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991.
Soluble adhesion molecules and cytokines in patients with myasthenia gravis treated by plasma exchange 总被引:5,自引:0,他引:5
Plasma exchange (PE) is an effective therapeutic method used in patients with myasthenia gravis (MG) refractory to common therapy and/or with life-threatening respiratory complications. Except for acetylcholine receptor antibodies (AChRAbs), some other inflammatory mediators possibly activated in MG may also be removed during PE. Serum levels of soluble adhesion molecules (sICAM-1 and sVCAM-1), IL-6 and soluble receptors for IL-2 (sIL-2R), IL-6 (sIL-6R) and TNF alpha (sTNF-R II) were measured in 20 MG patients assigned to treatment with PE. On the basis of the serum levels of AChRAb the patients were subdivided into 2 groups (8 patients with low AChRAb, 12 patients with high AChRAb). Soluble adhesion molecules and cytokines were measured before the first and last PE, at the end of the first PE and in the samples of plasma filtrate obtained during the first PE. Before the first PE patients with MG had higher serum levels of sICAM-1, sVCAM-1, sIL-2R and sTNF-R II than controls. Both after the first PE and during the course of PE, a substantial decrease in serum levels of AChRAb, sICAM-1 and sVCAM-1 was recorded. However, serum levels of sIL-2R and sTNF-R II were not significantly influenced by either a single treatment or during the course of PE. There were high levels of AChRAb, soluble adhesion molecules and soluble cytokine receptors in plasma filtrates too. Patients with high circulating AChRAb had higher serum levels of sICAM-1 and sVCAM-1 than patients with low AChRAb. Increased serum levels of soluble adhesion molecules and soluble cytokine receptors in patients with MG suggest some systemic activation of the immune response which is more pronounced in patients with high circulating AChRAb. PE led to the decrease in serum AChRAb and soluble adhesion molecules due to their effective filtration but, on the other hand, serum levels of soluble cytokine receptors were not influenced by PE, in spite of their effective filtration which is probably counteracted by their increased production, possibly stimulated by the contact of the blood with the synthetic membrane. 相似文献
992.
Canto P de la Chesnaye E López M Cervantes A Chávez B Vilchis F Reyes E Ulloa-Aguirre A Kofman-Alfaro S Méndez JP 《The Journal of clinical endocrinology and metabolism》2000,85(5):1908-1911
In Ullrich-Turner syndrome (UTS) patients, the presence of a Y-chromosome or Y-derived material has been documented in frequencies ranging from 4-61%. Mutations of SRY (testis-determining gene) constitute the cause of XY sex reversal in approximately 10-15% of females with pure gonadal dysgenesis. Most of these mutations have been described in the HMG (high mobility group) box of the gene, which is the region responsible for DNA binding and bending; however, various mutations outside the HMG box have been reported. We carried out molecular studies of the SRY gene in three patients with a UTS phenotype and bilateral streaks; two presented a 45,X/46,XY mosaic, and the third a Y marker chromosome. In two patients a missense mutation, S18N, was identified in the 5' non-HMG box region in DNA from blood and both streaks; this mutation was not identified in 75 normal males. Sequencing of the DNA region of interest was normal in the father and older brother of patient 1, demonstrating that in this patient the mutation was de novo. A previous report of a 46,XY patient with partial gonadal dysgenesis who presented the same mutation as our patients indicates the probable existence of a hot spot in this region of the SRY gene and strengthens the possibility that all gonadal dysgeneses constitute part of a spectrum of the same disorder. It also demonstrates that a single genetic abnormality can result in a wide range of phenotypic expression. 相似文献
993.
