Publications by authors named "Hao Hao"

30 Publications

  • Page 1 of 1

Intravenous immunoglobulin-based adjuvant therapy for severe COVID-19: a single-center retrospective cohort study.

Virol J 2021 05 21;18(1):101. Epub 2021 May 21.

Department of Critical Care Medicine, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People's Republic of China.

Objective: Coronavirus disease 2019 (COVID-19) is a major challenge facing the world. Certain guidelines issued by National Health Commission of the People's Repubilic of China recommend intravenous immunoglobulin (IVIG) for adjuvant treatment of COVID-19. However, there is a lack of clinical evidence to support the use of IVIG.

Methods: This single-center retrospective cohort study included all adult patients with laboratory-confirmed severe COVID-19 in the Respiratory and Critical Care Unit of Dabie Mountain Regional Medical Center, China. Patient information, including demographic data, laboratory indicators, the use of glucocorticoids and IVIG, hospital mortality, the application of mechanical ventilation, and the length of hospital stay was collected. The primary outcome was the composite end point, including death and the use of mechanical ventilation. The secondary outcome was the length of hospital stay.

Results: Of the 285 patients with confirmed COVID-19, 113 severely ill patients were included in this study. Compared to the non-IVIG group, more patients in the IVIG group reached the composite end point [12 (25.5%) vs 5 (7.6%), P = 0.008] and had longer hospital stay periods [23.0 (19.0-31.0) vs 16.0 (13.8-22.0), P < 0.001]. After adjusting for confounding factors, differences in primary outcomes between the two groups were not statistically significant (P = 0.167), however, patients in the IVIG group had longer hospital stay periods (P = 0.041).

Conclusion: Adjuvant therapy with IVIG did not improve in-hospital mortality rates or the need for mechanical ventilation in severe COVID-19 patients. Our study does not support the use of immunoglobulin in patients with severe COVID-19 patients.
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http://dx.doi.org/10.1186/s12985-021-01575-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139546PMC
May 2021

Redox-Mediated Reversible Supramolecular Assemblies Driven by Switch and Interplay of Peptide Secondary Structures.

Biomacromolecules 2021 06 7;22(6):2563-2572. Epub 2021 May 7.

CAS Center of Excellence for Nanoscience, Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, Chinese Academy of Sciences, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.

The construction of reversible supramolecular self-assembly remains a significant challenge. Here, we demonstrate the redox-triggered reversible supramolecular self-assembly governed by the "check and balance" of two secondary conformations within a brushlike peptide-selenopolypeptide conjugate. The conjugate constitutes a polypeptide backbone whose side chain contains selenoether functional moieties and double bonds to be readily grafted with β-sheet-prone short-peptide NapFFC. The backbone of the conjugate initially assumes a robust and rigid α-helical conformation, which inhibits the supramolecular assembly of the short peptide in the side chain and yields an overall irregular aggregate morphology under native/reduced conditions. Upon oxidation of the selenoether to more hydrophilic selenoxide, the backbone helix switches to a flexible and disordered conformation, which unleashes the side-chain NapFFC self-assembly into nanofibrils via the adoption of β-sheet conformation. The reversible switch of the supramolecular morphology enables efficient loading and tumor-microenvironment-triggered release of anticancer drugs for cancer treatment with satisfactory efficacy and biocompatibility. The interplay and interaction between two well-defined secondary structures within one scaffold offer tremendous opportunity for the design and construction of functional supramolecular biomaterials.
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http://dx.doi.org/10.1021/acs.biomac.1c00300DOI Listing
June 2021

Microfluidic device coupled with total internal reflection microscopy for in situ observation of precipitation.

Eur Phys J E Soft Matter 2021 Apr 20;44(4):57. Epub 2021 Apr 20.

Department of Chemical and Materials Engineering, University of Alberta, Alberta, T6G 1H9, Canada.

In situ observation of precipitation or phase separation induced by solvent addition is important in studying its dynamics. Combined with optical and fluorescence microscopy, microfluidic devices have been leveraged in studying the phase separation in various materials including biominerals, nanoparticles, and inorganic crystals. However, strong scattering from the subphases in the mixture is problematic for in situ study of phase separation with high temporal and spatial resolution. In this work, we present a quasi-2D microfluidic device combined with total internal reflection microscopy as an approach for in situ observation of phase separation. The quasi-2D microfluidic device comprises of a shallow main channel and a deep side channel. Mixing between a solution in the main channel (solution A) and another solution (solution B) in the side channel is predominantly driven by diffusion due to high fluid resistance from the shallow height of the main channel, which is confirmed using fluorescence microscopy. Moreover, relying on diffusive mixing, we can control the composition of the mixture in the main channel by tuning the composition of solution B. We demonstrate the application of our method for in situ observation of asphaltene precipitation and [Formula: see text]-alanine crystallization.
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http://dx.doi.org/10.1140/epje/s10189-021-00066-1DOI Listing
April 2021

Noise-tolerant single-photon imaging with a superconducting nanowire camera.

