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E Sanabria

Publications and source records attributed to E Sanabria.

16 recordsLinked to original sources
PubMed2001

Role of endothelin and isoprostanes in slow pressor responses to angiotensin II.

We tested the hypothesis that angiotensin II (Ang II)-induced stimulations of endothelin (ET) and isoprostanes are implicated in the slow pressor responses to Ang II. We infused either vehicle (group 1) or Ang II (groups 2 to 4) intravenously at 5 ng/kg per minute via osmotic pumps for 15 days into Sprague-Dawley rats. Groups 3 and 4 received 30 mg/kg per day of either losartan (Ang II type 1 receptor blocker) or bosentan (ET(A) and ET(B) receptor blocker) in their drinking water. We measured systolic blood pressure (SBP) every 3 days during the infusion. Plasma levels of Ang II, ET, isoprostanes, and urinary nitrites were determined at 15 days. Vehicle infusion did not change SBP (from 138+/-13 to 136+/-2 mm Hg at day 15). Circulating Ang II, ET, and isoprostane levels were 35+/-9, 39+/-3, and 111+/-10 pg/mL, respectively, whereas urinary nitrites were 2.3+/-0.4 microgram/d. Ang II increased SBP (from 133+/-10 to 158+/-8 mm Hg), plasma Ang II (179+/-77 pg/mL), and isoprostanes (156+/-19 pg/mL) without altering ET levels (38+/-5 pg/mL) or urinary nitrites (1.8+/-0.5 microgram/d). Losartan prevented Ang II-induced increases in SBP and isoprostanes (SBP went from 137+/-5 to 120+/-4 mm Hg; isoprostanes were 115+/-15 pg/mL) while increasing urinary nitrite levels (5.2+/-1.1 microgram/d). Losartan did not alter Ang II (141+/-57 pg/mL) or ET (40+/-4 pg/mL) levels. Bosentan also blocked Ang II-induced hypertension (from 135+/-4 to 139+/-3 mm Hg) but did not decrease isoprostanes (146+/-14 pg/mL). Ang II (63+/-11 pg/mL), ET levels (46+/-2 pg/mL), and urinary nitrites (2.8+/-0.4 microgram/d) were not altered. In conclusion, our results suggest that low-dose Ang II increases isoprostanes via its Ang II type 1 receptor and causes an ET-dependent hypertension, without altering circulating ET levels.

Angiotensin II↗
PubMed1998

The safety and efficacy of Australian tick-borne disease vaccine strains in cattle in Paraguay.

Glycerol preserved, frozen tick-borne disease vaccine strains developed in Australia were imported into Paraguay to test their safety in pregnant Holando heifers and their efficacy against challenge from inoculated local field strains of Babesia bigemina, B. bovis and Anaplasma marginale in Hereford X Criolla heifers. The two Babesia strains proved to be safe and the B. bovis K strain was very effective in providing immunity to a local field strain of B. bovis. The B. bigemina efficacy trial was inconclusive, possibly due to the avirulent nature of the local field strain used in challenge. The A. centrale strain did not prove to be as safe as would be desirable in safety trials, neither did it provide as good protection as the Babesia strains in the efficacy trial. It was concluded that the Babesia strains provided good protection against field challenge in Paraguay and were safe to use in highly susceptible cattle, however an alternative to A. centrale should be sought to provide protection against local strains of A. marginale.

Anaplasma↗
PubMed1981

[Scintigraphy with technetium dimercaptosuccinic acid (99 m TC DMSA). Contribution to the functional assessment of individual kidneys (author's transl)].

Renal uptake of 99m Tc DMSA was used to evaluate the renal function of 16 healthy subjects (controls) and 115 patients with various urinary tract diseases. Scintigraphic examination was carried out 6 hours after an intravenous injection of the product. In the 16 controls Tc DMSA uptake was 25.7 +/- 2.48% in the right kidney and 24.4 +/- 2.86% in the left kidney. In 36 patients with one single hypertrophied kidney, there was a correlation (r = 0.850) between creatinine clearance and Tc DMSA uptake, which was higher than in normal subjects (39.23 +/- 9.9%). In the group of 68 patients with unilateral (31) or bilateral (37) renal disease, a significant correlation (r = 0,725) was observed between kidney-to-kidney ratios of urea clearance and Tc DMSA uptake, so that renal impairment could be quantified. Quantitative scintigraphy did not appear to be of assistance in the remaining 11 patients with obstructive uropathy, as it overestimated renal function. The results obtained with 99 m Tc DMSA scintigraphy should be helpful in choosing between nephrectomy and conservative surgery and in assessing the degree of compensatory hypertrophy in single kidneys.

Creatinine↗
PubMedDate not supplied

[Affective disorders and dementia of the frontal lobe type. Hypothesis of a pathogenic relationship].

The evolution of some dysthymic states towards dementia is now rarely considered whereas it was well known at the beginning of the century. In French the final stage of this evolution was known as "démence vésanique". In recent years it has been noted that a proportion of patients with presenile dementia do not have Alzheimer's disease (AD) but a particular type of cognitive impairment., called dementia of the frontal lobe type (DFT), characterised by clinical and neuropsychological signs of frontal lobe disorder as well as an anterior defect of cerebral perfusion or metabolism. The onset of DFT is insiduous and marked by personality changes and inappropriate affect. It has not yet been reported as starting with true dysthymic disorders. PATIENTS AND METHODS. Ten right handed patients (F/M = 9/1) became dysthymic in their fifties (m = 49.8 + 7.6 yr). All initially met the DSM III-R criteria for mood disorders. They were all treated with the standard drugs or ECT. Although initially responsive all the patients relapsed and their dysthymic disorders became less typical in presentation. At a mean age of 63.6 +/- 2.9 yrs a particular type of dementia became evident. None of the patients had a previous history of mood disorder or a family history of dementia. The demented patients received thorough clinical examinations and 8/10 were tested with the Wechsler Adult Intelligence Scale (WAIS). All had XCT and HMPAO-SPECT scans using a rotating gamma camera. Three patients had a MRI Scan. RESULTS. The main symptoms were apathy and a lack of spontaneity as a result of which the patients were no longer able to live alone. HMPAO-SPECT: All the patients had clear hypoperfusion of the frontal and temporal lobes with seven showing a left predominance. XCT: A moderate degree of cortical atrophy, more pronounced in the frontal lobes, was observed in 6 patients. In 3 of them a previous XCT scan had been normal. MRI: Subcortical white matter hyperintensities were seen in the 3 patients examined. DISCUSSION. Although our patients do not probably form, with regard to a etiology a homogeneous group, they share common characteristics which are very similar to those which differentiates DFT from AD. We postulate that some dysthymic disorders of the presenium might represent the initial stage of this type of dementia. This hypothesis relies on the evidence for frontal dysregulation in mood disorders as demonstrated, for example, by PET studies. In these cases the cortical abnormalities usually disappear as the dysthymia improves and are considered functional phenomena. They may correspond to the mechanism of deafferentation (or diaschisis). This implies a primary lesion, presumably located at a subcortical level (for instance a white matter lesion) producing a disruption of function in a distant (initially) intact brain region. As a supplementary hypothesis we propose that with time, and for as yet unknown reasons, the frontal hypoperfusion in our patients lost its reversibility and that, as a result, a particular type of dementia became manifest. In some cases this diaschisis protractiva may lead to secondary cortical atrophy. CONCLUSIONS. A DFT was found in 10 patients who had become dysthymic in their fifties. A pathogenic hypothesis i.e. diaschisis protractiva, is proposed, based on the evidence of neuroimaging studies.

Aged↗