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Journal of Neuroimaging : Official... 2023Dural arteriovenous fistulas (DAVFs) with cortical venous drainage (CVD) carry significant risks of cerebral ischemia and intracranial hemorrhage. Endovascular treatment...
BACKGROUND AND PURPOSE
Dural arteriovenous fistulas (DAVFs) with cortical venous drainage (CVD) carry significant risks of cerebral ischemia and intracranial hemorrhage. Endovascular treatment (EVT) using Onyx, a copolymer-based liquid embolic material, has become the preferred approach. However, the optimal treatment strategy for anterior cranial fossa DAVFs remains debated.
METHODS
This retrospective study analyzed outcomes of EVT for DAVFs in a single center from 2002 to 2023. Patient data including demographics, clinical status, angiographic findings, embolization techniques, and outcomes were recorded. The results of the anterior fossa malformations were analyzed separately afterward.
RESULTS
A total of 195 DAVFs were included in the study. The most common presenting symptom was hemorrhage (41%), most fistulas were located in the transverse and sigmoid sinus region (48%), and the majority of DAVFs had direct CVD (78%). Transarterial embolization with Onyx was the preferred treatment strategy in majority of cases (92%). Overall, 94% of patients showed improvement or stability on the modified Rankin Scale. Two patients died due to rebleeding after partial DAVF embolization. Onyx demonstrated higher immediate complete occlusion rate compared to other embolic materials (88% vs. 35%). Overall, 91% of fistulas were closed at the last follow-up. Ten anterior fossa DAVFs were treated, resulting in clinical improvement and complete occlusion in all cases.
CONCLUSION
Based on the results of our study, we believe that a cure of DAVFs, including those in the anterior fossa, can be achieved in more than 90% of cases through transarterial Onyx embolization, given long-term clinical experience.
Topics: Humans; Treatment Outcome; Retrospective Studies; Polyvinyls; Central Nervous System Vascular Malformations; Embolization, Therapeutic; Fistula
PubMed: 37602898
DOI: 10.1111/jon.13148 -
BMC Research Notes Oct 2023Polyvinyl alcohol (PVA) as a synthetic biopolymer has unique physicochemical properties to achieve an efficient drug carrier. In this study phenol-substituted polyvinyl...
OBJECTIVE
Polyvinyl alcohol (PVA) as a synthetic biopolymer has unique physicochemical properties to achieve an efficient drug carrier. In this study phenol-substituted polyvinyl alcohol (PVAPh) microparticle was made through a microfluidic system and peroxidase-mediated reaction in the presence of hydrogen peroxide and in following dexamethasone (Dex) release characteristics from this vehicle were elaborated for sustained drug delivery applications.
RESULTS
PVAPh was synthesized by esterification and amidation reactions respectively. Then, the synthesized PVAPh solution containing peroxidase and Dex flowed within the inner channel of the coaxial microfluidic device while liquid paraffin saturated with HO flowed from the outer channel. The monodisperse microparticles were produced in a spherical shape with an average diameter of 160 μm. The Dex was successfully encapsulated in PVAPh MP and its sustained release profile was maintained for up to 7 days. It was found that exposure of Dex-loaded PVAPh MPs to subcultured mouse embryonic fibroblast 10T1/2 cells had no deleterious effects on cell viability, morphology and growth rate. Moreover, the sustained release of Dex and the high mechanical durability of PVAPh MPs suggest an excellent prospect for the synthesized PVAPh and the developed method as a biocompatible carrier required for drug delivery and regenerative medicine.
Topics: Animals; Mice; Polyvinyl Alcohol; Delayed-Action Preparations; Microfluidics; Hydrogen Peroxide; Fibroblasts; Dexamethasone; Peroxidases
PubMed: 37828608
DOI: 10.1186/s13104-023-06544-3 -
Journal of Medical Case Reports Apr 2024S-lon® (S) is a locally produced polyvinyl chloride-based solvent cement. It is a clear, slightly viscous liquid. Other constituents include 1-cyclohexanone,...
BACKGROUND
S-lon® (S) is a locally produced polyvinyl chloride-based solvent cement. It is a clear, slightly viscous liquid. Other constituents include 1-cyclohexanone, 3-butanone, and 1-acetone. It is used ubiquitously for building construction in Sri Lanka. Although the clinical effects of the compound have not yet been ascertained, the constituents have been implicated in neurotoxicity, respiratory tract, eye and skin irritation, and delayed liver and renal injury.
