Publications by authors named "Haiyu Liu"

29 Publications

  • Page 1 of 1

Epileptiform activity in mouse hippocampal slices induced by moderate changes in extracellular Mg, Ca, and K.

BMC Neurosci 2021 Jul 23;22(1):46. Epub 2021 Jul 23.

Krembil Research Institute, University Health Network, Toronto, ON, Canada.

Background: Rodent brain slices-particularly hippocampal slices-are widely used in experimental investigations of epileptiform activity. Oxygenated artificial cerebrospinal fluid (ACSF) is used to maintain slices in vitro. Physiological or standard ACSF containing 3-3.5 mM K, 1-2 mM Mg, and 1-3 mM Ca generally does not induce population epileptiform activity, which can be induced by ACSF with high K (8-10 mM), low Mg, or low Ca alone or in combination. While low-Mg ACSF without intentionally added Mg salt but with contaminating Mg (≤ 50-80 µM) from other salts can induce robust epileptiform activity in slices, it is unclear whether such epileptiform activity can be achieved using ACSF with moderately decreased Mg. To explore this issue, we examined the effects of moderately modified (m)ACSF with 0.8 mM Mg, 1.3 mM Ca, and 5.7 mM K on induction of epileptiform discharges in mouse hippocampal slices.

Results: Hippocampal slices were prepared from young (21-28 days old), middle-aged (13-14 months old), and aged (24-26 months old) C57/BL6 mice. Conventional thin (0.4 mm) and thick (0.6 mm) slices were obtained using a vibratome and pretreated with mACSF at 35-36 °C for 1 h prior to recordings. During perfusion with mACSF at 35-36 °C, spontaneous or self-sustained epileptiform field potentials following high-frequency stimulation were frequently recorded in slices pretreated with mACSF but not in those without the pretreatment. Seizure-like ictal discharges were more common in thick slices than in thin slices.

Conclusions: Prolonged exposure to mACSF by pretreatment and subsequent perfusion can induce epileptiform field potentials in mouse hippocampal slices.
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http://dx.doi.org/10.1186/s12868-021-00650-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8305515PMC
July 2021

Electrographic Features of Spontaneous Recurrent Seizures in a Mouse Model of Extended Hippocampal Kindling.

Cereb Cortex Commun 2021 22;2(1):tgab004. Epub 2021 Jan 22.

Krembil Research Institute, University Health Network, Toronto, Ontario, Canada M5T 2S8.

Epilepsy is a chronic neurological disorder characterized by spontaneous recurrent seizures (SRS) and comorbidities. Kindling through repetitive brief stimulation of a limbic structure is a commonly used model of temporal lobe epilepsy. Particularly, extended kindling over a period up to a few months can induce SRS, which may simulate slowly evolving epileptogenesis of temporal lobe epilepsy. Currently, electroencephalographic (EEG) features of SRS in rodent models of extended kindling remain to be detailed. We explored this using a mouse model of extended hippocampal kindling. Intracranial EEG recordings were made from the kindled hippocampus and unstimulated hippocampal, neocortical, piriform, entorhinal, or thalamic area in individual mice. Spontaneous EEG discharges with concurrent low-voltage fast onsets were observed from the two corresponding areas in nearly all SRS detected, irrespective of associated motor seizures. Examined in brain slices, epileptiform discharges were induced by alkaline artificial cerebrospinal fluid in the hippocampal CA3, piriform and entorhinal cortical areas of extended kindled mice but not control mice. Together, these in vivo and in vitro observations suggest that the epileptic activity involving a macroscopic network may generate concurrent discharges in forebrain areas and initiate SRS in hippocampally kindled mice.
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http://dx.doi.org/10.1093/texcom/tgab004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8152854PMC
January 2021

Processing technology optimization for tofu curded by fermented yellow whey using response surface methodology.

Food Sci Nutr 2021 Jul 18;9(7):3701-3711. Epub 2021 May 18.

College of Food and Chemical Engineering Hunan Provincial Key Laboratory of Soybean Products Processing and Safety Control Shaoyang University Shaoyang China.

The technological applications utilized for tofu processing are diverse and complex, resulting in different yields and quality characteristics of tofu. The current study investigated the gel-forming principle of soybean protein coagulated using fermented yellow whey (FYW) to produce tofu. The effects of several processing parameters (soybean-to-water ratio, boiling temperature, boiling time, and FYW content) on the yield and protein content of tofu produced by the boiling-to-filtering method (BFM) were studied and optimized using response surface methodology. Results indicated significant differences in yield and protein content of tofu using different processing parameters, with FYW content being the most significant ( < .05). Optimum processing parameters of the BFM were found to be: soybean-to-water ratio of 1:5 (kg:kg), boiling time 6.1 min, boiling temperature 105°C, and FYW content of 26%. Under optimum conditions, tofu's yield and protein content were 235.17 g/100 g and 10.60%, respectively, and these were 47.93 g/100 g and 4.16% higher than those before optimization. This study provides practical technical support and a theoretical basis for the standardized industrial production of high-yield and high-protein tofu.
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http://dx.doi.org/10.1002/fsn3.2331DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8269558PMC
July 2021

Examinations of Bilateral Epileptiform Activities in Hippocampal Slices Obtained From Young Mice.

Front Cell Neurosci 2020 20;14:593840. Epub 2021 Jan 20.

Krembil Research Institute, University Health Network, Toronto, ON, Canada.

