Population-genetic study of Balkan endemic nephropathy in Serbia

The study of Balkan endemic nephropathy (BEN) in the affected localities of southern Serbia shows population-genetic difference between samples of BEN affected individuals and control group consisting of non-affected individuals from the same localities. Detailed population-genetic study in village Chepure, which includes 20 large families where BEN is present in 646 (from first to fourth degree) relatives of probands, shows a familial character of disease as well as significant genetic influences in expression of the illness. Our study of genetic homozygosity degree includes an analysis of the presence, distribution and individual combination of 20 to 30 selected genetically controlled morphophysiological traits in the sample of BEN patients and in the control-healthy group. Assuming that BEN is genetically controlled disease, we made a hypothesis that an increased homozygosity level, as well as the changed variability among the patients, could be populationgenetic parameter for the prediction of the illness. Taking into consideration our experience, as well as the experience of numerous scientists who studied the nature of the inheritance of mono-and oligo-genically controlled qualitative traits, we applied a methodology to estimate the proportion of such homozygously recessive characters (HRC-test). This population-genetic study did not only show statistically significant difference of the mean values of genetic homozygosity (BEN: 8.7 ± 0.3; control: 7.6 ± 0.3), but of the differences in the type of distribution too, as well as the differences in the presence of certain individual combinations of such traits. The text was submitted by the authors in English.     

Population-genetic study of Balkan endemic nephropathy in Serbia

The study of Balkan Endemic Nephropathy (BEN) in the affected localities of southern Serbia shows population-genetic difference between samples of BEN affected individuals and control group consisting of non-affected individuals from the same localities. Detailed population-genetic study in village Chepure, which includes 20 large families where BEN is present in 646 (from first to fourth degree) relatives of probants, shows familial character of disease as well as significant genetic influences in expression of the illness. Our study of genetic homozygosity degree includes an analysis of the presence, distribution and individual combination of 20 to 30 selected genetically controlled morpho-physiological traits in the sample of BEN patients and in the control-healthy group. Assuming that BEN is genetically controlled disease, we made a hypothesis that an increased homozygosity level, as well as the changed variability among the patients, could be population-genetic parameter for the prediction of the illness. Taking into consideration our experience, as well as the experience of numerous scientists who studied the nature of the inheritance of mono- and oligo-genically controlled qualitative traits, we applied a methodology to estimate the proportion of such homozygously recessive characters (HRC-test). This population-genetic study did not only show statistically significant difference of the mean values of genetic homozygosity (BEN - 8.7 +/- 0.3; control - 7.6 +/- 0.3), but of the differences in the type of distribution too, as well as the differences in the presence of certain individual combinations of such traits.     

Genetic Variability in the Group of Patients with Congenital Hip Dislocation

Our study of genetic homozygosity degree includes an analysis of the presence, distribution, and individual combination of 20 selected genetically controlled morphophysiological traits in the group of patients (N = 93) with congenital hip dislocation (CDH) and in control sample consisting of schoolchildren from Belgrade (N = 200). Assuming that CDH is a genetically controlled disease, we made a hypothesis that an increased homozygosity level, as well as the changed variability among the patients, could be a population-genetic parameter for the prediction of the illness. Taking into consideration our experience, as well as the experience of numerous scientists who studied the nature of the inheritance of mono- and oligogenically controlled qualitative traits, we applied a methodology to estimate the proportion of such homozygously recessive characters (HRC-TEST). This population-genetic study did not only show statistically significant difference of the middle values of genetic homozygosity (CDH: 7.1 ± 0.2; control: 5.2 ± 0.1), but of the differences in the type of distribution too, as well as the differences in the presence of certain individual combinations of such traits. The described methodology can be used in further analyses, with hope that it can be applied as an early prognosis for decreased resistance to different diseases. The frequencies of ABO blood types in the sample of CDH patients were similar to the average value of the Serbian population, while the percentage of blood group A is slightly increased. Comparing frequencies of Rh blood groups, there is no difference between tested samples.__________From Genetika, Vol. 41, No. 8, 2005, pp. 1142–1146.Original English Text Copyright © 2005 by Cvjeticanin, Marinkovic.This text was submitted by the authors in English.     

