bluuebunny/crossref_metadata_2025 huggingface dataset:
The ribosome quality control factor Asc1 determines the fate of HSP70 mRNA on and off the ribosome
Authors: Alagar Boopathy Lokha R , Beadle Emma , Xiao Alan RuoChen , Garcia-Bueno Rico Aitana , Alecki Celia , Garcia de-Andres Irene , Edelmeier Kyla , Lazzari Luca , Amiri Mehdi , Vera Maria
Published: May 2023

Cells survive harsh environmental conditions by potently upregulating molecular chaperones such as heat shock proteins (HSPs), particularly the inducible members of the HSP70 family. The life cycle of HSP70 mRNA in the cytoplasm is unique—it is translated during stress when most cellular mRNA translation is repressed and rapidly degraded upon recovery. Contrary to its 5′ untranslated region's role in maximizing translation, we discovered that the HSP70 coding sequence (CDS) suppresses its translation via the ribosome quality control (RQC) mechanism. The CDS of the most inducible Saccharomyces cerevisiae HSP70 gene, SSA4, is uniquely enriched with low-frequency codons that promote ribosome stalling during heat stress. Stalled ribosomes are recognized by the RQC components Asc1p and Hel2p and two novel RQC components, the ribosomal proteins Rps28Ap and Rps19Bp. Surprisingly, RQC does not signal SSA4 mRNA degradation via No-Go-Decay. Instead, Asc1p destabilizes SSA4 mRNA during recovery from heat stress by a mechanism independent of ribosome binding and SSA4 codon optimality. Therefore, Asc1p operates in two pathways that converge to regulate the SSA4 mRNA life cycle during stress and recovery. Our research identifies Asc1p as a critical regulator of the stress response and RQC as the mechanism tuning HSP70 synthesis.
AT-specific DNA visualization revisits the directionality of bacteriophage λ DNA ejection
Authors: Bong Serang , Park Chung Bin , Cho Shin-Gyu , Bae Jaeyoung , Hapsari Natalia Diyah , Jin Xuelin , Heo Sujung , Lee Ji-eun , Hashiya Kaori , Bando Toshikazu , Sugiyama Hiroshi , Jung Kwang-Hwan , Sung Bong June , Jo Kyubong
Published: May 2023

In this study, we specifically visualized DNA molecules at their AT base pairs after in vitro phage ejection. Our AT-specific visualization revealed that either end of the DNA molecule could be ejected first with a nearly 50% probability. This observation challenges the generally accepted theory of Last In First Out (LIFO), which states that the end of the phage λ DNA that enters the capsid last during phage packaging is the first to be ejected, and that both ends of the DNA are unable to move within the extremely condensed phage capsid. To support our observations, we conducted computer simulations that revealed that both ends of the DNA molecule are randomized, resulting in the observed near 50% probability. Additionally, we found that the length of the ejected DNA by LIFO was consistently longer than that by First In First Out (FIFO) during in vitro phage ejection. Our simulations attributed this difference in length to the stiffness difference of the remaining DNA within the phage capsid. In conclusion, this study demonstrates that a DNA molecule within an extremely dense phage capsid exhibits a degree of mobility, allowing it to switch ends during ejection.
Realism and the Value of Explanation
Authors: Andrews Samuel John
Published: May 2023

Dasgupta poses a serious challenge to realism about natural properties. He argues that there is no acceptable explanation of why natural properties deserve the value realists assign to them and are consequently absent of value. In response, this paper defines and defends an alternative non-explanatory account of normativity compatible with realism. Unlike Lewis and Sider, who believe it is sufficient to defend realism solely on realist terms, I engage with the challenge on unfriendly grounds by revealing a tu quoque. Dasgupta and anti-realists face a similar challenge to that directed against realism: one that not only undermines the objection to realism by legitimising non-explanatory normativity but leaves them facing a significant dilemma.
An Analysis of Medical Malpractice Litigation due to Intravenous Steroid Treatment for Acute Spinal Cord Injury
Authors: Razzouk Jacob , Mehta Shaurya , Ramos Omar , Danisa Olumide , Cheng Wayne
Published: May 2023

Study Design:

Retrospective cohort study.

Objective:

To evaluate the incidence of litigation due to using or foregoing methylprednisolone (MP), naloxone, or tirilazad for treatment of acute spinal cord injury (ASCI) through querying the Westlaw and VerdictSearch databases.

Summary of Background Data:

There is historic controversy regarding the use of intravenous steroids for treatment of ASCI. Many highlight that MP continues to be used for ASCI treatment mainly as a defensive medicine tactic due to the fear of malpractice litigation.

Methods:

Westlaw and VerdictSearch were queried for cases involving steroid treatment for ASCI between the years 1998 and 2021. Collected data for each case included year of case hearing, verdict ruling, location of filed claim, and the plaintiff’s basis of litigation. Cases were reviewed and categorized by two independent reviewers based on the grievance(s) levied by the plaintiff. Inclusion criteria for topic relevance was defined as a plaintiff’s basis of litigation resting on a claim of medical malpractice due to the use, or lack thereof, of MP, naloxone, or tirilazad for treatment of ASCI.

Results:

Upon review of 238 cases, case claims were grouped into five categories based on reason for litigation: Social Security benefits (171), lawsuit due to vaccination (25), medical malpractice unrelated to steroid use (16), fungal infections due to MP injections (4), and other (22). Zero cases were found to be related to lawsuits filed due to steroid use or lack thereof for ASCI treatment.

