Activity of AMP-Regulated Protein Kinase and AMP-Deaminase in the Heart of Mice Fed High-Fat Diet

AMP-regulated protein kinase (AMPK) is involved in numerous regulatory processes and its role in control of cardiac energy metabolism is particularly important. This activity could be affected by AMP-deaminase (AMPD) since substrate of AMPD is AMPK activator. Hearts of male mouse, fed for six weeks with normal or high-fat diet, were fractionated to enrich AMPK activity. Purified fraction was incubated with AMARA peptide for up to 5 minutes and then conversion of AMARA to pAMARA was determined by liquid chromatography—mass spectrometry (LC/MS) using mass detector. Activity of AMPK in heart was 0.038 ± 0.012 pmol/min/mg protein for mice fed high-fat diet and that was not different to control (0.032 ± 0.01 pmol/min/mg protein). We observed change in AMPD activity. It was 5.39 ± 1.5 nmol/mg tissue/min in heart of mice fed high-fat diet while in heart of mice fed low-fat diet it was 2.29 ± 0.32 nmol/mg tissue/min. Data we present indicate that while total AMPK activity is not changed decrease in AMPD activity may affect AMPK signaling in diabetic heart.     

Invasive American Mink: Linking Pathogen Risk Between Domestic and Endangered Carnivores

Infectious diseases, in particular canine distemper virus (CDV), are an important threat to the viability of wild carnivore populations. CDV is thought to be transmitted by direct contact between individuals; therefore, the study of species interactions plays a pivotal role in understanding CDV transmission dynamics. However, CDV often appears to move between populations that are ecologically isolated, possibly through bridge hosts that interact with both species. This study investigated how an introduced species could alter multihost interactions and act as a bridge host in a novel carnivore assemblage of domestic dogs (Canis familiaris), invasive American mink (Neovison vison), and threatened river otters (Lontra provocax) in southern Chile. We found that rural dogs interact with mink near farms whereas in riparian habitats, minks and river otters shared the same latrines with both species visiting sites frequently within time intervals well within CDV environmental persistence. No interactions were observed between dogs and otters at either location. Both dog and mink populations were serologically positive for CDV, making the pathogen transfer risk to otters a conservation concern. Altogether, introduced mink in this ecosystem have the potential to act as bridge hosts between domestic dogs and endangered carnivores.     

Immunocompetence and high metabolic rates enhance overwinter survival in the root vole,Microtus oeconomus

Despite its presumed significance, the association between immune defence, energy expenditures and overwinter survival is rarely studied. We analysed individual variation in immunocompetence quantified as neutrophil-to-lymphocyte ratio (N/L), total white blood cells (WBC) and natural antibody levels, along with resting (RMR) and peak metabolic rates (PMR) and mortality during three consecutive winter seasons in a natural population of the root vole, Microtus oeconomus. In early winter, WBC count was negatively correlated with RMR, whereas N/L ratio was negatively correlated with swim-elicited PMR. We suggest that while the first correlation reflected the trade-off between energy allocation in immunocompetence and other metabolically demanding processes, the latter correlation stemmed from stress-induced immunosuppression elicited by the necessity to cope with swimming in frequently flooded habitat. In addition, the analysis carried out during the first year of study characterized by a high population density and prevalence of infestation with a blood parasite—Babesia spp., showed that its intensity was inversely correlated with the N/L ratio. In summary, our results suggest that elevated N/L ratio increases the winter survival of free-ranging rodents by increasing their ability to cope with parasitic infections.     

Diabetes Increases the Expression of Hypothalamic Neuropeptides in a Spontaneous Model of Type I Diabetes, the Nonobese Diabetic (NOD) Mouse

