Prevalence of oral submucous fibrosis among areca nut chewers: A systematic review and meta-analysis.

BACKGROUND: Worldwide millions peoples consume AN who are at risk of OSMF. Prevalence of OSMF is reported between 0.03% and 30% irrespective of AN habit. Further, these estimates are based on sample population comprised of OSMF patients or general population rather AN chewers (ANC). Therefore, available evidence does not reflect the true prevalence of OSMF among ANC. METHOD: The studies providing the prevalence of OSMF in ANC were identified in PubMed, Scopus, and Web of Science. Pooled prevalence and quality assessment using New-Ottawa Scale were performed. RESULTS: Fifteen studies reported the prevalence of OSMF (929) in ANC (53,213). Most studies were from China (six studies) and India (four studies) correlating with regions having high ANC. The pooled prevalence of OSMF in ANC was 5% (0.05 [95% CI, 0.03, 0.08]). All studies' quality was satisfactory; however, the OSMF diagnosis method, age, gender, and habits need further scrutiny. CONCLUSION: Available evidence suggested a low prevalence of OSMF in ANC, although further large-scale studies are recommended to validate this finding. Understanding the prevalence and distribution patterns of OSMF might aid intervention healthcare programs and contribute to the reduction of the oral cancer burden related to OSMF.

Salivary stimulatory effect of novel low level transcutaneous electro neurostimulator in geriatric patients with xerostomia.

BACKGROUND: Xerostomia (dryness of the mouth) is one of the most common long-term consequences of ageing, and it causes a tremendous impact on the function and morphology of the salivary ductal system. As a consequence, it leads to a decrease in the amount of salivary output and also affects the overall quality of life. The purpose of this study was to determine whether electrostimulation using a custom designed transcutaneous electrical nerve stimulation (TENS) device will help to improve the quality of secreted saliva following electrostimulation. METHODS: One hundred thirty-five participants underwent the intervention for three months, twice daily (80 Hz). Pre-intervention and post-intervention unstimulated saliva were collected. Parameters such as salivary pH, cortisol level, salivary antioxidants, total protein, the viscosity of saliva, and microbial carriage were analysed. RESULTS: Salivary pH, cortisol, microbial cultures, viscosity, and antioxidants showed a significant difference at the end of the 3rd month (p < 0.05). Irrespective of the patient's age, gender, and common underlying systemic illnesses (diabetes and hypertension), a significant change in the quality of the salivary analytes was observed. CONCLUSION: The study emphasises the use of a custom designed TENS device in improving the quality of secreted saliva among old patients with oral dryness.

Designing Novel Multi-Epitope Vaccine Construct against Prevotella intermedia-Interpain A: An Immunoinformatics Approach.

Background and Objectives: Periodontitis is a chronic multifactorial inflammatory infectious disease marked by continuous degradation of teeth and surrounding parts. One of the most important periodontal pathogens is P. intermedia, and with its interpain A proteinase, it leads to an increase in lethal infection. Materials and Methods: The current study was designed to create a multi-epitope vaccine using an immunoinformatics method that targets the interpain A of P. intermedia. For the development of vaccines, P. intermedia peptides InpA were found appropriate. To create a multi-epitope vaccination design, interpain A, B, and T-cell epitopes were found and assessed depending on the essential variables. The vaccine construct was evaluated based on its stability, antigenicity, and allergenicity. Results: The vaccine construct reached a more significant population and was able to bind to both the binding epitopes of major histocompatibility complex (MHC)-I and MHC-II. Through the C3 receptor complex route, P. intermedia InpA promotes an immunological subunit. Utilizing InpA-C3 and vaccination epitopes as the receptor and ligand, the molecular docking and dynamics were performed using the ClusPro 2.0 server. Conclusion: The developed vaccine had shown good antigenicity, solubility, and stability. Molecular docking indicated the vaccine's 3D structure interacts strongly with the complement C3. The current study describes the design for vaccine, and steady interaction with the C3 immunological receptor to induce a good memory and an adaptive immune response against Interpain A of P. intermedia.

Structure of liganded T-state haemoglobin from cat (Felis silvestris catus), a low oxygen-affinity species, in two different crystal forms.

