An Efficient UPLC-MS/MS Method for the Determination of Pyrroloquinoline Quinone in Rat Plasma and Its Application to a Toxicokinetic Study.

Pyrroloquinoline quinone (PQQ) is a powerful antioxidant coenzyme existing in diet, benefiting growth, development, cognition function, and the repair of damaged organs. However, a method for detecting PQQ in vivo was rarely described, limiting the research on the bioanalysis and metabolic properties of PQQ. In this study, a novel, simple, and efficient ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to quantify the concentration of PQQ in rat plasma. Detection through mass spectrometry was operated by multiple reaction monitoring (MRM) in negative electrospray ionization mode with ion transitions m/z 328.99→197.05 for PQQ and m/z 280.04→195.04 for the internal standard. The calibration curves were linear up to 10,000 ng/mL, with a lower limit of quantitation of 10 ng/mL. Inter-run and intra-run precision ranged from 1.79% to 10.73% and accuracy ranged from -7.73% to 7.30%. The method was successfully applied to a toxicokinetic study in Sprague-Dawley rats after the oral administration of PQQ disodium salt at doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg. The toxicokinetic parameters were subsequently analyzed, which may provide valuable references for the toxicokinetic properties and safety evaluation of PQQ.

Comparative Pharmacokinetic Study of Forchlorfenuron in Adult and Juvenile Rats.

Forchlorfenuron (CPPU) is a plant growth regulator extensively used in agriculture. However, studies on CPPU pharmacokinetics are lacking. We established and validated a rapid, sensitive, and accurate liquid chromatography-mass spectrometry method for CPPU detection in rat plasma. CPPU pharmacokinetics was evaluated in adult and juvenile rats orally treated with 10, 30, and 90 mg/kg of the compound. The area under the plasma drug concentration-time curve from 0 to 24 h (AUC), at the final time point sampled (AUC0-t), and the maximum drug concentration of CPPU increased in a dose-dependent manner. The pharmacokinetic parameters AUC0-t and absolute bioavailability were higher in the juvenile rats than in adult rats. The mean residence time and AUC0-t of juvenile rats in the gavage groups, except for the 10 mg/kg dose, were significantly higher in comparison to those observed for adult rats (p < 0.001). The plasma clearance of CPPU in juvenile rats was slightly lower than that in the adult rats. Taken together, juvenile rats were more sensitive to CPPU than adult rats, which indicates potential safety risks of CPPU in minors.

Simultaneous Quantification and Pharmacokinetic Study of Five Homologs of Dalbavancin in Rat Plasma Using UHPLC-MS/MS.

Dalbavancin is a novel semisynthetic glycopeptide antibiotic that comprises multiple homologs and isomers of similar polarities. However, pharmacokinetic studies have only analyzed the primary components of dalbavancin, namely B0 and B1. In this study, an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to simultaneously determinate and investigate the five homologous components of dalbavancin, namely, A0, A1, B0, B1, and B2, in rat plasma. In this method, methanol was used to precipitate plasma, and a triple-bonded alkyl chromatographic column was used for molecule separation, using 0.1% formic acid-acetonitrile as the mobile phase for gradient elution. Targeted homologs were analyzed by a triple quadrupole mass spectrometer using positive electrospray ionization in multiple reaction monitoring mode. The linearity range was 50-2500 ng/mL with a high correlation coefficient (r2 > 0.998). This method was successfully applied in the pharmacokinetic analysis of dalbavancin hydrochloride to investigate dalbavancin components in rats.

Polycarboxyl ionic liquid functionalized Yb-MOFs nanoballs based dual-wavelength responsive photoelectrochemical aptasensor for the simultaneous determination of AFB1 and OTA.

Developing an accurate and precise approach for the simultaneous detection of ochratoxin A (OTA) and aflatoxin B1 (AFB1) is significant for food safety surveillance. Herein, a photoelectrochemical sensing platform was constructed based on polycarboxylic ionic liquid functionalized metal-organic framework integrated with gold nanoparticles (Yb-MOFs@AuNPs). Sulfhydryl functionalized hairpin DNA (hDNA) was immobilized on a Yb-MOFs@AuNPs modified glassy carbon electrode (GCE) surface through Au-S bond. After blocking residual active binding sites with BSA, gold nanoparticles-labeled AFB1 aptamer (AuNPs-Apt 1) and gold nanorods-labeled OTA aptamer (AuNRs-Apt 2) were introduced to construct a photoelectrochemical aptasensor for the simultaneous determination of AFB1 and OTA. Due to the surface plasmon resonance effect and the nanometer size effect of gold nanomaterials, the photoelectrochemical aptasensor can output photocurrent responses as being excited with different wavelengths at 520 nm and 808 nm, respectively. When the AFB1 and OTA concentration in the range of 0.001-50.0 ng mL-1, a good linear relationship between the photocurrent difference (ΔI) before and after recognizing targets and the logarithm of AFB1 or OTA concentration was obtained. The detection limits for AFB1 and OTA were 0.40 pg mL-1 and 0.19 pg mL-1, respectively. AFB1 and OTA in corn samples were detected simultaneously by the photoelectrochemical aptasensor.

