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91.
Karin Ellen Veldkamp Kok P. M. Van Kessel Jan Verhoef Jos A. G. Van Strijp 《Inflammation》1997,21(5):541-551
Phagocytes play a major role in host defense against staphylococci as well as in the pathophysiology of Gram-positive septic shock. In Gram negative sepsis, the main mediator, LPS exerts its effects as easily suspendable mediator. In Gram positive sepsis the main mediator is still not found, therefore we studied the interaction of soluble staphylococcal products with phagocytes. Staphylococcus aureus supernates (SaS) were harvested from several laboratory and clinical strains that were grown to late-log phase. These supernates upregulated CD11b/CD18 expression on human neutrophils even in a 100-fold dilution. SaS also induced the release of TNF- and IL-1 by human monocytes. Control experiments excluded peptidoglycan, lipoteichoic acid, and toxin, leucocidin, TSST-1 and all enterotoxins as sole mediators. Endotoxin contamination was also excluded. SaS was heat-stable; incubation for 45 minutes at 100°C did not affect its activity. Compared to purified peptidoglycan and intact bacteria per bacterium, SaS had a higher potency in stimulating phagocytes. We hypothesize that there are more—yet unknown—soluble staphylococcal products which are very important in phagocyte stimulation. 相似文献
92.
Isolation and Purification of Treponema pallidum from Syphilitic Lesions in Rabbits 总被引:1,自引:5,他引:1 下载免费PDF全文
Treponema pallidum were extracted from testicular syphilomas of corticosteroid-treated rabbits and purified by differential centrifugation. The steroid therapy allowed a longer holding time for infected rabbits, which produced greater treponeme yields, averaging 1.58 × 1010 treponemes per rabbit. The treatment, which also diminished cellular infiltration and increased the extracellular mucoid material in lesions, produced much cleaner suspensions than preparations from nontreated animals. Most of the treponemes in the purified suspensions were still motile, and none carried demonstrable host immunoglobulin. The preparations were free of recognizable host tissue debris and they contained, on the average, 1.9 × 10−7 μg of protein per treponeme. 相似文献
93.
Autoimmunity in chronic bullous skin diseases. Immunofluorescent demonstration of three types of antibodies to skin in sera of patients with pemphigus, bullous pemphigoid and in other human sera 总被引:1,自引:0,他引:1 下载免费PDF全文
E. H. Beutner Ellen L. Rhodes E. J. Holborow 《Clinical and experimental immunology》1967,2(2):141-151
Antibodies to an intercellular substance of epidermis and other stratified squamous epithelia demonstrable by immunofluorescent staining have been reported to occur in the sera of patients with pemphigus vulgaris. Using sera of patients with bullous pemphigoid, antibodies to a component of the basement zone of skin had been found by the same technique. In the present study these observations have been confirmed and extended. In addition to the above mentioned immunofluorescent staining reactions, another type of antibody directed to a cytoplasmic or perinuclear component of epidermal cells was found in a variety of pathologic sera. This observation points to the need for differentiating other skin-reactive antibodies from those found only in pemphigus. Guinea-pig lip sections appeared to be satisfactory for these studies. Mixed immunofluorescence was found to yield staining reactions identical to those observed by the indirect staining method, and gave titres the same as or lower than those obtained by the indirect staining procedure. Using the indirect method with guinea-pig lip sections it was found that eight of ten sera of patients with pemphigus contained intercellular antibodies while 102 control sera failed to yield reactions of this type. The titres of antibodies appeared to be proportional to the severity of the disease process. Sera of two out of three patients suffering from bullous pemphigoid yielded immunofluorescence staining of the basement zone while 109 controls were negative for this antibody. 相似文献
94.
