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1.  Dose-response relationship in cisplatin-treated breast cancer xenografts monitored with dynamic contrast-enhanced ultrasound 
BMC Cancer  2015;15:136.
Exactly assessing tumor response to different dose of chemotherapy would help to tailor therapy for individual patients. This study was to determine the feasibility of dynamic contrast-enhanced ultrasound (CEUS) in the evaluation of tumor vascular response to different dose cisplatin.
MCF-7 breast cancer bearing mice were treated with different dose of cisplatin in group B (1 mg/kg) and group C (3 mg/kg). A control group A was given with saline. Sequential CEUS was performed on days 0, 3 and 7 of the treatment, in which time-signal intensity curves were obtained from the intratumoral and depth-matched liver parenchyma. Peak enhancement (PE), area under the curve of wash-in (WiAUC), wash-in rate (WiR) and wash-in perfusion index (WiPI) were calculated from perfusion time-intensity curves and normalized with respect to the adjacent liver parenchyma. Histopathological analysis was conducted to evaluate tumor cell density and microvascular density (MVD).
Significant decreases in tumor normalized perfusion parameters were observed on day 3 in the high dose group and on day 7 in the low dose group. On day 7, nPE, nWiAUC, and nWiPI significantly decreased in group C and group B as compared with group A (P < 0.05), and further decreased in group C as compared with group B (P < 0.05). Significant decreases of tumor cell density and MVD were seen in treated group (group B and C) compared to control group (P < 0.05) and further decrease in group C compared to group B (P < 0.05).
Dynamic CEUS for quantification of tumor perfusion could be used to evaluate tumor vascular response to different dose of chemotherapy.
PMCID: PMC4381667  PMID: 25884471
Contrast-enhanced ultrasound; Perfusion; Cisplatin; Chemotherapy; Cancer
2.  Association between arterial stiffness and risk of coronary artery disease 
Pakistan Journal of Medical Sciences  2014;30(6):1314-1318.
Objective: To investigate the role of Brachial ankle Pulse Wave Relocity (baPWV) and cfPWV on the risk of Coronary artery disease and the interaction between baPWV and risk factors of Coronary artery disease (CAD).
Methods: A case-control study was conducted at Department of Emergency, SunYat-Sen memorial Hospital, China. We collected 332 cases with coronary artery disease and 328 subjects without CAD between February 2012 and October 2013. A multivariate logistic regression analysis was performed to analyze the risk factors of CAD.
Results: CAD subjects were more likely to be old age, and have higher BMI, waist-hip ratio, hypertension, fasting glucose, TG, carotid-femoral PWV (cfPWV) and baPWV, and CAD subjects had a lower TC, HDL–C and LDL-C. We found that older age, smoking, higher hypertension, TC, TG, HDL-C, LDL-C, carotid-femoral PWV (CfPWV) and baPWV were associated with risk of CAD. baPWV had significant interaction with age, TC, TG, HDL-C and LDL-C, carotid-femoral PWV (cfWV) was correlated with age, HDL-C and LDL-C.
Conclusion: This study showed that baPWV and cfPWV are two independent factors for the risk of Coronary artery disease, and baPWV and cfPWV have interaction with age, TC, TG, HDL-C and LDL-C.
PMCID: PMC4320722  PMID: 25674130
Arterial stiffness; baPWV; cfPWV; Coronary Artery Disease
3.  The Phylogeographical Pattern and Conservation of the Chinese Cobra (Naja atra) across Its Range Based on Mitochondrial Control Region Sequences 
PLoS ONE  2014;9(9):e106944.
