to 2019 were included. INTERVENTION: Patient data acquired for 2 years before the implementation of a DOTR was compared with data acquired for a 2-year period after its implementation, adjusting for the number of cases performed. MAIN OUTCOME MEASUREMENTS: The primary outcome was surgical duration. The secondary outcome was financial impact, including after-hours costs incurred and opportunity cost of displaced elective surgeries. RESULTS: One thousand nine hundred sixty orthopaedic cases were examined pre- and post-DOTR. All procedures had reduced total operative time post-DOTR (mean improvement of 33.4%). The number of daytime operating hours increased 21%, whereas after-hours decreased by 37.8%. Overtime staffing costs were reduced by $24,976 alongside increase in opportunity costs of $22,500. This resulted in a net profit of $2476. CONCLUSIONS: Our results support the premise that DOTRs improve operating room efficiency and can be cost efficient. Our study also specifically addresses the hesitation regarding potential loss of profit from elective surgeries. Widespread implementation can improve patient care while still remaining financially favorable. LEVEL OF EVIDENCE: Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Tracking miR-17-5p Levels following Expression of Seven Reported Target mRNAs.

As the most prominent member of the miR-17-92 cluster, miR-17-5p is well associated with tumorigenesis and cancer progression. It can exert both oncogenic and tumor-suppressive functions by inducing translational repression and/or mRNA decay. The complexity of the tissue-specific expression of the targeted transcripts seems to contribute to the differential functions of miR-17-5p in different types of cancers. In this study, we selected 12 reported miR-17-5p targeting genes with mRNA levels unaffected by miR-17-5p expression and analyzed their expression in 31 organ tissues in transgenic mice by real-time PCR. Surprisingly, miR-17-5p expressing transgenic mice showed a positive correlation in these tissues between miR-17-5p expression levels and the selected miR-17-5p targeted transcripts; with high expression of the miRNA in organs with high selected miRNA-targeted mRNA levels. In cancer cell lines, overexpression of 7 reported miR-17-5p targeted genes' 3'-UTRs promoted miR-17-5p expression; meanwhile, transfection of 3'-UTRs with mutations had no significant effect. Moreover, an increase in AGO2 mRNA was associated with 3'-UTR expression as confirmed by real-time PCR. Hence, miR-17-5p regulation by these target genes might be an alternative mechanism to maintain miR-17-5p expression at tissue-specific levels.

Validation of the Subgroups for Targeted Treatment for Back (STarT Back) screening tool at a tertiary care centre.

BACKGROUND: The Subgroups for Targeted Treatment for Back (STarT Back) tool is a screening questionnaire developed to identify modifiable risk factors for back pain disability in primary care. Given the ability of this tool to assist with early identification of patients at high risk, we examined its concurrent convergent and known-group construct validity in tertiary care. METHODS: This was a case-control study of adult (age > 18 yr) patients with and without an active work-related compensation claim recruited from an academic health centre between August 2017 and May 2019. Patients in the study group were assessed by a physiotherapist and an orthopedic surgeon in a spine specialty program designed to assess and treat workplace injuries. The control group included patients referred to an orthopedic spine surgeon in a publicly funded specialty clinic where an advanced practice physiotherapist determined the need for surgical consultation. We used the Roland-Morris Disability Questionnaire (RMDQ) and the Hospital Anxiety and Depression Scale (HADS) to determine the convergent and known-group construct validity of the STarT Back tool. RESULTS: Fifty case and 50 control participants were included. We observed moderate to high association between the STarT Back total score, psychosocial subscore and risk categories and the RMDQ and HADS scores in the expected direction (p < 0.001). A significant association was observed between risk group allocation and depression (area under the curve values > 80), having a compensable injury and work status (p = 0.002-0.001). CONCLUSION: The STarT Back tool was able to differentiate between patients with and without a compensable injury and patients with different levels of work status. The tool has acceptable convergent and known-group construct validity and can assist in clinical decision-making in a tertiary care setting where adjunct psychologic management may be indicated.

Detection of SARS-CoV-2 contamination in the operating room and birthing room setting: a cross-sectional study.