Genetic variability in the group of patients with congenital hip dislocation

Our study of genetic homozygosity degree includes an analysis of the presence, distribution and individual combination of 20 selected genetically controlled morpho-physiological traits in the group of patients (N = 93) with congenital hip dislocation (CDH) and in control sample consisting of school children from Belgrade (N = 200). Assuming that CDH is genetically controlled disease, we made a hypothesis that an increased homozygosity level, as well as the changed variability among the patients, could be population-genetic parameter for the prediction of the illness. Taking into consideration our experience, as well as the experience of numerous scientists who studied the nature of the inheritance of mono- and oligo-genically controlled qualitative traits, we applied a methodology to estimate the proportion of such homozygously recessive characters (HRC-TEST). This population-genetic study did not only show statistically significant difference of the middle values of genetic homozygosity (CDH-7.1+/-0.2; control - 5.2+/-0.1), but of the differences in the type of distribution too, as well as the differences in the presence of certain individual combinations of such traits. The described methodology can be used in further analyses, with hope that it can be applied as an early prognosis for decreased resistance to different diseases. The frequencies of ABO blood types in the sample of CDH patients were similar to the average value of Serbian population, while the percentage of blood group A is slightly increased. Comparing frequencies of Rh blood groups, there is no difference between tested samples.     

Selection of a standard culture medium for primary culture of <Emphasis Type="Italic">Limulus polyphemus</Emphasis> Amebocytes

Summary This study provides information relevant to future research aimed at producing Limulus Amebocyte Lysate (LAL) in vitro, which would potentially reduce the need to harvest and bleed horseshoe crabs as in the current methods of LAL production. To address the need for primary culture of horseshoe crab amebocytes, this study tested the effects of a variety of standard insect cell culture media on amebocyte morphology and viability after 7 d of maintenance. Amerbocyte morphology was least altered from in vivo form in Grace’s Modified Insect Medium, with no observed degranulation of cells, as compared to the other media tested. There were significant differences in amebocyte viability among the six insect cell culture media tested. Grace’s Modified Insect Medium sustained viability of 77.2±5.1% (mean ± standard deviation) of amebocytes, followed distantly by Grace’s Insect Medium with 35.1±8.7% amebocyte viability. Results indicate that Grace’s Modified Insect Medium with horseshoe crab serum supplementation was the best candidate of the six media tested for future medium optimization for Limulus amebocyte requirements.     

A novel structural motif and structural trees for proteins containing it

In the present study, a novel structural motif that can be represented as a combination of the known βαβ-unit and ψ-motif is described and analyzed. In theory, there are four possible combinations of the motifs since each of them can exist in two forms, left-handed and right-handed. For this study, we have selected 140 nonhomologous proteins in which 158 combinations of such types have been found. The combination of the right-handed ψ-motif and the right-handed βαβ-unit has been shown to occur most often (87 cases out of 158) and the combination of the left-handed βαβ-unit and the left-handed ψ-motif does not occur at all. Three novel structural trees in which the commonly occurring combinations are taken as the root structures have been constructed.     

Genetic diversity and bottleneck studies in the Marwari horse breed

Genetic diversity within the Marwari breed of horses was evaluated using 26 different microsatellite pairs with 48 DNA samples from unrelated horses. This molecular characterisation was undertaken to evaluate the problem of genetic bottlenecks also, if any, in this breed. The estimated mean (± s.e.) allelic diversity was 5.9 (± 2.24), with a total of 133 alleles. A high level of genetic variability within this breed was observed in terms of high values of mean (±s.e.) effective number of alleles (3.3 ± 1.27), observed heterozygosity (0.5306 ± 0.22), expected Levene’s heterozygosity (0.6612 ± 0.15), expected Nei’s heterozygosity (0.6535 ± 0.14), and polymorphism information content (0.6120 ± 0.03). Low values of Wright’s fixation index, F_IS (0.2433 ± 0.05) indicated low levels of inbreeding. This basic study indicated the existence of substantial genetic diversity in the Marwari horse population. No significant genotypic linkage disequilibrium was detected across the population, suggesting no evidence of linkage between loci. A normal ‘L’ shaped distribution of mode-shift test, non-significant heterozygote excess on the basis of different models, as revealed from Sign, Standardized differences and Wilcoxon sign rank tests as well as non-significantM ratio value suggested that there was no recent bottleneck in the existing Marwari breed population, which is important information for equine breeders. This study also revealed that the Marwari breed can be differentiated from some other exotic breeds of horses on the basis of three microsatellite primers.     

