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91.
92.

Background

This aim of this study is to report upon traditional knowledge and use of wild medicinal plants by the Highlanders of Lukomir, Bjela?nica, Bosnia and Herzegovina (B&H). The Highlanders are an indigenous community of approximately 60 transhumant pastoralist families who speak Bosnian (Bosanski) and inhabit a highly biodiverse region of Europe. This paper adds to the growing record of traditional use of wild plants within isolated communities in the Balkans.

Methods

An ethnobotanical study using consensus methodology was conducted in Lukomir in Bjela?nica’s mountains and canyons. Field work involved individual semi-structured interviews during which informants described plants, natural product remedies, and preparation methods on field trips, garden tours, while shepherding, or in settings of their choice. Plant use categories were ranked with informant consensus factor and incorporated into a phylogenetic tree. Plants cited were compared to other ethnobotanical surveys of the country.

Results

Twenty five people were interviewed, resulting in identification of 58 species (including two subspecies) from 35 families, which were cited in 307 medicinal, 40 food, and seven material use reports. Individual plant uses had an average consensus of five and a maximum consensus of 15 out of 25. There were a number of rare and endangered species used as poisons or medicine that are endemic to Flora Europaea and found in Lukomir. Ten species (including subspecies) cited in our research have not previously been reported in the systematic ethnobotanical surveys of medicinal plant use in B&H: (Elymus repens (L.) Gould, Euphorbia myrsinites L., Jovibarba hirta (L.) Opiz, Lilium bosniacum (Beck) Fritsch, Matricaria matricarioides (Less.) Porter ex Britton, Phyllitis scolopendrium (L.) Newman, Rubus saxatilis L., Silene uniflora Roth ssp. glareosa (Jord.) Chater & Walters, Silene uniflora Roth ssp. prostrata (Gaudin) Chater & Walters, Smyrnium perfoliatum L.). New uses not reported in any of the aforementioned systematic surveys were cited for a total of 28 species. Thirteen percent of medicinal plants cited are endemic: Helleborus odorus Waldst. et Kit., Gentiana lutea L., Lilium bosniacum (Beck) Fritsch, Silene uniflora Roth ssp. glareosa (Jord.) Chater & Walters., Silene uniflora Roth ssp. prostrata (Gaudin) Chater & Walters, Salvia officinalis L., Jovibarba hirta (L.) Opiz, and Satureja montana L.

