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1.  Comprehensive Detection and Discrimination of Campylobacter Species by Use of Confocal Micro-Raman Spectroscopy and Multilocus Sequence Typing 
Journal of Clinical Microbiology  2012;50(9):2932-2946.
A novel strategy for the rapid detection and identification of traditional and emerging Campylobacter strains based upon Raman spectroscopy (532 nm) is presented here. A total of 200 reference strains and clinical isolates of 11 different Campylobacter species recovered from infected animals and humans from China and North America were used to establish a global Raman spectroscopy-based dendrogram model for Campylobacter identification to the species level and cross validated for its feasibility to predict Campylobacter-associated food-borne outbreaks. Bayesian probability coupled with Monte Carlo estimation was employed to validate the established Raman classification model on the basis of the selected principal components, mainly protein secondary structures, on the Campylobacter cell membrane. This Raman spectroscopy-based typing technique correlates well with multilocus sequence typing and has an average recognition rate of 97.21%. Discriminatory power for the Raman classification model had a Simpson index of diversity of 0.968. Intra- and interlaboratory reproducibility with different instrumentation yielded differentiation index values of 4.79 to 6.03 for wave numbers between 1,800 and 650 cm−1 and demonstrated the feasibility of using this spectroscopic method at different laboratories. Our Raman spectroscopy-based partial least-squares regression model could precisely discriminate and quantify the actual concentration of a specific Campylobacter strain in a bacterial mixture (regression coefficient, >0.98; residual prediction deviation, >7.88). A standard protocol for sample preparation, spectral collection, model validation, and data analyses was established for the Raman spectroscopic technique. Raman spectroscopy may have advantages over traditional genotyping methods for bacterial epidemiology, such as detection speed and accuracy of identification to the species level.
doi:10.1128/JCM.01144-12
PMCID: PMC3421791  PMID: 22740711
2.  Aurora-A Identifies Early Recurrence and Poor Prognosis and Promises a Potential Therapeutic Target in Triple Negative Breast Cancer 
PLoS ONE  2013;8(2):e56919.
Triple negative breast cancer (TNBC) acquires an unfavorable prognosis, emerging as a major challenge for the treatment of breast cancer. In the present study, 122 TNBC patients were subjected to analysis of Aurora-A (Aur-A) expression and survival prognosis. We found that Aur-A high expression was positively associated with initial clinical stage (P = 0.025), the proliferation marker Ki-67 (P = 0.001), and the recurrence rate of TNBC patients (P<0.001). In TNBC patients with Aur-A high expression, the risk of distant recurrence peaked at the first 3 years and declined rapidly thereafter, whereas patients with Aur-A low expression showed a relatively constant risk of recurrence during the entire follow-up period. Univariate and multivariate analysis showed that overexpression of Aur-A predicted poor overall survival (P = 0.002) and progression-free survival (P = 0.012) in TNBC. Furthermore, overexpression of Aur-A, associated with high Ki-67, predicted an inferior prognosis compared with low expression of both Aur-A and Ki-67. Importantly, we further found that Aur-A was overexpressed in TNBC cells, and inhibition of this kinase inhibited cell proliferation and prevented cell migration in TNBC. Our findings demonstrated that Aur-A was a potential therapeutic target for TNBC and inhibition of Aur-A kinase was a promising regimen for TNBC cancer therapy.
doi:10.1371/journal.pone.0056919
PMCID: PMC3577665  PMID: 23437271
3.  Draft Genome Sequence of Brucella abortus BCB027, a Strain Isolated from a Domestic Deer 
Genome Announcements  2013;1(1):e00130-12.
Many Brucella species are isolated from nonpreferred hosts, and these bacteria may show genetic differences from isolates from the preferred hosts. Here, we report the draft genome sequence of Brucella abortus BCB027, a novel strain isolated from a domestic deer.
doi:10.1128/genomeA.00130-12
PMCID: PMC3569276  PMID: 23405292
5.  Patterns and predictors of antihypertensive medication used 1 year after ischemic stroke or TIA in urban China 
Background
Antihypertensive treatment is recommended for secondary prevention in patients with ischemic stroke or transient ischemic attack. Prescription of and persistence with antihypertensives for secondary prevention is high in developed countries; whether this is true in China is unclear. The aim of this study was to describe the patterns of antihypertensive medication use, and factors associated with its use, 1 year after stroke in China.
Methods
A total of 7880 hypertensive patients diagnosed with ischemic stroke or transient ischemic attack in the China National Stroke Registry were analyzed. Multivariate logistic regression was used to identify factors associated with antihypertensive medication use at discharge and 12 months.
Results
Antihypertensive medication was used by 4458 (56.6%) participants at discharge and 2927 (37.1%) at 12 months. Calcium channel blockers were the most common among five classes of antihypertensive medication prescribed at discharge, and participants prescribed this class had the highest 1-year persistence. In-hospital health education was the strongest predictor of antihypertensive medication use at discharge; age and stroke severity were the strongest negative predictors of use at 12 months.
