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There is evidence that there is an association between chronic fatigue syndrome, a condition of unknown aetiology, and essential fatty acids. This evidence is based on the actions of essential fatty acids, the results of proton neurospectroscopy studies, and essential fatty acid trial data. A series of patients with chronic fatigue syndrome were treated solely with a high-eicosapentaenoic acid-containing essential fatty acid supplement. All showed improvement in their symptomatology within eight to 12 weeks. These results, which are consistent with a recent detailed report of cerebral and clinical changes associated with a high intake of eicosapentaenoic acid, suggest that this n-3 highly unsaturated fatty acid may offer the hope of effective treatment for at least some patients with chronic fatigue syndrome.  相似文献   
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Phytochemical investigation of Datura quercifolia (Solanaceae) plant yielded a new datura lactone, 1β,5,12-trihydroxy-6,7,24,25-diepoxy-20S,22R with-2-enolide (1), along with two known compounds, 2 and 3. The structure of 1 was established on the basis of spectral analysis, as well as by its chemical transformation into known datura lactones. These compounds have been evaluated for immunomodulatory activity by observing their effect on antibody production, T-cell and B-cell activation, and cytokine production from splenocytes. Compound 2 was found to be the most promising immunostimulator in the present study.  相似文献   
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The identification of proteins in proteomics experiments is usually based on mass information derived from tandem mass spectrometry data. To improve the performance of the identification algorithms, additional information available in the fragment peak intensity patterns has been shown to be useful. In this study, we consider the effect of iTRAQ labeling on the fragment peak intensity patterns of singly charged peptides from MALDI tandem MS data. The presence of an iTRAQ-modified basic group on the N-terminus leads to a more pronounced set of b-ion peaks and distinct changes in the abundance of specific peptide types. We performed a simple intensity prediction by using a decision-tree machine learning approach and were able to show that the relative ion abundance in a spectrum can be correctly predicted and distinguished from closely related sequences. This information will be useful for the development of improved method-specific intensity-based protein identification algorithms.  相似文献   
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Background

The gold standard for diagnosis of typhoid fever is blood culture (BC). Because blood culture is often not available in impoverished settings it would be helpful to have alternative diagnostic approaches. We therefore investigated the usefulness of clinical signs, WHO case definition and Widal test for the diagnosis of typhoid fever.

Methodology/Principal Findings

Participants with a body temperature ≥37.5°C or a history of fever were enrolled over 17 to 22 months in three hospitals on Pemba Island, Tanzania. Clinical signs and symptoms of participants upon presentation as well as blood and serum for BC and Widal testing were collected. Clinical signs and symptoms of typhoid fever cases were compared to other cases of invasive bacterial diseases and BC negative participants. The relationship of typhoid fever cases with rainfall, temperature, and religious festivals was explored. The performance of the WHO case definitions for suspected and probable typhoid fever and a local cut off titre for the Widal test was assessed. 79 of 2209 participants had invasive bacterial disease. 46 isolates were identified as typhoid fever. Apart from a longer duration of fever prior to admission clinical signs and symptoms were not significantly different among patients with typhoid fever than from other febrile patients. We did not detect any significant seasonal patterns nor correlation with rainfall or festivals. The sensitivity and specificity of the WHO case definition for suspected and probable typhoid fever were 82.6% and 41.3% and 36.3 and 99.7% respectively. Sensitivity and specificity of the Widal test was 47.8% and 99.4 both forfor O-agglutinin and H- agglutinin at a cut-off titre of 1∶80.

Conclusions/Significance

Typhoid fever prevalence rates on Pemba are high and its clinical signs and symptoms are non-specific. The sensitivity of the Widal test is low and the WHO case definition performed better than the Widal test.  相似文献   
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The mammalian HIRA/UBN1/CABIN1/ASF1a (HUCA) histone chaperone complex deposits the histone H3 variant H3.3 into chromatin and is linked to gene activation, repression, and chromatin assembly in diverse cell contexts. We recently reported that a short N-terminal fragment of UBN1 containing amino acids 1-175 is necessary and sufficient for interaction with the WD repeats of HIRA and attributed this interaction to a region from residues 120-175 that is highly conserved with the yeast ortholog Hpc2 and so termed the HRD for Hpc2-related domain. In this report, through a more comprehensive and refined biochemical and mutational analysis, we identify a smaller and more moderately conserved region within residues 41-77 of UBN1, which we term the NHRD, that is essential for interaction with the HIRA WD repeats; we further demonstrate that the HRD is dispensable for this interaction. We employ analytical ultracentrifugation studies to demonstrate that the NHRD of UBN1 and the WD repeats of HIRA form a tight 1:1 complex with a dissociation constant in the nanomolar range. Mutagenesis experiments identify several key residues in the NHRD that are required for interaction with the HIRA WD repeat domain, stability of the HUCA complex in vitro and in vivo, and changes in chromatin organization in primary human cells. Together, these studies implicate the NHRD domain of UBN1 as being an essential region for HIRA interaction and chromatin organization by the HUCA complex.  相似文献   
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