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1.
Ned Tijdschr Geneeskd ; 162: D2221, 2018.
Artículo en Holandés | MEDLINE | ID: mdl-29493471

RESUMEN

Thomas Hodgkin was the first to describe a malignant lymphoma, which would later carry his name. Over the course of time, other lymphoid malignancies were recognised that showed no similarity with Hodgkin's disease. They were subsequently named after the - at that time - applicable morphological nomenclature of the associated cells. Later, nomenclature also took immunological features into consideration. However, we still describe the group of lymphomas recognised after Hodgkin's discovery as 'not being Hodgkin's disease', i.e. non-Hodgkin lymphoma. We feel it is unjust that not many people know about the man behind this prominent disease. In this article, an historic overview is given of Thomas Hodgkin, 'his' lymphoma and the other malignant lymphomas.


Asunto(s)
Enfermedad de Hodgkin/historia , Linfoma , Historia del Siglo XIX , Humanos , Linfoma/clasificación , Linfoma/historia , Terminología como Asunto
2.
Tissue Antigens ; 69(4): 334-7, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17389017

RESUMEN

Interaction of donor natural killer (NK)-cell-associated killer cell immunoglobulin-like receptors (KIRs) with the patient's human leukocyte antigen-C (HLA-C) ligands can result in an alloreactive NK response after haematopoietic stem cell transplantation. In many retrospective studies, additional HLA-C-typing data are required to predict NK-cell alloreactivity. We developed a Taqman assay using the quantitative polymerase chain reaction (Q-PCR) technique that facilitates HLA-C epitope typing, allowing the assignment of HLA-C group 1 or 2 alleles based on the dimorphism at residues 77 and 80 rather than based on the sequence specific priming (SSP) and sequence-based typing allele types. Q-PCR analysis for HLA-C epitope detection showed three clusters reflecting homozygous group 1 or 2 and heterozygous samples. This new approach introduces a quick HLA-C epitope screening method to define the presence of the ligand for the KIR-HLA-C interaction.


Asunto(s)
Epítopos/genética , Antígenos HLA-C/biosíntesis , Antígenos HLA-C/genética , Prueba de Histocompatibilidad/métodos , Células Asesinas Naturales/citología , Reacción en Cadena de la Polimerasa/métodos , Alelos , Cartilla de ADN/química , Antígenos HLA/genética , Histocompatibilidad , Homocigoto , Humanos , Ligandos
3.
Histopathology ; 48(4): 329-42, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16487355

RESUMEN

In many haematological conditions the only curative option is stem cell (SCT) or bone marrow (BM) transplantation. Little information exists about BM morphology following non-ablative engraftment. During the pretransplantation period and depending on the kind of pretreatment, there may be hypoplasia, residual disease and varying degrees of fibrosis. In the post-transplantation period, after 1-3 weeks of transfusion-dependent pancytopenia, the first signs of successful engraftment are indicated by the recurrence of neutrophils, monocytes and erythrocytes in the peripheral blood. In the BM there is slow regeneration of erythropoiesis, followed by the other lineages of haematopoiesis and increase in reticulin fibres or even a resolution of fibrosis. Diagnostic problems arise when neoplastic lympho- or haematopoiesis are maintained following transplantation. Moreover, there may be a significant graft versus tumour response reaction or an already relapsing disease needing aggressive treatment. On the other hand, a conspicuous dyshaematopoiesis should not be mistaken as representing a myelodysplastic syndrome. The presence of granulomas being treatment-related or a manifestation of intercurrent granulomatous disease has to be considered. More advanced knowledge of the histological features of regenerating BM will certainly aid the recognition of relapsing disease and is needed for the adequate reporting of post-transplant alterations associated with a successful or failing engraftment.


