PubMed Health⌕ Search

Biomedical subjects

A Acosta

Publications and source records attributed to A Acosta.

At least 37 records · Page 2Linked to original sources
PubMed1997

Effects of the antipsychotic drug sulpiride on reproductive hormones in healthy premenopausal women: relationship with body weight regulation.

Metabolic and endocrine abnormalities secondary to hyperprolactinemia, such as hypogonadism and hyperandrogenicity, may be involved in the excessive body weight gain induced by antipsychotic drugs in women. The present study was conducted in healthy premenopausal women, in order to detect an endocrine imbalance secondary to antipsychotic drug administration, which, if sustained in the long term, might be involved in the development of obesity. After a control menstrual cycle, sulpiride (200 mg/day) or placebo was nonblindly administered for 28 days; blood lipids and the serum levels of the following hormones which are involved in body weight regulation were assessed at days 3, 10, 20 and 26 of the cycle: prolactin (PRL), 17-beta estradiol (E2), progesterone (P4), follicle stimulating hormone (FSH), luteinizing hormone (LH), free testosterone (T5), dehydroepiandrosterone sulfate (DHEAS), cortisol, tyrotropic hormone (TSH), tetraiodothyroxine (T4), and the areas under the insulin and glucose tolerance curve. During sulpiride administration, the following changes were observed when compared to placebo administration: PRL levels were significantly increased; E2 levels were significantly reduced at days 10 and 20; P4 levels were significantly reduced at day 20, and the area under the glucose tolerance curve was significantly increased. The other variables were not significantly affected. The body weight gain was higher during sulpiride than during placebo administration, but it did not reach statistical significance, perhaps because the period of treatment was too short. The decrease in the serum levels of E2 during sulpiride administration is probably secondary to hyperprolactinemia. It affects the E2/T5 ratio in the direction of increasing the androgenic activity, as observed in women with well-established obesity. This effect, along with a genetic predisposition, increased appetite, hypoactivity and ignorance of proper dietary habits, may explain the excessive weight gain and obesity observed in women during chronic treatment with sulpiride and other antipsychotic agents.

Adult↗
PubMed1997

Eosinophilic ulcer of the oral mucosa: report of a recurrent case on the tongue.

Eosinophilic ulcer of the oral mucosa (EUOM) is an uncommon lesion that usually affects the tongue. The lesion is benign and self-limiting, develops rapidly and usually disappears after several weeks without treatment. Microscopically, it contains a diffuse polymorphous cell infiltrate composed mainly of eosinophils. The cause of EUOM is unknown, but the condition has been attributed to trauma. We now describe a case of EUOM on the lateral surface of the tongue with recurrence on its dorsal surface 3 years later. The occurrence of multiple lesions, whether at the same time or subsequently as reported here, makes a purely traumatic origin rather unlikely and suggests that there may be a predisposition of some patients to develop EUOM. Eosinophilic ulcer of the oral mucosa (EUOM) is an uncommon lesion that is very rarely reported in the dermatological literature. It usually affects the tongue and presents clinically as an ulcer with elevated and indurated borders. Recognition is important because it often mimicks tongue cancer; however, the lesion is benign and self-limiting, develops rapidly and usually disappears after several weeks without treatment. Usually the ulcer occurs in a single episode, but the possibility of recurrence at other sites has been poorly emphasized.

Adult↗
PubMed1994

Detection of alkaline phosphatase in venom by blotting methods.

Venom alkaline phosphatase was detected using a blotting method following electrophoresis. The enzyme gave strong reactions in some venoms, but was absent in other venoms, some within the same species. The mol. wt of the enzyme is close to 100,000 and its pI is between 3.6 and 4.8. The enzyme was inactivated by EDTA and 2-mercaptoethanol, and lost activity by freezing and thawing. Endogenous venom alkaline phosphatase can interfere with alkaline phosphatase-based detection methods. Pre-screening for endogenous venom alkaline phosphatase is recommended prior to using alkaline phosphatase-based detection methods when studying snake venom.

Agkistrodon↗
PubMed1994

Experimental model of graft vs. host disease in non-immunosuppressed F1 (CBA/J x C57BL/6) mice.

