Acid Exposure Research Articles

Transoral Incisionless Fundoplication Leads to Esophageal Mucosa Healing in Responder Patients Followed up to 2 Years, as Documented by Esophageal Mean Nocturnal Baseline Impedance.

Decrease of esophageal mean nocturnal baseline impedance reflects loss of mucosal integrity. It can predict response to anti-reflux therapy. Mean nocturnal baseline impedance after transoral incisionless fundoplication for gastroesophageal reflux disease has never been assessed. The aim of the study is to investigate mean nocturnal baseline impedance and conventional pathophysiological parameters following transoral incisionless fundoplication. Patients prospectively treated by transoral incisionless fundoplication in a single center were retrospectively reviewed regarding 1- and 2-year 24-hour pH-metry and multichannel intraluminal impedance with calculation of mean nocturnal baseline impedance, gastroesophageal reflux disease-health related quality of life and reflux symptom index scores. Thirty-eight and 17/38 patients with 1- and 2-year 24-hour pH-multichannel intraluminal impedance assessment and mean nocturnal baseline impedance's calculation after transoral incisionless fundoplication, respectively, were identified. Mean nocturnal baseline impedance significantly increased up to 2-year follow-up (P = 0.033), along with significant decrease in % of acid exposure time (P = 0.003), gastroesophageal reflux disease-health related quality of life score (P < 0.001), and reflux symptom index (P = 0.008), compared with baseline. The longest orthostatic reflux decreased too, approaching statistical significance (P = 0.054). These significant changes occurred in patients experiencing ≥ 50% reduction of symptom questionnaires' scores ("responders"). Conversely, mean nocturnal baseline impedance worsened and no significant changes of 24-hour pH-multichannel intraluminal impedance metrics were observed in "non-responder" patients (symptom questionnaires' scores decrease < 50%).ConclusionIn patients who responded a significant improvement of mean nocturnal baseline impedance and % acid exposure time was observed up to 2-year follow-up, suggesting that transoral incisionless fundoplication achieves an effective esophageal mucosa healing besides symptom improvement.

Clinical and laboratory evaluation of the effectiveness of children's toothpastes containing 1000 ppm fluoride

Relevance. This article presents the findings from studies evaluating the effectiveness of toothpastes containing 1000 ppm fluoride in clinical settings. The data demonstrates the cumulative benefits of these toothpastes on oral hygiene, the reduction of inflammatory oral manifestations, and their anticaries effects.Purpose. To assess the effectiveness of fluoride-containing toothpastes through laboratory tests and clinical trials.Materials and methods. The study evaluated the effectiveness of toothpastes containing 1000 ppm fluoride using the following parameters: Greene-Vermillion hygiene index, periodontal indices (PMA and SBI), enamel mineralization and resistance, presence and number of carious lesions at the white spot stage, enamel hypersensitivity, and antimicrobial activity against Streptococcus spp.Results. The analysis of hygiene indices demonstrated that the tested toothpastes were highly effective in cleaning, with a positive cumulative effect on participants' oral hygiene. The use of these toothpastes significantly reduced inflammatory manifestations, decreased gum bleeding, and improved periodontal tissue health. A reduction in the number of participants with early-stage carious lesions, as well as a decrease in the overall number of lesions, was observed. The toothpastes also enhanced enamel resistance to acid exposure, contributing to their anticaries benefits. Enamel hypersensitivity was reduced, and a dose-dependent antibacterial effect against Streptococcus mutans, Streptococcus gordonii, and Streptococcus sobrinus was observed.Conclusion. Toothpastes containing 1000 ppm fluoride demonstrated strong cleaning and refreshing effects, along with a positive cumulative impact on oral hygiene and a significant reduction in inflammation. Their anticaries benefits were confirmed, and they also reduced enamel hypersensitivity. The tested toothpastes were well-tolerated, with no reports of allergic reactions or irritation.

