Cadáveres quemados. Estudio antropológicoforense / Burned corpses. Forensic anthropological study

La acción del fuego sobre el cuerpo puede producirafectación de la piel determinando quemaduras de diversosgrados o carbonización llegando a afectar al hueso, eincluso a calcinarlo. Cuando el grado de afectación esintenso deben aplicarse los protocolos de antropologíaforense, teniendo en cuenta las particularidades del caso.Presentamos cuatro casos estudiados en el Laboratoriode Antropología Forense de la Escuela de Medicina Legalde Madrid, en los que se han seguido técnicas diferentesa fin de poder establecer la identificación del cadáver y eldiagnóstico de la muerte así como otras cuestiones deinterés en la investigación antropológico forense(AU)

The action of fire on the body can affect the skindetermining diverse degree of burns or may affect thebone, even cremate it. When the degree of burn isintense, protocols of forensic anthropology should be used,taking into account the details of each case. We presentfour cases studied in the Laboratory of ForensicAnthropology at the School of Legal Medicine in Madrid, inwhich different techniques have been used in order toestablish the identification of the cadaver and the cause ofdeath as well as other questions of interest in the forensicanthropological investigation(AU)

Expression of functional chemokine receptors CXCR3 and CXCR4 on human melanoma cells.

Chemokines are secreted into the tumor microenvironment by tumor-infiltrating inflammatory cells as well as by tumor cells. Chemokine receptors mediate agonist-dependent cell responses, including migration and activation of several signaling pathways. In the present study we show that several human melanoma cell lines and melanoma cells on macroscopically infiltrated lymph nodes express the chemokine receptors CXCR3 and CXCR4. Using the highly invasive melanoma cell line BLM, we demonstrate that the chemokine Mig, a ligand for CXCR3, activates the small GTPases RhoA and Rac1, induces a reorganization of the actin cytoskeleton, and triggers cell chemotaxis and modulation of integrin VLA-5- and VLA-4-dependent cell adhesion to fibronectin. Furthermore, the chemokine SDF-1alpha, the ligand of CXCR4, triggered modulation of beta(1) integrin-dependent melanoma cell adhesion to fibronectin. Additionally, Mig and SDF-1alpha activated MAPKs p44/42 and p38 on melanoma cells. Expression of functional CXCR3 and CXCR4 receptors on melanoma cells indicates that they might contribute to cell motility during invasion as well as to regulation of cell proliferation and survival.

Associations between TGF-beta1 receptors in human bone marrow stromal cells.

Bone marrow stromal cells are required for sustained haemopoiesis. Transforming growth factor-beta (TGF-beta) is a multifunctional cytokine present in the bone marrow microenvironment which regulates the expression of several cytokines, cytokine receptors and cell adhesion elements. The TGF-beta receptors type I and II, and endoglin, mediate TGF-beta1 binding to the membrane of human bone marrow stromal cells. [125I]TGF-beta1-affinity labelling experiments showed that three different anti-endoglin monoclonal antibodies co-immunoprecipitated a 68 kD TGF-beta1-labelled polypeptide together with TGF-beta1/endoglin complexes. Here, we have shown that the 68 kD receptor corresponds to the type I receptor, indicating that endoglin and the type I receptor associate on the membrane of these cells upon ligand binding. The expression of endoglin by stromal cells was found to be up-regulated by TGF-beta1, but not by IL-1beta. The association of endoglin with signalling components of the TGF-beta receptor system on the membrane of bone marrow stromal cells might modulate TGF-beta1 access to the signalling pathways, and therefore it could regulate TGF-beta1-mediated stromal cellular responses.

Differential use of very late antigen-4 and -5 integrins by hematopoietic precursors and myeloma cells to adhere to transforming growth factor-beta1-treated bone marrow stroma.

