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J Carneado

Publications and source records attributed to J Carneado.

At least 19 recordsLinked to original sources
PubMed1999

Sodium transport kinetics, cell membrane lipid composition, neural conduction and metabolic control in type 1 diabetic patients. Changes after a low-dose n-3 fatty acid dietary intervention.

BACKGROUND: A decreased content of n-3 fatty acids in erythrocyte membrane of type 1 diabetic patients, which is inversely related to plasma levels of HbA(1c), has been reported previously. Our aim in this study was to observe the changes after a low-dose n-3 fatty acid (330 mg/day docosahexaenoic acid and 630 mg/day eicosapentanoic acid) dietary intervention in the lipid composition of cell membrane and metabolic control (measured according to plasma HbA(1c) levels). Since changes in both parameters may alter transmembrane sodium transport or influence parameters measuring target organ damage, we also studied the neural conduction quality and activity of four sodium transporters. METHODS: Eighteen type 1 diabetic patients were randomly assigned to continue their usual diet (control group) or to supplement their diet with a daily low dose of n-3 fatty acids (supplemented group). The changes between baseline and end values of the following parameters were compared: HbA(1c), lipid and phospholipid composition of cell membrane, activity of four ion carriers and neural conduction quality. RESULTS: The dietary supplementation caused statistically significant changes in membrane lipid composition, particularly an increase of C22:6 (n-3) and the total n-3 fatty acid (respectively +0.90+/-1.14% vs. -0.44+/-1.23% and +1.36+/-1.62% vs. -0.5+/-1.80%, p<0.05). After the dietary supplementation, we also observed a significant decrease of HbA(1c) (-2.00+/-1.9% vs. -0.13+/-0.48%, p<0.05), without significant changes in the dose of insulin required, an increase in the motor conduction velocity by the median nerve (+2.12 +/-1.35 m/s vs. -0.8+/-2.34 m/s, p<0.05) and a decrease of the V(max) of the Na(+)-Li(+) countertransport (-96.6+/-111.2 vs. +58.1+/-81.3 micromol/l cell/h(-1), p<0.01). CONCLUSION: A low-dose omega-3 fatty acid dietary supplementation may change the fatty acid composition of the cell membrane and improve the metabolic control of diabetes. Using this dose, we also observed a decrease of the maximal rate of Na(+)-Li(+) countertransport and a slight improvement of neural conduction.

Adolescent↗
PubMed1998

Orthostatic headache.

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Cerebrospinal Fluid Pressure↗
PubMed1997

[Hypertensive subpopulations as defined by their natriuretic response to ambulation].

BACKGROUND: The heterogeneity among patients with essential hypertension is known. We observed in an earlier study a large spread in the values of fractional excretion of sodium in a group of subjects with mild essential hypertension after ambulation, suggesting possible subgroups among them. We defined as the retainer (R) group that which presented a reabsorption index (RI = fractional excretion of sodium during supine/fractional excretion of sodium after ambulation) < 2.5 and the non-retainer (NR) group as that whose RI < 2.5. We analyzed at what level the reabsorption of Na was produced and the differences between the possible groups. PATIENTS AND METHODS: We studied 51 mild essential hypertensive patients, 22 men and 29 women, in two consecutive periods -recumbent, 90 minutes; ambulation, 90 minutes-. We calculated the clearance of creatinine and lithium, fractional proximal and distal reabsorption of Na, plasma renin activity (PRA), plasma aldosterone (ALDO) and elimination of PGE2 and kallikrein in the urine; the plasma catecholamines at the end of the recumbent position and after 10 minutes in the upright position. The study was taken after at least ten days without treatment and following a diet with free Na intake. RESULTS: We did not encounter significant differences between the retainer (n = 19) and non-retainer (32) group with regard to age, sex, body mass index or elimination of Na/24 h. The lower natriuresis in ambulation in the R group compared with the NR group is due to a higher fractional reabsorption of sodium, proximal (83.7 +/- 4.9% vs 79 +/- 5.2; p < 0.01) as well as distal (96.8 +/- 2 vs 95.3 +/- 2%; p < 0.05). The increment in the PRA was greater in the R group (1.3 +/- 1.4 vs 0.8 +/- 0.8; p < 0.05) after ambulation; in the R group showed a lower index -increment in ALDO/increment in PRA- in response to postural change although without significancy. We observed a lower elimination of PGE2 and kallikrein in the R group as compared with NR group (p < 0.05). We did not find differences with regard to plasma catecholamines. CONCLUSIONS: Ambulation allows to distinguish two groups of essential hypertensive patients according to natriuresis. The lower natriuresis in ambulation on the part of the R group could be due to the increase in PRA and therefore of the angiotensin II at the level of the proximal tubule, and to a lower activity of natriuretic hormones (PGE21 kallikrein) at the distal level.

