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1.
Int J Paleopathol ; 2(4): 231-235, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29539370

RESUMEN

Clinical reports for Eleonora of Toledo (1522-1562), the wife of Cosimo I de' Medici, imply that during her 28th year she developed pulmonary tuberculosis, which was complicated by an attack of pernicious malaria, killing her at age 40. Eleonora's autopsy indicated that she had severe lung lesions consistent with chronic pulmonary infection. To clarify her disease status, we performed paleomolecular investigations. Our results identified ancient DNA from the Mycobacterium tuberculosis complex (MTB), along with Leishmania infantum (VL). Our data are of particular interest since in Tuscany the endemic foci of L. infantum are widely distributed and overlapped with those of malaria prior to its eradication. Although we can only speculate about Eleonora's true state of health, this clear evidence of long-term co-infection with MTB and VL is of major medical and biological interest since the co-evolution of the two pathogens and host-pathogen interactions in co-infected individuals are still not fully understood.

2.
Eur Spine J ; 11(4): 308-20, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12193991

RESUMEN

During the process of degeneration, the intervertebral disc (IVD) shows a progressive and significant reduction in height due to tissue resorption. Intradiscal clefts and tears are major hallmarks of disc degeneration. Matrix-degrading enzymes such as matrix metalloproteinases (MMPs) are assumed to play a pivotal role in disc tissue degradation and resorption. The objective of this study was therefore to investigate the potential role of MMPs in extracellular matrix degradation leading to disc degeneration. This study was conducted on 30 formalin-fixed and EDTA-decalcified complete cross-sections of lumbar IVDs from cadavers of individuals aged between 0 and 86 years. Tissue sections were used for the immunolocalization of MMPs-1, -2, -3 and -9. The number of labeled cells was assessed by morphometric analyses, and was statistically correlated with the formation of clefts and tears, cellular proliferation, granular matrix changes and mucous degeneration. Furthermore, 30 disc specimens obtained during spinal surgery were used for in situ hybridization of MMP-2 and -3-mRNA. In addition, the enzymatic gelatinolytic activity was determined by in situ zymography in autopsy material. Immunohistochemistry showed the intradiscal expression of all four MMPs, which was confirmed by in situ hybridization, providing clear evidence for the synthesis of the enzymes within nucleus pulposus and annulus fibrosus cells. Gelatinolytic enzymatic activity was verified by in situ zymography. IVDs from infants and young adolescents remained almost completely unlabeled for all MMPs tested, while more MMPs-1 and -3 were seen in disc cells of younger adults than in those of a more advanced age; MMP-2 remained unchanged over the adult age periods, and MMP-9 was expressed in only relatively few cells. This pattern significantly correlated with the occurrence of clefts and tears. This correlation was strongest for MMP-1 ( P<0.0001), MMP-2 ( P<0.0017) and MMP-3 ( P<0.0005) in the nucleus, and MMP-1 ( P<0.0001) and MMP-2 ( P<0.038) in the annulus. In parallel, the proliferation of disc cells and matrix degeneration (granular changes and mucous degeneration) were related to MMP expression. Likewise, enzymatic activity was seen in association with cleft formation. Our data suggest that major MMPs play an important role in the degradation of the IVD. This is evidenced by the high correlation of MMP expression with the formation of clefts and tears. These findings implicate a leading function for MMPs in IVD degeneration resulting in the loss of normal disc function, eventually leading to low-back pain.


Asunto(s)
Resorción Ósea/enzimología , Disco Intervertebral/enzimología , Vértebras Lumbares , Metaloproteinasas de la Matriz/metabolismo , Enfermedades de la Columna Vertebral/enzimología , Enfermedades de la Columna Vertebral/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Niño , Preescolar , Femenino , Feto , Humanos , Inmunohistoquímica , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Fagocitos/metabolismo , Fagocitos/patología , Enfermedades de la Columna Vertebral/metabolismo , Enfermedades de la Columna Vertebral/fisiopatología , Distribución Tisular
3.
Int J Oncol ; 18(4): 669-81, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11251160

