Hierarchies of evidence applied to lifestyle Medicine (HEALM): introduction of a strength-of-evidence approach based on a methodological systematic review.

BACKGROUND: Current methods for assessing strength of evidence prioritize the contributions of randomized controlled trials (RCTs). The objective of this study was to characterize strength of evidence (SOE) tools in recent use, identify their application to lifestyle interventions for improved longevity, vitality, or successful aging, and to assess implications of the findings. METHODS: The search strategy was created in PubMed and modified as needed for four additional databases: Embase, AnthropologyPlus, PsycINFO, and Ageline, supplemented by manual searching. Systematic reviews and meta-analyses of intervention trials or observational studies relevant to lifestyle intervention were included if they used a specified SOE tool. Data was collected for each SOE tool. Conditions necessary for assigning the highest SOE grading and treatment of prospective cohort studies within each SOE rating framework were summarized. The expert panel convened to discuss the implications of findings for assessing evidence in the domain of lifestyle medicine. RESULTS AND CONCLUSIONS: A total of 15 unique tools were identified. Ten were tools developed and used by governmental agencies or other equivalent professional bodies and were applicable in a variety of settings. Of these 10, four require consistent results from RCTs of high quality to award the highest rating of evidence. Most SOE tools include prospective cohort studies only to note their secondary contribution to overall SOE as compared to RCTs. We developed a new construct, Hierarchies of Evidence Applied to Lifestyle Medicine (HEALM), to illustrate the feasibility of a tool based on the specific contributions of diverse research methods to understanding lifetime effects of health behaviors. Assessment of evidence relevant to lifestyle medicine requires a potential adaptation of SOE approaches when outcomes and/or exposures obviate exclusive or preferential reliance on RCTs. This systematic review was registered with the International Prospective Register of Systematic Reviews, PROSPERO [CRD42018082148].

Variations in the presence of chloride cells in the gills of lampreys (Petromyzontiformes) and their evolutionary implications.

Although confined to fresh water, non-parasitic species of lampreys and the landlocked parasitic sea lamprey, all of which were derived relatively recently from an adromous ancestors, still develop chloride cells, whose function in their ancestors was for osmoregulation in marine waters during the adult parasitic phase. In contrast, such cells are not developed by the non-parasitic least brook lamprey Lampetra aepyptera, which has been separated from its ancestor for >2 million years, nor by the freshwater parasitic species of the genus Ichthyomyzon. The length of time that a non-parasitic species or landlocked parasitic form or species has spent in fresh water is thus considered the overriding factor determining whether chloride cells are developed by those lampreys.

Examining new phylogenetic markers to uncover the evolutionary history of early-diverging fungi: comparing MCM7, TSR1 and rRNA genes for single- and multi-gene analyses of the Kickxellomycotina.

The recently recognised protein-coding genes MCM7 and TSR1 have shown significant promise for phylogenetic resolution within the Ascomycota and Basidiomycota, but have remained unexamined within other fungal groups (except for Mucorales). We designed and tested primers to amplify these genes across early-diverging fungal clades, with emphasis on the Kickxellomycotina, zygomycetous fungi with characteristic flared septal walls forming pores with lenticular plugs. Phylogenetic tree resolution and congruence with MCM7 and TSR1 were compared against those inferred with nuclear small (SSU) and large subunit (LSU) rRNA genes. We also combined MCM7 and TSR1 data with the rDNA data to create 3- and 4-gene trees of the Kickxellomycotina that help to resolve evolutionary relationships among and within the core clades of this subphylum. Phylogenetic inference suggests that Barbatospora, Orphella, Ramicandelaber and Spiromyces may represent unique lineages. It is suggested that these markers may be more broadly useful for phylogenetic studies among other groups of early-diverging fungi.

Orexin receptor subtype activation and locomotor behaviour in the rat.