Abnormal Scanning Patterns Based on Eye Movement Entropy in Early Psychosis.

BACKGROUND: Restricted scan path mode is hypothesized to explain abnormal scanning patterns in patients with schizophrenia. Here, we calculated entropy scores (drawing upon gaze data to measure the statistical randomness of eye movements) to quantify how strategical and random participants were to process image stimuli. METHODS: Eighty-six patients with first-episode schizophrenia (FES), 124 individuals at clinical high risk (CHR) for psychosis, and 115 healthy controls (HCs) completed an eye-tracking examination for freely viewing 35 static images (each presented 10s) and cognitive assessments. We compared the group differences in overall entropy score, as well as entropy scores under various conditions. Furthermore, we also investigated the correlation between entropy scores and symptoms along with cognitive function. RESULTS: Increased overall entropy scores were noted in FES and CHR groups relative to HCs, and these differences were already apparent within 0∼2.5s. In addition, the CHR group exhibited higher entropy when viewing low-meaning images compared to HCs. Moreover, the entropy within 0∼2.5s showed significant correlations with negative symptoms in the FES group, Attention/Vigilance scores in the CHR group, as well as Speed of processing and Attention/Vigilance scores across all three groups. CONCLUSIONS: The results indicate that FES and CHR individuals scan pictures more randomly and less strategically than HCs. These patterns also correlate with clinical symptoms and neurocognition. The present study highlights the potential of the eye movement entropy measure as a neurophysiological marker for early psychosis.

Eye Movement Characteristics for Predicting a Transition to Psychosis: Longitudinal Changes and Implications.

BACKGROUND AND HYPOTHESIS: Substantive inquiry into the predictive power of eye movement (EM) features for clinical high-risk (CHR) conversion and their longitudinal trajectories is currently sparse. This study aimed to investigate the efficiency of machine learning predictive models relying on EM indices and examine the longitudinal alterations of these indices across the temporal continuum. STUDY DESIGN: EM assessments (fixation stability, free-viewing, and smooth pursuit tasks) were performed on 140 CHR and 98 healthy control participants at baseline, followed by a 1-year longitudinal observational study. We adopted Cox regression analysis and constructed random forest prediction models. We also employed linear mixed-effects models (LMMs) to analyze longitudinal changes of indices while stratifying by group and time. STUDY RESULTS: Of the 123 CHR participants who underwent a 1-year clinical follow-up, 25 progressed to full-blown psychosis, while 98 remained non-converters. Compared with the non-converters, the converters exhibited prolonged fixation durations, decreased saccade amplitudes during the free-viewing task; larger saccades, and reduced velocity gain during the smooth pursuit task. Furthermore, based on 4 baseline EM measures, a random forest model classified converters and non-converters with an accuracy of 0.776 (95% CI: 0.633, 0.882). Finally, LMMs demonstrated no significant longitudinal alterations in the aforementioned indices among converters after 1 year. CONCLUSIONS: Aberrant EMs may precede psychosis onset and remain stable after 1 year, and applying eye-tracking technology combined with a modeling approach could potentially aid in predicting CHRs evolution into overt psychosis.

Wearable electrochemical sensor based on bimetallic MOF coated CNT/PDMS film electrode via a dual-stamping method for real-time sweat glucose analysis.

Non-invasive wearable sweat glucose sensors are expected to be highly desirable for personalized diabetes management. Therefore, developing facile, convenient, and scalable manufacturing method of such wearable sensors is urgently needed. Herein, we report a simple and low-cost stamping-vacuum filtration dry transfer (SVFDT) method for construction of a wearable sweat glucose electrochemical sensor. In this patch, a three-electrode array template was made by using a polyvinyl chloride (PVC) stamp, followed by the preparation of multiwalled carbon nanotubes (MWCNTs)/polydimethylsiloxane (PDMS) (MP) film electrode using the vacuum-filtration dry transfer method. In addition, for further enhancing the conductivity of the electrode, another similar stamp with a raised surface dipping carbon nanotubes (CNTs) conductive coating was stamped on the surface of the MP electrode to obtain CNTs/MWCNTs/PDMS (CMP) electrode. CMP electrode was modified with the enzyme-like Ni-Co metal-organic framework (MOF) material which showed good electro-catalytic activity and achieved high sensitivity for glucose detection with a low detection limit of 6.78 µM and a wide linear range of 20 µM - 1.1 mM. More importantly, the Ni-Co MOF modified CMP (NCMP) electrode also displayed high stability under stretching and bending conditions. Finally, the sweat absorbent cloth was combined with the NCMP film electrode to form a wearable flexible electrochemical sensor patch, which could adhere to the skin to enrich sweat and realize real-time detection of sweat glucose with high accuracy. This SVFDT method can also be applied to the fabrication of other electronic devices.

