Evaluation of Cardiovascular Risk Factors in the Wistar Audiogenic Rat (WAR) Strain

Introduction

Risk factors for life-threatening cardiovascular events were evaluated in an experimental model of epilepsy, the Wistar Audiogenic Rat (WAR) strain.

Methods

We used long-term ECG recordings in conscious, one year old, WAR and Wistar control counterparts to evaluate spontaneous arrhythmias and heart rate variability, a tool to assess autonomic cardiac control. Ventricular function was also evaluated using the pressure-volume conductance system in anesthetized rats.

Results

Basal RR interval (RRi) was similar between WAR and Wistar rats (188±5 vs 199±6 ms). RRi variability strongly suggests that WAR present an autonomic imbalance with sympathetic overactivity, which is an isolated risk factor for cardiovascular events. Anesthetized WAR showed lower arterial pressure (92±3 vs 115±5 mmHg) and exhibited indices of systolic dysfunction, such as higher ventricle end-diastolic pressure (9.2±0.6 vs 5.6±1 mmHg) and volume (137±9 vs 68±9 μL) as well as lower rate of increase in ventricular pressure (5266±602 vs 7320±538 mmHg.s-1). Indices of diastolic cardiac function, such as lower rate of decrease in ventricular pressure (-5014±780 vs -7766±998 mmHg.s^-1) and a higher slope of the linear relationship between end-diastolic pressure and volume (0.078±0.011 vs 0.036±0.011 mmHg.μL), were also found in WAR as compared to Wistar control rats. Moreover, Wistar rats had 3 to 6 ventricular ectopic beats, whereas WAR showed 15 to 30 ectopic beats out of the 20,000 beats analyzed in each rat.

Conclusions

The autonomic imbalance observed previously at younger age is also present in aged WAR and, additionally, a cardiac dysfunction was also observed in the rats. These findings make this experimental model of epilepsy a valuable tool to study risk factors for cardiovascular events in epilepsy.     

Restriction cleavage maps of the DNAs of Streptococcus pneumoniae bacteriophages containing protein covalently bound to their 5'' ends

Summary Several pneumococcal bacteriophages showing a morphology similar to that previously described for Cp-1 (Ronda et al. 1981) have been isolated and purified from throat samples taken from healthy children. Three of these phages (Cp-5, Cp-7 and Cp-9) have been studied in detail and compared to Cp-1. The four phages differed in several respects, e.g. size, structural polypeptides, restriction enzyme cleavage patterns, etc. The DNA of Cp-5, Cp-7 and Cp-9 showed protease-sensitive transfecting activity. This, together with the results obtained by electrophoretic analyses as well as by isotopic labelling of these DNAs with [-³²P] ATP and polynucleotide kinase indicated that all these new phages have a protein covalently linked to the 5 ends of their DNAs as in the case of Cp-1 (García et al. 1983). Restriction enzyme cleavage maps of Cp-1, Cp-5, Cp-7 and Cp-9 have been constructed.     

Anatomical and morphological characterization of mycorrhizas of five strains of Tuber borchii Vittad

 Tilia platyphyllos Scop. plantlets were inoculated in vitro with five Tuber borchii Vittad. strains (1BO, 17BO, 43BO, 71BO and 10RA) to test their intraspecific variability. The ability of the strains to form mycorrhizas varied, with the mean degree of ectomycorrhizal infection ranging from 50.6% (for 1BO) to 82.1% (for 10RA). The anatomical/morphological characteristics of the resulting mycorrhizas were determined. Although the morphological features of the mycorrhizas and the characteristics of the cystidia were similar for all strains tested, differences were found in the anatomical features of the mantle. The form of the mantle cells was examined in the surface and inner layers (6 and 12 μm deep, respectively) by both conventional and confocal microscopy. These cells were polygonal in 1BO, and 71BO, epidermoid in 43BO and intermediate in 17BO and 10RA. The structure of the mantle also varied and thus provided little information with which to identify T. borchii mycorrhizas. Accepted: 7 July 2000     

Suppressed Retinal Degeneration in Aged Wild Type and APPswe/PS1ΔE9 Mice by Bone Marrow Transplantation