Conclusion:

Our findings suggest there is limited risk of malpractice litigation due to steroid use or lack thereof in the treatment of ASCI. As such, steroid-related treatment decisions for ASCI should be informed by evidence-based approaches to care not influenced by medicolegal concerns.
Ninety Percent of Patients Are Satisfied With Their Decision to Undergo Spine Surgery for Degenerative Conditions
Authors: Maayan Omri , Shahi Pratyush , Merrill Robert K. , Pajak Anthony , Lu Amy Z. , Oquendo Yousi , Subramanian Tejas , Araghi Kasra , Tuma Olivia C. , Korsun Maximilian K. , Asada Tomoyuki , Singh Nishtha , Singh Sumedha , Sheha Evan D. , Dowdell James E. , Qureshi Sheeraz A. , Iyer Sravisht
Published: May 2023

Study Design.

Cross-sectional survey and retrospective review of prospectively collected data.

Objective.

To explore how patients perceive their decision to pursue spine surgery for degenerative conditions and evaluate factors correlated with decisional regret.

Summary of Background Data.

Prior research shows that one-in-five older adults regret their decision to undergo spinal deformity surgery. However, no studies have investigated decisional regret in patients with degenerative conditions.

Methods.

Patients who underwent cervical or lumbar spine surgery for degenerative conditions (decompression, fusion, or disk replacement) between April 2017 and December 2020 were included. The Ottawa Decisional Regret Questionnaire was implemented to assess prevalence of decisional regret. Questionnaire scores were used to categorize patients into low (<40) or medium/high (≥40) decisional regret cohorts. Patient-reported outcome measures (PROMs) included the Oswestry Disability Index, Patient-reported Outcomes Measurement Information System, Visual Analog Scale (VAS) Back/Leg/Arm, and Neck Disability Index at preoperative, early postoperative (<6 mo), and late postoperative (≥6 mo) timepoints. Differences in demographics, operative variables, and PROMs between low and medium/high decisional regret groups were evaluated.

Results.

A total of 295 patients were included (mean follow-up: 18.2 mo). Overall, 92% of patients agreed that having surgery was the right decision, and 90% would make the same decision again. In contrast, 6% of patients regretted the decision to undergo surgery, and 7% noted that surgery caused them harm. In-hospital complications (P=0.02) and revision fusion (P=0.026) were significantly associated with higher regret. The medium/high decisional regret group also exhibited significantly worse PROMs at long-term follow-up for all metrics except VAS-Arm, and worse achievement of minimum clinically important difference for Oswestry Disability Index (P=0.007), Patient-Reported Outcomes Measurement Information System (P<0.0001), and VAS-Leg (P<0.0001).

Conclusions.

Higher decisional regret was encountered in the setting of need for revision fusion, increased in-hospital complications, and worse PROMs. However, 90% of patients overall were satisfied with their decision to undergo spine surgery for degenerative conditions. Current tools for assessing patient improvement postoperatively may not adequately capture the psychosocial values and patient expectations implicated in decisional regret.
Trimetazidine Affects Mitochondrial Calcium Uniporter Expression to Restore Ischemic Heart Function via Reactive Oxygen Species/NFκB Pathway Inhibition
Authors: Xiao Zilong , Guan Lichun , Shi Hui , Yu Yong , Yu Ziqing , Qin Shengmei , Su Yangang , Chen Ruizhen , Li Minghui , Ge Junbo
Published: May 2023

Studies have demonstrated the roles of trimetazidine beyond being an antianginal agent in ischemic heart disease (IHD) treatment associated with mechanisms of calcium regulation. Our recent studies revealed that mitochondrial calcium uniporter (MCU, the pore-forming unit responsible for mitochondrial calcium entrance) inhibition provided cardioprotective effects for failing hearts. Because trimetazidine and MCU are associated with calcium homeostasis, we hypothesized that trimetazidine may affect MCU to restore the failing heart function. In the present study, we tested this hypothesis in the context of cardiac ischemia in vivo and in vitro. The IHD model was established in male C57BL/6 mice followed by trimetazidine administration intraperitoneally at 20 mg/kg q.o.d for 8 weeks. In vitro studies were performed in a hypoxia model using primary rat neonate cardiomyocytes. The mice survival outcomes and heart function, pathohistologic, and biological changes were analyzed. The results demonstrated that trimetazidine treatment resulted in longer life spans and heart function improvement accompanied by restoration of mitochondrial calcium levels and increase in ATP production via MCU down-regulation. Studies in vitro further showed that trimetazidine treatment and MCU inhibition decreased reactive oxygen species (ROS) production, inhibited the NFκB pathway, and protected the cardiomyocytes from hypoxic injury, and vice versa. Thus, the present study unveils a unique mechanism in which trimetazidine is involved in ameliorating the ischemic failing heart via MCU down-regulation and the following mitochondrial calcium homeostasis restoration, ROS reduction, and cardiomyocyte protection through NFκB pathway inhibition. This mechanism provides a novel explanation for the treatment effects of trimetazidine on IHD.
The effect of topical tranexamic acid on post-rhinoplasty periorbital ecchymosis and eyelid edema
Authors: Vural Omer , Inan Serhat , Buyuklu Adnan F
Published: May 2023

Background:

This study aimed to examine the effectiveness of topical tranexamic acid application in overcoming the periorbital ecchymosis and eyelid edema in patients who have undergone open technique rhinoplasty.

