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61.
Rodriquez A Martin A Oterino JA Blanco I Jimenez M Perez A Novoa JM 《Digestive diseases (Basel, Switzerland)》1999,17(4):235-240
AIMS: In order to assess the possible participation of nitric oxide (NO) in renal function during compensated hepatic cirrhosis, we studied renal function, the plasma and urinary levels of cGMP and the concentration of nitrates and nitrites, as markers of NO synthesis in blood and urine, in 10 patients with Child A hepatic cirrhosis as compared with 10 control subjects, both under basal conditions and during stimulation (amino acid-induced glomerular hyperfiltration). METHODS: To study renal function, the glomerular filtration rate (GFR), effective renal plasma flow (ERPF), renal functional reserve (RFR), renal venous resistance (RVR) and the filtration fraction (FF) were measured. Renin and aldosterone levels were determined to assess the possible involvement of these compounds in the renin-angiotensin-aldosterone axis. RESULTS: GFR and ERPF were significantly lower in the patients with cirrhosis than in the controls (mean GFR: 82+/-12.3 vs. 105+/-15 ml/min, p = 0. 01; ERPF 452+/-86 vs. 543+/-56 ml/min, p = 0.002). The RFR value was similar in both groups. In the basal situation cGMP levels were higher in plasma and urine in patients with cirrhosis than in the controls (plasma cGMP in cirrhosis 8.4+/-2.4 vs. 4.2+/-3.5 pmol/ml; urine cGMP in cirrhosis 1.2+/-2.1 vs. 0.68+/-0.1 pmol/ml). The NO levels were also higher in plasma and urine in patients with cirrhosis vs. controls (plasma NO in cirrhosis 45.5+/-9.2 vs. 30. 3+/-1.2 micromol/l; urinary NO in cirrhosis 6.2+/-1.3 vs. 3.1+/-2.3 micromol/ml). In both groups the amino acid perfusion increased GFR, ERPF, cGMP and NO levels in plasma and urine. In the patients with cirrhosis the RVR decreased significantly during perfusion and no noteworthy changes in FF were observed. The GFR values observed during amino acid perfusion were similar in patients with cirrhosis and portal hypertension to those observed in the controls (27.2+/-12 vs. 25.3+/-16%). However, the changes induced the ERPF were more marked in patients with cirrhosis (cirrhosis 35.3+/-15 vs. 22. 2+/-13%, p = 0.02). CONCLUSIONS: The present findings point to certain alterations in renal function in patients with hepatic cirrhosis and portal hypertension without ascitis, a clear difference being visible between the ERPF and GFR following amino acid-induced stimulation. The significant elevation in cGMP and NO levels in plasma and urine implies a maintained vasodilatory action that may at least partly compensate the vasoconstrictor effects of angiotensin II. 相似文献
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The short-term effects of high-dose testosterone on sleep,breathing, and function in older men 总被引:12,自引:0,他引:12
Liu PY Yee B Wishart SM Jimenez M Jung DG Grunstein RR Handelsman DJ 《The Journal of clinical endocrinology and metabolism》2003,88(8):3605-3613
Androgen therapy may precipitate obstructive sleep apnea in men. Despite increasing androgen use in older men, few studies have examined sleep and breathing. Randomized, double-blind, placebo-controlled studies examining effects of testosterone simultaneously on sleep, breathing, and function in older men are not available. Seventeen community-dwelling healthy men over the age of 60 yr were randomized to receive three injections of im testosterone esters at weekly intervals (500 mg, 250 mg, and 250 mg) or matching oil-based placebo and then crossed over to the other treatment after 8 wk of washout. Polysomnography, anthropometry, and physical, mental, and metabolic function were assessed at baseline and after each treatment period. Testosterone treatment reduced total time slept ( approximately 1 h), increased the duration of hypoxemia ( approximately 5 min/night), and disrupted breathing during sleep (total and non-rapid eye movement respiratory disturbance indices both increased by approximately seven events per hour) (all P < 0.05). Despite expected effects on body composition (increase in total and lean mass, reduction in fat mass, P < 0.05, bioimpedance method), upper airway dimensions did not change (acoustic reflectometry). Driving ability (computer simulation), physical activity (accelerometry, Physical Activity Scale in the Elderly), quality of life (SF36, Functional Outcomes of Sleep Questionnaire), mood (Profile of Mood States Questionnaire), sleepiness (Epworth, Stanford scales), and insulin resistance (homeostasis model) also were not changed by treatment. Short-term administration of high-dose testosterone shortens sleep and worsens sleep apnea in older men but did not alter physical, mental, or metabolic function. These changes did not appear to be due to upper airway narrowing. Further study of longer-term lower-dose androgen therapy on sleep and breathing is needed to evaluate its safety in older men. 相似文献
64.