Usefulness of monitoring mycophenolic acid exposure in systemic sclerosis-related interstitial lung disease: a retrospective cohort study

BackgroundSystemic sclerosis-related interstitial lung disease (SSc-ILD) represents a significant cause of morbidity and mortality in Systemic Sclerosis (SSc). Mycophenolate mofetil (MMF) is currently the first line treatment for SSc-ILD. There is no recommendation on the dosage of mycophenolic acid (MPA) blood concentrations, so we aimed to study the correlation between MPA exposure and respiratory outcomes in this population.MethodsWe conducted a retrospective cohort study of SSc-ILD patients treated with MMF in our center. According to our policy, a complete patient evaluation was performed approximately one year after MMF initiation, during which the mycophenolic acid (MPA) residual rate (RR) was measured. We analyzed the association between RR and changes in forced vital capacity (FVC) and diffusion capacity for carbon monoxide (DLCO) over time.ResultsForty-three SSc-ILD patients were included. Patients with higher RR levels (≥ 1.5 mg/L) had a significantly better FVC evolution with a higher proportion of stabilization and lower proportion of FVC decrease (p = 0.024). RR above 1.5 mg/L was a predictive factor of reduced FVC decline compared with lower RR levels adjusting for MMF dose and duration of MMF exposure (p = 0.008). There was no difference regarding DLCO outcome.ConclusionOur study suggests that optimal MPA exposure, as indicated by RR levels, may better protect against FVC decline in SSc-ILD patients treated with MMF. Routine monitoring of MPA exposure could be beneficial in optimizing treatment outcomes. Prospective, multicenter studies are needed to further explore the relationship between MPA exposure and clinical outcomes in SSc-ILD.

Acidic/abrasive challenges on simulated non-carious cervical lesions development and morphology

This in vitro investigation assessed how frequency of erosive challenges and duration of toothbrushing abrasion influenced non-carious cervical lesions (NCCLs) development and morphology. Experimental units were prepared using extracted human premolars assigned to four erosive-abrasive frequency protocols (n=16): F0. No acid exposure (negative control), F2.5 K. Acid exposure (1 % citric acid at natural pH) every 2500, F5K. 5000 and F15K. 15000 brushing-strokes. All groups were brushed for 55000 total brushing-strokes. Three-dimension images of the teeth were captured at baseline, after 15000, 35000 and 55000 brushing-strokes, using an intraoral scanner (TRIOS4, 3Shape). WearCompare software (Leeds Digital Dentistry) was used to analyze volumetric tooth loss (mm3) by superimposition followed by subtraction analysis. Lesion angle was measured (ImageJ, NIH) and morphology visually classified. Data were analyzed using ANOVA and Fisher's Exact tests adopting two-sided 5 % significance level. Tooth loss increased with brushing-strokes overall (p<0.001) and for each erosive-abrasive protocol (p<0.001). Acid exposure significantly increased tooth loss (p<0.001), regardless of brushing interval (p<0.001), however by 35000 strokes no tooth loss difference was observed among acid-exposed groups (p>0.05). Control had significantly sharper mean lesion angle (59°) than all acid-exposed groups (∼145°) (p<0.001), and significantly different lesion shape with 94 % wedge-shaped lesions versus 0 %, respectively (p<0.001). In contrast to the control, acid exposure was associated to more striated lesions. Simulated NCCLs developed and progressed differently and more rapidly in the presence of acidic challenges, regardless of their frequency. Exposure to acid impacted the morphology of lesions.

Bolus exposure as a novel predictor of postoperative symptom resolution after laparoscopic nissen fundoplication: A two-institutional retrospective cohort study.

Even in the absence of definite evidence of pathological acid reflux, antireflux surgery (ARS) can still effectively improve gastroesophageal reflux symptoms. Nonetheless, predicting postoperative reflux symptom improvement has been primarily dependent on acid-based parameters. No objective index reflecting both acid and non-acid reflux was identified to select ARS candidates. Prospectively collected data of 121 patients with gastroesophageal reflux disease (GERD), who underwent laparoscopic Nissen fundoplication from two institutions, were retrospectively reviewed. The patients reported preoperative and postoperative GERD symptoms using the Korean version of the GERD questionnaire, along with the gastroesophageal reflux disease-health-related quality of life (GERD-HRQL). The patients assessed for reflux symptoms using bolus exposure, acid exposure time (AET), and DeMeester score (DMS) as measurements were selected. For each reflux parameter, its association, correlation, and predictive capacity of the degree of postoperative symptom resolution were analyzed using chi-squared tests, point-biserial correlations, logistic regression analyses, and receiver operating characteristic curve analyses. 72 patients were eligible for this study. Bolus exposure was superior to the other parameters in terms of the degree of association and correlation with resolution of typical symptoms. Bolus exposure also showed a higher diagnostic accuracy in predicting the resolution of epigastric pain (area under the curve [AUC]=0.723, P=0.013) and regurgitation (AUC=0.981, P<0.001). Secondary analyses were performed in patients without pathological reflux, defined as the DMS-negative (DMS<14.7) or AET-negative (AET<6%) groups. In the secondary analyses, bolus exposure showed considerable diagnostic accuracy with statistical significance for all typical symptoms in both in the DMS-negative (heartburn: AUC=0.717, P=0.025; epigastric pain: AUC=0.717, P=0.025; regurgitation: AUC=0.975, P<0.001) and AET-negative (heartburn: AUC=0.681, P=0.045; epigastric pain: AUC=0.749, P=0.009; regurgitation: AUC=0.975, P<0.001) groups. Bolus exposure, a parameter of total reflux, was superior to AET or DMS in defining candidates for ARS. Further studies investigating the surgical indications for ARS in patients with non-acid reflux using bolus exposure are required.

