Publications by authors named "Shan-Shan Zhao"

37 Publications

Gravitational Test beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole.

Phys Rev Lett 2020 Oct;125(14):141104

Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, People's Republic of China.

The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources.
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http://dx.doi.org/10.1103/PhysRevLett.125.141104DOI Listing
October 2020

The Anaerobic Product Ethanol Promotes Autophagy-Dependent Submergence Tolerance in .

Int J Mol Sci 2020 Oct 5;21(19). Epub 2020 Oct 5.

State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.

In response to hypoxia under submergence, plants switch from aerobic respiration to anaerobic fermentation, which leads to the accumulation of the end product, ethanol. We previously reported that autophagy-deficient mutants show increased sensitivity to ethanol treatment, indicating that ethanol is likely involved in regulating the autophagy-mediated hypoxia response. Here, using a transcriptomic analysis, we identified 3909 genes in Arabidopsis seedlings that were differentially expressed in response to ethanol treatment, including 2487 upregulated and 1422 downregulated genes. Ethanol treatment significantly upregulated genes involved in autophagy and the detoxification of reactive oxygen species. Using transgenic lines expressing fused to green fluorescent protein (), we confirmed that exogenous ethanol treatment promotes autophagosome formation in vivo. Phenotypic analysis showed that deletions in the alcohol dehydrogenase gene in mutants result in attenuated submergence tolerance, decreased accumulation of ATG proteins, and diminished submergence-induced autophagosome formation. Compared to the submergence-tolerant Arabidopsis accession Columbia (Col-0), the submergence-intolerant accession Landsberg (L) displayed hypersensitivity to ethanol treatment; we linked these phenotypes to differences in the functions of ADH1 and the autophagy machinery between these accessions. Thus, ethanol promotes autophagy-mediated submergence tolerance in Arabidopsis.
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http://dx.doi.org/10.3390/ijms21197361DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7583018PMC
October 2020

Multilocus genotyping of Giardia duodenalis in Bactrian camels (Camelus bactrianus) in China.

Parasitol Res 2020 Nov 2;119(11):3873-3880. Epub 2020 Oct 2.

College of Veterinary Medicine, Northwest A&F University, Yangling, 712100, Shaanxi Province, People's Republic of China.

The protozoan parasite Giardia duodenalis is known to infect humans and a wide range of animals globally. However, no studies on G. duodenalis infection in Bactrian camels have been reported. In the present study, in order to examine the prevalence and genetic diversity of G. duodenalis in Bactrian camels, 852 fecal samples were collected from 24 sampling sites in three geographical areas (Gansu province, Inner Mongolia, and Xinjiang Uygur autonomous regions) of northwestern China, and subjected to multilocus sequence typing (MLST) analysis targeting the 18S rRNA, β-giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi) genes. About 84 fecal samples tested positive for Giardia infection, with an overall prevalence of 9.8%, including three samples from camel calves with diarrhea. Significant differences (χ = 80.7, df = 2, P < 0.01) in the prevalence were found in Bactrian camels belonging to three geographical areas, with the highest (33.3%) in Gansu province and the lowest (4.2%) in Xinjiang Uygur autonomous region. Furthermore, significantly different prevalences (χ = 34.2, df = 2, P < 0.01) were revealed among age groups, with the highest (35.7%) in camels aged 3 to 6 years old, and the lowest (7.5%) in camels aged > 6 years old. Sequence analysis identified two assemblages, including zoonotic assemblage A and ungulate-adapted assemblage E, with the latter as the dominant G. duodenalis assemblage in each age group and at all sampling sites having positive samples except Hotan. Genetic variations were detected among G. duodenalis isolates in these camels, and eight, three, and seven haplotypes were identified at loci bg, gdh, and tpi, respectively, forming two multilocus genotypes (MLGs) of zoonotic assemblage A and one MLG of assemblage E. To the best of our knowledge, this is the first report on G. duodenalis infection in Bactrian camels, and the data indicate that G. duodenalis have a broad host range.
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http://dx.doi.org/10.1007/s00436-020-06905-yDOI Listing
November 2020

Multifaceted roles of RNA polymerase IV in plant growth and development.

J Exp Bot 2020 10;71(19):5725-5732

Vector-borne Virus Research Center, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Province Key Laboratory of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China.

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http://dx.doi.org/10.1093/jxb/eraa346DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7541909PMC
October 2020

Effects of CXCR7-neutralizing antibody on neurogenesis in the hippocampal dentate gyrus and cognitive function in the chronic phase of cerebral ischemia.

Neural Regen Res 2020 Jun;15(6):1079-1085

Department of Neurology, The First Hospital of China Medical University, Shenyang, Liaoning Province, China.

Stromal cell-derived factor-1 and its receptor CXCR4 are essential regulators of the neurogenesis that occurs in the adult hippocampal dentate gyrus. However, the effects of CXCR7, a new atypical receptor of stromal cell-derived factor-1, on hippocampal neurogenesis after a stroke remain largely unknown. Our study is the first to investigate the effect of a CXCR7-neutralizing antibody on neurogenesis in the dentate gyrus and the associated recovery of cognitive function of rats in the chronic stage of cerebral ischemia. The rats were randomly divided into sham, sham + anti-CXCR7, ischemia and ischemia + anti-CXCR7 groups. Endothelin-1 was injected in the ipsilateral motor cortex and striatum to induce focal cerebral ischemia. Sham group rats were injected with saline instead of endothelin-1 via intracranial injection. Both sham and ischemic rats were treated with intraventricular infusions of CXCR7-neutralizing antibodies for 6 days 1 week after surgery. Immunofluorescence staining with doublecortin, a marker for neuronal precursors, was performed to assess the neurogenesis in the dentate gyrus. We found that anti-CXCR7 antibody infusion enhanced the proliferation and dendritic development of doublecortin-labeled cells in the dentate gyrus in both ischemic and sham-operated rats. Spatial learning and memory functions were assessed by Morris water maze tests 30-32 days after ischemia. CXCR7-neutralizing antibody treatment significantly reduced the escape latency of the spatial navigation trial and increased the time spent in the target quadrant of spatial probe trial in animals that received ischemic insult, but not in sham operated rats. These results suggest that CXCR7-neutralizing antibody enhances the neurogenesis in the dentate gyrus and improves the cognitive function after cerebral ischemia in rats. All animal experimental protocols and procedures were approved by the Institutional Animal Care and Use Committee of China Medical University (CMU16089R) on December 8, 2016.
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http://dx.doi.org/10.4103/1673-5374.270416DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7034276PMC
June 2020

Enhancing the CRISPR/Cas9 system based on multiple GmU6 promoters in soybean.

