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1.
World J Gastroenterol ; 30(31): 3680-3688, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39192996

ABSTRACT

BACKGROUND: Commonly used cleaning brushes in the reprocessing of flexible endoscopes often cause damage within the working channels. AIM: To develop a spray flushing system to achieving effective cleaning of the working channels while minimizing damage. METHODS: This prospective study included 60 used endoscopes and 60 Teflon tubes randomly divided into a control group (n = 30) and an experimental group (n = 30). The material of Teflon tubes was the same as that of the endoscope working channel. Endoscopes in the control group were manually cleaned using traditional cleaning brushes, while those in the experimental group were cleaned using the newly developed spray flushing system. ATP levels, cleanliness, and microbiological testing of the working channels were measured. Additionally, Teflon tubes in the control group underwent 500 passes with a cleaning brush, while those in the experimental group were subjected to the spray flushing system, and channel damage was evaluated. RESULTS: The ATP levels (RLU) in the two groups were 32.5 (13-66) and 26 (16-40), respectively (P > 0.05). Cleanliness scores were 1.5 (1-2) and 1 (1-2), respectively (P > 0.05). Debris was found in 73.3% of the control group, which was significantly higher than 46.7% in the experimental group (P < 0.05). Microbiological tests for both groups yielded negative results. Teflon tube damage in the control group was rated at 4 (4-5.25), which was significantly higher than in the experimental group 4 (3-4) (P < 0.01). CONCLUSION: The spray flushing system demonstrated superior efficacy in removing debris and resulted in less damage to the endoscope working channels compared with traditional cleaning brushes.


Subject(s)
Adenosine Triphosphate , Disinfection , Endoscopes , Equipment Contamination , Prospective Studies , Disinfection/methods , Equipment Contamination/prevention & control , Humans , Adenosine Triphosphate/analysis , Adenosine Triphosphate/metabolism , Endoscopes/microbiology , Equipment Reuse/standards , Polytetrafluoroethylene , Endoscopes, Gastrointestinal/microbiology , Equipment Design , Cross Infection/prevention & control
2.
Nanoscale ; 16(31): 14784-14792, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-38990153

ABSTRACT

Self-powered liquid droplet sensors based on triboelectric nanogenerators have attracted extensive attention in the field of biochemical sensing applications. Numerous research studies have investigated the effects of factors such as molecular species, molecular concentration, molecular charge, and molecular dipole moment in solution on the output electrical signals of the sensor. In this study, we prepared a self-powered droplet sensor using conductive copper film tape, polytetrafluoroethylene, and conductive aluminum foil tape. The sensor can continuously output pulsed electrical signals with minimal environmental impact. In comparison with other types of sensors, this sensor boasts a rapid response time of 10 ms and excellent sensitivity. The relationship between the friction-induced output current and voltage of the droplets and the concentration of green tea polyphenols (GTPs) was studied using the self-powered liquid droplet sensor with five different green tea samples. It was found that GTPs were the main factor contributing to the changes in output electrical signals in green tea water droplets. Fluorescence spectroscopy was used to reveal that the magnitude of the output current was inversely proportional to the concentration of GTPs in green tea. These results demonstrate the potential application of self-powered liquid droplet sensors in biochemical sensing applications based on concentration-dependent output signals.


Subject(s)
Polyphenols , Tea , Polyphenols/analysis , Polyphenols/chemistry , Tea/chemistry , Biosensing Techniques , Nanotechnology , Electric Power Supplies , Polytetrafluoroethylene/chemistry , Spectrometry, Fluorescence
3.
J Occup Environ Hyg ; 21(8): 539-550, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38958555

ABSTRACT

Direct-on-Filter (DoF) analysis of respirable crystalline silica (RCS) by Fourier Transform Infrared (FTIR) spectroscopy is a useful tool for assessing exposure risks. With the RCS exposure limits becoming lower, it is important to characterize and reduce measurement uncertainties. This study systematically evaluated two filter types (i.e., polyvinyl chloride [PVC] and polytetrafluoroethylene [PTFE]) for RCS measurements by DoF FTIR spectroscopy, including the filter-to-filter and day-to-day variability of blank filter FTIR reference spectra, particle deposition patterns, filtration efficiencies, and pressure drops. For PVC filters sampled at a flow rate of 2.5 L/min for 8 h, the RCS limit of detection (LOD) was 7.4 µg/m3 when a designated laboratory reference filter was used to correct the absorption by the filter media. When the spectrum of the pre-sample filter (blank filter before dust sampling) was used for correction, the LOD could be up to 5.9 µg/m3. The PVC absorption increased linearly with reference filter mass, providing a means to correct the absorption differences between the pre-sample and reference filters. For PTFE, the LODs were 12 and 1.2 µg/m3 when a designated laboratory blank or the pre-sample filter spectrum was used for blank correction, respectively, indicating that using the pre-sample blank spectrum will reduce RCS quantification uncertainty. Both filter types exhibited a consistent radially symmetric deposition pattern when particles were collected using 3-piece cassettes, indicating that RCS can be quantified from a single measurement at the filter center. The most penetrating aerodynamic diameters were around 0.1 µm with filtration efficiencies ≥ 98.8% across the measured particle size range with low-pressure drops (0.2-0.3 kPa) at a flow rate of 2.5 L/min. This study concludes that either the PVC or the PTFE filters are suitable for RCS analysis by DoF FTIR, but proper methods are needed to account for the variability of blank absorption among different filters.