Asunto(s)
Médula Ósea/patología , Trasplante de Células Madre , Hematopoyesis , Humanos , Factores de Tiempo
4.
Ned Tijdschr Geneeskd ; 149(6): 283-8, 2005 Feb 05.
Artículo en Holandés | MEDLINE | ID: mdl-15730034

RESUMEN

Bone marrow biopsies are more and more often part of the work-up of patients with haematological disorders. The most important reason for this is the fact that a biopsy supplies important additional information compared to an aspirate alone. Biopsies are superior for the assessment of the bone marrow architecture, the vascularisation, the cellularity, the localisation and the extent of infiltrates and the degree of fibrosis. In addition, biopsy is a good way to evaluate the effects of therapy in the course of the disease. As is the case with aspirates, examination of a biopsy alone is usually sufficient for a correct diagnosis. However, a combination of both techniques makes possible an optimal assessment of the nature and extent of the disease process in the often very serious haematological conditions that we are dealing with here.


Asunto(s)
Examen de la Médula Ósea , Médula Ósea/patología , Enfermedades Hematológicas/diagnóstico , Biopsia con Aguja/métodos , Enfermedades Hematológicas/patología , Humanos
5.
Histopathology ; 42(4): 313-30, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12653943

RESUMEN

Allogeneic haematopoietic stem cell transplantation (i.e. bone marrow or peripheral blood stem cell transplantation) is a common procedure in the treatment of various haematological disorders such as aplastic anaemia, (pre)leukaemias, some malignant lymphomas, multiple myeloma and immunodeficiency states. Many of these patients develop erythematous skin lesions following transplantation. Although graft- versus-host disease is the major differential diagnosis in these situations, many other causes of erythema are encountered. The large number of transplant patients means that more and more pathologists are confronted with the challenging problem of making a correct diagnosis in these situations. In this review article we therefore describe the different causes of erythema and their differential diagnoses. In most cases the clinical presentation is related to the microscopical features. Besides acute and chronic graft-versus-host disease, we discuss the (common) drug reactions and non-specific features such as Sweet's syndrome, erythema nodosum and eosinophilic folliculitis. In addition, we deal with the recurrence of original diseases and infections. With this knowledge every pathologist should feel comfortable when looking at skin biopsies of patients after haematological stem cell transplantation.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/efectos adversos , Enfermedades de la Piel/etiología , Enfermedades de la Piel/patología , Diagnóstico Diferencial , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/patología , Humanos , Trasplante Homólogo/efectos adversos
6.
Eur Urol ; 41(4): 363-71, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12074805

RESUMEN

Prostate cancer is the most prevalent malignancy in males in the Western world and the second leading cause of male cancer death. Prostate specific antigen (PSA) based screening and case finding leads to identification of early stage prostate cancer. It is often difficult to discriminate between patients that need curative treatment and those that can be managed conservatively. Prognostic factors are used to make this clinical decision. Based on the classification proposed by the American College of Pathologists and the World Health Organisation, selected prognostic factors in prostate cancer are described. Clinical applicable factors are stage, grade and serum PSA. Prognostic factors that are not routinely used (for various reasons) are ploidy, histological type and cancer volume in needle biopsies. All other factors (including circulating tumour cells, angiogenesis, growth factors, proliferation rate, apoptosis, nuclear morphometry, neuroendocrine differentiation, loss of chromosomal regions, tumour suppresser genes and adhesion molecules) are promising as prognostic factor although currently their use in clinical decisions is not recommended. The role of these factors in prostate cancer growth and their predictive value are discussed. The rapid developments in molecular techniques allow assessment of structure or function of thousands of genes in a prostate biopsy sample. We expect that molecular characterisation of tumour material will become a clinically important tool to predict prognosis in patients with localised prostate cancer.


