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1.
J Insect Sci ; 24(3)2024 May 01.
Article in English | MEDLINE | ID: mdl-38913610

ABSTRACT

Bactrocera tryoni (Froggatt) and Bactrocera neohumeralis (Hardy) are sibling fruit fly species that are sympatric over much of their ranges. Premating isolation of these close relatives is thought to be maintained in part by allochrony-mating activity in B. tryoni peaks at dusk, whereas in B. neohumeralis, it peaks earlier in the day. To ascertain whether differences in pheromone composition may also contribute to premating isolation between them, this study used solid-phase microextraction and gas chromatography-mass spectrometry to characterize the rectal gland volatiles of a recently collected and a more domesticated strain of each species. These glands are typical production sites and reservoirs of pheromones in bactrocerans. A total of 120 peaks were detected and 50 were identified. Differences were found in the composition of the rectal gland emissions between the sexes, species, and recently collected versus domesticated strains of each species. The compositional variation included several presence/absence and many quantitative differences. Species and strain differences in males included several relatively small alcohols, esters, and aliphatic amides. Species and strain differences in females also included some of the amides but additionally involved many fatty acid esters and 3 spiroacetals. While the strain differences indicate there is also heritable variation in rectal gland emissions within each species, the species differences imply that compositional differences in pheromones emitted from rectal glands could contribute to the premating isolation between B. tryoni and B. neohumeralis. The changes during domestication could also have significant implications for the efficacy of Sterile Insect Technique control programs.


Subject(s)
Pheromones , Tephritidae , Animals , Male , Female , Tephritidae/genetics , Tephritidae/physiology , Tephritidae/metabolism , Sympatry , Gas Chromatography-Mass Spectrometry , Species Specificity , Reproductive Isolation , Sexual Behavior, Animal , Solid Phase Microextraction
2.
Appl Environ Microbiol ; 86(10)2020 05 05.
Article in English | MEDLINE | ID: mdl-32198167

ABSTRACT

Burkholderia sp. strain SG-MS1 and Pseudomonas sp. strain SG-MS2 have previously been found to mineralize (+)-pinoresinol through a common catabolic pathway. Here, we used comparative genomics, proteomics, protein semipurification, and heterologous expression to identify a flavoprotein from the vanillyl alcohol oxidase/p-cresol methyl hydroxylase (VAO/PCMH) enzyme family in SG-MS2 that carries out the initial hydroxylation of (+)-pinoresinol at the benzylic carbon. The cognate gene is translationally coupled with a downstream cytochrome gene, and the cytochrome is required for activity. The flavoprotein has a unique combination of cofactor binding and cytochrome requirements for the VAO/PCMH family. The heterologously expressed enzyme has a Km of 1.17 µM for (+)-pinoresinol. The enzyme is overexpressed in strain SG-MS2 upon exposure to (+)-pinoresinol, along with 45 other proteins, 22 of which were found to be encoded by genes in an approximately 35.1-kb cluster also containing the flavoprotein and cytochrome genes. Homologs of 18 of these 22 genes, plus the flavoprotein and cytochrome genes, were also found in a 38.7-kb cluster in SG-MS1. The amino acid identities of four of the other proteins within the SG-MS2 cluster suggest they catalyze conversion of hydroxylated pinoresinol to protocatechuate and 2-methoxyhydroquinone. Nine other proteins upregulated in SG-MS2 on exposure to (+)-pinoresinol appear to be homologs of proteins known to comprise the protocatechuate and 2-methoxyhydroquinone catabolic pathways, but only three of the cognate genes lie within the cluster containing the flavoprotein and cytochrome genes.IMPORTANCE (+)-Pinoresinol is an important plant defense compound, a major food lignan for humans and some other animals, and the model compound used to study degradation of the ß-ß' linkages in lignin. We report a gene cluster, in one strain each of Pseudomonas and Burkholderia, that is involved in the oxidative catabolism of (+)-pinoresinol. The flavoprotein component of the α-hydroxylase which heads the pathway belongs to the 4-phenol oxidizing (4PO) subgroup of the vanillyl alcohol oxidase/p-cresol methyl hydroxylase (VAO/PCMH) enzyme family but constitutes a novel combination of cofactor and electron acceptor properties for the family. It is translationally coupled with a cytochrome gene whose product is also required for activity. The work casts new light on the biology of (+)-pinoresinol and its transformation to other bioactive molecules. Potential applications of the findings include new options for deconstructing lignin into useful chemicals and the generation of new phytoestrogenic enterolactones from lignans.


