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The biological roles of deubiquitinating enzymes (DUBs) in pancreatic ductal adenocarcinoma (PDAC) are not fully explored. Here the authors perform activity based proteomics with a loss of function genetic screen and identify that USP25 promotes PDAC growth and survival through HIF-1 protein stability and transcriptional activity.

Technology forecasting plays an important role in the research and development of products in any company or organization. A well-designed forecast study would help to get the maximum expected gains from future conditions while minimizing expected losses. This article focuses on forecasting of average satellite lifetimes. In this article, using data for the launch dates of satellites, we will analyze their failure (expiration) dates to better understand the curves most suitable for determining trends in satellite lifespans. This article also discusses the prediction of lifetimes of satellites currently in orbit, as well as those to be launched in the future. One goal of this paper is to explain the importance of forecasting and to give a brief explanation of forecasting methods. Another objective is to develop a best fit curve from the available past performance data of satellites by using techniques such as regression analysis, general curve fitting and valuation methods.

Numerous countries have satellites for various needs like communication, weather forecasting and security. The first satellite was launched into space in 1957. Thousands of satellites' lifetimes have already ended but many of these satellites are still in orbit although no longer functional. Nevertheless, satellite technology is improving compared with the past. We seek to understand trends in improvements to satellites related to their lifespans better, using a new dataset that has not been available before for this article, as part of a project that also analyzes other relevant data sets. The main aim of this paper is to analyze the satellite data with data visualization tools and find some significant patterns in the data. The paper explores the average lifespan of satellites over the period of artificial satellites, 1957 to present.

Abstract Triple‐negative breast cancer (TNBC) has poorer prognosis compared to other types of breast cancers due to the lack of effective therapies and markers for patient stratification. Loss of PTEN tumor suppressor gene expression is a frequent event in TNBC, resulting in over‐activation of the PI 3‐kinase (PI3K) pathway and sensitivity to its inhibition. However, PI3K pathway inhibitors show limited efficacy as monotherapies on these tumors. We report a whole‐genome screen to identify targets whose inhibition enhanced the effects of different PI3K pathway inhibitors on PTEN‐null TNBC. This identified a signaling network that relies on both the G protein‐coupled receptor for thrombin (PAR1/F2R) and downstream G protein βγ subunits and also epidermal growth factor receptor (EGFR) for the activation of the PI3K isoform p110β and AKT. Compensation mechanisms involving these two branches of the pathway could bypass PI3K blockade, but combination targeting of both EGFR and PI3Kβ suppressed ribosomal protein S6 phosphorylation and exerted anti‐tumor activity both in vitro and in vivo, suggesting a new potential therapeutic strategy for PTEN‐null TNBC.

Targeting self-renewing cancer cells without deleterious side effects in normal tissues has proven challenging. Here, the authors show that the well-tolerated HDAC inhibitor Quisinostat safely inhibits tumor maintenance and disease relapse by restoring high levels of histone H1.0.

Eukaryotic genomes express numerous long intergenic non-coding RNAs (lincRNAs) that do not overlap any coding genes. Some lincRNAs function in various aspects of gene regulation, but it is not clear in general to what extent lincRNAs contribute to the information flow from genotype to phenotype. To explore this question, we systematically analysed cellular roles of lincRNAs in Schizosaccharomyces pombe. Using seamless CRISPR/Cas9-based genome editing, we deleted 141 lincRNA genes to broadly phenotype these mutants, together with 238 diverse coding-gene mutants for functional context. We applied high-throughput colony-based assays to determine mutant growth and viability in benign conditions and in response to 145 different nutrient, drug, and stress conditions. These analyses uncovered phenotypes for 47.5% of the lincRNAs and 96% of the protein-coding genes. For 110 lincRNA mutants, we also performed high-throughput microscopy and flow cytometry assays, linking 37% of these lincRNAs with cell-size and/or cell-cycle control. With all assays combined, we detected phenotypes for 84 (59.6%) of all lincRNA deletion mutants tested. For complementary functional inference, we analysed colony growth of strains ectopically overexpressing 113 lincRNA genes under 47 different conditions. Of these overexpression strains, 102 (90.3%) showed altered growth under certain conditions. Clustering analyses provided further functional clues and relationships for some of the lincRNAs. These rich phenomics datasets associate lincRNA mutants with hundreds of phenotypes, indicating that most of the lincRNAs analysed exert cellular functions in specific environmental or physiological contexts. This study provides groundwork to further dissect the roles of these lincRNAs in the relevant conditions.

