Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Database
Publication year range
1.
Nature ; 598(7880): 272-275, 2021 10.
Article in English | MEDLINE | ID: mdl-34646001

ABSTRACT

Studies1,2 have shown that the remnants of destroyed planets and debris-disk planetesimals can survive the volatile evolution of their host stars into white dwarfs3,4, but few intact planetary bodies around white dwarfs have been detected5-8. Simulations predict9-11 that planets in Jupiter-like orbits around stars of ≲8 M☉ (solar mass) avoid being destroyed by the strong tidal forces of their stellar host, but as yet, there has been no observational confirmation of such a survivor. Here we report the non-detection of a main-sequence lens star in the microlensing event MOA-2010-BLG-477Lb12 using near-infrared observations from the Keck Observatory. We determine that this system contains a 0.53 ± 0.11 M☉ white-dwarf host orbited by a 1.4 ± 0.3 Jupiter-mass planet with a separation on the plane of the sky of 2.8 ± 0.5 astronomical units, which implies a semi-major axis larger than this. This system is evidence that planets around white dwarfs can survive the giant and asymptotic giant phases of their host's evolution, and supports the prediction that more than half of white dwarfs have Jovian planetary companions13. Located at approximately 2.0 kiloparsecs towards the centre of our Galaxy, it is likely to represent an analogue to the end stages of the Sun and Jupiter in our own Solar System.

2.
Ann Pathol ; 11(4): 271-4, 1991.
Article in French | MEDLINE | ID: mdl-1958261

ABSTRACT

A 48 year old woman presented peripheral eosinophilia and neurologic symptoms which were related to a right parietal hypodense lesion. Further investigation led to the discovery of a left atrial cardiac tumor which had been incompletely resected and diagnosed as sarcoma. Eosinophilia than decreased. Two months after cardiac surgery, intracranial hypertension appeared and another expansive cerebral mass was discovered on CT scan. The patient was treated by radiotherapy. Two years later, the patient presented left abdominal pain. An increase of eosinophilic rate was noted. Abdominal CT scan revealed an heterogenous mass in the spleen. Splenectomy was performed and the tumor was diagnosed as a metastasis of the cardiac sarcoma. This case illustrates a rare tumor which is distinctive by its clinical signs: peripheral eosinophilia and neurologic signs. There were no cardiac symptoms. The clinical evolution was good after more than two years from initial diagnosis. This implies that a surgical attitude is recommended in such cases.


Subject(s)
Eosinophilia/pathology , Heart Neoplasms/pathology , Paraneoplastic Syndromes/pathology , Sarcoma/pathology , Female , Heart Neoplasms/blood , Humans , Immunoenzyme Techniques , Middle Aged , Sarcoma/blood
3.
Am J Surg Pathol ; 14(11): 1024-35, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2240355

ABSTRACT

Five cases of nodular, lymphocyte predominant Hodgkin's disease (nLP HD), in which an association with (n = 3) and transformation to (n = 2) large cell lymphoma (LCL) were found, were studied with monoclonal antibodies against B-, T-, and Reed-Sternberg (R-S) cell-associated antigens and epithelial membrane antigen (EMA) on paraffin sections. Both lymphocytic (L) and histiocytic (H) cells of nLP HD and lymphoma cells of LCL expressed multiple B-cell-associated antigens (detected by LN-1/CDw75, L26, MB2, DBB.42, DBA.44, DND.53, DNA.7 antibodies) but did not react with antibodies against T-cell-associated (MT1, UCHL1/CD45RO) (one exception for CD45RO in LCL) and R-S cell-associated (Leu-M1/CD15, Ber-H2/CD30) antigens. EMA was expressed by L and H cells in all cases and conserved in LCL cells, emphasizing the frequent expression of EMA by the diagnostic cells of nLP HD. An antibody (BNH9) against blood group-related antigens (H and Y oligosaccharide antigens) that does not normally react with lymphoid cells was found to be reactive with few L and H cells in two of five and most LCL cells in four of five cases. The finding might be indicative of abnormal activation of lymphoid cells. The data reinforce current implications that nLP HD is a B-cell malignancy in evolution and that it is not truly representative of Hodgkin's disease in terms of biological and clinical behavior.


