Effects of probiotic supplementation on 12 min run performance, mood management, body composition and gut microbiota in amateur marathon runners: A double-blind controlled trial.

Background: Probiotic supplementation has a positive effect on endurance exercise performance and body composition in athletes, but the underlying mechanisms remain unclear. Gut microbiota can provide measurable markers of immune function in athletes, and microbial composition analysis may be sensitive enough to detect stress and metabolic disorders caused by exercise. Methods: Nineteen healthy active amateur marathon runners (15 male and 4 female) with a mean age of 29.11 years volunteered to participate in this double-blind controlled study. Based on the performance of the Cooper 12-min running test (CRT), the participants were allocated into two groups to receive either a probiotic formulation comprising lactobacillus acidophilus and bifidobacterium longum (n = 10) or placebo containing maltodextrin (n = 9) for five weeks. Consistency of diet and exercise was ensured throughout the experimental period. Before and after the intervention, all participants were assessed for CRT, emotional stability and gastrointestinal symptoms, gut microbiota composition, body composition and magnetic resonance imaging (MRI) indicators of skeletal muscle microcirculation. Results: Compared to before the intervention, the probiotics group showed an increase in CRT score (2.88 ± 0.57 vs 3.01 ± 0.60 km, P＜0.05), significant improvement in GSRS and GIQLI (9.20 ± 4.64 vs 7.40 ± 3.24, 118.90 ± 12.30 vs 127.50 ± 9.85, P＜0.05), while these indicators remained unchanged in the control group, with a significant time-group interaction effect on gastrointestinal symptoms. Additionally, some MRI metabolic cycling indicators of the thigh skeletal muscle also changed in the probiotics group (P＜0.05). Regarding microbiota abundance, the probiotics group exhibited a significant increase in the abundance of beneficial bacteria and a significant decrease in the abundance of harmful bacteria post-intervention (P＜0.05). Conclusion: As a sports nutritional supplement, probiotics have the potential to improve athletic performance by optimizing the balance of gut microbiota, alleviating gastrointestinal symptoms.

Coherent detection of the rotational Doppler effect measurement based on triple Fourier transform.

In recent years, the rotational Doppler effect (RDE) has been widely used in rotational motion measurement. However, the performance of existing detection systems based on the RDE are generally limited by the drastic reduction of signal-to-noise ratio (SNR) due to the influence of atmospheric turbulence, partial obscuration of the vortex beam (VB) during propagation, and misalignment between the optical axis of VB and the rotational axis of the object, which poses a challenge for practical applications. In this paper, we proposed a coherent detection method of the RDE measurement based on triple Fourier transform. First, the weak RDE signal in backscattered light is amplified by using the balanced homodyne detection method, and the amplified signal still retains the same characteristic of severe broadening in the frequency domain as the original signal. Furthermore, we proposed the triple Fourier transform to extract the broadened RDE frequency shift signal after the coherent amplification. The proposed method significantly improves the SNR of RDE measurement and facilitates the accurate extraction of rotational speed, which helps to further improve the RDE detection range and promote its practical application.

Analysis of rotational Doppler shift with multi-ring vortex beams.

Vortex beams (VBs) with orbital angular momentum have shown great potential in the detection of transverse rotational motion of spatial targets which is undetectable in the classical radar scheme. However, most of the reported rotational Doppler measurements based on VBs can only be realized under ideal experimental conditions. The long-range detection is still a challenge. The detection distance based on rotational Doppler effect (RDE) is mainly limited by the scattered signal's signal-to-noise ratio (SNR). In this work, we investigated the influence of multi-ring vortex beams (MVBs) on the rotational Doppler frequency spectrum of scattered light from an object based on RDE and proposed a method of SNR enhancement of RDE signal. Firstly, different types of MVBs composed of a set of single-ring VBs with the same topological charge and different radii are designed, including multi-ring Laguerre Gaussian beam (MLGB), multi-ring perfect vortex beams (MPVB), and high-order Laguerre Gaussian beam (HLGB). Then, the influence of the number of rings and radial radius interval on the intensity profiles of MVBs and rotational Doppler frequency spectra under aligned and misaligned conditions is studied in detail. And the reasons why different types of MVBs lead to different SNR enhancement effectiveness with the increase of rings are also analyzed theoretically. Finally, proof-of-concept experiments were conducted to verify the effectiveness of the SNR enhancement method for RDE signals. The results showed that the amplitudes of the Doppler spectra generated by the MLGB and MPVB are improved substantially with the increase of rings, but the enhancement effect caused by the former is superior to the latter. The gain of HLGB on the RDE signal is the lowest. This study provides a useful reference for the optimization of rotational Doppler detection systems and may be of great application value in telemetry, long-range communication and optical imaging.