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS; the most common phenotype of corticobasal degeneration) are tauopathies with a relentless course, usually starting in the mid-60s and leading to death after an average of 7 years. There is as yet no specific or disease-modifying treatment. Clinical deficits in PSP are numerous, involve the entire neuraxis, and present as several discrete phenotypes. They center on rigidity, bradykinesia, postural instability, gait freezing, supranuclear ocular motor impairment, dysarthria, dysphagia, incontinence, sleep disorders, frontal cognitive dysfunction, and a variety of behavioral changes. CBS presents with prominent and usually asymmetric dystonia, apraxia, myoclonus, pyramidal signs, and cortical sensory loss. The symptoms and deficits of PSP and CBS are amenable to a variety of treatment strategies but most physicians, including many neurologists, are reluctant to care for patients with these conditions because of unfamiliarity with their multiplicity of interacting symptoms and deficits. CurePSP, the organization devoted to support, research, and education for PSP and CBS, created its CurePSP Centers of Care network in North America in 2017 to improve patient access to clinical expertise and develop collaborations. The directors of the 25 centers have created this consensus document outlining best practices in the management of PSP and CBS. They formed a writing committee for each of 12 sub-topics. A 4-member Steering Committee collated and edited the contributions. The result was returned to the entire cohort of authors for further comments, which were considered for incorporation by the Steering Committee. The authors hope that this publication will serve as a convenient guide for all clinicians caring for patients with PSP and CBS and that it will improve care for patients with these devastating but manageable disorders.

Background: The degree of heterotypic immunity induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains is a major determinant of the spread of emerging variants and the success of vaccination campaigns, but remains incompletely understood. Methods: We examined the immunogenicity of SARS-CoV-2 variant B.1.1.7 (Alpha) that arose in the United Kingdom and spread globally. We determined titres of spike glycoprotein-binding antibodies and authentic virus neutralising antibodies induced by B.1.1.7 infection to infer homotypic and heterotypic immunity. Results: Antibodies elicited by B.1.1.7 infection exhibited significantly reduced recognition and neutralisation of parental strains or of the South Africa variant B.1.351 (Beta) than of the infecting variant. The drop in cross-reactivity was significantly more pronounced following B.1.1.7 than parental strain infection. Conclusions: The results indicate that heterotypic immunity induced by SARS-CoV-2 variants is asymmetric. Funding: This work was supported by the Francis Crick Institute and the Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg.

Targeted CRISPR libraries expand the use of genetic screens across experimental conditions. Here, the authors develop a method for generating and analysing small scale custom CRISPR libraries and use it in the human and livestock pathogen Toxoplasma gondii to identify virulence factors in mice.

Identifying driver genes in unstable, heterogenous tumour types can be challenging. Here, Mourikis, Benedetti, Foxall and colleagues present a machine learning algorithm to tackle this problem in esophageal adenocarcinoma.

The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARS-CoV-2 detection by RT-LAMP that is robust, reliable, repeatable, specific, and inexpensive.

Recent findings suggest that forces acting on the cell nucleus can cause DNA damage, but the mechanisms are unclear. Here Takakiet al. report that actomyosin is a determinant of nuclear shape and that unrestrained contractility elicits nuclear envelope rupture and genome instability in cancer cells.

