Bond strength of lithium disilicate to polyetheretherketone.

STATEMENT OF PROBLEM: Polyetheretherketone (PEEK) is a high-performance polymer that is increasingly used in dentistry, for example, as a framework for implant-supported fixed complete dentures. One protocol calls for individual lithium disilicate crowns to be cemented on preparation-shaped retentive elements on the framework. However, the flexibility and strength of the bonded system is unclear. PURPOSE: The purpose of this in vitro study was to compare the flexibility and strength of bonded lithium disilicate to PEEK with the bond between lithium disilicate and zirconia. MATERIAL AND METHODS: Fifteen PEEK (JUVORA Dental Disc), 15 zirconia (ArgenZ HT+), and 30 lithium disilicate (IPS e.max CAD) beam-shaped specimens (12.5×2×2 mm) were prepared. The ends of the PEEK beams were conditioned with 50-µm aluminum oxide airborne-particle abrasion, followed by primer (visio.link) and light-activated polymerization. Zirconia specimens were prepared with airborne-particle abrasion and primer (Monobond Plus). Lithium disilicate specimens were etched with 4.5% hydrofluoric acid (IPS Ceramic Etching Gel) and primed (Monobond Plus). The lithium disilicate specimens were cemented (Multilink Automix) to the PEEK and zirconia specimens. Light- and chemical-activated polymerization were used. Monolithic specimens of PEEK and zirconia (25×2×2 mm) were also prepared. All specimens were stored overnight in distilled water and submitted to a 4-point bend test in a universal testing machine at 0.5 mm/min crosshead speed until fracture, and the flexural modulus and strength were calculated. Differences among groups were statistically tested by using 1-way analysis of variance followed by the Student-Newman-Keuls post hoc test (α=.05). RESULTS: All bonded specimens fractured at their adhesive interface. Zirconia bonded to lithium disilicate specimens (29.7 ±8.8 MPa) were approximately 3 times stronger than PEEK bonded to lithium disilicate specimens (10.4 ±2.7 MPa) and approximately 12 times more rigid (78.5 ±6.7 GPa and 6.5 ±1.8 GPa, respectively). The flexure of monolithic PEEK was such that it did not fracture when loaded at 0.5 mm/min, while zirconia fractured at 413.9 ±38.5 MPa. Monolithic PEEK was approximately 37 times more flexible than monolithic zirconia (4.3 ±0.3 GPa and 157.2 ±7.2 GPa, respectively). All values were statistically significantly different except between the flexural moduli of monolithic PEEK and PEEK bonded to lithium disilicate. CONCLUSIONS: The bond strength between PEEK and lithium disilicate was significantly weaker than between zirconia and lithium disilicate. Monolithic zirconia was significantly stiffer than monolithic PEEK.

Does Graft Particle Type and Size Affect Ridge Dimensional Changes After Alveolar Ridge Split Procedure?

PURPOSE: The absence of an adequate volume of bone at implant sites requires augmentation procedures before the placement of implants. The aim of the present study was to assess the ridge width gain with the use of allografts and biphasic ß-tricalcium phosphate with hydroxyapatite (alloplast) in ridge split procedures, when each were used in small (0.25 to 1 mm) and large (1 to 2 mm) particle sizes. PATIENTS AND METHODS: A randomized controlled trial of 23 subjects with severe atrophy of the mandible in the horizontal dimension was conducted in a private institute. The patients underwent placement of 49 dental implants after a staged ridge split procedure. The patients were randomly allocated to alloplast and allograft groups (predictor variable). In each group, the patients were randomly assigned to either small graft particle or large graft particle size (predictor variable). The gain in ridge width (outcome variable) was assessed before implant placement. A 2-way analysis of variance test and the Student unpaired t test were used for evaluation of the ridge width gain between the allograft and alloplast groups (predictor variable). Differences were considered significant if P values were < .05. RESULTS: The sample included 23 patients (14 men and 9 women). The patients were randomly allocated to the alloplast (n = 11) or allograft (n = 12) group before the ridge split procedure. In each group, they were assigned to a small graft particle or large graft particle size (alloplast group, small particle in 5 and large particle size in 6 patients; allograft group, small particle in 6 and large particle size in 6). A statistically significant difference was observed between the 2 graft types. The average ridge width gain was significantly greater in the alloplast group (large, 4.40 ± 0.24 mm; small, 3.52 ± 0.59 mm) than in the allograft group (large, 3.82 ± 0.19 mm; small, 2.57 ± 0.16 mm). For both graft types (alloplast and allograft), the large particle size graft resulted in a greater ridge width gain compared with the small particle size graft (P < .05). CONCLUSIONS: Within the limitations of the present study, we suggest the use of large particle alloplast as the graft material of choice for staged ridge split procedures in the posterior mandible.

