Hypoxic condition promotes differentiation and mineralization of dental pulp cells in vivo

AIM

To investigate the behaviour of dental pulp cells under hypoxic conditions in vivo using an experimental animal model.

METHODOLOGY

A mini-screw was inserted into the inferior dental nerve canal of rats to arrest the blood supply, which resulted in a reduced oxygen level in the dental pulps of molar teeth used for the experimental group. The decrease in blood supply was evaluated by injected India ink in transparent specimens. The hypoxia marker hypoxyprobe-1 was investigated by immunohistochemical staining. The mRNA expressions of ATP-binding cassette transporter (ABC) G2 (ABCG2) which is a marker for the capacity to excrete metabolites and for stem-like cells as well as dentine sialophosphoprotein (DSPP) and osteocalcin (OCN) which are markers for mineralization were evaluated by RT-PCR. Protein was evaluated by immunohistochemical staining using ABCG2, dentine sialoprotein (DSP) and OCN.

RESULTS

The evaluation of India ink indicated a decreased blood supply in the transparent specimens, and hypoxyprobe-1 immunohistochemical staining showed positive expression. ABCG2, DSPP and OCN mRNA expressions increased at 7 and 14 days. Immunohistochemically, ABCG2, DSP and OCN-positive cells were localized in the odontoblastic layer.

CONCLUSIONS

Hypoxic conditions promoted mineralization and differentiation of dental pulp cells of the odontoblastic layer.

A catecholamine-secreting neuroblastoma leading to hydrops fetalis

A case of fetal neuroblastoma of the right adrenal gland, with rapid development of hydrops fetalis due to catecholamine-induced cardiomyopathy, is reported. A fetus with a right suprarenal mass detected during ultrasonography at 32 weeks gestation progressively developed into hydrops fetalis by 35.2 weeks gestation. An emergent cesarean section was performed. At birth, the female neonate was hypertensive, with markedly elevated catecholamine levels; echocardiography showed poor contractility. Morphine, human atrial natriuretic peptide, milrinone, nitroprusside and dobutamine were initiated and her blood pressure was maintained within the normal range and her cardiac contractility improved 2 weeks after birth. Neuroblastoma cells were detected in the placenta, resulting in the right adrenal mass being diagnosed as a neuroblastoma. She was well, and the mass diminished in size within 4 months, without surgery. A fetus with suspected neuroblastoma, indicated by a suprarenal mass, should be managed with appropriate consideration of hydrops.

Fast visible imaging and edge turbulence analysis in QUEST

A fast visible imaging system is installed on the spherical tokamak QUEST to study edge turbulence. The camera uses a complementary metal-oxide semiconductor detector with a maximum resolution of 1024 × 1024 at 7000 frames∕s (fps) and can achieve 775 kfps at a resolution of 128 × 24. In this paper, we present the salient features of the system and its application to study edge turbulence in 8.2 GHz ECRH driven slab plasma, without plasma current. Vertical magnetic field (B(z)) topology is varied with three sets of poloidal field (PF) coils and the variation in the edge turbulence is investigated as a function of the B(z) strength and curvature. Fluctuation amplitude was highest for the shallow PF well. Cross-correlation coefficient shows distinct coherent mode along z direction at the steep density gradient region and it grows with the PF mirror ratio.

Search for the Θ+ pentaquark via the π(-)p→K(-)X reaction at 1.92 GeV/c

The Θ(+) pentaquark baryon was searched for via the π(-)p→K(-)X reaction with a missing mass resolution of 1.4 MeV/c(2) (FWHM) at the Japan Proton Accelerator Research Complex (J-PARC). π(-) meson beams were incident on the liquid hydrogen target with a beam momentum of 1.92 GeV/c. No peak structure corresponding to the Θ(+) mass was observed. The upper limit of the production cross section averaged over the scattering angle of 2° to 15° in the laboratory frame is obtained to be 0.26 μb/sr in the mass region of 1.51-1.55 GeV/c(2). The upper limit of the Θ(+) decay width is obtained to be 0.72 and 3.1 MeV for J(Θ)(P)=1/2(+) and J(Θ)(P)=1/2(-), respectively, using the effective Lagrangian approach.

Investigation of a high spatial resolution method based on polar coordinate maximum entropy method for analyzing electron density fluctuation data measured by laser phase contrast

Laser phase contrast is a powerful diagnostic method to determine the spatial distribution of electron density fluctuations in magnetically confined plasmas, although its applicability depends on magnetic field configurations. The spatial resolution of fluctuations is linked with the resolution of the propagation direction that is derived from the two-dimensional spectral analysis of the wavenumber for the fluctuations. The method was applied to fluctuation measurements in a compact helical system. In order to improve the resolution of the propagation direction with a relatively small number of data points, the maximum entropy method with polar coordinates was employed. A spatial resolution of the order of 1 cm was obtained, which is satisfactory in a plasma with a 20 cm minor radius.

