Search PubMedSearch

Biomedical subjects

M L Sanz

Publications and source records attributed to M L Sanz.

At least 19 recordsLinked to original sources

A randomized trial of late reperfusion therapy for acute myocardial infarction. Thrombolysis and Angioplasty in Myocardial Infarction-6 Study Group.

BACKGROUND: Experimental and observational clinical studies of acute coronary occlusion have suggested that late reperfusion prevents infarct expansion and facilitates myocardial healing. The purpose of this trial was to assess whether infarct vessel patency could be achieved in late-entry patients and what benefit, if any, can be demonstrated. METHODS AND RESULTS: In a double-blind fashion, 197 patients with 6 to 24 hours of symptoms and ECG ST elevation were randomly assigned to tissue-type plasminogen activator (100 mg over 2 hours) or placebo. Coronary angiography within 24 hours was used to determine infarct vessel patency status. Patients with infarct-related occluded arteries were then eligible for a second randomization to either angioplasty (34 patients) or no angioplasty (37 patients). Ventricular function and cavity size were reassessed at 1 month by gated blood pool scintigraphy and at 6 months by repeat cardiac catheterization. The primary end point, infarct vessel patency, was 65% for plasminogen activator patients compared with 27% in the placebo group (p less than 0.0001). There were no differences between these groups in ejection fraction or infarct zone regional wall motion at 1 or 6 months. At 6 months, infarct vessel patency was 59% in both groups. In the placebo group, there was a significant increase in end-diastolic volume from acute phase of 127 ml to 159 ml at 6-month follow-up (p = 0.006) but no increase in cavity size for the plasminogen activator group patients. Coronary angioplasty was associated with an initial 81% recanalization success and improved ventricular function at 1 month, but by late follow-up no advantage could be demonstrated for this procedure, and there was a 38% spontaneous recanalization rate in the patients assigned to no angioplasty. CONCLUSIONS: The study demonstrates that it is possible to achieve infarct vessel recanalization in the majority of late-entry patients with either thrombolytic therapy or angioplasty. Thrombolytic intervention had a favorable effect on prevention of cavity dilatation and left ventricular remodeling, but there are no late benefits on systolic function after thrombolysis or coronary angioplasty. The conclusions concerning overall potential benefit of applying late reperfusion therapy will require data from large-scale trials designed to assess mortality reduction.

Angioplasty, Balloon, Coronary

Binding of a 15 kDa glycoprotein from spermatozoa of boars to surface of zona pellucida and cumulus oophorus cells.

A highly purified 15 kDa glycoprotein isolated from ejaculated spermatozoa was used to raise antisera in female rabbits. An indirect immunofluorescence technique was used to detect the antigen in the seminal vesicle tissue and on the acrosomes of ejaculated, native and capacitated, boar spermatozoa. No immunoreactivity was detected on cells of the seminiferous tubules (spermatogonia, spermatocytes, and spermatids), on spermatozoa in the ductus epididymis and in cells of the epididymal and testicular tissues. These observations support the view that the 15 kDa protein is produced in the seminal vesicle secretory epithelium, and is attached to the sperm plasma membrane during the exposure of spermatozoa to seminal vesicle compounds. The observations that the antigen remained on the acrosome of ejaculated spermatozoa after capacitation and blocked sperm-oocyte binding in vitro suggest that the antigen plays a role in sperm-egg interactions. The strong immunoreactivity exhibited by cumulus cells after incubation of antisera with the porcine egg surrounded by cumulus cells shows the possible importance of the 15 kDa glycoprotein for contact of spermatozoa with cells of the cumulus oophorus surrounding the egg.

Animals

Response of isolated cat middle cerebral artery to platelets: effect of endothelium removal.

1. Platelets induced an endothelium-independent contraction in isolated cat middle cerebral artery under resting conditions. In precontracted segments they evoked an endothelium-dependent contraction followed by a relaxation. 2. The contraction induced by serotonin was unaffected by endothelium removal either in the absence or in the presence of a previous tone. 3. The contractile response to platelets and serotonin under resting tension was blocked in the same way by ketanserin, methysergide or cyproheptadine. 4. After adding the platelets, serotonin could be measured in the bath medium. 5. These results suggest that the endothelium plays a minor role in the contraction induced by platelets, which is partly due to serotonin release.

Animals

Different influence of endothelium in the mechanical responses of human and cat isolated cerebral arteries to several agents.