Conclusions

These results report on the cohesive tradition of medicinal plant use among healers in Lukomir, Bosnia and Herzegovina. This work facilitates the community’s development by facilitating local and international conversations about their traditional medicine and sharing insight for conservation in one of Europe’s most diverse endemic floristic regions, stewarded by one of Europe’s last traditional Highland peoples.
  相似文献   
93.
Duchenne muscular dystrophy is an X-linked disorder characterized by loss of dystrophin, a cytoskeletal protein that connects the actin cytoskeleton in skeletal muscle cells to extracellular matrix. Dystrophin binds to the cytoplasmic domain of the transmembrane glycoprotein β-dystroglycan (β-DG), which associates with cell surface α-dystroglycan (α-DG) that binds laminin in the extracellular matrix. β-DG can also associate with utrophin, and this differential association correlates with specific glycosylation changes on α-DG. Genetic modification of α-DG glycosylation can promote utrophin binding and rescue dystrophic phenotypes in mouse dystrophy models. We used high throughput screening with the plant lectin Wisteria floribunda agglutinin (WFA) to identify compounds that altered muscle cell surface glycosylation, with the goal of finding compounds that increase abundance of α-DG and associated sarcolemmal glycoproteins, increase utrophin usage, and increase laminin binding. We identified one compound, lobeline, from the Prestwick library of Food and Drug Administration-approved compounds that fulfilled these criteria, increasing WFA binding to C2C12 cells and to primary muscle cells from wild type and mdx mice. WFA binding and enhancement by lobeline required complex N-glycans but not O-mannose glycans that bind laminin. However, inhibiting complex N-glycan processing reduced laminin binding to muscle cell glycoproteins, although O-mannosylation was intact. Glycan analysis demonstrated a general increase in N-glycans on lobeline-treated cells rather than specific alterations in cell surface glycosylation, consistent with increased abundance of multiple sarcolemmal glycoproteins. This demonstrates the feasibility of high throughput screening with plant lectins to identify compounds that alter muscle cell glycosylation and identifies a novel role for N-glycans in regulating muscle cell function.  相似文献   
94.
Access to different environments may lead to inter-population behavioural changes within a species that allow populations to exploit their immediate environments. Elephant seals from Marion Island (MI) and King George Island (KGI) (Isla 25 de Mayo) forage in different oceanic environments and evidently employ different foraging strategies. This study elucidates some of the factors influencing the diving behaviour of male southern elephant seals from these populations tracked between 1999 and 2002. Mixed-effects models were used to determine the influence of bathymetry, population of origin, body length (as a proxy for size) and individual variation on the diving behaviour of adult male elephant seals from the two populations. Males from KGI and MI showed differences in all dive parameters. MI males dived deeper and longer (median: 652.0?m and 34.00?min) than KGI males (median: 359.1?m and 25.50?min). KGI males appeared to forage both benthically and pelagically while MI males in this study rarely reached depths close to the seafloor and appeared to forage pelagically. Model outputs indicate that males from the two populations showed substantial differences in their dive depths, even when foraging in areas of similar water depth. Whereas dive depths were not significantly influenced by the size of the animals, size played a significant role in dive durations, though this was also influenced by the population that elephant seals originated from. This study provides some support for inter-population differences in dive behaviour of male southern elephant seals.  相似文献   
95.
The measurement of carbon dioxide production rates as an indication of metabolic activity was applied to study biofilm development and response of Pseudomonas sp. biofilms to an environmental disturbance in the form of a moving air-liquid interface (i.e., shear). A differential response in biofilm cohesiveness was observed after bubble perturbation, and the biofilm layers were operationally defined as either shear-susceptible or non-shear-susceptible. Confocal laser scanning microscopy and image analysis showed a significant reduction in biofilm thickness and biomass after the removal of the shear-susceptible biofilm layer, as well as notable changes in the roughness coefficient and surface-to-biovolume ratio. These changes were accompanied by a 72% reduction of whole-biofilm CO2 production; however, the non-shear-susceptible region of the biofilm responded rapidly after the removal of the overlying cells and extracellular polymeric substances (EPS) along with the associated changes in nutrient and O2 flux, with CO2 production rates returning to preperturbation levels within 24 h. The adaptable nature and the ability of bacteria to respond to environmental conditions were further demonstrated by the outer shear-susceptible region of the biofilm; the average CO2 production rate of cells from this region increased within 0.25 h from 9.45 ± 5.40 fmol of CO2·cell−1·h−1 to 22.6 ± 7.58 fmol of CO2·cell−1·h−1 when cells were removed from the biofilm and maintained in suspension without an additional nutrient supply. These results also demonstrate the need for sufficient monitoring of biofilm recovery at the solid substratum if mechanical methods are used for biofouling control.Spatial differences in biofilm cohesiveness have been observed after the application of increased shear forces. Coufort et al. (8) subjected both aerobic and anaerobic biofilms, cultivated on ethanol or wastewater, to increased shear stress and found that the biofilm layer at the bulk liquid interface was removed by slight increases in shear rates (0.2 Pa), whereas the middle and base biofilm layers were able to resist removal when exposed to up to 2 Pa and 13 Pa, respectively (8). Total organic carbon (TOC) analyses indicated that the sensitive top layer of the biofilm contained approximately 60% of the total biofilm biomass while the remaining two layers each represented approximately 20%. In a follow-up study, biofilms grown under similar conditions exhibited comparable degrees of heterogeneity in the susceptibility of the various biofilm layers to shear and abrasion (9). It was also indicated that the basal biofilm layer contained active microorganisms, as characterized by oxygen uptake rates, but no details were provided on the methodology or time lapse after the removal of the less-cohesive upper biofilm layers.Spatial differentiation in metabolic activity in biofilms has also been noted. Most experimental strategies to determine biofilm activity have been centered on microscopy in combination with fluorescent reporter genes or probes that target various indicators of physiological activity in the cell. Several fluorescent stains have been applied previously, such as 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) (15) and acridine orange (27) as well as the commercially available BacLight viability kit (17). Reporter gene expression is another means to evaluate physiological activity in a biofilm. Alkaline phosphatase activity correlated well with oxygen penetration into the upper layers (30 μm) of 117- to 151-μm-thick biofilms (28).Although all of the above approaches have been shown to be effective, most suffer from inherent disadvantages (26), including incomplete penetration of fluorescent stains and the production of artifacts, and, perhaps most significantly, generally allow only end point analysis due to cellular toxicity. Reporter gene technologies may circumvent this problem but require prior genetic manipulation, and it is unknown what, if any, changes in cell physiology may occur as a result of expression of the reporter gene. The need for genetic manipulation further constrains analysis to pure culture studies.The basis for spatial heterogeneity in biofilm physiological activity is widely accepted, as previously reviewed (25, 26). Limited diffusion of nutrients and oxygen into the biofilm from the bulk liquid and waste products from a multilayered biofilm are among the simplest explanations since the absence of a complete exchange with the environment, in concert with microbial activity, leads to the formation of chemical gradients in the biofilm. The bacteria in the biofilm respond to the gradients, likely by altering gene expression patterns as determined by global regulators. The remarkable recalcitrance of biofilms toward many antimicrobials may in part be due to the insensitivity of dormant cells in the regions of the biofilm where limited diffusion reduces metabolic activity.The effect of air bubbles on biofilm stability has mostly been studied in a dental context, where biofilm removal is the goal. Gomez-Suarez et al. (11) utilized a single bubble to investigate the strength of bacterial cell adhesion to various surfaces (11). According to the authors, the probability of cell detachment due to the movement of an air bubble over an attached cell is determined by several factors, namely, collision efficiency, bubble-bacteria attachment efficiency, and the stability of the bubble-bacteria aggregate. For a bubble spanning the entire width of a flow chamber, the collision efficiency is expected to be equal to 1 although the velocity of the bubble may also influence the detachment efficiency since a rapidly moving bubble will result in a thicker liquid film surrounding the bubble, which in turn decreases the collision efficiency. Bacterium-substratum adhesion forces of ∼10−9 N were estimated, which is significantly smaller than the detachment force of a bubble moving over an attached cell (up to 10−7 N).Liquid flow in most environments—in nature, industry, and clinical or dental settings—typically shows much variation. It can be expected that microbial biofilms have evolved to manage this variability and even to utilize the resulting differences in flow to optimize activity (e.g., the prevention of excessive biomass accumulation for the maintenance of optimum gradients of nutrients and gases) or to relocate to more favorable environments.Furthermore, increased shear is a recognized strategy to remove unwanted microbial growth from surfaces; therefore, methods to measure the effect of shear on biofilms, including biofilm recovery after partial shear-induced removal, should contribute to our overall understanding of this important form of microbial existence. We developed an approach that measures CO2 production as an indication of biofilm activity in real time and combined this method with confocal laser scanning microscopy (CLSM) and cell yield measurements to study activity-structure relationships in biofilms. This approach is an extension of the one we described in 2009 (18) and enables us to comment on differences in metabolic activity of the whole biofilm versus that of the shear-susceptible biofilm region and to compare biofilm-derived planktonic cells with those growing in batch culture.  相似文献   
96.

