Identification of allosteric hotspots regulating the ribosomal RNA binding by antibiotic resistance-conferring Erm methyltransferases.

Antibiotic resistance via epigenetic methylation of ribosomal RNA is one of the most prevalent strategies adopted by multidrug resistant pathogens. The erythromycin-resistance methyltransferase (Erm) methylates rRNA at the conserved A2058 position and imparts resistance to macrolides such as erythromycin. However, the precise mechanism adopted by Erm methyltransferases for locating the target base within a complicated rRNA scaffold remains unclear. Here, we show that a conserved RNA architecture, including specific bulge sites, present more than 15 Å from the reaction center, is key to methylation at the pathogenic site. Using a set of RNA sequences site-specifically labeled by fluorescent nucleotide surrogates, we show that base flipping is a prerequisite for effective methylation and that distal bases assist in the recognition and flipping at the reaction center. The Erm-RNA complex model revealed that intrinsically flipped-out bases in the RNA serve as a putative anchor point for the Erm. Molecular dynamic simulation studies demonstrated the RNA undergoes a substantial change in conformation to facilitate an effective protein-rRNA handshake. This study highlights the importance of unique architectural features exploited by RNA to impart fidelity to RNA methyltransferases via enabling allosteric crosstalk. Moreover, the distal trigger sites identified here serve as attractive hotspots for the development of combination drug therapy aimed at reversing resistance.

Comparison of dimensional accuracy of elastomeric impression materials using 3D laser scanner.

Background: The dimensional accuracy of elastomeric impression materials has been evaluated by different methods but their reliability is still questionable. The aim of this study was to evaluate the dimensional accuracy of elastomeric impression material using 3D laser scanner. Method: In the present study, a metal die with its custom tray were designed. Using this die and tray, 10 impressions each were made from addition silicone (Aquasil LV; Dentsply), condensation silicone (Speedex coltene, Whaledent) and polyether (3M; ESPE). All the impressions were poured with Type IV die stone and total of 30 die replicas were obtained. These were scanned with a Picza 3D laser scanner (LPX 600, Roland,California) and the difference between the stone model was calculated by determining its volumetric changes using CAD-CAM pero version 2.0. One way analysis of variance (ANOVA) was used to compare the groups, whereas significance of mean difference between the groups was done by Tukey HSD. Results: All the three groups showed mean decrease indicating a dimensional shrinkage from the master die. Mean percentage dimensional change in condensation silicone was maximum (-319.02 ±15.50) followed by polyether (-122.59 ± 0.64) and least in addition silicone (-23.83 ± 0.43). All the results were statistically significant (p<0.001). Conclusion: Picza 3D laser scanner can precisely measure the volumetric changes in all the three elastomeric impression materials.

Incidence of Obstructive Sleep Apnea in Elderly Edentulous Patients and the Possible Correlation of Serum Serotonin and Apnea-Hypopnea Index.

PURPOSE: To estimate the incidence of obstructive sleep apnea (OSA) in elderly edentulous patients (aged 60-65 years) and investigate a correlation of serum serotonin levels with the apnea-hypopnea index (AHI), respiratory effort-related arousal (RERA), and respiratory disturbance index (RDI). MATERIALS AND METHODS: 381 elderly completely edentulous patients (307 male, 74 female) aged 60 to 65 years with a history of edentulism of 12 to 15 months, seeking oral rehabilitation at the prosthodontic clinic at Saraswati Dental College & Hospital, Lucknow, India, between January 2014 and January 2016 were enrolled for the present study. After application of the inclusion and exclusion criteria of this study, 183 patients (162 male, 21 female) who were found susceptible, were subjected to the BERLIN questionnaire and Epworth Sleepiness Scale (ESS) to assess sleep disordered breathing (SDB) and then put through all-night polysomnography (PSG). On the basis of AHI, RERA, and RDI scores, 156 patients (143 male, 13 female) who tested positive for OSA were classified according to its intensity. All 156 patients underwent body-mass index (BMI) estimation, cephalometry, and intraoral examination for skeletal and soft tissue profile record. Serum serotonin was estimated from whole blood samples for the 156 OSA and the 27 normal patients. The 156 (147 nonobese, 9 obese) OSA-positive patients were provided with complete dentures and were trained to use the same as a modified mandibular advancement device (MAD) during sleep at night. These patients were kept on a quarterly follow-up for 9 months. Data collected was subjected to statistical analysis, and inferences drawn. RESULTS: The incidence of OSA in elderly edentulous subjects was found to be 32.03% in males and 8.91% in females. A mere 9 out of 156 (5.76%) elderly edentulous OSA patients were found to be obese (Class I) on the basis of BMI estimation. Cephalometry of the patients showed that they had a skeletal class I maxillomandibular relationship. AHI scores of nonobese patients revealed that most of the patients had moderate OSA, followed by mild OSA and severe OSA. Serum serotonin levels ranged from 53 to 83 ng/dL. AHI score of the 9 obese patients were in the moderate to severe range, and their serum serotonin levels were 60 to 70 ng/dL. A correlation between severity of OSA and serum serotonin level was validated in this study. CONCLUSION: OSA was found to be prevalent in edentulous subjects due to pharyngeal collapse and decreased neuromuscular control. An inverse relationship of serum serotonin levels and AHI scores was established.