Opt Lett 2020 Dec;45(24):6732-6735

The quality of an image is limited to the signal-to-noise ratio of the output from sensors. As the background noise increases much more than the signal, which can be caused by either a huge attenuation of light pulses after a long-haul transmission or a blinding attack with a strong flood illumination, an imaging system stops working properly. Here we built a superconducting single-photon infrared camera of negligible dark counts and 60 ps timing resolution. Combining with an adaptive 3D slicing algorithm that gives each pixel an optimal temporal window to distinguish clustered signal photons from a uniformly distributed background, we successfully reconstructed 3D single-photon images at both a low signal level (∼1 average photon per pixel) and extremely high noise background (background-to-signal ratio = 200 within a period of 50 ns before denoising). Among all detection events, we were able to remove 99.45% of the noise photons while keeping the signal photon loss at 0.74%. This Letter is a direct outcome of quantum-inspired imaging that asks for a co-development of sensors and computational methods. We envision that the proposed methods can increase the working distance of a long-haul imaging system or defend it from blinding attacks.
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http://dx.doi.org/10.1364/OL.394087DOI Listing
December 2020

Distinctive Interfacial Charge Behavior and Versatile Photoresponse Performance in Isotropic/Anisotropic WS/ReS Heterojunctions.

ACS Appl Mater Interfaces 2020 Nov 12;12(47):53475-53483. Epub 2020 Nov 12.

College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, P. R. China.

Van der Waals (vdWs) heterostructures based on in-plane isotropic/anisotropic 2D-layered semiconducting materials have recently received wide attention because of their unique interlayer coupling properties and hold a bright future as building blocks for advanced photodetectors. However, a fundamental understanding of charge behavior inside this kind of heterostructure in the photoexcited state remains elusive. In this work, we carry out a systematic investigation into the photoinduced interfacial charge behavior in type-II WS/ReS vertical heterostructures via polarization-dependent pump-probe microscopy. Benefiting from the distinctive (ultrafast and anisotropic) charge-transfer mechanisms, the photodetector based on the WS/ReS heterojunction displays more superior optoelectronic properties compared to its constituents with diverse functionalities including moderate photoresponsivity, polarization sensitivity, and fast photoresponse speed. Additionally, this device can function as a self-driven photodetector without the external bias. These results of our work tangibly corroborate the intriguing interlayer interaction in in-plane isotropic/anisotropic heterostructures and are expected to shed light on designing balanced-performance multifunctional optoelectrical devices.
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http://dx.doi.org/10.1021/acsami.0c14886DOI Listing
November 2020

Shenmai Injection Upregulates Heme Oxygenase-1 to Confer Protection Against Severe Acute Pancreatitis.

J Surg Res 2020 12 23;256:295-302. Epub 2020 Jul 23.

Department of Emergency Center, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China.

Background: To explore the mechanism of Shenmai injection (SMI) on severe acute pancreatitis (SAP) through heme oxygenase-1 (HO-1) signaling.

Methods: A total of 40 male Sprague-Dawley (SD) rats (220-260 g) were grouped into the following four categories (n = 10): SAP + SMI + Zinc protoporphyrin (ZnPP), SAP + SMI, SAP, and sham surgery groups. ZnPP is a specific inhibitor of HO-1. Four percent of sodium taurocholate (1 mL/kg) was retrogradely injected via the pancreatic duct to induce the SAP model. The SAP group rats received 1.6 mL/kg saline by intravenous injection 30 min after the induction of SAP. The SAP + SMI group rats received 1.6 mL/kg SMI by intravenous injection 30 min after the induction of SAP. The SAP + SMI + ZnPP group rats received an intravenous injection of 1.6 mL/kg SMI and intraperitoneal administration of 30 mg/kg ZnPP 30 min after the SAP induction. Twenty-four hours after the SAP induction, blood samples were collected for the measurement of amylase, lipase, creatinine, myeloperoxidase, interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), and HO-1 level, while tissue specimens were harvested for the determination of HO-1, TNF-α, and IL-10 mRNA level. Meanwhile, histopathological changes in organs (pancreas, lung, and kidney) were stored.

Results: The serum concentration of amylase, lipase, creatinine, and myeloperoxidase was higher in the SAP group than in the SAP + SMI group. Treatment with SMI increased HO-1 and IL-10 level and reduced TNF-α level in serum and tissues compared to the SAP group (P < 0.05). Treatment with SMI abolished the organ-damaging effects of SAP (P < 0.05). Furthermore, suppression of HO-1 expression by ZnPP canceled the aforementioned effects.

Conclusions: SMI confers protection against the SAP-induced systemic inflammatory response and multiple organs damage via HO-1 upregulation.
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http://dx.doi.org/10.1016/j.jss.2020.06.035DOI Listing
December 2020

Association of total bilirubin and indirect bilirubin content with metabolic syndrome among Kazakhs in Xinjiang.

BMC Endocr Disord 2020 Jul 22;20(1):110. Epub 2020 Jul 22.

Department of Public Health, Shihezi University School of Medicine, Shihezi, 832000, Xinjiang, China.

Background: Some studies have shown that a high level of bilirubin is a protective factor against metabolic syndrome (MS), while a high level of transaminase is a risk factor for MS. However, the existing results are inconsistent and few cohort studies have been published.

Methods: Using an ambispective cohort study, 565 Kazakhs from Xinjiang, China were selected as the study subjects. The baseline serum bilirubin and transaminase levels of the subjects were divided into quartiles and the relationship between these values and the incidence of MS was analyzed. The definition of MS was based on the Joint Interim Statement (JIS) diagnostic criteria.

Results: The average follow-up time for the subjects was 5.72 years. The cumulative incidence of MS was 36.11% (204 of the 565 subjects), and the incidence density was 63.10/1000 person-years. Multivariate Cox regression analysis showed that the levels of total bilirubin (TBIL) and indirect bilirubin (IBIL) were negatively correlated with the occurrence of MS, Compared to the lowest quartile level (Q1), the hazard ratios of MS the TBIL levels at the Q2-Q4 quartiles were: 0.47 (0.31-0.71), 0.53 (0.35-0.79), and 0.48 (0.32-0.72), respectively, while IBIL levels at the Q2-Q4 quartiles showed an MS hazard ratio of 0.48 (0.32-0.72), 0.54(0.36-0.81), and 0.52 (0.35-0.77), respectively, all at a 95% confidence level. However, no relationship was found between transaminase levels and the incidence of MS.

