bluuebunny/crossref_metadata_2025 huggingface dataset:
High Prevalence of Macrolide and Fluoroquinolone Resistance–Mediating Mutations in Mycoplasma genitalium–Positive Urine Specimens From Saskatchewan
Authors: Parmar Nidhi R. , Mushanski Linda , Wanlin Tasker , Lepe Aurora , Lang Amanda , Minion Jessica , Dillon Jo-Anne R.
Published: August 2021

Background

Mycoplasma genitalium is an emerging, sexually transmitted infection, which is more prevalent than Chlamydia trachomatis in some regions. An increase in antibiotic resistance, that is, azithromycin and moxifloxacin, recommended for treating M. genitalium infections has been noted. This is the first detailed report on the prevalence of M. genitalium and its antimicrobial resistance in Saskatchewan, Canada.

Methods

Aptima urine specimens (n = 1977), collected for the diagnosis of C. trachomatis/Neisseria gonorrhoeae, were tested for M. genitalium using the Aptima M. genitalium assay (MG-TMA). Antimicrobial resistance was ascertained using polymerase chain reaction and DNA sequencing of 23S rRNA (azithromycin) and parC (moxifloxacin) from Aptima M. genitalium assay–positive specimens; mutations predictive of resistance were noted.

Results

The prevalence of M. genitalium was 9.6% (189/1977). Predicted resistance to azithromycin (substitutions at positions 2058/2059 in 23S rRNA) was observed in 63.6% (70/110) of the specimens tested, whereas resistance to moxifloxacin (S83I in ParC) was observed in 10.6% (9/85) of the specimens. Mutations in both 23S rRNA and ParC were observed in 2.12% (4/189) of the specimens. Women aged 20 to 24 years had the highest prevalence (18.3%, P < 0.001), and in females, M. genitalium was significantly associated with C. trachomatis or N. gonorrhoeae/C. trachomatis (P < 0.001) coinfection. The prevalence of M. genitalium (9.6%) in the province of Saskatchewan was higher than that of the other 2 bacterial sexually transmitted infections (N. gonorrhoeae (3.09%) and C. trachomatis (6.85%).

Conclusions

The prevalence of M. genitalium (9.6%) and associated resistance to azithromycin (63.6%) in Saskatchewan high, suggesting that empiric azithromycin therapy may not be adequate for treating M. genitalium infections.
Comparison of Postoperative Occupational Therapy and Narcotic Use in Two Carpometacarpal Arthroplasty Approaches
Authors: Sarac Nikolas , Samade Richard , Jain Sonu A.
Published: August 2021

Background:

The authors sought to determine whether differences exist in (1) the number of postoperative occupational therapy visits and (2) narcotic use in two carpometacarpal arthroplasty groups.

Methods:

A retrospective study comparing patients undergoing abductor pollicis longus (APL) suspensionplasty (154 patients) or flexor carpi radialis ligament reconstruction and tendon interposition (FCR LRTI) techniques (40 patients) between January 1, 2012, and August 1, 2018, was performed. Data included demographics, procedure performed, complications, number of postoperative occupational therapy visits, and postoperative morphine equivalent dosage used. Statistical testing used the chi-square test for proportions and the Wilcoxon-Mann-Whitney test for nonnormal data. The significance level was 0.05.

Results:

The APL suspensionplasty and FCR LRTI groups had similar ages (58.1 ± 7.8 years versus 58.1 ± 7.7 years), sex ratios (73 percent female versus 75 percent female), and preoperative narcotic user proportions (1 percent versus 3 percent). Complication rates following the procedures were similar (21 percent and 18 percent, respectively). The number of postoperative occupational therapy visits following APL suspensionplasty (median, 0; interquartile range, 0 to 4) and FCR LRTI (median, 0; interquartile range, 0 to 4) were not significantly different (p = 0.961). There was less use of narcotics following APL suspensionplasty (median, 375 morphine equivalent dosage; interquartile range, 241.9 to 525 morphine equivalent dosage) compared with FCR LRTI (median, 462.5 morphine equivalent dosage; interquartile range, 375 to 768.8 morphine equivalent dosage), and this difference was significant (p = 0.0007).

Conclusions:

The APL suspensionplasty technique had less narcotic use and similar complication rates and occupational therapy visits compared to FCR LRTI. Prospective studies comparing postoperative pain control and function with these two carpometacarpal arthroplasty techniques may be beneficial.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
Targeted Muscle Reinnervation Improves Pain and Ambulation Outcomes in Highly Comorbid Amputees
Authors: Chang Brian L. , Mondshine Josh , Attinger Christopher E. , Kleiber Grant M.
Published: August 2021

Background:

Approximately 200,000 people undergo a lower extremity amputation each year. Following amputation, patients suffer from chronic pain, inability to ambulate, and high mortality rates. Targeted muscle reinnervation is a nerve transfer procedure that redirects transected sensory and mixed nerves into motor nerves to treat neuroma and phantom limb pain. This study evaluates outcomes with prophylactic targeted muscle reinnervation at the time of below-knee amputation.