Bilateral interconnections through the hippocampal commissure play important roles in synchronizing or spreading hippocampal seizure activities. Intact hippocampi or bilateral hippocampal slices have been isolated from neonatal or immature rats (6-7 or 12-21 days old, respectively) and the mechanisms underlying the bilateral synchrony of hippocampal epileptiform activities have been investigated. However, the feasibility of examining bilateral epileptiform activities of more developed hippocampal circuitry remains to be explored. For this, we prepared bilateral hippocampal slices from C57 black mice, a strain commonly used in neuroscience and for genetic/molecular modifications. Young mice (21-24-day-old) were used in most experiments. A 600-μm-thick slice was obtained from each mouse by horizontal vibratome sectioning. Bilateral dorsal hippocampal and connecting dorsal hippocampal commissure (DHC) tissues were preserved in the slice and extrahippocampal tissues were removed. Slices were recorded in a submerged chamber mainly at a room temperature (21-22°C). Bilateral CA3 areas were monitored by extracellular recordings, and unilateral electrical stimulation was used to elicit CA3 synaptic field potentials. The unilateral stimulation could elicit population spikes in the contralateral CA3 area. These contralateral spikes were attenuated by inhibiting synaptic transmission with cobalt-containing medium and were abolished when a cut was made at the DHC. Self-sustained and bilaterally correlated epileptiform potentials were observed following application of 4-aminopyradine and became independent after the DHC cut. Bilateral hippocampal activities were detectable in some slices of adult mice and/or at 35-36°C, but with smaller amplitudes and variable waveforms compared to those observed from slices of young mice and at the room temperature. Together, these observations suggested that examining bilateral epileptiform activities in hippocampal slices of young mice is feasible. The weaknesses and limitations of this preparation and our experimentation are discussed.
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http://dx.doi.org/10.3389/fncel.2020.593840DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7854570PMC
January 2021

Fabricating MAPbI/MoS Composites for Improved Photocatalytic Performance.

Nano Lett 2021 Jan 1;21(1):597-604. Epub 2020 Dec 1.

Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University 199 Ren'ai Road, Suzhou 215123, Jiangsu, People's Republic of China.

Although lead halide perovskites are demonstrated to be promising photocatalysts for hydrogen evolution from hydrogen halide splitting, it still remains challenging to fabricate efficient and stable catalysts. Here MoS nanoflowers with abundant active sites are assembled with methylammonium lead iodide (MAPbI) microcrystals to form a new heterostructure. Its hydrogen evolution rate can reach up to about 30 000 μmol g h, which is more than 1000-fold higher than pristine MAPbI under visible light irradiation (λ ≥ 420 nm). Importantly, the solar HI splitting efficiency reaches 7.35%, one of the highest efficiencies so far. The introduction of MoS with proper band alignment and unsaturated species can efficiently promote the charge separation and afford more active sites for H production. This finding not only provides a highly efficient and stable photocatalyst for hydrogen evolution but also offers a useful modification strategy on lead halide perovskites.
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http://dx.doi.org/10.1021/acs.nanolett.0c04073DOI Listing
January 2021

Formation and Encapsulation of Lead Halide Perovskites in Lanthanide Metal-Organic Frameworks for Tunable Emission.

ACS Appl Mater Interfaces 2020 Feb 12;12(8):9851-9857. Epub 2020 Feb 12.

MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , Harbin 150001 , P. R. China.

Improving the stability of perovskite quantum dots and adjusting their optical properties are essential for their application in advanced optoelectronic equipment. We provide a simple synthetic method to hybridize perovskite quantum dots and metal-organic frameworks (MOFs) into a polymer matrix. The hybrid material is made by encapsulating perovskite CHNHPbBr quantum dots in lanthanide-based metal-organic frameworks. A series of lanthanide-based metal-organic frameworks (LnMOFs), namely, [Ln(tpob)(DMF)(HO)] (, Ln = Nd, Sm, Eu, Gd, Tb, Dy, Htpob = 1,3,5-tris(4-carbonylphenyloxy)benzene), have been synthesized under solvothermal conditions and fully characterized. s display a three-dimensional (3D) network with central-symmetric [Eu(COO)] structural building units (SBUs) linked by one-dimensional (1D) chains. hybrids were developed through a three-step process, in which the precursor was formed by immersing the crystal synthesized in the first step into a PbBr solution; then the composite materials could form quickly when CHNHBr was added to the precursor. Therefore, the hybrid composite material exhibits luminescent properties related to the excitation wavelength in the form of powders or thin films. In addition, the photoluminescence of the composite can be improved and maintained for a long time after it is introduced into the poly(methyl methacrylate) (PMMA) matrix. Moreover, the emission peak based on the perovskite quantum dots can still maintain about 85% of the original intensity after being left for 30 days. Also, the obtained PMMA films can achieve tunable emission from red to green.
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http://dx.doi.org/10.1021/acsami.9b23617DOI Listing
February 2020

Syntaxin-3 is dispensable for basal neurotransmission and synaptic plasticity in postsynaptic hippocampal CA1 neurons.

Sci Rep 2020 01 20;10(1):709. Epub 2020 Jan 20.

Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.

Recent evidence suggests that SNARE fusion machinery play critical roles in postsynaptic neurotransmitter receptor trafficking, which is essential for synaptic plasticity. However, the key SNAREs involved remain highly controversial; syntaxin-3 and syntaxin-4 are leading candidates for the syntaxin isoform underlying postsynaptic plasticity. In a previous study, we showed that pyramidal-neuron specific conditional knockout (cKO) of syntaxin-4 significantly reduces basal transmission, synaptic plasticity and impairs postsynaptic receptor trafficking. However, this does not exclude a role for syntaxin-3 in such processes. Here, we generated and analyzed syntaxin-3 cKO mice. Extracellular field recordings in hippocampal slices showed that syntaxin-3 cKO did not exhibit significant changes in CA1 basal neurotransmission or in paired-pulse ratios. Importantly, there were no observed differences during LTP in comparison to control mice. Syntaxin-3 cKO mice performed similarly as the controls in spatial and contextual learning tasks. Consistent with the minimal effects of syntaxin-3 cKO, syntaxin-3 mRNA level was very low in hippocampal and cortex pyramidal neurons, but strongly expressed in the corpus callosum and caudate axon fibers. Together, our data suggest that syntaxin-3 is dispensable for hippocampal basal neurotransmission and synaptic plasticity, and further supports the notion that syntaxin-4 is the major isoform mediating these processes.
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http://dx.doi.org/10.1038/s41598-019-57388-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6971263PMC
January 2020

Lanthanide Coordination Polymer-Based Composite Films for Selective and Highly Sensitive Detection of CrO in Aqueous Media.

Inorg Chem 2019 Nov 8;58(22):15118-15125. Epub 2019 Nov 8.

MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , Harbin 150001 , P. R. China.

