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1.
Nano Lett ; 14(11): 6572-7, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25329836

RESUMEN

A novel lithium-oxygen battery exploiting PYR14TFSI-LiTFSI as ionic liquid-based electrolyte medium is reported. The Li/PYR14TFSI-LiTFSI/O2 battery was fully characterized by electrochemical impedance spectroscopy, capacity-limited cycling, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The results of this extensive study demonstrate that this new Li/O2 cell is characterized by a stable electrode-electrolyte interface and a highly reversible charge-discharge cycling behavior. Most remarkably, the charge process (oxygen oxidation reaction) is characterized by a very low overvoltage, enhancing the energy efficiency to 82%, thus, addressing one of the most critical issues preventing the practical application of lithium-oxygen batteries.

2.
Ann Chir Plast Esthet ; 58(3): 243-7, 2013 Jun.
Artículo en Francés | MEDLINE | ID: mdl-20880625

RESUMEN

The authors reexamined the files of seven patients dealt with for intramuscular hemangioma of forearm. It concerns five women and two men, between 16 and 39 years old. The average time of consultation was 13 months. The clinical signs were dominated by the development of a generally painless soft mass over the anterior compartment of the forearm and/or the elbow. Two patients presented nervous lesions signs of the ulnar or median nerves. The feeder pedicle was the ulnar artery in five cases and radial artery in two cases. The excision was incomplete in two cases because of the invasion of the ulnar nerve by the hemangioma. With four years average follow-up, the five patients having undergone a complete excision do not present a recurrence and the hand function is excellent. The authors insist on the interest of a preoperative diagnosis with the IRM, which permits to envisage surgical difficulties due to the proximity of vascular and nervous pedicles.


Asunto(s)
Antebrazo/cirugía , Hemangioma/cirugía , Neoplasias de los Músculos/cirugía , Adolescente , Adulto , Femenino , Hemangioma/patología , Humanos , Masculino , Neoplasias de los Músculos/patología , Estudios Retrospectivos , Adulto Joven
3.
Ann Chir Plast Esthet ; 56(2): 160-2, 2011 Apr.
Artículo en Francés | MEDLINE | ID: mdl-20573436

RESUMEN

Hibernoma is a rare benign tumour of brown fat. It presents as a voluminous slow-growing mass in the regions where remnants of brown fat can remain in adults. We report a case of a hibernoma on the thigh and present the diagnostic and therapeutic elements of this type of tumour, whose differential diagnosis of liposarcoma.


Asunto(s)
Lipoma/cirugía , Muslo/cirugía , Adipocitos/patología , Anciano , Biopsia , División Celular , Diagnóstico Diferencial , Humanos , Lipoma/diagnóstico , Lipoma/patología , Masculino , Muslo/patología , Tomografía Computarizada por Rayos X
4.
Chir Main ; 27(6): 266-8, 2008 Dec.
Artículo en Francés | MEDLINE | ID: mdl-18996040

RESUMEN

Elastofibroma dorsi is a slowly-growing benign tumor which usually occurs at the inferior angle of the scapula. It may be more of a degenerative process than a neoplasia. We seek, through our observations and a review of the literature, to clarify the characteristics of this tumor and its modes of management. We think that all doctors should be aware of this condition, in order to treat it correctly.


Asunto(s)
Fibroma/patología , Neoplasias de los Tejidos Blandos/patología , Femenino , Fibroma/cirugía , Humanos , Persona de Mediana Edad , Hombro , Neoplasias de los Tejidos Blandos/cirugía
5.
Oncogene ; 2(2): 149-56, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2835724

RESUMEN

Inbred athymic nu/nu mice (BALB/c and C57BL/6) were injected subcutaneously with polyoma virus A2 strain or with polyoma mutants which are able to infect undifferentiated embryonal carcinoma cells and harbor mutations in their enhancer sequences. Mammary adenocarcinomas were induced exclusively in females in which they represent the majority of the tumors. Both males and females developed sarcomas, mostly osteosarcomas, with a similar low frequency. No other type of neoplasm was observed. Mutations affecting the enhancers do not have any effect on the histotype of the tumors. Multiple copies of intact or defective free viral DNA were detected in all tumors. Such a sex-linked specific tissue targeting suggests a hormonal control of tumor initiation and/or promotion. From a pathological point of view, polyoma-induced adenocarcinomas are very similar to human early breast cancers. Tumor induction in nude mice by polyoma virus therefore represents a unique experimental model which differs from the more extensively used newborn immunocompetent mice.