The experimental model of graft vs. host disease (GvHD) has a potential use in the evaluation of different manipulation procedures of the immune system applicable to development of vaccines. In the present study an experimental model of GvHD in F1 (CBA/J x C57BL/6) mice by means of the parenteral inoculation of spleen lymphoid cells from parental male CBA/J to 10-day-old animals (experimental group) was developed. Animals inoculated with Medium 199 (n = 42) (Medium 199 group), or with splenic lymphoid cells either from the hybrids (n = 16) (F1 group), or from mice of the inbred strain Balb/c (n = 10) (Balb/c group) were used as controls. In all groups body and spleen weights, relative spleen index (RSI), and spleen index (SI) were determined. Additionally, histopathologic and morphometric studies were done in the spleens of the animals studied. Significant increases in body and spleen weights, RSI, and lymphocytic perimeter and area were associated with distinctive splenic GvHD lesions found in the experimental group. The experimental SI value was higher than twice the SI value of any of the control groups. We conclude that ours is a useful model of GvHD with many potential applications in the field of vaccine production.

Animals↗
PubMed1994

Sequential study of an experimental model of graft vs. host disease (GvHD) in non-immunosuppressed F1 (CBA/J x C57BL/6) mice.

In order to determine the optimal day for the evaluation of an experimental model of GvHD in F1 mice and the histopathologic evolution of the lesions in different organs, we studied 10-day-old F1 (CBA/J x C57BL/6) mice inoculated with splenic lymphoid cells of the male parental CBA/J strain (n = 42) that were sacrificed between 1 and 14 days postinoculation. The evolution of the relative spleen index (RSI) and the histopathologic lesions in different organs were also determined. F1 mice inoculated with Medium 199 were used as controls. Significant RSI increases (p < 0.0001) were found in the experimental group between 2 and 14 days postinoculation, with a peak at the eighth day, associated with the most severe histopathologic lesions in the organs studied. We suggest the eighth day as the optimal time for evaluation of this experimental model.

Animals↗
PubMed1994

Histopathologic and humoral study of Balb/c mice inoculated with BCG by different routes.

With the aim of determining the distribution and humoral immunogenicity of the bacillus Calmette-Guérin (BCG) administered by the oral (O), intravenous (IV) and subcutaneous (SC) routes, we studied 54 male Balb/c mice weighing 17-22 g that had been inoculated with BCG (10(6) CFU) by the O (n = 18), IV (n = 18) and SC (n = 18) routes. At weekly intervals we determined the distribution of the microorganism using histopathological techniques including Ziehl-Neelsen staining. Serum samples of the same animals were analyzed by ELISA and Western blot to determine the antibody response to the microorganism. In all groups, distinctive histopathologic lesions harboring the microorganism were found. Using the SC route the lesions were located at the inoculation site, whereas there was systemic dissemination with the O and IV routes, being more prominent with the latter. Anti-BCG antibodies were detected by ELISA in all groups; this response was more intense in the IV group, followed by the SC and O groups. In the Western blot analysis, reactivity against multiple bands and the predominant recognition of a 65 kd band in all groups was observed.

Administration, Oral↗
PubMed1994

Sialic acid acceptors of different stages of Trypanosoma cruzi are mucin-like glycoproteins linked to the parasite membrane by GPI anchors.

Trans-sialidase catalyzes the transference of sialic acid from host to the Trypanosoma cruzi surface. Here, we characterize the sialic acid acceptors of this protozoan parasite as mucin-like molecules, which are anchored to the membrane by glycosylphosphatidylinositol. The mucins isolated from the insect stages differ from the mucins isolated from the mammalian stages in size and reactivity to monoclonal antibodies, suggesting that they are formed by variable polypeptide chains and/or O-linked carbohydrate structures.

Animals↗
PubMed1993

Functional and morphological features of spermatozoa microaspirated from the epididymal regions of cynomolgus monkeys (Macaca fascicularis).

In most species examined to date, spermatozoa mature during transit through the epididymis to become functionally competent to swim progressively, fertilize oocytes, and produce viable offspring. In the studies presented here, the status of spermatozoa obtained from the regions of the epididymis of the cynomolgus monkey (Macaca fascicularis) was examined. Epididymal fluid was collected by microaspiration from the caput, corpus, and cauda regions. The spermatozoa obtained were evaluated for morphology, motion parameters, and tight zona pellucida binding and were compared to spermatozoa collected by electroejaculation. Epididymal and ejaculated sperm differed morphologically only in the location of the cytoplasmic droplet. Motile sperm recovered by swim-up procedure exhibited a significantly higher proportion of sperm with more distal cytoplasmic droplets than the original aspirated samples (p < 0.02). Poor duration of movement was most noticeable for corpus spermatozoa, and to a lesser degree for cauda spermatozoa, when the motion parameters of velocity, linearity, and amplitude of the lateral head were examined. Zona pellucida binding was decreased only for sperm microaspirated from the caput region; sperm obtained from the corpus and cauda regions bound comparably to those collected via electroejaculation. These results suggest that by the time cynomolgus sperm reach the corpus region of the epididymis, they are functionally competent for tight zona binding. However, these nonhuman primate sperm may not complete the metabolic changes requisite for sustained sperm motility until reaching the most distal regions of the epididymis.

