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Background: As prostaglandin medications, crucial in glaucoma treatment, become more widely used, their local adverse events are increasingly observed., Objectives: To evaluate the common adverse events of four clinically commonly used prostaglandin F (FP) receptor agonists in the treatment of glaucoma in the Food and Drug Administration Adverse Event Reporting System (FAERS) database., Design: We screened and analyzed the generic and brand names of latanoprost, bimatoprost, travoprost, and tafluprost in the FAERS database and summarized and cleaned the baseline information of subjects receiving the above-mentioned drugs., Methods: Perform descriptive statistical analysis on the baseline information of subjects using the drugs. Conduct disproportionality analysis of drug-related adverse events. The criteria for positive signals of adverse events are established by simultaneously meeting the thresholds set by four methods: the ratio of reported odds, proportional reporting ratio, Bayesian confidence propagation neural network, and multi-item gamma Poisson shrinker. Additionally, assess the cumulative risk curves for drug-induced time of the aforementioned drugs and use one-way ANOVA to compare differences in drug-induced time across different groups., Results: The study included 1567 latanoprost, 1517 bimatoprost, 696 travoprost, and 82 tafluprost subjects. Adverse events mainly affected eye disorders, with significant issues in iris hyperpigmentation, ocular pemphigoid, corneal endothelial cell loss, periorbital fat atrophy, corneal irritation, eyelash growth, and ocular hyperemia. The time to onset varied among drugs, with latanoprost showing the longest (mean days = 344.37) and bimatoprost the shortest duration (mean days = 155.65; p  < 0.001)., Conclusion: Although signal detection analysis based on the FAERS database cannot establish a definitive causal relationship, our study found that FP receptor agonists used in glaucoma can cause various adverse events. Assessing their clinical suitability and potential side effects is crucial for providing personalized treatment and ensuring medication safety., (© The Author(s), 2024.)

Background: Hepatocellular carcinoma (HCC) is a major health challenge with high incidence and poor survival rates in China. Systemic therapies, particularly tyrosine kinase inhibitors (TKIs), are the first-line treatment for advanced HCC, but resistance is common. The Rho GTPase family member Rho GTPase activating protein 12 (ARHGAP12), which regulates cell adhesion and invasion, is a potential therapeutic target for overcoming TKI resistance in HCC. However, no studies on the expression of ARHGAP12 in HCC and its role in resistance to TKIs have been reported., Aim: To unveil the expression of ARHGAP12 in HCC, its role in TKI resistance and its potential associated pathways., Methods: This study used single-cell RNA sequencing (scRNA-seq) to evaluate ARHGAP12 mRNA levels and explored its mechanisms through enrichment analysis. CellChat was used to investigate focal adhesion (FA) pathway regulation. We integrated bulk RNA data (RNA-seq and microarray), immunohistochemistry and proteomics to analyze ARHGAP12 mRNA and protein levels, correlating with clinical outcomes. We assessed ARHGAP12 expression in TKI-resistant HCC, integrated conventional HCC to explore its mechanism, identified intersecting FA pathway genes with scRNA-seq data and evaluated its response to TKI and immunotherapy., Results: ARHGAP12 mRNA was found to be highly expressed in malignant hepatocytes and to regulate FA. In malignant hepatocytes in high-score FA groups, MDK-[integrin alpha 6 (ITGA6) + integrin β-1 (ITGB1)] showed specificity in ligand-receptor interactions. ARHGAP12 mRNA and protein were upregulated in bulk RNA, immunohistochemistry and proteomics, and higher expression was associated with a worse prognosis. ARHGAP12 was also found to be a TKI resistance gene that regulated the FA pathway. ITGB1 was identified as a crossover gene in the FA pathway in both scRNA-seq and bulk RNA. High expression of ARHGAP12 was associated with adverse reactions to sorafenib, cabozantinib and regorafenib, but not to immunotherapy., Conclusion: ARHGAP12 expression is elevated in HCC and TKI-resistant HCC, and its regulatory role in FA may underlie the TKI-resistant phenotype., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: WWOX -related epileptic encephalopathy is an autosomal recessive disorder caused by mutations in the WW-containing oxidoreductase gene, characterized by the onset of refractory seizures in infants. Early-onset epilepsy, electroencephalography abnormalities, and developmental delay or degeneration are the main clinical manifestations. Early death can occur in severe cases. In the present study, a novel variant in WWOX was detected in a patient with epilepsy and his healthy parents., Case Presentation: A 5-month-old boy presented with epilepsy. The main manifestations were intractable seizures, mental and motor retardation and hearing impairment. Subsequent genetic testing revealed the presence of an epilepsy-associated novel mutation: c.991C>A (amino acid change: p.Ser304Tyr) in the WWOX gene. Variants were inherited from parents with healthy phenotypes. Finally, a patient died at 6 months of age., Conclusion: The discovery of novel variants has enriched the existing database of WWOX gene variants and may expand the range of clinical options for treating WWOX -related disorders., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Feng, Li, Zhang, Song, Qin and Wang.)

Purpose: This study aimed to assess the drug risk of drug-related keratitis and track the epidemiological characteristics of drug-related keratitis., Methods: This study analyzed data from the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database from January 2004 to December 2023. A disproportionality analysis was conducted to assess drug-related keratitis with positive signals, and drugs were classified and assessed with regard to their drug-induced timing and risk of drug-related keratitis., Results: A total of 1606 drugs were reported to pose a risk of drug-related keratitis in the FAERS database, and, after disproportionality analysis and screening, 17 drugs were found to significantly increase the risk of drug-related keratitis. Among them, seven were ophthalmic medications, including dorzolamide (reporting odds ratio [ROR] = 3695.82), travoprost (ROR = 2287.27), and brimonidine (ROR = 2118.52), and 10 were non-ophthalmic medications, including tralokinumab (ROR = 2609.12), trazodone (ROR = 2377.07), and belantamab mafodotin (ROR = 680.28). The top three drugs having the highest risk of drug-related keratitis were dorzolamide (Bayesian confidence propagation neural network [BCPNN] = 11.71), trazodone (BCPNN = 11.11), and tralokinumab (BCPNN = 11.08). The drug-induced times for non-ophthalmic medications were significantly shorter than those for ophthalmic medications (mean days, 141.02 vs. 321.96, respectively; P < 0.001). The incidence of drug-related keratitis reached its peak in 2023., Conclusions: Prevention of drug-related keratitis is more important than treatment. Identifying the specific risks and timing of drug-induced keratitis can support the development of preventive measures., Translational Relevance: Identifying the specific drugs related to medication-related keratitis is of significant importance for drug vigilance in the occurrence of drug-related keratitis.