Conclusion: Serum TBIL and IBIL levels were negatively correlated with the incidence of MS in a Kazakh population in China.
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http://dx.doi.org/10.1186/s12902-020-00563-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7376964PMC
July 2020

A Superconducting Binary Encoder with Multigate Nanowire Cryotrons.

Nano Lett 2020 May 17;20(5):3553-3559. Epub 2020 Apr 17.

Research Institute of Superconductor Electronics (RISE), School of Electronic Science and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China.

Many classic and quantum devices need to operate at cryogenic temperatures, demanding advanced cryogenic digital electronics for processing the input and output signals on a chip to extend their scalability and performance. Here, we report a superconducting binary encoder with ultralow power dissipation and ultracompact size. We introduce a multigate superconducting nanowire cryotron (nTron) that functions as an 8-input OR gate within a footprint of approximately 0.5 μm. Four cryotrons compose a 4-bit encoder that has a bias margin of 18.9%, an operation speed greater than 250 MHz, an average switching jitter of 75 ps, and a power dissipation of less than 1 μW. We apply this encoder to read out a superconducting-nanowire single-photon detector array whose pixel location is digitized into a 4-bit binary address. The small size of the nanowire combined with the low power dissipation makes nTrons promising for future monolithic integration.
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http://dx.doi.org/10.1021/acs.nanolett.0c00498DOI Listing
May 2020

The interaction mechanism between fludarabine and human serum albumin researched by comprehensive spectroscopic methods and molecular docking technique.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Jun 19;233:118170. Epub 2020 Feb 19.

Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central University for Nationalities, Wuhan 430074, China. Electronic address:

Fludarabine (Flu) is widely used to treat B-cell chronic lymphocytic leukemia. HSA is of the essence to human, especially in blood circulation system. The interaction mechanism between Flu and HSA was studied by comprehensive spectroscopic methods and molecular docking technique. UV-vis and FL spectrum results indicated that Flu bond with HSA, and there was a new complex produced at the binding site I in subdomain IIA. Association constants at 298 K were 1.637 × 10 M and 1.552 × 10 M at 310 K, respectively. The negative enthalpy (ΔH) and positive entropy (ΔS) values for the interaction revealed that the binding behavior was driven by hydrophobic forces and hydrogen bonds. The results obtained from UV, RLS spectra, 3D fluorescence and CD spectrum illustrated that Flu could change the secondary structure of HSA. According to molecule docking result, the binding energy of interaction is -11.15 kcal/mol.
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http://dx.doi.org/10.1016/j.saa.2020.118170DOI Listing
June 2020

Three new secoiridoid glycosides from the flower buds of Lonicera japonica.

Chin J Nat Med 2020 Jan;18(1):70-74

Key laboratory of Natural Pharmaceutical Chemistry, Shandong University of Traditional Chinese Medicine, Jinan 250200, China. Electronic address:

Three new secoiridoid glycosides, named lonijapoglycol A (1), aldosecolohanin C (2) and aldosecolohanin B (3), together with three known ones (4-6), have been isolated from the flower the buds of Lonicera japonica. All the structures were identified by spectroscopic analyses. Lonijapoglycol A (1) expressed significant anti-inflammatory activity to inhibit the release of β-glu-curonidase induced by platelet-activating factor in rat polymorphonuclear leukocytes with an IC value of 3.76 μmol·L.
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http://dx.doi.org/10.1016/S1875-5364(20)30006-6DOI Listing
January 2020

Control of Femtoliter Liquid on a Microlens: A Way to Flexible Dual-Microlens Arrays.

ACS Appl Mater Interfaces 2019 Jul 16;11(30):27386-27393. Epub 2019 Jul 16.

Department of Chemical & Materials Engineering, Faculty of Engineering , University of Alberta , Edmonton , Alberta T6G 1H9 , Canada.

Microlens arrays are key elements for light management in optoelectronic devices. The recent advancement in the wearable intelligent electronics has driven the development of flexible microlenses. In this work, we show a controllable and scalable surface-droplet-based strategy to create unconventional flexible polymer microlens arrays. The technique is underpinned by the morphological transition of femtoliter liquid on the surface of a microlens surrounded by a planar area. We found that the droplet liquid wetted the rim of the microlens first and gradually moved upward to the microlens surface with an increase in the liquid volume. The morphology evolution of the droplet is in good agreement with the predication from our simulations based on the interfacial energy minimization under the condition of the pinned boundary. The shape of the droplet on the microlens is well controlled by the droplet volume, aspect ratio of the microlens, and the interfacial energy of the droplets on the microlens. As a result, the obtained structures of one microlens partially covered by a droplet can be produced in arrays over a large scale, serving as templates for fabricating transparent polymer double microlens arrays for improved light emission from the optoelectronic device.
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http://dx.doi.org/10.1021/acsami.9b06390DOI Listing
July 2019

Ultrafast nonlinear absorption enhancement of monolayer MoS with plasmonic Au nanoantennas.

