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Biomedical subjects

A Castro

Publications and source records attributed to A Castro.

At least 37 records · Page 2Linked to original sources
PubMed1991

Rhinoplasty saw: a modified design.

One of the instruments used for osteotomies of the nasal bones in rhinoplasty is the saw. During the initial sawing movements, it is not uncommon to make multiple cuts in the bone. To avoid this problem, we have designed a modification of the Joseph's saw. The new design essentially fixes the saw along a single axis, producing a single and precise bone cut. This saw is useful for basal and superior osteotomies in rhinoplasties and is especially indicated in secondary rhinoplasties.

Equipment Design↗
PubMed1991

Effects of endothelin on renal haemodynamics and segmental sodium handling in conscious rats.

The effects of endothelin (100 and 600 pmol/kg) on renal plasma flow (RPF), glomerular filtration rate (GFR), sodium excretion (UNa V) and segmental sodium handling were investigated in conscious rats. Low-dose endothelin decreased renal plasma flow by 26% without affecting glomerular filtration rate and sodium excretion. High-dose endothelin reduced renal plasma flow, glomerular filtration rate, sodium excretion and lithium clearance by 57, 45, 38 and 52%, respectively. The fall in sodium excretion was not due to a direct effect of endothelin on tubular sodium transport since sodium excretion corrected by glomerular filtration rate and fractional proximal and distal sodium reabsorption did not change throughout the study. These results indicate that the impairment in renal perfusion is responsible for the antinatriuretic effect of endothelin in conscious rats.

Animals↗
PubMed1991

A randomized controlled trial to evaluate the effectiveness of homeopathy in rheumatoid arthritis.

Forty-four patients with active Rheumatoid Arthritis were entered into a 6-month double-blind trial comparing homeopathy and placebo. The treatments were generally equally effective in most assessments. Statistically significant improvements were produced, however, in 3 of 5 and 2 of 5 results respectively assessed in homeopathic and placebo treated groups. There was no statistically significant difference between groups. Adverse effects were scarcely and comparably reported in both groups and did not require a change in therapy.

Arthritis, Rheumatoid↗
PubMed1991

[Platelets and migraine. Correlation between biochemical markers of platelet aggregation and serotonin].

The correlation between the biochemical markers of platelet activation and serotonin in migraine was investigated. The beta-thromboglobulin (beta-TG), platelet factor 4 (PF-4) and serotonin levels in 105 patients with migraine were measured. The results confirmed an increase in beta-TG and PF4 levels and a reduction in serotonin levels during the migraine attacks. However, we did not find a significant correlation between these fluctuations. These findings suggest the existence of extraplatelet mechanism in the pathophysiology of migraine.

Adolescent↗
PubMed1990

[A study of 158 cases of acute delta hepatitis].

We have prospectively studied 158 cases of acute hepatitis delta observed during the last 7 years in a general hospital. Among them 136 were male and 22 female. The mean age was 22.7 years with a range between 16 and 61 years. The epidemiologic factors were drug addiction by parenteral route in 145 cases (92%), sexual transmission in 5 (3%), post transfusional in 2 (1%) and unknown in 6 (4%). With respect to the delta type infection, 105 cases (66%) were coinfections with type B and delta, and 53 patients had a type delta superinfection (34%). The clinical course was a fulminant hepatitis in three cases (two cases of coinfection B and delta an one case of delta superinfection), and an acute benign hepatitis in 155 patients. The follow-up of 118 patients revealed that 96% of coinfections by type B and delta evolved to the chronicity showing findings of active chronic hepatitis or hepatic cirrhosis. It should be noted that in 4 cases of superinfection delta type (11%) the HBsAg was negative after several months of positivity. In these patients the level of transaminases normalized and the hepatic histology evidenced alterations of chronic active hepatitis (2 cases) and hepatic cirrhosis (2 cases) without identification of tissular delta antigen.

Acute Disease↗
PubMed1990

Induction of tumor necrosis factor and cytotoxicity by macrophages exposed to lactoperoxidase and microperoxidase.

Peroxidases are involved in a number of cytotoxic reactions. Murine thioglycollate-induced peritoneal macrophages were exposed to either lactoperoxidase or microperoxidase in vitro. At a concentration of 17.7 microM, both of these enzymes induced between 100 and 200 units of tumor necrosis factor (TNF) per 0.1 ml. Furthermore, these substances were able to stimulate macrophages to kill 3T12 target cells in a dose dependent manner at concentrations of 0.177 microM to 17.7 microM. Per cent cytotoxicity varied from 20% up to 75% at the higher concentrations. It was concluded that these enzymes can induce macrophages to secrete TNF and become activated to the cytotoxic state.

Animals↗
PubMed1990

Successfully treated candida sinusitis in an AIDS patient.

An AIDS patient with a subdural empyema as a complication of candida sinusitis is presented. Clinical features resembled those of invasive aspergillosis or phycomycosis. Microbiological diagnosis was established by blood cultures, sinus cultures, and histopathological examination. An aggressive surgical approach first to the sinuses and then to the subdural space, together with fluconazole produced a satisfactory result.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Direct vascular effects in the rat of the vehicles used for the intravenous and oral administration of cyclosporin A.

