A new aminopeptidase from diamondback moth provides evidence for a gene duplication event in Lepidoptera

We screened a midgut cDNA library from diamondback moth, Plutella xylostella, with a probe generated using sequence information from an aminopeptidase N gene from Manduca sexta (MsAPN-1). The sequence recovered (PxAPN-A) encodes a protein of 988 resides with a 60% sequence identity to MsAPN-1. The two proteins share a signal peptide which directs processing by the endoplasmic reticulum, a C-terminal hydrophobic region satisfying the criterion for a GPI anchor and cleavage, and the possibility of an O-glycosylated rigid stalk attached to the GPI anchor. PxAPN-A is more closely related to MsAPN-1 than it is to another aminopeptidase recently reported from P. xylostella. Sequence comparisons with other species suggests that at least one aminopeptidase gene duplication occurred in an ancestral lepidopteran.     

Surgical resection of a virilizing adrenal mass with extensive tumor thrombus

Adrenocortical carcinoma with tumor thrombus and concomitant testosterone production is a rare entity. We describe a case of a 53-year-old woman with a testosterone producing left-sided adrenocortical carcinoma with tumor extending to the right atrium and tumor embolus to the right pulmonary artery. To our knowledge, there exist no such reported cases in the medical literature. We describe our use of techniques derived from transplant surgery for the removal of this mass. Critical components for successful resection included early renal artery ligation, hepatic mobilization off the inferior vena cava, and minimization of cardiopulmonary bypass time thus eliminating the need for deep hypothermic circulatory arrest.     

Lactococcus lactis-expressing listeriolysin O (LLO) provides protection and specific CD8(+) T cells against Listeria monocytogenes in the murine infection model

Lactococcus lactis has previously been proposed as a vaccine platform for the safe delivery of heterologous antigens. Here we utilized L. lactis as a live vector for expression of listeriolysin O (LLO), a major Listeria monocytogenes antigen and virulence factor. A variety of plasmid constructs were designed to permit either constitutive or nisin-inducible expression of secreted or non-secreted LLO in L. lactis. Recombinant strains were subsequently tested in a murine model for vaccination efficacy against L. monocytogenes infection. CD8(+) T lymphocytes specific for the LLO(91-99) epitope were detected when strains were administered via the intraperitoneal (IP) but not the oral route. Challenge with live L. monocytogenes revealed different levels of protection among the three vaccine strains tested with the nisin-inducible LLO-secreting L. lactis strain providing the greatest protection against secondary infection. This work highlights the usefulness of the GRAS (Generally Regarded As Safe) organism L. lactis as the basis of a live vaccine vector against L. monocytogenes. The work suggests that LLO-expressing L. lactis strains may also have the potential to act as a platform for directing other co-expressed antigens towards the cytosolic MHC class I pathway for enhanced stimulation of the CD8(+) T-cell response.     

Feasibility and behavioral effects of an at-home multi-night sleep restriction protocol for adolescents

Background: Sleep deprivation is common among adolescents and has been associated with adverse behavioral and educational outcomes. However, it is difficult to draw strong causal conclusions because of a dearth of experimental sleep research. In part, this appears related to methodological challenges when working with this population. This study tested the feasibility and behavioral effects of a multi‐night, at‐home experimental sleep restriction protocol in a sample of adolescents. Methods: Twenty healthy adolescents aged 13.9–16.9 years were enrolled in a three‐week sleep manipulation protocol using a counterbalanced cross‐over experimental design. The protocol included a baseline week, followed in random order by a short sleep week (Monday–Friday nights limited to 6.5 hours time in bed) and an extended sleep week (10 hours lights‐out time in bed Monday–Friday nights). Sleep was monitored via self‐report and objective actigraphy. These were reviewed with participants and parents on the Saturdays at the end of each week, when parents and participants also completed behavior rating questionnaires. Results: One participant dropped out of the study, but each of the remaining 19 displayed markedly less sleep in the short sleep condition than the extended sleep condition (average nightly gap ～2.5 hours). Data also reflected indirect effects of sleep deprivation that are consistent with an increase in homeostatic sleep drive. Compared to the extended sleep week, parents during the short sleep week reported that the participants displayed significantly greater problems with sleepiness, attention, oppositionality/irritability, behavior regulation, and metacognition. Participant self‐report results were similar, though less robust. Conclusions: A multi‐night, at‐home sleep manipulation protocol for use with adolescents is indeed feasible. This study also provided the first experimental evidence that chronic sleep restriction during adolescence is causally related to a wide range of behavioral deficits.     

An open-label, multicenter evaluation of the long-term safety and efficacy of risperidone in adolescents with schizophrenia

Background

Post-traumatic stress disorder (PTSD) is diagnosed in 20% to 53% of sexually abused children and adolescents. Living with PTSD is associated with a loss of health-related quality of life. Based on the best available evidence, the NICE Guideline for PTSD in children and adolescents recommends cognitive behavioural therapy (TF-CBT) over non-directive counselling as a more efficacious treatment.

