Useful model organisms,indicators, or both? Ground beetles (Coleoptera,Carabidae) reflecting environmental conditions

Classic studies have successfully linked single-species abundances, life-history traits, assemblage structures and biomass of carabid beetles to past and present, human-caused environmental impacts and variation in ‘natural’ conditions. This evidence has led many to suggest carabids to function as ‘indicators’ − a term that bears multiple meanings. Here, a conservation-oriented definition for an indicator is used, carabid indicator potential from seven views is evaluated, and ways to proceed in indicator research are discussed. (1) Carabid species richness poorly indicates the richness and abundance of other taxa, which underlines the importance of using multiple taxa in environmental assessments. The ability of assemblage indices and specialist or functional-group abundances to reflect rare species and habitats should be examined in detail. (2) Experimental evidence suggests that carabids may potentially serve as keystone indicators. (3) Carabids are sensitive to human-altered abiotic conditions, such as pesticide use in agro-ecosystems and heavy metal contamination of soils. Carabids might thus reflect ecological sustainability and ‘ecosystem health’. (4) Carabid assemblages host abundant species characteristic of particular habitat types or successional stages, which makes them promising dominance indicators. (5) Carabids reflect variation in ‘natural’ conditions, but vegetation and structural features are more commonly adopted as condition indicators. Carabids nevertheless provide yet another, equally accurate, view on the structure of the environment. (6) Carabids may function as early-warning signalers, as suggested by recent studies linking climate and carabid distributions. (7) Carabids reflect natural and human-caused disturbances and management, but the usefulness of these responses for conservation purposes requires further research. In summary, European carabids appear useful model organisms and possibly indicators because they are diverse, taxonomically and ecologically well-known, efficiently reflect biotic and abiotic conditions, are relevant at multiple spatial scales, and are easy to collect in sufficiently large numbers to allow statistical analyses. The assumption that carabid responses would reflect rare environmental conditions or the responses of rare and threatened species ‒ crucial information for conservationists and managers ‒ has not yet been critically evaluated. Even if it holds, the usefulness will be context dependent: species and their populations vary, conditions vary, questions put forward vary, and assessment goals vary.     

肿瘤标志物联合检测在乳腺癌早期诊断中的应用

目的：探讨肿瘤标志物癌胚抗原（CEA）、糖链抗原19-9（CA19-9）、糖链抗原15-3（CA15-3）联合检测在乳腺癌早期诊断中的应用价值。方法：检测87例乳腺癌患者,55例乳腺良性肿瘤患者和35例健康人血清中CEA、CA19-9、CA153等肿瘤标志物的水平及3种标志物不同组合对乳腺癌的阳性检出率。结果：乳腺癌患者3种肿瘤标志物显著高于正常对照组及乳腺良性肿瘤组（P〈0.01）。3项标志物不同组合对不同分期乳腺癌检出的敏感性均高于单项标志物。其中CEA＋CA199＋CA153组合的检出敏感性较其他组合均高,特别是对早期患者检出率明显提高。结论：CEA＋CA199＋CA153联合检测能提高乳腺癌的早期诊断率。     

Will krill fare well under Southern Ocean acidification?

Antarctic krill embryos and larvae were experimentally exposed to 380 (control), 1000 and 2000 µatm pCO₂ in order to assess the possible impact of ocean acidification on early development of krill. No significant effects were detected on embryonic development or larval behaviour at 1000 µatm pCO₂; however, at 2000 µatm pCO₂ development was disrupted before gastrulation in 90 per cent of embryos, and no larvae hatched successfully. Our model projections demonstrated that Southern Ocean sea water pCO₂ could rise up to 1400 µatm in krill''s depth range under the IPCC IS92a scenario by the year 2100 (atmospheric pCO₂ 788 µatm). These results point out the urgent need for understanding the pCO₂-response relationship for krill developmental and later stages, in order to predict the possible fate of this key species in the Southern Ocean.     

Survival and sublethal responses of early life stages of pike exposed to low pH in artificial post-mining lake water

The threshold pH for survival of early life stages of pike Esox lucius in post-mining lakes was determined in a laboratory experiment using artificial water characterized by high concentrations of dissolved Ca, Al, Fe, Mn and SO2/4⁻. At pH 3·50–4·00, high mortality was observed before hatching. At pH 4·00 and 4·25, hatching rates were reduced compared with the controls (pH 7·40), and many embryos died in a partly hatched state. Hatching success of embryos exposed to pH levels of 4·50 or higher was not affected. However, at pH 5·00 many newly hatched embryos were deformed. Furthermore, pike exposed to pH 4·00–5·00 did not start feeding. At pH 4·75 and below, mortality increased to 100%, and at pH 5·00, only few eleutheroembryos which were in extremely poor condition survived to the end of the experiment. At pH 5·50, survival was in the same range as in the control group, but growth was reduced. Therefore, early life stages of pike are expected to survive in Lustian post-mining lakes when a pH of 5·50 and above is reached and maintained.     

