Exposure Time Research Articles

Novel insight into TRPV1-induced mitochondrial dysfunction in neuropathic pain.

Neuropathic pain remains one of the leading causes of global disability. The mechanism of neuropathic pain development and maintenance involves mitochondrial dysfunction induced-neuronal apoptosis of peripheral and central nociceptive pathways. The TRPV1 is a non-selective cation channel, which has a high Ca2+ permeability, playing an essential role in neuronal apoptosis in the spinal cord following peripheral nerve injury. However, the mechanism of how TRPV1 activation in the spinal cord induces mitochondrial dysfunction-mediate neuronal apoptosis, resulting in allodynia is unknown. Here, we found that activating the TRPV1 channel in the spinal cord using capsaicin, a TRPV1 agonist, results in mechanical and thermal hypersensitivity that were found to be mediated by neuroinflammation, elevated level of apoptosis, and a reduction in transcription of the mitochondrial complexes in the spinal cord and DRG. Moreover, during the early activation of the TRPV1 (1h, 24h, 48h following the capsaicin injection in the spinal cord) we observed a robust reduction in mitochondrial oxygen consumption in the non-phosphorylated state, ATP-linked respiration, maximal respiration, and electron transfer capacity (ETC). A more advanced experiment, wherein we controlled capsaicin, Ca2+ concentration and the exposure time in isolated spinal cord tissue (Lumbar, L1-L6), unveiled that TRPV1 activation impairing the mitochondrial function in terms of oxygen consumption, collapsing the Ψm and induction of the mitochondrial permeability transition pore (mPTP), which were reversed by the mPTP inhibitor-Cyclosporin A (CsA) during challenging the mitochondria with Ca2+ in a dose-dependent manner. More critically, injection of TRPV1 antagonist AMG9810 in the spinal cord following sciatic nerve crush reversed mechanical allodynia and modulated thermal hypersensitivity. In addition, the presence of TRPV1 antagonist-AMG9810 along with capsaicin and Ca2+ during challenging the spinal cord tissue completely prevents the early mPTP induction, the reduction in oxygen consumption and. In conclusion, our findings suggest that TRPV1 activation induces neuronal apoptosis, neuroinflammation, and mitochondrial dysfunction in the spinal cord, reflected in mechanical and thermal allodynia. Notable, the mitochondrial dysfunction following the TRPV1 activation in the spinal cord includes crucial elements that contribute to neuronal death, including mPTP induction, reduction in Ψm and oxygen consumption. Strikingly, regulating the TRPV1 following sciatic nerve injury reverses hypersensitivity probably via protection of the mitochondrial, suggesting a fundamental role for the TRPV1 pathway in mitochondrial dysfunction-mediated pain development.

Discovery of Noninvasive Biomarkers for Radiation Exposure via LC-MS-Based Hair Metabolomics.

Ionizing radiation exposure from a potential nuclear energy plant leak or detonation of a nuclear weapon can cause massive casualties to both warfighters and civilians. RNA, proteins, and metabolite biomarkers in biological specimens like blood and tissue have shown potential to determine radiation dose levels. However, these biomarkers in blood and urine are short-lived, typically detectable within hours or a few days. To address the need for stable, long-term radiation exposure biomarkers, we developed two mass spectrometry-based methods using noninvasive hair samples to identify radiation-exposure biomarkers. Our results show that hippuric acid and 5-methoxy-3-indoleacetate significantly increase after higher (4 gray) doses of gamma irradiation compared to lower (1 and 2 Gy) doses or nonexposed hair samples. While 2-aminooctadec-4-ene-1,3-diol, oleoyl ethanolamide, palmitoylcarnitine, 25-hydroxy vitamin D3, vernolic acid, and azelaic acid significantly increased over time after exposure. Trimethylamine N-oxide (TMAO) was found in higher concentrations in female specimens across all time points. Further validation using a machine learning model suggested that these biomarkers can predict differences in the exposure dose and time point. Our findings highlight the potential of noninvasive hair sample analysis for assessing radiation exposure, offering a viable alternative to address critical public health concerns of unexpected radiation exposure.