Subject(s)
Bacterial Proteins/genetics , Flavoproteins/genetics , Furans/metabolism , Genes, Bacterial/genetics , Lignans/metabolism , Pseudomonas/genetics , Bacterial Proteins/metabolism , Flavoproteins/metabolism , Metabolic Networks and Pathways , Multigene Family , Oxidation-Reduction , Pseudomonas/metabolism
3.
J Chem Ecol ; 46(5-6): 475-482, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32529331

ABSTRACT

Trail-following behavior is a key to ecological success of termites, allowing them to orient themselves between the nesting and foraging sites. This behavior is controlled by specific trail-following pheromones produced by the abdominal sternal gland occurring in all termite species and developmental stages. Trail-following communication has been studied in a broad spectrum of species, but the "higher" termites (i.e. Termitidae) from the subfamily Syntermitinae remain surprisingly neglected. To fill this gap, we studied the trail-following pheromone in six genera and nine species of Syntermitinae. Our chemical and behavioral experiments showed that (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol is the single component of the pheromone of all the termite species studied, except for Silvestritermes euamignathus. This species produces both (3Z,6Z)-dodeca-3,6-dien-1-ol and neocembrene, but only (3Z,6Z)-dodeca-3,6-dien-1-ol elicits trail-following behavior. Our results indicate the importance of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol, the most widespread communication compound in termites, but also the repeated switches to other common pheromones as exemplified by S. euamignathus.


Subject(s)
Isoptera/physiology , Pheromones/metabolism , Animals
4.
Appl Environ Microbiol ; 84(4)2018 02 15.
Article in English | MEDLINE | ID: mdl-29222099

ABSTRACT

Pinoresinol is a dimer of two ß-ß'-linked coniferyl alcohol molecules. It is both a plant defense molecule synthesized through the shikimic acid pathway and a representative of several ß-ß-linked dimers produced during the microbial degradation of lignin in dead plant material. Until now, little has been known about the bacterial catabolism of such dimers. Here we report the isolation of the efficient (+)-pinoresinol-mineralizing Pseudomonas sp. strain SG-MS2 and its catabolic pathway. Degradation of pinoresinol in this strain is inducible and proceeds via a novel oxidative route, which is in contrast to the previously reported reductive transformation by other bacteria. Based on enzyme assays and bacterial growth, cell suspension, and resting cell studies, we provide conclusive evidence that pinoresinol degradation in strain SG-MS2 is initiated by benzylic hydroxylation, generating a hemiketal via a quinone methide intermediate, which is then hydrated at the benzylic carbon by water. The hemiketal, which stays in equilibrium with the corresponding keto alcohol, undergoes an aryl-alkyl cleavage to generate a lactone and 2-methoxyhydroquinone. While the fate of 2-methoxyhydroquinone is not investigated further, it is assumed to be assimilated by ring cleavage. The lactone is further metabolized via two routes, namely, lactone ring cleavage and benzylic hydroxylation via a quinone methide intermediate, as described above. The resulting hemiketal again exists in equilibrium with a keto alcohol. Our evidence suggests that both routes of lactone metabolism lead to vanillin and vanillic acid, which we show can then be mineralized by strain SG-MS2.IMPORTANCE The oxidative catabolism of (+)-pinoresinol degradation elucidated here is fundamentally different from the reductive cometabolism reported for two previously characterized bacteria. Our findings open up new opportunities to use lignin for the biosynthesis of vanillin, a key flavoring agent in foods, beverages, and pharmaceuticals, as well as various new lactones. Our work also has implications for the study of new pinoresinol metabolites in human health. The enterodiol and enterolactone produced through reductive transformation of pinoresinol by gut microbes have already been associated with decreased risks of cancer and cardiovascular diseases. The metabolites from oxidative metabolism we find here also deserve attention in this respect.


Subject(s)
Calcification, Physiologic/physiology , Furans/metabolism , Lignans/metabolism , Metabolic Networks and Pathways , Pseudomonas/isolation & purification , Pseudomonas/metabolism , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/metabolism , Benzaldehydes/metabolism , Gastrointestinal Microbiome/physiology , Humans , Lignin/metabolism , Minerals/metabolism , Pseudomonas/genetics
5.
Clin Chem Lab Med ; 53(4): 583-92, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25581762

ABSTRACT

BACKGROUND: Whether or not antibiotic stewardship protocols based on procalcitonin levels results in cost savings remains unclear. Herein, our objective was to assess the economic impact of adopting procalcitonin testing among patients with suspected acute respiratory tract infection (ARI) from the perspective of a typical US integrated delivery network (IDN) with a 1,000,000 member catchment area or enrollment. METHODS: To conduct an economic evaluation of procalcitonin testing versus usual care we built a cost-impact model based on patient-level meta-analysis data of randomized trials. The meta-analytic data was adapted to the US setting by applying the meta-analytic results to US lengths of stay, costs, and practice patterns. We estimated the annual ARI visit rate for the one million member cohort, by setting (inpatient, ICU, outpatient) and ARI diagnosis. RESULTS: In the inpatient setting, the costs of procalcitonin-guided compared to usual care for the one million member cohort was $2,083,545, compared to $2,780,322, resulting in net savings of nearly $700,000 to the IDN for 2014. In the ICU and outpatient settings, savings were $73,326 and $5,329,824, respectively, summing up to overall net savings of $6,099,927 for the cohort. RESULTS were robust for all ARI diagnoses. For the whole US insured population, procalcitonin-guided care would result in $1.6 billion in savings annually. CONCLUSIONS: Our results show substantial savings associated with procalcitonin protocols of ARI across common US treatment settings mainly by direct reduction in unnecessary antibiotic utilization. These results are robust to changes in key parameters, and the savings can be achieved without any negative impact on treatment outcomes.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Blood Chemical Analysis/economics , Calcitonin/blood , Delivery of Health Care/economics , Protein Precursors/blood , Respiratory Tract Infections/blood , Respiratory Tract Infections/drug therapy , Acute Disease , Calcitonin Gene-Related Peptide , Cost-Benefit Analysis , Humans , Inpatients , Length of Stay/economics , Meta-Analysis as Topic , Respiratory Tract Infections/economics , United States
6.
Cochrane Database Syst Rev ; (12): CD010598, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26624987