Purpose and Design: This study aimed to evaluate the risk of drug-related dry eye using real-world data, underscoring the significance of tracing pharmacological etiology for distinct clinical types of dry eye., Methods: Analyzing adverse event reports in the Food and Drug Administration Adverse Event Reporting System (FAERS) from January 2004 to September 2023, we employed disproportionality analysis and the Bayesian confidence propagation neural network algorithm. The analysis involved categorizing drugs causing dry eye, assessing risk levels, and conducting segmental assessments based on the time of onset of drug-related dry eye adverse reactions., Results: In the FAERS database, adverse reactions related to dry eye were linked to 1160 drugs. Disproportionality analysis identified 33 drugs with significant risk, notably in ophthalmic (brimonidine, bimatoprost), oncology (tisotumab vedotin, erdafitinib), and other medications (isotretinoin, oxymetazoline). The top three drugs with the highest risk of drug-related dry eye are isotretinoin (Bayesian confidence propagation neural network (BCPNN) = 6.88), tisotumab vedotin (BCPNN = 6.88), and brimonidine (BCPNN = 6.77). Among different categories of drugs, respiratory medications have the shortest mean onset time for drug-related dry eye, averaging 50.99 days. The prevalence skewed towards females (69.9 %), particularly in menopausal and elderly individuals (45-70 years old, mean age 54.7 ± 18.2). Reports of drug-related dry eye adverse reactions showed an annual increase., Conclusion: Informed clinical decision-making is crucial for preventing drug-related dry eye. Assessing the risk of dry eyes associated with both local and systemic medications helps optimize treatment and provide necessary cautionary information., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Uveal melanoma (UM) patients face a significant risk of distant metastasis, closely tied to a poor prognosis. Despite this, there is a dearth of research utilizing big data to predict UM distant metastasis. This study leveraged machine learning methods on the Surveillance, Epidemiology, and End Results (SEER) database to forecast the risk probability of distant metastasis. Therefore, the information on UM patients from the SEER database (2000-2020) was split into a 7:3 ratio training set and an internal test set based on distant metastasis presence. Univariate and multivariate logistic regression analyses assessed distant metastasis risk factors. Six machine learning methods constructed a predictive model post-feature variable selection. The model evaluation identified the multilayer perceptron (MLP) as optimal. Shapley additive explanations (SHAP) interpreted the chosen model. A web-based calculator personalized risk probabilities for UM patients. The results show that nine feature variables contributed to the machine learning model. The MLP model demonstrated superior predictive accuracy (Precision = 0.788; ROC AUC = 0.876; PR AUC = 0.788). Grade recode, age, primary site, time from diagnosis to treatment initiation, and total number of malignant tumors were identified as distant metastasis risk factors. Diagnostic method, laterality, rural-urban continuum code, and radiation recode emerged as protective factors. The developed web calculator utilizes the MLP model for personalized risk assessments. In conclusion, the MLP machine learning model emerges as the optimal tool for predicting distant metastasis in UM patients. This model facilitates personalized risk assessments, empowering early and tailored treatment strategies., (© 2024 The Author(s). Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Objective: To investigate the concern about pollen broadcasting in Chinese population from multiple dimensions and to understand the information about allergic rhinitis (AR) in China by analyzing related factors. Methods: From March 1 to September 30, 2022, a large-scale multi-center cross-sectional survey was conducted based on the Questionnaire Star platform in 21 Chinese hospitals. A total of 7 056 subjects from 7 regions in China: Northeast, North, East, Central, South, Southwest, and Northwest China were included. Basic characteristics (including social demographic characteristics and disease characteristics of AR patients), concern about pollen broadcasting, the willingness of pollen-induced AR (PiAR) patients to receive pollen broadcasting, and the treatment satisfaction rate of AR patients were collected. The chi-square test, multivariate linear regression model, and Logistic regression analysis were used to analyze the concern about pollen broadcasting in the Chinese population and related factors from multiple dimensions. Results: Among 7 056 subjects, 23.02% were concerned about pollen broadcasting. Among 3 176 self-reported AR and 1 019 PiAR patients, 25.60% and 39.16% were concerned about pollen broadcasting, respectively, which was higher than that of non-AR or non-PiAR subjects ( χ 2 value was 21.74 and 175.11, respectively, both P <0.001). Among AR patients, the proportion of spring and autumn allergen-positive patients concerned about pollen broadcasting was higher than that in perennial allergen-positive patients ( χ 2 value was 20.90 and 19.51, respectively, both P <0.001). The proportion of AR patients with asthma, sinusitis, allergic conjunctivitis, and cardiovascular and cerebrovascular diseases was higher than those without complications ( χ 2 value was 50.83, 21.97, 56.78, 7.62, respectively, all P <0.05). The proportion of AR patients in North China who could find pollen broadcasting locally was 31.01%, significantly higher than those in other regions (all P <0.05). Multivariate linear regression model analysis showed that among PiAR patients, those with higher per capita household income and higher AR disease cognition levels had been concerned about pollen broadcasting in the past, and those complicated with allergic conjunctivitis had stronger intention to receive pollen broadcasting (B value was 0.24, 0.13, 0.66, 0.47, respectively, all P <0.05). The higher the disease cognition level of PiAR patients, the stronger their willingness to actively participate in treatment ( R 2 =0.72, P <0.001). Only 18.89% of AR patients felt satisfied with the treatment effect. Logistic regression analysis showed that in AR patients, the treatment satisfaction rate was significantly higher among those concerned about pollen broadcasting compared to those who were not ( OR =1.83, P <0.001). Conclusions: Currently, the dissemination of pollen broadcasting in China is hindered by various factors such as disease cognition level. The treatment satisfaction among AR patients remains unsatisfactory.