Methods:

Fifty patients were included in the study and divided into two groups: those who were applied topical tranexamic acid and those who were not (control). In the tranexamic acid group, tranexamic acid-soaked pledgets were placed under the skin flap in a way that both sides can reach the osteotomy area and left for 5 minutes. In the control group, isotonic saline-soaked pledgets were placed under the skin flap in the same way and left for 5 minutes. Digital photographs were obtained on postoperative day 1, 3 and 7. Eyelid edema and periorbital ecchymosis were scored by two different examiners and averaged for comparison.

Results:

The edema that developed in the patients who applied tranexamic acid was significantly less than in the control group on the postoperative day 1. There was no difference between the two groups on postoperative day 3 and 7. The ecchymosis developed in patients who applied tranexamic acid was significantly less than in the control group on all days.

Conclusions:

Topical tranexamic acid applied to the surgical field immediately after osteotomy in rhinoplasty surgery reduces the development of postoperative periorbital ecchymosis. In addition, the topical tranexamic acid application also reduces the development of eyelid edema in the early postoperative period.
Anatomical relationship between the inferior temporal septum and the temporal branch of the facial nerve for clinical applications
Authors: Lee Shin Hyo , Lee Hye-In , Kim Jeong-Nam , Shin Hyun Jin , Shin Kang-Jae
Published: May 2023

Background:

The inferior temporal septum (ITS) is a fibrous adhesion between the superficial temporal fascia and the superficial layer of the deep temporal fascia (sDTF). This study identified detailed anatomical relationship between the ITS and the temporal branch of the facial nerve (TBFN) for facial nerve preservation during temple interventions.

Methods:

Among 33 Korean cadavers, 43 sides of TBFNs in temporal regions were dissected after identifying the ITS between the superficial temporal fascia and sDTF through blunt dissection. The topography of the ITS and TBFN were investigated with reference to several facial landmarks. Regional relationships with the ITS and TBFN within the temporal fascial layers were histologically defined from five specimens.

Results:

At the level of the inferior orbital margin by the tragion, the mean distances from the lateral canthus to the anterior and posterior branches of the TBFN were 5 and 6.2 cm, respectively. At the lateral canthus level, the mean distance from the lateral canthus to the posterior branch of the TBFN was similar to that to the ITS, at 5.5 cm. At the superior orbital margin level, the posterior branch of the TBFN ran cranial to the ITS adjacent to the frontotemporal region. The TBFN ran through the sub-superficial temporal fascia layer and the nerve fibers located cranially, and within the ITS meshwork in the upper temporal compartment.

Conclusions:

The area of caution during superficial temporal fascia interventions related to the TBFN was clearly identified in the upper temporal compartment, which is known to lack important structures.

Levels of Evidence:

Basic science study
Development and evaluation of a high-fidelity rhinoplasty simulator
Authors: Podolsky Dale J , Murphy Blake D , Ahmad Jamil , Fisher David M , Wong Karen W , Drake James M , Forrest Christopher R
Published: May 2023

Rhinoplasty is a challenging procedure with a steep learning curve. Surgical simulators provide a safe platform to gain hands-on experience without compromising patient outcomes. Therefore, rhinoplasty is an ideal procedure to benefit from an effective surgical simulator. A high fidelity rhinoplasty simulator was developed using three-dimensional (3D) computer modelling, 3D printing and polymer techniques. The simulator was tested by six surgeons with experience in rhinoplasty to assess realism, anatomic accuracy, and value as a training tool. The surgeons performed common rhinoplasty techniques and were provided a Likert-type questionnaire assessing the anatomical features of the simulator. A variety of surgical techniques were successfully performed using the simulator including open and closed approaches. Bony techniques performed included endo-nasal osteotomies and rasping. Submucous resection with harvest of septal cartilage, cephalic trim, tip suturing as well as grafting techniques including alar rim, columellar strut, spreader and shield grafts were successfully performed. Overall, there was agreement in the simulator’s anatomic accuracy of bony and soft tissue features. There was strong agreement in the simulator’s overall realism and value as a training tool. The simulator provides a high-fidelity, comprehensive training platform to learn rhinoplasty techniques to augment real operating experience without compromising patient outcomes.
Acute Brain Infarction in Antineutrophil Cytoplasmic Antibody–Associated Vasculitis
Authors: Ha Jang Woo , Heo Joonnyung , Pyo Jung Yoon , Ahn Sung Soo , Song Jason Jungsik , Park Yong-Beom , Lee Sang-Won
Published: May 2023

Objectives

This study investigated the clinical and radiological features of antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV) patients with acute brain infarction, using a cohort of Korean patients with AAV.

Methods

This study included 263 patients with AAV. Acute brain infarction was defined as infarction that occurred within 7 days or less. The brain territories affected by acute brain infarction were investigated. Active AAV was arbitrarily defined as the highest tertile of Birmingham Vasculitis Activity Score (BVAS).

