Effects of chronic manganese exposure on working memory in non-human primates

Human exposure to manganese (Mn) has been associated with a variety of cognitive deficits including learning and memory deficits. However, results from epidemiological studies have been inconsistent in describing the nature of such cognitive deficits. The present study was conducted to evaluate the effects of chronic Mn exposure on memory functioning in non-human primates and to correlate behavioral outcome with brain Mn levels in an attempt to explain outcome variability seen in prior studies. Cynomolgus macaque monkeys were trained to perform memory-related tasks (spatial working memory, non-spatial working memory, reference memory) and exposed to manganese sulfate (15-20 mg/kg/week) over an exposure period lasting 227.5+/-17.3 days. Blood manganese levels were in the upper range of levels reported for human environmental, medical or occupational exposures. By the end of the manganese exposure period, animals developed mild deficits in spatial working memory, more significant deficits in non-spatial working memory and no deficits in reference memory. Linear regression analyses showed that for most brain regions sampled, there was a significant inverse relationship between working memory task performance and brain Mn concentration. These results suggest that chronic exposure to levels of manganese achieved in this study may have detrimental effects on working memory and that Mn levels achieved in several brain regions are inversely related to working memory performance.

Ongoing controversies in the pharmacological management of cancer pain

Pain management remains a problem in advanced cancer. Despite the ready availability of effective analgesia and good evidence to support the prescription of medications, concerns continue over the safety of this practice. The aim of the present paper was to review often-raised questions when considering the use of opioids, especially in cancer pain, to ascertain the levels of evidence that already exist to support opioid-prescribing practice and to identify areas where further research is needed.

Increased potency and longevity of gene silencing using validated Dicer substrates

Chemically synthesized small interfering RNAs (siRNAs) are tools used for silencing the expression of a single gene. They are mainly employed in basic research applications, but may also have great potential in therapeutic applications. Longer double-stranded RNAs, such as Dicer-substrate 27mers, trigger gene silencing through the intrinsic RNAi pathway. The design of these Dicer-substrate 27mers has been optimized so they can be oriented by Dicer to consistently select the antisense (guide) strand after cleavage to shorter siRNAs, leading to predictable mRNA cleavage. In this paper we describe evidence that these Dicer-substrate 27mers produce more potent and sustained gene silencing for four genes when compared with synthetic 21mers that have the same guide-strand sequence. Furthermore, improved silencing by these 27mers is often more pronounced at lower concentrations.

Exploring functional genomics for drug target and therapeutics discovery in Plasmodia

Functional genomics approaches are indispensable tools in the drug discovery arena and have recently attained increased attention in antibacterial drug discovery research. However, the application of functional genomics to post-genomics research of Plasmodia is still in comparatively early stages. Nonetheless, with this genus having the most species sequenced of any eukaryotic organism so far, the Plasmodia could provide unique opportunities for the study of intracellular eukaryotic pathogens. This review presents the status quo of functional genomics of the malaria parasite including descriptions of the transcriptome, proteome and interactome. We provide examples for the in silico mining of the X-ome data sets and illustrate how X-omic data from drug challenged parasites might be used in elucidating amongst others, the mode-of-action of inhibitory compounds, validate potential targets and discover novel targets/therapeutics.

