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The evolution of macromolecular complex is a fundamental biological question, which is related to the origin of life and also guides our practice in synthetic biology. The chemosensory system is one of the complex structures that evolved very early in bacteria and displays enormous diversity and complexity in terms of composition and array structure in modern species. However, how the diversity and complexity of the chemosensory system evolved remains unclear. Here, using the Campylobacterota phylum with a robust "eco-evo" framework, we investigated the co-evolution of the chemosensory system and one of its important signaling outputs, flagellar machinery. Our analyses show that substantial flagellar gene alterations will lead to switch of its primary chemosensory class from one to another, or result in a hybrid of two classes. Unexpectedly, we discovered that the high-torque generating flagellar motor structure of Campylobacter jejuni and Helicobacter pylori likely evolved in the last common ancestor of the Campylobacterota phylum. Later lineages that experienced significant flagellar alterations lost some key components of complex scaffolding structures, thus derived simpler structures than their ancestor. Overall, this study revealed the co-evolutionary path of the chemosensory system and flagellar system, and highlights that the evolution of flagellar structural complexity requires more investigation in the Bacteria domain based on a resolved phylogenetic framework, with no assumptions on the evolutionary direction.
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Campylobacter jejuni , Helicobacter pylori , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Campylobacter jejuni/genética , Flagelos/genética , FilogeniaRESUMO
BACKGROUND & AIMS: The role of solute carrier family 25 member 15 (SLC25A15), a critical component of the urea cycle, in hepatocellular carcinoma (HCC) progression remains poorly understood. This study investigated the impact of SLC25A15 on HCC progression and its mechanisms. METHODS: We systematically investigated the function of SLC25A15 in HCC progression using large-scale data mining and cell, animal, and organoid models. Furthermore, we analyzed its involvement in reprogramming glutamine metabolism. RESULTS: SLC25A15 expression was significantly decreased in HCC tissues, and patients with low SLC25A15 levels had a poorer prognosis. Hypoxia-exposed HCC cells or tissues had lower SLC25A15 expression. A positive correlation between HNF4A, a transcription factor suppressed by hypoxia, and SLC25A15 was observed in both HCC tissues and cells. Modulating HNF4A levels altered SLC25A15 mRNA levels. SLC25A15 upregulated SLC1A5, increasing glutamine uptake. The reactive metabolic pathway of glutamine was increased in SLC25A15-deficient HCC cells, providing energy for HCC progression through additional lipid synthesis. Ammonia accumulation due to low SLC25A15 levels suppressed the expression of OGDHL (oxoglutarate dehydrogenase L), a switch gene that mediates SLC25A15 deficiency-induced reprogramming of glutamine metabolism. SLC25A15-deficient HCC cells were more susceptible to glutamine deprivation and glutaminase inhibitors. Intervening in glutamine metabolism increased SLC25A15-deficient HCC cells' response to anti-PD-L1 treatment. CONCLUSION: SLC25A15 is hypoxia-responsive in HCC, and low SLC25A15 levels result in glutamine reprogramming through SLC1A5 and OGDHL regulation, promoting HCC progression and regulating cell sensitivity to anti-PD-L1. Interrupting the glutamine-derived energy supply is a potential therapeutic strategy for treating SLC25A15-deficient HCC. IMPACT AND IMPLICATIONS: We first demonstrated the tumor suppressor role of solute carrier family 25 member 15 (SLC25A15) in hepatocellular carcinoma (HCC) and showed that its deficiency leads to reprogramming of glutamine metabolism to promote HCC development. SLC25A15 can serve as a potential biomarker to guide the development of precision therapeutic strategies aimed at targeting glutamine deprivation. Furthermore, we highlight that the use of an inhibitor of glutamine utilization can enhance the sensitivity of low SLC25A15 HCC to anti-PD-L1 therapy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Carcinoma Hepatocelular/genética , Glutamina , Neoplasias Hepáticas/genética , Hipóxia/genética , Transporte Biológico , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos/genéticaRESUMO
We report on a high-power and narrow-linewidth nanosecond pulsed intracavity crystalline Raman laser at 1.7â µm. Driven by an acousto-optically Q-switched 1314â nm two-crystal Nd:YLF laser, the highly efficient cascaded YVO4 Raman laser at 1715nm was obtained within the well-designed L-shaped resonator. Thanks to the absence of spatial hole burning in the stimulated Raman scattering process, significant spectral purification of second-Stokes radiation was observed by incorporating a fused silica etalon in the high-Q fundamental cavity. Under the repetition rate of 4 kHz, the highest average output power for single longitudinal mode operation was up to 2.2 W with the aid of precision vibration isolation and precision temperature controlling, corresponding to the pulse duration of â¼2.8â ns and the spectral linewidth of â¼330â MHz. Further increasing the launched pump power, the second-Stokes laser tended toward be always multimode, and the maximum average output power amounted to 4.8 W with the peak power of â¼0.8â MW and the spectral linewidth of â¼0.08â nm. The second-Stokes emission was near diffraction limited with M2 < 1.4 across the whole pump power range.