Results

The median age at diagnosis was 59.0 years, and 35.4% were male. Fourteen cases of acute brain infarction occurred in 12 patients (4.6%), which was calculated as 1332.2 per 100,000 patient-years and 10 times higher than the incidence rate in the Korean general population. Patients with AAV with acute brain infarction exhibited significantly older age, increased BVAS at diagnosis, and a more frequent history of prior brain infarction compared with those without. The brain territories affected in AAV patients were middle cerebral artery (50.0%), multiple territories (35.7%), and posterior cerebral artery (14.3%). Lacunar infarction and microhemorrhage were observed in 42.9% and 71.4% of cases, respectively. Prior brain infarction and BVAS at diagnosis were independently associated with acute brain infarction (hazard ratios, 7.037 and 1.089). Patients with AAV with prior brain infarction or BVAS for active AAV exhibited significantly lower cumulative acute brain infarction–free survival rates than those without.

Conclusion

Acute brain infarction was observed in 4.6% of AAV patients, and both prior brain infarction and BVAS at diagnosis were independently associated with acute brain infarction.
Colonization dynamics of a defensive insect ectosymbiont
Authors: Ganesan Ramya , Janke Rebekka S. , Kaltenpoth Martin , Flórez Laura V.
Published: May 2023

Beneficial symbionts are horizontally or vertically transmitted to offspring, relying on host- or microbe-mediated mechanisms for colonization. While multiple studies on symbionts transmitted internally or by feeding highlight host adaptations and dynamics of symbiont colonization, less is known for beneficial microbes colonizing host external surfaces, such as the insect cuticle. Here, we investigate the colonization dynamics of a bacterial symbiont that protects eggs and larvae of
Lagria villosa
beetles against pathogens. After maternal application to the egg surface, symbionts colonize specialized cuticular invaginations on the dorsal surface of larvae. We assessed the colonization time point and investigated the involvement of the host during this process. Symbionts remain on the egg surface before hatching, providing protection. Immediately after hatching, cells from the egg surface colonize the larvae and horizontal acquisition can occur, yet efficiency decreases with increasing larval age. Additionally, passive or host-aided translocation likely supports colonization of the larval symbiotic organs. This may be especially important for the dominant non-motile symbiont strain, while motility of additional strains in the symbiont community might also play a role. Our findings provide insights into the colonization dynamics of cuticle-associated defensive symbionts and suggest alternate or complementary strategies used by different strains for colonization.
Molecular Epidemiology of Antimicrobial Resistance in Central Africa: A Systematic Review
Authors: DIKOUMBA Annicet-Clotaire , ONANGA Richard , MANGOUKA Laurette G. , BOUNDENGA Larson , NGOUNGOU Edgard-Brice , GODREUIL Sylvain
Published: May 2023

Background:  In Central Africa, it is difficult to fight against antibiotic resistance, because of  a  lack of data and information on bacterial resistance, due to the low number of studies carried out in the field. To fill this gap, we carried out a systematic review of the various studies, and devise a molecular epidemiology of antimicrobial resistance from humans, animals and the environmental samples.Method:  A systematic search of all publications from 2005 to 2020 on bacterial resistance in Central Africa was performed on Pubmed, Google scholar and African journals online. All circulating resistance genes, prevalence and genetic carriers of these resistances were collected. The study area was limited to the 9 countries of Central Africa. Results:  Five hundred seventeen studies were identified through a literature search, and sixty studies carried out in 8 countries were included. Among all articles included, 43 articles were from human. Our study revealed not only the circulation of beta-lactamase and carbapenemase genes, but also several other types of resistance genes. To finish, we noticed that some studies reported mobile genetic elements such as integrons, transposons, plasmids, or chromosomes.Conclusion:  The scarcity of data poses difficulties in the implementation of effective strategies in the fight against antibiotic resistance, which requires a health policy in a "One Health" approach.
Assessment of ferroptosis-associated gene signatures as potential biomarkers for differentiating latent from active tuberculosis in children
Authors: Chen Liang , Hua Jie , Dai Xiaoting , He Xiaopu
Published: May 2023

Ferroptotic cell death is a regulated process that is governed by iron-dependent membrane lipid peroxide accumulation that plays a pathogenic role in several disease-related settings. The use of ferroptosis-related genes (FRGs) to distinguish active tuberculosis (ATB) from latent tuberculosis infection (LTBI) among children, however, remains to be analysed. Tuberculosis-related gene expression data and FRG lists were obtained, respectively, from Gene Expression Omnibus (GEO) and FerrDb. Differentially expressed FRGs (DE-FRGs) detected when comparing samples from paediatric ATB and LTBI patients were explored using appropriate bioinformatics techniques, after which enrichment analyses were performed for these genes and hub genes were identified, with these genes then being used to explore potential drug interactions and construct competing endogenous RNA (ceRNA) networks. The GSE39939 dataset yielded 124 DE-FRGs that were primarily related to responses to oxidative, chemical and extracellular stimulus-associated stress. In total, the LASSO and SVM-RFE algorithms enabled the identification of nine hub genes (MAPK14, EGLN2, IDO1, USP11, SCD, CBS, PARP8, PARP16, CDC25A) that exhibited good diagnostic utility. Functional enrichment analyses of these genes suggested that they may govern ATB transition from LTBI through the control of many pathways, including the immune response, DNA repair, transcription, RNA degradation, and glycan and energy metabolism pathways. The CIBERSORT algorithm suggested that these genes were positively correlated with inflammatory and myeloid cell activity while being negatively correlated with the activity of lymphocytes. A total of 50 candidate drugs targeting 6 hub DE-FRGs were also identified, and a ceRNA network was used to explore the complex interplay among these hub genes. The nine hub FRGs defined in this study may serve as valuable biomarkers differentiating between ATB and LTBI in young patients.
Bridging the Literacy Gap for Surgical Consents: An AI-Human Expert Collaborative Approach
Authors: Ali Rohaid , Connolly Ian D. , Tang Oliver Y. , Mirza Fatima N. , Johnston Benjamin , Abdulrazeq Hael A. , Galamaga Paul F. , Libby Tiffany J , Sodha Neel R. , Groff Michael W. , Gokaslan Ziya L. , Telfeian Albert E. , Shin John H. , Asaad Wael F. , Zou James , Doberstein Curtis E.
Published: May 2023

