Age Differences in the Neuroelectric Adaptation to Meaningful Sounds

Much of what we know regarding the effect of stimulus repetition on neuroelectric adaptation comes from studies using artificially produced pure tones or harmonic complex sounds. Little is known about the neural processes associated with the representation of everyday sounds and how these may be affected by aging. In this study, we used real life, meaningful sounds presented at various azimuth positions and found that auditory evoked responses peaking at about 100 and 180 ms after sound onset decreased in amplitude with stimulus repetition. This neural adaptation was greater in young than in older adults and was more pronounced when the same sound was repeated at the same location. Moreover, the P2 waves showed differential patterns of domain-specific adaptation when location and identity was repeated among young adults. Background noise decreased ERP amplitudes and modulated the magnitude of repetition effects on both the N1 and P2 amplitude, and the effects were comparable in young and older adults. These findings reveal an age-related difference in the neural processes associated with adaptation to meaningful sounds, which may relate to older adults’ difficulty in ignoring task-irrelevant stimuli.     

Potential use of new diphenylurea derivatives in micropropagation of Capparis spinosa L.

A protocol for in vitro multiplication of caper (Capparis spinosa L. subsp. rupestris) from nodal segments collected from mature plants was developed. For shoot multiplication, one auxin (indol-3-butyric acid, IBA) and cytokinins of two different classes were used: the N6-substituted adenine derivatives 6-benzylamino purine (BAP), and the two synthetic phenylurea derivatives N-phenyl-N′-benzothiazol-6-ylurea (PBU) and N-phenyl-N′-(1,2,3-thidiazol-5-yl) urea (thidiazuron, TDZ). Maximum shoot production was achieved from explants cultured with the adeninic cytokinin BAP (4 μM) and the auxin IBA (0.5 μM). New shoots longer than 1 cm were used for rooting. To induce root formation, three auxins [indole-3-butyric acid (IBA), 1-naphthaleneacetic acid (NAA) and 3-Indoleacetic acid (IAA)] and two synthetic phenylurea derivatives [N,N-bis-(2,3-methylenedioxyphenyl)urea (2,3-MDPU) and N,N-bis-(3,4-methylenedioxyphenyl)urea (3,4-MDPU)] were used. All rooting compounds tested stimulated the formation of roots. However, the best result in terms of a high percentage of rooted shoots having a well-developed root system with many lateral roots was achieved with the synthetic phenylurea 2,3-MDPU (1 μM) with 93.7% of well rooted plantlets. About 80% of rooted plantlets were successfully acclimatized and transferred to the greenhouse.     

Electrophoretic and heat-stability polymorphism at the phosphoglucomutase (Pgm) locus in natural populations of Drosophila melanogaster

Genetic polymorphism for electrophoretic and heat-sensitive alleles is known at the phosphoglucomutase (Pgm) locus in Drosophila melanogaster. Analysis of the distribution of electrophoretic and thermosensitive (ts) alleles was carried out in natural populations from Canada and West Africa and compared with already known data on Italian populations [Trippa, G., Loverre, A., and Catamo, A. (1976). Nature 260:42]. The data show the existence of five common alleles, Pgm ^1.00,tr, Pgm ^1,00,ts, Pgm ^0.70,ts, Pgm ^1.20,ts, and Pgm ^1.50,tr, and two rare alleles, Pgm ^0.55,ts and Pgm ^1.20,tr. The most frequent allele is always Pgm ^1.00,tr; the second most common allele is always of the ts type. The cumulated frequencies of ts alleles in the populations varies between 11 and 32%. The heat stability polymorphism is present in all populations examined and shows again the uniform geographic pattern that has been found for electrophoretic variation at this locus.This research was partially supported by an operating grant (to G.R.C.) from the Canadian National Science and Engineering Research Council (NSERC).     