CASE DESCRIPTION
A 42-year-old South Asian male presented following self-ingestion of S. His vital parameters were stable and initially managed symptomatically. A few hours later, he developed central nervous system depression and stridor requiring elective intubation. Examination of the upper airway revealed inflammation and edema. He was sedated and ventilated, and intravenous dexamethasone was administered. Attempts at removal of the nasogastric tube after extubation on day 3 failed. The patient had to be reintubated and sedated owing to extreme agitation not responding to routine doses of sedatives. The nasogastric tube had been amalgamated after reacting with S, forming a solid clump, later found after removal. The posterior pharynx and nasopharynx were packed and later removed before extubation. The patient made a full recovery and was transferred to the ward on day 5.
CONCLUSION
Ingestion of a sufficient quantity of S could result in gut absorption with central nervous system depression, coma, and even death. No antidote is available for toxicity, and management is largely supportive. As witnessed in our patient, chemical laryngitis and upper airway inflammation may lead to upper airway obstruction. Chemical reactions with medical equipment may lead to unforeseen outcomes.
Topics: Humans; Male; Adult; Polyvinyl Chloride; Edema; Antidotes; Inflammation; Solvents
PubMed: 38581068
DOI: 10.1186/s13256-024-04470-x -
International Journal of Biological... Jul 2023The design and preparation of novel renewable biomass-based dielectric composites have drawn great attention recently. Here, cellulose was dissolved in NaOH/urea aqueous...
The design and preparation of novel renewable biomass-based dielectric composites have drawn great attention recently. Here, cellulose was dissolved in NaOH/urea aqueous solution, and AlO nanosheets (AONS) synthesized by hydrothermal method were used as fillers. Then the regenerated cellulose (RC)-AONS dielectric composite films were prepared by regeneration, washing and drying. The two-dimensional AONS had a better effect on improving the dielectric constant and breakdown strength of the composites, so that the RC-AONS composite film with 5 wt% AONS content reached an energy density of 6.2 J/cm at 420 MV/m. Furthermore, in order to improve the dielectric energy storage properties of cellulose films in high humidity environment, the hydrophobic polyvinylidene fluoride (PVDF) was innovatively introduced to construct RC-AONS-PVDF composite films. The energy storage density of the prepared ternary composite films could reach 8.32 J/cm at 400 MV/m, which was 416 % improvement against that of the commercially biaxially oriented polypropylene (2 J/cm), and could be cycled for >10,000 times under 200 MV/m. Concurrently, the water absorption of the composite film in humidity was effectively reduced. This work broadens the application prospect of biomass-based materials in the field of film dielectric capacitor.
Topics: Polyvinyls; Biomass; Cellulose; Desiccation
PubMed: 37285894
DOI: 10.1016/j.ijbiomac.2023.125220 -
International Journal of Biological... Dec 2023Biocompatibility hydrogel conductors are considered as sustainable bio-electronic materials for the application of wearable sensors and implantable devices. However,...
Biocompatibility hydrogel conductors are considered as sustainable bio-electronic materials for the application of wearable sensors and implantable devices. However, they mostly face the limitations of mismatched mechanical properties with skin tissue and the difficulty of recycling. In this regard, here, a biocompatible, tough, reusable sensor based on physical crosslinked polyvinyl alcohol (PVA) ionic hydrogel modified with ι-carrageenan (ι-CG) helical network was reported. Through simulating the ion transport and network structure of biological systems, the ionic hydrogels with skin-like mechanical features exhibit large tensile strain of 640 %, robust fracture strength of 800 kPa, soft modulus and high fatigue resistance. Meanwhile, the ionic hydrogel-based sensors possess a high response to strain/pressure over a wide range and could be utilized for multimodal sensing of human activity signals. Benefit from biosafety and temperature reversibility of ι-CG and PVA endow hydrogels with not only biocompatibility, but also meaningfully recyclability. The as-prepared hydrogels could be freely reconstructed into new flexible electronics and safely integrated with the human skin. It could be anticipated that the physically cross-linked ionic hydrogel conductor could expand the options for next-generation bio-based sensors.
Topics: Humans; Polyvinyl Alcohol; Carrageenan; Temperature; Hydrogels; Ions; Electric Conductivity
PubMed: 37734518
DOI: 10.1016/j.ijbiomac.2023.126954 -
Journal of the Mechanical Behavior of... Apr 2024Postoperative abdominal adhesions often occur after abdominal surgery; barrier membranes which mimic peritoneal tissue can be constructed to prevent abdominal adhesions....
