In vitro regeneration of the important North American oak species <Emphasis Type="Italic">Quercus alba</Emphasis>, <Emphasis Type="Italic">Quercus bicolor</Emphasis> and <Emphasis Type="Italic">Quercus rubra</Emphasis>

North American oak species, with their characteristic strong episodic seasonal shoot growth, are highly problematic for clonal micropropagation, resulting in the inability to achieve a stabilized shoot multiplication stage. The potential for initiating and proliferating shoot cultures derived from Quercus alba, Q. bicolor and Q. rubra explants was investigated, and a micropropagation method for these species was developed. Branch segments from 6 to 7-year-old trees were forced-flushed and the forced shoots were used as source of explants for culture initiation. A consistent shoot multiplication stage was achieved, in 13 of the 15 genotypes established in vitro, although marked differences occurred in explants from different genotypes/species. The control of efficient shoot multiplication involved the culture of decapitated shoots in a stressful horizontal position on cytokinin-containing medium with a sequence of transfers within a 6-week subculture cycle, which was beneficial to overcoming the episodic character of shoot growth. During each subculture cycle, the horizontally placed explants were cultured on media containing 0.2 mg l⁻¹ benzyladenine (BA) for 2 weeks with two successive transfers (2 weeks each) to fresh medium with 0.1 mg l⁻¹ BA, giving a 6-week subculture cycle. The general appearance and vigor of Q. alba and Q. bicolor shoot cultures were improved by the inclusion of both 0.1 mg l⁻¹ BA and 0.5 mg l⁻¹ zeatin in the medium used for the second transfer within the 6-week subculture cycle. Addition of AgNO₃ (3 mg l⁻¹) to the shoot proliferation medium of Q. rubra had a significant positive effect on shoot development pattern by reducing deleterious symptoms, including shoot tip necrosis and early senescence of leaves. The three species showed acceptable in vitro rooting rates by culturing microcuttings in medium containing 25 mg l⁻¹ indolebutyric acid for 48 h with subsequent transfer to auxin-free medium supplemented with 0.4% activated charcoal. Although an initial 5-day dark period generally improved the rooting response, it was detrimental to the quality of regenerated plantlets. However, activated charcoal stimulated not only the rooting frequencies, but it also enhanced plant quality, as evidenced by root, shoot and leaf growth.     

Identification of sex-linked SNP markers in wild populations of monomorphic birds

Single-nucleotide polymorphism (SNP) analysis is a powerful tool for population genetics, pedigree reconstruction and phenotypic trait mapping. However, the untapped potential of SNP markers to discriminate the sex of individuals in species with reduced sexual dimorphism or of individuals during immature stages remains a largely unexplored avenue. Here, we developed a novel protocol for molecular sexing of birds based on the detection of unique Z- and W-linked SNP markers. Our method is based on the identification of two unique loci, one in each sexual chromosome. Individuals are considered males when they show no calls for the W-linked SNP and are heterozygous or homozygous for the Z-linked SNP, while females exhibit both Z- and W-linked SNP calls. We validated the method in the Jackdaw (Corvus monedula). The reduced sexual dimorphism in this species makes it difficult to identify the sex of individuals in the wild. We assessed the reliability of the method using 36 individuals of known sex and found that their sex was correctly assigned in 100% of cases. The sex-linked markers also proved to be widely applicable for discriminating males and females from a sample of 927 genotyped individuals at different maturity stages, with an accuracy of 99.5%. Since SNP markers are increasingly used in quantitative genetic analyses of wild populations, the approach we propose has great potential to be integrated into broader genetic research programmes without the need for additional sexing techniques.     

Granulovirus formulations efficiently protect stored and field potatoes from Phthorimaea operculella and Tecia solanivora in Costa Rica

The control efficiency of a Phthorimaea operculella granulovirus isolate from Costa Rica (PhopGV-CR1) against the concurrent insect pests P. operculella (Zeller) and Tecia solanivora (Povolny) (Lepidoptera: Gelechiidae) was evaluated. In warehouses, the best control efficiency was achieved with a powder formulate applied inside bags, which reduced injury over 70 % compared with the untreated controls. In the field, liquid and powder virus formulations significantly reduced injury between 56.2 and 81.7 % compared with the untreated controls, and were as efficient as chemical treatments. The efficiency of formulations stored at ?20 °C for six months (liquid) or at ambient temperature for three months (powder) was maintained, but higher temperatures and/or longer exposure times resulted in loss of pathogenicity. The data presented here favor the inclusion of granulovirus formulations of PhopGV-CR1 in Integrated Pest Management programs against tuberworms in Costa Rica and give clues on storage conditions for the growers in this country.     