Haemoglobin (Hb) is an iron-containing metalloprotein which plays a major role in the transportation of oxygen from the lungs to tissues and of carbon dioxide back to the lungs. Hb is in equilibrium between low-affinity tense (T) and high-affinity relaxed (R) states associated with its unliganded and liganded forms, respectively. Mammalian species can be classified into two groups on the basis of whether they express `high' or `low' oxygen-affinity Hbs. Although Hbs from the former group have been studied extensively, a more limited number of structural studies have been performed for low oxygen-affinity Hbs. Here, the crystal structure of low oxygen-affinity cat methaemoglobin (metHb) has been solved at 2.0 and 2.4 Šresolution in two different crystal forms. Even though both structures are fully liganded, they unusually adopt a T-state-like quaternary conformation but with several localized R-like tertiary-structural and quaternary-structural features. The study provides atomic-level insights into the ligand-binding properties of this Hb, including its low cooperativity, blunt response to allosteric effectors and low affinity for oxygen, as well as further contributing to the mechanism underlying Hb allostery.

Glandular odontogenic cyst: Review of literature and report of two cases.

Glandular odontogenic cyst (GOC) is a rare developmental odontogenic cyst from the cell rests of Serres. GOC is locally aggressive with a tendency toward recurrence. The most common site of occurrence is the anterior mandible with an asymptomatic presentation. Radiographically, it presents as unilocular or multilocular radiolucency. It bears histopathological resemblance to low-grade mucoepidermoid carcinoma. We report two cases of GOC occurring in a 16-year-old and a 33-year-old male patient with a review of the clinical presentation, histopathological features, and diagnostic aspects of GOC reported so far in literature.

Dental Anomalies: An Identification Marker in Forensics.

Aim This study aims to evaluate the non-morphological traits of the South Indian population. Introduction Dental morphological traits, also known as non-metric dental traits, exhibit variation in appearance both within and between groups. The study analyzed the non-metric traits among the South Indian population, as few variants can be grouped within the population.  Materials and methods A total of 500 extracted tooth samples were collected. The dental non-metric traits that were evaluated are the cusp of Carabelli (CC), Talon's cusp (TC), shoveled incisor (SI), peg-shaped lateral incisor (PL), protostylid (PR), Dryopithecus pattern groove (DP), hypoconulid (HY), parastyle (PA), multiple parastyle (MPA), paracone (PC), Bushman's canine (BC), interruption groove (IG), tuberculum dentale (TD), tuberculum intermedium (TI), radix entomolaris (RE), fusion (F), radiculous premolar (RP), dilaceration (D), dens evaginatus (DE), and enamel pearl (EP).  Results Out of 20 dental non-metric traits that were evaluated in the study, 14 traits were identified to be common within the population. The prevalence were as follows: cusp of Carabelli (52%), shoveled incisor (8.2%), peg-shaped lateral incisor (7.4%), parastyle (0.8%), multiple parastyle (0.2%), Bushman's canine (0.4%), interruption groove (2.2%), tuberculum intermedium (0.6%), radix entomolaris (39.6%), fusion (2.8%), radiculous premolar (0.2%), dilaceration (58.2%), dens evaginatus (1.2%), and enamel pearl (0.8%) among the South Indian population.  Conclusion The current study was discovered to have more Carabelli traits, shoveled incisors, radix entomolaris, and dilaceration than other non-metric features. This shows that these characteristics are more prevalent in the South Indian population, which could be one of the strategies used to validate human identification in a forensic context.

In Vitro Analysis of Enamel Patterns Across Three Species Using Stereomicroscopy.

Background Dental enamel, the outermost layer of the tooth, stands as a unique and remarkable tissue that plays a crucial role in safeguarding teeth against various external factors. The examination and analysis of enamel rod end patterns on tooth surfaces, referred to as ameloglyphics, offer a promising avenue for dental identification and forensic investigations in forensic medicine, thereby enhancing the precision and reliability of forensic analyses. This paper aims to evaluate and compare the ameloglyphics of different species under a stereomicroscope. The species examined in this study include the beaver (genus Castor), fox (genus Vulpes), and human (Homo sapiens). Methods Teeth samples from each species (n = 3) were gathered from the tooth repository and examined under a stereomicroscope at various magnifications, both with and without graphite staining. Photographs were captured, and the enamel patterns were meticulously evaluated. Through the utilization of plot profiles, the enamel patterns of the different species were compared, and any discernible differences between them were carefully noted. Results The plot profiles of the three species were analyzed, revealing distinct characteristics. Specifically, it was observed that the plots of the genus Castor teeth and Homo sapiens teeth exhibited dispersed arrangements, whereas the plot profile of the genus Vulpes displayed a closely arranged pattern. Conclusions Within the confines of the current investigation, it can be inferred that every mammal exhibits a distinct and exclusive arrangement of enamel rods. Hence, the task of identifying a deceased individual through dental imprints may pose difficulties if the structural characteristics are not thoroughly comprehended.

