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Biomedical subjects

A Castro

Publications and source records attributed to A Castro.

At least 469 records · Page 26Linked to original sources
PubMed1981

Serum prolactin levels following augmentation mammaplasty.

A prospective study to evaluate the possible relationship between augmentation mammaplasty, a chronic irritant to the breast, and serum prolactin levels was carried out. Eleven healthy female subjects were studied. Serum prolactin levels were determined twice prior to surgery and at 1 and 3 weeks after surgery. No significant change was detected in the postoperative prolactin values. In four subjects evaluated 3 months following surgery, the prolactin levels also remained unchanged. In addition, none of the women developed galactorrhea during their observation period. These results suggest that the placement of a Silastic implant for augmentation mammaplasty may not be a chronic stimulus leading to either galactorrhea or elevation of prolactin levels.

Adult↗
PubMed1981

Effect of 1 alpha-hydroxyvitamin D3 on the glucose and calcium metabolism in genetic obese mice.

In summary, it is demonstrated, for the first time, that there is a marked reduction of bone mass in ob/ob mice and this was restored by the treatment with 1 alpha-OH-D3. The effect of the sterol was accompanied by the improvement of hyperglycemia, hyperinsulinemia, and fat tissue responsibility to hormones. Thus, it is of interest to study obesity in terms of calcium homeostasis.

Animals↗
PubMed1980

[Cytomorphological study of the cerebrospinal fluid. II. Leukemias and lymphomas (author's transl)].

A cytological study of the cerebrospinal fluid from 25 patients with acute leukemias and five patients with malignant lymphomas (Hodgkin's disease and non-Hodgkin's lymphoma) has been performed. All patients had clinical manifestations of central nervous system involvement at the time of lumbar puncture. Cytological abnormalities were observed in 13 out of the 30 samples examined (positivity: 44 percent). The group of 17 patients with lymphoblastic leukemia accounted for the highest cytological positivity (12 our of 17 cases --70.5 percent--). Cerebrospinal fluid from eight patients with acute myeloblastic leukemia and from four patients with Hodgkin's disease was normal. Numerous cell atypias were found in a case of lymphocytic lymphoma. The importance of systematic cytological study of the cerebrospinal fluid in patients with leukemia in order to prevent recurrences and to control intrathecal administration of cytostatics and/or radiotherapy is stressed.

Cerebrospinal Fluid↗
PubMed1980

[Behçet's disease: report of ten cases and of a new clinical manifestation (portal vein thrombosis) (author's transl)].

Ten patients (seven males and three females) with the diagnostic criteria for Behçet's disease are reported. Symptoms began between ages 14 and 37 (mean age 27.9 years), and the time of evolution of the disease varied between one and 23 years (mean 5.7 years). Initial presentation was aphthous stomatitis (three cases), ocular inflammation (three cases), erythema nodosum (one case), arthritis (one case), thrombophlebitis (one case), and hemorrhagic proctocolitis (one case). During the course of the disease the commonest clinical manifestations were oral and genital ulcerations (100%) and ocular (70%), cutaneous (70%), articular (40%), neurological (40%), venous (40%), gastrointestinal (40%) and arterial (10%) involvement. Increased erythrocyte sedimentation rate was a constant feature in all patients. HLA-B5 antigen was determined in four patients, being positive in two of them. Cerebrospinal fluid alterations were present in the four patients with neurological involvement even though three of them never had meningeal symptoms. One patient developed portal hypertension secondary to portal vein thrombosis, and its clinical manifestations are described.

Adolescent↗
PubMed1980

[Cytomorphology of the cerebrospinal fluid. I. Tumors of the central nervous system (author's transl)].

A cytomorphological study of the cerebrospinal fluid corresponding to 42 patients with tumors of the central nervous system has been performed. The group of 31 patients with primary tumors accounted for an overall cytological positivity of 32.2 percent; according to the type of tumor cytological positivities were as follows: glioblastoma multiforme (44.4 percent); grade I/III astrocytoma (33.3 percent); oligodendroglioma (33.3 percent); ependymoma (25 percent), and meningioma (16.6 percent). In the group of 11 patients with metastatic tumors, neoplastic cells were observed in two cases (cytological positivity 18.1 percent). Cytological study of the cerebrospinal fluid is a useful diagnostic method for some primary and secondary neoplasms of the central nervous system.

Brain Neoplasms↗
PubMed1980

Quantification of digoxin by enzyme immunoassay: synthesis of a maleimide derivative of digoxigenin succinate for enzyme coupling.

We synthesized the m-maleimidobenzoyl derivative of digoxigenin-3-0-succinate (through a p-phenylenediamine bridge) as a hapten derivative directed towards coupling to sulfhydryl grouos of beta-galactosidase. Prepared enzyme conjugate had about 97% of the enzyme labeled with the hapten derivative while retaining full enzyme activity. The enzyme immunoassay for digoxin we prepared showed a maximum sensitivity of 30 pg per assay (c.v. = 3%) with minimal cross-reaction with digotoxin (3.8%). Our method for hapten conjugation to beta-galactosidase is highly efficient and is simple and easily replicated.

Cross Reactions↗
PubMed1980

Prostatic origin of tumors. An immunohistochemical study.

