Dermal absorption of amorphous nanosilica particles after topical exposure for three days

The skin penetration and cellular localization of well-dispersed amorphous nanosilica particles (nSPs) with a diameter of 70 nm was analyzed in mice. Our results suggest that after topical exposure for three days the particles penetrate the skin barrier and are transported to the lymph nodes. These findings underscore the need to examine biological effects following dermal exposure to nSPs for the development of safer use of nSPs.

Amorphous nanosilica particles induce ROS generation in Langerhans cells

Generation of total intracellular reactive oxygen species (ROS) was measured in XS52 cells, a Langerhans cell-like line, treated with different sized amorphous silica particles. The results suggested that exposure to amorphous nanosilica particles (nSPs) with a particle size of 70 nm induced a higher level of ROS generation than did exposure to micron-sized amorphous silica particles. This finding means that it is essential to examine the biological effects of ROS generated after exposure to nSPs, which will provide useful information for hazard identification as well as the design of safer nanomaterials.

Twofold spontaneous symmetry breaking in the heavy-fermion superconductor UPt3

The field-orientation dependent thermal conductivity of the heavy-fermion superconductor UPt3 was measured down to very low temperatures and under magnetic fields throughout the distinct superconducting phases: B and C phases. In the C phase, a striking twofold oscillation of the thermal conductivity within the basal plane is resolved reflecting the superconducting gap structure with a line of node along the a axis. Moreover, we find an abrupt vanishing of the oscillation across a transition to the B phase, as a clear indication of a change of gap symmetries. We also identify extra two line nodes below and above the equator in both B and C phases. From these results together with the symmetry consideration, the gap function of UPt3 is determined as a E(1u) representation characterized by a combination of two line nodes at the tropics and point nodes at the poles.

Retrospective analysis of an efficient peripheral blood stem cell collection and the relation between infused cell dose and clinical outcome in patients with malignant lymphoma and multiple myeloma

INTRODUCTION

Etoposide (VP16) is a drug used not only for the treatment of lymphoma but also for the collection of peripheral blood stem cells (PBSCs). We analysed the efficacy and adverse effects of collecting PBSCs and the relation between the infused cell dose and the clinical outcome in lymphoid malignancies.

METHOD

Investigating 30 patients with non-Hodgkin's lymphoma, one patient with Hodgkin's lymphoma, and five patients with multiple myeloma, we compared the effects of several doses of etoposide with those of CHOP or CHOP-like treatments or salvage treatments. We also analysed the relation between the amount of CD34(+) cells collected (above or below 5.0 × 10(6) /kg/day) and prognosis of these patients.

RESULTS

We found the collected cell count to be highest in patients treated with 500 mg/m(2) of VP16 and lowest in those not treated with VP16 (P = 0.0073). A CD34(+) cell count above 100/μL on the collection day indicates that the target amount of CD34(+) cells (4.0 × 10(6) /kg) can be readily obtained and was reached most rapidly by the patients who had received 500 mg/m(2) of VP16 (P = 0.01). The longer duration of neutropenia in those patients (P = 0.000006) resulted in longer antibiotic treatment (P = 0.0052). Both progression-free survival (PFS) and overall survival (OS) were better for the patients who yielded more than 5.0 × 10(6) CD34(+) cells/kg/day (P = 0.087 for PFS and P < 0.033 for OS).

CONCLUSION

We show here that 3 days of VP16 at 500 mg/m(2) was useful for the collection of PBSCs and that patients who yielded more than 5.0 × 10(6) CD34(+) cells/kg/day survived longer than those who yielded less.

Rho GDP-dissociation inhibitor alpha is associated with cancer metastasis in colon and prostate cancer

Since metastasis is one of the most important prognostic factors in colorectal cancer, development of new methods to diagnose and prevent metastasis is highly desirable. However, the molecular mechanisms leading to the metastatic phenotype have not been well elucidated. In this study, a proteomics-based search was carried out for metastasis-related proteins in colorectal cancer by analyzing the differential expression of proteins in primary versus metastasis focus-derived colorectal tumor cells. Protein expression profiles were determined using a tissue microarray (TMA), and the results identified Rho GDP-dissociation inhibitor alpha (Rho GDI) as a metastasis-related protein in colon and prostate cancer patients. Consequently, Rho GDI may be useful as a diagnostic biomarker and/or a therapeutic to prevent colon and prostate cancer metastasis.

High-flow Neonatal Macrocerebral Arteriovenous Fistulas in Hereditary Hemorrhagic Telangiectasia

Although some cases of vein of Galen aneurysmal malformation (VGAM) present initial clinical symptoms such as cardiopulmonary disturbance in the neonatal period, pial arteriovenous fistula is very seldom present as a clinical symptom immediately after birth. A neonatal patient, the first-born to his family, presented with tachypnea postpartum. This baby had a family history of hereditary hemorrhagic telangiectasia. A cerebral MR image revealed multiple macrocerebral arteriovenous fistulas (MCAVFs), resulting in a large partially thrombosed venous pouch within the cerebral cortex. Trans-arterial embolizations of the main two fistulas were performed using N-butyl cyanoacrylate (NBCA) with tantalum powder six months after birth. Post-embolization angiography confirmed the obliteration of the fistulas and magnetic resonance imaging (MRI) revealed thrombosis and reduction in size of the venous component. His tachypnea disappeared completely. There were no neurological complications due to the treatment. The prognosis of multiple MCAVFs mainly depends on the presence of medullar signs and symptoms and a delay before treatment. Pure glue endovascular intervention, as used in our case, is considered to be the first therapeutic choice to decrease the risk of neurological consequences.

Detection of titanium dioxide particles on frozen tissue sections using synchrotron radiation X-ray fluorescence analysis

Recent studies into the in vivo absorption and biological influence of particulate matter, especially nanomaterials (NMs), have raised worldwide concerns over their safety. However, it is often technically difficult to conduct these studies because NMs are too small to be observed by optical microscopy. Here, we attempted to establish a new method to visually detect NMs on tissue samples. Specifically, we have analyzed titanium dioxide particles with a diameter of 5 microm, which are widely used in cosmetics, using frozen tissue sections by synchrotron radiation X-ray fluorescence analysis.

Size-dependent immune-modulating effect of amorphous nanosilica particles

The immune-modulating effect following intradermal injection of various-sized amorphous silica particles was analyzed in terms of induction of ovalbumin-specific CD8+ T cells in vivo. IFN-gamma ELISPOT assays revealed that only nanosilica particles with a diameter of less than 100 nm significantly enhanced CD8+ T cell responses against ovalbumin. These results indicate that the size of nanomaterials is a critical determinant in terms of their safe use.

Hepatotoxicity of silica nanoparticles with a diameter of 100 nm

Nanomaterials have potential toxicity that is not found in micromaterials, and it is therefore essential to understand their biological activity and potential toxicity. We focused on silica nanoparticles, since it was previously reported that the intravenous administration of silica nanoparticles with a diameter of 70 nm (SP70) causes hepatic injury. In the present study, we focused on the effects of the particle diameter of silica. We found that silica nanoparticles caused acute liver toxicity at a diameter of 100 nm, and that liver sinusoidal endothelial cells are directly involved in silica nanoparticle-induced liver injury. These findings suggest that the diameter of nanoparticles has great influence on silica nanoparticle-induced liver injury.