Publications by authors named "Changsheng Wang"

58 Publications

QTLs and candidate genes analyses for fruit size under domestication and differentiation in melon (Cucumis melo L.) based on high resolution maps.

BMC Plant Biol 2021 Mar 3;21(1):126. Epub 2021 Mar 3.

Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture and Rural Affairs, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, 100081, Beijing, China.

Background: Melon is a very important horticultural crop produced worldwide with high phenotypic diversity. Fruit size is among the most important domestication and differentiation traits in melon. The molecular mechanisms of fruit size in melon are largely unknown.

Results: Two high-density genetic maps were constructed by whole-genome resequencing with two F segregating populations (WAP and MAP) derived from two crosses (cultivated agrestis × wild agrestis and cultivated melo × cultivated agrestis). We obtained 1,871,671 and 1,976,589 high quality SNPs that show differences between parents in WAP and MAP. A total of 5138 and 5839 recombination events generated 954 bins in WAP and 1027 bins in MAP with the average size of 321.3 Kb and 301.4 Kb respectively. All bins were mapped onto 12 linkage groups in WAP and MAP. The total lengths of two linkage maps were 904.4 cM (WAP) and 874.5 cM (MAP), covering 86.6% and 87.4% of the melon genome. Two loci for fruit size were identified on chromosome 11 in WAP and chromosome 5 in MAP, respectively. An auxin response factor and a YABBY transcription factor were inferred to be the candidate genes for both loci.

Conclusion: The high-resolution genetic maps and QTLs analyses for fruit size described here will provide a better understanding the genetic basis of domestication and differentiation, and provide a valuable tool for map-based cloning and molecular marker assisted breeding.
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http://dx.doi.org/10.1186/s12870-021-02904-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7931605PMC
March 2021

Gate-tunable high magnetoresistance in monolayer FeGeTe spin valves.

Phys Chem Chem Phys 2020 Nov;22(44):25730-25739

State Key Laboratory for Mesoscopic Physics and School of Physics, Peking University, Beijing 100871, P. R. China.

Ferromagnetic order in two-dimensional (2D) van der Waals crystals has been attracting much attention recently. Remarkably, room temperature metallic ferromagnetism is realized in 2D Fe3GeTe2. Here we design a monolayer (ML) Fe3GeTe2 spin-valve device by attaching two ends to ferromagnetic electrodes and applying a magnetic field to these ferromagnetic electrodes. We investigate the spin-involved transport characteristics of such a spin valve by using ab initio quantum transport simulation. A high magnetoresistance of ∼390% is obtained and significantly increased to 450-510% after the gates are introduced. The magnetoresistance of the ML Fe3GeTe2 spin valve is insensitive to the strain modulation. Our study provides a potential option for magnetic storage applications and will motivate further studies in spintronics based on this class of materials.
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http://dx.doi.org/10.1039/d0cp03761cDOI Listing
November 2020

Resonance-Enhanced Charge Delocalization in Carbazole-Oligoyne-Oxadiazole Conjugates.

J Am Chem Soc 2020 11 21;142(44):18769-18781. Epub 2020 Oct 21.

Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, Erlangen 91058, Germany.

There are notably few literature reports of electron donor-acceptor oligoynes, even though they offer unique opportunities for studying charge transport through "all-carbon" molecular bridges. In this context, the current study focuses on a series of carbazole-(C≡C)-2,5-diphenyl-1,3,4-oxadiazoles ( = 1-4) as conjugated π-systems in general and explores their photophysical properties in particular. Contrary to the behavior of typical electron donor-acceptor systems, for these oligoynes, the rates of charge recombination after photoexcitation increase with increasing electron donor-acceptor distance. To elucidate this unusual performance, we conducted detailed photophysical and time-dependent density functional theory investigations. Significant delocalization of the molecular orbitals along the bridge indicates that the bridging states come into resonance with either the electron donor or acceptor, thereby accelerating the charge transfer. Moreover, the calculated bond lengths reveal a reduction in bond-length alternation upon photoexcitation, indicating significant cumulenic character of the bridge in the excited state. In short, strong vibronic coupling between the electron-donating -arylcarbazoles and the electron-accepting 1,3,4-oxadiazoles accelerates the charge recombination as the oligoyne becomes longer.
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http://dx.doi.org/10.1021/jacs.0c04003DOI Listing
November 2020

Magnetic phase diagram of CrPS and its exchange interaction in contact with NiFe.

J Phys Condens Matter 2020 Jun 18;32(40):405804. Epub 2020 Jun 18.

State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, People's Republic of China.

The magnetic phase diagram of the two-dimensional van der Waals magnet CrPS and the exchange bias effect of CrPS in contact with NiFe film have been investigated. Based on the magnetic measurements, we figure out the relatively low spin-flop field and spin-flip field for CrPS, both of the spin transition phenomena are strongly affected by the temperature. The perpendicular exchange bias effect is studied in CrPS single-crystal flake covered with 5 nm NiFe. Meanwhile, the variation of the cooling field has a great influence on the exchange bias field and coercivity, which is mainly attributed to the competition between the Zeeman energy and the exchange coupling at the interface as well as the formation of the multi-domain state.
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http://dx.doi.org/10.1088/1361-648X/ab9e2dDOI Listing
June 2020

Synthesis of two new naphthalene-containing compounds and their bindings to human serum albumin.

J Biomol Struct Dyn 2020 Jun 12:1-14. Epub 2020 Jun 12.

School of Chemistry and Materials Science, Heilongjiang University, Harbin, China.

