Publications by authors named "Yufang Sun"

27 Publications

  • Page 1 of 1

Neuromedin B receptor stimulation of Cav3.2 T-type Ca channels in primary sensory neurons mediates peripheral pain hypersensitivity.

Theranostics 2021 9;11(19):9342-9357. Epub 2021 Sep 9.

Department of Physiology and Neurobiology & Centre for Ion Channelopathy, Medical College of Soochow University, Suzhou 215123, China.

Neuromedin B (Nmb) is implicated in the regulation of nociception of sensory neurons. However, the underlying cellular and molecular mechanisms remain unknown. Using patch clamp recording, western blot analysis, immunofluorescent labelling, enzyme-linked immunosorbent assays, adenovirus-mediated shRNA knockdown and animal behaviour tests, we studied the effects of Nmb on the sensory neuronal excitability and peripheral pain sensitivity mediated by Cav3.2 T-type channels. Nmb reversibly and concentration-dependently increased T-type channel currents ( ) in small-sized trigeminal ganglion (TG) neurons through the activation of neuromedin B receptor (NmbR). This NmbR-mediated response was G protein-coupled, but independent of protein kinase C activity. Either intracellular application of the QEHA peptide or shRNA-mediated knockdown of G abolished the NmbR-induced response. Inhibition of protein kinase A (PKA) or AMP-activated protein kinase (AMPK) completely abolished the Nmb-induced response. Analysis of phospho-AMPK (-AMPK) revealed that Nmb significantly activated AMPK, while AMPK inhibition prevented the Nmb-induced increase in PKA activity. In a heterologous expression system, activation of NmbR significantly enhanced the Cav3.2 channel currents, while the Cav3.1 and Cav3.3 channel currents remained unaffected. Nmb induced TG neuronal hyperexcitability and concomitantly induced mechanical and thermal hypersensitivity, both of which were attenuated by T-type channel blockade. Moreover, blockade of NmbR signalling prevented mechanical hypersensitivity in a mouse model of complete Freund's adjuvant-induced inflammatory pain, and this effect was attenuated by siRNA knockdown of Cav3.2. Our study reveals a novel mechanism by which NmbR stimulates Cav3.2 channels through a G-dependent AMPK/PKA pathway. In mouse models, this mechanism appears to drive the hyperexcitability of TG neurons and induce pain hypersensitivity.
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http://dx.doi.org/10.7150/thno.62255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8490515PMC
September 2021

Pretreating poplar cuttings with low nitrogen ameliorates salt stress responses by increasing stored carbohydrates and priming stress signaling pathways.

Ecotoxicol Environ Saf 2021 Dec 21;225:112801. Epub 2021 Sep 21.

School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China. Electronic address:

Soil salinity is a widespread stress in semi-arid forests worldwide, but how to manage nitrogen (N) nutrition to improve plant saline tolerance remains unclear. Here, the cuttings of a widely distributed poplar from central Asia, Populus russikki Jabl., were exposed to either normal or low nitrogen (LN) concentrations for two weeks in semi-controlled greenhouse, and then they were added with moderate salt solution or not for another two weeks to evaluate their physiological, biochemical, metabolites and transcriptomic profile changes. LN-pretreating alleviated the toxicity caused by the subsequent salt stress in the poplar plants, demonstrated by a significant reduction in the influx of Na and Cl and improvement of the K/Na ratio. The other salt-stressed traits were also ameliarated, indicated by the variations of chlorophyll content, PSII photochemical activity and lipid peroxidation. Stress alleviation resulted from two different processes. First, LN pretreatment caused a significant increase of non-structural carbohydrates (NSC), allowed for an increased production of osmolytes and a higher potential fueling ion transport under subsequent salt condition, along with increased transcript levels of the cation/H ATPase. Second, LN pretreatment enhanced the transcript levels of stress signaling components and phytohormones pathway as well as antioxidant enzyme activities. The results indicate that early restrictions of N supply could enhance posterior survival under saline stress in poplar plants, which is important for plantation programs and restoration activities in semi-arid areas.
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http://dx.doi.org/10.1016/j.ecoenv.2021.112801DOI Listing
December 2021

Early mechanical cardiopulmonary resuscitation can improve outcomes in patients with non-traumatic cardiac arrest in the emergency department.

J Int Med Res 2021 Jun;49(6):3000605211025368

Emergency Department, The Third People's Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, Chengdu, Sichuan, PR China.

Objective: To compare the outcomes of patients with non-traumatic cardiac arrest (CA) who received early versus late mechanical cardiopulmonary resuscitation (CPR) with the Lund University Cardiac Assist System (LUCAS) device in the emergency department (ED).

Methods: This was a retrospective observational study in the ED of a single medical center performed from May 2018 to December 2019; 68 patients with CA were eligible. We grouped the patients according to the time to initiating LUCAS use after CA into an early group (≤4 minutes) and late group (>4 minutes).

Results: The rate of return of spontaneous circulation (ROSC) was higher in the early group vs the late group (69.2% vs 52.4%, respectively). The 4-hour survival rate was significantly higher in the early group vs the late group (83.3% vs 45.5%, respectively), and CPR duration was significantly shorter in the early group (23.3 ± 12.5 vs 31.1 ± 14.8 minutes, respectively).

Conclusion: Early mechanical CPR can improve the success of achieving ROSC and the 4-hour survival rate in patients with non-traumatic CA in the ED, considering that more benefits were observed in patients who received early vs late LUCAS device therapy.
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http://dx.doi.org/10.1177/03000605211025368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8246509PMC
June 2021

Will Healthcare Workers Accept a COVID-19 Vaccine When It Becomes Available? A Cross-Sectional Study in China.

Front Public Health 2021;9:664905. Epub 2021 May 20.

Emergency Department, The Third People's Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, The Second Affiliated Hospital Chengdu Clinical College of Chongqing Medical University, Chengdu, China.