Due to the high carcinogenicity and bioaccumulation effects of dichromate ions in the human body, sensitive and rapid detection of CrO ions is necessary. Herein, two lanthanide coordination polymers based on a linear dicarboxylic acid ligand, named {Ln(cpon)(Hcpon)(HO)} [Ln = Tb, ; Eu, ; H cpon = 5-(4-carboxy-phenoxy)-nicotinic acid], have been successfully synthesized. These two isostructural compounds contain one-dimensional zigzag chains that consist of uncoordinated carboxyl groups and pyridine groups in the framework, and the one-dimensional chains can further form a three-dimensional supramolecular stacking structure by intermolecular interaction. Both and show good luminescence performance and high stability. exhibits a good ability to sense CrO ions in aqueous solution. Moreover, the composite film material composed of and poly(methyl methacrylate) (PMMA) exhibits superior luminescence properties compared to those of pure . The film exhibits an excellent ability to recognize CrO ions with high selectivity and a low detection limit of 5.6 ppb, which is much lower than the maximum contamination standard of 100 ppb in drinking water specified by the U.S. Environmental Protection Agency. Furthermore, the film shows good recyclability for more than five cycles and anti-interference ability. After the introduction of the slightly soluble polymer poly(vinyl alcohol) (PVA), the composite film can effectively detect CrO ions in as little as 1 min. These composite films could be potentially used as test strips for trace detection and rapid detection of CrO ions in aqueous solution.
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http://dx.doi.org/10.1021/acs.inorgchem.9b01841DOI Listing
November 2019

Impaired Spatial Learning and Memory in Middle-Aged Mice with Kindling-Induced Spontaneous Recurrent Seizures.

Front Pharmacol 2019 24;10:1077. Epub 2019 Sep 24.

Krembil Research Institute, University Health Network, Toronto, ON, Canada.

Temporal lobe epilepsy is the most common and often drug-resistant type of epilepsy in the adult and aging populations and has great diversity in etiology, electro-clinical manifestations, and comorbidities. Kindling through repeated brief stimulation of limbic structures is a commonly used model of temporal lobe epilepsy. Particularly, extended kindling can induce spontaneous recurrent seizures in several animal species. However, kindling studies in middle-aged, aging, or aged animals remain scarce, and currently, little is known about kindling-induced behavioral changes in middle-aged/aging animals. We therefore attempted to provide more information in this area using a mouse model of extended hippocampal kindling. We conducted experiments in middle-aged mice (C57BL/6, male, 12-14 months of age) to model new-onset epilepsy in adult/aging populations. Mice experienced twice daily hippocampal stimulations or handling manipulations for 60-70 days and then underwent continuous electroencephalogram (EEG)-video monitoring to detect spontaneous recurrent seizures. Extended kindled mice consistently exhibited spontaneous recurrent seizures with mean incidences of 6-7 events per day, and these seizures featured EEG discharges and corresponding convulsions. The handling control mice showed neither seizure nor aberrant EEG activity. The two groups of mice underwent the Morris water maze test of spatial learning and memory 1-2 weeks after termination of the kindling stimulation or handling manipulation. During visible platform trials, the kindled mice took a longer distance and required more time than the control mice to find the platform. During hidden platform trials, the kindled mice showed no improvement over 5-day trials in finding the platform whereas the control mice improved significantly. During probe tests in which the hidden platform was removed, the kindled mice spent less time than the controls searching in the correct platform location. There were no significant differences between the kindled and control mice with respect to swim speed or total locomotor activity in an open-field test. Together, these observations indicate that the extended kindled mice with spontaneous recurrent seizures are impaired in spatial learning and memory as assessed by the Morris water maze test. We postulate that the extended hippocampal kindling in middle-aged mice may help explore epileptogenic mechanisms and comorbidities potentially relevant to new-onset temporal lobe epilepsy in adult and aging patients. Limitations and confounds of our present experiments are discussed to improve future examinations of epileptic comorbidities in extended kindled mice.
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http://dx.doi.org/10.3389/fphar.2019.01077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6768971PMC
September 2019

Fabricating CsPbX-Based Type I and Type II Heterostructures by Tuning the Halide Composition of Janus CsPbX/ZrO Nanocrystals.

ACS Nano 2019 May 17;13(5):5366-5374. Epub 2019 Apr 17.

Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices , Soochow University , 199 Ren'ai Road , Suzhou 215123 , Jiangsu , People's Republic of China.

Fabricating CsPbX-based heterostructures has proven to be a feasible way to tune their photophysical properties. Here, we report the successful fabrication of Janus CsPbX/ZrO heterostructure nanocrystals (NCs), in which each CsPbX NC is partially covered by ZrO. According to the band alignment, CsPbBr/ZrO and CsPbI/ZrO can be indexed as type I and type II composites, respectively. The type I composites display great enhancement in photoluminescence quantum yield (from 63 to 90%) and photoluminescence lifetime (from 12.9 to 66.1 ns) because of the charge carrier confinement and passivation effect provided by ZrO. In contrast, the type II composites can be used in photocatalytic reduction of CO because electrons and holes are effectively separated and accumulated in ZrO and CsPbI, respectively, under irradiation. Janus CsPbBr/ZrO NCs showed a stability much higher than that of pristine CsPbBr against polar solvent treatment. A stable and highly efficient light-emitting device with luminous efficiency up to 55 lm W is fabricated by using CsPbBr/ZrO NCs as the green light source. This work may not only enrich the family of surface-passivated perovskite materials but also provide a good example for the rational design of specific composites in the metal halide perovskite field.
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http://dx.doi.org/10.1021/acsnano.9b00001DOI Listing
May 2019

Improving the Stability and Size Tunability of Cesium Lead Halide Perovskite Nanocrystals Using Trioctylphosphine Oxide as the Capping Ligand.

Langmuir 2017 11 27;33(44):12689-12696. Epub 2017 Oct 27.

Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University , Suzhou, Jiangsu 215123, P. R. China.

Recently, all-inorganic cesium lead halide (CsPbX, X = Cl, Br, and I) nanocrystals (NCs) have drawn wide attention because of their excellent optoelectronic properties and potential applications. However, one of the most significant challenges of such NCs is their low stability against protonic solvents. In this work, we demonstrate that by incorporating a highly branched capping ligand, trioctylphosphine oxide (TOPO), into the traditional oleic acid/oleylamine system, monodisperse CsPbX NCs with excellent optoelectronic properties can be achieved at elevated temperatures (up to 260 °C). The size of such NCs can be varied in a relatively wide range. The capping of TOPO on NCs has been verified through Fourier transform infrared spectroscopy measurement. More importantly, the presence of TOPO can dramatically improve the stability of CsPbX NCs against ethanol treatment. After ethanol treatment for 100 min, the emission intensity of the TOPO-capped sample dropped only 5%, whereas that of non-TOPO-capped NCs dropped up to 86%. This work may shed some light on the preparation and application of CsPbX NCs with higher stability.
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http://dx.doi.org/10.1021/acs.langmuir.7b02963DOI Listing
November 2017

An integrated strategy by using target tissue metabolomics biomarkers as pharmacodynamic surrogate indices to screen antipyretic components of Qingkaikling injection.

