Objective To increase the killing effect of aminolevulinic acid (ALA)-based photodynamic therapy (PDT) on a human skin squamous cell carcinoma cell line A431 by poly lactic-co-glycolic acid nanoparticles (PLGA NPs).Methods ALA-loaded PLGA NPs (ALA PLGA NPs) were prepared using a modified double emulsion solvent evaporation method,and characterized in terms of size,encapsulation efficiency,loading capacity and morphology.Transmission electron microscopy was carried out to observe the morphology of A431 cells after uptake of ALA PLGA NPs.To optimize incubation time,multi-mode microplate reader was used to describe the fluorescence kinetics of protoporphyrin Ⅸ generated by A431 cells during 24 hours of incubation with 0.1 mmol/L ALA,1 mmol/L ALA,2.7 g/L ALA PLGA NPs containing about 0.1 mmol/L ALA,and PLGA NPs without ALA separately.Some A431 cells were divided into 10 groups:control group receiving neither treatment nor irradiation,0.1 and 1 mmol/L ALA dark/PDT group incubated 0.1 and 1 mmol/L ALA respectively,ALA PLGA NP dark/PDT group incubated with ALA PLGA NPs of 2.7 g/L,PLGA NP dark/PDT group incubated with PLGA NPs of 2.7 g/L,simple irradiation group irradiated with a He-Ne laser (wavelength:635 nm,power density:8.6 mW/cm2,energy density:8 J/cm2) only.The dark groups were kept in darkness strictly by wrapping in aluminum foil,and PDT groups were irradiated using a He-Ne laser.After another 24 hours of culture following irradiation,methyl thiazolyl tetrazolium (MTF) assay was conducted to estimate the survival rate of cells.To study the effect of ALA PLGA NPs on cell apoptosis,some A431 cells were divided into three groups:control group receiving neither treatment nor irradiation,ALA-PDT group and ALA PLGA NP PDT group receiving PDT after incubation with ALA and ALA PLGA NPs respectively.Flow cytometry was performed to detect the apoptosis of A431 cells at 12 and 24 hours,separately,after the photodynamic therapy.Data were statistically analyzed using SPSS 13.0 software package by means of a t test.Results The prepared ALA PLGA NPs were spherical with a mean particle size of (65.6 ± 26) nm,encapsulation efficiency of (65.8 ± 7.2) ％,and drug loading capacity of (0.62 ± 0.27)％.ALA PLGA NPs could be uptaken by A431 cells and gathered in the cytoplasm.The PpIX fluorescence kinetic study showed that the fluorescence intensity increased with time within 24 hours in A431 cells incubated with ALA or ALA PLGA NPs.After 6 and 24 hours of incubation,the A431 cells incubated with 2.7 g/L ALA PLGA NPs showed a significant increase in the protoporphyrin Ⅸ fluorescence intensity compared with those incubated with 0.1 mmol/L ALA (both P ＜ 0.01).Further more,the survival rate of A431 cells was statistically lower in the ALA PLGA NP PDT group than in the 0.1 mmol/L ALA PDT group at 6 and 24 hours (t =35.685,5.262,respectively,both P ＜ 0.01).Elevated apoptosis rate was observed in the ALA PLGA NP PDT group compared with the ALA PDT group at 12 ((13.10 ± 0.50)％ vs.(4.90 ± 0.13)％,t =9.074,P＜ 0.01) and 24 ((30.17 ± 1.02)％ vs.(11.6 ± 0.59)％,t =9.095,P ＜ 0.01) hours.Conclusions ALA PLGA NPs can promote the formation of protoporphyrin Ⅸ,strengthen the killing effect of ALA-PDT on A431 cells in vitro,and enhance the apoptosis induced by ALA-PDT in tumor cells.

