NIR Spectroscopy as an Online PAT Tool for a Narrow Therapeutic Index Drug: Toward a Platform Approach Across Lab and Pilot Scales for Development of a Powder Blending Monitoring Method and Endpoint Determination.

An online near-infrared (NIR) spectroscopy platform system for real-time powder blending monitoring and blend endpoint determination was tested for a phenytoin sodium formulation. The study utilized robust experimental design and multiple sensors to investigate multivariate data acquisition, model development, and model scale-up from lab to manufacturing. The impact of the selection of various blend endpoint algorithms on predicted blend endpoint (i.e., mixing time) was explored. Spectral data collected at two process scales using two NIR spectrometers was incorporated in a single (global) calibration model. Unique endpoints were obtained with different algorithms based on standard deviation, average, and distributions of concentration prediction for major components of the formulation. Control over phenytoin sodium's distribution was considered critical due to its narrow therapeutic index nature. It was found that algorithms sensitive to deviation from target concentration offered the simplest interpretation and consistent trends. In contrast, algorithms sensitive to global homogeneity of active and excipients yielded the longest mixing time to achieve blending endpoint. However, they were potentially more sensitive to subtle uniformity variations. Qualitative algorithms using principal component analysis (PCA) of spectral data yielded the prediction of shortest mixing time for blending endpoint. The hybrid approach of combining NIR data from different scales presents several advantages. It enables simplifying the chemometrics model building process and reduces the cost of model building compared to the approach of using data solely from commercial scale. Success of such a hybrid approach depends on the spectroscopic variability captured at different scales and their relative contributions in the final NIR model.

An In Vitro Study to Compare the Release of Fluoride from Glass Ionomer Cement (Fuji IX) and Zirconomer.

Mercury toxicity from amalgam dental fillings and their potential for creating problems in the environment and for human health have prompted the development of new restorative materials. The leading alternatives among these are glass ionomer cements. According to current understanding, restorative materials that slowly release fluoride exert a local cariostatic effect. For this purpose, glass ionomer cements have desirable properties in that they help prevent recurrence of caries by releasing fluoride over a long period. Thus, they function in accord with the major cariostatic mechanism of fluoride, which is believed to be its action to promote remineralization and to influence the morphology of teeth by reducing enamel solubility and by suppressing oral cariogenic bacteria. Although the minimum local concentration of fluoride release required to inhibit demineralization has not been determined, it is reported that the cariostatic ability of fluoride releasing restorative materials is significant. Zirconomer defines a new class of restorative that promises the strength and durability of amalgam with the protective benefits of glass ionomer while completely eliminating the hazards of mercury. The inclusion of specially micronized zirconia fillers in the glass component of zirconomer reinforces the structural integrity of the restoration and imparts superior mechanical properties for the restoration of load-bearing permanent teeth. Combination of outstanding strength, durability, and sustained fluoride protection deems it ideal for multiple applications. The aim of the present study was to determine the fluoride release from glass ionomer cements and compare it with new material zirconomer. Materials and methods: Sample preparation: Tablets of glass-ionomer cements and zirconomer were prepared. A dental floss was incorporated into the tablets during fabrication to allow suspension into the test medium. Each disk specimen was immersed in airtight polyethylene bottle containing 20 mL of deionized water and incubated at 37°C and stored for 24 hours. Determination of fluoride ion release: Fluoride ion measurement was performed after 6 hours, 24 hours, 48 hours, 7 days, and 14 days under normal atmospheric conditions by fluoride ion selective electrode connected to an ion selective electrode meter. Result and conclusion: Both the material tested in the study had the ability to release fluoride but higher fluoride release was observed by zirconomer as compared to GIC at all time intervals. Clinical significance: From a clinical point of view, both the restorative materials release fluoride at all time intervals; however, addition of zirconia particles in zirconomer increases its strength and provides superior mechanical properties. Therefore, due to the combination of both good structural integrity and fluoride releasing properties, zirconomer can be used for restoration of load bearing teeth. How to cite this article: Kukreja R, Singla S, Bhadoria N, et al. An In Vitro Study to Compare the Release of Fluoride from Glass Ionomer Cement (Fuji IX) and Zirconomer. Int J Clin Pediatr Dent 2022;15(1):35-37.

Development and Scale-Up of Diversion Strategy for Twin Screw Granulation in Continuous Manufacturing.