The Coronavirus disease 2019 (COVID-19) vaccine is currently available. This timely survey was conducted to provide insight into on the willingness of healthcare workers (HCWs)to receive the vaccine and determine the influencing factors. This was a cross-sectional online survey. An online questionnaire was provided to all participants and they were asked if they would accept a free vaccine. The questionnaire gathered general demographic information, and included the General Health Questionnaire (GHQ-12); Myers-Briggs Type Indicator questionnaire (MBTI); Depression, Anxiety, and Stress Scales (DASS-21); and the 12-item Short Form Health Survey (SF-12). The data were collected automatically and electronically. Univariate analysis was done between all the variables and our dependent variable. Multivariable logistic regression models were employed to examine and identify the associations between the acceptance of the COVID-19 vaccine with the associated variables. We collected 505 complete answers. The participants included 269 nurses (53.27%), 206 clinicians (40.79%), 15 administrative staff (2.97%), and 15 other staff (2.97%). Of these, 76.63% declared they would accept the vaccine. The major barriers were concerns about safety, effectiveness, and the rapid mutation in the virus. Moreover, four factors were significantly associated with the willingness to receive the vaccine: (a) "understanding of the vaccine" (odds ratio (OR):2.322; 95% confidence interval [CI]: 1.355 to 3.979); (b) "worried about experiencing COVID-19" (OR 1.987; 95% CI: 1.197-3.298); (c) "flu vaccination in 2020" (OR 4.730; 95% CI: 2.285 to 9.794); and (d) "living with elderly individuals" (OR 1.928; 95% CI: 1.074-3.462). During the vaccination period, there was still hesitation in receiving the vaccine. The results will provide a rationale for the design of future vaccination campaigns and education efforts concerning the vaccine.
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http://dx.doi.org/10.3389/fpubh.2021.664905DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8172770PMC
June 2021

Tanshinone IIA enhances susceptibility of non-small cell lung cancer cells to NK cell-mediated lysis by up-regulating ULBP1 and DR5.

J Leukoc Biol 2021 08 28;110(2):315-325. Epub 2021 Apr 28.

Center for Traditional Chinese Medicine and Immunology Research, School of Basic Medical Sciences, Shanghai University of Traditional Chinese Medicine, Shanghai, P. R. China.

Natural killer (NK) cells have a great potential in cancer immunotherapy. However, their therapeutic efficacy is clinically limited owing to cancer cell immune escape. Therefore, it is urgently necessary to develop novel method to improve the antitumor immunity of NK cells. In the present study, it was found that the natural product tanshinone IIA (TIIA) enhanced NK cell-mediated killing of non-small cell lung cancer (NSCLC) cells. TIIA in combination with adoptive transfer of NK cells synergistically suppressed the tumor growth of NSCLC cells in an immune-incompetent mouse model. Furthermore, TIIA significantly inhibited the tumor growth of Lewis lung cancer (LLC) in an immune-competent syngeneic mouse model, and such inhibitory effect was reversed by the depletion of NK cells. Moreover, TIIA increased expressions of ULBP1 and DR5 in NSCLC cells, and inhibition of DR5 and ULBP1 reduced the enhancement of NK cell-mediated lysis by TIIA. Besides, TIIA increased the levels of p-PERK, ATF4 and CHOP. Knockdown of ATF4 completely reversed the up-regulation of ULBP1 and DR5 by TIIA in all detected NSCLC cells, while knockdown of CHOP only partly reduced these enhanced expressions in small parts of NSCLC cells. These results demonstrated that TIIA could increase the susceptibility of NSCLC cells to NK cell-mediated lysis by up-regulating ULBP1 and DR5, suggesting that TIIA had a promising potential in cancer immunotherapy, especially in NK cell-based cancer immunotherapy.
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http://dx.doi.org/10.1002/JLB.5MA1120-776RRDOI Listing
August 2021

Suppression of delayed rectifier K channels by gentamicin induces membrane hyperexcitability through JNK and PKA signaling pathways in vestibular ganglion neurons.

Biomed Pharmacother 2021 Mar 1;135:111185. Epub 2021 Feb 1.

Department of Physiology and Neurobiology & Centre for Ion Channelopathy, Medical College of Soochow University, Suzhou 215123, PR China; Jiangsu Key Laboratory of Neuropsychiatric Diseases, Soochow University, Suzhou 215123, PR China. Electronic address:

Aminoglycoside antibiotics, such as gentamicin, are known to have vestibulotoxic effects, including ataxia and disequilibrium. To date, however, the underlying cellular and molecular mechanisms are still unclear. In this study, we determined the role of gentamicin in regulating the sustained delayed rectifier K current (I) and membrane excitability in vestibular ganglion (VG) neurons in mice. Our results showed that the application of gentamicin to VG neurons decreased the I in a concentration-dependent manner, while the transient outward A-type K current (I) remained unaffected. The decrease in I induced by gentamicin was independent of G-protein activity and led to a hyperpolarizing shift of the inactivation V. The analysis of phospho-c-Jun N-terminal kinase (p-JNK) revealed that gentamicin significantly stimulated JNK, while p-ERK and p-p38 remained unaffected. Blocking Kv1 channels with α-dendrotoxin or pretreating VG neurons with the JNK inhibitor II abrogated the gentamicin-induced decrease in I. Antagonism of JNK signaling attenuated the gentamicin-induced stimulation of PKA activity, whereas PKA inhibition prevented the I response induced by gentamicin. Moreover, gentamicin significantly increased the number of action potentials fired in both phasic and tonic firing type neurons; pretreating VG neurons with the JNK inhibitor II and the blockade of the I abolished this effect. Taken together, our results demonstrate that gentamicin decreases the I through a G-protein-independent but JNK and PKA-mediated signaling pathways. This gentamicin-induced I response mediates VG neuronal hyperexcitability and might contribute to its pharmacological vestibular effects.
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http://dx.doi.org/10.1016/j.biopha.2020.111185DOI Listing
March 2021

de Winter electrocardiographic pattern related to diagonal branch occlusion.

Coron Artery Dis 2021 Sep;32(6):593-594

Emergency Department, The Third People's Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, The Second Affiliated Hospital Chengdu Clinical College of Chongqing Medical University, Chengdu, Sichuan, People's Republic of China.

