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52.
Local knowledge systems are not considered in the conservation of fragile seagrass marine ecosystems. In fact, little is known about the utility of seagrasses in local coastal communities. This is intriguing given that some local communities rely on seagrasses to sustain their livelihoods and have relocated their villages to areas with a rich diversity and abundance of seagrasses. The purpose of this study is to assist in conservation efforts regarding seagrasses through identifying Traditional Ecological Knowledge (TEK) from local knowledge systems of seagrasses from 40 coastal communities along the eastern coast of India. We explore the assemblage of scientific and local traditional knowledge concerning the 1. classification of seagrasses (comparing scientific and traditional classification systems), 2. utility of seagrasses, 3. Traditional Ecological Knowledge (TEK) of seagrasses, and 4. current conservation efforts for seagrass ecosystems. Our results indicate that local knowledge systems consist of a complex classification of seagrass diversity that considers the role of seagrasses in the marine ecosystem. This fine-scaled ethno-classification gives rise to five times the number of taxa (10 species = 50 local ethnotaxa), each with a unique role in the ecosystem and utility within coastal communities, including the use of seagrasses for medicine (e.g., treatment of heart conditions, seasickness, etc.), food (nutritious seeds), fertilizer (nutrient rich biomass) and livestock feed (goats and sheep). Local communities are concerned about the loss of seagrass diversity and have considerable local knowledge that is valuable for conservation and restoration plans. This study serves as a case study example of the depth and breadth of local knowledge systems for a particular ecosystem that is in peril.  相似文献   
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1. Arbuscular mycorrhizal fungi (AMF) commonly colonise isoetid species inhabiting oxygenated sediments in oligotrophic lakes but are usually absent in other submerged plants. We hypothesised that organic enrichment of oligotrophic lake sediments reduces AMF colonisation and hyphal growth because of sediment O2 depletion and low carbon supply from stressed host plants. 2. We added organic matter to sediments inhabited by isoetids and measured pore‐water chemistry (dissolved O2, inorganic carbon, Fe2+ and ), colonisation intensity of roots and hyphal density after 135 days of exposure. 3. Addition of organic matter reduced AMF colonisation of roots of both Lobelia dortmanna and Littorella uniflora, and high additions stressed the plants. Even small additions of organic matter almost stopped AMF colonisation of initially un‐colonised L. uniflora, though without reducing plant growth. Mean hyphal density in sediments was high (6 and 15 m cm?3) and comparable with that in terrestrial soils (2–40 m cm?3). Hyphal density was low in the upper 1 cm of isoetid sediments, high in the main root zone between 1 and 8 cm and positively related to root density. Hyphal surface area exceeded root surface area by 1.7–3.2 times. 4. We conclude that AMF efficiently colonise isoetids in oligotrophic sediments and form extensive hyphal networks. Small additions of organic matter to sediments induce sediment anoxia and reduce AMF colonisation of roots but cause no apparent plant stress. High organic addition induces night‐time anoxia in both the sediment and the plant tissue. Tissue anoxia reduces root growth and AMF colonisation, probably because of restricted translocation of nutrient ions and organic solutes between roots and leaves. Isoetids should rely on AMF for P uptake on nutrient‐poor mineral sediments but are capable of growing without AMF on organic sediments.  相似文献   
54.
Cell-mediated immune responses are known to be critical for control of mycobacterial infections whereas the role of B cells and humoral immunity is unclear. B cells can modulate immune responses by secretion of immunoglobulin, production of cytokines and antigen-presentation. To define the impact of B cells in the absence of secreted immunoglobulin, we analyzed the progression of Mycobacterium tuberculosis (Mtb) infection in mice that have B cells but which lack secretory immunoglobulin (AID−/−µS−/−mice). AID−/−µS−/− mice accumulated a population of activated B cells in the lungs when infected and were more susceptible to aerosol Mtb when compared to wild type (C57BL/6) mice or indeed mice that totally lack B cells. The enhanced susceptibility of AID−/−µS−/− mice was not associated with defective T cell activation or expression of a type 1 immune response. While delivery of normal serum to AID−/−µS−/− mice did not reverse susceptibility, susceptibility in the spleen was dependent upon the presence of B cells and susceptibility in the lungs of AID−/−µS−/−mice was associated with elevated expression of the cytokines IL-6, GM-CSF, IL-10 and molecules made by alternatively activated macrophages. Blocking of IL-10 signaling resulted in reversal of susceptibility in the spleens and lungs of AID−/−µS−/− mice. These data support the hypothesis that B cells can modulate immunity to Mtb in an organ specific manner via the modulation of cytokine production and macrophage activation.  相似文献   
55.
The glucan-binding protein-A (GbpA) of Streptococcus mutans has been shown to contribute to the architecture of glucan-dependent biofilms formed by this species and influence virulence in a rat model. As S. mutans synthesizes multiple glucosyltransferases and nonglucosyltransferase glucan-binding proteins (GBPs), it is possible that there is functional redundancy that overshadows the full extent of GbpA contributions to S. mutans biology. Glucan-associated properties such as adhesion, aggregation, and biofilm formation were examined independently of other S. mutans GBPs by cloning the gbpA gene into a heterologous host, Streptococcus gordonii, and derivatives with altered or diminished glucosyltransferase activity. The presence of GbpA did not alter dextran-dependent aggregation nor the initial sucrose-dependent adhesion of S. gordonii. However, expression of GbpA altered the biofilm formed by wild-type S. gordonii as well as the biofilm formed by strain CH107 that produced primarily alpha-1,6-linked glucan. Expression of gbpA did not alter the biofilm formed by strain DS512, which produced significantly lower quantities of parental glucan. These data are consistent with a role for GbpA in facilitating the development of biofilms that harbor taller microcolonies via binding to alpha-1,6-linkages within glucan. The magnitude of the GbpA effect appears to be dependent on the quantity and linkage of available glucan.  相似文献   
56.
