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Using the first-principles theory, the geometric and electronic properties of the Ru-doped PtTe2 (Ru-PtTe2) monolayer, and its sensing performance for three VOCs biomarkers, namely, 2-propenal (C3H4O), acetone (C3H6O) and isoprene (C5H8), were analyzed, to expound its potential for exhaled breath analysis and diagnosis of lung cancer. It was found that the Ru-substitution on the surface of the pristine PtTe2 surface with a Te atom is energy-favorable, with the formation energy of −1.22 eV. Upon adsorption of the three VOC gas species, chemisorption was identified with the adsorption energies of −1.72, −1.12 and −1.80 eV for C3H4O, C3H6O and C5H8, respectively. The Ru-doping results in a strong magnetic property for the PtTe2 monolayer, whereas the gas adsorption eliminates this magnetic behavior. The electronic properties reveal the sensing mechanism of the Ru-PtTe2 monolayer for gas detection, and the bandgap change indicates its admirable positive sensing response for the three gas species. Therefore, we conclude that the Ru-PtTe2 monolayer is a promising sensing material to realize the diagnosis of lung cancer through exhaled gas detection, with a remarkable decrease in its electrical conductivity. This work paves the way for further exploration of the PtTe2-based gas sensor for early diagnosis of lung cancer, and we hope that more sensing materials can be investigated using the PtTe2 monolayer. [ABSTRACT FROM AUTHOR]

Summary: Butenyl‐spinosyn, a promising biopesticide produced by Saccharopolyspora pogona, exhibits stronger insecticidal activity and a broader pesticidal spectrum. However, its titre in the wild‐type S. pogona strain is too low to meet the industrial production requirements. Deletion of non‐target natural product biosynthetic gene clusters resident in the genome of S. pogona could reduce the consumption of synthetic precursors, thereby promoting the biosynthesis of butenyl‐spinosyn. However, it has always been a challenge for scientists to genetically engineer S. pogona. In this study, the Latour gene knockout system (linear DNA fragment recombineering system) was established in S. pogona. Using the Latour system, a hybrid NRPS‐T1PKS cluster (˜20 kb) which was responsible for phthoxazolin biosynthesis was efficiently deleted in S. pogona. The resultant mutant S. pogona‐Δura4‐Δc14 exhibited an extended logarithmic phase, increased biomass and a lower glucose consumption rate. Importantly, the production of butenyl‐spinosyn in S. pogona‐Δura4‐Δc14 was increased by 4.72‐fold compared with that in the wild‐type strain. qRT‐PCR analysis revealed that phthoxazolin biosynthetic gene cluster deletion could promote the expression of the butenyl‐spinosyn biosynthetic gene cluster. Furthermore, a TetR family transcriptional regulatory gene that could regulate the butenyl‐spinosyn biosynthesis has been identified from the phthoxazolin biosynthetic gene cluster. Because dozens of natural product biosynthetic gene clusters exist in the genome of S. pogona, the strategy reported here will be used to further promote the production of butenyl‐spinosyn by deleting other secondary metabolite synthetic gene clusters. [ABSTRACT FROM AUTHOR]

Considerable researches have proved that, to a great extent, high death rate of lung cancer is on account of its crypticity in the early stage, and detection of typical exhaled gases of possible patients has emerged as an effective and workable method to realize the prognosis of lung cancer. In this paper, the adsorption of the three typical exhaled components, namely, C6H6, C8H8, and C5H8, of lung cancer patients on the anatase TiO2 (101) surface was simulated based on the density functional theory method in order to recommend TiO2 nanotube arrays as sensing materials to fulfill this aim. Analysis based on adsorbing parameters, frontier molecular orbital theory, and density of states congruously implies that the anatase TiO2 (101) surface possesses certain sensitivity to these three gases, especially to C8H8 which possesses the best activity to be adsorbed on the proposed surface. Our experimental study showed great consensus with the theoretical calculations. Therefore, TiO2 nanotube arrays can be applied as proper gas-sensing material for the preparation of lung cancer prognosis sensors as a family device to realize the simple and convenient detection of lung cancer in our daily life. [ABSTRACT FROM AUTHOR]