Conclusion
Use of antihypertensive medication 1 year after stroke is extremely low in China. Intervention is needed to improve adherence to antihypertensive medication, especially for the elderly and severe stroke patients.
doi:10.2147/PPA.S39800
PMCID: PMC3553336  PMID: 23378743
antihypertensive agents; secondary stroke prevention; stroke
6.  Exogenous plant MIR168a specifically targets mammalian LDLRAP1: evidence of cross-kingdom regulation by microRNA 
Cell Research  2011;22(1):107-126.
Our previous studies have demonstrated that stable microRNAs (miRNAs) in mammalian serum and plasma are actively secreted from tissues and cells and can serve as a novel class of biomarkers for diseases, and act as signaling molecules in intercellular communication. Here, we report the surprising finding that exogenous plant miRNAs are present in the sera and tissues of various animals and that these exogenous plant miRNAs are primarily acquired orally, through food intake. MIR168a is abundant in rice and is one of the most highly enriched exogenous plant miRNAs in the sera of Chinese subjects. Functional studies in vitro and in vivo demonstrated that MIR168a could bind to the human/mouse low-density lipoprotein receptor adapter protein 1 (LDLRAP1) mRNA, inhibit LDLRAP1 expression in liver, and consequently decrease LDL removal from mouse plasma. These findings demonstrate that exogenous plant miRNAs in food can regulate the expression of target genes in mammals.
doi:10.1038/cr.2011.158
PMCID: PMC3351925  PMID: 21931358
microRNA; MIR168a; LDLRAP1; low-density lipoprotein; microvesicle; cross-kingdom
8.  TOAST subtypes: its influence upon doctors’ decisions of antihypertensive prescription at discharge for ischemic stroke patients 
Aim
To investigate the influence of the Trial of Org 10172 in Acute Stroke Treatment (TOAST) subtypes in doctors’ decisions to use antihypertensive prescriptions at discharge for ischemic stroke patients in a real-world setting.
Methods
Using the China National Stroke Registry, we analyzed data from 12,063 hospitalized patients who had been diagnosed with ischemic stroke. The cause of ischemic stroke was classified according to the TOAST criteria. The information about the prescription of antihypertensive medication at discharge was extracted from medical records. Multivariate logistic regression was used to assess the impact of TOAST subtypes on the prescription of antihypertensive medication at discharge.
Results
Multivariate analysis showed that, compared with large artery atherosclerosis patients with moderate (<70%) stenosis, large artery atherosclerosis patients with severe (≥70%) stenosis or patients with stroke of undetermined etiology were less likely to be prescribed antihypertensive medication at discharge (odds ratio [OR], 0.72; 95% confidence interval [CI]: 0.59–0.88; OR, 0.71; 95% CI: 0.64–0.79), while patients with small artery occlusion were more likely to be prescribed antihypertensives (OR, 1.50; 95% CI: 1.33–1.69).
Conclusion
The TOAST subtype is an important determinant of the prescription of antihypertensive medication for ischemic stroke patients at discharge in normal clinical practice.
doi:10.2147/PPA.S38565
PMCID: PMC3529652  PMID: 23269862
antihypertensive agents; ischemic stroke; TOAST classification
9.  Hydrogen Sulfide as an Endogenous Modulator in Mitochondria and Mitochondria Dysfunction 
Hydrogen sulfide (H2S) has historically been considered to be a toxic gas, an environmental and occupational hazard. However, with the discovery of its presence and enzymatic production through precursors of L-cysteine and homocysteine in mammalian tissues, H2S has recently received much interest as a physiological signaling molecule. H2S is a gaseous messenger molecule that has been implicated in various physiological and pathological processes in mammals, including vascular relaxation, angiogenesis, and the function of ion channels, ischemia/reperfusion (I/R), and heart injury. H2S is an endogenous neuromodulator and present studies show that physiological concentrations of H2S enhance NMDA receptor-mediated responses and aid in the induction of hippocampal long-term potentiation. Moreover, in the field of neuronal protection, physiological concentrations of H2S in mitochondria have many favorable effects on cytoprotection.
doi:10.1155/2012/878052
PMCID: PMC3523162  PMID: 23304257
10.  Follicular Oocytes Better Support Development in Rabbit Cloning Than Oviductal Oocytes 
Cellular Reprogramming  2011;13(6):503-512.
