Tyrosine kinase signaling in action potential shortening and expression of HSP72 in late preconditioning

We investigated the role of tyrosine kinase (TK) signaling in the opening of the ATP-sensitive K(+) (K(ATP)) channel and 72-kDa heat shock protein (HSP72) expression during late preconditioning. Rabbits were subjected to surgical operation (sham) or were preconditioned (PC) with four cycles of 5 min of ischemia and 10 min of reperfusion. Twenty-four hours later, animals were subjected to 30 min of ischemia and 180 min of reperfusion. Genistein (1 mg/kg ip) was used to block the receptor TK. Six groups were studied: control, sham, genistein-sham, PC, genistein-PC, and vehicle-PC group (1% dimethyl sulfoxide). Genistein or vehicle was given 30 min before the surgical procedure. Genistein pretreatment decreased the expression of HSP72 in PC hearts and suppressed action potential duration shortening during ischemia in sham and PC groups. Infarct size (%risk area) was reduced in the PC (11.6 +/- 1.0%) and vehicle-PC (19.3 +/- 2.0%) compared with the control (40.0 +/- 3.8%) or sham (46.0 +/- 2.0%) groups (P < 0.05). Genistein pretreatment increased infarct size to 46.4 +/- 4.1% in the PC hearts. We conclude that TK signaling is involved in K(ATP) channel opening and HSP72 expression during late PC.     

Chemical components and their locations in the Verticillium fungicola cell wall

The chemical structure of cell walls and fractions of Verticillium fungicola, a pathogen of Agaricus bisporus, as well as their corresponding ultrastructures were studied. There are at least three chemically distinct types of carbohydrate polymers: one yielding mannose with lower amounts of galactose and glucose (glucogalactomannan), another one composed mainly of glucose (glucan), and a third one containing only N-acetylglucosamine (chitin). Attempts were made to locate these materials in situ by comparing electron micrographs of shadowed and sectioned cell walls, and also by indirect immunofluorescence. It was shown that none of these polymers constituted a completely physically distinct layer, but there seem to be different solubility properties in the outer, inner, and intermediate layers. It was also shown that fibrillar material (chitin) embedded in cementing glucan constituted the residual inner fraction of the original wall material. Indirect immunofluorescence showed the location of a significant amount of glucogalactomannan on the surface of the walls in which rodlet structures were visualized by electron microscopy.     

Selective Increase of α2A-Adrenoceptor Agonist Binding Sites in Brains of Depressed Suicide Victims

Abstract: The α_2A- and α_2C-adrenoceptor subtypes were evaluated in postmortem brains from suicides with depression (n = 22), suicides with other diagnoses (n = 12), and controls (n = 26). Membrane assays with the antagonist [³H]RX821002 (2-[³H]methoxyidazoxan) suggested the presence of α_2A-adrenoceptors in the frontal cortex and both α_2C-adrenoceptors and α_2A-adrenoceptors in the caudate. The proportions in caudate were similar in controls (α_2A, 86%; α_2C, 14%), depressed suicides (α_2A, 91%; α_2C, 9%), and suicides with other diagnoses (α_2A, 88%; α_2C, 12%). Autoradiography of [³H]RX821002 binding under α_2B/C-adrenoceptor-masking conditions confirmed the similar densities of α_2A-adrenoceptors in the cortex, hippocampus, and striatum from controls and suicides. In the frontal cortex of depressed suicides, competition of [³H]RX821002 binding by (?)-adrenaline revealed a greater proportion (61 ± 9%) of α_2A-adrenoceptors in the high-affinity conformation for agonists than in controls (39 ± 5%). Simultaneous analysis with the agonists [³H]clonidine and [³H]UK14304 and the antagonist [³H]RX821002 in the same depressed suicides confirmed the enhanced α_2A-adrenoceptor density when evaluated by agonist, but not by antagonist, radioligands. The results indicate that depression is associated with a selective increase in the high-affinity conformation of the brain α_2A-adrenoceptors.     