Safety of the reduced fixed dose of mycophenolate mofetil confirmed via therapeutic drug monitoring in de novo kidney transplant recipients.

Mycophenolate mofetil (MMF) is usually prescribed with a reduced fixed dose in Asian kidney transplant recipients (KTRs). However, the clinical efficacy and safety of the fixed dose have not yet been investigated via therapeutic drug monitoring. We evaluated whether reduced fixed-dose MMF is an optimal dosing strategy to achieve the therapeutic target of mycophenolic acid (MPA) exposure in Korean KTRs. This open-label, prospective study enrolled 50 de novo KTRs prescribed with tacrolimus, corticosteroid, and fixed-dose MMF (1.0-1.5 g/day). The trough level (C0) and area under the curve (AUC0-12 hr) of MPA were measured at 1 and 24 weeks after kidney transplantation (KT). The relationship of body weight (BW)-adjusted MMF dose with MPA C0 and MPA AUC0-12 hr was assessed using linear regression analysis. The initial fixed dose of MMF of 1.44 ± 0.16 g/day was adjusted in 24 patients (48.0%) and then reduced to a mean dose of 1.19 ± 0.31 g/day at 24 weeks after KT. Most patients (≥84.0%) attained the minimum required MPA C0 of 1.0 μg/mL and MPA AUC0-12 hr of 30 μg × hr/mL at 1 and 24 weeks. The BW-adjusted MMF dose demonstrated significant positive correlations with MPA C0 and MPA AUC0-12 hr at 1 and 24 weeks after KT. Moreover, 14 patients (28.0%) reported MPA-related adverse events that were predictable based on MPA AUC0-12 hr (cutoff level, 46.4 μg × hr/mL). The current reduced fixed-dose MMF strategy can help achieve the therapeutic target of MPA exposure in tacrolimus-treated Korean KTRs during the early posttransplant period.

Comparison of daytime and nighttime supine gastroesophageal reflux by pH monitoring of individuals with clinical suspicion of gastroesophageal reflux disease.

This study aims to compare pHmetric characteristics of diurnal and nocturnal supine reflux. We studied 500 consecutive individuals with clinical suspicion of gastroesophageal reflux disease (GERD) who underwent esophageal high-resolution manometry and prolonged ambulatory pH monitoring. Patients were classified with supine GERD pattern when the percentage of acid reflux time in the supine position was equal to or greater than 2.2%. Data on acid reflux in the supine position during daytime and nighttime recumbency were: (i) acid exposure time, (ii) number of reflux episodes, (iii) longest reflux episode, (iv) interval between the last meal and the supine position, (v) interval between the supine position and the first acid reflux episode, and (vi) reported symptoms. Of the 500 evaluated patients, 238 (48%) had GERD. Among these, supine pattern was observed in 134 (56%) patients, bipositional in 53 (23%), and orthostatic in 51 (21%). In patients with daytime recumbency, 112 (51% of 217) were pathological refluxers, with a mean DeMeester score of 45 ± 26. Total acid exposure time (P = 0.8) and reported Symptom Index (P = 0.2) did not differ depending on the period, whether diurnal or nocturnal. All other pHmetric parameters were lower during daytime recumbency. In conclusion, diurnal supine reflux has similar acid exposure time and temporal correlation between symptoms and reflux episodes as nocturnal supine reflux. Other pHmetric parameters are lower for diurnal supine reflux.

