Influence of Shrinkage and Viscosity of Flowable Composite Liners on Cervical Microleakage of Class II Restorations: A Micro-CT Analysis

This study determined the influence of shrinkage and viscosity of flowable composite liners on the cervical microleakage of Class II restorations using micro-CT. Seven composites of varying viscosities were selected and included five giomers (Shofu Beautifil II [BF], Flow Plus F00 and F03 [F00 and F03], Flow F02 and F10 [F02 and F10]) and 2 nano-filled composites (3M-ESPE Filtek Z350 [Z350] and Filtek Z350 Flowable [Z350F]). Polymerization shrinkage (n=7) was assessed with the Acuvol volumetric shrinkage analyzer while complex viscosity was determined with the advanced rheometric expansion system at 25°C. Standardized Class II restorations incorporating 1-mm horizontal layers of different flowable liners and 3-mm oblique layers of BF or Z350 were subjected to a silver nitrate test for 24 hours and examined using micro-CT. Microleakage was determined at 0.1-mm intervals from the buccal to lingual surfaces providing 30 sites per specimen and scored accordingly. Statistical analysis was performed with the one-way ANOVA, Kruskal-Wallis test, and Spearman's rho correlation at a significance level of p<0.05. Mean volumetric shrinkage ranged from 5.33±0.17% to 2.35±0.02% for F02 to Z350, respectively. The flowable materials had significantly higher shrinkage than did their sculptable counterparts (BF and Z350). Complex viscosities ranged from 9.65 to 4.20 (Z350 and F10, respectively) at a frequency of 10 rad/s and from 8.16 to 3.28 (Z350 and F03, respectively) for 100 rad/s. Giomer restorations had significantly less leakage than did those restored with nano-filled composites. No microleakage was observed with restorations lined with F02 or F10. The use of flowable liners reduced cervical microleakage of Class II restorations. Interfacial integrity of Class II restorations was significantly correlated with liner viscosity, filler volume, and shrinkage.

New insights into the plasmonic enhancement for photocatalytic H2 production by Cu–TiO2 upon visible light illumination

Cu nanoparticles were deposited on the surface of commercial TiO₂ nanoparticles (Cu–TiO₂) using different methods aiming at the production of highly efficient visible light photocatalysts.

Expression of C-myc and β-catenin and their correlation in triple negative breast cancer

BACKGROUND

The present study was planned to study the expression of C-myc and β-catenin in triple negative breast cancer (TNBC) tissue. Furthermore, their relations to clinical features of the tumor and the survival prognosis were also studied. Additionally, correlation was evaluated between the expression of C-myc and β-catenin to provide the theoretical basis for the targeted therapy of TNBC.

METHODS

Sixty cases of patients diagnosed with TNBC for the first time were selected for the study. The immumo-histochemical staining was employed to detect the positive expression rates of C-myc and β-catenin in cancer tissues and normal mammary tissues 3 cm away from the carcinoma. Fluorescence in situ hybridization (FISH) was used to test the gene amplification of C-myc in order to analyze the relation between C-myc and the protein expression of β-catenin. Further, kept the median follow-up time to 25.0 months in order to compare the survival prognosis.

RESULTS

The positive expression rates of C-myc and β-catenin in cancer tissues were significantly higher than those in precancerous normal tissues (P<0.05). Furthermore, the expression rates were related with the diameter of tumor, clinical staging, pathological grading and lymphatic metastasis (P<0.5). There were 33 cases that exhibited an increase in C-myc gene copy number and the gene amplification was observed to be 55% in total. On the other hand, patients with positive expression of C-myc and β-catenin protein exhibited a shortened disease-free survival without tumor with an increasing recurrence rate and lower survival rate (P<0.05).

CONCLUSIONS

The present study concludes that the positive expression of C-myc and β-catenin in TNBC tissue might be closely correlated with clinical features of cancer and the survival prognosis.

Vitamin D Status and Prevalent Early Age-Related Macular Degeneration in African Americans and Caucasians: The Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVES

Vitamin D status has been hypothesized to protect against development of early age-related macular degeneration (AMD) via its anti-inflammatory properties and its possible beneficial influence on blood pressure control. We investigated the association between vitamin D status and prevalent early AMD in a community-based cohort.

DESIGN

This was a cross-sectional study.

SETTING

This was a secondary data analysis of already existing data from the Atherosclerosis Risk in Communities Study (ARIC) cohort collected from 1990 to 1995.

PARTICIPANTS

There were 9,734 (7,779 Caucasians, 1,955 African American) ARIC participants (aged 46 to 70 at visit 2 [1990-1992]) with 25(OH)D data available at visit 2, AMD assessment at visit 3 (1993-1995), and complete covariate data.

