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1.
PLoS One ; 18(4): e0285099, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37115788

RESUMEN

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.


Asunto(s)
Tephritidae , Animales , Masculino , Femenino , Tephritidae/genética , Glándula de Sal , Drosophila , Domesticación , Variación Genética
2.
PLoS One ; 17(8): e0273210, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36001616

RESUMEN

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.


Asunto(s)
Tephritidae , Animales , Ácidos Grasos , Femenino , Cromatografía de Gases y Espectrometría de Masas , Cetonas , Masculino , Glándula de Sal , Caracteres Sexuales
3.
J Chem Ecol ; 46(5-6): 475-482, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32529331

RESUMEN

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.


Asunto(s)
Isópteros/fisiología , Feromonas/metabolismo , Animales
4.
Appl Environ Microbiol ; 86(10)2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32198167

RESUMEN

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.


Asunto(s)
Proteínas Bacterianas/genética , Flavoproteínas/genética , Furanos/metabolismo , Genes Bacterianos/genética , Lignanos/metabolismo , Pseudomonas/genética , Proteínas Bacterianas/metabolismo , Flavoproteínas/metabolismo , Redes y Vías Metabólicas , Familia de Multigenes , Oxidación-Reducción , Pseudomonas/metabolismo
5.
Appl Environ Microbiol ; 84(4)2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29222099

RESUMEN

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.


Asunto(s)
Calcificación Fisiológica/fisiología , Furanos/metabolismo , Lignanos/metabolismo , Redes y Vías Metabólicas , Pseudomonas/aislamiento & purificación , Pseudomonas/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Benzaldehídos/metabolismo , Microbioma Gastrointestinal/fisiología , Humanos , Lignina/metabolismo , Minerales/metabolismo , Pseudomonas/genética
6.
J Womens Health (Larchmt) ; 25(6): 606-16, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27023044

RESUMEN

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.


Asunto(s)
Colposcopía/economía , Análisis Costo-Beneficio , Tamizaje Masivo/economía , Tamizaje Masivo/métodos , Infecciones por Papillomavirus/diagnóstico , Neoplasias del Cuello Uterino/economía , Neoplasias del Cuello Uterino/prevención & control , Adulto , Anciano , Simulación por Computador , ADN Viral/aislamiento & purificación , Detección Precoz del Cáncer , Femenino , Genotipo , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Humanos , Modelos Logísticos , Cadenas de Markov , Persona de Mediana Edad , Modelos Econométricos , Prueba de Papanicolaou , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/prevención & control , Años de Vida Ajustados por Calidad de Vida , Estados Unidos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/diagnóstico
7.
J Nematol ; 47(2): 116-25, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26170473

RESUMEN

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.
Clin Chem Lab Med ; 53(4): 583-92, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25581762

RESUMEN

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.


Asunto(s)
Antibacterianos/uso terapéutico , Análisis Químico de la Sangre/economía , Calcitonina/sangre , Atención a la Salud/economía , Precursores de Proteínas/sangre , Infecciones del Sistema Respiratorio/sangre , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Enfermedad Aguda , Péptido Relacionado con Gen de Calcitonina , Análisis Costo-Beneficio , Humanos , Pacientes Internos , Tiempo de Internación/economía , Metaanálisis como Asunto , Infecciones del Sistema Respiratorio/economía , Estados Unidos
9.
Chem Senses ; 37(1): 55-63, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21835765

RESUMEN

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.