Abstract

Background

Despite the importance of informed consent in healthcare, the readability and specificity of consent forms often impedes patients’ comprehension. Health literacy is linked to patient outcomes, making it essential to address these issues. This study investigates the use of GPT-4 to simplify surgical consent forms and introduces an AI-human expert collaborative approach to validate content appropriateness.

Methods

Consent forms from multiple institutions were assessed for readability and simplified using GPT-4, with pre- and post-simplification readability metrics compared using nonparametric tests. Independent reviews by medical authors and a malpractice defense attorney were conducted. Finally, GPT-4’s potential for generatingde novoprocedure-specific consent forms was assessed, with forms evaluated using a validated 8-item rubric and expert subspecialty surgeon review.

Results

Analysis of 15 academic medical centers’ consent forms revealed significant reductions in average reading time, word rarity, and passive sentence frequency (allP<0.05) following GPT-4-faciliated simplification. Readability improved from an average college freshman to an 8th-grade level (P=0.004), matching the average American’s reading level. Medical and legal sufficiency consistency was confirmed. GPT-4 generated procedure-specific consent forms for five varied surgical procedures at an average 6th-grade reading level. These forms received perfect scores on a standardized consent form rubric and withstood scrutiny upon expert subspeciality surgeon review.

Conclusions

This study demonstrates the first AI-human expert collaboration to enhance surgical consent forms, significantly improving readability without sacrificing clinical detail. Our framework could be extended to other patient communication materials, emphasizing clear communication and mitigating disparities related to health literacy barriers. Ensuring AI technologies are safely incorporated into clinical practice is crucial to reach a wide range of patients, including the most vulnerable.

Data Availability Statement

The raw data was not publicly deposited due to incorporating proprietary datasets, such as the Corpus of Contemporary American English. However, data are available on request for replicability.

Code Availability Statement

The code used for these analyses are available from the authors on request.
Factors influencing practice choices of early-career family physicians in Canada: A qualitative interview study
Authors: Grudniewicz Agnes , Randall Ellen , Lavergne M. Ruth , Marshall Emily Gard , Jones Lori , Rudoler David , Horrey Kathleen , Mathews Maria , McKay Madeleine , Mitra Goldis , Scott Ian , Snadden David , Wong Sabrina T. , Goldsmith Laurie J.
Published: May 2023

Purpose

Comprehensiveness of primary care has been declining, and much of the blame has been placed on early-career family physicians and their practice choices. To better understand early-career family physicians’ practice choices in Canada, we sought to identify the factors that most influence their decisions about how to practice.

Methods

We conducted a qualitative study using framework analysis. Family physicians in their first 10 years of practice were recruited from three Canadian provinces: British Columbia, Ontario, and Nova Scotia. Interview data were coded inductively and then charted onto a matrix in which each participant’s data was summarized by code.

Results

Of the 63 participants that were interviewed, 24 worked solely in community-based practice, 7 worked solely in focused practice, and 32 worked in both settings. We identified four practice characteristics that were influenced (scope of practice, practice type and model, location of practice, and practice schedule and work volume) and three categories of influential factors (training, professional, and personal).

Conclusions

This study demonstrates the complex set of factors that influence practice choices by early-career physicians, some of which may be modifiable by policymakers (e.g., policies and regulations) while others are less so (e.g., family responsibilities). Participants described individual influences from family considerations to payment models to meeting community needs. These findings have implications for both educators and policymakers who seek to support and expand comprehensive care.

Prior presentations

“Factors influencing practice choices of early-career family physicians: A qualitative interview study.” North American Primary Care Research Group Conference (NAPCRG), Virtual, November 2021

Data also included in the following presentations on the broader study:

“Addressing the need for greater primary care coverage: A discussion on primary care practice patterns”, Evidence Café, Ontario Ministry of Health & ICES. February 14, 2023.

“The ‘kids’ are alright: Practice patterns among early-career family physicians and implication for primary care policy and workforce planning.” Family Medicine Grand Rounds, University of Ottawa. September 22, 2022.

“Practice patterns among Early-Career Primary Care (ECPC) physicians and workforce planning implications: A mixed methods study. Summary of preliminary results.” British Columbia Ministry of Health and British Columbia General Practice Services Committee. February 25, 2022.
Auranofin Inhibition of Thioredoxin Reductase Sensitizes Lung Neuroendocrine Tumor Cells (NETs) and Small Cell Lung Cancer (SCLC) Cells to Sorafenib as well as Inhibiting SCLC Xenograft Growth
Authors: Johnson Spenser S. , Liu Dijie , Ewald Jordan T. , Robles-Planells Claudia , Christensen Keegan A. , Bayanbold Khaliunaa , Wels Brian R. , Solst Shane R. , O’Dorisio M. Sue , Allen Bryan G. , Menda Yusuf , Spitz Douglas R. , Fath Melissa A.
Published: May 2023

