Apical Tissue Research Articles

Morphological, Physiological, and Transcriptional Changes in Crocus sativus L. Under In Vitro Polyethylene Glycol-Induced Water Stress.

Saffron (Crocus sativus L.), a perennial geophyte from the Iridaceae family, blooms in autumn and thrives in Mediterranean-like climates. It is highly valued for its therapeutic and commercial uses. While saffron cultivation generally requires minimal water, insufficient irrigation can negatively impact its yield. Although numerous studies have explored the detrimental impact of drought on saffron under field conditions, its impact in vitro remains largely unexplored. The present study aims to investigate the effects of polyethylene glycol (PEG) 6000 at concentrations of 0%, 5%, and 10% in inducing drought stress on saffron shoots under controlled conditions. The research focuses on evaluating morphological, physiological, and biochemical changes and analyzing the expression of drought-responsive genes. Shoot establishment was carried out on Murashige and Skoog (MS) medium supplemented with 6 mg/L 6-benzyladenine (BAP) and 1 mg/L naphthaleneacetic acid (NAA), while PEG 6000 was used to induce drought stress. Various morphological, biochemical, and molecular parameters were assessed 30 days after stress induction. Increasing PEG concentrations in the medium significantly reduced shoot regeneration, leading to increased apical tissue browning. Significant chlorophyll and carotenoid level changes were observed in shoots exposed to higher PEG concentrations. PEG-induced drought led to decreased plant growth and biomass and lowered relative water content of leaves. Lipid peroxidation, membrane damage, and H2O2 content increased, indicating heightened stress levels. Proline concentration significantly increased in plants subjected to 5% and 10% PEG compared to controls. Non-enzymatic antioxidant activity (phenolics, flavonoids, % inhibition, total reducing power, and total antioxidant activity) also increased with the severity of stress. In contrast, a decrease in the activity of superoxide dismutase (SOD) and peroxidase was observed in PEG-treated shoots. Significant changes in the expression of drought-related genes, such as DREB1, DREB2, AREB1, DHN1 (Dehydrin), and SnRK2, were observed in shoots exposed to 5% and 10% PEG. In conclusion, the study highlights that PEG, as an inducer of drought stress, negatively impacts saffron's growth and physiological responses under in vitro conditions. It also triggers significant changes in biochemical and molecular mechanisms, indicating the plant's susceptibility to water scarcity.

Algorithm for Locating Apical Meristematic Tissue of Weeds Based on YOLO Instance Segmentation

Laser technology can be used to control weeds by irradiating the apical meristematic tissue (AMT) of weeds when they are still seedlings. Two factors are necessary for the successful large-scale implementation of this technique: the ability to accurately identify the apical meristematic tissue and the effectiveness of the localization algorithm used in the process. Based on this, this study proposes a lightweight weed AMT localization algorithm based on YOLO (look only once) instance segmentation. The YOLOv8n-seg network undergoes a lightweight design enhancement by integrating the FasterNet lightweight network as its backbone, resulting in the F-YOLOv8n-seg model. This modification effectively reduces the number of parameters and computational demands during the convolution process, thereby achieving a more efficient model. Subsequently, F-YOLOv8n-seg is combined with the connected domain analysis algorithm (CDA), yielding the F-YOLOv8n-seg-CDA model. This integration enables the precise localization of the AMT of weeds by calculating the center-of-mass coordinates of the connected domains. The experimental results indicate that the optimized model significantly outperforms the original model; the optimized model reduces floating-point computations by 26.7% and the model size by 38.2%. In particular, the floating-point calculation is decreased to 8.9 GFLOPs, and the model size is lowered to 4.2 MB. Comparing this improved model against YOLOv5s-seg and YOLOv10n-seg, it is lighter. Furthermore, it exhibits exceptional segmentation accuracy, with a 97.2% accuracy rate. Experimental tests conducted on five different weed species demonstrated that F-YOLOv8n-seg-CDA exhibits strong generalization capabilities. The combined accuracy of the algorithm for detecting these weeds was 81%. Notably, dicotyledonous weeds were detected with up to 94%. Additionally, the algorithm achieved an average inference speed of 82.9 frames per second. These results indicate that the algorithm is suitable for the real-time detection of apical meristematic tissues across multiple weed species. Furthermore, the experimental results demonstrated the impact of distinctive variations in weed morphology on identifying the location of the AMT of weeds. It was discovered that dicotyledonous and monocotyledonous weeds differed significantly in terms of the detection effect, with dicotyledonous weeds having significantly higher detection accuracy than monocotyledonous weeds. This discovery can offer novel insights and avenues for future investigation into the identification and location of the AMT of weeds.