Opt Lett 2019 Jul;44(13):3198-3201

In this work, we experimentally study the nonlinear absorption enhancement of saturable absorption and two-photon absorption on a hybrid structure comprising a monolayer MoS and Au nanoantennas via femtosecond I-scan measurement. Specifically, a 13-fold increment in the linear absorption coefficient is attained at 1.85 eV, along with an 8-fold enhancement of the two-photon absorption coefficient at 1.65 eV, which is attributed to exciton-plasmon coupling resonance and plasmonic hot electron transfer. The exciton-plasmon coupling effect is characterized by stable photoluminescence experiments. Furthermore, the exciton recombination time is extracted from the pump-probe measurement, whose value in the hybrid structure is shortened from 18.5 ps (pure MoS) to 1.84 ps. Our findings facilitate a new perspective to modulate the nonlinear optical response and to promote the performance of nonlinear photonic devices.
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http://dx.doi.org/10.1364/OL.44.003198DOI Listing
July 2019

Ultrafast exciton transfer in perovskite CsPbBr quantum dots and topological insulator BiSe film heterostructure.

Nanotechnology 2019 Aug 5;30(32):325702. Epub 2019 Apr 5.

College of Advanced Interdisciplinary Studies, National University of Defence Technology, Changsha, Hunan 401173, People's Republic of China.

Recently, topological insulator based heterostructures (HSs) have attracted tremendous research interest, due to their efficient carrier transfer features at the heterointerface induced by metallic surface states. Here, a novel HS comprising 0D perovskite CsPbBr quantum dots (QDs) and 2D material topological insulator BiSe film is proposed and experimentally investigated. Specifically, steady state and time-resolved photoluminescence (PL) measurements are employed, from which a significant quenching behaviour is observed in the HS, with an average quenching factor of 93.2 ± 0.8%. Additionally, time-resolved PL spectroscopy affirms that the carrier transfer efficiency can be up to 92.6 ± 0.2%. Furthermore, the dynamics of carrier transfer within the 0D-2D HS are characterized by utilizing femtosecond broadband transient absorption (TA) spectroscopy, revealing an ultrafast exciton transfer from photoexcited CsPbBr QDs to the BiSe film with a time-scale around 1.1 ± 0.2 ps. An alternative important finding is that the band renormalization is exhibited in CsPbBr QDs of the HS, with the dominant factor being the Coulomb screening effect. This work is expected to provide some fundamental understanding of the ultrafast and efficient carrier transfer mechanism underneath HSs based on topological insulators.
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http://dx.doi.org/10.1088/1361-6528/ab166fDOI Listing
August 2019

Cytotoxicity of CdTe quantum dots with different surface coatings against yeast Saccharomyces cerevisiae.

Ecotoxicol Environ Saf 2019 Jun 7;174:467-474. Epub 2019 Mar 7.

State Key Laboratory of Virology & Key laboratory of Analytical Chemistry for Biology and Medicine (MOE), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, PR China; Key Laboratory of Hubei Province for Coal Conversion and New Carbon Materials, College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, PR China. Electronic address:

Cadmium (Cd)-based QDs are well studied owing to their excellent optical properties. The applications of Cd-based QDs in biomedical filed, however, is hindered by its inherent toxicity. In this study, to overcome the inherent toxicity of heavy metals, CdTe QDs were encapsulated with different shells (NAC, MPA and GSH) to reduce the leakage of Cd from the core. We studied the cytotoxicity of the three kinds of CdTe QDs on S. cerevisiae by spectroscopic, electrochemical, microscopic methods and microcalorimetric technique. Results showed that toxicity of CdTe QDs increased with the augment of QD concentration. According to the values of IC ((GSH-CdTe QDs (15.3 nmol/L) < MPA-CdTe QDs (56.2 nmol/L) < NAC-CdTe QDs (89.8 nmol/L)), the most toxic one is GSH-CdTe QDs, followed by MPA-CdTe QDs, then NAC-CdTe QDs. The coatings have contribution to their toxicity. The three kinds of QDs with the similar shape (sphere) can enter the cell by the clathrin-mediated endocytosis and lead to the different impairments. The mechanism of cytotoxicity is due to the release of Cd leading elevation of intracellular reactive oxygen species (ROS), which damage mitochondria. The clathrin-mediated endocytosis is a significant factor in determining the toxicity of CdTe QDs.
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http://dx.doi.org/10.1016/j.ecoenv.2019.03.013DOI Listing
June 2019

Screening and identification of antagonistic actinomycete LA-5 against Botrytis cinerea.

Ying Yong Sheng Tai Xue Bao 2018 Dec;29(12):4172-4180

Department of Life Science, Yuncheng University, uncheng 044000, Shanxi, China.

In this study, actinomycetes were isolated from rhizosphere soil of tomato by spread plate method, with the pathogen Botrytis cinerea as the target fungus. An actinomycete isolate LA-5 with strong antifungal activity was obtained by confrontation culture and Oxford cup double screening method. According to cultural characteristics, physiological and biochemical properties and 16S rDNA analysis, the strain LA-5 was primarily identified as Streptomyces chungwhensis. The second screening results showed that the fermentation filtrate of LA-5 could substantially inhibit the spore germination and mycelium growth of B. cinerea. Both conidium germination and mycelia growth could be inhibited by 100 times fermentation broth of LA-5, with the inhibiting rate being higher than 50%. Furthermore, the inhibited colony showed white mycelia, with sparse and thin aerial hypha, and the obviously decreased branches. Results from in vitro biocontrol experiment showed that control efficiency of filtrate from LA-5 fermentation liquid on B. cinerea could be up to 83.4%, indicating that the strain was a potential antagonist against tomato gray mold.
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http://dx.doi.org/10.13287/j.1001-9332.201812.034DOI Listing
December 2018

Visualized charge transfer processes in monolayer composition-graded WSSe lateral heterojunctions via ultrafast microscopy mapping.

