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21.
M. VILANOVA A. RIBEIRO J. CARNEIRO M. ARALA-CHAVES 《Scandinavian journal of immunology》1994,40(5):543-548
We describe here some immunomodulatory effects of thalidomide on autoimmune-prone mice. The highly increased synthesis of splenic IgM in NZB mice, of splenic and lymph node IgG of different subclasses in MRL/n mice, and of splenic and lymph node IgGl in MRL/lpr mice was markedly inhibited by thalidomide treatment. After a single treatment with 3mg of thalidomide, the following changes were observed in NZB mice: (i) an initial decrease in the numbers of large CD5+ μhigh , and in the numbers of total CD5+ μ− , CD5− μhigh , CD5+ μhigh lymphocyte populations of the pleural cavity followed by a late increase in the numbers of large cells of the three cell populations; (ii) a consistent increase in the numbers of a CD5low μlow pleural lymphoid population; (iii) a consistent reduction in the numbers of splenic large CD5+ B cells and an oscillatory increase in the number of cells with CD5− phenotype; (iv) a late reduction in the numbers of splenic total CD5+ B cells. These results are consistent with the notion that thalidomide controls a disease-associated expansion of B cells in autoimmune prone mouse strains through a stimulatory effect of the drug on the immune system. 相似文献
22.
Maša Davidović Nadine Zielonke Iris Lansdorp-Vogelaar Nereo Segnan Harry J. de Koning Eveline AM. Heijnsdijk 《Value in health》2021,24(3):353-360
ObjectivesTo quantify the impact of mammography-based screening on the quality of life, disability-adjusted life years (DALYs) averted or quality-adjusted life years (QALYs) gained can be used. We aimed to assess whether the use of DALYs averted or QALYs gained will lead to different cost-effective screening strategies.MethodsUsing the microsimulation model MISCAN, we simulated different breast cancer screening strategies varying in starting age (starting at 45, 47, and 50 years), stopping age (stopping at 69, 72, and 74 years), and frequency (annual [A], biennial [B], combination of both [A + B], and triennial [T]). In total, we defined 24 different breast cancer screening strategies, including no screening as a reference strategy. We calculated incremental cost-effectiveness ratios (ICERs) and compared which strategies were on the efficiency frontiers for DALYs and QALYs.ResultsBreast cancer screening averted between 46.00 and 105.58 DALYs and gained between 28.69 and 64.50 QALYs per 1000 women. For DALYs there were 5 strategies on the efficiency frontier (T50-69, T50-74, T45-74, B45-74, and A45-74). The same strategies plus one (B45-72) were on the efficiency frontier for QALYs.ConclusionsUsing DALYs averted instead of QALYs gained to assess the effects on quality of life from breast cancer screening in the Dutch population yields differences in ICERs, but almost the same strategies were on the efficiency frontiers. Whether the choice in outcome measure leads to a difference in optimal policy depends on the cost-effectiveness threshold. 相似文献
23.
Rufino M. Silva J. R. Faria de Abreu J. G. Cunha-Vaz 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(11):721-726
Background: Extensive clinical studies on retinal branch vein occlusion have not yet been able to clarify its pathogenesis. A study designed to look at the associated blood-retina barrier changes may contribute to a better understanding of the different forms of evolution of this pathology. Methods: A prospective study was done in seven patients with recent large temporal branch vein occlusion. Vitreous fluorophotometry, fluorescein angiography and retinal colour photography were performed within the 1st week after the onset of symptoms, 1 week later, and at 12 and 24 weeks. Results: A more marked blood-retina barrier breakdown was found at 1, 2, 12 and 24 weeks in the eyes that later developed extensive capillary non-perfusion. Conclusions: Our results suggest that the breakdown of the blood-retina barrier may play an important role in the subsequent development of retinal nonperfusion in eyes with large branch vein occlusion. We postulate that the eyes that will present later extensive capillary nonperfusion develop, from the initial stages of the disease, a progressive ischaemic capillaropathy characterized by blood-retina barrier breakdown. Retinal pigment epithelium degeneration and arterial lumen narrowing, secondary to the vein obstruction, may help to increase and perpetuate the blood-retina barrier breakdown during the first 6 months after the occlusion. 相似文献
24.
