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991.
Susana Teijeira Alfonso Teijeiro Roberto Fernández C. Navarro 《Acta neuropathologica》1998,96(5):481-486
The immunohistochemical expression of utrophin in 80 muscle biopsies from patients with dystrophinopathies and other neuromuscular
disorders is reported. All biopsy specimens were routinely studied by a battery of 12 histoenzymatic techniques, and immunohistochemistry
was performed for spectrin, three domains of dystrophin and two domains of utrophin. Abnormal utrophin expression was observed
in all dystrophinopathic muscles compared with normal controls or biopsy samples from several other muscular diseases. Inflammatory
myopathies presented abnormal overexpression of utrophin and an abnormal dystrophin immunolabeling pattern. This overexpression
of utrophin appears to be directly related to the decrease in dystrophin. We conclude that the study of utrophin is important
for the histological interpretation and differential diagnosis of dystrophin-related muscular disorders.
Received: 13 November 1997 / Revised: 6 February 1998, 20 May 1998 / Accepted: 22 May 1998 相似文献
992.
Fatty Acid Composition of Liver Total Lipids in Alcoholic Patients with and without Liver Damage 总被引:1,自引:0,他引:1
Maria Pia de la Maza Sandra Hirsch Susana Nieto Margarita Petermann Daniel Bunout 《Alcoholism, clinical and experimental research》1996,20(8):1418-1422
Alcohol ingestion may promote lipid peroxidation, and the presence of polyunsaturated fatty acids in liver lipids may be essential for the generation of liver damage through this mechanism. The aim of this study is to examine fatty acid composition of liver lipids in chronic alcoholics with and without histological liver damage. A percutaneous liver biopsy was performed to 28 patients hospitalized for treatment of their alcoholism. Liver total lipids were extracted from a portion of the tissue sample and fatty acid composition was measured by gas chromatography. Another piece of the sample was sent for histological study. Six patients had histological cirrhosis or alcoholic hepatitis in their biopsies, the rest of the patients had minimal changes. Patients with liver damage had higher levels of oleic acid and total monoenoic fatty acids, a higher 18:1/18:0 ratio, lower levels of polyunsaturated fatty acids, a lower 20:4/18:2 ratio, and a lower peroxidability index in liver total lipids, than patients without liver damage. Alcoholic patients with asymptomatic liver damage have less unsaturated fatty acids in liver total lipids than their counterparts with normal livers. 相似文献
993.
R Rial F j Serrano Fj M Vega R Rodriguez A Martin J Mendez R Mendez E Santos J Gallego 《European journal of vascular and endovascular surgery》2004,27(3):333-335
OBJECTIVES: The aim of this article is to report our experience in the use of a new technique for the treatment of type II endoleaks which appear after the endovascular treatment of abdominal aortic aneurysms. MATERIALS AND METHODS: In three patients with secondary type II endoleaks, we performed a translumbar puncture, introducing a 22-Gauge needle into the aneurysm sac under CT guidance. Once intrasac pressure had been registered, 1000U (2 ml) of human thrombin were slowly injected into the sac. RESULTS: Complete sealing of the endoleak was achieved in all three patients, confirmed by the lack of contrast filling of the sac in the CT scans performed 5 min and 24 h after the procedure. Initial intrasac pressure was equal to systolic arterial pressure in the three patients. After the procedure, the pressure decreased by 30-40 mmHg. There were no complications during the procedure, which lasted 45-90 min. No endoleak recurrence has been observed in any of the three cases 6 months later. CONCLUSIONS: We present an alternative method of treating type II endoleaks, which could become the treatment of choice if and when a wider experience confirms our initial good results. 相似文献
994.
Susana Navarro Nestor W Meza Oscar Quintana-Bustamante José A Casado Ariana Jacome Kimberly McAllister Silvia Puerto Jordi Surrallés José C Segovia Juan A Bueren 《Molecular therapy》2006,14(4):525-535
We have investigated the hematopoietic phenotype of mice with a hypomorphic mutation in the Brca2/Fancd1 gene (Brca2(Delta27/Delta27) mutation). In contrast to observations made in other Fanconi anemia (FA) mouse models, low numbers of hematopoietic colony-forming cells (CFCs) were noted in Brca2(Delta27/Delta27) mice, either young or adult. Additionally, a high incidence of spontaneous chromosomal instability was observed in Brca2(Delta27/Delta27) bone marrow (BM) cells, but not in Brca2(+/Delta27) or Fanca(-/-) BM cells. Although Brca2(Delta27/Delta27) CFCs were not hypersensitive to ionizing radiation, a very severe hematopoietic syndrome was observed in irradiated Brca2(Delta27/Delta27) mice. Conventional BM competition experiments showed a marked repopulation defect in Brca2(Delta27/Delta27) hematopoietic stem cells (HSCs), compared to wild-type HSCs. Moreover, we have observed for the first time in a DNA repair disease model a very significant proliferation defect in Brca2(Delta27/Delta27) HSCs maintained in their natural physiological environment. The progressive repopulation of wild-type HSCs transplanted into unconditioned Brca2(Delta27/Delta27) recipients is reminiscent of the somatic mosaicism phenomenon observed in a number of genetic diseases, including FA. The hematopoietic phenotype associated with the Brca2(Delta27/Delta27) mutation suggests that this FA-D1 mouse model will constitute an important tool for the development of new therapies for FA, including gene therapy. 相似文献
995.
