Biogenic amine reduction by food additives in Cheonggukjang, a Korean fermented soybean paste, fermented with tyramine-producing heterogeneous bacterial species.

This study was conducted to mitigate the food safety risks related to biogenic amine (BA) by reducing the BA content in Cheonggukjang using applicable food additives. In in-vitro experiments, of the additives tested, tartaric acid (TA), potassium sorbate (PS), and sodium benzoate (SB) considerably inhibited tyramine production of strains of Bacillus spp. and Enterococcus faecium while less affecting their growth. In addition to these three additives, two additives, glycine (GL) and nicotinic acid (NA), reported to have significant inhibitory effects in previous studies, were applied to the Cheonggukjang fermentation with prolific tyramine-producing strains of B. subtilis and E. faecium. The content of tyramine in the Cheonggukjang samples treated with TA, PS, SB, GL, and NA was significantly reduced by 27.5%, 50.7%, 51.4%, 76.1%, and 100.0%, respectively, compared to the control sample. Additionally, the content of polyamines (putrescine, cadaverine, spermidine, and spermine) in the GL-treated sample was reduced by 42.6%-62.4%. The mode of action could be attributed to inhibiting the bacterial decarboxylase activity and/or growth. Consequently, excluding NA that interfered with Cheonggukjang fermentation, GL was the most outstanding additive with an inhibitory effect on tyramine formation in food, followed by SB and PS, all of which showed a more than 50% reduction. Therefore, the use of appropriate additives could be one of the promising strategies to avoid the food safety issues implicated in BAs in Cheonggukjang.

Excited-state chemistry of the nitromethane anion mediated by the dipole-bound states revealed by photofragment action spectroscopy.

We report the first experimental observation of the excited dipole-bound state (DBS) of the cryogenically cooled nitromethane anion (CH3NO2-), where the excess electron is loosely attached to the singlet or triplet neutral-core. Photofragment and photodetachment action spectra have been employed for the dynamic exploration of Feshbach resonances located even far above the electron detachment threshold, giving excitation profiles from the ground anionic state (D0) to the DBSs which match quite well with the spectral structures of the photoelectron spectra. This indicates that the electron transfer from the nonvalence orbital (of DBS) to the valence orbital (of anion) is mainly responsible for the anionic fragmentation channels, giving strong evidence for that the DBS plays a dynamic doorway-role in the anionic fragmentation reactions. Photofragment action spectra have also been obtained for the anionic clusters of (CH3NO2)2-, (CH3NO2)3-, or (CH3NO2·H2O)-, giving the relative yields of various fragments as a function of the excitation energy for each cluster. The absorption profiles of the anionic clusters exhibit substantial blue-shifts compared to the bare nitromethane anion as their ground states are much stabilized by solvation. The anionic fragmentation pattern varies among different clusters, giving essential clues for the thorough understanding of the whole anionic dynamics such as the dynamic role of the short-lived nonvalence-bound states of the clusters.

Ultrasound-Driven Injectable and Fully Biodegradable Triboelectric Nanogenerators.

Implantable medical devices (IMDs) provide practical approaches to monitor physiological parameters, diagnose diseases, and aid treatment. However, device installation, maintenance, and long-term implantation increase the risk of infection with conventional IMDs. Therefore, medical devices with biocompatibility, controllability, and miniaturization are highly demandable. An ultrasound-driven, biodegradable, and injectable triboelectric nanogenerator (I-TENG) is demonstrated to reduce the risks of implant-related injuries and infections. The injection can be given by subcutaneous injection with a needle to minimize the implantation incision. The stable output of I-TENG is driven by ultrasound (20 kHz, 1 W cm-2 ), with a voltage of 356.8 mV and current of 1.02 µA during in vivo studies and an electric field of about 0.92 V mm-1 during ex vivo experiments. The cell scratch and proliferation assays showed that the delivered electric field effectively increased cell migration and proliferation, indicating a significant potential to accelerate healing with electricity.