Replicating a discolored tooth preparation: A technique for effective laboratory communication.

Fabricating a ceramic restoration for a discolored anterior tooth presents a clinical challenge. The dental technician is often hampered by being unaware of the shade of the discolored tooth preparation, which influences the color of the overlying ceramic restoration. A definitive cast that replicates the shade of the prepared tooth helps the ceramist to fabricate a restoration that masks the discoloration appropriately and still achieves the desired optical properties. This report demonstrates the use of a technique of recording and communicating the shade of a prepared tooth to the dental laboratory technician.

Evaluation of Effectiveness of Cement Removal From Implant-Retained Crowns Using a Proposed "Circular Crisscross" Flossing Technique.

Extruded cement during dental implant crown cementation may cause peri-implant diseases if not removed adequately. The purpose of this study was to evaluate the efficiency of removal of cement after cementation of implant crowns using an experimental circular crisscross flossing technique (CCFT) flossing technique, compared to the conventional "C"-shape flossing technique (CSFT). Twenty-four patients rendered 29 experimental and 29 control crowns. Prefabricated abutments were secured to the implant such that the margins were at least 1 mm subgingivally. The abutments were scanned using computer-aided design/computer-aided manufacturing technology and Emax crowns were fabricated in duplicates. Each crown was cemented individually and excess cement was removed using the CSFT and the CCFT techniques. After completion of cementation was completed, the screw access holes were accessed and the crown was unscrewed along with the abutment. The samples were disinfected using 70% ethanol for 10 minutes. Crowns were divided into 4 parts using a marker to facilitate measurement data collection. Vertical and horizontal measurements were made for extruded cement for each control and experimental groups by means of a digital microscope. One-hundred and seventeen measurements were made for each group. Mann-Whitney test was applied to verify statistical significance between the groups. The CCFT showed a highly statistically significant result (104.8 ± 13.66, P < .0001) for cement removal compared with the CSFT (291.8 ± 21.96, P < .0001). The vertical measurements of the extruded cement showed a median of 231.1 µm (IQR = 112.79-398.39) and 43.62 µm (IQR = 0-180.21) for the control and the experimental flossing techniques, respectively. The horizontal measurements of the extruded cement showed a median of 987.1 µm (IQR = 476.7-1,933.58) and 139.2 µm (IQR = 0-858.28) for the control and the experimental flossing techniques, respectively. The CCFT showed highly statistically significant less cement after implant crowns cementation when compared with the CSFT.

Shark Fin Titanium Hollow Bulb Obturator: A Treatment Concept.

Restoring esthetics and function for patients with maxillectomy defects presents a complex challenge for the clinician. Obturator prostheses are subject to rotational forces during function, allowing movement into the defect. Gaining prosthesis support from endosseous implants can limit the amount of rotation. Xerostomia and impaired tissue healing caused by radiation therapy further complicates the treatment for such patients. Several resilient and rigid obturator design concepts are available for restoration of such defects. This clinical report describes a design concept used to treat a patient with a maxillectomy defect caused by tumor resection secondary to a squamous cell carcinoma.

Managing maxillary proclination with novel designed angulated implants.