Methods:

This is a cohort study comparing 100 patients undergoing below-knee amputation with primary targeted muscle reinnervation and 100 patients undergoing below-knee amputation with standard traction neurectomy and muscle implantation. Outcome metrics included the presence of residual and phantom limb pain, pain severity, opioid use, ambulation ability, and mortality rates.

Results:

The targeted muscle reinnervation group was on average 60 years old with a body mass index of 29 kg/m2. Eighty-four percent had diabetes, 55 percent had peripheral vascular disease, and 43 percent had end-stage renal disease. Average follow-up was 9.6 months for the targeted muscle reinnervation group and 18.5 months for the nontargeted muscle reinnervation group. Seventy-one percent of targeted muscle reinnervation patients were pain free, compared with 36 percent (p < 0.01). Fourteen percent of targeted muscle reinnervation patients had residual limb pain, compared with 57 percent (p < 0.01). Nineteen percent of targeted muscle reinnervation patients had phantom limb pain, compared with 47 percent (p < 0.01). Six percent of targeted muscle reinnervation patients were on opioids, compared with 26 percent (p < 0.01); and 90.9 percent of targeted muscle reinnervation patients were ambulatory, compared with 70.5 percent (p < 0.01).

Conclusion:

Targeted muscle reinnervation reduces pain and improves ambulation in patients undergoing below-knee amputation, which may be critical in improving morbidity and mortality rates in this comorbid patient population.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
Nerve Coaptation Improves the Sensory Recovery of the Breast in DIEP Flap Breast Reconstruction
Authors: Beugels Jop , Bijkerk Ennie , Lataster Arno , Heuts Esther M. , van der Hulst René R. W. J. , Tuinder Stefania M. H.
Published: August 2021

Background:

Restoring the sensation of the reconstructed breast has increasingly become a goal of autologous breast reconstruction. The aim of this study was to analyze the sensory recovery of the breast and donor site of innervated compared to noninnervated deep inferior epigastric perforator (DIEP) flap breast reconstructions, to assess associated factors, and to compare the differences between preoperative and postoperative sensation.

Methods:

A prospective cohort study was conducted, including patients who underwent innervated or noninnervated DIEP flap breast reconstruction between August of 2016 and August of 2018. Nerve coaptation was performed to the anterior cutaneous branch of the third intercostal nerve. Preoperative and postoperative sensory testing of the breast and donor site was performed with Semmes-Weinstein monofilaments.

Results:

A total of 67 patients with 94 innervated DIEP flaps and 58 patients with 80 noninnervated DIEP flaps were included. Nerve coaptation was significantly associated with lower mean monofilament values for the breast (−0.48; p < 0.001), whereas no significant differences were found for the donor site (−0.16; p = 0.161) of innervated compared to noninnervated DIEP flaps. Factors positively or negatively associated with sensory recovery of the breast and donor site were identified. Preoperative versus postoperative comparison demonstrated significantly superior sensory recovery of the breast in innervated flaps (adjusted difference, −0.48; p = 0.017).

Conclusions:

This study demonstrated that nerve coaptation in DIEP flap breast reconstruction significantly improved the sensory recovery of the breast compared to noninnervated flaps. The sensory recovery of the donor site was not compromised in innervated reconstructions. The results support the role of nerve coaptation in autologous breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, II.
Change in Rheologic Properties of Facial Soft-Tissue Fillers across the Physiologic Angular Frequency Spectrum
Authors: Cotofana Sebastian , Hamade Hassan , Bertucci Vince , Fagien Steven , Green Jeremy B. , Pavicic Tatjana , Nikolis Andreas , Lachman Nirusha , Hadjab Abdelbasste , Frank Konstantin
Published: August 2021

Background:

The number of soft-tissue filler injections performed in the United States is constantly increasing and reflects the high demand for enhanced facial and body attractiveness. The objective of the present study was to measure the viscoelastic properties of soft-tissue fillers when subjected to different testing frequencies. The range of tested frequencies represents clinically different facial areas with more [lips (high frequency)] or less [zygomatic arch (low frequency)] soft-tissue movement.

Methods:

A total of 35 randomly selected hyaluronic acid–based dermal filler products were tested in an independent laboratory for their values of G′, G″, tan δ, and G* at angular frequencies between 0.1 and 100 radian/second.

Results:

The results of the objective analyses revealed that the viscoelastic properties of all tested products changed between 0.1 and 100 radian/second angular frequency. Changes in G′ ranged from 48.5 to 3116 percent, representing an increase in their initial elastic modulus, whereas changes in G″ ranged from −53.3 percent (i.e., decrease in G″) to 7741 percent (i.e., increase in G″), indicating both an increase and a decrease in their fluidity, respectively.

Conclusions:

The increase in G′ would indicate the transition from a “softer” to a “harder” filler, and the observed decrease in G″ would indicate an increase in the filler’s “fluidity.” Changes in the frequency of applied shear forces such as those occurring in the medial versus the lateral face will influence the aesthetic outcome of soft-tissue filler injections.
What Is the Impact of Postoperative Antibiotic Prophylaxis on Tissue Expander Infection Rates in Pediatric Patients?
Authors: Wang Howard D. , Cho Annie , Quan Amy , Ibrahim Zuhaib , Yang Robin , Steinberg Jordan P. , Redett Richard J.
Published: August 2021

Background:

Tissue expansion in the pediatric population can be complicated by high rates of infection and extrusion. The aim of this study was to examine the impact of postoperative antibiotic prophylaxis on infectious complications.