Opt Express 2018 Jun;26(12):15867-15886

Two-dimensional transitional metal dichalcogenides (TMDCs) based lateral heterojunctions have emerged as appealing and intriguing materials for applications in the next generation flexible nanoelectronics. The construction of depletion region near the in-plane interface brings rich opto-electrical dynamics, which is essential for future applications. Due to the synchronous requirement of spatial and time resolution, the study of lateral heterojunction dynamics remains a challenging issue. Herein, with a home-built spatiotemporal femtosecond transient absorption (TAS) spectroscopy platform, we have investigated the ultrafast photocarrier dynamics of monolayer spatial composition-graded WSSe lateral heterojunctions. At the alloy interface, the charge transfer (CT) processes have been visualized and referred to occur in 1 ps time scale. The mobility difference between electrons and holes results in the space modulation of the interface and a significant broadening of rising edge on the shell region. Moreover, carrier lifetime near the interface is extraordinarily extended by over 3 times from 153 ps to 678 ps. All these results unveil its great potential in designing future low cost logic devices and ultrafast optical applications.
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http://dx.doi.org/10.1364/OE.26.015867DOI Listing
June 2018

Coalescence driven self-organization of growing nanodroplets around a microcap.

Soft Matter 2018 Apr;14(14):2628-2637

Department of Chemical & Materials Engineering, Faculty of Engineering, University of Alberta, Edmonton, Alberta T6G1H9, Canada. and Soft Matter & Interfaces Group, School of Engineering, RMIT University, Melbourne, VIC 3001, Australia and Physics of Fluids Group, Department of Science and Engineering, Mesa+ Institute, J. M. Burgers Centre for Fluid Dynamics and the Max Planck Center Twente for Complex Fluid Dynamics, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands.

The coalescence between growing droplets is important for the surface coverage and spatial arrangements of droplets on surfaces. In this work, total internal reflection fluorescence (TIRF) microscopy is utilized to in situ investigate the formation of nanodroplets around the rim of a polymer microcap, with sub-micron spatial and millisecond temporal resolution. We observe that the coalescence among droplets occurs frequently during their growth by solvent exchange. Our experimental results show that the position of the droplet from two merged droplets is related to the size of the parent droplets. The position of the coalesced droplet and the ratio of parent droplet sizes obey a scaling law, reflecting a coalescence preference based on the size inequality. As a result of droplet coalescence, the angles between the centroids of two neighbouring droplets increase with time, obeying a nearly symmetrical arrangement of droplets at various time intervals. The evolution of the position and number from coalescence of growing droplets is modelled. The mechanism for coalescence driven self-organization of growing droplets is general, applicable to microcaps of different sizes and droplets of different liquids. The understanding from this work may be valuable for positioning nanodroplets by nucleation and growth without using templates.
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http://dx.doi.org/10.1039/C7SM02490HDOI Listing
April 2018

Report - In vitro immune potentials of a water-soluble polysaccharide extract from Dioscorea opposita planted in Henan Province, China.

Pak J Pharm Sci 2017 Jul;30(4):1383-1388

Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin, PR China / Department of Food Science, Northeast Agricultural University, Harbin, PR China.

Dioscorea opposita is an edible and medicinal plant available in many areas of China. This study aimed to assess in vitro immune potentials of a water-soluble polysaccharide extract from D. opposita planted in Henan Province, China. In vitro effects of the extract on three immune cells (macrophages, natural killer cells and splenocytes) from mice and secretion of eight immune-related molecules in macrophages and splenocytes were evaluated. In total, the extract exhibited a dose-dependent manner on these immunological responses. The extract at dose level of 50μg/ml enhanced respective splenocyte proliferation, macrophage phagocytosis, and natural killer cell activity by 150%, 18% and 47%, increased secretion of interleukin-2 and interferon-γ (from 41.4 and 24.6 pg/ml to 48.8 and 91.5 pg/ml, respectively) but decreased secretion of interleukin-4 (from 38.9 to 27.9 pg/ml) in splenocytes. The extract at the same dose level also stimulated inducible nitric oxide synthase and lysozyme in macrophages, and enhanced secretion of interleukin-6, interleukin-1β and tumor necrosis factor-α (from 26.6, 73.4 and 39.6 pg/ml to 60.2, 131.0 and 144.7 pg/ml, respectively). It is concluded that water-soluble polysaccharides from D. opposita have immune potentials to the body, via activating immune cells and regulating the secretion of immune-related molecules.
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July 2017

Effect of Shen-Fu Injection () on Hemodynamics in Early Volume Resuscitation Treated Septic Shock Patients.

Chin J Integr Med 2019 Jan 6;25(1):59-63. Epub 2017 Oct 6.

First Clinical College, Shandong University of Traditional Chinese Medicine, Jinan, 250014, China.

Objective: To investigate the hemodynamic effect of Shen-Fu Injection (, SFI) in early volume resuscitation treated septic shock patients by monitoring pulse indicator continuous cardiac output (PICCO).

Methods: All septic shock patients admitted in the Intensive Care Unit of the Affiliated Hospital of Shandong University of Traditional Chinese Medicine from January 1st, 2014 to December 31th, 2015, were reviewed, and totally 65 were enrolled in this study. They were assigned to SFI group (33 cases) and control group (32 cases). All 65 patients underwent conventional treatment mainly including volume resuscitation, antibiotics and vasoactive drugs therapy. The patients of the SFI group received additional 100 mL of SFI intravenously every 12 h. In all 65 patients, the PICCO arterial catheter and vein catheter were implanted within 1 h after the diagnosis of septic shock. In the course of early volume resuscitation, hemodynamic data of patients were recorded by PICCO monitor at 0, 12, and 24 h after the catheter implantation.