MEASUREMENTS

Vitamin D status was assessed with serum 25-hydroxyvitamin D (25(OH)D) concentrations from bloods drawn at visit 2. Prevalent, early AMD (n=511) was assessed at visit 3 (1993-95) with nonmydriatic retinal photographs of one randomly chosen eye. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for early AMD by categories of 25(OH)D in nmol/L (deficient <30, inadequate 30-<50, and two categories of adequate status: 50-<75 and ≥75). Linear trend was estimated using continuous 25(OH)D concentrations. ORs were adjusted for age, race, and smoking status. We further adjusted for hypertension status to examine if vitamin D status influenced early AMD via its effects on blood pressure. Exploratory analyses of effect modification by age, sex, race and high risk genotypes [Y402H complement factor H (CFH) rs1061170 and the A69S age-related maculopathy susceptibility 2 (ARMS2) rs10490924 polymorphisms] were conducted.

RESULTS

The prevalence of early AMD was 5%, and 5% of participants were vitamin D deficient. The adjusted OR (95% CIs) for early AMD among those with adequate (≥75 nmol/L) compared to deficient (<30 nmol/L) vitamin D status was 0.94 (0.59-1.50), p-trend=0.86. Further adjustment for hypertension status did not influence results (OR [95% CI]=0.95 [0.59-1.52], p-trend=0.84). Results did not vary significantly by age, race, sex, early AMD subtype (soft drusen or retinal pigment epithelium depigmentation), or ARMS2 genotype. Results did not vary significantly by CFH genotype in African Americans. The p for multiplicative interaction between 25(OH)D and CFH genotype was 0.06 in Caucasians, but OR [95% CIs] for AMD by vitamin D status were similar in each CFH genotype and not statistically significant.

CONCLUSIONS

Vitamin D status was not associated with early AMD in this cohort sample.

[The characteristics of a mouse model with nasal polyp established by lipopolysaccharide]

Objective:To explore the effect of lipopolysaccharide(LPS) on the formation of nasal polyps in mice and its mechanism.Method:Five or ten μg of LPS were dropped into the nasal cavities of six to eight-week C57BL/6J mice in order to establish animal models with nasal polyps.Buried food pellets experiment was used to assess olfactory function of mice.Hematoxylin-eosin staining,olfactory marker protein(OMP),and myeloperoxidase(MPO) for neutrophil immunohistochemistry were used to observe histopathological changes in the nasal mucosa.The expression levels of cytokines,such as interferon(IFN)-γ,tumor necrosis factor(TNF)-α,IL-6 in the nasal lavage fluid,were detected by ELISA.Result:Compared to the control group,mice in the LPS groups showed significant nasal polyp formation,olfactory dysfunction,more MPO⁺ cells while less OMP⁺ cells in the nasal mucosa,as well as increased significantly levels of IFN-γ,TNF-α,and IL-6 in the nasal lavage fluids(all P<0.05).Conclusion:LPS from Gram negative bacteria alone can induce the formation of nasal polyps in mice,characterized by more neutrophils,olfactory dysfunction,and increasing Th1 cytokine.Therefore,this model is commensurate with the characteristics of primary nasal polyps found in China and other major Asian.The current study suggests that LPS may be one of the important pathogenesis of gram negative bacteria in the nasal polyps.

[Micro-CT observations of the adaptation at gingival wall in Class II restorations with different dental restorative materials]

OBJECTIVE

To evaluate the adaptation of different materials for gingival layer in Class II restorations using Micro-CT.

METHODS

Eighteen extracted human premolars were selected, and Class II cavities were prepared. The teeth were randomly divided into six groups and restored using layering technique. Six materials were used for gingival layer, including four injectable materials: Beautifil Flow Plus F00 (F00), Beautifil Flow F10 (F10), Filtek Z350 Flowable (Z350F), FujiII LC CAPSULE (Fuji), and two packable materials: BeautifilII (BF), Filtek Z350 (Z350). The restored teeth were scanned with micro-CT and the images were 3D reconstructed to evaluate the volumes and the distribution of the voids on the restoration-tooth interface of the gingival layer. The volume of the voids were statistically analyzed using nonparametric Jonckheere-Terpstra tests.

RESULTS

The volumes (mm(3)) of the voids on the restoration-tooth interface were: Z350F (0.000 15), F10 (0.000 39), F00 (0.012), Fuji (0.070), Z350 (0.16) and BF (0.20). There were significant differences between Z350F/F10 and Fuji/Z350/BF (P < 0.05). Most of the voids were found on the point-line angles of the cavities.

CONCLUSION

The voids on the restoration-tooth interface were mainly on the point-line angles of the cavities. Injectable materials with high flowablility could reduce the restoration-tooth interface voids significantly when used for the gingival layer in Class II restorations.