Outcomes of K-Clip Implantation for Functional Tricuspid Regurgitation Accompanied with Persistent Atrial Fibrillation

Background: Atrial fibrillation (AF) has been identified as a risk factor for functional tricuspid regurgitation (FTR) in the absence of other known etiologies, although limited interventional options are available. K-Clip™, a novel transcatheter tricuspid annuloplasty device, is a clip-based annular plication approach for FTR. To date, no studies have investigated the short-term outcomes of K-Clip™ for patients with severe FTR associated with AF. Therefore, the aim of this study was to explore the feasibility and effectiveness of transcatheter annular repair with K-Clip™ for FTR in patients with persistent AF. Methods: Patients with FTR and persistent AF who underwent transcatheter annular repair with K-Clip™ at nine centers in China during the inclusion period were included (This study derived from Confirmatory Clinical Study of Treating Tricuspid Regurgitation With K-Clip™ Transcatheter Annuloplasty System [TriStar study}). Baseline data, imaging results, and follow-up data were collected. Results: All 52 patients (23 men, 74.02 ± 7.03 years) received successful intervention, and the mean operation time and radian exposure were 2.64 ± 1.09 h and 133.33 ± 743.06 mGy, respectively. No death cases and a low major adverse event occurrence rate were reported in 30 days. A significant decrease in FTR was documented, and TR remained severe in only two patients (3.8%). The regurgitation volume decreased significantly, accompanied by a notable reduction in the effective regurgitation orifice area and tricuspid annulus diameter, which subsequently led to the reversal of right heart remodeling. Furthermore, a decrease in pulmonary artery systolic pressure and an increase in cardiac output were documented. Conclusions: Transcatheter annular repair with K-Clip™ showed favorable short-term prognosis and significant improvement in FTR in patients with severe FTR associated with persistent AF. K-Clip™ could be a novel option for that group of patients.

Chemical Energy Lights Up Europium‐Based Ultra‐bright Afterglow for Bioanalysis Application

Photochemical afterglow materials are gaining great attention for the property to continuously emit light after the excitation source is removed. However, their limited luminescence quantum yield (QY) and brightness hinder the use in biological applications. In this study, we introduce a novel photochemical afterglow system that combines a newly designed photoenergy cache unit (PCU) with an emitter through coordination covalent bonds. The PCU boasts a dark state to significantly emit photons only through chemiexcitation in the process of photochemical reactions, facilitating direct energy transfer to the emitter and resulting in bright afterglow. The related mechanisms further guided us to achieve the highest reported afterglow luminescence quantum yield of 27.5%. The system can be encapsulated and dispersed in aqueous solutions for in vivo bioimaging in living mice under mild and simple conditions (low concentration, low excitation power, short excitation time, short exposure time), and also for in vitro diagnostic through lateral flow immunoassay, enabling the highly sensitive detection of the inflammatory biomarker serum amyloid A (SAA) and demonstrating excellent correlation with clinical test results. This study offers new insights into enhancing luminescence QY and brightness of afterglow, highlighting the potential of such systems for further biomedical applications.

Chemical Energy Lights Up Europium-Based Ultra-bright Afterglow for Bioanalysis Application.

Photochemical afterglow materials are gaining great attention for the property to continuously emit light after the excitation source is removed. However, their limited luminescence quantum yield(QY)and brightness hinder the use in biologicalapplications. In this study, we introduce a novel photochemical afterglow system that combines a newly designedphotoenergy cache unit (PCU) with an emitter throughcoordination covalent bonds. The PCU boastsa dark state to significantly emit photons onlythrough chemiexcitationin the process of photochemicalreactions, facilitating direct energy transfer to the emitter and resulting in bright afterglow. The related mechanisms further guided us to achieve thehighest reported afterglow luminescencequantum yieldof 27.5%. The systemcan be encapsulated and dispersed in aqueous solutions for in vivobioimaging inlivingmiceundermild and simple conditions(low concentration, low excitation power, short excitation time, short exposure time), and also forin vitrodiagnostic throughlateral flow immunoassay, enablingthe highly sensitive detection of the inflammatory biomarker serum amyloid A(SAA)anddemonstrating excellent correlation with clinical test results.This study offers new insights into enhancing luminescence QY and brightnessof afterglow, highlighting the potential of suchsystems for further biomedical applications.