Obstructive Sleep Apnea and Neurocognitive Dysfunction in Edentulous Patients.

PURPOSE: To record the incidence of cognitive dysfunction in edentulous patients suffering from obstructive sleep apnea (OSA) and establish a plausible hypothesis to explain the correlation of cognitive dysfunction and OSA. MATERIALS AND METHODS: In this study, 315 edentulous patients (aged 60 to 65 years) visiting the outpatient department at Saraswati Dental College, Lucknow were recruited from January 2013 to October 2015. Prosthodontic Diagnostic Index (PDI) classification was used to assess the intraoral condition to relate it with the span of edentulousness. The BERLIN questionnaire and Epworth Sleepiness Scales were used to diagnose sleep-disordered breathing, following which the patients were put through all-night polysomnography. The apnea-hypopnea index (AHI) scores were derived. Mild and moderate OSA patients were classified into mild, moderate, and severe cognitive dysfunction based on SGRQ-C and SCD. Data were tabulated according to a new classification (Cognitive Dysfunction of Dental Sleep Medicine Patients [CDDSMP] Classification) designed specifically for this study. Data were analyzed using SPSS v15.0. Scores were tabulated as mean ± SD and median [IQR] values. Change from baseline was analyzed using Wilcoxon signed rank test. RESULTS: Mean scores at different time intervals were 3.03 ± 1.76 (3 months), 2.98 ± 1.80 (6 months), and 2.81 ± 1.84 (9 months). The median [IQR] values of scores at all time intervals except 9 months were 3 [1 to 5]. At 9 months, median [IQR] was 2 [1 to 5]. A significant change in scores was observed in the 3-month interval (p ≤ 0.001). CONCLUSIONS: The severity of OSA and neurocognitive dysfunction could be directly related to the PDI classification and the span of edentulousness of the patient and modified mandibular advancement device treatment significantly improved the patients' condition, which was reflective from 3 months post-intervention itself.

Preparation, characterization, and in vivo evaluation of nano formulations of ferulic acid in diabetic wound healing.

Diabetes mellitus is most common disorder characterize by hyperglycemia. Chronic hyperglycemia may lead to over production of free radicals thereby results in oxidative stress which impaired healing of wounds. Ferulic acid (FA) has been shown to have antidiabetic and antioxidant properties. The aim of the present study was to develop Ferulic acid nanoparticles and to study its hypoglycemic and wound healing activities. Ferulic acid-poly(lactic-co-glycolic acid) (FA-PLGA) nanoparticles were prepared by nano precipitation method. The prepared FA-PLGA nanoparticles had an average size of 240 nm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis showed the prepared FA-PLGA nanoparticles were spherical in shape. Drug encapsulation assay showed that 88.49% FA was encapsulated in PLGA. Carbopol 980 was used to formulate FA-PLGA nanoparticles loaded hydrogel. FA-loaded polymeric nanoparticles dispersion (oral administration) and FA-loaded polymeric nanoparticles based hydrogel (topical administration) treated wounds were found to epithelize faster as compared with diabetic wound control group. The hydroxyproline content increased significantly when compared with diabetic wound control. Therefore, the results indicate that FA significantly promotes wound healing in diabetic rats.

Effect of Firing Temperature at the Porcelain-Metal Alloy Interface in Porcelain-Fused-to-Metal Restorations. A SEM/EDS Study.

