Interaction between mDia1 and ROCK in Rho-induced migration and adhesion of human dental pulp cells

AIM

To investigate the effects of mammalian homologue of Drosophila diaphanous-1(mDia1) and Rho-associated coiled-coil-containing protein kinase (ROCK) on the migration and adhesion of dental pulp cells (DPCs).

METHODOLOGY

Lysophosphatidic acid (LPA) was used to activate Rho signalling. mDia1 and ROCK were inhibited by short interfering RNA and the specific inhibitor, Y-27632, respectively. The migration of DPCs was assessed using the transwell migration assay and scratch test. Formation of cytoskeleton and focal adhesions(FAs) was observed by confocal laser scanning microscopy. Cell adhesion and spreading assays were performed. Phosphorylation of focal adhesion kinase (FAK) and paxillin was detected by Western blotting, and the bands were analysed using Adobe Photoshop CS5 software. All experiments were performed at least three times, and data were analysed with one-way anova and a post hoc test.

RESULTS

LPA-triggered activation of Rho and inhibition of ROCK significantly increased the cell migration rate. Cell migration was inhibited by silencing mDia1. mDia1 silencing and ROCK inhibition suppressed the LPA-induced formation of the cytoskeleton, FA and phosphorylation of FAK and paxillin. Inhibition of ROCK or mDia1 facilitated early cell adhesion and spreading; by contrast, the combined inhibition of ROCK and mDia1 neutralized these effects.

CONCLUSIONS

mDia1 promoted RhoA-induced migration of DPCs, but ROCK had an opposite effect. Both mDia1 and ROCK participated in cytoskeleton formation and adhesion of DPCs. The interactions between mDia1 and ROCK might influence dental pulp repair by determining the migration and adhesion of DPCs.

Observation of a Neutral Structure near the DD[over ¯]^{*} Mass Threshold in e^{+}e^{-}→(DD[over ¯]^{*})^{0}π^{0} at sqrt[s]=4.226 and 4.257 GeV

A neutral structure in the DD[over ¯]^{*} system around the DD[over ¯]^{*} mass threshold is observed with a statistical significance greater than 10σ in the processes e^{+}e^{-}→D^{+}D^{*-}π^{0}+c.c. and e^{+}e^{-}→D^{0}D[over ¯]^{*0}π^{0}+c.c. at sqrt[s]=4.226 and 4.257 GeV in the BESIII experiment. The structure is denoted as Z_{c}(3885)^{0}. Assuming the presence of a resonance, its pole mass and width are determined to be [3885.7_{-5.7}^{+4.3}(stat)±8.4(syst)]  MeV/c^{2} and [35_{-12}^{+11}(stat)±15(syst)]  MeV, respectively. The Born cross sections are measured to be σ[e^{+}e^{-}→Z_{c}(3885)^{0}π^{0},Z_{c}(3885)^{0}→DD[over ¯]^{*}]=[77±13(stat)±17(syst)]  pb at 4.226 GeV and [47±9(stat)±10(syst)]  pb at 4.257 GeV. The ratio of decay rates B[Z_{c}(3885)^{0}→D^{+}D^{*-}+c.c.]/B[Z_{c}(3885)^{0}→D^{0}D[over ¯]^{*0}+c.c.] is determined to be 0.96±0.18(stat)±0.12(syst), consistent with no isospin violation in the process, Z_{c}(3885)^{0}→DD[over ¯]^{*}.

Measurement of the Absolute Branching Fraction for Λ_{c}^{+}→Λe^{+}ν_{e}

We report the first measurement of the absolute branching fraction for Λ_{c}^{+}→Λe^{+}ν_{e}. This measurement is based on 567  pb^{-1} of e^{+}e^{-} annihilation data produced at sqrt[s]=4.599  GeV, which is just above the Λ_{c}^{+}Λ[over ¯]_{c}^{-} threshold. The data were collected with the BESIII detector at the BEPCII storage rings. The branching fraction is determined to be B(Λ_{c}^{+}→Λe^{+}ν_{e})=[3.63±0.38(stat)±0.20(syst)]%, representing a significant improvement in precision over the current indirect determination. As the branching fraction for Λ_{c}^{+}→Λe^{+}ν_{e} is the benchmark for those of other Λ_{c}^{+} semileptonic channels, our result provides a unique test of different theoretical models, which is the most stringent to date.

