Organization,development, and effects of infraorbital nerve transection on galanin binding sites in the trigeminal brainstem complex

Previous experiments from this laboratory have indicated that transection of the infraorbital nerve (ION, the trigeminal \[V] branch that supplies the mystacial vibrissae follicles) at birth and in adulthood has markedly different effects on galanin immunoreactivity in the V brainstem complex. Adult nerve transection increases galanin immunoreactivity in the superficial layers of V subnucleus caudalis (SpC) only, while neonatal nerve transection results in increased galanin expression in vibrissae-related primary afferents throughout the V brainstem complex. The present study describes the distribution of binding sites for this peptide in the mature and developing V ganglion and brainstem complex and determines the effects of neonatal and adult ION damage and the associated changes in galanin levels upon their distribution and density. Galanin binding sites are densely distributed in all V brainstem subnuclei and are particularly dense in V subnucleus interpolaris and the superficial layers of SpC. They are present at birth (P-0) and their distribution is similar to that in adult animals. Transection of the ION in adulthood and examination of brainstem 7 days later indicated marked reductions in the density of galanin binding sites in the V brainstem complex. With the exception of the superficial laminae of SpC, the same reduction in density remained apparent in rats that survived 45 days after nerve cuts. Transection of the ION on P-0 resulted in no change in the density of galanin binding sites in the brainstem after either 7 or 60 days survival. These results indicate that densely distributed galanin binding sites are present in the V brainstem complex of both neonatal and adult rats, that they are located in regions not innervated by galanin-positive axons, and that their density is not significantly influenced by large lesion-induced changes in the primary afferent content of their natural ligand.     

Spatial summation of heat induced pain within and between dermatomes

The aim was to study spatial summation within and between ipsi- and contralateral dermatomes at different painful temperatures. For heat stimulation we used a computer controlled thermofoil based thermode. The thermode area could be varied in five discrete steps from 3.14 to 15.70 cm2. When we applied the stimuli within a dermatome, the mean heat pain threshold decreased significantly from 45.6 to 43.5 C as the area was increased from minimum (3.14 cm2) to maximum (15.70 cm2). When the areas were increased involving different dermatomes (both ipsi- or contralateral), we found similar decreases in pain threshold. Spatial summation was also found within and between dermatomes at supra-threshold temperatures (46, 48, 50 C).The study shows that spatial summation of pain is most likely a mechanism acting across segments and is existing from pain threshold to tolerance.     

The Central Projections of the Monkey Tooth Pulp Afferent Neurons

Transganglionic transport of horseradish peroxidase conjugated to wheatgerm agglutinin (HRP:WGA) entrapped in hypoallergenic polyacrylamide gel was used to study the patterns of termination of primary afferents that innervate the upper and lower tooth pulps within the trigeminal sensory nuclear complex (TSNC) of the monkey. HRP:WGA injections were also made into the lower incisors and molars, in order to examine the topographic arrangement of pulpal afferent projections. HRP-labeled pulpal afferents innervating lower and upper teeth projected ipsilaterally to the rostral subnucleus dorsalis (Vpd) and caudal subnucleus ventralis (Vpv) of the nucleus principalis (Vp); the rostrodorsomedial (Vo.r) and dorsomedial (Vo.dm) subdivisions of the nucleus oralis (Vo); the dorsomedial subdivision of the nucleus interpolaris (Vi); and laminae I—II and/or V of the nucleus caudalis (Vc) at its rostralmost level. The HRP-labeled terminals from upper and lower pulpal afferents formed a rostrocaudal column from the midlevel of Vp to the rostral tip of Vc. The label in Vp and Vo was considerably dense, but the column of terminals was interrupted at the Vpd-Vpv transition. The label in Vi and Vc was much less dense compared to that in the rostral nuclei, and the column of terminals was interrupted frequently. The representation of the upper and lower teeth in TSNC was organized in a somatotopic fashion that varied from one subdivision to the next, though their terminal zones overlapped within Vpd. The upper and lower teeth were represented in Vpv, Vo.r, Vo.dm, Vi, and Vc in a ventrodorsal, dorsoventral, lateromedial, lateromedial, and lateromedial sequence, respectively. Topographic arrangement was also noticed for the projections of pulpal afferents from the lower incisors and molars: The representations of the lower incisors and molars in Vpv, Vo.r, Vo.dm, Vi, and Vc were organized in a lateromedial, dorsoventral, ventrodorsal, ventrodorsal, and lateromedial sequence, respectively. The present results indicating sparse projections from pulpal afferents in the monkey's Vc are in good correspondence with a clinical report that trigeminal tractotomy just rostral to the obex has no significant effect on dental pain perception in patients. Furthermore, the present study indicates that projection patterns of pulpal afferents—which include the termination sites, the density of terminations between nuclei, and topographic arrangement—differ among animal species.     

