DNA microarray has become an essential medical genetic diagnostic tool for its high-throughput, miniaturization and automation. The design and selection of oligonucleotide probes are critical for preparing gene chips with high quality. Several sets of probe design software have been developed and are available to perform this work now. Every set of the software aims to different target sequences and shows different advantages and limitations. In this article, the research and development of these sets of software are reviewed in line with three main criteria, including specificity, sensitivity and melting temperature (Tm). In addition, based on the experimental results from literatures, these sets of software are classified according to their applications. This review will be helpful for users to choose an appropriate probe-design software. It will also reduce the costs of microarrays, improve the application efficiency of microarrays, and promote both the research and development (R&D) and commercialization of high-performance probe design software.
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.
Confocal laser endomicroscopy technology can obtain cell-level images in real time and in situ, which can assist doctors in real-time intraoperative diagnosis, but its non-invasiveness makes it difficult to relocate the optical biopsy site. The confocal probe localization algorithm can automatically calculate the coordinates of the probe tip, that is, the coordinates of the optical biopsy site. In this paper, a confocal probe localization algorithm based on region growing and endoscope size prior was proposed. The algorithm detected the probe region by region growing on the probe edge image, then searched for tip points based on a given probe axis, and iteratively optimized it. Finally, based on the single-degree-of-freedom motion characteristics of the probe, the three-dimensional coordinates of the tip of the probe were calculated by using the prior information of the size of the endoscope, which solved the scale uncertainty problem of the monocular camera. The confocal probe localization algorithm was tested on the dataset collected in this paper. The results showed that our algorithm no longer relied on the color information of the probe, avoided the influence of uneven illumination on the gray value of the probe pixels, and had a more robust location accuracy and running speed. Within the length of the probe extending out of the endoscope from 0 to 5 cm, the pixel error could be as low as 11.76 pixels, and the average relative position error could be as low as 1.66 mm, which can achieve the real-time and accurate localization of the confocal probe.
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.
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.
Objective To investigate the accuracy of positioning perforator of medial sural artery with three-dimensional ultrasound technique guided by a wide band linear matrix array volume transducer probe before operation, and the effectiveness of the flap design based on this in repairing the dorsal foot wounds. Methods Between January 2019 and December 2022, 30 patients with skin and soft tissue defects of the dorsal foot were treated. There were 19 males and 11 females, with an average age of 43.9 years (range, 22-63 years). There were 12 cases of traffic accident injury, 15 cases of heavy crushing injury, and 3 cases of machine injury. The time from injury to hospitalization was 1-8 hours (mean, 3.5 hours). The wounds in size of 5 cm×3 cm to 17 cm×5 cm were thorough debrided and covered with vacuum sealing drainage dressing. Then the wounds were repaired with the medial sural artery perforator flaps after no obvious infection observed. To obtain the complete three-dimensional image, the number and position of the medial sural artery perforator branches and the position of the main blood vessels in the muscle were detected and recorded by wide band linear matrix array volume transducer probe before operation. Suitable perforating branches were selected to design the flap and guide the flap incision on this basis. The size of the perforating flap ranged from 6 cm×4 cm to 18 cm×6 cm. The sensitivity and positive predictive value were calculated by comparing preoperative exploration with intraoperative observation of perforating branches, so as to evaluate the positioning accuracy of three-dimensional ultrasound technique. The donor sites were sutured directly in 25 cases and repaired with free skin grafting in 5 cases. Results The 60 perforating branches of medial sural artery were found before operation and 58 during operation in 30 patients. Among them, pre- and intra-operative perforations were consistent with 56. The sensitivity was 93.3% and positive predictive value was 96.6%. The intramuscular position and route of the main blood vessels were basically consistent with the pre- and intra-operative observation. All flaps survived and wounds healed by first intention. All incisions at the donor sites healed by first intention, and all skin grafts survived. All patients were follow up 9-24 months (mean, 14.7 months). The appearance, color, and texture of the flaps were good, and no obvious effect on wearing shoes and walking. At last follow-up, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hind score ranged from 80 to 92, with an average of 87.5. The patient satisfaction was excellent in 29 cases and good in 1 case. Conclusion The three-dimensional ultrasound technique guided by the wide band linear matrix array volume transducer probe can accurately locate the perforating branch of the medial sural artery, and the three-dimensional imaging is more intuitive, which can be used to guide the design and incision of the medial sural artery perforator flap.
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.
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.
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.