Simultaneous measurement of spin and precession based on light's orbital angular momentum.

The rotational Doppler effect of the vortex beam is a recently emerged promising application of the optical vortex with orbital angular momentum. In this paper, we combine the method of the micro-Doppler effect of the traditional radar and the rotational Doppler effect of the vortex beam and propose an approach of rotational micro-Doppler effect, realizing the simultaneous measurement of spin and precession. We firstly analyze the rotational micro-Doppler characteristic introduced by precession under the illuminating of vortex beam and calculate the rotational micro-Doppler parameters related to the spin and precession. Then we conduct an experiment of using the vortex beam to detect a spinning object with precession and the rotational micro-Doppler frequency is successfully observed. By extracting the rotational micro-Doppler parameters, the simultaneous and independent measurement of spin and precession is realized. Both the theoretical analysis and experimental results indicate that the rotational micro-Doppler effect is an effective extension of the rotational Doppler effect and is also a feasible application of the vortex beam detection.

Constructing maps between distinct cell fates and parametric conditions by systematic perturbations.

MOTIVATION: Cell fate transitions are common in many developmental processes. Therefore, identifying the mechanisms behind them is crucial. Traditionally, due to complexity of networks and existence of plenty of kinetic parameters, dynamical analysis of biomolecular networks can only be performed by simultaneously perturbing a small number of parameters. Although many efforts have focused on how cell states change under specific perturbations, conversely, how to infer parametric conditions underlying distinct cell fates by systematic perturbations is less clear and needs to be further investigated. RESULTS: In this article, we present a general computational method by integrating systematic perturbations, unsupervised clustering, principal component analysis, and fitting analysis. The method can be used to to construct maps between distinct cell fates and parametric conditions by systematic perturbations. In particular, there are no needs of accurate parameter measurements and occurrence of bifurcations to establish the maps. To validate feasibility and inference performance of the method, we use toggle switch, inner cell mass, and epithelial mesenchymal transition as model systems to show how the maps are constructed and how system parameters encode essential information on cell fates. The maps tell us how systematic perturbations drive cell fate decisions and transitions, and allow us to purposefully predict, manipulate, and even control cell states. The approach is especially helpful in understanding crucial roles of certain parameter combinations during fate transitions. We hope that the approach can provide us valuable information on parametric or perturbation conditions so some specific targets, e.g. directional differentiation, can be realized. AVAILABILITY AND IMPLEMENTATION: No public data are used. The data we used are generated by randomly chosen values of model parameters in certain ranges, and the corresponding parameters are already attached in supplementary materials.

Matrix stability and bifurcation analysis by a network-based approach.

In this paper, we develop a network-based methodology to investigate the problems related to matrix stability and bifurcations in nonlinear dynamical systems. By matching a matrix with a network, i.e., interaction graph, we propose a new network-based matrix analysis method by proving a theorem about matrix determinant under which matrix stability can be considered in terms of feedback loops. Especially, the approach can tell us how a node, a path, or a feedback loop in the interaction graph affects matrix stability. In addition, the roles played by a node, a path, or a feedback loop in determining bifurcations in nonlinear dynamical systems can also be revealed. Therefore, the approach can help us to screen optimal node or node combinations. By perturbing them, unstable matrices can be stabilized more efficiently or bifurcations can be induced more easily to realize desired state transitions. To illustrate feasibility and efficiency of the approach, some simple matrices are used to show how single or combinatorial perturbations affect matrix stability and induce bifurcations. In addition, the main idea is also illustrated through a biological problem related to T cell development with three nodes: TCF-1, GATA3, and PU.1, which can be considered to be a three-variable nonlinear dynamical system. The approach is especially helpful in understanding crucial roles of single or molecule combinations in biomolecular networks. The approach presented here can be expected to analyze other biological networks related to cell fate transitions and systematic perturbation strategy selection.

Identifying key factors in cell fate decisions by machine learning interpretable strategies.