Dental erosion and its correlation with bulimia nervosa: a literature review

Dental erosion is the loss of mineralized tooth tissue caused by acids not originating from the oral microbiota. It results from extrinsic factors, such as acidic foods and beverages, or intrinsic factors, such as gastroesophageal reflux and frequent vomiting. Bulimia nervosa (BN), an eating disorder characterized by episodes of binge eating followed by compensatory behaviors such as forced vomiting, can exacerbate dental erosion. The aim of this study was to conduct a narrative literature review on dental erosion, addressing diagnosis, prevention, treatment, and its correlation with BN. A search was conducted on the PubMed platform in July 2023 using MeSH terms “tooth erosion” and “bulimia nervosa” combined with “OR”. After applying inclusion and exclusion criteria, 21 articles were selected, and 6 additional studies were included through manual search. A concerning link between BN and dental erosion was observed, as patients with purging-type BN frequently exhibit dental damage due to the acidic pH of vomit, which leads to mineral loss from the enamel. Early diagnosis and proper management, involving clinical identification and implementation of preventive and therapeutic strategies, are crucial to preventing severe cases. Prevention should focus on reducing acid exposure and maintaining good oral hygiene, while treatment may include fluoride application, restorations, and, in advanced cases, more invasive procedures. Interprofessional collaboration and the de-stigmatization of eating disorders are essential for improving detection and treatment, providing care that addresses both the psychological and physical issues associated with dental erosion.

Dietary Chlorella vulgaris supplementation modulates health, microbiota and the response to oxidative stress of Atlantic salmon

Microalgae are emerging as functional feed ingredients in aquaculture due to their immune-stimulating and stress-modulating properties. We investigated the potential of the microalgae Chlorella vulgaris as a feed supplement to improve the health and modulate microbiota and stress responses of Atlantic salmon. Triplicate groups of Atlantic salmon (~ 126 g) were reared in a recirculating aquaculture system (RAS) at 15 °C and received diets supplemented with 2% (CV2) or 14% (CV14) spray-dried C. vulgaris daily, 14% once weekly (CV14w), or a control diet (CD) for 8 weeks. Subsequently, all groups were exposed to an acute one-hour peracetic acid (CH3CO3H; PAA) treatment, a commonly used disinfectant in RAS. While CV14 increased feed conversion (FCR) significantly, feeding the diets CV2 and CV14w improved protein retention efficiency. CV14 significantly modulated beta-diversity in the intestinal digesta and mucosa, but this effect was already visible in fish fed CV2. Feeding CV14 and, to a lesser degree, CV2 increased the relative abundances of Paenarthrobacter and Trichococcus in the digesta and mucosa, which are able to metabolize complex carbohydrates. However, the same diets reduced the abundance of the lactic acid bacteria Lactobacillus and Weissella in the digesta and Floricoccus in the mucosa. Peracetic acid exposure induced systemic stress (increase in plasma glucose and cortisol) and a local immune response in the gill, with the most prominent upregulation of several immune- and stress-regulated genes (clra, cebpb, marco, tnfrsf14, ikba, c1ql2, drtp1) 18 h after exposure in fish fed the control diet. Fish receiving CV14 once a week showed a reduced transcriptional response to PAA exposure. Catalase protein abundance in the liver increased following exposure to PAA, while superoxide dismutase abundance in the gill and liver was increased in response to C. vulgaris inclusion before stress. Overall, the results highlight that a high (14%) inclusion rate of C. vulgaris in feed for Atlantic salmon impairs feed conversion and shifts the intestinal microbiota composition in digesta and mucosa. Weekly feeding of C. vulgaris proves a viable approach in improving protein retention and improving transcriptional resilience towards oxidative stress in increasingly intensive production systems. Thereby this study may motivate future studies on optimizing temporal feeding schedules for health-promoting aquafeeds.