Biochem Biophys Res Commun 2019 11 23;519(4):819-823. Epub 2019 Sep 23.

National Key Facilities for Crop Genetic Resources and Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China. Electronic address:

Small guide RNA (sgRNA) is an important component of the CRISPR/Cas9 system. The gene editing efficiency of the CRISPR/Cas9 system could be enhanced by using highly active U6 promoters to drive the expression of sgRNA. Therefore, we constructed various expression vectors based on the 11 GmU6 promoters predicted and cloned in the whole soybean genome. The expression of truncated GUS driven by 11 GmU6 promoters was tested in hairy roots and by Arabidopsis thaliana transformation. The results indicated that higher transcriptional levels were driven by 5 GmU6 promoters (GmU6-4, GmU6-7, GmU6-8, GmU6-10 and GmU6-11) in both soybean hairy roots and Arabidopsis thaliana. In addition, three genes, Glyma03g36470, Glyma14g04180 and Glyma06g136900, were selected as targets to detect the transcriptional levels of multiple GmU6 promoters. Mutations in these three genes were detected in soybean hairy roots after Agrobacterium rhizogenes infection, indicating efficient target gene editing, including nucleotide insertion, deletion, and substitution. Mutation efficiencies differed among the 11 GmU6 promoters, ranging from 2.8% to 20.6%, and markedly higher efficiencies were obtained with all three genes using the GmU6-8 (20.3%) and GmU6-10 (20.6%) promoters. These two GmU6 promoters also showed higher ability to drive truncated GUS transcription in both soybean hairy roots and transformed Arabidopsis thaliana. These results will help to construct an efficient CRISPR-Cas9 gene editing system and promote the application of the CRISPR-Cas9 genome editing system in soybean molecular breeding.
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http://dx.doi.org/10.1016/j.bbrc.2019.09.074DOI Listing
November 2019

Identification of duplicated suppressor of cytokine signaling 3 (SOCS3) genes in blunt snout bream (Megalobrama amblycephala).

Comp Biochem Physiol B Biochem Mol Biol 2020 Jan 14;239:110348. Epub 2019 Sep 14.

Genetics and Breeding Center for Blunt Snout Bream, Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:

The suppressor of cytokine signaling 3 (SOCS3) negatively regulates the responses of various immune cytokines. In this study, we identified socs3s genes of blunt snout bream. 209- and 216-aa long peptides are encoded by socs3a and socs3b genes, respectively. The socs3s mRNAs are expressed consistently during the entire process of embryonic development. Whole-mount in situ hybridization detected socs3a in the eyes and posterior somites at 12 h post fertilization (hpf), transcribed at the otic vesicle at 24 hpf, and transcribed at the eyes, brain, and otic vesicle at 36 hpf; while the socs3b mRNA was transcribed at the notochord at 12 hpf, expressed in the brain, eyes, and tailbud at 24 hpf, and detected in the brain at 36 hpf. The expression of socs3a is slightly different from that of socs3b in tissues of juvenile and adult blunt snout bream. After recombinant human growth hormone (hGH) treatment, the transcript levels of socs3s of blunt snout bream were increased in gills, spleen, kidney, and gonads. After Aerononas hydrophila infection, the mRNA levels of socs3s of blunt snout bream were significantly increased in the liver, spleen, intestine, and kidney tissues. Blunt snout bream were susceptible to various pathogenic microorganisms, we intraperitoneally injected blunt snout bream with A. hydrophila to explore the immune mechanism of socs3s. These results suggested that socs3s of blunt snout bream plays important roles in the regulation of embryonic development and tissue growth, and that socs3s may also play key roles in regulating the bacterial-induced congenital immune response. Socs3s genes has the potential to be used as targeted genes to improve the immunity against bacteria, which is conducive to the improvement of production and breeding.
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http://dx.doi.org/10.1016/j.cbpb.2019.110348DOI Listing
January 2020

Identification and Differentiation of Radix and Radix Preaparata through the Quantitative Analysis of Multicomponents by the Single-Marker Method.

J Anal Methods Chem 2019 8;2019:7430717. Epub 2019 Aug 8.

National Institute for Food and Drug Control, Beijing 100050, China.

The quantitative analysis of multicomponents by the single-marker (QAMS) method was established and the relationship between value (the ratio of the sum of the contents of emodin-8-O--D-glucopyranoside and physcion-8-O--D-glucopyranoside to the sum of the contents of emodin and physcion) and the steaming time was found to identify and differentiate Radix and its processed product. Emodin was considered as the control substance, and the correction factors of physcion, emodin-8-O--D-glucopyranoside, and physcion-8-O--D-glucopyranoside were computed. In addition, the contents of the four components were determined. When the value is greater than or equal to 1.0, the sample was identified as Radix, and if the value was between 0.6 and 1.0, the sample of Radix Preaparata was processed incompletely. The value of the qualified Radix should be no more than 0.6. However, the influence of different sample injection volumes and the chromatographic columns and instruments used on the durability of the correction factors and RSD ≤3% hindered accurate identification; therefore, a QAMS method using an external standard value with methodological verification was developed. We redefined the " rules." The method using " rules" revised after optimization of the determination results was used, as it was accurate and led to convenient operation and low inspection costs, and moreover, the method could differentiate Radix Preaparata and Radix medicinal samples and precisely identify samples that were different from the completely processed product Radix Preaparata.
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http://dx.doi.org/10.1155/2019/7430717DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6702820PMC
August 2019

Functional conservation and divergence of duplicated the suppressor of cytokine signaling 1 in blunt snout bream (Megalobrama amblycephala).