PURPOSE: To probe in greater detail the changes at the ceramometal interface induced by heat energy absorption, using energy diffraction X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) and correlate these changes with the shear bond strength of porcelain to nickel chromium alloy. MATERIALS AND METHODS: Seventy-five strips of nickel-chromium alloy (20 mm long, 5 mm wide, 3 mm thick) were prepared and layered with porcelain, conforming to ANSI/ADA specification no. 38 (for Metal-Ceramic Dental Restorative Systems: 2010). These test specimens were divided equally into three groups. Specimens of each group (25) were fired to a specific temperature range, that is 700°C, 900°C, and 960°C. SEM and EDS were performed on all specimens, at the metal alloy/ceramic interface. Bonding of the ceramic layer to the metal alloy was evaluated by a shear bond strength test as per ANSI/ADA specification no. 38. The data were recorded and analyzed using one-way ANOVA and post hoc Tukey HSD test. RESULTS: SEM images of the porcelain/metal alloy interface revealed roughness of the metal alloy surface adjacent to the ceramic layer. EDS study revealed that an oxygen depletion zone was formed at the interface region, facilitating the formation of intermetallic compounds. The mean shear bond strength showed an upward trend until 900°C and decreased thereafter. CONCLUSION: Formation of intermetallic compounds at the interface, in the presence of an oxygen depletion zone, was the prime factor in bonding of porcelain to metal alloy. This provides a new concept of ceramometal bonding.

Effect of Different Firing Temperatures on Structural Changes in Porcelain.

PURPOSE: To study the structural changes occurring in the dental porcelain mass fired at various firing temperatures using scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectroscopy. Also, additional tests, namely compressive strength, abrasion resistance analysis, and the amount of oxides released, were conducted at different firing temperatures. MATERIALS AND METHODS: Six groups (40 specimens in each group) of porcelain mass were prepared. The dimensions and weight of all the specimens were kept constant. The specimens were then heat treated at different firing temperatures (660°C, 760°C, 860°C, 900°C, 960°C, 990°C). Half of the specimens of each group were subjected to a compressive strength test on a universal testing machine and then finely ground using an electrochemical grinder to prepare for XRD analysis. The other half of the specimens was weighed to analyze the amount of oxides released after each firing cycle. Following this, the specimens underwent an abrasion resistance test on a Nanovea Tribometer. The unaltered surface was scanned using SEM. The data (numerical and graphical) for all the tests were recorded and analyzed using one-way ANOVA and post hoc Tukey test. RESULTS: The specimens fired at 900°C exhibited superior compressive strength and abrasion resistance. The quantity of oxides released by the specimens fired at 900°C was the least compared to specimens heat treated at the other firing temperatures. XRD analysis proved that the oxide released by the porcelain mass was calcium aluminum chromium oxide. Also, the fewer peaks obtained in the XRD graphs of specimens fired at 900°C signified lesser porosities in the porcelain specimens. SEM analysis depicted a homogeneous mass of porcelain at 900°C. CONCLUSION: All the above findings validate the objective of studying the physical and internal structural changes of dental porcelain when subjected to an increasing firing temperature gradient. The specimens fired at 900°C exhibited superior strength and abrasion resistance. SEM analysis depicted a homogeneous mass of dental porcelain, implying that firing was complete at 900°C.

Lifestyle and Occupational Stress: A Potential Risk Factor for Obstructive Sleep Apnea in Nonobese Male Subjects.

PURPOSE: To record the incidence of obstructive sleep apnea (OSA) in nonobese male subjects and investigate the coexistence of lifestyle stress, sleep deprivation, and upper airway inflammation. MATERIALS AND METHODS: 552 patients were assessed during a survey of banks, government and corporate offices, recruitment agencies, and schools between January 2012 and January 2016. After applying the inclusion and exclusion criteria designed for this study, the number of patients tapered down to 120 patients who underwent diagnostic tests, viz. polysomnography, chemiluminiscence immunoassay, nephelometry, and upper airway endoscopy. This revealed the presence of OSA coexistent with elevated serum cortisol, C-reactive protein (CRP), and upper airway inflammation. RESULTS: Polysomnography showed that 57 of 120 patients suffered from OSA. Objective evaluation of these patients exposed an undercurrent of lifestyle stress in 39 patients. CRP and serum cortisol were found to be significantly high (1.60 ± 0.52 and 7.20 ± 0.76 µg/dL, respectively) in 30 patients. Endoscopy revealed 18 patients with moderate, 7 with severe, and 5 with no upper airway inflammation. CONCLUSION: The results of this study demonstrated that OSA was found to be prevalent in the cohort of nonobese male patients studied. Coexistence of lifestyle stress, sleep deprivation, and upper airway inflammation was revealed.