Background: Phthalates have been reported to impair fertility in various studies. However, evidence exploring the associations between phthalate metabolites in follicular fluid (FF) and reproductive outcomes is lacking., Objectives: To investigate the associations between phthalate metabolite concentrations in FF and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes among women recruited from a fertility clinic., Methods: We included 641 women undergoing IVF/ICSI treatment from December 2018 to January 2020. The levels of eight phthalate metabolites, including monoethyl phthalate (MEP), mono-isobutyl phthalate (MiBP), mono- n -butyl phthalate (MBP), monobenzyl phthalate (MBzP), mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), were quantified in FF collected on the oocyte retrieval day. Associations between quartiles of individual phthalate metabolite concentrations and nine IVF/ICSI outcomes, including oocyte yield, mature oocyte number, two distinct pronuclei (2PN) zygote number, fertilization rate, blastocyst formation rate, implantation, clinical pregnancy, miscarriage, and live birth, were estimated with generalized linear models. The effects of phthalate mixtures on IVF/ICSI outcomes were assessed using Bayesian kernel machine regression (BKMR) models., Results: After adjusting for relevant confounders, elevated quartiles of MBzP, MEHHP, and MEHP in FF were inversely associated with the numbers of retrieved oocytes, mature oocytes, and 2PN zygotes (all p for trends < 0.10 ). In comparison with the lowest quartile, the highest quartile of molar sum of di(2-ethylhexyl) phthalate metabolites ( Σ DEHP ) was associated with a reduction of 9.1% [95% confidence interval (CI): - 17.1 % , - 0.37 % ] and 10.3% (95% CI: - 18.8 % , - 0.94 % ) in yielded oocyte and mature oocyte numbers, respectively. Furthermore, the BKMR models revealed inverse associations between phthalate mixtures and the numbers of retrieved oocytes and mature oocytes. We generally found null results for implantation, clinical pregnancy, miscarriage, and live birth., Discussion: Certain phthalate metabolites in FF are inversely associated with the numbers of retrieved oocytes, mature oocytes, and 2PN zygotes among women undergoing IVF/ICSI treatment. https://doi.org/10.1289/EHP11998.

As an important fruit pest of global significance, Drosophila suzukii occupies a special ecological niche, with the characteristics of high sugar and low protein contents. This niche differs from those occupied by other fruit-damaging Drosophila species. Gut bacteria substantially impact the physiology and ecology of insects. However, the contribution of gut microbes to the fitness of D. suzukii in their special ecological niche remains unclear. In this study, the effect of Klebsiella oxytoca on the development of D. suzukii was examined at physiological and molecular levels. The results showed that, after the removal of gut microbiota, the survival rate and longevity of axenic D. suzukii decreased significantly. Reintroduction of K. oxytoca to the midgut of D. suzukii advanced the development level of D. suzukii. The differentially expressed genes and metabolites between axenic and K. oxytoca-reintroduced D. suzukii were enriched in the pathways of carbohydrate metabolism. This advancement was achieved through an increased glycolysis rate and the regulation of the transcript level of key genes in the glycolysis/gluconeogenesis pathway. Klebsiella oxytoca is likely to play an important role in increasing host fitness in their high-sugar ecological niche by stimulating the glycolysis/gluconeogenesis pathway. As a protein source, bacteria can also provide direct nutrition for D. suzukii, which depends on the quantity or biomass of K. oxytoca. This result may provide a new target for controlling D. suzukii by inhibiting sugar metabolism through eliminating the effect of K. oxytoca and thus disrupting the balance of gut microbial communities., (© 2023 Institute of Zoology, Chinese Academy of Sciences.)

