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A. B. Soares P. R. Faria L. A. Magna M. E. P. Correa C. A. de Sousa O. P. Almeida M. L. Cintra 《Journal of oral pathology & medicine》2005,34(6):368-373
BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease. 相似文献
13.
Jocivania O da Silva Renata S Fernandes Fábio K Ticli Clayton Z Oliveira Maurício V Mazzi Jo?o J Franco Silvana Giuliatti Paulo S Pereira Andreimar M Soares Suely V Sampaio 《Toxicon》2007,50(2):283-291
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies. 相似文献
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K Nakayama Y Nemoto Y Inoue T Mochizuki S B Soares Jr K Ohata J Katsuyama Y Onoyama K Wakasa 《AJNR. American journal of neuroradiology》1997,18(2):331
Cranial malignant fibrous histiocytomas are rare tumors. Most are hypervascular, destructive masses that are similar to other malignant lesions and to malignant fibrous histiocytomas found elsewhere in the body. We describe a myxoid malignant fibrous histiocytoma of the temporal bone, possibly of dural origin, with features that more closely resembled a meningioma at CT, MR imaging, and angiography. 相似文献
16.
Reduction in temporal N-acetylaspartate and creatine (or choline)
ratio in temporal lobe epilepsy: does this 1H-magnetic
resonance spectroscopy finding mean poor seizure control? 总被引:1,自引:0,他引:1
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J. Mendes-Ribeiro R. Soares F. Simoes-Ribeiro M Guimaraes 《Journal of neurology, neurosurgery, and psychiatry》1998,65(4):518-522
BACKGROUND—Proton magnetic resonance spectroscopy(1H-MRS) is a potentially useful tool in the in vivoinvestigation of brain metabolites in intractable temporal lobeepilepsy (TLE). Focal N-acetylaspartatate (NAA) reductions have beencorrelated with mesial temporal sclerosis (MTS) in surgically resectedepileptogenic foci.
OBJECTIVE—To evaluate the abnormalities in themetabolites NAA, creatine+ phosphocreatine (Cr), and cholinecontaining compounds (Cho) in the temporal lobe of medically refractorypatients with temporal lobe epilepsy, seizure free patients withtemporal lobe epilepsy, and normal controls.
PATIENTS AND METHODS—Ten refractory patients, 12 seizure free patients with temporal lobe epilepsy, and 10 age matchednormal controls were studied by 1H-magnetic resonancespectroscopy. All patients had consistently unilateral temporal EEGabnormalities and a normal brain MRI. Proton MR spectra were obtainedfrom an 8 ml volume in the medial temporal lobes in patients withtemporal lobe epilepsy (ipsilateral to EEG foci) and the normalcontrols. The signals measured were expressed in terms of NAA/Cr,NAA/Cho, and Cho/Cr.
RESULTS—When compared with seizure free patientswith temporal lobe epilepsy and normal controls, the 10 refractorypatients with temporal lobe epilepsy had a lower mean (SEM) NAA/Crratio (1.65(0.53) v 2.62 (0.60), and 2.66 (0.73);p<0.002 and p<0.006) and a lower mean NAA/Cho ratio (1.59 (0.79)v 2.83 (1.33) and 2.58(0.67); p<0.02 andp<0.007).Furthermore, the two patients showing the lowest NAA/Cr ratios (1.47 and 1.73) in the seizure free group had had a past period of poorseizure control.
CONCLUSIONS—There were reduced temporal NAA/Cr andNAA/Cho ratios, suggesting neuronal loss or damage, associated withpast or present poor seizure control in the patients with temporal lobeepilepsy, but it does not exclude the possibility of a future completeseizure control (seizure free patients with temporal lobe epilepsy at the time of 1H-MRS). This study warrants further1H-MRS investigation with a larger series of patients withtemporal lobe epilepsy.
相似文献
OBJECTIVE—To evaluate the abnormalities in themetabolites NAA, creatine+ phosphocreatine (Cr), and cholinecontaining compounds (Cho) in the temporal lobe of medically refractorypatients with temporal lobe epilepsy, seizure free patients withtemporal lobe epilepsy, and normal controls.
PATIENTS AND METHODS—Ten refractory patients, 12 seizure free patients with temporal lobe epilepsy, and 10 age matchednormal controls were studied by 1H-magnetic resonancespectroscopy. All patients had consistently unilateral temporal EEGabnormalities and a normal brain MRI. Proton MR spectra were obtainedfrom an 8 ml volume in the medial temporal lobes in patients withtemporal lobe epilepsy (ipsilateral to EEG foci) and the normalcontrols. The signals measured were expressed in terms of NAA/Cr,NAA/Cho, and Cho/Cr.