Prediction of the Need for Anticonvulsants in the Management of Orofacial Neuropathic Pain Using Machine Learning.

Background and aim Orofacial neuropathic pain is a medical condition caused by a lesion or dysfunction of the nervous system and is one of the most challenging for dental clinicians to diagnose. Anticonvulsants, antidepressants, analgesics, nonsteroidal anti-inflammatory drugs, and other classes of medications are frequently used to treat this condition. Our study aimed to build a machine learning-based classifier to predict the need for anticonvulsant drugs in patients with orofacial neuropathic pain. Materials and methods A machine learning tool that was trained and tested on patients for predicting and detecting algorithms, which would in turn predict the need for anticonvulsants in the treatment of orofacial neuropathic pain, was employed in this study. Results Three machine learning algorithms successfully detected and predicted the need for anticonvulsants to treat patients with orofacial neuropathic pain. All three models showed a high accuracy, that is, 97%, 94%, and 89%, in predicting the need for anticonvulsants. Conclusion Machine learning algorithms can accurately predict the need for anticonvulsant drugs for treating orofacial neuropathic pain. Further research is needed to validate these findings using larger sample sizes and imaging modalities.

Weighted Gene Co-expression Network Analysis (WGCNA) of Wnt Signaling Related to Periodontal Ligament Formation: A Bioinformatics-Based Analysis.

Introduction The Wnt signaling pathway is crucial for tooth development, odontoblast differentiation, and dentin formation. It interacts with epithelial cadherin (E-cadherin) and beta-catenin in tooth development and periodontal ligament (PDL) formation. Dysregulation of Wnt signaling is linked to periodontal diseases, requiring an understanding of therapeutic interventions. Weighted gene co-expression network analysis (WGCNA) can identify co-expressed gene modules. Our study aims to identify hub genes in WGCNA analysis of Wnt signaling-based PDL formation. Methods The study used a microarray dataset GSE201313 from the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus to analyze the impact of DMP1 expression on XLH dental pulp cell differentiation and PDL formation. The standardized dataset was used for WGCNA analysis, which generated a co-expression network by calculating pairwise correlations between genes and constructing an adjacency matrix. The topological overlap matrix (TOM) was transformed into a hierarchical clustering tree and then cut into modules or clusters of highly interconnected genes. The module eigengene (ME) was calculated for each module, and the genes within this module were identified as hub genes. Gene ontology (GO) and KEGG pathway enrichment analysis were performed to gain insights into the biological functions of the hub genes. The integrated Differential Expression and Pathway analysis (iDEP) tool (http://bioinformatics.sdstate.edu/idep/; South Dakota State University, Brookings, USA) was used for WGCNA analysis. Results The study used the WGCNA package to analyze 1,000 differentially expressed genes, constructing a gene co-expression network and generating a hierarchical clustering tree and TOM. The analysis reveals a scale-free topology fitting index R2 and mean connectivity for various soft threshold powers, with an R2 value of 5. COL6A1, MMP3, BGN, COL1A2, and FBN2 are hub genes implicated in PDL development. Conclusion The study identified key hub genes, including COL6A1, MMP3, BGN, and FBN2, crucial for PDL formation, tissue remodeling, and cell-matrix interactions, guiding future therapeutic strategies.

Weighted Gene Co-expression Network Analysis of the Inflammatory Wnt Signaling Reveals Biomarkers Related to Bone Formation.