Abstract
This study was conducted to determine the effect of rabbit oocytes collected from ovaries or oviducts on the developmental potential of nuclear transplant embryos. Donor nuclei were obtained from adult skin fibroblasts, cumulus cells, and embryonic blastomeres. Rabbit oocytes were flushed from the oviducts (oviductal oocytes) or aspirated from the ovaries (follicular oocytes) of superovulated does at 10, 11, or 12 h post-hCG injection. The majority of collected oocytes were still attached to the sites of ovulation on the ovaries. We found that follicular oocytes had a significantly higher rate of fusion with nuclear donor cells than oviductal oocytes. There was no difference in the cleavage rate between follicular and oviductal groups, but morula and blastocyst development was significantly higher in the follicular group than in the oviductal group. Two live clones were produced in follicular group using blastomere and cumulus nuclear donors, whereas one live clone was produced in the oviductal group using a cumulus nuclear donor. These results demonstrate that cloned rabbit embryos derived from follicular oocytes have better developmental competence than those derived from oviductal oocytes.
doi:10.1089/cell.2011.0030
PMCID: PMC3229818  PMID: 22029417
11.  Metabolism and Disposition of Tribendimidine and Its Metabolites in Healthy Chinese Volunteers 
Drugs in R&d  2012;10(2):83-90.
Background: Tribendimidine is a new anthelmintic agent synthesized by Chinese scientists. It is a broad spectrum agent with high activity against parasites. However, its disposition and metabolism remain unknown.
Objective: To investigate the metabolism, disposition, and metabolites of tribendimidine in healthy human volunteers.
Methods: Twelve healthy Chinese volunteers were chosen after clinical assessment of health status and laboratory tests. They received single oral doses of tribendimidine 400mg enteric-coated tablets. Blood and urine samples were collected at scheduled timepoints. Samples were qualitatively and quantitatively analyzed by liquid chromatography-mass spectrometric (LC-MS) and high performance liquid chromatography (HPLC) methods, respectively.
Results: Tribendimidine was rapidly and completely broken down to p-(1-dimethylamino ethylimino) aniline (dADT) and terephthalaldehyde (TPAL). Furthermore, dADT was partially transformed to acetylated dADT, and TPAL completely transformed to terephalic acid (TPAC). The main pharmacokinetic parameters (± SD) of dADT were as follows: elimination half life (t1/2) 4.74 ± 1.80 h; elimination rate constant (Ke) 0.16 ± 0.06 h−1; apparent volume of distribution (Vd/F) 12.23 ± 8.69L • kg−1; apparent total clearance of the drug from plasma (CL/F) 1.63 ± 0.58L • h−1 • kg−1; area under the plasma concentration-time curve (AUC) from time 0 to time 24 hours (AUC24) 4.29 ± 1.88 μg • mL−1 • h; AUC from time zero to infinity (AUC∞) 4.45 ± 1.81 μg • mL−1 • h; maximum plasma drug concentration (Cmax) 0.64 ± 0.27 μg • mL−1; and time to Cmax (tmax) 4.20 ± 0.71 h. A total of 35.28% dADT and 28.50% TPAC were excreted through the urine within 24 hours after tribendimidine administration.
Conclusion: These results reveal the disposition, metabolism, and main metabolites of tribendimidine in healthy Chinese volunteers.
doi:10.2165/11539320-000000000-00000
PMCID: PMC3585841  PMID: 20698716
12.  Green tea powder and Lactobacillus plantarum affect gut microbiota, lipid metabolism and inflammation in high-fat fed C57BL/6J mice 
Background
Type 2 diabetes is associated with obesity, ectopic lipid accumulation and low-grade inflammation. A dysfunctional gut microbiota has been suggested to participate in the pathogenesis of the disease. Green tea is rich in polyphenols and has previously been shown to exert beneficial metabolic effects. Lactobacillus plantarum has the ability to metabolize phenolic acids. The health promoting effect of whole green tea powder as a prebiotic compound has not been thoroughly investigated previously.
Methods
C57BL/6J mice were fed a high-fat diet with or without a supplement of 4% green tea powder (GT), and offered drinking water supplemented with Lactobacillus plantarum DSM 15313 (Lp) or the combination of both (Lp + GT) for 22 weeks. Parameters related to obesity, glucose tolerance, lipid metabolism, hepatic steatosis and inflammation were examined. Small intestinal tissue and caecal content were collected for bacterial analysis.
Results
Mice in the Lp + GT group had significantly more Lactobacillus and higher diversity of bacteria in the intestine compared to both mice in the control and the GT group. Green tea strongly reduced the body fat content and hepatic triacylglycerol and cholesterol accumulation. The reduction was negatively correlated to the amount of Akkermansia and/or the total amount of bacteria in the small intestine. Markers of inflammation were reduced in the Lp + GT group compared to control. PLS analysis of correlations between the microbiota and the metabolic variables of the individual mice showed that relatively few components of the microbiota had high impact on the correlation model.
Conclusions
Green tea powder in combination with a single strain of Lactobacillus plantarum was able to promote growth of Lactobacillus in the intestine and to attenuate high fat diet-induced inflammation. In addition, a component of the microbiota, Akkermansia, correlated negatively with several metabolic parameters known to be risk factors for the development of type 2 diabetes.
doi:10.1186/1743-7075-9-105
PMCID: PMC3538623  PMID: 23181558
Green tea; Lactobacillus plantarum; Type 2 diabetes; Obesity; Microbiota; Akkermansia; Inflammation; C57BL/6J
13.  Leidenfrost levitation: beyond droplets 
Scientific Reports  2012;2:797.