Comparative assessment of fermentation techniques useful in the processing of ogi

Ogiis processed traditionally by the use of uncontrolled spontaneous fermentation of maize, sorghum and millet. In this study, traditionally applied spontaneous fermentation was compared with accelerated batch fermentation (or back-slopping) and the use of starter cultures to initiate fermentation. Lactic acid bacteria populations comprised 95 of the total viable bacteria and remained prominent throughout the fermentations, while number of moulds and coliform bacteria declined as the fermentation progressed. The fermentation method involving the application of starter culture helps most to control the prevalence of coliforms and moulds. Lactic acid bacteria, such as Lactococcus raffinolactis, Pediococcussp.,Pediococcus pentosaceus, Lactobacillus plantarum, Lb. suebicus and Lb. brevis,were isolated at different processing stages of ogi using accelerated batch fermentation (back-slopping) technique. Highest increase in acidity was observed immediately after wet-milling and sieving fermenting maize grains at 28 and 48 h. Sharp increases in the reducing sugar levels were noted between 24 and 28 h of fermentations during wet-milling and sieving processes.     

Mechanisms of sex steroid effects on bone

Sex steroids play a major role in the regulation of bone turnover. Thus, gonadectomy in either sex is associated with an increase in bone remodeling, increased bone resorption, and a relative deficit in bone formation, resulting in accelerated bone loss. Recent physiological studies have established an important role for estrogen in regulating bone turnover not only in females, but also in males. Studies in mice with knock out of the estrogen receptor, aromatase, or androgen receptor have provided important insights into the in vivo mechanisms of sex steroid action on bone. The cellular and molecular mediators of sex steroid effects on the bone-forming osteoblasts and bone-resorbing osteoclasts are also being increasingly better defined. Estrogen inhibits bone remodeling by concurrently suppressing osteoblastogenesis and osteoclastogenesis from marrow precursors. Both estrogen and androgens inhibit bone resorption via effects on the receptor activator of NF-kappaB ligand (RANKL)/RANK/osteoprotegerin system, as well as by reducing the production of a number of pro-resorptive cytokines, along with direct effects on osteoclast activity and lifespan. Sex steroid effects on bone formation are also likely mediated by multiple mechanisms, including a prolongation of osteoblast lifespan via non-genotropic mechanisms, as well as effects on osteoblast differentiation and function. These pleiotropic actions of sex steroids on virtually all aspects of bone metabolism belie the importance of the skeleton not only in providing structural support for the body and in locomotion, but also as a dynamic tissue responsive, among other things, to the reproductive needs of the organism for calcium.     

PrP(106-126) activates neuronal intracellular kinases and Egr1 synthesis through activation of NADPH-oxidase independently of PrPc

Prion diseases are characterised by severe neural lesions linked to the presence of an abnormal protease-resistant isoform of cellular prion protein (PrPc). The peptide PrP(106-126) is widely used as a model of neurotoxicity in prion diseases. Here, we examine in detail the intracellular signalling cascades induced by PrP(106-126) in cortical neurons and the participation of PrPc. We show that PrP(106-126) induces the activation of subsets of intracellular kinases (e.g., ERK1/2), early growth response 1 synthesis and induces caspase-3 activity, all of which are mediated by nicotinamide adenine dinucleotide phosphate hydrogen-oxidase activity and oxidative stress. However, cells lacking PrPc are similarly affected after peptide exposure, and this questions the involvement of PrPc in these effects.     

Polyomavirus EGFP-pseudocapsids: analysis of model particles for introduction of proteins and peptides into mammalian cells

A vector for preparation of mouse polyomavirus capsid-like particles for transfer of foreign peptides or proteins into cells was constructed. Model pseudocapsids carrying EGFP fused with the C-terminal part of the VP3 minor protein (EGFP-VLPs) have been prepared and analysed for their ability to be internalised and processed by mouse cells and to activate mouse and human dendritic cells (DC) in vitro. EGFP-VLPs entered mouse epithelial cells, fibroblasts and human and mouse DC efficiently and were processed by both, lysosomes and proteasomes. Surprisingly, they did not induce upregulation of DC co-stimulation molecules or maturation markers in vitro; however, they did induce interleukin 12 secretion.