ABSTRACT

BACKGROUND: Zuclopenthixol is an older antipsychotic that has three distinct formulations (zuclopenthixol dihydrochloride, zuclopenthixol acetate or Acuphase and zuclopenthixol decanoate). Although it has been in common use for many years no previous systematic review of its efficacy compared to placebo in schizophrenia has been undertaken. OBJECTIVES: To evaluate the effectiveness of all formulations of zuclopenthixol when compared with a placebo in schizophrenia. SEARCH METHODS: On 6 November 2013 and 20 October 2015, we searched the Cochrane Schizophrenia Group Trials Register, which is based on regular searches of MEDLINE, EMBASE, CINAHL, BIOSIS, AMED, PubMed, PsycINFO, and registries of clinical trials. We also checked the references of all included studies and contacted authors of included studies for relevant studies and data. SELECTION CRITERIA: We included all randomised controlled trials comparing zuclopenthixol of any form with placebo for treatment of schizophrenia or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: We extracted and cross-checked data independently. We identified only a small number of studies so we cross checked all studies. We calculated fixed-effect relative risks (RR) and 95% confidence intervals (CI) for dichotomous data. We analysed by intention-to-treat. Where possible we converted continuous outcomes into dichotomous outcomes. When this was not possible we used mean differences (MD) for continuous variables. We assessed risk of bias for included studies and used GRADE (Grading of Recommendations Assessment, Development and Evaluation) to create a 'Summary of findings' table. MAIN RESULTS: Only two studies, with a total of 65 participants, were eligible for inclusion in the review. Overall the quality of the two studies was low, with small study populations and significant sources of bias, so we were not able to use all the data in our comparisons. . The studies were old from 1968 and 1972, and would be unlikely to pass modern peer review standard. We were only able to find short-term data and only trials randomising zuclopenthixol dihydrochloride. We also hoped to identify data for zuclopenthixol acetate versus placebo and zuclopenthixol decanoate versus placebo comparisons. We were unable to identify any studies that included data on these two fairly widely used drugs.For our primary outcome of interest, clinically significant improvement, we found one study that provided useable data. Global state measured by clinical global impression scale (CGI) improvement showed different ratings when assessed by a psychiatrist or a nurse.The psychiatrist scores failed to achieve statistical significance, however when assessed by nursing staff, the difference favouring zuclopenthixol did reach statistical significance (1 RCT n = 29, RR 2.57 95% CI 1.06 to 6.20, very low quality data). There was also evidence of increased sedation with those treated with zuclopenthixol when compared with placebo (1 RCT n = 29, RR 4.67 95% CI 1.23 to 17.68, very low quality data). 'Leaving the study early' data were equivocal. No useable data were available for outcomes such as relapse, mental state, death, quality of life, service use or economic costs. AUTHORS' CONCLUSIONS: For people with schizophrenia this review shows that zuclopenthixol dihydrochloride may help with the symptoms of schizophrenia. The review provides some trial evidence that, if taking zuclopenthixol dihydrochloride, people may experience some adverse effects and sedation compared with placebo. However this evidence is of very low quality and with some significant sources of bias. There are no data for zuclopenthixol decanoate or zuclopenthixol acetate.For clinicians, the available trial data on the absolute effectiveness of zuclopenthixol dihydrochloride do support its use but the limited nature of the data and significant sources of bias make conclusions hard to draw. Zuclopenthixol in all three forms is a commonly used antipsychotic and it is disappointing that there are so few data regarding its use.


Subject(s)
Clopenthixol/therapeutic use , Schizophrenia/drug therapy , Antipsychotic Agents/adverse effects , Antipsychotic Agents/therapeutic use , Clopenthixol/adverse effects , Clopenthixol/analogs & derivatives , Humans , Randomized Controlled Trials as Topic
7.
J Nematol ; 47(2): 116-25, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26170473

ABSTRACT

Proto-anhydrobiosis of the nematode, Beddingia siricidicola, was achieved by incubation in polyethylene glycol or various concentrations up to 4 M of glycerol. The associated changes in the levels of glycerol, unbound proline, trehalose, lipids, and glycogen were determined by alkylation strategies, followed by gas chromatography or gas chromatography/mass spectrometry. The level of glycerol reached 8.9% of dry weight, proline 2.4% of dry weight, and trehalose 8.0% of dry weight within B. siricidicola that were incubated in 1.5 M glycerol over 6 d, while glycerol reached 17.9% of dry weight after incubation for the same period in 4 M glycerol. Movement was thereby reduced but the nematodes from 1.5 M glycerol revived after a few minutes upon rehydrating and they were able to avoid osmotic damage by rapidly excreting the glycerol, much of it being expelled within the first hour. The potential for storage and transport of this nematode for the biological control of the pine-killing wasp, Sirex noctilio, was greatly improved when nematode suspensions were maintained in 1.5 M glycerol under refrigeration.

