53 results on '"Guo AJ"'
Search Results
2. Metabolic changes in schizophrenia and human brain evolution
- Author
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Khaitovich, P, Lockstone, HE, Wayland, MT, Tsang, TM, Jayatilaka, SD, Guo, AJ, Zhou, J, Somel, M, Harris, LW, Holmes, E, Paeaebo, S, Bahn, S, OpenMETU, Wayland, Matthew [0000-0002-8095-858X], and Apollo - University of Cambridge Repository
- Subjects
Adult ,Male ,Pan troglodytes ,Bioinformatics ,Formal thought-disorder ,05 Environmental Sciences ,Nmr-Spectroscopy ,Gene Expression ,behavioral disciplines and activities ,Homo-sapiens ,Cognition ,mental disorders ,Animals ,Humans ,RNA, Messenger ,Gene-expression ,Magnetic-resonance-spectroscopy ,Nuclear Magnetic Resonance, Biomolecular ,Aged ,Oligonucleotide Array Sequence Analysis ,Genetics & Heredity ,Science & Technology ,Human genome ,Research ,Gene Expression Profiling ,Brain ,06 Biological Sciences ,Middle Aged ,Biological Evolution ,Macaca mulatta ,Positive selection ,Biotechnology & Applied Microbiology ,Dysfunction ,Schizophrenia ,Cortex ,Female ,08 Information and Computing Sciences ,sense organs ,Proton ,Energy Metabolism ,Life Sciences & Biomedicine - Abstract
Human cognitive evolution involved genes implicated in energy metabolism and energy-expensive brain functions that are also altered in schizophrenia, suggesting that human brains may have reached their metabolic limit, with schizophrenia as a costly by-product., Background Despite decades of research, the molecular changes responsible for the evolution of human cognitive abilities remain unknown. Comparative evolutionary studies provide detailed information about DNA sequence and mRNA expression differences between humans and other primates but, in the absence of other information, it has proved very difficult to identify molecular pathways relevant to human cognition. Results Here, we compare changes in gene expression and metabolite concentrations in the human brain and compare them to the changes seen in a disorder known to affect human cognitive abilities, schizophrenia. We find that both genes and metabolites relating to energy metabolism and energy-expensive brain functions are altered in schizophrenia and, at the same time, appear to have changed rapidly during recent human evolution, probably as a result of positive selection. Conclusion Our findings, along with several previous studies, suggest that the evolution of human cognitive abilities was accompanied by adaptive changes in brain metabolism, potentially pushing the human brain to the limit of its metabolic capabilities.
- Published
- 2008
3. Biomarkers associated with immune-related adverse events induced by immune checkpoint inhibitors.
- Author
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Guo AJ, Deng QY, Dong P, Zhou L, and Shi L
- Abstract
Immune checkpoint inhibitors (ICIs) constitute a pivotal class of immunotherapeutic drugs in cancer treatment. However, their widespread clinical application has led to a notable surge in immune-related adverse events (irAEs), significantly affecting the efficacy and survival rates of patients undergoing ICI therapy. While conventional hematological and imaging tests are adept at detecting organ-specific toxicities, distinguishing adverse reactions from those induced by viruses, bacteria, or immune diseases remains a formidable challenge. Consequently, there exists an urgent imperative for reliable biomarkers capable of accurately predicting or diagnosing irAEs. Thus, a thorough review of existing studies on irAEs biomarkers is indispensable. Our review commences by providing a succinct overview of major irAEs, followed by a comprehensive summary of irAEs biomarkers across various dimensions. Furthermore, we delve into innovative methodologies such as machine learning, single-cell RNA sequencing, multiomics analysis, and gut microbiota profiling to identify novel, robust biomarkers that can facilitate precise irAEs diagnosis or prediction. Lastly, this review furnishes a concise exposition of irAEs mechanisms to augment understanding of irAEs prediction, diagnosis, and treatment strategies., Competing Interests: Conflict-of-interest statement: The authors declare no competing or financial interests., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)
- Published
- 2024
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4. Allergic Bronchopulmonary Mycosis with Eosinophilia Caused by Schizophyllum Infection.
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Yuan XH, Chen QC, Wang Y, Hao JH, Guo AJ, Zhang JB, Fu AS, and Ge YL
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- Humans, Eosinophilia diagnosis, Eosinophilia microbiology, Male, Bronchoscopy, High-Throughput Nucleotide Sequencing, Tomography, X-Ray Computed, Lung Diseases, Fungal diagnosis, Lung Diseases, Fungal microbiology, Lung Diseases, Fungal drug therapy, Middle Aged, Mycoses diagnosis, Mycoses microbiology, Mycoses drug therapy, Mycoses complications, Schizophyllum isolation & purification, Schizophyllum genetics, Antifungal Agents therapeutic use
- Abstract
Background: As an opportunistic pathogenic fungus, Schizophyllum has been rarely reported to infect humans. By reporting a case of definite diagnosis of Schizophyllum infection, we aim to improve clinicians' understanding of this bacterium., Methods: By reporting a case with cough and sputum as the main manifestations, after empirical antiinfective chest CT suggesting a more progressive inflammatory lesion and a mass-like lesion in the paratracheal area of the main airways, a diagnosis of Schizophyllum infection was finally made by bronchoscopy with the delivery of metagenomic next-generation sequencing (mNGS)., Results: The patient was finally diagnosed with rare Schizophyllum infection. After antifungal treatment, the symptoms improved, and the patient was discharged., Conclusions: Although Schizophyllum is a rare fungal infection, it should be taken seriously in patients with diabetes or who are immunocompromised. At the same time, mNGS plays a key role in the detection of rare and emerging pathogens, which is worthy of clinical interest.
- Published
- 2024
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5. Investigating the crowding effect of FDI on domestic investments: Evidence from Bangladesh.
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Guo AJ, Ahmed SF, Mohsin AKM, Rahman A, Abdullah SN, Onn CW, and Islam MS
- Abstract
This study empirically investigates the crowding effect of Foreign Direct Investment (FDI) on domestic investments in Bangladesh, utilizing annual time series data from 1972 to 2022. Initially, unit root tests are conducted with and without considering structural breaks in the dataset. This study employs the Johansen test of cointegration to investigate the enduring association between the variables and utilizes the Vector Error Correction Model (VECM) to accommodate this relationship over the long term. Following the estimation of the VECM, formulas about the magnitude of the crowding effect (CE) are applied to examine the impact of FDI on domestic investment in Bangladesh. Results indicate that FDI positively influences domestic investments in both the short and long run., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)
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- 2024
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6. AAV9-based PMM2 gene replacement augments PMM2 expression and improves glycosylation in primary fibroblasts of patients with phosphomannomutase 2 deficiency (PMM2-CDG).
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Zhong M, Balakrishnan B, Guo AJ, and Lai K
- Abstract
Inherited deficiency of phosphomannomutase 2 (PMM2) (aka PMM2-CDG) is the most common congenital disorders of glycosylation (CDG) and has no cure. With debilitating morbidity and significant mortality, it is imperative to explore novel, safe, and effective therapies for the disease. Our Proof-of-Concept study showed that AAV9- PMM2 infection of patient fibroblasts augmented PMM2 expression and improved glycosylation. Thus, AAV9- PMM2 gene replacement is a promising therapeutic strategy for PMM2-CDG patients., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors.)
- Published
- 2023
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7. Apoptotic contraction drives target cell release by cytotoxic T cells.
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Sanchez EE, Tello-Lafoz M, Guo AJ, de Jesus M, Elbanna YA, Winer BY, Budhu S, Chan E, Rosiek E, Kondo T, DuSold J, Taylor N, Altan-Bonnet G, Olson MF, and Huse M
- Subjects
- Perforin, Granzymes, T-Lymphocytes, Cytotoxic, Apoptosis genetics
- Abstract
Cytotoxic T lymphocytes (CTLs) fight intracellular pathogens and cancer by identifying and destroying infected or transformed target cells
1 . To kill, CTLs form a specialized cytotoxic immune synapse (IS) with a target of interest and then release toxic perforin and granzymes into the interface to elicit programmed cell death2-5 . The IS then dissolves, enabling CTLs to search for additional prey and professional phagocytes to clear the corpse6 . While the mechanisms governing IS assembly have been studied extensively, far less is known about target cell release. Here, we applied time-lapse imaging to explore the basis for IS dissolution and found that it occurred concomitantly with the cytoskeletal contraction of apoptotic targets. Genetic and pharmacological perturbation of this contraction response indicated that it was both necessary and sufficient for CTL dissociation. We also found that mechanical amplification of apoptotic contractility promoted faster CTL detachment and serial killing. Collectively, these results establish a biophysical basis for IS dissolution and highlight the importance of mechanosensory feedback in the regulation of cell-cell interactions., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)- Published
- 2023
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8. Inhibition of Ca 2+ -calpain signaling is a new mechanism using Laminaria japonica polysaccharide to prevent macrophage foam cell formation and atherosclerosis.
- Author
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Li XY, Kuang DD, Guo AJ, Deng YY, Pan LH, Li QM, Luo JP, and Zha XQ
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- Animals, Mice, Foam Cells, Calpain metabolism, Calpain pharmacology, Macrophages, Lipoproteins, LDL metabolism, Signal Transduction, Polysaccharides pharmacology, Polysaccharides metabolism, Autophagy, Laminaria metabolism, Atherosclerosis drug therapy, Atherosclerosis metabolism
- Abstract
The Ca
2+ -calpain signaling plays a pivotal role in regulating the upstream signaling pathway of cellular autophagy. The aim of the current work was to investigate the role of Ca2+ -calpain signaling in the regulation of macrophage autophagy by a Laminaria japonica polysaccharide (LJP61A) in Ox-LDL induced macrophages and high fat diet fed atherosclerotic mice. Results revealed that the LJP61A markedly decreased the levels of intracellular Ca2+ , calpain1, calpain2 and their downstream effectors (Gsα, cAMP and IP3), and simultaneously enhanced autophagy activity and lipid metabolism, thereby reducing lipid accumulation in the Ox-LDL stimulated macrophages and lipid-laden plaques in atherosclerotic mice. Moreover, BAPTA-AM (a Ca2+ chelator) and calpeptin (a calpain inhibitor) synergistically strengthened the beneficial effects of LJP61A on autophagy and lipid metabolism by decreasing the levels of intracellular Ca2+ , calpain1, calpain2, and their downstream effectors (Gsα, cAMP and IP3) induced by Ox-LDL. These findings suggested that the LJP61A suppressed macrophage derived foam cell formation and atherosclerosis by modulating the Ca2+ -calpain-mediated autophagy.- Published
- 2023
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9. Determination of 24 sulfonamide antibiotics in instant pastries by modified QuEChERS coupled with ultra performance liquid chromatography-tandem mass spectrometry.
