Determination of Acetylcholinesterase Activity Based on Ratiometric Fluorescence Signal Sensing.

Acetylcholinesterase (AChE) plays an important role in the treatment of human diseases, environmental security and global food supply. In this study, the simple fluorescent indicators and MnO2 nanosheets were developed and integrated to establish a ratiometric fluorescence sensing system for the detection of AChE activity. Two fluorescence signals could be recorded independently at the same excitation wavelength, which extended the detection range and enhanced the visibility of results. Fluorescence of F-PDA was quenched by MnO2 nanosheets on account of inner filtering effect. Meanwhile, the nonfluorescent OPD was catalytically oxidized to 2,3-diaminophenazine by MnO2 nanosheets. The acetylcholine (ATCh) was catalytically hydrolyzed by AChE to enzymatic thiocholine, which decomposed MnO2 to Mn2+, recovered the fluorescence of F-PDA and reduced the emission of ox-OPD. Utilizing the fluorescence intensity ratio F468/F558 as the signal readout, the ratiometric fluorescence method was established to detect AChE activity. Under the excitation wavelength of 410 nm, the ratio F460/F558 against the AChE concentration demonstrated two linear relationships in the range 0.05 -1.0 and 1.0-50 U·L- 1 with a limit of detection (LOD) of 0.073 U·L- 1. The method was applied to the detection of AChE activity and the analysis of the inhibitor Huperzine-A. Due to the advantages of high sensitivity and favorable selectivity, the method possesses an application prospect in the activity deteceion of AChE and the screening of inhibitors.

Detection of Tyrosinase Activity and Inhibitor Validation Based on N-GQDs Fluorescence Sensor.

Tyrosinase inhibitors have the ability to resist melanin formation and can be used for clinical and cosmetic, so it is becoming extremely crucial to search a rapid and effective method for detecting t the activity of tyrosinase. In this study, a sensing probe based on Nitrogen-doped graphene quantum dots (N-GQDs) were prepared with carbamide and citric acid. Tyrosinase can oxidize dopamine to dopamine quinone, which can quench the fluorescence of N-GQDs based on the principle of fluorescence resonance energy transfer (FRET) process, and then the detection of tyrosinase activity can be achieved. The result demonstrated that the fluorescence intensity of N-GQDs was a linear correlation with the activity of tyrosinase. Wide detection linear ranges between 0.05 and 5 U/mL and high selectivity. The detection range of tyrosinase was 0.05 to 5 U/mL and LOD of 0.005 U/mL. According to the above, the fluorescence method established in this work could be successfully used for the trace analysis of tyrosinase and it was verified that KA is an inhibitor of tyrosinase.

Synergistic antimicrobial effect of nisin-octanoic acid nanoemulsions against E. coli and S. aureus.

Food safety is a major public health concern all over the world. Therefore, the prevention of food contamination is becoming extremely crucial. In this study, an antimicrobial nanoemulsion composed of water-soluble nisin and fat-soluble octanoic acid was successfully prepared. The results showed that the average particle size and the polymer dispersity index of the nisin-octanoic acid (NOA) nanoemulsion were around 52.21 nm and 0.253, respectively. The NOA nanoemulsion required less amounts of nisin and octanoic acid to achieve the effective antimicrobial effect against Escherichia coli and Staphylococcus aureus. In addition, the growth curves of E. coli and S. aureus were determined. The OD600 of NOA nanoemulsion was significantly lower than free nisin after being incubated for 24 h (p < 0.001), indicating that the antimicrobial effect of NOA nanoemulsion was outstanding. Meanwhile, the synergistic antimicrobial property of NOA nanoemulsion against E. coli and S. aureus was significantly better than free nisin under nonacid conditions (p < 0.05). Overall, the results of this study may provide guidance for the further application of nisin in more forms.

Synergistic antimicrobial system based on nisin and α-hydroxy organic acids.

