Change In Color Research Articles

Clinical features of neonatal testicular torsion: A retrospective analysis of 24 cases

ObjectivesTo analyze the clinical characteristics, surgical management decisions, and outcomes of Neonatal testicular torsion (NTT) in order to offer guidance for future clinical practice. MethodsRetrospectively analyzed the clinical data of patients with NTT who were admitted and underwent surgery from January 2008 to October 2023. ResultsA total of 24 neonates were enrolled in this study, all of whom were unilateral cases. Age of onset was 0 d (IQR: 0–1.8), while the median duration of symptoms was 73 h (IQR: 26–199). Clinical manifestation included enlarged scrotum (75 %), changes in scrotal color (79 %), and crying upon palpation (17 %). All patients underwent urgent bilateral exploration and performed by orchiectomy and contralateral orchiopexy. ConclusionNTT primarily occurs prenatally with insidious manifestations, often leading to omission or misdiagnosis. The testicular salvage rate is extremely low. Physicians need to attach importance to neonatal testicular examination, improve the vigilance of NTT. Early bilateral exploration does not necessarily save the affected testes, but it is more important to prevent damage to the contralateral one.

High-Output Heart Failure Secondary to Post-Traumatic Arteriovenous Fistula

Introduction: Arteriovenous fistulas are abnormal connections between the arterial and venous systems that bypass normal anatomical capillary beds. Any device, implement, or projectile that passes through an artery and vein has the potential to lead to one, thereby preventing normal blood flow through the capillary bed. Late complications of untreated arteriovenous fistulas include proximal arterial dilation, venous congestion, congestive heart failure, and distal ischemia. Objective: Describe the clinical manifestations, diagnostic, therapeutic, prognostic complexities and complications present in post-traumatic arteriovenous fistula and its association with heart failure. Material and methods: Retrospective study presentation of a clinical case. Results: The case of a 55-year-old female patient is presented, with a 2-year history of ischemic heart disease and a gunshot wound 20 years ago. Who was admitted for bypass and coronary angiography + cardiac angiography in whom no etiology of his dilated ischemic heart disease was found until Doppler ultrasound and tomography angiography was performed due to recurrence of pain in the lower limbs and changes in skin color, which revealed presence of arteriovenous fistula. The same one that was resolved with distal ligation of the popliteal vein + exclusion of aneurysm. Conclusions: Risk factors for the development of this pathology are difficult to establish. Therefore, the shotgun trauma to the left leg 20 years ago, in addition to her obesity and female sex, led to the formation of an arteriovenous fistula that would gradually produce high-grade heart failure. Endovascular AVF repair is a treatment alternative for those patients considered high risk from anesthesia, those who have a hostile groin due to excessive scar tissue, or who cannot tolerate the consequences of bleeding that can occur with surgical control. of the FAV.

Leaf Discoloration in Rhododendron Species Exposed to Phytophthora Cinnamomi Corresponds with Future Mortality

Abstract Phytophthora cinnamomi, which causes the disease root rot, is an oomycete pathogen that is damaging to woody plants, including many horticulturally important groups, such as Rhododendron. Infecting the root of plants, Phytophthora cinnamomi inhibits water uptake, leading to root damage, wilting, and increased rates of plant mortality. Some observations suggest that P. cinnamomi infection corresponds to changes in leaf coloration, though whether this indicates a plant stress response or plant damage is generally unknown. We used leaf color analysis to test for differences in leaf discoloration between plants inoculated with the pathogen and control plants. We demonstrate a significant link between leaf discoloration in Rhododendron species and Phytophthora cinnamomi inoculation. This method was most useful when mortality was not exceptionally high, and analyzers must consider mortality as well as leaf damage in quantifying effects of the pathogen. Plants with leaf discoloration were 3.3 times more likely to die 2 weeks from our leaf census than plants with no leaf discoloration (P =0.005). This method is particularly inexpensive to implement, making it a valuable alternative to multi-spectral or hyperspectral imaging, especially in contexts such as horticulture and citizen science, where the high speed and low-cost nature of this technique might prove valuable. Species used in this study: root rot disease pathogen (Phytophthora cinnamomi Rands); Rhododendron atlanticum (Ashe) Rehder; Rhododendron brachycarpum D.Don ex G.Don; Rhododendron kiusianum Makino; Rhododendron maximum L.; Rhododendron minus Michx.; Rhododendron calendulaceum (Michx.) Torr.; Rhododendron kaempferi Planch.; Rhododendron keiskei Miq. Chemicals used in this study: Fosal Select Aliette/aluminum phosphite.