Summary: In contrast to most DNA viruses, poxviruses replicate their genomes in the cytoplasm without host involvement. We find that vaccinia virus induces cytoplasmic activation of ATR early during infection, before genome uncoating, which is unexpected because ATR plays a fundamental nuclear role in maintaining host genome integrity. ATR, RPA, INTS7, and Chk1 are recruited to cytoplasmic DNA viral factories, suggesting canonical ATR pathway activation. Consistent with this, pharmacological and RNAi-mediated inhibition of canonical ATR signaling suppresses genome replication. RPA and the sliding clamp PCNA interact with the viral polymerase E9 and are required for DNA replication. Moreover, the ATR activator TOPBP1 promotes genome replication and associates with the viral replisome component H5. Our study suggests that, in contrast to long-held beliefs, vaccinia recruits conserved components of the eukaryote DNA replication and repair machinery to amplify its genome in the host cytoplasm. : Postigo et al. suggest that, in contrast to long-held beliefs, vaccinia recruits conserved components of the eukaryote DNA replication and repair machinery to amplify its genome in the host cytoplasm. Keywords: vaccinia virus, RPA, ATR, Chk1, DNA replication, PCNA, viral replisome

For image-based infection biology, accurate unbiased quantification of host–pathogen interactions is essential, yet often performed manually or using limited enumeration employing simple image analysis algorithms based on image segmentation. Host protein recruitment to pathogens is often refractory to accurate automated assessment due to its heterogeneous nature. An intuitive intelligent image analysis program to assess host protein recruitment within general cellular pathogen defense is lacking. We present HRMAn (Host Response to Microbe Analysis), an open-source image analysis platform based on machine learning algorithms and deep learning. We show that HRMAn has the capacity to learn phenotypes from the data, without relying on researcher-based assumptions. Using Toxoplasma gondii and Salmonella enterica Typhimurium we demonstrate HRMAn’s capacity to recognize, classify and quantify pathogen killing, replication and cellular defense responses. HRMAn thus presents the only intelligent solution operating at human capacity suitable for both single image and high content image analysis.Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).

A Correction to this paper has been published: https://doi.org/10.1038/s41419-021-03530-0

Summary: In order to facilitate the identification of factors and pathways in the cellular response to UV-induced DNA damage, several descriptive proteomic screens and a functional genomics screen were performed in parallel. Numerous factors could be identified with high confidence when the screen results were superimposed and interpreted together, incorporating biological knowledge. A searchable database, bioLOGIC, which provides access to relevant information about a protein or process of interest, was established to host the results and facilitate data mining. Besides uncovering roles in the DNA damage response for numerous proteins and complexes, including Integrator, Cohesin, PHF3, ASC-1, SCAF4, SCAF8, and SCAF11, we uncovered a role for the poorly studied, melanoma-associated serine/threonine kinase 19 (STK19). Besides effectively uncovering relevant factors, the multiomic approach also provides a systems-wide overview of the diverse cellular processes connected to the transcription-related DNA damage response. : Boeing et al. investigate the UV-induced DNA damage response by combining a range of proteomic and genomic screens. A function in this response for the melanoma driver STK19 as well as a number of other factors are uncovered.

In animals, the protein kinase C (PKC) family has expanded into diversely regulated subgroups, including the Rho family-responsive PKN kinases. Here, we describe knockouts of all three mouse PKN isoforms and reveal that PKN2 loss results in lethality at embryonic day 10 (E10), with associated cardiovascular and morphogenetic defects. The cardiovascular phenotype was not recapitulated by conditional deletion of PKN2 in endothelial cells or the developing heart. In contrast, inducible systemic deletion of PKN2 after E7 provoked collapse of the embryonic mesoderm. Furthermore, mouse embryonic fibroblasts, which arise from the embryonic mesoderm, depend on PKN2 for proliferation and motility. These cellular defects are reflected in vivo as dependence on PKN2 for mesoderm proliferation and neural crest migration. We conclude that failure of the mesoderm to expand in the absence of PKN2 compromises cardiovascular integrity and development, resulting in lethality.

