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Materials (Basel, Switzerland) Nov 2023Titanium thin films are particularly important as electrode layers, barrier layers, or intermediate buffer layers in the semiconductor industry. In order to improve the...
Titanium thin films are particularly important as electrode layers, barrier layers, or intermediate buffer layers in the semiconductor industry. In order to improve the quality of Ti thin films and the adhesion and diffraction abilities of irregular parts, this paper used high-power pulsed magnetron sputtering (HPPMS/HiPIMS) to prepare titanium thin films. The effects of different trigger voltages (700 V, 800 V, and 900 V) on plasma properties were studied, and the microstructure, mechanical properties and corrosion resistance of the films were also studied. The results showed that as the voltage increased, the grain size of the thin films gradually increased. The residual stress of the titanium films changed from compressive stress (-333 MPa) to tensile stress (55 MPa) and then to low compressive stress (-178 MPa). The hardness values were 13 GPa, 9.45 GPa and 6.62 GPa, respectively. The wear resistance of the films gradually decreased, while the toughness gradually increased. The corrosion resistance of the films decreased as well.
PubMed: 38068038
DOI: 10.3390/ma16237294 -
Journal of Hazardous Materials Mar 2024Poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride (PHMB) is a biocide with a broad spectrum of antibacterial activity. Its use as a disinfectant and...
Assessment of poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride-induced developmental neurotoxicity via oxidative stress mechanism: Integrative approaches with neuronal cells and zebrafish.
Poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride (PHMB) is a biocide with a broad spectrum of antibacterial activity. Its use as a disinfectant and preservative in consumer products results in human exposure to PHMB. Toxicity studies on PHMB mainly focus on systemic toxicity or skin irritation; however, its effects on developmental neurotoxicity (DNT) and the underlying mechanisms are poorly understood. In this study, the DNT effects of PHMB were evaluated using IMR-32 and SH-SY5Y cell lines and zebrafish. In both cell lines, PHMB concentrations ≥ 10 µM reduced neurite outgrowth, and cytotoxicity was observed at concentrations up to 40 µM. PHMB regulated expression of neurodevelopmental genes and induced reactive oxygen species (ROS) production and mitochondrial dysfunction. Treatment with N-acetylcysteine reversed the toxic effects of PHMB. Toxicity tests on zebrafish embryos showed that PHMB reduced viability and heart rate and caused irregular hatching. PHMB concentrations of 1-4 µM reduced the width of the brain and spinal cord of transgenic zebrafish and attenuated myelination processes. Furthermore, PHMB modulated expression of neurodevelopmental genes in zebrafish and induced ROS accumulation. These results suggested that PHMB exerted DNT effects in vitro and in vivo through a ROS-dependent mechanism, highlighting the risk of PHMB exposure.
Topics: Animals; Humans; Reactive Oxygen Species; Zebrafish; Neuroblastoma; Oxidative Stress; Disinfectants; Embryo, Nonmammalian; Diamines
PubMed: 38064952
DOI: 10.1016/j.jhazmat.2023.133146 -
Cureus Nov 2023Atrial fibrillation (AFib) is one of the most prevalent irregular heartbeats that doctors encounter. Clinicians typically pursue two main approaches for treatment,... (Review)
Review
Atrial fibrillation (AFib) is one of the most prevalent irregular heartbeats that doctors encounter. Clinicians typically pursue two main approaches for treatment, namely, controlling the heart rate and managing the heart rhythm. Under the rhythm control approach, AFib is addressed through cardioversion, which is achieved either with medications termed pharmacological cardioversion (PCV) or via an electrical shock termed electric cardioversion (ECV). While ECV proves instrumental in AFib management, it carries its own risk factors, potentially leading to blood clot-related complications such as embolic strokes. To counteract this potential downside, a well-established strategy involves the utilization of transesophageal echocardiography (TEE) to identify possible embolic sources before initiating cardioversion. The goal of this systematic review is to highlight the role of TEE in preempting embolic occurrences following ECV during the management of AFib. After conducting a thorough search of databases, namely, PubMed, PubMed Central, and Medline, a total of 36 studies were selected for this review article. Following a comprehensive evaluation of these studies, it was concluded that TEE plays a pivotal role in preventing thromboembolic complications during ECV for AFib. However, it is important to note that further research is needed to delve deeper into this matter. While existing evidence underscores its efficacy, additional investigation is needed to address this subject matter comprehensively.