An Ultrasound-Driven Bioadhesive Triboelectric Nanogenerator for Instant Wound Sealing and Electrically Accelerated Healing in Emergencies.

A bioadhesive triboelectric nanogenerator (BA-TENG), as a first-aid rescue for instant and robust wound sealing and ultrasound-driven accelerated wound healing, is designed. This BA-TENG is fabricated with biocompatible materials, and integrates a flexible TENG as the top layer and bioadhesive as the bottom layer, resulting in effective electricity supply and strong sutureless sealing capability on wet tissues. When driven by ultrasound, the BA-TENG can produce a stable voltage of 1.50 V and current of 24.20 µA underwater. The ex vivo porcine colon organ models show that the BA-TENG seals defects instantly (≈5 s) with high interfacial toughness (≈150 J m-2 ), while the rat bleeding liver incision model confirms that the BA-TENG performs rapid wound closure and hemostasis, reducing the blood loss by about 82%. When applied in living rats, the BA-TENG not only seals skin injuries immediately but also produces a strong electric field (E-field) of about 0.86 kV m-1 stimulated by ultrasound to accelerate skin wound healing significantly. The in vitro studies confirm that these effects are attributed to the E-field-accelerated cell migration and proliferation. In addition, these TENG adhesives can be applied to not only wound treatment, nerve stimulation and regeneration, and charging batteries in implanted devices.

Evaluation of Bioactive Compounds and Antioxidative Activity of Fermented Green Tea Produced via One- and Two-Step Fermentation.

This study investigated the influence of one- and two-step fermentation on bioactive compound production in fermented green tea, i.e., one-step fermented green tea (OFG) and two-step fermented green tea (TFG). One-step fermentation entailed acetic acid fermentation, while two-step fermentation consisted of lactic acid fermentation followed by acetic acid fermentation. Acetobacter pasteurianus PCH 325, isolated from an over-ripened peach, was selected for acetic acid fermentation based on its growth and organic acid production characteristics. Acetic acid fermentation conditions were optimized for one- and two-step fermentation: 3% fermentation alcohol for both processes; 8% and 4% sucrose, respectively; and fermentation at 25 °C for both processes. For lactic acid fermentation of TFG, the inoculum and optimized conditions reported previously were used. Under the optimized conditions, the acetic acid content in OFG and TFG increased 21.20- and 29.51-fold, respectively. Furthermore, through two-step fermentation, γ-aminobutyric acid and lactic acid were produced up to 31.49 ± 1.17 mg/L and 243.44 ± 58.15 mg/L, respectively, which together with acetic acid could contribute to the higher DPPH scavenging activity of TFG. This study suggests that two-step fermentation may be a valuable strategy in industry for raising the amount of acetic acid and/or providing additional bioactive compounds.

Ambient Humidity-Induced Phase Separation for Fiber Morphology Engineering toward Piezoelectric Self-Powered Sensing.

Electrospun polymeric piezoelectric fibers have a considerable potential for shape-adaptive mechanical energy harvesting and self-powered sensing in biomedical, wearable, and industrial applications. However, their unsatisfactory piezoelectric performance remains an issue to be overcome. While strategies for increasing the crystallinity of electroactive ß phases have thus far been the major focus in realizing enhanced piezoelectric performance, tailoring the fiber morphology can also be a promising alternative. Herein, a design strategy that combines the nonsolvent-induced phase separation of a polymer/solvent/water ternary system and electrospinning for fabricating piezoelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE) fibers with surface porosity under ambient humidity is presented. Notably, electrospun P(VDF-TrFE) fibers with higher surface porosity outperform their smooth-surfaced counterparts with a higher ß phase content in terms of output voltage and power generation. Theoretical and numerical studies also underpin the contribution of the structural porosity to the harvesting performance, which is attributable to local stress concentration and reduced dielectric constant due to the air in the pores. This porous fiber design can broaden the application prospects of shape-adaptive energy harvesting and self-powered sensing based on piezoelectric polymer fibers with enhanced voltage and power performance, as successfully demonstrated in this work by developing a communication system based on self-powered motion sensing.

