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141.
Daniela Delwing Dbora Delwing Fbria Chiarani Andra G. Kurek Angela T.S. Wyse 《International journal of developmental neuroscience》2007,25(1):17-22
In the present study, we initially investigated the in vivo (acute and chronic) and in vitro effects of proline on cytochrome c oxidase (complex IV) activity in rat cerebral cortex to test the hypothesis that proline might alter energy metabolism and that this alteration could be provoked by oxidative stress. The action of alpha-tocopherol and ascorbic acid on the effects produced by proline was also evaluated. For acute administration, 29- and 60-day-old rats received one subcutaneous injection of proline (18.2 micromol/g body weight) or an equivalent volume of 0.9% saline solution (control) and were sacrificed 1h later. For chronic treatment, proline was injected subcutaneously twice a day at 10h intervals from the 6(th) to the 28(th) day of age. Rats were sacrificed 12h (29(th)) or 31 days (60(th)) after the last injection. Results showed that acute administration of proline significantly diminished the activity of cytochrome c oxidase in the cerebral cortex of 29- and 60-day-old rats. On the other hand, chronic hyperprolinemia reduced this complex activity only on day 29, but not on the 60(th) day of life. In another set of experiments, 22-day-old rats or 53-day-old rats were pretreated for 1 week with daily intraperitoneal administration of alpha-tocopherol (40 mg/kg) and ascorbic acid (100mg/kg) or saline. Twelve hours after the last antioxidant injection, rats received a single injection of proline or saline and were killed 1h later. In parallel to chronic treatment, rats received a daily intraperitoneal injection of alpha-tocopherol and ascorbic acid from the 6(th) to the 28(th) day of life and were killed 12h after the last injection. Results showed that the pretreatment with alpha-tocopherol and ascorbic acid before acute proline administration or concomitant to chronic proline administration significantly prevented these effects. We also observed that proline (3.0 microM-1.0 mM) when added to the incubation medium (in vitro studies) did not alter cytochrome c oxidase activity. Data suggest that the inhibitory effect of proline on cytochrome c oxidase activity is possibly associated with oxidative stress and that this parameter may be involved in the brain dysfunction observed in hyperprolinemia. 相似文献
142.
María de Oña Navarro Santiago Melón Susana Méndez Beatriz Iglesias Ana Palacio María J. Bernardo José L. Rodriguez-Lambert Ernesto Gómez 《Transplant international》2002,15(11):570-573
Ganciclovir (GCV) prophylaxis or pre-emptive therapy significantly reduce the rate of cytomegalovirus (CMV) disease and viremia, but increase the potential for emergence of ganciclovir-resistant CMV strains. The inhibitor concentration at 50% (IC(50)) of GCV from 156 CMV isolates from 59 renal or heart transplant recipients was calculated by means of a rapid phenotypic susceptibility assay. Twenty-seven strains were from 14 patients undergoing GCV therapy. The IC(50) was higher in patients under the prophylaxis regimen. One CMV strain, from a heart transplant recipient, became GCV-resistant after 1 month of therapy (IC(50)=13.7 micromol/l). These data, together with clinical and virological markers, suggested that a switch to foscarnet was necessary, and good evolution was observed. Thus, assay of CMV susceptibility to GCV could be helpful in clinical management. 相似文献
143.
Humberto Morais Luísa Moura Branco Rosa Cunha Telmo Martins 《Revista portuguesa de cardiologia》2007,26(4):367-372
Submitral ventricular aneurysm is a thoroughly studied pathology but is not well known due to its rarity. Clinically, it is manifested by symptoms and signs of heart failure, mitral regurgitation and/or ventricular arrhythmias, and may be associated with thromboembolic phenomena and myocardial ischemia due to compression of the coronary arteries by the aneurysm. A rare complication of this type of aneurysm is rupture into the left atrium. Transthoracic echocardiography plays an important role in the definitive diagnosis of this pathology, although the role of transesophageal echocardiography in the evaluation of these patients is less known. We report a case of a submitral ventricular aneurysm complicated by rupture into the left atrium, which was diagnosed by transesophageal echocardiography. 相似文献
144.
