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1.
BMC Womens Health ; 22(1): 506, 2022 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-36482357

RESUMEN

BACKGROUND: Reproductive decision-making is difficult for BRCA-positive women. Our objective was to assess the complexities of decision-making and identify decisional supports for patients and providers when discussing reproductive options prior to risk-reducing salpingo-oophorectomy (RRSO). METHODS: This study was of qualitive design, using data collection via semi-structured interviews conducted from November 2018 to October 2020. Individuals were included if they were identified to provide care to BRCA-positive women. In total, 19 providers were approached and 15 consented to participate. Providers were recruited from three clinics in Toronto, Ontario located at academic centers: [1] A familial ovarian cancer clinic, [2] A familial breast cancer clinic and [3] A fertility clinic, all of which treat carriers of the BRCA1/BRCA2 genetic mutation. The interview guide was developed according to the Ottawa Decision Support Framework and included questions regarding reproductive options available to patients, factors that impact the decision-making process and the role of decisional support. Interviews were transcribed and transcripts were analyzed thematically using NVIVO 12. RESULTS: Providers identified three major decisions that reproductive-aged women face when a BRCA mutation is discovered: [1] "Do I want children?"; [2] "Do I want to take the chance of passing on this the mutation?"; and [3] "Do I want to carry a child?" Inherent decision challenges that are faced by both providers and patients included difficult decision type, competing options, scientifically uncertain outcomes, and challenging decision timing. Modifiable decisional needs included: inadequate knowledge, unrealistic expectations, unclear values and inadequate support or resources. Identified clinical gaps included counselling time constraints, lack of reliable sources of background information for patients or providers and need for time-sensitive, geographically accessible, and centralized care. CONCLUSION: Our study identified a need for a patient information resource that can be immediately provided to patients who carry a BRCA genetic mutation. Other suggestions for clinical practice include more time during consultation appointments, adequate follow-up, value-centric counseling, access to psychosocial support, and a specialized decisional coach.


Asunto(s)
Niño , Humanos , Femenino , Adulto , Ontario
2.
Am J Phys Anthropol ; 156(4): 543-52, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25594359

RESUMEN

The midtarsal break was once treated as a dichotomous, non-overlapping trait present in the foot of non-human primates and absent in humans. Recent work indicates that there is considerable variation in human midfoot dorsiflexion, with some overlap with the ape foot. These findings have called into question the uniqueness of the human lateral midfoot, and the use of osteological features in fossil hominins to characterize the midfoot of our extinct ancestors. Here, we present data on plantar pressure and pedal mechanics in a large sample of adults and children (n = 671) to test functional hypotheses concerning variation in midfoot flexibility. Lateral midfoot peak plantar pressure correlates with both sagittal plane flexion at the lateral tarsometatarsal joint, and dorsiflexion at the hallucal metatarsophalangeal joint. The latter finding suggests that midfoot laxity may compromise hallucal propulsion. Multiple regression statistics indicate that a low arch and pronation of the foot explain 40% of variation in midfoot peak plantar pressure, independent of age and BMI. MRI scans on a small subset of study participants (n = 19) reveals that curvature of the base of the 4th metatarsal correlates with lateral midfoot plantar pressure and that specific anatomies of foot bones do indeed reflect relative midfoot flexibility. However, while the shape of the base of the 4th metatarsal may reliably reflect midfoot mobility in individual hominins, given the wide range of overlapping variation in midfoot flexibility in both apes and humans, we caution against generalizing foot function in extinct hominin species until larger fossils samples are available.


Asunto(s)
Pie/anatomía & histología , Pie/fisiología , Huesos Metatarsianos/anatomía & histología , Huesos Metatarsianos/fisiología , Animales , Hominidae/anatomía & histología , Hominidae/fisiología , Humanos , Modelos Lineales , Paleontología , Caminata/fisiología
3.
J Thromb Haemost ; 9(12): 2486-97, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21981655