Gingival fibroblasts resist apoptosis in response to oxidative stress in a model of periodontal diseases

Periodontal diseases are classified as inflammation affecting the supporting tissue of teeth, which eventually leads to tooth loss. Mild reversible gingivitis and severe irreversible periodontitis are the most common periodontal diseases. Periodontal pathogens initiate the diseases. The bacterial toxin, lipopolysaccharide (LPS), triggers the inflammatory response and leads to oxidative stress. However, the progress of oxidative stress in periodontal diseases is unknown. The purpose of this study is to examine oxidative stress and cell damage in gingivitis and periodontitis. Our results showed that LPS increases reactive oxygen species (ROS) accumulation in gingival fibroblast (GF). However, oxidative stress resulting from excessive ROS did not influence DNA damage and cell apoptosis within 24 h. The mechanism may be related to the increased expression of DNA repair genes, Ogg1, Neil1 and Rad50. Detection of apoptosis-related proteins also showed anti-apoptotic effects and pro-apoptotic effects were balanced. The earliest damage appeared in DNA when increased γH2AX, an early biomarker for DNA damage, was detected in the LPS group after 48 h. Later, when recurrent inflammation persisted, 8-OHdG, a biomarker for oxidative stress was much higher in periodontitis model compared to the control in vivo. Staining of 8-OHdG in human periodontitis specimens confirmed the results. Furthermore, TUNEL staining of apoptotic cells indicated that the periodontitis model induced more cell apoptosis in gingival tissue. This suggested GF could resist early and acute inflammation (gingivitis), which was regarded as reversible, but recurrent and chronic inflammation (periodontitis) led to permanent cell damage and death.

Observation of a Neutral Charmoniumlike State Z_{c}(4025)^{0} in e^{+}e^{-}→(D^{*}D[over ¯]^{*})^{0}π^{0}

We report a study of the process e^{+}e^{-}→(D^{*}D[over ¯]^{*})^{0}π^{0} using e^{+}e^{-} collision data samples with integrated luminosities of 1092 pb^{-1} at sqrt[s]=4.23 GeV and 826 pb^{-1} at sqrt[s]=4.26 GeV collected with the BESIII detector at the BEPCII storage ring. We observe a new neutral structure near the (D^{*}D[over ¯]^{*})^{0} mass threshold in the π^{0} recoil mass spectrum, which we denote as Z_{c}(4025)^{0}. Assuming a Breit-Wigner line shape, its pole mass and pole width are determined to be (4025.5_{-4.7}^{+2.0}±3.1) MeV/c^{2} and (23.0±6.0±1.0) MeV, respectively. The Born cross sections of e^{+}e^{-}→Z_{c}(4025)^{0}π^{0}→(D^{*}D[over ¯]^{*})^{0}π^{0} are measured to be (61.6±8.2±9.0) pb at sqrt[s]=4.23 GeV and (43.4±8.0±5.4) pb at sqrt[s]=4.26 GeV. The first uncertainties are statistical and the second are systematic.

New measurement of antineutrino oscillation with the full detector configuration at Daya Bay

We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^{5} GW_{th}  ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^{241}Am-^{13}C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin^{2}2θ_{13} and |Δm_{ee}^{2}| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^{2}2θ_{13}=0.084±0.005 and |Δm_{ee}^{2}|=(2.42±0.11)×10^{-3}  eV^{2} in the three-neutrino framework.

Observation of Z_{c}(3900)^{0} in e^{+}e^{-}→π^{0}π^{0}J/ψ

Using a data sample collected with the BESIII detector operating at the BEPCII storage ring, we observe a new neutral state Z_{c}(3900)^{0} with a significance of 10.4σ. The mass and width are measured to be 3894.8±2.3±3.2  MeV/c^{2} and 29.6±8.2±8.2  MeV, respectively, where the first error is statistical and the second systematic. The Born cross section for e^{+}e^{-}→π^{0}π^{0}J/ψ and the fraction of it attributable to π^{0}Z_{c}(3900)^{0}→π^{0}π^{0}J/ψ in the range E_{c.m.}=4.19-4.42  GeV are also determined. We interpret this state as the neutral partner of the four-quark candidate Z_{c}(3900)^{±}.

