Browsing by Autor "Silvana Vielma"

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Cambios dinámicos de citoquinas proinflamatorias, moléculas de adhesión y marcadores de activación linfocítica como indicadores tempranos de severidad en pacientes con Dengue
(Universidad Internacional de La Rioja, 2014) Silvana Vielma; María Odreman Macchioli; Saberio Pérez; Noraida Mosqueda; Guillermo Comach; Eduardo Gallardo Téllez; José Mendoza
Varios mecanismos inmuno-patogénicos se han propuesto para explicar el incremento masivo de la permeabilidad vascularobservada en las formas severas de la infección por el Virus del Dengue (DENV). El objetivo del estudio fue determinar loscambios cinéticos de mediadores inflamatorios (IL-8, TNF-α), marcadores soluble de activación linfocítica temprana (sIL-2R,sTNF-Rp75) y fracciones solubles de moléculas de adhesión celular (sICAM-1, sVCAM-1) como marcadores tempranos deseveridad en pacientes con dengue. Veinte pacientes clasificados como Dengue (Dengue±Signos de Alarma,D±WS) y treintapacientes con Dengue Severo (DS) fueron incluidos en el estudio. Suero de individuos aparentemente saludables fueronincluidos como controles. En comparación con los individuos controles, los casos con Dengue mostraron niveles de IL-8 yTNF con diferencias no significativas en la fase febril o crítica de la enfermedad; sin embargo, un incremento significativo desICAM-1 y sVCAM-1 ocurrió en ambas fases, mientras que los niveles de sIL2R y sTNF-p75 se elevaron significativamentesolo en la fase crítica de la enfermedad. En comparación con los casos con dengue y controles, los pacientes con DS mostraron diferencias significativas en los niveles de IL-8 y TNF-α durante la fase crítica y un incremento significativo demoléculas de adhesión en ambas fases, pero los niveles más elevados de sVCAM-1 y sIL-2R fueron observados en la fasefebril. En conclusión, sIL-2R y sVCAM-1, como marcadores tempranos de activación linfocítica y endotelial, servirían comoindicadores de severidad en la fase aguda de la infección por el virus del dengue.Dinamic changes of pro-inflammatory cytokines, adhesion molecules and lymphocytesactivation markers as early indicators of diseases severity in patients with DengueAbstractSeveral immunopathogenic mechanisms have been proposed to explain the massive increase of vascular permeabilityobserved in the severe forms of infection by Dengue Virus (DENV). Our aim was to determine the kinetic changes ofinflammatory mediators (IL-8, TNF- α), soluble early lymphocyte activation markers (sIL-2R, sTNF-Rp75) and solublefractions of cell adhesion molecules (sICAM-1 and sVCAM-1) as indicators for early recognition of disease severity inpatients with laboratory-confirmed dengue. Twenty patients classified as Dengue±Warning Signs (D±WS) and thirty patientswith Severe Dengue (SD) were included in the study. Serums of apparently healthy individuals were included as controls.Compared with normal subjects, D±WS cases did not show significant differences in the levels of IL-8 or TNF-α during theacute nor in the critical stages of the disease; however, in D±WS cases levels of sICAM-1 and sVCAM-1 were higher thancontrols during both phases; in contrast, significant increase of sTNF-p75 and sIL2R levels were observed during the criticalphase of the disease. Compared with both dengue patients and controls, patients with SD showed significant rise in thelevels of IL-8 and TNF-α during the critical phase of the disease and a significant increase in adhesion molecules weredetected in both phases, but the highest levels of sVCAM-1 and sIL-2R were observed only during the acute stage of thedisease. In conclusion, sIL-2R and sVCAM-1, as early markers of lymphocyte and endothelial activation, would serves asindicators of severity during the acute phase of dengue infection.
