Benign giant cell tumor of bone with osteosarcomatous transformation (”dedifferentiated” primary malignant GCT): report of two cases

 It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or ”dedifferentiating” into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional, benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there is a mesenchymal cell line in GCT that may spontaneously tansform to sarcoma.     

Angiographic demonstration of atherosclerotic stenosis, arterial spasm, and thrombus formation in an infarct-related coronary artery

Clinical, angiographic, and pathologic data support the contention that atherosclerosis, platelet aggregation, and coronary vasomotility work in unison to cause coronary thrombosis, which in turn leads to myocardial infarction. A patient is described in whom, 2 months after an acute myocardial infarction, inducible coronary artery spasm and a nonocclusive thrombus were angiographically demonstrated at the site of a minimal atherosclerotic narrowing in the infarction-related vessel. This report, to the best of our knowledge, is the first time that these three pathophysiologic mechanisms have been shown, in vivo, to be occurring concomitantly in an infarct-related vessel. Documentation of the unified occurrence of these phenomena support the current concept of the pathophysiology of myocardial infarction.     

Generation of volatile hydrocarbons from amino acids and proteins by an iron/ascorbate/GSH system

Incubation of free, but not of peptide-bound methionine in an iron/ascorbate system resulted in ethylene generation, which was inhibited by glutathione. Leucine and isoleucine, however, when incubated in an iron/ascorbate/GSH system, released small amounts of propane and ethane, respectively. Peptide-bound leucine additionally yielded butane, as did bovine serum albumin or casein. Hydrocarbon generation from amino acids was inhibited by hydroxyl radical scavengers, but catalase and superoxide dismutase were more efficient. Additionally, ethane and propane generation in this system was optimal at pH 6.2 suggesting the involvement of protonated superoxide besides OH-radicals which attack the side chains of Leu and Ile and very probably produce carbon-centered radicals, which should abstract a hydrogen atom from the thiol group of GSH resulting in the formation of saturated hydrocarbons.     

原发性帕金森病患者自主神经功能障碍的决定因素

目的:本文旨在确定影响原发性帕金森病(IPD)患者自主神经功能障碍严重程度的人口统计学或疾病相关因素。方法:532例年龄为55～75岁的IPD患者纳入本研究。采用自主神经功能障碍量表(A D S)对自主神经功能障碍的严重程度进行评估。另外,记录影响自主神经功能障碍严重程度的人口统     

Frequency of in vitro resistance of Pseudomonas aeruginosa to cefepime, ceftazidime, and cefotaxime.

The selection frequencies of cefepime (BMY 28142), ceftazidime, and cefotaxime resistance among Pseudomonas aeruginosa strains were determined. Cefepime-resistant mutants were not selected by cefepime (frequency, less than 10(-11)). Ceftazidime- and cefotaxime-resistant mutants were isolated at frequencies of 10(-5) to 10(-10) and were often cross-resistant. However, cefepime resistance among ceftazidime- and cefotaxime-resistant mutants was rare. Selected mutants resistant to cefepime constitutively produced 40- to 450-fold more beta-lactamase than did the parent strain.     

Anxiety and hippocampus volume in the rat.

In depressed patients as well as healthy controls, a positive relationship between hippocampal volume and trait anxiety has been reported. This study sought to explore the possible inter-relation between hippocampal volume and trait anxiety further. Magnetic resonance imaging at 7 T was used to measure hippocampal volumes in a rat model of extremes in trait anxiety (experiment 1) and in a Wistar population with normal anxiety-related behavior (experiment 2). In addition to anxiety-related behavior, potentially confounding factors (depression-like, exploratory, and locomotor behavior) were assessed. Experiment 1 globally supported the hypothesis of a positive relationship between hippocampus volume and trait anxiety but did not allow for ruling out possible confounds arising from cosegregation of other behavioral traits. Experiment 2 yielded strong evidence for a negative relationship which was specific for trait anxiety. Thus, the relationship between hippocampal volume and anxiety may be more complex than expected. Interestingly, anxiety-related behavior in experiment 2 had a stronger influence on hippocampal volume than depression-like behavior. In the light of hippocampal volume loss in anxiety disorder and frequent comorbidity of anxiety and depression, this finding suggests that further research into the relationship between anxiety and hippocampal volume may be critical for understanding hippocampal contributions to normal and pathological behavior.     

The use of telescoping guide catheters for coronary sinus cannulation and sub-selecting tributaries in left ventricular lead placement

Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding the need for catheter change. Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant. Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter. Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for sub-selecting the CS tributaries.     

Neonatal Exposure to a Combination of N-Methyl-d-aspartate and γ-Aminobutyric Acid Type A Receptor Anesthetic Agents Potentiates Apoptotic Neurodegeneration and Persistent Behavioral Deficits

Background: During the brain growth spurt, the brain develops and modifies rapidly. In rodents this period is neonatal, spanning the first weeks of life, whereas in humans it begins during the third trimester and continues 2 yr. This study examined whether different anesthetic agents, alone and in combination, administered to neonate mice, can trigger apoptosis and whether behavioral deficits occur later in adulthood.

Methods: Ten-day-old mice were injected subcutaneously with ketamine (25 mg/kg), thiopental (5 mg/kg or 25 mg/kg), propofol (10 mg/kg or 60 mg/kg), a combination of ketamine (25 mg/kg) and thiopental (5 mg/kg), a combination of ketamine (25 mg/kg) and propofol (10 mg/kg), or control (saline). Fluoro-Jade staining revealed neurodegeneration 24 h after treatment. The behavioral tests-spontaneous behavior, radial arm maze, and elevated plus maze (before and after anxiolytic)-were conducted on mice aged 55-70 days.

Results: Coadministration of ketamine plus propofol or ketamine plus thiopental or a high dose of propofol alone significantly triggered apoptosis. Mice exposed to a combination of anesthetic agents or ketamine alone displayed disrupted spontaneous activity and learning. The anxiolytic action of diazepam was less effective when given to adult mice that were neonatally exposed to propofol.