A survey of mycotic otitis externa of dogs in Lisbon

One hundred and thirteen dogs of different breeds and with different clinical forms of external otitis were mycologically and bacteriologically examined. Forty six of those dogs showed abnormal cerumen with a high yeasts contamination. These yeasts belong to four species: Malassezia pachydermatis (80.4%), Cryptococcus laurentii (13.1%), Candida parapsilosis (4.3%) and Trichosporon cutaneum (2.1%). All strains, excepting C. laurentii were highly lipolytic. Most of the clinical cases associated with those yeasts were chronic, with hyperkeratosis and lichenification, and most of them were relapsed otitis (91.3%). The most affected dogs were a pendulous ears breeding (65.7%) and males (86.8%). Some dogs had other cutaneous disorders (seborrhoeic dermatitis, pemphigus). In vitro tests, using seven different antifungal drugs were systematically performed. All strains revealed to be 5-fluorocytosine-resistant and 32% of them were also resistant to nystatin. One M. pachydermatis isolated was resistant to all of the tested antifungal drugs.     

Carotid Intima-Media Thickness at Age 30, Birth Weight,Accelerated Growth during Infancy and Breastfeeding: A Birth Cohort Study in Southern Brazil

Objective

To examine the relationship between carotid intima-media thickness (IMT) at age 30 and birth characteristics, growth during infancy, and breastfeeding duration, among subjects who have been prospectively followed since birth.

Methods and Results

In 1982, all births in the city of Pelotas, southern Brazil, were identified and those children (n = 5,914) whose families lived in the urban area of the city have been followed and evaluated at several time points. The cohort participants were evaluated in 2012–13, and IMT was measured at the posterior wall of the right and left common carotid arteries in longitudinal planes using ultrasound imaging. We obtained valid IMT measurements for 3,188 individuals. Weight-for-age z-score (WAZ) at age 2 years, weight-for-height z-score (WHZ) at age 4, height-for-age z-score (HAZ) at 4 years, WAZ at age 4 and relative conditional weight at 4 years were positively associated with IMT, even after controlling for confounding variables. The beta-coefficient associated with ≥1 s.d. WAZ at age 2 (compared to those with a <–1 s.d.) was 3.62 μm (95% CI 0.86 to 6.38). The beta-coefficient associated with ≥1 s.d. WHZ at 4 (in relation to <–1 s.d) was 3.83 μm (95% CI 0.24 to 7.42). For HAZ at 4, the beta-coefficient for ≥1 s.d. in relation to <–1 s.d. was 4.19 μm (95% CI 1.14 to 7.25). For WAZ at 4, the beta-coefficient associated with ≥1 s.d. in relation to <–1 s.d. was 4.28 μm (95% CI 1.59 to 6.97). The beta-coefficient associated with conditional weight gain at age 2–4 was 1.26 μm (95% CI 0.49 to 2.02).

Conclusion

IMT at age 30 was positively associated with WAZ at age 2 years, WHZ at age 4, HAZ at age 4, WAZ at age 4 and conditional weight gain at age 4 years.     

Cross-Sectional and Prospective Associations between Physical Activity and C-Reactive Protein in Males

BackgroundThere is conflicting evidence about the association between physical activity and inflammatory markers. Few prospective studies are available, particularly from low and middle-income countries. This study was aimed at assessing the cross-sectional and prospective associations between physical activity and C-reactive protein (CRP) levels in males belonging to the 1982 Pelotas (Brazil) Birth Cohort Study.MethodsThe sample comprised 2,213 males followed up at the ages of 18 and 23 years. We performed high sensitivity CRP assays; we used a cut-off of 3 mg/L in categorical analyses. We measured physical activity by self-report at ages 18 and 23 years. Body mass index and waist circumference were studies as possible mediators.ResultsCRP levels above the 3mg/L cut-off were found in 13.3% (95%CI: 11.7; 14.8) of the individuals. We found no evidence for an association between physical activity (leisure-time or all-domains) and either continuous (geometrical mean) or categorical CRP. We confirmed these null findings in (a) prospective and cross-sectional analyses; (b) trajectories analyses.ConclusionsThere was no association between CRP levels and physical activity levels in early adulthood in a large birth cohort. Little variability in CRP at this early age is the likely explanation for these null findings.     

