Félix Jacobo Tapia

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The lymphokine profiles were determined in the skin lesions of the three distinct clinical forms of American cutaneous leishmaniasis (ACL), using a reverse transcriptase polymerase chain reaction (RT-PCR) and primers for various lymphokines. The message for interferon-gamma (IFN-gamma), tumour necrosis factor-beta (TNF-beta), and IL-8 was expressed in the(More)
American cutaneous leishmaniasis is characterized by a spectrum of clinical manifestations. These include localized, often self-healing single lesions, intermediate forms which frequently produce mucosal lesions and often show exaggerated delayed-type hypersensitivity (DTH), and the rare diffuse cutaneous leishmaniasis in which no reaction of protective(More)
Thirty-two tumors (31 pancreatic and one jejunal) all associated with severe watery diarrhea, increased VIP levels in blood and most with hypokalemia, were investigated. The VIP content of tumor tissue ranged from 23 to 15,000 pmol/g. VIP immunoreactive cells were detected histochemically in 24 of 28 tumors investigated, PP immunoreactive cells in 11 of 28(More)
The ultrastructural localization of antigens recognized by an antiserum raised against formaline-killed Sporothrix schenckii yeast cells was investigated on yeast and mycelial phases of the fungus. Immunogold procedures revealed that these antigens were located on the cell surface of both growth phases. Labelling was heterogeneous and involved areas of(More)
Merkel cells are specialized skin receptor cells, characterized by their particular location in the epidermis and close association with nerve terminals. Although they can be distinguished ultrastructurally by their small, electron-dense secretory granules, there is no specific and reliable method for identifying them by light microscopy. Using antibodies(More)
Neuron-specific enolase (NSE) is a neuronal form of the glycolytic enzyme enolase, which was first found in extracts of brain tissue, and was later shown to be present in APUD (amine precursor uptake and decarboxylation) cells and neurons of the diffuse neuroendocrine system but not in other peripheral cells. 90 neuroendocrine neoplasias (APUDomas)(More)
We characterized key leukocyte immunophenotypes in the liver and spleen of naturally infected dogs from an area in Venezuela endemic for leishmaniasis. Dogs were classified as symptomatic or asymptomatic after serologic and physical analysis. Symptomatic dogs showed a higher parasite burden in the liver and spleen than asymptomatic dogs. The livers of(More)
The American cutaneous forms of leishmaniasis include immune-responder individuals with localised cutaneous leishmaniasis (LCL) and non-responder individuals with diffuse cutaneous leishmaniasis (DCL). Patients with intermediate or chronic cutaneous leishmaniasis (ICL) have increased morbidity due to the length of their illness, atypical forms and areas of(More)
BACKGROUND The skin is an important component of the neuroendocrine-immune axis. Several studies have shown that stress exacerbates skin disorders, affecting the function of sebaceous glands, keratinocytes, epidermal Langerhans cells and other cells, having an impact on the pathogenesis of many immunologically associated skin diseases. In American cutaneous(More)
The use of protein A- and IgG-conjugated colloidal gold staining methods for the immuno-localisation of peptide hormones and neurotransmitters at light- and electron microscope level are described and discussed. Bright-field and dark-ground illumination modes have been used to visualise the gold-labelled antigenic sites at the light microscope level.(More)