Interaction of Cd2+ with the calmodulin-activated (Ca2+ + Mg2+)-ATPase activity of human erythrocyte ghosts

Treatment of erythrocyte ghosts with micromolar concentrations of Cd2+ results in a noncompetitive inhibition of the calmodulin-dependent (Ca2+ + Mg2+)-ATPase activity. Higher concentrations of Cd2+ are required for inhibition of the (Ca2+ + Mg2+)-ATPase activity of calmodulin-depleted ghosts. The interaction of Cd2+ is time-dependent with an apparent rate constant around 0.12/min. The inhibition is relieved by addition of EGTA with a rate constant around 0.15/min. If Cd2+ is allowed to interact with calmodulin prior to the association of the protein with the ghosts, the inhibition is mainly competitive. The results suggest that the inhibitory effect caused by Cd2+ is due to an interaction with calmodulin. The slow interaction of Cd2+ suggests that calmodulin bound to the (Ca2+ + Mg2+)-ATPase is inaccessible to Cd2+.     

Bacteroides fragilis Toxin Coordinates a Pro-carcinogenic Inflammatory Cascade via Targeting of Colonic Epithelial Cells

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Opioid and Notch signaling pathways are reciprocally regulated through miR- 29a and miR-212 expression

Background

The abuse of opioids, such as morphine and phentanyl or other drugs as heroin is a social and health problem that affects an increasing number of people each year. The activation of the mu opioid receptor triggers several molecular changes that alter the expression of diverse genes, including miRNAs. The dysregulation of these molecules could explain some of the developmental alterations that are induced after drug intake. In addition, the Notch signaling cascade has also been related to alterations on these processes.

Using abundance and habitat variables to identify high conservation value areas for threatened mammals

The present study used abundance and habitat variables to design High Conservation Value Forests for wildlife protection. We considered great apes (Gorilla gorilla gorilla and Pan troglodytes troglodytes) as model species, and we used nest surveys, dietary analysis and botanical inventories to evaluate whether the traditional methods that use abundance data alone were consistent with the survival of the species. We assumed that setting a local priority area for animal conservation can be made possible if at least one variable (abundance or habitat variables) is spatially clustered and that the final decision for a species may depend on the pattern of spatial association between abundance, nesting habitat and feeding habitat. We used Kernel Density Estimation to evaluate the spatial pattern of each biological variable. The results indicate that all three variables were spatially clustered for both gorillas and chimpanzees. The abundance variables of both animal species were spatially correlated to their preferred nesting habitat variables. But while the chimpanzee feeding habitat variable was spatially correlated to the abundance and nesting habitat variables, the same pattern was not observed for gorillas. We then proposed different methods to be considered to design local priority areas for the conservation of each great ape species. Alone, the abundance variable does not successfully represent the spatial distribution of major biological requirements for the survival of wildlife species; we, therefore, recommend the integration of the spatial distribution of their food resources to overcome the mismatch caused by the existence of a biological interaction between congeneric species.     

Lung ultrasound for the diagnosis of pneumonia in children with acute bronchiolitis

Background

Guidelines currently do not recommend the routine use of chest x-ray (CXR) in bronchiolitis. However, CXR is still performed in a high percentage of cases, mainly to diagnose or rule out pneumonia. The inappropriate use of CXR results in children exposure to ionizing radiations and increased medical costs. Lung Ultrasound (LUS) has become an emerging diagnostic tool for diagnosing pneumonia in the last decades. The purpose of this study was to assess the diagnostic accuracy and reliability of LUS for the detection of pneumonia in hospitalized children with bronchiolitis and to evaluate the agreement between LUS and CXR in diagnosing pneumonia in these patients.

Methods

We enrolled children admitted to our hospital in 2016–2017 with a diagnosis of bronchiolitis and undergone CXR because of clinical suspicion of concomitant pneumonia. LUS was performed in each child by a pediatrician blinded to the patient’s clinical, laboratory and CXR findings. An exploratory analysis was done in the first 30 patients to evaluate the inter-observer agreement between a pediatrician and a radiologist who independently performed LUS. The diagnosis of pneumonia was established by an expert clinician based on the recommendations of the British Thoracic Society guidelines.

Results

Eighty seven children with bronchiolitis were investigated. A final diagnosis of concomitant pneumonia was made in 25 patients. Sensitivity and specificity of LUS for the diagnosis of pneumonia were 100% and 83.9% respectively, with an area under-the-curve of 0.92, while CXR showed a sensitivity of 96% and specificity of 87.1%. When only consolidation >?1?cm was considered consistent with pneumonia, the specificity of LUS increased to 98.4% and the sensitivity decreased to 80.0%, with an area under-the-curve of 0.89. Cohen’s kappa between pediatrician and radiologist sonologists in the first 30 patients showed an almost perfect agreement in diagnosing pneumonia by LUS (K 0.93).

