142 research outputs found
Adsorption Properties of Typical Lung Cancer Breath Gases on Ni-SWCNTs through Density Functional Theory
A lot of useful information is contained in the human breath gases, which makes it an effective way to diagnose diseases by detecting the typical breath gases. This work investigated the adsorption of typical lung cancer breath gases: benzene, styrene, isoprene, and 1-hexene onto the surface of intrinsic and Ni-doped single wall carbon nanotubes through density functional theory. Calculation results show that the typical lung cancer breath gases adsorb on intrinsic single wall carbon nanotubes surface by weak physisorption. Besides, the density of states changes little before and after typical lung cancer breath gases adsorption. Compared with single wall carbon nanotubes adsorption, single Ni atom doping significantly improves its adsorption properties to typical lung cancer breath gases by decreasing adsorption distance and increasing adsorption energy and charge transfer. The density of states presents different degrees of variation during the typical lung cancer breath gases adsorption, resulting in the specific change of conductivity of gas sensing material. Based on the different adsorption properties of Ni-SWCNTs to typical lung cancer breath gases, it provides an effective way to build a portable noninvasive portable device used to evaluate and diagnose lung cancer at early stage in time
Diagnostic Ultrasound Megahertz Signal Detection with Multi-bounce Laser Microphone
Diagnostic ultrasound is one of the most common imaging modalities in the medical imaging field. One critical component of this imaging technology is designing sensitive receivers for detecting megahertz ultrasound signals. Currently, piezoelectric transducers have been the most widely used detectors for ultrasound signal. However, newer imaging techniques, such as photoacoustic imaging, require broader detection bandwidth and more sensitive detectors in order to work with significantly weaker signal. Conventional piezoelectric transducers may be limited in their ability to detect the full frequency bandwidth with high sensitivity, due to restricted transducer size and material composition. Sensitive and broadband ultrasound signal detecting techniques are needed for the development of advanced ultrasound imaging.
The multi-bounce laser microphone utilizes optical methods to detect the displacement of a gold-covered thin film diaphragm caused by the ultrasound signal pressure waves. This sensitive all-optical sensing technique would provide new opportunities for advanced ultrasound imaging as it is expected to achieve a higher signal-to-noise ratio (SNR) in a broader spectrum when compared with conventional transducers. Each laser beam bounce interrogating on the diaphragm would take a different optical path-length that reflects the displacement and be involved in accumulation of the ultimate phase difference between the reference and signal beams for the detector to recognize. The system was previously developed for detecting acoustic signatures generated by explosives below 10 kHz. To demonstrate its feasibility in biomedical imaging, experimental design in this work has applied this technique to detect ultrasound signals ranging from 100kHz to 1MHz.
The results of the experiments conducted in this work prove that the multi-bounce laser microphone system is capable of detecting megahertz range ultrasound signal. As compared to the conventional fibre-optic hydrophone, the laser microphone system achieves a higher SNR as the number of bounces increases. In the test of detecting 500kHz ultrasound signal, the SNR provided by the fibre-optic hydrophone is 38dB while the one achieved by the13-bounce laser microphone is 54dB. This is a promising sensitivity enhancement with a number of potential applications for detecting signals of significantly lower power, that would otherwise be very difficult for conventional piezoelectric ultrasound transducers to detect
Enhanced buoyancy and propulsion in 3D printed swimming micro-robots based on a hydrophobic nano fibrillated cellulose aerogel and porous lead-free piezoelectric ceramics
This paper provides the first demonstration of additively manufactured swimming micro-robots which combine a hydrophobic nanofibrillated cellulose aerogel, to provide long-term buoyancy, with a low acoustic impedance porous piezoelectric ceramic for improved propulsion. The hydrophobic nanocellulose aerogel is shown to exhibit a high and stable contact angle that was maintained for extended periods of time, which facilitates long-term and stable buoyancy of the micro-robot. To quantify the benefits of introducing porosity into the active piezoelectric element, a new analysis model was developed to inform material design and maximize the acoustic propulsion force. Detailed characterisation and modelling of the swimming robots demonstrated that a swimming robot based on a lead-free porous Ba 0.85Ca 0.15Zr 0.1Ti 0.9O 3 (BCZT) ceramic exhibited a higher acoustic radiation propulsion force and a faster swimming speed compared to a robot fabricated using a dense ceramic element. These benefits were associated with the lower elastic modulus, density and acoustic impedance of the porous piezoelectric material. The lower dielectric constant, reduced device capacitance, and lower resonant frequency of the porous piezoelectric element also significantly reduced the driving current and power requirements of the robot. This work therefore provides new insights on the impact of hydrophobic and acoustically matched piezoelectric materials on the performance of swimming micro-robots, and successfully demonstrates the use of porosity to improve acoustic impedance matching of resonant piezoelectric devices, such as micro-robots and ultrasonic transducers.</p