BACKGROUND: The exposure risks to front-line health care workers caring for patients with SARS-CoV-2 infection undergoing surgery or obstetric delivery are unclear, and an understanding of sample types that may harbour virus is important for evaluating risk. We sought to determine whether SARS-CoV-2 viral RNA from patients with SARS-CoV-2 infection undergoing surgery or obstetric delivery was present in the peritoneal cavity of male and female patients, in the female reproductive tract, in the environment of the surgery or delivery suite (surgical instruments or equipment used, air or floors), and inside the masks of the attending health care workers. METHODS: We conducted a cross-sectional study from November 2020 to May 2021 at 2 tertiary academic Toronto hospitals, during urgent surgeries or obstetric deliveries for patients with SARS-CoV-2 infection. The presence of SARS-CoV-2 viral RNA in patient, environmental and air samples was identified by real-time reverse transcription polymerase chain reaction (RT-PCR). Air samples were collected using both active and passive sampling techniques. The primary outcome was the proportion of health care workers' masks positive for SARS-CoV-2 RNA. We included adult patients with positive RT-PCR nasal swab undergoing obstetric delivery or urgent surgery (from across all surgical specialties). RESULTS: A total of 32 patients (age 20-88 yr) were included. Nine patients had obstetric deliveries (6 cesarean deliveries), and 23 patients (14 male) required urgent surgery from the orthopedic or trauma, general surgery, burn, plastic surgery, cardiac surgery, neurosurgery, vascular surgery, gastroenterology and gynecologic oncology divisions. SARS-CoV-2 RNA was detected in 20 of 332 (6%) patient and environmental samples collected: 4 of 24 (17%) patient samples, 5 of 60 (8%) floor samples, 1 of 54 (2%) air samples, 10 of 23 (43%) surgical instrument or equipment samples, 0 of 24 cautery filter samples and 0 of 143 (95% confidence interval 0-0.026) inner surface of mask samples. INTERPRETATION: During the study period of November 2020 to May 2021, we found evidence of SARS-CoV-2 RNA in a small but important number of samples obtained in the surgical and obstetric operative environment. The finding of no detectable virus inside the masks worn by the health care teams would suggest a low risk of infection for health care workers using appropriate personal protective equipment.

Perspective on the integration of optical sensing into orthopedic surgical devices.

SIGNIFICANCE: Orthopedic surgery currently comprises over 1.5 million cases annually in the United States alone and is growing rapidly with aging populations. Emerging optical sensing techniques promise fewer side effects with new, more effective approaches aimed at improving patient outcomes following orthopedic surgery. AIM: The aim of this perspective paper is to outline potential applications where fiberoptic-based approaches can complement ongoing development of minimally invasive surgical procedures for use in orthopedic applications. APPROACH: Several procedures involving orthopedic and spinal surgery, along with the clinical challenge associated with each, are considered. The current and potential applications of optical sensing within these procedures are discussed and future opportunities, challenges, and competing technologies are presented for each surgical application. RESULTS: Strong research efforts involving sensor miniaturization and integration of optics into existing surgical devices, including K-wires and cranial perforators, provided the impetus for this perspective analysis. These advances have made it possible to envision a next-generation set of devices that can be rigorously evaluated in controlled clinical trials to become routine tools for orthopedic surgery. CONCLUSIONS: Integration of optical devices into surgical drills and burrs to discern bone/tissue interfaces could be used to reduce complication rates across a spectrum of orthopedic surgery procedures or to aid less-experienced surgeons in complex techniques, such as laminoplasty or osteotomy. These developments present both opportunities and challenges for the biomedical optics community.

Undoing structural racism in dentistry: Advocacy for dental therapy.