The present work was undertaken to elucidate the role of the vascular endothelium in the changes of isometric tension elicited by different compounds in isolated cylinders of human and cat cerebral arteries and cat pulmonary arteries. Endothelium removal by rubbing significantly reduced the relaxing response to acetylcholine (ACh) of isolated segments of all the arteries. The same treatment did not modify the contraction elicited by 5-hydroxytryptamine (5-HT) in the human and cat cerebral segments but increased the contractile effect of the amine in cat pulmonary arteries. The mechanical responses to vasopressin, ATP and adenosine in isolated segments of cat cerebral arteries were unaffected after removing the endothelial layer. L-Arginine, but not D-arginine (10(-5) M), enhanced significantly the relaxation induced by increasing doses of ACh in unrubbed cat cerebral arteries whereas it did not modify the response to ACh in rubbed ones. However, L-arginine had no effect on the dose-response curve to 5-HT in both kinds of preparation and did not change the tone in precontracted unrubbed cat cerebral segments. These results suggest that the endothelium of the cerebrovascular bed plays a minor role in regulating the mechanical response induced by several vasoactive agents, although it retains its ability to produce an endothelium-derived relaxing factor.

Acetylcholine

Beta-receptor decrease in bronchial asthma.

Sinesterases that intervene in cAMP and oGMP equilibrium in the cytoplasm of mast cells are activated by the adrenergic system through beta-receptors. A study was made on 96 atopic patients with mono sensitization to Dermatophagoides pteronissinus, in 3 groups. Radioligands were used to quantitate the number of beta receptors. In the control group mean no/cell was 541, bronchial symptomatic patients had 327 and nasal symptomatics 348. Asymptomatic patients were similar to controls. The results were similar with pollen-sensitive patients. Beta receptor decrease is a consequence of clinical allergy in atopic patients and is secondary to the immunological events that follow antigen-antibody reactions and cell membrane changes.

Adenylyl Cyclases

Number of beta-receptors in patients allergic to Dermatophagoides pteronyssinus.

This study was carried out on 96 atopic patients with monosensitization against Dermatophagoides pteronyssinus and 30 control individuals. The patients were divided into 3 subgroups: 27 asymptomatic patients, 27 patients who only presented nasal symptomatology, and 27 patients with marked bronchial symptomatology. Total serum IgE, antigen-specific histamine release, and the number of beta 2-adrenergic receptors in peripheral blood lymphocytes in all patients were determined. The control group presented the highest number of beta-receptors in comparison with the bronchial symptomatic and nasal symptomatic patients. However, asymptomatic patients presented numbers of beta-receptors similar to controls, with no significant differences between both groups. No significant correlation was found between beta-adrenergic receptors and levels of total serum IgE. On the other hand, correlation between beta-receptors and specific histamine release was detected only in symptomatic nasal patients. It can be postulated that the decrease in beta-receptors is a consequence, and not the cause, of atopy.

Adult

Influence of seasonal variations on histamine release and other immunological parameters in pollinosis.

One hundred and fifty-six pollen-sensitive patients with sensitization to grass pollen only were chosen for this study; 65 patients were allergic to Dermatophagoides, while 45 were non-allergic subjects with no atopic history. The following tests were carried out on all patients: histamine release of total blood, basal histamine, total histamine, determination of total IgE and specific IgE (RAST) serum levels, serum hemagglutinating antibodies and skin tests. Seasonal increase of IgE was observed, with post-seasonal fall; 50% of the cases reached normal values. However, RAST as a semiquantitative method did not prove to be useful in the detection of variations in specific IgE levels. During pollination, an increase in titers in pollen-sensitive subjects was seen. This was attributed to a humoral immune response epiphenomenon which was independent of IgE. The histamine release test was significantly greater during pollination in pollen-sensitive subjects. The total of stored histamine increased during the months of allergenic exposure.

Animals

Number of beta-receptors in rhinitic pollinic patients.

The study was carried out on venous blood from 67 patients with seasonal rhinoconjunctivitis caused by sensitization to grass pollen and 30 control individuals. Total IgE determination, antigen-specific histamine release test against two concentrations of Phleum pratense, and quantification of beta 2-adrenergic receptor numbers in lymphocyte membrane of peripheral blood were done on all patients. Those pollinic patients who were asymptomatic at the time of the study had 500.07 +/- 237.27 receptors/cell; no significant differences were established with the control group, with 541.53 +/- 123.63 receptors/cell. However, both the control group and asymptomatic patients had receptor numbers which were significantly higher than those of symptomatic pollinic patients, with 376.81 +/- 158.65 receptors/cell (p < 0.01 and p < 0.05, respectively). The average decrease in number of receptors in symptomatic pollinic patients was 30.42% in relation to controls and 24.65% in relation to asymptomatic patients. Within the subgroup of pollinic patients, studied both in and out of season, the number of beta 2-adrenergic receptors had an average decrease of 13.22% during pollination, with 363.7 receptors/cell. Once the pollination season was over, this figure increased to 419.1 receptors/cell, establishing significant differences with p < 0.025. The number of beta 2-adrenergic receptors did not correlate with total seric IgE figures or with antigen-specific histamine release. These data indicate that the decrease of these receptors does not constitute the causal factor of atopic diseases; it seems more likely to be a consequence of the same.