Gen Comp Endocrinol 2019 12 10;284:113243. Epub 2019 Aug 10.

Genetics and Breeding Center for Blunt Snout Bream, Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Huchenghuan Road 999, Shanghai 201306, China. Electronic address:

The suppressor of cytokine signaling 1 (SOCS1) is an essential feedback regulator extensively involved in many different cytokine signaling pathways, such as regulation of the immune system and growth of organism. However, the molecular and functional information on socs1 genes in freshwater fish is unclear. In the present paper, we identified and characterized the full-length closely related but distinct socs1 genes (socs 1a and -1b) in blunt snout bream (Megalobrama amblycephala). The bioinformatic analysis results showed that duplicated socs1s shared majority conserved motifs with other vertebrates. Both socs1a and -1b mRNAs were detected throughout embryogenesis, and gradually increase and then constantly expressed after 16 hpf. Whole-mount in situ hybridization demonstrated that socs1a and socs1b mRNAs were detected in the brain at 12hpf and 24hpf, and in the notochord and brain at 36hpf. In adult fish, the socs1a mRNA were strongly expressed in the heart, eye, kidney, spleen and gonad, but were found to be relatively low in the intestine and liver. On the other hand, the expression of socs1b mRNA was significantly high in the muscle, eye and spleen, and relatively low in the intestine, liver, skin and heart. The results of hGH treatment experiment showed that socs1a and 1b mRNAs were upregulated markedly in the kidney, muscle and liver. Overexpression of socs1s significantly inhibit the GH and JAK/STAT factor stat3 and the inhibitory effect of SOCS1s on GH may be involved in JAK-STAT signaling pathway. These results indicate that SOCS1 plays an important role in regulating growth and development.
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http://dx.doi.org/10.1016/j.ygcen.2019.113243DOI Listing
December 2019

Alternative splicing and translation play important roles in hypoxic germination in rice.

J Exp Bot 2019 02;70(3):817-833

State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Taian, Shandong, China.

Post-transcriptional mechanisms (PTMs), including alternative splicing (AS) and alternative translation initiation (ATI), may explain the diversity of proteins involved in plant development and stress responses. Transcriptional regulation is important during the hypoxic germination of rice seeds, but the potential roles of PTMs in this process have not been characterized. We used a combination of proteomics and RNA sequencing to discover how AS and ATI contribute to plant responses to hypoxia. In total, 10 253 intron-containing genes were identified. Of these, ~1741 differentially expressed AS (DAS) events from 811 genes were identified in hypoxia-treated seeds compared with controls. Over 95% of these were not present in the list of differentially expressed genes. In particular, regulatory pathways such as the spliceosome, ribosome, endoplasmic reticulum protein processing and export, proteasome, phagosome, oxidative phosphorylation, and mRNA surveillance showed substantial AS changes under hypoxia, suggesting that AS responses are largely independent of transcriptional regulation. Considerable AS changes were identified, including the preferential usage of some non-conventional splice sites and enrichment of splicing factors in the DAS data sets. Taken together, these results not only demonstrate that AS and ATI function during hypoxic germination but they have also allowed the identification of numerous novel proteins/peptides produced via ATI.
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http://dx.doi.org/10.1093/jxb/ery393DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6363088PMC
February 2019

Analysis of the Effect of Co- Irradiation Sterilization Technology on the Chemical Composition of Saffron Using UPLC and UPLC/Q-TOF-MS.

J Anal Methods Chem 2018 4;2018:2402676. Epub 2018 Mar 4.

National Institutes for Food and Drug Control, Beijing, China.

To evaluate the effect of Co-γ irradiation sterilization technology on the chemical composition of saffron, we collected 10 batches of saffron samples and treated them with different irradiation doses. UPLC characteristic chromatogram showed that there was no significant effect of irradiation on 13 common peak areas. The results of cluster analysis and principal component analysis showed that there were no differences in the chemical composition in nonirradiated and irradiated samples. UPLC/Q-TOF-MS identified 40 characteristic components of saffron, and the results showed that all of these were detected in the saffron samples both with and without irradiation. Irradiation doses at or below 10 kGy had no significant effect on the chemical components of saffron. This provides a sound basis for the use of Co-γ ray irradiation sterilization technology during the preparation of original powder saffron as a medicinal herb, for the effective destruction of mycotoxin contamination.
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http://dx.doi.org/10.1155/2018/2402676DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5857329PMC
March 2018

Impaired decision-making and functional neuronal network activity in systemic lupus erythematosus.

J Magn Reson Imaging 2018 12 14;48(6):1508-1517. Epub 2018 Mar 14.

First Affiliated Hospital of Shantou University Medical College, Shantou, China.

Background: Systemic lupus erythematosus (SLE) is associated with cognitive deficit but the exact neural mechanisms remain unclear.

Purpose: To explore sequential brain activities using functional magnetic resonance imaging (fMRI) during the performance of a decision-making task, and to determine whether serum or clinical markers can reflect the involvement of the brain in SLE.

Subjects: Sixteen female SLE patients without overt clinical neuropsychiatric symptoms and 16 healthy controls were included.

Field Strength/sequence: 1.5T, T -weighted anatomic images, gradient-echo echo-planar imaging sequence, and 3D images.

Assessment: The computer-based Iowa Gambling Task (IGT) for assessing decision-making was performed by SLE patients and 16 matched controls; brain activity was recorded via blood oxygen level-dependent (BOLD) fMRI. The amplitudes of the average BOLD responses were calculated for each individual subject, and activation data from fMRI experiments were compared between the two groups.

