Vascular and apoptotic changes in the placode of myelomeningocele mice during the final stages of in utero development

JOAQUIM L. REIS, M.D., PH.D.,1,2 JORGE CORREIA-PINTO, M.D., PH.D.,3,4 MARIANA P. MONTEIRO, M.D., PH.D.,1 MADALENA COSTA, B.SC.,1 AND GROVER M. HUTCHINS, M.D.5 1Department of Anatomy, Abel Salazar Institute for the Biomedical Sciences and Unit for Multidisciplinary Biomedical Research, University of Porto; 2Department of Neurosurgery, Santo António General Hospital; 4Department of Pediatric Surgery, São João Hospital, Porto; 3Life and Health Sciences Research Institute, School of Health Sciences, University of Minho, Braga, Portugal; and 5Department of Pathology, Johns Hopkins School of Medicine, Baltimore, Maryland Object. Myelomeningocele (MMC) is a primary neurulation defect that is associated with devastating neurological disabilities in affected newborns. To better characterize the in utero neurodegenerative process of MMC, the authors investigated the changes in vascular organization, apoptosis, and the presence of inflammatory cells during gestation by using a mutant mouse model of MMC. Methods. The curly tail/loop tail (ct/lp) mutant mouse model of MMC was chosen to obtain fetuses at different stages of gestation. Mouse fetuses harboring MMC were harvested by caesarean section at embryonic Days 14.5, 16.5, and 18.5 (complete mouse gestation at 19 days, 6 mice/group); littermate fetuses with the same gestational age but without an MMC were used as controls. Samples of the MMC placode or normal spinal cord were stained for immunocytochemical labeling with caveolin antibody (endothelium marker) and activated caspase-3 antibody (apoptosis marker). Samples were morphometrically analyzed with a computer-assisted image analyzer. Results. The MMC mice presented with an increase in vascular density from embryonic Days 16.5–18.5 and an enhanced number of apoptotic cells at embryonic Day 18.5, compared with controls. There were scarce signals of an inflammatory reaction in the MMC placode, as a few infiltrating neutrophils were seen only at embryonic Day 18.5. Conclusions. Fetal placodes in MMC mice showed evidence of increased vascular density since embryonic Day 16.5 and increased apoptosis at embryonic Day 18.5. These new data support the view that in utero changes of the MMC placode, occurring during the last stages of gestation, contribute to the neuropathological manifestations in fullterm newborns with MMC. (DOI: 10.3171/PED/2008/2/8/150

Vortex behavior near a spin vacancy in 2D XY-magnets

The dynamical behavior of anisotropic two dimensional Heisenberg models is still a matter of controversy. The existence of a central peak at all temperatures and a rich structure of magnon peaks are not yet understood. It seems that the central peaks are related, in some way, to structures like vortices. In order to contribute to the discussion of the dynamical behavior of the model we use Monte Carlo and spin dynamics simulations as well analytical calculations to study the behavior of vortices in the presence of nonmagnetic impurities. Our simulations show that vortices are attracted and trapped by the impurities. Using this result we show that if we suppose that vortices are not very much disturbed by the presence of the impurities, then they work as an attractive potential to the vortices explaining the observed behavior in our simulations.Comment: 4 pages, 6 figure

Enhancement of antimicrobial activity of antibiotics and antifungals by the use of natural products from Pityrogramma calomelanos (L.) link

The ethanol extract and methanol fraction of Pityrogramma calomelanos (L.) link were evaluated for antibacterial, antifungal and modulatory activities against strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, C. krusei and C. tropicalis. The antimicrobial activity of the natural products was evaluated by the microdilution method associated or not with aminoglycosides and antifungals. The ethanol extract and methanol fraction of P. calomelanos showed good activity against S. aureus when associated with aminoglycosides and with benzoilmetronidazol against species of the genus Candida. These results indicate that P. calomelanos should be studied as a possible source of natural products to combat bacteria and fungi either directly or by modulating the mechanisms of resistance of these microorganisms, enhancing the antimicrobial activity of these drugs and combating microbial resistance

