ObjectiveTo prepare platelet-derived growth factor receptor β (PDGFRβ)-targeted near-infrared molecular probe and evaluate its potential in optical molecular imaging of lung cancer.MethodsPDGFRβ-specific affibody Z-tri was recombinantly expressed in Escherichia coli (E. coli) and purified using affinity chromatography. In vitro cell-binding of Z-tri was analyzed by flow cytometry. Cellular distribution of Z-tri in tumor grafts was determined by protein-tracing. The molecular probe CF750-Z-tri was prepared by conjugating near-infrared fluorescent dye CF750 to Z-tri. The optical images of xenografts of lung cancer were obtained by using CF750-Z-tri combined with optical imaging system.ResultsPDGFRβ-specific affibody Z-tri was highly expressed in E. coli and purified to homogeneity. Z-tri could bind PDGFRβ-positive cells but not PDGFRβ-negative cells cultured in vitro. In the tumor xenografts of human lung cancer, intravenously injected Z-tri was predominantly distributed on cells overexpressing PDGFRβ. The near infrared fluorescent dye CF750 was efficiently conjugated to Z-tri. Optical images with high contrast of lung cancer xenografts were produced by using the near-infrared fluorescent probe CF750-Z-tri combined with optical imaging system.ConclusionThe near-infrared fluorescent probe CF750-Z-tri can be used for optical imaging of human lung cancer, which takes great potential in optical imaging-guided surgery of lung cancer.
Polymer micelles formed by self-assembly of amphiphilic polymers are widely used in drug delivery, gene delivery and biosensors, due to their special hydrophobic core/hydrophilic shell structure and nanoscale. However, the structural stability of polymer micelles can be affected strongly by environmental factors, such as temperature, pH, shear force in the blood and interaction with non-target cells, leading to degradations and drug leakage as drug carriers. Therefore, researches on the structural integrity and in vivo distribution of micelle-based carriers are very important for evaluating their therapeutic effect and clinical feasibility. At present, fluorescence resonance energy transfer (FRET) technology has been widely used in real-time monitoring of aggregation, dissociation and distribution of polymer micelles (in vitro and in vivo). In this review, the polymer micelles, characteristics of FRET technology, structure and properties of the FRET-polymer micelles are briefly introduced. Then, methods and mechanism for combinations of several commonly used fluorescent probes into polymer micelles structures, and progresses on the stability and distribution studies of FRET-polymer micelles (in vitro and in vivo) as drug carriers are reviewed, and current challenges of FRET technology and future directions are discussed.
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 this paper, the differences between air probe and filled probe for measuring high-frequency dielectric properties of biological tissues are investigated based on the equivalent circuit model to provide a reference for the methodology of high-frequency measurement of biological tissue dielectric properties. Two types of probes were used to measure different concentrations of NaCl solution in the frequency band of 100 MHz–2 GHz. The results showed that the accuracy and reliability of the calculated results of the air probe were lower than that of the filled probe, especially the dielectric coefficient of the measured material, and the higher the concentration of NaCl solution, the higher the error. By laminating the probe terminal, liquid intrusion could be prevented, to a certain extent, to improve the accuracy of measurement. However, as the frequency decreased, the influence of the film on the measurement increased and the measurement accuracy decreased. The results of the study show that the air probe, despite its simple dimensional design and easy calibration, differs from the conventional equivalent circuit model in actual measurements, and the model needs to be re-corrected for actual use. The filled probe matches the equivalent circuit model better, and therefore has better measurement accuracy and reliability.
Lung cancer management is complex and requires a multi-disciplinary approach to provide comprehensive care. Interventional pulmonology (IP) is an evolving field that utilizes minimally invasive modalities for the initial diagnosis and staging of suspected lung cancers. Endobronchial ultrasound guided sampling of mediastinal lymph nodes for staging and detection of driver mutations is instrumental for prognosis and treatment of early and later stage lung cancers. Advances in navigational bronchoscopy allow for histological sampling of suspicious peripheral lesions with minimal complication rates, as well as assisting with fiducial marker placements for stereotactic radiation therapy. Furthermore, IP can also offer palliation for inoperable cancers and those with late stage diseases. As the trend towards early lung cancer detection with low dose computed tomography is developing, it is paramount for the pulmonary physician with expertise in lung nodule management, minimally invasive sampling and staging to integrate into the paradigm of multi-specialty care.
In order to help a surgeon to determine a proper canal filing cutting path in a hip replacement operation conveniently, this paper presents a kind of probe with combined structure. Firstly, the doctor can use this kind of combined probe to choose canal filing cutting path. Then, the doctor can use computer to guide the surgeon to file femoral cavity along the selected canal filing cutting path. Through hip replacement corpse experiments, filing effects and used time of using combined probe group and separate control group were analyzed. The experiment results showed that the methods introduced in this paper could lower the difficulty of hip replacement operations, improve the implantation of hip stem prostheses further, and reduce the incidence of surgical complications.