Alzheimer''s disease (AD) is an age-related condition characterized by accumulation of neurotoxic amyloid β peptides (Aβ) in brain and retina. Because bone marrow transplantation (BMT) results in decreased cerebral Aβ in experimental AD, we hypothesized that BMT would mitigate retinal neurotoxicity through decreased retinal Aβ. To test this, we performed BMT in APPswe/PS1ΔE9 double transgenic mice using green fluorescent protein expressing wild type (wt) mice as marrow donors. We first examined retinas from control, non-transplanted, aged AD mice and found a two-fold increase in microglia compared with wt mice, prominent inner retinal Aβ and paired helical filament-tau, and decreased retinal ganglion cell layer neurons. BMT resulted in near complete replacement of host retinal microglia with BMT-derived cells and normalized total AD retinal microglia to non-transplanted wt levels. Aβ and paired helical filament-tau were reduced (61.0% and 44.1% respectively) in BMT-recipient AD mice, which had 20.8% more retinal ganglion cell layer neurons than non-transplanted AD controls. Interestingly, aged wt BMT recipients also had significantly more neurons (25.4%) compared with non-transplanted aged wt controls. Quantitation of retinal ganglion cell layer neurons in young mice confirmed age-related retinal degeneration was mitigated by BMT. We found increased MHC class II expression in BMT-derived microglia and decreased oxidative damage in retinal ganglion cell layer neurons. Thus, BMT is neuroprotective in age-related as well as AD-related retinal degeneration, and may be a result of alterations in innate immune function and oxidative stress in BMT recipient mice.     

Genome analysis and clinical implications of the bacterial communities in early biofilm formation on dental implants restored with titanium or zirconia abutments

This cross-sectional study aimed to identify and quantify up to 42 target species colonizing the early biofilm of dental implants restored with titanium or zirconia abutments. A total of 720 samples from 20 healthy individuals were investigated. Biofilm samples were collected from the peri-implant sulci, inner parts of implants, abutment surfaces and prosthetic crowns over a functioning period of 30 days. Checkerboard DNA–DNA hybridization was used for microbial detection and quantitation. Clinical characteristics (probing depth, bleeding on probing, clinical attachment level and marginal bone loss) were also investigated during the monitoring period. Genome counts were low at the implant loading time point for both the abutment materials, and increased over time. Both the titanium and the zirconia groups presented similar microbial counts and diversity over time, and the microbiota was very similar to that colonizing the remaining teeth. Clinical findings were consistent with a healthy condition with no significant difference regarding marginal bone loss between the two materials.     

Developmental outcomes in children exposed to Zika virus in utero from a Brazilian urban slum cohort study

BackgroundThe prevalence of developmental alterations associated with in-utero Zika virus (ZIKV) exposure in children is not well understood. Furthermore, estimation of the Population Attributable Fraction (PAF) of developmental alterations attributed to ZIKV has not been performed due to lack of population-based cohorts with data on symptomatic and asymptomatic ZIKV exposures and an appropriate control group. The aim of this study was to characterize neurodevelopmental outcomes of children at 11 to 32 months of age with intrauterine ZIKV exposure and estimate the PAF of alterations secondary to ZIKV exposure.Methodology/Principal findingsWe performed a cohort of biannual community-based prospective serosurveys in a slum community in Salvador, Brazil. We recruited women participating in our cohort, with a documented pregnancy from January 2015 to December 2016 and children born to those mothers. Children were classified as ZIKV exposed in utero (born from women with ZIKV seroconversion during pregnancy) or unexposed (born from women without ZIKV seroconversion or that seroconverted before/after pregnancy) by using an IgG monoclonal antibody blockade-of-binding (BoB). We interviewed mothers and performed anthropometric, audiometric, ophthalmological, neurologic, and neurodevelopmental evaluations of their children at 11 to 32 months of age. Among the 655 women participating in the cohort, 66 (10%) were pregnant during the study period. 46 (70%) of them completed follow-up, of whom ZIKV seroconversion occurred before, during, and after pregnancy in 25 (54%), 13 (28%), and 1 (2%), respectively. The rest of women, 7 (21.2%), did not present ZIKV seroconversion. At 11 to 32 months of life, the 13 ZIKV-exposed children had increased risk of mild cognitive delay (RR 5.1; 95%CI 1.1–24.4) compared with the 33 children unexposed, with a PAF of 53.5%. Exposed children also had increased risk of altered auditory behavior (RR 6.0; 95%CI 1.3–26.9), with a PAF of 59.5%.ConclusionsA significant proportion of children exposed in utero to ZIKV developed mild cognitive delay and auditory behavioral abnormalities even in the absence of gross birth defects such as microcephaly and other neurodevelopmental domains. Furthermore, our findings suggest that over half of these abnormalities could be attributed to intrauterine ZIKV exposure.     

