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1.
Technol Health Care ; 2024 Apr 30.
Article de Anglais | MEDLINE | ID: mdl-38759032

RÉSUMÉ

BACKGROUND: Investigating the secondary sepsis of pneumonia is of great significance for rapid diagnosis and early treatment of sepsis. OBJECTIVE: This study aimed to investigate the predictive value of micro ribonucleic acids (miRNA) 7110-5p and miR-223-3p in sepsis secondary to pneumonia. A miRNA microarray was used to analyze the differences in miRNA expression between patients with pneumonia and those with sepsis secondary to pneumonia. METHODS: The study included a total of 50 patients with pneumonia and 42 patients with sepsis secondary to pneumonia. Quantitative polymerase chain reaction analysis was conducted to measure the circulating miRNA expression levels in patients and assess their correlations with clinical characteristics and prognosis. In this study, nine miRNAs - hsa-miR-4689-5p, hsa-miR-4621-5p, hsa-miR-6740-5p, hsa-miR-7110-5p, hsa-miR-765, hsa-miR-940, hsa-miR-213-5p, hsa-miR-223-3p, and hsa-miR-122 - met the screening criteria of having a fold change ⩾ 2 or < 0.5; p< 0.01 indicated significant differences in the results. RESULTS: The expression levels of miR-7110-5p and miR-223-3p differed between the two patient groups, being up-regulated in the plasma of patients with sepsis secondary to pneumonia. miR-7110-5p and miR-223-3p showed higher expression levels in both patients with pneumonia and sepsis compared to healthy controls. Moreover, the receiver operating characteristic curve revealed that the areas under the curve for predicting pneumonia using miR-7110-5p were 0.781 while those for predicting sepsis secondary to pneumonia were 0.862. For miR-223-3p, the corresponding values for predicting pneumonia and sepsis secondary to pneumonia were 0.879 and 0.924, respectively. However, there were no significant differences in the levels of miR-7110-5p and miR-223-3p between the plasma of survived and deceased patients with sepsis. CONCLUSIONS: MiR-7110-5p and miR-223-3p have the potential to serve as biological indicators for predicting sepsis secondary to pneumonia.

3.
Rev Sci Instrum ; 95(5)2024 May 01.
Article de Anglais | MEDLINE | ID: mdl-38717264

RÉSUMÉ

Deep network fault diagnosis methods heavily rely on abundant labeled data for effective model training. However, small-sized samples and imbalanced samples often lead to insufficient features, resulting in accuracy degradation and even instability in the diagnosis model. To address this challenge, this paper introduces a coupled adversarial autoencoder (CoAAE) based on the Bayesian method. This model aims to solve the issue of insufficient samples by generating fake samples and integrating them with the original ones. Within the CoAAE framework, the probability density distribution of the original data is captured using an encoder and fake samples are generated by random sampling from this distribution and decoding them. This process is the adversarial interaction between the encoder and a classifier to obtain the prior distribution of the encoder's parameters. The encoder's parameters are updated through the decoder's reconstruction process, leading to the posterior distribution. Concurrently, the decoder is trained to enhance its ability to reconstruct samples accurately. To address the imbalance in the original samples, a parallel coupled network is employed. This network shares the weights of the extraction layer in the encoder, enabling it to learn the joint distribution between fault-related and normal samples. To evaluate the effectiveness of the proposed data augmentation method, experiments were conducted on a bearing database from Case Western Reserve University using ResNet18 as the deep learning diagnosis model representative. The results demonstrate that CoAAE can effectively augment imbalanced datasets and outperform other advanced methods.

