Association of procalcitonin levels with the progression and prognosis of hospitalized patients with COVID-19.

Rationale: Coronavirus disease 2019 (COVID-19) was first announced in Wuhan, and has rapidly evolved into a pandemic. However, the risk factors associated with the severity and mortality of COVID-19 are yet to be described in detail. Methods: We retrospectively reviewed the information of 1525 cases from the Leishenshan Hospital in Wuhan. Univariate and multivariate Cox regression analyses were generated to explore the relationship between procalcitonin (PCT) level and the progression and prognosis of COVID-19. Univariate and multivariate logistic regression analyses were performed to explore the relationship between disease severity in hospitalized patients and their PCT levels. Survival curves and the cumulative hazard function for COVID-19 progression were conducted in the two groups. To further detect the relationship between the computed tomography score and survival days, curve-fitting analyses were performed. Results: Patients in the elevated PCT group had a higher incidence of severe and critical severity conditions (P < 0.001), death, and higher computed tomography (CT) scores. There was an association between elevated PCT levels and mortality in the univariate ((hazard ratio [1], 3.377; 95% confidence interval [2], 1.012-10.344; P = 0.033) and multivariate Cox regression analysis (HR, 4.933; 95% CI, 1.170-20.788; P = 0.030). Similarly, patients with elevated PCT were more likely to have critically severe disease conditions in the univariate (odds ratio [2], 7.247; 95% CI, 3.559-14.757; P < 0.001) and multivariate logistic regression analysis (OR, 10.679; 95% CI, 4.562-25.000; P < 0.001). Kaplan-Meier curves showed poorer prognosis for patients with elevated PCT (P = 0.024). The CT score 1 for patients with elevated PCT peaked at day 40 following the onset of symptoms then decreased gradually, while their total CT score was relatively stable. Conclusion: PCT level was shown as an independent risk factor of in-hospital mortality among COVID-19 patients. Compared with inpatients with normal PCT levels, inpatients with elevated PCT levels had a higher risk for overall mortality and critically severe disease. These findings may provide guidance for improving the prognosis of patients with critically severe COVID-19.

Ghost spintronic THz-emitter-array microscope.

Terahertz (THz) waves show great potential in nondestructive testing, biodetection and cancer imaging. Despite recent progress in THz wave near-field probes/apertures enabling raster scanning of an object's surface, an efficient, nonscanning, noninvasive, deep subdiffraction imaging technique remains challenging. Here, we demonstrate THz near-field microscopy using a reconfigurable spintronic THz emitter array (STEA) based on the computational ghost imaging principle. By illuminating an object with the reconfigurable STEA followed by computing the correlation, we can reconstruct an image of the object with deep subdiffraction resolution. By applying an external magnetic field, in-line polarization rotation of the THz wave is realized, making the fused image contrast polarization-free. Time-of-flight (TOF) measurements of coherent THz pulses further enable objects at different distances or depths to be resolved. The demonstrated ghost spintronic THz-emitter-array microscope (GHOSTEAM) is a radically novel imaging tool for THz near-field imaging, opening paradigm-shifting opportunities for nonintrusive label-free bioimaging in a broadband frequency range from 0.1 to 30 THz (namely, 3.3-1000 cm-1).

The effect of metastasis patterns on survival in male patients with different breast cancer subtypes: results from the Surveillance, Epidemiology, and End Results (SEER) database.

BACKGROUND: Metastasis sites and breast cancer subtypes are important for breast cancer patients. This study aimed to assess possible relationships between them and their influence on prognosis in male breast cancer (MBC) patients. METHODS: We collected data on 2,983 patients with MBC from the Surveillance, Epidemiology, and End Results database, including 250 patients with M1 stage disease. Information on metastatic patterns was provided for bone, brain, liver, and lung metastases. MBC was classified into four subtypes: Her2-/HR+, Her2+/HR+, Her2+/HR-, and triple negative (TN). Univariate and multivariate logistic regression analysis were used to analyze the association, and Cox regression analyses were used to analyze prognosis. RESULTS: The bone was the most common metastatic site and the brain was the least common metastatic site. Patients with the Her2-/HR+ subtype had the highest proportion of metastatic disease, and Her2+/HR- patients had the lowest proportion. Univariate and multivariate logistic regression analyses showed that there were significant differences in distant metastasis patterns in patients with different subtypes. Men with the Her2+/HR+ or Her2-/HR+ subtypes with bone metastasis had better cancer specific survival (CSS), and those with the TN subtype had the worst CSS in all metastatic patterns. CONCLUSIONS: MBC subtypes are associated with different metastasis patterns and can have different effects on prognosis. This study might provide insights into a better understanding of MBC.

Terahertz wave near-field compressive imaging with a spatial resolution of over λ/100.

We demonstrate terahertz (THz) wave near-field imaging with a spatial resolution of ∼4.5 µm using single-pixel compressive sensing enabled by femtosecond-laser (fs-laser) driven vanadium dioxide (VO2)-based spatial light modulator. By fs-laser patterning a 180 nm thick VO2 nanofilm with a digital micromirror device, we spatially encode the near-field THz evanescent waves. With single-pixel Hadamard detection of the evanescent waves, we reconstructed the THz wave near-field image of an object from a serial of encoded sequential measurements, yielding improved signal-to-noise ratio by one order of magnitude over a raster-scanning technique. Further, we demonstrate that the acquisition time was compressed by a factor of over four with 90% fidelity using a total variation minimization algorithm. The proposed THz wave near-field imaging technique inspires new and challenging applications such as cellular imaging.

Giant impact of self-photothermal on light-induced ultrafast insulator-to-metal transition in VO2 nanofilms at terahertz frequency.

Ultrafast detection and switching of light are key processes in high-speed optoelectronic devices. However, the performances of VO2-based optoelectronics are strongly degraded by photothermal. The mechanism of the latter is still unclear. Here, by using femtosecond-laser (fs-laser) driven kinetic terahertz wave absorption, we quantitatively separate slow photothermal response and ultrafast photodoping response (e.g. light-induced insulator-to-metal transition) from second- to picosecond-timescales, and discover the competing interplay between them. With self-photothermal (mainly determined by fs-laser pulse repetition rate and pump fluence), the ultrafast transition time was degraded by 190% from 50 ps to 95 ps, the ultrafast transition threshold was decreased to 82% from 11mJ/cm2 to 9mJ/cm2, while the amplitudes of the two photoresponse are competing. Percolation theory, along with the macroscopic conductivity response, is used to explain the competing interplay. Our findings are relevant for designing and optimizing VO2-based ultrafast optoelectronic devices.