In this study, we explored the feasibility of biotin-mediated modified polymeric micelles for pancreatic cancer targeted photodynamic therapy. Poly (ethylene glycol)-distearoyl phosphatidyl ethanolamine (mPEG2000-DSPE) served as the drug-loaded material, biotin-poly(ethylene glycol)-distearoyl phosphatidyl ethanolamine (Biotin-PEG3400-DSPE) as the functional material and the polymeric micelles were prepared by a thin-film hydration method. The targeting capability of micelles was investigated by cell uptake assay in vitro and fluorescence imaging in vivo and the amounts of Biotin-PEG-DSPE were optimized accordingly. Hypocrellin B (HB), a novel photosensitizer was then encapsulated in biotinylated polymeric micelles and the anti-tumor efficacy was evaluated systemically in vitro and in vivo. The results showed that micelles with 5 mol % Biotin-PEG-DSPE demonstrated the best targeting capability than those with 20 mol % or 0.5 mol % of corresponding materials. This formulation has a small particle size [mean diameter of (36.74 ± 2.16) nm] with a homogeneous distribution and high encapsulation efficiency (80.06 ± 0.19) %. The following pharmacodynamics assays showed that the biotinylated micelles significantly enhanced the cytotoxicity of HB against tumor cells in vitro and inhibited tumor growth in vivo, suggesting a promising potential of this formulation for treatment of pancreatic cancer, especially those poorly permeable, or insensitive to radiotherapy and chemotherapy.

Objective To evaluate the effects of different blood-saving strategies on postoperative cellular immune function in patients undergoing resection for liver cancers.Methods Sixty-six ASA physical status Ⅰ or Ⅱ patients,aged 25-64 yr,with hepatocellular carcinoma classification G1-G3 and clinicopathological staging Ⅰ-Ⅳ,undergoing elective resection for liver cancers,were randomly divided into 3 groups (n =22 each) using a random number table:low central venous pressure group (L group),acutenormovolemic hemodilution group (A group),and acute normovolemic hemodilution combined with low central venous pressure group (AL group).Acute normovolemic hemodilution was performed after endotracheal intubation.Right jugular vein was cannulated for central venous pressure monitoring.Blood withdrawn from the radial artery at a rate of 25-40 ml/min was simultaneously replaced by iv infusion of the equal volume of 130/0.4 hydroxyethyl starch at the same rate until the target Hct (30％) was achieved.In A and AL groups,central venous pressure was maintained at 3-5 cm H2O during the procedure of liver parenchyma transection.Peripheral venous blood samples were taken before operation (T1,baseline) and on postoperative days 1,3 and 5 (T2-4) to determine the percentage of regulatory T-lymphocytes (CD4 + CD25 +,CD25 + Foxp3+),effective T-lymphocytes (CD8 +,CD4 + CD25-) and natural killer (NK) cells by flow cytometry.Results Compared with the baseline value at T1,the percentage of CD4 + CD25 +and CD25 + Foxp3+ was significantly decreased,and the percentage of CD8 + and CD4 + CD25-was increased at T3,4,and the percentage of NK cells was decreased at T2 in A and AL groups,and the percentage of CD4 + CD25 +and CD25 + Foxp3+ was decreased,and the percentage of CD8 + and CD4 + CD25-was increased at T4,and the percentage of NK cells was decreased at T2,3 in group L (P ＜ 0.05).Compared with L group,the percentage of CD4 + CD25 + and CD25 + Foxp3+ was significantly decreased at T3,the percentage of CD8 + was increased at T3,4,and the percentage of NK cells was increased at T3 in AL group (P ＜ 0.05).Conclusion Acute normovolemic hemodilution combined with low central venous pressure provides slighter inhibitory effect on the immune function of T-lymphocytes and NK cells in patients undergoing resection for liver cancers than either alone.

Objective To verify the effectiveness of electrical impedance tomography (EIT) with multi-layer electrodes in gastric emptying measurement by simulation experiments using EIT with three-layer electrodes.Methods Firstly,EIT system with three-layer electrodes and gastric emptying measurement simulation equipment was designed and constructed to simulate gastric emptying process and obtain EIT reconstruction images.Secondly,the region where the electrical characteristic of gastric changes was selected as region of interest.Finally,the relative impedance change rate in region of interest for every image obtained from all three layers was consecutively recorded,then the gastric emptying curve was formed and gastric emptying time was calculated.Results There are obvious differences among the sharp of impedance change curves of interested region for three layers,and the gastric emptying time and process of each layer is also different from one another.It is suggested that the passing path and emptying manner of food in gastric emptying process reflected by EIT images varied from layer to layer.Therefore,the necessity and feasibility of using EIT with three-layer electrodes in gastric emptying measurement study is verified.Conclusions EIT with three-layer electrodes can provide more abundant information of gastric motility function associated with gastric emptying pathology and physiology state.It is likely to be a noninvasive,convenient and effective imaging method for the detection and evaluation research on gastric emptying and gastric motility.

