3-D ultrastructural distribution of collagen in human placental villi at term in relation to vascular tree

In order to understand the 3-D distribution of collagen in relation to vascularization, chorionic villi of human placentae, belonging to normal pregnancies at term, were studied by scanning electron microscopy (SEM) after alkali maceration techniques, and by transmission electron microscopy (TEM). The villous tree appeared made of an uninterrupted structure of collagen fibres. The collagen fibres connected the chorionic villi axis with their basal plates and organised differently according to the various levels of villous branching. The collagen of stem villi showed copious fibres. The external fibres (facing the villous surface) were arranged mainly longitudinally. The central core of the villi (inner fibres) were arranged concentrically around the wall of the fetal vessels. Both external and internal fibres formed stratified lamellae or small parallel bundles. The inner core of stem villi showed small holes housing capillary spaces. Mature intermediate and terminal villi showed a scarce amount of collagen arranged in thin concentric layer within the villous core, surrounding numerous dilated capillary and sinusoid spaces.These observations demonstrated that the extracellular matrix of human chorionic villi is highly compartmentalised and shows a variable structural 3-D distribution depending on the branching level of the villous tree, such a distribution ensures the most favourable microenvironment for feto-maternal exchanges and it is likely able to provide a modulated support to the developing chorionic fetal vessels and trophoblastic layer as well.     

FTIR spectroscopy, chemical and histochemical characterisation of wood and lignin of five tropical timber wood species of the family of Dipterocarpaceae

The goal of this study was to characterise chemical and histochemical properties of five dipterocarp timber wood species (Dipterocarpus kerrii, Hopea plagata, Parashorea malaanoman, Shorea almon, and Shorea contorta) differing in wood service life and utilisation. Wood of H. plagata, the most durable species, contained the lowest concentrations of nitrogen and ligno-protein, the highest C/N ratio and the lowest lignin concentration per dry mass but the highest lignin and extractive concentrations per wood density. FTIR spectroscopic studies of wood and isolated lignins of D. kerrii and H. plagata revealed differences compared to P. malaanoman and Shorea sp., which are species with short service life. Lignins of the Shorea/Parashorea species had a higher G/S ratio than those of H. plagata and D. kerrii. This was also evident from histochemical staining. Principle component analysis of FTIR spectra identified differences in both lignin composition and ligno-protein content as major source of variation.     

Differential regulation of protein synthesis in skeletal muscle and liver of neonatal pigs by leucine through an mTORC1-dependent pathway

Neonatal growth is characterized by a high protein synthesis rate that is largely due to an enhanced sensitivity to the postprandial rise in insulin and amino acids, especially leucine. The mechanism of leucine’s action in vivo is not well understood. In this study, we investigated the effect of leucine infusion on protein synthesis in skeletal muscle and liver of neonatal pigs. To evaluate the mode of action of leucine, we used rapamycin, an inhibitor of mammalian target of rapamycin (mTOR) complex-1 (mTORC1). Overnight-fasted 7-day-old piglets were treated with rapamycin for 1 hour and then infused with leucine (400 μmol·kg -1 ·h -1 ) for 1 hour. Leucine infusion increased the rate of protein synthesis, and ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor (eIF) 4E-binding protein-1 (4E-BP1) phosphorylation in gastrocnemius and masseter muscles (P < 0.05), but not in the liver. The leucine-induced stimulation of protein synthesis and S6K1 and 4E-BP1 phosphorylation were completely blocked by rapamycin, suggesting that leucine action is by an mTORC1-dependent mechanism. Neither leucine nor rapamycin had any effect on the activation of the upstream mTORC1 regulators, AMP-activated protein kinase and protein kinase B, in skeletal muscle or liver. The activation of eIF2a and elongation factor 2 was not affected by leucine or rapamycin, indicating that these two pathways are not limiting steps of leucine-induced protein synthesis. These results suggest that leucine stimulates muscle protein synthesis in neonatal pigs by inducing the activation of mTORC1 and its downstream pathway leading to mRNA translation.     