Many studies have showed that phthalates have reproductive and embryonic toxicity, while the potential mechanisms are mostly unknown. Inflammation may play a mediating part in phthalate exposure and adverse reproductive endpoints. A cross-sectional survey was conducted to investigate the associations of phthalate metabolites with inflammatory cytokines in the follicular fluid (FF) of women undergoing in vitro fertilization (IVF). We determined the levels of eight phthalate metabolites and five cytokines in the FF of 76 women, including interleukin (IL)- 6, IL-8, IL-10, monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α). The associations of individual phthalate exposure with cytokines in FF samples were explored by multiple linear regression. We further evaluated the combined effects of multiple phthalate exposures on FF levels of cytokines by using Bayesian kernel machine regression (BKMR) models. We found that there was a positive relationship between mono-ethyl phthalate (MEP) and IL-6 in the FF (percent change:12.4%; 95% CI: 1.3%, 24.9%). In contrast, elevated mono-benzyl phthalate (MBzP), mono(2-ethylhexyl) phthalate (MEHP) and %MEHP levels were associated with decreased MCP-1. In the BKMR models, phthalate metabolite mixtures were positively associated with TNF-α when the mixtures were lower than 65th percentile compared with their medians. In the stratified analyses, MEHP was inversely associated with MCP-1 among women with BMI ≥ 23 kg/m 2 (test for interaction <0.05). Our results suggest that certain phthalate metabolites or their mixtures may alter levels of inflammatory cytokines in the FF, and further research is necessary to elucidate the mechanisms underlying the relationship between phthalates exposure, ovarian dysfunction and adverse pregnancy outcomes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Phthalates are widespread endocrine disrupting chemicals that adversely affect female reproductive health. We aimed to investigate the individual and joint associations of phthalate exposures measured by repeated urinary metabolites with polycystic ovary (PCO) and polycystic ovary syndrome (PCOS) (96 PCO cases, 96 PCOS cases and 370 controls). In single-pollutant analyses, mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP) and the sum of di(2-ethylhexyl) phthalate (∑DEHP) were associated with increased prevalence of PCO. Mono(2-ethylhexyl) phthalate (MEHP), MBzP and ∑DEHP were associated with elevated prevalence of PCOS. In multiple-pollutant analyses, one-quartile increase of weighted quantile sum index in phthalate metabolite mixtures was associated with increased prevalence of PCO and PCOS, and MBzP was the most major contributor. Our findings suggest a potential role for phthalate exposures, both individually and in mixtures, in the development of PCO and PCOS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Epidemiological studies on phthalate exposures in associations with uterine fibroids (UF) and endometriosis (EMT) are inconsistent. The underlying mechanisms are poorly understood., Objectives: To investigate the relationships of urinary phthalate metabolites with UF and EMT risks, and further to examine the mediating role of oxidative stress., Methods: This study included 83 and 47 women separately diagnosed with UF and EMT, as well as 226 controls from the Tongji Reproductive and Environmental (TREE) cohort. Two spot urine samples from each woman were analyzed for two oxidative stress indicators and eight urinary phthalate metabolites. Unconditional logistic regression models or multivariate regression models were fitted to evaluate the associations among phthalate exposures, oxidative stress indicators, and the risks of UF and EMT. The potential mediating role of oxidative stress was estimated by the mediation analyses., Results: We observed that each ln-unit increase in urinary mono-benzyl phthalate (MBzP) concentrations was associated with increased UF risk [adjusted OR (aOR): 1.56, 95% CI: 1.20, 2.02], and that each ln-unit increase in urinary MBzP (aOR: 1.48, 95% CI: 1.09, 1.99), mono-isobutyl phthalate (MiBP) (aOR: 1.83, 95% CI: 1.19, 2.82), and mono-2-ethylhexyl phthalate (MEHP) (aOR: 1.66, 95% CI: 1.19, 2.31) concentrations were associated with increased EMT risk (all FDR-adjusted P < 0.05). Moreover, we observed that all tested urinary phthalate metabolites were positively associated with two oxidative stress indicators [4-hydroxy-2-nonenal-mercapturic acid (4-HNE-MA) and 8-hydroxy-2-deoxyguanosine (8-OHdG)], in which 8-OHdG was associated with increased risks of UF and EMT (all FDR-adjusted P < 0.05). The mediation analyses showed that 8-OHdG mediated the positive relationships of MBzP with UF risk, and of MiBP, MBzP, and MEHP with EMT risk, with the estimated intermediary proportion ranging from 32.7% to 48.1%., Conclusions: Oxidatively generated DNA damage may mediate the positive associations of certain phthalate exposures with the risks of UF and EMT. However, further investigation is warranted to confirm these findings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: To investigate whether rescue in vitro maturation (R-IVM) improves the reproductive outcomes among women undergoing intracytoplasmic sperm injection (ICSI) after one oocyte retrieved cycle., Methods: Between January 2019 and December 2020, 2602 women who underwent ICSI in the Reproductive Medicine Center of Tongji Hospital, Wuhan, China, were included in our retrospective cohort study. There were 2112 women undergoing only ICSI and 490 women with R-IVM followed by ICSI. The intermediate reproductive outcomes and pregnancy outcomes were assessed, including the number of normally fertilized embryos, number of cleaved embryos, number of good-quality embryos, number of day-3 available embryos, number of embryos cultured past day-3, number of blastocysts, number of available blastocysts, biochemical pregnancy, miscarriage, clinical pregnancy and live birth. The perinatal outcomes were also assessed, including preterm birth and birth weight. The abovementioned outcomes were also calculated for in vivo matured and R-IVM oocytes separately in women undergoing ICSI with R-IVM group., Results: Compared with the women who underwent only ICSI, those who underwent ICSI with R-IVM had higher numbers of MII oocytes, normally fertilized embryos, cleaved embryos, day-3 available embryos, embryos cultured past day-3, and higher oocyte maturation rate, available embryo rate than women undergoing only ICSI. Additionally, we found that women undergoing ICSI with R-IVM had an increased chance of clinical pregnancy (adjusted OR=1.50, 95% CI: 1.17-1.93) and cumulative live birth (adjusted OR=1.35, 95% CI: 1.07-1.71). After propensity score matching (PSM), the cumulative live birth rate was 60.1% for women undergoing ICSI with R-IVM versus 54.9% for women undergoing only ICSI (OR=1.24, 95% CI: 0.94-1.63). The reproductive outcomes were also significantly different when calculated for in vivo matured and R-IVM oocytes separately in women undergoing ICSI with R-IVM group. All live births from R-IVM embryos were healthy and without malformations or complications., Conclusion: R-IVM may improve the reproductive outcomes of women undergoing ICSI. It may also provide a reference for the safety of R-IVM. This study maybe support a routine application of R-IVM among patients who intend to undergo ICSI., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Qin, Jiang, Yao, Yao, Yuan, Wang, Deng, Du, Ren, Guo and Li.)

Dangefentong Capsules is a new traditional Chinese medicine preparation for the treatment of diabetic peripheral neuropathy. It is based on the Salviae Miltiorrhizae Radix et Rhizoma-Puerariae Lobatae Radix herb pair with salvianolic acids, tanshinones and pueraria flavonoids as main components. Studying the chemical composition in vivo of Dangefentong Capsules and its metabolites is of great significance for making clear its pharmacodynamic material basis and the action mechanism. The UHPLC-Q/Orbitrap-MS/MS was applied to rapidly analyze the metabolites and metabolic pathways of Dangefentong Capsules in Beagle dogs after gavage. Eclipse plus C&#95;(18) column(2.1 mm×50 mm, 1.8 μm) was used, and gradient elution was performed with 0.1% formic acid aqueous solution(A)-formic acid acetonitrile solution(B). A heated electrospray ion source(HESI) was employed. The scanning mode was set as the positive and negative ion mode, and the mass scanning range was m/z 100-1 000. The plasma, urine and feces samples were collected after male Beagle dogs were administered with Dangefentong Capsules. The prototype components and metabolites were identified by UHPLC-Q/Orbitrap-MS/MS analysis combined with reference substances and references. The results showed that 107 chemical components were identified, including 58 prototype components and 49 metabolites. The identified prototype components included 42 components from Salviae Miltiorrhizae Radix et Rhizoma and 16 components from Puerariae Lobatae Radix. The metabolites consist of 21 and 28 metabolites of Salviae Miltiorrhizae Radix et Rhizoma and Puerariae Lobatae Radix, respectively. They are mainly derived from the methylation, hydroxylation, sulfation and glucuronidation of salvianolic acids, tanshinones and pueraria flavonoids. This research rapi-dly analyzes the chemical components in vivo of Beagle dogs administered with Dangefentong Capsules, laying a basis for illustrating the pharmacodynamic material basis and mechanism of Dangefentong Capsules.

Dry eye disease (DED) is one of the most common chronic multifactorial ocular surface diseases with high prevalence and complex pathogenesis. DED results in several ocular discomforts, vision fluctuation, and even potential damage of the ocular surface, bringing heavy burdens both on individuals and the society. The pathology of DED consists of tear film hyperosmolarity and immune responses on the ocular surface. Mice are widely used for developing models that simulate human DED features for investigating its pathogenesis and treatment. DED can be classified into aqueous-deficiency dry eye (ADDE) and evaporative dry eye (EDE). ADDE can be further divided into Sjögren syndrome dry eye (SSDE) and non-Sjögren syndrome dry eye (NSSDE). SSDE mouse models include natural strains, typified by non-obese diabetic (NOD) mice, and genetically engineered ones, like Aire-/- and Id3 knockout mice. Intrinsic EDE mainly refers to meibomian gland dysfunction (MGD). Eda-/- Tabby, Sod1-/- , Elovl1-/- are the most common transgenic MGD mouse models. Transgenic mouse models provide useful tools for studying the pathogenesis of DED and evaluating its novel therapies. This review compares the major transgenic dry eye mouse models and discusses their applications in DED research., (International Journal of Ophthalmology Press.)

