Construction of "lock-key" biological living material based on double engineered bacteria and its application on intestinal retention in vivo / 生物工程学报

At present, the research of biological living materials mainly focuses on applications in vitro, such as using a single bacterial strain to produce biofilm and water plastics. However, due to the small volume of a single strain, it is easy to escape when used in vivo, resulting in poor retention. In order to solve this problem, this study used the surface display system (Neae) of Escherichia coli to display SpyTag and SpyCatcher on the surface of two strains, respectively, and constructed a double bacteria "lock-key" type biological living material production system. Through this force, the two strains are cross-linked in situ to form a grid-like aggregate, which can stay in the intestinal tract for a longer time. The in vitro experiment results showed that the two strains would deposit after mixing for several minutes. In addition, confocal imaging and microfluidic platform results further proved the adhesion effect of the dual bacteria system in the flow state. Finally, in order to verify the feasibility of the dual bacteria system in vivo, mice were orally administrated by bacteria A (p15A-Neae-SpyTag/sfGFP) and bacteria B (p15A-Neae-SpyCatcher/mCherry) for three consecutive days, and then intestinal tissues were collected for frozen section staining. The in vivo results showed that the two bacteria system could be more detained in the intestinal tract of mice compared with the non-combined strains, which laid a foundation for further application of biological living materials in vivo.

Gold nanorods-mediated efficient synergistic immunotherapy for detection and inhibition of postoperative tumor recurrence

Tumor recurrence after surgery is the main cause of treatment failure. However, the initial stage of recurrence is not easy to detect, and it is difficult to cure in the late stage. In order to improve the life quality of postoperative patients, an efficient synergistic immunotherapy was developed to achieve early diagnosis and treatment of post-surgical tumor recurrence, simultaneously. In this paper, two kinds of theranostic agents based on gold nanorods (AuNRs) platform were prepared. AuNRs and quantum dots (QDs) in one agent was used for the detection of carcinoembryonic antigen (CEA), using fluorescence resonance energy transfer (FRET) technology to indicate the occurrence of

Comments on: a phase 1/2a, dose-escalation, safety and preliminary efficacy study of oral therapeutic vaccine in subjects with cervical intraepithelial neoplasia 3 / 부인종양

No abstract available.

Antitumor effect of 131 I-labeled anti-VEGFR2 targeted nanoparticles in anaplastic thyroid carcinoma mouse models / 中华核医学与分子影像杂志

Objective To investigate the radioactivity distribution of 131 I-bovine serum albumin ( BSA )-mesoporous silica nanoparticles ( MSNs )-anti-vascular endothelial growth factor receptor 2 (VEGFR2) in anaplastic thyroid carcinoma (ATC) and to explore its antitumor efficacy in ATC-bearing nude mouse models. Methods 131 I-BSA-MSNs-anti-VEGFR2 and 131 I-BSA-MSNs were constructed. FRO tumor xenografts were established and the SPECT/CT images of tumor-bearing mice were acquired at differ-ent time points after intratumoral injection with 131 I-BSA-MSNs-anti-VEGFR2 ( targeting group) , 131 I-BSA-MSNs ( non-targeting group) , Na131 I ( Na131 I group) and saline ( control group) , respectively. The changes of body mass and tumor volume in each group were recorded. Two-sample t test and log-rank test were used to analyze the data. Results After incubation for 3 h, the fluorescence intensity in targeting group was higher than that in non-targeting group (345.26±16.35 vs 280.61±9.65;t=5.90, P<0.05). After injection for 1-3 weeks, the radioactivity detected by SPECT/CT in targeting group was obviously stronger than that in non-targeting group ( t values:7.060-12.780, all P<0.05) . At the end of the observation, the tumor vol-ume of Na131I group, control group, non-targeting group and targeting group increased to (278.3±19.3)％, (296.6±24.2)％, (198.7±13.2)％ and (103.7±6.2)％ of the original volume, respectively. The body mass of the first 2 groups decreased to (88.6±3.0)％ and (86.2±3.1)％ of the original body mass respec-tively, while that of the latter 2 groups increased to (102.1±3.1)％ and (116.2±3.4)％ of the original body mass respectively. Survival analysis showed that the median survival time in targeting group ( 38 d) was sig-nificantly longer than that in non-targeting group (34 d;χ2=8.05, P<0.05). Conclusion 131I-BSA-MSNs-anti-VEGFR2 can effectively inhibit the tumor growth of ATC and prolong the survival of tumor-bearing nude mice, which gives a good suggestion for the treatment and prognosis evaluation of ATC.