Role of Motor Asymmetry and of Sex in Lateralization of Autonomic Effects

The paper presents data on the populational laterality proportions among men and women. Analysis of cardiac rhythm variations in right- and left-handed men and women in rest and during mental loading has shown a more pronounced sympathetic domination in left-handed examinees unlike right-handers. The most significant differences in the autonomic balance during mental loading were revealed between the left-handed and right-handed men. An earlier physiological maturation was established to be more characteristic of left-handed women as compared with right-handers. On the background of low and high levels of estrogens a correlation was revealed between the level of hormones and parameters of autonomic balance of the autonomic nervous system both in right-handed and left-handed women.     

The comparison of characteristics of smooth pursuit in left-handed and right-handed persons

The estimation of the smooth pursuit efficiency in healthy young adults by method based on stroboscopic stimulation is given. The influence of manual function asymmetry on smooth pursuit was tested. Subjects were classified as left-handed or right-handed under a well known handedness questionnaire of Annett supplemented by Luria's tests. It was shown that the strong right-handed persons have a high quality of smooth pursuit of stimuli moving horizontally in rightward and leftward directions with the velocities 20 degrees/s and 25 degrees/s. Left-handed persons track similar stimuli, on the average, worse than the strong right-handed ones. It haven't been observed the influence of manual function asymmetry on the dependence of the smooth pursuit efficiency from the moving stimuli direction (left to right or right to left).     

Functional asymmetry in the face.

The possible existence of one-sided dominance in the face, similar to the phenomena of handedness and footedness, has been investigated by studying smiling pattern, movements of the angles of mouth, winking, platysma contraction, raising and everting the upper lip with dilatation of the nostril, and vertical wrinkling of the forehead, on 300 right-handed and 30 left-handed persons. The conclusions are as follows: 1. The large majority of persons investigated do not use the two sides of face equally. 2. Facial ambilaterality is a rare feature. 3. There is no clear-cut correlation between handedness and the dominant side of the face. 4. The greater percentage (58.66%) of right-handed persons show a left-sided smile and find it more convenient to perform almost all exercises with the left side of the face. A still greater percentage (73.33%) of left-handed persons shows a right-sided smile and a better performance of all exercises with the right side of the face. The contralateral relationship of handedness to the dominant side of the face is significant in the right-handed and more so, in the left-handed persons.     

Winter diet composition of the golden jackal (Canis aureus L., 1758) in Serbia

The winter diet composition of golden jackals was determined by analysing the stomach contents of 248 specimens collected between December and February 2005–2009 at six localities in Serbia. The average weight of stomach contents was 189.9 ± 137.3 g. At all localities, livestock carcasses were the primary food category (frequency 56.1%, biomass 77.7%). The secondary food category consisted of small mammals taken as live prey (frequency 20.7%, biomass 5.2%). Other food categories were present less frequently (roe deer, wild boar, hare, and birds), and rarely (plant material, dogs, carnivores, lizards, and inedible inorganic material). No statistically significant differences were found in diet between jackals from different localities. The only difference was found between yearlings and adults with regard to the consumed biomass (%B). The analysis of the winter diet of golden jackals in Serbia indicates that the species has opportunistic feeding habits consisting primarily of easily accessible food sources.     