4.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-38602461

RÉSUMÉ

Intelligent diagnostic algorithms based on convolutional neural networks (CNNs) have shown great potential in diagnosing various conditions. However, accurately and robustly diagnosing faults in noisy situations remains challenging. This study presents an adaptive fully convolutional network (AFCN) for identifying bearing defects in noisy environments. First, we use a novel large kernel convolution method for high-frequency noise reduction and wide-area temporal feature extraction. By utilizing a sequence of stacked residual adaptive convolution blocks, the AFCN achieves a selective emphasis on significant features and adaptive adjustment of feature weights at various convolution scales. The experimental results have shown that the AFCN achieves a diagnostic accuracy of over 90% for the faults in the CWRU dataset under the -8 dB noise and over 77% for the PU dataset in the case of -6 dB noise. The comparison results with five advanced baseline models have demonstrated the superiority of the AFCN in feature extraction, noise immunity, and robustness to the noise environment. The AFCN provides a better adaption to noise interference than conventional CNNs and other advanced adaptive networks.

5.
Nano Lett ; 24(15): 4346-4353, 2024 Apr 17.
Article de Anglais | MEDLINE | ID: mdl-38587212

RÉSUMÉ

Ghost phonon polaritons (g-PhPs), a unique class of phonon polaritons in the infrared, feature ultralong diffractionless propagation (>20 µm) across the surface and tilted wavefronts in the bulk. Here, we study hybrid g-PhPs in a heterostructure of calcite and an ultrathin film of the phase change material (PCM) In3SbTe2, where the optical field is bound in the PCM film with enhanced confinement compared with conventional g-PhPs. Near-field optical images for hybrid g-PhPs reveal a lemniscate pattern in the momentum distribution. We fabricated In3SbTe2 gratings and investigated how different orientations and periodicities of gratings impact the propagation of hybrid g-PhPs. As the grating period decreases to zero, the wavefront of hybrid g-PhPs can be dynamically steered by varying the grating orientation. Our results highlight the promise of hybrid g-PhPs with tunable functionalities for nanophotonic studies.

6.
eLight ; 4(1): 6, 2024.
Article de Anglais | MEDLINE | ID: mdl-38585278

RÉSUMÉ

Nonlinear optical signal processing (NOSP) has the potential to significantly improve the throughput, flexibility, and cost-efficiency of optical communication networks by exploiting the intrinsically ultrafast optical nonlinear wave mixing. It can support digital signal processing speeds of up to terabits per second, far exceeding the line rate of the electronic counterpart. In NOSP, high-intensity light fields are used to generate nonlinear optical responses, which can be used to process optical signals. Great efforts have been devoted to developing new materials and structures for NOSP. However, one of the challenges in implementing NOSP is the requirement of high-intensity light fields, which is difficult to generate and maintain. This has been a major roadblock to realize practical NOSP systems for high-speed, high-capacity optical communications. Here, we propose using a parity-time (PT) symmetric microresonator system to significantly enhance the light intensity and support high-speed operation by relieving the bandwidth-efficiency limit imposed on conventional single resonator systems. The design concept is the co-existence of a PT symmetry broken regime for a narrow-linewidth pump wave and near-exceptional point operation for broadband signal and idler waves. This enables us to achieve a new NOSP system with two orders of magnitude improvement in efficiency compared to a single resonator. With a highly nonlinear AlGaAs-on-Insulator platform, we demonstrate an NOSP at a data rate approaching 40 gigabits per second with a record low pump power of one milliwatt. These findings pave the way for the development of fully chip-scale NOSP devices with pump light sources integrated together, potentially leading to a wide range of applications in optical communication networks and classical or quantum computation. The combination of PT symmetry and NOSP may also open up opportunities for amplification, detection, and sensing, where response speed and efficiency are equally important. Supplementary Information: The online version contains supplementary material available at 10.1186/s43593-024-00062-w.