Subject(s)
Polytetrafluoroethylene , Polyvinyl Chloride , Silicon Dioxide , Spectroscopy, Fourier Transform Infrared/methods , Polyvinyl Chloride/chemistry , Silicon Dioxide/analysis , Silicon Dioxide/chemistry , Polytetrafluoroethylene/chemistry , Filtration/instrumentation , Air Filters , Dust/analysis , Occupational Exposure/analysis , Air Pollutants, Occupational/analysis , Environmental Monitoring/methods , Environmental Monitoring/instrumentation , Limit of Detection , Particle Size , Inhalation Exposure/analysis
4.
Catheter Cardiovasc Interv ; 104(2): 264-271, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38973374

ABSTRACT

Patients with functionally univentricular hearts are usually palliated surgically. There have been several reports of successful attempts to complete the Fontan procedure without surgery. The pathways created at the time of the preconditioning were largely reminiscent of the lateral tunnel Fontan. However, this approach is still confidentially limited to a small number of centers. In 2013, we designed a circuit that mimics the actual surgical technique of extracardiac total cavopulmonary connection to allow for transcatheter completion in an animal study. A polytetrafluoroethylene conduit was connected between the pulmonary artery and the inferior vena cava (IVC). The superior anastomosis was occluded to avoid flow between IVC and superior vena cava (SVC). The conduit was connected to the right atrium (RA) and a large fenestration was created to allow free flow from the IVC to the RA. Extrapolating our approach, a center reported the successful transcatheter completion of an extracardiac Fontan in a 6-year-old child. However, this technique is not directly transposable to our population of patients who require preconditioning in infancy. We report here an innovative extension of this technique that may allow preparing patients in infancy, ideally at the time of the Glenn in the future, to receive an extracardiac Fontan at 2 years/11 kg without additional surgery.


Subject(s)
Cardiac Catheterization , Fontan Procedure , Heart Defects, Congenital , Fontan Procedure/adverse effects , Cardiac Catheterization/instrumentation , Humans , Heart Defects, Congenital/surgery , Heart Defects, Congenital/physiopathology , Heart Defects, Congenital/diagnostic imaging , Pulmonary Artery/surgery , Pulmonary Artery/physiopathology , Pulmonary Artery/diagnostic imaging , Vena Cava, Inferior/diagnostic imaging , Vena Cava, Inferior/surgery , Vena Cava, Inferior/physiopathology , Polytetrafluoroethylene , Univentricular Heart/surgery , Univentricular Heart/physiopathology , Univentricular Heart/diagnostic imaging , Prosthesis Design , Treatment Outcome , Hemodynamics , Animals , Blood Vessel Prosthesis
5.
Chemosphere ; 363: 142814, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38986773

ABSTRACT

There is a lack of agreement on a suitable container material for per- and polyfluoroalkyl substances (PFAS) analysis, particularly at trace levels. In this study, the losses of 18 short- and long-chain (C4-C10) PFAS to commonly used labware materials (high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), polypropylene co-polymer (PPCO), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), and glass were investigated. The influence of sample storage and preparation conditions, i.e., storage time, solvent composition, storage temperatures (4 °C and 20 °C), and sample agitation techniques (shaking and centrifugation) on PFAS losses to the container materials were investigated. The results showed higher losses for most of the considered PFAS (up to 50.9%) in 100% aqueous solutions after storage for 7 days regardless of the storage temperature compared to those after 3 days. Overall, the order of losses to different materials varied for individual PFAS, with the highest losses of long-chain PFAS observed to PP and HDPE after 7-day storage at room temperature. The addition of methanol to aqueous PFAS solutions reduced the losses of long-chain PFAS to all tested materials. The use of sample centrifugation and shaking did not influence the extent of losses for most of the PFAS in 80:20 water:methanol (%, v/v) to container materials except for 8:2 fluorotelomer sulfonic acid (8:2 FTS), 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS), perfluorodecanoic acid (PFDA) and 4:2 fluorotelomer sulfonic acid (4:2 FTS). This study demonstrates lower losses of both long- and short-chain PFAS to glass and PET. It also highlights the need for caution when deciding on sample preparatory steps and storage during the analysis of PFAS.


