Reflections on Plant and Soil Nematode Ecology: Past,Present and Future

The purpose of this review is to highlight key developments in nematode ecology from its beginnings to where it stands today as a discipline within nematology. Emerging areas of research appear to be driven by crop production constraints, environmental health concerns, and advances in technology. In contrast to past ecological studies which mainly focused on management of plant-parasitic nematodes, current studies reflect differential sensitivity of nematode faunae. These differences, identified in both aquatic and terrestrial environments include response to stressors, environmental conditions, and management practices. Methodological advances will continue to influence the role nematodes have in addressing the nature of interactions between organisms, and of organisms with their environments. In particular, the C. elegans genetic model, nematode faunal analysis and nematode metagenetic analysis can be used by ecologists generally and not restricted to nematologists.     

The concentrations of soluble HLA-G protein are elevated during mid-gestation and decreased in pre-eclampsia

The aim of our study was to investigate the dynamics of the alterations of soluble human leukocyte antigen-G (sHLA-G) concentrations in sera of healthy non-pregnant women, as well as healthy pregnant women and patients with pre-eclampsia. Thirty five patients with pre-eclampsia, 52 healthy pregnant women, and 24 healthy non-pregnant women were included in the study. Sera concentrations of sHLA-G protein were determined using the immunoenzymatic ELISA method. Statistical analysis was performed using ANOVA and Mann-Whitney U tests. The concentrations of sHLA-G protein in sera of pregnant women in the first, as well as the second and third, trimesters of normal pregnancy were significantly higher in comparison with healthy nonpregnant women. The sera concentrations of sHLA-G in pregnant women in the second trimester of pregnancy were significantly higher compared to the first and third trimesters. The concentrations of sHLA-G in sera of patients with pre-eclampsia were significantly lower than in pregnant women in the third trimester of physiological pregnancy. The results of our study suggest that normal physiological pregnancy is associated with elevated sera concentrations of sHLA-G molecule. The increased concentrations of sHLA-G molecule in mid-gestation could suggest a role for the protein in the second phase of a physiological invasion of extravillous cytotrophoblast to spiral arteries. Furthermore, the results could suggest a role for the decreased sera concentrations of sHLA-G in the pathogenesis of pre-eclampsia.     

Temperament and ovarian reproductive hormones in women: evidence from a study during the entire menstrual cycle

Personality and temperament were hypothesized to function as important factors affecting life history strategies. Recent research has demonstrated the association between temperamental traits and reproduction in humans, however, the underlying mechanisms are still poorly understood. This study presents evidence for an association between temperamental traits and woman's fecundity, as indicated by levels of ovarian steroid hormones during the menstrual cycle. On a large sample of urban, reproductive age women (n = 108) we demonstrated that activity, endurance and emotional reactivity are associated with levels of estrogen and with a pattern of change of progesterone levels. Women high in activity, high in endurance and low in emotional reactivity had up to twice as high estradiol levels and more favorable progesterone profiles as women low in activity, low in endurance and high in emotional reactivity. The temperamental traits we measured highly overlap with extraversion, neuroticism and negative emotionality that were reported to correlate with reproductive success. Our findings thus suggest a possible explanation for these relationships, linking personality and women's reproductive success through a hormonal pathway.     

Study on the influence of cranberry extract ?uravit S·O·S(?) on the properties of uropathogenic Escherichia coli strains, their ability to form biofilm and its antioxidant properties

Consumption of cranberries is known to exert positive health effects, especially against urinary tract infections. For this reason, presumably, they are widely used in folk medicine. Different aspects of cranberry phenolics activity were studied in individual papers but complex study in this matter is missing. The aim of the present study is to provide complex data concerning various aspects of cranberry extract activity. We studied the effects of subinhibitory concentrations of commercially available extract (?uravit S·O·S(?)) against two Escherichia coli strains isolated from urine of patients with pyelonephritis. Additionally the main extract anthocyanins were characterized. The activity of extract against lipid peroxidation and its radical scavenging ability were also assessed. ?uravit S·O·S(?) decreased the hydrophobicity of one of the studied E. coli strains, reduced swimming motility and adhesion to epithelial cells of both studied strains, it also limited the ability of bacteria to form biofilm. Expression of curli was not affected by cranberry extract, the assessment of P fimbriae expression was not reliable due to extract-induced agglutination of erythrocytes. Cranberry extract caused filamentation in both studied E. coli strains. It also showed pronounced antioxidant and radical scavenging properties. The properties of the studied cranberry extract show that it could be effectively used in prevention and/or elimination of urinary tract infections, specially the recurrent ones.     