Friction is a major inhibitor in almost every mechanical system. Enlightened by the Leidenfrost effect – a droplet can be levitated by its own vapor layer on a sufficiently hot surface – we demonstrate for the first time that a small cart can also be levitated by Leidenfrost vapor. The levitated cart can carry certain amount of load and move frictionlessly over the hot surface. The maximum load that the cart can carry is experimentally tested over a range of surface temperatures. We show that the levitated cart can be propelled not only by gravitational force over a slanted flat surface, but also self-propelled over a ratchet shaped horizontal surface. In the end, we experimentally tested water consumption rate for sustaining the levitated cart, and compared the results to theoretical calculations. If perfected, this frictionless Leidenfrost cart could be used in numerous engineering applications where relative motion exists between surfaces.
doi:10.1038/srep00797
PMCID: PMC3495284  PMID: 23150770
14.  Structure-based discovery of highly selective phosphodiesterase-9A inhibitors and implications for inhibitor design 
Journal of medicinal chemistry  2012;55(19):8549-8558.
A new series of phosphodiesterase-9 (PDE9) inhibitors that contain a scaffold of 6-amino-pyrazolopyrimidinone have been discovered by a combination of structure-based design and computational docking. This procedure significantly saved load of chemical synthesis and is an effective method for the discovery of inhibitors. The best compound 28 has an IC50 of 21 nM and 3.3 µM respectively for PDE9 and PDE5, and about three orders of magnitude of selectivity against other PDE families. The crystal structure of the PDE9 catalytic domain in complex with 28 has been determined and shows a hydrogen bond between 28 and Tyr424. This hydrogen bond may account for the 860-fold selectivity of 28 against PDE1B, in comparison with about 30-fold selectivity of BAY73-6691. Thus, our studies suggest that Tyr424, a unique residue of PDE8 and PDE9, is a potential target for improvement of selectivity of PDE9 inhibitors.
doi:10.1021/jm301189c
PMCID: PMC3469756  PMID: 22985069
15.  Drug-induced liver injury in hospitalized patients with notably elevated alanine aminotransferase 
AIM: To identify the proportion, causes and the nature of drug-induced liver injury (DILI) in patients with notably elevated alanine aminotransferase (ALT).
METHODS: All the inpatients with ALT levels above 10 times upper limit of normal range (ULN) were retrospectively identified from a computerized clinical laboratory database at our hospital covering a 12-mo period. Relevant clinical information was obtained from medical records. Alternative causes of ALT elevations were examined for each patient, including biliary abnormality, viral hepatitis, hemodynamic injury, malignancy, DILI or undetermined and other causes. All suspected DILI cases were causality assessed using the Council for International Organizations of Medical Sciences scale, and only the cases classified as highly probable, probable, or possible were diagnosed as DILI. Comments related to the diagnosis of DILI in the medical record and in the discharge letter for each case were also examined to evaluate DILI detection by the treating doctors.
RESULTS: A total of 129 cases with ALT > 10 ULN were identified. Hemodynamic injury (n = 46, 35.7%), DILI (n = 25, 19.4%) and malignancy (n = 21, 16.3%) were the top three causes of liver injury. Peak ALT values were lower in DILI patients than in patients with hemodynamic injury (14.5 ± 5.6 ULN vs 32.5 ± 30.7 ULN, P = 0.001). Among DILI patients, one (4%) case was classified as definite, 19 (76%) cases were classified as probable and 5 (20%) as possible according to the CIOMS scale. A hepatocellular pattern was observed in 23 (92%) cases and mixed in 2 (8%). The extent of severity of liver injury was mild in 21 (84%) patients and moderate in 4 (16%). Before discharge, 10 (40%) patients were recovered and the other 15 (60%) were improved. The improved patients tended to have a higher peak ALT (808 ± 348 U/L vs 623 ± 118 U/L, P = 0.016) and shorter treatment duration before discharge (8 ± 6 d vs 28 ± 12 d, P = 0.008) compared with the recovered patients. Twenty-two drugs and 6 herbs were found associated with DILI. Antibacterials were the most common agents causing DILI in 8 (32%) cases, followed by glucocorticoids in 6 (24%) cases. Twenty-four (96%) cases received treatment of DILI with at least one adjunctive drug. Agents for treatment of DILI included anti-inflammatory drugs (e.g., glycyrrhizinate), antioxidants (e.g., glutathione, ademetionine 1,4-butanedisulfonate and tiopronin), polyene phosphatidyl choline and herbal extracts (e.g., protoporphyrin disodium and silymarin). Diagnosis of DILI was not mentioned in the discharge letter in 60% of the cases. Relative to prevalent cases and cases from wards of internal medicine, incident cases and cases from surgical wards had a higher risk of missed diagnosis in discharge letter [odds ratio (OR) 32.7, 95%CI (2.8-374.1), and OR 58.5, 95%CI (4.6-746.6), respectively].