Multiepoch Observations of the Nearby Spiral Galaxy NGC 3938 with the Chandra X-Ray Observatory

Abstract We present an analysis of two epochs of ACIS observations of the SA(s)c spiral galaxy NGC 3938 with the Chandra X-ray Observatory. The total exposure time of the observations was 95 ks, with a limiting unabsorbed luminosity of ≈1038 erg s−1 assuming a distance of 22 Mpc. A total of 47 discrete merged sources from both epochs were detected at the ≈3σ level or greater with the D25 radius. We demonstrate that at the time of the Chandra observations the nucleus was not detected. We connect the detected sources to counterparts in other wavebands to the degree possible. Based on the two epochs, we identify three variable sources and an additional two that may have varied between the two observations. We do not formally detect any of the five historical supernovae that have occurred in NGC 3938. The luminosity function of NGC 3938 is compared to a recent compilation of 38 galaxies, and we identify a potentially significant problem with the “known” distance to NGC 3938. Star formation rate and metallicity values are also computed; the star formation rate is highly dependent on the adopted distance. The metallicity appears to lie in the range of 8.2–9.2, consistent with values from other work. We include in an appendix a short discussion of the sources that lie in Chandra’s field of view but lie outside of NGC 3938.

N-acetylcysteine antimicrobial action against endodontic pathogens-systematic review and meta-analysis.

Effective root canal disinfection is crucial for the success of endodontic treatment. N-acetylcysteine (NAC), known for its antimicrobial properties, has recently been investigated as a potential endodontic irrigant or intracanal medication. This systematic review aims to assess the antimicrobial efficacy of NAC in comparison to sodium hypochlorite, chlorhexidine, and calcium hydroxide against endodontic pathogens. A comprehensive search was conducted in PubMed, Scopus, Web of Science, Cochrane Library, and LILACS databases up to April 2024, without language or date restrictions. The PICO strategy for this review were as follows: population-teeth requiring endodontic treatment; intervention-NAC used as an endodontic irrigant or intracanal medication; comparison-sodium hypochlorite, chlorhexidine, and calcium hydroxide; Outcomes: reduction in microbial load, encompassing clinical and in vitro studies. Risks of bias assessment and data extraction were conducted with two reviewers independently selecting studies, extracting data, and assessing risk of bias. A general meta-analysis was performed across all included studies, with additional meta-analyses evaluating different exposure times, NAC concentrations, control groups and evaluation methods. After removing duplicates, 9170 studies were initially identified, and seven in vitro studies were included in the systematic review, of which five were included in the meta-analysis. Data were compared using standardized mean differences within a random-effects model. No clinical studies using NAC as an antimicrobial agent were identified. The overall meta-analysis demonstrated that NAC effectively reduced Enterococcus faecalis. Further meta-analyses revealed that exposure time, NAC concentration and choice of control group significantly influenced NAC's effectiveness. NAC effectively reduced Enterococcus faecalis, showing comparable antimicrobial activity to CHX and NaOCl, especially at concentrations of 25-50 mg/mL over a 7-day exposure. Despite significant heterogeneity across studies, NAC demonstrated satisfactory antimicrobial effects in vitro. This suggests that NAC merits reconsideration as an effective intracanal medication for clinical use.

Systematic Review of Surgical Success, Complications, Revision Rates, Radiation Dosage, and Operative Time of 3D-Navigated versus Non-Navigated Spinal Procedures.

Three-dimensional (3D) navigation offers real-time guidance in surgery. However, there is limited and inconsistent data regarding the usability, safety, and efficacy. To address gaps in knowledge about 3D navigation in spinal surgery, we conducted a comprehensive review of success rates, complications, revisions, radiation exposure, and operative time associated with Federal and Drug Administration-approved 3D surgical navigation tools. This study adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and used a protocol registered on International Prospective Registration of Systematic Reviews (CRD42023404554). Ovid MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases were searched using relevant keywords for 3D surgical navigation and spinal procedures from 1946 to March 02, 2023. Two independent reviewers assessed the studies using inclusion/exclusion criteria and risk of bias tools. Statistical analyses included one-way analysis of variance, weighted-mean difference, and unpaired t-tests with Welch's correction for associations and comparisons between groups, respectively. Of the total 11,324 studies identified and 7198 screened, 62 studies totaling 3170 adult patients were included in this comprehensive review. Complication and surgical success rates have remained constant since 2004, with overall rates of 5.5% and 94.0%, respectively. When segmented by spinal region, complication rates may be moderately positively correlated with frequency of cervical and thoracic procedures (r= 0.25, P= 0.68). The most commonly reported complication was pedicle screw malposition or breach. A subset of 20 studies, totaling 1554 patients, compared the performance of 3D navigation to two-dimensional fluoroscopy or freehand navigation. There was a significant difference of 6.53% between surgical success rates of the 3D-navigated and control groups (P= 0.03). However, there was no significant difference in radiation exposure or operative time. The 3D navigation in spinal procedures has higher surgical success rates than two-dimensional fluoroscopy and freehand navigation. Included studies exhibited varying limitations, including no patient follow-up (n= 1), less than 10 patients (n= 6), various types of spinal disorders (n= 1), and varying comorbidities among participants (n= 2). Improving 3D navigation tools remains imperative to decrease operative time and radiation exposure.