Asunto(s)
Neoplasias Mamarias Experimentales/etiología , Osteosarcoma/etiología , Poliomavirus/patogenicidad , Sarcoma Experimental/etiología , Animales , Antígenos Transformadores de Poliomavirus/genética , ADN Viral/genética , Neoplasias Mamarias Experimentales/genética , Ratones , Ratones Desnudos , Osteosarcoma/genética , Sarcoma Experimental/genética , Factores Sexuales
6.
Leukemia ; 11(11): 1868-77, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9369420

RESUMEN

Fas ligand (FasL) is capable of inducing apoptosis of lymphoid cells by cross-linking with its natural receptor, Fas. We aimed to investigate the possible role of the Fas/FasL-mediated apoptosis in the development of human lymphomas. FasL mRNA was detected by reverse transcriptase-polymerase chain reaction in 38 out of 63 lymphoma biopsy specimens representative of various subtypes of non-Hodgkin's lymphoma (NHL) and Hodgkin's disease. FasL was co-expressed with Fas mRNA in most cases. Flow cytometry (FACS) analysis showed a bright FasL staining in 31% to up to 75% of the total cell population from 14 out of 16 samples; the presence of the FasL protein was confirmed by Western blotting. Dual-color FACS analysis showed that FasL was expressed by T cells in B-NHLs and T-NHLs. A significant percentage of B cells in various B-NHLs also stained positively for FasL. Freshly separated neoplastic B cells from three FasL+ and one FasL- B-NHLs displayed a relative resistance to Fas-mediated apoptosis, when compared to reactive T cells isolated from the same tissue samples. In contrast, the sensitivity to Fas-mediated killing of the T cells isolated from two FasL+ T-NHLs was not uniform. These data show that (1) FasL is expressed in both neoplastic and reactive cells from a significant proportion of lymphoma cases, and (2) that the intratumoral FasL+/Fas+ reactive T cells are more sensitive to Fas-induced apoptosis than the neoplastic FasL+/Fas+ malignant B cells. A putative defect in the Fas/FasL pathway may thus favor the development of malignant B cell populations.


Asunto(s)
Apoptosis , Linfoma/metabolismo , Glicoproteínas de Membrana/metabolismo , ARN Mensajero/metabolismo , Receptor fas/metabolismo , Western Blotting , Técnicas de Cultivo de Célula , Proteína Ligando Fas , Citometría de Flujo/métodos , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/metabolismo , Humanos , Linfoma/genética , Glicoproteínas de Membrana/genética , Reacción en Cadena de la Polimerasa , Células Tumorales Cultivadas , Receptor fas/genética
7.
Leukemia ; 13(10): 1548-53, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10516756

RESUMEN

To determine whether the expression levels of Bcl-2 family apoptotic regulators are correlated with the histopathological heterogeneity of B cell non-Hodgkin's lymphomas (NHL), we quantified their expression in malignant B cell populations isolated from 33 biopsy samples, including small lymphocytic lymphoma (SLL, n = 9), mantle cell lymphoma (MCL, n = 8), follicular lymphoma (FL, n = 8), and diffuse large cell lymphoma (DLCL, n = 8). Normal B cells purified from reactive lymph nodes and tonsil (n = 3) were used as controls. Cell lysates were analyzed by Western blotting, and signals quantified by densitometry. Expression of Bcl-2 and its homologues, Bcl-xL, Bcl-xS, Bax, Bad, Bak and Bag-1, was detected in all NHL cases, with wide variations between histological subtypes and within each subtype. Statistically significant differences were: (1) a higher level of Bad expression in DLCL compared to FL and MCL; (2) a lower level of Bak expression in FL compared to DLCL, SLL and MCL; and (3) a higher Bag-1 expression level in FL compared to SLL. When compared to NHL cells, normal B cells showed a higher level of Bax expression, and a lower level of Bcl-xL expression. Thus, quantitative analysis shows ubiquitous expression of Bcl-2 family proteins in normal and neoplastic B cells; the variations in expression levels may contribute to both the B-NHL clinicopathological diversity and the different apoptotic sensitivities of normal B cells vs B-NHL cells.


