No Evidence of BRCA1/2 genomic rearrangements in high-risk French-Canadian breast/ovarian cancer families

The discovery of deleterious mutations in the breast and ovarian cancer susceptibility genes, BRCA1 and BRCA2, has facilitated the identification of individuals at particularly high risk of these diseases. There is a wide variation between populations in the prevalence and related risks of various types of BRCA1/2 mutations, so estimates cannot be extrapolated to Canadians, especially not founder populations such as French- Canadians. Polymerase chain reaction (PCR)-based methods were used to detect the majority of these mutations. These approaches usually failed to detect large DNA rearrangements, which have been claimed to be involved in other populations in 5% to up to 36% of BRCA1-positive families. There is very little information about the contribution of this type of mutation in BRCA2-positive families. To investigate if our available mutation spectrum of BRCA1 and BRCA2 in high-risk French-Canadian breast/ovarian cancer families has been biased by PCR-based direct sequencing methods, we first used Southern blot analysis to test DNA samples from 61 affected/obligate carrier individuals from 58 families in which no BRCA1/2 deleterious mutation was found. Finally, 154 individuals from 135 BRCA1/2 nonconclusive families, including all those tested previously by Southern blot analysis, were tested with the new multiplex ligation probe amplification (MLPA) technique. These approaches failed to detect any rearrangement. Moreover, if the frequency of MLPA-detectable rearrangements in our cohort of 135 BRCA1/2 nonconclusive families was 2.2% or higher, we would have had a 95% or greater chance of observing at least one such rearrangement. As no rearrangements were identified, such large rearrangements must be quite rare in our population.     

Plasma lipid profiling across species for the identification of optimal animal models of human dyslipidemia

In an attempt to understand the applicability of various animal models to dyslipidemia in humans and to identify improved preclinical models for target discovery and validation for dyslipidemia, we measured comprehensive plasma lipid profiles in 24 models. These included five mouse strains, six other nonprimate species, and four nonhuman primate (NHP) species, and both healthy animals and animals with metabolic disorders. Dyslipidemic humans were assessed by the same measures. Plasma lipoprotein profiles, eight major plasma lipid fractions, and FA compositions within these lipid fractions were compared both qualitatively and quantitatively across the species. Given the importance of statins in decreasing plasma low-density lipoprotein cholesterol for treatment of dyslipidemia in humans, the responses of these measures to simvastatin treatment were also assessed for each species and compared with dyslipidemic humans. NHPs, followed by dog, were the models that demonstrated closest overall match to dyslipidemic humans. For the subset of the dyslipidemic population with high plasma triglyceride levels, the data also pointed to hamster and db/db mouse as representative models for practical use in target validation. Most traditional models, including rabbit, Zucker diabetic fatty rat, and the majority of mouse models, did not demonstrate overall similarity to dyslipidemic humans in this study.     

Voltage-dependent-anion-channels (VDACs) in Arabidopsis have a dual localization in the cell but show a distinct role in mitochondria

In mammals, the Voltage-dependent anion channels (VDACs) are predominant proteins of the outer mitochondrial membrane (OMM) where they contribute to the exchange of small metabolites essential for respiration. They were shown to be as well associated with the plasma membrane (PM) and act as redox enzyme or are involved in ATP release for example. In Arabidopsis, we show that four out of six genomic sequences encode AtVDAC proteins. All four AtVDACs are ubiquitously expressed in the plant but each of them displays a specific expression pattern in root cell types. Using two complementary approaches, we demonstrate conclusively that the four expressed AtVDACs are targeted to both mitochondria and plasma membrane but in differential abundance, AtVDAC3 being the most abundant in PM, and conversely, AtVDAC4 almost exclusively associated with mitochondria. These are the first plant proteins to be shown to reside in both these two membranes. To investigate a putative function of AtVDACs, we analyzed T-DNA insertion lines in each of the corresponding genes. Knock-out mutants for AtVDAC1, AtVDAC2 and AtVDAC4 present slow growth, reduced fertility and yellow spots in leaves when atvdac3 does not show any visible difference compared to wildtype plants. Analyses of atvdac1 and atvdac4 reveal that yellow areas correspond to necrosis and the mitochondria are swollen in these two mutants. All these results suggest that, in spite of a localization in plasma membrane for three of them, AtVDAC1, AtVDAC2 and AtVDAC4 have a main function in mitochondria.     

The effect of prolyl oligopeptidase inhibition on extracellular acetylcholine and dopamine levels in the rat striatum

Prolyl oligopeptidase (PREP, EC 3.4.21.26) inhibitors have potential as cognition enhancers, but the mechanism of action behind the cognitive effects remains unclear. Since acetylcholine (ACh) and dopamine (DA) are known to be associated with the regulation of cognitive processes, we investigated the effects of two PREP inhibitors on the extracellular levels of ACh and DA in the rat striatum using in vivo microdialysis. KYP-2047 and JTP-4819 were administered either as a single systemic dose (50 μmol/kg～17 mg/kg i.p.) or directly into the striatum by retrodialysis via the microdialysis probe (12.5, 37.5 or 125 μM at 1.5 μl/min for 60 min). PREP inhibitors had no significant effect on striatal DA levels after systemic administration. JTP-4819 significantly decreased ACh levels both after systemic (by ～25%) and intrastriatal (by ～30-50%) administration. KYP-2047 decreased ACh levels only after intrastriatal administration by retrodialysis (by ～40-50%) when higher drug levels were reached, indicating that higher brain drug levels are needed to modulate ACh levels than to inhibit PREP. This result does not support the earlier hypothesis that the positive cognitive effects of PREP inhibitors in rodents would be mediated through the cholinergic system. In vitro specificity studies did not reveal any obvious off-targets that could explain the observed effect of KYP-2047 and JTP-4819 on ACh levels, instead confirming the concept that these compounds have a high selectivity towards PREP.     