An immunoperoxidase technic was used to localize prostatic acid phosphatase in a variety of primary and metastatic neoplasms. The aim was to explore the histogenesis of tumors affecting the prostate gland and to demonstrate the prostatic origin of metastases in various sites. A highly specific antiserum to prostatic acid phosphatase was raised in rabbits, and the peroxidase-antiperoxidase procedure was carried out on formalin-fixed paraffin-embedded routine pathology material. All specimens from the 37 cases of known primary and metastatic prostatic carcinomas stained positively for prostatic acid phosphatase, regardless of their histologic differentiation. None of the specimens from the 44 cases of proven nonprostatic primary and metastatic tumors stained positively for prostatic specific acid phosphatase. The data suggest that demonstration of prostatic acid phosphatase by the immunoperoxidase technic is a practical, sensitive, and specific test for the prostatic origin of an otherwise unclassifiable primary or metastatic neoplasm.

Acid Phosphatase↗
PubMed1980

Nicotine antibodies: comparison of ligand specificities of antibodies produced against two nicotine conjugates.

Conjugates between bovine serum albumin and (R,S)-2-aminonicotine were produced, and these conjugates were employed in rabbits and goats for the production of nicotine antibodies. In the assay of nicotine, an 125I-tyrosine methyl ester derivative of (R,S)-6-aminonicotine was employed as radioligand. The antibody-bound derivative was separated from the free derivative by charcoal adsorption (0.5% charcoal, 0.1% dextran T-70, 0.1% bovine serum albumin pH 7.3). Among the twenty five nicotine derivatives and metabolites examined, (R,S)-6-aminonicotine gave the highest cross-reaction. Cross-reaction with cotinine, a major mammalian metabolite of nicotine, was less than 0.1% for both the rabbit-derived and goat-derived antisera. Cross-reaction by other metabolites, such as (S)-nicotine-N'-oxide, (S)-nornicotine, and N-methylpyrrolidine was less than 1%. The antibodies produced were thus highly specific to nicotine. The radioimmunoassay for nicotine showed a maximum sensitivity of 10 ng/ml in 50-microliter plasma samples for both antisera. After the smoking of a single cigarette (1.2 mg nicotine content in mainstream) the peak of blood plasma level of nicotine in the subjects varied from 20--104 ng/ml, and high levels of nicotine were not necessarily found in heavy smokers.

Animals↗
PubMed1980

Monoclonal antibodies specific for dengue virus type 3.

Mouse lymphocyte hybridomas were prepared by polyethylene glycol-mediated fusion of cells from a mouse plasmacytoma line with lymphocytes from a mouse hyperimmunized with dengue virus type 3 (dengue-3). Media from 50 hybrid colonies were screened; 46 of them showed antibody activity against dengue-3-infected cells as determined by an indirect immunofluorescent antibody technique. Dengue monoclonal antibody obtained after cloning one of these colonies demonstrated activity in hemagglutination inhibition and indirect immunofluorescent antibody assays with dengue-3 antigen, but not type 1, 2, and 4 antigens. In addition, this antibody activity could be removed from culture media only by absorption with dengue-3 antigen.

Absorption↗
PubMed1980

Practical enzyme immunoassay for plasma cortisol using beta-galactosidase as enzyme label.

Enzyme immunoassay for cortisol was developed using beta-galactosidase as an enzyme label and m-maleimidobenzoyl derivatives of cortisol, i.e. cortisol-21-m-maleimidobenzoate (CT-MB) and cortisol-21-hemisuccinate conjugated with m-maleimidobenzoic acid through p-phenylenediamine linkage (CHS-MB), as the haptens coupled to sulfhydryl groups of the enzyme. This enzyme-coupling procedure was highly efficient; over 90% of the enzyme was labeled while full enzyme activity was retained. CHS-MB-beta-galactosidase conjugate showed high immunoreactivity to antibody produced against cortisol-21-hemisuccinate-bovine serum albumin but showed poor displacement with the added cortisol. CT-MB-beta-galactosidase conjugate, however, showed not only a high immunoreactivity to the antibody but also displaced well with cortisol, showing maximum sensitivity of 1 microgram/dl with a 20-microliter sample size. Modification around the linkage of cortisol derivative resulted in high sensitivity to cortisol. Cross-reactions to cortisol-21-acetate, cortisone, and corticosterone were 150%, 10%, and 7%, respectively. The accuracy, precision and correlation with RIA of this method were satisfactory for clinical application.

Galactosidases↗
PubMed1980

Immunochemical demonstration of human chorionic gonadotrophin (hCG) in tissue of breast carcinoma.

Immunoreactive human chorionic gonadotrophin (hCG) was found in 9 of 65 surgically removed malignant breast tumours. The concentrations found ranged from 5 to greater than 500 mIU hCG/g tumour. Of the nine, seven extracts were assayed for total protein content; when expressed as mIU/mg extract protein, the hCG concentrations ranged from 0.28 - > 18.2 mIU/mg protein. Comparison of oestrogen receptor and hCG presence in the tumours showed no strong correlation. All tumours in which hCG was detected were shown to be of ductal origin. The hCG was measured by a beta-chain specific radioimmunoassay which measures only hCG even in the presence of high levels of other gonadotrophin hormones. In further study of these specimens an immunoperoxidase staining technique was used to stain for hCG in formalin-fixed sections of the same tumours assayed by RIA. This technique confirmed hCG in the positive specimens examined (tissue was available for 7 of the 8 positives) and no significant staining in any negatives. The hCG was shown to be localized within the cytoplasm and on the surface of the malignant cells but not in surrounding normal cells. This intracellular localization demonstrates that the malignant cells may produce hCG, rather than stimulating the pituitary to do so.

Breast Neoplasms↗