Results: The hemodynamic indices of the two groups showed no significant differences at the beginning of 0 h (P>0.05). At 12 and 24 h, the hemodynamic indices of SFI group were significantly improved in comparison with the control group (P<0.05), including cardiac index (CI), global end diastolic volume index (GEDI), mean arterial pressure (MAP) and heart rate (HR). In addition, there was no significant change of extra-vascular lung water index between the two groups (P>0.05).

Conclusion: SFI significantly improved hemodynamic indices such as CI, GEDI, MAP and HR in early volume resuscitation treated septic shock patients.
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http://dx.doi.org/10.1007/s11655-017-2965-zDOI Listing
January 2019

Inhibitory effect of hesperetin on α-glucosidase: Molecular dynamics simulation integrating inhibition kinetics.

Int J Biol Macromol 2017 Aug 18;101:32-39. Epub 2017 Mar 18.

Zhejiang Provincial Key Laboratory of Applied Enzymology, Yangtze Delta Region Institute of Tsinghua University, Jiaxing 314006, PR China. Electronic address:

The α-glucosidase inhibitor is of interest to researchers due to its association with type-2 diabetes treatment. Hesperetin is a flavonoid with natural antioxidant properties. This paper presents an evaluation on the effects of hesperetin on α-glucosidase via inhibitory kinetics using a Molecular Dynamics (MD) simulation integration method. Due to the antioxidant properties of hesperetin, it reversibly inhibits α-glucosidase in a slope-parabolic mixed-type manner (IC=0.38±0.05mM; K=0.23±0.01mM), accompanied by tertiary structural changes. Based on computational MD and docking simulations, two hesperetin rings interact with several residues near the active site on the α-glucosidase, such as Lys155, Asn241, Glu304, Pro309, Phe311 and Arg312. This study provides insight into the inhibition of α-glucosidase by binding hesperetin onto active site residues and accompanying structural changes. Hesperetin presents as a potential agent for treating α-glucosidase-associated type-2 diabetes based on its α-glucosidase-inhibiting effect and its potential as a natural antioxidant.
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http://dx.doi.org/10.1016/j.ijbiomac.2017.03.072DOI Listing
August 2017

The effect of oxaloacetic acid on tyrosinase activity and structure: Integration of inhibition kinetics with docking simulation.

Int J Biol Macromol 2017 Aug 16;101:59-66. Epub 2017 Mar 16.

Zhejiang Provincial Key Laboratory of Applied Enzymology, Yangtze Delta Region, Institute of Tsinghua University, Jiaxing 314006, PR China. Electronic address:

Oxaloacetic acid (OA) is naturally found in organisms and well known as an intermediate of citric acid cycle producing ATP. We evaluated the effects of OA on tyrosinase activity and structure via integrating methods of enzyme kinetics and computational simulations. OA was found to be a reversible inhibitor of tyrosinase and its induced mechanism was the parabolic non-competitive inhibition type (IC=17.5±0.5mM and K=6.03±1.36mM). Kinetic measurements by real-time interval assay showed that OA induced multi-phasic inactivation process composing with fast (k) and slow (k) phases. Spectrofluorimetry studies showed that OA mainly induced regional changes in the active site of tyrosinase accompanying with hydrophobic disruption at high dose. The computational docking simulations further revealed that OA could interact with several residues near the tyrosinase active site pocket such as HIS61, HIS259, HIS263, and VAL283. Our study provides insight into the mechanism by which energy producing intermediate such as OA inhibit tyrosinase and OA is a potential natural anti-pigmentation agent.
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http://dx.doi.org/10.1016/j.ijbiomac.2017.03.073DOI Listing
August 2017

Hydrogen peroxide (HO) irreversibly inactivates creatine kinase from Pelodiscus sinensis by targeting the active site cysteine.

Int J Biol Macromol 2017 Dec 7;105(Pt 3):1595-1601. Epub 2017 Mar 7.

College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, PR China. Electronic address:

Creatine kinase (EC 2.7.3.2, CK) plays an important role in cellular energy metabolism and homeostasis by catalysing the transfer of phosphate between ATP and creatine phosphate. In this study, we investigated the effects of HO on PSCKM (muscle type creatine kinase from Pelodiscus sinensis) by the integrating method between enzyme kinetics and docking simulations. We found that HO strongly inactivated PSCKM (IC=0.25mM) in a first-order kinetic process, and targeted the active site cysteine directly. A conformational study showed that HO did not induce the tertiary structural changes in PSCKM with no extensive exposure of hydrophobic surfaces. Sequential docking simulations between PSCKM and HO indicated that HO interacts with the ADP binding region of the active site, consistent with experimental results that demonstrated HO-induced inactivation. Our study demonstrates the effect of HO on PSCKM enzymatic function and unfolding, and provides important insight into the changes undergone by this central metabolic enzyme in ectothermic animals in response to the environment.
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http://dx.doi.org/10.1016/j.ijbiomac.2017.03.025DOI Listing
December 2017

Morphological Transformation of Surface Femtodroplets upon Dissolution.

J Phys Chem Lett 2017 Feb 17;8(3):584-590. Epub 2017 Jan 17.

Soft Matter & Interfaces Group, School of Engineering, RMIT University , Melbourne, Victoria 3001, Australia.

