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Dive into the research topics where Juan G Maldonado-Estrada is active.

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Featured researches published by Juan G Maldonado-Estrada.


Clinical and Experimental Immunology | 2001

Placental cytokine and chemokine production in HIV-1-infected women: trophoblast cells show a different pattern compared to cells from HIV-negative women

M. Moussa; Pierre Roques; N. Fievet; E. Menu; Juan G Maldonado-Estrada; J. Brunerie; René Frydman; X. Fritel; F. Herve; Gérard Chaouat

In utero transmission of HIV‐1 has been demonstrated and may account for around 10–20% of all materno–fetal HIV‐1 transmission. The possible routes for such transmission are transannexial or transplacental. In both cases, the microenvironment (cytokines and chemokines) at the placental interface could be an important regulatory factor in viral transmission.


Animal Reproduction Science | 2000

Follicular dynamics during postpartum anestrus and the first estrous cycle in suckled or non-suckled Brahman (Bos indicus) cows

G. Henao; M. Olivera-Ángel; Juan G Maldonado-Estrada

Brahman (Bos indicus) cows, were selected at 28+/-10 days after calving and analyzed by real time rectal ultrasonography three times a week, in order to evaluate and compare follicular and corpus luteum development during postpartum (PP) anestrus and the first PP estrous cycle under sylvopastoril conditions. Suckling (S, n=11) or non-suckling (NS, n=5) cows were evaluated in a zone of tropical dry forest (450m of altitude, mean temperature=27 degrees C, annual rainfall=1000mm). Estrous detection was performed twice daily by direct observation. Progesterone was quantified using RIA. From 28+/-10 days postcalving to resumption of estrous cycles, there were no differences (P>0.05) between NS and S cows for diameter of the dominant or first subordinate follicle, follicular growth rate, or interdominance interval. Silent ovulation, corpus luteum formation and subsequent progesterone concentrations ranging from 0.3 to 9. 7ng/ml, were found in both groups. The first calving to ovulation and calving to standing estrus intervals were shorter (P<0.01) in NS (34.8+/-5.81 and 41.2+/-9.03 days) than in S (65+/-4.82 and 81+/-6. 21 days) cows. Follicular development and progesterone concentrations during the first PP estrous cycle did not differ (P>0. 05) between NS and S cows. These results suggest that Brahman cows could have an early PP resumption of follicular recruitment if fed under sylvopastoril system conditions. However, non-suckled cows did have an earlier standing estrus and ovulation than did suckled cows.


Journal of Cutaneous Pathology | 2010

Broad histopathologic patterns of non-glabrous skin and glabrous skin from patients with a new variant of endemic pemphigus foliaceus-part 1

Michael S. Howard; María Mercedes Yepes; Juan G Maldonado-Estrada; Edinson Villa‐Robles; Andrés Jaramillo; Jorge Botero; Pablo Javier Patiño; Takashi Hashimoto; Ana Maria Abreu-Velez

A prospective, controlled epidemiologic survey performed in El Bagre, Colombia revealed a new variant of endemic pemphigus disease, occurring in a gold mining region. The disease resembled Senear‐Usher syndrome, and occurred in an endemic fashion. The aim of this study is to describe the most frequent histopathologic patterns in non‐glabrous skin and in glabrous skin observed in these patients, and their clinical correlation. The study was performed on non‐glabrous skin biopsies of 30 patients from the dominantly clinical affected areas (either on the chest, arms or face). Simultaneously, biopsies from the palms were obtained in 10 randomly chosen patients of the 30 total patients. The specimens were examined following hematoxylin and eosin (H&E) staining. The most common blisters observed were subcorneal, although in some cases intraspinous and subepidermal blisters were visualized. Our results showed a very heterogeneous pattern of histopathologic patterns in non‐glabrous skin, which seemed to correlate with the clinical features. The most common pattern was typical pemphigus foliaceus‐like, with some lupus erythematosus‐like features. A non‐specific, chronic dermatitis pattern prevailed in the clinically controlled patients taking daily corticosteroids. In the patients who have had the most severe and relapsing pemphigus, early sclerodermatous changes and scleredermoid alterations prevailed in their reticular dermis. In addition to the scleredermoid alterations, the reticular dermis showed a paucity of appendageal structures. On the contrary, in the palms, a similar pattern was seen in all cases, including thickening of the stratum corneum, hypergranulosis, edema in the papillary and reticular dermis and a dermal perivascular lymphocytic infiltrate. The direct immunofluorescence of the glabrous vs. the non‐glabrous skin also showed some differences. We conclude that the histopathologic features of this new variant of endemic pemphigus are complex, therefore, classical histopathologic features previously described for superficial, endemic pemphigus cannot be used alone to diagnose this disease.


