Zhiguo Zhang

Harbin Institute of Technology, Charbin, Heilongjiang Sheng, China

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Publications (81)190.24 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Oxygen sensing properties of a luminescent material gadolinium labeled hematoporphyrin monomethyl ether (Gd-HMME) based on filter paper were studied. Photoluminescence of Gd-HMME at 712 nm was confirmed to be phosphorescence by a time-resolved spectroscopic analysis and its dependence on oxygen. Quantum yield of the phosphorescence was determined to be 0.014 in air saturated methanol solution (λexc = 532 nm). A linear range was found from 10% to 100% oxygen concentration in Stern–Volmer plots for Gd-HMME based on filter paper. Fast response time, recovery time (t↓, 0.4 ± 0.2 s; t↑, 1.4 ± 0.2 s) and high photostability were achieved. Our results indicate that Gd-HMME is a promising indicator for optical oxygen sensing.
    Sensors and Actuators B Chemical 01/2015; 206:351–356. · 3.84 Impact Factor
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    ABSTRACT: Ultrasound combined with endogenous protoporphyrin IX derived from 5-aminolevulinic acid (ALA-SDT) is known to induce apoptosis in multiple cancer cells and macrophages. Persistent retention of macrophages in the plaque has been implicated in the pathophysiology and progression of atherosclerosis. Here we investigated the effects of inhibition of voltage-dependent anion channel 1 (VDAC1) on ALA-SDT-induced THP-1 macrophages apoptosis. Cells were pre-treated with VDAC1 inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) disodium salt for 1 h or downregulated VDAC1 expression by small interfering RNA and exposed to ultrasound. Cell viability was assessed by MTT assay, and cell apoptosis along with necrosis was evaluated by Hoechst 33342/propidium iodide staining and flow cytometry. Levels of cytochrome c release was assessed by confocal microscope and Western blot. The levels of full length caspases, caspase activation, and VDAC isoforms were analyzed by Western blot. Intracellular reactive oxygen species generation, mitochondrial membrane permeability, and intracellular Ca(2+) [Ca(2+)]i levels were measured with fluorescent probes. We confirmed that the pharmacological inhibition of VDAC1 by DIDS notably prevented ALA-SDT-induced cell apoptosis in THP-1 macrophages. Additionally, DIDS significantly inhibited intracellular ROS generation and apoptotic biochemical changes such as inner mitochondrial membrane permeabilization, loss of mitochondrial membrane potential, cytochrome c release and activation of caspase-3 and caspase-9. Moreover, ALA-SDT elevated the [Ca(2+)]i levels and it was also notably reduced by DIDS. Furthermore, both of intracellular ROS generation and cell apoptosis were predominately inhibited by Ca(2+) chelating reagent BAPTA-AM. Intriguingly, ALA-treatment markedly augmented VDAC1 protein levels exclusively, and the downregulation of VDAC1 expression by specific siRNA also significantly abolished cell apoptosis. Altogether, these results suggest that VDAC1 plays a crucial role in ALA-SDT-induced THP-1 macrophages apoptosis, and targeting VDAC1 is a potential way regulating macrophages apoptosis, a finding that may be relevant to therapeutic strategies against atherosclerosis.
    APOPTOSIS 10/2014; · 3.95 Impact Factor
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    ABSTRACT: A special core/shell/shell structured NaYF4/ NaYF4:Yb3+,Er3+/ NaYF4 (CSS) nanocrystal was designed to ensure each luminescence center on the emitting shell having the same surroundings, which includes a support core NaYF4 nanoparticle in the center coated by a thin emitting shell NaYF4:Yb3+,Er3+ and another NaYF4 shell with adjustable thickness as the outer shielding shell. Green upconversion fluorescence intensity Ig(d) of CSS nanoparticles shows exponential relationship with the thickness d of the shielding shell. When d decreased to 0, Ig(0) decreased ~356 times as compared with Ig(∞) due to the drastic fluorescence quenching of rare earth luminescence centers from surroundings. Practically, the severe effect of surroundings can be eliminated ~ 90% by coating ~4 nm- thick NaYF4 shielding shell.
    CrystEngComm 09/2014; · 3.88 Impact Factor
  • Optics letters. 08/2014; 39(16):4635-4638.
