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International Journal of Pharmaceutics Jun 2024Schizophrenia is a psychiatric disorder that results from abnormal levels of neurotransmitters in the brain. Risperidone (RIS) is a common drug prescribed for the...
Schizophrenia is a psychiatric disorder that results from abnormal levels of neurotransmitters in the brain. Risperidone (RIS) is a common drug prescribed for the treatment of schizophrenia. RIS is a hydrophobic drug that is typically administered orally or intramuscularly. Transdermal drug delivery (TDD) could potentially improve the delivery of RIS. This study focused on the development of RIS nanocrystals (NCs), for the first time, which were incorporated into dissolving microneedle array patches (DMAPs) to facilitate the drug delivery of RIS. RIS NCs were formulated via wet-media milling technique using poly(vinylalcohol) (PVA) as a stabiliser. NCs with particle size of 300 nm were produced and showed an enhanced release profile up to 80 % over 28 days. Ex vivo results showed that 1.16 ± 0.04 mg of RIS was delivered to both the receiver compartment and full-thickness skin from NCs loaded DMAPs compared to 0.75 ± 0.07 mg from bulk RIS DMAPs. In an in vivo study conducted using female Sprague Dawley rats, both RIS and its active metabolite 9-hydroxyrisperidone (9-OH-RIS) were detected in plasma samples for 5 days. In comparison with the oral group, DMAPs improved the overall pharmacokinetic profile in plasma with a ∼ 15 folds higher area under the curve (AUC) value. This work has represented the novel delivery of the antipsychotic drug, RIS, through microneedles. It also offers substantial evidence to support the broader application of MAPs for the transdermal delivery of poorly water-soluble drugs.
PubMed: 38880253
DOI: 10.1016/j.ijpharm.2024.124342 -
Chemical Science Jun 2024Full dechlorination of poly(vinyl chloride) (PVC) in a controlled manner to yield useful polymeric and chlorinated products is of great interest for the processing of...
Full dechlorination of poly(vinyl chloride) (PVC) in a controlled manner to yield useful polymeric and chlorinated products is of great interest for the processing of PVC waste. Forming polyethylene (PE) without corrosive by-products would allow for a pre-treatment of PE wastes that are often contaminated with PVC. Herein, full dechlorination of PVC has been achieved generation of silylium ions , to furnish PE products. Complete dechlorination of PVC can be achieved in 2 hours, yielding organic polymer that has similar spectroscopic and thermal signatures of branched PE, with no observable chlorine. The degree of branching can be tuned between 31 and 57 branches per 1000 carbons, with melting temperatures ranging from 51 to 93 °C. This method is applicable to not only pure PVC, but also commercial PVC products. Depending on if the PVC products are separated from plasticizers, different melting points of the resulting PE are observed. PVC dechlorination in the presence of PE waste is also shown. This is the first report of being able to cleanly convert PVC waste to PE in high yields and tune the thermal properties of the PE product, highlighting the remarkable control that silylium ion mediated transformations enables compared to past chemical methods.
PubMed: 38873082
DOI: 10.1039/d4sc00130c -
Heliyon Jun 2024The knowledge of the polymeric composition of microplastics (MPs) is interesting because offers useful information on the resistance, durability, and degradability of...
The knowledge of the polymeric composition of microplastics (MPs) is interesting because offers useful information on the resistance, durability, and degradability of these materials, also allowing progress in the control of this contamination. However, there is currently a lack of reliable standardized methods for the identification, and characterization of the plastic microparticles. This work uses different techniques in a complementary manner for the identification, and characterization of MPs that more frequently are found in the environment. A total of 10 types of plastics were collected (polystyrene (PS), polyethylene terephthalate (PETE), polyethylene (PE), high- and low-density polyethylene (HDPE and LDPE, respectively), polyvinyl chloride (PVC), polypropylene (PP), polytetrafluoroethylene (PTFE), Polyamide (PA, Nylon 6,6) and poly-carbonate (PC)) and their chemical identification were analyzed by reflectance-attenuated infrared (FTIR-ATR). Furthermore, the samples were observed using light microscopy, and scan-ning electron microscopy (SEM). Also, staining with 12 different dyes was performed to improve the identification of microplastics. The results of this study revealed that PETE, PE, HDPE and LDPE, whose SEM images exhibited smoothness and flat uniformity of their surface, were not (or less) susceptible to adsorb staining solutions while PP, PA, PVC, and PTFE, were capable of adsorbing the dye solutions.
