Publications by authors named "Hanlin Peng"

12 Publications

  • Page 1 of 1

Compensatory role of endogenous sulfur dioxide in nitric oxide deficiency-induced hypertension.

Redox Biol 2021 Nov 18;48:102192. Epub 2021 Nov 18.

Department of Pediatrics, Peking University First Hospital, Beijing, China. Electronic address:

Objective: This study aimed to determine the communicational pattern of gaseous signaling molecules sulfur dioxide (SO) and nitric oxide (NO) between vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs), and elucidate the compensatory role and significance of endogenous SO in the development of hypertension due to NO deficiency.

Approach And Results: Blood pressure was monitored by the tail-cuff and implantable physiological signal telemetry in L-nitro-arginine methyl ester (l-NAME)-induced hypertensive mice, and structural alterations of mouse aortic vessels were detected by the elastic fiber staining method. l-NAME-treated mice showed decreased plasma NO levels, increased SO levels, vascular remodeling, and increased blood pressure, and application of l-aspartate-β-hydroxamate, which inhibits SO production, further aggravated vascular structural remodeling and increased blood pressure. Moreover, in a co-culture system of HAECs and HASMCs, NO from HAECs did not influence aspartate aminotransferase (AAT)1 protein expression but decreased AAT1 activity in HASMCs, thereby resulting in the inhibition of endogenous SO production. Furthermore, NO promoted S-nitrosylation of AAT1 protein in HASMCs and purified AAT1 protein. Liquid chromatography with tandem mass spectrometry showed that the Cys192 site of AAT1 purified protein was modified by S-nitrosylation. In contrast, dithiothreitol or C192S mutations in HASMCs blocked NO-induced AAT1 S-nitrosylation and restored AAT1 enzyme activity.

Conclusion: Endothelium-derived NO inhibits AAT activity by nitrosylating AAT1 at the Cys192 site and reduces SO production in HASMCs. Our findings suggest that SO acts as a compensatory defense system to antagonize vascular structural remodeling and hypertension when the endogenous NO pathway is disturbed.
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http://dx.doi.org/10.1016/j.redox.2021.102192DOI Listing
November 2021

Endogenous SO Controls Cell Apoptosis: The State-of-the-Art.

Front Cell Dev Biol 2021 7;9:729728. Epub 2021 Oct 7.

Department of Pediatrics, Peking University First Hospital, Beijing, China.

SO, previously known as the product of industrial waste, has recently been proven to be a novel gasotransmitter in the cardiovascular system. It is endogenously produced from the metabolism pathway of sulfur-containing amino acids in mammalians. Endogenous SO acts as an important controller in the regulation of many biological processes including cardiovascular physiological and pathophysiological events. Recently, the studies on the regulatory effect of endogenous SO on cell apoptosis and its pathophysiological significance have attracted great attention. Endogenous SO can regulate the apoptosis of vascular smooth muscle cells, endothelial cells, cardiomyocytes, neuron, alveolar macrophages, polymorphonuclear neutrophils and retinal photoreceptor cells, which might be involved in the pathogenesis of hypertension, pulmonary hypertension, myocardial injury, brain injury, acute lung injury, and retinal disease. Therefore, in the present study, we described the current findings on how endogenous SO is generated and metabolized, and we summarized its regulatory effects on cell apoptosis, underlying mechanisms, and pathophysiological relevance.
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http://dx.doi.org/10.3389/fcell.2021.729728DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8529009PMC
October 2021

Changes in prevalence of nosocomial infection pre- and post-COVID-19 pandemic from a tertiary Hospital in China.

BMC Infect Dis 2021 Jul 20;21(1):693. Epub 2021 Jul 20.

Intensive Care Unit, Children Hospital of Soochow University, Suzhou, Jiangsu, China.

Background: Nosocomial infections (NIs) are an important cause of mortality, and increasing evidence reveals that the prevalence of NIs can be reduced through effective prevention and control measures. The aim of this study was to investigate the impact of the prevention and control measures for the COVID-19 pandemic on NIs.

Methods: A retrospective study was conducted to analyze the prevalence of NIs before and after COVID-19 pandemic for 6 months in the Children's Hospital of Soochow University.