PubMed: 38046740
DOI: 10.7759/cureus.48149 -
Journal of the American Society of... Apr 2024Transesophageal echocardiography (TEE) can reliably detect left atrial (LA) and LA appendage (LAA) thrombus in patients with atrial fibrillation (AF) before electrical...
BACKGROUND
Transesophageal echocardiography (TEE) can reliably detect left atrial (LA) and LA appendage (LAA) thrombus in patients with atrial fibrillation (AF) before electrical cardioversion (ECV). However, evaluating cardiac and valve function pre-ECV can be challenging due to the increased and irregular heart rate. Additionally, post-ECV atrial stunning increases the risk of LAA thrombosis. Therefore, post-ECV TEE may allow for useful appendage, ventricular, and valve function assessment. However, the safety and usefulness of leaving the TEE probe in situ during ECV for post-ECV cardiac evaluation in clinical practice have not been previously evaluated.
METHODS
We analyzed 37 out of 86 consecutive patients who had the TEE probe left in situ, for clinical reasons, during ECV by a single operator between February 20, 2019, and January 3, 2023. We examined changes in left ventricular (LV) function, dynamic changes in valvular regurgitation, electromechanical coupling of the left atrium, and qualitative spontaneous echo contrast. We also assessed the presence of any complications related to the periprocedural TEE exam.
RESULTS
The mean age of the patients was 74 ± 9.65 years, and 29 (78%) were male. The periprocedural TEE time ranged from 7 to 55 minutes, with an average of 20.78 minutes. Immediately after ECV and restoration of normal sinus rhythm, there was an improvement in LV ejection fraction (47% ± 11.9% vs 40% ± 15.8%; P = .035). There was also a reduction in baseline mitral regurgitation of greater than moderate degree. However, spontaneous echo contrast worsened in the LAA in 11 (31.4%) patients. Additionally, 1 patient developed a new LAA thrombus, and 24 patients (72%) had evidence of electromechanical coupling with Doppler evidence of LA contraction. Clinically significant degenerative aortic and mitral stenosis were identified in 8% and mild or greater aortic regurgitation in 8% of patients post-ECV. No procedural complications were observed.
CONCLUSIONS
In situ TEE before, during, and after ECV is safe and provides useful clinical information regarding immediate cardiac changes after ECV, with diagnostic and therapeutic implications.
Topics: Humans; Male; Middle Aged; Aged; Aged, 80 and over; Female; Echocardiography, Transesophageal; Atrial Fibrillation; Electric Countershock; Echocardiography; Atrial Appendage; Thrombosis
PubMed: 38036012
DOI: 10.1016/j.echo.2023.11.022 -
Ultrasound in Obstetrics & Gynecology :... May 2024Fetal premature atrial contractions (PAC) are usually benign but may be associated with congenital heart defect (CHD) and tachyarrhythmia, which in turn carry a risk of...
OBJECTIVES
Fetal premature atrial contractions (PAC) are usually benign but may be associated with congenital heart defect (CHD) and tachyarrhythmia, which in turn carry a risk of cardiac failure and fetal death. We aimed to explore the frequency of adverse outcome and to identify risk factors for tachyarrhythmia in pregnancies complicated by fetal PAC.
METHODS
This was a retrospective cohort study of fetuses diagnosed with PAC at two academic centers in Amsterdam, The Netherlands, between 2007 and 2022. Cases with a congenital anomaly and those with a prior diagnosis of CHD or other arrhythmias were excluded. M-mode and Doppler tracings were reanalyzed and the frequency of PAC was recorded. The incidence of the following adverse outcomes was examined: underlying CHD not identified at the 20-week fetal anomaly scan, tachyarrhythmia, other arrhythmia, administration of antiarrhythmic therapy and death. Risk factors for tachyarrhythmia were analyzed using odds ratios (OR).