J A San Román I Vilacosta J Zamorano C Almería F J Cortés E Iturralde L Sánchez Harguindey 《Revista espa?ola de cardiología》1992,45(3):219-221
Three cases with suspected pulmonary artery embolism are presented, in which transesophageal echocardiography showed a mass in the right pulmonary artery consistent with thrombus. The relevant diagnostic contributions of transesophageal echocardiography are discussed. 相似文献
145.
146.
J M Barbero A I Ezpeleta M López Gil J L Barroso F García-Cosío 《Revista espa?ola de cardiología》1991,44(7):485-487
A 76-year-old woman with an inferior wall myocardial infarction, with right ventricular involvement, developed severe arterial hypoxemia with neurological involvement. Pulmonary edema or embolism and chronic obstructive pulmonary disease were ruled-out, and a right-to-left shunt was demonstrated by contrast echocardiography at the level of the foramen ovale. After inotropic support and oxygen supplementation, the patient recovered, although with significant neurological sequelae. No focal lesions were detected in the central nervous system by computerized tomography. Hypoxemia improved, coinciding with the disappearance of right-to-left shunt by contrast echocardiography. 相似文献
147.
Captopril is a suitable drug to treat high blood pressure in diabetic patients. This Angiotensin-Converting Enzyme Inhibitor (ACEI) is a vasodilator without tachycardia and saline retention. Furthermore, captopril is one of antihypertensive drugs with less adverse effects. It does not induce metabolic changes, improves glucose tolerance and brake the evolution of renal insufficiency. About 50-60% of patients are under control (DBP < 90 mmHg) with captopril monotherapy. In the present paper, were included 64 women and 16 men with diabetes mellitus and mild-moderate hypertension, I-II phase WHO. The average age (mean +/- S.D.) was 66.6 +/- 9.2 years. All patients were treated with 25 mg/12 h of captopril, for one month. If blood pressure was not under control, captopril treatment enhanced to 50 mg/12 h during second month. After this period of two months, patients under control were got out of this study. 37 patients (46.25%) needed a second drug. In randomized form, 20 patients associated 25 mg HCTZ one time a day (CAP + HCTZ); and 17 patients associated 20 mg/12 h of nifedipine retard (CAP + NIF). The study continued for 4 months more. Both treatments reduced blood pressure in significant form without changes statistical significant in the heart rate, weight, glycemia, cholesterol, triglycerides, c-HDL, uric acid, creatinine, Na+ and K+ blood levels. CAP + HCTZ controlled (DBP < 90 mHg) 85% and CAP + NIF 81.25% of patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
148.
149.
Summary In this study, the largest Nordic study of its kind, investigated psychosexual dysfunction among subjects aged 55–57 years. The cohort included 862 subjects of both sexes and all were interviewed using the Diagnostic Interview Schedule (DIS). Results showed that 122 subjects had a lifetime diagnosis of psychosexual dysfunction. The lifetime prevalence of psychosexual dysfunction was 14.4%; of inhibited sexual desire, 9.8%; of inhibited sexual excitement, 3.5%; of inhibited orgasm, 2.1%; and of functional dyspareunia, 1.3%. Of the subjects with psychosexual dysfunction, 73% were women. The frequency was highest in those who had never married. Separated subjects had rates intermediate between the married and the never-married. The majority (76%) of affected subjects had only one dysfunction. However, 57% of them had received another psychiatric diagnosis at some time. Subjects with psychosexual dysfunction wereless frequently diagnosed as suffering from alcohol abuse and dependence and social phobia than subjects with no psychosexual dysfunction. 相似文献
150.
Reports of the human teratogenicity of retinoids have raised concern about the potential human teratogenicity of high doses of vitamin A. Nevertheless, there are few human case reports of excess intake of vitamin A during pregnancy and defective outcomes. No epidemiological studies have been carried out on this subject. Here we present the results of an epidemiological study of prenatal exposure to high doses of vitamin A in Spain, using data from the Spanish hospital-based, case-control registry. Although it is difficult to reach conclusions with such a very low exposure level (1.3 per 1,000 livebirths), our results suggest that a teratogenic effect might exist for exposures to high doses of vitamin A (OR = 0.5, p = 0.15 for less than 40,000 FU and OR = 2.7, p = 0.06 for 40,000 1U or more). As we might expect, this effect also seems to be related to the organogenetic status (OR = 5.4, p = 0.1 for 1st –2nd month, OR = 1.8, p = 0.4 for 3rd onwards) at the time of exposure. 相似文献