Methods:

A retrospective study of all pediatric patients who underwent tissue expander insertion at a children’s hospital over a 12-year period was performed. Predictor variables included age, sex, race, indication, anatomical location, number of expanders inserted, serial expansion, history of infection or extrusion, and postoperative antibiotics. Outcome variables included infection and extrusion. Bivariate and multivariate analyses were performed to identify factors associated with infection and/or extrusion.

Results:

A total of 180 patients who underwent 317 operations for tissue expander insertion were included in this study. Postoperative infection and/or extrusion occurred after 73 operations (23 percent). Postoperative prophylactic antibiotics were prescribed after 232 operations (75 percent), and only perioperative (≤24 hours) antibiotics were administered in 85 cases (25 percent). There were no significant differences in the rate of infection (12.1 percent versus 8.9 percent; p = 0.46), extrusion (16.8 percent versus 17.7 percent; p = 0.88), or infection and/or extrusion (23.7 percent versus 24.1 percent; p = 0.95) between these two groups. Multivariate analysis revealed that postoperative antibiotics did not have a significant association with infection and/or extrusion (OR, 0.84; 95 percent CI, 0.44 to 1.63; p = 0.61).

Conclusions:

The rates of infection/extrusion were similar between pediatric patients who received only perioperative antibiotics (≤24 hours) and those who were prescribed a course of postoperative antibiotics. Based on these results, a course of postoperative prophylactic antibiotics may be unnecessary after insertion of tissue expanders in pediatric patients.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
A Randomized Controlled Trial of Virtual Reality in Awake Minor Pediatric Plastic Surgery Procedures
Authors: Clerc Paul G. B. , Arneja Jugpal S. , Zwimpfer Charlotte M. , Behboudi Amir , Goldman Ran D.
Published: August 2021

Background:

Virtual reality has been used to alleviate pain and anxiety in a variety of medical procedures. The authors sought to explore the effects of virtual reality in common awake minor plastic surgery procedures where children may experience discomfort.

Methods:

A randomized controlled trial compared virtual reality to standard-of-care distraction among children aged 6 to 16 years undergoing awake minor plastic surgery procedures at a quaternary children’s hospital. Primary outcome was change in Faces Pain Scale–Revised pain score, and secondary outcomes included change in Venham Situational Anxiety Scale score, procedure duration, administration of local anesthetic, and pain/anxiety management satisfaction.

Results:

Mean pain and anxiety scores were similar in both groups (p = 0.60 and p = 0.18, respectively), and procedure duration was shorter with virtual reality (22 minutes versus 29 minutes; p = 0.002). Duration remained shorter in a linear regression model accounting for procedure type (p = 0.01). Similar proportions of children received additional local anesthetic after the initial dose (virtual reality, n = 6; standard of care, n = 9; p = 0.19) and median pain management satisfaction was similar (virtual reality, 9 of 10; standard of care, 9 of 10; p = 0.41). Median anxiety management satisfaction was similar (virtual reality, 9 of 10; standard of care, 9 of 10; p = 0.05). Younger children reported more “fun” than older children with virtual reality (p = 0.02). Surgeons reported interest “using virtual reality again” in 83 percent of cases.

Conclusions:

The use of virtual reality for awake pediatric plastic surgery reduced procedure time but not pain or anxiety compared to standard of care in children aged 6 to 16 years. Virtual reality was safe and well-liked and should be considered as an additional tool. Increased efficiency may allow more cases to be performed.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, II.
Management of Calcified Cephalohematoma of Infancy: The University of Michigan 25-Year Experience
Authors: Ulma Raquel M. , Sacks Gina , Rodoni Bridger M. , Duncan Anthony , Buchman Alexandra T. , Buchman Brevin C. , Vercler Christian J. , Kasten Steven J. , Muraszko Karin M. , Buchman Steven R.
Published: August 2021

Background:

Cephalohematoma of infancy is the result of a subperiosteal blood collection that usually forms during birth-related trauma. A small proportion of cephalohematomas can calcify over time, causing a permanent calvarial deformity that is only correctable with surgery. The authors present a technique for the excision and reconstruction of calcified cephalohematoma and their management experience over the past 25 years.

Methods:

All patients with a diagnosis of calcified cephalohematoma between 1994 and 2019 were identified. Patients were included if the diagnosis was confirmed by a pediatric plastic surgeon or a neurosurgeon. All patients underwent surgical evaluation followed by surgical intervention or observation. Patient demographics and potential risk factors for both surgical and nonsurgical groups were compared using chi-square or Fisher’s exact test. Additional data were collected for the surgical cohort.

Results:

Of 160 infants diagnosed with cephalohematoma, 72 met inclusion criteria. Thirty patients underwent surgical treatment. There was no significant difference in demographics, baseline characteristics, or potential risk factors between the operative and nonoperative groups. Mean age at the time of surgery was 8.6 months. Twenty-one surgical patients (70 percent) required inlay bone grafting. All surgery patients had improvement in calvarial shape. The main risk of surgery was blood loss requiring transfusion [eight patients (26.7 percent)]. Thirteen percent of patients experienced minor complications.

