Upstairs, Downstairs - conserved and divergent CLAVATA signalling in shoot meristem development and root symbioses.

BACKGROUND: The CLV3/EMBRYO-SURROUNDING REGION (CLE) peptides control plant development and response to the environment. Key conserved roles include the regulation of shoot apical meristems and the long-distance control of root colonisation by nutrient-acquiring microbes, including the widespread symbioses with arbuscular mycorrhizal fungi and nodulation with nitrogen-fixing bacteria in legumes. At least some signalling elements appear to operate across both processes but clear gaps in our understanding remain. In legumes, although CLE peptide signalling has been examined in detail in symbioses, the role of this pathway in SAM development of legumes is poorly understood. SCOPE: In this Research in Context, we review the literature to clarify the conserved and divergent elements of the CLAVATA-CLE peptide signalling pathways that control SAM, mycorrhizal colonisation and nodulation. We used novel pea mutants to determine the role of CLE signalling in regulating SAM development of a model legume, including interaction with temperature. CONCLUSIONS: We found that in pea both genetic and environmental buffering of the CLE pathway influences SAM development. In pea, the CLAVATA2 (CLV2) CLE receptor-like protein and the unknown gene product encoded by the K301 gene are required to limit SAM size and floral organ production under cool temperatures. In contrast, the CLAVATA1 receptor-like kinase promotes SAM proliferation and appears to do so via a CLV2-independent pathway. In contrast, we found no role for the RDN1 enzyme, capable of arabinosylating CLE peptides, in SAM development. Future studies in other legumes are required to examine the role of other CLE peptide signalling elements in SAM control. Studies in non-vascular mycorrhizal hosts could explore if symbioses control is also an ancestral role for this signalling pathway.

Molecular mechanisms of polarized transport to the apical plasma membrane.

Cell polarity is essential for cellular function. Directional transport within a cell is called polarized transport, and it plays an important role in cell polarity. In this review, we will introduce the molecular mechanisms of polarized transport, particularly apical transport, and its physiological importance.

Transient Apical Breakdown: Incidence, Pathogenesis, and Healing.

BACKGROUND/AIMS: Transient apical breakdown (TAB) is a phenomenon that indicates temporary apical periodontal destruction and root resorption after tooth luxation injuries, followed by the healing process of the dental pulp. Andreasen in 1986, reported that TAB was seen in approximately 4.2% of all luxation injuries. However, there have been no reports thereafter on the types and frequency of the luxation traumatic injuries in which TAB occurs. Therefore, this retrospective study was aimed to assess the incidence and pathogenesis of dental trauma-induced TAB and to suggest a possible mechanism of subsequent healing based on a series of cases. METHODS: Data analysis included mature teeth (n = 56) of 49 patients aged 9-30 years who presented in a private dental office over a period of 10 years (2012-2022) to investigate the incidence and healing sequala of TAB. RESULTS: TAB was observed in 43.8% of subluxation, 62.5% of extrusive luxation, and 75% of lateral luxation injuries. The average age of patients who developed TAB was 14.5 years, ranging from 9 to 28 years old. CONCLUSIONS: TAB can be expected in many cases of luxation injuries with minimal dislocation. Therefore, mild injuries (subluxation, extrusion, and lateral luxation), may exhibit spontaneous healing, recovery of dark discoloration of the crown, disappearance of a periapical radiolucent lesion and return to normal response to EPT as long as 12 months after the traumatic injury. Thus, a decision to perform endodontic treatment in these cases might be postponed until clear evidence for an infection exists.

Root canal cleanliness and debris extrusion following retreatment of thermoplastic injection technique and bioceramic-based root canal sealer.