Patterns of Restricted and Repetitive Behaviors in Toddlers and Young Children with Autism Spectrum Disorder.

Objectives: Restricted and repetitive behaviors (RRBs) are a core symptom in the diagnosis of autism spectrum disorder (ASD). The complexity of behavioral patterns has called for the creation of phenotypically homogeneous subgroups among individuals with ASD. The purpose of this study was 1) to investigate the different types of RRBs and 2) to explore whether subgroups created by RRBs would show unique levels of functioning in toddlers and young children with ASD. Methods: A total of 313 children with ASD, aged 12-42 months were included in the analysis. The Autism Diagnostic Interview-Revised was used to obtain information on the different types of RRBs by grouping 15 items into six categories. The Vineland Adaptive Behaviors Scale, a parent-reported questionnaire, was used to measure adaptive functioning. A portion of the children were analyzed separately for verbal-related RRBs based on their expressive language level. Two-step cluster analysis using RRB groups as features was used to create subgroups. Analysis of covariance while covarying for age and language was performed to explore the clinical characteristics of each cluster group. Results: Sensory-related RRBs were the most prevalent, followed by circumscribed interests, interest in objects, resistance to change, and repetitive body movements. A subset of the children was analyzed separately to explore verbal-related RRBs. Four cluster groups were created based on reported RRBs, with multiple RRBs demonstrating significant delays in adaptive functioning. Conclusion: Heterogeneity of RRBs emerges at a young age. The different patterns of RRBs can be used as valuable information to determine developmental trajectories with better implications for treatment approaches.

Virus blocking textile for SARS-CoV-2 using human body triboelectric energy harvesting.

Effective mitigation technology to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is required before achieving population immunity through vaccines. Here we demonstrate a virus-blocking textile (VBT) that repulses SARS-CoV-2 by applying repulsive Coulomb force to respiratory particles, powered by human body triboelectric energy harvesting. We show that SARS-CoV-2 has negative charges, and a human body generates high output current of which peak-to-peak value reaches 259.6 µA at most, based on triboelectric effect. Thereby, the human body can sustainably power a VBT to have negative electrical potential, and the VBT highly blocks SARS-CoV-2 by repulsion. In an acrylic chamber study, we found that the VBT blocks SARS-CoV-2 by 99.95%, and SARS-CoV-2 in the VBT is 13-fold reduced. Our work provides technology that may prevent the spread of virus based on repulsive Coulomb force and triboelectric energy harvesting.

Biofilm-associated heat resistance of Bacillus cereus spores in vitro and in a food model, Cheonggukjang jjigae.

Bacillus cereus, a foodborne pathogen, is capable of forming spores and biofilms as methods to withstand environmental stresses. These bacterial structures are an issue for food safety as they aid the bacteria survive heat sterilisation processes of foods and food contact surfaces. This study was conducted to investigate the role of the biofilm structure in providing an extra layer of protection to spores against heat treatments. For this, heat resistance of B. cereus spores in intact biofilms was compared to that of planktonic spores in vitro and in a Cheonggukjang jjigae food model. Using methods developed in this study to measure the wet and dry heat resistance of spores in intact biofilms, it was found that B. cereus spores have significantly higher heat resistances when present in biofilms rather than as planktonic spores, and that dry heat is less effective than wet heat at killing spores in biofilms. In further detail, for wet heat treatments, spores in biofilms of the strain isolated from Cheonggukjang (Korean fermented whole soybean), B. cereus CH3, had generally higher wet heat resistances than the reference strain, B. cereus ATCC 10987, both in vitro and in the Cheonggukjang jjigae food model. However, the spores in biofilms of the two strains showed similar heat resistance to dry heat, with some exceptions, when biofilms were formed in vitro or in Cheonggukjang jjigae broth. Meanwhile, B. cereus ATCC 10987 spores in biofilms had higher or similar wet heat resistances in vitro compared to in Cheonggukjang jjigae broth. Wet heat resistances of B. cereus CH3 spores in biofilms were all statistically similar regardless of biofilm formation media (brain heart infusion and Cheonggukjang jjigae broths). For dry heat, spores in biofilms of both B. cereus strains were more heat resistant when biofilms were formed in the Cheonggukjang jjigae food model rather than in vitro. Altogether, heat resistances of spores in biofilms formed in vitro and in the food environment were found to be different depending on the tested B. cereus strain, but higher than planktonic spores in any case. This is the first study examining the heat resistance of B. cereus spores in intact biofilms matrices attached to the surface, both in vitro and in a food model. Therefore, this research is valuable to understand the protective effects of biofilms formed in food environments and to reduce the food safety risks associated with B. cereus.

