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Research describing luminescence in alumina and alumina films prepared by the aqueous sol-gel method is presented. In particular photoelectron trap centers are investigated.

The aqueous sol-gel technique was used to prepare transparent alumina and rare earth ion (Er3+ and Eu3+) doped alumina films.

Cloned mouse mast cells resemble, by ultrastructure, immature mast cells observed in vivo. These mast cell clones can be grown in the absence of any other cells, facilitating direct investigations of their biochemistry and function. We find that cloned mast cells express plasma membrane receptors (Fc epsilon R) that bind mouse IgE with an equilibrium constant (KA) similar to that of normal mouse peritoneal mast cells. In addition, cloned mast cells do not display detectable la antigens and cannot enhance lg secretion when added to lymphocyte cultures or mediate natural killer lysis. In the presence of 1 mM sodium butyrate, cloned mast cells stop dividing and acquire abundant electron-dense cytoplasmic granules similar to those of mature mast cells. Their histamine content increases concomitant with cytoplasmic granule maturation and may exceed that of untreated mast cells by 50-fold. Unlike peritoneal mast cells, cloned mast cells incorporate 35SO4 into chondroitin sulfates rather than heparin. These findings demonstrate that, unlike fully differentiated mouse peritoneal mast cells, cloned immature mouse mast cells contain no heparin and low levels of histamine. In addition, they establish that high-affinity Fc epsilon R are expressed early in mast cell maturation, well before completion of cytoplasmic granule synthesis and mediator storage.

Transparent alumina and rare earth ion (Er[sup 3+] and Eu[sup 3+]) highly doped alumina films (15 mol %) were prepared by the aqueous sol-gel method, in order to examine the effects of various preparation conditions on the structure and optical properties of doped films. The results showed that when the gel was heat treated, it lost free and bound water and was converted into the oxide by way of a series of intermediate phases although the oxide as a whole remained structureless. The thermogravimetric analysis curve showed a marked weight loss in the temperature range of 100-500 °C and the slow loss continuing at higher temperature of 800 °C. High doping may reflect noncrystalline structure of alumina. The fluorescence of Eu[sup 3+] sensitive of microstructure increased especially corresponding to this weight loss with treatment. The Ω[sub 2] indicative of the asymmetric environment of Er[sup 3+] showed a similar increase. Concentration quenching for doped films treated at 800 °C was not significant in this concentration range. Lifetimes increased with increasing treatment temperature, similar to above increase. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A high-pressure and high-temperature (HPHT) water microflow chemical process was utilized for the synthesis of benzazole derivatives. The current approach enables the extremely rapid production of various 2-arylbenzazoles including benzimidazoles, benzoxazoles, and benzthiazole in excellent yields. [ABSTRACT FROM AUTHOR]

The control of luminescence intensity from rare earth ion(Eu 3+ , Tu 3+ )-doped polyimide(PI)nanoparticle film by UV-irradiation and thermal treatment is reported. In the system, it was observed that luminescence intensity assigned to rare earth ion increased with increase of UV-irradiation time, whereas the intensity decreased with elevation of thermal treatment temperature. It was estimated that the mechanism of the above phenomena is based on a reversible change in an energy transfer probability from PI to rare earth ion by the UV-irradiation and the thermal treatment. [ABSTRACT FROM AUTHOR]

A new strain-concentration factor (SNCF) has been defined for plane-strain notched rectangular bars under pure bending. The nominal strain for this new SNCF is obtained from an assumed linear distribution of the longitudinal strain on the net section. This nominal strain is defined under the triaxial stress state at the net section. The new SNCF provides reasonable values for the non-linear distributions of the longitudinal strain, while the conventional SNCF provides unreasonable values. The new SNCF increases from its elastic value to a peak value with plastic deformation. On further deformation it gradually decreases and then increases uptothe value at the general yielding. The relation between the new SNCF and M/M[sub Y], the ratio of the applied bending moment to the bending moment at yielding at the notch root, is independent of the stress-strain curve up to general yielding. [ABSTRACT FROM AUTHOR]

The thick alumina films (0.2-0.5 µm) were prepared on quartz glass and nickel substrates by a dipping method using an alumina sol derived from an aqueous AICI3 solution. The hardness of this coating was compared to those of similarly coated substrates that had been heat-treated at various temperatures. The hardness of the alumina coating increased with increasing heat-treatment temperature. This sol gave crack-free and well-coated substrates that could be heat-treated to temperatures up to 800°C. This may have been due to the formation of an amorphous mixed oxide interface layer between the alumina films and the substrates. At temperatures higher than 900°C, problems with the coating started to appear because the oxide layer formed into a-alumina accompanying evolution of stress in the interface. [ABSTRACT FROM AUTHOR]