Animals↗
PubMed1993

Nonparallel secretion of pepsinogen and acid by gastric oxyntopeptic cells of the toad (Bufo marinus).

Pepsinogen and HCl secretion in the amphibian stomach are performed by a single cell type, the oxyntopeptic cell. These functions were studied in gastric mucosae of toads (Bufo marinus) mounted in Ussing-type chambers. HCl and peptic activity of luminal fluid were measured by titration and proteolysis of albumin, respectively. Distribution of pepsinogen in the gastric mucosa was heterogeneous, activity being highest in the proximal part of the stomach. Zymogen granules in the oxyntopeptic cell were more abundant in the deeper cells of the glands and in the fundus. On stimulation, the granules were released into the lumen of the glands by exocytosis. Histamine, forskolin, or carbachol alone each induced an increase in HCl and pepsinogen secretion. Carbachol after maximal histamine or forskolin stimulation produced an extra increase in both secretions that was greater for pepsinogen response. Similarly, joint addition of carbachol and histamine was more potent than histamine alone for both parameters; however, the effect was greater on pepsinogen release. Pretreatment with cimetidine blocked HCl and pepsinogen responses to carbachol but did not affect responses to forskolin. Addition of omeprazole to forskolin-stimulated mucosae uncoupled the two secretions, inducing a total inhibition of HCl secretion with a slight reduction in pepsinogen secretion. Thus pepsinogen release, similar to HCl secretion, is sensitive to cAMP and Ca(2+)-dependent secretagogues. However, the action of Ca2+ would require the previous elevation of cAMP induced by the different secretagogues. In such a case, the increase in intracellular Ca2+ would result in a nonparallel activation of the two secretions.

Animals↗
PubMed1993

[Comparison of acid and pepsinogen secretion control by oxyntopeptic cell of amphibians].

Pepsinogen and HCl secretion in the amphibian stomach is performed by a single cell type, the oxyntopeptic cell. The distribution of pepsinogen in gastric mucosa of Bufo marinus is heterogeneous and higher concentrations are located in the fundus. Both secretions respond to the same secretagogues. Histamine induces the highest response for the two secretions. Carbachol alone, without the endogenous histamine component, has a small effect. Forskolin and 8Br-cAMP have a similar effect to histamine. The Ca2+ ionophore, A23187, and the diacylglycerol analogue, octanoylacylglycerol (OAG) have a small effect on both secretions as carbachol. Joint addition of histamine and carbachol, or forskolin and carbachol, or of OAG and 8Br-cAMP induce a potentiated response for the two secretions. Quantitative analysis of responses and study of the relationship between them during stimulation with histamine plus carbachol revealed a non parallel and uncoupled pattern of stimulation for acid and pepsinogen secretions.

Animals↗
PubMed1991

Glycoinositol phospholipids from American Leishmania and Trypanosoma spp: partial characterization of the glycan cores and the human humoral immune response to them.

The glycoinositol phospholipid (GIPL) profiles of American Leishmania spp. (L. mexicana and L. braziliensis), Leishmania donovani, and American Trypanosoma spp. (T. cruzi and T. rangeli) were compared. The major GIPLs in these parasites include tetraglycosyl-, pentaglycosyl-, and hexaglycosylphosphatidylinositol. These were partially identified by their comigration by high-performance thin-layer chromatography with purified L. major GIPLs, gas-liquid chromatography of the monosaccharides released after aqueous HF treatment, N-acetylation and methanolysis, sensitivity to exoglycosidases, and antibody absorption on several specific natural haptens. Members of the genus Leishmania have two other highly polar glycolipids, while the T. rangeli glycolipid profile was quite different from those of other kinetoplastids that were studied. On a weight basis, the glycan core of L. major GIPL-1 is the most reactive, followed by GIPL-3 and GIPL-2. Antibodies to the core glycans of GIPL-1, GIPL-2, and GIPL-3 were present at a low titer in the serum of every normal individual studied, while elevated GIPL-2 antibody levels were present in 80 to 100% of T. cruzi-, T. rangeli-, or L. donovani-infected patients, with lower values being found for GIPL-3 (30 to 60%) and GIPL-1 (30 to 50%). Except for GIPL-2 antibodies, which were mainly located on immunoglobulin G (IgG) and IgM, GIPL-1 and GIPL-3 antibodies were mainly distributed in IgM, with lower reactivity present in IgG. Antigen-antibody binding was very selectively blocked with Gal(alpha 1-3)Man, or Gal(beta 1-4)Man, Gal(alpha 1-3)Gal, and Gal(alpha 1-6)Gal for GIPL-1, GIPL-2, and GIPL-3 antibodies, respectively.