Effect of beam divergence on the irradiance from dental light curing units.

This study measured the beam divergence angle and light output from dental light curing units (LCUs). Twenty LCUs were assessed using a laboratory-grade wide beam imager to determine the relationship between the beam divergence on the irradiance as a function of distance from the light tip. The irradiance (mW/cm2) and beam divergence angles (°) at 5, and 10 mm from the tips of 18 Light-Emitting Diode (LEDs), 1 Quartz-Tungsten-Halogen (QTH), and 1 Laser diode LCU. There were significant differences in the power, irradiance, and emission spectra from the 20 LCUs. At 10 mm from the LCU tip, the irradiance delivered by one LCU decreased by approximately 85.7 %, whereas this decrease was as low as 5.6 % for a different LCU. There was a positive correlation between the divergence angle reported by the wide beam imager and the reduction in irradiance. The laser diode LCU had the least beam divergence and the smallest decrease in irradiance as the distance increased. In contrast, the QTH LCU with the turbo light guide had the greatest beam divergence and the greatest reduction in irradiance as the distance increased. 50 % of the LCUs tested would require exposure times longer than 20 s to deliver 10 J/cm2 at the 10 mm distance. The wide beam imager is a useful tool for measuring the beam divergence from LCUs and predicting the effect of distance on their irradiance. At 10 mm, some LCUs may require a fivefold increase in the exposure time to deliver the same energy they deliver at 0 mm from the tip of the LCU.

Effects of anthropogenic electromagnetic fields used for subsurface oil and gas exploration (controlled-source electromagnetics, CSEM) on the early development of Atlantic haddock (Melanogrammus aeglefinus).

Controlled source electromagnetics (CSEM) uses electromagnetic fields (EMF) to detect oil reservoirs. Atlantic haddock, Melanogrammus aeglefinus, is a commercially important demersal fish species that can potentially be impacted by such surveys due to potential overlap with egg distribution. In this study, haddock eggs were exposed to EMF, replicating CSEM survey conditions in a laboratory. Three different EMF intensities were used to replicate different distances between the EMF source and the organism. Exposures lasted for 15min. A worst-case scenario, i.e. 1h exposure at the highest EMF level was also carried out. None of the treatments caused malformations, mortality or affected hatching of eggs. However, EMF exposure induced tachycardia in newly hatched larvae and reduced the size of their yolk sac reserve. The effect was significant at the lowest EMF intensity (corresponding to 1000m between the EMF source and the exposed subject) and increased with exposure time and intensity.

Vaporized Hydogen Peroxide Uptake by Tubing used for Aseptic Fill-Finish Manufacturing of Biopharmaceutical Drug Products.

Aseptic filling of biopharmaceutical products requires a grade A cleanroom environment, preferably ensured by isolators in grade C surroundings. Isolators are decontaminated before the start of filling processes using vaporized hydrogen peroxide (VHP) and filling starts at pre-defined residual VHP levels (e.g., below 0.5ppm) depending on product sensitivity towards VHP oxidation. Manufacturing equipment and consumables, including filling assemblies, are exposed to VHP during or after the decontamination cycle or after line interruptions. We studied the VHP uptake by tubing in a lab-scale model isolator to evaluate the impact of tubing properties including contact material, tubing dimensions, suppliers, and VHP exposure (concentration and exposure time). Quantifying the release of H2O2 from the tubing into solution using an Amplex Red Hydrogen Peroxide Assay, showed that H2O2 concentrations decreased linearly with an increase in wall thickness and increased with higher surface to volume ratio. We further conclude that thermoplastic elastomer and thermoplastic vulcanizate tubing did not show any measurable VHP uptake for the tested conditions, whereas significant VHP uptake occurred in different platinum cured silicone tubing depending on tubing material and supplier. We further verified the results in a GMP manufacturing isolator setting. Based on our findings, we recommend to evaluate VHP uptake of filling tubing used for fill-finish manufacturing in isolators, to reduce the risk of oxidation for active pharmaceutical ingredients or excipients.