PubMed: 38867989
DOI: 10.1016/j.heliyon.2024.e30749 -
BMC Urology Jun 2024Neurogenic bladder dysfunction is a major problem for spinal cord injury (SCI) patients not only due to the risk of serious complications but also because of the impact... (Comparative Study)
Comparative Study
BACKGROUND
Neurogenic bladder dysfunction is a major problem for spinal cord injury (SCI) patients not only due to the risk of serious complications but also because of the impact on quality of life. The main aim of this study is to compare the rate of urinary tract infection (UTI) associated with hydrophilic-coated catheters versus uncoated polyvinyl chloride (PVC) catheters among SCI patients presenting with functional neurogenic bladder sphincter disorders.
METHODOLOGY
This was a retrospective cohort study from 2005 to 2020 including adult male or female patients who have an SCI at least more than 1 month ago with neurogenic bladder dysfunction and were using intermittent catheterization (single-use hydrophilic-coated or the standard-of-care polyvinyl chloride uncoated standard catheters) at least 3 times a day to maintain bladder emptying.
RESULTS
A total of 1000 patients were selected and recruited through a stratified random sampling technique with 467 (47.60%) patients in the uncoated catheter arm and 524 (52.60%) in the coated catheter groups. The three outcome measures, namely: symptomatic UTI, Bacteriuria, and pyuria were significantly higher in the group using uncoated polyvinyl chloride (PVC) catheters compared to hydrophilic-coated catheters at the rate of 79.60% vs.46.60%, 81.10% vs. 64.69, and 53.57% versus 41.79% respectively. Males, elder patients, longer duration, and severity of SCI were associated with increased risk of symptomatic UTI.
CONCLUSIONS
The results indicate a beneficial effect regarding clinical UTI when using hydrophilic-coated catheters in terms of fewer cases of symptomatic UTI. Bacteriuria is inevitable in patients with long-term catheterization, however, treatment should not be started unless the clinical symptoms exist. More attention should be given to the high-risk group for symptomatic UTIs.
Topics: Humans; Retrospective Studies; Spinal Cord Injuries; Male; Female; Urinary Tract Infections; Middle Aged; Adult; Urinary Bladder, Neurogenic; Urinary Catheters; Intermittent Urethral Catheterization; Hydrophobic and Hydrophilic Interactions; Polyvinyl Chloride; Cohort Studies; Aged; Urinary Catheterization; Catheter-Related Infections
PubMed: 38867233
DOI: 10.1186/s12894-024-01510-y -
Journal of Cellular and Molecular... Jun 2024Chemotherapy resistance remains a significant challenge in treating ovarian cancer effectively. This study addresses this issue by utilizing a dual drug-loaded...
Chemotherapy resistance remains a significant challenge in treating ovarian cancer effectively. This study addresses this issue by utilizing a dual drug-loaded nanomicelle system comprising albendazole (ABZ) and paclitaxel (PTX), encapsulated in a novel carrier matrix of D-tocopheryl polyethylene glycol 1000 succinate vitamin E (TPGS), soluplus and folic acid. Our objective was to develop and optimize this nanoparticulate delivery system using solvent evaporation techniques to enhance the therapeutic efficacy against ovarian cancer. The formulation process involved pre-formulation, formulation, optimization, and comprehensive characterization of the micelles. Optimization was conducted through a 32 factorial design, focusing on the effects of polymer ratios on particle size, zeta potential, polydispersity index (PDI) and entrapment efficiency (%EE). The optimal formulation demonstrated improved dilution stability, as indicated by a critical micelle concentration (CMC) of 0.0015 mg/mL for the TPGS-folic acid conjugate (TPGS-FOL). Extensive characterization included differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), and Fourier-transform infrared spectroscopy (FTIR). The release profile exhibited an initial burst followed by sustained release over 90 h. The cytotoxic potential of the formulated micelles was superior to that of the drugs alone, as assessed by MTT assays on SKOV3 ovarian cell lines. Additionally, in vivo studies confirmed the presence of both drugs in plasma and tumour tissues, suggesting effective targeting and penetration. In conclusion, the developed TPGS-Fol-based nanomicelles for co-delivering ABZ and PTX show promising results in overcoming drug resistance, enhancing solubility, sustaining drug release, and improving therapeutic outcomes in ovarian cancer treatment.
