Inhibitory mechanisms of glycoprotein fraction derived from Miscanthus sinensis for the immediate phase response of an IgE-mediated cutaneous reaction

OBJECTIVE: To determine the risk factors for colonization or infection with methicillin-resistant Staphylococcus aureus in human immunodeficiency virus (HIV)-infected patients. DESIGN: Retrospective matched-pair case-control study. SETTING: Continuity clinic and inpatient HIV service of a university medical center. POPULATION: Patients with HIV infection from the general population of eastern and coastal Texas and from the Texas Department of Criminal Justice. DATA COLLECTION: Patient charts and the AIDS Care and Clinical Research Program Database were reviewed for the following: age, race, number of admissions, total hospital days, presence of a central venous catheter, serum albumin, total white blood cell count and absolute neutrophil count, invasive or surgical procedures, any cultures positive for S. aureus, and a history of opportunistic illnesses, diabetes, or dermatologic diagnoses. Data also were collected on the administration of antibiotics, antiretroviral therapy, steroids, cancer chemotherapy, and subcutaneous medications. RESULTS: In the univariate analysis, the presence of a central venous catheter, an underlying dermatologic disease, lower serum albumin, prior steroid therapy, and prior antibiotic therapy, particularly antistaphylococcal therapy or multiple courses of antibiotics, were associated with increased risk for colonization or infection with methicillin-resistant S. aureus. Multivariate analysis yielded a model that included presence of a central venous catheter, underlying dermatologic disease, broad-spectrum antibiotic exposure, and number of hospital days as independent risk factors for colonization or infection with methicillin-resistant S. aureus. CONCLUSIONS: In our HIV-infected patient population, prior hospitalization, exposure to broad-spectrum antibiotics, presence of a central venous catheter, and dermatologic disease were risk factors for acquisition of methicillin-resistant S. aureus.     

Preparation and properties of ester or cyano group substituted ring-opening polymers and their hydrogenated derivatives

Ester or cyano substituted tetracyclo [4.4.0.1^2,5.1^7,10]dodec-3-enes (1) were synthesized and their metathesis ring-opening polymerization was examined. The tungsten-based ternary catalyst system polymerized them very well. The polymers showed high glass transition temperatures (T_g) and no evidence of crystallization (e.g., the T_g of the polymer derived from 8-methyl-8-methoxycarbonyl substituted monomer (1a) was 207°C, and colorless transparent films could be casted from the solution of the polymer). The stability of these high T_g polymers were too unstable, so practical thermal molding methods could not be applied to them. The hydrogenation of these polymers with a palladium catalyst decreased T_g and greatly increased thermal stability. The physical and thermal properties of the hydrogenated polymers were thoroughly investigated. Monomer 1 was successfully copolymerized with other cyclic olefins. The resultant copolymers were hydrogenated, giving thermally stable polymers. In all cases examined in this study, a decrease of T_g by hydrogenation was about 35°C, regardless of the monomer structure. These results indicate that the main-chain mobility is the major contribution to the decrease of T_g. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 367–375, 1997     

Effect of Surface Treatment on the Selective Photocatalytic Oxidation of Benzyl Alcohol into Benzaldehyde by O2 on TiO2 Under Visible Light

The photocatalytic oxidation of benzyl alcohol into benzaldehyde proceeded with high conversion and selectivity on a TiO₂ photocatalyst by O₂ under visible light irradiation. Surface complex formed by the interaction of benzyl alcohol with the Ti sites and/or surface OH groups of TiO₂ play an important role in the absorption of visible light and unique selective photocatalytic reaction.     

Effect of Support Materials on the Selective Methanation of CO over Ru Catalysts

Selective methanation of CO in the reformate gas (CO/CO₂/H₂/H₂O = 0.175/17.9/70.9/11.1) proceeded over Ru catalysts supported on metal oxides and zeolites. CO was selectively methanated at wide temperature ranges (200–275 °C) over Ru/γ-Al₂O₃, Ru/TiO₂ Ru/H-Y and Ru/H-beta catalysts. Higher Ru contents in Ru/γ-Al₂O₃ improved the selective CO methanation rate.     