Subject(s)
Fluorocarbons , Fluorocarbons/analysis , Fluorocarbons/chemistry , Polyethylene Terephthalates/chemistry , Temperature , Polyethylene/chemistry , Polypropylenes/chemistry , Polytetrafluoroethylene/chemistry , Glass/chemistry , Polystyrenes/chemistry
6.
Chemosphere ; 363: 142807, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38992445

ABSTRACT

As trace levels of thallium (Tl) in water are lethal to humans and ecosystems, it is essential to exploit advanced technologies for efficient Tl removal. In response to this concern, an innovative composite membrane was developed, incorporating polytetrafluoroethylene (PTFE) and featuring a dual-support system with polydopamine (PDA) and polyethyleneimine (PEI), along with bimetallic Prussian blue analogues (Co@Fe-PBAs) as co-supports. The composite membrane exhibited an exceptional Tl+-adsorption capacity (qm) of 186.1 mg g-1 when utilized for the treatment of water containing low concentration of Tl+ (0.5 mg⋅L-1). Transmission electron microscopy displayed the obvious Tl+ mapping inside the special hollow Co@Fe-PBAs crystals, demonstrating the deep intercalation of Tl+ via ion exchange and diffusion. The Tl+-adsorption capability of the composite membrane was not greatly affected by coexisting Na+, Ca2+ and Mg2+ as well as the tricky K+, indicating the excellent anti-interference. Co-doped PBAs enhanced ion exchange and intercalation of the composite membrane with Tl+ leading to excellent Tl+ removal efficiency. The composite membrane could efficiently remove Tl+ from thallium-contaminated river water to meet the USEPA standard. This study provides a cost-effective membrane-based solution for efficient Tl+ removal from Tl+-containing wastewater.


Subject(s)
Cobalt , Ferrocyanides , Iron , Thallium , Water Pollutants, Chemical , Ferrocyanides/chemistry , Cobalt/chemistry , Water Pollutants, Chemical/chemistry , Thallium/chemistry , Adsorption , Iron/chemistry , Water Purification/methods , Indoles/chemistry , Polymers/chemistry , Membranes, Artificial , Polytetrafluoroethylene/chemistry , Polyethyleneimine/chemistry
7.
Ren Fail ; 46(2): 2371056, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39011597

ABSTRACT

Currently, three expanded polytetrafluoroethylene (ePTFE) prosthetic graft types are most commonly used for patients with end-stage kidney disease (ESKD) who require long-term vascular access for hemodialysis. However, studies comparing the three ePTFE grafts are limited. This study compared the clinical efficacy and postoperative complications of three ePTFE prosthetic graft types used for upper limb arteriovenous graft (AVG) surgery among patients with ESKD. Patients with ESKD requiring upper limb AVG surgery admitted to our center between January 2016 and September 2019 were enrolled. Overall, 282 patients who completed the 2-year follow-up were included and classified into the following three groups according to the ePTFE graft type: the GPVG group with the PROPATEN® graft, the GAVG group with the straight-type GORE® ACUSEAL, and the BVVG group with the VENAFLO® II. The patency rate and incidence of access-related complications were analyzed and compared between groups. The patients were followed up postoperatively, and data were collected at 6, 12, 18, and 24 months postoperatively. Respective to these follow-up time points, in the GPVG group, the primary patency rates were 74.29%, 65.71%, 51.43%, and 42.86%; the assisted primary patency rates were 85.71%, 74.29%, 60.00%, and 48.57%; and the secondary patency rates were 85.71%, 80.00%, 71.43%, and 60.00%. In the GAVG group, the primary patency rates were 73.03%, 53.93%, 59.42%, and 38.20%; the assisted primary patency rates were 83.15%, 68.54%, 59.55%, and 53.93%; and the secondary patency rates were 85.39%, 77.53%, 68.54%, and 62.92%, respectively. In the BVVG group, the primary patency rates were 67.24%, 53.45%, 41.38%, and 29.31%; the assisted primary patency rates were 84.48%, 67.24%, 55.17%, and 44.83%; and the secondary patency rates were 86.21%, 81.03%, 68.97%, and 60.34%, respectively. The differences in patency rates across the three grafts were not statistically significant. Overall, 18, 4, and 12 patients in the GPVG, GAVG, and BVVG groups, respectively, experienced seroma. Among the three grafts, GORE® ACUSEAL had the shortest anastomosis hemostatic time. The first cannulation times for the three grafts were GPVG at 16 (±8.2), GAVG at 4 (±4.9), and BVVG at 18 (±12.7) days. No significant difference was found in the postoperative swelling rate between the GPVG group and the other two groups. Furthermore, no statistically significant differences were found across the three graft types regarding postoperative vascular access stenosis and thrombosis, ischemic steal syndrome, pseudoaneurysm, or infection. In conclusion, no statistically significant differences in the postoperative primary, assisted primary, or secondary graft patency rates were observed among the three groups. A shorter anastomosis hemostatic time, first cannulation time, and seroma occurrence were observed with the ACUSEAL® graft than with its counterparts. The incidence of upper extremity swelling postoperatively was greater with the PROPATEN® graft than with the other grafts. No statistically significant differences were observed among the three grafts regarding the remaining complications.