Characterization of Mechanical Properties and Surface Wettability of Epoxy Resin/Benzoxazine Composites in a Simulated Acid Rain Environment

Despite the robustness of thermosetting coatings in various applications, prolonged exposure to acidic environments can cause gradual deterioration, leading to structural or functional damage. This study investigates composite materials comprised of cycloaliphatic epoxy resin (CER) and benzoxazine (BZ) at three different weight ratios: 50:50, 25:75, and 0:100. These composites were exposed to nitric acid, simulating acid rain, for durations ranging from 1 to 5 h. The specimens were characterized for weight change, mechanical properties (flexural strength and short beam strength), and surface properties (contact angle and contact angle hysteresis). Although minimal changes in the physical and mechanical properties of both homopolymer and copolymer composites were detected after short acid exposure (up to 5 h), surface wettability analysis via static contact angle and contact angle hysteresis revealed more pronounced deterioration. The static contact angle decreased by 24.96% and 28.32% for homopolymer BZ and copolymer BZ-CER composites, respectively. Contact angle hysteresis increased by 19.39% and 27.80% for 5 h acid-exposed homopolymer BZ and copolymer CER, respectively. This study underscores the utility of surface wettability analysis as a valuable tool for monitoring deterioration from acidic aging in polymers, particularly in BZ-CER systems used in structural and high-performance applications.

Towards sustainable construction: Harnessing potential of pumice powder for eco-friendly concrete, augmented by hybrid fiber integration to elevate concrete performance

This study investigates the innovative use of industrial waste pozzolana, specifically pumice powder (PP), as a partial replacement for cement, combined with hybrid fibers in concrete. Seven formulations varying PP content from 10 % to 35 % were tested, identifying 15 % PP as optimal. PP improved porosity due to its fineness, leading to better homogeneity, a refined microstructure, and an optimum compressive strength of 28.8 MPa with reduced permeability, enhancing durability. Hybrid fibers, including steel fibers (SF) from waste tires and polypropylene fibers (PF), improved toughness, ductility, and resistance to brittle failure. Tests on hybrid fiber-reinforced concrete (HyFRC) mixes with 1 % and 2 % hybrid fibers showed up to an 18.09 % increase in compressive, tensile, and flexural strengths. Energy dissipation in compressive response improved by 544.20 %, while flexural and splitting responses increased by up to 299.65 % and 208.57 %. Durability assessments in hydrochloric (HCl) and sulfuric acid (H2SO4) exposure revealed the synergy of fibers and PP enhanced resistance to chemical degradation, with high PF mixes losing as little as 0.04 % strength. Scanning electron microscopy (SEM) confirmed a dense, well-bonded matrix with reduced porosity. Analytical characterizations of mixtures such as energy dispersive x-ray spectroscopy (EDX) were studied. Regression models developed using Popovic’s and Mander’s models, accurately predicted HyFRC stress-strain behavior, closely aligning with experimental results. The integration of PP and hybrid fibers not only improved mechanical properties but also extended service life in harsh environments, offering a cost-effective, sustainable concrete solution.

Distal contractile integral and other key predictors of mean nocturnal baseline impedance: The role of esophageal peristaltic vigor in mucosal permeability.

Understanding the relationship between distal contractile integral (DCI) and mean nocturnal baseline impedance (MNBI) could shed light on new diagnostic and treatment strategies, specifically concerning nocturnal reflux. This study aimed to assess this relationship to enhance our comprehension of the interplay between esophageal contractility and mucosal permeability. We identified adult patients who had high resolution esophageal manometry and pH-impedance tests performed within a 30-day period between December 2018 and March 2022. A random forest model was used to identify significant predictors of MNBI, assisting with variable selection for a following regression analysis. Subsequently, both univariable and multivariable regression models were utilized to measure the association between predictors and MNBI. Our study included 188 patients, primarily referred for testing due to reflux. The most common motility diagnoses were normal (62%) followed by possible esophagogastric junction outflow obstruction (22%). The mean DCI was 2020 mmHg∙s∙cm and MNBI was 3.05 kΩ. The random forest model identified 12 significant predictors for MNBI, key variables being acid exposure time (AET), total proximal reflux events, intraabdominal lower esophageal sphincter length, hiatal hernia presence, and DCI. Subsequent multivariable regression analyses demonstrated log AET (β = -0.69, p = <0.001), total proximal reflux events (β = -0.16, p = 0.008), hiatal hernia presence (β = -0.82, p = 0.014), log DCI (β = 1.26, p < 0.001), and age (β = -0.13, p = 0.036) as being significantly associated with MNBI. DCI is a key manometric predictor of MNBI emphasizing the role of manometry in detecting reflux risk and the need for its consideration in reflux management.