Sci Rep 2017 07 24;7(1):6310. Epub 2017 Jul 24.

School of Chinese Material Medica, Beijing University of Chinese Medicine, South of Wangjing Middle Ring Road, Chaoyang District, Beijing, 100102, P.R. China.

Traditional Chinese medicine (TCM) treatment can be valuable therapeutic strategies. However, the active components and action mechanisms that account for its therapeutic effects remain elusive. Based on the hypothesis that the components of a formula which exert effect would be measurable in target tissue, a target tissue metabolomics-based strategy was proposed for screening of antipyretic components in Qingkaikling injection (QKLI). First, we detected the components of QKLI which could reach its target tissue (hypothalamus) by determining the hypothalamus microdialysate and discovered that only baicalin and geniposide could be detected. Then, by conducting hypothalamus metabolomics studies, 14 metabolites were screened as the potential biomarkers that related to the antipyretic mechanisms of QKLI and were used as its pharmacodynamic surrogate indices. Subsequently, the dynamic concentration of baicalin and geniposide in hypothalamus microdialysates and biomarkers in hypothalamus were measured and correlated with each other. The results indicated that only baicalin shown a good correlation with these biomarkers. Finally, a network pharmacology approach was established to validate the antipyretic activity of baicalin and the results elucidated its antipyretic mechanisms as well. The integrated strategy proposed here provided a powerful means for identifying active components and mechanisms contributing to pharmacological effects of TCM.
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http://dx.doi.org/10.1038/s41598-017-05812-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5524955PMC
July 2017

STMN1 as a candidate gene associated with atypical meningioma progression.

Clin Neurol Neurosurg 2017 Aug 10;159:107-110. Epub 2017 Jun 10.

Department of Neurosurgery of the First Clinical Hospital, Jilin University, Changchun, China; Department of Pathology & Laboratory Medicine, University of California, Irvine, CA, USA. Electronic address:

Objectives: Meningiomas are the most common type of primary intracranial tumor. Atypical meningiomas are especially difficult to manage due to frequent disease recurrence. This study aimed to examine the role of stathmin (coded by the gene STMN1) as a factor in atypical meningioma recurrence.

Patients And Methods: A total of 59 sporadic atypical meningioma formalin-fixed paraffin-embedded (FFPE) samples were collected. The mRNA levels of the biomarker gene STMN1 were tested using quantitative RT-PCR.

Results: We observed significant up-regulation of STMN1 mRNA expression in recurrent tumors in comparison with primary tumors (p<0.05). Moreover, mRNA expression levels of STMN1 significantly correlated with Ki-67 score (r=0.93, p<0.01). Multivariate survival analyses indicated that high expression of STMN1, high Ki-67 score, and more advanced patient age at diagnosis (>60yrs) each act as independence prognostic factors for recurrence. Kaplan-Meier analysis revealed that STMN1 expression pattern could effectively predict prognosis of atypical meningioma in patients (p<0.01).

Conclusions: Our study indicates for the first time that an increased risk of sporadic atypical meningioma recurrence can be found in cases with elevated expression of STMN1. These results suggest that STMN1 expression might serve as a biomarker for determining patient atypical meningioma prognosis.
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http://dx.doi.org/10.1016/j.clineuro.2017.06.003DOI Listing
August 2017

MicroRNA-10b mediates TGF-β1-regulated glioblastoma proliferation, migration and epithelial-mesenchymal transition.

Int J Oncol 2017 May 4;50(5):1739-1748. Epub 2017 Apr 4.

Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China.

Although it is well known that exaggerated proliferation, metastasis and the mesenchymal subtype is related with worst prognoses in glioblastoma (GBM) and that transforming growth factor-β1 (TGF-β1) is a potent factor in regulating the proliferation, migration and epithelial-mesenchymal transition (EMT) phenotype of GBM, the detailed mechanisms are still far from elucidated. MicroRNAs (miRNAs) are small non-coding RNAs which play critical roles in various diseases by regulating target gene expression. We report that miR-10b, a molecule downstream of TGF-β1, is involved in TGF-β1-regulated GBM cell proliferation, migration and EMT. We found that exposure of GBM cells to TGF-β1 significantly upregulated miR-10b expression. Overexpression of miR-10b promotes GBM cell proliferation, migration and EMT, whereas depletion of miR-10b obtained reverse effects. Further studies uncovered that some tumor-associated genes including epithelial cadherin (E-cadherin), apoptotic protease activating factor 1 (Apaf-1) and phosphatase and tensin homolog (PTEN) are target genes of miR-10b. In human GBM xenografts, antagomiR directed against miR-10b markedly suppressed tumor growth, and the tumor volume shrunk from 1252.5±285 to 873.4±205 mm3 after antagomiR‑10b treatment for 3 weeks compared with the control group (P<0.01). Taken together, our data collectively demonstrate that the proliferation, migration and EMT features of GBM cells can be regulated by TGF-β1 stimulation through controlling miR-10b. Thus, our findings provide a rationale for targeting TGF-β1 or miR-10b for the treatment of GBM.
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http://dx.doi.org/10.3892/ijo.2017.3947DOI Listing
May 2017

Current evidence on the cytotoxic T-lymphocyte antigen 4 + 49G > A polymorphism and digestive system cancer risks: a meta-analysis involving 11,923 subjects.

Meta Gene 2015 Dec 22;6:105-8. Epub 2015 Oct 22.

Wei Fang People's Hospital, Yu He Road 151#, Kui Wen District, Weifang, Shandong, China.