CONCLUSION: DILI is mostly caused by use of antibacterials and glucocorticoids, and constitutes about one fifth of hospitalized patients with ALT > 10 ULN. DILI is underdiagnosed frequently.
doi:10.3748/wjg.v18.i41.5972
PMCID: PMC3491606  PMID: 23139615
Drug-induced liver injury; Abnormal liver enzyme; Alanine aminotransferase; Underdiagnosis; Adjunctive drugs
16.  Knockout of Insulin-Like Growth Factor-1 Receptor Impairs Distal Lung Morphogenesis 
PLoS ONE  2012;7(11):e48071.
Background
Insulin-like growth factors (IGF-I and -II) are pleiotropic regulators of somatic growth and development in vertebrate species. Endocrine and paracrine effects of both hormones are mediated by a common IGF type 1 receptor (IGF-1R). Lethal respiratory failure in neonatal IGF-1R knockout mice suggested a particular role for this receptor in pulmonary development, and we therefore investigated the consequences of IGF-1R inactivation in lung tissue.
Methods and Findings
We first generated compound heterozygous mutant mice harboring a hypomorphic (Igf1rneo) and a null (Igf1r−) allele. These IGF-1Rneo/− mice express only 22% of normal IGF-1R levels and are viable. In adult IGF-1Rneo/− mice, we assessed lung morphology and respiratory physiology and found normal histomorphometric characteristics and normal breathing response to hypercapnia. We then generated homozygous IGF-1R knockout mutants (IGF-1R−/−) and analyzed their lung development during late gestation using histomorphometric and immunohistochemical methods. IGF-1R−/− embryos displayed severe lung hypoplasia and markedly underdeveloped diaphragms, leading to lethal neonatal respiratory distress. Importantly, IGF-1R−/− lungs from late gestation embryos were four times smaller than control lungs and showed markedly thickened intersaccular mesenchyme, indicating strongly delayed lung maturation. Cell proliferation and apoptosis were significantly increased in IGF-1R−/− lung tissue as compared with IGF-1R+/+ controls. Immunohistochemistry using pro-SP-C, NKX2-1, CD31 and vWF as markers revealed a delay in cell differentiation and arrest in the canalicular stage of prenatal respiratory organ development in IGF-1R−/− mutant mice.
Conclusions/Significance
We found that low levels of IGF-1R were sufficient to ensure normal lung development in mice. In contrast, complete absence of IGF-1R significantly delayed end-gestational lung maturation. Results indicate that IGF-1R plays essential roles in cell proliferation and timing of cell differentiation during fetal lung development.
doi:10.1371/journal.pone.0048071
PMCID: PMC3491012  PMID: 23139760
17.  Resolvin D1 reverses chronic pancreatitis-induced mechanical allodynia, phosphorylation of NMDA receptors, and cytokines expression in the thoracic spinal dorsal horn 
BMC Gastroenterology  2012;12:148.
Background
We previously reported that immune activation in the spinal dorsal horn contributes to pain induced by chronic pancreatitis (CP). Targeting immune response in the CNS may provide effective treatments for CP-induced pain. Recent findings demonstrate that resolvin D1 (RvD1) can potently dampen inflammatory pain. We hypothesized that intrathecal injection of RvD1 may inhibit pain of CP.
Methods
Rat CP model was built through intrapancreatic infusion of trinitrobenzene sulfonic acid (TNBS). All the rats were divided into three groups: TNBS, sham, and naïve controls and were further divided for intrathecal RvD1 administration. Pain behavior of rats was tested with von Frey filaments. Anxiety-like behavior and free locomotor and exploration of rats were evaluated by open field test and elevated plus maze. Pancreatic histology was evaluated with hematoxylin and eosin staining. Phosphorylation of NMDA receptor and expression of inflammatory cytokines were examined with Western blot, real-time RT-PCR and ELISA.
Results
Behavioral study indicated that compared to the vehicle control, RvD1 (100 ng/kg) significantly decreased TNBS-induced mechanical allodynia at 2 h after administration (response frequencies: 49.2 ± 3.7% vs 71.3 ± 6.1%), and this effect was dose-dependent. Neither CP nor RvD1 treatment could affect anxiety-like behavior. CP or RvD1 treatment could not affect free locomotor and exploration of rats. Western blot analysis showed that compared with that of naïve group, phosphorylated NR1 (pNR1) and pNR2B in TNBS rats were significantly increased in the spinal cord (pNR1: 3.87±0.31 folds of naïve control, pNR2B: 4.17 ± 0.24 folds of naïve control). Compared to vehicle control, 10 ng/kg of RvD1 could significantly block expressions of pNR1 (2.21 ± 0.26 folds of naïve) and pNR2B (3.31 ± 0.34 folds of naïve). Real-time RT-PCR and ELISA data showed that RvD1 (10 ng/kg) but not vehicle could significantly block expressions of TNF-alpha, IL-1beta and IL-6. In addition, RvD1 did not influence pain behavior, NMDA receptor phosphorylation or cytokines production in sham-operated rats.