Summary: Signal transduction pathways stimulated by secreted growth factors are tightly regulated at multiple levels between the cell surface and the nucleus. The trafficking of cell surface receptors is emerging as a key step for regulating appropriate cellular responses, with perturbations in this process contributing to human diseases, including cancer. For receptors recognizing ligands of the transforming growth factor β (TGF-β) family, little is known about how trafficking is regulated or how this shapes signaling dynamics. Here, using whole genome small interfering RNA (siRNA) screens, we have identified the ESCRT (endosomal sorting complex required for transport) machinery as a crucial determinant of signal duration. Downregulation of ESCRT components increases the outputs of TGF-β signaling and sensitizes cells to low doses of ligand in their microenvironment. This sensitization drives an epithelial-to-mesenchymal transition (EMT) in response to low doses of ligand, and we demonstrate a link between downregulation of the ESCRT machinery and cancer survival. : Miller et al. demonstrate, using whole genome siRNA screening, that TGF-β receptors are targeted for degradation by the ESCRT machinery. Inhibiting ESCRT components upregulates long-term TGF-β signaling and enhances functional outputs of the pathway to sensitize cells to low levels of ligand in the micro-environment. Keywords: epithelial-to-mesenchymal transition, ESCRT machinery, receptor trafficking, signaling dynamics, SMAD2, TGF-β

Magnetic resonance imaging (MRI) of glioblastoma multiforme (GBM) with molecular imaging agents would allow for the specific localization of brain tumors. Prior studies using T1-weighted MR imaging demonstrated that the SBK2-Tris-(Gd-DOTA)3 molecular imaging agent labeled heterotopic xenograft models of brain tumors more intensely than non-specific contrast agents using conventional T1-weighted imaging techniques. In this study, we used a dynamic quantitative T1 mapping strategy to more objectively compare intra-tumoral retention of the SBK2-Tris-(Gd-DOTA)3 agent over time in comparison to non-targeted control agents. Our results demonstrate that the targeted SBK2-Tris-(Gd-DOTA)3 agent, a scrambled-Tris-(Gd-DOTA)3 control agent, and the non-specific clinical contrast agent Optimark™ all enhanced flank tumors of human glioma cells with similar maximal changes on T1 mapping. However, the retention of the agents differs. The non-specific agents show significant recovery within 20 min by an increase in T1 while the specific agent SBK2-Tris-(Gd-DOTA)3 is retained in the tumors and shows little recovery over 60 min. The retention effect is demonstrated by percent change in T1 values and slope calculations as well as by calculations of gadolinium concentration in tumor compared to muscle. Quantitative T1 mapping demonstrates the superior binding and retention in tumors of the SBK2-Tris-(Gd-DOTA)3 agent over time compared to the non-specific contrast agent currently in clinical use.

Amidst a crisis shortage of foster homes in the child welfare system, a number of innovative faith-based collaborations aimed at recruiting foster parents have recently emerged. It has been suggested that these collaborations offer a unique opportunity to recruit committed and altruistic parents as caregivers, providing much needed capacity to an overloaded child welfare system. This paper uses data from the National Survey of Current and Former Foster Parents to examine the associations between religious motivations for fostering, altruism and various measures of foster home utilization and longevity. The empirical results demonstrate that religiously motivated foster parents are more likely to have altruistic reasons for fostering, and scored higher than the non-religiously motivated group on an index of altruism. A separate empirical analysis shows that the interaction of high levels of altruism and religious motivation is associated with higher foster home utilization. No association was found between religious altruism and the parent’s expressed intent to continue providing foster care. The implications of these findings for current faith-based collaboration in the child welfare arena are discussed.

The expression of genes is frequently manipulated in cell lines to study their cellular functions. The use of exogenous small Interfering RNAs (siRNAs) is a very efficient technique to temporarily downregulate the expression of genes of interest [reviewed by Hannon and Rossi (2004)]. A genome-wide siRNA library allows the user to study both the effect of each individual gene on a particular cell phenotype in a high throughput manner and also assess its phenotypic effect relative to all other genes targeted. Several factors that potentially influence the outcome of a screen need to be considered when performing a large siRNA screen (Jiang et al., 2011). Here we present a detailed protocol for a genome-wide screen to identify genes involved in anti-cancer drug resistance using the human siGENOME library from Dharmacon. In this protocol, we focus on resistance to treatment with the Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor (EGFR-TKI) erlotinib in the lung cancer cell line PC9, which is exquisitely sensitive to EGFR-TKIs (de Bruin et al., 2014). This protocol can be used for other cell lines and other drug treatments, as we expand in the Notes below.

