Feasibility and acceptability of a whole-school social-marketing intervention to prevent unintended teenage pregnancies and promote sexual health: evidence for progression from a pilot to a phase III randomised trial in English secondary schools.

BACKGROUND: Reducing unintended teenage pregnancy and promoting adolescent sexual health remains a priority in England. Both whole-school and social-marketing interventions are promising approaches to addressing these aims. However, such interventions have not been rigorously trialled in the UK and it is unclear if they are appropriate for delivery in English secondary schools. We developed and pilot trialled Positive Choices, a new whole-school social marketing intervention to address unintended teenage pregnancy and promote sexual health. Our aim was to assess the feasibility and acceptability of the intervention and trial methods in English secondary schools against pre-defined progression criteria (relating to randomisation, survey follow-up, intervention fidelity and acceptability and linkage to birth/abortion records) prior to carrying out a phase III trial of effectiveness and cost-effectiveness. METHODS: Pilot RCT with integral process evaluation involving four intervention and two control schools in south-east England. The intervention comprised a student needs survey; a student/staff-led school health promotion council; a classroom curriculum for year-9 students (aged 13-14); whole-school student-led social-marketing activities; parent information; and a review of local and school-based sexual health services. Baseline surveys were conducted with year 8 (aged 12-13) in June 2018. Follow-up surveys were completed 12 months later. Process evaluation data included audio recording of staff training, surveys of trained staff, staff log books and researcher observations of intervention activities. Survey data from female students were linked to records of births and abortions to assess the feasibility of these constituting a phase III primary outcome. RESULTS: All six schools were successfully randomised and retained in the trial. Response rates to the survey were above 80% in both arms at both baseline and follow-up. With the exception of the parent materials, the fidelity target for implementation of essential elements in three out of four schools was achieved. Student surveys indicated 80% acceptability among those who reported awareness of the programme and interviews with staff suggested strong acceptability. Linkage to birth/abortion records was feasible although none occurred among participants. CONCLUSIONS: The criteria for progression to a phase III trial were met. Our data suggest that a whole-school social-marketing approach may be appropriate for topics that are clearly prioritised by schools. A phase III trial of this intervention is now warranted to establish effectiveness and cost-effectiveness. Births and terminations are not an appropriate primary outcome measure for such a trial. TRIAL REGISTRATION: ISRCTN65324176.

Differences in ebullitive methane release from small, shallow ponds present challenges for scaling.

Small, shallow waterbodies are potentially important sites of greenhouse gas release to the atmosphere. The role of ebullition may be enhanced here relative to larger and deeper systems, due to their shallow water, but these features remain relatively infrequently studied in comparison to larger systems. Herein, we quantify ebullitive release of methane (CH4) in small shallow ponds in three regions of North America and investigate the role of potential drivers. Shallow ponds exhibited open-water season ebullitive CH4 release rates as high as 40 mmol m-2 d-1, higher than previously reported for similar systems. Ebullitive release of CH4 varied by four orders of magnitude across our 15 study sites, with differences in flux rates both within and between regions. What is less clear are the drivers responsible for these differences. There were few relationships between open water-season ebullitive flux and physicochemical characteristics, including organic matter, temperature, and sulphate. Temperature was only weakly related to ebullitive CH4 release across the study when considering all observation intervals. Only four individual sites exhibited significant relationships between temperature and ebullitive CH4 release. Other sites were unresponsive to temperature, and region-specific factors may play a role. There is some evidence that where surface water sulphate concentrations are high, CH4 production and release may be suppressed. Missouri sites (n = 5) had characteristically low ebullitive CH4 release; here bioturbation could be important. While this work greatly expands the number of open-water season ebullition rates for small and shallow ponds, more research is needed to disentangle the role of different drivers. Further investigation of the potential thresholding behaviour of sulphate as a control on ebullitive CH4 release in lentic systems is one such opportunity. What is clear, however, is that efforts to scale emissions (e.g., as a function of temperature) must be undertaken with caution.

Resonance and dissonance asymmetry in effective physician-patient relationships.