Cytotoxic T-lymphocyte antigen (CTLA-4) plays an important role in downregulating T cell activation and proliferation. The CTLA-4 + 49G > A polymorphism is one of the most commonly studied polymorphisms in this gene due to its association with many cancer types, but the association between CTLA-4 + 49G > A polymorphism and digestive system cancer risks remain inconclusive. An updated meta-analysis based on 17 independent case-control studies consisting of 5176 cancer patients and 6747 controls was performed to address this association. Overall, there was no statistically increased risk of digestive system cancers in every genetic comparison. In subgroup analysis, this polymorphism was significantly linked to higher risks for pancreatic cancer (GG vs. AA, OR = 1.976, 95% CI = 1.496-2.611; GA vs. AA, OR = 1.433, 95% CI = 1.093-1.879; GG/GA vs. AA, OR = 1.668, 95% CI = 1.286-2.164; GG vs. GA/AA, OR = 1.502, 95% CI = 1.098-2.054; G vs. A, OR = 1.394, 95% CI = 1.098-1.770). We also observed increased susceptibility of hepatocellular cell carcinoma in homozygote comparison (OR = 1.433, 95% CI = 1.100-1.866) and dominant model (OR = 1.360, 95% CI = 1.059-1.746). According to the source of controls, significant effects were only observed in hospital-based studies (GA/AA vs. GG, OR = 1.257, 95% CI = 1.129-1.399). In the stratified analysis by ethnicity, no significantly increased risks were found in either Asian or Caucasian. Our findings suggest that the CTLA-4 + 49G > A polymorphism may be associated with the risk of pancreatic cancer and hepatocellular cell carcinoma.
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http://dx.doi.org/10.1016/j.mgene.2015.09.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4634354PMC
December 2015

Hypothalamus metabolomic profiling to elucidate the tissue-targeted biochemical basis of febrile response in yeast-induced pyrexia rats.

Chem Biol Interact 2015 Apr 3;231:61-70. Epub 2015 Mar 3.

Science Experiment Centre for Traditional Chinese Medicine, Beijing University of Chinese Medicine, No. 11, North Third Ring Road, Chaoyang District, Beijing 100029, PR China. Electronic address:

In the previous reports regarding thermoregulation, the hypothalamus is thought to be the primary centre in the central nervous system for controlling the body temperature. However, to date, there has not been sufficient evidence to reveal its thermoregulatory mechanism. In the current study, we utilised a tissue-targeted metabolomics strategy to elucidate the underlying biochemical mechanisms of thermoregulation in the fever process by analysing the global metabolic profile of the hypothalamus in yeast-induced pyrexia rats. Data acquisition was completed using the HPLC-LTQ-Orbitrap/MS in both positive and negative ion mode. Principal component analysis was used to observe the cluster characteristics between the control group and the pyrexia group. Potential biomarkers were screened using orthogonal partial least-squares-discriminant analysis. Seventeen potential biomarkers were identified in the hypothalamus samples to discriminate the control and pyrexia groups, including amino acids, nucleic acids, vitamins, carbohydrates, and phospholipids. As a result, purine metabolism was enhanced pronouncedly, and perturbation of lipid metabolism was also observed. Meanwhile, amino acid metabolism and energy metabolism were also activated significantly. In conclusion, the study indicated that hypothalamus-targeted metabolomics could provide a powerful tool to further understand the pathogenesis of febrile response.
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http://dx.doi.org/10.1016/j.cbi.2015.02.018DOI Listing
April 2015

Global chemical profiling based quality evaluation approach of rhubarb using ultra performance liquid chromatography with tandem quadrupole time-of-flight mass spectrometry.

J Sep Sci 2015 Feb 7;38(3):511-22. Epub 2015 Jan 7.

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, P. R. China; Science Experiment Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, P. R. China.

A global chemical profiling based quality evaluation approach using ultra performance liquid chromatography with tandem quadrupole time-of-flight mass spectrometry was developed for the quality evaluation of three rhubarb species, including Rheum palmatum L., Rheum tanguticum Maxim. ex Balf., and Rheum officinale Baill. Considering that comprehensive detection of chemical components is crucial for the global profile, a systemic column performance evaluation method was developed. Based on this, a Cortecs column was used to acquire the chemical profile, and Chempattern software was employed to conduct similarity evaluation and hierarchical cluster analysis. The results showed R. tanguticum could be differentiated from R. palmatum and R. officinale at the similarity value 0.65, but R. palmatum and R. officinale could not be distinguished effectively. Therefore, a common pattern based on three rhubarb species was developed to conduct the quality evaluation, and the similarity value 0.50 was set as an appropriate threshold to control the quality of rhubarb. A total of 88 common peaks were identified by their accurate mass and fragmentation, and partially verified by reference standards. Through the verification, the newly developed method could be successfully used for evaluating the holistic quality of rhubarb. It would provide a reference for the quality control of other herbal medicines.
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http://dx.doi.org/10.1002/jssc.201400971DOI Listing
February 2015

A metabolomic strategy to screen the prototype components and metabolites of Qingkailing injection in rat urine by high-performance liquid chromatography with tandem mass spectrometry.

J Sep Sci 2014 Oct;37(20):2844-50

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, P.R. China; Science Experiment Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, P.R. China.

Xenobiotic metabolome identification of Chinese herbal formula in biological systems is a very challenging task. Qingkailing injection is a typical Chinese herbal injection, which is wildly used clinically in China. However, the holistic metabolic fate of the ingredient from Qingkailing injection remains unclear. In this work, a metabolomic strategy for comprehensively elucidating Qingkailing injection derived prototype components and metabolites in rat urine conducted by hybrid linear ion trap high-resolution mass spectrometry was developed. High-performance liquid chromatography coupled with hybrid linear ion trap high-resolution mass spectrometry was developed to obtain the urine profiling between the control group and Qingkailing injection treated group. Orthogonal partial least squares discriminate analysis was applied to distinguish the exogenous and the endogenous. In the S-plot, 37 xenobiotics derived from Qingkailing injection were found in urine, including 18 prototype compounds and 19 metabolites. The characterization of the prototype components and metabolites in rat's urine provided essential data for further pharmacological studies of Qingkailing injection. Our results indicated that the metabolomic approach was an effective tool to discover, screen, and analyze the multiple prototype components and their metabolites from complicated traditional Chinese preparations in vivo.
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http://dx.doi.org/10.1002/jssc.201400339DOI Listing
October 2014

Plasma metabolomic profiling to reveal antipyretic mechanism of Shuang-huang-lian injection on yeast-induced pyrexia rats.

PLoS One 2014 18;9(6):e100017. Epub 2014 Jun 18.