1. The contraction and relaxation responses to the polyoxyethylated vehicles currently used for the intravenous and oral administration of cyclosporin A in allograft recipients were studied in isolated rat aorta. The results were compared with those obtained with commercially available cyclosporin A for intravenous administration. 2. None of these compounds affected resting tension, noradrenaline-induced contraction or endothelium-independent relaxation produced by sodium nitroprusside or bumetanide. However, they all reversed the relaxation induced by acetylcholine, carbamylcholine or adenosine 5'-triphosphate, by a factor of approximately 66%. 3. This reversal of relaxation was unaffected by indomethacin and did not require the presence of cyclosporin A in the vehicles, and was completely abolished by L-arginine (3 x 10(-5) mol/l). 4. It is concluded that vehicles used for commercial preparations of cyclosporin A interfere with the synthesis of endothelium-derived relaxing factor at an early stage during which L-arginine is made available for enzymatic degradation.

Administration, Oral↗
PubMed1990

Urinary excretion of endogenous digitalis-like natriuretic substances in healthy subjects. Effect of sodium load.

In the current study digoxin-like immunoreactivity (DLIA), Na-K-ATPase inhibition and natriuretic activity of urinary extracts from 10 healthy volunteers following a low and a high-sodium intake, respectively, were measured. Detectable urinary DLIA (46.1 +/- 5.6 ng eq digoxin/day), Na-K-ATPase inhibition (182.9 +/- 22.7 nmol eq oub/day) and natriuretic activity (UNaV: 0.38 +/- 0.11 microEq/min) were observed during the low-sodium diet period in all subjects. High-sodium diet was associated with a significant increase in DLIA (87.9 +/- 9.2 ng eq digoxin/day, p less than 0.001) which parallelled changes in Na-K-ATPase inhibition (359.8 +/- 51.9 nmol eq oub/day, p less than 0.005) and natriuretic activity (UNaV: 1.33 +/- 0.3 microEq/min, p less than 0.025). These results support the contention that DLIA is related to NH.

Adult↗
PubMed1990

[Platelet function in tension headache].

The possibility of abnormal platelet function in patients with tension headache was evaluated with serial plasmatic measurements of serotonin, beta-thromboglobulin and platelet factor 4. In 40 patients with tension headache we found increased serotonin, thromboglobulin and platelet factor 4 levels during the painful phases as compared with the asymptomatic phases. These data might indicate that an increased platelet aggregation plays some role in the pathogenesis of tension headache.

Adult↗
PubMed1990

[Prevalence and concurrence of several coronary risk factors in a sample of adolescents at a high school in the community of Madrid].

A prospective study of cardiovascular heart disease (CHD) risk factors was carried out in 80 adolescents aged 14-15 and 15-18. Girls had higher cholesterol levels. Sex-age-related differences were reported for apolipoproteins (apo) AI levels. Age did not have any significant influence on triglycerides, apo B and apo AI/apo B ratio, and seems to be related to the fact that the majority of the sample had a pubertal index of 4. The smoking prevalence was around 27%. The scarce concurrence of some risk factors suggest acceptable protection levels against future CHD.

Adolescent↗
PubMed1989

[Sézary syndrome: morpho-immuno-phenotypic, cytogenetic and molecular characterization].

The immunologic, cytogenetic and molecular data from a patient with Sézary syndrome are reported. Immunohistochemical analysis disclosed 90% helper CD4 cells and 10% CD8 cells. One of the most significant cytogenetic abnormalities was a t(7; 14) translocation at the level of the 7p13-15 and 14q11 bands, just where the T-cell receptors are located. At the molecular level, rearrangements of the alpha (in 14q11 chromosome), beta (in the 7q32) and gamma (in the 7p15) receptors were found. The translocation between chromosomes 7 and 14, at the level of the mentioned bands, could be responsible for some of the rearrangements found at the molecular level.

Chromosomes, Human↗
PubMed1989

Antidepressant action of imipramine and iprindole in mice is enhanced by inhibitors of enkephalin-degrading peptidases.

The implication that opioid peptides are involved in the action of the antidepressants imipramine and iprindole was investigated in mice by using the forced swimming test as an experimental model of depression. Both the drugs were found to shorten the immobility time in this test. This effect of imipramine and iprindole was reversed by the opiate antagonist naloxone. Moreover, when subeffective doses of either imipramine or iprindole were given together with an intracerebroventricular injection of an inhibitor of their degradation (thiorphan or bestatin), the immobility time was again decreased. Interestingly, the reduction of the time of immobility was found to be not related to the effect of the drugs on locomotor activity. These data might be taken as further evidence for the involvement of opioid peptides in the pharmacological action of antidepressant drugs.

Animals↗
PubMed1989

Serum IgA antibodies in HSV asymptomatic genital infections.

Cervico-vaginal swabs and serum samples from 81 women without herpes-associated clinical symptoms were examined for virus isolation and for the presence of IgA antibodies to herpes simplex virus (HSV) using the indirect fluorescent antibody technique. Nineteen of the 81 women were followed up for 2 years. Blood samples and swabs from cutaneous lesions were obtained from another group of 20 women (medical staff) with herpes labialis. By analysing the specific anti-HSV IgA antibodies, a higher geometric mean titre (GMT) was found in women with positive HSV-2 isolation (GMT = 380.03), as opposed to the GMT observed in women with negative HSV-2 (GMT = 63.43) or positive HSV-1 isolation (GMT = 55.15). Results from the longitudinal study also demonstrated that positive virus isolation always correlated with a marked rise in serum IgA antibody to HSV.

Adolescent↗