Characterization of Caulimovirid-like Sequences from Upland Cotton (Gossypium hirsutum L.) Exhibiting Terminal Abortion in Georgia, USA.

In this study, we investigated the potential involvement of endogenous viral elements (EVEs) in the development of apical tissue necrosis, resulting in the terminal abortion of upland cotton (Gossypium hirsutum L.) in Georgia. The high-throughput sequence analysis of symptomatic and asymptomatic plant tissue samples revealed near-complete EVE-Georgia (EVE-GA) sequences closely related to caulimoviruses. The analysis of EVE-GA's putative open reading frames (ORFs) compared to cotton virus A and endogenous cotton pararetroviral elements (eCPRVE) revealed their similarity in putative ORFs 1-4. However, in the ORF 5 and ORF 6 encoding putative coat protein and reverse transcriptase, respectively, the sequences from EVE-GA have stop codons similar to eCPRVE sequences from Mississippi. In silico mining of the cotton genome database using EVE-GA as a query uncovered near-complete viral sequence insertions in the genomes of G. hirsutum species (~7 kb) but partial in G. tomentosum (~5.3 kb) and G. mustelinum (~5.1 kb) species. Furthermore, cotton EVEs' episomal forms and messenger RNA (mRNA) transcripts were detected in both symptomatic and asymptomatic plants collected from cotton fields. No significant yield difference was observed between symptomatic and asymptomatic plants of the two varieties evaluated in the experimental plot. Additionally, EVEs were also detected in cotton seeds and seedlings. This study emphasizes the need for future research on EVE sequences, their coding capacity, and any potential role in host immunity or pathogenicity.

Transwell‐Based Microfluidic Platform for High‐Resolution Imaging of Airway Tissues

AbstractTranswell‐based airway models have become increasingly important in studying the effects of respiratory diseases and drug treatment at the air–liquid interface of the lung epithelial barrier. However, the underlying mechanisms at the tissue and cell level often remain unclear, as transwell inserts feature limited live‐cell imaging compatibility. Here, a novel microfluidic platform is reported for the cultivation of transwell‐based lung tissues providing the possibility to alternate between air–liquid and liquid–liquid interfaces. While the air–liquid interface recapitulates physiological conditions for the lung model, the liquid–liquid interface enables live imaging of the tissue at high spatiotemporal resolution. The plastics‐based microfluidic platform enables the insertion and recuperation of the transwell inserts, which allows for tissue cultivation and analysis under standardized well plate conditions. The device is used to monitor infections of Pseudomonas aeruginosa in human stem‐cell‐derived bronchial epithelial tissue. The progression of a P. aeruginosa infection in real‐time at high resolution is continuously imaged, which provides insights into bacterial spreading and invasion on the apical tissue surface, as well as insights into tissue breaching and destruction over time. The airway tissue culture system is a powerful tool to visualize and elucidate key processes of developing respiratory diseases and to facilitate drug testing and development.

Prickle2 regulates apical junction remodeling and tissue fluidity during vertebrate neurulation.

The process of folding the flat neuroectoderm into an elongated neural tube depends on tissue fluidity, a property that allows epithelial deformation while preserving tissue integrity. Neural tube folding also requires the planar cell polarity (PCP) pathway. Here, we report that Prickle2 (Pk2), a core PCP component, increases tissue fluidity by promoting the remodeling of apical junctions (AJs) in Xenopus embryos. This Pk2 activity is mediated by the unique evolutionarily conserved Ser-Thr-rich region (STR) in the carboxyterminal half of the protein. Mechanistically, the effects of Pk2 require Rac1 and are accompanied by increased cadherin dynamics and destabilization of tricellular junctions, the hotspots of AJ remodeling. Notably, Pk2 depletion leads to the accumulation of mediolaterally oriented cells in the neuroectoderm, whereas the overexpression of Pk2 or Pk1 containing the Pk2-derived STR promotes cell elongation along the anteroposterior axis. We propose that Pk2-dependent regulation of tissue fluidity contributes to anteroposterior tissue elongation in response to extrinsic cues.

Uncovering PheCLE1 and PheCLE10 Promoting Root Development Based on Genome-Wide Analysis.

