Low cost and biocompatible Marine algae derived scaffolds: enhancing tissue regeneration in oral cancer surgery.

Efficient tissue regeneration following oral cancer surgery is crucial for maintaining function. Seaweed-derived scaffold materials, with their resemblance to oral tissue structure, promote cell adhesion and differentiation. Their high porosity aids in exudate absorption, reducing infection risks and tissue maceration. Further scaffold breakdown releases growth factors, aiding tissue regeneration. Easily integrated into dressings or gels, these scaffolds accelerate healing and protect against contaminants. Their biocompatibility and safety ensure minimal adverse effects. Seaweed-derived scaffolds offer a natural, sustainable approach to tissue repair, making them ideal for post-oral surgery dressing, facilitating effective tissue regeneration.

Biosynthesis, characterization, and anticoagulant properties of copper nanoparticles from red seaweed of Acanthophora sp.

INTRODUCTION: In the last few decades, nanoparticles have found extensive use in a variety of biological applications. Traditional medicine widely uses Acanthophora sp., a marine macroalgae, to cure and prevent diabetes, skin disorders, and blood clotting. OBJECTIVE: The present study aims to investigate whether green-synthesized copper nanoparticles (CuNPs) might work as an anticoagulant. METHODOLOGY: The CuNPs were made using an environmentally friendly method that uses Acanthophora extract. We used UV-vis spectroscopy to assess the surface plasmon resonance of the material, scanning electron microscopy (SEM) to analyze its form, and energy dispersive X-ray (EDX) spectroscopy to identify the material's constituent elements. Furthermore, Fourier-transform infrared (FT-IR) determined the functional groups of the CuNPs. RESULTS: The biosynthesis of CuNPs was confirmed by UV-vis spectroscopy, which showed a surface plasmon resonance peak at 570 nm. The FT-IR analysis showed that certain functional groups are involved in the formation of CuNPs. These groups include OH stretching, C=O stretching, C-H bonding, C-N bonding, and Cu vibration. SEM analysis demonstrated the morphology of CuNPs synthesized, with a size of 0.5 µm, while EDS analysis confirmed their purity. The anticoagulant activity of prothrombin time (PT) and activated partial thromboplastin time (aPTT) assays showed that the clotting time got longer depending on the concentration. The CuNPs synthesized from Acanthophora had strong anticoagulant effects at 100 µg/mL, further suggesting that they might be useful as a natural blood thinner. CONCLUSION: The interesting thing we observed is that the green-synthesized CuNPs made from Acanthophora extract could be used in anticoagulation therapy.

Biosynthesis of Silver Nanoparticles From Marine Actinobacterium Micromonospora sp. and Their Bioactive Potential.

Background The biosynthesis of nanoparticles represents a rapid, environmentally friendly, cost-effective, and straightforward technology. This approach allows for the production of nanoparticles with a wide range of chemical compositions, sizes, shapes, high uniformity, and scalability. One of the principal advantages of biogenic nanoparticles is their water solubility and compatibility with biological systems. Biologically synthesized nanoparticles have demonstrated superior efficiency compared to conventionally synthesized particles. Among biosynthesis, microbial-mediated biosynthesis is a promising one that has a selectively reducing ability on specific metal ions through electron transfer.  Objectives Evaluation of antimicrobial and antioxidant activity of silver nanoparticle synthesized by actinobacteria Micromonospora sp. which is isolated from marine environment. Materials and methods In this study, actinobacteria were isolated from the marine sediment using the spread plate method. The isolates were identified based on morphological observation, cell wall amino acids, sugar analysis, and micromorphological analysis. The silver nanoparticle synthesis from microbes and their inhibition against clinical pathogens have been evaluated by the disc diffusion method. Antioxidant efficiency was evaluated in terms of total antioxidant activity through ammonium molybdenum assay. Results A total of five isolates were isolated from the sediment sample. The cell-free extract of MBIT-MSA4 can synthesize silver nanoparticles that have potential antimicrobial activity against the clinical pathogens Streptococcus mutans at a zone of inhibition 6 mm, 10 mm inhibition zone of Klebsiella pneumonia, and 8 mm zone of inhibition of Staphylococcus aureus. Also, it has significant antioxidant activity up to 73% of free radical inhibition. Conclusion Marine microbial-mediated biosynthesized silver nanoparticles have potential antimicrobial activity against S. mutans and methicillin-resistant Staphylococcus aureus (MRSA) and inhibit the oxidation process through antioxidant activity. This enhanced efficient biosynthesised nanoparticle has significantly reduced the concentration of free radicals caused by pathogens.