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http://dx.doi.org/10.1097/MCA.0000000000000950DOI Listing
September 2021

VN-NDP: A Neighbor Discovery Protocol Based on Virtual Nodes in Mobile WSNs.

Sensors (Basel) 2019 Oct 31;19(21). Epub 2019 Oct 31.

School of Computer Science, Sichuan University, Chengdu 610065, China.

As an indispensable part of Internet of Things (IoT), wireless sensor networks (WSNs) are more and more widely used with the rapid development of IoT. The neighbor discovery protocols are the premise of communication between nodes and networking in energy-limited self-organizing wireless networks, and play an important role in WSNs. Because the node energy is limited, neighbor discovery must operate in an energy-efficient manner, that is, under the condition of a given energy budget, the neighbor discovery performance should be as good as possible, such that the discovery latency would be as small as possible and the discovered neighbor percentage as large as possible. The indirect neighbor discovery mainly uses the information of the neighbors that have been found by a pairwise discovery method to more efficiently make a re-planning of the discovery wake-up schedules of the original pairwise neighbor discovery, thereby improving the discovery energy efficiency. The current indirect neighbor discovery methods are mainly divided into two categories: one involves removing the inefficient active slots in the original discovery wake-up schedules, and the other involves adding some efficient active slots. However, the two categories of methods have their own limitations. The former does not consider that this removal operation destroys the integrity of the original discovery wake-up schedules and hence the possibility of discovering new neighbors is reduced, which adversely affects the discovered neighbor percentage. For the latter category, there are still inefficient active slots that were not removed in the re-planned wake-up schedules. The motivation of this paper is to combine the advantages of these two types of indirect neighbor discovery methods, that is, to combine the addition of efficient active slots and the removal of inefficient active slots. To achieve this goal, this paper proposes, for the first time, the concept of virtual nodes in neighbor discovery to maximize the integrity of the original wake-up schedules and achieve the goals of adding efficient active slots and removing inefficient active slots. Specifically, a virtual node is a collaborative group that is formed by nodes within a small range. The nodes in a collaborative group share responsibility for the activating task of one member node, and the combination of these nodes' wake-up schedules forms the full wake-up schedule of a node that only uses a pairwise method. In addition, this paper proposes a set of efficient group management mechanisms, and the key steps affecting energy efficiency are analyzed theoretically to obtain the energy-optimal parameters. The extended simulation experiments in multiple scenarios show that, compared with other methods, our neighbor discovery protocol based on virtual nodes (VN-NDP) has a significant improvement in average discovery delay and discovered neighbor percentage performance at a given energy budget. Compared with the typical indirect neighbor discovery algorithm EQS, a neighbor discovery with extended quorum system, our proposed VN-NDP method reduces the average discovery delay by up to 10 . 03 % and increases the discovered neighbor percentage by up to 18 . 35 % .
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http://dx.doi.org/10.3390/s19214739DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6864605PMC
October 2019

Electrical stimulation of the superior sagittal sinus suppresses A-type K currents and increases P/Q- and T-type Ca currents in rat trigeminal ganglion neurons.

J Headache Pain 2019 Aug 2;20(1):87. Epub 2019 Aug 2.

Department of Physiology and Neurobiology & Centre for Ion Channelopathy, Medical College of Soochow University, 199 Ren-Ai Road, Suzhou, 215123, People's Republic of China.

Background: Migraine is a debilitating neurological disorder involving abnormal trigeminovascular activation and sensitization. However, the underlying cellular and molecular mechanisms remain unclear.

Methods: A rat model of conscious migraine was established through the electrical stimulation (ES) of the dural mater surrounding the superior sagittal sinus. Using patch clamp recording, immunofluorescent labelling, enzyme-linked immunosorbent assays and western blot analysis, we studied the effects of ES on sensory neuronal excitability and elucidated the underlying mechanisms mediated by voltage-gated ion channels.

Results: The calcitonin gene-related peptide (CGRP) level in the jugular vein blood and the number of CGRP-positive neurons in the trigeminal ganglia (TGs) were significantly increased in rats with ES-induced migraine. The application of ES increased actional potential firing in both small-sized IB-negative (IB) and IB TG neurons. No significant changes in voltage-gated Na currents were observed in the ES-treated groups. ES robustly suppressed the transient outward K current (I) in both types of TG neurons, while the delayed rectifier K current remained unchanged. Immunoblot analysis revealed that the protein expression of Kv4.3 was significantly decreased in the ES-treated groups, while Kv1.4 remained unaffected. Interestingly, ES increased the P/Q-type and T-type Ca currents in small-sized IB TG neurons, while there were no significant changes in the IB subpopulation of neurons.

Conclusion: These results suggest that ES decreases the I in small-sized TG neurons and increases P/Q- and T-type Ca currents in the IB subpopulation of TG neurons, which might contribute to neuronal hyperexcitability in a rat model of ES-induced migraine.
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http://dx.doi.org/10.1186/s10194-019-1037-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6734278PMC
August 2019

Cholecystokinin type B receptor-mediated inhibition of A-type K channels enhances sensory neuronal excitability through the phosphatidylinositol 3-kinase and c-Src-dependent JNK pathway.

Cell Commun Signal 2019 06 18;17(1):68. Epub 2019 Jun 18.

Department of Physiology and Neurobiology & Centre for Ion Channelopathy, Medical College of Soochow University, 199 Ren-Ai Road, Suzhou, 215123, People's Republic of China.

Background: Cholecystokinin (CCK) is implicated in the regulation of nociceptive sensitivity of primary afferent neurons. Nevertheless, the underlying cellular and molecular mechanisms remain unknown.

Methods: Using patch clamp recording, western blot analysis, immunofluorescent labelling, enzyme-linked immunosorbent assays, adenovirus-mediated shRNA knockdown and animal behaviour tests, we studied the effects of CCK-8 on the sensory neuronal excitability and peripheral pain sensitivity mediated by A-type K channels.