Objective: To explore whether peripheral blood CD8(+)T lymphocyte dysfunction is correlated with the programmed death receptor-1 (PD-1) expression in patients with acute-on-chronic liver failure (HBV-ACLF). Methods: Peripheral blood mononuclear cells (PBMC) were collected from patients with HBV-ACLF and healthy controls. CD8(+)T lymphocytes number and PD-1 expression condition in CD8(+)T lymphocytes were detected by flow cytometry. CD8(+)T lymphocytes isolated from peripheral blood of HBV-ACLF patients were further cultured in vitro. One group was added with PD-L1-IgG fusion protein (ACLF+PD-1 group), and the other group was added with IgG fusion protein (ACLF group). Proliferation ability (ki67), cell viability (CD69), and secretion ability of effector cytokines (IL-2, IFN-γ, TNF-α) were analyzed. Results: 30 cases with HBV-ACLF and healthy controls were enrolled. CD8(+)T lymphocytes absolute number was significantly lower in the peripheral blood of patients with ACLF group (333.88 ± 147.74)/μl than healthy controls (872.50 ± 206.64)/μl ( P < 0.001). PD-1 expression in peripheral blood CD8(+)T lymphocytes were significantly increased in ACLF group (13.33% ± 2.52%), ( P = 0.027) than healthy controls (7.02% ± 2.12%). In in vitro culture, compared with healthy controls, the peripheral blood CD8(+)T lymphocytes cell viability (CD69), proliferation ability (ki67) (all P ​​< 0.001), and the level of cytokine production (IL-2, IFN-γ, TNF-α) (all P < 0.05) were equally weakened in patients with ACLF group. Compared with ACLF group, CD8(+)T cell viability (CD69), proliferation ability (KI67) (all P < 0.05), and the level of cytokine production were weakened in ACLF+PD-1 group (all P < 0.05). Conclusion: HBV-ACLF patients have CD8(+)T lymphocyte dysfunction. Therefore, PD-1 may have correlation in the regulation of CD8(+)T lymphocyte dysfunction in ACLF patients.

The present study explored the beneficial effect of Dendrobium huoshanense stem polysaccharide (cDHPS) after oral administration on rheumatoid arthritis (RA) using type Ⅱ collagen-induced arthritis (CIA) mouse model. It was found that cDHPS effectively alleviated joint swelling, synovial hyperplasia, pannus formation, cartilage erosion and bone destruction in CIA mice. Concurrently, cDHPS remodeled the balance of Th17 and regulatory T cells, reduced the secretion of pro-inflammatory mediators related to fibroblast-like synoviocyte activation, angiogenesis, articular cartilage degradation and osteoclast differentiation, inhibited HIF-1α expression and promoted anti-inflammatory mediator release in the joint tissues and serum of CIA mice. Western blot of joint tissues showed that cDHPS significantly inhibited the phosphorylation of IκB, p65, JNK, p38, ERK1/2, AKT, PI3K, JAK1 and STAT3 in CIA mice. These results suggest that cDHPS possesses the potential of ameliorating RA and its anti-RA effect may be attributed to the inhibition of inflammatory signaling pathways., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Glucagon-like peptide-1 (GLP-1) secreted from enteroendocrine L-cells is a pleiotropic hormone with beneficial potential related to islet function, diet control, glucose homeostasis, inflammation relief, and cardiovascular protection. The present study aimed at investigating the effect of Polygonatum cyrtonema polysaccharide (PCP) after structural identification on GLP-1 secretion and the possible mechanism involved in the PCP-stimulated secretion of GLP-1. It was found that GLP-1 secretion was effectively promoted ( p < 0.01) by PCP both in rats with oral administration for 5 weeks (13.9 ± 0.3-35.8 ± 0.3 pmol/L) and ileal administration within 2 h (13.6 ± 0.4-34.1 ± 1.1 pmol/L) and in enteroendocrine NCI-H716 cells with direct stimulation within 24 h (2.05 ± 0.3-20.7 ± 0.2 pmol/L). The sweet taste receptor T1R2/T1R3 was identified to be essential for NCI-H716 cells to directly recognize PCP. The intervention experiments showed that PCP-stimulated GLP-1 secretion was significantly depressed ( p < 0.01) not only by antibodies, siRNA, and the inhibitor of T1R2/T1R3 but also by an adenylate cyclase inhibitor. These results suggest that PCP stimulates GLP-1 secretion from enteroendocrine cells possibly through activation of the T1R2/T1R3-mediated cAMP signaling pathway.

The nectarine is an important fruit, which is attacked by Drosophila suzukii in Europe and the United States but there are no reports of it attacking nectarines in China. Here, we determined the oviposition preference of D. suzukii six on intact and sliced nectarine varieties in China and how physical and physiological indexes of the fruit correlate with these preferences. D. suzukii were allowed to oviposit on two early-, two middle- and two late-maturing varieties of nectarine-Shuguang and Chunguang, Fengguang and Zhong you 4, Zhong you 7 and Zhong you 8, respectively and the number of larvae also followed the order. The firmness, soluble solids content and the nutritional components of the amino acid, protein, soluble sugar and pectin contents of each variety were measured. D. suzukii preferred the early Shuguang variety, followed by the early Chunguang variety and then the middle Zhong you 4 and Fengguang varieties. Taken together, results show that D. suzukii shows preferences for earlier rather than later varieties of nectarines in China and that these preferences are related to the fruit's physical and physiological traits. Results suggest that mixed cultivation of early-, middle- and late-maturing nectarine varieties should be avoided in order to prevent fly dispersal and infestation by D. suzukii .

Smart dressings, which show obvious advantage and potential in wound treatment and real-time monitoring, attract widespread attention in recent years. Real-time and dynamic acquiring wound information is vital to the treatment and prognosis of wound. Further research on smart dressings is helpful for wound management, personalized treatment, and realization of medical application translation of health monitoring technology. In the article, we categorize smart dressings and conclude their functions according to the type of micro-environment information of wound gathered by smart dressings.

