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Scientific Reports Jul 2023Gutta-percha's lack of adhesion has been presented as a drawback to avoid gaps at sealer/gutta-percha interface. Plasma treatments have been scarcely assessed on...
Gutta-percha's lack of adhesion has been presented as a drawback to avoid gaps at sealer/gutta-percha interface. Plasma treatments have been scarcely assessed on gutta-percha surfaces as a method of enhancing adhesiveness. This study aimed to evaluate the effect of low-pressure Argon and Oxygen plasma atmospheres on conventional and bioceramic gutta-percha standardized smooth discs, assessing their roughness, surface free energy, chemical structure, and sealer wettability. A Low-Pressure Plasma Cleaner by Diener Electronic (Zepto Model) was used. Different gases (Argon or Oxygen), powers (25 W, or 50 W), and exposure times (30 s, 60 s, 120 s, or 180 s) were tested in control and experimental groups. Kruskal-Wallis and Student's t-test were used in data analysis. Statistically significant differences were detected when P < 0.05. Both gases showed different behaviors according to the parameters selected. Even though chemical changes were detected, the basic molecular structure was maintained. Argon or Oxygen plasma treatments favoured the wetting of conventional and bioceramic gutta-perchas by Endoresin and AH Plus Bioceramic sealers (P < 0.001). Overall, the functionalization of gutta-percha surfaces with Argon or Oxygen plasma treatments can increase roughness, surface free energy and wettability, which might improve its adhesive properties when compared to non-treated gutta-percha.
Topics: Humans; Adhesiveness; Argon; Gutta-Percha; Gases; Oxygen
PubMed: 37516768
DOI: 10.1038/s41598-023-37372-x -
Cancers Apr 2023Medical use of (non-)thermal plasmas is an emerging field in gynaecology. However, data on plasma energy dispersion remain limited. This systematic review presents an... (Review)
Review
Medical use of (non-)thermal plasmas is an emerging field in gynaecology. However, data on plasma energy dispersion remain limited. This systematic review presents an overview of plasma devices, fields of effective application, and impact of use factors and device settings on tissues in the female pelvis, including the uterus, ovaries, cervix, vagina, vulva, colon, omentum, mesenterium, and peritoneum. A search of the literature was performed on 4 January 2023 in the Medline Ovid, Embase, Cochrane, Web of Science, and Google Scholar databases. Devices were classified as plasma-assisted electrosurgery (ES) using electrothermal energy, neutral argon plasma (NAP) using kinetic particle energy, or cold atmospheric plasma (CAP) using non-thermal biochemical reactions. In total, 8958 articles were identified, of which 310 were scanned, and 14 were included due to containing quantitative data on depths or volumes of tissues reached. Plasma-assisted ES devices produce a thermal effects depth of <2.4 mm. In turn, NAP effects remained superficial, <1.0 mm. So far, the depth and uniformity of CAP effects are insufficiently understood. These data are crucial to achieve complete treatment, reduce recurrence, and limit damage to healthy tissues (e.g., prevent perforations or preserve parenchyma). Upcoming and potentially high-gain applications are discussed, and deficits in current evidence are identified.
PubMed: 37190314
DOI: 10.3390/cancers15082386 -
Brazilian Dental Journal 2022To evaluate the flexural strength (FS) and flexural modulus (FM) of a commercial 3Y-TZ0P ceramic after artificial aging and either without or with two application times...
To evaluate the flexural strength (FS) and flexural modulus (FM) of a commercial 3Y-TZ0P ceramic after artificial aging and either without or with two application times of non-thermal plasma treatments (NTP). In addition, changes in crystalline phase transformation and surface nano-topography after NTP application, during different aging periods, were evaluated. Ninety 3Y-TZP bars (45x4x3 mm) were made for FS and FM testing, and assigned to nine groups (n=10): no NTP/no aging (Control); no NTP/4h aging; no NTP/30h aging; 10s NTP/no aging; 10s NTP/4h aging; 10s NTP/30h aging; 60s NTP/no aging; 60s NTP/4h aging and 60s NTP/30h aging. Artificial accelerated aging was simulated using an autoclave (134º C at 2 bar) for up to 30h. FS and FM were assessed using a universal testing machine and data analyzed using a ANOVA and Tukey test (α=0.05). The volume change in zirconia monoclinic phase (MPV) was evaluated using X-ray diffraction and surface nano-topography was assessed using atomic force microscopy (baseline until 30h-aging). NTP application did not influence the FS and FM of zirconia. Compared to the Control (no NTP/no aging), the FS of zirconia samples treated for 30 hours in autoclave ("no NTP/30h aging" group) increased. Artificial aging for 30 hours significantly increased the FM of zirconia, regardless of NTP application. MPV tended to increase following the increase in aging time, which might result in the surface irregularities observed at 30h-aging. NTP did not alter the zirconia properties tested, but 30h-aging can change the zirconia FS, FM and MPV.