Background

Malaria transmission rates in Africa can vary dramatically over the space of a few kilometres. This spatial heterogeneity reflects variation in vector mosquito habitat and presents an important obstacle to the efficient allocation of malaria control resources. Malaria control is further complicated by combinations of vector species that respond differently to control interventions. Recent modelling innovations make it possible to predict vector distributions and extrapolate malaria risk continentally, but these risk mapping efforts have not yet bridged the spatial gap to guide on-the-ground control efforts.

Methodology/Principal Findings

We used Maximum Entropy with purpose-built, high resolution land cover data and other environmental factors to model the spatial distributions of the three dominant malaria vector species in a 94,000 km2 region of east Africa. Remotely sensed land cover was necessary in each vector''s niche model. Seasonality of precipitation and maximum annual temperature also contributed to niche models for Anopheles arabiensis and An. funestus s.l. (AUC 0.989 and 0.991, respectively), but cold season precipitation and elevation were important for An. gambiae s.s. (AUC 0.997). Although these niche models appear highly accurate, the critical test is whether they improve predictions of malaria prevalence in human populations. Vector habitat within 1.5 km of community-based malaria prevalence measurements interacts with elevation to substantially improve predictions of Plasmodium falciparum prevalence in children. The inclusion of the mechanistic link between malaria prevalence and vector habitat greatly improves the precision and accuracy of prevalence predictions (r2 = 0.83 including vector habitat, or r2 = 0.50 without vector habitat). Predictions including vector habitat are unbiased (observations vs. model predictions of prevalence: slope = 1.02). Using this model, we generate a high resolution map of predicted malaria prevalence throughout the study region.