7.
Opt Express ; 32(7): 12118-12126, 2024 Mar 25.
Article de Anglais | MEDLINE | ID: mdl-38571044

RÉSUMÉ

Microresonators facilitate enhanced light-matter interactions within a limited space, showing great promise for nonlinear optics. Here, we demonstrate a high-quality (Q) factor Fabry-Perot microresonator (FPR) for second harmonic generation (SHG) on an x-cut thin film lithium niobate (TFLN) platform. The FPR exhibits Q factors of Qpump = 1.09 × 105 and QSH = 1.15 × 104 at the 1560 nm pump wavelength and 780 nm second harmonic wavelength, respectively. Under low pump power, a normalized SHG efficiency of 158.5 ± 18.5%/W is attained. We experimentally verify that increased temperatures mitigate photorefractive effects that degrade SHG performance. This work highlights the immense capabilities of one-dimensional planar optical waveguide resonators for efficient on-chip nonlinear wavelength conversion.

8.
Opt Express ; 32(4): 6507-6519, 2024 Feb 12.
Article de Anglais | MEDLINE | ID: mdl-38439351

RÉSUMÉ

With the increasing demand for communication capacity, all-optical regeneration of multimode signals is a helpful technology of network nodes and optical signal processors. However, the difficulty of regenerating signal in higher-order modes hinders the practical application of multimode all-optical regenerators. In this study, we experimentally demonstrate the 40 Gb/s all-optical regeneration of NRZ-OOK signal in TE0 and TE1 modes via four-wave mixing (FWM) in the low-loss silicon-based nanowaveguide. By optimizing the parameters of waveguide section to enhance FWM conversion efficiency of two modes, and introducing Euler bending to reduce crosstalk between modes, the transmission loss of the silicon waveguide is 0.3 dB/cm, and the FWM conversion efficiency of the multimode regenerator is as high as -9.6 dB (TE0) and -13.0 dB (TE1). Both modes achieve extinction ratio enhancement of about 6 dB after regeneration. This silicon-based all-optical regenerator has great application potential in all-optical signal processing systems.

9.
Nat Nanotechnol ; 19(6): 758-765, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38429492

RÉSUMÉ

The discovery of ultraconfined polaritons with extreme anisotropy in a number of van der Waals (vdW) materials has unlocked new prospects for nanophotonic and optoelectronic applications. However, the range of suitable materials for specific applications remains limited. Here we introduce tellurite molybdenum quaternary oxides-which possess non-centrosymmetric crystal structures and extraordinary nonlinear optical properties-as a highly promising vdW family of materials for tunable low-loss anisotropic polaritonics. By employing chemical flux growth and exfoliation techniques, we successfully fabricate high-quality vdW layers of various compounds, including MgTeMoO6, ZnTeMoO6, MnTeMoO6 and CdTeMoO6. We show that these quaternary vdW oxides possess two distinct types of in-plane anisotropic polaritons: slab-confined and edge-confined modes. By leveraging metal cation substitutions, we establish a systematic strategy to finely tune the in-plane polariton propagation, resulting in the selective emergence of circular, elliptical or hyperbolic polariton dispersion, accompanied by ultraslow group velocities (0.0003c) and long lifetimes (5 ps). Moreover, Reststrahlen bands of these quaternary oxides naturally overlap that of α-MoO3, providing opportunities for integration. As an example, we demonstrate that combining α-MoO3 (an in-plane hyperbolic material) with CdTeMoO6 (an in-plane isotropic material) in a heterostructure facilitates collimated, diffractionless polariton propagation. Quaternary oxides expand the family of anisotropic vdW polaritons considerably, and with it, the range of nanophotonics applications that can be envisioned.