Study of Aedes albopictus Hatching Rate by Low‐Temperature Stress

ABSTRACTAedes albopictus overwinters as eggs and lays diapause eggs under conditions of low temperatures, low humidity, and short photoperiods. We compared the hatchability of diapause and nondiapause eggs in response to cold stress. Nondiapause eggs were acquired at 27°C ± 1°C, 70% ± 5% humidity, and 16:8 (L:D) photoperiod, and diapause eggs were acquired at 21°C ± 1°C, 40% ± 5% humidity, and 8:16 (L:D) photoperiod. The obtained eggs were dried under the same conditions and then exposed to low‐temperature stress for each temperature and time. After that, eggs were transferred to a thermostat to induce hatching at room temperature, and the hatching rate and the time required for hatching were measured and analyzed by two‐way ANOVA and multiple regression analyses. When exposed to low temperatures for 1–24 h at a temperature of 0°C to −10°C, the diapause eggs had a hatching rate higher than that of nondiapause eggs in all sections. The difference in hatching rate according to temperature, exposure time, and diapause status was all considered significant at −6°C or less (two‐way ANOVA). A significant regression equation was calculated to estimate the hatching rate, a dependent variable (R2 = 0.439, p < 0.000). We found a significant difference in hatching rates for low‐temperature stress between diapause eggs and nondiapause eggs of Ae. albopictus, which may explain why Ae. albopictus spreads in high‐latitude regions. The morphological differences between diapause and nondiapause and variables such as dryness and light intensity should be studied to understand the overwintering of Ae. albopictus.

Hydrogen peroxide damage to rat liver sinusoidal endothelial cells is prevented by n-acetyl-cysteine but not GSH

Background: Reactive oxygen species (ROS) are prevalent in the liver during intoxication, infection, inflammation, and aging. Changes in liver sinusoidal endothelial cells (LSEC) are associated with various liver diseases. Methods: Isolated rat LSEC were studied under oxidative stress induced by H2O2 at different concentrations (0.5–1000 µM) and exposure times (10–120 min). LSEC functions were tested in a dose-dependent and time-dependent manner. Results: (1) Cell viability, reducing potential, and scavenging function decreased as H2O2 concentration and exposure time increased; (2) intracellular ROS levels rose with higher H2O2 concentrations; (3) fenestrations exhibited a dynamic response, initially closing but partially reopening at H2O2 concentrations above 100 µM after about 1 hour; (4) scavenging function was affected after just 10 minutes of exposure, with the impact being irreversible and primarily affecting degradation rather than receptor-mediated uptake; (5) the tubulin network was disrupted in high H2O2 concentration while the actin cytoskeleton appears to remain largely intact. Finally, we found that reducing agents and thiol donors such as n-acetyl cysteine and glutathione (GSH) could protect cells from ROS-induced damage but could not reverse existing damage as pretreatment with n-acetyl cysteine, but not GSH, reduced the negative effects of ROS exposure. Conclusions: The results suggest that LSEC does not store an excess amount of GSH but rather can readily produce it in the occurrence of oxidative stress conditions. Moreover, the observed thresholds in dose-dependent and time-dependent changes, as well as the treatments with n-acetyl cysteine/GSH, confirm the existence of a ROS-depleting system in LSEC.

Light Controls in the Regulation of Carotenoid Biosynthesis in Leafy Vegetables: A Review

Leafy vegetables are excellent dietary sources of carotenoids, offering various nutritional benefits to human health. With the growing interest in health, the enhancement of functional compounds in crops through environmental control is emerging as an important topic in the field of agricultural research. Light serves as a major environmental signal regulating carotenoid levels. Light-activated photoreceptor proteins initiate intracellular signaling pathways that regulate carotenoid metabolism in response to environmental changes. Recent studies have shown that blue and ultraviolet (UV) light wavelengths are particularly effective in accumulation of foliar carotenoids, as they trigger photo-oxidative stress while activating defense mechanisms to mitigate it. Light intensity and exposure time, as quantitative aspects of light, are also involved in carotenoid biosynthesis in a similar manner. However, although previous studies provide valuable insights into light-mediated carotenoid accumulation, the interplay of light parameters (e.g., spectrum, intensity, exposure) with crop species and growth stages remains unclear due to the lack of well-organized data. In this review, we summarize recent advanced information about light-mediated carotenoid biosynthesis in leafy vegetables and highlight an integrated experimental approach to explore optimal light conditions for maximizing carotenoid accumulation in commercial production systems.

