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31.
The effects of diet on inflammation: emphasis on the metabolic syndrome.   总被引:3,自引:0,他引:3  
Reducing the incidence of coronary heart disease with diet is possible. The main dietary strategies include adequate omega-3 fatty acids intake, reduction of saturated and trans-fats, and consumption of a diet high in fruits, vegetables, nuts, and whole grains and low in refined grains. Each of these strategies may be associated with lower generation of inflammation. This review examines the epidemiologic and clinical evidence concerning diet and inflammation. Dietary patterns high in refined starches, sugar, and saturated and trans-fatty acids, poor in natural antioxidants and fiber from fruits, vegetables, and whole grains, and poor in omega-3 fatty acids may cause an activation of the innate immune system, most likely by an excessive production of proinflammatory cytokines associated with a reduced production of anti-inflammatory cytokines. The whole diet approach seems particularly promising to reduce the inflammation associated with the metabolic syndrome. The choice of healthy sources of carbohydrate, fat, and protein, associated with regular physical activity and avoidance of smoking, is critical to fighting the war against chronic disease. Western dietary patterns warm up inflammation, while prudent dietary patterns cool it down.  相似文献   
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We studied NK cell function in eight patients with pathological hyperprolactinemia by measuring51Cr release by K562 cells exposed to their mononuclear cells and found it decreased compared to normal controls (P<0.01). Bromocriptine (BrC) treatment corrected NK function but also made it more efficient at 12:1 than at 25:1 or 50:1 effector:target ratios (ANOVA;P=0.01). The study of NK cell function in agarose revealed that its decrease in hyperprolactinemia is due to their low active binding to target cells, active killing, and recycling capacity. BrC tended to correct them but also increased recycling capacity to levels higher than those of controls (P<0.05). Sequential studies in three hyperprolactinemic patients before and after BrC showed correction of NK function within 1 week but its increased efficiency at the 12:1 effector:target ratio required 8 weeks. We conclude that hyperprolactinemia decreases NK cell function. BrC corrects this by decreasing prolactin levels but also makes NK function more efficient by increasing the capacity of NK cells to recycle after killing.  相似文献   
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Hyperexcitability of the motor system has been reported in Parkinson's disease (PD). We evaluate how cutaneous afferents modulate motor excitability in PD patients and whether abnormal modulation is correlated to parkinsonian symptoms. Digital stimulation causes abnormal enhancement of motor responses in patients. This effect may be one of the features of motor hyperexcitability in PD. Cutaneomotor hyperexcitability correlates with clinical scores, suggesting that abnormal processing of cutaneous inputs might contribute to the pathogenesis of parkinsonian symptoms.  相似文献   
36.
The CD16: ζ: γ receptor complex allows natural killer (NK) cells to recognize and eliminate antibody-coated target cells. Whereas the ectodomain of CD16 is the receptor for Fcγ domains of immunoglobulins, disulfide-linked homo- and heterodimers composed of ζ and γ are required for the cell surface expression, and signal transduction properties of the complex. Engagement of CD16 activates the tyrosine kinase pathway, which induces the tyrosine phosphorylation of several substrates, including the ζ subunit and the phospholipase C γ-1 and γ-2 isoforms. Here we show that CD 16 stimulation of either peripheral blood NK cells, leukemic NK cells, or Jurkat transformants expressing a CD16:ζ:γ receptor complex, results in the tyrosine phosphorylation of a 70 kDa ζ-associated protein (pp70). Similarly, a 70-kDa ζ-associated phosphoprotein in T cells has been shown to be a tyrosine kinase (ZAP-70). Peptide mapping analysis indicates that the 70-kDa ζ-associated phosphoproteins from T cells and NK cells are structurally indistinguishable. We conclude that the CD16:ζ:γ complex may use a ZAP-70-related non-receptor tyrosine kinase, in the CD16 signaling cascade leading to NK cell activation.  相似文献   
37.
A vaccination trial, performed on 86 3-month-old infants, has shown that the ability of the RIT 4237 live attenuated rotavirus strain to induce seroconversion is dramatically reduced when administered with live poliovirus vaccine. In a subsequent trial performed on 93 infants the attempt to overcome the poliovirus interference by administering two doses of associated vaccines was unsuccessful. No interference by the RIT 4237 strain on live attenuated polioviruses was observed.  相似文献   
38.
Inability to detect vessel overlap and vascular loops can compromise the interpretation of magnetic resonance angiograms. A data-adaptive ray tracing (DART) technique was developed to produce the appropriate variations in signal intensity at points of vessel overlap in order to simulate the standard angiographic representation of vessels. In this technique a threshold is utilized to identify vessels in the image slices composing a 3D angiographic data set. A mask, which defines regions slightly larger than the vessel boundaries, is obtained by blurring the vessel information surviving the initial threshold. This mask is converted to binary form prior to multiplication by the original angiographic data set. Following application of an additional threshold to the masked data, line integrals through the regions defined by the mask are performed to obtain an angiographic signal proportional to the integrated vessel signal as in conventional angiography. This integrated reprojection is then uniquely combined with a maximum intensity pixel (MIP) reprojection to produce the final DART image. The application of the DART technique to 2D time-of-flight and 3D phase-contrast angiograms successfully enabled the identification of over-lapping vessels and vascular loops. DART was also found to produce less vessel narrowing than the MIP technique.  相似文献   
39.
The isoleucyl-tRNA synthetase (ileS) gene was sequenced in toto from 9 and in part from 31 Staphylococcus aureus strains with various degrees of susceptibility to mupirocin. All strains for which the mupirocin MIC was greater than 8 microg/ml contained point mutations affecting the Rossman fold via Val-to-Phe changes at either residue 588 (V588F) or residue 631 (V631F). The importance of the V588F mutation was confirmed by an allele-specific PCR survey of 32 additional strains. Additional mutations of uncertain significance were found in residues clustered on the surface of the IleS protein.  相似文献   
40.
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