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N-acetylmuramyl-L-alanine amidase (NAMLAA) specifically degrades peptidoglycan, which is a major component of bacterial cell walls with strong inflammatory properties. For instance, peptidoglycan is capable of stimulating peripheral blood cells to release pro-inflammatory cytokines and is capable of inducing chronic arthritis in an animal model. In a previous study we found that degradation of peptidoglycan by purified NAMLAA reduced its inflammatory effects. To determine where NAMLAA is located in tissues, monoclonal antibodies against purified NAMLAA were produced for use in immunohistochemistry, immunoelectron microscopy, flow cytometric analysis, and Western blotting. The immunohistochemical studies showed NAMLAA-positive cells in human spleen, liver, arthritic synovial tissues, and lymph nodes. In flow cytometric studies of blood and bone marrow, neutrophilic and eosinophilic granulocytes proved to be positive. Monocytes were negative, although they do contain lysozyme, the other important peptidoglycan-degrading enzyme. However, mature macrophages obtained by bronchoalveolar lavage and subsequent selection based on autofluorescence did possess NAMLAA. In immunocytochemical staining of blood smears, thrombocytes were also positive for NAMLAA. Western blot analysis and immunoelectron microscopy of neutrophils and eosinophils showed that NAMLAA is located in azurophilic granules of neutrophils and in secretory vesicles and crystalloid-containing granules of eosinophils. Flow cytometric analysis of blood and bone marrow from different French-American-British-classified acute myeloid leukemia (AML) patients showed that AML-M2 myeloblasts were the first in the granulocyte maturation lineage that were positive for NAMLAA. The more immature AML, such as AML-M0 and AML-M1, did not express NAMLAA. CD15- and CD13-negative megakaryoblasts, corresponding to AML-M7, were also positive for NAMLAA. The expression pattern of NAMLAA in the myeloid lineage suggests that the monoclonal antibody AAA4, recognizing NAMLAA, is useful for discrimination between AML in the monocyte lineage and in the granulocyte lineage.  相似文献   
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This study examined the influence of a generalized physical fitness training program on manual material handling (MMH) capability. Thirteen healthy women trained for 14 weeks, performing progressive resistance training three days per week and running with interval training two days per week. Subjects attended 85 +/- 6% of the sessions. Compared to values obtained before training, subjects increased the maximum mass they could lift from floor to knuckle height by 19% (68-81 kg, p < 0.001) and from floor to chest height by 16% (49-57 kg, p < 0.001). They improved by 17% their ability to lift 15 kg as many times as possible in 10 min(167-195 lifts, p < 0.001), while perception of effort (measured with the Borg Rating of Perceived Exertion) did not change. Total body mass did not change, but body fat mass was reduced by 9% (18.8-17.2 kg, p = 0.036) and fat-free mass increased by 6% (48.2-51.0 kg, p < 0.001). A short-term physical fitness program, conducted about 1 h per day, five days per week, can substantially improve women's MMH capability and provide favorable changes in body composition (increased fat-free mass and decreased body fat.  相似文献   
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We report analysis of both inorganic and amino acid forms of selenium by ion chromatography with inductively coupled plasma atomic emission spectroscopic detection. Three chromatographic systems are compared; effects of representative sample matrices on the separations are investigated. We are unable to resolve selenate and seleno-cystine using the Dionex AS4A column. Elution of seleno-cystine and seleno-cysteine is strongly suppressed in samples of bacterial cell extract matrix analyzed with the Dionex AS10 column; this interference is not observed with the Dionex AS11 column. Synthetic sea water sample matrix has little effect on analytical results. Quantitation parameters are reported.  相似文献   
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