Topics: Female; Paclitaxel; Micelles; Albendazole; Ovarian Neoplasms; Humans; Animals; Cell Line, Tumor; Drug Carriers; Polyethylene Glycols; Vitamin E; Folic Acid; Mice; Drug Liberation; Particle Size; Polyvinyls; Polymers; Xenograft Model Antitumor Assays
PubMed: 38864691
DOI: 10.1111/jcmm.18389 -
RSC Advances Jun 2024Silver nanoparticles (AgNPs) were loaded on deprotonated cellulose nanocrystals (CNCd) and incorporated into polyvinyl alcohol (PVA) to develop novel active food...
Silver nanoparticles (AgNPs) were loaded on deprotonated cellulose nanocrystals (CNCd) and incorporated into polyvinyl alcohol (PVA) to develop novel active food packaging films. The AgNPs were fabricated using the liquid phase chemical reduction method using the sodium borohydride reductant of AgNO. The analysis using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), and Ultraviolet-visible spectroscopy (UV-Vis) showed that the CNCd surface had a homogeneous distribution of AgNPs with a diameter of about 100 nm. Additionally, CNCd/Ag was successfully incorporated into the PVA film. The developed PVA/CNCd/Ag film showed significantly improved mechanical properties, thermal stability, and UV barrier properties compared to a neat PVA film. The PVA/CNCd/Ag composite film could significantly preserve bananas for 14 days, preventing deterioration and allowing extended storage periods. This composite film generally shows promise in food packaging and prolongs food's shelf life.
PubMed: 38863813
DOI: 10.1039/d4ra02085e -
International Journal of Nanomedicine 2024The healing of burn wounds is a complicated physiological process that involves several stages, including haemostasis, inflammation, proliferation, and remodelling to...
BACKGROUND
The healing of burn wounds is a complicated physiological process that involves several stages, including haemostasis, inflammation, proliferation, and remodelling to rebuild the skin and subcutaneous tissue integrity. Recent advancements in nanomaterials, especially nanofibers, have opened a new way for efficient healing of wounds due to burning or other injuries.
METHODS
This study aims to develop and characterize collagen-decorated, bilayered electrospun nanofibrous mats composed of PVP and PVA loaded with Resveratrol (RSV) and Ampicillin (AMP) to accelerate burn wound healing and tissue repair.
RESULTS
Nanofibers with smooth surfaces and web-like structures with diameters ranging from 200 to 400 nm were successfully produced by electrospinning. These fibres exhibited excellent in vitro properties, including the ability to absorb wound exudates and undergo biodegradation over a two-week period. Additionally, these nanofibers demonstrated sustained and controlled release of encapsulated Resveratrol (RSV) and Ampicillin (AMP) through in vitro release studies. The zone of inhibition (ZOI) of PVP-PVA-RSV-AMP nanofibers against ( and () was found 31±0.09 mm and 12±0.03, respectively, which was significantly higher as compared to positive control. Similarly, the biofilm study confirmed the significant reduction in the formation of biofilms in nanofiber-treated group against both and . X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis proved the encapsulation of RSV and AMP successfully into nanofibers and their compatibility. Haemolysis assay (%) showed no significant haemolysis (less than 5%) in nanofiber-treated groups, confirmed their cytocompatibility with red blood cells (RBCs). Cell viability assay and cell adhesion on HaCaT cells showed increased cell proliferation, indicating its biocompatibility as well as non-toxic properties. Results of the in-vivo experiments on a burn wound model demonstrated potential burn wound healing in rats confirmed by H&E-stained images and also improved the collagen synthesis in nanofibers-treated groups evidenced by Masson-trichrome staining. The ELISA assay clearly indicated the efficient downregulation of TNF-alpha and IL-6 inflammatory biomarkers after treatment with nanofibers on day 10.
CONCLUSION
The RSV and AMP-loaded nanofiber mats, developed in this study, expedite burn wound healing through their multifaceted approach.