Asunto(s)
Ácidos Grasos Insaturados/análisis , Isópteros/química , Feromonas/análisis , Animales , Conducta Animal/efectos de los fármacos , Bioensayo , Glándulas Exocrinas/anatomía & histología , Glándulas Exocrinas/química , Glándulas Exocrinas/metabolismo , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Isópteros/fisiología , Feromonas/síntesis química , Feromonas/química , Feromonas/metabolismo , Feromonas/farmacología
10.
J Insect Physiol ; 57(12): 1585-91, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21839084

RESUMEN

The trail-following pheromone and sex pheromones were investigated in the Indomalayan termite Hodotermopsis sjoestedti belonging to the new family Archotermopsidae. Gas chromatography coupled to mass spectrometry (GC-MS) after solid phase microextraction (SPME) of the sternal gland secretion of pseudergates and trail-following bioassays demonstrated that the trail-following pheromone of H. sjoestedti was syn-4,6-dimethylundecan-1-ol, a new chemical structure for termite pheromones. GC-MS after SPME of the sternal gland secretion of alates also allowed the identification of sex-specific compounds. In female alates, the major sex-specific compound was identified as (5E)-2,6,10-trimethylundeca-5,9-dienal, a compound previously identified as the female sex pheromone of the termite Zootermopsis nevadensis. In male alates, the major sex-specific compound was identified as syn-4,6-dimethylundecanal, a homolog of syn-4,6-dimethyldodecanal, which has previously been confirmed as the male sex pheromone of Z. nevadensis. The presence of sex-specific compounds in alates of H. sjoestedti strongly suggests for this termite the presence of sex-specific pairing pheromones which were only known until now in Z. nevadensis. Our results showed therefore a close chemical relationship between the pheromones of the taxa Hodotermopsis and Zootermopsis and, in contrast, a clear difference with the taxa Stolotermes and Porotermes, which is in total agreement with the recent creation of the families Archotermopsidae and Stolotermitidae as a substitute for the former family Termopsidae.


Asunto(s)
Comunicación Animal , Isópteros/química , Atractivos Sexuales/aislamiento & purificación , Conducta Sexual Animal , Aldehídos/aislamiento & purificación , Animales , Alcoholes Grasos/aislamiento & purificación , Femenino , Masculino , Atractivos Sexuales/química
11.
J Econ Entomol ; 104(1): 232-42, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21404863

RESUMEN

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.


Asunto(s)
Isópteros/metabolismo , Papel , Reciclaje , Animales , Conducta Alimentaria , Metabolismo de los Lípidos , Reproducción
12.
J Insect Physiol ; 56(1): 1-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19682453

RESUMEN

In contrast to the majority of the Order, the dampwood termites of the family Termopsidae found in colder regions can experience frost and snow, either in cool temperate areas at high latitudes (45 degrees ), or alpine areas at high elevations (>1000m). This suggests that dampwood termites are adapted to cold climates. We investigated this hypothesis in two dampwood termites, Porotermes adamsoni Froggatt and Stolotermes victoriensis Hill. We measured nest temperatures and atmospheric temperatures of their alpine habitat during winter, and measured survival and recovery at subzero temperatures. We also determined the minimum temperature at which these species remain active and the LT50 values. We used a novel gas chromatographic strategy to examine eight metabolites from individuals of both species collected in winter and summer to identify possible cryoprotectants. Both P. adamsoni and S. victoriensis had significantly higher levels of trehalose, a known cryoprotectant, in winter than in summer; in addition S. victoriensis also had higher levels of unsaturated fatty acid ligands in winter than in summer, consistent with patterns observed for cold adaptation in other organisms. These results are the first to reveal that dampwood termites are adapted to cold climates and use trehalose and unsaturated lipids as cryoprotectants.


Asunto(s)
Conducta Animal , Crioprotectores/metabolismo , Congelación , Isópteros/fisiología , Animales , Crioprotectores/aislamiento & purificación , Grasas Insaturadas/metabolismo , Isópteros/química , Trehalosa/metabolismo
13.
World J Gastroenterol ; 15(45): 5685-92, 2009 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-19960565

RESUMEN

AIM: To model clinical and economic benefits of capsule endoscopy (CE) compared to ileo-colonoscopy and small bowel follow-through (SBFT) for evaluation of suspected Crohn's disease (CD). METHODS: Using decision analytic modeling, total and yearly costs of diagnostic work-up for suspected CD were calculated, including procedure-related adverse events, hospitalizations, office visits, and medications. The model compared CE to SBFT following ileo-colonoscopy and secondarily compared CE to SBFT for initial evaluation. RESULTS: Aggregate charges for newly diagnosed, medically managed patients are approximately $8295. Patients requiring aggressive medical management costs are $29,508; requiring hospitalization, $49,074. At sensitivity > 98.7% and specificity of > 86.4%, CE is less costly than SBFT. CONCLUSION: Costs of CE for diagnostic evaluation of suspected CD is comparable to SBFT and may be used immediately following ileo-colonoscopy.


