References of "de Leval, Laurence"
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See detailCd28-B7 Costimulatory Blockade by Ctla4ig Delays the Development of Retrovirus-Induced Murine Aids
de Leval, Laurence ULg; Colombi, S.; Debrus, S. et al

in Journal of Virology (1998), 72(6), 5285-90

Mouse AIDS (MAIDS) induced in C57BL/6 mice by infection with a replication-defective retrovirus (Du5H) combines extensive lymphoproliferation and profound immunodeficiency. Although B cells are the main ... [more ▼]

Mouse AIDS (MAIDS) induced in C57BL/6 mice by infection with a replication-defective retrovirus (Du5H) combines extensive lymphoproliferation and profound immunodeficiency. Although B cells are the main target of viral infection, recent research has focused on CD4(+) T cells, the activation of which is a key event in MAIDS induction and progression. A preliminary observation of increased expression of B7 molecules on B cells in MAIDS prompted us to address the possible involvement of the CD28/B7 costimulatory pathway in MAIDS. Mice infected with the MAIDS-inducing viral preparation were treated with murine fusion protein CTLA4Ig (3 x 50 microg/week given intraperitoneally), a competitive inhibitor of physiological CD28-B7 interactions. In CTLA4Ig-treated animals, the onset of the disease was delayed, lymphoproliferation progressed at a much slower rate than in untreated mice, and the loss of in vitro responsiveness to mitogens was reduced. Relative expression of Du5H did not differ between treated and untreated animals. These results suggest that the CD28/B7 costimulatory pathway contributes to MAIDS development. [less ▲]

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See detailThrombangiitis Obliterans (Buerger's Disease): Still a Limb Threatening Disease
VAN DAMME, Hendrik ULg; de Leval, Laurence ULg; CREEMERS, Etienne ULg et al

in Acta Chirurgica Belgica (1997), 97(5), 229-36

A series of 29 well-documented and properly analysed patients with thrombangiitis obliterans (Buerger's disease) is presented. The diagnosis of Buerger's disease was based on following criteria: smoking ... [more ▼]

A series of 29 well-documented and properly analysed patients with thrombangiitis obliterans (Buerger's disease) is presented. The diagnosis of Buerger's disease was based on following criteria: smoking history, onset before the age of 50 years, infrapopliteal arterial occlusive disease, either upper limb involvement or phlebitis migrans, absence of atherosclerotic risk factors other than smoking. In the last 10 years (1986-1996), we identified 29 patients who met these rigid criteria. There were 24 men and 5 women, aged 32.4 years at the moment of the disease first clinical symptom. The cumulative tobacco use averaged 16 pack-years for each patient. The initial symptom was limited gangrene of a toe (n = 9) or a finger (n = 2), foot claudication (n = 6), calf claudication (n = 3), rest pain (n = 3), migratory superficial phlebitis (n = 4), and Raynaud phenomenon (n = 2). Angiography and/or Doppler ultrasound revealed digital, pedal and calf artery involvement in all patients, with proximal extension in ten patients (femoropopliteal in ten, including three cases with external iliac artery involvement). Seven patients had also evidence of upper limb involvement. Histologic proof was available in only seven patients. Only nine patients completely stopped smoking. Treatment was exclusively medical in five cases. Twenty-four underwent sympathectomy (20 at lumbar, and four at thoracic level), with good immediate result in 16. In 11 patients a vascular reconstruction was done (eight femorocrural and three iliofemoral bypasses), with a patency rate of only 36% at two years. Amputation was required in 16 patients (a mean of 2.7 amputations per patient) at one or more levels: toe (n = 19), forefoot (n = 5), below knee (n = 8), above knee (n = 2), finger (n = 3). Two patients ended up with bilateral leg amputation. Overall, 23% (7/30) of the patients required major leg amputation during the course of the disease. Disease progression was moderately related to continued tobacco use. Buerger's disease still entails considerable risk of major amputation. Complete abstinence from tobacco use is crucial to expect stabilization of the process. However, in advanced stages of the disease and despite cessation of smoking recurrent episodes of ischaemia or tissue loss are not excluded. [less ▲]

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See detailPeyer's Patches in Murine Aids: Dissociation between Lymphoproliferation and Anergy
Colombi, S.; Moutschen, Michel ULg; de Leval, Laurence ULg et al

in Scandinavian Journal of Immunology (1997), 45(2), 175-81

RadLV-Rs infection induces a murine immunodeficiency syndrome associated with a dramatic enlargement of spleen and lymph nodes. Surprisingly, the lymphoproliferation excludes thymus and Peyer's patches ... [more ▼]

RadLV-Rs infection induces a murine immunodeficiency syndrome associated with a dramatic enlargement of spleen and lymph nodes. Surprisingly, the lymphoproliferation excludes thymus and Peyer's patches (PP). To understand the cellular interactions underlying lymphoproliferation further, the authors investigated the fate of PP in RadLV-Rs infected mice. The atrophy of PP was mostly due to the depletion of B cells, while the proportion of CD4+ and CD8+ T cells was increased. Nevertheless, B cell phenotype was modified with the emergence of lymphocytes with a low expression of B220 in infected PP. T cells characterized by a memory/activated phenotype in control PP did not undergo phenotypical changes after viral infection (i.e. regarding Thy-1 and CD44 expression). Despite the absence of lymphoproliferation, PP T and B cells displayed altered responses to mitogens in vitro. Finally, alterations of the expression of adhesion molecules and vascular addressins could not explain the atrophy of PP by a reduced homing to this lymphoid site. B cells and T cells from normal PP are clearly different from lymph nodes (LN) lymphocytes. The authors propose that the particular functional state which characterizes PP lymphocytes influences the B cell/T cell crosstalk necessary for RadLV-Rs-induced lymphoproliferation. [less ▲]

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See detailIndependent value of the 67-kilodalton laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

Conference (1997, January 17)

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See detailFatal Massive Liver Steatosis. A Clinicopathological Case Report
de Leval, Laurence ULg; Lambermont, Bernard ULg; D'Orio, Vincenzo ULg et al

in Acta Gastro-Enterologica Belgica (1997), 60(2, Apr-Jun), 180-183

Hepatic fatty change is a common lesion. Two forms are recognized: micro- and macrovesicular steatosis, the former being much less frequent and more serious than the latter. The case of an alcoholic woman ... [more ▼]

Hepatic fatty change is a common lesion. Two forms are recognized: micro- and macrovesicular steatosis, the former being much less frequent and more serious than the latter. The case of an alcoholic woman under anticonvulsivant therapy and with medications for a syndrome of inappropriate secretion of antidiuretic hormone (SIADH) who presented with rapidly progressive cholestasis and hepatocellular failure is reported. Massive macro- and micro-vesicular hepatic steatosis was diagnosed at autopsy. The authors review the clinico-pathological features associated with this condition, and causal factors possibly implicated in this case are discussed in regard with currently considered pathophysiological mechanisms. [less ▲]

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See detailOverexpression of the 67-kD laminin receptor correlates with tumor progression in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in Proceedings of the American Association for Cancer Research (1997), 38

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See detailIndependent prognostic value of the 67-kD laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in British Journal of Urology (1997), 80(Suppl. 2), 231

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See detailIndependent value of the 67-kilodalton laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in Acta Clinica Belgica (1997), 52(2), 93

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See detailIndependent prognostic value of the 67-kd laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Menard, Sylvie et al

in Journal of the National Cancer Institute (1997), 89(16), 1224-7

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See detailOverexpression of the 67-kDa laminin receptor correlates with tumor progression in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in Clinical & Experimental Metastasis (1996, March), 14(Suppl. 1), 1996

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See detailMorphological Changes of Thymus in Retrovirus-Induced Murine Acquired Immunodeficiency Syndrome (Maids)
de Leval, Laurence ULg; Deprez, Manuel ULg; Colombi, S. et al

in Pathology - Research & Practice (1995), 191(6), 506-12

The possible contribution of the thymus in the setting of acquired immunodeficiencies is still questioned. Here we report some new findings regarding a potential involvement of the thymus in mice infected ... [more ▼]

The possible contribution of the thymus in the setting of acquired immunodeficiencies is still questioned. Here we report some new findings regarding a potential involvement of the thymus in mice infected with RadLV-Rs, a viral mixture inducing murine acquired immunodeficiency syndrome (MAIDS). Thymi were sequentially removed, weighted and morphologically analyzed at different time intervals post-infection. Infection with RadLV-Rs led to a decrease in thymus weight mostly apparent from the fourth week. The first changes were seen at the third week as perivascular clusters of B-cells at the cortico-medullary junction. The ensuing process of atrophy mainly involved the cortex, while a mixed population of large T- and B-cells filled the medulla. These observations are discussed with regard to the pathological changes occurring in other lymphoid and non-lymphoid organs, in the context of the lymphoproliferation and immunodeficiency characterizing the disease, and by comparison with other models of retrovirus-induced immunodeficiencies. [less ▲]

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See detailFlow cytometry in prostate cancer: Histological and clinical correlation
de Leval, Laurence ULg; Waltregny, David ULg; Greimers, Roland ULg et al

in Acta Urologica Belgica (1994), 62(1), 37-43

DNA histograms were obtained by flow cytometry for 39 human prostate carcinomas (27 total prostatectomy specimens, 5 biopsies and 7 transuretral resections). The study was performed on formalin-fixed and ... [more ▼]

DNA histograms were obtained by flow cytometry for 39 human prostate carcinomas (27 total prostatectomy specimens, 5 biopsies and 7 transuretral resections). The study was performed on formalin-fixed and paraffin-embedded material. In this report, ploidy index did not seem to be a good marker of prognosis as no significant variation in ploidy was found neither among the different stages nor among the different Gleason categories. Proliferative index of the tumors seemed to be a more sensitive parameter; a significant relation was observed between proliferative index and stage of the tumor. The authors discuss these results under the light of previously reported observations. [less ▲]