Control and prevention of microbially influenced corrosion using cephalopod chitosan and its derivatives: A review.

Microbially influenced corrosion (MIC) of metals is an important industrial problem, causing 300-500 billion dollars of economic loss worldwide each year. It is very challenging to prevent or control the MIC in the marine environment. Eco-friendly coatings embedded with corrosion inhibitors developed from natural products may be a successful approach for MIC prevention or control. As a natural renewable resource, cephalopod chitosan has a number of unique biological properties, such as antibacterial, antifungal and non-toxicity effects, which attract scientific and industrial interests for potential applications. Chitosan is a positively charged molecule, and the negatively charged bacterial cell wall is the target of its antimicrobial action. Chitosan binds to the bacterial cell wall and disrupts the normal functions of the membrane by, for example, facilitating the leakage of intracellular components and impeding the transport of nutrients into the cells. Interestingly, chitosan is an excellent film-forming polymer. Chitosan may be applied as an antimicrobial coating substance for the prevention or control of MIC. Furthermore, the antimicrobial chitosan coating can serve as a basal matrix, in which other antimicrobial or anticorrosive substances like chitosan nanoparticles, chitosan silver nanoparticles, quorum sensing inhibitors (QSI) or the combination of these compounds, can be embedded to achieve synergistic anticorrosive effects. A combination of field and laboratory experiments will be conducted to test this hypothesis for preventing or controlling MIC in the marine environment. Thus, the proposed review will identify new eco-friendly MIC inhibitors and will assay their potential in future applications in the anti-corrosion industry.

Scientific and Regulatory Policy Committee Points to Consider for Medical Device Implant Site Evaluation in Nonclinical Studies.

Nonclinical implantation studies are a common and often critical step for medical device safety assessment in the bench-to-market pathway. Nonclinical implanted medical devices or drug-device combination products require complex macroscopic and microscopic pathology evaluations due to the physical presence of the device itself and unique tissue responses to device materials. The Medical Device Implant Site Evaluation working group of the Society of Toxicologic Pathology's (STP) Scientific and Regulatory Policy Committee (SRPC) was tasked with reviewing scientific, technical, and regulatory considerations for these studies. Implant site evaluations require highly specialized methods and analytical schemes that should be designed on a case-by-case basis to address specific study objectives. Existing STP best practice recommendations can serve as a framework when performing nonclinical studies under Good Laboratory Practices and help mitigate limitations in standards and guidances for implant evaluations (e.g., those from the International Organization for Standardization [ISO], ASTM International). This article integrates standards referenced by sponsors and regulatory bodies with practical pathology evaluation methods for implantable medical devices and combination products. The goal is to ensure the maximum accuracy and scientific relevance of pathology data acquired during a medical device or combination drug-device implantation study.

A toxicogenomic approach for the risk assessment of the food contaminant acetamide.

Acetamide (CAS 60-35-5) is detected in common foods. Chronic rodent bioassays led to its classification as a group 2B possible human carcinogen due to the induction of liver tumors in rats. We used a toxicogenomics approach in Wistar rats gavaged daily for 7 or 28 days at doses of 300 to 1500 mg/kg/day (mkd) to determine a point of departure (POD) and investigate its mode of action (MoA). Ki67 labeling was increased at doses ≥750 mkd up to 3.3-fold representing the most sensitive apical endpoint. Differential gene expression analysis by RNA-Seq identified 1110 and 1814 differentially expressed genes in male and female rats, respectively, following 28 days of treatment. Down-regulated genes were associated with lipid metabolism while up-regulated genes included cell signaling, immune response, and cell cycle functions. Benchmark dose (BMD) modeling of the Ki67 labeling index determined the BMD10 lower confidence limit (BMDL10) as 190 mkd. Transcriptional BMD modeling revealed excellent concordance between transcriptional POD and apical endpoints. Collectively, these results indicate that acetamide is most likely acting through a mitogenic MoA, though specific key initiating molecular events could not be elucidated. A POD value of 190 mkd determined for cell proliferation is suggested for risk assessment purposes.