Successful implementation of Continuous Manufacturing technology requires real time product quality monitoring that can result into rejection strategies for material manufactured outside process control limits. In a twin screw granulation process, parameters like water content, powder feed rate, and granulator screw speed can influence granule quality. Deviations in any of these parameters from the set-point may affect granule quality. Having a sound diversion strategy in place can help divert these implicated granules to waste. Residence time distribution experiments were conducted on a 16-mm Thermo Fisher twin screw granulator (TSG) for a range of process parameters, and the data was modelled to predict the needed diversion time as a function of process parameters. Scale-up from the 16-mm to 24-mm granulator was evaluated and data was found to scale based on mass per unit volume of granulator (channel fill), thus enabling 16-mm data to scale to 24-mm. The diversion strategy proposed is based on utilizing a wash out curve derived from residence time distribution to quantify the maximum concentration of implicated material that could be present in the next downstream unit operation(s) (e.g. a fluid bed dryer) and ensuring it is less than a suitable threshold to prevent product quality impact.

Ectodermal dysplasia - A rare case report.

Ectodermal dysplasia (ED) is a rare genetic disease caused by developmental disturbances of embryonic ectoderm derived tissues, organs, and other accessory appendages. The congenital missing of teeth is usually bilateral. Anodontia or hypodontia may be associated with other ectodermal disturbances, such as anhidrosis, asteatosis, hypotrichosis, and salivary glands defects. One such case report of ED is demonstrated here.

Effect of casein phosphopeptide-amorphous calcium phosphate as a remineralizing agent - An In Vivo study.

INTRODUCTION: Demineralization and remineralization have a crucial impact on the hardness and strength of teeth. Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) Trident white chewing gum has anticariogenic property and also stimulates saliva, which buffers the oral cavity and promotes remineralization. Trident sugar-free gum, therefore, is an excellent delivery vehicle for promoting enamel remineralization. AIMS AND OBJECTIVES: The aim of this study is to show that CPP-ACP-containing chewing gum would increase the level of calcium concentration of saliva, thereby supplying calcium and phosphorus to whole dentition for a prolonged period and aid in remineralization of tooth surfaces. MATERIALS AND METHODS: An in vivo nonrandomized clinical trial study was carried among 60 children. Unstimulated saliva from each 60 selected participants was collected. Then each participant was given two pellets of chewing gum containing CPP-ACP and asked to chew for a period of 20 min, after which saliva samples were again collected from each participant. The study was carried out for 15 days, and at three intervals, calcium and phosphorus levels were assessed using affiliated reagent kits and spectrophotometer. RESULTS: Significant difference was found in the calcium and phosphorus concentration of saliva before and after chewing CPP-ACP-containing chewing gum. When post calcium and phosphate levels were analyzed among different time intervals, a highly statistically significant difference was observed (P = 0.000). CONCLUSION: Clinical trial study shows that chewing sugar-free gum containing CPP-ACP can be regarded as an additional caries prevention tool.

A "Large-N" Content Uniformity Process Analytical Technology (PAT) Method for Phenytoin Sodium Tablets.

Accurate assessment of tablet content uniformity is critical for narrow therapeutic index drugs such as phenytoin sodium. This work presents a near-infrared (NIR)-based analytical method for rapid prediction of content uniformity based on a large number of phenytoin sodium formulation tablets. Calibration tablets were generated through an integrated experimental design by varying formulation and process parameters, and scale of manufacturing. A partial least squares model for individual tablet content was developed based on tablet NIR spectra. The tablet content was obtained from a modified United States Pharmacopeia phenytoin sodium high-performance liquid chromatography assay method. The partial least squares model with 4 latent variables explained 92% of the composition variability and yielded a root mean square error of prediction of 0.48% w/w. The resultant NIR model successfully assayed the composition of tablets manufactured at the pilot scale. For one such batch, bootstrapping was applied to calculate the confidence intervals on the mean, acceptance value, and relative SD for different sample sizes, n = 10, 30, and 100. As the bootstrap sample size increased, the confidence interval on the mean, acceptance value, and relative SD became narrower and symmetric. Such a 'large N' NIR-based process analytical technology method can increase reliability of quality assessments in solid dosage manufacturing.

Depletion of Key Meiotic Genes and Transcriptome-Wide Abiotic Stress Reprogramming Mark Early Preparatory Events Ahead of Apomeiotic Transition.

