Fate of Pathogenic Bacteria in Microcosms Mimicking Human Body Sites

During the infectious process, pathogens may reach anatomical sites where they are exposed to substances interfering with their growth. These substances can include molecules produced by the host, and his resident microbial population, as well as exogenous antibacterial drugs. Suboptimal concentrations of inhibitory molecules and stress conditions found in vivo (high or low temperatures, lack of oxygen, extreme pH) might induce in bacteria the activation of survival mechanisms blocking their division capability but allowing them to stay alive. These “dormant” bacteria can be reactivated in particular circumstances and would be able to express their virulence traits. In this study, it was evaluated the effect of some environmental conditions, such as optimal and suboptimal temperatures, direct light and antibiotic sub-inhibitory concentrations doses of antibiotic, on the human pathogens Escherichia coli and Enterococcus faecalis when incubated in fluids accumulated in the body of patients with different pathologies. It is shown that inoculation in a number of accumulated body fluids and the presence of gentamicin, reliable conditions encountered during pathological states, induce stress-responding strategies enabling bacteria to persist in microcosms mimicking the human body. Significant differences were detected in Gram-negative and Gram-positive species with E. faecalis surviving, as starved or viable but non-culturable forms, in any microcosm and condition tested and E. coli activating a viable but non-culturable state only in some clinical samples. The persistence of bacteria under these conditions, being non-culturable, might explain some recurrent infections without isolation of the causative agent after application of the standard microbiological methods.     

Effects of road salt deicers on sediment biogeochemistry

Road salt deicers, especially NaCl and CaCl₂, are increasingly applied to paved areas throughout the world. The goal of this study is to investigate the influence of high concentrations of these salts on wetland biogeochemistry. Sediment cores were collected in fall and spring from a freshwater wetland fringing an urban kettle lake (Asylum Lake, Kalamazoo, MI, USA), and incubated for 100 days in deionized water (control) or with treatments of 1 or 5 g/L CaCl₂·2H₂O or 5 g/L NaCl to simulate addition of road salt deciers. At monthly intervals, cores were sliced into three depths (0–5, 5–10, 10–15 cm) and pore waters extracted for analysis of pH, total alkalinity and dissolved Mn(II), Fe(II), PO ₄ ^?3 , NH₃, H₂S, SO₄ ^?2, Na, K, Mg, and Ca. Changes in solid phase geochemistry were assessed by measuring the percent organic matter and the distribution of Fe and Mn among four operationally defined sediment fractions (exchangeable, carbonate, reducible, oxidizable) in the control and treatment cores. Addition of NaCl, and especially CaCl₂, stimulated significant growth of microbial mats at the core sediment–water interface and led to decreased pH and increased concentrations of Mn(II), Fe(II) and exchangeable cations (Ca, Mg, K, Na) in the sediment pore waters. This study demonstrates that the influx of road salt deciers is likely to have a significant impact on biogeochemical cycling in wetland sediments.     

Detection of Leishmania infantum in animals and their ectoparasites by conventional PCR and real time PCR

Visceral leishmaniosis (VL) is a parasitic disease caused by Leishmania infantum, which is primarily transmitted by phlebotomine sandflies. However, there has been much speculation on the role of other arthropods in the transmission of VL. Thus, the aim of this study was to assess the presence of L. infantum in cats, dogs and their ectoparasites in a VL-endemic area in northeastern Brazil. DNA was extracted from blood samples and ectoparasites, tested by conventional PCR (cPCR) and quantitative real time PCR (qPCR) targeting the L. infantum kinetoplast DNA. A total of 280 blood samples (from five cats and 275 dogs) and 117 ectoparasites from dogs were collected. Animals were apparently healthy and not previously tested by serological or molecular diagnostic methods. Overall, 213 (76.1 %) animals and 51 (43.6 %) ectoparasites were positive to L. infantum, with mean parasite loads of 795.2, 31.9 and 9.1 fg in dogs, cats and ectoparasites, respectively. Concerning the positivity between dogs and their ectoparasites, 32 (15.3 %) positive dogs were parasitized by positive ectoparasites. The overall concordance between the PCR protocols used was 59.2 %, with qPCR being more efficient than cPCR; 34.1 % of all positive samples were exclusively positive by qPCR. The high number of positive animals and ectoparasites also indicates that they could serve as sentinels or indicators of the circulation of L. infantum in risk areas.     

From Dust to Ashes: The Challenges of Difference

By attending to ways in which middle-class wives in Yogyakarta, Java, describe negotiating sentiments among family members (including children, maids and husbands), this article argues that domestic relations in middle-class homes in Java have been importantly inflected by state rhetoric on gender propriety and market ideas of work. As a result, both middle-class women and maids have come to conceive of emotion work as part of an array of domestic obligations central to social reproduction.     

A class of pyrrole derivatives endowed with analgesic/anti-inflammatory activity

We report the synthesis and bio-pharmacological evaluation of a class of pyrrole derivatives featuring a small appendage fragment (carbaldehyde, oxime, nitrile) on the central core. Compound 1c proved to be extremely effective in vivo, showing an interesting anti-nociceptic profile that is comparable to reference compounds already marketed, hence representing a great stimulus for a further improvement of this class of molecules.     