Observation and Spin-Parity Determination of the X(1835) in J/ψ→γK_{S}^{0}K_{S}^{0}η

We report an observation of the process J/ψ→γX(1835)→γK_{S}^{0}K_{S}^{0}η at low K_{S}^{0}K_{S}^{0} mass with a statistical significance larger than 12.9σ using a data sample of 1.31×10^{9} J/ψ events collected with the BESIII detector. In this region of phase space the K_{S}^{0}K_{S}^{0} system is dominantly produced through the f_{0}(980). By performing a partial wave analysis, we determine the spin parity of the X(1835) to be J^{PC}=0^{-+}. The mass and width of the observed X(1835) are 1844±9(stat)_{-25}^{+16}(syst)  MeV/c^{2} and 192_{-17}^{+20}(stat)_{-43}^{+62}(syst)  MeV, respectively, which are consistent with the results obtained by BESIII in the channel J/ψ→γπ^{+}π^{-}η^{'}.

Observation of the ψ(1 3D2) State in e+e-→π+π-γχc1 at BESIII

We report the observation of the X(3823) state in the process e+e-→π+π-X(3823)→π+π-γχc1 with a statistical significance of 6.2σ, in data samples at center-of-mass energies sqrt[s]=4.230, 4.260, 4.360, 4.420, and 4.600 GeV collected with the BESIII detector at the BEPCII electron positron collider. The measured mass of the X(3823) state is (3821.7±1.3±0.7)  MeV/c2, where the first error is statistical and the second systematic, and the width is less than 16 MeV at the 90% confidence level. The products of the Born cross sections for e+e-→π+π-X(3823) and the branching ratio B[X(3823)→γχc1,c2] are also measured. These measurements are in good agreement with the assignment of the X(3823) state as the ψ(1 3D2) charmonium state.

Tandem overexpression of five human factors renders murine hepatocytes susceptible to hepatitis C virus

Development of mouse model of hepatitis C virus (HCV) infection has great significance in drug screening and vaccine research. The barriers of interspecies transmission of HCV are increasingly better understood. Human factors, namely low-density lipoprotein receptor (hLDLR), CD81 (hCD81), scavenger receptor class B type I (hSCARB1), occludin (hOCLN) and claudin 1 (hCLDN1) are all required for rendering mouse hepatocytes permissive to HCV. With the aim to humanize mouse hepatocytes we constructed two recombinant vectors tandemly expressing the first three and the last two HCV entry factors mentioned above, respectively. Cotransfection of mouse hepatocytes with these vectors made them permissive to HCV binding and entry. Tandem overexpression of hLDLR, hSCARB1, hCD81, hCLDN1 and hOCLN is a novel approach to tailoring mouse hepatocytes to HCV binding and entry which can be further used to establish a mouse model of HCV infection as a basis for developing antiviral drugs and vaccines.

[Effect of ADAR1 on the development of MLL-AF9 induced murine AML]

OBJECTIVE

To establish the ADAR1 (adenosine deaminase that act on RNA 1) knockout MLL-AF9 acute myeloid leukemia (AML) mouse model, and to preliminarily investigate the effects of ADAR1 deletion on the development of AML.

METHODS

The lineage⁻ (Lin⁻) cells of ER-CreADAR1(lox/lox) mice and their ADAR1(lox/lox) counterparts were enriched by magnetic activated cell sorting (MACS) and then transduced with retrovirus carrying MSCV- MLL/AF9-IRES-GFP fusion gene. The efficiency of transduction was detected by flow cytometry, and equal number of GFP⁺ cells were transplanted into lethally irradiated recipient mice. The recipient mice were treated with tamoxifen at 48 hours after transplantation to induce ADAR1 knockout and divided into following groups: experimental group (ER-Cre;ADAR1(lox/lox)+tamoxifen), control groups ((1)ER-Cre;ADAR1(lox/lox)+vechile, (2)ADAR1(lox/lox)+tamoxifen, (3)ADAR1(lox/lox)+vechile). The percentage of GFP⁺ cells in peripheral blood was examined at 10, 15 and 20 days respectively after transplantation and the survival of the recipient mice was observed. In vitro study, ER-Cre;ADAR1(lox/lox) and ADAR1(lox/lox) AML cells were cultured and the apoptosis rates of these cells 48 hours after 4-hydroxytamoxifen treatment were examined.