Health applications of bioactive compounds from marine microalgae

Marine microalgae and cyanobacteria are very rich in several chemical compounds and, therefore, they may be used in several biological applications related with health benefits, among others. This review brings the research up-to-date on the bioactive compounds produced by marine unicellular algae, directly or indirectly related to human health. It covers and goes through the most studied applications of substances such as PUFA, sterols, proteins and enzymes, vitamins and pigments, in areas so diverse as human and animal nutrition, therapeutics, and aquaculture. The great potential of marine microalgae and the biocoumpounds they produce are discussed in this review.     

The Roma in Macedonia: Ethnic politics and the marginal condition in a Balkan state

Most of Eastern Europe's five‐to‐seven‐million Roma (Gypsies) welcomed the revolutions of 1989 only to realize that the post‐communist era brought mixed blessing to them. Although since then their political and cultural marginalization had diminished, their social and economic circumstances had clearly deteriorated in East Central Europe and the Balkans alike. The only exception to this rule appears to be the newly independent Republic of Macedonia, where the Roma's conditions in many respects are far superior to those of their counterparts elsewhere in the region. There are several reasons for this phenomenon. In the economic realm the Macedonian Roma's situation has also worsened (although still much better than that of the Roma in other Balkan states) but not as a result of ethnic discrimination but owing to the economic hardships accompanying the post‐communist transitions. In the political sphere, the Roma in Macedonia have benefited from a state whose representatives are willing to rise above sympathetic rhetoric and take concrete steps to alleviate their problems as well as from relatively well organized Romani political parties. Most important, however, are the differences between societal attitudes towards the Roma in Macedonia and elsewhere in Eastern Europe. In Macedonia the Roma's relations with the dominant ethnic group (Macedonians) are primarily characterized by ‘peaceful coexistence’ rather than tension and animosity. Moreover, Romani communities in Macedonia are less isolated from non‐Roma both culturally and socio‐economically. This state of affairs is the result of a number of related factors, most important of which are that the Romani community does not represent a threat to Macedonians given their numerical weakness and lack of political clout in contradistinction to the very real threat posed by the ethnic Albanian community in the country. In turn, the Roma's relations to ethnic Albanians and Turks remain relatively agreeable as well.     

Abundance and Diversity of Ammonia-Oxidizing Bacteria and Archaea in Cold Springs on the Qinghai-Tibet Plateau

The cold springs underlain by gas hydrates on the Qinghai-Tibet Plateau (QTP) are similar to deep-sea cold seeps with respect to methane biogeochemistry. Previous studies have shown that ammonia oxidizing bacteria (AOB) and archaea (AOA) are actively present and play important roles in the carbon/nitrogen cycles in cold seeps. Studying AOA and AOB communities in the QTP cold springs will be of great importance to our understanding of carbon and nitrogen cycling dynamics related to the underlying gas hydrates on the QTP. Thus, the abundance and diversity of AOB and AOA in sediments of four cold springs underlain by gas hydrates on the QTP were determined by using quantitative polymerase chain reaction and amoA gene (encoding ammonia monooxygenase involved in ammonia oxidation) phylogenetic analysis. The results showed that the AOB and AOA amoA gene abundances were at 10³–10⁴ copies per gram of the sediments in the investigated cold springs. The AOB population consisted of Nitrosospira and Nitrosomonas in contrast with the mere presence of Nitrosospira in marine cold seeps. The AOB diversity was higher in cold springs than in cold seeps. The AOA population was mainly composed of Nitrososphaera, in contrast with the dominance of Nitrosopumilus in cold seeps. The terrestrial origin and high level of dissolved oxygen of the cold springs may be the main factors accounting for the observed differences in AOB and AOA populations between the QTP cold springs and marine cold seeps.     

Niche Separation of Methanotrophic Archaea (ANME-1 and -2) in Methane-Seep Sediments of the Eastern Japan Sea Offshore Joetsu

In this study, we investigated the diversity and spatial distribution of anaerobic methanotrophic archaea (ANMEs) in sediments of a gas hydrate field off Joetsu in the Japan Sea. Distribution of ANMEs in sediments was identified by targeting the gene for methyl coenzyme M reductase alpha subunit (mcrA), a phylogenetically conserved gene that occurs uniquely in methanotrophic and methanogenic archaea, in addition to 16S rRNA genes. Quantitative PCR analyses of mcrA genes in 14 piston core samples suggested that members of ANME-1 group would dominate AOM communities in sulfate-depleted sediments, even below the sulfate-methane interface, while ANME-2 archaea would prefer to populate in shallower sediments containing comparatively higher sulfate concentrations. These results suggest that, although the potential electron acceptors in sulfate-depleted habitats remain elusive, the niche separation of ANME-1 and -2 may be controlled by in situ concentration of sulfate and the availability in sediments.     