Chimeric antigen receptor-modified T cells (CAR-T cells) have emerged as a promising cancer immunotherapy for solid tumors. Epithelial cell adhesion molecule (EpCAM) is overexpressed in a variety of tumors and is recognized as a biomarker for circulating tumor cells and cancer stem cells, representing an attractive target for adoptive T-cell immunotherapy. This study generated third-generation CAR-T cells with redirected specificity to EpCAM (EpCAM CAR-T) by lentiviral vector. The study demonstrated that EpCAM CAR-T cells can elicit lytic cytotoxicity to target cells in an EpCAM-dependent manner and secrete cytotoxic cytokines, including interferon gamma and tumor necrosis factor alpha. Furthermore, adoptive transfer of EpCAM CAR-T cells significantly delayed tumor growth and formation in xenograft models. In addition, the safety evaluation showed that CAR-T cells have no systemic toxicity in mice. The data confirmed the antitumor ability and safety of CAR-T cells targeting EpCAM and may provide a new target for CAR-T cell therapies in treating solid tumors.

Objective: To test the killing effect of type Ⅰ receptor tyrosine kinase-like orphan receptor (ROR1) chimeric antigen receptor T cell (CAR-T) on several ROR1-expressing tumor cells in vitro., Methods: The CAR gene was designed and synthesized by constructing the lentiviral vector plasmid, and Bam HⅠ/ Eco RⅠ was used to identify the plasmid. The expression levels of ROR1 among a variety of tumor cell lines were compared using flow cytometry (FCM). The killing effect of CAR-T on positive cells was detected by FCM, the LDH assay and ELISA., Results: The double enzyme digestion identified CAR gene was successfully constructed to the lentivirus vector plasmid. FCM detection showed that the efficiency of CAR-T infection was about 47.23%. Multiple tumor cells expressed ROR1 in varying degrees. The FCM and the LDH assay indicated that CAR-T specifically killed ROR1-positive tumor cells. On positive target cells, more interferonI-γ (FN-γ) could be released during the CAR-T killing process than control T ( P <0.05)., Conclusion: We successfully constructed ROR1 CAR-T. CAR-T can specifically kill ROR1-positive tumor cells and cause the release of large amounts of IFN-γ, providing an experimental basis for clinical application., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Science Edition).)

Chimeric antigen receptor-modified T cells (CAR-T) are endowed with cytotoxic specificity to tumor cells. Although CAR-T-based cancer immunotherapy presents curable therapeutic potential for hematological malignancies, achieving substantial efficacy for solid tumors remain challenging. Researchers have exploited many strategies to enhance the anti-tumor efficacy of CAR-T cells for solid tumors, among which cytokine-armed CAR-T cells improve the proliferation, survival, homing and other properties of CAR-T cells. Interleukins (ILs), pivotal cytokines that affect the function of immune cells, were co-expressed in CAR-T cells or combinatorially administered to enhance the therapeutic potential in clinical trials. In this review, we summarize the strategies exploited by ILs to improve the anti-cancer ability of CAR-T cells and the different impacts of different ILs on CAR-T cells.

Aims and Objectives: To explore the characteristics of mortality among severe stroke patients, analyse their causes of death and provide evidence for improving the survival rate of stroke patients., Background: Stroke is an important fatal and disabling disease that poses a large burden on its patients, and its high death rates have caused substantial concern to the World Health Organization., Design: A retrospective case-control study., Methods: A total of 188 patients who died of stroke in the neurological intensive care unit of the First Affiliated Hospital of Chongqing Medical University from January 2012-December 2015 were selected as cases. Additionally, 188 stroke survivors from the same neurological intensive care unit were randomly selected as paired cases. The clinical characteristics of the severe stroke patient deaths were analysed, and a univariate analysis was conducted to determine potential mortality risk factors. A logistic regression analysis was then conducted to determine the independent risk factors of mortality., Results: We investigated a total of 231 cases of death in neurological intensive care unit patients, 188 of whom died of stroke. Therefore, the death rate from stroke accounted for 81.3% of the total population, with ischaemic, haemorrhagic and mixed strokes accounting for 47.19%, 26.84% and 7.36% of the patients, respectively. The leading cause of death was central nervous system-related causes (central respiratory and circulatory failure, brain herniation), followed by multisystemic causes. The independent risk factors of death among the neurological intensive care unit patients were as follows: brain herniation (OR = 18.15), multiple organ failure (OR = 13.12), dyslipidemia (OR = 4.64), community-acquired lung infection (OR = 4.15), use of mechanical ventilation (OR = 3.37), hypoproteinemia (OR = 2.29), history of hypertension (OR = 2.03) and hospital-acquired pneumonia (OR = 1.75)., Conclusions: The most common cause of death in stroke patients was damage to the central nervous system. Independent risk factors were brain herniation, multiple organ failure, dyslipidemia, community-acquired lung infection, the use of mechanical ventilation, hypoproteinemia, a history of hypertension and hospital-acquired pneumonia. Clinicians should be aware of the presence and possible effects of these conditions. Early prevention, monitoring and intervention to modify controllable risk factors will improve patient prognosis., Relevance to Clinical Practice: Clinicians should be aware of the multiple independent risk factors of death and implement timely treatment measures to reduce the incidence of death in severe stroke patients., (© 2017 John Wiley & Sons Ltd.)

Objective: This study aims to explore the treatment of methicillin-resistant staphylococcus aureus (MRSA) infection by using meta-analysis method., Materials and Methods: Pubmed/Medline, ScienceDirect, CNKI and Wanfang database were comprehensively searched to obtain the randomized controlled trials (RCTs) on linezolid and vancomycin in the treatment of MRSA infections. We extracted features and information of included studies and selected appropriate effect models based on the heterogeneity test results. The funnel plot was used to analyze publication bias., Results: A total of seven RCTs including 5376 cases met the inclusion criteria. Meta-analysis showed that the clinical cure rate of linezolid group was higher than that of vancomycin group after treatment (OR = 1.85; 95% CI: 1.33-2.59, p<0.001) and follow-up (OR = 1.49; 95% CI: 1.17-1.91, p=0.001). In the microbiologically evaluable patients, end of therapy (EOT) MRSA clearance rate, and test of cure (TOC) MRSA clearance rate of linezolid were superior to those of vancomycin., Conclusions: Based on the combined analysis of randomized controlled trials, the efficacy of linezolid should be better than that of vancomycin in the treatment of infections caused by MRSA, but conclusions still need to be further validated by more well-designed RCTs of a large sample.