10.
Proc Natl Acad Sci U S A ; 121(12): e2319465121, 2024 Mar 19.
Article de Anglais | MEDLINE | ID: mdl-38466854

RÉSUMÉ

In conventional thin materials, the diffraction limit of light constrains the number of waveguide modes that can exist at a given frequency. However, layered van der Waals (vdW) materials, such as hexagonal boron nitride (hBN), can surpass this limitation due to their dielectric anisotropy, exhibiting positive permittivity along one optic axis and negativity along the other. This enables the propagation of hyperbolic rays within the material bulk and an unlimited number of subdiffractional modes characterized by hyperbolic dispersion. By employing time-domain near-field interferometry to analyze ultrafast hyperbolic ray pulses in thin hBN, we showed that their zigzag reflection trajectories bound within the hBN layer create an illusion of backward-moving and leaping behavior of pulse fringes. These rays result from the coherent beating of hyperbolic waveguide modes but could be mistakenly interpreted as negative group velocities and backward energy flow. Moreover, the zigzag reflections produce nanoscale (60 nm) and ultrafast (40 fs) spatiotemporal optical vortices along the trajectory, presenting opportunities to chiral spatiotemporal control of light-matter interactions. Supported by experimental evidence, our simulations highlight the potential of hyperbolic ray reflections for molecular vibrational absorption nanospectroscopy. The results pave the way for miniaturized, on-chip optical spectrometers, and ultrafast optical manipulation.

11.
Int J Environ Health Res ; : 1-18, 2024 Mar 27.
Article de Anglais | MEDLINE | ID: mdl-38544315

RÉSUMÉ

In this meta-analysis, we aimed to evaluate the prevalence of occupational hypersensitivity pneumonitis (OHP) among different occupations globally. Our search was conducted on MEDLINE via PubMed, Scopus, Web of Science, and Cochrane CENTRAL from inception to September 2023. Eligible studies were observational in nature and focused on several specific occupations. A total of 46 articles were included (n = 2,826,420 participants). The overall prevalence of OHP was found to be 4.2% (95% CI: 2.1% to 8.0%), but this varied significantly based on occupation and geographic location. Printers had the highest OHP prevalence at 57.14%, followed by tobacco workers (26.32%), and water-related workers (24.10%). South America showed the highest prevalence of 16.71%, compared to Asia (15.19%), and North America (8.52%). Significant variations in OHP prevalence by occupation and region were found, with the highest rates in printers and tobacco workers. Age and smoking were identified as contributing factors to the prevalence variability.

12.
Opt Express ; 32(2): 2179-2187, 2024 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-38297753

RÉSUMÉ

On-chip micro-ring resonators (MRRs) with low loss and large free spectral ranges (FSRs) are important for photonic devices. So far, ultra-low-loss silicon-nitride (Si3N4) waveguides are primarily fabricated in laboratories, as they often demand special processes to reduce transmission losses. While, Si3N4 waveguides fabricated by the standard multi-project wafer (MPW)-based processes often suffer from significant sidewall scattering, resulting in high scattering losses. Here, we present an innovative approach to photonics by introducing a compact and multi-mode structure. This approach significantly reduces the contact between the optical field and the rough sidewalls in the high-confinement Si3N4 waveguide. By incorporating modified Euler bends, and a weakly tapered gap directional coupler, adiabatic transmission with simultaneous ultra-low loss and compact size is achieved even in 7-µm wide waveguide. Results show that the intrinsic quality factor Qi of MRR is (6.8 ± 0.4) × 106 at the wavelength of 1550 nm, which is approximately four times higher than the previously reported by the same fabrication process. An ultra-low loss of 0.051 ± 0.003 dB/cm is achieved based on the standard LIGENTEC-AN800 technology. This accomplishment addresses a critical challenge in high-confinement waveguides. Our work provides new insights into the low propagation loss in Si3N4 waveguides and provides a broader prospect for integrated photonics in the ultra-high-Q regime.