Results: CCK-8 reversibly and concentration-dependently decreased A-type K channel (I) in small-sized dorsal root ganglion (DRG) neurons through the activation of CCK type B receptor (CCK-BR), while the sustained delayed rectifier K current was unaffected. The intracellular subunit of CCK-BR coimmunoprecipitated with Gα. Blocking G-protein signaling with pertussis toxin or by the intracellular application of anti-G antibody reversed the inhibitory effects of CCK-8. Antagonism of phosphatidylinositol 3-kinase (PI3K) but not of its common downstream target Akts abolished the CCK-BR-mediated I response. CCK-8 application significantly activated JNK mitogen-activated protein kinase. Antagonism of either JNK or c-Src prevented the CCK-BR-mediated I decrease, whereas c-Src inhibition attenuated the CCK-8-induced p-JNK activation. Application of CCK-8 enhanced the action potential firing rate of DRG neurons and elicited mechanical and thermal pain hypersensitivity in mice. These effects were mediated by CCK-BR and were occluded by I blockade.

Conclusion: Our findings indicate that CCK-8 attenuated I through CCK-BR that is coupled to the G-dependent PI3K and c-Src-mediated JNK pathways, thereby enhancing the sensory neuronal excitability in DRG neurons and peripheral pain sensitivity in mice.
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http://dx.doi.org/10.1186/s12964-019-0385-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582535PMC
June 2019

Melanocortin type 4 receptor-mediated inhibition of A-type K current enhances sensory neuronal excitability and mechanical pain sensitivity in rats.

J Biol Chem 2019 04 11;294(14):5496-5507. Epub 2019 Feb 11.

the Department of Physiology and Neurobiology and Centre for Ion Channelopathy, Medical College of Soochow University, Suzhou 215123, China,

α-Melanocyte-stimulating hormone (α-MSH) has been shown to be involved in nociception, but the underlying molecular mechanisms remain largely unknown. In this study, we report that α-MSH suppresses the transient outward A-type K current ( ) in trigeminal ganglion (TG) neurons and thereby modulates neuronal excitability and peripheral pain sensitivity in rats. Exposing small-diameter TG neurons to α-MSH concentration-dependently decreased This α-MSH-induced decrease was dependent on the melanocortin type 4 receptor (MC4R) and associated with a hyperpolarizing shift in the voltage dependence of A-type K channel inactivation. Chemical inhibition of phosphatidylinositol 3-kinase (PI3K) with wortmannin or of class I PI3Ks with the selective inhibitor CH5132799 prevented the MC4R-mediated response. Blocking G-protein signaling with pertussis toxin or by dialysis of TG neurons with the G-blocking synthetic peptide QEHA abolished the α-MSH-mediated decrease in Further, α-MSH increased the expression levels of phospho-p38 mitogen-activated protein kinase, and pharmacological or genetic inhibition of p38α abrogated the α-MSH-induced response. Additionally, α-MSH significantly increased the action potential firing rate of TG neurons and increased the sensitivity of rats to mechanical stimuli applied to the buccal pad area, and both effects were abrogated by blockade. Taken together, our findings suggest that α-MSH suppresses by activating MC4R, which is coupled sequentially to the G complex of the G-protein and downstream class I PI3K-dependent p38α signaling, thereby increasing TG neuronal excitability and mechanical pain sensitivity in rats.
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http://dx.doi.org/10.1074/jbc.RA118.006894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6462507PMC
April 2019

Aptamer-based fluorometric assay for direct identification of methicillin-resistant Staphylococcus aureus from clinical samples.

J Microbiol Methods 2018 10 20;153:92-98. Epub 2018 Sep 20.

Department of Medical Laboratory, Weifang Medical University, Weifang, Shandong 261053, PR China; Key Laboratory of Clinical Laboratory Diagnostics in the Universities of Shandong Province, Weifang Medical University, Weifang, Shandong 261053, PR China; Institute of Nanomedicine Technology, Weifang Medical University, Weifang, Shandong 261053, PR China. Electronic address:

Accurate and rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is of important clinical significance. In this study, a novel aptamer-based fluorometric assay was developed for detection of MRSA in clinical samples by coupling with immunomagnetic separation. The S. aureus cells in clinical specimens were enriched by magnetic separation. Following lysis by staphylococcal lysin, the PBP2a proteins were released from S. aureus cells and detected by the aptamer-based fluorometric assay. Without lengthy period of bacteria cultivation in the traditional susceptibility testing, this test has an overall testing time of only 2 h with the detection limit of 2.63 × 10 and 1.38 × 10 CFU/mL in PBS and spiked nasal swab, respectively. Since it is simple, rapid and sensitive, this method could be used for the detection of MRSA in various clinical samples.
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http://dx.doi.org/10.1016/j.mimet.2018.09.011DOI Listing
October 2018

Melatonin-mediated inhibition of Cav3.2 T-type Ca channels induces sensory neuronal hypoexcitability through the novel protein kinase C-eta isoform.

J Pineal Res 2018 May 8;64(4):e12476. Epub 2018 Mar 8.

Department of Physiology and Neurobiology & Centre for Ion Channelopathy, Medical College of Soochow University, Suzhou, China.

Recent studies implicate melatonin in the antinociceptive activity of sensory neurons. However, the underlying mechanisms are still largely unknown. Here, we identify a critical role of melatonin in functionally regulating Cav3.2 T-type Ca channels (T-type channel) in trigeminal ganglion (TG) neurons. Melatonin inhibited T-type channels in small TG neurons via the melatonin receptor 2 (MT receptor) and a pertussis toxin-sensitive G-protein pathway. Immunoprecipitation analyses revealed that the intracellular subunit of the MT receptor coprecipitated with Gα . Both shRNA-mediated knockdown of Gα and intracellular application of QEHA peptide abolished the inhibitory effects of melatonin. Protein kinase C (PKC) antagonists abolished the melatonin-induced T-type channel response, whereas inhibition of conventional PKC isoforms elicited no effect. Furthermore, application of melatonin increased membrane abundance of PKC-eta (PKC ) while antagonism of PKC or shRNA targeting PKC prevented the melatonin-mediated effects. In a heterologous expression system, activation of MT receptor strongly inhibited Cav3.2 T-type channel currents but had no effect on Cav3.1 and Cav3.3 current amplitudes. The selective Cav3.2 response was PKC dependent and was accompanied by a negative shift in the steady-state inactivation curve. Furthermore, melatonin decreased the action potential firing rate of small TG neurons and attenuated the mechanical hypersensitivity in a mouse model of complete Freund's adjuvant-induced inflammatory pain. These actions were inhibited by T-type channel blockade. Together, our results demonstrated that melatonin inhibits Cav3.2 T-type channel activity through the MT receptor coupled to novel G -mediated PKC signaling, subsequently decreasing the membrane excitability of TG neurons and pain hypersensitivity in mice.
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http://dx.doi.org/10.1111/jpi.12476DOI Listing
May 2018

Construction of an ultrahigh-density genetic linkage map for L. and identification of QTL for fruit yield.

