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41.

Background

Changing lifestyles have recently caused a severe reduction of the gathering of wild food plants. Knowledge about wild food plants and the local environment becomes lost when plants are no longer gathered. In Central Europe popular scientific publications have tried to counter this trend. However, detailed and systematic scientific investigations in distinct regions are needed to understand and preserve wild food uses. This study aims to contribute to these investigations.

Methods

Research was conducted in the hill country east of Graz, Styria, in Austria. Fifteen farmers, most using organic methods, were interviewed in two distinct field research periods between July and November 2008. Data gathering was realized through freelisting and subsequent semi-structured interviews. The culinary use value (CUV) was developed to quantify the culinary importance of plant species. Hierarchical cluster analysis was performed on gathering and use variables to identify culture-specific logical entities of plants. The study presented was conducted within the framework of the master's thesis about wild plant gathering of the first author. Solely data on gathered wild food species is presented here.

Results

Thirty-nine wild food plant and mushroom species were identified as being gathered, whereas 11 species were mentioned by at least 40 percent of the respondents. Fruits and mushrooms are listed frequently, while wild leafy vegetables are gathered rarely. Wild foods are mainly eaten boiled, fried or raw. Three main clusters of wild gathered food species were identified: leaves (used in salads and soups), mushrooms (used in diverse ways) and fruits (eaten raw, with milk (products) or as a jam).