Ankyrin repeats of ANKRA2 recognize a PxLPxL motif on the 3M syndrome protein CCDC8

Peptide motifs are often used for protein-protein interactions. We have recently demonstrated that ankyrin repeats of ANKRA2 and the paralogous bare lymphocyte syndrome transcription factor RFXANK recognize PxLPxL/I motifs shared by megalin, three histone deacetylases, and RFX5. We show here that that CCDC8 is a major partner of ANKRA2 but not RFXANK in cells. The CCDC8 gene is mutated in 3M syndrome, a short-stature disorder with additional facial and skeletal abnormalities. Two other genes mutated in this syndrome encode CUL7 and OBSL1. While CUL7 is a ubiquitin ligase and OBSL1 associates with the cytoskeleton, little is known about CCDC8. Binding and structural analyses reveal that the ankyrin repeats of ANKRA2 recognize a PxLPxL motif at the C-terminal region of CCDC8. The N-terminal part interacts with OBSL1 to form a CUL7 ligase complex. These results link ANKRA2 unexpectedly to 3M syndrome and suggest novel regulatory mechanisms for histone deacetylases and RFX7.

Impact of exercise intensity on cardiac function in adolescent runners

BACKGROUND

Prolonged exercise may induce a transient reduction in the left ventricular (LV) function (exercise-induced cardiac fatigue) in adults. However, data related to the cardiovascular consequences of prolonged exercise in adolescents are extremely limited. This study examined the impact of exercise intensity adopted in routine long-distance run training on LV function in trained adolescent runners in a laboratory-based setting.

METHODS

Twelve male adolescent runners (14.5 ± 1.5 years) performed two 90-min treadmill runs with intensity set at the running speeds that corresponded to either 80% (T1) or 100% (T2) ventilatory threshold. LV function was examined echocardiographically pre- and post-exercise.

RESULTS

The two-factor repeated-measures ANOVA revealed no significant (P>0.05) main effects for the intensity and the interaction of intensityÍ pre- and postexercise in ejection fraction (EF), systolic blood pressure/end systolic volume ratio (SBP/ESV) and early to atrial diastolic flow velocity ratio (E:A). Nevertheless, the main effect for time course in EF was significant (P<0.05). Pre-exercise EF in T1 (74 ± 5 vs. 70 ± 5%, P<0.05), but not in T2 (75 ± 4 vs. 72 ± 7%, P>0.05), decreased significantly post-exercise, yet this did not reach clinical levels. Further, no difference (P>0.05) was found between pre- and post-exercise in SBP/ESV (T1: 3.9 ± 0.9 vs. 3.7 ± 1.1; T2: 4.0 ± 0.7 vs. 4.6 ± 1.9 mmHg·ml⁻¹) and E:A (T1: 1.87 ± 0.11 vs. 1.87 ± 0.11; T2: 1.83 ± 0.11 vs. 1.87 ± 0.09) in both trials.

CONCLUSION

These findings suggest that the training intensities adopted in routine long-distance run training in the adolescent runners do not seem to induce cardiac fatigue. Adolescent hearts appear to cope well with prolonged run performed on training.

Rapid reuptake of granzyme B leads to emperitosis: an apoptotic cell-in-cell death of immune killer cells inside tumor cells

A cell-in-cell process refers to the invasion of one living cell into another homotypic or heterotypic cell. Different from non-apoptotic death processes of internalized cells termed entosis or cannibalism, we previously reported an apoptotic cell-in-cell death occurring during heterotypic cell-in-cell formation. In this study, we further demonstrated that the apoptotic cell-in-cell death occurred only in internalized immune killer cells expressing granzyme B (GzmB). Vacuole wrapping around the internalized cells inside the target cells was the common hallmark during the early stage of all cell-in-cell processes, which resulted in the accumulation of reactive oxygen species and subsequent mitochondrial injury of encapsulated killer or non-cytotoxic immune cells. However, internalized killer cells mediated rapid bubbling of the vacuoles with the subsequent degranulation of GzmB inside the vacuole of the target cells and underwent the reuptake of GzmB by killer cells themselves. The confinement of GzmB inside the vacuole surpassed the lysosome-mediated cell death occurring in heterotypic or homotypic entosis processes, resulting in a GzmB-triggered caspase-dependent apoptotic cell-in-cell death of internalized killer cells. On the contrary, internalized killer cells from GzmB-deficient mice underwent a typical non-apoptotic entotic cell-in-cell death similar to that of non-cytotoxic immune cells or tumor cells. Our results thus demonstrated the critical involvement of immune cells with cytotoxic property in apoptotic cell-in-cell death, which we termed as emperitosis taken from emperipolesis and apoptosis. Whereas entosis or cannibalism may serve as a feed-on mechanism to exacerbate and nourish tumor cells, emperitosis of immune killer cells inside tumor cells may serve as an in-cell danger sensation model to prevent the killing of target cells from inside, implying a unique mechanism for tumor cells to escape from immune surveillance.