Implant-supported removable dental prostheses may be supported by a variety of splinted (bar and clip) attachment systems or nonsplinted abutment-based attachments (ball, magnets, and resilient stud attachments such as locators [Zest Anchors], ERA [Sterngold], and nonresilient-stud attachments such as ANKYLOS SynCone [Dentsply Implants]). Nonsplinted attachments are preferred as they are more economical, less technique sensitive, easier to clean, repair, and maintain than splinted (bar and clip) attachment systems, but they work favorably only when implants in the arch are placed parallel to each other. Often implants in the anterior maxilla have to be placed with a labial inclination (due to the proclination of the premaxilla), resulting in lack of parallelism between the anterior and posterior implants, making it challenging to fabricate a removable dental prostheses supported by nonsplinted attachments, and necessitating the use of angled abutments. Recently, a novel implant design with a 12° restorative platform angulation has been introduced by Southern Implants (Co-axis, Keystone Dental, Inc., Burlington, MA, USA). These new angulated implants aid in minimizing the divergence between the anterior and posterior maxillary implants without using angled abutments. The purpose of this article was to report a case utilizing the novel angulated implants (Co-axis, Keystone Dental, Inc., Burlington, MA, USA) in the premaxilla for fabrication of maxillary removable dental prostheses supported and retained by nonsplinted attachments.

Defining the posterior palatal seal on a definitive impression for a maxillary complete denture by using a nonfluid wax addition technique.

The posterior palatal seal area is defined as the soft tissue area at or beyond the junction of the hard and soft palates on which pressure within physiologic limits can be applied by a removable complete denture to aid in its retention. The retention of the maxillary denture is affected by the extent and the design of the posterior palatal seal. This article discusses a method of defining the posterior palatal seal on a definitive impression for a maxillary complete denture by using microabrasion and a nonfluid wax addition technique.

A screw-connected sectional impression tray for patient with limited opening.

A procedure for fabricating a 2-piece custom tray is described. Implant analogs and gold cylinders are used to maximize the precision of the fit and the stability of the tray.

Design, optimization, and evaluation of topical gel of Cardiospermum halicacabum and Ricinus communis L. leaves extract for the treatment of rheumatoid arthritis.

This research aims to develop and assess the anti-arthritic properties of a topically herbal gel including leaf extracts from Cardiospermum halicacabum and Ricinus communis L. in rats. Utilizing gelling agents carbopol 940 (2.5, 5, 7.5 g), nine herbal gel compositions were created. Prepared formulations were then assessed for physical appearance, spreadability, viscosity, net content, pH, extrudability, in vitro diffusion profile, and main skin irritant tests. According to the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) recommendations, the stability research for the topical herbal gel composition was completed, and Freund's Complete Adjuvant (FCA) induced arthritis technique was used to assess the anti-arthritic efficacy. Additional procedures included measuring the body weight, paw volume, biochemical and hematological variables, histological analysis, and in vitro serum biomarker detection. The prepared gels followed the instructions and were uniform and stable. F5 performed better than the other compositions in terms of release kinetics (97.20%). The gel proved safe and non-toxic since no erythema or edema was seen during the skin irritation test. Comparing the herbal gel F5 comprising carbopol 940 to rats with arthritis, the topical treatment showed considerable (p < .001) anti-arthritic effect. The anti-arthritic action of the gel formulations was confirmed by decreased paw volume, absence of agglutination in reacting protein and rheumatic factor, a decline in TNFα level, restoration to baseline biochemical and hematological characteristics, decrease in thymus and spleen weight, and histopathological study.

Coarse grained MD simulation of bulk and interfacial behavior of mixture of CTAB/SDS surfactants.