Human foetal liver cells are an enriched source of mast cell progenitors that complete their differentiation and mature in response to stem cell factor, the ligand for Kit, in liquid culture. These mast cells are Kit+, metachromatic with toluidine blue+, tryptase+, histamine+ and show ultrastructure features of mast cells. Using a panel of monoclonal antibodies (mAb) against different cell-surface antigens (33 mAb were used), the cell-surface phenotype of human stem cell factordependent foetal liver-derived mast cells was examined by flow cytometry. Consistent with previous reports on tissue-derived mast cells, those derived from foetal liver in vitro expressed HLA class I, CD9, CD29, CD33, CD43, CD45 and Kit. Unlike mast cells dispersed from tissue, a high expression of CD13 was found. Also, these in vitro-derived mast cells express little, if any, high-affinity IgE receptor. However, small amounts of mRNA for the α-chain in foetal liver-derived mast cells compared to KU812 cells (a human basophil-like cell line) could be detected by Northern blotting. Full expression of FcεRI may require additional growth factor(s). [ABSTRACT FROM AUTHOR]

Cocultures of dispersed human fetal liver cells with murine Swiss 3T3 fibroblasts resulted in the development of human mast cells after 1 to 4 weeks of culture. Mast cells were detected by immunohistochemistry using a murine monoclonal anti-tryptase antibody, before metachromasia appeared with toluidine blue. When subjected to double immunohistochemistry using murine monoclonal anti-chymase and anti-tryptase antibodies, 94% ± 10% (SD) of the mast cells seen at day 30 of culture were of the MCT type. These results contrast with those obtained with human mast cells derived from cord blood mononuclear cells cocultured with murine 3T3 fibroblasts which are comprised of substantially greater numbers of MCTC cells, averaging 48% ±31 % (SD) at day 30 of culture. Mast cells developed in vitro from fetal liver cells or cord blood mononuclear cells contained similar amounts (± SD) of histamine (09 ± 0·5 pg/cell and 1·1 ± 1 pg/cell, respectively) and tryptase (1·7± 0·4 pg/cell and 1·9± 1· pg/cell, respectively) on day 30 of culture. Fetal-liver-derived mast cells from a 30-day-old culture were identified by immunoelectron microscopy using gold-labelled anti-tryptase antibody. Typically, these mast cells appeared immature as they had large nuclear to cytoplasmic ratio and a small number of ill-formed cytoplasmic granules. For both fetal-liver- and cord-blood-derived mast cells, there was no evidence of conversion of the MCT type into the MCTC type provided by this study. These results suggest that commitment to develop as an MCT or MCTC type of mast cell may have occurred in mast cell precursors present in fetal liver and cord blood mononuclear cells, prior to granulation. [ABSTRACT FROM AUTHOR]

Recently, particular attention has been paid to a unique subpopulation of mast cells located in the intestinal mucosa of rodents and man (Befus et al., 1982a, b; Strobel, Busuttil & Ferguson, 1983; Ruitenberg et. al., 1982). These cells, presently referred to as mucosal mast cells (MMC), are morphologically, histochemically and functionally distinct from the more extensively studied connective tissue mast cells (Befus et al. 1982b; Pearce et. al, 1982). Our ability to characterize the MMC more fully has been markedly enhanced by the development of techniques to enrich populations of this cell to purities of over 60% (mean 65.6± 5.2%) using density centrifugation over discontinuous Percoll gradients. In this communication, we report the results of our studies to determine the number and affinity characteristics of igG Fc (Fc∊) receptors on enriched MMC isolated from the intestine of rats with parasite-induced mast cell hyperplasia. [ABSTRACT FROM AUTHOR]

Receptors for IgE of rat basophilic leukaemia (RBL) cells, maintained in different laboratories were isolated by means of various anti-receptor antisera, and characterized by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis. Most antisera were shown to react with a receptor designated H and which, as shown previously, could be isolated by IgE-Sepharose but not by a combination of IgE and anti-IgE. Only two highly purified anti-receptor antibody preparations, which had been purified by adsorption to and elution from rat basophilic leukaemia cells, reacted primarily with a second kind of receptor molecule which had previously been designated R. Some indirect evidence was obtained which suggests that H is a highly immunogenic molecule. It was confirmed that the apparent molecular weight of H-like molecules varied on different RBL cell lines. [ABSTRACT FROM AUTHOR]

Receptors for IgE of rat basophilic leukaemia (RBL) cells, maintained in different laboratories were isolated by means of IgE-Sepharose or IgE and anti-IgE, and characterized by SDS-polyacrylamide gel electrophoresis. All cell lines were found to be associated with a receptor molecule (R) which could be isolated either with IgE-Sepharose or IgE and anti-IgE and a second receptor (H) which could only be isolated with the aid of IgE-Sepharose. The relative amounts of these two molecules, as isolated from surface iodinated cells, varied from one RBL cell line to the other and their apparent molecular weights were not identical on all cell lines. Since comparisons were made on the same gel using receptors isolated from cells labelled with different isotopes of iodine, differences in molecular weight must be considered as being intrinsic and not due to methodological variations. These results provide an explanation why differences were observed among receptors for IgE as characterized in various laboratories. In spite of the fact that the various RBL cell lines originated from the same chemically-induced tumour they have, over the years, undergone changes which are reflected in the receptors for IgE. [ABSTRACT FROM AUTHOR]

