Successful Treatment of Epilepsy with Serotonin Reuptake Inhibitors: Proposed Mechanism

The widely used antidepressants Specific Serotonin Reuptake Inhibitors (SSRI) have been tried with success as anticonvulsants in cases of nonsymptomatic epilepsy. This attempt was performed on the basis of experimental data suggesting the involvement of impairments of the serotonin system in the genesis of epilepsy. This overview summarizes the clinical data and presents biochemical and neurochemical evidences suggesting the mechanism of the therapeutic effects of SSRI in nonsymptomatic epilepsy. In particular, studies on blood-borne neutral amino acids and platelet serotonin transporter (SERT) in epileptics suggest: (a) That a decreased brain availability of tryptophan may be related to some types of epilepsy. (b) That reduction of the density of SERT may be a homeostatic reaction in the brain following epileptic seizures.     

Binding of Paroxetine to the Serotonin Transporter in Membranes from Different Cells,Subcellular Fractions and Species

The binding of [³H]-paroxetine to membrane serotonin transporter (SERT) has been studied in membranes from different sources and subcellular fractions. From rat were membranes from venous blood platelets, brain total cortex, brain microsomes, brain crude and purified synaptosomes. Membranes were obtained from venous blood platelets from human volunteers and from brain cortex tissue from neurosurgery (cerebral lobectomies following craniocerebral injuries). The main finding was that the K _D of paroxetine binding to the SERT was the same for platelet and nerve ending (synaptosomal) membranes. That parameter was significantly lower in membranes from brain microsomes and cortex total tissue. No species related difference was found, where comparison was possible, between human and rat tissue. The equality of K _D of paroxetine binding to blood platelet membranes and to membranes from nerve endings appears to encourage the use of such membranes as a model for brain SERT. Binding at two different temperatures for several of the fractions suggests that paroxetine–SERT interaction is entropy-driven.     

Sex differences in digestive traits in sexually size-dimorphic birds: Insights from an assimilation efficiency experiment on Black-tailed Godwit

Digestive assimilation efficiency is considered a trait with important implications for animal ecology. However, practically all studies have ignored the importance of sex differences in food assimilation efficiency (AE). Here, we investigated sex differences in dietary and physiological parameters in the Black-tailed Godwit Limosa limosa limosa feeding on rice seeds, a species with sexual dimorphism in body size and body mass. Gross daily food intake, gross energy intake, gross energy output and metabolizable energy intake did not vary significantly between sexes, but godwit females showed lower faeces energy density and higher AE than males. Mass-specific AE was similar in males and females, and the difference in AE could be attributed to the females' greater body mass. We suggest that a differential AE could play a role in explaining sex differences in habitat or micro-habitat selection during the non-breeding season in bird species with sexual dimorphism in size. Finally, we addressed the question about assimilation efficiency accuracy in models that estimate prey acquisitions by declining shorebirds as the Black-tailed Godwit.     

Archaea, Bacteria, and Algal Plastids Associated with the Reef-Building Corals Siderastrea stellata and Mussismilia hispida from Búzios, South Atlantic Ocean, Brazil

Reef-building corals may be seen as holobiont organisms, presenting diverse associated microbial communities. Best known is the symbiotic relationship with zooxanthellae, but Archaea, Bacteria, fungi, viruses, and algal plastids are also abundant. Until now, there is little information concerning microbial communities associated with Brazilian corals. The present study aims to describe the diversity of Archaea, Bacteria, and eukaryotic algal plastid communities associated with two sympatric species, Siderastrea stellata and Mussismilia hispida, from Southeastern Brazil, using 16S rRNA gene libraries. Since corals present a high number of other associated invertebrates, coral barcoding (COI) was performed to confirm the exclusive occurrence of coral DNA in our samples. Our analysis yielded 354 distinct microbial OTUs, represented mainly by novel phylotypes. Richness (Chao1 and ACE) and diversity (H') estimations of the microbial communities associated with both species were high and comparable to other studies. Rarefaction analyses showed that microbial diversity of S. stellata is higher than that of M. hispida. Libshuff comparative analyses showed that the highest microbial community similarity between the two coral species occurred in the bacterial libraries, while archaeal and plastidial communities were significantly different. Crenarchaeota dominated archaeal communities, while Proteobacteria was the most abundant bacterial phylum, dominated by alpha-Proteobacteria. Plastids were also represented by novel phylotypes and did not match with any 16S rRNA sequences of Cyanobacteria and zooxanthellae from GenBank. Our data improves the pool of available information on Brazilian coral microbes and shows corals as sources of diverse prokaryotic and picoeukaryotic communities.     