CONTEXT: This study involves simulating the process of inhibiting corrosion through the formation of micelles by surfactants and their deposition on iron (Fe) surfaces. The primary focus is on examining CTAB/SDS mixtures in aqueous solutions with different concentrations. Micelle properties, including size, shape, aggregation number, cluster size, and surfactant diffusion, were calculated and validated with experimental data. The coarse-grained Fe surface was modeled and validated against experimental water contact-angle data. Subsequently, the deposition of CTAB/SDS mixtures on the Fe surface and air-water interface was studied systematically. We found that the relative ratio of CTAB/SDS in the solution directly influences surfactant deposition behavior, which might impact the corrosion inhibition efficiency. METHODS: All the MD simulations were performed using the GROMACS software with MARTINI2 force field and Martini polar water. The molecules are packed using PACKMOL software. Both NVT and NPT simulations are caried out at temperature and pressure of 303 K and 1 bar respectively, with a nonbonded interaction cut-off (rcut) of 1.1 nm. The LJ potential was shifted from 0.9 nm to rcut, while the electrostatic potential was shifted from 0.0 nm to rcut. For electrostatics, reaction-field coulomb type is used, relative dielectric constant (epsilon-r) and the reaction field dielectric constant (epsilon-rf) are equal to 2.5 and infinity respectively. The dielectric constant below rcut is epsilon-r, and beyond the cut-off is epsilon-rf. Coulomb-modifier used as potential-shift which leads to shift in the coulomb potential by a constant such that it is zero at the rcut. This makes the potential of the integral of the force . The neighbor list was updated every 10 steps, employing a neighbor list cut-off equal to rcut. Using a polar water model, we used a constant time step of 0.02 ps throughout the simulation. The used epsilon-r = 2.5, is recommended for polar water.

Stem cells in regenerative dentistry: Current understanding and future directions.

BACKGROUND: Regenerative dentistry aims to enhance the structure and function of oral tissues and organs. Modern tissue engineering harnesses cell and gene-based therapies to advance traditional treatment approaches. Studies have demonstrated the potential of mesenchymal stem cells (MSCs) in regenerative dentistry, with some progressing to clinical trials. This review comprehensively examines animal studies that have utilized MSCs for various therapeutic applications. Additionally, it seeks to bridge the gap between related findings and the practical implementation of MSC therapies, offering insights into the challenges and translational aspects involved in transitioning from preclinical research to clinical applications. HIGHLIGHTS: To achieve this objective, we have focused on the protocols and achievements related to pulp-dentin, alveolar bone, and periodontal regeneration using dental-derived MSCs in both animal and clinical studies. Various types of MSCs, including dental-derived cells, bone-marrow stem cells, and umbilical cord stem cells, have been employed in root canals, periodontal defects, socket preservation, and sinus lift procedures. Results of such include significant hard tissue reconstruction, functional pulp regeneration, root elongation, periodontal ligament formation, and cementum deposition. However, cell-based treatments for tooth and periodontium regeneration are still in early stages. The increasing demand for stem cell therapies in personalized medicine underscores the need for scientists and responsible organizations to develop standardized treatment protocols that adhere to good manufacturing practices, ensuring high reproducibility, safety, and cost-efficiency. CONCLUSION: Cell therapy in regenerative dentistry represents a growing industry with substantial benefits and unique challenges as it strives to establish sustainable, long-term, and effective oral tissue regeneration solutions.

Blockchain technology: A potential tool for the management of pharma supply chain.

BACKGROUND: The pharma supply chain comprises various parties including distributors, manufacturers, raw material suppliers, regulators, pharmacies, hospitals, and patients. Due to the product's complexity and transaction flows, an efficient traceability system is needed in the pharma supply chain to identify the current and all previous product owners. Digitizing the track and trace process significantly improves regulatory oversight and guarantees product quality. A distributed platform for shared data that is immutable, trustworthy, accountable, and transparent in the pharmaceutical supply chain could be built using blockchain-based drug traceability. OBJECTIVE: This review aims to shed light on blockchain technology's significance and necessity for pharmaceutical supply chain management systems. METHOD: A comprehensive literature review was performed between January 2017 and September 2023. The search was conducted to elaborate on blockchain technology. Blockchain is a software-based technology that logs and records transactions using a block structure arranged chronologically. Cryptography technology links and secures these blocks on a peer-to-peer network. Blockchain is anticipated to transform the pharmaceutical supply chain by giving all participants access to a single, straightforward system that provides transparency, security, and oversight of the end-to-end delivery of goods. RESULT: In all, various literature data were included in this review. Using a supply chain powered by blockchain has many benefits. To begin with, it gives a thorough account of the entire procedure from start to finish. A single piece of software can manage the entire supply chain. Additionally, it increases communication between parties with permission. The enhanced security and traceability that blockchain offers is another important benefit. A blockchain system can track, trace, and recall products. CONCLUSION: Blockchain-based pharmaceutical supply chain management enables the tracking of medicinal drug transactions from raw materials suppliers to end consumers. The pharma blockchain has the potential to enhance the security, integrity, data provenance, and functionality of the supply chain due to its transparency, immutability, and auditability.