Suicidal ideation among the elderly living in the community: Correlation with living arrangement, subjective memory complaints, and depression.

BACKGROUND: This study aimed to investigate the correlations of living arrangement, subjective memory complaints, and depression on suicidal ideation in elderly men and women. METHODS: There were 1,412 participants (women, 63.5%) from a rural community in South Korea, aged ≥60 years (mean±SD, 73.2 ± 8.0 years). We measured suicidal ideation, subjective memory complaints, and depression using the Columbia-Suicide Severity Rating Scale, Subjective Memory Complaints Questionnaire, and the short form of the Geriatric Depression Scale, respectively. We then estimated correlations of living arrangement, subjective memory complaints, and depression with recent suicidal ideation using multivariate logistic regression analysis. RESULTS: With all participants as a group, living alone, subjective memory complaints (SMC+) and high risk of depression (HRD) were found to be significant independent predictors (p = 0.021 for living alone; p = 0.006 for SMC+; p < 0.001 for HRD, respectively) of suicidal ideation (SI+). When men and women were analyzed separately, HRD remained significant both in men and women (OR = 6.01, p < 0.005 for men; OR = 7.23, p < 0.001 for women), while living alone and SMC+ were significant only in men (OR = 3.36, p = 0.013 for living alone; OR = 3.30, p = 0.016 for SMC+). LIMITATIONS: The results may not be generalizable to the urban setting as this study included only elderly persons living in the rural community. CONCLUSIONS: Living alone and subjective memory complaints were significant predictors of recent suicidal ideation only in men while depression was a significant predictor both in men and women.

Effect of Calcium and Manganese Supplementation on Heat Resistance of Spores of Bacillus Species Associated With Food Poisoning, Spoilage, and Fermentation.

Bacterial spores often survive thermal processing used in the food industry, while heat treatment leads not only to a decrease in the nutritional and organoleptic properties of foods, but also to a delay in fermentation of fermented foods. Selective reduction of undesirable spores without such impediments is an ongoing challenge for food scientists. Thus, increased knowledge of the spore-forming bacteria is required to control them. In this study, the heat resistance results (D 100 ° C) of the spores of four Bacillus species were determined and compared to previous literature, and found that B. cereus has significantly lower heat resistance than the other Bacillus species, B. coagulans, B. subtilis, and B. licheniformis. Using the spores of these strains, this study also evaluated the effects of single and combined supplementation of calcium (0.00-2.00 mM) and manganese (0.00-0.50 mM) on heat resistance (D 100 ° C). The results revealed that the spores of B. licheniformis and B. cereus displayed the smallest heat resistance when sporulated on media rich in calcium. Conversely, B. coagulans spores and B. subtilis spores exhibited the greatest heat resistance when sporulated under calcium-rich conditions. The opposite results (stronger heat resistance for B. licheniformis spores and B. cereus spores, and smaller heat resistance for B. coagulans spores and B. subtilis spores) were obtained when the spores were formed on media poor in the minerals (particularly calcium). Based on the results, the Bacillus species were divided into two groups: B. licheniformis and B. cereus; and B. coagulans and B. subtilis. The study provides valuable insight to selectively reduce spores of undesirable Bacillus species in the food industry.