Moso bamboo (Phyllostachys edulis), renowned for its rapid growth, is attributed to the dynamic changes in its apical meristem. The CLAVATA3/EMBRYO SURROUNDING REGION-RELATED (CLE) family genes are known to play crucial roles in regulating meristem and organ formation in model plants, but their functions in Moso bamboo remain unclear. Here, we conducted a genome-wide identification of the CLE gene family of Moso bamboo and investigated their gene structure, chromosomal localization, evolutionary relationships, and expression patterns. A total of 11 PheCLE genes were identified, all of which contained a conserved CLE peptide core functional motif (Motif 1) at their C-termini. Based on Arabidopsis classification criteria, these genes were predominantly distributed in Groups A-C. Collinearity analysis unveiled significant synteny among CLE genes in Moso bamboo, rice, and maize, implying potential functional conservation during monocot evolution. Transcriptomic analysis showed significant expression of these genes in the apical tissues of Moso bamboo, including root tips, shoot tips, rhizome buds, and flower buds. Particularly, single-cell transcriptomic data and in situ hybridization further corroborated the heightened expression of PheCLE1 and PheCLE10 in the apical tissue of basal roots. Additionally, the overexpression of PheCLE1 and PheCLE10 in rice markedly promoted root growth. PheCLE1 and PheCLE10 were both located on the cell membrane. Furthermore, the upstream transcription factors NAC9 and NAC6 exhibited binding affinity toward the promoters of PheCLE1 and PheCLE10, thereby facilitating their transcriptional activation. In summary, this study not only systematically identified the CLE gene family in Moso bamboo for the first time but also emphasized their central roles in apical tissue development. This provides a valuable theoretical foundation for the further exploration of functional peptides and their signaling regulatory networks in bamboo species.

Radiographic Evaluation of Regenerative Endodontic Procedures and Apexification Treatments with the Assessment of External Root Resorption

IntroductionThis multicentered cohort study evaluated the radiographic outcomes of regenerative endodontic procedures (REPs) and apexification treatments (APEX) of immature teeth with endodontic disease. Materials and MethodsThis cohort study included a retrospective record review and prospective data collection of pediatric patients with teeth treated with REPs or APEX between 2005 and 2014. Data including the presence of a periapical lesion, external root resorption, obliteration, apical hard tissue, apical closure, intracanal calcifications, and radiographic root area (RRA) change based on measurements were collected/measured from radiographic images. Univariate and multivariate analyses were conducted. ResultsThe cohort included 190 subjects (204 teeth (92 REPs; 112 APEX)). The frequency of pretreatment periapical pathology was similar between cases in which the clinical treatment failed versus successful treatment cases. However, the frequency of pretreatment external root resorption was higher in failed cases than in successful cases (P = .007). The mean RRA change was greater than twenty percent in 21% of the REPs cases. In traumatized teeth, REPs resulted in less hard tissue formation than other endodontic disease etiologies measured by RRA (P = .001). Fifty-three percent of cases with ERR (16/30) showed signs of healing/arrest and were mostly treated with REPs (11/16). ConclusionsThe presence of ERR negatively affected the treatment outcome. There was significant variability in RRA change in REPs. Signs of healing/arrest of the resorptive lesion were radiographically visible in many cases treated with REPs.

Carbon Nanotubes Induce Mineralization of Human Cementoblasts

IntroductionCarbon nanotubes (CNT) are 1 of the allotropes of carbon with unique properties. CNT shows good bone-tissue compatibility and has been reported to induce osteogenesis; therefore, it is regarded as an ideal material in a wide range of applications. However, the therapeutic effect of CNT-containing materials in the healing of apical periodontal tissue is unknown. The purpose of this study was to clarify the effect of CNT on the proliferation and mineralization of the human cementoblast cell line (HCEM). MethodsThe proliferation of HCEM cells with CNT stimulation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay performed from 24–72 hours. Calcium deposition levels were evaluated by alizarin red S staining on days 7 and 10, and mineralization-related gene expression was examined by quantitative real-time polymerase chain reaction on days 3, 7, and 10. Scanning electron microscopy was used to observe the culture with CNT on day 14. ResultsCNT showed no cytotoxicity to HCEM cell proliferation. Treatment was performed with mineralization medium, CNT-induced HCEM mineralization on day 7, and increased calcium deposition on days 7 and 14. Messenger RNA expression of alkaline phosphatase was significantly increased throughout the experimental period, and bone sialoprotein was significantly increased on day 3 by CNT, whereas no effect was found on mRNA expression of type I collagen. CNT was observed in attachment to the cell surface on day 14. ConclusionsCNT promotes the mineralization of HCEM cells, indicating the potential as a new bioactive component for apical periodontal tissue regeneration materials through the regulation of cementoblast mineralization.

Automated Layer Analysis (ALAn): An Image Analysis Tool for the Unbiased Characterization of Mammalian Epithelial Architecture in Culture.