The impact of Streptococcus mutans biofilms on the color stability and topographical features of three lithium disilicate ceramics.

Secondary caries around ceramic restorations is the most common reason for the replacement of fixed dental prostheses (FDPs). Therefore, it is important to examine the susceptibility of different ceramic materials to biofilm formation. This study aimed to evaluate biofilm development and associated roughness and color alterations in three lithium disilicate ceramics: Emax CAD (EC), Emax Press (EP), and LiSi Press (LP). Streptococcus mutans biofilms were grown on the three ceramics (n = 10 per group) for 7 days. Surface roughness values and color alteration were assessed before and after the biofilm using a non-contact profilometer and spectrophotometer, respectively. Biofilm growth was evaluated using colony-forming units (CFUs) and scanning electron microscope (SEM) images. The data were analyzed using one-way ANOVA and Tukey tests. There was a significant (p≤0.001) growth of S. mutans colonies on EC (6.75 ± 0.56) and EP (6.72 ± 0.54) specimens compared to LP, which showed no biofilm growth. The change in average surface roughness (∆Ra, nm) was significantly lower (p < 0.001) in the EC specimens (0.029 ± 0.003) compared to the EP (0.055 ± 0.012) and LP (0.041 ± 0.010). When the changes in the Rv and Rt values were investigated, no significant difference was observed among the groups. Following the biofilm challenge, the change in color (∆E00) was significantly lower (p = 0.005) in the LP group (1.68 ± 1.45) compared to the EC group (3.89 ± 1.50) and no significant difference was observed between the EP group (2.74±1.01) and the other two ceramics (p ≥ 0.05). LP ceramics exhibited superior resistance to S. mutans biofilm formation and associated changes in surface roughness and color compared to the Emax CAD and Emax Press ceramics. These findings suggest that the LiSi Press material may be more favorable to mitigate the risk of secondary caries.

Assessing the impact of cold plasma rotational dynamics on ginger's total phenolic content, antioxidant activity, surface structure and color using response surface methodology

This study investigated the efficacy of a rotational chamber in enhancing the effectiveness of cold plasma application to augment antioxidant activity and phenolic content in ginger (Zingiber officinale). To address the limitation of cold plasma (CP), which predominantly treats only the surface layers of samples, we implemented rotational techniques during the treatment. This methodology facilitates a more uniform treatment, ensuring that all layers of the samples are effectively exposed to plasma. We employed response surface methodology (RSM) to analyze the effects of three variables: power (10–90 W), treatment time (1–30 min), and pressure (0.4–0.9 mbar), along with a categorical variable for rotation. CP treatment (65 W, 0.7 mbar, 1 min with rotation) resulted in a significant increase in antioxidant activity compared to non-treated samples, determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) ABTS assays, and total phenolic content reaching their highest values of 100.9 Trolox equivalent (TE) μmol⋅L−1, 8.23 Fe2+⋅g−1, 0.293 μmol⋅g−1, and 32.80 gallic acid equivalent (GAE)/g, respectively. There were no significant changes in color. Scanning Electron Microscopy (SEM) analysis revealed that the samples treated with CP exhibited a smoother surface, albeit with minimal damage to cell walls in our selected samples. Including a rotational feature as a unique upgrade to the cold plasma, the glow discharge device demonstrated positive enhancements and preservation of antioxidant activity and phenolic compounds.

Influence of Long-Term Freezing of Carcasses in Pre- and Post-Rigor Mortis Stages on the Technological and Nutritional Parameters of the Longissimus lumborum Muscle of Botucatu Rabbits.

The aim was to assess the impact of long-term storage on the quality of Botucatu rabbit meat frozen in pre- and post-rigor stages. The stability of the technological and nutritional parameters of Longissimus lumborum (LL) muscle was analyzed over 12 months. In the post-rigor phase, the dorsal LL surface showed a higher level (p < 0.05) of redness and saturation, while the ventral surface showed a higher level (p < 0.05) of yellowness compared to the pre-rigor LL muscle. During storage, the redness and saturation in the LL muscle decreased (p < 0.05), while the yellowness increased (p < 0.05) on both dorsal and ventral surfaces. In the first six months, the pre-rigor meat had a higher pH (p < 0.05) compared to the post-rigor meat. The fresh meat showed higher (p < 0.05) shear force values in the post-rigor stage. Over the 12-month study period, the lipid oxidation, myofibrillar fragmentation index, gross energy, and levels of protein, fat, and carbohydrates increased (p < 0.05), while the shear force, mineral content, and moisture decreased (p < 0.05). Thus, rigor mortis affects meat color in Botucatu rabbits. Fresh meat in the pre-rigor stage is softer, moister, and less acidic than post-rigor meat after 24 h of chilling. Long-term freezing enhances tenderness, regardless of the rigor phase at freezing, preserving its physical, chemical, and nutritional quality, with minor changes in color, lipid oxidation, and chemical composition.