Asunto(s)
Endoscopía Capsular/economía , Enfermedad de Crohn/diagnóstico , Modelos Económicos , Endoscopía Capsular/métodos , Ensayos Clínicos como Asunto , Enfermedad de Crohn/economía , Enfermedad de Crohn/patología , Enfermedad de Crohn/terapia , Bases de Datos Factuales , Toma de Decisiones , Costos de la Atención en Salud , Humanos , Reembolso de Seguro de Salud , Intestino Delgado/patología , Método de Montecarlo , Sensibilidad y Especificidad
14.
Gastrointest Endosc ; 67(3): 489-96, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18179793

RESUMEN

BACKGROUND: Patterns of GI endoscopy are influenced by the underlying epidemiology of GI disease, as well as by policy and practice guidelines. OBJECTIVE: To compare practice patterns of GI endoscopy between two large national databases of the United States. DESIGN: Descriptive database analysis. SETTING: A 5% sample of the entire U.S. Medicare population (Centers for Medicare and Medicaid Services, CMS data files) and endoscopic data repository of U.S. gastroenterology practices (Clinical Outcomes Research Initiative, CORI database) from 1999 to 2003. PATIENTS: The study population included 1,121,215 Medicare and 635,573 CORI patients undergoing various types of GI endoscopy. INTERVENTIONS: EGD, colonoscopy, and flexible sigmoidoscopy. MAIN OUTCOME MEASUREMENTS: Patient demographics, endoscopic diagnoses, time trends of diagnoses. RESULTS: A colonoscopy was the most common endoscopic procedure performed (CMS 53%, CORI 58%), followed by an EGD (37%, 32%), and a flexible sigmoidoscopy (10%, 10%). In the CMS data, women accounted for 59% of the EGDs, 57% of the colonoscopies, and 56% of the flexible sigmoidoscopies, and in the CORI data, the corresponding numbers were 57%, 55%, and 54%, respectively. Compared with their distribution in the U.S. census population, nonwhite patients in both databases underwent relatively more EGDs and fewer colonoscopies. The most common upper-GI diagnosis was GERD, followed by GI bleeding, gastric ulcer, and duodenal ulcer. The most common lower-GI diagnosis was colorectal polyp. Over the period of 1999 to 2003, the rates of colorectal cancer diagnosed with colonoscopy declined. LIMITATIONS: Only a limited amount of information about individual patients was retrievable from the electronic databases. CONCLUSIONS: A colonoscopy is now the most common endoscopic procedure in the United States. Women undergo both upper and lower endoscopic procedures more often than men. Nonwhite patients are underrepresented in the use of colonoscopy relative to the prevalence of nonwhite persons in the U.S. population. Increased use of a colonoscopy for colon screening and surveillance has been associated with a decreased rate of cancer diagnosis.


Asunto(s)
Endoscopía Gastrointestinal/estadística & datos numéricos , Enfermedades Gastrointestinales/epidemiología , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Enfermedades Gastrointestinales/diagnóstico , Humanos , Masculino , Medicaid/estadística & datos numéricos , Medicare/estadística & datos numéricos , Persona de Mediana Edad , Aceptación de la Atención de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Estados Unidos/epidemiología
15.
J Chem Ecol ; 33(10): 1960-77, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17885791