Characterization of Silicon Carbide–Silicon Nitride Composite Ultrafine Particles Synthesized Using a CO2 Laser by Silicon-29 Magic Angle Spinning NMR and ESR

The structure of silicon carbide–silicon nitride (SiC–Si₃N₄) composite particles synthesized using a CO₂ laser was studied by magic angle spinning nuclear magnetic resonance (MAS-NMR) and electron spin resonance (ESR). The structure around Si atoms changed by introducing N. C atoms around Si were substituted by N atoms, and N-rich configurations around Si atoms increased stepwise as the N content increased. The low N content composite particles consisted of mainly SiC phase containing dissolved N. N atoms were partly present in β-SiC microcrystal and partly in the grain boundary layer in the particle. N atoms were tetrahedrally surrounded by four Si atoms in β-SiC microcrystal and were trivalent state bonded to three Si atoms in the grain boundary layer. The high N content particles consisted of SiC, Si₃N₄, and amorphous phases, whose amount depended on N content.     

Transient analysis of the release and reduction of NOx using a Pt/Ba/Al2O3 catalyst

The release and reduction of NO_x in a NO_x storage-reduction (NSR) catalyst were studied with a transient reaction analysis in the millisecond range, which was made possible by the combination of pulsed injection of gases and time resolved time-of-flight mass spectrometry. After an O₂ pulse and a subsequent NO pulse were injected into a pellet of the Pt/Ba/Al₂O₃ catalyst, the time profiles of several gas products, NO, N₂, NH₃ and H₂O, were obtained as a result of the release and reduction of NO_x caused by H₂ injection. Comparing the time profiles in another analysis, which were obtained using a model catalyst consisting of a flat 5 nmPt/Ba(NO₃)₂/cordierite plate, the release and reduction of NO_x on Pt/Ba/Al₂O₃ catalyst that stored NO_x took the following two steps; in the first step NO molecules were released from Ba and in the second step the released NO was reduced into N₂ by H₂ pulse injection. When this H₂ pulse was injected in a large amount, NO was reduced to NH₃ instead of N₂.

A only small amount of H₂O was detected because of the strong affinity for alumina support. We can analyze the NO_x regeneration process to separate two steps of the NO_x release and reduction by a detailed analysis of the time profiles using a two-step reaction model. From the result of the analysis, it is found that the rate constant for NO_x release increased as temperature increase.     

Hepatoblastoma in an adult associated with c-met proto-oncogene imbalance

A rare case of hepatoblastoma in a 61-year-old Japanese housewife is described. This liver tumor mainly consisted of two tissue components: embryonal hepatocytes and primitive mesenchymal tissue. Fetal hepatocytes with alpha-fetoprotein production, gland formation, cartilage and osteoid were also found in a small portion. Molecular analysis by slot blot method revealed increased copy numbers of c-met and K-sam proto-oncogenes and cyclin D1 genes. These findings suggest that alterations of these oncogenes might play a role in the development of adult hepatoblastoma.     

Kinetics of HbA1c, glycated albumin, and fructosamine and analysis of their weight functions against preceding plasma glucose level

OBJECTIVE: To examine the kinetics of HbA1c, glycated albumin (GA), and fructosamine (FA) levels in response to plasma glucose change and their relationship with the preceding plasma glucose level. RESEARCH DESIGN AND METHODS: The time courses of HbA1c, GA, and FA after acute glycemic normalization were observed in nine patients with newly diagnosed non-insulin-dependent diabetes mellitus and compared with theoretical ones. Their weight functions against preceding plasma glucose level were analyzed assuming a stepwise plasma glucose change and compared with the theoretical prediction. RESULTS: The fasting plasma glucose level was acutely normalized after admission with a half-time of 6.3 +/- 2.4 days (mean +/- SD). The HbA1c level decreased linearly during the initial 2 months with a half-time of 34.6 +/- 10.1 days, followed by a gradual decrease thereafter. GA and FA levels decreased very rapidly during the initial 2-3 weeks with half-times of 17.1 +/- 2.8 and 12.2 +/- 4.8 days, respectively, followed by a gradual decrease thereafter. The time courses of HbA1c, GA, and FA agreed well with theoretically estimated decay curves. Experimental values of weight functions against the preceding plasma glucose level agreed well with the theoretical prediction. The weight functions for glycated proteins had maximum values on the days just before the measurement of glycated proteins and gradually decreased with an increasing time interval. The lengths of the periods over which the weight functions for HbA1c, GA, and FA extend back were estimated to be roughly 100, 40, and 30 days, respectively. CONCLUSIONS: The levels of HbA1c, GA, and FA do not reflect the simple mean but reflect the weighted mean of the preceding plasma glucose level over a considerably longer period than was previously speculated.     

