ObjectiveTo design a method for observing pulmonary microcirculation in vivo in a native tissue environment, due to the high incidence of lung diseases and the advantages of animal experiments in vivo.MethodsTen BALB/c male mice were randomly divided into group A and group B, with five mice in each group. A self-made apparatus was used to control the movement towards local lung tissues in order to get a stabilized observation plane, and then a 5-minute video was shot with laser confocal scanning microscope. During the filming, the mice in group A were injected with fluorescein isothiocyanate-dextran via the tail vein, and the mice in group B were injected with green fluorescent protein-platelets (extracted from the blood of tie2-cre&rosa26-tomato-EGFP transgenic black C57 male mice). The data of group A was used to observe the lungs perfusion and the damage to tissue by this method, and the data of group B was used to observe the movement of platelets.ResultsImage of lung structure obtained by this method was clear and stable. Mean areas of alveolus in an instant and at the 30th, 60th, 120th, 180th, and 300th second were (1 603±181), (1 588±183), (1 528±363), (1 506±353), (1 437±369), (1 549±307) μm2, respectively, and there were no significant differences between each time point (P>0.05). The video was smooth, the rapid movement of platelets was recorded and the particles were clear and without tailing; after the observation, hematoxylin-eosin staining showed no obvious damage to the lung tissue.ConclusionThe method can be used for the observation and research of the lung microcirculatory system in the living state of the mouse, and provides a methodological basis for studies of other lung diseases in vivo.
Objective To monitor the importance of establishing lung cancer models for immunological treatment through in vivo imaging system (IVIS). Methods In this study, a new optical bioluminescence IVIS was used to confirm the tumour formation and luminescence in male BALB/c nude mice by injecting A549-luc cells. First, A549-luc cells which expressed luciferase stably were transferred into nude mice by tail vein injection in order to establish a stable and reliable model of lung cancer. Then, D-fluorescein potassium salt was intraperitoneally injected every other week. The tumor formation and growth were dynamically observed on day 7th, 14th and 21st by IVIS Spectrum and pathological exam with hematoxylin-eosin staining. Results Animal model of lung cancer was successfully established, and the development of lung cancer was effectively monitored by IVIS real-time fluorescence value which was consistent with pathological exam, and tumor volume was correlated with fluorescence intensity (r=0.7996, P<0.01). Conclusions IVIS has multiple benefits, including high sensitivity and specificity, simple operation, and no radiation. IVIS Spectrum can measure the fluorescence of tumor formed by injection of A549-luc cells in nude mice metastasis of lung cancer in a non-invasive, real-time and dynamic mode, which is worthy of promotion for using in clinical research.
Objective To investigate the in vivo degradable properties of new calcium phosphate cement (CPC) containing poly lactic-co-glycolic acid (PLGA) so as to lay a foundation for the future clinical application. Methods A novel CPC containing PLGA (CPC/PLGA) was prepared according to a ratio of 45% dicalcium phosphate anhydrous ∶ 45% partially crystallized calcium phosphates ∶ 10% PLGA. Thirty-two adult New Zealand rabbits (weighing 2.2-3.0 kg, male or female in half) were divided into the experimental group (n=17) and the control group (n=15). The bone defect models of the bilateral femoral condyles (4.5 mm in diameter and 1.5 cm in depth) were made by drilling hole. Defect at the right side was repaired with CPC/ PLGA in the experimental group and with CPC in the control group, while defect at the left side was not treated as blank control. The general condition of rabbits was observed after operation; the histological observation and bone histomorphometric analysis were performed at 2, 4, 8, 16, and 24 weeks; and scanning electronic microscope (SEM) observation was performed at 8 and 16 weeks after operation. Results All rabbits survived to the end of experiment. The histological observation showed: CPC/PLGA degraded gradually, and the new-born bone trabecula ingrew; bone trabeculae became rough and b; and CPC/PLGA almost biodegraded at 24 weeks in the experimental group. The CPC degradation was much slower in the control group than in the experimental group. The total bone tissue percentage was 44.9% ± 23.7% in the experimental group, and 25.7% ± 10.9% in the control group, showing significant difference between 2 groups (t=3.302, P=0.001); and the bone tissue percentage showed significant difference between 2 groups at 8, 16, and 24 weeks (P lt; 0.05). The results of SEM observation showed that the pore size was 100-300 μm at 8 weeks after operation, new-born bone trabecula grew into the pores and combined bly with residual cement in the experimental group. Conclusion Novel CPC/PLGA has good in vivo degradable properties, and it can be an ideal bone substitute in future clinical application.