Thioredoxin Reductase (TrxR) is a key enzyme in hydroperoxide detoxification through peroxiredoxin enzymes and in thiol-mediated redox regulation of cell signaling. Because cancer cells produce increased steady-state levels of reactive oxygen species (ROS; i.e., superoxide and hydrogen peroxide), TrxR is currently being targeted in clinical trials using the anti-rheumatic drug, auranofin (AF). AF treatment decreased TrxR activity and clonogenic survival in small cell lung cancer (SCLC) cell lines (DMS273 and DMS53) as well as the lung atypical (neuroendocrine tumor) NET cell line H727. AF treatment also significantly sensitized DMS273 and H727 cell linesin vitroto sorafenib, a multi-kinase inhibitor that was shown to decrease intracellular glutathione. The pharmacokinetic and pharmacodynamic properties of AF treatment in a mouse SCLC xenograft model was examined to maximize inhibition of TrxR activity without causing toxicity. AF was administered intraperitoneally at 2 mg/kg or 4 mg/kg (IP) once (QD) or twice daily (BID) for 1 to 5 days in mice with DMS273 xenografts. Plasma levels of AF were 10-20 μM (determined by mass spectrometry of gold) and the optimal inhibition of TrxR (50 %) was obtained at 4 mg/kg once daily, with no effect on glutathione peroxidase 1 activity. When this daily AF treatment was extended for 14 days a significant prolongation of median survival from 19 to 23 days (p=0.04, N=30 controls, 28 AF) was observed without causing changes in animal bodyweight, CBCs, bone marrow toxicity, blood urea nitrogen, or creatinine. These results show that AF is an effective inhibitor of TrxR bothin vitroandin vivoin SCLC, capable of sensitizing NETs and SCLC to sorafenib, and supports the hypothesis that AF could be used as an adjuvant therapy with agents known to induce disruptions in thiol metabolism to enhance therapeutic efficacy.
Common comorbidities in polymyalgia rheumatica and giant cell arteritis: cross-sectional study in UK Biobank
Authors: Chatzigeorgiou Charikleia , Taylor John C. , Elliott Faye , O’Sullivan Eoin P. ,   UK Biobank Eye and Vision Consortium, Morgan Ann W. , Barrett Jennifer H. , Mackie Sarah L.
Published: May 2023

Objective

To determine prevalent comorbidities in cases with polymyalgia rheumatica (PMR) or giant cell arteritis (GCA) compared to matched controls.

Methods

Nested, cross sectional case-control study within UK Biobank. Case status was defined as self-reported prior diagnosis of PMR or GCA. 10 controls per case were matched for age, sex, ethnicity and assessment centre. Associations with selected self-reported comorbidities were studied using conditional logistic regression.

Results

Of PMR (n=1036) or GCA (n=102) cases, 72% were female, 98% white and 58% reported current use of glucocorticoids. Mean age was 63. At the time of the assessment visit, compared to controls, PMR/GCA cases were more likely to report poor general health and at least several days of low mood in the two past weeks. PMR was associated with hypothyroidism (odds ratio (OR) 1.34, 95% confidence interval (CI) 1.07-1.67) and ever-use of hormone replacement therapy (OR 1.26, CI 1.07-1.47). Regarding common comorbidities, PMR and GCA were both associated with hypertension (PMR: OR 1.21, CI 1.06-1.39; GCA: OR 1.86, CI 1.23-2.81) and cataract (PMR: OR 1.51, CI 1.19-1.93; GCA: OR 3.84, CI 2.23-6.60). Additionally GCA was associated with depression (OR 3.05, CI 1.59-5.85). Neither were associated with diabetes.

Conclusion

Participants with a history of PMR/GCA, including those not currently taking glucocorticoids, rated their health as poorer than matched controls,. Some previously-described disease associations (hypothyroidism and early menopause) were replicated. Hypertension and cataract, which can both be exacerbated by long-term glucocorticoid therapy, were over-represented in both diseases, particularly GCA.

Key messages

Comorbidity was common in individuals with self-reported prior diagnosis of PMR/GCA.

PMR/GCA were associated with poorer self-reported health than controls; GCA was associated with depression.

Hypertension and cataract were over-represented in PMR/GCA compared with controls but diabetes was not.
Charting the cellular biogeography in colitis reveals fibroblast trajectories and coordinated spatial remodeling
Authors: Cadinu Paolo , Sivanathan Kisha N. , Misra Aditya , Xu Rosalind J. , Mangani Davide , Yang Evan , Rone Joseph M. , Tooley Katherine , Kye Yoon-Chul , Bod Lloyd , Geistlinger Ludwig , Lee Tyrone , Ono Noriaki , Wang Gang , Sanmarco Liliana , Quintana Francisco J. , Anderson Ana C. , Kuchroo Vijay K. , Moffitt Jeffrey R. , Nowarski Roni
Published: May 2023