RESUMEN

BACKGROUND: Severe preeclampsia is characterized by hypertension, renal injury and placental dysfunction. Prothrombotic disorders are discovered in 10-20% of women with preeclampsia, providing the rationale for prescribing low-molecular-weight heparin (LMWH) in future pregnancies. Heparin has diverse molecular actions and appears to reduce the recurrence risk of preeclampsia in women without prothrombotic disorders. The placenta-derived anti-angiogenic splice-variant protein soluble vascular endothelial growth factor (VEGF) receptor-1 (sFLT1) is strongly implicated in the pathogenesis of the underlying endothelial dysfunction. As the placental syncytiotrophoblast is the principal source of sFLT1, we tested the hypothesis that heparin suppresses placental sFLT1 secretion. METHODS AND RESULTS: First trimester placental villi exposed to LMWH (0.25-25 IU mL(-1)) in an in vitro explant model significantly increased the expression and release of sFLT1 by the syncytiotrophoblast into culture media, reducing phosphorylation of FLT1 and KDR receptors in cultured human umbilical vein endothelial cells. This response was significantly diminished in placental villi from healthy term pregnancies. Placental villi from severely preeclamptic pregnancies had a higher baseline sFLT1 release, compared with first trimester placental villi and did not respond to LMWH treatment. LMWH promoted villous cytotrophoblast proliferation (BrdU incorporation) and impaired syncytial fusion-differentiation, causing syncytiotrophoblast apoptosis (by caspase 3&7 activity and TUNEL staining) and necrosis (ADP/ATP ratio). CONCLUSION: LMWH promotes sFLT1 synthesis and release from first trimester placental villi in a manner similar to that of severely preeclamptic placental villi, which antagonizes VEGF signaling in endothelial cells. These effects in part are mediated by an interaction between heparin and the cytotrophoblasts that regenerates the overlying syncytiotrophoblast responsible for sFLT1 secretion into the maternal blood.


Asunto(s)
Vellosidades Coriónicas/efectos de los fármacos , Endotelio Vascular/metabolismo , Heparina de Bajo-Peso-Molecular/farmacología , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adulto , Secuencia de Bases , Vellosidades Coriónicas/metabolismo , Cartilla de ADN , Femenino , Humanos , Fosforilación , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
J Vasc Surg ; 33(3): 587-94, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11241131

RESUMEN

PURPOSE: Heparin binds to human platelets and can cause activation and aggregation, although the mechanisms are unknown. To determine how heparin alters platelet function, we identified platelet-binding sites for heparin and measured heparin's influence on the function of platelet integrin alpha(IIb)beta(3) (glycoprotein IIb/IIIa). METHODS: Photoaffinity cross-linking and affinity chromatography experiments were performed to identify platelet membrane proteins that bind heparin. Heparin's effect on fibrinogen binding to platelets was measured with a radioligand-binding assay. The translocation to the cytoskeleton of Rap2, a guanosine triphosphate-binding protein, was measured from platelets aggregating in response to heparin and other agonists. RESULTS: Cross-linking and affinity chromatographic experiments positively identified the integrin alpha(IIb)beta(3) as a heparin-binding site. Heparin aggregation was calcium dependent. Low concentrations of unfractionated porcine mucosal heparin (2-5 U/mL) significantly increased fibrinogen I 125 binding to activated platelets, whereas higher doses did not. Heparin-mediated platelet aggregation was completely blocked by GRGDS peptide (5 mmol/L), a competitive inhibitor of fibrinogen binding, and was blocked by EDTA (2 mmol/L), which dissociates the functional integrin complex. Aggregation was associated with Rap2 translocation to the cytoskeleton, a sign of outside-in signaling. CONCLUSIONS: Heparin binds to the alpha(IIb)beta(3) integrin in vitro and ex vivo, and heparin increases fibrinogen binding to the integrin. Heparin-mediated aggregation requires an intact integrin and ligand and leads to Rap2 translocation to the cytoskeleton-an outside-in signal of ligand engagement. Heparin may directly modulate platelet integrin function, most likely through direct binding and modulation of integrin function.