ObjectiveTo explore effect and mechanism of the carcinoma associated fibroblasts (CAFs) of breast cancer on growth and metastasis of breast cancer induced in nude mice by inoculation of CAFs and breast cancer cells. MethodsBreast cancer cell line of MDA-MB-231 (abbreviated as MDA), CAFs, and normal breast tissue fibroblasts (NFs) of the same breast cancer patient were collected, and mixed with normal saline (NS) or SDF-1 ligand blockers of four nitrogen heterocyclic fourteen alka (AMD3100, abbreviated as AMD) for inoculation of nude mice in vivo. According to the different combination, 36 nude mice were randomly divided into 6 groups:MDA+NS group, NFs+NS group, MDA+NFs+NS group, MDA+NFs+AMD group, MDA+CAFs+AMD group, and MDA+CAFs+NS group. Forty six days after the inoculation and feeding, volume of tumor, metastasis of lymph node, lung or liver were observed. In addition, level of plasma SDF-1 was tested by using ELISA method, and expressions of SDF-1 mRNA and protein in tumor specimens were detected by using real-time PCR and Western blot method respectively. ResultsExcept for NFs+ NS group, implanted tumor could be seen in nude mice of other 5 groups. In MDA+CAFs+NS group, the volume of tumor[(9.092±2.662) cm3], level of plasma SDF-1[(75.25±16.23) ng/L], and expression levels of SDF-1 mRNA (the median level was 14.714) and protein (the median level was 0.673). of tumor tissue were significantly greater or higher than those of the other 5 groups (P < 0.050). In addition, lymph node metastasis were found in 4 mice in MDA+CAFs+NS group, and 2 in MDA+NS group. The tumor metastasis of lung and liver was not found in all nude mice. ConclusionsCAFs can promote growth and lymph node metastasis of breast cancer, whose mechanism is related with SDF-1 secreted by CAFs and SDF-1/CXC chemokine receptor 4 (CXCR4), signal pathway.
Objective To evaluate the influence of PKH26 labeling on the biological function of the goat nucleus pulposus cells and the biological function of seeded cells in nude mice by in vivo imaging techonology. Methods Primary nucleus pulposus cells were isolated by enzymatic digestion from the nucleus pulposus tissue of the 1-year-old goat disc. The nucleus pulposus cells at passage 1 were labeled with PKH26 and the fluorescent intensity was observed under the fluorescence microscopy. The labeled cells were stained with toluidine blue and collagen type II immunocytochemistry. The cells viability and proliferation characteristics were assessed by trypan blue staining and MTT assay, respectively. Real-time fluorescent quantitative PCR was used to detect the gene expressions of collagen types I and II, and aggrecan. The fluorescent intensity and scope of the nucleus pulposus cells-scaffold composite in vivo for 6 weeks after implanting into 5 6-week-old male nude mice were measured by in vivo imaging technology. Results Primary nucleus pulposus cells were ovoid in cell shape, showing cluster growth, and the cells at passage 1 showed chondrocyte-like morphology under the inverted phase contrast microscope. The results of toluidine blue and collagen type II immunocytochemistry staining for nucleus pulposus cells at passage 1 were positive. The fluorescent intensity was even after labeling, and the cell viability was more than 95% before and after PKH26 labeling. There was no significant difference in cell growth curve between before and after labeling (P gt; 0.05). The real-time fluorescent quantitative PCR showed that there was no significant difference in gene expressions of collagen types I and II, and aggrecan between before and after labeling (P gt; 0.05). Strong fluorescence in nucleus pulposus cells-scaffold composite was detected and by in vivo imaging technology. Conclusion The PKH26 labeling has no effect on the activity, proliferation, and cell phenotype gene expression of the nucleus pulposus cells. A combination of PKH26 labeling and in vivo imaging technology can track the biological behavior of the cells in vivo.