Results: A total of 39,914 patients in 2019 and 34,645 patients in 2020 were admitted to the hospital during the study. There were 1.39% (481/34645) of patients with NIs in 2020, which was significantly lower than the 2.56% (1021/39914) of patients in 2019. The rate of critical and fatal cases was also decreased. In addition, the rate of appropriate handwashing, the number of protective gloves and aprons used per person and the number of healthcare staff per patients were significantly increased. Except for the ICU, the prevalence of nosocomial infection in most departments decreased from 2019 to 2020. Regarding the source of infections, a significant reduction was mainly observed in respiratory (0.99% vs 0.42%, p = 0.000) and digestive tract (0.63% vs 0.14%, p = 0.000). The microorganism analysis of respiratory infections indicated an obvious decline in acinetobacters and fungi. The most significant decline of pathogens in gastrointestinal infections was observed for rotavirus. The comparison of catheter-related nosocomial infections between 2019 and 2020 did not show significant differences.

Conclusions: The prevention and control measures for the COVID-19 pandemic have reduced the nosocomial infection in almost all departments, except the ICU, mainly regarding respiratory, gastrointestinal, and oral infections, while catheter-related infections did not show any differences.
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http://dx.doi.org/10.1186/s12879-021-06396-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8289622PMC
July 2021

Nano-Mechanical Properties and Creep Behavior of Ti6Al4V Fabricated by Powder Bed Fusion Electron Beam Additive Manufacturing.

Materials (Basel) 2021 Jun 1;14(11). Epub 2021 Jun 1.

School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China.

Effects of scanning strategy during powder bed fusion electron beam additive manufacturing (PBF-EB AM) on microstructure, nano-mechanical properties, and creep behavior of Ti6Al4V alloys were compared. Results show that PBF-EB AM Ti6Al4V alloy with linear scanning without rotation strategy was composed of 96.9% α-Ti and 2.7% β-Ti, and has a nanoindentation range of 4.11-6.31 GPa with the strain rate ranging from 0.001 to 1 s, and possesses a strain-rate sensitivity exponent of 0.053 ± 0.014. While PBF-EB AM Ti6Al4V alloy with linear and 90° rotate scanning strategy was composed of 98.1% α-Ti and 1.9% β-Ti and has a nanoindentation range of 3.98-5.52 GPa with the strain rate ranging from 0.001 to 1 s, and possesses a strain-rate sensitivity exponent of 0.047 ± 0.009. The nanohardness increased with increasing strain rate, and creep displacement increased with the increasing maximum holding loads. The creep behavior was mainly dominated by dislocation motion during deformation induced by the indenter. The PBF-EB AM Ti6Al4V alloy with only the linear scanning strategy has a higher nanohardness and better creep resistance properties than the alloy with linear scanning and 90° rotation strategy. These results could contribute to understanding the creep behavior of Ti6Al4V alloy and are significant for PBF-EB AM of Ti6Al4V and other alloys.
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http://dx.doi.org/10.3390/ma14113004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8199181PMC
June 2021

Metabolic Reprogramming of Vascular Endothelial Cells: Basic Research and Clinical Applications.

Front Cell Dev Biol 2021 18;9:626047. Epub 2021 Feb 18.

Department of Pediatrics, Peking University First Hospital, Beijing, China.

Vascular endothelial cells (VECs) build a barrier separating the blood from the vascular wall. The vascular endothelium is the largest endocrine organ, and is well-known for its crucial role in the regulation of vascular function. The initial response to endothelial cell injury can lead to the activation of VECs. However, excessive activation leads to metabolic pathway disruption, VEC dysfunction, and angiogenesis. The pathways related to VEC metabolic reprogramming recently have been considered as key modulators of VEC function in processes such as angiogenesis, inflammation, and barrier maintenance. In this review, we focus on the changes of VEC metabolism under physiological and pathophysiological conditions.
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http://dx.doi.org/10.3389/fcell.2021.626047DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7930387PMC
February 2021

Power controllable gain switched fiber laser at ~ 3 μm and ~ 2.1 μm.

Sci Rep 2021 Jan 13;11(1):1003. Epub 2021 Jan 13.

State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054, China.