OBJECTIVES: To evaluate the amount of apically extruded debris and to determine the remaining filling material on the root canal walls by microcomputed tomography (micro-CT), following the root canal retreatment of root canals filled with different obturation techniques (single cone technique, thermoplasticised injection technique) and the different root canal sealers [bioceramic-based, epoxy resin-based root canal sealer]. MATERIALS AND METHODS: 60 single rooted human premolar teeth were prepared with the ProTaper Gold system (Dentsply Maillefer) up to the F4 file and the samples were divided into 4 groups according to obturation procedures: Single cone technique + AH Plus sealer(epoxy resin-based root canal sealer, Dentsply International Inc., York, PA, USA); Single cone technique + Sure-Seal Root(bioceramic-based root canal sealer, Sure Dent Corporation, Gyeonggi-do, South Korea); thermoplastic injection technique[Calamus Dual Obturation System(Dentsply-Tulsa Dental, Tulsa, OK, USA)] + AH Plus(Dentsply International Inc.); Sure-Seal Root(Sure Dent Corporation) + Calamus Dual Obturation System (Dentsply-Tulsa Dental). The teeth were inserted into preweighed Eppendorf tubes and retreatment was performed. The tubes were kept in an incubator at 37 °C for 14 days to obtain the dry debris weight. Following the removal of the root canal fillings, the samples were scanned with a micro-CT device to analyse the volume of filling residues. RESULTS: Retreatment of samples obturated with epoxy-resin or bioceramic based root sealers combined with Calamus system resulted in higher amount of apical extrusion compared to their combination with single cone technique (p = 0.026 for Single cone technique + AH Plus sealer vs Calamus + AH Plus sealer and p = 0.005 for Single cone technique + Sure-Seal root sealer vs Calamus + Sure-Seal root sealer). The most debris was observed in the Calamus + Sure-Seal root sealer group, the least debris was observed in the Single cone technique + AH Plus sealer group. The percentage of residues was the highest in the Single cone technique + Sure-Seal root sealer and the lowest in the Calamus + AH Plus sealer group, but there were no significant differences between groups (p = 0.463). CONCLUSIONS: No correlation was observed among the groups in terms of extruded debris and remnants inside the root canal. When combined with bioceramic based sealer, thermoplasticised injection technique did not affect the cleanliness of root canal walls; however, it increased its apical extrusion potential during retreatment. CLINICAL RELEVANCE: The obturation method does not play a role in the removability of bioceramic based root canal sealer, however the use of bioceramic-based root canal sealers with cold obturation techniques may be beneficial in preventing apical extrusion.

Efficacy of Glycyrrhizin as an Intracanal Medicament on Bacterial Load Reduction in Primary Infected Root Canals: A Randomized Clinical Trial.

AIM: This study was done to clinically investigate the efficacy of glycyrrhizin-based intracanal medication (ICM) compared to calcium hydroxide Ca(OH)2 and Ledermix on the bacterial counts inside the root canals of necrotic teeth with chronic periapical periodontitis. METHODOLOGY: Thirty-six patients having single-rooted and single-canaled necrotic teeth with chronic periapical periodontitis were enrolled in this research. Aseptic control measures were taken before clinical steps. Access cavity preparation was done. First bacteriological samples (S1) were collected immediately after access cavity preparation and before cleaning and shaping inside the root canals. Cleaning and shaping were performed on the root canals. Patients were randomly allocated into 3 groups according to the type of intracanal medicament used [Ca(OH)2, Ledermix, Glycyrrhizin]. Second bacteriological samples (S2) were collected after 1 week from placing the ICMs. S1 and S2 were transferred to the lab of microbiology for culturing on blood agar dishes in anaerobic conditions, and the bacteria on the plates were enumerated as colony-forming units (CFUs) by the manual counting method. The anti-bacterial efficacy of the ICM was estimated by the percentage reduction in the bacterial colonies from S1 to S2. RESULTS: All tested ICM documented a significant reduction in the CFUs from S1 to S2 (p < 0.05). Regarding S1, there was no significant difference between the three tested materials (p > 0.05). Regarding S2, Glycyrrhizin and Ledermix showed significantly lower CFUs than Ca(OH)2. There was no significant difference between Glycyrrhizin and Ledermix. CONCLUSION: Under the conditions of the present study, Glycyrrhizin and Ledermix showed comparable antimicrobial effects that were better than the commonly used Ca(OH)2 ICM. Glycyrrhizin may be a promising ICM. CLINICAL SIGNIFICANCE: Herbal medicine can be considered as an alternative antimicrobial material for root canal disinfection because it has many benefits, like low toxicity, absence of microbial resistance, and favorable antimicrobial efficacy. This study highlights the clinical efficacy of Glycyrrhizin as a promising ICM. How to cite this article: Eltantawi AR, Abdel-Razik GM, Elhawary YM, et al. Efficacy of Glycyrrhizin as an Intracanal Medicament on Bacterial Load Reduction in Primary Infected Root Canals: A Randomized Clinical Trial. J Contemp Dent Pract 2024;25(6):540-546.