This paper examines the proposed asymmetry that should occur between resonance and dissonance in physician-patient relationships in favour of resonance to facilitate an effective relationship. Resonance is represented by the positive emotional attractor, which comprises patients' conscious preferred future or ideal self, and dissonance is expressed by the negative emotional attractor and consists of the gaps between patients' ideal and real self or their fears, problems, and shortfalls. Intentional change theory is reviewed to optimise the physician-patient relationship. Concepts from complexity theory and recent research on emotions are used to explain positive and negative emotional attractors. The role of resonance and dissonance in physician-patient relationships is discussed along with how behaviour can be changed with positive and negative emotional attractors. This paper focuses on the quality and effectiveness of physician-patient relationships for physicians who create high versus low positive emotional attractor/negative emotional attractor ratios. Two theoretical propositions are offered and the research and practice implications are explained.

Modulation of apoptosis sensitivity through the interplay with autophagic and proteasomal degradation pathways.

Autophagic and proteasomal degradation constitute the major cellular proteolysis pathways. Their physiological and pathophysiological adaptation and perturbation modulates the relative abundance of apoptosis-transducing proteins and thereby can positively or negatively adjust cell death susceptibility. In addition to balancing protein expression amounts, components of the autophagic and proteasomal degradation machineries directly interact with and co-regulate apoptosis signal transduction. The influence of autophagic and proteasomal activity on apoptosis susceptibility is now rapidly gaining more attention as a significant modulator of cell death signalling in the context of human health and disease. Here we present a concise and critical overview of the latest knowledge on the molecular interplay between apoptosis signalling, autophagy and proteasomal protein degradation. We highlight that these three pathways constitute an intricate signalling triangle that can govern and modulate cell fate decisions between death and survival. Owing to rapid research progress in recent years, it is now possible to provide detailed insight into the mechanisms of pathway crosstalk, common signalling nodes and the role of multi-functional proteins in co-regulating both protein degradation and cell death.

Quetiapine facilitates oligodendrocyte development and prevents mice from myelin breakdown and behavioral changes.

Recent neuroimaging and postmortem studies have reported abnormalities in white matter of schizophrenic brains, suggesting the involvement of oligodendrocytes in the etiopathology of schizophrenia. This view is being supported by gene microarray studies showing the downregulation of genes related to oligodendrocyte function and myelination in schizophrenic brain compared to control subjects. However, there is currently little information available on the response of oligodendrocytes to antipsychotic drugs (APDs), which could be invaluable for corroborating the oligodendrocyte hypothesis. In this study we found: (1) quetiapine (QUE, an atypical APD) treatment in conjunction with addition of growth factors increased the proliferation of neural progenitors isolated from the cerebral cortex of embryonic rats; (2) QUE directed the differentiation of neural progenitors to oligodendrocyte lineage through extracellular signal-related kinases; (3) addition of QUE increased the synthesis of myelin basic protein and facilitated myelination in rat embryonic cortical aggregate cultures; (4) chronic administration of QUE to C57BL/6 mice prevented cortical demyelination and concomitant spatial working memory impairment induced by cuprizone, a neurotoxin. These findings suggest a new neural mechanism of antipsychotic action of QUE, and help to establish a role for oligodendrocytes in the etiopathology and treatment of schizophrenia.

Inhibition of rat liver microsomal CYP1A2 and CYP2B1 activity by N-(2-heptyl)-N-methyl-propargylamine and by N-(2-heptyl)-propargylamine.