A novel liquid chromatography tandem mass spectrometry (LCMSMS) method for the quantitative measurement of gut microbial-derived short-chain fatty acids (SCFAs) in human infant stool has been developed and validated. Baseline chromatographic resolution was achieved for 12 SCFAs (acetic, butyric, caproic, 2,2-dimethylbutyric, 2-ethylbutyric, isobutyric, isovaleric, 2-methylbutyric, 4-methylvaleric, propionic, pivalic and valeric acids) within an analysis time of 15min. A novel sequential derivatization of endogenous and spiked SCFAs in stool via 12 C- and 13 C-aniline respectively, facilitated the accurate quantitation of 12 C-aniline derivatized endogenous SCFAs based on calibration of exogenously 13 C-derivatized SCFAs. Optimized quenching of derivatization agents prior to LCMSMS analysis further reduced to negligible levels the confounding chromatographic peak due to in-line derivatization of unquenched aniline with residual acetic acid present within the LCMS system. The effect of residual acetic acid, a common LCMS modifier, in analysis of SCFAs has not been addressed in previous SCFA assays. For the first time, a total of 9 SCFAs (acetic, butyric, caproic, isobutyric, isovaleric, 2-methylbutyric, 4-methylvaleric, propionic and valeric acids) were detected and quantitated in 107 healthy infant stool samples. The abundance and diversity of SCFAs in infant stool vary temporally from 3 weeks onwards and stabilize towards the end of 12 months. This in turn reflects the maturation of infant SCFA-producing gut microbiota community. In summary, this novel method is applicable to future studies that investigate the biological roles of SCFAs in paediatric health and diseases., (Copyright © 2017 Elsevier B.V. All rights reserved.)

T-lymphocytes genetically engineered with the chimeric antigen receptor (CAR-T) have shown great therapeutic potential in cancer treatment. A variety of preclinical researches and clinical trials of CAR-T therapy have been carried out to lay the foundation for future clinical application. In these researches, several gene-transfer methods were used to deliver CARs or other genes into T-lymphocytes, equipping CAR-modified T cells with a property of recognizing and attacking antigen-expressing tumor cells in a major histocompatibility complex-independent manner. Here, we summarize the gene-transfer vectors commonly used in the generation of CAR-T cell, including retrovirus vectors, lentivirus vectors, the transposon/transposase system, the plasmid-based system, and the messenger RNA electroporation system. The following aspects were compared in parallel: efficiency of gene transfer, the integration methods in the modified T cells, foreground of scale-up production, and application and development in clinical trials. These aspects should be taken into account to generate the optimal CAR-gene vector that may be suitable for future clinical application.

T cells, genetically modified by chimeric antigen receptors (CAR-T), are endowed with specificity to a desired antigen and are cytotoxic to cells expressing the targeted antigen. CAR-T-based cancer immunotherapy is a promising therapy for curing hematological malignancy, such as acute lymphoid leukemia, and is promising for extending their efficacy to defeat solid tumors. To date, dozens of different CAR-T cells have been evaluated in clinical trials to treat tumors; this necessitates the establishment of guidelines for the production and application of CAR-T cells. However, it is challenging to standardize CAR-T cancer therapy because it involves a combination of gene therapy and cell therapy. In this review, we compare the existing guidelines for CAR-T cells and discuss the challenges and considerations for establishing guidance for CAR-T-based cancer immunotherapy.

Recent reports on the impressive efficacy of chimeric antigen receptor (CAR)-modified T cells against hematologic malignancies have inspired oncologists to extend these efforts for the treatment of solid tumors. Clinical trials of CAR-T-based cancer immunotherapy for solid tumors showed that the efficacies are not as remarkable as in the case of hematologic malignancies. There are several challenges that researchers must face when treating solid cancers with CAR-T cells, these include choosing an ideal target, promoting efficient trafficking and infiltration, overcoming the immunosuppressive microenvironment, and avoiding associated toxicity. In this review, we discuss the obstacles imposed by solid tumors on CAR-T cell-based immunotherapy and strategies adopted to improve the therapeutic potential of this approach. Continued investigations are necessary to improve therapeutic outcomes and decrease the adverse effects of CAR-T cell therapy in patients with solid malignancies in the future.

Objective: To study the effects of neuronal apoptosis under the induction of β-amyloid inflammatory supernatant., Methods: The neurons were intervened by β-amyloid-induced inflammatory supernatant at the concentration of Aβ1-42 at 125 nmol/L. And the expressions of Bcl-2, caspase-3, PARP and neuronal apoptosis were detected., Results: The caspase-3 (14.2 ± 1.8), Bcl-2 (10.6 ± 0.8) positive cells of microglia inflammatory supernatant stimulated group were significantly elevated than the control (2.2 ± 0.6, 5.0 ± 0.3, P < 0.01). Nuclear chromatin was uniform yellow-green fluorescent. And there was significant difference of neuronal apoptosis between microglia inflammatory supernatant group and Aβ1-42 directly stimulated group., Conclusion: Neuronal apoptosis is induced by caspase-3 in β-amyloid inflammatory supernatant. One of the important causes is chronic inflammatory process of activated microglia by Aβ.

This study demonstrated that pyrrolidine dithiocarbamate (PDTC), a potent nuclear factor-κB inhibitor, showed stronger inhibitory effects on nuclear factor-κB activation in endometriotic stromal cells than in normal endometrial stromal cells as determined by electrophoretic mobility shift assay and Western blot analysis. Pretreatment of endometriotic stromal cells with PDTC attenuated tumor necrosis factor-α-induced expressions of CD44s, matrix metalloproteinase-9, and vascular endothelial growth factor whereas reversed tumor necrosis factor-α-reduced expressions of tissue inhibitor of metalloproteinase-1 revealed by reverse transcriptase polymerase chain reaction and Western blot analysis, suggesting that PDTC may represent a novel therapeutic strategy for treatment of endometriosis., (Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate the efficacy of teacher tablets in the treatment of pharyngitis., Method: One hundred and thirty six patients with acute pharyngitis or chronic pharyngitis in attack were randamly divided into two groups: treated group (n=68), the patients were given teacher tablets for 7 days, control group (n=68), the patients were given Qinlian capsule for 7 days. Before and after the experimental medicine-taking test, general condition, clinical symptoms and features of examinations on laryngo-pharynx, throat swab bacterial culture were measured., Result: After 7 day medicine-taking experiment, teacher tablets can improve clinical symptoms (at an efficacy rate of more than 60%) and features (at an efficacy rate of more than 80%) of laryngopharynx, in treated group, the inhibition ratios of alpha streptococcus, neisseria and staphylococcus aureus are more than 50%. There are no significant difference between treated group and control groups in those detected index., Conclusion: Teacher tablets is effective for pharyagitis.