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We demonstrate the first ten-watt-level eye-safe intracavity crystalline Raman laser, to the best of our knowledge. The efficient high-power eye-safe Raman laser is intracavity-pumped by an acousto-optically Q-switched 1314â nm two-crystal Nd:YLF laser. Benefiting from the unique bi-axial properties of KGW crystal, two sets of eye-safe dual-wavelength Raman lasers operating at 1461, 1645â nm and 1490, 1721nm are achieved by rotating the Raman crystal. Under the launched pump power of 84.9 W and the repetition rate of 4 kHz, the maximum first-Stokes output powers of 7.9 W at 1461â nm and 8.2 W at 1490â nm are acquired with the second-Stokes output powers of 1.4 W at 1645â nm and 1.5 W at 1721nm, respectively, leading to the eye-safe dual-wavelength Raman output powers of up to 9.3 and 9.7 W. Meanwhile, the pulse durations at the wavelengths of 1461, 1490, 1645, 1721nm are determined to be 4.8, 5.5, 4.3, and 3.6â ns, respectively, which give rise to the peak powers approaching about 410, 370, 80, 100â kW. These Stokes emissions are found to be near diffraction limited with M2 < 1.6 across the entire output power range.
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A highly powerful nanosecond pulsed deep-red laser was demonstrated by intracavity second-harmonic generation of an actively Q-switched Nd:YLF dual-crystal-based KGW Raman laser in a critically phase-matched lithium triborate (LBO) crystal. The first-Stokes fields at 1461 and 1490â nm driven by the 1314â nm fundamental laser were firstly produced by accessing the Raman shifts of 768 and 901â cm-1 in the KGW crystal, respectively, and thereafter converted to the deep-red emission lines at 731 and 745â nm by finely tuning the phase-matching angle of the LBO crystal and carefully realigning the resonator. Integrating the benefits of the Nd:YLF dual-crystal configuration and the meticulously designed L-shaped resonator, this deep-red laser system delivered the maximum average output powers of 5.2 and 7.6â W with the optical power conversion efficiencies approaching 6.3% and 9.2% under the optimal pulse repetition frequency of 4â kHz, respectively. The pulse durations of 6.7 and 5.5â ns were acquired with the peak powers up to approximately 190 and 350â kW, respectively, and the resultant beam qualities were determined to be near-diffraction-limited with M2 ≈ 1.5.
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We report on a high average power and high repetition rate nanosecond pulsed eye-safe KGW Raman laser intracavity driven by an acousto-optic Q-switched 1342â nm two-crystal Nd:YVO4 laser. Taking advantages of the carefully selected two-composite-laser-crystal configuration, the thoroughly optimized gate-open time of acousto-optic modulator and the ingeniously designed U-shaped resonator, substantial power and efficiency enhancements as well as superior mode matching have been enabled. Under the injected pump power of 64.5â W, the average output powers of the first-Stokes fields at 1496 and 1527â nm can be up to 8.1 and 9.5â W with 25â kHz repetition rate and 3.2â µs gate-open time, respectively, corresponding to the optical power conversion efficiencies of 12.6% and 14.7%. Meantime, the resultant pulse widths are determined to be 4.6 and 6.3â ns with the peak powers of approximately 70 and 60â kW, respectively. The beam quality can be maintained with M2 < 1.5 across the entire output power range.