RESULTS

The ADAR1 deletion MLL-AF9 AML mouse model was successfully established. Deletion of ADAR1 could decrease the percentage of GFP⁺ cells in the peripheral blood and significantly prolong the survival rate of recipient mice（P<0.05）. In vitro study showed that the cultured total cell number, percentage of GFP⁺ cells decreased and the apoptosis rate of AML cells increased.

CONCLUSION

Ablation of ADAR1 could delay the progression of AML in recipient mice. ADAR1 plays a critical role in the development and maintenance of murine MLL-AF9 AML.

La-related protein 4B maintains murine MLL-AF9 leukemia stem cell self-renewal by regulating cell cycle progression

Our recent study identified a nonsense mutation of La-related protein 4B (LARP4B) from whole genome sequencing of a 3-year-old female monozygotic twin pair discordant for MLL-associated acute myeloid leukemia (AML). To study the role of LARP4B in AML, we established a LARP4B-knockdown MLL-AF9 AML mouse model. Using this mouse model, we found that LARP4B knockdown significantly decreased leukemia cells in the peripheral blood, spleen, and bone marrow and prolonged the survival of AML recipient mice. Additional studies showed that LARP4B knockdown reduced leukemia stem cells (LSCs) and impaired the self-renew capacity of LSCs. Cell cycle analysis revealed that LARP4B knockdown arrested more LSCs in the G0 phase. The transcription of the cell cycle inhibitors p16, p19, and p21 and of the lineage-specific transcription factor CCAAT-enhancer-binding protein α was increased in the LARP4B-knockdown LSCs. Thus, our results demonstrate that LARP4B plays an important role in the maintenance of LSCs and suggest that LARP4B may regulate the cell cycle of LSCs via suppressing the expression of the cell cycle inhibitors p16, p19, and p21 and the myeloid specific transcription factor CCAAT-enhancer-binding protein α.

Phosphoinositide-dependent kinase 1 regulates leukemia stem cell maintenance in MLL-AF9-induced murine acute myeloid leukemia

Although great efforts have been made to improve available therapies, the mortality rate of acute myeloid leukemia (AML) remains high due to poor treatment response and frequent relapse after chemotherapy. Leukemia stem cells (LSCs) are thought to account for this poor prognosis and relapse. Phosphoinositide-dependent kinase 1 (PDK1) is a critical regulator of the PI3K/Akt pathway and has been shown to be frequently activated in leukemia. However, the role of PDK1 in the regulation of LSCs in AML is still not clear. Using a PDK1 conditional deletion MLL-AF9 murine AML model, we revealed that the deletion of PDK1 prolonged the survival of AML mice by inducing LSC apoptosis. This was accompanied by the increased expression of the pro-apoptotic genes Bax and p53 and the reduced expression of Stat5, which has been shown to be constitutively activated in leukemia. Thus, our findings suggest that PDK1 plays an essential role in maintaining LSCs. Further delineating the function of PDK1 in LSCs may provide a new strategy for the improved treatment of AML relapse.

Study of e(+)e(-)→ωχ(cJ) at center of mass energies from 4.21 to 4.42 GeV

Based on data samples collected with the BESIII detector at the BEPCII collider at nine center of mass energies from 4.21 to 4.42 GeV, we search for the production of e^{+}e^{-}→ωχ_{cJ} (J=0, 1, 2). The process e^{+}e^{-}→ωχ_{c0} is observed for the first time, and the Born cross sections at sqrt[s]=4.23 and 4.26 GeV are measured to be (55.4±6.0±5.9) and (23.7±5.3±3.5)  pb, respectively, where the first uncertainties are statistical and the second are systematic. The ωχ_{c0} signals at the other seven energies and the e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} signals are not significant, and the upper limits on the cross sections are determined. By examining the ωχ_{c0} cross section as a function of center of mass energy, we find that it is inconsistent with the line shape of the Y(4260) observed in e^{+}e^{-}→π^{+}π^{-}J/ψ. Assuming the ωχ_{c0} signals come from a single resonance, we extract the mass and width of the resonance to be (4230±8±6)  MeV/c^{2} and (38±12±2)  MeV, respectively, and the statistical significance is more than 9σ.