Subject(s)
Arteriovenous Shunt, Surgical , Blood Vessel Prosthesis , Kidney Failure, Chronic , Polytetrafluoroethylene , Renal Dialysis , Upper Extremity , Vascular Patency , Humans , Male , Female , Middle Aged , Retrospective Studies , Upper Extremity/blood supply , Blood Vessel Prosthesis/adverse effects , Aged , Arteriovenous Shunt, Surgical/adverse effects , Arteriovenous Shunt, Surgical/methods , Kidney Failure, Chronic/therapy , Blood Vessel Prosthesis Implantation/adverse effects , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis Implantation/methods , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Prosthesis Design , Adult , Treatment Outcome , Graft Occlusion, Vascular/etiology , Graft Occlusion, Vascular/epidemiology
8.
Clin Exp Dent Res ; 10(4): e902, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39014549

ABSTRACT

OBJECTIVES: Guided bone regeneration (GBR) is a core procedure used to regenerate bone defects. The aim of the study was to investigate the adherence of Candida albicans on six commercially available polytetrafluoroethylene (PTFE) membranes used in GBR procedures and the subsequent clinical consequences. MATERIALS AND METHODS: Six commercially available PTFE membranes were tested. Two of the membranes had a textured surface and the other four a plane, nontextured one. C. albicans (ATCC 24433) was cultured for 24 h, and its cell surface hydrophobicity was assessed using a modified method. C. albicans adhesion to membrane discs was studied by scanning electron microscopy (SEM) and real-time polymerase chain reaction (PCR). RESULTS: C. albicans was found to be hydrophobic (77.25%). SEM analysis showed that C. albicans adherence to all membranes examined was characterized by patchy, scattered, and small clustered patterns except for one nontextured membrane with a most rough surface in which a thick biofilm was observed. Real-time PCR quantification revealed significantly greater adhesion of C. albicans cells to PTFE membranes than the control membrane (p ≤ .001) with the membranes having a textured surface exhibiting the highest count of 2680 × 104 cells/ml compared to the count of 707 × 104 cells/mL on those with a nontextured one (p ≤ .001). One membrane with nontextured surface, but with most rough surface was found to exhibit the highest count of 3010 × 104 cells/ml (p ≤ .05). CONCLUSION: The results of this study indicate that C. albicans adhesion on membranes' surfaces depends on the degree of surface roughness and/or on the presence of a texture. Textured PTFE membranes and/or membranes high roughness showed significantly more adhered C. albicans cells. These findings can impact the surgeon's choice of GBR membrane and postoperative maintenance.


Subject(s)
Bone Regeneration , Candida albicans , Membranes, Artificial , Microscopy, Electron, Scanning , Polytetrafluoroethylene , Candida albicans/physiology , Polytetrafluoroethylene/chemistry , Biofilms/growth & development , Cell Adhesion , Humans , Real-Time Polymerase Chain Reaction , Hydrophobic and Hydrophilic Interactions , Surface Properties , Guided Tissue Regeneration/methods , Guided Tissue Regeneration/instrumentation
9.
Catheter Cardiovasc Interv ; 104(2): 247-251, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38860616

ABSTRACT

In the absence of standardized management guidelines, coronary artery aneurysms (CAAs) present therapeutic challenges. Percutaneous coronary intervention (PCI) is rarely explored, especially in giant aneurysms with persistent angina, where surgery might be presumed as a preferred option. We describe the technical aspects and feasibility of PCI using Gore Viabahn expanded polytetrafluoroethylene (ePTFE)-covered nitinol self-expanding stents in a 66-year-old woman with a complex medical history and an enlarging, symptomatic right coronary artery aneurysm. The case was complicated by endoleak after the first stent, but intravascular ultrasound guidance enabled the precise deployment of additional stents, resulting in the successful exclusion of the aneurysm. This case demonstrates steps to successful CAA PCI with Gore Viabahn ePTFE-covered nitinol self-expanding stents and emphasizes that in unsuitable surgical candidates, PCI might be a potential alternative for symptomatic CAAs.


Subject(s)
Alloys , Coronary Aneurysm , Prosthesis Design , Ultrasonography, Interventional , Humans , Coronary Aneurysm/diagnostic imaging , Coronary Aneurysm/surgery , Coronary Aneurysm/therapy , Aged , Female , Treatment Outcome , Self Expandable Metallic Stents , Coronary Angiography , Polytetrafluoroethylene , Percutaneous Coronary Intervention/instrumentation , Stents , Angioplasty, Balloon, Coronary/instrumentation
10.
Clin Oral Investig ; 28(7): 373, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874776

ABSTRACT

AIM: This study evaluated the impact of the partial exposition of the nonabsorbable membrane (dPTFE) on microbial colonization during bone healing. MATERIALS AND METHODS: Patients indicated for tooth extraction were randomized to dPTFE group (n = 22) - tooth extraction and alveolar ridge preservation (ARP) using an intentionally exposed dPTFE membrane and USH group (n = 22) - tooth extraction and unassisted socket healing. Biofilm samples were collected at the barrier in the dPTFE and on the natural healing site in the USH after 3 and 28 days. Samples from the inner surface of the dPTFE barrier were also collected (n = 13). The microbiome was evaluated using the Illumina MiSeq system. RESULTS: Beta diversity was different from 3 to 28 days in both groups, and at 28 days, different microbial communities were identified between therapies. The dPTFE was characterized by a higher prevalence and abundance of gram-negative and anaerobic species than USH. Furthermore, the inner surface of the dPTFE membrane was colonized by a different community than the one observed on the outer surface. CONCLUSION: Intentionally exposed dPTFE membrane modulates microbial colonization in the ARP site, creating a more homogeneous and anaerobic community on the inner and outer surfaces of the membrane. CLINICAL RELEVANCE: DPTFE promoted faster biofilm colonization and enrichment of gram-negative and anaerobes close to the regenerated site in the membrane's inner and outer surfaces. dPTFE membrane can be used exposed to the oral site, but approaches for biofilm control should still be considered. The study was retrospectively registered at Clinicaltrials.gov (NCT04329351).