Biotechnol Biofuels 2018 9;11. Epub 2018 Jan 9.

The Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agriculture Sciences, Haikou, China.

Background: As an important biofuel plant, the demand for higher yield L. is rapidly increasing. However, genetic analysis of and molecular breeding for higher yield have been hampered by the limited number of molecular markers available.

Results: An ultrahigh-density linkage map for a mapping population of 153 individuals was constructed and covered 1380.58 cM of the genome, with average marker density of 0.403 cM. The genetic linkage map consisted of 3422 SNP and indel markers, which clustered into 11 linkage groups. With this map, 13 repeatable QTLs (reQTLs) for fruit yield traits were identified. Ten reQTLs, -, -, -, -, -, -, -, -, - and - that control the number of fruits (NF) mapped to LGs 1, 2, 3, 4, 6, 7 and 8, whereas three reQTLs, -, - and - that control the total weight of fruits (TWF) mapped to LGs 1, 2 and 3, respectively. It is interesting that there are two candidate critical genes, which may regulate fruit yield. We also identified three pleiotropic reQTL pairs associated with both the NF and TWF traits.

Conclusion: This study is the first to report an ultrahigh-density genetic linkage map construction, and the markers used in this study showed great potential for QTL mapping. Thirteen fruit-yield reQTLs and two important candidate genes were identified based on this linkage map. This genetic linkage map will be a useful tool for the localization of other economically important QTLs and candidate genes for .
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http://dx.doi.org/10.1186/s13068-017-1004-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5759280PMC
January 2018

Phosphatidylcholine absence affects the secretion of lipodepsipeptide phytoxins in Pseudomonas syringae pv. syringae van Hall CFCC 1336.

Microbiol Res 2018 Jan 16;206:113-120. Epub 2017 Oct 16.

The Faculty of Life Science, Hubei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei University, China. Electronic address:

Pseudomonas syringae pv. syringae van Hall CFCC 1336 (Pss 1336) is the causal agent of bacterial disease of stone fruit trees, and also able to elicit hypersensitive response (HR) in non-host tobacco. It is known that this pathogen uses PCS-pathway to synthesize phosphatidylcholine (PC), and mutation of the pcs gene abolishes bacterial PC synthesis. Previous study also found that the 1336 pcs mutant lacking PC in its membrane phospholipids was unable to secrete HrpZ harpin and elicit HR in non-host plants. In this study, we further analyzed virulence of lipodepsipeptide phytoxins of Pss 1336 wild type (pcs), the 1336RM (pcs-/+) and the 1336 pcs- mutant, and found that the 1336 pcs- mutant was unable to cause necrosis of Chinese date fruits and inhibit fungal growth. HPLC analysis also showed that the 1336 pcs- mutant markedly reduced its secretion of lipodepsipeptide phytoxins. Analysis of semi-quantitative RT-PCR revealed that PC presence or absence did not affect gene expressions of SyrD, PseABC and PseEF efflux systems at transcriptional level. However, western blotting assays found that PseE and PseF present only in the cytoplasmic fractions but undetectable in the membrane extract of the 1336 pcs- mutant. PC absence obviously interrupted the translocation of two membrane-associated proteins PseE and PseF from cytoplasm to cell membranes to form an intact PseEF efflux system in bacterial membranes. Failure to form PseEF efflux system could be a major factor for less lipopeptide-phytoxin secretion. Our results demonstrate that PC in bacterial membrane phospholipids plays an important role in maintaining physiological functions of PseEF efflux system.
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http://dx.doi.org/10.1016/j.micres.2017.10.001DOI Listing
January 2018

Homeobox B4 inhibits breast cancer cell migration by directly binding to StAR-related lipid transfer domain protein 13.

Oncol Lett 2017 Oct 25;14(4):4625-4632. Epub 2017 Aug 25.

Department of Breast and Thyroid Surgery, The Affiliated Hospital of Jining Medical University, Jining 272129, P.R. China.

The present study aimed to investigate the role of homeobox B4 (HOXB4) in breast cancer. Analysis of The Cancer Genome Atlas data revealed that HOXB4 expression was positively associated with expression of the StAR-related lipid transfer domain protein 13 (STARD13), and the overall survival of patients with breast cancer. Immunohistochemistry and quantitative polymerase chain reaction assays demonstrated that HOXB4 expression was downregulated in breast cancer tissues compared with adjacent normal tissues and was additionally positively associated with STARD13 expression. HOXB4 promoted STARD13 expression in breast cancer cells. Chromatin immunoprecipitation and luciferase reporter assays confirmed that HOXB4 directly bound to the STARD13 promoter. Additionally, HOXB4 inhibited breast cancer cell migration and the epithelial-mesenchymal transition through the STARD13/Ras homolog (Rho) family member A/Rho associated protein kinase signaling pathway. HOXB4 overexpression enhanced the sensitivity of breast cancer cells to doxorubicin and reversed resistance in doxorubicin-resistant cells. Overall, the results indicated that HOXB4 inhibited breast cancer cell migration and enhanced the sensitivity of breast cancer cells to doxorubicin by targeting STARD13.
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http://dx.doi.org/10.3892/ol.2017.6825DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5649528PMC
October 2017

The comparative mitogenomics and phylogenetics of the two grouse-grasshoppers (Insecta, Orthoptera, Tetrigoidea).

Biol Res 2017 Oct 5;50(1):34. Epub 2017 Oct 5.