Selection and Validation of Reliable Reference Genes for Liquidambar formosana Leaves with Different Leaf Colors.

Liquidambar formosana Hance is renowned for its rich leaf color and possesses notable advantages, such as robust adaptability, strong resistance to diseases and pests, and rapid growth, making it a preferred choice for urban greening and carbon sequestration forest initiatives. The completion of whole-genome sequencing of L. formosana has spurred an increased interest in exploring the molecular mechanisms underlying seasonal changes in leaf color, marking a significant focus in L. formosana breeding research. However, there is currently a lack of stable reference genes suitable for analyzing the expression patterns of functional genes in L. formosana exhibiting varying leaf colors. This study selected five L. formosana varieties with significant differences in leaf colors. Through the RT-qPCR analysis, and evaluation using BestKeeper, geNorm, NormFinder, Delta Ct, and RefFinder, the expression stability of 14 candidate reference genes was examined. Consequently, two reference genes (LifEF1-α and LifACT) with stable expression, suitable for RT-qPCR of L. formosana with diverse leaf colors, were identified. The stability of these selected reference genes was further validated by examining the LifbHLH137 gene, which promoted the biosynthesis of anthocyanins. This advancement facilitated molecular biology and genetic breeding investigations of L. formosana, providing essential data for the precise quantification of functional genes associated with leaf color variation.

Effect of Fe2O3 addition on synthesis of diamond single crystal under high-pressure and high-temperature conditions

The influence of Fe2O3 addition on the growth characteristics of synthetic diamonds under high-temperature and high-pressure conditions was systematically investigated in this work. Utilizing Fe2O3 as an oxygen source within the Fe-Ni-C-O system, oxygen-containing diamond single crystals were synthesized. The role of the oxygen atoms during the growth of large-sized diamonds with the {111} face as the growth surface was also analyzed. In addition, the morphology, growth rate, internal nitrogen content, and crystal quality of the crystals were examined. From our analysis, it was demonstrated that an increase in Fe2O3 addition leads to a reduction in the size of the synthetic crystals and a gradual decrease in the growth rate. The diamonds with complete crystal forms exhibited no significant change in color, and all appeared yellow. When the addition exceeded a threshold, cracks appeared around the seed crystal at about 0.3 mm, resulting in a cracked crystal phenomenon. A further increase in the Fe2O3 addition resulted in the skeleton crystal, and the crystal color turned black. Fourier Transform Infrared Spectroscopy (FTIR) measurements were also conducted, indicating that the introduction of oxygen atoms increases the nitrogen content in the crystals, which in turn aggregates in the form of C-centered nitrogen. The Raman spectroscopy results showed that as Fe2O3 addition in the crystals increases, more impurities are introduced, leading to an increase in the diamond stress and a shift in the diamond Raman peak, along with an increase in the full width at half maximum. The photoluminescence (PL) characterization results indicated that with the increase of the Fe2O3 addition, the intensity of the photoluminescence peaks of NV− centers and W8 centers was enhanced, which is related to the increase in the internal C-centered nitrogen content of the crystals. From the acquired results, it was proven that Fe2O3 addition has a significant impact on the synthesis of diamond single crystals. Our work provides valuable pieces of experimental evidence for exploring the formation mechanism of natural diamonds.

A case of early childhood caries from a Medieval site in Southern Portugal: a multidisciplinary approach.

