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P Sesma

Publications and source records attributed to P Sesma.

At least 37 records · Page 2Linked to original sources
PubMed1998

Relationship between epithelial and connective tissues in the stomach of the frog Rana temporaria during metamorphosis: an ultrastructural study.

In the course of metamorphosis of the stomach of Rana temporaria tadpoles there is a marked increase in the amount of active mesenchymal fibroblasts and extracellular matrix underlying the regenerating gastric epithelium. At the onset of metamorphosis, a thick PAS-positive basement membrane is developed around the epithelial component of the mucosa, formed by the apical, degenerating larval epithelium and the basal, regenerative epithelial cords. Under the electron microscope, a folded basement membrane is usually revealed under the apical degenerating epithelium while a compact basement membrane (up to 1-2 microns thick), forming both patches and more extensive areas, is frequently seen around the regenerative glandular cords. Cytoplasmic processes, extending from both the epithelial and mesenchymal fibroblastic cells, cross the basement membrane and make physical contact between the two cellular types. At mid-metamorphosis areas of thick PAS-positive basement membrane are still observed around the differentiating glandular outlines, before disappearing completely at late metamorphosis. The probable involvement of intertissue interactions between epithelium and connective elements in the morphogenesis, proliferation and differentiation of secondary, definitive frog stomach is discussed. Early contacts between epithelium and phagocytes, probably related to the invasion of epithelium by the phagocytic cells, have also been observed.

Animals↗
PubMed1998

[Decisions regarding cholesterol-lowering therapy in the elderly: the experience in a lipid clinic and a review of the literature].

BACKGROUND: Therapy for hypercholesterolemia is long known one of the interventions with higher benefit on coronary heart disease secondary prevention and on primary prevention in middle-age high-risk people. Data about elderly persons are more scarce. The aim of this work is to study elderly patients sent to a Lipid Clinic, focusing on Serum Lp (a) levels and criteria to prescript cholesterol-lowering drugs. We have reviewed current knowledge to discuss and to clarify these criteria. METHOD: Observational study. Review of the medical charts from the patients sent to the Lipid Clinic. Elderly patients were compared with middle-aged persons attended to the same Clinic. RESULTS: From 348 total Lipid-Clinic cohort 72 (20.7%) patients were more than 65 years old (31 male). A 3 months or longer follow-up was available in 49/72 and 36/49 were taking cholesterol-lowering drugs. Among these 36, 21 had coronary disease; the other 15 had, at least, another risk factor, besides dyslipidemia. Serum Lp (a) level were higher in older group (38.7 +/- 36.9 mg/dl, median 29, vs 26.3 +/- 24.2, median 18 mg/dl, p < 0.01). Considering the accepted cardiovascular risk threshold (Lp (a) > 30 mg/dl), difference were found only in women. Coronary disease was present in 79 patients followed 3 months or longer and 24/79 were more than 65 years old. Twenty-one of them were taking cholesterol-lowering drugs, vs 50 from the 55 younger (pNS). The reasons for no drug-therapy were similar in both groups. CONCLUSIONS: Coronary heart disease or cardiovascular risk factors association were the criteria used for starting cholesterol-lowering drug therapy. Published evidence supporting this therapeutic approach is reviewed. There were not found age related differences for cholesterol-lowering drugs prescriptions in patients suffering coronary disease. Serum Lp (a) level were higher in elderly sample because of the increase in older women; it could be linked to the postmenopausal hormonal state.

Age Factors↗
PubMed1997

[Anticentromere antibodies and lung disease without skin involvement].

Anticentromere antibodies are closely related to systemic sclerosis and basically to limited cutaneous form. Two patients with different forms of lung disease, positive anticentromere antibodies and absence of the characteristic skin involvement of the systemic sclerosis are presented.

Aged↗
PubMed1997

An immunocytochemical and ultrastructural study of the larval anterior intestine of the frog Rana temporaria, with especial reference to endocrine cells.