Statistical Tests: Two-sample t-test; repeated-measures analysis of variance (ANOVA); linear regression analyses.

Results: Imaging revealed activity in a distributed network of brain regions in both groups, including the ventromedial prefrontal cortex (vmPFC), the orbitofrontal cortex (OFC), the dorsolateral prefrontal cortex (dlPFC), the anterior cingulate cortex (ACC), the posterior cingulate cortex (PCC), and the striatum, as well as the insular, parietal, and occipital cortices. Compared to controls, SLE patients showed lower activation in a convergence zone and the limbic system, namely, the OFC, vmPFC, ACC, and PCC, but greater activation in memory, emotion, and behavior systems involving the dlPFC, the insular cortex and the striatum. Furthermore, brain activation in the vmPFC was positively correlated with IGT scores (r = 0.63, P < 0.001), but inversely related to disease activity (r = -0.57, P < 0.01).

Data Conclusion: The dynamics among the aforementioned neural systems (some hyperfunctioning, others hypofunctioning) may shed some light on the pathologic mechanisms underlying SLE without overt clinical neuropsychiatric symptoms. In addition, disease activity may potentially be used as an effective biomarker reflecting cerebral involvement in SLE.

Level Of Evidence: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;48:1508-1517.
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http://dx.doi.org/10.1002/jmri.26006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6282848PMC
December 2018

Morphological and molecular divergence of Rhipicephalus turanicus tick from Albania and China.

Exp Appl Acarol 2017 Dec 27;73(3-4):493-499. Epub 2017 Nov 27.

School of Medicine, Shihezi University, Shihezi, 832002, Xinjiang Uygur Autonomous Region, People's Republic of China.

Rhipicephalus turanicus is an important tick species potentially carrying tick-borne pathogens. Several tick species have obvious subspecies divergence. However few studies aimed to examine the existence of divergence within R. turanicus. Therefore, a detailed morphological and molecular analysis was conducted for comparing R. turanicus from the Mediterranean Basin (represented by Albania) and Central Asia (Northwestern China). Altogether 315 adult ticks of R. turanicus (103 from Albania and 212 from China) were morphologically and molecularly analysed. DNA samples were used for mitochondrial 16S rRNA and cox1 gene sequences analysis. In addition, as potentially genetic markers, three fragments including partial nad1-16S rRNA, nad2-cox1, cox1-tRNA-Lys, were designed and then phylogenetically analyzed. Based on detailed morphological observations, only basis capituli length:width ratio (females), the length, the width and the length:width ratio of the scutum (males) had differences between R. turanicus from China and Albania. Gene divergences of 16S rRNA, cox1, partial nad1-16S rRNA, nad2-cox1 and cox1-tRNA-Lys from China and Albania ticks were 3.53-4.84, 3.57-4.92, 3.57-4.07, 3.57-4.39 and 3.18-4.69%, respectively. The evaluated five genetic markers revealed two phylogenetic branches in R. turanicus. Obvious differences exist within R. turanicus based on morphological and genetic analysis. Three newly designed genetic markers (partial nad1-16S rRNA, nad2-cox1 and cox1-tRNA-Lys) in this study may be suitable genetic tools for identification and analysis in R. turanicus. Subspecies analysis of R. turanicus from other regions of the world should be initiated in the future.
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http://dx.doi.org/10.1007/s10493-017-0189-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5727151PMC
December 2017

2D Frameworks Self-assembled From a Hydrazone Ligand and Azide Salts: Synthesis, Structures, and Luminescent Property.

Acta Chim Slov 2017 06;64(2):431-437

Three metal-organic coordination polymers [Cu(L)(N3)]·(H2O)0.25n (1), [Zn(L)(N3)]·(H2O)0.5n (2) and [Cd2(L)2(N3)2(H2O)]n (3) have been synthesized from hydrazone ligand N'-(1-(pyrazin-2-yl)ethylidene)isonicotinohydrazide (HL), NaN3 and corresponding metal nitrates. Complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. All three complexes feature 2D coordination network in which L1- acts as NNON tetradentate ligand and azide acts as end-on bridging ligand. In complexes 1 and 2, only intra-sheet hydrogen bonding interactions are found, while the hydrogen bonding interactions between water molecules and host framework result in 3D network for 3. In addition, complexes 2 and 3 exhibited intense fluorescent emissions in the solid state at room temperature.
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http://dx.doi.org/10.17344/acsi.2017.3268DOI Listing
June 2017

HIV-1 p55-gag protein induces senescence of human bone marrow mesenchymal stem cells and reduces their capacity to support expansion of hematopoietic stem cells in vitro.

Cell Biol Int 2017 Sep 19;41(9):969-981. Epub 2017 Jul 19.

College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China.

Patients with human immunodeficiency virus-1 (HIV-1) infection often present with hematopoietic failure. As the important hematopoietic support cells in the bone marrow (BM), the BM mesenchymal stem cells (BMSCs) can be impacted by HIV proteins that are released by infected cells within BM. In this study, we tested whether HIV protein p55-gag could induce senescence of BMSCs and reduce their capacity to support expansion of hematopoietic stem cells in vitro. BMSCs were chronically treated with p55-gag (BMSC ) for up to 20 days, and their proliferative activity and senescence makers were compared to nontreated cells (BMSC ). Then, we analyzed the hematopoietic support function of BMSC and BMSC by determining cellular proliferation, colony-forming ability, and primitive hematopoietic populations of hematopoietic progenitors grown on the BMSCs. In addition, we compared the gene expression patterns for supporting hematopoiesis of BMSC and BMSC The results show that when compared to BMSC , BMSC reduced their proliferative activity and underwent senescence. The ability of BMSC to support the expansion of committed hematopoietic progenitors from umbilical cord blood-derived CD34 cells may be impaired, while the expression of genes associated with maintaining and enhancing hematopoiesis appeared to be decreased in treated BMSCs compared to control BMSCs. In conclusion, senescence induced by p55-gag resulted in decreased hematopoietic support function of BMSCs through reducing a series of hematopoietic cytokine expression.
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http://dx.doi.org/10.1002/cbin.10791DOI Listing
September 2017

Preparations, characterization, and biological features of mononuclear Cu(II) complexes based on hydrazone ligands.