Pyoderma Gangrenosum Mimicking Wound Infection after Breast Cancer Surgery.

Postoperative pyoderma gangrenosum (PPG) is rare, and its diagnosis is often delayed because of its wound infection-mimicking course. A 53-year-old breast cancer patient who underwent breast-conserving surgery of the right breast presented with fever, leukocytosis, C-reactive protein elevation, and redness of the right breast on postoperative day (POD) 3. The breast wound showed desquamation with painful ulcerative changes from POD 6, and fever was sustained under antibiotic administration. Wound irrigation was attempted; however, inflammatory skin damage progressed to involvement of the entire skin overlying the breast. With clinical suspicion of PPG, skin biopsy and systemic corticosteroid initiation were performed on POD 12. Wound damage progression ceased, and the systemic inflammation subsided. The patient underwent split-thickness skin grafting under intravenous corticosteroid administration, and the wound healed after 30 days. PPG is a rare clinical scenario. Early diagnosis is critical to avoid unnecessary treatment and aggravation of the surgical wound.

Chia seed-assisted separation and detection of polyvinyl chloride microplastics in water via gas chromatography mass spectrometry.

Chia seeds were used to significantly improve the separation efficiency of polyvinyl chloride (PVC) microplastics from water samples via centrifugation. Upon hydration, the mucilage of chia seeds were able to capture PVC microplastics with sizes ranging from tens to hundreds of micrometers. Since PVC microplastics contained di-2-etylhexyl phthalate (DEHP) as a plasticizer (verified via Fourier transform infrared spectrometry), DEHP was used as an indicator in the subsequent quantification via gas chromatography - mass spectrometry (GC-MS) analysis. Specifically after verifying the DEHP peak in the GC spectrum using DEHP reference standard as a positive control, the GC spectral area of that peak was used to quantify the amount of DEHP in the sample. Using nominal operation settings at 10 min and 1000 rpm with 100 mg of chia seeds, the separation efficiency could be improved by 5 times (500%) as compared to the absence of chia seeds. Furthermore, chia seeds were also compatible with simulated synthetic wastewater samples. Most importantly, the use of chia seeds did not interfere with GC-MS quantification protocol and accuracy. The result suggested the proposed method can be used as a simple screening tool of microplastics entering wastewater treatment plant, even though a series of follow-up studies are needed in future.

Development of non-equilibrium rapid replacement aptamer assay for ultra-fast detection of phthalic acid esters.

In this paper, we developed a non-equilibrium rapid replacement aptamer (NERRA) assay that performed ultra-fast (in 30 s) quantitative detection of phthalic acid esters (PAEs) without waiting for the reaction to reach equilibrium. NERRA assay employed fluorescence PoPo3 dye intercalated in an ssDNA aptamer to selectively detect and quantify the PAEs in water. As the intercalated dye was replaced by the PAEs and quenched in the water, the rate of fluorescence change became proportional to PAEs concentration. The sensitivity of NERRA assay was first evaluated with a commercial spectrofluorometer. The selectivity for PAE mixture, individual PAEs, and non-phthalate compounds were also investigated. NERRA assay was also able to quantitatively detect the PAEs in a common plastic product (picnic mat), and the results were compared with those of gas chromatography mass spectrometry. Finally, a custom analyzer (8.5 cm × 8.5 cm × 16.5 cm) was built to demonstrate the portability of the NERRA assay. Using a commercial spectrofluorometer, NERRA assay was able to quantitatively detect a PAE mixture in 30 min with an LOQ of 0.1 µg/L. Using the portable custom analyzer, the detection time was shortened to 30 s with a tradeoff in the LOQ (1 µg/L). In both cases, the LOQs remain within the environmentally relevant PAE concentrations of 0.1-1472 µg/L.