The tumor suppressor kinase LKB1 activates the downstream kinases SIK2 and SIK3 to stimulate nuclear export of class IIa histone deacetylases

Histone deacetylases 4 (HDAC4), -5, -7, and -9 form class IIa within the HDAC superfamily and regulate diverse physiological and pathological cellular programs. With conserved motifs for phosphorylation-dependent 14-3-3 binding, these deacetylases serve as novel signal transducers that are able to modulate histone acetylation and gene expression in response to extracellular cues. Here, we report that in a PKA-sensitive manner the tumor suppressor kinase LKB1 acts through salt-inducible kinase 2 (SIK2) and SIK3 to promote nucleocytoplasmic trafficking of class IIa HDACs. Both SIK2 and SIK3 phosphorylate the deacetylases at the conserved motifs and stimulate 14-3-3 binding. SIK2 activates MEF2-dependent transcription and relieves repression of myogenesis by the deacetylases. Distinct from SIK2, SIK3 induces nuclear export of the deacetylases independent of kinase activity and 14-3-3 binding. These findings highlight the difference among members of the SIK family and indicate that LKB1-dependent SIK activation constitutes an important signaling module upstream from class IIa deacetylases for regulating cellular programs controlled by MEF2 and other transcription factors.

Microenvironment-dependent homeostasis and differentiation of epidermal basal undifferentiated keratinocytes and their clinical applications in skin repair

Skin homeostasis is maintained by controlling the balance between proliferation and differentiation of epidermal stem cells. The microenvironment, including extrinsic stresses, growth factors, soluble molecules, cell-ECM and cell-cell communications, plays an important role in cell fate determination in vivo and in vitro. In response to external signals, keratinocytes cooperate with other cell types to modulate and facilitate the wound microenvironment during wound healing; however, the aberrant signals or conjunctions in the environment will lead to pathologic abnormalities. In addition, despite some drawbacks, the epidermal stem-cellbased bioengineered skin substitutes have greatly improved the quality of cutaneous repair. Thus, exploring the characteristics and regulation mechanisms of microenvironment-dependent homeostasis and differentiation of epidermal basal undifferentiated keratinocytes is necessary to understand skin development and wound repair and to design novel therapeutic strategies for skin wound healing.

Sequence-specific recognition of a PxLPxI/L motif by an ankyrin repeat tumbler lock

Ankyrin repeat family A protein 2 (ANKRA2) interacts with the plasma membrane receptor megalin and the class IIa histone deacetylases HDAC4 and HDAC5. We report that the ankyrin repeat domains of ANKRA2 and its close paralog regulatory factor X-associated ankyrin-containing protein (RFXANK) recognize a PxLPxI/L motif found in diverse binding proteins, including HDAC4, HDAC5, HDAC9, megalin, and regulatory factor X, 5 (RFX5). Crystal structures of the ankyrin repeat domain of ANKRA2 in complex with its binding peptides revealed that each of the middle three ankyrin repeats of ANKRA2 recognizes a residue from the PxLPxI/L motif in a tumbler-lock binding mode, with ANKRA2 acting as the lock and the linear binding motif serving as the key. Structural analysis showed that three disease-causing mutations in RFXANK affect residues that are critical for binding to RFX5. These results suggest a fundamental principle of longitudinal recognition of linear sequences by a repeat-type domain. In addition, phosphorylation of serine 350, a residue embedded within the PxLPxI/L motif of HDAC4, impaired the binding of ANKRA2 but generated a high-affinity docking site for 14-3-3 proteins, which may help sequester this HDAC in the cytoplasm. Thus, the binding preference of the PxLPxI/L motif is signal-dependent. Furthermore, proteome-wide screening suggested that a similar phosphorylation-dependent switch may operate in other pathways. Together, our findings uncover a previously uncharacterized sequence- and signal-dependent peptide recognition mode for a repeat-type protein domain.

Single nucleotide polymorphisms in uracil-processing genes, intake of one-carbon nutrients and breast cancer risk

BACKGROUND/OBJECTIVES

The misincorporation of uracil into DNA leads to genomic instability. In a previous study, some of us identified four common single nucleotide polymorphisms (SNPs) in uracil-processing genes (rs2029166 and rs7296239 in SMUG1, rs34259 in UNG and rs4775748 in DUT) that were associated with significantly altered levels of uracil in human DNA. We investigated whether any of these SNPs are associated with an altered risk of developing breast cancer and if one-carbon nutrients intake can modify their effects.

SUBJECTS/METHODS

We genotyped the four SNPs in 1077 cases of incident breast cancer and 1910 age and race-matched controls in the Western New York Exposures and Breast Cancer (WEB) Study and examined associations with breast cancer risk and interactions with intake of folate, vitamins B6 and B12.