Conclusions/Significance

The interaction between mosquito niche space and microclimate along elevational gradients indicates worrisome potential for climate and land use changes to exacerbate malaria resurgence in the east African highlands. Nevertheless, it is possible to direct interventions precisely to ameliorate potential impacts.  相似文献   
97.
The mammalian GAS11 gene is a candidate tumor suppressor of unknown function that was previously identified as one of several genes upregulated upon growth arrest. Interestingly, although GAS11 homologs in Trypanosoma brucei (trypanin) and Chlamydomonas reinhardtii (PF2) are integral components of the flagellar axoneme and are necessary for regulating flagellar beat, the GAS11 gene was discovered based on its expression in cells that do not assemble a motile cilium. This suggests that GAS11 function might not be restricted to the cilium. To investigate this possibility, we generated GAS11-specific antibodies and demonstrate here that GAS11 is expressed in a variety of mammalian cells that lack a motile cilium. In COS7 cells, GAS11 is associated with the detergent-insoluble cytoskeleton and exhibits a juxtanuclear localization that overlaps with the pericentrosomal Golgi apparatus. This localization is dependent upon intact microtubules and is cell-cycle regulated, such that GAS11 is dispersed throughout the cytoplasm as cells progress through mitosis. GAS11 remains associated with Golgi fragments following depolymerization of cytoplasmic microtubules but is dispersed upon disruption of the Golgi with brefeldin A. These data suggest that GAS11 is associated with the Golgi apparatus. In support of this, recombinant GAS11 binds Golgi membranes in vitro. In growth-arrested mIMCD3 cells, GAS11 co-localizes with gamma-tubulin at the base of the primary cilium. The pericentrosomal Golgi apparatus and base of the cilium both represent convergence points for microtubule minus ends and correspond to sites where dynein regulation is required. The algal GAS11 homolog functions as part of a dynein regulatory complex (DRC) in the axoneme (Rupp and Porter. J Cell Biol 2003;162:47-57) and our findings suggest that components of this axonemal dynein regulatory system have been adapted in mammalian cells to participate in non-axonemal functions.  相似文献   
98.
Beetle luciferases (including those of the firefly) use the same luciferin substrate to naturally display light ranging in color from green (lambda(max) approximately 530 nm) to red (lambda(max) approximately 635 nm). In a recent communication, we reported (Branchini, B. R., Murtiashaw, M. H., Magyar, R. A., Portier, N. C., Ruggiero, M. C., and Stroh, J. G. (2002) J. Am. Chem. Soc. 124, 2112-2113) that the synthetic adenylate of firefly luciferin analogue D-5,5-dimethylluciferin was transformed into the emitter 5,5-dimethyloxyluciferin in bioluminescence reactions catalyzed by luciferases from Photinus pyralis and the click beetle Pyrophorus plagiophthalamus. 5,5-Dimethyloxyluciferin is constrained to exist in the keto form and fluoresces mainly in the red. However, bioluminescence spectra revealed that green light emission was produced by the firefly enzyme, and red light was observed with the click beetle protein. These results, augmented with steady-state kinetic studies, were taken as experimental support for mechanisms of firefly bioluminescence color that require only a single keto form of oxyluciferin. We report here the results of mutagenesis studies designed to determine the basis of the observed differences in bioluminescence color with the analogue adenylate. Mutants of P. pyralis luciferase putative active site residues Gly246 and Phe250, as well as corresponding click beetle residues Ala243 and Ser247 were constructed and characterized using bioluminescence emission spectroscopy and steady state kinetics with adenylate substrates. Based on an analysis of these and recently reported (Branchini, B. R., Southworth, T. L., Murtiashaw, M. H., Boije, H., and Fleet, S. E. (2003) Biochemistry 42, 10429-10436) data, we have developed an alternative mechanism of bioluminescence color. The basis of the mechanism is that luciferase modulates emission color by controlling the resonance-based charge delocalization of the anionic keto form of the oxyluciferin excited state.  相似文献   
99.
This first comprehensive study of the peripheral olfactory organ from a representative of the large and economically important order of teleost fishes, the Perciformes, shows a compact structure with olfactory sensory neurons distributed widely throughout the olfactory chamber. The spatial organization of the nasal cavity in the bottom-dwelling round goby (Gobiidae, Neogobius melanostomus) was examined using impression material injection, immunocytochemistry, and transmission electron microscopy. The olfactory chamber contains a single olfactory lamella; prominent dorsocaudal lachrymal and ethmoidal accessory nasal sacs are situated ventrocaudal to the chamber. The location of the olfactory mucosa within the olfactory chamber is novel for teleost fish, as it extends beyond the ventral surface to the lateral and dorsal regions. Microvillar olfactory sensory neurons and ciliated olfactory sensory neurons were identified by transmission electron microscopy and the spatial distribution of these two cell types was assessed through immunocytochemistry against olfactory receptor coupled G-proteins. Both G(alphaolf)-immunoreactive ciliated olfactory sensory neurons and the G(alphao)-immunoreactive microvillar form were located throughout the olfactory epithelium. Ciliated crypt cells were G(alphao) immunoreactive and were found throughout the olfactory epithelium of some specimens. The widespread occurrence of olfactory sensory neurons in the olfactory chamber supports the idea that olfactory signaling is important to the survival of the round goby. The prominence of the lachrymal and ethmoidal accessory nasal sacs indicates the capacity to regulate the flow of odorant molecules over the sensory surface of the olfactory sensory neurons, possibly through a pump-like mechanism driven by opercular activity associated with gill ventilation.  相似文献   
100.
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