Journal of Reproductive Immunology | 2013

Cytokine production by non-stimulated peripheral blood NK cells and lymphocytes in early-onset severe pre-eclampsia without HELLP

J.C. Bueno-Sánchez; B. Agudelo-Jaramillo; L.F. Escobar-Aguilerae; A. Lopera; A.P. Cadavid-Jaramillo; Gérard Chaouat; Juan G Maldonado-Estrada

Preeclampsia involves an exacerbated maternal inflammatory response that suggests a possible role of innate immunity. NK cells can promote this kind of response through cytokine production and the expression of activating or inhibitory receptors. The aims of the present study were to explore cytokine production by peripheral blood mononuclear cells, as well as cytotoxic ability and receptor expression for HLA-E and HLA-G molecules in peripheral natural killer (NK) cells of women with early-onset severe preeclampsia without HELLP (hemolysis, elevated liver enzyme levels and a low platelet count) syndrome. The expression of the ILT2, KIRDL4, NKG2A, and NKG2C receptors and of cytotoxic activity was measured in non-stimulated NK cells, whereas the intracellular expression of IL-4, IL-10, IL-13, IL-12, IFNγ, TNF and VEGF, was assessed in non-stimulated peripheral blood mononuclear cells subsets using flow cytometry. Circulating soluble HLA-G was also determined by ELISA. The intracellular cytokines tested were significantly higher in NK cell subsets from severely preeclamptic women compared with the control group. On the other hand, the percentage of NK cells expressing NKG2A or NKG2C and the cytotoxic activity of NK cells were significantly higher in severely preeclamptic women. Furthermore, there was a significant correlation between urine protein concentration and soluble human leukocyte antigen G (soluble HLA-G) in serum. We conclude that patients with early-onset severe preeclampsia without HELLP syndrome have increased NK cell function related to cytokine production, cytotoxicity and expression of lectin-like receptors such as NKG2.


American Journal of Reproductive Immunology | 2003

Predominant Intracellular Expression of CXCR4 and CCR5 in Purified Primary Trophoblast Cells from First Trimester and Term Human Placentae

Juan G Maldonado-Estrada; Elisabeth Menu; Pierre Roques; Bruno Vaslin; Alice Dautry-Varsat; Françoise Barré-Sinoussi; Gérard Chaouat

Problem: The aim of the present study was to define the expression of CXCR4 and CCR5 on non‐cultured non‐stimulated primary human trophoblast cells (TCs) immediately after their immunopurification.


Journal of Reproductive Immunology | 2014

Sera from early-onset, severely preeclamptic women directly modulate HLA-E expression in the EA.hy296 endothelial cell line.

J.C. Bueno-Sánchez; S. Peña-Alzate; R.B. Peña; B. Agudelo-Jaramillo; A.P. Cadavid-Jaramillo; Gérard Chaouat; Juan G Maldonado-Estrada