Based on a hybrid pumping method consisting of a 1150 nm continuous-wave pump source and a 1950 nm pulsed pump source, we demonstrate a power controllable gain-switched fiber laser in dual wavebands at ~ 3 μm and ~ 2.1 μm. Different pumping schemes for pumping a Ho-doped ZBLAN fiber are studied. Using only the 1950 nm pulsed pump source, ~ 2.1 μm gain-switched pulses with single and double pulses are obtained separately at different pump powers. This phenomenon indicates that the 1950 nm pulsed pump source acts as a modulator to trigger different states of the ~ 2.1 μm pulses. Moreover, by fixing the 1150 nm pump power at 3.259 W and adjusting the 1950 nm pump power, the output power of the ~ 2.1 μm gain-switched pulsed laser is flexibly controlled while the ~ 3 μm laser power is almost unchanged, inducing the maximum output powers of 167.96 mW and 260.27 mW at 2910.16 nm and 2061.65 nm, respectively. These results suggest that the comparatively low power of the ~ 2.1 μm gain-switched pulsed laser in dual-waveband laser can be efficiently overcome by reasonably controlling the 1950 nm pump power.
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http://dx.doi.org/10.1038/s41598-020-80238-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7807083PMC
January 2021

Post-translational Modifications of IκBα: The State of the Art.

Front Cell Dev Biol 2020 5;8:574706. Epub 2020 Nov 5.

Department of Pediatrics, Peking University First Hospital, Beijing, China.

The nuclear factor-kappa B (NF-κB) signaling pathway regulates a variety of biological functions in the body, and its abnormal activation contributes to the pathogenesis of many diseases, such as cardiovascular and respiratory diseases and cancers. Therefore, to ensure physiological homeostasis of body systems, this pathway is strictly regulated by IκBα transcription, IκBα synthesis, and the IκBα-dependent nuclear transport of NF-κB. Particularly, the post-translational modifications of IκBα including phosphorylation, ubiquitination, SUMOylation, glutathionylation and hydroxylation are crucial in the abovementioned regulatory process. Because of the importance of the NF-κB pathway in maintaining body homeostasis, understanding the post-translational modifications of IκBα can not only provide deeper insights into the regulation of NF-κB pathway but also contribute to the development of new drug targets and biomarkers for the diseases.
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http://dx.doi.org/10.3389/fcell.2020.574706DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7674170PMC
November 2020

Negative auto-regulation of sulfur dioxide generation in vascular endothelial cells: AAT1 S-sulfenylation.

Biochem Biophys Res Commun 2020 Feb 19. Epub 2020 Feb 19.

Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China. Electronic address:

Recently, endogenous sulfur dioxide (SO) has been found to exert an important function in the cardiovascular system. However, the regulatory mechanism for SO generation has not been entirely clarified. Hence, we aimed to explore the possible auto-regulation of endogenous SO generation and its mechanisms in vascular endothelial cells. We showed that SO did not affect the protein expression of aspartate aminotransferase 1 (AAT1), a major SO synthesis enzyme, but significantly inhibited AAT activity in primary human umbilical vein endothelial cells (HUVECs) and porcine purified AAT1 protein. An AAT1 enzymatic kinetic study showed that SO reduced the Vmax (1.89 ± 0.10 vs 2.55 ± 0.12, μmol/mg/min, P < 0.05) and increased the Km (35.97 ± 9.54 vs 19.33 ± 1.76 μmol/L, P < 0.05) values. Furthermore, SO induced S-sulfenylation of AAT1 in primary HUVECs and purified AAT1 protein. LC-MS/MS analysis indicated that SO sulfenylated AAT1 at Cys192. Mechanistically, thiol reductant DTT treatment or C192S mutation prevented SO-induced AAT1 sulfenylation and the subsequent inhibition of AAT activity in purified AAT1 protein and primary HUVECs. Our findings reveal, for the first time, a mechanism of auto-regulation of SO generation through sulfenylation of AAT1 at Cys192 to suppress AAT activity in vascular endothelial cells. These findings will greatly deepen the understanding of regulatory mechanisms in the cardiovascular homeostasis.
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http://dx.doi.org/10.1016/j.bbrc.2020.02.040DOI Listing
February 2020

Large aspect ratio gold nanorods (LAR-GNRs) for mid-infrared pulse generation with a tunable wavelength near 3 μm.