Cell fate decisions and transitions are common in almost all developmental processes. Therefore, it is important to identify the decision-making mechanisms and important individual molecules behind the fate decision processes. In this paper, we propose an interpretable strategy based on systematic perturbation, unsupervised hierarchical cluster analysis (HCA), machine learning (ML), and Shapley additive explanation (SHAP) analysis for inferring the contribution and importance of individual molecules in cell fate decision and transition processes. In order to verify feasibility of the approach, we apply it to the core epithelial to mesenchymal transition (EMT)-metastasis network. The key factors identified in EMT-metastasis are consistent with relevant experimental observations. The approach presented here can be applied to other biological networks to identify important factors related to cell fate decisions and transitions.

A Co-Expressed Natural Antisense RNA FCER1A-AS Controls IgE-Dependent Immunity by Promoting Expression of FcεRIα.

As the α-subunit of the high-affinity receptor for the Fc portion of immunoglobulin E (FcεRIα), FcεRIα plays a central role in IgE-mediated allergic disorders and in the immunity and immunopathology of some parasitic infections. FcεRIα is specifically expressed on basophils and mast cells, but the mechanism that controls FcεRIα expression in these cells is poorly understood. In this study, we found that the natural antisense transcript (NAT) of FcεRIα (FCER1A-AS) is co-expressed with the sense transcript (FCER1A-S) in both interleukin (IL)-3-induced FcεRIα-expressing cells and in the high FcεRIα-expressing cell line MC/9. When FCER1A-AS is selectively knocked down by the CRISPR/RfxCas13d (CasRx) approach in MC/9 cells, the expression of both FCER1A-S mRNA and proteins is markedly decreased. Furthermore, FCER1A-AS deficiency was also found to be associated with a lack of FCER1A-S expression in vivo. Correspondingly, homozygous mice deficient in FCER1A-AS demonstrated a similar phenotype to FCER1A knockout mice in Schistosoma japonicum infection and in IgE-FcεRIα-mediated cutaneous anaphylaxis. Thus, we uncovered a novel pathway for the control of FcεRIα expression by its co-expressed natural antisense transcript. IMPORTANCE FcεRIα is responsible for high-affinity binding with the Fc portion of IgE, which is critical for IgE-dependent disease responses such as allergy responses and anti-parasite immunity. FcεRIα is expressed on a few cell types, including mast cells and basophils. Although the expression of FcεRIα is known to be promoted by the IL-3-GATA-2 pathway during its differentiation, the mechanism by which FcεRIα expression is maintained remains unknown. In this study, we discovered that a natural antisense transcript, FCER1A-AS, is co-expressed with the sense transcript. The presence of FCER1A-AS is essential for sense transcript expression in mast cells and basophils, but not for the differentiation of these cells through cis-regulation. Like FcεRIα knockout mice, mice lacking FCER1A-AS also exhibit reduced survival after Schistosoma japonicum infection and a lack of IgE-mediated cutaneous anaphylaxis. Thus, a novel pathway for regulating IgE-mediated allergic diseases through noncoding RNAs has been revealed.

A neglected pathway for the accretion products formation in the atmosphere.

Highly oxygenated organic molecules (HOM) formed by the autoxidation of α-pinene initiated by OH radicals play an important role in new particle formation. It is believed that the accretion products, ROOR´, formed by the self- and cross-reaction of peroxy radicals (RO2 + R'O2 reactions), have extremely low volatility and are more likely to participate in nucleation. However, the mechanism of ROOR´ formation has not been fully demonstrated by experiment or theoretical calculation. Herein, we propose a novel mechanism of RO2 reacting with α-pinene (RO2 + α-pinene reactions) that have much lower potential barriers and larger rate constants than the reaction of RO2 with R'O2, which explains the ROOR´ formation found in the mass spectrometry experiments. The ROOR´ resulting from the reaction of RO2 with α-pinene can produce HOM dimers and trimers with a higher oxygen-to­carbon (O/C) ratio through a autoxidation chain. We also demonstrated that the presence of NOx and HO2 radical will reduce the RO2 concentration, but cannot completely inhibit the formation of HOM monomers and ROOR´. Even if one or both of RO2 radicals are acyl peroxy radicals (RC(O)O2), the potential barriers of the reactions between RC(O)O2 and α-pinene (RC(O)O2 + α-pinene reactions) are lower than that of RO2 reacting with RC(O)O2 (RO2 + RC(O)O2 reactions) or RC(O)O2 self-reactions (RC(O)O2 + RC(O)O2 reactions). The current work revealed, for the first time, a mechanism of RO2/RC(O)O2 reacting with α-pinene in the atmosphere, which provides new insight into the atmospheric chemistry of accretion products as SOA precursors.