Synthesis and antibacterial activity of desosamine-modified macrolide derivatives

Structural factors behind erm macrolide resistance were studied through synthesis of new macrolide derivates possessing truncated desosamine sugar moieties and subsequent determination of their antibacterial activity. Synthesized compounds with 2'-deoxy and 3'-desmethyl desosamine rings demonstrated decreased antibacterial activity on the native Staphylococcus aureus strain and were inactive against constitutively resistance S. aureus. The obtained results indicate that steric repulsion between the dimethylated A2058 and desosamine ring cannot be considered as a primary reason for erm-resistance.     

Microtubules: MEC-17 moonlights in the lumen

New research characterizes a tubulin acetyltransferase that acts inside the microtubule lumen and has two separable activities that greatly affect microtubule architecture and functionality.     

Modification of Salmonella Typhimurium motility by the probiotic yeast strain Saccharomyces boulardii

Background

Motility is an important component of Salmonella enterica serovar Typhimurium (ST) pathogenesis allowing the bacteria to move into appropriate niches, across the mucus layer and invade the intestinal epithelium. In vitro, flagellum-associated motility is closely related to the invasive properties of ST. The probiotic yeast Saccharomyces boulardii BIOCODEX (S.b-B) is widely prescribed for the prophylaxis and treatment of diarrheal diseases caused by bacteria or antibiotics. In case of Salmonella infection, S.b-B has been shown to decrease ST invasion of T84 colon cell line. The present study was designed to investigate the impact of S.b-B on ST motility.

Methodology/Principal Findings

Experiments were performed on human colonic T84 cells infected by the Salmonella strain 1344 alone or in the presence of S.b-B. The motility of Salmonella was recorded by time-lapse video microscopy. Next, a manual tracking was performed to analyze bacteria dynamics (MTrackJ plugin, NIH image J software). This revealed that the speed of bacterial movement was modified in the presence of S.b-B. The median curvilinear velocity (CLV) of Salmonella incubated alone with T84 decreased from 43.3 µm/sec to 31.2 µm/sec in the presence of S.b-B. Measurement of track linearity (TL) showed similar trends: S.b-B decreased by 15% the number of bacteria with linear tract (LT) and increased by 22% the number of bacteria with rotator tract (RT). Correlation between ST motility and invasion was further established by studying a non-motile flagella-deficient ST strain. Indeed this strain that moved with a CLV of 0.5 µm/sec, presented a majority of RT and a significant decrease in invasion properties. Importantly, we show that S.b-B modified the motility of the pathogenic strain SL1344 and significantly decreased invasion of T84 cells by this strain.

Conclusions

This study reveals that S.b-B modifies Salmonella''s motility and trajectory which may account for the modification of Salmonella''s invasion.     

Genetic distinctness of parthenogenetic forms of European Polydrusus weevils of the subgenus Scythodrusus

Abstract Among eight species of Polydrusus weevils which belong to subgenus Scythodrusus, at least two possess parthenogenetic forms: P. (S.) inustus and P. (S.) pilifer. Both of these species consist of dioecious populations in the Caspian area and of parthenogenetic populations in Eastern Europe (P. (S.) inustus), the Caucasus region (both species) and Middle Asia (P. (S.) pilifer). The origin of parthenogenesis in this subgenus is unresolved; however some data suggest that the parthenogenetic forms are of hybrid ancestry. The genetic distinctness of parthenogenetic Scythodrusus was assessed on the basis of COII, ITS2, EF1‐α and Wolbachiawsp, 16S ribosomal DNA, ftsZ and hcpA sequence comparisons. Both taxa turned out to be monophyletic for all markers, which is an evidence against hybridization of their dioecious ancestors. On the other hand, a high frequency of heterozygous P. (S.) inustus females suggests an origin resulting from hybridization between genetically distinct dioecious representatives of this species. Very similar strains of Wolbachia supergroup A were found in both species, indicating that they have been either inherited from a common ancestor or were transmitted between parthenogenetic Scythodrusus weevils and probably spread randomly across their ranges.