Caffeine-containing energy drink improves sprint performance during an international rugby sevens competition

The aim of this study was to determine the effects of a caffeine-containing energy drink on physical performance during a rugby sevens competition. A second purpose was to investigate the post-competition urinary caffeine concentration derived from the energy drink intake. On two non-consecutive days of a friendly tournament, 16 women from the Spanish National rugby sevens Team (mean age and body mass = 23 ± 2 years and 66 ± 7 kg) ingested 3 mg of caffeine per kg of body mass in the form of an energy drink (Fure^®, ProEnergetics) or the same drink without caffeine (placebo). After 60 min for caffeine absorption, participants performed a 15-s maximal jump test, a 6 × 30 m sprint test, and then played three rugby sevens games against another national team. Individual running pace and instantaneous speed during the games were assessed using global positioning satellite (GPS) devices. Urine samples were obtained pre and post-competition. In comparison to the placebo, the ingestion of the energy drink increased muscle power output during the jump series (23.5 ± 10.1 vs. 25.6 ± 11.8 kW, P = 0.05), running pace during the games (87.5 ± 8.3 vs. 95.4 ± 12.7 m/min, P < 0.05), and pace at sprint velocity (4.6 ± 3.3 vs. 6.1 ± 3.4 m/min, P < 0.05). However, the energy drink did not affect maximal running speed during the repeated sprint test (25.0 ± 1.5 vs. 25.0 ± 1.7 km/h). The ingestion of the energy drink resulted in a higher post-competition urine caffeine concentration than the placebo (3.3 ± 0.7 vs. 0.2 ± 0.1 μg/mL; P < 0.05). In summary, 3 mg/kg of caffeine in the form of a commercially available energy drink considerably enhanced physical performance during a women’s rugby sevens competition.     

Different Regional Gray Matter Loss in Recent Onset PTSD and Non PTSD after a Single Prolonged Trauma Exposure

Objective

Gray matter loss in the limbic structures was found in recent onset post traumatic stress disorder (PTSD) patients. In the present study, we measured regional gray matter volume in trauma survivors to verify the hypothesis that stress may cause different regional gray matter loss in trauma survivors with and without recent onset PTSD.

Method

High resolution T1-weighted magnetic resonance imaging (MRI) were obtained from coal mine flood disaster survivors with (n = 10) and without (n = 10) recent onset PTSD and 20 no trauma exposed normal controls. The voxel-based morphometry (VBM) method was used to measure the regional gray matter volume in three groups, the correlations of PTSD symptom severities with the gray matter volume in trauma survivors were also analyzed by multiple regression.

Results

Compared with normal controls, recent onset PTSD patients had smaller gray matter volume in left dorsal anterior cingulate cortex (ACC), and non PTSD subjects had smaller gray matter volume in the right pulvinar and left pallidum. The gray matter volume of the trauma survivors correlated negatively with CAPS scores in the right frontal lobe, left anterior and middle cingulate cortex, bilateral cuneus cortex, right middle occipital lobe, while in the recent onset PTSD, the gray matter volume correlated negatively with CAPS scores in bilateral superior medial frontal lobe and right ACC.

Conclusion

The present study identified gray matter loss in different regions in recent onset PTSD and non PTSD after a single prolonged trauma exposure. The gray matter volume of left dorsal ACC associated with the development of PTSD, while the gray matter volume of right pulvinar and left pallidum associated with the response to the severe stress. The atrophy of the frontal and limbic cortices predicts the symptom severities of the PTSD.     

Determination of plasma and tissue levels of tyramine by radioimmunoassay.

Antibodies were prepared against tyramine. The antigen was prepared as follows: p-Aminohippuric acid was coupled to mBSA using a carbodiimide reagent. The amino group was diazotized an attached to the aromatif ring of TYR. The immunogen in Freund's complete adjuvant was injected into rabbits. The specificity of the resulting antibody was determined by radioimmunoassay. Using random-labeled TYR-3H, TYR, its metabolites, phenethylamine analogs, catecholamines, and certain amino acids were evaluated by a competitive binding assay method. With this technique 4 ng of TYR inhibited the binding of TYR-3H by 50%. The radioimmunoassay of TYR was used to measure the plasma, urine, and tissue levels of TYR in rabbits. The plasma disappearance curve of TYR revealed a biphasic pattern with t1/2 of 2 min and 54 min. The highest concentration of TYR was found in adrenals and spleen. The factthat the major metabolites of TYR and a series of pharmacologically important sympathomimetics and catecholamines did not interfere, makes the radioimmunoassay of TYR a useful, simple, sensitive, and spedific method for the direct analysis of TYR in biological meterials.     