Balk Steven P.; Polischuk John E.; Probert Christopher; Stevens Christopher; Ebert Ellen; She Jian; Terhorst Cox; Blumberg Richard S. 《International immunology》1995,7(8):1237-1241
Human intestinal intraepithelial lymphocytes (DEL) are a uniquepopulation of predominantly CD8ß+ TCRß+lymphocytes and, to a lesser extent, TCR+ lymphocytes that proliferatepoorly to anti-CD3 mitogenic signals but display significantcytolytic activity. Studies in mouse model systems have shownthat the chain of the high-CD3 affinity receptor for IgE (FcRl)may substitute for the chain in the TCR-CD3 complex of iIEL.This has suggested that the functional properties of these cellsmay be associated with an altered composition of the TCR-CD3complex. We therefore analyzed the TCR-CD3 complex of normalhuman iIEL. One-and two-dimensional non-reducing/reducing SDS-PAGEanalysis of CD3, CD3, CD3, and FcRr chain immunopreclpitatesof cell surface radiolabeled proteins with subunit-specificantibodies revealed a TCR-CD3 complex without associated FcRrchains. Thus, normal human NEL contain a TCR-CD3 complex thatconsists predominantly of , homodimers in association with theß TCR and CD3, and , similar to the majority of peripherallymphocytes. This indicates that the distinct properties ofhuman DEL are not associated with substitutions of the FcRlchain in the TCR-CD3 complex. 相似文献
95.
Roger P. Farrar S.Mehdi Rezazadeh Jim L. Morris Jo Ellen Dildy Kim Gnau Steven W. Leslie 《Neuroscience letters》1989,100(1-3):319-325
Several lines of experimental evidence support an association between altered Ca2+ regulation and aging. It has been supposed that free cytosolic Ca2+ concentrations ([Ca2+]i) may decrease or increase in aged animals. In this study, both resting and KCl-stimulated [Ca2+]i were measured in purified cortical synaptosomes from young (3 mo.), middle-aged (12 mo.), and old (24 mo.) Fischer 344 rats. Two additional groups of rats were included, one middle-aged and one old which were trained on a treadmill for 6 months prior to experimentation. The [Ca2+]i was determined using the fluorescent Ca2+ chelator fura-2. Net KCl-dependent changes (ΔK) in [Ca2+]i were determined by the difference between stimulatory (100 μM Ca2+/60 mM KCl) and resting (100 μM Ca2+/5 mM KCl buffer) conditions among the 3 age groups. Significant increases in [Ca2+]i were observed in each age group upon depolarization with 60 mM KCl. However, there were no significant age-dependent differences in either resting [Ca2+]i or KCl-stimulated [Ca2+]i. 相似文献
96.
Michael W. O'Hara Claudia J. French Ellen M. Zekoski Danny J. Neunaber Gary W. Schroeder 《Cognitive therapy and research》1985,9(3):267-275
According to the reformulated learned helplessness model of depression, causal attributions are an important mediator of the effects on mood of positive and negative experiences. Adaptive attributions for negative events are assumed to be external, unstable, and specific. In the present study, subjects exposed to one of two attribution training procedures or a control condition made attributions for hypothetical events under neutral and adaptive instructional sets. Attributions were rated by subjects and coders blind to the purpose of the study. Results indicated that subjects' views of adaptive causal attributions were congruent with predictions from the learned helplessness model. The ratings of the objective coders indicated that subjects' attributions really did change in response to the adaptive instructions in the predicted direction. Implications of these results for the reformulated learned helplessness model and depression therapies that include an attribution retraining component are discussed.The authors would like to thank Dan Russell for his very helpful comments on earlier drafts of this paper. 相似文献
97.