Associations Between Short-Term Postoperative Outcomes and Immunocompromised Status in Patients Undergoing Sacrocolpopexy.

INTRODUCTION AND HYPOTHESIS: Few data exist on the impact of immunosuppression on perioperative outcomes in women undergoing sacrocolpopexy. The objective of this study was to compare differences in 30-day perioperative morbidity in immunocompromised versus non-immunocompromised women undergoing sacrocolpopexy (SCP). We hypothesize that compared with the non-immunocompromised group, immunocompromised women undergoing SCP experience worse composite 30-day postoperative outcomes. METHODS: Retrospective cohort of female patients aged 18 years or older who underwent sacrocolpopexy from 2012 to 2017. Current procedural terminology (CPT) codes 57280 and 57425 identified sacrocolpopexy in the American College of Surgeons-National Surgical Quality Improvement Project database. The primary exposure was a binary indicator of immunocompromised status, and the primary outcome was a composite indicator of readmission, reoperation, or a severe adverse event 30 days after surgery. Marginal standardization, a G-computation method, was used to estimate risk ratios (RR) and 95% confidence intervals (CI) representing the association between exposure and outcome. RESULTS: A total of 13,505 women underwent SCP between 2012 and 2017. Of those, 2,625 (19.4%) had an indicator of immunocompromised status, with diabetes and smoking being most common. The risk of the composite adverse outcome in immunocompromised women was 7.3% versus 4.6% in non-immunocompromised women. After adjusting for age, race, ethnicity, and body mass index, immunocompromised women experienced 54% increased relative risk of an adverse outcome, compared with non-immunocompromised women (RR = 1.54; 95% CI: 1.31, 1.82). CONCLUSIONS: Immunocompromised status, most commonly caused by diabetes and smoking, increases the risk of readmission, reoperation, and a severe adverse event within 30 days of sacrocolpopexy.

Microbial diversity in primary endodontic infections: demographics and radiographic characteristics.

OBJECTIVE: To analyze if the microbiome community composition in primary endodontic infections is associated with clinical or radiographic factors. MATERIALS AND METHODS: Seventy-one patients with primary endodontic infections were evaluated for percussion tenderness, presence of a sinus tract, presence of caries, sex, probing depth > 4 mm, and age. Samples from the root canals were obtained and the microbiome was subsequently characterized by 16 S rRNA amplicon sequencing. For the radiographic analysis, a subset of 12 samples with a periapical index (PAI) ≤ 2 were compared with 19 samples with PAI of 5. The Shannon and Chao1 indices were used to measure alpha diversity. Differences in abundances of genera were evaluated using the Kruskal-Wallis test with Bonferroni's correction. Differences in community composition were evaluated using analysis of similarity (ANOSIM) with Bray-Curtis dissimilarity matrices. RESULTS: No significant differences in microbiome composition relative to clinical factors were found using ANOSIM. Teeth within the two categories of periapical index showed a similar number of species richness, and alpha diversity values P > 0.05. Community composition was significantly affected by the periapical index (ANOSIM P = 0.039, R = 0.10). Larger radiographic lesions demonstrated significant increase in Prevotellaceae, Olsenella, and the motile bacteria Oribacterium, Selenomonadaceae spp., and Treponema. CONCLUSION: Clinical factors associated with apical periodontitis have a limited impact on the root canal microbiome composition. Community composition appears to be affected in teeth with large apical lesions.

Chronological events unfolding the vegetative and floral phenology of apical bud in Crocus sativus.