Sociodemographic and dietary determinants of glyphosate exposure in a NYC-based pregnancy cohort

Previous studies have provided evidence for associations between glyphosate and aminomethylphosphonic acid (AMPA) exposure and adverse birth outcomes. However, few pregnancy cohort studies have investigated dietary and other determinants of glyphosate and AMPA exposure. We aimed to identify dietary and sociodemographic factors that predict glyphosate and AMPA exposure in a contemporary, urban pregnancy cohort in the US. The study included 725 pregnant participants from the New York University Children's Health and Environment Study (NYU CHES) in New York City. Urinary concentrations of glyphosate and AMPA, determined by high-performance liquid chromatography and tandem mass spectrometry, were analyzed in urine collected from NYU CHES participants across three prenatal time points. The Diet Health Questionnaire II was completed to capture dietary intake during the prenatal period. Descriptive statistics and bivariate linear models were used to assess determinants of urinary glyphosate and AMPA concentrations. Median urinary glyphosate and AMPA levels were 0.36 ng/mL and 0.37 ng/mL, respectively. Lower glyphosate levels were associated with younger age, obesity, public insurance, being single, and lower educational attainment. Nuts, seeds and whole grain intake was associated with increased urinary glyphosate concentrations. Urinary glyphosate concentrations were lower in summer than in winter. The study findings highlight widespread exposure to glyphosate and AMPA in this pregnancy cohort, with nuts/seeds and whole grains identified as possible dietary sources of exposure. High detection rates in the study population necessitate further research on dietary exposure patterns and perinatal outcomes to inform targeted interventions and reduce exposure in vulnerable populations.

Development and assessment of eco- and user-friendly geopolymeric stabilizers for sustainable soil improvement

This paper presents an innovative approach to address inherent limitations in traditional geopolymerization methods by focusing on producing eco and user-friendly mechano-chemically activated geopolymeric (M-GP) stabilizers for soil stabilization applications. A comparative analysis is conducted to benchmark the effectiveness of these stabilizers against conventionally activated geopolymer (C-GP) stabilizers. The study also investigates the influence of ground granulated blast furnace slag (GGBFS) amount on the mechanical and durability characteristics of stabilized soil specimens. Furthermore, the effect of activation techniques on the efficacy and strength of soil after sulfuric acid (H2SO4) exposure was investigated. The durability performance was evaluated by submerging the samples in a 1 % H2SO4 solution for a period of 60 and 120 days. The evaluation addresses various aspects such as visual appearance, mass changes, unconfined compressive strength (UCS), ultrasonic pulse velocity (UPV) and the Fourier transform infrared spectroscopy (FTIR) of geopolymer-stabilized soil samples. Results indicate that the UCS of M-GP samples surpassed C-GP-stabilized soil by 12–45 %. Moreover, the geopolymer-stabilized soil exhibited a significant increase in strength, with improvements of 114 %, 247 %, and 361 % observed at GGBFS content levels of 50 %, 75 %, and 100 % by weight, respectively. After exposure to the H2SO4 solution, M-GP-stabilized soil demonstrated superior resistance to sulfuric acid compared to C-GP-stabilized soil. The residual ultimate compressive strength (UCS) for M-GP and C-GP specimens was 80 % and 76 % respectively after being subjected to the H2SO4 solution for 60 days. However, these values further declined to 53 % and 48 % after 120 days of exposure. In addition, the result showed that geopolymer-stabilized soil containing 75 % slag exhibited superior resistance to H2SO4 compared to other stabilized soil samples.

PROTEIN FOLDING: FUNNEL MODEL REVISED

The spatial structure of proteins, largely determined by their amino acid sequences, is also dependent on the environmental conditions under which the folding process takes place. In aqueous environments, exposure of polar amino acids is the driving factor, whereas protein stabilization in amphipathic membranes requires exposure to hydrophobic residues. This observation can be extended to all other environmental conditions under which proteins exhibit biological activity and, most importantly, to the folding process. The fuzzy oil drop (FOD) model assumes a centric location of hydrophobic residues (hydrophobic core) with exposure of polar residues towards the aqueous environment, as the influence of the aqueous environment is extended to include the contribution of other non-aqueous factors, enabling the assessment of their influence on protein structuring. The application of the modified FOD model (FOD-M) we have developed allows the environment to be represented as an external force field in the form of a continuum. The role of environmental conditions allows modification of the funnel model expressing the localization of the energy minimum as dependent on external conditions expressed by the K scale, where K measures the degree of other than polar water factors participating in folding process.

The Effect of Erosive Media on the Mechanical Properties of CAD/CAM Composite Materials.