13.
Sci Rep ; 14(1): 628, 2024 01 05.
Article de Anglais | MEDLINE | ID: mdl-38182736

RÉSUMÉ

Severe trauma could induce sepsis due to the loss of control of the infection, which may eventually lead to death. Accurate and timely diagnosis of sepsis with severe trauma remains challenging both for clinician and laboratory. Combinations of markers, as opposed to single ones, may improve diagnosis. We compared the diagnostic characteristics of routinely used biomarkers of sepsis alone and in combination, trying to define a biomarker panel to predict sepsis in severe patients. This prospective observational study included patients with severe trauma (Injury severity score, ISS = 16 or more) in the emergency intensive care unit (EICU) at a university hospital. Blood samples were collected and plasma levels of procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6) and serum amyloid A (SAA) were measured using commercial enzyme linked immunosorbent assay (ELISA) kits. A total of 100 patients were eligible for analysis. Of these, 52 were diagnosed with sepsis. CRP yielded the highest discriminative value followed by PCT. In multiple logistic regression, SAA, CRP, and PCT were found to be independent predictors of sepsis. Bioscore which was composed of SAA, CRP, and PCT was shown to be far superior to that of each individual biomarker taken individually. Therefore, compared with single markers, the biomarker panel of PCT, CRP, and SAA was more predictive of sepsis in severe polytrauma patients.


Sujet(s)
Protéine C-réactive , Sepsie , Humains , Procalcitonine , Protéine amyloïde A sérique , Marqueurs biologiques , Sepsie/diagnostic
14.
Int Wound J ; 21(1): e14652, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-38272793

RÉSUMÉ

The purpose of this study was to analyse the risk factors for sepsis in patients with trauma and develop a new scoring system for predicting sepsis in patients with trauma based on these risk factors. This will provide a simple and effective early warning method for the rapid and accurate detection and evaluation of the probability of sepsis in patients with trauma to assist in planning timely clinical interventions. We undertook a retrospective analysis of the clinical data of 216 patients with trauma who were admitted to the emergency intensive care unit of the emergency medicine department of the Hebei Medical University Third Hospital, China, between November 2017 and October 2022. We conducted a preliminary screening of the relevant factors using univariate logistic regression analysis and included those factors with a p value of <0.075 in the multivariate logistic regression analysis, from which the risk factors were screened and assigned, and obtained a total score, which was the sepsis early warning score. The incidence of sepsis in patients in the intensive care unit with trauma was 36.9%, and the mortality rate due to sepsis was 19.4%. We found statistically significant differences in several factors for patients with sepsis. The risk factors for sepsis in patients with trauma were the activated partial thromboplastin time, the New Injury Severity Score, growth differentiation factor-15 levels, shock, mechanical ventilation and the Acute Physiology and Chronic Health Evaluation II score. The area under the receiver operating characteristic curve of the sepsis early warning score for predicting sepsis in patients with trauma was 0.725. When the cutoff value of the early warning score was set at 5.0 points, the sensitivity was 69.9% and the specificity was 60.3%. The incidence of sepsis in patients with trauma can be reduced by closely monitoring patients' hemodynamics, implementing adequate fluid resuscitation promptly and by early removal of the catheter to minimize the duration of unnecessary invasive mechanical ventilation. In this study, we found that the use of the sepsis early warning score helped in a more accurate and effective evaluation of the prognosis of patients with trauma.


Sujet(s)
Sepsie , Humains , Études rétrospectives , Sepsie/diagnostic , Unités de soins intensifs , Courbe ROC , Patients , Pronostic
15.
Curr Pharm Des ; 30(1): 63-70, 2024.
Article de Anglais | MEDLINE | ID: mdl-38141193

RÉSUMÉ

BACKGROUND: Post-mastectomy lymphedema is a chronic progressive disease characterized by a significant reduction in quality of life and a range of complications. AIM: To this date, no single treatment method provides pathological correction of the mechanisms associated with tissue reorganization observed in later-stage breast cancer-related lymphedema (BCRL). METHODS: To define a personalized approach to the management of patients with iatrogenic lymphedema, we performed a systematic review of literature without a comprehensive meta-analysis to outline existing molecular- genetic patterns, overview current treatment methods and their efficacy, and highlight the specific tissue-associated changes in BCRL conditions and other bio-engineering approaches to develop personalized therapy. RESULTS: Our results show that several tissue-specific and pathological molecular markers may be found, yet current research does not aim to define them. CONCLUSION: As such, currently, a strong foundation for further research into molecular-genetic changes in lymphedema tissue exists, and further research should focus on finding specific targets for personalized treatment through bio-engineering approaches.