Crenolanib and Intensive Chemotherapy in Adults With Newly Diagnosed FLT3-Mutated AML.

PURPOSE: Crenolanib is a second-generation tyrosine kinase inhibitor with activity against FLT3-ITD- and TKD-mutant AML. We conducted a trial of crenolanib plus intensive chemotherapy in adults with newly diagnosed FLT3-mutant AML. METHODS: Eligible patients were 18 years and older. Induction chemotherapy consisted of cytarabine (100 mg/m2) continuous infusion on days 1-7 and anthracycline (daunorubicin 60-90 mg/m2 or idarubicin 12 mg/m2, once daily) on days 1-3 followed by consolidation with high-dose cytarabine (1-3 g/m2 twice daily on days 1, 3, 5) and/or allogeneic transplant. Crenolanib (100 mg thrice a day) was given from day 9 until 72 hours before the next cycle, after consolidation, and for 12 months after consolidation or transplant. RESULTS: Forty-four patients (median age, 57; range, 19-75 years) were enrolled. Thirty-six had FLT3-ITD, and 11 had FLT3-TKD mutations. European LeukemiaNet 2017 disease risk was favorable in 34%, intermediate in 30%, and adverse in 36%. The overall response rate was 86% (complete remission [CR], 77%; CR with incomplete count recovery [CRi], 9%): 90% in patients 60 years and younger and 80% in older patients. Measurable residual disease-negative CR/CRi rates were 89% and 45%, respectively. With a 45-month follow-up, median overall survival has not been reached and the median event-free survival was 44.7 months. Among younger patients, the estimated 3-year survival was 71.4% with 15% cumulative incidence of relapse. Treatment-related serious adverse events included febrile neutropenia, diarrhea, and nausea. The median time to platelets ≥100,000/µL and absolute neutrophil count ≥1,000/µL during induction was 29 and 32 days, respectively. No new FLT3-mutant clones were detected at relapse in patients completing consolidation. CONCLUSION: Crenolanib plus intensive chemotherapy in adults with newly diagnosed FLT3-mutant AML results in high rate of deep responses and long-term survival with acceptable toxicity. A randomized trial of crenolanib versus midostaurin plus chemotherapy in younger patients is ongoing.

Single tooth replacement utilizing implants in the esthetic zone: a case report.

Replacing a single tooth with an implant has become a common dental procedure; however, careful evaluation is necessary before placing one in the esthetic zone. Thorough diagnosis and planning - including the use of transposed diagnostic casts and cone beam computed tomography scans - can help dentists predict the final esthetic result prior to treatment, and help inform the patient of the potential result prior to performing any irreversible therapy. In the present case, the primary concern was the presurgical location of the facial free gingival margin (FGM) of the implant-supported crown, in relation to the adjacent teeth. Steps taken to correct the position of the facial FGM prior to implant placement led to a successful esthetic result.

A technique to create an interocclusal bite registration using in situ implant healing abutments.

Obtaining an accurate interocclusal record which relates the upper and lower jaws to one another is critical in the laboratory production of dental restorations. This may be particularly challenging when the configuration of missing teeth dictate that such records are dependent on the remaining mucosal tissues for support. This article presents a practical and time saving method of using implant healing abutments, located within an edentulous distal extension space, to serve as vertical stops for an interocclusal record.

Fabricating a mandibular implant supported overdenture with a suspended framework.

