Macrophages are excellent imaging targets for detecting atherosclerotic plaques as they are invol... more Macrophages are excellent imaging targets for detecting atherosclerotic plaques as they are involved in all the developmental stages of atherosclerosis. However, no imaging technique is currently capable of visualizing macrophages inside blood vessel walls. The current study develops an intravascular ultrasonic-photoacoustic (IVUP) imaging system combined with indocyanine green (ICG) as a contrast agent to provide morphological and compositional information about the targeted samples. Both tissue-mimicking vessel phantoms and atherosclerotic plaque-mimicking porcine arterial tissues are used to demonstrate the feasibility of mapping macrophages labeled with ICG by endoscopically applying the proposed hybrid technique. A delay pulse triggering technique is able to sequentially acquire photoacoustic (PA) and ultrasound (US) signals from a single scan without using any external devices. The acquired PA and US signals are used to reconstruct 2D cross-sectional and 3D volumetric images of the entire tissue with the ICG-loaded macrophages injected. Due to high imaging contrast and sensitivity, the IVUP imaging vividly reveals structural information and detects the spatial distribution of the ICG-labeled macrophages inside the samples. ICG-assisted IVUP imaging can be a feasible imaging modality for the endoscopic detection of atherosclerotic plaques.
Abstract Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to thei... more Abstract Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to their high theoretical capacities, diverse functionalities, and environmental compatibility. Understanding the working mechanism of organic electrodes is vital to strategic materials design. However, due to lack of suitable characterization tools, it has been challenging to probe the reaction processes of organic electrodes in real-time. Here, non-destructive in situ electron paramagnetic resonance (EPR) was performed on a model organic electrode, 7,7,8,8-tetracyanoquinodimethane (TCNQ) used in rechargeable lithium-ion batteries, to directly follow the redox reactions in real-time. In order to minimize interfering signals from other parts of the batteries than the TCNQ electrode of interest, two sets of batteries are fabricated and studied with in situ EPR: (1) a LiCoO2//Li4Ti5O12 full-cell battery to determine the EPR signal evolution of additives and electrolytes; (2) a LiCoO2//TCNQ battery, and the difference in the observed EPR signals reflects purely the redox reactions of TCNQ upon lithiation and delithiation. A two-electron reversible redox reaction is delineated for TCNQ. TCNQ dimers form during the first electron injection upon lithiation and followed by the break-down of the dimers and associated electron coupling to produce massive delocalized electrons, resulting in increased EPR signal during the 2nd electron injection. Reversible trends are observed during electron ejection upon delithiation. In situ EPR is very sensitive to electron activities, thus is a powerful tool to follow redox reactions of organic electrodes, allowing for improved fundamental understanding of how organic electrodes work and for informed design of high-performance organic materials for energy storage.
This study synthesized cellulose-g-poly(acrylic acid) with high water absorbency using the cellul... more This study synthesized cellulose-g-poly(acrylic acid) with high water absorbency using the cellulose extracted from pineapple leaves. The synthesis experiment used a novel combination of ethylene glycol dimethacrylate (EGDMA) and azobisisobutyronitrile (AIBN) as the cross-linker and the initiator, respectively. Experimental results showed that the concentrations of AIBN and EGDMA had significant effects on the structure and the water absorbency of the cross-linked materials. The cellulose-g-poly(acrylic acid) synthesized with 0.5 wt% AIBN and 0.5 wt% EGDMA had an excellent swelling capacity of 1900 g/g in distilled water, significantly larger than previously reported ones. Compared with poly(acrylic acid), the cross-linked product demonstrated an absorbency improvement of 1.65 times in distilled water and 1.27 times in 8.6 ppm NaCl solution that was the highest salinity level in Ben Tre, Vietnam, in March 2020. Therefore, the obtained product showed high potential for agricultural applications, especially in coastal regions facing a growing thread of saltwater intrusion.