Synergistic antimicrobial is a promising way to overcome microbial contamination in food and drugs. In the study, the synergistic effect between nisin and α-hydroxy organic acids on E. coli and S. aureus was investigated. The experimental results showed that the combined antibacterial ability of nisin-citric acid system was the most prominent. The FCI index also indicated that the combination of nisin and citric acid had synergistic effects on E. coli. When nisin was combined with citric acid, the inhibition rates of E. coli and S. aureus were increased to 4.43 and 1.49 times, respectively. Nisin-citric acid complex system could effectively slow down the proliferation of S. aureus and E. coli at lower concentrations, and can quickly destroy the cell membrane after 4 h of action. Therefore, the combination of nisin and citric acid is expected to be a potential solution for food and drug preservation.

Preparation and Optimization of O/W Emulsions Stabilized by Triglycerol Monolaurate for Curcumin Encapsulation.

Curcumin is one of the most studied chemo-preventive agents, which may cause suppression, retardation, or inversion of carcinogenesis. But its application is currently limited because of its poor water-solubility and bioaccessibility. A curcumin O/W emulsion was prepared by high-pressure homogenization, using triglyceride monolaurate as an emulsifier and medium chain triglycerides (MCT) as the oil phase. The effects of emulsifiers, emulsifier concentration, oil type, oil-to-water ratio, and homogenization pressure and processing cycles on the physical stability and droplet size distribution of curcumin-encapsulated O/W emulsions were evaluated in this study. The results showed that the mean droplet size of the O/W emulsions remained remarkably stable during 60 days of storage under both light and dark conditions. Curcumin retentions in O/W emulsions after 60 days of storage under light and dark conditions were 97.9% and 81.6%, respectively. In addition, during the simulated gastrointestinal digestion process, the mean droplet size of the O/W emulsions increased from 260 nm to 2743 nm after incubation with simulated gastric fluid (SGF) for 24 h, while the mean droplet size remained unchanged after incubation with simulated intestinal fluid (SIF). The results displayed negligible changes in curcumin content during incubation with simulated gastrointestinal fluids, indicating that effective protection of curcumin was achieved by encapsulation in the O/W emulsion. It is expected that curcumin will acquire high bioaccessibility and bioavailability when the O/W emulsion is to be used in clinical applications.

Treatment optimization of pelvic external beam radiation and/or vaginal brachytherapy for patients with stage I to II high-risk Endometrioid adenocarcinoma: a retrospective multi-institutional analysis.

BACKGROUND: For stage I to II high-risk endometrioid adenocarcinoma patients, the optimal adjuvant radiotherapy modality remains controversial. The present study sought to optimize the treatment of pelvic external beam radiation (EBRT) with/or vaginal brachytherapy (VBT) for high-risk endometrioid adenocarcinoma patients in multiple radiation oncology centers across China. METHODS: This article retrospectively reviewed stage I to II patients with resected endometrioid adenocarcinoma treated at 13 radiation centers from 1999 to 2015. Patients were eligible if they had high-risk features (stage IB Grade 3 disease or stage II Grade 1-3 disease) on the basis of ESMO-ESGO-ESTRO risk group consensus. RESULTS: A total of 218 patients were included. Fifty-one patients received EBRT, 25 patients received VBT, and 142 patients were administered EBRT combined with VBT. The three groups were comparable in baseline characteristics, except the proportion of stage IB and Grade 3 disease in the VBT group was significantly higher and their age was older. Survival analysis showed that OS, DFS, LRFS and DMFS were significantly different among the three groups. Two out of three groups were compared with each other, and results demonstrated that DFS, LRFS and DMFS were worse in the VBT group than in the EBRT or EBRT + VBT group. The 3-year OS rates were 95.2, 85.2 and 95.1% in the EBRT, VBT and EBRT + VBT groups, respectively (p = 0.043). There was no significant difference in survival outcomes between EBRT group and EBRT + VBT group. A propensity matching analysis was performed to eliminate group differences. The results demonstrated that DFS and LRFS were significantly improved in the pelvic radiation group compared to the VBT group. Distant failure accounted for most of the failure patterns. Patients in the VBT group had significantly increased local and regional recurrence rates than patients in the EBRT or EBRT + VBT group. Acute and chronic radiation-induced toxicities were well tolerated for all patients. CONCLUSION: For patients with postoperative stage I to II high-risk endometrioid adenocarcinoma, compared with VBT alone, radiotherapy modalities including EBRT significantly improved DFS, LRFS and DMFS with tolerable adverse effects. Overall survival was not significantly different between EBRT and EBRT + VBT modalities.

