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.

Differences in odor identification among clinical subtypes of Parkinson's disease

OBJECTIVE

Olfactory dysfunction is a non-motor symptom in idiopathic Parkinson's disease (PD). We investigated whether this dysfunction differs among clinical subtypes of PD.

METHODS

Participants comprised of 90 patients with idiopathic PD and without dementia. Olfactory function was evaluated using the odor stick identification test for Japanese, which evaluated the detection of 12 odorants familiar to Japanese participants. Patients were divided into tremor-dominant type (TDT), akinetic-rigid type (ART), and mixed type (MXT) PD subgroups using part III of the Unified Parkinson's Disease Rating Scale.

RESULTS

Fifty-five patients were classified as ART, 21 as MXT, and 14 as TDT. There were no differences in age, sex, or duration of illness among the subtypes. Subjective symptoms of impaired sense of smell were significantly higher (P<0.05) in the ART than in the TDT. Mean odor identification score was 4.3 in the ART, 5.2 in MXT, and 6.6 in TDT. It was significantly lower in the ART than in the TDT (P<0.01).

CONCLUSION

Olfactory dysfunction differed among the clinical subtypes of PD. This suggests that olfactory function might relate to prognosis of patients with PD.

Effect of surface charge on nano-sized silica particles-induced liver injury

Nanomaterials are used frequently in microelectronics, cosmetics and sunscreen, and research for the development of nanomaterial-based drug delivery systems is promising. We previously reported that the intravenous administration of unmodified silica particles with a diameter of 70 nm (SP70) caused hepatic injury. Here, we examined the acute hepatic toxicity of SP70 modified with amino group (SP70-N) or carboxyl group (SP70-C). When administered intravenously into mice, SP70-N and SP70-C dose-dependently increased the serum level of alanine aminotransferase (ALT). However, the toxicity levels of surface charge-modified silica particles were much less weaker than the level of unmodified particles. When SP70 was repeatedly administered at 40 mg/kg twice a week for 4 weeks into mice, the hydroxyproline content of the liver significantly increased. Azan staining of the liver section indicated the extensive fibrosis. To the contrary, the repeated administration of SP70-N or SP70-C at 60 mg/kg twice a week for 4 weeks into mice did not cause the hepatic fibrosis. These findings suggest that the surface charge of nanomaterials could change their toxicity.

Effect of 70-nm silica particles on the toxicity of acetaminophen, tetracycline, trazodone, and 5-aminosalicylic acid in mice

Exposure to nano-sized particles is increasing because they are used in a wide variety of industrial products, cosmetics, and pharmaceuticals. Some animal studies indicate that such nanomaterials may have some toxicity, but their synergistic actions on the adverse effects of drugs are not well understood. In this study, we investigated whether 70-nm silica particles (nSP70), which are widely used in cosmetics and drug delivery, affect the toxicity of a drug for inflammatory bowel disease (5-aminosalicylic acid), an antibiotic drug (tetracycline), an antidepressant drug (trazodone), and an antipyretic drug (acetaminophen) in mice. Co-administration of nSP70 with trazodone did not increase a biochemical marker of liver injury. In contrast, co-administration increased the hepatotoxicity of the other drugs. Co-administration of nSP70 and tetracycline was lethal. These findings indicate that evaluation of synergistic adverse effects is important for the application of nano-sized materials.

Recurrent atrial fibrillation after high-dose methylprednisolone therapy in a girl with lupus-associated hemophagocytic syndrome

Hemophagocytic syndrome (HPS) is a serious complication of systemic lupus erythematosus (SLE). A 15-year-old female with lupus-nephritis developed HPS. Bone marrow study showed florid thrombophagocytosis. There was no associated infection. High-dose methylprednisolone therapy ameliorated HPS. However, atrial fibrillation (Af) repeated after the infusion and required direct-current cardioversion. No underlying diseases were found in the heart and endocrine system. Chest roentgenogram and echocardiography were normal. Electrocardiogram showed slightly prolonged PR interval in sinus rhythm. Af occurred at high circulating levels of interferon-γ and interleukin (IL)-10, but not IL-6, IL-2, tumor necrosis factor-α, C-reactive protein or catecholamines. This is the first observation that high-dose corticosteroid induced Af in a case of lupus-HPS. Af is unusual in SLE children without cardiac disease, while conduction defect occurs associated with lupus-myocarditis. Lupus-HPS may be an aggressive SLE subset with cardiac involvement. High-dose corticosteroid infusion controls lupus activity, but could disclose the cardiac stress in lupus-HPS patients.