China ; Humans ; Neurology ; Pediatrics

OBJECTIVEMeasures of ventilation-CO₂output relationship have been shown to be more prognostic than peak O₂uptake in assessing life expectancy in patients with chronic heart failure (CHF). Because both the ratios (VE/Vco₂) and slopes (VE-vs-Vco₂) of ventilation-co₂ output of differing durations can be used, we aim to ascertain which measurements best predicted CHF life expectancy.

METHODSTwo hundred and seventy-one CHF patients with NYHA class II-IV underwent incremental cardiopulmonary exercise testing (CPET) and were followed-up for a median duration of 479 days. Four different linear regression VE-vs- Vco₂ slopes were calculated from warm-up exercise onset to: 180 s, anaerobic threshold (AT), ventilatory compensation point (VCP); and peak exercise. Five VE/Vco₂ ratios were calculated for the following durations: rest (120 s), warm-up (30 s), AT (60 s), lowest value (90 s), and peak exercise (30 s). Death or heart transplant were considered end-points. Multiple statistical analyses were performed.

RESULTSCHF patients had high lowest VE/Vco₂ (41.0 ± 9.2, 141 ± 30%pred), high VE/Vco₂ at AT (42.5 ± 10.4, 145 ± 35%pred), and high VE-vs-Vco₂ slope to VCP (37.6 ± 12.1, 126 ± 41%pred). The best predictor of death was a higher lowest VE/Vco₂ (≥ 42, ≥ 141%pred), whereas the VE-vs-Vco₂slope to VCP was less variable than other slopes. For death prognosis in 6 months, %pred values were superior: for longer times, absolute values were superior.

CONCLUSIONThe increased lowest VE/Vco₂ ratio easily identifiable and simply measured during exercise, is the best measurement to assess the ventilation-co₂output relationship in prognosticating death in CHF patients.

Carbon Dioxide ; metabolism ; Chronic Disease ; Disease Progression ; Exercise Test ; Heart Failure ; diagnosis ; mortality ; physiopathology ; Humans ; Life Expectancy ; Respiratory Function Tests

Purpose: Treatment-resistant cluster headache can be successfully alleviated with deep brain stimulation (DBS) of the posterior hypothalamus [1]. Magnetoencephalography (MEG) is a non-invasive functional imaging technique with both high temporal and high spatial resolution. However, it is not known whether the inherent electromagnetic (EM) noise produced by high frequency DBS is compatible with MEG. Materials and methods: We used MEG to record brain activity in an asymptomatic cluster headache patient with a DBS implanted in the right posterior hypothalamus while he made small movements during periods of no stimulation, 7 Hz stimulation and 180 Hz stimulation. Results: We were able to measure brain activity successfully both during low and high frequency stimulation. Analysis of the MEG recordings showed similar activation in motor areas in during the patient’s movements as expected. We also observed similar activations in cortical and subcortical areas that have previously been reported to be associated with pain when the patient’s stimulator was turned on or off [2,3]. Conclusion: These results show that MEG can be used to measure brain activity regardless of the presence of high frequency deep brain stimulation.

To improve overall satisfaction of patients with the hospital and build a harmonious doctor-patient relationship, a survey on satisfaction of patients with ECG examination was conducted in a tertiary A hospital. The analysis was carried out from the aspects of inspection environment, inspection process, inspection experience and overall satisfaction. Logistic regression model was used to analyze the effect of various variables on satisfaction. This paper found that the overall satisfaction rate of patients with ECG examination was 85.18%, lower than that of outpatients. Patients with different characteristics had different satisfaction degree with ECG examination. Patient satisfaction was lower on Mondays and Wednesdays than that on other inspection days, and was lower between 10 a.m. and 14 p.m. The longer the waiting time, the lower satisfaction degree of patients with examination. Based on the results, hospitals should improve the construction of humanistic soft environment to improve the medical environment, scientifically plan the medical treatment process of ECG examination, and further strengthen doctor-patient communication. The ECG room should further promote its management level and strengthen its cultural construction.