RESUMEN

In the framework of an evolutionary study, trail pheromones have been studied in the most basal extant termite, Mastotermes darwiniensis (Mastotermitidae), and two other basal termites, the Termopsidae Porotermes adamsoni (Porotermitinae) and Stolotermes victoriensis (Stolotermitinae). Although workers of M. darwiniensis do not walk in single file while exploring a new environment under experimental conditions and are unable to follow artificial trails in 'open field' experiments, they do secrete a trail-following pheromone from their sternal glands. This unique behavior might reflect a primitive function of communication of the sternal gland. The major component of the pheromone appears to be the same in the three basal species: the norsesquiterpene alcohol (E)-2,6,10-trimethyl-5,9-undecadien-1-ol. This represents a new chemical category of trail-following pheromones for termites. The quantity of pheromone was estimated as 20 pg/individual in M. darwiniensis, 700 pg/individual in P. adamsoni, and 4 pg/individual in S. victoriensis. The activity threshold was 1 ng/cm in M. darwiniensis and 10 pg/cm in P. adamsoni. In M. darwiniensis, the trail pheromone was secreted by sternal gland 4 and to a lesser degree by sternal gland 3, sternal gland 5 being almost inactive. This study highlighted phylogenetic relationships between the Mastotermitidae and two subfamilies of the Termopsidae, the Porotermitinae and the Stolotermitinae. Furthermore, it indicated a heterogeneity within the Termopsidae, with Porotermitinae and Stolotermitinae on one hand, and Termopsinae on the other. Finally, Mastotermitidae and Termopsidae, with C14 trail pheromones, are clearly separated from the Kalotermitidae, Rhinotermitidae, and Termitidae that secrete C12 or C20 trail pheromones.


Asunto(s)
Conducta Animal/efectos de los fármacos , Isópteros/fisiología , Actividad Motora/efectos de los fármacos , Feromonas/farmacología , Animales , Conducta Animal/fisiología , Relación Dosis-Respuesta a Droga , Ácidos Grasos/química , Ácidos Grasos/farmacología , Actividad Motora/fisiología , Feromonas/química
16.
J Am Coll Cardiol ; 48(2): 253-61, 2006 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-16843171

RESUMEN

OBJECTIVES: This study sought to compare aggregate medical care costs for patients undergoing percutaneous coronary intervention with paclitaxel-eluting stents (PES) and bare-metal stents (BMS) and to formally evaluate the incremental cost effectiveness of PES for patients undergoing single-vessel percutaneous coronary intervention. BACKGROUND: Although the cost effectiveness of SES has been studied in both clinical trials and decision-analytic models, few data exist on the cost effectiveness of alternative drug-eluting stent (DES) designs. In addition, no clinical trials have specifically examined the cost effectiveness of DES among patients managed without mandatory angiographic follow-up. METHODS: We performed a prospective economic evaluation among 1,314 patients undergoing percutaneous coronary revascularization randomized to either PES (N = 662) or BMS (N = 652) in the TAXUS-IV trial. Clinical outcomes, resource use, and costs (from a societal perspective) were assessed prospectively for all patients over a 1-year follow-up period. Cost effectiveness was defined as the incremental cost per target vessel revascularization (TVR) event avoided and was analyzed separately among cohorts assigned to mandatory angiographic follow-up (n = 732) or clinical follow-up alone (n = 582). RESULTS: The PES reduced TVR by 12.2 events per 100 patients treated, resulting in a 1-year cost difference of 572 dollars per patient with incremental cost-effectiveness ratios of 4,678 dollars per TVR avoided and 47,798 dollars/quality-adjusted life year (QALY) gained. Among patients assigned to clinical follow-up alone, the net 1-year cost difference was 97 dollars per patient with cost-effectiveness ratios of 760 dollars per TVR event avoided and $5,105/QALY gained. CONCLUSIONS: In the TAXUS-IV trial, treatment with PES led to substantial reductions in the need for repeat revascularization while increasing 1-year costs only modestly. The cost-effectiveness ratio for PES in the study population compares reasonably with that for other treatments that reduce coronary restenosis, including alternative drug-eluting stent platforms.