This paper investigates the variation of lung tissue dielectric properties with tidal volume under in vivo conditions to provide reliable and valid a priori information for techniques such as microwave imaging. In this study, the dielectric properties of the lung tissue of 30 rabbits were measured in vivo using the open-end coaxial probe method in the frequency band of 100 MHz to 1 GHz, and 6 different sets of tidal volumes (30, 40, 50, 60, 70, 80 mL) were set up to study the trends of the dielectric properties, and the data at 2 specific frequency points (433 and 915 MHz) were analyzed statistically. It was found that the dielectric coefficient and conductivity of lung tissue tended to decrease with increasing tidal volume in the frequency range of 100 MHz to 1 GHz, and the differences in the dielectric properties of lung tissue for the 6 groups of tidal volumes at 2 specific frequency points were statistically significant. This paper showed that the dielectric properties of lung tissue tend to vary non-linearly with increasing tidal volume. Based on this, more accurate biological tissue parameters can be provided for bioelectromagnetic imaging techniques such as microwave imaging, which could provide a scientific basis and experimental data support for the improvement of diagnostic methods and equipment for lung diseases.
In vivo transplantation of tracheal grafts utilizes natural environment in vivo to improve cell adhesion, growth and scaffold properties, which can not only promote graft revascularization, but also induce immune tolerance and increase postoperative survival rate. Decellularized trachea with stem cells covering the outside layer and airway epithelial cells covering the inside layer can achieve complete mucosa re-epithelialization, cartilage cell growth and revascularization, using own body as a natural bioreactor to boost the maturity of tissue engineered trachea. Then transplantation at a normotopic in situ positioning is performed. This transplantation strategy provides a promising approach for the treatment of long-segment tracheal defects. This review focuses on the significance and research progress of constructing tissue engineered trachea in vivo.
ObjectiveTo investigate the changes in the nerve fiber layer of the cornea in patients with demyelinating optic neuritis (DON) and its correlation with visual acuity. MethodsA cross-sectional study. From March 2021 to July 2022, 27 cases (39 eyes) of DON patients diagnosed in the Department of Neurology and Ophthalmology of Beijing Tongren Hospital Affiliated to Capital Medical University were enrolled in this study. According to the serological test results, the patients were divided into aquaporin 4 antibody associated optic neuritis (AQP4-ON group) and myelin oligodendrocyte glycoprotein antibody associated optic neuritis (MOG-ON group), with 15 cases (19 eyes) and 12 cases (20 eyes) respectively. According to previous history of glucocorticoid treatment, the patients were divided into glucocorticoid treated group and non-glucocorticoid treated group, with 17 cases (27 eyes) and 10 cases (12 eyes) respectively. Twenty healthy volunteers (20 eyes) with age- and gender-matched were selected as the control group. All eyes underwent best corrected visual acuity (BCVA) and in vivo confocal microscopy (IVCM) examinations. BCVA was performed using Snellen's standard logarithmic visual acuity chart, which was converted into logarithmic minimum angle resolution (logMAR) visual acuity during statistics. The corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve fiber branch length (CNBL), corneal nerve fiber branch density (CNBD) and the density of corneal dendritic cells (DC) were detected by IVCM examination. Parameter comparison between groups by t-test and Kruskal-Wallis rank sum test. The correlation between logMAR BCVA and pamameters of corneal nerve fibers were analyzed using Spearman analysis. ResultsThe CNFL, CNFD, and CNBL of the DON group and the control group were (10.67±2.55) mm/mm2, (57.78±12.35) root/mm2, (3.27±1.34) mm/mm2, and (13.74±3.05) mm/mm2, (70.95±13.14) root/mm2, and (4.22±1.03) mm/mm2, respectively; the difference in CNFL, CNFD, and CNBL between the two groups were statistically significant (t=4.089, 3.795, 2.773; P＜0.05). The CNFL, CNBL, and CNBD of the affected eyes in the MOG-ON group and AQP4-ON group were (12.02±2.13) mm/mm2, (3.80±1.19) mm/mm2, (47.97±8.86) fibers/mm2, and (9.25±2.19) mm/mm2, (2.72±1.19) mm/mm2, (39.43±13.86) fibers/mm2, respectively; the differences in CNFL, CNBL, and CNBD between the two groups were statistically significant (t=－4.002, －2.706, －2.306; P＜0.05). The corneal DC density of the patients in the hormone treated group and the non-hormone treated group was (24.43±8.32) and (41.22±9.86) cells/mm2, respectively. The difference in corneal DC density between the two subgroups was statistically significant (P＜0.001). Correlation analysis showed that there was a significant negative correlation between logMAR BCVA and CNBL and CNFL in patients with DON (r=－0.422, －0.456; P＜0.05). ConclusionsThere are different degrees of corneal nerve fiber damage in patients with different types of DON. There was a negative correlation between BCVA and the length of corneal nerve fibers.