So alike yet so different. Differential expression of the long non-coding RNAs NORAD and HCG11 in breast cancer subtypes

Breast cancer (BC) is a heterogeneous disease, and it is the leading cause of death among women. NORAD and HCG11 are highly similar lncRNAs that present binding sites for PUMILIO proteins. PUMILIO acts on hundreds of mRNA targets, contributing to the modulation of gene expression. We analyzed the expression levels of NORAD and HCG11 in the BC subtypes luminal A (LA) and basal-like (BL), and the regulatory networks associated with these lncRNAs. In the analysis of TCGA cohort (n=329) and Brazilian BC samples (n=44), NORAD was up-regulated in LA while HCG11 was up-regulated in BL subtype. An increased expression of NORAD is associated with reduced disease-free survival in basal-like patients (p = 0.002), which suggests that its prognostic value could be different in specific subtypes. The biological pathways observed for the HCG11 network are linked to the epithelial-to-mesenchymal transition; while NORAD associated pathways appear to be related to luminal epithelial cell transformation. NORAD and HCG11 regulons respectively present 36% and 21.5% of PUMILIO targets, which suggests that these lncRNAs act as a decoy for PUMILIO. These lncRNAs seem to work as players in the differentiation process that drives breast cells to acquire distinct phenotypes related to a specific BC subtype.     

Circumtropical distribution of the epiphytic dinoflagellate Coolia malayensis (Dinophyceae): Morphology and molecular phylogeny from Puerto Rico and Brazil

The dinoflagellate genus Coolia, which contains potentially toxic species, is an important component of epiphytic assemblages in marine ecosystems. The morphology of C. malayensis has been illustrated from strains isolated in Asia and Oceania. In this study, strains of C. malayensis isolated from the Caribbean Sea in Puerto Rico, and for the first time from the South Atlantic Ocean in Brazil, were investigated by light, epifluorescence and scanning electron microscopies. No significant morphological differences between these new strains and other geographically distant strains of C. malayensis were observed. In the LSU rDNA phylogeny, the C. malayensis sequences from Brazil and Puerto Rico branched within the clade of strains from Oceania and Asia. The recently described species C. santacroce branched as a sister group of C. monotis, and C. palmyrensis was basal to the combined group of C. monotis/C. malayensis/C. santacroce. A tentative undescribed species from Florida and New Zealand branched as a sister group of C. malayensis. Our results confirm that C. malayensis showed a cosmopolitan distribution in tropical to subtropical waters, while the type species C. monotis remains endemic for the Mediterranean Sea and the temperate North Atlantic.     

Simulation of integrated first and second generation bioethanol production from sugarcane: comparison between different biomass pretreatment methods

Sugarcane bagasse is used as a fuel in conventional bioethanol production, providing heat and power for the plant; therefore, the amount of surplus bagasse available for use as raw material for second generation bioethanol production is related to the energy consumption of the bioethanol production process. Pentoses and lignin, byproducts of the second generation bioethanol production process, may be used as fuels, increasing the amount of surplus bagasse. In this work, simulations of the integrated bioethanol production process from sugarcane, surplus bagasse and trash were carried out. Selected pre-treatment methods followed, or not, by a delignification step were evaluated. The amount of lignocellulosic materials available for hydrolysis in each configuration was calculated assuming that 50% of sugarcane trash is recovered from the field. An economic risk analysis was carried out; the best results for the integrated first and second generation ethanol production process were obtained for steam explosion pretreatment, high solids loading for hydrolysis and 24–48 h hydrolysis. The second generation ethanol production process must be improved (e.g., decreasing required investment, improving yields and developing pentose fermentation to ethanol) in order for the integrated process to be more economically competitive.