Functional MRI evaluation of supplementary motor area language dominance in right- and left-handed subjects

Functional magnetic resonance imaging (fMRI) is a non-invasive brain imaging technique widely used in the evaluation of the brain function that provides images with high temporal and spatial resolution. Investigation of the supplementary motor area (SMA) function is critical in the pre-surgical evaluation of neurological patients, since marked individual differences and complex overlapping with adjacent cortical areas exist, and it is important to spare the SMA from lesions when adjacent cortical tissue is surgically removed. We used fMRI to assess the activity of SMA in six right-handed and six left-handed healthy volunteers when a task requiring silent repetition of a series of words was given. Brain activation areas in each of the subjects were localized according to the standard Talairach coordinate space, and the individual voxels for each map were compared after 3D sagittal images were created and SMA was delimited. Quantitative analysis of hemispheric and bilateral SMA activation was described as mean ± standard deviation of hot points/total points. The results show that the language task induced bilateral SMA activation. Left SMA activation was significantly higher than right SMA activation in both right-handed and left-handed subjects.     

Comparative analysis of morphometric characters of juvenile sterlet Acipenser ruthenus L. from natural population and aquaculture

A comparative analysis was performed on sixteen morphometric characters, in three different juvenile sterlet Acipenser ruthenus L. populations. Specimens were collected from a wild population in the Serbian part of the Danube River (n = 46), from aquaculture stocks in the Czech Republic originating from Russia (n = 40), and aquaculture stocks in the Slovak Republic originating from Slovakian part of the Danube River (n = 28). Average values for total length were 29·9 ± 3·9 cm, 29·1 ± 3·7 cm and 27·3 ± 7·7 cm for Serbia, Czech Republic and Slovak Republic, respectively. Populations were compared using t‐test and sequential Bonferroni correction for multiple comparisons was applied in order to determine significant differences between them. Results of analysis showed that all three populations differed in prebarbel length, interocular distance and maximum head width. Although all these characters are head‐related, head length itself was very uniform among all populations. The natural population from the Serbian part of the Danube River differed from the populations reared in aquaculture in seven morphometric characters. The two populations reared in aquaculture consistently showed lower morphological variability than the wild population, even though they had different genetic backgrounds (Russia and Slovakia). Future genetic studies will show if this tendency is caused by a reduction in genetic variability.     

Mitochondrial DNA suggests independent evolutionary history and population decline of the Menzbir’s pipit (Anthus [gustavi] menzbieri)

In this study we use mtDNA ND2 gene (1041 bp) to evaluate the relationship between Menzbir’s (Anthus [gustavi] menzbieri) and Pechora (A. [g.] gustavi) pipits. Menzbir’s pipit is listed in the regional Red Data Book as a distinct, rare species with a small range. We obtained 18 Pechora pipit samples from two localities and 8 Menzbir’s pipit samples from a single locality. Sequences of the two taxa appear reciprocally monophyletic and are separated by 6 substitutions (0.6% divergence). Differences between the taxa explained 62.4% of the variation in our dataset. Differences among individuals within localities explained 34.8%, whereas differences between the two Pechora pipit localities explained only 2.8%. Mismatch distributions suggest that unlike the Pechora pipit localities, which either have experienced recent population growth or sustain a stable population size, the Menzbir’s pipit population may be declining. Our results suggest distinct taxonomic and conservation status for the Menzbir’s pipit.     

Diving patterns of female macaroni penguins breeding on Marion Island, South Africa

Despite the large biomass of macaroni penguins Eudyptes chrysolophus in the Southern Ocean, their feeding ecology is poorly known at some important breeding localities. We investigated the diving behaviour and diet of female macaroni penguins feeding small chicks on Marion Island (46o52′S, 37o5′E), South Africa, one of the species’ most northerly breeding sites, supporting 4% of their global population. We then compared our results with similar studies from other localities. In December 2008, we collected information on 12 foraging trips from 6 individuals using time-depth recorders, as well as diet from 42 individuals. Median trip duration was 22.8 h (5.6–80.8 h). Penguins performed 42.8 ± 15.9 dives per hour at sea, with dive depths averaging 24.6 ± 8.6 m and lasting 40.8 ± 12.1 s, although 74.3% of dives were <10 m. Euphasids dominated their diet (86% by mass), mainly Thysanoessa vicina. A second peak in dive depths at 55–80 m might reflect the 12% of fish in their diet. The substantial proportion of shallow night dives (30% of total dives) suggests some foraging occurs at night. Differences in diving patterns of individual macaroni penguins in this study confirmed the behavioural flexibility of these birds reported from other breeding localities. However, most other studies assumed that dives <3–5 m were commuting dives whereas our study suggests that at least some prey are caught during shallow dives. We highlight how different analytical methods can change the outcome of studies. Despite macaroni penguins’ apparent flexibility in foraging behaviour during the breeding season, their numbers are decreasing globally. Further investigations of their foraging behaviour are needed to assess potential competition with other predators and krill fisheries.     