Endocrine cells of the larval intestine of Rana temporaria tadpoles have been identified by argyrophilic, immunocytochemical and electron-microscopical techniques. Scarce endocrine cells have been found in both the short non-absorptive zone immediately following the stomach, and in the rest of the anterior intestine. Endocrine cells are frequently seen to extend a cytoplasmic process towards the lumen. Immunoreactivity for serotonin, somatostatin, bombesin and cholecystokinin-8 has been detected. According to the ultrastructural traits of the endocrine granules, three larval intestinal endocrine populations have been differentiated.

Animals↗
PubMed1996

[Usefulness of an ELISA for the diagnosis of Streptococcus pneumoniae in patients with pneumonia].

BACKGROUND: To evaluate the etiologic role of Streptococcus pneumoniae in a series of patients with community-acquired pneumonia. METHODS: By an direct ELISA the presence of Streptococcus pneumoniae capsular polysaccharide antigen in serum and urine from 125 patients with community pneumonia was evaluated. Horseradish peroxidase-labeled polyvalent antiserum (Omniserum) was used. Working dilutions of reagents were determined by checkerboarding. Positive control antigen consisted of Pneumovax 23 and negative control consisted of serum and urine samples from healthy subjects. RESULTS: Antigen detection was positive in 8 of 124 (6.45%; CI 95%: 2.80-12.30%) serum samples and in 15 of 115 (13.04%; CI 95%; 7.51-20.68%) urine samples concentrated 25-fold. Pneumococcal pneumonia was diagnosed by ELISA in 17 cases (13.60%; CI 95%: 8.15-20.95%), of which one had positive blood culture. The sensitivity of the ELISA in 24 patients with definite pneumococcal pneumonia diagnosed in this series was 70.83%. CONCLUSION: These results suggest that the ELISA is a useful method in rapid diagnosis of Streptococcus pneumoniae in patients with pneumonia.

Adolescent↗
PubMed1995

Neuroendocrine diffuse system of the respiratory tract of Rana temporaria: an immunocytochemical study.

The neuroendocrine cell population of the respiratory system of Rana temporaria has been studied by means of immunocytochemical methods at the light-microscopic level. Isolated or clustered endocrine cells have been found in the epithelium of the buccal cavity, glottis, larynx, and lung. Nine different types of endocrine isolated cell types can be distinguished according to their immunoreactivity to several regulatory peptides [calcitonin, substance P, bombesin, peptide histidine isoleucine (PHI), cholecystokinin (CCK), and endothelin 1] and neuroendocrine markers (7B2, chromogranin, and serotonin). Neuroepithelial bodies are innervated clusters of cells simultaneously immunoreactive for serotonin and 7B2. Nerves and/or neurons have been detected in different regions of the respiratory system using antibodies against protein gene product 9.5, serotonin, calcitonin gene-related peptide (CGRP), substance P, PHI, helodermin, and CCK.

Animals↗
PubMed1995

Metamorphic changes in the stomach of the frog Rana temporaria tadpoles.

The histological transformation of amphibian stomach during metamorphosis was studied in the frog Rana temporaria. The earliest metamorphic changes occur shortly before regression of the cloacal piece of tail and appearance of forelegs. Autolysis of primary, larval epithelial cells and activity of phagocytes lead to regression of the apical mucosa, which is shed into the gastric lumen. Histogenesis takes place from the very beginning of metamorphosis in the basal region of the mucosa; undifferentiated, regenerative cells, arranged in small compact cords and surrounded by a thick basement membrane, give rise to secondary lining epithelium and glands. Lining epithelial cells differentiate into a typical mucosecretory epithelium. Oxyntic cells present in larval glands are substituted by both ion- and protein-secreting oxyntic-peptic cells. During metamorphosis, connective and muscular tissues markedly increase, a submucosa, not present in larval tadpoles, gradually develops. A muscularis mucosae is also formed and the muscular propria becomes thicker. At late metamorphosis, folded structures involving both mucosa and submucosa develop, increasing the luminal surface as in adults. Removal of the larval gastric mucosa and its replacement by a new, adult-type definitive one, together with development of peripheral connective and muscular tissues, account for metamorphosis of tadpole stomach.

Animals↗
PubMed1995

Neuronal nitric oxide synthase immunoreactivity in the respiratory tract of the frog, Rana temporaria.

