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891.
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Lange CA Kotte K Smit M van Deventer PW van Rensburg L 《International journal of phytoremediation》2012,14(9):908-924
Rehabilitation of mine tailings dams is often a challenge due to a lack of nutrients and a poor humus reservoir prevailing in tailings soils. This is especially true for establishing longer lived species such as trees. For these reasons the effects of different soil ameliorants (woodchips compost, vermicompost, mature sewage sludge), added to the root system of Karee (Searsia lancea) saplings were tested in pot trials. Those pots were filled with platinum and gold tailings substrate as well as red clay soil, respectively. For three months plants remained in a greenhouse and were subsequently moved to a test field outside. Throughout the test period regular chl a fluorescence measurements were taken and subjected to JIP-test quantifying changes in photosynthetic vitality status. Additionally, growth measurements and one-off leaf analysis were carried out. Test plants growing on mine tailings experienced an up to 35% higher average photosynthetic vitality (PI(ABS)) and improved nutrient supply, when treated with mature sewage sludge. Consequently, sewage sludge treated plants showed a higher biomass build-up rate and an up to 55% higher diameter growth, compared to control. In summary the experiments present a low cost alternative for reforestation enterprises on platinum and gold tailings dams in South Africa. 相似文献
893.
Kamala Thriemer Benedikt B. Ley Shaali S. Ame Jaqueline L. Deen Gi Deok Pak Na Yoon Chang Ramadhan Hashim Wolfgang Hellmut Schmied Clara Jana-Lui Busch Shanette Nixon Anne Morrissey Mahesh K. Puri R. Leon Ochiai Thomas Wierzba John D. Clemens Mohammad Ali Mohammad S. Jiddawi Lorenz von Seidlein Said M. Ali 《PloS one》2012,7(12)
Background
The gold standard for diagnosis of typhoid fever is blood culture (BC). Because blood culture is often not available in impoverished settings it would be helpful to have alternative diagnostic approaches. We therefore investigated the usefulness of clinical signs, WHO case definition and Widal test for the diagnosis of typhoid fever.Methodology/Principal Findings
Participants with a body temperature ≥37.5°C or a history of fever were enrolled over 17 to 22 months in three hospitals on Pemba Island, Tanzania. Clinical signs and symptoms of participants upon presentation as well as blood and serum for BC and Widal testing were collected. Clinical signs and symptoms of typhoid fever cases were compared to other cases of invasive bacterial diseases and BC negative participants. The relationship of typhoid fever cases with rainfall, temperature, and religious festivals was explored. The performance of the WHO case definitions for suspected and probable typhoid fever and a local cut off titre for the Widal test was assessed. 79 of 2209 participants had invasive bacterial disease. 46 isolates were identified as typhoid fever. Apart from a longer duration of fever prior to admission clinical signs and symptoms were not significantly different among patients with typhoid fever than from other febrile patients. We did not detect any significant seasonal patterns nor correlation with rainfall or festivals. The sensitivity and specificity of the WHO case definition for suspected and probable typhoid fever were 82.6% and 41.3% and 36.3 and 99.7% respectively. Sensitivity and specificity of the Widal test was 47.8% and 99.4 both forfor O-agglutinin and H- agglutinin at a cut-off titre of 1∶80.Conclusions/Significance
Typhoid fever prevalence rates on Pemba are high and its clinical signs and symptoms are non-specific. The sensitivity of the Widal test is low and the WHO case definition performed better than the Widal test. 相似文献894.
Natalie L. Payne Ashanti Dantanarayana Guizhi Sun Leon Moussa Sally Caine Courtney McDonald Daniella Herszfeld Claude C.A. Bernard Christopher Siatskas 《Cell Adhesion & Migration》2012,6(3):179-189
Mesenchymal stem/stromal cells (MSCs) can be isolated from most adult tissues and hold considerable promise for tissue regenerative therapies. Some of the potential advantages that MSCs have over other adult stem cell types include: (1) their relative ease of isolation, culture and expansion; (2) their immunomodulatory properties; (3) they can provide trophic support to injured tissues; (4) they can be transduced by retroviral vectors at a high efficiency; (5) they have an ability to home to sites of inflammation and injury. Collectively these characteristics suggest that MSCs are attractive vehicles for cell and gene therapy applications. In the current study, we investigated whether transplantation of human adipose-derived MSCs (Ad-MSCs) engineered to overexpress the anti-inflammatory cytokine interleukin (IL)-4 was efficacious in experimental autoimmune encephalomyelitis (EAE). Ad-MSCs transduced with a bicistronic lentiviral vector encoding mouse IL-4 and enhanced green fluorescent protein (Ad-IL4-MSCs) stably expressed, relatively high levels of both transgenes. Importantly the phenotypic and functional attributes of Ad-IL4-MSCs, such as the expression of homing molecules and differentiation capacity, was not altered by the transduction process. Notably, the early administration of Ad-IL4-MSCs in mice with EAE at the time of T-cell priming attenuated clinical disease. This protective effect was associated with a reduction in peripheral MOG-specific T-cell responses and a shift from a pro- to an anti-inflammatory cytokine response. These data suggest that the delivery of Ad-MSCs genetically engineered to express anti-inflammatory cytokines may provide a rational approach to promote immunomodulation and tissue protection in a number of inflammatory and degenerative diseases including multiple sclerosis. 相似文献
895.
Calcium orthophosphate bone cements (CPCs) are widely used in orthopedic surgery. Implants are highly susceptible to infection and often lead to the formation of microbial biofilms. Antibiotics are often incorporated into bone cement to prevent infection. The increase in the number of microorganisms acquiring or developing resistance to antibiotics, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), is a major concern. Bacteriocins (antimicrobial peptides) offer an alternative to antibiotics. Their mode of activity involves permanent destabilization of the plasma membrane of target cells. A number of broad-spectrum bacteriocins produced by lactic acid bacteria and Bacillus spp. have recently been reported. In this REVIEW the major characteristics of calcium phosphate bone cements, prosthetic joint-associated infections, and treatment of these infections is discussed. The role of antimicrobial agents in CPCs is discussed and the possibility of incorporating bacteriocins in prosthetic devices is investigated. 相似文献
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900.
A comparison of urinary mercury between children with autism spectrum disorders and control children
Wright B Pearce H Allgar V Miles J Whitton C Leon I Jardine J McCaffrey N Smith R Holbrook I Lewis J Goodall D Alderson-Day B 《PloS one》2012,7(2):e29547