Costa A Bescós M Velho G Chêvre J Vidal J Sesmilo G Bellanné-Chantelot C Froguel P Casamitjana R Rivera-Fillat F Gomis R Conget I 《European journal of endocrinology / European Federation of Endocrine Societies》2000,142(4):380-386
OBJECTIVE: To investigate the frequencies of the major maturity-onset diabetes of the young (MODY) subtypes in a panel of Spanish families and to assess phenotypic differences in patients with the different subtypes of MODY. METHODS: Forty-eight subjects from twenty families with clinical diagnosis of MODY were studied. They underwent a standardised clinical examination and a 75-g oral glucose tolerance test (OGTT) was performed. Estimations of insulin sensitivity (%S) and insulin secretion capacity (%B) were calculated by the computer-solved homeostasis model assessment (HOMA). Mutations in the coding regions of hepatocyte nuclear factor (HNF)-4alpha/MODY1, glucokinase (GCK/MODY2) and HNF-1alpha/MODY3 genes were investigated by single strand comformation polymorphism and sequencing analysis. RESULTS: Mutations in the GCK and HNF-1alpha genes were observed in 5 (25%) and 7 (35%) families respectively. Novel mutations included R385X, M238fsdelT, V226fsdelTinsAA and S418-7del11 in the GCK gene, and S121fsdelC, V133M, R159Q and V259D in the HNF-1alpha gene. No MODY1 families were found. Subjects which were neither MODY2 nor MODY3 (MODY-X) had a higher fasting glucose than subjects in the other groups. Insulin secretion capacity was similar in the three groups and the insulin sensitivity was decreased in MODY-X subjects. Glucose levels were significantly higher and insulin levels significantly lower, throughout the OGTT, in MODY3 compared with MODY2 subjects. CONCLUSIONS: Mutations in the GCK/MODY2 and HNF-1alpha/MODY3 genes account for the majority of cases in a panel of Spanish MODY families, with MODY3 being the most frequent subtype. The relative frequencies and the clinical characteristics of these MODY subtypes are in agreement with data previously reported in other European populations. MODY-X patients seem to present a heterogeneous clinical profile. 相似文献
994.
Rangel A Basave M Lavalle C Hernández L Ochoa J Chávez E Albarrán H 《Archivos del Instituto de Cardiología de México》2000,70(1):66-71
This is the case of a 27 years-old woman with signs and symptoms of severe untreatable congestive heart failure, anemia, gingival mucosa ulcers, photosensitivity and alopecia. The electrocardiographic, echocardiographic, angiographic and hemodynamic data oriented the diagnosis of restrictive cardiomyopathy, mitral insufficiency secondary to mitral prolapse and bi-atrial dilation. The histologic study of the endomyocardial biopsy, performed during catheterization, showed signs of endomyocardial fibrosis, and immunological analysis was compatible with systemic lupus erythematosus. As far as we know, this is the first case of endomyocardial fibrosis (Davies disease) associated with systemic lupus erythematosus published in the medical literature. The etiology of Davies disease remains unrevealed and its association with systemic lupus erythematosus suggest a probable autoimmune origin. 相似文献
995.
Pascual Figal DA Valdés Chávarri M Ruipérez JA Cortés R López Pálop R Picó Aracil F García Alberola A 《Revista espa?ola de cardiología》2000,53(6):791-796
INTRODUCTION: After coronary stenting, the incidence of subacute stent thrombosis have been reduced to 0% using aspirin and ticlopidine, in studies with selected populations and intracoronary ultrasounds. OBJECTIVE: To evaluate the incidence and predictors of subacute stent thrombosis in a nonselected population, using antithrombotic therapy. METHODS: We studied 285 stents, consecutively and successfully implanted in 268 lesions of 226 patients. We used high pressure balloon inflation without intracoronary ultrasound. Post-stenting protocol included aspirin and ticlopidine during four weeks with no anticoagulation. We defined subacute stent thrombosis as death, acute myocardial infarction myocardial infarction or angiographic occlusion of stent, with TIMI flow 0-1, after the first 24 hours and during the first month. RESULTS: Four patients presented events (1.7%): Three nonfatal myocardial infarction after discharge, with documented angiographic thrombosis of stent, and one death due to in-hospital myocardial infarction. All three non-fatal AMI, occurred in vessels less than 3 mm (p = 0.07) and in patients taking aspirin without ticlopidine (p < 0.001). After discharge, three (17%) of 18 patients with inadvertent discontinuation of ticlopidine presented subacute stent thrombosis, in contrast to none of 25 patients taking ticlopidine without aspirin. Excluded patients with discontinuation of ticlopidine, the incidence of subacute stent thrombosis was 0.5%. CONCLUSION: After intracoronary stenting in a nonselected population, using antithrombotic treatment with aspirin and ticlopidine, we may expect a rate of subacute stent thrombosis about 1%. Ticlopidine seems to have the main role in preventing subacute stent thrombosis, above all in predisposing circumstances as small vessels. 相似文献
996.