Indication of electron neutrino appearance from an accelerator-produced off-axis muon neutrino beam

The T2K experiment observes indications of ν(μ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3)  eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

Intracellular bacteria recognition contributes to maximal interleukin (IL)-12 production by IL-10-deficient macrophages

Interleukin (IL)-12 is a key factor that induces T helper cell type 1-mediated immunity and inflammatory diseases. In some colitis models, such as IL-10 knock-out (KO) mice, IL-12 triggers intestinal inflammation. An abundant amount of IL-12 is produced by intestinal macrophages in response to stimulation by commensal bacteria in IL-10 KO mice. Intact bacteria are more potent inducers of macrophage IL-12 production than cell surface components in this model. This suggested that cell surface receptor signalling and intracellular pathogen recognition mechanisms are important for the induction of IL-12. We addressed the importance of intracellular recognition mechanisms and demonstrated that signal transducers and activator of transcription 1 (STAT1) signalling activated bacterial phagocytosis and was involved in the induction of abnormal IL-12 production. In IL-10 KO mouse bone marrow-derived (BM) macrophages, Escherichia coli stimulation induced increased IL-12p70 production compared to lipopolysaccharide combined with interferon (IFN)-γ treatment. Significant repression of IL-12 production was achieved by inhibition of phagocytosis with cytochalasin D, and inhibition of de novo protein synthesis with cycloheximide. Induction of IFN regulatory factors-1 and -8, downstream molecules of STAT1 and the key transcription factors for IK-12 transcription, following E. coli stimulation, were mediated by phagocytosis. Interestingly, STAT1 was activated after stimulation with E. coli in IL-10 KO BM macrophages, although IFN-γ could not be detected. These data suggest that molecules other than IFN-γ are involved in hyper-production mechanisms of IL-12 induced by E. coli stimulation. In conclusion, enteric bacteria stimulate excessive IL-12p70 production in IL-10 KO BM macrophages via phagocytosis-dependent signalling.

Fish Kill Incidents and Harmful Algal Blooms in Omani Waters

Red tide, one of the harmful algal blooms (HABs) is a natural ecological phenomenon and often this event is accompanied by severe impacts on coastal resources, local economies, and public health. The occurrence of red tides has become more frequent in Omani waters in recent years. Some of them caused fish kill, damaged fishery resources and mariculture, threatened the marine environment and the osmosis membranes of desalination plants. However, a number of them have been harmless. The most common dinoflagellate Noctiluca scintillans is associated with the red tide events in Omani waters. Toxic species like Karenia selliformis, Prorocentrum arabianum, and Trichodesmium erythraeum have also been reported recently. Although red tides in Oman have been considered a consequence of upwelling in the summer season (May to September), recent phytoplankton outbreaks in Oman are not restricted to summer. Frequent algal blooms have been reported during winter (December to March). HABs may have contributed to hypoxia and/or other negative ecological impacts. 

Reconstruction of historical nutrient levels in Korean and Japanese coastal areas based on dinoflagellate cyst assemblages

Dinoflagellate cysts acquired from sediment cores were analyzed in order to reconstruct historical nutrient levels in Gamak Bay, Korea and Ariake Bay, Japan. Dinoflagellate cyst assemblages in Gamak Bay were characterized by high proportions of heterotrophic cysts such as Brigantedinium spp., Protoperidinium americanum and Polykrikos cysts, which suggested that nutrients levels may have already been high before 1970s, and then increased further to the hypertrophic conditions of the 1990s. In contrast, dinoflagellate cyst assemblages in Ariake Bay were characterized by high relative abundances of Lingulodinium machaerophorum and Spiniferites spp., which suggested that nutrient levels in Ariake Bay had increased gradually since the mid 1960s, and may have been significantly enhanced by the mid 1980s. Dinoflagellate cyst assemblages reflecting environmental changes in the two bays are contrasting, perhaps due to different nutrient enrichment mechanisms. This suggests that the indicators of nutrient levels encoded in dinoflagellate cyst assemblages may exhibit site-specific information.

A randomized trial of personalized peptide vaccine (PPV) plus low-dose estramustine (EMP) versus full-dose EMP in patients with hormone-refractory prostate cancer

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Background: Personalized selection of the right peptides for each patient could be a novel peptide-based immunotherapy for boosting anti-cancer immunity in many patients (pts). This randomized study evaluated the anti-tumor effect and safety of PPV plus a low-dose EMP compared with full dose EMP for patients with hormone-refractory prostate cancer (HRPC). Methods: This was a randomized (1:1), open labeled, cross-over study in pts with HRPC. Pts were randomized to arm A; PPV plus low-dose EMP (280 mg/day) or arm B; full dose EMP (560 mg/day) according to age and PSA levels. In arm A, prevaccination plasma were measured for their IgG levels for each of the 14 or 12 candidate peptides which can induce HLA-A2 or A24-restricted CTL activity against cancer cells followed by biweekly subcutaneous administration of the top four peptides (3mg each) showing the strongest IgG responses. Disease progression (PD) was defined as three consecutive and 125% increase from baseline PSA levels at least two weeks apart or objective PD by RECIST criteria. After PD, pts were treated with the opposite regime. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were overall survival and toxicity. The planned sample size was 80. Results: A total of 54 pts from 4 institutions were enrolled between June 2006 and December 2008. The accural into arms A and B was 27 and 27 pts, respectively. The main pts characteristics are (arm A/B): median age 71/69 years, EOCG performance status 0/1 96%/4% and 100%/0%, HLA A2/A24/A2A24 40%/32%/28% and 54%/27%/19%, median PSA 27/25 ng/ml, and metastatic HRPC 96%/85%. All pts were evaluable for their response at the time of interim analysis. The personalized peptide vaccination was well tolerated with no major adverse effects. Increased levels of IgG responses to the vaccinated peptides were observed in 20 of 23 (87%) patients tested. The median PFS time was 246 days in the arm A group and 85 days in the arm B, respectively. The PFS time in the arm A was statistically longer than that in the arm B (log-rank test: p = 0.0007, hazard ratio: 0.27, 95%CI: 0.12 to 0.615). Conclusions: PPV plus low-dose EMP was associated with improvement in PSA-based PFS compared to full-dose EMP alone.

No significant financial relationships to disclose.