RESULTS

After adjustment for known risk factors for breast cancer, there was increased risk of breast cancer among postmenopausal women who were heterozygous for either of the two SMUG1 SNPs (odds ratio (OR) 1.29, 95% confidence interval (CI) 1.07-1.56) and OR 1.29, 95% CI 1.07-1.55, respectively). Among premenopausal women, increased risk associated with the SMUG1 rs2029166 genotype was limited to those with low folate intake. There were no other interactions with vitamins B(6) or B(12) intake.

CONCLUSIONS

Our study suggests that the four selected SNPs are not robust determinants of breast cancer risk, but that the two SNPs in SMUG1 might modestly alter the risk of breast cancer. However, the increase in risk among heterozygotes in the two SNPs in SMUG1, which is thought to be the most active glycosylase in vivo, raises the possibility that subtle 'heterosis' effects on cancer risk might be produced by these SNPs.

Association of androgen receptor CAG repeat polymorphism with VO₂max response to hypoxic training in North China Han men

The purposes of this study were to investigate the distribution characteristics of CAG repeat polymorphism in exon 1 of androgen receptor gene and the association of CAG polymorphism with VO₂max response to hypoxic training in North China Han men. Sixty-five healthy young men completed a 30-day HiHiLo training (living high, exercise high and training low) in a simulated normobaric hypoxic environment. All subjects slept in 14.3-14.8% O₂ concentration, and participated in hypoxic training three times a week in 15.4% O₂ concentration. VO₂max (peak oxygen consumption) and body weight were measured before and after hypoxic training. A total of 15 repeat alleles were observed by CAG genotype analyze, in which (CAG)22 was most common. When using 21 and 22 alleles, respectively, as cut-off points, we found that the baseline body weight of two shorter genotype groups was significantly lower than that of longer ones, and that the ΔVO₂max and ΔrVO₂max (Δrelative value of VO₂max) of two shorter genotype groups were significantly higher than those of longer ones after hypoxic training. These findings indicated that AR CAG repeat polymorphism was associated with the exercise performance after simulated normobaric hypoxic HiHiLo training in North China Han men, and that the shorter genotypes had a better individual response to hypoxic training.

800 facets of retinal degeneration

In today's world of genomics and large computational analyses, rapid progress has been made in identifying genes associated with human retinal diseases. Nevertheless, before significant advances toward effective therapeutic intervention is made, a clearer understanding of the molecular and cellular role of these gene products in normal and diseased photoreceptor cell biology is required. Given the complexity of the vertebrate retina, these advancements are unlikely to be revealed in isolated human cell lines, but instead, will require the use of numerous model systems. Here, we describe several parallels between vertebrate and invertebrate photoreceptor cell biology that are beginning to emerge and advocate the use of Drosophila melanogaster as a powerful genetic model system for uncovering molecular mechanisms of human retinal pathologies, in particular photoreceptor neurodegeneration.

Comparative genomics-guided loop-mediated isothermal amplification for characterization of Pseudomonas syringae pv. phaseolicola

AIMS

To design and evaluate a loop-mediated isothermal amplification (LAMP) protocol by combining comparative genomics and bioinformatics for characterization of Pseudomonas syringae pv. phaseolicola (PSP), the causal agent of halo blight disease of bean (Phaseolus vulgaris L.).

METHODS AND RESULTS

Genomic sequences of Pseudomonas syringae pathovars, P. fluorescens and P. aeruginosa were analysed using multiple sequence alignment. A pathovar-specific region encoding pathogenicity-related secondary metabolites in the PSP genome was targeted for developing a LAMP assay. The final assay targeted a polyketide synthase gene, and readily differentiated PSP strains from other Pseudomonas syringae pathovars and other Pseudomonas species, as well as other plant pathogenic bacteria, e.g. species of Pectobacterium, Erwinia and Pantoea.

CONCLUSION

A LAMP assay has been developed for rapid and specific characterization and identification of PSP from other pathovars of P. syringae and other plant-associated bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY

This paper describes an approach combining a bioinformatic data mining strategy and comparative genomics with the LAMP technology for characterization and identification of a plant pathogenic bacterium. The LAMP assay could serve as a rapid protocol for microbial identification and detection with significant applications in agriculture and environmental sciences.

Activation of liver X receptors inhibits pancreatic islet beta cell proliferation through cell cycle arrest

AIMS/HYPOTHESIS

Liver X receptors (LXRs) are important transcriptional regulators of lipid homeostasis and proliferation in several cell types. However, the roles of LXRs in pancreatic beta cells have not been fully established. The aim of this study was to investigate the effects of LXRs on pancreatic beta cell proliferation.

METHODS

Gene expression was analysed using real-time RT-PCR. Transient transfection and reporter gene assays were used to determine the transcriptional activity of LXRs in pancreatic beta cells. Cell viability and proliferation were analysed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), DNA fluorometric, BrdU labelling and [(3)H]thymidine incorporation assays. Cell cycle distribution was investigated by flow cytometry analysis. Adenovirus-based RNA interference was used to knockdown LXRalpha, LXRbeta and p27 in MIN6 cells and mouse islets.