Asunto(s)
Neoplasias de la Próstata , Biomarcadores de Tumor/sangre , Humanos , Masculino , Células Neoplásicas Circulantes , Pronóstico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología
7.
Diagn Cytopathol ; 24(6): 426-34, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11391826

RESUMEN

Neural network-based screening (NNS) of cervical smears can be performed as a so-called "hybrid screening method," in which parts of the cases are additionally studied by light microscope, and it can also be used as "pure" NNS, in which the cytological diagnosis is based only on the digital images, generated by the NNS system. A random enriched sample of 985 cases, in a previous study diagnosed by hybrid NNS, was drawn to be screened by pure NNS. This study population comprised 192 women with (pre)neoplasia of the cervix, and 793 negative cases. With pure NNS, more cases were recognized as severely abnormal; with hybrid NNS, more cases were cytologically diagnosed as low-grade. For a threshold value > or = HSIL (high-grade squamous intraepithelial lesions), the areas under the receiver operating characteristic (ROC) curves (AUC) were 81% (95% CI, 75-88%) for pure NNS vs. 78% (95% CI, 75-81%) for hybrid NNS. For low-grade squamous intraepithelial lesions (LSIL), the AUC was significantly higher for hybrid NNS (81%; 95% CI, 77-85%) than for pure NNS (75%; 95% CI, 70-80%). Pure NNS provides optimized prediction of HSIL cases or negative outcome. For the detection of LSIL, light microscopy has additional value.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Tamizaje Masivo/métodos , Redes Neurales de la Computación , Displasia del Cuello del Útero/diagnóstico , Cuello del Útero/patología , Femenino , Humanos , Microscopía , Frotis Vaginal , Displasia del Cuello del Útero/patología
8.
Acta Cytol ; 45(1): 28-35, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11213501

RESUMEN

OBJECTIVE: To assess the difference in costs between PAPNET-assisted and conventional microscopy of cervical smears when used as a primary screening tool. STUDY DESIGN: We performed time measurements of the initial screening of smears by four cytotechnologists in one laboratory. Time was measured in 816 conventionally screened smears and in 614 smears with PAPNET-assisted screening. Data were collected on the components of initial screening, clerical activities and other activities in the total work time of cytotechnologists in the routine situation and on resource requirements for both techniques. RESULTS: PAPNET saved an average of 22% on initial screening time per smear. Due to costs of processing and additional equipment, the costs of PAPNET-assisted screening were estimated to be $2.85 (and at least $1.79) higher per smear than conventional microscopy. The difference in costs is sensitive to the rate of time saving, the possibility of saving on quality control procedures and the component of the initial screening time in the total work time of cytotechnologists. CONCLUSION: Although PAPNET is time saving as compared with conventional microscopy, the associated reduction in personnel costs is outweighed by the costs of scanning the slides and additional equipment. This conclusion holds under a variety of assumptions. Using PAPNET instead of conventional microscopy as a primary screening tool will make cervical cancer screening less cost-effective unless the costs of PAPNET are considerably reduced and its sensitivity and/or specificity are considerably improved.


Asunto(s)
Interpretación de Imagen Asistida por Computador , Prueba de Papanicolaou , Neoplasias del Cuello Uterino/patología , Frotis Vaginal/economía , Análisis Costo-Beneficio , Femenino , Humanos , Redes Neurales de la Computación , Sensibilidad y Especificidad , Factores de Tiempo , Neoplasias del Cuello Uterino/economía
9.
Br J Haematol ; 110(3): 647-53, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10997977

RESUMEN

In this study, we analysed the chimaeric status of peripheral blood leucocytes (PBLs) in recipients of allogeneic bone marrow transplantation (BMT) with the use of short tandem repeat (STR) microsatellite markers for monitoring the efficacy of BMT and donor leucocyte infusions (DLIs). A set of four STR markers was used with a highly discrimative capacity between individuals. STRs were detected by polymerase chain reaction (PCR) and were analysed by gene scanning (STR-GS). Between June 1990 and December 1998, 52 patients treated with BMT for chronic myeloid leukaemia (CML) were analysed. Seventeen patients relapsed after BMT and two patients never achieved remission after BMT. Fourteen of the 17 patients achieved a complete donor chimaerism after BMT, as detected by the presence of only donor STR-GS fragments, and in three cases a weak recipient STR-GS signal remained persistently detectable after BMT. A reappearance or increase of recipient STR-GS signals was indicative of relapse, which was mostly detected by STR-GS several months before relapse was diagnosed clinically. Nineteen patients were treated with DLI for reappearance of CML after BMT which resulted in complete remission in 17 patients, concordant with the disappearance of recipient STR-GS signals. More importantly, DLI treatment could be guided based upon the STR-GS data, which prevented unnecessary extra DLI courses that could cause toxicity. This study indicates that STR-GS is an effective and reliable method for monitoring BMT recipients.