Conclusions:

This series of 72 children with calcified cephalohematomas, 30 of whom required surgical intervention, is one of the largest to date. The technique presented herein demonstrated excellent surgical outcomes by restoring normal cranial contours and was associated with a low complication profile.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, IV.
Improving Ischemic Stroke Care With MRI and Deep Learning Artificial Intelligence
Authors: Yu Yannan , Heit Jeremy J. , Zaharchuk Greg
Published: August 2021

Advanced magnetic resonance imaging has been used as selection criteria for both acute ischemic stroke treatment and secondary prevention. The use of artificial intelligence, and in particular, deep learning, to synthesize large amounts of data and to understand better how clinical and imaging data can be leveraged to improve stroke care promises a new era of stroke care. In this article, we review common deep learning model structures for stroke imaging, evaluation metrics for model performance, and studies that investigated deep learning application in acute ischemic stroke care and secondary prevention.
Quantitative Evaluation of Palatal Lengthening After Cleft Palate Repair When a Buccal Flap Is Routinely Combined With Furlow's Z-Plasty
Authors: Aboulhassan Mamdouh Ahmed , Aly Tarek Mahmoud , Akram khodir Mahmoud Mohamed , Moussa Hassan Mahmoud , Hussein Mohammed Ahmed
Published: August 2021

Introduction

The use of a buccinator myomucosal flap in combination with Furlow's Z-plasty during primary and secondary palatal repairs has been proposed by many authors to overcome some of the limitations of Furlow's technique. However, there have been no studies that quantitatively measured the effective palatal lengthening when the buccal flap is added.

Patients and Methods

The buccal flap is routinely used during primary palate repair in order to fill the gap between the hard palate and reoriented palatal muscle sling. The soft palatal length was measured in the midline from the posterior edge of the hard palate to the base of the uvula. All patients were measured before starting the surgery and just after palatal closure in the standard position for cleft palate repair.

Results

Seventy-three patients with cleft palate who were candidates for primary repair were included. The mean age at the time of operation was 11.4 ± 3.5 months. The mean preoperative palatal length was 21.36 ± 3.529 mm, whereas the mean postoperative palatal length was 29.64 ± 4.171) mm. The mean palatal length change was 8.29 ± 2.514 mm (P < 0.000).

Conclusions

The Combined use of a buccinator myomucosal flap with modified Furlow's Z-plasty in primary cleft palate repair has proven effective for palatal lengthening and achieved tensionless closure without the need for relaxing incision. It also provided a pliable soft tissue attachment of the palatal muscles to the hard palate allowing for better muscle function and mobility.
Recommendations and Guidelines for the Use of Simulation to Address Structural Racism and Implicit Bias
Authors: Vora Samreen , Dahlen Brittany , Adler Mark , Kessler David O. , Jones V. Faye , Kimble Shelita , Calhoun Aaron
Published: August 2021

Summary Statement

Simulation-based education is a particularly germane strategy for addressing the difficult topic of racism and implicit bias due to its immersive nature and the paradigm of structured debriefing. Researchers have proposed actionable frameworks for implicit bias education, particularly outlining the need to shift from recognition to transformation, with the goal of changing discriminatory behaviors and policies. As simulation educators tasked with training health care professionals, we have an opportunity to meet this need for transformation. Simulation can shift behaviors, but missteps in design and implementation when used to address implicit bias can also lead to negative outcomes. The focus of this article is to provide recommendations to consider when designing simulation-based education to specifically address racism and implicit bias.
Sulfasalazine-Induced Toxic Epidermal Necrolysis
Authors: Shahidi-Dadras Mohammad , Shahrigharahkoshan Shaghayegh , Yazdi Esmat , Fatemi Alireza , Mahboubi-Fooladi Zahra , Dadkhahfar Sahar
Published: August 2021

COVID-19 is a major health issue, and patients with underlying conditions are more susceptible to catastrophic outcomes. Toxic epidermal necrolysis (TEN) is a severe systemic disease caused by an immune system hypersensitive reaction. We present a case of TEN induced following sulfasalazine administration that later on complicated with COVID-19, deep vein thrombosis, pulmonary emboli, and eventually death.
Something's “Fishy” With That Sore Throat...
Authors: Sweeney Michael , Ramponi Denise R.
Published: August 2021

A 9-year old male presented to the emergency department for the evaluation of a sore throat. Initial history of present illness stated in the triage note was that “the child complained of a sore throat,” suggesting possible pharyngitis. There was no evidence of stridor, sialorrhea, hypoxia, or aphonia. Further investigation of the history of present illness identified the concern for a possible esophageal foreign body. Imaging studies of the neck identified a fishbone in the esophagus. This case presentation discusses an atypical presentation of an esophageal foreign body and the subtle findings on assessment and imaging. This case highlights the importance of illiciting a history of present illness and the subtleties of esophageal foreign body identification.
The Effect of a Nurse Initiated Therapeutic Conversation Compared to Standard Care for Patients With Acute Pain in the ED
Authors: Shillington Kelly , Thompson Cameron , Saraga Stephanie , Soch Laura , Asomaning Nana , Borgundvaag Bjug , McLeod Shelley L.
Published: August 2021