Skin aging caused by intrinsic or extrinsic processes characterized with functional proteomics

The skin provides protection against environmental stress. However, intrinsic and extrinsic aging causes significant alteration to skin structure and components, which subsequently impairs molecular characteristics and biochemical processes. Here, we have conducted an immunohistological investigation and established the proteome profiles on nude mice skin to verify the specific responses during aging caused by different factors. Our results showed that UVB‐elicited aging results in upregulation of proliferating cell nuclear antigen and strong oxidative damage in DNA, whereas chronological aging abolished epidermal cell growth and increased the expression of caspase‐14, as well as protein carbonylation. Network analysis indicated that the programmed skin aging activated the ubiquitin system and triggered obvious downregulation of 14‐3‐3 sigma, which might accelerate the loss of cell growth capacity. On the other hand, UVB stimulation enhanced inflammation and the risk of skin carcinogenesis. Collectively, functional proteomics could provide large‐scale investigation of the potent proteins and molecules that play important roles in skin subjected to both intrinsic and extrinsic aging.     

Taxonomy of Pluteus eugraptus and morphologically similar taxa

The status of the taxa morphologically similar to Pluteus eugraptus (Basidiomycota, Agaricales) was investigated with morphological and molecular (ITS region) characters. This group of species belongs in Pluteus sect. Celluloderma based on morphological and molecular characters. Two species, Pluteus multiformis, from Spain and Pluteus eludens from Madeira, Portugal, Russia and USA, are described as new. Both species share pigmented cheilocystidia and a pileipellis composed of both clavate-spheropedunculate and elongated elements with P. eugraptus, but they can be separated based on the characteristics of the cystidia and pileipellis. Pluteus multiformis is characterized by the scarce pleurocystidia, clavate cheilocystidia and caulocystidia and highly polymorphic elements of the pileipellis. Pluteus eludens is characterized mainly by utriform pleurocystidia. Pluteus eugraptus is known only with certainty from the type collection (Sri Lanka), which has been re-examined here, and it is characterized by narrowly lageniform pleurocystidia. Phylogenetic analyses based on ITS region sequence data supported the separation of P. multiformis, P. eludens and an additional collection from Japan that likely represents the true P. eugraptus.     

Effect of ACTH, dexamethasone, and adrenalectomy on the secretion of testosterone in the rat

The effect of ACTH (100 micrograms/animal/day, i.p.), dexamethasone (75 micrograms/animal/day, s.c.), both for three consecutive days, and adrenalectomy, with or without dexamethasone, maintained according to the group, one, two or three days, on the plasmatic testosterone and corticosterone levels, has been studied in adult male Wistar rats. ACTH and adrenalectomy produced a high decrease in testosterone levels (p less than 0.001 for the three days studied). Dexamethasone produced lower testosterone levels in the first day followed by partial recuperation between the second and the third days of its administration. Dexamethasone produced the effects mentioned for intact animals. The changes in corticosterone levels were according to an adequate response of the hypothalamus-pituitary-adrenal system under these experimental circumstances. ACTH exerts an inhibitory effect on testosterone secretion in the rat, so that such an effect from the data obtained after adrenalectomy and simultaneous dexamethasone injections, does not seems to be mediated either by the presence of adrenals or high corticosterone levels.     

Lantibiotic Reductase LtnJ Substrate Selectivity Assessed with a Collection of Nisin Derivatives as Substrates

Lantibiotics are potent antimicrobial peptides characterized by the presence of dehydrated amino acids, dehydroalanine and dehydrobutyrine, and (methyl)lanthionine rings. In addition to these posttranslational modifications, some lantibiotics exhibit additional modifications that usually confer increased biological activity or stability on the peptide. LtnJ is a reductase responsible for the introduction of d-alanine in the lantibiotic lacticin 3147. The conversion of l-serine into d-alanine requires dehydroalanine as the substrate, which is produced in vivo by the dehydration of serine by a lantibiotic dehydratase, i.e., LanB or LanM. In this work, we probe the substrate specificity of LtnJ using a system that combines the nisin modification machinery (dehydratase, cyclase, and transporter) and the stereospecific reductase LtnJ in Lactococcus lactis. We also describe an improvement in the production yield of this system by inserting a putative attenuator from the nisin biosynthesis gene cluster in front of the ltnJ gene. In order to clarify the sequence selectivity of LtnJ, peptides composed of truncated nisin and different mutated C-terminal tails were designed and coexpressed with LtnJ and the nisin biosynthetic machinery. In these tails, serine was flanked by diverse amino acids to determine the influence of the surrounding residues in the reaction. LtnJ successfully hydrogenated peptides when hydrophobic residues (Leu, Ile, Phe, and Ala) were flanking the intermediate dehydroalanine, while those in which dehydroalanine was flanked by one or two polar residues (Ser, Thr, Glu, Lys, and Asn) or Gly were either less prone to be modified by LtnJ or not modified at all. Moreover, our results showed that dehydrobutyrine cannot serve as a substrate for LtnJ.