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71.
When the body is ailing the mind is soon impaired. Good health practices contribute to longer and better life. A balanced life of work-rest-play is necessary to human health.Psychosocial stresses at any period of life may impair morale and productivity and increase the likelihood of physical or mental disease. Bereavement, separation, divorce, loss of friendship, retirement, loss of self-esteem and symbolic losses contribute significantly to mental and physical ill health. Social and psychological support systems are vital to mental health maintenance.Mature persons evolve principles, values, moral and ethical tenets, philosophic and religious ideals and special codes of conduct to give meaning to their lives. The basic needs of survival and procreation must be integrated with moral precepts relating to interindividual behavior so as to give a person a feeling of self-worth, which is an indispensable element in mental health.  相似文献   
72.
Of the various protozoal diseases for which vaccines are under development, cutaneous leishmaniasis (CL), in spite o f its chronic nature, may provide the best candidate for success. Stringent experimental models are available for both new and old world CL, human studies have been conducted for several years, and there is now considerable experience in using both attenuated and killed vaccines. In this article, Chuck Greenblatt discusses this experience, showing how it has led to current WHO-TDR plans for field trials of killed vaccines followed by virulent challenge (as used in Iran in the practice of 'leishmanization').  相似文献   
73.
74.
Defining protein complexes is critical to virtually all aspects of cell biology. Two recent affinity purification/mass spectrometry studies in Saccharomyces cerevisiae have vastly increased the available protein interaction data. The practical utility of such high throughput interaction sets, however, is substantially decreased by the presence of false positives. Here we created a novel probabilistic metric that takes advantage of the high density of these data, including both the presence and absence of individual associations, to provide a measure of the relative confidence of each potential protein-protein interaction. This analysis largely overcomes the noise inherent in high throughput immunoprecipitation experiments. For example, of the 12,122 binary interactions in the general repository of interaction data (BioGRID) derived from these two studies, we marked 7504 as being of substantially lower confidence. Additionally, applying our metric and a stringent cutoff we identified a set of 9074 interactions (including 4456 that were not among the 12,122 interactions) with accuracy comparable to that of conventional small scale methodologies. Finally we organized proteins into coherent multisubunit complexes using hierarchical clustering. This work thus provides a highly accurate physical interaction map of yeast in a format that is readily accessible to the biological community.  相似文献   
75.
76.
Model organisms such as yeast, fly, and worm have played a defining role in the study of many biological systems. A significant challenge remains in translating this information to humans. Of critical importance is the ability to differentiate those components where knowledge of function and interactions may be reliably inferred from those that represent lineage‐specific innovations. To address this challenge, we use chromatin modification (CM) as a model system for exploring the evolutionary properties of their components in the context of their known functions and interactions. Collating previously identified components of CM from yeast, worm, fly, and human, we identified a “core” set of 50 CM genes displaying consistent orthologous relationships that likely retain their interactions and functions across taxa. In addition, we catalog many components that demonstrate lineage specific expansions and losses, highlighting much duplication within vertebrates that may reflect an expanded repertoire of regulatory mechanisms. Placed in the context of a high‐quality protein–protein interaction network, we find, contrary to existing views of evolutionary modularity, that CM complex components display a mosaic of evolutionary histories: a core set of highly conserved genes, together with sets displaying lineage specific innovations. Although focused on CM, this study provides a template for differentiating those genes which are likely to retain their functions and interactions across species. As such, in addition to informing on the evolution of CM as a system, this study provides a set of comparative genomic approaches that can be generally applied to any biological systems. Proteins 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
77.
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   
78.

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   
79.

Background

The natural history of HSV-2 infection and role of HSV-2 reactivations in HIV disease progression are unclear.

Methods

Clinical symptoms of active HSV-2 infection were used to classify 1,938 HIV/HSV-2 co-infected participants of the Women''s Interagency HIV Study (WIHS) into groups of varying degree of HSV-2 clinical activity. Differences in plasma HIV RNA and CD4+ T cell counts between groups were explored longitudinally across three study visits and cross-sectionally at the last study visit.

Results

A dose dependent association between markers of HIV disease progression and degree of HSV-2 clinical activity was observed. In multivariate analyses after adjusting for baseline CD4+ T cell levels, active HSV-2 infection with frequent symptomatic reactivations was associated with 21% to 32% increase in the probability of detectable plasma HIV RNA (trend p = 0.004), an average of 0.27 to 0.29 log10 copies/ml higher plasma HIV RNA on a continuous scale (trend p<0.001) and 51 to 101 reduced CD4+ T cells/mm3 over time compared to asymptomatic HSV-2 infection (trend p<0.001).

Conclusions

HIV induced CD4+ T cell loss was associated with frequent symptomatic HSV-2 reactivations. However, effect of HSV-2 reactivations on HIV disease progression markers in this population was modest and appears to be dependent on the frequency and severity of reactivations. Further studies will be necessary to determine whether HSV-2 reactivations contribute to acceleration of HIV disease progression.  相似文献   
80.
We have previously isolated sphericase (Sph), an extracellular mesophilic serine protease produced by Bacillus sphaericus. The Sph amino acid sequence is highly homologous to two cold-adapted subtilisins from Antarctic bacilli S39 and S41 (76% and 74% identity, respectively). Sph is calcium-dependent, 310 amino acid residues long and has optimal activity at pH 10.0. S41 and S39 have not as yet been structurally analysed.In the present work, we determined the crystal structure of Sph by the Eu/multiwavelength anomalous diffraction method. The structure was extended to 0.93A resolution and refined to a crystallographic R-factor of 9.7%. The final model included all 310 amino acid residues, one disulfide bond, 679 water molecules and five calcium ions. Although Sph is a mesophilic subtilisin, its amino acid sequence is similar to that of the psychrophilic subtilisins, which suggests that the crystal structure of these subtilisins is very similar.The presence of five calcium ions bound to a subtilisin molecule, as found here for Sph, has not been reported for the subtilisin superfamily. None of these calcium-binding sites correlates with the well-known high-affinity calcium-binding site (site I or site A), and only one site has been described previously. This calcium-binding pattern suggests that a reduction in the flexibility of the surface loops of Sph by calcium binding may be responsible for its adaptation to mesophilic organisms.  相似文献   
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