Molecular dissection of apomixis - an asexual reproductive mode - is anticipated to solve the enigma of loss of meiotic sex, and to help fixing elite agronomic traits. The Brassicaceae genus Boechera comprises of both sexual and apomictic species, permitting comparative analyses of meiotic circumvention (apomeiosis) and parthenogenesis. Whereas previous studies reported local transcriptome changes during these events, it remained unclear whether global changes associated with hybridization, polyploidy and environmental adaptation that arose during evolution of Boechera might serve as (epi)genetic regulators of early development prior apomictic initiation. To identify these signatures during vegetative stages, we compared seedling RNA-seq transcriptomes of an obligate triploid apomict and a diploid sexual, both isolated from a drought-prone habitat. Uncovered were several genes differentially expressed between sexual and apomictic seedlings, including homologs of meiotic genes ASYNAPTIC 1 (ASY1) and MULTIPOLAR SPINDLE 1 (MPS1) that were down-regulated in apomicts. An intriguing class of apomict-specific deregulated genes included several NAC transcription factors, homologs of which are known to be transcriptionally reprogrammed during abiotic stress in other plants. Deregulation of both meiotic and stress-response genes during seedling stages might possibly be important in preparation for meiotic circumvention, as similar transcriptional alteration was discernible in apomeiotic floral buds too. Furthermore, we noted that the apomict showed better tolerance to osmotic stress in vitro than the sexual, in conjunction with significant upregulation of a subset of NAC genes. In support of the current model that DNA methylation epigenetically regulates stress, ploidy, hybridization and apomixis, we noted that ASY1, MPS1 and NAC019 homologs were deregulated in Boechera seedlings upon DNA demethylation, and ASY1 in particular seems to be repressed by global DNA methylation exclusively in the apomicts. Variability in stress and transcriptional response in a diploid apomict, which is geographically distinct from the triploid apomict, pinpoints both common and independent features of apomixis evolution. Our study provides a molecular frame-work to investigate how the adaptive traits associated with the evolutionary history of apomicts co-adapted with meiotic gene deregulation at early developmental stage, in order to predate meiotic recombination, which otherwise is thought to be favorable in stress and low-fitness conditions.

Enabling real time release testing by NIR prediction of dissolution of tablets made by continuous direct compression (CDC).

A method for predicting dissolution profiles of directly compressed tablets for a fixed sustained release formulation manufactured in a continuous direct compaction (CDC) system is presented. The methodology enables real-time release testing (RTRt). Tablets were made at a target drug concentration of 9% Acetaminophen, containing 90% lactose and 1% Magnesium Stearate, and at a target compression force of 24kN. A model for predicting dissolution profiles was developed using a 3(4-1) fractional factorial experimental design built around this targeted condition. Four variables were included: API concentration (low, medium, high), blender speed (150rpm, 200rpm, 250rpm), feed frame speed (20rpm, 25rpm, 30rpm), compaction force (8KN, 16KN, 24KN). The tablets thus obtained were scanned at-line in transmission mode using Near IR spectroscopy. The dissolution profiles were described using two approaches, a model-independent "shape and level" method, and a model-dependent approach based on Weibull's model. Multivariate regression was built between the NIR scores as the predictor variables and the dissolution profile parameters as the response. The model successfully predicted the dissolution profiles of the individual tablets (similarity factor, f2 ∼72) manufactured at the targeted set point. This is a first ever published manuscript addressing RTRt for dissolution prediction in continuous manufacturing, a novel and state of art technique for tablet manufacturing.

Effect of Shear Applied During a Pharmaceutical Process on Near Infrared Spectra.

This study describes changes observed in the near-infrared (NIR) diffuse reflectance (DR) spectra of pharmaceutical tablets after these tablets were subjected to different levels of strain (exposure to shear) during the mixing process. Powder shearing is important in the mixing of powders that are cohesive. Shear stress is created in a system by moving one surface over another causing displacements in the direction of the moving surface and is part of the mixing dynamics of particulates in many industries including the pharmaceutical industry. In continuous mixing, shear strain is developed within the process when powder particles are in constant movement and can affect the quality attributes of the final product such as dissolution. These changes in the NIR spectra could affect results obtained from NIR calibration models. The aim of the study was to understand changes in the NIR diffuse reflectance spectra that can be associated with different levels of strain developed during blend shearing of laboratory samples. Shear was applied using a Couette cell and tablets were produced using a tablet press emulator. Tablets with different shear levels were measured using NIR spectroscopy in the diffuse reflectance mode. The NIR spectra were baseline corrected to maintain the scattering effect associated with the physical properties of the tablet surface. Principal component analysis was used to establish the principal sources of variation within the samples. The angular dependence of elastic light scattering shows that the shear treatment reduces the size of particles and produces their uniform and highly isotropic distribution. Tablet compaction further reduces the diffuse component of scattering due to realignment of particles.

Prediction of dissolution profiles by non-destructive near infrared spectroscopy in tablets subjected to different levels of strain.