The introduction of implant-supported overdentures as a clinical alternative has improved the quality of life of the edentulous population. Implant-supported overdentures have diminished many of the problems associated with conventional dentures by providing improved retention, stability, function, esthetics and physical and emotional health. Greater support and stability of the implant borne prosthesis is associated with improved bite force and oral function for overdentures when compared to conventional complete dentures. An adequate amount of restorative space is required when fabricating implant-supported overdentures. This space must accommodate a denture base of sufficient dimensions, appropriately positioned denture teeth, and an implant attachment system. Insufficient space may lead to reduced structural integrity of the prosthesis and/or compromised oral function. Typically a mandibular removable prosthesis is more vulnerable to fracture due to its shape and overall dimensions. Incorporation of a metal framework, metal reinforcing mesh, or woven or fiberglass-impregnated mesh have been recommended to improve resistance to denture fracture during function. This article presents a method for fabricating a framework that is specifically and predictably suspended within the denture base in order to decrease fracture susceptibility of implant-supported overdentures.

An in vitro investigation to compare the surface roughness of auto glazed, reglazed and chair side polished surfaces of Ivoclar and Vita feldspathic porcelain.

The change in surface roughness after different surface finishing techniques has attracted the attention of several prosthodontists regarding wear of opposing teeth or restorative material and the strength; plaque retention and appearance of the restoration. However, there is considerable controversy concerning the best methods to achieve the smoothest and strongest porcelain restorations after chair side clinical adjustments. The purpose of this in vitro study was to compare the average surface roughness of a self-glazed surface, a chair side polished surface and a reglazed surface of ceramic. Two feldspathic porcelain, namely VITA VMK94 (Vita Zahnfabrik, Bad Sachingen, Germany) and IVOCLAR CLASSIC (Vivadent AG, FL-9494 Schaan, Liechtenstein) were selected to fabricate 20 specimens of each in the shape of shade guide tabs. A medium-grit diamond rotary cutting instrument was used to remove the glaze layer, and then the surface of half the specimens were re-glazed and the other half were polished using a well-defined sequence of polishing comprising of: Shofu porcelain polishing system, White gloss disc/polishing wheel, Silicone cone with diamond polishing paste and finally with small buff wheel with pumice slurry. The surface roughness (Ra) (µm) of the specimens was evaluated using a profilometer and scanning electron microscope. The data were statistically analyzed by using Student's t test. The results had shown that there is no statistically significant difference both quantitatively and qualitatively, between the surface roughness of reglazed and chair-side polished surface. In addition, both reglazed and chair-side polished surfaces are better than the autoglazed surface. Within all the groups, there is no significant difference between companies. Polishing an adjusted porcelain surface with the suggested sequence of polishing will lead to a finish similar to a re-glazed surface. Therefore chair-side polishing can be a good alternative to reglazing for finishing adjusted porcelain surface.

Non-linear dose response of DNA double strand breaks in response to chronic low dose radiation in individuals from high level natural radiation areas of Kerala coast.