Two naphthalene-containing compounds, 4-hydroxy-6,7-dimethoxy-1-(4-(trifluoromethyl)phenyl)-2-naphthoic acid (A) and 4-hydroxy-6,7-dimethoxy-1-phenyl-2-naphthoic acid (B), were prepared by several steps. Their bindings to human serum albumin (HSA) were studied by ultraviolet-visible (UV-vis) absorption, fluorescence, synchronous fluorescence, three-dimensional fluorescence, circular dichroism (CD) spectroscopies and molecular docking. The crystal data of these compounds show the structure of the compounds. The results show that the mechanism of the interaction between compound A and HSA is mixed-quenching (both dynamic and static quenching), while that of compound B and HSA is static quenching. The number of binding sites, binding constants and binding distance () were obtained. The interaction processes are spontaneous. A mainly interacts with HSA through typical hydrophobic interaction, and B binds to HSA mainly by the hydrogen bonds and van der Waals forces. The conformation of HSA changes slightly after the addition of the compounds. Besides, molecular docking method was used to study the interaction details between the compounds and HSA. This is helpful to understand the absorption and metabolism of these two compounds in the body, and provides a basis for designing naphthalene-containing drugs. Communicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2020.1764867DOI Listing
June 2020

LncRNA HOXB-AS1 promotes cell growth in multiple myeloma via FUT4 mRNA stability by ELAVL1.

J Cell Biochem 2020 10 30;121(10):4043-4051. Epub 2019 Dec 30.

Department of Spinal Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.

Multiple myeloma (MM) is defined as the second most common hematological tumor in the globe. Long noncoding RNAs (lncRNAs) have been reported to play stimulative or suppressive role in the progression of different carcinomas. The investigation of lncRNAs in MM is still inadequate. LncRNA HOXB cluster antisense RNA 1 (HOXB-AS1) was once revealed to facilitate glioma progression by affecting cellular activities of glioma cells. However, whether HOXB-AS1 participates in the development of MM still remains an enigma. In this study, we unveiled that HOXB-AS1 was highly expressed in MM and loss-of-function assays certified that HOXB-AS1 obstruction suppressed MM cell proliferation, and stimulated cell apoptosis. In addition, HOXB-AS1 could modulate fucosyltransferase 4 (FUT4) and FUT4-mediated Wnt/β-catenin pathway. In subsequence, it was observed from mechanism assays that HOXB-AS1 enhanced the interaction between ELAVL1 and FUT4 so as to stabilize FUT4 messenger RNA. In the end, rescue experiments affirmed that HOXB-AS1 affected the cell growth through FUT4 in MM. In conclusion, the whole modulation mechanism of HOXB-AS1/ELAVL1/FUT4 axis in MM was validated in this study, which suggested that HOXB-AS1 might function as a powerful and promising therapeutic biomarker for the clinical treatment of patients with MM.
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http://dx.doi.org/10.1002/jcb.29573DOI Listing
October 2020

Room-Temperature-Formed PEDOT:PSS Hydrogels Enable Injectable, Soft, and Healable Organic Bioelectronics.

Adv Mater 2020 Jan 28;32(1):e1904752. Epub 2019 Oct 28.

Department of Bioengineering, University of California-Los Angeles, Los Angeles, CA, 90095, USA.

There is an increasing need to develop conducting hydrogels for bioelectronic applications. In particular, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hydrogels have become a research hotspot due to their excellent biocompatibility and stability. However, injectable PEDOT:PSS hydrogels have been rarely reported. Such syringe-injectable hydrogels are highly desirable for minimally invasive biomedical therapeutics. Here, an approach is demonstrated to develop injectable PEDOT:PSS hydrogels by taking advantage of the room-temperature gelation property of PEDOT:PSS. These PEDOT:PSS hydrogels form spontaneously after syringe injection of the PEDOT:PSS suspension into the desired location, without the need of any additional treatments. A facile strategy is also presented for large-scale production of injectable PEDOT:PSS hydrogel fibers at room temperature. Finally, it is demonstrated that these room-temperature-formed PEDOT:PSS hydrogels (RT-PEDOT:PSS hydrogel) and hydrogel fibers can be used for the development of soft and self-healable hydrogel bioelectronic devices.
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http://dx.doi.org/10.1002/adma.201904752DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6946856PMC
January 2020

Remarkable Boron Delivery Of iRGD-Modified Polymeric Nanoparticles For Boron Neutron Capture Therapy.

Int J Nanomedicine 2019 8;14:8161-8177. Epub 2019 Oct 8.

Department of Radiation Oncology, Ministry of Education Key Laboratory of Cancer Prevention and Intervention, The Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310009, People's Republic of China.

Purpose: Boron neutron capture therapy (BNCT) is an emerging binary radiotherapy, which is limited for application due to the challenge of targeted delivery into tumor nowadays. Here, we propose the use of iRGD-modified polymeric nanoparticles for active targeted delivery of boron and doxorubicin (DOX) in BNCT.

Methods: B-enriched BSH was covalently grafted to PEG-PCCL to prepare B-polymer, then surface-modified with iRGD. And, DOX was physically incorporated into polymers afterwards. Characterization of prepared polymers and in vitro release profile of DOX from polymers were determined by several methods. Cellular uptake of DOX was observed by confocal microscope. Accumulation of boron in cells and tissues was analyzed by ICP-MS. Biodistribution of DOX was studied by ex vivo fluorescence imaging and quantitative measurement. Tumor vascular normalization of Endostar for promoting delivery efficiency of boron on refractory B16F10 tumor was also studied.

Results: The polymers were monodisperse and spheroidal in water with an average diameter of 24.97 nm, which were relatively stable at physiological pH and showed a sustained release of DOX, especially at endolysosomal pH. Enhanced cellular delivery of DOX was found in iRGD-modified polymer group. Cellular boron uptake of iRGD-modified polymers in A549 cells was remarkably raised fivefold (209.83 ng B/10 cells) compared with BSH. The polymers represented prolonged blood circulation, enhanced tumor accumulation of B against BSH, and favorable tumor:normal tissue boron concentration ratios (tumor:blood = 14.11, tumor:muscle = 19.49) in A549 tumor-bearing mice 24 hrs after injection. Both fluorescence imaging and quantitative measurement showed the highest tumor accumulation of DOX at 24 hrs after injecting of iRGD-modified polymers. Improvement of vascular integrity and reduction of vascular mimicries were found after Endostar injection, and raised tumor accumulation of boron as well.

Conclusion: The developed nanoparticle is an inspiring candidate for the safe clinical application for BNCT.
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http://dx.doi.org/10.2147/IJN.S214224DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6790217PMC
December 2019

Structural characterization and osteoprotective effects of a polysaccharide purified from Achyranthes bidentata.