- Author
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Li S, Zhang C, Tang HX, Gu Y, Guo AJ, Wang K, and Lian KQ
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- Sulfonamides chemistry, Sulfonamides pharmacology, Eggs, Chromatography, Liquid, Tandem Mass Spectrometry, Anti-Bacterial Agents pharmacology
- Abstract
There were few reports about antibiotic residues in egg-containing products. In the study, an effective method for the simultaneous determination of 24 sulfonamide antibiotics in two instant pastries based on a modified QuEChERS sample preparation technique coupled with ultra performance liquid chromatography-tandem mass spectrometry was developed. The results show that the average recoveries of the SAs at 5, 10, and 50 μg kg
-1 levels were 67.6%-103.8%, with relative standard deviations (RSD) of 0.80-9.23%. The limit of detections (LODs) and limit of quantitations (LOQs) were 0.01-0.14 μg kg-1 and 0.02-0.45 μg kg-1 , respectively. This method was suitable for analysis of 24 SAs in instant pastries.- Published
- 2023
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10. Echinococcosis Is Associated with the Increased Prevalence of Intestinal Blastocystis Infection in Tibetans and Host Susceptibility to the Blastocystis in Mice.
- Author
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Zou Y, Wang YG, Liu ZL, Guo AJ, Li XL, Shi ZQ, Zhu XQ, Han XM, and Wang S
- Abstract
Blastocystis is a common human intestinal protozoan parasite. Little is known about its prevalence in echinococcosis. This study tested whether Echinococcus multilocularis infection would increase host susceptibility to Blastocystis. A total of 114 fecal samples (68 hydatid disease patients and 46 healthy people) were collected from Tibetans in the Qinghai province in China. The presence of Blastocystis was identified by sequencing of the small subunit (SSU) rRNA gene. Balb/c mice were co-infected with Blastocystis and E. multilocularis and tested for host susceptibility to Blastocystis. The overall Blastocystis prevalence was 12.3%; 16.2% in the patients and 4.4% in healthy people (p < 0.05). Sequence analysis identified three known Blastocystis genotypes, including ST1, ST2, and ST3, and one unknown genotype. Experimental dual infection significantly reduced mouse survival rate (20%), induced more severe signs, and increased intestinal damages with a higher intestinal colonization level of Blastocystis. The mouse model showed that E. multilocularis infection increases host susceptibility to Blastocystis. Our study shows a significantly higher prevalence of Blastocystis in patients with liver echinococcosis and reveals that non-intestinal E. multilocularis infection increases host susceptibility to the Blastocystis. Our results highlight that E. multilocularis infection is associated with Blastocystis. These findings remind us that more attention should be paid to the gut health of the patients with a helminth infection during clinical patient care.
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- 2022
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11. Associations of urinary dichloroacetic acid and trichloroacetic acid exposure with platelet indices: Exploring the mediating role of blood pressure in the general population.
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Zhang SH, Guo AJ, Wei N, Zhang R, and Niu YJ
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- Adult, Blood Pressure, China, Cross-Sectional Studies, Humans, Dichloroacetic Acid, Trichloroacetic Acid toxicity
- Abstract
Human exposure to drinking water disinfection by-products (DBPs) is potentially linked to high blood pressure (BP), which may be associated with abnormal platelet activation. This study investigated whether the relationship between DBP exposure with platelet change was mediated by BP. DBP biomarkers, such as urinary dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), BP and platelet indices from 505 adults from a hospital in Shijiazhuang, China were measured. The cross-sectional associations among DCAA and TCAA exposure, BP and platelet indices were explored through multivariable linear regressions, and the mediation effect of BP was evaluated using the Sobel-Goodman test. We observed that DCAA and TCAA were positively associated with systolic BP (all p for trends < 0.01), which was positively associated with platelet count (PLC) (p for trend < 0.05). Mediation analysis indicated that systolic BP fully mediated the associations of DCAA and TCAA with PLC. When BP was controlled, a previously inverse significant relation between DCAA and platelet distribution width (PDW) remained significant (p < 0.05). Obtained results suggested that exposure to DCAA may contribute to decreased PDW in humans. Systolic BP is a possible mediator of the association between DCAA exposure and PLC. TCAA may indirectly positively affect PLC by increasing systolic BP., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2021
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12. Proteome Analyses Reveal S100A11, S100P, and RBM25 Are Tumor Biomarkers in Colorectal Cancer.
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Guo AJ, Wang FJ, Ji Q, Geng HW, Yan X, Wang LQ, Tie WW, Liu XY, Thorne RF, Liu G, and Xu AM
- Abstract
Purpose: The prognosis for colorectal cancer (CRC) patients is drastically impacted by the presence of lymph node or liver metastases at diagnosis or resection. On this basis it is sought to identify novel proteins as biomarkers and determinants of CRC metastasis., Experimental Design: Proteomic analyses are undertaken using primary tissues from ten Chinese CRC patients presenting with or without liver metastases and immunohistochemistry used to validate selected proteins in an independent patient cohort., Results: Comparing CRC against paired normal adjacent tissues identifies 1559 differentially expressed proteins (DEPs) with 974 upregulated and 585 downregulated proteins, respectively. The highest number of DEPs is selectively associated with metastatic tumors (519 upregulated and 267 downregulated proteins, respectively) with a smaller number of unique DEPs identified only in non-metastatic CRC cases (116 upregulated and 29 downregulated proteins, respectively). The remaining DEPs are commonly expressed in both non-metastatic and metastatic tumors. The upregulation of three representative DEPs (S100A11, S100P, and RBM25) is confirmed using immunohistochemistry against 154 CRC tissues embedded in a tissue microarray., Conclusions and Clinical Relevance: The data reveal both previously identified CRC biomarkers along with novel candidates which provide a ready resource of DEPs in CRC for further investigation., (© 2020 Wiley-VCH GmbH.)
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- 2021
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13. Newly excysted juveniles of Fasciola gigantica trigger the release of water buffalo neutrophil extracellular traps in vitro.
- Author
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Guo AJ, Wang L, Meng XL, Zhang SH, Sheng ZA, Wei ZK, Luo XN, Huang WY, Zhu XQ, Zhang XC, and Cai XP
- Abstract
Polymorphonuclear neutrophils (PMNs) are the most abundant leukocytes and are among the first line of immune system defense. PMNs can form neutrophil extracellular traps (NETs) in response to some pathogens. The release of NETs plays an important role in trapping and killing invading parasites. However, the effects of NETs on parasitic trematode infections remain unclear. In the present study, water buffalo NET formation, triggered by the newly excysted juveniles (NEJs) of Fasciola gigantica, was visualized by scanning electron microscopy. The major components of the structure of NETs were characterized by immunofluorescence. Viability of flukes incubated with water buffalo PMNs were examined under light microscopy. The results revealed that F. gigantic juveniles triggered PMN-mediated NETs. These NETs were confirmed to comprise the classic characteristics of NETs: DNA, histones, myeloperoxidase and neutrophil elastase. Although NETs were formed in response to viable larvae, the larvae were not killed in vitro. These results suggest that NET formation may serve as a mechanism to hamper the migration of large larvae to facilitate immune cells to kill them. This study demonstrates, for the first time, that parasitic trematode juveniles can trigger NET formation., (Copyright © 2019. Published by Elsevier Inc.)
- Published
- 2020
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14. Multiscale Simulation on Product Distribution from Pyrolysis of Styrene-Butadiene Rubber.
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Deng S, Zhuo H, Wang Y, Leng S, Zhuang G, Zhong X, Wei Z, Yao Z, and Wang AJ
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Pyrolysis of styrene-butadiene rubber receives renewed attention due to its application in tackling the waste tire disposal problem while allowing energy recovery. The density functional theory calculation (DFT) and ReaxFF molecular dynamics simulation (MD) are adopted to study the pyrolysis process with the variation of temperature and pressure. The bond dissociation energies of intramonomer and intermonomer bonds in trimers with different linking methods are calculated by DFT, where the bond with low energy tends to break during the pyrolysis process. The following MD simulation shows the pyrolysis product distribution of chain segments in styrene-butadiene rubber, where bond breaking positions in MD agree well with corresponding results in DFT and experiment. The next nearest neighbor bonds (single bonds) connected with double bond or benzene usually have lower dissociation energies than other single bonds and prone to break during the pyrolysis process. And thus, the intermonomer bonds tend to break at relatively low temperatures (around 650 K in experiment) prior to intramonomer bonds, which result in the emergence of monomers. With the temperature increase, intramonomer bonds are broken and thus large fragments are further pyrolyzed into small ones (e.g., C
2 and C). Besides, the pressure strongly influences the product distribution, where high pressures promote the occurrence of secondary reactions., Competing Interests: The authors declare no conflict of interest.- Published
- 2019
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15. Urinary trichloroacetic acid and high blood pressure: A cross-sectional study of general adults in Shijiazhuang, China.
- Author
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Zhang SH, Guo AJ, Zhao WX, Gu JL, Zhang R, and Wei N
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- Adult, Biomarkers, Blood Pressure, China epidemiology, Cross-Sectional Studies, Humans, Environmental Exposure statistics & numerical data, Environmental Pollutants urine, Hypertension epidemiology, Trichloroacetic Acid urine
- Abstract
Exposure to trichloroacetic acid (TCAA) and its parent chemicals potentially linked to cardiovascular disease. However, the association between TCAA and blood pressure (BP) has not been studied to date. The purpose of this study was to examine the potential association between urinary TCAA levels and BP in a Chinese population. We measured BP parameters (including systolic BP, diastolic BP and pulse pressure) and TCAA concentrations in the urine of 569 adults from a primary health care clinic in Shijiazhuang, China. Logistic and linear regressions were used to investigate the relationships between the urinary TCAA levels and BP parameters. To evaluate the robustness of the results, we conducted sensitivity analyses by re-analysing data after excluding urine samples with extreme specific creatinine values. We found that urine TCAA levels were positively associated with systolic BP and pulse pressure based on trend tests after adjusting for potential confounders (both p for trend < 0.05). Finally, only the association of TCAA with systolic BP remained significant in the sensitivity analyses (p < 0.05). Our results suggested that TCAA exposure was associated with increased BP in adults. Because urinary TCAA has been proposed as a valid biomarker of disinfection by-product (DBP) ingestion through disinfected drinking water, our results further suggest that exposure to drinking water DBPs may contribute to high BP in humans. Additional research is needed to confirm these findings and to evaluate opportunities for intervention., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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16. Phthalates in residential and agricultural soils from an electronic waste-polluted region in South China: distribution, compositional profile and sources.