Summary Previous studies have demonstrated that verapamil may overcome resistance to anthracyclines. In vitro and in vivo experiments were performed on wild-type and resistant Ehrlich ascites tumor cells.Verapamil in concentrations of 25–50 M enhances the accumulation of daunorubicin (DNR) in resistant cells to the same level as in wild-type cells. No significant effect of verapamil on influx or nuclear binding could be demonstrated, indicating that verapamil enhances DNR uptake by blocking active drug extrusion. Exposure of cells to a high concentration of Ca2+ did not influence the effect of verapamil on DNR accumulation, suggesting a different mode of verapamil action apart from the Ca2+-blocking effect. Attempts to circumvent acquired resistance to DNR in vivo with verapamil showed that the combination of the two drugs was more toxic than DNR given alone. The LD10 of DNR was determined as 3 mg/kg and the LD10 of the combination, as 2.5 mg/kg. The therapeutic effect of verapamil at a dose of 50 mg/kg and DNR of 2.5 mg/kg increased the life span of the mice by 50%. No difference was seen in the wild-type tumor in vivo.These data lead us to conclude that verapamil can reverse DNR resistance completely, but that verapamil at non-toxic dosage only reduces DNR resistance by 50% in vivo.The Danish Cancer Society, Copenhagen, Denmark, the Kathrine and Vigo Skovgaard Foundation, Holbæk, Denmark and the Anders Hasselbalch Foundation, Copenhagen, Denmark, kindly supported this work. 相似文献
98.
Guth Sarah McGinnis Ellen Copeland William Hudziak James 《Maternal and child health journal》2022,26(6):1203-1210
Maternal and Child Health Journal - This is a pilot study of the Vermont Family Based Approach, an innovative health promotion program designed to address behavioral health prevention in primary... 相似文献
99.
Abrar M. Babateen Oliver M. Shannon Gerard M. OBrien Edward Okello Anmar A. Khan Sofia Rubele Emma Wightman Ellen Smith Nicholas McMahon Dilara Olgacer Christina Koehl William Fostier Inês Mendes David Kennedy John C. Mathers Mario Siervo 《Nutrients》2021,13(3)
Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO3−) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m2) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO3− (HN: 2 × 70 mL BJ/day) (2) medium-NO3− (MN: 70 mL BJ/day), (3) low-NO3− (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO3−-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO3− intake, and by measuring NO3− and NO2− concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO3− dose and the increase in plasma and urinary NO3− concentration (R2 = 0.71, p < 0.001 and R2 = 0.46 p < 0.001, respectively), but relationships between NO3− dose and changes in salivary NO3− and NO2− were non-linear (R2 = 0.35, p = 0.002 and R2 = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults. 相似文献
100.
Kruti B. Shah Steven D. Chernausek Lori D. Garman Nathan P. Pezant Jasmine F. Plows Harmeet K. Kharoud Ellen W. Demerath David A. Fields 《Nutrients》2021,13(4)
Among all the body fluids, breast milk is one of the richest sources of microRNAs (miRNAs). MiRNAs packaged within the milk exosomes are bioavailable to breastfeeding infants. The role of miRNAs in determining infant growth and the impact of maternal overweight/obesity on human milk (HM) miRNAs is poorly understood. The objectives of this study were to examine the impact of maternal overweight/obesity on select miRNAs (miR-148a, miR-30b, miR-29a, miR-29b, miR-let-7a and miR-32) involved in adipogenesis and glucose metabolism and to examine the relationship of these miRNAs with measures of infant body composition in the first 6 months of life. Milk samples were collected from a cohort of 60 mothers (30 normal-weight [NW] and 30 overweight [OW]/obese [OB]) at 1-month and a subset of 48 of these at 3 months of lactation. Relative abundance of miRNA was determined using real-time PCR. The associations between the miRNAs of interest and infant weight and body composition at one, three, and six months were examined after adjusting for infant gestational age, birth weight, and sex. The abundance of miR-148a and miR-30b was lower by 30% and 42%, respectively, in the OW/OB group than in the NW group at 1 month. miR-148a was negatively associated with infant weight, fat mass, and fat free mass, while miR-30b was positively associated with infant weight, percent body fat, and fat mass at 1 month. Maternal obesity is negatively associated with the content of select miRNAs in human milk. An association of specific miRNAs with infant body composition was observed during the first month of life, suggesting a potential role in the infant’s adaptation to enteral nutrition. 相似文献