Challenges using stable isotopes for estimating trophic levels in marine amphipods

In marine food web studies, stable isotopes of nitrogen (δ¹⁵N) and carbon (δ¹³C) are widely used to estimate organisms’ trophic levels (TL) and carbon sources, respectively. For smaller organisms, whole specimens are commonly analyzed. However, this “bulk method” involves several pitfalls since different tissues may fractionate stable isotopes differently. We compared the δ¹⁵N and δ¹³C values of exoskeleton versus soft tissue, in relation to whole specimens, of three common Arctic amphipods in Svalbard waters: the benthic Anonyx nugax, the sympagic (ice-associated) Gammarus wilkitzkii and the pelagic Themisto libellula. The δ¹⁵N values of the exoskeletons were significantly lower than those of the soft tissues for A. nugax (10.5 ± 0.7‰ vs. 15.7 ± 0.7‰), G. wilkitzkii (3.3 ± 0.3‰ vs. 8.3 ± 0.4‰) and T. libellula (8.6 ± 0.3‰ vs.10.8 ± 0.3‰). The differences in δ¹³C values between exoskeletons and soft tissues were insignificant, except for A. nugax (−21.2 ± 0.2‰ vs. −20.3 ± 0.2‰, respectively). The δ¹⁵N values of whole organisms were between those of the exoskeletons and the soft tissues, being similarly enriched in ¹⁵N as the exoskeletons (except G. wilkitzkii) and depleted in ¹⁵N by 1.2–3.7‰ compared to the soft tissues. The δ¹⁵N-derived TLs of the soft tissues agreed best with the known feeding preferences of the three amphipods, which suggest a potential underestimation of 0.5–1.0 TL when stable isotope analyses are performed on whole crustaceans with thick exoskeletons. The insignificant or small differences in δ¹³C values among exoskeletons, soft tissues and whole specimens, however, suggest low probability for misinterpretations of crustaceans’ primary carbon source in marine ecosystems with distinctly different δ¹³C-carbon sources.     

Variation in diet and ranging of black and white colobus monkeys in Kibale National Park,Uganda

Recently, considerable intraspecific variation in the diets and ranging behavior of colobine monkeys has been described, although in most cases this has involved documenting variation between, not within, sites. Some African colobines, such as guerezas (Colobus guereza), are relatively abundant in disturbed habitats that are very heterogeneous, raising the intriguing possibility that even groups with overlapping home ranges may exhibit large behavioral differences. If such differences occur, it will be important to understand what temporal and spatial scales adequately portray a species’ or population’s diet and ranging behavior. This study documents within-site variation in the diet and ranging behavior of guerezas in the habitat types in which they are described to be most successful—forest edge and regenerating forest. We collected data on eight groups of guerezas with overlapping home ranges for 3–5 months each in Kibale National Park, Uganda. The guerezas were highly folivorous, with leaves constituting 78.5–94.0% of the groups’ diets. The percentage of mature leaves and fruit in the diet varied widely among and within groups. We show that differences among groups in the intensity with which they fed on specific tree species were not just related to phenology, but also to differences in the forest compositions of groups’ core areas. Range size estimates varied more than fivefold among groups and the minimum distance from groups’ core areas to eucalyptus forest (which all groups regularly fed in) was a better predictor of range size than was group size. These results reveal considerable variation in the diet and ranging behavior among groups with overlapping ranges and have implications for comparative studies, investigations of within- and between-group feeding competition, and the potential for populations to adapt to anthropogenic or natural environmental change.     