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Zhang SH, Guo AJ, Fan TT, Zhang R, and Niu YJ
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- Agriculture, Carbon analysis, China, Esters analysis, Recycling, Soil chemistry, Electronic Waste analysis, Environmental Monitoring, Phthalic Acids analysis, Soil Pollutants analysis
- Abstract
Electronic waste (e-waste) recycling has proven to be a significant source of phthalate (PAE) contamination in the environment. A detailed investigation was conducted to understand the concentration, distribution, profile and possible source of PAEs in residential and agricultural soils from Guiyu, Shantou, China, the largest e-waste processing and recycling areas in the world. Sixteen PAEs were analysed in 46 surface soil samples from three different sampling areas in terms of individual and total concentrations, together with pH and soil organic matter. High concentrations of the total PAEs were found in residential area A (more than 20,000 ng g
-1 ), revealing a clear urban pulse, whereas in residential area B and agricultural areas, concentrations were lower than 10,000 ng g-1 . The dominant PAEs were bis (2-nbutoxyethyl) phthalate, bis (4-methyl-2-pentyl) phthalate and dicyclohexyl phthalate. These PAEs were high-molecular weight PAEs (alkyl chains ≥ 6 carbons) and mainly derived from polyvinyl chloride commonly used in electrical and electronic equipment, indicating a distinctive composition in relation to the e-waste area. Three individual and the total PAEs exhibited significant positive correlations with pH. Principal component analysis indicated that PAEs were mainly distributed in three groups according to the alkyl chain length and potential source. This study showed that the informal e-waste recycling has already introduced PAEs into surrounding areas as a pollutant which should draw more attention and regulatory control.- Published
- 2019
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17. Reply to the letter 'Thrombolytic therapy to the patients with de Winter electrocardiographic pattern, not right'.
- Author
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Rao MY, Wang YL, Zhang GR, Zhang Y, Liu T, Guo AJ, Li L, Zhou K, and Wang M
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- Humans, Electrocardiography, Thrombolytic Therapy
- Published
- 2019
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18. Thrombolytic therapy to the patients with de Winter electrocardiographic pattern, is it right?
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Rao MY, Wang YL, Zhang GR, Zhang Y, Liu T, Guo AJ, Li L, Zhou K, and Wang M
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- Cardiac Catheterization, Coronary Angiography, Coronary Occlusion diagnosis, Drug-Eluting Stents, Electrocardiography, Female, Humans, Male, Middle Aged, Coronary Occlusion drug therapy, Thrombolytic Therapy methods
- Published
- 2018
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19. Expression profiles of genes involved in TLRs and NLRs signaling pathways of water buffaloes infected with Fasciola gigantica.
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Zhang FK, Hou JL, Guo AJ, Tian AL, Sheng ZA, Zheng WB, Huang WY, Elsheikha HM, and Zhu XQ
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- Animals, Cattle, Cattle Diseases immunology, Fasciola pathogenicity, Fascioliasis immunology, Fascioliasis veterinary, Host-Parasite Interactions genetics, Host-Parasite Interactions immunology, Leukocytes, Mononuclear metabolism, NLR Proteins genetics, Signal Transduction genetics, Signal Transduction immunology, Toll-Like Receptors genetics, Transcriptome, Buffaloes genetics, Buffaloes immunology, Buffaloes parasitology, Cattle Diseases genetics, Fasciola immunology, Fascioliasis genetics, Immunity, Innate genetics, NLR Proteins metabolism, Toll-Like Receptors metabolism
- Abstract
Infection of ruminants and humans with Fasciola gigantica is attracting increasing attention due to its economic impact and public health significance. However, little is known of innate immune responses during F. gigantica infection. Here, we investigated the expression profiles of genes involved in Toll-like receptors (TLRs) and NOD-like receptors (NLRs) signaling pathways in buffaloes infected with 500F. gigantica metacercariae. Serum, liver and peripheral blood mononuclear cell (PBMC) samples were collected from infected and control buffaloes at 3, 10, 28, and 70days post infection (dpi). Then, the levels of 12 cytokines in serum samples were evaluated by ELISA. Also, the levels of expression of 42 genes, related to TLRs and NLRs signaling, in liver and PBMCs were determined using custom RT
2 Profiler PCR Arrays. At 3 dpi, modest activation of TLR4 and TLR8 and the adaptor protein (TICAM1) was detected. At 10 dpi, NF-κB1 and Interferon Regulatory Factor signaling pathways were upregulated along with activation of TLR1, TLR2, TLR6, TLR10, TRAF6, IRF3, TBK1, CASP1, CD80, and IFNA1 in the liver, and inflammatory response with activated TLR4, TLR9, TICAM1, NF-κB1, NLRP3, CD86, IL-1B, IL-6, and IL-8 in PBMCs. At 28 dpi, there was increase in the levels of cytokines along with induction of NLRP1 and NLRP3 inflammasomes-dependent immune responses in the liver and PBMCs. At 70 dpi, F. gigantica activated TLRs and NLRs, and their downstream interacting molecules. The activation of TLR7/9 signaling (perhaps due to increased B-cell maturation and activation) and upregulation of NLRP3 gene were also detected. These findings indicate that F. gigantica alters the expression of TLRs and NLRs genes to evade host immune defenses. Elucidation of the roles of the downstream effectors interacting with these genes may aid in the development of new interventions to control disease caused by F. gigantica infection., (Copyright © 2017. Published by Elsevier Ltd.)- Published
- 2018
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20. Serum levels of cytokines in water buffaloes experimentally infected with Fasciola gigantica.
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Zhang FK, Guo AJ, Hou JL, Sun MM, Sheng ZA, Zhang XX, Huang WY, Elsheikha HM, and Zhu XQ
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- Animals, Buffaloes, Cytokines blood, Enzyme-Linked Immunosorbent Assay veterinary, Fascioliasis parasitology, Fasciola immunology, Fascioliasis veterinary
- Abstract
Fasciola gigantica infection in water buffaloes causes significant economic losses especially in developing countries. Although modulation of the host immune response by cytokine neutralization or vaccination is a promising approach to control infection with this parasite, our understanding of cytokine's dynamic during F. gigantica infection is limited. To address this, we quantified the levels of serum cytokines produced in water buffaloes following experimental infection with F. gigantica. Five buffaloes were infected via oral gavage with 500 viable F. gigantica metacercariae and blood samples were collected from buffaloes one week before infection and for 13 consecutive weeks thereafter. The levels of 10 cytokines in serum samples were simultaneously determined using ELISA. F. gigantica failed to elicit the production of various pro-inflammatory cytokines, including interleukin-1β (IL-1β), IL-2, IL-6, IL-12, and IFN-γ. On the other hand, evidence of a Th2 type response was detected, but only early in the course of parasite colonization and included modest increase in the levels of IL-10 and IL-13. The results also revealed suppression of the immune responses as a feature of chronic F. gigantica infection in buffaloes. Taken together, F. gigantica seems to elicit a modest Th2 response at early stage of infection in order to downregulate harmful Th1- and Th17-type inflammatory responses in experimentally infected buffaloes. The full extent of anti-F. gigantica immune response and its relation to pathogenesis requires further study., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
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21. Transcriptomic responses of water buffalo liver to infection with the digenetic fluke Fasciola gigantica.
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Zhang FK, Zhang XX, Elsheikha HM, He JJ, Sheng ZA, Zheng WB, Ma JG, Huang WY, Guo AJ, and Zhu XQ
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- Animals, Buffaloes genetics, Buffaloes metabolism, Cattle, Cattle Diseases metabolism, Fasciola hepatica genetics, Fascioliasis metabolism, Fascioliasis parasitology, Liver metabolism, Buffaloes parasitology, Cattle Diseases genetics, Cattle Diseases parasitology, Fasciola hepatica physiology, Fascioliasis genetics, Fascioliasis veterinary, Liver parasitology, Transcriptome
- Abstract
Background: Fasciola gigantica, the tropical liver fluke, infects buffaloes in Asian and African countries and causes significant economic losses and poses public health threat in these countries. However, little is known of the transcriptional response of buffaloes to infection with F. gigantica. The objective of the present study was to perform the first transcriptomic analysis of buffalo liver infected by F. gigantica. Understanding the mechanisms that underpin F. gigantica infection in buffaloes will contribute to our ability to control this parasite., Methods: We challenged buffaloes with 500 viable F. gigantica metacercariae and collected liver samples through a time course at 3, 42 and 70 days post-infection (dpi). Then, we performed gene expression analysis on liver samples using RNA sequencing (RNA-Seq) Illumina technology and confirmed the RNA-Seq data by quantitative RT-PCR analysis., Results: Totals of 496, 880 and 441 differentially expressed transcripts were identified in the infected livers at 3, 42 and 70 dpi, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that transcriptional changes in the liver of infected buffaloes evolve over the course of infection. The predominant response of buffaloes to infection was mediated by certain pathways, such as MHC antigen processing and presentation, Toll-like receptor 4 (TLR4), transforming growth factor beta (TGF-β), and the cytochrome P450. Hepatic drug metabolizing enzymes and bile secretion were also affected., Conclusions: Fasciola gigantica can induce statistically significant and biologically plausible differences in the hepatic gene expression of infected buffaloes. These findings provide new insights into the response of buffaloes to F. gigantica over the course of infection, which may be useful in determining pathways that can modulate host-parasite interaction and thus potentially important for clearance of the parasite.
- Published
- 2017
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22. [Identification, Expression and Antigenicity Analysis of Serpin B6 of Taenia solium].
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Liu GX, Zhang SH, Guo AJ, Hou JL, Wei YL, Wang S, and Luo XN
- Subjects
- Amino Acid Sequence, Animals, Blotting, Western, Cysticercus, Electrophoresis, Polyacrylamide Gel, Escherichia coli, Phylogeny, Serpins, Swine, Taenia solium
- Abstract
Objective: To identify and express serpin B6 of Taenia solium (Tsserpin B6) and explore its possible use as a diagnostic antigen., Methods: Primers for Tsserpin B6 were designed according to T. solium genome and transcriptome data. The Tsserpin B6 gene was amplified from the total RNA of T. solium cysticercus and subsequently analyzed by bioinformatics. Multiple amino acid sequence alignments of Tsserpin B6 and other parasites serpins were created using the Clustal X1.83. Phylogenetic analyses were performed using the MEGA 6.0. The recombinant expression vector pET-30a-Tsserpin B6 was constructed and expressed in E. coli strain BL21 (DE3). The expressed proteins were purified, isolated by SDS-PAGE, and analyzed by Western blotting using pig serum infected with T. solium cysticerci., Results: The complete reading frame of Tsserpin B6 was 1 131 bp and encoded a protein of 376 amino acids. The encoded protein had a conservative reactive center loop and distinctive domains of NEEGAE and FTVDHPFLF, and harbored 9 potential linear B cell epitopes. The expressed products of Tsserpin B6 mainly existed as an inclusion body, and reacted with pig serum infected with T. solium, resulting in a specific band at the Mr 53 000., Conclusion: The Tsserpin B6 gene was successfully cloned, and its expressed products can be recognized by pig serum infected with T. solium.
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- 2016
23. [Identification of Taenia solium Insulin Receptor TsIR-1316 and Expression of Its Ligand Binding Domain].
