Copper sulphate treatment induces <i>Heterozostera</i> seed germination and improves seedling growth rates

Evidence for seed germination and/or seedling recruitment in wild populations of the Southern Hemisphere seagrass H. nigricaulis are lacking. Additionally, seeds of H. nigricaulis, have proven extremely difficult to store and germinate in laboratories, even when using techniques for germination proven successful in other Zosteraceae. Prior studies reveal Zosteraceae seed and seedling failure may be correlated with oomycete infections. Copper sulphate treatments can reduce oomycete and other seagrass infections in laboratory tests. Here, we tested whether copper sulphate seed treatments promote germination and seedling growth in H. nigricaulis. We found treatment with 2.0 ppm copper sulphate solution induced significant seed germination and led to 3 times more photosynthesizing H. nigricaulis seedlings after 3 months. Thus, in addition to reducing disease, copper sulphate appears to be a novel cue for H. nigricaulis germination and improves seedling development and success in H. nigricaulis. This discovery will improve our opportunities to overcome biogeochemical germination cues and bottlenecks for Zosteraceae and improve seed-based seagrass restoration strategies where copper sulphate treatment is available to pre-treat and cue germination and promote seedling development and growth

Cholesterol in condensed and fluid phosphatidylcholine monolayers studied by epifluorescence microscopy

Epifluorescence microscopy was used to investigate the effect of cholesterol on monolayers of dipalmitoylphosphatidylcholine (DPPC) and 1 -palmitoyl-2-oleoyl phosphatidylcholine (POPC) at 21 +/- 2 degrees C using 1 mol% 1-palmitoyl-2-[12-[(7-nitro-2–1, 3-benzoxadizole-4-yl)amino]dodecanoyl]phosphatidylcholine (NBD-PC) as a fluorophore. Up to 30 mol% cholesterol in DPPC monolayers decreased the amounts of probe-excluded liquid-condensed (LC) phase at all surface pressures (pi), but did not effect the monolayers of POPC, which remained in the liquid-expanded (LE) phase at all pi. At low pi (2–5 mN/m), 10 mol% or more cholesterol in DPPC induced a lateral phase separation into dark probe-excluded and light probe-rich regions. In POPC monolayers, phase separation was observed at low pi when > or =40 mol% or more cholesterol was present. The lateral phase separation observed with increased cholesterol concentrations in these lipid monolayers may be a result of the segregation of cholesterol-rich domains in ordered fluid phases that preferentially exclude the fluorescent probe. With increasing pi, monolayers could be transformed from a heterogeneous dark and light appearance into a homogeneous fluorescent phase, in a manner that was dependent on pi and cholesterol content. The packing density of the acyl chains may be a determinant in the interaction of cholesterol with phosphatidylcholine (PC), because the transformations in monolayer surface texture were observed in phospholipid (PL)/sterol mixtures having similar molecular areas. At high pi (41 mN/m), elongated crystal-like structures were observed in monolayers containing 80–100 mol% cholesterol, and these structures grew in size when the monolayers were compressed after collapse. This observation could be associated with the segregation and crystallization of cholesterol after monolayer collapse

Evaluation of seals and lubricants used on the Long Duration Exposure Facility

This report described results from testing and analysis of seals and lubricants subsequent to the 69-month low-earth-orbit (LEO) exposure on the Long Duration Exposure Facility (LDEF). Results show that if the materials were shielded from exposure to LDEF's external environment, the 69-month exposure to LEO resulted in minimal changes to material properties. However, if the materials were exposed to LDEF's exterior environments (atomic oxygen, solar radiation, meteoroids, and/or space debris), a variety of events occurred, ranging from no material change, to changes in properties, to significant erosion of the material

Elevated Epidermal Ornithine Decarboxylase Activity Suppresses Contact Hypersensitivity

Previous reports have shown that elevated polyamine biosynthesis is sufficient to promote skin tumorigenesis in susceptible mouse strains. We hypothesized that increased activity of epidermal ornithine decarboxylase (ODC), a key regulatory enzyme in polyamine biosynthesis, may suppress the cutaneous immune response in addition to stimulating proliferation. Using an ODCER transgenic mouse model in which ODC is targeted to the epidermis, we examined the effect of ODC overexpression in keratinocytes on a classic contact hypersensitivity (CHS) response. Compared with normal littermate mice, ODCER transgenic mice showed reduced ear swelling, reduced neutrophil infiltration, and decreased migration of fluorescein isothiocyanate-loaded dendritic cells (DCs) to draining lymph nodes following hapten elicitation of CHS. In addition, elevated epidermal ODC activity suppressed the levels of cytokines keratinocyte-derived chemokine, monocyte chemoattractant protein-1, interleukin-6 (IL-6), and IL-10. Adoptive transfer of lymphocytes from sensitized ODCER transgenic or normal littermate mice to naive ODCER transgenic or wild-type mice indicated that elevated epidermal ODC activity suppresses both the sensitization and elicitation phases of CHS. The specific ODC inhibitor, α-difluoromethylornithine, abrogated all suppressive effects of ODC in CHS reactions. Collectively, these data suggest that the immunosuppression promoted by increased epidermal ODC is mediated by a reduction in cytokine levels, which suppresses DC migration and reduces immune cell infiltration to the site of hapten application

Identification of Novel Tumor Antigens With Patient-Derived Immune-Selected Antibodies