Acute pain is a common presenting complaint in the emergency department (ED) and is most often treated with opioid or nonopioid analgesia. However, studies have shown that receiving analgesia alone does not always influence patient satisfaction with pain management in the ED. Pain anxiety and catastrophizing have been shown to affect pain intensity and patients' response to analgesia. The objective of this study was to determine whether a brief therapeutic conversation would improve patient satisfaction with pain management compared with standard care for adult patients presenting to the ED with moderate to severe acute pain. Adult (18 years or older) patients presenting to the ED with moderate to severe acute pain were randomized to either the standard care group or the intervention group. Patients in the intervention group participated in a brief therapeutic conversation with an ED nurse to discuss their perceived cause of pain, level of anxiety, and expectations of their pain management. Prior to discharge, all patients were asked to complete a self-reported, 9-item questionnaire to assess their level of satisfaction with their overall ED experience. A total of 166 patients (83 in each group) were enrolled. Patient satisfaction with ED pain management and the proportion of patients who received analgesia in the ED were similar in both the control (n = 57; 68.7%) and intervention (n = 58; 69.9%) groups (Δ 1.2%; 95% CI [12.6, 15]). Qualitative findings demonstrate that patients place high importance on acknowledgment from ED staff and worry about the unknown cause of pain. This study suggests that patient satisfaction with pain management in the ED is multifactorial and complex. Further research should investigate additional methods of integrating nurse-led interventions into the care of patients in acute pain.
The Efficacy of Lavender Aromatherapy in Reducing the Overcrowding-Related Anxiety in Health Care Workers
Authors: Şimşek Perihan , Çilingir Dilek
Published: August 2021

In general, emergency departments (EDs) are stressful workplaces with excessive workloads and time pressures. Crowding, which is an important problem worldwide disrupting ED functions, leads further increases in the stressors which health care workers are exposed to. Long-term exposure to stressors can lead to anxiety in health care workers. The aim of this study was to determine the effect of aromatherapy on crowding-related anxiety in ED health care workers. Crowding was measured simultaneously with the National Emergency Department Overcrowding Scale objectively and the Health Care Workers' Crowding Perception Evaluation Form subjectively. The state–trait anxiety level was measured at each crowding level according to the health care workers' perception. When perceived crowding was at severely overcrowding level, lavender oil aromatherapy was applied. Anxiety level was measured before and after aromatherapy. Aromatherapy was repeated 3 times on different days. A significant positive correlation was found between state anxiety level and perceived crowding (r = 0.415, p < 0.001). Aromatherapy was found to have a significant correlation in reducing the overcrowding-related anxiety in health care workers (p < 0.05). This study showed that there is a significant correlation between anxiety level and perceived crowding, and aromatherapy is related to a decrease in overcrowding-related anxiety. In EDs, lavender oil aromatherapy can be used as a complementary method in reducing the overcrowding-related anxiety. But further researches are needed to verify that aromatherapy has a causative effect on reducing overcrowding-related anxiety.
The representational hierarchy in human and artificial visual systems in the presence of object-scene regularities
Authors: Bracci Stefania , Mraz Jakob , Zeman Astrid , Leys Gaëlle , de Beeck Hans Op
Published: August 2021

Human vision is still largely unexplained. Computer vision made impressive progress on this front, but it is still unclear to which extent artificial neural networks approximate human object vision at the behavioral and neural levels. Here, we investigated whether machine object vision mimics the representational hierarchy of human object vision with an experimental design that allows testing within-domain representations for animals and scenes, as well as across-domain representations reflecting their real-world contextual regularities such as animal-scene pairs that often co-occur in the visual environment. We found that DCNNs trained in object recognition acquire representations, in their late processing stage, that closely capture human conceptual judgements about the co-occurrence of animals and their typical scenes. Likewise, the DCNNs representational hierarchy shows surprising similarities with the representational transformations emerging in domain-specific ventrotemporal areas up to domain-general frontoparietal areas. Despite these remarkable similarities, the underlying information processing differs. The ability of neural networks to learn a human-like high-level conceptual representation of object-scene co-occurrence depends upon the amount of object-scene co-occurrence present in the image set thus highlighting the fundamental role of training history. Further, although mid/high-level DCNN layers represent the category division for animals and scenes as observed in VTC, its information content shows reduced domain-specific representational richness. To conclude, by testing within- and between-domain selectivity while manipulating contextual regularities we reveal unknown similarities and differences in the information processing strategies employed by human and artificial visual systems.