Subject(s)
Biofilms , Membranes, Artificial , Tooth Extraction , Humans , Male , Female , Middle Aged , Wound Healing , Adult , Microbiota , Polytetrafluoroethylene , Aged , Tooth Socket/surgery , Tooth Socket/microbiology
11.
Environ Sci Technol ; 58(26): 11606-11614, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38874561

ABSTRACT

Global atmospheric emissions of perfluorocyclobutane (c-C4F8, PFC-318), a potent greenhouse gas, have increased rapidly in recent years. Combining atmospheric observations made at nine Chinese sites with a Lagrangian dispersion model-based Bayesian inversion technique, we show that PFC-318 emissions in China grew by approximately 70% from 2011 to 2020, rising from 0.65 (0.54-0.72) Gg year-1 in 2011 to 1.12 (1.05-1.19) Gg year-1 in 2020. The PFC-318 emission increase from China played a substantial role in the overall increase in global emissions during the study period, contributing 58% to the global total emission increase. This growth predominantly originated in eastern China. The regions with high emissions of PFC-318 in China overlap with areas densely populated with polytetrafluoroethylene (PTFE) factories, implying that fluoropolymer factories are important sources of PFC-318 emissions in China. Our investigation reveals an emission factor of approximately 3.02 g of byproduct PFC-318 emissions per kg of hydrochlorofluorocarbon-22 (HCFC-22) feedstock use in the production of tetrafluoroethylene (TFE) (for PTFE production) and hexafluoropropylene (HFP) if we assume all HCFC-22 produced for feedstock uses in China are pyrolyzed to produce PTFE and HFP. Further facility-level sampling and analysis are needed for a more precise evaluation of emissions from these factories.


Subject(s)
Air Pollutants , Atmosphere , China , Air Pollutants/analysis , Atmosphere/chemistry , Environmental Monitoring , Fluorocarbons/analysis , Bayes Theorem , Polytetrafluoroethylene , Cyclobutanes
12.
Environ Sci Pollut Res Int ; 31(27): 39663-39677, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38831146

ABSTRACT

The mixed wastewater generated by anodic oxidation coating facilities contains high levels of various contaminants, including iron, aluminum, conductivity, chemical oxygen demand (COD), and sulfate. In this study, the effectiveness of the membrane distillation (MD) process using polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) membranes was investigated to treat mixed wastewater from an anodized coating factory. The results indicate that both hydrophobic membranes effectively removed targeted contaminants. However, the PTFE membrane achieved higher removal efficiencies, with over 99% removal of sulfate, conductivity, iron, and aluminum, 85.7% of COD, and 86% of total organic carbon (TOC). In contrast, the PVDF membrane exhibited a significant decline in removal efficiency as the temperature increased and performed well only at lower feed temperatures. The PTFE membranes outperformed the PVDF membranes in treating chemically intensive anodic oxidation wastewaters. This superiority can be attributed to the PTFE membrane's morphology and structure, which are less influenced by feed water temperature and chemicals. Additionally, its slippery surface imparts anti-adhesion properties, effectively preventing membrane fouling, and maintaining the treated water quality and flux for longer operation time.


Subject(s)
Distillation , Membranes, Artificial , Oxidation-Reduction , Polytetrafluoroethylene , Polyvinyls , Wastewater , Wastewater/chemistry , Polytetrafluoroethylene/chemistry , Polyvinyls/chemistry , Waste Disposal, Fluid/methods , Water Purification/methods , Water Pollutants, Chemical , Fluorocarbon Polymers
13.
Aquat Toxicol ; 272: 106967, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38833998

ABSTRACT

Microplastics (MPs) are ubiquitous in aquatic environments, which can act as carriers to affect the bioavailability of heavy metals. The aging process in the environment changes the physicochemical properties of MPs, thereby affecting their environmental behavior and co-toxicity with other pollutants. However, relevant research is limited. In this study, we compared the properties and Cu2+ adsorption capacity of pristine and aged polytetrafluoroethylene (PTFE) MPs and further explored the influence on copper bioavailability and bio-effects on Microcystis aeruginosa. Aging process induced surface oxidation and cracks of PTFE MPs, and decreased the stability of MPs in water by increasing zeta potential. PTFE MPs had a strong adsorption capacity for Cu2+ and increased the bioavailability of copper to microalgae, which was not affected by the aging process. Pristine and aged PTFE MPs adhered to cyanobacterium surfaces and caused shrinkage and deformation of cells. Inhibition of cyanobacterium growth, photosynthesis and reduction of total antioxidant capacity were observed in the treatment of PTFE MPs. Combined exposure of pristine MPs and Cu2+ had stronger toxic effects to cyanobacterium, and increased Microcystin-LR release, which could cause harm to aquatic environment. Aging reduced the toxic effects of PTFE MPs on microalgae. Furthermore, soluble exopolysaccharide (EPS) content was significantly higher in co-exposure of aged MPs and Cu2+, which could reduce the toxicity to cyanobacterium cells. These results indicate that aging process alleviates the toxicity to microalgae and environmental risks caused by PTFE MPs. This study improves understanding of the combined toxicity of aged MPs and metals in freshwater ecosystems.