Asunto(s)
Plaquetas/efectos de los fármacos , Heparina/farmacología , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Sitios de Unión , Células Cultivadas , Fibrinógeno/metabolismo , Humanos , Receptores de Superficie Celular/metabolismo
5.
Ann Diagn Pathol ; 4(3): 135-42, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10919382

RESUMEN

Alveolar soft part sarcoma (ASPS) is a rare malignant neoplasm characterized by slow growth and indolent behavior. The role of proliferative markers and tumor suppressor genes is unknown in these tumors. To investigate their potential role in diagnosis and prognosis, we studied 13 cases of primary ASPS and 14 metastases and correlated them with clinicopathologic parameters. Immunohistochemistry was performed with anti-p53 and anti-Ki-67 antibodies. Polymerase chain reaction after tumor microdissection was performed to search for possible loss of heterozygosity in chromosomes 1p, 9p, 17q, 22q, and TP53 to identify possible changes that may clarify the histogenesis of these tumors. Four of five (80%) primary ASPS cases were positive for Ki-67 and all of them developed later metastases. One patient whose tumor did not stain for Ki-67 remained free of disease for 9 years. Eleven of 13 (85%) metastases were positive for Ki-67; however, there was no correlation with final outcome. All the primary ASPS cases analyzed for p53 yielded negative results, but two (15%) of 13 metastases were weakly positive. There was no correlation of these markers with prognosis or clinicopathologic parameters. No loss of heterozygosity was found except in one of nine (11%) informative metastases for D1S165 (at 1p36). Our preliminary data suggest that Ki-67-positive immunostaining may be a prognostic indicator for the development of metastases in ASPS.


Asunto(s)
Biomarcadores de Tumor/análisis , Sarcoma de Parte Blanda Alveolar/metabolismo , Adolescente , Adulto , Niño , Femenino , Genes p53 , Humanos , Inmunohistoquímica , Antígeno Ki-67/análisis , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Pronóstico , Sarcoma de Parte Blanda Alveolar/genética , Sarcoma de Parte Blanda Alveolar/secundario , Proteína p53 Supresora de Tumor/análisis , Proteína p53 Supresora de Tumor/genética
6.
Hum Pathol ; 31(2): 233-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10685639

RESUMEN

Loss of heterozygosity (LOH) of tumor suppressor genes (TSGs) in ovarian epithelial tumors of differing cell types and biological behavior has not been thoroughly investigated. Moreover, there have been conflicting reports correlating LOH of the p53 gene to overexpression of p53 protein. This study evaluated 34 formalin-fixed, paraffin-embedded ovarian epithelial tumors for LOH by polymerase chain reaction (PCR) for the following microsatellite markers: TP53(17p13.1/p53 gene), D17S579(17q/BRCA1 gene), and ESR (6q24-27/estrogen receptor gene). LOH of the TP53 marker was detected in 4 (44%) of 9 informative serous cystadenocarcinomas (SCa) but in 0 of 4 informative clear cell carcinomas (CCa) and 0 of 5 informative serous tumors of low malignant potential (SLMP). LOH of the BRCA1 marker was detected in 5 (83%) of 6 informative SCa, but in 1 (13%) of 8 informative CCa and 1 (14%) of 7 informative SLMP. LOH of the ESR marker was detected in 4 (50%) of 8 informative SCa, but in 0 of 4 informative CCa and 1 (16%) of 6 informative SLMP. p53 protein overexpression was present in 8 of 12 SCa but did not correlate to TP53 LOH. LOH for TP53, D17S579/ BRCA1, and ESR is common in ovarian SCa, and is observed in primary tumors as well as metastases. In contrast, these genetic alterations are less common in CCa and in the biologically less aggressive SLMP tumors. These data suggest different mechanisms of oncogenesis in ovarian epithelial tumors of different cell types and biological behavior.


Asunto(s)
Proteína BRCA1/genética , Expresión Génica , Genes p53 , Pérdida de Heterocigocidad , Neoplasias Ováricas/genética , Receptores de Estrógenos/genética , Adenocarcinoma de Células Claras/genética , Cistadenocarcinoma Seroso/genética , Femenino , Humanos , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa
8.
Endod Dent Traumatol ; 16(3): 128-31, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11202869

RESUMEN

Just as gutta-percha used with a root canal sealer is a recommended material for orthograde root fillings, it could similarly be the material of choice for retrograde fillings. Unfortunately, clinical accessibility and visibility do not always facilitate such a technique. The aim of this article is to present a new technique which enables retrograde fillings to be achieved with gutta-percha and a sealer. After the apex had been resected, a hole was drilled perpendicular to the plane of section of the apex about 1 mm coronally. The bucco-lingual depth required to reach the main canal was calculated. The cavity was then dried, coated with the sealer, and obturated with gutta-percha in accordance with thermo-mechanical compaction techniques. After excess filling material had been removed, the gutta-percha was cold burnished and the angles of the root were smoothed. Clinical cases illustrating healing of the periapical tissues are shown.