Bioorg Med Chem Lett 2016 10 7;26(20):4925-4929. Epub 2016 Sep 7.

School of Life Sciences, Shandong University of Technology, Zibo 255000, PR China; State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, PR China.

Three mononuclear Cu(II) complexes Cu(HL)Cl (1), Cu(HL)Cl (2), and Cu(L)SCN (3) have been synthesized based on chelating hydrazone ligands HL, HL, and HL, respectively. These new compounds gave satisfactory IR-spectroscopic data and were further characterized by elemental and X-ray diffraction analyses. Their urease inhibitory evaluation was tested in vitro against jack bean urease. The results showed that the inhibitory activities of the copper complexes are all superior to the positive reference. Enzyme kinetics studies were undertaken to estimate the inhibition mechanism of the copper complexes. Molecular docking simulations have been performed to rationalize their binding models. In addition, their interactions with serum albumin were also studied.
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http://dx.doi.org/10.1016/j.bmcl.2016.09.015DOI Listing
October 2016

First detection of Candidatus Rickettsia barbariae in the flea Vermipsylla alakurt from north-western China.

Parasit Vectors 2016 06 7;9(1):325. Epub 2016 Jun 7.

School of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, 832000, China.

Background: Vermipsylla is a genus of the family Vermipsyllidae within the order Siphonaptera of fleas. Vermipsylla alakurt is mainly distributed in alpine pastoral areas of Kazakhstan, Mongolia, China and Nepal, and infests sheep, yaks and horses, causing irritation, poor condition, anaemia and even death. However, to date, no rickettsial agents have been reported in V. alakurt.

Findings: A total of 133 fleas were collected directly from the tails of three sheep flocks (n = 335) in Minfeng County, Xinjiang Uygur Autonomous Region, north-western China. Of these, 55 fleas were identified by morphological examination and molecular analysis of four loci (the ribosomal 18S and 28S rDNA genes and the mitochondrial genes cytochrome  c oxidase subunit II and elongation factor 1-alpha). Eight Rickettsia-specific gene fragments originated from seven genes: the 17-kilodalton antigen gene (17-kDa), citrate synthase gene (gltA), 16S rRNA gene (rrs), outer membrane protein A gene (ompA), surface cell antigen 1 gene (sca1), PS120 protein gene (gene D), and outer membrane protein B gene (ompB, two fragments), were used to identify the species of Rickettsia in 53 fleas. The amplified products were sequenced and included in a phylogenetic analysis to verify the taxonomic identification of the rickettsial agents. Based on morphological and molecular evidence, the flea was identified as Vermipsylla alakurt. Nine samples were positive (16.98 %, 9/53) for Rickettsia spp. The phylogenetic tree revealed that the rickettsial agents found in V. alakurt cluster with Candidatus Rickettsia barbariae.

Conclusions: Our study suggests that: (i) V. alakurt may serve as a carrier for Candidatus R. barbariae; and (ii) Candidatus R. barbariae, previously reported in Israel, is the eighth newly discovered validated Rickettsia species in China. This finding extends our knowledge of the distribution of Candidatus R. barbariae and the profile of carriers, which not only comprise ticks but also fleas.
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http://dx.doi.org/10.1186/s13071-016-1614-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4895814PMC
June 2016

Synthesis, crystal structures, molecular docking, and urease inhibitory activity of transition metal complexes with 2-[4-(4-fluorophenyl)piperazin-1-yl]acetic acid.

Acta Chim Slov 2016 ;63(1):165-72

Two novel mononuclear complexes, [Cu(L)(2)(H(2)O)]·(2)H(2)O (1) and [Ni(L)(2)(H(2)O)(2)] (2) (HL = 2-[4-(4-fluorophenyl)piperazin-1-yl]acetic acid) were synthesized and structurally determined by single-crystal X-ray diffraction. Their inhibitory activities were tested in vitro against jack bean urease. Molecular docking was investigated to determine the probable binding mode. The experimental values and docking simulation exhibited that complex 1 had better inhibitory activity than the positive reference aceto hydroxamic acid (AHA), showing IC(50) value of 0.15 ± 0.08 µM, while 2 showed no inhibitory activity.
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http://dx.doi.org/10.17344/acsi.2015.2109DOI Listing
June 2016

Synthesis, Structural Diversity and Mimic Superoxide Dismutase of Mn(II) Complexes Derived from N, O-donor Schiff bases.

Acta Chim Slov 2016 ;63(1):55-61

Two new potentially tetradentate Schiff base ligands N'-(pyridin-2-ylmethylene)nicotinohydrazide (L1), and N'-(pyridin-2-ylmethylene)isonicotinohydrazide (L(2)) were synthesized. Reactions of hydrazone ligands L(1) and L(2) with Mn(NO(3))(2) afford two mononuclear Mn(II) complexes, [Mn(L(1))(NO(3))(H(2)O)(2)]•(NO(3)) (1) and [Mn(L(2))(2)(NO(3))(H(2)O)]•(NO(3)) (2). For complexes 1 and 2, L(1) and L(2) act as pincer-like tridentate or bidentate ligands, respectively. The Mn(II) ions in the two compounds are both in heptacoordinated environment, while the two molecules display diverse solid-state supramolecular structures because of the different orientation of Npyridine and hydrogen bonding patterns of nitrate anions. Complex 1 features 2D supramolecular sheet, while complex 2 is double-chain supramolecular structure. Both of the two complexes exhibit moderate superoxide dismutase (SOD) mimetic activity.
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http://dx.doi.org/10.17344/acsi.2015.1918DOI Listing
June 2016

Puerarin attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice.