Subject(s)
Hodgkin Disease/pathology , Lymphoma, Large B-Cell, Diffuse/pathology , Adult , Antibodies, Monoclonal , B-Lymphocytes/immunology , Cell Transformation, Neoplastic/pathology , Female , Humans , Male , Middle Aged , T-Lymphocytes/immunology
4.
Br J Cancer ; 62(2): 177-82, 1990 Aug.
Article in English | MEDLINE | ID: mdl-1974813

ABSTRACT

The distribution of Gp 170, a multidrug resistance (MDR) associated glycoprotein, also called P-glycoprotein (P-gp), was examined by immunohistochemistry, using C219 and MRK16 monoclonal antibodies. Sixty-five tumour tissues were studied which included 40 non-lymphoid tumours, 15 chemoresistant non-Hodgkin's lymphomas and 10 Hodgkin's disease. The study was performed on both cryostat and special fixation processed and paraplast embedded (ModAMeX) sections. The latter method preserves fixation-sensitive antigens such as P-gp and allows a more precise morphological identification of neoplastic and non-neoplastic cell populations in contrast to cryostat sections. Immunohistochemical expression of P-gp was expected and confirmed in many non-lymphoid tumours, but stromal macrophages and endothelial cells were also frequently stained in these cases. In non-Hodgkin's lymphomas, cells that were stained with both C219 and MRK16 monoclonal antibodies on cryostat sections were identified as macrophages and endothelial cells and not neoplastic lymphoid cells, by the ModAMeX technique. These findings suggest that the quantitative assessment of MDR RNA by Northern blotting performed on fresh homogenates overestimates the MDR content of neoplastic cells in a number of lymphoid and non-lymphoid tumours. In addition, the mechanism of chemoresistance in non-Hodgkin's lymphomas is less likely to be associated with P-gp expression.


Subject(s)
Extracellular Matrix/metabolism , Membrane Glycoproteins/metabolism , Neoplasms/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Animals , Antibodies, Monoclonal/immunology , Cricetinae , Cricetulus , Drug Resistance , Extracellular Matrix/cytology , Female , Hodgkin Disease/metabolism , Humans , Immunohistochemistry , Lymphoid Tissue/metabolism , Lymphoma, Non-Hodgkin/metabolism , Membrane Glycoproteins/immunology , Neoplasms/pathology , Tumor Cells, Cultured
6.
Histopathology ; 15(5): 461-71, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2599510

ABSTRACT

The AMeX method (cold Acetone fixation with subsequent Methyl benzoate and Xylene treatment and routine paraffin embedding) has been recently revived for simultaneous preservation of morphology of cells and their antigens. We propose a modification of this method (ModAMeX), with the use of proteolytic enzyme inhibitors and low temperature paraffin wax embedding, which results in better preservation of a large number of leucocyte differentiation antigens and diagnostic morphologic detail. T-cell antigens (CD1, CD2, CD3, CD7 & CD8), B-cell antigens (CD22), macrophage associated antigens (CD11c, CD14 and others), activation antigens (CD25 and others), as well as some other antigens of diagnostic interest (CD10) were found to be preserved with a staining intensity equal to that of sections of fresh frozen tissue. Although the staining intensity of other T-cell antigens (CD4 & CD5), B-cell antigens (CD19, CD21 & CD37), activation antigens (Ki-1) and nuclear proliferation antigen (Ki-67) was slightly weaker as compared with frozen sections, this could be corrected by increasing the monoclonal antibody concentration. Staining for heavy and light chains of immunoglobulins was minor, sometimes compromised due to persistence of background staining as a result of extracellular immunoglobulins. The ModAMeX method has the advantages of simplicity, low cost and the possibility of exchange of tissue material between laboratories.


Subject(s)
Antigens, Differentiation , Immunohistochemistry/methods , Leukocytes/immunology , Acetone , Antibodies, Monoclonal , Benzoates , Fixatives , Humans , Lymphoma/immunology , Lymphoma/pathology , Paraffin , Protease Inhibitors , Xylenes
SELECTION OF CITATIONS
SEARCH DETAIL