Author Summary

Computational object vision represents the new frontier of brain models, but do current artificial visual systems known as deep convolutional neural networks (DCNNs) represent the world as humans do? Our results reveal that DCNNs are able to capture important representational aspects of human vision both at the behavioral and neural levels. At the behavioral level, DCNNs are able to pick up contextual regularities of objects and scenes thus mimicking human high-level semantic knowledge such as learning that a polar bear “lives” in ice landscapes. At the neural representational level, DCNNs capture the representational hierarchy observed in the visual cortex all the way up to frontoparietal areas. Despite these remarkable correspondences, the information processing strategies implemented differ. In order to aim for future DCNNs to perceive the world as humans do, we suggest the need to consider aspects of training and tasks that more closely match the wide computational role of human object vision over and above object recognition.
Can foot placement during gait be trained? Adaptations in stability control when ankle moments are constrained
Authors: Hoogstad L.A. , van Leeuwen A.M. , van Dieën J.H. , Bruijn S.M.
Published: August 2021

Accurate coordination of mediolateral foot placement, relative to the center of mass kinematic state, is one of the mechanisms which ensures mediolateral stability during human walking. Previously, we found that shoes constraining ankle moments decreased the degree of foot placement control with respect to the center of mass kinematic state. As such, ankle moment constraints can be seen as a perturbation of foot placement. Direct mechanical perturbations of the swing leg trajectory can improve the degree of foot placement control as an after-effect. Here, we asked whether constrained ankle moments could have a similar effect. If confirmed, this would offer a simple training tool for individuals with impaired foot placement control. Participants walked in three conditions; normal (baseline) while wearing shoes constraining ankle moments (training) and normal again (after-effects). The degree of foot placement control was calculated as the percentage of variance in foot placement that could be predicted based on the center of mass kinematic state in the preceding swing phase. During training, the degree of foot placement control decreased initially compared to baseline, but it gradually improved over time. In the after-effect condition, it was higher than during baseline, yet not significantly so. During training, we observed increased step width, decreased stride time and reduced local dynamic stability. In conclusion, constraining ankle moment control deteriorates the degree of foot placement control. A non-significant trend towards an improved degree of foot placement control after prolonged exposure to constrained ankle moments, allows for speculation on a training potential.
Inference and Validation of the Structure of Lotka-Volterra Models
Authors: Voit Eberhard O. , Davis Jacob D. , Olivença Daniel V.
Published: August 2021

For close to a century, Lotka-Volterra (LV) models have been used to investigate interactions among populations of different species. For a few species, these investigations are straightforward. However, with the arrival of large and complex microbiomes, unprecedently rich data have become available and await analysis. In particular, these data require us to ask which microbial populations of a mixed community affect other populations, whether these influences are activating or inhibiting and how the interactions change over time. Here we present two new inference strategies for interaction parameters that are based on a new algebraic LV inference (ALVI) method. One strategy uses different survivor profiles of communities grown under similar conditions, while the other pertains to time series data. In addition, we address the question of whether observation data are compliant with the LV structure or require a richer modeling format.

The code and data used in this manuscript are available at “https://github.com/LBSA-VoitLab/Inference_and_Validation_of_the_Structure_of_Lotka_Volterra_Models“.
Integration of transcriptomics and network analysis reveals co-expressed genes in Frankliniella occidentalis guts that respond to tomato spotted wilt virus infection
Authors: Han Jinlong , Rotenberg Dorith
Published: August 2021

Background

The arthropod gut is the first barrier to infection by viruses that are internally borne and transmitted persistently by arthropod vectors to plant and animal hosts. Tomato spotted wilt virus (TSWV), a plant-pathogenic virus, is transmitted exclusively by thrips vectors in a circulative-propagative manner. Frankliniella occidentalis (western flower thrips), the principal thrips vector of TSWV, is transmission-competent only if the virus is acquired by young larvae. To begin to understand the larval gut response to TSWV infection and accumulation, a genome- assisted, transcriptomic analysis of F. occidentalis gut tissues of first (early L1) and second (early L2 and late L2) instar larvae was conducted using RNA-Seq to identify differentially-expressed transcripts (DETs) in response to TSWV compared to non- exposed cohorts.

Results

The larval gut responded in a developmental stage-dependent manner, with the majority of DETs (71%) associated with the early L1 stage at a time when virus infection is limited to the midgut epithelium. Provisional annotations of these DETs inferred roles in digestion and absorption, insect innate immunity, and detoxification. Weighted gene co-expression network analysis using all assembled transcripts of the gut transcriptome revealed eight gene modules that distinguish the larval development. Intra-module interaction network analysis of three most DET- enriched modules revealed ten central hub genes. Droplet digital PCR-expression analyses of select network hub and connecting genes revealed temporally-dynamic changes in gut expression during and post exposure to TSWV.

Conclusion

These findings expand our understanding of the developmentally-mediated interaction between thrips vectors and orthotospoviruses, and provide opportunities for probing pathways for biomarkers of thrips vector competence.
Crosstalk between myosin II and formin functions in the regulation of force generation and actomyosin dynamics in stress fibers
Authors: Nishimura Yukako , Shi Shidong , Li Qingsen , Bershadsky Alexander D. , Viasnoff Virgile
Published: August 2021

REF52 fibroblasts have a well-developed contractile machinery, the most prominent elements of which are actomyosin stress fibers with highly ordered organization of actin and myosin IIA filaments. The relationship between contractile activity and turnover dynamics of stress fibers is not sufficiently understood. Here, we simultaneously measured the forces exerted by stress fibers (using traction force microscopy or micropillar array sensors) and the dynamics of actin and myosin (using photoconversion-based monitoring of actin incorporation and high-resolution fluorescence microscopy of myosin II light chain). Our data revealed new features of the crosstalk between myosin II-driven contractility and stress fiber dynamics. During normal stress fiber turnover, actin incorporated all along the stress fibers and not only at focal adhesions. Incorporation of actin into stress fibers/focal adhesions, as well as actin and myosin II filaments flow along stress fibers, strongly depends on myosin II activity. Myosin II-dependent generation of traction forces does not depend on incorporation of actin into stress fibers per se, but still requires formin activity. This previously overlooked function of formins in maintenance of the actin cytoskeleton connectivity could be the main mechanism of formin involvement in traction force generation.

