The potential mechanism of the progression from latent to active tuberculosis based on the intestinal microbiota alterations.

INTRODUCTION: Tuberculosis (TB) poses a serious challenge to global health systems. The altered intestinal microbiota is associated with the pathogenesis of TB, but the exact links remain unclear. METHODS: 16 S rDNA sequencing was performed to comprehensively detect the changes in the intestinal microbiota of feces from active TB (ATB), latent TB infection (LTBI) and healthy controls (HC). RESULTS: The rarefaction curves demonstrated the sequencing results' validity. The alpha diversity was lowest in ATB, while highest in HC. Boxplot of beta diversity showed significant differences in every two groups. LDA Effect Size (LEfSe) Analysis revealed differences in probiotic bacteria like Romboutsia, Bifidobacterium and Lactobacillus in LTBI, and pro-inflammatory bacteria like R. gnavus, Streptococcus and Erysipelatoclostridium in ATB, corresponding to the cluster analysis. PICRUST2 analysis revealed the pentose phosphate pathway was active in ATB and LTBI (more active in ATB). The differences between the groups are statistically significant at the P<0.05 level. CONCLUSION: Our study indicated that from LTBI to ATB, some intestinal microbiota inhibit the synthesis of interferon (INF)-γ and interleukin (IL)-17, promoting the survival and spread of Mycobacterium tuberculosis (M. tb). In addition, the metabolites secreted by intestinal microbiota and dysbiosis in intestine also have an effect on the development of LTBI to ATB.

Untargeted Metabolomics of Feces Reveals Diagnostic and Prognostic Biomarkers for Active Tuberculosis and Latent Tuberculosis Infection: Potential Application for Precise and Non-Invasive Identification.

Purpose: Distinguishing latent tuberculosis infection (LTBI) from active tuberculosis (ATB) is important to control the prevalence of tuberculosis; however, there is currently no effective method. The aim of this study was to discover specific metabolites through fecal untargeted metabolomics to discriminate ATB, individuals with LTBI, and healthy controls (HC) and to probe the metabolic perturbation associated with the progression of tuberculosis. Patients and Methods: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed to comprehensively detect compounds in fecal samples from HC, LTBI, and ATB patients. Differential metabolites between the two groups were screened, and their underlying biological functions were explored. Candidate metabolites were selected and enrolled in LASSO regression analysis to construct diagnostic signatures for discriminating between HC, LTBI, and ATB. A receiver operating characteristic (ROC) curve was applied to evaluate diagnostic value. A nomogram was constructed to predict the risk of progression of LTBI. Results: A total of 35 metabolites were found to exist differentially in HC, LTBI, and ATB, and eight biomarkers were selected. Three diagnostic signatures based on the eight biomarkers were constructed to distinguish between HC, LTBI, and ATB, demonstrating excellent discrimination performance in ROC analysis. A nomogram was successfully constructed to evaluate the risk of progression of LTBI to ATB. Moreover, 3,4-dimethylbenzoic acid has been shown to distinguish ATB patients with different responses to etiological tests. Conclusion: This study constructed diagnostic signatures based on fecal metabolic biomarkers that effectively discriminated HC, LTBI, and ATB, and established a predictive model to evaluate the risk of progression of LTBI to ATB. The results provide scientific evidence for establishing an accurate, sensitive, and noninvasive differential diagnosis scheme for tuberculosis.

Bias Controller of Mach-Zehnder Modulator for Electro-Optic Analog-to-Digital Converter.

As one of the core devices for an electro-optic analog-to-digital converter (ADC), the Mach-Zehnder (MZ) modulator plays an important role, and the output stability of the MZ modulator has a decisive influence on the conversion accuracy of the ADC. This paper proposed a pilot tone-based method to stabilize the bias point of the modulator. This method could obtain the corresponding control voltage of the MZ modulator by adding a KHz-level dither tone to the bias end of the modulator and calculating the ratio of the first and second harmonic components. The experimental results showed that the output optical power of the modulator was stable at 3.2 dB when the bias point of the modulator was set at the orthogonal point. Moreover, the fluctuation range was not more than 0.15 dB, the first harmonic of the output signal was stable at 50.5 dB, and the fluctuation range was not more than 0.6 dB. The proposed bias controller based on the field programmable gate array (FPGA) and digital signal processing (DSP) can stabilize the modulator bias point at the orthogonal point and with a relatively high locking accuracy.