AIM: Orexin-producing neurones, located primarily in the perifornical region of the lateral hypothalamus, project to a wide spectrum of brain sites where they influence numerous behaviours as well as modulating the neuroendocrine and autonomic responses to stress. While some of the actions of orexin appear to be mediated via the type 1 receptor, some are not, including its action on the release of one stress hormone, prolactin. We describe here the ability of orexin to increase locomotor behaviours and identify the importance of both receptor subtypes in these actions. METHODS: Rats were tested for their behavioural responses to the central activation of both the type 1 (OX(1)R) and type 2 (OX(2)R) receptor (ICV orexin A), compared to OX(2)R activation using a relatively selective OX(2)R agonist in the absence or presence of an orexin receptor antagonist that possesses highest affinity for OX(1)R. RESULTS: Increases in locomotor activity were observed, effects which were expressed by not only orexin A, which binds to both the OX(1)R and the OX(2)R receptors, but also by the relatively selective OX(2)R agonist [(Ala(11), Leu(15))-orexin B]. Furthermore, the OX(1)R selective antagonist only partially blocked the action of orexin A on most locomotor behaviours and did not block the actions of [(Ala(11), Leu(15))-orexin B]. CONCLUSION: We conclude that orexin A exerts its effects on locomotor behaviour via both the OX(1)R and OX(2)R and that agonism or antagonism of only one of these receptors for therapeutic purposes (i.e. sleep disorders) would not provide selectivity in terms of associated behavioural side effects.

Variability of platelet aggregate dispersal with glycoprotein IIb-IIIa antagonists eptifibatide and abciximab.

BACKGROUND: Utilization of glycoprotein IIb-IIIa (GPIIb-IIIa) inhibitors improves outcomes of patients with acute coronary syndromes (ACS), including those undergoing percutaneous coronary intervention (PCI). These results may be related to the ability of the inhibitors to destabilize coronary thrombi, reduce microembolization, and restore vessel patency. OBJECTIVE: To evaluate in vitro the ability of GPIIb-IIIa antagonists, abciximab and eptifibatide, to promote the disaggregation of platelet-rich thrombus. METHODS: Antagonist-induced disaggregation was assayed in plasma by aggregometry, as well as in whole blood by point of care and capillary perfusion systems. Fibrinogen dissociation from the platelet surface was quantified by flow cytometry. RESULTS: Significant disaggregation of 5 microm ADP-induced aggregates was observed after addition of either agent. The maximum extent and rate of disaggregation were significantly higher with eptifibatide than with abciximab. Both antagonists also dispersed 2 microg mL(-1) collagen-induced aggregates, again with eptifibatide having a greater effect. Eptifibatide, but not abciximab (up to 10 microg mL(-1)), was efficient at dissociating aggregates to single platelets in whole blood and dispersing aggregates that had been aged for 30 min before treatment. Eptifibatide also reduced existing thrombus burden in the perfusion model under arterial flow conditions. A key mechanism of aggregate dispersal was antagonist-induced displacement of platelet-bound fibrinogen, which was greater with eptifibatide, a competitive inhibitor of fibrinogen binding, than with the noncompetitive inhibitor, abciximab. CONCLUSIONS: These results suggest that drug concentration and residence time, along with thrombus extent and age, may be critical determinants in promoting timely recanalization.

Importance of side marking in ophthalmic surgery.

BACKGROUND: In 2003 the National Patient Safety Agency (NPSA) advised side marking for avoiding errors and reducing incorrect side surgery. This survey aimed to ascertain whether or not, these 'best practice' guidelines are currently being implemented by ophthalmic surgeons in Scotland and, if not, the reasons for this, and also to ascertain surgeons' attitudes towards marking. METHODS: Semi-structured interviews with ophthalmic surgeons throughout Scotland, either face to face or by telephone, on their current practices and attitudes relating to preventing wrong side surgery. RESULTS: Non-compliance with side marking was described by 48% of the surgeons, which includes both consultants and specialist registrars. This survey reveals incomplete implementation of this policy in ophthalmic surgery for a number of reasons. The most common was bypassing the established multi-step process of checks, which risks an increased likelihood of surgical errors. CONCLUSION: Guidelines are not consistently being implemented in their entirety by eye surgeons in Scotland. In order to improve compliance and improve patient safety, we suggest a risk-stratified approach in side marking based on individual patient factors that may encourage wider acceptance, without compromising patient safety.