RESULTS

We found that both Lxralpha (also known as Nr1h3) and Lxrbeta (also known as Nr1h2) were expressed and transactivated the LXR response element in HIT-T15 and MIN6 cells. Activation of LXRs dose-dependently inhibited pancreatic beta cell viability and proliferation. This was accompanied by beta cell cycle arrest at the G1 phase. Furthermore, LXR activation increased levels of the p27 protein by inhibiting its degradation. Knockdown of p27 reversed these effects of LXR activation on growth inhibition and cell cycle arrest.

CONCLUSIONS/INTERPRETATION

Our observations indicate that LXR activation inhibits pancreatic beta cell proliferation through cell cycle arrest. A well-known regulator of pancreatic beta cell cycle progression, p27, is upregulated and mediates the effects of LXRs on growth inhibition in beta cells. These observations suggest the involvement of aberrant activation of LXR in beta cell mass inadequacy, which is an important step in the development of type 2 diabetes.

Anomalous line shape of the cross section for e{+}e{-}--> hadrons in the center-of-mass energy region between 3.650 and 3.872 GeV

We observe an obvious anomalous line shape of the e;{+}e;{-}--> hadrons total cross sections in the energy region between 3.700 and 3.872 GeV. It is inconsistent with the explanation for only one simple psi(3770) resonance with a statistical significance of 7sigma. The anomalous line shape may be explained by two possible enhancements of the inclusive hadron production near the center-of-mass energies of 3.764 and 3.779 GeV, indicating that either there is likely a new structure in addition to the psi(3770) resonance around 3.773 GeV, or there are some physics effects reflecting the DD[over ] production dynamics.

Segmentation of touching cell nuclei using gradient flow tracking

Reliable cell nuclei segmentation is an important yet unresolved problem in biological imaging studies. This paper presents a novel computerized method for robust cell nuclei segmentation based on gradient flow tracking. This method is composed of three key steps: (1) generate a diffused gradient vector flow field; (2) perform a gradient flow tracking procedure to attract points to the basin of a sink; and (3) separate the image into small regions, each containing one nucleus and nearby peripheral background, and perform local adaptive thresholding in each small region to extract the cell nucleus from the background. To show the generality of the proposed method, we report the validation and experimental results using microscopic image data sets from three research labs, with both over-segmentation and under-segmentation rates below 3%. In particular, this method is able to segment closely juxtaposed or clustered cell nuclei, with high sensitivity and specificity in different situations.

Search for the invisible decay of J/psi in psi(2S) --> pi(+)pi(-) J/psi

Using psi(2S) --> pi(+)pi(-) J/psi events in a sample of 14.0 x 10(6) psi(2S) decays collected with the BES-II detector, a search for the decay of the J/psi to invisible final states is performed. No signal is found, and an upper limit at the 90% confidence level is determined to be 1.2 x 10(-2) for the ratio B(J/psi --> invisible)/B(J/psi-->mu(+)mu(-)). This is the first search for J/psi decays to invisible final states.

Observation of Y(2175) in J/psi --> etaphif0 (980)

The decays of J/psi --> etaphif(0)(980)[eta --> gammagamma, phi --> K(+) K(-), f(0)(980) --> pi(+)pi(-)] are analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector at the Beijing Electron-Positron Collider. A structure at around 2.18 GeV/c(2) with about 5 sigma significance is observed in the phif(0)(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m = 2.186+/-0.010(stat)+/-0.006(syst) GeV/c(2) and Gamma = 0.065+/-0.023(stat)+/-0.017(syst) GeV/c(2), respectively, which are consistent with those of Y(2175), observed by the BABAR Collaboration in the initial-state radiation process e(+)e(-) --> gamma(ISR) phif(0)(980). The production branching ratio is determined to be Br(J/psi --> etaY(2175))Br(Y(2175)- -> phif(0)(980))Br(f(0)(980) --> pi(+)pi(-)) = [3.23+/-0.75(stat)+/-0.73(syst)] x 10(-4), assuming that the Y(2175) is a 1(--) state.

A dynamic channel assignment policy through Q-learning

One of the fundamental issues in the operation of a mobile communication system is the assignment of channels to cells and to calls. Since the number of channels allocated to a mobile communication system is limited, efficient utilization of these communication channels by using efficient channel assignment strategies is not only desirable but also imperative. This paper presents a novel approach to solving the dynamic channel assignment (DCA) problem by using a form of realtime reinforcement learning known as Q-learning in conjunction with neural network representation. Instead of relying on a known teacher, the system is designed to learn an optimal channel assignment policy by directly interacting with the mobile communication environment. The performance of the Q-learning-based DCA was examined by extensive simulation studies on a 49-cell mobile communication system under various conditions. Comparative studies with the fixed channel assignment (FCA) scheme and one of the best dynamic channel assignment strategies, MAXAVAIL, have revealed that the proposed approach is able to perform better than the FCA in various situations and capable of achieving a performance similar to that achieved by the MAXIAVIAL, but with a significantly reduced computational complexity.