8.
PLoS One ; 18(4): e0285099, 2023.
Article in English | MEDLINE | ID: mdl-37115788

ABSTRACT

Divergence between populations in mating behaviour can function as a potent premating isolating mechanism and promote speciation. However, very few cases of inherited intraspecific variation in sexual signalling have been reported in tephritid fruit flies, despite them being a highly speciose family. We tested for such variation in one tephritid, the Queensland fruit fly, Bactrocera tryoni (Qfly). Qfly mating behaviour depends on volatiles secreted from male rectal glands but no role for the volatiles from female rectal glands has yet been reported. We previously detected over 100 volatile compounds in male rectal glands and identified over 30 of them. Similar numbers were recorded in females. However, many compounds showed presence/absence differences between the sexes and many others showed quantitative differences between them. Here we report inherited variation among 24 Qfly lines (23 isofemale lines established from recent field collections and one domesticated line) in the abundance of three esters, two alcohols, two amides, an aldehyde and 18 unidentified volatiles in male rectal glands. We did not find any compounds in female rectal glands that varied significantly among the lines, although this may at least partly reflect lower female sample numbers. Most of the 26 male compounds that differed between lines were more abundant in the domesticated line than any of the recently established isofemale lines, which concurs with other evidence for changes in mating behaviour during domestication of this species. There were also large differences in several of the 26 compounds among the isofemale lines, and some of these differences were associated with the regions from which the lines were collected. While some of the variation in different compounds was correlated across lines, much of it was not, implicating involvement of multiple genes. Our findings parallel reports of geographic variation in other Qfly traits and point to inherited differences in reproductive physiology that could provide a basis for evolution of premating isolation between ecotypes.


Subject(s)
Tephritidae , Animals , Male , Female , Tephritidae/genetics , Salt Gland , Drosophila , Domestication , Genetic Variation
9.
Chem Senses ; 37(1): 55-63, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21835765

ABSTRACT

Within the multitude of chemical signals used by termites, the trail marking by means of pheromones is ubiquitous. Chemistry and biology of the trail-following communication have been described in more than 60 species from all families except for the Neotropical Serritermitidae. The chemical ecology of Serritermitidae is of special interest not only as a missing piece of knowledge on the diversity and evolution of isopteran pheromones but also because it may contribute to the debate on the phylogenetic position of this family, which is still unresolved. Therefore, we aimed in this study to identify the trail-following pheromone of the serritermitid Glossotermes oculatus. Based on a combined approach of analytical chemistry, electrophysiology, and behavioral bioassays, we propose (10Z,13Z)-nonadeca-10,13-dien-2-one to be the trail-following pheromone of G. oculatus, secreted by the sternal gland of pseudergates. Thus, we report on a new termite trail-following pheromone of an unexpected chemical structure, a ketone with 19 carbons, contrasting with unsaturated alcohols containing 12 carbons as trail-following pheromones in other advanced termite families. In addition to this unique trail-following pheromone, we also describe the sternal gland in pseudergates as an organ of unusual shape, size, and structure when compared with other isopteran species. These results underline the peculiarity of the family Serritermitidae and prompt our interest in the chemistry of pheromones in the other genus of the family, Serritermes.


Subject(s)
Fatty Acids, Unsaturated/analysis , Isoptera/chemistry , Pheromones/analysis , Animals , Behavior, Animal/drug effects , Biological Assay , Exocrine Glands/anatomy & histology , Exocrine Glands/chemistry , Exocrine Glands/metabolism , Fatty Acids, Unsaturated/chemical synthesis , Fatty Acids, Unsaturated/chemistry , Isoptera/physiology , Pheromones/chemical synthesis , Pheromones/chemistry , Pheromones/metabolism , Pheromones/pharmacology
10.
PLoS One ; 17(8): e0273210, 2022.
Article in English | MEDLINE | ID: mdl-36001616

ABSTRACT

Rectal gland volatiles are key mediators of sexual interactions in tephritid fruit flies. We used solid-phase microextraction (SPME) plus gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID) to substantially expand rectal gland chemical characterisation of the Queensland fruit fly (Bactrocera tryoni (Diptera: Tephritidae); Qfly). The SPME GC-MS analysis identified 24 of the 30 compounds previously recorded from Qfly rectal glands, plus another 21 compounds that had not previously been reported. A few amides and fatty acid esters dominated the chromatograms of males and females respectively, but we also found other esters, alcohols and aldehydes and a ketone. The GC-FID analyses also revealed over 150 others, as yet unidentified, volatiles, generally in lesser amounts. The GC-FID analyses also showed 49 and 12 compounds were male- and female-specific, respectively, both in single sex (virgin) and mixed sex (mostly mated) groups. Another ten compounds were male-specific among virgins but undetected in mixed sex groups, and 29 were undetected in virgins but male-specific in mixed sex groups. The corresponding figures for females were four and zero, respectively. Most short retention time peaks (including a ketone and an ester) were male-specific, whereas most female-biased peaks (including five fatty acid esters) had long retention times. Our results indicate previously unsuspected diversity of rectal gland volatiles that might have pheromone functions in males, but far fewer in females.