Cholesterol depletion activates rapid internalization of submicron-sized acetylcholine receptor domains at the cell membrane.

Novel effects of cholesterol (Chol) on nicotinic acetylcholine receptor (AChR) cell-surface stability, internalization and function are reported. AChRs are shown to occur in the form of submicron-sized (240-280 nm) domains that remain stable at the cell-surface membrane of CHO-K1/A5 cells over a period of hours. Acute (30 min, 37 degrees C) exposure to methyl-beta-cyclodextrin (CDx), commonly used as a diagnostic tool of endocytic mechanisms, is shown here to enhance AChR internalization kinetics in the receptor-expressing clonal cell line. This treatment drastically reduced ( approximately 50%) the number of receptor domains by accelerating the rate of endocytosis (t(1/2) decreased from 1.5-0.5 h). In addition, Chol depletion produced ion channel gain-of-function of the remaining cell-surface AChR, whereas Chol enrichment had the opposite effect. Fluorescence measurements under conditions of direct excitation of the probe Laurdan and of Förster-type resonance energy transfer (FRET) using the intrinsic protein fluorescence as donor both indicated an increase in membrane fluidity in the bulk membrane and in the immediate environment of the AChR protein upon Chol depletion. Homeostatic control of Chol content at the plasmalemma may thus modulate cell-surface organization and stability of receptor domains, and fine tune receptor channel function to temporarily compensate for acute AChR loss from the cell surface.

Adolescent smoking decline during California's tobacco control programme.

OBJECTIVE: California's comprehensive tobacco control programme was 13 years old in 2002; by then, children entering adolescence at the start of the programme were young adults. This study examines whether adolescent smoking declined over this period, whether any decline carried through to young adulthood, and whether it was specific to California. SETTING AND PARTICIPANTS: Most data were from the 1990-2002 California Tobacco Surveys (CTS) (adolescents 12-17 years, > 5000/survey, young adults 18-24 years, > 1000/survey). Additional data were from the national 1992/93-2001/02 Current Population Survey (CPS) (young adults 18-24 years, > 15,000/survey). RESULTS: Over the 13 year period in California, ever puffing declined by 70% in 12-13 year olds, by 53% in 14-15 year olds from 1992-2002, and by 34% in 16-17 year olds from 1996-2002 (CTS). As noted, the decline commenced progressively later in each older group. Smoking experimentation (1+ cigarettes) and established smoking (> 100 cigarettes in lifetime) showed similar patterns. Compared to 1990, the percentage of California young adults (CTS data) who ever experimented declined by 14%, with half of the decline from 1999-2002. CPS young adult smoking prevalence (established and now smoke everyday or some days) was constant in the rest of the USA over the entire period, but California showed a recent 18% decline from 1998/99 to 2001/02. CONCLUSIONS: California's comprehensive programme may have kept new adolescent cohorts from experimenting with cigarettes. Low young adolescent experimentation rates at programme start appeared to carry through to young adulthood, resulting in a recent drop in young adult smoking prevalence in California not observed in the rest of the USA.

Radioactive waste disposal implications of extending Part IIA of the Environmental Protection Act to cover radioactively contaminated land.