Smad7 gene transfer inhibits peritoneal fibrosis

Fibrosis mediated by transforming growth factor-beta (TGF-beta) is a common cause of peritoneal dialysis (PD) failure. In a model of peritoneal fibrosis, we tested the effect of Smad7, an inhibitor of TGF-beta signaling, using an ultrasound-microbubble-mediated delivery system. Rats were given daily PD for 4 weeks and received Smad7 or control plasmid transfer. The ultrasound technique enhanced Smad7 expression in a dose-dependent manner in more than 80% of the peritoneal cells after 3 days. The expression decreased by 14 days, but this was corrected by a second gene transfer. The overexpression of Smad7 substantially inhibited Smad2/3 activation, TGF-beta, plasminogen activator inhibitor-1, extracellular matrix, and myofibroblast mRNA, and protein expression in the peritoneal cells. The decreased peritoneal injury included the rise of mass transfer of glucose, a reduction of the ultrafiltration rate, and fibrotic thickening. Our studies suggest that ultrasound-mediated Smad7 gene delivery may be useful in the prevention or treatment of dialysis-induced peritoneal fibrosis.

Measurement of psi2S radiative decays

Using 14 x 10(6) psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gammapp, gamma2(pi+pi-), gammaKS0K+pi-+c.c., gammaK+K-pi+pi-, gammaK*0K-pi++c.c., gammaK*0K*0, gammapi+pi-pp, gamma2(K+K-), gamma3(pi+pi-), and gamma2(pi+pi-)K+K- with the invariant mass of hadrons below 2.9 GeV/c2. We also report branching fractions of psi(2S) decays into 2(pi+pi-)pi0, omegapi+pi-, omegaf2(1270), b1+/-pi-/+, and pi02(pi+pi-)K+K-.

Measurements of the continuum R(uds) and R values in e(+)e(-) annihilation in the energy region between 3.650 and 3.872 GeV

We report measurements of the continuum R(uds) near the center-of-mass energy of 3.70 GeV, the R[uds(c)+psi(3770)](s) and the R(had)(s) values in e(+)e(-) annihilation at 68 energy points in the energy region between 3.650 and 3.872 GeV with the BES-II detector at the BEPC Collider. We obtain the R(uds) for the continuum light hadron (containing u, d, and s quarks) production near the DD threshold to be R(uds)=2.141+/-0.025+/-0.085.

Histone deacetylase 3 interacts with and deacetylates myocyte enhancer factor 2

The myocyte enhancer factor 2 (MEF2) family of transcription factors is not only important for controlling gene expression in normal cellular programs, like muscle differentiation, T-cell apoptosis, neuronal survival, and synaptic differentiation, but has also been linked to cardiac hypertrophy and other pathological conditions. Lysine acetylation has been shown to modulate MEF2 function, but it is not so clear which deacetylase(s) is involved. We report here that treatment of HEK293 cells with trichostatin A or nicotinamide upregulated MEF2D acetylation, suggesting that different deacetylases catalyze the deacetylation. Related to the trichostatin A sensitivity, histone deacetylase 4 (HDAC4) and HDAC5, two known partners of MEF2, exhibited little deacetylase activity towards MEF2D. In contrast, HDAC3 efficiently deacetylated MEF2D in vitro and in vivo. This was specific, since HDAC1, HDAC2, and HDAC8 failed to do so. While HDAC4, HDAC5, HDAC7, and HDAC9 are known to recognize primarily the MEF2-specific domain, we found that HDAC3 interacts directly with the MADS box. In addition, HDAC3 associated with the acetyltransferases p300 and p300/CBP-associated factor (PCAF) to reverse autoacetylation. Furthermore, the nuclear receptor corepressor SMRT (silencing mediator of retinoid acid and thyroid hormone receptor) stimulated the deacetylase activity of HDAC3 towards MEF2 and PCAF. Supporting the physical interaction and deacetylase activity, HDAC3 repressed MEF2-dependent transcription and inhibited myogenesis. These results reveal an unexpected role for HDAC3 and suggest a novel pathway through which MEF2 activity is controlled in vivo.

Search for invisible decays of eta and eta' in J/psi --> phi eta and phi eta'

Using a data sample of 58 x 10(6) J/psi decays collected with the Beijing Spectrometer II detector at the Beijing Electron Positron Collider, searches for invisible decays of eta and eta' in J/psi to phi eta and phi eta' are performed. The phi signals, which are reconstructed in K+K- final states, are used to tag the eta and eta' decays. No signals are found for the invisible decays of either eta or eta', and upper limits at the 90% confidence level are determined to be 1.65 x 10(-3) for the ratio B(eta-->invisible)/B(eta --> gamma gamma) and 6.69 x 10(-2) for B(eta' --> invisible)/B(eta' --> gammagamma). These are the first searches for eta and eta' decays into invisible final states.

