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1.
Urologe A ; 45(11): 1415-6, 1418-23, 2006 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-16865382

RESUMEN

BACKGROUND: Clinical pathways are directions for standardised treatment processes for different diseases or procedures in a hospital. These pathways are developed within a team of several professions and are used as order and procedure sheets. Experiences with this element of quality management are limited in Germany. METHODS: The development and the implementation process of 15 pathways in a urological department are described. A clinical pathway for female incontinence surgery (suburethral tape) is presented as an example. The effects of the pathways are evaluated on a routine basis. RESULTS: Seventy-two percent of the patients were treated according to a clinical pathway. The advantages of clinical pathways are a better structuring and transparency of medical processes, a reduction of documentation, improvements in medical education and savings in time, hospital stay of the patients and costs. Expenses for pharmaceuticals were significantly reduced in connection with development of the pathways. CONCLUSIONS: The implementation of clinical pathways is a complex but rewarding project. It can be expected that clinical pathways will be rapidly distributed in the near future and that they will contribute to improvements of health care quality.


Asunto(s)
Vías Clínicas/organización & administración , Departamentos de Hospitales , Enfermedades Urológicas/terapia , Urología , Femenino , Alemania , Adhesión a Directriz , Humanos , Capacitación en Servicio , Grupo de Atención al Paciente/organización & administración , Garantía de la Calidad de Atención de Salud/organización & administración , Incontinencia Urinaria/terapia , Enfermedades Urológicas/diagnóstico
2.
Parasitol Res ; 97(3): 201-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15997410

RESUMEN

Mastomys coucha and jirds infected with Acanthocheilonema viteae, a filarial species free of endosymbiontic bacteria of the genus Wolbachia, suffer lethal side effects after effective microfilaricidal therapy with diethylcarbamazine and levamisole, whereas, M. coucha infected with the Wolbachia-infested species Brugia malayi or Litomosoides carinii tolerate corresponding treatment. Mortality in A. viteae infected, treated animals varied with microfilariae density in the blood. It was up to 100% in highly microfilaraemic M. coucha and jirds, but low or absent in animals with low microfilariae counts. Deaths occurred in most cases 5-24 h after treatment. Characteristic symptoms in animals, which died subsequently were a rapid drop in body temperature by 4-7 degrees C, an increase in hematokrit values by up to 10% and a moderate blood acidosis. Lethal effects in A. viteae infections did not depend on a particular status of hypersensitivity of the animals since desensitization procedures, which protected infected M. coucha against an otherwise lethal intravenous challenge with A. viteae homogenate did not protect against adverse reactions to a subsequent microfilaricidal treatment. The animals were protected from treatment induced death by injection of N-LMMA. Thus the final morbific agent seems NO. The data show that adverse effects after effective microfilaricidal therapy may be caused by microfilariae derived components different from Wolbachia-released LPS.


Asunto(s)
Dietilcarbamazina/efectos adversos , Infecciones por Dipetalonema/tratamiento farmacológico , Dipetalonema , Filaricidas/efectos adversos , Levamisol/efectos adversos , Lipopolisacáridos , Enfermedades Parasitarias en Animales/tratamiento farmacológico , Animales , Dipetalonema/inmunología , Dipetalonema/aislamiento & purificación , Infecciones por Dipetalonema/mortalidad , Infecciones por Dipetalonema/parasitología , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Gerbillinae , Lipopolisacáridos/metabolismo , Microfilarias/efectos de los fármacos , Muridae , Enfermedades Parasitarias en Animales/mortalidad , Enfermedades de los Roedores/tratamiento farmacológico , Enfermedades de los Roedores/parasitología , Especificidad de la Especie , Tasa de Supervivencia , Wolbachia/inmunología
3.
Dev Growth Differ ; 43(4): 327-42, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11473540