Biopsychosocial problems identified by women with breast cancer

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Background: It is frequently assumed that women with breast cancer have higher levels of distress and psychosocial problems than women with other malignancies. We compared the biopsychosocial needs of breast cancer patients with women with non-breast malignancies. Methods: A biopsychosocial screening tool was developed from clinical practice, focus groups, and the administration of questionnaires to over 3,000 patients. The refined 36-item self-administered questionnaire was completed by all new patients evaluated in the Moores Cancer Center. The severity of each problem was scored from 1 (not a problem) to 5 (the worst problem I could have). Problems scored as 3 or above were identified to be clinically significant. The screening results from women with breast cancer were compared with those of women with non-breast malignancies. Results: Between December 2005 and December 2006, 2063 patients completed screening questionnaires. Complete information, including staging, is available on 299 women, 155 of whom were diagnosed with breast cancer and 144 with non-breast malignancies. The two groups were comparable with respect to age, ethnicity, and the number of significant problems reported. The 5 most common problems identified to be significant by breast cancer patients included: fatigue, sleeping, being dependent on others, feeling depressed, and pain. The non-breast cancer women identified a greater number of significant problems overall with the 5 most significant being: fatigue, sleep, controlling my fear and worry about the future, being dependent on others, and pain. Getting medications and recent weight loss were more commonly identified in the non-breast cancer patients (p<0.05). Conclusions: Our data suggest that breast cancer patients identify similar biopsychosocial needs as women with other primary malignancies.

No significant financial relationships to disclose.

Lymphotoxin alpha and tumour necrosis factor are not required for control of parasite growth, but differentially regulate cytokine production during Plasmodium chabaudi chabaudi AS infection

Tumour necrosis factor (TNF) plays important roles in the pathogenesis of severe malaria, as well as in the generation of immune responses against malaria parasites. However, far less is known about the role of the closely related TNF family member lymphotoxin alpha (LTalpha) during malaria. We have used mice deficient in either TNF or LTalpha, as well as chimeric mice generated using donor bone marrow from these animals, to study the roles of these cytokines following Plasmodium chabaudi chabaudi AS infection. TNF and LTalpha were not required for the resolution of P. chabaudi chabaudi AS blood-stage infection. However, LTalpha, but not TNF, was necessary for early IFNgamma production and the regulation of IFNgamma production later in infection. A similar delay to that found for IFNgamma production was also observed for TNF production in LTalpha-deficient mice, compared with control mice. These results identify divergent roles for TNF and LTalpha in the regulation of host immune responses during P. chabaudi chabaudi AS infection.

246 IN VITRO PRODUCTION OF SPRINGBOK (ANTIDORCAS MARSUPIALIS) EMBRYOS

The objective of this experiment was to develop in vitro embryo production (IVP) technologies in springbok (Antidorcas marsupialis), a southern African antelope. Springbok, a fairly common species on game farms in parts of South Africa, may be used as a model species for gamete rescue and IVP techniques to be applied to the conservation of other threatened antelope species. Springbok belong to the family bovidae, subfamily antilopinae, tribe antilopini, which comprises about twenty species in genera Gazella, Antilope, Procapra, Antidorcas, Litocranius, and Ammodorcas. In this tribe alone, there are 4 species or subspecies that are critically endangered, 3 that are endangered, and 10 that are considered vulnerable, demonstrating the need for antelope conservation efforts. In addition, our studies contributed to the South African biological resource bank, so that banked springbok semen and embryos might be used in the future for managed genetic contribution to isolated captive or wild populations via assisted reproductive technologies. Oocytes were recovered (3 replicates) from ovaries obtained at supervised culls for management purposes in South Africa, and cultured in defined Gmat or undefined TCM-199 with FCS maturation medium for 28-30 h (Brad et al. 2004 Reprod. Fertil. Dev. 16, 223). Oocytes were fertilized with frozen-thawed springbok epididymal spermatozoa in modified SOF fertilization medium with caffeine (Herrick et al. 2004 Biol. Reprod. 71, 948–958). Eighteen hours after insemination, a randomly selected subset of the zygotes were fixed to determine fertilization success. The remaining zygotes were cultured in G1/G2 media. On Day 7 of culture, embryos were analyzed for development to the morula or blastocyst stage. A total of 259 selected oocytes were collected from 50 females (5.2 selected oocytes/female on average). There was no difference in the percentage of oocytes normally fertilized (2 pronuclei, PN) between oocytes matured in Gmat (n= 43; 12%) and those matured in TCM-199 (n= 42; 10%). There were significantly (P &lt; 0.05) more oocytes penetrated (e2 PN) when matured in TCM (50%) compared to Gmat (23%). There were no differences in embryonic cleavage or morula/blastocyst development (of total oocytes inseminated) between treatments (Gmat,n= 89, 54%, 9.0%; TCM-199, n= 85, 68%, 9.4%, respectively). In both treatments, the average blastocyst grade was 2.125 using the standard bovine grading system (Curtis, Cattle Embryo Transfer Procedure, 1991). In conclusion, in vitro oocyte maturation, fertilization, and embryo culture to the blastocyst stage is possible in springbok. Importantly, blastocysts can be produced in vitro under semi-defined conditions, demonstrating that oocyte maturation without serum does support developmental competence. This is important for the potential international movement of IVP embryos to be used for genetic management in the conservation of antelope species.