The vulnerable Chinese cobra (Naja atra) ranges from southeastern China south of the Yangtze River to northern Vietnam and Laos. Large mountain ranges and water bodies may influence the pattern of genetic diversity of this species. We sequenced the mitochondrial DNA control region (1029 bp) using 285 individuals collected from 23 localities across the species' range and obtained 18 sequences unique to Taiwan from GenBank for phylogenetic and population analysis. Two distinct clades were identified, one including haplotypes from the two westernmost localities (Hekou and Miyi) and the other including haplotypes from all sampling sites except Miyi. A strong population structure was found (Φst = 0.76, P<0.0001) with high haplotype diversity (h = 1.00) and low nucleotide diversity (π = 0.0049). The Luoxiao and Nanling Mountains act as historical geographical barriers limiting gene exchange. In the haplotype network there were two “star” clusters. Haplotypes from populations east of the Luoxiao Mountains were represented within one cluster and haplotypes from populations west of the mountain range within the other, with haplotypes from populations south of the Nanling Mountains in between. Lineage sorting between mainland and island populations is incomplete. It remains unknown as to how much adaptive differentiation there is between population groups or within each group. We caution against long-distance transfers within any group, especially when environmental differences are apparent.
PMCID: PMC4153689  PMID: 25184236
4.  Protective Effect of Quercetin on the Development of Preimplantation Mouse Embryos against Hydrogen Peroxide-Induced Oxidative Injury 
PLoS ONE  2014;9(2):e89520.
Quercetin, a plant-derived flavonoid in Chinese herbs, fruits and wine, displays antioxidant properties in many pathological processes associated with oxidative stress. However, the effect of quercetin on the development of preimplantation embryos under oxidative stress is unclear. The present study sought to determine the protective effect and underlying mechanism of action of quercetin against hydrogen peroxide (H2O2)-induced oxidative injury in mouse zygotes. H2O2 treatment impaired the development of mouse zygotes in vitro, decreasing the rates of blastocyst formation and hatched, and increasing the fragmentation, apoptosis and retardation in blastocysts. Quercetin strongly protected zygotes from H2O2-induced oxidative injury by decreasing the reactive oxygen species level, maintaining mitochondrial function and modulating total antioxidant capability, the activity of the enzymatic antioxidants, including glutathione peroxidase and catalase activity to keep the cellular redox environment. Additionally, quercetin had no effect on the level of glutathione, the main non-enzymatic antioxidant in embryos.
PMCID: PMC3931787  PMID: 24586844
5.  Light trapping and surface plasmon enhanced high-performance NIR photodetector 
Scientific Reports  2014;4:3914.
Heterojunctions near infrared (NIR) photodetectors have attracted increasing research interests for their wide-ranging applications in many areas such as military surveillance, target detection, and light vision. A high-performance NIR light photodetector was fabricated by coating the methyl-group terminated Si nanowire array with plasmonic gold nanoparticles (AuNPs) decorated graphene film. Theoretical simulation based on finite element method (FEM) reveals that the AuNPs@graphene/CH3-SiNWs array device is capable of trapping the incident NIR light into the SiNWs array through SPP excitation and coupling in the AuNPs decorated graphene layer. What is more, the coupling and trapping of freely propagating plane waves from free space into the nanostructures, and surface passivation contribute to the high on-off ratio as well.
PMCID: PMC3904145  PMID: 24468857
6.  Ultrasonic spectrum analysis for in vivo characterization of tumor microstructural changes in the evaluation of tumor response to chemotherapy using diagnostic ultrasound 
BMC Cancer  2013;13:302.
There is a strong need for early assessment of tumor response to chemotherapy in order to avoid the adverse effects of unnecessary chemotherapy and to allow early transition to second-line therapy. The purpose of this study was to determine the feasibility of ultrasonic spectral analysis for the in vivo characterization of changes in tumor microstructure in the evaluation of tumor response to chemotherapy using diagnostic ultrasound.
Experiments were approved by the regional animal care committee. Twenty-four MCF-7 breast cancer bearing nude mice were treated with adriamycin or sterile saline administered by intraperitoneal injection. Ultrasonic radio-frequency (RF) data was collected using a clinically available ultrasound scanner (6-MHz linear transducer). Linear regression parameters (spectral slope and midband-fit) regarding the calibrated power spectra from the RF signals were tested to monitor tumor response to treatment. The section equivalent to the ultrasound imaging plane was stained with hematoxylin and eosin to allow for assessment of the density of tumor cell nuclei.