School of Chinese material medica, Beijing University of Chinese Medicine, Beijing, China.

Shuang-huang-lian injection (SHLI) is a famous Chinese patent medicine, which has been wildly used in clinic for the treatment of acute respiratory tract infection, pneumonia, influenza, etc. The existing randomized controlled trial (RCT) studies suggested that SHLI could afford a certain anti-febrile action. However, seldom does research concern the pharmacological mechanisms of SHLI. In the current study, we explored plasma metabolomic profiling technique and selected potential metabolic markers to reveal the antipyretic mechanism of SHLI on yeast-induced pyrexia rat model using UPLC-Q-TOF/MS coupled with multivariate statistical analysis and pattern recognition techniques. We discovered a significant perturbance of metabolic profile in the plasma of fever rats and obvious reversion in SHLI-administered rats. Eight potential biomarkers, i.e. 1) 3-hydeoxybutyric acid, 2) leucine, 3) 16:0 LPC, 4) allocholic acid, 5) vitamin B2, 6) Cys-Lys-His, 7) 18:2 LPC, and 8) 3-hydroxychola-7, 22-dien-24-oic acid, were screened out by OPLS-DA approach. Five potential perturbed metabolic pathways, i.e. 1) valine, leucine, and isoleucine biosynthesis, 2) glycerophospholipid metabolism, 3) ketone bodies synthesis and degradation, 4) bile acid biosynthesis, and 5) riboflavin metabolism, were revealed to relate to the antipyretic mechanisms of SHLI. Overall, we investigated antipyretic mechanisms of SHLI at metabolomic level for the first time, and the obtained results highlights the necessity of adopting metabolomics as a reliable tool for understanding the holism and synergism of Chinese patent drug.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0100017PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4062457PMC
October 2015

One single amino Acid for estimation the content of total free amino acids in qingkailing injection using high-performance liquid chromatography-diode array detection.

J Anal Methods Chem 2014 13;2014:951075. Epub 2014 Mar 13.

Science Experiment Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North Third Ring Road, Chaoyang District, Beijing 100029, China.

Qingkailing injection (QKLI), a modern traditional Chinese medicine preparation, has been widely used in clinics due to its fast and significant efficacy in treatment of high fever. The free amino acids (AAs) were considered to be the most abundant active ingredients indisputably. So developing an accurate and simple determination method to measure the contents of total free AAs in QKLI is very crucial. In current study, the accurate and simple method of using one single standard AA for simultaneous quantification of multiple AAs (One for M) in QKLI was developed. Particularly, the calculation methods and the robustness of relative correction factors (RCFs) were investigated systematically. No statistically significant difference between these two quantification methods of One for M and classic regression equation was found by the t-test (P  =  95%, P > 0.05). The results showed that the precision (RSD < 4.88%), the robustness (RSD < 4.04%), and the average recoveries (94.11%-107.94%) of this newly proposed method all met the requirements for content determination. This One for M method will provide a scientific reference for the quantitative determination of AAs in other traditional Chinese medicines and their preparations owing to its accuracy and simplicity.
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http://dx.doi.org/10.1155/2014/951075DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3976834PMC
April 2014

A Metabolomic Strategy to Screen the Prototype Components and Metabolites of Shuang-Huang-Lian Injection in Human Serum by Ultra Performance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry.

J Anal Methods Chem 2014 26;2014:241505. Epub 2014 Feb 26.

Science Experiment Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, No. 11, North Third Ring Road, Chaoyang District, Beijing 100029, China.

Shuang-huang-lian injection (SHLI) is a famous Chinese patent medicine, which has been wildly used in clinic to treat acute respiratory tract infection, pneumonia, influenza, and so forth. Despite the widespread clinical application, the prototype components and metabolites of SHLI have not been fully elucidated, especially in human body. To discover and screen the constituents or metabolites of Chinese medicine in biofluids tends to be more and more difficult due to the complexity of chemical compositions, metabolic reactions and matrix effects. In this work, a metabolomic strategy to comprehensively elucidate the prototype components and metabolites of SHLI in human serum conducted by UPLC-Q-TOF/MS was developed. Orthogonal partial least squared discriminant analysis (OPLS-DA) was applied to distinguish the exogenous, namely, drug-induced constituents, from endogenous in human serum. In the S-plot, 35 drug-induced constituents were found, including 23 prototype compounds and 12 metabolites which indicated that SHLI in human body mainly caused phase II metabolite reactions. It was concluded that the metabolomic strategy for identification of herbal constituents and metabolites in biological samples was successfully developed. This identification and structural elucidation of the chemical compounds provided essential data for further pharmacological and pharmacokinetics study of SHLI.
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http://dx.doi.org/10.1155/2014/241505DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3955581PMC
April 2014

Characterization of rational biomarkers accompanying fever in yeast-induced pyrexia rats using urine metabolic footprint analysis.

J Pharm Biomed Anal 2014 Jul 26;95:68-75. Epub 2014 Feb 26.

Key Laboratory of TCM-Information Engineering of State Administration of Traditional Chinese Medicine, School of Chinese Materia Medica, Beijing University of Chinese Medicine, South of Wangjing Middle Ring Road, Chaoyang District, Beijing 100102, PR China.

Fever is a prominent feature of diseases and is an ongoing process that is always accompanied by metabolic changes in the body system. Despite the success of temperature regulation theory, the underlying biological process remains unclear. To truly understand the nature of the febrile response, it is crucial to confirm the biomarkers during the entire biological process. In the current study, a 73-h metabolic footprint analysis of the urine from yeast-induced pyrexia rats was performed using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Potential biomarkers were selected using orthogonal partial least squares-discriminate analysis (OPLS-DA), the rational biomarkers were verified by Pearson correlation analysis, and the predictive power was evaluated using receiver operator characteristic (ROC) curves. A metabolic network constructed using traditional Chinese medicine (TCM) grammar systems was used to validate the rationality of the verified biomarkers. Finally, five biomarkers, including indoleacrylic acid, 3-methyluridine, tryptophan, nicotinuric acid and PI (37:3), were confirmed as rational biomarkers because their correlation coefficients were all greater than 0.87 and because all of the correlation coefficients between any pair of these biomarkers were higher than 0.75. The areas under the ROC curves were all greater than 0.84, and their combined predictive power was considered reliable because the greatest area under the ROC curve was 0.968. A metabolic network also demonstrated the rationality of these five biomarkers. Therefore, these five metabolites can be adopted as rational biomarkers to reflect the process of the febrile response in inflammation-induced pyrexia.
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http://dx.doi.org/10.1016/j.jpba.2014.02.011DOI Listing
July 2014

Microembolic signals detected with transcranial doppler sonography differ between symptomatic and asymptomatic middle cerebral artery stenoses in Northeast China.