Subject(s)
Tephritidae , Animals , Fatty Acids , Female , Gas Chromatography-Mass Spectrometry , Ketones , Male , Salt Gland , Sex Characteristics
11.
J Econ Entomol ; 104(1): 232-42, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21404863

ABSTRACT

Termites (Isoptera) have often been proposed as decomposers oflignocellulosic waste, such as paper products, while termite biomass could be harvested for food supplements. Groups of Coptotermes formosanus Shiraki and Reticulitermes speratus (Kolbe) were kept for 4 and 8 wk, respectively, in the laboratory and given up to 10 different types of paper as their food source. Paper consumption, survival, caste composition, and lipid content were recorded. Corrugated cardboard was by far the most consumed paper product, although survival on it was not necessarily favorable. In R. speratus, lipid reserves and neotenic numbers were quite high, but no breeding occurred. Cardboard may be the "junk food" equivalent for termites. Within the tested period, termites did not perform well on paper products that form the bulk of waste paper--corrugated cardboard, newsprint, and pamphlets and magazines. On all paper products (except recycled office paper), neotenic reproductives were formed, but larvae were observed only on kraft pulp and tissue paper. That all waste paper products contain lignocellulosic fibers does not automatically make them suitable for decomposition by termites. Each paper product has to be assessed on its own merit to see whether termites can reproduce on this diet, if it were to be a candidate for sustainable "termidegradation" and termite biomass production.


Subject(s)
Isoptera/metabolism , Paper , Recycling , Animals , Feeding Behavior , Lipid Metabolism , Reproduction
12.
Food Sci Nutr ; 6(8): 2337-2343, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30510733

ABSTRACT

BACKGROUND: Globally, population-wide sodium reduction strategies have been adopted and implemented to address the adverse health effects of excess dietary sodium. However, in Canada, minimal coordinated action by governments has occurred, including interventions aimed at food service operations in hospitals and long-term care (LTC) centers. The objective of this study was to investigate actions, attitudes, barriers, and facilitators related to sodium reduction in these institutions. METHODOLOGY: A cross-sectional survey was administered to food service administrators working in hospitals and LTC facilities in Ontario. Responses from key informants from 27 institutions, representing 9,823 patient/resident beds were included. RESULTS: Overall, 63.0% of institutions had an established sodium target (900-4,000 mg/day). The reported sodium level on "regular" menus was 2,845 ± 1,025 mg/day. Sixty-three percent believed it was important to reduce sodium on inpatient/resident menus. Top facilitators reported for sodium reduction included group purchasing organizations identifying lower sodium foods (85.2%), increased availability of pre-packaged lower sodium products (77.8%), government prioritizing and providing support and resources (74.1%), and improved taste of lower sodium foods (74.1%). Only 37.0% believed that patient/resident satisfaction would decrease with sodium reduction. Sodium reduction practices were variable among food service operations. CONCLUSIONS: These data support the need for consistent and coordinated policies to facilitate sodium reduction in hospitals and long-term care settings and for multi-sectorial government, industry, and institutional support to ensure success.

13.
Heart ; 104(12): 1006-1013, 2018 06.
Article in English | MEDLINE | ID: mdl-29269379

ABSTRACT

OBJECTIVE: Chronic heart failure with reduced ejection fraction (HF-REF) represents a major public health issue and is associated with considerable morbidity and mortality. We evaluated the cost-effectiveness of sacubitril/valsartan (formerly LCZ696) compared with an ACE inhibitor (ACEI) (enalapril) in the treatment of HF-REF from the perspective of healthcare providers in the UK, Denmark and Colombia. METHODS: A cost-utility analysis was performed based on data from a multinational, Phase III randomised controlled trial. A decision-analytic model was developed based on a series of regression models, which extrapolated health-related quality of life, hospitalisation rates and survival over a lifetime horizon. The primary outcome was the incremental cost-effectiveness ratio (ICER). RESULTS: In the UK, the cost per quality-adjusted life-year (QALY) gained for sacubitril/valsartan (using cardiovascular mortality) was £17 100 (€20 400) versus enalapril. In Denmark, the ICER for sacubitril/valsartan was Kr 174 000 (€22 600). In Colombia, the ICER was COP$39.5 million (€11 200) per QALY gained. Deterministic sensitivity analysis showed that results were most sensitive to the extrapolation of mortality, duration of treatment effect and time horizon, but were robust to other structural changes, with most scenarios associated with ICERs below the willingness-to-pay threshold for all three country settings. Probabilistic sensitivity analysis suggested the probability that sacubitril/valsartan was cost-effective at conventional willingness-to-pay thresholds was 68%-94% in the UK, 84% in Denmark and 95% in Colombia. CONCLUSIONS: Our analysis suggests that, in all three countries, sacubitril/valsartan is likely to be cost-effective compared with an ACEI (the current standard of care) in patients with HF-REF.


