Changes of the corpus callosum in children who suffered perinatal injury of the periventricular crossroads of pathways

There is a high incidence of periventricular leukomalacia, caused by hypoxia-ischemia, in preterm infants. These lesions damage the periventricular crossroads of commissural, projection and associative pathways, which are in a close topographical relationship with the lateral ventricles. We explored to what extent abnormalities of echogenicity of the periventricular crossroads correlate with changes in size of the corpus callosum. Our study included nine infants (gestation from 26-41 weeks; birth weight between 938-4450 grams) with perinatal brain injury. Periventricular areas, which topographically correspond to the frontal, main and occipital crossroad, were readily visualized by cranial ultrasound scans, performed during the first two weeks after birth. Corpus callosum mediosagittal area measurements were performed using magnetic resonance images, acquired between the first and sixth postnatal month (postmenstrual age 40-49 weeks). We found a statistically significant correlation between the increased echogenicity in the crossroad areas and the decrease of the corpus callosum midsagittal area (p < 0.05). This supports the hypothesis that callosal fibers can be damaged, during growth through the periventricular crossroads of pathways.     

Prey detection in antlions: propagation of vibrational signals deep into the sand

Trap‐building antlion larvae detect their prey according to the substrate vibrations produced during movement of the prey on the sand surface. Although most studies are devoted to surface vibrational waves, in the present study, we determine the role of vibrations travelling through deeper sand layers. A behavioural experiment confirms that vibrational stimuli from prey insects on the surface of the sand stimulate the antlions buried in deeper sand layers to move towards the surface. Sand depth and particle size both have a strong effect on signal transmission. The damping coefficient (α₁₀) varies from 0.49 dB to 3.30 dB cm^?1 and depends on frequency (in the range from 100 to 300 Hz), particle size (from finest to coarse sand) and distance from the source of the vibrations. The deeper the sand, the narrower the frequency range of the signal becomes. Sand is a filter for higher frequencies. The smaller the sand particles, the more intense the filtering becomes. Fine sand with a mean sand particle size of 360 μm is a more efficient filter than coarse sand; consequently, high frequencies (> 2.5 kHz) are eliminated at a depth of 3 cm. Mean frequency depends on both depth and particle size. However, low frequency signals still propagate at a certain distance, which is biologically important in prey detection. Although the most efficient signal propagation appears to occur in coarse sand, it contains overly large particles that are inconvenient for relatively small antlion larvae. Predators seek a compromise between fine and coarse sand choosing medium sand.     

Collective behaviour of hemoglobin in dense solutions.

The formation of radical pairs of spin-labelled hemoglobin molecules (beta-93 cysteine) in a mixture with unlabelled hemoglobin of concentrations higher than the critical one [(5.7 less than c less than 6.3) mM/sigma per heme] is due to some kind of long-range order characterizing these solutions. Labelled molecules induce pertubation in an unlabelled hemoglobin solution of concentration higher than the critical one. The collective behaviour of unlabelled molecules gives rise to the formation of radical pairs of spin-labelled hemoglobin molecules. Such behaviour is dependent on the ligand bound at the heme iron (carbonmonoxide, oxygen, or water.)     

Functional studies of aegerolysin and MACPF‐like proteins in Aspergillus niger

Proteins of the aegerolysin family have a high abundance in Fungi. Due to their specific binding to membrane lipids, and their membrane‐permeabilization potential in concert with protein partner(s) belonging to a membrane‐attack‐complex/perforin (MACPF) superfamily, they were proposed as useful tools in different biotechnological and biomedical applications. In this work, we performed functional studies on expression of the genes encoding aegerolysin and MACPF‐like proteins in Aspergillus niger. Our results suggest the sporulation process being crucial for strong induction of the expression of all these genes. However, deletion of either of the aegerolysin genes did not influence the growth, development, sporulation efficiency and phenotype of the mutants, indicating that aegerolysins are not key factors in the sporulation process. In all our expression studies we noticed a strong correlation in the expression of one aegerolysin and MACPF‐like gene. Aegerolysins were confirmed to be secreted from the fungus. We also showed the specific interaction of a recombinant A. niger aegerolysin with an invertebrate‐specific membrane sphingolipid. Moreover, using this protein labelled with mCherry we successfully stained insect cells membranes containing this particular sphingolipid. Our combined results suggest, that aegerolysins in this species, and probably also in other aspergilli, could be involved in defence against predators.     