Cultured mammalian cells are a common model system for the study of epithelial biology and mechanics. Epithelia are often considered as pseudo-two dimensional and thus imaged and analyzed with respect to the apical tissue surface. We found that the three-dimensional architecture of epithelial monolayers can vary widely even within small culture wells, and that layers that appear organized in the plane of the tissue can show gross disorganization in the apical-basal plane. Epithelial cell shapes should be analyzed in 3D to understand the architecture and maturity of the cultured tissue to accurately compare between experiments. Here, we present a detailed protocol for the use of our image analysis pipeline, Automated Layer Analysis (ALAn), developed to quantitatively characterize the architecture of cultured epithelial layers. ALAn is based on a set of rules that are applied to the spatial distributions of DNA and actin signals in the apical-basal (depth) dimension of cultured layers obtained from imaging cultured cell layers using a confocal microscope. ALAn facilitates reproducibility across experiments, investigations, and labs, providing users with quantitative, unbiased characterization of epithelial architecture and maturity. Key features • This protocol was developed to spatially analyze epithelial monolayers in an automated and unbiased fashion. • ALAn requires two inputs: the spatial distributions of nuclei and actin in cultured cells obtained using confocal fluorescence microscopy. • ALAn code is written in Python3 using the Jupyter Notebook interactive format. • Optimized for use in Marbin-Darby Canine Kidney (MDCK) cells and successfully applied to characterize human MCF-7 mammary gland-derived and Caco-2 colon carcinoma cells. • This protocol utilizes Imaris software to segment nuclei but may be adapted for an alternative method. ALAn requires the centroid coordinates and volume of nuclei.

An Innovative Technique for Ejaculation-Sparing Prostatic Enucleation with Thulium:YAG Laser.

Purpose: We report our experience with 100 patients who underwent an innovative prostate enucleation technique that spares the complete urethral-plate from the veru montanum to the bladder neck using a low-energy thulium laser emission. The aim of our study was to evaluate the short-term effects of this procedure on ejaculation preservation and urinary obstruction. Materials and Methods: The International Prostate Symptom Index (IPSS), quality of life (QoL), and Male Sexual Health Questionnaire Ejaculatory Dysfunction (MSHQ-EJD) Short Form were used as validated instruments to quantify ejaculatory dysfunction before and 6 months after the surgery. Results: The median IPSS score pre- and postoperatively was 20 and 5, respectively (p < 0.0001); QoL dropped from a median of 4-1 (p < 0.0001); and the mean preoperative maximal flow rate improved significantly (8.5 vs 21.2 mL/min) (p < 0.0001). Furthermore, there was significant reduction in postvoid residual postoperatively (p < 0.0001). Postoperative ejaculatory function was preserved in 92/100 patients (92%). According to the MSHQ-EJD score, patients reported a slight nonsignificant decrease in frequency of ejaculation (item 1), force of expulsion (item 2) and reduction in semen volume during ejaculation (item 3), with the exception of ejaculation discomfort (item 4). Conclusion: According to our results, complete removal of the apical tissue, which has been advocated as an integral part of the so called ejaculatory hood, does not interfere with ejaculation if the ventral lissosphincter remains intact.

Influence of IgA nephropathy on the progression of pulpitis and apical periodontitis in HIGA mice

ObjectivesImmunoglobulin (Ig)A nephropathy has been associated with oral infections such as periodontitis, but its pathogenesis is not fully understood; no treatments exist. This study analyzes the influence of IgA nephropathy, an autoimmune disease, on the pathogenesis of pulpitis and apical periodontitis. MethodsTwo groups of mice were used in pulp infection experiments: high serum IgA nephropathy model mice (HIGA) and control mice (BALB/c). Histologic analyses of the pulp and apical periodontal tissues were performed on days 3, 5, 7, 14, and 28 following oral bacterial infection. The dynamics of odontoblasts, apoptotic cells, and IgA expression were analyzed using anti-Nestin, TUNEL, and anti-IgA staining, respectively. ResultsInflammatory cells infiltrated the exposed pulp at day three in both groups and by 14 days, these cells had infiltrated from the pulp to the apical periodontal tissue. The area of necrotic pulp tissue increased significantly in the control group at seven days. Odontoblasts decreased from day three onwards and disappeared by 28 days in both groups. The number of apoptotic cells in the pulp and apical periodontal tissues was significantly higher in the experimental group at day 28. The experimental group exhibited a significant increase in IgA production in the pulp after 14 days. Bone resorption in the apical periodontal tissue was significantly decreased in the experimental group at day 28. ConclusionsThe results of this study suggest that IgA nephropathy may modulate the inflammatory response and sustain long-term biological defense responses in pulpitis and apical periodontitis in HIGA mice.

