Tuberculosis (TB) immunity is affected by complex immune regulation processes, which involve various immune cells, immune molecules, and cytokines. Here, we evaluated the expression of B12, CD272 and ...miR-16 in peripheral blood mononuclear cells (PBMC) of patients with active pulmonary tuberculosis. The results showed that monocytes expressing CD272 or B12 were down-regulated in patients with tuberculosis. The expression of B12 and CD272 in T cells and monocytes is related to tuberculosis. In TB patients, the up-regulation of miR-16 was negatively correlated with B12 mRNA expression, miR-16 was mainly expressed in CD14
+
monocytes, and CD272 mRNA was mainly expressed in CD19
+
B cells. It is worth noting that the overexpression of miR-16 inhibits the expression of CD272 and B12 in monocytes of TB patients. After BCG stimulation, miR-16 expression of CD14
+
monocytes was up-regulated and B12 mRNA and CD272 mRNA expressions were down-regulated in TB patients. Finally, we found that miR-16 may participate in the TB immunization process through targeted regulation of B12 expression. These studies indicate that the expression of B12, CD272 and miR-16 in PBMC may be related to tuberculosis.
The prevalence of drug-resistant
(Mtb) strains makes disease control more complicated, which is the main cause of death in tuberculosis (TB) patients. Early detection and timely standard treatment ...are the key to current prevention and control of drug-resistant TB. In recent years, despite the continuous advancement in drug-resistant TB diagnostic technology, the needs for clinical rapid and accurate diagnosis are still not fully met. With the development of sequencing technology, the research of human microecology has been intensified. This study aims to use 16 rRNA sequencing technology to detect and analyze upper respiratory flora of TB patients with anti-TB drug sensitivity (DS, n = 55), monoresistance isoniazide (MR-INH, n = 33), monoresistance rifampin (MR-RFP, n = 12), multidrug resistance (MDR, n = 26) and polyresistance (PR, n = 39) in southern China. Potential microbial diagnostic markers for different types of TB drug resistance are searched by screening differential flora, which provides certain guiding significance for drug resistance diagnosis and clinical drug use of TB. The results showed that the pulmonary microenvironment of TB patients was more susceptible to infection by external pathogens, and the infection of different drug-resistant Mtb leads to changes in different flora. Importantly, seven novel microorganisms (Leptotrichia, Granulicatella, Campylobacter, Delfitia, Kingella, Chlamydophila, Bordetella) were identified by 16S rRNA sequencing as diagnostic markers for different drug resistance types of TB. Leptotrichia, Granulicatella, Campylobacter were potential diagnostic marker for TB patients with INH single-resistance. Delftia was a potential diagnostic marker for TB patients with RFP single drug-resistance. Kingella and Chlamydophila can be used as diagnostic markers for TB patients with PR. Bordetella can be used as a potential diagnostic marker for identification of TB patients with MDR.
We present the scintillation velocity measurements of FRB~20201124A from the FAST observations, which reveal an annual variation. This annual variation is further supported by changes detected in the ...scintillation arc as observed from the secondary spectrum. We attribute the annual velocity variation to the presence of a moderately anisotropic scattering screen located at a distance of 0.4\(\pm\)0.1~kpc from Earth. Our results prove that the scintillation of this FRB is mainly caused by material close to Earth on a Galactic scale. However, scintillation observations of other FRBs may expose their surrounding environment or uncover possible orbital motion if scintillation is caused by materials in their host galaxy.
In regions with strongly varying electron density, radio emission can be magnified significantly by plasma lensing. In the presence of magnetic fields, magnification in time and frequency will be ...different for two circular polarizations. We show how these effects can be used to measure or constrain the magnetic field parallel to the line of sight, \(B_\parallel\), as well as its spatial structure, \(\sigma_{B_\parallel}\), in the lensing region. In addition, we discuss how generalized Faraday rotation can constrain the strength of the perpendicular field, \(B_\perp\). We attempt to make such measurements for the Black Widow pulsar, PSR~B1957+20, in which plasma lensing was recently discovered. For this system, pressure equilibrium suggests \(B\gtrsim 20\,\)G at the interface between the pulsar and companion winds, where the radio eclipse starts and ends, and where most lensing occurs. We find no evidence for large-scale magnetic fields, with, on average, \(B_\parallel=0.02\pm0.09\,\)G over the egress lensing region. From individual lensing events, we strongly constrain small scale magnetic structure to \(\sigma_B<10\,\)mG, thus excluding scenarios with a strong but rapidly varying field. Finally, from the lack of reduction of average circular polarization in the same region, we rule out a strong, quasi-transverse field. We cannot identify any plausible scenario in which a large magnetic field in this system is concealed, leaving the nature of the interface between the pulsar and companion winds an enigma. Our method can be applied to other sources showing plasma lensing, including other eclipsing pulsars and fast radio bursts, to study the local properties of the magnetic field.
Radio pulsars scintillate because their emission travels through the ionized interstellar medium via multiple paths, which interfere with each other. It has long been realized that the scattering ...screens responsible for the scintillation could be used as `interstellar lenses' to localize pulsar emission regions. Most scattering screens, however, only marginally resolve emission components, limiting results to statistical inferences and detections of small positional shifts. Since screens situated close to the source have better resolution, it should be easier to resolve emission regions of pulsars located in high density environments such as supernova remnants or binaries in which the pulsar's companion has an ionized outflow. Here, we report events of extreme plasma lensing in the `Black Widow' pulsar, PSR~B1957+20, near the phase in its 9.2 hour orbit in which its emission is eclipsed by its companion's outflow. During the lensing events, the flux is enhanced by factors of up to 70--80 at specific frequencies. The strongest events clearly resolve the emission regions: they affect the narrow main pulse and parts of the wider interpulse differently. We show that the events arise naturally from density fluctuations in the outer regions of the outflow, and infer a resolution of our lenses comparable to the pulsar's radius, about 10\,km. Furthermore, the distinct frequency structures imparted by the lensing are reminiscent of what is observed for the repeating fast radio burst FRB 121102, providing observational support for the idea that this source is observed through, and thus at times strongly magnified by, plasma lenses.
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