Neurotoxicology 2015 Dec 25;51:166-71. Epub 2015 Oct 25.

Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, People's Republic of China; Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China, 76# West Yanta Road, Xi'an 710061, Shaanxi, People's Republic of China. Electronic address:

Puerarin (PUE), an isoflavone purified from the root of Pueraria lobata (Chinese herb), has been reported to attenuate learning and memory impairments in the transgenic mouse model of Alzheimer's disease (AD). In the present study, we tested PUE in a sporadic AD (SAD) mouse model which was induced by the intracerebroventricular injection of streptozotocin (STZ). The mice were administrated PUE (25, 50, or 100mg/kg/d) for 28 days. Learning and memory abilities were assessed by the Morris water maze test. After behavioral test, the biochemical parameters of oxidative stress (glutathione peroxidase (GSH-Px), superoxide dismutases (SOD), and malondialdehyde (MDA)) were measured in the cerebral cortex and hippocampus. The SAD mice exhibited significantly decreased learning and memory ability, while PUE attenuated these impairments. The activities of GSH-Px and SOD were decreased while MDA was increased in the SAD animals. After PUE treatment, the activities of GSH-Px and SOD were elevated, and the level of MDA was decreased. The middle dose PUE was more effective than others. These results indicate that PUE attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice. PUE may be a promising therapeutic agent for SAD.
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http://dx.doi.org/10.1016/j.neuro.2015.10.010DOI Listing
December 2015

L-carnosine inhibits neuronal cell apoptosis through signal transducer and activator of transcription 3 signaling pathway after acute focal cerebral ischemia.

Brain Res 2013 Apr 27;1507:125-33. Epub 2013 Feb 27.

Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, No. 3 Kangfuqian Street, Zhengzhou, 450052 Henan, China.

Considerable studies have showed that L-carnosine provides anti-oxidative and anti-apoptotic roles in the animal models of global or focal cerebral ischemia. However, the anti-apoptotic mechanisms of L-carnosine in the focal cerebral ischemia model have yet to be elucidated. To investigate the molecular mechanisms, rat models of permanent middle cerebral artery occlusion (pMCAO) and sham operation were first established and then pMCAO and sham-operated rats were treated with L-carnosine or vehicle alone. After this treatment, neurological deficits were evaluated at 12, 24 and 72 h after operation and the infarct volume was measured at 72 h after treatment. In addition, we also detected the mRNA expression of signal transducer and activator of transcription 3 (STAT3) and Pim-1 and the protein expression of phosphorylated STAT3, Pim-1, bcl-2 and cleaved caspase-3 at 12, 24 and 72 h post-pMCAO. Our results showed that the L-carnosine-treated rats had milder neurological deficits and smaller infarct volume and showed up-regulated expression in mRNA levels of STAT3 and Pim-1 than vehicle-treated rats at 72 h after treatment. Meanwhile, compared with vehicle-treated rats, the L-carnosine-treated rats exhibited higher protein expressions of pSTAT3, Pim-1 and bcl-2 but lower expression of cleaved caspase-3 protein at 72 h following operation. These results indicate that L-carnosine plays an important role in inhibiting neuronal cell apoptosis through STAT3 signaling pathway after acute cerebral ischemia.
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http://dx.doi.org/10.1016/j.brainres.2013.02.032DOI Listing
April 2013

Molecular and supra-molecular structure of waxy starches developed from cassava (Manihot esculenta Crantz).

Carbohydr Polym 2013 Feb 27;92(2):1451-62. Epub 2012 Oct 27.

UR1268 Biopolymères Interactions Assemblages, INRA, F-44300 Nantes, France.

The aim of this work was to characterize the amylopectin of low amylose content cassava starches obtained from transgenesis comparatively with a natural waxy cassava starch (WXN) discovered recently in CIAT (International Center for Tropical Agriculture). Macromolecular features, starch granule morphology, crystallinity and thermal properties of these starches were determined. M¯(w) of amylopectin from the transgenic varieties are lower than WXN. Branched and debranched chain distributions analyses revealed slight differences in the branching degree and structure of these amylopectins, principally on DP 6-9 and DP>37. For the first time, a deep structural characterization of a series of transgenic lines of waxy cassava was carried out and the link between structural features and the mutated gene expression approached. The transgenesis allows to silenced partially or totally the GBSSI, without changing deeply the starch granule ultrastructure and allows to produce clones with similar amylopectin as parental cassava clone.
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http://dx.doi.org/10.1016/j.carbpol.2012.10.048DOI Listing
February 2013

Development of waxy cassava with different Biological and physico-chemical characteristics of starches for industrial applications.

Biotechnol Bioeng 2011 Aug 11;108(8):1925-35. Epub 2011 Mar 11.

National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.

The quality of cassava starch, an important trait in cassava breeding programs, determines its applications in various industries. For example, development of waxy (having a low level of amylose) cassava is in demand. Amylose is synthesized by granule-bound starch synthase I (GBSSI) in plants, and therefore, down-regulation of GBSSI expression in cassava might lead to reduced amylose content. We produced 63 transgenic cassava plant lines that express hair-pin dsRNAs homologous to the cassava GBSSI conserved region under the control of the vascular-specific promoter p54/1.0 from cassava (p54/1.0::GBSSI-RNAi) or cauliflower mosaic virus (CaMV) 35S (35S::GBSSI-RNAi). After the screening storage roots and starch granules from field-grown plants with iodine staining, the waxy phenotype was discovered: p54/1.0::GBSSI-RNAi line A8 and 35S::GBSSI-RNAi lines B9, B10, and B23. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that there was no detectable GBSSI protein in the starch granules of plants with the waxy phenotype. Further, the amylose content of transgenic starches was significantly reduced (<5%) compared with the level in starch granules from the wild-type (about 25%). The inner structure of the waxy starch granules differed from that of the untransformed ones, as revealed by transmission electron microscopy analysis as well as morphological changes in the iodine-starch complex. Endothermic enthalpy was reduced in waxy cassava starches, according to differential scanning calorimeter analysis. Except B9, all waxy starches displayed the A-type X-ray diffraction pattern. Amylogram patterns of the waxy cassava starches were analyzed using a rapid viscosity analyzer and found to have increased values for clarity, peak viscosity, gel breakdown, and swelling index. Setback, consistency, and solubility were notably reduced. Therefore, waxy cassava with novel starch in its storage roots was produced using the biotechnological approach, promoting its industrial utilization.
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http://dx.doi.org/10.1002/bit.23120DOI Listing
August 2011

The therapeutic efficacy of conjugated linoleic acid - paclitaxel on glioma in the rat.