Epidemiological and clinical characteristics of patients with malaria admitted to a hospital in Mérida, Venezuela
(Oxford University Press, 2019) Juan Carlos Gabaldón-Figueira; Siham Salmen; Nubia Silva; Betania Mancilla; Silvana Vielma
Twenty-two patients were from the Zulia state and eleven were from the Mérida state, mainly from the lowlands south of Lake Maracaibo. Six of these patients traveled to the Bolívar state between 2017 and 2019. Thirteen patients presented with the WHO criteria for severe malaria.Conclusions:Domestic migration to the southeast of Venezuela may have played an important role in the expansion of malaria in previously existing endemic areas of transmission and also in the increase in the number of cases of severe malaria.
Inflammatory mediators in patients with Dengue infection: role in early endothelial damage
(Universidad Internacional de La Rioja, 2013) Silvana Vielma
Several mechanisms have been proposed to explain the pathogenesis of dengue virus (DENV) infection. One of the most important finding is the production of pro-inflammatory cytokines as responsible of endothelial cells activation, plasma leakage and subsequently, disease severity. Methods: Our aim was to determined levels of inflammatory mediators (IL-8, TNF-α), soluble cell adhesion molecules (sICAM-1 and sVCAM-1) and soluble lymphocyte activation markers (sIL-2Rα, sTNF-RII/p75) during the course of DENV infection. Serum samples from fifty-two patients with confirmed DENV infection were collected during the acute (0-3 days after fever onset) and critical/recovery (4-7 days after onset) phases of the diseases. As controls, sera from non-febrile individuals were included. Patients were classified as dengue without warning signs (DwoWS), dengue with warning signs (DwWS) and severe dengue (SD).
Lepra lepromatosa . A propósito de un caso clínico
(Universidad Internacional de La Rioja, 2014) Anays Toro; Silvana Vielma; Pierina Petrosino Tepedino; Melisse Milano Molina
A case reportAbstract Leprosy is a chronic infectious disease, declared by the WHO as successfully controlled since several years ago, is causal by an acid-alcohol-resistant bacilli (AARB) called Mycobacterium leprae. Infection has a long incubation period and mainly affects skin, mucous membranes and peripheral nerves. Its clinical presentation comprises two polar types, lepromatous leprosy (LL), tuberculoid leprosy (TL) and three borderline expressions. Here we report a case of a 36 year-old male patient, who suffers since two years ago skin lesions characterized by hyperchromic macules that progressed to nodules, initially in hands and feet, then spread throughout the body, without respect of palm of hands and feet. Preceded by Dengue infection (20 days before), and a histopathological diagnosis as Glomangiosarcoma. Upon admission, the patient had countless indurated, multiform and confluent nodular lesions, associated to unaltered superficial or deep sensitivity or neuromuscular symptoms. Radiological studies from thorax, abdomen and pelvis showed no musculoskeletal or visceral lesions without nodal involvement. The second biopsy reported chronic inflammation, few lymphocytic infiltrate, foamy macrophages, countless and slightly curved intracellular (macrophages) AARB. Lepromin test was negative reported. The final diagnosis was lepromatous leprosy. Triple multitherapy (dapsone, rifampicin, clofazimine) was prescribed and two months later, evidence of improvement in the number and size of lesions was observed. Early diagnoses through clinical, histopathological, immunological tests are central to the broader context of clinical presentations in Leprosy.
Skewing of immune cell cytokine production by mediators from adipocytes and endothelial cells
(Taylor & Francis, 2014) Silvana Vielma; Richard L. Klein; Corinne A. Levingston; Matthew R. Young
Since adipose tissue is composed of adipocytes as well as other cell types including endothelial cells, this study sought to determine how mediators from adipocytes and from endothelial cells impact on immune cell production of cytokines. A minimalistic design was used in which media conditioned by adipocytes or by endothelial cells were added individually or as a mixture to normal spleen cells. Media from adipocytes or endothelial cells each stimulated spleen cell production of Th1 cytokines, Th2 cytokines, most of the measured inflammatory cytokines, and some chemokines. However, a mixture of media conditioned by adipocytes and by endothelial cells inhibited production of Th1 cytokines and skewed reactivity toward a Th2 and inflammatory phenotype. Adiponectin, but not leptin, was shown to contribute to the skewing of immune responsiveness to endothelial cell-derived mediators.