Int J Biol Macromol 2019 Oct 2;139:1063-1073. Epub 2019 Aug 2.

School of Clinical Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China. Electronic address:

Achyranthes bidentata has been traditionally used in China as a nature remedy for osteoporosis; however, little is known about the osteoprotective effects of its polysaccharides. The crude A. bidentata polysaccharide (AB70) was prepared by hot water extraction- ethanol precipitation method and a homogeneous fructan (ABW70-1) was purified from AB70 by ion-exchange and gel filtration column chromatography. Structural analysis indicated that ABW70-1 was composed of (2 → 1)-linked-β-d-fructofuranosyl (Fruf), (2 → 6)-linked-β-d-Fruf and (2 → 1,6)-linked-β-d-Fruf residues, and terminated with fructose and glucose residue. AB70 treatment for 13 weeks has shown a therapeutic effect on ovariectomized rats by restoring bone mineral content and biomechanical properties of the femur. Moreover, such osteoprotective effects of AB70 on bone mass were accompanied by improving trabecular bone microarchitecture and decreasing serum levels of bone turnover biomarkers. Furthermore, ABW70-1 stimulated the osteogenic differentiation of MC3T3-E1 cells by promoting cell proliferation, ALP activity, mineral nodules formation and the gene expression of Osx, Ocn and Bsp. These results suggest that A. bidentata polysaccharides have a great potential in the prevention and treatment of osteoporosis.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.08.013DOI Listing
October 2019

Dissecting a heterotic gene through GradedPool-Seq mapping informs a rice-improvement strategy.

Nat Commun 2019 07 5;10(1):2982. Epub 2019 Jul 5.

National Center for Gene Research, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200233, China.

Hybrid rice breeding for exploiting hybrid vigor, heterosis, has greatly increased grain yield. However, the heterosis-related genes associated with rice grain production remain largely unknown, partly because comprehensive mapping of heterosis-related traits is still labor-intensive and time-consuming. Here, we present a quantitative trait locus (QTL) mapping method, GradedPool-Seq, for rapidly mapping QTLs by whole-genome sequencing of graded-pool samples from F progeny via bulked-segregant analysis. We implement this method and map-based cloning to dissect the heterotic QTL GW3p6 from the female line. We then generate the near isogenic line NIL-FH676::GW3p6 by introgressing the GW3p6 allele from the female line Guangzhan63-4S into the male inbred line Fuhui676. The NIL-FH676::GW3p6 exhibits grain yield highly increased compared to Fuhui676. This study demonstrates that it may be possible to achieve a high level of grain production in inbred rice lines without the need to construct hybrids.
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http://dx.doi.org/10.1038/s41467-019-11017-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6611799PMC
July 2019

Two-dimensional ferromagnetism and driven ferroelectricity in van der Waals CuCrPS.

Nanoscale 2019 Mar;11(12):5163-5170

State Key Laboratory for Mesoscopic Physics and School of Physics, Peking University, Beijing 100871, P. R. China.

Multiferroic materials have the potential to be applied in novel magnetoelectric devices, for example, high-density non-volatile storage devices. During the last decades, research on multiferroic materials was focused on three-dimensional (3D) materials. However, 3D materials suffer from dangling bonds and quantum tunneling in nano-scale thin films. Two-dimensional (2D) materials might provide an elegant solution to these problems, and thus are highly in demand. Using first-principles calculations, we predicted ferromagnetism and electric-field-driving ferroelectricity in the monolayer and even in the few-layers of CuCrP2S6. Although the total energy of the ferroelectric phase of the monolayer is higher than that of the antiferroelectric phase, the ferroelectric phases can be realized by applying a large electric field. Besides the degrees of freedom in the common multiferroic materials, the valley degree of freedom is also polarized, according to our calculations. The spins, electric dipoles and valleys are coupled with each other as shown in the computational results. In our experiment, we observed the out-of-plane ferroelectricity in few-layer CuCrP2S6 (approximately 13 nm thick) at room temperature. 2D ferromagnetism of few-layers is inferred from the magnetic hysteresis loops of the massively stacked nanosheets at 10 K. The experimental observations support our calculations very well. Our findings may provide a series of 2D materials for further device applications.
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http://dx.doi.org/10.1039/c9nr00738eDOI Listing
March 2019

A fructooligosaccharide from Achyranthes bidentata inhibits osteoporosis by stimulating bone formation.

Carbohydr Polym 2019 Apr 9;210:110-118. Epub 2019 Jan 9.

School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China. Electronic address:

Achyranthes bidentata is used as a medicinal herb prescribed for the treatment of osteoporosis in China. The anti-osteoporosis activity of the crude polysaccharide from A. bidentata, AB50, was evaluated by ovariectomized rats. The results indicated that AB50 has prominent osteoprotective effects, which was comparable to positive control. To further explore which ingredients are responsible for these effects, a novel fructan, ABW50-1 (1260 Da), was purified for the first time and characterized by chemical methods and nuclear magnetic resonance. The results revealed that ABW50-1 was composed of →2)-β-D-Fruf-(1→, →2)-β-D-Fruf-(1, 6→ and →2)-β-D-Fruf-(6→, terminated with Glu and Fru residues. Morphological analyses indicated that ABW50-1 was fragmented and contained a branched structure. Furthermore, ABW50-1 significantly increased the relative fluorescence intensity of bone mass, without side effects, in a zebrafish model of glucocorticoid-induced osteoporosis (GIOP). Thus, ABW50-1 shows potential for developing new anti-osteoporosis agents for osteoporosis therapy.
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http://dx.doi.org/10.1016/j.carbpol.2019.01.026DOI Listing
April 2019

Rapamycin reduces mortality in acute-stage paraquat-induced toxicity in zebrafish.

Singapore Med J 2019 May 7;60(5):241-246. Epub 2018 Nov 7.

Emergency Department, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.