The expression of endothelial HLA-E in the context of the systemic inflammatory response observed in preeclampsia has not been established. An experimental study was designed to determine the effect of the sera of pregnant women on the expression of HLA-E in EA.hy296 endothelial cells. First, measurements of protein fractions were performed in sera from early-onset, severely preeclamptic women without HELLP syndrome, in which there was no significant difference in total proteins between the groups, but a reduced level of plasma albumin and an increase in α1-globulin were observed in both groups of pregnant women compared with non-pregnant women. Measurements of colloid osmotic pressure (COP) using a recalculated albumin/globulin ratio formula determined only a significant decrease in COP in all pregnant groups compared with non-pregnant women. The expression of membrane HLA-E was increased in EA.hy296 endothelial cells stimulated with sera of early-onset, severely preeclamptic women, while recombinant interferon-γ (IFN-γ) significantly reduced the expression of membrane HLA-E. Pro-inflammatory cytokines were measured by Luminex in the serum samples, and increased levels of tumor necrosis factor (TNF) and decreased levels of IFN-γ were observed in early-onset, severe preeclampsia compared with normal pregnancy. Moreover, soluble HLA-E was detected in these serum samples by Western blot and ELISA, but no significant difference was found. This raises the possibility that a systemic inflammatory response promotes a compensatory mechanism of COP balance in severe preeclampsia by release of inflammation-induced factors, including endothelial HLA-E. Evidence is now provided regarding HLA-E expression by EA.hy296 cells.


Journal of Veterinary Science | 2017

Histopathologic findings in uterus and ovaries collected from clinically healthy dogs at elective ovariohysterectomy: a cross-sectional Study.

Daniel Maya-Pulgarin; María S González-Domínguez; Diego Aranzazu-Taborda; Natalia Mendoza; Juan G Maldonado-Estrada

Opinions on ovariohysterectomy (OHE) of bitches vary depending on region and country. In this descriptive, prospective cross-sectional study, uterine tracts and ovaries exhibiting gross pathologic findings (n = 76) were collected post-surgery from a reference population of 3,600 bitches (2.11% incidence) that underwent elective OHE during September to November 2013 and evaluated by histopathology examination. Data were evaluated by using descriptive statistics and chi-squared tests. Bitches were of crossbred background with average age 5 years (range 0.6–8.0 years) and most were nulliparous (69.7%) with no anamnesis of reproductive diseases (81.6%). Frequencies of proestrus, estrus, and diestrus were 42.1%, 6.6%, and 19.7%, respectively. The presence of mammary gland masses (5.3%) significantly correlated with histopathologic findings in ovaries and age of the bitch (p < 0.05). Predominant uterine histopathologies included cystic endometrial hyperplasia, periglandular fibrosis, lymphoplasmocytary endometritis, and adenomyosis (19.7%, 14.5%, 4.0%, and 2.6%, respectively). In ovaries, hyperplasia of rete ovarii, follicular cysts, oophoritis, adenoma of the rete ovarii, cysts of superficial structures, and granulosa cell tumors (10.5%, 10.5%, 7.9%, 4.0%, 2.6%, and 2.6%, respectively) were observed. The results reveal the presence of subclinical pathologies in healthy bitches, suggesting that OHE at an early age is beneficial for prevention of reproductive pathologies.


The Journal of Clinical Endocrinology and Metabolism | 2002

Transcriptional Expression of Genes Involved in Cell Invasion and Migration by Normal and Tumoral Trophoblast Cells

Jean-Louis Janneau; Juan G Maldonado-Estrada; Gérard Tachdjian; Isabelle Miran; Nelly Motté; Patrick Saulnier; Jean-Christophe Sabourin; Jean-François Coté; Bénédicte Simon; René Frydman; Gérard Chaouat; Dominique Bellet


Journal of Immunological Methods | 2004

Evaluation of Cytokeratin 7 as an accurate intracellular marker with which to assess the purity of human placental villous trophoblast cells by flow cytometry.

Juan G Maldonado-Estrada; Elisabeth Menu; Pierre Roques; Françoise Barré-Sinoussi; Gérard Chaouat


Revista Colombiana De Ciencias Pecuarias | 2007

Relación entre el recuento de células somáticas individual o en tanque de leche y la prueba CMT en dos fincas lecheras del departamento de Antioquia (Colombia)

Mario F Cerón-Muñoz; Edwin J Agudelo; Juan G Maldonado-Estrada

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A. Lopera

University of Antioquia

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B. Agudelo

University of Antioquia

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