Treatment with adriamycin significantly reduced tumor growth in comparison with the control group (p = 0.003). Significant changes were observed in the ultrasonic parameters of the treated relative to the untreated tumors (p < 0.05). The spectral slope increased by 48.5%, from −10.66 ± 2.96 to −5.49 ± 2.69; the midband-fit increased by 12.8%, from −57.10 ± 7.68 to −49.81 ± 5.40. Treated tumors were associated with a significant decrease in the density of tumor cell nuclei as compared with control tumors (p < 0.001).
Ultrasonic spectral analysis can detect changes in tumor microstructure after chemotherapy, and this will be helpful in the early evaluation tumor response to chemotherapy.
PMCID: PMC3698196  PMID: 23800247
Adriamycin; Chemotherapy; Cancer; Ultrasonic spectrum analysis; Microstructure
7.  Treatment of gestational choriocarcinoma and massive ascites by hypothermic intraperitoneal perfusion chemotherapy guided by ultrasound followed by cytoreductive surgery 
A 33-year-old woman with very poor health status was admitted to our hospital because she had experienced increasing abdominal distention for three months, CT examination showed a right ovarian tumor together with massive abdominal and pelvic fluid. The patient was first treated by continuous circulatory hypothermic intraperitoneal perfusion chemotherapy (HIPC) guided by B-mode ultrasound, followed by cytoreductive surgery (CRS) after her ascites was controlled and her health condition improved. She was diagnosed with gestational choriocarcinoma (GC) based on the pathological examination of the hysterectomy specimen. She is still alive with very good health today. We think it may be a good choice for a patient in very poor health with GC accompanied by massive ascites to perform HIPC guided by B-mode ultrasound firstly, followed by CRS when the ascites has relieved and the patient’s health has improved.
PMCID: PMC3809254  PMID: 24353600
Gestational choriocarcinoma; Hypothermic; Intraperitoneal perfusion; Chemotherapy; Malignant ascites; Ultrasound
8.  Assessment of Early Tumor Response to Cytotoxic Chemotherapy with Dynamic Contrast-Enhanced Ultrasound in Human Breast Cancer Xenografts 
PLoS ONE  2013;8(3):e58274.
There is a strong need to assess early tumor response to chemotherapy in order to avoid adverse effects from unnecessary chemotherapy and allow early transition to second-line therapy. This study was to quantify tumor perfusion changes with dynamic contrast-enhanced ultrasound (CEUS) in the evaluation of early tumor response to cytotoxic chemotherapy. Sixty nude mice bearing with MCF-7 breast cancer were administrated with either adriamycin or sterile saline. CEUS was performed on days 0, 2, 4 and 6 of the treatment, in which time-signal intensity (SI) curves were obtained from the intratumoral and depth-matched liver parenchyma. Four perfusion parameters including peak enhancement (PE), area under the curve of wash-in (WiAUC), wash-in rate (WiR) and wash-in perfusion index (WiPI) were calculated from perfusion curves and normalized with respect to perfusion of adjacent liver parenchyma. Histopathological analysis was conducted to evaluate tumor perfusion, tumor cell density, microvascular density (MVD) and proliferating cell density. Significant decreases of tumor normalized perfusion parameters (i.e., nPE, nWiAUC, nWiR and nWiPI) were noticed between adriamycin-treated and control groups (P<0.01) 2 days after therapy. There were significant differences of tumor volumes between control and treated groups on day 6 (P<0.001) while there were no significant differences in tumor volume on days 0, 2 and 4 (P>0.05). Significant decreases of tumor perfusion, tumor cell density, MVD and proliferating cell density were seen in adrianycin-treated group 2 days after therapy when compared to control group (P<0.001). Dynamic CEUS for quantification of tumor perfusion could be used for early detection of cancer response to cytotoxic chemotherapy prior to notable tumor shrinkage.