PLoS One 2014 14;9(2):e88986. Epub 2014 Feb 14.

The Neuroscience Center, Department of Neurology, The First Hospital of Jilin University, Jilin University, Changchun, China.

Although microembolus monitoring has been widely used for ischemic cerebrovascular disease, the clinical significance of microembolic signal (MES) in asymptomatic middle cerebral artery (MCA) stenosis remains unclear. We aim to investigate the frequency of MES and the value of MES in predicting ischemic stroke secondary to asymptomatic MCA stenosis. From June 2011 to December 2012, microembolus monitoring was performed in 83 asymptomatic and 126 symptomatic subjects. By comparing the demographics and risk factors between the symptomatic and asymptomatic subjects, we found that the ratio of male sexuality and smoking history differed (101/126 vs 43/83, and 88/126 vs 38/83, respectively, p<0.01). The frequency of MES was significantly higher in the symptomatic group than in the asymptomatic group (49/126 vs 2/108, p<0.01). Specifically, the frequency of MES in the symptomatic and asymptomatic groups with mild stenosis, moderate stenosis, severe stenosis and occlusion groups was 4/18 (22.22%) vs 0/30 (0), 13/31 (41.94%) vs 1/28 (3.57%), 30/62 (48.39%) vs 1/39 (2.56%), 2/15 (13.33%) vs 0/11 (0), respectively. Except for the occlusive group, the frequency of MES is correlated with stenosis degree and symptom. Two patients in the asymptomatic group were found positive for MES, and the MES number was 1 for both. During the one-year follow-up, neither of them developed ischemic stroke. In conclusion, MES detected with TCD differs between symptomatic and asymptomatic MCA stenoses. Due to the low frequency, the value of MES as a predictor of subsequent ischemic stroke in patients with asymptomatic MCA stenosis might be limited.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0088986PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3925204PMC
October 2014

A rapid and sensitive UPLC-MS/MS method for quantification of two caffeoylquinic acids and four main active components in rat plasma after an intravenous administration of Qingkailing injection and its application to a pharmacokinetic study.

Biomed Chromatogr 2014 May 4;28(5):601-9. Epub 2013 Nov 4.

Science Experiment Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North Third Ring Road, Chaoyang District, Beijing, 100029, People's Republic of China.

Qingkailing (QKL) injection, a modified modern Chinese medicine preparation, is widely used in the clinic for its significant antipyretic and anti-inflammatory effects, but its serious adverse drug reactions have attracted more and more attention. Series of caffeoylquinic acids in QKL are widely suspected to be the allergens responsible for these adverse drug reactions. Therefore, pharmacokinetic studies of the caffeoylquinic acids are needed. In this paper, a simple, rapid and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of chlorogenic acid, neochlorogenic acid, baicalin, geniposide, cholic acid and hyodeoxycholic acid in rat plasma. Chromatographic separation was achieved on a BEH C18 column by a gradient elution at a flow rate of 0.40 mL/min in only 6.0 min. All analytes were monitored by multiple reaction monitoring mode with negative electrospray ionization. The calibration curves of these analytes were all linear (r > 0.9978) over wide concentration ranges. The intra- and inter- day precisions (relative standard deviations) were within 14.3% and accuracy (relative error) ranged from -6.8 to 4.8%. The mean recoveries ranged from 74.5 to 105.6%. This validated method was successfully applied to the pharmacokinetic study of the six analytes in rats following an intravenous administration of QKL injection.
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http://dx.doi.org/10.1002/bmc.3077DOI Listing
May 2014

UPLC Q-TOF/MS-Based Metabolic Profiling of Urine Reveals the Novel Antipyretic Mechanisms of Qingkailing Injection in a Rat Model of Yeast-Induced Pyrexia.

Evid Based Complement Alternat Med 2013 6;2013:864747. Epub 2013 Jun 6.

Science Experiment Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North Third Ring Road, Chaoyang District, Beijing 100029, China.

Fever is one of the most common clinical symptoms of many diseases. Qingkailing (QKL) injection is widely used in China as a clinical emergency medicine due to its good antipyretic effects. It is a herbal formula which is composed by eight kinds of traditional Chinese medicines (TCM). As a kind of typical multiple constituents and multiple actions of TCM, it is very difficult to elaborate the antipyretic mechanism by conventional pharmacological method. Metabonomics technique provides beneficial tool for this challenge. In this study, an ultra performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC Q-TOF/MS) metabonomics method was developed to explore the changing process of biochemical substances in rats of yeast-induced pyrexia. Partial least squares discriminate analysis (PLS-DA) was used to distinguish the normal control group, the pyrexia model group, and the pyrexia model group treated by QKL injection. The potential biomarkers related to pyrexia were confirmed and identified. MetPA was used to find the possible metabolic pathways. The results indicated that the antipyretic effect of QKL injection on yeast-induced pyrexia rats was performed by repairing the perturbed metabolism of amino acids.
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http://dx.doi.org/10.1155/2013/864747DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3690234PMC
July 2013

Comparative mitogenomic analysis of damsel bugs representing three tribes in the family Nabidae (Insecta: Hemiptera).

PLoS One 2012 28;7(9):e45925. Epub 2012 Sep 28.

Department of Entomology, China Agricultural University, Beijing, China.

Background: Nabidae, a family of predatory heteropterans, includes two subfamilies and five tribes. We previously reported the complete mitogenome of Alloeorhynchus bakeri, a representative of the tribe Prostemmatini in the subfamily Prostemmatinae. To gain a better understanding of architecture and evolution of mitogenome in Nabidae, mitogenomes of five species representing two tribes (Gorpini and Nabini) in the subfamily Nabinae were sequenced, and a comparative mitogenomic analysis of three nabid tribes in two subfamilies was carried out.