Asunto(s)
Trasplante de Médula Ósea , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Transfusión de Leucocitos , Repeticiones de Microsatélite , Neoplasia Residual/diagnóstico , Adulto , Quimera , Femenino , Marcadores Genéticos , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Masculino , Recurrencia , Trasplante Homólogo
10.
Ned Tijdschr Geneeskd ; 143(47): 2345-7, 1999 Nov 20.
Artículo en Holandés | MEDLINE | ID: mdl-10590770

RESUMEN

Diagnosis is central to medicine. In spite of tremendous diagnostic technological advances, no infallible test exists and in the complex diagnostic process the physician may well get lost. The ultimate feedback on the accuracy of diagnosis is the autopsy. Five patients illustrate that the autopsy may disclose unexpected results. The first patient was a 9-year-old girl who suffered from daily abdominal spasmodic pain but each time recovered. She died suddenly; autopsy revealed intestinal intussusception. A 46-year-old man who was treated for hypertension developed pain in the chest and the lower back, but there were no other signs of myocardial infarction. He died suddenly; autopsy revealed a dissecting aortic aneurysm with rupture in the left pleural cavity. A 21-year-old woman, an excellent swimmer, drowned during a swim in the sea. Autopsy revealed severe widespread coronary disease with multiple myocardial infarction. A 32-year-old Surinam woman developed acute coma and died from cardiorespiratory arrest. At autopsy she had massive pulmonary embolism and generalized lymphadenopathy due to sarcoidosis. The last patient, a 32-year-old woman suffered from fatigue after her fourth child was born. She was admitted with severe dyspnoea and her chest X-ray showed interstitial fibrosis. She died presently and autopsy revealed metastatic colon carcinoma with pulmonary lymphangitis carcinomatosa. Systematic reviews of the results of autopsies show no decline in the percentage of false diagnoses and/or unexpected findings in spite of the enormous growth of the diagnostic armamentarium. Although we may radiologically 'slice' the body in incredible detail or investigate human cells at the molecular level, the autopsy has by no means become obsolete and is an invaluable tool for quality control and teaching.


Asunto(s)
Autopsia , Muerte Súbita/etiología , Errores Diagnósticos , Adenocarcinoma/complicaciones , Adenocarcinoma/diagnóstico , Adenocarcinoma/secundario , Adulto , Rotura de la Aorta/diagnóstico , Niño , Neoplasias del Colon/diagnóstico , Enfermedad Coronaria/diagnóstico , Resultado Fatal , Femenino , Humanos , Obstrucción Intestinal/complicaciones , Obstrucción Intestinal/diagnóstico , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Países Bajos , Embolia Pulmonar/diagnóstico , Sarcoidosis/complicaciones , Sarcoidosis/diagnóstico , Choque Séptico/diagnóstico
11.
Ned Tijdschr Geneeskd ; 143(47): 2351-4, 1999 Nov 20.
Artículo en Holandés | MEDLINE | ID: mdl-10590772

RESUMEN

The decreasing number of autopsies, in the Netherlands as well, is deplorable because with it an important instrument of medical quality control is likely to disappear. For this not only the relatives, but also the attending physicians and the pathologists are to blame. To turn the tide we need some drastic changes in our attitude towards autopsies. The families should known that an autopsy is a right they have in order to check the quality of diagnosis and treatment of their beloved, it is not a favour towards the physician. A physician who does not see a reason for autopsy, should explain that to the family. Pathologists should think about and realize a subspecialty of autopsy pathology with a thorough training in pathophysiology and intensive care medicine. Autopsy reports should be of the highest quality and reach the physician within a few weeks. A required autopsy percentage should be introduced into the certification process of medical specialists and hospitals and the possibility of Continuous Medical Education credit points for physicians with a certain autopsy percentage should be considered.