Low-Energy Electron Beam Modification of Metallic Biomaterial Surfaces: Oxygen and Silicon-Rich Amorphous Carbon as a Wear-Resistant Coating.

Metallic biomaterials, such as cobalt chrome molybdenum (CoCrMo), Ti-6Al-4V, and 316L stainless steel are commonly used in orthopedic implant devices. Damage modes such as corrosion and wear are associated with the use of these alloys. One solution to limit wear and corrosion damage is to apply a surface coating to the medical device. In this study, using the low-energy electron beam (LEEB) of scanning electron microscopy (SEM), we induced a highly scratch-resistant oxygen and silicon-rich amorphous carbon film to grow on each of the above metallic biomaterials. LEEB interaction with adventitious surface carbon, silicone, and oxygen deposited on the above three alloys resulted in the layered-deposition formation (LEEB-LD) of a surface coating. Coating chemistry, morphology, and nano-scratch wear properties on each of the three alloys were characterized using atomic force microscopy (AFM) scratch testing and SEM/Energy dispersive spectroscopy (EDS) analysis. We hypothesized that LEEB-LD coatings could be deposited on these three metallic biomaterials with improved tribological properties than the underlying metal substrate. First, we generated coatings on all three biomaterials and documented the coating morphology (thickness and heterogeneity) and chemistry as a function of alloy, exposure time, and scan rate with coating thicknesses generated between 5 and 50 nm after 60 min of treatment, with each factor affecting the thickness. EDS maps showed high amounts of carbon, oxygen, and silicon in the modified surface which depended on the alloy (e.g., CoCrMo and SS had similar compositions while Ti had higher oxygen in the coatings). Coated and uncoated surfaces were then subjected to diamond scratch testing in an AFM at increasing force until the coating delaminated from the surface. Scratch-depth versus load and nominal Hertzian stress were plotted for both the uncoated and coated surfaces. We found that scratch depths were 40%, 75%, and 38% smaller on CoCrMo, Ti, and SS coatings, respectively, at the peak contact stresses tested (⍺ < 0.05), indicating higher hardness and wear resistance for the coatings. These results support the hypothesis that controlled thickness LEEB-LD oxygen and silicon-rich amorphous carbon coatings can be systematically generated using low-power electron beams and that these coatings have increased tribological (scratch-resistance) properties compared to the substrate metal.

Study of Gelatin Copolymer Hydrogel Based Polyaniline and Correlation Between Structure and Reactivity of Substituted Polyaniline Based Gelatin Solution as Gamma Radiation Dosimeters

ABSTRACTPolyaniline and its derivatives based on polymer solution and hydrogels were prepared in situ to be used as colorimetric dosimeters using green nontoxic and cheap polymers as gamma radiation dosimeters. The prepared polymer hydrogel and solutions were characterized by their transparency and were highly applicable for gamma radiation dosimetry. Polymerization was carried out in two systems, based on gelatin solution, and (gelatin/acrylamide/polyvinyl alcohol) (G/PAm/PVA) hydrogel. Different dosimetric parameters, absorption spectra, response curves, sensitivity, G‐value, and relative stability were studied. The two systems showed remarkable colorimetric changes from blue to green and excellent color stability for a long period under different storage conditions of light and dark. The applicable dose range was from 0 up to 40 kGy and 0 up to 15 kGy for the solution and hydrogel system, respectively. Also, Hammett correlation between the structure of PANI and its p‐OCH3, p‐CH3, p‐OH, and p‐Cl derivatives using the time of radiation exposure instead of reaction rate was investigated through the (σ)‐log k/k0 plot. The linear plot with slope (ρ) equals to (+1.143) indicated that the sensitivity of (PANI) is enhanced by electron withdrawal substituents. The results obtained confirmed that protonation occurs, which decreases the density of the electrons on the nitrogen atom, facilitating its cleavage by radiation, and leading to fast degradation into lower molecular components.