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    ABSTRACT: Under a 980 nm diode laser excitation, the near-infrared (NIR) emissions from Nd3+:F7/24, F5/24, and F3/24 states in Nd3+/Yb3+ codoped CaWO4 powder were studied at temperatures ranging from 303 to 873 K. As the temperature increased, the NIR luminescence intensity was significantly enhanced and nearly 190-fold enhancement was achieved at 873 K compared with that at 303 K. By using the fluorescence intensity ratio technique, the thermometry behaviors through the NIR emissions were investigated. The results illustrate that the sensitivity and the accuracy achieved here are much higher than temperature sensors based on other rare earth ion doped materials.
    Optics Letters 08/2014; 39(16). · 3.39 Impact Factor
  • Source
    Jia Yu, Qiang Gao, Zhiguo Zhang
    Infrared Sensors, Devices, and Applications IV, SPIE; 08/2014
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    ABSTRACT: A precise method for the measurement of diffuse reflectance by using gas absorption spectroscopy technique with an integrating sphere is demonstrated. A quantitative relationship between the diffuse reflectance and the gas absorption spectrum is formulated, which has been further validated by experiments. The precision of the reflectivity measurement depends on the diameter and port fraction of the integrating sphere as well as gas concentration, and it increases linearly with the magnitude of the reflectivity. A high precision of 0.005% was achieved at the reflectivity of 0.98844(5).
    Sensors and Actuators B Chemical 06/2014; 196:147–150. · 3.84 Impact Factor
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    ABSTRACT: Background: In advanced atherosclerosis, chronic endoplasmic reticulum (ER) stress induces foam cells apoptosis and generates inflammatory reactions. Methods: THP-1 macrophage-derived foam cells (FC) were incubated with 1 mM 5-aminolevulinic acid (ALA). After ALA mediated sonodynamic therapy (ALA-SDT), apoptosis of FC was assayed by Annexin V-PI staining. Intracellular reactive oxygen species (ROS) and mitochondrial membrane potential were detected by staining with CellROX® Green Reagent and jc-1. Pretreatment of FC with N-acetylcysteine (NAC), Z-VAD-FMK or 4-phenylbutyrate (4-PBA), mitochondria apoptotic pathway associated proteins and C/EBP-homologous (CHOP) expressions were assayed by wertern blotting. Results: Burst of apoptosis of FC was observed at 5-hour after ALA-SDT with 6-hour incubation of ALA and 0.4 W/cm(2) ultrasound. After ALA-SDT, intracellular ROS level increased and mitochondrial membrane potential collapsed. Translocations of cytochrome c from mitochondria into cytosol and Bax from cytosol into mitochondria, cleaved caspase 9, cleaved caspase 3, upregulation of CHOP, as well as downregulation of Bcl-2 after ALA-SDT were detected, which could be suppressed by NAC. Activation of mitochondria-caspase pathway could not be inhibited by 4-PBA. Cleaved caspase 9 and caspase 3 as well as apoptosis induced by ALA-SDT could be inhibited by Z-VAD-FMK. Conclusion: The mitochondria-caspase pathway is predominant in the apoptosis of FC induced by ALA-SDT though ER stress participates in. © 2014 S. Karger AG, Basel.
    05/2014; 33(6):1789-1801.
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    ABSTRACT: Photodynamic therapy (PDT) is considered a promising new strategy for liver cancer treatment. Three elements of PDT-optical output power, irradiation time, and photosensitizer concentration-play important roles in promoting cell death. This research aimed to characterize the effects of hematoporphyrin monomethyl ether (HMME)-based PDT on hepatocellular carcinoma cells HepG2 and thus elucidate the relationship between cell death and the three elements mentioned earlier. Furthermore, in this study, we present a parameter that represents the cumulative effects of these elements. The accumulation of HMME in HepG2 cells was observed by fluorescence microscopy. The absorption spectrum of HMME was detected using fluorescence spectral analysis. The viability of the treated cells was determined using the MTT assay, and cell apoptosis was evaluated using flow cytometry. We found that the fluorescence intensity was positively correlated with the incubation time for up to 2 h. The cell growth inhibition rate was significantly high and gradually increased with increasing concentrations of HMME or increasing light intensity, which was calculated as optical output power × irradiation time. Further analysis revealed an e-exponential decay of the cell survival rate to the product of the HMME concentration and the light intensity. We defined the product as parameter B (B = optical output power × irradiation time × HMME concentration). Similarly, the rate of cell apoptosis showed roughly e-exponential growth to parameter B. In conclusion, HMME-mediated PDT can significantly kill HepG2 cells, and the killing effect was related to the cumulative effects of the optical output power, the irradiation time, and the HMME concentration. Therefore, the newly defined parameter B, as a comprehensive physical quantity, may be of great significance for the regulation of light and photosensitizer according to patient-specific conditions in clinical practice.
    Lasers in Medical Science 05/2014; · 2.40 Impact Factor
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    ABSTRACT: Photodynamic therapy for deep-lying lesions needs an appropriate imaging modality, precise evaluation of tissue oxygen and an effective photosensitizer. Gadolinium based metalloporphyrins Gd(III)-HMME is proposed in this study as a potential multifunctional theranostic agent, as photosensitizer, ratiometric oxygen sensor and MRI contrast agent. The time resolved spectroscopy revealed the luminescence peak of Gd(III)-HMME at 710 and 779 nm with a lifetime of 64 μs in oxygen-free methanol to be phosphorescent. This phosphorescence is strongly dependent on dissolved oxygen concentration. Its intensity in oxygen saturated methanol solution is 21% of that in deoxygenated solution. The singlet oxygen quantum yields Φ<sub>Δ</sub> of HMME and Gd(III)-HMME in air saturated methanol solution were determined to be 0.79 and 0.40 respectively using comparative spectra method. These phenomena indicate that the oxygen sensibility and production of singlet oxygen of Gd(III)-HMME can fulfill the requirement of PDT treatment.
    Optics Express 02/2014; 22(3):2414-22. · 3.55 Impact Factor
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    ABSTRACT: To develop a fluorescent bioprobe for high-contrast deep tissue fluorescence imaging, monochromatic 800 nm upconversion emissions based on NaYF4: Yb3+, Tm3+ upconversion nanoparticles are investigated. The ratio of I800 to I470, which is used to describe the monochromaticity, showing exponential growth with the increase of Tm3+ doping concentration in NaYF4: Yb3+, Tm3+ nanoparticles, can reach as high as 757 at 4% Tm3+. At such a doping level, the absolute quantum efficiency can reach 3.9 × 10–3 as measured by a calibrated integrating sphere, which is sufficient for fluorescence imaging. High-contrast fluorescence phantom imaging was obtained by adjusting monochromaticity of 800 nm upconversion emission under the excitation of a 980 nm diode laser.
    The Journal of Physical Chemistry C 01/2014; 118(5):2820–2825. · 4.84 Impact Factor
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    ABSTRACT: A method using modulated continuous wave (CW) visible laser to measure time-resolved fluorescence spectra of trivalent rare-earth ions has been developed. Electro-optic modulator was used to modulate the CW pumping laser with a rise time of 2 μs. CW Nd(3+) lasers were used as examples to present the method. Upconversion dynamic process of Ho(3+) was studied utilizing a 532 nm CW laser. Quantum cutting dynamic process from Tb(3+) to Yb(3+) was analyzed by a 473 nm CW laser. This method can be applied to any CW laser such as He-Ne laser, Ar(+) laser, Kr(+) laser, Ti:sapphire laser, etc.
    The Review of scientific instruments 11/2013; 84(11):113106. · 1.52 Impact Factor
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    ABSTRACT: A simple cubic-shaped cavity with a high-diffuse-reflectivity inner coating as a novel gas detection cell was developed. The effective optical path length (EOPL) was evaluated by comparing the oxygen absorption signal in the cavity and in air based on tunable diode laser absorption spectroscopy. The law for a spherical cavity was applied and modified to a cubic cavity as a function of reflectivity ρ, port fraction f, and the side length. Single-pass average path length of the cubic cavity was 0.723(7) times the side length. EOPL can be modified conveniently by adjusting the parameters of the cavity.