Saffron (Crocus sativus L.) is an infertile perennial geophyte considered the most expensive spice in the world. Seasonal fluctuations and climate change have significant impact on the growth, development, and yield of saffron stigma, which is the economically valued part of plant. The stigma being part of the flower, the knowledge of phenotypic transition from dormant apical bud up to flowering is vital, yet, not explored properly. The complexity of flowering in C. sativus further accentuates by the lack of clear demarcation between flowering and non-flowering corms in terms of weight and sizes, as small corms are known to be vegetative only, while large ones produce flower. Therefore, chronological phenotyping on a weekly and quarterly basis of apical shoot and flowering primordia between June and October was carried out to understand the organogenesis sequentially. In large corms, the stamen was the first floral organ to initiate followed by the formation of tepal from the base of the stamen. The plants exhibited both synanthous and hysteranthous flowering. Untargeted metabolome analysis of dormant apical bud just before dormancy break from flowering buds from large corms as well as non-flowering buds from small corms identified the presence of many differentially accumulated metabolites including sphingosine and meglutol. Key metabolites such as phytosphingosine, 3-hydroxy-3-methyl glutaric acid, 3-acetamidopropanal, 6-hydroxykynurenic acid, D-serine, and 1-D-myo-inositol 3-phosphate were also detected having associated with isoprenoid biosynthesis, lignin pathway regulation, and carbohydrate metabolism that participates in flowering. The integration of morphological, histological, and metabolomic data offers a comprehensive view of the flowering process that can be utilised in future biotechnological interventions in C. sativus.

Adaptations and metabolic evolution of myzozoan protists across diverse lifestyles and environments.

SUMMARYMyzozoans encompass apicomplexans and dinoflagellates that manifest diverse lifestyles in highly varied environments. They show enormous propensity to employ different metabolic programs and exploit different nutrient resources and niches, and yet, they share much core biology that underlies this evolutionary success and impact. This review discusses apicomplexan parasites of medical significance and the traits and properties they share with non-pathogenic myzozoans. These include the versatility of myzozoan plastids, which scale from fully photosynthetic organelles to the site of very select key metabolic pathways. Pivotal evolutionary innovations, such as the apical complex, have allowed myzozoans to shift from predatory to parasitic and other symbiotic lifestyles multiple times in both apicomplexan and dinoflagellate branches of the myzozoan evolutionary tree. Such traits, along with shared mechanisms for nutrient acquisition, appear to underpin the prosperity of myzozoans in their varied habitats. Understanding the mechanisms of these shared traits has the potential to spawn new strategic interventions against medically and veterinary relevant parasites within this grouping.

In Vitro Efficacy of Apical Negative Pressure Irrigation in Primary Teeth: A Smear Layer Analysis.

Aim and background: This study aimed to assess the efficacy of root canal debris removal in primary teeth through irrigation using the Endo-Irrigator Plus (CWAIS). Materials and methods: A total of 25 primary mandibular first molars were divided into five groups, with five teeth in each group. After determining the working length and performing biomechanical preparation, groups I and II were subjected to hand and rotary instrumentation (ProTaper, Dentsply, United States of America) with conventional syringe irrigation with positive pressure, while groups III and IV were instrumented using hand and rotary instrumentation with positive and negative pressure irrigation employing the Endo-Irrigator Plus (CWAIS) system. Sodium hypochlorite (5.25%) and ethylenediaminetetraacetic acid (EDTA) (17%) were used as irrigants. Group V served as the control group, undergoing only root canal access opening. The removal of the smear layer was analyzed at the cervical, middle, and apical thirds of the canal using environmental scanning electron microscopy (SEM). Statistical significance was set at p < 0.05. Results: Statistically significant differences were observed among all groups at the cervical, middle, and apical levels (p < 0.05). Groups III and IV exhibited significantly lower smear scores at all levels, particularly in the apical third, as observed through SEM examination. Conclusion: The use of the Endo-Irrigator Plus (CWAIS) system demonstrated superior debridement of intracanal debris in primary teeth compared to the positive pressure irrigation method. How to cite this article: Badnaware SD, Kakade A, Takate V, et al. In Vitro Efficacy of Apical Negative Pressure Irrigation in Primary Teeth: A Smear Layer Analysis. Int J Clin Pediatr Dent 2024;17(6):653-657.

A Practical Approach to the Diagnosis and Initial Management of Acute Right Ventricular Failure during Pregnancy using Point-of-Care Ultrasound.