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Bacterial colonization and biofilm formation on abiotic surfaces are initiated by the adhesion of peptides and proteins. Understanding the adhesion of such peptides and proteins at a molecular level thus represents an important step toward controlling and suppressing biofilm formation on technological and medical materials. This study investigates the molecular adhesion of a pilus-derived peptide that facilitates biofilm formation of Pseudomonas aeruginosa, a multidrug-resistant opportunistic pathogen frequently encountered in healthcare settings. Single-molecule force spectroscopy (SMFS) was performed on chemically etched ZnO 11 2 â¾ 0 ${\left(11\bar{2}0\right)}$ surfaces to gather insights about peptide adsorption force and its kinetics. Metal-free click chemistry for the fabrication of peptide-terminated SMFS cantilevers was performed on amine-terminated gold cantilevers and verified by X-ray photoelectron spectroscopy (XPS) and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS). Atomic force microscopy (AFM) and XPS analyses reveal stable topographies and surface chemistries of the substrates that are not affected by SMFS. Rupture events described by the worm-like chain model (WLC) up to 600â pN were detected for the non-polar ZnO surfaces. The dissociation barrier energy at zero force ΔG(0), the transition state distance xb and bound-unbound dissociation rate at zero force koff (0) for the single crystalline substrate indicate that coordination and hydrogen bonds dominate the peptide/surface interaction.
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Aderência Bacteriana , Óxido de Zinco , Pseudomonas aeruginosa , Peptídeos , Espectroscopia Fotoeletrônica , Microscopia de Força Atômica , Biofilmes , Propriedades de SuperfícieRESUMO
OBJECTIVE: To estimate the pooled prevalence, as well as the spatial and temporal distribution, of urolithiasis among subjects in China. MATERIALS AND METHODS: We conducted a comprehensive search of both Chinese and English databases to retrieve literature pertaining to the prevalence of urolithiasis in the indigenous Chinese population. A random-effects meta-analysis model was employed to calculate the pooled prevalence of urolithiasis. Subgroup analyses were conducted based on factors such as time, region, gender, and sample size. Prevalence and spatial distribution maps were created based on provinces and latitude/longitude coordinates. RESULTS: A total of 46 studies conducted in 22 provinces across China were included in this meta-analysis and the pooled prevalence of urolithiasis, kidney stones, ureteric calculi, urethral and bladder stones were 8.1% (95% confidence interval [CI] 5.6-11.1%), 7.8% (95% CI 5.8-10.0%), 3.2% (95% CI 0.6-5.7%), 0.5% (95% CI 0.1-0.9%). Most of the urolithiasis prevalence screening in China was concentrated between 100° E and 120° E, with higher rates observed in low latitude areas. Subgroup analysis of kidney stones revealed that Guangdong (12.7%) and Guangxi (10.3%) had the highest prevalence, with the eastern developed area exhibiting higher rates compared to the west. The prevalence in males was higher than in females (odds ratio 1.67, 95% CI 1.46-1.92), although the gender gap has significantly reduced since 2006. Moreover, a greater sample size is associated with a decreased prevalence of urolithiasis. CONCLUSIONS: The prevalence of urolithiasis is increasing in China, and there are noteworthy regional or provincial disparities in occurrence. It is worth noting that the current number of screening studies in some areas is insufficient. Additional investigations with appropriate sample sizes should be supplemented in time.