The identification of tumor antigens capable of eliciting an immune response in vivo may be an effective method to identify therapeutic cancer targets. We have developed a method to identify such antigens using frozen tumor-draining lymph node samples from breast cancer patients. Immune responses in tumor-draining lymph nodes were identified by immunostaining lymph node sections for B-cell markers (CD20&CD23) and Ki67 which revealed cell proliferation in germinal center zones. Antigen-dependent somatic hypermutation (SH) and clonal expansion (CE) were present in heavy chain variable (VH) domain cDNA clones obtained from these germinal centers, but not from Ki67 negative germinal centers. Recombinant VH single-domain antibodies were used to screen tumor proteins and affinity select potential tumor antigens. Neuroplastin (NPTN) was identified as a candidate breast tumor antigen using proteomic identification of affinity selected tumor proteins with a recombinant VH single chain antibody. NPTN was found to be highly expressed in approximately 20% of invasive breast carcinomas and 50% of breast carcinomas with distal metastasis using a breast cancer tissue array. Additionally, NPTN over-expression in a breast cancer cell line resulted in a significant increase in tumor growth and angiogenesis in vivo which was related to increased VEGF production in the transfected cells. These results validate NPTN as a tumor-associated antigen which could promote breast tumor growth and metastasis if aberrantly expressed. These studies also demonstrate that humoral immune responses in tumor-draining lymph nodes can provide antibody reagents useful in identifying tumor antigens with applications for biomarker screening, diagnostics and therapeutic interventions

Can a clinical placement influence stigma? An analysis of measures of social distance

Background The way people who experience mental illness are perceived by health care professionals, which often includes stigmatising attitudes, can have a significant impact on treatment outcomes and on their quality of life. Objective To determine whether stigma towards people with mental illness varied for undergraduate nursing students who attended a non-traditional clinical placement called Recovery Camp compared to students who attended a \u27typical\u27 mental health clinical placement. Design Quasi-experimental. Participants Seventy-nine third-year nursing students were surveyed; n = 40 attended Recovery Camp (intervention), n = 39 (comparison group) attended a \u27typical\u27 mental health clinical placement. Methods All students completed the Social Distance Scale (SDS) pre- and post-placement and at three-month follow-up. Data analysis consisted of a one-way repeated measures analysis of variance (ANOVA) exploring parameter estimates between group scores across three time points. Two secondary repeated measures ANOVAs were performed to demonstrate the differences in SDS scores for each group across time. Pairwise comparisons demonstrated the differences between time intervals. Results A statistically significant difference in ratings of stigma between the intervention group and the comparison group existed. Parameter estimates revealed that stigma ratings for the intervention group were significantly reduced post-placement and remained consistently low at three-month follow-up. There was no significant difference in ratings of stigma for the comparison group over time. Conclusions Students who attended Recovery Camp reported significant decreases in stigma towards people with a mental illness over time, compared to the typical placement group. Findings suggest that a therapeutic recreation based clinical placement was more successful in reducing stigma regarding mental illness in undergraduate nursing students compared to those who attended typical mental health clinical placements

Examining co-patterns of depression and alcohol misuse in emerging adults following university graduation

Depression and alcohol use disorders are highly comorbid. Typically, alcohol use peaks in emerging adulthood (e.g., during university), and many people also develop depression at this time. Self-medication theory predicts that depressed emerging adults drink to reduce negative emotions. While research shows that depression predicts alcohol use and related problems in undergraduates, far less is known about the continuity of this association after university. Most emerging adults “mature out” of heavy drinking; however, some do not and go on to develop an alcohol use disorder. Depressed emerging adults may continue to drink heavily to cope with the stressful (e.g., remaining unemployed) transition out of university. Accordingly, using parallel process latent class growth modelling, we aimed to distinguish high- from low-risk groups of individuals based on joint patterns of depression and alcohol misuse following university graduation. Participants (N = 123) completed self-reports at three-month intervals for the year post-graduation. Results supported four classes: class 1: low stable depression and low decreasing alcohol misuse (n = 52), class 2: moderate stable depression and moderate stable alcohol misuse (n = 35), class 3: high stable depression and low stable alcohol misuse (n = 29), and class 4: high stable depression and high stable alcohol misuse (n = 8). Our findings show that the co-development of depression and alcohol misuse after university is not uniform. Most emerging adults in our sample continued to struggle with significant depressive symptoms after university, though only two classes continued to drink at moderate (class 2) and high (class 4) risk levels

Impulsivity moderates the effect of social anxiety on in-lab alcohol craving

Social anxiety (SA) is thought to relate to alcohol misuse. However, current evidence is inconsistent – especially in young adulthood. Recent non-experimental data show that trait impulsivity moderates the effect of SA on alcohol misuse. Specifically, this work suggests that concurrently elevated impulsivity may draw attention to the immediate, anxiolytic effects of drinking – thus promoting alcohol misuse among those high in SA. Otherwise, without elevated impulsivity, a socially anxious person may not drink due to focusing on alcohol's possible negative outcomes (e.g., embarrassing behaviours). The next step in this research is to examine if impulsivity impacts in-the-moment subjective craving among socially anxious individuals. This was the goal of the present experiment. After baseline measures, undergraduate participants (N = 110) completed the Trier Social Stress Test followed by an alcohol (versus neutral) cue exposure. Subjective craving ratings were collected at both baseline and post-cue exposure. Moderation analyses revealed that socially anxious individuals endorsed strong cravings following an alcohol (but not a neutral) cue exposure, but only if they also had elevated impulsivity. In-lab craving was positively correlated with retrospective reports of alcohol misuse. Our findings demonstrate that impulsivity contributes to SA-related risk for alcohol misuse