Adult↗
PubMed1996

Erythrocyte Na(+)-Li+ countertransport in essential hypertension: correlation with membrane lipids levels.

OBJECTIVE: To examine whether Na(+)-Li+ countertransport (SLC) activity is linked to erythrocyte membrane lipid content. DESIGN: An observational case-control study. The maximal efflux rate of SLC, plasma cholesterol, triglycerides, phospholipids, low- and high-density lipoprotein cholesterol levels and the erythrocyte membrane cholesterol, phospholipids and fatty acids contents were determined both in fasting normolipaemic normotensive subjects and in hypertensive patients. METHODS: The Li(+)-stimulated Na+ efflux was measured in Li(+)-preloaded erythrocytes. Membrane cholesterol and phospholipids levels were determined by the latroscan technique. Membrane fatty acids were identificated by gas chromatography. Several derived indices were also obtained. RESULTS: Erythrocyte membranes of hypertensive patients showed an increase in cholesterol: phospholipid ratio and a decrease in the total amount of polyunsaturated fatty acids, mainly at the expense of arachidonic acid and docosatetraenoic acid. SLC activity was higher in hypertensive patients and correlated positively with the plasma triglycerides level and negatively with the ratio of C20:4 to C20:3. CONCLUSION: Our data from untreated normolipaemic hypertensive patients show that a higher SLC activity was accompanied by parameters that indicate a lower membrane fluidity.

Adult↗
PubMed1995

Description of a new quotient that may differentiate blood pressure profiles in essential versus Cushing's syndrome-related hypertension.

Since the presence or absence of a nocturnal decrease in blood pressure values (BP) may suggest an increased risk of visceral complications or the existence of secondary hypertension, several methods have been described for evaluating the BP profile. Nevertheless, a universally accepted system to evaluate this item has not yet been established. Our aim in this study was to test different dispersion quotients (DQ) which estimate the differences between the mean of each hour, and the mean of all the readings in the 24 h period. These quotients may be employed regarding systolic (SBP) or diastolic (DBP) blood pressure, and may be referred to the whole period of 24 h, or to the subperiods morning (m), afternoon (a) or night (n). We have studied two non selected groups of essential (n = 20) or secondary (Cushing's syndrome, n = 17) hypertensives. We observed a marked decrease in these quotients, particularly DQ-SBP and nDQ-SBP, in secondary hypertensives (respectively 10.2 +/- 2.9 vs 15.6 +/- 4.2 and 11.8 +/- 5.0 vs 20.5 +/- 6.3, p < 0.0001), thus indicating, a blunted nocturnal fall of BP in these patients. Also the DQ and particularly DQ-SBP, nDQ-SBP and nDQ-DBP, showed a high positive and negative predictive value, sensitivity and specificity for pertaining to the Cushing's syndrome group (respectively: 0.75, 0.88, 0.88, 0.75; 0.86, 0.82, 0.77 0.90; and 0.78, 0.84, 0.82, 0.80).

Adolescent↗
PubMed1994

[Influences of hyperinsulinemia in the lipid profile of hypertensive patients].

BACKGROUND: Hypertension and dyslipemia are associated with a greater frequency than that randomly expected. The increase in insulinic resistance hyperinsulinemia is one of the factors implicated in the pathogenesis of this association. In the present study the lipid profile of hypertensive patients is analyzed according to the degree of insulinemia. METHODS: The lipid profile (total cholesterol, fraction linked to low density lipoproteins cLDL, high density cHDL, triglycerides and plasma apolipoproteins A1 and B were determined in 87 patients with essential high blood pressure. Moreover an oral overdose of 75 g of glucose was administered with determinations of glycemia, insulinemia and C peptide at the time of glucose administration, 60 and 120 minutes. RESULTS: Upon separation of the hypertense patients into two groups according to the insulinemia achieved following an oral overload of glucose, those hypertensives with a greater degree of insulinemia showed a significant increase in triglycerides (p < 0.05) and also a significant decrease in cHDL (p < 0.001). The hypertensive patients with lower insulinemia showed a significant increase in total cholesterol (p < 0.05) and fraction linked to LDL although the latter was not significant. CONCLUSIONS: Two different lipid profiles may be observed in hypertensive patients: one linked to hyperinsulinemia and characterized by an increase in triglycerides and a decrease in cHDL and another with no relation with hyperinsulinemia which is manifested by an increase in total cholesterol and cholesterol transported by the LDL.