Background and aim Osteocytes regulate bone metabolism and balance through various mechanisms, including the Wnt (Wingless-related integration site signal transduction) signaling pathway. Weighted gene co-expression network analysis (WGCNA) is a computational method to identify functionally related genes based on expression patterns, especially in the Wnt-beta-catenin and osteo-regenerative pathways. This study aims to analyze gene modules of the Wnt signaling pathway from WGCNA analysis. Methods The study used a microarray dataset from the GEO (GSE228306) to analyze differential gene expression in human primary monocytes. The study standardized datasets using Robust Multi-Array Average (RMA) expression measure and Integrated Differential Expression and Pathway (IDEP) analysis tool, building a co-expression network for group-specific component (GC) genes. Results The study uses WGCNA to identify co-expression modules with dysregulated mRNAs, revealing enrichment in Wnt-associated pathways and top hub-enriched genes like colony-stimulating factor 3 (CSF3), interleukin-6 (IL-6), IL-23 subunit alpha (IL23A), suppressor of cytokine signaling 1 (SOCS1), and C-C motif chemokine ligand 19 (CCL19). Conclusion WGCNA analysis of the Wnt signaling pathway will involve functional annotation, network visualization, validation, integration with other omics data, and addressing method limitations for better understanding.

Variational Autoencoders for Generative Drug-Gene Interactions in Periodontal Bone Resorption.

Introduction Periodontal bone resorption is a significant dental problem causing tooth loss and impaired oral function. It is influenced by factors such as bacterial plaque, genetic predisposition, smoking, systemic diseases, medications, hormonal changes, and poor oral hygiene. This condition disrupts bone remodeling, favoring resorptive processes. Variational autoencoders (VAEs) can learn the distribution of drug-gene interactions from existing data, identify potential drug targets, and predict therapeutic effects. This study investigates the generation of drug-gene interactions in periodontal bone resorption using VAEs. Methods A bone resorptive drugs dataset was retrieved from Probes and Drugs and analyzed using Cytoscape (https://cytoscape.org/) and CytoHubba (https://apps.cytoscape.org/apps/cytohubba), powerful tools for studying drug-gene interactions in bone resorption. The dataset was then prepared for matrix representation, with normalized input data. It was subsequently divided into training, validation, and testing sets. We then built an encoder-decoder network, defined a loss function, optimized parameters, and fine-tuned hyperparameters. Using VAEs, we generated new drug-gene interactions, assessed model performance, and visualized the latent space with reconstructed drug-gene interactions for further insights. Results The analysis revealed the top hub genes in drug-gene interactions, including Matrix Metalloproteinase (MMP) 14, MMP 9, HIF1A, STAT1, MAPT, CAS9, MMP2, CASP3, MMP1, and MAK1. The VAE's reconstruction accuracy was measured using mean squared error (MSE), with an average squared difference of 0.077. Additionally, the KL divergence value was 2.349, and the average reconstruction log-likelihood was -246. Conclusion The generative variational encoder model for drug-gene interactions in bone resorption demonstrates high accuracy and reliability in representing complex drug-gene relationships within this context.

A case report of chronic intermedullary inflammation of bone in a child.

Osteolytic lesions refer to the destruction of any part of bone due to a disease process (pertaining to dissolution of bone, especially loss of calcium). Osteomyelitis is the inflammation of the bone caused by an infecting organism. Although bone is normally resilient to bacterial colonization, events such as trauma, surgery, infections, the presence of foreign bodies, and anemia may disrupt bony integrity and lead to the onset of bone infections. Sometimes, osteomyelitis causes no signs and symptoms or the signs and symptoms are hard to distinguish from other problems. This may be true for children, older adults, and people whose immune systems are compromised. Here, we report a case of chronic intermedullary inflammation of bone in a child.

Estimation of Tooth Dimensions and Golden Divine Ratio in Extracted Human Permanent Maxillary and Mandibular Canines in a Cohort of Tamil Ethnicity.

Background Teeth serve many functions, and aesthetics is one of the most important aspects served by teeth, perceived by the limbic system of the human brain. The golden divine ratio is the unique proportion often correlated with beauty. The present study was devised to estimate the dimension of human permanent canines and approximation to the golden divine ratio. Materials and methods The present study included 47 extracted human permanent canines retrieved from the tooth repository of our institute's Department of Oral Biology. Using digital vernier calipers (Themisto TH-M61 digital vernier caliper, 0-150mm/ 6 inch, JIPVI Ecommerce Pvt. Ltd, India, 2022), the following measurements were taken: Mesio-distal and labiolingual dimensions of the crown, crown length, root length, root to crown ratio (R/C) and the tooth to root ratio (T/R). The data were analyzed using Statistical Package for Social Sciences (SPSS) software version 26. Results All the dimensions' mean and standard deviations were calculated for both maxillary and mandibular canines. While the means of mesio-distal and labiolingual dimensions of the crown approximated the values reported in the literature, there was some variation in crown and root lengths. The mean crown lengths of the upper and lower canines were 10.34mm and 9.76mm, respectively, while the root lengths were 16.52 and 15.54mm, respectively. The R/C of both sets and the T/R of the upper canine only followed the golden ratio. T/R of the lower canine was slightly higher (1.64) Conclusion Although the number of included teeth was less, owing to the fact that canines are rarely extracted, our results provided new values of canines for updation in a unique population. More studies are required for comparative anthropological data updates.