Subject(s)
Aminobutyrates/economics , Aminobutyrates/therapeutic use , Cardiovascular Agents/economics , Cardiovascular Agents/therapeutic use , Drug Costs , Heart Failure/drug therapy , Heart Failure/economics , Stroke Volume/drug effects , Tetrazoles/economics , Tetrazoles/therapeutic use , Ventricular Function, Left/drug effects , Aminobutyrates/adverse effects , Biphenyl Compounds , Cardiovascular Agents/adverse effects , Chronic Disease , Clinical Trials, Phase III as Topic , Colombia , Cost-Benefit Analysis , Denmark , Drug Combinations , Heart Failure/diagnosis , Heart Failure/physiopathology , Humans , Quality-Adjusted Life Years , Randomized Controlled Trials as Topic , Recovery of Function , Tetrazoles/adverse effects , Time Factors , Treatment Outcome , United Kingdom , Valsartan
14.
J Womens Health (Larchmt) ; 25(6): 606-16, 2016 06.
Article in English | MEDLINE | ID: mdl-27023044

ABSTRACT

BACKGROUND: Consensus United States cervical cancer screening guidelines recommend use of combination Pap plus human papillomavirus (HPV) testing for women aged 30 to 65 years. An HPV test was approved by the Food and Drug Administration in 2014 for primary cervical cancer screening in women age 25 years and older. Here, we present the results of clinical-economic comparisons of Pap plus HPV mRNA testing including genotyping for HPV 16/18 (co-testing) versus DNA-based primary HPV testing with HPV 16/18 genotyping and reflex cytology (HPV primary) for cervical cancer screening. METHODS: A health state transition (Markov) model with 1-year cycling was developed using epidemiologic, clinical, and economic data from healthcare databases and published literature. A hypothetical cohort of one million women receiving triennial cervical cancer screening was simulated from ages 30 to 70 years. Screening strategies compared HPV primary to co-testing. Outcomes included total and incremental differences in costs, invasive cervical cancer (ICC) cases, ICC deaths, number of colposcopies, and quality-adjusted life years for cost-effectiveness calculations. Comprehensive sensitivity analyses were performed. RESULTS: In a simulation cohort of one million 30-year-old women modeled up to age 70 years, the model predicted that screening with HPV primary testing instead of co-testing could lead to as many as 2,141 more ICC cases and 2,041 more ICC deaths. In the simulation, co-testing demonstrated a greater number of lifetime quality-adjusted life years (22,334) and yielded $39.0 million in savings compared with HPV primary, thereby conferring greater effectiveness at lower cost. CONCLUSIONS: Model results demonstrate that co-testing has the potential to provide improved clinical and economic outcomes when compared with HPV primary. While actual cost and outcome data are evaluated, these findings are relevant to U.S. healthcare payers and women's health policy advocates seeking cost-effective cervical cancer screening technologies.


Subject(s)
Colposcopy/economics , Cost-Benefit Analysis , Mass Screening/economics , Mass Screening/methods , Papillomavirus Infections/diagnosis , Uterine Cervical Neoplasms/economics , Uterine Cervical Neoplasms/prevention & control , Adult , Aged , Computer Simulation , DNA, Viral/isolation & purification , Early Detection of Cancer , Female , Genotype , Human papillomavirus 16 , Human papillomavirus 18 , Humans , Logistic Models , Markov Chains , Middle Aged , Models, Econometric , Papanicolaou Test , Papillomaviridae/genetics , Papillomaviridae/isolation & purification , Papillomavirus Infections/prevention & control , Quality-Adjusted Life Years , United States , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/virology , Uterine Cervical Dysplasia/diagnosis
15.
Circulation ; 110(3): 259-64, 2004 Jul 20.
Article in English | MEDLINE | ID: mdl-15226211

ABSTRACT

BACKGROUND: Outcomes after percutaneous coronary intervention (PCI) have been documented extensively in clinical trials and single-center series, but few data exist on the clinical and economic outcomes after PCI in an unselected population. METHODS AND RESULTS: We used the Medicare Standard Analytic File to identify all initial PCI procedures performed in 1998 among a random sample of 5% of all Medicare beneficiaries > or =65 years of age. These patients (n=9868) were followed up for 1 year after PCI to identify clinical outcomes, medical resource use, and costs. Between 1 month and 1 year after PCI, 16.9% of patients required > or =1 repeat revascularization procedures. Mean 1-year medical care costs increased 5-fold among patients with repeat revascularization compared with those without (26,186 dollars versus 5344 dollars; P<0.001). After adjustment for baseline differences, the independent cost of repeat revascularization was 19,074 dollars (95% CI, 18,440 to 19,707). Assuming from previous studies that 85% of repeat revascularization procedures over the first year of follow-up are attributable to restenosis, the estimated clinical restenosis rate was 14.4%, and the 1-year economic burden of restenosis to the healthcare system was 2747 dollars per initial PCI procedure. CONCLUSIONS: Among unselected elderly patients undergoing PCI, repeat revascularization occurs in approximately 14% and increases 1-year healthcare costs by >19,000 dollars per occurrence. These findings have important implications for the cost-effectiveness of new treatments that substantially reduce restenosis.