Penicillium marneffei-Stimulated Dendritic Cells Enhance HIV-1 Trans-Infection and Promote Viral Infection by Activating Primary CD4+ T Cells
Penicillium marneffei (P. marneffei) is considered an indicator pathogen of AIDS, and the endemicity and clinical features of P. marneffei have been described. While, how the co-infection of P. marneffei exacerbate deterioration of the immune response remains poorly understood. Here we isolated P. marneffei from the cutaneous lesions of AIDS patients and analyzed its effects on HIV-1-dendritic cells (DCs) interaction. We demonstrated that the monocyte-derived dendritic cells (MDDCs) could be activated by both thermally dimorphic forms of P. marneffei for significantly promoting HIV-1 trans-infection of CD4+ T cells, while these activated MDDCs were refractory to HIV-1 infection. Mechanistically, P. marneffei-activated MDDCs endocytosed large amounts of HIV-1 and sequestrated the internalized viruses into tetrapasnin CD81+ compartments potentially for proteolysis escaping. The activated MDDCs increased expression of intercellular adhesion molecule 1 and facilitated the formation of DC-T-cell conjunctions, where much more viruses were recruited. Moreover, we found that P. marneffei-stimulated MDDCs efficiently activated resting CD4+ T cells and induced more susceptible targets for viral infection. Our findings demonstrate that DC function and its interaction with HIV-1 have been modulated by opportunistic pathogens such as P. marneffei for viral dissemination and infection amplification, highlighting the importance of understanding DC-HIV-1 interaction for viral immunopathogenesis elucidation
Combined model of radiomics and clinical features for differentiating pneumonic-type mucinous adenocarcinoma from lobar pneumonia: An exploratory study
PurposeThe purpose of this study was to distinguish pneumonic-type mucinous adenocarcinoma (PTMA) from lobar pneumonia (LP) by pre-treatment CT radiological and clinical or radiological parameters.MethodsA total of 199 patients (patients diagnosed with LP = 138, patients diagnosed with PTMA = 61) were retrospectively evaluated and assigned to either the training cohort (n = 140) or the validation cohort (n = 59). Radiomics features were extracted from chest CT plain images. Multivariate logistic regression analysis was conducted to develop a radiomics model and a nomogram model, and their clinical utility was assessed. The performance of the constructed models was assessed with the receiver operating characteristic (ROC) curve and the area under the curve (AUC). The clinical application value of the models was comprehensively evaluated using decision curve analysis (DCA).ResultsThe radiomics signature, consisting of 14 selected radiomics features, showed excellent performance in distinguishing between PTMA and LP, with an AUC of 0.90 (95% CI, 0.83–0.96) in the training cohort and 0.88 (95% CI, 0.79–0.97) in the validation cohort. A nomogram model was developed based on the radiomics signature and clinical features. It had a powerful discriminative ability, with the highest AUC values of 0.94 (95% CI, 0.90–0.98) and 0.91 (95% CI, 0.84–0.99) in the training cohort and validation cohort, respectively, which were significantly superior to the clinical model alone. There were no significant differences in calibration curves from Hosmer–Lemeshow tests between training and validation cohorts (p = 0.183 and p = 0.218), which indicated the good performance of the nomogram model. DCA indicated that the nomogram model exhibited better performance than the clinical model.ConclusionsThe nomogram model based on radiomics signatures of CT images and clinical risk factors could help to differentiate PTMA from LP, which can provide appropriate therapy decision support for clinicians, especially in situations where differential diagnosis is difficult
Pan-cancer analysis reveals potential of FAM110A as a prognostic and immunological biomarker in human cancer
BackgroundDespite great success, immunotherapy still faces many challenges in practical applications. It was previously found that family with sequence similarity 110 member A (FAM110A) participate in the regulation of the cell cycle and plays an oncogenic role in pancreatic cancer. However, the prognostic value of FAM110A in pan-cancer and its involvement in immune response remain unclear.MethodsThe Human Protein Atlas (HPA) database was used to detect the expression of FAM110A in human normal tissues, the Tumor Immune Estimation Resource (TIMER) and TIMER 2.0 databases were used to explore the association of FAM110A expression with immune checkpoint genes and immune infiltration, and the Gene Set Cancer Analysis (GSCA) database was used to explore the correlation between FAM110A expression and copy number variations (CNV) and methylation. The LinkedOmics database was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Statistical analysis and visualization of data from the The Cancer Genome Atlas (TCGA) or the Genotype–Tissue Expression (GTEx) databases were performed using the R software (version 3.6.3). Clinical samples were validated using immunohistochemistry.ResultsFAM110A expression was elevated in most tumor tissues compared with that in normal tissues. CNV and methylation were associated with abnormal FAM110A mRNA expression in tumor tissues. FAM110A affected prognosis and was associated with the expression of multiple immune checkpoint genes and abundance of tumor-infiltrating immune cells across multiple types of cancer, especially in liver hepatocellular carcinoma (LIHC). FAM110A-related genes were involved in multiple immune-related processes in LIHC.ConclusionFAM110A participates in regulating the immune infiltration and affecting the prognosis of patients in multiple cancers, especially in LIHC. FAM110A may serve as a prognostic and immunological biomarker for human cancer
- …