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991.
Effect of netilmicin on the phospholipid composition of subcellular fractions of rat renal cortex 总被引:2,自引:0,他引:2
C Josepovitz T Farruggella R Levine B Lane G J Kaloyanides 《The Journal of pharmacology and experimental therapeutics》1985,235(3):810-819
The purpose of this study was to determine the subcellular site(s) of the renal cortical phospholipidosis induced by aminoglycosides. For this purpose we injected male Sprague-Dawley rats s.c. with netilmicin, containing tracer quantities of [3H]netilmicin, at 100 mg/kg/day for 2 days; control rats were injected with saline. Twenty-four hours after the second injection of drug the rats were sacrificed and the renal cortex was fractionated by differential ultracentrifugation and Percoll gradient density techniques to obtain purified lysosomes, mitochondria, microsomes, brush border membranes and basolateral membranes. The total phospholipid content of the renal cortex was 300 +/- 5 nmol/mg of protein in control rats and 340 +/- 5 nmol/mg of protein in netilmicin-injected rats. The total phospholipid content of the lysosomal fraction of netilmicin rats, which was enriched in myeloid bodies and [3H]netilmicin, was 91% greater than that of control rats and reflected significant increases of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylinositol. This pattern is identical to that reported previously for the rat renal cortical phospholipidosis induced by aminoglycosides. The total phospholipid contents of the mitochondrial, microsomal, brush border membrane and basolateral membrane fractions of netilmicin-injected rats were higher by approximately 10% than the respective fractions of control rats and each fraction exhibited a significant increase of one or more of the four phospholipids elevated in the renal cortical homogenate and in the lysosomal fraction. The data indicate that the myeloid body is the primary source of the lysosomal phospholipidosis induced by netilmicin which provides support for the hypothesis that the lysosomal phospholipidosis is secondary to aminoglycoside-induced inhibition of phospholipid degradation. In addition the findings of increased phospholipid content and altered phospholipid composition of the other subcellular fractions raise the possibility that aminoglycoside antibiotics cause a more generalized disturbance of phospholipid metabolism characterized by altered synthesis as well as degradation in renal proximal tubular cells. 相似文献
992.
In-vitro evaluation of cefpirome (HR 810), teicoplanin and four other antimicrobials against enterococci 总被引:2,自引:0,他引:2
In-vitro activities of cefpirome (HR 810), a fourth generation cephalosporin, and teicoplanin were compared with those of ampicillin, piperacillin, and vancomycin against 56 clinical isolates of enterococci. Cefpirome had good activity with the MIC90 and MBC90 being 4 and 16 mg/l. Ampicillin and piperacillin had MBC90 of 4 and 16 mg/l. Teicoplanin was extremely active with the MIC90 being 1.6 mg/l while vancomycin had poor cidal activity with the MBC90 being 16 mg/l. A decrease in activity of cefpirome was noted when the inoculum size was increased from 10(3) to 10(7) organisms per ml. Synergy was demonstrated against most Streptococcus faecium isolates with a combination of cefpirome and gentamicin or piperacillin. Against Str. faecalis, with a similar combination, synergy was seen in less than 50% isolates. No antagonism was noted with any of the antibiotic combinations. 相似文献
993.
E. Levine N. Beroul A. Cortey A. Damais Cepitelli H. Gouezec S. Pujol B. Wibaut B. Marti 《Transfusion Clinique et Biologique》2018,25(4):249-256
Background
Blood transfusion is common in neonatology, especially in preterm or low birth weight infants. Recommendations were proposed by the French National Authority of Health (HAS) in 2014 and 2015 for red blood cells and platelet transfusion respectively, but an heterogeneity of practical attitudes persist. The objective of this survey is to evaluate transfusion practices in neonatal intensive care units.Methods
Investigation of practice of neonatal transfusion was organized among 68 neonatal intensive care unit (level 3) between September 2016 and May 2017, by mailing survey focused on systematic training of nurses, patient identification, immunohematology, information and technical aspects of blood components administration.Results
Twenty-three neonatal intensive care units among the 68s answered the questionnaire. One thousand five hundred sixty seven neonates were transfused and 3382 blood products were administered. The results highlight a consensual attitude concerning the procedures of patient identification, immunohematology tests and blood products administration. However, heterogeneity remains concerning information of the parents or the person with parental authority, immediate and delayed follow-up and devices used for the transfusion. However HAS guidelines (2014 and 2015) appear to be well applied by clinicians for blood products, specifications and calcul of transfused volume based on gestational age and weight. 相似文献994.