Preliminary study on transdermal characteristics and sunface anesthetic effects of lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome in animals / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To prepare a new dental topical anesthetics, lidocaine hydrochloride loaded trans-activator of transcription peptide conjugated nano-niosome (LID-TAT-N), and to evaluate its transdermal properties and topical anesthesia effects.</p><p><b>METHODS</b>LID-TAT-N was prepared using reverse-phase evaporation method, and lidocaine loaded conventional liposome (LID-CL) was prepared in the same manner as positive control. The diameter, ζ potential and encapsulation efficiency of LID-TAT-N and LID-CL were measured. The skin permeation of LID-TAT-N was examined, and compared with LID-CL and lidocaine injection (LID-IJ, as negative control), using a Franz diffusion cell mounted with depilated mouse skin in vitro for 12 hours. Each experiment was repeated six times. The anesthetic effect of the new topical anesthetic was investigated on the cornea of rabbits.</p><p><b>RESULTS</b>The mean diameter of LID-TAT-N was smaller than that of LID-CL [(152.7 ± 10.6) nm vs. (259.5 ± 15.5) nm, P < 0.01]. The 12 h cumulative permeation amount was significantly higher in LID-TAT-N group [(1 340.0 ± 97.5) µg · cm(-2)] than those of LID-CL and LID-IJ groups [(1 060.6 ± 80.2), (282.6 ± 65.1) µg · cm(-2), respectively, P < 0.05]. Rabbit corneal reflex results showed that LID-TAT-N had anesthetic effect and the duration of analgesia [(24.8 ± 2.8) min] was also longer than that of LID-IJ [(14.5 ± 2.3) min, P < 0.05].</p><p><b>CONCLUSIONS</b>LID-TAT-N had good transdermal ability, and the advanced skin penetration feature can improve its tropical anesthetic effect.</p>

Preparation of superparamagnetic paclitaxel nanoparticles from modified chitosan and their cytotoxicity against malignant brain glioma / 生物医学工程学杂志

We synthesized the superparamagnetic paclitaxel nanoparticles from modified chitosan tangling around Fe3O4 ferrofluid and taxol, and observed the nanoparticles with transmission electronic microscopy (TEM). Then we evaluated the paramagnetism of the particles by vibration specimen magnetometer (VSM) and tested their cytotoxicity with flow cytometry (FCM). The prepared nanoparticle solution was black without any floccule or sediment and appeared transparent after diluted. The nanoparticles were spherical and dispersed in water with mean diameter of 15 nm under TEM and showed superparamagnetic character. FCM test showed the nanoparticles had significant toxic effects against malignant astrocytoma U251 cell lines, equal to taxol alone. These results showed that the superparamagnetic nanoparticle not only enhanced the solubility of paclitaxel in water, but also was superparamagnetic and cytotoxic, which make suitable tools for magnetic targeting chemotherapy of brain gliomas.

X-ray Analysis of Multiple Primary Cancer of Upper Digestive Tract(A Report of 34 Cases ) / 实用放射学杂志

Objective To investigate the clinical X-ray features and diagnostic criteria of multiple primary cancer of upper digestive tract (MPCUDT) as well as its pathogenesis ,and to analyze the causes of X-ray missed or mistaken diagnosis and to put forward the corresponding way of solutions.Methods X-ray findings of MPCUDT proved pathologically were retrospectively analyzed.Results (1)This disease mostly occurred in males .Male/Female=3.25/1. 88% of the patients were older than 50 years ;(2)78.8% of the cases with multiple primary cancer of esophagus were mostly distributed in upper and middle section ,72.2% of the cases with esophagogastric multiple primary cancer were distributed in middle and lower section of esophagus or cardiac part ;(3)The X-ray features of multiple primary cancer were the same as that of single ones .The patients with early carcinoma accounted for 14.5% of all cases , advanced carcinoma 85.5% ;(4)The rate of missed diagnosis was as high as 32.3%.Conclusion X-ray imaging has great value for the diagnosis of MPCUDT.