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Wei YL, Guo AJ, Zhang SH, Liu GX, Hou JL, and Luo XN
- Subjects
- Amino Acid Sequence, Animals, Blotting, Western, Cloning, Molecular, Immune Sera, Polymerase Chain Reaction, Rabbits, Receptor, Insulin, Recombinant Proteins, Taenia, Taenia solium
- Abstract
Objective: To characterize the structure of insulin receptor of Taenia solium(TsIR-1316) and express its ligand binding domain (LBD)., Methods: Primers for TsIR-1316 were designed according to the genomic data of T. solium, and the TsIR-1316 gene was amplified by PCR. The nucleotide and amino acid sequences of TsIR-1316 were aligned using BLASTN and BLASTP, and the putative signal peptide and structure domains were predicted. The LBD fragment of TsIR-1316 was cloned into the pET-30a(+) vector and expressed. The expressed proteins were purified, separated by SDS-PAGE and analyzed with Western blotting using cysticercus cellulosae-positive serum and TsIR-LBD-immunized rabbit serum., Results: The open reading frame of TsIR-1316 was 5 196 bp, encoded a protein of 1 732 amino acids which had a typical conserved domain of tyrosine kinase family, was 84% homologous with Echinococcus multilocularis, and had a “V”-shaped tertiary structure. As expected, SDS-PAGE showed that the expressed protein had a band at Mr 59 000. Western blotting showed that the recombinant protein had specific reactions with cysticercus cellulosae positive serum and TsIR-LBD immunized rabbit serum, resulting in a specific band at M(r) 59 000., Conclusion: The TsIR-1316 gene was successfully cloned and identified. The expressed protein of TsIR-1316 LBD can be recognized by cysticercus cellulosae positive serum, which suggests a good antigenicity of this protein.
- Published
- 2016
24. Overexpression of NUAK1 is associated with disease-free survival and overall survival in patients with gastric cancer.
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Ye XT, Guo AJ, Yin PF, Cao XD, and Chang JC
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- Adult, Aged, Aged, 80 and over, Disease-Free Survival, Female, Humans, Lymphatic Metastasis pathology, Male, Middle Aged, Prognosis, Proportional Hazards Models, Stomach Neoplasms pathology, Stomach Neoplasms surgery, Survival Analysis, Biomarkers, Tumor metabolism, Protein Kinases metabolism, Repressor Proteins metabolism, Stomach Neoplasms metabolism, Stomach Neoplasms mortality
- Abstract
Novel (nua) kinase family 1 (NUAK1) is a member of the human adenosine monophosphate-activated protein kinases family, which is overexpressed in multiple human malignancies and thought to be involved in tumor invasion and metastasis ability. Our study is to investigate the association of NUAK1 expression with clinicopathological parameters and prognostic significance of patients with gastric cancer. The expression patterns of the NUAK1 protein in 117 primary archival gastric cancer specimens and 46 adjacent normal epithelial tissues from patients were detected by immunohistochemistry assay. Staining evaluation results were analyzed statistically in relation to various clinicopathological characters, recurrence-free survival and overall survival. High level of NUAK1 expression was detected in gastric cancer, significantly more than in adjacent normal epithelial cells. In gastric cancer, NUAK1 was positively correlated with depth of invasion, lymph node metastasis, pathological stage, surgical resection and histological differentiation. However, no correlations between NUAK1 expression and patients' age, sex, tumor size, location, CA19-9 or CEA were detected. The recurrence-free survival and overall survival were significantly shorter for patients with NUAK1 higher scores than those with NUAK1 lower scores. Multivariate analysis identified NUAK1 was an independent prognostic factor for both recurrence-free survival and overall survival. Our findings provided convincing evidence for NUAK1 overexpression, which was tightly associated with more aggressive tumor behavior and a poor prognosis, indicating that NUAK1 is a valuable molecular biomarker for gastric cancer progression. It might also act as a promising target for both prognostic prediction and therapeutics.
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- 2014
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25. Chemical fingerprinting and quantitative analysis of two common Gleditsia sinensis fruits using HPLC-DAD.
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Chen J, Li Z, Zheng KY, Guo AJ, Zhu KY, Zhang WL, Zhan JY, Dong TT, Su Z, and Tsim KW
- Subjects
- Fruit, Oleanolic Acid chemistry, Oleanolic Acid isolation & purification, Saponins chemistry, Chromatography, High Pressure Liquid methods, Gleditsia chemistry, Oleanolic Acid analogs & derivatives, Saponins isolation & purification
- Abstract
Gleditsiae Fructus Abnormalis and Gleditsiae Sinensis Fructus are obtained from different developmental stages of fruits from Gleditsia sinensis Lam. (Leguminosae). The possible interchangeable usage of the two fruits, however, has long been very controversial. Here, high performance liquid chromatography coupled with diode array detection was developed to explore their chemical fingerprinting profiles. Besides, the amounts of aglycones of saponin compounds, echinocystic acid and oleanolic acid in both fruits were quantified. The results indicated that there was no significant difference in the content of aglycones from the two types of fruits. However, their chromatographic fingerprints showed distinct characteristics. Therefore, the interchangeable application of these fruits has to be taken with a specific precaution.
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- 2013
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26. Synergistic Action of Flavonoids, Baicalein, and Daidzein in Estrogenic and Neuroprotective Effects: A Development of Potential Health Products and Therapeutic Drugs against Alzheimer's Disease.
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Choi RC, Zhu JT, Yung AW, Lee PS, Xu SL, Guo AJ, Zhu KY, Dong TT, and Tsim KW
- Abstract
Despite the classical hormonal effect, estrogen has been reported to mediate neuroprotection in the brain, which leads to the searching of estrogen-like substances for treating neurodegenerative diseases. Flavonoids, a group of natural compounds, are well known to possess estrogenic effects and used to substitute estrogen, that is, phytoestrogen. Flavonoid serves as one of the potential targets for the development of natural supplements and therapeutic drugs against different diseases. The neuroprotection activity of flavonoids was chosen for a possible development of anti-Alzheimer's drugs or food supplements. The estrogenic activity of two flavonoids, baicalein and daidzein, were demonstrated by their strong abilities in stimulating estrogen receptor phosphorylation and transcriptional activation of estrogen responsive element in MCF-7 breast cells. The neuroprotection effects of flavonoids against β -amyloid (A β ) were revealed by their inhibition effects on in vitro A β aggregation and A β -induced cytotoxicity in PC12 neuronal cells. More importantly, the estrogenic and neuroprotective activities of individual flavonoid could be further enhanced by the cotreatment in the cultures. Taken together, this synergistic effect of baicalein and daidzein might serve as a method to improve the therapeutic efficacy of different flavonoids against A β , which might be crucial in developing those flavonoidsin treating Alzheimer's disease in the future.
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- 2013
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27. The membrane permeability of Astragali Radix-derived formononetin and calycosin is increased by Angelicae Sinensis Radix in Caco-2 cells: a synergistic action of an ancient herbal decoction Danggui Buxue Tang.
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Zheng KY, Choi RC, Guo AJ, Bi CW, Zhu KY, Du CY, Zhang ZX, Lau DT, Dong TT, and Tsim KW
- Subjects
- Angelica sinensis, Caco-2 Cells, Chromatography, Liquid, Coumaric Acids pharmacology, Drug Synergism, Humans, Permeability, Spectrometry, Mass, Electrospray Ionization, Tandem Mass Spectrometry, Time Factors, Drugs, Chinese Herbal metabolism, Drugs, Chinese Herbal pharmacology, Intestinal Absorption drug effects, Intestinal Mucosa drug effects, Intestinal Mucosa metabolism, Isoflavones metabolism
- Abstract
Danggui Buxue Tang (DBT), a herbal decoction contains Astragali Radix (AR) and Angelicae Sinensis Radix (ASR), has been used as a health food supplement in treating menopausal irregularity in women for more than 800 years in China. Several lines of evidence indicate that the synergistic actions of AR and ASR in this herbal decoction leading to a better pharmacological effect of DBT. Here, the role of different herbs in directing the transport of active ingredients of DBT was determined. A validated RRLC-QQQ-MS/MS method was applied to determinate the permeability of ingredients across the Caco-2 cell monolayer. AR-derived chemicals, including astragaloside IV, calycosin and formononetin, as well as ASR-derived chemicals, including ferulic acid and ligustilide, were determined by RRLC-QQQ-MS/MS. The pharmacokinetic results showed that the membrane permeabilities of calycosin and formononetin, two of the major flavonoids in AR, could be markedly increased in the presence of ASR extract: this induction effect could be mediated by ferulic acid deriving from ASR. In contrast, the extract of AR showed no effect on the chemical permeability. The current results suggested that the ingredients of ASR (such as ferulic acid) could enhance the membrane permeability of AR-derived formononetin and calycosin in cultured Caco-2 cells. The possibility of herb-drug synergy within DBT was proposed here., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2012
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28. Molecular identification of Diphyllobothrium latum and a brief review of diphyllobothriosis in China.
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Guo AJ, Liu K, Gong W, Luo XN, Yan HB, Zhao SB, Hu SN, and Jia WZ
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- Animals, China epidemiology, Diphyllobothriasis epidemiology, Diphyllobothrium genetics, Humans, Diphyllobothriasis parasitology, Diphyllobothrium classification
- Abstract
Two tapeworm specimens collected in northeast China in 2009 and 2011 were identified as Diphyllobothrium latum based on morphological criteria. Molecular methods were used to confirm their identity and analyze genetic variations compared with published data for this species. Species identity was confirmed by molecular characterization of the 18S rDNA partial sequence, complete sequences of internal transcribed spacers (ITSs) and 5.8S rDNA, and partial sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) and mitochondrial NADH dehydrogenase subunit 5 (nad5). PCR amplification and sequence analysis of 18S rDNA (1472 bp), ITS regions (1218 bp), cox1 (885 bp), and nad5 (1028 bp) revealed that these four sequences showed more than 99% identity to reference sequences for D. latum, confirming that this species is D. latum. To date, a total of 12 diphyllobothriosis cases have been documented in China. This study represents the first molecular characterization of D. latum in China, providing molecular evidence of human diphyllobothriosis in China.
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- 2012
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29. Changes in intracellular redox status influence multidrug resistance in gastric adenocarcinoma cells.
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Tai DJ, Jin WS, Wu CS, Si HW, Cao XD, Guo AJ, and Chang JC
- Abstract
Multidrug resistance (MDR) to chemotherapeutic agents is a major obstacle for the treatment of various types of cancers. The exact mechanism of MDR has not yet been fully clarified, although it has been frequently associated with the variation of intracellular redox status. The levels of intracellular glutathione (GSH) are considered to play a vital role in the regulation of the intracellular redox status. In our study, we investigated the effects of buthionine sulfoximine (BSO), an inhibitor of GSH biosynthesis, and NAC, a cysteine source for GSH synthesis, on sensitive gastric adenocarcinoma cells (SGC7901) and cisplatin-resistant SGC7901/DDP cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The two cell lines were pretreated with various non-toxic concentrations of BSO for 24 h and combined with fluorouracil (5-FU) or mitomycin (MMC) in the presence or absence of NAC before culturing further. After various treatments, the IC(50) values of MMC and 5-FU were calculated and intracellular GSH levels were measured using the glutathione reductase/5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) recycling assay without anticancer drug stimulation under the same microenvironments. The study demonstrated that BSO increased the sensitivity of the cells to chemotherapeutics while NAC exhibited the reverse effect, particularly in drug-resistant cells. It is, therefore, possible that changes in intracellular GSH levels affect the chemosensitivity of the resistant cells to a greater extent than that of their parent cells. This study indicates that variation in the intracellular redox status may be closely correlated with MDR and may provide a valuable basic strategy for anticancer therapy.