ObjectiveTo review the research progress of in vivo bioreactor (IVB) for bone tissue engineering in order to provide reference for its future research direction.MethodsThe literature related to IVB used in bone tissue engineering in recent years was reviewed, and the principles of IVB construction, tissue types, sites, and methods of IVB construction, as well as the advantages of IVB used in bone tissue engineering were summarized.ResultsIVB takes advantage of the body’s ability to regenerate itself, using the body as a bioreactor to regenerate new tissues or organs at injured sites or at ectopic sites that can support the regeneration of new tissues. IVB can be constructed by tissue flap (subcutaneous pocket, muscle flap/pocket, fascia flap, periosteum flap, omentum flap/abdominal cavity) and axial vascular pedicle (axial vascular bundle, arteriovenous loop) alone or jointly. IVB is used to prefabricate vascularized tissue engineered bone that matched the shape and size of the defect. The prefabricated vascularized tissue engineered bone can be used as bone graft, pedicled bone flap, or free bone flap to repair bone defect. IVB solves the problem of insufficient vascularization in traditional bone tissue engineering to a certain extent.ConclusionIVB is a promising method for vascularized tissue engineered bone prefabrication and subsequent bone defect reconstruction, with unique advantages in the repair of large complex bone defects. However, the complexity of IVB construction and surgical complications hinder the clinical application of IVB. Researchers should aim to develop a simple, safe, and efficient IVB.
Objective To investigate the sensitivity of 5 kinds of chemotherapeutic drugs on human colorectal cancer in vivo. Methods Xenografts in nude mice were set up by tumor tissues from 9 patients with colorectal cancer and nude mice were divided into 6 groups randomly， receiving saline （control group）， 5-fluorouracil （5-FU group）， doxorubicin（ADM group）， mitomycin （MMC group）， oxaliplatin （LOHP group）， and irinotecan （CPT-11 group）， respectively. The inhibitive rates （IR） of xenografts in 5 groups for each patient were calculated. Results The lowest and highest IR of 5 groups were 23.6% and 54.9% in 5-FU group， 23.7% and 69.5% in LOPH group， 23.6% and 82.6% in CPT-11group， 24.1% and 48.1% in MMC group， 5.8% and 20.7% in ADM group， respectively. The IR exceeded 40.0% in 7 patients of LOHP group， 6 patients of CPT-11 group， 4 patients of 5-FU group， and 1 patient of MMC group， respec-tively. Of 9 patients， the IR exceeded 40.0% to 3 kinds of drugs in 3 patients， to 2 kinds of drugs in 4 patients， the IR didn’t exceed 30.0% to 4 kinds of drug （IR was 82.6% to CPT-11） in 1 patient， and the IR didn’t exceed 31.0% to all 5 kinds of drugs in 1 patient. There were statistical differences on the IR of 5 kinds of drugs （H=24.061 2， P=0.000 1）. IR of ADM group was statistical lower than 5-FU group， MMC group， LOHP group， and CPT-11 group （P＜0.05），but there were no statistical differences between 5-FU group， MMC group， LOHP group， and CPT-11 group （P＞0.05）. Conclusions The xenografts from same patient have different sensitivity to different chemotherapy drugs， and the same chemotherapy drug corresponds to different IR in different patients. The IR of LOHP and CPT-11 are the highest， following by 5-FU and MMC.