Conclusions

This study shows the good accuracy of LUS in diagnosing pneumonia in children with clinical bronchiolitis. When including only consolidation size >?1?cm, specificity of LUS was higher than CXR, avoiding the need to perform CXR in these patients. Added benefit of LUS included high inter-observer agreement.

Trial registration

Identifier: NCT03280732. Registered 12 September 2017 (retrospectively registered).

     

The Association of the Nm23-M1 Protein and β-Tubulin Correlates with Cell Differentiation

The Nm23 protein is a nucleoside diphosphate kinase (NDPK) and is thought to play a critical role in metastatic behavior. It has been reported that a NDPK activity is present in microtubules assembled in vitro. Since microtubule assembly is determinant in cell growth and differentiation, we investigated whether Nm23-M1 forms molecular complexes with β-tubulin in murine cells either actively proliferating or differentiating. For this purpose a polyclonal antibody against the GST-Nm23-M1 fusion protein was generated and employed to detect Nm23-M1/β-tubulin complexes in murine tumor cells derived from the Lewis lung carcinoma (3LL) and in undifferentiated and differentiated myogenic cells (C2C12). Immunoblotting and immunoprecipitation experiments performed using the anti-fusion protein antibody demonstrated that the Nm23-M1 protein is detectable in in vitro tumor cell lines and in in vivo primary tumors but not in spontaneous lung metastases. These data are in good agreement with data previously reported. Immunoprecipitation experiments demonstrated that the Nm23-M1 protein forms complexes with β-tubulin in in vitro tumor cell lines, but not in primary tumors. Furthermore, the Nm23-M1 protein forms complexes with β-tubulin in myogenic cells prior to and after differentiation. Interestingly, however, the level of the Nm23-M1/β-tubulin complexes is remarkably increased in differentiated myotubes. In conclusion, the results indicate that the Nm23-M1 protein forms molecular complexes with β-tubulin and that the number of complexes increases during the differentiation process of murine cells.     

Single- and double-strand photocleavage of DNA by YO, YOYO and TOTO.

Photocleavage of dsDNA by the fluorescent DNA stains oxazole yellow (YO), its dimer YOYO) and the dimer TOTO of thiazole orange (TO) has been investigated as a function of binding ratio. On visible illumination, both YO and YOYO cause single-strand cleavage, with an efficiency that varies with the dye/DNA binding ratio in a manner which can be rationalized in terms of free dye being an inefficient photocleavage reagent and externally bound dye being more efficient than intercalated dye. Moreover, the photocleavage mechanism changes with binding mode. Photocleavage by externally bound dye is, at least partly, oxygen dependent with scavenger studies implicating singlet oxygen as the activated oxygen intermediate. Photocleavage by intercalated dye is essentially oxygen-independent but can be inhibited by moderate concentrations of beta- mercaptoethanol--direct attack on the phosphoribose backbone is a possible mechanism. TOTO causes single-strand cleavage approximately five times less efficiently than YOYO. No direct double-strand breaks (dsb) are detected with YO or YOYO, but in both cases single-strand breaks (ssb) are observed to accumulate to eventually produce double-strand cleavage. With intercalated YO the accumulation occurs in a manner consistent with random generation of strand lesions, while with bisintercalated YOYO the yield of double-strand cleavage (per ssb) is 5-fold higher. A contributing factor is the slow dissociation of the bis-intercalated dimer, which allows for repeated strand-attack at the same binding site, but the observation that the dsb/ssb yield is considerably lower for externally bound than for bis-intercalated YOYO at low dye/DNA ratios indicates that the binding geometry and/or the cleavage mechanism are also important for the high dsb-efficiency. In fact, double-strand cleavage yields with bis-intercalated YOYO are higher than those predicted by simple models, implying a greater than statistical probability for a second cleavage event to occur adjacent to the first (i.e. to be induced by the same YOYO molecule). With TOTO the efficiency of the ssb-accumulation is comparable to that observed with YOYO.