Cathodic alkaline treatment of zirconium to give the ability to form calcium phosphate

The cathodic polarization technique to form an alkaline environment on a zirconium (Zr) surface, discussed in the present study, is unique, and gives the ability to form calcium phosphate in a simulated body fluid to Zr; on the other hand, many previous studies have been conducted using immersion in alkaline solutions. In this study, two discrete techniques were investigated. Zr was cathodically polarized in an electrolyte without calcium and phosphate ions, and Zr was cathodically polarized in another electrolyte containing calcium and phosphate ions, Hanks' solution, to directly form a calcium phosphate layer. The surface was characterized using X-ray photoelectron spectroscopy, and the performance of the material was evaluated by immersion in Hanks' solution. As a result, the ability to form calcium phosphate in Hanks' solution was given by cathodic polarization in the Na(2)SO(4) solution containing H(2)O(2). In addition, a cathodic potential under -1.5 V(SCE) is required to form hydroxyapatite directly in Hanks' solution. This research clearly reveals useful surface modification techniques giving the ability to form calcium phosphate in a simulated body fluid by cathodic polarization.

Arsenic trioxide induces down-regulation of gp46 via protein oxidation: proteomics analysis of oxidative modified proteins in As2O3-treated HTLV-1-infected cells

Adult T-cell leukemia (ATL) is a severe chemotherapy-resistant malignancy associated with prolonged infection by the human T cell-lymphotropic virus 1 (HTLV-1) retrovirus. Epidemiology studies strongly indicate that an increase in HTLV-1 virus load is an important factor during the onset of ATL. Therefore, inhibition of the growth/transmission of HTLV-1 infected cells is a promising strategy in preventing the disease. In our previous study, we revealed that arsenic trioxide (As2O3), a drug used to treat acute promyelocytic leukemia (APL), exerts an inhibitory effect on syncytium formation between HTLV-1 infected cells and HeLa cells via suppression of HTLV-1 envelope protein gp46 expression at low concentrations. In this study, we analyze the mechanism of action of As2O3 using a proteomics approach. Our results suggest that down-regulation of gp46 might be related to As2O3-induced oxidation of the 71-kDa heat shock cognate protein (HSC70) and the 78-kDa glucose-regulated protein (BiP/GRP78). We postulate that AS2O3 exerts an inhibitory effect on HTLV-1 virus transmission via down-regulation of gp46-production, which might be caused by oxidative modification of various proteins such as chaperones.

Cytotoxicity of amorphous silica particles against macrophage-like THP-1 cells depends on particle-size and surface properties

Recent studies have indicated that amorphous silica particles (SPs) show cytotoxicity against various types of cells, including macrophages. However, the mechanism of cell death has not been determined, and systematic investigations of the relationship between particle characteristics and cytotoxicity are still quite limited. Here, we compared the cytotoxicity of SPs of various sizes (30-1000 nm) and surface properties against differentiated THP-1 human macrophage-like cells. We found that 300 and 1000 nm SPs showed cytotoxicity against THP-1 cells, whereas 30, 50, and 70 nm SPs did not induce cell death. We demonstrated that 1000 nm SP showed strong cytotoxicity that depended on reactive oxygen species but was independent of caspases. Furthermore, we showed that surface modification of 1000 nm SPs dramatically suppressed their cytotoxicity. Our results suggest that systematic evaluation of the association between particle characteristics and biological effects is necessary for the creation of safe SPs.

Mutant TNF-alpha, mTNF-K90R, is a novel candidate adjuvant for a mucosal vaccine against HIV

The development of a safe and effective mucosal vaccine adjuvant is a crucial step for the development of vaccines against human immunodeficiency virus type-1 (HIV). We have previously reported that a mutant tumor necrosis factor-alpha (TNF-alpha), mTNF-K90R, possessed strong mucosal vaccine adjuvant activities in mice. Here, we evaluated the potential of mTNF-K90R as a mucosal vaccine adjuvant for the induction of systemic and mucosal immune responses against HIV. Nasal immunization of BALB/c mice with 5 microg of an HIV gp120 env protein immunogen together with mTNF-K90R induced higher serum anti-HIV gp120 protein immunoglobulin G (IgG) responses than gp120 alone. Furthermore, mTNF-K90R induced anti-gp120 IgA responses in nasal as well as vaginal washes from immunized mice, although these were not administration sites. Again, responses with mTNF-K90R were higher than with gp120 alone. These results indicate that mTNF-K90R may be applicable as amucosal adjuvant for HIV vaccination to induce both systemic and mucosal immune responses.

Size-dependent cytotoxic effects of amorphous silica nanoparticles on Langerhans cells

Amorphous silica nanoparticles (nSPs), are widely used in medicines, cosmetics and food. However, due to their reduced particle size they are suspected to pose new risks induced by changes in biological reactivity and kinetics, which differ from those of bulk materials. In a previous study, we showed that silica particles with a diameter of 70 nm penetrated the stratum corneum (SC) of mouse skin and were taken up by living cells such as keratinocytes and Langerhans cells. To clarify the relationship between particle size, distribution and cellular response, we have evaluated size-dependent intracellular localization and cytotoxicity of silica particles, using the mouse epidermal Langerhans cell line XS52. On treatment with silica particles of diameters 70, 300, and 1000 nm, cellular uptake and cytotoxicity increased with reduction in particle size. These results suggest that smaller sized silica particles induced greater cytotoxicity against Langerhans cells, which was correlated with the quantity of particle uptake into the cells.