In Canada, there are legal provisions called Dangerous Offender and Long-Term Offender designations available to apply severe restrictions on individual liberties for persons who engage in serious ...offenses (often repetitive) and who pose a substantial risk for violence. Since establishing the presence of a risk for violence is central to decision making in these cases, an evaluator's violence risk assessment (VRA) and expert witness testimony play a vital role in hearings for these offenders. The present study examined judicial decisions regarding expert evidence on VRAs submitted to the court in 214 Dangerous Offender/Long-Term Offender hearings identified through the Canadian Legal Information Institute database. Written judicial decisions were analyzed for any comments regarding factors related to expert evidence on VRA. The commonalities that were identified, including qualities of (a) the evaluators, (b) the VRAs completed, and (c) the evaluators' expert testimony about VRA, offer key considerations for professionals working in the mental health and criminal justice fields. They may also contribute to the development of guidelines for professionals conducting VRA used by courts.
Public Significance Statement
Judicial decisions in Canadian courts provide insights to judges, lawyers, and threat assessment professionals conducting violence risk assessments regarding (VRA) what may be important to include in cases involving violence risk and management evidence before the court. This study offers some guidance on what courts raise regarding how evaluators can (a) demonstrate that they have appropriate qualifications to conduct the VRA, (b) demonstrate their knowledge of and rationale for the sources and methods of the assessment they conduct, and (c) provide effective expert testimony in court.
Ovarian cancer is the most lethal gynecological malignancy, with typically late diagnosis. Altered DNA methylation of tumor suppressor gene promoters probably plays a relevant role in ovarian ...carcinogenesis and frequently occurs as an early event in the development of different types of cancer including ovarian carcinoma. GATA4 methylation has been reported in a variety of human cancers. The aim of this study was to investigate promoter methylation of the GATA4 gene in ovarian cancer by comparison with that in normal ovarian tissue.
To search for promoter methylation of the GATA4 gene we used MSP (methylation-specific PCR) to compare the methylation status in 67 tissue samples of ovarian cancer with that in 40 control samples.
In our study, methylation-specific PCR revealed GATA4 promoter methylation in 21 of 67 specimens with ovarian cancer (31.3%), and in none of the control ovarian tissue samples.
These results confirm that methylation in the GATA4 promoter region could play an important role in ovarian carcinogenesis, and show new loci which are highly methylated only in ovarian cancer samples and which are associated predominantly with the endometrioid type of ovarian carcinoma.
Transmissive spongiform encephalopathies (TSE) are neurodegenerative diseases characterized by depositions of abnormally folded prion protein (PrP
TSE
) in brain. PrP
TSE
is at present the only ...specific biochemical marker of human and animal TSE. As deposits of PrP
TSE
remain in the body for long periods, there is substantial chance of them being nonenzymatically modified by glycation. The detection of glycated PrP
TSE
may have potential to serve as a diagnostic marker. Monoclonal antibodies specific for carboxymethyl lysine/arginine-modified prion protein were prepared. Recombinant human prion protein (rhPrP) was bacterially expressed and purified by affinity chromatography. rhPrP was modified by glyoxylic acid that introduces carboxymethyl groups on lysine and arginine residues present within the molecule of the protein. Modified rhPrP (rhPrP-CML) was used for immunization of 6 mice, and 960 hybridoma cells were prepared. Screening of cell supernatants resulted in the selection of four promising clones. One of them (EM-31) strongly reacts with human and mouse recombinant PrP-CML, and three other clones react also with CML in vitro modified human and mouse brain PrP. Besides possible implication in TSE diagnostics, the antibodies may serve as tolls to advance our knowledge regarding the role of glycation in the prion pathophysiology.