Postoperative abdominal adhesions often occur after abdominal surgery; barrier membranes which mimic peritoneal tissue can be constructed to prevent abdominal adhesions. To this end, silk fibroin (SF) sheets were coated with polyvinyl alcohol (PVA) and agarose (AGA) at PVA:AGA ratios of 100:0, 70:30, 50:50, 30:70, and 0:100 to create a composite anti-adhesive barrier and allow us to identify a suitable coating ratio. The membranes were characterized in terms of their molecular organization, structure, and morphology using Fourier transform Infrared spectrometer (FT-IR), differential scanning calorimeter (DSC), and scanning electron microscope (SEM), respectively. The physical and mechanical properties of the membranes and their biological performance (i.e., fibroblast proliferation and invasion) were tested in vitro. Each membrane showed both smooth and rough surface characteristics. Membranes coated with PVA:AGA at ratios of 100:0, 70:30, 50:50, and 30:70 exhibited more -OH and amide III moieties than those coated with 0:100 PVA:AGA, which consequently affected structural organization, degradation, and fibroblast viability. The 0:100 PVA:AGA-coated degraded the fastest. Barrier membranes coated with 100:0 and 70:30 PVA: AGA demonstrated reduced fibroblast proliferation and attachment. The membrane coated with 70:30 PVA:AGA exhibited a stable appearance, and did not curl under wet conditions. Therefore, SF sheets coated with 70:30 PVA:AGA show promise as anti-adhesive barrier membranes for further development.
Topics: Spectroscopy, Fourier Transform Infrared; Membranes; Amides; Fibroblasts; Fibroins; Polyvinyl Alcohol; Sepharose
PubMed: 38281440
DOI: 10.1016/j.jmbbm.2024.106417 -
Poultry Science Jul 2024Baicalein (BAI) is a natural flavonoid with antioxidant, antitumor and antibacterial properties. However, the bioavailability of BAI was limited due to low solubility....
The baicalein amorphous solid dispersion to enhance the dissolution and bioavailability and effects on growth performance, meat quality, antioxidant capacity and intestinal flora in Taihang chickens.
Baicalein (BAI) is a natural flavonoid with antioxidant, antitumor and antibacterial properties. However, the bioavailability of BAI was limited due to low solubility. This study aims to improve the solubility of BAI through the amorphous solid dispersion (ASD) and evaluate changes in its pharmacokinetics and pharmacodynamics in Taihang chickens. Polyethylene caprolactam-polyvinyl acetate-polyethylene glycol grafted copolymer (Soluplus) was chosen as the carrier, and ASD was prepared by rotary evaporation and was characterized by powder X-ray diffractions (PXRD), differential scanning calorimetry (DSC) and fourier transform infrared spectroscopy (FT-IR). In vitro dissolution assays were used to screen the optimal ratio of drug to carrier, in vivo pharmacokinetic assays were conducted to investigate the promoting effect on the absorption. In addition, the effects of ASD on the growth performance, meat quality, antioxidant capacity and intestinal flora were investigated. ASD (1:9 and 2:8) did not exhibit crystal diffraction peaks of BAI in PXRD or endothermic peaks in DSC, indicating the successful preparation of ASD. The results of in vitro dissolution assay showed that the cumulative dissolution rate of ASD (2:8) within 600 min was 52.67%, which was 7.84-fold higher than BAI. The pharmacokinetic results showed that the peak concentration (C) and the area under the drug-time curve (AUC) of ASD (2:8) was (5.20 ± 0.82) μg/mL and (17.03 ± 0.67) μg·h/mL, which was 1.91 and 2.64-fold higher than BAI, respectively. Dietary supplementation of BAI and ASD could increase average daily gain (ADG), while decrease feed conversion ratio (FCR), but there was no significant difference (P > 0.05). The drip loss of BAIASD group was lower than BAI group (P < 0.05). In addition, the antioxidant capacity of Taihang chickens were enhanced, the diversity and the abundance of beneficial bacteria was improved. Results of BAI upon the dietary supplementation tested in Taihang chickens, after preparation of ASD, indicating a superior enhancement effect in growth performance, meat quality, antioxidant capacity and intestinal flora due to an improved solubility and optimized bioavailability.
Topics: Animals; Chickens; Biological Availability; Antioxidants; Flavanones; Meat; Animal Feed; Gastrointestinal Microbiome; Solubility; Diet; Polyvinyls; Male; Polyethylene Glycols; Dietary Supplements
PubMed: 38703758
DOI: 10.1016/j.psj.2024.103768 -
International Journal of Biological... Dec 2023Hydrogels, owing to their unique porous structures, hydrophilic properties, and biocompatibility, are being developed as scaffolds for bone grafts. However, the use of...