College of Oceanology and Food Science, Quanzhou Normal University, Quanzhou, 362000, Fujian, China.

Objective: This study aimed to reveal the mitochondrial genomes (mtgenomes) of Tetrix japonica and Alulatettix yunnanensis, and the phylogenetics of Orthoptera species.

Methods: The mtgenomes of A. yunnanensis and T. japonica were firstly sequenced and assembled through partial sequences amplification, and then the genome organization and gene arrangement were analyzed. Based on nucleotide/amino acid sequences of 13 protein-coding genes and whole mtgenomes, phylogenetic trees were established on 37 Orthoptera species and 5 outgroups, respectively.

Results: Except for a regulation region (A+T rich region), a total of 37 genes were found in mtgenomes of T. japonica and A. yunnanensis, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Orthoptera species. Phylogenetic tree based on 13 concatenated protein-coding nucleotide sequences were considered to be more suitable for phylogenetic reconstruction of Orthoptera species than amino acid sequences and mtgenomes. The phylogenetic relationships of Caelifera species were Acridoidea and Pamphagoidea > Pyrgomorphoidea > Pneumoroidea > Eumastacoidea > Tetrigoidea > Tridactyloidea. Besides, a sister-group relationship between Tettigonioidea and Rhaphidophoroidea was revealed in Ensifera.

Conclusion: Concatenated protein-coding nucleotide sequences of 13 genes were suitable for reconstruction of phylogenetic relationship in orthopteroid species. Tridactyloidea was a sister group of Tetrigoidea in Caelifera, and Rhaphidophoroidea was a sister group of Tettigonioidea in Ensifera.
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http://dx.doi.org/10.1186/s40659-017-0132-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5629798PMC
October 2017

Increased high-sensitivity C-reactive protein, erythrocyte sedimentation rate and lactic acid in stroke patients with internal carotid artery occlusion.

Arch Med Sci 2016 Jun 14;12(3):546-51. Epub 2015 Jan 14.

Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, China.

Introduction: Internal carotid artery occlusion (ICAO) causes high annual rates of mortality and morbidity. It has been established that atherosclerosis is the normal cause of ICAO. As the pathogenesis of atherosclerosis may involve blood lipids, inflammatory factors and other biomarkers, the aim of this study was to assess the changes in these biomarkers and investigate the relationship between these biomarkers and the development of ICAO in stroke patients.

Material And Methods: A total of 89 ischaemic stroke inpatients with ICAO (ICAO group) and 89 without ICAO (control group) were studied, retrospectively. The serum was collected from each patient on the 3(rd) day of admission, to measure the lipid parameters and biomarkers, e.g. high-sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and lactic acid (LA). Histories were taken including age, gender, smoking history, and disease history. Additional analysis was carried out to compare between the genders and evaluate the association between certain biomarkers and ICAO.

Results: Among the 89 ICAO cases in this study, the serum levels of hs-CRP, ESR and LA were significantly higher than those in the control group (p ≤ 0.001). No significant differences were found in the mean levels of total cholesterol, triacylglycerol, HDL cholesterol or glucose, or the known risk factors. Gender also had no influence on these biomarkers. Logistic regression analysis indicated that hs-CRP, ESR and LA were significantly associated with ICAO (p ≤ 0.05).

Conclusions: These results suggest that hs-CRP, ESR and LA are associated with ICAO in ischaemic stroke patients, but gender has no effect. Therefore, Hs-CRP, ESR and LA may be useful in the early detection of patients with ICAO.
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http://dx.doi.org/10.5114/aoms.2014.47879DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4889675PMC
June 2016

Absence of phosphatidylcholine in bacterial membranes facilitates translocation of Sec-dependent β-lactamase AmpC from cytoplasm to periplasm in two Pseudomonas strains.

Microb Pathog 2017 May 7;106:94-102. Epub 2016 Apr 7.

The Faculty of Life Science, Huibei Collaborative Innovation Center for Green Transformation of Bioresources, Hubei University, China. Electronic address:

Phosphatidylcholine (PC) is a rare membrane lipid in bacteria but crucial for virulence of various plant and animal pathogens. The pcs- mutant lacking PC in bacterial membranes of Pseudomonas syringae pv. syringae van Hall 1336 displayed more ampicillin resistance. Ampicillin susceptibility tests gave an IC50 (half maximal inhibitory concentration) of 52 mg/ml for Pseudomonas syringae pv. syringae van Hall 1336, 53 mg/ml for the complemented strain 1336 RM (pcs-/+) and 90 mg/ml for the 1336 pcs- mutant. Activity assay of β-lactamase in periplasmic extracts gave 0.050 U/mg for the 1336 wild type, 0.052 U/mg for the 1336RM (pcs-/+), 0.086 U/mg for the 1336 pcs- mutant. Analysis by western blotting showed that the content of AmpC enzyme was markedly different in periplasmic extracts between the wild-type and pcs- mutant strains. Reverse transcriptase PCR also showed that the presence or absence of PC in bacterial membranes did not affect the transcription of ampC gene. The phenotype of the pcs- mutant was able to be recovered to the wild type by introducing a wild-type pcs gene into the pcs- mutant. Similar results were also obtained from the soil-dwelling bacterium Pseudomonas sp. 593. Our results demonstrate that the absence of PC in bacterial membranes facilitates the translocation of Sec-dependent β-lactamase AmpC from cytoplasm to periplasm, and the enhanced ampicillin-resistance in the pcs- strains mainly comes from effective translocation of AmpC via Sec-pathway.
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http://dx.doi.org/10.1016/j.micpath.2016.04.010DOI Listing
May 2017

Out of the Sichuan Basin: Rapid species diversification of the freshwater crabs in Sinopotamon (Decapoda: Brachyura: Potamidae) endemic to China.

Mol Phylogenet Evol 2016 07 4;100:80-94. Epub 2016 Apr 4.

Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China. Electronic address:

Sinopotamon Bott, 1967 is the most speciose and widely distributed freshwater crab genus in East Asia. Our extensive sampling includes about 76% of the known Sinopotamon taxa, and nearly covers its entire distribution area. Based on mitochondrial cytochrome oxidase I (COI) and 16S rRNA, as well as nuclear 28S rRNA and histone H3, we reconstructed the Sinopotamon phylogeny using maximum likelihood and Bayesian approaches. The divergence time was estimated and multiple methods were used to conduct diversification analyses. The ancestral geographic distribution and character state were reconstructed. Three main clades (Clades I, II and III) that roughly correspond to their main geographic distribution ranges were recovered. Our results challenge the current view of the four major species groups based on the morphological differences in the male first gonopod (G1). The most recent common ancestor of Sinopotamon most likely originated from the Sichuan Basin and surrounding mountains (SBSM) and subsequently dispersed throughout central and eastern China. The exceptionally rapid, recent diversification was detected in Clade II. The high incidence of species-level non-monophyly found in Clade II can be explained by recent rapid radiation. Climatic changes, morphological innovations, range expansion and geographical heterogeneity may all contribute to the diversification in Sinopotamon. This study contributes to our knowledge on diversification of freshwater benthic macro-invertebrates in the East Asian inland ecosystem.
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http://dx.doi.org/10.1016/j.ympev.2016.04.003DOI Listing
July 2016

Different responses of soil microbial metabolic activity to silver and iron oxide nanoparticles.

Chemosphere 2016 Mar 7;147:195-202. Epub 2016 Jan 7.

Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, Jiangsu Province, PR China. Electronic address:

The knowledge regarding the effects of metal or metal oxide nanoparticles on soil microbial metabolic activity and key ecological functions is limited, relative to the information about their species diversity. For this reason, the responses of soil microbial metabolic activity to silver (AgNPs) and iron oxide (FeONPs) nanoparticles, along concentration gradients of each, were evaluated by microcalorimetry and soil nitrification potential. The changes in abundances of bacteria, eukaryotes and ammonia-oxidizing bacteria were measured by real time quantitative PCR. It was found that AgNP (at 0.1, 1 and 10 mg kg(-1) soil) amendments decreased soil microbial metabolic activity, nitrification potential and the abundances of bacteria and ammonia-oxidizing bacteria; on the contrary, FeONPs had the positive effects on soil microbial metabolic activity (at 1 and 10 mg kg(-1) soil) and soil nitrification potential (at 0.1 and 1 mg kg(-1) soil). Specific microbial metabolic activity and specific nitrification potential further revealed that metal or metal oxide nanoparticles could change the C and N cycles of the agricultural soil through influencing soil microbial metabolism. These findings could deepen the understanding of the influence of NPs on soil microorganisms and their driven soil ecology process.
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http://dx.doi.org/10.1016/j.chemosphere.2015.12.055DOI Listing
March 2016

A method for the further assembly of targeted unigenes in a transcriptome after assembly by Trinity.

Front Plant Sci 2015 14;6:843. Epub 2015 Oct 14.

University of Chinese Academy of Sciences Beijing, China.

RNA-sequencing has been widely used to obtain high throughput transcriptome sequences in various species, but the assembly of a full set of complete transcripts is still a significant challenge. Judging by the number of expected transcripts and assembled unigenes in a transcriptome library, we believe that some unigenes could be reassembled. In this study, using the nitrate transporter (NRT) gene family and phosphate transporter (PHT) gene family in Salicornia europaea as examples, we introduced an approach to further assemble unigenes found in transcriptome libraries which had been previously generated by Trinity. To find the unigenes of a particular transcript that contained gaps, we respectively selected 16 NRT candidate unigene pairs and 12 PHT candidate unigene pairs for which the two unigenes had the same annotations, the same expression patterns among various RNA-seq samples, and different positions of the proteins coded as mapped to a reference protein. To fill a gap between the two unigenes, PCR was performed using primers that mapped to the two unigenes and the PCR products were sequenced, which demonstrated that 5 unigene pairs of NRT and 3 unigene pairs of PHT could be reassembled when the gaps were filled using the corresponding PCR product sequences. This fast and simple method will reduce the redundancy of targeted unigenes and allow acquisition of complete coding sequences (CDS).
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http://dx.doi.org/10.3389/fpls.2015.00843DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4604318PMC
November 2015

Patterns of diversity, areas of endemism, and multiple glacial refuges for freshwater crabs of the genus Sinopotamon in China (Decapoda: Brachyura: Potamidae).

PLoS One 2013 4;8(1):e53143. Epub 2013 Jan 4.

Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.

Previous research has shown that the geographical distribution patterns of freshwater fishes and amphibians have been influenced by past climatic oscillations in China resulting from Pleistocene glacial activity. However, it remains unknown how these past changes have impacted the present-day distribution of Chinese freshwater crabs. This work describes the diversity and endemism of freshwater crabs belonging to Sinopotamon, a highly speciose genus endemic to China, and evaluates its distribution in terms of topography and past climatic fluctuations. Species diversity within Sinopotamon was found to be concentrated in an area from the northeastern edge of the Yunnan-Guizhou Plateau to the Jiangnan Hills, and three areas of endemism were identified. Multiple regression analysis between current climatic variables and Sinopotamon diversity suggested that regional annual precipitation, minimum temperature in the coldest month, and annual temperature range significantly influenced species diversity and may explain the diversity patterns of Sinopotamon. A comparison of ecological niche models (ENMs) between current conditions and the last glacial maximum (LGM) showed that suitable habitat for Sinopotamon in China severely contracted during the LGM. The coincidence of ENMs and the areas of endemism indicated that southeast of the Daba Mountains, and central and southeastern China, are potential Pleistocene refuges for Sinopotamon. The presence of multiple Pleistocene refuges within the range of this genus could further promote inter- and intraspecific differentiations, and may have led to high Sinopotamon species diversity, a high endemism rate and widespread distribution.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0053143PLOS
July 2013

Laparoscopic pneumovesical ureteral tapering and reimplantation for megaureter.

Authors:
Yunli Bi Yufang Sun

J Pediatr Surg 2012 Dec;47(12):2285-8

Department of Urology, Children's Hospital of Fudan University, Shanghai 201102, China.

Objective: To evaluate the efficacy of laparoscopic pneumovesical ureter reimplantation for congenital malformation involving the vesicoureteral junction in children.

