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C Suarez

Publications and source records attributed to C Suarez.

At least 37 records · Page 2Linked to original sources

How should we treat hypertensive women with cardiac and renal impairment?

Arterial hypertension is the most common chronic medical condition requiring office visits to physicians and is a major contributing factor to the development of myocardial infarction and stroke. Its importance as a cardiovascular risk factor is at least as significant in women as in men; however, the ever-growing literature on hypertension shows surprisingly little data concerning sex differences. Large clinical trials of antihypertensive treatment have not clearly demonstrated gender differences in blood pressure response and outcome, but the majority of patients in these trials were men. Even so, some evidence indicates that white women treated for hypertension obtain less benefit than men. The pathophysiology of hypertension in men and women is similar in many aspects, but important gender differences are now emerging. Studies designed to clarify these differences are required, as a better knowledge of the underlying mechanisms will allow for a more precise stratification of risk and a more accurate approach to both nonpharmacologic and pharmacologic treatment.

Adrenergic beta-Antagonists↗

Antifungal activity of plant extracts against Candida albicans.

In previous papers, we reported the antimicrobial activity of plants used in Argentine folk medicine against different micro-organisms. The present study deals with the screening of 11 of these plants against the opportunistic pathogen fungus Candida albicans. Aqueous extracts 6% p/v (6 mg dry plant per 100 ml of water) were checked against fungus cultures by the agar-well diffusion method. Five extracts showed antifungal activity.

Candida albicans↗

Expression of carbonic anhydrase IV in carbonic anhydrase II-deficient mice.

Chronic metabolic acidosis (CMA) in the rabbit upregulates carbonic anhydrase (CA) IV in the proximal convoluted tubule (PCT). This study was designed to assess CA IV expression in a model of CMA in the mouse, i.e., congenital deficiency in CA II [CA(II)D]. In female CA(II)D mice, CA IV specific activity but not CA IV immunoreactivity was upregulated in the renal cortex, specifically in microdissected PCTs. Western blot analysis showed higher expression of CA IV immunoreactive protein in renal membranes from males than in those from females.

Animals↗

Identification of the HSV-1 genome by "Dot Blot hybridization" in the geniculate ganglion of rabbits.

Herpes simplex Virus type 1 (HSV-1) was inoculated into 48 rabbits by 3 different routes: 10 rabbits were dosed by mouth, 18 rabbits injected in the tongue and 14 injected in the perineurium of the facial nerve at its entrance into the stylomastoid foramen. Some of the animals were killed after a week and others after three weeks. Facial palsy was produced in none of the cases. Seroconversion was demonstrated in the peripheral blood of 100% of the inoculated animals. Cultures of macerate of the facial nerve and geniculate ganglion, as well as of the ipsilateral medulla, were negative. DNA from HSV-1 was found by "Dot Blot hybridization" technique in 30% of the macerates of the geniculate ganglion and facial nerve and in 60% of the medulla macerate in those animals killed after one week and in 0% of both samples in those killed in the third week. The fact that the HSV-1 could be isolated in the geniculate ganglion of the facial nerve continues to support the possibility of this virus as the causal agent for facial palsy, either as a single disease or associated with other symptoms.

Animals↗

Extended supraglottic laryngectomy for primary base of tongue carcinomas.

A retrospective review of 56 patients with a primary base of tongue carcinoma was undertaken to determine the value of supraglottic laryngectomy. All the patients had a supraglottic laryngectomy and a total of 77 neck dissections. Forty-three (76.8%) patients received post-operative radiotherapy. The incidence of local recurrence was 23.2%, neck relapse being seen in 16.1% of patients. The 3 year survival was 47%. The overall survival of the whole series and by stage was not improved by combined therapy compared with surgery alone.

Adult↗

Complications of supraglottic laryngectomy for carcinomas of the supraglottis and the base of the tongue.

The medical records of patients with either a supraglottic carcinoma (n = 193) or a base of tongue carcinoma (n = 56) who underwent a supraglottic laryngectomy were studied. Because of aspiration total laryngectomy was required in 9.8% and 21.4% of patients with supraglottic and base of tongue carcinomas, respectively, being related to locally advanced stage of disease in the base of tongue and to an age older than 65 years in the case of supraglottic carcinomas. The non-decannulation rates were 23.8% and 50% in supraglottic and base of tongue tumours respectively. Post-operative radiotherapy did not influence the decannulation rate, but advanced local disease and age did. Post-operative mortality in the first month after the operation was 2.6% in supraglottic tumours and 3.6% in base of tongue tumours.

Adult↗

Contrast-enhanced magnetic resonance imaging confirmation of an anterior protein pathway in normal rabbit eyes.