Asunto(s)
Autopsia/normas , Hospitales/normas , Patología/normas , Indicadores de Calidad de la Atención de Salud/normas , Autopsia/estadística & datos numéricos , Educación Médica Continua/normas , Humanos , Países Bajos , Patología/educación , Indicadores de Calidad de la Atención de Salud/estadística & datos numéricos
12.
Mod Pathol ; 12(11): 995-1000, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10574595

RESUMEN

OBJECTIVES: To assess computer-assisted (neural network based) cervical smear screening as a primary tool for the early detection of cervical dysplasia. DESIGN: Longitudinal cohort study. SETTING: Cytology laboratory reviewing cervical smears taken by general practitioners in a mass screening program in the Netherlands. SUBJECTS: 846 women who developed (pre-)neoplasia of the cervix in the seven years after the baseline smear, and 5217 controls. INTERVENTIONS: Cervical smears were evaluated both by conventional light microscopy and with use of the PAPNET Testing System by the same cytotechnologists. MAIN OUTCOME MEASURES: Seven year histological and cytological follow-up results were obtained for all women from a nation-wide pathology database. RESULTS: Conventional screening diagnosed dysplasia or carcinoma in the baseline smears of 458 (54.1%) of the 846 women who were diagnosed with (pre-)neoplasia during follow-up, whereas computer-assisted PAPNET analysis detected such lesions in 462 (54.6%) of these women. In the control population of 5217 (86.0%) women, in whom follow-up revealed no cervical dysplasia, conventional screening gave false positive results in 210 (4.0%) and computer-assisted PAPNET analysis gave false positive results in 207 (4.0%) smears. The areas under the receiver operation curves (AUC) were 80% (95% confidence interval, 78 to 82%) and 79% (95% confidence interval, 77 to 81%) for conventional and PAPNET-assisted screening, respectively. CONCLUSIONS: The PAPNET Testing System has similar diagnostic value as the conventional screening of Pap smears when used for primary screening.


Asunto(s)
Tamizaje Masivo/métodos , Redes Neurales de la Computación , Prueba de Papanicolaou , Displasia del Cuello del Útero/diagnóstico , Frotis Vaginal , Femenino , Humanos , Estudios Longitudinales , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/diagnóstico
13.
Cancer ; 87(4): 178-83, 1999 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-10455204

RESUMEN

BACKGROUND: To assess the interobserver and intraobserver variation of Papanicolaou (Pap) smear screening with the computer-assisted (neural network based) PAPNET Testing System in diagnosing cervical smear abnormalities, results of agreement were compared with the interobserver and intraobserver variation of conventional smear analysis. METHODS: Cervical smears obtained from women in 1996 were reevaluated both by conventional light microscopy and with use of the PAPNET Testing System by the same four investigators, and results were compared with the original screening diagnoses obtained by both methods. RESULTS: The interobserver results for epithelial abnormalities (the degree of agreement between the cytologists), characterized by weighted kappa statistics, were 0.71 (95% CI: 0. 68-0.73) for PAPNET screening and 0.69 (95% CI: 0.66-0.72) for conventional screening. No significant differences were found among the individual results obtained by the four cytotechnologists (intraobserver variation) with conventional screening versus PAPNET reviewing. CONCLUSIONS: Pap smear grading with the PAPNET Testing System has interobserver and intraobserver variation similar to that of conventional screening of Pap smears in routine use. Cancer (Cancer Cytopathol)


Asunto(s)
Interpretación de Imagen Asistida por Computador , Prueba de Papanicolaou , Displasia del Cuello del Útero/patología , Frotis Vaginal/instrumentación , Diagnóstico Diferencial , Femenino , Humanos , Tamizaje Masivo/métodos , Redes Neurales de la Computación , Variaciones Dependientes del Observador , Neoplasias del Cuello Uterino/patología , Frotis Vaginal/métodos , Frotis Vaginal/estadística & datos numéricos
14.
J Low Genit Tract Dis ; 2(1): 19-24, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25951358