Identification, Characterization, and Molecular Detection of Alfalfa mosaic virus in Potato

ABSTRACT Alfalfa mosaic virus (AMV) was detected in potato fields in several provinces in Canada and characterized by bioassay, enzyme-linked immunosorbent assay, and reverse-transcription polymerase chain reaction (RT-PCR). The identity of eight Canadian potato AMV isolates was confirmed by sequence analysis of their coat protein (CP) gene. Sequence and phylogenetic analysis indicated that these eight AMV potato isolates fell into one strain group, whereas a slight difference between Ca175 and the other Canadian AMV isolates was revealed. The Canadian AMV isolates, except Ca175, clustered together among other strains based on alignment of the CP gene sequence. To detect the virus, a pair of primers, AMV-F and AMV-R, specific to the AMV CP gene, was designed based on the nucleotide sequence alignment of known AMV strains. Evaluations showed that RT-PCR using this primer set was specific and sensitive for detecting AMV in potato leaf and tuber samples. AMV RNAs were easily detected in composite samples of 400 to 800 potato leaves or 200 to 400 tubers. Restriction analysis of PCR amplicons with SacI was a simple method for the confirmation of PCR tests. Thus, RT-PCR followed by restriction fragment length polymorphism analysis may be a useful approach for screening potato samples on a large scale for the presence of AMV.

Observation of a broad 1-- resonant structure around 1.5 GeV/c2 in the K+K- mass spectrum in J/psi-->K+K-pi0

A broad peak is observed at low K+K- invariant mass in J/psi-->K+K-pi(0) decays found in a sample of 5.8x10(7) J/psi events collected with the BESII detector. The statistical significance of the broad resonance is much larger than 5sigma. A partial wave analysis shows that the J;{PC} of this structure is 1--. Its pole position is determined to be [1576(-55)(+49)(stat)-91+98(syst)] MeV/c(2)-i/2[818(-23)(+22)(stat)-133+64(syst)] MeV/c(2). These parameters are not compatible with any known meson resonances.

Measurements of the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and the resonance parameters of psi(3770) and psi(2S)

We measure the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and non-DD[over ] to be (46.7+/-4.7+/-2.3)%, (36.9+/-3.7+/-2.8)%, (83.6+/-7.3+/-4.2)%, and (16.4+/-7.3+/-4.2)%, respectively. The resonance parameters of psi(3770) and psi(2S) are measured to be M_(psi(3770))=3772.2+/-0.7+/-0.3 MeV, Gamma_(psi(3770))(tot)=26.9+/-2.4+/-0.3 MeV, and Gamma_(psi(3770))(ee)=251+/-26+/-11 eV; M_(psi(2S))=3685.5+/-0.0+/-0.3 MeV, Gamma_(psi(2S))(tot)=331+/-58+/-2 keV, and Gamma_(psi(2S))(ee)=2.330+/-0.036+/-0.110 keV. We also measure the light hadron R value to be R(uds)=2.262+/-0.054+/-0.109 in the energy region from 3.660 to 3.872 GeV.

Changes in serum cardiac troponins following a 21-km run in junior male runners

AIM

This study was designed to examine the appearance and clearance characteristics of serum cardiac troponin T (cTnT) and I (cTnI) in junior runners after an exhaustive 21-km run. The dependence of the alternations of the cardiac troponins on the runners' training status reflected in training years, running ability and physiological profile at ventilatory threshold (Th(vent)) was also examined.

METHODS

Ten trained male adolescents (16.2+/-0.6 years) performed 21-km run and graded treadmill exercise with maximum effort on two different days. cTnT and cTnI immediately before and 2, 4 and 24 hours after exercise were measured in the 21-km trial. The parameters at Thvent including the running speed (Th(vent)-Speed) and VO2 (Th(vent)-VO2) were identified in the graded exercise trial.

RESULTS

Serum cTnT and cTnI in 6 of the 10 subjects measured 4 hours after the 21-km run were above the myocardial injury cutoffs of 0.03 and 0.09 ng x mL(-1), respectively, but returned towards pre-exercise levels within 24 hours that were not in the same manner observed in the clinical situation of myocardial infraction. The 6 subjects' training status was generally lower than that of the rest 4. Further, subjects' 4-h serum cTnT and cTnI were negatively related to their training years, Th(vent)-Speed and Th(vent)-VO2, and positively related to their personal best in half- and full-marathon races (r2 = or > 36%, n = 10).

CONCLUSIONS

Such findings implied that clinicians based the diagnosis of long-distance run-induced myocardial infraction in novice junior runners upon the transient postexercise elevations of cardiac troponins alone should be with caution.