Journal of Advanced Biotechnology and Experimental Therapeutics
Ovarian cancer is one of the most popular causes of mortality among women, and the prevalence of ... more Ovarian cancer is one of the most popular causes of mortality among women, and the prevalence of ovarian cancer is increased. Early diagnosis of this disease via genetic variant testing is one potential strategy for enhancing treatment and disease outcome. In this study, we used the formalin-fixed, paraffin-embedded (FFPE) samples of ovarian tumor tissues from Vietnamese patients to detect pathogenic variants in BRCA1/BRCA2 via next-generation sequencing. DNA was extracted using QIAamp DNA FFPE Tissue Kit, and then its quality was assessed using BioDrop and Qubit. The BRCAaccuTestTM PLUS kit and Illumina MiSeqDx instrument were used for both library preparation and sequencing. All samples had passed the A260/280 ratio cut-off for DNA purity and the requirement of DNA concentration. Excepted for the 1st time, the percentage of ≥ Q30 was more than 80%, while the density was approximately 1,200 K/mm2, while the phasing and prephasing (%) metrics were satisfied to be less than 0.1%. 5 p...
Background The simple scoring systems for predicting the outcome of sepsis in intensive care unit... more Background The simple scoring systems for predicting the outcome of sepsis in intensive care units (ICUs) are few, especially for limited-resource settings. Therefore, this study aimed to evaluate the accuracy of the quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA) score in predicting the mortality of ICU patients with sepsis in Vietnam. Methods We did a multicenter cross-sectional study of patients with sepsis (≥18 years old) presenting to 15 adult ICUs throughout Vietnam on the specified days (i.e., 9th January, 3rd April, 3rd July, and 9th October) representing the different seasons of 2019. The primary and secondary outcomes were the hospital and ICU all-cause mortalities, respectively. The area under the receiver operating characteristic curve (AUROC) was calculated to determine the discriminatory ability of the qSOFA score for deaths in the hospital and ICU. The cut-off value of the qSOFA scores was determined by the receiver operating characteristic curve an...
Biochimica et Biophysica Acta (BBA) - Biomembranes, 2022
Amphiphysin and endophilin are two members of the N-BAR protein family. We have reported membrane... more Amphiphysin and endophilin are two members of the N-BAR protein family. We have reported membrane interactions of the helix 0 of endophilin (H0-Endo). Here we investigate membrane modulations caused by the helix 0 of amphiphysin (H0-Amph). Electron paramagnetic resonance (EPR) spectroscopy was used to explore membrane properties. H0-Amph was found to reduce lipid mobility, make the membrane interior more polar, and decrease lipid chain orientational order. The EPR data also showed that for anionic membranes, H0-Endo acted as a more potent modulator. For instance, at peptide-to-lipid (P/L) ratio of 1/20, the peak-to-peak splitting was increased by 0.27 G and 1.89 G by H0-Amph and H0-Endo, respectively. Similarly, H0-Endo caused a larger change in the bilayer polarity than H0-Amph (30% versus 12% at P/L = 1/20). At P/L = 1/50, the chain orientational order was decreased by 26% and 66% by H0-Amph and H0-Endo, respectively. The different capabilities were explained by considering hydrophobicity score distributions. We employed atomic force microscopy to investigate membrane structural changes. Both peptides caused the formation of micron-sized holes. Interestingly, only H0-Amph induced membrane fusion as evidenced by the formation of high-rise regions. Lastly, experiments of giant unilamellar vesicles showed that H0-Amph and H0-Endo generated thin tubules and miniscule vesicles, respectively. Together, our studies showed that both helices are effective in altering membrane properties; the observed changes might be important for membrane curvature induction. Importantly, comparisons between the two peptides revealed that the degree of membrane remodeling is dependent on the sequence of the N-terminal helix of the N-BAR protein family.
Synthesis and In vitro Performance of Polypyrrole coated Ironâ Platinum Nanoparticles for Phototh... more Synthesis and In vitro Performance of Polypyrrole coated Ironâ Platinum Nanoparticles for Photothermal Therapy and Photoacoustic Imaging. (DOCX 4483Â kb)
Ciprofloxacin imprinted polymers were prepared using co-precipitation polymerization of methacryl... more Ciprofloxacin imprinted polymers were prepared using co-precipitation polymerization of methacrylic acid, 2-vinylpyridine and polystyrene-co-divinylbenzene.