Methods: From January 2005 to October 2010, 45 cases (comprising 61 ureters) were diagnosed as megaureter caused by vesicoureteral junction obstruction. A pneumovesical laparoscopic Cohen procedure was performed in all cases. Twelve of the ureters underwent excisional ureteral tapering. Ureteral diameters were obtained using ultrasonography and were divided into 4 groups according to the degree of dilatation.

Results: The procedure was completed in all but 2 patients, who were converted to open surgery. The mean operation time was 3.5h (range, 2-8h) for unilateral ureter cases, 3.7h (range, 3.5-4.5h) for duplicated ureter cases, and 5.4h (range, 3.5-9h) for bilateral cases. The mean duration of urethral catheter placement and hospital stay was 6.7 days (range, 3-14 days) and 8.3 days (range, 4-15 days), respectively. Thirty-five of the patients (48 ureters) were followed up by ultrasonography for 1-67 months (mean, 19.3 months). Ultrasound scans revealed improvement in the degree of dilatation of 32 ureters. In 1 patient, the ultrasound scan showed deterioration of ureteral dilatation. This patient developed stenosis at the neoureteral opening and underwent reoperation 6 months later. Fourteen patients were followed up by micturating cystourethrogram (MCU).Of these, 3 cases (4 ureters) exhibited reflux (2 unilateral cases of grade 1 reflux and grade 3 reflux, respectively, and 1 bilateral case of bilateral grade 1 reflux).

Conclusions: Pneumovesical ureteral reimplantation for vesicoureteral junction obstruction is feasible and effective. In this series, ultrasound scans showed improvement in most ureteral dilatation cases on follow-up.
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http://dx.doi.org/10.1016/j.jpedsurg.2012.09.020DOI Listing
December 2012

Enhanced muscle growth by plasmid-mediated delivery of myostatin propeptide.

J Biomed Biotechnol 2010 15;2010:862591. Epub 2010 Mar 15.

College of Animal Science and Technology, Shihezi University, Shihezi 832002, China.

Myostatin is a member of the transforming growth factor beta (TGF-beta) superfamily that functions as a negative regulator of skeletal muscle development and growth. Myostatin blockade therefore offers a strategy for promoting muscle growth in livestock production without resorting to genetic manipulation. In this report, we examined the effect of myostatin inhibition by plasmid-mediated delivery of a mutant myostatin propeptide (MProD76A), a natural inhibitor of myostatin, on the growth performance of mice. A significant increase in skeletal muscle mass was observed after a single intramuscular injection of naked plasmid DNA encoding MProD76A into mice. Enhanced muscle growth occurred because of myofiber hypertrophy, but no cardiac muscle hypertrophy and organomegaly was observed in the mice after myostatin inhibition by plasmid-mediated MProD76A delivery. These results demonstrate a promising approach to enhancing muscle growth that warrants further investigation in domestic animals.
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http://dx.doi.org/10.1155/2010/862591DOI Listing
June 2010

Comparison of synthesis of chelating resin silica-gel-supported diethylenetriamine and its removal properties for transition metal ions.

J Hazard Mater 2009 Apr 26;163(1):127-35. Epub 2008 Jun 26.

School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.

Four kinds of silica-gel (SG)-supported diethylenetriamine (DETA) chelating resins SG-DETA-1, SG-DETA-2, SG-DETA-3, and SG-DETA-4 were prepared by functionalization of silica-gel via so-called "heterogeneous-direct-amination" (hetero-DA), "homogeneous-direct-amination" (homo-DA), "heterogeneous end-group protection" (hetero-EGP), and "homogeneous end-group protection" (homo-EGP) routes, respectively. These functionalized reactions on silica-gel were confirmed through elemental analysis, infrared spectroscopy, X-ray diffractometry, porous analysis, and thermogravimetry. Element analysis revealed that the direct-amination routes and homogeneous condition were more beneficial than the corresponding end-group protection routes and heterogeneous condition to the syntheses of chelating resins with high N content. Several metal ions, such as Ag(+), Cu(2+), Ni(2+), Hg(2+), Zn(2+) and Pb(2+), were chosen as representatives to investigate the relationship between adsorption capacities and N content of ligands onto the surface of silica-gel. The experiments results showed that all resins, SG-DETA-1, SG-DETA-2, SG-DETA-3 and SG-DETA-4, had a better adsorption for Hg(2+) and Cu(2+) than others. One conclusion should be drawn from the above compared experiments, that is, higher N content of silica-gel resins does not ensure a higher utilization ratio of N.
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http://dx.doi.org/10.1016/j.jhazmat.2008.06.070DOI Listing
April 2009

Secretory expression of nattokinase from Bacillus subtilis YF38 in Escherichia coli.

Mol Biotechnol 2007 Nov 17;37(3):187-94. Epub 2007 Jul 17.

State Key Laboratory of Microbial Resources, Chinese Academy of Sciences, Beijing, China.

Nattokinase producing bacterium, B. subtilis YF38, was isolated from douchi, using the fibrin plate method. The gene encoding this enzyme was cloned by polymerase chain reaction (PCR). Cytoplasmic expression of this enzyme in E. coli resulted in inactive inclusion bodies. But with the help of two different signal peptides, the native signal peptide of nattokinase and the signal peptide of PelB, active nattokinase was successfully expressed in E. coli with periplasmic secretion, and the nattokinase in culture medium displayed high fibrinolytic activity. The fibrinolytic activity of the expressed enzyme in the culture was determined to reach 260 urokinase units per micro-liter when the recombinant strain was induced by 0.7 mmol l(-1) isopropyl-beta-D- thiogalactopyranoside (IPTG) at 20 degrees C for 20 h, resulting 49.3 mg active enzyme per liter culture. The characteristic of this recombinant nattokinase is comparable to the native nattokinase from B. subtilis YF38. Secretory expression of nattokinase in E. coli would facilitate the development of this enzyme into a therapeutic product for the control and prevention of thrombosis diseases.
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http://dx.doi.org/10.1007/s12033-007-0060-yDOI Listing
November 2007
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