Interactions of Acetyl-11-Keto-Beta-Boswellic Acid on Catechol-O-Methyltransferase in the Management of Masticatory Myofascial Pain Syndrome.

BACKGROUND: Masticatory myofascial pain syndrome (MMPS) is a soft tissue inflammatory disorder that leads to acute or chronic localized pain and stiffness in the muscles. Catechol-O-methyltransferase (COMT) plays a crucial role in mediating pain perceptions in humans by transferring methyl groups to catecholamines. This process requires adequate S-adenosyl methionine (SAMe). A reduction in SAMe leads to COMT inhibition. Boswellia serrata possesses multiple therapeutic benefits and is used for treating chronic pain. AIM: The study aimed to evaluate the therapeutic potential of acetyl-11-keto-beta-boswellic acid (AKBA) by targeting COMT. Methodology: Molecular docking and dynamic simulations were conducted using Desmond software from Schrödinger LLC, USA, to evaluate the interaction between COMT protein and AKBA ligands. The COMT protein structure was sourced from the Protein Data Bank and preprocessed using optimized potentials for liquid simulations. Molecular docking identified potential binding sites between COMT and AKBA through hydrogen bonding, resulting in a docking score of -6.0 kcal/mol. RESULTS: The molecular docking revealed a docking score of -6.0 kcal/mol for the interaction between COMT and AKBA. The dynamic simulation demonstrated that the COMT-AKBA complex remained stable within a 3.0 Angstrom range over 60 nanoseconds. These findings indicate stable natural small molecular interactions between COMT and AKBA. CONCLUSION: AKBA exhibits potential as a therapeutic agent for MMPS, demonstrating stable interactions with COMT. These findings warrant further in vitro and in vivo analyses to confirm efficacy.

Comparative Quantification of Fungiform Papillae Density and Taste Perception in Anemic and Healthy Controls: A Case-Control Study.

Background Taste perception is crucial for dietary choices, nutrition, and overall health. The human tongue, particularly the fungiform papillae, plays a significant role in taste sensation, especially for sweet and umami flavors. Anemia, a common condition characterized by low hemoglobin levels, can affect sensory perception, including taste. Recent research has begun to explore the relationship between fungiform papillae density and taste perception in individuals with anemia. Objective This study aimed to investigate the comparative quantification of fungiform papillae density and its correlation with taste perception in anemic and healthy individuals, with the goal of understanding the underlying mechanisms linking anemia to taste disturbances. Methods A total of 100 adults (50 anemic and 50 healthy controls) aged 18-65 participated in the study. Demographic data, dietary habits, and medical history were collected. Taste perception was assessed using a taste strip test and psychophysical scaling methods, including magnitude estimation and the method of constant stimuli. Fungiform papillae density was quantified using high-resolution images of the tongue. Statistical analyses, including t-tests and correlation analyses, were conducted to compare the groups and explore relationships between hemoglobin levels, papillae density, and taste perception. Results The study found that anemic individuals had a slightly lower mean fungiform papillae density (49 papillae per square centimeter) compared to healthy controls (57 papillae per square centimeter). In the taste strip test, anemic participants showed reduced accuracy in taste perception, particularly for bitter flavors. However, psychophysical scaling results, as measured by magnitude estimation, revealed no statistically significant difference in subjective taste intensity between the anemic and healthy control groups (p=0.8666). Conclusion The study suggests that while anemic individuals may exhibit reduced fungiform papillae density and altered taste perception, particularly for bitter flavors, the overall subjective perception of taste intensity does not significantly differ from that of healthy controls. These findings contribute to the understanding of taste disturbances in anemia and may inform future diagnostic and therapeutic approaches for managing taste disorders in affected individuals.