Conclusions

Knowledge about gathering and use of some wild food species is common among farmers in the hill country east of Graz. However, most uses are known by few farmers only. The CUV facilitates the evaluation of the culinary importance of species and makes comparisons between regions and over time possible. The classification following gathering and use variables can be used to better understand how people classify the elements of their environment. The findings of this study add to discussions about food heritage, popularized by organizations like Slow Food, and bear significant potential for organic farmers.  相似文献   
42.
Cytochrome c oxidase subunit II (COII), encoded by the mitochondrial genome, exhibits one of the most heterogeneous rates of amino acid replacement among placental mammals. Moreover, it has been demonstrated that cytochrome c oxidase has undergone a structural change in higher primates which has altered its physical interaction with cytochrome c. We collected a large data set of COII sequences from several orders of mammals with emphasis on primates, rodents, and artiodactyls. Using phylogenetic hypotheses based on data independent of the COII gene, we demonstrated that an increased number of amino acid replacements are concentrated among higher primates. Incorporating approximate divergence dates derived from the fossil record, we find that most of the change occurred independently along the New World monkey lineage and in a rapid burst before apes and Old World monkeys diverged. There is some evidence that Old World monkeys have undergone a faster rate of nonsynonymous substitution than have apes. Rates of substitution at four-fold degenerate sites in primates are relatively homogeneous, indicating that the rate heterogeneity is restricted to nondegenerate sites. Excluding the rate acceleration mentioned above, primates, rodents, and artiodactyls have remarkably similar nonsynonymous replacement rates. A different pattern is observed for transversions at four-fold degenerate sites, for which rodents exhibit a higher rate of replacement than do primates and artiodactyls. Finally, we hypothesize specific amino acid replacements which may account for much of the structural difference in cytochrome c oxidase between higher primates and other mammals.   相似文献   
43.
Immobilization of photobacteria in the cryogel of polyvinyl alcohol (PVA) was carried out. Immobilization was found to result in increased intensity and stability of bioluminescence. The elements determining the stability of bioluminescence were investigated. Selection of the strain was found to be of the highest importance. Among immobilized cells, Photobacterium phosphoreum exhibited the most intense and prolonged light emission, while Vibrio harveyi showed the least one. The technological procedures for cryogenic immobilization of photobacteria were determined. The role of the environment of gel formation in the preservation of the bioluminescence activity was determined. In the gels formed in rich medium for submerged cultivation of photobacteria, almost 100% luminescence activity was preserved, while light emission was considerably prolonged. Bioluminescence intensity of the preparations was shown to depend significantly on pH of the incubation medium. The pH shift to acidic values during prolonged incubation of immobilized cells was shown to be one of the factors of bioluminescence quenching. The stress effects of cryogenic immobilization were found to have an insignificant effect on the temperature profile of bioluminescence. Decreased reduction rate of the luciferase flavin substrate was shown to be a possible reason for bioluminescence quenching.  相似文献   
44.
Experiments were performed to localize the hepatic microsomal enzymes of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol biosynthesis to the cytoplasmic or lumenal surface of microsomal vesicles. Greater than 90 percent of the activities of fatty acid-CoA ligase (EC 6.2.1.3), sn-glycerol 3-phosphate acyltransferase (EC 2.3.1.15), lysophosphatidic acid acyltransferase, diacylglycerol acyltransferase (EC 2.3.1.20), diacylglycerol cholinephosphotransferase (EC 2.7.8.2), and diacylglycerol ethanolaminephosphotransferase (EC 2.7.8.1) was inactivated by proteolysis of intact microsomal vesicles. The phosphatidic acid phosphatase (EC 3.1.3.4) was not inactivated by any of the protease tested. Under conditions employed, <5 percent of the luminal mannose-6-phosphatase (EC 3.1.3.9) activity was lost. After microsomal integrity was disrupted with detergents, protease treatment resulted in a loss of >74 percent of the mannose-6-phosphatase activity. The latency of the mannose-6-phosphatase activity was not affected by protease treatment. Mannose-6-phosphatase latency was not decreased by the presence of the assay components of several of the lipid biosynthetic activities, indicating that those components did not disrupt the microsomal vesicles. None of the lipid biosynthetic activities appeared latent. The presence of a protease-sensitive component of these biosynthetic activities on the cytoplasmic surface of microsomal vesicles, and the absence of latency for any of these biosynthetic activities suggest that the biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol occurs asymmetrically on the cytoplasmic surface of the endoplasmic reticulum. The location of biosynthetic activities within the transverse plane of the endoplasmic reticulum is of particular interest for enzymes whose products may be either secreted or retained within the cell. Phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol account for the vast majority of hepatic glycerolipid biosynthesis. The phospholipids are utilized for hepatic membrane biogenesis and for the formation of lipoproteins, and the triacylglycerols are incorporated into lipoproteins or accumulate within the hepatocyte in certain disease states (14). The enzymes responsible for the biosynthesis of these glycerolipids (Scheme I) from fatty acids and glycerol-3P have all been localized to the microsomal subcellular fraction (12, 16, 29, 30). Microsomes are derived from the endoplasmic reticulum and are sealed vesicles which maintain proper sidedness. (11, 22). The external surface of these vesicles corresponds to the cytoplasmic surface of the endoplasmic reticulum. Macromolecules destined for secretion must pass into the lumen of the endoplasmic reticulum (5, 23). Uncharged molecules of up to approximately 600 daltons are able to enter the lumen of rat liver microsomes, but macromolecules and charged molecules of low molecular weight do not cross the vesicle membrane (10, 11). Because proteases