Sujet(s)
Lymphoedème après cancer du sein , Tumeurs du sein , Femelle , Humains , Bioingénierie , Lymphoedème après cancer du sein/thérapie , Lymphoedème après cancer du sein/étiologie , Tumeurs du sein/complications , Mastectomie/effets indésirables , Qualité de vie , Résultat thérapeutique
16.
Opt Express ; 31(22): 36736-36744, 2023 Oct 23.
Article de Anglais | MEDLINE | ID: mdl-38017817

RÉSUMÉ

High-efficiency second harmonic generation (SHG) relying solely on intermodal dispersion engineering remains a challenge. Here, we realize highly efficient SHG using a double-waveguide coupled racetrack microring resonator on X-cut lithium niobate on insulator (LNOI), where both pump and second harmonic (SH) approach critical coupling. Through precise temperature tuning, simultaneous pump and SH resonance is attained in the resonator, dramatically enhancing SHG efficiency. With low pump power, a normalized conversion efficiency of 9972%/W is achieved. Moreover, the resonator provides a 25.73 dB enhancement in SHG efficiency compared to a 4 mm straight waveguide with identical phase matching in our experiment. This work enables efficient wavelength conversion and quantum state generation on integrated X-cut LNOI platforms.

17.
Opt Lett ; 48(22): 5871-5874, 2023 Nov 15.
Article de Anglais | MEDLINE | ID: mdl-37966740

RÉSUMÉ

Recent advancements in optical convolutional neural networks (CNNs) and radar signal processing systems have brought an increasing need for the adoption of optical fast Fourier transform (OFFT). Presently, the fast Fourier transform (FFT) is executed using electronic means within prevailing architectures. However, this electronic approach faces limitations in terms of both speed and power consumption. Concurrently, existing OFFT systems struggle to balance the demands of large-scale processing and high precision simultaneously. In response, we introduce a novel, to the best of our knowledge, solution: a complex-valued matrix-vector system harnessed through wavelength selective switches (WSSs) for the realization of a 24-input optical FFT, achieving a high-accuracy level of 5.4 bits. This study capitalizes on the abundant wavelength resources available to present a feasible solution for an optical FFT system with a large N.

18.
Opt Lett ; 48(20): 5355-5358, 2023 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-37831866

RÉSUMÉ

Photon pairs generated by employing spontaneous nonlinear effects in microresonators are critically essential for integrated optical quantum information technologies, such as quantum computation and quantum cryptography. Microresonators featuring high-quality (Q) factors can offer simple yet power-efficient means to generate photon pairs, thanks to the intracavity field enhancement. In microresonators, it is known that the photon-pair generation rate (PGR) is roughly proportional to the cubic power of the Q factor. However, the upper limit on PGR is also set by the Q factor: a higher Q factor brings a longer photon lifetime, which in turn leads to a lower repetition rate allowing for photon flow emitted from the microresonator, constrained by the Fourier-transform limit. Exceeding this limit will result in the overlap of photon wave packets in the time domain, thus degrading the quantum character of single-photon light beams. To push the limit of PGR in a single resonator, we propose a method by harnessing the resonance linewidth-manipulated microresonators to improve the maximum achievable photon repetition rate while keeping the power efficiency. The maximum achievable PGR and power efficiency are thus balanced by leveraging the combination of low and high-Q resonances.