In vivo uptake of a haem analogue Zn protoporphyrin IX by the human malaria parasite P. falciparum‐infected red blood cells

The cellular traffic of haem during the development of the human malaria parasite Plasmodium falciparum, through the stages R (ring), T (trophozoite) and S (schizonts), was investigated within RBC (red blood cells). When Plasmodium cultures were incubated with a fluorescent haem analogue, ZnPPIX (Zn protoporphyrin IX) the probe was seen at the cytoplasm (R stage), and the vesicle‐like structure distribution pattern was more evident at T and S stages. The temporal sequence of ZnPPIX uptake byP. falciparum‐infected erythrocytes shows that at R and S stages, a time‐increase acquisition of the porphyrin reaches the maximum fluorescence distribution after 60 min; in contrast, at the T stage, the maximum occurs after 120 min of ZnPPIX uptake. The difference in time‐increase acquisition of the porphyrin is in agreement with a maximum activity of haem uptake at the T stage. To gain insights into haem metabolism, recombinant PfHO (P. falciparum haem oxygenase) was expressed, and the conversion of haem into BV (biliverdin) was detected. These findings point out that, in addition to haemozoin formation, the malaria parasite P. falciparum has evolved two distinct mechanisms for dealing with haem toxicity, namely, the uptake of haem into a cellular compartment where haemozoin is formed and HO activity. However, the low Plasmodium HO activity detected reveals that the enzyme appears to be a very inefficient way to scavenge the haem compared with the Plasmodium ability to uptake the haem analogue ZnPPIX and delivering it to the food vacuole.     

Uses,traditional management,perception of variation and preferences in ackee (Blighia sapida K.D. Koenig) fruit traits in Benin: implications for domestication and conservation

Background

Changing lifestyles have recently caused a severe reduction of the gathering of wild food plants. Knowledge about wild food plants and the local environment becomes lost when plants are no longer gathered. In Central Europe popular scientific publications have tried to counter this trend. However, detailed and systematic scientific investigations in distinct regions are needed to understand and preserve wild food uses. This study aims to contribute to these investigations.

Methods

Research was conducted in the hill country east of Graz, Styria, in Austria. Fifteen farmers, most using organic methods, were interviewed in two distinct field research periods between July and November 2008. Data gathering was realized through freelisting and subsequent semi-structured interviews. The culinary use value (CUV) was developed to quantify the culinary importance of plant species. Hierarchical cluster analysis was performed on gathering and use variables to identify culture-specific logical entities of plants. The study presented was conducted within the framework of the master's thesis about wild plant gathering of the first author. Solely data on gathered wild food species is presented here.

Results

Thirty-nine wild food plant and mushroom species were identified as being gathered, whereas 11 species were mentioned by at least 40 percent of the respondents. Fruits and mushrooms are listed frequently, while wild leafy vegetables are gathered rarely. Wild foods are mainly eaten boiled, fried or raw. Three main clusters of wild gathered food species were identified: leaves (used in salads and soups), mushrooms (used in diverse ways) and fruits (eaten raw, with milk (products) or as a jam).

Conclusions

Knowledge about gathering and use of some wild food species is common among farmers in the hill country east of Graz. However, most uses are known by few farmers only. The CUV facilitates the evaluation of the culinary importance of species and makes comparisons between regions and over time possible. The classification following gathering and use variables can be used to better understand how people classify the elements of their environment. The findings of this study add to discussions about food heritage, popularized by organizations like Slow Food, and bear significant potential for organic farmers.     