Asunto(s)
Gutapercha/uso terapéutico , Obturación Retrógrada/métodos , Materiales de Obturación del Conducto Radicular/uso terapéutico , Apicectomía , Pulido Dental , Dentadura Parcial Fija , Estudios de Seguimiento , Calor , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Periapicales/terapia , Obturación Retrógrada/instrumentación , Estrés Mecánico , Raíz del Diente/cirugía , Cicatrización de Heridas
9.
J Endod ; 26(4): 242-4, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11199728

RESUMEN

Endodontic treatments may give rise to persistent pain whose origin is sometimes difficult to determine. Although it is unusual, pain may occur due to apical fenestrations following endodontic treatment. If this occurs, the solution is surgical intervention. This surgical procedure consists of raising a flap to expose the fenestration, followed by curettage of any overextended canal filling materials that may be potentially irritating to the underlying mucosa, remodeling of the apex, and its repositioning below the level of the cortical bone. A case is described that illustrates this clinical situation. The case also demonstrates information that can be obtained from tomodensitometric films.


Asunto(s)
Enfermedades Maxilares/complicaciones , Obturación del Conducto Radicular/efectos adversos , Ápice del Diente/patología , Odontalgia/etiología , Apicectomía , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Gutapercha/efectos adversos , Humanos , Persona de Mediana Edad , Materiales de Obturación del Conducto Radicular/efectos adversos , Tomografía Computarizada por Rayos X
10.
Breast Cancer Res ; 2(4): 237-40, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11250713

RESUMEN

The use of human tissue, and material derived from such tissue, for research purposes is currently the subject of much debate. This debate needs to address several issues, including: the principle of abandonment; the distinction between identified and unidentified specimens; general versus specific informed consent; and, with the improvement in biotechnology and medical informatics, the design and security of research databases. The outcome of this debate will shape the way in which research studies using human biological materials are designed and executed.


Asunto(s)
Neoplasias de la Mama/patología , Propiedad/legislación & jurisprudencia , Defensa del Paciente/legislación & jurisprudencia , Investigación/legislación & jurisprudencia , Técnicas de Cultivo de Célula , Confidencialidad , Técnicas de Cultivo , Femenino , Control de Formularios y Registros , Humanos , Consentimiento Informado , Opinión Pública , Proyectos de Investigación , Apoyo a la Investigación como Asunto , Conservación de Tejido , Células Tumorales Cultivadas , Reino Unido , Estados Unidos
11.
Curr Pharm Des ; 5(12): 965-86, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10607857

RESUMEN

Heparin, a complex glycosaminoglycan, has long been used to temporarily render the blood incoagulable during extracorporeal circulation, cardiovascular surgery, and other arterial interventions. But bleeding complications are especially common when the arterial tree is violated, occurring in as many as 10-15% of cases. For cardiovascular surgery and many related interventions, protamine has long been the standard antagonist when acute and complete neutralization of heparin s anticoagulant effect is necessary. Protamine s efficacy is related in part to its total net cationic charge, but unfortunately so is its toxicity. For these reasons, there is renewed interest in developing heparin antagonists which will replace the use of protamine. At Commonwealth Biotechnologies, Inc., we have used a rationale design approach for the preparation of a family of low molecular weight helix peptides which bind heparin with high affinity. For each of the new compounds, we have assessed their ability to bind heparin using isothermal titration calorimetry and circular dichroism spectrometry and have examined potential complexes formed with the anticoagulant pentasaccharide unit of heparin using molecular modeling techniques. The biological potencies of these compounds were assessed in ex vivo experiments where their ability to compete with antithrombin for binding heparin was determined. The best of the compounds, designated HepArrestTM, is highly effective in reversing heparin-mediated and HepArrest is a safer drug than protamine because of reduced adverse hemodynamic side effects compared with those associated with protamine. HepArrest binds low molecular weight heparins and causes reversal of anticoagulation by low molecular weight heparins, as determined by activated partial thromboplastin time, thrombin time, or factor Xa neutralization assays. These highly promising preclinical results indicate that HepArrest is a novel heparin neutralizing agent that may well fill a substantial unmet need for vascular surgeons and cardiac anesthesiologists who perform coronary artery bypass grafts and several other major vascular surgeries, as well as for cardiologists and interventional radiologists.