Effect of Recombinant Human Platelet-Derived Growth Factor on Healing of Chronic Periapical Tissue Pathosis Following Apical Surgery in a Canine Model: A Histomorphometric and Microcomputed Tomography Analysis.

This canine in vivo study assessed the effect of recombinant human platelet-derived growth factor (rhPDGF) on the healing of periapical tissues following apical surgery. From a total of 96 premolar teeth, 64 teeth from six beagle dogs (2 years old) were classified as experimental and were randomly assigned to four experimental groups (16 teeth per group). After having the pulp extirpated, leaving teeth open to the oral cavity for 1 week, and sealing with an immediate restorative material for 8 weeks, nonsurgical endodontic treatment was performed. A split-mouth design was used, and intra-animal randomization of treatment sides was applied to the groups as follows: apical curettage + 1.5-mm root-end resection (Group 1); apicoectomy + mineral trioxide aggregate (MTA) root-end filling (Group 2); apicoectomy + MTA root-end filling + rhPDGF (Group 3); and apical curettage + rhPDGF (Group 4). The animals were sacrificed 24 months after apical surgery, and histologic and μCT analyses were performed for bone volume loss (BVL). Group 1 showed partial resolution of the periapical lesions without signs of tissue regeneration (BVL: 49.09 ± 10.97 mm3). Group 2 had minimal bone regeneration and showed cementum reformation in 9 teeth, with no direct attachment to the MTA (BVL: 35.34 ± 10.97 mm3). Group 3 showed regeneration of all damaged apical tissues without direct contact between the cementum and MTA (BLV: 4.51 ± 1.55 mm3). Group 4 showed regeneration of PDL, bone, and cementum and attachment of functional cementum fibers (BVL: 2.82 ± 2.3 mm3). The difference in BVL was statistically significant only for Groups 1 and 2 (P < .05). rhPDGF may help regenerate apical tissue structures following apical surgery.

Abstract 16945: Aberrant Citric Acid Cycle Metabolites Temporally Coincide With Myocardial Dysfunction in a Rat Model of Stress Cardiomyopathy

Introduction: Stress cardiomyopathy is characterized by transient contractile dysfunction with a poorly understood mechanism. Targeting metabolic derangements has proven efficacious in chronic heart failure, but the role of metabolism in acute cardiac dysfunction is ill-defined. Hypothesis: Characterizing any metabolic alterations in stress cardiomyopathy may help identify potential therapeutic targets. Methods: Sprague-Dawley rats (350 ± 57 g) were given a single intraperitoneal injection of 75 mg/kg isoprenaline. Animals were allocated into groups (N=30 each) based on designated time-points for assessment after injection: control (no injection), day 1, 3, and 7. Rats underwent left ventricular PV loop catheterization followed by harvesting of apical ventricular tissue. Targeted metabolomic analyses were performed via LC-MS and supplemented with enzyme activity assays, qPCR, and Western blotting. Results: Stroke work, cardiac output, and ejection fraction were all significantly reduced by day 1 with recovery by day 7 (Figure A, all p&lt;0.05). Targeted tissue metabolomics revealed peaks in nearly all citric acid cycle metabolites, pyruvate, and lactate that similarly correlated with illness (Figure B). In tandem, anaplerotic amino acids rose with injury while tissue triglycerides decreased. Pyruvate dehydrogenase phosphorylation decreased with decreased expression of pyruvate dehydrogenase kinase (Figure C). However, no differences were noted in tissue acylcarnitine levels despite increased serum fatty acids (all p&gt;0.05). Conclusions: Profound rises in citric acid metabolites with accompanying increases in anaplerotic amino acids are suggestive of metabolic reprogramming in the setting of energetic deficits. Notably, these trends differ from those found in chronic heart failure, and represent a novel phenotypic characterization of stress cardiomyopathy with potential therapeutic implications.

Cloning and functional analysis of the BrCUC2 gene in Brassica rapa L.