Opt Express 2019 Feb;27(4):4886-4896

We report a tunable passively Q-switched fiber laser at the wavelengths near 3 μm, using large aspect ratio gold nanorods (LAR-GNRs) as a saturable absorber (SA) for the first time. The GNRs with a large average aspect ratio of up to ~20 were prepared using the seed-mediated growth method, which yielded a strong absorption band of 2.2-3 μm with a peak at ~2600 nm, stemming from longitudinal surface plasmon resonance (SPR). The corresponding nonlinear absorption was characterized using 2.87 μm ultrafast pulses, giving the modulation depth of 8.89%, saturation intensity of 14.9 MW/cm, and nonsaturation loss of 39.9%. When introducing the material into a tunable Ho/Pr codoped ZBLAN fiber laser as a SA, stable Q-switched pulses with a tunable wavelength within 2.83-2.88 μm were achieved. The largest output power of 30.8 mW, repetition rate of 78.12 kHz, and narrowest pulse width of 2.18 μs were simultaneously attained when tuned to ~2.865 μm at the pump power of 307.2 mW, while the largest pulse energy of 0.48 μJ was obtained at the longest tuning edge of 2.88 μm. Our work indicates that LAR-GNRs are a type of versatile broadband SA material available for the mid-infrared region.
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http://dx.doi.org/10.1364/OE.27.004886DOI Listing
February 2019

Watt-level gain-switched fiber laser at 3.46 μm.

Opt Express 2019 Jan;27(2):1367-1375

We demonstrate a gain-switched fiber laser, yielding a maximum average power of 1.04 W at 3.46 μm, which is the current record of a pulsed rare-earth-doped fiber laser at the wavelength beyond 3 μm, to our knowledge. The corresponding pulse energy is 10.4 μJ with a repetition rate of 100 kHz. A dual-wavelength pumping scheme consisting of a home-made 1950 nm passively Q-switched fiber laser system with a μs-scale pulse width. A 976 nm continuous wave laser diode was used to gain-switch a double-cladding Er-doped ZBLAN fiber laser cavity. Possible laser-quenching behavior during a single-pump pulse was circumvented for the moderate pump peak power and relatively large-pump pulse width. Synchronous gain-switched pulses were achieved with a tunable repetition rate at a wide range of 55~120 kHz, which is the highest gain-switching repetition rate at this band and only limited by our pulsed-pump source. Moreover, the significance of pump pulse width for repetition rate improvement is also discussed. These results provide an available way to produce high-power pulses at the mid-infrared range of 3~5 μm.
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http://dx.doi.org/10.1364/OE.27.001367DOI Listing
January 2019

Microstructure and Properties of Porous High-N Ni-Free Austenitic Stainless Steel Fabricated by Powder Metallurgical Route.

Materials (Basel) 2018 Jun 22;11(7). Epub 2018 Jun 22.

National Engineering Research Center of Near-Net-Shape Forming Technology for Metallic Materials, South China University of Technology, Guangzhou 510640, China.

Porous high-N Ni-free austenitic stainless steel was fabricated by a powder metallurgical route. The microstructure and properties of the prepared porous austenitic stainless steel were studied. Results reveal that the duplex stainless steel transforms into austenitic stainless steel after nitridation sintering for 2 h. The prepared high-N stainless steel consists of γ-Fe matrix and FCC structured CrN. Worm-shaped and granular-shaped CrN precipitates were observed in the prepared materials. The orientation relationship between CrN and austenite matrix is [011]//[011] and (-1-11)//(1-11). Results show that the as-fabricated porous high-nitrogen austenitic stainless steel features a higher mechanical property than common stainless steel foam. Both compressive strength and Young’s modulus decrease with an increase in porosity. The 3D morphology of the prepared porous materials presents good pore connectivity. The prepared porous high-N Ni-free austenitic stainless steel has superior pore connectivity, a good combination of compressive strength and ductility, and low elastic modulus, which makes this porous high-N Ni-free austenitic stainless steel very attractive for metal foam applications.
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http://dx.doi.org/10.3390/ma11071058DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6073529PMC
June 2018
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