996.
Pedro Monteiro Sónia Gala Susana Nobre Raquel Carreira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2005,24(1):53-61
Imidapril is an angiotensin I converting enzyme inhibitor, a class of drugs with known cardioprotective activity. It is now known that this is due not only to their antihypertensive activity, but also to the fact that they decrease cellular and tissue levels of angiotensin II, a potent vasoconstrictor and inducer of myocardial fibrosis. These mechanisms may explain the good clinical results of this class of drugs in the treatment of coronary artery disease and heart failure, two diseases whose etiopathogenesis is closely related to the activation of the renin-angiotensin-aldosterone system. However, the impact of this class of drugs on cardiac mitochondrial function during acute myocardial ischemia is still largely unknown. With the aim of studying the effect of imidapril on cardiac mitochondrial function during acute ischemia, we used an ex-vivo animal model, perfused in a Langerdorff system and then subjected to ischemia in the presence or absence of imidapril. We evaluated mitochondrial membrane electrical potential, respiratory chain O2 consumption, and rate and amplitude of mitochondrial swelling. We conclude that imidapril did not significantly change oxygen consumption by cardiac mitochondria, as assessed by the rate of respiratory state 3 (the state that corresponds to the active phosphorylation phase). However, imidapril significantly increased transmembrane electrical potential and, in ischemic cardiac mitochondria, was able to prevent the calcium-induced increase in the rate and amplitude of mitochondrial swelling, thus enabling better preservation of mitochondrial membrane structure, with consequent improvement of electrical potential after the phosphorylation cycle. These findings enabled a better understanding of the mechanisms behind the cytoprotection provided by imidapril during ischemic cardiomyopathy, clearly highlighting, at a cellular biology level, the importance of pharmacological modulation of cardiac mitochondrial function during acute ischemia. 相似文献
997.
Susana T L Chung 《Optometry and vision science》2004,81(7):525-535
PURPOSE: Crowding, the adverse spatial interaction due to proximity of adjacent targets, has been suggested as an explanation for slow reading in peripheral vision. The purposes of this study were to (1) demonstrate that crowding exists at the word level and (2) examine whether or not reading speed in central and peripheral vision can be enhanced with increased vertical word spacing. METHODS: Five normal observers read aloud sequences of six unrelated four-letter words presented on a computer monitor, one word at a time, using rapid serial visual presentation (RSVP). Reading speeds were calculated based on the RSVP exposure durations yielding 80% correct. Testing was conducted at the fovea and at 5 degrees and 10 degrees in the inferior visual field. Critical print size (CPS) for each observer and at each eccentricity was first determined by measuring reading speeds for four print sizes using unflanked words. We then presented words at 0.8x or 1.4x CPS, with each target word flanked by two other words, one above and one below the target word. Reading speeds were determined for vertical word spacings (baseline-to-baseline separation between two vertically separated words) ranging from 0.8x to 2x the standard single-spacing, as well as the unflanked condition. RESULTS: At the fovea, reading speed increased with vertical word spacing up to about 1.2x to 1.5x the standard spacing and remained constant and similar to the unflanked reading speed at larger vertical word spacings. In the periphery, reading speed also increased with vertical word spacing, but it remained below the unflanked reading speed for all spacings tested. At 2x the standard spacing, peripheral reading speed was still about 25% lower than the unflanked reading speed for both eccentricities and print sizes. Results from a control experiment showed that the greater reliance of peripheral reading speed on vertical word spacing was also found in the right visual field. CONCLUSIONS: Increased vertical word spacing, which presumably decreases the adverse effect of crowding between adjacent lines of text, benefits reading speed. This benefit is greater in peripheral than central vision. 相似文献
998.
Cohort studies include groups of patients that are followed over time to determine the incidence or natural history of a disease, together with the risk factors for specific outcomes. These studies can be used to determine disease characteristics as well as the causal relationship between exposure and disease. They are, however, very expensive, because they need large patient samples. Cohort studies can be classified as prospective (the investigator defines the sample and measures predictive variables before outcomes arise) or retrospective (the investigator defines the sample and measures predictive variables after outcomes arise). Cohort studies are susceptible to various types of bias (systematic errors) that must be eliminated in order to ensure the validity of the results. To increase the validity of cohort studies the investigator has to consider exposure, outcome, sample selection and the statistical analysis (risk ratios and/or differences, absolute and relative risks, etc.). 相似文献
999.
1000.
Superinfected cutaneous angiosarcoma: a highly malignant neoplasm simulating an inflammatory process
Carlos Diaz-Cascajo Maria de la Vega Agustin Rey-Lopez 《Journal of cutaneous pathology》1997,24(1):56-60
This report describes a patient with a poorly differentiated cutaneous angiosarcoma (CA) of the face superinfected with pseudomonas aeruginosa. Neoplastic cells were positive for CD-34, CD-31 and vimentin, whereas they failed to express other vascular markers such as Factor VIII and Ulex europeaus lectin. The tumor spread rapidly through the skin and the superficial soft tissue before metastasizing. The patient died of disease 6 months after histopathological diagnosis. An autopsy revealed widespread metastases in the lung and the liver. The aim of this report is to call attention to some circumstances in which CA may masquerade as an inflammatory process, delaying the right diagnosis with serious consequences for the patient. 相似文献