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Cálculos Renais , Cálculos da Bexiga Urinária , Urolitíase , Masculino , Feminino , Humanos , Prevalência , China/epidemiologia , Urolitíase/epidemiologia , Cálculos Renais/epidemiologiaRESUMO
We demonstrate an efficient wavelength-selectable output in the attractive deep-red spectral region from an intracavity frequency converted Nd:YLF/KGW Raman laser. Driven by an acousto-optic Q-switched 1314â nm Nd:YLF laser, two first-Stokes waves at 1461 and 1490â nm were generated owing to the bi-axial properties of KGW crystal. By incorporating intracavity sum-frequency generation and second-harmonic generation with an angle-tuned bismuth borate (BIBO) crystal, four discrete deep-red laser emission lines were yielded at the wavelengths of 692, 698, 731, and 745â nm. Under the incident pump power of 50 W and the repetition rate of 4 kHz, the maximum average output powers of 2.4, 2.7, 3.3, and 3.6 W were attained with the pulse durations of 3.4, 3.2, 4.3, and 3.7â ns, respectively, corresponding to the peak powers up to 177, 209, 190, and 245â kW. The results indicate that the Nd:YLF/KGW Raman laser combined with an angle-adjusted BIBO crystal provides a reliable and convenient approach to achieve the selectable multi-wavelength deep-red laser with short pulse duration and high peak power.
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High beam quality 588â nm radiation was realized based on a frequency-doubled crystalline Raman laser. The bonding crystal of YVO4/Nd:YVO4/YVO4 was used as the laser gain medium, which can accelerate the thermal diffusion. The intracavity Raman conversion and the second harmonic generation were realized by a YVO4 crystal and an LBO crystal, respectively. Under an incident pump power of 49.2 W and a pulse repetition frequency of 50 kHz, the 588â nm power of 2.85 W was obtained with a pulse duration of 3â ns, corresponding to a diode-to-yellow laser conversion efficiency of 5.75% and a slope efficiency of 7.6%. Meanwhile, a single pulse's pulse energy and peak power were 57 µJ and 19â kW, respectively. The severe thermal effects of the self-Raman structure were overcome in the V-shaped cavity, which has excellent mode matching, and combined with the self-cleaning effect of `Raman scattering, the beam quality factor M2 was effectively improved, which was measured optimally to be Mx 2 = 1.207, and My 2 = 1.200, with the incident pump power being 49.2 W.
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We report on a high-repetition-rate and high-beam-quality all-solid-state nanosecond pulsed deep-red laser source by intracavity second harmonic generation of the actively Q-switched Nd:YVO4/KGW Raman laser. The polarization of the 1342â nm fundamental laser was aligned with the Ng and Nm axes of KGW crystal for accessing the eye-safe Raman lasers at 1496 and 1526â nm, respectively. With the aid of the elaborately designed V-shaped resonator and the composite Nd:YVO4 crystal, excellent mode matching and good thermal diffusion have been confirmed. Under an optimal pulse repetition frequency of 25 kHz, the average output powers of the Raman lasers at 1496 and 1526â nm were measured to be 3.7 and 4.9 W with the superior beam quality factor of M2 = 1.2, respectively. Subsequently, by incorporating a bismuth borate (BIBO) crystal, the deep-red laser source was able to lase separately two different spectral lines at 748 and 763â nm, yielding the maximum average output powers of 2.5 and 3.2 W with the pulse durations of 15.6 and 11.3â ns, respectively. The resulting beam quality was determined to be near-diffraction-limited with M2 = 1.28.
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We demonstrate the first multi-segmented Nd:YLF laser, to the best of our knowledge. The multi-segmented crystal was designed to straightforwardly aim for the minimum thermal stress without sacrificing the overall laser efficiency, with the influence of the pump beam waist position considered in particular. Integrating the enhanced thermo-mechanical resistance of multi-segmented crystal and the alleviated heat load of low quantum defect pumping, this end-pumped 1314â nm Nd:YLF laser system delivered a maximum continuous-wave output power of up to 35.5 W under a pump power of 105 W, corresponding to an optical-to-optical efficiency of 33.8%. Furthermore, by incorporating an acousto-optic modulator, an active Q-switching oscillator was accomplished, yielding a maximum average output power of 22.9 W at a pulse repetition frequency (PRF) of 20 kHz and a largest pulse energy of 13.6 mJ at a PRF of 1 kHz.