Latitudinal Differences in Coconut Foliar Spiral Direction: A Re-evaluation and Hypothesis

Davis and Davis (Mathematical Modelling8: 730–733, 1987)have previously concluded, based on data collected from 42 locationsaround the world, that the ratio of right-handed to left-handedpalm trees (Cocos nuciferaL.) exhibits hemispheric differences:left-handed palms are in the majority in the Northern Hemisphere,and right-handed palms are in the majority in the Southern Hemisphere.Weighted and unweighted linear regression analyses of theirdata reveal that the skewing quotient [(left-handed—right-handed)/total]is better correlated with magnetic (dip) latitude than withgeographic or geomagnetic (centred dipole) latitude. The hypothesisis advanced that latitude-dependent biases in foliar spiraldirection may be associated with the temporally varying componentof the earth's magnetic field. It is known that changes in thecurrent strength of the ionospheric dynamo induce clockwiseearth currents in the Northern Hemisphere and counterclockwiseearth currents in the Southern Hemisphere. The hypothesis isadvanced that these earth currents, which are measurable intrees, bias the diffusion of auxin (or auxin transport proteins)in young embryos such that left-handed trees are produced preferentiallyin the Northern Hemisphere and right-handed in the SouthernHemisphere. Some tests of the Induced Current Hypothesis areproposed.Copyright 1998 Annals of Botany Company Phyllotaxis, magnetic latitude,Cocos nucifera,coconut palm, foliar spiral, auxin.     

Rigorous conformational analysis of right and left DNA helices and junction between them

On the basis of complete scanning through conformational space of dihedral angles, twelve structural genera were obtained. Subsequent energy minimization within these genera yielded a limited set of duplexes with stacking: right-handed B-form (Wilkins type), B2-form (Watson and Crick type) and left-handed Ll-form (Sasisekharan type) and the new L2-form. In the polymeric DNA only right-handed double-helices are possible, the left-handed helices are forbidden due to poor 1–5 interchain contacts. In contrast, for short fragments the left- and right-handed helicek have practically the same energies providing some physical ground for side-by-side form, which biologically is possible as recombination form and may be as replication form.     

High mangrove density enhances surface accretion, surface elevation change, and tree survival in coastal areas susceptible to sea-level rise

Survival, growth, aboveground biomass accumulation, sediment surface elevation dynamics and nitrogen accumulation in sediments were studied in experimental treatments planted with four different densities (6.96, 3.26, 1.93 and 0.95 seedlings m⁻²) of the mangrove Rhizophora mucronata in Puttalam Lagoon, Sri Lanka. Measurements were taken over a period of 1,171 days and were compared with those from unplanted controls. Trees at the lowest density showed significantly reduced survival, whilst measures of individual tree growth did not differ among treatments. Rates of surface sediment accretion (means ± SE) were 13.0 (±1.3), 10.5 (±0.9), 8.4 (±0.3), 6.9 (±0.5) and 5.7 (±0.3) mm year⁻¹ at planting densities of 6.96, 3.26, 1.93, 0.95, and 0 (unplanted control) seedlings m⁻², respectively, showing highly significant differences among treatments. Mean (±SE) rates of surface elevation change were much lower than rates of accretion at 2.8 (±0.2), 1.6 (±0.1), 1.1 (±0.2), 0.6 (±0.2) and −0.3 (±0.1) mm year⁻¹ for 6.96, 3.26, 1.93, 0.95, and 0 seedlings m⁻², respectively. All planted treatments accumulated greater nitrogen concentrations in the sediment compared to the unplanted control. Sediment %N was significantly different among densities which suggests one potential causal mechanism for the facilitatory effects observed: high densities of plants potentially contribute to the accretion of greater amounts of nutrient rich sediment. While this potential process needs further research, this study demonstrated how higher densities of mangroves enhance rates of sediment accretion and surface elevation processes that may be crucial in mangrove ecosystem adaptation to sea-level rise. There was no evidence that increasing plant density evoked a trade-off with growth and survival of the planted trees. Rather, facilitatory effects enhanced survival at high densities, suggesting that managers may be able to take advantage of high plantation densities to help mitigate sea-level rise effects by encouraging positive sediment surface elevation.