Adult↗
PubMed1994

Ambulatory blood pressure monitoring in physicians working in a hospital: is there an increase in the number of subjects with high workplace blood pressures?

Sixty-two physicians from our hospital who were normotensives, as supported by casual blood pressure measurements, underwent 24-h blood pressure monitoring which included their normal work, home rest and sleep periods. During working hours, 19% of the subjects showed mean diastolic and/or diastolic plus systolic blood pressures higher than those admitted as normal by the WHO for casual measurements for out of work subjects. Both mean systolic and diastolic blood pressure measurements, during the work at the hospital, were significantly higher in males (P < 0.01 and P < 0.005, respectively) than the mean of the readings obtained during the 24-h period, but this phenomenon did not occur among the females. Male's mean systolic (129.8 +/- 10.6 vs. 117.1 +/- 9.7 mmHg, P < 0.0001) and diastolic pressures (83.4 +/- 8 vs. 74.9 +/- 7.3 mmHg, P < 0.001) were significantly higher during the working period in relation to those of the female group. Discussing the influence of the kind of work on blood pressure, we came to the conclusion of the existence in our environment of a group of subjects (generally males), presenting high blood pressure values during their working period at the hospital and normal or borderline values during the rest of the day. This should be of interest, since it has been reported that subjects with high workplace blood pressure have an increased risk of hypertension and target-organ damage.

Adult↗
PubMed1993

Cell membrane fatty acid composition in type 1 (insulin-dependent) diabetic patients: relationship with sodium transport abnormalities and metabolic control.

We have studied the fatty acid composition of erythrocyte membrane phospholipids in nine Type 1 (insulin-dependent) diabetic patients and nine healthy control subjects. Cell membranes from the diabetic patients showed a marked decrease in the total amount of polyunsaturated fatty acids (19.0% +/- 2.2 vs 24.6% +/- 1.4, p < 0.0001) mainly at the expense of docosahexaenoic acid C22:6(n3) (2.9% +/- 1.1 vs 5.3% +/- 1.3, p < 0.001), and arachidonic acid C20:4n6 (12.0% +/- 1.6 vs 15.1% +/- 0.6, p < 0.0005). Conversely, the total amount of saturated fatty acids was significantly increased (p < 0.05) and the polyunsaturated/saturated ratio was decreased in the Type 1 diabetic patients (p < 0.00 005). Neither the time from diagnosis, nor C-peptide levels, correlated with parameters indicating a poor metabolic control of Type 1 diabetes. However, C22:6(n-3) and total n-3 content significantly correlated with HbA1c (r = -0.79 and r = -0.88, respectively, p < 0.01), fructosamine (r = -0.71 and r = -0.74, respectively, p < 0.05), and Na+-K+ ATPase activity (maximal rate/Km quotient) (r = 0.78 and r = 0.71, respectively, p < 0.05). In conclusion we have found marked alterations of cell membrane lipid composition in Type 1 diabetic patients. These cell membrane abnormalities in lipid content were related to sodium transport systems and to poor metabolic control. Either diet, or the diabetic state, might be responsible for the observed cell membrane abnormalities. A dietary intervention study might differentiate the role of diet and diabetes in the reported cell membrane alterations.

Adult↗
PubMed1990

[Cervical actinomycosis starting as a monoparesis of the upper left extremity].

We present a case of cervical actinomycosis which due to its localization, unusually low and posterior, made its debut as a monoparesis and which due to its unexpected size, marked aggressiveness, and radiologic image mimicked a tumor. We have not found in the literature this kind of presentation up to date. Although sulphur grains were not observed, empiric treatment could be started based on the Gram stain information. Culture was delayed 15 days, but we could promptly obtain reliable diagnosis thanks to pathologic study. Associated Pseudomonas aeruginosa was isolated.

Abscess↗