This study describes how the strain on formulation components affects dissolution and how near infrared spectroscopy can be used to predict dissolution. Strain (exposure to shear stress) applied during powder mixing affects the interaction between formulation components. Particles experience shear strain when they move relative to each other in a process affecting the properties of the final product. This stress affects the dissolution of oral solid dosages forms. However, dissolution testing destroys the entire tablet, making it impossible to further evaluate tablet properties when an out of specification result is obtained. Thus, a nondestructive technique such as near infrared spectroscopy is desirable to predict dissolution. The aim of this study was to predict dissolution on tablets with different levels of strain (shear) using near infrared spectroscopy in combination with multivariate data analysis. Shear was induced using a modified Couette cell on the powder mixture and tablets from these mixtures were produced using a tablet press emulator. Tablets produced with different strain levels were measured using near infrared spectroscopy. Spectra were obtained in diffuse reflectance mode and pretreated with baseline correction to maintain the physical and chemical information of the tablets. Dissolution profiles were obtained using USP Apparatus 2 as a reference method. Principal component analysis was used to study the sources of variation in the spectra obtained. Partial least squares 2 was used to predict dissolution on tablets with different levels of strain.

Ameliorating effect of S-2(ω-aminoalkylamino) alkylaryl sulfide (DRDE-07) on sulfur mustard analogue, 2-chloroethyl ethyl sulfide-induced oxidative stress and inflammation.

Sulfur mustard (SM; 2,2'-dichloro diethyl sulfide), an alkylating chemical warfare agent, poses a major threat in both military conflict and chemical terrorism situations. 2-chloroethyl ethyl sulfide (CEES) is a monofunctional analogue of SM, frequently used in laboratory settings, therefore increasing chances of its exposure. S-2(ω-aminoalkylamino) alkylaryl sulfide (DRDE-07) is an analogue of amifostine reported to have protective effects against SM but its effect on CEES is largely unexplored. Therefore, this study was planned to explore the effects of DRDE-07 against CEES-induced toxicity. 0.75 LD50 (1068 mg/kg) of CEES was exposed percutaneously in the presence or absence of DRDE-07 (249 mg/kg p.o.) which is given prophylactically (before 30 minute) to male mice. Animals were sacrificed on 24 h, 7th day and 14th day of CEES exposure, and tissues were collected to study oxidative stress and inflammatory markers. CEES exposure depleted intracellular GSH level and activities of GSH-linked enzymes (GR, GPx and GST) which play a major role in GSH metabolism. CEES exposure augmented lipid peroxidation indicating severe oxidative stress. It also initiated inflammation causing an increase in proinflammatory (IL1-α, IL1-ß, IL-6, TNF-α and IFN-ϒ) and corresponding decrease in anti-inflammatory cytokines (IL-4 and IL-10). This was also accompanied by neutrophils infiltration indicated by higher than normal myeloperoxidase (MPO) levels. DRDE-07 efficiently reduced the oxidative stress and also facilitated to resolve inflammatory alterations. This study thus evaluated the beneficial role of DRDE-07 in ameliorating the deleterious effects of CEES and can be potentially used against SM/CEES poisoning.

Cholesterol assimilation and biotransformation by Lactobacillus helveticus.

Lactobacillus helveticus, grown at 37°C in MRS medium supplemented with 3 mM cholesterol, assimilated all the cholesterol in 42 h having 68 U mg(-1) of intracellular cholesterol oxidase activity. The strain transformed 1 g cholesterol to 0.05 g of androsta-1, 4-diene-3, 17-dione and 0.04 g of androst-4-ene-3, 17 dione within 48 h at 37°C with extracellular cholesterol oxidase activity at 12 U mg(-1) and intracellular oxidase at 0.5 U mg(-1).

Effect of Plant Extracts Formulated in Different Ointment Bases on MDR Strains.

Extracts of Aloe vera whole plant, Eucalyptus globulus leaves, Ficus infectoria bark, Ficus religiosa bark and Piper betel leaves were studied for antibacterial activity on resistant and sensitive strains, isolated from skin and soft tissue infections. A combination of hot alcoholic extracts of Ficus infectoria, Ficus religiosa and Piper betel were found to be more effective against all the isolates. The combined extract was formulated in different ointment bases such as polyethylene glycol, gelatin, sodium alginate, carbopol, cream base and honey. These were then evaluated to find a suitable base for preparation of an ointment. In vitro study of the release of antimicrobials and kill-time studies of the herbal ointments was carried out against multi-drug resistant isolate of Pseudomonas. The ointment showed bactericidal activity within 2 h against the resistant strain of Pseudomonas spp.