Subject(s)
Coronary Restenosis/economics , Myocardial Revascularization/economics , Aged , Angioplasty, Balloon, Coronary , Coronary Restenosis/epidemiology , Coronary Restenosis/prevention & control , Cost-Benefit Analysis , Female , Humans , Male , Medicare , Reoperation , Stents , Treatment Outcome
16.
J Steroid Biochem Mol Biol ; 96(3-4): 279-86, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16023337

ABSTRACT

There is evidence that certain phytoestrogens can inhibit key steroidogenic enzymes although most studies have been carried out on microsomal or purified enzyme preparations, some using cell lines. This study was designed to test the hypothesis that low doses of phytoestrogens, at concentrations that would be attained through the diet, could inhibit 3beta-hydroxysteroid dehydrogenase (HSD) and/or aromatase in primary cultures of human granulosa-luteal (GL) cells and that this effect was due to a decrease in the expression of these proteins. Based on published evidence, eight compounds were selected for investigation and these included the flavones apigenin and quercetin, the isoflavones genistein, biochanin A and daidzein, the lignans, enterodiol and enterolactone, and the mycotoxin zearalenone. Human GL cells were cultured for 48 h in the presence of these phytoestrogens at concentrations ranging from 0.01 to 100 microM and after addition of fresh media the conversion of pregnenolone to progesterone or androstenedione to oestradiol over a 4h period was measured. Biochanin A was the only phytoestrogen that displayed any dose-dependent inhibition of 3beta-HSD, others showing inhibition at doses >/=10 microM. Apigenin and quercetin only inhibited aromatase/17beta-HSD at high doses as did genistein, biochanin A and daidzein. The lignans had weak inhibitory effects on aromatase/17beta-HSD, whilst zearalenone showed potent inhibition at 0.1 microM. Phytoestrogens did not exert any significant effects on protein expression of 3beta-HSD or aromatase as determined by Western blots. It is concluded that steroidogenic enzymes are inhibited by phytoestrogens in primary cultures of human GL cells but these cells are less sensitive to the effects of phytoestrogens than cell-free systems. This may be due to poor lipid solubility or cellular metabolism. We have also shown for the first time that phytoestrogens do not act by inhibiting the cellular concentration of 3beta-HSD and aromatase even though exposure time would have allowed for changes in gene expression.


Subject(s)
3-Hydroxysteroid Dehydrogenases/metabolism , Aromatase/metabolism , Luteal Cells/drug effects , Phytoestrogens/pharmacology , Dose-Response Relationship, Drug , Female , Humans , Luteal Cells/enzymology , Steroids/metabolism
17.
J Magn Reson ; 162(1): 133-40, 2003 May.
Article in English | MEDLINE | ID: mdl-12762990

ABSTRACT

In capillary electrophoresis separations coupled to NMR signal detection using small solenoidal coils, electrophoretic currents cause substantial distortion in the NMR spectral linewidths and peak heights, distortions which cannot be fully counteracted through shimming. The NMR spectra also have a low signal-to-noise ratio due to the small amounts of material, typically <1nmol, associated with such microseparations. This study proposes a two-step, signal processing method to restore spectral lines from the distorted NMR spectrum. First, a reference signal is acquired to estimate the broadening function, as a combination of several Lorentzian functions, using a gradient descent method. Then multi-resolution wavelet analysis is applied to the distorted spectrum to determine an initial estimate of the frequencies of the spectral lines. Convergence to the final spectrum, a second set of Lorentzians, involves deconvolution with the estimated broadening function using a gradient descent method. Experimental CE-NMR data show that considerable improvements in spectral quality are possible using this approach, although fine splittings can not be resolved if the broadening function is large.


Subject(s)
Magnetic Resonance Spectroscopy/methods , Algorithms , Electrophoresis, Capillary/methods , Signal Processing, Computer-Assisted , Sucrose/chemistry
18.
BMC Cardiovasc Disord ; 4: 23, 2004 Dec 13.
Article in English | MEDLINE | ID: mdl-15596004

ABSTRACT

BACKGROUND: To evaluate current treatment patterns for coronary artery revascularization in Canada and explore the potential impact of drug eluting stents (DES) on these treatment patterns. METHODS: Eleven cardiologists at multiple Canadian academic centers completed a questionnaire on coronary artery revascularization rates and treatment patterns. RESULTS: Participating physicians indicated slightly higher rates of PTCA, CABG, and stent implantation than reported in CCN publications. Participants estimated that 24% of all patients currently receiving bare metal stents (BMS) would receive DES in the first year following DES approval in Canada, although there was a large range of estimates around this value (5% to 65%). By the fifth year following DES approval, it was estimated that 85% of BMS patients would instead receive DES. Among diabetic patients, estimates ranged from 43% in the first year following approval to 91% in the fifth year. For all patients currently receiving CABG, mean use of DES instead was estimated at 12% in the first year to 42% at five years; rates among diabetic patients currently undergoing CABG were 17% in the first year to 49% in the fifth year. CONCLUSIONS: These results suggest a continued increase in revascularization procedures in Canada. Based on the panel's responses, it is likely that a trend away from CABG towards PTCA will continue in Canada, and will be augmented by the availability of DES as a treatment option. The availability of DES as a treatment option in Canada may change the threshold at which revascularization procedures are considered.