- Published
- 2012
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30. Kaempferol as a flavonoid induces osteoblastic differentiation via estrogen receptor signaling.
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Guo AJ, Choi RC, Zheng KY, Chen VP, Dong TT, Wang ZT, Vollmer G, Lau DT, and Tsim KW
- Abstract
Background: Flavonoids, a group of compounds mainly derived from vegetables and herbal medicines, chemically resemble estrogen and some have been used as estrogen substitutes. Kaempferol, a flavonol derived from the rhizome of Kaempferia galanga L., is a well-known phytoestrogen possessing osteogenic effects that is also found in a large number of plant foods.The herb K. galanga is a popular traditional aromatic medicinal plant that is widely used as food spice and in medicinal industries. In the present study, both the estrogenic and osteogenic properties of kaempferol are evaluated., Methods: Kaempferol was first evaluated for its estrogenic properties, including its effects on estrogen receptors. The osteogenic properties of kaempferol were further determined its induction effects on specific osteogenic enzymes and genes as well as the mineralization process in cultured rat osteoblasts., Results: Kaempferol activated the transcriptional activity of pERE-Luc (3.98 ± 0.31 folds at 50 μM) and induced estrogen receptor α (ERα) phosphorylation in cultured rat osteoblasts, and this ER activation was correlated with induction and associated with osteoblast differentiation biomarkers, including alkaline phosphatase activity and transcription of osteoblastic genes, e.g., type I collagen, osteonectin, osteocalcin, Runx2 and osterix. Kaempferol also promoted the mineralization process of osteoblasts (4.02 ± 0.41 folds at 50 μM). ER mediation of the kaempferol-induced effects was confirmed by pretreatment of the osteoblasts with an ER antagonist, ICI 182,780, which fully blocked the induction effect., Conclusion: Our results showed that kaempferol stimulates osteogenic differentiation of cultured osteoblasts by acting through the estrogen receptor signaling.
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- 2012
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31. Salidroside stimulates the accumulation of HIF-1α protein resulted in the induction of EPO expression: a signaling via blocking the degradation pathway in kidney and liver cells.
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Zheng KY, Zhang ZX, Guo AJ, Bi CW, Zhu KY, Xu SL, Zhan JY, Lau DT, Dong TT, Choi RC, and Tsim KW
- Subjects
- Basic Helix-Loop-Helix Transcription Factors metabolism, HEK293 Cells, Hep G2 Cells, Humans, Hypoxia-Inducible Factor 1, alpha Subunit biosynthesis, Kidney drug effects, Liver drug effects, Signal Transduction drug effects, Erythropoietin metabolism, Glucosides pharmacology, Hematinics pharmacology, Kidney metabolism, Liver metabolism, Phenols pharmacology
- Abstract
Rhodiolae Crenulatae Radix et Rhizoma (Rhodiola), the root and rhizome of Rhodiola crenulata (Hook. f. et Thoms.) H. Ohba, has been used as a traditional Chinese medicine (TCM) to increase the body resistance to mountain sickness in preventing hypoxia; however, the functional ingredient responsible for this adaptogenic effect has not been revealed. Here, we have identified salidroside, a glycoside predominantly found in Rhodiola, is the chemical in providing such anti-hypoxia effect. Cultured human embryonic kidney fibroblast (HEK293T) and human hepatocellular carcinoma (HepG2) were used to reveal the mechanism of this hematopoietic function mediated by salidroside. The application of salidroside in cultures induced the expression of erythropoietin (EPO) mRNA from its transcription regulatory element hypoxia response element (HRE), located on EPO gene. The application of salidroside stimulated the accumulation of hypoxia-inducible factor-1α (HIF-1α) protein, but not HIF-2α protein: the salidroside-induced HIF-1α protein was via the reduction of HIF-1α degradation but not the mRNA induction. The increased HIF-1α could account for the activation of EPO gene. These results supported the notion that hematopoietic function of Rhodiola was triggered, at least partially, by salidroside., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2012
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32. Isorhamnetin, A Flavonol Aglycone from Ginkgo biloba L., Induces Neuronal Differentiation of Cultured PC12 Cells: Potentiating the Effect of Nerve Growth Factor.
- Author
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Xu SL, Choi RC, Zhu KY, Leung KW, Guo AJ, Bi D, Xu H, Lau DT, Dong TT, and Tsim KW
- Abstract
Flavonoids, a group of compounds mainly derived from vegetables and herbal medicines, share a chemical resemblance to estrogen, and indeed some of which have been used as estrogen substitutes. In searching for possible functions of flavonoids, the neuroprotective effect in brain could lead to novel treatment, or prevention, for neurodegenerative diseases. Here, different subclasses of flavonoids were analyzed for its inductive role in neurite outgrowth of cultured PC12 cells. Amongst the tested flavonoids, a flavonol aglycone, isorhamnetin that was isolated mainly from the leaves of Ginkgo biloba L. showed robust induction in the expression of neurofilament, a protein marker for neurite outgrowth, of cultured PC12 cells. Although isorhamnetin by itself did not show significant inductive effect on neurite outgrowth of cultured PC12 cells, the application of isorhamnetin potentiated the nerve growth factor- (NGF-)induced neurite outgrowth. In parallel, the expression of neurofilaments was markedly increased in the cotreatment of NGF and isorhamnetin in the cultures. The identification of these neurite-promoting flavonoids could be very useful in finding potential drugs, or food supplements, for treating various neurodegenerative diseases, including Alzheimer's disease and depression.
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- 2012
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33. Molecular Assembly and Biosynthesis of Acetylcholinesterase in Brain and Muscle: the Roles of t-peptide, FHB Domain, and N-linked Glycosylation.
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Chen VP, Luk WK, Chan WK, Leung KW, Guo AJ, Chan GK, Xu SL, Choi RC, and Tsim KW
- Abstract
Acetylcholinesterase (AChE) is responsible for the hydrolysis of the neurotransmitter, acetylcholine, in the nervous system. The functional localization and oligomerization of AChE T variant are depending primarily on the association of their anchoring partners, either collagen tail (ColQ) or proline-rich membrane anchor (PRiMA). Complexes with ColQ represent the asymmetric forms (A(12)) in muscle, while complexes with PRiMA represent tetrameric globular forms (G(4)) mainly found in brain and muscle. Apart from these traditional molecular forms, a ColQ-linked asymmetric form and a PRiMA-linked globular form of hybrid cholinesterases (ChEs), having both AChE and BChE catalytic subunits, were revealed in chicken brain and muscle. The similarity of various molecular forms of AChE and BChE raises interesting question regarding to their possible relationship in enzyme assembly and localization. The focus of this review is to provide current findings about the biosynthesis of different forms of ChEs together with their anchoring proteins.
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- 2011
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34. The assembly of proline-rich membrane anchor (PRiMA)-linked acetylcholinesterase enzyme: glycosylation is required for enzymatic activity but not for oligomerization.
- Author
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Chen VP, Choi RC, Chan WK, Leung KW, Guo AJ, Chan GK, Luk WK, and Tsim KW
- Subjects
- Animals, Biocatalysis, Chickens, Enzyme Stability, GPI-Linked Proteins chemistry, GPI-Linked Proteins metabolism, Glycosylation, HEK293 Cells, Humans, Mice, Polysaccharides metabolism, Protein Binding, Protein Multimerization, Protein Structure, Quaternary, Protein Structure, Secondary, Protein Transport, Recombinant Proteins metabolism, Acetylcholinesterase chemistry, Acetylcholinesterase metabolism, Membrane Proteins metabolism, Nerve Tissue Proteins metabolism
- Abstract
Acetylcholinesterase (AChE) anchors onto cell membranes by a transmembrane protein PRiMA (proline-rich membrane anchor) as a tetrameric form in vertebrate brain. The assembly of AChE tetramer with PRiMA requires the C-terminal "t-peptide" in AChE catalytic subunit (AChE(T)). Although mature AChE is well known N-glycosylated, the role of glycosylation in forming the physiologically active PRiMA-linked AChE tetramer has not been studied. Here, several lines of evidence indicate that the N-linked glycosylation of AChE(T) plays a major role for acquisition of AChE full enzymatic activity but does not affect its oligomerization. The expression of the AChE(T) mutant, in which all N-glycosylation sites were deleted, together with PRiMA in HEK293T cells produced a glycan-depleted PRiMA-linked AChE tetramer but with a much higher K(m) value as compared with the wild type. This glycan-depleted enzyme was assembled in endoplasmic reticulum but was not transported to Golgi apparatus or plasma membrane.
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- 2011
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35. Genetic variation of the 8-kDa glycoprotein family from Echinococcus granulosus, Taenia multiceps and Taenia hydatigena.
- Author
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Jia WZ, Yan HB, Lou ZZ, Ni XW, Liu HX, Li HM, Guo AJ, and Fu BQ
- Subjects
- Amino Acid Sequence, Animals, DNA, Helminth genetics, Echinococcus granulosus genetics, Glycoproteins chemistry, Glycoproteins classification, Helminth Proteins chemistry, Helminth Proteins classification, Molecular Sequence Data, Phylogeny, Sequence Homology, Amino Acid, Taenia genetics, Echinococcus granulosus metabolism, Genetic Variation genetics, Glycoproteins genetics, Helminth Proteins genetics, Taenia metabolism
- Abstract
Background: Echinococcosis, coenurosis and cysticercosis are debilitating diseases which prevail in China. Immunological diagnosis of metacestodosis is important in disease control. The 8-kDa glycoproteins from taeniid cestodes have successfully been used for diagnosis of human cysticercosis in immunological assays. The aim of the present study was to investigate genetic variations and phylogenetic relationships of the 8-kDa proteins for evaluating the possibility of utilizing these proteins as diagnostic antigens for other metacestode infections., Methods: The genes and complementary DNAs (cDNAs) encoding the 8-kDa proteins from Echinococcus (E.) granulosus, Taenia (T.) multiceps and T. hydatigena were amplified using PCR method. Their amplicons were cloned into the vector pMD18 and the positive clones were sequenced. Sequence data were analyzed with the SeqMan program, and sequence homology searches were performed using the BLAST program. Alignments were conducted using the ClustalX program, and the phylogenetic analyses were performed with the Protein Sequences Program and the Puzzle Program using the Neighbor-joining method., Results: Fifteen, 18 and 22 different genomic DNA sequences were identified as members of the 8-kDa protein gene family from E. granulosus, T. multiceps and T. hydatigena, respectively. Eight, four and six different cDNA clones respectively from E. granulosus, T. multiceps and T. hydatigena were characterized. Analysis of these sequences revealed 54 unique 8-kDa protein sequences. Phylogenetic trees demonstrated that the taeniid 8-kDa proteins are clustered into eight clades at least: Ts18, Ts14, TsRS1, TsRS2, T8kDa-1, T8kDa-2, T8kDa-3 and T8kDa-4., Conclusion: We found that the gene family encoding for the taeniid 8-kDa antigens is comprised of many members with high diversity, which will provide molecular evidence for cross-reaction or specific reaction among metacestode infections and may contribute to the development of promising immunological methods for diagnosis of metacestodosis.