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Arsenic (As) is one of the most concerning elements due to its high exposure risks to organisms and ecosystems. The interaction between arsenicals and proteins plays a pivotal role in inducing their biological effects on living systems, e.g., arsenicosis. In this review article, the recent advances in analytical techniques and methods of As-binding proteomes were well summarized and discussed, including chromatographic separation and purification, biotin-streptavidin pull-down probes, in situ imaging using novel fluorescent probes, and protein identification. These analytical technologies could provide a growing body of knowledge regarding the composition, level, and distribution of As-binding proteomes in both cells and biological samples, even at the organellar level. The perspectives on analysis of As-binding proteomes are also proposed, e.g., isolation and identification of minor proteins, in vivo targeted protein degradation (TPD) technologies, and spatial As-binding proteomics. The application and development of sensitive, accurate, and high-throughput methodologies of As-binding proteomics would enable us to address the key molecular mechanisms underlying the adverse health effects of arsenicals.
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Arsênio , Arsenicais , Proteoma , Ecossistema , Arsenicais/química , Biotina/químicaRESUMO
BACKGROUND: Long-term exposure of humans to air pollution is associated with an increasing risk of cardiovascular diseases (CVDs). Astaxanthin (AST), a naturally occurring red carotenoid pigment, was proved to have multiple health benefits. However, whether or not AST also exerts a protective effect on fine particulate matter (PM2.5)-induced cardiomyocyte damage and its underlying mechanisms remain unclear. METHODS: In vitro experiments, the H9C2 cells were subjected to pretreatment with varying concentrations of AST, and then cardiomyocyte injury model induced by PM2.5 was established. The cell viability and the ferroptosis-related proteins expression were measured in different groups. In vivo experiments, the rats were pretreated with different concentrations of AST for 21 days. Subsequently, a rat model of myocardial PM2.5 injury was established by intratracheal instillation every other day for 1 week. The effects of AST on myocardial tissue injury caused by PM2.5 indicating by histological, serum, and protein analyses were examined. RESULTS: AST significantly ameliorated PM2.5-induced myocardial tissue injury, inflammatory cell infiltration, the release of inflammatory factors, and cardiomyocyte H9C2 cell damage. Mechanistically, AST pretreatment increased the expression of SLC7A11, GPX4 and down-regulated the expression of TfR1, FTL and FTH1 in vitro and in vivo. CONCLUSIONS: Our study suggest that ferroptosis plays a significant role in the pathogenesis of cardiomyocyte injury induced by PM2.5. AST may serve as a potential therapeutic agent for mitigating cardiomyocyte injury caused by PM2.5 through the inhibition of ferroptosis.
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Ferroptose , Miócitos Cardíacos , Humanos , Animais , Ratos , Xantofilas/farmacologia , Xantofilas/uso terapêutico , Material Particulado/toxicidadeRESUMO
The coupling of intense laser field and electric field serves as a new method to achieve the desired electronic states, optical absorption coefficients and refractive index changes of cubic quantum dot for the first time, to the best of our knowledge. The stationary Schrödinger equation was derived and calculated by means of the Kramers-Henneberger transformation, the non-perturbative Floquet method, and the finite difference method. The energy-level anticrossing is activated by multi-physical field to transform suitable quantum states, resulting in the multiple-polarization-selective absorption and refractive index changes. The results show that ultra-wideband frequency shift and resonance enhancement characteristics of optical absorption coefficients and refractive index changes strongly depend on the laser-dressed parameter, the amplitude of electric field, and the polarization directions of the intense laser field and electric field.
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A stable, efficient, and powerful 1314 nm Nd:YLF laser inband-pumped by a wavelength-locked narrowband 880 nm laser diode is demonstrated. The influence of mode-to-pump ratio on the performance of the diode-end-pumped Nd:YLF laser has been systematically investigated by taking into account the thermal effect and the energy transfer upconversion effect. For the optimum mode-to-pump ratio of 0.84, the maximum continuous wave output power of 21.9 W was extracted under the pump power of 70 W, which corresponded to the optical power efficiency of 31.3% and the beam quality of M2 ≈ 1.6. The resultant output power stability was determined to be 0.059% (RMS) within 1 h. In addition, by increasing the mode-to-pump ratio to 1.0, the near-diffraction-limited beam (M2 ≈ 1.3) was achieved with the output power of 17.0 W and the optical power efficiency of 24.3%.