C Dupuis H Ducoulombier G Rey A Choussat M Jimenez 《Archives des maladies du coeur et des vaisseaux》1987,80(4):500-511
Twenty-four cases of anomalous origin of the left coronary artery from the pulmonary artery are reported. These cases were collected over 27 years divided into three 9-year periods according to the years of the initial studies. The clinical aspects and diagnostic investigations (notably echocardiography, myocardial radioisotope imaging and various angiographic procedures) are reviewed; aortography seems to be, even now, the best exploratory method. Treatment is analyzed according to the periods of observations. From the earliest cases it may be concluded that ligation proved ineffective in infants and medical treatment often failed. Progressively, medical treatment with digitalis (now better controlled), potassium-sparing diuretics and vasodilators has become more effective. On the other hand, direct reimplantation of the left coronary artery onto the aorta has become the preferred surgical procedure. Among the 8 most recent cases (seen between 1977 and 1986), 4 were cured by medical treatment under the age of 3 and subsequent reimplantation. In the other 4 patients asystolia responded to medical treatment, and these children are now awaiting reimplantation. 相似文献
65.
BACKGROUND AND AIM OF THE STUDY: Perturbations of leaflet geometry are the final end point through which left ventricular (LV) ischemia causes incomplete mitral leaflet closure and resultant mitral regurgitation (MR). Geometric inconsistencies observed with valvular or subvalvular structural alterations raise several questions. METHODS: A new in-vitro LV flexible bag model was developed in order to visualize and analyze leaflet geometric changes under simulated pathological ischemic MR conditions. RESULTS: Papillary muscle (PM) displacement and annular dilatation decreased leaflet coaptation length, leading to significant MR. Symmetrical PM displacement shifted the coaptation line towards the leaflet edges and created central gaps along this line. Asymmetric PM displacement generated diametrically uneven coaptation with a tent-shaped leaflet at the tethered PM side, while the leaflet bulged at the opposite side towards the left atrium. CONCLUSION: Leaflet geometry during systole is affected by subvalvular structures. Asymmetric PM displacement, which may occur in regional or acute myocardial infarction, induces irregular deformation of the leaflet's coaptation line and, as a result, MR at the tethered side. Direct visualization of leaflet perturbation under these simulated pathological conditions may promote understanding of mechanisms present in ischemic MR. 相似文献
66.
67.
Guering Eid-Lidt Agustín Rivera Rodríguez Joaquín Jimenez Castellanos Julio I. Farjat Pasos Kathia E. Estrada López Jorge Gaspar 《JACC: Cardiovascular Interventions》2021,14(4):378-385
ObjectivesThe aim of this study was to compare the rate of proximal radial artery occlusion (RAO) with Doppler ultrasound between distal and conventional radial access 24 h and 30 days after a transradial coronary procedure.BackgroundThe use of distal radial access to prevent proximal RAO (PRAO) in the proximal segment at 24 h and 30 days after a procedure, compared with conventional radial access, is unknown.MethodsThis was a prospective, comparative, longitudinal, randomized study. A total of 282 patients were randomized to either proximal radial access (n = 142) or distal radial access (n = 140) to evaluate the superiority of the distal approach in the prevention of PRAO with Doppler ultrasound 24 h and 30 days after a transradial coronary procedure.ResultsIn the per protocol analysis, the rates of PRAO at 24 h and 30 days were 8.4% and 5.6% in the proximal group and 0.7% and 0.7% in the distal group, respectively (24 h: odds ratio [OR]: 12.8; 95% confidence interval [CI]: 1.6 to 100.0; p = 0.002; 30 days: OR: 8.2; 95% CI: 1.0 to 67.2; p = 0.019). In an intention-to-treat analysis, the 24-h and 30-day rates of PRAO were 8.8% and 6.4% for proximal radial access and 1.2% and 0.6% in the distal radial access group (24 h: OR: 7.4; 95% CI: 1.6 to 34.3; p = 0.003; 30 days: OR: 10.6; 95% CI: 1.3 to 86.4; p = 0.007).ConclusionsDistal radial access prevents RAO in the proximal segment at 24 h and 30 days after the procedure compared with conventional radial access. 相似文献
68.