- Published
- 2011
36. Baicalin, a flavone, induces the differentiation of cultured osteoblasts: an action via the Wnt/beta-catenin signaling pathway.
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Guo AJ, Choi RC, Cheung AW, Chen VP, Xu SL, Dong TT, Chen JJ, and Tsim KW
- Subjects
- Active Transport, Cell Nucleus drug effects, Active Transport, Cell Nucleus physiology, Animals, Antigens, Differentiation biosynthesis, Calcification, Physiologic drug effects, Calcification, Physiologic physiology, Cell Differentiation physiology, Cells, Cultured, Female, Glycogen Synthase Kinase 3 antagonists & inhibitors, Glycogen Synthase Kinase 3 metabolism, Glycogen Synthase Kinase 3 beta, Humans, Intercellular Signaling Peptides and Proteins metabolism, Osteoblasts cytology, Osteoporosis, Postmenopausal metabolism, Osteoporosis, Postmenopausal prevention & control, Phosphorylation drug effects, Phosphorylation physiology, RNA, Messenger biosynthesis, Rats, Transcription, Genetic drug effects, Transcription, Genetic physiology, Wnt Signaling Pathway physiology, Cell Differentiation drug effects, Cell Nucleus metabolism, Enzyme Inhibitors pharmacology, Flavonoids pharmacology, Osteoblasts metabolism, Wnt Proteins metabolism, Wnt Signaling Pathway drug effects, beta Catenin metabolism
- Abstract
Flavonoids, a group of natural compounds found in a variety of vegetables and herbal medicines, have been intensively reported on regarding their estrogen-like activities and particularly their ability to affect bone metabolism. Here, different subclasses of flavonoids were screened for their osteogenic properties by measuring alkaline phosphatase activity in cultured rat osteoblasts. The flavone baicalin derived mainly from the roots of Scutellaria baicalensis showed the strongest induction of alkaline phosphatase activity. In cultured osteoblasts, application of baicalin increased significantly the osteoblastic mineralization and the levels of mRNAs encoding the bone differentiation markers, including osteonectin, osteocalcin, and collagen type 1α1. Interestingly, the osteogenic effect of baicalin was not mediated by its estrogenic activity. In contrast, baicalin promoted osteoblastic differentiation via the activation of the Wnt/β-catenin signaling pathway; the activation resulted in the phosphorylation of glycogen synthase kinase 3β and, subsequently, induced the nuclear accumulation of the β-catenin, leading to the transcription activation of Wnt-targeted genes for osteogenesis. The baicalin-induced osteogenic effects were fully abolished by DKK-1, a blocker of Wnt/β-catenin receptor. Moreover, baicalin also enhanced the mRNA expression of osteoprotegerin, which could regulate indirectly the activation of osteoclasts. Taken together, our results suggested that baicalin could act via Wnt/β-catenin signaling to promote osteoblastic differentiation. The osteogenic flavonoids could be very useful in finding potential drugs, or food supplements, for treating post-menopausal osteoporosis.
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- 2011
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37. The extract of Rhodiolae Crenulatae Radix et Rhizoma induces the accumulation of HIF-1α via blocking the degradation pathway in cultured kidney fibroblasts.
- Author
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Zheng KY, Guo AJ, Bi CW, Zhu KY, Chan GK, Fu Q, Xu SL, Zhan JY, Lau DT, Dong TT, Choi RC, and Tsim KW
- Subjects
- Cells, Cultured, Deferoxamine pharmacology, Dose-Response Relationship, Drug, Drugs, Chinese Herbal chemistry, Erythropoietin genetics, Fibroblasts drug effects, Fibroblasts metabolism, Humans, Hypoxia immunology, Hypoxia metabolism, Hypoxia-Inducible Factor 1, alpha Subunit genetics, Kidney cytology, Kidney metabolism, Mixed Function Oxygenases antagonists & inhibitors, Plant Roots chemistry, RNA, Messenger metabolism, Recombinant Fusion Proteins, Response Elements genetics, Rhizome chemistry, Siderophores pharmacology, Transcriptional Activation, Drugs, Chinese Herbal pharmacology, Erythropoietin metabolism, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Kidney drug effects, Rhodiola chemistry
- Abstract
Rhodiolae Crenulatae Radix et Rhizoma (Rhodiola), the root and rhizome of Rhodiola crenulata (Hook. f. et Thoms.) H. Ohba, has been used as a traditional Chinese medicine (TCM) to increase the body resistance against hypoxia in mountain sickness. The mechanism of this adaptogenic property deriving from Rhodiola, however, has not been revealed. Erythropoietin (EPO) is an erythrocyte-specific hematopoietic hormone that increases the production of red blood cells: this hormone is a crucial factor in regulating the body balance in responding to hypoxia. In cultured kidney fibroblasts (HEK293T), application of water extract deriving from Rhodiola induced the expression of EPO both in mRNA and protein levels. The activation of the Hypoxia Response Element (HRE) located on the promoter region of the EPO gene is one of the mechanisms accounting for transcriptional activation. In addition, the Rhodiola-induced EPO expression was triggered by an increase of hypoxia-inducible factor-1 α (HIF-1 α) protein, via the reduction of HIF-1 α degradation but not the induction of HIF-1 α mRNA. Moreover, the same EPO induction effect by Rhodiola was also observed in cultured liver cells since liver is another vital organ to provide EPO regulation apart from the kidney. These results therefore elucidate one of the molecular mechanisms of this herb in mediating the anti-hypoxia function., (© Georg Thieme Verlag KG Stuttgart · New York.)
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- 2011
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38. Flavonoids from Radix Astragali induce the expression of erythropoietin in cultured cells: a signaling mediated via the accumulation of hypoxia-inducible factor-1α.
- Author
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Zheng KY, Choi RC, Cheung AW, Guo AJ, Bi CW, Zhu KY, Fu Q, Du Y, Zhang WL, Zhan JY, Duan R, Lau DT, Dong TT, and Tsim KW
- Subjects
- Astragalus Plant chemistry, Astragalus propinquus, Cell Line, HEK293 Cells, Humans, Hypoxia-Inducible Factor 1, alpha Subunit analysis, Hypoxia-Inducible Factor 1, alpha Subunit genetics, RNA, Messenger analysis, Transfection, Drugs, Chinese Herbal chemistry, Erythropoietin genetics, Flavonoids pharmacology, Gene Expression drug effects, Hypoxia-Inducible Factor 1, alpha Subunit physiology, Signal Transduction physiology
- Abstract
Radix Astragali (RA) is commonly used as a health food supplement to reinforce the body vital energy. Flavonoids, including formononetin, ononin, calycosin, and calycosin-7-O-β-d-glucoside, are considered to be the major active ingredients within RA. Here, we provided different lines of evidence that the RA flavonoids stimulated the expression of erythropoietin (EPO), the central regulator of red blood cell mass, in cultured human embryonic kidney fibroblasts (HEK293T). A plasmid containing hypoxia response element (HRE), a critical regulator for EPO transcription, was tagged upstream of a firefly luciferase gene, namely, pHRE-Luc, which was being transfected into fibroblasts. The application of RA flavonoids onto the transfected cells induced the transcriptional activity of HRE. To account for the transcriptional activation after the treatment of flavonoids, the expression of hypoxia-inducible factor-1α (HIF-1α) was markedly increased: The increase was in both mRNA and protein levels. In addition, the degradation of HIF-1α was reduced under the effect of flavonoids. The regulation of HIF-1α therefore could account for the activation of EPO expression mediated by the RA flavonoids. The current results therefore reveal the function of this herb in enhancing hematopoietic functions.
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- 2011
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39. The expression of erythropoietin triggered by danggui buxue tang, a Chinese herbal decoction prepared from radix Astragali and radix Angelicae Sinensis, is mediated by the hypoxia-inducible factor in cultured HEK293T cells.
- Author
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Zheng KY, Choi RC, Xie HQ, Cheung AW, Guo AJ, Leung KW, Chen VP, Bi CW, Zhu KY, Chan GK, Fu Q, Lau DT, Dong TT, Zhao KJ, and Tsim KW
- Subjects
- Angelica sinensis, Astragalus Plant chemistry, Astragalus propinquus, Blotting, Western, Cell Culture Techniques, Cell Line, Drugs, Chinese Herbal isolation & purification, Erythropoietin genetics, Humans, Hypoxia-Inducible Factor 1, alpha Subunit biosynthesis, Hypoxia-Inducible Factor 1, alpha Subunit genetics, Luciferases genetics, Response Elements genetics, Reverse Transcriptase Polymerase Chain Reaction, Transfection, Drugs, Chinese Herbal chemistry, Drugs, Chinese Herbal pharmacology, Erythropoietin biosynthesis, Hypoxia-Inducible Factor 1, alpha Subunit physiology
- Abstract
Ethnopharmacological Evidence: Danggui buxue tang (DBT), a Chinese medicinal decoction that is being commonly used as hematopoietic medicine to treating woman menopausal irregularity, contains two herbs: radix Astragali and radix Angelicae Sinensis. Pharmacological results indicate that DBT can stimulate the production of erythropoietin (EPO), a specific hematopoietic growth factor, in cultured cells., Aim of the Study: In order to reveal the mechanism of DBT's hematopoietic function, this study investigated the activity of the DBT-induced EPO expression and the upstream regulatory cascade of EPO via hypoxia-induced signaling in cultured kidney fibroblasts (HEK293T)., Materials and Methods: DBT-induced mRNA expressions were revealed by real-time PCR, while the change of protein expressions were analyzed by Western blotting. For the analysis of hypoxia-dependent signaling, a luciferase reporter was used to report the transcriptional activity of hypoxia response element (HRE)., Results: The plasmid containing HRE, being transfected into HEK293T, was highly responsive to the challenge of DBT application. To account for the transcriptional activation of HRE, DBT treatment was shown to increase the mRNA and protein expressions of hypoxia-inducible factor-1α (HIF-1α). In addition, the activation of Raf/MEK/ERK signaling pathway by DBT could also enhance the translation of HIF-1α, suggesting the dual actions of DBT in stimulating the EPO expression in kidney cells., Conclusion: Our study indicates that HIF pathway plays an essential role in directing DBT-induced EPO expression in kidney. These results provide one of the molecular mechanisms of this ancient herbal decoction for its hematopoietic function., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)
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- 2010
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40. PRiMA directs a restricted localization of tetrameric AChE at synapses.