PURPOSE: Contrast-enhanced proton magnetic resonance imaging (1H MRI) has been used as a quantitative, noninvasive method to corroborate a pathway for the diffusion of plasma-derived protein into the aqueous humor in the normal rabbit eye. METHODS: T1-weighted magnetic resonance images were produced over 1- to 3-hour periods after the intravenous injection of gadolinium diethylenetriamine-pentaacetic acid. RESULTS: Analysis of the images yielded the time dependence of signal enhancements within the areas of interest. The ciliary body showed an immediate sharp increase, followed by a gradual decrease in signal enhancement with time. Although a gradual increase in signal enhancement was found in the anterior chamber, no significant change occurred in the posterior chamber. A similar MRI experiment with an owl monkey produced parallel, though smaller, signal enhancements in the ciliary body and anterior chamber. Again, however, no significant change was found in the posterior chamber. CONCLUSIONS: These results support and extend those of recent fluorophotometric, tracer-localization, and modeling studies demonstrating that in the normal rabbit and monkey eye, plasma-derived proteins bypass the posterior chamber, entering the anterior chamber directly via the iris root.

Animals↗

Up-regulation of carbonic anhydrase isozyme IV in CNS myelin of mice genetically deficient in carbonic anhydrase II.

Carbonic anhydrase (CA) II is the major CA isozyme in the brain, where it participates in acid-base homeostasis, fluid transport, and myelin synthesis. The CA II deficiency [CA(II)D] mutation in the mouse results in structural changes in the glial cells in the CNS and in decreased susceptibility to seizures, but no detectable changes in myelin yield and ultrastructure. We compared the CA isozymes in brain and spinal cord fractions, as well as in purified myelin, between CA(II)D and control mice. CA(II)D resulted in a much lower total CA specific activity in all tissues examined but in higher CA IV specific activities in soluble and membrane-associated fractions and pure myelin. Western blots of purified myelin showed a band corresponding to CA IV in CA(II)D mice. This band was weak or undetectable in myelin samples from normal mice. Immunocytochemical staining demonstrated CA IV in oligodendrocytes and myelinated tracts in normal mouse brains and stronger staining of the same structures in brains of CA(II)D mutants. We conclude that CA(II)D mutation in the mouse up-regulates CNS CA IV. We speculate that this up-regulation could mitigate the effect of CA(II)D on myelin formation and maintenance.

Animals↗

Metabolic acidosis stimulates carbonic anhydrase activity in rabbit proximal tubule and medullary collecting duct.

Both membrane-bound carbonic anhydrase (CA) (isozyme type IV) and cytosolic CA (type II) activities enhance urinary acidification. We have previously shown that chronic metabolic acidosis (CMA) accomplished by NH4Cl loading with food restriction induces soluble CA activity in rabbit renal cortical homogenates. The present study was designed to assess the effect of CMA on the activity of CA isozymes in cortical and outer medullary homogenates, as well as in major proton-secreting segments of the kidney. Segments were microdissected from proximal convoluted tubules (PCT) proximal straight tubules, cortical collecting ducts, and outer medullary collecting ducts (OMCD). Total CA activity was measured by a colorimetric endpoint method, and CA IV activity was assessed from the sodium dodecyl sulfate-resistant hydratase activity. In controls, CA IV activity accounted for 3% of total CA activity in tissue homogenates. CMA induced a threefold increase in CA IV activity in cortical homogenates, in the absence of renal or tubular hypertrophy. In the PCT, CMA induced a 78% increase in total CA activity, which comprised a 178% increase in CA IV activity, and a 58% increase in CA II activity. In the OMCD, CMA induced a 53% increase in total CA (probably CA II) activity. We conclude that CMA induces CA activity in the PCT (CA II and CA IV) and the OMCD (most likely CA II) of adult rabbit kidneys. The induction of CA activity accompanies the increase in urinary acidification observed in CMA.

Acidosis, Renal Tubular↗

Quantitative pathology of the intraepithelial laryngeal neoplasia.

A clinical-histologic and morphometric study on 32 patients with precancerous laryngeal lesions was carried out. Two biopsies taken at different times were studied, and the cases in which carcinoma developed were compared with those cases in which it did not. The only clinical-histologic variable with prognostic value, related with evolution to carcinoma, was severe dysplasia. The Malignancy Grading System, which grouped together 13 clinical-histologic variables, had both high sensitivity and high specificity. On the other hand, quantitative microscopy was a more sensitive and objective method. Through the relationship between the parameters of orientation/nuclearity and Histometric Progression Index, we could separate those cases in which invasive carcinoma developed from those cases in which it did not with a sensitivity of 100% and a specificity of 82%.