Objective To evaluate the diagnosis value of radial probe endobronchial ultrasound guide sheath transbronchial lung biopsy (RP-EBUS-GS-TBLB) combination with rapid on-site evaluation (ROSE) in peripheral pulmonary lesions (PPLs). Methods One hundred and fifty-eight patients with PPLs identified by computed tomography in Nanjing Chest Hospital underwent RP-EBUS-GS-TBLB with or without ROSE randomly between February 2016 and August 2017. The sensitivity, the procedure time, the biopsy times, and the complications were evaluated in the two groups. Results The diagnostic yield was 85.7% (72/84) in ROSE group and 70.3% (52/74) in No-ROSE group. There was significant difference in diagnostic sensitivity between the two groups (P<0.05). The mean procedure time and number of biopsy in ROSE group were less than those in No-ROSE group (P<0.01). No severe procedure related complications such as pneumothorax and hemoptysis were observed. Conclusions ROSE can improve the diagnostic sensitivity, and shorten the procedure time. RP-EBUS-GS-TBLB combined with ROSE is a safe and effective technique for PPLs.
ObjectiveTo compare the function and action pathways of VEGFA, VEGFB and VEGFC in VEGF family of mouse eye.MethodsUsing the BXD mouse gene data in Genenetwork database as template to compare and study the similarities and differences of VEGFA, VEGFB and VEGFC molecular pathways or potential functions in the whole genome expression spectrum of BXD recombinant mouse inbred line population, with multiple analytical methods and statistical strategies were used, such as gene expression level, target genes comparison, top genes comparison associated to target genes, expression Quantitative Trait Loci (eQTL).ResultsMatrix comparison showed strong positive correlation between two probes of VEGFC (r=0.732, P＜0.01), weak correlation between VEGFA 1420909 and VEGFC 1440739, VEGFA 1451959 and VEGFC 1451803, VEGFC 1419417959 and VEGFC 1439766, VEGFC 1451803 and VEGFC 1439766 (P＜0.05); there was no correlation between VEGFA 1420909 and four other genes except VEGFC 1440739, VEGFA 1451959 and VEGFC 1440739, VEGFB 1451803 and VEGFA 1420909/VEGFC 1419417/VEGFC 1440739 (P ＞0.05). In the comparative analysis of the relevant Top50 genes of each VEGF gene, most of the genes in BXD mouse were not significantly correlated with VEGFA, VEGFB and VEGFC except for the weak association of individual related genes. The results of eQTL analysis showed that each probe of VEGF gene was located on different chromosomes.ConclusionsThe expression levels and positive and negative correlations of VEGFA, VEGFB and VEGFC were different in the VEGF family of mouse eye, suggesting that these genes may play their role through different pathways.
Platelets are rapidly activated by activators and produce a large number of platelet microparticles (PMPs) with high coagulation activity, resulting in coagulation dysfunction. However, the generation mechanism of PMPs is still not clear. Hopping probe ion conductance microscopy (HPICM) has special technical advantages in non-contact, real-time, high-resolution imaging of living cells under physiological conditions. Using HPICM, this study monitored the processes of platelet activation and generation of PMPs in real time in the presence of calcium ionophore A23187 and cytochalasin D (CD), respectively. The results proved that the intracellular calcium concentration and the cytoskeletal proteins played important roles in the platelet activation and the generation of PMPs. Compared with the low density spread shape platelets (LDSS), the high density bubble shape platelets (HDBS) were more sensitive to the calcium ionophore A23187 and cytochalasin D. This research has a guiding significance for the further study on the relationship between platelet activation and coagulation function using HPICM.
With the development of medical diagnosis and treatment technology, ultrasound examination has been widely used in clinical practice, but it also faces certain safety hazards. If the ultrasound probe is not effectively disinfected after use, it may be contaminated by pathogenic bacteria transmitted from blood, mucous membranes, genital or rectal secretions, thus becoming a carrier for the transmission of pathogenic bacteria among patients. In addition, the frequent use of ultrasound probe and coupling agent is also an important factor affecting the occurrence of hospital infections. Multiple studies at home and abroad have shown that incomplete cleaning and disinfection of medical ultrasound probe can lead to hospital infection incidents, thereby affecting patient safety and medical quality. Exploring effective disinfection methods and disinfection effects of ultrasound probe is of great significance for hospital infection prevention and control. Therefore, this article provides a review of research related to disinfection of medical ultrasound probe.