Novel imaging techniques for diabetic macular edema 总被引:2,自引:0,他引:2
Lobo C Bernardes R Faria de Abreu JR Cunha-Vaz JG 《Documenta ophthalmologica. Advances in ophthalmology》1999,97(3-4):341-347
Retinal edema should be defined as any increase of water of the retinal tissue resulting in an increase in its volume. It
may be of cytotoxic or vasogenic origin. Development of vasogenic macular edema is dependent on a series of factors such as
blood pressure, blood-retinal barrier permeability, retinal cell damage, retinal tissue osmotic pressure and retinal tissue
compliance. Objective measurements of retinal thickness are now possible using the Retinal Thickness Analyser. Localised measurements
of blood-retinal barrier permeability may also be obtained using the Retinal Leakage Analyser, a modified confocal scanning
laser fluorometer, while obtaining simultaneously angiographic images of the choroid and retina. These new imaging techniques
show that cytotoxic and vasogenic retinal edema may occur independently in the early stages of diabetic retinopathy. These
findings offer new perpectives for designing novel therapeutic strategies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
25.
Welzl-Hinterkörner E Thölen H Stürmer J Opravil M Bernauer W 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(2):87-91
Background: Cystoid macular edema (CME) in AIDS patients with inactive cytomegalovirus (CMV) retinitis is an uncommon but potentially
sight-threatening complication. The pathogenesis of CME in these patients is unclear. This study tries to identify possible
risk factors by analyzing the charts of five patients.
Methods: Ten eyes of 5 patients that finally developed CME were followed for an average of 18 months. The initial retinal lesions,
their response to antiviral treatment, the development of CME, and the patients' immune status were prospectively monitored.
Results: CMV retinitis was diagnosed at a median CD4+ count of 3 cells/mm3 (range 0–11). All eyes responded to the initial systemic anti-viral treatment. At the onset of CME, CMV retinitis was controlled
by antiviral maintenance therapy in all patients [ganciclovir (n = 2), cidofovir (n = 2), foscarnet (n = 1)]. The median time between diagnosis of CMV retinitis and onset of CME was 11.5 months (range 5–24). Development of CME
was associated with significant visual loss: acuity ranged from 0.05 to 0.7 when CME was first noticed, compared to 0.8–1.25
at diagnosis of CMV retinitis. Duration of inflammation, size or zone of retinal necrosis did not favor the development of
CME, neither did the antiviral therapy. A weak correlation of CME development and immune status (expressed as increase of
CD4+ cells) was found. Due to systemic corticosteroids CME resolved.
Conclusions: CME is a new visual threat to AIDS-patients with CMV retinitis whose immune status improved under the latest combined antiretroviral
therapy. Therapy with oral corticosteroids may positively influence this condition.
相似文献
26.
Friedrichs GS Abreu JN Cousins GR Chi L Borlak J Lucchesi BR 《Journal of cardiovascular pharmacology and therapeutics》1996,1(4):313-324
BACKGROUND: The electrophysiologic and antifibrillatory properties of tedisamil (KC-8857;3,7-di-(cyclopropylmethyl)-9,9-tetramethylene-3,7-diazabicyclo[3.3.1]-nonane dihydrochloride) were studied in a conscious canine model of sudden cardiac death. METHODS AND RESULTS: Three to five days after surgically induced myocardial infarction (2-hour occlusion of the left anterior descending coronary artery), animals were subjected to programmed electrical stimulation to identify those at risk for ischemia-induced ventricular fibrillation. Sixty minutes after tedisamil (10 mg/kg, administered orally) PES was repeated. Tedisamil increased the ventricular effective refractory period from 106 +/- 6 to 134 +/- 7 ms (P <.05) compared to placebo treatment, which did not alter the ERP (123 +/- 6 to 116 +/- 5 ms). Tedisamil prolonged the QTc interval, from a predrug value of 308 +/- 14 to 327 +/- 14 ms, postdrug. The extent of the surgically induced anterior wall myocardial infarct did not differ between groups, tedisamil, 29 +/- 2%, and placebo, 28 +/- 2% of the left ventricle. CONCLUSIONS: Tedisamil conferred protection against ischemia induced ventricular fibrillation; 7 of 10 tedisamil-treated dogs survived, compared to 4 of 14 surviving in the vehicle treated group (P <.05). Although we observed instances of vomiting and/or diarrhea in several dogs after a single oral administration of tedisamil, the data indicate that oral administration of tedisamil provides protection from ischemia-induced ventricular fibrillation in the postinfarcted conscious canine. The mechanism by which tedisamil achieves its antifibrillatory effect may be related to its ability to prolong the ERP of the ventricular myocardium without altering ventricular conduction velocity. 相似文献
27.