Gut inflammation involves contributions from immune and non-immune cells, whose interactions are shaped by the spatial organization of the healthy gut and its remodeling during inflammation. The crosstalk between fibroblasts and immune cells is an important axis in this process, but our understanding has been challenged by incomplete cell-type definition and biogeography. To address this challenge, we used MERFISH to profile the expression of 940 genes in 1.35 million cells imaged across the onset and recovery from a mouse colitis model. We identified diverse cell populations; charted their spatial organization; and revealed their polarization or recruitment in inflammation. We found a staged progression of inflammation-associated tissue neighborhoods defined, in part, by multiple inflammation-associated fibroblasts, with unique expression profiles, spatial localization, cell-cell interactions, and healthy fibroblast origins. Similar signatures in ulcerative colitis suggest conserved human processes. Broadly, we provide a framework for understanding inflammation-induced remodeling in the gut and other tissues.
Joint Generation of Protein Sequence and Structure with RoseTTAFold Sequence Space Diffusion
Authors: Lisanza Sidney Lyayuga , Gershon Jake Merle , Tipps Sam , Arnoldt Lucas , Hendel Samuel , Sims Jeremiah Nelson , Li Xinting , Baker David
Published: May 2023

Protein denoising diffusion probabilistic models (DDPMs) show great promise in thede novogeneration of protein backbones but are limited in their inability to guide generation of proteins with sequence specific attributes and functional properties. To overcome this limitation, we develop ProteinGenerator, a sequence space diffusion model based on RoseTTAfold that simultaneously generates protein sequences and structures. Beginning from random amino acid sequences, our model generates sequence and structure pairs by iterative denoising, guided by any desired sequence and structural protein attributes. To explore the versatility of this approach, we designed proteins enriched for specific amino acids, with internal sequence repeats, with masked bioactive peptides, with state dependent structures, and with key sequence features of specific protein families. ProteinGenerator readily generates sequence-structure pairs satisfying the input conditioning (sequence and/or structural) criteria, and experimental validation showed that the designs were monomeric by size exclusion chromatography (SEC), had the desired secondary structure content by circular dichroism (CD), and were thermostable up to 95°C. By enabling the simultaneous optimization of both sequence and structure, ProteinGenerator allows for the design of functional proteins with specific sequence and structural attributes, and paves the way for protein function optimization by active learning on sequence-activity datasets.
Levamisole suppresses activation and proliferation of human T cells by the induction of a p53-dependent DNA damage response
Authors: Khan Gerarda H. , Veltkamp Floor , Scheper Mirte , Hoebe Ron A. , Claessen Nike , Butter Loes , Bouts Antonia H.M. , Florquin Sandrine , Guikema Jeroen E.J.
Published: May 2023

Levamisole (LMS) is a small molecule used in the treatment of idiopathic nephrotic syndrome (INS). The pathogenesis of INS remains unknown, but most evidence points towards an immunological basis of the disease. Recently, LMS has been shown to increase the relapse-free survival in INS patients treated in combination with corticosteroids with relatively few side effects. While LMS has been hypothesized to exert an immunomodulatory effect, its mechanism of action remains unknown. To provide insight into the working mechanism of LMS, we studied its immunomodulatory activity on in vitro activated human T cells. We show here that treatment with LMS decreased activation and proliferation of human CD4+ and CD8+ T cells. In addition, production of T cell activation-associated cytokines such as IL-2, TNF-α and IFN-γ were reduced upon LMS treatment, whereas IL-4 and IL-13 production was increased. Gene expression profiling confirmed the suppressive effects of LMS on proliferation as numerous genes involved in cell cycle progression were downregulated. Furthermore, genes associated with p53 activation and cell cycle arrest were upregulated by LMS. In agreement, LMS treatment resulted in p53 phosphorylation and increased expression of the p53 target gene FAS. Accordingly, LMS sensitized activated T cells for Fas-mediated apoptosis. Cell cycle analysis showed that LMS induced a mid-S phase arrest indicating the activation of a replication stress-associated checkpoint. In support, LMS treatment resulted in γH2AX-foci formation and phosphorylation of CHK1. Our findings indicate that LMS acts as an immunosuppressive drug that directly affects the activation and proliferation of human T cells by induction of DNA damage and the activation of a p53-dependent DNA damage response.
Phage display assisted discovery of a pH-dependent anti-α-cobratoxin antibody from a natural variable domain library
Authors: Tulika Tulika , Pedersen Rasmus W. , Rimbault Charlotte , Ahmadi Shirin , Ledsgaard Line , Bohn Markus-Frederik , Ljungars Anne , Voldborg Bjørn G. , Ruso-Julve Fulgencio , Andersen Jan Terje , Laustsen Andreas H.
Published: May 2023

Recycling antibodies can bind to their target antigen at neutral pH in the blood stream and release them upon endocytosis when pH levels drop, allowing the antibodies to be recycled into circulation via FcRn-mediated pathway, while the antigens undergo lysosomal degradation. This enables recycling antibodies to achieve the same therapeutic effect at lower doses than their non-recyclable counterparts. The development of such antibodies is typically achieved by histidine doping of the variable regions of specific antibodies or by performingin vitroantibody selection campaigns utilizing histidine doped libraries. While often successful, these strategies may introduce sequence liabilities, as they often involve mutations that may render the resultant antibodies to be non-natural. Here, we present a methodology that employs a naïve antibody phage display library, consisting of natural variable domains, to discover antibodies that bind α-cobratoxin from the venom ofNaja kaouthiain a pH-dependent manner. Upon screening of the discovered antibodies with immunoassays and bio-layer interferometry, a pH-dependent antibody was discovered that exhibits an 8-fold higher dissociation rate at pH 5.5 than 7.4. Interestingly, the variable domains of the pH-dependent antibody were found to be entirely devoid of histidines, demonstrating that pH-dependency may not always be driven by this amino acid. Further, given the high diversity available in a naïve antibody library, the methodology presented here can likely be applied to discover pH-dependent antibodies against different targetsab initiowithout the need of histidine doping.