This study aimed to investigate the effect of acidic media storage (gastric acid and Coca-Cola) on the mechanical properties of CAD/CAM materials. Three types of materials were tested: a polymer-infiltrated ceramic network (PICN) (Vita Enamic (En), VITA Zahnfabrik, Germany), a resin composite block (RCB) (Cerasmart (Cs), GC Corp, Japan), and a conventional resin-based composite (Gradia direct (Gr), GC Corp, Japan), which was used as a control. Beam-shaped specimens of each material, with dimensions of 16 mm × 4 mm × 1.5 mm, were prepared (90 in total). The specimens were divided into subgroups (10 each) and stored for 96 h in either gastric acid, Coca-Cola, or distilled water. Flexural strength and elastic modulus were evaluated using a three-point flexural strength test with acoustic emission (AE) monitoring. Vickers microhardness was measured before and after storage in gastric acid and Coca-Cola. Data were statistically analysed using two-way and one-way ANOVA, the Tukey's post hoc, and independent t-test at a significance level of 0.05. The results showed that Cs and En maintained their flexural strength and elastic modulus after acidic media exposure, while Gr experienced a significant decrease in flexural strength following gastric acid storage (p < 0.01). Initial crack detection was not possible using the AE system, impacting the determination of flexural strength. Exposure to acidic media decreased all materials' microhardness, with Gr showing the most notable reduction (p < 0.0001). Gastric acid had a greater impact on the microhardness of all tested materials compared to Coca-Cola (p < 0.0001). In conclusion, storage in erosive media did not notably affect the flexural strength or elastic modulus of CAD/CAM composites but it did affect hardness. CAD/CAM composite blocks demonstrated superior mechanical properties compared to the conventional composite.

Peracetic Acid Emissions and Exposures during Building Disinfection Events

Since the onset of the COVID-19 pandemic, there has been a significant increase in chemical disinfection of high-touch surfaces in buildings. Peracetic acid (PAA) is a commercially available and widely used disinfectant for inactivation of viruses and bacteria. The objective of this study is to evaluate indoor PAA emissions and exposures during full-scale building disinfection events via real-time PAA measurement in a test house. The measurements revealed that PAA-based surface disinfection can lead to a significant increase in PAA concentrations in indoor air (0.1–1 mg/m3). PAA emission factors (EFs) for spray-based products ranged from 0.22–0.59 mg of PAA emitted per mg of PAA sprayed, indicating that a significant fraction of the PAA applied to surfaces is emitted into the indoor atmosphere. Inhalation intake fractions (iFs) ranged from 1,597–3,436 ppm for a one-hour exposure period, demonstrating that around 0.16–0.34% of the PAA emitted into indoor air can be inhaled by an occupant during a disinfection event. iFs were similar between the active disinfection period and the subsequent concentration decay period, suggesting that inhalation intake is important both during and after the disinfectant is applied. Real-time breathing zone (BZ) experiments demonstrated that occupants can be exposed to elevated PAA concentrations beyond those measured in the bulk indoor air due to the source-to-BZ proximity effect inherent in disinfection processes. The PAA EFs enabled modeling of PAA dynamics in different indoor environments. Model results show that PAA concentrations often exceed exposure limits, indicating a need for improved exposure mitigation strategies.

Layered double hydroxide nanozyme (LDHzyme)-assisted high-performance electrochemical analysis of organ transplant therapeutic drug concentration

The variability in mycophenolic acid (MPA) exposure levels among organ transplant patients is substantial and directly influences the drug’s therapeutic efficacy. Therefore, precise monitoring of MPA blood concentrations is imperative to devise personalized diagnostic and treatment plans tailored to individual patient profiles. In this study, we developed a screen-printed carbon electrode (SPCE) incorporating Layered Double Hydroxide-based nanozymes (LDHzymes) and multi-walled carbon nanotubes (MWCNT) to achieve high-sensitivity and stable determination of MPA in blood samples. We synthesized three distinct LDHzymes via a straightforward co-precipitation method, selecting CuMn-LDHzyme for its superior electrochemical properties and laccase activity in the context of MPA detection. The sensor’s performance was enhanced by the amalgamation of CuMn-LDHzyme with MWCNT, leveraging the laccase-like activity of CuMn-LDHzyme and the exceptional conductivity of MWCNT to amplify the oxidation current response to MPA. This integration significantly bolstered the sensor’s detection capabilities. The developed electrochemical sensor exhibited remarkable characteristics, including high selectivity, stability, repeatability, and reproducibility. It demonstrated a notable sensitivity with a detection range of 0.5 µM to 200 µM for MPA, and a detection limit of 0.1 µM, effectively detecting MPA in mouse blood samples. These attributes underscore the sensors as promising tool for clinical drug detection, ensuring fast and precise monitoring of MPA levels in organ transplant patients. This innovative approach holds significant promise for advancing personalized medical care and improving therapeutic outcomes.