The long intergenic non-coding RNA LINC01140 modulates gastric cancer phenotypes and cancer cell lines aggressiveness.

BACKGROUND: Long-intergenic non-protein coding gene 01140 (LINC01140) a long non-coding RNA is highly expressed in various cancers. However, its biological functions in gastric cancer progression is still unknown. METHOD: To elucidate LINC01140 function, 70 GC tumor samples and 30 normal gastric tissues were collected. LINC01140 expression level were determined by qRT-PCR analysis and correlated with different clinico-pathological parameters. Then we tried to see the impact of LINC01140 on gastric cell line aggressiveness by knocking down the target gene and performing cell viability assay, migration assay and invasive capacity of the cell lines along with immunoblotting to check several protein levels. RESULT: LINC01140 RNA is found to be positively correlated with FGF9 and significantly up regulated in GC tissues. LINC01140 knockdown inhibited the viability, migratory capacity and invasive capacity of AGS cells. LINC01140 targets miR-140-5p, while miR-140-5p targeted FGF9 to form lncRNA-miRNA-mRNA axis. The affect of miR-140-5p inhibition on gastric cancer cell aggressiveness were opposite to those of LINC01140 or FGF9 knockdown. Additionally, inhibition partially reversed the effects of LINC01140 knockdown on FGF9 protein levels, gastric cancer cell phenotypes. CONCLUSION: LINC01140, miR-140-5p and FGF9 form a lncRNA-miRNA-mRNA axis that modulates the gastric cancer phenotypes and in turn affects gastric cancer cell aggressiveness.

Exploring Therapeutic Digestive Enzyme Landscape in India: Current Evidence, Profit Motives, Regulations, and Future Perspectives.

This analysis critically examines the profit-driven marketing of digestive enzymes as over-the-counter (OTC) supplements in the context of India, expressing ethical concerns regarding pharmaceutical companies prioritizing financial gain over genuine public health needs within the lucrative OTC supplement market. The review delves into various enzymes, their mechanisms of action, uses, adverse drug reactions, and provides evidence from various studies. The research method involves the exploration of profit-driven strategies employed by pharmaceutical companies, addressing regulatory challenges, investigating the gap between dietary supplements and pharmaceutical drugs, and emphasizing the impact of direct-to-consumer advertising on self-diagnosis and overuse. Additionally, the study reviews various e-pharmacy platforms in India, assessing formulations and pricing. Key findings highlight the diverse formulations on these platforms, exposing insights into cost variations and indicating a regulatory gap that necessitates a comprehensive re-evaluation by Indian and international authorities. The analysis emphasizes the influence of direct-to-consumer advertising on behavior and potential health risks, raising ethical concerns about oversimplified health claims that overlook the necessity for individualized treatment plans. In conclusion, the study underscores the ethical complexity of prioritizing profit over public health and advocates for regulatory re-evaluation, exploring broader implications such as cultural influences and alternative therapies. The evolving landscape, featuring plant-based and microbe-derived alternatives, is presented as transformative, particularly in conditions like celiac disease.

The Role of Sodium-Glucose Co-transporter 2 Inhibitors in Patients With Hypomagnesemia: A Systematic Review.

Sodium-glucose co-transporter 2 (SGLT2) inhibitors, initially developed for glycemic control in type 2 diabetes, have demonstrated benefits in reducing heart failure hospitalizations, slowing chronic kidney disease, and decreasing major cardiovascular events. Recent studies have shown that SGLT2 inhibitors can elevate serum magnesium levels in patients with type 2 diabetes, suggesting potential benefits in managing refractory hypomagnesemia. This systematic review analyzed relevant case reports, observational studies, and randomized controlled trials (RCTs) to investigate the association between SGLT2 inhibitors and hypomagnesemia. The review adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and study quality was assessed using the CAse REport (CARE) guidelines. It encompassed four case reports, one retrospective observational study, one post-hoc analysis of 10 RCTs, and one meta-analysis of 18 RCTs, with a total study population of 19,767 patients. The meta-analysis revealed that SGLT2 inhibitors significantly increased serum magnesium levels in patients with type 2 diabetes, with a linear dose-dependent increase noted particularly for canagliflozin. Additionally, the case reports and other studies suggested that SGLT2 inhibitors could exert extraglycemic effects, potentially enhancing magnesium balance beyond their impact on urinary magnesium excretion. This systematic review underscores the effectiveness of SGLT2 inhibitors in addressing refractory hypomagnesemia linked with urinary magnesium wasting. It also suggests promising avenues for the application of these drugs in diverse patient populations.