Asunto(s)
Apoptosis/fisiología , Linfoma no Hodgkin/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Biopsia , Proteínas Portadoras/biosíntesis , Proteínas de Unión al ADN , Humanos , Linfoma no Hodgkin/patología , Proteínas Proto-Oncogénicas/biosíntesis , Factores de Transcripción , Proteína X Asociada a bcl-2 , Proteína Letal Asociada a bcl
8.
Brain Pathol ; 3(3): 297-306, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8293189

RESUMEN

The central neurocytoma is a supratentorial, often calcified brain tumour affecting young adults and is typically located in the lateral ventricles in the region of the foramen of Monro. Clinically, the tumour causes signs of increased intracranial pressure, visual and mental disturbances and, occasionally, pyramidal or endocrine symptoms. By light microscopy, the tumour is composed of small round cells in a delicate fibrillary matrix. Tumour cells consistently show features of neuronal differentiation by electron microscopy (synapses, dense-core vesicles, presynaptic clear vesicles, specialized synaptic junctions) and immunoreactivity for synaptophysin and other neuronal marker proteins. The tumour can be totally removed in nearly half of the cases. After incomplete surgical resection neurocytomas may recur but because of their low proliferation potential, radio- or chemotherapy are not generally recommended. Postoperative recurrence-free survival times of up to 19 years have been reported. Neurocytomas constitute nearly one half of supratentorial intraventricular tumours in adults but amount to less than 1% of all tumours of the central nervous system and its coverings.


Asunto(s)
Neoplasias Encefálicas/patología , Neurocitoma/patología , Neoplasias Encefálicas/fisiopatología , Femenino , Humanos , Masculino , Neurocitoma/fisiopatología
9.
J Clin Endocrinol Metab ; 59(5): 817-24, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6480809

RESUMEN

A 43-yr-old woman, who had previously had a subtotal thyroidectomy, presented with hyperthyroidism and amenorrhea-galactorrhea due to a pituitary adenoma secreting TSH, TSH-alpha, and PRL. Her serum T4 concentration was 14 micrograms/dl; T3, 5.7 ng/ml, and TSH, 19-33 microU/ml. Serum TSH was not altered by TRH stimulation or T3 suppression. Basal plasma PRL levels were 19-27 ng/ml and plasma PRL doubled after TRH stimulation. A 900-mg pituitary tumor, removed by transphenoidal surgery, was studied in cell culture. After dispersion, tumor cells were maintained on an extracellular matrix produced by bovine corneal endothelial cells in a defined serum-free medium. The hormones released in the culture medium were analyzed by high pressure gel chromatography. Three fractions of tumor TSH were found, with respective apparent mol wts of 45,000 (11%), 28,000 (70%), and 20,000 (19%). Tumoral PRL eluted as a single peak of apparent mol wt of 24,000. Pharmacological studies of TSH, TSH-alpha, and PRL release using thyroid hormones (T3), dopamine agonist (bromocriptine), TRH, and cholera toxin yielded the following results: 1) T3 after 3 days of incubation produced a dose-dependent inhibition of TSH, TSH-alpha, and PRL release. Maximal inhibition (81%) was obtained at 10(-9) M and half-maximal inhibition at 4-6 X 10(-11) M. 2) Bromocriptine produced rapid and partial inhibition of hormone release. Maximal inhibition (51%) was obtained at 10(-8) M and half-maximal inhibition at 5 X 10(-10) M. 3) TRH at 10(-8) M concentration significantly stimulated PRL release but it had no effect on TSH release. 4) Adenylate cyclase activation by 10(-11) M cholera toxin increased TSH (152%), TSH-alpha (150%), and PRL (220%). Immunohistochemical analysis of serial 2 micron sections of the tumor showed that: 1) TSH-alpha immunoreactive cells were the most numerous, 2) TSH-beta positive cells were always positive for TSH-alpha, 3) PRL immunoreactivity was found either uniquely in some cells and colocalized with TSH-alpha immunoreactivity in other cells. However, by electron microscopy, the tumor cells were thyrotrophs. These data indicate that in this patient's tumor: 1) cells secreting TSH were responsive in vitro to near physiological concentrations of thyroid hormones. 2) The colocalization of PRL and TSH-alpha immunoreactivities in some cells raises the possibility either of fusion of differentiated pituitary cells synthesizing distinct hormones or of transformation of less differentiated multipotential pituitary cells.