Viral interleukin 10 (IL-10), the human herpes virus 4 cellular IL-10 homologue, induces local anergy to allogeneic and syngeneic tumors

After the cloning of murine cytokine synthesis inhibitory factor, it was recognized that a homologous open reading frame was encoded within the Epstein-Barr virus (human herpes virus 4). This viral protein has now been termed viral interleukin 10 (vIL-10) to reflect its protein sequence homology to "cellular" IL-10 (cIL-10, either murine or human IL-10). It is now widely accepted that vIL-10 shares many functions with cIL-10, principally, the ability to enhance survival of newly infected B cells and to diminish the production of IFN-gamma and IL-2 during ongoing immune reactions. The immunomodulatory effect of locally secreted vIL-10 and murine IL-10 (mIL-10) was examined in tumor models using CL8-1 (a BL6 melanoma cell line transfected with the H-2Kb class I gene) in syngeneic animals. Although parental BL6 tumor cells grow in immunocompetent syngeneic hosts, CL8-1 are rejected. To achieve local secretion of vIL-10, we generated vIL-10 retroviral vectors. While nontransduced CL8-1 cells (1 x 10(4)) failed to grow when injected intradermally in C57BL/6 mice, CL8-1 cells (1 x 10(4)) transduced with vIL-10 formed palpable tumors and eventually killed 80% of injected animals. Suppression of tumor rejection was also noted when CL8-1 tumors with or without vIL-10 transfection were admixed with syngeneic vIL-10-transfected fibroblasts and inoculated. Since the in vitro proliferation of the tumor was not altered after transduction with the vIL-10 gene and injection of vIL-10-transduced CL8-1 does not affect the rejection of nontransduced CL8-1 inoculated at a distant site, local vIL-10 secretion appears to suppress the process of immune rejection of the target cells in a dose-dependent manner. Similar results were observed for the H-2b MCA105 sarcoma tumor model in allogeneic BALB/c mice (H-2d). Although all animals that received nontransfected MCA105 rapidly rejected these tumors, MCA105 sarcomas transfected with vIL-10 remained palpable for up to 37 d. The local immunosuppressive effect of gene-delivered vIL-10 could be neutralized by anti-human IL-10 monoclonal antibody or could be reversed by the systemic administration of IL-2 or IL-12. In marked contrast, mIL-10 transfection of CL8-1 significantly suppressed tumor growth and frequently led to the rejection of tumor. Similar results were obtained for the murine tumor cell lines MCA102.(ABSTRACT TRUNCATED AT 400 WORDS)     

Influences of debonding rate and temperature on tack properties and peel behavior of polyacrylic block copolymer/tackifier system

The influences of debonding rate and temperature on the peel behavior of polyacrylic block copolymer/tackifier system were investigated. Poly(methyl methacrylate)-block-poly(n-butyl acrylate)-block-poly(methyl methacrylate) triblock copolymer (MAM) with hard block contents of 23 (MAM-23) and 16 wt.% (MAM-16) and a 1/1 blend with a diblock copolymer (MA) consisting of the same components (MAM-23/MA, total hard block content of 15 wt.%) were used as the base polymer. A special rosin ester was used as a tackifier at various contents in the block copolymer/tackifier system. The peeling process at the probe/adhesive interface during probe tack testing was observed using a high-speed microscope at 23 °C with debonding rate of 10 mm/s. Three different peeling mechanisms were observed. Type A, where peeling progressed linearly from the edge to the center of the probe without cavitation (MAM-23). Type B, where peeling progressed linearly from the edge to the center of the probe with cavitation (MAM-16). Type C, where cavitation occurred over the entire adhesive layer, and peeling initiation was delayed (MAM-23/MA). The peel behavior of MAM-23 changed from Type A to Type B with a decrease of the debonding rate (1 mm/s) or increase of the temperature (40 °C). In contrast, there was no change for MAM-16 and MAM-23/MA. Cavity formation in an adhesive layer restrains peeling; therefore, it is desirable for improvement of the adhesion strength. The tack properties increased with the tackifier content, and the formation of cavitation was less than that for the systems without the tackifier.