PMCID: PMC3585723  PMID: 23469274
9.  Autophagy is differentially induced in prostate cancer LNCaP, DU145 and PC-3 cells via distinct splicing profiles of ATG5 
Autophagy  2013;9(1):20-32.
Autophagic responses to chemotherapeutic agents may vary greatly among different prostate cancer cells and have not been well characterized. In this study, we showed that valproic acid (VPA) induced conversion of LC3-I to LC3-II and formation of LC3 puncta, the typical markers of autophagy, in LNCaP and PC-3 cells. However, these markers were undetectable in DU145 cells upon autophagic stimulation, indicating a defect of autophagy in this cell line. Among several critical autophagy-related proteins, ATG5 and ATG12–ATG5 conjugates, which are essential for autophagy induction, were absent in DU145 cells. No canonical transcripts for full-length ATG5 but only two alternatively spliced ATG5 transcripts were identified in DU145 cells. These alternative transcripts lack one or two exons, leading to premature termination of ATG5 translation. Transfection of the wild-type ATG5 gene into DU145 cells rescued the production of ATG5 and ATG12–ATG5 conjugates, resulting in formation of LC3-II conjugates and LC3 puncta. Moreover, the levels of the SQSTM1 protein, which should be degradable as an autophagy adaptor, were much higher in DU145 than in LNCaP and PC-3 cells, but were significantly decreased after ATG5 restoration in DU145 cells. However, expression of wild-type ATG5 in DU145 or knockdown of ATG5 in LNCaP and PC-3 cells did not change the inhibitory effects of VPA on these cells. Collectively, these results indicated that VPA-induced autophagy in prostate cancer cells depended on ATG5 and more importantly, that the autophagy pathway was genetically impaired in DU145 cells, suggesting caution in interpreting autophagic responses in this cell line.
PMCID: PMC3542215  PMID: 23075929
valproic acid; autophagy; prostate cancer; ATG5; LC3; DU145 cells; LNCaP cells; PC-3 cells
10.  GP73 expression and its significance in the diagnosis of hepatocellular carcinoma: a review 
Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, and its incidence has been increasing worldwide. Serum alpha-fetoprotein (AFP) levels and abdominal ultrasound have been widely used for diagnosis as well as surveillance of HCC. However, the sensitivity and specificity of both AFP levels and ultrasound for HCC surveillance have some shortcomings, particularly in the early stages of the disease. Golgi protein-73 (GP73) is a type II Golgi-localized integral membrane protein that is normally expressed in epithelial cells of many human tissues. It is essential for human survival, and might have multiple roles for GP73 in epithelial cell function such as in the kidney and liver. However, details of its biochemical function and regulation of GP73 expression are unknown at present. GP73 expression is upregulated in serum samples from patients with liver disease, with expression being highest in HCC. Therefore, it may be useful as a new serum marker for detection of HCC in at high-risk population. But, this hypothesis needs to be proven in large cohorts.
PMCID: PMC3484483  PMID: 23119104
Hepatocellular carcinoma; liver disease; alpha-fetoprotein; golgi protein73; tumor marker
11.  Benefits of Iron supplementation for low birth weight infants: A systematic review 
BMC Pediatrics  2012;12:99.
A number of studies have reported on the effects of iron supplementation in low birth weight infants; however, no systematic review of the available evidence has been conducted to date. Hence, we performed a systematic review of the literature to examine the effects of iron supplementation on hematologic iron status, growth, neurodevelopment, and adverse effects in low birth weight/premature infants.
We searched the Cochrane Library, Medline, and PubMed for articles reporting on the effects of iron supplementation in low weight infants. The following search terms were used: “preterm born infant(s)/children”; “preterm infants”; “prematurely born children” “weight less than 1500 g at birth”; “born prematurely”; “low birth weight infant(s)”; “infants born preterm”; “prematurity”; “small-for-gestational age”; “very small gestational age infants”; “iron supplementation”; “iron intake”; “iron supplements”; “ferric and/or ferrous compounds”; and “ferrous sulphate/fumarate/sulfate”.