A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA of the Environmental Protection Act 1990 to include radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of the radioactive wastes arising from remediation. This is expected to be principally wastes of high volume and low activity (categorised as low level waste (LLW) and very low level waste (VLLW)). The availability problem results from a lack of applications by landfill operators for authorisation to accept LLW wastes for disposal. This is apparently due to perceived adverse publicity associated with the consultation process for authorisation coupled with uncertainty over future liabilities. Disposal of waste as VLLW is limited both by questions over volumes that may be acceptable and, more fundamentally, by the likely alpha activity of wastes (originating from radium and thorium operations). Authorised on-site disposal has had little attention in policy and guidance in recent years, but may have a part to play, especially if considered commercially attractive. Disposal at BNFL's near surface disposal facility for LLW at Drigg is limited to wastes for which there are no practical alternative disposal options (and preference has been given to operational type wastes). Therefore, wastes from the radioactively contaminated land (RCL) regime are not obviously attractive for disposal to Drigg. Illustrative calculations have been performed based on possible volumes and activities of RCL arisings (and assuming Drigg's future volumetric disposal capacity is 950,000 m3). These suggest that wastes arising from implementing the RCL regime, if all disposed to Drigg, would not represent a significant fraction of the volumetric capacity of Drigg, but could have a significant impact on the radiological capacity with respect to 226Ra plus 232Th. The government's decision-making programme for managing solid radioactive wastes in the UK may possibly achieve a general consensus that the use of landfill for LLW from the RCL regime has a fundamental role to play. However, this is unlikely to change the situation within the next few years. No new national facility arising from this programme is likely to be available during the first decade of the operation of a new RCL regime. Hence it appears that Drigg will need to play an important role for some years to come.

Role of in vitro cholesterol depletion in mediating human platelet aggregation.

We investigated the direct role of cholesterol lowering on human platelet aggregation by in vitro cholesterol depletion using methyl-beta-cyclodextrin. Collagen and thrombin receptor agonist peptide induced maximal aggregation was significantly decreased in cholesterol depleted platelets. In contrast, anti-CD9 antibody, mAb7, or anti-beta(3) antibody, D3, induced percent maximal aggregation was unaffected by cholesterol depletion. Surface and total alpha(IIb)beta(3) levels were equivalent in both groups. Morphological and ultrastructural analysis of collagen induced aggregates revealed that normal and cholesterol depleted platelets changed shape and aggregated; however, cholesterol depletion impaired microtubule ring formation and aggregate size. Cholesterol depletion also diminished the extent of the open canalicular system and collagen induced platelet ATP release. These data suggest cholesterol depletion impairs platelet aggregation by altering platelet ultrastructure critical in mediating secretion. Temporal differences and differences in tyrosine phosphoprotein levels following collagen stimulation were observed, thereby indicating that platelet signaling was concurrently affected by cholesterol depletion.

Was there significant tax evasion after the 1999 50 cent per pack cigarette tax increase in California?

OBJECTIVES: Several states, including California, have implemented large cigarette excise tax increases, which may encourage smokers to purchase their cigarettes in other lower taxed states, or from other lower or non-taxed sources. Such tax evasion thwarts tobacco control objectives and may cost the state substantial tax revenues. Thus, this study investigates the extent of tax evasion in the 6-12 months after the implementation of California's 0.50 dollars/pack excise tax increase. DESIGN AND SETTING: Retrospective data analysis from the 1999 California Tobacco Surveys (CTS), a random digit dialled telephone survey of California households. MAIN OUTCOME MEASURES: Sources of cigarettes, average daily cigarette consumption, and reported price paid. RESULTS: Very few (5.1 (0.7)% (+/-95% confidence limits)) of California smokers avoided the excise tax by usually purchasing cigarettes from non- or lower taxed sources, such as out-of-state outlets, military commissaries, or the internet. The vast majority of smokers purchased their cigarettes from the most convenient and expensive sources: convenience stores/gas (petrol) stations (45.0 (1.9)%), liquor/drug stores (16.4 (1.6)%), and supermarkets (8.8 (1.2)%). CONCLUSIONS: Despite the potential savings, tax evasion by individual smokers does not appear to pose a serious threat to California's excise tax revenues or its tobacco control objectives.

Does cigarette price influence adolescent experimentation?