Asunto(s)
Coagulantes/farmacología , Antagonistas de Heparina/farmacología , Péptidos/síntesis química , Animales , Ensayos Clínicos como Asunto , Perros , Diseño de Fármacos , Cobayas , Heparina/metabolismo , Humanos , Técnicas In Vitro , Estructura Molecular , Péptidos/farmacología , Protaminas/uso terapéutico , Porcinos , Factores de Tiempo
12.
Pathol Res Pract ; 195(10): 677-80, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10549031

RESUMEN

Lung cancer is the leading cause of death in both women and men in the United States and many European countries. Molecular cytogenetic and LOH analyses of non-small cell lung cancer have shown somatic genetic alterations in a variety of chromosomes, such as 1p, 3p, 5q, 8p, 9p, 11p, 11q and 17p. Allelic deletions of the known tumor suppressor gene APC at 5q21 are frequently observed in advanced stages of lung cancer and have been correlated with poor prognosis in previous reports. We investigated 33 cases of NSCL for LOH at 5q21: 22 squamous cell and 11 adenocarcinomas. Normal and tumor cells were microdissected from paraffin embedded tissues and PCR amplification was performed utilising the specific markers D5S299 and D5S346 at 5q21 and PYGM at 11q13, respectively. Clinicopathological data, survival and recurrence rates were obtained in all cases. We detected LOH at 5q21 in 4/9 (44%) informative adenocarcinomas and in 13/16 (81%) informative SCC. LOH was frequent in early stages (12/15 stage I cases) and did not correlate with recurrence or poor survival. Our results show that LOH at 5q21 is more frequent in squamous cell carcinomas than in adenocarcinomas, is frequent in early stages of the disease, and does not have prognostic significance.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Cromosomas Humanos Par 5/genética , Proteínas del Citoesqueleto/genética , Pérdida de Heterocigocidad/genética , Neoplasias Pulmonares/genética , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Proteína de la Poliposis Adenomatosa del Colon , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidad , Femenino , Marcadores Genéticos , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Supervivencia
13.
Bioorg Med Chem Lett ; 9(21): 3127-32, 1999 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-10560738

RESUMEN

A synthetic pentasaccharide corresponding to the antithrombin III-binding region in heparin was also found to bind to human platelets. To identify the platelet-binding site in the pentasaccharide which is expected to be a novel sequence in heparin responsible for its platelet-binding, five partial structures of this particular pentasaccharide were synthesized. In a competitive assay using [3H]-heparin, a trisaccharide, O-(2-deoxy-2-sulfamido-3,6-di-O-sulfo-alpha-D-glucopyranosyl)-1--> 4)-O-(2-O-sulfo-alpha-L-idopyranosyluronic acid)-(1-->4)-2-deoxy-2-sulfamido-6-O-sulfo-alpha-D-glucopyranose, was concluded to be a high-affinity site for heparin's binding to platelets.


Asunto(s)
Plaquetas/química , Heparina/química , Oligosacáridos/síntesis química , Antitrombina III/química , Sitios de Unión , Unión Competitiva , Conformación de Carbohidratos , Secuencia de Carbohidratos , Heparina/farmacología , Humanos , Datos de Secuencia Molecular , Estructura Molecular , Oligosacáridos/farmacología , Unión Proteica
14.
Int Endod J ; 32(3): 225-8, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10530211

RESUMEN

CLINICAL TECHNIQUE: Effective apical sealing in endodontic surgery requires a dry root-end cavity to insert the filling material. A number of procedures for controlling haemorrhage have been described in the literature. An improvement of these techniques is proposed in this paper: by using a mixture of surgical wax and fibres of calcium alginate. This device, easy to place, sterile and non-toxic, permits placement of a root-end filling under more favourable conditions.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Técnicas Hemostáticas , Hemorragia Bucal/prevención & control , Tejido Periapical/cirugía , Obturación Retrógrada/métodos , Alginatos/uso terapéutico , Humanos , Hemorragia Bucal/etiología , Procedimientos Quirúrgicos Orales/efectos adversos , Obturación Retrógrada/efectos adversos , Ceras/uso terapéutico
15.
Arch Pathol Lab Med ; 123(11): 1076-8, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10539912

