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1.
S Y Wang H Castro-Malaspina M A Moore 《Journal of immunology (Baltimore, Md. : 1950)》1985,135(2):1186-1193
We describe a liquid culture system allowing the long-term maintenance and differentiation of human marrow monocytes into well-developed, lipid-containing macrophages, and we show that these cells produce a regulating activity that enhances the colony formation induced by granulocyte-macrophage colony-stimulating factors (GM-CSF). Adherent, low density (less than 1.074 g/cm3) human marrow cells were used as a source of monocytic cells. Of 12 different culture conditions tested, alpha-medium supplemented with 20% horse serum and incubation at 37 degrees C provided the best conditions for macrophage development, adipogenesis, and long-term culture. Neither insulin (1 to 10 micrograms/ml) nor hydrocortisone (10(-6) M) improved the lipid accumulation in cultures containing horse serum. Trypsin was employed to remove fibroblasts without detaching monocytic cells from the marrow-derived adherent cell layers. Marked structural and functional changes characterized the transformation of monocytes into lipid-containing macrophages. Cell enlargement up to seven or eight times by 21 to 28 days of culture was associated with an increase in small and medium-sized lipid granules, as well as in acid phosphatase and nonspecific esterase activities. Ultrastructurally, there was an increase in the number of mitochondria, Golgi apparatus, lysosomes, rough endoplasmic reticulum, and lipid inclusions, which remained of small size and did not coalesce to form larger inclusions. The absolute quantity of Fc receptors, Ia antigens, and antigens recognized by monoclonal antibodies 61D3 and 63D3 also increased as a function of cell size. As marrow monocyte-macrophage differentiation proceeded, a rapid decline in GM-CSF production was accompanied by an increase in an activity that by itself had no capacity to stimulate colony formation in CFU-GM cultures devoid of GM-CSF, but did enhance the colony formation induced by optimal concentrations of GM-CSF. Neither the enhancing activity nor its production was related to the horse serum present in the culture supernatants. The morphology of colonies enhanced by this activity was different from the morphologic spectrum in non-enhanced cultures. This granulomonopoietic enhancing activity (GM-EA) represents another positive feedback regulator of hematopoiesis derived from cells of the monocyte-macrophage system. 相似文献
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Isolation of avian paramyxovirus 1 from a patient with a lethal case of pneumonia 总被引:4,自引:0,他引:4
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Goebel SJ Taylor J Barr BC Kiehn TE Castro-Malaspina HR Hedvat CV Rush-Wilson KA Kelly CD Davis SW Samsonoff WA Hurst KR Behr MJ Masters PS 《Journal of virology》2007,81(22):12709-12714
An unknown virus was isolated from a lung biopsy sample and multiple other samples from a patient who developed a lethal case of pneumonia following a peripheral blood stem cell transplant. A random PCR-based molecular screening method was used to identify the infectious agent as avian paramyxovirus 1 (APMV-1; a group encompassing Newcastle disease virus), which is a highly contagious poultry pathogen that has only rarely been found in human infections. Immunohistochemical analysis confirmed the presence of APMV-1 antigen in sloughed alveolar cells in lung tissue from autopsy. Sequence from the human isolate showed that it was most closely related to virulent pigeon strains of APMV-1. This is the most completely documented case of a systemic human infection caused by APMV-1 and is the first report of an association between this virus and a fatal disease in a human. 相似文献
3.
Little is known about the effect of exercise training on the expression of adiponectin receptor genes in peripheral blood mononuclear cells (PBMCs). In this study, we investigated the effects of aerobic training on the expression of AdipoR1 and AidpoR2 mRNAs in PBMCs, whole body insulin sensitivity, and circulating adiponectins in men. Thirty young men were randomly assigned to either a control (n=15) or an exercise (n=15) group. Subjects assigned to the exercise group underwent a 12-week jogging and/or running programme on a motor-driven treadmill at an intensity of 60%-75% of the age-based maximum heart rate with duration of 40 minutes per session and a frequency of 5 days per week. Two-way mixed ANOVA with repeated measures was used to test any significant time-by-group interaction effects for the measured variables at p=0.05. We found significant time-by-group interaction effects for waist circumference (p=0.001), VO2max (p<0.001), fasting insulin (p=0.016), homeostasis model assessment for insulin resistance (HOMA-IR) (p=0.010), area under the curve (AUC) for insulin response during the 75-g oral glucose tolerance test (p=0.002), high-molecular weight (HMW) adiponectin (p=0.016), and the PBMC mRNA levels of AdipoR1 (p<0.001) and AdipoR2 (p=0.001). The exercise group had significantly increased mRNA levels of AdipoR1 and AdipoR2 in PBMCs, along with increased whole body insulin sensitivity and HMW adiponectin, decreased waist circumference, and increased VO2max compared with the control group. In summary, the current findings suggest that exercise training modulates the expression of AdipoR1 and AdipoR2 mRNAs in PBMCs, implying that manipulation of the expression of these genes could be a potential surrogate for lifestyle intervention-mediated improvements of whole body insulin sensitivity and glucose homeostasis. 相似文献
4.