A total of 15 studies were identified and included in the systematic review. Supplemental iron was given orally or as an iron-fortified formula in 14/15 studies. The duration of treatment ranged from 1 week to 18 months. Iron supplementation significantly increased hematologic measures of iron status (including hemoglobin, hematocrit, serum ferritin) relative to placebo or over time in most studies. All controlled studies that examined iron-deficiency anemia (IDA)/ID reported a decreased prevalence of IDA/ID with iron supplementation. Dose dependent decreases in the prevalence of IDA/ID were reported in several studies. Of the 5 studies reporting on growth, none found any significant effect on growth-related parameters (length, height, weight, and head circumference). Only 2 studies reported on neurodevelopment; no marked effects were reported. There were no consistently reported adverse effects, including oxidative stress, inhibited nutrient absorption, morbidity, or the requirement for blood transfusion.
The available data suggest that iron supplementation increases the levels of hematologic indicators of iron status and reduces the prevalence of IDA/ID in low birth weight/premature infants. There is insufficient evidence to make a definitive statement regarding the effects of iron supplementation on growth, neurodevelopment, or the occurrence of adverse effects in low birth weight/premature infants.
PMCID: PMC3444344  PMID: 22794149
Anemia; Infant; Iron deficiency; Iron supplementation; Low birth weight
12.  Genetic Structure and Demographic History Should Inform Conservation: Chinese Cobras Currently Treated as Homogenous Show Population Divergence 
PLoS ONE  2012;7(4):e36334.
An understanding of population structure and genetic diversity is crucial for wildlife conservation and for determining the integrity of wildlife populations. The vulnerable Chinese cobra (Naja atra) has a distribution from the mouth of the Yangtze River down to northern Vietnam and Laos, within which several large mountain ranges and water bodies may influence population structure. We combined 12 microsatellite loci and 1117 bp of the mitochondrial cytochrome b gene to explore genetic structure and demographic history in this species, using 269 individuals from various localities in Mainland China and Vietnam. High levels of genetic variation were identified for both mtDNA and microsatellites. mtDNA data revealed two main (Vietnam + southern China + southwestern China; eastern + southeastern China) and one minor (comprising only two individuals from the westernmost site) clades. Microsatellite data divided the eastern + southeastern China clade further into two genetic clusters, which include individuals from the eastern and southeastern regions, respectively. The Luoxiao and Nanling Mountains may be important barriers affecting the diversification of lineages. In the haplotype network of cytchrome b, many haplotypes were represented within a “star” cluster and this and other tests suggest recent expansion. However, microsatellite analyses did not yield strong evidence for a recent bottleneck for any population or genetic cluster. The three main clusters identified here should be considered as independent management units for conservation purposes. The release of Chinese cobras into the wild should cease unless their origin can be determined, and this will avoid problems arising from unnatural homogenization.
PMCID: PMC3338645  PMID: 22558439
13.  GRK5 promotes F-actin bundling and targets bundles to membrane structures to control neuronal morphogenesis 
The Journal of Cell Biology  2011;194(6):905-920.
GRK5 couples actin cytoskeleton dynamics to membrane remodeling during neuronal morphogenesis independent of its kinase activity.
Neuronal morphogenesis requires extensive membrane remodeling and cytoskeleton dynamics. In this paper, we show that GRK5, a G protein–coupled receptor kinase, is critically involved in neurite outgrowth, dendrite branching, and spine morphogenesis through promotion of filopodial protrusion. Interestingly, GRK5 is not acting as a kinase but rather provides a key link between the plasma membrane and the actin cytoskeleton. GRK5 promoted filamentous actin (F-actin) bundling at the membranes of dynamic neuronal structures by interacting with both F-actin and phosphatidylinositol-4,5-bisphosphate. Moreover, separate domains of GRK5 mediated the coupling of actin cytoskeleton dynamics and membrane remodeling and were required for its effects on neuronal morphogenesis. Accordingly, GRK5 knockout mice exhibited immature spine morphology and deficient learning and memory. Our findings identify GRK5 as a critical mediator of dendritic development and suggest that coordinated actin cytoskeleton and membrane remodeling mediated by bifunctional actin-bundling and membrane-targeting molecules, such as GRK5, is crucial for proper neuronal morphogenesis and the establishment of functional neuronal circuitry.
