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1.
Recent studies indicate that the discriminatory power of the core DNA barcodes (rbcLa + matK) for land plants may have been overestimated since their performance have been tested only on few closely related species. In this study we focused mainly on how the addition of complementary barcodes (nrITS and trnH-psbA) to the core barcodes will affect the performance of the core barcodes in discriminating closely related species from family to section levels. In general, we found that the core barcodes performed poorly compared to the various combinations tested. Using multiple criteria, we finally advocated for the use of the core + trnH-psbA as potential DNA barcode for the family Combretaceae at least in southern Africa. Our results also indicate that the success of DNA barcoding in discriminating closely related species may be related to evolutionary and possibly the biogeographic histories of the taxonomic group tested.  相似文献   
2.
Degradation and the antioxidative effect of Na-, Zn-, Co-, Cu-, and Mn-hyaluronic acid (HA) associates were studied. Our findings revealed the protective effect of certain counterions against ROS-induced HA degradation. We could also separate the antioxidative effect of certain counterions from that of the HA by examining the effect of the counterions in their free ionic forms. The result showed that metal ions with altering oxidative status (Co(2+), Cu(2+), Mn(2+)) proved to be effective in themselves or their effect added to that of HA when HA was also effective. Moreover, the effects of Co-HA against z.rad;O(2)(-) and of Mn-HA against ONOO(-) as well as the synergic effect of Zn-HA associates where Zn(2+) is of fixed oxidative status were attributed to the structure-stabilizing complex formed between certain counterions and HA. Our examination also concerned the influence of HA associates on the indirect antioxidation related to Fe(2+) chelating. The individual effects of Zn(2+), Co(2+), and Cu(2+) were only detectable, which could be explained by the competitive displacement of ferrous from its binding site.  相似文献   
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The inhibition of cyclooxygenase enzymes plays an important role in the treatment of inflammatory diseases. N-Hydroxy-4-(5-methyl-3-phenylisoxazol-4-yl)benzenesulfonamide (3)—a primary metabolite of the highly selective COX-2 inhibitor valdecoxib—was synthesized and stabilized as its monohydrate (3a·H2O). The anti-inflammatory properties of 3a·H2O were investigated in carrageenan-induced edema and in acute and chronic pain models. Based on our biological investigation, we conclude that N-hydroxy-valdecoxib 3a is an active metabolite of valdecoxib.  相似文献   
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Synthesis of nitrone derivatives of trolox is described. Their biological evaluation was performed in vitro for scavenging different free radicals, inhibiting Fe(2+)-induced lipid peroxidation, and in vivo in a permanent middle cerebral artery occlusion model in mice. New compounds exert pharmacological activities comparable to or better than those of trolox or nitrone-type reference compounds.  相似文献   
7.
Attempts to investigate the drivers of invasion success are generally limited to the biological and evolutionary traits distinguishing native from introduced species. Although alien species introduced to the same recipient environment differ in their invasion intensity – for example, some are “strong invaders”; others are “weak invaders” – the factors underlying the variation in invasion success within alien communities are little explored. In this study, we ask what drives the variation in invasion success of alien mammals in South Africa. First, we tested for taxonomic and phylogenetic signal in invasion intensity. Second, we reconstructed predictive models of the variation in invasion intensity among alien mammals using the generalized linear mixed‐effects models. We found that the family Bovidae and the order Artiodactyla contained more “strong invaders” than expected by chance, and that such taxonomic signal did not translate into phylogenetic selectivity. In addition, our study indicates that latitude, gestation length, social group size, and human population density are only marginal determinant of the variation in invasion success. However, we found that evolutionary distinctiveness – a parameter characterising the uniqueness of each alien species – is the most important predictive variable. Our results indicate that the invasive behavior of alien mammals may have been “fingerprinted” in their evolutionary past, and that evolutionary history might capture beyond ecological, biological and life‐history traits usually prioritized in predictive modeling of invasion success. These findings have applicability to the management of alien mammals in South Africa.  相似文献   
8.

Background

Governments and donors all over Africa are searching for sustainable, affordable and cost-effective ways to improve the quality of malaria case management. Widespread deficiencies have been reported in the prescribing and counselling practices of health care providers treating febrile patients in both public and private health facilities. Cameroon is no exception with low levels of adherence to national guidelines, the frequent selection of non-recommended antimalarials and the use of incorrect dosages. This study evaluates the effectiveness and cost-effectiveness of introducing two different provider training packages, alongside rapid diagnostic tests (RDTs), designed to equip providers with the knowledge and practical skills needed to effectively diagnose and treat febrile patients. The overall aim is to target antimalarial treatment better and to facilitate optimal use of malaria treatment guidelines.

Methods/Design

A 3-arm stratified, cluster randomized trial will be conducted to assess whether introducing RDTs with provider training (basic or enhanced) is more cost-effective than current practice without RDTs, and whether there is a difference in the cost effectiveness of the provider training interventions. The primary outcome is the proportion of patients attending facilities that report a fever or suspected malaria and receive treatment according to malaria guidelines. This will be measured by surveying patients (or caregivers) as they exit public and mission health facilities. Cost-effectiveness will be presented in terms of the primary outcome and a range of secondary outcomes, including changes in provider knowledge. Costs will be estimated from a societal and provider perspective using standard economic evaluation methodologies.

Trial Registration

ClinicalTrials.gov: NCT00981877  相似文献   
9.
Pauci-immune focal necrotizing glomerulonephritis (FNGN) is a severe inflammatory disease associated with autoantibodies to neutrophil cytoplasmic antigens (ANCA). Here we characterize autoantibodies to lysosomal membrane protein-2 (LAMP-2) and show that they are a new ANCA subtype present in almost all individuals with FNGN. Consequently, its prevalence is nearly twice that of the classical ANCAs that recognize myeloperoxidase or proteinase-3. Furthermore, antibodies to LAMP-2 cause pauci-immune FNGN when injected into rats, and a monoclonal antibody to human LAMP-2 (H4B4) induces apoptosis of human microvascular endothelium in vitro. The autoantibodies in individuals with pauci-immune FNGN commonly recognize a human LAMP-2 epitope (designated P(41-49)) with 100% homology to the bacterial adhesin FimH, with which they cross-react. Rats immunized with FimH develop pauci-immune FNGN and also develop antibodies to rat and human LAMP-2. Finally, we show that infections with fimbriated pathogens are common before the onset of FNGN. Thus, FimH-triggered autoimmunity to LAMP-2 provides a previously undescribed clinically relevant molecular mechanism for the development of pauci-immune FNGN.  相似文献   
10.
The presence of hydroxyproline, and the determination of the ratio of the secondary amino acids proline to hydroxyproline, in amino acid hydrolysates specifically identifies collagen and collagen peptides. o-Phthalaldehyde, and then 9-fluorenylmethyl chloroformate, were used to carry out sequential prederivatization of amino acid hydrolysates in an in-line high-performance liquid chromatography sample loop. After derivatization, reversed-phase high-performance liquid chromatography with a C-18 ODS Hypersil cartridge column was used to resolve the hydroxyproline and proline from all primary amino acids, with resolution and detection of hydroxyproline and proline within 2.0 and 2.8 min, respectively, at concentrations in the range of picomoles per microliter of derivatized amino acid. The assay has a turnaround time of 10.75 min.  相似文献   
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