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Provides information on a study which investigated the third-order nonlinear optical properties of 4-docosylamino-4-nitroazobenzene Langmuir-Blodgett films. Methods; Results; Conclusion.

Introduction: The ability to predict the prognosis of patients with pneumonia is critical, especially when making decisions regarding treatment regimens and sites of care. However, prognostic guidelines for healthcare-associated pneumonia (HCAP) have yet to be established. I-ROAD is the prognostic guideline of the Japanese Respiratory Society for hospital-acquired pneumonia (HAP). This study compared available prognostic guidelines to determine the usefulness of I-ROAD as a prognostic tool for patients with HCAP.Methods: We conducted a retrospective review of all patients with pneumonia admitted to Kameda Medical Center, Japan, from January 2006 to September 2009. Patients were categorised into two groups, namely those with community acquired pneumonia (CAP) and those with HCAP. We compared the baseline characteristics, laboratory findings, identified pathogens, antibiotic regimens, clinical outcomes, pneumonic severity and prognostic accuracy of each guideline between the two patient groups. The severity of each disease was assessed on admission using the A-DROP, CURB-65, PSI and I-ROAD guidelines.Results: Of the 302 patients evaluated, 228 (75.5%) were diagnosed with CAP and 74 (24.5%) with HCAP. Patients with HCAP were older and had a higher performance status than patients with CAP. The mortality rate in the CAP group tended to rise with increasing severity scores of prognostic guidelines. Although the severity scores of all prognostic guidelines could predict 30-day mortality in patients with CAP, I-ROAD exhibited a higher discriminatory power for patients with HCAP based on analysis of receiver-operating characteristic curves.Conclusion: I-ROAD could be more accurate than other prognostic guidelines for evaluating the severity of HCAP. [ABSTRACT FROM AUTHOR]

Germline mutations in the RET tyrosine kinase gene are responsible for the development of multiple endocrine neoplasia 2A and 2B (MEN2A and MEN2B). However, knowledge of the fundamental principles that determine the mutant RET-mediated signaling remains elusive. Here, we report increased expression of mitogen-activated protein kinase phosphatase-2 (MKP-2) in carcinomas developed in transgenic mice carrying RET with the MEN2A mutation (RET-MEN2A). The expression of MKP-2 was not only induced by RET-MEN2A or RET-MEN2B mutant proteins but also by the activation of endogenous RET by its ligand, glial cell line-derived neurotrophic factor (GDNF). MKP-2 expression was also evident in the MKK-f cell line, which was established from a mammary tumor developed in a RET-MEN2A transgenic mouse. Inhibition of MKP-2 attenuated the in vitro and in vivo proliferation of MKK-f cells, which was mediated by the suppression of cyclin B1 expression. Furthermore, we found that MKP-2 is highly expressed in medullary thyroid carcinomas derived from MEN2A patients. These findings suggest that the increased expression of MKP-2 may play a crucial role in oncogenic signaling downstream of mutant RET, leading to deregulation of cell cycle.Oncogene (2008) 27, 5684–5695; doi:10.1038/onc.2008.182; published online 9 June 2008 [ABSTRACT FROM AUTHOR]

The formation of single-wall carbon nanotubes (SWNTs) by using laser vaporization technique in different ambient gas atmosphere was investigated. SWNTs were prepared with Rh/Pd (1.2/1.2 atom%)-carbon composite rod in Ar and nitrogen gas atmosphere, respectively. Raman spectra of raw carbon materials including SWNTs and photoluminescence mapping of dispersed SWNTs in a surfactant solution demonstrate that the diameter distribution of SWNTs prepared in Ar atmosphere is narrower than those obtained by using CVD technique (e.g. HiPco nanotube), even when the ambient temperature is as high as 1150 ○C. It was also found that nitrogen atmosphere gives wider diameter distribution of SWNTs than that obtained with Ar atmosphere. Furthermore, the relative yield of fullerenes (obtained as byproducts) is investigated by using HPLC (high-performance liquid chromatography) technique. It was found that the relative yield of higher fullerenes becomes lower, when nitrogen is used as an ambient gas atmosphere. Based on these experimental findings, a plausible formation mechanism of SWNTs is discussed. [ABSTRACT FROM AUTHOR]

Summary Lipid A is the bioactive centre of lipopolysaccharide (LPS), and its properties exhibit various endotoxic and biological effects toward host cells. We examined whether Toll-like receptors (TLRs) are mediated by the signals from various synthetic acylated derivatives of d-glucosamine monophosphate. All test synthetic monosaccharide lipid A analogues similar to acylated β-(1-6)-d-glucosamine disaccharide bisphosphates, such as Escherichia coli -type lipid A (compound 506) and its precursor (compound 406), clearly induced nuclear factor (NF)-κB activation in Ba/F3 cells expressing murine TLR4 and its accessory protein MD-2 (Ba/mTLR4/mMD-2), but no induction was found in those expressing murine TLR2 (Ba/mTLR2). Compound 411, the non-reducing sugar moiety of compound 506, exhibited interleukin-8 (IL-8) and tumour necrosis factor-α (TNF-α)-producing activities in human peripheral blood mononuclear cells (PBMC), whereas compound 401, the reducing moiety of compounds 506 and 406, and Gifu lipid A-46 (GLA-46), the non-reducing moiety of compound 406, induced no production of IL-8 and TNF-α, which was similar to the findings for compound 406. Among the synthetic triacylated monosaccharide lipid A analogues, some compounds with three tetradecanoyl (C[sub 14] ) groups or that included a dodecanoyl (C[sub 12] ) group were more active toward murine and human cells than were other analogues with a decanoyl (C[sub 10] ) or hexadecanoyl (C[sub 16] ) group. Furthermore, IL-8 production in PBMC stimulated with the active monosaccharide lipid A analogues as well as compound 506 was clearly inhibited by the monoclonal antibody to human TLR4. These findings suggest that monosaccharide lipid A analogues similar to disaccharide lipid As are capable of activating both murine and human cells through TLR4. [ABSTRACT FROM AUTHOR]