Dental caries is the most prevalent chronic infectious disease during childhood both in historical and contemporary times, but research focused on the oral health of non-adults from the past is still scant. As such, this study proposes a multidisciplinary approach to the differential diagnosis of severe dental lesions in a medieval non-adult skeleton. The skeleton of a three-year-old child recovered in the medieval necropolis of Cacela Velha (Portugal) was studied through macroscopic, radiological, elemental and stable isotope analyses. This individual exhibited enamel destruction and dentine exposure in both the maxillary and mandibular teeth, with the latter also showing changes in coloration. Elemental analysis showed that his skull presented lower values of Si, Cl, and Ca and higher of Cu compared to the control, while the concentration of P and S were significantly lower in the teeth. Early childhood caries is the most probable diagnosis for the dental lesions observed, apparently stemming from a reticulate of factors that include potential malnutrition, and the consumption of sugars in complementary feeding - even though historical sources point to the scarcity of sugar in Portugal during most of the Middle Ages.

Addressing spoilage monitoring in packaged paneer (Indian cottage cheese): Lac dye-based intelligent indicator as an innovative solution

The study aimed to develop an intelligent real-time freshness indicator for paneer (Indian cottage cheese) by immobilizing lac dye, a natural anthraquinone dye, in situ on an agarose membrane. The indicator was characterized and evaluated for freshness monitoring of paneer. The indicator exhibited color transition from purple at pH 7 to orange-red at acidic pH (2–5). For evaluation of the indicator, it was placed inside the package headspace containing paneer and stored at ambient (25 ± 1 °C) and refrigerated (8 ± 1 °C) temperatures. Color changes in the indicator showed a correlation with quality parameters and volatile organic compounds (VOCs) emitted during storage of paneer. Initially, the indicator was purple on day 0. However, once the microbial counts in paneer exceeded acceptable limits (on day 1 at 25 ± 1 °C and day 6 at 8 ± 1 °C), indicator's color shifted to orange-red. This color transition effectively categorized paneer as: ‘fresh’, ‘moderately fresh’, and ‘spoiled’. The principal component analysis outcomes confirmed that the changes in the indicator's color were closely aligned with the variations observed in paneer quality parameters. Partial least squares models derived from indicator's color parameter data successfully predicted paneer quality. The study's findings illuminate potential of lac dye-based indicator in non-destructive real-time freshness monitoring of paneer.

Comparative analysis between a HLB tolerant bud sport obtained from the ‘Flame’ grapefruit with its parental genotype

Natural bud sports can lead to the development of plants with unique phenotypic traits such as changes in color, size, or disease resistance. In this report, biochemical, transcriptomic, and genomic analyses were conducted on a natural bud sport of the ‘Flame’ grapefruit compared to its wild-type genotype in response to Huanglongbing (HLB; Citrus greening) disease. The biochemical analysis of the bud sport genotype leaves revealed an increase in chlorophyll content and a decrease in starch accumulation compared to the wild-type genotype. Transcriptomic analysis identified significant differences between the bud sport and wild-type genotypes, with 738 genes being upregulated and 3899 genes downregulated. Differential expression of genes encoding for phloem proteins, phytohormones such as jasmonic acid and gibberellic acid, pathogenesis-related (PR) genes, and their negative regulators were observed in this study. Callose deposition-related genes were downregulated in the bud sport, suggesting that the bud sport ‘Flame’ grapefruit might modulate phloem genes in response to Candidatus Liberibacter asiaticus (CaLas) without excessive callose deposition. Overexpression of WRKY transcripts involved in pathogenesis-related (PR) gene expression, such as the NIM1 interacting 1 transcript, suggests activation of PR-mediated defense. Downregulation of carbohydrate metabolism and several major transporter transcripts may be responsible for resource allocation strategies to limit bacterial spread. Altered expression of some of the key genes and pathways in the bud sport produced a better response to CaLas than the wild-type following HLB infection, indicating that the bud sport may be modulating its defense strategies to cope against the pathogen. The SNP polymorphism identified through genotyping-by-sequencing determined meaningful genetic distinction between bud sport and wild-type genotypes derived from the same plant, facilitating precise genetic characterization and analysis.

Comparative Evaluation of the Effect of Microwave, 1% Sodium Hypochlorite, and Sodium Perborate Disinfection on the Color Stability of Two Nanoparticle-Reinforced Heat-Polymerized PMMA Denture Base Resins: An In Vitro Study.