Topics: Plasma Gases; Dental Materials; Argon; Materials Testing; Surface Properties; Zirconium; Ceramics; Yttrium
PubMed: 36287491
DOI: 10.1590/0103-6440202204849 -
Medicine Sep 2022Intentional or unintentional exposure to asphyxiating gases is a significant public health concern worldwide. Argon poisoning is fatal, and its onset is primarily due to...
RATIONALE
Intentional or unintentional exposure to asphyxiating gases is a significant public health concern worldwide. Argon poisoning is fatal, and its onset is primarily due to neurological damage.
PATIENT CONCERNS
A 22-year-old man was admitted to the hospital for argon gas poisoning. While working in a plant containing argon gas, he suddenly lost consciousness, recovered consciousness slightly after on-site treatment, answered questions, and had impaired memory, sensory dullness, normal cognition, and symptoms of dizziness and headache.
DIAGNOSIS
Asphyxiating gas poisoning (argon gas poisoning), metabolic encephalopathy, and hepatic insufficiency.
INTERVENTIONS
Immediately after admission, the patient was treated with nasal cannula oxygen 3 L/min and hyperbaric oxygen therapy once a day. Mecobalamin tablets 500 μg were given orally 3 times a day. Oral Ginkgo biloba extract tablets 40 mg 3 times a day.
OUTCOME
The patient was discharged after treatment with hyperbaric oxygen therapy and nerve-nourishing drugs, with no discomfort, clear consciousness, and good memory, and was followed up by telephone for 2 consecutive months, and the patient is now in good condition with no discomfort.
LESSON
This case describes the pathogenesis, neurological damage, and rescue process of argon gas poisoning. Argon poisoning was found to damage bilateral cerebellar hemispheres and bilateral hippocampal regions, affecting the patient's consciousness and memory, and was found to cause abnormal liver function and heart rate disorders.
Topics: Adult; Argon; Carbon Monoxide Poisoning; Gas Poisoning; Humans; Hyperbaric Oxygenation; Male; Oxygen; Young Adult
PubMed: 36086783
DOI: 10.1097/MD.0000000000030491 -
Materials (Basel, Switzerland) Jan 2022Various approaches are being pursued to physico-chemically modify the zirconia neck region of dental implants to improve the integration into the surrounding soft...
Various approaches are being pursued to physico-chemically modify the zirconia neck region of dental implants to improve the integration into the surrounding soft tissue. In this study, polished zirconia discs were laser microstructured with periodic cavities and convex waves. These zirconia samples were additionally activated by argon plasma using the kINPen09. The surface topography was characterized by scanning electron microscopy and the surface wettability by water contact angle. The in vitro study with human gingival fibroblasts (HGF-1) was focused on cell spreading, morphology, and actin cytoskeleton organization within the first 24 h. The laser-induced microstructures were originally hydrophobic (e.g., 60 µm cavities 138.4°), but after argon plasma activation, the surfaces switched to the hydrophilic state (60 µm cavities 13.7°). HGF-1 cells adhered flatly on the polished zirconia. Spreading is hampered on cavity structures, and cells avoid the holes. However, cells on laser-induced waves spread well. Interestingly, argon plasma activation for only 1 min promoted adhesion and spreading of HGF-1 cells even after 2 h cultivation. The cells crawl and grow into the depth of the cavities. Thus, a combination of both laser microstructuring and argon plasma activation of zirconia seems to be optimal for a strong gingival cell attachment.
PubMed: 35160678
DOI: 10.3390/ma15030732 -
Annals of Cardiac Anaesthesia 2019
Topics: Argon
PubMed: 30971590
DOI: 10.4103/aca.ACA_180_18 -
PloS One 2015Recently, the noble gas argon attracted significant attention due to its neuroprotective properties. However, the underlying molecular mechanism is still poorly...
PURPOSE
Recently, the noble gas argon attracted significant attention due to its neuroprotective properties. However, the underlying molecular mechanism is still poorly understood. There is growing evidence that the extracellular regulated kinase 1/2 (ERK1/2) is involved in Argon´s protective effect. We hypothesized that argon mediates its protective effects via the upstream located toll-like receptors (TLRs) 2 and 4.
METHODS
Apoptosis in a human neuroblastoma cell line (SH-SY5Y) was induced using rotenone. Argon treatment was performed after induction of apoptosis with different concentrations (25, 50 and 75 Vol% in oxygen 21 Vol%, carbon dioxide and nitrogen) for 2 or 4 hours respectively. Apoptosis was analyzed using flow cytometry (annexin-V (AV)/propidiumiodide (PI)) staining, caspase-3 activity and caspase cleavage. TLR density on the cells' surface was analyzed using FACS and immunohistochemistry. Inhibition of TLR signaling and extracellular regulated kinase 1/2 (ERK1/2) were assessed by western blot, activity assays and FACS analysis.
RESULTS
Argon 75 Vol% treatment abolished rotenone-induced apoptosis. This effect was attenuated dose- and time-dependently. Argon treatment was accompanied with a significant reduction of TLR2 and TLR4 receptor density and protein expression. Moreover, argon mediated increase in ERK1/2 phosphorylation was attenuated after inhibition of TLR signaling. ERK1/2 and TLR signaling inhibitors abolished the anti-apoptotic and cytoprotective effects of argon. Immunohistochemistry results strengthened these findings.