Methods

A modelled economic evaluation conducted from the Australian mental health care system perspective estimates incremental costs and Quality Adjusted Life Years (QALYs) of TF-CBT, TF-CBT combined with selective serotonin reuptake inhibitor (SSRI), and non-directive counselling. The "no treatment" alternative is included as a comparator. The first part of the model consists of a decision tree corresponding to 12 month follow-up outcomes observed in clinical trials. The second part consists of a 30 year Markov model representing the slow process of recovery in non-respondents and the untreated population yielding estimates of long-term quality-adjusted survival and costs. Data from the 2007 Australian Mental Health Survey was used to populate the decision analytic model.

Results

In the base-case and sensitivity analyses, incremental cost-effectiveness ratios (ICERs) for all three active treatment alternatives remained less than A$7,000 per QALY gained. The base-case results indicated that non-directive counselling is dominated by TF-CBT and TF-CBT + SSRI, and that efficiency gain can be achieved by allocating more resources toward these therapies. However, this result was sensitive to variation in the clinical effectiveness parameters with non-directive counselling dominating TF-CBT and TF-CBT + SSRI under certain assumptions. The base-case results also suggest that TF-CBT + SSRI is more cost-effective than TF-CBT.

Conclusion

Even after accounting for uncertainty in parameter estimates, the results of the modelled economic evaluation demonstrated that all psychotherapy treatments for PTSD in sexually abused children have a favourable ICER relative to no treatment. The results also highlighted the loss of quality of life in children who do not receive any psychotherapy. Results of the base-case analysis suggest that TF-CBT + SSRI is more cost-effective than TF-CBT alone, however, considering the uncertainty associated with prescribing SSRIs to children and adolescents, clinicians and parents may exercise some caution in choosing this treatment alternative.     

Prediction of biogeographical ancestry from genotype: a comparison of classifiers

DNA can provide forensic intelligence regarding a donor’s biogeographical ancestry (BGA) and other externally visible characteristics (EVCs). A number of algorithms have been proposed to assign individual human genotypes to a BGA using ancestry informative marker (AIM) panels. This study compares the BGA assignment accuracy of the population clustering program STRUCTURE and three generic classification approaches including a Bayesian algorithm, genetic distance, and multinomial logistic regression (MLR). A selection of 142 ancestry informative single nucleotide polymorphisms (SNPs) were chosen from existing marker panels (SNPforID 34-plex, Eurasiaplex, Seldin, and Kidd’s AIM panels) to assess BGA classification at the continental level for Africans, Europeans, East Asians, and Amerindians. A training set of 1093 individuals with self-declared BGA from the 1000 Genomes phase 1 database was used by each classifier to predict BGA in a test set of 516 individuals from the HGDP-CEPH (Stanford) cell line panel. Tests were repeated with 0, 10, 50, 70, and 90% of the genotypes missing. Comparison of the area under the receiver operating characteristic curves (AUROCs) showed high accuracy in STRUCTURE and the generic Bayesian approach. The latter algorithm offers a computationally simpler alternative to STRUCTURE with little loss in accuracy and is suitable for phenotype prediction while STRUCTURE is not.

     

Phosphate forms an unusual tripodal complex with the Fe-Mn center of sweet potato purple acid phosphatase

Purple acid phosphatases (PAPs) are a family of binuclear metalloenzymes that catalyze the hydrolysis of phosphoric acid esters and anhydrides. A PAP in sweet potato has a unique, strongly antiferromagnetically coupled Fe(III)-Mn(II) center and is distinguished from other PAPs by its increased catalytic efficiency for a range of activated and unactivated phosphate esters, its strict requirement for Mn(II), and the presence of a mu-oxo bridge at pH 4.90. This enzyme displays maximum catalytic efficiency (k(cat)/K(m)) at pH 4.5, whereas its catalytic rate constant (k(cat)) is maximal at near-neutral pH, and, in contrast to other PAPs, its catalytic parameters are not dependent on the pK(a) of the leaving group. The crystal structure of the phosphate-bound Fe(III)-Mn(II) PAP has been determined to 2.5-A resolution (final R(free) value of 0.256). Structural comparisons of the active site of sweet potato, red kidney bean, and mammalian PAPs show several amino acid substitutions in the sweet potato enzyme that can account for its increased catalytic efficiency. The phosphate molecule binds in an unusual tripodal mode to the two metal ions, with two of the phosphate oxygen atoms binding to Fe(III) and Mn(II), a third oxygen atom bridging the two metal ions, and the fourth oxygen pointing toward the substrate binding pocket. This binding mode is unique among the known structures in this family but is reminiscent of phosphate binding to urease and of sulfate binding to lambda protein phosphatase. The structure and kinetics support the hypothesis that the bridging oxygen atom initiates hydrolysis.     

Low-density lipoprotein receptor gene (LDLR) world-wide website in familial hypercholesterolaemia: update, new features and mutation analysis

Mutations in the low density lipoprotein receptor gene (LDLR) cause familial hypercholesterolaemia (FH). The FH website (http://www.ucl. ac.uk/fh) has been updated to provide various functions enabling the analysis of the large number of LDLR mutations. To date, 683 LDLR mutations have been reported; of these 58.9% are missense mutations, 21.1% minor rearrangements, 13.5% major rearrangements and 6.6% splice site mutations. Of the 402 missense mutations, only 11.4% occurred at CpG sites. The majority of mutations were found in two functional domains, the ligand binding domain (42%) and the epidermal growth factor (EGF) precursor-like domain (47%). This report describes new features of the FH website and assesses the spectrum of mutations reported to date.