Color changing bioadhesive barrier for peripherally inserted central catheters.

Bacteria migration at catheter insertion sites presents a serious complication (bacteraemia) with high mortality rates. One strategy to mediate bacteraemia is a physical barrier at the skin-catheter interface. Herein a colorimetric biosensor adhesive (CathoGlu) is designed and evaluated for both colorimetric detection of bacterial infection and application as a bacteria barrier. The design intent combines viscous, hydrophobic bioadhesive with an organic pH indicator (bromothymol blue). Visual observation can then distinguish healthy skin at pH = ∼5 from an infected catheter insertion site at pH = ∼8. The liquid-to-biorubber transition of CathoGlu formulation occurs via a brief exposure to UVA penlight, providing an elastic barrier to the skin flora. Leachates from CathoGlu demonstrate no genotoxic and skin sensitization effect, assessed by OECD-recommended in vitro and in chemico assays. The CathoGlu formulation was found non-inferior against clinically approved 2-octyl-cyanoacrylate (Dermabond™), and adhesive tape (Micropore™) within an in vivo porcine model. CathoGlu skin adhesive provides new opportunities to prevent sepsis in challenging clinical situations.

Bacterial cellulose adhesive patches designed for soft mucosal interfaces.

The wet environment in the oral cavity is challenging for topical disease management approaches. The compromised material properties leading to weak adhesion and short retention (<8 h) in such environment result in frequent reapplication of the therapeutics. Composites of bacterial cellulose (BC) and carbene-based bioadhesives attempt to address these shortcomings. Previous designs comprised of aqueous formulations. The current design, for the first time, presents dry, shelf-stable cellulose patches for convenient ready-to-use application. The dry patches simultaneously remove tissue surface hydration while retaining carbene-based photocuring and offers on-demand adhesion. The dry patch prototypes are optimized by controlling BC/adhesive mole ratios and dehydration technique. The adhesion strength is higher than commercial denture adhesives on soft mucosal tissues. The structural integrity is maintained for a minimum of 7 days in aqueous environment. The patches act as selective nanoporous barrier against bacteria while allowing permeation of proteins. The results support the application of BC-based adhesive patches as a flexible platform for wound dressings, drug depots, or combination thereof.

Environmental and health impacts of functional graphenic materials and their ultrasonically altered products.

Graphenic materials have excited the scientific community due to their exciting mechanical, thermal, and optoelectronic properties for a potential range of applications. Graphene and graphene derivatives have demonstrated application in areas stretching from composites to medicine; however, the environmental and health impacts of these materials have not been sufficiently characterized. Graphene oxide (GO) is one of the most widely used graphenic derivatives due to a relatively easy and scalable synthesis, and the ability to tailor the oxygen containing functional groups through further chemical modification. In this paper, ecological and health impacts of fresh and ultrasonically altered functional graphenic materials (FGMs) were investigated. Model organisms, specifically Escherichia coli, Bacillus subtilis, and Caenorhabditis elegans, were used to assess the consequences of environmental exposure to fresh and ultrasonically altered FGMs. FGMs were selected to evaluate the environmental effects of aggregation state, degree of oxidation, charge, and ultrasonication. The major findings indicate that bacterial cell viability, nematode fertility, and nematode movement were largely unaffected, suggesting that a wide variety of FGMs may not pose significant health and environmental risks.

Recent developments in supramolecular complexes of azabenzenes containing one to four N atoms: synthetic strategies, structures, and magnetic properties.

For the last couple of decades, azabenzene-based ligands have drawn much attention from inorganic chemists due to their ability to coordinate with different metal ions to form supramolecular clusters. These azabenzenes are weak σ donors and strong π acceptors and electron-deficient. Metallogrid complexes and non-grid oligomers are well-defined supramolecular clusters, formed by appropriate chelating ligands, and can show interesting optical, magnetic, and electronic properties. Self-assembly of [n × n] metallogrid complexes is dominated by the entropic factor while the formation of oligonuclear metal ion complexes is dominated by other effects like CFSE, electrostatic factors, ligand conformational characters, etc. Herein, the present article gives an overview of six-membered heterocyclic azine-based ligands and their potential for different metal ions to form polynuclear complexes. Moreover, their temperature-dependent magnetic properties and SCO phenomena are well described and tabulated.

