Publications by authors named "Herrera-Velit P"

Objectives.: To produce recombinant single-chain antibodies from alpaca that will bind to the excreted-secreted (ES) Fasciola hepatica antigen with high affinity and specificity, so as to develop new diagnostic technologies of human and animal fascioliasis.

Materials And Methods.

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Introduction: The etiology of several hepatocellular carcinoma (HCC) cases remains largely unknown. Although Fasciola hepatica has been associated with liver fibrosis in Latin America, it has not yet been associated with HCC. This study aimed to determine the existence of specific IgG antibodies against F.

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Background: Fascioliasis is an infectious disease caused by parasites Fasciola hepatica and F. gigantica. Humans are infected by the consumption of vegetables and water contaminated with the infective form of the parasite.

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Fasciola hepatica is the causative agent of fasciolosis in Peru; the disease is an important public health problem by the high prevalence of the human infection affecting mainly children and a major veterinary problem by the high rates of infected livestock. The human disease is endemic in the Sierra and the Coast but sporadic in the Amazonia, and reported in 18 Departments, while the animal infection in 21 of 24 Departments of Peru. Transmission occurs in Andean rural populations engaged in agriculture, but recently an increasing number of people became infected in the cities.

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The aim of this study was to assess and apply a microsatellite multiplex system for parentage determination in alpacas. An approach for parentage testing based on 10 microsatellites was evaluated in a population of 329 unrelated alpacas from different geographical zones in Perú. All microsatellite markers, which amplified in two multiplex reactions, were highly polymorphic with a mean of 14.

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Polymorphism in SLC11A1 has been implicated in host susceptibility to tuberculosis. We have studied associations between INT4, D543N, and 3'UTR polymorphisms of SLC11A1 and different clinical forms of TB. Analysis used 507 patients with pulmonary TB, 123 with extra pulmonary TB and 513 controls.

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Fasciola hepatica has recently emerged as a major pathogen of humans from reports on areas of endemicity and hyper-endemicity for fascioliasis. This situation is aggravated by the lack of standard assays for the screen diagnosis of F. hepatica infection in humans living in endemic areas.

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Article Synopsis
  • 1alpha,25-dihydroxyvitamin D(3) (D(3)) enhances the maturation of myeloid cells and increases surface markers CD14 and CD11b, indicating cell differentiation.
  • The activation of phosphatidylinositol 3-kinase (PI 3-kinase) is crucial for D(3)-induced CD14 and CD11b expression, as evidenced by the inhibition of these effects using specific PI 3-kinase inhibitors and antisense oligonucleotides.
  • Unlike CD14 and CD11b, the expression of the Cdk inhibitor p21 is not affected by the inhibitors, suggesting that PI 3-kinase's role in D
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Mechanisms regulating lipopolysaccharide (LPS)-induced adherence to intercellular adhesion molecule (ICAM)-1 were examined using THP-1 cells transfected with CD14-cDNA (THP-1wt). THP-1wt adherence to ICAM-1 was LPS dose-related, time-dependent, and inhibited by antibodies to either CD14 or leukocyte function associated antigen (LFA)-1, but was independent of any change in the number of surface expressed LFA-1 molecules. A potential role for phosphatidylinositol (PI) 3-kinase (PI 3-kinase) in LPS-induced adherence was examined using the PI 3-kinase inhibitors LY294002 and Wortmannin.

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Early atherosclerotic lesions are characterized by the presence of cholesterol-rich, macrophage-derived foam cells. It has recently been shown that macrophage proliferation occurs during the development of early lesions and that oxidized low density lipoprotein (LDL) stimulates macrophage growth. Possible mechanisms for this induction of macrophage growth include potentiation of mitogenic signal transduction by a component of oxidized LDL following internalization and degradation, interaction with integral plasma membrane proteins coupled to signaling pathways, or direct or indirect activation of growth factor receptors on the cell surface (e.

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Lipoarabinomannan (LAM) is a putative virulence factor of Mycobacterium tuberculosis that inhibits monocyte functions, and this may involve antagonism of cell signaling pathways. The effects of LAM on protein tyrosine phosphorylation in cells of the human monocytic cell line THP-1 were examined. LAM promoted tyrosine dephosphorylation of multiple cell proteins and attenuated phorbol 12-myristate 13-acetate-induced activation of mitogen-activated protein kinase.

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Article Synopsis
  • The study investigated how PKC-zeta, a specific isoform of protein kinase C, is activated in human monocytes treated with bacterial lipopolysaccharide (LPS).
  • Analysis revealed that PKC-zeta is the main enzyme involved, as it was activated without needing lipids, calcium, or diacylglycerol, and showed consistent phosphorylation activity on certain peptides.
  • Additionally, the activation of PKC-zeta appears to rely on signaling from phosphatidylinositol 3-kinase (PI 3-kinase), as inhibitors of this pathway blocked its activation in monocytes.
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p53/56lyn and other src family tyrosine kinases become activated in monocytes treated with LPS. In a variety of systems, phosphatidylinositol 3-kinase (PI 3-kinase) is believed to be a downstream effector of tyrosine kinases, and activation of PI 3-kinase results in increased levels of D3-phosphorylated metabolites of phosphatidylinositol (PtdIns). To examine whether LPS activates PI 3-kinase, freshly isolated human, peripheral blood monocytes were labeled in vitro with [32P]orthophosphate, and inositol phospholipids were detected after extraction and separation of lipids by TLC.

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To investigate mechanisms of mononuclear phagocyte cell signaling, the effects of bacterial LPS on protein kinase activities in normal human peripheral blood monocytes were examined. Incubation of intact monocytes with LPS brought about time- and concentration-dependent increases in myelin basic protein (MBP) phosphotransferase activity in high speed supernatants of cell lysates. Anion-exchange chromatography on Mono Q demonstrated that LPS treatment resulted in two principal peaks of stimulated MBP kinase activity.

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