The CUP-SHAPED COTYLEDON2 (CUC2) gene plays an important role in the formation of apical meristem and organ edges in plants. The apical meristematic tissue of Brassica rapa (B. rapa) is associated with cold resistance, however, the role of the CUC2 gene in cold resistance of B.rapa is unclear. In this study, we used bioinformatics software to analyze the structure of BrCUC2 gene, real-time fluorescence quantitative PCR to detect the expression level of BrCUC2, constructed transgenic Arabidopsis thaliana by the flower dipping method and subcellular localization for functional validation. The results showed that, we isolated a 1104 bp open reading frame of BrCUC2 from the winter B. rapa cultivar 'Longyou 7'. The BrCUC2 contains a highly conserved domain belonging to the NAM superfamily. Its homologus CUC genes contain similar conserved motifs and are closely related to Brassica oleracea (B.oleracea), and the N-terminal of amino acid sequence contains NAC domain. BrCUC2 protein was localized in the nucleus and self-activation tests showed that pGBKT7-BrCUC2 had self-activation. Tissue-specific expression analysis and promoter β-Glucuronidase (GUS) activity showed that BrCUC2 had high expression levels in B. rapa growth points and A. thaliana leaf edges, stems and growth points. After low-temperature stress, BrCUC2 showed greater expression in 'Longyou 7,' which presents strong cold resistance and concave growth points, than in 'Longyou 99,' which presents weak cold resistance and protruding growth points. BrCUC2 promoter contains multiple elements related to stress responses. BrCUC2 overexpression revealed that the phenotype did not differ from that of the wild type during the seedling stage but showed weak growth and a dwarf phenotype during the flowering and mature stages. After low-temperature treatment, the physiological indexes and survival rate of BrCUC2-overexpression lines of Arabidopsis thaliana (A. thaliana) were better than those of the wild type within 12h, although differences were not observed after 24h. These results showed that BrCUC2 improved the low-temperature tolerance of transgenic A. thaliana within a short time. It can provide a foundation for the study of cold resistance in winter B. rapa.

Comparison of Efficacy of Lidocaine and Articaine as Inferior Alveolar Nerve Blocking Agents in Patients with Symptomatic Irreversible Pulpitis: Randomized Controlled Trial.

Background and Objectives: Lidocaine Hydrochloride has been the standard choice for local anesthesia in dentistry and Articaine's unique structure and growing popularity make it a viable alternative. Due to contradictory results in prior research and a scarcity of trials conducted in the Pakistani population, this study aims to compare the anesthetic efficacy of Lidocaine with Articaine for inferior alveolar nerve blocks in patients with symptomatic irreversible pulpitis. Materials and Methods: This double-blinded, randomized controlled trial included 152 patients who were selected by consecutive non-probability sampling. The participants included patients who presented with symptomatic irreversible pulpitis in mandibular posterior teeth (molars and premolars) and depicted normal apical tissue radiographically. The patients were equally and randomly divided into two groups. The control group received 2% Lidocaine Hydrochloride injections, and the experiment group received 4% Articaine Hydrochloride injections. Participants scored their pain on the HP-VAS both before and after the administration of anesthesia. A value of 54 mm or less on the scale indicated effective anesthesia. The data obtained were analyzed using SPSS. Chi-square test was applied to analyze data for statistical significance. Results: There was no statistically significant difference in the efficacy of the two anesthetic agents. During access cavity preparation, Lidocaine demonstrated a success rate of 93%, whereas Articaine exhibited a slightly higher success rate of 97%. During initial instrumentation, the success rates for Lidocaine and Articaine were 72% and 71%, respectively. This suggests that both Lidocaine and Articaine were effective in achieving anesthesia during the dental procedure in patients with symptomatic irreversible pulpitis, with Articaine showing a slightly better success rate, although the difference was not statistically significant. Conclusions: The anesthetic efficacy of Articaine is similar to that of lidocaine in subjects with symptomatic irreversible pulpitis. Hence, Articaine can serve as an alternative to Lidocaine for local anesthesia administration in dentistry.

Comparative transcriptome analysis of genes involved in paradormant bud release response in 'Summer Black' grape.

Grapevines possess a hierarchy of buds, and the fruitful winter bud forms the foundation of the two-crop-a-year cultivation system, yielding biannual harvests. Throughout its developmental stages, the winter bud sequentially undergoes paradormancy, endodormancy, and ecodormancy to ensure survival in challenging environmental conditions. Releasing the endodormancy of winter bud results in the first crop yield, while breaking the paradormancy of winter bud allows for the second crop harvest. Hydrogen cyanamide serves as an agent to break endodormancy, which counteracting the inhibitory effects of ABA, while H2O2 and ethylene function as signaling molecules in the process of endodormancy release. In the context of breaking paradormancy, common agronomic practices include short pruning and hydrogen cyanamide treatment. However, the mechanism of hydrogen cyanamide contributes to this process remains unknown. This study confirms that hydrogen cyanamide treatment significantly improved both the speed and uniformity of bud sprouting, while short pruning proved to be an effective method for releasing paradormancy until August. This observation highlights the role of apical dominance as a primary inhibitory factor in suppressing the sprouting of paradormant winter bud. Comparative transcriptome analysis revealed that the sixth node winter bud convert to apical tissue following short pruning and established a polar auxin transport canal through the upregulated expression of VvPIN3 and VvTIR1. Moreover, short pruning induced the generation of reactive oxygen species, and wounding, ethylene, and H2O2 collectively acted as stimulating signals and amplified effects through the MAPK cascade. In contrast, hydrogen cyanamide treatment directly disrupted mitochondrial function, resulting in ROS production and an extended efficacy of the growth hormone signaling pathway induction.