Elevation of endothelial microparticles, platelets, and leukocyte activation in patients with venous thromboembolism 总被引:5,自引:0,他引:5
Chirinos JA Heresi GA Velasquez H Jy W Jimenez JJ Ahn E Horstman LL Soriano AO Zambrano JP Ahn YS 《Journal of the American College of Cardiology》2005,45(9):1467-1471
OBJECTIVES: The purpose of this research was to determine the levels of platelet, leukocyte, and endothelial activation and markers of cellular interactions in patients with venous thromboembolism (VTE). BACKGROUND: The details of interactions between endothelium, platelets, and leukocytes in VTE are not well understood. METHODS: We studied 25 patients with VTE and compared 25 healthy controls. We used flow cytometry to measure: 1) endothelial microparticles (EMP) identified by CD31+/CD42b- (EMP(31)) or E-selectin (EMP(62E)); 2) platelet microparticles (CD31+/CD42b+); 3) surface expression of P-selectin in platelets and CD11b in leukocytes; 4) EMP-monocyte conjugates (percentage of monocytes positive for E-selectin); and 5) platelet-leukocyte conjugates (PLC) expressed as percentage of leukocytes positive for CD41. RESULTS: Patients with VTE had marked elevations of EMP(31) (2,193 vs. 383 counts/microl; p = 0.003), EMP(62E) (368 vs. 223 counts/microl; p = 0.001), and EMP-monocyte conjugates (3.3% vs. 2.5%; p = 0.002), as well as increased activation of platelets (35.2 vs. 5.0 fluorescence intensity units for P-selectin; p < 0.0001) and leukocytes (13.9 vs. 7.7 U for CD11b; p = 0.004). Also elevated in VTE were PLC (61.7% vs. 39.6%; p = 0.01). Expression of CD11b in leukocytes strongly correlated with PLC (r = 0.74; p < 0.0001). CONCLUSIONS: Marked activation of endothelium, platelets, and leukocytes occurs in VTE, and VTE, or the accompanying inflammatory process, involves the release of EMP and formation of EMP-monocyte conjugates and PLC. These findings support prior studies suggesting that release of EMP and their binding to monocytes are key events in thrombogenesis. Our findings also support the concept that the formation of PLC regulates leukocyte activation and participates in linking thrombosis with inflammation. 相似文献
69.
J. F. San Miguel M. Gonzáalez A. Gascón Ma J. Moro J. M. Hernáandez F. Ortega R. Jimenez L. Guerras M. Romero F. Casanova M. A. Sanz J. Sáanchez J. A. Portero A. Orfao 《British journal of haematology》1991,77(2):185-190
In 112 untreated myeloma patients we have analysed the immunophenotype of plasma cells both by immunofluorescence (IF) and immunocytochemistry (APAAP). Both techniques yielded similar results pointing to an important degree of heterogeneity in antigenic expression not only between different patients but also within the same patient. The expression of CD38 and Han-PC1 antigens (Ags) was almost constant (greater than 90% positive cases), while CD9 was detected in 66% of the cases. On the other hand, less than one third of patients were positive for CD10, CD20 and HLA-DR and generally with a weak expression (less than 30% positive plasma cells). In occasional cases plasma cells were weakly positive for the myelomonocytic markers CD13 (9%), CD15 (25%) and CD14 (6%). The possibility that this heterogeneity might be the result of different stages of differentiation of the neoplastic clone is suggested both by the positive correlation in the expression of some of these antigens (CD10, CD9, CD20, HLA-DR) and by the relationship between CD10 and myeloid antigens with immature plasma cell morphology. Finally, the cALLA antigen does not seem to be of significant value in predicting survival. Moreover, none of the other markers explored showed a clear influence in the course of the disease, although the tendency towards a lower survival found for the CD20+ cases as well as the association of the expression of some antigens and advanced clinical stage, may warrant further studies in a larger series of patients. 相似文献
70.