Adolescent

Study of IgE-dependent basophil releasability in allergic patients.

For this study, venous blood from 160 patients with a diagnosis of asthma and/or rhinitis was used. Histamine release test (H.R.T.) with anti-IgE at 1/5 and 1/25 dilutions and with causal antigen in the case of atopic patients (144) was carried out on all patients. Basophils from atopic patients released more histamine than those from nonatopic patients (p < 0.001). Basophils of atopic patients released more histamine with 1/5 anti-IgE dilution (p < 0.01), while non-atopic patients did so with the 1/25 dilution (p < 0.05). On grouping atopic patients according to positive or negative results in Ag-specific histamine release, 14% of patients presented negative Ag-specific H.R.T. and 85.7% of the cases did not respond to anti-IgE stimulus; this was 12% of the total number of atopics. On the other hand, 17% of the patients studied did not show positive histamine release against anti-IgE and 70.6% of them had negative Ag-specific release. As for the effect of age on IgE-dependent histamine release, the group of patients who presented greater releasability corresponded to those older than 6 years of age. The discrepancies observed between the clinical history, skin tests, serum IgE and antigen-dependent histamine release in some patients could be related to the individual basophil ability to release histamine. Therefore, this basophil releasability evaluation has an important practical application in discerning false negatives in antigen-specific H.R.T.

Adolescent

Seasonal influence on serum and receptor-bound IgE in pollinosis.

Analysis of the correlation between bound and free IgE in 32 patients with pollinosis before and during the pollen season disclosed no correlation between bound and free IgE in rhinitic patients before the pollen season, while there was correlation during the season. In the asthmatic patients there was good correlation before the pollen season rather than during it.

Antigens, Differentiation, B-Lymphocyte

Evidence of endothelial dysfunction in angiographically normal coronary arteries of patients with coronary artery disease.

Acetylcholine causes endothelium-dependent dilation of normal arteries in most animal species. The effect of acetylcholine on normal human coronary arteries is controversial. Pathologic studies and epicardial echocardiography have shown that diffuse atherosclerosis is often present despite angiographic evidence of discrete coronary artery disease (CAD). Therefore, we postulated that acetylcholine would cause vasoconstriction of coronary arteries that are angiographically normal in patients with CAD. Coronary artery diameter, measured by automated quantification of digitized cineangiograms, was determined before and after the intracoronary infusion of 0.2 mM acetylcholine at 0.8-1.6 ml/min. The diameter of stenotic or irregular segments of six atherosclerotic coronary arteries decreased from 1.80 +/- 0.42 mm before acetylcholine to 1.26 +/- 0.46 mm after acetylcholine (p = 0.0025). Acetylcholine had a significantly different effect on the diameter of two groups of coronary arteries that are angiographically normal. Acetylcholine caused a 0.16 +/- 0.09-mm increase in the diameter of 14 normal coronary arteries in patients without CAD, whereas it caused a 0.26 +/- 0.12-mm decrease in the diameter of 14 normal coronary arteries in patients with CAD (p less than 0.01). Thus, the normal response to intracoronary acetylcholine is vasodilation, suggesting that endothelium-derived relaxing factor is released from normal human coronary endothelium. The vasoconstrictive effect of acetylcholine in the angiographically normal coronary arteries of patients with CAD suggests the presence of a diffuse abnormality of endothelial function.

Acetylcholine

Results of the in vitro follow-up of immunotherapy.

With the advances made in allergological diagnosis, thanks to the application of various in vitro immunological techniques, we have also learnt more about the immunological modifications produced during the course of the immunotherapy. Among the techniques which will detect immunological changes is the histamine release test, which will show a decrease in antigen-specific histamine release. On the other hand, both total IgE and IgG4 are modified in the course of this immunotherapeutic treatment.

Follow-Up Studies

Variability of quantitative digital subtraction coronary angiography before and after percutaneous transluminal coronary angioplasty.