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Xie HQ, Leung KW, Chen VP, Chan GK, Xu SL, Guo AJ, Zhu KY, Zheng KY, Bi CW, Zhan JY, Chan WK, Choi RC, and Tsim KW
- Subjects
- Amino Acid Sequence, Animals, Humans, Membrane Proteins chemistry, Molecular Sequence Data, Nerve Tissue Proteins chemistry, Protein Structure, Quaternary, Protein Transport, Synapses enzymology, Acetylcholinesterase chemistry, Acetylcholinesterase metabolism, Membrane Proteins metabolism, Nerve Tissue Proteins metabolism, Protein Multimerization, Synapses metabolism
- Abstract
Acetylcholinesterase (AChE), a highly polymorphic enzyme with various splicing variants and molecular isoforms, plays an essential role in the cholinergic neurotransmission by hydrolyzing acetylcholine into choline and acetate. The AChE(T) variant is expressed in the brain and muscle: this subunit forms non-amphiphilic tetramers with a collagen tail (ColQ) as asymmetric AChE (A(12) AChE) in muscle, and amphiphilic tetramers with a proline-rich membrane anchor (PRiMA) as globular AChE (G(4) AChE) in the brain and muscle. During the brain development, the expression of amphiphilic G(4) AChE is up regulated and becomes the predominant form of AChE there. This up-regulation of G(4) AChE can be attributed to the increased expressions of both AChE(T) and PRiMA. A significant portion of this membrane-bound G(4) AChE is localized at the membrane rafts of the cell membranes derived from the brain. This raft association could be directed by PRiMA via its CRAC (cholesterol recognition/interaction amino acid consensus) motif and C-terminus. In cultured cortical neurons and muscles, the PRiMA-linked AChE was clustered and partially co-localized with synaptic proteins. The restricted localizations suggest that the raft association of PRiMA-linked AChE could account for its synaptic localization and function., (Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.)
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- 2010
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41. Galangin, a flavonol derived from Rhizoma Alpiniae Officinarum, inhibits acetylcholinesterase activity in vitro.
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Guo AJ, Xie HQ, Choi RC, Zheng KY, Bi CW, Xu SL, Dong TT, and Tsim KW
- Subjects
- Animals, Cholinesterase Inhibitors chemistry, Drug Evaluation, Preclinical, Drugs, Chinese Herbal chemistry, Drugs, Chinese Herbal isolation & purification, Drugs, Chinese Herbal pharmacology, Flavonoids chemistry, Rats, Acetylcholinesterase metabolism, Alpinia chemistry, Cholinesterase Inhibitors isolation & purification, Cholinesterase Inhibitors pharmacology, Flavonoids isolation & purification, Flavonoids pharmacology, Rhizome chemistry
- Abstract
Acetylcholinesterase (AChE) inhibitors are widely used for the treatment of Alzheimer's disease (AD). Several AChE inhibitors, e.g. rivastigmine, galantamine and huperzine are originating from plants, suggesting that herbs could potentially serve as sources for novel AChE inhibitors. Here, we searched potential AChE inhibitors from flavonoids, a group of naturally occurring compounds in plants or traditional Chinese medicines (TCM). Twenty-one flavonoids, covered different subclasses, were tested for their potential function in inhibiting AChE activity from the brain in vitro. Among all the tested flavonoids, galangin, a flavonol isolated from Rhizoma Alpiniae Officinarum, the rhizomes of Alpiniae officinarum (Hance.) showed an inhibitory effect on AChE activity with the highest inhibition by over 55% and an IC(50) of 120 microM and an enzyme-flavonoid inhibition constant (K(i)) of 74 microM. The results suggest that flavonoids could be potential candidates for further development of new drugs against AD., (Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.)
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- 2010
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42. Complete mitochondrial genomes of Taenia multiceps, T. hydatigena and T. pisiformis: additional molecular markers for a tapeworm genus of human and animal health significance.
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Jia WZ, Yan HB, Guo AJ, Zhu XQ, Wang YC, Shi WG, Chen HT, Zhan F, Zhang SH, Fu BQ, Littlewood DT, and Cai XP
- Subjects
- Animals, Genetic Variation, Humans, Phylogeny, RNA, Transfer genetics, Genome, Mitochondrial, Taenia classification, Taenia genetics
- Abstract
Background: Mitochondrial genomes provide a rich source of molecular variation of proven and widespread utility in molecular ecology, population genetics and evolutionary biology. The tapeworm genus Taenia includes a diversity of tapeworm parasites of significant human and veterinary importance. Here we add complete sequences of the mt genomes of T. multiceps, T. hydatigena and T. pisiformis, to a data set of 4 published mtDNAs in the same genus. Seven complete mt genomes of Taenia species are used to compare and contrast variation within and between genomes in the genus, to estimate a phylogeny for the genus, and to develop novel molecular markers as part of an extended mitochondrial toolkit., Results: The complete circular mtDNAs of T. multiceps, T. hydatigena and T. pisiformis were 13,693, 13,492 and 13,387 bp in size respectively, comprising the usual complement of flatworm genes. Start and stop codons of protein coding genes included those found commonly amongst other platyhelminth mt genomes, but the much rarer initiation codon GTT was inferred for the gene atp6 in T. pisiformis. Phylogenetic analysis of mtDNAs offered novel estimates of the interrelationships of Taenia. Sliding window analyses showed nad6, nad5, atp6, nad3 and nad2 are amongst the most variable of genes per unit length, with the highest peaks in nucleotide diversity found in nad5. New primer pairs capable of amplifying fragments of variable DNA in nad1, rrnS and nad5 genes were designed in silico and tested as possible alternatives to existing mitochondrial markers for Taenia., Conclusions: With the availability of complete mtDNAs of 7 Taenia species, we have shown that analysis of amino acids provides a robust estimate of phylogeny for the genus that differs markedly from morphological estimates or those using partial genes; with implications for understanding the evolutionary radiation of important Taenia. Full alignment of the nucleotides of Taenia mtDNAs and sliding window analysis suggests numerous alternative gene regions are likely to capture greater nucleotide variation than those currently pursued as molecular markers. New PCR primers developed from a comparative mitogenomic analysis of Taenia species, extend the use of mitochondrial markers for molecular ecology, population genetics and diagnostics.
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- 2010
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43. Effects of ternary complexes of copper with salicylaldehyde-amino acid Schiff base coordination compounds on the proliferation of BGC823 cells.
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Guo AJ, Xu XS, Hu YH, Wang MZ, and Tan X
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- Amino Acids chemistry, Antineoplastic Agents chemical synthesis, Antineoplastic Agents pharmacology, Apoptosis drug effects, Cell Cycle drug effects, Cell Line, Tumor, Coordination Complexes chemical synthesis, Humans, Inhibitory Concentration 50, Stomach Neoplasms metabolism, Tumor Suppressor Protein p53 metabolism, Aldehydes chemistry, Cell Proliferation drug effects, Coordination Complexes pharmacology, Copper chemistry, Schiff Bases chemistry, Stomach Neoplasms pathology
- Abstract
Background and Objective: The basic structure of salicylaldehyde-amino acid Schiff base compounds includes a C=N chemical bond. These compounds show significant antitumor activities in vitro when combined with a metal ion. This study investigated the effects and possible mechanisms of four salicylaldehyde-amino acid Schiff base copper ternary coordination compounds on the proliferation of human gastric cancer cell line BGC823., Methods: The BGC823 cells were treated with the four compounds (6B, 7B, 6P, and 7P). Cell proliferation was detected by MTT assay. Apoptosis and changes in the cell cycle were analyzed by flow cytometry. DNA damage was observed using a DNA ladder assay. The expression of p53 protein was determined by immunocytochemistry., Results: The proliferation of BGC823 cells was significantly inhibited by the four compounds and the effect was concentration-dependent. The half maximal inhibitory concentration (IC50) of 6B, 7B, 6P, and 7P for BGC823 cells were 18.10, 27.50, 3.61, and 3.45 micromol/L, respectively. Flow cytometry showed the four drugs induced apoptosis in BGC823 cells, which was confirmed by DNA ladder experiments. Flow cytometry also detected changed phases in the cell cycle from treatment with the compounds. The percent of cells in the G(0)/G(1) phase decreased and that of cells in the G1/S and G(2)/M phases increased, indicating that S-and G2-phase blockages exist. As shown by immunocytochemistry, the expression of p53 decreased in BGC823 cells treated with the four drugs, indicating the involvement of the p53 pathway to BGC823 cell apoptosis., Conclusions: The four compounds showed significant activities on restraining proliferation of BGC823 cells in vitro, induced apoptosis, and caused changes in the cell cycle. This may be related to the downregulation of p53.
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- 2010
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44. Ligustilide suppresses the biological properties of Danggui Buxue Tang: a Chinese herbal decoction composed of radix astragali and radix angelica sinensis.
- Author
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Zheng YZ, Choi RC, Li J, Xie HQ, Cheung AW, Duan R, Guo AJ, Zhu JT, Chen VP, Bi CW, Zhu Y, Lau DD, Dong TT, Lau BW, and Tsim KW
- Subjects
- 4-Butyrolactone pharmacology, Angelica sinensis, Astragalus propinquus, Cell Line, Tumor, Cell Proliferation drug effects, Chemistry, Pharmaceutical, Drug Antagonism, Humans, Isoflavones isolation & purification, Medicine, Chinese Traditional, Polysaccharides isolation & purification, Saponins isolation & purification, Triterpenes isolation & purification, 4-Butyrolactone analogs & derivatives, Drugs, Chinese Herbal chemistry
- Abstract
Danggui Buxue Tang (DBT), a herbal decoction composed of Radix Astragali (RA) and Radix Angelica sinensis (RAS), has been used for treating menopausal irregularity in women for more than 800 years in China. According to the old tradition, RAS had to be processed with yellow wine before DBT preparation, which markedly reduced the amount of ligustilide in RAS and DBT, as well as enhanced the bioactivities of DBT. Here, we hypothesized that ligustilide would be an ingredient that possessed suppressive effects on DBT's functions. In the presence of ligustilide, the amount of astragaloside IV, calycosin, formononetin, and total polysaccharides extracted from RA were decreased. An increase of ligustilide caused a decrease of DBT's osteogenic activity in stimulating proliferation and differentiation of cultured bone cells. In addition, in the presence of a high level of ligustilide, DBT caused a side effect inducing the proliferation of breast MCF-7 cells. The current results strongly suggest that ligustilide is a negative regulator that hinders DBT to achieve its biological efficacy, which supports the traditional practice of preparing DBT using the ethanol-treated RAS., ((c) Georg Thieme Verlag KG Stuttgart . New York.)
