Possible Involvement of Endothelin Peptides and L-Arginine-Nitric Oxide Pathway on the Effect of Endotoxin in the Rabbit Isolated Perfused Kidney

Escherichia coli endotoxin (LPS) when infused through the renal artery of the rabbit isolated perfused kidney prepared as constant pressure mode, caused a decrease in flow rate and kidney weight indicating its primary vasoconstrictor effect. This effect was predominant in kidneys from rabbits pretreated with LPS. Endothelin-1 at a concentration of 10−10 M and big endothelin-1 at a concentration of 10−8 M produced equal vasoconstrictor effects in kidney. Addition of endotheHn converting enzyme inhibitor, phosphoramidon, to the perfusion medium at a concentration of 10−6 M caused a reduction in the effects of both LPS and big ET-1 without altering the vasoconstrictor effect of ETol. However, addition of methylene blue (10−5 M), a soluble guanylate cyclase inhibitor and NG-nitro-L-arginine-methyl ester (10−6 M) to the perfusion medium caused a potentiation in the vasoconstrictor effect of LPS. Indomethacin at a concentration of 10−6 M did not alter the effect of LPS. These results were taken as evidence for the participation of endothelin peptides and the L-arginine-nitric oxide pathway in the effect ofLPS in rabbit isolated perfused kidney

Türk toplumunda gözlenen ilk hemoglobin g-waimanalo ve hemoglobin fontainebleau olguları]

[No abstract available

Allelopathic potential of macrofungi on germinating maize (Zea mays L.) grain

The effect of methanol extracts of 10 macrofungi was evaluated on grain germination of maize (Zea mays L.). Germination percentage, radicle and plumule length and the level of carbohydrates and fatty acids were measured. Fungal metabolites inhibited germination up to 90.96%, plumule (97.77%) and radicle (92.83%) development. Plumule and radicle lengths were stimulated 35.26 and 10.60% in some assays, respectively. The fungal metabolites decreased the glucose (97.60%), sucrose (90.34%), fructose (96.85%), maltose (95.64%), oleic acid (97.50%) and linoleic acid (98.25%) levels, whereas increasing levels of the glucose (165.14%), sucrose (166.53%), fructose (83.18%), maltose (124.73%), oleic acid (6975.00%) and linoleic acid (5233.33%) were detected in some assays. It is concluded that macrofungi metabolites have commonly inhibitory effects on physiological and morphological processes of germinating maize grain except for considerable increases in the some parameters investigated

Musculoskeletal sonography in juvenile systemic lupus erythematosus

PubMedWo

Palmitoylation of xanthan polysaccharide for self-assembly microcapsule formation and encapsulation of cells in physiological conditions

Hydrophobized polysaccharides have emerged as a promising strategy in the biomedical field due to the versatility to design functional structures through the spontaneous self-assembly in cell-friendly conditions. Based on this concept, xanthan, a bacterial extracellular polysaccharide with potential as encapsulating matrix, was conjugated with hydrophobic palmitoyl groups to obtain an amphiphilic system able to form capsules by self-assembly processes. The conjugation of xanthan was performed at different xanthan/palmitoyl chloride ratios and Fourier transformed infrared, 1H nuclear magnetic resonance spectroscopies, as well as wide angle X-ray diffraction, differential scanning calorimetry were performed to characterize the obtained conjugates. The results showed that the increase in the hydrophobic reactant promoted higher hydrophobic interaction and consequently higher molecular organization. At certain palmitoyl concentrations and through a proper balance between charge repulsion and hydrophobic interaction, the amphiphilic molecules self-assembled into stable capsular hollow structures in the presence of physiological ion concentration and pH. Poly-L-lysine coated microcapsules with an average diameter of 576.6 _ 74 mm and homogenous size distribution were obtained. The morphology revealed by scanning electron microscopy showed microcapsules with two distinct layers. The ability of palmitoyl-xanthan microcapsules to sustain viability and proliferation of encapsulated cells was confirmed by AlamarBlue and DNA assays. These findings suggest the application of palmitoyl-xanthan microcapsules as a potential material for cell encapsulation in cellbased therapies.This work was supported by the European Union funded project "Find and Bind" (NMP4-SL-2009-229292) under FP7. A. C. Mendes thanks the Portuguese Foundation for Science Technology for a PhD grant (SFRH/BD/42161/2007). We thank Emanuel Fernandes of the 3B's Research Group at the University of Minho for his assistance with DSC analysis

Effect of aging on H-reflex response to fatigue

Injury as a result of tripping is relatively common among older people. The risk of falling increases with fatigue and of importance is the ability to dorsiflex the foot through timely activation of the tibialis anterior (TA) muscle to ensure the foot clears the ground, or an obstacle, during the swing phase of walking. We, therefore, questioned whether the muscle spindle input to the motoneurons alters with ongoing fatigue in older people. We electrically stimulated the common peroneal nerve to assess the TA primary afferent efficacy using H-reflex before, immediately following and after a fatiguing maximal isometric contraction. M-response was kept unchanged throughout the experiment to ensure a similar stimulus intensity was delivered across time points. H-reflex increased significantly while the TA muscle was in a state of fatigue for the younger participants but tended to decrease with increasing age. The main contributor to the tonicity of TA muscle, i.e., excitatory synapses of spindle primary endings of motoneurons that innervate TA muscle, tend to lose their efficacy during fatigue in the older individuals but increased efficiency in the majority of the younger people. Since TA muscle is the main dorsiflexor of the foot and it needs to be active during the swing phase of stepping to prevent tripping, older individuals become more susceptible to falling when their muscles are fatigued. This finding may help improve devices/treatments to overcome the problem of tripping among older individuals