Measurement of the asymmetry in the decay Omega+-->LamdaKappa+-->rhopi+Kappa+

The asymmetry in the rho angular distribution in the sequential decay Omega+-->LamdaKappa+-->rhopi+Kappa+. has been measured to be alphaOmegaalphaLamda=[+1.16+/-0.18(stat)+/-0.17(syst)]x10(-2) using 1.89x10(6) unpolarized Omega+ decays recorded by the HyperCP (E871) experiment at Fermilab. Using the known value of alphaLamda, and assuming that alphaLamda=-alphaLamda, alphaOmega=[-1.81+/-0.28(stat)+/-0.26(syst)]x10(-2). A comparison between this measurement of alphaOmegaalphaLamda and recent measurements of alphaOmegaalphaLamda made by HyperCP shows no evidence of a violation of CP symmetry.

Methane and nitrous oxide emissions from Canadian animal agriculture: A review

Considerable evidence of climate change associated with emissions of greenhouse gases (GHG) has resulted in international efforts to reduce GHG emissions. The agriculture sector contributes about 8% of GHG emissions in Canada mostly through methane (CH4) and nitrous oxide (N2O). The objective of this paper was to compile an integrative review of CH4 and N2O emissions from livestock by taking a whole cycle approach from enteric fermentation to manure treatment and storage, and field application of manure. Basic microbial processes that result in CH4 production in the rumen and hindgut of animals were reviewed. An overview of CH4 and N2O production processes in manure, and controlling factors are presented. Most of the studies conducted in relation to enteric fermentation were in dairy and beef cattle. To date, research has focussed on GHG emissions from the stored manures of dairy, beef cattle and swine; therefore, we focus our review on these. Several methods used to measure GHG emissions from livestock and stored manure were reviewed. A comparison of methods showed that there were agreements between most of the techniques but some systematic differences were also observed. Additional studies with comprehensive comparisons of methodologies are needed in order to allow for comparison of results obtained from studies using contrasting methodologies. The need to standardize measurement methods and reporting to facilitate comparison of results and data integration was identified. Prediction equations are often used to calculate GHG emissions. Various types of mathematical approaches, such as statistical models, mechanistic models and estimates calculated from emission factors, and studies that compare various types of models are discussed herein. A lack of process-based models describing GHG emissions from manure during storage was identified. A brief description of mitigation strategies focussing on recent studies is given. Reduction in CH4 emissions from ruminants through the addition of fats in diets and the use of more starch was achieved and a transient beneficial effect of ionophores was reported. Grazing management and genetic selection also hold promise. Studies focussed on manure treatment options that thave been suggested to reduce gas fluxes from manure storage, composting, anaerobic digestion (AD), diet manipulation, covers and solid-liquid separation, were reviewed. While some of these options have been shown to decrease GHG emissions from stored manure, different studies have obtained conflicting results, and additional research is needed to identify the most promising options. GHG emissions from pasture and croplands after manure application have been the subject of several experimental and modelling studies, but few of these have linked field emissions to diet manipulation or manure treatments. Further work focussing on the entire cycle of GHG formation from feed formulation, animal metabolism, excreta treatment and storage, to field application of manure needs to be conducted. Key words: Greenhouse gases, enteric methane, nitrous oxide, manure management