Conclusions
These data highly suggest that RvD1 could be a novel and effective treatment for CP-induced chronic pain.
doi:10.1186/1471-230X-12-148
PMCID: PMC3531273  PMID: 23092159
Chronic pancreatitis; Pain; Spinal dorsal horn; Resolvin D1; NMDA Receptor
18.  Quantum Tunneling of Magnetization in Ultrasmall Half-Metallic V3O4 Quantum Dots: Displaying Quantum Superparamagnetic State 
Scientific Reports  2012;2:755.
Quantum tunneling of magnetization (QTMs), stemming from their importance for understanding materials with unconventional properties, has continued to attract widespread theoretical and experimental attention. However, the observation of QTMs in the most promising candidates of molecular magnets and few iron-based compounds is limited to very low temperature. Herein, we first highlight a simple system, ultrasmall half-metallic V3O4 quantum dots, as a promising candidate for the investigation of QTMs at high temperature. The quantum superparamagnetic state (QSP) as a high temperature signature of QTMs is observed at 16 K, which is beyond absolute zero temperature and much higher than that of conventional iron-based compounds due to the stronger spin-orbital coupling of V3+ ions bringing high anisotropy energy. It is undoubtedly that this ultrasmall quantum dots, V3O4, offers not only a promising candidate for theoretical understanding of QTMs but also a very exciting possibility for computers using mesoscopic magnets.
doi:10.1038/srep00755
PMCID: PMC3477649  PMID: 23091695
19.  Free Cholesterol Induces Higher β-Sheet Content in Aβ Peptide Oligomers by Aromatic Interaction with Phe19 
PLoS ONE  2012;7(9):e46245.
Accumulating experimental evidence support an enhancing effect of free cholesterol on amyloid-beta (Aβ) aggregation. To probe the mechanisms of cholesterol-mediated Aβ aggregation, we applied all-atom molecular dynamic simulations on Aβ42 peptides in presence of free cholesterol. Several control systems were also designed to examine the specificity of cholesterol-residue interactions, including mutation on aromatic residue, substitution of cholesterol with sphingomyelin (SM) and DPPC bilayer, and a mixing SM and cholesterol. Each system was performed 4 independent simulations, with a total time of 560 ns. It was found that cholesterol increased β-sheet formation by 4 folds, but the Phe19→Ser mutation on Aβ42 peptide totally eliminated cholesterol’s effect. A stable contact was recognized between the steroid group of cholesterol and the Benzyl group of Phe19. Interestingly, our simulation revealed a regular 1 ns time interval between the establishment of cholesterol-phenylalanine contact and consequent β-sheet formation, suggesting an important role of steroid-benzyl interaction in cholesterol-mediated aggregation. The presence of SM slightly increased β-sheet formation, but the mixture of cholesterol and SM had a strong induction effect. Also, the measurement of Phe19-lipid distance indicates that aromatic side chains of peptides prone to bind to cholesterol on the surface of the mixed micelle. In the DPPC system, polar chains were attracted to the surface of membrane, yielding moderate increase of β-sheet formation. These results shed light on the mechanism of cholesterol-mediated fibrillogenesis, and help to differentiate the effects of cholesterol and other lipids on β-sheet formation process.
doi:10.1371/journal.pone.0046245
PMCID: PMC3458103  PMID: 23049991
20.  The clinical value of combined use of MR imaging and multi-slice spiral CT in limb salvage surgery for orthopaedic oncology patients: initial experience in nine patients 
Radiology and Oncology  2012;46(3):189-197.
Background
The purpose of this prospective study was to evaluate the value of the combined use of MR imaging and multi-slice spiral CT for limb salvage surgery in orthopaedic oncology patients.
Patients and methods
Nine consecutive patients with lower/upper limb malignant bone tumours (7 osteosarcomas and 2 chondrosarcomas) were treated with limb-salvaging procedures. Preoperative planning including determination of the osteotomy plane and diameters of the prosthesis was performed basing on the preoperative CT and MR images. The histopathology was performed as golden diagnostic criteria to evaluate the accuracy of CT and MR-based determination for tumour’s boundary.
Results
The tumour extension measured on MRI was consistent with the actual extension (P>0.05, paired Student’s t test), while the extension measured on CT imaging was less than the actual extension. The length, offset and alignment of the affected limb were reconstructed accurately after the operation. An excellent functional outcome was achieved in all patients.
Conclusions
In the present study, MRI was found to be superior to CT for determining the tumour extension, combined use of MRI and CT measurement provided high precision for the fit of the prosthesis and excellent functional results.
doi:10.2478/v10019-012-0020-4
PMCID: PMC3472943  PMID: 23077457
limb salvage surgery; magnetic resonance imaging (MRI); computed tomography (CT)
21.  Metastatic renal cell carcinoma presenting as gastric polyps: A case report and review of the literature 
INTRODUCTION
Renal cell carcinoma (RCC) accounts for approximately 3% of adult malignancies and is responsible for over 13,000 deaths in the U.S. annually. The fatalities are largely due to distant metastasis, with lung, liver, bone and brain being most commonly affected organs. Gastric metastasis from RCC is a rare event (less than 20 cases reported in the English language literature) and usually presents as a large, solitary mass or ulcer (average size of 4.8 cm) resembling primary gastric cancer. Here we report the first case of metastatic RCC presenting as small gastric polyps.