Introduction: Paraquat (PQ) intoxication is frequently associated with a high mortality rate. No specific treatment has been shown to reduce mortality in victims within the first 72 hours. We investigated the protective effects of rapamycin (Rapa) against PQ-induced toxicity in a zebrafish model.

Methods: To determine the maximum nonlethal concentration (MNLC) and lethal concentration 50 (LC50) of Rapa, zebrafish were treated at 2-5 days post fertilisation (dpf) and their mortality was recorded every 24 hours. At 5 dpf, the zebrafish were treated with PQ 100 µg/mL or PQ+Rapa (MNLC, 1/3 MNLC or 1/9 MNLC) for 72 hours, and the rate of survival was recorded every 24 hours. Reverse transcription-polymerase chain reaction was used to test the signalling pathway of mTOR (mammalian target of rapamycin).

Results: MNLC and LC50 of Rapa were determined to be 6.7 µg/mL and 28.9 µg/mL, respectively. At 48 hours, the PQ+Rapa groups had much lower mortality than the PQ group. The rates of survival of the PQ+Rapa groups were 43.33% (MNLC), 53.89% (1/3 MNLC) and 44.45% (1/9 MLNC), as compared to 19.45% in the PQ group, with the 1/3 MNLC group showing the highest rate of survival (p < 0.001). atg1 was slightly activated in the PQ group. In the PQ+Rapa groups, the expression of atg1 was markedly increased, suggesting strengthening of the autophagy process.

Conclusion: Rapa can increase the rate of survival of PQ-intoxicated zebrafish by inhibiting mTOR complex 1 and activating autophagy. Rapa could be an alternative first-line drug in the treatment of PQ poisoning.
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http://dx.doi.org/10.11622/smedj.2018132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6535450PMC
May 2019

UPLC/Q-TOF-MS-based metabolomics study of the anti-osteoporosis effects of Achyranthes bidentata polysaccharides in ovariectomized rats.

Int J Biol Macromol 2018 Jun 1;112:433-441. Epub 2018 Feb 1.

School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, PR China. Electronic address:

Osteoporosis is a frequent disease among the elderly especially in postmenopausal women. Achyranthes bidentata is a traditional Chinese medicine used to strengthen bones. Here, A. bidentata polysaccharides (ABPs) were confirmed to have anti-osteoporosis effects. This study discovered biomarkers by comparing normal and osteoporosis rats and evaluated the effects of ABPs on osteoporosis based on the UPLC/Q-TOF-MS-based metabolomics analysis. We could then predict the underlying mechanisms from the perspective of metabolomics. Osteoporotic rats were treated with ABPs, and serum was then sampled for metabolic analysis. Glutarylcarnitine, lysoPC (18:1) and 9-cis-retinoic acid were identified as biomarkers. The ABPs could significantly increase these biomarkers, and this indicated that ABPs curing osteoporosis regulated lipid metabolism. The UPLC/Q-TOF-MS-based metabolomics analysis offered a potential strategy to evaluate the anti-osteoporosis effects of ABPs and to explain the relative mechanisms. Furthermore, the ABPs have good potential for treating osteoporosis.
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http://dx.doi.org/10.1016/j.ijbiomac.2018.01.204DOI Listing
June 2018

Anti-osteoporosis activity of a novel Achyranthes bidentata polysaccharide via stimulating bone formation.

Carbohydr Polym 2018 Mar 30;184:288-298. Epub 2017 Dec 30.

School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China. Electronic address:

Achyranthes bidentata is an important Traditional Chinese Medicine for the treatment of osteoporosis. In this study, A. bidentata polysaccharide (ABPB), which was extracted with alkali from the root of A. bidentata at room temperature, significantly increased the bone mineral density, bone mineral content, trabecular thickness, trabecular number and biomechanical properties of ovariectomized (OVX) rats, indicating that ABPB had prominent curative effects on osteoporosis in OVX rats. A novel polysaccharide (ABPB-3) was purified from ABPB, and its structure was characterized as a repeating unit consisting of →4)-α-d-GalpA-(1→, →2,4)-α-l-Rhap-(1→, →5)-α-l-Araf-(1→, →2,3,5)-α-l-Araf-(1→, →3)-β-d-Galp-(1→, →3,4,6)-β-d-Galp-(1→, terminated with α-l-Araf, α-l-Rhap and β-d-Galp. Up to now, there were no literature reports relevant to the structure of ABPB-3. In the zebrafish model of glucocorticoid-induced osteoporosis (GIOP), ABPB-3 significantly increased the relative fluorescence intensity of the skull bone mass in a concentration-dependent manner, indicating that it stimulated bone formation activity. Thus, ABPB and ABPB-3 have the potential to be used for the anti-osteoporosis medicine.
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http://dx.doi.org/10.1016/j.carbpol.2017.12.070DOI Listing
March 2018

Neural differentiation of bone marrow mesenchymal stem cells with human brain-derived neurotrophic factor gene-modified in functionalized self-assembling peptide hydrogel in vitro.

J Cell Biochem 2019 03 9;120(3):2828-2835. Epub 2018 Dec 9.

Department of Orthopedics, The First Affiliated Hospital of Fujian Medical University (FMU), Fuzhou, People's Republic of China.

Objective: To investigate the biocompatibility and differentiation of human brain-derived neurotrophic factor (hBDNF) gene-modified bone marrow mesenchymal stem cells (hBDNF-rMSCs) in a functionalized self-assembling peptide hydrogel.

Methods: hBDNF was engineered in rMSCs using adenovirus vector and the enhanced green fluorescence protein (eGFP) was used as a reporter gene. Mesenchymal stem cell-specific surface markers (CD90, CD29, and CD45) were used for identifying rat-derived MSCs. Fluorescence microscope was used to detect the transfection of rMSCs. hBDNF-rMSCs and control cells (eGFP-rMSCs) were seeded in a functional self-assembling peptide hydrogel (RADA16-PRG hydrogel) and a control hydrogel (RADA16 hydrogel). Cells were divided into three groups (hBDNF-rMSCs + RADA16 hydrogel, hBDNF-rMSCs + RADA16-PRG hydrogel, and eGFP-rMSCs + RADA16-PRG hydrogel) and a control group (eGFP-rMSCs + RADA16 hydrogel). Cell growth, cell proliferation, expression of hBDNF-mRNA, the level of hBDNF, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP) protein were analyzed for each group.