Physiological and histochemical studies have recently supported the notion that nitric oxide (NO) is the transduction signal responsible for the non-adrenergic, non-cholinergic relaxation of the vasculature as well as the airways of the mammalian lung. We report the presence of immunoreactivity to NO synthase (NOS) in nerve cell bodies and nerve fibres in the neural plexus of the buccal cavity and lungs of the frog, Rana temporaria, using the indirect immunocytochemical technique of avidin-biotin and the NADPH-diaphorase technique. The neural ganglia located next to the muscle layer and within the connective tissue of the buccal cavity were partially immunoreactive for NOS. In the lungs, NOS immunoreactivity occurred in nerve cell bodies, as well as in both myelinated and unmyelinated nerve fibres. Fine nerve fibres immunoreactive to NOS were observed within the muscle fibre bundles and next to the respiratory epithelium. Both the presence of NOS immunoreactivity and the positive histochemical reaction for NADPH-diaphorase in the neural plexus of amphibian respiratory tract suggests a broad evolutionary role for NO as a peripheral neurotransmitter.

Animals↗
PubMed1995

[Hemorrhagic shock and fulminant hepatic failure associated with valproate].

Fulminant hepatic failure is an uncommon adverse effect of valproate treatment. Despite an increased use of valproate, since the drug was introduced in 1978, a decline in the number of reported cases has been observed. Here a case of hemorrhagic shock and fulminant hepatic failure in a patient treated with valproate is presented. We emphasize the diagnostic difficulties from the point of view of recognition of the clinical manifestations as well as the biochemical monitoring.

Anticonvulsants↗
PubMed1994

Endothelin-like immunoreactivity in midgut endocrine cells of the desert locust, Locusta migratoria.

Endothelin-1-like immunoreactivity has been found in endocrine cells of the midgut of the desert locust Locusta migratoria. Several antisera have been directed against the whole molecule and its C-terminal sequence. Endothelin-1-immunoreactive cells are present in the main region of the midgut (ventriculus) and in the midgut caeca but not in the ampullae through which the malpighian tubules drain. Endothelin-1-like immunoreactivity colocalizes with FMRFa immunoreactivity in the cells of the main region of the midgut but not in those in the midgut caeca. Endothelin-1-immunoreactive cells are present not only in adults but also throughout the five instars of posthatching development.

Animals↗
PubMed1994

Myoendocrine-like cells in invertebrates: occurrence of noncardiac striated secretory-like myocytes in the gut of the ant Formica polyctena.

The occurrence of myoendocrine-like cells investing the ampullar draining region of Malpighian tubules and neighboring midgut and hindgut regions of the ant Formica polyctena is reported. These striated muscle cells show small electron-dense endocrine-like granules (130 +/- 0.95 nm) in addition to myofilaments and ordinary organules of the myocytes. Apart from their contractile function, such ultrastructural features suggest a regulatory role for these cells, as is the case of vertebrate myoendocrine cells. As far as we know, the ant secretory myocytes reported here constitute the first description of myoendocrine cells among invertebrates, as well as the first report of secretory, striated muscle cells outside the heart in the animal kingdom.

Animals↗
PubMed1994

An immunocytochemical study of the respiratory system of Podarcis hispanica (Reptilia).

The endocrine cells and nerves of the respiratory tract of the reptile Podarcis hispanica were investigated by immunocytochemistry under light microscopy. Immunoreactivities were more numerous in the lung than in the trachea. In the tracheal epithelium, endocrine cells immunoreactive to PHI, PYY, and Leu-enkephalin were detected, while immunoreactivity to serotonin, calcitonin, CGRP, PHI, and Leu-enkephalin was found in pulmonary endocrine cells. Numerous nerve fibers positive to NSE, PGP9.5, chromogranin, tyrosine hydroxylase, calcitonin, CGRP, bombesin, substance P, VIP, NPY, and PYY were found in the lungs. In addition, neurons positive to NSE and PGP9.5 were also found. Immunoreactivities to PHI and PYY in cells and to NSE, PGP9.5, chromogranin, tyrosine hydroxylase, calcitonin, CGRP, and PYY in nerves, were reported first in the respiratory system of reptiles.

Animals↗