Subject(s)
Biological Availability , Copper , Microcystis , Microplastics , Polytetrafluoroethylene , Water Pollutants, Chemical , Microcystis/drug effects , Copper/toxicity , Water Pollutants, Chemical/toxicity , Microplastics/toxicity , Polytetrafluoroethylene/chemistry , Polytetrafluoroethylene/toxicity , Ultraviolet Rays , Adsorption , Microalgae/drug effects
14.
J Surg Res ; 300: 352-362, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38843722

ABSTRACT

INTRODUCTION: This study aims to assess the association of operative time with the postoperative length of stay and unplanned return to the operating room in patients undergoing femoral to below knee popliteal bypasses, stratified by autologous vein graft or polytetrafluoroethylene (PTFE). MATERIALS AND METHODS: A retrospective analysis of vascular quality initiative database (2003-2021). The selected patients were grouped into the following: vein bypass (group I) and PTFE (group II) patients. Each group was further stratified by a median split of operative time (i.e., 210 min for autologous vein and 155 min for PTFE) to study the outcomes. The outcomes were assessed by univariate and multivariate approach. RESULTS: Of the 10,902 patients studied, 3570 (32.7%) were in the autologous vein group, while 7332 (67.3%) were in the PTFE group. Univariate analysis revealed autologous vein and PTFE graft recipients that had increased operative times were associated with a longer mean postoperative length of stay and a higher incidence of all-cause return to the operating room. In PTFE group, patients with prolonged operative times were also found to be associated with higher incidence of major amputation, surgical site infection, and cardiovascular events, along with loss of primary patency within a year. CONCLUSIONS: For patients undergoing femoral to below knee popliteal bypasses using an autologous vein or PTFE, longer operative times were associated with inferior outcomes. Mortality was not found to be associated with prolonged operative time.


Subject(s)
Length of Stay , Lower Extremity , Operative Time , Polytetrafluoroethylene , Humans , Retrospective Studies , Male , Female , Middle Aged , Aged , Lower Extremity/surgery , Lower Extremity/blood supply , Length of Stay/statistics & numerical data , Treatment Outcome , Peripheral Arterial Disease/surgery , Peripheral Arterial Disease/mortality , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Blood Vessel Prosthesis Implantation/adverse effects , Blood Vessel Prosthesis Implantation/methods , Blood Vessel Prosthesis Implantation/mortality , Veins/transplantation , Veins/surgery , Vascular Grafting/methods , Vascular Grafting/statistics & numerical data , Vascular Grafting/adverse effects , Vascular Grafting/mortality
15.
Cell Rep Methods ; 4(6): 100796, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38866007

ABSTRACT

We present an efficient, effective, and economical approach, named E3technology, for proteomics sample preparation. By immobilizing silica microparticles into the polytetrafluoroethylene matrix, we develop a robust membrane medium, which could serve as a reliable platform to generate proteomics-friendly samples in a rapid and low-cost fashion. We benchmark its performance using different formats and demonstrate them with a variety of sample types of varied complexity, quantity, and volume. Our data suggest that E3technology provides proteome-wide identification and quantitation performance equivalent or superior to many existing methods. We further propose an enhanced single-vessel approach, named E4technology, which performs on-filter in-cell digestion with minimal sample loss and high sensitivity, enabling low-input and low-cell proteomics. Lastly, we utilized the above technologies to investigate RNA-binding proteins and profile the intact bacterial cell proteome.


Subject(s)
Proteome , Proteomics , Proteomics/methods , Proteome/analysis , Proteome/metabolism , Silicon Dioxide/chemistry , Polytetrafluoroethylene
16.
Langmuir ; 40(27): 13810-13818, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38918081

ABSTRACT

The friction of solids is primarily understood through the adhesive interactions between the surfaces. As a result, slick materials tend to be nonstick (e.g., Teflon), and sticky materials tend to produce high friction (e.g., tires and tape). Paradoxically, cartilage, the slippery bearing material of human joints, is also among the stickiest of known materials. This study aims to elucidate this apparent paradox. Cartilage is a biphasic material, and the most cited explanation is that both friction and adhesion increase as load transfers from the pressurized interstitial fluid to the solid matrix over time. In other words, cartilage is slippery and sticky under different times and conditions. This study challenges this explanation, demonstrating the strong adhesion of cartilage under high and low interstitial hydration conditions. Additionally, we find that cartilage clings to itself (a porous material) and Teflon (a nonstick material), as well as other surfaces. We conclude that the unusually strong interfacial tension produced by cartilage reflects suction (like a clingfish) rather than adhesion (like a gecko). This finding is surprising given its unusually large roughness, which typically allows for easy interfacial flow and defeats suction. The results provide compelling evidence that cartilage, like a clingfish, conforms to opposing surfaces and effectively seals submerged contacts. Further, we argue that interfacial sealing is itself a critical function, enabling cartilage to retain hydration, load support, and lubrication across long periods of inactivity.