A novel synthesis route for telithromycin was developed based on a 11,12-cylic carbonate protection strategy to prevent formation of 9,12-hemiacetal by-product. Through a 11,12-carbonate-6-O-methylerythromycin intermediate, telithromycin was synthesised from 6-O-methylerythromycin in five steps with 33% overall yield. [ABSTRACT FROM AUTHOR]

Flower appearance stands as a key characteristic of flowering plants and is closely linked to their ornamental value. Phytohormone Gibberellin (GA), essential for plant growth and development are widely reported for expansion in flower. DELLA proteins are known to negatively regulate GA signaling and influences plant growth and development through the regulation of cell expansion. However, the specific biological function of DELLA proteins in the woody plant Osmanthus fragrans remains unclear. In this study, O. fragrans 'Sijigui' was utilized as the experimental material, and OfRGA was isolated using the PCR method. OfRGA is expressed in various tissues and is localized in the nucleus. A negative association was observed between OfRGA expression and petal size across four different Osmanthus fragrans cultivars. Transformation experiments in tobacco revealed that transgenic plants overexpressing OfRGA exhibited increased plant height, greater node spacing, shorter leaf length, and wider leaves during the vegetative phase. Notably, the flower organs of transgenic tobacco plants displayed noticeable alterations, including reduced petal size, shorter corolla tubes, pedicels, male and female stamens, and lighter petal color. Furthermore, a decrease in the length and area of petal and corolla tube cells was observed as well. DEGs were found in RNA-seq studies of OfRGA transgenic plants. Subsequent investigation revealed a considerable quantity of down-regulated genes were associated with cell wall synthesis genes and expansion genes, such as CesA1 , XEH , and EXPB1 , as well as genes related to anthocyanin biosynthesis. Overall, our findings suggest that OfRGA undermines tobacco petal size by influencing cell expansion. The present study offers a fundamental comprehension of the role of DELLA protein in the organ development in Osmanthus fragrans., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wan, Lu, Jiang, Shao, Chen, Yang, Khan, Deng, Zhong, Wang, Xiao, Fang and Zhao.)

This study aimed to compare the measuring stereopsis results of unilateral amblyopia during amblyopic treatment by employing some of the most widely used clinical tests. Thirty-four individuals with previously untreated unilateral amblyopia, aged 8.4 ± 2.7 years, were included in the study. Monocular (best corrected visual acuity [BCVA] at distance) and binocular (including Titmus, Random-dot, and Frisby stereopsis) visual functions were measured at baseline and 2-month and 6-month visits after synthetical treatment. We found that Titmus stereopsis was always significantly better than Random-dot stereopsis (p < 0.001). Frisby stereopsis was also always significantly better than Random-dot stereopsis (p < 0.001). However, there was no significant difference between Titmus stereopsis and Frisby stereopsis (p = 0.562). However, interestingly, there was no significant difference in the mean improvement of the three stereopsis methods from baseline to the 2-month visit, F = 1.158, p = 0.318. Similarly, a significant difference was also lacking in the mean improvement of the three stereopsis methods from baseline to the 6-month visit, F = 0.302, p = 0.740. We conclude that there will be different results obtained from different stereopsis measuring methods used to measure amblyopia in patients. We recommend performing at least two types of stereoscopic measurements to evaluate each case of amblyopia. However, for observing therapeutic effects, each measurement method has the same performance for clinical results during amblyopic treatment.