Bioactive compounds from Stuhlmannia moavi from the Madagascar dry forest

Bioassay-directed fractionation of the leaf and root extracts of the antiproliferative Madagascar plant Stuhlmannia moavi afforded 6-acetyl-5,8-dihydroxy-2-methoxy-7-methyl-1,4-naphthoquinone (stuhlmoavin, 1) as the most active compound, with an IC₅₀ value of 8.1 μM against the A2780 human ovarian cancer cell line, as well as the known homoisoflavonoid bonducellin (2) and the stilbenoids 3,4,5′-trihydroxy-3′-methoxy-trans-stilbene (3), piceatannol (4), resveratrol (5), rhapontigenin (6), and isorhapontigenin (7). The structure elucidation of all compounds was based on NMR and mass spectroscopic data, and the structure of 1 was confirmed by a single crystal X-ray analysis. Compounds 2?5 showed weak A2780 activities, with IC₅₀ values of 10.6, 54.0, 41.0, and 74.0 μM, respectively. Compounds 1?3 also showed weak antimalarial activity against Plasmodium falciparum with IC₅₀ values of 23, 26, and 27 μM, respectively.     

Extra-virgin olive oil diet and mild physical activity prevent cartilage degeneration in an osteoarthritis model: an in vivo and in vitro study on lubricin expression

Mediterranean diet includes a relatively high fat consumption mostly from monounsaturated fatty acids mainly provided by olive oil, the principal source of culinary and dressing fat. The beneficial effects of olive oil have been widely studied and could be due to its phytochemicals, which have been shown to possess anti-inflammatory properties. Lubricin is a chondroprotective glycoprotein and it serves as a critical boundary lubricant between opposing cartilage surfaces. A joint injury causes an initial flare of cytokines, which decreases lubricin expression and predisposes to cartilage degeneration such as osteoarthritis. The aim of this study was to evaluate the role of extra-virgin olive oil diet and physical activity on inflammation and expression of lubricin in articular cartilage of rats after injury. In this study we used histomorphometric, histological, immunocytochemical, immunohistochemical, western blot and biochemical analysis for lubricin and interleukin-1 evaluations in the cartilage and in the synovial fluid. We report the beneficial effect of physical activity (treadmill training) and extra-virgin olive oil supplementation, on the articular cartilage. The effects of anterior cruciate ligament transection decrease drastically the expression of lubricin and increase the expression of interleukin-1 in rats, while after physical activity and extra-virgin olive oil supplemented diet, the values return to a normal level compared to the control group. With our results we can confirm the importance of the physical activity in conjunction with extra-virgin olive oil diet in medical therapy to prevent osteoarthritis disease in order to preserve the articular cartilage and then the entire joint.     

Activation of phosphatidylinositol-3 kinase,AMP-activated kinase and Akt substrate-160 kDa by trans-10, cis-12 conjugated linoleic acid mediates skeletal muscle glucose uptake

Conjugated linoleic acid (CLA), a dietary lipid, has been proposed as an antidiabetic agent. However, studies specifically addressing the molecular dynamics of CLA on skeletal muscle glucose transport and differences between the key isomers are limited. We demonstrate that acute exposure of L6 myotubes to cis-9, trans-11 (c9,t11) and trans-10, cis-12 (t10,c12) CLA isomers mimics insulin action by stimulating glucose uptake and glucose transporter-4 (GLUT4) trafficking. Both c9,t10-CLA and t10,c12-CLA stimulate the phosphorylation of phosphatidylinositol 3-kinase (PI3-kinase) p85 subunit and Akt substrate-160 kDa (AS160), while showing isomer-specific effects on AMP-activated protein kinase (AMPK). CLA isomers showed synergistic effects with the AMPK activator, 5-aminoimidazole-4-carboxamide-1-β-d-ribonucleoside (AICAR). Blocking PI3-kinase and AMPK prevented the stimulatory effects of t10,c12-CLA on AS160 phosphorylation and glucose uptake, indicating that this isomer acts via a PI3-kinase and AMPK-dependent mechanism, whereas the mechanism of c9,t11-CLA remains unclear. Intriguingly, CLA isomers sensitized insulin-Akt-responsive glucose uptake and prevented high insulin-induced Akt desensitisation. Together, these results establish that CLA exhibits isomer-specific effects on GLUT4 trafficking and the increase in glucose uptake induced by CLA treatment of L6 myotubes occurs via pathways that are distinctive from those utilised by insulin.     

Actin acting at the Golgi

The organization, assembly and remodeling of the actin cytoskeleton provide force and tracks for a variety of (endo)membrane-associated events such as membrane trafficking. This review illustrates in different cellular models how actin and many of its numerous binding and regulatory proteins (actin and co-workers) participate in the structural organization of the Golgi apparatus and in trafficking-associated processes such as sorting, biogenesis and motion of Golgi-derived transport carriers.