RESUMEN

The proper structure of the extracellular matrix, in particular of the basement membrane and the adjacent interstitial matrix, are essential prerequisites for a proper function of tissues. Invasive growth in malignant tumors is associated with a destruction of various matrix structures. Due to extensive recent analyses significant advances have been made in the knowledge of the structure of the extracellular matrix, the composition of its most important constituents, their metabolism and that of matrix degrading enzymes. This information provides insight into the pathophysiology of malignant growth. Thereby, it has been shown that malignant tumor growth is associated with a loss of basement membrane (BM) material which, however, disappears not homogeneously, but affects various BM components to different degree. The loss of an intact BM as the first barrier is therefore the initial step of tumor invasion. Despite this loss there is evidence that the de novo synthesis of BM constituents in tumor and adjacent stromal cells is enhanced. Thus, it is obvious that BM material is degraded during the invasion process to significant degree. In addition, since there is a positive correlation between the amount of retained peritumoral BM and a higher degree of tumor cell differentiation the amount of retained BM material seems to represent a marker for the biological behaviour of the tumor cells. The loss of BM material is well explained by a significant expression of major matrix degrading enzymes, the matrix metalloproteinases (MMPs) both on the mRNA and protein level. Here again, there is considerable data indicating that both tumor and stroma cells are involved in the MMP synthesis. In addition to the loss of BM substances, the interstitial extracellular matrix (ECM) is disarranged. This disarrangement may comprise enhanced de novo synthesis ("desmoplasia") or dissolution by distinct MMPs (collagenases, such as MMP-1) reflecting obviously different reaction statuses of the stromal cells. Finally, significant work has been done on the elucidation of the role of regulating cytokine systems. To this regard, particular attention has been paid to the TGF-beta system and it has been shown that the major three isoforms of TGF-betas are upregulated both in tumor and stroma cells. Since the TGF-beta-effect is mainly mediated by a particular signalling system via the TGF-beta-receptors (TBRs), the investigation of this system has provided considerable insight into the role of TBRs which are now known to represent the most potent tumor suppressor genes. Thus frequent mutations in the TBR-II gene, one of the three TBRs, in various carcinomas suggest that these molecular alterations are responsible for both the loss of the control of cellular proliferation (in tumor cells) and altered matrix metabolism (in tumor and stroma cells). The further analysis of this major cytokine system therefore will provide us with major insights into the molecular abnormalities of invasive tumor growth.


Asunto(s)
Membrana Basal/fisiología , Matriz Extracelular/fisiología , Invasividad Neoplásica , Neoplasias/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Membrana Basal/ultraestructura , Colágeno/metabolismo , Colágeno/farmacología , Regulación de la Expresión Génica , Humanos , Metaloproteinasas de la Matriz/metabolismo , Neoplasias/patología , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/genética
4.
Anticancer Res ; 21(6A): 3821-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11911253

RESUMEN

In the present study we investigated the presence, amount and activity of matrix metalloproteinases (MMPs)-1, -2, -3, -7, -8, -9, -10, -11 and -13 and TIMP-1 in three well-defined breast cancer cell lines with different biological behaviour; i.e. poorly-invasive MCF-7 cells, invasively growing MDA-MB-231 cells and invasive and highly-metastatic MDA-MB-435 cells. The parallel immunocytochemical determination of the degree of cellular differentiation, as monitored by the immunocytochemical expression of cytokeratins (CK), confirmed differences in the tumor cell differentiation. Thereby, MCF-7 cells expressed more glandular CKs than MDA-MB-231 cells, while MDA-MB-435 cells were only labelled by pancytokeratin markers, but neither by glandular nor by squamous epithelial CKs. Conditioned media were analyzed for the presence of MMPs and TIMP-1 using Western blot with specific polyclonal antibodies and for gelatinolytic and caseinolytic activity by zymography. In addition, the cellular pool of several MMPs was investigated by immunocytochemistry. An enhanced cytoplasmatic staining for MMP-3 and -9, MMP-1, -10 and -11 was seen in the highly metastatic cells at almost equal levels, while MMP-2 revealed only a minor intracellular staining in all three cell lines. Western blots of conditioned media showed enhanced amounts of MMP-1, -3, -7, -10 and -11 in media of the two metastatic cell lines. Casein zymography correlated with the results of the MMP-1 Western blots. By means of gelatin zymography, MMP-2 and -9 were detectable in cell culture supematants of all the three cell lines, while gelatinolytic activity was elevated in the media of the more malignant MDA-MB-435 cells. Separate addition of EDTA or Pefa bloc SL partially inhibited the gelatinoltic activity indicating the presence of metallo- and serine proteinases, respectively; combined application of both inhibitors resulted in a complete suppression of activity. We provide evidence that the deviation expression in secretion of various MMPs in breast cancer cell lines of different tumorigenicity correlates with the biological behaviour of these cells, ie. the more malignant cells synthesize more MMPs than the less malignant ones. In addition, the secretion of MMP-1, -3, -7, -10 and -11 was enhanced in the malignant MDA-MB-231 and -435 cells when compared to the corresponding intracellular pool. This analysis confirms previous results obtained in a keratinocyte tumor cell model and provides evidence for a more general biological association between MMP-expression and tumor cell growth.


