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21.
Photodynamic therapy (PDT) is being investigated as an alternative treatment modality in cancer treatment. It has been shown to induce tumor hypoxia and upregulation of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF). The objective of this study was to improve in vivo tumor growth control of nasopharyngeal carcinoma (NPC), treated at a subcurative dosage by using a combination of Hypericin-PDT and COX-2 inhibitor, Celebrex (CX). The effect of an initial CX dose at 6- and 24-h post-PDT was investigated simultaneously. It was observed that hypoxic NPC/CNE2 cells upregulate both COX-2 and VEGF A genes in vitro. In vivo studies, down-regulation of COX-2 and hypoxia inducible factor-1alpha (HIF-1alpha) genes at 24-h post-PDT and bulk tumor ablation at 48-h post-PDT was observed. However, 24-28 days later regrowth was observed. In a combination treatment, 1st CX dose at 6-h post-PDT had the highest tumor control in which tumors were 相似文献   
22.
Two hundred and twenty five patients of Takayasu's arteritis were studied over 13 years. Male:Female ratio was 1:7. Mean age of the study population was 19 +/- 4 years. Of these 225 patients, 75 patients had symptoms and/or signs of cardiac involvement and these patients were subjected to coronary angiography. Significant coronary artery occlusion (i.e. more than 50% narrowing of luminal diameter) was present in 9 patients. Incidence of coronary artery lesions in Takayasu's arteritis is 12% in this study. The proximal segments of coronary arteries were involved while the distal segments were spared. Out of 34 patients with angina pectoris, only 3 patients had significant coronary arterial narrowing.  相似文献   
23.
The present study was undertaken to examine the T-lymphocyte activation in IgA nephropathy. Serum-soluble interleukin 2 receptor (sIL2R) levels were studied in 29 IgA nephritic patients, 17 patients with chronic glomerulonephritis (non-IgA nephropathy), and 30 healthy controls during an infection-free period. No difference in serum sIL2R level was demonstrated among these three groups of subjects. However, the serum sIL2R levels of IgA nephritic patient rose significantly during clinical exacerbation with synpharyngitic macroscopic hematuria and the serum sIL2R levels fell when hematuria subsided. Mitogen-stimulated cellular interleukin 2 receptor (IL2R) expression, sIL2R release, and interleukin 2 (IL2) production were also examined in peripheral blood mononuclear cells (PBMC) cultured for 24–48 hr in 21 patients with IgA nephropathy, 17 patients with chronic glomerulonephritides, and 17 healthy controls. The total cellular IL2R expression and sIL2R release did not differ among these three groups of subjects. However, the individual T-cell subsets bearing IL2R were distinctly different between IgA nephritic patients and the other two groups of controls. IgA nephritic patients had increased activated CD4+ lymphocytes and reduced activated CD8+ lymphocytes. Furthermore, IL2 production in response to phytohemagglutinin and pokeweed mitogen stimulation was increased in lymphocytes from patients with IgA nephropathy. The IL2 production did not correlate with the quantities of cellular and sIL2R yet the cellular IL2R expression paralleled the sIL2R released by cultured lymphocytes. Our present study suggests that the T lymphocytes from patients with IgA nephropathy have a defect in overproduction of IL2 and increased activated T helper-cell subset upon mitogenic stimulation. Serum measurement of sIL2R could potentially be useful in monitoring the disease activity.  相似文献   
24.
We investigated whether object recognition memory is modulated by estrogen in young (5 month) and aged (24 month) female C57Bl/6J mice, and if cholinergic muscarinic receptors might contribute to this response. Mice that were ovariectomized, or ovariectomized plus estradiol-treated three weeks before behavioral testing or quantitative autoradiography were compared to intact mice. Memory for a previously encountered object deteriorated significantly between 3 and 6h after initial exposure, regardless of animal age. In both young and aged mice, estradiol-treated mice showed significantly greater recall than did ovariectomized mice. In both age groups, the apparent number of [(3)H]pirenzepine/M(1)-like and [(3)H]AFDX384/M(2)-like muscarinic receptor binding sites was reduced in the basal forebrain as well as its projection areas following ovariectomy, but this decrease was not alleviated by estrogen. Aging poorly affected object memory, but reduced muscarinic binding in some cortical subregions and in the caudate nucleus. These findings suggest that estrogen effects on memory in C57Bl/6J mice are not due to changes in the number of muscarinic receptors.  相似文献   
25.