Nanosensor-based patient exhaled breath detection is a practical and effective way to detect lung cancer early. In this paper, a Ru-doped MoS 2 monolayer (Ru-MoS 2 ) is proposed as a promising novel biosensor based on first-principles theory for the detection of three typical early stage lung cancer exhaled volatile organic compounds, namely, C 3 H 4 O, C 3 H 6 O, and C 5 H 8 . Replacement of a S atom in the MoS 2 monolayer with a Ru dopant atom to form a stable Ru-MoS 2 monolayer with a binding energy of -4.78 eV is further demonstrated by the thermostability and chemical stability analysis as well as improving the adsorption performance of the system for three VOCs. The adsorption configuration structures, adsorption properties, and electronic behavior of the Ru-MoS 2 monolayer are investigated by electron deformation density and density of states analysis to gain a comprehensive understanding of the physicochemical properties as sensing material. The results show that the adsorption energies of the Ru-MoS 2 monolayer for C 3 H 4 O, C 3 H 6 O, and C 5 H 8 are 3.42, -1.53, and -2.80 eV, respectively, all of which are chemisorption with excellent adsorption performance. The sensitivities for the three VOCs could be up to 1.09, 140.50, and 5.90, respectively, and the band structure and work function further elucidate the sensing mechanism of the Ru-MoS 2 monolayer as a resistive gas sensor. The type and concentration of these exhaled breaths may reflect changes in the patient's physiological and biochemical status and may serve as a probe for the diagnosis of lung cancer. The results in this work could provide a guidance for researchers to explore the practical applications in the early diagnosis of lung cancer by gas sensors., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Objective. Head motion correction (MC) is an essential process in brain positron emission tomography (PET) imaging. We have used the Polaris Vicra, an optical hardware-based motion tracking (HMT) device, for PET head MC. However, this requires attachment of a marker to the subject's head. Markerless HMT (MLMT) methods are more convenient for clinical translation than HMT with external markers. In this study, we validated the United Imaging Healthcare motion tracking (UMT) MLMT system using phantom and human point source studies, and tested its effectiveness on eight 18 F-FPEB and four 11 C-LSN3172176 human studies, with frame-based region of interest (ROI) analysis. We also proposed an evaluation metric, registration quality ( RQ ), and compared it to a data-driven evaluation method, motion-corrected centroid-of-distribution (MCCOD). Approach. UMT utilized a stereovision camera with infrared structured light to capture the subject's real-time 3D facial surface. Each point cloud, acquired at up to 30 Hz, was registered to the reference cloud using a rigid-body iterative closest point registration algorithm. Main results. In the phantom point source study, UMT exhibited superior reconstruction results than the Vicra with higher spatial resolution (0.35 ± 0.27 mm) and smaller residual displacements (0.12 ± 0.10 mm). In the human point source study, UMT achieved comparable performance as Vicra on spatial resolution with lower noise. Moreover, UMT achieved comparable ROI values as Vicra for all the human studies, with negligible mean standard uptake value differences, while no MC results showed significant negative bias. The RQ evaluation metric demonstrated the effectiveness of UMT and yielded comparable results to MCCOD. Significance. We performed an initial validation of a commercial MLMT system against the Vicra. Generally, UMT achieved comparable motion-tracking results in all studies and the effectiveness of UMT-based MC was demonstrated., (Creative Commons Attribution license.)

Cell division is fundamental to all cellular life. Most of the archaea employ one of two alternative division machineries, one centered around the prokaryotic tubulin homolog FtsZ and the other around the endosomal sorting complex required for transport (ESCRT). However, neither of these mechanisms has been thoroughly characterized in archaea. Here, we show that three of the four PRC (Photosynthetic Reaction Center) barrel domain proteins of Haloferax volcanii (renamed Cell division proteins B1/2/3 (CdpB1/2/3)), play important roles in division. CdpB1 interacts directly with the FtsZ membrane anchor SepF and is essential for division, whereas deletion of cdpB2 and cdpB3 causes a major and a minor division defect, respectively. Orthologs of CdpB proteins are also involved in cell division in other haloarchaea. Phylogenetic analysis shows that PRC barrel proteins are widely distributed among archaea, including the highly conserved CdvA protein of the crenarchaeal ESCRT-based division system. Thus, diverse PRC barrel proteins appear to be central to cell division in most if not all archaea. Further study of these proteins is expected to elucidate the division mechanisms in archaea and their evolution.