Quantitative coronary angiography has been proposed as a means of reducing observer variability in the interpretation of coronary angiograms, especially before and after percutaneous transluminal coronary angioplasty (PTCA). Analysis of 13 consecutively acquired biplane digital subtraction angiograms before and after PTCA was undertaken to determine intra- and interobserver variability of absolute lesion diameter, relative videodensitometric cross-sectional area, automated percent diameter stenosis and visual percent diameter stenosis using a new fully automated quantitative computer program. The reliability of single-view measurements was also assessed. Both before and after PTCA, measures of absolute diameter showed less interobserver variability than densitometry, percent automated diameter stenosis and percent visual diameter stenosis measurements (before, r = 0.95, 0.83, 0.86, 0.70; after, 0.95, 0.88, 0.81, 0.62, respectively). Relative videodensitometric cross-sectional area correlated poorly with images from the orthogonal view (r = 0.46). These data suggest that quantitative angiography reduces variability from visual estimates; of all quantitative angiographic measurements, the highest interobserver reproducibility is achieved using absolute lesion diameter both before and after PTCA, probably because no operator interaction is needed to identify a "normal" segment. Unselected, single-view quantitative arteriography is poorly reproducible using videodensitometry. Therefore, automated determination of absolute lesion diameter in at least 2 projections provides the most reproducible evaluation of coronary lesions both before and after PTCA.

Angioplasty, Balloon

[Nutritional and immunologic state of patients undergoing heart valve surgery].

A series of 60 consecutive patients treated by heart valve replacement surgery under extracorporeal circulation were reviewed. Poor nutrition was assessed in 28% of these cases, the cardiac index in these patients being significantly smaller than in operated patients with normal nutritional states (2.07 +/- 0.8 as against 2.46 +/- 0.7, p less than 0.01). Furthermore, 58% of those with poor nutrition presented postoperative complications: mediastinitis, wound infection, ventricular arrhythmias or secondary pulmonary infection. One death occurred in this group. Postoperative complications in patients with normal nutritional states developed in only 6% and there were no deaths. Duration of hospital stay was significantly longer in patients with poor nutrition (p less than 0.05). Apart from immunoglobulin levels, all immunologic parameters underwent postoperative modifications related to nutritional state. Physiopathologic hypotheses are proposed as well as a programme for increasing nutritional intake in patients in a precarious metabolic state which predisposes them to complications.

Adult

[Determination of the lymphocytic and oncofetal antigen subpopulations in patients with adenocarcinomas of the stomach and of the colon and rectum (author's transl)].

The authors present a study of 50 patients with adenocarcinomas of the colon and rectum, patients with gastric adenocarcinomas, and 30 healthy individuals as a control group. In all subjects the following parameters were determined: total number of lymphocytes in the peripheral blood, T lymphocytes, T-active lymphocytes, and B lymphocytes. A study of the test for lymphoblastic transformation (TTL) with phytohemagglutinin (PHA) stimulation and the determination of alpha-fetoprotein (AFP) and carcino-embryonic antigen (CEA) were also carried out. In patients with gastric adenocarcinoma the results revealed a lymphopenia, especially at the expense of T and T-active lymphocytes, as well as a depression (in 73 per cent) of the lymphocytic response to the PHA stimulation. Patients with carcinoma of the colon showed significant results in the T-active lymphocyte population. In both neoplastic situations the determination for alpha-fetoprotein was negative, while the CEA presented a clear correlation with the evolutive stage of the tumor, being more demonstrative in the tumors located in the colon and rectum.

Adenocarcinoma

Immunosuppressive effect of corticosteroids on rabbit's humoral and cellular response.

The immunosuppressive effect of two of the most used steroids, 16-Methylen-prednisolone and betamethasone, was studied in rabbits sensitized to bovine serum albumin (BSA). In the steroid treated animals the hemagglutination and precipitation titres obtained in Boyden's test and gel-diffusion respectively, were strongly decreased as compared with the controls. The Arthus reaction was also inhibited. No response was detected in the lymphocyte transformation test (LTT) against the antigen (BSA) in the treated animals, and also the PHA induced transformation was suppressed but not completely abolished. A remarked decrease in the number of circulating mononuclear cells was observed in the treated animals. The number of T rosette-forming cells was also strongly decreased, but the percentage of B cells bearing IgG on their membrane detected by immunofluorescence offered only a slight decrease as compared with the controls. All these changes were observed earlier and more intensely in the Betamethasone treated rabbits.

Animals

Food allergy as a cause of rhinitis and/or asthma.

We studied the histories of patients who had visited our Department during the last 5 years, presenting food allergy with exclusively respiratory symptoms (18.5%). We studied the correlation between IgE levels and the histamine release test and the type of food implicated. Seventy-seven percent of patients presented sensitization to one food, and 23% presented polysensitization. We found that foods such as snails and eggs have a strong predilection for the bronchial tree as the shock organ. High total IgE was found in 85.2% of patients. The histamine release test was positive in 66% of cases. We conclude that this is a highly sensitive method for the in vitro diagnosis of food allergy.

Allergens