PRESENTATION OF CASE
The patient was a 60-year-old African American woman with a history of clear cell RCC (pT1bNX). She underwent esophagogastroduodenoscopy and colonoscopy 5 months after nephrectomy due to anemia. Two non-ulcerated, 0.6-cm benign-appearing polyps were found at the greater curvature of the gastric body, which were subsequently removed endoscopically. Unexpectedly, histopathologic examination of the gastric polyps revealed nested collections of vacuolated epithelioid cells in a background of delicate, arborizing vasculature, immediately beneath the congested and hyperplastic foveolar epithelium. A diagnosis of metastatic RCC was rendered after confirming the renal epithelial origin by immunohistochemical stains.
DISCUSSION
Gastric metastasis from RCC usually presents as a large, solitary mass or ulcer, but it can be subtle and present as multiple, small benign-appearing polyps.
CONCLUSION
A careful follow up and thorough endoscopic and histopathologic examinations should be conducted in patients with a history of RCC who present with gastrointestinal manifestations.
doi:10.1016/j.ijscr.2012.08.009
PMCID: PMC3484839  PMID: 22989776
Renal cell carcinoma; Metastasis; Gastric polyp
22.  Inhibition of osteoclastogenesis by RNA interference targeting RANK 
Background
Osteoclasts and osteoblasts regulate bone resorption and formation to allow bone remodeling and homeostasis. The balance between bone resorption and formation is disturbed by abnormal recruitment of osteoclasts. Osteoclast differentiation is dependent on the receptor activator of nuclear factor NF-kappa B (RANK) ligand (RANKL) as well as the macrophage colony-stimulating factor (M-CSF). The RANKL/RANK system and RANK signaling induce osteoclast formation mediated by various cytokines. The RANK/RANKL pathway has been primarily implicated in metabolic, degenerative and neoplastic bone disorders or osteolysis. The central role of RANK/RANKL interaction in osteoclastogenesis makes RANK an attractive target for potential therapies in treatment of osteolysis. The purpose of this study was to assess the effect of inhibition of RANK expression in mouse bone marrow macrophages on osteoclast differentiation and bone resorption.
Methods
Three pairs of short hairpin RNAs (shRNA) targeting RANK were designed and synthesized. The optimal shRNA was selected among three pairs of shRNAs by RANK expression analyzed by Western blot and Real-time PCR. We investigated suppression of osteoclastogenesis of mouse bone marrow macrophages (BMMs) using the optimal shRNA by targeting RANK.
Results
Among the three shRANKs examined, shRANK-3 significantly suppressed [88.3%] the RANK expression (p < 0.01). shRANK-3 also brought about a marked inhibition of osteoclast formation and bone resorption as demonstrated by tartrate–resistant acid phosphatase (TRAP) staining and osteoclast resorption assay. The results of our study show that retrovirus-mediated shRANK-3 suppresses osteoclast differentiation and osteolysis of BMMs.
Conclusions
These findings suggest that retrovirus-mediated shRNA targeting RANK inhibits osteoclast differentiation and osteolysis. It may appear an attractive target for preventing osteolysis in humans with a potential clinical application.
doi:10.1186/1471-2474-13-154
PMCID: PMC3475138  PMID: 22913338
RANK; Inhibition; RNA interference; Cell culture
23.  Short term effects of different omega-3 fatty acid formulation on lipid metabolism in mice fed high or low fat diet 
Background
Bioactivities of Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) depend on their chemical forms. The present study was to investigate short term effects of triglyceride (TG), ethyl ester (EE), free fatty acid (FFA) and phospholipid (PL) forms of omega-3 fatty acid (FA) on lipid metabolism in mice, fed high fat or low fat diet.
Method
Male Balb/c mice were fed with 0.7% different Omega-3 fatty acid formulation: DHA bound free fatty acid (DHA-FFA), DHA bound triglyceride (DHA-TG), DHA bound ethyl ester (DHA-EE) and DHA bound phospholipid (DHA-PL) for 1 week, with dietary fat levels at 5% and 22.5%. Serum and hepatic lipid concentrations were analyzed, as well as the fatty acid composition of liver and brain.