Objectives: The mechanism for traditional Chinese medicine in treating of recurrent spontaneous abortion is not clear. This study aims to explore the mechanism of baotaiyin in the treatment of recurrent abortion by regulating the immune inflammatory axis of interleukin (IL)-23/helper T cell (Th)17., Methods: Spontaneous abortion model mice were randomly divided into a model group, 3 dose (low, medium, and high) groups of baotaiyin, with 10 mice in each group. After 14 days of medication, the levels of IL-17, IL-23, IL-10, and TGF-β in serum were detected with enzyme-linked immunosorbent assay. The proportion of Th17 and regulatory T cells (Treg) cells in spleen lymphocytes was tested with flow cytometry. The expressions of (retinoid-related orphan receptor γt, ROR-γt) and forkhead box P3 (FOXP3) mRNA in decidua tissues was detected with RT-PCR. Embryo absorption rate was counted., Results: Compared with the model group, the absorption rate of embryo and Th17/Treg cell ratio in baotaiyin medium- and high-dose groups were decreased significantly (all P<0.05); the levels of IL-17 and IL-23 in serum were decreased (both P<0.05), while the levels of TGF-β and IL-10 in baotaiyin medium- and high-dose groups were increased (P<0.05, P<0.01, respectively); the expression of ROR-γt mRNA was decreased and the expression of FOXP3 mRNA was increased (all P<0.01) in decidua tissues of baotaiyin medium- and high-dose groups., Conclusions: Baotaiyin inhibits the positive feedback cycle of IL-23/Th17 immune inflammatory axis, which regulates Th17/Treg cell balance, mediates the maternal and fetal immune tolerance, and prevents the recurrent abortion.

Butenyl-spinosyn is a highly effective and broad-spectrum biopesticide produced by Saccharopolyspora pogona . However, the yield of this compound is difficult to increase because the regulatory mechanism of secondary metabolism is still unknown. Here, the transcriptional regulator Sp13016 was discovered to be highly associated with butenyl-spinosyn synthesis and bacterial growth. Overexpression of sp13016 improved butenyl-spinosyn production to a level that was 2.84-fold that of the original strain, while deletion of sp13016 resulted in a significant decrease in yield and growth inhibition. Comparative proteomics revealed that these phenotypic changes were attributed to the influence of Sp13016 on the central carbon metabolism pathway to regulate the supply of precursors. Our research helps to reveal the regulatory mechanism of butenyl-spinosyn biosynthesis and provides a reference for increasing the yield of natural products of Actinomycetes .

The multi-bounce laser microphone utilizes optical methods to detect the displacement of a gold-covered thin film diaphragm caused by ultrasound signal pressure waves. This sensitive all-optical sensing technique provides new opportunities for advanced ultrasound imaging as it is expected to achieve a higher detection signal-to-noise ratio (SNR) in a broader spectrum, as compared to conventional ultrasonic transducers. The technique does not involve signal time-averaging and the real-time enhancement in detection SNR stems from the amplification of signal strength due to multiple bouncing off the diaphragm. The system was previously developed for detecting acoustic signatures generated by explosives and were limited to lower than 10 kHz in frequency. To demonstrate its feasibility for biomedical imaging applications, preliminary experiments were conducted to show high fidelity detection of ultrasound waves with frequencies ranging from 100 kHz to in excess of 1 MHz. Experimental results are also presented in this work demonstrating the improved detection sensitivity of the multi-bounce laser microphone in detecting ultrasound signals when compared with a commercial Fabry-Perot type optical hydrophone. Furthermore, we also applied the multi-bounce laser microphone to detect photoacoustic signatures emitted by India ink when a LED bar is used as the excitation source without signal averaging.

Realizing the diagnosis of lung cancer at an inchoate stage is significant to get valuable time to conduct curative surgery. In this work, we relied on a density functional theory (DFT)-proposed Ru-SnS 2 monolayer as a novel, promising biosensor for lung cancer diagnosis through exhaled gas analysis. The results indicated that the Ru-SnS 2 monolayer has admirable adsorption performance for three typical volatile organic compounds (VOCs) of lung cancer patients, which therefore results in a remarkable change in the electronic behavior of the Ru-doped surface. As a consequence, the conductivity of the Ru-SnS 2 monolayer increases after gas adsorption based on frontier molecular orbital theory. This provides the possibility to explore the Ru-SnS 2 monolayer as a biosensor for lung cancer diagnosis at an early stage. In addition, the desorption behavior of three VOCs from the Ru-SnS 2 surface is studied as well. Our calculations aim at proposing novel sensing nanomaterials for experimentalists to facilitate the progress in lung cancer prognosis., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)