Optimal weighted combinatorial forecasting model of QT dispersion of ECGs in Chinese adults.

This study aims to provide a scientific basis for unifying the reference value standard of QT dispersion of ECGs in Chinese adults. Three predictive models including regression model, principal component model, and artificial neural network model are combined to establish the optimal weighted combination model. The optimal weighted combination model and single model are verified and compared. Optimal weighted combinatorial model can reduce predicting risk of single model and improve the predicting precision. The reference value of geographical distribution of Chinese adults' QT dispersion was precisely made by using kriging methods. When geographical factors of a particular area are obtained, the reference value of QT dispersion of Chinese adults in this area can be estimated by using optimal weighted combinatorial model and reference value of the QT dispersion of Chinese adults anywhere in China can be obtained by using geographical distribution figure as well.

A theoretical study on a method for estimating dynamic intrinsic positive end-expiratory pressure in invasive mechanical ventilation / 中华危重病急救医学

Objective:To explore a simple method for measuring the dynamic intrinsic positive end-expiratory pressure (PEEPi) during invasive mechanical ventilation.Methods:A 60-year-old male patient was admitted to the critical care medicine department of Dongying People's Hospital in September 2020. He underwent invasive mechanical ventilation treatment for respiratory failure due to head and chest trauma, and incomplete expiratory flow occurred during the treatment. The expiratory flow-time curve of this patient was served as the research object. The expiratory flow-time curve of the patient was observed, the start time of exhalation was taken as T 0, the time before the initiation of inspiratory action (inspiratory force) was taken as T 1, and the time when expiratory flow was reduced to zero by inspiratory drive (inspiratory force continued) was taken as T 2. Taking T 1 as the starting point, the follow-up tracing line was drawn according to the evolution trending of the natural expiratory curve before the T 1 point, until the expiratory flow reached to 0, which was called T 3 point. According to the time phase, the intrapulmonary pressure at the time just from expiratory to inspiratory (T 1 point) was called PEEPi 1. When the expiratory flow was reduced to 0 (T 2 point), the intrapulmonary pressure with the inhaling power being removed hypothetically was called PEEPi 2. And it was equal to positive end-expiratory pressure (PEEP) set in the ventilator at T 3 point. The area under the expiratory flow-time curve (expiratory volume) between T 0 and T 1 was called S 1. And it was S 2 between T 0 and T 2, S 3 between T 0 and T 3. After sedation, in the volume controlled ventilation mode, approximately one-third of the tidal volume was selected, and the static compliance of patient's respiratory system called "C" was measured using the inspiratory pause method. PEEPi 1 and PEEP 2 were calculated according to the formula "C =ΔV/ΔP". Here, ΔV was the change in alveolar volume during a certain period of time, and ΔP represented the change in intrapulmonary pressure during the same time period. This estimation method had obtained a National Invention Patent of China (ZL 2020 1 0391736.1). Results:① PEEPi 1: according to the formula "C =ΔV/ΔP", the expiratory volume span from T 1 to T 3 was "S 3-S 1", and the intrapulmonary pressure decreased span was "PEEPi 1-PEEP". So, C = (S 3-S 1)/(PEEPi 1-PEEP), PEEPi 1 = PEEP+(S 3-S 1)/C. ②PEEPi 2: the expiratory volume span from T 2 to T 3 was "S 3-S 2", and the intrapulmonary pressure decreased span was "PEEPi 2-PEEP". So, C = (S 3-S 2)/(PEEPi 2-PEEP), PEEPi 2 = PEEP+(S 3-S 2)/C. Conclusion:For patients with incomplete expiratory during invasive mechanical ventilation, the expiratory flow-time curve extension method can theoretically be used to estimate the dynamic PEEPi in real time.

Simultaneous Determination of 7 Effective Components in Yao Medicine Yueli Yaomi Spray by QAMS / 中国药房

