Novel Phialophora species from leaf-cutting ants (tribe Attini)

Ants in the tribe Attini (Hymenoptera, Formicidae) maintain a 50 million-year-old lifestyle of co-evolution with symbiotic basidiomycetous fungi which they cultivate as essential source of nutrition. However, other microorganisms have been reported from ant habitats indicating a higher diversity of consistently associated species than established to date. Recently, black yeast-like fungi have been reported as a possible symbiont, like a competitor of the actinomycete bacteria that grow in the integument of the insects. During the mating season, gynes of Atta capiguara and A. laevigata were collected from nests located in Botucatu, SP, Brazil and sampled using flotation technique. Phylogenetic analysis based on ITS, partial 28S (LSU) and β-tubulin sequences revealed the occurrence of two novel species of Phialophora among the melanized fungi isolated.     

A comparison of neural correlates underlying social cognition in Klinefelter syndrome and autism

Klinefelter syndrome (KS) is a genetic syndrome characterized by the presence of an extra X chromosome that appears to increase the risk of psychopathology, such as autism symptoms. This study used functional magnetic resonance imaging to determine underlying mechanisms related to this risk, with the aim of gaining insight into neural mechanisms behind social-cognitive dysfunction in KS and autism, and understanding similarities and differences in social information processing deficits. Fourteen boys with KS, seventeen boys with autism spectrum disorders (ASD) and nineteen non-clinical male controls aged 10–18 years were scanned while matching and labeling facial expressions (i.e. face processing and affect labeling, respectively). No group differences in neural activation were found during face processing. However, during affect labeling, the ASD group showed increased activation in the amygdala compared with controls, while the KS group showed increased activation in frontal areas compared with both controls and the ASD group. No group differences in task performance were found. Although behavioral symptoms of social dysfunction appear similar both in boys with KS and ASD, this is the first study to demonstrate different underlying etiologies. These results may aid in identifying different pathways to autism symptoms, which may help understanding variability within the ASD spectrum.     

Low resting metabolic rate is associated with greater lifespan because of a confounding effect of body fatness

A negative association between resting metabolic rate (RMR) and lifespan is the cornerstone of the rate of living and free-radical damage theories of aging. Empirical studies supporting a negative association of RMR to lifespan may arise from the correlation between RMR and both daily energy expenditure (DEE) and thermoregulatory activity energy expenditure (TAEE). We screened 540 female mice for higher and lower DEE and measured RMR in the resulting 324 (60 %). We then selected 92 mice in which there was no link between residual from the regression of RMR against body mass (BM) and residual of DEE against BM to separate the effects of these traits. Lifespan was not significantly related to body mass, DEE and TAEE, but significantly negatively related to RMR. Fat-free mass (FFM) and fat mass (FM) were both significantly positively related to RMR. After removing the effect of FFM on RMR, the association between RMR and lifespan remained significantly negative; however, after statistically removing the effect of FM on RMR, the significant association between RMR and lifespan disappeared. We conclude that the negative association between RMR and lifespan is primarily due to the effect of FM, with FM positively related to both RMR and mortality and hence RMR negatively to lifespan. In 40 additional screened mice, greater FM was also associated with greater oxidative damage to DNA.     

Ventilatory support and predictors of hospital stay in neonates

: Ventilatory support in neonatal intensive care units (NICU) and related care modalities have profound lifelong benefits for neonates. : Ventilatory support and predictors of hospital stay were prospectively examined in 262 neonates and their mothers who were admitted to a NICU. A mixed-model, generalized estimating equation approach was used for prediction analysis, accounting for the dependencies of multiple births (26.3% of sample). : Predictors for hospital stay included gestational age, congenital defects, birth weight, days requiring ventilator support, and oxygen support. Cubic curves present the best-fit model for the relationships between maturity (gestational age and birth weight) and length of hospital stay; along with days requiring oxygen support, ventilator support, and central arterial and venous access lines. : Ventilatory support and associated care modalities are important resources for high-risk neonates during hospital stay. Future studies need to determine the best care course for neonatal ventilatory support to prevent complications.