Subject(s)
Cartilage, Articular , Cartilage, Articular/chemistry , Animals , Friction , Lubrication , Surface Properties , Adhesiveness , Polytetrafluoroethylene/chemistry
17.
J Oral Implantol ; 50(3): 141-152, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38839071

ABSTRACT

After dental extraction, a physiological phenomenon of reabsorption of the dentoalveolar process is triggered, especially if periradicular lesions are present, which can sometimes be associated with oroantral communication in the upper posterior maxilla. To investigate a minimally invasive approach, 19 patients undergoing tooth extraction in the posterosuperior maxilla were recruited. All cases presented an oroantral communication with a diameter of 2-5 mm after tooth extraction and the alveolar process and, in some cases, with a partial defect of 1 or more bony walls. In these cases, a single surgical procedure was used to preserve the alveolar ridge using an open barrier technique with an exposed dense polytetrafluoroethylene membrane. The bottom of the extraction socket was filled with a collagen fleece. The residual bone process was reconstructed using a biomaterial based on carbonate-apatite derived from porcine cancellous bone. After 6 months, all patients were recalled and subjected to radiographic control associated with an implant-prosthetic rehabilitation plan. Data relating to the sinus health status and the average height and thickness of the regenerated bone were collected. Radiographic evaluation verified the integrity of the maxillary sinus floor with new bone formation, detecting a vertical bone dimension between 3.1 mm and 7.4 mm (average 5.13 ± 1.15 mm) and a horizontal thickness between 4.2 mm and 9.6 mm (average 6.86 ± 1.55 mm). The goal of this study was to highlight the advantage of managing an oroantral communication and, simultaneously, obtain the preservation and regeneration of the alveolar bone crest. The open barrier technique appears to be effective for the minimally invasive management of oroantral communication up to 5 mm in diameter in postextraction sites, with a good regeneration of hard and soft tissue.


Subject(s)
Membranes, Artificial , Oroantral Fistula , Polytetrafluoroethylene , Tooth Extraction , Humans , Retrospective Studies , Oroantral Fistula/surgery , Middle Aged , Male , Female , Alveolar Process/surgery , Alveolar Process/diagnostic imaging , Tooth Socket/surgery , Aged , Adult , Maxilla/surgery , Bone Regeneration/physiology , Alveolar Ridge Augmentation/methods , Collagen/therapeutic use
18.
Ann Vasc Surg ; 106: 273-283, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38821469

ABSTRACT

BACKGROUND: The heparin-bonded expanded polytetrafluoroethylene (He-ePTFE) conduit is an option for patients requiring infrainguinal revascularization (iIR), but the risk of failure may be unpredictable, especially in cases with poor run-off. Intraoperative transit-time flow (TTF) provides an automated and quantitative analysis of flow and may serve as an adjunct evaluation during surgical revascularization. The aim of this study was to assess TTF in patients undergoing iIR with He-PTFE at 3 referral hospitals and to establish a predictive flow threshold for graft occlusion. METHODS: A prospective registry initiated in 2020 enrolled patients undergoing iIR using He-PTFE for critical limb ischemia or severe claudication, and TTF measurement was analyzed. Preoperative assessments of anatomical and clinical characteristics were available for all patients. The HT353 Optima Meter (Transonic Systems Inc., Ithaca, NY, USA) was used in all procedures according to a standardized protocol. The institutional ethics committee approved the study. A predictive model using receiver operating characteristic curve analysis was utilized to establish the threshold of flow, and variables were compared. Anatomical and clinical evaluation were reported according to Rutherford grade, Global Limb Anatomic System and Wound, Ischemia, and foot Infection classification. The main outcome considered was the correlation between TTF and graft occlusion. Secondary outcomes included survival, other predictors of graft occlusion, freedom from major adverse cardiovascular events, and freedom from major amputation. RESULTS: Among 68 patients, 55.8% had Rutherford 5-6, 45.6% had Global Limb Anatomic System 3 and 73.5% had Wound, Ischemia, and foot Infection 3-4. Distal anastomosis was at tibial level in 23.5% and mean diameter of conduit was 6.4 mm. Basal and postoperative TTF were 27.8 ± 15.6 ml/min and 109.0 ± 53.0 ml/min, respectively. After a mean follow-up of 18 ± 13 months, 7 (10.9%) patients presented graft occlusion and 5 (7.8%) required major amputation. TTF threshold = 80 ml/min revealed a sensitivity and specificity of 81.8% (95% confidence interval 48.2-97.7) and 80.7% (95% confidence interval 68.1-90.0) respectively, and it was selected as cut-off for graft occlusion. Freedom from graft occlusion in patients with TTF >80 ml/min vs. TTF ≤80 ml/min at 6, 12, and 24 months was 95.7% (standard error (SE) = 0.030) vs. 65.5% (SE = 0.115), 95.7% (SE = 0.030) vs. 58.9% (SE = 0.120) and 90.9% (SE = 0.054) vs. 51.6% (SE = 0.126), P = 0.0003. No statistical difference in primary patency, secondary patency and limb salvage was observed. At multivariate analysis, distal anastomosis at tibial vessel (odds ratio 8.50) and TTF ≤80 ml/min (odds ratio 9.39) were independent predictors of graft occlusion. CONCLUSIONS: These results suggest that TTF may serve as a valuable tool in the management of iIR. A TTF measurement of ≤80 ml/min should be regarded as a predictor of graft occlusion, prompting consideration of additional intraoperative maneuvers to enhance arterial flow. Caution should be exercised in patients requiring direct tibial artery revascularization, as it represents a predictor of failure independent of TTF levels. Larger cohorts of patients and longer follow-up periods are necessary to confirm these findings.