RESUMEN

Embryonic development begins with cleavage of the fertilized egg. Cleavage comprises two major processes: cytokinesis and formation of a polarized epithelial cell layer. The focus of this review is comparison of the generation of membrane polarity during embryonic cleavage in three different developmental model systems. In mammalian embryos, as exemplified by analysis of the mouse, generation of distinct membrane domains is uncoupled from cleavage divisions and is initiated in a specific developmental phase, called compaction. In Xenopus laevis embryos, generation of polarized blastomeres occurs simultaneously with cytokinesis. The origin of specific membrane domains of X. laevis polar blastomeres, however, can be traced back to oogenesis. Finally, in Drosophila melanogaster, generation of polarized cells occurs at cellularization. The relevance of cell adhesion, cell junctions and cytocortical scaffolds will be discussed for each of the model systems. Despite enormous morphologic differences, the three models share many common features; in particular, many important molecular interactions are conserved.


Asunto(s)
Membrana Celular/fisiología , Polaridad Celular/fisiología , Embrión de Mamíferos/fisiología , Desarrollo Embrionario , Desarrollo Embrionario y Fetal , Animales , Blastocisto/citología , Blastocisto/fisiología , Blastocisto/ultraestructura , Blastómeros/fisiología , Blastómeros/ultraestructura , División Celular/fisiología , Drosophila melanogaster/embriología , Embrión de Mamíferos/citología , Embrión de Mamíferos/ultraestructura , Embrión no Mamífero/citología , Embrión no Mamífero/ultraestructura , Uniones Intercelulares/fisiología , Uniones Intercelulares/ultraestructura , Ratones , Xenopus laevis/embriología
4.
Development ; 128(5): 801-13, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11171404

RESUMEN

Transcriptional control during early Drosophila development is governed by maternal and zygotic factors. We have identified a novel maternal transcriptional regulator gene, lilliputian (lilli), which contains an HMG1 (AT-hook) motif and a domain with similarity to the human fragile X mental retardation FMR2 protein and the AF4 proto-oncoprotein. Embryos lacking maternal lilli expression show specific defects in the establishment of a functional cytoskeleton during cellularization, and exhibit a pair-rule segmentation phenotype. These mutant phenotypes correlate with markedly reduced expression of the early zygotic genes serendipity alpha, fushi tarazu and huckebein, which are essential for cellularization and embryonic patterning. In addition, loss of lilli in adult photoreceptor and bristle cells results in a significant decrease in cell size. Our results indicate that lilli represents a novel pair-rule gene that acts in cytoskeleton regulation, segmentation and morphogenesis.


Asunto(s)
Tipificación del Cuerpo , Citoesqueleto/metabolismo , Proteínas de Drosophila , Drosophila melanogaster/embriología , Embrión no Mamífero/fisiología , Proteínas de Homeodominio/metabolismo , Proteínas Nucleares/metabolismo , Factores de Transcripción , Actinas/metabolismo , Secuencia de Aminoácidos , Animales , Tamaño de la Célula , Citoesqueleto/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Drosophila melanogaster/genética , Embrión no Mamífero/citología , Femenino , Citometría de Flujo , Factores de Transcripción Fushi Tarazu , Regulación del Desarrollo de la Expresión Génica , Genes de Insecto , Genes Reporteros/genética , Proteínas de Homeodominio/genética , Humanos , Hibridación in Situ , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Microscopía Confocal , Microscopía Fluorescente , Microscopía por Video , Microtúbulos/metabolismo , Datos de Secuencia Molecular , Proteínas Nucleares/química , Proteínas Nucleares/genética , Células Fotorreceptoras de Invertebrados/citología , Células Fotorreceptoras de Invertebrados/embriología , Células Fotorreceptoras de Invertebrados/metabolismo , ARN Mensajero/metabolismo , Alineación de Secuencia , Alas de Animales/anatomía & histología
5.
Dev Dyn ; 218(1): 52-67, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10822259

RESUMEN

The cell biology of polarized epithelial cells is a field of major interest to cell and developmental biologists. In addition to the study of epithelial cells in tissue culture, genetically tractable systems have been employed to examine the functional importance of individual molecules. Here I review recent progress that has been made using Drosophila as a model system to study apical-basal epithelial cell polarity. In this system, a large number of genes have been identified that are essential for the development and maintenance of the apical-basal polarity of epithelial cells in different developmental contexts. In this article, the recent progress in three models, i.e., establishment of the ectoderm and midgut epithelia during embryogenesis, epithelial polarity of imaginal discs, and epithelial development of the follicle cells during oogenesis will be discussed.


