Neobetanin: isolation and identification from Beta vulgaris

A new natural plant constituent has been isolated from the root of red beet (Beta vulgaris subsp. vulgaris var. conditiva) and identified as the orange-coloured water-soluble pigment 5-O-β-D-glucopyranosylneobetanidin (neobetanin). Its structure was elucidated and characterized by ¹H and ¹³CNMR spectroscopy, FAB mass spectrometry, absorption spectroscopy, enzymatic determination of the glucose moiety, high-performance liquid chromatography and thin-layer electrophoresis. ¹H nuclear Overhauser enhancement spectra unambiguously identified the position of attachment of the sugar residue. Neobetanin was also found to occur as a minor constituent in petals of Opuntia ficusindica, Portulaca grandiflora, Zygocactus truncatus and in fruits of Phytolacca bogotensis and Rhipsalis warmingiana.     

Tissue-specific expression of a splicing mutation in the IKBKAP gene causes familial dysautonomia

Familial dysautonomia (FD; also known as "Riley-Day syndrome"), an Ashkenazi Jewish disorder, is the best known and most frequent of a group of congenital sensory neuropathies and is characterized by widespread sensory and variable autonomic dysfunction. Previously, we had mapped the FD gene, DYS, to a 0.5-cM region on chromosome 9q31 and had shown that the ethnic bias is due to a founder effect, with >99.5% of disease alleles sharing a common ancestral haplotype. To investigate the molecular basis of FD, we sequenced the minimal candidate region and cloned and characterized its five genes. One of these, IKBKAP, harbors two mutations that can cause FD. The major haplotype mutation is located in the donor splice site of intron 20. This mutation can result in skipping of exon 20 in the mRNA of patients with FD, although they continue to express varying levels of wild-type message in a tissue-specific manner. RNA isolated from lymphoblasts of patients is primarily wild-type, whereas only the deleted message is seen in RNA isolated from brain. The mutation associated with the minor haplotype in four patients is a missense (R696P) mutation in exon 19, which is predicted to disrupt a potential phosphorylation site. Our findings indicate that almost all cases of FD are caused by an unusual splice defect that displays tissue-specific expression; and they also provide the basis for rapid carrier screening in the Ashkenazi Jewish population.     

The Rhodobacter capsulatus genome

The genome of Rhodobacter capsulatus has been completely sequenced. It consists of a single chromosome containing 3.5 Mb and a circular plasmid of 134 kb. This effort, started in 1992, began with a fine-structure restriction map of an overlapping set of cosmids that covered the genome. Cosmid sequencing led to a gapped genome that was filled by primer walking on the chromosome and by using lambda clones. Methods had to be developed to handle strong stops in the high GC (68%) inserts. Annotation was done with the ERGO system at Integrated Genomics, as was the reconstruction of the cell's metabolism. It was possible to recognize 3709 orfs of which functional assignments could be made with high confidence to 2392 (65%). Unusual features include the presence of numerous cryptic phage genomes embedded in the chromosome. This revised version was published online in June 2006 with corrections to the Cover Date.     

The endosymbiotic bacterium <Emphasis Type="Italic">Wolbachia</Emphasis> enhances the nonspecific resistance to insect pathogens and alters behavior of <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

To determine biologically important effects of the cytoplasmic endosymbiont Wolbachia, two substrains of the same Drosophila melanogaster strain have been studied, one of them infected with Wolbachia and the other treated with tetracycline to eliminate the bacterium. Females of D. melanogaster infected with Wolbachia are more resistant to the fungus Blauveria bassiana (an insect pathogen) than uninfected females; infected females also exhibited changes in oviposition substrate preference. Males infected with the bacterium are more competitive than uninfected males. The possible role of Wolbachia in the formation of alternative ecological strategies of D. melanogaster is discussed.     

Activation of mGlu2/3 receptors as a new approach to treat schizophrenia: a randomized Phase 2 clinical trial

Schizophrenia is a chronic, complex and heterogeneous mental disorder, with pathological features of disrupted neuronal excitability and plasticity within limbic structures of the brain. These pathological features manifest behaviorally as positive symptoms (including hallucinations, delusions and thought disorder), negative symptoms (such as social withdrawal, apathy and emotional blunting) and other psychopathological symptoms (such as psychomotor retardation, lack of insight, poor attention and impulse control). Altered glutamate neurotransmission has for decades been linked to schizophrenia, but all commonly prescribed antipsychotics act on dopamine receptors. LY404039 is a selective agonist for metabotropic glutamate 2/3 (mGlu2/3) receptors and has shown antipsychotic potential in animal studies. With data from rodents, we provide new evidence that mGlu2/3 receptor agonists work by a distinct mechanism different from that of olanzapine. To clinically test this mechanism, an oral prodrug of LY404039 (LY2140023) was evaluated in schizophrenic patients with olanzapine as an active control in a randomized, three-armed, double-blind, placebo-controlled study. Treatment with LY2140023, like treatment with olanzapine, was safe and well-tolerated; treated patients showed statistically significant improvements in both positive and negative symptoms of schizophrenia compared to placebo (P < 0.001 at week 4). Notably, patients treated with LY2140023 did not differ from placebo-treated patients with respect to prolactin elevation, extrapyramidal symptoms or weight gain. These data suggest that mGlu2/3 receptor agonists have antipsychotic properties and may provide a new alternative for the treatment of schizophrenia.     

Dynamics of fat content during induction and termination of “trophic diapause” in Harmonia sedecimnotata Fabr. females (Coleoptera, Coccinellidae)

Experimental studies have demonstrated that onset, termination, and resumption of oviposition, same as corresponding changes in germarium size, are closely correlated with the dynamics of fat reserves. Even short-term (10 days long) termination of oviposition caused by the absence of aphid preys with the availability of carbohydrate food is accompanied by significant increase in absolute (weight) and relative (the percentage of total dry weight) fat content. This confirms the correctness of considering the studied phenomenon as a “real” reproductive diapause but not as a “short-term interruption of oviposition.” In combination with earlier published data, the results of the study once again suggest that division of insect adaptations to environmental changes into “short-term” and “long-term” adaptations based, correspondingly, on “neural” and “neurohormonal” mechanisms is rather conventional. In reality, a gradient or a spectrum of reactions is observed.     

Preliminary results on the frequency of the ΔF508 mutation in cystic fibrosis patients from the USSR

Summary The frequency of the ΔF508 mutation in a sample of 29 cystic fibrosis (CF) families from the USSR is equal to 44.8%, in agreement with previously reported haplotype data. If confirmed on a larger sample of CF patients from the USSR, this result might be indicative of the presence of a larger heterogeneity of CF mutations in the Soviet population than in other European populations.     

Carbohydrate Suppresses Parasitization and Induces Egg Retention in Trichogramma

The influence of carbohydrate (honey) on host acceptance and egg retention was studied in adult Trichogramma principium . The presence of honey reduced the percentage of ovipositing females and the mean number of eggs laid during 2 days. Consequently, in mass rearing, when Trichogramma is usually presented to factitious hosts for a short time, providing wasps with carbohydrate may decrease progeny production. The mean number of mature ovarial eggs in non-ovipositing females was much higher than in ovipositing females in both fed and starved wasps. The adaptive role of the positive correlation between food supply and egg retention in Trichogramma is discussed.