Adult↗

Pressure-reducing capability of Conforma II mattress overlay.

Pressure readings over the sacral and trochanter areas were obtained on 30 healthy adult volunteers. An anatomically contoured mattress overlay (Conforma II) was compared to a standard hospital mattress. The difference in the mean pressures over the sacral areas represented a 52% reduction in pressure, whereas, a 46% pressure reduction was obtained over the trochanter area. Body weight was significantly associated with higher mean pressures.

Adult↗

Electrolyte excretion and sodium intake.

Established essential hypertension is characterized by normal equilibrium between the intake and renal excretion of sodium. Urinary sodium excretion is interrelated with that of other ions, such as potassium and calcium, and that the response of blood pressure to salt ingestion can be conditioned by the simultaneous intake of varying levels of those ions. The authors address three aspects: the correlations between urinary excretion of sodium and calcium and sodium and potassium in a population of untreated essential hypertensive persons, the response of blood pressure during the escape induced by exogenous mineralocorticoid administration in mild essential hypertension, and the effect of intravenous calcium gluconate infusion on sodium excretion and renal function. The first part shows that sodium excretion is closely correlated with that of other ions in essential hypertension, and the second part shows that, to escape from the sodium-retaining effect of a mineralocorticoid, mild hypertensive subjects must have increased blood pressure within or near the cutoff point that defines salt sensitivity. Of interest, the elevation in blood pressure takes place while sympathetic nervous activity is blunted. The third part provides evidence to explain one of the mechanisms by which calcium influences renal function and enhances renal sodium excretion. The intrarenal effects of low doses of calcium are dependent on the renal production of prostaglandins.

Atrial Natriuretic Factor↗

Rostrocaudal changes in neuronal cell size in human lateral vestibular nucleus.

A cytoarchitectonic and morphometric study of the human lateral vestibular nucleus (LVN) is presented. In sagittal sections, the LVN appears as a triangular cell group rostrally located near the motor trigeminal nucleus and caudally near the vestibular root. The estimated volume is 13.49 mm3 with a neuronal population of 25,046 cells and 1855 neurons/mm3 in density. The average neuronal cross-sectional area changes from a minimum caudally (380.02 +/- 7.23 microns 2) to a maximum rostrally (825.16 +/- 25.10 microns 2). Four types of neurons can be observed: small (< 200 microns 2), medium (200-500 microns 2), large (500-100 microns 2) and giant or Deiter's cells (> 1000 microns 2). The small and medium cells constitute 62%, large cells 26% and the giant cells only 12% of the neuronal population.

Adult↗

Antimicrobial activity determined in strains of Bacillus circulans cluster.

Wild-type strains of the genus Bacillus were screened for antimicrobial activity. Two strains exhibited antimicrobial activity against Micrococcus luteus and were identified as Bacillus polymyxa MIR-23 and Bacillus circulans MIR-13. Bacillus polymyxa MIR-23 was active against Escherichia coli, Pseudomonas aeruginosa and Aspergillus niger, whereas Bacillus circulans MIR-13 did not show activity against these microorganisms. Bacillus subtilis ATCC 6633 and B. polymyxa ATCC 10401 were used as standard antibiotic-producer strain and showed different antimicrobial profiles and yields from B. polymyxa MIR-23. The different antimicrobial profile of the two selected strains could possibly be used as a taxonomic marker.

Anti-Bacterial Agents↗

Antihypertensive effect of nitrendipine in the hypertensive patient with renal impairment.

Calcium antagonists exert several characteristic effects on the kidney that potentiate their antihypertensive effect. The objective of the present study was to investigate the effectiveness of nitrendipine in the presence of different degrees of renal impairment. Two groups of hypertensive patients were included in the study. Group 1:10 patients with arterial hypertension secondary to chronic renal parenchymatous disease and adequately controlled with a diuretic and/or a beta-blocker who were switched to nitrendipine. These patients were then followed monthly for 1 year. Group 2:24 patients diagnosed as having essential hypertension who presented values of urinary albumin excretion above 30 mg/day after a minimum of 3 years of adequate blood pressure control with a diuretic and/or a beta-blocker. Patients were randomly assigned to continue with the same therapy or to switch to nitrendipine for 1 year. In both groups nitrendipine was as efficacious as standard therapy for controlling blood pressure and did not induce changes in renal hemodynamics. Nitrendipine did not modify the level of proteinuria in group 1, nor the urinary excretion of albumin in group 2. These results seem to indicate that nitrendipine can be safely used in patients with arterial hypertension and different degrees of renal function impairment.

Adult↗