Asunto(s)
Polaridad Celular/genética , Drosophila/genética , Células Epiteliales/citología , Uniones Intercelulares/genética , Animales , Drosophila/citología
6.
Cell ; 98(4): 453-63, 1999 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-10481910

RESUMEN

Drosophila Reaper (RPR), Head Involution Defective (HID), and GRIM induce caspase-dependent cell death and physically interact with the cell death inhibitor DIAP1. Here we show that HID blocks DIAP1's ability to inhibit caspase activity and provide evidence suggesting that RPR and GRIM can act similarly. Based on these results, we propose that RPR, HID, and GRIM promote apoptosis by disrupting productive IAP-caspase interactions and that DIAP1 is required to block apoptosis-inducing caspase activity. Supporting this hypothesis, we show that elimination of DIAP1 function results in global early embryonic cell death and a large increase in DIAP1-inhibitable caspase activity and that DIAP1 is still required for cell survival when expression of rpr, hid, and grim is eliminated.


Asunto(s)
Apoptosis/fisiología , Inhibidores de Caspasas , Proteínas de Drosophila , Drosophila melanogaster/fisiología , Proteínas de Insectos/fisiología , Naranja de Acridina , Animales , Apoptosis/genética , Drosophila melanogaster/embriología , Drosophila melanogaster/genética , Epistasis Genética , Colorantes Fluorescentes , Genes Letales , Etiquetado Corte-Fin in Situ , Proteínas Inhibidoras de la Apoptosis , Proteínas de Insectos/genética , Morfogénesis/genética , Neuropéptidos/genética , Neuropéptidos/fisiología , Péptidos/genética , Péptidos/fisiología , Proteínas Recombinantes de Fusión/fisiología , Saccharomyces cerevisiae/citología
7.
Development ; 126(3): 577-86, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9876186

RESUMEN

Wingless signaling plays a central role during epidermal patterning in Drosophila. We have analyzed zygotic requirements for Wingless signaling in the embryonic ectoderm by generating synthetic deficiencies that uncover more than 99% of the genome. We found no genes required for initial wingless expression, other than previously identified segmentation genes. In contrast, maintenance of wingless expression shows a high degree of zygotic transcriptional requirements. Besides known genes, we have identified at least two additional genomic regions containing new genes involved in Wingless maintenance. We also assayed for the zygotic requirements for Wingless response and found that no single genomic region was required for the cytoplasmic accumulation of Armadillo in the receiving cells. Surprisingly, embryos homozygously deleted for the candidate Wingless receptor, Dfrizzled2, showed a normal Wingless response. However, the Armadillo response to Wingless was strongly reduced in double mutants of both known members of the frizzled family in Drosophila, frizzled and Dfrizzled2. Based on their expression pattern during embryogenesis, different Frizzled receptors may play unique but overlapping roles in development. In particular, we suggest that Frizzled and Dfrizzled2 are both required for Wingless autoregulation, but might be dispensable for late Engrailed maintenance. While Wingless signaling in embryos mutant for frizzled and Dfrizzled2 is affected, Wingless protein is still internalized into cells adjacent to wingless-expressing cells. Incorporation of Wingless protein may therefore involve cell surface molecules in addition to the genetically defined signaling receptors of the frizzled family.