Constructing controllable liquid patterns with high resolution and accuracy is of great importance in droplet depositions for a range of applications. Simple surface chemical micropatterns have been popularly used to regulate the shape of liquid droplets and the final structure of deposited materials. In this work, we study the morphological evolution of a dissolving femtoliter droplet pinned on multiple microdomains. On the basis of minimization of interfacial energy, the numerical simulations predict various symmetric droplet profiles in equilibrium at different liquid volumes. However, our experimental results show both symmetric and asymmetric shapes of droplets due to contact line pinning and symmetry breaking during droplet dissolution. Upon slow volume reduction, the deposited microdroplet arrays on one single type of simple surface prepatterns spontaneously morphed into a series of complex regular 3D shapes. The findings in this work offer insights into design and prepararion of the rich and complex morphology of liquid patterns via simple surface premicropatterns.
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http://dx.doi.org/10.1021/acs.jpclett.6b02861DOI Listing
February 2017

Adipose-derived mesenchymal stem cells ameliorate hyperglycemia through regulating hepatic glucose metabolism in type 2 diabetic rats.

Biochem Biophys Res Commun 2017 01 21;483(1):435-441. Epub 2016 Dec 21.

Institute of Basic Medicine Science, College of Life Science, Chinese PLA General Hospital, Beijing 100853, China. Electronic address:

Infusion of mesenchymal stem cells (MSCs) has been identified in the rapid alleviation in hyperglycemia of diabetic individuals, but the mechanism involved has not been adequately explained by these cells' potential role in modulating system insulin sensitivity and islet regeneration. In this study, we demonstrated adipose-derived mesenchymal stem cells (ASCs) produced significantly lower blood glucose via promoting hepatic glycogen synthesis and inhibiting hepatic glucose production within 24 h after infusion in T2DM rats. In vitro, HepG2 cells treated with palmitate (PA) were used as a model of hepatic glucose metabolism disorder to confirm that ASCs stimulates the phosphorylation of hepatic AMP-activated protein kinase (AMPK) to restores hepatic glucose metabolism in type 2 diabetes. In summary, this study indicated that ASCs improve hyperglycemia via regulating hepatic glucose metabolism. Additionally, the effect of ASCs on hepatic glucose metabolism depended on the AMPK signaling pathway. Thus, this is the new research of the molecular mechanisms of MSCs administration to improve glucose metabolism, and it may indicate a new treatment target of MSCs in T2DM.
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http://dx.doi.org/10.1016/j.bbrc.2016.12.125DOI Listing
January 2017

Zone specific fractal dimension of retinal images as predictor of stroke incidence.

ScientificWorldJournal 2014 18;2014:467462. Epub 2014 Nov 18.

Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, 176 Hawkesbury Road, Westmead, NSW 2145, Australia.

Fractal dimensions (FDs) are frequently used for summarizing the complexity of retinal vascular. However, previous techniques on this topic were not zone specific. A new methodology to measure FD of a specific zone in retinal images has been developed and tested as a marker for stroke prediction. Higuchi's fractal dimension was measured in circumferential direction (FDC) with respect to optic disk (OD), in three concentric regions between OD boundary and 1.5 OD diameter from its margin. The significance of its association with future episode of stroke event was tested using the Blue Mountain Eye Study (BMES) database and compared against spectrum fractal dimension (SFD) and box-counting (BC) dimension. Kruskal-Wallis analysis revealed FDC as a better predictor of stroke (H = 5.80, P = 0.016, α = 0.05) compared with SFD (H = 0.51, P = 0.475, α = 0.05) and BC (H = 0.41, P = 0.520, α = 0.05) with overall lower median value for the cases compared to the control group. This work has shown that there is a significant association between zone specific FDC of eye fundus images with future episode of stroke while this difference is not significant when other FD methods are employed.
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http://dx.doi.org/10.1155/2014/467462DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4251072PMC
September 2015

A method for visualization of fine retinal vascular pulsation using nonmydriatic fundus camera synchronized with electrocardiogram.

ISRN Ophthalmol 2013 10;2013:865834. Epub 2013 Mar 10.

Department of Public Health, Faculty of Medicine, Yamagata University, Yamagata 990-9585, Japan.

Pulsatile changes in retinal vascular geometry over the cardiac cycle have clinical implication for diagnosis of ocular and systemic vascular diseases. In this study, we report a Vesselness Mapping of Retinal Image Sequence (VMRS) methodology to visualize the vessel pulsation and quantify the pulsatile motions in the cardiac cycle. Retinal images were recorded in an image sequence corresponding to 8 segments of the cardiac cycle using a nonmydriatic fundus camera (Canon CR45, Canon Inc., Japan) modified with ECG-synchronization. Individual cross-sectional vessel diameters were measured separately and the significance of the variations was tested statistically by repeated measures analysis of variance (ANOVA). The graders observed an improved quality of vessel pulsation on a wide region around the optic disk using the VMRS. Individual cross- sectional vessel diameter measurement after visualization of pulsatile motions resulted in the detection of more significant diameter change for both arterioles (3.3 μm, P = 0.001) and venules (6.6 μm, P < 0.001) compared to individual measurement without visualization of the pulsatile motions (all P values > 0.05), showing an increase of 2.1 μm and 4.7 μm for arterioles and venules, respectively.
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http://dx.doi.org/10.1155/2013/865834DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3914199PMC
February 2014

Does retinal vascular geometry vary with cardiac cycle?

Invest Ophthalmol Vis Sci 2012 Aug 24;53(9):5799-805. Epub 2012 Aug 24.