This study examined the effects of arsenic trioxide on apoptosis and interleukin-4 release in T cells of asthmatic patients in vitro and investigated the role of Bcl-2 in the active mechanism. T cells were isolated from asthmatic patients (n = 21) and healthy controls (n = 20), and then treated with arsenic trioxide and dexamethasone. Cell apoptosis was measured using fluorescence microscopy, flow cytometry and a cytochrome c ELISA kit. Interleukin-4 levels in the serum and in supernatants from T cells were quantified by ELISA. Flow cytometric analysis and immunofluorescence studies were performed to determine Bcl-2 expression. T cells of the asthmatic patients (i. e. without treatment) exhibited decelerated spontaneous apoptosis after 24 h incubation in vitro when compared to T cells of the healthy controls. With dexamethasone treatment, an increase in apoptosis of T cells was not significantly different between both groups, irrespective of the method used. Arsenic trioxide treatment, however, significantly increased the apoptosis of T cells of the asthmatic group and showed a slight effect on the control group. In asthmatic patients, elevated levels of interleukin-4 and up-regulated Bcl-2 expression were detected. Moreover, in vitro, T cells of asthmatic patients spontaneously released more interleukin-4 and exhibited more Bcl-2 expression than T cells from the control group. Arsenic trioxide treatment significantly decreased interleukin-4 release and down-regulated Bcl-2 expression in asthmatic patients, while it only slightly affected healthy controls. Dexamethasone treatment decreased interleukin-4 release in both groups examined. It did not significantly influence Bcl-2 expression. These results suggest that arsenic trioxide induces T cell apoptosis and decreases interleukin-4 release in T cells of asthmatic patients in vitro and that down-regulation of Bcl-2 expression may be an important mechanism.

Objective: To study the effects of arsenic trioxide on apoptosis of peripheral T-lymphocytes from asthmatic patients and normal subjects in vitro., Methods: The T-lymphocytes were isolated from the blood of 21 asthmatic patients and 20 healthy controls and treated with arsenic trioxide and dexamethasone. Cell apoptosis was observed by fluorescence microscope and measured with flow cytometry and Cytochrome C ELISA kit., Results: The T-lymphocytes from the asthmatic patients, when compared to those from of the healthy control, exhibited decelerated spontaneous apoptosis after a 24-hour incubation in vitro. Dexamethasone treatment significantly increased the percentage of apoptotic T-lymphocytes from both asthmatic patients and normal subjects in comparable magnitude. Arsenic trioxide treatment, in contrast, significantly increased the percentage of apoptotic T-lymphocytes from asthmatic patients, but slightly affected the cells from the control group., Conclusions: Spontaneous apoptosis of T-lymphocytes can be decelerated in asthmatic patients, whose T-lymphocytes are more sensitive to arsenic trioxide-induced apoptosis than those of normal subjects, but the T-lymphocytes from normal subjects and asthmatic patients are equally sensitive to dexamethasone.

The Ca(2+)-activated K+ channel was activated by a step increase in the intracellular Ca2+ concentration ([Ca2+]i) using the oil-gate concentration jump method in hippocampal neurons of rat. Limitations due to the unstirred volume between the excised inside-out membrane and the tip opening were examined.

ATP-dependent decay and recovery of the inward rectifier and ATP-sensitive K+ channels were investigated using inside-out patch recording in cardiac myocytes. The solution facing the inner side of the membrane was instantaneously changed with the oil-gate concentration jump method. Both channels were decayed by removing ATP and were recovered by reapplying ATP. The coexistence of Mg2+ was required for the recovery. 5'-Adenylylimidodiphosphate failed to reverse the ATP-dependent decay. The cumulative histograms of survival time and recovery time, obtained from the inward rectifier K+ channel, showed a single exponential distribution, time constants of which were 55 and 43 s, respectively. The time-dependent nature of decay and recovery was also confirmed in the ATP-sensitive K+ channel. The findings indicated that intracellular ATP is one of the factors that determines the activity of the K+ channels. It is most probable that phosphorylation of channel molecules is essential for maintaining the K+ channel in an operative state.

A new method was developed to instantaneously replace the solution on the inner side of an inside-out membrane patch in order to measure time courses with which active substances acted on single ionic channels. Inside-out membrane patches were isolated from single ventricular cells of the guinea pig heart. The recording bath consisted of two chambers separated by a partition having a narrow slit. Mixing of two test solutions through this slit was prevented by filling it with paraffin oil. The pipette tip with a tightly sealed inside-out membrane patch was moved through the oil from one solution to the other so that the pipette tip was instantaneously exposed to a new solution. When the pipette tip was jumped between different K+ concentrations, the leak current through the membrane patch increased or decreased with a half time of 6.3 +/- 3.0 ms (n = 15). The amplitude of single K+ channel currents changed to a new steady level within approximately 20 ms. These time courses were well explained by diffusion of K+ in the dead space between the pipette tip opening and the membrane patch. An application of this method to the ATP-regulated K+ channel revealed a latent period of 1-2 s before the channel started its activity after the instantaneous removal of ATP, whereas no obvious latency was observed in the rapid suppression of the channel, which was completed in 100-300 ms after reapplying ATP.

Kinetics for gating the ATP-sensitive K+ channel was studied by exposing the inside-out patch to instantaneous changes in the intracellular concentration of ATP ( [ATP]i) using the oil-gate concentration jump technique in guinea pig ventricular cells. The closing time course of the channel after increasing [ATP]i was exponential with a time constant (tau), which decreased with increasing [ATP]i. The linear 1/tau - [ATP]i relation revealed two different binding (closing) rate constants (mu) of 51.7 and 5.6 mM-1.s-1 and predicted a common unbinding (opening) rate constant (lambda) of 3.2 s-1. A variable latent period was observed before channel opening when [ATP]i was decreased. The mechanism of latency is not clear. Once the channel started to open at the change lowering [ATP]i, the opening time course was exponential. Measurements of the exponential tau obtained at 0 mM [ATP]i were divided into two groups with corresponding lambda of 2.8 and 20.1 s-1, respectively. The former agrees with the predicted value of 3.2 s-1, but in the latter case, tau for opening increased as [ATP]i was increased. This increase in tau was attributed to a decrease of lambda, which approached an asymptotic value of 3.2 s-1. We conclude that binding and unbinding of one molecule of ATP determine the gating of ATP-sensitive K+ channel. Different pairs of mu and lambda result in four types of gating patterns and practically two states of sensitivities to ATP.