Objective To compare the efficacy of combined intravenous-inhalational anesthesia with propofol-fentanyl-sevoflurane in children undergoing minor surgery under spontaneous breathing with nasopharyngeal airway-face mask versus laryngeal mask airway (LMA).Methods Seventy-two children,scheduled for elective high ligation of indirect inguinal hernia,were randomly divided into 2 groups (n =36 each):nasopharyngeal airway-face mask group (group M) and LMA group (group L).Propofol 1.0 mg/kg and fentanyl 2.0μg/kg were injected intravenously.The spontaneous breathing was kept.After lass of consciousness,a face mask was placed for inhalation of pure oxygen at 2 L/min and 3 ％ sevoflurane.When BIS value reached 50-60,a size 2 LMA was inserted in group L and a nasopharyngeal airway was placed via the left nasal cavity and the face mask was held tightly and connected to the anesthesia machine in group M.Anesthesia was maintained with inhalation of 2％-4％ sevoflurane.Fentanyl 1 μg/kg was injected intravenously 5 min before skin incision.The concentration of sevoflurane was adjusted to maintain BIS value at 40-60 during surgery.Mean arterial pressure,heart rate,partial pressure of end-tidal carbon dioxide and pulse oxygen saturation were recorded before induction,at 3 min during induction,immediately after successful insertion of the airway,at skin incision,3 min after skin incision,and immediately after removal of the airway.The airway insertion time,success rate of insertion at first attempt,emergence time,and adverse reactions were recorded.Results Compared with group L,mean arterial pressure and heart rate were significantly decreased during airway insertion or removal,nasopharyngeal airway insertion time was shortened and the success rate of nasopharyngeal airway insertion at first attempt (100％) was increased,and the agitation score and incidence of obstruction of the upper respiratory tract were decreased in group M (P ＜ 0.05).Conclusion Combined inravenous-inhalational anesthesia with propofol-fentanyl-sevoflurane is easy to establish the airway,can maintain spontaneous breathing,has little influence on circulatory function and reduce complications during recovery from anesthesia in children undergoing minor surgery under spontaneous breathing with nasopharyngeal airway-face mask,and the efficacy is better than that with LMA.

Objective: To determine quercetin and kaempferol in stamen neulumbinis by HPLC. Methods : Shim-pack CLC-ODS column was used. Mobile phase consisted of methanol-0.025% phosphate. UV detector wavelength was set at 370nm. Results : The chromatographic peaks of quercetin and kaempferol and other components were completely separated. The average recovery was 96.8% and RSD was 1.97%. Conclusion : The experiment provided new markers and a reliable method for the quality control of Stamen Neulumbinis.

Three dimensional electrical impedance tomography (3D-EIT) became an important branch of EIT recently. It is important to research imaging and image quality evaluation methods for single targets of different positions and multi-targets in 3D field. Using finite element subdivision method, 3D-EIT field was dispersed into cube unit in the present study for models with single target located in the center of field, middle of field, and near to the edge, respectively. For models with two targets and four targets near to the field edge, Tikhonov-Noser algorithm was adopted in image reconstruction. Imaging error function ER and structure similarity degree function SSIM were introduced to evaluate the reconstructed images. For the models with signal target, with the movement of the target from the center to the edge of the field, the value of ER increased and SSIM decreased, and reconstruction quality decreased. For the models with multi-targets near to the field edge, ER and SSIM increased and decreased respectively with the increase of target number, mage quality also decreased. Tikhonov-Noser algorithm is an effective 3D-EIT algorithm. ER and SSIM are adaptive for the characteristic of 3D-EIT images, and it can quantitatively evaluate the 3D-EIT imaging effect from the two perspective of imaging error and structure quality.
Algorithms ; Electric Impedance ; Image Processing, Computer-Assisted ; Imaging, Three-Dimensional ; Tomography