1,2,3,4-Tetrahydroisoquinoline Derivatives as a Novel Deoxyribonuclease I Inhibitors

Herein we report an assessment of 24 1,2,3,4-tetrahydroisoquinoline derivatives for potential DNase I (deoxyribonuclease I) inhibitory properties in vitro. Four of them inhibited DNase I with IC₅₀ values below 200 μM. The most potent was 1-(6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolin-1-yl)propan-2-one ( 2 ) (IC₅₀=134.35±11.38 μM) exhibiting slightly better IC₅₀ value compared to three other active compounds, 2-[2-(4-fluorophenyl)-1,2,3,4-tetrahydroisoquinolin-1-yl]-1-phenylethan-1-one ( 15 ) (IC₅₀=147.51±14.87 μM), 2-[2-(4-fluorophenyl)-1,2,3,4-tetrahydroisoquinolin-1-yl]cyclohexan-1-one ( 18 ) (IC₅₀=149.07±2.98 μM) and 2-[6,7-dimethoxy-2-(p-tolyl)-1,2,3,4-tetrahydroisoquinolin-1-yl]cyclohexan-1-one ( 22 ) (IC₅₀=148.31±2.96 μM). Cytotoxicity assessment of the active DNase I inhibitors revealed a lack of toxic effects on the healthy cell lines MRC-5. Molecular docking and molecular dynamics simulations suggest that interactions with Glu 39, His 134, Asn 170, Tyr 211, Asp 251 and His 252 are an important factor for inhibitors affinity toward the DNase I. Observed interactions would be beneficial for the discovery of new active 1,2,3,4-tetrahydroisoquinoline-based inhibitors of DNase I, but might also encourage researchers to further explore and utilize potential therapeutic application of DNase I inhibitors, based on a versatile role of DNase I during apoptotic cell death.     

Qualitative study of Mollusca communities in the Serbian Danube stretch (river km 1260–863.4)

First detailed limnological study was performed from April 2003 to June 2008 in a 396.6 km long section of the Serbian Danube (divided in three parts; from 1260 r-km to 863.4 r-km) to examine community composition and spatial distribution of Mollusca with special attention to the expansion of Ponto-Caspian species, propagation of invasive and introduced species and occurrence of endemic species. Mollusca samples were collected at 15 sites in April, June, September and November. We investigated the spatial distributions and calculated the faunistic similarity of localities with respect to the community composition using the Sørensen Quotient of Similarity. Site variation in analyzed qualitative traits was examined using correspondence analysis. Additionally, the obtained Complete Linkage City-block (Manhattan) distances among sites/parts were subjected to UPGMA (unweighted pair-group method using arithmetic averages) cluster analysis. The class Gastropoda was represented by 18 species from two subclasses (Prosobranchia — six families and Pulmonata — three families).The class Bivalvia was represented by 15 species from four families of order Eulamellibranchiata. Mollusca were represented by 33 species belonging to 17 genera and 13 families. Out of five recorded Ponto-Caspian species in the studied Danube stretch, Lithoglyphus naticoides (Pfeiffer, 1828) and Dreissena polymorpha (Pallas, 1771) are assumed to be invasive species with the highest occurrence frequency (F = 1, each). Four new species in invertebrate fauna for the Danube, denoted as the introduced species — Neozoa, were identified: Theodoxus fluviatilis (L., 1758), Corbicula fluminalis (Müller, 1774), C. fluminea (Müller, 1774), and Sinanodonta woodiana (Lea, 1834). The only endemic species of Gastropoda found in the Danube was Viviparus acerosus Bourguignat, 1862.     

Barriers and errors in the implementation of community psychiatry in Slovenia

Background Slovenian psychiatry is predominantly hospital based. A programme for the development of general community psychiatric services was proposed to improve access to and quality and comprehensiveness of psychiatric care according to the modern standards of delivery of psychiatric services.Aim The aim of the paper is to present the programme for developing community services that was proposed to the Slovenian government, and to describe the barriers to its implementation that were encountered, as well as the errors made by the programme authors, that contributed to the rejection of the programme last year.Conclusions There are historical, political, professional and service organisation characteristics that impede the development of community psychiatry in Slovenia. These are to be addressed through coordinated action involving primary care professionals, non-government organisations with service users and carers, the Health Insurance Agency and politicians involved in the planning of health services.     

Molecular analysis of Leptospira spp. isolated from humans by restriction fragment length polymorphism, real-time PCR and pulsed-field gel electrophoresis

A total of 17 Leptospira clinical strains isolated from humans in Croatia were serologically and genetically analysed. For serovar identification, the microscopic agglutination test (MAT) and pulsed-field gel electrophoresis (PFGE) were used. To identify isolates on genomic species level, PCR-based restriction fragment length polymorphism (RFLP) and real-time PCR were performed. MAT revealed the following serogroup affinities: Grippotyphosa (seven isolates), Icterohaemorrhagiae (eight isolates) and Javanica (two isolates). RFLP of PCR products from a 331-bp-long fragment of rrs (16S rRNA gene) digested with endonucleases MnlI and DdeI and real-time PCR revealed three Leptospira genomic species. Grippotyphosa isolates belonged to Leptospira kirschneri , Icterohaemorrhagiae isolates to Leptospira interrogans and Javanica isolates to Leptospira borgpetersenii . Genomic DNA from 17 leptospiral isolates was digested with NotI and SgrAI restriction enzymes and analysed by PFGE. Results showed that seven isolates have the same binding pattern to serovar Grippotyphosa, eight isolates to serovar Icterohaemorrhagiae and two isolates to serovar Poi. Results demonstrate the diversity of leptospires circulating in Croatia. We point out the usefulness of a combination of PFGE, RFLP and real-time PCR as appropriate molecular methods in molecular analysis of leptospires.