Abstract 2032
Cellular prion protein (PrPc) plays a key role in pathogenesis of prion diseases, however, its physiologic function remains unclear. The involvement of PrPc in hematopoiesis was ...suggested by importance of its expression for self renewal and survival of long term repopulating hematopoietic stem cells. Prion diseases were shown to deregulate transcription of several erythroid genes and we have demonstrated reduction of erythroid cell and erythropoietin production in FVB PrP-/- (Zurich I) mice in response to acute anemia (Zivny J. et al. Blood Cells Mol Dis. 2008;40:302-307). In this study, we exploited different mouse models with manipulated level of PrPc expression to verify the role of PrPc in erythropoiesis. First set of experiments was carried out on PrP-/- (Zurich I) and Tga20 PrP over-expressing mice on a mixed C57Bl6/129Sv genetic background. Inbred C57Bl6 mice served as a wild type control (WT). Induction of acute anemia by phenylhydrazine (PHZ) in PrP-/- and WT mice (n=18) led to drop in the hematocrit (HCT) from 52.5±1.5 and 49.8±2.5% to 37.9± 1.0 and 41.9±3.0% after 24 h, respectively. The course of anemia was significantly deeper in PrP-/- mice at 72 h, 96 h and 120 h (p < 0.01) after PHZ administration. Plasma levels of erythropoietin (Epo) in response to anemia reached higher maximum levels in PrP-/- than WT mice (2250 vs. 1810 pg/mL) although rose more slowly. The level of Epo mRNA in kidneys increased approximately 30-fold in both, WT and PrP-/- mice, however, in WT mice peaked at 24 h whereas in KO mice at 96 h. We repeated the study with smaller groups of PrP-/- and Tga20 mice (n=9) and analysed samples 24 h and 96 h post anemia induction. Random PrP gene re-introduction in Tga20 mice rescued the animals from severe anemia. Decrease in HCT after PHZ administration was significantly lower in Tga20 comparing to PrP-/- mice and was accompanied by less elevated reticulocyte (RTC) count, plasma Epo level and level of Epo mRNA in kidneys. Next we studied the dynamics of unchallenged erythropoiesis in PrP-/-, Tga20 and WT mice by in vivo labelling of blood cells with NHS-biotin and subsequent flow cytometric analysis of relative numbers of newly produced non-labelled RBC. WT mice had significantly enhanced turnover of RBC with higher counts of non-labelled RBC comparing to PrP-/- during 46 days of chase (p < 0.05). Half- life of labeled RBC in WT mice was 20 days, but 32 and 30 days in PrP-/- and Tga20 mice, respectively. Tga20 mice displayed tendency to increased RBC turnover over PrP-/- mice, but the difference was significant only 2 and 33 days after initiation of the experiment. Having in mind possible limitations of experiments conducted in genetically modified inbred mice we have designed second set of experiments in more stringent animal models. We mated C57Bl6/129Sv PrP-/- mice with inbred C57Bl6 and outbred CD-1 mice. Heterozygotes in F1 generation were mated and their PrP -/-, PrP -/+ and PrP +/+ offspring used in the experiments. Anemia was induced by PHZ and blood was sampled from tail vein at defined time points and HCT and RTC count were analysed. In C57Bl6 crossbreeds we observed significantly higher starting HCT level in PrP-/- mice (p < 0.05) compared to PrP-/+ and PrP+/+ mice reaching 53.2±2.3, 50.0±2.1 and 49±2.9%, respectively. Similar decrease in HCT was observed for all PrP groups 24 h after PHZ administration, however, significant differences between PrP-/- and PrP+/+ mice were recorded at 48 h and 72 h. The recovery to normal HCT was again retarded in PrP-/- mice. RTC counts rose more rapidly in PrP+/+ mice after PHZ administration and declined to basal levels faster than in PrP-/- mice, the difference reached significance at 24 h, 48 h and 96 h. Dynamics of unchallenged erythropoiesis in C57Bl6 crossbreeds was similar in all three PrP genotypes with no significant differences in numbers of newly produced RBC during 57 days of the experiment. In CD-1 crossbreed mice no significant differences in HCT and RTC counts were detected after PHZ induced anemia among PrP-/-, PrP-/+ and PrP+/+ siblings. Also the dynamics of unchallenged erythropoiesis was similar in all PrP genotypes. To sum up, our data confirmed the role of PrPc in stress erythropoiesis in studied inbred mouse models. In outbred model the effect of PrP deletion on erythropoiesis seems to be compensated. (GACR310/08/0878, GAUK86408)
No relevant conflicts of interest to declare.
The accumulation of the misfolded forms of cellular prion protein, i.e. prions (PrPSc), in the brain is one of the crucial characteristics of fatal neurodegenerative disorders, called transmissible ...spongiform encephalopathies (TSEs). Cellular prion protein is normally linked to the cell surface by the glycosylphosphatidylinositol (GPI) anchor. There is accumulating evidence that the GPI-anchorless prion protein may act as an accelerator of formation and propagation of prions. In the TSE affected human brain we have previously discovered a novel GPI-anchorless prion protein fragment, named PrP226*, which ends with the tyrosine 226. This fragment can be labeled specifically by the monoclonal antibody V5B2.
We developed a DELFIA based assay for quick and sensitive detection of the PrP226* fragment in human brain tissue homogenates. By calculating the ratio between the signals of native (N) and denatured (D) samples applied to the assay we were able to observe significant difference between 24 TSE affected brains and 10 control brains. The presence of PrP226* in brain tissue was confirmed by western blot.
Our results demonstrate that PrP226* is present in small quantities in healthy human brain, whereas in degenerated brain it accumulates in prion aggregates, proportionally to PrPSc. Samples with high D/N ratio generally comprised more proteinase K resistant PrP, while no correlation was found between the quantity of PrP226* and standard classification of Creutzfeldt-Jakob disease (CJD).
In the present study we show that the PrP226* fragment accumulates in prion aggregates and after being released from them by a denaturation procedure, could serve as a proteinase K digestion independent biomarker for human TSEs. The PrP226* assay described in this paper offers a tool to follow and study this unique anchorless PrP fragment in various parts of human brain and possibly also in other tissues and body fluids.
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