RESUMEN

Recent advances in molecular pathology and molecular genetics have created new concerns about the use of human biologic materials in research. Since researchers now have the ability to extract and amplify DNA from minuscule archived samples, virtually any human tissue sample can potentially become the template for a test that provides information that may relate to the inherited genes of an individual. Researchers using human biologic materials should follow the 3 basic principles that have been defined for all ethical human subjects research: respect for persons, beneficence, and justice. Institutional Review Boards are responsible for providing review of the risks and benefits of research proposals to safeguard the rights and welfare of human subjects. Currently, there is considerable debate concerning the role of informed consent procedures and the Institutional Review Board oversight process in situations when researchers use human biologic materials that have been anonymized or coded. In 1999, the National Bioethics Advisory Commission is expected to make recommendations to President Clinton and the National Science and Technology Council that are expected to clarify the balance between respect for personal autonomy and the societal need to pursue biomedical research to improve the health and welfare of all individuals.


Asunto(s)
Ética Médica , Técnicas Genéticas , Patología Clínica , Experimentación Humana/legislación & jurisprudencia , Humanos , Consentimiento Informado , Estados Unidos
16.
Int J Gynecol Pathol ; 18(4): 320-4, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10542939

RESUMEN

The association of endometrial carcinoma with other gynecologic neoplasms, especially ovarian and fallopian tube carcinoma, has been well documented and is usually interpreted as a result of a field defect. Sporadic synchronous primary carcinomas occurring in the endometrium and colon are extremely rare, especially in the absence of the familial genetic abnormalities seen in hereditary nonpolyposis colorectal carcinoma (HNPCC) syndrome, and may present a diagnostic dilemma. Two cases of synchronous adenocarcinomas of the endometrium and colon were studied for genetic abnormalities and differences to test for the presence of two primary tumors. Primary tumors, metastases, and normal tissues were microdissected from formalin-fixed, paraffin-embedded tissues. PCR amplification was performed for microsatellite DNA markers on chromosome 17q and 11q13. The colonic tumors were moderately and poorly differentiated, invasive, nonmucinous adenocarcinomas, whereas one uterine tumor was endometrioid adenocarcinoma and the other was papillary serous carcinoma. Although microsatellite instability, as evidenced by changes in the lengths of the amplified PCR products, was detected at 17q and 11q13 loci in the uterine and colonic neoplasms, the patterns of instability differed between the two primary tumor sites. Moreover, the lymph node metastasis in one colonic tumor had genetic alterations that differed from that of the primary tumor. In both patients, the molecular studies suggested the presence of two synchronous primary tumors. Molecular techniques may assist in distinguishing two separate primaries by determining the contraction and expansion of microsatellite regions in DNA obtained by microdissection from the primary tumors and associated metastases.


Asunto(s)
Adenocarcinoma/genética , Neoplasias del Colon/genética , Neoplasias Endometriales/genética , Repeticiones de Microsatélite/genética , Neoplasias Primarias Múltiples/genética , Adenocarcinoma/diagnóstico , Anciano , Anciano de 80 o más Años , Alelos , Autorradiografía , Neoplasias del Colon/diagnóstico , Diagnóstico Diferencial , Electroforesis en Gel de Poliacrilamida , Neoplasias Endometriales/diagnóstico , Femenino , Humanos , Neoplasias Primarias Múltiples/diagnóstico , Reacción en Cadena de la Polimerasa
18.
Cancer ; 87(4): 238-42, 1999 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-10455213