Effects of Rheumatoid Arthritis on the Progression of Pulpitis and Apical Periodontitis in SKG Mice

IntroductionRheumatoid arthritis (RA) is an autoimmune disease that involves joint inflammation. Although periodontal disease reportedly contributes to RA onset, the associations of RA with pulpitis and apical periodontitis have not been described. The purpose of this study was to examine the effects of immune response disruption of RA for pulpitis and apical periodontitis with SKG mice. MethodsSKG and BALB/c (control) mice were used to establish models of pulp infection. Histologic studies of pulp and apical periodontal tissue were performed at 3, 5, 7, 14, and 28 days; odontoblast dynamics were analyzed by antinestin staining, and apoptotic cells were examined by TdT-mediated digoxygenin (biotin)-dUTP nick end labeling staining. ResultsInflammatory cell infiltration into the exposed pulp was observed at 3 days in the SKG and control group groups; the infiltration extended to the apical pulp area at 14 days after surgery. Inflammatory cell infiltration and bone resorption in the apical pulp area were observed from 14–28 days in the SKG and control groups; there were significant increases in inflammatory cell infiltration and bone resorption in the control group at 28 days. The numbers of apoptotic cells in pulp and apical periodontal tissue were higher in the SKG group than in the control group at 14 and 28 days. The number of odontoblasts decreased in the SKG and control groups until 14 days and then disappeared in the SKG and control groups at 28 days. ConclusionsThis study suggested that immune response disruption in RA is involved in prolonging the inflammatory state of pulpitis and apical periodontitis.

Abstract P3123: Sex-related Differences In Cardiac Biomarkers And Ventricular Fibrosis In A Minipig Model Of Hypertrophic Cardiomyopathy

Hypertrophic Cardiomyopathy (HCM) is characterized by ventricular hypertrophy and stiffness resulting in part from interstitial fibrosis. While associated with autosomal dominant mutations in sarcomere proteins, it has been reported that males and females may have different clinical presentations and disease courses. We have previously shown that minipigs carrying the R403Q mutation in MYH7 demonstrate a phenotype that recapitulates human non-obstructive HCM with increased hypertrophy, markers of cardiac stress, and diastolic dysfunction. Under the hypothesis that sex-dependent differences in cardiac physiology can independently modulate disease phenotype, we evaluated ventricular fibrosis and cardiac biomarkers in both male and female mutant pigs. Purpose-bred Yucatan R403Q MYH7 heterozygous mutant minipigs of either sex (M: n=8, F: n=6) and wild-type littermates (M: n=4, F: n=14) were used; for the purposes of these comparisons, cloned male pigs were also included (R403Q: 8). Males were castrated, and all pigs received soybean-based feed. Circulating levels of both cardiac troponin T (cTnT) and brain natriuretic peptide (BNP), markers of cardiac injury and stress, were assessed. Interstitial fibrosis was assessed in left ventricular free wall (LV-FW) and apical tissue samples utilizing picrosirius red staining and semi-automated quantification (HALO). Male HCM pigs died earlier (&lt;9M of age, P&lt;0.05) and had higher serum biomarkers than females (cTnT levels (M: 143±17 vs F: 44±7 ng/L, P&lt;0.05; BNP 1536±335 vs 4881±414 ng/L, P&lt;0.05) Consistent with the higher cTnT levels, male HCM pigs had greater fibrosis areas than females in both LV-FW (11±3% vs 7±2%, P&lt;0.05) and apical regions (13±1% vs. 8±2%, respectively, P&lt;0.05). All HCM pigs had significantly increased fibrotic area vs WT controls (R403Q: 10±3% vs WT: 3±2%, P&lt;0.05). Our findings demonstrate that despite a common genotype, female and male carriers of the HCM pathogenic R403Q mutation present different disease phenotypes, with castrated males showing greater fibrotic burden. Future studies to understand the mechanistic drivers of these differences should not only help elucidate the role of sex in HCM disease progression, but also the development of sex-informed therapies.