External Validation of a Limited Sampling Strategy for the Estimation of Mycophenolic Acid Exposure Between Different Assay Methods: PETINIA and HPLC Methods.

A limited sampling strategy (LSS) for estimating the area under the plasma concentration-time curve (AUC0-12) of the immunosuppressant mycophenolic acid (MPA) is used for therapeutic drug monitoring (TDM) in clinical practice. Our study delves into the applicability of the MPA AUC0-12 LSS, originally developed using particle-enhanced turbidimetric inhibition immunoassay (PETINIA) measurements, to those obtained via high-performance liquid chromatography with ultraviolet detection (HPLC-UV). We developed an LSS for estimating MPA AUC0-12 based on PETINIA measurements in 32 adult kidney transplant patients who were receiving mycophenolate mofetil. Validation of this strategy was conducted in an additional 14 adult kidney transplant patients (validation sets) through measurements obtained by both PETINIA and HPLC-UV. Predictive performance was assessed using mean absolute error (MAE), root mean squared error (RMSE), and "good guess" defined as predicted AUC within observed AUC±15%. The three time point equation (0, 2, and 6h) emerged as optimal for estimating MPA AUC0-12, balancing predictive performance and usefulness in clinical settings. In validation sets, the coefficient of determination for observed versus predicted AUC0-12 was consistent between PETINIA (0.978) and HPLC-UV (0.958) measurements. Comparable MAE, RMSE, and "good guess" outcomes were observed for PETINIA (6.4%, 8.1%, and 85.7%, respectively) and HPLC-UV (7.6%, 9.4%, and 85.7%, respectively) measurements. Our findings support the application of the MPA AUC0-12 LSS, originally developed using PETINIA measurements, to those obtained via HPLC-UV.

Peroral Endoscopic Myotomy: Short Versus Long Esophageal Myotomy for Achalasia Cardia: A Randomized Controlled Noninferiority Trial.

The appropriate length of esophageal myotomy in peroral endoscopic myotomy (POEM) for achalasia cardia remains unclear. This study aimed to compare the outcome of short (≤3cm) and long (≥6cm) esophageal myotomy in patients with type I and II achalasia cardia. This single-blinded, randomized controlled noninferiority trial was conducted at a tertiary center between July 2021 and December 2021. Patients with achalasia types I and II were randomized into short (≤3cm) and long (≥6cm) esophageal myotomy groups. The primary outcome of the study was clinical success (Eckardt score ≤3) 1 year after the procedure. The secondary outcomes included a comparison of technical success, operating duration, occurrence of intraoperative adverse events, alterations in integrated relaxation pressure (IRP), change in barium column height after 5 minutes (1mo), and gastroesophageal reflux disease (3mo) between the groups. Fifty-four patients were randomized into the short (n=27) or long (n=27) esophageal myotomy groups. Technical success rates were 100% (27/27) and 96.3% (26/27) in short myotomy (SM) and long myotomy (LM) groups, respectively. The clinical success rates were 96.3% (26/27) and 96.2% (25/26) in the SM and LM groups, respectively ( P =0.998). The mean (±SD) length of the esophageal myotomy was 2.75±0.36cm in the SM and 6.69±1.35cm in the LM groups ( P <0.001). The mean (±SD) procedure time for the SM and LM groups was 61.22±8.44 and 82.42±14.70 minutes ( P <0.001), respectively. The mean integrated relaxation pressure (IRP), Eckardt score, adverse events, reflux esophagitis, symptomatic gastroesophageal reflux disease, and esophageal acid exposure (>6%) did not differ significantly between the 2 groups following POEM treatment. Short myotomy is noninferior to long myotomy in terms of clinical success, gastroesophageal reflux disease, and intraoperative adverse events at the short-term follow-up ( P >0.05). Short myotomy resulted in a reduced operative time ( P <0.05).