Genetic and environmental heterogeneity of residual variance of weight traits in Nellore beef cattle
Background
Many studies have provided evidence of the existence of genetic heterogeneity of environmental variance, suggesting that it could be exploited to improve robustness and uniformity of livestock by selection. However, little is known about the perspectives of such a selection strategy in beef cattle.Methods
A two-step approach was applied to study the genetic heterogeneity of residual variance of weight gain from birth to weaning and long-yearling weight in a Nellore beef cattle population. First, an animal model was fitted to the data and second, the influence of additive and environmental effects on the residual variance of these traits was investigated with different models, in which the log squared estimated residuals for each phenotypic record were analyzed using the restricted maximum likelihood method. Monte Carlo simulation was performed to assess the reliability of variance component estimates from the second step and the accuracy of estimated breeding values for residual variation.Results
The results suggest that both genetic and environmental factors have an effect on the residual variance of weight gain from birth to weaning and long-yearling in Nellore beef cattle and that uniformity of these traits could be improved by selecting for lower residual variance, when considering a large amount of information to predict genetic merit for this criterion. Simulations suggested that using the two-step approach would lead to biased estimates of variance components, such that more adequate methods are needed to study the genetic heterogeneity of residual variance in beef cattle. 相似文献5.
6.
Lipid composition of whole roots of wheat (Triticum vulgare Vill. cv. Svenno Spring Wheat) and oat (Avena sativa L. cv. Brighton) and of cell wall fractions, mitochondrial fractions and microsomal fractions of these roots were studied. Lipid composition depended upon the level of mineral nutrition. In wheat total phospholipids, phosphatidyl choline and sulfolipid content was highest in the roots grown at the higher salt concentration, while the reverse was true for oat roots. In both species glycolipid and sterol content was lower in the high salt roots, at the same time as higher proportions of them were built into the microsomal fraction. Phosphatidyl choline content of the wheat root membrane fractions increased with the salt level, while the opposite occurred in the oat roots. The phosphatidyl choline content may be correlated with the (Ca2+, Mg2+)-stimulated ATPase activity. 相似文献
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Activation by Ca2+, Mg2+, Zn2+, or Mn2+ of adenosine triphosphatases in a microsomal fraction from wheat roots depends upon the growth temperature when the plants are grown under low salt conditions, but not when the plants get a full-strength culture medium. At low ionic strength, cultivation at 25°C gives only half as high activation as cultivation at 18°C or at high ionic strength at both temperatures. Corresponding data for activation of ATPases from oats also show that low ionic strength during growth gives the highest temperature dependence. Low temperature together with low salt conditions during growth gives the highest ATPase activity after stimulation with divalent cations. High growth temperature and full-strength medium decrease the ATPase activity. Activation energies (Ea) were calculated for the two temperature intervals 35–20°C and 20–5°C. The dominating ATPase stimulation (Ca2+ in wheat, Mg2+ in oats) is characterized by high specific activity combined with a low Ea value. The differences in ATPase activity between oats and wheat can be correlated with different cultivation requirements known from agriculture. 相似文献
9.
C. STÖHR 《Plant, cell & environment》1999,22(2):169-177
cNR, cytosolic nitrate reductasePM-NR, plasma membrane-bound nitrate reductaseActivities of plasma membrane-bound nitrate reductase (PM-NR) and cytosolic nitrate reductase (cNR) in tobacco (Nicotiana tabacum L. cv. Samsun) are regulated differently, depending upon the nitrate supply to the culture medium (in sand culture). The cNR activity of roots was higher at low nitrate concentrations with the maximum at 5 mM nitrate supply and declined to low values beyond 5 mM . In contrast, the PM-NR activity of roots increased with higher nitrate concentrations with the maximum at 25 mM nitrate and clearly decreased only at 40 mM . This high PM-NR activity correlated with a low growth rate and might be one of the responses to excess nitrate. Internal nitrate and total nitrogen content of the tissues, however, showed a relative minimum in shoots and in roots of between 15 and 25 mM external nitrate. With declining PM-NR activities beyond 25 mM external nitrate, the nitrate content in the tissue increased indicating an inverse relationship between tissue nitrate content and root PM-NR activity. In leaves both NR activities (cNR and PM-NR) correlated with the internal nitrate content, but with a different response at low nitrate. 相似文献
10.
Haroldo HR Neves Roberto Carvalheiro Ana M Pérez O’Brien Yuri T Utsunomiya Adriana S do Carmo Flávio S Schenkel Johann S?lkner John C McEwan Curtis P Van Tassell John B Cole Marcos VGB da Silva Sandra A Queiroz Tad S Sonstegard José Fernando Garcia 《遗传、选种与进化》2014,46(1):17