Quantification of the Anti-diabetic Effect of Allium cepa.

BACKGROUND: Allium cepa, or onion, boosts numerous health benefits, including anti-diabetic effects. Its rich array of antioxidants and sulfur compounds not only aids heart health by lowering cholesterol and blood pressure but also exhibits anti-inflammatory properties. Onion's antibacterial and antiviral properties help combat infections, while its compounds like quercetin show promise in cancer prevention. Additionally, Allium cepa supports respiratory health by relieving coughs and colds and aids digestion with its prebiotic properties. Incorporating onions into a balanced diet can enhance overall well-being, including managing blood sugar levels in individuals with diabetes. AIM AND OBJECTIVE: This study aims to determine if the ethanolic extract from the dried peel of Allium cepa holds potential as an anti-diabetic agent, with a focus on its ability to manage diabetes and reduce blood sugar levels. METHODOLOGY: To prepare the ethanolic extract from dried onion peel, the peel was finely ground and soaked in ethanol. The mixture was then agitated and filtered to separate the liquid extract. Finally, the filtrate was concentrated using methods such as rotary evaporation or vacuum distillation to obtain a concentrated extract for further analysis like alpha-amylase inhibition assay and alpha-glucosidase inhibition assay. RESULTS: The ethanolic extracts derived from dried onion peel demonstrate inhibition of alpha-glucosidase, leading to reduced blood glucose levels. Additionally, this inhibition prompts an increase in insulin production. CONCLUSION: The study underscores that the efficacy of the ethanolic extract of dried onion peel increases with concentration. It highlights the presence of beneficial compounds like total phenolics, flavonoids, quercetin, and its derivatives in onion peel, known for their therapeutic roles in cardiovascular health, weight management, diabetes control, cancer prevention, and antimicrobial activity. These findings affirm the hypoglycemic and anti-diabetic properties of Allium cepa's ethanolic leaf extract.

Evaluation of CD44 antigen in type 2 diabetic patients with periodontitis: An immunohistochemical study.

BACKGROUND: Type 2 diabetes mellitus (DM) is a known systemic risk factor for periodontitis. An increased expression of CD44 has been suggested in type 2 diabetics and periodontitis patients. OBJECTIVES: The present study aimed to assess the expression of CD44 antigen in patients with chronic periodontitis (CP) and type 2 DM in a South Indian urban population. Additionally, the relationships between the expression of CD44 antigen in gingival tissues, periodontal clinical parameters, and the random blood sugar (RBS) and glycated hemoglobin (HbA1c) levels were assessed. MATERIAL AND METHODS: A total of 63 subjects were divided into 3 groups: systemically and periodontally healthy controls (group H); CP patients, otherwise healthy (group CP); and CP patients with type 2 DM (group CP+DM). Periodontal parameters were recorded for all groups, and additionally the RBS and HbA1c levels for group CP+DM. Gingival tissue samples were obtained and subjected to immunohistochemical analysis for CD44. RESULTS: The expression of CD44 was significantly higher in the diseased groups. Epithelial CD44 expression was significantly stronger in group CP+DM as compared to groups CP and H (p < 0.001), whereas connective tissue CD44 expression was similar in groups CP and CP+DM (p = 0.657). Furthermore, an inverse relationship was observed between blood glucose parameters and CD44 expression in the epithelium and connective tissue. CONCLUSIONS: The expression of CD44 increased with the severity of periodontal disease. Additionally, glycemic control in patients with CP and type 2 DM had an impact on CD44 expression. Our findings indicate a possible destructive role of CD44 in the pathogenesis of periodontal diseases in individuals with type 2 DM.

Molecular Insights of an Avian Species with Low Oxygen Affinity, the Crystal Structure of Duck T-State Methemoglobin.