Asunto(s)
Adenoma/metabolismo , Neoplasias Hipofisarias/metabolismo , Prolactina/metabolismo , Tirotropina/metabolismo , Adenoma/sangre , Adenoma/ultraestructura , Adulto , Bromocriptina/farmacología , Células Cultivadas , Femenino , Histocitoquímica , Humanos , Hipertiroidismo/sangre , Hipertiroidismo/etiología , Inmunoquímica , Neoplasias Hipofisarias/sangre , Neoplasias Hipofisarias/ultraestructura , Radioinmunoensayo , Tirotropina/sangre , Triyodotironina/farmacología
10.
J Clin Endocrinol Metab ; 61(4): 686-92, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4031013

RESUMEN

In an effort to better characterize the ultrastructural, morphometric, and immunocytochemical changes induced by 10(-8) M bromocriptine (BR), tumor cells from three surgically removed PRL-producing pituitary adenomas were cultured on an extracellular matrix in serum-free medium. In each instance, the treated cultures were compared to control cells at the end of 24 h and 16 days. PRL RIAs were performed on culture medium. A decrease in cell and nucleus surface area was found on day 16 in two cultures. This supports the well known shrinkage of BR-treated PRL-producing adenomas. BR induced no change in these parameters in the tumor from a third patient who was partly resistant to the drug. Changes in the secretory process were discernible as of day 1 in all three tumors, with a dramatic reduction of exocytosis and intracellular accumulation of PRL-immunoreactive granules. This induced delayed inhibition of protein synthesis, demonstrated by preembedding immunocytochemistry on day 16. These results, obtained for the first time in human PRL-producing adenomas, are informative as to the subcellular events subsequent to short term BR treatment and illustrate that secretory inhibition and tumor shrinkage are not necessarily linked.


Asunto(s)
Adenoma/ultraestructura , Bromocriptina/farmacología , Neoplasias Hipofisarias/ultraestructura , Adenoma/análisis , Adolescente , Adulto , Células Cultivadas , Femenino , Histocitoquímica , Humanos , Inmunoquímica , Masculino , Microscopía Electrónica , Neoplasias Hipofisarias/análisis
11.
J Immunol Methods ; 98(2): 173-81, 1987 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-3571984

RESUMEN

Monoclonal antibodies were prepared against human thyrotropin. 13 different antibodies were characterized. Ten antibodies were of the IgG1 subclass. The affinities of the antibodies were in the range 10(9)-10(11) mol-1 X l. Four of them were specific for hTSH and did not react with hLH, hFSH, hCG or alpha hCG. Four reacted with these hormones and recognized the alpha subunit of hCG. One cross-reacted only with hFSH. The remaining four antibodies recognized the holo-hTSH only, and thus were designated as anti-conformational determinants. Monoclonal antibodies reacting with different antigenic determinants on the hTSH molecule defined seven clusters. Two of them were used to develop a simplified two-site sandwich radioimmunoassay in which one monoclonal antibody was immobilized on tubes (anti-beta TSH) and another (anti-alpha) labelled with 125I. This assay was highly specific and demonstrated a sensitivity level of 0.1 microIU/ml. Two monoclonal antibodies were used in immunohistochemistry and their quality and specificity was assessed in the detection of hTSH immunoreactivity in human pituitary biological sections.