The degradation of type II collagen has been associated with the pathology of osteoarthritis (OA). Matrix metalloproteinases (MMPs) are enzymes that are responsible for catalyzing the degradation of collagen and, therefore, are pursued as potential targets for the treatment of OA. Collagen-derived peptides identified as a reflection of in vivo MMP activity have been investigated as target biomarkers of MMP activity as well as potential biomarkers of OA disease state and/or progression. An immunoaffinity liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay developed for the quantification of the most abundant urinary type II collagen neoepitope (uTIINE) peptide, a 45-mer with 5 HO-proline residues resulting from MMP-13-catalyzed degradation, was validated for clinical use. Validation experiments were designed with attention to specific challenges related to quantification of endogenous analytes. The validated method is sensitive, selective, accurate (<15% relative error) and precise (<15% coefficient of variation) over a linear range of 0.156-7.50 ng/ml. Sample stability and inter- and intrasubject variability were evaluated in the urine of normal and OA populations. The method was applied to analyze human urine samples from clinical studies investigating the utility of uTIINE as a potential biomarker for OA.  相似文献   
57.
Recently, increased attention has been directed towards medicinal extracts as potential new drug candidates for dementia. Ginger has long been used as an important ingredient in cooking and traditional herbal medicine. In particular, ginger has been known to have disease-modifying effects in Alzheimer's disease (AD). However, there is no evidence of which constituents of ginger exhibit therapeutic effects against AD. A growing number of experimental studies suggest that 6-shogaol, a bioactive component of ginger, may play an important role as a memory-enhancing and anti-oxidant agent against neurological diseases. 6-Shogaol has also recently been shown to have anti-neuroinflammatory effects in lipopolysaccharide (LPS)-treated astrocytes and animal models of Parkinson’s disease, LPS-induced inflammation and transient global ischemia. However, it is still unknown whether 6-shogaol has anti-inflammatory effects against oligomeric forms of the Aβ (AβO) in animal brains. Furthermore, the effects of 6-shogaol against memory impairment in dementia models are also yet to be investigated. In this study, we found that administration of 6-shogaol significantly reduced microgliosis and astrogliosis in intrahippocampal AβO-injected mice, ameliorated AβO and scopolamine-induced memory impairment, and elevated NGF levels and pre- and post-synaptic marker in the hippocampus. All these results suggest that 6-shogaol may play a role in inhibiting glial cell activation and reducing memory impairment in animal models of dementia.  相似文献   
58.
Objective To compare the effects of laparoscopic hysterectomy and abdominal hysterectomy in the abdominal trial, and laparoscopic hysterectomy and vaginal hysterectomy in the vaginal trial.Design Two parallel, multicentre, randomised trials.Setting 28 UK centres and two South African centres.Participants 1380 women were recruited; 1346 had surgery; 937 were followed up at one year.Primary outcome Rate of major complications.Results In the abdominal trial laparoscopic hysterectomy was associated with a higher rate of major complications than abdominal hysterectomy (11.1% v 6.2%, P = 0.02; difference 4.9%, 95% confidence interval 0.9% to 9.1%) and the number needed to treat to harm was 20. Laparoscopic hysterectomy also took longer to perform (84 minutes v 50 minutes) but was less painful (visual analogue scale 3.51 v 3.88, P = 0.01) and resulted in a shorter stay in hospital after the operation (3 days v 4 days). Six weeks after the operation, laparoscopic hysterectomy was associated with less pain and better quality of life than abdominal hysterectomy (SF-12, body image scale, and sexual activity questionnaires).In the vaginal trial we found no evidence of a difference in major complication rates between laparoscopic hysterectomy and vaginal hysterectomy (9.8% v 9.5%, P = 0.92; difference 0.3%, -5.2% to 5.8%), and the number needed to treat to harm was 333. We found no evidence of other differences between laparoscopic hysterectomy and vaginal hysterectomy except that laparoscopic hysterectomy took longer to perform (72 minutes v 39 minutes) and was associated with a higher rate of detecting unexpected pathology (16.4% v 4.8%, P = < 0.01). However, this trial was underpowered.Conclusions Laparoscopic hysterectomy was associated with a significantly higher rate of major complications than abdominal hysterectomy. It also took longer to perform but was associated with less pain, quicker recovery, and better short term quality of life. The trial comparing vaginal hysterectomy with laparoscopic hysterectomy was underpowered and is inconclusive on the rate of major complications; however, vaginal hysterectomy took less time.  相似文献   
59.
Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster female mice maintained in the hindlimb-unloading model (Aviles H, Belay T, Fountain K, Vance M, and Sonnenfeld G. J Appl Physiol 95: 73-80, 2003; Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 110: 262-268, 2002). This is a model of some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. Active hexose correlated compound (AHCC), extracted from Basidiomycete mushrooms, has been shown to induce enhancement of immune responses, including enhanced natural killer activity. In the present study, AHCC was orally administered to mice to determine whether the treatment could decrease immunosuppression and mortality of mice maintained in the hindlimb-unloaded model and infected with Klebsiella pneumoniae. The results of the present study showed that administration of AHCC by gavage for 1 wk (1 g/kg body wt) before suspension and throughout the 10-day suspension period yielded significant beneficial effects for the hindlimb-unloaded group, including 1). decreased mortality, 2). increased time to death, and 3). increased ability to clear bacteria. The results suggest that AHCC can decrease the deleterious effects of the hindlimb-unloading model on immunity and resistance to infection.  相似文献   
60.
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