Highlights

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Cell traction forces are measured together with visualization of actomyosin flow

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Actin turnover depends on formin and myosin II activities

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Traction forces depend not only on myosin II, but also on formins

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Traction force generation may require formin-dependent cytoskeleton connectivity
Niche theory for within-host parasite dynamics: Analogies to food web modules via feedback loops
Authors: Ramesh Ashwini , Hall Spencer R
Published: August 2021

Why do parasites exhibit a wide dynamical range within their hosts? For instance, why can a parasite only sometimes successfully infect its host? Why do some parasites exhibit large fluctuations? Why do two parasites coinfect, exclude each other, or win only sometimes over another (via priority effects)? For insights, we turn to food webs. An omnivory model (IGP) blueprints one parasite competing with immune cells for host energy (PIE), and a competition model (keystone predation, KP) mirrors a new coinfection model (2PIE). We then draw analogies between models using feedback loops. We translate those loops into the intraspecific direct (DE) and indirect effects (IE) that create various dynamics. Three points arise. First, a prey or parasite can flip between stable and oscillatory coexistence with their enemy with weakening IE and strengthening DE. Second, even with comparable loop structure, a parasite cannot exhibit priority effects seen in IGP due to constraints imposed by production of immune cells. Third, despite simpler loop structure, KP predicts parallel outcomes in the two-parasite model due to comparable structure of interactions between competing victims and their resources and enemies. Hence, food web models offer powerful if imperfect analogies to feedbacks underlying the dynamical repertoire of parasites within hosts.
Infection and transmission of ancestral SARS-CoV-2 and its alpha variant in pregnant white-tailed deer
Authors: Cool Konner , Gaudreault Natasha N. , Morozov Igor , Trujillo Jessie D. , Meekins David A. , McDowell Chester , Carossino Mariano , Bold Dashzeveg , Kwon Taeyong , Balaraman Velmurugan , Madden Daniel W. , Artiaga Bianca Libanori , Pogranichniy Roman M. , Sosa Gleyder Roman , Henningson Jamie , Wilson William C. , Balasuriya Udeni B. R. , García-Sastre Adolfo , Richt Juergen A.
Published: August 2021

SARS-CoV-2, a novelBetacoronavirus, was first reported circulating in human populations in December 2019 and has since become a global pandemic. Recent history involving SARS-like coronavirus outbreaks (SARS-CoV and MERS-CoV) have demonstrated the significant role of intermediate and reservoir hosts in viral maintenance and transmission cycles. Evidence of SARS-CoV-2 natural infection and experimental infections of a wide variety of animal species has been demonstrated, andin silicoandin vitrostudies have indicated that deer are susceptible to SARS-CoV-2 infection. White-tailed deer (Odocoileus virginianus) are amongst the most abundant, densely populated, and geographically widespread wild ruminant species in the United States. Human interaction with white-tailed deer has resulted in the occurrence of disease in human populations in the past. Recently, white-tailed deer fawns were shown to be susceptible to SARS-CoV-2. In the present study, we investigated the susceptibility and transmission of SARS-CoV-2 in adult white-tailed deer. In addition, we examined the competition of two SARS-CoV-2 isolates, representatives of the ancestral lineage A (SARS-CoV-2/human/USA/WA1/2020) and the alpha variant of concern (VOC) B.1.1.7 (SARS-CoV-2/human/USA/CA_CDC_5574/2020), through co-infection of white-tailed deer. Next-generation sequencing was used to determine the presence and transmission of each strain in the co-infected and contact sentinel animals. Our results demonstrate that adult white-tailed deer are highly susceptible to SARS-CoV-2 infection and can transmit the virus through direct contact as well as vertically from doe to fetus. Additionally, we determined that the alpha VOC B.1.1.7 isolate of SARS-CoV-2 outcompetes the ancestral lineage A isolate in white-tailed deer, as demonstrated by the genome of the virus shed from nasal and oral cavities from principal infected and contact animals, and from virus present in tissues of principal infected deer, fetuses and contact animals.
Immune competence and spleen size scale with colony status in the naked mole-rat
Authors: Bégay Valérie , Cirovic Branko , Barker Alison J. , Klopfleisch Robert , Hart Daniel W. , Bennett Nigel C. , Lewin Gary R.
Published: August 2021