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- 2010
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45. Expression and Localization of PRiMA-linked globular form acetylcholinesterase in vertebrate neuromuscular junctions.
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Tsim KW, Leung KW, Mok KW, Chen VP, Zhu KY, Zhu JT, Guo AJ, Bi CW, Zheng KY, Lau DT, Xie HQ, and Choi RC
- Subjects
- Animals, Cell Differentiation genetics, Motor Neurons enzymology, Motor Neurons ultrastructure, Muscle, Skeletal enzymology, Muscle, Skeletal growth & development, Muscle, Skeletal innervation, Neuromuscular Junction growth & development, Neuromuscular Junction ultrastructure, Presynaptic Terminals enzymology, Presynaptic Terminals ultrastructure, Protein Conformation, RNA, Messenger metabolism, Rats, Receptor Aggregation physiology, Spinal Cord growth & development, Spinal Cord ultrastructure, Synaptic Membranes enzymology, Synaptic Membranes ultrastructure, Synaptic Transmission physiology, Up-Regulation genetics, Acetylcholinesterase chemistry, Acetylcholinesterase metabolism, Membrane Proteins genetics, Nerve Tissue Proteins genetics, Neuromuscular Junction enzymology, Spinal Cord enzymology
- Abstract
Acetylcholinesterase (AChE) is well known to process different molecular forms via the distinct interacting partners. Proline-rich membrane anchor (PRiMA)-linked tetrameric globular AChE (G4 AChE) is mainly found in the vertebrate brain; however, recent studies from our laboratory have suggested its existence at neuromuscular junctions (nmjs). Both muscle and motor neuron express AChE at the nmjs. In muscle, the expression of PRiMA-linked AChE is down-regulated during myogenic differentiation and by motor neuron innervation. As compared with muscle, spinal cord possessed higher total AChE activity and contained PRiMA-linked AChE forms. The spinal cord expression of this form increased during development. More importantly, PRiMA-linked G4 AChE identified as aggregates localized at nmjs. These findings suggest that the restricted localization of PRiMA-linked G4 AChE at the nmjs could be contributed by the pre-synaptic motor neuron and/or the post-synaptic muscle fiber.
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- 2010
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46. A new variant of proline-rich membrane anchor (PRiMA) of acetylcholinesterase in chicken: expression in different muscle fiber types.
- Author
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Mok MK, Leung KW, Xie HQ, Guo AJ, Chen VP, Zhu JT, Choi RC, and Tsim KW
- Subjects
- Alternative Splicing, Amino Acid Sequence, Animals, Chickens, Computational Biology, Membrane Proteins genetics, Molecular Sequence Data, Protein Isoforms biosynthesis, Protein Isoforms genetics, Protein Multimerization, Protein Structure, Tertiary, Reverse Transcriptase Polymerase Chain Reaction, Acetylcholinesterase metabolism, Membrane Proteins biosynthesis, Muscle Fibers, Fast-Twitch metabolism, Muscle Fibers, Slow-Twitch metabolism
- Abstract
Proline-rich membrane anchor (PRiMA) is a molecule to organize acetylcholinesterase (AChE) into tetrameric globular form (G(4)) that anchors onto the plasma membrane in brain and muscle. In mammal, PRiMA is encoded by a single gene with two splicing variants, PRiMA I and PRiMA II: PRiMA II is different to PRiMA I by its absence of a C-terminal cytoplasmic domain. The existence of these isoforms has not been revealed in avian specie. By using RT-PCR and bioinformatic analyses, two splicing variants of PRiMA were identified in chicken cerebrum. One variant contains very similar domains as compared to mammalian PRiMA I. The other variant, named as PRiMA II, has a very distinct cytoplasmic C-terminus of having 26 amino acids. Both forms of chicken PRiMA were able to organize the formation of G(4) AChE when that was over expressed together with AChE(T) subunit in cultured cells. The level of PRiMA mRNA, mainly PRiMA I, was higher in slow-twitch muscle than that of in fast-twitch muscle of chicken. This finding suggests that the muscle fiber type-specific expression of G(4) AChE in chicken could be a result of the different expression pattern of PRiMA in fast- and slow-twitch muscles.
- Published
- 2009
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47. Hibifolin, a flavonol glycoside, prevents beta-amyloid-induced neurotoxicity in cultured cortical neurons.
- Author
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Zhu JT, Choi RC, Xie HQ, Zheng KY, Guo AJ, Bi CW, Lau DT, Li J, Dong TT, Lau BW, Chen JJ, and Tsim KW
- Subjects
- Amyloid beta-Peptides toxicity, Animals, Apoptosis drug effects, Calcium metabolism, Cell Survival drug effects, Cells, Cultured, Cerebral Cortex cytology, Neurons cytology, Peptide Fragments toxicity, Proto-Oncogene Proteins c-akt physiology, Rats, Signal Transduction, Amyloid beta-Peptides physiology, Flavonoids pharmacology, Neurons drug effects, Neuroprotective Agents pharmacology, Peptide Fragments physiology
- Abstract
The toxicity of aggregated beta-amyloid (A beta) has been implicated as a critical cause in the development of Alzheimer's disease (AD). Hibifolin, a flavonol glycoside derived from herbal plants, possessed a strong protective activity against cell death induced by aggregated A beta. Application of hibifolin in primary cortical neurons prevented the A beta-induced cell death in a dose-dependent manner. In cultured cortical neurons, the pre-treatment of hibifolin abolished A beta-induced Ca(2+) mobilization, and also reduced A beta-induced caspase-3 and caspase-7 activation. Moreover, DNA fragmentation induced by A beta could be suppressed by hibifolin. In addition to such protection mechanisms, hibifolin was able to induce Akt phosphorylation in cortical neurons, which could be another explanation for the neuroprotection activity. These results therefore provided the first evidence that hibifolin protected neurons against A beta-induced apoptosis and stimulated Akt activation, which would be useful in developing potential drugs or food supplements for treating AD.
- Published
- 2009
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48. Stimulation of Apolipoprotein A-IV expression in Caco-2/TC7 enterocytes and reduction of triglyceride formation in 3T3-L1 adipocytes by potential anti-obesity Chinese herbal medicines.
- Author
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Guo AJ, Choi RC, Cheung AW, Li J, Chen IX, Dong TT, Tsim KW, and Lau BW
- Abstract
Background: Chinese medicine has been proposed as a novel strategy for the prevention of metabolic disorders such as obesity. The present study tested 17 Chinese medicinal herbs were tested for their potential anti-obesity effects., Methods: The herbs were evaluated in terms of their abilities to stimulate the transcription of Apolipoprotein A-IV (ApoA-IV) in cultured Caco-2/TC7 enterocytes. The herbs that showed stimulating effects on ApoA-IV transcription were further evaluated in terms of their abilities to reduce the formation of triglyceride in differentiated 3T3-L1 adipocytes., Results: ApoA-IV transcription was stimulated by Rhizoma Alismatis and Radix Angelica Sinensis in a dose- and time-dependent manner in cultured Caco-2/TC7 cells. Moreover, these two herbs reduced the amount of triglyceride in differentiated 3T3-L1 adipocytes., Conclusion: The results suggest that Rhizoma Alistmatis and Radix Angelica Sinensis may have potential anti-obesity effects as they stimulate ApoA-IV transcription and reduce triglyceride formation.
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- 2009
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49. Quality evaluation of Rhizoma Belamcandae (Belamcanda chinensis (L.) DC.) by using high-performance liquid chromatography coupled with diode array detector and mass spectrometry.
- Author
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Li J, Li WZ, Huang W, Cheung AW, Bi CW, Duan R, Guo AJ, Dong TT, and Tsim KW
- Subjects
- Calibration, Chromatography, High Pressure Liquid, Mass Spectrometry, Phenols chemistry, Quality Control, Reproducibility of Results, Sensitivity and Specificity, Drugs, Chinese Herbal chemistry, Drugs, Chinese Herbal standards, Iridaceae chemistry, Phenols analysis
- Abstract
A high-performance liquid chromatography coupled with diode array detector and mass spectrometry (HPLC-DAD-MS) method was developed to evaluate the quality of Rhizoma Belamcandae (Belamcanda chinensis (L.) DC.) through establishing chromatographic fingerprint and simultaneous determination of seven phenolic compounds. The analysis was achieved on an Alltima C(18) analytical column (250 mm x 4.6 mm i.d. 5 microm) using linear gradient elution of acetonitrile-0.1% trifluoroacetic acid. The correlation coefficients of similarity were determined from the HPLC fingerprints, and they shared a close similarity. By using an online APCI-MS/MS, twenty phenols were identified. In addition, seven of these phenols including mangiferin, 7-O-methylmangiferin, tectoridin, resveratrol, tectorigenin, irigenin and irisflorentin were quantified by the validated HPLC-DAD method. These phenols are considered to be major constituents in Rhizoma Belamcandae, and are generally regarded as the index for quality assessment of this herb. This developed method by having a combination of chromatographic fingerprint and quantification analysis could be applied to the quality control of Rhizoma Belamcandae.
- Published
- 2009
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50. Metabolic changes in schizophrenia and human brain evolution.
- Author
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Khaitovich P, Lockstone HE, Wayland MT, Tsang TM, Jayatilaka SD, Guo AJ, Zhou J, Somel M, Harris LW, Holmes E, Pääbo S, and Bahn S
- Subjects
- Adult, Aged, Animals, Biological Evolution, Cognition physiology, Energy Metabolism genetics, Female, Gene Expression, Gene Expression Profiling, Humans, Macaca mulatta genetics, Macaca mulatta metabolism, Male, Middle Aged, Nuclear Magnetic Resonance, Biomolecular, Oligonucleotide Array Sequence Analysis, Pan troglodytes genetics, Pan troglodytes metabolism, RNA, Messenger chemistry, RNA, Messenger metabolism, Schizophrenia genetics, Brain metabolism, Schizophrenia metabolism
- Abstract
Background: Despite decades of research, the molecular changes responsible for the evolution of human cognitive abilities remain unknown. Comparative evolutionary studies provide detailed information about DNA sequence and mRNA expression differences between humans and other primates but, in the absence of other information, it has proved very difficult to identify molecular pathways relevant to human cognition., Results: Here, we compare changes in gene expression and metabolite concentrations in the human brain and compare them to the changes seen in a disorder known to affect human cognitive abilities, schizophrenia. We find that both genes and metabolites relating to energy metabolism and energy-expensive brain functions are altered in schizophrenia and, at the same time, appear to have changed rapidly during recent human evolution, probably as a result of positive selection., Conclusion: Our findings, along with several previous studies, suggest that the evolution of human cognitive abilities was accompanied by adaptive changes in brain metabolism, potentially pushing the human brain to the limit of its metabolic capabilities.
- Published
- 2008
- Full Text
- View/download PDF
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