Hemoglobin (Hb) is the key metalloprotein within red blood cells involved in oxygen transportation from lungs to body cells. The heme-iron atom inherent within Hb effectuates the mechanism of oxygen transportation and carbon dioxide removal. Structural investigations on avian Hb are limited when compared with the enormous work has been carried out on mammalian Hb. Here, the crystal structure of T-state methemoglobin (T-metHb) from domestic duck (Anas platyrhynchos), a low oxygen affinity avian species, determined to 2.1Å resolution is presented. Duck T-metHb crystallized in the orthorhombic space group C2221 with unit cell parameters a = 59.89, b = 109.42 and c = 92.07Å. The final refined model with R-factor: 19.5% and Rfree: 25.2% was obtained. The structural analysis reveals that duck T-metHb adopts a unique quaternary structure that is distinct from any of the avian liganded Hb structures. Moreover, it closely resembles the deoxy Hb of bar-headed goose, a high oxygen-affinity species. Besides the amino acid αPro119 located in the α1ß1 interface, a unique quaternary structure with a constrained heme environment is attributed for the intrinsic low oxygen-affinity of duck Hb. This study reports the first protein crystal structure of low oxygen-affinity avian T-metHb from Anas platyrhynchos.

Phytochemical Targeting of Nerve Growth Factor by Thymoquinone and Cuscutin: A Molecular Dynamics Simulation Study.

Background Nerve growth factor (NGF) is a novel target of pain therapeutics for oral cancer, and it plays a main role in the nociception of chronic pain. Surgery, along with chemotherapy or radiotherapy, is the gold standard for treating patients, but the side effects are significant as well. Newer effective interventions with natural phytochemicals could improve patient compliance and enhance the quality of life among patients with oral cancer. A literature search revealed a positive correlation between NGF and oral cancer pain. Nigella sativa (N. sativa) and Cuscuta reflexa (C. reflexa) have proven anticancer effects, but their activity with NGF is unexplored. Aims and objectives We aimed to identify the potential phytochemicals in N. sativa and C. reflexa. We also checked the NGF-blocking activity of the phytochemicals. Molecular docking and molecular dynamic (MD) simulations evaluated the binding energy and stability between the NGF protein and selected phytochemical ligands. Materials and methods We obtained protein NGF structure from UniProt (ID: 4EDX, P01138, Beta-nerve growth factor), ligand (thymoquinone) structure using PubChem ID: 10281, and ligand (cuscutin) structure using PubChem ID: 66065. Maestro protein (Schrödinger Inc., Mannheim, Germany) was used for molecular docking. Desmond Simulation Package (Schrödinger Inc., Mannheim, Germany) was used to model MD for 100 nanoseconds (ns). We have assessed the interaction between the protein and ligands by root mean square deviation (RMSD) values.  Results The interaction of thymoquinone and cuscutin with NGF was assessed. While interacting with thymoquinone, there was mild fluctuation from 0.6 Å to 2.5 Å up to 80 ns and ended up at 4.8 Å up to 100 ns. While interacting with cuscutin, mild fluctuation was seen from 0.8 Å to 4.8 Å till 90 ns and ended at 6.4 Å up to 100 ns. We found a stable interaction between our drug combination and the NGF receptor. Conclusion We have identified a stable interaction between thymoquinone, cuscutin, and NGF by our MD simulations. Hence, it could be used as an NGF inhibitor for pain relief and to control tumor progression. Further in vitro and in vivo evaluations of this novel drug combination with phytochemicals will help us understand their biological activities and potential clinical applications in oral cancer therapeutics.

Validation of Age Estimation Using the Compositional Variation of Dental Hard Tissue: An X-ray Diffraction Analysis.

Introduction X-rays and X-ray diffraction (XRD) are two non-destructive techniques that determine a material's crystallographic structure, chemical composition, and physical properties. They can also be used to estimate a person's age when it is unknown, assess the need for orthodontic treatment, or predict the likelihood of tooth decay. This research aims to validate the accuracy of age estimation through X-ray diffraction analysis of tooth hard tissue with compositional changes. Methodology Four tooth samples were analyzed using the Pan Analytical XRD (Malvern Panalytical Ltd., UK) unique d8 family platform, which uses Cu Kα radiation (0.154 nm) and a 0.02° scan rate from 0 to 80°. Results The angle of incidence (ω) is established between the sample and the X-ray source. The angle of diffraction, 2θ, is established between the detector and the incident beam. The detector angle 2θ and the incident angle ω always equal half. Inter-atomic distance, or d-spacing (D = 10^-8 cm in Angstrom units), is measured. A greater crystal size or a greater degree of crystallinity may be indicated by a higher peak intensity, which translates to an increased amount of atoms in the crystal. Conclusion The study's findings suggest that XRD is a promising new technique for age determination, as it has an advanced and dynamic approach to finding the crystallographic characteristics of the provided sample.