Result
At low fat level, serum total cholesterol (TC) level in mice fed diets with DHA-FFA, DHA-EE and DHA-PL were significantly lower than that in the control group (P < 0.05). Hepatic TG level decreased significantly in mice fed diets with DHA-TG (P < 0.05), DHA-EE (P < 0.05) and DHA-PL (P < 0.05), while TC level in liver was significantly lower in mice fed diets with TG and EE compared with the control group (P < 0.05). At high fat level, mice fed diets with DHA-EE and DHA-PL had significantly lower hepatic TC level compared with the control diet (P < 0.05). Hepatic PL concentration experienced a significant increase in mice fed the diet with PL at high fat level (P < 0.05). Furthermore, both at low and high fat levels, hepatic DHA level significantly increased and AA level significantly decreased in all forms of DHA groups (P < 0.05), compared to control groups at two different fat levels, respectively. Additionally, cerebral DHA level in mice fed diets with DHA-FFA, DHA-EE and DHA-PL significantly increased compared with the control at high fat level (P < 0.05), but no significant differences were observed among dietary treatments for mice fed diets with low fat level.
Conclusion
The present study suggested that not only total dietary fat content but also the molecular forms of omega-3 fatty acids contributed to lipid metabolism in mice. DHA-PL showed effective bioactivity in decreasing hepatic and serum TC, TG levels and increasing omega-3 concentration in liver and brain.
doi:10.1186/1476-511X-11-70
PMCID: PMC3393618  PMID: 22676394
Omega-3 fatty acid; DHA; EPA; Lipid metabolism; Triglycerides; Ethyl ester; Phospholipids
24.  Dietary sea cucumber cerebroside alleviates orotic acid-induced excess hepatic adipopexis in rats 
Background
Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease in industrialized countries. The present study was undertaken to explore the preventive effect of dietary sea cucumber cerebroside (SCC) extracted from Acaudina molpadioides in fatty liver rats.
Methods
Male Wistar rats were randomly divided into four groups including normal control group, NAFLD model group, and two SCC-treated groups with SCC at 0.006% and 0.03% respectively. The fatty liver model was established by administration of 1% orotic acid (OA) to the rats. After 10d, serum and hepatic lipid levels were detected. And the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were also determined. Besides, to gain the potential mechanism, the changes of key enzymes and gene expressions related to the hepatic lipid metabolism were measured.
Results
Dietary SCC at the level of 0.006% and 0.03% ameliorated the hepatic lipid accumulation in fatty liver rats. SCC administration elevated the serum triglyceride (TG) level and the ALT, AST activities in OA-fed rats. The activities of hepatic lipogenic enzymes including fatty acid synthase (FAS), malic enzyme (ME) and glucose-6-phosphatedehydrogenase (G6PDH) were inhibited by SCC treatment. And the gene expressions of FAS, ME, G6PDH and sterol-regulatory element binding protein (SREBP-1c) were also reduced in rats fed SCC. However, dietary SCC didn't affect the activity and mRNA expression of carnitine palmitoyltransferase (CPT) in liver. Besides, suppression of microsomal triglyceride transfer protein (MTP) activity was observed in SCC-feeding rats.
Conclusions
These results suggested that dietary SCC could attenuate hepatic steatosis due to its inhibition of hepatic lipogenic gene expression and enzyme activity and the enhancement of TG secretion from liver.
doi:10.1186/1476-511X-11-48
PMCID: PMC3477080  PMID: 22569330
Sea cucumber cerebroside; Orotic acid; Fatty liver; Lipogenesis; Microsomal triglyceride transfer protein
25.  Molecular Prognostic Prediction for Locally Advanced Nasopharyngeal Carcinoma by Support Vector Machine Integrated Approach 
PLoS ONE  2012;7(3):e31989.
Background
Accurate prognostication of locally advanced nasopharyngeal carcinoma (NPC) will benefit patients for tailored therapy. Here, we addressed this issue by developing a mathematical algorithm based on support vector machine (SVM) through integrating the expression levels of multi-biomarkers.
Methodology/Principal Findings
Ninety-seven locally advanced NPC patients in a randomized controlled trial (RCT), consisting of 48 cases serving as training set and 49 cases as testing set of SVM models, with 5-year follow-up were studied. We designed SVM models by selecting the variables from 38 tissue molecular biomarkers, which represent 6 tumorigenesis signaling pathways, and 3 EBV-related serological biomarkers. We designed 3 SVM models to refine prognosis of NPC with 5-year follow-up. The SVM1 displayed highly predictive sensitivity (sensitivity, specificity were 88.0% and 81.9%, respectively) by integrating the expression of 7 molecular biomarkers. The SVM2 model showed highly predictive specificity (sensitivity, specificity were 84.0% and 94.5%, respectively) by grouping the expression level of 12 molecular biomarkers and 3 EBV-related serological biomarkers. The SVM3 model, constructed by combination SVM1 with SVM2, displayed a high predictive capacity (sensitivity, specificity were 88.0% and 90.3%, respectively). We found that 3 SVM models had strong power in classification of prognosis. Moreover, Cox multivariate regression analysis confirmed these 3 SVM models were all the significant independent prognostic model for overall survival in testing set and overall patients.
Conclusions/Significance
Our SVM prognostic models designed in the RCT displayed strong power in refining patient prognosis for locally advanced NPC, potentially directing future target therapy against the related signaling pathways.
doi:10.1371/journal.pone.0031989
PMCID: PMC3302890  PMID: 22427815

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