(R)-N-(2-Heptyl)-N-methyl-propargylamine (R-2HMP) and (R)-N-(2-heptyl)-propargylamine (R-2HPA) are analogs of R-deprenyl. R-Deprenyl, a selective monoamine oxidase B inhibitor, is a mechanism-based inactivator of purified CYP2B1. The aim of the present study was to determine whether R-2HMP and R-2HPA behaved like deprenyl with respect to inhibiting cytochrome P450 (CYP450) enzyme activity. The activities of CYP1A2 and CYP1A1 were assessed by measuring the deethylation of 7-ethoxyresorufin by liver microsomes obtained from control and beta-naphthoflavone-treated female Wistar rats, respectively. CYP2B1 activity was assessed by measuring depentylation of 7-pentoxyresorufin by liver microsomes obtained from phenobarbital-treated rats. The activity of CYP1A1 was unaffected by 100 microM concentrations of R-deprenyl, R-2HMP, or R-2HPA. In contrast, the activities of CYP1A2 and CYP2B1 were significantly decreased. In general, the percentage of CYP1A2 activity remaining in the presence of 100 microM of one of these propargylamines ranged from 45 to 56%, whereas 10% or less of CYP2B1 activity remained. No marked differences between the various propargylamines were observed. The IC(50) values for the inhibition of CYP2B1 activity by R-deprenyl, R-2HMP, and R-2HPA were found to be 2.6, 8.5, and 3.6 microM, respectively. The S-enantiomers of deprenyl, 2HMP, and 2HPA also inhibited the activity of microsomal CYP2B1. R-2HMP, R-2HPA, and S-2HPA were found to be mechanism-based inactivators of CYP2B1 activity. The inactivation constants k(inact) and K(I) were found to be as follows: R-deprenyl, 1.3 microM and 0.32 min(-1); R-2HMP, 0.8 microM and 0.08 min(-1); R-2HPA, 0.5 microM and 0.36 min(-1); and S-2HPA, 0.24 microM and 0.18 min(-1).

Metabolism and pharmacokinetics, in the rat, of (R)-N-(2-Heptyl)Methyl-propargylamine (R-2HMP), a new potent monoamine oxidase inhibitor and antiapoptotic agent.

(R)-N-(2-Heptyl)-N-methylpropargylamine (R-2HMP) is a monoamine oxidase inhibitor and putative antiapoptotic agent analogous to (R)-deprenyl. In the rat, the major amine metabolites of R-2HMP have been identified as (R)-N-2-heptylmethylamine (R-2HMA), (R)-N-2-heptylpropargylamine (R-2HPA), and (R)-2-heptylamine (R-2HA). After R-2HMP was administered s.c. to male Wistar rats, it was observed that the greatest concentration was of the original drug followed in decreasing order by R-2HMA, R-2HPA, and R-2HA in brain, liver, and plasma at all times after administration. The greatest concentrations of the three metabolites were found in brain followed by liver and plasma, and the peak concentrations occurred between 15 and 30 min after administration. After oral administration, the liver contained the greatest concentrations of drug and metabolites, and, again, the peak concentrations occurred at about 15 min. In all cases, depropargylation appears to occur at a faster rate than demethylation. After s.c. administration, R-2HMP and its metabolites exhibited biexponential redistribution and elimination losses. Half-lives of the compounds in brain for the redistribution phase were: R-2HMP, 10 min; R-2HMA, 11 min; R-2HPA, 16 min; and R-2HA, 15 min.

ATP-dependent proteases controlling mitochondrial function in the yeast Saccharomyces cerevisiae.

Regulated protein degradation by ATP-dependent proteases plays a fundamental role in the biogenesis of mitochondria. Membrane-bound and soluble ATP-dependent proteases have been identified in various subcompartments of this organelle. Subunits composing these proteases are evolutionarily conserved from yeast to humans and, in support of an endosymbiotic origin of mitochondria, evolved from prokaryotic ancestors: the PIM1/Lon protease is active in the matrix of mitochondria, while the i-AAA protease and the m-AAA protease mediate the turnover of inner membrane proteins. Most of the knowledge concerning the biogenesis and the physiological role of ATP-dependent proteases comes from studies in the yeast Saccharomyces cerevisiae. Proteases were found to be required for mitochondrial stasis, for the maintenance of the morphology of the organelle and for mitochondrial genome integrity. ATP-dependent proteolysis is crucial for the expression of mitochondrially encoded subunits of respiratory chain complexes and for the assembly of these complexes. Hence, mitochondrial ATP-dependent proteases exert multiple roles which are essential for the maintenance of cellular respiratory competence.

Mcx1p, a ClpX homologue in mitochondria of Saccharomyces cerevisiae.