Subject(s)
Coronary Artery Disease/therapy , Myocardial Revascularization/statistics & numerical data , Practice Patterns, Physicians' , Stents , Adult , Angioplasty, Balloon, Coronary/statistics & numerical data , Canada , Cardiology , Coronary Artery Bypass/statistics & numerical data , Coronary Artery Disease/economics , Device Approval , Humans , Male , Myocardial Revascularization/economics , Stents/economics , Stents/statistics & numerical data , Surveys and Questionnaires
19.
PLoS One ; 9(1): e85109, 2014.
Article in English | MEDLINE | ID: mdl-24465488

ABSTRACT

Beta frequency oscillations (10-35 Hz) in motor regions of cerebral cortex play an important role in stabilising and suppressing unwanted movements, and become intensified during the pathological akinesia of Parkinson's Disease. We have used a cortical slice preparation of rat brain, combined with concurrent intracellular and field recordings from the primary motor cortex (M1), to explore the cellular basis of the persistent beta frequency (27-30 Hz) oscillations manifest in local field potentials (LFP) in layers II and V of M1 produced by continuous perfusion of kainic acid (100 nM) and carbachol (5 µM). Spontaneous depolarizing GABA-ergic IPSPs in layer V cells, intracellularly dialyzed with KCl and IEM1460 (to block glutamatergic EPSCs), were recorded at -80 mV. IPSPs showed a highly significant (P< 0.01) beta frequency component, which was highly significantly coherent with both the Layer II and V LFP oscillation (which were in antiphase to each other). Both IPSPs and the LFP beta oscillations were abolished by the GABAA antagonist bicuculline. Layer V cells at rest fired spontaneous action potentials at sub-beta frequencies (mean of 7.1+1.2 Hz; n = 27) which were phase-locked to the layer V LFP beta oscillation, preceding the peak of the LFP beta oscillation by some 20 ms. We propose that M1 beta oscillations, in common with other oscillations in other brain regions, can arise from synchronous hyperpolarization of pyramidal cells driven by synaptic inputs from a GABA-ergic interneuronal network (or networks) entrained by recurrent excitation derived from pyramidal cells. This mechanism plays an important role in both the physiology and pathophysiology of control of voluntary movement generation.


Subject(s)
Inhibitory Postsynaptic Potentials/physiology , Motor Cortex/physiology , Neurons/physiology , Action Potentials/physiology , Animals , Electrophysiology , Male , Rats , Rats, Wistar
20.
J Am Soc Hypertens ; 7(1): 46-60, 2013.
Article in English | MEDLINE | ID: mdl-23321404

ABSTRACT

Poor antihypertensive treatment adherence adversely affects blood pressure control. We analyzed US health plan data to assess the impact of fixed- versus loose-dose triple-combination therapy on adherence, clinical, and economic outcomes. Patients initiating triple therapy with an angiotensin receptor blocker, angiotensin-converting enzyme inhibitor, or beta blocker plus amlodipine and hydrochlorothiazide comprised three cohorts. Within-cohort comparisons were made between fixed-dose combinations of two antihypertensives plus a second pill (two pills) or three separate pills. Outcomes included adherence, cardiovascular events, health care resource use, and costs for patients with ≥ 12 months follow-up. A total of 16,290 patients were matched. Patients receiving two pills were more likely to be adherent (P < .001) and less likely to discontinue treatment (P < .001) across all cohorts. Therapy with two versus three pills resulted in significantly lower adjusted risk of cardiovascular events (hazard ratio = 0.76, P = .005) in the beta blocker cohort only. Total adjusted health care costs were significantly lower for two- versus three-pill therapy in the beta blocker cohort only (cost ratio = 0.74 overall, P < .01; 0.71 hypertension-attributable, P < .01). In patients with hypertension requiring triple therapy, fixed-dose combinations that lower pill burden may improve adherence (seen across all cohorts) and clinical outcomes (seen in the beta blocker cohort) without increasing health care costs.


Subject(s)
Antihypertensive Agents/economics , Antihypertensive Agents/therapeutic use , Hypertension/drug therapy , Hypertension/economics , Medication Adherence/statistics & numerical data , Adrenergic beta-Antagonists/economics , Adrenergic beta-Antagonists/therapeutic use , Adult , Aged , Angiotensin II Type 1 Receptor Blockers/economics , Angiotensin II Type 1 Receptor Blockers/therapeutic use , Angiotensin Receptor Antagonists/economics , Angiotensin Receptor Antagonists/therapeutic use , Calcium Channel Blockers/economics , Calcium Channel Blockers/therapeutic use , Cost-Benefit Analysis , Diuretics/economics , Diuretics/therapeutic use , Drug Therapy, Combination/economics , Female , Humans , Hypertension/epidemiology , Male , Middle Aged , Prevalence , Retrospective Studies , Treatment Outcome , United States/epidemiology
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