Biomass,sugar, and bioethanol potential of sweet corn

Sweet corn is a widely distributed crop that generates agricultural waste without significant commercial value. In this study, we show that sweet corn varieties produce large amounts of residual biomass (10 t ha^?1) with high content of soluble sugars (25% of dry matter) in a short growing season (3 months). The potential ethanol production from structural and soluble sugars extracted from sweet corn stover reached up to 4400 l ha^?1 in the most productive hybrids, 33% of which (1500 l ha^?1) were obtained by direct fermentation of free sugars. We found wide genetic variation for biomass yield and soluble sugars content suggesting that those traits can be included as complementary traits in sweet corn breeding programs. Dual‐purpose sweet corn hybrids can have an added value for the farmers contributing to energy generation without affecting food supply or the environment.     

A meta-analysis on pyrogenic organic matter induced priming effect

Pyrogenic organic matter (PyOM) is considered an important soil carbon (C) sink. However, there are evidences that its addition to soil may induce a priming effect (PE) thus influencing its C abatement potential. The direction, the size and the mechanisms responsible for PyOM induced PE are far from being understood. We collected approximately 650 data points from 18 studies to analyse the characteristics of the PE induced by PyOM. The database was divided between the PE induced on the native soil organic matter and on fresh organic matter. Most of the studies were short-term incubation therefore the projections of findings on the long term may be critical. Our findings indicate that over 1 year PyOM induces an average positive PE of 0.3 mg C g⁻¹ soil on native soil organic matter and a PE of approximately the same size but opposite direction on fresh organic matter. We studied the correlation of PE with several properties of soil, of the added PyOM, and time after PyOM addition. We found that PyOM primes positively the native soil organic matter in the first 20 days while negative PE appears in a later stage. Negative PE was correlated with the soil C content. PyOM characterized by a low C content induced a higher positive PE on native soil organic carbon. No correlation was found between the factors record in our database and the PE induced on the fresh organic matter. We reviewed the mechanisms proposed in literature to explain PE and discussed them based on findings from our meta-analysis. We believe that the presence of a labile fraction in PyOM may trigger the activity of soil microorganisms on the short term and therefore induce a positive PE, while on the long term PyOM may induce a negative PE by promoting physical protection mechanisms.     

Human Metapneumovirus Is Capable of Entering Cells by Fusion with Endosomal Membranes

Human metapneumovirus (HMPV), a member of the Paramyxoviridae family, is a leading cause of lower respiratory illness. Although receptor binding is thought to initiate fusion at the plasma membrane for paramyxoviruses, the entry mechanism for HMPV is largely uncharacterized. Here we sought to determine whether HMPV initiates fusion at the plasma membrane or following internalization. To study the HMPV entry process in human bronchial epithelial (BEAS-2B) cells, we used fluorescence microscopy, an R18-dequenching fusion assay, and developed a quantitative, fluorescence microscopy assay to follow virus binding, internalization, membrane fusion, and visualize the cellular site of HMPV fusion. We found that HMPV particles are internalized into human bronchial epithelial cells before fusing with endosomes. Using chemical inhibitors and RNA interference, we determined that HMPV particles are internalized via clathrin-mediated endocytosis in a dynamin-dependent manner. HMPV fusion and productive infection are promoted by RGD-binding integrin engagement, internalization, actin polymerization, and dynamin. Further, HMPV fusion is pH-independent, although infection with rare strains is modestly inhibited by RNA interference or chemical inhibition of endosomal acidification. Thus, HMPV can enter via endocytosis, but the viral fusion machinery is not triggered by low pH. Together, our results indicate that HMPV is capable of entering host cells by multiple pathways, including membrane fusion from endosomal compartments.