1. Synthesis of oxytocin (OT) and arginine-vasopressin(AVP) is increased in induced models of Type I diabetes, such as thestreptozotocin model. However, these parameters have not yet been evaluated inspontaneous models, such as the nonobese diabetic mouse (NOD). Therefore, we studied in the magnocellular cells of the paraventricular nucleus (PVN)of nondiabetic and diabetic 16-week-old female NOD mice and control C57Bl/6mice, the immunocytochemistry of OT and AVP peptides and their mRNA expression, using nonisotopic in situ hybridization (ISH).2. In nondiabetic and diabetic NOD female mice, the number of OT- and AVP-immunoreactive cells were similar to those of the controls, whereas immunoreaction intensity was significantly higher for both peptides in diabetic NOD as compared with nondiabetic NOD and control C57Bl/6 mice.3. ISH analysis showed that the number of OT mRNA-containing cells was in the same range in the three groups, whereas higher number of AVP mRNA expressing cells was found in diabetic NOD mice. However, the intensity of hybridization signal was also higher for both OT and AVP mRNA in the diabetic group as compared with nondiabetic NOD and control mice.4. Blood chemistry demonstrated that haematrocrit, total plasma proteins, urea, sodium, and potassium were within normal limits in diabetic mice. Thus, NODmice were neither hypernatremic nor dehydrated.5. We suggest that upregulation of OT and AVP reflects a high-stress condition in the NOD mice. Diabetes may affect neuropeptide-producing cells of the PVN, with the increased AVP and OT playing a deleterious role on the outcome of the disease.     

Endothelium Trans Differentiated from Wharton's Jelly Mesenchymal Cells Promote Tissue Regeneration: Potential Role of Soluble Pro-Angiogenic Factors

Background

Mesenchymal stem cells have a high capacity for trans-differentiation toward many adult cell types, including endothelial cells. Feto-placental tissue, such as Wharton''s jelly is a potential source of mesenchymal stem cells with low immunogenic capacity; make them an excellent source of progenitor cells with a potential use for tissue repair. We evaluated whether administration of endothelial cells derived from mesenchymal stem cells isolated from Wharton''s jelly (hWMSCs) can accelerate tissue repair in vivo.

Methods

Mesenchymal stem cells were isolated from human Wharton''s jelly by digestion with collagenase type I. Endothelial trans-differentiation was induced for 14 (hWMSC-End14d) and 30 (hWMSC-End30d) days. Cell phenotyping was performed using mesenchymal (CD90, CD73, CD105) and endothelial (Tie-2, KDR, eNOS, ICAM-1) markers. Endothelial trans-differentiation was demonstrated by the expression of endothelial markers and their ability to synthesize nitric oxide (NO).

Results

hWMSCs can be differentiated into adipocytes, osteocytes, chondrocytes and endothelial cells. Moreover, these cells show high expression of CD73, CD90 and CD105 but low expression of endothelial markers prior to differentiation. hWMSCs-End express high levels of endothelial markers at 14 and 30 days of culture, and also they can synthesize NO. Injection of hWMSC-End30d in a mouse model of skin injury significantly accelerated wound healing compared with animals injected with undifferentiated hWMSC or injected with vehicle alone. These effects were also observed in animals that received conditioned media from hWMSC-End30d cultures.

Conclusion

These results demonstrate that mesenchymal stem cells isolated from Wharton''s jelly can be cultured in vitro and trans-differentiated into endothelial cells. Differentiated hWMSC-End may promote neovascularization and tissue repair in vivo through the secretion of soluble pro-angiogenic factors.     

Stimulators of Mineralization Limit the Invasive Phenotype of Human Osteosarcoma Cells by a Mechanism Involving Impaired Invadopodia Formation

Background

Osteosarcoma (OS) is a highly aggressive bone cancer affecting children and young adults. Growing evidence connects the invasive potential of OS cells with their ability to form invadopodia (structures specialized in extracellular matrix proteolysis).

Results

In this study, we tested the hypothesis that commonly used in vitro stimulators of mineralization limit the invadopodia formation in OS cells. Here we examined the invasive potential of human osteoblast-like cells (Saos-2) and osteolytic-like (143B) OS cells treated with the stimulators of mineralization (ascorbic acid and B-glycerophosphate) and observed a significant difference in response of the tested cells to the treatment. In contrast to 143B cells, osteoblast-like cells developed a mineralization phenotype that was accompanied by a decreased proliferation rate, prolongation of the cell cycle progression and apoptosis. On the other hand, stimulators of mineralization limited osteolytic-like OS cell invasiveness into collagen matrix. We are the first to evidence the ability of 143B cells to degrade extracellular matrix to be driven by invadopodia. Herein, we show that this ability of osteolytic-like cells in vitro is limited by stimulators of mineralization.

Conclusions

Our study demonstrates that mineralization competency determines the invasive potential of cancer cells. A better understanding of the molecular mechanisms by which stimulators of mineralization regulate and execute invadopodia formation would reveal novel clinical targets for treating osteosarcoma.     