The very late antigen (VLA)-4 and VLA-5 integrins mediate hematopoietic progenitor cell attachment to bone marrow (BM) stroma. Transforming growth factor-beta1 (TGF-beta1) is a cytokine present in the BM microenvironment that has been shown to regulate the synthesis of adhesion elements in several cell types. We have investigated whether TGF-beta1 action on human BM stromal cells affected the adhesion of progenitor cells involving integrins VLA-4 and VLA-5. Two precursor cell lines, pre-B Nalm-6 and the multipotential UT-7, attached to untreated primary stroma and to the human BM stromal cell line Str-5 preferentially using VLA-4. However, treatment of the stroma with TGF-beta1 resulted in a significant reduction in the participation of VLA-4 in mediating precursor cell adhesion to stroma and a concomitant increase in the utilization of VLA-5. This effect was not exclusive of normal BM stroma. Treatment with TGF-beta1 of stroma from multiple myeloma BM samples produced a substantial increase in VLA-5 use by the myeloma cell line NCI-H929 to adhere to this stroma. The differential use of VLA-4 and VLA-5 correlated with an increase in fibronectin surface expression by stromal cells in response to TGF-beta1. Adhesion assays to purified fibronectin using Nalm-6 cells showed a predominant utilization of VLA-4 at low concentrations of this ligand, whereas higher concentrations resulted in a preferential use of VLA-5. These results indicate that regulation of fibronectin expression on BM stromal cells by TGF-beta1 results in a modulation of the pattern of integrins used by the precursor and myeloma cells to adhere to BM stroma, which could have important consequences on the proliferation and differentiation of hematopoietic precursor cells as well as on the localization and growth of myeloma cells.

TGF-beta1-binding proteins on human bone marrow stromal cells.

The stromal cells are integral components of the bone marrow (BM) that provide and respond to cytokines, and offer adhesion elements for hematopoietic cell homing. Steady-state hematopoiesis results from a balance between negative and positive acting cytokines, whose expression is in addition the subject of regulation. TGF-beta1 is present in the BM microenvironment and plays a central role in controlling hematopoiesis, by modulating the synthesis of cytokines and cytokine receptors, as well as cell adhesion molecules. We have recently described the TGF-beta1 receptor system expressed on human BM stromal cells. The consequences of signalling through this system, which can affect stromal cell function, and hence, influence the hematopoiesis, is the subject of this review.

Characterization of TGF-beta 1-binding proteins in human bone marrow stromal cells.

The proliferation and differentiation of haemopoietic progenitor cells is dependent on their close relation with bone marrow stromal cells, which constitute a source of cytokines as well as expressing receptors for both the cytokines and progenitor cell adhesion molecules necessary for regulated haemopoiesis. We have generated human bone marrow stromal cell cultures and analysed the TGF-beta 1 receptor components expressed by these cells. [125I]TGF-beta 1-affinity labelling experiments showed the involvement of type I and II receptors in the binding of TGF-beta 1, as demonstrated by specific immunoprecipitation of [125I]TGF-beta 1-receptor complexes. In addition, large TGF-beta 1-labelled complexes displaying an electrophoretic mobility similar to betaglycan were also observed in these experiments. Endoglin, another component of the TGF-beta receptor system, was detected by flow cytometry on the surface of cultured marrow stromal cells, and in the human bone marrow stromal cell line Str-5, and was immunoprecipitated from surface-iodinated cells. Endoglin on the stromal cells was able to bind TGF-beta 1, as demonstrated by specific immunoprecipitation of [125I]TGF-beta 1-endoglin complexes using anti-endoglin antibodies. The results presented provide evidence that bone marrow stromal cells are fully capable of responding to TGF-beta 1. Given the important role of TGF-beta as a regulator of the synthesis of cytokines and cytokine receptors, as well as cell adhesion molecules, these data indicate that the binding of TGF-beta 1 by stromal cells might represent an important step in the regulation of the proliferation and differentiation of haemopoietic progenitor cells.

Human lymphocytotoxic monoclonal autoantibodies from a highly sensitized renal dialysis patient.

