Trapped radical behavior of electron beam irradiated polytetrafluoroethylene fine powder at various temperatures.

Polytetrafluoroethylene (PTFE) fine powder with 93% crystallinity was irradiated by an electron beam (EB) at various temperatures under a nitrogen atmosphere. Trapped free radicals in PTFE were studied using electron spin resonance (ESR) spectroscopy. The observed spectra of the samples exposed to air after irradiation at various temperatures showed asymmetrical signals, which are middle-chain type peroxide macroradicals derived from fluoroalkyl radicals. The radical yields at each irradiation temperature increased with increasing absorbed dose, and eventually saturated. The higher irradiation temperature resulted in higher radical yields when compared at the same exposed dose. Furthermore, the G-value of the radicals (G(R·)) increases with increasing irradiation temperatures corresponding to each relaxation and transition temperature. It is concluded that the chain reaction by the fluorine extraction from the main chain due to the end-chain radical generated via ß-scission after dissociative electron attachment (DEA) is enhanced by the synergistic effect of heat and radiation.

Pentadecafluorooctanoic-acid-free polytetrafluoroethylene and mechanism of PFOA formation by γ-irradiation.

Low-molecular-weight (Mw) polytetrafluoroethylene (PTFE) micropowder is added to wax for use in automotive equipment and printing machines and is produced by radiation-initiated degradation under atmospheric conditions. However, pentadecafluorooctanoic acid (PFOA) is produced as a by-product in concentrations greater than 25 ppb, which is problematic because PFOA does not degrade in the environment. Herein, we clarify the PFOA-formation mechanism and develop a manufacturing process for a novel low-Mw PTFE micropowder that does not contain PFOA (less than 5 ppb). The process uses combined irradiation and heat treatment in an oxygen-free atmosphere. Furthermore, PFOA-free PTFE micropowder can be produced on the 10-kg scale.

Spatially resolved spectral phase interferometry with an isolated attosecond pulse.

We demonstrate spatially resolved supercontinuum spectral phase interferometry with an isolated attosecond pulse (IAP). The measured spatial-spectral interferogram over the broadband region indicates a high degree of IAP coherence in both spatial and spectral domains. In addition, the spectral-delay interferogram shows periodic temporal oscillations over the full IAP continuous spectrum, which indicates high temporal coherence. The supercontinuum spectral phase interferometry with broadband IAP will contribute to exploring spatiotemporal dispersive electronic dynamics through phase-based spectroscopy in the future.

Fabrication of nanobeads from nanocups by controlling scission/crosslinking in organic polymer materials.

The development of several kinds of micro/nanofabrication techniques has resulted in many innovations in the micro/nanodevices that support today's science and technology. With feature miniaturization, the fabrication tools have shifted from light to ionizing radiation. Here, we propose a simple micro/nanofabrication technique for organic materials using a scanning beam (SB) of ionizing radiation. By controlling the scission/crosslinking of the material via three-dimensional energy-deposition distribution of the SB, appropriate solvents can easily peel off only the crosslinked region from the bulk material. The technique was demonstrated using a focused ion beam and a chlorinated organic polymer. The polymer underwent main-chain scission upon irradiation, but it crosslinked after high-dose irradiation. Appropriate solvents could easily peel off only the crosslinked region from the bulk material. The technique, 'nanobead from nanocup', enabled the production of desired structures such as nanowires and nanomembranes. It can be also applied to the micro/nanofabrication of functional materials.

[Outcomes of endoscopic sinus surgery in chronic sinusitis cases complicated/ not complicated by bronchial asthma and eosinophilic infiltration of the sinus mucosa].

BACKGROUND: Intractable sinusitis is, in most cases, complicated by bronchial asthma and severe eosinophilic infiltration of the sinus mucosa. Our aim here was to study the postoperative outcomes of chronic sinusitis complicated/not complicated by bronchial asthma and of cases with eosinophilic sinusitis/non-eosinophilic sinusitis. METHODS: We conducted a prospective analysis of the outcome of 180 patients with or without bronchial asthma and eosinophilic infiltration who underwent endoscopic sinus surgery (ESS) for chronic sinusitis. The patients were divided into four groups by the presence/absence of asthma and presence/absence of eosinophilic infiltration of the sinus mucosa. One surgeon performed the ESS, and all the groups received the same postoperative treatment. RESULTS: The outcomes of ESS were significantly worse in the cases complicated by eosinophilic sinusitis and asthma, especially in relation to the incidence of smell disturbances and the endonasal findings. Patients suffering from chronic sinusitis without asthma showed good improvement following ESS. There was no significant differences in the outcome after ESS between cases of eosinophilic sinusitis and those with non-eosinophilic sinusitis among the patients without asthma. CONCLUSIONS: We contend that eosinophilic sinusitis without asthma may not represent intractable sinusitis. We wish to emphasize that complication by

A clinical study of endoscopic sinus surgery for sinusitis in patients with bronchial asthma.

