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Notes: Abstract Background: To evaluate the diagnostic efficacy of fast T2-weighted magnetic resonance (MR) imaging sequences on image quality, hepatic lesion detection, and lesion conspicuity. Methods: Three breath-hold, fast T2-weighted sequences with turbo-spin-echo (TSE), half-Fourier acquisition single-shot TSE (HASTE), and inversion recovery (IR) HASTE techniques were examined for 43 lesions in 20 consecutive patients. Evaluation was performed qualitatively on image quality and lesion detectability and quantitatively on lesion conspicuity by using lesion/liver signal-intensity and contrast-to-noise ratios. Results: Artifacts were significantly less present on the HASTE sequence (p 〈 0.01). Both TSE and HASTE sequences detected 39 lesions (91% each); the IR HASTE sequence detected 37 (86%). IR HASTE sequence showed a significantly higher signal-intensity ratio than did the others (p 〈 0.01). Conclusions: Breath-hold TSE versus breath-hold HASTE or IR HASTE is still the most robust sequence in lesion detection, image quality, and lesion conspicuity. However, the HASTE sequence offers good lesion detection and image quality, and the IR HASTE has a better signal-intensity ratio.

Notes: Nonporous stainless steel particles with an average diameter of 25.5 μm and an average surface area of 215 cm2/g were used to study the adsorption of β-lactoglobulin (β-lg). Scanning electron microscopy of stainless steel particle surfaces with adsorbed β-lg showed an obvious eradication of crevices as protein was adsorbed. The adsorption process for β-lg was very rapid in the first 5 min and essentially reached equilibrium within 10 min. Precipitation of calcium phosphate onto the stainless steel surface was very slow compared to monolayer deposition of β-lg. A monolayer of β-lg adsorbed very tightly to the stainless steel surface and a significant fraction of the protein was irreversibly adsorbed. The amount of adsorbed protein decreased with increasing ratio of surface area to reaction volume. pH in the range 6.0–6.8 did not significantly affect the amount of adsorbed protein.

Notes: Freeze-thawing studies at different concentrations, using an actomyosin solution (extracted from Alaska pollock), revealed that an 8% (w/v) solution of oligosaccharides mixture (HBOS) was most effective in cryoprotection. During frozen storage (-18°C), HBOS showed cryoprotective effects similar to sucrose and a sucrose+sorbitol mixture (1:1). Surimi gel prepared with HBOS showed higher hardness and more dense microstructure than others, although water holding capacity was slightly lower than the gel with sucrose+sorbitol. HBOS containing gel showed lower whiteness than sucrose but no difference with sucrose+sorbitol. HBOS appeared to have good potential as a non-sweet cryoprotectant of fish protein.

Notes: We have investigated the evolution of molecular beam epitaxy (MBE)-grown, CdSe self-assembled quantum dots on ZnSe surfaces using microphotoluminescence techniques. Bare CdSe dots at room temperature undergo Ostwald ripening over a time scale measured in days. At the elevated temperatures maintained for MBE growth and dot formation, ripening is expected to progress much faster. Capping the dots with a thin ZnSe layer "freezes" the ripening, allowing one to sample different stages of the dot evolution and subsequent characterization. We have grown eleven samples, each with a different time interval, or growth interruption, between dot formation and capping; the growth interruption times ranging from 0 to 300 s, during which the samples were kept at 300 °C. Using microphotoluminescence spectroscopy, we have resolved the sharp emission peaks due to individual dots in each sample and, by analyzing the ensemble characteristics, have identified a new regime in the evolution of CdSe dots. © 1998 American Institute of Physics.