Asunto(s)
Anticuerpos Monoclonales , Radioinmunoensayo/métodos , Tirotropina/sangre , Anticuerpos Monoclonales/aislamiento & purificación , Especificidad de Anticuerpos , Gonadotropina Coriónica/sangre , Reacciones Cruzadas , Histocitoquímica , Humanos , Hipertiroidismo/sangre , Hipotiroidismo/sangre , Radioisótopos de Yodo , Conformación Proteica
12.
Am J Surg Pathol ; 16(2): 97-109, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1370756

RESUMEN

We report herein the clinical and pathological features of 20 patients with central neurocytomas. Investigations for various differentiation antigens and cell type-specific markers were performed by immunohistochemistry using paraffin-embedded tissue. In addition, the expression of L1 adhesion molecule and of the various N.CAM (neural cell adhesion molecule) isoforms were investigated by immunoblotting studies in two frozen specimens. Central neurocytomas are clinically characterized by their intraventricular localization, occurrence in young adults, and good prognosis. It rarely occurs in patients over 50, but such cases have a poor prognosis. Total surgical excision is the best treatment. Radiotherapy is appropriate if surgery is incomplete or contraindicated. Histologically, central neurocytomas display the following features: an oligo-like pattern, usually associated with large fibrillary rosettes or perivascular arrangement, and a rich endocrine-type vasculature. Central neurocytomas have a remarkably homogeneous antigenic profile. GFAP expression is only found in scattered reactive astrocytes, S100 protein in reactive astrocytes and rare tumor cells. Among the pan-neuroendocrine markers, central neurocytomas always express neuron-specific enolase; they frequently express synaptophysin but never chromogranin A. Synaptophysin is the most reliable immunohistological marker for central neurocytomas; however, immunoreactivity could be lost with long formalin fixation. In these cases, electron microscopy is used to support the neuronal nature of the tumor cells. The expression of L1 adhesion molecule and the isoform 180 of N.CAM, indicates that central neurocytomas are formed by cells committed to neuronal phenotype. Nevertheless, advanced neuronal differentiation may be absent, as suggested by the persistence of embryonic N.CAM, the nonexpression of neurofilament proteins, and the absence of mature synapses in numerous cases. Central neurocytomas and neuroblastomas share some biochemical properties, but their respective clinicopathological features and biological behavior are dramatically different.


Asunto(s)
Neoplasias del Ventrículo Cerebral/patología , Neuroblastoma/patología , Adolescente , Adulto , Biomarcadores de Tumor/análisis , Moléculas de Adhesión Celular Neuronal/análisis , Neoplasias del Ventrículo Cerebral/química , Neoplasias del Ventrículo Cerebral/ultraestructura , Epítopos , Femenino , Proteína Ácida Fibrilar de la Glía/análisis , Humanos , Immunoblotting , Inmunohistoquímica , Complejo de Antígeno L1 de Leucocito , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Neuroblastoma/química , Neuroblastoma/ultraestructura , Fenotipo , Proteínas S100/análisis , Sinaptofisina/análisis
13.
J Neuroimmunol ; 11(4): 301-10, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3011857

RESUMEN

The existence of an immunological blood-brain barrier (BBB) is well established but its role in cerebral tumour immunology is less well defined. Attempting to clarify this problem we tested the graft rejection of polyoma virus-induced central nervous (CNS) tumours in hamsters after systemic or intracerebral immunization with polyoma virus. Animals were immunized by intracerebral or subcutaneous inoculations of polyoma virus before tumours were induced by intracerebral or intramuscular graft of polyoma-transformed hamster neuroglial cells. The growth of cerebral and muscular tumours was significantly inhibited in animals immunized subcutaneously. In animals immunized intracerebrally the inhibition of growth was highly significant for cerebral tumours and only very slight for intramuscular tumours. These results suggest that the blood-brain barrier allowed immunocompetent effector cells to penetrate inside the CNS but prevented the locally elicited cell-mediated immune response from diffusing outside the CNS. The ability of the brain to develop a local immune response and the partial lack of circulation of immunocompetent cells to cross the BBB could be mainly responsible for the special immune status of the CNS and may greatly interfere with the establishment of an efficient immune response toward brain tumours.