OBJECTIVE：To establish QAMS method for simultaneou s determination of 7 effective components in Yao medicine Yueli yaomi spray ，such as α-cyperone，α-pinene，β-pinene，limonene，β-elemene，caryophyllene oxide and ligustilide ， so as to provide method reference for the quality control of the preparation. METHODS ：GC method was adopted. The determination was performed on DB- 1701P capillary column ，using nitrogen as carrier gas. The temperature of the hydrogen flame ion detector was 240 ℃. The temperature was programmed ，the inlet temperature was 240 ℃，the injection volume was 1 μL and the split ratio was 20 ∶ 1. Using limonene as internal reference ，the relative correction factors of other 6 components were calculated，the contents of them were calculated with relative correction factors ，and then compared with the results of internal standard method （using naphthalene as internal standard ）. RESULTS ：The mass concentration linear range of α-cyperone， α-pinene，β-pinene，limonene，β-elemene，caryophyllene oxide and ligustilide were 0.008 9-1.110 0，0.028 3-3.540 0，0.020 5- 2.560 0，0.023 0-2.880 0，0.016 3-2.035 0，0.013 1-1.640 0，0.008 3-1.040 0 mg/mL（all r＞0.999 0）；the limits of quantification were 0.005 6，0.013 1，0.011 4，0.018 6，0.010 8，0.008 9，0.004 5 mg/mL；the detection limits were 0.001 9，0.004 1，0.003 7， 0.006 2，0.003 5，0.002 9，0.001 5 mg/mL；RSDs for precision ，stability（24 h），and repeatability tests were all less than 2％ （n＝5 or n＝6）； the average recoveries were 98.48％ ， 014） 101.37％，97.96％，99.80％，102.79％，97.77％，102.14％， and RSDs were all lower than 2％（n＝9），respectively. The average relative correction factors of α-cyperone，α-pinene， β-pinene，β-elemene，caryophyllene oxide and ligustilide were 1.045 8，0.621 0，0.488 5，0.382 9，0.708 9，0.956 9 respectively，and the RSDs were all lower than 2％（n＝6）. There wa s no statistical significance in contents of 7 components between QAMS method and internal standard method （P＞0.05）. CONCLUSIONS ：The established QAMS method is simple ， accurate，stable and reproducible ，and can be used for simultaneous determination for 7 components in Yueli yaomi spray.

Multifunctional polymeric micelle-based chemo-immunotherapy with immune checkpoint blockade for efficient treatment of orthotopic and metastatic breast cancer

Immunotherapy has become a highly promising paradigm for cancer treatment. Herein, a chemo-immunotherapy was developed by encapsulating chemotherapeutic drug doxorubicin (DOX) and Toll-like receptor 7 agonist imiquimod (IMQ) in low molecular weight heparin (LMWH)-d--tocopheryl succinate (TOS) micelles (LT). In this process, LMWH and TOS were conjugated by ester bond and they were not only served as the hydrophilic and hydrophobic segments of the carrier, but also exhibited strong anti-metastasis effect. The direct killing of tumor cells mediated by DOX-loaded micelles (LT-DOX) generated tumor-associated antigens, initiating tumor-specific immune responses in combination with IMQ-loaded micelles (LT-IMQ). Furthermore, the blockade of immune checkpoint with programmed cell death ligand 1 (PD-L1) antibody further elevated the immune responses by up-regulating the maturation of DCs as well as the ratios of CD8 CTLs/T and CD4 T/T. Therefore, such a multifunctional strategy exhibited great potential for inhibiting the growth of orthotopic and metastatic breast cancer.

Testify patient's blood electrolyte concentration a tendency to approach that of replacement-fluid in continuous renal replacement therapy / 中华危重病急救医学

Objective To prove with mathematical formula that the patient's blood electrolyte concentration shows a tendency to approach that of replacement-fluid after continuous renal replacement therapy (CRRT).Methods Electrolyte concentration of plasma,replacement-fluid and returning fluid were compared,and they were labeled as Cblood,Cnom,and Creturn respectively.The Creturn was calculated,and the relationship among them was demonstrated with comparison by mathematical formula.At last,according to their relationship,plasma change towards to the replacement fluid was analyzed.Results It was showed that Cblood＜Creturn＜Cnom or Cblood＞Creturn＞ Cnom,and according the relationship,it was derive that the trend of change in Cblood after circulation for m unit time was Cblood1 ＞Cblood2 ＞Cblood3 ＞ … ＞Cbloodm ＞Cblood or Cblood1 ＜ Cblood2 ＜Cblood3 ＜ … ＜Cbloodm ＜Cnom.The plasma electrolyte concentration would close to that of replacement fluid infinitely with the continue of CRRT.Conclusions With mathematical model,it is proved that the replacement fluid electrolyte concentration is the final target of the plasma.We must make up the replacement fluid correctly.And this results provide the basis for CRRT treatment of electrolyte disorder.