Safety Evaluation of Curcumol by a Repeated Dose 28-Day Oral Exposure Toxicity Study in Rats.

Curcumol, a natural product isolated from the traditional Chinese medicine Rhizoma curcumae, possesses various potential therapeutic values in many diseases. However, evidence of its toxicological profile is currently lacking. In this study, a repeated toxicity study of curcumol was conducted for the first time. SD rats were exposed to doses of 250, 500, 1000 mg/kg in a selected dose formulation for 28 days through oral administration. The potential toxic effects of curcumol on the blood system were observed and further validated in vivo and in vitro. Moreover, other hematology and biochemistry parameters as well as the weight of organs were altered, but no related histopathological signs were observed, indicating these changes were not regarded as toxicologically relevant. Our current findings provide a complete understanding of the safety profile of curcumol, which may contribute to its further study of investigational new drug application.

Dissipation behavior, residue dynamics, and dietary risk assessment of forchlorfenuron in postharvest kiwifruits during simulated cold chain logistics and store shelf life.

Forchlorfenuron (CPPU) is often applied during the cultivation of kiwifruit to produce larger fruit. To address degradation patterns of CPPU during simulated cold chain logistics and simulated shelf life of the fruit after harvest, appropriate storage methods and safe consumption behavior can be investigated. In this study, an ultra-high-performance liquid chromatography-tandem mass spectrometry method was adopted to detect CPPU residues under different conditions. CPPU in kiwifruit stored at 6 °C had a half-life of 40.8-77.0 days. However, when kiwifruit was stored at 0 °C under simulated cold chain storage conditions, the half-life of CPPU was 63.0-115.5 days, implying that lower storage temperatures can reduce the degradation rate of CPPU. The residues of CPPU in kiwifruit pulp declined with time, and the reduction followed the first-order kinetics equation. More CPPU residues were present in the pulp of postharvest kiwifruit treated with exogenous ethylene than in the pulp of untreated kiwifruit. Thus, using exogenous ethylene for artificial ripening after harvest is not recommended. We determined that the appropriate cold chain storage temperature is 6 °C. It is recommended that the public select kiwifruit stored for at least 2 weeks. The estimated chronic and acute dietary risk quotients of CPPU are ≤ 0.79% and ≤ 0.11%, respectively. Therefore, it is highly unlikely that consumers will be poisoned by CPPU due to kiwifruit consumption. Our results provide scientific evidence regarding the adoption of appropriate kiwifruit storage methods and consumption behavior to enhance consumption safety.

Prevalence of flexible flatfoot in Taiwanese school-aged children in relation to obesity, gender, and age.

The objective of this study was to determine the prevalence of flexible flatfoot in elementary school children in Taiwan and evaluate the relationship between flatfoot and obesity, gender, and age. A sample of 2,083 children, between 7 and 12 years of age from public elementary schools in northern Taiwan was analyzed. Children were stratified into groups according to age: 7, 8, 9, 10, 11, or 12 years old. Demographic information was obtained, and the presence of flatfoot determined by footprint analysis and grading according to Denis flatfoot staging. A total of 1,222 (59%) children were documented with flatfoot. The incidence percentages of flatfoot were: 67% of males, 49% of females, and 75%, 65%, 57%, and 48% of obese, overweight, normal weight, and underweight children, respectively. A preponderance of flatfoot was observed among 8-year-olds. Multivariate analyses indicated that 8- and 9-year-olds were 1.52 and 0.72 times more likely to have flatfoot than 7-year-olds. Males were twice as likely to have flatfoot as females. Children who were obese or overweight were 2.66 and 1.39 times more likely to have flatfoot than those of average weight. The results of this study indicate that the prevalence of flexible flatfoot is highest among males who are obese and overweight, particularly in the age range of 7 to 8 years.

Effects of prepubertal exposure to forchlorfenuron through prenatal and postnatal gavage administration in developing Sprague-Dawley rats.