The economics literature generally agrees that state and federal excise taxes can play an important role in deterring adolescent smoking. Teens' apparent responsiveness to cigarette prices is puzzling, since the majority of adolescent smokers do not buy their cigarettes. Teens typically do not begin to purchase cigarettes until they have developed an established pattern of smoking. Previous studies have not had adequate measures of smoking experience to explore whether adolescents' price responsiveness may vary by smoking experience. This paper uses data from a 1993 national survey of youth smoking to explore this hypothesis.

Copepod development rates in relation to genome size and 18S rDNA copy number.

It is known that body sizes and temperature-independent developmental durations within two genera of calanoid Copepoda (Crustacea) are positively related to nuclear DNA contents of their somatic nuclei. Evidently because of the constraint of similar cell numbers among the species, (nucleotypic) effects of nucleus size on cell size and on cell-level processes are expressed at the whole-organism level. Here, we show that developmental durations of eight species of five genera are also negatively related to their greatly differing numbers of 18S rRNA genes per unit DNA. We propose that levels of rDNA iteration among copepods have been controlled by natural selection to regulate ribosome concentrations, therefore protein production and development rates, independently of the large variations in genome sizes, which are in turn adapted to regulating cell and therefore body sizes.

Active GPIIb-IIIa conformations that link ligand interaction with cytoskeletal reorganization.

Glycoprotein (GP) IIb-IIIa plays a critical role in platelet aggregation and platelet-mediated clot retraction. This study examined the intramolecular relationship between GPIIb-IIIa activation and fibrinogen binding, platelet aggregation, and platelet-mediated clot retraction. To distinguish between different high-affinity activation states of GPIIb-IIIa, the properties of an antibody (D3) specific for GPIIIa that induces GPIIb-IIIa binding to adhesive protein molecules and yet completely inhibits clot retraction were used. Clot retraction inhibition by D3 was not due to altered platelet-fibrin interaction; however, combination treatments of D3 and adenosine diphosphate (ADP) inhibited full-scale aggregation and decreased the amounts of GPIIb-IIIa and talin incorporated into the core cytoskeletons. Morphologic evaluation of the D3/ADP aggregates showed platelets that were activated but to a lesser extent when compared to ADP only. ADP addition to platelets caused an increase in the number of D3 binding sites indicating that ligand had bound to the GPIIb-IIIa receptor. These data suggest that high-affinity GPIIb-IIIa- mediated ligand binding can be separated mechanistically from GPIIb-IIIa-mediated clot retraction and that clot retraction requires additional signaling through GPIIb-IIIa after ligand binding. The conformation recognized by D3 represents the expression of a GPIIb-IIIa activation state that participates in full-scale platelet aggregation, cytoskeletal reorganization, and clot retraction.

Forskolin modulates acetylcholine receptor gating by interacting with the small extracellular loop between the M2 and M3 transmembrane domains.

1. Forskolin acts as an allosteric modulator of muscle-type nicotinic acetylcholine receptors. Receptors from mouse muscle and Torpedo electroplax demonstrate differential sensitivity to inhibition by forskolin. Previous work from this laboratory suggested that the gamma subunit is responsible for this differential sensitivity. 2. We have used a series of mouse/Torpedo species-chimeric gamma subunits to further define the site of forskolin interaction with the gamma subunit. Analysis of the patterns of forskolin inhibition of receptors containing mouse/Torpedo chimeric gamma subunits along with the mouse alpha, beta, and delta subunits suggests that forskolin interacts with the small extracellular domain that links the M2 and M3 transmembrane domains (the M2-M3 linker). 3. We suggest that the M2-M3 linker domain plays an important role in the transduction of ligand binding to the conformational changes that result in channel opening.

Association between household and workplace smoking restrictions and adolescent smoking.