Asunto(s)
Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Metaloproteinasas de la Matriz/metabolismo , Diferenciación Celular/fisiología , Medios de Cultivo Condicionados , Humanos , Inmunohistoquímica , Isoenzimas/metabolismo , Queratinas/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Células Tumorales Cultivadas
5.
Biol Chem ; 381(5-6): 497-507, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10937882

RESUMEN

In order to investigate the correlations between constitutive proteinase expression and the degree of tumorigenicity of cancer cells we have studied a model system of three keratinocyte cell lines. RT-PCR studies showed that the cell lines express the genes of matrix metalloproteinase-2, -3, -7, -9, -10 and -11, indicating that they are able to synthesize the corresponding enzymes. Actual MMP synthesis was proven by zymography and Western blotting. In conditioned media gelatinolytic activities or immunoreactive forms of MMP-2, -3, -7, -9, -10 and -11 were detected. The signal intensities showed that MMP secretion increases in the order HaCaT < A5 < or = II-4RT, whereas only MMP-11 is secreted by all cell lines in equal amounts. Intracellularly, enhanced levels of one or both of the tumorigenic variants were only found for MMP-3, -9 and -10, suggesting special functions of these intracellular MMP pools for the tumorigenic cell lines. For MMP-11 exclusive expression in stromal fibroblasts of tumor tissues is widely accepted; however, our results and three other recent reports demonstrate that this concept is not generally valid. In conclusion, the three keratinocyte cell lines investigated here represent an excellent model for studying constitutive expression and secretion of MMPs in correlation to the degree of in vivo tumorigenicity.


Asunto(s)
Queratinocitos/enzimología , Metaloproteinasas de la Matriz/metabolismo , Secuencia de Bases , Western Blotting , Extractos Celulares , Línea Celular , Línea Celular Transformada , Medios de Cultivo Condicionados , Cartilla de ADN , Gelatina/metabolismo , Humanos , Metaloproteinasas de la Matriz/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
6.
Biol Chem ; 381(5-6): 509-16, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10937883

RESUMEN

We investigated cells and conditioned media of the three human keratinocyte cell lines HaCaT (non-tumorigenic), A5 (benign, tumorigenic) and II-4RT (malignant, tumorigenic) with regard to production and secretion of the collagenases-1 to -3 (MMP-1, MMP-8 and MMP-13) and TIMP-1 using semi-nested RT-PCR, Western blots, ELISA, immunocytochemistry and casein zymography. Transcripts of MMP-1, -8, -13 and TIMP-1 were detected in all cell lines by RT-PCR and the corresponding proteins were found in the cytoplasm of all three cell lines by Western blot analysis and/or immunocytochemistry. The conditioned media of the malignant II-4RT cells contain significantly more MMP-1 and MMP-8 than those of HaCaT or A5 as evidenced by immunoblotting and ELISA. In addition to the presence of latent MMP-1, zymography also detected the active form of this enzyme. TIMP-1 was found only in extracts of all three cell lines, predominantly in A5. This study clearly indicates that the epithelial tumor cells synthesize different collagenases and TIMP-1. The malignant clone secretes increased amounts of distinct collagenases compared to the non-tumorigenic cell line, thereby verifying a correlation between biological behaviour and the amount of collagenases. In addition, we provide clear evidence that MMP-8 is not exclusively found in polymorphonuclear granulocytes, but also in keratinocyte cell lines.


Asunto(s)
Colágeno/metabolismo , Queratinocitos/enzimología , Metaloproteinasas de la Matriz/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Secuencia de Bases , Western Blotting , Extractos Celulares , Línea Celular , Medios de Cultivo Condicionados , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Humanos , Hidrólisis , Inmunohistoquímica , Queratinocitos/metabolismo , Metaloproteinasas de la Matriz/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidor Tisular de Metaloproteinasa-1/genética
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