Asunto(s)
Angioplastia Coronaria con Balón/economía , Fármacos Cardiovasculares/administración & dosificación , Enfermedad Coronaria/terapia , Costos de la Atención en Salud/estadística & datos numéricos , Paclitaxel/administración & dosificación , Stents/economía , Anciano , Enfermedad Coronaria/economía , Análisis Costo-Beneficio , Método Doble Ciego , Femenino , Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Retratamiento/economía , Resultado del Tratamiento , Estados Unidos
17.
Circulation ; 110(3): 259-64, 2004 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-15226211

RESUMEN

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.


Asunto(s)
Reestenosis Coronaria/economía , Revascularización Miocárdica/economía , Anciano , Angioplastia Coronaria con Balón , Reestenosis Coronaria/epidemiología , Reestenosis Coronaria/prevención & control , Análisis Costo-Beneficio , Femenino , Humanos , Masculino , Medicare , Reoperación , Stents , Resultado del Tratamiento
18.
Naturwissenschaften ; 91(1): 34-9, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14740102

RESUMEN

The diunsaturated C12 alcohol (Z,Z)-dodeca-3,6-dien-1-ol (dodecadienol) has been characterized by GC-MS and FTIR as a novel releaser pheromone in termites. This alcohol identified in Ancistrotermes pakistanicus (Termitidae, Macrotermitinae) possesses a double pheromonal function which again illustrates the chemical parsimony of termites compared with other social insects. In workers, dodecadienol elicits trail-following at a very low concentration (activity threshold at 0.1 pg/cm of trail); in male alates it induces trail-following at a low concentration (1-10 pg/cm) and sexual attraction at a higher concentration (about 1 ng). Traces of the monounsaturated C12 alcohol (Z)-dodec-3-en-1-ol (dodecenol), known as a trail pheromone of several Macrotermitinae, were also found in the sternal gland extracts of A. pakistanicus, although only dodecadienol was present at the surface of the sternal gland. Workers of A. pakistanicus are not sensitive to dodecenol, but they are as sensitive to dodecatrienol as to dodecadienol. However, in the study area (Vietnam), A. pakistanicus is living in sympatry only with those Macrotermitinae using dodecenol as a trail pheromone, the foraging populations therefore being well isolated through their respective trail pheromones. The presence of three types of unsaturated C12 alcohols as releaser pheromones in the only Macrotermitinae subfamily is discussed, and a possible biosynthetic pathway from linoleic acid is proposed for dodecadienol.


Asunto(s)
Alcadienos/química , Dodecanol/análogos & derivados , Dodecanol/química , Isópteros/fisiología , Feromonas/química , Atractivos Sexuales/análisis , Alcadienos/análisis , Alcadienos/síntesis química , Animales , Dodecanol/análisis , Dodecanol/síntesis química , Espectrometría de Masas , Feromonas/análisis , Feromonas/síntesis química , Atractivos Sexuales/química , Conducta Social
19.
J Chem Ecol ; 28(1): 1-14, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11868667

RESUMEN

The organization of termite societies depends predominantly on intraspecific chemical signals (pheromones) produced by exocrine glands, which induce and modulate individual behavioral responses. Here, the saliva-producing labial glands of termites were investigated with respect to their pheromonal role in communal food exploitation of termite colonies. From these glands, we identified for the first time hydroquinone (1,4-dihydroxybenzene) as a phagostimulating pheromone in the Australian termite species Mastotermes darwiniensis. Hydroquinone is released from the labial glands of termite workers and applied onto the food. It stimulates nestmates to feed at the spot of application and is, thus, employed to mark feeding sites. No synergistic effect with other identified labial gland compounds, such as glucose, inositol, and arbutin, was evident. Significantly, we show that termite species from all over the world, irrespective of taxonomic position and biological traits, produce and employ hydroquinone as phagostimulating signal. The use of the same chemical signal throughout an order is a unique phenomenon, not reported before in animals. Its possible biosynthetic pathway, ecological significance, and evolution are discussed.


Asunto(s)
Conducta Alimentaria/fisiología , Hidroquinonas/metabolismo , Isópteros/fisiología , Feromonas/fisiología , Animales
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