Biochemical characterization of Drosophila gamma-glutamyl carboxylase and its role in fly development

To investigate structure-function relationships in gamma-glutamyl carboxylases, the enzyme from Drosophila melanogaster was characterized. Four cysteine residues were shown to be important determinants for enzymatic activity. Native Drosophila substrates have not yet been identified, but propeptides of human prothrombin and factor IX are recognized by the Drosophila enzyme. The presence of the propeptide region increased apparent affinity by approximately 200-fold, and mutation of a hydrophobic residue of factor IX propeptide (F-16A) decreased carboxylation by 90%, as in the human enzyme. Substrate recognition appears to be highly conserved between the human and Drosophila gamma-glutamyl carboxylases. Inactivation of Drosophila gamma-glutamyl carboxylase by non-sense mutations or insertional mutagenesis by P-element insertion have no apparent effects on growth and fertility under laboratory conditions.

Direct dark matter search using large-mass superheated droplet detectors in the PICASSO experiment

The PICASSO experiment investigates the presence and nature of dark matter in the Universe. The experiment is based on the detection of acoustic signals generated in explosive phase transitions induced by dark matter particles. This technique is an alternative more traditional detection technique like scintillation and ionisation, which are largely employed for dark matter search. One of the main advantages of this technique, besides its sensitivity to very low nuclear recoil energies (few keV), is its excellent background suppression features. A pilot experiment consisting of six superheated droplet detectors (40 g of active mass) is presently taking data at the Sudbury Neutrino Observatory (SNO) at a depth of 2000 m. We discuss the operation, calibration and data acquisition of the experiment and also the ongoing work to increase the sensitivity and the active mass of the detectors.

Growth rates of the blowfly, Lucilia sericata, on different body tissues

Estimates of post-mortem interval based on forensic analysis of the age of blowfly larvae on a corpse, are generated from standardised larval development curves. These are derived from studies of the growth of larvae reared, usually, on liver and at a range of temperatures. However, it is possible that the species or organ on which the larvae feed, might significantly alter the rate of growth. The present study therefore compared the development of the blowfly Lucilia sericata (Meigen) (Diptera: Calliphoridae) fed on lung, liver and heart, from both cows and pigs. Half of the tissue samples used were liquidised while half were not, to assess whether structural differences in the food source were important. Larvae grew significantly faster and gave rise to larger adults when reared on pig compared to cow tissue and when reared on lung and heart compared to liver. Larvae completed feeding and wandered from the food source 31h earlier and grew 2mm longer when reared on lung compared to liver. Tissue structure had no or little effect on development. For the forensic entomologist, these results highlight the importance of recording the position of larvae removed from a body and the care that should be used when extrapolating development rates from standard curves based on larvae fed on only a single medium, particularly where that is liver.

Simulation of special bubble detectors for PICASSO

The PICASSO project is a cold dark matter (CDM) search experiment relying on the superheated droplet technique. The detectors use superheated freon liquid droplets (active material) dispersed and trapped in a polymerised gel. This detection technique is based on the phase transition of superheated droplets at about room temperature and ambient pressure. The phase transition is induced by nuclear recoils when an atomic nucleus in the droplets interacts with incoming subatomic particles. This includes CDM particles candidate as the neutralino (a yet-to-discover particle predicted in extensions of the standard model of particle physics). Simulations performed to understand the detector response to neutrons and alpha particles are presented along with corresponding data obtained at the Montreal Laboratory.