BACKGROUND: The human population living in high level natural radiation areas (HLNRAs) of Kerala coast provide unique opportunities to study the biological effects of low dose and low dose rate ionizing radiation below 100 mGy. The level of radiation in this area varies from < 1.0 to 45 mGy/year. The areas with ≤ 1.50 mGy/year are considered as normal level natural radiation areas (NLNRA) and > 1.50 mGy/year, as high level natural radiation areas (HLNRA). The present study evaluated dose response relationship between DNA double strand breaks (DSBs) and background radiation dose in individuals residing in Kerala coast. Venous blood samples were collected from 200 individuals belonging to NLNRA (n = 50) and four dose groups of HLNRA; 1.51-5.0 mGy/year (n = 50), 5.01-10.0 mGy/year (n = 30), 10.01-15.0 mGy/year (n = 33), > 15.0 mGy/year (n = 37) with written informed consent. The mean dose of NLNRA and four HLNRA dose groups studied are 1.21 ± 0.21 (range: 0.57-1.49), 3.02 ± 0.95 (range: 1.57-4.93), 7.43 ± 1.48 (range: 5.01-9.75), 12.22 ± 1.47 (range: 10.21-14.99), 21.64 ± 6.28 (range: 15.26-39.88) mGy/year, respectively. DNA DSBs were quantified using γH2AX as a marker, where foci were counted per cell using fluorescence microscopy. RESULTS: Our results revealed that the frequency of γH2AX foci per cell was 0.090 ± 0.051 and 0.096 ± 0.051, respectively in NLNRA and HLNRA individuals, which were not significantly different (t198 = 0.33; P = 0.739). The frequency of γH2AX foci was observed to be 0.090 ± 0.051, 0.096 ± 0.051, 0.076 ± 0.036, 0.087 ± 0.042, 0.108 ± 0.046 per cell, respectively in different dose groups of ≤ 1.50, 1.51-5.0, 5.01-10.0, 10.01-15.0, > 15.0mGy/year (ANOVA, F4,195 = 2.18, P = 0.072) and suggested non-linearity in dose response. The frequency of γH2AX foci was observed to be 0.098 ± 0.042, 0.078 ± 0.037, 0.084 ± 0.042, 0.099 ± 0.058, 0.097 ± 0.06 and 0.114 ± 0.033 per cell in the age groups of ≤ 29, 30-34, 35-39, 40-44, 45-49 and ≥ 50 years, respectively (ANOVA, F5,194 = 2.17, P = 0.059), which suggested marginal influence of age on the baseline of DSBs. Personal habits such as smoking (No v/s Yes: 0.092 ± 0.047 v/s 0.093 ± 0.048, t198 = 0.13; P = 0.895) and drinking alcohol (No v/s Yes: 0.096 ± 0.052 v/s 0.091 ± 0.045, t198 = 0.62; P = 0.538) did not show any influence on DSBs in the population. CONCLUSION: The present study did not show any increase in DSBs in different dose groups of HLNRA compared to NLNRA, however, it suggested a non-linear dose response between DNA DSBs and chronic low dose radiation.

Determination of bioavailable arsenic threshold and validation of modeled permissible total arsenic in paddy soil using machine learning.

Minimizing arsenic intake from food consumption is a key aspect of the public health response in arsenic (As)-contaminated regions. In many of these regions, rice is the predominant staple food. Here, we present a validated maximum allowable concentration of total As in paddy soil and provide the first derivation of a maximum allowable soil concentration for bioavailable As. We have previously used meta-analysis to predict the maximum allowable total As in soil based on decision tree (DT) and logistic regression (LR) models. The models were defined using the maximum tolerable concentration (MTC) of As in rice grains as per the codex recommendation. In the present study, we validated these models using three test data sets derived from purposely collected field data. The DT model performed better than the LR in terms of accuracy and Matthews correlation coefficient (MCC). Therefore, the DT estimated maximum allowable total As in paddy soil of 14 mg kg-1 could confidently be used as an appropriate guideline value. We further used the purposely collected field data to predict the concentration of bioavailable As in the paddy soil with the help of random forest (RF), gradient boosting machine (GBM), and LR models. The category of grain As (MTC) was considered as the dependent variable; bioavailable As (BAs), total As (TAs), pH, organic carbon (OC), available phosphorus (AvP), and available iron (AvFe) were the predictor variables. LR performed better than RF and GBM in terms of accuracy, sensitivity, specificity, kappa, precision, log loss, F1score, and MCC. From the better-performing LR model, bioavailable As (BAs), TAs, AvFe, and OC were significant variables for grain As. From the partial dependence plots (PDP) and individual conditional expectation (ICE) of the LR model, 5.70 mg kg-1 was estimated to be the limit for BAs in soil.

Addressing the genetic/nongenetic duality in cancer with systems biology.

The dogma that cancer is a genetic disease is being questioned. Recent findings suggest that genetic/nongenetic duality is necessary for cancer progression. A think tank organized by the Shraman Foundation's Institute for Theoretical Biology compiled key challenges and opportunities that theoreticians, experimentalists, and clinicians can explore from a systems biology perspective to provide a better understanding of the disease as well as help discover new treatment options and therapeutic strategies.