Multispectral analysis of magnetic resonance images

Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.     

Mental health needs of children and young people

Nurses should have an understanding of the mental health needs of children and young people. In this article, Mervyn Townley introduces a number of concepts that relate to these needs.     

Beclomethasone decreases elevations in phosphodiesterase activity in human T lymphocytes

BACKGROUND: We recently reported that CD4+ T cells that have been activated in vivo or in vitro contain elevated cyclic adenosine monophosphate (cAMP) phosphodiesterase (PDE) activity. Since both phosphodiesterase inhibitors and glucocorticoids have anti-inflammatory activity, we sought to investigate the effect of beclomethasone on PDE activity. METHODS: PDE activity was measured in CD4+ T cells after 24 h of culture with beclomethasone. Cells were obtained from the peripheral blood of nonatopic persons (nCells), pre-seasonal (pCells), seasonal (within the first 2 weeks; sCells) and mid-seasonal (mCells) allergic rhinitics and asymptomatic allergic asthmatics (aCells). In addition, the effect of beclomethasone on Th2 cell lines and cells that had been activated in vitro with PHA or interleukin (IL)-2 was determined. RESULTS: PDE activity was decreased in a concentration-dependent manner by incubation of mCells, Th2 lines and PHA or IL-2-activated CD4+ T cells with beclomethasone (p < 0.05). However, beclomethasone did not modulate PDE activity in nCells, pCells, sCells, or aCells. CONCLUSIONS: Beclomethasone only decreases cAMP PDE activity in CD4+ T cells when it is increased by cell activation either in vitro or in vivo.     

高三尖杉酯碱酰胺的结构测定

三尖杉树皮粗提取物中的一个新生物碱—高三尖杉酯碱酰胺(homoharringtonamide)的结构,经质谱—质谱分析,初步建议为16。类似的酰胺类生物碱,例如三尖杉碱酰胺(cephalotaxamide,6)、11-羟基三尖杉碱酰胺(11-hydroxycephalotaxamide,9)、三尖杉酯碱酰胺(harfingtonamide,14)或异三尖杉酯碱酰胺(isoharringtonamide,15)也可能存在,后三者(9,14,15)尚未见报道。     

Serum profiles of insulin-like growth factors and their binding proteins in adults with growth hormone receptor deficiency treated with insulin like growth factor I

Six adult patients with growth hormone receptor deficiency (GHRD) (2 men, 4 women) with an identical defect in the growth hormone receptor (GHR) gene, were treated with recombinant human insulin-like growth factor I (IGF-I), 40 μgikg S.C. twice daily, for 7 days. Serum concentrations of IGF peptide and IGF binding protein-3 (IGFBP-3) were measured by specific radioimmunoassays; serum IGFBPs were also measured by Western ligand blotting. The size distribution of both IGF-I and IGF-II was measured in serum following size-exclusion fast-performance liquid chromatography. IGF-I treatment resulted in a normalization of serum IGF-I levels on days 1–7 of treatment and a decrease in serum IGF-II levels. The fall in IGF-II levels and the simultaneous rise in IGF-I levels, however, resulted in an unchanged total serum IGF level. The low IGFBP-3 values did not significantly change during treatment, whereas there was a slight increase in IGFBP-2 levels. Preliminary analysis of size-fractionated sera suggested an increase in IGF-I levels in the 40 and 150 kDa regions at the expense of IGF-II levels. The results suggest that despite the failure of IGF-I treatment to increase IGFBPs significantly, serum IGFBP concentrations were sufficient to maintain normal levels of IGF-I. 0 Laron syndrome, growth hormone receptor deficiency, insulin-like growth factors, insulin-like growth factor binding protein