Sinus headache: a neurology, otolaryngology, allergy, and primary care consensus on diagnosis and treatment 总被引:4,自引:0,他引:4
Cady RK Dodick DW Levine HL Schreiber CP Eross EJ Setzen M Blumenthal HJ Lumry WR Berman GD Durham PL 《Mayo Clinic proceedings. Mayo Clinic》2005,80(7):908-916
Sinus headache is a widely accepted clinical diagnosis, although many medical specialists consider it an uncommon cause of recurrent headaches. The inappropriate diagnosis of sinus headache can lead to unnecessary diagnostic studies, surgical interventions, and medical treatments. Both the International Headache Society and the American Academy of Otolaryngology-Head and Neck Surgery have attempted to define conditions that lead to headaches of rhinogenic origin but have done so from different perspectives and in isolation of each other. An interdisciplinary ad hoc committee convened to discuss the role of sinus disease as a cause of headache and to review recent epidemiological studies that suggest sinus headache (headache of rhinogenic origin) and migraine are frequently confused with one another. This committee reviewed available scientific evidence from multiple disciplines and concluded that considerable research and clinical study are required to further understand and delineate the role of nasal pathology and autonomic activation in migraine and headaches of rhinogenic origin. However, this group agreed that greater diagnostic and therapeutic attention needs to be given to patients with sinus headaches. 相似文献
995.
S P Levine R L Kett P S Cederna S V Brooks 《Archives of physical medicine and rehabilitation》1990,71(3):210-215
This study measured changes in tissue shape and deformation at the seating interface produced by electric muscle stimulation (EMS) of the gluteus maximus. The purpose of the study was to investigate the application of EMS for pressure sore prevention. Limitations of pressure measurements for analysis of load distribution are discussed and a rationale developed for using tissue shape and deformation to further characterize the seating interface. Ultrasonic imaging of the seating interface is described under three conditions: buttocks suspended, external load applied with no EMS, and external load applied with bilateral EMS of the buttocks. Results show that low level stimulation of the gluteus maximus produces substantial changes in the shape of the loaded buttocks and an external contour more nearly shaped like the suspended buttocks. It is concluded that EMS produces buttock tissue undulation and shape reconfiguration which may assist in preventing pressure sores over the seating surface. 相似文献
996.
Marc S. Levine M.D. Donna Turner Olle Ekberg Stephen E. Rubesin David A. Katzka 《Abdominal imaging》1991,16(1):99-103
The authors performed a retrospective study of 50 patients with endoscopically diagnosed duodenitis who had undergone double-contrast upper gastrointestinal (GI) examinations. Duodenitis was diagnosed on the original radiographic reports in six of 37 patients (16%) with mild-to-moderate duodenitis, five of 13 patients (38%) with severe duodenitis, and 11 of 50 patients (22%) with all grades of duodenitis on endoscopy. Subsequent analysis of the films revealed one or more radiologic signs of duodenitis (including folds more than 4 mm in thickness, mucosal nodularity, bulbar deformity, and erosions) in 18 of 37 patients (49%) with mild-to-moderate duodenitis, eight of 13 patients (62%) with severe duodenitis, and 26 of 50 patients (52%) with all grades of duodenitis on endoscopy. In a separate part of the study, the authors identified another 20 patients with radiographically diagnosed duodenitis who had undergone endoscopic examinations. Nine of those 20 patients (45%) had duodenitis on endoscopy. Subsequent analysis of the films revealed one or more signs of duodenitis in 17 patients from this group. Nine of the latter patients (53%) had duodenitis on endoscopy. Using established radiologic criteria for duodenitis, our rate of false-positive and false-negative radiologic diagnoses still was about 50%. Thus, the double-contrast upper GI examination is a relatively unreliable technique for diagnosing duodenitis. 相似文献
997.
