European river typologies fail to capture diatom, fish, and macrophyte community composition

Typology systems are frequently used in applied and fundamental ecology and are relevant for environmental monitoring and conservation. They aggregate ecosystems into discrete types based on biotic and abiotic variables, assuming that ecosystems of the same type are more alike than ecosystems of different types with regard to a specific property of interest. We evaluated whether this assumption is met by the Broad River Types (BRT), a recently proposed European river typology system, that classifies river segments based on abiotic variables, when it is used to group biological communities. We compiled data on the community composition of diatoms, fishes, and aquatic macrophytes throughout Europe and evaluated whether the composition is more similar in site groups with the same river type than in site groups of different river types using analysis of similarities, classification strength, typical species analysis, and the area under zeta diversity decline curves. We compared the performance of the BRT with those of four region-based typology systems, namely, Illies Freshwater Ecoregions, the Biogeographic Regions, the Freshwater Ecoregions of the World, and the Environmental Zones, as well as spatial autocorrelation (SA) classifications. All typology systems received low scores from most evaluation methods, relative to predefined thresholds and the SA classifications. The BRT often scored lowest of all typology systems. Within each typology system, community composition overlapped considerably between site groups defined by the types of the systems. The overlap tended to be the lowest for fishes and between Illies Freshwater Ecoregions. In conclusion, we found that existing broad-scale river typology systems fail to delineate site groups with distinct and compositionally homogeneous communities of diatoms, fishes, and macrophytes. A way to improve the fit between typology systems and biological communities might be to combine segment-based and region-based typology systems to simultaneously account for local environmental variation and historical distribution patterns, thus potentially improving the utility of broad-scale typology systems for freshwater biota.

Antiangiogenic potential of grape stem extract through inhibition of vascular endothelial growth factor expression

The aim of the present study was to investigate the antiangiogenic potential of a grape stem extract against tube formation by human endothelial cells (EA.hy926). The results showed that at low and non-cytotoxic concentrations (50 and 100 μg/ml) the grape stem extract inhibited tube formation, indicating a possible antiangiogenic activity. Moreover, the results showed that this extract inhibited the expression levels of vascular endothelial growth factor (VEGF), one of the most potent proangiogenic factors, suggesting that the tube formation inhibition by the extract may be exerted through inhibition of VEGF levels. Since it is well established that VEGF prevents apoptosis, the previous finding was further supported by the fact that the grape stem extract induced apoptosis in EA.hy926 cells. Furthermore, it was shown that the extract treatment did not change the levels of the proangiogenic molecules hypoxia inducible factor 1 alpha (HIF-1α) and cyclooxygenase-1 (COX-1). Therefore, these findings indicate that the grape stem extract reduces VEGF levels through mechanisms that may be HIF-1α- and COX-1-independent. The present study is the first showing that grape stem extracts possess antiangiogenic potential. Thus, our findings suggest that since grape stem extracts possess important bioactivities such as antiangiogenic potential, they could be exploited for developing chemopreventive and anticancer agents, while simultaneously protecting the environment through the use of a harmful waste.

Nutrition assessment of children with advanced stages of chronic kidney disease-A single center study

BACKGROUND

Malnutrition is a major problem among children with Chronic Kidney Disease (CKD) and it is essential to be recognized as early as possible. Aim of our study was to assess the nutrition status of children with CKD.

METHODS

Nutrition status of 30 children (1-16 years) with CKD stages IIIV and on peritoneal dialysis was evaluated. Malnutrition risk was assessed by Pediatric Digital Scaled MAlnutrition Risk screening Tool (PeDiSMART) score software.Anthropometry was expressed as Z-scores for age and sex. Phase angle (PhA) and body cell mass were assessed by bioelectrical impedance analysis (BIA). Three-day food intake was recorded and analyzed. Biochemical indexes were assessed.

RESULTS

Depending on the marker used for assessment 20-40% of our patients were malnourished. Intake/requirements ratio (median) was 86.5% for actual energy intake and 127% for actual protein intake. Multiple regression analysis has shown that the most determinant factor for Mid Upper Arm Circumference (MUAMC) was actual protein intake, Glomerular Filtration Rate (GFR) and age at diagnosis. PhA was mainly affected by GFR and energy intake. Statistically significant inverse correlation was found between PeDiSMART score and PhA (p=0.001), MUAMC (p=0.008) as well as protein intake (p=0.016).

CONCLUSIONS

A considerable proportion of children with advanced CKD are undernourished. Regular dietitian evaluation based on novel tools as PeDiSMART score and PhA may identify earlier patients at risk for malnutrition. Hippokratia 2014; 18 (3): 212-216.