Naked mole-rats (NM-R;Heterocephalus glaber) live in multi-generational colonies with a social hierarchy, show low cancer incidence and long life-spans. Here we asked if such extreme physiology might have an immune component. The spleen is the largest lymphoid organ and plays an essential role in response to immunological insults and may participate in combating cancer and slowing ageing. We investigated the anatomy, molecular composition and function of the NM-R spleen using RNA-sequencing and histological analysis in healthy animals. We found that spleen size in healthy NM-Rs varies considerably. We therefore classified NM-Rs according to spleen size as NM-Rs with small spleens or enlarged spleens. Animals with enlarged spleens showed potentially better anti-microbial profiles and were much more likely to have a high rank within the colony. Splenomegaly was associated with infection in sick NM-Rs, but not in NM-Rs with enlarged spleens. In all healthy NM-Rs splenic erythropoiesis, megakaryopoiesis and myelopoiesis were increased, but B lymphopoiesis was reduced and splenic marginal zone showed markedly altered morphology when compared to other rodents. However, in NM-Rs lymphocytes were found in secondary sites such as lymph nodes, gut lymphoid nodules and thymus. Thus, the NM-R spleen is a major site of adult hematopoiesis under normal physiological conditions. Overall, the NM-R immune system seems to rely mainly on innate immune responses with a more restricted adaptive immune response. We propose that the anatomical plasticity of the spleen might be regulated by social interaction and gives immunological advantage to increase the life-span of higher ranked animals.
Musicians and non-musicians’ consonant/dissonant perception investigated by EEG and fMRI
Authors: Jo HanShin , Hsieh Tsung-Hao , Chien Wei-Che , Shaw Fu-Zen , Liang Sheng-Fu , Kung Chun-Chia
Published: August 2021

The perception of two (or more) simultaneous musical notes, depending on their pitch interval(s), could be broadly categorized as consonant or dissonant. Previous studies have suggested that musicians and non-musicians adopt different strategies when discerning music intervals: the frequency ratio (perfect fifth or tritone) for the former, and frequency differences (e.g., roughness vs. non-roughness) for the latter. To extend and replicate this previous finding, in this follow-up study we reran the ElectroEncephaloGraphy (EEG) experiment, and separately collected functional magnetic resonance imaging (fMRI) data of the same protocol. The behavioral results replicated our previous findings that musicians used pitch intervals and nonmusicians roughness for consonant judgments. And the ERP amplitude differences between groups in both frequency ratio and frequency differences were primarily around N1 and P2 periods along the midline channels. The fMRI results, with the joint analyses by univariate, multivariate, and connectivity approaches, further reinforce the involvement of midline and related-brain regions in consonant/dissonance judgments. Additional representational similarity analysis (or RSA), and the final spatio-temporal searchlight RSA (or ss-RSA), jointly combined the fMRI-EEG into the same representational space, providing final support on the neural substrates of neurophysiological signatures. Together, these analyses not just exemplify the importance of replication, that musicians rely more on top-down knowledge for consonance/dissonance perception; but also demonstrate the advantages of multiple analyses in constraining the findings from both EEG and fMRI.

Significance Statement

In this study, the neural correlates of consonant and dissonant perception has been revisited with both EEG and fMRI. Behavioral results of the current study well replicated the pattern of our earlier work (Kung et al., 2014), and the ERP results, though showing that both musicians and nonmusicians processed rough vs. non-rough notes similarly, still supported the top-down modulation in musicians likely through long-term practice. The fMRI results, combining univariate (GLM contrast and functional connectivity) and multivariate (MVPA searchlight and RSA on voxel-, connectivity-, and spatio-temporal RSA searchlight-level) analyses, commonly speak to lateralized and midline regions, at different time windows, as the core brain networks that underpin both musicians’ and nonmusicians’ consonant/dissonant perceptions.
Rapid fluctuations in functional connectivity of cortical networks encode spontaneous
Authors: Benisty Hadas , Barson Daniel , Moberly Andrew H. , Lohani Sweyta , Coifman Ronald R. , Mishne Gal , Crair Michael C. , Cardin Jessica A. , Higley Michael J.
Published: August 2021

Experimental work across a variety of species has demonstrated that spontaneously generated behaviors are robustly coupled to variation in neural activity within the cerebral cortex. Indeed, functional magnetic resonance imaging (fMRI) data suggest that functional connectivity in cortical networks varies across distinct behavioral states, providing for the dynamic reorganization of patterned activity. However, these studies generally lack the temporal resolution to establish links between cortical signals and the continuously varying fluctuations in spontaneous behavior typically observed in awake animals. Here, we took advantage of recent developments in wide-field, mesoscopic calcium imaging to monitor neural activity across the neocortex of awake mice. We develop a novel “graph of graphs” approach to quantify rapidly time-varying functional connectivity and show that spontaneous behaviors are represented by fast changes in both the activity and correlational structure of cortical network activity. Combining mesoscopic imaging with simultaneous cellular resolution 2-photon microscopy also demonstrated that the correlations among neighboring neurons and between local and large-scale networks also encodes behavior. Finally, the dynamic functional connectivity of mesoscale signals revealed subnetworks that are not predicted by traditional anatomical atlas-based parcellation of the cortex. These results provide new insight into how behavioral information is represented across the mammalian neocortex and demonstrate an analytical framework for investigating time-varying functional connectivity in neural networks.