Incidence of ‘Candidatus Liberibacter europaeus’ and phytoplasmas in Cacopsylla species (Hemiptera: Psyllidae) and their host/shelter plants

Psyllids, as vectors of phloem-restricted plant pathogens, are serious agricultural pests. Fruit tree phytoplasmas are transmitted by different Cacopsylla spp., while other psyllids are known vectors of liberibacters. Recently, the bacterium ??Candidatus Liberibacter europaeus?? was found in pear trees and in Cacopsylla pyri (Linnaeus), the vector of ??Ca. Phytoplasma pyri??. This new species does not cause symptoms in plants and is probably a symbiont rather than a pathogen. Based on these findings and the assumption that ??Ca. Liberibacter europaeus?? is widespread, we studied its distribution in the genus Cacopsylla and in the respective host and shelter plants (where psyllids aestivate and overwinter), as well as its possible co-presence with ??Ca. Phytoplasma?? spp. We tested 14 Cacopsylla species and 11 plant species from northwestern Italy, Hungary and Israel, characterized by warm oceanic, temperate continental and warm Mediterranean climatic conditions, respectively. ??Ca. Liberibacter europaeus?? was common within the Cacopsylla genus, being present in nine of the 14 species screened as well as in most host plants, whereas none of the shelter plants tested positive for this bacterium. Altogether, these findings indicate the presence of ??Ca. Liberibacter europaeus?? in continental zones, whereas it does not seem to be widespread in the Mediterranean region. Furthermore, lack of specific symptoms in all infected plants confirms an endophytic relationship with this bacterium, while its abundance in insects suggests a beneficial role for the host. Co-infections with phytoplasmas, observed in insects and plants, require further study to evaluate the possible interactions between them.     

Effects of gamma-irradiation on the free radical and antioxidant contents in nine aromatic herbs and spices

Nine spice and aromatic herb samples (i.e., basil, bird pepper, black pepper, cinnamon, nutmeg, oregano, parsley, rosemary, and sage) were gamma-irradiated at a dose of 10 kGy according to commercial practices. The effects of the disinfection treatment on the content of organic radicals and some nutrients (namely, vitamin C and carotenoids) in the samples were investigated by chromatographic and spectroscopic techniques. Irradiation resulted in a general increase of quinone radical content in all of the investigated samples, as revealed by electron paramagnetic resonance spectroscopy. The fate of these radicals after storage for 3 months was also investigated. The cellulose radical was clearly observed in a few samples. Significant losses of total ascorbate were found for black pepper, cinnamon, nutmeg, oregano, and sage, whereas a significant decrease of carotenoids content was observed for cinnamon, oregano, parsley, rosemary, bird pepper, and sage.     

Concentration of Lamellar Bodies and the Lecithin/Sphingomyelin Ratio in Equine Amniotic Fluid at the Time of Delivery

Veterinary Research Communications -     

Composition,abundance and phytoplasma infection in the hawthorn psyllid fauna of northwestern Italy

Hawthorn (Crataegus monogyna) is one of the natural hosts of Cacopsylla melanoneura, the acknowledged vector of ‘Candidatus Phytoplasma mali’, the causal agent of Apple Proliferation disease, a serious and growing problem for apple production in Europe, particularly in northern Italy. Wild plants could be important sources of both insects and phytoplasmas, but their role in the epidemiology of phytoplasma diseases and their insect vectors has never been thoroughly examined. Cacopsylla melanoneura’s primary host is hawthorn, a plant closely related to apple which often grows wild near orchards. Other psyllid species feed on hawthorn, but no data are available on their possible role as phytoplasma vectors. We investigated the hawthorn’s psyllid fauna in northwestern Italy using yellow sticky traps, beat trays, and molecular analyses from 2003–2005, to study the relationship between hawthorn, the phytoplasma and the insect vector. Population dynamics were monitored, and insects and hawthorn samples were analysed by polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and DNA sequencing for the presence of phytoplasmas. Cacopsylla melanoneura was the dominant psyllid species, followed by C. peregrina, C. affinis and C. crataegi. PCR and RFLP analyses revealed the presence of different fruit tree phytoplasmas in hawthorn plants, and in all four psyllid species.     

Mechanoreceptors in the medial and lateral glenohumeral ligaments of the canine shoulder joint.

In order to have a better understanding of the role of ligaments in canine shoulder joint stability, the presence of mechanoreceptors in the medial (MGHL) and lateral (LGHL) glenohumeral ligaments was detected by means of a modified gold chloride stain. Three morphologically distinct mechanoreceptors were identified: Ruffini receptors (type I endings), Pacinian corpuscles (type II endings) and Golgi tendon organ-like receptors (type III endings). These receptors are mainly localized at each end of the ligaments and are prevalently in their glenoid portion. In particular, in the MGHL the highest density was at the cranial arm of the insertion into the scapula. The variety of mechanoreceptors in canine shoulder ligaments might indicate an afferent function in providing the CNS with joint proprioceptive information. Therefore, besides acting as passive mechanical stabilizers, the MGHL and the LGHL may serve as sensory structures, contributing actively to joint stability. Ligamentous injuries which occur in shoulders not only affect mechanical restraint but also alter the proprioceptive input to the CNS by means of disruption of the mechanoreceptors.