RESULTS
In 24.1% of 1439 referred cases, PAC resolved before confirmation at the fetal medicine unit (FMU). Of the 939 included cases with confirmed PAC, the total incidence of adverse outcome was 6.8% (64/939). CHD was diagnosed in 14 (1.5% (95% CI, 0.9-2.5%)) cases, of which eight were diagnosed prenatally and six postnatally. Compared with baseline, the incidence of CHD was higher in the presence of fetal PAC (OR, 1.8 (95% CI, 1.0-3.3); P = 0.034). Tachyarrhythmia occurred prenatally and/or postnatally in 32 (3.4%) cases, of which eight (25.0%) showed signs of cardiac failure, and in 23 (71.9%) cases, antiarrhythmic therapy was required. No cases of tachyarrhythmia led to fetal or infant death. Risk factors for tachyarrhythmia were PAC with short runs of supraventricular tachycardia (OR, 98.7), blocked PAC (OR, 30.3), PAC in bigeminy (OR, 21.8), frequent PAC (one per 5-10 beats) (OR, 6.9), signs of cardiac failure (OR, 14.2) and the presence of a foramen ovale aneurysm (OR, 5.0).
CONCLUSIONS
PAC are generally benign and often resolve spontaneously. However, fetuses with an irregular heart rhythm should be referred for advanced ultrasonography, which should focus on classifying the type of PAC and risk of adverse outcome. When risk factors for tachyarrhythmia are identified, weekly fetal heart-rate monitoring is advised until resolution of the PAC. In the absence of risk factors, standard obstetric care may be sufficient, with additional instructions to report reduced fetal movements. Should tachyarrhythmia or cardiac failure develop, referral back to the FMU is indicated. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Topics: Humans; Female; Pregnancy; Retrospective Studies; Risk Factors; Netherlands; Atrial Premature Complexes; Tachycardia; Heart Defects, Congenital; Ultrasonography, Prenatal; Adult; Incidence; Pregnancy Outcome; Fetal Death; Gestational Age
PubMed: 38030959
DOI: 10.1002/uog.27546 -
Scars, Burns & Healing 2023Hypertrophic scarring is a common and debilitating consequence of burn scars. While there is limited evidence for current treatment options, laser therapy has been shown...
INTRODUCTION
Hypertrophic scarring is a common and debilitating consequence of burn scars. While there is limited evidence for current treatment options, laser therapy has been shown to be effective, low risk and minimally invasive. This study assesses the use of carbon dioxide lasers and intense pulsed light devices in the treatment of hypertrophic burn scars.
METHODS
In this case series, patients were recruited from a hypertrophic burn scar waitlist and completed a Patient and Observer Scar Assessment Scale prior to and six weeks after laser therapy. The Nordlys (intense pulsed light) and CORE (carbon dioxide) systems from Candela Medical were used, with a range of settings used depending on the assessment of the burn scar. The differences between scores were calculated for the total Patient and Observer Scar Assessment Scale score, pain, itch, colour, stiffness, thickness, irregularity and the overall opinion of the scar. Statistical analysis was completed using a paired, two-tailed student T test.
RESULTS
A total of 31 patients were recruited for this trial with a range of scar locations, surface areas and mechanism of burn injury. The calculated difference in mean showed a significant reduction for the overall Patient and Observer Scar Assessment Scale score (1.93, p < 0.0001), pain (1.39, p = 0.0002), itch (1.84, p = 0.0002), colour (1.97, p < 0.0001), stiffness (2.47, p < 0.0001), thickness (2.1, p < 0.0001), irregularity (1.89, p < 0.0001) and overall opinion (1.58, p = 0.0003).
CONCLUSION
Current management options for hypertrophic scarring have limited evidence. Laser therapy presents a minimally invasive procedure that can be completed under topical anaesthetic and has shown to be effective following a single treatment of combined carbon dioxide laser and intense pulsed light device therapy.