Forchlorfenuron (CPPU), a plant growth regulator, is widely used in agriculture. However, its long-term exposure effects on humans, especially neonates, remain unclear. Therefore, we investigated the developmental toxicity of prenatal and postnatal gavage administration of CPPU in rats. Pregnant Sprague-Dawley rats were administered 300 mg/kg/day CPPU by gavage from day 6 of gestation to the cessation of nursing. During weaning, rat offspring were administered 0, 30, 100, or 300 mg/kg/day CPPU for 4 weeks, followed by a 4-week CPPU-free recovery period. There were no significant differences in clinical symptoms, body weight, development indicators, serum biochemical parameters, sex hormone levels, sperm motility, relative organ weights, and histopathological changes among the 0-100 mg/kg/day CPPU groups. In the 300 mg/kg/day CPPU group, female rats exhibited decreased body weight, earlier time of vaginal opening (VO) and first estrus time (FE), elevated estradiol and blood urea nitrogen (BUN) levels, and upregulation of estrogen receptor 1 gene expression, whereas male rats only exhibited increases in serum BUN, creatinine, and glucose levels. Most changes were reversed after the recovery period. Furthermore, the endometrial epithelial height was significantly increased in female rats despite the absence of significant changes in uterine wall thickness and endometrial glands. Thus, CPPU may promote estradiol secretion, resulting in altered VO and FE and adverse effects in prepubertal female rats. These findings may be applied for risk assessment following CPPU exposure in humans.

Characterization of a chitin-glucan complex from the fruiting body of Termitomyces albuminosus (Berk.) Heim.

Chitin-glucan complex (CGC), the main component of fungal cell wall, is reported to have wide applications in the food and pharmaceutical industries because of its physical and physiological activities. In this study, CGC was extracted from the fruiting body of Termitomyces albuminosus (Berk.) Heim with the treatments of deproteination, demineralization and depigmentation to obtain a yield of 13.46%, and its properties were investigated. The results indicated that CGC from T. albuminosus contained glucan and chitin in a molar ratio of 46:54, with very low contents of proteins and inorganic salts. The chitin in CGC was in the α-form, with crystallinity index of 64.81% and degree of acetylation of 65.40%. The surface morphology of CGC was dense and firm with no nanofibers and nanopores as observed by scanning electron microscopy, and the peak degradation temperature was determined to be 314.88 °C. This study suggested that CGC from T. albuminosus was promising to be an alternative source of crustacean chitinous products in the industry of food, medicine, waste water treatment and so on in the future.

Isolation, molecular characterization and antioxidant activity of a water-soluble polysaccharide extracted from the fruiting body of Termitornyces albuminosus (Berk.) Heim.

A water-soluble polysaccharide WSP1 was extracted from the fruiting body of Termitornyces albuminosus. Its molecular weight, monosaccharide composition and molecular structure were determined by GPC, GC-MS, UV spectroscopy, FT-IR spectroscopy, methylation analysis, NMR (1D and 2D) and AFM. Moreover, the antioxidant activity of WSP1 was evaluated in vitro by the tests of reducing power, scavenging ability on DPPH radical and hydroxyl radical, and chelating ability on ferrous ion. The results indicated that the molecular weight of WSP1 was 9 kDa, and it was mainly composed of fucose and galactose in a molar ratio of 1:3.09. Based on monosaccharide composition, methylation analysis and NMR, the possible repeating unit of WSP1 was presented as follows: →2-α-l-Fucp-1→ (6-α-d-Galp-1)3→. The antioxidant assay revealed that, in the concentration range tested in this experiment, WSP1 had strong scavenging ability on DPPH radical, suggesting that WSP1 could be potentially used as a powerful radical scavenger.

Bitter melon (Momordica charantia L.) inhibits adipocyte hypertrophy and down regulates lipogenic gene expression in adipose tissue of diet-induced obese rats.

Bitter melon (Momordica charantia; BM) has been shown to ameliorate diet-induced obesity and insulin resistance. To examine the effect of BM supplementation on cell size and lipid metabolism in adipose tissues, three groups of rats were respectively fed a high-fat diet supplemented without (HF group) or with 5 % lyophilised BM powder (HFB group), or with 0.01 % thiazolidinedione (TZD) (HFT group). A group of rats fed a low-fat diet was also included as a normal control. Hyperinsulinaemia and glucose intolerance were observed in the HF group but not in HFT and HFB groups. Although the number of large adipocytes (>180 microm) of both the HFB and HFT groups was significantly lower than that of the HF group, the adipose tissue mass, TAG content and glycerol-3-phosphate dehydrogenase activity of the HFB group were significantly lower than those of the HFT group, implying that BM might reduce lipogenesis in adipose tissue. Experiment 2 was then conducted to examine the expression of lipogenic genes in adipose tissues of rats fed low-fat, HF or HFB diets. The HFB group showed significantly lower mRNA levels of fatty acid synthase, acetyl-CoA carboxylase-1, lipoprotein lipase and adipocyte fatty acid-binding protein than the HF group (P < 0.05). These results indicate BM can reduce insulin resistance as effective as the anti-diabetic drug TZD. Furthermore, BM can suppress the visceral fat accumulation and inhibit adipocyte hypertrophy, which may be associated with markedly down regulated expressions of lipogenic genes in the adipose.