Biomaterials 2010 Aug;31(22):5855-64

Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.

Considering the effects of conjugated linoleic acid (CLA) on anti-tumor and anti-angiogenic in brain tumor, synergistic anti-tumor activity with taxane as well as potential activity for transporting chemotherapeutic agents across the blood-brain barrier (BBB), the purpose of this study was to synthesize CLA-paclitaxel (CLA-PTX) conjugate which could reach to the brain tissue and target brain tumor. The CLA was covalently linked to PTX. The conjugate was stable in PBS and rat plasma in vitro and had no microtubule assembly activity in solution and slight effect of arresting cell cycle progression at the G(2)-M phase. The in vitro cytotoxicity of conjugate was lower than that of PTX (p < 0.05). The conjugate showed higher cellular uptake efficiency on C6 glioma cells. The entire pharmacokinetic index revealed the significant enhancement of the conjugate pharmacokinetics compared with that in PTX (p < 0.01). The conjugate, unlike PTX, could distribute in brain tissue and retained higher concentrations throughout 360 h. The anti-tumor efficacy in brain tumor-bearing rats after administering conjugate was significantly higher than that after giving Taxol (p < 0.01). In conclusion, this CLA-PTX conjugate showed great potential to become a new prodrug of PTX and the methodology can be applied to other anticancer drugs.
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http://dx.doi.org/10.1016/j.biomaterials.2010.03.079DOI Listing
August 2010

2,7-Dibromo-9,9-bis-[(pyridin-1-ium-4-yl)meth-yl]fluorene dinitrate.

Acta Crystallogr Sect E Struct Rep Online 2010 Jan 9;66(Pt 2):o251. Epub 2010 Jan 9.

In the title compound, C(25)H(20)Br(2)N(2) (2+)·2NO(3) (-), the cation lies on a twofold rotation axis which imposes disorder of the dibromo-fluorene unit. In addition, the unique nitrate anion is disordered over two general sites of equal occupancy. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds.
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http://dx.doi.org/10.1107/S1600536809054828DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2979851PMC
January 2010

Improving the accuracy of low level quantum chemical calculation for absorption energies: the genetic algorithm and neural network approach.

Phys Chem Chem Phys 2009 Jul 23;11(25):5124-9. Epub 2009 Mar 23.

Institute of Functional Material Chemistry, Northeast Normal University, Changchun, Jilin, China.

The combination of genetic algorithm and back-propagation neural network correction approaches (GABP) has successfully improved the calculation accuracy of absorption energies. In this paper, the absorption energies of 160 organic molecules are corrected to test this method. Firstly, the GABP1 is introduced to determine the quantitative relationship between the experimental results and calculations obtained by using quantum chemical methods. After GABP1 correction, the root-mean-square (RMS) deviations of the calculated absorption energies reduce from 0.32, 0.95 and 0.46 eV to 0.14, 0.19 and 0.18 eV for B3LYP/6-31G(d), B3LYP/STO-3G and ZINDO methods, respectively. The corrected results of B3LYP/6-31G(d)-GABP1 are in good agreement with experimental results. Then, the GABP2 is introduced to determine the quantitative relationship between the results of B3LYP/6-31G(d)-GABP1 method and calculations of the low accuracy methods (B3LYP/STO-3G and ZINDO). After GABP2 correction, the RMS deviations of the calculated absorption energies reduce to 0.20 and 0.19 eV for B3LYP/STO-3G and ZINDO methods, respectively. The results show that the RMS deviations after GABP1 and GABP2 correction are similar for B3LYP/STO-3G and ZINDO methods. Thus, the B3LYP/6-31G(d)-GABP1 is a better method to predict absorption energies and can be used as the approximation of experimental results where the experimental results are unknown or uncertain by experimental method. This method may be used for predicting absorption energies of larger organic molecules that are unavailable by experimental methods and by high-accuracy theoretical methods with larger basis sets. The performance of this method was demonstrated by application to the absorption energy of the aldehyde carbazole precursor.
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http://dx.doi.org/10.1039/b812492bDOI Listing
July 2009

[Effect of doxycycline on the development of pulmonary hypertension induced by four methods in rats].

Zhonghua Er Ke Za Zhi 2009 Apr;47(4):260-4

Department of Pediatric Cardiology, West China Second Hospital, Sichuan University, Chengdu 610041, China.

Objective: Based on establishment of four rat models of experimental pulmonary hypertension (PH), the authors examined the inhibition of matrix metalloproteinases (MMPs) by doxycycline and its effect on the development of PH and associated pulmonary vascular remodeling.

Method: Healthy male Sprague-Dawley rats (weight 350 g to 400 g) were randomly divided into nine groups: Normal control group (N), four model groups (H, M, P, PM) and their corresponding drug intervention groups (HD, MD, PD, PMD) in which doxycycline was given by gavage at a 20 mg/kg daily dosage. On day 28 (day 35 for PM and PMD models), the animals were catheterized to record mean pulmonary arterial pressure (mPAP) and then sacrificed. Fulton Index [RV/(LV + S)] was measured immediately. Morphometric parameters, including percent vascular wall thickness and muscularization of non-muscularized peripheral pulmonary arterioles were determined microscopically. The activity of MMPs was measured by gelatin zymography in the lung tissue.