Enhancement of antibiotic activity by Cordia verbenacea DC

Escherichia coli is known to produce enterotoxins whose properties and its role in diarrheal disease has been extensively investigated. Some species of Staphylococcus are often recognized as etiological agents of many animal and human opportunistic infections. This study is the first test of change in resistance of antibiotic activity by Cordia verbenacea DC. against multiresistant strains of Escherichia coli and Staphylococcus aureus. In this study, the hexane and methanol extract of Cordia verbenacea DC. were tested for antibacterial activity alone and in combination with aminoglycosides against bacterial strains. The synergy of the methanolic and hexane were verified by microdilution method. A synergistic effect of both extracts combined with the aminoglycosides was demonstrated. It is therefore suggested that the extracts from Cordia verbenacea DC. could be used as a source of natural products derived from this plant with resistance-modifying antibacterial activity, providing a new weapon against the problem of bacterial resistance to antibiotics.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Enhancement of antibiotic activity by Cordia verbenacea DC

Escherichia coli is known to produce enterotoxins whose properties and its role in diarrheal disease has been extensively investigated. Some species of Staphylococcus are often recognized as etiological agents of many animal and human opportunistic infections. This study is the first test of change in resistance of antibiotic activity by Cordia verbenacea DC. against multiresistant strains of Escherichia coli and Staphylococcus aureus. In this study, the hexane and methanol extract of Cordia verbenacea DC. were tested for antibacterial activity alone and in combination with aminoglycosides against bacterial strains. The synergy of the methanolic and hexane were verified by microdilution method. A synergistic effect of both extracts combined with the aminoglycosides was demonstrated. It is therefore suggested that the extracts from Cordia verbenacea DC. could be used as a source of natural products derived from this plant with resistance-modifying antibacterial activity, providing a new weapon against the problem of bacterial resistance to antibiotics.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Flora Das Cangas Da Serra Dos Carajás, Pará, Brasil: Commelinaceae

This study provides detailed descriptions, illustrations, and morphological comments of the nine species of Commelinaceae registered for the cangas of Serra dos Carajás, Pará state: Commelina benghalensis, C. erecta, C. obliqua, C. rufipes, Dichorisandra hexandra, D. villosula, Floscopa peruviana, Murdannia nudiflora, and Tripogandra diuretica. © 2016 JBRJ.6751291130

Influence of flock treatment with the antibiotic tylosin on poultry meat quality: results of a preliminary experiment

The veterinary antibiotic tylosin was administered to broilers at sub-therapeutic and therapeutic levels to study its effect on the quality of poultry breast meat. No statistically significant differences were observed in moisture content, pH, drip loss, colour and extent of lipid oxidation between the breast meat from treated and not treated birds. However, the cooking loss of the meat from the birds administered tylosin was significantly higher than that from the not treated ones. Additionally, the mean shear force of the breast meat was significantly lower for the sub-therapeutically treated broilers than for the not treated and the therapeutically treated ones. It was concluded that the level at which tylosin was administered to the broilers affected the quality of the breast meat, particularly its textural properties

Entanglement in the One-dimensional Kondo Necklace Model

We discuss the thermal and magnetic entanglement in the one-dimensional Kondo necklace model. Firstly, we show how the entanglement naturally present at zero temperature is distributed among pairs of spins according to the strength of the two couplings of the chain, namely, the Kondo exchange interaction and the hopping energy. The effect of the temperature and the presence of an external magnetic field is then investigated, being discussed the adjustment of these variables in order to control the entanglement available in the system. In particular, it is indicated the existence of a critical magnetic field above which the entanglement undergoes a sharp variation, leading the ground state to a completely unentangled phase.Comment: 8 pages, 13 EPS figures. v2: four references adde