Macrophages are excellent imaging targets for detecting atherosclerotic plaques as they are invol... more Macrophages are excellent imaging targets for detecting atherosclerotic plaques as they are involved in all the developmental stages of atherosclerosis. However, no imaging technique is currently capable of visualizing macrophages inside blood vessel walls. The current study develops an intravascular ultrasonic-photoacoustic (IVUP) imaging system combined with indocyanine green (ICG) as a contrast agent to provide morphological and compositional information about the targeted samples. Both tissue-mimicking vessel phantoms and atherosclerotic plaque-mimicking porcine arterial tissues are used to demonstrate the feasibility of mapping macrophages labeled with ICG by endoscopically applying the proposed hybrid technique. A delay pulse triggering technique is able to sequentially acquire photoacoustic (PA) and ultrasound (US) signals from a single scan without using any external devices. The acquired PA and US signals are used to reconstruct 2D cross-sectional and 3D volumetric images of the entire tissue with the ICG-loaded macrophages injected. Due to high imaging contrast and sensitivity, the IVUP imaging vividly reveals structural information and detects the spatial distribution of the ICG-labeled macrophages inside the samples. ICG-assisted IVUP imaging can be a feasible imaging modality for the endoscopic detection of atherosclerotic plaques.
Abstract Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to thei... more Abstract Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to their high theoretical capacities, diverse functionalities, and environmental compatibility. Understanding the working mechanism of organic electrodes is vital to strategic materials design. However, due to lack of suitable characterization tools, it has been challenging to probe the reaction processes of organic electrodes in real-time. Here, non-destructive in situ electron paramagnetic resonance (EPR) was performed on a model organic electrode, 7,7,8,8-tetracyanoquinodimethane (TCNQ) used in rechargeable lithium-ion batteries, to directly follow the redox reactions in real-time. In order to minimize interfering signals from other parts of the batteries than the TCNQ electrode of interest, two sets of batteries are fabricated and studied with in situ EPR: (1) a LiCoO2//Li4Ti5O12 full-cell battery to determine the EPR signal evolution of additives and electrolytes; (2) a LiCoO2//TCNQ battery, and the difference in the observed EPR signals reflects purely the redox reactions of TCNQ upon lithiation and delithiation. A two-electron reversible redox reaction is delineated for TCNQ. TCNQ dimers form during the first electron injection upon lithiation and followed by the break-down of the dimers and associated electron coupling to produce massive delocalized electrons, resulting in increased EPR signal during the 2nd electron injection. Reversible trends are observed during electron ejection upon delithiation. In situ EPR is very sensitive to electron activities, thus is a powerful tool to follow redox reactions of organic electrodes, allowing for improved fundamental understanding of how organic electrodes work and for informed design of high-performance organic materials for energy storage.
This study synthesized cellulose-g-poly(acrylic acid) with high water absorbency using the cellul... more This study synthesized cellulose-g-poly(acrylic acid) with high water absorbency using the cellulose extracted from pineapple leaves. The synthesis experiment used a novel combination of ethylene glycol dimethacrylate (EGDMA) and azobisisobutyronitrile (AIBN) as the cross-linker and the initiator, respectively. Experimental results showed that the concentrations of AIBN and EGDMA had significant effects on the structure and the water absorbency of the cross-linked materials. The cellulose-g-poly(acrylic acid) synthesized with 0.5 wt% AIBN and 0.5 wt% EGDMA had an excellent swelling capacity of 1900 g/g in distilled water, significantly larger than previously reported ones. Compared with poly(acrylic acid), the cross-linked product demonstrated an absorbency improvement of 1.65 times in distilled water and 1.27 times in 8.6 ppm NaCl solution that was the highest salinity level in Ben Tre, Vietnam, in March 2020. Therefore, the obtained product showed high potential for agricultural applications, especially in coastal regions facing a growing thread of saltwater intrusion.