neither cross the microsomal membrane nor destroy the permeability barrier of the microsomal vesicles, only the enzymes and proteins located on the cytoplasmic surface of microsomal vesicles are susceptible to proteolysis unless membrane integrity is disrupted (10, 11). By use of this approach, several enzymes and proteins have been localized in the transverse plane of microsomal membranes (11). With the possible exception of cytochrome P 450, all of the enzymes and proteins investigated were localized asymmetrically by the proteolysis technique (11). By studies of this type, as well as by product localization, glucose-6-phosphate (EC 3.1.3.9) has been localized to the luminal surface of microsomal vesicles (11) and of the endoplasmic reticulum (18, 19). All microsomal vesicles contain glucose-6-phosphatase (18, 19) which can effectively utilize mannose-6-P as a substrate, provided the permeability barrier of the vesicles has been disrupted to allow the substrate access to the active site located on the lumenal surface (4). An exact correspondence between mannose- 6-phosphate activity and membrane permeability to EDTA has been established (4). The latency of mannose-6-phosphatase activity provides a quantitative index of microsomal integrity (4.) Few of the microsomal enzymes in the synthesis of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol have been solubilized and/or purified, and little is known about the topography of these enzymes in the transverse or lateral planes of the endoplasmic reticulum. An asymmetric location of these biosynthetic enzymes on the cytoplasmic or lumenal surface of microsomal vesicles may provide a mechanism for regulation of the glycerolipids to be retained or secreted by the cell, and for the biogenesis of asymmetric phospholipid bilayers. In this paper, we report investigations on the localization of all seven microsomal enzymes (Scheme I) in the biosynthesis of triacylglycerol, phosphatidylcholine, and phosphatidylethanolamine, using the protease technique with mannose-6-phosphatase serving as luminal control activity. The latency of these lipid biosynthetic enzymes was also investigated, using the latency of mannose-6-phosphatase as an index of microsomal integrity.  相似文献   
45.
Rapamycin at high doses (2–10 mg/kg body weight) inhibits mammalian target of rapamycin complex 1 (mTORC1) and protein synthesis in mice. In contrast, low doses of rapamycin (10 μg/kg) increase mTORC1 activity and protein synthesis in skeletal muscle. Similar changes are found with SLF (synthetic ligand for FKBP12, which does not inhibit mTORC1) and in mice with a skeletal muscle-specific FKBP12 deficiency. These interventions also increase Ca2+ influx to enhance refilling of sarcoplasmic reticulum Ca2+ stores, slow muscle fatigue, and increase running endurance without negatively impacting cardiac function. FKBP12 deficiency or longer treatments with low dose rapamycin or SLF increase the percentage of type I fibers, further adding to fatigue resistance. We demonstrate that FKBP12 and its ligands impact multiple aspects of muscle function.  相似文献   
46.
The cellular traffic of haem during the development of the human malaria parasite Plasmodium falciparum, through the stages R (ring), T (trophozoite) and S (schizonts), was investigated within RBC (red blood cells). When Plasmodium cultures were incubated with a fluorescent haem analogue, ZnPPIX (Zn protoporphyrin IX) the probe was seen at the cytoplasm (R stage), and the vesicle‐like structure distribution pattern was more evident at T and S stages. The temporal sequence of ZnPPIX uptake byP. falciparum‐infected erythrocytes shows that at R and S stages, a time‐increase acquisition of the porphyrin reaches the maximum fluorescence distribution after 60 min; in contrast, at the T stage, the maximum occurs after 120 min of ZnPPIX uptake. The difference in time‐increase acquisition of the porphyrin is in agreement with a maximum activity of haem uptake at the T stage. To gain insights into haem metabolism, recombinant PfHO (P. falciparum haem oxygenase) was expressed, and the conversion of haem into BV (biliverdin) was detected. These findings point out that, in addition to haemozoin formation, the malaria parasite P. falciparum has evolved two distinct mechanisms for dealing with haem toxicity, namely, the uptake of haem into a cellular compartment where haemozoin is formed and HO activity. However, the low Plasmodium HO activity detected reveals that the enzyme appears to be a very inefficient way to scavenge the haem compared with the Plasmodium ability to uptake the haem analogue ZnPPIX and delivering it to the food vacuole.  相似文献   
47.
A qualitative and quantitative electron microscopic study was performed on rat adipocytes during stimulation of lipolysis by various agents. Scanning electron microscopy of control cells revealed a spherical cell with a textured glycocalyx surface exhibiting small irregular projections. Globular surface evaginations or protrusions measuring 8-18 μM in diameter were seen on cell hemispheres, and there was an average of one protrusion for every two hemispheres examined. Distribution analysis showed that 60 percent of the hemispheres had no protrusions, and 25, 10, and 5 percent of the hemispheres had one, two or three protrusions, respectively. Thin-section and freeze- fracture electron microscopy of the protrusions showed a small triglyceride droplet surrounded by a thin cytoplasmic rim that was continuous with the main cytoplasmic matrix. The glycocalyx coating and plasma membrane extended from the cell surface onto, and over, the protrusion. Scanning microscopy of cells stimulated by lipolytic agents, including epinephrine, adrenocorticotropic hormone, theophylline, and dibutyryl cyclic AMP, revealed a dose-dependent increase in the number of protrusions per cell hemisphere. Maximal concentrations of lipolytic hormones cuase an average 2.5-fold increase in the number of protrusions per hemisphere without changing the average size of the protrusions. Only 40 percent of the stimulated cell hemispheres exhibited no protrusions; over 15 percent of the cells contained three or more; and a number of the protrusions were multilobulate. Insulin prevented the increase in the number of protrusions and the change in distribution caused by the lipolytic hormones but did not prevent the increase caused by theophylline and dibutryl cyclic AMP. The data suggest that the protrusions are a structural feature of the cell and may be related to the lypolytic pathway. These observations may help explain some of the discrepant biochemical data relating to hormonal stimulation of lipolysis.  相似文献   
48.
49.