LAY SUMMARY
Many people will suffer a burn injury throughout their life and up to almost 3 out of 4 people with burn injuries will suffer from hypertrophic scars (a thickened, red and itchy scar). These scars cause distress both due to their appearance and their reduction of function, particularly over a joint or muscle. Laser therapy, in which different wave lengths of light (pulsed light) or gas (carbon dioxide) target the scar, has been found to be effective and have minimal side effects in the management of hypertrophic scars. While individual lasers have been assessed and found to be effective and low risk, the combined use of multiple lasers on the same scar has not been extensively studied. We studied the effectiveness of both light and gas laser therapies on hypertrophic scars. Patients with hypertrophic scars completed a questionnaire that focused on their perspective of their scar (pain, itch, stiffness, thickness, irregularity, overall opinion) prior to the treatment. The patients then underwent laser therapy (with local anaesthetic gel) with either pulsed light and/or carbon dioxide (gas) laser. The type of laser used was decided by the clinician performing the therapy depending on scar location and thickness. Patients then re-completed the subjective survey six weeks following the laser therapy, and the results compared. We learnt that laser therapy (both light, gas and a combination of both) are effective (and low risk) in reducing the subjective burden of the scar for the patient.
PubMed: 38022893
DOI: 10.1177/20595131231202103 -
Scientific Reports Nov 2023A medical check-up during driving enables the early detection of diseases. Heartbeat irregularities indicate possible cardiovascular diseases, which can be determined...
A medical check-up during driving enables the early detection of diseases. Heartbeat irregularities indicate possible cardiovascular diseases, which can be determined with continuous health monitoring. Therefore, we develop a redundant sensor system based on electrocardiography (ECG) and photoplethysmography (PPG) sensors attached to the steering wheel, a red, green, and blue (RGB) camera behind the steering wheel. For the video, we integrate the face recognition engine SeetaFace to detect landmarks of face segments continuously. Based on the green channel, we derive colour changes and, subsequently, the heartbeat. We record the ECG, PPG, video, and reference ECG with body electrodes of 19 volunteers during different driving scenarios, each lasting 15 min: city, highway, and countryside. We combine early, signal-based late, and sensor-based late fusion with a hybrid convolutional neural network (CNN) and integrated majority voting to deliver the final heartbeats that we compare to the reference ECG. Based on the measured and the reference heartbeat positions, the usable time was 51.75%, 58.62%, and 55.96% for the driving scenarios city, highway, and countryside, respectively, with the hybrid algorithm and combination of ECG and PPG. In conclusion, the findings suggest that approximately half the driving time can be utilised for in-vehicle heartbeat monitoring.
Topics: Humans; Heart Rate; Signal Processing, Computer-Assisted; Electrocardiography; Algorithms; Neural Networks, Computer; Photoplethysmography
PubMed: 38012195
DOI: 10.1038/s41598-023-47484-z -
Sensors (Basel, Switzerland) Nov 2023Smartwatches equipped with automatic atrial fibrillation (AF) detection through electrocardiogram (ECG) recording are increasingly prevalent. We have recently reported...
Smartwatches equipped with automatic atrial fibrillation (AF) detection through electrocardiogram (ECG) recording are increasingly prevalent. We have recently reported the limitations of the Apple Watch (AW) in correctly diagnosing AF. In this study, we aim to apply a data science approach to a large dataset of smartwatch ECGs in order to deliver an improved algorithm. We included 723 patients (579 patients for algorithm development and 144 patients for validation) who underwent ECG recording with an AW and a 12-lead ECG (21% had AF and 24% had no ECG abnormalities). Similar to the existing algorithm, we first screened for AF by detecting irregularities in ventricular intervals. However, as opposed to the existing algorithm, we included all ECGs (not applying quality or heart rate exclusion criteria) but we excluded ECGs in which we identified regular patterns within the irregular rhythms by screening for interval clusters. This "irregularly irregular" approach resulted in a significant improvement in accuracy compared to the existing AW algorithm (sensitivity of 90% versus 83%, specificity of 92% versus 79%, < 0.01). Identifying regularity within irregular rhythms is an accurate yet inclusive method to detect AF using a smartwatch ECG.
Topics: Humans; Atrial Fibrillation; Electrocardiography; Heart Rate; Algorithms
PubMed: 38005669
DOI: 10.3390/s23229283 -
Journal of Neurophysiology Dec 2023Rett syndrome (RTT) is a severe neurodevelopmental disorder that mainly affects females due to silencing mutations in the X-linked gene. One of the most troubling...