OBJECTIVE: An adverse effect of acid-suppression medications on the occurrence of Clostridium difficile infection (CDI) has been a common finding of many, but not all studies. We hypothesized that association between acid-suppression medications and CDI is due to the residual confounding in comparison between patients with infection to those without, predominantly from non-tested and less sick subjects. We aimed to evaluate the effect of acid suppression therapy on incidence of CDI by comparing patients with CDI to two control groups: not tested patients and patients suspected of having CDI, but with a negative test. METHODS: We conducted a case-control study of adult patients hospitalized in internal medicine department of tertiary teaching hospital between 2005-2010 for at least three days. Controls from each of two groups (negative for CDI and non-tested) were individually matched (1:1) to cases by primary diagnosis, Charlson comorbidity index, year of hospitalization and gender. Primary outcomes were diagnoses of International Classification of Diseases (ICD-9)-coded CDI occurring 72 hours or more after admission. RESULTS: Patients with CDI were similar to controls with a negative test, while controls without CDI testing had lower clinical severity. In multivariable analysis, treatment by acid suppression medications was associated with CDI compared to those who were not tested (OR = 1.88, p-value = 0.032). Conversely, use of acid suppression medications in those who tested negative for the infection was not associated with CDI risk as compared to the cases (OR = 0.66; p = 0.059). CONCLUSIONS: These findings suggest that the reported epidemiologic associations between use of acid suppression medications and CDI risk may be spurious. The control group choice has an important impact on the results. Clinical differences between the patients with CDI and those not tested and not suspected of having the infection may explain the different conclusions regarding the acid suppression effect on CDI risk.

Bone morphogenetic protein (BMP) gradients provide positional information to direct cell fate specification, such as patterning of the vertebrate ectoderm into neural, neural crest, and epidermal tissues, with precise borders segregating these domains. However, little is known about how BMP activity is regulated spatially and temporally during vertebrate development to contribute to embryonic patterning, and more specifically to neural crest formation. Through a large-scale in vivo functional screen in Xenopus for neural crest fate, we identified an essential regulator of BMP activity, SNW1. SNW1 is a nuclear protein known to regulate gene expression. Using antisense morpholinos to deplete SNW1 protein in both Xenopus and zebrafish embryos, we demonstrate that dorsally expressed SNW1 is required for neural crest specification, and this is independent of mesoderm formation and gastrulation morphogenetic movements. By exploiting a combination of immunostaining for phosphorylated Smad1 in Xenopus embryos and a BMP-dependent reporter transgenic zebrafish line, we show that SNW1 regulates a specific domain of BMP activity in the dorsal ectoderm at the neural plate border at post-gastrula stages. We use double in situ hybridizations and immunofluorescence to show how this domain of BMP activity is spatially positioned relative to the neural crest domain and that of SNW1 expression. Further in vivo and in vitro assays using cell culture and tissue explants allow us to conclude that SNW1 acts upstream of the BMP receptors. Finally, we show that the requirement of SNW1 for neural crest specification is through its ability to regulate BMP activity, as we demonstrate that targeted overexpression of BMP to the neural plate border is sufficient to restore neural crest formation in Xenopus SNW1 morphants. We conclude that through its ability to regulate a specific domain of BMP activity in the vertebrate embryo, SNW1 is a critical regulator of neural plate border formation and thus neural crest specification.

Epidermal growth factor receptor (EGFR) signalling is initiated by the release of EGFR-ligands from membrane-anchored precursors, a process termed ectodomain shedding. This proteolytic event, mainly executed by A Disintegrin And Metalloproteases (ADAMs), is regulated by a number of signal transduction pathways, most notably those involving protein kinase C (PKC). However, the molecular mechanisms of PKC-dependent ectodomain shedding of EGFR-ligands, including the involvement of specific PKC isoforms and possible functional redundancy, are poorly understood. To address this issue, we employed a cell-based system of PMA-induced PKC activation coupled with shedding of heparin binding (HB)-EGF. In agreement with previous studies, we demonstrated that PMA triggers a rapid ADAM17-mediated release of HB-EGF. However, PMA-treatment also results in a protease-independent loss of cell surface HB-EGF. We identified PKCα as the key participant in the activation of ADAM17 and suggest that it acts in parallel with a pathway linking PKCδ and ERK activity. While PKCα specifically regulated PMA-induced shedding, PKCδ and ERK influenced both constitutive and inducible shedding by apparently affecting the level of HB-EGF on the cell surface. Together, these findings indicate the existence of multiple modes of regulation controlling EGFR-ligand availability and subsequent EGFR signal transduction.