Results: rMSCs were positive for CD90 and CD29 and negative for CD45, green fluorescence was strongly visible at 72 hours after transfection. Compared with control group, the expression of hBDNF-mRNA and levels of hBDNF protein in both hBDNF group were significantly increased (P < 0.01), the cell growth, cell proliferation, and levels of NSE and GFAP protein were significantly increased in three groups ( P < 0.01). Cell growth, cell proliferation, expression of hBDNF-mRNA, and levels of hBDNF, NSE, and GFAP protein in hBDNF-rMSCs + RADA16-PRG hydrogel group were significantly higher than that of hBDNF-rMSCs + RADA16 hydrogel group ( P < 0.01).

Conclusion: Bone marrow MSCs can be induced into neural cells by the human brain-derived neurotrophic factor gene in a RADA16-PRG functionalized self-assembling peptide hydrogel.
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http://dx.doi.org/10.1002/jcb.26408DOI Listing
March 2019

Effect and placental transfer of dexmedetomidine during caesarean section under epidural anaesthesia.

J Int Med Res 2017 Jun 28;45(3):964-972. Epub 2017 Apr 28.

Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China.

Objective To investigate the neonatal effect and placental transfer of dexmedetomidine during caesarean section under epidural anaesthesia. Methods Forty parturients with a single newborn who were scheduled for caesarean section were enrolled. Patients received 0.5 µg/kg dexmedetomidine 10 min after epidural anaesthesia, followed by 0.5 µg/kg/h until abdominal closure (Dex group) or infusion of normal saline (NS group). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were monitored before infusion (T0), 10 min after infusion (T1), at delivery (T2), and at the end of the operation (T3). Umbilical vein and artery blood was collected. Apgar scores were evaluated at 1 and 5 min after delivery. Results SBP, DBP, and HR in the Dex group were decreased at T3 compared with T0 (116 ± 10.4 vs 111 ± 9.2 mmHg, 74 ± 6.7 vs 66 ± 7.9 mmHg, 91 ± 12.1 vs 71 ± 8.4 beats/min, respectively, P < 0.05). HR was lower at T1, T2, and T3 in the Dex group compared with the NS group ( P < 0.05). There were no significant differences in blood gases and Apgar scores between the groups ( P > 0.05). Conclusion Dexmedetomidine during caesarean section under epidural anaesthesia is beneficial to parturients. The placental transfer rate is 0.68.
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http://dx.doi.org/10.1177/0300060517698330DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5536431PMC
June 2017

Valley Pseudospin with a Widely Tunable Bandgap in Doped Honeycomb BN Monolayer.

Nano Lett 2017 03 22;17(3):2079-2087. Epub 2017 Feb 22.

Collaborative Innovation Center of Quantum Matter , Beijing 100871, China.

Valleytronics is a promising paradigm to explore the emergent degree of freedom for charge carriers on the energy band edges. Using ab initio calculations, we reveal that the honeycomb boron nitride (h-BN) monolayer shows a pair of inequivalent valleys in the vicinities of the vertices of hexagonal Brillouin zone even without the protection of the C symmetry. The inequivalent valleys give rise to a 2-fold degree of freedom named the valley pseudospin. The valley pseudospin with a tunable bandgap from deep ultraviolet to far-infrared spectra can be obtained by doping h-BN monolayer with carbon atoms. For a low-concentration carbon periodically doped h-BN monolayer, the subbands with constant valley Hall conductance are predicted due to the interaction between the artificial superlattice and valleys. In addition, the valley pseudospin can be manipulated by visible light for high-concentration carbon doped h-BN monolayer. In agreement with our calculations, the circularly polarized photoluminescence spectra of the BNC sample show a maximum valley-contrasting circular polarization of 40% and 70% at room temperature and 77 K, respectively. Our work demonstrates a class of valleytronic materials with a controllable bandgap.
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http://dx.doi.org/10.1021/acs.nanolett.7b00271DOI Listing
March 2017

An unexpected copper-catalyzed carbonylative acetylation of amines.

Chem Commun (Camb) 2016 12;53(1):142-144

Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Straße 29a, 18059 Rostock, Germany.

A novel copper-catalyzed carbonylative acetylation of amines has been developed. With peroxide as the oxidant as well as the methyl source with a copper catalyst under CO pressure, good yields of N-acetyl amides could be obtained. Notably, this is the first example of carbonylative acetylation.
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http://dx.doi.org/10.1039/c6cc08929aDOI Listing
December 2016

Copper-Catalyzed Alkoxycarbonylation of Alkanes with Alcohols.

ChemSusChem 2017 04 21;10(7):1341-1345. Epub 2016 Dec 21.

Leibniz-Institut für Katalyse e.V. an der, Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany.

Esters are important chemicals widely used in various areas, and alkoxycarbonylation represents one of the most powerful tools for their synthesis. In this communication, a new copper-catalyzed carbonylative procedure for the synthesis of aliphatic esters from cycloalkanes and alcohols was developed. Through direct activation of the Csp3 -H bond of alkanes and with alcohols as the nucleophiles, the desired esters were prepared in moderate-to-good yields. Paraformaldehyde could also be applied for in situ alcohol generation by radical trapping, and moderate yields of the corresponding esters could be produced. Notably, this is the first report on copper-catalyzed alkoxycarbonylation of alkanes.
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http://dx.doi.org/10.1002/cssc.201601587DOI Listing
April 2017

Synergetic crystallization in a NdFeB/α-Fe nanocomposite under electron beam exposure conditions.

Nanoscale 2016 Oct;8(42):18221-18227

School of Physics, Peking University, Beijing, 100871, P. R. China.