CONCLUSION
These findings suggest that argon-mediated anti-apoptotic and neuroprotective effects are mediated via inhibition of TLR2 and TLR4.
Topics: Apoptosis; Argon; Caspase 3; Cell Line, Tumor; Humans; MAP Kinase Signaling System; Neuroblastoma; Neuroprotection; Neuroprotective Agents; Phosphorylation; Rotenone; Signal Transduction; Toll-Like Receptor 2; Toll-Like Receptor 4
PubMed: 26624894
DOI: 10.1371/journal.pone.0143887 -
World Journal of Gastroenterology May 2020Radiofrequency ablation (RFA) is very effective for eradication of flat Barrett's mucosa in dysplastic Barrett's esophagus after endoscopic resection of raised lesions.... (Review)
Review
Radiofrequency ablation (RFA) is very effective for eradication of flat Barrett's mucosa in dysplastic Barrett's esophagus after endoscopic resection of raised lesions. However, in a minority of the time, RFA may be ineffective at eradication of the Barrett's mucosa. Achieving complete eradication of intestinal metaplasia can be challenging in these patients. This review article focuses on the management of patients with dysplastic Barrett's esophagus refractory to RFA therapy. Management strategies discussed in this review include optimizing the RFA procedure, optimizing acid suppression (with medical, endoscopic, and surgical management), cryotherapy, hybrid argon plasma coagulation, and EndoRotor resection.
Topics: Antacids; Argon Plasma Coagulation; Barrett Esophagus; Combined Modality Therapy; Cryosurgery; Esophageal Neoplasms; Esophagoscopy; Esophagus; Gastroesophageal Reflux; Humans; Radiofrequency Ablation; Treatment Outcome
PubMed: 32536772
DOI: 10.3748/wjg.v26.i17.2030 -
Journal of Cellular and Molecular... Oct 2022We investigated the effects of lacking TNFα on the development and regression of Argon-laser-induced choroidal neovascularization (CNV) in mice. We lasered ocular...
We investigated the effects of lacking TNFα on the development and regression of Argon-laser-induced choroidal neovascularization (CNV) in mice. We lasered ocular fundus for induction of CNV in both wild-type (WT) and TNFα-null (KO) mice. Fluorescence angiography was performed to examine the size of CNV lesions. Gene expression pattern of wound healing-related components was examined. The effects of exogenous TNFα on apoptosis of human retinal microvascular endothelial cells (HRMECs) and on the tube-like structure of the cells were investigated in vitro. The results showed that Argon-laser irradiation-induced CNV was significantly larger in KO mice than WT mice on Day 21, but not at other timepoints. Lacking TNFα increased neutrophil population in the lesion. The distribution of cleaved caspase3-labelled apoptotic cells was more frequently observed in the laser-irradiated tissue in a WT mouse as compared with a KO mouse. Exogenous TNFα induced apoptosis of HRMECs and accelerated regression of tube-like structure of HRMECs in cell culture. Taken together, TNFα gene knockout delays the regression of laser-induced CNV in mice. The mechanism underlying the phenotype might include the augmentation of neutrophil population in the treated tissue and attenuation of vascular endothelial cell apoptosis.
Topics: Animals; Argon; Choroidal Neovascularization; Disease Models, Animal; Endothelial Cells; Humans; Lasers; Mice; Mice, Inbred C57BL; Mice, Knockout; Tumor Necrosis Factor-alpha
PubMed: 36127870
DOI: 10.1111/jcmm.17562 -
Membranes Jan 2021In the present study, we developed a novel approach for functionalization of gelatin nanofibers using the plasma method for tissue engineering applications. For this...
In the present study, we developed a novel approach for functionalization of gelatin nanofibers using the plasma method for tissue engineering applications. For this purpose, tannic acid-crosslinked gelatin nanofibers were fabricated with electrospinning, followed by treatment with argon and argon-oxygen plasmas in a vacuum chamber. Samples were evaluated by using scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, contact angle (CA) and X-ray diffraction (XRD). The biological activity of plasma treated gelatin nanofibers were further investigated by using fibroblasts as cell models. SEM studies showed that the average diameter and the surface morphology of nanofibers did not change after plasma treatment. However, the mean surface roughness (RMS) of samples were increased due to plasma activation. ATR-FTIR spectroscopy demonstrated several new bands on plasma treated fibers related to the plasma ionization of nanofibers. The CA test results stated that the surface of nanofibers became completely hydrophilic after argon-oxygen plasma treatment. Finally, increasing the polarity of crosslinked gelatin after plasma treatment resulted in an increase of the number of fibroblast cells. Overall, results expressed that our developed method could open new insights into the application of the plasma process for functionalization of biomedical scaffolds. Moreover, the cooperative interplay between gelatin biomaterials and argon/argon-oxygen plasmas discovered a key composition showing promising biocompatibility towards biological cells. Therefore, we strongly recommend plasma surface modification of nanofiber scaffolds as a pretreatment process for tissue engineering applications.
PubMed: 33401681
DOI: 10.3390/membranes11010031