Effects of oestrogen on vulvovaginal candidosis.

As a frequently occurring infectious disease mainly caused by Candida albicans, vulvovaginal candidosis (VVC) affects more than 100 million women worldwide every year. Multiple factors that influence C. albicans colonisation have been linked to the incidence of VVC, including high levels of circulating oestrogen due to pregnancy, the use of oral contraceptives, and hormone replacement therapy. This review provides an overview of the current understanding of the mechanism(s) by which oestrogen contributes to VVC, which might provide meaningful guidance to the prevention and treatment of this disease.

Hsa_circ_0010957 knockdown attenuates lipopolysaccharide-induced HK2 cell injury by regulating the miR-1224-5p/IRAK1 axis.

Circular RNAs (circRNAs) are involved in the progression of various diseases, including lupus nephritis. Hsa_circ_0010957 is reported to be dysregulated in lupus nephritis, but the exact function of this circRNA is unknown. This research aims to study the function and mechanism of circRNA hsa_circ_0010957 in a lipopolysaccharide (LPS)-induced cellular model of lupus nephritis. Human renal proximal tubular cell line HK2 cells were challenged by LPS. Hsa_circ_0010957, microRNA-1224-5p (miR-1224-5p), and interleukin-1 receptor-associated kinase 1 (IRAK1) abundances were examined by quantitative reverse transcription polymerase chain reaction or western blot. LPS-induced damage was evaluated via cell viability, apoptosis, inflammatory response and oxidative injury. The target interaction was analyzed by dual-luciferase reporter analysis and RNA immunoprecipitation. Hsa_circ_0010957 abundance was enhanced in LPS-challenged HK2 cells. Hsa_circ_0010957 knockdown alleviated LPS-induced apoptosis, the inflammatory response and oxidative injury in HK2 cells. MiR-1224-5p was targeted by hsa_circ_0010957, and miR-1224-5p knockdown reversed the influence of hsa_circ_0010957 silence on LPS-induced injury. IRAK1 was targeted via miR-1224-5p, and hsa_circ_0010957 could regulate IRAK1 by miR-1224-5p. MiR-1224-5p overexpression could mitigate LPS-induced apoptosis, the inflammatory response and oxidative injury, and this effect was abolished by IRAK1. Hsa_circ_0010957 silence weakened LPS-induced HK2 cell apoptosis, the inflammatory response and oxidative injury via regulating the miR-1224-5p/IRAK1 axis.

Interleukin-4- and NACHT, LRR and PYD domains-containing protein 3-independent mechanisms of alum enhanced T helper type 2 responses on basophils.

Aluminium hydroxide (alum), the most widely used adjuvant in human and animal vaccines, has long been known to promote T helper type 2 (Th2) responses and Th2-associated humoral responses, but the mechanisms have remained poorly understood. In this study, we explored whether alum is able to directly modulate antigen-presenting cells to enhance their potency for Th2 polarization. We found that alum treatment of dendritic cells failed to show any Th2-promoting activities. In contrast, alum was able to enhance the capacity of basophils to induce Th2 cells. When basophils from interleukin-4 (IL-4) knockout mice were examined, the intrinsic Th2-promoting activities by basophils were largely abrogated, but the alum-enhanced Th2-promoting activities on basophils were still detectable. More importantly, Th2-promoting adjuvant activities by alum found in IL-4 knockout mice were also largely reduced when basophils were depleted by antibody administration. Therefore, basophils can mediate Th2-promoting activities by alum both in vitro and in vivo through IL-4-independent mechanisms. Further studies revealed that secreted soluble molecules from alum-treated basophils were able to confer the Th2-promoting activities, and neutralization of thymic stromal lymphopoietin or IL-25 attenuated the IL-4-independent development of Th2 cells elicited by alum-treated basophils. Finally, alum was able to activate NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome in murine basophils in the same way as alum in professional antigen-presenting cells, but NLRP3 was not required for Th2-promoting activities on basophils by alum in vitro. These results demonstrated that alum can enhance the capacities of basophils to polarize Th2 cells via IL-4- and NLRP3-independent pathways.