RESULTS—When compared with seizure free patientswith temporal lobe epilepsy and normal controls, the 10 refractorypatients with temporal lobe epilepsy had a lower mean (SEM) NAA/Crratio (1.65(0.53) v 2.62 (0.60), and 2.66 (0.73);p<0.002 and p<0.006) and a lower mean NAA/Cho ratio (1.59 (0.79)v 2.83 (1.33) and 2.58(0.67); p<0.02 andp<0.007).Furthermore, the two patients showing the lowest NAA/Cr ratios (1.47 and 1.73) in the seizure free group had had a past period of poorseizure control.
CONCLUSIONS—There were reduced temporal NAA/Cr andNAA/Cho ratios, suggesting neuronal loss or damage, associated withpast or present poor seizure control in the patients with temporal lobeepilepsy, but it does not exclude the possibility of a future completeseizure control (seizure free patients with temporal lobe epilepsy at the time of 1H-MRS). This study warrants further1H-MRS investigation with a larger series of patients withtemporal lobe epilepsy.
相似文献
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18.
Claudio Babiloni Giuliano Binetti Emanuele Cassetta Gloria Dal Forno Claudio Del Percio Florinda Ferreri Raffaele Ferri Giovanni Frisoni Koichi Hirata Bartolo Lanuzza Carlo Miniussi Davide V Moretti Flavio Nobili Guido Rodriguez Gian Luca Romani Serenella Salinari Paolo M Rossini 《Clinical neurophysiology》2006,117(2):252-268
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD. 相似文献
19.
W W Campbell M M Polansky N A Bryden J H Soares R A Anderson 《The Journal of nutrition》1989,119(4):653-660
The effects of exercise training and dietary chromium intake on rat liver and muscle glycogen metabolism, tissue and body weight and feed consumption were examined. After 16 wk of training, liver, gastrocnemius and biceps femoris glycogen concentrations were higher in the trained compared to sedentary groups, independent of dietary chromium. There was a chromium x training interaction on glycogen synthase activities in the liver and gastrocnemius muscle. Liver glycogen phosphorylase activities (expressed per g liver) were lower in the chromium-supplemented rats as compared to the non-supplemented rats after 5 wk of dietary treatment, but were similar after 8 wk and higher after 18 wk. Gastrocnemius phosphorylase activity (expressed per mg protein) was lower in the trained rats as compared to the sedentary rats after 16 wk, independent of dietary chromium. Biceps femoris phosphorylase activities were not altered due to training or dietary chromium. Total protein concentration increased in the liver but decreased in the gastrocnemius due to dietary chromium. In summary, liver glycogen synthase and phosphorylase activities were dependent upon dietary chromium. Dietary chromium altered gastrocnemius synthase, but not phosphorylase activities. Changes in enzyme activities may be related to the chromium-dependent effects on liver protein and the chromium and training-dependent effects on gastrocnemius total protein. 相似文献
20.
Endocytosis was studied at the ultrastructural level in different developmental forms ofTrypanosoma cruzi after incubation of the parasites in the presence of gold-labeled proteins (albumin-Au, peroxidase-Au and transferrin-Au) and low-density lipoprotein (LDL-Au). Epimastigote (culture) forms actively ingested LDL and proteins. Initially, gold particles were seen adhering only to the cytostome and inside the flagellar pocket. In parasites incubated at 4°C with transferrin-Au or peroxidase-Au, labeling was found only at these two sites, showing that receptor-mediated endocytosis occurs in both regions. In the cytoplasm, gold particles were seen only inside two different compartments: membrane-bound vesicles and reservosomes. Incubation of epimastigotes with acridine orange followed by fluorescence microscopy revealed intense orange staining, indicating that the reservosomes have an acidic pH. This staining was abolished after incubation of the parasites in the presence of ammonium chloride. These data confirm that this compartment is the site of accumulation of ingested lipids and proteins. Little intracellular labeling with transferrin-Au was found in in vitro — derived amastigotes and trypomastigotes (both lack reservosomes). However, although in amastigotes very few gold particles were seen bound to the cells, in trypomastigotes they were observed bound to the membrane that encloses the cell body, the flagellar pocket, and the flagellum, suggesting that the receptors are more abundant in this form. 相似文献