Journal of Advanced Biotechnology and Experimental Therapeutics
Ovarian cancer is one of the most popular causes of mortality among women, and the prevalence of ... more Ovarian cancer is one of the most popular causes of mortality among women, and the prevalence of ovarian cancer is increased. Early diagnosis of this disease via genetic variant testing is one potential strategy for enhancing treatment and disease outcome. In this study, we used the formalin-fixed, paraffin-embedded (FFPE) samples of ovarian tumor tissues from Vietnamese patients to detect pathogenic variants in BRCA1/BRCA2 via next-generation sequencing. DNA was extracted using QIAamp DNA FFPE Tissue Kit, and then its quality was assessed using BioDrop and Qubit. The BRCAaccuTestTM PLUS kit and Illumina MiSeqDx instrument were used for both library preparation and sequencing. All samples had passed the A260/280 ratio cut-off for DNA purity and the requirement of DNA concentration. Excepted for the 1st time, the percentage of ≥ Q30 was more than 80%, while the density was approximately 1,200 K/mm2, while the phasing and prephasing (%) metrics were satisfied to be less than 0.1%. 5 p...
Background The simple scoring systems for predicting the outcome of sepsis in intensive care unit... more Background The simple scoring systems for predicting the outcome of sepsis in intensive care units (ICUs) are few, especially for limited-resource settings. Therefore, this study aimed to evaluate the accuracy of the quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA) score in predicting the mortality of ICU patients with sepsis in Vietnam. Methods We did a multicenter cross-sectional study of patients with sepsis (≥18 years old) presenting to 15 adult ICUs throughout Vietnam on the specified days (i.e., 9th January, 3rd April, 3rd July, and 9th October) representing the different seasons of 2019. The primary and secondary outcomes were the hospital and ICU all-cause mortalities, respectively. The area under the receiver operating characteristic curve (AUROC) was calculated to determine the discriminatory ability of the qSOFA score for deaths in the hospital and ICU. The cut-off value of the qSOFA scores was determined by the receiver operating characteristic curve an...
Biochimica et Biophysica Acta (BBA) - Biomembranes, 2022
Amphiphysin and endophilin are two members of the N-BAR protein family. We have reported membrane... more Amphiphysin and endophilin are two members of the N-BAR protein family. We have reported membrane interactions of the helix 0 of endophilin (H0-Endo). Here we investigate membrane modulations caused by the helix 0 of amphiphysin (H0-Amph). Electron paramagnetic resonance (EPR) spectroscopy was used to explore membrane properties. H0-Amph was found to reduce lipid mobility, make the membrane interior more polar, and decrease lipid chain orientational order. The EPR data also showed that for anionic membranes, H0-Endo acted as a more potent modulator. For instance, at peptide-to-lipid (P/L) ratio of 1/20, the peak-to-peak splitting was increased by 0.27 G and 1.89 G by H0-Amph and H0-Endo, respectively. Similarly, H0-Endo caused a larger change in the bilayer polarity than H0-Amph (30% versus 12% at P/L = 1/20). At P/L = 1/50, the chain orientational order was decreased by 26% and 66% by H0-Amph and H0-Endo, respectively. The different capabilities were explained by considering hydrophobicity score distributions. We employed atomic force microscopy to investigate membrane structural changes. Both peptides caused the formation of micron-sized holes. Interestingly, only H0-Amph induced membrane fusion as evidenced by the formation of high-rise regions. Lastly, experiments of giant unilamellar vesicles showed that H0-Amph and H0-Endo generated thin tubules and miniscule vesicles, respectively. Together, our studies showed that both helices are effective in altering membrane properties; the observed changes might be important for membrane curvature induction. Importantly, comparisons between the two peptides revealed that the degree of membrane remodeling is dependent on the sequence of the N-terminal helix of the N-BAR protein family.
Synthesis and In vitro Performance of Polypyrrole coated Ironâ Platinum Nanoparticles for Phototh... more Synthesis and In vitro Performance of Polypyrrole coated Ironâ Platinum Nanoparticles for Photothermal Therapy and Photoacoustic Imaging. (DOCX 4483Â kb)
Ciprofloxacin imprinted polymers were prepared using co-precipitation polymerization of methacryl... more Ciprofloxacin imprinted polymers were prepared using co-precipitation polymerization of methacrylic acid, 2-vinylpyridine and polystyrene-co-divinylbenzene.
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