Members of the Hsp100/Clp-family of molecular chaperones form regulatory subunits of ATP-dependent Clp proteases and fulfill crucial roles for cellular thermotolerance. We have identified a Clp-like protein in Saccharomyces cerevisiae, Mcx1p, which shares approximately 30% sequence identity with ClpX-proteins in bacteria, plants and nematodes. Mcx1p localizes to the matrix space of mitochondria and is peripherally associated with the inner membrane. A homologue of E. coli ClpP protease was not identified when screening the yeast genome. We therefore propose that Mcx1p represents a novel molecular chaperone of mitochondria with non-proteolytic function.

The ATP-dependent PIM1 protease is required for the expression of intron-containing genes in mitochondria.

The ATP-dependent PIM1 protease, a Lon-like protease localized in the mitochondrial matrix, is required for mitochondrial genome integrity in yeast. Cells lacking PIM1 accumulate lesions in the mitochondrial DNA (mtDNA) and therefore lose respiratory competence. The identification of a multicopy suppressor, which stabilizes mtDNA in the absence of PIM1, enabled us to characterize novel functions of PIM1 protease during mitochondrial biogenesis. The synthesis of mitochondrially encoded cytochrome c oxidase subunit I (CoxI) and cytochrome b (Cob) is impaired in pim1 mutants containing mtDNA. PIM1-mediated proteolysis is required for the translation of mature COXI mRNA. Moreover, deficiencies in the splicing of COXI and COB transcripts, which appear to be restricted to introns encoding mRNA maturases, were observed in cells lacking the PIM1 gene. Transcripts of COXI and COB genes harboring multiple introns are degraded in the absence of PIM1. These results establish multiple, essential functions of the ATP-dependent PIM1 protease during mitochondrial gene expression.

Do different heparin brands influence activated clotting times?

A change in brand suppliers of heparin at our institution resulted in a number of anecdotal reports of possible differences in potency. Both products are marketed as heparin sodium extracted from porcine intestinal mucosa. Heparin Leo is 1000 international units (British Pharmacopeia) per ml. while Hepalean is 10,000 United States Pharmacopeia (U.S.P) units per ml. Perfusion records were retrospectively reviewed for one month periods when Heparin Leo (n = 52) or Hepalean (n = 61) were used to provide anticoagulation therapy for cardiopulmonary bypass. Heparin Leo was found to be less clinically potent than Hepalean. While increasing the initial loading dose of Heparin Leo by 5% (378 vs 398 units/kg-1), the initial post load activated clotting time (ACT) was 17% lower (556 vs 666 seconds). Heparin units required per kilogram per minute of cardiopulmonary bypass were 23% higher for Heparin Leo. Additionally 8 of 52 Heparin Leo patients did not achieve an initial post load ACT of greater than 400 secs while this occurred in 2 of 61 patients treated with Hepalean. These results were statistically significant. British Pharmacopeia and United States Pharmacopeia heparin reference standards differences are insufficient to explain the discrepancies observed in this study.

An 18.3 kb DNA fragment from yeast chromosome VII carries four unknown open reading frames, the gene for an Asn synthase, remnants of Ty and three tRNA genes.

An 18.3 kb DNA segment from yeast Saccharomyces cerevisiae VII encompasses the previously characterized MEP1, NUP57 and PPT1 genes as well as seven new open reading frames (ORFs) of at least 100 residues. G6358 is an ubiquitous glutamine-dependent asparagine synthase. G6362 is membrane protein highly homologous to a protein of unknown function in the yeast Schizosaccharomyces pombe. Three ORFs (G6324, G6335 and G6365) have no significant homology with previously reported proteins of characteristic motifs. G6321 and G6359, enclosed in longer ORFs, are not likely to be coding. The segment also contains tRNA genes for Asn, Arg and Ile as well as sigma element and two solo deltas. ORFs and genetic elements are named according to a preliminary working nomenclature.

Autocatalytic processing of the ATP-dependent PIM1 protease: crucial function of a pro-region for sorting to mitochondria.