In recent years, the indications for permanent pacemakers have expanded. The interest has focussed on hypertrophic cardiomyopathy, dilated cardiomyopathy and a new entity called hypertensive hypertrophy with cavity obliteration (HHCO). Pacemaker therapy is establishing itself for the prevention of atrial fibrillation. Pacing for neurocardiogenic syncope with newer pacing mode has encouraging datas. Pacemaker for long QT syndrome, after cardiac transplant and for haemodynamic improvement in occasional cases of first degree atrio-ventricular block is getting attention. The AHA and ACC guidelines updated in 1998 for implantation of cardiac pacemakers, now include several of these newer indications.  相似文献   
26.
27.
The neuropathological features associated with Alzheimer's disease (AD) brain include the presence of extracellular neuritic plaques composed of amyloid beta protein (Abeta), intracellular neurofibrillary tangles containing phosphorylated tau protein and the loss of basal forebrain cholinergic neurons which innervate regions such as the hippocampus and the cortex. Studies of the pathological changes that characterize AD and several other lines of evidence indicate that Abeta accumulation in vivo may initiate phosphorylation of tau protein, which by disrupting neuronal network may trigger the process of neurodegeneration observed in AD brains. However, the underlying cause of degeneration of the basal forebrain cholinergic neurons and their association, if any, to Abeta peptides or phosphorylated tau remains mostly unknown. In the present study, using rat primary septal cultures, we have shown that aggregated Abeta peptides, in a time (18-96 h)- and concentration (0.7-60 microM)-dependent manner, induce toxicity and decrease choline acetyltransferase enzyme activity in cultured neurons. Using immunocytochemistry and immunoblotting, we have also demonstrated that Abeta treatment can significantly increase the phosphorylation of tau protein in septal cultures. At the cellular level, hyperphosphorylated tau is mostly apparent in the somatodendritic compartment of the neurons. Abeta peptide (10 microM), in addition to tau phosphorylation, also activates mitogen-activated protein kinase and glycogen synthase kinase-3beta, the two kinases which are known to be involved in the formation of hyperphosphorylated tau in the AD brain. Exposure to specific inhibitors of the mitogen-activated protein kinase (i.e. PD98059) or glycogen synthase kinase-3beta (i.e. LiCl) attenuated the hyperphosphorylation of the tau protein in cultured neurons.Given the evidence that tau phosphorylation can induce cell loss by disrupting neuronal cytoskeleton, it is likely that aggregated Abeta peptide triggers degeneration of septal neurons, including those expressing the cholinergic phenotype, by phosphorylation of the tau protein activated by mitogen-activated protein kinase and glycogen synthase kinase-3beta. These results, taken together, suggest that cultured septal cholinergic neurons are vulnerable to Abeta-mediated toxicity and tau phosphorylation may play an important role in Abeta-induced neurodegeneration.  相似文献   
28.