Lyophilized B. subtilis ZB183 Spores: 90-Day Repeat Dose Oral (Gavage) Toxicity Study in Wistar Rats.

A 90-day repeated-dose oral toxicological evaluation was conducted according to GLP and OECD guidelines on lyophilized spores of the novel genetically modified strain B. subtilis ZB183. Lyophilized spores at doses of 109, 1010, and 1011 CFU/kg body weight/day were administered by oral gavage to Wistar rats for a period of 90 consecutive days. B. subtilis ZB183 had no effects on clinical signs, mortality, ophthalmological examinations, functional observational battery, body weights, body weight gains and food consumption in both sexes. There were no test item-related changes observed in haematology, coagulation, urinalysis, thyroid hormonal analysis, terminal fasting body weights, organ weights, gross pathology and histopathology. A minimal increase in the plasma albumin level was observed at 1010 and 1011 CFU/kg/day doses without an increase in total protein in males or females and was considered a nonadverse effect. The "No Observed Adverse Effect Level (NOAEL)" is defined at the highest dose of 1011 CFU/kg body weight/day for lyophilized B. subtilis ZB183 Spores under the test conditions employed.

Acute Histopathologic Findings Related to Needle Puncture Trauma during Subcutaneous Injection in the Sprague-Dawley Rat Model.

It is important to detect injection site reactions during the nonclinical phases of drug development. However, differentiating between normal changes following needle trauma and changes due to the toxicity of injected drugs can be challenging. Therefore, we used the Sprague-Dawley rat model to evaluate the pathological findings expected following a single subcutaneous injection of normal saline. Rats were subcutaneously administered with normal saline, and the injection sites were examined microscopically. Inflammation was evident in most of the injection sites, mostly in minimal severity. Parakeratosis/epithelial crust was also seen in several sites, and necrosis was observed in a minority of the cases. These findings indicate that needle puncture trauma can present with some degree of inflammation and necrosis. Although limited to a specific time point and strain, this study shows that inflammation following subcutaneous injection can be attributed in part to the needle trauma and not necessarily to the drug itself.

Reversibility of dopamine receptor antagonist-induced hyperprolactinemia and associated histological changes in Tg RasH2 wild-type mice.

The purpose of this study was to better understand the biological effects of increased prolactin levels induced in mice by dopamine D2 receptor antagonist molindone treatment. Toxicokinetics, prolactin levels, and reproductive tissue histology were evaluated in Tg rasH2 wild-type mice treated orally with molindone at 0, 5, 15, and 50mg/kg/day for 6 months, followed by a 2-month posttreatment recovery period. A greater than dose-proportional increase in molindone exposure ([AUC]0‒24) was observed on Day 180 for both sexes. Statistically significant (P<0.01) increases in prolactin levels were observed in most treatment groups compared with controls at 0.5h postdose on Days 1 and 180. Prolactin levels returned to baseline levels during the recovery period. Microscopic changes attributable to hyperprolactinemia, including corpora lutea enlargement and interstitial cell atrophy in the ovaries, and atrophy of the uterus and vagina were observed on Day 180. These changes were reversed during the recovery period in the 5- and 15-mg/kg/day treatment groups. Mice receiving molindone at 50mg/kg/day also showed signs of reversal on histologic examination.

Bar retained dento-alveolar prosthesis: a case report.

A technique for restoring missing anterior teeth with associated extensive alveolar bone loss has been presented. This technique combines fixed and removable restorations where in removable prosthesis that restores the alveolar defect gets attached to the fixed prosthesis through precision attachment. The fixed prosthesis contributes to esthetics, function and also elevates patient's self image. The removable prosthesis provides the much needed soft tissue support and also facilitates oral hygiene maintenance.

Multidisciplinary approach of ectodermal dysplasia with implant retained fixed prosthesis.

Ectodermal dysplasia represents a group of rare inherited conditions in which two or more ectodermally derived anatomical structures fail to develop. Early dental intervention can improve patient's appearance, thereby minimizing associated emotional and psychological problems in these patients. Treatment requires a teamwork by medical personnel along with dental professionals of various specialties. Here, a rare case of a young female patient is presented with prosthetic management with implant supported fixed partial denture.