Asunto(s)
Proteínas de Drosophila , Drosophila/embriología , Proteínas de la Membrana/genética , Proteínas Proto-Oncogénicas/fisiología , Transducción de Señal/fisiología , Animales , Receptores Frizzled , Proteínas de la Membrana/fisiología , Fenotipo , Ratas , Receptores Acoplados a Proteínas G , Receptores de Neurotransmisores/genética , Receptores de Neurotransmisores/fisiología , Mapeo Restrictivo , Proteína Wnt1 , Cigoto/fisiología
9.
Hepatogastroenterology ; 45(21): 691-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9684118

RESUMEN

BACKGROUND/AIMS: The etiology and pathogenesis of ulcerative colitis and Crohn's disease remain unclear, so that exact causal therapy is not yet possible. In our UC and CD patients, viral infections, particularly of the upper respiratory tract, aggravated the underlying disease. This had led us to use in-situ hybridization to investigate intestinal mucosa for viral agents such as HSV I + II- and Epstein-Barr virus DNA. We found these DNA in the cell nuclei in the surface and glandular epithelia of the affected mucosa of the small intestine and the colon. These findings indicated that viruses may exacerbate these inflammatory bowel diseases. METHODOLOGY: Over a period of 1-4.7 years, we treated 16 patients aged 25-65 with Crohn's disease (12 patients) or ulcerative colitis (four patients). In 14 patients, inflammatory bowel disease had been diagnosed years before (mean, 15.3 years). When we started therapy, 75% of the patients with Crohn's disease had extra-intestinal manifestations; and the CDAI after Best averaged considerably above 150. All patients had been taking either prednisone or prednisolone and/or 5-ASA or SASP and/or azathioprine or metronidazole for many years. Using PCR, mucosal specimens of the small intestine and/or the colon were tested for EBV-, HSV I + II, HHV6- and CMV DNA. In 12 of the 16 patients. EBV- and/or HHV6 DNA were found in the affected mucosa. Since interferon alpha administration has proven effective in chronic hepatitis-B therapy, we decided to administer interferon alpha 2a (13,46,47,55). After stopping the above-mentioned basic therapies, we commenced treatment with 6 million units of interferon alpha 2a subcutaneously 3 times per week for at least six months. Four of the patients showed no signs of improvement, and their therapy was stopped after three months. For the others, therapy was continued until patients were clinically symptom-free and viral DNA could no longer be traced in their mucosal biopsies. RESULTS: With interferon therapy, 12 of the 16 patients showed slow but continual improvement. Particularly impressive was the remission of the extra-intestinal manifestations, which did not recur in any patient during interferon therapy. Four patients did not show any improvement, and the clinical symptom of diarrhea continued. Two patients with ulcerative colitis suffered relapses three and four years later, after severe bouts of para-influenza of the upper respiratory tract. In these two patients, EBV- and HHV6 DNA was found in the inflamed mucosa of the colon. Renewed therapy with interferon alpha 2a successfully cleared up the inflammation. The patient group needed an average of eight weeks to become clinically symptom-free, and an average of six months to achieve complete virus elimination in the pathologically altered mucosa. CONCLUSIONS: For herpesvirus-associated ulcerative colitis and Crohn's disease, interferon alpha 2a treatment should be started as early as possible to prevent disease becoming chronic. Whether this kind of antiviral treatment will be as effective in the long term, and whether malignant transformation (herpes viruses are potential tumor inducers) will be delayed or prevented, are questions that can be answered only by future long-term studies.