The use of propolis-based materials within endodontics to promote pulp wound healing or disinfect the root canal system has been a recent focus of scientists and clinicians. This is mainly because of the well-documented antimicrobial, anti-inflammatory, immunomodulatory and wound healing properties of propolis. This scoping review critically appraises the literature on the clinical applications of propolis-based compounds during endodontic therapy of primary and permanent teeth. An electronic literature search was performed in Scopus, PubMed, and Web of Science up to and including October 2023 to identify studies assessing the use of propolis during endodontic therapy of primary and permanent teeth. A combination of relevant Medical Subject Headings (MeSH) terms and keywords was used. Only human clinical studies written in English were included. The identified manuscripts were screened and assessed for inclusion by two independent authors. Eligible manuscripts were then subjected to critical appraisal and data extraction with the information being summarised according to their clinical application. A total of 26 human clinical studies were identified and included in the analysis. Propolis was investigated for use in the primary and permanent dentitions as a direct pulp capping or pulpotomy material as well as in root canal disinfection and root canal filling material of teeth with non-vital pulps. Overall, the included studies reported that the use of propolis was associated with promising outcomes in terms of efficacy to control inflammation, enhance tissue repair, and disinfection of the root canal system. However, a critical appraisal of the studies revealed a range of methodological and reporting deficiencies, resulting in unreliable results and conclusions in terms of the clinical outcomes reported. Although the studies on the use of propolis-based materials in endodontics reported promising clinical outcomes, they had a range of methodological and reporting flaws. Therefore, further well-designed and properly reported controlled clinical studies are essential to derive sound evidence-based conclusions on propolis-based materials. Furthermore, guidelines for quality assurance and safe use of propolis-based materials are necessary to enhance their production for commercial use in endodontics. [ABSTRACT FROM AUTHOR]

Aim: There are currently no high‐quality studies comparing the static navigation technique with conventional methods of fibre post removal. The aim of this ex vivo study was to compare the effectiveness of fibre post removal between a static navigation technique and a conventional freehand technique using ultrasonics by experienced and inexperienced operators. Methodology: Forty‐eight extracted single‐rooted human premolars were root‐filled. A fibre post was cemented in all 48 teeth, which were then divided randomly into the following groups: static navigation group using burs; static navigation‐ultrasonic group; and non‐guided group using ultrasonic tips. The following parameters were evaluated for both experienced operators and inexperienced operators: reaching the gutta‐percha root filling successfully, the time required to remove the entire post, the occurrence of lateral root perforations, and the amount of root dentine removed. The Kolmogorov–Smirnov test was used to examine the normality of the data; the anova test was used to compare the significant differences among groups; and Tukey tests were used for all two‐by‐two comparisons. The significance level was set at 0.05. Results: In the static navigation group, the gutta‐percha was reached significantly more frequently than in the non‐guided group (p <.05). The static navigation approach required significantly less time than the non‐guided approach to reach the gutta‐percha (p <.05). The total removal of posts was significantly different between groups (p <.05), but there was no significant difference between experienced and inexperienced operators in the static navigation group (p >.05). More perforations were associated with the non‐guided group than with the other two groups. The total mean loss of dentine in the non‐guided group in all directions was 0.39 (±0.17) mm, with 0.25 (±0.09) mm for experienced, and 0.42 (±0.16) mm for inexperienced operators. Conclusion: When compared to a conventional ultrasonic technique for the removal of fibre posts, the static navigation method using burs resulted in less dentine removal, more rapid access to the gutta‐percha root filling, less overall time to remove the posts, and fewer complications. When using static navigation, there was no difference in performance between experienced and inexperienced operators. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to evaluate and compare the validity and reliability of responses provided by GPT‐3.5, Google Bard, and Bing to frequently asked questions (FAQs) in the field of endodontics. Methodology: FAQs were formulated by expert endodontists (n = 10) and collected through GPT‐3.5 queries (n = 10), with every question posed to each chatbot three times. Responses (N = 180) were independently evaluated by two board‐certified endodontists using a modified Global Quality Score (GQS) on a 5‐point Likert scale (5: strongly agree; 4: agree; 3: neutral; 2: disagree; 1: strongly disagree). Disagreements on scoring were resolved through evidence‐based discussions. The validity of responses was analysed by categorizing scores into valid or invalid at two thresholds: The low threshold was set at score ≥4 for all three responses whilst the high threshold was set at score 5 for all three responses. Fisher's exact test was conducted to compare the validity of responses between chatbots. Cronbach's alpha was calculated to assess the reliability by assessing the consistency of repeated responses for each chatbot. Results: All three chatbots provided answers to all questions. Using the low‐threshold validity test (GPT‐3.5: 95%; Google Bard: 85%; Bing: 75%), there was no significant difference between the platforms (p >.05). When using the high‐threshold validity test, the chatbot scores were substantially lower (GPT‐3.5: 60%; Google Bard: 15%; Bing: 15%). The validity of GPT‐3.5 responses was significantly higher than Google Bard and Bing (p =.008). All three chatbots achieved an acceptable level of reliability (Cronbach's alpha >0.7). Conclusions: GPT‐3.5 provided more credible information on topics related to endodontics compared to Google Bard and Bing. [ABSTRACT FROM AUTHOR]