Introduction Older adults experience significant improvement in their quality of life by using removable prosthetics to replace missing teeth. Poly(methyl methacrylate) (PMMA) has become the most popular material for denture bases due to its ease of use and affordability. Recently, scientists have started adding nanoparticles like titanium dioxide (TiO2) and zirconium oxide (ZrO2) to PMMA to enhance its physical properties. These resins with nanoparticles need to stay the same color after being disinfected in different ways if they are going to be used for a long time. So, the purpose of this investigation was to assess whether or not there exists any difference between two kinds of thermally cured acrylic resin for artificial tooth bases strengthened with nanoparticles when subjected to various chemical sterilizers alongside microwave irradiation, as well as determine their comparative colorfastness levels. Materials and methods In this lab experiment, we tested how well 5% TiO2 and 7% ZrO2 nanoparticle-reinforced PMMA resins held their color when exposed to microwave irradiation, 1% sodium hypochlorite, or sodium perborate disinfection. We made 120 specimens shaped like discs; half were treated using one method, while the other half were treated using a different method. Color was measured at baseline (T0), after one cycle (T1), after five cycles (T2), and after six months (T3) using a reflectance spectrophotometer, which calculates the color difference (∆E). Results All three methods of disinfection caused significant color changes (p<0.001); however, sodium perborate caused the least amount of change, followed by 1% sodium hypochlorite and microwave irradiation. The mean ∆E values showed that after one day, there was a change in color by 1.1 due to microwave disinfection, which increased to 5.7 after five days; on the other hand, for 1% sodium hypochlorite, the change was recorded as 0.7 after one month and 1.6 after three months and finally reached up to 2.6 after six months, while sodium perborate showed the least amount of change, with ∆E values recorded as 0.2 after one month, 0.5 after three months, and 0.8 after six months. Conclusion Sodium perborate proved to be the most effective disinfectant for maintaining color stability in 5% TiO2 and 7% ZrO2 nanoparticle-reinforced PMMA resins, thus making it ideal for routine disinfection. Therefore, according to this study, sodium perborate should be used as a disinfection method because it results in minimal color change in nanoparticle-reinforced PMMA dentures.

Chitosan-stabilized gold nanoparticles decorated with a thiodiacetic acid nanoprobe for selective detection of arsenic(iii) in rice and water samples.

A sensitive and selective method for the detection of arsenic(iii) (As3+) based on chitosan-stabilized gold nanoparticles (CS/AuNPs) decorated with a 2,2'-thiodiacetic acid (TDA) nanoprobe was developed and used to detect and indicate the contamination of rice, drinking water and environmental water samples. AuNPs were reduced and stabilized with CS and subsequently functionalized with TDA. As3+ interacted with the carboxylate group of TDA to form an As-TDA complex, inducing the aggregation of CS/AuNPs@TDA. The aggregation of CS/AuNPs@TDA was accompanied with a change in color from red to bluish purple and a shift in surface plasmon resonance wavelength from 525 nm to 645 nm. The response for the detection of As3+ was linear at concentrations from 10 to 1000 μg L-1 with a limit of detection of 6.1 μg L-1. The method exhibited selectivity toward As3+ among various cations (As5+, Cu2+, Fe3+, Fe2+, Hg2+, Al3+, Cr3+, Cd2+, Co2+, Ni2+, Pb2+ and Zn2+) and anions (Br-, Cl-, F-, SO4 2-, NO3 - and PO4 2-). The CS/AuNPs@TDA nanoprobe was applied to detect As3+ in rice, drinking water and environmental water samples. The results were consistent with those obtained via inductively coupled plasma-optical emission spectrometry (ICP-OES). Satisfactory recoveries ranging from 88.22% to 105.74% (RSDs of 0.25-2.99%) were obtained from spiked samples.

Regulation of skin pigments in winter jujube fruit treated with elevated O2

Color deterioration is one of the major symptoms of postharvest senescence in winter jujube fruit. Elevated O2 (60 %) was applied to winter jujube fruit during storage at 0 °C and 90 % relative humidity. The changes in three major skin pigments, chlorophyll, carotenoid, and anthocyanin, were quantified to explain changes in skin color. The results showed that elevated O2 maintained the contents of chlorophyll and carotenoid during the initial stages of storage, which were 25 % higher chlorophyll a, 34 % higher chlorophyll b, and 18 % higher carotenoid compared to the control on day 7. The maintenance of chlorophyll content under elevated O2 was due to the inhibition of chlorophyll catabolism. Additionally, elevated O2 treatment also maintained carotenoid content by activating its biosynthesis rather than inhibiting its degradation. During the later stages of storage, the accumulation of anthocyanin was enhanced by elevated O2, with a 1.3-fold increase in anthocyanin observed in elevated O2-treated fruit compared to the control fruit on day 21. Elevated O2 treatment effectively activated phenylpropanoid biosynthesis and flavonoid biosynthesis pathways, leading to the accumulation of anthocyanin. This study elucidated the mechanism by which elevated O2 regulated color deterioration in winter jujube fruit.