Acute right ventricular failure is a critical condition in pregnancy that can lead to severe maternal and fetal complications. This expert review discusses the instrumental role of Point-of-Care Ultrasound in diagnosing and managing ARVF in pregnant patients, highlighting its benefits for immediate clinical decision-making in obstetric emergencies. The unique physiological changes during pregnancy, such as increased blood volume and cardiac output, can exacerbate underlying or latent cardiac issues, making pregnant patients particularly susceptible to acute right ventricular failure. Common causes during pregnancy include pulmonary embolism, peripartum cardiomyopathy, and congenital heart diseases, each presenting distinct challenges in diagnosis and management. The real-time capability of point-of-care ultrasound allows for the immediate assessment of right ventricular size and function, evaluation of fluid status via the inferior vena cava, and identification of potential pulmonary embolism, offering a non-invasive, rapid, and dynamic diagnostic tool right at the bedside. The expert review details specific point-of-care ultrasound techniques adapted for pregnant patients, including the parasternal long and short axis and apical four-chamber view, essential for evaluating right heart function and guiding acute management strategies. These include fluid management, adjustment of pharmacological treatment, and immediate interventions to support cardiac function and reduce ventricular overload. Point-of-care ultrasound enhances clinical outcomes by allowing clinicians to make informed decisions quickly, reducing the time to intervention, and tailoring management strategies to individual patient needs. However, despite its apparent advantages, the adoption of point-of-care ultrasound requires specialized training and familiarity with obstetric-specific protocols. This review advocates for the integration of point-of-care ultrasound into standard obstetric care protocols, emphasizing the need for clear guidelines and structured protocols that equip healthcare providers with the skills necessary to utilize this technology effectively. Future research should aim to refine these protocols and expand the evidence base to solidify the role of point-of-care ultrasound in improving maternal and fetal outcomes in acute right ventricular failure.

Natural selection on apical membrane antigen 1 (AMA1) of an emerging zoonotic malaria parasite Plasmodium inui.

Apical membrane antigen 1 (AMA1) of malaria parasites plays an important role in host cell invasion. Antibodies to AMA1 can inhibit malaria merozoite invasion of erythrocytes while vaccine-induced specific cytotoxic T cell responses to this protein are associated with clinical protection. Polymorphisms in AMA1 of Plasmodium falciparum (PfAMA1) and P. vivax (PvAMA1) are of concern for vaccine development. To date, little is known about sequence diversity in ama1 of P. inui (Piama1), an emerging zoonotic malaria parasite. In this study, 80 complete Piama1 coding sequences were obtained from 57 macaques in Thailand that defined 60 haplotypes clustering in two phylogenetic lineages. In total, 74 nucleotide substitutions were identified and distributed unevenly across the gene. Blockwise analysis of the rates of synonymous (dS) and nonsynonymous (dN) nucleotide substitutions did not show a significant deviation from neutrality among Thai isolates. However, significantly negative Tajima's D values were detected in domain I and the loop region of domain II, implying purifying selection. Codon-based analysis of dN/dS has identified 12 and 14 codons under positive and negative selections, respectively. Meanwhile, 85 amino acid substitutions were identified among 80 Thai and 11 non-Thai PiAMA1 sequences. Of these, 48 substituted residues had a significant alteration in physicochemical properties, suggesting positive selection. More than half of these positively selected amino acids (32 of 48) corresponded to the predicted B-cell or T-cell epitopes, suggesting that selective pressure could be mediated by host immunity. Importantly, 14 amino acid substitutions were singletons and predicted to be deleterious that could be subject to ongoing purifying selection or elimination. Besides genetic drift and natural selection, intragenic recombination identified in domain II could generate sequence variation in Piama1. It is likely that malarial ama1 exhibits interspecies differences in evolutionary histories. Knowledge of the sequence diversity of the Piama1 locus further provides an evolutionary perspective of this important malaria vaccine candidate.

An Unlikely Cause of Chest Pain: Recurrent Takotsubo Cardiomyopathy.

Takotsubo cardiomyopathy is described as transient, ventricular dysfunction. A relatively rare pathology accounting for 0.02% of hospitalizations, recurrent episodes are even less common, occurring at 1-6%. Here, we present a case of an elderly woman presenting with multiple, recurrent episodes of takotsubo cardiomyopathy. Similarities and differences between our case and others presented in literature are compared. Our case highlights the importance of maintaining a broad differential when presented with multiple episodes of recurrent, acute heart failure in the setting of chest pain and ST segment elevations.

OsMAPKKKε regulates apical spikelet development by adjusting Reactive Oxygen Species accumulates in Oryza sativa.