Asunto(s)
Infecciones por Herpesviridae/terapia , Enfermedades Inflamatorias del Intestino/terapia , Enfermedades Inflamatorias del Intestino/virología , Interferón-alfa/uso terapéutico , Adulto , Anciano , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/terapia , Colitis Ulcerosa/virología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/terapia , Enfermedad de Crohn/virología , Citomegalovirus/genética , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/terapia , ADN Viral/aislamiento & purificación , Infecciones por Herpesviridae/complicaciones , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 6/genética , Humanos , Hibridación in Situ , Enfermedades Inflamatorias del Intestino/complicaciones , Interferón alfa-2 , Mucosa Intestinal/virología , Persona de Mediana Edad , Proteínas Recombinantes , Infecciones del Sistema Respiratorio/complicaciones
10.
J Cell Biol ; 134(1): 149-63, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8698811

RESUMEN

Cellularization of the Drosophila embryo results in the formation of a cell monolayer with many characteristics of a polarized epithelium. We have used antibodies specific to cellular junctions and nascent plasma membranes to study the formation of the zonula adherens (ZA) in relation to the establishment of basolateral membrane polarity. The same approach was then used as a test system to identify X-linked zygotically active genes required for ZA formation. We show that ZA formation begins during cellularization and that the basolateral membrane domain is established at mid-gastrulation. By creating deficiencies for defined regions of the X chromosome, we have identified genes that are required for the formation of the ZA and the generation of basolateral membrane polarity. We show that embryos mutant for both stardust (sdt) and bazooka (baz) fail to form a ZA. In addition to the failure to establish the ZA, the formation of the monolayered epithelium is disrupted after cellularization, resulting in formation of a multilayered cell sheet by mid-gastrulation. SEM analysis of mutant embryos revealed a conversion of cells exhibiting epithelial characteristics into cells exhibiting mesenchymal characteristics. To investigate how mutations that affect an integral component of the ZA itself influence ZA formation, we examined embryos with reduced maternal and zygotic supply of wild-type Arm protein. These embryos, like embryos mutant for both sdt and baz, exhibit an early disruption of ZA formation. These results suggest that early stages in the assembly of the ZA are critical for the stability of the polarized blastoderm epithelium.


Asunto(s)
Blastodermo/citología , Adhesión Celular , Polaridad Celular , Proteínas de Drosophila , Drosophila melanogaster/embriología , Genes de Insecto , Uniones Intercelulares/ultraestructura , Proteínas/fisiología , Transactivadores , Animales , Proteínas del Dominio Armadillo , Mapeo Cromosómico , Drosophila melanogaster/genética , Células Epiteliales , Técnica del Anticuerpo Fluorescente Indirecta , Gástrula/citología , Regulación del Desarrollo de la Expresión Génica , Glicoproteínas de Membrana/metabolismo , Factores de Transcripción , Cromosoma X
11.
Ann Hematol ; 72(6): 383-6, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8767109

RESUMEN

Two cases of lymphoma-associated acquired C 1-inhibitor deficiency are described. In both patients, C 1-inhibitor deficiency and related symptoms preceded the diagnosis of the underlying neoplasm by several months. C 1-inhibitor deficiency was most likely due to consumption following immunocomplex formation. In both patients, a close relationship between low levels of C 1-inhibitor and tumor relapse was observed during follow-up. These findings indicate that measurement of C 1-inhibitor and complement factor C4 can be used as markers of disease activity in affected patients.


Asunto(s)
Angioedema/etiología , Proteínas Inactivadoras del Complemento 1/deficiencia , Leucemia Linfocítica Crónica de Células B/complicaciones , Linfoma no Hodgkin/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Neoplasias Primarias Múltiples
12.
Am J Emerg Med ; 13(3): 259-61, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7755813

RESUMEN

There have been a limited number of studies assessing the impact of attending physician supervision of residents in the emergency department (ED). The objective of this study is to describe the changes in patient care when attending emergency physicians (AEPs) supervise nonemergency medicine residents in a university hospital ED. This was a prospective study including 1,000 patients, 32 second- and third-year nonemergency medicine residents and eight AEPs. The AEPs classified changes in care for each case as major, minor, or none, according to a 40-item data sheet list. There were 153 major changes and 353 minor changes by the AEP. The most common major changes were ordering laboratory or x-ray tests that showed a clinically significant abnormality, and eliciting important physical exam findings. Potentially limb- or life-threatening errors were averted by the AEP in 17 patients. Supervision of nonemergency medicine residents in the ED resulted in frequent and clinically important changes in patient care.