Nature-Inspired pH-Responsive Hydrogels with Rapid and High Contrast Changes in Color, Fluorescence, and Shape Simultaneously

Nature-Inspired pH-Responsive Hydrogels with Rapid and High Contrast Changes in Color, Fluorescence, and Shape Simultaneously

Transparent bamboo as a replacement for glass: Effects of lignin decolorisation methods on weatherability

Transparent bamboo proved to be a promising substitute for glass due to its high light transmittance and excellent mechanical properties. Nevertheless, it was susceptible to outdoor weathering, which negatively affected its physical and mechanical properties. In this study, two decolorisation methods, namely the delignification method and the lignin modification method, were used to produce transparent bamboos with epoxy resin, referred to as DL-TB and LM-TB, respectively. The changes in surface color, optical and mechanical properties, wettability, thermal stability, and thermal insulation properties of transparent bamboo during accelerated UV weathering were evaluated. Additionally, the deterioration mechanism of DL-TB and LM-TB was investigated. The findings revealed that DL-TB demonstrated better transparency and mechanical properties than LM-TB, although it exhibited lower thermal insulation properties. Furthermore, DL-TB demonstrated enhanced color stability and higher hydrophobicity on weathered surfaces than LM-TB. Unexpectedly, the tensile properties of both two transparent bamboos significantly improved after weathering, especially for LM-TB, which was due to the EP post-curing and the formation of more hydrogen bonds between lignin and EP. These observations revealed that lignin played a key role in the photodegradation process of transparent bamboo, but further attempts should be made in future studies to improve its color stability.

Pink urine syndrome in an anuric patient during continuous renal replacement therapy: A case report.

Pink urine syndrome is a rare, poorly understood condition, often prompted by obesity, insulin resistance, and the drug propofol. It is characterized by pink urine or urine sediment and occurs in the absence of a heme or food-based pigment. The pathophysiology of this syndrome is not yet fully understood but is linked to a uric acid metabolism disorder. Pink urine syndrome is less familiar to anesthesiologists than other propofol infusion complications. Our case report aims to highlight this rarely encountered syndrome, whose both diagnosis and therapeutic may be challenging. We have reported the first case of this syndrome evidenced by the change in color of the effluent bag during continuous veno-venous hemofiltration (CVVHF). A 61-year-old woman was admitted to the intensive care unit following a recovered cardiorespiratory arrest due to ventricular arrhythmia. She was placed in hypothermia, sedated with propofol (300 mg/h), and started on CVVHF for oligo-anuric acute kidney injury associated with severe metabolic acidosis. A few hours after initiation of CVVHF, the effluent bag turned bright pink. Given the pink color of the effluent bag and the hypothesis of propofol-induced pink urine syndrome, propofol was replaced by midazolam. After stopping propofol, the color of effluent bag lightened. Unfortunately, the patient died on the third day of hospitalization due to diffuse cerebral edema. We report here the first case of pink urine syndrome as revealed by the change in color of the contents of the CVVHF effluent bag in an anuric patient. This syndrome is rare but significant in anesthesia/intensive care settings, where propofol is a frequently used sedative. Knowledge of this syndrome appears to be important to avoid irrelevant additional investigations and to optimize the therapeutic strategy.

Assessment of thermochromic phantoms for characterizing microwave ablation devices.