Levine MS 《Abdominal imaging》2005,30(2):133-141
Barrett esophagus is a well-recognized entity in which there is progressive columnar metaplasia of the lower esophagus due to longstanding gastroesophageal reflux and reflux esophagitis [1]. This condition is important because it is associated with an increased risk of developing esophageal adenocarcinoma by a well-established sequence from dysplasia to carcinoma [2]. During the past decade, however, an explosion of new data has dramatically affected our understanding of Barrett esophagus. Not only have revised histopathologic criteria been developed for this condition, but it is currently believed that patients with Barrett esophagus should be classified as having short-segment or long-segment disease based on the extent of columnar metaplasia in the distal esophagus. This distinction has important implications for the risk of developing esophageal adenocarcinoma and subsequent need for endoscopic surveillance. The purpose of this article is to present these new concepts about Barrett esophagus and provide radiologists with a more current framework for diagnosing this condition. 相似文献
998.
Akihisa Kataoka Xin Zeng J. Luis Guerrero Adam Kozak Gavin Braithwaite Robert A. Levine Gus J. Vlahakes Judy Hung 《The Journal of thoracic and cardiovascular surgery》2018,155(4):1485-1493
Objectives
Ischemic mitral regurgitation (IMR) results from ischemic left ventricular (LV) distortion and remodeling, which displaces the papillary muscles and tethers the mitral valve leaflets apically. The aim of this experimental study was to examine efficacy of an adjustable novel polymer filled mesh (poly-mesh) device to reverse LV remodeling and reduce IMR.Methods
Acute (N = 8) and chronic (8 weeks; N = 5) sheep models of IMR were studied. IMR was produced by ligation of circumflex branches to create myocardial infarction. An adjustable poly-mesh device was attached to infarcted myocardium in acute and chronic IMR models and compared with untreated sham sheep. Two- and 3-dimensional echocardiography and hemodynamic measurements were performed at baseline, post IMR, and post poly-mesh (humanely killed).Results
In acute models, moderate IMR developed in all sheep and decreased to trace/mild (vena contracta: 0.50 ± 0.09 cm to 0.26 ± 0.12 cm; P < .01) after poly-mesh. In chronic models, IMR decreased in all sheep after poly-mesh, and this reduction persisted over 8 weeks (vena contracta: 0.42 ± 0.09 cm to 0.08 ± 0.12 cm; P < .01) with significant increase in the slope of end-systolic pressure–volume relationship (1.1 ± 0.5 mm Hg/mL to 2.9 ± 0.7 mm Hg/mL; P < .05). There was a significant reduction in LV volumes from chronic IMR to euthanasia stage with poly-mesh compared with sham group (%end-diastolic volume change ?20 ± 11 vs 15% ± 16%, P < .01; %end-systolic volume change ?14% ± 19% vs 22% ± 22%, P < .05; poly-mesh vs sham group) consistent with reverse remodeling.Conclusions
An adjustable polymer filled mesh device reduces IMR and prevents continued LV remodeling during chronic follow-up. 相似文献999.
W G Levine J Bognacki 《The Journal of pharmacology and experimental therapeutics》1976,196(2):486-492
When rats treated for 2 days with nafenopin are injected i.v. with 3H-3,4-benzpyrene (BP), blood disappearance rates and liver levels of the carcinogen and the rate of biliary excretion of its metabolites are, in the main, similar to those of nontreated rats. This is in accord with the observation that nafenopin does not inhibit the metabolism of BP, which is the rate-limiting step in its biliary excretion. On the other hand, when 3H-BP metabolites are injected, nafenopin pretreatment slightly retards their rate of plasma disappearance and markedly inhibits their biliary excretion, as it does other organic anions. When rats are pretreated with 3-methylcholanthrene, the rate of metabolism of 3H-BP and consequently the biliary excretion of its metabolites is greatly stimulated. In this instance, metabolism may no longer be rate-limiting in the overall biliary excretion process and inhibition by nafenopin of liver-to-bile transport of metabolites can be observed. Since nafenopin pretreatment stimulates the synthesis of new liver tissue, it is presently a matter of conjecture as to whether or not the newly formed hepatocytes have the capacity to take up and excrete BP and its metabolites or whether nafenopin inhibits transport in all liver tissue. 相似文献
1000.