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An efficient high-power nanosecond pulsed deep-red laser at 745â nm is produced by intracavity frequency-doubling an acousto-optically Q switched Nd:YLF/KGW Raman laser using a lithium triborate (LBO) crystal. The critically phase-matched type-I LBO crystal with an optimized length of 25 mm is adopted to enable efficient second-harmonic generation and to suppress unwanted cascaded Stokes fields. Under a repetition rate of 4 kHz, the maximum average output power of 4.1 W is obtained with the launched pump power of 50 W, resulting in an overall optical power conversion efficiency of 8.2%. The average beam quality factor is determined to be M2 = 1.46. The pulse energy is scaled up to 3.3 mJ at the repetition rate of 1 kHz, corresponding to a pulse width of 4.2â ns and a peak power of up to 0.8 MW. Moreover, we theoretically investigate the dependence of the conversion efficiency on the walk-off angle as well as the fundamental and first-Stokes losses, which will guide further optimization of experimental devices.
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We demonstrate the first nanosecond pulsed single longitudinal mode (SLM) intracavity-pumped diamond Raman laser, to the best of our knowledge. The eye-safe coherent source at 1634â nm, which was converted from the actively Q-switched 1342â nm Nd:YVO4 laser, yielded 4.35 W of multimode average output power with a pulse duration of 6â ns and peak power of 29â kW. By exploiting the spatial hole burning free gain mechanism in the Raman media, stable SLM operation was observed at low output power (0.46 W) for the free-running case. Furthermore, by incorporating an etalon in the fundamental standing-wave cavity, the spectral linewidth of the fundamental field was suppressed substantially below the diamond Raman gain linewidth and slightly less than the free spectral range of the mm-scale Raman resonator. Thereby, a much higher SLM output power of 1.63 W was obtained with a pulse duration of â¼9â ns and a spectral linewidth of â¼77â MHz.
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Carbon nanotube (CNT)/copper (Cu) composite fibers are placed great expectations as the next generation of light-weight, conductive wires. However, the electrical and mechanical performances still need to be enhanced. Herein, we demonstrate a strategy that is electrodeposition Cu on thiolated CNT fibers to solve the grand challenge which is enhancing the performance of CNT/Cu composite fibers. Thiol groups are introduced to the surface of the CNT fibers through a controllable O2plasma carboxylation process and amide reaction. Compared with CNT/Cu composite fibers, there are 82.7% and 29.6% improvements in electrical conductivity and tensile strength of interface thiol-modification composite fibers. The enhancement mechanism is also explored that thiolated CNT fibers could make strong interactions between Cu and CNT, enhancing the electrical and mechanical performance of CNT/Cu composites. This work proposes a convenient, heat-treatment-free strategy for high-performance CNT/Cu composite fibers, which can be manufactured for large-scale production and applied to next-generation conductive wires.
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Evidence on the health benefits of vitamin C supplementation in highly polluted areas has not been evaluated. We aimed to evaluate whether dietary vitamin C supplementation can improve vascular health linked to particulate matter (PM) exposure. A randomised double-blind crossover trial involving 58 health young adults was performed in Shijiazhuang, China in 2018. All subjects were randomly assigned to the vitamin C supplementation group (2000 mg/d) or placebo group for a week alternating with a 2 week washout period. Fifteen circulating biomarkers were measured. Linear mixed-effect model was applied to evaluate the effect of vitamin C supplementation on health outcomes. The average concentrations of PM2.5 and PM10 were 164.91 and 327.05 µg/m3, respectively. Vitamin C supplementation was significantly associated with a 19.47% decrease in interleukin-6 (IL-6), 17.30% decrease in tumour necrosis factor-a (TNF-α), 34.01% decrease in C-reactive protein (CRP), 3.37% decrease in systolic blood pressure (SBP) and 6.03% decrease in pulse pressure (PP). Furthermore, glutathione peroxidase (GSH-Px) was significantly increased by 7.15%. Sex-subgroup analysis showed that vitamin C significantly reduced TNF-α by 27.85% in male participants and significantly increased APOB by 6.28% and GSH-Px by 14.47% only in female participants. This study indicated that vitamin C supplementation may protect vascular vessels against PM exposure among healthy young adults in China.