Thermochromic gel phantoms provide a controlled medium for visual assessment of thermal ablation device performance. However, there are limited studies reporting on the comparative assessment of ablation profiles assessed in thermochromic gel phantoms against those in ex vivo tissue. The objective of this study was to compare microwave ablation zones in a thermochromic tissue mimicking gel phantom and ex vivo bovine liver, and to report on measurements of the temperature dependent dielectric and thermal properties of the phantom. Thermochromic polyacrylamide phantoms were fabricated following a previously reported protocol. Phantom samples were heated to temperatures in the range of 20 - 90 °C in a temperature-controlled water bath, and colorimetric analysis of images of the phantom taken after heating were used to develop a calibration between color changes and temperature to which the phantom was heated. Using a custom, 2.45 GHz water-cooled microwave ablation antenna, ablations were performed in fresh ex vivo liver and phantoms using 65 W applied for 5 min or 10 min ( n = 3 samples in each medium for each power/time combination). Broadband (500 MHz - 6 GHz) temperature-dependent dielectric and thermal properties of the phantom were measured over the temperature range 22 - 100 °C. Colorimetric analysis showed that the sharp change in gel phantom color commences at a temperature of 57 °C. Short and long axes of the ablation zone in the phantom (as assessed by the 57 °C isotherm) for 65 W, 5 min ablations were aligned with extents of the ablation zone observed in ex vivo bovine liver. However, for the 65 W, 10 min setting, ablations in the phantom were on average 23.7% smaller in short axis and 7.4 % smaller in long axis than those observed in ex vivo liver. Measurements of the temperature dependent relative permittivity, thermal conductivity, and volumetric heat capacity of the phantom largely followed similar trends to published values for ex vivo liver tissue. Thermochromic tissue mimicking phantoms provide a controlled, and reproducible medium for comparative assessment of microwave ablation devices and energy delivery settings, though ablation zone size and shapes may not accurately represent ablation sizes and shapes observed in ex vivo liver tissue under similar conditions.

Novel benzothiazole-based fluorescent probe for efficient detection of Cu2+/S2− and Zn2+ and its applicability in cell imaging

BackgroundIn recent years, environmental pollution has been increasing due to the excessive emission of toxic ions, which has caused serious harm to human health and ecological environment. There are various methods for detecting Cu2+, S2− and Zn2+, but the traditional ion detection methods have obvious disadvantages, such as poor selectivity and long detection time. Therefore, it is still crucial to develop simple, efficient and rapid detection methods. ResultsA fluorescent probe based on benzothiazole, (E)-N'-(3-(benzo[d]thiazol-2-yl)-2-hydroxy-5-methylbenzylidene)-3,4,5-tris(benzyloxy)benzohydrazide (BT), was designed and synthesized. It was characterized using ESI-MS, 1H NMR, and 13C NMR. BT can be used as a chemosensor to detect Cu2+, S2− and Zn2+ in CH3CN/H2O (7:3, v/v, pH = 7.4, HEPES buffer: 0.1 M), with detection limits of 0.301 μM, 0.017 μM, and 0.535 μM, respectively. At an excitation wavelength of 320 nm, BT exhibits an “on-off-on” response to Cu2+/S2− and enhanced fluorescence response to Zn2+, with a change in fluorescence color from orange to green. The coordination ratio of ions to the probe was determined to be 1:1 through Job's plot and hydrogen spectral titration. The recognition mechanism was discussed in conjunction with theoretical calculations. Furthermore, the probe has been successfully used in test strips and medical swabs colorimetry, as well as live cell imaging. SignificanceThe probe BT lays the foundation for the design and synthesis of multifunctional fluorescent probes. As a portable detection method, probe BT was used to detect Cu2+, S2− and Zn2+ on strips. Furthermore, the probe was applied to biological cells to detect target ions with low cytotoxicity and excellent cell permeability. This indicating that it can be used as a potential candidate for tracking Cu2+ and S2− in clinical diagnostics and biological systems.

Integrated gold nanorods-based dual-signal platform for accurate total antioxidant capacity assessment in food samples

Accurate assessment of Total Antioxidant Capacity (TAC) in food is crucial for evaluating nutritional quality and potential health benefits. This study aims to enhance the sensitivity and reliability of TAC detection through a dual-signal method, combining colorimetric and photothermal signals. Gold nanorods (AuNRs) were utilized to establish a dual-signal method duo to the colorimetric and photothermal properties. Fenton reaction can etch the AuNRs from the tips, as a result, a blue shift in the longitudinal LSPR absorption peak was obtained, leading to significant changes in color and photothermal effects, facilitating discrimination through both visual observation and thermometer measurements. In the presence of antioxidants, the Fenton reaction was suppressed or inhibited, protecting the AuNRs from etching. The colorimetric and photothermal signals were therefore positively correlated with TAC levels, enabling dual-signal detection of TAC. The linear range of AA was 4–100 μM in both colorimetry and photothermal modes, with detection limits of 1.60 μM and 1.38 μM, respectively. This dual-signal approach achieves low detection limits, enhancing precision and sensitivity. The method thus has the potential to act as a promising candidate for TAC detection in food samples, contributing to improved food quality and safety assessment.