Topics: Resveratrol; Nanofibers; Burns; Wound Healing; Animals; Collagen; Povidone; Staphylococcus aureus; Polyvinyl Alcohol; Humans; Escherichia coli; Ampicillin; Anti-Bacterial Agents; Rats; Biofilms; Male
PubMed: 38863647
DOI: 10.2147/IJN.S464046 -
STAR Protocols Jun 2024Approaches for detecting micro(nano)plastics (MNPs) released from intravenous infusion products (IVIPs) are vital for evaluating the safety of both IVIPs and their...
Approaches for detecting micro(nano)plastics (MNPs) released from intravenous infusion products (IVIPs) are vital for evaluating the safety of both IVIPs and their derived MNPs on human health, yet current understanding is limited. Here, we present a protocol for detecting polyvinyl chloride (PVC) MNPs by combining Raman spectroscopy, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDS), and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). We describe steps for collecting, pretreating, and measuring PVC MNPs released from IVIPs. For complete details on the use and execution of this protocol, please refer to Li et al..
Topics: Spectrum Analysis, Raman; Infusions, Intravenous; Gas Chromatography-Mass Spectrometry; Polyvinyl Chloride; Humans; Microscopy, Electron, Scanning; Spectrometry, X-Ray Emission; Plastics
PubMed: 38861383
DOI: 10.1016/j.xpro.2024.103104 -
Wounds : a Compendium of Clinical... May 2024Diabetic foot ulcers (DFUs) pose significant challenges for patients, often leading to chronic inflammation, reduced mobility, and chronic pain. Despite being less... (Clinical Trial)
Clinical Trial
BACKGROUND
Diabetic foot ulcers (DFUs) pose significant challenges for patients, often leading to chronic inflammation, reduced mobility, and chronic pain. Despite being less prevalent in the United States compared to other nations, the economic burden of DFUs remains substantial, with an estimated annual cost ranging from $9 billion to $13 billion. Furthermore, DFUs are a leading cause of nontraumatic lower extremity amputations and significantly impact health care systems and work productivity.
OBJECTIVE
This study aimed to evaluate the effectiveness of a polyvinyl alcohol (PVA) foam dressing containing gentian violet/methylene blue (GV/MB) in managing chronic DFUs.
MATERIALS AND METHODS
A single-center study was conducted involving 20 patients with full-thickness chronic lower extremity wounds, including DFUs. Patients received treatment with a PVA foam dressing with GV/MB applied in an outpatient setting over a period of 4 weeks. Wound size, bacterial presence, and healing progress were assessed using fluorescence imaging and wound measurements.
RESULTS
The study included 13 males and 7 females with an average age of 64.2 years. After 4 weeks of treatment, the average DFU size decreased by 53%, with 4 patients achieving complete wound closure. Reduction in ulcer size was strongly correlated with the use of surgical debridement and PVA GV/MB foam. Fluorescence imaging demonstrated a significant reduction in bacterial presence in all patients by the end of the study. Follow-up at 3 and 6 months showed no recurrent ulcerations, indicating the potential for long-term efficacy.
CONCLUSION
The findings suggest that PVA GV/MB foam dressings, when combined with surgical debridement, are effective in promoting the healing of chronic DFUs. Further research with larger, controlled studies is warranted to confirm these findings and assess cost-effectiveness.
Topics: Humans; Diabetic Foot; Male; Female; Polyvinyl Alcohol; Debridement; Middle Aged; Wound Healing; Prospective Studies; Treatment Outcome; Aged; Anti-Bacterial Agents; Bandages
PubMed: 38861211
DOI: 10.25270/wnds/23008 -
Microbiology Resource Announcements Jun 2024We present the metagenome-assembled genome sequences of two polyvinyl alcohol-degrading co-colony-derived bacterial species relative to sp. DHB23 and ATCC 14581. We...
We present the metagenome-assembled genome sequences of two polyvinyl alcohol-degrading co-colony-derived bacterial species relative to sp. DHB23 and ATCC 14581. We estimated the genomes of these species to be 3,476,996- and 5,169,587-bp long (for sp. DHB23 and ATCC 14581, respectively).
PubMed: 38860814
DOI: 10.1128/mra.00363-24