The biogenesis of the ATP-dependent PIM1 protease of mitochondria was studied by mutational analysis. The ATPase and proteolytic activities of PIM1 were shown to be essential for mitochondrial function. A proteolytically inactive mutant form of PIM1 protease accumulated as a pro-form in mitochondria, revealing a two-step processing of PIM1: the matrix targeting signal is removed by the mitochondrial processing peptidase and then a pro-region of 61 amino acids is cleaved off in an autocatalytic reaction. This latter process depended on the ATP-dependent assembly of PIM1 protease subunits and can occur by an intermolecular and, most probably, also an intramolecular pathway. The respiratory competence of cells harboring mutant PIM1 protease lacking the pro-region was strongly impaired. Subcellular fractionation revealed a cytosolic localization of mutant PIM1 protease. This demonstrates the requirement for the propeptide for efficient sorting of PIM1 protease to mitochondria.

Substitution of PIM1 protease in mitochondria by Escherichia coli Lon protease.

PIM1 protease in mitochondria belongs to a conserved family of ATP-dependent proteases, which includes the Escherichia coli Lon protease. Yeast cells lacking PIM1 are largely defective in degrading misfolded proteins in the mitochondrial matrix, are respiratory deficient, and lose integrity of mitochondrial DNA. In order to analyze whether E. coli Lon protease is functionally equivalent to mitochondrial PIM1 protease, yeast cells lacking the PIM1 gene were transformed with a construct consisting of a mitochondrial targeting sequence fused onto the Lon protease. In these cells, the fusion protein was expressed and imported into mitochondria, and the targeting sequence was removed. In the absence of PIM1 protease, the E. coli Lon protease mediated the degradation of misfolded proteins in the matrix space in cooperation with the mitochondrial hsp70 system. These cells maintained the integrity of the mitochondrial genome and the respiratory function at 30 degrees C but not at 37 degrees C. Stabilization of mitochondrial DNA in Deltapim1 cells depended on protein degradation by the E. coli Lon protease, as a proteolytically inactive Lon variant was not capable of substituting for a loss of PIM1 protease. These results demonstrate functional conservation of Lon-like proteases from prokaryotes to eukaryotes and shed new light on the role of Lon-like proteases in mitochondrial biogenesis.

An 8.2 kb DNA segment from chromosome XIV carries the RPD3 and PAS8 genes as well as the Saccharomyces cerevisiae homologue of the thiamine-repressed nmt1 gene and a chromosome III-duplicated gene for a putative aryl-alcohol dehydrogenase.

A 8.2 kb DNA segment from the left arm of Saccharomyces cerevisiae chromosome XIV (GenBank/EMBL accession number: X83226) encompasses four open reading frames (ORFs) longer than 100 residues. The ORF N0295 is highly similar to the Aspergillus parasiticus and Schizosaccharomyces pombe nmt1 gene products, which are involved in thiamine biosynthesis and are strongly repressed by thiamine. N0300 is 76% identical to YCR107w, a hypothetical protein of yeast chromosome III, and 55% identical to a ligninolytic aryl-alcohol dehydrogenase from the white-rot fungus Phanerochaete chrysosporium. In addition, this fragment encodes Rpd3, a pleiotropic transcription factor (Vidal and Gaber, 1991), and part of Pas8, a protein essential for the biogenesis of peroxisomes (Voorn-Brouwer et al., 1993).

Polymorphism of a class 3 aldehyde dehydrogenase present in human saliva and in hair roots.

The types of aldehyde dehydrogenases (ALDH) present in human hair roots and in saliva were investigated. ALDH was detected by activity staining following separation of crude extracts by isoelectric focusing. Hair roots were found to express ALDH1, ALDH2, ALDH3, and ALDH4, whereas saliva expressed ALDH3. Two different patterns of ALDH3 were detected in hair roots collected from 42 donors, 40 expressed one pattern (variant I) and two another pattern (variant II) of activity staining. The variant I pattern of hair root ALDH3 changed with repetitive freezing and thawing of the sample, whereas the variant II pattern was stable. In contrast to hair root ALDH3, all patterns of ALDH3 activity in saliva were stable. The patterns of ALDH3 activity present in human hair roots that had been frozen and thawed twice matched those present in saliva collected from the same individual. Three polymorphisms of ALDH3 (variants I, II, and III) were detected in the 33 saliva samples analyzed. Variants I and II were inherited in each of three generations of a 10-member family.