A Self-Powered Engine Health Monitoring System Based on L-Shaped Wideband Piezoelectric Energy Harvester.

Engine health monitoring is very important to maintain the life of engines, and the power supply to sensor nodes is a key issue that needs to be solved. The piezoelectric vibration energy harvester has attracted much attention due to its obvious advantages in configuration, electromechanical conversion efficiency, and output power. However, the narrow bandwidth has restricted its practical application. A self-powered engine health monitoring system was proposed in this paper, and an L-shaped wideband piezoelectric energy harvester was designed and implemented. The L-shaped beam-mass structure and the piezoelectric bimorph cantilever beam structure was combined to form the wideband piezoelectric energy harvester configuration, which realized effective output at both resonance points. The theoretical model and finite element simulation analysis of the wideband piezoelectric energy harvester were proposed and the parameters were optimized based on that to meet the requirement of the vibration frequency of the engine. The experimental results show that the proposed energy harvester can be applied into the automobile engine health monitoring system. Engine signal analysis results also demonstrate that the proposed system can be used for engine health monitoring.

Hexaaqua-zinc(II) 4,4'-(1,2-dihy-droxy-ethane-1,2-di-yl)dibenzoate monohydrate.

The title compound, [Zn(H(2)O)(6)](C(16)H(12)O(6))·H(2)O, consists of one 4,4'-(1,2-dihy-droxy-ethane-1,2-di-yl)dibenzoate anion lying on an inversion centre, one [Zn(H(2)O)(6)](2+) dication lying on a mirror plane and one solvent water mol-ecule located on a mirror plane. The octahedral [Zn(H(2)O)(6)](2+) cations, solvent water mol-ecules and anions inter-act via O-H⋯O hydrogen bonds, forming a three-dimensional network.

[µ-1,3-Bis(3,5-dimethyl-1H-pyrazol-1-yl-κN)propan-2-olato-κO:O]bis-[(ethanol-κO)zinc(II)] bis-(perchlorate).

In the centrosymmetric dinuclear title complex, [Zn(2)(C(13)H(19)N(4)O)(2)(C(2)H(5)OH)(2)](ClO(4))(2), the Zn(II) atom is in a distorted trigonal-bipyramidal coordination geometry. The equatorial plane is constructed by one N atom and one O atom from two 1,3-bis-(3,5-dimethyl-pyrazol-1-yl)propan-2-olate (bppo) ligands and one O atom from an ethanol mol-ecule. One N atom and one O atom from the two bppo ligands occupy the axial positions. Inter-molecular O-H⋯O hydrogen bonds between the ethanol mol-ecules and perchlorate anions, and O⋯π inter-actions between the perchlorate anions and pyrazole rings [O⋯centroid distances = 3.494 (3) and 3.413 (3) Å], lead to a chain structure along [010].

catena-Poly[[diaqua-dichlorido-manganese(II)]-µ-1,1'-bis-(1H-1,2,4-triazol-1-ylmeth-yl)ferrocene].

In the title complex, [FeMn(C(8)H(8)N(3))(2)Cl(2)(H(2)O)(2)](n), the Mn(II) atom, located on an inversion center, is octa-hedrally coordinated by two N atoms from two adjacent 1,1'-bis-(1H-1,2,4-triazol-1-ylmeth-yl)ferrocene (btmf) ligands and two Cl atoms forming the equatorial plane, with the axial positions occupied by two O atoms of coordinated water mol-ecules. The btmf ligands link adjoining Mn(II) atoms into a zigzag chain along the a axis. The crystal structure is stabilized by inter-molecular O-H⋯N hydrogen bonds, which link the chains, forming a two-dimensional layer parallel to (10); O-H⋯Cl inter-actions link the layers, forming a three-dimensional network.