Acute resynchronization with inhaled iloprost in a pregnant woman with idiopathic pulmonary artery hypertension.

We describe the case of a pregnant woman with idiopathic pulmonary arterial hypertension, a responder in right heart catheterization, followed since the first trimester in outpatient consultations, admitted to hospital at 23 weeks gestation. She was treated with inhaled iloprost until delivery (at 34 weeks gestation) and continuous infusion of iloprost throughout the perioperative period and following days. This line of therapy has proved efficacious in previous cases. The authors present echocardiographic images that document acute changes in ventricular synchrony during inhalation of iloprost.     

系统性红斑狼疮女性患者血清CA125,CA199化学发光法测定的临床应用

目的 :探讨系统性红斑狼疮 (SLE)女性患者血清肿瘤标志物CA12 5 ,CA199含量变化及临床意义。方法 :用化学发光法测定 30例正常女性和 38例SLE女性患者血清中CA12 5 ,CA199含量。结果 :正常组CA12 5含量为 11.14± 6 .4 8U/ml,CA199含量为 3.75± 2 .89U/ml;SLE组CA12 5 ,CA199分别为 2 2 .5 6± 2 0 .4 6U/ml,9.5 7± 9.34U/ml。SLE患者CA12 5 ,CA199阳性率分别为 2 1.1% ,7.89%。结论 :SLE患者血清CAl2 5 ,CA199含量较正常组增高 (P <0 .0 5 )。CA12 5 ,CA199在SLE女性患者中可出现阳性 ,对临床诊断SLE有一定价值。     

Antioxidant and glutathione-related enzymatic activities in rat sciatic nerve

The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage.     

Melatonin reduces nitric oxide synthase activity in rat hypothalamus

Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity.     

Immunology

A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.     

Focus on anti-atherosclerotic therapy

Calcium antagonists (CA) exert an anti-atherosclerotic effect in cholesterol-fed rabbits through reduction of cholesterol accumulation in the arterial wall. Further studies in our Institute indicate that verapamil-like compounds and diltiazem stimulate receptor-mediated LDL uptake by human fibroblasts in culture, while nifedipine-like compounds and flunarizine are inactive. Verapamil and diltiazem stimulated LDL-receptor activity also in cells from a heterozygous FH patient, while they were inactive in a receptor defective homozygous FH patient. A basic group needs to be present on the CA molecule to modulate the LDL receptor expression. Preliminary data in our laboratory suggest that some CA can achieve concentrations in the aortic wall likely to exert effects on LDL receptors. This stimulatory activity may improve lipid metabolism in the arterial wall.Corresponding author     

Serotonin 5- HT (2C) receptor knockout mice: autoradiographic analysis of multiple serotonin receptors.

Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.     

Improved intracranial lesion characterization by tissue segmentation based on a 3D feature map

Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T₂-weighted fast spin-echo (FSE), and T₁-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T₁ based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis.