Within the framework of the EURADOS Working Group 11, a comparison of passive neutron dosemeters in high-energy neutron fields was organised in 2011. The aim of the exercise was to evaluate the ...response of poly-allyl-glycol-carbonate neutron dosemeters from various European dosimetry laboratories to high-energy neutron fields. Irradiations were performed at the iThemba LABS facility in South Africa with neutrons having energies up to 66 and 100 MeV.
The outcome of advanced ovarian cancer patients has not significantly improved since the introduction of platinum. One of the major reasons for this failure is the lack of an effective second-line ...treatment. In this phase II trial we tested the combination of gemcitabine and etoposide in 2 different groups of patients. Group 1 consisted of patients showing disease progression or relapse within 6 months of first-line platinum-based chemotherapy. Group 2 comprised heavily pretreated patients showing progression during the last chemotherapy attempt.
Thirty-four patients were enrolled. Gemcitabine was administered at a dose of 1,000 mg/m(2) on days 1 and 8 and etoposide was administered orally at 100 mg/day on days 8-12 for 6 courses.
Eighteen patients (52.9%) had an objective response and the median duration of the response was 10.3 months. Our chemotherapy regimen showed a low toxicity and good patient compliance. In 5 patients the treatment had to be delayed and in only 2 patients it was discontinued.
The combination of gemcitabine and oral etoposide seems to be a safe and effective second-line treatment for platinum-resistant ovarian cancer patients. Additional data on larger series are warranted to better define the activity of this combination regimen.
In order to identify early clinical features and survival predictors of supranuclear palsy (PSP) and multiple system atrophy (MSA), we compared the disease course of patients consecutively referred ...between 1987 and 1999 and followed to December 1999. Thirty-nine PSP and 74 MSA patients were diagnosed according to commonly accepted clinical criteria. Length of survival was ascertained from death certificates or by contacting relatives. Ten-year survival after disease onset was 29% for both disorders. Median survival was 7.0 years (PSP) and 7.5 (MSA). Neither age, symptoms at onset, or disability at diagnosis predicted survival. At diagnosis, all PSP patients had oculomotor palsy, whereas 89% of MSA patients had dysautonomia; bradykinesia and falls were the most frequent common signs. Distinctive early signs were palilalia, cognitive impairment and hyperreflexia in PSP; hypophonia, anterocollis and dysautonomia in MSA. MSA patients responded better to levodopa. Attention to early distinctive features can improve differential diagnosis and inform subsequent management.
Bonner sphere spectrometers (BSS) are being used widely in neutron spectrometry since 1960. The response to neutrons of these moderating detectors spans over a broad energy range. This work discusses ...the measurement of the sensitivity of an extended range BSS hosting a CR39 nuclear track detector coupled to a boron converter. Two kinds of boron converters were tested, the first made by natural boron and a second one enriched in 10B. The BSS response functions were calculated with Monte Carlo simulation using the MCNPX 2.4.0. and the FLUKA codes.
In human Burkitt's Lymphoma (BL) BRG cells, a t(8;14) translocation, placing c-myc near the Eμ enhancer of the H chain locus, causes tumor expansion. Earlier, we showed that a peptide nucleic acid ...complementary to the Eμ sequence (PNAEμ), specifically inhibited the expression of translocated c-myc and impaired the growth of BRG cells-induced subcutaneous tumors in mice suffering from severe combined immunodeficiency (SCID). In this study, the therapeutic potential of PANAEμ was evaluated in a systemic mouse model. BRG-BL cells transfected with the luciferase gene were inoculated intravenously into SCID mice resulting in a preferential expansion, similar to the one of human adult patients, in the abdominal cavity, central nervous system and bone marrow. The mice were chronically injected intraperitoneally either with PANAEμ or with control PNA. The treatment was stopped when the control animals developed severe neurological symptoms. As detected both by inspection at necropsy and imaging, overall tumor growth in PNAEIA-treated mice decreased by >80%. Histological and immunohistochemical studies showed, only in PANAEμ-treated mice, a substantially reduced BL cell growth at the major sites of invasion and vast areas of necrosis in the lymphomatous tissues, with concomitant c-myc expression downregulation. Altogether, the data support the therapeutic potential of PNAEμ in human adult BL. doi:10.1038/cgt.2009.26; published online 10 April 2009 Keywords: Burkitt's lymphoma; animal model; anti-gene therapy; peptide nucleic acids; Ey enhancer
In human Burkitt's Lymphoma (BL) BRG cells, a t(8;14) translocation, placing c-myc near the Emu enhancer of the H chain locus, causes tumor expansion. Earlier, we showed that a peptide nucleic acid ...complementary to the Emu sequence (PNAEmu), specifically inhibited the expression of translocated c-myc and impaired the growth of BRG cells-induced subcutaneous tumors in mice suffering from severe combined immunodeficiency (SCID). In this study, the therapeutic potential of PNAEmu was evaluated in a systemic mouse model. BRG-BL cells transfected with the luciferase gene were inoculated intravenously into SCID mice resulting in a preferential expansion, similar to the one of human adult patients, in the abdominal cavity, central nervous system and bone marrow. The mice were chronically injected intraperitoneally either with PNAEmu or with control PNA. The treatment was stopped when the control animals developed severe neurological symptoms. As detected both by inspection at necropsy and imaging, overall tumor growth in PNAEmu-treated mice decreased by >80%. Histological and immunohistochemical studies showed, only in PNAEmu-treated mice, a substantially reduced BL cell growth at the major sites of invasion and vast areas of necrosis in the lymphomatous tissues, with concomitant c-myc expression downregulation. Altogether, the data support the therapeutic potential of PNAEmu in human adult BL.
Previous studies suggest that the diversity of the expressed variable (V) region repertoire of the immunoglobulin (Ig)H chain of B-CLL cells is restricted. Although limited examples of marked ...constraint in the primary structure of the H and L chain V regions exist, the possibility that this level of restriction is a general principle in this disease has not been accepted. This report describes five sets of patients, mostly with unmutated or minimally mutated IgV genes, with strikingly similar B cell antigen receptors (BCRs) arising from the use of common H and L chain V region gene segments that share CDR3 structural features such as length, amino acid composition, and unique amino acid residues at recombination junctions. Thus, a much more striking degree of structural restriction of the entire BCR and a much higher frequency of receptor sharing exists among patients than appreciated previously. The data imply that either a significant fraction of B-CLL cells was selected by a limited set of antigenic epitopes at some point in their development and/or that they derive from a distinct B cell subpopulation with limited Ig V region diversity. These shared, stereotyped Ig molecules may be valuable probes for antigen identification and important targets for cross-reactive idiotypic therapy.
Hepatocyte growth factor, produced by stromal and follicular dendritic cells, and present at high concentrations in the sera of patients with chronic lymphocytic leukemia, prolongs the survival of ...leukemic B cells by interacting with their receptor, c-MET. It is, however, unknown whether hepatocyte growth factor influences microenvironmental cells, such as nurse-like cells, which deliver survival signals to the leukemic clone. We evaluated the expression of c-MET on nurse-like cells and monocytes from patients with chronic lymphocytic leukemia and searched for phenotypic/functional features supposed to be influenced by the hepatocyte growth factor/c-MET interaction. c-MET is expressed at high levels on nurse-like cells and at significantly higher levels than normal on monocytes from patients. Moreover, the hepatocyte growth factor/c-MET interaction activates STAT3(TYR705) phosphorylation in nurse-like cells. Indoleamine 2,3-dioxygenase, an enzyme modulating T-cell proliferation and induced on normal monocytes after hepatocyte growth factor treatment, was detected together with interleukin-10 on nurse-like cells, and on freshly-prepared patients' monocytes. Immunohistochemical/immunostaining analyses demonstrated the presence of c-MET(+) and indoleamine 2,3-dioxygenase(+) cells in lymph node biopsies, co-expressed with CD68 and vimentin. Furthermore nurse-like cells and chronic lymphocytic monocytes significantly inhibited T-cell proliferation, prevented by anti-transforming growth factor beta and interleukin-10 antibodies and indoleamine 2,3-dioxygenase inhibitors, and supported CD4(+)CD25(high+)/FOXP3(+) T regulatory cell expansion. We suggest that nurse-like cells display features of immunosuppressive type 2 macrophages: higher hepatocyte growth factor levels, produced by leukemic or other microenvironmental surrounding cells, may cooperate to induce M2 polarization. Hepatocyte growth factor may thus have a dual pathophysiological role: directly through enhancement of survival of the leukemic clone and indirectly by favoring T-cell immunosuppression.
PDF