Notes: Background  A keloid results from excessive collagen deposition, the cause of which remains elusive. A thorough understanding of the pathophysiology of keloid tissue can help determine the most appropriate treatment strategy.Objectives  To assess the differences in gene expression between keloids and adjacent normal skin in order to define the genes involved in keloid formation.Methods  Three Korean patients with keloids underwent excision of the keloid and adjacent normal skin, which was used as the control. We investigated expression patterns of genes in the keloids and the normal skin using cDNA microarray and in situ hybridization techniques.Results  Nine genes in the keloid tissue were consistently upregulated over the 2·0 ratio compared with the normal control from the cDNA microarray composed of 3063 clones: collagen type I α1 (〈accessionId ref="info:ddbj-embl-genbank/NM_000088"〉NM_000088), DNA segment on chromosome 21 (unique) 2056 expressed sequence (D21S2056E, NNP-1, 〈accessionId ref="info:ddbj-embl-genbank/NM_003683"〉NM_003683), suppressor of Ty 5 homologue (〈accessionId ref="info:ddbj-embl-genbank/NM_003169"〉NM_003169), phosphoglycerate dehydrogenase (〈accessionId ref="info:ddbj-embl-genbank/NM_032692"〉NM_032692), adenosine triphosphate synthase β (〈accessionId ref="info:ddbj-embl-genbank/NM_001686"〉NM_001686), serine (or cysteine) proteinase inhibitor, clade H (heat shock protein 47, 〈accessionId ref="info:ddbj-embl-genbank/NM_001235"〉NM_001235), LIV-1 protein, oestrogen regulated (LIV-1, 〈accessionId ref="info:ddbj-embl-genbank/NM_012319"〉NM_012319), interleukin-11 receptor α (IL11RA, 〈accessionId ref="info:ddbj-embl-genbank/NM_004512"〉NM_004512) and carbonyl reductase 3 (CBR3, 〈accessionId ref="info:ddbj-embl-genbank/NM_001236"〉NM_001236). From the in situ hybridization study, the staining signals in the keloid tissue hybridized with anti sense probes of NNP-1 mRNA were stronger than signals in normal controls. Further, endothelial epithelium, but not the epidermis, expressed the signal equally in both keloid and normal control tissue.Conclusions  We identified nine upregulated genes in keloid tissue using cDNA microarray. Of the nine, the NNP-1 gene was confirmed by topological information using the in situ hybridization technique. We conclude that these nine genes, especially NNP-1, probably contribute either directly or indirectly to keloid formation.

Notes: We use micro- and nano-photoluminescence to study the temperature-dependent excitonic emission from CdSe quantum dots embedded in a ZnSe matrix. By varying the spatial resolution from 200 nm to 1.7 μm, we are able to study the temperature dependence of the ultranarrow (∼200 μeV) emission from excitons confined to single quantum dots, as well as statistical ensembles of up to 200 dots. By measuring the quenching of the photoluminescence (PL) with temperature, we find compelling evidence that the PL emission from these samples results from two different kinds of states. Similar to previous work, we find that a broad PL line persists to 300 K with an activation energy of ∼40 meV. However, we find that the ultranarrow lines are quenched at about 60 K, indicating an effective activation energy of only 4.0 meV. © 1999 American Institute of Physics.

Notes: Abstract: The present study was undertaken to investigate changes in haematology parameters over the course of gestation in Sprague–Dawley rats. Blood samples were alternatively collected from two groups of pregnant rats on gestational days (GD) 0, 3, 6, 9, 12, 15, 18 and 21 using a needle catheter. Red blood cell counts, haemoglobin and haematocrit on GD 6, 12, 18 and 21 were lower than those of normal non-pregnant rats. These values declined progressively during the course of gestation and reached minimum levels on GD 18 or 21. There were no differences in mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration between pregnant and non-pregnant rats. Platelet counts in pregnant rats increased gradually with advancing gestation and were much higher on GD 15 and 21 than in nonpregnant rats. Total white blood cell and lymphocyte counts on GD 0–15 were higher than those of non-pregnant rats. These values increased maximally by GD 6 and then decreased progressively to a nadir on GD 21. Neutrophil counts on GD 9–21 were higher than non-pregnant rat values. The neutrophils increased to a peak level on GD 12 and then steadily decreased. These data can be used not only as a historical database for the effective evaluation of data from reproductive toxicology studies, but also as a contribution to biological characterisation of Sprague–Dawley rats.