For broader audience

Here, we present the discovery of an α-cobratoxin targeting pH-dependent antibody, with a variable region devoid of histidines, from a naïve antibody library with natural variable domains. Our findings suggest that the commonly taken approach of histidine doping to find pH-dependent antibodies may not always be required, and thus offer an alternative strategy for the discovery of pH-dependent antibodies.
Ade novolong-read genome assembly of the sacred datura plant (Datura wrightii) reveals a role of tandem gene duplications in the evolution of herbivore-defense response
Authors: Goldberg Jay K , Olcerst Aaron , McKibben Michael , Hare J Daniel , Barker Michael S , Bronstein Judith
Published: May 2023

The sacred datura plant (Solanales: Solanaceae:Datura wrightii) has been used to study plant-herbivore interactions for decades. The wealth of information that has resulted leads it to have potential as a model system for studying the ecological and evolutionary genomics of these interactions. We present ade novo Datura wrightiigenome assembled using PacBio HiFi long-reads. Our assembly is highly complete and contiguous (N50 = 179Mb, BUSCO Complete = 97.6%). We successfully detected a previously documented ancient whole genome duplication using our assembly and have classified the gene duplication history that generated its coding sequence content. We use it as the basis for a genome-guided differential expression analysis to identify the induced responses of this plant to one of its specialized herbivores (Coleoptera: Chrysomelidae:Lema daturaphila). We find over 3000 differentially expressed genes associated with herbivory and that elevated expression levels of over 200 genes last for several days. We also combined our analyses to determine the role that different gene duplication categories have played in the evolution ofDatura-herbivore interactions. We find that tandem duplications have expanded multiple functional groups of herbivore responsive genes with defensive functions, including UGT-glycosyltranserases, oxidoreductase enzymes, and peptidase inhibitors. Overall, our results expand our knowledge of herbivore-induced plant transcriptional responses and the evolutionary history of the underlying herbivore-response genes.
Attenuation of muscle spindle firing with artificially increased series compliance during stretch of relaxed muscle
Authors: Abbott Emily M , Stephens Jacob D , Simha Surabhi N , Wood Leo , Nardelli Paul , Cope Timothy C , Sawicki Gregory S , Ting Lena H
Published: May 2023

Muscle spindles relay vital mechanosensory information for movement and posture, but muscle spindle feedback is coupled to skeletal motion by a compliant tendon. Little is known about the effects of tendon compliance on muscle spindle feedback during movement, and the complex firing of muscle spindles make these effects difficult to predict. Our goal was to investigate changes in muscle spindle firing using added series elastic elements (SEEs) to mimic a more compliant tendon, and to characterize the accompanying changes in firing with respect to muscle-tendon unit (MTU) and muscle fascicle displacements (recorded via sonomicrometry). Sinusoidal, ramp-hold-release, and triangular stretches were analyzed to examine potential changes in muscle spindle instantaneous firing rates (IFRs) in locomotor-and perturbation-like stretches as well as history dependence. Added SEEs effectively reduced overall MTU stiffness and generally reduced muscle spindle firing rates, but the effect differed across stretch types. During sinusoidal stretches, peak firing rates were reduced and IFR was strongly correlated with fascicle velocity. During ramp stretches, SEEs reduced the dynamic and static responses of the spindle during lengthening but had no effect on initial bursts at the onset of stretch. Notably, IFR was negatively related to fascicle displacement during the hold phase. During triangular stretches, SEEs reduced the mean IFR during the first and second stretches, affecting the history dependence of mean IFR. Overall, these results demonstrate that tendon compliance may attenuate muscle spindle feedback during movement, but these changes cannot be fully explained by reduced muscle fascicle length and velocity.

New Findings

What is the central question of the study?

Little is known about the effects of tendon compliance on muscle spindle function. We asked whether increasing the series compliance the muscle-tendon unit muscle spindle Ia responses to stretch. We also test the relationship between muscle spindle firing rates and muscle fascicle biomechanics.

What is the main finding and its importance?

Muscle spindle firing was generally attenuated with added series compliance, with the exception of the initial burst at the onset of stretch. Overall, the changes depended upon stretch profiles, and could not be fully explained by muscle fascicle length and velocity.
Transition from Transient DNA Rereplication to Inherited Gene Amplification Following Prolonged Environmental Stress
Authors: Wright Gregory M , Menzel Johannes , Tatman Philip D. , Black Joshua C.
Published: May 2023

Cells require the ability to adapt to changing environmental conditions, however, it is unclear how these changes elicit stable permanent changes in genomes. We demonstrate that, in response to environmental metal exposure, the metallothionein (MT) locus undergoes DNA rereplication generating transient site-specific gene amplifications (TSSGs). Chronic metal exposure allows transition from MT TSSG to inherited MT gene amplification through homologous recombination within and outside of the MT locus. DNA rereplication of the MT locus is suppressed by H3K27me3 and EZH2. Long-term ablation of EZH2 activity eventually leads to integration and inheritance of MT gene amplifications without the selective pressure of metal exposure. The rereplication and inheritance of MT gene amplification is an evolutionarily conserved response to environmental metal from yeast to human. Our results describe a new paradigm for adaptation to environmental stress where targeted, transient DNA rereplication precedes stable inherited gene amplification.