    Applied Physics B 10/2013; · 1.78 Impact Factor
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    ABSTRACT: NaYF<sub>4</sub>:Yb, Er/NaYF<sub>4</sub> core-shell nanocrystals with different thickness shells were synthesized. The correlation between shell thickness and upconversion (UC) luminescence intensity was investigated experimentally and theoretically. We found that the UC fluorescence intensity of the core-shell nanocrystals is enhanced exponentially with shell thickness (d) in the form of (1-0.9 exp(-d/d<sub>0</sub>). For our core-shell nanocrystals, the d<sub>0</sub> was determined as about 5.5 nm, corresponding to an enhancement of about 12 times for the 540 nm emission intensity. The d<sub>0</sub> may be treated as the optimized shell thickness, which represents a balance between the conflict requirements of strong UC fluorescence intensity and small total crystal size for bioapplications.
    Optics Letters 06/2013; 38(12):2101-3. · 3.39 Impact Factor
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    ABSTRACT: A method of integrating sphere effective optical path length (EOPL) evaluation using tunable diode laser absorption spectroscopy for gas detection was demonstrated. Oxygen was used as a sample gas for an 8.38 cm diameter integrating sphere calibration; 393.7 ± 1.3 cm EOPL was obtained from the wavelength modulation spectroscopy with second harmonic calibration by measuring oxygen P11 line at 764 nm, which is in agreement with that of 393 cm by using direct absorption spectroscopy calibration. The EOPL calibration accuracy of this method can reach 0.33 %. It has been justified that the EOPL of an integrating sphere is independent of the incident light intensity.
    Applied Physics B 05/2013; · 1.78 Impact Factor
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    ABSTRACT: Photodynamic antimicrobial chemotherapy (PACT) is proposed as a potential candidate to inactivate pathogens in localized infections due to the rapid evolution of bacterial resistance. The treatment modality utilizes nontoxic agents called photosensitizers and harmless visible light to generate reactive oxygen species which result in microbial cells' killing. Hematoporphyrin monomethyl ether (HMME) as a novel and affordable photosensitizer has been used in treating various clinical diseases for years, but few applications in infection. In this report, we studied the bactericidal effects of the HMME-mediated photodynamic reaction on the pathogenic microbes in supragingival plaque which can lead to many oral infectious diseases such as caries, gingivitis, and so on. Our findings demonstrated that HMME promoted an effective action in bacterial reduction with the application of laser energy. Moreover, the antimicrobial activities were dramatically enhanced as the HMME concentration and exposure time were increased, but reached a plateau when matched the appropriate agent concentration and illumination. It was found that the survival fraction of microorganisms is exponentially dependent on the product of HMME concentration and irradiation time. These promising results suggest the HMME may be an excellently cost-effective photosensitizing agent for mediating PACT in the treatment of supragingival plaque-related diseases. An optimized HMME concentration and irradiation time has been found to achieve the best results under our experimental conditions. The high HMME concentration matching short curative time, or vice versa, can achieve the similar therapeutic effect, which may provide more flexible treatment plans according to specific conditions.
    Applied Microbiology and Biotechnology 04/2013; · 3.81 Impact Factor
  • Wei Xu, Hua Zhao, Zhiguo Zhang, Wenwu Cao
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    ABSTRACT: Under 980 nm diode laser excitation, the near infrared (NIR) emissions originated from the 4F7/2/4S3/2 → 4I9/2 (∼750 nm), 4F5/2/2H9/2 → 4I9/2 (∼803 nm), and 4F3/2 → 4I9/2 (∼863 nm) transitions of Nd3+ ions in Nd3+/Yb3+ codoped oxyfluoride glass ceramic were obtained and studied as a function of temperature in the range of 303–623 K. It was observed that these NIR emissions were greatly enhanced with the increase of temperature. An explanation based on the luminescence decay curves was given, and it was found that the thermally enhanced phonon-assisted energy transfer (ET) from Yb3+ to Nd3+ played an important role in such phenomenon. In addition, by using the fluorescence intensity ratio technique, the optical thermometry behavior based on the NIR emissions of Nd3+ ions was investigated. Using the 750 and 863 nm emissions from the Nd3+/Yb3+ codoped glass ceramic, higher sensitivity for temperature measurement can be achieved compared to the previous reported rare earth ions fluorescence based optical temperature sensors. Due to its thermally enhanced NIR emissions, the Nd3+/Yb3+ codoped oxyfluoride glass ceramic is a promising candidate for optical temperature sensors with high sensitivity and good accuracy.
