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R Hernández Pando

Publications and source records attributed to R Hernández Pando.

8 recordsLinked to original sources
PubMed2003

Expression of cyclooxygenase type 2 in lepromatous and tuberculoid leprosy lesions.

BACKGROUND: Leprosy is an infectious disease with two polar forms, tuberculoid leprosy (TL) and lepromatous leprosy (LL), which are dominated by T-helper (Th) 1 and Th2 cells, respectively. High concentrations of prostaglandin E2 produced by the inducible enzyme cyclooxygenase type 2 (COX-2) in LL could inhibit Th1 cytokine production, contributing to T-cell anergy. OBJECTIVES: To compare the COX-2 expression in LL and TL. METHODS: Skin biopsies from 40 leprosy patients (LL, n = 20; TL, n = 20) were used to determine by immunohistochemistry and automated morphometry the percentage of COX-2 immunostained cells. RESULTS: Most COX-2-positive cells were macrophages; their percentages in the inflammatory infiltrate located in the papillary dermis, reticular dermis and periadnexally were significantly higher in LL than TL (P < 0.001 by Student's t-test). CONCLUSIONS: The high expression of COX-2 in LL may be related to high prostaglandin production contributing to T-cell anergy.

Biopsy↗
PubMed2002

Immunological and pathological comparative analysis between experimental latent tuberculous infection and progressive pulmonary tuberculosis.

Mycobacterium tuberculosis produces latent infection or progressive disease. Indeed, latent infection is more common since it occurs in one-third of the world's population. We showed previously, using human material with latent tuberculosis, that mycobacterial DNA can be detected by in situ PCR in a variety of cell types in histologically-normal lung. We therefore sought to establish an experimental model in which this phenomenon could be studied in detail. We report here the establishment of such a model in C57Bl/6 x DBA/2 F1 hybrid mice by the intratracheal injection of low numbers of virulent mycobacteria (4000). Latent infection was characterized by low and stable bacillary counts without death of animals. Histological and immunological study showed granulomas and small patches of alveolitis, with high expression of tumour necrosis factor alpha (TNFalpha), inducible nitiric oxide synthase (iNOS), interleukin 2 (IL-2) and interferon gamma (IFNgamma). In contrast, the intratracheal instillation of high numbers of bacteria (1 x 106) produced progressive disease. These animals started to die after 2 months of infection, with very high bacillary loads, massive pneumonia, falling expression of TNF-alpha and iNOS, and a mixed Th1/Th2 cytokine pattern. In situ PCR to detect mycobacterial DNA revealed that the most common positive cells in latently-infected mice were alveolar and interstitial macrophages located in tuberculous lesions, but, as in latently-infected human lung, positive signals were also seen in bronchial epithelium, endothelial cells and fibroblasts from histologically-normal areas. Our results suggest that latent tuberculosis is induced and maintained by a type 1 cytokine pattern plus TNFalpha, and that mycobacteria persist intracellularly in lung tissue with and without histological evidence of a local immune response.

Animals↗
PubMedDate not supplied

[Chemokines, a new family of cytokines in inflammatory cell recruitment].

Cell recruitment is a crucial event in the establishment of both acute and chronic inflammatory responses, including acute and delayed type hypersensitivity reactions. Among other significant factors like adhesion molecules, chemokines and its receptors are crucial elements that lead leukocyte migration to the tissues. Chemokines are a large group of peptidic cytokines which have a conserved motif of 4 cisteins. These cistein residues form pairs which permit to classify them in two groups, the alpha and beta subfamilies. In general terms, alpha subfamily has preferential chemotactic activity on granulocytes, and beta subfamily attracts mainly lymphocytes and macrophages. Besides their chemotactic activity, chemokines also participate in some other important biological processes like hematopoiesis, angiogenesis, and anti-tumoral activity. Chemokines also play an important role in certain pathological conditions, for instance in some allergic processes they have an essential role in the pathogenesis. In autoimmune and infectious diseases, this cytokine family is also important as is suggested by the presence of chemokine receptors in rheumatoid arthritis inflammed synovia or the HIV receptor activity that chemokine receptors display which apparently play a significant role in the natural resistance against this infectious agent. Preferential leukocyte recruitment mediated by chemokines is a potential target for pharmacological modulation, which in turn may lead to a novel and efficient types of therapeutic control of inflammatory diseases with diverse etiology.

Animals↗
PubMedDate not supplied

[Nephropathy in a case of Fabry's disease].

The present communication describes a 22 year-old male with clinical, biochemical and histopathological signs of Fabry's disease (FD). This is the second case of FD reported in Mexico. The main clinical manifestations of this patient were during puberty: intermittent weakness, acroparesthesias and hypohidrosis. At age 21 he developed heavy proteinuria (7-12 g/day) systemic hypertension and moderate renal failure. The kidney biopsy showed the typical alterations described in FD. On light microscopy, the renal pathology showed numerous vacuolated epithelial cells in the glomerular wall, giving them a "foamy" appearance; vacuolization was due to the presence of lipid material within these cells and in the interstitium. In electron microscopy, dense, irregularly shaped osmiophilic, laminated bodies with myelinlike configuration, were seen within the glomerular epithelial cells and in the urinary spaces. The low alfa-galactosidase activity in serum (0.18 nmol/h/mL normal values: 12.8) confirmed the diagnosis. Our findings in this case indicate that patients with FD may start with renal symptoms alone, which were full blown nephrotic syndrome, hypertension and moderate renal failure.

Adult↗
PubMedDate not supplied

[Multiple familial polyposis. Report of 4 cases and association with mucinous adenocarcinoma of the colon].

Four cases of familial polyposis coli (FPC), seen at Dr. Manuel Gea González General Hospital from 1985 to 1987, are presented. Three females and one male, with ages ranging between 23 and 52 years, are presented. The clinical picture included bloody feces, polyp prolapse, and a maxillary osteoma. In 3 cases the correct preoperative diagnosis was made by rectosigmoidoscopy, biopsy and barium enema. In one patient, urgently operated on, the diagnosis was postoperatively made by colonoscopy. The adenocarcinoma of the colon appeared associated with FPC in three cases (one of the mucinous variety). One total coloproctectomy and two abdominal colectomies with ileorectal anastomosis were performed. One patient operated on because of bowel obstruction was treated by right hemicolectomy. This case developed abdominal carcinomatosis afterwards. One woman died; another one was lost during follow-up, and the other one had no complications. The association of FPC and mucinous adenocarcinoma of the colon is reported for the first time.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

[Takayasu's arteritis. A seroimmunological test of its relationship to mycobacterial infection].

Takayasu's arteritis is an inflammatory arteritis of unknown origin. It affects the aorta, its main branches and at times the pulmonary artery. Takayasu's arteritis is a worldwide disease, however, there is predilection to affect young women of mongoloid ancestry, therefore most cases do occur in the Far East and Latin America. For more than 50 years a relationship with mycobacterial infection has been sought without definite proof. In this investigation we found a circulating IgG antibody in the sera of Takayasu's arteritis patients, which recognizes a 38 kD glycoprotein of M. tuberculosis. This glycoprotein is an specific antigen in the human immune response against mycobacterial infection.

Adult↗