Correlating Dose and Time of Prenatal Alcohol, Smoking, and Drug Exposure on Craniofacial Morphology: A Systematic Review

Correlating Dose and Time of Prenatal Alcohol, Smoking, and Drug Exposure on Craniofacial Morphology: A Systematic Review

Children with autoimmune hepatitis receiving standard-of-care therapy demonstrate long-term obesity and linear growth delay

Background: Standard-of-care therapy in children with autoimmune hepatitis (AIH) includes induction with prednisone 1–2 mg/kg daily with gradual weaning of the dose. We aimed to test the hypothesis that children with AIH receiving standard-of-care treatment have altered growth trajectories. Methods: Children diagnosed with AIH between 1997 and 2023 at SickKids had serial growth measurements. Mixed effect models assessed the impact of time and daily steroid exposure on z-scores. Kaplan-Meier survival methods were used to estimate the cumulative incidence of new-onset growth impairments. A time-dependent Cox proportional hazards model was constructed to determine predictors for growth impairments. Results: Sixty-one children (66% females, median age at diagnosis 11.5 y) were included. BMIz showed a sharp increase, and HAZ declined significantly without returning to baseline. Each 1 mg/kg/d prednisone exposure increased BMIz gain in the first 6 months by 0.27 ([95% CI: 0.11, 0.42], p = 0.001), and decreased HAZ by −0.02 ([95% CI: −0.03, −0.01], p = 0.005). Children diagnosed before puberty exhibited a higher occurrence of excessive weight gain (72.2% vs. 49.3%; log-rank p &lt; 0.01) and obesity (63% vs. 31.5%; log-rank p &lt; 0.01) compared to those diagnosed during puberty. In a Cox proportional-hazards model, young age at diagnosis and daily prednisone dose &gt;10 mg 6 months after diagnosis were predictors for linear growth delay. Conclusions: This study demonstrates that children with AIH receiving standard-of-care therapy demonstrate altered growth trajectories, long-term excess weight gain, obesity, and linear growth delay. Young age at diagnosis and &gt;10 mg of daily prednisone at 6 months are predictors for linear growth delay. These data indicate the need to re-evaluate standard treatment algorithms for pediatric AIH in terms of steroid dosing and potential nonsteroid alternatives.

Bioactive-based spray and spot-on formulations: Development, characterization and in vitro efficacy against fleas and ticks.

The flea Ctenocephalides felis felis and the tick Rhipicephalus sanguineus are ectoparasites of great importance in veterinary medicine that can affect pets, also impacting the lives of owners due to the possible transmission of zoonoses. Due to the negative impact on animals, owners and the environment, synthetic chemicals are being replaced by natural alternatives. Eugenol and carvacrol stand out as bioactive substances with potential antiparasitic activity. The aim of the present study was to develop and characterize physicochemically spray and spot-on formulations containing bioactives alone and in combination and to evaluate their ectoparasiticidal activity through in vitro bioassays of the knockdown effect and residual efficacy against adult fleas and ticks. Regarding flea knockdown, spot-on formulations achieved maximum mortality in a shorter period than spray formulations, 2h for carvacrol plus eugenol (SCE) and 4h for carvacrol (SC) and eugenol (SE) alone, compared to 15, 30 and 45min for the spot-on formulations of carvacrol (PC), both substances together (PCE) and eugenol alone (PE), respectively. For tick control, the formulations required longer exposure times than for fleas, so that 100% control took 6h for PCE, followed by 12h for SCE and PE, and 24h for PC, SC and PE. Regarding residual efficacy against fleas, the spray and spot-on formulations remained active for approximately 90 and 45 days, respectively. In general, formulations containing associated bioactives had a faster knockdown effect than formulations with only one in their composition, indicating a synergistic effect of the two bioactive substances against fleas and ticks.

Crystalline phase transition of ultra-thin Ni-silicide film during SiH4 exposure

Abstract Formation of an ultrathin Ni-silicide on SiO2 by exposing a Ni ultrathin film to pure SiH4 gas at 280 °C was tried. During the formation, impacts of Ni-film thickness and SiH4 exposure time on silicidation reaction were investigated. It was found that surface roughness depends on the Ni-film thickness, and that, in the case of the 3 nm thick Ni-film, a smooth surface was obtained even after the SiH4 exposure. Also, it was found that the silicidation reaction is limited between 3 and 5 min, and that, after the SiH4 exposure time more than 5 min, crystalline phase transition from the Si-rich Ni-silicide to the Ni-rich Ni-silicide and formation of Si-rich Ni-silicide with poor crystallinity were confirmed. Consequently, we successfully formed the ultra-thin Ni-silicide film with the smooth surface even at the low temperature.