CONTEXT: Recent marked increases in adolescent smoking indicate a need for new prevention approaches. Whether workplace and home smoking restrictions play a role in such prevention is unknown. OBJECTIVE: To assess the association between workplace and home smoking restrictions and adolescent smoking. DESIGN, SETTING, AND SUBJECTS: Data were analyzed from 2 large national population-based surveys, the Current Population Surveys of 1992-1993 and 1995-1996, which included 17,185 adolescents aged 15 to 17 years. MAIN OUTCOME MEASURES: Smoking status of the adolescents surveyed, compared by presence of home and workplace smoking restrictions. RESULTS: After adjusting for demographics and other smokers in the household, adolescents who lived in smoke-free households were 74% (95% confidence interval [CI], 62%-88%) as likely to be smokers as adolescents who lived in households with no smoking restrictions. Similarly, adolescents who worked in smoke-free workplaces were 68% (95% CI, 51%-90%) as likely to be smokers as adolescents who worked in a workplace with no smoking restrictions. Adolescent smokers were 1.80 (95% CI, 1.23-2.65) times more likely to be former smokers if they lived in smoke-free homes. The most marked relationship of home smoking restrictions to current adolescent smoking occurred in households where all other members were never-smokers. Current smoking prevalence among adolescents in homes without smoking restrictions approached that among adolescents in homes with a current smoker but with smoking restrictions. CONCLUSIONS: Parents with minor children should be encouraged to adopt smoke-free homes. Smoke-free workplaces can also augment smoking prevention. These findings emphasize the importance of tobacco control strategies aimed at the entire population rather than at youth alone. JAMA. 2000;284:717-722

Chronic hypoxia, pregnancy, and endothelium-mediated relaxation in guinea pig uterine and thoracic arteries.

Vasodilation that occurs during normal pregnancy is associated with enhanced relaxation and decreased contractile response to agonists, which are in part due to increased stimulated and basal nitric oxide (NO). In preeclampsia and/or pregnancies carried at high altitude (HA), this normal vascular adjustment is reversed or diminished. We previously reported that HA exposure did not inhibit the pregnancy-associated decrease in contractile response to agonist or basal NO in guinea pig uterine arteries (UA). We therefore sought to determine whether altitude interfered with effects of pregnancy on endothelium-dependent relaxation through a reduction in stimulated NO. We examined the relaxation response to ACh in UA and bradykinin in thoracic arteries (TA) and effects of NO inhibition with 200 microM N(G)-nitro-L-arginine (L-NNA) in arterial rings isolated from nonpregnant and pregnant guinea pigs exposed throughout gestation to low altitude (LA, 1,600 m, n = 26) or HA (3,962 m, n = 22). In pregnant UA, relaxation to ACh was enhanced (P < 0.05) at both altitudes and NO inhibition diminished, but did not reverse, ACh relaxation. The effect of L-NNA on the relaxation response to ACh was less in HA than in LA animals (P = 0.0021). In nonpregnant UA, relaxation to ACh was similar in LA and HA animals. L-NNA reversed the relaxation response to ACh at HA but not at LA. In TA, relaxation to bradykinin was unaltered by pregnancy or altitude and was completely reversed by NO inhibition. These data suggest that effects of NO inhibition are diminished in UA during pregnancy at HA. Additional studies are needed to confirm whether these effects are mediated through inhibition of stimulated NO. HA exposure did not inhibit relaxation to ACh, perhaps because of stimulation of other vasodilators.

Acetylcholine receptor gating is influenced by the polarity of amino acids at position 9' in the M2 domain.

Ligand-gated ion channels contain a conserved leucine at position 9' (L9') in the M2 transmembrane domain. We used multiple substitutions at this position in the gamma subunit of the mouse acetylcholine receptor (AChR) (gammaL9') to examine the role of residue polarity at this position in the gating process at both the macroscopic and single-channel levels. The midpoint of the macroscopic dose-response relationship (EC(50)) and the channel closing rate constant, alpha, decreased as the polarity of the residue at that position increased, suggesting a stabilization of the open state of the channel. Both parameters showed similar dependencies on the polarity of the substituted residue. These data support the notion that during AChR gating, the amino acid at the 9' position moves into a polar environment, and that interactions between this residue and the polar environment determine the stability of the open state. Since this residue is conserved in all other members of the ligand-gated ion channel family, we suggest that a similar mechanism applies to the other members of the family.