Fibrillated bacterial cellulose liquid carbene bioadhesives for mimicking and bonding oral cavity surfaces.

Topical treatments for oral wounds and infections exhibit weak adhesion to wet surfaces which results in short retention duration (6-8 hours), frequent dosing requirement and patient incompatibility. To address these limitations, aqueous composites made of fibrillated bacterial cellulose and photoactive bioadhesives are designed for soft epithelial surfaces. The aqueous composites crosslink upon photocuring within a minute and exhibit a transition from viscous to elastic adhesive hydrogels. The light-cured composites have shear moduli mimicking oral mucosa and other soft tissues. The tunable adhesion strength ranges from 3 to 35 kPa on hydrated tissue-mimicking surfaces (collagen film). The results support the application of bacterial cellulose hydrogel systems for potential treatment of mucosal wounds.

Decoding the Mechanism of Specific RNA Targeting by Ribosomal Methyltransferases.

Methylation of specific nucleotides is integral for ribosomal biogenesis and also serves as a common mechanism to confer antibiotic resistance by pathogenic bacteria. Here, by determining the high-resolution structure of the 30S-KsgA complex by cryo-electron microscopy, a state was captured, where KsgA juxtaposes between helices h44 and h45 of the 30S ribosome, separating them, thereby enabling remodeling of the surrounded rRNA and allowing the cognate site to enter the methylation pocket. With the structure as a guide, several mutant versions of the ribosomes, where interacting bases in the catalytic helix h45 and surrounding helices h44, h24, and h27, were mutated and evaluated for their methylation efficiency revealing factors that direct the enzyme to its cognate site with high fidelity. The biochemical studies show that the three-dimensional environment of the ribosome enables the interaction of select loop regions in KsgA with the ribosome helices paramount to maintain selectivity.

mRNA Expression Analysis of E-Cadherin, VEGF, and MMPs in Gastric Cancer: a Pilot Study.

Gastric cancer (GC) is a serious fatal cancer on a global scale because of its presentation at advanced stage. The expressions of vascular endothelial growth factor (VEGF), E-cadherin, and matrix metalloproteinases (MMPs) in other cancers have been reported. However, its expression and underlying mechanisms are little known in gastric cancer in Indian context. In this study, we detected mRNA expression of VEGF, E-cadherin, and MMPs (MMP-1, MMP-2, and MMP-9) in 73 gastric cancer tissues and 27 normal controls by reverse-transcriptase polymerase chain reaction (RT-PCR). Receiver operator characteristics analysis was done for determining the diagnostic utility of VEGF, MMPs and E-cadherin with respect to the sensitivity and specificity. The association of VEGF, MMPs, and E-cadherin expression with the clinicopathological characteristics and the prognosis was subsequently analyzed. The mRNA expression results showed that E-cadherin was significantly downregulated in 47.9% of GC in comparison to control. There was no change in VEGF expression observed in 90.4% GC cases. MMP-1, MMP-2, and MMP-9 were overexpressed in 13.7%, 28.8%, and 11% of GC, respectively, with significant change in MMP-2 (p ≤ 0.0001) and MMP-9 (p = 0.027) in comparison to control. Our results strengthen the necessity of more studies to elucidate the prophetic role of these genes in the development of gastric cancer.

Bacterial cellulose adhesive composites for oral cavity applications.

Topical approaches to oral diseases require frequent dosing due to limited retention time. A mucoadhesive drug delivery platform with extended soft tissue adhesion capability of up to 7 days is proposed for on-site management of oral wound. Bacterial cellulose (BC) and photoactivated carbene-based bioadhesives (PDz) are combined to yield flexible film platform for interfacing soft tissues in dynamic, wet environments. Structure-activity relationships evaluate UV dose and hydration state with respect to adhesive strength on soft tissue mimics. The bioadhesive composite has an adhesion strength ranging from 7 to 17 kPa and duration exceeding 48 h in wet conditions under sustained shear forces, while other mucoadhesives based on hydrophilic macromolecules exhibit adhesion strength of 0.5-5 kPa and last only a few hours. The work highlights the first evaluation of BC composites for mucoadhesive treatments in the buccal cavity.