BACKGROUND: An association between bronchial asthma and sinusitis has long been suspected. Our aim is to study the clinical features of chronic sinusitis associated with bronchial asthma as two manifestations of one airway disease. METHODS: We conducted a prospective analysis of the outcome of 88 patients, with or without bronchial asthma, who underwent endoscopic sinus surgery (ESS) for chronic sinusitis. Patients were divided into two groups by the presence or absence of asthma and were evaluated. One surgeon performed the ESS, and the same postoperative treatment was given to both groups. The postoperative outcomes of symptoms and objective findings related to sinusitis were evaluated numerically, with a maximum score of 2 points for each examination item. Twenty-eight patients with asthma symptoms were assessed before and after surgery, using peak flow (liter/second) and medication scores (according to US Food and Drug Administration) to determine whether bronchial asthma was improved by first-time ESS. RESULTS: The outcomes of ESS were significantly worse in the asthma group, especially the endonasal findings. Patients suffering from chronic sinusitis and bronchial asthma showed improvement following ESS in terms of their asthma symptoms, peak flow and medication score. Patients with a good ESS result tended to have the greatest improvement in their asthma. CONCLUSIONS: We conclude that sinusitis and asthma are closely related to each other, acting as two manifestations of one airway disease. We recommend treating cases of sinusitis complicated by asthma as a single disease of the entire respiratory tract.

Two-photon microscopic analysis of acetylcholine-induced mucus secretion in guinea pig nasal glands.

The spatiotemporal changes in intracellular free Ca(2+) concentration ([Ca(2+)](i)) as well as fluid secretion and exocytosis induced by acetylcholine (ACh) in intact acini of guinea pig nasal glands were investigated by two-photon excitation imaging. Cross-sectional images of acini loaded with the fluorescent Ca(2+) indicator fura-2 revealed that the ACh-evoked increase in [Ca(2+)](i) was immediate and spread from the apical region (the secretory pole) of acinar cells to the basal region. Immersion of acini in a solution containing a fluorescent polar tracer, sulforhodamine B (SRB), revealed that fluid secretion, detected as a rapid disappearance of SRB fluorescence from the extracellular space, occurred exclusively in the luminal region and was accompanied by a reduction in acinar cell volume. Individual exocytic events were also visualized with SRB as the formation of Omega-shaped profiles at the apical membrane. In contrast to the rapidity of fluid secretion, exocytosis of secretory granules occurred with a delay of approximately 70s relative to the increase in [Ca(2+)](i). Exocytic events also occurred deep within the cytoplasm in a sequential manner with the latency of secondary exocytosis being greatly reduced compared with that of primary exocytosis. The delay in sequential compound exocytosis relative to fluid secretion may be important for release of the viscous contents of secretory granules into the nasal cavity.

Stabilization of exocytosis by dynamic F-actin coating of zymogen granules in pancreatic acini.

Reorganization of F-actin in the apical region of mouse pancreatic acinar cells during Ca(2+)-dependent exocytosis of zymogen granules was investigated by two-photon excitation microscopy with intact acini. Granules were rapidly coated with F-actin in response to either agonist stimulation or photolysis of a caged-Ca(2+) compound. Such F-actin coating occurred exclusively at the surface of granules undergoing exocytosis and was prevented either by latrunculin-A, which inhibits actin polymerization, or by Clostridium botulinum exoenzyme C3, which inhibits the small GTPase Rho. Latrunculin-A or exoenzyme C3 also triggered the formation of vacuoles in acinar cells, a characteristic of acute pancreatitis. Stimulation of acini with high concentrations of cholecystokinin, which cause acute pancreatitis in mice, also impaired the F-actin coating of granules and induced vacuole formation. Latrunculin-A reduced the latency to exocytosis but did not affect the total number of exocytic events, suggesting that F-actin slows and further stabilizes exocytosis by facilitating F-actin coating. Rho-dependent F-actin coating of granule membranes thus stabilizes exocytic structures and is necessary for physiological progression of sequetial compound exocytosis in the exocrine pancreas and for prevention of acute pancreatitis.

Chemical chaperone therapy for brain pathology in G(M1)-gangliosidosis.

We synthesized a galactose derivative, N-octyl-4-epi-beta-valienamine (NOEV), for a molecular therapy (chemical chaperone therapy) of a human neurogenetic disease, beta-galactosidosis (GM1-gangliosidosis and Morquio B disease). It is a potent inhibitor of lysosomal beta-galactosidase in vitro. Addition of NOEV in the culture medium restored mutant enzyme activity in cultured human or murine fibroblasts at low intracellular concentrations, resulting in a marked decrease of intracellular substrate storage. Short-term oral administration of NOEV to a model mouse of juvenile GM1-gangliosidosis, expressing a mutant enzyme protein R201C, resulted in significant enhancement of the enzyme activity in the brain and other tissues. Immunohistochemical stain revealed a decrease in the amount of GM1 and GA1 in neuronal cells in the fronto-temporal cerebral cortex and brainstem. However, mass biochemical analysis did not show the substrate reduction observed histochemically in these limited areas in the brain probably because of the brief duration of this investigation. Chemical chaperone therapy may be useful for certain patients with beta-galactosidosis and potentially other lysosomal storage diseases with central nervous system involvement.

Topical FK506 (tacrolimus) therapy for facial erythematous lesions of cutaneous lupus erythematosus and dermatomyositis.

Tacrolimus is a prototype of a class of topical immunosuppressive agents with great potential for the treatment of inflammatory skin diseases. Topical tacrolimus therapy was applied to facial skin lesions in 11 cases of cutaneous lupus erythematosus (LE) and dermatomyositis. Of the 11 patients, 6 (3 systemic LE, one discoid LE and 2 dermatomyositis) showed a marked regression of their skin lesions after tacrolimus therapy, but 4 patients (3 discoid LE and one dermatomyositis) were resistant to the therapy. A good response was observed for facial erythematous lesions with edematous or telangiectatic changes in systemic LE and dermatomyositis. In discoid LE with typical discoid lesions, tacrolimus brought no improvement. Topical tacrolimus will become a new tool for managing the skin lesions of collagen diseases.