With the ever-increasing understanding of tooth anatomy, there is a renewed focus on the pulp chamber as an important component of the root canal system. For example, the pulp chamber is of critical relevance during diagnostic procedures such as pulp sensibility tests, deep caries removal, vital pulp treatments, access cavity preparation, tooth whitening, tooth restoration as well as methods for examining the floor of the pulp chamber to aid the detection of root canal orifices or the presence of perforations and cracks. The more recent concept of minimal invasive endodontics has also created a need to understand better the anatomy of the pulp chamber. The purpose of this article is to discuss the research methods used to study pulp chamber anatomy and the significance of the pulp chamber in endodontic research and clinical practice. In addition, directions for future research are emphasised. [ABSTRACT FROM AUTHOR]

This article proposes a new classification for pulp chamber anatomy to improve research, education, and clinical practice. Factors such as age, caries, trauma, and other conditions can influence the anatomy of pulp chambers. Understanding pulp chamber anatomy is important for various dental conditions and procedures. The article also discusses the response of pulp tissue to irritation, the impact of pulp chamber anatomy on endodontic procedures and periodontal disease, and the use of pulp chamber measurements in research methods. The document is a list of references covering various topics related to endodontics, including hereditary dentine disorders, access cavity preparation techniques, and root canal anatomy. [Extracted from the article]

A novel system to classify root and canal morphology was recently introduced (Ahmed et al. 2017). This systematic review aimed to answer the following research question: Does the Ahmed et al. system provide a more accurate and practical classification of root and canal anatomy compared to other classifications? A literature search was conducted in Google Scholar, Scopus and Wiley Online Library to identify the citation counts for the article entitled 'A new system for classifying root and root canal morphology; doi.org/10.1111/iej.12685'. After removal of duplicates and unrelated articles, 15 studies were included and analysed. All studies compared the Ahmed et al. system with the Vertucci classification. Results revealed that both systems were able to classify simple canal configurations in single‐rooted anterior and premolar teeth, disto‐buccal and palatal roots of maxillary molars. However, the Ahmed et al. system provided more accurate and comprehensive categorisations of single‐rooted teeth with complex canal anatomy, multi‐rooted maxillary and mandibular premolars and the mesio‐buccal root of maxillary molars. Further evidence on the utility of the Ahmed et al. system is required using other diagnostic devices especially in molars. [ABSTRACT FROM AUTHOR]