Fibroblasts have been implicated as culture-competent cells for the mast cell lineage in several species. In man. fibroblast monolayers sustain the ultrastructural phenotype and function of isolated human lung mast cells and permit the differentiation and full maturation of human mast cells from their agranular precursors in cord blood cells, We examined whether development and maturation of the mast cell lineage in man can be achieved by a supply of the soluble products present in fibroblast culture supernatants. Suspension cultures of cord blood cells were supplemented with culture supernatants derived from two different murine fibroblast lines; controls were not supplemented. The cultures were sampled for light and electron microscopy at 6. 7 and 8 weeks. Human mast cells developed in quantity when cultures were supplemented with the supernatants from BALB/c 3T3 fibroblasts. in reduced numbers when supplemented with Swiss Albino 3T3 fibroblast supernatants. and not at all in culture media alone. By ultrastructural criteria, the newly developed mast cells did not achieve full maturity: they did continue to synthesize new granules and to undergo intragranular mauirational events. Small numbers of mature basophils persisted in suspension cultures. and many were undergoing piecemeal degranulation. Other cell lineages noted included eosinophils. neutrophils, macrophages and endothelial cells. We conclude that a factor(s) of fibroblast origin permits the differentiation and partial maturation ol' human mast cells from their agranular precursors in cord blood, but that fibroblasts must be physically present for complete maturation of these lineages to occur. [ABSTRACT FROM AUTHOR]

We performed ultrastructural cytochemistry to detect peroxidase in developmentally arrested human eosinophilic myelocytes. Human umbilical cord blood mononuclear cells were cultured for 21 days in the presence of murine-derived conditioned media, resulting in the development of eosinophilic myelocytes. Unlike normally developing eosinophilic myelocytes, which contain peroxidase in synthetic organelles (i.e. cisterns surrounding the nucleus and bounded by the rough endoplasmic reticulum and Golgi structures) and in immature and mature granules, the developmentally arrested cells showed ultrastructural evidence of decreased synthesis and secretory transport of peroxidase. Thus, peroxidase was generally absent in the perinuclear and rough endoplasmic cisterns, in Golgi structures, in immature granules and in the matrix compartment of most mature granules. Rather, bicompartmental specific granules displayed empty, peroxidase-negative matrix and central, peroxidase-negative core material. Peroxidase was present in perigranular vesicles, some of which were attached to granules. Such peroxidase-loaded transport vesicles are similar to those that effect piecemeal degranulation of mature human eosinophils cultured in rhIL-5-containing media [1]. These findings establish vesicle-mediated piecemeal degranulation in the secretor repertoire of immature human eosinophils and suggest the possibility that eosinophilic myelocytes may participate in vivo in important physiological and or pathological events that require selective secretion from the specific granule matrix. [ABSTRACT FROM AUTHOR]

Benzimidazoles, benzoxazoles, and benzothiazoles are prepared extremely rapidly. [ABSTRACT FROM AUTHOR]

Abstract Background Treatment of complex aortic pathologies involving the transverse arch with extensive involvement of the descending aorta remains a surgical challenge. Since clamshell incision provides superior exposure of the entire thoracic aorta, we evaluated the use of this technique for single-stage total arch replacement by arch vessel reconstruction. Methods The arch-first technique combined with clamshell incision was used in 38 cases of aneurysm and aortic disease in 2008 and 2009. Extensive total arch replacement was used with clamshell incision for reconstruction of arch vessels under deep hypothermic circulatory arrest. Results Overall 30-day mortality was 13%. The mean operating time was approximately 8 hours. Deep hypothermia resulted in mean CPB time exceeding 4.5 hours and mean duration of circulatory arrest was 25 minutes. The overall postoperative temporary and permanent neurologic dysfunction rates were 3% and 3% for elective and 3% and 0% for emergency surgery, respectively. All patients except the five who died in hospital were discharged without nursing care after an average post-operative hospital stay of 35 days. Conclusions The arch-first technique, combined with clamshell incision, provides expeditious replacement of the thoracic aorta with an acceptable duration of hypothermic circulatory arrest and minimizes the risk of retrograde atheroembolism by using antegrade perfusion.

Abstract Cardiac myxoma is the most common primary cardiac tumour, but infected cardiac myxoma is relatively rare. Infected cardiac myxoma is very fragile, and has a potential to lead to catastrophic disorder with systemic bacteremia, systemic mycotic embolism, and disseminated intravascular coagulation (DIC). We present here the successful surgical treatment of a case of infected left atrial myxoma with septic shock, DIC and cerebral infarction without hemorrahage. Collective review of 58 reported cases with infected cardiac myxoma revealed that surgical treatment for it were still challenging and its result was poor. Until date, only one successful surgical treatment for a case complicated by DIC and cerebral infarctions has been reported, and our report describes second such case of successful resection. Even though this report is limited to a case, only aggressive and prompt surgical intervention could relieve the intractable conditions in such a patient with extremely high risk.