RESUMEN

To increase the sensitivity of the cervical Papanicolaou (Pap) smear, several automated devices now are commercially available. In the last 2 years, the U.S. Food and Drug Administration approved three of these devices, each of which operates differently from the others. The ThinPrep 2000 is a method whereby the traditional Pap smear is substituted by a liquid-based smear collection technique that allows the preparation of thin layers, which addresses the problems of obscuring blood, inflammation, and overlapping cells on traditional smears. The AutoPap 300 QC is a rescreening device that selects from a batch of negative smears the 10% most likely abnormal smears for manual rescreening. The PAPNET Testing System is a neural network-based semiautomated screening system used for adjunctive testing of negative Pap smears. The system selects and displays the most abnormal-looking cells for review by the cytotechnologist, thus improving the detection of missed abnormalities. The effectiveness of the introduction of these devices for cervical cancer detection is discussed.

15.
Cytopathology ; 8(5): 313-21, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9313983

RESUMEN

We have compared the results of targeted manual rescreening of 1211 randomly selected smears with the results of PAPNET-assisted rescreening of 1613 cervical smears, containing at least 6.3% low-grade squamous intraepithelial lesion (SIL). PAPNET diagnosis and the targeted rescreening diagnosis were compared with the initial report, issued on the corresponding smear. Reproducibility scores for inadequacy, presence of endocervical and endometrial cells, specific infections and squamous cell abnormalities were determined. The reproducibility scores for the diagnosis of inadequate smears and specific infections were lower with the PAPNET-assisted rescreening. The detection of squamous cell abnormalities was excellent for both methods (> 0.95), with a higher detection rate for false-negative smears with the PAPNET testing system.


Asunto(s)
Diagnóstico por Computador , Neoplasias del Cuello Uterino/prevención & control , Frotis Vaginal , Femenino , Técnicas de Preparación Histocitológica , Humanos , Reproducibilidad de los Resultados , Neoplasias del Cuello Uterino/patología
16.
Exp Cell Res ; 234(2): 521-6, 1997 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-9260923

RESUMEN

NIH-3T3 fibroblasts expressing epidermal growth factor receptors (EGFRs) lacking the actin binding domain (ABD) were analyzed for their EGF-induced capacity to invade a bone marrow stromal cell (BMSC) monolayer. The fibroblasts display a reduction in the percentage of cytoskeleton-associated EGFRs. Furthermore, EGF-induced tyrosine kinase activity is unaffected by the mutation. Cells expressing the mutant EGFRs hardly invade a BMSC monolayer upon EGF stimulation in contrast to cells expressing wild-type EGFRs. Using the same cells no difference was observed in PDGF-induced invasion, which ligand was as potent in both cell types as EGF was in wild-type cells. Inhibition of both the phosphatidyl inositol-3-kinase (PI-3-K) and lipoxygenase pathways in wild-type cells mimicked the effect of the ABD deletion. Our results point to an important role for the ABD of the EGFR in EGF-induced tissue invasion.


Asunto(s)
Actinas/metabolismo , Células de la Médula Ósea , Movimiento Celular/fisiología , Factor de Crecimiento Epidérmico/farmacología , Receptores ErbB/metabolismo , Células 3T3 , Androstadienos/farmacología , Animales , Sitios de Unión , Adhesión Celular/fisiología , Células Cultivadas , Técnicas de Cocultivo , Citoesqueleto/metabolismo , Inhibidores Enzimáticos/farmacología , Receptores ErbB/genética , Humanos , Inhibidores de la Lipooxigenasa/farmacología , Masoprocol/farmacología , Ratones , Invasividad Neoplásica , Fosfatidilinositol 3-Quinasas , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Fosfotransferasas (Aceptor de Grupo Alcohol)/fisiología , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteínas Tirosina Quinasas/metabolismo , Transducción de Señal/fisiología , Wortmanina
17.
Int J Cancer ; 72(4): 637-41, 1997 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-9259404