Lower Abundance of Ammonia-Oxidizing Archaea Than Ammonia-Oxidizing Bacteria Detected in the Subsurface Sediments of the Northern South China Sea

Diversity and abundance of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in samples of the northern South China Sea subsurface sediment were assessed by analyzing the amoA gene sequences retrieved from the samples. The microbial diversity was assessed using rarefaction and phylogenetic analyses. The deep-sea subsurface sediments harbored diverse and distinct AOA and AOB communities, but the abundance of AOA was lower than that of AOB, consistent with many other studies about bacteria and archaea in subsurface sediments. Diversity of AOA shown in the OTUs and Shannon index was correlated with the concentration of nitrite in the Pearson analysis, but no obvious relationships between the diversity or abundance of AOB and the physicochemical parameters could be identified in the present study, indicating the concentration of ammonium may not be an important factor to determine the diversity and abundance of ammonia-oxidizing prokaryotes in the subsurface sediments. Additionally, Nitrosomonas-like AOB was found to be dominant in subsurface sediments of the northern South China Sea showing a different adaption strategy comparing with some Nitrosospira-like AOB lineages. Concentration of nitrite was correlated with diversity of AOA, but no correlations between diversity and abundance of AOB and the physicochemical parameters were established in the study. Supplementary materials are available for this article. Go to the publisher's online edition of Geomicrobiology Journal to view the free supplemental files.     

Micrometric segregation of fluorescent membrane lipids: relevance for endogenous lipids and biogenesis in erythrocytes

Micrometric membrane lipid segregation is controversial. We addressed this issue in attached erythrocytes and found that fluorescent boron dipyrromethene (BODIPY) analogs of glycosphingolipids (GSLs) [glucosylceramide (BODIPY-GlcCer) and monosialotetrahexosylganglioside (GM1BODIPY)], sphingomyelin (BODIPY-SM), and phosphatidylcholine (BODIPY-PC inserted into the plasma membrane spontaneously gathered into distinct submicrometric domains. GM1BODIPY domains colocalized with endogenous GM1 labeled by cholera toxin. All BODIPY-lipid domains disappeared upon erythrocyte stretching, indicating control by membrane tension. Minor cholesterol depletion suppressed BODIPY-SM and BODIPY-PC but preserved BODIPY-GlcCer domains. Each type of domain exchanged constituents but assumed fixed positions, suggesting self-clustering and anchorage to spectrin. Domains showed differential association with 4.1R versus ankyrin complexes upon antibody patching. BODIPY-lipid domains also responded differentially to uncoupling at 4.1R complexes [protein kinase C (PKC) activation] and ankyrin complexes (in spherocytosis, a membrane fragility disease). These data point to micrometric compartmentation of polar BODIPY-lipids modulated by membrane tension, cholesterol, and differential association to the two nonredundant membrane:spectrin anchorage complexes. Micrometric compartmentation might play a role in erythrocyte membrane deformability and fragility.     

Acyl Transfer from Membrane Lipids to Peptides Is a Generic Process

The generality of acyl transfer from phospholipids to membrane-active peptides has been probed using liquid chromatography–mass spectrometry analysis of peptide–lipid mixtures. The peptides examined include melittin, magainin II, PGLa, LAK1, LAK3 and penetratin. Peptides were added to liposomes with membrane lipid compositions ranging from pure phosphatidylcholine (PC) to mixtures of PC with phosphatidylethanolamine, phosphatidylserine or phosphatidylglycerol. Experiments were typically conducted at pH 7.4 at modest salt concentrations (90 mM NaCl). In favorable cases, lipidated peptides were further characterized by tandem mass spectrometry methods to determine the sites of acylation. Melittin and magainin II were the most reactive peptides, with significant acyl transfer detected under all conditions and membrane compositions. Both peptides were lipidated at the N-terminus by transfer from PC, phosphatidylethanolamine, phosphatidylserine or phosphatidylglycerol, as well as at internal sites: lysine for melittin; serine and lysine for magainin II. Acyl transfer could be detected within 3 h of melittin addition to negatively charged membranes. The other peptides were less reactive, but for each peptide, acylation was found to occur in at least one of the conditions examined. The data demonstrate that acyl transfer is a generic process for peptides bound to membranes composed of diacylglycerophospholipids. Phospholipid membranes cannot therefore be considered as chemically inert toward peptides and by extension proteins.