19.
Infect Drug Resist ; 16: 6691-6701, 2023.
Article de Anglais | MEDLINE | ID: mdl-37854469

RÉSUMÉ

Objective: We analyzed the characteristics and risk factors for pulmonary infection in patients with spinal cord injury who underwent tracheostomy and propose measures to help in early detection and intervention to reduce mortality and improve prognosis. Methods: We collected data retrospectively from January 1, 2018, to December 31, 2022. The inclusion criteria were: Patients aged 18 years or more with a spinal cord injury who underwent tracheostomy, were treated with mechanical ventilation for over 48 hours, and were diagnosed as having a pulmonary infection. Sputum samples were cultured and analyzed. Results: 101 cases of pulmonary infection were analyzed, and the incidence was 32.17%. Diabetes (OR 2.302, 95% CI 1.285-3.972), hypoproteinemia (OR 1.992, 95% CI 1.125-3.101), administration of glucocorticoids (OR 2.934, 95% CI 1.412-4.661), ASIA grade A (OR 3.672, 95% CI 1.988-5.046), mechanical ventilation for ≥ 6 days (OR 2.108, 95% CI 1.385-4.751), and length of hospital stay for ≥ 20 days (OR 2.137, 95% CI 1.092-3.842) were risk factors for pulmonary infection in patients with spinal cord injury post-tracheostomy. Among 213 pathogenic bacteria, 52 (51.48%) were Gram-negative and 24 (23.76%) were Gram-positive. Klebsiella pneumoniae (15.84%) and Staphylococcus aureus (8.91%) were the most common pathogenic bacteria. The mortality rate of patients with gram-positive infection was higher than that of patients with gram-negative infection. K. pneumoniae and S. aureus were sensitive to cefoperazone, meropenem, and levofloxacin. Conclusion: Pulmonary infection is a complication post-tracheostomy in patients with spinal cord injury. Diabetes, hypoproteinemia, administration of glucocorticoids, mechanical ventilation for ≥ 6 days, length of hospital stay for ≥ 20 days were risk factors for pulmonary infection. Pulmonary infection was mainly caused by gram-negative bacteria. Timely and effective measures for managing risk factors are essential for improving the prognosis of pulmonary infection post-tracheostomy in patients with spinal cord injuries.

20.
Int J Mol Sci ; 24(19)2023 Sep 24.
Article de Anglais | MEDLINE | ID: mdl-37833946

RÉSUMÉ

Along with the known risk factors of cardiovascular diseases (CVDs) constituting metabolic syndrome (MS), the gut microbiome and some of its metabolites, in particular trimethylamine-N-oxide (TMAO), are actively discussed. A prolonged stay under natural hypoxic conditions significantly and multi-directionally changes the ratio of gut microbiome strains and their metabolites in feces and blood, which is the basis for using hypoxia preconditioning for targeted effects on potential risk factors of CVD. A prospective randomized study included 65 patients (32 females) with MS and optimal medical therapy. Thirty-three patients underwent a course of 15 intermittent hypoxic-hyperoxic exposures (IHHE group). The other 32 patients underwent sham procedures (placebo group). Before and after the IHHE course, patients underwent liver elastometry, biochemical blood tests, and blood and fecal sampling for TMAO analysis (tandem mass spectrometry). No significant dynamics of TMAO were detected in both the IHHE and sham groups. In the subgroup of IHHE patients with baseline TMAO values above the reference (TMAO ≥ 5 µmol/l), there was a significant reduction in TMAO plasma levels. But the degree of reduction in total cholesterol (TCh), low-density lipoprotein (LDL), and regression of liver steatosis index was more pronounced in patients with initially normal TMAO values. Despite significant interindividual variations, in the subgroup of IHHE patients with MS and high baseline TMAO values, there were more significant reductions in cardiometabolic and hepatic indicators of MS than in controls. More research is needed to objectify the prognostic role of TMAO and the possibilities of its correction using hypoxia adaptation techniques.


Sujet(s)
Hyperoxie , Syndrome métabolique X , Femelle , Humains , Facteurs de risque cardiométabolique , Études prospectives , Méthylamines/métabolisme , Facteurs de risque , Hypoxie
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