Asunto(s)
Medicina de Emergencia/educación , Servicio de Urgencia en Hospital/organización & administración , Internado y Residencia/normas , Cuerpo Médico de Hospitales/normas , Errores Diagnósticos , Hospitales Universitarios , Humanos , Cuerpo Médico de Hospitales/educación , Pennsylvania , Estudios Prospectivos , Calidad de la Atención de Salud
13.
Dev Dyn ; 202(4): 405-20, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7626797

RESUMEN

The Xenopus blastula consists of two morphologically distinct cell types. Polarized epithelial cells build up the embryonic surface and fence off an inner non-polarized cell population. We examined the establishment of this early functional cell diversification in the embryo by single cell analysis, in vitro cell culture, and transplantation experiments. Single blastomeres from a 64-cell embryo (1/64 cells) exhibit several features of polarized cells. The plasma membrane of 1/64 cells consists of an apical domain, which is inherited from the original egg membrane, and a basolateral domain derived from newly formed membrane during cleavage. These are inherent, cell-autonomous properties of the blastomeres, as they form and are maintained in blastomeres raised in the absence of any cell interactions in calcium free medium. Upon in vitro culture a single 1/64 cell gives rise to an aggregate of two different cell types. Cells carrying a part of the former egg membrane domain differentiate into polarized epithelial cells, whereas cells lacking this membrane domain are not polarized. These results demonstrate that the inclusion of the egg membrane, rather than external signals related to the position of a cell in the intact embryo, is required for the apical/basolateral differentiation of the surface epithelium. This view is supported by cell transplantation studies. A single 1/64 cell was implanted into the blastocoel of a stage 8 blastula embryo. The progeny of the implanted cell proliferate within the host embryo and split into two morphologically distinct populations with different cell behaviours. Cells incorporating a part of the egg membrane form coherent patches of polarized epithelial cell sheets in the interior of the host embryo. In contrast, cells lacking egg membrane do not exhibit any characteristics of polarized cells and eventually spread into different regions of the host embryo. Our results show that the egg membrane and/or components of the submembrane cortex play a determinative role in the formation of the blastula epithelium.


Asunto(s)
Blastómeros/citología , Polaridad Celular , Xenopus laevis/embriología , Animales , Blastocisto/citología , Blastómeros/metabolismo , Blastómeros/trasplante , Agregación Celular , Embrión no Mamífero/citología , Células Epiteliales , Uniones Intercelulares/ultraestructura , Microscopía Electrónica , Morfogénesis , Trasplante Heterotópico
15.
Medinfo ; 8 Pt 2: 1491-5, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8591481

RESUMEN

The availability and prominence of telecommunication technology has spurred research into generic wide area health care networks. Electronic exchange of patient data supposedly results in cost efficiencies, increased accessibility to health care resources, and improved delivery of health care services. Although a number of pilot networks have been built, none yet have a broad, heterogeneous base of users and applications. Properties of the health care process and delivery system delay the acceptance of generic wide area networks and end-user computer applications. As the technical problems seem well understood, it seems advisable to investigate these factors in telemedical research.


Asunto(s)
Redes de Comunicación de Computadores/organización & administración , Atención a la Salud/organización & administración , Colombia Británica , Redes de Comunicación de Computadores/legislación & jurisprudencia , Redes de Comunicación de Computadores/normas , Costos y Análisis de Costo , Laboratorios/organización & administración , Programas Informáticos , Integración de Sistemas , Telecomunicaciones/tendencias
16.
Cell Adhes Commun ; 2(6): 511-20, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7743137