Which measures of adiposity predict subsequent left ventricular geometry? Evidence from the Bogalusa Heart Study

BACKGROUND AND AIMS

Left ventricular (LV) hypertrophy increases the risk of future cardiovascular events. The relationship between obesity in young adulthood and later LV geometry is unknown. We examined the association between long-term changes in measures of adiposity and subsequent LV geometry among 1073 young adults from the Bogalusa Heart Study.

METHODS AND RESULTS

Echocardiography-measured LV geometry was classified into normal (N = 796), concentric remodeling (N = 124), eccentric hypertrophy (N = 99), and concentric hypertrophy (N = 54) by integrating relative wall thickness and LV mass index. The mean age of our population was 38 years when the LV geometry was measured. Body mass index (BMI) increased by a mean of 4.9 kg/m(2) over a median of 20 years, waist circumference (WC) by 10.9 cm over 17 years, waist/hip ratio by 0.02 over 10 years, waist/height ratio by 0.06 over 17 years, abdominal height by 0.9 cm over 10 years, body fat (BF) percentage by 12.7% over 20 years, and Visceral Adiposity Index by 0.30 over 17 years. In polytomous logistic regression models corrected for multiple comparisons, participants with one-standard-deviation increases in BMI, WC, waist/height ratio, and BF had 2.00 (95% confidence interval (CI): 1.53-2.61), 1.33 (1.06-1.68), 1.35 (1.07-1.70), and 1.60 (1.26-2.03) times the risk of eccentric hypertrophy, respectively, after adjustment for demographic, lifestyle, metabolic risk factors, and follow-up time. Likewise, the rates of change in BMI, WC, waist/height ratio, and BF were associated with eccentric hypertrophy. There was no association with concentric remodeling or concentric hypertrophy.

CONCLUSIONS

Our findings suggest that increases in BMI, WC, waist/height ratio, and BF were strong predictors of eccentric hypertrophy in middle age.

BEP for high-risk gestational trophoblastic tumor: results from a cohort of 45 patients

AIM

To evaluate the effectiveness and safety of combination chemotherapy of bleomycin, etoposide, and cisplatin (BEP) regimen in patients with high-risk gestational trophoblastic neoplasia (GTN).

MATERIALS AND METHODS

The authors analyzed the clinical response, toxicity, and the occurrence of secondary tumors of 45 patients with high-risk GTN under BEP.

RESULTS

The total complete remission (CR) rate of BEP regimen was 88.89% (40/45). Five patients developed drug-resistance after average 4.8 courses of BEP, and the regimen converted to etoposide, methotrexate, and dactinomycin (EMA)/cyclophosphamide and vincristine sulfate (CO). Ultimately, four cases achieved CR and one case died of cancer. There were no severe anaphylaxis and obvious impairment of cardiac, liver, pulmonary and kidney function, except one patient who developed grade IV bone marrow suppression and worsened pulmonary fibrosis after chemotherapy. None of survival patients developed secondary tumor during the follow-up.

CONCLUSION

For young high-risk GTN patients, BEP may represent a safe and effective regimen.

Addition of bevacizumab to neoadjuvant chemotherapy for Stage IV ovarian serous adenocarcinoma with multiple lymph node metastases: a case report

A 50-year-old female patient was diagnosed with Stage IV ovarian serous adenocarcinoma with multiple lymph node metastases. The CA-125 level normalized after four cycles of neoadjuvant chemotherapy (NACT) using paclitaxel, nedaplatin, and bevacizumab (BEV) before surgery. A positron emission tomography-computed tomography (PET-CT) scan showed significantly reduced bilateral adnexal masses after NACT fluorodeoxyglucose (FDG) metabolism in multiple lymph nodes was inhibited significantly, and the number and sites of metastatic lesions were decreased. The patient underwent optimal cytoreductive surgery. Chemotherapy was continued after surgery and image-guided radiation therapy (IGRT) (40 Gy) was applied for the remaining lymph nodes in the pelvic cavity and cervicothoracic region. No sign of recurrence has been observed in this patient nine months after surgery. The patient achieved a satisfactory outcome and no serious side effects were observed. Therefore, addition of BEV to NACT is a new method for the pre-operative treatment of advanced ovarian cancer.