NdFeB/α-Fe nanocomposite magnets are prepared through electron beam exposure with a greatly reduced annealing time of 0.1 s. This is by far the most effective approach due to the effect of an extremely high heating rate featuring a rapid thermal process. The impact that the rapid thermal process has on crystallization is expounded by the introduction of the Landau model and Langevin dynamical simulations. The change of crystallization sequence from the α-Fe phase preceding the NdFeB phase under conventional annealing conditions, to synergetic crystallization under electron beam conditions is investigated. Synergetic crystallization results in more intense interaction between the α-Fe phase and the NdFeB phase in order to refine the microstructure as the fraction of Fe increases within our addition range. Improved uniformity, and shifts in the microstructure and distribution of the α-Fe phase contribute to the improvement of the magnetic properties. Compared with conventional furnace annealing ones, the magnetic properties of samples under electron beam exposure conditions are improved. For the NdFeBNbGa alloy, coercivity is enhanced from 4.56 kOe to 6.73 kOe, remanence ratio increases from 0.75 to 0.79, and a superior squareness of the hysteresis loop is achieved.
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http://dx.doi.org/10.1039/c6nr06884gDOI Listing
October 2016

Stability and its mechanism in Ag/CoO/Ag interface-type resistive switching device.

Sci Rep 2016 10 19;6:35630. Epub 2016 Oct 19.

State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, P.R. China.

Stability is an important issue for the application of resistive switching (RS) devices. In this work, the endurance and retention properties of Ag/CoO/Ag interface-type RS device were investigated. This device exhibits rectifying I-V curve, multilevel storage states and retention decay behavior, which are all related to the Schottky barrier at the interface. The device can switch for thousands of cycles without endurance failure and shows narrow resistance distributions with relatively low fluctuation. However, both the high and low resistance states spontaneously decay to an intermediate resistance state during the retention test. This retention decay phenomenon is due to the short lifetime τ (τ = 0.5 s) of the metastable pinning effect caused by the interface states. The data analysis indicated that the pinning effect is dependent on the depth and density of the interface state energy levels, which determine the retention stability and the switching ratio, respectively. This suggests that an appropriate interface structure can improve the stability of the interface-type RS device.
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http://dx.doi.org/10.1038/srep35630DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5069483PMC
October 2016

[Effectiveness of long segment fixation combined with vertebroplasty for severe osteoporotic thoracolumbar compressive fractures].

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2013 Nov;27(11):1331-7

Department of Spine and Orthopedics, the First Affiliated Hospital of Fujian Medical University, Fuzhou Fujian, 350005, P.R.China.

Objective: To study the effectiveness of long segment fixation combined with vertebroplasty (LSF-VP) for severe osteoporotic thoracolumbar compressive fractures with kyphosis deformity.

Methods: Between March 2006 and May 2012, a retrospective analysis was made on the clinical data of 48 cases of severe osteoporotic thoracolumbar compressive fractures with more than 50% collapse of the anterior vertebral body or more than 400 of sagittal angulation, which were treated by LSF-VP in 27 cases (LSF-VP group) or percutaneous kyphoplasty (PKP) in 21 cases (PKP group). All patients suffered from single thoracolumbar vertebral compressive fracture at T11 to L2. There was no significant difference in gender, age, spinal segment, and T values of bone mineral density between 2 groups (P > 0.05). The effectiveness of the treatment was appraised by visual analogue scale (VAS), Cobb angle of thoracolumbar kyphosis, height of anterior/posterior vertebral body, and compressive ratio of vertebrae before and after operations.

Results: The LSF-VP group had longer operation time, hospitalization days, and more bone cement injection volume than the PKP group, showing significant differences (P < 0.05). Intraoperative blood loss in LSF-VP group ranged from 220 to 1,050 mL (mean, 517 mL). No pulmonaryor cerebral embolism or cerebrospinal fluid leakage was found in both groups. Asymptomatic bone cement leakage was found in 3 cases of LSF-VP group and 2 cases of PKP group. The patients were followed up for 16-78 months (mean, 41.1 months) in LSF-VP group, and 12-71 months (mean, 42.1 months) in PKP group. No fixation failure such as loosened or broken pedicle screw was found in LSF-VP group during the follow-up, and no re-fracture or adjacent vertebral body fracture was found. Two cases in PKP group at 39 and 56 months after operation respectively were found to have poor maintenance of vertebral height and loss of rectification (Cobb angle was more than 40 degrees) with recurrence of pain, which were treated by second surgery of LSF-VP; another case had compressive fracture of the adjacent segment and thoracolumbar kyphosis at 16 months after operation, which was treated by second surgery of LSF-VP. There were significant differences in the other indexes between each pair of the three time points (P < 0.05), except the Cobb angle of thoracolumbar kyphosis, and the height of posterior vertebral body between discharge and last follow-up in LSF-VP group, and except the Cobb angle of thoracolumbar kyphosis and compressive ratio of bertebrae between discharge and last follow-up in PKP group (P > 0.05). After operation, the other indexes of LSF-VP group were significantly better than those of PKP group at each time point (P < 0.05), except the VAS score and the height of posterior vertebral body at discharge (P > 0.05).

Conclusion: The effectiveness of LSF-VP is satisfactory in treating severe osteoporotic thoracolumbar compressive fractures with kyphosis deformity. LSF-VP can acquire better rectification of kyphosis and recovery of vertebral body height than PKP.
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November 2013

[Osteogenic effect of peptides anchored aminated tissue engineered bone for repairing femoral defect in rats].

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2013 May;27(5):520-8

Department of Spinal Surgery, the First Affiliated Hospital of Fujian Medical University, Fuzhou Fujian, 350005, P.R.China.

Objective: To study the osteogenic effects of a new type of peptides anchored aminated-poly-D, L-lactide acid (PA/PDLLA) scaffold in repairing femoral defect in rats.