Asunto(s)
Barrera Hematoencefálica , Neoplasias Encefálicas/inmunología , Infecciones Tumorales por Virus/inmunología , Animales , Anticuerpos Antivirales/inmunología , Neoplasias Encefálicas/etiología , Cricetinae , Mesocricetus , Trasplante de Neoplasias , Poliomavirus/inmunología , Infecciones Tumorales por Virus/complicaciones
14.
Int J Oncol ; 23(1): 97-103, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12792781

RESUMEN

Undifferentiated carcinoma of the nasopharyngeal type (UCNT) that histologically mimics Hodgkin's lymphoma (HL) ("Hodgkin's lymphoma-like UCNT"--HL-like UCNT) is known as a diagnostic pitfall. Using immunohistochemistry, Western blot and cDNA array technology, we wanted to document its phenotypical and molecular characteristics. We report herein 5 cases of UCNT that morphologically mimic HL and 3 classical UCNT cases. We compared the expression profiles of a thousand selected genes in HL-like UCNT and in classical UCNT cases. No difference in the profile of EBV infection was noted between the HL-like UCNT and control cases. Significant differences were detected in the expression of genes involved in the matrix modelling, angiogenesis, apoptosis and regulation of the Th-2 interleukins. The eosinophil chemoattractant eotaxin was expressed in the stroma of HL-like UCNT, but not in the control cases. The eotaxin receptor CCR3 was expressed in both stromal and carcinoma cell populations of HL-like UCNT, this pattern being similar to the one observed in HL. These results show that UCNT morphologically resembling HL share also some specific phenotypical and molecular features with HL, and might deserve to be isolated as a particular UCNT subtype.


Asunto(s)
Carcinoma/patología , Enfermedad de Hodgkin/patología , Linfoma/patología , Neoplasias Nasofaríngeas/patología , Apoptosis , Western Blotting , Carcinoma/clasificación , ADN Complementario/metabolismo , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/clasificación , Humanos , Inmunohistoquímica , Inmunofenotipificación , Hibridación in Situ , Intrones , Linfoma/clasificación , Neoplasias Nasofaríngeas/clasificación , Neovascularización Patológica , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo
15.
Hum Pathol ; 11(2): 207-10, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7399509

RESUMEN

This report presents the ultrastructural study of a germinoma of the third ventricle occurring in a 13 year old boy. The electron microscopic data showed similarities linking this tumor to gonadal and mediastinal germinomas and emphasized the exceptional glycogenic storage in tumor and stroma cells. Another morphological analogy was the intense macrophagic activity that led to tumor cell phagocytosis. The authors discuss the meaning of such an immune response, which is usually not observed in cerebral tumors.


Asunto(s)
Neoplasias Encefálicas/patología , Disgerminoma/patología , Macrófagos/fisiología , Adolescente , Neoplasias Encefálicas/ultraestructura , Disgerminoma/ultraestructura , Humanos , Macrófagos/ultraestructura , Masculino
16.
Hum Pathol ; 25(5): 449-54, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8200638

RESUMEN

Expression of the p53 protein has been detected recently by immunohistochemistry in Hodgkin's disease (HD), but the relationship between p53 expression and the prognosis and clinicopathological heterogeneity of HD is still unclear. To address these questions we investigated 49 cases of HD for p53 expression by immunohistochemistry using the DO1 monoclonal antibody (MAb) on paraffin sections. Thirty-five cases were simultaneously tested with the 1801 MAb on frozen sections. Thirty-seven of 49 cases (75%) were DO1 positive while 14 of 35 (40%) were PAb 1801 positive. Both MAbs gave a nuclear staining restricted to Reed Sternberg cells (RSCs) and variants and distributed among the three HD subtypes analyzed (ie, nodular lymphocyte predominant, nodular sclerosing, and mixed cellularity). The percentage of positive neoplastic cells in each case was heterogeneous, ranging from almost 100% to less than 5%. In 39 patients for whom clinical data were available statistical analysis did not show any significant correlation between p53-positive immunostaining and clinical staging, B symptoms, probability of relapse, or disease-free survival. We conclude that p53 expression is a common event in HD regardless of histological subtyping, but does not bear any pejorative significance.