Magnetic nanoparticles immobilized thrombin ligand fishing to screen thrombin inhibitors in natural products.

In this study, thrombin was immobilized with magnetic particles modified by glutaraldehyde. The changes in secondary structures of immobilized enzyme revealed an increment in conformational rigidity and stability, which can be reflected in temperature and pH stability as well as the tolerance of organic reagents. The optimal reutilization times of magnetic particle immobilized thrombin were 7 times, and the half-life of enzyme activity preserved at room temperature was 5 days, which was 2.5 times higher than that of free enzyme. Ligusticum chuanxiong and Anemarrhenae Rhizoma with high enzyme inhibitory activity were selected for primary screening, and six potential inhibitors of thrombin were identified by HPLC/MS. The results showed that three compounds in Anemarrhenae Rhizoma had better predictive thrombin inhibitory activity. Through the in vitro thrombin activity inhibition experiment, it was also verified that mangiferin and neo-mangiferin had an ideal thrombin activity inhibition effect, which was consistent with the results of molecular docking.

Preoperative serum CA125 level and age at diagnosis: An effective prognosis prediction tool for patients with early-stage endometrial cancer.

OBJECTIVE: To investigate the combined predictive value of the preoperative serum cancer antigen 125 (CA125) level and age at diagnosis among patients with early-stage endometrial cancer (EC) after initial treatment. METHODS: We retrospectively analyzed data from patients with early-stage EC from 1999 to 2015 in multiple institutions in China. All 447 patients received postoperative adjuvant radiotherapy for FIGO 2009 stage I and II EC with complete data on preoperative serum CA125 levels. All patients were divided into four groups according to the ESMO-ESGO-ESTRO risk classification. The predictive probability of 5-year overall survival (OS) and the sensitivity and specificity of CA125 and age were calculated. RESULTS: The median follow-up time was 59 months (3-201 months). The 5-year OS and disease-free survival rates were 94.4% and 89.1%. Multivariate analysis showed that the preoperative CA125 level and age at diagnosis were independent prognostic factors for 5-year OS. The area under the curve for CA125 combined with age at diagnosis for 5-year OS was .692, and the corresponding sensitivity and specificity were 68.2% and 68.2% (p < .002), which were significantly better than the corresponding values for CA125 or age alone. After all 447 patients were divided into four groups according to CA125 combined with age, the 5-year OS of the elderly and higher CA125 group was only 73.7%. CONCLUSIONS: Although preoperative CA125 had limited sensitivity in predicting the prognosis for early-stage EC after initial treatment, it remains a useful serum marker for risk assessment of early-stage EC. Combining CA125 with age may increase its predictive sensitivity.

Utilization Trend and Comparison of Different Radiotherapy Modes for Patients with Early-Stage High-Intermediate-Risk Endometrial Cancer: A Real-World, Multi-Institutional Study.

This study aimed to compare the outcomes of RT modalities among patients who met different HIR criteria based on multicentric real-world data over 15 years. The enrolled patients, who were diagnosed with FIGO I-II EC from 13 medical institutes and treated with hysterectomy and RT, were reclassified into HIR groups according to the criteria of GOG-249, PORTEC-2, and ESTRO-ESMO-ESGO, respectively. The trends in RT modes utilization were reviewed using the Man-Kendall test. The rate of VBT alone increased from zero in 2005 to 50% in 2015, which showed a significant upward trend (p < 0.05), while the rate of EBRT + VBT utilization declined from 87.5% to around 25% from 2005 to 2015 (p > 0.05). There were no significant differences in OS, DFS, LRFS, and DMFS between VBT alone and EBRT ± VBT in three HIR cohorts. Subgroup analyses in the GOG-249 HIR cohort showed that EBRT ± VBT had higher 5-year DFS, DMFS, and LRFS than VBT alone for patients without lymph node dissection (p < 0.05). Thus, VBT could be regarded as a standard adjuvant radiation modality for HIR patients. EBRT should be administrated to selected HIR patients who meet the GOG-249 criteria and did not undergo lymph node dissection.

Reversal of Radiotherapy Resistance of Ovarian Cancer Cell Strain CAOV3/R by Targeting lncRNA CRNDE.