Rett syndrome (RTT) is a severe neurodevelopmental disorder that mainly affects females due to silencing mutations in the X-linked gene. One of the most troubling symptoms of RTT is breathing irregularity, including apneas, breath-holds, and hyperventilation. Mice with silencing mutations in exhibit breathing abnormalities similar to human patients and serve as useful models for studying mechanisms underlying breathing problems in RTT. Previous work implicated the pontine, respiratory-controlling Kölliker-Fuse (KF) in the breathing problems in RTT. The goal of this study was to test the hypothesis that inhibitory synaptic transmission is deficient in KF neurons from symptomatic male and female RTT mice. We performed whole cell voltage-clamp recordings from KF neurons in acute brain slices to examine spontaneous and electrically evoked inhibitory post-synaptic currents (IPSCs) in RTT mice and age- and sex-matched wild-type mice. The frequency of spontaneous IPSCs was reduced in KF neurons from male RTT mice but surprisingly not in female RTT mice. In addition, electrically evoked IPSCs were less reliable in KF neurons from male, but not female, RTT mice, which was positively correlated with paired-pulse facilitation, indicating decreased probability of release. KF neurons from male RTT mice were also more excitable and exhibited shorter-duration action potentials. Increased excitability of KF neurons from male mice was not explained by changes in axon initial segment length. These findings indicate impaired inhibitory neurotransmission and increased excitability of KF neurons in male but not female RTT mice and suggest that sex-dependent mechanisms contribute to breathing problems in RTT. Kölliker-Fuse (KF) neurons in acute brain slices from male Rett syndrome (RTT) mice receive reduced inhibitory synaptic inputs compared with wild-type littermates. In female RTT mice, inhibitory transmission was not different in KF neurons compared with controls. The results from this study show that sex-specific alterations in synaptic transmission occur in the KF of RTT mice.
Topics: Humans; Male; Mice; Animals; Female; Rett Syndrome; Methyl-CpG-Binding Protein 2; Synaptic Transmission; Neurons; Respiration; Pons; Disease Models, Animal
PubMed: 37965930
DOI: 10.1152/jn.00327.2023 -
Journal of Stomatology, Oral and... Jun 2024Laser application for the treatment of peri‑implantitis provides a variety of advantages; however, depending on the laser type and parameters, it may also have adverse...
The effects of diode and Er:YAG laser applications on the surface topography of titanium grade 4 and titanium zirconium discs with sand-blasted and acid-etched (SLA) surfaces.
BACKGROUND
Laser application for the treatment of peri‑implantitis provides a variety of advantages; however, depending on the laser type and parameters, it may also have adverse effects on the implant surface qualities. This study's objective is to assess the effects of laser type and parameters on the surface properties of two different titanium-based implant materials: titanium Grade 4 (Ti-Grade 4) and titanium zirconium (Ti-Zr) discs with sand-blasted and acid-etched (SLA) surfaces under in vitro conditions.
MATERIAL & METHOD
Sand-blasted and acid-etched discs made of titanium grade 4 (Ti-Grade 4) and titanium zirconium (Ti-Zr) were treated using 808 nm AlGaAs (diode) and 2940 nm Er:YAG lasers with varying parameters (i.e., diode laser in continuous wave mode, Er:YAG in short pulse mode, and Er:YAG in variable square pulse mode with four different doses). Then, the surface morphology and topography of the treated discs were characterized using scanning electron microscopy and optical profilometry.
RESULTS
The 3D surface topographies of discs treated with a high power Er:YAG laser displayed irregular peaks and deep valleys, indicating surface deterioration. The average surface roughness values (Sa) of both discs varied with laser type and parameters (3.55-4.80 µm for Ti-Grade 4 versus 3.25-4.5 µm for Ti-Zr). With diode laser applications, the topography features of the discs were preserved despite a small number of irregular valleys and peaks. However, the surface morphologies of the discs were dramatically altered by erosion and local melting because of the Er:YAG laser treatment.
CONCLUSION
Diode laser application appears to be the most reliable method for treating peri‑implantitis, as diode laser-treated implants retained their overall surface quality despite a small number of irregular peaks and valleys.
Topics: Titanium; Surface Properties; Zirconium; Lasers, Solid-State; Microscopy, Electron, Scanning; Acid Etching, Dental; Lasers, Semiconductor; Dental Implants; Materials Testing; Dental Etching
PubMed: 37951501
DOI: 10.1016/j.jormas.2023.101680