Asunto(s)
Enfermedad de Hodgkin/genética , Proteína p53 Supresora de Tumor/biosíntesis , Anticuerpos Monoclonales , Estudios de Seguimiento , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Humanos , Técnicas para Inmunoenzimas , Pronóstico , Células de Reed-Sternberg/metabolismo , Análisis de Supervivencia , Proteína p53 Supresora de Tumor/genética
17.
Hum Pathol ; 21(9): 911-7, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2168337

RESUMEN

Several findings suggest an etiologic relationship between genital tract squamous cell carcinoma and certain types of human papillomavirus (HPV). Detection of these HPV types in cervical lesions considered as preneoplastic states (ie, cervical intraepithelial neoplasia or CIN) is extremely important but difficult because the morphology of these states is highly heterogeneous and clinical course is rarely predictable. In situ hybridization (ISH) is the only technique allowing correlation between HPV type and tissue or cell morphology. In this report, 110 biopsy specimens from uterine cervix lesions were studied: 66 CIN, 10 invasive carcinoma, 28 metaplasia, and six condyloma acuminata. A new ISH technique based on direct modification of DNA probes by sulfonation was used. The hybridized DNA was revealed first by a specific monoclonal antibody against sulfonated DNA, and then by an alkaline phosphatase system. In order to determine the sensitivity level of this method, 14 biopsy specimens were also submitted to Southern blot hybridization. Five probes were used separately (HPV 6, 11, 16, 18, and 33) for each biopsy specimen. Results of ISH were correlated with morphologic criteria such as number of koilocytes and mitoses. Oncogenic HPV was found exclusively in CIN. The number of labeled cells varied with CIN grade. These data suggest that, whatever the grade, CIN represents a unique preneoplastic process, and that HPV replication depends on the squamous maturation of the pathologic epithelium.


Asunto(s)
Carcinoma de Células Escamosas/microbiología , Sondas de ADN de HPV , Sondas de ADN , Hibridación de Ácido Nucleico , Papillomaviridae/clasificación , Neoplasias del Cuello Uterino/microbiología , Southern Blotting , Carcinoma de Células Escamosas/patología , Colorimetría , Femenino , Humanos , Papillomaviridae/genética , Neoplasias del Cuello Uterino/patología
18.
Hum Pathol ; 28(8): 912-21, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9269827

RESUMEN

Ich-1/Nedd2 and CPP32/YAMA are cysteine proteases related to interleukin 1-beta-converting enzyme (ICE), which act as apoptosis effectors. Both molecules are expressed in T- and B-cell lines. The authors investigated their in vivo cellular distribution in normal and neoplastic human lymphoid tissues. Sixty-eight representative non-Hodgkin's lymphomas (NHL) and Hodgkin's disease (HD) samples, normal lymphoid organs, and nonlymphoid tumors were analyzed by immunohistochemistry (IHC). CPP32 expression in benign tissues was restricted to germinal center B cells, plasma cells, and a few interfollicular immunoblasts. All follicular NHLs and most diffuse large cell NHLs were CPP32 positive. Among T-cell NHLs, CPP32 expression was mainly observed in anaplastic large cell NHLs, whereas the other subtypes were less frequently positive. In contrast, lymphoid organs displayed only weak Ich1-L expression, located in sinusal histiocytes and thymic epithelial cells. Lymphomas were Ich1-L negative, except for T-cell-rich B-cell NHLs, and about half of the HD samples, in which Reed-Sternberg cells (RSC) were usually Ich1-L positive/CPP32 negative. Extralymphoid Ich1-L reactivity was found in particular organs like the kidney and various tumors. Western blot analysis confirmed the specificity of immunostaining. Neither CPP32 nor Ich1-L expression were correlated with intratumoral DNA fragmentation, as determined by the TUNEL assay. Altogether, these results indicate that CPP32 is preferentially expressed in germinal centers and thus could be involved in B-cell maturation. The differential expression of CPP32 and Ich1-L suggests that cysteine proteases differ in substrate specificities and carry out functions unrelated to apoptosis.