Electroacupuncture improves ischemic myocardial injury by activating Nrf2/HO-1 signaling pathway to inhibit ferroptosis in rats

To explore the role of nuclear factor E2 related factor 2 (Nrf2) / heme oxygenase (HO-1) signal pathway in electroacupuncture (EA) induced improvement of acute myocardial ischemia (AMI) and its relationship with ferroptosis in rats. Male SD rats were randomly and equally divided into sham operation, model, EA and EA+ML385 (inhibitor of Nrf2) groups (n=8). The rat model of AMI was established by ligating the descending anterior branch of the left coronary artery. EA (2 Hz/100 Hz) was applied to bilateral "Shenmen"(HT7) and "Tongli"(HT5) for 20 min, once daily for 7 days. The electrocardiogram (ECG) of standard Ⅱ (ECG ST) lead and heart rate (HR) in each group was recorded and analyzed before and after modeling and after treatment by using PowerLab physiological recorder system. Histopathological changes of myocardial tissue were observed by H.E. staining, and the ultrastructure of myocardiocytes of cardiac apical tissue was observed under transmission electron microscope. The contents of Fe2+ and glutathione (GSH) in the myocardial tissue were measured by chromato-metry. The protein expression levels of Nrf2, HO-1, glutathione peroxidase 4 (GPX4), ferritin heavy chain polypeptide 1 (FTH1) and long chain acyl CoA synthase 4 (ACSL4) in the myocardial tissue were detected by Western blot. Compared with the sham operation group, the HR, ECG ST, Fe2+ content, expression levels of Nrf2, HO-1, FTH1 and ACSL4 proteins in myocardial tissues were significantly increased (P<0.01), while GSH content and GPX4 protein expression considerably decreased (P<0.01) in the model group. Compared with the model group, both EA and EA+ML385 groups had an obvious decrease in HR, Fe2+ content, and ACSL4 levels (P<0.01), and an increase in the expression levels of GPX4 and FTH1 proteins (P<0.01), EA (rather than EA+ML385) effectively down-regulated ECG ST, and up-regulated GSH, Nrf2 and HO-1 (P<0.01), whereas EA+ML385 apparently down-regulated expression levels of Nrf2 and HO-1 (P<0.01). It shows that ML385 pronouncedly weaken the effects of EA in slowing down ECG ST and HR, down-regulating Fe2+ content and ACSL4 expression (P<0.01), up-regulating GSH content, Nrf2, HO-1, GPX4 and FTH1 expressions (P<0.01). H.E. staining showed disordered arrangement and hyperplasia of myocardiocytes, enlarged myocardial fiber gap, agglomerated and deeply stained myoplasma, and some broken myocardial fibers with irregular mass and local tissue fibrosis in the model group, which was relatively milder in both EA and EA+ML385 groups. Compared with the sham operation group, the model group showed decreased mitochondrial atrophy, increased membrane density, and disappearance or reduction of cristae in myocardial cells，which was improved in the EA group. EA of HT7 and HT5 has a protective effect on ischemic myocardium in rats, which may be related to its effects in reducing oxidative stress by regulating Nrf2/HO-1 signaling pathway, and inhibiting "iron death" of myocardial cells.

Establishing and characterizing human stem cells from the apical papilla immortalized by hTERT gene transfer.

Stem cells from the apical papilla (SCAPs) are promising candidates for regenerative endodontic treatment and tissue regeneration in general. However, harvesting enough cells from the limited apical papilla tissue is difficult, and the cells lose their primary phenotype over many passages. To get over these challenges, we immortalized human SCAPs with lentiviruses overexpressing human telomerase reverse transcriptase (hTERT). Human immortalized SCAPs (hiSCAPs) exhibited long-term proliferative activity without tumorigenic potential. Cells also expressed mesenchymal and progenitor biomarkers and exhibited multiple differentiation potentials. Interestingly, hiSCAPs gained a stronger potential for osteogenic differentiation than the primary cells. To further investigate whether hiSCAPs could become prospective seed cells in bone tissue engineering, in vitro and in vivo studies were performed, and the results indicated that hiSCAPs exhibited strong osteogenic differentiation ability after infection with recombinant adenoviruses expressing BMP9 (AdBMP9). In addition, we revealed that BMP9 could upregulate ALK1 and BMPRII, leading to an increase in phosphorylated Smad1 to induce the osteogenic differentiation of hiSCAPs. These results support the application of hiSCAPs in tissue engineering/regeneration schemes as a stable stem cell source for osteogenic differentiation and biomineralization, which could be further used in stem cell-based clinical therapies.