Methods: The PDLLA scaffolds were treated by ammonia plasma and subsequent anchor of Gly-Arg-Gly-Asp-Ser (GRGDS) peptides via amide linkage formation. Thus PA/PDLLA scaffolds were prepared. The bone marrow was harvested from the femur and tibia of 4 4-week-old Sprague Dawley (SD) rats, and bone marrow mesenchymal stem cells (BMSCs) were isolated and cultured by whole bone marrow adherence method. BMSCs-scaffold composites were prepared by seeding osteogenic-induced BMSCs at passages 3-6 on the PA/PDLLA and PDLLA scaffolds. The right femoral defects of 8 mm in length were prepared in 45 adult male SD rats (weighing, 350-500 g) and the rats were divided into 3 groups (n=15) randomly. BMSCs-PA/PDLLA (PA/PDLLA group) or BMSCs-PDLLA (PDLLA group) composites were used to repair defects respectively, while defects were not treated as blank control (blank control group). General state of the rats after operation was observed. At 4, 8, and 12 weeks after operation, general, radiological, histological, micro-CT observations and real-time fluorescent quantitative PCR were performed.

Results: Two rats died after operation, which was added; the other rats survived to the end of the experiment. At each time point after operation, general and radiological observations showed more quick and obvious restoration in PA/PDLLA group than in PDLLA group; no bone repair was observed in blank control group. The X-ray scores were the highest in PA/PDLLA group, higher in PDLLA group, and the lowest in blank control group; showing significant difference in multiple comparison at the other time (P < 0.05) except between blank control group and PDLLA group at 4 weeks (P > 0.05). The X-ray scores showed an increasing trend in PDLLA group and PA/PDLLA group with time (P < 0.05). Histological and micro-CT observations showed the best osteogenesis in PA/PDLLA group, better in PDLLA group, and worst in blank control group. Comparison between groups had significant differences (P < 0.05) in bone mineral density, bone volume/total volume of range of interest, trabecular number, and structure model index. Significant differences (P < 0.05) were found in the expression levels of osteogenesis-related genes, such as osteocalcin, alkaline phosphatase, collagen type I, bone morphogenetic protein 2, and osteopontin when compared PA/PDLLA group with the other groups by real-time fluorescent quantitative PCR analysis.

Conclusion: The PA/PDLLA scaffolds can accelerate the repair of femoral defects in rats.
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May 2013

Radiation-induced sarcoma in bronchial stump after thoracic radiation therapy for small-cell lung cancer.

J Cancer Res Ther 2011 Apr-Jun;7(2):198-200

Department of Pathology, Beijing Friendship Hospital, Capital Medical University, Beijing, Republic of China.

We report a rare case of radiation-induced sarcoma (RIS) that arose in the right bronchial stump, 8 years after right pneumonectomy followed by adjuvant chemotherapy and thoracic radiotherapy for a localized small-cell lung cancer. The patient was treated in 2002 with 6 MV X-ray irradiation in a total dose of 60 Gy. Eight years after the end of radiotherapy, he presented with an undifferentiated high-grade pleomorphic sarcoma. Although an increased rate of soft tissue sarcoma has been reported after radiotherapy for some solid cancers or lymphomas, to our knowledge, this is the first report of RIS related to small-cell lung cancer.
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http://dx.doi.org/10.4103/0973-1482.82924DOI Listing
November 2011

Enforced expression of METCAM/MUC18 increases tumorigenesis of human prostate cancer LNCaP cells in nude mice.

J Urol 2011 Apr 19;185(4):1504-12. Epub 2011 Feb 19.

Department of Microbiology and Immunology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia, USA.

Purpose: Metastasis cell adhesion molecule/MUC18, a cell adhesion molecule in the Ig-like gene super family, is a key determinant in prostate cancer cell progression. However, the mechanisms by which human metastasis cell adhesion molecule/MUC18 stimulates progression are poorly understood. To investigate this and determine whether human metastasis cell adhesion molecule/MUC18 may act as a possible tumor progression gene, we studied the effect of its enforced expression on LNCaP cell tumorigenesis.

Materials And Methods: We subcutaneously co-injected a metastasis cell adhesion molecule/MUC18 expressing LNCaP clone and control clones/cells with Matrigel™ into nude mice, observed tumor formation of these cells and measured tumors at different times. To understand the mechanisms we also determined the expression of several downstream key effectors of metastasis cell adhesion molecule/MUC18 in subcutaneous tumors and compared them to those in previously obtained orthotopic (prostatic) tumors.

Results: Tumors derived from human metastasis cell adhesion molecule/MUC18 expressing LNCaP clones/cells appeared about 18 days earlier than the empty vector transfected clone/cells. Enforced expression of human metastasis cell adhesion molecule/MUC18 also increased tumor take 2-fold, tumorigenicity 10 to 12-fold and final tumor weight 5-fold. Enforced expression appeared to render the cells with increased levels of the proliferation indexes Ki67 and proliferating cell nuclear antigen, the survival index phospho-AKT, and the angiogenesis indexes vascular endothelial growth factor, vascular endothelial growth factor receptor 2 and CD31. However, it did not significantly render the cells with altered levels of various apoptosis indexes.

Conclusions: Enforced expression of human metastasis cell adhesion molecule/MUC18 increases prostate tumorigenesis in vivo and may affect the process by increasing proliferation, up-regulating the AKT survival pathway, and augmenting the angiogenic ability of prostate cancer cells.
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http://dx.doi.org/10.1016/j.juro.2010.11.052DOI Listing
April 2011

Comparative electrochemical and impedance studies of self-assembled rigid-rod molecular wires and alkanethiols on gold substrates.

Phys Chem Chem Phys 2010 Nov 4;12(44):14804-11. Epub 2010 Oct 4.

Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.

A study of the charge transfer and self-assembly characteristics of two new rigid-rod molecular wires 1 and 2 assembled on polycrystalline gold electrodes was carried out using electrochemical impedance spectroscopy and cyclic voltammetry. This class of wires have precisely controlled (ca. 1.5-2.5 nm) lengths of π-conjugation, with extended HOMO and LUMO wavefunctions. While rotations can occur around the C-C single bonds, the molecules cannot isomerise or fold due to their rigid backbone structures. The behaviour of these wires was compared with SAMs of heptanethiol (HPT) and dodecanethiol (DDT). It was found that SAMs of 1, which bears flexible hexyloxy sidechains, had randomly distributed pinholes which show microelectrode behaviour even when diluted with DDT. SAMs of 2, which do not have any sidechains, were well-organised at open-circuit potentials enabling evaluation of electron transfer kinetics assuming an average film thickness. However, impedance studies show that deviations from open circuit potentials resulted in an exponential decrease in charge transfer resistance, whereas capacitance remained constant, possibly attributable to conformational changes of the SAM. The syntheses and characterisation of the molecules is described.
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http://dx.doi.org/10.1039/c005402jDOI Listing
November 2010

[Preliminary study on effects of human brain-derived neurotrophic factor gene-modified bone marrow mesenchymal stem cells by intravenous transplantation on structure and function of rat injured spinal cord].