Detection of Nonylphenol with a Gold-Nanoparticle-Based Small-Molecule Sensing System Using an ssDNA Aptamer.

Endocrine-disrupting chemicals (EDCs) threaten many kinds of life throughout the world. These compounds function the same as sexual hormones, inducing precocious puberty, gynecomastia, etc., in the human body. To prevent excess exposure to nonylphenol (NP), a simple and rapid detection system is needed. In this study, we develop a nonylphenol-specific aptamer from a random single-stranded DNA library and test a rapid sensor system based on the aptamer and gold nanoparticles (AuNPs). The aptamer was screened by a methodology involving reduced graphene oxide (rGO). As a result of screening and sequencing, a DNA aptamer was developed that recognizes the target with high binding affinity (Kd = 194.2 ± 65.9 nM) and specificity. The sensor system developed using the aptamer and gold nanoparticles is sensitive (LOD = 2.239 nM). Circular dichroism (CD) spectrometry results show that the free aptamer binds to the target molecule. The aptamer was characterized using gold nanoparticles to measure UV absorbance. Our results suggest that the sensor system developed using this aptamer is useful for field diagnosis of small molecules.

Pridopidine stabilizes mushroom spines in mouse models of Alzheimer's disease by acting on the sigma-1 receptor.

There is evidence that cognitive decline in Alzheimer's disease (AD) results from deficiencies in synaptic communication (e.g., loss of mushroom-shaped 'memory spines') and neurodegenerative processes. This might be treated with sigma-1 receptor (S1R) agonists, which are broadly neuroprotective and modulate synaptic plasticity. For example, we previously found that the mixed muscarinic/S1R agonist AF710B prevents mushroom spine loss in hippocampal cultures from APP knock-in (APP-KI) and presenilin-1-M146 V knock-in (PS1-KI) mice. We also found that the "dopaminergic stabilizer" pridopidine (structurally similar to the S1R agonist R(+)-3-PPP), is a high-affinity S1R agonist and is synaptoprotective in a mouse model of Huntington disease. Here we tested whether pridopidine and R(+)-3-PPP are synaptoprotective in models of AD and whether this requires S1R. We also examined the effects of pridopidine on long-term potentiation (LTP), endoplasmic reticulum calcium and neuronal store-operated calcium entry (nSOC) in spines, all of which are dysregulated in AD, contributing to synaptic pathology. We report here that pridopidine and 3-PPP protect mushroom spines from Aß42 oligomer toxicity in primary WT hippocampal cultures from mice. Pridopidine also reversed LTP defects in hippocampal slices resulting from application of Aß42 oligomers. Pridopidine and 3-PPP rescued mushroom spines in hippocampal cultures from APP-KI and PS1-KI mice. S1R knockdown from lenti-viral shRNA expression destabilized WT mushroom spines and prevented the synaptoprotective effects of pridopidine in PS1-KI cultures. Knockout of PS1/2 destabilized mushroom spines and pridopidine was unable to prevent this. Pridopidine lowered endoplasmic reticulum calcium levels in WT, PS1-KO, PS1-KI and PS2 KO neurons, but not in PS1/2 KO neurons. S1R was required for pridopidine to enhance spine nSOC in PS1-KI neurons. Pridopidine was unable to rescue PS1-KI mushroom spines during pharmacological or genetic inhibition of nSOC. Oral pridopidine treatment rescued mushroom spines in vivo in aged PS1-KI-GFP mice. Pridopidine stabilizes mushroom spines in mouse models of AD and this requires S1R, endoplasmic reticulum calcium leakage through PS1/2 and nSOC. Thus, pridopidine may be useful to explore for the treatment of AD.

Impact of blinking on ocular surface and tear film parameters.