[Medical hypnosis in cases of herpes labialis improves resistance for recurrence. A pilot study]

The present study examined the effectiveness of a hypnotherapeutic treatment program for patients suffering from recurrent orofacial herpes infections. Twenty-one patients were randomly allocated to either an experimental group (n=10) or a control condition (n=11). During five weekly individual therapy sessions the participants received symptom-oriented treatment. In addition, they learnt how to improve their stress coping skills and their management of aversive emotions. The final assessment took place 6 months after treatment. Besides documentation of the frequency and intensity of symptoms, questionnaires were administered to assess stress coping mechanisms (SVF), skin disease-related subjective strain (MHF) and perceptions of control (KKG). A significant reduction of disease intensity could be confirmed. Individual scales of the SVF and MHF also revealed significant results. For an effective treatment of severe herpes infections a mere focus on physical changes appears to be insufficient. A common reflection of a person's sensuality and expectations of closeness and distance seem to influence treatment success remarkably.

Search for the lepton-number-violating decay Xi(-)-->pmu(-)mu(-)

A sensitive search for the lepton-number-violating decay Xi(-)-->pmu(-)mu(-) has been performed using a sample of approximately 10(9) Xi(-) hyperons produced in 800 GeV/c p-Cu collisions. We obtain B(Xi(-)-->pmu(-)mu(-))<4.0x10(-8) at 90% confidence, improving on the best previous limit by 4 orders of magnitude.

Mechanisms of integration of cells and extracellular matrices by integrins

While it is self-evident that all extracellular molecules are an integral part of a multicellular organism, it is paradoxical that they are often considered to be dissociated from cells. The reality is that a continuum of dynamic, bi-directional interactions links the intracellular environment through cell-surface receptors to multimolecular extracellular assemblies. These interactions not only control the behaviour of individual cells, but also determine tissue architecture. Adhesion receptor function is partly determined by an ability to tether the contractile cytoskeleton to the plasma membrane, but there is also evidence that integrin receptors modulate signalling events that are essential for cellular differentiation. A major challenge is now to integrate work at the atomic, molecular and cellular levels, and obtain holistic insights into the mechanisms controlling cell adhesion. In the present study, we review current knowledge of the molecular mechanisms employed by cells to integrate with the extracellular matrix. Two main topics are covered: the adaptation of integrin structure for bi-directional signalling and the integration of integrin signalling with other receptors.

Search for DeltaS = 2 nonleptonic hyperon decays

A sensitive search for the rare decays Omega(-)--> Lambdapi(-) and Xi(0)--> ppi(-) has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |DeltaS| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(Omega(-)-->Lambdapi(-)) < 2.9 x 10(-6) and B(Xi(0)--> ppi(-)) < 8.2 x 10(-6), both at 90% confidence level.

Evidence for the decay sigma+ --> pmu+ mu-

We report the first evidence for the decay Sigma(+)-->pmu(+)mu(-) from data taken by the HyperCP (E871) experiment at Fermilab. Based on three observed events, the branching ratio is B(Sigma(+)-->pmu(+)mu(-))=[8.6(+6.6)(-5.4)(stat)+/-5.5(syst)]x10(-8). The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, Sigma(+)-->pP(0),P0-->mu(+)mu(-) with a P0 mass of 214.3+/-0.5 MeV/c(2) and branching ratio B(Sigma(+)-->pP(0),P0-->mu(+)mu(-))=[3.1(+2.4)(-1.9)(stat)+/-1.5(syst)]x10(-8).

Search for CP violation in charged-Xi and Lambda hyperon decays

We have compared the p and p angular distributions in 117 x 10(6) Xi- -->Lambdapi- -->ppi-pi- and 41 x 10(6) Xi+ -->Lambda pi+ -->p pi+pi+ decays using a subset of the data from the HyperCP experiment (E871) at Fermilab. We find no evidence of CP violation, with the direct-CP-violating parameter AXiLambda identical with (alphaXialphaLambda-alpha Xialpha Lambda)/(alphaXialphaLambda+alphaXialphaLambda)=[0.0+/-5.1(stat)+/-4.4(syst)] x 10(-4).