Radiotherapy resistance is one of the key factors of poor prognosis of ovarian cancer clinical treatment. The search for key targets of ovarian cancer radiotherapy resistance has become a high priority. Long noncoding RNA plays an important role in tumor development. However, the key lncRNA in ovarian cancer radiotherapy resistance is not identified. Our finding that lncRNA CRNDE is highly expressed in the radiotherapy resistance cell line CAOV3/R drew our attention. Therefore, in this study, we targeted lncRNA CRNDE to analyze whether it is a key factor of radiotherapy resistance in ovarian cancer. Ultimately, we found that silencing lncRNA CRNDE could reverse CAOV3/R radiotherapy resistance, which would be a boon to clinical treatment.

LAPTM4B promotes the progression of nasopharyngeal cancer.

Lysosomal protein transmembrane 4 beta (LAPTM4B) is a protein that contains four transmembrane domains. The impact of LAPTM4B on the malignancy of nasopharyngeal carcinoma (NPC) remains unclear. In the present study, we aimed to investigate the role of LAPTM4B in NPC. NPC tissue samples were used to evaluate the expression of LAPTM4B and its relationship with patient prognosis. Furthermore, we inhibited the expression of LAPTM4B in NPC cell lines and examined the effects of LAPTM4B on NPC cell proliferation, migration, and invasion. We found that LAPTM4B protein was mainly localized in the cytoplasm and intracellular membranes of NPC cells. LAPTM4B protein was upregulated in NPC tissues and cell lines. High LAPTM4B expression was closely related to pathological subtypes and disease stages in NPC patients. NPC patients with high LAPTM4B expression had a worse prognosis. LAPTM4B knockdown inhibited the proliferation, migration, and invasion ability of NPC cells. LAPTM4B plays a cancer-promoting role in the progression of NPC and may be a potential target for NPC therapy.

Endu combined with concurrent chemotherapy and radiotherapy for stage IIB-IVA cervical squamous cell carcinoma patients.

BACKGROUND: In recent years, the incidence of cervical cancer has increased with increasing life pressures and changes in women's social roles, posing a serious threat to women's physical and mental health. AIM: To explore the clinical effect of Endo combined with concurrent radiotherapy and chemotherapy in the treatment of advanced cervical squamous cell carcinoma. METHODS: A total of 120 patients admitted to the oncology department of our hospital were selected as the research subjects. They were equally divided into the test group and the control group (60 patients each) with a random number table. The test group was treated with Endo combined with concurrent radiotherapy and chemotherapy, and the control group was treated with concurrent radiotherapy and chemotherapy. We compared the serum thymidine kinase 1 (TK1), human epididymis protein 4 (HE4), vascular endothelial growth factor (VEGF), and squamous cell carcinoma-associated antigen (SCC-Ag) levels, the clinical effects and survival before and after radiotherapy and chemotherapy, the quality score, and the 3-year follow-up outcomes between the two groups. RESULTS: After chemotherapy, the complete remission + partial remission rate was 85.00% in the test group and 68.33% in the control group; the difference was not statistically significant (P > 0.05). Before chemotherapy, the serum TK1, HE4, VEGF, and SCC-Ag levels of the two groups were not significantly different (P > 0.05). After chemotherapy, the levels of serum TK1 (1.27 ± 0.40 pmol/L), HE4 (81.4 ± 24.0 pmol/L), VEGF (235.1 ± 38.0 pg/mL), and SCC-Ag (1.76 ± 0.55 ng/mL) were lower than those in the control group [TK1 (1.58 ± 0.51 pmol/L), HE4 (98.0 ± 28.6) pmol/L, VEGF (284.2 ± 54.1 pg/mL), and SCC-Ag (2.34 ± 0.78 ng/mL)]. The difference was statistically significant (P < 0.05). Before chemotherapy, there were no significant differences in the physical, role, mood, cognition, social and symptom scale scores of the two groups (P > 0.05). After chemotherapy, the physical, role, mood, cognitive and social scores were higher in the test group than in the control group, and the difference was statistically significant (P < 0.05). The symptom scale scores of the test group were all lower than those of the control group, and the difference was statistically significant (P < 0.05). The 3-year progression-free survival (PFS) rate was 43.33% in the test group and 26.67% in the control group; the overall survival (OS) rate was 48.33% in the test group and 33.33% in the control group; the differences were not statistically significant (P > 0.05). The 3-year PFS time of the test group was 20.0 mo, which was longer than that of the control group (15.0 mo), and the difference was significant (P < 0.05). The OS time of the test group was 30.0 mo, which was longer than that of the control group (18.0 mo), and the difference was significant (P < 0.05). CONCLUSION: Endo combined with concurrent radiotherapy and chemotherapy for the treatment of advanced cervical squamous cell carcinoma has a positive effect on reducing the level of tumor markers in patients, prolonging the PFS and OS times of patients, and improving the quality of life.

