Background: Controlled drug delivery systems (DDS) are designed to release therapeutic agents in a regulated manner to maintain consistent plasma drug concentrations. Among these systems, gastro-retentive DDS (GRDDS) have gained considerable attention due to their ability to prolong gastric residence time, thereby enhancing drug bioavailability and therapeutic efficacy for drugs absorbed primarily in the stomach or upper gastrointestinal tract. Objectives: This review aimed to critically examine the role of pectin-based polymers in the development of GRDDS, with particular emphasis on formulation strategies using high- and low-methoxylated pectins. Results: Pectin, a naturally derived polysaccharide, is widely utilized in pharmaceutical formulations owing to its biocompatibility, biodegradability, non-toxic nature, and excellent gel-forming capacity. Based on its degree of methoxylation (DM), pectin is classified into high-methoxylated and low-methoxylated forms, each exhibiting distinct physicochemical and functional properties. Low-methoxylated pectin has been extensively explored in floating DDS due to its calcium-dependent gelation behavior. In contrast, high-methoxylated pectin demonstrates strong mucoadhesive properties, making it suitable for mucoadhesive gastro-retentive formulations. Comparative studies with other natural polymers highlight the versatility of pectin in GRDDS design. Conclusion: Pectin-based gastro-retentive formulations represent a promising and sustainable approach for controlled drug delivery. Understanding the distinct characteristics of high- and low-methoxylated pectin enables the rational design of effective GRDDS, potentially improving therapeutic outcomes and patient compliance.
urrently, antimicrobial resistance has become a major threat worldwide, hindering the effective functioning of antibiotics. Overcoming this challenge requires increasing antibiotic doses and, consequently, increasing toxicity. One of the researchers’ new strategy is to produce silver-antibiotic nanoconjugates.
Background: Vitamin D plays a notable role in regulating both innate and adaptive immunity. It supports the production of antimicrobial peptides, promotes autophagy, and helps control inflammatory signaling. These functions suggest that vitamin D may contribute to respiratory defense. However, the relationship between vitamin D levels and childhood pneumonia remains unclear and has shown inconsistent results in different studies. Objectives: To explore the biological mechanisms of vitamin D in respiratory immunity, evaluate the association between serum 25(OH)D levels and childhood pneumonia risk/severity, assess trial results in deficient versus replete populations, and identify sources of inconsistency across studies. Methods: This narrative review includes observational and interventional studies from several regions, such as South Asia, the Middle East, and Africa. We included studies that reported serum 25(OH)D levels, markers of pneumonia severity, and clinical outcomes in children. Special attention was given to mechanistic evidence, dose-response patterns, and differences in findings between vitamin D deficient and vitamin D adequate populations. Results: Observational studies show that children with pneumonia have lower vitamin D levels than healthy controls. Deficiency is associated with greater susceptibility, longer hospital stays, hypoxemia, and a higher risk of complications like sepsis. A dose-response relationship has been observed, where higher 25(OH)D levels are associated with less severe disease. However, randomized controlled trials have produced mixed results. Benefits, such as reduced recurrence and modest recovery improvements, are mainly seen in vitamin D deficient populations, with little to no effect in replete groups. These inconsistencies likely stem from differences in study design and a lack of detailed clinical endpoints. Conclusion: Observational studies associate low vitamin D with worse pneumonia outcomes in children, but randomized control trials show inconsistent results. Potential benefits (reduced recurrence, modest clinical improvement) appear mainly in deficient children, yet causality remains unproven due to heterogeneity in study design, deficiency definitions, and outcome measures. The lack of standardized pediatric vitamin D cutoffs (ranging from <12 to <20 ng/mL) limits clinical application. Rigorous prospective trials with uniform metrics are needed to establish causality and identify which deficient children benefit most.
Background: The search for environmentally friendly nanomaterials with strong antimicrobial activity has generated growing interest in using plants to produce nanoparticles. Objectives: This study aimed to biosynthesize and characterize iron (III) oxide (Fe2O3) nanoparticles stabilized by Luffa cylindrica extract and assess their antimicrobial properties. Methods: The biosynthesized Fe2O3 nanoparticles were characterized using ultraviolet–visible (UV–Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy to elucidate their optical, structural, morphological, and elemental properties. Results: The formation of Fe2O3 nanoparticles was confirmed by standard absorbance at 370 nm and functional groups attributed to the capping and stabilization observed via FTIR. XRD patterns showed a crystalline rhombohedral phase, and SEM images indicated that the nanoparticles were uniformly dispersed with diameters of 20-50 nm. Nanoparticle efficacy was tested using the agar well diffusion method against a panel of gram-positive and gram-negative bacterial strains and fungal pathogens. The results revealed substantial dose-dependent antimicrobial activity, with greater inhibitory activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, indicating potential broad-spectrum antimicrobial activity. Conclusion: This study highlights the potential of L. cylindrica-mediated Fe2O3 nanoparticles as sustainable and effective antimicrobial agents with potential application in the biomedical, pharmaceutical, and environmental fields.
Background: Saffron (Zaeferan in Persian), known as Red Gold, is obtained from the dried stigma of the Crocus sativus L. (Iridacea) plant. It plays a critical role in non-oil exporting in the economy of Iran, and the livelihoods of many farmers and workers depend on its yields. Burkholderia (Pseudomonas) gladioli pv. gladioli causes severe reductions the saffron yield in Iran. According to responsible authorities of Iran, no pesticides are registered or recommended for saffron cultivations (except for two herbicides). Most essential oils are listed as generally recognized as safe substances and can exhibit a crucial role in exporting pesticides free saffron. Objectives: The study aimed to identify the most effective antibacterial essential oils against B. gladioli pv. gladioli. Methods: Essential oils were extracted using a clevenger apparatus from 25 medicinal plants belonging to the Lamiaceae, Compositae, and Apiaceae families, followed by an initial evaluation through disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays. Dimethyl sulfoxide (DMSO) and amikacin served as a negative and positive control, respectively. Results: Out of 25 essential oils, only 4 of them exhibited antibacterial effects on this pathogen including Satureja hortensis (22.66 mm inhibition), Thymus vulgaris (20.33 mm), Trachyspermum ammi (17.66 mm), and Sclerorhachis leptoclada (10.66 mm). Their MICs were 1, 2, 4, and 32 µL/mL, respectively. Conclusion: These findings highlight promising essential oils for controlling B. gladioli, supporting pesticide-free saffron production and safeguarding Iran’s valuable crop yields.