Pascual Figal DA Valdés Chávarri M López Candel J Vicente T Pérez Lorente F García Alberola A Ruipérez JA 《Revista espa?ola de cardiología》2000,53(8):1040-1046
OBJECTIVE: To assess the clinical outcome of coronary stenting in small vessels (< 3 mm), using high pressure balloon inflation and antithrombotic therapy. PATIENTS AND METHODS: Vessel size was evaluated as < or >= 3 mm at the time of procedure and measured at a level of maximum diameter. We studied 234 consecutive patients with placement of 300 stents in 279 lesions, comprising 84 stents implanted in 79 lesions located at small vessels (< 3 mm). The standard technique included high pressure balloon inflation (15.8 +/- 2.2 atm) and post-stenting therapy with ticlopidine and aspirin for one month. Mean clinical follow-up was 17.6 +/- 10 months. RESULTS: Procedural success without in-hospital major events was similar between small and large vessels (93.7 in vessels of < 3 mm vs 93.5% in vessels of >= 3 mm; p = NS). Three small vessels presented subacute stent thrombosis, whereas no thrombotic occlusion occurred in large vessels (3.8 vs 0%; p = 0.006). At two years, small vessels had a lower target lesion revascularization free survival (73.6 vs 90.3%; p < 0.001). After adjustment for variables previously described as predictors of stent restenosis, in multivariate analysis, a small vessel of < 3 mm was an independent predictor of target lesion revascularization (p = 0.001). Although patients with stenting in small vessels did not differ significantly in terms of any cause death (4.6 vs 3.8%; p = 0.7) nor acute myocardial infarction (2.9 vs 1.1%; p = 0.3), event-free survival was significantly lower after two years (69.1 vs 86.6%; p < 0.001). CONCLUSIONS: As compared to large vessels, coronary stenting in small vessels was performed with similar rates of initial success, however they had a significantly worse clinical long-term outcome in terms of subacute stent thrombosis and target lesion revascularization at follow-up. 相似文献
997.
T. Brzozowski P. Ch. Konturek S. J. Konturek Z. Sliwowski D. Drozdowicz S. Kwiecie R. Pajdo A. Ptak M. Pawlik E. Hahn 《Digestive and liver disease》2000,32(7):583-594
BACKGROUND & AIM: New class of nitric oxide-releasing non-steroidal anti-inflammatory drugs was shown to inhibit cyclooxygenase and prostaglandin generation without causing mucosal damage but whether these agents are capable of affecting gastric mucosal damage induced by strong irritants and healing of chronic gastric ulcers remains to be studied. In this investigation, effects of nitric oxide-releasing aspirin and nitric oxide-releasing naproxen were compared with those of native agents on gastric lesions provoked by 100% ethanol and on healing of chronic acetic acid ulcers. RESULTS: Both, nitric oxide-releasing aspirin and naproxen dose-dependently attenuated ethanol-induced damage and produced a significant rise in gastric blood flow but did not delay healing of gastric ulcers while native aspirin and naproxen had no influence on ethanol-induced gastric damage but significantly prolonged ulcer healing, reduced gastric blood flow and suppressed mucosal generation of prostaglandin E2. The gastroprotective and hyperaemic effects of both nitric oxide-non-steroidal anti-inflammatory drugs were completely abolished by ODQ, an inhibitor of guanylyl cyclase-cGMP system but not influenced by suppression of nitric oxide-synthase with L-NNA. The damaging effects of native acetyl salicylate acid or naproxen were aggravated by acidification of these non-steroidal anti-inflammatory drugs but the exogenous acid added to nitric oxide-acetyl salicylate acid or nitric oxide-naproxen failed to influence their effect. Despite inhibiting of PGE2 generation, both nitric oxide-releasing derivatives and native aspirin and naproxen failed to affect expression of cyclooxygenase-1 mRNA but upregulated the cyclooxygenase-2 mRNA. Concurrent inhibition of cyclooxygenase-2 by selective inhibitor NS-398 which by itself delayed ulcer healing and attenuated the gastric blood flow at ulcer margin, significantly worsened the effects of these nitric oxide-non-steroidal anti-inflammatory drugs and their parent drugs on ulcer healing and the gastric blood flow at the ulcer margin. CONCLUSIONS: 1) Coupling of nitric oxide to aspirin or naproxen attenuates ethanol-induced damage, possibly due to an increase in gastric microcirculation mediated by excessive release and action of nitric oxide that probably compensates for PG deficiency induced by non-steroidal anti-inflammatory drugs; and 2) nitric oxide-non-steroidal anti-inflammatory drug, unlike classic non-steroidal anti-inflammatory drugs, does not affect intact gastric mucosa and fails to delay the healing of pre-existing ulcers. 相似文献
998.