Molecular phylogeographic analyses of the loach Oxynoemacheilus bureschi reveal post-glacial range extensions across the Balkans

Rivers on the Balkan Peninsula can be separated into ichthyofaunistic areas with different endemic fish species. The Vardar River contains a particularly large number of endemics, indicating its complete and long-term isolation from neighbouring river systems. One of the few species shared with other rivers is the loach species Oxynoemacheilus bureschi. In this study, the genetic analyses of 175 individuals of O. bureschi from 17 sites, covering the entire distribution of the species, including the Rivers Vardar (= Axios), Struma (= Strymon), Mesta (= Nestos) and Danube, were performed using one mitochondrial and one nuclear marker. Genetic differentiation among populations was in general low. Shared haplotypes were common and occurred even between distant localities and different river systems. This points to a high degree of gene flow among populations and rejects the hypothesis that the population in the Vardar River represents a relict from an early colonization of the Balkan Peninsula. In contrast, the results suggest that populations in the Vardar River, as well as those in the Danube River, are of recent origin, and a human-mediated introduction cannot be excluded. On the other hand, the populations in the Aggitis River, a left tributary of the lower Struma River, were clearly separated from the rest of the species and represent a long-term isolated lineage. Demographic analyses suggest a recent population expansion for O. bureschi, in which the population in the Aggitis River was not involved.

Making it on their own: sperm-dependent hybrid fishes (Cobitis) switch the sexual hosts and expand beyond the ranges of their original sperm donors

Interspecific hybridization may result in asexual hybrid lineages that reproduce via parthenogenesis. Contrary to true parthenogens, sperm-dependent asexuals (gynogens and hybridogens) are restricted to the range of bisexual species, generally the parental taxa, by their need for a sperm donor. It has been documented that asexual lineages may rarely use sperm from a non-parental species or even switch a host. The available literature reports do not allow distinguishing, between whether such host switches arise by the expansion of asexuals out of their parental's range (and into that of another's) or by the local extinction of a parental population followed by a host switch. The present study combines new and previously collected data on the distribution and history of gynogenetic spined loaches (Cobitis) of hybrid origin. We identified at least three clonal lineages that have independently switched their sperm dependency to different non-parental Cobitis species, and in cases incorporated their genomes. Our current knowledge of European Cobitis species and their hybrids suggests that this pattern most probably results from the expansion of gynogenetic lineages into new areas. Such expansion was independent of the original parental species. This suggests that sperm dependence is not as restrictive to geographical expansion when compared with true parthenogenesis as previously thought.

Cellular mechanisms underlying the effect of a single exposure to neonatal handling on neurotrophin-3 in the brain of 1-day-old rats

Neurotrophin-3 (NT-3) has an important role in brain development and is thus a good candidate molecule to be involved in the cellular mechanisms mediating the effects of early experiences on the brain. In the present work we employed the model of neonatal handling, which is known to affect the ability of the adult organism to respond to stressful stimuli, and determined its effects on NT-3 levels in the rat hippocampus and cortex 2, 4 and 8 h after handling on postnatal day 1. We also recorded maternal behavior during the 8 h following handling. At both the 4 and 8 h time-points there was an increase in NT-3 positive cells in field 1 of Ammon's horn (CA1 area of the hippocampus) and parietal cortex of the handled animals. In the parietal cortex NT-3 levels increased with time following handling: at 8 h there were more NT-3 positive cells than at 4 h. During the 4 h following the end of handling, handled pups were subject to more maternal licking, indicating that the more intense maternal care could underlie the handling-induced increase in NT-3. In the hippocampus, the handling induced increase in NT-3 was cancelled by inhibition of N-methyl-D-aspartate (NMDA), AMPA/kainate, or GABA-A receptors, as well as L-type voltage-gated Ca(2+) channels. It thus appears that neonatal handling activates these neurotransmitter receptors and channels, leading to increased intracellular Ca(2+) and increased NT-3 expression. NT-3 can then activate downstream effectors and exert its morphogenetic actions and thus imprint the effects of handling on the brain.