Background

Except during a 1-year period when BCG vaccine was not routinely administered, annual coverage of infants with Bacillus Calmette-Guérin (BCG) in Kazakhstan since 2002 has exceeded 95%. BCG preparations from different sources (Japan, Serbia, and Russia) or none were used exclusively in comparable 7-month time-frames, September through March, in 4 successive years beginning in 2002. Our objective was to assess relative effectiveness of BCG immunization.

Methods/Findings

We compared outcomes of birth cohorts from the 4 time-frames retrospectively. Three cohorts received vaccine from one of three manufacturers exclusively, and one cohort was not vaccinated. Cohorts were followed for 3 years for notifications of clinical TB and of culture-confirmed TB, and for 21 months for TB meningitis notifications. Prevention effectiveness based on relative risk of TB incidence was calculated for each vaccinated cohort compared to the non-vaccinated cohort.Although there were differences in prevention effectiveness observed among the three BCG vaccines, all were protective. The Japanese vaccine (currently used in Kazakhstan), the Serbian vaccine, and the Russian vaccine respectively were 69%, 43%, and 22% effective with respect to clinical TB notifications, and 92%, 82%, and 51% effective with respect to culture confirmed TB. All three vaccines were >70% effective with respect to TB meningitis.

Limitations

Potential limitations included considerations that 1) the methodology used was retrospective, 2) multiple risk factors could have varied between cohorts and affected prevention effectiveness measures, 3) most cases were clinically diagnosed, and TB culture-positive case numbers and TB meningitis case numbers were sparse, and 4) small variations in reported population TB burden could have affected relative risk of exposure for cohorts.

Conclusions/Significance

All three BCG vaccines evaluated were protective against TB, and prevention effectiveness varied by manufacturer. When setting national immunization policy, consideration should be given to prevention effectiveness of BCG preparations.  相似文献   
50.
Mice with a knock-in mutation (Y524S) in the type I ryanodine receptor (Ryr1), a mutation analogous to the Y522S mutation that is associated with malignant hyperthermia in humans, die when exposed to short periods of temperature elevation (≥37 °C). We show here that treatment with 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) prevents this heat-induced sudden death in this mouse model. The protection by AICAR is independent of AMP-activated protein kinase (AMPK) activation and results from a newly identified action of the compound on mutant Ryr1 to reduce Ca(2+) leak from the sarcoplasmic reticulum to the sarcoplasm. AICAR thus prevents Ca(2+)-dependent increases in the amount of both reactive oxygen species (ROS) and reactive nitrogen species (RNS) that act to further increase resting Ca(2+) concentrations. If unchecked, the temperature-driven increases in resting Ca(2+) concentrations and the amounts of ROS and RNS create an amplifying cycle that ultimately triggers sustained muscle contractions, rhabdomyolysis and death. Although antioxidants are effective in reducing this cycle in vitro, only AICAR prevents heat-induced death in vivo. Our findings suggest that AICAR is probably effective in prophylactic treatment of humans with enhanced susceptibility to exercise- and/or heat-induced sudden death associated with RYR1 mutations.  相似文献   
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