Prevalence of the G20210A prothrombin gene mutation in Northwestern Greece and association with venous thromboembolism. 总被引:1,自引:0,他引:1
Ch G Zalavras S Giotopoulou E Dokou M Mitsis H V Ioannou C Tsaousi A Tzolou N Kolaitis G Vartholomatos 《International angiology》2003,22(1):55-57
AIM: The G20210A mutation of the prothrombin gene is a genetic risk factor for venous thromboembolism (VTE). Variability exists in the mutation prevalence in both normal individuals and VTE patients. The aim of this study was to determine the mutation prevalence in Northwestern Greece and evaluate its association with VTE. METHODS: Presence of the G20210A mutation was investigated using DNA analysis in 176 consecutive patients with a history of venous thrombosis or pulmonary embolism and in 300 healthy controls, all Caucasian residents of Northwestern Greece. RESULTS: The mutation was present 12 patients (6.8%) and 8 controls (2.7%). The odds ratio for presence of the mutation versus the normal genotype in VTE was 2.7 (95% CI: 1.1 to 6.7), which was statistically significant. The prevalence of the G20210A prothrombin gene mutation in Northwestern Greece is 2.7% (95% CI: 0.8% to 4.4%) with an allele frequency of 1.3% (95% CI: 0.4% to 2.3%). CONCLUSION: The G20210A mutation of the prothrombin gene is associated with VTE in the Caucasian residents of this geographic region. 相似文献
999.
Zervou EK Boumba DS Liaskos C Georgiadou S Tsianos EV Dalekos GN 《European Journal of Internal Medicine》2003,14(1):39-44
Background: The risk of infection with transfusion-transmitted viruses has been reduced remarkably. A zero-risk blood supply, however, remains a popular goal. A 3-year prospective donor study was conducted in the Epirus region of Greece to determine the prevalence of human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis B virus, and hepatitis C virus (HCV). Herein, we report the prevalence of HIV, HTLV, and HCV infection markers in this area. Methodology: Between January 1, 1995 and December 31, 1997, 6696 donors were investigated for the presence of anti-HIV, anti-HTLV, and anti-HCV antibodies using standard enzyme immunoassays (EIA). Every sample with anti-HCV reactivity by third-generation EIA was further investigated using a third-generation recombinant immunoblot assay (RIBA 3.0) and HCV-RNA by a combination of polymerase chain reaction (PCR) and DNA EIA. Results: None of the donors tested positive for anti-HIV or anti-HTLV antibodies. In contrast, anti-HCV was detected in 41 donors (0.61%). Using a RIBA 3.0 test, eight donors tested positive and eight had indeterminate results, while 25 tested negative. Seven of the eight donors with both EIA and RIBA 3.0 reactivity had increased levels of aminotransferases and detectable serum HCV-RNA. The remaining 34 donors had repeatedly normal aminotransferases and three times negative HCV-RNA. Liver biopsy was performed in anti-HCV/HCV-RNA-positive donors (7/41). The lesions were compatible with chronic hepatitis C in all of them. Conclusion: A zero prevalence of HIV and HTLV infection markers was found. Although the number of annual donations in this study was relatively low, the negative data for HIV and HTLV clearly indicate that rates of these infections are low in our region and that infected donors will be seen infrequently. HCV infection in blood donors remains very low in our region and is similar to the data reported in other industrialized countries. In fact, the prevalence of definite HCV infection seems to be very low (7/6696; 0.1%). However, a significant proportion of anti-HCV-reactive donors by third-generation EIA (33/41) had indeterminate or negative results by the RIBA 3.0. The latter donors were repeatedly negative for HCV-RNA. This finding may indicate that some donors tested false-positive for anti-HCV, although the possibility of true HCV infection contracted in the distant past cannot be excluded. In our opinion, close attention to mandatory principles of transfusion medicine, along with the screening of plasma donors using nucleic acid amplification technology, are the only methods that can further ensure the safety of our blood supply. 相似文献
1000.