Like other areas of health, structural racism has a deep impact on oral health and is a key driver of racial inequities in access to care and outcomes. Racism also structures the relationship between oral health and access to economic opportunities. As a result, communities of color, American Indian/Alaska Native (AI/AN) communities, and low-income populations experience the highest rates of the health, social, and economic costs of dental disease. This is compounded by issues of community-level dental fear/trauma resulting from receiving itinerate care. Dentistry has long struggled to equitably distribute care and diversify its overwhelmingly white and affluent workforce, resulting in many communities not having access to providers who represent their identity and/or live in their community. While multi-generational lack of access to dental care is not unique to Alaska, Alaska Native communities are the home to a reimagined, community-centered care delivery system that is improving health outcomes. For almost two decades, AI/AN leaders have recruited and trained community members to serve as dental therapists-dental team members who offer routine and preventive care responsive to local geographic and cultural/community norms. As members of the communities they serve, dental therapists are fluent in the language and cultural norms of their patients, improving patient-provider trust, access to care, and oral health outcomes. The communities that dental therapists serve are also now investing money and training in their community members, building educational opportunities, and professional wage jobs and directly countering the economic impact structural racism has on oral health.

Nanopillar Templating Augments the Stiffness and Strength in Biopolymer Films.

Natural load-bearing mammalian tissues, such as cartilage and ligaments, contain ∼70% water yet can be mechanically stiff and strong due to the highly templated structures within. Here, we present a bioinspired approach to significantly stiffen and strengthen biopolymer hydrogels and films through the combination of nanoscale architecture and templated microstructure. Imprinted submicrometer pillar arrays absorb energy and deflect cracks. The produced chitosan hydrogels show nanofiber chains aligned by nanopillar topography, subsequently templating the microstructure throughout the film. These templated nanopillar chitosan hydrogels mechanically outperform unstructured flat hydrogels, with increases in the moduli of ∼160%, up to ∼20 MPa, and work at break of ∼450%, up to 8.5 MJ m-3. Furthermore, the strength at break increases by ∼350%, up to ∼37 MPa, and it is one of the strongest hydrogels yet reported. The nanopillar templating strategy is generalizable to other biopolymers capable of forming oriented domains and strong interactions. Overall, this process yields hydrogel films that demonstrate mechanical performance comparable to that of other stiff, strong hydrogels and natural tissues.

Promotion of tumor progression by exosome transmission of circular RNA circSKA3.

We performed in vitro and in vivo experiments to investigate the role of the circular RNA circSKA3 in tumor development. We examined the effects of circSKA3 on mediating breast cancer metastasis. In vitro, we found that the circular RNA circSKA3 was transferred between breast cancer cells, which were decreased by inhibiting exosome secretion. In vivo, circSKA3-containing exosomes potentiated tumor development and invasion that were inhibited by blocking exosome transmission. The ascites isolated from tumor-bearing mice or breast cancer patients showed high levels of circSKA3 and integrin ß1. Single-cell culture and single-cell PCR showed that circSKA3 was heterogeneously expressed, the cells expressing higher levels of circSKA3 had a higher potential to form large colonies. This property was similar to c-myc, but circSKA3 expression had no correlation with c-myc levels. The effects of circSKA3 on cell migration and invasion appeared to predominate c-myc functions. By releasing circSKA3-containing exosomes to cancer cells expressing lower levels of circSKA3, the large colonies could regulate the activities of small colonies, enhancing the tumor-forming capacity of the entire population. Thus, we provide evidence that the transmission of circular RNAs in tumor-derived exosomes may allow for the maintenance of advantageous invasive sub-clones in breast cancer.

Femoral Antegrade Starting Tool (FAST) for intramedullary nailing.

Intramedullary (IM) nailing is the standard of care for adult lower extremity long bone fracture stabilisation. Key to this procedure is obtaining the correct entry point and trajectory for initial guide pin insertion. This work presents the Femoral Antegrade Starting Tool (FAST), a surgical tool that addresses the lack of connectivity in utilising sequential 2D fluoroscopic images to achieve 3D alignment of femoral guide pin placement. The user centred design and development of FAST is introduced and the performance of this device evaluated during guide pin insertion for femoral IM nailing in a series of sawbones and cadaveric models leading to a first in human clinical cohort study. The results demonstrated the potential of FAST to improve time and consistency of the guide pin insertion for femoral IM nailing for less experienced surgeons and trainees. Overall, FAST was found to be easy to use with a high degree of clinical interest (particularly for use in large patients) and acceptance motivating continued development of this new technology.