RESUMEN

Many patients with exocrine pancreatic cancer develop diabetes mellitus due to insulin resistance. This may relate to concurrent over-production of islet amyloid polypeptide (IAPP) by the pancreatic beta cells. We investigated the effects of pancreatic cancer on circulating IAPP and glucose homeostasis in azaserine-treated rats (developing acinar pancreatic tumours) and BOP-treated hamsters (developing ductular pancreatic tumours). Glucose, insulin and IAPP levels in plasma were neither affected in azaserine-only treated rats nor in animals with enhanced carcinogenesis after chronic caerulein treatment. Azaserine-treated rats on a high-fat diet had decreased insulin levels and enhanced IAPP/insulin ratios in plasma, without hyperglycaemia. All BOP-treated hamsters showed pancreatic carcinogenesis at 6 months post-treatment. Supranormal plasma glucose levels in animals on a low-fat diet were the only change observed. After a second 6-month period, subnormal plasma glucose levels, at least 4-fold decreased plasma insulin and up to 2-fold decreased plasma IAPP levels were present in all hamsters. Remarkably, both in azaserine-treated rats on high-fat and in BOP-treated hamsters, decreased insulin levels and elevated IAPP/insulin ratios are not associated with hyperglycaemia. In contrast to humans with pancreatic cancer, IAPP over-production and hyperglycaemia do not develop in rats and hamsters with (pre-)neoplastic pancreatic lesions.


Asunto(s)
Amiloide/sangre , Hiperglucemia/sangre , Hiperglucemia/etiología , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/complicaciones , Lesiones Precancerosas/sangre , Animales , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Carcinógenos , Cricetinae , Grasas de la Dieta/efectos adversos , Modelos Animales de Enfermedad , Homeostasis , Insulina/sangre , Polipéptido Amiloide de los Islotes Pancreáticos , Masculino , Mesocricetus , Tamaño de los Órganos/efectos de los fármacos , Páncreas/anatomía & histología , Páncreas/efectos de los fármacos , Neoplasias Pancreáticas/inducido químicamente , Lesiones Precancerosas/inducido químicamente , Ratas , Ratas Wistar
18.
Cancer ; 79(8): 1548-51, 1997 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-9118037

RESUMEN

BACKGROUND: Hypoplastic myelodysplastic syndrome (MDS) is characterized by dysplasia and hypocellularity. The treatment of choice for young patients is bone marrow transplantation. METHODS: This report describes the effect of immunosuppressive therapy in two patients with hypoplastic MDS for whom no suitable bone marrow donors were available. RESULTS: Both patients had no human lymphocyte antigen-identical siblings and no suitable matched unrelated donor could be found. They received cyclosporin A (CsA), antithymocyte globulin (ATG), or a combination of the two. Treatment with CsA, ATG, or the combination led to clinical improvement (resolution of transfusion requirement), increase of bone marrow cellularity, and the disappearance of dysplastic characteristics in the two patients with hypoplastic MDS. At the time of recurrence, this disease was still responsive to immunosuppressive therapy. CONCLUSIONS: Treatment with ATG and CsA can be an attractive alternative for patients with hypoplastic MDS for whom there is no possibility of bone marrow transplantation.


Asunto(s)
Suero Antilinfocítico/uso terapéutico , Ciclosporina/uso terapéutico , Inmunosupresores/uso terapéutico , Síndromes Mielodisplásicos/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/sangre , Prednisona/uso terapéutico
19.
Eur J Radiol ; 24(2): 120-3, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9097053