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2010 Aug;24(8):982-7

Department of Orthopedics, First Affiliated Hospital of Fujian Medical University, Fuzhou Fujian 350005, PR China.

Objective: To transplant intravenously human brain-derived neurotrophic factor (hBDNF) gene-modified bone marrow mesenchymal stem cells (BMSCs) marked with enhanced green fluorescent protein (EGFP) to injured spinal cord of adult rats, then to observe the viability of the cells and the expressions of the gene in spinal cord, as well as the influence of neurological morphological repairing and functional reconstruction.

Methods: Ninety-six male SD rats weighing (250 +/- 20) g were randomly divided into 4 groups: hBDNF-EGFP-BMSCs transplantation group (group A, n = 24), Ad5-EGFP-BMSCs transplantation group (group B, n = 24), control group (group C, n = 24), and sham operation group (group D, n = 24). In groups A, B, and C, the spinal cord injury models were prepared according to the modified Allen method at the level of T10 segment, and after 3 days, 1 mL hBDNF-EGFP-BMSCs suspension, 1 mL Ad5-EGFP-BMSCs suspension and 1 mL 0.1 mol/L phosphate buffered saline (PBS) were injected into tail vein, respectively; in group D, the spinal cord was exposed without injury and injection. At 24 hours after injury and 1, 3, 5 weeks after intravenous transplantation, the structure and neurological function of rats were evaluated by the Basso-Beattie-Bresnahan (BBB) score, cortical somatosensory evoked potential (CSEP) and transmission electron microscope. The viability and distribution of BMSCs in the spinal cord were observed by fluorescent inverted phase contrast microscope and the level of hBDNF protein expression in the spinal cord was observed and analyzed with Western blot. Meanwhile, the expressions of neurofilament 200 (NF-200) and synaptophysin I was analyzed with immunohi stochemistry.

Results: After intravenous transplantation, the neurological function was significantly improved in group A. The BBB scores and CSEP in group A were significantly higher than those in groups B and C (P < 0.05) at 3 and 5 weeks. The green fluorescence expressions were observed at the site of injured spinal cord in groups A and B at 1, 3, and 5 weeks. The hBDNF protein expression was detected after 1, 3, and 5 weeks of intravenous transplantation in group A, while it could not be detected in groups B, C, and D by Western blot. The expressions of NF-200 and synaptophysin I were stronger and stronger with transplanting time in groups A, B, and C. The expressions of NF-200 and synaptophysin I were strongest at 5 weeks, and the expressions in group A were stronger than those in groups B and C (P < 0.05). And the expressions of NF-200 in groups A, B, and C were significantly stronger than those in group D (P < 0.05), whereas the expressions of synaptophysin I in groups A, B, and C were significantly weaker than those in group D (P < 0.05). Ultramicrostructure of spinal cords in group A was almost normal.

Conclusion: Transplanted hBDNF-EGFP-BMSCs can survive and assemble at the injured area of spinal cord, and express hBDNF. Intravenous implantation of hBDNF-EGFP-BMSCs could promote the restoration of injured spinal cord and improve neurological functions.
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August 2010

Identifying diversity in nanoscale electrical break junctions.

J Am Chem Soc 2010 Jul;132(26):9157-64

Centre for Nanoscale Science and Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.

The realization of molecular-scale electronic devices will require the development of novel strategies for controlling electrical properties of metal/molecule/metal junctions, down to the single molecule level. Here, we show that it is possible to exert chemical control over the formation of metal/molecule...molecule/metal junctions in which the molecules interact by pi-stacking. The tip of an STM is used to form one contact, and the substrate the other; the molecules are conjugated oligophenyleneethynylenes (OPEs). Supramolecular pi-pi interactions allow current to flow through the junction, but not if bulky tert-butyl substituents on the phenyl rings prevent such interactions. For the first time, we find evidence that pi-stacked junctions can form even for OPEs with two thiol contacts. Furthermore, we find evidence for metal|molecule|metal junctions involving oligophenyleneethynylene monothiols, in which the second contact must be formed by the interaction of the pi-electrons of the terminal phenyl ring with the metal surface.
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http://dx.doi.org/10.1021/ja103327fDOI Listing
July 2010

Atrophy and dysfunction of parahippocampal white matter in mild Alzheimer's disease.

Neurobiol Aging 2012 Jan 1;33(1):43-52. Epub 2010 Apr 1.

Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA.

In addition to atrophy of mesial temporal lobe structures critical for memory function, white matter projections to the hippocampus may be compromised in individuals with mild Alzheimer's disease (AD), thereby compounding the memory difficulty. In the present study, high-resolution structural imaging and diffusion tensor imaging techniques were used to examine microstructural alterations in the parahippocampal white matter (PWM) region that includes the perforant path. Results demonstrated white matter volume loss bilaterally in the PWM in patients with mild AD. In addition, the remaining white matter had significantly lower fractional anisotropy and higher mean diffusivity values. Both increased mean diffusivity and volume reduction in the PWM were associated with memory performance and ApoE ε4 allele status. These findings indicate that, in addition to partial disconnection of the hippocampus from incoming sensory information due to volume loss in PWM, microstructural alterations in remaining fibers may further degrade impulse transmission to the hippocampus and accentuate memory dysfunction. The results reported here also suggest that ApoE ε4 may exacerbate PWM changes.
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http://dx.doi.org/10.1016/j.neurobiolaging.2010.01.020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2910843PMC
January 2012