PURPOSE: To investigate the influence of blinking on tear film parameters, ocular surface characteristics, and dry eye symptomology. METHODS: A total of 154 participants were recruited in an age, gender and ethnicity-matched cross-sectional study, of which 77 exhibited clinically detectable incomplete blinking, and 77 did not. Blink rate, dry eye symptomology, tear film parameters, and ocular surface characteristics were assessed in a single clinical session. RESULTS: Overall, a higher proportion of participants exhibiting incomplete blinking fulfilled the TFOS DEWS II dry eye diagnostic criteria (64% versus 44%, p = 0.02), with an odds ratio (95% CI) of 2.2 (1.2-4.2) times. Participants exhibiting incomplete blinking had higher Ocular Surface Disease Index scores (18 ±â€¯13 versus 12 ±â€¯9, p = 0.01), and greater levels of meibomian gland dropout (41.3 ±â€¯15.7% versus 27.5 ±â€¯14.1%, p < 0.001). Furthermore, poorer tear film lipid layer thickness, non-invasive tear film stability, expressed meibum quality, eyelid notching, and anterior blepharitis grades were also observed in those exhibiting incomplete blinking (all p < 0.05). Blink frequency did not correlate significantly with any ocular surface parameters (all p > 0.05). CONCLUSIONS: Incomplete blinking was associated with a two-fold increased risk of dry eye disease. The greater levels of meibomian gland dropout, as well as poorer expressed meibum quality and tear film lipid layer thickness, observed would suggest that incomplete blinking may predispose towards the development of evaporative dry eye.

Exploring the Predisposition of the Asian Eye to Development of Dry Eye.

PURPOSE: To investigate the influence of eyelid shape on tear film quality, ocular surface characteristics and dry eye symptomatology by comparing Asian and Caucasian populations. METHODS: Seventy-four age-matched participants were recruited in a cross-sectional study. Participants were classified into Asian single lid (ASL), Asian double lid (ADL), and Caucasian double lid (CDL) groups. Dry eye symptomatology, ocular surface characteristics, and tear film quality were evaluated in a single clinical session. RESULTS: Meibomian gland dropout was significantly greater in both the ASL and ADL groups than in the CDL group (all P<.05). A greater proportion of ASL and ADL participants exhibited incomplete blinking than CDL patients (all P<.05). There were no significant differences in tear film quality and dry eye symptomatology between the three groups (all P>.05). Exposed ocular surface area, lissamine green staining, and lid wiper epitheliopathy were significantly greater in the ADL group compared to the CDL group (all P<.05). The CDL group displayed significantly greater anterior blepharitis and lid telangiectasia grades compared to both ASL and ADL groups (all P<.05). CONCLUSIONS: A higher degree of meibomian gland dropout and incomplete blinking was observed in both Asian groups compared to the Caucasian group, potentially predisposing these groups to dry eye.

Preparation of a cyanine-based fluorescent probe for highly selective detection of glutathione and its use in living cells and tissues of mice.

Glutathione (GSH) is a major endogenous antioxidant that has a central role in cellular defense against toxins and free radicals. This protocol describes the preparation of CPDSA, a cyanine-based near-infrared (NIR) fluorescent probe for the detection of GSH in cells and in vivo. CPDSA is prepared with high yield through a simple two-step process. The first step is to react commercially available IR-780 iodide with excess anhydrous piperazine in anhydrous N,N-dimethyl formamide at 85 °C to form cyanine-piperazine (CP). The second step is the sulfonylation of CP with dansyl chloride in anhydrous dichloromethane. CPDSA selectively detects GSH in cells, and it has been shown to not react with other biothiols such as cysteine (Cys) and homocysteine (Hcy). This probe can also be used to monitor the GSH level of mouse bone marrow-derived neutrophils (BMDNs). The preparation of probe CPDSA takes 2 d, and experiments in cells and mice take 12-13 d.