RESUMEN

OBJECTIVE: To assess the accuracy of large-core needle biopsy in evaluating palpable and nonpalpable breast lesions. METHODS AND PATIENTS: Stereotaxic and ultrasound (US) guided core biopsies were performed in 103 breast lesions in 97 patients. Subsequently, all patients underwent surgery. All specimens (core biopsy and surgical) underwent radiography for evaluation of microcalcifications. The histopathologic findings of the core biopsies and the surgical specimens were correlated. RESULTS: Core biopsies and surgery findings were concordant in 100% of the 27 palpable lesions and in 89% of the 76 nonpalpable lesions. One case of malignancy, ductal carcinoma in situ (DCIS), was not diagnosed by core biopsy. In 102 (99%) of the 103 breast lesions, a correct choice for additional diagnostic procedure or definitive treatment could have been made upon histopathologic findings of core biopsy. CONCLUSION: Stereotaxic and ultrasound-guided core biopsy are safe, reliable and less traumatic than excisional biopsy. Special attention is necessary when atypical ductal hyperplasia (ADH) or DCIS without invasive carcinoma is found. Radiography of the biopsy specimens for detection of microcalcifications is essential.


Asunto(s)
Biopsia con Aguja , Neoplasias de la Mama/patología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia/métodos , Mama/patología , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Calcinosis/diagnóstico por imagen , Calcinosis/patología , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/patología , Carcinoma Lobular/diagnóstico , Carcinoma Lobular/patología , Femenino , Enfermedad Fibroquística de la Mama/diagnóstico , Enfermedad Fibroquística de la Mama/patología , Humanos , Hiperplasia , Persona de Mediana Edad , Palpación , Radiografía , Reproducibilidad de los Resultados , Seguridad , Técnicas Estereotáxicas , Ultrasonografía Mamaria
20.
Exp Cell Res ; 230(1): 111-20, 1997 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-9013713

RESUMEN

Tumor cell interactions with fibronectin (FN) are important for the development of secondary tumors inside the bone marrow stroma. We studied and compared the in situ distribution of FN in paraffin-embedded human bone marrow sections and investigated the in vitro regulation of FN assemblage by bone marrow stromal cells (BMSC). Finally, the role of FN in the interaction of BMSC with tumor cells was studied. Fine elongated FN-positive cell extensions, probably of stromal cell origin, were observed as well as a limited amount of extracellular FN deposits in connective tissues around capillaries and sinusoids. In vitro studies, using the confocal laser scanning microscope, showed that BMSC produced a high amount of FN with a characteristic extracellular matrix formation in an extensive network. FN matrix formation was predominantly detected at contact sites between cultured BMSC. In in vitro cultures with low cell concentrations and in vivo with a limited number of stromal cell contacts only limited matrix was found. From previous studies it is known that the alpha5 beta1 integrin is involved in the regulation of FN assembly. Here the role of the alpha5-subunit of this integrin was investigated. By using two different monoclonal antibodies (mAb) against the alpha5-subunit (2H6 and mAb16) the assembly of endogenous FN was completely blocked, indicating that these antibodies are directed against the active epitope. Another mAb (mAb11) against the alpha5-subunit did not affect the FN assemblage. Codistribution analysis of alpha5-subunits, alpha v-subunits, actin, and FN demonstrated that the alpha5 beta1 integrin is associated with FN and not with intracellular actin. Integrins alpha(v) beta1, alpha(v) beta3, and alpha(v) beta5, also ligands of FN, did not colocalize with FN. Codistribution of alpha v with the terminal ends of actin and not with FN indicates that alpha(v)-subunits are mainly directed to vitronectin rather than to FN. The dominant role of alpha5 beta1 in FN interaction is underlined by effective blocking of tumor cell adhesion with BMSC using anti-alpha5, anti-beta1, and anti-FN antibodies. These results emphasize the important role of alpha5 integrin subunit in FN matrix assembly in human BMSC and an exclusive role of alpha5 beta1 in the anchorage and regulation of FN-mediated adhesion processes in the bone marrow.


Asunto(s)
Médula Ósea/metabolismo , Fibronectinas/metabolismo , Receptores de Fibronectina/metabolismo , Actinas/metabolismo , Células de la Médula Ósea , Adhesión Celular/fisiología , Matriz Extracelular/metabolismo , Humanos , Inmunohistoquímica , Técnicas In Vitro , Masculino , Células Tumorales Cultivadas
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