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1.
Tumor necrosis factor-alpha in whole blood cultures of preeclamptic patients and healthy pregnant and nonpregnant women. 总被引:4,自引:0,他引:4
Ilse Beckmann Shlomo Ben Efraim Monica Vervoort Wil Visser Henk C S Wallenburg 《Hypertension in pregnancy》2004,23(3):319-329
OBJECTIVES: Tumor necrosis factor-alpha (TNF-alpha) is recognized as a likely mediator of the excessive endothelial activation and injury that is a key pathogenetic mechanism of preeclampsia. We used whole blood cell cultures from 12 patients with severe preeclampsia and from 12 healthy pregnant and nonpregnant women to determine the release of TNF-alpha by unstimulated leukocytes as a measure of their state of activation, and their response to stimulation with lipopolysaccharide (LPS) as an indicator of their state of priming. METHODS: Blood was cultivated without and with LPS, and TNF-alpha release was measured after six and 24 hours of cultivation by enzyme-linked immunoassays. Differential leukocyte counts were performed, and TNF-alpha values calculated per 10(5) monocytes. RESULTS: In unstimulated whole blood cultures, TNF-alpha release after six hours of cultivation was similar in all three groups; but after 24 hours, TNF-alpha concentrations in culture supernatants from preeclamptic patients were significantly higher than were values obtained in blood from normotensive pregnant women. In LPS-stimulated blood cultures with a maximum of TNF-alpha release at six hours cultivation time, TNF-alpha concentrations were significantly lower in preeclamptic women than they were in both control groups. We showed in an additional experiment that a strong LPS challenge following preactivation with high doses of LPS resulted in reduced release of TNF-alpha compared with release of TNF-alpha following preactivation with low doses of LPS. CONCLUSIONS: The observed high capacity for spontaneous TNF-alpha release by leukocytes in preeclampsia indicates activation of TNF-alpha producing leukocytes by the disease process. Preactivation and exhaustion of leukocytes by leakage of TNF-alpha could lead to the reduced response to TNF-alpha inducer LPS as observed in blood cultures from preeclamptic patients. 相似文献
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Kees J.M. Lips Jaap Van Der Sluys Veer Albert Struyvenberg AD Alleman John R. Leo Paul Wittebol Werner H. Minder Cornelis J. Kooiker Rolf A. Geerdink Paul F.G.M. Van Waes Wil H.L. Hackeng 《The American journal of medicine》1981,70(5):1051-1060
Two kindreds with the multiple endocrine neoplasia type 2A syndrome were studied. Of one of these we examined 150 members, 20 of whom were treated with thyroidectomy for medullary carcinoma and nine with bilateral adrenalectomy for pheochromocytoma. Of the second kindred 59 members were examined, seven of whom were thyroidectomized and seven treated with bilateral adrenalectomy. Pheochromocytomas were invariably found on both sides, even in four cases in which the adrenals on one side appeared to be completely normal, not only at preoperative roentgenologic examination but also on inspection during the operation. The microscopic finding of micronodules and a cluster of abnormal medullary cells identical with those found in pheochromocytomas in one of the apparently normal adrenals represents a first stage in the development of diffuse medullary hyperplasia as well as nodular hyperplasia. This is in accordance with the fact that in the MEN type 2A syndrome pheochromocytomas are always multicentric and multiple in origin. On the basis of these findings we conclude that all patients with the MEN 2A syndrome who show symptoms and signs of active pheochromocytoma should be subjected to bilateral adrenalectomy, even when one or both of the adrenals appear to be normal at roentgenologic investigation. 相似文献
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Roebroeks W Sier MJ Nielsen TK De Loecker D Parés JM Arps CE Mücher HJ 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(6):1889-1894
The use of manganese and iron oxides by late Neandertals is well documented in Europe, especially for the period 60-40 kya. Such finds often have been interpreted as pigments even though their exact function is largely unknown. Here we report significantly older iron oxide finds that constitute the earliest documented use of red ochre by Neandertals. These finds were small concentrates of red material retrieved during excavations at Maastricht-Belvédère, The Netherlands. The excavations exposed a series of well-preserved flint artifact (and occasionally bone) scatters, formed in a river valley setting during a late Middle Pleistocene full interglacial period. Samples of the reddish material were submitted to various forms of analyses to study their physical properties. All analyses identified the red material as hematite. This is a nonlocal material that was imported to the site, possibly over dozens of kilometers. Identification of the Maastricht-Belvédère finds as hematite pushes the use of red ochre by (early) Neandertals back in time significantly, to minimally 200-250 kya (i.e., to the same time range as the early ochre use in the African record). 相似文献