Rice panicle abortion can significantly impact rice yield and food security. Recent research has revealed that panicle abortion is influenced by environmental factors as well as regulated by specific genes. Here we report a novel panicle apical abortion 4 (paa4) mutant with semi-dwarf and panicle apical abortion phenotype, and its abortion occurs when the panicle length is approximately 7 cm. Map-based cloning has identified that PAA4 encodes a Mitogen-activated Protein Kinase Kinase Kinase ε (OsMAPKKKε) protein, and a substitution of G to A in exon 19 of OsMAPKKKε that leads to panicle apical abortion. PAA4 has a higher expression in the spikelet although which expressed in all organs of rice. During panicle growth, excessive Reactive Oxygen Species (ROS) accumulate in the apical panicle of paa4, eventually inducing programmed cell death (PCD). Transcriptome sequencing indicates that PAA4 plays a role in both the generation and elimination of ROS. Therefore, PAA4 might be involved in the balance of ROS at the apical panicle and then affects spikelet development in Oryza sativa.

Comparing Echocardiographic Strain Imaging in Cardiac Amyloid and End-Stage Renal Disease Patients.

PURPOSE: Diagnosing cardiac amyloidosis (CA) is difficult due to nonspecific clinical symptoms and echocardiographic findings. Prior studies have suggested that apical sparing strain patterns may be diagnostically useful. With increasing strain usage, it remains unclear how specific this pattern is to diagnose CA. We analyzed strain patterns between CA and end-stage renal disease (ESRD) patient populations. METHODS: Patients with ESRD proven negative for CA (n = 19) were compared to CA patients with CKD stage 3 or less (n = 25). The ESRD cohort was stratified based on time on dialysis. Echocardiographic longitudinal strain (LS) parameters were collected, including regional and global LS, echocardiographic, and demographic parameters. Relative apical LS was calculated using the following equation: average apical LS/(average mid LS + average basal LS). RESULTS: No significant differences were found regarding regional strain or relative apical strain. Our study showed a sensitivity of 80% and specificity of 42% when using a relative apical strain ratio of >1. All groups demonstrated an apical sparing strain pattern visually on the bulls-eye plot. CONCLUSION: ESRD demonstrates significant overlapping findings across various imaging modalities compared to CA. We demonstrated that relative apical sparing strain is nonspecific for CA among patients with ESRD. Our study calls into question the clinical value of relative apical-sparing stain patterns in identifying CA in an ESRD population and suggests that diagnostic evaluation should be driven by strong clinical suspicion and other imaging and demographic variables.

Sacrocolpopexy: The Way I Do It.

INTRODUCTION AND HYPOTHESIS: Sacrocolpopexy (SCP) is an established surgical procedure for apical vaginal vault prolapse. There remains significant variation amongst surgeons in both the surgical steps and concomitant surgeries utilised when undertaking an SCP. METHODS: This review article is aimed at summarising the evidence and providing a detailed update of SCP in modern practice, reviewing contemporary evidence behind its indications, efficacy, outcomes, surgical steps, and complications. RESULTS: Sacrocolpopexy remains the gold standard for post-hysterectomy apical prolapse based on good long-term outcomes, patient satisfaction and low complication rates. SCP with concomitant total hysterectomy is not recommended owing to high rates of mesh exposure. The laparoscopic approach remains the preferred option in terms of low morbidity, quicker recovery and lower cost than alternative access options. For optimal outcomes an SCP should be performed with monofilament mesh, using absorbable sutures and with a paravaginal repair for cystocele. CONCLUSIONS: Although SCP has become increasingly utilised for apical prolapse, its established efficacy regarding anatomical outcomes, patient satisfaction, and complications is in the context of post-hysterectomy prolapse. SCP with concomitant total hysterectomy has higher rates of mesh exposure. The efficacy and safety of SCP with sub-total hysterectomy or hysteropexy have not been clearly established and require further assessment through well-designed, rigorous randomised controlled trials.

Actin-mediated avoidance of tricellular junction influences global topology at the Arabidopsis shoot apical meristem.