    Sensors and Actuators B Chemical 03/2013; 178:520–524. · 3.84 Impact Factor
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    ABSTRACT: The upconversion quantum efficiency and power-conversion efficiency in Tb3+-Yb3+ codoped glass have been investigated theoretically by the cooperative sensitization rate equation model. Both efficiencies exhibited linear relations with pump-power density and decreased with Yb3+ concentration. It was found that the ratio of quantum efficiency to power-conversion efficiency is constant (0.56) and independent of pump-power density and Yb3+ concentration. The theoretical predictions were confirmed by the experimental results measured by an integrating sphere system. The absolute upconversion efficiency was estimated to be on the order of 10−4 in the pump-power density range of 40–96 W/cm2.
    Journal of the Optical Society of America B 02/2013; 30(2):456-. · 2.21 Impact Factor
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    ABSTRACT: Inflammatory cells exhibit an elevated level of protoporphyrin IX (PpIX) after the administration of 5-aminolevulinic acid (ALA). Here, we investigate the sonodynamic effects of ALA-derived PpIX (ALA-PpIX) on macrophages, which are the pivotal inflammatory cells in atherosclerosis. Cultured THP-1 macrophages were incubated with ALA. Fluorescence microscope and fluorescence spectrometer detection showed that intracellular PpIX increased with the concentration of ALA in the incubation solution in a time dependent manner; the highest level of intracellular PpIX was observed after 3-hour incubation. 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assays demonstrated that lower concentrations (less than 2 mM) of ALA have no influence on cell viability (more than 90% of cells survived), but sonodynamic therapy (SDT) with a low concentration of ALA significantly decreased the survival rate of cells, and the effect was increased with both ALA concentration and ultrasound exposure time. Cell apoptosis and necrosis induced by ALA-mediated SDT (ALA-SDT) were measured using Hoechst 33258 and propidium iodide assay. ALA-SDT induced both cell apoptosis and necrosis, and the maximum apoptosis/necrosis ratio was observed at 6 hours after SDT with 1 mM of ALA and 5 minutes of ultrasound exposure. Flow cytometry analysis showed that ALA-SDT significantly increased late stage apoptotic cells (about 10-fold control). Furthermore, ALA-SDT induced reactive oxygen species generation in THP-1 macrophages immediately after the treatment and a conspicuous loss of mitochondrial membrane potential (MMP) at 6 hours compared with that of the control, ALA alone, and ultrasound alone groups. ALA-SDT exhibited synergistic apoptotic effects on THP-1 macrophages, involving excessive intracellular reactive oxygen species generation and MMP loss. Therefore, ALA-SDT is a potential treatment for atherosclerosis.
    International Journal of Nanomedicine 01/2013; 8:669-76. · 4.20 Impact Factor
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    ABSTRACT: Curcumin is extracted from the rhizomes of the traditional Chinese herb Curcuma longa and has been proposed to function as a photosensitizer. The potential use of curcumin as a sonosensitizer for sonodynamic therapy (SDT) requires further exploration. This study investigated the sonodynamic effect of curcumin on macrophages, the pivotal inflammatory cells in atherosclerotic plaque. THP-1-derived macrophages were incubated with curcumin at a concentration of 40.7 μ mol/L for 2 h and then exposed to pulse ultrasound irradiation (2 W/cm(2) with 0.86 MHz) for 5-15 min. Six hours later, cell viability was decreased in cells that had been treated with ultrasound for 10 and 15 min. After ultrasound irradiation for 15 min, the ratio of apoptotic and necrotic cells in SDT group was higher than that in ultrasound group, and the ratio of apoptotic cells was higher than that of necrotic cells. Both loss of mitochondrial membrane potential and morphological changes of cytoskeleton were apparent 2 h after treatment with curcumin SDT. These findings support that curcumin had sonodynamic effect on THP-1-derived macrophages and that curcumin SDT could be a promising treatment for atherosclerosis.
    BioMed research international. 01/2013; 2013:737264.

Publication Stats

273 Citations
190.24 Total Impact Points

Institutions

  • 2006–2014
    • Harbin Institute of Technology
      • • Institute of Condensed Matter Science and Technology
      • • Department of Physics
      Charbin, Heilongjiang Sheng, China
    • Harbin Normal University
      Charbin, Heilongjiang Sheng, China
  • 2009–2013
    • Harbin Medical University
      • • Department of Cardiology
      • • Department of Pathophysiology
      Harbin, Heilongjiang Sheng, China