RESUMEN

BACKGROUND: The Tall cell variant of papillary carcinoma of the thyroid (TCV) is characterized by the proliferation of oxyphilic, tall, columnar cells with a height-to-width ratio of at least 2:1. TCV exhibits more aggressive clinical behavior than conventional thyroid papillary carcinoma (CPC). Cytologic features suggestive of TCV have been described in fine-needle aspiration material from primary tumors. Similarly, loss of heterozygosity (LOH) for chromosome 1 (D1S243) and the p53 gene (TP53) have been reported in TCV but not in CPC, thus making exploitation of this genetic feature a potential tool for molecular discrimination between these two neoplasms. METHODS: Cytology samples of metastatic and/or recurrent neoplasms (M/R) (12 cases) and 7 cases of primary TCV obtained from 12 patients were evaluated. The cytologic findings of these cases were compared with previously published findings. Microdissection and polymerase chain reaction for LOH for chromosome 1 and p53 (D1S243 and TP53 markers) were performed on cytologic smears from 6 cases of M/R tumors and 3 cases of primary tumors. RESULTS: More then 50% of M/R showed atypical follicular cells with enlarged nuclei, granular chromatin, nuclear grooves, pseudoinclusions, and abundant finely granular cytoplasm. Cells were disposed in monolayers (58%) and papillary clusters (50%). Similar findings were present in cases of primary TCV. LOH studies showed that 4 of 6 M/R were noninformative and 2 of 3 cases of primary TCV were informative for the D1S243 marker; however, in contrast with previously published reports, no LOH was detected for the markers evaluated. CONCLUSIONS: M/R and primary TCV have similar cytologic features. Additional studies of larger series of M/R and primary TCV should be performed to delineate further any potential application of LOH for chromosome 1 and the p53 gene as a tool for diagnosing TCV with cytologic preparations. Cancer (Cancer Cytopathol)


Asunto(s)
Carcinoma Papilar/genética , Pérdida de Heterocigocidad/genética , Recurrencia Local de Neoplasia/genética , Neoplasias de la Tiroides/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Papilar/secundario , Cromosomas Humanos Par 1/genética , Análisis Mutacional de ADN , ADN de Neoplasias/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Reacción en Cadena de la Polimerasa , Neoplasias de la Tiroides/patología , Proteína p53 Supresora de Tumor/análisis
19.
20.
J Clin Endocrinol Metab ; 84(6): 2086-92, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10372715

RESUMEN

The expression of integrin laminin receptors was investigated in normal thyroid primary cultures; immortalized normal thyroid cells (TAD-2); papillary (NPA), follicular (WRO), and anaplastic (ARO) thyroid tumor cell lines; seven thyroid tumors (four papillary and three follicular carcinomas); and normal thyroid glands. The expression of alpha1beta1, alpha2beta1, alpha3beta1, alpha6beta1, and alpha6beta4 was found in all tumor specimens and in tumor cell lines, whereas normal thyroid cells and TAD-2 cells lacked the expression of alpha6beta4. Despite the presence of several integrin laminin receptors, adhesion of TAD-2, NPA, and ARO cells to immobilized laminin-1 was poor, whereas WRO cells and follicular carcinoma-derived cells displayed a strong adhesion. Indeed, WRO and follicular carcinoma-derived cells showed expression of a nonintegrin laminin receptor, the 67-kDa high affinity laminin receptor (67LR). TAD-2, NPA, and ARO cells as well as nodular goiter, toxic adenoma, follicular adenoma, and papillary carcinoma-derived cells did not express the 67LR. Adhesion of WRO and follicular carcinoma-derived cells to laminin-1 was specifically inhibited by a recombinant polypeptide containing laminin-binding domains of 67LR, demonstrating that this receptor confers to follicular carcinoma cells attachment capacity to laminin. Moreover, tissue specimens from follicular carcinomas expressed the 67LR, whereas follicular adenomas and normal thyroid tissues were negative. In thyroid tumors, integrin receptors, although abundant, participate weakly in adhesion to laminin. The expression in follicular carcinoma cells of a functional, high affinity 67LR together with nonfunctional integrin LM receptors could be responsible for the tendency of follicular carcinoma cells to metastasize by mediating stable contacts with basal membranes.


Asunto(s)
Adenocarcinoma Folicular/metabolismo , Precursores de Proteínas , Receptores de Laminina/biosíntesis , Neoplasias de la Tiroides/metabolismo , Biotina/metabolismo , Western Blotting , Adhesión Celular , Citometría de Flujo , Humanos , Laminina/fisiología , Pruebas de Precipitina , Glándula Tiroides/metabolismo , Glándula Tiroides/patología , Células Tumorales Cultivadas
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