Antisense DNA for an ozone-inducible 1-aminocyclopropane-1-carboxylate (ACC) synthase (EC 4.4.1.14; LEACS6) from tomato, under the control of the cauliflower mosaic virus 35S promoter, was introduced into tobacco to generate transgenic plants. Lower rates of ozone-induced ethylene production were observed in three of seven transgenic plants than in the wild-type plants. Ozone-induced visible damage was attenuated in these three lines, and the extent of damage was positively related to the level of ozone-induced ethylene production. In the most ozoneresistant line, ozone-induced accumulation of ACC and levels of transcripts for ozone-inducible endogenous ACC synthases were suppressed compared with those in wildtype plants, demonstrating that ozone-inducible ACC synthases have a key role in the expression of leaf damage by ozone exposure. No significant differences in growth and morphology were observed between transgenic and wildtype plants. Stomatal conductance of transgenic plants during ozone exposure was higher than that of wild-type plants. These findings indicate that the introduction of antisense DNA for an ozone-inducible ACC synthase can improve the ozone tolerance of plants without reducing their gas absorption and productivity. [ABSTRACT FROM AUTHOR]

The formation of colloidal silver in the presence of a nonionic surfactant, Surfynol 465, was studied at various temperatures. By simply mixing equal volumes of AgClO aq. (1-10 mmol kg) and Surfynol 465 aq., the colloidal silver was formed. The colloidal solution had well over ten times the amount of fine silver particles in the solution formed by the ordinary methods. The first factor to form the colloidal silver without aggregation was the molar ratio of Surfynol 465 to AgClO, and the optimum ratio increased with increasing the concentration of AgClO or the temperature. In the fraction of colloidal silver collected through the gel filtration, Surfynol 465 was also found in the micellar state. From these results, it was suggested that Surfynol 465 was a protecting agent of colloidal silver as well as a reducing agent of AgClO in the similar manner to the case of colloidal gold. [ABSTRACT FROM AUTHOR]

Biological and biochemical effects of multiple endocrine neoplasia type 2A (MEN-2A), type 2B (MEN-2B) and familial medullary thyroid carcinoma (FMTC) mutations on Ret function were investigated by transfection of NIH 3T3 cells. All mutations examined conferred transforming activity on Ret at variable levels. Cysteine mutations detected in MEN-2A and FMTC induced disulphide-linked homodimers of Ret on the cell surface, leading to activation of its intrinsic tyrosine kinase. Of these cysteine-mutated proteins, Ret with a codon 634 mutation had the highest transforming activity. The activity of Ret with a codon 609, 611, 618 or 620 mutation was approximately three- to five-fold lower than that of Ret with a codon 634 mutation. The first four mutations impaired the Ret cell surface expression or its correct maturation, resulting in the low transforming activity. On the other hand, the MEN-2B mutation appeared to activate Ret by an intramolecular mechanism without dimerization. In addition, we investigated the role of tyrosines present in the intracellular domain for the transforming activity of the mutant Ret proteins. As a result, we found that tyrosine 905 is essential for the transforming activity of the MEN-2A-Ret mutant protein whereas tyrosines 864 and 952 are critical for that of the MEN-2B-Ret mutant protein. Moreover, it turned out that tyrosine 1062 regulates the activity of both MEN-2A-Ret and MEN-2B-Ret and represents a binding site for the Shc adaptor protein. [ABSTRACT FROM AUTHOR]

Demonstrates the preparation of the Langmuir-Blodgett (LB) films of n-docosyl-2-methyl-4-nitroaniline (DCMNA). Observation of the optical second harmonic generation from the LB multilayers of DCMNA; Polarization of the second harmonic signal parallel to the dipping direction; Derivation of the maximum second harmonic intensity.

A letter to the editor is presented commenting on the case history of a 68-year-old female with small-cell lung cancer with epidermal growth factor receptor mutation.

The substituent effect on photochemical hole burning (PHB) for tetraphenylporphine was studied and the PHB efficiency was related to the electron donating and/or withdrawing properties of the substituents of the phenyl ring. The Hammett-sigma constants of the substituents were related to the efficiency of the photochemical hole burning reaction. Compounds with a low Hammett-sigma constant such as tetra-(4-methoxyphenyl)porphine had a higher PHB reaction efficiency than derivatives with a higher value such as tetraphenylporphine. We have also demonstrated multiple photochemical hole burning using this high efficiency compound tetra-(4-methoxyphenyl)porphine as a guest material. [ABSTRACT FROM AUTHOR]

We carried out 3D magnetohydrodynamic simulations of a subcluster moving in turbulent ICM by including anisotropic heat conduction. Since magnetic fields stretched along the subcluster surface suppress the heat conduction across the front, cold fronts are formed and sustained. [ABSTRACT FROM PUBLISHER]

A condition to achieve a mass separation of an ion beam at a given energy by means of applying a transverse radio frequency (rf) electric field was derived. Effectiveness of the scheme was examined with a He ion beam of energy below 2 kV. An array of four-stage electrodes produced distributed 13.56 MHz rf field to realize a function of a velocity filter. When the extraction voltage of the beam was adjusted to yield a velocity predicted from the theory, the beam current showed transmission as large as 80% through the array of electrodes. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]