Effect of curative versus palliative surgical treatment for stage III pancreatic cancer patients

During the last decade, significant progress has been made in pancreaticoduodenectomy for patients with pancreatic carcinoma. Pancreatic resection performed by surgeons in tertiary referral centres is therefore justified, while the indications for pancreatic resection could be extended in patients with advance stages of disease. The aim of our study is to compare the effect of curative (pancreaticoduodenectomy) versus palliative surgery in patients with stage III pancreatic cancer, during a 20-years period. We retrospectively reviewed the charts of 58 consecutive patients with stage III ductal adenocarcinoma of the head of the pancreas. 23 patients underwent pancreatoduodenectomy with curative intent while the remaining 35 patients had surgery for palliative purposes (combined biliary and gastric bypass was performed in 83%). The hospital mortality rate was similar in both groups (4% vs 6%). 43% of patients undergoing pancreaticoduodenectomy had an uncomplicated post-operative course compared with 49% of patients undergoing palliative bypass. The length of surgical procedure and post-operative hospital stay in pancreaticoduodenectomy group were significant longer compared to those patients undergoing palliative bypass (p = 0.03 and p = 0.02 respectively). The overall actuarial survival was significantly (p < 0.01) longer in the group of patients who underwent pancreaticoduodenectomy compared with the group with palliative intent surgery.

CONCLUSION

Pancreaticoduodenectomy with curative intent for stage III pancreatic cancer patients, could improve prognosis with similar peri-operative morbidity and mortality when compared with palliative bypass.

What's in a name: toxicokinetics, pharmacokinetics, or just kinetics?

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The difficulties for transplant co-ordinators in finding cadaveric grafts

The increase in patients who happen to be candidates for solid organ transplantation without the proportional increase in organ donation, is a phenomenon that is observed in every centre although at different rates (1). In Greece this fact tends to take dramatic dimensions in spite of the effort that is undertaken for reducing its intensity.

Family studies in an extremely large mild haemophilia A pedigree which includes 10% of Greek haemophiliacs

We illustrate the usefulness of direct mutation detection for genetic counseling by showing its application to an extremely large mild haemophilia A pedigree (91 haemophiliacs) originating from the village of Aiani in Macedonia, northern Greece. The causative mutation has already been shown to be an A to T transversion in codon 280 of the FVIII gene which replaces Asn 280 (AAC) by Ile (ATC) and which creates a new Bam HI restriction site in exon 7. The latter permitted direct, rapid and reliable detection of the mutation in relevant family members. All major branches of the family were shown to share the mutation, and carrier status was diagnosed or excluded for 23 possible carriers. Other interesting characteristics of the Aiani haemophilic population are a slightly higher longevity and fecundity than that observed in the general population and a wide range of FVIII:C levels (5-25%) associated with the mutation.

Maximum dosage level in testing low-toxicity chemicals for carcinogenicity in rodents

Owing to the lack of sufficient theoretical and empirical information, the initial guidelines regarding animal carcinogenicity testing of chemicals adopted the most conservative approach possible. One of the recommendations was that non-toxic chemicals be tested at a level as high as 5% of the diet. Since then, a wealth of information has been accumulated, which indicates that such highly exaggerated dosage levels are not only unnecessary but produce scientifically misleading and regulatorily detrimental results that impede the development and evaluation of useful chemicals, including human drugs. This paper presents the rationale supporting the necessity of revision of the outdated maximum level of dietary exposure from 5% to 1% or 1000 mg kg-1 day-1 when the test chemical is administered in drinking water or by gavage.

Hydatid disease affecting the vertebrae

Six cases of hydatid disease affecting the vertebrae are described. Four patients presented with paraparesis and sphincter disturbances while the other two presented with low back pain and sciatica. Myelographic findings were positive in all six patients. The CT scans showed a paravertebral mass with destruction of bone in two cases. The nuclear magnetic resonance performed in one patient showed the exact extent of the disease all along the spine. Posterior laminectomy with decompression of the spinal cord and removal of the hydatid cysts was performed in all six patients. After the operation four patients received oral treatment with mebendazole. The patients with paraparesis showed little improvement of their neurological status. The two patients with low back pain and sciatica showed marked improvement. Hydatid disease affecting the vertebrae presents with neurological complications due to cord compression. The prognosis remains poor in spite of laminectomy, although removal of the hydatid cysts and long-term mebendazole medication may result in relief of symptoms.

Cervical myelopathy with ankylosing hyperostosis of the spine

We report the case of a man with ankylosing hyperostosis of the spine who developed spastic quadriparesis due to ossification of the posterior longitudinal ligament. The related literature is discussed.

Acute toxicity of micronized 8-methoxypsoralen in rodents

The acute oral and intraperitoneal LD50 values of micronized 8-Methoxypsoralen were determined in rats and mice. The values obtained in the present study were lower than those previously reported. The suggestion is made that the discrepancy in the LD50 values may possibly be attributed to differences in compound particle size in the preparations used.