Population estimates of Alfred mantas (<Emphasis Type="Italic">Manta alfredi</Emphasis>) in central Maldives atolls: North Male,Ari and Baa

The Alfred manta, Manta alfredi, is economically important in the Maldives due to the large number of tourists attracted to SCUBA dive and snorkel with them. It is important to understand the size of populations around main diving points and throughout the Maldives so that manta based tourism activities can be developed more successfully and the impact of tourism can be monitored. Using natural markings to identify individual manta rays, Petersen and Jolly-Seber probabilistic estimators were used to assess population size for main dive sites and the central atolls of North Male, Ari and Baa. Between 2000 and 2009, 1835 individual mantas were identified from 3373 sightings. There was a significant gender bias with a male: female ratio of 1:1.8. Only 24.7% of manta rays were re-sighted between 1 and 34 times with a maximum gap of 7 years and 11 months between sightings. Estimates for populations around main dive sites were 181–562. The estimated population of M. alfredi for North Male atoll is 537 (SE ± 53.2). Estimated atoll populations were extrapolated to obtain an estimate of Manta alfredi population for the entire Maldives of 9,677 individuals.     

Draft genome sequence of Novosphingobium nitrogenifigens Y88(T)

Novosphingobium nitrogenifigens was originally isolated from pulp and paper mill wastewater, a low-nitrogen, high-carbon environment. N. nitrogenifigens is the first known nitrogen-fixing, polyhydroxyalkanoate-accumulating sphingomonad, and we report the annotated draft genome sequence of the type strain Y88(T) here.     

Use of a LiESP/QA-21 vaccine (CaniLeish) stimulates an appropriate Th1-dominated cell-mediated immune response in dogs

Canine leishmaniasis is an important zoonotic disease of dogs. The clinical outcome of infection is variable, with the efficiency of the immune response being the key determining factor. There is now a general consensus that a predominant Th1 immune profile in an overall mixed Th1/Th2 response is associated with resistance in dogs, and the absence of a strong Th1 influence is associated with a progression to clinical disease. As a result, there has been a growing demand for vaccines that can induce a specific, strong Th1 response. In this study, we measured the impact of a primary course of a newly available LiESP/QA-21 vaccine on selected humoral and cellular markers of the canine immune response during the onset of immunity. All vaccinated dogs developed a humoral response characterised by IgG2 production. More importantly, vaccinated dogs developed significantly stronger cell-mediated immunity responses than did control dogs. Vaccination induced specific cellular reactivity to soluble Leishmania antigens, with a Leishmania-specific lymphoproliferation (p = 0.0072), characterised by an increased population of T lymphocytes producing IFN-γ (p = 0.0021) and a significant ability of macrophages to reduce intracellular parasite burdens in vitro after co-culture with autologous lymphocytes (p = 0.0014). These responses were correlated with induction of the NOS pathway and production of NO derivatives, which has been shown to be an important leishmanicidal mechanism. These results confirm that vaccination with LiESP/QA-21 induces an appropriate Th1-profile cell-mediated response within three weeks of completing the primary course, and that this response effectively reduces the parasite load in pre-infected macrophages in vitro.     

BTN3A2 expression in epithelial ovarian cancer is associated with higher tumor infiltrating T cells and a better prognosis

BTN3A2/BT3.2 butyrophilin mRNA expression by tumoral cells was previously identified as a prognostic factor in a small cohort of high grade serous epithelial ovarian cancer (HG-EOC). Here, we evaluated the prognostic value of BT3.2 at the protein level in specimen from 199 HG-EOC patients. As the only known role of butyrophilin proteins is in immune regulation, we evaluated the association between BT3.2 expression and intratumoral infiltration of immune cells by immunohistochemistry with specific antibodies against BT3.2, CD3, CD4, CD8, CD20, CD68 and CD206. Epithelial BT3.2 expression was significantly associated with longer overall survival and lower risk of disease progression (HR?=?0.651, p?=?0.006 and HR?=?0.642, p?=?0.002, respectively) and significantly associated with a higher density of infiltrating T cells, particularly CD4+ cells (0.272, p<0.001). We also observed a strong association between the relative density of CD206+ cells, as evaluated by the ratio of intratumoral CD206+/CD68+ expression, and risk of disease progression (HR?=?1.355 p?=?0.044, respectively). In conclusion, BT3.2 protein is a potential prognostic biomarker for the identification of HG-EOC patients with better outcome. In contrast, high CD206+/CD68+ expression is associated with high risk of disease progression. While the role of BT3.2 is still unknown, our result suggest that BT3.2 expression by epithelial cells may modulates the intratumoral infiltration of immune cells.     

Synthesis and evaluation of non-basic inhibitors of urokinase-type plasminogen activator (uPA)

Recent drug discovery programs targeting urokinase plasminogen activator (uPA) have resulted in nonpeptidic inhibitors consisting of amidine or guanidine functional groups attached to aromatic or heteroaromatic scaffolds. There is a general problem of poor oral bioavailability of these charged inhibitors. In this paper, we report the synthesis and evaluation of a series of naphthamide and naphthalene sulfonamides as uPA inhibitors containing non-basic groups as substitute for amidine or guanidine groups.