Hydrogels, owing to their unique porous structures, hydrophilic properties, and biocompatibility, are being developed as scaffolds for bone grafts. However, the use of toxic initiators or cross-linking agents is a drawback. To overcome this, we developed Laponite®/cross-linked starch/polyvinyl alcohol (PVA) hydrogels prepared by one-step solution mixing. The structure, rheological properties, and biocompatibility of the hydrogels were investigated. Zeta potential, Fourier transform infrared, and X-ray diffraction analyses showed that hydrogen bonding and electrostatic interactions jointly maintained the structure of the cross-linked hydrogel systems. At a Laponite® concentration of 10 %, the hydrogel with a starch/PVA ratio of 2:2 exhibited a uniform porous structure, the highest storage modulus (G'), and the lowest degradation rate. At a starch/PVA ratio of 2:2, the G' increased; however, the degradation rate decreased with the increase in Laponite® content from 5 % to 20 %. These results indicate that the mechanical strength and degradation rate of the hydrogels could be adjusted by altering the starch/PVA ratio and the amount of Laponite®. In vitro cytotoxicity experiments showed that the Laponite®/starch/PVA (LSP) hydrogels were non-toxic to MC3T3-E1 cells. The starch/PVA ratio had no obvious effect on the proliferation of MC3T3-E1 cells, but an increase in Laponite® content significantly promoted cell proliferation. In summary, the results suggest that these LSP hydrogels have great potential for applications in bone tissue engineering.
Topics: Starch; Polyvinyl Alcohol; Hydrogels
PubMed: 37879585
DOI: 10.1016/j.ijbiomac.2023.127618 -
The Science of the Total Environment Jan 2024Nanoplastics in environments are potentially detrimental to plant growth. Appropriate doses of biochar can alleviate the phytotoxicity of nanoplastics under hydroponic...
Nanoplastics in environments are potentially detrimental to plant growth. Appropriate doses of biochar can alleviate the phytotoxicity of nanoplastics under hydroponic conditions. However, the specific mechanisms remain unknown. In this study, the effects of biochar-derived dissolved matter (BCDM) and biochar-derived particulate matter (BCPM) on the phytotoxicity of polyvinyl chloride (PVC) nanoplastics were investigated and the underlying influencing mechanisms were elucidated. The results showed that PVC nanoplastics can be adsorbed and taken up by lettuce roots, inducing oxidative damage to lettuce shoots and roots and reducing their fresh weight. BCDM can promote the aggregation and sedimentation of PVC nanoplastics, and BCPM can adsorb PVC nanoplastics and cause barrier effect, which will reduce the exposure dose of PVC nanoplastics. Furthermore, nutrients in BCDM can promote lettuce growth. As a result, the presence of both BCDM and BCPM significantly mitigated the oxidative stress of lettuce shoots and roots as demonstrated by the decrease in hydrogen peroxide and malondialdehyde levels (p < 0.05). Meanwhile, lettuce biomass was significantly increased after addition of BCDM and BCPM compared to the single PVC treatment group (p < 0.05). This study provides a theoretical basis for finding solutions to alleviate the phytotoxicity of nanoplastics.
Topics: Microplastics; Particulate Matter; Polyvinyl Chloride; Charcoal; Lactuca
PubMed: 37741394
DOI: 10.1016/j.scitotenv.2023.167258 -
Scientific Reports Dec 2023Plastic is a fossil-based synthetic polymer that has become an essential material in our daily life. Plastic pollution resulting from the accumulation of plastic objects...
Plastic is a fossil-based synthetic polymer that has become an essential material in our daily life. Plastic pollution resulting from the accumulation of plastic objects has become problematic for our environment. Bioplastic can be a biodegradable environmentally friendly alternative for the synthetic plastic. In this paper, bioplastics based on polyvinyl alcohol (PVA)/gellan gum (GG) blend have been produced in three different compositions and their chemical structure, mechanical, morphological and thermal properties have been studied. Glycerol has been used as a plasticizer. To add extra features to the PVA/GG bioplastic, Psidium guajava (guava) leaves, GL, and chickpea, CP, extracts have been added to the PVA/GG (30/70) blend. Water and aqueous ethanol have been used in the extraction of GL and CP, respectively. The addition of the plant's extracts enhanced the tensile properties of the PVA/GG bioplastic. Weathering acceleration tests have been carried out to examine the degradation of the prepared bioplastics. Cytotoxicity studies revealed that the prepared bioplastic is safe to be used in food packaging applications. Water and oxygen permeability for the new PVA/GG bioplastic have also been studied. The addition of the plant extracts (GL and CP extracts) increased the oxygen and water permeability to different extents. Bioplastic life cycle assessment (LCA) and CO emissions in comparison to fossil-based plastic have been investigated. From all the results, PVA/GG based bioplastic proved to be a degradable, safe and effective alternative for fossil-based plastics in food packaging applications.
Topics: Polyvinyl Alcohol; Food Packaging; Cicer; Psidium; Plastics; Water; Biopolymers; Oxygen
PubMed: 38104220
DOI: 10.1038/s41598-023-49756-0