Effect of age as a continuous variable in early-stage endometrial carcinoma: a multi-institutional analysis in China.

OBJECTIVE: To explore the effect of age at diagnosis as a continuous variable on survival and treatment choice of patients with early-stage endometrial carcinoma (EC). MATERIALS AND METHODS: We retrospectively analyzed data from patients with early-stage EC from January 1999 to December 2015 in multiple institutions in China. All patients received primary hysterectomy/bilateral salpingo-oophorectomy and adjuvant radiotherapy for EC confirmed pathology of stage I and II disease (FIGO 2009 staging). All patients were divided into low-risk, intermediate-risk, high-intermediate-risk and high-risk groups according to ESMO-ESGO-ESTRO risk classification. RESULTS: The median follow-up time was 57months, and the 5-year cancer-specific survival (CSS) was 95.7%. Age as a continuous variable was an independent prognostic factor for CSS. With an increase in age, the hazard ratio (HR) for CSS increases gradually. Other independent prognostic factors included myometrial invasion (MI), grade, and chemotherapy. In the stratified analysis of age, the HRs of age on CSS in patients >70y were 5.516, 5.015, 4.469, 4.618, 5.334, and 5.821 after adjusting for cancer characteristics, local treatment, chemotherapy and treatment-related late toxicity. In patients 66-70-year-old, the HRs were 2.509, 2.074, 2.101, 2.091, 2.157 and 1.621 after adjusting for the above covariates. In patients ≤65y, there was no significant difference in the HR of age on CSS after adjustment. CONCLUSION: Age as a continuous variable is an independent prognostic factor and 65 year-old may be the best cut-off point for CSS in patients with early-stage EC in the Asian population. Quality of life should be given greater weight in the choice of therapeutic schedule for those patients >70 y.

The NS1 gene contributes to the virulence of H5N1 avian influenza viruses.

In the present study, we explored the genetic basis underlying the virulence and host range of two H5N1 influenza viruses in chickens. A/goose/Guangdong/1/96 (GS/GD/1/96) is a highly pathogenic virus for chickens, whereas A/goose/Guangdong/2/96 (GS/GD/2/96) is unable to replicate in chickens. These two H5N1 viruses differ in sequence by only five amino acids mapping to the PA, NP, M1, and NS1 genes. We used reverse genetics to create four single-gene recombinants that contained one of the sequence-differing genes from nonpathogenic GS/GD/2/96 and the remaining seven gene segments from highly pathogenic GS/GD/1/96. We determined that the NS1 gene of GS/GD/2/96 inhibited the replication of GS/GD/1/96 in chickens, while the substitution of the PA, NP, or M gene did not change the highly pathogenic properties of GS/GD/1/96. Conversely, of the recombinant viruses generated in the GS/GD/2/96 background, only the virus containing the NS1 gene of GS/GD/1/96 was able to replicate and cause disease and death in chickens. The single-amino-acid difference in the sequence of these two NS1 genes resides at position 149. We demonstrate that a recombinant virus expressing the GS/GD/1/96 NS1 protein with Ala149 is able to antagonize the induction of interferon protein levels in chicken embryo fibroblasts (CEFs), but a recombinant virus carrying a Val149 substitution is not capable of the same effect. These results indicate that the NS1 gene is critical for the pathogenicity of avian influenza virus in chickens and that the amino acid residue Ala149 correlates with the ability of these viruses to antagonize interferon induction in CEFs.