PMCID: PMC3207290  PMID: 21930777
14.  Isolation and Characterization of Microsatellite Loci in the Chinese Cobra Naja atra (Elapidae) 
We characterize thirteen polymorphic microsatellite loci isolated from Naja atra genomic libraries, which were enriched for AC-motif microsatellites. The thirteen loci were screened on a group of 48 individuals from two populations, one in Yong’an and the other in Ganzhou. These markers revealed a relatively high degree of genetic diversity (4–12 alleles per locus) and heterozygosity (Ho ranged from 0.213–0.854 and He ranged from 0.301–0.838). Tests for departure from Hardy-Weinberg equilibrium and for linkage disequilibrium were conducted for each of the two populations separately. After sequential Bonferroni correction, none of the 13 loci showed significant departures from Hardy-Weinberg equilibrium. Hierarchical analysis of molecular variance indicated that a small but significant (P < 0.001) proportion (16.0%) of the total variation in the microsatellite DNA data were attributable to differences among populations, indicating geographical structuring and restricted gene flow. It could be attributable to the Wuyi mountains in the area having a sufficiently isolating effect to significantly reduce gene flow. Our microsatellite data also showed a low Nm (1.31) value in the two populations from mainland China. Thus, the Yong’an and Ganzhou populations could be treated as distinct evolutionarily significant units (ESUs). The high level of polymorphism revealed by these microsatellite markers will be useful for the study of gene flow, population structure and evolutionary history of N. atra.
PMCID: PMC3155360  PMID: 21845087
Naja atra; Elapidae; microsatellites; PCR primers; polymorphism
15.  EGF Transregulates Opioid Receptors through EGFR-mediated GRK2 Phosphorylation and Activation 
Molecular Biology of the Cell  2008;19(7):2973-2983.
G protein–coupled receptor (GPCR) kinases (GRKs) are key regulators of GPCR function. Here we demonstrate that activation of epidermal growth factor receptor (EGFR), a member of receptor tyrosine kinase family, stimulates GRK2 activity and transregulates the function of G protein–coupled opioid receptors. Our data showed that EGF treatment promoted DOR internalization induced by DOR agonist and this required the intactness of GRK2-phosphorylation sites in DOR. EGF stimulation induced the association of GRK2 with the activated EGFR and the translocation of GRK2 to the plasma membrane. After EGF treatment, GRK2 was phosphorylated at tyrosyl residues. Mutational analysis indicated that EGFR-mediated phosphorylation occurred at GRK2 N-terminal tyrosyl residues previously shown as c-Src phosphorylation sites. However, c-Src activity was not required for EGFR-mediated phosphorylation of GRK2. In vitro assays indicated that GRK2 was a direct interactor and a substrate of EGFR. EGF treatment remarkably elevated DOR phosphorylation in cells expressing the wild-type GRK2 in an EGFR tyrosine kinase activity–dependent manner, whereas EGF-stimulated DOR phosphorylation was greatly decreased in cells expressing mutant GRK2 lacking EGFR tyrosine kinase sites. We further showed that EGF also stimulated internalization of μ-opioid receptor, and this effect was inhibited by GRK2 siRNA. These data indicate that EGF transregulates opioid receptors through EGFR-mediated tyrosyl phosphorylation and activation of GRK2 and propose GRK2 as a mediator of cross-talk from RTK to GPCR signaling pathway.
PMCID: PMC2441682  PMID: 18463167

Results 1-15 (15)