RESUMEN

By immunological methods, we show that the monoclonal antibody 6D5 which reacts specifically with Xenopus laevis XB/U-cadherin, also binds to mouse P-cadherin and to chicken B-cadherin but not to the respective E-cadherins (L-CAM) or other "classical" cadherins in these species. In the first extracellular domain, three amino acid residues are identified that are shared by frog XB/U-cadherin, chicken B-cadherin and mammalian P-cadherins but not by the other "classical" cadherins. With few exceptions, the other cadherins possess residues at these positions that are also characteristic of each type of cadherin. Moreover, the expression patterns of P-, B-, and XB/U-cadherin in mouse, chicken and frog are more similar to each other than they are to those of the E-cadherins, L-CAM or other classical cadherins. Taken together, our results suggest that mammalian P-cadherins, chicken B-cadherin and frog XB/U-cadherin are closely related, if not homologous, molecules. A number of differences in the expression patterns between P-, B-, and XB/U-cadherin indicate that these molecules assume differential morphogenetic roles in different species.


Asunto(s)
Cadherinas/genética , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Cadherinas/química , Cadherinas/inmunología , Pollos , Reacciones Cruzadas , Expresión Génica , Ratones , Datos de Secuencia Molecular , Estructura Molecular , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Distribución Tisular , Xenopus laevis
17.
Mech Dev ; 47(3): 213-23, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7531482

RESUMEN

Three maternal cadherins have been reported to occur in the pregastrula Xenopus embryo. EP- and XB-cadherin are distinguished by their distinct cDNA sequences. U-cadherin has been characterized by its reaction with a specific monoclonal antibody (mAb 6D5). Thus far, lack of specific probes that discriminate between these molecules has prevented their identification as distinct cadherins. We now demonstrate by means of RNase protection assays that both EP- and XB-cadherin mRNAs are present in oocytes and mature eggs. By use of the Xenopus cadherin proteins expressed in mammalian cell lines, we find that mAb 6D5 crossreacts with XB-cadherin, but not with EP-cadherin. The major fraction of the maternal cadherins does not contain the 6D5 epitope and probably represents EP-cadherin. A minor fraction carries the 6D5 epitope indicative for the XB- and U-type of cadherins. We have termed this fraction XB/U-cadherin. The function of maternal cadherins was examined by in vitro cell adhesion assays. A newly developed antiserum with a broad specificity for various Xenopus cadherins efficiently blocks all calcium dependent cell adhesion in the early embryo. We conclude that the maternal cadherins play a central role in interblastomere adhesion in the early embryo and comprise at least two discrete cadherin forms, EP- and XB/U-cadherin.


Asunto(s)
Cadherinas/análisis , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Epítopos , Femenino , Datos de Secuencia Molecular , Ribonucleasas , Xenopus
18.
Virchows Arch ; 424(6): 647-51, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8055159

RESUMEN

Paraffin embedded tissue of 49 stage C and 27 stage B prostate adenocarcinomas was investigated by flow cytometry. All patients were treated by radical prostatectomy with pelvic lymphadenectomy and followed up for 5-10 years. The tumour was separated from the benign tissue to increase the proportion of tumour cells. Ten stage C and seven stage B carcinomas had to be excluded because of poor fixation. Six of the 39 (15%) stage C and 1/20 (5%) stage B carcinomas were aneuploid. Cell cycle analysis was done with correction for sliced nuclei and background subtraction. The threshold between carcinomas with low and with increased ("tetraploid") G2M-fraction was determined by comparing carcinomas with and without tumour progression. Sixty-seven percent of the patients with non-euploid stage C carcinomas and 11% of those with euploid carcinomas suffered from tumour progression (P < 0.01). The respective values for the stage B carcinomas were 67% and 6% (P < 0.01). These results demonstrate the strong prognostic impact of DNA-ploidy and G2M-fractions for each individual patient.


Asunto(s)
Carcinoma/genética , Fase G2 , Ploidias , Neoplasias de la Próstata/genética , Adulto , Anciano , Carcinoma/mortalidad , Carcinoma/patología , ADN de Neoplasias/genética , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología
19.
Recent Results Cancer Res ; 133: 17-21, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8296067
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