In this study, we explored the feasibility of biotin-mediated modified polymeric micelles for pancreatic cancer targeted photodynamic therapy. Poly (ethylene glycol)-distearoyl phosphatidyl ethanolamine (mPEG2000-DSPE) served as the drug-loaded material, biotin-poly(ethylene glycol)-distearoyl phosphatidyl ethanolamine (Biotin-PEG3400-DSPE) as the functional material and the polymeric micelles were prepared by a thin-film hydration method. The targeting capability of micelles was investigated by cell uptake assay in vitro and fluorescence imaging in vivo and the amounts of Biotin-PEG-DSPE were optimized accordingly. Hypocrellin B (HB), a novel photosensitizer was then encapsulated in biotinylated polymeric micelles and the anti-tumor efficacy was evaluated systemically in vitro and in vivo. The results showed that micelles with 5 mol % Biotin-PEG-DSPE demonstrated the best targeting capability than those with 20 mol % or 0.5 mol % of corresponding materials. This formulation has a small particle size [mean diameter of (36.74 ± 2.16) nm] with a homogeneous distribution and high encapsulation efficiency (80.06 ± 0.19) %. The following pharmacodynamics assays showed that the biotinylated micelles significantly enhanced the cytotoxicity of HB against tumor cells in vitro and inhibited tumor growth in vivo, suggesting a promising potential of this formulation for treatment of pancreatic cancer, especially those poorly permeable, or insensitive to radiotherapy and chemotherapy.
Animals ; Antineoplastic Agents ; chemistry ; Biotin ; Drug Carriers ; chemistry ; Drug Screening Assays, Antitumor ; Humans ; Micelles ; Pancreatic Neoplasms ; drug therapy ; Photochemotherapy

Objective To measure the lethal dosage values ( LD50 ) of i.v.asarone injection for mice and to establish a standard for abnormal toxicity test of asarone injection to potentially reduce the occurrence of adverse drug reaction.Methods To obtain the LD50 value, a weighted linear probit regression method ( Bliss method) is employed. The limit of abnormal toxicity test is determined according to Appendix XI C in its 2010 edition of the Chinese pharmacopoeia.Results It is found that the LD50 of intravenously asarone injection in mice ranges from 51.9 to 153.1 mg/kg.The abnormal toxicity test should be added as an additional item in the standard.Conclusions Based on analyses in this study, an appropriate limit of abnormal toxicity test is 15 mg/kg, which is also in line with current medical standard in China.

Objective Practical electrical impedance tomography (EIT) system with certain measurement resolution (MR) and signal-to-noise ratio (SNR) differs a lot from ideal simulation conditions in EIT methodology research. The aim of this paper was to study the impact of practical system with different MR and SNR on EIT. Methods Based on the ideal simulation boundary voltages of adjacent excitation and adjacent measurement pattern, practical systems whose MR were 0.1 mV and 0.01 mV, SNR ranged from 40-80 dB and no noises were simulated, simulation study for three imaging models A, B and C with different positions in the to-be imaged field under practical system conditions above was carried out using the combined Tikhonov-NOSER regularization algorithm, and error of reconstruction (ER) function and structure similarity (SSIM) function were adopted for quantitative evaluation of image effect. Results There are differences between images obtained under different MR and SNR for different image models. In order to obtain images for three models, SNR of system should be at least 40-50 dB when MR was 0.01 mV. For the goal to obtain high quality images of A, B and C, SNR should be 80, 70 and 60 dB respectively. When MR was 0.1 mV, SNR for obtaining images of A, B, C were 60, 50 and 40 dB. Moreover, the improvement of images with increasing SNR under MR of 0.1 mV was not as obvious as that of MR at 0.01 mV. Conclusions Blind pursuit of single high SNR is of no help to improve system performance and image reconstruction effect except increasing the difficulties in hardware design. The extremity SNR is 50-60 dB for system with MR of 0.01 mV and 60-70 dB for system with MR of 0.1 mV.

Objective To study the etiology,relevant factors and endoscopic characteristics of acute lower gastrointestinal tract hemorrhage.Methods A total of 938 patients receiving emergency colonoscopy for acute lower gastrointestinal tract hemorrhage were collected to study the etiological profiles.Different causes between young group and elderly group were also recorded.Results The total detectable rate of acute lower gastrointestinal tract hemorrhage in respect of causes was 96.16％ (902/938).The five leading causes were colorectal malignancy (41.26％),erosive colorectal polypus (12.37％),inflammatory bowel disease (9.59％),erosive and ulcer colitis (10.34％) and hemorrhoids (8.64％).Compared with youth and middle age patients,the incidence of colorectal malignancy (x2 =68.116,df =2,P =0.000) and colorectal polyps (x2 =9.101,df =2,P =0.011) were significantly increased in elderly patients,while incidence of inflammatory bowel disease (x2 =62.150,df=2,P =0.000) and erosive and ulcer colitis (x2 =20.292,df =2,P =0.000) were significantly decreased in those patients.Conclusions Emergency colonoscopy for diagnosis of acute lower gastrointestinal tract hemorrhage is an important measure.The major manifestation is bleeding resulting from colorectal malignancy,erosive colorectal polypus,inflammatory bowel disease,erosive and ulcer colitis and anal hemorrhoid.Age is associated with the cause of lower gastrointestinal tract bleeding induced by different kinds of lesions at the colorectum.