A panel of 5 human monoclonal autolymphocytotoxic antibodies (IRM-3, IRM-4, IRM-7, IRM-8, and IRM-10) of the IgM class was established from a highly sensitized renal dialysis patient (IRM), by the generation of mouse-human heterohybridomas. This panel was screened for reactivity against foreign and autoantigens by ELISA, and for reactivity against different tissue sections and HEp-2 slide preparations by indirect immunofluorescence. Cytotoxicity screening of heterohybridoma supernatants gave broad panel reactivity profiles, being cytotoxic against B cells from patient IRM and also against most B cells tested and less reactive with chronic lymphocytic leukemia B cells; T cells were the least sensitive target. Immunoblotting showed that monoclonal IRM displayed some heterogeneity in their binding profiles, although all of them recognized a cellular structure of 26 kDa. None of the heterohybridoma cell lines exhibited cytoplasmic nor surface staining with an anti-CD5 mAb. Results obtained showed that all the autolymphocytotoxic mAbs generated were also able to react against certain nuclear and cytoplasmic self-structures as well as foreign compounds. Monoclonal antibody IRM-7 and, to a lesser degree, IRM-10 exhibited multispecific properties similar to those observed for polyreactive or natural antibodies.

Application of cellular ELISA (CELISA) to the detection of human monoclonal autoantibodies.

This work describes the application of cellular enzyme-linked immunosorbent assay (CELISA) for the detection of both polyreactive and monospecific human monoclonal antibodies against autoantigens. The CELISA is ideally suited for the screening of a large number of hybridoma culture supernatants, being, in this way, superior to other methods commonly used for the detection of autoantibody activity, such as indirect immunofluorescence on tissue sections and slide cell preparations, in terms of speed and sensitivity. This assay demonstrated higher sensitivity than ELISA using autoantigenic extracts from rabbit thymus, human spleen, nucleoprotamine, and salmon sperm nuclei, and enzyme immunoassays using ssDNA, dsDNA, and affinity purified autoantigens as substrate. The CELISA has been also successfully applied to the detection of autolymphocytotoxic antibody activity in heterohybridoma supernatants.

Application of the MAILA technique to the study of human anti-HLA monoclonal antibody specificity.

The monoclonal antibody-specific immobilization of lymphocyte antigens (MAILA) assay was developed to detect antibodies present in human alloantisera against antigens of different major histocompatibility complex loci, particularly of class II specificity. The MAILA assay has been used in our laboratory to the determination of the type of HLA molecule recognized by human monoclonal antibodies 91C2 (anti-A2 + 28), 34F11 (anti-DQ1), and 2A2 (anti-DQ1 + 4 + short DQ7), using well characterized monomorphic as well as polymorphic murine monoclonals for the specific immobilization of HLA molecules. Results obtained show that the MAILA assay is also a valuable tool for the determination of specific human MHC locus products recognized by human monoclonal antibodies.

Cloning of human heterohybridoma cell lines using chronic lymphocytic leukemia B cells as a feeder layer.

B cells from the peripheral blood of chronic lymphocytic leukemia patients were isolated by gradient density centrifugation and used without irradiation as a feeder layer in the cloning of human heterohybridoma cell lines by limiting dilution. Cloning efficiencies were high with all the cell lines tested. These feeder leukemia B cells could also be successfully used after having been stored in liquid nitrogen.

Significacion patogenica de Candida en pacientes con vaginitis. / Pathogenic significance of Candida in papatients with vaginitis

Se tomaron 500 muestras de exudado vaginal en mujeres que asistian por primera vez a consulta gineco-obstetrica. En 229 pacientes se aislo Candida, de las cuales 134 (26.8 por ciento) correspondian a flora normal y 95 (19.0 por ciento) a candidosis enfermedad. Los sintomas mas frecuentes fueron leucorrea, eritema y prurito; el embarazo fue el factor de oportunismo mas frecuente, seguido por la desnutricion y anemia. En la clase socio-economica media se encontro la mayor frecuencia de candidosis vaginal, en relacion a las clases alta y baja. Las especies mas frecuentes fueron C. albicans (69.9 por ciento), C.tropicalis (20 por ciento) y C. stellatoides (5.2 por ciento)