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Effect of dosing and dosing frequency on the efficacy of ceftizoxime and the emergence of ceftizoxime resistance during the early development of murine abscesses caused by Bacteroides fragilis and Enterobacter cloacae mixed infection 下载免费PDF全文
Stearne LE Goessens WH Mouton JW Gyssens IC 《Antimicrobial agents and chemotherapy》2007,51(10):3605-3611
The efficacy of beta-lactams is thought to be dependent on the time that the unbound concentrations exceed the MIC (fT>MIC). However, the pharmacokinetic/pharmacodynamic index (PDI) that correlates best to the selection of resistance is not yet clear. The selection of ceftizoxime (CZX)-resistant Enterobacter cloacae mutant strains during the development of murine mixed-infection abscesses was studied to determine the PDI that is important for the emergence of resistance and the PDI value needed for the prevention of resistance. Studies were carried out 24 h after inoculation with Bacteroides fragilis ATCC 23745 and E. cloacae 22491. Six to 1,536 mg of CZX/kg of body weight/day given every 2 h (q2h), q4h, q6h, or q8h was started 30 min before inoculation and continued for 24 h. Resistant mutants were isolated to determine mutant frequencies (MF). The fT>MIC varied from 9 to 98% for E. cloacae, the peak concentration (unbound fraction) was 0.6 to 578 mg/liter, and the area under the concentration-time curve (unbound fraction) (fAUC) was 1.9 to 553 mg.h/liter. The fAUC-to-MIC ratio best explained the in vivo efficacy. CZX-resistant B. fragilis and E. cloacae mutants were isolated from untreated controls at an MF of 10(-5) to 10(-7). The MF of resistant B. fragilis did not increase during therapy. The selection of resistant E. cloacae strains at an MF of 10(-1) to 10(-2) was related to the fT>MIC and the ratio of fAUC to MIC following an inverse U shape. However, the ratio of fAUC to MIC was the stronger driver of resistance. The highest MFs were 0.7 to 0.9 at an fAUC-to-MIC ratio of approximately 250. We conclude that the ratio of fAUC to MIC is the PDI that correlated best to the in vivo efficacy of CZX and probably also to the emergence of resistant E. cloacae mutants. An fAUC-to-MIC ratio of 1,000 was needed to prevent the emergence of this resistance. 相似文献
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Robert-Jan Hassing Wil H.F. Goessens Wilfrid van Pelt Dik J. Mevius Bruno H. Stricker Nicky Molhoek Annelies Verbon Perry J.J. van Genderen 《Emerging infectious diseases》2014,20(4):705-708
Antimicrobial susceptibility was analyzed for 354 typhoidal Salmonella isolates collected during 1999–2012 in the Netherlands. In 16.1% of all isolates and in 23.8% of all isolates that showed increased MICs for ciprofloxacin, the MIC for azithromycin was increased. This resistance may complicate empirical treatment of enteric fever. 相似文献
10.
de Grauw WJ van Gerwen WH van de Lisdonk EH van den Hoogen HJ van den Bosch WJ van Weel C 《The Journal of family practice》2002,51(5):459-464
OBJECTIVE: To assess the outcome of diabetes care in a practice-based research network after the introduction of an audit-enhanced monitoring system (AEMS). STUDY DESIGN: An AEMS was introduced into family practices participating in the academic research network of Nijmegen University, Nijmegen, the Netherlands. One and 7 years later, a cross-sectional analysis was performed on the outcome of care in all type 2 diabetes patients under treatment by their family physicians. POPULATION: Approximately 42,000 patients in 1993 and approximately 46,000 patients in 1999 at 10 family practices participating in the university's academic research network. OUTCOMES MEASURED: Targets of care were HbA1c < 8.5% and blood pressure < 150/85 mm Hg. Targets for lipids depended on age, cardiovascular morbidity, and smoking status. RESULTS: In 1993, 540 type 2 diabetes patients were included; in 1999, 851 such patients were included, representing a prevalence of 1.3% and 2.0%, respectively. Glycemic control improved statistically significantly by the percentage of patients with HbA1c < 8.5% (87% vs 59%, P =.0001) and the mean HbA1c (7.1% vs 8.2%, P =.0001) from the first to the second cohort. Mean blood pressure and the percentage of patients above the target blood pressure did not change. The mean cholesterol (207 mg/dL vs 238 mg/dL [5.4 mmol/L vs 6.2 mmol/L], P =.0001) and the percentage of patients who met their target lipid levels (72% vs 52%, P =.001) also improved between 1993 and 1999. In addition, an increased percentage of patients attended an annual review in the past year (73% vs 84%). CONCLUSIONS: Outcomes of diabetes care in a family practice research setting using an AEMS were comparable with those reported under randomized controlled trial conditions. 相似文献