Do Interventions Designed to Support Shared Decision-Making Reduce Health Inequalities? A Systematic Review and Meta-Analysis

Background

Increasing patient engagement in healthcare has become a health policy priority. However, there has been concern that promoting supported shared decision-making could increase health inequalities.

Objective

To evaluate the impact of SDM interventions on disadvantaged groups and health inequalities.

Design

Systematic review and meta-analysis of randomised controlled trials and observational studies.

Data Sources

CINAHL, the Cochrane Register of Controlled Trials, the Cochrane Database of Systematic Reviews, EMBASE, HMIC, MEDLINE, the NHS Economic Evaluation Database, Open SIGLE, PsycINFO and Web of Knowledge were searched from inception until June 2012.

Study Eligibility Criteria

We included all studies, without language restriction, that met the following two criteria: (1) assess the effect of shared decision-making interventions on disadvantaged groups and/or health inequalities, (2) include at least 50% of people from disadvantaged groups, except if a separate analysis was conducted for this group.

Results

We included 19 studies and pooled 10 in a meta-analysis. The meta-analyses showed a moderate positive effect of shared decision-making interventions on disadvantaged patients. The narrative synthesis suggested that, overall, SDM interventions increased knowledge, informed choice, participation in decision-making, decision self-efficacy, preference for collaborative decision making and reduced decisional conflict among disadvantaged patients. Further, 7 out of 19 studies compared the intervention''s effect between high and low literacy groups. Overall, SDM interventions seemed to benefit disadvantaged groups (e.g. lower literacy) more than those with higher literacy, education and socioeconomic status. Interventions that were tailored to disadvantaged groups'' needs appeared most effective.

Conclusion

Results indicate that shared decision-making interventions significantly improve outcomes for disadvantaged patients. According to the narrative synthesis, SDM interventions may be more beneficial to disadvantaged groups than higher literacy/socioeconomic status patients. However, given the small sample sizes and variety in the intervention types, study design and quality, those findings should be interpreted with caution.     

Intranasal Delivery of Influenza rNP Adjuvanted with c-di-AMP Induces Strong Humoral and Cellular Immune Responses and Provides Protection against Virus Challenge

There is a critical need for new influenza vaccines able to protect against constantly emerging divergent virus strains. This will be sustained by the induction of vigorous cellular responses and humoral immunity capable of acting at the portal of entry of this pathogen. In this study we evaluate the protective efficacy of intranasal vaccination with recombinant influenza nucleoprotein (rNP) co-administrated with bis-(3′,5′)-cyclic dimeric adenosine monophosphate (c-di-AMP) as adjuvant. Immunization of BALB/c mice with two doses of the formulation stimulates high titers of NP-specific IgG in serum and secretory IgA at mucosal sites. This formulation also promotes a strong Th1 response characterized by high secretion of INF-γ and IL-2. The immune response elicited promotes efficient protection against virus challenge. These results suggest that c-di-AMP is a potent mucosal adjuvant which may significantly contribute towards the development of innovative mucosal vaccines against influenza.     

Oxidation of Ferrous Iron and Elemental Sulfur by Thiobacillus ferrooxidans

The oxidation of ferrous iron and elemental sulfur by Thiobacillus ferrooxidans that was absorbed and unabsorbed onto the surface of sulfur prills was studied. Unadsorbed sulfur-grown cells oxidized ferrous iron at a rate that was 3 to 7 times slower than that of ferrous iron-grown cells, but sulfur-grown cells were able to reach the oxidation rate of the ferrous iron-adapted cells after only 1.5 generations in a medium containing ferrous iron. Bacteria that were adsorbed to sulfur prills oxidized ferrous iron at a rate similar to that of unadsorbed sulfur-grown bacteria. They also showed the enhancement of ferrous iron oxidation activity in the presence of ferrous iron, even though sulfur continued to be available to the bacteria in this case. An increase in the level of rusticyanin together with the enhancement of the ferrous iron oxidation rate were observed in both sulfur-adsorbed and unadsorbed cells. On the other hand, sulfur oxidation by the adsorbed bacteria was not affected by the presence of ferrous iron in the medium. When bacteria that were adsorbed to sulfur prills were grown at a higher pH (ca. 2.5) in the presence of ferrous iron, they rapidly lost both ferrous iron and sulfur oxidation capacities and became inactive, apparently because of the deposition of a jarosite-like precipitate onto the surface to which they were attached.