Animals↗
PubMed1991

[Hematologic changes in rats treated with high doses of vitamin K3 (menadione)].

The present study describes the effect of high doses of vitamin K3 (8-30 mg/kg) administered daily by intramuscular injection during seven days; on blood smear, red blood cells (RBC) and concentration of hemoglobin (Hb) counts, value of hematocrit (Ht), mean corpuscular hemoglobin concentration (MCHC), reticulocyte and erythroblast counts, total and differential counting of leukocytes (WBC) and total and fractionated serum bilirubin concentration of albino male rats. Results were then compared with findings in normal rats treated with the same doses of sodium bisulfite. In animals treated with vitamin K3 a statistically significant decrease in the number of erythrocytes and in the concentration of Hb, Ht and MCHC was found together with a concomitant increase of erythroblast and reticulocyte counting. In regard to the blood smear, it was observed that erythrocytes vary in their hemoglobin content, size, shape and in their staining properties (polychromatophilia) where as the leukocytes were found to be morphologically normal, but in an increased number. Lymphocytes occasionally showed azurophil granules. Platelets assumed irregular shape and in normal amounts. The leukocytes count showed leukocytosis with marked neutrophilia, eosinophilia, lymphocytosis and monocytosis. Also, the presence of clinical jaundice with an increase of the serum "indirectly-reacting" bilirubin was also observed. These findings indicate that hypervitaminosis K3 induces a marked hemolytic microcytic hypochromic anemia and changes in the white blood cells count. Further studies will be pursued in order to obtain a better understanding of the causes and/or the mechanisms that induce these alterations in the blood cells.

Analysis of Variance↗
PubMed1991

[The hematological manifestations in 111 patients with systemic lupus erythematosus].

Hematologic alterations are frequent in SLE. The hematologic changes of 111 patients diagnosed as suffering from SLE are described, associating them to 89 clinical, biological and hystological variables. The most frequent alteration was normocytic and normochromic anemia. Coombs positive hemolytic anemia appeared in 10% of the cases. Approximately 20% of patients had leukopenia. Lymphopenia was observed during the active period of the disease. Mild thrombocytopenia is common, as well as quality changes of the platelets. The sedimentation rate is high in nearly all patients with SLE and this is a non-specific index of the disease activity. These changes have seldom been described in our area.

Adolescent↗
PubMed1990

Defect in the tissue cellular immune response: experimental visceral leishmaniasis in euthymic C57BL/6 ep/ep mice.

In BALB/c mice, successful defense against visceral leishmaniasis is T cell dependent, expressed by tissue granuloma formation, and probably mediated by macrophages activated by cytokines, including gamma interferon (IFN-gamma). C57BL/6 ep/ep (pale ear) mice, which reportedly exhibit impaired IFN-gamma production, were challenged with Leishmania donovani to determine the outcome of infection in a euthymic host with an apparent defect in lymphokine secretion. In BALB/c and normal C57BL/6 mice, L. donovani liver burdens peaked at 2 weeks and were largely eliminated by 4 weeks. In contrast, in pale ear mice, infection progressed until after 4 weeks and persisted at high levels at 8 weeks. The failure to resolve hepatic infections was not related to deficiencies in (i) Thy-1+, L3T4+, or Lyt-2+ T cells; (ii) IFN-gamma secretion; (iii) liver tissue Ia expression; (iv) macrophage antimicrobial capacity; or (v) antileishmanial antibody production. However, despite the anticipated influx of mononuclear cells into livers, these cells were not properly focused on the parasitized Kupffer cells, the inflammatory infiltrate receded prematurely, and mature granulomas failed to develop. These results suggest that there is a cellular immune defect at the tissue level and emphasize the critical role of granuloma formation in successful resolution of systemic intracellular infections.

Animals↗