Methodology/principal Findings: Nabid mitogenomes share a similar nucleotide composition and base bias, except for the control region, where differences are observed at the subfamily level. In addition, the pattern of codon usage is influenced by the GC content and consistent with the standard invertebrate mitochondrial genetic code and the preference for A+T-rich codons. The comparison among orthologous protein-coding genes shows that different genes have been subject to different rates of molecular evolution correlated with the GC content. The stems and anticodon loops of tRNAs are extremely conserved, and the nucleotide substitutions are largely restricted to TψC and DHU loops and extra arms, with insertion-deletion polymorphisms. Comparative analysis shows similar rates of substitution between the two rRNAs. Long non-coding regions are observed in most Gorpini and Nabini mtDNAs in-between trnI-trnQ and/or trnS2-nad1. The lone exception, Nabis apicalis, however, has lost three tRNAs. Overall, phylogenetic analysis using mitogenomic data is consistent with phylogenies constructed mainly form morphological traits.

Conclusions/significance: This comparative mitogenomic analysis sheds light on the architecture and evolution of mitogenomes in the family Nabidae. Nucleotide diversity and mitogenomic traits are phylogenetically informative at subfamily level. Furthermore, inclusion of a broader range of samples representing various taxonomic levels is critical for the understanding of mitogenomic evolution in damsel bugs.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0045925PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3461043PMC
February 2013

The complete mitochondrial genome of the damsel bug Alloeorhynchus bakeri (Hemiptera: Nabidae).

Int J Biol Sci 2012 24;8(1):93-107. Epub 2011 Nov 24.

Department of Entomology, China Agricultural University, Beijing 100193, China.

The complete sequence of the mitochondrial DNA (mtDNA) of the damsel bug, Alloeorhynchus bakeri, has been completed and annotated in this study. It represents the first sequenced mitochondrial genome of heteropteran family Nabidae. The circular genome is 15, 851 bp in length with an A+T content of 73.5%, contains the typical 37 genes that are arranged in the same order as that of the putative ancestor of hexapods. Nucleotide composition and codon usage are similar to other known heteropteran mitochondrial genomes. All protein-coding genes (PCGs) use standard initiation codons (methionine and isoleucine), except COI, which started with TTG. Canonical TAA and TAG termination codons are found in eight protein-coding genes, the remaining five (COI, COII, COIII, ND5, ND1) have incomplete termination codons (T or TA). PCGs of two strands present opposite CG skew which is also reflected by the nucleotide composition and codon usage. All tRNAs have the typical clover-leaf structure, except the dihydrouridine (DHU) arm of tRNA(Ser (AGN))which forms a simple loop as known in many other metazoa. Secondary structure models of the ribosomal RNA genes of A. bakeri are presented, similar to those proposed for other insect orders. There are six domains and 45 helices and three domains and 27 helices in the secondary structures of rrnL and rrnS, respectively. The major non-coding region (also called control region) between the small ribosomal subunit and the tRNA(Ile )gene includes two special regions. The first region includes four 133 bp tandem repeat units plus a partial copy of the repeat (28 bp of the beginning), and the second region at the end of control region contains 4 potential stem-loop structures. Finally, PCGs sequences were used to perform a phylogenetic study. Both maximum likelihood and Bayesian inference analyses highly support Nabidae as the sister group to Anthocoridae and Miridae.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3248651PMC
http://dx.doi.org/10.7150/ijbs.8.93DOI Listing
October 2012

The architecture and complete sequence of mitochondrial genome of an assassin bug Agriosphodrus dohrni (Hemiptera: Reduviidae).

Int J Biol Sci 2011 1;7(6):792-804. Epub 2011 Jul 1.

Department of Entomology, China Agricultural University, Beijing 100193, China.

The 16, 470 bp nucleotide sequence of the mitochondrial genome (mitogenome) of an assassin bug from the reduviid subfamily Harpactorinae, Agriosphodrus dohrni, has been revealed. The entire genome encodes for two ribosomal RNA genes (rrnL and rrnS), 22 transfer RNA (tRNA) genes, 13 protein-coding genes, and a control region. The nucleotide composition is biased toward adenine and thymine (A+T = 72.2%). Comparative analysis with two other reduviid species Triatoma dimidiata and Valentia hoffmanni, exhibited highly conserved genome architectures including genome contents, gene order, nucleotide composition, codon usage, amino acid composition, as well as genome asymmetry. All protein-coding genes use standard mitochondrial initiation codons (methionine and isoleucine), except that nad1 starts with GTG. All tRNAs have the classic clover-leaf structure, except that the dihydrouridine (DHU) arm of tRNA(Ser(AGN)) forms a simple loop. Secondary structure comparisons of the two mitochondrial ribosomal subunits among sequenced assassin bugs show that the sequence and structure of rrnL is more conservative than that of rrnS. The presence of structural elements in the control region is also discussed, with emphasis on their implications in the regulation of replication and/or transcription of the reduviid mitogenome. The phylogenetic analyses indicated that within Reduviidae, Harpactorinae is a sister group to the Salyavatinae + Triatominae clade.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3133887PMC
http://dx.doi.org/10.7150/ijbs.7.792DOI Listing
November 2011

Study on fusion characteristics of biomass ash.

Bioresour Technol 2010 Dec 22;101(23):9373-81. Epub 2010 Jul 22.

State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, 710049 Shaanxi, China.

The ash fusion characteristics (AFC) of Capsicum stalks ashes, cotton stalks ashes and wheat stalks ashes that all prepared by ashing at 400 degrees C, 600 degrees C and 815 degrees C are consistent after 860 degrees C, 990 degrees C and 840 degrees C, respectively in the ash fusion temperature test and TG. Initial deformation temperature (IDT) increases with decreased K(2)O and went up with increased MgO, CaO, Fe(2)O(3) and Al(2)O(3). Softening temperature (ST), hemispherical temperature (HT) and fluid temperature (FT) do not affected by the concentrations of each element and the ashing temperature obviously. Therefore, the IDT may be as an evaluation index of biomass AFC rather than the ST used as an evaluation index of coal AFC. XRD shows that no matter what the ashing temperature is, the biomass ashes contain same high-temperature molten material. Therefore, evaluation of the biomass AFC should not be simply on the proportion of elements except IDT, but the high-temperature molten material in biomass ash.
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http://dx.doi.org/10.1016/j.biortech.2010.06.144DOI Listing
December 2010
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