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See detailCytofluorometric analysis of prostate cancer specimens: Histological and clinical correlations
de Leval, Laurence ULg; Waltregny, David ULg; Greimers, Roland ULg et al

in Acta Urologica Belgica (1994, January), 62

DNA histograms were oblained by flow cytometry for 39 human prostate carcinomas (27 total proslatectomy specimens, 5 biopsies and 7 transuretral resections). The study was performed on formalin-fixed and ... [more ▼]

DNA histograms were oblained by flow cytometry for 39 human prostate carcinomas (27 total proslatectomy specimens, 5 biopsies and 7 transuretral resections). The study was performed on formalin-fixed and paraffin-embedded. material. In this report, ploidy index did not seem to be a good marker of prognosis as no significant variation in ploidy was found neither among the different stages nor among the different Gleason categories. Proliferative index of the tumors seemed to be a more sensitive parameter; a significant relation was observed between proliferative index and stage of the tumor. The authors discuss these results under the light of previously reported observations. [less ▲]

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See detailThymus Involvement in Murine Acquired Immunodeficiency (Maids)
Colombi, Sonia; Deprez, Manuel ULg; de Leval, Laurence ULg et al

in Thymus (1994), 23(1), 27-37

Due to self-renewal of the peripheral pool of T-cells, adult thymectomy has normally little influence on immunocompetence. However, thymus might play a more important role in the setting of viral-induced ... [more ▼]

Due to self-renewal of the peripheral pool of T-cells, adult thymectomy has normally little influence on immunocompetence. However, thymus might play a more important role in the setting of viral-induced cytopathic effects on T-cells in the periphery. Therefore, thymus weight, cell numbers, and subset distribution were sequentially analysed after infection with RadLV-Rs, a viral mixture known to induce murine retrovirus induced immunodeficiency (MAIDS). Infection induced thymic atrophy (concerning organ weight as well as total cell number) which culminated seven weeks after inoculation. The atrophic process mostly reflected the depletion of double positive CD4+ CD8+ cells since their proportion sharply decreased around week 6. Single positive T-cells were less affected by the process. The proportion of B-cells progressively increased. Surprisingly, there was a strong correlation between the extent of atrophy and the frequency of B-cells in the thymus. Finally, an abnormal CD4+ T-cell subset lacking Thy-1 and previously described in the periphery also appeared in the thymus and its frequency was strongly correlated with the expansion of B-cells in this organ. [less ▲]

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See detailAnevrysme femoral superficiel rompu dans le cadre d'une neurofibromatose. A propos d'un cas
Van Damme, Hendrik ULg; Deprez, Manuel ULg; De Leval, Laurence ULg et al

in Journal des Maladies Vasculaires (1994), 19(1), 62-5

The authors observed the spontaneous rupture of a dysplastic superficial femoral artery in a 47 years old patient with Von Recklinghausen disease. The patient presents a gigantism of his right lower limb ... [more ▼]

The authors observed the spontaneous rupture of a dysplastic superficial femoral artery in a 47 years old patient with Von Recklinghausen disease. The patient presents a gigantism of his right lower limb. On angiography, the femoropopliteal axis is polyaneurysmal and there is evidence of rupture at mid-thigh. The diseased artery is excluded by interposition of a dacron prosthesis, with reimplantation of the deep femoral artery. Histology shows fibrohyalin thickening of the intima. Dysplasia of large limb arteries is excessively rare in Von Recklinghausen disease. [less ▲]

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See detailInfluence of laminin or fibroblasts upon colony formation in the mouse by B16 melanoma cell spheroids: a morphometric analysis.
Coucke, P.; de Leval, Laurence ULg; Leyh, P. et al

in In Vivo (Athens, Greece) (1992), 6(2), 119-24

By microscopical observation and using an original morphometric method, we analyzed on histological sections the rate of lung colony formation after the intravenous injection into the mouse of B16 ... [more ▼]

By microscopical observation and using an original morphometric method, we analyzed on histological sections the rate of lung colony formation after the intravenous injection into the mouse of B16 melanoma cells previously cultivated in vitro as aggregates. After the injection of B16 pure spheroids, superficial lung colonies were more numerous than internal lung colonies. After the injection of mixed spheroids (B16 + 3T3 fibroblasts), the size of colony sections was increased. Addition of laminin to pure or mixed spheroids decreased the size of colony sections but increased the number of internal lung colonies. [less ▲]

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See detailFibronectin Promotes Lung Colony Formation in the Mouse by B16 Melanoma Cells Spheroids
Coucke, P.; Gillet, Marie-Claire ULg; de Leval, Laurence ULg et al

in In Vivo (Athens, Greece) (1992), 6(5, Sep-Oct), 481-6

By microscopical observation and using an original method of automatic image analysis, we studied on histological sections the rate of lung colony formation after intravenous injection into the mouse of ... [more ▼]

By microscopical observation and using an original method of automatic image analysis, we studied on histological sections the rate of lung colony formation after intravenous injection into the mouse of B16 melanoma cells previously cultivated in vitro as pure or mixed spheroids (B16 + 3T3 fibroblasts). The preincubation in vitro of pure spheroids with fibronectin significantly increased the percentages of lung section area occupied by tumors and the relative number of internal lung colonies. This effect of fibronectin was even more obvious when mixed spheroids were injected. [less ▲]

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