1. Extracellular single neuron activity was recorded in the lateral hypothalamic area (LHA) of awake, behaving monkeys, with particular regard to the feeding-related functional characteristics of glucose-sensitive (GS) versus glucose-insensitive (GIS) neurons. Firing rate changes were recorded by means of carbon fiber, multibarreled glass microelectrodes during 1) microelectrophoretic application of various chemicals, 2) gustatory and olfactory stimulation, and 3) a high fixed-ratio schedule (FR) bar press feeding task. 2. In 336 neurons examined, 91 (27%) were suppressed by electrophoretically administered glucose, and so they were designated as GS cells. The 245 neurons (73%) in which the firing rates did not change during glucose applications were pronounced GIS. The 179 GS and GIS cells tested exhibited different responses to the catecholamines (CAs), noradrenaline (NA) and dopamine (DA), both of which are intimately involved in the control of feeding. More GS neurons responded to NA than did GIS cells; the predominant effect of both CAs on GS neurons was inhibition. 3. The taste responsiveness of 111 LHA neurons was examined. Fifty-seven cells (52%) showed responses to gustatory stimulation. Of 50 GS neurons tested, 33 (66%) exhibited firing rate changes to tastes. On the contrary, only 24 (39%) of the 61 GIS neurons examined responded to gustatory stimuli. Activity changes of GS neurons commonly occurred to two or more tastants, in distinction to the relative gustatory specificity shown by GIS cells. 4. Two hundred fifty-six (84%) of the 303 neurons tested responded during one or more phases of the bar press feeding task. Most activity changes occurred during the bar press (BP) and reward (RW) periods, however numerous phasic responses to cue light (CL) and cue tone (CT) were also observed. A higher proportion of the GS neurons showed task-related activity changes than did the GIS cells (77, 95% and 179, 81%, respectively). GS neurons responded more during the BP phase and to the food reward; GIS cells were more responsive during the CL that enabled acquisition and the CT that signaled reward. Thus GS neurons were responsive during the acquisition and consumption of reward, whereas GIS cells responded to external cues signaling both of these events. The gustatory neurons displayed specific task-related activity changes only in the CL (GIS cells) and BP phases (GS neurons), that is, in phases most intimately involved in sensory-motor integration. 5. Two-thirds of the 30 GS neurons tested were responsive to both gustatory and olfactory stimulation as opposed to only one-third of GIS cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
29.
The critical role of macrophage migration inhibitory factor (MIF) in mediating inflammatory lung injury in acute respiratory distress syndrome (ARDS) has been raised recently. The present study has identified enhanced MIF protein expression in alveolar capillary endothelium and infiltrating macrophages in lung tissues from ARDS patients. The possibility that MIF up-regulates its synthesis in an autocrine fashion in ARDS was tested using cultured endothelial cells stimulated with MIF and a murine model of lipopolysaccharide (LPS)-induced acute lung injury. MIF induced significant MIF and tumour necrosis factor (TNF)-alpha synthesis in cultured endothelial cells and the effect was blocked by neutralizing anti-MIF antibody. A similar blocking effect was observed when MIF-stimulated endothelial cells were pretreated with neutralizing anti-TNF-alpha antibody or glucocorticoid, supporting the notion that MIF induced TNF-alpha production via an amplifying pro-inflammatory loop. Treatment with anti-MIF or glucocorticoid effectively attenuated pulmonary pathology and the synthesis of MIF or TNF-alpha in mice with LPS-induced acute lung injury. Mildly augmented expression of aquaporin 1 (AQP1) was also detected in alveolar capillary endothelium in ARDS. In vitro studies revealed that both MIF and TNF-alpha induced a small increase of AQP1 synthesis in cultured endothelial cells. These findings suggest that MIF plays a crucial pathological role leading to alveolar inflammation in ARDS. Anti-MIF and early glucocorticoid therapy may represent a novel therapeutic approach for reducing alveolar inflammation in ARDS.  相似文献   
30.
The efficacy and safety of amoxicillin plus clavulanic acid was compared with that of amoxicillin, erythromycin and co-trimoxazole in an open label, randomized trial in 50 children in each group (total 200) with mild to severe pyodermas. Majority (47%) had impetigo. Fifty (25%) children had mild pyoderma, 56 (28%) had moderate and 94 (47%) children had severe pyoderma. Pure growth of S aureus was isolated in 130 (65%) children, S pyogenes in 42 (21%) and both organisms in 28 (14%) children. In mild to moderate pyoderma either of the drug tried was equally effective. In severe pyoderma, 24 of twenty five (96%) children receiving amoxicillin plus clavulanic acid, 18 of twenty (90%) children in amoxicillin group, 20 of twenty four (83.3%) children in erythromycin group and 13 of twenty five (52%) children in co-trimoxazole group showed clinical cure of therapy. Amoxicillin combined with clavulanic acid was well tolerated in children and there was no significant side effect except mild diarrhoea in two cases (4%) which was well controlled by taking the drug with meals.  相似文献   
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