PTPN11 gene analysis in 74 Brazilian patients with Noonan syndrome or Noonan-like phenotype

Mutations in the PTPN11 gene are known to cause a large fraction of the cases of Noonan syndrome. The objective of this study was to determine the PTPN11 gene mutation rate in a cohort of clinically well-characterized Brazilian patients with Noonan or Noonan-like syndromes and to study the genotype-phenotype correlation. Fifty probands with Noonan syndrome ascertained according to well-established diagnostic criteria, 3 with LEOPARD syndrome, 5 with Noonan-like/multiple giant cell lesion syndrome, and 3 with neurofibromatosis/ Noonan were enrolled in this study. Mutational analysis was performed using denaturing high-performance liquid chromatography (DHPLC) followed by sequencing of amplicons with an aberrant elution profile. We detected missense mutations in the PTPN11 gene in 21 probands with Noonan syndrome (42%), in all 3 patients with LEOPARD syndrome, and in 1 case with Noonan-like/multiple giant cell lesion syndrome. One patient with neurofibromatosis-Noonan syndrome had a mutation in both the PTPN11 and NF1 genes. The only anomalies that reached statistical significance when comparing probands with and without mutations were the hematological abnormalities. Our data confirms that Noonan syndrome is a genetically heterogeneous disorder, with mutations in the PTPN11 gene responsible for roughly 50% of the cases. A definitive genotype-phenotype correlation has not been established, but the T73I mutation seems to predispose to a myeloproliferative disorder. Regarding Noonan-like syndromes, mutation of the PTPN11 gene is the main causal factor in LEOPARD syndrome, and it also plays a role in neurofibromatosis-Noonan syndrome. Noonan- like/multiple giant cell lesion syndrome, part of the spectrum of Noonan syndrome, is also heterogeneous.     

Human oocytes reversibly arrested in prophase I by phosphodiesterase type 3 inhibitor in vitro

This study addresses the role of cAMP hydrolytic isoenzyme phosphodiesterase type 3 (PDE 3) modulation on human oocyte maturation in vitro. Presence of phosphodiesterase type 3 A (PDE 3A) mRNA was confirmed in human germinal vesicle-stage (GV) oocytes. Making use of a selective PDE 3 inhibitor, Org 9935 (10 microM), oocytes retrieved from immature follicles were arrested in prophase I with a high efficiency for up to 72 h. Cumulus oocyte complexes (COCs) were retrieved in the follicular phase of the cycle before or after exposure to endogenous LH or hCG administration in vivo and randomly distributed into maturation medium with or without the PDE 3 inhibitor. Previous exposure of small follicles to LH activity in vivo had no influence on the arresting capacity of the PDE 3 inhibitor. Reversal from pharmacological arrest leads to a progression through meiosis in a normal time frame with formation of a well-aligned metaphase plate. Ultrastructure analysis of COC derived from follicles between 8 and 12 mm showed that the induced extension of prophase I arrest in vitro resulted in cytoplasm changes but not in apparent nuclear changes during culture.     

Distribution of Coenzyme Q Homologues in Brain

Ubiquinone (coenzyme Q₁₀), in addition to its function as an electron and proton carrier in mitochondrial electron transport coupled to ATP synthesis, acts in its reduced form (ubiquinol) as an antioxidant, inhibiting lipid peroxidation in biological membranes and protecting mitochondrial inner-membrane proteins and DNA against oxidative damage accompanying lipid peroxidation. Tissue ubiquinone levels are subject to regulation by physiological factors that are related to the oxidative activity of the organism: they increase under the influence of oxidative stress, e.g. physical exercise, cold adaptation, thyroid hormone treatment, and decrease during aging. In the present study, coenzyme Q homologues were separated and quantified in the brains of mice, rats, rabbits, and chickens using high-performance liquid chromatography. In addition, the coenzyme Q homologues were measured in cells such as NG-108, PC-12, rat fetal brain cells and human SHSY-5Y and monocytes. In general, Q₁ content was the lowest among the coenzyme homologues quantified in the brain. Q₉ was not detectable in the brains of chickens and rabbits, but was present in the brains of rats and mice. Q₉ was also not detected in human cell lines SHSY-5Y and monocytes. Q₁₀ was detected in the brains of mice, rats, rabbits, and chickens and in cell lines. Since both coenzyme Q and vitamin E are antioxidants, and coenzyme Q recycles vitamins E and C, vitamin E was also quantified in mice brain using HPLC-electrochemical detector (ECD). The quantity of vitamin E was lowest in the substantia nigra compared with the other brain regions. This finding is crucial in elucidating ubiquinone function in bioenergetics; in preventing free radical generation, lipid peroxidation, and apoptosis in the brain; and as a potential compound in treating various neurodegenerative disorders.