Results: (1) Rats in all model groups (H, M, P, PM) developed significant pulmonary arterial hypertension and right ventricular hypertrophy in comparison with their corresponding drug intervention groups (HD, MD, PD, PMD) and normal control group (N) (P < 0.01). For example, mPAP (mm Hg)(1 mm Hg = 0.133 kPa):N: 18.10 +/- 1.45, H: 27.20 +/- 1.55, HD: 23.90 +/- 2.13; Fulton Inedx(%):N: 23.41 +/- 1.84, H: 34.44 +/- 2.70, HD: 27.55 +/- 2.45. (2) The percent vascular wall thickness (WT%) and percentage of muscularization of non-muscular pulmonary arterioles were significantly increased in all model groups compared with drug intervention groups and normal group (P < 0.01). For example, WT%:N: 10.90 +/- 3.11, H:41.41 +/- 5.21, HD: 17.73 +/- 3.12; Muscularization(%):N: 13.83 +/- 3.72, H: 44.93 +/- 2.43, HD: 29.89 +/- 4.45. (3) The activity of MMPs was inhibited by doxycycline effectively as assessed by gelatin zymography (P < 0.01). For example, the activity of MMP2 (A x 10(3)):N: 1.43 +/- 0.24, H: 3.58 +/- 0.28, HD: 2.29 +/- 0.31.

Conclusion: Doxycycline attenuated PH and associated pulmonary vascular remodeling in all rat PH models. The study suggests that high expression and enhanced activity of MMPs may play a brutial role in the development of PH. Such phenomenon seems to be common in a variety of PH models of different etiology.
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April 2009

[Changes of MMP-2,9 and TIMP-1 expressions in rats with pulmonary arterial hypertension after captopril and losartan interventions].

Sichuan Da Xue Xue Bao Yi Xue Ban 2009 Mar;40(2):255-9

Department of Padiatric Cardiology, West China Second Hospital, Sichuan University, Chengdu 610041, China.

Objective: To determine the effect of captopril and losartan on the expressions of matrix metalloproteinase-2,9 (MMP-2,9) and metalloproteinase-1 (TIMP-1) in rats with pulmonary arterial hypertension, and the mechanisms of captopril and losartan in intervening the development of pulmonary arterial hypertension.

Methods: Forty male Spraque-Dawley rats were divided into 4 groups randomly: pulmonary arterial hypertension (created by pneumonectomy plus MCT injection) model group (PAH Model), PAH model treated with captopril [PAH+Cap 10 mg/(kg x d)], losartan group [PAH+Los 15 mg/(kg x d)] and normal control group(Control). The mPAP, weight ratio of RV to LV+S, neointima formation, relative thickness of small pulmonary arteries, and degree of muscularization of non-muscular arterioles were measured at day 35. The expression of SM-a-actin in the PASMC was determined by immunochemistry stain. The expressions of MMP-2, 9, TIMP-1 and MMP-2, 9, TIMP-1 mRNA in the pulmonary tissues were determined by immunohistochemistry and FQ-PCR respectively. The enzymatic activity of MMP-2, 9 was measured by Gelatin zymography.

Results: Pneumonectomy plus MCT injection induced severe pulmonary arterial hypertension characterized by neointimal formation. Captopril or losartan suppressed the increase of mPAP, right ventricle weight, thickness of small pulmonary arteries and muscularization of peripheral pulmonary arterioles in the rats with PAH (P < 0.05). The PAH model group had higher expressions of MMP-2, 9, TIMP-1 mRNA and enzymatic activity of MMP-2, 9 in lung tissue than the other groups (P < 0.05). Captopril intervention had similar effects as losartan intervention.

Conclusion: The captopril and losartan induced attenuation of PAH and pulmonary vascular remodeling is likely to be associated with the regulation of the expressions of MMP-2, 9, TIMP-1.
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March 2009

Effect of H2O2/HCl heat treatment of implants on in vivo peri-implant bone formation.

Int J Oral Maxillofac Implants 2008 Nov-Dec;23(6):1020-8

Department of Oral and Maxillofacial Surgery, Stomatology Hospital, School of Medicine, Zhejiang University, Yan'an Road, Hangzhou, China.

Purpose: To investigate the effect of H2O/HCl heat treatment on peri-implant bone formation in vivo.

Materials And Methods: Twenty Ti-6Al-4V implants and 30 Ti-6Al-4V discs were used in this study. The implants and discs were separated into 2 groups: sandblasted and dual acid-etched group (control group) and sandblasted, dual acid-etched and H2O2/HCl heat-treated group (test group). Surface morphology, roughness, and crystal structure of the discs were analyzed by field-emission scanning electron microscopy, atomic force microscopy, and low angle X-ray diffractometry. The implants were inserted into the femurs of 10 adult white rabbits. Animals were injected with fluorescent bone labels at 1, 5, and 7 weeks following surgery to monitor progress of bone formation. Animals were euthanized 8 weeks postsurgery, and block biopsies were prepared for histologic and histometric analysis.

Results: Microscopic evaluation showed the surfaces were quite irregular for both techniques; however, the test surface demonstrated consistently smaller surface irregularities. The differences in Sa values were significant (P = .022). No significant differences were found in the maximum peak-to-valley ratio values (P = .258). X-ray diffractometry analysis showed that titanium dioxide was found on the test surface. New bone was formed on both implant surfaces. The bone-implant contact pattern appeared to produce a broad-based direct contact. Test implants demonstrated 7.13% more bone to implant contact (P = .003) and 15.42% more bone to implant contact for 3 consecutive threads (P = .001) than control implants. Test implants demonstrated 37.04% more bone area 500 microm outside of implant threads (P = .004) and 51.97% more bone area within 3 consecutive threads (P = .001) than control implants. No significant differences were found in bone area within all implant threads between the two groups (P = .069).

Conclusion: This study demonstrated that implants heat-treated with H2O2/HCl solution enhanced peri-implant bone formation.
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June 2009
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