School of Electrical and Computer Engineering, Royal Melbourne Institute of Technology (RMIT University), Melbourne, Australia.

Purpose: Changes in retinal vascular parameters have been shown to be associated with systemic vascular diseases. In this study, we assessed the physiologic variations in retinal vascular measurements during the cardiac cycle.

Methods: Fundus images were taken using electrocardiogram-synchronized retinal camera at nine distinct cardiac points from 15 healthy volunteers (135 images). Analyses of retinal vessel geometric measures, including retinal vessel caliber (individual and summary), tortuosity, branching angle, length-diameter ratio (LDR), and optimality deviation, were performed using semiautomated computer software. Repeated-measures ANOVAs were used to obtain the means and to estimate the variation of each cardiac point compared with cardiac point 1.

Results: There was a significant variation of the caliber of the individual arteriolar and venular vessels. However, there was no significant variation found for vessel caliber summary, represented by the central retinal arteriolar equivalent (CRAE) and the central retinal venular equivalent (CRVE). There was also no significant variation found for tortuosity and branching angle, and LDR showed none or very little variations at different cardiac points: variations in caliber ranges between 0 and 4.1%, tortuosity 0 and 1.5%, branching angle 0 and 3.5%, and LDR 0 and 2%; all values for variations, P > 0.1; linear trend, P > 0.5; and nonlinear trend, P > 0.8.

Conclusions: This study showed that there were minimal variations in the CRAE, CRVE, tortuosity, and branching angle that are clinically used for two-dimensional measures of retinal vascular geometry during cardiac cycles. However, there was significant variation in the caliber of the individual vessels over the cardiac cycle.
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http://dx.doi.org/10.1167/iovs.11-9326DOI Listing
August 2012

Automatic retinal vessel profiling using multi-step regression method.

Annu Int Conf IEEE Eng Med Biol Soc 2011 ;2011:2606-9

RMIT University, Victoria 3001, Australia.

Caliber of the retinal blood vessel is widely used for risk assessment of cardiovascular diseases. Accurate and automatic caliber measurement requires a precise model to be made for the vessel profile. In this paper, we present a new approach for retinal vessel profiling in which the background noise, uneven illuminations and specular reflections have all been considered. In this method, regression analysis is performed with a series of second-order Gaussians to filter and up-sample the original vessel profile. This is then segmented to identify and represent the vessel edges by two Generalized Gaussian functions. The technique has been applied to retinal images and the results have been verified and compared with the state of the art automatic techniques.
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http://dx.doi.org/10.1109/IEMBS.2011.6090719DOI Listing
June 2012

Retinal vessel diameter measurement using unsupervised linear discriminant analysis.

ISRN Ophthalmol 2012 6;2012:151369. Epub 2012 Nov 6.

School of Electrical and Computer Engineering, RMIT University, 124 Latrobe Street, Melbourne, VIC 3000, Australia.

An automatic vessel diameter measurement technique based on linear discriminant analysis (LDA) has been proposed. After estimating the vessel wall, the vessel cross-section profile is divided into three regions: two corresponding to the background and one to the vessel. The algorithm was tested on more than 5000 cross-sections of retinal vessels from the REVIEW dataset through comparative study with the state-of-the-art techniques. Cross-correlation analyses were performed to determine the degree to which the proposed technique was close to the ground truth. The results indicate that proposed algorithm consistently performed better than most of other techniques and was highly correlated with the manual measurement as the reference diameter. The proposed method does not require any supervision and is suitable for automatic analysis.
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http://dx.doi.org/10.5402/2012/151369DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3912583PMC
February 2014

GC-rich promoter elements maximally confers estrogen-induced transactivation of LRP16 gene through ERalpha/Sp1 interaction in MCF-7 cells.

J Steroid Biochem Mol Biol 2008 Mar 8;109(1-2):47-56. Epub 2007 Dec 8.

Department of Molecular Biology, Institute of Basic Medicine, Chinese PLA General Hospital, 28 Fu Xing Road, Beijing 100853, PR China.

LRP16 gene has been characterized as an estrogen-responsive gene. One 1/2ERE/GC-rich site was previously identified to be indispensable for -676/-214 (region A) fragment within LRP16 regulatory region to confer E2 action. Here, we report that -213/-24 fragment (region B) has higher E2-responsiveness than that of region A in MCF-7 cells, but not in HeLa cells. Deletion and mutation analyses of region B showed that multiple GC-sites are involved in the E2-stimulated response and one 30-bp fragment (-213 to -184 bp) is essential for conferring maximum E2-responsiveness. Results from the cotransfection assays containing Sp1-siRNA revealed that Sp1 is required for the basal transcription activity and E2-responsiveness of both regions A and B. Northern blot analysis demonstrated that inhibition of Sp1 in MCF-7 cells not only decreased the basal expression of LRP16, but markedly impaired its upregulation by E2. Results from gel mobility shift assays exhibited the direct binding of Sp1 protein to the 28-bp fragment (-211 to -184 bp), which was enhanced by the ERalpha titer. Moreover, the functional interaction of ERalpha and Sp1 proteins in the presence of E2 at the GC-rich sites in region B was confirmed by chromatin immunoprecipitation (ChIP) assays. In general, these results demonstrate that GC-rich sites in the proximal promoter of LRP16 gene are sufficient for E2 activation of LRP16 and the -213/-184 fragment containing only one GC site is essential for the maximal induction in MCF-7 cells. We also provide a model for Sp1-dependent regulation of genes by E2 through GC-rich motifs.
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http://dx.doi.org/10.1016/j.jsbmb.2007.12.009DOI Listing
March 2008