Asunto(s)
Linfocitos B/metabolismo , Caspasas , Cisteína Endopeptidasas/metabolismo , Enfermedad de Hodgkin/metabolismo , Linfoma no Hodgkin/metabolismo , Proteínas/metabolismo , Apoptosis , Biopsia , Western Blotting , Caspasa 2 , Caspasa 3 , Fragmentación del ADN , Humanos , Inmunohistoquímica , Ganglios Linfáticos/metabolismo , Tonsila Palatina/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Bazo/metabolismo , Timo/metabolismo
19.
APMIS ; 100(10): 949-53, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1445701

RESUMEN

The hormone gastrin is mainly produced by the G cells of the antral mucosa and plays a major role in the regulation of digestive mucosal growth. Since it permits identification of cell types containing mRNA, in situ hybridization (ISH) appears to be an interesting method for studying gastrin-producing tissues. In this study, in situ detection of gastrin mRNA has been carried out on frozen sections of four human normal antral mucosa samples and of six colonic carcinomas removed from patients with high levels of plasma gastrin, using a gastrin oligonucleotidic DNA probe. We have compared the results provided respectively by the [35s] labelling and the digoxigenin labelling of the synthetic probe. Positive cells were found in each normal sample analysed with radioactive- as well as digoxigenin-labelled antisense probes. The total number of cells expressing gastrin mRNA appeared slightly higher with the [35s]-labelled probe, while the digoxigenin-labelled probe gave a better definition of positive signals. In contrast, neither radioactive nor cold probes gave positive signals in the six colonic carcinoma samples, although gastrin expression had been demonstrated in these tumours using a reverse transcriptase-PCR method. These results show that, although ISH does not seem sensitive enough to allow the detection of very low levels of gastrin expression, it would appear to be a reliable method for visualizing gastrin mRNA in human antral mucosa.


Asunto(s)
Gastrinas/genética , Hibridación in Situ , ARN Mensajero/análisis , Secuencia de Bases , Neoplasias del Colon/química , Sondas de ADN , Digoxigenina , Mucosa Gástrica/química , Humanos , Datos de Secuencia Molecular , Radioisótopos de Azufre
20.
APMIS ; 102(7): 526-32, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7917222

RESUMEN

Gastrin, a peptide hormone produced by the G cells of the gastric antrum, plays a major role in the regulation of digestive mucosal growth. Although some light has been shed on the peptidic aspects of this hormone's mode of action and the co-regulatory activity in which it is involved along with the other gastrointestinal hormones, little is known at present about the modes of expression of its mRNA at the tissue level. A few attempts have been made so far to detect the transcript, mostly using molecular hybridization techniques. Here it was proposed to detect gastrin mRNA using a RT-PCR technique on a series of paraffin-embedded samples of normal human antrum processed with various fixatives commonly used in histology. The transcript was detectable in all the 7-microns sections of the samples treated with either formalin or Carnoy's solution, whereas Bouin's solution, which is also used as a fixative in histology, was found to have inhibitory effects on the method described here.


Asunto(s)
Ácido Acético , Fijadores , Mucosa Gástrica/química , Gastrinas/genética , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , Acetatos , Secuencia de Bases , Southern Blotting , Cloroformo , Etanol , Formaldehído , Humanos , Datos de Secuencia Molecular , Adhesión en Parafina , Picratos , Antro Pilórico/química , ARN Mensajero/genética
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