Peter J Harris Siriphun Hiranyachattada Arianne M Antoine Lesley Walker Angela M Reilly Eveline Eitle 《Clinical and experimental pharmacology & physiology》1996,23(Z3):112-118
- 1 The effects of angiotensin II (AngII) on water and electrolyte transport are biphasic and dose-dependent, such that low concentrations (10?12 to 10?9 mol/L) stimulate reabsorption and high concentrations (10?7 to 10?6 mol/L) inhibit reabsorption. Similar dose-response relationships have been obtained for luminal and peritubular addition of AngII.
- 2 The cellular responses to AngII are mediated via AT1 receptors coupled via G-regulatory proteins to several possible signal transduction pathways. These include the inhibition of adenylyl cyclase, activation of phospholipases A2, C or D and Ca2+ release in response to inositol-1,4,5,-triphosphate or following Ca2+ channel opening induced by the arachidonic acid metabolite 5,6,-epoxy-eicosatrienoic acid. In the brush border membrane, transduction of the AngII signal involves phospholipase A2, but does not require second messengers.
- 3 Angiotensin II affects transepithelial sodium transport by modulation of Na+/H+ exchange at the luminal membrane and Na+/HCO3 cotransport, Na+/K+-ATPase activity and K+ conductance at the basolateral membrane.
- 4 Atrial natriuretic factor (ANF) does not appear to affect proximal tubular sodium transport directly, but acts via specific receptors on the basolateral and brush border membranes to raise intracellular cGMP levels and inhibit AngII-stimulated transport.
- 5 It is concluded that there is a receptor-mediated action of ANF on proximal tubule reabsorption acting via elevation of cGMP to inhibit AngII-stimulated sodium transport. This effect is exerted by peptides delivered at both luminal and peritubular sides of the epithelium and provides a basis for the modulation by ANF of proximal glomerulotubular balance. The evidence reviewed supports the concept that in the proximal tubule, AngII and ANF act antagonistically in their roles as regulators of extracellular fluid volume.
28.
29.
Coexistence of benign phyllodes tumor and invasive ductal carcinoma in distinct breasts: case report
Guerino Barbalaco Neto Claudia Rossetti Natalia A Souza Fernando LA Fonseca Ligia Ajaime Azzalis Virginia Berlanga Campos Junqueira Vitor E Valenti Luiz Carlos de Abreu 《European journal of medical research》2012,17(1):8
This report describes a rare case of coexistence of benign phyllodes tumor, which measured 9 cm in the right breast, and invasive ductal carcinoma of 6 cm in the left breast, synchronous and independent, in a 66-year-old patient. The patient underwent a bilateral mastectomy due to the size of both lesions. Such situations are rare and usually refer to the occurrence of ductal or lobular carcinoma in situ when associated with malignant phyllodes tumors, and more often in ipsilateral breast or intra-lesional. 相似文献
30.
Gabriella Martillotti Mario Talajic Eveline Rey Line Leduc 《Journal d'obstetrique et gynecologie du Canada》2012,34(11):1073-1076
BackgroundPatients with congenital long QT syndrome (LQTS) are at increased risk of ventricular arrhythmia, particularly during labour and the puerperium.CaseA 28-year-old primigravida with known LQTS underwent induction of labour at 41 weeks’ gestation using a Foley catheter balloon and IV oxytocin. Vaginal delivery with passive second stage and outlet forceps was undertaken with early epidural analgesia to prevent tachycardia and psychological stress. The patient gave birth to a healthy female, and had an uncomplicated postpartum period under continuous electrocardiogram monitoring.ConclusionVaginal delivery with use of oxytocin for the induction of labour can be safely undertaken in patients with LQTS. 相似文献