Division plane orientation contributes to cell shape and topological organization, playing a key role in morphogenesis, but the precise physical and molecular mechanism influencing these processes remains largely obscure in plants. In particular, it is less clear how the placement of the new walls occurs in relation to the walls of neighboring cells. Here, we show that genetic perturbation of the actin cytoskeleton results in more rectangular cell shapes and higher incidences of four-way junctions, perturbing the global topology of cells in the shoot apical meristem of Arabidopsis thaliana. Actin mutants also exhibit changes in the expansion rate of the new versus the maternal cell wall after division, affecting the evolution of internal angles at tricellular junctions. Further, the increased width of the preprophase band in the actin mutant contributes to inaccuracy in the placement of the new cell wall. Computational simulation further substantiates this hypothesis and reproduces the observed cell shape defects.

Machine learning and deep learning models for the diagnosis of apical periodontitis: a scoping review.

OBJECTIVES: To assess the existing literature on the use of machine learning (ML) and deep learning (DL) models for diagnosing apical periodontitis (AP) in humans. MATERIALS AND METHODS: A scoping review was conducted following the Arksey and O'Malley framework. The PubMed, SCOPUS, and Web of Science databases were searched, focusing on articles using ML/DL approaches for AP diagnosis. No restrictions were applied. Two independent reviewers screened publications and charted data in predefined Excel tables for analysis. RESULTS: Nineteen publications focused on diagnosing AP by identifying periapical radiolucent lesions (PRLs) in dental radiographs were included. The average sensitivity and specificity for reviewed models were 83% and 90%, respectively. Only three studies explored the direct impact of artificial intelligence (AI) assistance on clinicians' diagnostic performance. Both consistently showed improved sensitivity without compromising specificity. Significant variability in dataset sizes, labeling techniques, and algorithm configurations was noticed. CONCLUSIONS: Findings affirm AI models' effectiveness and transformative potential in diagnosing AP by improving the accurate detection of periapical radiolucencies using dental radiographs. However, the lack of standardized reporting on crucial aspects of methodology and performance metrics prevents establishing a definitive diagnostic approach using AI. Further studies are needed to expand AI applications in AP diagnosis beyond radiographic analysis. CLINICAL RELEVANCE: AI can potentially improve diagnostic accuracy in AP diagnosis by enhancing the sensitivity of PRL detection in dental radiographs without compromising specificity.

[Repair of perirradicular tissues in non-surgical endodontic treatment. A review]. / Reparación de tejidos perirradiculares en el tratamiento endodóntico no quirúrgico. Una revisión.

Introduction: Non-surgical endodontic treatment aims to prevent apical periodontitis, achieved with the disinfection of the root canal system. Additionally, there are pathologies where the toxic content of the canal goes to the periradicular tissues, causing osteolysis or lesions of the bone tissue that are radiographically observed as radiolucent images. When the endodontic treatment is successful, the repair of these lesions occurs over time. Aim: To analyze the periradicular repair process of non-surgical endodontic treatment and the factors that affect it. Materials and Methods: An electronic search was carried out using the search engines PUBMED, Scopus, Google Academic, and Scielo with the words "Non-Surgical Endodontic Treatment," "Periapical Tissues," "Biological Repair," "Apical Repair." Factors such as incomplete texts, PDF texts, and publication date of the article were considered, including data from the last five (05) years. Results: The information reviewed comprised 236 articles analyzed with the inclusion and exclusion criteria, and only 42 articles met these criteria. Conclusion: The success of endodontic treatment lies in the absence of clinical and radiographic signs and symptoms of infection; this is achieved with a good application of clinical protocols and procedures focused on the disinfection of the root canal system, from diagnosis, biomechanical preparation, and disinfection of the root canal system with irrigating substances and filling, including coronal rehabilitation from an aesthetic and/or prosthetic point of view.

Cellular psychology: relating cognition to context-sensitive pyramidal cells.

'Cellular psychology' is a new field of inquiry that studies dendritic mechanisms for adapting mental events to the current context, thus increasing their coherence, flexibility, effectiveness, and comprehensibility. Apical dendrites of neocortical pyramidal cells have a crucial role in cognition - those dendrites receive input from diverse sources, including feedback, and can amplify the cell's feedforward transmission if relevant in that context. Specialized subsets of inhibitory interneurons regulate this cooperative context-sensitive processing by increasing or decreasing amplification. Apical input has different effects on cellular output depending on whether we are awake, deeply asleep, or dreaming. Furthermore, wakeful thought and imagery may depend on apical input. High-resolution neuroimaging in humans supports and complements evidence on these cellular mechanisms from other mammals.