Subject(s)
Blood Vessel Prosthesis Implantation , Blood Vessel Prosthesis , Graft Occlusion, Vascular , Heparin , Ischemia , Peripheral Arterial Disease , Polytetrafluoroethylene , Predictive Value of Tests , Prosthesis Design , Regional Blood Flow , Registries , Vascular Patency , Humans , Male , Female , Aged , Prospective Studies , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis Implantation/adverse effects , Heparin/administration & dosage , Heparin/adverse effects , Peripheral Arterial Disease/physiopathology , Peripheral Arterial Disease/surgery , Peripheral Arterial Disease/diagnostic imaging , Time Factors , Risk Factors , Graft Occlusion, Vascular/etiology , Graft Occlusion, Vascular/physiopathology , Ischemia/physiopathology , Ischemia/surgery , Ischemia/diagnosis , Ischemia/diagnostic imaging , Middle Aged , Aged, 80 and over , Blood Flow Velocity , Coated Materials, Biocompatible , Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Critical Illness , Limb Salvage , Treatment Failure , Amputation, Surgical , Risk Assessment , Intermittent Claudication/physiopathology , Intermittent Claudication/surgery , Intermittent Claudication/diagnostic imaging , Intermittent Claudication/diagnosis
19.
Acta Neurochir (Wien) ; 166(1): 239, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38814504

ABSTRACT

BACKGROUND: Microvascular conflicts in hemifacial spasm typically occur at the facial nerve's root exit zone. While a pure microsurgical approach offers only limited orientation, added endoscopy enhances visibility of the relevant structures without the necessity of cerebellar retraction. METHODS: After a retrosigmoid craniotomy, a microsurgical decompression of the facial nerve is performed with a Teflon bridge. Endoscopic inspection prior and after decompression facilitates optimal Teflon bridge positioning. CONCLUSIONS: Endoscope-assisted microsurgery allows a clear visualization and safe manipulation on the facial nerve at its root exit zone.


Subject(s)
Hemifacial Spasm , Microvascular Decompression Surgery , Polytetrafluoroethylene , Humans , Hemifacial Spasm/surgery , Microvascular Decompression Surgery/methods , Facial Nerve/surgery , Craniotomy/methods , Endoscopy/methods , Neuroendoscopy/methods , Microsurgery/methods , Female , Middle Aged , Male
20.
PLoS One ; 19(5): e0303931, 2024.
Article in English | MEDLINE | ID: mdl-38820420

ABSTRACT

Spray drying fruit juice powders poses challenges because sugars and organic acids with low molecular weight and a low glass transition temperature inherently cause stickiness. This study employed a hydrophobic polytetrafluoroethylene (PTFE) film to mimic the surface of the drying chamber wall. The Central Composite Design (CCD) using response surface methodology investigated the impact of power (X1, Watt) and the duration of oxygenated plasma treatment (X2, minutes) on substrate contact angle (°), reflecting surface hydrophobicity. To validate the approach, Morinda citrofolia (MC) juice, augmented with maltodextrins as drying agents, underwent spray drying on the improved PTFE-coated surface. The spray drying process for MC juice was performed at inlet air temperatures of 120, 140, and 160°C, along with Noni juice-to-maltodextrin solids ratios of 4.00, 1.00, and 0.25. The PTFE-coated borosilicate substrate, prepared at a radio frequency (RF) power of 90W for 15 minutes of treatment time, exhibited a porous and spongy microstructure, correlating with superior contact angle performance (171°) compared to untreated borosilicate glass. Optimization data indicated that the PTFE film attained an optimum contact angle of 146.0° with a specific combination of plasma RF operating power (X1 = 74 W) and treatment duration (X2 = 10.0 minutes). RAMAN spectroscopy indicated a structural analysis with an ID/IG ratio of 0.2, while Brunauer-Emmett-Teller (BET) surface area analysis suggested an average particle size of less than 100 nm for all coated films. The process significantly improved the powder's hygroscopicity, resistance to caking, and moisture content of maltodextrin-MC juice. Therefore, the discovery of this modification, which applies oxygen plasma treatment to PTFE-coated substrates, effectively enhances surface hydrophobicity, contact angle, porosity, roughness, and ultimately improves the efficacy and recovery of the spray drying process.


Subject(s)
Polytetrafluoroethylene , Polytetrafluoroethylene/chemistry , Surface Properties , Food Handling/methods , Oxygen/chemistry , Fruit and Vegetable Juices , Hydrophobic and Hydrophilic Interactions , Polysaccharides/chemistry , Plasma Gases/chemistry
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