The development of a 16S rRNA gene based PCR for the identification of Streptococcus pneumoniae and comparison with four other species specific PCR assays

<p>Abstract</p> <p>Background</p> <p><it>Streptococcus pneumoniae </it>is one of the most frequently encountered pathogens in humans but its differentiation from closely related but less pathogenic streptococci remains a challenge.</p> <p>Methods</p> <p>This report describes a newly-developed PCR assay (Spne-PCR), amplifying a 217 bp product of the 16S rRNA gene of <it>S. pneumoniae</it>, and its performance compared to other genotypic and phenotypic tests.</p> <p>Results</p> <p>The new PCR assay designed in this study, proved to be specific at 57°C for <it>S. pneumoniae</it>, not amplifying <it>S. pseudopneumoniae </it>or any other streptococcal strain or any strains from other upper airway pathogenic species. PCR assays (psaA, LytA, ply, spn9802-PCR) were previously described for the specific amplification of <it>S. pneumoniae</it>, but <it>psaA</it>-PCR was the only one found not to cross-react with <it>S. pseudopneumoniae</it>.</p> <p>Conclusion</p> <p>Spne-PCR, developed for this study, and psaA-PCR were the only two assays which did not mis-identify <it>S. pseudopneumoniae </it>as <it>S. pneumoniae</it>. Four other PCR assays and the AccuProbe assay were unable to distinguish between these species.</p

The Development of Criminal Style in Adolescence and Young Adulthood: Separating the Lemmings from the Loners

Despite broad consensus that most juvenile crimes are committed with peers, many questions regarding developmental and individual differences in criminal style (i.e., co-offending vs. solo offending) remain unanswered. Using prospective 3-year longitudinal data from 937 14- to 17-year-old serious male offenders, the present study investigates whether youths tend to offend alone, in groups, or a combination of the two; whether these patterns change with age; and whether youths who engage in a particular style share distinguishing characteristics. Trajectory analyses examining criminal styles over age revealed that, while most youth evinced both types of offending, two distinct groups emerged: an increasingly solo offender trajectory (83%); and a mixed style offender trajectory (17%). Alternate analyses revealed (5.5%) exclusively solo offenders (i.e., only committed solo offenses over 3 years). There were no significant differences between groups in individuals’ reported number of friends, quality of friendships, or extraversion. However, the increasingly solo and exclusively solo offenders reported more psychosocial maturity, lower rates of anxiety, fewer psychopathic traits, less gang involvement and less self reported offending than mixed style offenders. Findings suggest that increasingly and exclusively solo offenders are not loners, as they are sometimes portrayed, and that exclusively solo offending during adolescence, while rare and previously misunderstood, may not be a risk factor in and of itself

Familial Resemblance for Loneliness

Social isolation and loneliness in humans have been associated with physical and psychological morbidity, as well as mortality. This study aimed to assess the etiology of individual differences in feelings of loneliness. The genetic architecture of loneliness was explored in an extended twin-family design including 8,683 twins, siblings and parents from 3,911 families. In addition, 917 spouses of twins participated. The presence of assortative mating, genetic non-additivity, vertical cultural transmission, genotype–environment (GE) correlation and interaction was modeled. GE interaction was considered for several demographic characteristics. Results showed non-random mating for loneliness. We confirmed that loneliness is moderately heritable, with a significant contribution of non-additive genetic variation. There were no effects of vertical cultural transmission. With respect to demographic characteristics, results indicated that marriage, having offspring, more years of education, and a higher number of siblings are associated with lower levels of loneliness. Interestingly, these effects tended to be stronger for men than women. There was little evidence of changes in genetic architecture as a function of these characteristics. We conclude that the genetic architecture of loneliness points to non-additive genetic influences, suggesting it may be a trait that was not neutral to selection in our evolutionary past. Sociodemographic factors that influence the prevalence of loneliness do not affect its genetic architecture

Long-term effects of gestational protein malnutrition on postnatal growth, insulin-like growth factor (IGF)-I, and IGF-binding proteins in rat progeny.

We examined the long-term effects of dietary protein restriction during rat pregnancy on serum IGF-I, serum IGF binding proteins, and liver IGF-I gene expression during postnatal development. Pregnant Wistar rats were fed ad libitum throughout gestation a normal (20% casein diet; P20 controls) or a low (5% casein; P5) protein diet. At birth, the pups from both P20 and P5 dams were cross-fostered to well nourished lactating dams, and litters (n = 5/dietary group) were reduced in size to 6 pups. After weaning (d 22), the pups were fed the control diet ad libitum. The pups were killed at 8, 22, and 63 d of age. Gestational protein restriction caused significant growth retardation and mortality in newborn pups. Despite food rehabilitation during the suckling period (d 0-22), body weight, tail length, and the weight of liver, heart, kidney, and brain in the P5 pups remained significantly reduced at 8 and 22 d (-17 to -35%) compared with control pups. At the same time, serum and liver IGF-I concentrations in the P5 pups (on d 8: 100 +/- 9 ng/mL and 11 +/- 1 ng/g, respectively; on d 22: 340 +/- 20 ng/mL and 42 +/- 3 ng/g) were lower than in age-matched controls (on d 8: 170 +/- 12 ng/mL and 26 +/- 2 ng/g; on d 22: 470 +/- 30 ng/mL and 73 +/- 5 ng/g), although liver IGF-I mRNA abundance was not affected. After long-term food rehabilitation (d 63), tail length and organ weight recovered, and serum and liver IGF-I concentrations were normalized. However, although the P5 rats had resumed a normal growth rate, their body weight remained lower than in the controls. There were no differences in serum IGF binding proteins 1-4, insulin, and GH concentrations between the groups at any age studied. These results suggest that reduction in serum IGF-I may contribute to the reduced somatic and organ growth observed in rats after gestational protein malnutrition, and further support a role for IGF-I in the control of catch-up growth